2895 files changed, 127920 insertions, 71469 deletions

diff --git a/.codeclimate.yml b/.codeclimate.yml
index 877c67873d..d59a0780d1 100644
--- a/.codeclimate.yml
+++ b/.codeclimate.yml
@@ -1,26 +1,35 @@
+checks:
+  argument-count:
+    enabled: false
+  complex-logic:
+    enabled: false
+  file-lines:
+    enabled: false
+  method-complexity:
+    enabled: false
+  method-count:
+    enabled: false
+  method-lines:
+    enabled: false
+  nested-control-flow:
+    enabled: false
+  return-statements:
+    enabled: false
+  similar-code:
+    enabled: false
+  identical-code:
+    enabled: false
+
 engines:
   rubocop:
     enabled: true
+    channel: rubocop-0-51
 
 ratings:
   paths:
   - "**.rb"
 
 exclude_paths:
-  - actioncable/lib/rails/generators/
-  - actioncable/test/
-  - actionmailer/lib/rails/generators/
-  - actionmailer/test/
-  - actionpack/test/
-  - actionview/test/
-  - activejob/lib/rails/generators/
-  - activejob/test/
-  - activemodel/test/
-  - activerecord/lib/rails/generators/
-  - activerecord/test/
-  - activesupport/test/
-  - railties/lib/rails/generators/
-  - railties/test/
   - ci/
   - guides/
   - tasks/
diff --git a/.github/pull_request_template.md b/.github/pull_request_template.md
index 48f7b0e214..214d63740c 100644
--- a/.github/pull_request_template.md
+++ b/.github/pull_request_template.md
@@ -11,6 +11,9 @@ If there's anything else that's important and relevant to your pull
 request, mention that information here. This could include
 benchmarks, or other information.
 
+If you are updating any of the CHANGELOG files or are asked to update the
+CHANGELOG files by reviewers, please add the CHANGELOG entry at the top of the file.
+
 Finally, if your pull request affects documentation or any non-code
 changes, guidelines for those changes are [available
 here](http://guides.rubyonrails.org/contributing_to_ruby_on_rails.html#contributing-to-the-rails-documentation)
diff --git a/.github/stale.yml b/.github/stale.yml
new file mode 100644
index 0000000000..71704b3cd7
--- /dev/null
+++ b/.github/stale.yml
@@ -0,0 +1,28 @@
+# Number of days of inactivity before an issue becomes stale
+daysUntilStale: 90
+# Number of days of inactivity before a stale issue is closed
+daysUntilClose: 7
+# Issues with these labels will never be considered stale
+exemptLabels:
+  - pinned
+  - security
+  - With reproduction steps
+  - attached PR
+  - regression
+  - release blocker
+# Label to use when marking an issue as stale
+staleLabel: stale
+# Comment to post when marking an issue as stale. Set to `false` to disable
+markComment: >
+  This issue has been automatically marked as stale because it has not been commented on for at least three months.
+
+  The resources of the Rails team are limited, and so we are asking for your help.
+
+  If you can still reproduce this error on the `5-1-stable` branch or on `master`,
+  please reply with all of the information you have about it in order to keep the issue open.
+
+  Thank you for all your contributions.
+# Comment to post when closing a stale issue. Set to `false` to disable
+closeComment: false
+# Limit to only `issues` or `pulls`
+only: issues
diff --git a/.gitignore b/.gitignore
index 9268977c2f..da3b42cfbb 100644
--- a/.gitignore
+++ b/.gitignore
@@ -3,6 +3,7 @@
 
 .Gemfile
 .ruby-version
+.byebug_history
 debug.log
 pkg
 /.bundle
@@ -13,9 +14,12 @@ pkg
 /activerecord/sqlnet.log
 /activemodel/test/fixtures/fixture_database.sqlite3
 /activesupport/test/fixtures/isolation_test
+/activestorage/test/service/configurations.yml
 /railties/test/500.html
 /railties/test/fixtures/tmp
 /railties/test/initializer/root/log
 /railties/doc
 /railties/tmp
 /guides/output
+node_modules/
+/actionview/log
diff --git a/.rubocop.yml b/.rubocop.yml
index dd8db6af3a..a04de4b497 100644
--- a/.rubocop.yml
+++ b/.rubocop.yml
@@ -1,27 +1,154 @@
 AllCops:
-  TargetRubyVersion: 2.3
+  TargetRubyVersion: 2.2
+  # RuboCop has a bunch of cops enabled by default. This setting tells RuboCop
+  # to ignore them, so only the ones explicitly set in this file are enabled.
   DisabledByDefault: true
+  Exclude:
+    - '**/templates/**/*'
+    - '**/vendor/**/*'
+    - 'actionpack/lib/action_dispatch/journey/parser.rb'
 
-# Two spaces, no tabs (for indentation).
-Style/IndentationWidth:
-  enabled: true
+# Prefer &&/|| over and/or.
+Style/AndOr:
+  Enabled: true
 
-# No trailing whitespace.
-Style/TrailingWhitespace:
-  enabled: true
+# Do not use braces for hash literals when they are the last argument of a
+# method call.
+Style/BracesAroundHashParameters:
+  Enabled: true
+  EnforcedStyle: context_dependent
 
-# Blank lines should not have any spaces.
-Style/TrailingBlankLines:
-  enabled: true
+# Align `when` with `case`.
+Layout/CaseIndentation:
+  Enabled: true
+
+# Align comments with method definitions.
+Layout/CommentIndentation:
+  Enabled: true
+
+Layout/EmptyLineAfterMagicComment:
+  Enabled: true
+
+# In a regular class definition, no empty lines around the body.
+Layout/EmptyLinesAroundClassBody:
+  Enabled: true
+
+# In a regular method definition, no empty lines around the body.
+Layout/EmptyLinesAroundMethodBody:
+  Enabled: true
+
+# In a regular module definition, no empty lines around the body.
+Layout/EmptyLinesAroundModuleBody:
+  Enabled: true
+
+Layout/FirstParameterIndentation:
+  Enabled: true
 
 # Use Ruby >= 1.9 syntax for hashes. Prefer { a: :b } over { :a => :b }.
 Style/HashSyntax:
-  enabled: true
+  Enabled: true
 
-# Prefer &&/|| over and/or.
-Style/AndOr:
-  enabled: true
+# Method definitions after `private` or `protected` isolated calls need one
+# extra level of indentation.
+Layout/IndentationConsistency:
+  Enabled: true
+  EnforcedStyle: rails
+
+# Two spaces, no tabs (for indentation).
+Layout/IndentationWidth:
+  Enabled: true
+
+Layout/LeadingCommentSpace:
+  Enabled: true
+
+Layout/SpaceAfterColon:
+  Enabled: true
+
+Layout/SpaceAfterComma:
+  Enabled: true
+
+Layout/SpaceAroundEqualsInParameterDefault:
+  Enabled: true
+
+Layout/SpaceAroundKeyword:
+  Enabled: true
+
+Layout/SpaceAroundOperators:
+  Enabled: true
+
+Layout/SpaceBeforeComma:
+    Enabled: true
+
+Layout/SpaceBeforeFirstArg:
+    Enabled: true
+
+Style/DefWithParentheses:
+  Enabled: true
+
+# Defining a method with parameters needs parentheses.
+Style/MethodDefParentheses:
+  Enabled: true
+
+Style/FrozenStringLiteralComment:
+  Enabled: true
+  EnforcedStyle: always
+  Exclude:
+    - 'actionview/test/**/*.builder'
+    - 'actionview/test/**/*.ruby'
+    - 'actionpack/test/**/*.builder'
+    - 'actionpack/test/**/*.ruby'
+    - 'activestorage/db/migrate/**/*.rb'
+
+# Use `foo {}` not `foo{}`.
+Layout/SpaceBeforeBlockBraces:
+  Enabled: true
+
+# Use `foo { bar }` not `foo {bar}`.
+Layout/SpaceInsideBlockBraces:
+  Enabled: true
+
+# Use `{ a: 1 }` not `{a:1}`.
+Layout/SpaceInsideHashLiteralBraces:
+  Enabled: true
+
+Layout/SpaceInsideParens:
+  Enabled: true
+
+# Check quotes usage according to lint rule below.
+Style/StringLiterals:
+  Enabled: true
+  EnforcedStyle: double_quotes
+
+# Detect hard tabs, no hard tabs.
+Layout/Tab:
+  Enabled: true
+
+# Blank lines should not have any spaces.
+Layout/TrailingBlankLines:
+  Enabled: true
+
+# No trailing whitespace.
+Layout/TrailingWhitespace:
+  Enabled: true
+
+# Use quotes for string literals when they are enough.
+Style/UnneededPercentQ:
+  Enabled: true
+
+# Align `end` with the matching keyword or starting expression except for
+# assignments, where it should be aligned with the LHS.
+Lint/EndAlignment:
+  Enabled: true
+  EnforcedStyleAlignWith: variable
 
 # Use my_method(my_arg) not my_method( my_arg ) or my_method my_arg.
 Lint/RequireParentheses:
-  enabled: true
+  Enabled: true
+
+Style/RedundantReturn:
+  Enabled: true
+  AllowMultipleReturnValues: true
+
+Style/Semicolon:
+  Enabled: true
+  AllowAsExpressionSeparator: true
diff --git a/.travis.yml b/.travis.yml
index 461bd172c1..1f18478919 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -6,28 +6,38 @@ cache:
   directories:
     - /tmp/cache/unicode_conformance
     - /tmp/beanstalkd-1.10
+    - node_modules
+    - $HOME/.nvm
 
 services:
   - memcached
-  - redis
-  - rabbitmq
+  - redis-server
 
 addons:
-  postgresql: "9.4"
+  postgresql: "9.6"
+  chrome: stable
+  apt:
+    sources:
+      - sourceline: "ppa:mc3man/trusty-media"
+      - sourceline: "ppa:ubuntuhandbook1/apps"
+    packages:
+      - ffmpeg
+      - mupdf
+      - mupdf-tools
 
 bundler_args: --without test --jobs 3 --retry 3
-#FIXME: Remove bundler uninstall on Travis when https://github.com/bundler/bundler/issues/4493 is fixed.
 before_install:
-  - rvm @global do gem uninstall bundler --all --ignore-dependencies --executables
-  - rvm @global do gem install bundler -v '1.11.2'
-  - bundle --version
   - "rm ${BUNDLE_GEMFILE}.lock"
+  - "travis_retry gem update --system"
+  - "travis_retry gem install bundler"
   - "[ -f /tmp/beanstalkd-1.10/Makefile ] || (curl -L https://github.com/kr/beanstalkd/archive/v1.10.tar.gz | tar xz -C /tmp)"
   - "pushd /tmp/beanstalkd-1.10 && make && (./beanstalkd &); popd"
+  - "[[ -z $encrypted_8a915ebdd931_key && -z $encrypted_8a915ebdd931_iv ]] || openssl aes-256-cbc -K $encrypted_8a915ebdd931_key -iv $encrypted_8a915ebdd931_iv -in activestorage/test/service/configurations.yml.enc -out activestorage/test/service/configurations.yml -d"
+  - "[[ $GEM != 'av:ujs' ]] || nvm install node"
+  - "[[ $GEM != 'av:ujs' ]] || node --version"
+  - "[[ $GEM != 'av:ujs' ]] || (cd actionview && npm install)"
 
 before_script:
-  - bundle update
-
   # Set Sauce Labs username and access key. Obfuscated, purposefully not encrypted.
   # Decodes to e.g. `export VARIABLE=VALUE`
   - $(base64 --decode <<< "ZXhwb3J0IFNBVUNFX0FDQ0VTU19LRVk9YTAzNTM0M2YtZTkyMi00MGIzLWFhM2MtMDZiM2VhNjM1YzQ4")
@@ -36,44 +46,85 @@ before_script:
 script: 'ci/travis.rb'
 
 env:
+  global:
+    - "JRUBY_OPTS='--dev -J-Xmx1024M'"
   matrix:
     - "GEM=railties"
-    - "GEM=ap"
-    - "GEM=ac"
-    - "GEM=ac FAYE=1"
-    - "GEM=ac:integration"
-    - "GEM=ac:integration FAYE=1"
-    - "GEM=am,amo,as,av,aj"
+    - "GEM=ap,ac"
+    - "GEM=am,amo,as,av,aj,ast"
     - "GEM=as PRESERVE_TIMEZONES=1"
     - "GEM=ar:mysql2"
     - "GEM=ar:sqlite3"
     - "GEM=ar:postgresql"
-    - "GEM=aj:integration"
     - "GEM=guides"
+    - "GEM=ac:integration"
 
 rvm:
-  - 2.2.5
-  - 2.3.1
+  - 2.2.8
+  - 2.3.5
+  - 2.4.2
+  - 2.5.0
   - ruby-head
 
 matrix:
   include:
-    # Latest compiled version in http://rubies.travis-ci.org
-    - rvm: 2.3.1
+    - rvm: 2.5.0
+      env: "GEM=av:ujs"
+    - rvm: 2.2.8
+      env: "GEM=aj:integration"
+      services:
+        - memcached
+        - redis-server
+        - rabbitmq
+    - rvm: 2.3.5
+      env: "GEM=aj:integration"
+      services:
+        - memcached
+        - redis-server
+        - rabbitmq
+    - rvm: 2.4.2
+      env: "GEM=aj:integration"
+      services:
+        - memcached
+        - redis-server
+        - rabbitmq
+    - rvm: 2.5.0
+      env: "GEM=aj:integration"
+      services:
+        - memcached
+        - redis-server
+        - rabbitmq
+    - rvm: ruby-head
+      env: "GEM=aj:integration"
+      services:
+        - memcached
+        - redis-server
+        - rabbitmq
+    - rvm: 2.3.5
+      env:
+        - "GEM=ar:mysql2 MYSQL=mariadb"
+      addons:
+        mariadb: 10.2
+    - rvm: 2.3.5
+      env:
+        - "GEM=ar:sqlite3_mem"
+    - rvm: 2.3.5
       env:
-        - "GEM=ar:mysql2"
+        - "GEM=ar:postgresql POSTGRES=9.2"
       addons:
-        mariadb: 10.0
-    - rvm: jruby-9.0.5.0
+        postgresql: "9.2"
+    - rvm: jruby-9.1.15.0
       jdk: oraclejdk8
       env:
-        - "JRUBY_OPTS='--dev -J-Xmx1024M'"
-        - "GEM='ap'"
+        - "GEM=ap"
+    - rvm: jruby-9.1.15.0
+      jdk: oraclejdk8
+      env:
+        - "GEM=am,amo,aj"
   allow_failures:
     - rvm: ruby-head
-    - rvm: jruby-9.0.5.0
+    - rvm: jruby-9.1.15.0
     - env: "GEM=ac:integration"
-    - env: "GEM=ac:integration FAYE=1"
   fast_finish: true
 
 notifications:
@@ -82,12 +133,10 @@ notifications:
     on_success: change
     on_failure: always
     channels:
-      - "irc.freenode.org#rails-contrib"
+      # "irc.freenode.org#rails-contrib"
+      - secure: "QFKSOK7xQiWWqTzYfYm0XWoW7idzuxT57MBW9i9EASyRLEPuDwZEubKRP40Y7wPx7ylQd9lp6kJheeLnrDvvTjFbW3sWv9GDRl4WlOU8sG/Kv7MXAASXlDqzyJxxXTtzLeXz2iwY296kOBuKxKxl923eTvEGeocwH02QGo14LpQ="
   campfire:
     on_success: change
     on_failure: always
     rooms:
       - secure: "YA1alef1ESHWGFNVwvmVGCkMe4cUy4j+UcNvMUESraceiAfVyRMAovlQBGs6\n9kBRm7DHYBUXYC2ABQoJbQRLDr/1B5JPf/M8+Qd7BKu8tcDC03U01SMHFLpO\naOs/HLXcDxtnnpL07tGVsm0zhMc5N8tq4/L3SHxK7Vi+TacwQzI="
-
-git:
-  depth: 1
diff --git a/CONTRIBUTING.md b/CONTRIBUTING.md
index f6ebef7e89..097e2f2f49 100644
--- a/CONTRIBUTING.md
+++ b/CONTRIBUTING.md
@@ -2,6 +2,9 @@
 
 #### **Did you find a bug?**
 
+* **Do not open up a GitHub issue if the bug is a security vulnerability
+  in Rails**, and instead to refer to our [security policy](http://rubyonrails.org/security/).
+
 * **Ensure the bug was not already reported** by searching on GitHub under [Issues](https://github.com/rails/rails/issues).
 
 * If you're unable to find an open issue addressing the problem, [open a new one](https://github.com/rails/rails/issues/new). Be sure to include a **title and clear description**, as much relevant information as possible, and a **code sample** or an **executable test case** demonstrating the expected behavior that is not occurring.
@@ -39,7 +42,6 @@ Changes that are cosmetic in nature and do not add anything substantial to the s
 
 * Please read [Contributing to the Rails Documentation](http://edgeguides.rubyonrails.org/contributing_to_ruby_on_rails.html#contributing-to-the-rails-documentation).
 
-</br>
 Ruby on Rails is a volunteer effort. We encourage you to pitch in and [join the team](http://contributors.rubyonrails.org)!
 
 Thanks! :heart: :heart: :heart:
diff --git a/Gemfile b/Gemfile
index 5650147099..5d75457870 100644
--- a/Gemfile
+++ b/Gemfile
@@ -1,120 +1,151 @@
-source 'https://rubygems.org'
+# frozen_string_literal: true
+
+source "https://rubygems.org"
+
+git_source(:github) { |repo| "https://github.com/#{repo}.git" }
 
 gemspec
 
 # We need a newish Rake since Active Job sets its test tasks' descriptions.
-gem 'rake', '>= 11.1'
+gem "rake", ">= 11.1"
 
 # This needs to be with require false to ensure correct loading order, as it has to
 # be loaded after loading the test library.
-gem 'mocha', '~> 0.14', require: false
+gem "mocha", require: false
+
+gem "capybara", "~> 2.15"
 
-gem 'rack-cache', '~> 1.2'
-gem 'jquery-rails'
-gem 'coffee-rails', github: 'rails/coffee-rails'
-gem 'turbolinks', github: 'turbolinks/turbolinks-rails'
+gem "rack-cache", "~> 1.2"
+gem "coffee-rails"
+gem "sass-rails"
+gem "turbolinks", "~> 5"
 
 # require: false so bcrypt is loaded only when has_secure_password is used.
 # This is to avoid Active Model (and by extension the entire framework)
 # being dependent on a binary library.
-gem 'bcrypt', '~> 3.1.11', require: false
+gem "bcrypt", "~> 3.1.11", require: false
 
 # This needs to be with require false to avoid it being automatically loaded by
 # sprockets.
-gem 'uglifier', '>= 1.3.0', require: false
+gem "uglifier", ">= 1.3.0", require: false
+
+# Explicitly avoid 1.x that doesn't support Ruby 2.4+
+gem "json", ">= 2.0.0"
+
+gem "rubocop", ">= 0.47", require: false
+
+# https://github.com/guard/rb-inotify/pull/79
+gem "rb-inotify", github: "matthewd/rb-inotify", branch: "close-handling", require: false
 
-# Track stable branch of sass because it doesn't have circular require warnings.
-gem 'sass', github: 'sass/sass', branch: 'stable', require: false
+# https://github.com/puma/puma/pull/1345
+gem "stopgap_13632", platforms: :mri if RUBY_VERSION == "2.2.8"
 
 group :doc do
-  gem 'sdoc', '~> 0.4.0'
-  gem 'redcarpet', '~> 3.2.3', platforms: :ruby
-  gem 'w3c_validators'
-  gem 'kindlerb', '0.1.1'
+  gem "sdoc", github: "robin850/sdoc", branch: "upgrade"
+  gem "redcarpet", "~> 3.2.3", platforms: :ruby
+  gem "w3c_validators"
+  gem "kindlerb", "~> 1.2.0"
 end
 
 # Active Support.
-gem 'dalli', '>= 2.2.1'
-gem 'listen', '~> 3.0.5', require: false
+gem "dalli", ">= 2.2.1"
+gem "listen", ">= 3.0.5", "< 3.2", require: false
+gem "libxml-ruby", platforms: :ruby
+
+# for railties app_generator_test
+gem "bootsnap", ">= 1.1.0", require: false
 
 # Active Job.
 group :job do
-  gem 'resque', '< 1.26', require: false
-  gem 'resque-scheduler', require: false
-  gem 'sidekiq', require: false
-  gem 'sucker_punch', require: false
-  gem 'delayed_job', require: false, github: 'collectiveidea/delayed_job'
-  gem 'queue_classic', github: "QueueClassic/queue_classic", branch: 'master', require: false, platforms: :ruby
-  gem 'sneakers', require: false
-  gem 'que', require: false
-  gem 'backburner', require: false
-  #TODO: add qu after it support Rails 5.1
+  gem "resque", require: false
+  gem "resque-scheduler", require: false
+  gem "sidekiq", require: false
+  gem "sucker_punch", require: false
+  gem "delayed_job", require: false
+  gem "queue_classic", github: "QueueClassic/queue_classic", branch: "master", require: false, platforms: :ruby
+  gem "sneakers", require: false
+  gem "que", require: false
+  gem "backburner", require: false
+  # TODO: add qu after it support Rails 5.1
   # gem 'qu-rails', github: "bkeepers/qu", branch: "master", require: false
-  gem 'qu-redis', require: false
-  gem 'delayed_job_active_record', require: false, github: 'collectiveidea/delayed_job_active_record'
-  gem 'sequel', require: false
+  # gem "qu-redis", require: false
+  gem "delayed_job_active_record", require: false
+  gem "sequel", require: false
 end
 
 # Action Cable
 group :cable do
-  gem 'puma', require: false
+  gem "puma", require: false
+
+  gem "hiredis", require: false
+  gem "redis", "~> 4.0", require: false
+
+  gem "redis-namespace"
 
-  gem 'em-hiredis', require: false
-  gem 'hiredis', require: false
-  gem 'redis', require: false
+  gem "websocket-client-simple", github: "matthewd/websocket-client-simple", branch: "close-race", require: false
 
-  gem 'faye-websocket', require: false
+  gem "blade", require: false, platforms: [:ruby]
+  gem "blade-sauce_labs_plugin", require: false, platforms: [:ruby]
+  gem "sprockets-export", require: false
+end
+
+# Active Storage
+group :storage do
+  gem "aws-sdk-s3", require: false
+  gem "google-cloud-storage", "~> 1.8", require: false
+  gem "azure-storage", require: false
 
-  # Lock to 1.1.1 until the fix for https://github.com/faye/faye/issues/394 is released
-  gem 'faye', '1.1.1', require: false
+  gem "mini_magick"
+end
 
-  gem 'blade', require: false
-  gem 'blade-sauce_labs_plugin', require: false
+group :ujs do
+  gem "qunit-selenium"
+  gem "chromedriver-helper"
 end
 
 # Add your own local bundler stuff.
-local_gemfile = File.dirname(__FILE__) + "/.Gemfile"
+local_gemfile = File.expand_path(".Gemfile", __dir__)
 instance_eval File.read local_gemfile if File.exist? local_gemfile
 
 group :test do
-  # FIX: Our test suite isn't ready to run in random order yet.
-  gem 'minitest', '< 5.3.4'
+  gem "minitest", "~> 5.10.0"
+  gem "minitest-bisect"
 
   platforms :mri do
-    gem 'stackprof'
-    gem 'byebug'
+    gem "stackprof"
+    gem "byebug"
   end
 
-  gem 'benchmark-ips'
+  gem "benchmark-ips"
 end
 
 platforms :ruby, :mswin, :mswin64, :mingw, :x64_mingw do
-  gem 'nokogiri', '>= 1.6.8'
+  gem "nokogiri", ">= 1.8.1"
 
   # Needed for compiling the ActionDispatch::Journey parser.
-  gem 'racc', '>=1.4.6', require: false
+  gem "racc", ">=1.4.6", require: false
 
   # Active Record.
-  gem 'sqlite3', '~> 1.3.6'
+  gem "sqlite3", "~> 1.3.6"
 
   group :db do
-    gem 'pg', '>= 0.18.0'
-    gem 'mysql2', '>= 0.4.4'
+    gem "pg", ">= 0.18.0"
+    gem "mysql2", ">= 0.4.4"
   end
 end
 
 platforms :jruby do
-  if ENV['AR_JDBC']
-    gem 'activerecord-jdbcsqlite3-adapter', github: 'jruby/activerecord-jdbc-adapter', branch: 'master'
+  if ENV["AR_JDBC"]
+    gem "activerecord-jdbcsqlite3-adapter", github: "jruby/activerecord-jdbc-adapter", branch: "master"
     group :db do
-      gem 'activerecord-jdbcmysql-adapter', github: 'jruby/activerecord-jdbc-adapter', branch: 'master'
-      gem 'activerecord-jdbcpostgresql-adapter', github: 'jruby/activerecord-jdbc-adapter', branch: 'master'
+      gem "activerecord-jdbcmysql-adapter", github: "jruby/activerecord-jdbc-adapter", branch: "master"
+      gem "activerecord-jdbcpostgresql-adapter", github: "jruby/activerecord-jdbc-adapter", branch: "master"
     end
   else
-    gem 'activerecord-jdbcsqlite3-adapter', '>= 1.3.0'
+    gem "activerecord-jdbcsqlite3-adapter", ">= 1.3.0"
     group :db do
-      gem 'activerecord-jdbcmysql-adapter', '>= 1.3.0'
-      gem 'activerecord-jdbcpostgresql-adapter', '>= 1.3.0'
+      gem "activerecord-jdbcmysql-adapter", ">= 1.3.0"
+      gem "activerecord-jdbcpostgresql-adapter", ">= 1.3.0"
     end
   end
 end
@@ -122,18 +153,18 @@ end
 platforms :rbx do
   # The rubysl-yaml gem doesn't ship with Psych by default as it needs
   # libyaml that isn't always available.
-  gem 'psych', '~> 2.0'
+  gem "psych", "~> 2.0"
 end
 
 # Gems that are necessary for Active Record tests with Oracle.
-if ENV['ORACLE_ENHANCED']
+if ENV["ORACLE_ENHANCED"]
   platforms :ruby do
-    gem 'ruby-oci8', '~> 2.2'
+    gem "ruby-oci8", "~> 2.2"
   end
-  gem 'activerecord-oracle_enhanced-adapter', github: 'rsim/oracle-enhanced', branch: 'master'
+  gem "activerecord-oracle_enhanced-adapter", github: "rsim/oracle-enhanced", branch: "master"
 end
 
 # A gem necessary for Active Record tests with IBM DB.
-gem 'ibm_db' if ENV['IBM_DB']
-gem 'tzinfo-data', platforms: [:mingw, :mswin, :x64_mingw, :jruby]
-gem 'wdm', '>= 0.1.0', platforms: [:mingw, :mswin, :x64_mingw, :mswin64]
+gem "ibm_db" if ENV["IBM_DB"]
+gem "tzinfo-data", platforms: [:mingw, :mswin, :x64_mingw, :jruby]
+gem "wdm", ">= 0.1.0", platforms: [:mingw, :mswin, :x64_mingw, :mswin64]
diff --git a/Gemfile.lock b/Gemfile.lock
index 71f4302a5b..21328870d4 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -1,103 +1,95 @@
 GIT
-  remote: git://github.com/QueueClassic/queue_classic.git
-  revision: c26f2c9f6f6133b946fbcdd7b7ec905a4aca9f94
+  remote: https://github.com/QueueClassic/queue_classic.git
+  revision: cde82d17ded2799ed726dd7b0df6ce1fd4c1b7da
   branch: master
   specs:
     queue_classic (3.2.0.RC1)
-      pg (>= 0.17, < 0.19)
+      pg (>= 0.17, < 0.20)
 
 GIT
-  remote: git://github.com/collectiveidea/delayed_job.git
-  revision: 71f1d5faf934d3057abca942f0d410327bc69087
+  remote: https://github.com/matthewd/rb-inotify.git
+  revision: 856730aad4b285969e8dd621e44808a7c5af4242
+  branch: close-handling
   specs:
-    delayed_job (4.1.1)
-      activesupport (>= 3.0, < 5.1)
+    rb-inotify (0.9.9)
+      ffi (~> 1.0)
 
 GIT
-  remote: git://github.com/collectiveidea/delayed_job_active_record.git
-  revision: 61e688e03b2ef4004b08de6d1e0a123fda8fffad
+  remote: https://github.com/matthewd/websocket-client-simple.git
+  revision: e161305f1a466b9398d86df3b1731b03362da91b
+  branch: close-race
   specs:
-    delayed_job_active_record (4.1.0)
-      activerecord (>= 3.0, < 5.1)
-      delayed_job (>= 3.0, < 5)
-
-GIT
-  remote: git://github.com/rails/coffee-rails.git
-  revision: aa2e623cbda4f3c789a0a15d1f707239e68f5736
-  specs:
-    coffee-rails (4.1.1)
-      coffee-script (>= 2.2.0)
-      railties (>= 4.0.0, < 5.2.x)
+    websocket-client-simple (0.3.0)
+      event_emitter
+      websocket
 
 GIT
-  remote: git://github.com/sass/sass.git
-  revision: 3fda1cbe70d615e7ef96e28db4fd1f8a3ebb5505
-  branch: stable
+  remote: https://github.com/robin850/sdoc.git
+  revision: 0e340352f3ab2f196c8a8743f83c2ee286e4f71c
+  branch: upgrade
   specs:
-    sass (3.4.22)
-
-GIT
-  remote: git://github.com/turbolinks/turbolinks-rails.git
-  revision: 65884729016dbb4d032f12bb01b7e7c1ddeb68ac
-  specs:
-    turbolinks (5.0.0.beta2)
-      turbolinks-source
+    sdoc (1.0.0.rc2)
+      rdoc (~> 5.0)
 
 PATH
   remote: .
   specs:
-    actioncable (5.1.0.alpha)
-      actionpack (= 5.1.0.alpha)
-      nio4r (~> 1.2)
+    actioncable (5.2.0.beta2)
+      actionpack (= 5.2.0.beta2)
+      nio4r (~> 2.0)
       websocket-driver (~> 0.6.1)
-    actionmailer (5.1.0.alpha)
-      actionpack (= 5.1.0.alpha)
-      actionview (= 5.1.0.alpha)
-      activejob (= 5.1.0.alpha)
+    actionmailer (5.2.0.beta2)
+      actionpack (= 5.2.0.beta2)
+      actionview (= 5.2.0.beta2)
+      activejob (= 5.2.0.beta2)
       mail (~> 2.5, >= 2.5.4)
       rails-dom-testing (~> 2.0)
-    actionpack (5.1.0.alpha)
-      actionview (= 5.1.0.alpha)
-      activesupport (= 5.1.0.alpha)
-      rack (~> 2.x)
-      rack-test (~> 0.6.3)
+    actionpack (5.2.0.beta2)
+      actionview (= 5.2.0.beta2)
+      activesupport (= 5.2.0.beta2)
+      rack (~> 2.0)
+      rack-test (>= 0.6.3)
       rails-dom-testing (~> 2.0)
       rails-html-sanitizer (~> 1.0, >= 1.0.2)
-    actionview (5.1.0.alpha)
-      activesupport (= 5.1.0.alpha)
+    actionview (5.2.0.beta2)
+      activesupport (= 5.2.0.beta2)
       builder (~> 3.1)
-      erubis (~> 2.7.0)
+      erubi (~> 1.4)
       rails-dom-testing (~> 2.0)
-      rails-html-sanitizer (~> 1.0, >= 1.0.2)
-    activejob (5.1.0.alpha)
-      activesupport (= 5.1.0.alpha)
+      rails-html-sanitizer (~> 1.0, >= 1.0.3)
+    activejob (5.2.0.beta2)
+      activesupport (= 5.2.0.beta2)
       globalid (>= 0.3.6)
-    activemodel (5.1.0.alpha)
-      activesupport (= 5.1.0.alpha)
-    activerecord (5.1.0.alpha)
-      activemodel (= 5.1.0.alpha)
-      activesupport (= 5.1.0.alpha)
-      arel (~> 7.0)
-    activesupport (5.1.0.alpha)
+    activemodel (5.2.0.beta2)
+      activesupport (= 5.2.0.beta2)
+    activerecord (5.2.0.beta2)
+      activemodel (= 5.2.0.beta2)
+      activesupport (= 5.2.0.beta2)
+      arel (>= 9.0)
+    activestorage (5.2.0.beta2)
+      actionpack (= 5.2.0.beta2)
+      activerecord (= 5.2.0.beta2)
+    activesupport (5.2.0.beta2)
       concurrent-ruby (~> 1.0, >= 1.0.2)
       i18n (~> 0.7)
       minitest (~> 5.1)
       tzinfo (~> 1.1)
-    rails (5.1.0.alpha)
-      actioncable (= 5.1.0.alpha)
-      actionmailer (= 5.1.0.alpha)
-      actionpack (= 5.1.0.alpha)
-      actionview (= 5.1.0.alpha)
-      activejob (= 5.1.0.alpha)
-      activemodel (= 5.1.0.alpha)
-      activerecord (= 5.1.0.alpha)
-      activesupport (= 5.1.0.alpha)
-      bundler (>= 1.3.0, < 2.0)
-      railties (= 5.1.0.alpha)
+    rails (5.2.0.beta2)
+      actioncable (= 5.2.0.beta2)
+      actionmailer (= 5.2.0.beta2)
+      actionpack (= 5.2.0.beta2)
+      actionview (= 5.2.0.beta2)
+      activejob (= 5.2.0.beta2)
+      activemodel (= 5.2.0.beta2)
+      activerecord (= 5.2.0.beta2)
+      activestorage (= 5.2.0.beta2)
+      activesupport (= 5.2.0.beta2)
+      bundler (>= 1.3.0)
+      railties (= 5.2.0.beta2)
       sprockets-rails (>= 2.0.0)
-    railties (5.1.0.alpha)
-      actionpack (= 5.1.0.alpha)
-      activesupport (= 5.1.0.alpha)
+    railties (5.2.0.beta2)
+      actionpack (= 5.2.0.beta2)
+      activesupport (= 5.2.0.beta2)
       method_source
       rake (>= 0.8.7)
       thor (>= 0.18.1, < 2.0)
@@ -105,71 +97,135 @@ PATH
 GEM
   remote: https://rubygems.org/
   specs:
-    addressable (2.4.0)
-    amq-protocol (2.0.1)
-    arel (7.0.0)
-    backburner (1.3.0)
+    activerecord-jdbc-adapter (1.3.24)
+      activerecord (>= 2.2, < 5.0)
+    activerecord-jdbcmysql-adapter (1.3.24)
+      activerecord-jdbc-adapter (~> 1.3.24)
+      jdbc-mysql (>= 5.1.22)
+    activerecord-jdbcpostgresql-adapter (1.3.24)
+      activerecord-jdbc-adapter (~> 1.3.24)
+      jdbc-postgres (~> 9.1, <= 9.4.1206)
+    activerecord-jdbcsqlite3-adapter (1.3.24)
+      activerecord-jdbc-adapter (~> 1.3.24)
+      jdbc-sqlite3 (>= 3.7.2, < 3.9)
+    addressable (2.5.2)
+      public_suffix (>= 2.0.2, < 4.0)
+    amq-protocol (2.2.0)
+    archive-zip (0.7.0)
+      io-like (~> 0.3.0)
+    arel (9.0.0)
+    ast (2.3.0)
+    aws-partitions (1.20.0)
+    aws-sdk-core (3.3.0)
+      aws-partitions (~> 1.0)
+      aws-sigv4 (~> 1.0)
+      jmespath (~> 1.0)
+    aws-sdk-kms (1.1.0)
+      aws-sdk-core (~> 3)
+      aws-sigv4 (~> 1.0)
+    aws-sdk-s3 (1.2.0)
+      aws-sdk-core (~> 3)
+      aws-sdk-kms (~> 1)
+      aws-sigv4 (~> 1.0)
+    aws-sigv4 (1.0.1)
+    azure-core (0.1.11)
+      faraday (~> 0.9)
+      faraday_middleware (~> 0.10)
+      nokogiri (~> 1.6)
+    azure-storage (0.12.3.preview)
+      azure-core (~> 0.1)
+      faraday (~> 0.9)
+      faraday_middleware (~> 0.10)
+    backburner (1.4.1)
       beaneater (~> 1.0)
+      concurrent-ruby (~> 1.0.1)
       dante (> 0.1.5)
     bcrypt (3.1.11)
+    bcrypt (3.1.11-java)
     bcrypt (3.1.11-x64-mingw32)
     bcrypt (3.1.11-x86-mingw32)
     beaneater (1.0.0)
-    benchmark-ips (2.6.1)
-    blade (0.5.6)
+    benchmark-ips (2.7.2)
+    blade (0.7.1)
       activesupport (>= 3.0.0)
-      blade-qunit_adapter (~> 1.20.0)
+      blade-qunit_adapter (~> 2.0.1)
       coffee-script
       coffee-script-source
       curses (~> 1.0.0)
       eventmachine
       faye
       sprockets (>= 3.0)
-      sprockets-export (~> 0.9.1)
       thin (>= 1.6.0)
-      thor (~> 0.19.1)
+      thor (>= 0.19.1)
       useragent (~> 0.16.7)
-    blade-qunit_adapter (1.20.0)
-    blade-sauce_labs_plugin (0.5.2)
+    blade-qunit_adapter (2.0.1)
+    blade-sauce_labs_plugin (0.7.2)
       childprocess
       faraday
       selenium-webdriver
-    builder (3.2.2)
-    bunny (2.2.2)
-      amq-protocol (>= 2.0.1)
-    byebug (8.2.5)
-    childprocess (0.5.9)
+    bootsnap (1.1.2)
+      msgpack (~> 1.0)
+    bootsnap (1.1.2-java)
+      msgpack (~> 1.0)
+    builder (3.2.3)
+    bunny (2.6.6)
+      amq-protocol (>= 2.1.0)
+    byebug (9.0.6)
+    capybara (2.15.1)
+      addressable
+      mini_mime (>= 0.1.3)
+      nokogiri (>= 1.3.3)
+      rack (>= 1.0.0)
+      rack-test (>= 0.5.4)
+      xpath (~> 2.0)
+    childprocess (0.7.1)
       ffi (~> 1.0, >= 1.0.11)
+    chromedriver-helper (1.1.0)
+      archive-zip (~> 0.7.0)
+      nokogiri (~> 1.6)
+    coffee-rails (4.2.2)
+      coffee-script (>= 2.2.0)
+      railties (>= 4.0.0)
     coffee-script (2.4.1)
       coffee-script-source
       execjs
-    coffee-script-source (1.10.0)
-    concurrent-ruby (1.0.2)
-    connection_pool (2.2.0)
-    cookiejar (0.3.0)
+    coffee-script-source (1.12.2)
+    concurrent-ruby (1.0.5)
+    concurrent-ruby (1.0.5-java)
+    connection_pool (2.2.1)
+    cookiejar (0.3.3)
+    crass (1.0.3)
     curses (1.0.2)
-    daemons (1.2.3)
+    daemons (1.2.4)
     dalli (2.7.6)
     dante (0.2.0)
-    em-hiredis (0.3.1)
-      eventmachine (~> 1.0)
-      hiredis (~> 0.6.0)
-    em-http-request (1.1.3)
+    declarative (0.0.10)
+    declarative-option (0.1.0)
+    delayed_job (4.1.4)
+      activesupport (>= 3.0, < 5.2)
+    delayed_job_active_record (4.1.2)
+      activerecord (>= 3.0, < 5.2)
+      delayed_job (>= 3.0, < 5)
+    digest-crc (0.4.1)
+    em-http-request (1.1.5)
       addressable (>= 2.3.4)
-      cookiejar (<= 0.3.0)
+      cookiejar (!= 0.3.1)
       em-socksify (>= 0.3)
       eventmachine (>= 1.0.3)
       http_parser.rb (>= 0.6.0)
     em-socksify (0.3.1)
       eventmachine (>= 1.0.0.beta.4)
-    erubis (2.7.0)
-    eventmachine (1.2.0.1)
-    eventmachine (1.2.0.1-x64-mingw32)
-    eventmachine (1.2.0.1-x86-mingw32)
+    erubi (1.7.0)
+    et-orbi (1.0.8)
+      tzinfo
+    event_emitter (0.2.6)
+    eventmachine (1.2.5)
     execjs (2.7.0)
-    faraday (0.9.2)
+    faraday (0.13.1)
       multipart-post (>= 1.2, < 3)
-    faye (1.1.1)
+    faraday_middleware (0.12.2)
+      faraday (>= 0.7.4, < 1.0)
+    faye (1.2.4)
       cookiejar (>= 0.3.0)
       em-http-request (>= 0.3.0)
       eventmachine (>= 0.12.0)
@@ -177,170 +233,265 @@ GEM
       multi_json (>= 1.0.0)
       rack (>= 1.0.0)
       websocket-driver (>= 0.5.1)
-    faye-websocket (0.10.4)
+    faye-websocket (0.10.7)
       eventmachine (>= 0.12.0)
       websocket-driver (>= 0.5.1)
-    ffi (1.9.10)
-    ffi (1.9.10-x64-mingw32)
-    ffi (1.9.10-x86-mingw32)
-    globalid (0.3.6)
-      activesupport (>= 4.1.0)
+    ffi (1.9.18)
+    ffi (1.9.18-java)
+    ffi (1.9.18-x64-mingw32)
+    ffi (1.9.18-x86-mingw32)
+    globalid (0.4.1)
+      activesupport (>= 4.2.0)
+    google-api-client (0.17.3)
+      addressable (~> 2.5, >= 2.5.1)
+      googleauth (>= 0.5, < 0.7.0)
+      httpclient (>= 2.8.1, < 3.0)
+      mime-types (~> 3.0)
+      representable (~> 3.0)
+      retriable (>= 2.0, < 4.0)
+    google-cloud-core (1.1.0)
+      google-cloud-env (~> 1.0)
+    google-cloud-env (1.0.1)
+      faraday (~> 0.11)
+    google-cloud-storage (1.9.0)
+      digest-crc (~> 0.4)
+      google-api-client (~> 0.17.0)
+      google-cloud-core (~> 1.1)
+      googleauth (~> 0.6.2)
+    googleauth (0.6.2)
+      faraday (~> 0.12)
+      jwt (>= 1.4, < 3.0)
+      logging (~> 2.0)
+      memoist (~> 0.12)
+      multi_json (~> 1.11)
+      os (~> 0.9)
+      signet (~> 0.7)
     hiredis (0.6.1)
+    hiredis (0.6.1-java)
     http_parser.rb (0.6.0)
-    i18n (0.7.0)
-    jquery-rails (4.1.1)
-      rails-dom-testing (>= 1, < 3)
-      railties (>= 4.2.0)
-      thor (>= 0.14, < 2.0)
-    json (1.8.3)
-    kindlerb (0.1.1)
+    httpclient (2.8.3)
+    i18n (0.9.1)
+      concurrent-ruby (~> 1.0)
+    io-like (0.3.0)
+    jdbc-mysql (5.1.44)
+    jdbc-postgres (9.4.1206)
+    jdbc-sqlite3 (3.8.11.2)
+    jmespath (1.3.1)
+    json (2.1.0)
+    json (2.1.0-java)
+    jwt (2.1.0)
+    kindlerb (1.2.0)
       mustache
       nokogiri
-    listen (3.0.7)
-      rb-fsevent (>= 0.9.3)
-      rb-inotify (>= 0.9.7)
-    loofah (2.0.3)
+    libxml-ruby (3.0.0)
+    listen (3.1.5)
+      rb-fsevent (~> 0.9, >= 0.9.4)
+      rb-inotify (~> 0.9, >= 0.9.7)
+      ruby_dep (~> 1.2)
+    little-plugger (1.1.4)
+    logging (2.2.2)
+      little-plugger (~> 1.1)
+      multi_json (~> 1.10)
+    loofah (2.1.1)
+      crass (~> 1.0.2)
       nokogiri (>= 1.5.9)
-    mail (2.6.4)
-      mime-types (>= 1.16, < 4)
+    mail (2.7.0)
+      mini_mime (>= 0.1.1)
+    memoist (0.16.0)
     metaclass (0.0.4)
-    method_source (0.8.2)
-    mime-types (3.0)
+    method_source (0.9.0)
+    mime-types (3.1)
       mime-types-data (~> 3.2015)
-    mime-types-data (3.2016.0221)
-    mini_portile2 (2.1.0)
-    minitest (5.3.3)
-    mocha (0.14.0)
+    mime-types-data (3.2016.0521)
+    mini_magick (4.8.0)
+    mini_mime (0.1.4)
+    mini_portile2 (2.3.0)
+    minitest (5.10.3)
+    minitest-bisect (1.4.0)
+      minitest-server (~> 1.0)
+      path_expander (~> 1.0)
+    minitest-server (1.0.4)
+      minitest (~> 5.0)
+    mocha (1.3.0)
       metaclass (~> 0.0.1)
     mono_logger (1.1.0)
-    multi_json (1.12.1)
+    msgpack (1.1.0)
+    msgpack (1.1.0-java)
+    msgpack (1.1.0-x64-mingw32)
+    msgpack (1.1.0-x86-mingw32)
+    multi_json (1.12.2)
     multipart-post (2.0.0)
-    mustache (1.0.3)
-    mysql2 (0.4.4)
-    mysql2 (0.4.4-x64-mingw32)
-    mysql2 (0.4.4-x86-mingw32)
-    nio4r (1.2.1)
-    nokogiri (1.6.8)
-      mini_portile2 (~> 2.1.0)
-      pkg-config (~> 1.1.7)
-    nokogiri (1.6.8-x64-mingw32)
-      mini_portile2 (~> 2.1.0)
-      pkg-config (~> 1.1.7)
-    nokogiri (1.6.8-x86-mingw32)
-      mini_portile2 (~> 2.1.0)
-      pkg-config (~> 1.1.7)
-    pg (0.18.4)
-    pg (0.18.4-x64-mingw32)
-    pg (0.18.4-x86-mingw32)
-    pkg-config (1.1.7)
-    psych (2.0.17)
-    puma (3.4.0)
-    qu (0.2.0)
-      multi_json
-    qu-redis (0.2.0)
-      qu (= 0.2.0)
-      redis-namespace
-      simple_uuid
-    que (0.11.4)
+    mustache (1.0.5)
+    mustermann (1.0.0)
+    mysql2 (0.4.9)
+    mysql2 (0.4.9-x64-mingw32)
+    mysql2 (0.4.9-x86-mingw32)
+    nio4r (2.1.0)
+    nio4r (2.1.0-java)
+    nokogiri (1.8.1)
+      mini_portile2 (~> 2.3.0)
+    nokogiri (1.8.1-java)
+    nokogiri (1.8.1-x64-mingw32)
+      mini_portile2 (~> 2.3.0)
+    nokogiri (1.8.1-x86-mingw32)
+      mini_portile2 (~> 2.3.0)
+    os (0.9.6)
+    parallel (1.12.0)
+    parser (2.4.0.0)
+      ast (~> 2.2)
+    path_expander (1.0.2)
+    pg (0.19.0)
+    pg (0.19.0-x64-mingw32)
+    pg (0.19.0-x86-mingw32)
+    powerpack (0.1.1)
+    psych (2.2.4)
+    public_suffix (3.0.1)
+    puma (3.9.1)
+    puma (3.9.1-java)
+    que (0.14.0)
+    qunit-selenium (0.0.4)
+      selenium-webdriver
+      thor
     racc (1.4.14)
-    rack (2.0.0.rc1)
-      json
-    rack-cache (1.6.1)
+    rack (2.0.3)
+    rack-cache (1.7.0)
       rack (>= 0.4)
-    rack-test (0.6.3)
-      rack (>= 1.0)
-    rails-dom-testing (2.0.0)
-      activesupport (>= 4.2.0, < 6.0)
-      nokogiri (~> 1.6.0)
+    rack-protection (2.0.0)
+      rack
+    rack-test (0.8.0)
+      rack (>= 1.0, < 3)
+    rails-dom-testing (2.0.3)
+      activesupport (>= 4.2.0)
+      nokogiri (>= 1.6)
     rails-html-sanitizer (1.0.3)
       loofah (~> 2.0)
-    rake (11.1.2)
-    rb-fsevent (0.9.7)
-    rb-inotify (0.9.7)
-      ffi (>= 0.5.0)
-    rdoc (4.2.2)
-      json (~> 1.4)
+    rainbow (2.2.2)
+      rake
+    rake (12.2.1)
+    rb-fsevent (0.10.2)
+    rdoc (5.1.0)
     redcarpet (3.2.3)
-    redis (3.3.0)
-    redis-namespace (1.5.2)
-      redis (~> 3.0, >= 3.0.4)
-    resque (1.25.2)
+    redis (4.0.1)
+    redis-namespace (1.6.0)
+      redis (>= 3.0.4)
+    representable (3.0.4)
+      declarative (< 0.1.0)
+      declarative-option (< 0.2.0)
+      uber (< 0.2.0)
+    resque (1.27.4)
       mono_logger (~> 1.0)
       multi_json (~> 1.0)
       redis-namespace (~> 1.3)
       sinatra (>= 0.9.2)
       vegas (~> 0.1.2)
-    resque-scheduler (4.2.0)
+    resque-scheduler (4.3.1)
       mono_logger (~> 1.0)
-      redis (~> 3.0)
-      resque (~> 1.25)
+      redis (>= 3.3, < 5)
+      resque (~> 1.26)
       rufus-scheduler (~> 3.2)
-    rubyzip (1.2.0)
-    rufus-scheduler (3.2.1)
-    sdoc (0.4.1)
-      json (~> 1.7, >= 1.7.7)
-      rdoc (~> 4.0)
-    selenium-webdriver (2.53.0)
+    retriable (3.1.1)
+    rubocop (0.51.0)
+      parallel (~> 1.10)
+      parser (>= 2.3.3.1, < 3.0)
+      powerpack (~> 0.1)
+      rainbow (>= 2.2.2, < 3.0)
+      ruby-progressbar (~> 1.7)
+      unicode-display_width (~> 1.0, >= 1.0.1)
+    ruby-progressbar (1.9.0)
+    ruby_dep (1.5.0)
+    rubyzip (1.2.1)
+    rufus-scheduler (3.4.2)
+      et-orbi (~> 1.0)
+    sass (3.5.3)
+      sass-listen (~> 4.0.0)
+    sass-listen (4.0.0)
+      rb-fsevent (~> 0.9, >= 0.9.4)
+      rb-inotify (~> 0.9, >= 0.9.7)
+    sass-rails (5.0.7)
+      railties (>= 4.0.0, < 6)
+      sass (~> 3.1)
+      sprockets (>= 2.8, < 4.0)
+      sprockets-rails (>= 2.0, < 4.0)
+      tilt (>= 1.1, < 3)
+    selenium-webdriver (3.5.1)
       childprocess (~> 0.5)
       rubyzip (~> 1.0)
-      websocket (~> 1.0)
-    sequel (4.34.0)
+    sequel (4.49.0)
     serverengine (1.5.11)
       sigdump (~> 0.2.2)
-    sidekiq (4.1.2)
+    sidekiq (5.0.5)
       concurrent-ruby (~> 1.0)
       connection_pool (~> 2.2, >= 2.2.0)
-      redis (~> 3.2, >= 3.2.1)
+      rack-protection (>= 1.5.0)
+      redis (>= 3.3.4, < 5)
     sigdump (0.2.4)
-    simple_uuid (0.4.0)
-    sinatra (1.0)
-      rack (>= 1.0)
-    sneakers (2.3.5)
-      bunny (~> 2.2.0)
+    signet (0.8.1)
+      addressable (~> 2.3)
+      faraday (~> 0.9)
+      jwt (>= 1.5, < 3.0)
+      multi_json (~> 1.10)
+    sinatra (2.0.0)
+      mustermann (~> 1.0)
+      rack (~> 2.0)
+      rack-protection (= 2.0.0)
+      tilt (~> 2.0)
+    sneakers (2.5.0)
+      bunny (~> 2.6.4)
       serverengine (~> 1.5.11)
       thor
       thread (~> 0.1.7)
-    sprockets (3.6.1)
+    sprockets (3.7.1)
       concurrent-ruby (~> 1.0)
       rack (> 1, < 3)
-    sprockets-export (0.9.1)
-    sprockets-rails (3.0.4)
+    sprockets-export (1.0.0)
+    sprockets-rails (3.2.0)
       actionpack (>= 4.0)
       activesupport (>= 4.0)
       sprockets (>= 3.0.0)
-    sqlite3 (1.3.11)
-    sqlite3 (1.3.11-x64-mingw32)
-    sqlite3 (1.3.11-x86-mingw32)
-    stackprof (0.2.9)
+    sqlite3 (1.3.13)
+    sqlite3 (1.3.13-x64-mingw32)
+    sqlite3 (1.3.13-x86-mingw32)
+    stackprof (0.2.10)
     sucker_punch (2.0.2)
       concurrent-ruby (~> 1.0.0)
-    thin (1.7.0)
+    thin (1.7.2)
       daemons (~> 1.0, >= 1.0.9)
       eventmachine (~> 1.0, >= 1.0.4)
       rack (>= 1, < 3)
-    thor (0.19.1)
+    thor (0.20.0)
     thread (0.1.7)
-    thread_safe (0.3.5)
-    turbolinks-source (5.0.0.beta4)
-    tzinfo (1.2.2)
+    thread_safe (0.3.6)
+    thread_safe (0.3.6-java)
+    tilt (2.0.8)
+    turbolinks (5.0.1)
+      turbolinks-source (~> 5)
+    turbolinks-source (5.0.3)
+    tzinfo (1.2.3)
       thread_safe (~> 0.1)
-    tzinfo-data (1.2016.4)
+    tzinfo-data (1.2017.2)
       tzinfo (>= 1.0.0)
-    uglifier (3.0.0)
+    uber (0.1.0)
+    uglifier (3.2.0)
       execjs (>= 0.3.0, < 3)
-    useragent (0.16.7)
+    unicode-display_width (1.3.0)
+    useragent (0.16.8)
     vegas (0.1.11)
       rack (>= 1.0.0)
-    w3c_validators (1.2)
-      json
-      nokogiri
+    w3c_validators (1.3.3)
+      json (>= 1.8)
+      nokogiri (~> 1.6)
     wdm (0.1.1)
-    websocket (1.2.3)
-    websocket-driver (0.6.4)
+    websocket (1.2.4)
+    websocket-driver (0.6.5)
+      websocket-extensions (>= 0.1.0)
+    websocket-driver (0.6.5-java)
       websocket-extensions (>= 0.1.0)
     websocket-extensions (0.1.2)
+    xpath (2.1.0)
+      nokogiri (~> 1.3)
 
 PLATFORMS
+  java
   ruby
   x64-mingw32
   x86-mingw32
@@ -349,54 +500,65 @@ DEPENDENCIES
   activerecord-jdbcmysql-adapter (>= 1.3.0)
   activerecord-jdbcpostgresql-adapter (>= 1.3.0)
   activerecord-jdbcsqlite3-adapter (>= 1.3.0)
+  aws-sdk-s3
+  azure-storage
   backburner
   bcrypt (~> 3.1.11)
   benchmark-ips
   blade
   blade-sauce_labs_plugin
+  bootsnap (>= 1.1.0)
   byebug
-  coffee-rails!
+  capybara (~> 2.15)
+  chromedriver-helper
+  coffee-rails
   dalli (>= 2.2.1)
-  delayed_job!
-  delayed_job_active_record!
-  em-hiredis
-  faye (= 1.1.1)
-  faye-websocket
+  delayed_job
+  delayed_job_active_record
+  google-cloud-storage (~> 1.8)
   hiredis
-  jquery-rails
-  kindlerb (= 0.1.1)
-  listen (~> 3.0.5)
-  minitest (< 5.3.4)
-  mocha (~> 0.14)
+  json (>= 2.0.0)
+  kindlerb (~> 1.2.0)
+  libxml-ruby
+  listen (>= 3.0.5, < 3.2)
+  mini_magick
+  minitest (~> 5.10.0)
+  minitest-bisect
+  mocha
   mysql2 (>= 0.4.4)
-  nokogiri (>= 1.6.8)
+  nokogiri (>= 1.8.1)
   pg (>= 0.18.0)
   psych (~> 2.0)
   puma
-  qu-redis
   que
   queue_classic!
+  qunit-selenium
   racc (>= 1.4.6)
   rack-cache (~> 1.2)
   rails!
   rake (>= 11.1)
+  rb-inotify!
   redcarpet (~> 3.2.3)
-  redis
-  resque (< 1.26)
+  redis (~> 4.0)
+  redis-namespace
+  resque
   resque-scheduler
-  sass!
-  sdoc (~> 0.4.0)
+  rubocop (>= 0.47)
+  sass-rails
+  sdoc!
   sequel
   sidekiq
   sneakers
+  sprockets-export
   sqlite3 (~> 1.3.6)
   stackprof
   sucker_punch
-  turbolinks!
+  turbolinks (~> 5)
   tzinfo-data
   uglifier (>= 1.3.0)
   w3c_validators
   wdm (>= 0.1.0)
+  websocket-client-simple!
 
 BUNDLED WITH
-   1.11.2
+   1.16.1
diff --git a/MIT-LICENSE b/MIT-LICENSE
new file mode 100644
index 0000000000..8f769c0767
--- /dev/null
+++ b/MIT-LICENSE
@@ -0,0 +1,20 @@
+Copyright (c) 2005-2018 David Heinemeier Hansson
+
+Permission is hereby granted, free of charge, to any person obtaining
+a copy of this software and associated documentation files (the
+"Software"), to deal in the Software without restriction, including
+without limitation the rights to use, copy, modify, merge, publish,
+distribute, sublicense, and/or sell copies of the Software, and to
+permit persons to whom the Software is furnished to do so, subject to
+the following conditions:
+
+The above copyright notice and this permission notice shall be
+included in all copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
+LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
+OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
diff --git a/RAILS_VERSION b/RAILS_VERSION
index 8ea1016081..5d41efd0ef 100644
--- a/RAILS_VERSION
+++ b/RAILS_VERSION
@@ -1 +1 @@
-5.1.0.alpha
+5.2.0.beta2
diff --git a/README.md b/README.md
index a2b726ea6c..030dd405cb 100644
--- a/README.md
+++ b/README.md
@@ -40,6 +40,8 @@ to generate and send emails; Active Job ([README](activejob/README.md)), a
 framework for declaring jobs and making them run on a variety of queueing
 backends; Action Cable ([README](actioncable/README.md)), a framework to
 integrate WebSockets with a Rails application;
+Active Storage ([README](activestorage/README.md)), a library to attach cloud
+and local files to Rails applications;
 and Active Support ([README](activesupport/README.rdoc)), a collection
 of utility classes and standard library extensions that are useful for Rails,
 and may also be used independently outside Rails.
@@ -71,13 +73,19 @@ and may also be used independently outside Rails.
     * [Getting Started with Rails](http://guides.rubyonrails.org/getting_started.html)
     * [Ruby on Rails Guides](http://guides.rubyonrails.org)
     * [The API Documentation](http://api.rubyonrails.org)
-    * [Ruby on Rails Tutorial](http://www.railstutorial.org/book)
+    * [Ruby on Rails Tutorial](https://www.railstutorial.org/book)
 
 ## Contributing
 
+[![Code Triage Badge](https://www.codetriage.com/rails/rails/badges/users.svg)](https://www.codetriage.com/rails/rails)
+
 We encourage you to contribute to Ruby on Rails! Please check out the
 [Contributing to Ruby on Rails guide](http://edgeguides.rubyonrails.org/contributing_to_ruby_on_rails.html) for guidelines about how to proceed. [Join us!](http://contributors.rubyonrails.org)
 
+Trying to report a possible security vulnerability in Rails? Please
+check out our [security policy](http://rubyonrails.org/security/) for
+guidelines about how to proceed.
+
 Everyone interacting in Rails and its sub-projects' codebases, issue trackers, chat rooms, and mailing lists is expected to follow the Rails [code of conduct](http://rubyonrails.org/conduct/).
 
 ## Code Status
@@ -86,4 +94,4 @@ Everyone interacting in Rails and its sub-projects' codebases, issue trackers, c
 
 ## License
 
-Ruby on Rails is released under the [MIT License](http://www.opensource.org/licenses/MIT).
+Ruby on Rails is released under the [MIT License](https://opensource.org/licenses/MIT).
diff --git a/RELEASING_RAILS.md b/RELEASING_RAILS.md
index 4e6b811d3e..c61fe7eb13 100644
--- a/RELEASING_RAILS.md
+++ b/RELEASING_RAILS.md
@@ -1,35 +1,35 @@
 # Releasing Rails
 
-In this document, we'll cover the steps necessary to release Rails.  Each
-section contains steps to take during that time before the release.  The times
-suggested in each header are just that: suggestions.  However, they should
+In this document, we'll cover the steps necessary to release Rails. Each
+section contains steps to take during that time before the release. The times
+suggested in each header are just that: suggestions. However, they should
 really be considered as minimums.
 
 ## 10 Days before release
 
-Today is mostly coordination tasks.  Here are the things you must do today:
+Today is mostly coordination tasks. Here are the things you must do today:
 
-### Is the CI green?  If not, make it green. (See "Fixing the CI")
+### Is the CI green? If not, make it green. (See "Fixing the CI")
 
-Do not release with a Red CI.  You can find the CI status here:
+Do not release with a Red CI. You can find the CI status here:
 
 ```
 http://travis-ci.org/rails/rails
 ```
 
-### Is Sam Ruby happy?  If not, make him happy.
+### Is Sam Ruby happy? If not, make him happy.
 
 Sam Ruby keeps a [test suite](https://github.com/rubys/awdwr) that makes
 sure the code samples in his book
 ([Agile Web Development with Rails](https://pragprog.com/titles/rails5/agile-web-development-with-rails-5th-edition))
-all work.  These are valuable system tests
-for Rails.  You can check the status of these tests here:
+all work. These are valuable system tests
+for Rails. You can check the status of these tests here:
 
 [http://intertwingly.net/projects/dashboard.html](http://intertwingly.net/projects/dashboard.html)
 
 Do not release with Red AWDwR tests.
 
-### Do we have any Git dependencies?  If so, contact those authors.
+### Do we have any Git dependencies? If so, contact those authors.
 
 Having Git dependencies indicates that we depend on unreleased code.
 Obviously Rails cannot be released when it depends on unreleased code.
@@ -38,12 +38,12 @@ suits them.
 
 ### Contact the security team (either tenderlove or rafaelfranca)
 
-Let them know of your plans to release.  There may be security issues to be
+Let them know of your plans to release. There may be security issues to be
 addressed, and that can impact your release date.
 
 ### Notify implementors.
 
-Ruby implementors have high stakes in making sure Rails works.  Be kind and
+Ruby implementors have high stakes in making sure Rails works. Be kind and
 give them a heads up that Rails will be released soonish.
 
 This is only required for major and minor releases, bugfix releases aren't a
@@ -58,20 +58,20 @@ lists:
 
 Implementors will love you and help you.
 
-### 3 Days before release
+## 3 Days before release
 
-This is when you should release the release candidate.  Here are your tasks
+This is when you should release the release candidate. Here are your tasks
 for today:
 
-### Is the CI green?  If not, make it green.
+### Is the CI green? If not, make it green.
 
-### Is Sam Ruby happy?  If not, make him happy.
+### Is Sam Ruby happy? If not, make him happy.
 
-### Contact the security team.  CVE emails must be sent on this day.
+### Contact the security team. CVE emails must be sent on this day.
 
 ### Create a release branch.
 
-From the stable branch, create a release branch.  For example, if you're
+From the stable branch, create a release branch. For example, if you're
 releasing Rails 3.0.10, do this:
 
 ```
@@ -82,7 +82,7 @@ Switched to a new branch '3-0-10'
 
 ### Update each CHANGELOG.
 
-Many times commits are made without the CHANGELOG being updated.  You should
+Many times commits are made without the CHANGELOG being updated. You should
 review the commits since the last release, and fill in any missing information
 for each CHANGELOG.
 
@@ -96,56 +96,60 @@ If you're doing a stable branch release, you should also ensure that all of
 the CHANGELOG entries in the stable branch are also synced to the master
 branch.
 
-### Update the RAILS_VERSION file to include the RC.
+### Put the new version in the RAILS_VERSION file.
 
-### Build and test the gem.
+Include an RC number if appropriate, e.g. `6.0.0.rc1`.
 
-Run `rake install` to generate the gems and install them locally. Then try
-generating a new app and ensure that nothing explodes.
+### Build and test the gem.
 
-Verify that Action Cable's package.json is updated with the RC version.
+Run `rake verify` to generate the gems and install them locally. `verify` also
+generates a Rails app with a migration and boots it to smoke test with in your
+browser.
 
 This will stop you from looking silly when you push an RC to rubygems.org and
 then realize it is broken.
 
 ### Release to RubyGems and NPM.
 
-IMPORTANT: The Action Cable client is released as an NPM package, so you must
-have Node.js installed, have an NPM account (npmjs.com), and be an actioncable
-package owner (`npm owner ls actioncable`) to do a full release. Do not release
-until you're set up with NPM!
+IMPORTANT: The Action Cable client and Action View's UJS adapter are released
+as NPM packages, so you must have Node.js installed, have an NPM account
+(npmjs.com), and be a package owner for `actioncable` and `rails-ujs` (you can
+check this via `npm owner ls actioncable` and `npm owner ls rails-ujs`) in
+order to do a full release. Do not release until you're set up with NPM!
+
+The release task will sign the release tag. If you haven't got commit signing
+set up, use https://git-scm.com/book/tr/v2/Git-Tools-Signing-Your-Work as a
+guide. You can generate keys with the GPG suite from here: https://gpgtools.org.
+
+Run `rake changelog:header` to put a header with the new version in every
+CHANGELOG. Don't commit this, the release task handles it.
 
 Run `rake release`. This will populate the gemspecs and NPM package.json with
 the current RAILS_VERSION, commit the changes, tag it, and push the gems to
 rubygems.org.
 
-Here are the commands that `rake release` uses so you can understand what to do
-in case anything goes wrong:
-
-```
-$ rake all:build
-$ git commit -am'updating RAILS_VERSION'
-$ git tag -m 'v3.0.10.rc1 release' v3.0.10.rc1
-$ git push
-$ git push --tags
-$ for i in $(ls pkg); do gem push $i; npm publish; done
-```
-
 ### Send Rails release announcements
 
 Write a release announcement that includes the version, changes, and links to
-GitHub where people can find the specific commit list.  Here are the mailing
+GitHub where people can find the specific commit list. Here are the mailing
 lists where you should announce:
 
 * rubyonrails-core@googlegroups.com
 * rubyonrails-talk@googlegroups.com
 * ruby-talk@ruby-lang.org
 
-Use Markdown format for your announcement.  Remember to ask people to report
+Use Markdown format for your announcement. Remember to ask people to report
 issues with the release candidate to the rails-core mailing list.
 
+NOTE: For patch releases, there's a `rake announce` task to generate the release
+post. It supports multiple patch releases too:
+
+```
+VERSIONS="5.0.5.rc1,5.1.3.rc1" rake announce
+```
+
 IMPORTANT: If any users experience regressions when using the release
-candidate, you *must* postpone the release.  Bugfix releases *should not*
+candidate, you *must* postpone the release. Bugfix releases *should not*
 break existing applications.
 
 ### Post the announcement to the Rails blog.
@@ -163,12 +167,12 @@ Check the rails-core mailing list and the GitHub issue list for regressions in
 the RC.
 
 If any regressions are found, fix the regressions and repeat the release
-candidate process.  We will not release the final until 72 hours after the
-last release candidate has been pushed.  This means that if users find
+candidate process. We will not release the final until 72 hours after the
+last release candidate has been pushed. This means that if users find
 regressions, the scheduled release date must be postponed.
 
-When you fix the regressions, do not create a new branch.  Fix them on the
-stable branch, then cherry pick the commit to your release branch.  No other
+When you fix the regressions, do not create a new branch. Fix them on the
+stable branch, then cherry pick the commit to your release branch. No other
 commits should be added to the release branch besides regression fixing commits.
 
 ## Day of release
@@ -179,7 +183,7 @@ more explanation on a particular step, see the RC steps.
 Today, do this stuff in this order:
 
 * Apply security patches to the release branch
-* Update CHANGELOG with security fixes.
+* Update CHANGELOG with security fixes
 * Update RAILS_VERSION to remove the rc
 * Build and test the gem
 * Release the gems
@@ -201,12 +205,12 @@ Email the security reports to:
 * oss-security@lists.openwall.com
 
 Be sure to note the security fixes in your announcement along with CVE numbers
-and links to each patch.  Some people may not be able to upgrade right away,
+and links to each patch. Some people may not be able to upgrade right away,
 so we need to give them the security fixes in patch form.
 
 * Blog announcements
 * Twitter announcements
-* Merge the release branch to the stable branch.
+* Merge the release branch to the stable branch
 * Drink beer (or other cocktail)
 
 ## Misc
diff --git a/Rakefile b/Rakefile
index 1d70ce96ea..a67f8fd028 100644
--- a/Rakefile
+++ b/Rakefile
@@ -1,20 +1,25 @@
-require 'net/http'
+# frozen_string_literal: true
 
-$:.unshift File.expand_path('..', __FILE__)
+require "net/http"
+
+$:.unshift __dir__
 require "tasks/release"
-require 'railties/lib/rails/api/task'
+require "railties/lib/rails/api/task"
 
 desc "Build gem files for all projects"
-task :build => "all:build"
+task build: "all:build"
+
+desc "Build, install and verify the gem files in a generated Rails app."
+task verify: "all:verify"
 
 desc "Prepare the release"
-task :prep_release => "all:prep_release"
+task prep_release: "all:prep_release"
 
 desc "Release all gems to rubygems and create a tag"
-task :release => "all:release"
+task release: "all:release"
 
-desc 'Run all tests by default'
-task :default => %w(test test:isolated)
+desc "Run all tests by default"
+task default: %w(test test:isolated)
 
 %w(test test:isolated package gem).each do |task_name|
   desc "Run #{task_name} task for all projects"
@@ -23,9 +28,6 @@ task :default => %w(test test:isolated)
     FRAMEWORKS.each do |project|
       system(%(cd #{project} && #{$0} #{task_name} --trace)) || errors << project
     end
-    if task_name =~ /test/
-      system(%(cd actioncable && env FAYE=1 #{$0} #{task_name} --trace)) || errors << 'actioncable-faye'
-    end
     fail("Errors in #{errors.join(', ')}") unless errors.empty?
   end
 end
@@ -36,21 +38,20 @@ task :smoke do
     system %(cd #{project} && #{$0} test:isolated --trace)
   end
   system %(cd activerecord && #{$0} sqlite3:isolated_test --trace)
-  system %(cd actioncable && env FAYE=1 #{$0} test:isolated --trace)
 end
 
 desc "Install gems for all projects."
-task :install => "all:install"
+task install: "all:install"
 
 desc "Generate documentation for the Rails framework"
-if ENV['EDGE']
-  Rails::API::EdgeTask.new('rdoc')
+if ENV["EDGE"]
+  Rails::API::EdgeTask.new("rdoc")
 else
-  Rails::API::StableTask.new('rdoc')
+  Rails::API::StableTask.new("rdoc")
 end
 
-desc 'Bump all versions to match RAILS_VERSION'
-task :update_versions => "all:update_versions"
+desc "Bump all versions to match RAILS_VERSION"
+task update_versions: "all:update_versions"
 
 # We have a webhook configured in GitHub that gets invoked after pushes.
 # This hook triggers the following tasks:
@@ -61,10 +62,10 @@ task :update_versions => "all:update_versions"
 #   * if there's a new stable tag, generates and publishes stable docs
 #
 # Everything is automated and you do NOT need to run this task normally.
-desc 'Publishes docs, run this AFTER a new stable tag has been pushed'
+desc "Publishes docs, run this AFTER a new stable tag has been pushed"
 task :publish_docs do
-  Net::HTTP.new('api.rubyonrails.org', 8080).start do |http|
-    request  = Net::HTTP::Post.new('/rails-master-hook')
+  Net::HTTP.new("api.rubyonrails.org", 8080).start do |http|
+    request  = Net::HTTP::Post.new("/rails-master-hook")
     response = http.request(request)
     puts response.body
   end
diff --git a/actioncable/CHANGELOG.md b/actioncable/CHANGELOG.md
index a767857607..38bf842b14 100644
--- a/actioncable/CHANGELOG.md
+++ b/actioncable/CHANGELOG.md
@@ -1,2 +1,34 @@
+## Rails 5.2.0.beta2 (November 28, 2017) ##
 
-Please check [5-0-stable](https://github.com/rails/rails/blob/5-0-stable/actioncable/CHANGELOG.md) for previous changes.
+*   No changes.
+
+
+## Rails 5.2.0.beta1 (November 27, 2017) ##
+
+*   Removed deprecated evented redis adapter.
+
+    *Rafael Mendonça França*
+
+*   Support redis-rb 4.0.
+
+    *Jeremy Daer*
+
+*   Hash long stream identifiers when using PostgreSQL adapter.
+
+    PostgreSQL has a limit on identifiers length (63 chars, [docs](https://www.postgresql.org/docs/current/static/sql-syntax-lexical.html#SQL-SYNTAX-IDENTIFIERS)).
+    Provided fix minifies identifiers longer than 63 chars by hashing them with SHA1.
+
+    Fixes #28751.
+
+    *Vladimir Dementyev*
+
+*   Action Cable's `redis` adapter allows for other common redis-rb options (`host`, `port`, `db`, `password`) in cable.yml.
+
+    Previously, it accepts only a [redis:// url](https://www.iana.org/assignments/uri-schemes/prov/redis) as an option.
+    While we can add all of these options to the `url` itself, it is not explicitly documented. This alternative setup
+    is shown as the first example in the [Redis rubygem](https://github.com/redis/redis-rb#getting-started), which
+    makes this set of options as sensible as using just the `url`.
+
+    *Marc Rendl Ignacio*
+
+Please check [5-1-stable](https://github.com/rails/rails/blob/5-1-stable/actioncable/CHANGELOG.md) for previous changes.
diff --git a/actioncable/MIT-LICENSE b/actioncable/MIT-LICENSE
index 27a17cf41b..a42759f024 100644
--- a/actioncable/MIT-LICENSE
+++ b/actioncable/MIT-LICENSE
@@ -1,4 +1,4 @@
-Copyright (c) 2015-2016 Basecamp, LLC
+Copyright (c) 2015-2018 Basecamp, LLC
 
 Permission is hereby granted, free of charge, to any person obtaining
 a copy of this software and associated documentation files (the
diff --git a/actioncable/README.md b/actioncable/README.md
index 58d23d2834..a05ef1dd20 100644
--- a/actioncable/README.md
+++ b/actioncable/README.md
@@ -51,10 +51,10 @@ module ApplicationCable
       self.current_user = find_verified_user
     end
 
-    protected
+    private
       def find_verified_user
-        if current_user = User.find_by(id: cookies.signed[:user_id])
-          current_user
+        if verified_user = User.find_by(id: cookies.encrypted[:user_id])
+          verified_user
         else
           reject_unauthorized_connection
         end
@@ -167,7 +167,7 @@ App.cable.subscriptions.create "AppearanceChannel",
   buttonSelector = "[data-behavior~=appear_away]"
 
   install: ->
-    $(document).on "page:change.appearance", =>
+    $(document).on "turbolinks:load.appearance", =>
       @appear()
 
     $(document).on "click.appearance", buttonSelector, =>
@@ -299,21 +299,257 @@ The rebroadcast will be received by all connected clients, _including_ the clien
 
 See the [rails/actioncable-examples](https://github.com/rails/actioncable-examples) repository for a full example of how to setup Action Cable in a Rails app, and how to add channels.
 
-## Download and installation
+## Configuration
 
-The latest version of Action Cable can be installed with RubyGems:
+Action Cable has three required configurations: a subscription adapter, allowed request origins, and the cable server URL (which can optionally be set on the client side).
 
-    $ gem install actioncable
+### Redis
+
+By default, `ActionCable::Server::Base` will look for a configuration file in `Rails.root.join('config/cable.yml')`.
+This file must specify an adapter and a URL for each Rails environment. It may use the following format:
+
+```yaml
+production: &production
+  adapter: redis
+  url: redis://10.10.3.153:6381
+development: &development
+  adapter: redis
+  url: redis://localhost:6379
+test: *development
+```
+
+You can also change the location of the Action Cable config file in a Rails initializer with something like:
+
+```ruby
+Rails.application.paths.add "config/cable", with: "somewhere/else/cable.yml"
+```
+
+### Allowed Request Origins
+
+Action Cable will only accept requests from specific origins.
+
+By default, only an origin matching the cable server itself will be permitted.
+Additional origins can be specified using strings or regular expressions, provided in an array.
+
+```ruby
+Rails.application.config.action_cable.allowed_request_origins = ['http://rubyonrails.com', /http:\/\/ruby.*/]
+```
+
+When running in the development environment, this defaults to "http://localhost:3000".
+
+To disable protection and allow requests from any origin:
+
+```ruby
+Rails.application.config.action_cable.disable_request_forgery_protection = true
+```
+
+To disable automatic access for same-origin requests, and strictly allow
+only the configured origins:
+
+```ruby
+Rails.application.config.action_cable.allow_same_origin_as_host = false
+```
+
+### Consumer Configuration
+
+Once you have decided how to run your cable server (see below), you must provide the server URL (or path) to your client-side setup.
+There are two ways you can do this.
+
+The first is to simply pass it in when creating your consumer. For a standalone server,
+this would be something like: `App.cable = ActionCable.createConsumer("ws://example.com:28080")`, and for an in-app server,
+something like: `App.cable = ActionCable.createConsumer("/cable")`.
+
+The second option is to pass the server URL through the `action_cable_meta_tag` in your layout.
+This uses a URL or path typically set via `config.action_cable.url` in the environment configuration files, or defaults to "/cable".
+
+This method is especially useful if your WebSocket URL might change between environments. If you host your production server via https, you will need to use the wss scheme
+for your Action Cable server, but development might remain http and use the ws scheme. You might use localhost in development and your
+domain in production.
+
+In any case, to vary the WebSocket URL between environments, add the following configuration to each environment:
+
+```ruby
+config.action_cable.url = "ws://example.com:28080"
+```
+
+Then add the following line to your layout before your JavaScript tag:
+
+```erb
+<%= action_cable_meta_tag %>
+```
+
+And finally, create your consumer like so:
+
+```coffeescript
+App.cable = ActionCable.createConsumer()
+```
+
+### Other Configurations
+
+The other common option to configure is the log tags applied to the per-connection logger. Here's an example that uses the user account id if available, else "no-account" while tagging:
+
+```ruby
+config.action_cable.log_tags = [
+  -> request { request.env['user_account_id'] || "no-account" },
+  :action_cable,
+  -> request { request.uuid }
+]
+```
+
+For a full list of all configuration options, see the `ActionCable::Server::Configuration` class.
+
+Also note that your server must provide at least the same number of database connections as you have workers. The default worker pool is set to 4, so that means you have to make at least that available. You can change that in `config/database.yml` through the `pool` attribute.
+
+
+## Running the cable server
+
+### Standalone
+The cable server(s) is separated from your normal application server. It's still a Rack application, but it is its own Rack
+application. The recommended basic setup is as follows:
+
+```ruby
+# cable/config.ru
+require_relative '../config/environment'
+Rails.application.eager_load!
+
+run ActionCable.server
+```
+
+Then you start the server using a binstub in bin/cable ala:
+```sh
+#!/bin/bash
+bundle exec puma -p 28080 cable/config.ru
+```
+
+The above will start a cable server on port 28080.
+
+### In app
+
+If you are using a server that supports the [Rack socket hijacking API](http://www.rubydoc.info/github/rack/rack/file/SPEC#Hijacking), Action Cable can run alongside your Rails application. For example, to listen for WebSocket requests on `/websocket`, specify that path to `config.action_cable.mount_path`:
+
+```ruby
+# config/application.rb
+class Application < Rails::Application
+  config.action_cable.mount_path = '/websocket'
+end
+```
+
+For every instance of your server you create and for every worker your server spawns, you will also have a new instance of Action Cable, but the use of Redis keeps messages synced across connections.
+
+### Notes
+
+Beware that currently, the cable server will _not_ auto-reload any changes in the framework. As we've discussed, long-running cable connections mean long-running objects. We don't yet have a way of reloading the classes of those objects in a safe manner. So when you change your channels, or the model your channels use, you must restart the cable server.
+
+We'll get all this abstracted properly when the framework is integrated into Rails.
+
+The WebSocket server doesn't have access to the session, but it has access to the cookies. This can be used when you need to handle authentication. You can see one way of doing that with Devise in this [article](http://www.rubytutorial.io/actioncable-devise-authentication).
+
+## Dependencies
+
+Action Cable provides a subscription adapter interface to process its pubsub internals. By default, asynchronous, inline, PostgreSQL, and Redis adapters are included. The default adapter in new Rails applications is the asynchronous (`async`) adapter. To create your own adapter, you can look at `ActionCable::SubscriptionAdapter::Base` for all methods that must be implemented, and any of the adapters included within Action Cable as example implementations.
+
+The Ruby side of things is built on top of [websocket-driver](https://github.com/faye/websocket-driver-ruby), [nio4r](https://github.com/celluloid/nio4r), and [concurrent-ruby](https://github.com/ruby-concurrency/concurrent-ruby).
+
+
+## Deployment
+
+Action Cable is powered by a combination of WebSockets and threads. All of the
+connection management is handled internally by utilizing Ruby's native thread
+support, which means you can use all your regular Rails models with no problems
+as long as you haven't committed any thread-safety sins.
+
+The Action Cable server does _not_ need to be a multi-threaded application server.
+This is because Action Cable uses the [Rack socket hijacking API](http://www.rubydoc.info/github/rack/rack/file/SPEC#Hijacking)
+to take over control of connections from the application server. Action Cable
+then manages connections internally, in a multithreaded manner, regardless of
+whether the application server is multi-threaded or not. So Action Cable works
+with all the popular application servers -- Unicorn, Puma and Passenger.
+
+Action Cable does not work with WEBrick, because WEBrick does not support the
+Rack socket hijacking API.
+
+## Frontend assets
+
+Action Cable's frontend assets are distributed through two channels: the
+official gem and npm package, both titled `actioncable`.
+
+### Gem usage
+
+Through the `actioncable` gem, Action Cable's frontend assets are
+available through the Rails Asset Pipeline. Create a `cable.js` or
+`cable.coffee` file (this is automatically done for you with Rails
+generators), and then simply require the assets:
+
+In JavaScript...
+
+```javascript
+//= require action_cable
+```
+
+... and in CoffeeScript:
+
+```coffeescript
+#= require action_cable
+```
+
+### npm usage
+
+In addition to being available through the `actioncable` gem, Action Cable's
+frontend JS assets are also bundled in an officially supported npm module,
+intended for usage in standalone frontend applications that communicate with a
+Rails application. A common use case for this could be if you have a decoupled
+frontend application written in React, Ember.js, etc. and want to add real-time
+WebSocket functionality.
+
+### Installation
+
+```
+npm install actioncable --save
+```
+
+### Usage
+
+The `ActionCable` constant is available as a `require`-able module, so
+you only have to require the package to gain access to the API that is
+provided.
+
+In JavaScript...
+
+```javascript
+ActionCable = require('actioncable')
+
+var cable = ActionCable.createConsumer('wss://RAILS-API-PATH.com/cable')
+
+cable.subscriptions.create('AppearanceChannel', {
+  // normal channel code goes here...
+});
+```
+
+and in CoffeeScript...
+
+```coffeescript
+ActionCable = require('actioncable')
+
+cable = ActionCable.createConsumer('wss://RAILS-API-PATH.com/cable')
+
+cable.subscriptions.create 'AppearanceChannel',
+    # normal channel code goes here...
+```
+
+## Download and Installation
+
+The latest version of Action Cable can be installed with [RubyGems](#gem-usage),
+or with [npm](#npm-usage).
 
 Source code can be downloaded as part of the Rails project on GitHub
 
-*   https://github.com/rails/rails/tree/master/actioncable
+* https://github.com/rails/rails/tree/master/actioncable
 
 ## License
 
 Action Cable is released under the MIT license:
 
-* http://www.opensource.org/licenses/MIT
+* https://opensource.org/licenses/MIT
 
 
 ## Support
@@ -322,7 +558,7 @@ API documentation is at:
 
 * http://api.rubyonrails.org
 
-Bug reports can be filed for the Ruby on Rails project here:
+Bug reports for the Ruby on Rails project can be filed here:
 
 * https://github.com/rails/rails/issues
 
diff --git a/actioncable/Rakefile b/actioncable/Rakefile
index a72142deb5..226d171104 100644
--- a/actioncable/Rakefile
+++ b/actioncable/Rakefile
@@ -1,17 +1,17 @@
-require 'rake/testtask'
-require 'pathname'
-require 'action_cable'
-require 'blade'
+# frozen_string_literal: true
 
-dir = File.dirname(__FILE__)
+require "rake/testtask"
+require "pathname"
+require "open3"
+require "action_cable"
 
-task :default => :test
+task default: :test
 
-task :package => "assets:compile"
+task package: %w( assets:compile assets:verify )
 
 Rake::TestTask.new do |t|
   t.libs << "test"
-  t.test_files = Dir.glob("#{dir}/test/**/*_test.rb")
+  t.test_files = Dir.glob("#{__dir__}/test/**/*_test.rb")
   t.warning = true
   t.verbose = true
   t.ruby_opts = ["--dev"] if defined?(JRUBY_VERSION)
@@ -20,12 +20,13 @@ end
 namespace :test do
   task :isolated do
     Dir.glob("test/**/*_test.rb").all? do |file|
-      sh(Gem.ruby, '-w', '-Ilib:test', file)
-    end or raise "Failures"
+      sh(Gem.ruby, "-w", "-Ilib:test", file)
+    end || raise("Failures")
   end
 
   task :integration do
-    if ENV['CI']
+    require "blade"
+    if ENV["CI"]
       Blade.start(interface: :ci)
     else
       Blade.start(interface: :runner)
@@ -36,6 +37,40 @@ end
 namespace :assets do
   desc "Compile Action Cable assets"
   task :compile do
+    require "blade"
+    require "sprockets"
+    require "sprockets/export"
     Blade.build
   end
+
+  desc "Verify compiled Action Cable assets"
+  task :verify do
+    file = "lib/assets/compiled/action_cable.js"
+    pathname = Pathname.new("#{__dir__}/#{file}")
+
+    print "[verify] #{file} exists "
+    if pathname.exist?
+      puts "[OK]"
+    else
+      $stderr.puts "[FAIL]"
+      fail
+    end
+
+    print "[verify] #{file} is a UMD module "
+    if pathname.read =~ /module\.exports.*define\.amd/m
+      puts "[OK]"
+    else
+      $stderr.puts "[FAIL]"
+      fail
+    end
+
+    print "[verify] #{__dir__} can be required as a module "
+    _, stderr, status = Open3.capture3("node", "--print", "window = {}; require('#{__dir__}');")
+    if status.success?
+      puts "[OK]"
+    else
+      $stderr.puts "[FAIL]\n#{stderr}"
+      fail
+    end
+  end
 end
diff --git a/actioncable/actioncable.gemspec b/actioncable/actioncable.gemspec
index c65ff7871f..b5b98f1a6b 100644
--- a/actioncable/actioncable.gemspec
+++ b/actioncable/actioncable.gemspec
@@ -1,25 +1,32 @@
-version = File.read(File.expand_path('../../RAILS_VERSION', __FILE__)).strip
+# frozen_string_literal: true
+
+version = File.read(File.expand_path("../RAILS_VERSION", __dir__)).strip
 
 Gem::Specification.new do |s|
   s.platform    = Gem::Platform::RUBY
-  s.name        = 'actioncable'
+  s.name        = "actioncable"
   s.version     = version
-  s.summary     = 'WebSocket framework for Rails.'
-  s.description = 'Structure many real-time application concerns into channels over a single WebSocket connection.'
+  s.summary     = "WebSocket framework for Rails."
+  s.description = "Structure many real-time application concerns into channels over a single WebSocket connection."
+
+  s.required_ruby_version = ">= 2.2.2"
 
-  s.required_ruby_version = '>= 2.2.2'
+  s.license = "MIT"
 
-  s.license = 'MIT'
+  s.author   = ["Pratik Naik", "David Heinemeier Hansson"]
+  s.email    = ["pratiknaik@gmail.com", "david@loudthinking.com"]
+  s.homepage = "http://rubyonrails.org"
 
-  s.author   = ['Pratik Naik', 'David Heinemeier Hansson']
-  s.email    = ['pratiknaik@gmail.com', 'david@loudthinking.com']
-  s.homepage = 'http://rubyonrails.org'
+  s.files        = Dir["CHANGELOG.md", "MIT-LICENSE", "README.md", "lib/**/*"]
+  s.require_path = "lib"
 
-  s.files        = Dir['CHANGELOG.md', 'MIT-LICENSE', 'README.md', 'lib/**/*']
-  s.require_path = 'lib'
+  s.metadata = {
+    "source_code_uri" => "https://github.com/rails/rails/tree/v#{version}/actioncable",
+    "changelog_uri"   => "https://github.com/rails/rails/blob/v#{version}/actioncable/CHANGELOG.md"
+  }
 
-  s.add_dependency 'actionpack', version
+  s.add_dependency "actionpack", version
 
-  s.add_dependency 'nio4r',            '~> 1.2'
-  s.add_dependency 'websocket-driver', '~> 0.6.1'
+  s.add_dependency "nio4r",            "~> 2.0"
+  s.add_dependency "websocket-driver", "~> 0.6.1"
 end
diff --git a/actioncable/app/assets/javascripts/action_cable/connection.coffee b/actioncable/app/assets/javascripts/action_cable/connection.coffee
index 29ad676290..7fd68cad2f 100644
--- a/actioncable/app/assets/javascripts/action_cable/connection.coffee
+++ b/actioncable/app/assets/javascripts/action_cable/connection.coffee
@@ -23,7 +23,7 @@ class ActionCable.Connection
   open: =>
     if @isActive()
       ActionCable.log("Attempted to open WebSocket, but existing socket is #{@getState()}")
-      throw new Error("Existing connection must be closed before opening")
+      false
     else
       ActionCable.log("Opening WebSocket, current state is #{@getState()}, subprotocols: #{protocols}")
       @uninstallEventHandlers() if @webSocket?
diff --git a/actioncable/bin/test b/actioncable/bin/test
new file mode 100755
index 0000000000..c53377cc97
--- /dev/null
+++ b/actioncable/bin/test
@@ -0,0 +1,5 @@
+#!/usr/bin/env ruby
+# frozen_string_literal: true
+
+COMPONENT_ROOT = File.expand_path("..", __dir__)
+require_relative "../../tools/test"
diff --git a/actioncable/lib/action_cable.rb b/actioncable/lib/action_cable.rb
index b6d2842867..e7456e3c1b 100644
--- a/actioncable/lib/action_cable.rb
+++ b/actioncable/lib/action_cable.rb
@@ -1,5 +1,7 @@
+# frozen_string_literal: true
+
 #--
-# Copyright (c) 2015-2016 Basecamp, LLC
+# Copyright (c) 2015-2018 Basecamp, LLC
 #
 # Permission is hereby granted, free of charge, to any person obtaining
 # a copy of this software and associated documentation files (the
@@ -21,21 +23,21 @@
 # WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 #++
 
-require 'active_support'
-require 'active_support/rails'
-require 'action_cable/version'
+require "active_support"
+require "active_support/rails"
+require "action_cable/version"
 
 module ActionCable
   extend ActiveSupport::Autoload
 
   INTERNAL = {
     message_types: {
-      welcome: 'welcome'.freeze,
-      ping: 'ping'.freeze,
-      confirmation: 'confirm_subscription'.freeze,
-      rejection: 'reject_subscription'.freeze
+      welcome: "welcome".freeze,
+      ping: "ping".freeze,
+      confirmation: "confirm_subscription".freeze,
+      rejection: "reject_subscription".freeze
     },
-    default_mount_path: '/cable'.freeze,
+    default_mount_path: "/cable".freeze,
     protocols: ["actioncable-v1-json".freeze, "actioncable-unsupported".freeze].freeze
   }
 
diff --git a/actioncable/lib/action_cable/channel.rb b/actioncable/lib/action_cable/channel.rb
index 7ae262ce5f..d2f6fbbbc7 100644
--- a/actioncable/lib/action_cable/channel.rb
+++ b/actioncable/lib/action_cable/channel.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActionCable
   module Channel
     extend ActiveSupport::Autoload
diff --git a/actioncable/lib/action_cable/channel/base.rb b/actioncable/lib/action_cable/channel/base.rb
index 845b747fc5..c5ad749bfe 100644
--- a/actioncable/lib/action_cable/channel/base.rb
+++ b/actioncable/lib/action_cable/channel/base.rb
@@ -1,4 +1,6 @@
-require 'set'
+# frozen_string_literal: true
+
+require "set"
 
 module ActionCable
   module Channel
@@ -122,16 +124,16 @@ module ActionCable
           end
         end
 
-        protected
+        private
           # action_methods are cached and there is sometimes need to refresh
           # them. ::clear_action_methods! allows you to do that, so next time
           # you run action_methods, they will be recalculated.
-          def clear_action_methods!
+          def clear_action_methods! # :doc:
             @action_methods = nil
           end
 
           # Refresh the cached action_methods when a new action_method is added.
-          def method_added(name)
+          def method_added(name) # :doc:
             super
             clear_action_methods!
           end
@@ -144,13 +146,14 @@ module ActionCable
 
         # When a channel is streaming via pubsub, we want to delay the confirmation
         # transmission until pubsub subscription is confirmed.
-        @defer_subscription_confirmation = false
+        #
+        # The counter starts at 1 because it's awaiting a call to #subscribe_to_channel
+        @defer_subscription_confirmation_counter = Concurrent::AtomicFixnum.new(1)
 
         @reject_subscription = nil
         @subscription_confirmation_sent = nil
 
         delegate_connection_identifiers
-        subscribe_to_channel
       end
 
       # Extract the action name from the passed data and process it via the channel. The process will ensure
@@ -169,6 +172,17 @@ module ActionCable
         end
       end
 
+      # This method is called after subscription has been added to the connection
+      # and confirms or rejects the subscription.
+      def subscribe_to_channel
+        run_callbacks :subscribe do
+          subscribed
+        end
+
+        reject_subscription if subscription_rejected?
+        ensure_confirmation_sent
+      end
+
       # Called by the cable connection when it's cut, so the channel has a chance to cleanup with callbacks.
       # This method is not intended to be called directly by the user. Instead, overwrite the #unsubscribed callback.
       def unsubscribe_from_channel # :nodoc:
@@ -177,24 +191,25 @@ module ActionCable
         end
       end
 
-
-      protected
+      private
         # Called once a consumer has become a subscriber of the channel. Usually the place to setup any streams
         # you want this channel to be sending to the subscriber.
-        def subscribed
+        def subscribed # :doc:
           # Override in subclasses
         end
 
         # Called once a consumer has cut its cable connection. Can be used for cleaning up connections or marking
         # users as offline or the like.
-        def unsubscribed
+        def unsubscribed # :doc:
           # Override in subclasses
         end
 
         # Transmit a hash of data to the subscriber. The hash will automatically be wrapped in a JSON envelope with
         # the proper channel identifier marked as the recipient.
-        def transmit(data, via: nil)
-          logger.info "#{self.class.name} transmitting #{data.inspect.truncate(300)}".tap { |m| m << " (via #{via})" if via }
+        def transmit(data, via: nil) # :doc:
+          status = "#{self.class.name} transmitting #{data.inspect.truncate(300)}"
+          status += " (via #{via})" if via
+          logger.debug(status)
 
           payload = { channel_class: self.class.name, data: data, via: via }
           ActiveSupport::Notifications.instrument("transmit.action_cable", payload) do
@@ -202,27 +217,32 @@ module ActionCable
           end
         end
 
-        def defer_subscription_confirmation!
-          @defer_subscription_confirmation = true
+        def ensure_confirmation_sent # :doc:
+          return if subscription_rejected?
+          @defer_subscription_confirmation_counter.decrement
+          transmit_subscription_confirmation unless defer_subscription_confirmation?
         end
 
-        def defer_subscription_confirmation?
-          @defer_subscription_confirmation
+        def defer_subscription_confirmation! # :doc:
+          @defer_subscription_confirmation_counter.increment
         end
 
-        def subscription_confirmation_sent?
+        def defer_subscription_confirmation? # :doc:
+          @defer_subscription_confirmation_counter.value > 0
+        end
+
+        def subscription_confirmation_sent? # :doc:
           @subscription_confirmation_sent
         end
 
-        def reject
+        def reject # :doc:
           @reject_subscription = true
         end
 
-        def subscription_rejected?
+        def subscription_rejected? # :doc:
           @reject_subscription
         end
 
-      private
         def delegate_connection_identifiers
           connection.identifiers.each do |identifier|
             define_singleton_method(identifier) do
@@ -231,24 +251,12 @@ module ActionCable
           end
         end
 
-        def subscribe_to_channel
-          run_callbacks :subscribe do
-            subscribed
-          end
-
-          if subscription_rejected?
-            reject_subscription
-          else
-            transmit_subscription_confirmation unless defer_subscription_confirmation?
-          end
-        end
-
         def extract_action(data)
-          (data['action'].presence || :receive).to_sym
+          (data["action"].presence || :receive).to_sym
         end
 
         def processable_action?(action)
-          self.class.action_methods.include?(action.to_s)
+          self.class.action_methods.include?(action.to_s) unless subscription_rejected?
         end
 
         def dispatch_action(action, data)
@@ -262,8 +270,8 @@ module ActionCable
         end
 
         def action_signature(action, data)
-          "#{self.class.name}##{action}".tap do |signature|
-            if (arguments = data.except('action')).any?
+          "#{self.class.name}##{action}".dup.tap do |signature|
+            if (arguments = data.except("action")).any?
               signature << "(#{arguments.inspect})"
             end
           end
diff --git a/actioncable/lib/action_cable/channel/broadcasting.rb b/actioncable/lib/action_cable/channel/broadcasting.rb
index afc23d7d1a..acc791817b 100644
--- a/actioncable/lib/action_cable/channel/broadcasting.rb
+++ b/actioncable/lib/action_cable/channel/broadcasting.rb
@@ -1,4 +1,6 @@
-require 'active_support/core_ext/object/to_param'
+# frozen_string_literal: true
+
+require "active_support/core_ext/object/to_param"
 
 module ActionCable
   module Channel
@@ -16,7 +18,7 @@ module ActionCable
         def broadcasting_for(model) #:nodoc:
           case
           when model.is_a?(Array)
-            model.map { |m| broadcasting_for(m) }.join(':')
+            model.map { |m| broadcasting_for(m) }.join(":")
           when model.respond_to?(:to_gid_param)
             model.to_gid_param
           else
diff --git a/actioncable/lib/action_cable/channel/callbacks.rb b/actioncable/lib/action_cable/channel/callbacks.rb
index 295d750e86..4223c0d996 100644
--- a/actioncable/lib/action_cable/channel/callbacks.rb
+++ b/actioncable/lib/action_cable/channel/callbacks.rb
@@ -1,4 +1,6 @@
-require 'active_support/callbacks'
+# frozen_string_literal: true
+
+require "active_support/callbacks"
 
 module ActionCable
   module Channel
diff --git a/actioncable/lib/action_cable/channel/naming.rb b/actioncable/lib/action_cable/channel/naming.rb
index 8e1b2a4af0..03a5dcd3a0 100644
--- a/actioncable/lib/action_cable/channel/naming.rb
+++ b/actioncable/lib/action_cable/channel/naming.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActionCable
   module Channel
     module Naming
@@ -12,7 +14,7 @@ module ActionCable
         #   Chats::AppearancesChannel.channel_name # => 'chats:appearances'
         #   FooChats::BarAppearancesChannel.channel_name # => 'foo_chats:bar_appearances'
         def channel_name
-          @channel_name ||= name.sub(/Channel$/, '').gsub('::',':').underscore
+          @channel_name ||= name.sub(/Channel$/, "").gsub("::", ":").underscore
         end
       end
 
diff --git a/actioncable/lib/action_cable/channel/periodic_timers.rb b/actioncable/lib/action_cable/channel/periodic_timers.rb
index dab604440f..830b3efa3c 100644
--- a/actioncable/lib/action_cable/channel/periodic_timers.rb
+++ b/actioncable/lib/action_cable/channel/periodic_timers.rb
@@ -1,11 +1,12 @@
+# frozen_string_literal: true
+
 module ActionCable
   module Channel
     module PeriodicTimers
       extend ActiveSupport::Concern
 
       included do
-        class_attribute :periodic_timers, instance_reader: false
-        self.periodic_timers = []
+        class_attribute :periodic_timers, instance_reader: false, default: []
 
         after_subscribe   :start_periodic_timers
         after_unsubscribe :stop_periodic_timers
@@ -30,7 +31,7 @@ module ActionCable
         def periodically(callback_or_method_name = nil, every:, &block)
           callback =
             if block_given?
-              raise ArgumentError, 'Pass a block or provide a callback arg, not both' if callback_or_method_name
+              raise ArgumentError, "Pass a block or provide a callback arg, not both" if callback_or_method_name
               block
             else
               case callback_or_method_name
@@ -64,9 +65,7 @@ module ActionCable
 
         def start_periodic_timer(callback, every:)
           connection.server.event_loop.timer every do
-            connection.worker_pool.async_invoke connection do
-              instance_exec(&callback)
-            end
+            connection.worker_pool.async_exec self, connection: connection, &callback
           end
         end
 
diff --git a/actioncable/lib/action_cable/channel/streams.rb b/actioncable/lib/action_cable/channel/streams.rb
index 561750d713..81c2c38064 100644
--- a/actioncable/lib/action_cable/channel/streams.rb
+++ b/actioncable/lib/action_cable/channel/streams.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActionCable
   module Channel
     # Streams allow channels to route broadcastings to the subscriber. A broadcasting is, as discussed elsewhere, a pubsub queue where any data
@@ -69,8 +71,8 @@ module ActionCable
 
       # Start streaming from the named <tt>broadcasting</tt> pubsub queue. Optionally, you can pass a <tt>callback</tt> that'll be used
       # instead of the default of just transmitting the updates straight to the subscriber.
-      # Pass `coder: ActiveSupport::JSON` to decode messages as JSON before passing to the callback.
-      # Defaults to `coder: nil` which does no decoding, passes raw messages.
+      # Pass <tt>coder: ActiveSupport::JSON</tt> to decode messages as JSON before passing to the callback.
+      # Defaults to <tt>coder: nil</tt> which does no decoding, passes raw messages.
       def stream_from(broadcasting, callback = nil, coder: nil, &block)
         broadcasting = String(broadcasting)
 
@@ -84,7 +86,7 @@ module ActionCable
 
         connection.server.event_loop.post do
           pubsub.subscribe(broadcasting, handler, lambda do
-            transmit_subscription_confirmation
+            ensure_confirmation_sent
             logger.info "#{self.class.name} is streaming from #{broadcasting}"
           end)
         end
@@ -94,8 +96,8 @@ module ActionCable
       # <tt>callback</tt> that'll be used instead of the default of just transmitting the updates straight
       # to the subscriber.
       #
-      # Pass `coder: ActiveSupport::JSON` to decode messages as JSON before passing to the callback.
-      # Defaults to `coder: nil` which does no decoding, passes raw messages.
+      # Pass <tt>coder: ActiveSupport::JSON</tt> to decode messages as JSON before passing to the callback.
+      # Defaults to <tt>coder: nil</tt> which does no decoding, passes raw messages.
       def stream_for(model, callback = nil, coder: nil, &block)
         stream_from(broadcasting_for([ channel_name, model ]), callback || block, coder: coder)
       end
diff --git a/actioncable/lib/action_cable/connection.rb b/actioncable/lib/action_cable/connection.rb
index 5f813cf8e0..804b89a707 100644
--- a/actioncable/lib/action_cable/connection.rb
+++ b/actioncable/lib/action_cable/connection.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActionCable
   module Connection
     extend ActiveSupport::Autoload
@@ -8,8 +10,6 @@ module ActionCable
       autoload :ClientSocket
       autoload :Identification
       autoload :InternalChannel
-      autoload :FayeClientSocket
-      autoload :FayeEventLoop
       autoload :MessageBuffer
       autoload :Stream
       autoload :StreamEventLoop
diff --git a/actioncable/lib/action_cable/connection/authorization.rb b/actioncable/lib/action_cable/connection/authorization.rb
index 070a70e4e2..a22179d988 100644
--- a/actioncable/lib/action_cable/connection/authorization.rb
+++ b/actioncable/lib/action_cable/connection/authorization.rb
@@ -1,13 +1,15 @@
+# frozen_string_literal: true
+
 module ActionCable
   module Connection
     module Authorization
       class UnauthorizedError < StandardError; end
 
-      private
-        def reject_unauthorized_connection
-          logger.error "An unauthorized connection attempt was rejected"
-          raise UnauthorizedError
-        end
+      # Closes the \WebSocket connection if it is open and returns a 404 "File not Found" response.
+      def reject_unauthorized_connection
+        logger.error "An unauthorized connection attempt was rejected"
+        raise UnauthorizedError
+      end
     end
   end
-end
\ No newline at end of file
+end
diff --git a/actioncable/lib/action_cable/connection/base.rb b/actioncable/lib/action_cable/connection/base.rb
index 75c1299e36..84053db9fd 100644
--- a/actioncable/lib/action_cable/connection/base.rb
+++ b/actioncable/lib/action_cable/connection/base.rb
@@ -1,4 +1,6 @@
-require 'action_dispatch'
+# frozen_string_literal: true
+
+require "action_dispatch"
 
 module ActionCable
   module Connection
@@ -22,13 +24,10 @@ module ActionCable
     #         # Any cleanup work needed when the cable connection is cut.
     #       end
     #
-    #       protected
+    #       private
     #         def find_verified_user
-    #           if current_user = User.find_by_identity cookies.signed[:identity_id]
-    #             current_user
-    #           else
+    #           User.find_by_identity(cookies.encrypted[:identity_id]) ||
     #             reject_unauthorized_connection
-    #           end
     #         end
     #     end
     #   end
@@ -57,7 +56,7 @@ module ActionCable
         @worker_pool = server.worker_pool
         @logger = new_tagged_logger
 
-        @websocket      = ActionCable::Connection::WebSocket.new(env, self, event_loop, server.config.client_socket_class)
+        @websocket      = ActionCable::Connection::WebSocket.new(env, self, event_loop)
         @subscriptions  = ActionCable::Connection::Subscriptions.new(self)
         @message_buffer = ActionCable::Connection::MessageBuffer.new(self)
 
@@ -105,14 +104,14 @@ module ActionCable
         worker_pool.async_invoke(self, method, *arguments)
       end
 
-      # Return a basic hash of statistics for the connection keyed with `identifier`, `started_at`, and `subscriptions`.
+      # Return a basic hash of statistics for the connection keyed with <tt>identifier</tt>, <tt>started_at</tt>, <tt>subscriptions</tt>, and <tt>request_id</tt>.
       # This can be returned by a health check against the connection.
       def statistics
         {
           identifier: connection_identifier,
           started_at: @started_at,
           subscriptions: subscriptions.identifiers,
-          request_id: @env['action_dispatch.request_id']
+          request_id: @env["action_dispatch.request_id"]
         }
       end
 
@@ -129,16 +128,23 @@ module ActionCable
       end
 
       def on_error(message) # :nodoc:
-        # ignore
+        # log errors to make diagnosing socket errors easier
+        logger.error "WebSocket error occurred: #{message}"
       end
 
       def on_close(reason, code) # :nodoc:
         send_async :handle_close
       end
 
+      # TODO Change this to private once we've dropped Ruby 2.2 support.
+      # Workaround for Ruby 2.2 "private attribute?" warning.
       protected
+        attr_reader :websocket
+        attr_reader :message_buffer
+
+      private
         # The request that initiated the WebSocket connection is available here. This gives access to the environment, cookies, etc.
-        def request
+        def request # :doc:
           @request ||= begin
             environment = Rails.application.env_config.merge(env) if defined?(Rails.application) && Rails.application
             ActionDispatch::Request.new(environment || env)
@@ -146,14 +152,10 @@ module ActionCable
         end
 
         # The cookies of the request that initiated the WebSocket connection. Useful for performing authorization checks.
-        def cookies
+        def cookies # :doc:
           request.cookie_jar
         end
 
-        attr_reader :websocket
-        attr_reader :message_buffer
-
-      private
         def encode(cable_message)
           @coder.encode cable_message
         end
@@ -195,7 +197,10 @@ module ActionCable
         def allow_request_origin?
           return true if server.config.disable_request_forgery_protection
 
-          if Array(server.config.allowed_request_origins).any? { |allowed_origin|  allowed_origin === env['HTTP_ORIGIN'] }
+          proto = Rack::Request.new(env).ssl? ? "https" : "http"
+          if server.config.allow_same_origin_as_host && env["HTTP_ORIGIN"] == "#{proto}://#{env['HTTP_HOST']}"
+            true
+          elsif Array(server.config.allowed_request_origins).any? { |allowed_origin|  allowed_origin === env["HTTP_ORIGIN"] }
             true
           else
             logger.error("Request origin not allowed: #{env['HTTP_ORIGIN']}")
@@ -213,7 +218,7 @@ module ActionCable
 
           logger.error invalid_request_message
           logger.info finished_request_message
-          [ 404, { 'Content-Type' => 'text/plain' }, [ 'Page not found' ] ]
+          [ 404, { "Content-Type" => "text/plain" }, [ "Page not found" ] ]
         end
 
         # Tags are declared in the server but computed in the connection. This allows us per-connection tailored tags.
@@ -226,7 +231,7 @@ module ActionCable
           'Started %s "%s"%s for %s at %s' % [
             request.request_method,
             request.filtered_path,
-            websocket.possible? ? ' [WebSocket]' : '[non-WebSocket]',
+            websocket.possible? ? " [WebSocket]" : "[non-WebSocket]",
             request.ip,
             Time.now.to_s ]
         end
@@ -234,19 +239,19 @@ module ActionCable
         def finished_request_message
           'Finished "%s"%s for %s at %s' % [
             request.filtered_path,
-            websocket.possible? ? ' [WebSocket]' : '[non-WebSocket]',
+            websocket.possible? ? " [WebSocket]" : "[non-WebSocket]",
             request.ip,
             Time.now.to_s ]
         end
 
         def invalid_request_message
-          'Failed to upgrade to WebSocket (REQUEST_METHOD: %s, HTTP_CONNECTION: %s, HTTP_UPGRADE: %s)' % [
+          "Failed to upgrade to WebSocket (REQUEST_METHOD: %s, HTTP_CONNECTION: %s, HTTP_UPGRADE: %s)" % [
             env["REQUEST_METHOD"], env["HTTP_CONNECTION"], env["HTTP_UPGRADE"]
           ]
         end
 
         def successful_request_message
-          'Successfully upgraded to WebSocket (REQUEST_METHOD: %s, HTTP_CONNECTION: %s, HTTP_UPGRADE: %s)' % [
+          "Successfully upgraded to WebSocket (REQUEST_METHOD: %s, HTTP_CONNECTION: %s, HTTP_UPGRADE: %s)" % [
             env["REQUEST_METHOD"], env["HTTP_CONNECTION"], env["HTTP_UPGRADE"]
           ]
         end
diff --git a/actioncable/lib/action_cable/connection/client_socket.rb b/actioncable/lib/action_cable/connection/client_socket.rb
index 6f29f32ea9..10289ab55c 100644
--- a/actioncable/lib/action_cable/connection/client_socket.rb
+++ b/actioncable/lib/action_cable/connection/client_socket.rb
@@ -1,4 +1,6 @@
-require 'websocket/driver'
+# frozen_string_literal: true
+
+require "websocket/driver"
 
 module ActionCable
   module Connection
@@ -8,18 +10,18 @@ module ActionCable
     # Copyright (c) 2010-2015 James Coglan
     class ClientSocket # :nodoc:
       def self.determine_url(env)
-        scheme = secure_request?(env) ? 'wss:' : 'ws:'
+        scheme = secure_request?(env) ? "wss:" : "ws:"
         "#{ scheme }//#{ env['HTTP_HOST'] }#{ env['REQUEST_URI'] }"
       end
 
       def self.secure_request?(env)
-        return true if env['HTTPS'] == 'on'
-        return true if env['HTTP_X_FORWARDED_SSL'] == 'on'
-        return true if env['HTTP_X_FORWARDED_SCHEME'] == 'https'
-        return true if env['HTTP_X_FORWARDED_PROTO'] == 'https'
-        return true if env['rack.url_scheme'] == 'https'
+        return true if env["HTTPS"] == "on"
+        return true if env["HTTP_X_FORWARDED_SSL"] == "on"
+        return true if env["HTTP_X_FORWARDED_SCHEME"] == "https"
+        return true if env["HTTP_X_FORWARDED_PROTO"] == "https"
+        return true if env["rack.url_scheme"] == "https"
 
-        return false
+        false
       end
 
       CONNECTING = 0
@@ -37,7 +39,7 @@ module ActionCable
         @url = ClientSocket.determine_url(@env)
 
         @driver = @driver_started = nil
-        @close_params = ['', 1006]
+        @close_params = ["", 1006]
 
         @ready_state = CONNECTING
 
@@ -56,7 +58,7 @@ module ActionCable
         return if @driver.nil? || @driver_started
         @stream.hijack_rack_socket
 
-        if callback = @env['async.callback']
+        if callback = @env["async.callback"]
           callback.call([101, {}, @stream])
         end
 
@@ -78,20 +80,20 @@ module ActionCable
       def transmit(message)
         return false if @ready_state > OPEN
         case message
-          when Numeric then @driver.text(message.to_s)
-          when String  then @driver.text(message)
-          when Array   then @driver.binary(message)
+        when Numeric then @driver.text(message.to_s)
+        when String  then @driver.text(message)
+        when Array   then @driver.binary(message)
           else false
         end
       end
 
       def close(code = nil, reason = nil)
         code   ||= 1000
-        reason ||= ''
+        reason ||= ""
 
-        unless code == 1000 or (code >= 3000 and code <= 4999)
-          raise ArgumentError, "Failed to execute 'close' on WebSocket: " +
-                               "The code must be either 1000, or between 3000 and 4999. " +
+        unless code == 1000 || (code >= 3000 && code <= 4999)
+          raise ArgumentError, "Failed to execute 'close' on WebSocket: " \
+                               "The code must be either 1000, or between 3000 and 4999. " \
                                "#{code} is neither."
         end
 
diff --git a/actioncable/lib/action_cable/connection/faye_client_socket.rb b/actioncable/lib/action_cable/connection/faye_client_socket.rb
deleted file mode 100644
index a4bfe7db17..0000000000
--- a/actioncable/lib/action_cable/connection/faye_client_socket.rb
+++ /dev/null
@@ -1,48 +0,0 @@
-require 'faye/websocket'
-
-module ActionCable
-  module Connection
-    class FayeClientSocket
-      def initialize(env, event_target, stream_event_loop, protocols)
-        @env = env
-        @event_target = event_target
-        @protocols = protocols
-
-        @faye = nil
-      end
-
-      def alive?
-        @faye && @faye.ready_state == Faye::WebSocket::API::OPEN
-      end
-
-      def transmit(data)
-        connect
-        @faye.send data
-      end
-
-      def close
-        @faye && @faye.close
-      end
-
-      def protocol
-        @faye && @faye.protocol
-      end
-
-      def rack_response
-        connect
-        @faye.rack_response
-      end
-
-      private
-        def connect
-          return if @faye
-          @faye = Faye::WebSocket.new(@env, @protocols)
-
-          @faye.on(:open)    { |event| @event_target.on_open }
-          @faye.on(:message) { |event| @event_target.on_message(event.data) }
-          @faye.on(:close)   { |event| @event_target.on_close(event.reason, event.code) }
-          @faye.on(:error)   { |event| @event_target.on_error(event.message) }
-        end
-    end
-  end
-end
diff --git a/actioncable/lib/action_cable/connection/faye_event_loop.rb b/actioncable/lib/action_cable/connection/faye_event_loop.rb
deleted file mode 100644
index 9c44b38bc3..0000000000
--- a/actioncable/lib/action_cable/connection/faye_event_loop.rb
+++ /dev/null
@@ -1,44 +0,0 @@
-require 'thread'
-
-require 'eventmachine'
-EventMachine.epoll  if EventMachine.epoll?
-EventMachine.kqueue if EventMachine.kqueue?
-
-module ActionCable
-  module Connection
-    class FayeEventLoop
-      @@mutex = Mutex.new
-
-      def timer(interval, &block)
-        ensure_reactor_running
-        EMTimer.new(::EM::PeriodicTimer.new(interval, &block))
-      end
-
-      def post(task = nil, &block)
-        task ||= block
-
-        ensure_reactor_running
-        ::EM.next_tick(&task)
-      end
-
-      private
-        def ensure_reactor_running
-          return if EventMachine.reactor_running?
-          @@mutex.synchronize do
-            Thread.new { EventMachine.run } unless EventMachine.reactor_running?
-            Thread.pass until EventMachine.reactor_running?
-          end
-        end
-
-        class EMTimer
-          def initialize(inner)
-            @inner = inner
-          end
-
-          def shutdown
-            @inner.cancel
-          end
-        end
-    end
-  end
-end
diff --git a/actioncable/lib/action_cable/connection/identification.rb b/actioncable/lib/action_cable/connection/identification.rb
index 4a54044aff..4b5f9ca115 100644
--- a/actioncable/lib/action_cable/connection/identification.rb
+++ b/actioncable/lib/action_cable/connection/identification.rb
@@ -1,4 +1,6 @@
-require 'set'
+# frozen_string_literal: true
+
+require "set"
 
 module ActionCable
   module Connection
@@ -6,8 +8,7 @@ module ActionCable
       extend ActiveSupport::Concern
 
       included do
-        class_attribute :identifiers
-        self.identifiers = Set.new
+        class_attribute :identifiers, default: Set.new
       end
 
       class_methods do
diff --git a/actioncable/lib/action_cable/connection/internal_channel.rb b/actioncable/lib/action_cable/connection/internal_channel.rb
index f70d52f99b..f03904137b 100644
--- a/actioncable/lib/action_cable/connection/internal_channel.rb
+++ b/actioncable/lib/action_cable/connection/internal_channel.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActionCable
   module Connection
     # Makes it possible for the RemoteConnection to disconnect a specific connection.
@@ -27,8 +29,8 @@ module ActionCable
         end
 
         def process_internal_message(message)
-          case message['type']
-          when 'disconnect'
+          case message["type"]
+          when "disconnect"
             logger.info "Removing connection (#{connection_identifier})"
             websocket.close
           end
diff --git a/actioncable/lib/action_cable/connection/message_buffer.rb b/actioncable/lib/action_cable/connection/message_buffer.rb
index 6a80770cae..f151a47072 100644
--- a/actioncable/lib/action_cable/connection/message_buffer.rb
+++ b/actioncable/lib/action_cable/connection/message_buffer.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActionCable
   module Connection
     # Allows us to buffer messages received from the WebSocket before the Connection has been fully initialized, and is ready to receive them.
@@ -28,6 +30,8 @@ module ActionCable
         receive_buffered_messages
       end
 
+      # TODO Change this to private once we've dropped Ruby 2.2 support.
+      # Workaround for Ruby 2.2 "private attribute?" warning.
       protected
         attr_reader :connection
         attr_reader :buffered_messages
diff --git a/actioncable/lib/action_cable/connection/stream.rb b/actioncable/lib/action_cable/connection/stream.rb
index 0cf59091bc..4873026b71 100644
--- a/actioncable/lib/action_cable/connection/stream.rb
+++ b/actioncable/lib/action_cable/connection/stream.rb
@@ -1,3 +1,7 @@
+# frozen_string_literal: true
+
+require "thread"
+
 module ActionCable
   module Connection
     #--
@@ -8,9 +12,13 @@ module ActionCable
       def initialize(event_loop, socket)
         @event_loop    = event_loop
         @socket_object = socket
-        @stream_send   = socket.env['stream.send']
+        @stream_send   = socket.env["stream.send"]
 
         @rack_hijack_io = nil
+        @write_lock = Mutex.new
+
+        @write_head = nil
+        @write_buffer = Queue.new
       end
 
       def each(&callback)
@@ -27,21 +35,71 @@ module ActionCable
       end
 
       def write(data)
-        return @rack_hijack_io.write(data) if @rack_hijack_io
-        return @stream_send.call(data) if @stream_send
+        if @stream_send
+          return @stream_send.call(data)
+        end
+
+        if @write_lock.try_lock
+          begin
+            if @write_head.nil? && @write_buffer.empty?
+              written = @rack_hijack_io.write_nonblock(data, exception: false)
+
+              case written
+              when :wait_writable
+                # proceed below
+              when data.bytesize
+                return data.bytesize
+              else
+                @write_head = data.byteslice(written, data.bytesize)
+                @event_loop.writes_pending @rack_hijack_io
+
+                return data.bytesize
+              end
+            end
+          ensure
+            @write_lock.unlock
+          end
+        end
+
+        @write_buffer << data
+        @event_loop.writes_pending @rack_hijack_io
+
+        data.bytesize
       rescue EOFError, Errno::ECONNRESET
         @socket_object.client_gone
       end
 
+      def flush_write_buffer
+        @write_lock.synchronize do
+          loop do
+            if @write_head.nil?
+              return true if @write_buffer.empty?
+              @write_head = @write_buffer.pop
+            end
+
+            written = @rack_hijack_io.write_nonblock(@write_head, exception: false)
+            case written
+            when :wait_writable
+              return false
+            when @write_head.bytesize
+              @write_head = nil
+            else
+              @write_head = @write_head.byteslice(written, @write_head.bytesize)
+              return false
+            end
+          end
+        end
+      end
+
       def receive(data)
         @socket_object.parse(data)
       end
 
       def hijack_rack_socket
-        return unless @socket_object.env['rack.hijack']
+        return unless @socket_object.env["rack.hijack"]
 
-        @socket_object.env['rack.hijack'].call
-        @rack_hijack_io = @socket_object.env['rack.hijack_io']
+        @socket_object.env["rack.hijack"].call
+        @rack_hijack_io = @socket_object.env["rack.hijack_io"]
 
         @event_loop.attach(@rack_hijack_io, self)
       end
diff --git a/actioncable/lib/action_cable/connection/stream_event_loop.rb b/actioncable/lib/action_cable/connection/stream_event_loop.rb
index 2abad09c03..d95afc50ba 100644
--- a/actioncable/lib/action_cable/connection/stream_event_loop.rb
+++ b/actioncable/lib/action_cable/connection/stream_event_loop.rb
@@ -1,11 +1,13 @@
-require 'nio'
-require 'thread'
+# frozen_string_literal: true
+
+require "nio"
+require "thread"
 
 module ActionCable
   module Connection
     class StreamEventLoop
       def initialize
-        @nio = @thread = nil
+        @nio = @executor = @thread = nil
         @map = {}
         @stopping = false
         @todo = Queue.new
@@ -20,13 +22,14 @@ module ActionCable
       def post(task = nil, &block)
         task ||= block
 
-        Concurrent.global_io_executor << task
+        spawn
+        @executor << task
       end
 
       def attach(io, stream)
         @todo << lambda do
-          @map[io] = stream
-          @nio.register(io, :r)
+          @map[io] = @nio.register(io, :r)
+          @map[io].value = stream
         end
         wakeup
       end
@@ -35,6 +38,16 @@ module ActionCable
         @todo << lambda do
           @nio.deregister io
           @map.delete io
+          io.close
+        end
+        wakeup
+      end
+
+      def writes_pending(io)
+        @todo << lambda do
+          if monitor = @map[io]
+            monitor.interests = :rw
+          end
         end
         wakeup
       end
@@ -52,6 +65,13 @@ module ActionCable
             return if @thread && @thread.status
 
             @nio ||= NIO::Selector.new
+
+            @executor ||= Concurrent::ThreadPoolExecutor.new(
+              min_threads: 1,
+              max_threads: 10,
+              max_queue: 0,
+            )
+
             @thread = Thread.new { run }
 
             return true
@@ -77,12 +97,25 @@ module ActionCable
 
             monitors.each do |monitor|
               io = monitor.io
-              stream = @map[io]
+              stream = monitor.value
 
               begin
-                stream.receive io.read_nonblock(4096)
-              rescue IO::WaitReadable
-                next
+                if monitor.writable?
+                  if stream.flush_write_buffer
+                    monitor.interests = :r
+                  end
+                  next unless monitor.readable?
+                end
+
+                incoming = io.read_nonblock(4096, exception: false)
+                case incoming
+                when :wait_readable
+                  next
+                when nil
+                  stream.close
+                else
+                  stream.receive incoming
+                end
               rescue
                 # We expect one of EOFError or Errno::ECONNRESET in
                 # normal operation (when the client goes away). But if
diff --git a/actioncable/lib/action_cable/connection/subscriptions.rb b/actioncable/lib/action_cable/connection/subscriptions.rb
index 6051818bfb..bb8d64e27a 100644
--- a/actioncable/lib/action_cable/connection/subscriptions.rb
+++ b/actioncable/lib/action_cable/connection/subscriptions.rb
@@ -1,4 +1,6 @@
-require 'active_support/core_ext/hash/indifferent_access'
+# frozen_string_literal: true
+
+require "active_support/core_ext/hash/indifferent_access"
 
 module ActionCable
   module Connection
@@ -11,25 +13,29 @@ module ActionCable
       end
 
       def execute_command(data)
-        case data['command']
-        when 'subscribe'   then add data
-        when 'unsubscribe' then remove data
-        when 'message'     then perform_action data
+        case data["command"]
+        when "subscribe"   then add data
+        when "unsubscribe" then remove data
+        when "message"     then perform_action data
         else
           logger.error "Received unrecognized command in #{data.inspect}"
         end
       rescue Exception => e
-        logger.error "Could not execute command from #{data.inspect}) [#{e.class} - #{e.message}]: #{e.backtrace.first(5).join(" | ")}"
+        logger.error "Could not execute command from (#{data.inspect}) [#{e.class} - #{e.message}]: #{e.backtrace.first(5).join(" | ")}"
       end
 
       def add(data)
-        id_key = data['identifier']
+        id_key = data["identifier"]
         id_options = ActiveSupport::JSON.decode(id_key).with_indifferent_access
 
+        return if subscriptions.key?(id_key)
+
         subscription_klass = id_options[:channel].safe_constantize
 
         if subscription_klass && ActionCable::Channel::Base >= subscription_klass
-          subscriptions[id_key] ||= subscription_klass.new(connection, id_key, id_options)
+          subscription = subscription_klass.new(connection, id_key, id_options)
+          subscriptions[id_key] = subscription
+          subscription.subscribe_to_channel
         else
           logger.error "Subscription class not found: #{id_options[:channel].inspect}"
         end
@@ -37,7 +43,7 @@ module ActionCable
 
       def remove(data)
         logger.info "Unsubscribing from channel: #{data['identifier']}"
-        remove_subscription subscriptions[data['identifier']]
+        remove_subscription find(data)
       end
 
       def remove_subscription(subscription)
@@ -46,7 +52,7 @@ module ActionCable
       end
 
       def perform_action(data)
-        find(data).perform_action ActiveSupport::JSON.decode(data['data'])
+        find(data).perform_action ActiveSupport::JSON.decode(data["data"])
       end
 
       def identifiers
@@ -57,6 +63,8 @@ module ActionCable
         subscriptions.each { |id, channel| remove_subscription(channel) }
       end
 
+      # TODO Change this to private once we've dropped Ruby 2.2 support.
+      # Workaround for Ruby 2.2 "private attribute?" warning.
       protected
         attr_reader :connection, :subscriptions
 
@@ -64,7 +72,7 @@ module ActionCable
         delegate :logger, to: :connection
 
         def find(data)
-          if subscription = subscriptions[data['identifier']]
+          if subscription = subscriptions[data["identifier"]]
             subscription
           else
             raise "Unable to find subscription with identifier: #{data['identifier']}"
diff --git a/actioncable/lib/action_cable/connection/tagged_logger_proxy.rb b/actioncable/lib/action_cable/connection/tagged_logger_proxy.rb
index 41afa9680a..85831806a9 100644
--- a/actioncable/lib/action_cable/connection/tagged_logger_proxy.rb
+++ b/actioncable/lib/action_cable/connection/tagged_logger_proxy.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActionCable
   module Connection
     # Allows the use of per-connection tags against the server logger. This wouldn't work using the traditional
@@ -31,8 +33,8 @@ module ActionCable
         end
       end
 
-      protected
-        def log(type, message)
+      private
+        def log(type, message) # :doc:
           tag(@logger) { @logger.send type, message }
         end
     end
diff --git a/actioncable/lib/action_cable/connection/web_socket.rb b/actioncable/lib/action_cable/connection/web_socket.rb
index 11f28c37e8..81233ace34 100644
--- a/actioncable/lib/action_cable/connection/web_socket.rb
+++ b/actioncable/lib/action_cable/connection/web_socket.rb
@@ -1,11 +1,13 @@
-require 'websocket/driver'
+# frozen_string_literal: true
+
+require "websocket/driver"
 
 module ActionCable
   module Connection
     # Wrap the real socket to minimize the externally-presented API
-    class WebSocket
-      def initialize(env, event_target, event_loop, client_socket_class, protocols: ActionCable::INTERNAL[:protocols])
-        @websocket = ::WebSocket::Driver.websocket?(env) ? client_socket_class.new(env, event_target, event_loop, protocols) : nil
+    class WebSocket # :nodoc:
+      def initialize(env, event_target, event_loop, protocols: ActionCable::INTERNAL[:protocols])
+        @websocket = ::WebSocket::Driver.websocket?(env) ? ClientSocket.new(env, event_target, event_loop, protocols) : nil
       end
 
       def possible?
@@ -32,6 +34,8 @@ module ActionCable
         websocket.rack_response
       end
 
+      # TODO Change this to private once we've dropped Ruby 2.2 support.
+      # Workaround for Ruby 2.2 "private attribute?" warning.
       protected
         attr_reader :websocket
     end
diff --git a/actioncable/lib/action_cable/engine.rb b/actioncable/lib/action_cable/engine.rb
index 34f9952c71..53cbb597cd 100644
--- a/actioncable/lib/action_cable/engine.rb
+++ b/actioncable/lib/action_cable/engine.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require "rails"
 require "action_cable"
 require "action_cable/helpers/action_cable_helper"
@@ -31,10 +33,10 @@ module ActionCable
           self.cable = Rails.application.config_for(config_path).with_indifferent_access
         end
 
-        previous_connection_class = self.connection_class
-        self.connection_class = -> { 'ApplicationCable::Connection'.safe_constantize || previous_connection_class.call }
+        previous_connection_class = connection_class
+        self.connection_class = -> { "ApplicationCable::Connection".safe_constantize || previous_connection_class.call }
 
-        options.each { |k,v| send("#{k}=", v) }
+        options.each { |k, v| send("#{k}=", v) }
       end
     end
 
diff --git a/actioncable/lib/action_cable/gem_version.rb b/actioncable/lib/action_cable/gem_version.rb
index 8ba0230d47..d72ba18acd 100644
--- a/actioncable/lib/action_cable/gem_version.rb
+++ b/actioncable/lib/action_cable/gem_version.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActionCable
   # Returns the version of the currently loaded Action Cable as a <tt>Gem::Version</tt>.
   def self.gem_version
@@ -6,9 +8,9 @@ module ActionCable
 
   module VERSION
     MAJOR = 5
-    MINOR = 1
+    MINOR = 2
     TINY  = 0
-    PRE   = "alpha"
+    PRE   = "beta2"
 
     STRING = [MAJOR, MINOR, TINY, PRE].compact.join(".")
   end
diff --git a/actioncable/lib/action_cable/helpers/action_cable_helper.rb b/actioncable/lib/action_cable/helpers/action_cable_helper.rb
index 2081a37db6..df16c02e83 100644
--- a/actioncable/lib/action_cable/helpers/action_cable_helper.rb
+++ b/actioncable/lib/action_cable/helpers/action_cable_helper.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActionCable
   module Helpers
     module ActionCableHelper
@@ -6,7 +8,7 @@ module ActionCable
       #
       #   <head>
       #     <%= action_cable_meta_tag %>
-      #     <%= javascript_include_tag 'application', 'data-turbolinks-track' => true %>
+      #     <%= javascript_include_tag 'application', 'data-turbolinks-track' => 'reload' %>
       #   </head>
       #
       # This is then used by Action Cable to determine the URL of your WebSocket server.
diff --git a/actioncable/lib/action_cable/remote_connections.rb b/actioncable/lib/action_cable/remote_connections.rb
index a528024427..283400d9e7 100644
--- a/actioncable/lib/action_cable/remote_connections.rb
+++ b/actioncable/lib/action_cable/remote_connections.rb
@@ -1,3 +1,7 @@
+# frozen_string_literal: true
+
+require "active_support/core_ext/module/redefine_method"
+
 module ActionCable
   # If you need to disconnect a given connection, you can go through the
   # RemoteConnections. You can find the connections you're looking for by
@@ -41,20 +45,21 @@ module ActionCable
 
         # Uses the internal channel to disconnect the connection.
         def disconnect
-          server.broadcast internal_channel, type: 'disconnect'
+          server.broadcast internal_channel, type: "disconnect"
         end
 
         # Returns all the identifiers that were applied to this connection.
-        def identifiers
+        redefine_method :identifiers do
           server.connection_identifiers
         end
 
-        private
+        protected
           attr_reader :server
 
+        private
           def set_identifier_instance_vars(ids)
             raise InvalidIdentifiersError unless valid_identifiers?(ids)
-            ids.each { |k,v| instance_variable_set("@#{k}", v) }
+            ids.each { |k, v| instance_variable_set("@#{k}", v) }
           end
 
           def valid_identifiers?(ids)
diff --git a/actioncable/lib/action_cable/server.rb b/actioncable/lib/action_cable/server.rb
index bd6a3826a3..8d485a44f6 100644
--- a/actioncable/lib/action_cable/server.rb
+++ b/actioncable/lib/action_cable/server.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActionCable
   module Server
     extend ActiveSupport::Autoload
@@ -9,7 +11,7 @@ module ActionCable
       autoload :Configuration
 
       autoload :Worker
-      autoload :ActiveRecordConnectionManagement, 'action_cable/server/worker/active_record_connection_management'
+      autoload :ActiveRecordConnectionManagement, "action_cable/server/worker/active_record_connection_management"
     end
   end
 end
diff --git a/actioncable/lib/action_cable/server/base.rb b/actioncable/lib/action_cable/server/base.rb
index 0ad1e408a9..1ee03f6dfc 100644
--- a/actioncable/lib/action_cable/server/base.rb
+++ b/actioncable/lib/action_cable/server/base.rb
@@ -1,4 +1,6 @@
-require 'monitor'
+# frozen_string_literal: true
+
+require "monitor"
 
 module ActionCable
   module Server
@@ -10,7 +12,7 @@ module ActionCable
       include ActionCable::Server::Broadcasting
       include ActionCable::Server::Connections
 
-      cattr_accessor(:config, instance_accessor: true) { ActionCable::Server::Configuration.new }
+      cattr_accessor :config, instance_accessor: true, default: ActionCable::Server::Configuration.new
 
       def self.logger; config.logger; end
       delegate :logger, to: :config
@@ -28,7 +30,7 @@ module ActionCable
         config.connection_class.call.new(self, env).process
       end
 
-      # Disconnect all the connections identified by `identifiers` on this server or any others via RemoteConnections.
+      # Disconnect all the connections identified by +identifiers+ on this server or any others via RemoteConnections.
       def disconnect(identifiers)
         remote_connections.where(identifiers).disconnect
       end
@@ -37,9 +39,13 @@ module ActionCable
         connections.each(&:close)
 
         @mutex.synchronize do
-          worker_pool.halt if @worker_pool
-
+          # Shutdown the worker pool
+          @worker_pool.halt if @worker_pool
           @worker_pool = nil
+
+          # Shutdown the pub/sub adapter
+          @pubsub.shutdown if @pubsub
+          @pubsub = nil
         end
       end
 
@@ -49,12 +55,12 @@ module ActionCable
       end
 
       def event_loop
-        @event_loop || @mutex.synchronize { @event_loop ||= config.event_loop_class.new }
+        @event_loop || @mutex.synchronize { @event_loop ||= ActionCable::Connection::StreamEventLoop.new }
       end
 
       # The worker pool is where we run connection callbacks and channel actions. We do as little as possible on the server's main thread.
       # The worker pool is an executor service that's backed by a pool of threads working from a task queue. The thread pool size maxes out
-      # at 4 worker threads by default. Tune the size yourself with `config.action_cable.worker_pool_size`.
+      # at 4 worker threads by default. Tune the size yourself with <tt>config.action_cable.worker_pool_size</tt>.
       #
       # Using Active Record, Redis, etc within your channel actions means you'll get a separate connection from each thread in the worker pool.
       # Plan your deployment accordingly: 5 servers each running 5 Puma workers each running an 8-thread worker pool means at least 200 database
diff --git a/actioncable/lib/action_cable/server/broadcasting.rb b/actioncable/lib/action_cable/server/broadcasting.rb
index 8f93564113..bc54d784b3 100644
--- a/actioncable/lib/action_cable/server/broadcasting.rb
+++ b/actioncable/lib/action_cable/server/broadcasting.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActionCable
   module Server
     # Broadcasting is how other parts of your application can send messages to a channel's subscribers. As explained in Channel, most of the time, these
@@ -38,9 +40,13 @@ module ActionCable
           end
 
           def broadcast(message)
-            server.logger.info "[ActionCable] Broadcasting to #{broadcasting}: #{message.inspect}"
-            encoded = coder ? coder.encode(message) : message
-            server.pubsub.broadcast broadcasting, encoded
+            server.logger.debug "[ActionCable] Broadcasting to #{broadcasting}: #{message.inspect}"
+
+            payload = { broadcasting: broadcasting, message: message, coder: coder }
+            ActiveSupport::Notifications.instrument("broadcast.action_cable", payload) do
+              encoded = coder ? coder.encode(message) : message
+              server.pubsub.broadcast broadcasting, encoded
+            end
           end
         end
     end
diff --git a/actioncable/lib/action_cable/server/configuration.rb b/actioncable/lib/action_cable/server/configuration.rb
index ada1ac22cc..26209537df 100644
--- a/actioncable/lib/action_cable/server/configuration.rb
+++ b/actioncable/lib/action_cable/server/configuration.rb
@@ -1,11 +1,13 @@
+# frozen_string_literal: true
+
 module ActionCable
   module Server
     # An instance of this configuration object is available via ActionCable.server.config, which allows you to tweak Action Cable configuration
     # in a Rails config initializer.
     class Configuration
       attr_accessor :logger, :log_tags
-      attr_accessor :use_faye, :connection_class, :worker_pool_size
-      attr_accessor :disable_request_forgery_protection, :allowed_request_origins
+      attr_accessor :connection_class, :worker_pool_size
+      attr_accessor :disable_request_forgery_protection, :allowed_request_origins, :allow_same_origin_as_host
       attr_accessor :cable, :url, :mount_path
 
       def initialize
@@ -15,42 +17,40 @@ module ActionCable
         @worker_pool_size = 4
 
         @disable_request_forgery_protection = false
+        @allow_same_origin_as_host = true
       end
 
       # Returns constant of subscription adapter specified in config/cable.yml.
       # If the adapter cannot be found, this will default to the Redis adapter.
       # Also makes sure proper dependencies are required.
       def pubsub_adapter
-        adapter = (cable.fetch('adapter') { 'redis' })
+        adapter = (cable.fetch("adapter") { "redis" })
+
+        # Require the adapter itself and give useful feedback about
+        #   1. Missing adapter gems and
+        #   2. Adapter gems' missing dependencies.
         path_to_adapter = "action_cable/subscription_adapter/#{adapter}"
         begin
           require path_to_adapter
-        rescue Gem::LoadError => e
-          raise Gem::LoadError, "Specified '#{adapter}' for Action Cable pubsub adapter, but the gem is not loaded. Add `gem '#{e.name}'` to your Gemfile (and ensure its version is at the minimum required by Action Cable)."
         rescue LoadError => e
-          raise LoadError, "Could not load '#{path_to_adapter}'. Make sure that the adapter in config/cable.yml is valid. If you use an adapter other than 'postgresql' or 'redis' add the necessary adapter gem to the Gemfile.", e.backtrace
+          # We couldn't require the adapter itself. Raise an exception that
+          # points out config typos and missing gems.
+          if e.path == path_to_adapter
+            # We can assume that a non-builtin adapter was specified, so it's
+            # either misspelled or missing from Gemfile.
+            raise e.class, "Could not load the '#{adapter}' Action Cable pubsub adapter. Ensure that the adapter is spelled correctly in config/cable.yml and that you've added the necessary adapter gem to your Gemfile.", e.backtrace
+
+          # Bubbled up from the adapter require. Prefix the exception message
+          # with some guidance about how to address it and reraise.
+          else
+            raise e.class, "Error loading the '#{adapter}' Action Cable pubsub adapter. Missing a gem it depends on? #{e.message}", e.backtrace
+          end
         end
 
         adapter = adapter.camelize
-        adapter = 'PostgreSQL' if adapter == 'Postgresql'
+        adapter = "PostgreSQL" if adapter == "Postgresql"
         "ActionCable::SubscriptionAdapter::#{adapter}".constantize
       end
-
-      def event_loop_class
-        if use_faye
-          ActionCable::Connection::FayeEventLoop
-        else
-          ActionCable::Connection::StreamEventLoop
-        end
-      end
-
-      def client_socket_class
-        if use_faye
-          ActionCable::Connection::FayeClientSocket
-        else
-          ActionCable::Connection::ClientSocket
-        end
-      end
     end
   end
 end
diff --git a/actioncable/lib/action_cable/server/connections.rb b/actioncable/lib/action_cable/server/connections.rb
index 5e61b4e335..39557d63a7 100644
--- a/actioncable/lib/action_cable/server/connections.rb
+++ b/actioncable/lib/action_cable/server/connections.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActionCable
   module Server
     # Collection class for all the connections that have been established on this specific server. Remember, usually you'll run many Action Cable servers, so
diff --git a/actioncable/lib/action_cable/server/worker.rb b/actioncable/lib/action_cable/server/worker.rb
index a638ff72e7..c69cc4ac31 100644
--- a/actioncable/lib/action_cable/server/worker.rb
+++ b/actioncable/lib/action_cable/server/worker.rb
@@ -1,6 +1,8 @@
-require 'active_support/callbacks'
-require 'active_support/core_ext/module/attribute_accessors_per_thread'
-require 'concurrent'
+# frozen_string_literal: true
+
+require "active_support/callbacks"
+require "active_support/core_ext/module/attribute_accessors_per_thread"
+require "concurrent"
 
 module ActionCable
   module Server
@@ -25,7 +27,7 @@ module ActionCable
       # Stop processing work: any work that has not already started
       # running will be discarded from the queue
       def halt
-        @executor.kill
+        @executor.shutdown
       end
 
       def stopping?
@@ -42,16 +44,20 @@ module ActionCable
         self.connection = nil
       end
 
-      def async_invoke(receiver, method, *args, connection: receiver)
+      def async_exec(receiver, *args, connection:, &block)
+        async_invoke receiver, :instance_exec, *args, connection: connection, &block
+      end
+
+      def async_invoke(receiver, method, *args, connection: receiver, &block)
         @executor.post do
-          invoke(receiver, method, *args, connection: connection)
+          invoke(receiver, method, *args, connection: connection, &block)
         end
       end
 
-      def invoke(receiver, method, *args, connection:)
+      def invoke(receiver, method, *args, connection:, &block)
         work(connection) do
           begin
-            receiver.send method, *args
+            receiver.send method, *args, &block
           rescue Exception => e
             logger.error "There was an exception - #{e.class}(#{e.message})"
             logger.error e.backtrace.join("\n")
diff --git a/actioncable/lib/action_cable/server/worker/active_record_connection_management.rb b/actioncable/lib/action_cable/server/worker/active_record_connection_management.rb
index c1e4aa8103..2e378d4bf3 100644
--- a/actioncable/lib/action_cable/server/worker/active_record_connection_management.rb
+++ b/actioncable/lib/action_cable/server/worker/active_record_connection_management.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActionCable
   module Server
     class Worker
diff --git a/actioncable/lib/action_cable/subscription_adapter.rb b/actioncable/lib/action_cable/subscription_adapter.rb
index 72e62f3daf..bcece8d33b 100644
--- a/actioncable/lib/action_cable/subscription_adapter.rb
+++ b/actioncable/lib/action_cable/subscription_adapter.rb
@@ -1,8 +1,11 @@
+# frozen_string_literal: true
+
 module ActionCable
   module SubscriptionAdapter
     extend ActiveSupport::Autoload
 
     autoload :Base
     autoload :SubscriberMap
+    autoload :ChannelPrefix
   end
 end
diff --git a/actioncable/lib/action_cable/subscription_adapter/async.rb b/actioncable/lib/action_cable/subscription_adapter/async.rb
index 10b3ac8cd8..c9930299c7 100644
--- a/actioncable/lib/action_cable/subscription_adapter/async.rb
+++ b/actioncable/lib/action_cable/subscription_adapter/async.rb
@@ -1,4 +1,6 @@
-require 'action_cable/subscription_adapter/inline'
+# frozen_string_literal: true
+
+require "action_cable/subscription_adapter/inline"
 
 module ActionCable
   module SubscriptionAdapter
diff --git a/actioncable/lib/action_cable/subscription_adapter/base.rb b/actioncable/lib/action_cable/subscription_adapter/base.rb
index 796db5ffa3..34077707fd 100644
--- a/actioncable/lib/action_cable/subscription_adapter/base.rb
+++ b/actioncable/lib/action_cable/subscription_adapter/base.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActionCable
   module SubscriptionAdapter
     class Base
diff --git a/actioncable/lib/action_cable/subscription_adapter/channel_prefix.rb b/actioncable/lib/action_cable/subscription_adapter/channel_prefix.rb
new file mode 100644
index 0000000000..df0aa040f5
--- /dev/null
+++ b/actioncable/lib/action_cable/subscription_adapter/channel_prefix.rb
@@ -0,0 +1,28 @@
+# frozen_string_literal: true
+
+module ActionCable
+  module SubscriptionAdapter
+    module ChannelPrefix # :nodoc:
+      def broadcast(channel, payload)
+        channel = channel_with_prefix(channel)
+        super
+      end
+
+      def subscribe(channel, callback, success_callback = nil)
+        channel = channel_with_prefix(channel)
+        super
+      end
+
+      def unsubscribe(channel, callback)
+        channel = channel_with_prefix(channel)
+        super
+      end
+
+      private
+        # Returns the channel name, including channel_prefix specified in cable.yml
+        def channel_with_prefix(channel)
+          [@server.config.cable[:channel_prefix], channel].compact.join(":")
+        end
+    end
+  end
+end
diff --git a/actioncable/lib/action_cable/subscription_adapter/evented_redis.rb b/actioncable/lib/action_cable/subscription_adapter/evented_redis.rb
deleted file mode 100644
index 4735a4bfa8..0000000000
--- a/actioncable/lib/action_cable/subscription_adapter/evented_redis.rb
+++ /dev/null
@@ -1,79 +0,0 @@
-require 'thread'
-
-gem 'em-hiredis', '~> 0.3.0'
-gem 'redis', '~> 3.0'
-require 'em-hiredis'
-require 'redis'
-
-EventMachine.epoll  if EventMachine.epoll?
-EventMachine.kqueue if EventMachine.kqueue?
-
-module ActionCable
-  module SubscriptionAdapter
-    class EventedRedis < Base # :nodoc:
-      @@mutex = Mutex.new
-
-      # Overwrite this factory method for EventMachine Redis connections if you want to use a different Redis connection library than EM::Hiredis.
-      # This is needed, for example, when using Makara proxies for distributed Redis.
-      cattr_accessor(:em_redis_connector) { ->(config) { EM::Hiredis.connect(config[:url]) } }
-
-      # Overwrite this factory method for Redis connections if you want to use a different Redis connection library than Redis.
-      # This is needed, for example, when using Makara proxies for distributed Redis.
-      cattr_accessor(:redis_connector) { ->(config) { ::Redis.new(url: config[:url]) } }
-
-      def initialize(*)
-        super
-        @redis_connection_for_broadcasts = @redis_connection_for_subscriptions = nil
-      end
-
-      def broadcast(channel, payload)
-        redis_connection_for_broadcasts.publish(channel, payload)
-      end
-
-      def subscribe(channel, message_callback, success_callback = nil)
-        redis_connection_for_subscriptions.pubsub.subscribe(channel, &message_callback).tap do |result|
-          result.callback { |reply| success_callback.call } if success_callback
-        end
-      end
-
-      def unsubscribe(channel, message_callback)
-        redis_connection_for_subscriptions.pubsub.unsubscribe_proc(channel, message_callback)
-      end
-
-      def shutdown
-        redis_connection_for_subscriptions.pubsub.close_connection
-        @redis_connection_for_subscriptions = nil
-      end
-
-      private
-        def redis_connection_for_subscriptions
-          ensure_reactor_running
-          @redis_connection_for_subscriptions || @server.mutex.synchronize do
-            @redis_connection_for_subscriptions ||= self.class.em_redis_connector.call(@server.config.cable).tap do |redis|
-              redis.on(:reconnect_failed) do
-                @logger.error "[ActionCable] Redis reconnect failed."
-              end
-
-              redis.on(:failed) do
-                @logger.error "[ActionCable] Redis connection has failed."
-              end
-            end
-          end
-        end
-
-        def redis_connection_for_broadcasts
-          @redis_connection_for_broadcasts || @server.mutex.synchronize do
-            @redis_connection_for_broadcasts ||= self.class.redis_connector.call(@server.config.cable)
-          end
-        end
-
-        def ensure_reactor_running
-          return if EventMachine.reactor_running?
-          @@mutex.synchronize do
-            Thread.new { EventMachine.run } unless EventMachine.reactor_running?
-            Thread.pass until EventMachine.reactor_running?
-          end
-        end
-    end
-  end
-end
diff --git a/actioncable/lib/action_cable/subscription_adapter/inline.rb b/actioncable/lib/action_cable/subscription_adapter/inline.rb
index 81357faead..d2c85c1c8d 100644
--- a/actioncable/lib/action_cable/subscription_adapter/inline.rb
+++ b/actioncable/lib/action_cable/subscription_adapter/inline.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActionCable
   module SubscriptionAdapter
     class Inline < Base # :nodoc:
diff --git a/actioncable/lib/action_cable/subscription_adapter/postgresql.rb b/actioncable/lib/action_cable/subscription_adapter/postgresql.rb
index 66c7852f6e..a9c0949950 100644
--- a/actioncable/lib/action_cable/subscription_adapter/postgresql.rb
+++ b/actioncable/lib/action_cable/subscription_adapter/postgresql.rb
@@ -1,6 +1,9 @@
-gem 'pg', '~> 0.18'
-require 'pg'
-require 'thread'
+# frozen_string_literal: true
+
+gem "pg", "~> 0.18"
+require "pg"
+require "thread"
+require "digest/sha1"
 
 module ActionCable
   module SubscriptionAdapter
@@ -12,16 +15,16 @@ module ActionCable
 
       def broadcast(channel, payload)
         with_connection do |pg_conn|
-          pg_conn.exec("NOTIFY #{pg_conn.escape_identifier(channel)}, '#{pg_conn.escape_string(payload)}'")
+          pg_conn.exec("NOTIFY #{pg_conn.escape_identifier(channel_identifier(channel))}, '#{pg_conn.escape_string(payload)}'")
         end
       end
 
       def subscribe(channel, callback, success_callback = nil)
-        listener.add_subscriber(channel, callback, success_callback)
+        listener.add_subscriber(channel_identifier(channel), callback, success_callback)
       end
 
       def unsubscribe(channel, callback)
-        listener.remove_subscriber(channel, callback)
+        listener.remove_subscriber(channel_identifier(channel), callback)
       end
 
       def shutdown
@@ -33,7 +36,7 @@ module ActionCable
           pg_conn = ar_conn.raw_connection
 
           unless pg_conn.is_a?(PG::Connection)
-            raise 'ActiveRecord database must be Postgres in order to use the Postgres ActionCable storage adapter'
+            raise "The Active Record database must be PostgreSQL in order to use the PostgreSQL Action Cable storage adapter"
           end
 
           yield pg_conn
@@ -41,6 +44,10 @@ module ActionCable
       end
 
       private
+        def channel_identifier(channel)
+          channel.size > 63 ? Digest::SHA1.hexdigest(channel) : channel
+        end
+
         def listener
           @listener || @server.mutex.synchronize { @listener ||= Listener.new(self, @server.event_loop) }
         end
diff --git a/actioncable/lib/action_cable/subscription_adapter/redis.rb b/actioncable/lib/action_cable/subscription_adapter/redis.rb
index 65434f7107..c28951608f 100644
--- a/actioncable/lib/action_cable/subscription_adapter/redis.rb
+++ b/actioncable/lib/action_cable/subscription_adapter/redis.rb
@@ -1,14 +1,20 @@
-require 'thread'
+# frozen_string_literal: true
 
-gem 'redis', '~> 3.0'
-require 'redis'
+require "thread"
+
+gem "redis", ">= 3", "< 5"
+require "redis"
 
 module ActionCable
   module SubscriptionAdapter
     class Redis < Base # :nodoc:
-      # Overwrite this factory method for redis connections if you want to use a different Redis library than Redis.
+      prepend ChannelPrefix
+
+      # Overwrite this factory method for Redis connections if you want to use a different Redis library than the redis gem.
       # This is needed, for example, when using Makara proxies for distributed Redis.
-      cattr_accessor(:redis_connector) { ->(config) { ::Redis.new(url: config[:url]) } }
+      cattr_accessor :redis_connector, default: ->(config) do
+        ::Redis.new(config.slice(:url, :host, :port, :db, :password))
+      end
 
       def initialize(*)
         super
@@ -70,9 +76,9 @@ module ActionCable
 
           def listen(conn)
             conn.without_reconnect do
-              original_client = conn.client
+              original_client = conn.respond_to?(:_client) ? conn._client : conn.client
 
-              conn.subscribe('_action_cable_internal') do |on|
+              conn.subscribe("_action_cable_internal") do |on|
                 on.subscribe do |chan, count|
                   @subscription_lock.synchronize do
                     if count == 1
@@ -111,7 +117,7 @@ module ActionCable
               return if @thread.nil?
 
               when_connected do
-                send_command('unsubscribe')
+                send_command("unsubscribe")
                 @raw_client = nil
               end
             end
@@ -123,13 +129,13 @@ module ActionCable
             @subscription_lock.synchronize do
               ensure_listener_running
               @subscribe_callbacks[channel] << on_success
-              when_connected { send_command('subscribe', channel) }
+              when_connected { send_command("subscribe", channel) }
             end
           end
 
           def remove_channel(channel)
             @subscription_lock.synchronize do
-              when_connected { send_command('unsubscribe', channel) }
+              when_connected { send_command("unsubscribe", channel) }
             end
           end
 
diff --git a/actioncable/lib/action_cable/subscription_adapter/subscriber_map.rb b/actioncable/lib/action_cable/subscription_adapter/subscriber_map.rb
index 37eed09793..01cdc2dfa1 100644
--- a/actioncable/lib/action_cable/subscription_adapter/subscriber_map.rb
+++ b/actioncable/lib/action_cable/subscription_adapter/subscriber_map.rb
@@ -1,8 +1,10 @@
+# frozen_string_literal: true
+
 module ActionCable
   module SubscriptionAdapter
     class SubscriberMap
       def initialize
-        @subscribers = Hash.new { |h,k| h[k] = [] }
+        @subscribers = Hash.new { |h, k| h[k] = [] }
         @sync = Mutex.new
       end
 
@@ -32,7 +34,11 @@ module ActionCable
       end
 
       def broadcast(channel, message)
-        list = @sync.synchronize { @subscribers[channel].dup }
+        list = @sync.synchronize do
+          return if !@subscribers.key?(channel)
+          @subscribers[channel].dup
+        end
+
         list.each do |subscriber|
           invoke_callback(subscriber, message)
         end
diff --git a/actioncable/lib/action_cable/version.rb b/actioncable/lib/action_cable/version.rb
index e17877202b..86115c6065 100644
--- a/actioncable/lib/action_cable/version.rb
+++ b/actioncable/lib/action_cable/version.rb
@@ -1,4 +1,6 @@
-require_relative 'gem_version'
+# frozen_string_literal: true
+
+require_relative "gem_version"
 
 module ActionCable
   # Returns the version of the currently loaded Action Cable as a <tt>Gem::Version</tt>
diff --git a/actioncable/lib/rails/generators/channel/USAGE b/actioncable/lib/rails/generators/channel/USAGE
index 6249553c22..dd109fda80 100644
--- a/actioncable/lib/rails/generators/channel/USAGE
+++ b/actioncable/lib/rails/generators/channel/USAGE
@@ -3,7 +3,7 @@ Description:
     Stubs out a new cable channel for the server (in Ruby) and client (in CoffeeScript).
     Pass the channel name, either CamelCased or under_scored, and an optional list of channel actions as arguments.
 
-    Note: Turn on the cable connection in app/assets/javascript/cable.js after generating any channels.
+    Note: Turn on the cable connection in app/assets/javascripts/cable.js after generating any channels.
 
 Example:
 ========
@@ -11,4 +11,4 @@ Example:
 
     creates a Chat channel class and CoffeeScript asset:
         Channel:    app/channels/chat_channel.rb
-        Assets:     app/assets/javascript/channels/chat.coffee
+        Assets:     app/assets/javascripts/channels/chat.coffee
diff --git a/actioncable/lib/rails/generators/channel/channel_generator.rb b/actioncable/lib/rails/generators/channel/channel_generator.rb
index 47232252e3..c3528370c6 100644
--- a/actioncable/lib/rails/generators/channel/channel_generator.rb
+++ b/actioncable/lib/rails/generators/channel/channel_generator.rb
@@ -1,7 +1,9 @@
+# frozen_string_literal: true
+
 module Rails
   module Generators
     class ChannelGenerator < NamedBase
-      source_root File.expand_path("../templates", __FILE__)
+      source_root File.expand_path("templates", __dir__)
 
       argument :actions, type: :array, default: [], banner: "method method"
 
@@ -10,35 +12,35 @@ module Rails
       check_class_collision suffix: "Channel"
 
       def create_channel_file
-        template "channel.rb", File.join('app/channels', class_path, "#{file_name}_channel.rb")
+        template "channel.rb", File.join("app/channels", class_path, "#{file_name}_channel.rb")
 
         if options[:assets]
-          if self.behavior == :invoke
+          if behavior == :invoke
             template "assets/cable.js", "app/assets/javascripts/cable.js"
           end
 
-          js_template "assets/channel", File.join('app/assets/javascripts/channels', class_path, "#{file_name}")
+          js_template "assets/channel", File.join("app/assets/javascripts/channels", class_path, "#{file_name}")
         end
 
         generate_application_cable_files
       end
 
-      protected
+      private
         def file_name
-          @_file_name ||= super.gsub(/_channel/i, '')
+          @_file_name ||= super.gsub(/_channel/i, "")
         end
 
         # FIXME: Change these files to symlinks once RubyGems 2.5.0 is required.
         def generate_application_cable_files
-          return if self.behavior != :invoke
+          return if behavior != :invoke
 
           files = [
-            'application_cable/channel.rb',
-            'application_cable/connection.rb'
+            "application_cable/channel.rb",
+            "application_cable/connection.rb"
           ]
 
           files.each do |name|
-            path = File.join('app/channels/', name)
+            path = File.join("app/channels/", name)
             template(name, path) if !File.exist?(path)
           end
         end
diff --git a/actioncable/lib/rails/generators/channel/templates/application_cable/channel.rb b/actioncable/lib/rails/generators/channel/templates/application_cable/channel.rb
deleted file mode 100644
index 17a85f60f9..0000000000
--- a/actioncable/lib/rails/generators/channel/templates/application_cable/channel.rb
+++ /dev/null
@@ -1,6 +0,0 @@
-# Be sure to restart your server when you modify this file. Action Cable runs in
-# a loop that does not support auto reloading.
-module ApplicationCable
-  class Channel < ActionCable::Channel::Base
-  end
-end
diff --git a/railties/lib/rails/generators/rails/app/templates/app/channels/application_cable/channel.rb b/actioncable/lib/rails/generators/channel/templates/application_cable/channel.rb.tt
index d672697283..d672697283 100644
--- a/railties/lib/rails/generators/rails/app/templates/app/channels/application_cable/channel.rb
+++ b/actioncable/lib/rails/generators/channel/templates/application_cable/channel.rb.tt
diff --git a/actioncable/lib/rails/generators/channel/templates/application_cable/connection.rb b/actioncable/lib/rails/generators/channel/templates/application_cable/connection.rb
deleted file mode 100644
index 93f28c4306..0000000000
--- a/actioncable/lib/rails/generators/channel/templates/application_cable/connection.rb
+++ /dev/null
@@ -1,6 +0,0 @@
-# Be sure to restart your server when you modify this file. Action Cable runs in
-# a loop that does not support auto reloading.
-module ApplicationCable
-  class Connection < ActionCable::Connection::Base
-  end
-end
diff --git a/railties/lib/rails/generators/rails/app/templates/app/channels/application_cable/connection.rb b/actioncable/lib/rails/generators/channel/templates/application_cable/connection.rb.tt
index 0ff5442f47..0ff5442f47 100644
--- a/railties/lib/rails/generators/rails/app/templates/app/channels/application_cable/connection.rb
+++ b/actioncable/lib/rails/generators/channel/templates/application_cable/connection.rb.tt
diff --git a/actioncable/lib/rails/generators/channel/templates/assets/cable.js b/actioncable/lib/rails/generators/channel/templates/assets/cable.js.tt
index 71ee1e66de..739aa5f022 100644
--- a/actioncable/lib/rails/generators/channel/templates/assets/cable.js
+++ b/actioncable/lib/rails/generators/channel/templates/assets/cable.js.tt
@@ -1,5 +1,5 @@
 // Action Cable provides the framework to deal with WebSockets in Rails.
-// You can generate new channels where WebSocket features live using the rails generate channel command.
+// You can generate new channels where WebSocket features live using the `rails generate channel` command.
 //
 //= require action_cable
 //= require_self
diff --git a/actioncable/lib/rails/generators/channel/templates/assets/channel.coffee b/actioncable/lib/rails/generators/channel/templates/assets/channel.coffee.tt
index 5467811aba..5467811aba 100644
--- a/actioncable/lib/rails/generators/channel/templates/assets/channel.coffee
+++ b/actioncable/lib/rails/generators/channel/templates/assets/channel.coffee.tt
diff --git a/actioncable/lib/rails/generators/channel/templates/assets/channel.js b/actioncable/lib/rails/generators/channel/templates/assets/channel.js.tt
index ab0e68b11a..ab0e68b11a 100644
--- a/actioncable/lib/rails/generators/channel/templates/assets/channel.js
+++ b/actioncable/lib/rails/generators/channel/templates/assets/channel.js.tt
diff --git a/actioncable/lib/rails/generators/channel/templates/channel.rb b/actioncable/lib/rails/generators/channel/templates/channel.rb.tt
index 7bff3341c1..4bcfb2be4d 100644
--- a/actioncable/lib/rails/generators/channel/templates/channel.rb
+++ b/actioncable/lib/rails/generators/channel/templates/channel.rb.tt
@@ -1,4 +1,3 @@
-# Be sure to restart your server when you modify this file. Action Cable runs in a loop that does not support auto reloading.
 <% module_namespacing do -%>
 class <%= class_name %>Channel < ApplicationCable::Channel
   def subscribed
diff --git a/actioncable/package.json b/actioncable/package.json
index 37f82fa1ea..8d7f9ff302 100644
--- a/actioncable/package.json
+++ b/actioncable/package.json
@@ -1,6 +1,6 @@
 {
   "name": "actioncable",
-  "version": "5.0.0-rc1",
+  "version": "5.2.0-beta2",
   "description": "WebSocket framework for Ruby on Rails.",
   "main": "lib/assets/compiled/action_cable.js",
   "files": [
diff --git a/actioncable/test/channel/base_test.rb b/actioncable/test/channel/base_test.rb
index daa782eeb3..866bd7c21b 100644
--- a/actioncable/test/channel/base_test.rb
+++ b/actioncable/test/channel/base_test.rb
@@ -1,6 +1,8 @@
-require 'test_helper'
-require 'stubs/test_connection'
-require 'stubs/room'
+# frozen_string_literal: true
+
+require "test_helper"
+require "stubs/test_connection"
+require "stubs/room"
 
 class ActionCable::Channel::BaseTest < ActiveSupport::TestCase
   class ActionCable::Channel::Base
@@ -58,7 +60,7 @@ class ActionCable::Channel::BaseTest < ActiveSupport::TestCase
     end
 
     def get_latest
-      transmit data: 'latest'
+      transmit data: "latest"
     end
 
     def receive
@@ -74,14 +76,16 @@ class ActionCable::Channel::BaseTest < ActiveSupport::TestCase
   setup do
     @user = User.new "lifo"
     @connection = TestConnection.new(@user)
-    @channel = ChatChannel.new @connection, "{id: 1}", { id: 1 }
+    @channel = ChatChannel.new @connection, "{id: 1}", id: 1
   end
 
-  test "should subscribe to a channel on initialize" do
+  test "should subscribe to a channel" do
+    @channel.subscribe_to_channel
     assert_equal 1, @channel.room.id
   end
 
   test "on subscribe callbacks" do
+    @channel.subscribe_to_channel
     assert @channel.subscribed
   end
 
@@ -90,6 +94,8 @@ class ActionCable::Channel::BaseTest < ActiveSupport::TestCase
   end
 
   test "unsubscribing from a channel" do
+    @channel.subscribe_to_channel
+
     assert @channel.room
     assert @channel.subscribed?
 
@@ -104,54 +110,59 @@ class ActionCable::Channel::BaseTest < ActiveSupport::TestCase
   end
 
   test "callable action without any argument" do
-    @channel.perform_action 'action' => :leave
+    @channel.perform_action "action" => :leave
     assert_equal [ :leave ], @channel.last_action
   end
 
   test "callable action with arguments" do
-    data = { 'action' => :speak, 'content' => "Hello World" }
+    data = { "action" => :speak, "content" => "Hello World" }
 
     @channel.perform_action data
     assert_equal [ :speak, data ], @channel.last_action
   end
 
   test "should not dispatch a private method" do
-    @channel.perform_action 'action' => :rm_rf
+    @channel.perform_action "action" => :rm_rf
     assert_nil @channel.last_action
   end
 
   test "should not dispatch a public method defined on Base" do
-    @channel.perform_action 'action' => :kick
+    @channel.perform_action "action" => :kick
     assert_nil @channel.last_action
   end
 
   test "should dispatch a public method defined on Base and redefined on channel" do
-    data = { 'action' => :topic, 'content' => "This is Sparta!" }
+    data = { "action" => :topic, "content" => "This is Sparta!" }
 
     @channel.perform_action data
     assert_equal [ :topic, data ], @channel.last_action
   end
 
   test "should dispatch calling a public method defined in an ancestor" do
-    @channel.perform_action 'action' => :chatters
+    @channel.perform_action "action" => :chatters
     assert_equal [ :chatters ], @channel.last_action
   end
 
   test "should dispatch receive action when perform_action is called with empty action" do
-    data = { 'content' => 'hello' }
+    data = { "content" => "hello" }
     @channel.perform_action data
     assert_equal [ :receive ], @channel.last_action
   end
 
   test "transmitting data" do
-    @channel.perform_action 'action' => :get_latest
+    @channel.perform_action "action" => :get_latest
 
-    expected = { "identifier" => "{id: 1}", "message" => { "data" => "latest" }}
+    expected = { "identifier" => "{id: 1}", "message" => { "data" => "latest" } }
     assert_equal expected, @connection.last_transmission
   end
 
-  test "subscription confirmation" do
+  test "do not send subscription confirmation on initialize" do
+    assert_nil @connection.last_transmission
+  end
+
+  test "subscription confirmation on subscribe_to_channel" do
     expected = { "identifier" => "{id: 1}", "type" => "confirm_subscription" }
+    @channel.subscribe_to_channel
     assert_equal expected, @connection.last_transmission
   end
 
@@ -162,7 +173,7 @@ class ActionCable::Channel::BaseTest < ActiveSupport::TestCase
 
   test "invalid action on Channel" do
     assert_logged("Unable to process ActionCable::Channel::BaseTest::ChatChannel#invalid_action") do
-      @channel.perform_action 'action' => :invalid_action
+      @channel.perform_action "action" => :invalid_action
     end
   end
 
@@ -173,12 +184,12 @@ class ActionCable::Channel::BaseTest < ActiveSupport::TestCase
         events << ActiveSupport::Notifications::Event.new(*args)
       end
 
-      data = {'action' => :speak, 'content' => 'hello'}
+      data = { "action" => :speak, "content" => "hello" }
       @channel.perform_action data
 
       assert_equal 1, events.length
-      assert_equal 'perform_action.action_cable', events[0].name
-      assert_equal 'ActionCable::Channel::BaseTest::ChatChannel', events[0].payload[:channel_class]
+      assert_equal "perform_action.action_cable", events[0].name
+      assert_equal "ActionCable::Channel::BaseTest::ChatChannel", events[0].payload[:channel_class]
       assert_equal :speak, events[0].payload[:action]
       assert_equal data, events[0].payload[:data]
     ensure
@@ -189,27 +200,29 @@ class ActionCable::Channel::BaseTest < ActiveSupport::TestCase
   test "notification for transmit" do
     begin
       events = []
-      ActiveSupport::Notifications.subscribe 'transmit.action_cable' do |*args|
+      ActiveSupport::Notifications.subscribe "transmit.action_cable" do |*args|
         events << ActiveSupport::Notifications::Event.new(*args)
       end
 
-      @channel.perform_action 'action' => :get_latest
-      expected_data = {data: 'latest'}
+      @channel.perform_action "action" => :get_latest
+      expected_data = { data: "latest" }
 
       assert_equal 1, events.length
-      assert_equal 'transmit.action_cable', events[0].name
-      assert_equal 'ActionCable::Channel::BaseTest::ChatChannel', events[0].payload[:channel_class]
+      assert_equal "transmit.action_cable", events[0].name
+      assert_equal "ActionCable::Channel::BaseTest::ChatChannel", events[0].payload[:channel_class]
       assert_equal expected_data, events[0].payload[:data]
       assert_nil events[0].payload[:via]
     ensure
-      ActiveSupport::Notifications.unsubscribe 'transmit.action_cable'
+      ActiveSupport::Notifications.unsubscribe "transmit.action_cable"
     end
   end
 
   test "notification for transmit_subscription_confirmation" do
     begin
+      @channel.subscribe_to_channel
+
       events = []
-      ActiveSupport::Notifications.subscribe 'transmit_subscription_confirmation.action_cable' do |*args|
+      ActiveSupport::Notifications.subscribe "transmit_subscription_confirmation.action_cable" do |*args|
         events << ActiveSupport::Notifications::Event.new(*args)
       end
 
@@ -217,27 +230,27 @@ class ActionCable::Channel::BaseTest < ActiveSupport::TestCase
       @channel.send(:transmit_subscription_confirmation)
 
       assert_equal 1, events.length
-      assert_equal 'transmit_subscription_confirmation.action_cable', events[0].name
-      assert_equal 'ActionCable::Channel::BaseTest::ChatChannel', events[0].payload[:channel_class]
+      assert_equal "transmit_subscription_confirmation.action_cable", events[0].name
+      assert_equal "ActionCable::Channel::BaseTest::ChatChannel", events[0].payload[:channel_class]
     ensure
-      ActiveSupport::Notifications.unsubscribe 'transmit_subscription_confirmation.action_cable'
+      ActiveSupport::Notifications.unsubscribe "transmit_subscription_confirmation.action_cable"
     end
   end
 
   test "notification for transmit_subscription_rejection" do
     begin
       events = []
-      ActiveSupport::Notifications.subscribe 'transmit_subscription_rejection.action_cable' do |*args|
+      ActiveSupport::Notifications.subscribe "transmit_subscription_rejection.action_cable" do |*args|
         events << ActiveSupport::Notifications::Event.new(*args)
       end
 
       @channel.send(:transmit_subscription_rejection)
 
       assert_equal 1, events.length
-      assert_equal 'transmit_subscription_rejection.action_cable', events[0].name
-      assert_equal 'ActionCable::Channel::BaseTest::ChatChannel', events[0].payload[:channel_class]
+      assert_equal "transmit_subscription_rejection.action_cable", events[0].name
+      assert_equal "ActionCable::Channel::BaseTest::ChatChannel", events[0].payload[:channel_class]
     ensure
-      ActiveSupport::Notifications.unsubscribe 'transmit_subscription_rejection.action_cable'
+      ActiveSupport::Notifications.unsubscribe "transmit_subscription_rejection.action_cable"
     end
   end
 
diff --git a/actioncable/test/channel/broadcasting_test.rb b/actioncable/test/channel/broadcasting_test.rb
index 1de04243e5..ab58f33511 100644
--- a/actioncable/test/channel/broadcasting_test.rb
+++ b/actioncable/test/channel/broadcasting_test.rb
@@ -1,6 +1,8 @@
-require 'test_helper'
-require 'stubs/test_connection'
-require 'stubs/room'
+# frozen_string_literal: true
+
+require "test_helper"
+require "stubs/test_connection"
+require "stubs/room"
 
 class ActionCable::Channel::BroadcastingTest < ActiveSupport::TestCase
   class ChatChannel < ActionCable::Channel::Base
@@ -11,7 +13,7 @@ class ActionCable::Channel::BroadcastingTest < ActiveSupport::TestCase
   end
 
   test "broadcasts_to" do
-    ActionCable.stubs(:server).returns mock().tap { |m| m.expects(:broadcast).with('action_cable:channel:broadcasting_test:chat:Room#1-Campfire', "Hello World") }
+    ActionCable.stubs(:server).returns mock().tap { |m| m.expects(:broadcast).with("action_cable:channel:broadcasting_test:chat:Room#1-Campfire", "Hello World") }
     ChatChannel.broadcast_to(Room.new(1), "Hello World")
   end
 
diff --git a/actioncable/test/channel/naming_test.rb b/actioncable/test/channel/naming_test.rb
index 89ef6ad8b0..6f094fbb5e 100644
--- a/actioncable/test/channel/naming_test.rb
+++ b/actioncable/test/channel/naming_test.rb
@@ -1,4 +1,6 @@
-require 'test_helper'
+# frozen_string_literal: true
+
+require "test_helper"
 
 class ActionCable::Channel::NamingTest < ActiveSupport::TestCase
   class ChatChannel < ActionCable::Channel::Base
diff --git a/actioncable/test/channel/periodic_timers_test.rb b/actioncable/test/channel/periodic_timers_test.rb
index 03464003cf..500b984ca6 100644
--- a/actioncable/test/channel/periodic_timers_test.rb
+++ b/actioncable/test/channel/periodic_timers_test.rb
@@ -1,7 +1,9 @@
-require 'test_helper'
-require 'stubs/test_connection'
-require 'stubs/room'
-require 'active_support/time'
+# frozen_string_literal: true
+
+require "test_helper"
+require "stubs/test_connection"
+require "stubs/room"
+require "active_support/time"
 
 class ActionCable::Channel::PeriodicTimersTest < ActiveSupport::TestCase
   class ChatChannel < ActionCable::Channel::Base
@@ -32,36 +34,40 @@ class ActionCable::Channel::PeriodicTimersTest < ActiveSupport::TestCase
 
     timers.each_with_index do |timer, i|
       assert_kind_of Proc, timer[0]
-      assert_equal i+1, timer[1][:every]
+      assert_equal i + 1, timer[1][:every]
     end
   end
 
-  test 'disallow negative and zero periods' do
-    [ 0, 0.0, 0.seconds, -1, -1.seconds, 'foo', :foo, Object.new ].each do |invalid|
-      assert_raise ArgumentError, /Expected every:/ do
+  test "disallow negative and zero periods" do
+    [ 0, 0.0, 0.seconds, -1, -1.seconds, "foo", :foo, Object.new ].each do |invalid|
+      e = assert_raise ArgumentError do
         ChatChannel.periodically :send_updates, every: invalid
       end
+      assert_match(/Expected every:/, e.message)
     end
   end
 
-  test 'disallow block and arg together' do
-    assert_raise ArgumentError, /not both/ do
+  test "disallow block and arg together" do
+    e = assert_raise ArgumentError do
       ChatChannel.periodically(:send_updates, every: 1) { ping }
     end
+    assert_match(/not both/, e.message)
   end
 
-  test 'disallow unknown args' do
-    [ 'send_updates', Object.new, nil ].each do |invalid|
-      assert_raise ArgumentError, /Expected a Symbol/ do
+  test "disallow unknown args" do
+    [ "send_updates", Object.new, nil ].each do |invalid|
+      e = assert_raise ArgumentError do
         ChatChannel.periodically invalid, every: 1
       end
+      assert_match(/Expected a Symbol/, e.message)
     end
   end
 
   test "timer start and stop" do
     @connection.server.event_loop.expects(:timer).times(3).returns(stub(shutdown: nil))
-    channel = ChatChannel.new @connection, "{id: 1}", { id: 1 }
+    channel = ChatChannel.new @connection, "{id: 1}", id: 1
 
+    channel.subscribe_to_channel
     channel.unsubscribe_from_channel
     assert_equal [], channel.send(:active_periodic_timers)
   end
diff --git a/actioncable/test/channel/rejection_test.rb b/actioncable/test/channel/rejection_test.rb
index 15db57d6ba..a6da014a21 100644
--- a/actioncable/test/channel/rejection_test.rb
+++ b/actioncable/test/channel/rejection_test.rb
@@ -1,12 +1,17 @@
-require 'test_helper'
-require 'stubs/test_connection'
-require 'stubs/room'
+# frozen_string_literal: true
+
+require "test_helper"
+require "stubs/test_connection"
+require "stubs/room"
 
 class ActionCable::Channel::RejectionTest < ActiveSupport::TestCase
   class SecretChannel < ActionCable::Channel::Base
     def subscribed
       reject if params[:id] > 0
     end
+
+    def secret_action
+    end
   end
 
   setup do
@@ -16,10 +21,23 @@ class ActionCable::Channel::RejectionTest < ActiveSupport::TestCase
 
   test "subscription rejection" do
     @connection.expects(:subscriptions).returns mock().tap { |m| m.expects(:remove_subscription).with instance_of(SecretChannel) }
-    @channel = SecretChannel.new @connection, "{id: 1}", { id: 1 }
+    @channel = SecretChannel.new @connection, "{id: 1}", id: 1
+    @channel.subscribe_to_channel
 
     expected = { "identifier" => "{id: 1}", "type" => "reject_subscription" }
     assert_equal expected, @connection.last_transmission
   end
 
+  test "does not execute action if subscription is rejected" do
+    @connection.expects(:subscriptions).returns mock().tap { |m| m.expects(:remove_subscription).with instance_of(SecretChannel) }
+    @channel = SecretChannel.new @connection, "{id: 1}", id: 1
+    @channel.subscribe_to_channel
+
+    expected = { "identifier" => "{id: 1}", "type" => "reject_subscription" }
+    assert_equal expected, @connection.last_transmission
+    assert_equal 1, @connection.transmissions.size
+
+    @channel.perform_action("action" => :secret_action)
+    assert_equal 1, @connection.transmissions.size
+  end
 end
diff --git a/actioncable/test/channel/stream_test.rb b/actioncable/test/channel/stream_test.rb
index 38543920d3..eca06fe365 100644
--- a/actioncable/test/channel/stream_test.rb
+++ b/actioncable/test/channel/stream_test.rb
@@ -1,6 +1,8 @@
-require 'test_helper'
-require 'stubs/test_connection'
-require 'stubs/room'
+# frozen_string_literal: true
+
+require "test_helper"
+require "stubs/test_connection"
+require "stubs/room"
 
 module ActionCable::StreamTests
   class Connection < ActionCable::Connection::Base
@@ -25,11 +27,11 @@ module ActionCable::StreamTests
 
     private def pick_coder(coder)
       case coder
-      when nil, 'json'
+      when nil, "json"
         ActiveSupport::JSON
-      when 'custom'
+      when "custom"
         DummyEncoder
-      when 'none'
+      when "none"
         nil
       end
     end
@@ -38,7 +40,7 @@ module ActionCable::StreamTests
   module DummyEncoder
     extend self
     def encode(*) '{ "foo": "encoded" }' end
-    def decode(*) { foo: 'decoded' } end
+    def decode(*) { foo: "decoded" } end
   end
 
   class SymbolChannel < ActionCable::Channel::Base
@@ -52,7 +54,10 @@ module ActionCable::StreamTests
       run_in_eventmachine do
         connection = TestConnection.new
         connection.expects(:pubsub).returns mock().tap { |m| m.expects(:subscribe).with("test_room_1", kind_of(Proc), kind_of(Proc)).returns stub_everything(:pubsub) }
-        channel = ChatChannel.new connection, "{id: 1}", { id: 1 }
+        channel = ChatChannel.new connection, "{id: 1}", id: 1
+        channel.subscribe_to_channel
+
+        wait_for_async
 
         connection.expects(:pubsub).returns mock().tap { |m| m.expects(:unsubscribe) }
         channel.unsubscribe_from_channel
@@ -64,6 +69,9 @@ module ActionCable::StreamTests
         connection = TestConnection.new
         connection.expects(:pubsub).returns mock().tap { |m| m.expects(:subscribe).with("channel", kind_of(Proc), kind_of(Proc)).returns stub_everything(:pubsub) }
         channel = SymbolChannel.new connection, ""
+        channel.subscribe_to_channel
+
+        wait_for_async
 
         connection.expects(:pubsub).returns mock().tap { |m| m.expects(:unsubscribe) }
         channel.unsubscribe_from_channel
@@ -76,6 +84,7 @@ module ActionCable::StreamTests
         connection.expects(:pubsub).returns mock().tap { |m| m.expects(:subscribe).with("action_cable:stream_tests:chat:Room#1-Campfire", kind_of(Proc), kind_of(Proc)).returns stub_everything(:pubsub) }
 
         channel = ChatChannel.new connection, ""
+        channel.subscribe_to_channel
         channel.stream_for Room.new(1)
       end
     end
@@ -84,7 +93,9 @@ module ActionCable::StreamTests
       run_in_eventmachine do
         connection = TestConnection.new
 
-        ChatChannel.new connection, "{id: 1}", { id: 1 }
+        channel = ChatChannel.new connection, "{id: 1}", id: 1
+        channel.subscribe_to_channel
+
         assert_nil connection.last_transmission
 
         wait_for_async
@@ -114,7 +125,7 @@ module ActionCable::StreamTests
     end
   end
 
-  require 'action_cable/subscription_adapter/inline'
+  require "action_cable/subscription_adapter/async"
 
   class UserCallbackChannel < ActionCable::Channel::Base
     def subscribed
@@ -124,19 +135,26 @@ module ActionCable::StreamTests
     end
   end
 
-  class StreamEncodingTest < ActionCable::TestCase
+  class MultiChatChannel < ActionCable::Channel::Base
+    def subscribed
+      stream_from "main_room"
+      stream_from "test_all_rooms"
+    end
+  end
+
+  class StreamFromTest < ActionCable::TestCase
     setup do
-      @server = TestServer.new(subscription_adapter: ActionCable::SubscriptionAdapter::Inline)
+      @server = TestServer.new(subscription_adapter: ActionCable::SubscriptionAdapter::Async)
       @server.config.allowed_request_origins = %w( http://rubyonrails.com )
     end
 
-    test 'custom encoder' do
+    test "custom encoder" do
       run_in_eventmachine do
         connection = open_connection
         subscribe_to connection, identifiers: { id: 1 }
 
         connection.websocket.expects(:transmit)
-        @server.broadcast 'test_room_1', { foo: 'bar' }, coder: DummyEncoder
+        @server.broadcast "test_room_1", { foo: "bar" }, { coder: DummyEncoder }
         wait_for_async
         wait_for_executor connection.server.worker_pool.executor
       end
@@ -145,21 +163,32 @@ module ActionCable::StreamTests
     test "user supplied callbacks are run through the worker pool" do
       run_in_eventmachine do
         connection = open_connection
-        receive(connection, command: 'subscribe', channel: UserCallbackChannel.name, identifiers: { id: 1 })
+        receive(connection, command: "subscribe", channel: UserCallbackChannel.name, identifiers: { id: 1 })
 
-        @server.broadcast 'channel', {}
+        @server.broadcast "channel", {}
         wait_for_async
         refute Thread.current[:ran_callback], "User callback was not run through the worker pool"
       end
     end
 
+    test "subscription confirmation should only be sent out once with muptiple stream_from" do
+      run_in_eventmachine do
+        connection = open_connection
+        expected = { "identifier" => { "channel" => MultiChatChannel.name }.to_json, "type" => "confirm_subscription" }
+        connection.websocket.expects(:transmit).with(expected.to_json)
+        receive(connection, command: "subscribe", channel: MultiChatChannel.name, identifiers: {})
+
+        wait_for_async
+      end
+    end
+
     private
       def subscribe_to(connection, identifiers:)
-        receive connection, command: 'subscribe', identifiers: identifiers
+        receive connection, command: "subscribe", identifiers: identifiers
       end
 
       def open_connection
-        env = Rack::MockRequest.env_for '/test', 'HTTP_HOST' => 'localhost', 'HTTP_CONNECTION' => 'upgrade', 'HTTP_UPGRADE' => 'websocket', 'HTTP_ORIGIN' => 'http://rubyonrails.com'
+        env = Rack::MockRequest.env_for "/test", "HTTP_HOST" => "localhost", "HTTP_CONNECTION" => "upgrade", "HTTP_UPGRADE" => "websocket", "HTTP_ORIGIN" => "http://rubyonrails.com"
 
         Connection.new(@server, env).tap do |connection|
           connection.process
@@ -170,7 +199,7 @@ module ActionCable::StreamTests
         end
       end
 
-      def receive(connection, command:, identifiers:, channel: 'ActionCable::StreamTests::ChatChannel')
+      def receive(connection, command:, identifiers:, channel: "ActionCable::StreamTests::ChatChannel")
         identifier = JSON.generate(channel: channel, **identifiers)
         connection.dispatch_websocket_message JSON.generate(command: command, identifier: identifier)
         wait_for_async
diff --git a/actioncable/test/client_test.rb b/actioncable/test/client_test.rb
index f4b4a53aea..56b3ef143b 100644
--- a/actioncable/test/client_test.rb
+++ b/actioncable/test/client_test.rb
@@ -1,14 +1,33 @@
-require 'test_helper'
-require 'concurrent'
+# frozen_string_literal: true
 
-require 'active_support/core_ext/hash/indifferent_access'
-require 'pathname'
+require "test_helper"
+require "concurrent"
 
-require 'faye/websocket'
-require 'json'
+require "websocket-client-simple"
+require "json"
+
+require "active_support/hash_with_indifferent_access"
+
+####
+# 😷 Warning suppression 😷
+WebSocket::Frame::Handler::Handler03.prepend Module.new {
+  def initialize(*)
+    @application_data_buffer = nil
+    super
+  end
+}
+
+WebSocket::Frame::Data.prepend Module.new {
+  def initialize(*)
+    @masking_key = nil
+    super
+  end
+}
+#
+####
 
 class ClientTest < ActionCable::TestCase
-  WAIT_WHEN_EXPECTING_EVENT = 8
+  WAIT_WHEN_EXPECTING_EVENT = 2
   WAIT_WHEN_NOT_EXPECTING_EVENT = 0.5
 
   class EchoChannel < ActionCable::Channel::Base
@@ -17,20 +36,20 @@ class ClientTest < ActionCable::TestCase
     end
 
     def unsubscribed
-      'Goodbye from EchoChannel!'
+      "Goodbye from EchoChannel!"
     end
 
     def ding(data)
-      transmit(dong: data['message'])
+      transmit(dong: data["message"])
     end
 
     def delay(data)
       sleep 1
-      transmit(dong: data['message'])
+      transmit(dong: data["message"])
     end
 
     def bulk(data)
-      ActionCable.server.broadcast "global", wide: data['message']
+      ActionCable.server.broadcast "global", wide: data["message"]
     end
   end
 
@@ -39,79 +58,94 @@ class ClientTest < ActionCable::TestCase
     server = ActionCable.server
     server.config.logger = Logger.new(StringIO.new).tap { |l| l.level = Logger::UNKNOWN }
 
-    server.config.cable = { adapter: 'async' }.with_indifferent_access
-    server.config.use_faye = ENV['FAYE'].present?
+    server.config.cable = ActiveSupport::HashWithIndifferentAccess.new(adapter: "async")
 
     # and now the "real" setup for our test:
     server.config.disable_request_forgery_protection = true
-
-    Thread.new { EventMachine.run } unless EventMachine.reactor_running?
-    Thread.pass until EventMachine.reactor_running?
-
-    # faye-websocket is warning-rich
-    @previous_verbose, $VERBOSE = $VERBOSE, nil
-  end
-
-  def teardown
-    $VERBOSE = @previous_verbose
   end
 
   def with_puma_server(rack_app = ActionCable.server, port = 3099)
     server = ::Puma::Server.new(rack_app, ::Puma::Events.strings)
-    server.add_tcp_listener '127.0.0.1', port
+    server.add_tcp_listener "127.0.0.1", port
     server.min_threads = 1
     server.max_threads = 4
 
-    t = Thread.new { server.run.join }
-    yield port
+    thread = server.run
+
+    begin
+      yield port
+
+    ensure
+      server.stop
+
+      begin
+        thread.join
+
+      rescue IOError
+        # Work around https://bugs.ruby-lang.org/issues/13405
+        #
+        # Puma's sometimes raising while shutting down, when it closes
+        # its internal pipe. We can safely ignore that, but we do need
+        # to do the step skipped by the exception:
+        server.binder.close
+
+      rescue RuntimeError => ex
+        # Work around https://bugs.ruby-lang.org/issues/13239
+        raise unless ex.message =~ /can't modify frozen IOError/
 
-  ensure
-    server.stop(true) if server
-    t.join if t
+        # Handle this as if it were the IOError: do the same as above.
+        server.binder.close
+      end
+    end
   end
 
   class SyncClient
     attr_reader :pings
 
     def initialize(port)
-      @ws = Faye::WebSocket::Client.new("ws://127.0.0.1:#{port}/")
-      @messages = Queue.new
-      @closed = Concurrent::Event.new
-      @has_messages = Concurrent::Semaphore.new(0)
-      @pings = 0
-
-      open = Concurrent::Event.new
-      error = nil
-
-      @ws.on(:error) do |event|
-        if open.set?
-          @messages << RuntimeError.new(event.message)
-        else
-          error = event.message
-          open.set
+      messages = @messages = Queue.new
+      closed = @closed = Concurrent::Event.new
+      has_messages = @has_messages = Concurrent::Semaphore.new(0)
+      pings = @pings = Concurrent::AtomicFixnum.new(0)
+
+      open = Concurrent::Promise.new
+
+      @ws = WebSocket::Client::Simple.connect("ws://127.0.0.1:#{port}/") do |ws|
+        ws.on(:error) do |event|
+          event = RuntimeError.new(event.message) unless event.is_a?(Exception)
+
+          if open.pending?
+            open.fail(event)
+          else
+            messages << event
+            has_messages.release
+          end
         end
-      end
 
-      @ws.on(:open) do |event|
-        open.set
-      end
+        ws.on(:open) do |event|
+          open.set(true)
+        end
 
-      @ws.on(:message) do |event|
-        message = JSON.parse(event.data)
-        if message['type'] == 'ping'
-          @pings += 1
-        else
-          @messages << message
-          @has_messages.release
+        ws.on(:message) do |event|
+          if event.type == :close
+            closed.set
+          else
+            message = JSON.parse(event.data)
+            if message["type"] == "ping"
+              pings.increment
+            else
+              messages << message
+              has_messages.release
+            end
+          end
         end
-      end
 
-      @ws.on(:close) do |event|
-        @closed.set
+        ws.on(:close) do |event|
+          closed.set
+        end
       end
 
-      open.wait(WAIT_WHEN_EXPECTING_EVENT)
-      raise error if error
+      open.wait!(WAIT_WHEN_EXPECTING_EVENT)
     end
 
     def read_message
@@ -162,76 +196,80 @@ class ClientTest < ActionCable::TestCase
     end
   end
 
-  def faye_client(port)
+  def websocket_client(port)
     SyncClient.new(port)
   end
 
+  def concurrently(enum)
+    enum.map { |*x| Concurrent::Future.execute { yield(*x) } }.map(&:value!)
+  end
+
   def test_single_client
     with_puma_server do |port|
-      c = faye_client(port)
-      assert_equal({"type" => "welcome"}, c.read_message)  # pop the first welcome message off the stack
-      c.send_message command: 'subscribe', identifier: JSON.generate(channel: 'ClientTest::EchoChannel')
-      assert_equal({"identifier"=>"{\"channel\":\"ClientTest::EchoChannel\"}", "type"=>"confirm_subscription"}, c.read_message)
-      c.send_message command: 'message', identifier: JSON.generate(channel: 'ClientTest::EchoChannel'), data: JSON.generate(action: 'ding', message: 'hello')
-      assert_equal({"identifier"=>"{\"channel\":\"ClientTest::EchoChannel\"}", "message"=>{"dong"=>"hello"}}, c.read_message)
+      c = websocket_client(port)
+      assert_equal({ "type" => "welcome" }, c.read_message)  # pop the first welcome message off the stack
+      c.send_message command: "subscribe", identifier: JSON.generate(channel: "ClientTest::EchoChannel")
+      assert_equal({ "identifier" => "{\"channel\":\"ClientTest::EchoChannel\"}", "type" => "confirm_subscription" }, c.read_message)
+      c.send_message command: "message", identifier: JSON.generate(channel: "ClientTest::EchoChannel"), data: JSON.generate(action: "ding", message: "hello")
+      assert_equal({ "identifier" => "{\"channel\":\"ClientTest::EchoChannel\"}", "message" => { "dong" => "hello" } }, c.read_message)
       c.close
     end
   end
 
   def test_interacting_clients
     with_puma_server do |port|
-      clients = 10.times.map { faye_client(port) }
+      clients = concurrently(10.times) { websocket_client(port) }
 
       barrier_1 = Concurrent::CyclicBarrier.new(clients.size)
       barrier_2 = Concurrent::CyclicBarrier.new(clients.size)
 
-      clients.map {|c| Concurrent::Future.execute {
-        assert_equal({"type" => "welcome"}, c.read_message)  # pop the first welcome message off the stack
-        c.send_message command: 'subscribe', identifier: JSON.generate(channel: 'ClientTest::EchoChannel')
-        assert_equal({"identifier"=>'{"channel":"ClientTest::EchoChannel"}', "type"=>"confirm_subscription"}, c.read_message)
-        c.send_message command: 'message', identifier: JSON.generate(channel: 'ClientTest::EchoChannel'), data: JSON.generate(action: 'ding', message: 'hello')
-        assert_equal({"identifier"=>'{"channel":"ClientTest::EchoChannel"}', "message"=>{"dong"=>"hello"}}, c.read_message)
+      concurrently(clients) do |c|
+        assert_equal({ "type" => "welcome" }, c.read_message)  # pop the first welcome message off the stack
+        c.send_message command: "subscribe", identifier: JSON.generate(channel: "ClientTest::EchoChannel")
+        assert_equal({ "identifier" => '{"channel":"ClientTest::EchoChannel"}', "type" => "confirm_subscription" }, c.read_message)
+        c.send_message command: "message", identifier: JSON.generate(channel: "ClientTest::EchoChannel"), data: JSON.generate(action: "ding", message: "hello")
+        assert_equal({ "identifier" => '{"channel":"ClientTest::EchoChannel"}', "message" => { "dong" => "hello" } }, c.read_message)
         barrier_1.wait WAIT_WHEN_EXPECTING_EVENT
-        c.send_message command: 'message', identifier: JSON.generate(channel: 'ClientTest::EchoChannel'), data: JSON.generate(action: 'bulk', message: 'hello')
+        c.send_message command: "message", identifier: JSON.generate(channel: "ClientTest::EchoChannel"), data: JSON.generate(action: "bulk", message: "hello")
         barrier_2.wait WAIT_WHEN_EXPECTING_EVENT
         assert_equal clients.size, c.read_messages(clients.size).size
-      } }.each(&:wait!)
+      end
 
-      clients.map {|c| Concurrent::Future.execute { c.close } }.each(&:wait!)
+      concurrently(clients, &:close)
     end
   end
 
   def test_many_clients
     with_puma_server do |port|
-      clients = 100.times.map { faye_client(port) }
-
-      clients.map {|c| Concurrent::Future.execute {
-        assert_equal({"type" => "welcome"}, c.read_message)  # pop the first welcome message off the stack
-        c.send_message command: 'subscribe', identifier: JSON.generate(channel: 'ClientTest::EchoChannel')
-        assert_equal({"identifier"=>'{"channel":"ClientTest::EchoChannel"}', "type"=>"confirm_subscription"}, c.read_message)
-        c.send_message command: 'message', identifier: JSON.generate(channel: 'ClientTest::EchoChannel'), data: JSON.generate(action: 'ding', message: 'hello')
-        assert_equal({"identifier"=>'{"channel":"ClientTest::EchoChannel"}', "message"=>{"dong"=>"hello"}}, c.read_message)
-      } }.each(&:wait!)
+      clients = concurrently(100.times) { websocket_client(port) }
+
+      concurrently(clients) do |c|
+        assert_equal({ "type" => "welcome" }, c.read_message)  # pop the first welcome message off the stack
+        c.send_message command: "subscribe", identifier: JSON.generate(channel: "ClientTest::EchoChannel")
+        assert_equal({ "identifier" => '{"channel":"ClientTest::EchoChannel"}', "type" => "confirm_subscription" }, c.read_message)
+        c.send_message command: "message", identifier: JSON.generate(channel: "ClientTest::EchoChannel"), data: JSON.generate(action: "ding", message: "hello")
+        assert_equal({ "identifier" => '{"channel":"ClientTest::EchoChannel"}', "message" => { "dong" => "hello" } }, c.read_message)
+      end
 
-      clients.map {|c| Concurrent::Future.execute { c.close } }.each(&:wait!)
+      concurrently(clients, &:close)
     end
   end
 
   def test_disappearing_client
     with_puma_server do |port|
-      c = faye_client(port)
-      assert_equal({"type" => "welcome"}, c.read_message)  # pop the first welcome message off the stack
-      c.send_message command: 'subscribe', identifier: JSON.generate(channel: 'ClientTest::EchoChannel')
-      assert_equal({"identifier"=>"{\"channel\":\"ClientTest::EchoChannel\"}", "type"=>"confirm_subscription"}, c.read_message)
-      c.send_message command: 'message', identifier: JSON.generate(channel: 'ClientTest::EchoChannel'), data: JSON.generate(action: 'delay', message: 'hello')
+      c = websocket_client(port)
+      assert_equal({ "type" => "welcome" }, c.read_message)  # pop the first welcome message off the stack
+      c.send_message command: "subscribe", identifier: JSON.generate(channel: "ClientTest::EchoChannel")
+      assert_equal({ "identifier" => "{\"channel\":\"ClientTest::EchoChannel\"}", "type" => "confirm_subscription" }, c.read_message)
+      c.send_message command: "message", identifier: JSON.generate(channel: "ClientTest::EchoChannel"), data: JSON.generate(action: "delay", message: "hello")
       c.close # disappear before write
 
-      c = faye_client(port)
-      assert_equal({"type" => "welcome"}, c.read_message) # pop the first welcome message off the stack
-      c.send_message command: 'subscribe', identifier: JSON.generate(channel: 'ClientTest::EchoChannel')
-      assert_equal({"identifier"=>"{\"channel\":\"ClientTest::EchoChannel\"}", "type"=>"confirm_subscription"}, c.read_message)
-      c.send_message command: 'message', identifier: JSON.generate(channel: 'ClientTest::EchoChannel'), data: JSON.generate(action: 'ding', message: 'hello')
-      assert_equal({"identifier"=>'{"channel":"ClientTest::EchoChannel"}', "message"=>{"dong"=>"hello"}}, c.read_message)
+      c = websocket_client(port)
+      assert_equal({ "type" => "welcome" }, c.read_message) # pop the first welcome message off the stack
+      c.send_message command: "subscribe", identifier: JSON.generate(channel: "ClientTest::EchoChannel")
+      assert_equal({ "identifier" => "{\"channel\":\"ClientTest::EchoChannel\"}", "type" => "confirm_subscription" }, c.read_message)
+      c.send_message command: "message", identifier: JSON.generate(channel: "ClientTest::EchoChannel"), data: JSON.generate(action: "ding", message: "hello")
+      assert_equal({ "identifier" => '{"channel":"ClientTest::EchoChannel"}', "message" => { "dong" => "hello" } }, c.read_message)
       c.close # disappear before read
     end
   end
@@ -239,17 +277,17 @@ class ClientTest < ActionCable::TestCase
   def test_unsubscribe_client
     with_puma_server do |port|
       app = ActionCable.server
-      identifier = JSON.generate(channel: 'ClientTest::EchoChannel')
+      identifier = JSON.generate(channel: "ClientTest::EchoChannel")
 
-      c = faye_client(port)
-      assert_equal({"type" => "welcome"}, c.read_message)
-      c.send_message command: 'subscribe', identifier: identifier
-      assert_equal({"identifier"=>"{\"channel\":\"ClientTest::EchoChannel\"}", "type"=>"confirm_subscription"}, c.read_message)
+      c = websocket_client(port)
+      assert_equal({ "type" => "welcome" }, c.read_message)
+      c.send_message command: "subscribe", identifier: identifier
+      assert_equal({ "identifier" => "{\"channel\":\"ClientTest::EchoChannel\"}", "type" => "confirm_subscription" }, c.read_message)
       assert_equal(1, app.connections.count)
       assert(app.remote_connections.where(identifier: identifier))
 
       subscriptions = app.connections.first.subscriptions.send(:subscriptions)
-      assert_not_equal 0, subscriptions.size, 'Missing EchoChannel subscription'
+      assert_not_equal 0, subscriptions.size, "Missing EchoChannel subscription"
       channel = subscriptions.first[1]
       channel.expects(:unsubscribed)
       c.close
@@ -262,10 +300,10 @@ class ClientTest < ActionCable::TestCase
 
   def test_server_restart
     with_puma_server do |port|
-      c = faye_client(port)
-      assert_equal({"type" => "welcome"}, c.read_message)
-      c.send_message command: 'subscribe', identifier: JSON.generate(channel: 'ClientTest::EchoChannel')
-      assert_equal({"identifier"=>"{\"channel\":\"ClientTest::EchoChannel\"}", "type"=>"confirm_subscription"}, c.read_message)
+      c = websocket_client(port)
+      assert_equal({ "type" => "welcome" }, c.read_message)
+      c.send_message command: "subscribe", identifier: JSON.generate(channel: "ClientTest::EchoChannel")
+      assert_equal({ "identifier" => "{\"channel\":\"ClientTest::EchoChannel\"}", "type" => "confirm_subscription" }, c.read_message)
 
       ActionCable.server.restart
       c.wait_for_close
diff --git a/actioncable/test/connection/authorization_test.rb b/actioncable/test/connection/authorization_test.rb
index a0506cb9c0..7d039336b8 100644
--- a/actioncable/test/connection/authorization_test.rb
+++ b/actioncable/test/connection/authorization_test.rb
@@ -1,5 +1,7 @@
-require 'test_helper'
-require 'stubs/test_server'
+# frozen_string_literal: true
+
+require "test_helper"
+require "stubs/test_server"
 
 class ActionCable::Connection::AuthorizationTest < ActionCable::TestCase
   class Connection < ActionCable::Connection::Base
@@ -19,8 +21,8 @@ class ActionCable::Connection::AuthorizationTest < ActionCable::TestCase
       server = TestServer.new
       server.config.allowed_request_origins = %w( http://rubyonrails.com )
 
-      env = Rack::MockRequest.env_for "/test", 'HTTP_CONNECTION' => 'upgrade', 'HTTP_UPGRADE' => 'websocket',
-        'HTTP_HOST' => 'localhost', 'HTTP_ORIGIN' => 'http://rubyonrails.com'
+      env = Rack::MockRequest.env_for "/test", "HTTP_CONNECTION" => "upgrade", "HTTP_UPGRADE" => "websocket",
+        "HTTP_HOST" => "localhost", "HTTP_ORIGIN" => "http://rubyonrails.com"
 
       connection = Connection.new(server, env)
       connection.websocket.expects(:close)
diff --git a/actioncable/test/connection/base_test.rb b/actioncable/test/connection/base_test.rb
index d7e1041e68..99488e38c8 100644
--- a/actioncable/test/connection/base_test.rb
+++ b/actioncable/test/connection/base_test.rb
@@ -1,6 +1,8 @@
-require 'test_helper'
-require 'stubs/test_server'
-require 'active_support/core_ext/object/json'
+# frozen_string_literal: true
+
+require "test_helper"
+require "stubs/test_server"
+require "active_support/core_ext/object/json"
 
 class ActionCable::Connection::BaseTest < ActionCable::TestCase
   class Connection < ActionCable::Connection::Base
@@ -113,14 +115,14 @@ class ActionCable::Connection::BaseTest < ActionCable::TestCase
     run_in_eventmachine do
       class CallMeMaybe
         def call(*)
-          raise 'Do not call me!'
+          raise "Do not call me!"
         end
       end
 
       env = Rack::MockRequest.env_for(
         "/test",
-        { 'HTTP_CONNECTION' => 'upgrade', 'HTTP_UPGRADE' => 'websocket',
-          'HTTP_HOST' => 'localhost', 'HTTP_ORIGIN' => 'http://rubyonrails.org', 'rack.hijack' => CallMeMaybe.new }
+        "HTTP_CONNECTION" => "upgrade", "HTTP_UPGRADE" => "websocket",
+          "HTTP_HOST" => "localhost", "HTTP_ORIGIN" => "http://rubyonrails.org", "rack.hijack" => CallMeMaybe.new
       )
 
       connection = ActionCable::Connection::Base.new(@server, env)
@@ -131,8 +133,8 @@ class ActionCable::Connection::BaseTest < ActionCable::TestCase
 
   private
     def open_connection
-      env = Rack::MockRequest.env_for "/test", 'HTTP_CONNECTION' => 'upgrade', 'HTTP_UPGRADE' => 'websocket',
-        'HTTP_HOST' => 'localhost', 'HTTP_ORIGIN' => 'http://rubyonrails.com'
+      env = Rack::MockRequest.env_for "/test", "HTTP_CONNECTION" => "upgrade", "HTTP_UPGRADE" => "websocket",
+        "HTTP_HOST" => "localhost", "HTTP_ORIGIN" => "http://rubyonrails.com"
 
       Connection.new(@server, env)
     end
diff --git a/actioncable/test/connection/client_socket_test.rb b/actioncable/test/connection/client_socket_test.rb
index 4af071b4da..5c31690c8b 100644
--- a/actioncable/test/connection/client_socket_test.rb
+++ b/actioncable/test/connection/client_socket_test.rb
@@ -1,5 +1,7 @@
-require 'test_helper'
-require 'stubs/test_server'
+# frozen_string_literal: true
+
+require "test_helper"
+require "stubs/test_server"
 
 class ActionCable::Connection::ClientSocketTest < ActionCable::TestCase
   class Connection < ActionCable::Connection::Base
@@ -32,31 +34,57 @@ class ActionCable::Connection::ClientSocketTest < ActionCable::TestCase
     @server.config.allowed_request_origins = %w( http://rubyonrails.com )
   end
 
-  test 'delegate socket errors to on_error handler' do
-    skip if ENV['FAYE'].present?
-
+  test "delegate socket errors to on_error handler" do
     run_in_eventmachine do
       connection = open_connection
 
       # Internal hax = :(
       client = connection.websocket.send(:websocket)
-      client.instance_variable_get('@stream').expects(:write).raises('foo')
+      client.instance_variable_get("@stream").expects(:write).raises("foo")
       client.expects(:client_gone).never
 
-      client.write('boo')
+      client.write("boo")
       assert_equal %w[ foo ], connection.errors
     end
   end
 
+  test "closes hijacked i/o socket at shutdown" do
+    run_in_eventmachine do
+      connection = open_connection
+
+      client = connection.websocket.send(:websocket)
+      event = Concurrent::Event.new
+      client.instance_variable_get("@stream")
+        .instance_variable_get("@rack_hijack_io")
+        .define_singleton_method(:close) { event.set }
+      connection.close
+      event.wait
+    end
+  end
+
   private
     def open_connection
-      env = Rack::MockRequest.env_for '/test',
-        'HTTP_CONNECTION' => 'upgrade', 'HTTP_UPGRADE' => 'websocket',
-        'HTTP_HOST' => 'localhost', 'HTTP_ORIGIN' => 'http://rubyonrails.com'
-      env['rack.hijack'] = -> { env['rack.hijack_io'] = StringIO.new }
+      env = Rack::MockRequest.env_for "/test",
+        "HTTP_CONNECTION" => "upgrade", "HTTP_UPGRADE" => "websocket",
+        "HTTP_HOST" => "localhost", "HTTP_ORIGIN" => "http://rubyonrails.com"
+      io, client_io = \
+        begin
+          Socket.pair(Socket::AF_UNIX, Socket::SOCK_STREAM, 0)
+        rescue
+          StringIO.new
+        end
+      env["rack.hijack"] = -> { env["rack.hijack_io"] = io }
 
       Connection.new(@server, env).tap do |connection|
         connection.process
+        if client_io
+          # Make sure server returns handshake response
+          Timeout.timeout(1) do
+            loop do
+              break if client_io.readline == "\r\n"
+            end
+          end
+        end
         connection.send :handle_open
         assert connection.connected
       end
diff --git a/actioncable/test/connection/cross_site_forgery_test.rb b/actioncable/test/connection/cross_site_forgery_test.rb
index 2d516b0533..3e21138ffc 100644
--- a/actioncable/test/connection/cross_site_forgery_test.rb
+++ b/actioncable/test/connection/cross_site_forgery_test.rb
@@ -1,8 +1,10 @@
-require 'test_helper'
-require 'stubs/test_server'
+# frozen_string_literal: true
+
+require "test_helper"
+require "stubs/test_server"
 
 class ActionCable::Connection::CrossSiteForgeryTest < ActionCable::TestCase
-  HOST = 'rubyonrails.com'
+  HOST = "rubyonrails.com"
 
   class Connection < ActionCable::Connection::Base
     def send_async(method, *args)
@@ -13,44 +15,53 @@ class ActionCable::Connection::CrossSiteForgeryTest < ActionCable::TestCase
   setup do
     @server = TestServer.new
     @server.config.allowed_request_origins = %w( http://rubyonrails.com )
+    @server.config.allow_same_origin_as_host = false
   end
 
   teardown do
     @server.config.disable_request_forgery_protection = false
     @server.config.allowed_request_origins = []
+    @server.config.allow_same_origin_as_host = true
   end
 
   test "disable forgery protection" do
     @server.config.disable_request_forgery_protection = true
-    assert_origin_allowed 'http://rubyonrails.com'
-    assert_origin_allowed 'http://hax.com'
+    assert_origin_allowed "http://rubyonrails.com"
+    assert_origin_allowed "http://hax.com"
   end
 
   test "explicitly specified a single allowed origin" do
-    @server.config.allowed_request_origins = 'http://hax.com'
-    assert_origin_not_allowed 'http://rubyonrails.com'
-    assert_origin_allowed 'http://hax.com'
+    @server.config.allowed_request_origins = "http://hax.com"
+    assert_origin_not_allowed "http://rubyonrails.com"
+    assert_origin_allowed "http://hax.com"
   end
 
   test "explicitly specified multiple allowed origins" do
     @server.config.allowed_request_origins = %w( http://rubyonrails.com http://www.rubyonrails.com )
-    assert_origin_allowed 'http://rubyonrails.com'
-    assert_origin_allowed 'http://www.rubyonrails.com'
-    assert_origin_not_allowed 'http://hax.com'
+    assert_origin_allowed "http://rubyonrails.com"
+    assert_origin_allowed "http://www.rubyonrails.com"
+    assert_origin_not_allowed "http://hax.com"
   end
 
   test "explicitly specified a single regexp allowed origin" do
     @server.config.allowed_request_origins = /.*ha.*/
-    assert_origin_not_allowed 'http://rubyonrails.com'
-    assert_origin_allowed 'http://hax.com'
+    assert_origin_not_allowed "http://rubyonrails.com"
+    assert_origin_allowed "http://hax.com"
   end
 
   test "explicitly specified multiple regexp allowed origins" do
-    @server.config.allowed_request_origins = [/http:\/\/ruby.*/, /.*rai.s.*com/, 'string' ]
-    assert_origin_allowed 'http://rubyonrails.com'
-    assert_origin_allowed 'http://www.rubyonrails.com'
-    assert_origin_not_allowed 'http://hax.com'
-    assert_origin_not_allowed 'http://rails.co.uk'
+    @server.config.allowed_request_origins = [/http:\/\/ruby.*/, /.*rai.s.*com/, "string" ]
+    assert_origin_allowed "http://rubyonrails.com"
+    assert_origin_allowed "http://www.rubyonrails.com"
+    assert_origin_not_allowed "http://hax.com"
+    assert_origin_not_allowed "http://rails.co.uk"
+  end
+
+  test "allow same origin as host" do
+    @server.config.allow_same_origin_as_host = true
+    assert_origin_allowed "http://#{HOST}"
+    assert_origin_not_allowed "http://hax.com"
+    assert_origin_not_allowed "http://rails.co.uk"
   end
 
   private
@@ -75,7 +86,7 @@ class ActionCable::Connection::CrossSiteForgeryTest < ActionCable::TestCase
     end
 
     def env_for_origin(origin)
-      Rack::MockRequest.env_for "/test", 'HTTP_CONNECTION' => 'upgrade', 'HTTP_UPGRADE' => 'websocket', 'SERVER_NAME' => HOST,
-        'HTTP_HOST' => HOST, 'HTTP_ORIGIN' => origin
+      Rack::MockRequest.env_for "/test", "HTTP_CONNECTION" => "upgrade", "HTTP_UPGRADE" => "websocket", "SERVER_NAME" => HOST,
+        "HTTP_HOST" => HOST, "HTTP_ORIGIN" => origin
     end
 end
diff --git a/actioncable/test/connection/identifier_test.rb b/actioncable/test/connection/identifier_test.rb
index b48d9af809..6b6c8cd31a 100644
--- a/actioncable/test/connection/identifier_test.rb
+++ b/actioncable/test/connection/identifier_test.rb
@@ -1,6 +1,8 @@
-require 'test_helper'
-require 'stubs/test_server'
-require 'stubs/user'
+# frozen_string_literal: true
+
+require "test_helper"
+require "stubs/test_server"
+require "stubs/user"
 
 class ActionCable::Connection::IdentifierTest < ActionCable::TestCase
   class Connection < ActionCable::Connection::Base
@@ -23,9 +25,9 @@ class ActionCable::Connection::IdentifierTest < ActionCable::TestCase
 
   test "should subscribe to internal channel on open and unsubscribe on close" do
     run_in_eventmachine do
-      pubsub = mock('pubsub_adapter')
-      pubsub.expects(:subscribe).with('action_cable/User#lifo', kind_of(Proc))
-      pubsub.expects(:unsubscribe).with('action_cable/User#lifo', kind_of(Proc))
+      pubsub = mock("pubsub_adapter")
+      pubsub.expects(:subscribe).with("action_cable/User#lifo", kind_of(Proc))
+      pubsub.expects(:unsubscribe).with("action_cable/User#lifo", kind_of(Proc))
 
       server = TestServer.new
       server.stubs(:pubsub).returns(pubsub)
@@ -40,7 +42,7 @@ class ActionCable::Connection::IdentifierTest < ActionCable::TestCase
       open_connection_with_stubbed_pubsub
 
       @connection.websocket.expects(:close)
-      @connection.process_internal_message 'type' => 'disconnect'
+      @connection.process_internal_message "type" => "disconnect"
     end
   end
 
@@ -49,20 +51,20 @@ class ActionCable::Connection::IdentifierTest < ActionCable::TestCase
       open_connection_with_stubbed_pubsub
 
       @connection.websocket.expects(:close).never
-      @connection.process_internal_message 'type' => 'unknown'
+      @connection.process_internal_message "type" => "unknown"
     end
   end
 
-  protected
+  private
     def open_connection_with_stubbed_pubsub
       server = TestServer.new
-      server.stubs(:adapter).returns(stub_everything('adapter'))
+      server.stubs(:adapter).returns(stub_everything("adapter"))
 
       open_connection server: server
     end
 
     def open_connection(server:)
-      env = Rack::MockRequest.env_for "/test", 'HTTP_HOST' => 'localhost', 'HTTP_CONNECTION' => 'upgrade', 'HTTP_UPGRADE' => 'websocket'
+      env = Rack::MockRequest.env_for "/test", "HTTP_HOST" => "localhost", "HTTP_CONNECTION" => "upgrade", "HTTP_UPGRADE" => "websocket"
       @connection = Connection.new(server, env)
 
       @connection.process
diff --git a/actioncable/test/connection/multiple_identifiers_test.rb b/actioncable/test/connection/multiple_identifiers_test.rb
index 484e73bb30..7f90cb3876 100644
--- a/actioncable/test/connection/multiple_identifiers_test.rb
+++ b/actioncable/test/connection/multiple_identifiers_test.rb
@@ -1,6 +1,8 @@
-require 'test_helper'
-require 'stubs/test_server'
-require 'stubs/user'
+# frozen_string_literal: true
+
+require "test_helper"
+require "stubs/test_server"
+require "stubs/user"
 
 class ActionCable::Connection::MultipleIdentifiersTest < ActionCable::TestCase
   class Connection < ActionCable::Connection::Base
@@ -19,23 +21,19 @@ class ActionCable::Connection::MultipleIdentifiersTest < ActionCable::TestCase
     end
   end
 
-  protected
+  private
     def open_connection_with_stubbed_pubsub
       server = TestServer.new
-      server.stubs(:pubsub).returns(stub_everything('pubsub'))
+      server.stubs(:pubsub).returns(stub_everything("pubsub"))
 
       open_connection server: server
     end
 
     def open_connection(server:)
-      env = Rack::MockRequest.env_for "/test", 'HTTP_HOST' => 'localhost', 'HTTP_CONNECTION' => 'upgrade', 'HTTP_UPGRADE' => 'websocket'
+      env = Rack::MockRequest.env_for "/test", "HTTP_HOST" => "localhost", "HTTP_CONNECTION" => "upgrade", "HTTP_UPGRADE" => "websocket"
       @connection = Connection.new(server, env)
 
       @connection.process
       @connection.send :handle_open
     end
-
-    def close_connection
-      @connection.send :handle_close
-    end
 end
diff --git a/actioncable/test/connection/stream_test.rb b/actioncable/test/connection/stream_test.rb
index a7a61d8d6f..b0419b0994 100644
--- a/actioncable/test/connection/stream_test.rb
+++ b/actioncable/test/connection/stream_test.rb
@@ -1,5 +1,7 @@
-require 'test_helper'
-require 'stubs/test_server'
+# frozen_string_literal: true
+
+require "test_helper"
+require "stubs/test_server"
 
 class ActionCable::Connection::StreamTest < ActionCable::TestCase
   class Connection < ActionCable::Connection::Base
@@ -34,17 +36,15 @@ class ActionCable::Connection::StreamTest < ActionCable::TestCase
 
   [ EOFError, Errno::ECONNRESET ].each do |closed_exception|
     test "closes socket on #{closed_exception}" do
-      skip if ENV['FAYE'].present?
-
       run_in_eventmachine do
         connection = open_connection
 
         # Internal hax = :(
         client = connection.websocket.send(:websocket)
-        client.instance_variable_get('@stream').instance_variable_get('@rack_hijack_io').expects(:write).raises(closed_exception, 'foo')
+        client.instance_variable_get("@stream").instance_variable_get("@rack_hijack_io").expects(:write).raises(closed_exception, "foo")
         client.expects(:client_gone)
 
-        client.write('boo')
+        client.write("boo")
         assert_equal [], connection.errors
       end
     end
@@ -52,10 +52,10 @@ class ActionCable::Connection::StreamTest < ActionCable::TestCase
 
   private
     def open_connection
-      env = Rack::MockRequest.env_for '/test',
-        'HTTP_CONNECTION' => 'upgrade', 'HTTP_UPGRADE' => 'websocket',
-        'HTTP_HOST' => 'localhost', 'HTTP_ORIGIN' => 'http://rubyonrails.com'
-      env['rack.hijack'] = -> { env['rack.hijack_io'] = StringIO.new }
+      env = Rack::MockRequest.env_for "/test",
+        "HTTP_CONNECTION" => "upgrade", "HTTP_UPGRADE" => "websocket",
+        "HTTP_HOST" => "localhost", "HTTP_ORIGIN" => "http://rubyonrails.com"
+      env["rack.hijack"] = -> { env["rack.hijack_io"] = StringIO.new }
 
       Connection.new(@server, env).tap do |connection|
         connection.process
diff --git a/actioncable/test/connection/string_identifier_test.rb b/actioncable/test/connection/string_identifier_test.rb
index eca0c31060..4cb58e7fd0 100644
--- a/actioncable/test/connection/string_identifier_test.rb
+++ b/actioncable/test/connection/string_identifier_test.rb
@@ -1,5 +1,7 @@
-require 'test_helper'
-require 'stubs/test_server'
+# frozen_string_literal: true
+
+require "test_helper"
+require "stubs/test_server"
 
 class ActionCable::Connection::StringIdentifierTest < ActionCable::TestCase
   class Connection < ActionCable::Connection::Base
@@ -21,23 +23,19 @@ class ActionCable::Connection::StringIdentifierTest < ActionCable::TestCase
     end
   end
 
-  protected
+  private
     def open_connection_with_stubbed_pubsub
       @server = TestServer.new
-      @server.stubs(:pubsub).returns(stub_everything('pubsub'))
+      @server.stubs(:pubsub).returns(stub_everything("pubsub"))
 
       open_connection
     end
 
     def open_connection
-      env = Rack::MockRequest.env_for "/test", 'HTTP_HOST' => 'localhost', 'HTTP_CONNECTION' => 'upgrade', 'HTTP_UPGRADE' => 'websocket'
+      env = Rack::MockRequest.env_for "/test", "HTTP_HOST" => "localhost", "HTTP_CONNECTION" => "upgrade", "HTTP_UPGRADE" => "websocket"
       @connection = Connection.new(@server, env)
 
       @connection.process
       @connection.send :on_open
     end
-
-    def close_connection
-      @connection.send :on_close
-    end
 end
diff --git a/actioncable/test/connection/subscriptions_test.rb b/actioncable/test/connection/subscriptions_test.rb
index a5b1e5dcf3..149a40604a 100644
--- a/actioncable/test/connection/subscriptions_test.rb
+++ b/actioncable/test/connection/subscriptions_test.rb
@@ -1,4 +1,6 @@
-require 'test_helper'
+# frozen_string_literal: true
+
+require "test_helper"
 
 class ActionCable::Connection::SubscriptionsTest < ActionCable::TestCase
   class Connection < ActionCable::Connection::Base
@@ -25,7 +27,7 @@ class ActionCable::Connection::SubscriptionsTest < ActionCable::TestCase
   setup do
     @server = TestServer.new
 
-    @chat_identifier = ActiveSupport::JSON.encode(id: 1, channel: 'ActionCable::Connection::SubscriptionsTest::ChatChannel')
+    @chat_identifier = ActiveSupport::JSON.encode(id: 1, channel: "ActionCable::Connection::SubscriptionsTest::ChatChannel")
   end
 
   test "subscribe command" do
@@ -42,7 +44,7 @@ class ActionCable::Connection::SubscriptionsTest < ActionCable::TestCase
     run_in_eventmachine do
       setup_connection
 
-      @subscriptions.execute_command 'command' => 'subscribe'
+      @subscriptions.execute_command "command" => "subscribe"
       assert @subscriptions.identifiers.empty?
     end
   end
@@ -55,7 +57,7 @@ class ActionCable::Connection::SubscriptionsTest < ActionCable::TestCase
       channel = subscribe_to_chat_channel
       channel.expects(:unsubscribe_from_channel)
 
-      @subscriptions.execute_command 'command' => 'unsubscribe', 'identifier' => @chat_identifier
+      @subscriptions.execute_command "command" => "unsubscribe", "identifier" => @chat_identifier
       assert @subscriptions.identifiers.empty?
     end
   end
@@ -64,7 +66,7 @@ class ActionCable::Connection::SubscriptionsTest < ActionCable::TestCase
     run_in_eventmachine do
       setup_connection
 
-      @subscriptions.execute_command 'command' => 'unsubscribe'
+      @subscriptions.execute_command "command" => "unsubscribe"
       assert @subscriptions.identifiers.empty?
     end
   end
@@ -74,8 +76,8 @@ class ActionCable::Connection::SubscriptionsTest < ActionCable::TestCase
       setup_connection
       channel = subscribe_to_chat_channel
 
-      data = { 'content' => 'Hello World!', 'action' => 'speak' }
-      @subscriptions.execute_command 'command' => 'message', 'identifier' => @chat_identifier, 'data' => ActiveSupport::JSON.encode(data)
+      data = { "content" => "Hello World!", "action" => "speak" }
+      @subscriptions.execute_command "command" => "message", "identifier" => @chat_identifier, "data" => ActiveSupport::JSON.encode(data)
 
       assert_equal [ data ], channel.lines
     end
@@ -87,7 +89,7 @@ class ActionCable::Connection::SubscriptionsTest < ActionCable::TestCase
 
       channel1 = subscribe_to_chat_channel
 
-      channel2_id = ActiveSupport::JSON.encode(id: 2, channel: 'ActionCable::Connection::SubscriptionsTest::ChatChannel')
+      channel2_id = ActiveSupport::JSON.encode(id: 2, channel: "ActionCable::Connection::SubscriptionsTest::ChatChannel")
       channel2 = subscribe_to_chat_channel(channel2_id)
 
       channel1.expects(:unsubscribe_from_channel)
@@ -99,14 +101,14 @@ class ActionCable::Connection::SubscriptionsTest < ActionCable::TestCase
 
   private
     def subscribe_to_chat_channel(identifier = @chat_identifier)
-      @subscriptions.execute_command 'command' => 'subscribe', 'identifier' => identifier
+      @subscriptions.execute_command "command" => "subscribe", "identifier" => identifier
       assert_equal identifier, @subscriptions.identifiers.last
 
-      @subscriptions.send :find, 'identifier' => identifier
+      @subscriptions.send :find, "identifier" => identifier
     end
 
     def setup_connection
-      env = Rack::MockRequest.env_for "/test", 'HTTP_HOST' => 'localhost', 'HTTP_CONNECTION' => 'upgrade', 'HTTP_UPGRADE' => 'websocket'
+      env = Rack::MockRequest.env_for "/test", "HTTP_HOST" => "localhost", "HTTP_CONNECTION" => "upgrade", "HTTP_UPGRADE" => "websocket"
       @connection = Connection.new(@server, env)
 
       @subscriptions = ActionCable::Connection::Subscriptions.new(@connection)
diff --git a/actioncable/test/javascript/src/test_helpers/consumer_test_helper.coffee b/actioncable/test/javascript/src/test_helpers/consumer_test_helper.coffee
index 6b145dede8..a9e95c37f0 100644
--- a/actioncable/test/javascript/src/test_helpers/consumer_test_helper.coffee
+++ b/actioncable/test/javascript/src/test_helpers/consumer_test_helper.coffee
@@ -21,6 +21,16 @@ TestHelpers.consumerTest = (name, options = {}, callback) ->
       assert.equal clients.length, 1
       assert.equal clients[0].readyState, WebSocket.OPEN
 
+    server.broadcastTo = (subscription, data = {}, callback) ->
+      data.identifier = subscription.identifier
+
+      if data.message_type
+        data.type = ActionCable.INTERNAL.message_types[data.message_type]
+        delete data.message_type
+
+      server.send(JSON.stringify(data))
+      TestHelpers.defer(callback)
+
     done = ->
       consumer.disconnect()
       server.close()
diff --git a/actioncable/test/javascript/src/test_helpers/index.coffee b/actioncable/test/javascript/src/test_helpers/index.coffee
index d36524d9cc..c84cbbcb2c 100644
--- a/actioncable/test/javascript/src/test_helpers/index.coffee
+++ b/actioncable/test/javascript/src/test_helpers/index.coffee
@@ -4,5 +4,8 @@
 ActionCable.TestHelpers =
   testURL: "ws://cable.example.com/"
 
+  defer: (callback) ->
+    setTimeout(callback, 1)
+
 originalWebSocket = ActionCable.WebSocket
 QUnit.testDone -> ActionCable.WebSocket = originalWebSocket
diff --git a/actioncable/test/javascript/src/unit/consumer_test.coffee b/actioncable/test/javascript/src/unit/consumer_test.coffee
index cf8a592255..41445274eb 100644
--- a/actioncable/test/javascript/src/unit/consumer_test.coffee
+++ b/actioncable/test/javascript/src/unit/consumer_test.coffee
@@ -2,8 +2,11 @@
 {consumerTest} = ActionCable.TestHelpers
 
 module "ActionCable.Consumer", ->
-  consumerTest "#connect", connect: false, ({consumer, server, done}) ->
-    server.on("connection", done)
+  consumerTest "#connect", connect: false, ({consumer, server, assert, done}) ->
+    server.on "connection", ->
+      assert.equal consumer.connect(), false
+      done()
+
     consumer.connect()
 
   consumerTest "#disconnect", ({consumer, client, done}) ->
diff --git a/actioncable/test/javascript/src/unit/subscription_test.coffee b/actioncable/test/javascript/src/unit/subscription_test.coffee
new file mode 100644
index 0000000000..07027ed170
--- /dev/null
+++ b/actioncable/test/javascript/src/unit/subscription_test.coffee
@@ -0,0 +1,40 @@
+{module, test} = QUnit
+{consumerTest} = ActionCable.TestHelpers
+
+module "ActionCable.Subscription", ->
+  consumerTest "#initialized callback", ({server, consumer, assert, done}) ->
+    consumer.subscriptions.create "chat",
+      initialized: ->
+        assert.ok true
+        done()
+
+  consumerTest "#connected callback", ({server, consumer, assert, done}) ->
+    subscription = consumer.subscriptions.create "chat",
+      connected: ->
+        assert.ok true
+        done()
+
+    server.broadcastTo(subscription, message_type: "confirmation")
+
+  consumerTest "#disconnected callback", ({server, consumer, assert, done}) ->
+    subscription = consumer.subscriptions.create "chat",
+      disconnected: ->
+        assert.ok true
+        done()
+
+    server.broadcastTo subscription, message_type: "confirmation", ->
+      server.close()
+
+  consumerTest "#perform", ({consumer, server, assert, done}) ->
+    subscription = consumer.subscriptions.create "chat",
+      connected: ->
+        @perform(publish: "hi")
+
+    server.on "message", (message) ->
+      data = JSON.parse(message)
+      assert.equal data.identifier, subscription.identifier
+      assert.equal data.command, "message"
+      assert.deepEqual data.data, JSON.stringify(action: { publish: "hi" })
+      done()
+
+    server.broadcastTo(subscription, message_type: "confirmation")
diff --git a/actioncable/test/javascript/src/unit/subscriptions_test.coffee b/actioncable/test/javascript/src/unit/subscriptions_test.coffee
new file mode 100644
index 0000000000..170b370e4a
--- /dev/null
+++ b/actioncable/test/javascript/src/unit/subscriptions_test.coffee
@@ -0,0 +1,25 @@
+{module, test} = QUnit
+{consumerTest} = ActionCable.TestHelpers
+
+module "ActionCable.Subscriptions", ->
+  consumerTest "create subscription with channel string", ({consumer, server, assert, done}) ->
+    channel = "chat"
+
+    server.on "message", (message) ->
+      data = JSON.parse(message)
+      assert.equal data.command, "subscribe"
+      assert.equal data.identifier, JSON.stringify({channel})
+      done()
+
+    consumer.subscriptions.create(channel)
+
+  consumerTest "create subscription with channel object", ({consumer, server, assert, done}) ->
+    channel = channel: "chat", room: "action"
+
+    server.on "message", (message) ->
+      data = JSON.parse(message)
+      assert.equal data.command, "subscribe"
+      assert.equal data.identifier, JSON.stringify(channel)
+      done()
+
+    consumer.subscriptions.create(channel)
diff --git a/actioncable/test/server/base_test.rb b/actioncable/test/server/base_test.rb
new file mode 100644
index 0000000000..1312e45f49
--- /dev/null
+++ b/actioncable/test/server/base_test.rb
@@ -0,0 +1,35 @@
+# frozen_string_literal: true
+
+require "test_helper"
+require "stubs/test_server"
+require "active_support/core_ext/hash/indifferent_access"
+
+class BaseTest < ActiveSupport::TestCase
+  def setup
+    @server = ActionCable::Server::Base.new
+    @server.config.cable = { adapter: "async" }.with_indifferent_access
+  end
+
+  class FakeConnection
+    def close
+    end
+  end
+
+  test "#restart closes all open connections" do
+    conn = FakeConnection.new
+    @server.add_connection(conn)
+
+    conn.expects(:close)
+    @server.restart
+  end
+
+  test "#restart shuts down worker pool" do
+    @server.worker_pool.expects(:halt)
+    @server.restart
+  end
+
+  test "#restart shuts down pub/sub adapter" do
+    @server.pubsub.expects(:shutdown)
+    @server.restart
+  end
+end
diff --git a/actioncable/test/server/broadcasting_test.rb b/actioncable/test/server/broadcasting_test.rb
index 3b4a7eaf90..72cec26234 100644
--- a/actioncable/test/server/broadcasting_test.rb
+++ b/actioncable/test/server/broadcasting_test.rb
@@ -1,10 +1,9 @@
+# frozen_string_literal: true
+
 require "test_helper"
+require "stubs/test_server"
 
 class BroadcastingTest < ActiveSupport::TestCase
-  class TestServer
-    include ActionCable::Server::Broadcasting
-  end
-
   test "fetching a broadcaster converts the broadcasting queue to a string" do
     broadcasting = :test_queue
     server = TestServer.new
@@ -12,4 +11,52 @@ class BroadcastingTest < ActiveSupport::TestCase
 
     assert_equal "test_queue", broadcaster.broadcasting
   end
+
+  test "broadcast generates notification" do
+    begin
+      server = TestServer.new
+
+      events = []
+      ActiveSupport::Notifications.subscribe "broadcast.action_cable" do |*args|
+        events << ActiveSupport::Notifications::Event.new(*args)
+      end
+
+      broadcasting = "test_queue"
+      message = { body: "test message" }
+      server.broadcast(broadcasting, message)
+
+      assert_equal 1, events.length
+      assert_equal "broadcast.action_cable", events[0].name
+      assert_equal broadcasting, events[0].payload[:broadcasting]
+      assert_equal message, events[0].payload[:message]
+      assert_equal ActiveSupport::JSON, events[0].payload[:coder]
+    ensure
+      ActiveSupport::Notifications.unsubscribe "broadcast.action_cable"
+    end
+  end
+
+  test "broadcaster from broadcaster_for generates notification" do
+    begin
+      server = TestServer.new
+
+      events = []
+      ActiveSupport::Notifications.subscribe "broadcast.action_cable" do |*args|
+        events << ActiveSupport::Notifications::Event.new(*args)
+      end
+
+      broadcasting = "test_queue"
+      message = { body: "test message" }
+
+      broadcaster = server.broadcaster_for(broadcasting)
+      broadcaster.broadcast(message)
+
+      assert_equal 1, events.length
+      assert_equal "broadcast.action_cable", events[0].name
+      assert_equal broadcasting, events[0].payload[:broadcasting]
+      assert_equal message, events[0].payload[:message]
+      assert_equal ActiveSupport::JSON, events[0].payload[:coder]
+    ensure
+      ActiveSupport::Notifications.unsubscribe "broadcast.action_cable"
+    end
+  end
 end
diff --git a/actioncable/test/stubs/global_id.rb b/actioncable/test/stubs/global_id.rb
index 334f0d03e8..15fab6b8a7 100644
--- a/actioncable/test/stubs/global_id.rb
+++ b/actioncable/test/stubs/global_id.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class GlobalID
   attr_reader :uri
   delegate :to_param, :to_s, to: :uri
diff --git a/actioncable/test/stubs/room.rb b/actioncable/test/stubs/room.rb
index cd66a0b687..df7236f408 100644
--- a/actioncable/test/stubs/room.rb
+++ b/actioncable/test/stubs/room.rb
@@ -1,7 +1,9 @@
+# frozen_string_literal: true
+
 class Room
   attr_reader :id, :name
 
-  def initialize(id, name='Campfire')
+  def initialize(id, name = "Campfire")
     @id = id
     @name = name
   end
diff --git a/actioncable/test/stubs/test_adapter.rb b/actioncable/test/stubs/test_adapter.rb
index bbd142b287..c481046973 100644
--- a/actioncable/test/stubs/test_adapter.rb
+++ b/actioncable/test/stubs/test_adapter.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class SuccessAdapter < ActionCable::SubscriptionAdapter::Base
   def broadcast(channel, payload)
   end
diff --git a/actioncable/test/stubs/test_connection.rb b/actioncable/test/stubs/test_connection.rb
index 885450dda6..fdddd1159e 100644
--- a/actioncable/test/stubs/test_connection.rb
+++ b/actioncable/test/stubs/test_connection.rb
@@ -1,4 +1,6 @@
-require 'stubs/user'
+# frozen_string_literal: true
+
+require "stubs/user"
 
 class TestConnection
   attr_reader :identifiers, :logger, :current_user, :server, :transmissions
diff --git a/actioncable/test/stubs/test_server.rb b/actioncable/test/stubs/test_server.rb
index b86f422a13..0bc4625e28 100644
--- a/actioncable/test/stubs/test_server.rb
+++ b/actioncable/test/stubs/test_server.rb
@@ -1,4 +1,6 @@
-require 'ostruct'
+# frozen_string_literal: true
+
+require "ostruct"
 
 class TestServer
   include ActionCable::Server::Connections
@@ -10,14 +12,8 @@ class TestServer
     @logger = ActiveSupport::TaggedLogging.new ActiveSupport::Logger.new(StringIO.new)
 
     @config = OpenStruct.new(log_tags: [], subscription_adapter: subscription_adapter)
-    @config.use_faye = ENV['FAYE'].present?
-    @config.client_socket_class = if @config.use_faye
-                                    ActionCable::Connection::FayeClientSocket
-                                  else
-                                    ActionCable::Connection::ClientSocket
-                                  end
-
-     @mutex = Monitor.new
+
+    @mutex = Monitor.new
   end
 
   def pubsub
@@ -25,11 +21,9 @@ class TestServer
   end
 
   def event_loop
-    @event_loop ||= if @config.use_faye
-                      ActionCable::Connection::FayeEventLoop.new
-                    else
-                      ActionCable::Connection::StreamEventLoop.new
-                    end
+    @event_loop ||= ActionCable::Connection::StreamEventLoop.new.tap do |loop|
+      loop.instance_variable_set(:@executor, Concurrent.global_io_executor)
+    end
   end
 
   def worker_pool
diff --git a/actioncable/test/stubs/user.rb b/actioncable/test/stubs/user.rb
index a66b4f87d5..7894d1d9ae 100644
--- a/actioncable/test/stubs/user.rb
+++ b/actioncable/test/stubs/user.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class User
   attr_reader :name
 
diff --git a/actioncable/test/subscription_adapter/async_test.rb b/actioncable/test/subscription_adapter/async_test.rb
index 8f413f14c2..6e038259b5 100644
--- a/actioncable/test/subscription_adapter/async_test.rb
+++ b/actioncable/test/subscription_adapter/async_test.rb
@@ -1,5 +1,7 @@
-require 'test_helper'
-require_relative './common'
+# frozen_string_literal: true
+
+require "test_helper"
+require_relative "common"
 
 class AsyncAdapterTest < ActionCable::TestCase
   include CommonSubscriptionAdapterTest
@@ -12,6 +14,6 @@ class AsyncAdapterTest < ActionCable::TestCase
   end
 
   def cable_config
-    { adapter: 'async' }
+    { adapter: "async" }
   end
 end
diff --git a/actioncable/test/subscription_adapter/base_test.rb b/actioncable/test/subscription_adapter/base_test.rb
index 256dce673f..999dc0cba1 100644
--- a/actioncable/test/subscription_adapter/base_test.rb
+++ b/actioncable/test/subscription_adapter/base_test.rb
@@ -1,5 +1,7 @@
-require 'test_helper'
-require 'stubs/test_server'
+# frozen_string_literal: true
+
+require "test_helper"
+require "stubs/test_server"
 
 class ActionCable::SubscriptionAdapter::BaseTest < ActionCable::TestCase
   ## TEST THAT ERRORS ARE RETURNED FOR INHERITORS THAT DON'T OVERRIDE METHODS
@@ -15,59 +17,49 @@ class ActionCable::SubscriptionAdapter::BaseTest < ActionCable::TestCase
 
   test "#broadcast returns NotImplementedError by default" do
     assert_raises NotImplementedError do
-      BrokenAdapter.new(@server).broadcast('channel', 'payload')
+      BrokenAdapter.new(@server).broadcast("channel", "payload")
     end
   end
 
   test "#subscribe returns NotImplementedError by default" do
-    callback = lambda { puts 'callback' }
-    success_callback = lambda { puts 'success' }
+    callback = lambda { puts "callback" }
+    success_callback = lambda { puts "success" }
 
     assert_raises NotImplementedError do
-      BrokenAdapter.new(@server).subscribe('channel', callback, success_callback)
+      BrokenAdapter.new(@server).subscribe("channel", callback, success_callback)
     end
   end
 
   test "#unsubscribe returns NotImplementedError by default" do
-    callback = lambda { puts 'callback' }
+    callback = lambda { puts "callback" }
 
     assert_raises NotImplementedError do
-      BrokenAdapter.new(@server).unsubscribe('channel', callback)
+      BrokenAdapter.new(@server).unsubscribe("channel", callback)
     end
   end
 
   # TEST METHODS THAT ARE REQUIRED OF THE ADAPTER'S BACKEND STORAGE OBJECT
 
   test "#broadcast is implemented" do
-    broadcast = SuccessAdapter.new(@server).broadcast('channel', 'payload')
-
-    assert_respond_to(SuccessAdapter.new(@server), :broadcast)
-
     assert_nothing_raised do
-      broadcast
+      SuccessAdapter.new(@server).broadcast("channel", "payload")
     end
   end
 
   test "#subscribe is implemented" do
-    callback = lambda { puts 'callback' }
-    success_callback = lambda { puts 'success' }
-    subscribe = SuccessAdapter.new(@server).subscribe('channel', callback, success_callback)
-
-    assert_respond_to(SuccessAdapter.new(@server), :subscribe)
+    callback = lambda { puts "callback" }
+    success_callback = lambda { puts "success" }
 
     assert_nothing_raised do
-      subscribe
+      SuccessAdapter.new(@server).subscribe("channel", callback, success_callback)
     end
   end
 
   test "#unsubscribe is implemented" do
-    callback = lambda { puts 'callback' }
-    unsubscribe = SuccessAdapter.new(@server).unsubscribe('channel', callback)
-
-    assert_respond_to(SuccessAdapter.new(@server), :unsubscribe)
+    callback = lambda { puts "callback" }
 
     assert_nothing_raised do
-      unsubscribe
+      SuccessAdapter.new(@server).unsubscribe("channel", callback)
     end
   end
 end
diff --git a/actioncable/test/subscription_adapter/channel_prefix.rb b/actioncable/test/subscription_adapter/channel_prefix.rb
new file mode 100644
index 0000000000..3071facd9d
--- /dev/null
+++ b/actioncable/test/subscription_adapter/channel_prefix.rb
@@ -0,0 +1,38 @@
+# frozen_string_literal: true
+
+require "test_helper"
+
+class ActionCable::Server::WithIndependentConfig < ActionCable::Server::Base
+  # ActionCable::Server::Base defines config as a class variable.
+  # Need config to be an instance variable here as we're testing 2 separate configs
+  def config
+    @config ||= ActionCable::Server::Configuration.new
+  end
+end
+
+module ChannelPrefixTest
+  def test_channel_prefix
+    server2 = ActionCable::Server::WithIndependentConfig.new
+    server2.config.cable = alt_cable_config
+    server2.config.logger = Logger.new(StringIO.new).tap { |l| l.level = Logger::UNKNOWN }
+
+    adapter_klass = server2.config.pubsub_adapter
+
+    rx_adapter2 = adapter_klass.new(server2)
+    tx_adapter2 = adapter_klass.new(server2)
+
+    subscribe_as_queue("channel") do |queue|
+      subscribe_as_queue("channel", rx_adapter2) do |queue2|
+        @tx_adapter.broadcast("channel", "hello world")
+        tx_adapter2.broadcast("channel", "hello world 2")
+
+        assert_equal "hello world", queue.pop
+        assert_equal "hello world 2", queue2.pop
+      end
+    end
+  end
+
+  def alt_cable_config
+    cable_config.merge(channel_prefix: "foo")
+  end
+end
diff --git a/actioncable/test/subscription_adapter/common.rb b/actioncable/test/subscription_adapter/common.rb
index 285c690df0..c533a9f3eb 100644
--- a/actioncable/test/subscription_adapter/common.rb
+++ b/actioncable/test/subscription_adapter/common.rb
@@ -1,8 +1,10 @@
-require 'test_helper'
-require 'concurrent'
+# frozen_string_literal: true
 
-require 'active_support/core_ext/hash/indifferent_access'
-require 'pathname'
+require "test_helper"
+require "concurrent"
+
+require "active_support/core_ext/hash/indifferent_access"
+require "pathname"
 
 module CommonSubscriptionAdapterTest
   WAIT_WHEN_EXPECTING_EVENT = 3
@@ -11,7 +13,7 @@ module CommonSubscriptionAdapterTest
   def setup
     server = ActionCable::Server::Base.new
     server.config.cable = cable_config.with_indifferent_access
-    server.config.use_faye = ENV['FAYE'].present?
+    server.config.logger = Logger.new(StringIO.new).tap { |l| l.level = Logger::UNKNOWN }
 
     adapter_klass = server.config.pubsub_adapter
 
@@ -20,10 +22,9 @@ module CommonSubscriptionAdapterTest
   end
 
   def teardown
-    [@rx_adapter, @tx_adapter].uniq.each(&:shutdown)
+    [@rx_adapter, @tx_adapter].uniq.compact.each(&:shutdown)
   end
 
-
   def subscribe_as_queue(channel, adapter = @rx_adapter)
     queue = Queue.new
 
@@ -41,77 +42,90 @@ module CommonSubscriptionAdapterTest
     adapter.unsubscribe(channel, callback) if subscribed.set?
   end
 
-
   def test_subscribe_and_unsubscribe
-    subscribe_as_queue('channel') do |queue|
+    subscribe_as_queue("channel") do |queue|
     end
   end
 
   def test_basic_broadcast
-    subscribe_as_queue('channel') do |queue|
-      @tx_adapter.broadcast('channel', 'hello world')
+    subscribe_as_queue("channel") do |queue|
+      @tx_adapter.broadcast("channel", "hello world")
 
-      assert_equal 'hello world', queue.pop
+      assert_equal "hello world", queue.pop
     end
   end
 
   def test_broadcast_after_unsubscribe
     keep_queue = nil
-    subscribe_as_queue('channel') do |queue|
+    subscribe_as_queue("channel") do |queue|
       keep_queue = queue
 
-      @tx_adapter.broadcast('channel', 'hello world')
+      @tx_adapter.broadcast("channel", "hello world")
 
-      assert_equal 'hello world', queue.pop
+      assert_equal "hello world", queue.pop
     end
 
-    @tx_adapter.broadcast('channel', 'hello void')
+    @tx_adapter.broadcast("channel", "hello void")
 
     sleep WAIT_WHEN_NOT_EXPECTING_EVENT
     assert_empty keep_queue
   end
 
   def test_multiple_broadcast
-    subscribe_as_queue('channel') do |queue|
-      @tx_adapter.broadcast('channel', 'bananas')
-      @tx_adapter.broadcast('channel', 'apples')
+    subscribe_as_queue("channel") do |queue|
+      @tx_adapter.broadcast("channel", "bananas")
+      @tx_adapter.broadcast("channel", "apples")
 
       received = []
       2.times { received << queue.pop }
-      assert_equal ['apples', 'bananas'], received.sort
+      assert_equal ["apples", "bananas"], received.sort
     end
   end
 
   def test_identical_subscriptions
-    subscribe_as_queue('channel') do |queue|
-      subscribe_as_queue('channel') do |queue_2|
-        @tx_adapter.broadcast('channel', 'hello')
+    subscribe_as_queue("channel") do |queue|
+      subscribe_as_queue("channel") do |queue_2|
+        @tx_adapter.broadcast("channel", "hello")
 
-        assert_equal 'hello', queue_2.pop
+        assert_equal "hello", queue_2.pop
       end
 
-      assert_equal 'hello', queue.pop
+      assert_equal "hello", queue.pop
     end
   end
 
   def test_simultaneous_subscriptions
-    subscribe_as_queue('channel') do |queue|
-      subscribe_as_queue('other channel') do |queue_2|
-        @tx_adapter.broadcast('channel', 'apples')
-        @tx_adapter.broadcast('other channel', 'oranges')
+    subscribe_as_queue("channel") do |queue|
+      subscribe_as_queue("other channel") do |queue_2|
+        @tx_adapter.broadcast("channel", "apples")
+        @tx_adapter.broadcast("other channel", "oranges")
 
-        assert_equal 'apples', queue.pop
-        assert_equal 'oranges', queue_2.pop
+        assert_equal "apples", queue.pop
+        assert_equal "oranges", queue_2.pop
       end
     end
   end
 
   def test_channel_filtered_broadcast
-    subscribe_as_queue('channel') do |queue|
-      @tx_adapter.broadcast('other channel', 'one')
-      @tx_adapter.broadcast('channel', 'two')
+    subscribe_as_queue("channel") do |queue|
+      @tx_adapter.broadcast("other channel", "one")
+      @tx_adapter.broadcast("channel", "two")
+
+      assert_equal "two", queue.pop
+    end
+  end
 
-      assert_equal 'two', queue.pop
+  def test_long_identifiers
+    channel_1 = "a" * 100 + "1"
+    channel_2 = "a" * 100 + "2"
+    subscribe_as_queue(channel_1) do |queue|
+      subscribe_as_queue(channel_2) do |queue_2|
+        @tx_adapter.broadcast(channel_1, "apples")
+        @tx_adapter.broadcast(channel_2, "oranges")
+
+        assert_equal "apples", queue.pop
+        assert_equal "oranges", queue_2.pop
+      end
     end
   end
 end
diff --git a/actioncable/test/subscription_adapter/evented_redis_test.rb b/actioncable/test/subscription_adapter/evented_redis_test.rb
deleted file mode 100644
index 6d20e6ed78..0000000000
--- a/actioncable/test/subscription_adapter/evented_redis_test.rb
+++ /dev/null
@@ -1,21 +0,0 @@
-require 'test_helper'
-require_relative './common'
-
-class EventedRedisAdapterTest < ActionCable::TestCase
-  include CommonSubscriptionAdapterTest
-
-  def setup
-    super
-
-    # em-hiredis is warning-rich
-    @previous_verbose, $VERBOSE = $VERBOSE, nil
-  end
-
-  def teardown
-    $VERBOSE = @previous_verbose
-  end
-
-  def cable_config
-    { adapter: 'evented_redis', url: 'redis://127.0.0.1:6379/12' }
-  end
-end
diff --git a/actioncable/test/subscription_adapter/inline_test.rb b/actioncable/test/subscription_adapter/inline_test.rb
index 75ea51e6b3..6305626b2b 100644
--- a/actioncable/test/subscription_adapter/inline_test.rb
+++ b/actioncable/test/subscription_adapter/inline_test.rb
@@ -1,5 +1,7 @@
-require 'test_helper'
-require_relative './common'
+# frozen_string_literal: true
+
+require "test_helper"
+require_relative "common"
 
 class InlineAdapterTest < ActionCable::TestCase
   include CommonSubscriptionAdapterTest
@@ -12,6 +14,6 @@ class InlineAdapterTest < ActionCable::TestCase
   end
 
   def cable_config
-    { adapter: 'inline' }
+    { adapter: "inline" }
   end
 end
diff --git a/actioncable/test/subscription_adapter/postgresql_test.rb b/actioncable/test/subscription_adapter/postgresql_test.rb
index 214352a0b2..1c375188ba 100644
--- a/actioncable/test/subscription_adapter/postgresql_test.rb
+++ b/actioncable/test/subscription_adapter/postgresql_test.rb
@@ -1,18 +1,20 @@
-require 'test_helper'
-require_relative './common'
+# frozen_string_literal: true
 
-require 'active_record'
+require "test_helper"
+require_relative "common"
+
+require "active_record"
 
 class PostgresqlAdapterTest < ActionCable::TestCase
   include CommonSubscriptionAdapterTest
 
   def setup
-    database_config = { 'adapter' => 'postgresql', 'database' => 'activerecord_unittest' }
-    ar_tests = File.expand_path('../../../activerecord/test', __dir__)
+    database_config = { "adapter" => "postgresql", "database" => "activerecord_unittest" }
+    ar_tests = File.expand_path("../../../activerecord/test", __dir__)
     if Dir.exist?(ar_tests)
-      require File.join(ar_tests, 'config')
-      require File.join(ar_tests, 'support/config')
-      local_config = ARTest.config['arunit']
+      require File.join(ar_tests, "config")
+      require File.join(ar_tests, "support/config")
+      local_config = ARTest.config["connections"]["postgresql"]["arunit"]
       database_config.update local_config if local_config
     end
 
@@ -35,6 +37,6 @@ class PostgresqlAdapterTest < ActionCable::TestCase
   end
 
   def cable_config
-    { adapter: 'postgresql' }
+    { adapter: "postgresql" }
   end
 end
diff --git a/actioncable/test/subscription_adapter/redis_test.rb b/actioncable/test/subscription_adapter/redis_test.rb
index 4f34dd86c9..63823d6ef0 100644
--- a/actioncable/test/subscription_adapter/redis_test.rb
+++ b/actioncable/test/subscription_adapter/redis_test.rb
@@ -1,16 +1,47 @@
-require 'test_helper'
-require_relative './common'
+# frozen_string_literal: true
+
+require "test_helper"
+require_relative "common"
+require_relative "channel_prefix"
+
+require "active_support/testing/method_call_assertions"
+require "action_cable/subscription_adapter/redis"
 
 class RedisAdapterTest < ActionCable::TestCase
   include CommonSubscriptionAdapterTest
+  include ChannelPrefixTest
 
   def cable_config
-    { adapter: 'redis', driver: 'ruby', url: 'redis://127.0.0.1:6379/12' }
+    { adapter: "redis", driver: "ruby" }
   end
 end
 
 class RedisAdapterTest::Hiredis < RedisAdapterTest
   def cable_config
-    super.merge(driver: 'hiredis')
+    super.merge(driver: "hiredis")
+  end
+end
+
+class RedisAdapterTest::AlternateConfiguration < RedisAdapterTest
+  def cable_config
+    alt_cable_config = super.dup
+    alt_cable_config.delete(:url)
+    alt_cable_config.merge(host: "127.0.0.1", port: 6379, db: 12)
+  end
+end
+
+class RedisAdapterTest::Connector < ActiveSupport::TestCase
+  include ActiveSupport::Testing::MethodCallAssertions
+
+  test "slices url, host, port, db, and password from config" do
+    config = { url: 1, host: 2, port: 3, db: 4, password: 5 }
+
+    assert_called_with ::Redis, :new, [ config ] do
+      connect config.merge(other: "unrelated", stuff: "here")
+    end
+  end
+
+  def connect(config)
+    ActionCable::SubscriptionAdapter::Redis.redis_connector.call(config)
   end
 end
diff --git a/actioncable/test/subscription_adapter/subscriber_map_test.rb b/actioncable/test/subscription_adapter/subscriber_map_test.rb
new file mode 100644
index 0000000000..ed81099cbc
--- /dev/null
+++ b/actioncable/test/subscription_adapter/subscriber_map_test.rb
@@ -0,0 +1,19 @@
+# frozen_string_literal: true
+
+require "test_helper"
+
+class SubscriberMapTest < ActionCable::TestCase
+  test "broadcast should not change subscribers" do
+    setup_subscription_map
+    origin = @subscription_map.instance_variable_get(:@subscribers).dup
+
+    @subscription_map.broadcast("not_exist_channel", "")
+
+    assert_equal origin, @subscription_map.instance_variable_get(:@subscribers)
+  end
+
+  private
+    def setup_subscription_map
+      @subscription_map = ActionCable::SubscriptionAdapter::SubscriberMap.new
+    end
+end
diff --git a/actioncable/test/test_helper.rb b/actioncable/test/test_helper.rb
index 0a9ee7ce77..2a4611fb37 100644
--- a/actioncable/test/test_helper.rb
+++ b/actioncable/test/test_helper.rb
@@ -1,53 +1,21 @@
-require 'action_cable'
-require 'active_support/testing/autorun'
+# frozen_string_literal: true
 
-require 'puma'
-require 'mocha/setup'
-require 'rack/mock'
+require "action_cable"
+require "active_support/testing/autorun"
+
+require "puma"
+require "mocha/setup"
+require "rack/mock"
 
 begin
-  require 'byebug'
+  require "byebug"
 rescue LoadError
 end
 
 # Require all the stubs and models
-Dir[File.dirname(__FILE__) + '/stubs/*.rb'].each {|file| require file }
-
-if ENV['FAYE'].present?
-  require 'faye/websocket'
-  class << Faye::WebSocket
-    remove_method :ensure_reactor_running
-
-    # We don't want Faye to start the EM reactor in tests because it makes testing much harder.
-    # We want to be able to start and stop EM loop in tests to make things simpler.
-    def ensure_reactor_running
-      # no-op
-    end
-  end
-end
+Dir[File.expand_path("stubs/*.rb", __dir__)].each { |file| require file }
 
-module EventMachineConcurrencyHelpers
-  def wait_for_async
-    EM.run_deferred_callbacks
-  end
-
-  def run_in_eventmachine
-    failure = nil
-    EM.run do
-      begin
-        yield
-      rescue => ex
-        failure = ex
-      ensure
-        wait_for_async
-        EM.stop if EM.reactor_running?
-      end
-    end
-    raise failure if failure
-  end
-end
-
-module ConcurrentRubyConcurrencyHelpers
+class ActionCable::TestCase < ActiveSupport::TestCase
   def wait_for_async
     wait_for_executor Concurrent.global_io_executor
   end
@@ -56,18 +24,14 @@ module ConcurrentRubyConcurrencyHelpers
     yield
     wait_for_async
   end
-end
-
-class ActionCable::TestCase < ActiveSupport::TestCase
-  if ENV['FAYE'].present?
-    include EventMachineConcurrencyHelpers
-  else
-    include ConcurrentRubyConcurrencyHelpers
-  end
 
   def wait_for_executor(executor)
+    # do not wait forever, wait 2s
+    timeout = 2
     until executor.completed_task_count == executor.scheduled_task_count
       sleep 0.1
+      timeout -= 0.1
+      raise "Executor could not complete all tasks in 2 seconds" unless timeout > 0
     end
   end
 end
diff --git a/actioncable/test/worker_test.rb b/actioncable/test/worker_test.rb
index e2c81fe312..bc1f3e415a 100644
--- a/actioncable/test/worker_test.rb
+++ b/actioncable/test/worker_test.rb
@@ -1,4 +1,6 @@
-require 'test_helper'
+# frozen_string_literal: true
+
+require "test_helper"
 
 class WorkerTest < ActiveSupport::TestCase
   class Receiver
@@ -9,7 +11,7 @@ class WorkerTest < ActiveSupport::TestCase
     end
 
     def process(message)
-      @last_action =  [ :process, message ]
+      @last_action = [ :process, message ]
     end
 
     def connection
diff --git a/actionmailer/CHANGELOG.md b/actionmailer/CHANGELOG.md
index 3b9f503a0b..2836f0cfbc 100644
--- a/actionmailer/CHANGELOG.md
+++ b/actionmailer/CHANGELOG.md
@@ -1,6 +1,27 @@
-*   Exception handling: use `rescue_from` to handle exceptions raised by
-    mailer actions, by message delivery, and by deferred delivery jobs.
+## Rails 5.2.0.beta2 (November 28, 2017) ##
 
-    *Jeremy Daer*
+*   No changes.
 
-Please check [5-0-stable](https://github.com/rails/rails/blob/5-0-stable/actionmailer/CHANGELOG.md) for previous changes.
+
+## Rails 5.2.0.beta1 (November 27, 2017) ##
+
+*   Add `assert_enqueued_email_with` test helper.
+
+        assert_enqueued_email_with ContactMailer, :welcome do
+          ContactMailer.welcome.deliver_later
+        end
+
+    *Mikkel Malmberg*
+
+*   Allow Action Mailer classes to configure their delivery job.
+
+        class MyMailer < ApplicationMailer
+          self.delivery_job = MyCustomDeliveryJob
+
+          ...
+        end
+
+    *Matthew Mongeau*
+
+
+Please check [5-1-stable](https://github.com/rails/rails/blob/5-1-stable/actionmailer/CHANGELOG.md) for previous changes.
diff --git a/actionmailer/MIT-LICENSE b/actionmailer/MIT-LICENSE
index 8573eb1225..1cb3add0fc 100644
--- a/actionmailer/MIT-LICENSE
+++ b/actionmailer/MIT-LICENSE
@@ -1,4 +1,4 @@
-Copyright (c) 2004-2016 David Heinemeier Hansson
+Copyright (c) 2004-2018 David Heinemeier Hansson
 
 Permission is hereby granted, free of charge, to any person obtaining
 a copy of this software and associated documentation files (the
diff --git a/actionmailer/README.rdoc b/actionmailer/README.rdoc
index 397ebe4201..14dfb82234 100644
--- a/actionmailer/README.rdoc
+++ b/actionmailer/README.rdoc
@@ -148,7 +148,7 @@ The latest version of Action Mailer can be installed with RubyGems:
 
   $ gem install actionmailer
 
-Source code can be downloaded as part of the Rails project on GitHub
+Source code can be downloaded as part of the Rails project on GitHub:
 
 * https://github.com/rails/rails/tree/master/actionmailer
 
@@ -157,7 +157,7 @@ Source code can be downloaded as part of the Rails project on GitHub
 
 Action Mailer is released under the MIT license:
 
-* http://www.opensource.org/licenses/MIT
+* https://opensource.org/licenses/MIT
 
 
 == Support
@@ -166,7 +166,7 @@ API documentation is at
 
 * http://api.rubyonrails.org
 
-Bug reports can be filed for the Ruby on Rails project here:
+Bug reports for the Ruby on Rails project can be filed here:
 
 * https://github.com/rails/rails/issues
 
diff --git a/actionmailer/Rakefile b/actionmailer/Rakefile
index 416c9ee33a..6ac408e1cb 100644
--- a/actionmailer/Rakefile
+++ b/actionmailer/Rakefile
@@ -1,4 +1,6 @@
-require 'rake/testtask'
+# frozen_string_literal: true
+
+require "rake/testtask"
 
 desc "Default Task"
 task default: [ :test ]
@@ -8,7 +10,7 @@ task :package
 # Run the unit tests
 Rake::TestTask.new { |t|
   t.libs << "test"
-  t.pattern = 'test/**/*_test.rb'
+  t.pattern = "test/**/*_test.rb"
   t.warning = true
   t.verbose = true
   t.ruby_opts = ["--dev"] if defined?(JRUBY_VERSION)
@@ -17,7 +19,7 @@ Rake::TestTask.new { |t|
 namespace :test do
   task :isolated do
     Dir.glob("test/**/*_test.rb").all? do |file|
-      sh(Gem.ruby, '-w', '-Ilib:test', file)
-    end or raise "Failures"
+      sh(Gem.ruby, "-w", "-Ilib:test", file)
+    end || raise("Failures")
   end
 end
diff --git a/actionmailer/actionmailer.gemspec b/actionmailer/actionmailer.gemspec
index 25e3bcb2e9..b8a2e80bd3 100644
--- a/actionmailer/actionmailer.gemspec
+++ b/actionmailer/actionmailer.gemspec
@@ -1,28 +1,35 @@
-version = File.read(File.expand_path('../../RAILS_VERSION', __FILE__)).strip
+# frozen_string_literal: true
+
+version = File.read(File.expand_path("../RAILS_VERSION", __dir__)).strip
 
 Gem::Specification.new do |s|
   s.platform    = Gem::Platform::RUBY
-  s.name        = 'actionmailer'
+  s.name        = "actionmailer"
   s.version     = version
-  s.summary     = 'Email composition, delivery, and receiving framework (part of Rails).'
-  s.description = 'Email on Rails. Compose, deliver, receive, and test emails using the familiar controller/view pattern. First-class support for multipart email and attachments.'
+  s.summary     = "Email composition, delivery, and receiving framework (part of Rails)."
+  s.description = "Email on Rails. Compose, deliver, receive, and test emails using the familiar controller/view pattern. First-class support for multipart email and attachments."
+
+  s.required_ruby_version = ">= 2.2.2"
 
-  s.required_ruby_version = '>= 2.2.2'
+  s.license = "MIT"
 
-  s.license = 'MIT'
+  s.author   = "David Heinemeier Hansson"
+  s.email    = "david@loudthinking.com"
+  s.homepage = "http://rubyonrails.org"
 
-  s.author   = 'David Heinemeier Hansson'
-  s.email    = 'david@loudthinking.com'
-  s.homepage = 'http://rubyonrails.org'
+  s.files        = Dir["CHANGELOG.md", "README.rdoc", "MIT-LICENSE", "lib/**/*"]
+  s.require_path = "lib"
+  s.requirements << "none"
 
-  s.files        = Dir['CHANGELOG.md', 'README.rdoc', 'MIT-LICENSE', 'lib/**/*']
-  s.require_path = 'lib'
-  s.requirements << 'none'
+  s.metadata = {
+    "source_code_uri" => "https://github.com/rails/rails/tree/v#{version}/actionmailer",
+    "changelog_uri"   => "https://github.com/rails/rails/blob/v#{version}/actionmailer/CHANGELOG.md"
+  }
 
-  s.add_dependency 'actionpack', version
-  s.add_dependency 'actionview', version
-  s.add_dependency 'activejob', version
+  s.add_dependency "actionpack", version
+  s.add_dependency "actionview", version
+  s.add_dependency "activejob", version
 
-  s.add_dependency 'mail', ['~> 2.5', '>= 2.5.4']
-  s.add_dependency 'rails-dom-testing', '~> 2.0'
+  s.add_dependency "mail", ["~> 2.5", ">= 2.5.4"]
+  s.add_dependency "rails-dom-testing", "~> 2.0"
 end
diff --git a/actionmailer/bin/test b/actionmailer/bin/test
index 404cabba51..c53377cc97 100755
--- a/actionmailer/bin/test
+++ b/actionmailer/bin/test
@@ -1,4 +1,5 @@
 #!/usr/bin/env ruby
-COMPONENT_ROOT = File.expand_path("../../", __FILE__)
-require File.expand_path("../tools/test", COMPONENT_ROOT)
-exit Minitest.run(ARGV)
+# frozen_string_literal: true
+
+COMPONENT_ROOT = File.expand_path("..", __dir__)
+require_relative "../../tools/test"
diff --git a/actionmailer/lib/action_mailer.rb b/actionmailer/lib/action_mailer.rb
index 55c017e338..fabbdd1b25 100644
--- a/actionmailer/lib/action_mailer.rb
+++ b/actionmailer/lib/action_mailer.rb
@@ -1,5 +1,7 @@
+# frozen_string_literal: true
+
 #--
-# Copyright (c) 2004-2016 David Heinemeier Hansson
+# Copyright (c) 2004-2018 David Heinemeier Hansson
 #
 # Permission is hereby granted, free of charge, to any person obtaining
 # a copy of this software and associated documentation files (the
@@ -21,15 +23,16 @@
 # WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 #++
 
-require 'abstract_controller'
-require 'action_mailer/version'
+require "abstract_controller"
+require "action_mailer/version"
 
 # Common Active Support usage in Action Mailer
-require 'active_support/rails'
-require 'active_support/core_ext/class'
-require 'active_support/core_ext/module/attr_internal'
-require 'active_support/core_ext/string/inflections'
-require 'active_support/lazy_load_hooks'
+require "active_support"
+require "active_support/rails"
+require "active_support/core_ext/class"
+require "active_support/core_ext/module/attr_internal"
+require "active_support/core_ext/string/inflections"
+require "active_support/lazy_load_hooks"
 
 module ActionMailer
   extend ::ActiveSupport::Autoload
@@ -42,15 +45,16 @@ module ActionMailer
   autoload :DeliveryMethods
   autoload :InlinePreviewInterceptor
   autoload :MailHelper
+  autoload :Parameterized
   autoload :Preview
-  autoload :Previews, 'action_mailer/preview'
+  autoload :Previews, "action_mailer/preview"
   autoload :TestCase
   autoload :TestHelper
   autoload :MessageDelivery
   autoload :DeliveryJob
 end
 
-autoload :Mime, 'action_dispatch/http/mime_type'
+autoload :Mime, "action_dispatch/http/mime_type"
 
 ActiveSupport.on_load(:action_view) do
   ActionView::Base.default_formats ||= Mime::SET.symbols
diff --git a/actionmailer/lib/action_mailer/base.rb b/actionmailer/lib/action_mailer/base.rb
index e766221008..eb8ae59533 100644
--- a/actionmailer/lib/action_mailer/base.rb
+++ b/actionmailer/lib/action_mailer/base.rb
@@ -1,11 +1,13 @@
-require 'mail'
-require 'action_mailer/collector'
-require 'active_support/core_ext/string/inflections'
-require 'active_support/core_ext/hash/except'
-require 'active_support/core_ext/module/anonymous'
+# frozen_string_literal: true
 
-require 'action_mailer/log_subscriber'
-require 'action_mailer/rescuable'
+require "mail"
+require "action_mailer/collector"
+require "active_support/core_ext/string/inflections"
+require "active_support/core_ext/hash/except"
+require "active_support/core_ext/module/anonymous"
+
+require "action_mailer/log_subscriber"
+require "action_mailer/rescuable"
 
 module ActionMailer
   # Action Mailer allows you to send email from your application using a mailer model and views.
@@ -57,7 +59,7 @@ module ActionMailer
   # The hash passed to the mail method allows you to specify any header that a <tt>Mail::Message</tt>
   # will accept (any valid email header including optional fields).
   #
-  # The mail method, if not passed a block, will inspect your views and send all the views with
+  # The +mail+ method, if not passed a block, will inspect your views and send all the views with
   # the same name as the method, so the above action would send the +welcome.text.erb+ view
   # file as well as the +welcome.html.erb+ view file in a +multipart/alternative+ email.
   #
@@ -133,7 +135,10 @@ module ActionMailer
   #
   #   config.action_mailer.default_url_options = { host: "example.com" }
   #
-  # By default when <tt>config.force_ssl</tt> is true, URLs generated for hosts will use the HTTPS protocol.
+  # You can also define a <tt>default_url_options</tt> method on individual mailers to override these
+  # default settings per-mailer.
+  #
+  # By default when <tt>config.force_ssl</tt> is +true+, URLs generated for hosts will use the HTTPS protocol.
   #
   # = Sending mail
   #
@@ -208,6 +213,19 @@ module ActionMailer
   #       end
   #     end
   #
+  # You can also send attachments with html template, in this case you need to add body, attachments,
+  # and custom content type like this:
+  #
+  #     class NotifierMailer < ApplicationMailer
+  #       def welcome(recipient)
+  #         attachments["free_book.pdf"] = File.read("path/to/file.pdf")
+  #         mail(to: recipient,
+  #              subject: "New account information",
+  #              content_type: "text/html",
+  #              body: "<html><body>Hello there</body></html>")
+  #       end
+  #     end
+  #
   # = Inline Attachments
   #
   # You can also specify that a file should be displayed inline with other HTML. This is useful
@@ -275,20 +293,19 @@ module ActionMailer
   #             content_description: 'This is a description'
   #   end
   #
-  # Finally, Action Mailer also supports passing <tt>Proc</tt> objects into the default hash, so you
-  # can define methods that evaluate as the message is being generated:
+  # Finally, Action Mailer also supports passing <tt>Proc</tt> and <tt>Lambda</tt> objects into the default hash,
+  # so you can define methods that evaluate as the message is being generated:
   #
   #   class NotifierMailer < ApplicationMailer
-  #     default 'X-Special-Header' => Proc.new { my_method }
+  #     default 'X-Special-Header' => Proc.new { my_method }, to: -> { @inviter.email_address }
   #
   #     private
-  #
   #       def my_method
   #         'some complex call'
   #       end
   #   end
   #
-  # Note that the proc is evaluated right at the start of the mail message generation, so if you
+  # Note that the proc/lambda is evaluated right at the start of the mail message generation, so if you
   # set something in the default hash using a proc, and then set the same thing inside of your
   # mailer method, it will get overwritten by the mailer method.
   #
@@ -299,7 +316,7 @@ module ActionMailer
   #
   # = Callbacks
   #
-  # You can specify callbacks using before_action and after_action for configuring your messages.
+  # You can specify callbacks using <tt>before_action</tt> and <tt>after_action</tt> for configuring your messages.
   # This may be useful, for example, when you want to add default inline attachments for all
   # messages sent out by a certain mailer class:
   #
@@ -311,7 +328,6 @@ module ActionMailer
   #     end
   #
   #     private
-  #
   #       def add_inline_attachment!
   #         attachments.inline["footer.jpg"] = File.read('/path/to/filename.jpg')
   #       end
@@ -396,7 +412,7 @@ module ActionMailer
   #
   # * <tt>sendmail_settings</tt> - Allows you to override options for the <tt>:sendmail</tt> delivery method.
   #   * <tt>:location</tt> - The location of the sendmail executable. Defaults to <tt>/usr/sbin/sendmail</tt>.
-  #   * <tt>:arguments</tt> - The command line arguments. Defaults to <tt>-i -t</tt> with <tt>-f sender@address</tt>
+  #   * <tt>:arguments</tt> - The command line arguments. Defaults to <tt>-i</tt> with <tt>-f sender@address</tt>
   #     added automatically before the message is sent.
   #
   # * <tt>file_settings</tt> - Allows you to override options for the <tt>:file</tt> delivery method.
@@ -417,10 +433,11 @@ module ActionMailer
   # * <tt>deliveries</tt> - Keeps an array of all the emails sent out through the Action Mailer with
   #   <tt>delivery_method :test</tt>. Most useful for unit and functional testing.
   #
-  # * <tt>deliver_later_queue_name</tt> - The name of the queue used with <tt>deliver_later</tt>.
+  # * <tt>deliver_later_queue_name</tt> - The name of the queue used with <tt>deliver_later</tt>. Defaults to +mailers+.
   class Base < AbstractController::Base
     include DeliveryMethods
     include Rescuable
+    include Parameterized
     include Previews
 
     abstract!
@@ -444,8 +461,8 @@ module ActionMailer
 
     helper ActionMailer::MailHelper
 
-    class_attribute :default_params
-    self.default_params = {
+    class_attribute :delivery_job, default: ::ActionMailer::DeliveryJob
+    class_attribute :default_params, default: {
       mime_version: "1.0",
       charset:      "UTF-8",
       content_type: "text/plain",
@@ -544,9 +561,9 @@ module ActionMailer
         end
       end
 
-    protected
+    private
 
-      def set_payload_for_mail(payload, mail) #:nodoc:
+      def set_payload_for_mail(payload, mail)
         payload[:mailer]     = name
         payload[:message_id] = mail.message_id
         payload[:subject]    = mail.subject
@@ -558,7 +575,7 @@ module ActionMailer
         payload[:mail]       = mail.encoded
       end
 
-      def method_missing(method_name, *args) # :nodoc:
+      def method_missing(method_name, *args)
         if action_methods.include?(method_name.to_s)
           MessageDelivery.new(self, method_name, *args)
         else
@@ -566,19 +583,13 @@ module ActionMailer
         end
       end
 
-    private
-
-      def respond_to_missing?(method, include_all = false) #:nodoc:
-        action_methods.include?(method.to_s)
+      def respond_to_missing?(method, include_all = false)
+        action_methods.include?(method.to_s) || super
       end
     end
 
     attr_internal :message
 
-    # Instantiate a new mailer object. If +method_name+ is not +nil+, the mailer
-    # will be initialized according to the named method. If not, the mailer will
-    # remain uninitialized (useful when you only need to invoke the "receive"
-    # method, for instance).
     def initialize
       super()
       @_mail_was_called = false
@@ -588,7 +599,8 @@ module ActionMailer
     def process(method_name, *args) #:nodoc:
       payload = {
         mailer: self.class.name,
-        action: method_name
+        action: method_name,
+        args: args
       }
 
       ActiveSupport::Notifications.instrument("process.action_mailer", payload) do
@@ -598,10 +610,10 @@ module ActionMailer
     end
 
     class NullMail #:nodoc:
-      def body; '' end
+      def body; "" end
       def header; {} end
 
-      def respond_to?(string, include_all=false)
+      def respond_to?(string, include_all = false)
         true
       end
 
@@ -830,138 +842,140 @@ module ActionMailer
       message
     end
 
-    protected
-
-    # Used by #mail to set the content type of the message.
-    #
-    # It will use the given +user_content_type+, or multipart if the mail
-    # message has any attachments. If the attachments are inline, the content
-    # type will be "multipart/related", otherwise "multipart/mixed".
-    #
-    # If there is no content type passed in via headers, and there are no
-    # attachments, or the message is multipart, then the default content type is
-    # used.
-    def set_content_type(m, user_content_type, class_default)
-      params = m.content_type_parameters || {}
-      case
-      when user_content_type.present?
-        user_content_type
-      when m.has_attachments?
-        if m.attachments.detect(&:inline?)
-          ["multipart", "related", params]
+    private
+
+      # Used by #mail to set the content type of the message.
+      #
+      # It will use the given +user_content_type+, or multipart if the mail
+      # message has any attachments. If the attachments are inline, the content
+      # type will be "multipart/related", otherwise "multipart/mixed".
+      #
+      # If there is no content type passed in via headers, and there are no
+      # attachments, or the message is multipart, then the default content type is
+      # used.
+      def set_content_type(m, user_content_type, class_default) # :doc:
+        params = m.content_type_parameters || {}
+        case
+        when user_content_type.present?
+          user_content_type
+        when m.has_attachments?
+          if m.attachments.detect(&:inline?)
+            ["multipart", "related", params]
+          else
+            ["multipart", "mixed", params]
+          end
+        when m.multipart?
+          ["multipart", "alternative", params]
         else
-          ["multipart", "mixed", params]
+          m.content_type || class_default
         end
-      when m.multipart?
-        ["multipart", "alternative", params]
-      else
-        m.content_type || class_default
       end
-    end
 
-    # Translates the +subject+ using Rails I18n class under <tt>[mailer_scope, action_name]</tt> scope.
-    # If it does not find a translation for the +subject+ under the specified scope it will default to a
-    # humanized version of the <tt>action_name</tt>.
-    # If the subject has interpolations, you can pass them through the +interpolations+ parameter.
-    def default_i18n_subject(interpolations = {})
-      mailer_scope = self.class.mailer_name.tr('/', '.')
-      I18n.t(:subject, interpolations.merge(scope: [mailer_scope, action_name], default: action_name.humanize))
-    end
+      # Translates the +subject+ using Rails I18n class under <tt>[mailer_scope, action_name]</tt> scope.
+      # If it does not find a translation for the +subject+ under the specified scope it will default to a
+      # humanized version of the <tt>action_name</tt>.
+      # If the subject has interpolations, you can pass them through the +interpolations+ parameter.
+      def default_i18n_subject(interpolations = {}) # :doc:
+        mailer_scope = self.class.mailer_name.tr("/", ".")
+        I18n.t(:subject, interpolations.merge(scope: [mailer_scope, action_name], default: action_name.humanize))
+      end
 
-    # Emails do not support relative path links.
-    def self.supports_path?
-      false
-    end
+      # Emails do not support relative path links.
+      def self.supports_path? # :doc:
+        false
+      end
 
-    private
+      def apply_defaults(headers)
+        default_values = self.class.default.map do |key, value|
+          [
+            key,
+            value.is_a?(Proc) ? instance_exec(&value) : value
+          ]
+        end.to_h
+
+        headers_with_defaults = headers.reverse_merge(default_values)
+        headers_with_defaults[:subject] ||= default_i18n_subject
+        headers_with_defaults
+      end
 
-    def apply_defaults(headers)
-      default_values = self.class.default.map do |key, value|
-        [
-          key,
-          value.is_a?(Proc) ? instance_eval(&value) : value
-        ]
-      end.to_h
-
-      headers_with_defaults = headers.reverse_merge(default_values)
-      headers_with_defaults[:subject] ||= default_i18n_subject
-      headers_with_defaults
-    end
+      def assign_headers_to_message(message, headers)
+        assignable = headers.except(:parts_order, :content_type, :body, :template_name,
+                                    :template_path, :delivery_method, :delivery_method_options)
+        assignable.each { |k, v| message[k] = v }
+      end
 
-    def assign_headers_to_message(message, headers)
-      assignable = headers.except(:parts_order, :content_type, :body, :template_name,
-                                  :template_path, :delivery_method, :delivery_method_options)
-      assignable.each { |k, v| message[k] = v }
-    end
+      def collect_responses(headers)
+        if block_given?
+          collector = ActionMailer::Collector.new(lookup_context) { render(action_name) }
+          yield(collector)
+          collector.responses
+        elsif headers[:body]
+          collect_responses_from_text(headers)
+        else
+          collect_responses_from_templates(headers)
+        end
+      end
 
-    def collect_responses(headers)
-      if block_given?
-        collector = ActionMailer::Collector.new(lookup_context) { render(action_name) }
-        yield(collector)
-        collector.responses
-      elsif headers[:body]
+      def collect_responses_from_text(headers)
         [{
           body: headers.delete(:body),
-          content_type: self.class.default[:content_type] || "text/plain"
+          content_type: headers[:content_type] || "text/plain"
         }]
-      else
-        collect_responses_from_templates(headers)
       end
-    end
 
-    def collect_responses_from_templates(headers)
-      templates_path = headers[:template_path] || self.class.mailer_name
-      templates_name = headers[:template_name] || action_name
+      def collect_responses_from_templates(headers)
+        templates_path = headers[:template_path] || self.class.mailer_name
+        templates_name = headers[:template_name] || action_name
 
-      each_template(Array(templates_path), templates_name).map do |template|
-        self.formats = template.formats
-        {
-          body: render(template: template),
-          content_type: template.type.to_s
-        }
+        each_template(Array(templates_path), templates_name).map do |template|
+          self.formats = template.formats
+          {
+            body: render(template: template),
+            content_type: template.type.to_s
+          }
+        end
       end
-    end
 
-    def each_template(paths, name, &block)
-      templates = lookup_context.find_all(name, paths)
-      if templates.empty?
-        raise ActionView::MissingTemplate.new(paths, name, paths, false, 'mailer')
-      else
-        templates.uniq(&:formats).each(&block)
+      def each_template(paths, name, &block)
+        templates = lookup_context.find_all(name, paths)
+        if templates.empty?
+          raise ActionView::MissingTemplate.new(paths, name, paths, false, "mailer")
+        else
+          templates.uniq(&:formats).each(&block)
+        end
       end
-    end
 
-    def create_parts_from_responses(m, responses)
-      if responses.size == 1 && !m.has_attachments?
-        responses[0].each { |k,v| m[k] = v }
-      elsif responses.size > 1 && m.has_attachments?
-        container = Mail::Part.new
-        container.content_type = "multipart/alternative"
-        responses.each { |r| insert_part(container, r, m.charset) }
-        m.add_part(container)
-      else
-        responses.each { |r| insert_part(m, r, m.charset) }
+      def create_parts_from_responses(m, responses)
+        if responses.size == 1 && !m.has_attachments?
+          responses[0].each { |k, v| m[k] = v }
+        elsif responses.size > 1 && m.has_attachments?
+          container = Mail::Part.new
+          container.content_type = "multipart/alternative"
+          responses.each { |r| insert_part(container, r, m.charset) }
+          m.add_part(container)
+        else
+          responses.each { |r| insert_part(m, r, m.charset) }
+        end
       end
-    end
 
-    def insert_part(container, response, charset)
-      response[:charset] ||= charset
-      part = Mail::Part.new(response)
-      container.add_part(part)
-    end
+      def insert_part(container, response, charset)
+        response[:charset] ||= charset
+        part = Mail::Part.new(response)
+        container.add_part(part)
+      end
 
-    # This and #instrument_name is for caching instrument
-    def instrument_payload(key)
-      {
-        mailer: mailer_name,
-        key: key
-      }
-    end
+      # This and #instrument_name is for caching instrument
+      def instrument_payload(key)
+        {
+          mailer: mailer_name,
+          key: key
+        }
+      end
 
-    def instrument_name
-      "action_mailer"
-    end
+      def instrument_name
+        "action_mailer".freeze
+      end
 
-    ActiveSupport.run_load_hooks(:action_mailer, self)
+      ActiveSupport.run_load_hooks(:action_mailer, self)
   end
 end
diff --git a/actionmailer/lib/action_mailer/collector.rb b/actionmailer/lib/action_mailer/collector.rb
index e8883a8235..888410fa75 100644
--- a/actionmailer/lib/action_mailer/collector.rb
+++ b/actionmailer/lib/action_mailer/collector.rb
@@ -1,6 +1,8 @@
-require 'abstract_controller/collector'
-require 'active_support/core_ext/hash/reverse_merge'
-require 'active_support/core_ext/array/extract_options'
+# frozen_string_literal: true
+
+require "abstract_controller/collector"
+require "active_support/core_ext/hash/reverse_merge"
+require "active_support/core_ext/array/extract_options"
 
 module ActionMailer
   class Collector
diff --git a/actionmailer/lib/action_mailer/delivery_job.rb b/actionmailer/lib/action_mailer/delivery_job.rb
index d371c1b61a..40f26d8ad1 100644
--- a/actionmailer/lib/action_mailer/delivery_job.rb
+++ b/actionmailer/lib/action_mailer/delivery_job.rb
@@ -1,4 +1,6 @@
-require 'active_job'
+# frozen_string_literal: true
+
+require "active_job"
 
 module ActionMailer
   # The <tt>ActionMailer::DeliveryJob</tt> class is used when you
diff --git a/actionmailer/lib/action_mailer/delivery_methods.rb b/actionmailer/lib/action_mailer/delivery_methods.rb
index 571c8e7d2a..5cd62307e6 100644
--- a/actionmailer/lib/action_mailer/delivery_methods.rb
+++ b/actionmailer/lib/action_mailer/delivery_methods.rb
@@ -1,4 +1,6 @@
-require 'tmpdir'
+# frozen_string_literal: true
+
+require "tmpdir"
 
 module ActionMailer
   # This module handles everything related to mail delivery, from registering
@@ -7,25 +9,18 @@ module ActionMailer
     extend ActiveSupport::Concern
 
     included do
-      class_attribute :delivery_methods, :delivery_method
-
       # Do not make this inheritable, because we always want it to propagate
-      cattr_accessor :raise_delivery_errors
-      self.raise_delivery_errors = true
-
-      cattr_accessor :perform_deliveries
-      self.perform_deliveries = true
-
-      cattr_accessor :deliver_later_queue_name
-      self.deliver_later_queue_name = :mailers
+      cattr_accessor :raise_delivery_errors, default: true
+      cattr_accessor :perform_deliveries, default: true
+      cattr_accessor :deliver_later_queue_name, default: :mailers
 
-      self.delivery_methods = {}.freeze
-      self.delivery_method  = :smtp
+      class_attribute :delivery_methods, default: {}.freeze
+      class_attribute :delivery_method, default: :smtp
 
       add_delivery_method :smtp, Mail::SMTP,
         address:              "localhost",
         port:                 25,
-        domain:               'localhost.localdomain',
+        domain:               "localhost.localdomain",
         user_name:            nil,
         password:             nil,
         authentication:       nil,
@@ -35,8 +30,8 @@ module ActionMailer
         location: defined?(Rails.root) ? "#{Rails.root}/tmp/mails" : "#{Dir.tmpdir}/mails"
 
       add_delivery_method :sendmail, Mail::Sendmail,
-        location:  '/usr/sbin/sendmail',
-        arguments: '-i'
+        location:  "/usr/sbin/sendmail",
+        arguments: "-i"
 
       add_delivery_method :test, Mail::TestMailer
     end
@@ -51,15 +46,15 @@ module ActionMailer
       #
       #   add_delivery_method :sendmail, Mail::Sendmail,
       #     location:  '/usr/sbin/sendmail',
-      #     arguments: '-i -t'
-      def add_delivery_method(symbol, klass, default_options={})
+      #     arguments: '-i'
+      def add_delivery_method(symbol, klass, default_options = {})
         class_attribute(:"#{symbol}_settings") unless respond_to?(:"#{symbol}_settings")
         send(:"#{symbol}_settings=", default_options)
         self.delivery_methods = delivery_methods.merge(symbol.to_sym => klass).freeze
       end
 
-      def wrap_delivery_behavior(mail, method=nil, options=nil) # :nodoc:
-        method ||= self.delivery_method
+      def wrap_delivery_behavior(mail, method = nil, options = nil) # :nodoc:
+        method ||= delivery_method
         mail.delivery_handler = self
 
         case method
diff --git a/actionmailer/lib/action_mailer/gem_version.rb b/actionmailer/lib/action_mailer/gem_version.rb
index 7dafceef2b..6a7dd0a212 100644
--- a/actionmailer/lib/action_mailer/gem_version.rb
+++ b/actionmailer/lib/action_mailer/gem_version.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActionMailer
   # Returns the version of the currently loaded Action Mailer as a <tt>Gem::Version</tt>.
   def self.gem_version
@@ -6,9 +8,9 @@ module ActionMailer
 
   module VERSION
     MAJOR = 5
-    MINOR = 1
+    MINOR = 2
     TINY  = 0
-    PRE   = "alpha"
+    PRE   = "beta2"
 
     STRING = [MAJOR, MINOR, TINY, PRE].compact.join(".")
   end
diff --git a/actionmailer/lib/action_mailer/inline_preview_interceptor.rb b/actionmailer/lib/action_mailer/inline_preview_interceptor.rb
index 419d6c7b93..4bef4a58d3 100644
--- a/actionmailer/lib/action_mailer/inline_preview_interceptor.rb
+++ b/actionmailer/lib/action_mailer/inline_preview_interceptor.rb
@@ -1,4 +1,6 @@
-require 'base64'
+# frozen_string_literal: true
+
+require "base64"
 
 module ActionMailer
   # Implements a mailer preview interceptor that converts image tag src attributes
@@ -11,7 +13,7 @@ module ActionMailer
   #   ActionMailer::Base.preview_interceptors.delete(ActionMailer::InlinePreviewInterceptor)
   #
   class InlinePreviewInterceptor
-    PATTERN  = /src=(?:"cid:[^"]+"|'cid:[^']+')/i
+    PATTERN = /src=(?:"cid:[^"]+"|'cid:[^']+')/i
 
     include Base64
 
@@ -26,7 +28,7 @@ module ActionMailer
     def transform! #:nodoc:
       return message if html_part.blank?
 
-      html_source.gsub!(PATTERN) do |match|
+      html_part.body = html_part.decoded.gsub(PATTERN) do |match|
         if part = find_part(match[9..-2])
           %[src="#{data_url(part)}"]
         else
@@ -46,16 +48,12 @@ module ActionMailer
         @html_part ||= message.html_part
       end
 
-      def html_source
-        html_part.body.raw_source
-      end
-
       def data_url(part)
         "data:#{part.mime_type};base64,#{strict_encode64(part.body.raw_source)}"
       end
 
       def find_part(cid)
-        message.all_parts.find{ |p| p.attachment? && p.cid == cid }
+        message.all_parts.find { |p| p.attachment? && p.cid == cid }
       end
   end
 end
diff --git a/actionmailer/lib/action_mailer/log_subscriber.rb b/actionmailer/lib/action_mailer/log_subscriber.rb
index 2867bf90fb..87cfbfff28 100644
--- a/actionmailer/lib/action_mailer/log_subscriber.rb
+++ b/actionmailer/lib/action_mailer/log_subscriber.rb
@@ -1,4 +1,6 @@
-require 'active_support/log_subscriber'
+# frozen_string_literal: true
+
+require "active_support/log_subscriber"
 
 module ActionMailer
   # Implements the ActiveSupport::LogSubscriber for logging notifications when
@@ -7,7 +9,7 @@ module ActionMailer
     # An email was delivered.
     def deliver(event)
       info do
-        recipients = Array(event.payload[:to]).join(', ')
+        recipients = Array(event.payload[:to]).join(", ")
         "Sent mail to #{recipients} (#{event.duration.round(1)}ms)"
       end
 
diff --git a/actionmailer/lib/action_mailer/mail_helper.rb b/actionmailer/lib/action_mailer/mail_helper.rb
index 239974e7b1..e7bed41f8d 100644
--- a/actionmailer/lib/action_mailer/mail_helper.rb
+++ b/actionmailer/lib/action_mailer/mail_helper.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActionMailer
   # Provides helper methods for ActionMailer::Base that can be used for easily
   # formatting messages, accessing mailer or message instances, and the
@@ -54,7 +56,7 @@ module ActionMailer
       sentences = [[]]
 
       text.split.each do |word|
-        if sentences.first.present? && (sentences.last + [word]).join(' ').length > len
+        if sentences.first.present? && (sentences.last + [word]).join(" ").length > len
           sentences << [word]
         else
           sentences.last << word
diff --git a/actionmailer/lib/action_mailer/message_delivery.rb b/actionmailer/lib/action_mailer/message_delivery.rb
index c5ba5f9f1d..a2ea45dc7b 100644
--- a/actionmailer/lib/action_mailer/message_delivery.rb
+++ b/actionmailer/lib/action_mailer/message_delivery.rb
@@ -1,8 +1,10 @@
-require 'delegate'
+# frozen_string_literal: true
+
+require "delegate"
 
 module ActionMailer
   # The <tt>ActionMailer::MessageDelivery</tt> class is used by
-  # <tt>ActionMailer::Base</tt> when creating a new mailer.
+  # ActionMailer::Base when creating a new mailer.
   # <tt>MessageDelivery</tt> is a wrapper (+Delegator+ subclass) around a lazy
   # created <tt>Mail::Message</tt>. You can get direct access to the
   # <tt>Mail::Message</tt>, deliver the email or schedule the email to be sent
@@ -51,12 +53,20 @@ module ActionMailer
     #   Notifier.welcome(User.first).deliver_later!(wait: 1.hour)
     #   Notifier.welcome(User.first).deliver_later!(wait_until: 10.hours.from_now)
     #
+    # By default, the email will be enqueued using <tt>ActionMailer::DeliveryJob</tt>. Each
+    # <tt>ActionMailer::Base</tt> class can specify the job to use by setting the class variable
+    # +delivery_job+.
+    #
+    #   class AccountRegistrationMailer < ApplicationMailer
+    #     self.delivery_job = RegistrationDeliveryJob
+    #   end
+    #
     # Options:
     #
     # * <tt>:wait</tt> - Enqueue the email to be delivered with a delay
     # * <tt>:wait_until</tt> - Enqueue the email to be delivered at (after) a specific date / time
     # * <tt>:queue</tt> - Enqueue the email on the specified queue
-    def deliver_later!(options={})
+    def deliver_later!(options = {})
       enqueue_delivery :deliver_now!, options
     end
 
@@ -67,12 +77,20 @@ module ActionMailer
     #   Notifier.welcome(User.first).deliver_later(wait: 1.hour)
     #   Notifier.welcome(User.first).deliver_later(wait_until: 10.hours.from_now)
     #
+    # By default, the email will be enqueued using <tt>ActionMailer::DeliveryJob</tt>. Each
+    # <tt>ActionMailer::Base</tt> class can specify the job to use by setting the class variable
+    # +delivery_job+.
+    #
+    #   class AccountRegistrationMailer < ApplicationMailer
+    #     self.delivery_job = RegistrationDeliveryJob
+    #   end
+    #
     # Options:
     #
     # * <tt>:wait</tt> - Enqueue the email to be delivered with a delay.
     # * <tt>:wait_until</tt> - Enqueue the email to be delivered at (after) a specific date / time.
     # * <tt>:queue</tt> - Enqueue the email on the specified queue.
-    def deliver_later(options={})
+    def deliver_later(options = {})
       enqueue_delivery :deliver_now, options
     end
 
@@ -106,7 +124,7 @@ module ActionMailer
         end
       end
 
-      def enqueue_delivery(delivery_method, options={})
+      def enqueue_delivery(delivery_method, options = {})
         if processed?
           ::Kernel.raise "You've accessed the message before asking to " \
             "deliver it later, so you may have made local changes that would " \
@@ -118,7 +136,8 @@ module ActionMailer
             "method*, or 3. use a custom Active Job instead of #deliver_later."
         else
           args = @mailer_class.name, @action.to_s, delivery_method.to_s, *@args
-          ::ActionMailer::DeliveryJob.set(options).perform_later(*args)
+          job = @mailer_class.delivery_job
+          job.set(options).perform_later(*args)
         end
       end
   end
diff --git a/actionmailer/lib/action_mailer/parameterized.rb b/actionmailer/lib/action_mailer/parameterized.rb
new file mode 100644
index 0000000000..5e768e7106
--- /dev/null
+++ b/actionmailer/lib/action_mailer/parameterized.rb
@@ -0,0 +1,154 @@
+# frozen_string_literal: true
+
+module ActionMailer
+  # Provides the option to parameterize mailers in order to share instance variable
+  # setup, processing, and common headers.
+  #
+  # Consider this example that does not use parameterization:
+  #
+  #   class InvitationsMailer < ApplicationMailer
+  #     def account_invitation(inviter, invitee)
+  #       @account = inviter.account
+  #       @inviter = inviter
+  #       @invitee = invitee
+  #
+  #       subject = "#{@inviter.name} invited you to their Basecamp (#{@account.name})"
+  #
+  #       mail \
+  #         subject:   subject,
+  #         to:        invitee.email_address,
+  #         from:      common_address(inviter),
+  #         reply_to:  inviter.email_address_with_name
+  #     end
+  #
+  #     def project_invitation(project, inviter, invitee)
+  #       @account = inviter.account
+  #       @project = project
+  #       @inviter = inviter
+  #       @invitee = invitee
+  #       @summarizer = ProjectInvitationSummarizer.new(@project.bucket)
+  #
+  #       subject = "#{@inviter.name.familiar} added you to a project in Basecamp (#{@account.name})"
+  #
+  #       mail \
+  #         subject:   subject,
+  #         to:        invitee.email_address,
+  #         from:      common_address(inviter),
+  #         reply_to:  inviter.email_address_with_name
+  #     end
+  #
+  #     def bulk_project_invitation(projects, inviter, invitee)
+  #       @account  = inviter.account
+  #       @projects = projects.sort_by(&:name)
+  #       @inviter  = inviter
+  #       @invitee  = invitee
+  #
+  #       subject = "#{@inviter.name.familiar} added you to some new stuff in Basecamp (#{@account.name})"
+  #
+  #       mail \
+  #         subject:   subject,
+  #         to:        invitee.email_address,
+  #         from:      common_address(inviter),
+  #         reply_to:  inviter.email_address_with_name
+  #     end
+  #   end
+  #
+  #   InvitationsMailer.account_invitation(person_a, person_b).deliver_later
+  #
+  # Using parameterized mailers, this can be rewritten as:
+  #
+  #   class InvitationsMailer < ApplicationMailer
+  #     before_action { @inviter, @invitee = params[:inviter], params[:invitee] }
+  #     before_action { @account = params[:inviter].account }
+  #
+  #     default to:       -> { @invitee.email_address },
+  #             from:     -> { common_address(@inviter) },
+  #             reply_to: -> { @inviter.email_address_with_name }
+  #
+  #     def account_invitation
+  #       mail subject: "#{@inviter.name} invited you to their Basecamp (#{@account.name})"
+  #     end
+  #
+  #     def project_invitation
+  #       @project    = params[:project]
+  #       @summarizer = ProjectInvitationSummarizer.new(@project.bucket)
+  #
+  #       mail subject: "#{@inviter.name.familiar} added you to a project in Basecamp (#{@account.name})"
+  #     end
+  #
+  #     def bulk_project_invitation
+  #       @projects = params[:projects].sort_by(&:name)
+  #
+  #       mail subject: "#{@inviter.name.familiar} added you to some new stuff in Basecamp (#{@account.name})"
+  #     end
+  #   end
+  #
+  #   InvitationsMailer.with(inviter: person_a, invitee: person_b).account_invitation.deliver_later
+  module Parameterized
+    extend ActiveSupport::Concern
+
+    included do
+      attr_accessor :params
+    end
+
+    module ClassMethods
+      # Provide the parameters to the mailer in order to use them in the instance methods and callbacks.
+      #
+      #   InvitationsMailer.with(inviter: person_a, invitee: person_b).account_invitation.deliver_later
+      #
+      # See Parameterized documentation for full example.
+      def with(params)
+        ActionMailer::Parameterized::Mailer.new(self, params)
+      end
+    end
+
+    class Mailer # :nodoc:
+      def initialize(mailer, params)
+        @mailer, @params = mailer, params
+      end
+
+      private
+        def method_missing(method_name, *args)
+          if @mailer.action_methods.include?(method_name.to_s)
+            ActionMailer::Parameterized::MessageDelivery.new(@mailer, method_name, @params, *args)
+          else
+            super
+          end
+        end
+
+        def respond_to_missing?(method, include_all = false)
+          @mailer.respond_to?(method, include_all)
+        end
+    end
+
+    class MessageDelivery < ActionMailer::MessageDelivery # :nodoc:
+      def initialize(mailer_class, action, params, *args)
+        super(mailer_class, action, *args)
+        @params = params
+      end
+
+      private
+        def processed_mailer
+          @processed_mailer ||= @mailer_class.new.tap do |mailer|
+            mailer.params = @params
+            mailer.process @action, *@args
+          end
+        end
+
+        def enqueue_delivery(delivery_method, options = {})
+          if processed?
+            super
+          else
+            args = @mailer_class.name, @action.to_s, delivery_method.to_s, @params, *@args
+            ActionMailer::Parameterized::DeliveryJob.set(options).perform_later(*args)
+          end
+        end
+    end
+
+    class DeliveryJob < ActionMailer::DeliveryJob # :nodoc:
+      def perform(mailer, mail_method, delivery_method, params, *args)
+        mailer.constantize.with(params).public_send(mail_method, *args).send(delivery_method)
+      end
+    end
+  end
+end
diff --git a/actionmailer/lib/action_mailer/preview.rb b/actionmailer/lib/action_mailer/preview.rb
index aab92fe8db..0aea84fd2b 100644
--- a/actionmailer/lib/action_mailer/preview.rb
+++ b/actionmailer/lib/action_mailer/preview.rb
@@ -1,4 +1,6 @@
-require 'active_support/descendants_tracker'
+# frozen_string_literal: true
+
+require "active_support/descendants_tracker"
 
 module ActionMailer
   module Previews #:nodoc:
@@ -15,13 +17,12 @@ module ActionMailer
       #
       #     config.action_mailer.show_previews = true
       #
-      # Defaults to true for development environment
+      # Defaults to +true+ for development environment
       #
       mattr_accessor :show_previews, instance_writer: false
 
       # :nodoc:
-      mattr_accessor :preview_interceptors, instance_writer: false
-      self.preview_interceptors = [ActionMailer::InlinePreviewInterceptor]
+      mattr_accessor :preview_interceptors, instance_writer: false, default: [ActionMailer::InlinePreviewInterceptor]
     end
 
     module ClassMethods
@@ -32,9 +33,10 @@ module ActionMailer
 
       # Register an Interceptor which will be called before mail is previewed.
       # Either a class or a string can be passed in as the Interceptor. If a
-      # string is passed in it will be <tt>constantize</tt>d.
+      # string is passed in it will be constantized.
       def register_preview_interceptor(interceptor)
-        preview_interceptor = case interceptor
+        preview_interceptor = \
+          case interceptor
           when String, Symbol
             interceptor.to_s.camelize.constantize
           else
@@ -51,6 +53,12 @@ module ActionMailer
   class Preview
     extend ActiveSupport::DescendantsTracker
 
+    attr_reader :params
+
+    def initialize(params = {})
+      @params = params
+    end
+
     class << self
       # Returns all mailer preview classes.
       def all
@@ -61,8 +69,8 @@ module ActionMailer
       # Returns the mail object for the given email name. The registered preview
       # interceptors will be informed so that they can transform the message
       # as they would if the mail was actually being delivered.
-      def call(email)
-        preview = self.new
+      def call(email, params = {})
+        preview = new(params)
         message = preview.public_send(email)
         inform_preview_interceptors(message)
         message
@@ -73,42 +81,42 @@ module ActionMailer
         public_instance_methods(false).map(&:to_s).sort
       end
 
-      # Returns true if the email exists.
+      # Returns +true+ if the email exists.
       def email_exists?(email)
         emails.include?(email)
       end
 
-      # Returns true if the preview exists.
+      # Returns +true+ if the preview exists.
       def exists?(preview)
-        all.any?{ |p| p.preview_name == preview }
+        all.any? { |p| p.preview_name == preview }
       end
 
       # Find a mailer preview by its underscored class name.
       def find(preview)
-        all.find{ |p| p.preview_name == preview }
+        all.find { |p| p.preview_name == preview }
       end
 
       # Returns the underscored name of the mailer preview without the suffix.
       def preview_name
-        name.sub(/Preview$/, '').underscore
+        name.sub(/Preview$/, "").underscore
       end
 
-      protected
-        def load_previews #:nodoc:
+      private
+        def load_previews
           if preview_path
-            Dir["#{preview_path}/**/*_preview.rb"].each{ |file| require_dependency file }
+            Dir["#{preview_path}/**/*_preview.rb"].sort.each { |file| require_dependency file }
           end
         end
 
-        def preview_path #:nodoc:
+        def preview_path
           Base.preview_path
         end
 
-        def show_previews #:nodoc:
+        def show_previews
           Base.show_previews
         end
 
-        def inform_preview_interceptors(message) #:nodoc:
+        def inform_preview_interceptors(message)
           Base.preview_interceptors.each do |interceptor|
             interceptor.previewing_email(message)
           end
diff --git a/actionmailer/lib/action_mailer/railtie.rb b/actionmailer/lib/action_mailer/railtie.rb
index a727ed38e9..69578471b0 100644
--- a/actionmailer/lib/action_mailer/railtie.rb
+++ b/actionmailer/lib/action_mailer/railtie.rb
@@ -1,4 +1,6 @@
-require 'active_job/railtie'
+# frozen_string_literal: true
+
+require "active_job/railtie"
 require "action_mailer"
 require "rails"
 require "abstract_controller/railties/routes_helpers"
@@ -18,7 +20,7 @@ module ActionMailer
 
       if app.config.force_ssl
         options.default_url_options ||= {}
-        options.default_url_options[:protocol] ||= 'https'
+        options.default_url_options[:protocol] ||= "https"
       end
 
       options.assets_dir      ||= paths["public"].first
@@ -28,7 +30,7 @@ module ActionMailer
       options.cache_store ||= Rails.cache
 
       if options.show_previews
-        options.preview_path  ||= defined?(Rails.root) ? "#{Rails.root}/test/mailers/previews" : nil
+        options.preview_path ||= defined?(Rails.root) ? "#{Rails.root}/test/mailers/previews" : nil
       end
 
       # make sure readers methods get compiled
@@ -44,7 +46,7 @@ module ActionMailer
         register_preview_interceptors(options.delete(:preview_interceptors))
         register_observers(options.delete(:observers))
 
-        options.each { |k,v| send("#{k}=", v) }
+        options.each { |k, v| send("#{k}=", v) }
       end
 
       ActiveSupport.on_load(:action_dispatch_integration_test) { include ActionMailer::TestCase::ClearTestDeliveries }
@@ -56,13 +58,19 @@ module ActionMailer
       end
     end
 
+    initializer "action_mailer.eager_load_actions" do
+      ActiveSupport.on_load(:after_initialize) do
+        ActionMailer::Base.descendants.each(&:action_methods) if config.eager_load
+      end
+    end
+
     config.after_initialize do |app|
       options = app.config.action_mailer
 
       if options.show_previews
         app.routes.prepend do
-          get '/rails/mailers'         => "rails/mailers#index", internal: true
-          get '/rails/mailers/*path'   => "rails/mailers#preview", internal: true
+          get "/rails/mailers"         => "rails/mailers#index", internal: true
+          get "/rails/mailers/*path"   => "rails/mailers#preview", internal: true
         end
 
         if options.preview_path
diff --git a/actionmailer/lib/action_mailer/rescuable.rb b/actionmailer/lib/action_mailer/rescuable.rb
index f2eabfa057..5b567eb500 100644
--- a/actionmailer/lib/action_mailer/rescuable.rb
+++ b/actionmailer/lib/action_mailer/rescuable.rb
@@ -1,5 +1,7 @@
+# frozen_string_literal: true
+
 module ActionMailer #:nodoc:
-  # Provides `rescue_from` for mailers. Wraps mailer action processing,
+  # Provides +rescue_from+ for mailers. Wraps mailer action processing,
   # mail job processing, and mail delivery.
   module Rescuable
     extend ActiveSupport::Concern
diff --git a/actionmailer/lib/action_mailer/test_case.rb b/actionmailer/lib/action_mailer/test_case.rb
index b045e883ad..ee5a864847 100644
--- a/actionmailer/lib/action_mailer/test_case.rb
+++ b/actionmailer/lib/action_mailer/test_case.rb
@@ -1,11 +1,13 @@
-require 'active_support/test_case'
-require 'rails-dom-testing'
+# frozen_string_literal: true
+
+require "active_support/test_case"
+require "rails-dom-testing"
 
 module ActionMailer
   class NonInferrableMailerError < ::StandardError
     def initialize(name)
-      super "Unable to determine the mailer to test from #{name}. " +
-        "You'll need to specify it using tests YourMailer in your " +
+      super "Unable to determine the mailer to test from #{name}. " \
+        "You'll need to specify it using tests YourMailer in your " \
         "test case definition"
     end
   end
@@ -21,11 +23,11 @@ module ActionMailer
 
       private
 
-      def clear_test_deliveries
-        if ActionMailer::Base.delivery_method == :test
-          ActionMailer::Base.deliveries.clear
+        def clear_test_deliveries
+          if ActionMailer::Base.delivery_method == :test
+            ActionMailer::Base.deliveries.clear
+          end
         end
-      end
     end
 
     module Behavior
@@ -41,6 +43,7 @@ module ActionMailer
         setup :initialize_test_deliveries
         setup :set_expected_mail
         teardown :restore_test_deliveries
+        ActiveSupport.run_load_hooks(:action_mailer_test_case, self)
       end
 
       module ClassMethods
@@ -56,7 +59,7 @@ module ActionMailer
         end
 
         def mailer_class
-          if mailer = self._mailer_class
+          if mailer = _mailer_class
             mailer
           else
             tests determine_default_mailer(name)
@@ -72,38 +75,36 @@ module ActionMailer
         end
       end
 
-      protected
+      private
 
-        def initialize_test_deliveries # :nodoc:
+        def initialize_test_deliveries
           set_delivery_method :test
           @old_perform_deliveries = ActionMailer::Base.perform_deliveries
           ActionMailer::Base.perform_deliveries = true
           ActionMailer::Base.deliveries.clear
         end
 
-        def restore_test_deliveries # :nodoc:
+        def restore_test_deliveries
           restore_delivery_method
           ActionMailer::Base.perform_deliveries = @old_perform_deliveries
         end
 
-        def set_delivery_method(method) # :nodoc:
+        def set_delivery_method(method)
           @old_delivery_method = ActionMailer::Base.delivery_method
           ActionMailer::Base.delivery_method = method
         end
 
-        def restore_delivery_method # :nodoc:
+        def restore_delivery_method
           ActionMailer::Base.deliveries.clear
           ActionMailer::Base.delivery_method = @old_delivery_method
         end
 
-        def set_expected_mail # :nodoc:
+        def set_expected_mail
           @expected = Mail.new
           @expected.content_type ["text", "plain", { "charset" => charset }]
-          @expected.mime_version = '1.0'
+          @expected.mime_version = "1.0"
         end
 
-      private
-
         def charset
           "UTF-8"
         end
@@ -113,7 +114,7 @@ module ActionMailer
         end
 
         def read_fixture(action)
-          IO.readlines(File.join(Rails.root, 'test', 'fixtures', self.class.mailer_class.name.underscore, action))
+          IO.readlines(File.join(Rails.root, "test", "fixtures", self.class.mailer_class.name.underscore, action))
         end
     end
 
diff --git a/actionmailer/lib/action_mailer/test_helper.rb b/actionmailer/lib/action_mailer/test_helper.rb
index e423aac389..8ee4d06915 100644
--- a/actionmailer/lib/action_mailer/test_helper.rb
+++ b/actionmailer/lib/action_mailer/test_helper.rb
@@ -1,4 +1,6 @@
-require 'active_job'
+# frozen_string_literal: true
+
+require "active_job"
 
 module ActionMailer
   # Provides helper methods for testing Action Mailer, including #assert_emails
@@ -88,7 +90,49 @@ module ActionMailer
     #     end
     #   end
     def assert_enqueued_emails(number, &block)
-      assert_enqueued_jobs number, only: ActionMailer::DeliveryJob, &block
+      assert_enqueued_jobs number, only: [ ActionMailer::DeliveryJob, ActionMailer::Parameterized::DeliveryJob ], &block
+    end
+
+    # Asserts that a specific email has been enqueued, optionally
+    # matching arguments.
+    #
+    #   def test_email
+    #     ContactMailer.welcome.deliver_later
+    #     assert_enqueued_email_with ContactMailer, :welcome
+    #   end
+    #
+    #   def test_email_with_arguments
+    #     ContactMailer.welcome("Hello", "Goodbye").deliver_later
+    #     assert_enqueued_email_with ContactMailer, :welcome, args: ["Hello", "Goodbye"]
+    #   end
+    #
+    # If a block is passed, that block should cause the specified email
+    # to be enqueued.
+    #
+    #   def test_email_in_block
+    #     assert_enqueued_email_with ContactMailer, :welcome do
+    #       ContactMailer.welcome.deliver_later
+    #     end
+    #   end
+    #
+    # If `args` is provided as a Hash, a parameterized email is matched.
+    #
+    #   def test_parameterized_email
+    #     assert_enqueued_email_with ContactMailer, :welcome,
+    #       args: {email: 'user@example.com} do
+    #       ContactMailer.with(email: 'user@example.com').welcome.deliver_later
+    #     end
+    #   end
+    def assert_enqueued_email_with(mailer, method, args: nil, queue: "mailers", &block)
+      if args.is_a? Hash
+        job = ActionMailer::Parameterized::DeliveryJob
+        args = [mailer.to_s, method.to_s, "deliver_now", args]
+      else
+        job = ActionMailer::DeliveryJob
+        args = [mailer.to_s, method.to_s, "deliver_now", *args]
+      end
+
+      assert_enqueued_with(job: job, args: args, queue: queue, &block)
     end
 
     # Asserts that no emails are enqueued for later delivery.
@@ -107,7 +151,7 @@ module ActionMailer
     #     end
     #   end
     def assert_no_enqueued_emails(&block)
-      assert_no_enqueued_jobs only: ActionMailer::DeliveryJob, &block
+      assert_no_enqueued_jobs only: [ ActionMailer::DeliveryJob, ActionMailer::Parameterized::DeliveryJob ], &block
     end
   end
 end
diff --git a/actionmailer/lib/action_mailer/version.rb b/actionmailer/lib/action_mailer/version.rb
index 06f80a8fdc..4549d6eb57 100644
--- a/actionmailer/lib/action_mailer/version.rb
+++ b/actionmailer/lib/action_mailer/version.rb
@@ -1,4 +1,6 @@
-require_relative 'gem_version'
+# frozen_string_literal: true
+
+require_relative "gem_version"
 
 module ActionMailer
   # Returns the version of the currently loaded Action Mailer as a
diff --git a/actionmailer/lib/rails/generators/mailer/mailer_generator.rb b/actionmailer/lib/rails/generators/mailer/mailer_generator.rb
index 01bdfb0685..97eac30db1 100644
--- a/actionmailer/lib/rails/generators/mailer/mailer_generator.rb
+++ b/actionmailer/lib/rails/generators/mailer/mailer_generator.rb
@@ -1,36 +1,37 @@
+# frozen_string_literal: true
+
 module Rails
   module Generators
     class MailerGenerator < NamedBase
-      source_root File.expand_path("../templates", __FILE__)
+      source_root File.expand_path("templates", __dir__)
 
       argument :actions, type: :array, default: [], banner: "method method"
 
       check_class_collision suffix: "Mailer"
 
       def create_mailer_file
-        template "mailer.rb", File.join('app/mailers', class_path, "#{file_name}_mailer.rb")
+        template "mailer.rb", File.join("app/mailers", class_path, "#{file_name}_mailer.rb")
 
         in_root do
-          if self.behavior == :invoke && !File.exist?(application_mailer_file_name)
-            template 'application_mailer.rb', application_mailer_file_name
+          if behavior == :invoke && !File.exist?(application_mailer_file_name)
+            template "application_mailer.rb", application_mailer_file_name
           end
         end
       end
 
       hook_for :template_engine, :test_framework
 
-      protected
-        def file_name
-          @_file_name ||= super.gsub(/_mailer/i, '')
+      private
+        def file_name # :doc:
+          @_file_name ||= super.gsub(/_mailer/i, "")
         end
 
-      private
         def application_mailer_file_name
           @_application_mailer_file_name ||= if mountable_engine?
-                                             "app/mailers/#{namespaced_path}/application_mailer.rb"
-                                           else
-                                             "app/mailers/application_mailer.rb"
-                                           end
+            "app/mailers/#{namespaced_path}/application_mailer.rb"
+          else
+            "app/mailers/application_mailer.rb"
+          end
         end
     end
   end
diff --git a/actionmailer/lib/rails/generators/mailer/templates/application_mailer.rb b/actionmailer/lib/rails/generators/mailer/templates/application_mailer.rb.tt
index 00fb9bd48f..00fb9bd48f 100644
--- a/actionmailer/lib/rails/generators/mailer/templates/application_mailer.rb
+++ b/actionmailer/lib/rails/generators/mailer/templates/application_mailer.rb.tt
diff --git a/actionmailer/lib/rails/generators/mailer/templates/mailer.rb b/actionmailer/lib/rails/generators/mailer/templates/mailer.rb.tt
index 348d314758..348d314758 100644
--- a/actionmailer/lib/rails/generators/mailer/templates/mailer.rb
+++ b/actionmailer/lib/rails/generators/mailer/templates/mailer.rb.tt
diff --git a/actionmailer/test/abstract_unit.rb b/actionmailer/test/abstract_unit.rb
index 8d740ac863..45f69d5375 100644
--- a/actionmailer/test/abstract_unit.rb
+++ b/actionmailer/test/abstract_unit.rb
@@ -1,25 +1,27 @@
-require 'active_support/core_ext/kernel/reporting'
+# frozen_string_literal: true
+
+require "active_support/core_ext/kernel/reporting"
 
 # These are the normal settings that will be set up by Railties
 # TODO: Have these tests support other combinations of these values
 silence_warnings do
-  Encoding.default_internal = "UTF-8"
-  Encoding.default_external = "UTF-8"
+  Encoding.default_internal = Encoding::UTF_8
+  Encoding.default_external = Encoding::UTF_8
 end
 
 module Rails
   def self.root
-    File.expand_path('../', File.dirname(__FILE__))
+    File.expand_path("..", __dir__)
   end
 end
 
-require 'active_support/testing/autorun'
-require 'active_support/testing/method_call_assertions'
-require 'action_mailer'
-require 'action_mailer/test_case'
+require "active_support/testing/autorun"
+require "active_support/testing/method_call_assertions"
+require "action_mailer"
+require "action_mailer/test_case"
 
 # Emulate AV railtie
-require 'action_view'
+require "action_view"
 ActionMailer::Base.include(ActionView::Layouts)
 
 # Show backtraces for deprecated behavior for quicker cleanup.
@@ -28,18 +30,18 @@ ActiveSupport::Deprecation.debug = true
 # Disable available locale checks to avoid warnings running the test suite.
 I18n.enforce_available_locales = false
 
-FIXTURE_LOAD_PATH = File.expand_path('fixtures', File.dirname(__FILE__))
+FIXTURE_LOAD_PATH = File.expand_path("fixtures", __dir__)
 ActionMailer::Base.view_paths = FIXTURE_LOAD_PATH
 
-# Skips the current run on Rubinius using Minitest::Assertions#skip
-def rubinius_skip(message = '')
-  skip message if RUBY_ENGINE == 'rbx'
-end
-# Skips the current run on JRuby using Minitest::Assertions#skip
-def jruby_skip(message = '')
-  skip message if defined?(JRUBY_VERSION)
-end
-
 class ActiveSupport::TestCase
   include ActiveSupport::Testing::MethodCallAssertions
+
+  # Skips the current run on Rubinius using Minitest::Assertions#skip
+  private def rubinius_skip(message = "")
+    skip message if RUBY_ENGINE == "rbx"
+  end
+  # Skips the current run on JRuby using Minitest::Assertions#skip
+  private def jruby_skip(message = "")
+    skip message if defined?(JRUBY_VERSION)
+  end
 end
diff --git a/actionmailer/test/assert_select_email_test.rb b/actionmailer/test/assert_select_email_test.rb
index cae2e20abd..eb58ddd9c9 100644
--- a/actionmailer/test/assert_select_email_test.rb
+++ b/actionmailer/test/assert_select_email_test.rb
@@ -1,4 +1,6 @@
-require 'abstract_unit'
+# frozen_string_literal: true
+
+require "abstract_unit"
 
 class AssertSelectEmailTest < ActionMailer::TestCase
   class AssertSelectMailer < ActionMailer::Base
@@ -11,8 +13,8 @@ class AssertSelectEmailTest < ActionMailer::TestCase
   class AssertMultipartSelectMailer < ActionMailer::Base
     def test(options)
       mail subject: "Test e-mail", from: "test@test.host", to: "test <test@test.host>" do |format|
-        format.text { render text: options[:text] }
-        format.html { render text: options[:html] }
+        format.text { render plain: options[:text] }
+        format.html { render plain: options[:html] }
       end
     end
   end
@@ -36,7 +38,7 @@ class AssertSelectEmailTest < ActionMailer::TestCase
   end
 
   def test_assert_select_email_multipart
-    AssertMultipartSelectMailer.test(html: "<div><p>foo</p><p>bar</p></div>", text: 'foo bar').deliver_now
+    AssertMultipartSelectMailer.test(html: "<div><p>foo</p><p>bar</p></div>", text: "foo bar").deliver_now
     assert_select_email do
       assert_select "div:root" do
         assert_select "p:first-child", "foo"
diff --git a/actionmailer/test/asset_host_test.rb b/actionmailer/test/asset_host_test.rb
index 10cfdcf693..9cd8cae88c 100644
--- a/actionmailer/test/asset_host_test.rb
+++ b/actionmailer/test/asset_host_test.rb
@@ -1,11 +1,13 @@
-require 'abstract_unit'
-require 'action_controller'
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "action_controller"
 
 class AssetHostMailer < ActionMailer::Base
   def email_with_asset
-    mail to: 'test@localhost',
-      subject: 'testing email containing asset path while asset_host is set',
-      from: 'tester@example.com'
+    mail to: "test@localhost",
+      subject: "testing email containing asset path while asset_host is set",
+      from: "tester@example.com"
   end
 end
 
@@ -22,16 +24,16 @@ class AssetHostTest < ActionMailer::TestCase
 
   def test_asset_host_as_string
     mail = AssetHostMailer.email_with_asset
-    assert_dom_equal %Q{<img alt="Somelogo" src="http://www.example.com/images/somelogo.png" />}, mail.body.to_s.strip
+    assert_dom_equal '<img src="http://www.example.com/images/somelogo.png" />', mail.body.to_s.strip
   end
 
   def test_asset_host_as_one_argument_proc
     AssetHostMailer.config.asset_host = Proc.new { |source|
-      if source.starts_with?('/images')
-        'http://images.example.com'
+      if source.starts_with?("/images")
+        "http://images.example.com"
       end
     }
     mail = AssetHostMailer.email_with_asset
-    assert_dom_equal %Q{<img alt="Somelogo" src="http://images.example.com/images/somelogo.png" />}, mail.body.to_s.strip
+    assert_dom_equal '<img src="http://images.example.com/images/somelogo.png" />', mail.body.to_s.strip
   end
 end
diff --git a/actionmailer/test/base_test.rb b/actionmailer/test/base_test.rb
index 50f2c71737..977e0e201e 100644
--- a/actionmailer/test/base_test.rb
+++ b/actionmailer/test/base_test.rb
@@ -1,12 +1,14 @@
-require 'abstract_unit'
-require 'set'
+# frozen_string_literal: true
 
-require 'action_dispatch'
-require 'active_support/time'
+require "abstract_unit"
+require "set"
 
-require 'mailers/base_mailer'
-require 'mailers/proc_mailer'
-require 'mailers/asset_mailer'
+require "action_dispatch"
+require "active_support/time"
+
+require "mailers/base_mailer"
+require "mailers/proc_mailer"
+require "mailers/asset_mailer"
 
 class BaseTest < ActiveSupport::TestCase
   include Rails::Dom::Testing::Assertions::DomAssertions
@@ -32,33 +34,33 @@ class BaseTest < ActiveSupport::TestCase
   # Basic mail usage without block
   test "mail() should set the headers of the mail message" do
     email = BaseMailer.welcome
-    assert_equal(['system@test.lindsaar.net'],    email.to)
-    assert_equal(['jose@test.plataformatec.com'], email.from)
-    assert_equal('The first email on new API!',   email.subject)
+    assert_equal(["system@test.lindsaar.net"],    email.to)
+    assert_equal(["jose@test.plataformatec.com"], email.from)
+    assert_equal("The first email on new API!",   email.subject)
   end
 
   test "mail() with from overwrites the class level default" do
-    email = BaseMailer.welcome(from: 'someone@example.com',
-                               to:   'another@example.org')
-    assert_equal(['someone@example.com'], email.from)
-    assert_equal(['another@example.org'], email.to)
+    email = BaseMailer.welcome(from: "someone@example.com",
+                               to:   "another@example.org")
+    assert_equal(["someone@example.com"], email.from)
+    assert_equal(["another@example.org"], email.to)
   end
 
   test "mail() with bcc, cc, content_type, charset, mime_version, reply_to and date" do
     time  = Time.now.beginning_of_day.to_datetime
-    email = BaseMailer.welcome(bcc: 'bcc@test.lindsaar.net',
-                               cc: 'cc@test.lindsaar.net',
-                               content_type: 'multipart/mixed',
-                               charset: 'iso-8559-1',
-                               mime_version: '2.0',
-                               reply_to: 'reply-to@test.lindsaar.net',
+    email = BaseMailer.welcome(bcc: "bcc@test.lindsaar.net",
+                               cc: "cc@test.lindsaar.net",
+                               content_type: "multipart/mixed",
+                               charset: "iso-8559-1",
+                               mime_version: "2.0",
+                               reply_to: "reply-to@test.lindsaar.net",
                                date: time)
-    assert_equal(['bcc@test.lindsaar.net'],             email.bcc)
-    assert_equal(['cc@test.lindsaar.net'],              email.cc)
-    assert_equal('multipart/mixed; charset=iso-8559-1', email.content_type)
-    assert_equal('iso-8559-1',                          email.charset)
-    assert_equal('2.0',                                 email.mime_version)
-    assert_equal(['reply-to@test.lindsaar.net'],        email.reply_to)
+    assert_equal(["bcc@test.lindsaar.net"],             email.bcc)
+    assert_equal(["cc@test.lindsaar.net"],              email.cc)
+    assert_equal("multipart/mixed; charset=iso-8559-1", email.content_type)
+    assert_equal("iso-8559-1",                          email.charset)
+    assert_equal("2.0",                                 email.mime_version)
+    assert_equal(["reply-to@test.lindsaar.net"],        email.reply_to)
     assert_equal(time,                                  email.date)
   end
 
@@ -75,63 +77,63 @@ class BaseTest < ActiveSupport::TestCase
 
   test "should set template content type if mail has only one part" do
     mail = BaseMailer.html_only
-    assert_equal('text/html', mail.mime_type)
+    assert_equal("text/html", mail.mime_type)
     mail = BaseMailer.plain_text_only
-    assert_equal('text/plain', mail.mime_type)
+    assert_equal("text/plain", mail.mime_type)
   end
 
   # Custom headers
   test "custom headers" do
     email = BaseMailer.welcome
-    assert_equal("Not SPAM", email['X-SPAM'].decoded)
+    assert_equal("Not SPAM", email["X-SPAM"].decoded)
   end
 
   test "can pass random headers in as a hash to mail" do
-    hash = {'X-Special-Domain-Specific-Header' => "SecretValue",
-            'In-Reply-To' => '1234@mikel.me.com' }
+    hash = { "X-Special-Domain-Specific-Header" => "SecretValue",
+            "In-Reply-To" => "1234@mikel.me.com" }
     mail = BaseMailer.welcome(hash)
-    assert_equal('SecretValue', mail['X-Special-Domain-Specific-Header'].decoded)
-    assert_equal('1234@mikel.me.com', mail['In-Reply-To'].decoded)
+    assert_equal("SecretValue", mail["X-Special-Domain-Specific-Header"].decoded)
+    assert_equal("1234@mikel.me.com", mail["In-Reply-To"].decoded)
   end
 
   test "can pass random headers in as a hash to headers" do
-    hash = {'X-Special-Domain-Specific-Header' => "SecretValue",
-            'In-Reply-To' => '1234@mikel.me.com' }
+    hash = { "X-Special-Domain-Specific-Header" => "SecretValue",
+            "In-Reply-To" => "1234@mikel.me.com" }
     mail = BaseMailer.welcome_with_headers(hash)
-    assert_equal('SecretValue', mail['X-Special-Domain-Specific-Header'].decoded)
-    assert_equal('1234@mikel.me.com', mail['In-Reply-To'].decoded)
+    assert_equal("SecretValue", mail["X-Special-Domain-Specific-Header"].decoded)
+    assert_equal("1234@mikel.me.com", mail["In-Reply-To"].decoded)
   end
 
   # Attachments
   test "attachment with content" do
     email = BaseMailer.attachment_with_content
     assert_equal(1, email.attachments.length)
-    assert_equal('invoice.pdf', email.attachments[0].filename)
-    assert_equal('This is test File content', email.attachments['invoice.pdf'].decoded)
+    assert_equal("invoice.pdf", email.attachments[0].filename)
+    assert_equal("This is test File content", email.attachments["invoice.pdf"].decoded)
   end
 
   test "attachment gets content type from filename" do
     email = BaseMailer.attachment_with_content
-    assert_equal('invoice.pdf', email.attachments[0].filename)
-    assert_equal('application/pdf', email.attachments[0].mime_type)
+    assert_equal("invoice.pdf", email.attachments[0].filename)
+    assert_equal("application/pdf", email.attachments[0].mime_type)
   end
 
   test "attachment with hash" do
     email = BaseMailer.attachment_with_hash
     assert_equal(1, email.attachments.length)
-    assert_equal('invoice.jpg', email.attachments[0].filename)
-    expected = "\312\213\254\232)b"
+    assert_equal("invoice.jpg", email.attachments[0].filename)
+    expected = "\312\213\254\232)b".dup
     expected.force_encoding(Encoding::BINARY)
-    assert_equal expected, email.attachments['invoice.jpg'].decoded
+    assert_equal expected, email.attachments["invoice.jpg"].decoded
   end
 
   test "attachment with hash using default mail encoding" do
     email = BaseMailer.attachment_with_hash_default_encoding
     assert_equal(1, email.attachments.length)
-    assert_equal('invoice.jpg', email.attachments[0].filename)
-    expected = "\312\213\254\232)b"
+    assert_equal("invoice.jpg", email.attachments[0].filename)
+    expected = "\312\213\254\232)b".dup
     expected.force_encoding(Encoding::BINARY)
-    assert_equal expected, email.attachments['invoice.jpg'].decoded
+    assert_equal expected, email.attachments["invoice.jpg"].decoded
   end
 
   test "sets mime type to multipart/mixed when attachment is included" do
@@ -140,6 +142,11 @@ class BaseTest < ActiveSupport::TestCase
     assert_equal("multipart/mixed", email.mime_type)
   end
 
+  test "set mime type to text/html when attachment is included and body is set" do
+    email = BaseMailer.attachment_with_content(body: "Hello there", content_type: "text/html")
+    assert_equal("text/html", email.mime_type)
+  end
+
   test "adds the rendered template as part" do
     email = BaseMailer.attachment_with_content
     assert_equal(2, email.parts.length)
@@ -215,24 +222,24 @@ class BaseTest < ActiveSupport::TestCase
       email = BaseMailer.welcome(subject: nil)
       assert_equal "Welcome", email.subject
 
-      with_translation 'en', base_mailer: {welcome: {subject: "New Subject!"}} do
+      with_translation "en", base_mailer: { welcome: { subject: "New Subject!" } } do
         email = BaseMailer.welcome(subject: nil)
         assert_equal "New Subject!", email.subject
       end
     end
   end
 
-  test 'default subject can have interpolations' do
-    with_translation 'en', base_mailer: {with_subject_interpolations: {subject: 'Will the real %{rapper_or_impersonator} please stand up?'}} do
+  test "default subject can have interpolations" do
+    with_translation "en", base_mailer: { with_subject_interpolations: { subject: "Will the real %{rapper_or_impersonator} please stand up?" } } do
       email = BaseMailer.with_subject_interpolations
-      assert_equal 'Will the real Slim Shady please stand up?', email.subject
+      assert_equal "Will the real Slim Shady please stand up?", email.subject
     end
   end
 
   test "translations are scoped properly" do
-    with_translation 'en', base_mailer: {email_with_translations: {greet_user: "Hello %{name}!"}} do
+    with_translation "en", base_mailer: { email_with_translations: { greet_user: "Hello %{name}!" } } do
       email = BaseMailer.email_with_translations
-      assert_equal 'Hello lifo!', email.body.encoded
+      assert_equal "Hello lifo!", email.body.encoded
     end
   end
 
@@ -240,7 +247,7 @@ class BaseTest < ActiveSupport::TestCase
     class LateAttachmentMailer < ActionMailer::Base
       def welcome
         mail body: "yay", from: "welcome@example.com", to: "to@example.com"
-        attachments['invoice.pdf'] = 'This is test File content'
+        attachments["invoice.pdf"] = "This is test File content"
       end
     end
 
@@ -252,7 +259,7 @@ class BaseTest < ActiveSupport::TestCase
     class LateInlineAttachmentMailer < ActionMailer::Base
       def welcome
         mail body: "yay", from: "welcome@example.com", to: "to@example.com"
-        attachments.inline['invoice.pdf'] = 'This is test File content'
+        attachments.inline["invoice.pdf"] = "This is test File content"
       end
     end
 
@@ -271,13 +278,13 @@ class BaseTest < ActiveSupport::TestCase
     assert_nothing_raised { mail.message }
 
     assert_equal ["image/jpeg; filename=controller_attachments.jpg",
-                  "image/jpeg; filename=attachments.jpg"], mail.attachments.inline.map {|a| a['Content-Type'].to_s }
+                  "image/jpeg; filename=attachments.jpg"], mail.attachments.inline.map { |a| a["Content-Type"].to_s }
   end
 
   test "accessing attachments works after mail was called" do
     class LateAttachmentAccessorMailer < ActionMailer::Base
       def welcome
-        attachments['invoice.pdf'] = 'This is test File content'
+        attachments["invoice.pdf"] = "This is test File content"
         mail body: "yay", from: "welcome@example.com", to: "to@example.com"
 
         unless attachments.map(&:filename) == ["invoice.pdf"]
@@ -315,22 +322,21 @@ class BaseTest < ActiveSupport::TestCase
 
   test "implicit multipart with attachments creates nested parts" do
     email = BaseMailer.implicit_multipart(attachments: true)
-    assert_equal("application/pdf", email.parts[0].mime_type)
-    assert_equal("multipart/alternative", email.parts[1].mime_type)
-    assert_equal("text/plain", email.parts[1].parts[0].mime_type)
-    assert_equal("TEXT Implicit Multipart", email.parts[1].parts[0].body.encoded)
-    assert_equal("text/html", email.parts[1].parts[1].mime_type)
-    assert_equal("HTML Implicit Multipart", email.parts[1].parts[1].body.encoded)
+    assert_equal(%w[ application/pdf multipart/alternative ], email.parts.map(&:mime_type).sort)
+    multipart = email.parts.detect { |p| p.mime_type == "multipart/alternative" }
+    assert_equal("text/plain", multipart.parts[0].mime_type)
+    assert_equal("TEXT Implicit Multipart", multipart.parts[0].body.encoded)
+    assert_equal("text/html", multipart.parts[1].mime_type)
+    assert_equal("HTML Implicit Multipart", multipart.parts[1].body.encoded)
   end
 
   test "implicit multipart with attachments and sort order" do
     order = ["text/html", "text/plain"]
     with_default BaseMailer, parts_order: order do
       email = BaseMailer.implicit_multipart(attachments: true)
-      assert_equal("application/pdf", email.parts[0].mime_type)
-      assert_equal("multipart/alternative", email.parts[1].mime_type)
-      assert_equal("text/plain", email.parts[1].parts[1].mime_type)
-      assert_equal("text/html", email.parts[1].parts[0].mime_type)
+      assert_equal(%w[ application/pdf multipart/alternative ], email.parts.map(&:mime_type).sort)
+      multipart = email.parts.detect { |p| p.mime_type == "multipart/alternative" }
+      assert_equal(%w[ text/html text/plain ], multipart.parts.map(&:mime_type).sort)
     end
   end
 
@@ -366,7 +372,7 @@ class BaseTest < ActiveSupport::TestCase
       I18n.backend = fallback_backend.new
       I18n.fallbacks[:"de-AT"] = [:de]
 
-      swap I18n, locale: 'de-AT' do
+      swap I18n, locale: "de-AT" do
         email = BaseMailer.implicit_with_locale
         assert_equal(2, email.parts.size)
         assert_equal("multipart/alternative", email.mime_type)
@@ -380,7 +386,6 @@ class BaseTest < ActiveSupport::TestCase
     end
   end
 
-
   test "implicit multipart with several view paths uses the first one with template" do
     old = BaseMailer.view_paths
     begin
@@ -421,12 +426,12 @@ class BaseTest < ActiveSupport::TestCase
 
   test "explicit multipart with attachments creates nested parts" do
     email = BaseMailer.explicit_multipart(attachments: true)
-    assert_equal("application/pdf", email.parts[0].mime_type)
-    assert_equal("multipart/alternative", email.parts[1].mime_type)
-    assert_equal("text/plain", email.parts[1].parts[0].mime_type)
-    assert_equal("TEXT Explicit Multipart", email.parts[1].parts[0].body.encoded)
-    assert_equal("text/html", email.parts[1].parts[1].mime_type)
-    assert_equal("HTML Explicit Multipart", email.parts[1].parts[1].body.encoded)
+    assert_equal(%w[ application/pdf multipart/alternative ], email.parts.map(&:mime_type).sort)
+    multipart = email.parts.detect { |p| p.mime_type == "multipart/alternative" }
+    assert_equal("text/plain", multipart.parts[0].mime_type)
+    assert_equal("TEXT Explicit Multipart", multipart.parts[0].body.encoded)
+    assert_equal("text/html", multipart.parts[1].mime_type)
+    assert_equal("HTML Explicit Multipart", multipart.parts[1].body.encoded)
   end
 
   test "explicit multipart with templates" do
@@ -449,7 +454,7 @@ class BaseTest < ActiveSupport::TestCase
     assert_equal("Format with any!", email.parts[1].body.encoded)
   end
 
-  test 'explicit without specifying format with format.any' do
+  test "explicit without specifying format with format.any" do
     error = assert_raises(ArgumentError) do
       BaseMailer.explicit_without_specifying_format_with_any.parts
     end
@@ -508,13 +513,13 @@ class BaseTest < ActiveSupport::TestCase
   test "calling just the action should return the generated mail object" do
     email = BaseMailer.welcome
     assert_equal(0, BaseMailer.deliveries.length)
-    assert_equal('The first email on new API!', email.subject)
+    assert_equal("The first email on new API!", email.subject)
   end
 
   test "calling deliver on the action should deliver the mail object" do
     assert_called(BaseMailer, :deliver_mail) do
       mail = BaseMailer.welcome.deliver_now
-      assert_equal 'The first email on new API!', mail.subject
+      assert_equal "The first email on new API!", mail.subject
     end
   end
 
@@ -534,35 +539,35 @@ class BaseTest < ActiveSupport::TestCase
 
   # Rendering
   test "you can specify a different template for implicit render" do
-    mail = BaseMailer.implicit_different_template('implicit_multipart').deliver_now
+    mail = BaseMailer.implicit_different_template("implicit_multipart").deliver_now
     assert_equal("HTML Implicit Multipart", mail.html_part.body.decoded)
     assert_equal("TEXT Implicit Multipart", mail.text_part.body.decoded)
   end
 
   test "should raise if missing template in implicit render" do
     assert_raises ActionView::MissingTemplate do
-      BaseMailer.implicit_different_template('missing_template').deliver_now
+      BaseMailer.implicit_different_template("missing_template").deliver_now
     end
     assert_equal(0, BaseMailer.deliveries.length)
   end
 
   test "you can specify a different template for explicit render" do
-    mail = BaseMailer.explicit_different_template('explicit_multipart_templates').deliver_now
+    mail = BaseMailer.explicit_different_template("explicit_multipart_templates").deliver_now
     assert_equal("HTML Explicit Multipart Templates", mail.html_part.body.decoded)
     assert_equal("TEXT Explicit Multipart Templates", mail.text_part.body.decoded)
   end
 
   test "you can specify a different layout" do
-    mail = BaseMailer.different_layout('different_layout').deliver_now
+    mail = BaseMailer.different_layout("different_layout").deliver_now
     assert_equal("HTML -- HTML", mail.html_part.body.decoded)
     assert_equal("PLAIN -- PLAIN", mail.text_part.body.decoded)
   end
 
   test "you can specify the template path for implicit lookup" do
-    mail = BaseMailer.welcome_from_another_path('another.path/base_mailer').deliver_now
+    mail = BaseMailer.welcome_from_another_path("another.path/base_mailer").deliver_now
     assert_equal("Welcome from another path", mail.body.encoded)
 
-    mail = BaseMailer.welcome_from_another_path(['unknown/invalid', 'another.path/base_mailer']).deliver_now
+    mail = BaseMailer.welcome_from_another_path(["unknown/invalid", "another.path/base_mailer"]).deliver_now
     assert_equal("Welcome from another path", mail.body.encoded)
   end
 
@@ -572,7 +577,7 @@ class BaseTest < ActiveSupport::TestCase
 
     mail = AssetMailer.welcome
 
-    assert_dom_equal(%{<img alt="Dummy" src="http://global.com/images/dummy.png" />}, mail.body.to_s.strip)
+    assert_dom_equal(%{<img src="http://global.com/images/dummy.png" />}, mail.body.to_s.strip)
   end
 
   test "assets tags should use a Mailer's asset_host settings when available" do
@@ -586,18 +591,18 @@ class BaseTest < ActiveSupport::TestCase
 
     mail = TempAssetMailer.welcome
 
-    assert_dom_equal(%{<img alt="Dummy" src="http://local.com/images/dummy.png" />}, mail.body.to_s.strip)
+    assert_dom_equal(%{<img src="http://local.com/images/dummy.png" />}, mail.body.to_s.strip)
   end
 
-  test 'the view is not rendered when mail was never called' do
+  test "the view is not rendered when mail was never called" do
     mail = BaseMailer.without_mail_call
-    assert_equal('', mail.body.to_s.strip)
+    assert_equal("", mail.body.to_s.strip)
     mail.deliver_now
   end
 
-  test 'the return value of mailer methods is not relevant' do
+  test "the return value of mailer methods is not relevant" do
     mail = BaseMailer.with_nil_as_return_value
-    assert_equal('Welcome', mail.body.to_s.strip)
+    assert_equal("Welcome", mail.body.to_s.strip)
     mail.deliver_now
   end
 
@@ -708,16 +713,16 @@ class BaseTest < ActiveSupport::TestCase
   end
 
   test "being able to put proc's into the defaults hash and they get evaluated on mail sending" do
-    mail1 = ProcMailer.welcome['X-Proc-Method']
+    mail1 = ProcMailer.welcome["X-Proc-Method"]
     yesterday = 1.day.ago
     Time.stub(:now, yesterday) do
-      mail2 = ProcMailer.welcome['X-Proc-Method']
+      mail2 = ProcMailer.welcome["X-Proc-Method"]
       assert(mail1.to_s.to_i > mail2.to_s.to_i)
     end
   end
 
-  test 'default values which have to_proc (e.g. symbols) should not be considered procs' do
-    assert(ProcMailer.welcome['x-has-to-proc'].to_s == 'symbol')
+  test "default values which have to_proc (e.g. symbols) should not be considered procs" do
+    assert(ProcMailer.welcome["x-has-to-proc"].to_s == "symbol")
   end
 
   test "we can call other defined methods on the class as needed" do
@@ -732,12 +737,12 @@ class BaseTest < ActiveSupport::TestCase
       def welcome ; mail ; end
 
       private
-      def add_special_header!
-        headers('X-Special-Header' => 'Wow, so special')
-      end
+        def add_special_header!
+          headers("X-Special-Header" => "Wow, so special")
+        end
     end
 
-    assert_equal('Wow, so special', BeforeActionMailer.welcome['X-Special-Header'].to_s)
+    assert_equal("Wow, so special", BeforeActionMailer.welcome["X-Special-Header"].to_s)
   end
 
   test "modifying the mail message with an after_action" do
@@ -747,12 +752,12 @@ class BaseTest < ActiveSupport::TestCase
       def welcome ; mail ; end
 
       private
-      def add_special_header!
-        headers('X-Special-Header' => 'Testing')
-      end
+        def add_special_header!
+          headers("X-Special-Header" => "Testing")
+        end
     end
 
-    assert_equal('Testing', AfterActionMailer.welcome['X-Special-Header'].to_s)
+    assert_equal("Testing", AfterActionMailer.welcome["X-Special-Header"].to_s)
   end
 
   test "adding an inline attachment using a before_action" do
@@ -762,19 +767,19 @@ class BaseTest < ActiveSupport::TestCase
       def welcome ; mail ; end
 
       private
-      def add_inline_attachment!
-        attachments.inline["footer.jpg"] = 'hey there'
-      end
+        def add_inline_attachment!
+          attachments.inline["footer.jpg"] = "hey there"
+        end
     end
 
     mail = DefaultInlineAttachmentMailer.welcome
-    assert_equal('image/jpeg; filename=footer.jpg', mail.attachments.inline.first['Content-Type'].to_s)
+    assert_equal("image/jpeg; filename=footer.jpg", mail.attachments.inline.first["Content-Type"].to_s)
   end
 
   test "action methods should be refreshed after defining new method" do
     class FooMailer < ActionMailer::Base
-      # this triggers action_methods
-      self.respond_to?(:foo)
+      # This triggers action_methods.
+      respond_to?(:foo)
 
       def notify
       end
@@ -798,8 +803,8 @@ class BaseTest < ActiveSupport::TestCase
 
   test "default_from can be set" do
     class DefaultFromMailer < ActionMailer::Base
-      default to: 'system@test.lindsaar.net'
-      self.default_options = {from: "robert.pankowecki@gmail.com"}
+      default to: "system@test.lindsaar.net"
+      self.default_options = { from: "robert.pankowecki@gmail.com" }
 
       def welcome
         mail(subject: "subject", body: "hello world")
@@ -814,7 +819,7 @@ class BaseTest < ActiveSupport::TestCase
       after_action :a_callback
 
       def welcome
-        headers('X-Special-Header' => 'special indeed!')
+        headers("X-Special-Header" => "special indeed!")
         mail subject: "subject", body: "hello world", to: ["joe@example.com"]
       end
 
@@ -830,7 +835,26 @@ class BaseTest < ActiveSupport::TestCase
     assert_equal "special indeed!", mail["X-Special-Header"].to_s
   end
 
-  protected
+  test "notification for process" do
+    begin
+      events = []
+      ActiveSupport::Notifications.subscribe("process.action_mailer") do |*args|
+        events << ActiveSupport::Notifications::Event.new(*args)
+      end
+
+      BaseMailer.welcome(body: "Hello there").deliver_now
+
+      assert_equal 1, events.length
+      assert_equal "process.action_mailer", events[0].name
+      assert_equal "BaseMailer", events[0].payload[:mailer]
+      assert_equal :welcome, events[0].payload[:action]
+      assert_equal [{ body: "Hello there" }], events[0].payload[:args]
+    ensure
+      ActiveSupport::Notifications.unsubscribe "process.action_mailer"
+    end
+  end
+
+  private
 
     # Execute the block setting the given values and restoring old values after
     # the block is executed.
@@ -945,3 +969,18 @@ class BasePreviewInterceptorsTest < ActiveSupport::TestCase
     end
   end
 end
+
+class BasePreviewTest < ActiveSupport::TestCase
+  class BaseMailerPreview < ActionMailer::Preview
+    def welcome
+      BaseMailer.welcome(params)
+    end
+  end
+
+  test "has access to params" do
+    params = { name: "World" }
+
+    message = BaseMailerPreview.call(:welcome, params)
+    assert_equal "World", message["name"].decoded
+  end
+end
diff --git a/actionmailer/test/caching_test.rb b/actionmailer/test/caching_test.rb
index 22e1bdb5f1..ae4e7bf57e 100644
--- a/actionmailer/test/caching_test.rb
+++ b/actionmailer/test/caching_test.rb
@@ -1,11 +1,13 @@
-require 'fileutils'
-require 'abstract_unit'
-require 'mailers/base_mailer'
-require 'mailers/caching_mailer'
+# frozen_string_literal: true
 
-CACHE_DIR = 'test_cache'
+require "fileutils"
+require "abstract_unit"
+require "mailers/base_mailer"
+require "mailers/caching_mailer"
+
+CACHE_DIR = "test_cache"
 # Don't change '/../temp/' cavalierly or you might hose something you don't want hosed
-FILE_STORE_PATH = File.join(File.dirname(__FILE__), '/../temp/', CACHE_DIR)
+FILE_STORE_PATH = File.join(__dir__, "/../temp/", CACHE_DIR)
 
 class FragmentCachingMailer < ActionMailer::Base
   abstract!
@@ -21,91 +23,87 @@ class BaseCachingTest < ActiveSupport::TestCase
     @mailer.perform_caching = true
     @mailer.cache_store = @store
   end
-
-  def test_fragment_cache_key
-    assert_equal 'views/what a key', @mailer.fragment_cache_key('what a key')
-  end
 end
 
 class FragmentCachingTest < BaseCachingTest
   def test_read_fragment_with_caching_enabled
-    @store.write('views/name', 'value')
-    assert_equal 'value', @mailer.read_fragment('name')
+    @store.write("views/name", "value")
+    assert_equal "value", @mailer.read_fragment("name")
   end
 
   def test_read_fragment_with_caching_disabled
     @mailer.perform_caching = false
-    @store.write('views/name', 'value')
-    assert_nil @mailer.read_fragment('name')
+    @store.write("views/name", "value")
+    assert_nil @mailer.read_fragment("name")
   end
 
   def test_fragment_exist_with_caching_enabled
-    @store.write('views/name', 'value')
-    assert @mailer.fragment_exist?('name')
-    assert !@mailer.fragment_exist?('other_name')
+    @store.write("views/name", "value")
+    assert @mailer.fragment_exist?("name")
+    assert !@mailer.fragment_exist?("other_name")
   end
 
   def test_fragment_exist_with_caching_disabled
     @mailer.perform_caching = false
-    @store.write('views/name', 'value')
-    assert !@mailer.fragment_exist?('name')
-    assert !@mailer.fragment_exist?('other_name')
+    @store.write("views/name", "value")
+    assert !@mailer.fragment_exist?("name")
+    assert !@mailer.fragment_exist?("other_name")
   end
 
   def test_write_fragment_with_caching_enabled
-    assert_nil @store.read('views/name')
-    assert_equal 'value', @mailer.write_fragment('name', 'value')
-    assert_equal 'value', @store.read('views/name')
+    assert_nil @store.read("views/name")
+    assert_equal "value", @mailer.write_fragment("name", "value")
+    assert_equal "value", @store.read("views/name")
   end
 
   def test_write_fragment_with_caching_disabled
-    assert_nil @store.read('views/name')
+    assert_nil @store.read("views/name")
     @mailer.perform_caching = false
-    assert_equal 'value', @mailer.write_fragment('name', 'value')
-    assert_nil @store.read('views/name')
+    assert_equal "value", @mailer.write_fragment("name", "value")
+    assert_nil @store.read("views/name")
   end
 
   def test_expire_fragment_with_simple_key
-    @store.write('views/name', 'value')
-    @mailer.expire_fragment 'name'
-    assert_nil @store.read('views/name')
+    @store.write("views/name", "value")
+    @mailer.expire_fragment "name"
+    assert_nil @store.read("views/name")
   end
 
   def test_expire_fragment_with_regexp
-    @store.write('views/name', 'value')
-    @store.write('views/another_name', 'another_value')
-    @store.write('views/primalgrasp', 'will not expire ;-)')
+    @store.write("views/name", "value")
+    @store.write("views/another_name", "another_value")
+    @store.write("views/primalgrasp", "will not expire ;-)")
 
     @mailer.expire_fragment(/name/)
 
-    assert_nil @store.read('views/name')
-    assert_nil @store.read('views/another_name')
-    assert_equal 'will not expire ;-)', @store.read('views/primalgrasp')
+    assert_nil @store.read("views/name")
+    assert_nil @store.read("views/another_name")
+    assert_equal "will not expire ;-)", @store.read("views/primalgrasp")
   end
 
   def test_fragment_for
-    @store.write('views/expensive', 'fragment content')
+    @store.write("views/expensive", "fragment content")
     fragment_computed = false
 
     view_context = @mailer.view_context
 
-    buffer = 'generated till now -> '.html_safe
-    buffer << view_context.send(:fragment_for, 'expensive') { fragment_computed = true }
+    buffer = "generated till now -> ".html_safe
+    buffer << view_context.send(:fragment_for, "expensive") { fragment_computed = true }
 
     assert !fragment_computed
-    assert_equal 'generated till now -> fragment content', buffer
+    assert_equal "generated till now -> fragment content", buffer
   end
 
   def test_html_safety
-    assert_nil @store.read('views/name')
-    content = 'value'.html_safe
-    assert_equal content, @mailer.write_fragment('name', content)
+    assert_nil @store.read("views/name")
+    content = "value".html_safe
+    assert_equal content, @mailer.write_fragment("name", content)
 
-    cached = @store.read('views/name')
+    cached = @store.read("views/name")
     assert_equal content, cached
     assert_equal String, cached.class
 
-    html_safe = @mailer.read_fragment('name')
+    html_safe = @mailer.read_fragment("name")
     assert_equal content, html_safe
     assert html_safe.html_safe?
   end
@@ -126,16 +124,16 @@ class FunctionalFragmentCachingTest < BaseCachingTest
 
     assert_match expected_body, email.body.encoded
     assert_match expected_body,
-      @store.read("views/caching/#{template_digest("caching_mailer/fragment_cache")}")
+      @store.read("views/caching_mailer/fragment_cache:#{template_digest("caching_mailer/fragment_cache")}/caching")
   end
 
   def test_fragment_caching_in_partials
     email = @mailer.fragment_cache_in_partials
-    expected_body = 'Old fragment caching in a partial'
+    expected_body = "Old fragment caching in a partial"
     assert_match(expected_body, email.body.encoded)
 
     assert_match(expected_body,
-      @store.read("views/caching/#{template_digest("caching_mailer/_partial")}"))
+      @store.read("views/caching_mailer/_partial:#{template_digest("caching_mailer/_partial")}/caching"))
   end
 
   def test_skip_fragment_cache_digesting
@@ -172,6 +170,7 @@ class FunctionalFragmentCachingTest < BaseCachingTest
   end
 
   def test_fragment_cache_instrumentation
+    @mailer.enable_fragment_cache_logging = true
     payload = nil
 
     subscriber = proc do |*args|
@@ -184,7 +183,9 @@ class FunctionalFragmentCachingTest < BaseCachingTest
     end
 
     assert_equal "caching_mailer", payload[:mailer]
-    assert_equal "views/caching/#{template_digest("caching_mailer/fragment_cache")}", payload[:key]
+    assert_equal [ :views, "caching_mailer/fragment_cache:#{template_digest("caching_mailer/fragment_cache")}", :caching ], payload[:key]
+  ensure
+    @mailer.enable_fragment_cache_logging = true
   end
 
   private
@@ -195,10 +196,9 @@ class FunctionalFragmentCachingTest < BaseCachingTest
 end
 
 class CacheHelperOutputBufferTest < BaseCachingTest
-
   class MockController
     def read_fragment(name, options)
-      return false
+      false
     end
 
     def write_fragment(name, fragment, options)
@@ -214,9 +214,9 @@ class CacheHelperOutputBufferTest < BaseCachingTest
     output_buffer = ActionView::OutputBuffer.new
     controller = MockController.new
     cache_helper = Class.new do
-      def self.controller; end;
-      def self.output_buffer; end;
-      def self.output_buffer=; end;
+      def self.controller; end
+      def self.output_buffer; end
+      def self.output_buffer=; end
     end
     cache_helper.extend(ActionView::Helpers::CacheHelper)
 
@@ -224,7 +224,7 @@ class CacheHelperOutputBufferTest < BaseCachingTest
       cache_helper.stub :output_buffer, output_buffer do
         assert_called_with cache_helper, :output_buffer=, [output_buffer.class.new(output_buffer)] do
           assert_nothing_raised do
-            cache_helper.send :fragment_for, 'Test fragment name', 'Test fragment', &Proc.new{ nil }
+            cache_helper.send :fragment_for, "Test fragment name", "Test fragment", &Proc.new { nil }
           end
         end
       end
@@ -235,9 +235,9 @@ class CacheHelperOutputBufferTest < BaseCachingTest
     output_buffer = ActiveSupport::SafeBuffer.new
     controller = MockController.new
     cache_helper = Class.new do
-      def self.controller; end;
-      def self.output_buffer; end;
-      def self.output_buffer=; end;
+      def self.controller; end
+      def self.output_buffer; end
+      def self.output_buffer=; end
     end
     cache_helper.extend(ActionView::Helpers::CacheHelper)
 
@@ -245,7 +245,7 @@ class CacheHelperOutputBufferTest < BaseCachingTest
       cache_helper.stub :output_buffer, output_buffer do
         assert_called_with cache_helper, :output_buffer=, [output_buffer.class.new(output_buffer)] do
           assert_nothing_raised do
-            cache_helper.send :fragment_for, 'Test fragment name', 'Test fragment', &Proc.new{ nil }
+            cache_helper.send :fragment_for, "Test fragment name", "Test fragment", &Proc.new { nil }
           end
         end
       end
diff --git a/actionmailer/test/delivery_methods_test.rb b/actionmailer/test/delivery_methods_test.rb
index bcbd036f26..025f7152bb 100644
--- a/actionmailer/test/delivery_methods_test.rb
+++ b/actionmailer/test/delivery_methods_test.rb
@@ -1,4 +1,6 @@
-require 'abstract_unit'
+# frozen_string_literal: true
+
+require "abstract_unit"
 
 class MyCustomDelivery
 end
@@ -23,7 +25,7 @@ class DefaultsDeliveryMethodsTest < ActiveSupport::TestCase
   test "default smtp settings" do
     settings = { address:              "localhost",
                  port:                 25,
-                 domain:               'localhost.localdomain',
+                 domain:               "localhost.localdomain",
                  user_name:            nil,
                  password:             nil,
                  authentication:       nil,
@@ -32,14 +34,14 @@ class DefaultsDeliveryMethodsTest < ActiveSupport::TestCase
   end
 
   test "default file delivery settings (with Rails.root)" do
-    settings = {location: "#{Rails.root}/tmp/mails"}
+    settings = { location: "#{Rails.root}/tmp/mails" }
     assert_equal settings, ActionMailer::Base.file_settings
   end
 
   test "default sendmail settings" do
     settings = {
-      location:  '/usr/sbin/sendmail',
-      arguments: '-i'
+      location:  "/usr/sbin/sendmail",
+      arguments: "-i"
     }
     assert_equal settings, ActionMailer::Base.sendmail_settings
   end
@@ -83,11 +85,11 @@ end
 class MailDeliveryTest < ActiveSupport::TestCase
   class DeliveryMailer < ActionMailer::Base
     DEFAULT_HEADERS = {
-      to: 'mikel@test.lindsaar.net',
-      from: 'jose@test.plataformatec.com'
+      to: "mikel@test.lindsaar.net",
+      from: "jose@test.plataformatec.com"
     }
 
-    def welcome(hash={})
+    def welcome(hash = {})
       mail(DEFAULT_HEADERS.merge(hash))
     end
   end
@@ -127,16 +129,16 @@ class MailDeliveryTest < ActiveSupport::TestCase
   end
 
   test "delivery method options default to class level options" do
-    default_options = {a: "b"}
+    default_options = { a: "b" }
     ActionMailer::Base.add_delivery_method :optioned, MyOptionedDelivery, default_options
     mail_instance = DeliveryMailer.welcome(delivery_method: :optioned)
     assert_equal default_options, mail_instance.delivery_method.options
   end
 
   test "delivery method options can be overridden per mail instance" do
-    default_options = {a: "b"}
+    default_options = { a: "b" }
     ActionMailer::Base.add_delivery_method :optioned, MyOptionedDelivery, default_options
-    overridden_options = {a: "a"}
+    overridden_options = { a: "a" }
     mail_instance = DeliveryMailer.welcome(delivery_method: :optioned, delivery_method_options: overridden_options)
     assert_equal overridden_options, mail_instance.delivery_method.options
   end
@@ -145,14 +147,14 @@ class MailDeliveryTest < ActiveSupport::TestCase
     settings = {
       address: "localhost",
       port: 25,
-      domain: 'localhost.localdomain',
+      domain: "localhost.localdomain",
       user_name: nil,
       password: nil,
       authentication: nil,
       enable_starttls_auto: true
     }
     assert_equal settings, ActionMailer::Base.smtp_settings
-    overridden_options = {user_name: "overridden", password: "somethingobtuse"}
+    overridden_options = { user_name: "overridden", password: "somethingobtuse" }
     mail_instance = DeliveryMailer.welcome(delivery_method_options: overridden_options)
     delivery_method_instance = mail_instance.delivery_method
     assert_equal "overridden", delivery_method_instance.settings[:user_name]
diff --git a/actionmailer/test/i18n_with_controller_test.rb b/actionmailer/test/i18n_with_controller_test.rb
index 50c4b74eb8..6e75cff347 100644
--- a/actionmailer/test/i18n_with_controller_test.rb
+++ b/actionmailer/test/i18n_with_controller_test.rb
@@ -1,10 +1,12 @@
-require 'abstract_unit'
-require 'action_view'
-require 'action_controller'
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "action_view"
+require "action_controller"
 
 class I18nTestMailer < ActionMailer::Base
   configure do |c|
-    c.assets_dir = ''
+    c.assets_dir = ""
   end
 
   def mail_with_i18n_subject(recipient)
@@ -18,7 +20,7 @@ end
 class TestController < ActionController::Base
   def send_mail
     email = I18nTestMailer.mail_with_i18n_subject("test@localhost").deliver_now
-    render text: "Mail sent - Subject: #{email.subject}"
+    render plain: "Mail sent - Subject: #{email.subject}"
   end
 end
 
@@ -26,7 +28,7 @@ class ActionMailerI18nWithControllerTest < ActionDispatch::IntegrationTest
   Routes = ActionDispatch::Routing::RouteSet.new
   Routes.draw do
     ActiveSupport::Deprecation.silence do
-      get ':controller(/:action(/:id))'
+      get ":controller(/:action(/:id))"
     end
   end
 
@@ -56,22 +58,20 @@ class ActionMailerI18nWithControllerTest < ActionDispatch::IntegrationTest
   def test_send_mail
     stub_any_instance(Mail::SMTP, instance: Mail::SMTP.new({})) do |instance|
       assert_called(instance, :deliver!) do
-        with_translation 'de', email_subject: '[Anmeldung] Willkommen' do
-          ActiveSupport::Deprecation.silence do
-            get '/test/send_mail'
-          end
+        with_translation "de", email_subject: "[Anmeldung] Willkommen" do
+          get "/test/send_mail"
           assert_equal "Mail sent - Subject: [Anmeldung] Willkommen", @response.body
         end
       end
     end
   end
 
-  protected
+  private
 
-  def with_translation(locale, data)
-    I18n.backend.store_translations(locale, data)
-    yield
-  ensure
-    I18n.backend.reload!
-  end
+    def with_translation(locale, data)
+      I18n.backend.store_translations(locale, data)
+      yield
+    ensure
+      I18n.backend.reload!
+    end
 end
diff --git a/actionmailer/test/log_subscriber_test.rb b/actionmailer/test/log_subscriber_test.rb
index 3871b16840..2e89758dfb 100644
--- a/actionmailer/test/log_subscriber_test.rb
+++ b/actionmailer/test/log_subscriber_test.rb
@@ -1,7 +1,9 @@
-require 'abstract_unit'
-require 'mailers/base_mailer'
-require 'active_support/log_subscriber/test_helper'
-require 'action_mailer/log_subscriber'
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "mailers/base_mailer"
+require "active_support/log_subscriber/test_helper"
+require "action_mailer/log_subscriber"
 
 class AMLogSubscriberTest < ActionMailer::TestCase
   include ActiveSupport::LogSubscriber::TestHelper
@@ -26,7 +28,7 @@ class AMLogSubscriberTest < ActionMailer::TestCase
     wait
 
     assert_equal(1, @logger.logged(:info).size)
-    assert_match(/Sent mail to system@test.lindsaar.net/, @logger.logged(:info).first)
+    assert_match(/Sent mail to system@test\.lindsaar\.net/, @logger.logged(:info).first)
 
     assert_equal(2, @logger.logged(:debug).size)
     assert_match(/BaseMailer#welcome: processed outbound mail in [\d.]+ms/, @logger.logged(:debug).first)
@@ -36,7 +38,7 @@ class AMLogSubscriberTest < ActionMailer::TestCase
   end
 
   def test_receive_is_notified
-    fixture = File.read(File.dirname(__FILE__) + "/fixtures/raw_email")
+    fixture = File.read(File.expand_path("fixtures/raw_email", __dir__))
     TestMailer.receive(fixture)
     wait
     assert_equal(1, @logger.logged(:info).size)
diff --git a/actionmailer/test/mail_helper_test.rb b/actionmailer/test/mail_helper_test.rb
index ff6b25b0c7..51d6ccb10f 100644
--- a/actionmailer/test/mail_helper_test.rb
+++ b/actionmailer/test/mail_helper_test.rb
@@ -1,12 +1,14 @@
-require 'abstract_unit'
+# frozen_string_literal: true
+
+require "abstract_unit"
 
 class HelperMailer < ActionMailer::Base
   def use_mail_helper
-    @text = "But soft! What light through yonder window breaks? It is the east, " +
-            "and Juliet is the sun. Arise, fair sun, and kill the envious moon, " +
-            "which is sick and pale with grief that thou, her maid, art far more " +
-            "fair than she. Be not her maid, for she is envious! Her vestal " +
-            "livery is but sick and green, and none but fools do wear it. Cast " +
+    @text = "But soft! What light through yonder window breaks? It is the east, " \
+            "and Juliet is the sun. Arise, fair sun, and kill the envious moon, " \
+            "which is sick and pale with grief that thou, her maid, art far more " \
+            "fair than she. Be not her maid, for she is envious! Her vestal " \
+            "livery is but sick and green, and none but fools do wear it. Cast " \
             "it off!"
 
     mail_with_defaults do |format|
@@ -65,12 +67,12 @@ The second
     end
   end
 
-  protected
+  private
 
-  def mail_with_defaults(&block)
-    mail(to: "test@localhost", from: "tester@example.com",
-          subject: "using helpers", &block)
-  end
+    def mail_with_defaults(&block)
+      mail(to: "test@localhost", from: "tester@example.com",
+            subject: "using helpers", &block)
+    end
 end
 
 class MailerHelperTest < ActionMailer::TestCase
diff --git a/actionmailer/test/mail_layout_test.rb b/actionmailer/test/mail_layout_test.rb
index 166dd096d4..16d77ed61d 100644
--- a/actionmailer/test/mail_layout_test.rb
+++ b/actionmailer/test/mail_layout_test.rb
@@ -1,7 +1,9 @@
-require 'abstract_unit'
+# frozen_string_literal: true
+
+require "abstract_unit"
 
 class AutoLayoutMailer < ActionMailer::Base
-  default to: 'test@localhost',
+  default to: "test@localhost",
     subject: "You have a mail",
     from: "tester@example.com"
 
@@ -11,7 +13,7 @@ class AutoLayoutMailer < ActionMailer::Base
 
   def spam
     @world = "Earth"
-    mail(body: render(inline: "Hello, <%= @world %>", layout: 'spam'))
+    mail(body: render(inline: "Hello, <%= @world %>", layout: "spam"))
   end
 
   def nolayout
@@ -28,9 +30,9 @@ class AutoLayoutMailer < ActionMailer::Base
 end
 
 class ExplicitLayoutMailer < ActionMailer::Base
-  layout 'spam', except: [:logout]
+  layout "spam", except: [:logout]
 
-  default to: 'test@localhost',
+  default to: "test@localhost",
     subject: "You have a mail",
     from: "tester@example.com"
 
@@ -54,10 +56,10 @@ class LayoutMailerTest < ActiveSupport::TestCase
     assert_equal "multipart/alternative", mail.mime_type
     assert_equal 2, mail.parts.size
 
-    assert_equal 'text/plain', mail.parts.first.mime_type
+    assert_equal "text/plain", mail.parts.first.mime_type
     assert_equal "text/plain layout - text/plain multipart", mail.parts.first.body.to_s
 
-    assert_equal 'text/html', mail.parts.last.mime_type
+    assert_equal "text/html", mail.parts.last.mime_type
     assert_equal "Hello from layout text/html multipart", mail.parts.last.body.to_s
   end
 
@@ -66,10 +68,10 @@ class LayoutMailerTest < ActiveSupport::TestCase
     assert_equal "multipart/mixed", mail.mime_type
     assert_equal 2, mail.parts.size
 
-    assert_equal 'text/plain', mail.parts.first.mime_type
+    assert_equal "text/plain", mail.parts.first.mime_type
     assert_equal "text/plain layout - text/plain multipart", mail.parts.first.body.to_s
 
-    assert_equal 'text/html', mail.parts.last.mime_type
+    assert_equal "text/html", mail.parts.last.mime_type
     assert_equal "Hello from layout text/html multipart", mail.parts.last.body.to_s
   end
 
diff --git a/actionmailer/test/mailers/asset_mailer.rb b/actionmailer/test/mailers/asset_mailer.rb
index f54a50d00d..7a9aba2629 100644
--- a/actionmailer/test/mailers/asset_mailer.rb
+++ b/actionmailer/test/mailers/asset_mailer.rb
@@ -1,7 +1,9 @@
+# frozen_string_literal: true
+
 class AssetMailer < ActionMailer::Base
   self.mailer_name = "asset_mailer"
 
   def welcome
-   mail
+    mail
   end
 end
diff --git a/actionmailer/test/mailers/base_mailer.rb b/actionmailer/test/mailers/base_mailer.rb
index 8c2225ce60..bfaecdb658 100644
--- a/actionmailer/test/mailers/base_mailer.rb
+++ b/actionmailer/test/mailers/base_mailer.rb
@@ -1,13 +1,15 @@
+# frozen_string_literal: true
+
 class BaseMailer < ActionMailer::Base
   self.mailer_name = "base_mailer"
 
-  default to: 'system@test.lindsaar.net',
-          from: 'jose@test.plataformatec.com',
-          reply_to: 'mikel@test.lindsaar.net'
+  default to: "system@test.lindsaar.net",
+          from: "jose@test.plataformatec.com",
+          reply_to: "mikel@test.lindsaar.net"
 
   def welcome(hash = {})
-    headers['X-SPAM'] = "Not SPAM"
-    mail({subject: "The first email on new API!"}.merge!(hash))
+    headers["X-SPAM"] = "Not SPAM"
+    mail({ subject: "The first email on new API!" }.merge!(hash))
   end
 
   def welcome_with_headers(hash = {})
@@ -28,30 +30,30 @@ class BaseMailer < ActionMailer::Base
   end
 
   def inline_attachment
-    attachments.inline['logo.png'] = "\312\213\254\232"
+    attachments.inline["logo.png"] = "\312\213\254\232"
     mail
   end
 
   def attachment_with_content(hash = {})
-    attachments['invoice.pdf'] = 'This is test File content'
+    attachments["invoice.pdf"] = "This is test File content"
     mail(hash)
   end
 
   def attachment_with_hash
-    attachments['invoice.jpg'] = { data: ::Base64.encode64("\312\213\254\232)b"),
+    attachments["invoice.jpg"] = { data: ::Base64.encode64("\312\213\254\232)b"),
                                    mime_type: "image/x-jpg",
                                    transfer_encoding: "base64" }
     mail
   end
 
   def attachment_with_hash_default_encoding
-    attachments['invoice.jpg'] = { data: "\312\213\254\232)b",
+    attachments["invoice.jpg"] = { data: "\312\213\254\232)b",
                                    mime_type: "image/x-jpg" }
     mail
   end
 
   def implicit_multipart(hash = {})
-    attachments['invoice.pdf'] = 'This is test File content' if hash.delete(:attachments)
+    attachments["invoice.pdf"] = "This is test File content" if hash.delete(:attachments)
     mail(hash)
   end
 
@@ -60,10 +62,10 @@ class BaseMailer < ActionMailer::Base
   end
 
   def explicit_multipart(hash = {})
-    attachments['invoice.pdf'] = 'This is test File content' if hash.delete(:attachments)
+    attachments["invoice.pdf"] = "This is test File content" if hash.delete(:attachments)
     mail(hash) do |format|
-      format.text { render text: "TEXT Explicit Multipart" }
-      format.html { render text: "HTML Explicit Multipart" }
+      format.text { render plain: "TEXT Explicit Multipart" }
+      format.html { render plain: "HTML Explicit Multipart" }
     end
   end
 
@@ -76,7 +78,7 @@ class BaseMailer < ActionMailer::Base
 
   def explicit_multipart_with_any(hash = {})
     mail(hash) do |format|
-      format.any(:text, :html){ render text: "Format with any!" }
+      format.any(:text, :html) { render plain: "Format with any!" }
     end
   end
 
@@ -88,8 +90,8 @@ class BaseMailer < ActionMailer::Base
 
   def explicit_multipart_with_options(include_html = false)
     mail do |format|
-      format.text(content_transfer_encoding: "base64"){ render "welcome" }
-      format.html{ render "welcome" } if include_html
+      format.text(content_transfer_encoding: "base64") { render "welcome" }
+      format.html { render "welcome" } if include_html
     end
   end
 
@@ -100,18 +102,18 @@ class BaseMailer < ActionMailer::Base
     end
   end
 
-  def implicit_different_template(template_name='')
+  def implicit_different_template(template_name = "")
     mail(template_name: template_name)
   end
 
-  def explicit_different_template(template_name='')
+  def explicit_different_template(template_name = "")
     mail do |format|
       format.text { render template: "#{mailer_name}/#{template_name}" }
       format.html { render template: "#{mailer_name}/#{template_name}" }
     end
   end
 
-  def different_layout(layout_name='')
+  def different_layout(layout_name = "")
     mail do |format|
       format.text { render layout: layout_name }
       format.html { render layout: layout_name }
@@ -131,6 +133,6 @@ class BaseMailer < ActionMailer::Base
   end
 
   def with_subject_interpolations
-    mail(subject: default_i18n_subject(rapper_or_impersonator: 'Slim Shady'), body: '')
+    mail(subject: default_i18n_subject(rapper_or_impersonator: "Slim Shady"), body: "")
   end
 end
diff --git a/actionmailer/test/mailers/caching_mailer.rb b/actionmailer/test/mailers/caching_mailer.rb
index 92d3cff7c9..02f0c6c103 100644
--- a/actionmailer/test/mailers/caching_mailer.rb
+++ b/actionmailer/test/mailers/caching_mailer.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class CachingMailer < ActionMailer::Base
   self.mailer_name = "caching_mailer"
 
diff --git a/actionmailer/test/mailers/delayed_mailer.rb b/actionmailer/test/mailers/delayed_mailer.rb
index e6211ef028..b0f5ecc2fb 100644
--- a/actionmailer/test/mailers/delayed_mailer.rb
+++ b/actionmailer/test/mailers/delayed_mailer.rb
@@ -1,4 +1,6 @@
-require 'active_job/arguments'
+# frozen_string_literal: true
+
+require "active_job/arguments"
 
 class DelayedMailerError < StandardError; end
 
@@ -17,10 +19,10 @@ class DelayedMailer < ActionMailer::Base
   end
 
   def test_message(*)
-    mail(from: 'test-sender@test.com', to: 'test-receiver@test.com', subject: 'Test Subject', body: 'Test Body')
+    mail(from: "test-sender@test.com", to: "test-receiver@test.com", subject: "Test Subject", body: "Test Body")
   end
 
   def test_raise(klass_name)
-    raise klass_name.constantize, 'boom'
+    raise klass_name.constantize, "boom"
   end
 end
diff --git a/actionmailer/test/mailers/params_mailer.rb b/actionmailer/test/mailers/params_mailer.rb
new file mode 100644
index 0000000000..84aa336311
--- /dev/null
+++ b/actionmailer/test/mailers/params_mailer.rb
@@ -0,0 +1,13 @@
+# frozen_string_literal: true
+
+class ParamsMailer < ActionMailer::Base
+  before_action { @inviter, @invitee = params[:inviter], params[:invitee] }
+
+  default to: Proc.new { @invitee }, from: -> { @inviter }
+
+  def invitation
+    mail(subject: "Welcome to the project!") do |format|
+      format.text { render plain: "So says #{@inviter}" }
+    end
+  end
+end
diff --git a/actionmailer/test/mailers/proc_mailer.rb b/actionmailer/test/mailers/proc_mailer.rb
index 7e189d861f..b7cf53eb4a 100644
--- a/actionmailer/test/mailers/proc_mailer.rb
+++ b/actionmailer/test/mailers/proc_mailer.rb
@@ -1,8 +1,10 @@
+# frozen_string_literal: true
+
 class ProcMailer < ActionMailer::Base
-  default to: 'system@test.lindsaar.net',
-          'X-Proc-Method' => Proc.new { Time.now.to_i.to_s },
+  default to: "system@test.lindsaar.net",
+          "X-Proc-Method" => Proc.new { Time.now.to_i.to_s },
           subject: Proc.new { give_a_greeting },
-          'x-has-to-proc' => :symbol
+          "x-has-to-proc" => :symbol
 
   def welcome
     mail
@@ -10,8 +12,7 @@ class ProcMailer < ActionMailer::Base
 
   private
 
-  def give_a_greeting
-    "Thanks for signing up this afternoon"
-  end
-
+    def give_a_greeting
+      "Thanks for signing up this afternoon"
+    end
 end
diff --git a/actionmailer/test/message_delivery_test.rb b/actionmailer/test/message_delivery_test.rb
index aaed94d519..f8dcb3f4ba 100644
--- a/actionmailer/test/message_delivery_test.rb
+++ b/actionmailer/test/message_delivery_test.rb
@@ -1,6 +1,8 @@
-require 'abstract_unit'
-require 'active_job'
-require 'mailers/delayed_mailer'
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "active_job"
+require "mailers/delayed_mailer"
 
 class MessageDeliveryTest < ActiveSupport::TestCase
   include ActiveJob::TestHelper
@@ -12,7 +14,6 @@ class MessageDeliveryTest < ActiveSupport::TestCase
     ActionMailer::Base.deliver_later_queue_name = :test_queue
     ActionMailer::Base.delivery_method = :test
     ActiveJob::Base.logger = Logger.new(nil)
-    ActionMailer::Base.deliveries.clear
     ActiveJob::Base.queue_adapter.perform_enqueued_at_jobs = true
     ActiveJob::Base.queue_adapter.perform_enqueued_jobs = true
 
@@ -23,6 +24,8 @@ class MessageDeliveryTest < ActiveSupport::TestCase
   end
 
   teardown do
+    ActionMailer::Base.deliveries.clear
+
     ActiveJob::Base.logger = @previous_logger
     ActionMailer::Base.delivery_method = @previous_delivery_method
     ActionMailer::Base.deliver_later_queue_name = @previous_deliver_later_queue_name
@@ -31,77 +34,88 @@ class MessageDeliveryTest < ActiveSupport::TestCase
     DelayedMailer.last_rescue_from_instance = nil
   end
 
-  test 'should have a message' do
+  test "should have a message" do
     assert @mail.message
   end
 
-  test 'its message should be a Mail::Message' do
-    assert_equal Mail::Message , @mail.message.class
+  test "its message should be a Mail::Message" do
+    assert_equal Mail::Message, @mail.message.class
   end
 
-  test 'should respond to .deliver_later' do
+  test "should respond to .deliver_later" do
     assert_respond_to @mail, :deliver_later
   end
 
-  test 'should respond to .deliver_later!' do
+  test "should respond to .deliver_later!" do
     assert_respond_to @mail, :deliver_later!
   end
 
-  test 'should respond to .deliver_now' do
+  test "should respond to .deliver_now" do
     assert_respond_to @mail, :deliver_now
   end
 
-  test 'should respond to .deliver_now!' do
+  test "should respond to .deliver_now!" do
     assert_respond_to @mail, :deliver_now!
   end
 
   def test_should_enqueue_and_run_correctly_in_activejob
     @mail.deliver_later!
     assert_equal 1, ActionMailer::Base.deliveries.size
-  ensure
-    ActionMailer::Base.deliveries.clear
   end
 
-  test 'should enqueue the email with :deliver_now delivery method' do
-    assert_performed_with(job: ActionMailer::DeliveryJob, args: ['DelayedMailer', 'test_message', 'deliver_now', 1, 2, 3]) do
+  test "should enqueue the email with :deliver_now delivery method" do
+    assert_performed_with(job: ActionMailer::DeliveryJob, args: ["DelayedMailer", "test_message", "deliver_now", 1, 2, 3]) do
       @mail.deliver_later
     end
   end
 
-  test 'should enqueue the email with :deliver_now! delivery method' do
-    assert_performed_with(job: ActionMailer::DeliveryJob, args: ['DelayedMailer', 'test_message', 'deliver_now!', 1, 2, 3]) do
+  test "should enqueue the email with :deliver_now! delivery method" do
+    assert_performed_with(job: ActionMailer::DeliveryJob, args: ["DelayedMailer", "test_message", "deliver_now!", 1, 2, 3]) do
       @mail.deliver_later!
     end
   end
 
-  test 'should enqueue a delivery with a delay' do
+  test "should enqueue a delivery with a delay" do
     travel_to Time.new(2004, 11, 24, 01, 04, 44) do
-      assert_performed_with(job: ActionMailer::DeliveryJob, at: Time.current.to_f+600.seconds, args: ['DelayedMailer', 'test_message', 'deliver_now', 1, 2, 3]) do
-        @mail.deliver_later wait: 600.seconds
+      assert_performed_with(job: ActionMailer::DeliveryJob, at: Time.current + 10.minutes, args: ["DelayedMailer", "test_message", "deliver_now", 1, 2, 3]) do
+        @mail.deliver_later wait: 10.minutes
       end
     end
   end
 
-  test 'should enqueue a delivery at a specific time' do
-    later_time = Time.now.to_f + 3600
-    assert_performed_with(job: ActionMailer::DeliveryJob, at: later_time, args: ['DelayedMailer', 'test_message', 'deliver_now', 1, 2, 3]) do
+  test "should enqueue a delivery at a specific time" do
+    later_time = Time.current + 1.hour
+    assert_performed_with(job: ActionMailer::DeliveryJob, at: later_time, args: ["DelayedMailer", "test_message", "deliver_now", 1, 2, 3]) do
       @mail.deliver_later wait_until: later_time
     end
   end
 
-  test 'should enqueue the job on the correct queue' do
-    assert_performed_with(job: ActionMailer::DeliveryJob, args: ['DelayedMailer', 'test_message', 'deliver_now', 1, 2, 3], queue: "test_queue") do
+  test "should enqueue the job on the correct queue" do
+    assert_performed_with(job: ActionMailer::DeliveryJob, args: ["DelayedMailer", "test_message", "deliver_now", 1, 2, 3], queue: "test_queue") do
+      @mail.deliver_later
+    end
+  end
+
+  test "should enqueue the job with the correct delivery job" do
+    old_delivery_job = DelayedMailer.delivery_job
+    DelayedMailer.delivery_job = DummyJob
+
+    assert_performed_with(job: DummyJob, args: ["DelayedMailer", "test_message", "deliver_now", 1, 2, 3]) do
       @mail.deliver_later
     end
+
+    DelayedMailer.delivery_job = old_delivery_job
   end
 
-  test 'can override the queue when enqueuing mail' do
-    assert_performed_with(job: ActionMailer::DeliveryJob, args: ['DelayedMailer', 'test_message', 'deliver_now', 1, 2, 3], queue: "another_queue") do
+  class DummyJob < ActionMailer::DeliveryJob; end
+
+  test "can override the queue when enqueuing mail" do
+    assert_performed_with(job: ActionMailer::DeliveryJob, args: ["DelayedMailer", "test_message", "deliver_now", 1, 2, 3], queue: "another_queue") do
       @mail.deliver_later(queue: :another_queue)
     end
   end
 
-  test 'deliver_later after accessing the message is disallowed' do
+  test "deliver_later after accessing the message is disallowed" do
     @mail.message # Load the message, which calls the mailer method.
 
     assert_raise RuntimeError do
@@ -109,17 +123,17 @@ class MessageDeliveryTest < ActiveSupport::TestCase
     end
   end
 
-  test 'job delegates error handling to mailer' do
+  test "job delegates error handling to mailer" do
     # Superclass not rescued by mailer's rescue_from RuntimeError
-    message = DelayedMailer.test_raise('StandardError')
+    message = DelayedMailer.test_raise("StandardError")
     assert_raise(StandardError) { message.deliver_later }
     assert_nil DelayedMailer.last_error
     assert_nil DelayedMailer.last_rescue_from_instance
 
     # Rescued by mailer's rescue_from RuntimeError
-    message = DelayedMailer.test_raise('DelayedMailerError')
+    message = DelayedMailer.test_raise("DelayedMailerError")
     assert_nothing_raised { message.deliver_later }
-    assert_equal 'boom', DelayedMailer.last_error.message
+    assert_equal "boom", DelayedMailer.last_error.message
     assert_kind_of DelayedMailer, DelayedMailer.last_rescue_from_instance
   end
 
@@ -127,7 +141,7 @@ class MessageDeliveryTest < ActiveSupport::TestCase
     include GlobalID::Identification
 
     def self.find(id)
-      raise 'boom, missing find'
+      raise "boom, missing find"
     end
 
     attr_reader :id
@@ -136,11 +150,11 @@ class MessageDeliveryTest < ActiveSupport::TestCase
     end
 
     def to_global_id(options = {})
-      super app: 'foo'
+      super app: "foo"
     end
   end
 
-  test 'job delegates deserialization errors to mailer class' do
+  test "job delegates deserialization errors to mailer class" do
     # Inject an argument that can't be deserialized.
     message = DelayedMailer.test_message(DeserializationErrorFixture.new)
 
@@ -148,6 +162,6 @@ class MessageDeliveryTest < ActiveSupport::TestCase
     # on the mailer class.
     assert_nothing_raised { message.deliver_later }
     assert_equal DelayedMailer, DelayedMailer.last_rescue_from_instance
-    assert_equal 'Error while trying to deserialize arguments: boom, missing find', DelayedMailer.last_error.message
+    assert_equal "Error while trying to deserialize arguments: boom, missing find", DelayedMailer.last_error.message
   end
 end
diff --git a/actionmailer/test/parameterized_test.rb b/actionmailer/test/parameterized_test.rb
new file mode 100644
index 0000000000..ec6c5e9e67
--- /dev/null
+++ b/actionmailer/test/parameterized_test.rb
@@ -0,0 +1,56 @@
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "active_job"
+require "mailers/params_mailer"
+
+class ParameterizedTest < ActiveSupport::TestCase
+  include ActiveJob::TestHelper
+
+  setup do
+    @previous_logger = ActiveJob::Base.logger
+    ActiveJob::Base.logger = Logger.new(nil)
+
+    @previous_delivery_method = ActionMailer::Base.delivery_method
+    ActionMailer::Base.delivery_method = :test
+
+    @previous_deliver_later_queue_name = ActionMailer::Base.deliver_later_queue_name
+    ActionMailer::Base.deliver_later_queue_name = :test_queue
+
+    @mail = ParamsMailer.with(inviter: "david@basecamp.com", invitee: "jason@basecamp.com").invitation
+  end
+
+  teardown do
+    ActiveJob::Base.logger = @previous_logger
+    ParamsMailer.deliveries.clear
+
+    ActionMailer::Base.delivery_method = @previous_delivery_method
+    ActionMailer::Base.deliver_later_queue_name = @previous_deliver_later_queue_name
+  end
+
+  test "parameterized headers" do
+    assert_equal(["jason@basecamp.com"], @mail.to)
+    assert_equal(["david@basecamp.com"], @mail.from)
+    assert_equal("So says david@basecamp.com", @mail.body.encoded)
+  end
+
+  test "enqueue the email with params" do
+    assert_performed_with(job: ActionMailer::Parameterized::DeliveryJob, args: ["ParamsMailer", "invitation", "deliver_now", { inviter: "david@basecamp.com", invitee: "jason@basecamp.com" } ]) do
+      @mail.deliver_later
+    end
+  end
+
+  test "respond_to?" do
+    mailer = ParamsMailer.with(inviter: "david@basecamp.com", invitee: "jason@basecamp.com")
+
+    assert_respond_to mailer, :invitation
+    assert_not_respond_to mailer, :anything
+
+    invitation = mailer.method(:invitation)
+    assert_equal Method, invitation.class
+
+    assert_raises(NameError) do
+      invitation = mailer.method(:anything)
+    end
+  end
+end
diff --git a/actionmailer/test/test_case_test.rb b/actionmailer/test/test_case_test.rb
index 5d8d3c3b36..7b9647d295 100644
--- a/actionmailer/test/test_case_test.rb
+++ b/actionmailer/test/test_case_test.rb
@@ -1,4 +1,6 @@
-require 'abstract_unit'
+# frozen_string_literal: true
+
+require "abstract_unit"
 
 class TestTestMailer < ActionMailer::Base
 end
@@ -8,7 +10,7 @@ class ClearTestDeliveriesMixinTest < ActiveSupport::TestCase
 
   def before_setup
     ActionMailer::Base.delivery_method, @original_delivery_method = :test, ActionMailer::Base.delivery_method
-    ActionMailer::Base.deliveries << 'better clear me, setup'
+    ActionMailer::Base.deliveries << "better clear me, setup"
     super
   end
 
@@ -20,13 +22,13 @@ class ClearTestDeliveriesMixinTest < ActiveSupport::TestCase
 
   def test_deliveries_are_cleared_on_setup_and_teardown
     assert_equal [], ActionMailer::Base.deliveries
-    ActionMailer::Base.deliveries << 'better clear me, teardown'
+    ActionMailer::Base.deliveries << "better clear me, teardown"
   end
 end
 
 class MailerDeliveriesClearingTest < ActionMailer::TestCase
   def before_setup
-    ActionMailer::Base.deliveries << 'better clear me, setup'
+    ActionMailer::Base.deliveries << "better clear me, setup"
     super
   end
 
@@ -37,7 +39,7 @@ class MailerDeliveriesClearingTest < ActionMailer::TestCase
 
   def test_deliveries_are_cleared_on_setup_and_teardown
     assert_equal [], ActionMailer::Base.deliveries
-    ActionMailer::Base.deliveries << 'better clear me, teardown'
+    ActionMailer::Base.deliveries << "better clear me, teardown"
   end
 end
 
@@ -58,7 +60,7 @@ class CrazySymbolNameMailerTest < ActionMailer::TestCase
 end
 
 class CrazyStringNameMailerTest < ActionMailer::TestCase
-  tests 'test_test_mailer'
+  tests "test_test_mailer"
 
   def test_set_mailer_class_manual_using_string
     assert_equal TestTestMailer, self.class.mailer_class
diff --git a/actionmailer/test/test_helper_test.rb b/actionmailer/test/test_helper_test.rb
index 0a4bc75d3e..3866097389 100644
--- a/actionmailer/test/test_helper_test.rb
+++ b/actionmailer/test/test_helper_test.rb
@@ -1,5 +1,7 @@
-require 'abstract_unit'
-require 'active_support/testing/stream'
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "active_support/testing/stream"
 
 class TestHelperMailer < ActionMailer::Base
   def test
@@ -8,6 +10,18 @@ class TestHelperMailer < ActionMailer::Base
       to: "test@example.com",
       from: "tester@example.com"
   end
+
+  def test_args(recipient, name)
+    mail body: render(inline: "Hello, #{name}"),
+      to: recipient,
+      from: "tester@example.com"
+  end
+
+  def test_parameter_args
+    mail body: render(inline: "All is #{params[:all]}"),
+      to: "test@example.com",
+      from: "tester@example.com"
+  end
 end
 
 class TestHelperMailerTest < ActionMailer::TestCase
@@ -40,11 +54,11 @@ class TestHelperMailerTest < ActionMailer::TestCase
   end
 
   def test_encode
-    assert_equal '=?UTF-8?Q?This_is_=E3=81=82_string?=', encode('This is あ string')
+    assert_equal "This is あ string", Mail::Encodings.q_value_decode(encode("This is あ string"))
   end
 
   def test_read_fixture
-    assert_equal ['Welcome!'], read_fixture('welcome')
+    assert_equal ["Welcome!"], read_fixture("welcome")
   end
 
   def test_assert_emails
@@ -143,6 +157,16 @@ class TestHelperMailerTest < ActionMailer::TestCase
     end
   end
 
+  def test_assert_enqueued_parameterized_emails
+    assert_nothing_raised do
+      assert_enqueued_emails 1 do
+        silence_stream($stdout) do
+          TestHelperMailer.with(a: 1).test.deliver_later
+        end
+      end
+    end
+  end
+
   def test_assert_enqueued_emails_too_few_sent
     error = assert_raise ActiveSupport::TestCase::Assertion do
       assert_enqueued_emails 2 do
@@ -176,6 +200,14 @@ class TestHelperMailerTest < ActionMailer::TestCase
     end
   end
 
+  def test_assert_no_enqueued_parameterized_emails
+    assert_nothing_raised do
+      assert_no_enqueued_emails do
+        TestHelperMailer.with(a: 1).test.deliver_now
+      end
+    end
+  end
+
   def test_assert_no_enqueued_emails_failure
     error = assert_raise ActiveSupport::TestCase::Assertion do
       assert_no_enqueued_emails do
@@ -187,6 +219,36 @@ class TestHelperMailerTest < ActionMailer::TestCase
 
     assert_match(/0 .* but 1/, error.message)
   end
+
+  def test_assert_enqueued_email_with
+    assert_nothing_raised do
+      assert_enqueued_email_with TestHelperMailer, :test do
+        silence_stream($stdout) do
+          TestHelperMailer.test.deliver_later
+        end
+      end
+    end
+  end
+
+  def test_assert_enqueued_email_with_args
+    assert_nothing_raised do
+      assert_enqueued_email_with TestHelperMailer, :test_args, args: ["some_email", "some_name"] do
+        silence_stream($stdout) do
+          TestHelperMailer.test_args("some_email", "some_name").deliver_later
+        end
+      end
+    end
+  end
+
+  def test_assert_enqueued_email_with_parameterized_args
+    assert_nothing_raised do
+      assert_enqueued_email_with TestHelperMailer, :test_parameter_args, args: { all: "good" } do
+        silence_stream($stdout) do
+          TestHelperMailer.with(all: "good").test_parameter_args.deliver_later
+        end
+      end
+    end
+  end
 end
 
 class AnotherTestHelperMailerTest < ActionMailer::TestCase
@@ -198,6 +260,6 @@ class AnotherTestHelperMailerTest < ActionMailer::TestCase
 
   def test_setup_shouldnt_conflict_with_mailer_setup
     assert_kind_of Mail::Message, @expected
-    assert_equal 'a value', @test_var
+    assert_equal "a value", @test_var
   end
 end
diff --git a/actionmailer/test/url_test.rb b/actionmailer/test/url_test.rb
index 70bd05055f..3c940bc969 100644
--- a/actionmailer/test/url_test.rb
+++ b/actionmailer/test/url_test.rb
@@ -1,5 +1,7 @@
-require 'abstract_unit'
-require 'action_controller'
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "action_controller"
 
 class WelcomeController < ActionController::Base
 end
@@ -11,10 +13,10 @@ class ActionMailer::Base
 end
 
 class UrlTestMailer < ActionMailer::Base
-  default_url_options[:host] = 'www.basecamphq.com'
+  default_url_options[:host] = "www.basecamphq.com"
 
   configure do |c|
-    c.assets_dir = '' # To get the tests to pass
+    c.assets_dir = "" # To get the tests to pass
   end
 
   def signed_up_with_url(recipient)
@@ -27,14 +29,14 @@ class UrlTestMailer < ActionMailer::Base
   def exercise_url_for(options)
     @options = options
     @url = url_for(@options)
-    mail(from: 'from@example.com', to: 'to@example.com', subject: 'subject')
+    mail(from: "from@example.com", to: "to@example.com", subject: "subject")
   end
 end
 
 class ActionMailerUrlTest < ActionMailer::TestCase
   class DummyModel
     def self.model_name
-      OpenStruct.new(route_key: 'dummy_model')
+      OpenStruct.new(route_key: "dummy_model")
     end
 
     def persisted?
@@ -50,11 +52,11 @@ class ActionMailerUrlTest < ActionMailer::TestCase
     end
   end
 
-  def encode( text, charset="UTF-8" )
-    quoted_printable( text, charset )
+  def encode(text, charset = "UTF-8")
+    quoted_printable(text, charset)
   end
 
-  def new_mail( charset="UTF-8" )
+  def new_mail(charset = "UTF-8")
     mail = Mail.new
     mail.mime_version = "1.0"
     if charset
@@ -64,7 +66,7 @@ class ActionMailerUrlTest < ActionMailer::TestCase
   end
 
   def assert_url_for(expected, options, relative = false)
-    expected = "http://www.basecamphq.com#{expected}" if expected.start_with?('/') && !relative
+    expected = "http://www.basecamphq.com#{expected}" if expected.start_with?("/") && !relative
     urls = UrlTestMailer.exercise_url_for(options).body.to_s.chomp.split
 
     assert_equal expected, urls.first
@@ -72,7 +74,7 @@ class ActionMailerUrlTest < ActionMailer::TestCase
   end
 
   def setup
-    @recipient = 'test@localhost'
+    @recipient = "test@localhost"
   end
 
   def test_url_for
@@ -80,30 +82,30 @@ class ActionMailerUrlTest < ActionMailer::TestCase
 
     AppRoutes.draw do
       ActiveSupport::Deprecation.silence do
-        get ':controller(/:action(/:id))'
-        get '/welcome'  => 'foo#bar', as: 'welcome'
-        get '/dummy_model' => 'foo#baz', as: 'dummy_model'
+        get ":controller(/:action(/:id))"
+        get "/welcome" => "foo#bar", as: "welcome"
+        get "/dummy_model" => "foo#baz", as: "dummy_model"
       end
     end
 
     # string
-    assert_url_for 'http://foo/', 'http://foo/'
+    assert_url_for "http://foo/", "http://foo/"
 
     # symbol
-    assert_url_for '/welcome', :welcome
+    assert_url_for "/welcome", :welcome
 
     # hash
-    assert_url_for '/a/b/c', controller: 'a', action: 'b', id: 'c'
-    assert_url_for '/a/b/c', {controller: 'a', action: 'b', id: 'c', only_path: true}, true
+    assert_url_for "/a/b/c", controller: "a", action: "b", id: "c"
+    assert_url_for "/a/b/c", { controller: "a", action: "b", id: "c", only_path: true }, true
 
     # model
-    assert_url_for '/dummy_model', DummyModel.new
+    assert_url_for "/dummy_model", DummyModel.new
 
     # class
-    assert_url_for '/dummy_model', DummyModel
+    assert_url_for "/dummy_model", DummyModel
 
     # array
-    assert_url_for '/dummy_model' , [DummyModel]
+    assert_url_for "/dummy_model", [DummyModel]
   end
 
   def test_signed_up_with_url
@@ -111,15 +113,15 @@ class ActionMailerUrlTest < ActionMailer::TestCase
 
     AppRoutes.draw do
       ActiveSupport::Deprecation.silence do
-        get ':controller(/:action(/:id))'
-        get '/welcome' => "foo#bar", as: "welcome"
+        get ":controller(/:action(/:id))"
+        get "/welcome" => "foo#bar", as: "welcome"
       end
     end
 
     expected = new_mail
     expected.to      = @recipient
     expected.subject = "[Signed up] Welcome #{@recipient}"
-    expected.body    = "Hello there,\n\nMr. #{@recipient}. Please see our greeting at http://example.com/welcome/greeting http://www.basecamphq.com/welcome\n\n<img alt=\"Somelogo\" src=\"/images/somelogo.png\" />"
+    expected.body    = "Hello there,\n\nMr. #{@recipient}. Please see our greeting at http://example.com/welcome/greeting http://www.basecamphq.com/welcome\n\n<img src=\"/images/somelogo.png\" />"
     expected.from    = "system@loudthinking.com"
     expected.date    = Time.local(2004, 12, 12)
     expected.content_type = "text/html"
@@ -128,15 +130,15 @@ class ActionMailerUrlTest < ActionMailer::TestCase
     assert_nothing_raised { created = UrlTestMailer.signed_up_with_url(@recipient) }
     assert_not_nil created
 
-    expected.message_id = '<123@456>'
-    created.message_id = '<123@456>'
+    expected.message_id = "<123@456>"
+    created.message_id = "<123@456>"
     assert_dom_equal expected.encoded, created.encoded
 
     assert_nothing_raised { UrlTestMailer.signed_up_with_url(@recipient).deliver_now }
     assert_not_nil ActionMailer::Base.deliveries.first
     delivered = ActionMailer::Base.deliveries.first
 
-    delivered.message_id = '<123@456>'
+    delivered.message_id = "<123@456>"
     assert_dom_equal expected.encoded, delivered.encoded
   end
 end
diff --git a/actionpack/CHANGELOG.md b/actionpack/CHANGELOG.md
index be911b147c..c75f0e83ac 100644
--- a/actionpack/CHANGELOG.md
+++ b/actionpack/CHANGELOG.md
@@ -1,2 +1,243 @@
+*   Changed the system tests to set Puma as default server only when the
+    user haven't specified manually another server.
 
-Please check [5-0-stable](https://github.com/rails/rails/blob/5-0-stable/actionpack/CHANGELOG.md) for previous changes.
+    *Guillermo Iguaran*
+
+*   Add secure `X-Download-Options` and `X-Permitted-Cross-Domain-Policies` to
+    default headers set.
+
+    *Guillermo Iguaran*
+
+*   Add headless firefox support to System Tests.
+
+    *bogdanvlviv*
+
+*   Changed the default system test screenshot output from `inline` to `simple`.
+
+    `inline` works well for iTerm2 but not everyone uses iTerm2. Some terminals like
+    Terminal.app ignore the `inline` and output the path to the file since it can't
+    render the image. Other terminals, like those on Ubuntu, cannot handle the image
+    inline, but also don't handle it gracefully and instead of outputting the file
+    path, it dumps binary into the terminal.
+
+    Commit 9d6e28 fixes this by changing the default for screenshot to be `simple`.
+
+    *Eileen M. Uchitelle*
+
+*   Register most popular audio/video/font mime types supported by modern browsers.
+
+    *Guillermo Iguaran*
+
+*   Fix optimized url helpers when using relative url root
+
+    Fixes #31220.
+
+    *Andrew White*
+
+
+## Rails 5.2.0.beta2 (November 28, 2017) ##
+
+*   No changes.
+
+
+## Rails 5.2.0.beta1 (November 27, 2017) ##
+
+*   Add DSL for configuring Content-Security-Policy header
+
+    The DSL allows you to configure a global Content-Security-Policy
+    header and then override within a controller. For more information
+    about the Content-Security-Policy header see MDN:
+
+    https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Content-Security-Policy
+
+    Example global policy:
+
+        # config/initializers/content_security_policy.rb
+        Rails.application.config.content_security_policy do |p|
+          p.default_src :self, :https
+          p.font_src    :self, :https, :data
+          p.img_src     :self, :https, :data
+          p.object_src  :none
+          p.script_src  :self, :https
+          p.style_src   :self, :https, :unsafe_inline
+        end
+
+    Example controller overrides:
+
+        # Override policy inline
+        class PostsController < ApplicationController
+          content_security_policy do |p|
+            p.upgrade_insecure_requests true
+          end
+        end
+
+        # Using literal values
+        class PostsController < ApplicationController
+          content_security_policy do |p|
+            p.base_uri "https://www.example.com"
+          end
+        end
+
+        # Using mixed static and dynamic values
+        class PostsController < ApplicationController
+          content_security_policy do |p|
+            p.base_uri :self, -> { "https://#{current_user.domain}.example.com" }
+          end
+        end
+
+    Allows you to also only report content violations for migrating
+    legacy content using the `content_security_policy_report_only`
+    configuration attribute, e.g;
+
+        # config/initializers/content_security_policy.rb
+        Rails.application.config.content_security_policy_report_only = true
+
+        # controller override
+        class PostsController < ApplicationController
+          self.content_security_policy_report_only = true
+        end
+
+    Note that this feature does not validate the header for performance
+    reasons since the header is calculated at runtime.
+
+    *Andrew White*
+
+*   Make `assert_recognizes` to traverse mounted engines
+
+    *Yuichiro Kaneko*
+
+*   Remove deprecated `ActionController::ParamsParser::ParseError`.
+
+    *Rafael Mendonça França*
+
+*   Add `:allow_other_host` option to `redirect_back` method.
+
+    When `allow_other_host` is set to `false`, the `redirect_back` will not allow redirecting from a
+    different host. `allow_other_host` is `true` by default.
+
+    *Tim Masliuchenko*
+
+*   Add headless chrome support to System Tests.
+
+    *Yuji Yaginuma*
+
+*   Add ability to enable Early Hints for HTTP/2
+
+    If supported by the server, and enabled in Puma this allows H2 Early Hints to be used.
+
+    The `javascript_include_tag` and the `stylesheet_link_tag` automatically add Early Hints if requested.
+
+    *Eileen M. Uchitelle*, *Aaron Patterson*
+
+*   Simplify cookies middleware with key rotation support
+
+    Use the `rotate` method for both `MessageEncryptor` and
+    `MessageVerifier` to add key rotation support for encrypted and
+    signed cookies. This also helps simplify support for legacy cookie
+    security.
+
+    *Michael J Coyne*
+
+*   Use Capybara registered `:puma` server config.
+
+    The Capybara registered `:puma` server ensures the puma server is run in process so
+    connection sharing and open request detection work correctly by default.
+
+    *Thomas Walpole*
+
+*   Cookies `:expires` option supports `ActiveSupport::Duration` object.
+
+        cookies[:user_name] = { value: "assain", expires: 1.hour }
+        cookies[:key] = { value: "a yummy cookie", expires: 6.months }
+
+    Pull Request: #30121
+
+    *Assain Jaleel*
+
+*   Enforce signed/encrypted cookie expiry server side.
+
+    Rails can thwart attacks by malicious clients that don't honor a cookie's expiry.
+
+    It does so by stashing the expiry within the written cookie and relying on the
+    signing/encrypting to vouch that it hasn't been tampered with. Then on a
+    server-side read, the expiry is verified and any expired cookie is discarded.
+
+    Pull Request: #30121
+
+    *Assain Jaleel*
+
+*   Make `take_failed_screenshot` work within engine.
+
+    Fixes #30405.
+
+    *Yuji Yaginuma*
+
+*   Deprecate `ActionDispatch::TestResponse` response aliases
+
+    `#success?`, `#missing?` & `#error?` are not supported by the actual
+    `ActionDispatch::Response` object and can produce false-positives. Instead,
+    use the response helpers provided by `Rack::Response`.
+
+    *Trevor Wistaff*
+
+*   Protect from forgery by default
+
+    Rather than protecting from forgery in the generated `ApplicationController`,
+    add it to `ActionController::Base` depending on
+    `config.action_controller.default_protect_from_forgery`. This configuration
+    defaults to false to support older versions which have removed it from their
+    `ApplicationController`, but is set to true for Rails 5.2.
+
+    *Lisa Ugray*
+
+*   Fallback `ActionController::Parameters#to_s` to `Hash#to_s`.
+
+    *Kir Shatrov*
+
+*   `driven_by` now registers poltergeist and capybara-webkit.
+
+    If poltergeist or capybara-webkit are set as drivers is set for System Tests,
+    `driven_by` will register the driver and set additional options passed via
+    the `:options` parameter.
+
+    Refer to the respective driver's documentation to see what options can be passed.
+
+    *Mario Chavez*
+
+*   AEAD encrypted cookies and sessions with GCM.
+
+    Encrypted cookies now use AES-GCM which couples authentication and
+    encryption in one faster step and produces shorter ciphertexts. Cookies
+    encrypted using AES in CBC HMAC mode will be seamlessly upgraded when
+    this new mode is enabled via the
+    `action_dispatch.use_authenticated_cookie_encryption` configuration value.
+
+    *Michael J Coyne*
+
+*   Change the cache key format for fragments to make it easier to debug key churn. The new format is:
+
+        views/template/action.html.erb:7a1156131a6928cb0026877f8b749ac9/projects/123
+              ^template path           ^template tree digest            ^class   ^id
+
+    *DHH*
+
+*   Add support for recyclable cache keys with fragment caching. This uses the new versioned entries in the
+    `ActiveSupport::Cache` stores and relies on the fact that Active Record has split `#cache_key` and `#cache_version`
+    to support it.
+
+    *DHH*
+
+*   Add `action_controller_api` and `action_controller_base` load hooks to be called in `ActiveSupport.on_load`
+
+    `ActionController::Base` and `ActionController::API` have differing implementations. This means that
+    the one umbrella hook `action_controller` is not able to address certain situations where a method
+    may not exist in a certain implementation.
+
+    This is fixed by adding two new hooks so you can target `ActionController::Base` vs `ActionController::API`
+
+    Fixes #27013.
+
+    *Julian Nadeau*
+
+
+Please check [5-1-stable](https://github.com/rails/rails/blob/5-1-stable/actionpack/CHANGELOG.md) for previous changes.
diff --git a/actionpack/MIT-LICENSE b/actionpack/MIT-LICENSE
index 8573eb1225..1cb3add0fc 100644
--- a/actionpack/MIT-LICENSE
+++ b/actionpack/MIT-LICENSE
@@ -1,4 +1,4 @@
-Copyright (c) 2004-2016 David Heinemeier Hansson
+Copyright (c) 2004-2018 David Heinemeier Hansson
 
 Permission is hereby granted, free of charge, to any person obtaining
 a copy of this software and associated documentation files (the
diff --git a/actionpack/README.rdoc b/actionpack/README.rdoc
index 0720c66cb9..f56230ffa0 100644
--- a/actionpack/README.rdoc
+++ b/actionpack/README.rdoc
@@ -30,7 +30,7 @@ The latest version of Action Pack can be installed with RubyGems:
 
   $ gem install actionpack
 
-Source code can be downloaded as part of the Rails project on GitHub
+Source code can be downloaded as part of the Rails project on GitHub:
 
 * https://github.com/rails/rails/tree/master/actionpack
 
@@ -39,16 +39,16 @@ Source code can be downloaded as part of the Rails project on GitHub
 
 Action Pack is released under the MIT license:
 
-* http://www.opensource.org/licenses/MIT
+* https://opensource.org/licenses/MIT
 
 
 == Support
 
-API documentation is at
+API documentation is at:
 
 * http://api.rubyonrails.org
 
-Bug reports can be filed for the Ruby on Rails project here:
+Bug reports for the Ruby on Rails project can be filed here:
 
 * https://github.com/rails/rails/issues
 
diff --git a/actionpack/Rakefile b/actionpack/Rakefile
index 4a05c067a9..4dd7c59ce8 100644
--- a/actionpack/Rakefile
+++ b/actionpack/Rakefile
@@ -1,15 +1,17 @@
-require 'rake/testtask'
+# frozen_string_literal: true
 
-test_files = Dir.glob('test/**/*_test.rb')
+require "rake/testtask"
+
+test_files = Dir.glob("test/**/*_test.rb")
 
 desc "Default Task"
-task :default => :test
+task default: :test
 
 task :package
 
 # Run the unit tests
 Rake::TestTask.new do |t|
-  t.libs << 'test'
+  t.libs << "test"
   t.test_files = test_files
 
   t.warning = true
@@ -20,19 +22,19 @@ end
 namespace :test do
   task :isolated do
     test_files.all? do |file|
-      sh(Gem.ruby, '-w', '-Ilib:test', file)
-    end or raise "Failures"
+      sh(Gem.ruby, "-w", "-Ilib:test", file)
+    end || raise("Failures")
   end
 end
 
 task :lines do
-  load File.expand_path('..', File.dirname(__FILE__)) + '/tools/line_statistics'
+  load File.expand_path("..", __dir__) + "/tools/line_statistics"
   files = FileList["lib/**/*.rb"]
   CodeTools::LineStatistics.new(files).print_loc
 end
 
-rule '.rb' => '.y' do |t|
+rule ".rb" => ".y" do |t|
   sh "racc -l -o #{t.name} #{t.source}"
 end
 
-task compile: 'lib/action_dispatch/journey/parser.rb'
+task compile: "lib/action_dispatch/journey/parser.rb"
diff --git a/actionpack/actionpack.gemspec b/actionpack/actionpack.gemspec
index 965fafff5f..33d42e69d8 100644
--- a/actionpack/actionpack.gemspec
+++ b/actionpack/actionpack.gemspec
@@ -1,31 +1,38 @@
-version = File.read(File.expand_path('../../RAILS_VERSION', __FILE__)).strip
+# frozen_string_literal: true
+
+version = File.read(File.expand_path("../RAILS_VERSION", __dir__)).strip
 
 Gem::Specification.new do |s|
   s.platform    = Gem::Platform::RUBY
-  s.name        = 'actionpack'
+  s.name        = "actionpack"
   s.version     = version
-  s.summary     = 'Web-flow and rendering framework putting the VC in MVC (part of Rails).'
-  s.description = 'Web apps on Rails. Simple, battle-tested conventions for building and testing MVC web applications. Works with any Rack-compatible server.'
+  s.summary     = "Web-flow and rendering framework putting the VC in MVC (part of Rails)."
+  s.description = "Web apps on Rails. Simple, battle-tested conventions for building and testing MVC web applications. Works with any Rack-compatible server."
+
+  s.required_ruby_version = ">= 2.2.2"
 
-  s.required_ruby_version = '>= 2.2.2'
+  s.license = "MIT"
 
-  s.license = 'MIT'
+  s.author   = "David Heinemeier Hansson"
+  s.email    = "david@loudthinking.com"
+  s.homepage = "http://rubyonrails.org"
 
-  s.author   = 'David Heinemeier Hansson'
-  s.email    = 'david@loudthinking.com'
-  s.homepage = 'http://rubyonrails.org'
+  s.files        = Dir["CHANGELOG.md", "README.rdoc", "MIT-LICENSE", "lib/**/*"]
+  s.require_path = "lib"
+  s.requirements << "none"
 
-  s.files        = Dir['CHANGELOG.md', 'README.rdoc', 'MIT-LICENSE', 'lib/**/*']
-  s.require_path = 'lib'
-  s.requirements << 'none'
+  s.metadata = {
+    "source_code_uri" => "https://github.com/rails/rails/tree/v#{version}/actionpack",
+    "changelog_uri"   => "https://github.com/rails/rails/blob/v#{version}/actionpack/CHANGELOG.md"
+  }
 
-  s.add_dependency 'activesupport', version
+  s.add_dependency "activesupport", version
 
-  s.add_dependency 'rack',      '~> 2.x'
-  s.add_dependency 'rack-test', '~> 0.6.3'
-  s.add_dependency 'rails-html-sanitizer', '~> 1.0', '>= 1.0.2'
-  s.add_dependency 'rails-dom-testing', '~> 2.0'
-  s.add_dependency 'actionview', version
+  s.add_dependency "rack",      "~> 2.0"
+  s.add_dependency "rack-test", ">= 0.6.3"
+  s.add_dependency "rails-html-sanitizer", "~> 1.0", ">= 1.0.2"
+  s.add_dependency "rails-dom-testing", "~> 2.0"
+  s.add_dependency "actionview", version
 
-  s.add_development_dependency 'activemodel', version
+  s.add_development_dependency "activemodel", version
 end
diff --git a/actionpack/bin/test b/actionpack/bin/test
index 404cabba51..c53377cc97 100755
--- a/actionpack/bin/test
+++ b/actionpack/bin/test
@@ -1,4 +1,5 @@
 #!/usr/bin/env ruby
-COMPONENT_ROOT = File.expand_path("../../", __FILE__)
-require File.expand_path("../tools/test", COMPONENT_ROOT)
-exit Minitest.run(ARGV)
+# frozen_string_literal: true
+
+COMPONENT_ROOT = File.expand_path("..", __dir__)
+require_relative "../../tools/test"
diff --git a/actionpack/lib/abstract_controller.rb b/actionpack/lib/abstract_controller.rb
index 1e57cbaac4..0477e7f1c9 100644
--- a/actionpack/lib/abstract_controller.rb
+++ b/actionpack/lib/abstract_controller.rb
@@ -1,6 +1,8 @@
-require 'action_pack'
-require 'active_support/rails'
-require 'active_support/i18n'
+# frozen_string_literal: true
+
+require "action_pack"
+require "active_support/rails"
+require "active_support/i18n"
 
 module AbstractController
   extend ActiveSupport::Autoload
diff --git a/actionpack/lib/abstract_controller/asset_paths.rb b/actionpack/lib/abstract_controller/asset_paths.rb
index e6170228d9..d6ee84b87b 100644
--- a/actionpack/lib/abstract_controller/asset_paths.rb
+++ b/actionpack/lib/abstract_controller/asset_paths.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module AbstractController
   module AssetPaths #:nodoc:
     extend ActiveSupport::Concern
diff --git a/actionpack/lib/abstract_controller/base.rb b/actionpack/lib/abstract_controller/base.rb
index aa06f70433..a312af6715 100644
--- a/actionpack/lib/abstract_controller/base.rb
+++ b/actionpack/lib/abstract_controller/base.rb
@@ -1,9 +1,10 @@
-require 'erubis'
-require 'abstract_controller/error'
-require 'active_support/configurable'
-require 'active_support/descendants_tracker'
-require 'active_support/core_ext/module/anonymous'
-require 'active_support/core_ext/module/attr_internal'
+# frozen_string_literal: true
+
+require "abstract_controller/error"
+require "active_support/configurable"
+require "active_support/descendants_tracker"
+require "active_support/core_ext/module/anonymous"
+require "active_support/core_ext/module/attr_internal"
 
 module AbstractController
   # Raised when a non-existing controller action is triggered.
@@ -15,14 +16,21 @@ module AbstractController
   # expected to provide their own +render+ method, since rendering means
   # different things depending on the context.
   class Base
+    ##
+    # Returns the body of the HTTP response sent by the controller.
     attr_internal :response_body
+
+    ##
+    # Returns the name of the action this controller is processing.
     attr_internal :action_name
+
+    ##
+    # Returns the formats that can be processed by the controller.
     attr_internal :formats
 
     include ActiveSupport::Configurable
     extend ActiveSupport::DescendantsTracker
 
-    undef_method :not_implemented
     class << self
       attr_reader :abstract
       alias_method :abstract?, :abstract
@@ -94,7 +102,7 @@ module AbstractController
       # ==== Returns
       # * <tt>String</tt>
       def controller_path
-        @controller_path ||= name.sub(/Controller$/, ''.freeze).underscore unless anonymous?
+        @controller_path ||= name.sub(/Controller$/, "".freeze).underscore unless anonymous?
       end
 
       # Refresh the cached action_methods when a new action_method is added.
@@ -172,8 +180,6 @@ module AbstractController
       #
       # ==== Parameters
       # * <tt>name</tt> - The name of an action to be tested
-      #
-      # :api: private
       def action_method?(name)
         self.class.action_methods.include?(name)
       end
@@ -215,7 +221,7 @@ module AbstractController
       # ==== Returns
       # * <tt>string</tt> - The name of the method that handles the action
       # * false           - No valid method name could be found.
-      # Raise AbstractController::ActionNotFound.
+      # Raise +AbstractController::ActionNotFound+.
       def _find_action_name(action_name)
         _valid_action_name?(action_name) && method_for_action(action_name)
       end
@@ -231,11 +237,11 @@ module AbstractController
       # with a template matching the action name is considered to exist.
       #
       # If you override this method to handle additional cases, you may
-      # also provide a method (like _handle_method_missing) to handle
+      # also provide a method (like +_handle_method_missing+) to handle
       # the case.
       #
-      # If none of these conditions are true, and method_for_action
-      # returns nil, an AbstractController::ActionNotFound exception will be raised.
+      # If none of these conditions are true, and +method_for_action+
+      # returns +nil+, an +AbstractController::ActionNotFound+ exception will be raised.
       #
       # ==== Parameters
       # * <tt>action_name</tt> - An action name to find a method name for
diff --git a/actionpack/lib/abstract_controller/caching.rb b/actionpack/lib/abstract_controller/caching.rb
index 0dea50889a..ce6b757c3c 100644
--- a/actionpack/lib/abstract_controller/caching.rb
+++ b/actionpack/lib/abstract_controller/caching.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module AbstractController
   module Caching
     extend ActiveSupport::Concern
@@ -29,13 +31,15 @@ module AbstractController
       extend ConfigMethods
 
       config_accessor :default_static_extension
-      self.default_static_extension ||= '.html'
+      self.default_static_extension ||= ".html"
 
       config_accessor :perform_caching
       self.perform_caching = true if perform_caching.nil?
 
-      class_attribute :_view_cache_dependencies
-      self._view_cache_dependencies = []
+      config_accessor :enable_fragment_cache_logging
+      self.enable_fragment_cache_logging = false
+
+      class_attribute :_view_cache_dependencies, default: []
       helper_method :view_cache_dependencies if respond_to?(:helper_method)
     end
 
@@ -49,9 +53,9 @@ module AbstractController
       self.class._view_cache_dependencies.map { |dep| instance_exec(&dep) }.compact
     end
 
-    protected
+    private
       # Convenience accessor.
-      def cache(key, options = {}, &block)
+      def cache(key, options = {}, &block) # :doc:
         if cache_configured?
           cache_store.fetch(ActiveSupport::Cache.expand_cache_key(key, :controller), options, &block)
         else
diff --git a/actionpack/lib/abstract_controller/caching/fragments.rb b/actionpack/lib/abstract_controller/caching/fragments.rb
index 3257a731ed..f99b0830b2 100644
--- a/actionpack/lib/abstract_controller/caching/fragments.rb
+++ b/actionpack/lib/abstract_controller/caching/fragments.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module AbstractController
   module Caching
     # Fragment caching is used for caching various blocks within
@@ -25,7 +27,10 @@ module AbstractController
 
         self.fragment_cache_keys = []
 
-        helper_method :fragment_cache_key if respond_to?(:helper_method)
+        if respond_to?(:helper_method)
+          helper_method :fragment_cache_key
+          helper_method :combined_fragment_cache_key
+        end
       end
 
       module ClassMethods
@@ -51,7 +56,7 @@ module AbstractController
         #     end
         #   end
         def fragment_cache_key(value = nil, &key)
-          self.fragment_cache_keys += [key || ->{ value }]
+          self.fragment_cache_keys += [key || -> { value }]
         end
       end
 
@@ -62,17 +67,36 @@ module AbstractController
       # with the specified +key+ value. The key is expanded using
       # ActiveSupport::Cache.expand_cache_key.
       def fragment_cache_key(key)
+        ActiveSupport::Deprecation.warn(<<-MSG.squish)
+          Calling fragment_cache_key directly is deprecated and will be removed in Rails 6.0.
+          All fragment accessors now use the combined_fragment_cache_key method that retains the key as an array,
+          such that the caching stores can interrogate the parts for cache versions used in
+          recyclable cache keys.
+        MSG
+
         head = self.class.fragment_cache_keys.map { |k| instance_exec(&k) }
         tail = key.is_a?(Hash) ? url_for(key).split("://").last : key
         ActiveSupport::Cache.expand_cache_key([*head, *tail], :views)
       end
 
+      # Given a key (as described in +expire_fragment+), returns
+      # a key array suitable for use in reading, writing, or expiring a
+      # cached fragment. All keys begin with <tt>:views</tt>,
+      # followed by ENV["RAILS_CACHE_ID"] or ENV["RAILS_APP_VERSION"] if set,
+      # followed by any controller-wide key prefix values, ending
+      # with the specified +key+ value.
+      def combined_fragment_cache_key(key)
+        head = self.class.fragment_cache_keys.map { |k| instance_exec(&k) }
+        tail = key.is_a?(Hash) ? url_for(key).split("://").last : key
+        [ :views, (ENV["RAILS_CACHE_ID"] || ENV["RAILS_APP_VERSION"]), *head, *tail ].compact
+      end
+
       # Writes +content+ to the location signified by
       # +key+ (see +expire_fragment+ for acceptable formats).
       def write_fragment(key, content, options = nil)
         return content unless cache_configured?
 
-        key = fragment_cache_key(key)
+        key = combined_fragment_cache_key(key)
         instrument_fragment_cache :write_fragment, key do
           content = content.to_str
           cache_store.write(key, content, options)
@@ -85,7 +109,7 @@ module AbstractController
       def read_fragment(key, options = nil)
         return unless cache_configured?
 
-        key = fragment_cache_key(key)
+        key = combined_fragment_cache_key(key)
         instrument_fragment_cache :read_fragment, key do
           result = cache_store.read(key, options)
           result.respond_to?(:html_safe) ? result.html_safe : result
@@ -96,7 +120,7 @@ module AbstractController
       # +key+ exists (see +expire_fragment+ for acceptable formats).
       def fragment_exist?(key, options = nil)
         return unless cache_configured?
-        key = fragment_cache_key(key)
+        key = combined_fragment_cache_key(key)
 
         instrument_fragment_cache :exist_fragment?, key do
           cache_store.exist?(key, options)
@@ -123,7 +147,7 @@ module AbstractController
       # method (or <tt>delete_matched</tt>, for Regexp keys).
       def expire_fragment(key, options = nil)
         return unless cache_configured?
-        key = fragment_cache_key(key) unless key.is_a?(Regexp)
+        key = combined_fragment_cache_key(key) unless key.is_a?(Regexp)
 
         instrument_fragment_cache :expire_fragment, key do
           if key.is_a?(Regexp)
@@ -135,8 +159,7 @@ module AbstractController
       end
 
       def instrument_fragment_cache(name, key) # :nodoc:
-        payload = instrument_payload(key)
-        ActiveSupport::Notifications.instrument("#{name}.#{instrument_name}", payload) { yield }
+        ActiveSupport::Notifications.instrument("#{name}.#{instrument_name}", instrument_payload(key)) { yield }
       end
     end
   end
diff --git a/actionpack/lib/abstract_controller/callbacks.rb b/actionpack/lib/abstract_controller/callbacks.rb
index 3ef8da86fa..146d17cf40 100644
--- a/actionpack/lib/abstract_controller/callbacks.rb
+++ b/actionpack/lib/abstract_controller/callbacks.rb
@@ -1,4 +1,26 @@
+# frozen_string_literal: true
+
 module AbstractController
+  # = Abstract Controller Callbacks
+  #
+  # Abstract Controller provides hooks during the life cycle of a controller action.
+  # Callbacks allow you to trigger logic during this cycle. Available callbacks are:
+  #
+  # * <tt>after_action</tt>
+  # * <tt>append_after_action</tt>
+  # * <tt>append_around_action</tt>
+  # * <tt>append_before_action</tt>
+  # * <tt>around_action</tt>
+  # * <tt>before_action</tt>
+  # * <tt>prepend_after_action</tt>
+  # * <tt>prepend_around_action</tt>
+  # * <tt>prepend_before_action</tt>
+  # * <tt>skip_after_action</tt>
+  # * <tt>skip_around_action</tt>
+  # * <tt>skip_before_action</tt>
+  #
+  # NOTE: Calling the same callback multiple times will overwrite previous callback definitions.
+  #
   module Callbacks
     extend ActiveSupport::Concern
 
@@ -9,12 +31,12 @@ module AbstractController
 
     included do
       define_callbacks :process_action,
-                       terminator: ->(controller, result_lambda) { result_lambda.call if result_lambda.is_a?(Proc); controller.performed? },
+                       terminator: ->(controller, result_lambda) { result_lambda.call; controller.performed? },
                        skip_after_callbacks_if_terminated: true
     end
 
-    # Override AbstractController::Base's process_action to run the
-    # process_action callbacks around the normal behavior.
+    # Override <tt>AbstractController::Base#process_action</tt> to run the
+    # <tt>process_action</tt> callbacks around the normal behavior.
     def process_action(*args)
       run_callbacks(:process_action) do
         super
@@ -49,30 +71,11 @@ module AbstractController
       def _normalize_callback_option(options, from, to) # :nodoc:
         if from = options[from]
           _from = Array(from).map(&:to_s).to_set
-          from = proc {|c| _from.include? c.action_name }
+          from = proc { |c| _from.include? c.action_name }
           options[to] = Array(options[to]).unshift(from)
         end
       end
 
-      # Skip before, after, and around action callbacks matching any of the names.
-      #
-      # ==== Parameters
-      # * <tt>names</tt> - A list of valid names that could be used for
-      #   callbacks. Note that skipping uses Ruby equality, so it's
-      #   impossible to skip a callback defined using an anonymous proc
-      #   using #skip_action_callback.
-      def skip_action_callback(*names)
-        ActiveSupport::Deprecation.warn('`skip_action_callback` is deprecated and will be removed in Rails 5.1. Please use skip_before_action, skip_after_action or skip_around_action instead.')
-        skip_before_action(*names, raise: false)
-        skip_after_action(*names, raise: false)
-        skip_around_action(*names, raise: false)
-      end
-
-      def skip_filter(*names)
-        ActiveSupport::Deprecation.warn("`skip_filter` is deprecated and will be removed in Rails 5.1. Use skip_before_action, skip_after_action or skip_around_action instead.")
-        skip_action_callback(*names)
-      end
-
       # Take callback names and an optional callback proc, normalize them,
       # then call the block with each callback. This allows us to abstract
       # the normalization across several methods that use it.
@@ -187,22 +190,12 @@ module AbstractController
           end
         end
 
-        define_method "#{callback}_filter" do |*names, &blk|
-          ActiveSupport::Deprecation.warn("#{callback}_filter is deprecated and will be removed in Rails 5.1. Use #{callback}_action instead.")
-          send("#{callback}_action", *names, &blk)
-        end
-
         define_method "prepend_#{callback}_action" do |*names, &blk|
           _insert_callbacks(names, blk) do |name, options|
-            set_callback(:process_action, callback, name, options.merge(:prepend => true))
+            set_callback(:process_action, callback, name, options.merge(prepend: true))
           end
         end
 
-        define_method "prepend_#{callback}_filter" do |*names, &blk|
-          ActiveSupport::Deprecation.warn("prepend_#{callback}_filter is deprecated and will be removed in Rails 5.1. Use prepend_#{callback}_action instead.")
-          send("prepend_#{callback}_action", *names, &blk)
-        end
-
         # Skip a before, after or around callback. See _insert_callbacks
         # for details on the allowed parameters.
         define_method "skip_#{callback}_action" do |*names|
@@ -211,18 +204,8 @@ module AbstractController
           end
         end
 
-        define_method "skip_#{callback}_filter" do |*names, &blk|
-          ActiveSupport::Deprecation.warn("skip_#{callback}_filter is deprecated and will be removed in Rails 5.1. Use skip_#{callback}_action instead.")
-          send("skip_#{callback}_action", *names, &blk)
-        end
-
         # *_action is the same as append_*_action
         alias_method :"append_#{callback}_action", :"#{callback}_action"
-
-        define_method "append_#{callback}_filter" do |*names, &blk|
-          ActiveSupport::Deprecation.warn("append_#{callback}_filter is deprecated and will be removed in Rails 5.1. Use append_#{callback}_action instead.")
-          send("append_#{callback}_action", *names, &blk)
-        end
       end
     end
   end
diff --git a/actionpack/lib/abstract_controller/collector.rb b/actionpack/lib/abstract_controller/collector.rb
index 55654be224..297ec5ca40 100644
--- a/actionpack/lib/abstract_controller/collector.rb
+++ b/actionpack/lib/abstract_controller/collector.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require "action_dispatch/http/mime_type"
 
 module AbstractController
@@ -16,10 +18,10 @@ module AbstractController
     end
 
     Mime::Type.register_callback do |mime|
-      generate_method_for_mime(mime) unless self.instance_methods.include?(mime.to_sym)
+      generate_method_for_mime(mime) unless instance_methods.include?(mime.to_sym)
     end
 
-  protected
+  private
 
     def method_missing(symbol, &block)
       unless mime_constant = Mime[symbol]
diff --git a/actionpack/lib/abstract_controller/error.rb b/actionpack/lib/abstract_controller/error.rb
index 7fafce4dd4..89a54f072e 100644
--- a/actionpack/lib/abstract_controller/error.rb
+++ b/actionpack/lib/abstract_controller/error.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module AbstractController
   class Error < StandardError #:nodoc:
   end
diff --git a/actionpack/lib/abstract_controller/helpers.rb b/actionpack/lib/abstract_controller/helpers.rb
index ab4355296b..35b462bc92 100644
--- a/actionpack/lib/abstract_controller/helpers.rb
+++ b/actionpack/lib/abstract_controller/helpers.rb
@@ -1,15 +1,14 @@
-require 'active_support/dependencies'
+# frozen_string_literal: true
+
+require "active_support/dependencies"
 
 module AbstractController
   module Helpers
     extend ActiveSupport::Concern
 
     included do
-      class_attribute :_helpers
-      self._helpers = Module.new
-
-      class_attribute :_helper_methods
-      self._helper_methods = Array.new
+      class_attribute :_helpers, default: Module.new
+      class_attribute :_helper_methods, default: Array.new
     end
 
     class MissingHelperError < LoadError
@@ -171,25 +170,25 @@ module AbstractController
       end
 
       private
-      # Makes all the (instance) methods in the helper module available to templates
-      # rendered through this controller.
-      #
-      # ==== Parameters
-      # * <tt>module</tt> - The module to include into the current helper module
-      #   for the class
-      def add_template_helper(mod)
-        _helpers.module_eval { include mod }
-      end
+        # Makes all the (instance) methods in the helper module available to templates
+        # rendered through this controller.
+        #
+        # ==== Parameters
+        # * <tt>module</tt> - The module to include into the current helper module
+        #   for the class
+        def add_template_helper(mod)
+          _helpers.module_eval { include mod }
+        end
 
-      def default_helper_module!
-        module_name = name.sub(/Controller$/, ''.freeze)
-        module_path = module_name.underscore
-        helper module_path
-      rescue LoadError => e
-        raise e unless e.is_missing? "helpers/#{module_path}_helper"
-      rescue NameError => e
-        raise e unless e.missing_name? "#{module_name}Helper"
-      end
+        def default_helper_module!
+          module_name = name.sub(/Controller$/, "".freeze)
+          module_path = module_name.underscore
+          helper module_path
+        rescue LoadError => e
+          raise e unless e.is_missing? "helpers/#{module_path}_helper"
+        rescue NameError => e
+          raise e unless e.missing_name? "#{module_name}Helper"
+        end
     end
   end
 end
diff --git a/actionpack/lib/abstract_controller/logger.rb b/actionpack/lib/abstract_controller/logger.rb
index c31ea6c5b5..8d0acc1b5c 100644
--- a/actionpack/lib/abstract_controller/logger.rb
+++ b/actionpack/lib/abstract_controller/logger.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require "active_support/benchmarkable"
 
 module AbstractController
diff --git a/actionpack/lib/abstract_controller/railties/routes_helpers.rb b/actionpack/lib/abstract_controller/railties/routes_helpers.rb
index 14b574e322..b6e5631a4e 100644
--- a/actionpack/lib/abstract_controller/railties/routes_helpers.rb
+++ b/actionpack/lib/abstract_controller/railties/routes_helpers.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module AbstractController
   module Railties
     module RoutesHelpers
diff --git a/actionpack/lib/abstract_controller/rendering.rb b/actionpack/lib/abstract_controller/rendering.rb
index 4ba2c26949..8ba2b25552 100644
--- a/actionpack/lib/abstract_controller/rendering.rb
+++ b/actionpack/lib/abstract_controller/rendering.rb
@@ -1,9 +1,9 @@
-require 'abstract_controller/error'
-require 'active_support/concern'
-require 'active_support/core_ext/class/attribute'
-require 'action_view'
-require 'action_view/view_paths'
-require 'set'
+# frozen_string_literal: true
+
+require "abstract_controller/error"
+require "action_view"
+require "action_view/view_paths"
+require "set"
 
 module AbstractController
   class DoubleRenderError < Error
@@ -20,7 +20,6 @@ module AbstractController
 
     # Normalizes arguments, options and then delegates render_to_body and
     # sticks the result in <tt>self.response_body</tt>.
-    # :api: public
     def render(*args, &block)
       options = _normalize_render(*args, &block)
       rendered_body = render_to_body(options)
@@ -42,19 +41,16 @@ module AbstractController
     # (as ActionController extends it to be anything that
     # responds to the method each), this method needs to be
     # overridden in order to still return a string.
-    # :api: plugin
     def render_to_string(*args, &block)
       options = _normalize_render(*args, &block)
       render_to_body(options)
     end
 
     # Performs the actual template rendering.
-    # :api: public
     def render_to_body(options = {})
     end
 
-    # Returns Content-Type of rendered content
-    # :api: public
+    # Returns Content-Type of rendered content.
     def rendered_format
       Mime[:text]
     end
@@ -65,7 +61,6 @@ module AbstractController
 
     # This method should return a hash with assigns.
     # You can overwrite this configuration per controller.
-    # :api: public
     def view_assigns
       protected_vars = _protected_ivars
       variables      = instance_variables
@@ -76,11 +71,11 @@ module AbstractController
       }
     end
 
+  private
     # Normalize args by converting <tt>render "foo"</tt> to
     # <tt>render :action => "foo"</tt> and <tt>render "foo/bar"</tt> to
     # <tt>render :file => "foo/bar"</tt>.
-    # :api: plugin
-    def _normalize_args(action=nil, options={})
+    def _normalize_args(action = nil, options = {}) # :doc:
       if action.respond_to?(:permitted?)
         if action.permitted?
           action
@@ -95,20 +90,20 @@ module AbstractController
     end
 
     # Normalize options.
-    # :api: plugin
-    def _normalize_options(options)
+    def _normalize_options(options) # :doc:
       options
     end
 
     # Process extra options.
-    # :api: plugin
-    def _process_options(options)
+    def _process_options(options) # :doc:
       options
     end
 
     # Process the rendered format.
-    # :api: private
-    def _process_format(format)
+    def _process_format(format) # :nodoc:
+    end
+
+    def _process_variant(options)
     end
 
     def _set_html_content_type # :nodoc:
@@ -118,13 +113,9 @@ module AbstractController
     end
 
     # Normalize args and options.
-    # :api: private
-    def _normalize_render(*args, &block)
+    def _normalize_render(*args, &block) # :nodoc:
       options = _normalize_args(*args, &block)
-      #TODO: remove defined? when we restore AP <=> AV dependency
-      if defined?(request) && !request.nil? && request.variant.present?
-        options[:variant] = request.variant
-      end
+      _process_variant(options)
       _normalize_options(options)
       options
     end
diff --git a/actionpack/lib/abstract_controller/translation.rb b/actionpack/lib/abstract_controller/translation.rb
index 56b8ce895e..666e154e4c 100644
--- a/actionpack/lib/abstract_controller/translation.rb
+++ b/actionpack/lib/abstract_controller/translation.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module AbstractController
   module Translation
     # Delegates to <tt>I18n.translate</tt>. Also aliased as <tt>t</tt>.
@@ -9,11 +11,11 @@ module AbstractController
     # to translate many keys within the same controller / action and gives you a
     # simple framework for scoping them consistently.
     def translate(key, options = {})
-      if key.to_s.first == '.'
-        path = controller_path.tr('/', '.')
+      if key.to_s.first == "."
+        path = controller_path.tr("/", ".")
         defaults = [:"#{path}#{key}"]
         defaults << options[:default] if options[:default]
-        options[:default] = defaults
+        options[:default] = defaults.flatten
         key = "#{path}.#{action_name}#{key}"
       end
       I18n.translate(key, options)
diff --git a/actionpack/lib/abstract_controller/url_for.rb b/actionpack/lib/abstract_controller/url_for.rb
index 72d07b0927..bd74c27d3b 100644
--- a/actionpack/lib/abstract_controller/url_for.rb
+++ b/actionpack/lib/abstract_controller/url_for.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module AbstractController
   # Includes +url_for+ into the host class (e.g. an abstract controller or mailer). The class
   # has to provide a +RouteSet+ by implementing the <tt>_routes</tt> methods. Otherwise, an
diff --git a/actionpack/lib/action_controller.rb b/actionpack/lib/action_controller.rb
index 62f5905205..f43784f9f2 100644
--- a/actionpack/lib/action_controller.rb
+++ b/actionpack/lib/action_controller.rb
@@ -1,8 +1,10 @@
-require 'active_support/rails'
-require 'abstract_controller'
-require 'action_dispatch'
-require 'action_controller/metal/live'
-require 'action_controller/metal/strong_parameters'
+# frozen_string_literal: true
+
+require "active_support/rails"
+require "abstract_controller"
+require "action_dispatch"
+require "action_controller/metal/live"
+require "action_controller/metal/strong_parameters"
 
 module ActionController
   extend ActiveSupport::Autoload
@@ -20,9 +22,11 @@ module ActionController
 
   autoload_under "metal" do
     autoload :ConditionalGet
+    autoload :ContentSecurityPolicy
     autoload :Cookies
     autoload :DataStreaming
     autoload :EtagWithTemplateDigest
+    autoload :EtagWithFlash
     autoload :Flash
     autoload :ForceSSL
     autoload :Head
@@ -40,6 +44,7 @@ module ActionController
     autoload :Rescue
     autoload :Streaming
     autoload :StrongParameters
+    autoload :ParameterEncoding
     autoload :Testing
     autoload :UrlFor
   end
@@ -48,14 +53,14 @@ module ActionController
     autoload :ApiRendering
   end
 
-  autoload :TestCase,           'action_controller/test_case'
-  autoload :TemplateAssertions, 'action_controller/test_case'
+  autoload :TestCase,           "action_controller/test_case"
+  autoload :TemplateAssertions, "action_controller/test_case"
 end
 
 # Common Active Support usage in Action Controller
-require 'active_support/core_ext/module/attribute_accessors'
-require 'active_support/core_ext/load_error'
-require 'active_support/core_ext/module/attr_internal'
-require 'active_support/core_ext/name_error'
-require 'active_support/core_ext/uri'
-require 'active_support/inflector'
+require "active_support/core_ext/module/attribute_accessors"
+require "active_support/core_ext/load_error"
+require "active_support/core_ext/module/attr_internal"
+require "active_support/core_ext/name_error"
+require "active_support/core_ext/uri"
+require "active_support/inflector"
diff --git a/actionpack/lib/action_controller/api.rb b/actionpack/lib/action_controller/api.rb
index 6bbebb7b4c..b192e496de 100644
--- a/actionpack/lib/action_controller/api.rb
+++ b/actionpack/lib/action_controller/api.rb
@@ -1,6 +1,8 @@
-require 'action_view'
-require 'action_controller'
-require 'action_controller/log_subscriber'
+# frozen_string_literal: true
+
+require "action_view"
+require "action_controller"
+require "action_controller/log_subscriber"
 
 module ActionController
   # API Controller is a lightweight version of <tt>ActionController::Base</tt>,
@@ -81,10 +83,9 @@ module ActionController
   #     end
   #   end
   #
-  # Quite straightforward. Make sure to check the modules included in
-  # <tt>ActionController::Base</tt> if you want to use any other
-  # functionality that is not provided by <tt>ActionController::API</tt>
-  # out of the box.
+  # Make sure to check the modules included in <tt>ActionController::Base</tt>
+  # if you want to use any other functionality that is not provided
+  # by <tt>ActionController::API</tt> out of the box.
   class API < Metal
     abstract!
 
@@ -142,6 +143,7 @@ module ActionController
       include mod
     end
 
+    ActiveSupport.run_load_hooks(:action_controller_api, self)
     ActiveSupport.run_load_hooks(:action_controller, self)
   end
 end
diff --git a/actionpack/lib/action_controller/api/api_rendering.rb b/actionpack/lib/action_controller/api/api_rendering.rb
index 3a08d28c39..aca5265313 100644
--- a/actionpack/lib/action_controller/api/api_rendering.rb
+++ b/actionpack/lib/action_controller/api/api_rendering.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActionController
   module ApiRendering
     extend ActiveSupport::Concern
diff --git a/actionpack/lib/action_controller/base.rb b/actionpack/lib/action_controller/base.rb
index d546d7260c..204a3d400c 100644
--- a/actionpack/lib/action_controller/base.rb
+++ b/actionpack/lib/action_controller/base.rb
@@ -1,4 +1,6 @@
-require 'action_view'
+# frozen_string_literal: true
+
+require "action_view"
 require "action_controller/log_subscriber"
 require "action_controller/metal/params_wrapper"
 
@@ -8,7 +10,7 @@ module ActionController
   # on the controller, which will automatically be made accessible to the web-server through \Rails Routes.
   #
   # By default, only the ApplicationController in a \Rails application inherits from <tt>ActionController::Base</tt>. All other
-  # controllers in turn inherit from ApplicationController. This gives you one class to configure things such as
+  # controllers inherit from ApplicationController. This gives you one class to configure things such as
   # request forgery protection and filtering of sensitive request parameters.
   #
   # A sample controller could look like this:
@@ -30,9 +32,9 @@ module ActionController
   #
   # Unlike index, the create action will not render a template. After performing its main purpose (creating a
   # new post), it initiates a redirect instead. This redirect works by returning an external
-  # "302 Moved" HTTP response that takes the user to the index action.
+  # <tt>302 Moved</tt> HTTP response that takes the user to the index action.
   #
-  # These two methods represent the two basic action archetypes used in Action Controllers. Get-and-show and do-and-redirect.
+  # These two methods represent the two basic action archetypes used in Action Controllers: Get-and-show and do-and-redirect.
   # Most actions are variations on these themes.
   #
   # == Requests
@@ -51,16 +53,16 @@ module ActionController
   # == Parameters
   #
   # All request parameters, whether they come from a query string in the URL or form data submitted through a POST request are
-  # available through the params method which returns a hash. For example, an action that was performed through
-  # <tt>/posts?category=All&limit=5</tt> will include <tt>{ "category" => "All", "limit" => "5" }</tt> in params.
+  # available through the <tt>params</tt> method which returns a hash. For example, an action that was performed through
+  # <tt>/posts?category=All&limit=5</tt> will include <tt>{ "category" => "All", "limit" => "5" }</tt> in <tt>params</tt>.
   #
   # It's also possible to construct multi-dimensional parameter hashes by specifying keys using brackets, such as:
   #
   #   <input type="text" name="post[name]" value="david">
   #   <input type="text" name="post[address]" value="hyacintvej">
   #
-  # A request stemming from a form holding these inputs will include <tt>{ "post" => { "name" => "david", "address" => "hyacintvej" } }</tt>.
-  # If the address input had been named <tt>post[address][street]</tt>, the params would have included
+  # A request coming from a form holding these inputs will include <tt>{ "post" => { "name" => "david", "address" => "hyacintvej" } }</tt>.
+  # If the address input had been named <tt>post[address][street]</tt>, the <tt>params</tt> would have included
   # <tt>{ "post" => { "address" => { "street" => "hyacintvej" } } }</tt>. There's no limit to the depth of the nesting.
   #
   # == Sessions
@@ -74,7 +76,7 @@ module ActionController
   #
   #   session[:person] = Person.authenticate(user_name, password)
   #
-  # And retrieved again through the same hash:
+  # You can retrieve it again through the same hash:
   #
   #   Hello #{session[:person]}
   #
@@ -213,15 +215,17 @@ module ActionController
       Renderers::All,
       ConditionalGet,
       EtagWithTemplateDigest,
+      EtagWithFlash,
       Caching,
       MimeResponds,
       ImplicitRender,
       StrongParameters,
-
+      ParameterEncoding,
       Cookies,
       Flash,
       FormBuilder,
       RequestForgeryProtection,
+      ContentSecurityPolicy,
       ForceSSL,
       Streaming,
       DataStreaming,
@@ -260,6 +264,13 @@ module ActionController
       PROTECTED_IVARS
     end
 
+    def self.make_response!(request)
+      ActionDispatch::Response.create.tap do |res|
+        res.request = request
+      end
+    end
+
+    ActiveSupport.run_load_hooks(:action_controller_base, self)
     ActiveSupport.run_load_hooks(:action_controller, self)
   end
 end
diff --git a/actionpack/lib/action_controller/caching.rb b/actionpack/lib/action_controller/caching.rb
index a9a8508abc..97775d1dc8 100644
--- a/actionpack/lib/action_controller/caching.rb
+++ b/actionpack/lib/action_controller/caching.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActionController
   # \Caching is a cheap way of speeding up slow applications by keeping the result of
   # calculations, renderings, and database calls around for subsequent requests.
@@ -38,7 +40,7 @@ module ActionController
       end
 
       def instrument_name
-        "action_controller"
+        "action_controller".freeze
       end
   end
 end
diff --git a/actionpack/lib/action_controller/form_builder.rb b/actionpack/lib/action_controller/form_builder.rb
index f2656ca894..09d2ac1837 100644
--- a/actionpack/lib/action_controller/form_builder.rb
+++ b/actionpack/lib/action_controller/form_builder.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActionController
   # Override the default form builder for all views rendered by this
   # controller and any of its descendants. Accepts a subclass of
diff --git a/actionpack/lib/action_controller/log_subscriber.rb b/actionpack/lib/action_controller/log_subscriber.rb
index a0917b4fdb..14f41eb55f 100644
--- a/actionpack/lib/action_controller/log_subscriber.rb
+++ b/actionpack/lib/action_controller/log_subscriber.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActionController
   class LogSubscriber < ActiveSupport::LogSubscriber
     INTERNAL_PARAMS = %w(controller action format _method only_path)
@@ -24,7 +26,7 @@ module ActionController
           exception_class_name = payload[:exception].first
           status = ActionDispatch::ExceptionWrapper.status_code_for_exception(exception_class_name)
         end
-        message = "Completed #{status} #{Rack::Utils::HTTP_STATUS_CODES[status]} in #{event.duration.round}ms"
+        message = "Completed #{status} #{Rack::Utils::HTTP_STATUS_CODES[status]} in #{event.duration.round}ms".dup
         message << " (#{additions.join(" | ".freeze)})" unless additions.empty?
         message << "\n\n" if defined?(Rails.env) && Rails.env.development?
 
@@ -51,7 +53,7 @@ module ActionController
     def unpermitted_parameters(event)
       debug do
         unpermitted_keys = event.payload[:keys]
-        "Unpermitted parameter#{'s' if unpermitted_keys.size > 1}: #{unpermitted_keys.join(", ")}"
+        "Unpermitted parameter#{'s' if unpermitted_keys.size > 1}: #{unpermitted_keys.map { |e| ":#{e}" }.join(", ")}"
       end
     end
 
@@ -59,10 +61,10 @@ module ActionController
        expire_fragment expire_page write_page).each do |method|
       class_eval <<-METHOD, __FILE__, __LINE__ + 1
         def #{method}(event)
-          return unless logger.info?
-          key_or_path = event.payload[:key] || event.payload[:path]
+          return unless logger.info? && ActionController::Base.enable_fragment_cache_logging
+          key         = ActiveSupport::Cache.expand_cache_key(event.payload[:key] || event.payload[:path])
           human_name  = #{method.to_s.humanize.inspect}
-          info("\#{human_name} \#{key_or_path} (\#{event.duration.round(1)}ms)")
+          info("\#{human_name} \#{key} (\#{event.duration.round(1)}ms)")
         end
       METHOD
     end
diff --git a/actionpack/lib/action_controller/metal.rb b/actionpack/lib/action_controller/metal.rb
index f6e67b02d7..457884ea08 100644
--- a/actionpack/lib/action_controller/metal.rb
+++ b/actionpack/lib/action_controller/metal.rb
@@ -1,7 +1,9 @@
-require 'active_support/core_ext/array/extract_options'
-require 'action_dispatch/middleware/stack'
-require 'action_dispatch/http/request'
-require 'action_dispatch/http/response'
+# frozen_string_literal: true
+
+require "active_support/core_ext/array/extract_options"
+require "action_dispatch/middleware/stack"
+require "action_dispatch/http/request"
+require "action_dispatch/http/response"
 
 module ActionController
   # Extend ActionDispatch middleware stack to make it aware of options
@@ -34,29 +36,29 @@ module ActionController
 
     private
 
-    INCLUDE = ->(list, action) { list.include? action }
-    EXCLUDE = ->(list, action) { !list.include? action }
-    NULL    = ->(list, action) { true }
-
-    def build_middleware(klass, args, block)
-      options = args.extract_options!
-      only   = Array(options.delete(:only)).map(&:to_s)
-      except = Array(options.delete(:except)).map(&:to_s)
-      args << options unless options.empty?
-
-      strategy = NULL
-      list     = nil
-
-      if only.any?
-        strategy = INCLUDE
-        list     = only
-      elsif except.any?
-        strategy = EXCLUDE
-        list     = except
-      end
+      INCLUDE = ->(list, action) { list.include? action }
+      EXCLUDE = ->(list, action) { !list.include? action }
+      NULL    = ->(list, action) { true }
+
+      def build_middleware(klass, args, block)
+        options = args.extract_options!
+        only   = Array(options.delete(:only)).map(&:to_s)
+        except = Array(options.delete(:except)).map(&:to_s)
+        args << options unless options.empty?
+
+        strategy = NULL
+        list     = nil
+
+        if only.any?
+          strategy = INCLUDE
+          list     = only
+        elsif except.any?
+          strategy = EXCLUDE
+          list     = except
+        end
 
-      Middleware.new(get_class(klass), args, list, strategy, block)
-    end
+        Middleware.new(klass, args, list, strategy, block)
+      end
   end
 
   # <tt>ActionController::Metal</tt> is the simplest possible controller, providing a
@@ -118,11 +120,6 @@ module ActionController
   class Metal < AbstractController::Base
     abstract!
 
-    def env
-      @_request.env
-    end
-    deprecate :env
-
     # Returns the last part of the controller's name, underscored, without the ending
     # <tt>Controller</tt>. For instance, PostsController returns <tt>posts</tt>.
     # Namespaces are left out, so Admin::PostsController returns <tt>posts</tt> as well.
@@ -130,24 +127,28 @@ module ActionController
     # ==== Returns
     # * <tt>string</tt>
     def self.controller_name
-      @controller_name ||= name.demodulize.sub(/Controller$/, '').underscore
+      @controller_name ||= name.demodulize.sub(/Controller$/, "").underscore
     end
 
     def self.make_response!(request)
-      ActionDispatch::Response.create.tap do |res|
+      ActionDispatch::Response.new.tap do |res|
         res.request = request
       end
     end
 
-    # Delegates to the class' <tt>controller_name</tt>
+    def self.binary_params_for?(action) # :nodoc:
+      false
+    end
+
+    # Delegates to the class' <tt>controller_name</tt>.
     def controller_name
       self.class.controller_name
     end
 
     attr_internal :response, :request
-    delegate :session, :to => "@_request"
+    delegate :session, to: "@_request"
     delegate :headers, :status=, :location=, :content_type=,
-             :status, :location, :content_type, :to => "@_response"
+             :status, :location, :content_type, to: "@_response"
 
     def initialize
       @_request = nil
@@ -209,8 +210,7 @@ module ActionController
       @_request.reset_session
     end
 
-    class_attribute :middleware_stack
-    self.middleware_stack = ActionController::MiddlewareStack.new
+    class_attribute :middleware_stack, default: ActionController::MiddlewareStack.new
 
     def self.inherited(base) # :nodoc:
       base.middleware_stack = middleware_stack.dup
@@ -228,14 +228,6 @@ module ActionController
       middleware_stack
     end
 
-    # Makes the controller a Rack endpoint that runs the action in the given
-    # +env+'s +action_dispatch.request.path_parameters+ key.
-    def self.call(env)
-      req = ActionDispatch::Request.new env
-      action(req.path_parameters[:action]).call(env)
-    end
-    class << self; deprecate :call; end
-
     # Returns a Rack endpoint for the given action name.
     def self.action(name)
       if middleware_stack.any?
@@ -253,7 +245,7 @@ module ActionController
       end
     end
 
-    # Direct dispatch to the controller.  Instantiates the controller, then
+    # Direct dispatch to the controller. Instantiates the controller, then
     # executes the action named +name+.
     def self.dispatch(name, req, res)
       if middleware_stack.any?
diff --git a/actionpack/lib/action_controller/metal/basic_implicit_render.rb b/actionpack/lib/action_controller/metal/basic_implicit_render.rb
index cef65a362c..2dc990f303 100644
--- a/actionpack/lib/action_controller/metal/basic_implicit_render.rb
+++ b/actionpack/lib/action_controller/metal/basic_implicit_render.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActionController
   module BasicImplicitRender # :nodoc:
     def send_action(method, *args)
diff --git a/actionpack/lib/action_controller/metal/conditional_get.rb b/actionpack/lib/action_controller/metal/conditional_get.rb
index e21449f376..06b6a95ff8 100644
--- a/actionpack/lib/action_controller/metal/conditional_get.rb
+++ b/actionpack/lib/action_controller/metal/conditional_get.rb
@@ -1,4 +1,6 @@
-require 'active_support/core_ext/hash/keys'
+# frozen_string_literal: true
+
+require "active_support/core_ext/hash/keys"
 
 module ActionController
   module ConditionalGet
@@ -7,8 +9,7 @@ module ActionController
     include Head
 
     included do
-      class_attribute :etaggers
-      self.etaggers = []
+      class_attribute :etaggers, default: []
     end
 
     module ClassMethods
@@ -227,25 +228,26 @@ module ActionController
     #   expires_in 3.hours, public: true, must_revalidate: true
     #
     # This method will overwrite an existing Cache-Control header.
-    # See http://www.w3.org/Protocols/rfc2616/rfc2616-sec14.html for more possibilities.
+    # See https://www.w3.org/Protocols/rfc2616/rfc2616-sec14.html for more possibilities.
     #
     # The method will also ensure an HTTP Date header for client compatibility.
     def expires_in(seconds, options = {})
       response.cache_control.merge!(
-        :max_age         => seconds,
-        :public          => options.delete(:public),
-        :must_revalidate => options.delete(:must_revalidate)
+        max_age: seconds,
+        public: options.delete(:public),
+        must_revalidate: options.delete(:must_revalidate)
       )
       options.delete(:private)
 
-      response.cache_control[:extras] = options.map {|k,v| "#{k}=#{v}"}
+      response.cache_control[:extras] = options.map { |k, v| "#{k}=#{v}" }
       response.date = Time.now unless response.date?
     end
 
-    # Sets an HTTP 1.1 Cache-Control header of <tt>no-cache</tt> so no caching should
-    # occur by the browser or intermediate caches (like caching proxy servers).
+    # Sets an HTTP 1.1 Cache-Control header of <tt>no-cache</tt>. This means the
+    # resource will be marked as stale, so clients must always revalidate.
+    # Intermediate/browser caches may still store the asset.
     def expires_now
-      response.cache_control.replace(:no_cache => true)
+      response.cache_control.replace(no_cache: true)
     end
 
     # Cache or yield the block. The cache is supposed to never expire.
diff --git a/actionpack/lib/action_controller/metal/content_security_policy.rb b/actionpack/lib/action_controller/metal/content_security_policy.rb
new file mode 100644
index 0000000000..48a7109bea
--- /dev/null
+++ b/actionpack/lib/action_controller/metal/content_security_policy.rb
@@ -0,0 +1,26 @@
+# frozen_string_literal: true
+
+module ActionController #:nodoc:
+  module ContentSecurityPolicy
+    # TODO: Documentation
+    extend ActiveSupport::Concern
+
+    module ClassMethods
+      def content_security_policy(**options, &block)
+        before_action(options) do
+          if block_given?
+            policy = request.content_security_policy.clone
+            yield policy
+            request.content_security_policy = policy
+          end
+        end
+      end
+
+      def content_security_policy_report_only(report_only = true, **options)
+        before_action(options) do
+          request.content_security_policy_report_only = report_only
+        end
+      end
+    end
+  end
+end
diff --git a/actionpack/lib/action_controller/metal/cookies.rb b/actionpack/lib/action_controller/metal/cookies.rb
index 44925641a1..ff46966693 100644
--- a/actionpack/lib/action_controller/metal/cookies.rb
+++ b/actionpack/lib/action_controller/metal/cookies.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActionController #:nodoc:
   module Cookies
     extend ActiveSupport::Concern
diff --git a/actionpack/lib/action_controller/metal/data_streaming.rb b/actionpack/lib/action_controller/metal/data_streaming.rb
index 6cd6130032..5a82ccf668 100644
--- a/actionpack/lib/action_controller/metal/data_streaming.rb
+++ b/actionpack/lib/action_controller/metal/data_streaming.rb
@@ -1,4 +1,6 @@
-require 'action_controller/metal/exceptions'
+# frozen_string_literal: true
+
+require "action_controller/metal/exceptions"
 
 module ActionController #:nodoc:
   # Methods for sending arbitrary data and for streaming files to the browser,
@@ -8,10 +10,10 @@ module ActionController #:nodoc:
 
     include ActionController::Rendering
 
-    DEFAULT_SEND_FILE_TYPE        = 'application/octet-stream'.freeze #:nodoc:
-    DEFAULT_SEND_FILE_DISPOSITION = 'attachment'.freeze #:nodoc:
+    DEFAULT_SEND_FILE_TYPE        = "application/octet-stream".freeze #:nodoc:
+    DEFAULT_SEND_FILE_DISPOSITION = "attachment".freeze #:nodoc:
 
-    protected
+    private
       # Sends the file. This uses a server-appropriate method (such as X-Sendfile)
       # via the Rack::Sendfile middleware. The header to use is set via
       # +config.action_dispatch.x_sendfile_header+.
@@ -54,17 +56,17 @@ module ActionController #:nodoc:
       #
       # Read about the other Content-* HTTP headers if you'd like to
       # provide the user with more information (such as Content-Description) in
-      # http://www.w3.org/Protocols/rfc2616/rfc2616-sec14.html#sec14.11.
+      # https://www.w3.org/Protocols/rfc2616/rfc2616-sec14.html#sec14.11.
       #
       # Also be aware that the document may be cached by proxies and browsers.
       # The Pragma and Cache-Control headers declare how the file may be cached
       # by intermediaries. They default to require clients to validate with
       # the server before releasing cached responses. See
-      # http://www.mnot.net/cache_docs/ for an overview of web caching and
-      # http://www.w3.org/Protocols/rfc2616/rfc2616-sec14.html#sec14.9
+      # https://www.mnot.net/cache_docs/ for an overview of web caching and
+      # https://www.w3.org/Protocols/rfc2616/rfc2616-sec14.html#sec14.9
       # for the Cache-Control header spec.
       def send_file(path, options = {}) #:doc:
-        raise MissingFile, "Cannot read file #{path}" unless File.file?(path) and File.readable?(path)
+        raise MissingFile, "Cannot read file #{path}" unless File.file?(path) && File.readable?(path)
 
         options[:filename] ||= File.basename(path) unless options[:url_based_filename]
         send_file_headers! options
@@ -108,11 +110,13 @@ module ActionController #:nodoc:
         render options.slice(:status, :content_type).merge(body: data)
       end
 
-    private
       def send_file_headers!(options)
         type_provided = options.has_key?(:type)
 
         content_type = options.fetch(:type, DEFAULT_SEND_FILE_TYPE)
+        self.content_type = content_type
+        response.sending_file = true
+
         raise ArgumentError, ":type option required" if content_type.nil?
 
         if content_type.is_a?(Symbol)
@@ -122,7 +126,7 @@ module ActionController #:nodoc:
         else
           if !type_provided && options[:filename]
             # If type wasn't provided, try guessing from file extension.
-            content_type = Mime::Type.lookup_by_extension(File.extname(options[:filename]).downcase.delete('.')) || content_type
+            content_type = Mime::Type.lookup_by_extension(File.extname(options[:filename]).downcase.delete(".")) || content_type
           end
           self.content_type = content_type
         end
@@ -131,12 +135,10 @@ module ActionController #:nodoc:
         unless disposition.nil?
           disposition  = disposition.to_s
           disposition += %(; filename="#{options[:filename]}") if options[:filename]
-          headers['Content-Disposition'] = disposition
+          headers["Content-Disposition"] = disposition
         end
 
-        headers['Content-Transfer-Encoding'] = 'binary'
-
-        response.sending_file = true
+        headers["Content-Transfer-Encoding"] = "binary"
 
         # Fix a problem with IE 6.0 on opening downloaded files:
         # If Cache-Control: no-cache is set (which Rails does by default),
diff --git a/actionpack/lib/action_controller/metal/etag_with_flash.rb b/actionpack/lib/action_controller/metal/etag_with_flash.rb
new file mode 100644
index 0000000000..38899e2f16
--- /dev/null
+++ b/actionpack/lib/action_controller/metal/etag_with_flash.rb
@@ -0,0 +1,18 @@
+# frozen_string_literal: true
+
+module ActionController
+  # When you're using the flash, it's generally used as a conditional on the view.
+  # This means the content of the view depends on the flash. Which in turn means
+  # that the ETag for a response should be computed with the content of the flash
+  # in mind. This does that by including the content of the flash as a component
+  # in the ETag that's generated for a response.
+  module EtagWithFlash
+    extend ActiveSupport::Concern
+
+    include ActionController::ConditionalGet
+
+    included do
+      etag { flash unless flash.empty? }
+    end
+  end
+end
diff --git a/actionpack/lib/action_controller/metal/etag_with_template_digest.rb b/actionpack/lib/action_controller/metal/etag_with_template_digest.rb
index 669cf55bca..640c75536e 100644
--- a/actionpack/lib/action_controller/metal/etag_with_template_digest.rb
+++ b/actionpack/lib/action_controller/metal/etag_with_template_digest.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActionController
   # When our views change, they should bubble up into HTTP cache freshness
   # and bust browser caches. So the template digest for the current action
@@ -22,8 +24,7 @@ module ActionController
     include ActionController::ConditionalGet
 
     included do
-      class_attribute :etag_with_template_digest
-      self.etag_with_template_digest = true
+      class_attribute :etag_with_template_digest, default: true
 
       ActiveSupport.on_load :action_view, yield: true do
         etag do |options|
@@ -33,18 +34,24 @@ module ActionController
     end
 
     private
-    def determine_template_etag(options)
-      if template = pick_template_for_etag(options)
-        lookup_and_digest_template(template)
+      def determine_template_etag(options)
+        if template = pick_template_for_etag(options)
+          lookup_and_digest_template(template)
+        end
       end
-    end
 
-    def pick_template_for_etag(options)
-      options.fetch(:template) { "#{controller_name}/#{action_name}" }
-    end
+      # Pick the template digest to include in the ETag. If the +:template+ option
+      # is present, use the named template. If +:template+ is +nil+ or absent, use
+      # the default controller/action template. If +:template+ is false, omit the
+      # template digest from the ETag.
+      def pick_template_for_etag(options)
+        unless options[:template] == false
+          options[:template] || "#{controller_path}/#{action_name}"
+        end
+      end
 
-    def lookup_and_digest_template(template)
-      ActionView::Digestor.digest name: template, finder: lookup_context
-    end
+      def lookup_and_digest_template(template)
+        ActionView::Digestor.digest name: template, finder: lookup_context
+      end
   end
 end
diff --git a/actionpack/lib/action_controller/metal/exceptions.rb b/actionpack/lib/action_controller/metal/exceptions.rb
index 5c0ada37be..a65857d6ef 100644
--- a/actionpack/lib/action_controller/metal/exceptions.rb
+++ b/actionpack/lib/action_controller/metal/exceptions.rb
@@ -1,22 +1,14 @@
+# frozen_string_literal: true
+
 module ActionController
   class ActionControllerError < StandardError #:nodoc:
   end
 
   class BadRequest < ActionControllerError #:nodoc:
-    def initialize(msg = nil, e = nil)
-      if e
-        ActiveSupport::Deprecation.warn("Passing #original_exception is deprecated and has no effect. " \
-                                        "Exceptions will automatically capture the original exception.", caller)
-      end
-
+    def initialize(msg = nil)
       super(msg)
       set_backtrace $!.backtrace if $!
     end
-
-    def original_exception
-      ActiveSupport::Deprecation.warn("#original_exception is deprecated. Use #cause instead.", caller)
-      cause
-    end
   end
 
   class RenderError < ActionControllerError #:nodoc:
@@ -24,7 +16,7 @@ module ActionController
 
   class RoutingError < ActionControllerError #:nodoc:
     attr_reader :failures
-    def initialize(message, failures=[])
+    def initialize(message, failures = [])
       super(message)
       @failures = failures
     end
@@ -35,21 +27,18 @@ module ActionController
 
   class MethodNotAllowed < ActionControllerError #:nodoc:
     def initialize(*allowed_methods)
-      super("Only #{allowed_methods.to_sentence(:locale => :en)} requests are allowed.")
+      super("Only #{allowed_methods.to_sentence(locale: :en)} requests are allowed.")
     end
   end
 
   class NotImplemented < MethodNotAllowed #:nodoc:
   end
 
-  class UnknownController < ActionControllerError #:nodoc:
-  end
-
   class MissingFile < ActionControllerError #:nodoc:
   end
 
   class SessionOverflowError < ActionControllerError #:nodoc:
-    DEFAULT_MESSAGE = 'Your session data is larger than the data column in which it is to be stored. You must increase the size of your data column if you intend to store large data.'
+    DEFAULT_MESSAGE = "Your session data is larger than the data column in which it is to be stored. You must increase the size of your data column if you intend to store large data."
 
     def initialize(message = nil)
       super(message || DEFAULT_MESSAGE)
diff --git a/actionpack/lib/action_controller/metal/flash.rb b/actionpack/lib/action_controller/metal/flash.rb
index 65351284b9..5115c2fadf 100644
--- a/actionpack/lib/action_controller/metal/flash.rb
+++ b/actionpack/lib/action_controller/metal/flash.rb
@@ -1,10 +1,11 @@
+# frozen_string_literal: true
+
 module ActionController #:nodoc:
   module Flash
     extend ActiveSupport::Concern
 
     included do
-      class_attribute :_flash_types, instance_accessor: false
-      self._flash_types = []
+      class_attribute :_flash_types, instance_accessor: false, default: []
 
       delegate :flash, to: :request
       add_flash_types(:alert, :notice)
@@ -42,7 +43,7 @@ module ActionController #:nodoc:
       end
     end
 
-    protected
+    private
       def redirect_to(options = {}, response_status_and_flash = {}) #:doc:
         self.class._flash_types.each do |flash_type|
           if type = response_status_and_flash.delete(flash_type)
diff --git a/actionpack/lib/action_controller/metal/force_ssl.rb b/actionpack/lib/action_controller/metal/force_ssl.rb
index ea8e91ce24..0ba1f9f783 100644
--- a/actionpack/lib/action_controller/metal/force_ssl.rb
+++ b/actionpack/lib/action_controller/metal/force_ssl.rb
@@ -1,18 +1,20 @@
-require 'active_support/core_ext/hash/except'
-require 'active_support/core_ext/hash/slice'
+# frozen_string_literal: true
+
+require "active_support/core_ext/hash/except"
+require "active_support/core_ext/hash/slice"
 
 module ActionController
-  # This module provides a method which will redirect the browser to use HTTPS
-  # protocol. This will ensure that user's sensitive information will be
+  # This module provides a method which will redirect the browser to use the secured HTTPS
+  # protocol. This will ensure that users' sensitive information will be
   # transferred safely over the internet. You _should_ always force the browser
   # to use HTTPS when you're transferring sensitive information such as
   # user authentication, account information, or credit card information.
   #
   # Note that if you are really concerned about your application security,
   # you might consider using +config.force_ssl+ in your config file instead.
-  # That will ensure all the data transferred via HTTPS protocol and prevent
-  # the user from getting their session hijacked when accessing the site over
-  # unsecured HTTP protocol.
+  # That will ensure all the data is transferred via HTTPS, and will
+  # prevent the user from getting their session hijacked when accessing the
+  # site over unsecured HTTP protocol.
   module ForceSSL
     extend ActiveSupport::Concern
     include AbstractController::Callbacks
@@ -23,7 +25,7 @@ module ActionController
 
     module ClassMethods
       # Force the request to this particular controller or specified actions to be
-      # under HTTPS protocol.
+      # through the HTTPS protocol.
       #
       # If you need to disable this for any reason (e.g. development) then you can use
       # an +:if+ or +:unless+ condition.
@@ -71,15 +73,15 @@ module ActionController
     # Redirect the existing request to use the HTTPS protocol.
     #
     # ==== Parameters
-    # * <tt>host_or_options</tt> - Either a host name or any of the url &
+    # * <tt>host_or_options</tt> - Either a host name or any of the url and
     #   redirect options available to the <tt>force_ssl</tt> method.
     def force_ssl_redirect(host_or_options = nil)
       unless request.ssl?
         options = {
-          :protocol => 'https://',
-          :host     => request.host,
-          :path     => request.fullpath,
-          :status   => :moved_permanently
+          protocol: "https://",
+          host: request.host,
+          path: request.fullpath,
+          status: :moved_permanently
         }
 
         if host_or_options.is_a?(Hash)
@@ -89,7 +91,7 @@ module ActionController
         end
 
         secure_url = ActionDispatch::Http::URL.url_for(options.slice(*URL_OPTIONS))
-        flash.keep if respond_to?(:flash)
+        flash.keep if respond_to?(:flash) && request.respond_to?(:flash)
         redirect_to secure_url, options.slice(*REDIRECT_OPTIONS)
       end
     end
diff --git a/actionpack/lib/action_controller/metal/head.rb b/actionpack/lib/action_controller/metal/head.rb
index 5e9832fd4e..bac9bc5e5f 100644
--- a/actionpack/lib/action_controller/metal/head.rb
+++ b/actionpack/lib/action_controller/metal/head.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActionController
   module Head
     # Returns a response that has no content (merely headers). The options
@@ -18,13 +20,7 @@ module ActionController
     # See Rack::Utils::SYMBOL_TO_STATUS_CODE for a full list of valid +status+ symbols.
     def head(status, options = {})
       if status.is_a?(Hash)
-        msg = status[:status] ? 'The :status option' : 'The implicit :ok status'
-        options, status = status, status.delete(:status)
-
-        ActiveSupport::Deprecation.warn(<<-MSG.squish)
-          #{msg} on `head` has been deprecated and will be removed in Rails 5.1.
-          Please pass the status as a separate parameter before the options, instead.
-        MSG
+        raise ArgumentError, "#{status.inspect} is not a valid value for `status`."
       end
 
       status ||= :ok
@@ -33,7 +29,7 @@ module ActionController
       content_type = options.delete(:content_type)
 
       options.each do |key, value|
-        headers[key.to_s.dasherize.split('-').each { |v| v[0] = v[0].chr.upcase }.join('-')] = value.to_s
+        headers[key.to_s.dasherize.split("-").each { |v| v[0] = v[0].chr.upcase }.join("-")] = value.to_s
       end
 
       self.status = status
@@ -41,24 +37,24 @@ module ActionController
 
       self.response_body = ""
 
-      if include_content?(self.response_code)
+      if include_content?(response_code)
         self.content_type = content_type || (Mime[formats.first] if formats)
-        self.response.charset = false
+        response.charset = false
       end
 
       true
     end
 
     private
-    def include_content?(status)
-      case status
-      when 100..199
-        false
-      when 204, 205, 304
-        false
-      else
-        true
+      def include_content?(status)
+        case status
+        when 100..199
+          false
+        when 204, 205, 304
+          false
+        else
+          true
+        end
       end
-    end
   end
 end
diff --git a/actionpack/lib/action_controller/metal/helpers.rb b/actionpack/lib/action_controller/metal/helpers.rb
index 295f0cb66f..22c84e440b 100644
--- a/actionpack/lib/action_controller/metal/helpers.rb
+++ b/actionpack/lib/action_controller/metal/helpers.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActionController
   # The \Rails framework provides a large number of helpers for working with assets, dates, forms,
   # numbers and model objects, to name a few. These helpers are available to all templates
@@ -53,9 +55,8 @@ module ActionController
     include AbstractController::Helpers
 
     included do
-      class_attribute :helpers_path, :include_all_helpers
-      self.helpers_path ||= []
-      self.include_all_helpers = true
+      class_attribute :helpers_path, default: []
+      class_attribute :include_all_helpers, default: true
     end
 
     module ClassMethods
@@ -108,10 +109,10 @@ module ActionController
       end
 
       private
-      # Extract helper names from files in <tt>app/helpers/**/*_helper.rb</tt>
-      def all_application_helpers
-        all_helpers_from_path(helpers_path)
-      end
+        # Extract helper names from files in <tt>app/helpers/**/*_helper.rb</tt>
+        def all_application_helpers
+          all_helpers_from_path(helpers_path)
+        end
     end
 
     # Provides a proxy to access helper methods from outside the view.
diff --git a/actionpack/lib/action_controller/metal/http_authentication.rb b/actionpack/lib/action_controller/metal/http_authentication.rb
index 4639348509..01676f3237 100644
--- a/actionpack/lib/action_controller/metal/http_authentication.rb
+++ b/actionpack/lib/action_controller/metal/http_authentication.rb
@@ -1,5 +1,7 @@
-require 'base64'
-require 'active_support/security_utils'
+# frozen_string_literal: true
+
+require "base64"
+require "active_support/security_utils"
 
 module ActionController
   # Makes it dead easy to do HTTP Basic, Digest and Token authentication.
@@ -28,7 +30,7 @@ module ActionController
     #   class ApplicationController < ActionController::Base
     #     before_action :set_account, :authenticate
     #
-    #     protected
+    #     private
     #       def set_account
     #         @account = Account.find_by(url_name: request.subdomains.first)
     #       end
@@ -70,10 +72,10 @@ module ActionController
             before_action(options.except(:name, :password, :realm)) do
               authenticate_or_request_with_http_basic(options[:realm] || "Application") do |name, password|
                 # This comparison uses & so that it doesn't short circuit and
-                # uses `variable_size_secure_compare` so that length information
+                # uses `secure_compare` so that length information
                 # isn't leaked.
-                ActiveSupport::SecurityUtils.variable_size_secure_compare(name, options[:name]) &
-                  ActiveSupport::SecurityUtils.variable_size_secure_compare(password, options[:password])
+                ActiveSupport::SecurityUtils.secure_compare(name, options[:name]) &
+                  ActiveSupport::SecurityUtils.secure_compare(password, options[:password])
               end
             end
           end
@@ -99,23 +101,23 @@ module ActionController
       end
 
       def has_basic_credentials?(request)
-        request.authorization.present? && (auth_scheme(request).downcase == 'basic')
+        request.authorization.present? && (auth_scheme(request).downcase == "basic")
       end
 
       def user_name_and_password(request)
-        decode_credentials(request).split(':', 2)
+        decode_credentials(request).split(":", 2)
       end
 
       def decode_credentials(request)
-        ::Base64.decode64(auth_param(request) || '')
+        ::Base64.decode64(auth_param(request) || "")
       end
 
       def auth_scheme(request)
-        request.authorization.to_s.split(' ', 2).first
+        request.authorization.to_s.split(" ", 2).first
       end
 
       def auth_param(request)
-        request.authorization.to_s.split(' ', 2).second
+        request.authorization.to_s.split(" ", 2).second
       end
 
       def encode_credentials(user_name, password)
@@ -208,7 +210,7 @@ module ActionController
           password = password_procedure.call(credentials[:username])
           return false unless password
 
-          method = request.get_header('rack.methodoverride.original_method') || request.get_header('REQUEST_METHOD')
+          method = request.get_header("rack.methodoverride.original_method") || request.get_header("REQUEST_METHOD")
           uri    = credentials[:uri]
 
           [true, false].any? do |trailing_question_mark|
@@ -224,19 +226,19 @@ module ActionController
       # Returns the expected response for a request of +http_method+ to +uri+ with the decoded +credentials+ and the expected +password+
       # Optional parameter +password_is_ha1+ is set to +true+ by default, since best practice is to store ha1 digest instead
       # of a plain-text password.
-      def expected_response(http_method, uri, credentials, password, password_is_ha1=true)
+      def expected_response(http_method, uri, credentials, password, password_is_ha1 = true)
         ha1 = password_is_ha1 ? password : ha1(credentials, password)
-        ha2 = ::Digest::MD5.hexdigest([http_method.to_s.upcase, uri].join(':'))
-        ::Digest::MD5.hexdigest([ha1, credentials[:nonce], credentials[:nc], credentials[:cnonce], credentials[:qop], ha2].join(':'))
+        ha2 = ::Digest::MD5.hexdigest([http_method.to_s.upcase, uri].join(":"))
+        ::Digest::MD5.hexdigest([ha1, credentials[:nonce], credentials[:nc], credentials[:cnonce], credentials[:qop], ha2].join(":"))
       end
 
       def ha1(credentials, password)
-        ::Digest::MD5.hexdigest([credentials[:username], credentials[:realm], password].join(':'))
+        ::Digest::MD5.hexdigest([credentials[:username], credentials[:realm], password].join(":"))
       end
 
       def encode_credentials(http_method, credentials, password, password_is_ha1)
         credentials[:response] = expected_response(http_method, credentials[:uri], credentials, password, password_is_ha1)
-        "Digest " + credentials.sort_by {|x| x[0].to_s }.map {|v| "#{v[0]}='#{v[1]}'" }.join(', ')
+        "Digest " + credentials.sort_by { |x| x[0].to_s }.map { |v| "#{v[0]}='#{v[1]}'" }.join(", ")
       end
 
       def decode_credentials_header(request)
@@ -244,9 +246,9 @@ module ActionController
       end
 
       def decode_credentials(header)
-        ActiveSupport::HashWithIndifferentAccess[header.to_s.gsub(/^Digest\s+/, '').split(',').map do |pair|
-          key, value = pair.split('=', 2)
-          [key.strip, value.to_s.gsub(/^"|"$/,'').delete('\'')]
+        ActiveSupport::HashWithIndifferentAccess[header.to_s.gsub(/^Digest\s+/, "").split(",").map do |pair|
+          key, value = pair.split("=", 2)
+          [key.strip, value.to_s.gsub(/^"|"$/, "").delete("'")]
         end]
       end
 
@@ -314,7 +316,7 @@ module ActionController
       # Can be much shorter if the Stale directive is implemented. This would
       # allow a user to use new nonce without prompting the user again for their
       # username and password.
-      def validate_nonce(secret_key, request, value, seconds_to_timeout=5*60)
+      def validate_nonce(secret_key, request, value, seconds_to_timeout = 5 * 60)
         return false if value.nil?
         t = ::Base64.decode64(value).split(":").first.to_i
         nonce(secret_key, t) == value && (t - Time.now.to_i).abs <= seconds_to_timeout
@@ -324,7 +326,6 @@ module ActionController
       def opaque(secret_key)
         ::Digest::MD5.hexdigest(secret_key)
       end
-
     end
 
     # Makes it dead easy to do HTTP Token authentication.
@@ -349,10 +350,7 @@ module ActionController
     #         authenticate_or_request_with_http_token do |token, options|
     #           # Compare the tokens in a time-constant manner, to mitigate
     #           # timing attacks.
-    #           ActiveSupport::SecurityUtils.secure_compare(
-    #             ::Digest::SHA256.hexdigest(token),
-    #             ::Digest::SHA256.hexdigest(TOKEN)
-    #           )
+    #           ActiveSupport::SecurityUtils.secure_compare(token, TOKEN)
     #         end
     #       end
     #   end
@@ -364,7 +362,7 @@ module ActionController
     #   class ApplicationController < ActionController::Base
     #     before_action :set_account, :authenticate
     #
-    #     protected
+    #     private
     #       def set_account
     #         @account = Account.find_by(url_name: request.subdomains.first)
     #       end
@@ -406,7 +404,7 @@ module ActionController
     #
     #   RewriteRule ^(.*)$ dispatch.fcgi [E=X-HTTP_AUTHORIZATION:%{HTTP:Authorization},QSA,L]
     module Token
-      TOKEN_KEY = 'token='
+      TOKEN_KEY = "token="
       TOKEN_REGEX = /^(Token|Bearer)\s+/
       AUTHN_PAIR_DELIMITERS = /(?:,|;|\t+)/
       extend self
@@ -446,7 +444,7 @@ module ActionController
         end
       end
 
-      # Parses the token and options out of the token authorization header.
+      # Parses the token and options out of the token Authorization header.
       # The value for the Authorization header is expected to have the prefix
       # <tt>"Token"</tt> or <tt>"Bearer"</tt>. If the header looks like this:
       #   Authorization: Token token="abc", nonce="def"
@@ -476,14 +474,14 @@ module ActionController
 
       # This removes the <tt>"</tt> characters wrapping the value.
       def rewrite_param_values(array_params)
-        array_params.each { |param| (param[1] || "").gsub! %r/^"|"$/, '' }
+        array_params.each { |param| (param[1] || "".dup).gsub! %r/^"|"$/, "" }
       end
 
       # This method takes an authorization body and splits up the key-value
       # pairs by the standardized <tt>:</tt>, <tt>;</tt>, or <tt>\t</tt>
       # delimiters defined in +AUTHN_PAIR_DELIMITERS+.
       def raw_params(auth)
-        _raw_params = auth.sub(TOKEN_REGEX, '').split(/\s*#{AUTHN_PAIR_DELIMITERS}\s*/)
+        _raw_params = auth.sub(TOKEN_REGEX, "").split(/\s*#{AUTHN_PAIR_DELIMITERS}\s*/)
 
         if !(_raw_params.first =~ %r{\A#{TOKEN_KEY}})
           _raw_params[0] = "#{TOKEN_KEY}#{_raw_params.first}"
diff --git a/actionpack/lib/action_controller/metal/implicit_render.rb b/actionpack/lib/action_controller/metal/implicit_render.rb
index 6192fc0f9c..ac0c127cdc 100644
--- a/actionpack/lib/action_controller/metal/implicit_render.rb
+++ b/actionpack/lib/action_controller/metal/implicit_render.rb
@@ -1,14 +1,14 @@
-require 'active_support/core_ext/string/strip'
+# frozen_string_literal: true
 
 module ActionController
   # Handles implicit rendering for a controller action that does not
   # explicitly respond with +render+, +respond_to+, +redirect+, or +head+.
   #
-  # For API controllers, the implicit response is always 204 No Content.
+  # For API controllers, the implicit response is always <tt>204 No Content</tt>.
   #
   # For all other controllers, we use these heuristics to decide whether to
   # render a template, raise an error for a missing template, or respond with
-  # 204 No Content:
+  # <tt>204 No Content</tt>:
   #
   # First, if we DO find a template, it's rendered. Template lookup accounts
   # for the action name, locales, format, variant, template handlers, and more
@@ -25,9 +25,8 @@ module ActionController
   # <tt>ActionView::UnknownFormat</tt> with an explanation.
   #
   # Finally, if we DON'T find a template AND the request isn't a browser page
-  # load, then we implicitly respond with 204 No Content.
+  # load, then we implicitly respond with <tt>204 No Content</tt>.
   module ImplicitRender
-
     # :stopdoc:
     include BasicImplicitRender
 
@@ -49,7 +48,7 @@ module ActionController
           "NOTE! For XHR/Ajax or API requests, this action would normally " \
           "respond with 204 No Content: an empty white screen. Since you're " \
           "loading it in a web browser, we assume that you expected to " \
-          "actually render a template, not… nothing, so we're showing an " \
+          "actually render a template, not nothing, so we're showing an " \
           "error to be extra-clear. If you expect 204 No Content, carry on. " \
           "That's what you'll get from an XHR or API request. Give it a shot."
 
@@ -62,8 +61,8 @@ module ActionController
 
     def method_for_action(action_name)
       super || if template_exists?(action_name.to_s, _prefixes)
-        "default_render"
-      end
+                 "default_render"
+               end
     end
 
     private
diff --git a/actionpack/lib/action_controller/metal/instrumentation.rb b/actionpack/lib/action_controller/metal/instrumentation.rb
index 624a6d5b76..be9449629f 100644
--- a/actionpack/lib/action_controller/metal/instrumentation.rb
+++ b/actionpack/lib/action_controller/metal/instrumentation.rb
@@ -1,9 +1,11 @@
-require 'benchmark'
-require 'abstract_controller/logger'
+# frozen_string_literal: true
+
+require "benchmark"
+require "abstract_controller/logger"
 
 module ActionController
   # Adds instrumentation to several ends in ActionController::Base. It also provides
-  # some hooks related with process_action, this allows an ORM like Active Record
+  # some hooks related with process_action. This allows an ORM like Active Record
   # and/or DataMapper to plug in ActionController and show related information.
   #
   # Check ActiveRecord::Railties::ControllerRuntime for an example.
@@ -16,13 +18,13 @@ module ActionController
 
     def process_action(*args)
       raw_payload = {
-        :controller => self.class.name,
-        :action     => self.action_name,
-        :params     => request.filtered_parameters,
-        :headers    => request.headers,
-        :format     => request.format.ref,
-        :method     => request.request_method,
-        :path       => request.fullpath
+        controller: self.class.name,
+        action: action_name,
+        params: request.filtered_parameters,
+        headers: request.headers,
+        format: request.format.ref,
+        method: request.request_method,
+        path: request.fullpath
       }
 
       ActiveSupport::Notifications.instrument("start_processing.action_controller", raw_payload.dup)
@@ -46,9 +48,9 @@ module ActionController
       render_output
     end
 
-    def send_file(path, options={})
+    def send_file(path, options = {})
       ActiveSupport::Notifications.instrument("send_file.action_controller",
-        options.merge(:path => path)) do
+        options.merge(path: path)) do
         super
       end
     end
@@ -72,7 +74,7 @@ module ActionController
 
     # A hook invoked every time a before callback is halted.
     def halted_callback_hook(filter)
-      ActiveSupport::Notifications.instrument("halted_callback.action_controller", :filter => filter)
+      ActiveSupport::Notifications.instrument("halted_callback.action_controller", filter: filter)
     end
 
     # A hook which allows you to clean up any time, wrongly taken into account in
@@ -81,16 +83,13 @@ module ActionController
     #   def cleanup_view_runtime
     #     super - time_taken_in_something_expensive
     #   end
-    #
-    # :api: plugin
-    def cleanup_view_runtime #:nodoc:
+    def cleanup_view_runtime # :doc:
       yield
     end
 
     # Every time after an action is processed, this method is invoked
     # with the payload, so you can add more information.
-    # :api: plugin
-    def append_info_to_payload(payload) #:nodoc:
+    def append_info_to_payload(payload) # :doc:
       payload[:view_runtime] = view_runtime
     end
 
@@ -98,7 +97,6 @@ module ActionController
       # A hook which allows other frameworks to log what happened during
       # controller process action. This method should return an array
       # with the messages to be added.
-      # :api: plugin
       def log_process_action(payload) #:nodoc:
         messages, view_runtime = [], payload[:view_runtime]
         messages << ("Views: %.1fms" % view_runtime.to_f) if view_runtime
diff --git a/actionpack/lib/action_controller/metal/live.rb b/actionpack/lib/action_controller/metal/live.rb
index 5d395cd8bd..2f4c8fb83c 100644
--- a/actionpack/lib/action_controller/metal/live.rb
+++ b/actionpack/lib/action_controller/metal/live.rb
@@ -1,6 +1,8 @@
-require 'action_dispatch/http/response'
-require 'delegate'
-require 'active_support/json'
+# frozen_string_literal: true
+
+require "action_dispatch/http/response"
+require "delegate"
+require "active_support/json"
 
 module ActionController
   # Mix this module into your controller, and all actions in that controller
@@ -84,7 +86,6 @@ module ActionController
     # Note: SSEs are not currently supported by IE. However, they are supported
     # by Chrome, Firefox, Opera, and Safari.
     class SSE
-
       WHITELISTED_OPTIONS = %w( retry event id )
 
       def initialize(stream, options = {})
@@ -206,7 +207,12 @@ module ActionController
       private
 
         def each_chunk(&block)
-          while str = @buf.pop
+          loop do
+            str = nil
+            ActiveSupport::Dependencies.interlock.permit_concurrent_loads do
+              str = @buf.pop
+            end
+            break unless str
             yield str
           end
         end
@@ -215,18 +221,18 @@ module ActionController
     class Response < ActionDispatch::Response #:nodoc: all
       private
 
-      def before_committed
-        super
-        jar = request.cookie_jar
-        # The response can be committed multiple times
-        jar.write self unless committed?
-      end
+        def before_committed
+          super
+          jar = request.cookie_jar
+          # The response can be committed multiple times
+          jar.write self unless committed?
+        end
 
-      def build_buffer(response, body)
-        buf = Live::Buffer.new response
-        body.each { |part| buf.write part }
-        buf
-      end
+        def build_buffer(response, body)
+          buf = Live::Buffer.new response
+          body.each { |part| buf.write part }
+          buf
+        end
     end
 
     def process(name)
@@ -235,15 +241,15 @@ module ActionController
 
       error = nil
       # This processes the action in a child thread. It lets us return the
-      # response code and headers back up the rack stack, and still process
-      # the body in parallel with sending data to the client
+      # response code and headers back up the Rack stack, and still process
+      # the body in parallel with sending data to the client.
       new_controller_thread {
         ActiveSupport::Dependencies.interlock.running do
           t2 = Thread.current
 
           # Since we're processing the view in a different thread, copy the
           # thread locals from the main thread to the child thread. :'(
-          locals.each { |k,v| t2[k] = v }
+          locals.each { |k, v| t2[k] = v }
 
           begin
             super(name)
@@ -274,9 +280,9 @@ module ActionController
       raise error if error
     end
 
-    # Spawn a new thread to serve up the controller in.  This is to get
+    # Spawn a new thread to serve up the controller in. This is to get
     # around the fact that Rack isn't based around IOs and we need to use
-    # a thread to stream data from the response bodies.  Nobody should call
+    # a thread to stream data from the response bodies. Nobody should call
     # this method except in Rails internals. Seriously!
     def new_controller_thread # :nodoc:
       Thread.new {
@@ -291,7 +297,7 @@ module ActionController
       return unless logger
 
       logger.fatal do
-        message = "\n#{exception.class} (#{exception.message}):\n"
+        message = "\n#{exception.class} (#{exception.message}):\n".dup
         message << exception.annoted_source_code.to_s if exception.respond_to?(:annoted_source_code)
         message << "  " << exception.backtrace.join("\n  ")
         "#{message}\n\n"
diff --git a/actionpack/lib/action_controller/metal/mime_responds.rb b/actionpack/lib/action_controller/metal/mime_responds.rb
index 2e89af1a5e..2233b93406 100644
--- a/actionpack/lib/action_controller/metal/mime_responds.rb
+++ b/actionpack/lib/action_controller/metal/mime_responds.rb
@@ -1,4 +1,6 @@
-require 'abstract_controller/collector'
+# frozen_string_literal: true
+
+require "abstract_controller/collector"
 
 module ActionController #:nodoc:
   module MimeResponds
@@ -181,8 +183,8 @@ module ActionController #:nodoc:
     #
     #   request.variant = [:tablet, :phone]
     #
-    # which will work similarly to formats and MIME types negotiation. If there will be no
-    # +:tablet+ variant declared, +:phone+ variant will be picked:
+    # This will work similarly to formats and MIME types negotiation. If there
+    # is no +:tablet+ variant declared, the +:phone+ variant will be used:
     #
     #   respond_to do |format|
     #     format.html.none
@@ -280,8 +282,8 @@ module ActionController #:nodoc:
 
         def any(*args, &block)
           if block_given?
-            if args.any? && args.none?{ |a| a == @variant }
-              args.each{ |v| @variants[v] = block }
+            if args.any? && args.none? { |a| a == @variant }
+              args.each { |v| @variants[v] = block }
             else
               @variants[:any] = block
             end
diff --git a/actionpack/lib/action_controller/metal/parameter_encoding.rb b/actionpack/lib/action_controller/metal/parameter_encoding.rb
new file mode 100644
index 0000000000..7a45732d31
--- /dev/null
+++ b/actionpack/lib/action_controller/metal/parameter_encoding.rb
@@ -0,0 +1,51 @@
+# frozen_string_literal: true
+
+module ActionController
+  # Specify binary encoding for parameters for a given action.
+  module ParameterEncoding
+    extend ActiveSupport::Concern
+
+    module ClassMethods
+      def inherited(klass) # :nodoc:
+        super
+        klass.setup_param_encode
+      end
+
+      def setup_param_encode # :nodoc:
+        @_parameter_encodings = {}
+      end
+
+      def binary_params_for?(action) # :nodoc:
+        @_parameter_encodings[action.to_s]
+      end
+
+      # Specify that a given action's parameters should all be encoded as
+      # ASCII-8BIT (it "skips" the encoding default of UTF-8).
+      #
+      # For example, a controller would use it like this:
+      #
+      #   class RepositoryController < ActionController::Base
+      #     skip_parameter_encoding :show
+      #
+      #     def show
+      #       @repo = Repository.find_by_filesystem_path params[:file_path]
+      #
+      #       # `repo_name` is guaranteed to be UTF-8, but was ASCII-8BIT, so
+      #       # tag it as such
+      #       @repo_name = params[:repo_name].force_encoding 'UTF-8'
+      #     end
+      #
+      #     def index
+      #       @repositories = Repository.all
+      #     end
+      #   end
+      #
+      # The show action in the above controller would have all parameter values
+      # encoded as ASCII-8BIT. This is useful in the case where an application
+      # must handle data but encoding of the data is unknown, like file system data.
+      def skip_parameter_encoding(action)
+        @_parameter_encodings[action.to_s] = true
+      end
+    end
+  end
+end
diff --git a/actionpack/lib/action_controller/metal/params_wrapper.rb b/actionpack/lib/action_controller/metal/params_wrapper.rb
index c38fc40b81..a678377d4f 100644
--- a/actionpack/lib/action_controller/metal/params_wrapper.rb
+++ b/actionpack/lib/action_controller/metal/params_wrapper.rb
@@ -1,7 +1,9 @@
-require 'active_support/core_ext/hash/slice'
-require 'active_support/core_ext/hash/except'
-require 'active_support/core_ext/module/anonymous'
-require 'action_dispatch/http/mime_type'
+# frozen_string_literal: true
+
+require "active_support/core_ext/hash/slice"
+require "active_support/core_ext/hash/except"
+require "active_support/core_ext/module/anonymous"
+require "action_dispatch/http/mime_type"
 
 module ActionController
   # Wraps the parameters hash into a nested hash. This will allow clients to
@@ -71,7 +73,7 @@ module ActionController
 
     EXCLUDE_PARAMETERS = %w(authenticity_token _method utf8)
 
-    require 'mutex_m'
+    require "mutex_m"
 
     class Options < Struct.new(:name, :format, :include, :exclude, :klass, :model) # :nodoc:
       include Mutex_m
@@ -105,7 +107,19 @@ module ActionController
 
           unless super || exclude
             if m.respond_to?(:attribute_names) && m.attribute_names.any?
-              self.include = m.attribute_names
+              if m.respond_to?(:stored_attributes) && !m.stored_attributes.empty?
+                self.include = m.attribute_names + m.stored_attributes.values.flatten.map(&:to_s)
+              else
+                self.include = m.attribute_names
+              end
+
+              if m.respond_to?(:nested_attributes_options) && m.nested_attributes_options.keys.any?
+                self.include += m.nested_attributes_options.keys.map do |key|
+                  key.to_s.concat("_attributes")
+                end
+              end
+
+              self.include
             end
           end
         end
@@ -128,35 +142,34 @@ module ActionController
       end
 
       private
-      # Determine the wrapper model from the controller's name. By convention,
-      # this could be done by trying to find the defined model that has the
-      # same singular name as the controller. For example, +UsersController+
-      # will try to find if the +User+ model exists.
-      #
-      # This method also does namespace lookup. Foo::Bar::UsersController will
-      # try to find Foo::Bar::User, Foo::User and finally User.
-      def _default_wrap_model #:nodoc:
-        return nil if klass.anonymous?
-        model_name = klass.name.sub(/Controller$/, '').classify
-
-        begin
-          if model_klass = model_name.safe_constantize
-            model_klass
-          else
-            namespaces = model_name.split("::")
-            namespaces.delete_at(-2)
-            break if namespaces.last == model_name
-            model_name = namespaces.join("::")
-          end
-        end until model_klass
+        # Determine the wrapper model from the controller's name. By convention,
+        # this could be done by trying to find the defined model that has the
+        # same singular name as the controller. For example, +UsersController+
+        # will try to find if the +User+ model exists.
+        #
+        # This method also does namespace lookup. Foo::Bar::UsersController will
+        # try to find Foo::Bar::User, Foo::User and finally User.
+        def _default_wrap_model
+          return nil if klass.anonymous?
+          model_name = klass.name.sub(/Controller$/, "").classify
+
+          begin
+            if model_klass = model_name.safe_constantize
+              model_klass
+            else
+              namespaces = model_name.split("::")
+              namespaces.delete_at(-2)
+              break if namespaces.last == model_name
+              model_name = namespaces.join("::")
+            end
+          end until model_klass
 
-        model_klass
-      end
+          model_klass
+        end
     end
 
     included do
-      class_attribute :_wrapper_options
-      self._wrapper_options = Options.from_hash(format: [])
+      class_attribute :_wrapper_options, default: Options.from_hash(format: [])
     end
 
     module ClassMethods
@@ -198,14 +211,14 @@ module ActionController
         when Hash
           options = name_or_model_or_options
         when false
-          options = options.merge(:format => [])
+          options = options.merge(format: [])
         when Symbol, String
-          options = options.merge(:name => name_or_model_or_options)
+          options = options.merge(name: name_or_model_or_options)
         else
           model = name_or_model_or_options
         end
 
-        opts   = Options.from_hash _wrapper_options.to_h.slice(:format).merge(options)
+        opts = Options.from_hash _wrapper_options.to_h.slice(:format).merge(options)
         opts.model = model
         opts.klass = self
 
@@ -213,7 +226,7 @@ module ActionController
       end
 
       # Sets the default wrapper key or model which will be used to determine
-      # wrapper key and attribute names. Will be called automatically when the
+      # wrapper key and attribute names. Called automatically when the
       # module is inherited.
       def inherited(klass)
         if klass._wrapper_options.format.any?
@@ -225,24 +238,19 @@ module ActionController
       end
     end
 
-    # Performs parameters wrapping upon the request. Will be called automatically
+    # Performs parameters wrapping upon the request. Called automatically
     # by the metal call stack.
     def process_action(*args)
       if _wrapper_enabled?
-        if request.parameters[_wrapper_key].present?
-          wrapped_hash = _extract_parameters(request.parameters)
-        else
-          wrapped_hash = _wrap_parameters request.request_parameters
-        end
-
+        wrapped_hash = _wrap_parameters request.request_parameters
         wrapped_keys = request.request_parameters.keys
         wrapped_filtered_hash = _wrap_parameters request.filtered_parameters.slice(*wrapped_keys)
 
-        # This will make the wrapped hash accessible from controller and view
+        # This will make the wrapped hash accessible from controller and view.
         request.parameters.merge! wrapped_hash
         request.request_parameters.merge! wrapped_hash
 
-        # This will display the wrapped hash in the log file
+        # This will display the wrapped hash in the log file.
         request.filtered_parameters.merge! wrapped_filtered_hash
       end
       super
@@ -279,7 +287,7 @@ module ActionController
         return false unless request.has_content_type?
 
         ref = request.content_mime_type.ref
-        _wrapper_formats.include?(ref) && _wrapper_key && !request.request_parameters[_wrapper_key]
+        _wrapper_formats.include?(ref) && _wrapper_key && !request.parameters.key?(_wrapper_key)
       end
   end
 end
diff --git a/actionpack/lib/action_controller/metal/redirecting.rb b/actionpack/lib/action_controller/metal/redirecting.rb
index 3c7cc15627..4c2b5120eb 100644
--- a/actionpack/lib/action_controller/metal/redirecting.rb
+++ b/actionpack/lib/action_controller/metal/redirecting.rb
@@ -1,12 +1,6 @@
-module ActionController
-  class RedirectBackError < AbstractController::Error #:nodoc:
-    DEFAULT_MESSAGE = 'No HTTP_REFERER was set in the request to this action, so redirect_to :back could not be called successfully. If this is a test, make sure to specify request.env["HTTP_REFERER"].'
-
-    def initialize(message = nil)
-      super(message || DEFAULT_MESSAGE)
-    end
-  end
+# frozen_string_literal: true
 
+module ActionController
   module Redirecting
     extend ActiveSupport::Concern
 
@@ -24,27 +18,27 @@ module ActionController
     # === Examples:
     #
     #   redirect_to action: "show", id: 5
-    #   redirect_to post
+    #   redirect_to @post
     #   redirect_to "http://www.rubyonrails.org"
     #   redirect_to "/images/screenshot.jpg"
-    #   redirect_to articles_url
+    #   redirect_to posts_url
     #   redirect_to proc { edit_post_url(@post) }
     #
-    # The redirection happens as a "302 Found" header unless otherwise specified using the <tt>:status</tt> option:
+    # The redirection happens as a <tt>302 Found</tt> header unless otherwise specified using the <tt>:status</tt> option:
     #
     #   redirect_to post_url(@post), status: :found
     #   redirect_to action: 'atom', status: :moved_permanently
     #   redirect_to post_url(@post), status: 301
     #   redirect_to action: 'atom', status: 302
     #
-    # The status code can either be a standard {HTTP Status code}[http://www.iana.org/assignments/http-status-codes] as an
+    # The status code can either be a standard {HTTP Status code}[https://www.iana.org/assignments/http-status-codes] as an
     # integer, or a symbol representing the downcased, underscored and symbolized description.
     # Note that the status code must be a 3xx HTTP code, or redirection will not occur.
     #
     # If you are using XHR requests other than GET or POST and redirecting after the
     # request then some browsers will follow the redirect using the original request
     # method. This may lead to undesirable behavior such as a double DELETE. To work
-    # around this  you can return a <tt>303 See Other</tt> status code which will be
+    # around this you can return a <tt>303 See Other</tt> status code which will be
     # followed using a GET request.
     #
     #   redirect_to posts_url, status: :see_other
@@ -58,39 +52,45 @@ module ActionController
     #   redirect_to post_url(@post), status: 301, flash: { updated_post_id: @post.id }
     #   redirect_to({ action: 'atom' }, alert: "Something serious happened")
     #
-    def redirect_to(options = {}, response_status = {}) #:doc:
+    # Statements after +redirect_to+ in our controller get executed, so +redirect_to+ doesn't stop the execution of the function.
+    # To terminate the execution of the function immediately after the +redirect_to+, use return.
+    #   redirect_to post_url(@post) and return
+    def redirect_to(options = {}, response_status = {})
       raise ActionControllerError.new("Cannot redirect to nil!") unless options
       raise AbstractController::DoubleRenderError if response_body
 
       self.status        = _extract_redirect_to_status(options, response_status)
       self.location      = _compute_redirect_to_location(request, options)
-      self.response_body = "<html><body>You are being <a href=\"#{ERB::Util.unwrapped_html_escape(location)}\">redirected</a>.</body></html>"
+      self.response_body = "<html><body>You are being <a href=\"#{ERB::Util.unwrapped_html_escape(response.location)}\">redirected</a>.</body></html>"
     end
 
     # Redirects the browser to the page that issued the request (the referrer)
     # if possible, otherwise redirects to the provided default fallback
     # location.
     #
-    # The referrer information is pulled from the HTTP `Referer` (sic) header on
+    # The referrer information is pulled from the HTTP +Referer+ (sic) header on
     # the request. This is an optional header and its presence on the request is
     # subject to browser security settings and user preferences. If the request
     # is missing this header, the <tt>fallback_location</tt> will be used.
     #
     #   redirect_back fallback_location: { action: "show", id: 5 }
-    #   redirect_back fallback_location: post
+    #   redirect_back fallback_location: @post
     #   redirect_back fallback_location: "http://www.rubyonrails.org"
-    #   redirect_back fallback_location:  "/images/screenshot.jpg"
-    #   redirect_back fallback_location:  articles_url
-    #   redirect_back fallback_location:  proc { edit_post_url(@post) }
+    #   redirect_back fallback_location: "/images/screenshot.jpg"
+    #   redirect_back fallback_location: posts_url
+    #   redirect_back fallback_location: proc { edit_post_url(@post) }
+    #   redirect_back fallback_location: '/', allow_other_host: false
     #
-    # All options that can be passed to <tt>redirect_to</tt> are accepted as
+    # ==== Options
+    # * <tt>:fallback_location</tt> - The default fallback location that will be used on missing +Referer+ header.
+    # * <tt>:allow_other_host</tt> - Allow or disallow redirection to the host that is different to the current host, defaults to true.
+    #
+    # All other options that can be passed to <tt>redirect_to</tt> are accepted as
     # options and the behavior is identical.
-    def redirect_back(fallback_location:, **args)
-      if referer = request.headers["Referer"]
-        redirect_to referer, **args
-      else
-        redirect_to fallback_location, **args
-      end
+    def redirect_back(fallback_location:, allow_other_host: true, **args)
+      referer = request.headers["Referer"]
+      redirect_to_referer = referer && (allow_other_host || _url_host_allowed?(referer))
+      redirect_to redirect_to_referer ? referer : fallback_location, **args
     end
 
     def _compute_redirect_to_location(request, options) #:nodoc:
@@ -98,20 +98,12 @@ module ActionController
       # The scheme name consist of a letter followed by any combination of
       # letters, digits, and the plus ("+"), period ("."), or hyphen ("-")
       # characters; and is terminated by a colon (":").
-      # See http://tools.ietf.org/html/rfc3986#section-3.1
+      # See https://tools.ietf.org/html/rfc3986#section-3.1
       # The protocol relative scheme starts with a double slash "//".
       when /\A([a-z][a-z\d\-+\.]*:|\/\/).*/i
         options
       when String
         request.protocol + request.host_with_port + options
-      when :back
-        ActiveSupport::Deprecation.warn(<<-MESSAGE.squish)
-          `redirect_to :back` is deprecated and will be removed from Rails 5.1.
-          Please use `redirect_back(fallback_location: fallback_location)` where
-          `fallback_location` represents the location to use if the request has
-          no HTTP referer information.
-        MESSAGE
-        request.headers["Referer"] or raise RedirectBackError
       when Proc
         _compute_redirect_to_location request, options.call
       else
@@ -131,5 +123,11 @@ module ActionController
           302
         end
       end
+
+      def _url_host_allowed?(url)
+        URI(url.to_s).host == request.host
+      rescue ArgumentError, URI::Error
+        false
+      end
   end
 end
diff --git a/actionpack/lib/action_controller/metal/renderers.rb b/actionpack/lib/action_controller/metal/renderers.rb
index 1735609cd9..b81d3ef539 100644
--- a/actionpack/lib/action_controller/metal/renderers.rb
+++ b/actionpack/lib/action_controller/metal/renderers.rb
@@ -1,4 +1,6 @@
-require 'set'
+# frozen_string_literal: true
+
+require "set"
 
 module ActionController
   # See <tt>Renderers.add</tt>
@@ -26,8 +28,7 @@ module ActionController
     RENDERERS = Set.new
 
     included do
-      class_attribute :_renderers
-      self._renderers = Set.new.freeze
+      class_attribute :_renderers, default: Set.new.freeze
     end
 
     # Used in <tt>ActionController::Base</tt>
@@ -71,8 +72,6 @@ module ActionController
     #       format.csv { render csv: @csvable, filename: @csvable.name }
     #     end
     #   end
-    # To use renderers and their mime types in more concise ways, see
-    # <tt>ActionController::MimeResponds::ClassMethods.respond_to</tt>
     def self.add(key, &block)
       define_method(_render_with_renderer_method_name(key), &block)
       RENDERERS << key.to_sym
@@ -86,7 +85,7 @@ module ActionController
     def self.remove(key)
       RENDERERS.delete(key.to_sym)
       method_name = _render_with_renderer_method_name(key)
-      remove_method(method_name) if method_defined?(method_name)
+      remove_possible_method(method_name)
     end
 
     def self._render_with_renderer_method_name(key)
@@ -94,7 +93,6 @@ module ActionController
     end
 
     module ClassMethods
-
       # Adds, by name, a renderer or renderers to the +_renderers+ available
       # to call within controller actions.
       #
@@ -107,7 +105,7 @@ module ActionController
       #
       # Since <tt>ActionController::Metal</tt> controllers cannot render, the controller
       # must include <tt>AbstractController::Rendering</tt>, <tt>ActionController::Rendering</tt>,
-      # and <tt>ActionController::Renderers</tt>, and have at lest one renderer.
+      # and <tt>ActionController::Renderers</tt>, and have at least one renderer.
       #
       # Rather than including <tt>ActionController::Renderers::All</tt> and including all renderers,
       # you may specify which renderers to include by passing the renderer name or names to
diff --git a/actionpack/lib/action_controller/metal/rendering.rb b/actionpack/lib/action_controller/metal/rendering.rb
index cce6fe7787..6d181e6456 100644
--- a/actionpack/lib/action_controller/metal/rendering.rb
+++ b/actionpack/lib/action_controller/metal/rendering.rb
@@ -1,10 +1,10 @@
-require 'active_support/core_ext/string/filters'
+# frozen_string_literal: true
 
 module ActionController
   module Rendering
     extend ActiveSupport::Concern
 
-    RENDER_FORMATS_IN_PRIORITY = [:body, :text, :plain, :html]
+    RENDER_FORMATS_IN_PRIORITY = [:body, :plain, :html]
 
     module ClassMethods
       # Documentation at ActionController::Renderer#render
@@ -32,15 +32,15 @@ module ActionController
 
     # Check for double render errors and set the content_type after rendering.
     def render(*args) #:nodoc:
-      raise ::AbstractController::DoubleRenderError if self.response_body
+      raise ::AbstractController::DoubleRenderError if response_body
       super
     end
 
-    # Overwrite render_to_string because body can now be set to a rack body.
+    # Overwrite render_to_string because body can now be set to a Rack body.
     def render_to_string(*)
       result = super
       if result.respond_to?(:each)
-        string = ""
+        string = "".dup
         result.each { |r| string << r }
         string
       else
@@ -49,84 +49,74 @@ module ActionController
     end
 
     def render_to_body(options = {})
-      super || _render_in_priorities(options) || ' '
+      super || _render_in_priorities(options) || " "
     end
 
     private
 
-    def _render_in_priorities(options)
-      RENDER_FORMATS_IN_PRIORITY.each do |format|
-        return options[format] if options.key?(format)
+      def _process_variant(options)
+        if defined?(request) && !request.nil? && request.variant.present?
+          options[:variant] = request.variant
+        end
       end
 
-      nil
-    end
-
-    def _set_html_content_type
-      self.content_type = Mime[:html].to_s
-    end
+      def _render_in_priorities(options)
+        RENDER_FORMATS_IN_PRIORITY.each do |format|
+          return options[format] if options.key?(format)
+        end
 
-    def _set_rendered_content_type(format)
-      unless response.content_type
-        self.content_type = format.to_s
+        nil
       end
-    end
 
-    # Normalize arguments by catching blocks and setting them on :update.
-    def _normalize_args(action=nil, options={}, &blk) #:nodoc:
-      options = super
-      options[:update] = blk if block_given?
-      options
-    end
-
-    # Normalize both text and status options.
-    def _normalize_options(options) #:nodoc:
-      _normalize_text(options)
-
-      if options[:text]
-        ActiveSupport::Deprecation.warn <<-WARNING.squish
-          `render :text` is deprecated because it does not actually render a
-          `text/plain` response. Switch to `render plain: 'plain text'` to
-          render as `text/plain`, `render html: '<strong>HTML</strong>'` to
-          render as `text/html`, or `render body: 'raw'` to match the deprecated
-          behavior and render with the default Content-Type, which is
-          `text/plain`.
-        WARNING
+      def _set_html_content_type
+        self.content_type = Mime[:html].to_s
       end
 
-      if options[:html]
-        options[:html] = ERB::Util.html_escape(options[:html])
+      def _set_rendered_content_type(format)
+        if format && !response.content_type
+          self.content_type = format.to_s
+        end
       end
 
-      if options.delete(:nothing)
-        ActiveSupport::Deprecation.warn("`:nothing` option is deprecated and will be removed in Rails 5.1. Use `head` method to respond with empty response body.")
-        options[:body] = nil
+      # Normalize arguments by catching blocks and setting them on :update.
+      def _normalize_args(action = nil, options = {}, &blk)
+        options = super
+        options[:update] = blk if block_given?
+        options
       end
 
-      if options[:status]
-        options[:status] = Rack::Utils.status_code(options[:status])
-      end
+      # Normalize both text and status options.
+      def _normalize_options(options)
+        _normalize_text(options)
 
-      super
-    end
+        if options[:html]
+          options[:html] = ERB::Util.html_escape(options[:html])
+        end
 
-    def _normalize_text(options)
-      RENDER_FORMATS_IN_PRIORITY.each do |format|
-        if options.key?(format) && options[format].respond_to?(:to_text)
-          options[format] = options[format].to_text
+        if options[:status]
+          options[:status] = Rack::Utils.status_code(options[:status])
         end
+
+        super
       end
-    end
 
-    # Process controller specific options, as status, content-type and location.
-    def _process_options(options) #:nodoc:
-      status, content_type, location = options.values_at(:status, :content_type, :location)
+      def _normalize_text(options)
+        RENDER_FORMATS_IN_PRIORITY.each do |format|
+          if options.key?(format) && options[format].respond_to?(:to_text)
+            options[format] = options[format].to_text
+          end
+        end
+      end
 
-      self.status = status if status
-      self.content_type = content_type if content_type
-      self.headers["Location"] = url_for(location) if location
+      # Process controller specific options, as status, content-type and location.
+      def _process_options(options)
+        status, content_type, location = options.values_at(:status, :content_type, :location)
 
-      super
-    end
+        self.status = status if status
+        self.content_type = content_type if content_type
+        headers["Location"] = url_for(location) if location
+
+        super
+      end
   end
 end
diff --git a/actionpack/lib/action_controller/metal/request_forgery_protection.rb b/actionpack/lib/action_controller/metal/request_forgery_protection.rb
index 0559fbc6ce..767eddb361 100644
--- a/actionpack/lib/action_controller/metal/request_forgery_protection.rb
+++ b/actionpack/lib/action_controller/metal/request_forgery_protection.rb
@@ -1,6 +1,8 @@
-require 'rack/session/abstract/id'
-require 'action_controller/metal/exceptions'
-require 'active_support/security_utils'
+# frozen_string_literal: true
+
+require "rack/session/abstract/id"
+require "action_controller/metal/exceptions"
+require "active_support/security_utils"
 
 module ActionController #:nodoc:
   class InvalidAuthenticityToken < ActionControllerError #:nodoc:
@@ -20,7 +22,7 @@ module ActionController #:nodoc:
   # Since HTML and JavaScript requests are typically made from the browser, we
   # need to ensure to verify request authenticity for the web browser. We can
   # use session-oriented authentication for these types of requests, by using
-  # the `protect_from_forgery` method in our controllers.
+  # the <tt>protect_from_forgery</tt> method in our controllers.
   #
   # GET requests are not protected since they don't have side effects like writing
   # to the database and don't leak sensitive information. JavaScript requests are
@@ -85,6 +87,10 @@ module ActionController #:nodoc:
       config_accessor :per_form_csrf_tokens
       self.per_form_csrf_tokens = false
 
+      # Controls whether forgery protection is enabled by default.
+      config_accessor :default_protect_from_forgery
+      self.default_protect_from_forgery = false
+
       helper_method :form_authenticity_token
       helper_method :protect_against_forgery?
     end
@@ -109,10 +115,10 @@ module ActionController #:nodoc:
       # * <tt>:only/:except</tt> - Only apply forgery protection to a subset of actions. For example <tt>only: [ :create, :create_all ]</tt>.
       # * <tt>:if/:unless</tt> - Turn off the forgery protection entirely depending on the passed Proc or method reference.
       # * <tt>:prepend</tt> - By default, the verification of the authentication token will be added at the position of the
-      #    protect_from_forgery call in your application. This means any callbacks added before are run first. This is useful
-      #    when you want your forgery protection to depend on other callbacks, like authentication methods (Oauth vs Cookie auth).
+      #   protect_from_forgery call in your application. This means any callbacks added before are run first. This is useful
+      #   when you want your forgery protection to depend on other callbacks, like authentication methods (Oauth vs Cookie auth).
       #
-      #    If you need to add verification to the beginning of the callback chain, use <tt>prepend: true</tt>.
+      #   If you need to add verification to the beginning of the callback chain, use <tt>prepend: true</tt>.
       # * <tt>:with</tt> - Set the method to handle unverified request.
       #
       # Valid unverified request handling methods are:
@@ -128,13 +134,22 @@ module ActionController #:nodoc:
         append_after_action :verify_same_origin_request
       end
 
+      # Turn off request forgery protection. This is a wrapper for:
+      #
+      #   skip_before_action :verify_authenticity_token
+      #
+      # See +skip_before_action+ for allowed options.
+      def skip_forgery_protection(options = {})
+        skip_before_action :verify_authenticity_token, options
+      end
+
       private
 
-      def protection_method_class(name)
-        ActionController::RequestForgeryProtection::ProtectionMethods.const_get(name.to_s.classify)
-      rescue NameError
-        raise ArgumentError, 'Invalid request forgery protection method, use :null_session, :exception, or :reset_session'
-      end
+        def protection_method_class(name)
+          ActionController::RequestForgeryProtection::ProtectionMethods.const_get(name.to_s.classify)
+        rescue NameError
+          raise ArgumentError, "Invalid request forgery protection method, use :null_session, :exception, or :reset_session"
+        end
     end
 
     module ProtectionMethods
@@ -152,28 +167,28 @@ module ActionController #:nodoc:
           request.cookie_jar = NullCookieJar.build(request, {})
         end
 
-        protected
+        private
 
-        class NullSessionHash < Rack::Session::Abstract::SessionHash #:nodoc:
-          def initialize(req)
-            super(nil, req)
-            @data = {}
-            @loaded = true
-          end
+          class NullSessionHash < Rack::Session::Abstract::SessionHash #:nodoc:
+            def initialize(req)
+              super(nil, req)
+              @data = {}
+              @loaded = true
+            end
 
-          # no-op
-          def destroy; end
+            # no-op
+            def destroy; end
 
-          def exists?
-            true
+            def exists?
+              true
+            end
           end
-        end
 
-        class NullCookieJar < ActionDispatch::Cookies::CookieJar #:nodoc:
-          def write(*)
-            # nothing
+          class NullCookieJar < ActionDispatch::Cookies::CookieJar #:nodoc:
+            def write(*)
+              # nothing
+            end
           end
-        end
       end
 
       class ResetSession
@@ -197,29 +212,33 @@ module ActionController #:nodoc:
       end
     end
 
-    protected
+    private
       # The actual before_action that is used to verify the CSRF token.
       # Don't override this directly. Provide your own forgery protection
       # strategy instead. If you override, you'll disable same-origin
-      # `<script>` verification.
+      # <tt><script></tt> verification.
       #
       # Lean on the protect_from_forgery declaration to mark which actions are
       # due for same-origin request verification. If protect_from_forgery is
       # enabled on an action, this before_action flags its after_action to
       # verify that JavaScript responses are for XHR requests, ensuring they
       # follow the browser's same-origin policy.
-      def verify_authenticity_token
+      def verify_authenticity_token # :doc:
         mark_for_same_origin_verification!
 
         if !verified_request?
           if logger && log_warning_on_csrf_failure
-            logger.warn "Can't verify CSRF token authenticity."
+            if valid_request_origin?
+              logger.warn "Can't verify CSRF token authenticity."
+            else
+              logger.warn "HTTP Origin header (#{request.origin}) didn't match request.base_url (#{request.base_url})"
+            end
           end
           handle_unverified_request
         end
       end
 
-      def handle_unverified_request
+      def handle_unverified_request # :doc:
         forgery_protection_strategy.new(self).handle_unverified_request
       end
 
@@ -229,11 +248,12 @@ module ActionController #:nodoc:
         "If you know what you're doing, go ahead and disable forgery " \
         "protection on this action to permit cross-origin JavaScript embedding."
       private_constant :CROSS_ORIGIN_JAVASCRIPT_WARNING
+      # :startdoc:
 
-      # If `verify_authenticity_token` was run (indicating that we have
+      # If +verify_authenticity_token+ was run (indicating that we have
       # forgery protection enabled for this request) then also verify that
       # we aren't serving an unauthorized cross-origin response.
-      def verify_same_origin_request
+      def verify_same_origin_request # :doc:
         if marked_for_same_origin_verification? && non_xhr_javascript_response?
           if logger && log_warning_on_csrf_failure
             logger.warn CROSS_ORIGIN_JAVASCRIPT_WARNING
@@ -243,18 +263,18 @@ module ActionController #:nodoc:
       end
 
       # GET requests are checked for cross-origin JavaScript after rendering.
-      def mark_for_same_origin_verification!
+      def mark_for_same_origin_verification! # :doc:
         @marked_for_same_origin_verification = request.get?
       end
 
-      # If the `verify_authenticity_token` before_action ran, verify that
+      # If the +verify_authenticity_token+ before_action ran, verify that
       # JavaScript responses are only served to same-origin GET requests.
-      def marked_for_same_origin_verification?
+      def marked_for_same_origin_verification? # :doc:
         @marked_for_same_origin_verification ||= false
       end
 
       # Check for cross-origin JavaScript responses.
-      def non_xhr_javascript_response?
+      def non_xhr_javascript_response? # :doc:
         content_type =~ %r(\Atext/javascript) && !request.xhr?
       end
 
@@ -262,23 +282,23 @@ module ActionController #:nodoc:
 
       # Returns true or false if a request is verified. Checks:
       #
-      # * Is it a GET or HEAD request?  Gets should be safe and idempotent
+      # * Is it a GET or HEAD request? GETs should be safe and idempotent
       # * Does the form_authenticity_token match the given token value from the params?
-      # * Does the X-CSRF-Token header match the form_authenticity_token
-      def verified_request?
+      # * Does the X-CSRF-Token header match the form_authenticity_token?
+      def verified_request? # :doc:
         !protect_against_forgery? || request.get? || request.head? ||
           (valid_request_origin? && any_authenticity_token_valid?)
       end
 
       # Checks if any of the authenticity tokens from the request are valid.
-      def any_authenticity_token_valid?
+      def any_authenticity_token_valid? # :doc:
         request_authenticity_tokens.any? do |token|
           valid_authenticity_token?(session, token)
         end
       end
 
       # Possible authenticity tokens sent in the request.
-      def request_authenticity_tokens
+      def request_authenticity_tokens # :doc:
         [form_authenticity_param, request.x_csrf_token]
       end
 
@@ -290,7 +310,7 @@ module ActionController #:nodoc:
       # Creates a masked version of the authenticity token that varies
       # on each request. The masking is used to mitigate SSL attacks
       # like BREACH.
-      def masked_authenticity_token(session, form_options: {})
+      def masked_authenticity_token(session, form_options: {}) # :doc:
         action, method = form_options.values_at(:action, :method)
 
         raw_token = if per_form_csrf_tokens && action && method
@@ -309,7 +329,7 @@ module ActionController #:nodoc:
       # Checks the client's masked token to see if it matches the
       # session token. Essentially the inverse of
       # +masked_authenticity_token+.
-      def valid_authenticity_token?(session, encoded_masked_token)
+      def valid_authenticity_token?(session, encoded_masked_token) # :doc:
         if encoded_masked_token.nil? || encoded_masked_token.empty? || !encoded_masked_token.is_a?(String)
           return false
         end
@@ -327,7 +347,7 @@ module ActionController #:nodoc:
         if masked_token.length == AUTHENTICITY_TOKEN_LENGTH
           # This is actually an unmasked token. This is expected if
           # you have just upgraded to masked tokens, but should stop
-          # happening shortly after installing this gem
+          # happening shortly after installing this gem.
           compare_with_real_token masked_token, session
 
         elsif masked_token.length == AUTHENTICITY_TOKEN_LENGTH * 2
@@ -336,23 +356,23 @@ module ActionController #:nodoc:
           compare_with_real_token(csrf_token, session) ||
             valid_per_form_csrf_token?(csrf_token, session)
         else
-          false # Token is malformed
+          false # Token is malformed.
         end
       end
 
-      def unmask_token(masked_token)
+      def unmask_token(masked_token) # :doc:
         # Split the token into the one-time pad and the encrypted
-        # value and decrypt it
+        # value and decrypt it.
         one_time_pad = masked_token[0...AUTHENTICITY_TOKEN_LENGTH]
         encrypted_csrf_token = masked_token[AUTHENTICITY_TOKEN_LENGTH..-1]
         xor_byte_strings(one_time_pad, encrypted_csrf_token)
       end
 
-      def compare_with_real_token(token, session)
-        ActiveSupport::SecurityUtils.secure_compare(token, real_csrf_token(session))
+      def compare_with_real_token(token, session) # :doc:
+        ActiveSupport::SecurityUtils.fixed_length_secure_compare(token, real_csrf_token(session))
       end
 
-      def valid_per_form_csrf_token?(token, session)
+      def valid_per_form_csrf_token?(token, session) # :doc:
         if per_form_csrf_tokens
           correct_token = per_form_csrf_token(
             session,
@@ -360,18 +380,18 @@ module ActionController #:nodoc:
             request.request_method
           )
 
-          ActiveSupport::SecurityUtils.secure_compare(token, correct_token)
+          ActiveSupport::SecurityUtils.fixed_length_secure_compare(token, correct_token)
         else
           false
         end
       end
 
-      def real_csrf_token(session)
+      def real_csrf_token(session) # :doc:
         session[:_csrf_token] ||= SecureRandom.base64(AUTHENTICITY_TOKEN_LENGTH)
         Base64.strict_decode64(session[:_csrf_token])
       end
 
-      def per_form_csrf_token(session, action_path, method)
+      def per_form_csrf_token(session, action_path, method) # :doc:
         OpenSSL::HMAC.digest(
           OpenSSL::Digest::SHA256.new,
           real_csrf_token(session),
@@ -379,36 +399,46 @@ module ActionController #:nodoc:
         )
       end
 
-      def xor_byte_strings(s1, s2)
+      def xor_byte_strings(s1, s2) # :doc:
         s2_bytes = s2.bytes
         s1.each_byte.with_index { |c1, i| s2_bytes[i] ^= c1 }
-        s2_bytes.pack('C*')
+        s2_bytes.pack("C*")
       end
 
       # The form's authenticity parameter. Override to provide your own.
-      def form_authenticity_param
+      def form_authenticity_param # :doc:
         params[request_forgery_protection_token]
       end
 
       # Checks if the controller allows forgery protection.
-      def protect_against_forgery?
+      def protect_against_forgery? # :doc:
         allow_forgery_protection
       end
 
+      NULL_ORIGIN_MESSAGE = <<-MSG.strip_heredoc
+        The browser returned a 'null' origin for a request with origin-based forgery protection turned on. This usually
+        means you have the 'no-referrer' Referrer-Policy header enabled, or that you the request came from a site that
+        refused to give its origin. This makes it impossible for Rails to verify the source of the requests. Likely the
+        best solution is to change your referrer policy to something less strict like same-origin or strict-same-origin.
+        If you cannot change the referrer policy, you can disable origin checking with the
+        Rails.application.config.action_controller.forgery_protection_origin_check setting.
+      MSG
+
       # Checks if the request originated from the same origin by looking at the
       # Origin header.
-      def valid_request_origin?
+      def valid_request_origin? # :doc:
         if forgery_protection_origin_check
           # We accept blank origin headers because some user agents don't send it.
+          raise InvalidAuthenticityToken, NULL_ORIGIN_MESSAGE if request.origin == "null"
           request.origin.nil? || request.origin == request.base_url
         else
           true
         end
       end
 
-      def normalize_action_path(action_path)
+      def normalize_action_path(action_path) # :doc:
         uri = URI.parse(action_path)
-        uri.path.chomp('/')
+        uri.path.chomp("/")
       end
   end
 end
diff --git a/actionpack/lib/action_controller/metal/rescue.rb b/actionpack/lib/action_controller/metal/rescue.rb
index 17f4030f25..44f7fb7a07 100644
--- a/actionpack/lib/action_controller/metal/rescue.rb
+++ b/actionpack/lib/action_controller/metal/rescue.rb
@@ -1,5 +1,7 @@
+# frozen_string_literal: true
+
 module ActionController #:nodoc:
-  # This module is responsible for providing `rescue_from` helpers
+  # This module is responsible for providing +rescue_from+ helpers
   # to controllers and configuring when detailed exceptions must be
   # shown.
   module Rescue
@@ -8,9 +10,9 @@ module ActionController #:nodoc:
 
     # Override this method if you want to customize when detailed
     # exceptions must be shown. This method is only called when
-    # consider_all_requests_local is false. By default, it returns
-    # false, but someone may set it to `request.local?` so local
-    # requests in production still shows the detailed exception pages.
+    # +consider_all_requests_local+ is +false+. By default, it returns
+    # +false+, but someone may set it to <tt>request.local?</tt> so local
+    # requests in production still show the detailed exception pages.
     def show_detailed_exceptions?
       false
     end
@@ -19,7 +21,7 @@ module ActionController #:nodoc:
       def process_action(*args)
         super
       rescue Exception => exception
-        request.env['action_dispatch.show_detailed_exceptions'] ||= show_detailed_exceptions?
+        request.env["action_dispatch.show_detailed_exceptions"] ||= show_detailed_exceptions?
         rescue_with_handler(exception) || raise
       end
   end
diff --git a/actionpack/lib/action_controller/metal/streaming.rb b/actionpack/lib/action_controller/metal/streaming.rb
index a6115674aa..8dc01a5eb9 100644
--- a/actionpack/lib/action_controller/metal/streaming.rb
+++ b/actionpack/lib/action_controller/metal/streaming.rb
@@ -1,9 +1,11 @@
-require 'rack/chunked'
+# frozen_string_literal: true
+
+require "rack/chunked"
 
 module ActionController #:nodoc:
   # Allows views to be streamed back to the client as they are rendered.
   #
-  # The default way Rails renders views is by first rendering the template
+  # By default, Rails renders views by first rendering the template
   # and then the layout. The response is sent to the client after the whole
   # template is rendered, all queries are made, and the layout is processed.
   #
@@ -181,7 +183,7 @@ module ActionController #:nodoc:
   #   unicorn_rails --config-file unicorn.config.rb
   #
   # You may also want to configure other parameters like <tt>:tcp_nodelay</tt>.
-  # Please check its documentation for more information: http://unicorn.bogomips.org/Unicorn/Configurator.html#method-i-listen
+  # Please check its documentation for more information: https://bogomips.org/unicorn/Unicorn/Configurator.html#method-i-listen
   #
   # If you are using Unicorn with NGINX, you may need to tweak NGINX.
   # Streaming should work out of the box on Rainbows.
@@ -193,10 +195,10 @@ module ActionController #:nodoc:
   module Streaming
     extend ActiveSupport::Concern
 
-    protected
+    private
 
       # Set proper cache control and transfer encoding when streaming
-      def _process_options(options) #:nodoc:
+      def _process_options(options)
         super
         if options[:stream]
           if request.version == "HTTP/1.0"
@@ -210,7 +212,7 @@ module ActionController #:nodoc:
       end
 
       # Call render_body if we are streaming instead of usual +render+.
-      def _render_template(options) #:nodoc:
+      def _render_template(options)
         if options.delete(:stream)
           Rack::Chunked::Body.new view_renderer.render_body(view_context, options)
         else
diff --git a/actionpack/lib/action_controller/metal/strong_parameters.rb b/actionpack/lib/action_controller/metal/strong_parameters.rb
index 46589901fd..a56ac749f8 100644
--- a/actionpack/lib/action_controller/metal/strong_parameters.rb
+++ b/actionpack/lib/action_controller/metal/strong_parameters.rb
@@ -1,12 +1,16 @@
-require 'active_support/core_ext/hash/indifferent_access'
-require 'active_support/core_ext/hash/transform_values'
-require 'active_support/core_ext/array/wrap'
-require 'active_support/core_ext/string/filters'
-require 'active_support/rescuable'
-require 'action_dispatch/http/upload'
-require 'rack/test'
-require 'stringio'
-require 'set'
+# frozen_string_literal: true
+
+require "active_support/core_ext/hash/indifferent_access"
+require "active_support/core_ext/hash/transform_values"
+require "active_support/core_ext/array/wrap"
+require "active_support/core_ext/string/filters"
+require "active_support/core_ext/object/to_query"
+require "active_support/rescuable"
+require "action_dispatch/http/upload"
+require "rack/test"
+require "stringio"
+require "set"
+require "yaml"
 
 module ActionController
   # Raised when a required parameter is missing.
@@ -31,13 +35,25 @@ module ActionController
   #
   #   params = ActionController::Parameters.new(a: "123", b: "456")
   #   params.permit(:c)
-  #   # => ActionController::UnpermittedParameters: found unpermitted parameters: a, b
+  #   # => ActionController::UnpermittedParameters: found unpermitted parameters: :a, :b
   class UnpermittedParameters < IndexError
     attr_reader :params # :nodoc:
 
     def initialize(params) # :nodoc:
       @params = params
-      super("found unpermitted parameter#{'s' if params.size > 1 }: #{params.join(", ")}")
+      super("found unpermitted parameter#{'s' if params.size > 1 }: #{params.map { |e| ":#{e}" }.join(", ")}")
+    end
+  end
+
+  # Raised when a Parameters instance is not marked as permitted and
+  # an operation to transform it to hash is called.
+  #
+  #   params = ActionController::Parameters.new(a: "123", b: "456")
+  #   params.to_h
+  #   # => ActionController::UnfilteredParameters: unable to convert unpermitted parameters to hash
+  class UnfilteredParameters < ArgumentError
+    def initialize # :nodoc:
+      super("unable to convert unpermitted parameters to hash")
     end
   end
 
@@ -51,15 +67,14 @@ module ActionController
   #
   #   params = ActionController::Parameters.new({
   #     person: {
-  #       name: 'Francesco',
+  #       name: "Francesco",
   #       age:  22,
-  #       role: 'admin'
+  #       role: "admin"
   #     }
   #   })
   #
   #   permitted = params.require(:person).permit(:name, :age)
-  #   permitted            # => {"name"=>"Francesco", "age"=>22}
-  #   permitted.class      # => ActionController::Parameters
+  #   permitted            # => <ActionController::Parameters {"name"=>"Francesco", "age"=>22} permitted: true>
   #   permitted.permitted? # => true
   #
   #   Person.first.update!(permitted)
@@ -70,8 +85,8 @@ module ActionController
   # * +permit_all_parameters+ - If it's +true+, all the parameters will be
   #   permitted by default. The default is +false+.
   # * +action_on_unpermitted_parameters+ - Allow to control the behavior when parameters
-  #   that are not explicitly permitted are found. The values can be <tt>:log</tt> to
-  #   write a message on the logger or <tt>:raise</tt> to raise
+  #   that are not explicitly permitted are found. The values can be +false+ to just filter them
+  #   out, <tt>:log</tt> to additionally write a message on the logger, or <tt>:raise</tt> to raise
   #   ActionController::UnpermittedParameters exception. The default value is <tt>:log</tt>
   #   in test and development environments, +false+ otherwise.
   #
@@ -87,7 +102,7 @@ module ActionController
   #
   #   params = ActionController::Parameters.new(a: "123", b: "456")
   #   params.permit(:c)
-  #   # => {}
+  #   # => <ActionController::Parameters {} permitted: true>
   #
   #   ActionController::Parameters.action_on_unpermitted_parameters = :raise
   #
@@ -102,15 +117,95 @@ module ActionController
   # You can fetch values of <tt>ActionController::Parameters</tt> using either
   # <tt>:key</tt> or <tt>"key"</tt>.
   #
-  #   params = ActionController::Parameters.new(key: 'value')
+  #   params = ActionController::Parameters.new(key: "value")
   #   params[:key]  # => "value"
   #   params["key"] # => "value"
   class Parameters
-    cattr_accessor :permit_all_parameters, instance_accessor: false
+    cattr_accessor :permit_all_parameters, instance_accessor: false, default: false
+
     cattr_accessor :action_on_unpermitted_parameters, instance_accessor: false
 
+    ##
+    # :method: as_json
+    #
+    # :call-seq:
+    #   as_json(options=nil)
+    #
+    # Returns a hash that can be used as the JSON representation for the parameters.
+
+    ##
+    # :method: empty?
+    #
+    # :call-seq:
+    #   empty?()
+    #
+    # Returns true if the parameters have no key/value pairs.
+
+    ##
+    # :method: has_key?
+    #
+    # :call-seq:
+    #   has_key?(key)
+    #
+    # Returns true if the given key is present in the parameters.
+
+    ##
+    # :method: has_value?
+    #
+    # :call-seq:
+    #   has_value?(value)
+    #
+    # Returns true if the given value is present for some key in the parameters.
+
+    ##
+    # :method: include?
+    #
+    # :call-seq:
+    #   include?(key)
+    #
+    # Returns true if the given key is present in the parameters.
+
+    ##
+    # :method: key?
+    #
+    # :call-seq:
+    #   key?(key)
+    #
+    # Returns true if the given key is present in the parameters.
+
+    ##
+    # :method: keys
+    #
+    # :call-seq:
+    #   keys()
+    #
+    # Returns a new array of the keys of the parameters.
+
+    ##
+    # :method: to_s
+    #
+    # :call-seq:
+    #   to_s()
+    #
+    # Returns the content of the parameters as a string.
+
+    ##
+    # :method: value?
+    #
+    # :call-seq:
+    #   value?(value)
+    #
+    # Returns true if the given value is present for some key in the parameters.
+
+    ##
+    # :method: values
+    #
+    # :call-seq:
+    #   values()
+    #
+    # Returns a new array of the values of the parameters.
     delegate :keys, :key?, :has_key?, :values, :has_value?, :value?, :empty?, :include?,
-      :as_json, to: :@parameters
+      :as_json, :to_s, to: :@parameters
 
     # By default, never raise an UnpermittedParameters exception if these
     # params are present. The default includes both 'controller' and 'action'
@@ -119,8 +214,7 @@ module ActionController
     # config. For instance:
     #
     #    config.always_permitted_parameters = %w( controller action format )
-    cattr_accessor :always_permitted_parameters
-    self.always_permitted_parameters = %w( controller action )
+    cattr_accessor :always_permitted_parameters, default: %w( controller action )
 
     # Returns a new instance of <tt>ActionController::Parameters</tt>.
     # Also, sets the +permitted+ attribute to the default value of
@@ -129,13 +223,13 @@ module ActionController
     #   class Person < ActiveRecord::Base
     #   end
     #
-    #   params = ActionController::Parameters.new(name: 'Francesco')
+    #   params = ActionController::Parameters.new(name: "Francesco")
     #   params.permitted?  # => false
     #   Person.new(params) # => ActiveModel::ForbiddenAttributesError
     #
     #   ActionController::Parameters.permit_all_parameters = true
     #
-    #   params = ActionController::Parameters.new(name: 'Francesco')
+    #   params = ActionController::Parameters.new(name: "Francesco")
     #   params.permitted?  # => true
     #   Person.new(params) # => #<Person id: nil, name: "Francesco">
     def initialize(parameters = {})
@@ -147,29 +241,21 @@ module ActionController
     # permitted flag.
     def ==(other)
       if other.respond_to?(:permitted?)
-        self.permitted? == other.permitted? && self.parameters == other.parameters
-      elsif other.is_a?(Hash)
-        ActiveSupport::Deprecation.warn <<-WARNING.squish
-          Comparing equality between `ActionController::Parameters` and a
-          `Hash` is deprecated and will be removed in Rails 5.1. Please only do
-          comparisons between instances of `ActionController::Parameters`. If
-          you need to compare to a hash, first convert it using
-          `ActionController::Parameters#new`.
-        WARNING
-        @parameters == other.with_indifferent_access
+        permitted? == other.permitted? && parameters == other.parameters
       else
         @parameters == other
       end
     end
 
     # Returns a safe <tt>ActiveSupport::HashWithIndifferentAccess</tt>
-    # representation of this parameter with all unpermitted keys removed.
+    # representation of the parameters with all unpermitted keys removed.
     #
     #   params = ActionController::Parameters.new({
-    #     name: 'Senjougahara Hitagi',
-    #     oddity: 'Heavy stone crab'
+    #     name: "Senjougahara Hitagi",
+    #     oddity: "Heavy stone crab"
     #   })
-    #   params.to_h # => {}
+    #   params.to_h
+    #   # => ActionController::UnfilteredParameters: unable to convert unpermitted parameters to hash
     #
     #   safe_params = params.permit(:name)
     #   safe_params.to_h # => {"name"=>"Senjougahara Hitagi"}
@@ -177,17 +263,66 @@ module ActionController
       if permitted?
         convert_parameters_to_hashes(@parameters, :to_h)
       else
-        slice(*self.class.always_permitted_parameters).permit!.to_h
+        raise UnfilteredParameters
       end
     end
 
+    # Returns a safe <tt>Hash</tt> representation of the parameters
+    # with all unpermitted keys removed.
+    #
+    #   params = ActionController::Parameters.new({
+    #     name: "Senjougahara Hitagi",
+    #     oddity: "Heavy stone crab"
+    #   })
+    #   params.to_hash
+    #   # => ActionController::UnfilteredParameters: unable to convert unpermitted parameters to hash
+    #
+    #   safe_params = params.permit(:name)
+    #   safe_params.to_hash # => {"name"=>"Senjougahara Hitagi"}
+    def to_hash
+      to_h.to_hash
+    end
+
+    # Returns a string representation of the receiver suitable for use as a URL
+    # query string:
+    #
+    #   params = ActionController::Parameters.new({
+    #     name: "David",
+    #     nationality: "Danish"
+    #   })
+    #   params.to_query
+    #   # => ActionController::UnfilteredParameters: unable to convert unpermitted parameters to hash
+    #
+    #   safe_params = params.permit(:name, :nationality)
+    #   safe_params.to_query
+    #   # => "name=David&nationality=Danish"
+    #
+    # An optional namespace can be passed to enclose key names:
+    #
+    #   params = ActionController::Parameters.new({
+    #     name: "David",
+    #     nationality: "Danish"
+    #   })
+    #   safe_params = params.permit(:name, :nationality)
+    #   safe_params.to_query("user")
+    #   # => "user%5Bname%5D=David&user%5Bnationality%5D=Danish"
+    #
+    # The string pairs "key=value" that conform the query string
+    # are sorted lexicographically in ascending order.
+    #
+    # This method is also aliased as +to_param+.
+    def to_query(*args)
+      to_h.to_query(*args)
+    end
+    alias_method :to_param, :to_query
+
     # Returns an unsafe, unfiltered
-    # <tt>ActiveSupport::HashWithIndifferentAccess</tt> representation of this
-    # parameter.
+    # <tt>ActiveSupport::HashWithIndifferentAccess</tt> representation of the
+    # parameters.
     #
     #   params = ActionController::Parameters.new({
-    #     name: 'Senjougahara Hitagi',
-    #     oddity: 'Heavy stone crab'
+    #     name: "Senjougahara Hitagi",
+    #     oddity: "Heavy stone crab"
     #   })
     #   params.to_unsafe_h
     #   # => {"name"=>"Senjougahara Hitagi", "oddity" => "Heavy stone crab"}
@@ -197,10 +332,10 @@ module ActionController
     alias_method :to_unsafe_hash, :to_unsafe_h
 
     # Convert all hashes in values into parameters, then yield each pair in
-    # the same way as <tt>Hash#each_pair</tt>
+    # the same way as <tt>Hash#each_pair</tt>.
     def each_pair(&block)
       @parameters.each_pair do |key, value|
-        yield key, convert_hashes_to_parameters(key, value)
+        yield [key, convert_hashes_to_parameters(key, value)]
       end
     end
     alias_method :each, :each_pair
@@ -232,7 +367,7 @@ module ActionController
     #   class Person < ActiveRecord::Base
     #   end
     #
-    #   params = ActionController::Parameters.new(name: 'Francesco')
+    #   params = ActionController::Parameters.new(name: "Francesco")
     #   params.permitted?  # => false
     #   Person.new(params) # => ActiveModel::ForbiddenAttributesError
     #   params.permit!
@@ -254,8 +389,8 @@ module ActionController
     # When passed a single key, if it exists and its associated value is
     # either present or the singleton +false+, returns said value:
     #
-    #   ActionController::Parameters.new(person: { name: 'Francesco' }).require(:person)
-    #   # => {"name"=>"Francesco"}
+    #   ActionController::Parameters.new(person: { name: "Francesco" }).require(:person)
+    #   # => <ActionController::Parameters {"name"=>"Francesco"} permitted: false>
     #
     # Otherwise raises <tt>ActionController::ParameterMissing</tt>:
     #
@@ -276,18 +411,18 @@ module ActionController
     # returned:
     #
     #   params = ActionController::Parameters.new(user: { ... }, profile: { ... })
-    #   user_params, profile_params = params.require(:user, :profile)
+    #   user_params, profile_params = params.require([:user, :profile])
     #
     # Otherwise, the method re-raises the first exception found:
     #
     #   params = ActionController::Parameters.new(user: {}, profile: {})
-    #   user_params, profile_params = params.require(:user, :profile)
+    #   user_params, profile_params = params.require([:user, :profile])
     #   # ActionController::ParameterMissing: param is missing or the value is empty: user
     #
     # Technically this method can be used to fetch terminal values:
     #
     #   # CAREFUL
-    #   params = ActionController::Parameters.new(person: { name: 'Finn' })
+    #   params = ActionController::Parameters.new(person: { name: "Finn" })
     #   name = params.require(:person).require(:name) # CAREFUL
     #
     # but take into account that at some point those ones have to be permitted:
@@ -317,7 +452,7 @@ module ActionController
     # for the object to +true+. This is useful for limiting which attributes
     # should be allowed for mass updating.
     #
-    #   params = ActionController::Parameters.new(user: { name: 'Francesco', age: 22, role: 'admin' })
+    #   params = ActionController::Parameters.new(user: { name: "Francesco", age: 22, role: "admin" })
     #   permitted = params.require(:user).permit(:name, :age)
     #   permitted.permitted?      # => true
     #   permitted.has_key?(:name) # => true
@@ -337,18 +472,27 @@ module ActionController
     # You may declare that the parameter should be an array of permitted scalars
     # by mapping it to an empty array:
     #
-    #   params = ActionController::Parameters.new(tags: ['rails', 'parameters'])
+    #   params = ActionController::Parameters.new(tags: ["rails", "parameters"])
     #   params.permit(tags: [])
     #
+    # Sometimes it is not possible or convenient to declare the valid keys of
+    # a hash parameter or its internal structure. Just map to an empty hash:
+    #
+    #   params.permit(preferences: {})
+    #
+    # Be careful because this opens the door to arbitrary input. In this
+    # case, +permit+ ensures values in the returned structure are permitted
+    # scalars and filters out anything else.
+    #
     # You can also use +permit+ on nested parameters, like:
     #
     #   params = ActionController::Parameters.new({
     #     person: {
-    #       name: 'Francesco',
+    #       name: "Francesco",
     #       age:  22,
     #       pets: [{
-    #         name: 'Purplish',
-    #         category: 'dogs'
+    #         name: "Purplish",
+    #         category: "dogs"
     #       }]
     #     }
     #   })
@@ -367,20 +511,20 @@ module ActionController
     #   params = ActionController::Parameters.new({
     #     person: {
     #       contact: {
-    #         email: 'none@test.com',
-    #         phone: '555-1234'
+    #         email: "none@test.com",
+    #         phone: "555-1234"
     #       }
     #     }
     #   })
     #
     #   params.require(:person).permit(:contact)
-    #   # => {}
+    #   # => <ActionController::Parameters {} permitted: true>
     #
     #   params.require(:person).permit(contact: :phone)
-    #   # => {"contact"=>{"phone"=>"555-1234"}}
+    #   # => <ActionController::Parameters {"contact"=><ActionController::Parameters {"phone"=>"555-1234"} permitted: true>} permitted: true>
     #
     #   params.require(:person).permit(contact: [ :email, :phone ])
-    #   # => {"contact"=>{"email"=>"none@test.com", "phone"=>"555-1234"}}
+    #   # => <ActionController::Parameters {"contact"=><ActionController::Parameters {"email"=>"none@test.com", "phone"=>"555-1234"} permitted: true>} permitted: true>
     def permit(*filters)
       params = self.class.new
 
@@ -388,7 +532,7 @@ module ActionController
         case filter
         when Symbol, String
           permitted_scalar_filter(params, filter)
-        when Hash then
+        when Hash
           hash_filter(params, filter)
         end
       end
@@ -401,8 +545,8 @@ module ActionController
     # Returns a parameter for the given +key+. If not found,
     # returns +nil+.
     #
-    #   params = ActionController::Parameters.new(person: { name: 'Francesco' })
-    #   params[:person] # => {"name"=>"Francesco"}
+    #   params = ActionController::Parameters.new(person: { name: "Francesco" })
+    #   params[:person] # => <ActionController::Parameters {"name"=>"Francesco"} permitted: false>
     #   params[:none]   # => nil
     def [](key)
       convert_hashes_to_parameters(key, @parameters[key])
@@ -420,11 +564,11 @@ module ActionController
     # if more arguments are given, then that will be returned; if a block
     # is given, then that will be run and its result returned.
     #
-    #   params = ActionController::Parameters.new(person: { name: 'Francesco' })
-    #   params.fetch(:person)               # => {"name"=>"Francesco"}
+    #   params = ActionController::Parameters.new(person: { name: "Francesco" })
+    #   params.fetch(:person)               # => <ActionController::Parameters {"name"=>"Francesco"} permitted: false>
     #   params.fetch(:none)                 # => ActionController::ParameterMissing: param is missing or the value is empty: none
-    #   params.fetch(:none, 'Francesco')    # => "Francesco"
-    #   params.fetch(:none) { 'Francesco' } # => "Francesco"
+    #   params.fetch(:none, "Francesco")    # => "Francesco"
+    #   params.fetch(:none) { "Francesco" } # => "Francesco"
     def fetch(key, *args)
       convert_value_to_parameters(
         @parameters.fetch(key) {
@@ -457,8 +601,8 @@ module ActionController
     # don't exist, returns an empty hash.
     #
     #   params = ActionController::Parameters.new(a: 1, b: 2, c: 3)
-    #   params.slice(:a, :b) # => {"a"=>1, "b"=>2}
-    #   params.slice(:d)     # => {}
+    #   params.slice(:a, :b) # => <ActionController::Parameters {"a"=>1, "b"=>2} permitted: false>
+    #   params.slice(:d)     # => <ActionController::Parameters {} permitted: false>
     def slice(*keys)
       new_instance_with_inherited_permitted_status(@parameters.slice(*keys))
     end
@@ -474,8 +618,8 @@ module ActionController
     # filters out the given +keys+.
     #
     #   params = ActionController::Parameters.new(a: 1, b: 2, c: 3)
-    #   params.except(:a, :b) # => {"c"=>3}
-    #   params.except(:d)     # => {"a"=>1,"b"=>2,"c"=>3}
+    #   params.except(:a, :b) # => <ActionController::Parameters {"c"=>3} permitted: false>
+    #   params.except(:d)     # => <ActionController::Parameters {"a"=>1, "b"=>2, "c"=>3} permitted: false>
     def except(*keys)
       new_instance_with_inherited_permitted_status(@parameters.except(*keys))
     end
@@ -483,8 +627,8 @@ module ActionController
     # Removes and returns the key/value pairs matching the given keys.
     #
     #   params = ActionController::Parameters.new(a: 1, b: 2, c: 3)
-    #   params.extract!(:a, :b) # => {"a"=>1, "b"=>2}
-    #   params                  # => {"c"=>3}
+    #   params.extract!(:a, :b) # => <ActionController::Parameters {"a"=>1, "b"=>2} permitted: false>
+    #   params                  # => <ActionController::Parameters {"c"=>3} permitted: false>
     def extract!(*keys)
       new_instance_with_inherited_permitted_status(@parameters.extract!(*keys))
     end
@@ -494,7 +638,7 @@ module ActionController
     #
     #   params = ActionController::Parameters.new(a: 1, b: 2, c: 3)
     #   params.transform_values { |x| x * 2 }
-    #   # => {"a"=>2, "b"=>4, "c"=>6}
+    #   # => <ActionController::Parameters {"a"=>2, "b"=>4, "c"=>6} permitted: false>
     def transform_values(&block)
       if block
         new_instance_with_inherited_permitted_status(
@@ -531,12 +675,12 @@ module ActionController
       self
     end
 
-    # Deletes and returns a key-value pair from +Parameters+ whose key is equal
-    # to key. If the key is not found, returns the default value. If the
-    # optional code block is given and the key is not found, pass in the key
-    # and return the result of block.
-    def delete(key)
-      convert_value_to_parameters(@parameters.delete(key))
+    # Deletes a key-value pair from +Parameters+ and returns the value. If
+    # +key+ is not found, returns +nil+ (or, with optional code block, yields
+    # +key+ and returns the result). Cf. +#extract!+, which returns the
+    # corresponding +ActionController::Parameters+ object.
+    def delete(key, &block)
+      convert_value_to_parameters(@parameters.delete(key, &block))
     end
 
     # Returns a new instance of <tt>ActionController::Parameters</tt> with only
@@ -545,7 +689,7 @@ module ActionController
       new_instance_with_inherited_permitted_status(@parameters.select(&block))
     end
 
-    # Equivalent to Hash#keep_if, but returns nil if no changes were made.
+    # Equivalent to Hash#keep_if, but returns +nil+ if no changes were made.
     def select!(&block)
       @parameters.select!(&block)
       self
@@ -571,27 +715,37 @@ module ActionController
       convert_value_to_parameters(@parameters.values_at(*keys))
     end
 
-    # Returns an exact copy of the <tt>ActionController::Parameters</tt>
-    # instance. +permitted+ state is kept on the duped object.
-    #
-    #   params = ActionController::Parameters.new(a: 1)
-    #   params.permit!
-    #   params.permitted?        # => true
-    #   copy_params = params.dup # => {"a"=>1}
-    #   copy_params.permitted?   # => true
-    def dup
-      super.tap do |duplicate|
-        duplicate.permitted = @permitted
-      end
+    # Returns a new <tt>ActionController::Parameters</tt> with all keys from
+    # +other_hash+ merged into current hash.
+    def merge(other_hash)
+      new_instance_with_inherited_permitted_status(
+        @parameters.merge(other_hash.to_h)
+      )
+    end
+
+    # Returns current <tt>ActionController::Parameters</tt> instance with
+    # +other_hash+ merged into current hash.
+    def merge!(other_hash)
+      @parameters.merge!(other_hash.to_h)
+      self
     end
 
     # Returns a new <tt>ActionController::Parameters</tt> with all keys from
-    # +other_hash+ merges into current hash.
-    def merge(other_hash)
+    # current hash merged into +other_hash+.
+    def reverse_merge(other_hash)
       new_instance_with_inherited_permitted_status(
-        @parameters.merge(other_hash)
+        other_hash.to_h.merge(@parameters)
       )
     end
+    alias_method :with_defaults, :reverse_merge
+
+    # Returns current <tt>ActionController::Parameters</tt> instance with
+    # current hash merged into +other_hash+.
+    def reverse_merge!(other_hash)
+      @parameters.merge!(other_hash.to_h) { |key, left, right| left }
+      self
+    end
+    alias_method :with_defaults!, :reverse_merge!
 
     # This is required by ActiveModel attribute assignment, so that user can
     # pass +Parameters+ to a mass assignment methods in a model. It should not
@@ -604,21 +758,37 @@ module ActionController
       "<#{self.class} #{@parameters} permitted: #{@permitted}>"
     end
 
-    def method_missing(method_sym, *args, &block)
-      if @parameters.respond_to?(method_sym)
-        message = <<-DEPRECATE.squish
-          Method #{method_sym} is deprecated and will be removed in Rails 5.1,
-          as `ActionController::Parameters` no longer inherits from
-          hash. Using this deprecated behavior exposes potential security
-          problems. If you continue to use this method you may be creating
-          a security vulnerability in your app that can be exploited. Instead,
-          consider using one of these documented methods which are not
-          deprecated: http://api.rubyonrails.org/v#{ActionPack.version}/classes/ActionController/Parameters.html
-        DEPRECATE
-        ActiveSupport::Deprecation.warn(message)
-        @parameters.public_send(method_sym, *args, &block)
-      else
-        super
+    def self.hook_into_yaml_loading # :nodoc:
+      # Wire up YAML format compatibility with Rails 4.2 and Psych 2.0.8 and 2.0.9+.
+      # Makes the YAML parser call `init_with` when it encounters the keys below
+      # instead of trying its own parsing routines.
+      YAML.load_tags["!ruby/hash-with-ivars:ActionController::Parameters"] = name
+      YAML.load_tags["!ruby/hash:ActionController::Parameters"] = name
+    end
+    hook_into_yaml_loading
+
+    def init_with(coder) # :nodoc:
+      case coder.tag
+      when "!ruby/hash:ActionController::Parameters"
+        # YAML 2.0.8's format where hash instance variables weren't stored.
+        @parameters = coder.map.with_indifferent_access
+        @permitted  = false
+      when "!ruby/hash-with-ivars:ActionController::Parameters"
+        # YAML 2.0.9's Hash subclass format where keys and values
+        # were stored under an elements hash and `permitted` within an ivars hash.
+        @parameters = coder.map["elements"].with_indifferent_access
+        @permitted  = coder.map["ivars"][:@permitted]
+      when "!ruby/object:ActionController::Parameters"
+        # YAML's Object format. Only needed because of the format
+        # backwardscompability above, otherwise equivalent to YAML's initialization.
+        @parameters, @permitted = coder.map["parameters"], coder.map["permitted"]
+      end
+    end
+
+    # Returns duplicate of object including all parameters.
+    def deep_dup
+      self.class.new(@parameters.deep_dup).tap do |duplicate|
+        duplicate.permitted = @permitted
       end
     end
 
@@ -682,7 +852,7 @@ module ActionController
         when Parameters
           if object.fields_for_style?
             hash = object.class.new
-            object.each { |k,v| hash[k] = yield v }
+            object.each { |k, v| hash[k] = yield v }
             hash
           else
             yield object
@@ -704,7 +874,7 @@ module ActionController
       end
 
       def unpermitted_keys(params)
-        self.keys - params.keys - self.always_permitted_parameters
+        keys - params.keys - always_permitted_parameters
       end
 
       #
@@ -735,7 +905,7 @@ module ActionController
       ]
 
       def permitted_scalar?(value)
-        PERMITTED_SCALAR_TYPES.any? {|type| value.is_a?(type)}
+        PERMITTED_SCALAR_TYPES.any? { |type| value.is_a?(type) }
       end
 
       def permitted_scalar_filter(params, key)
@@ -751,7 +921,7 @@ module ActionController
       end
 
       def array_of_permitted_scalars?(value)
-        if value.is_a?(Array) && value.all? {|element| permitted_scalar?(element)}
+        if value.is_a?(Array) && value.all? { |element| permitted_scalar?(element) }
           yield value
         end
       end
@@ -761,6 +931,7 @@ module ActionController
       end
 
       EMPTY_ARRAY = []
+      EMPTY_HASH  = {}
       def hash_filter(params, filter)
         filter = filter.with_indifferent_access
 
@@ -774,6 +945,11 @@ module ActionController
             array_of_permitted_scalars?(self[key]) do |val|
               params[key] = val
             end
+          elsif filter[key] == EMPTY_HASH
+            # Declaration { preferences: {} }.
+            if value.is_a?(Parameters)
+              params[key] = permit_any_in_parameters(value)
+            end
           elsif non_scalar?(value)
             # Declaration { user: :name } or { user: [:name, :age, { address: ... }] }.
             params[key] = each_element(value) do |element|
@@ -782,6 +958,43 @@ module ActionController
           end
         end
       end
+
+      def permit_any_in_parameters(params)
+        self.class.new.tap do |sanitized|
+          params.each do |key, value|
+            case value
+            when ->(v) { permitted_scalar?(v) }
+              sanitized[key] = value
+            when Array
+              sanitized[key] = permit_any_in_array(value)
+            when Parameters
+              sanitized[key] = permit_any_in_parameters(value)
+            else
+              # Filter this one out.
+            end
+          end
+        end
+      end
+
+      def permit_any_in_array(array)
+        [].tap do |sanitized|
+          array.each do |element|
+            case element
+            when ->(e) { permitted_scalar?(e) }
+              sanitized << element
+            when Parameters
+              sanitized << permit_any_in_parameters(element)
+            else
+              # Filter this one out.
+            end
+          end
+        end
+      end
+
+      def initialize_copy(source)
+        super
+        @parameters = @parameters.dup
+      end
   end
 
   # == Strong \Parameters
@@ -792,7 +1005,7 @@ module ActionController
   # whitelisted.
   #
   # In addition, parameters can be marked as required and flow through a
-  # predefined raise/rescue flow to end up as a 400 Bad Request with no
+  # predefined raise/rescue flow to end up as a <tt>400 Bad Request</tt> with no
   # effort.
   #
   #   class PeopleController < ActionController::Base
@@ -805,7 +1018,7 @@ module ActionController
   #     end
   #
   #     # This will pass with flying colors as long as there's a person key in the
-  #     # parameters, otherwise it'll raise an ActionController::MissingParameter
+  #     # parameters, otherwise it'll raise an ActionController::ParameterMissing
   #     # exception, which will get caught by ActionController::Base and turned
   #     # into a 400 Bad Request reply.
   #     def update
@@ -816,7 +1029,7 @@ module ActionController
   #
   #     private
   #       # Using a private method to encapsulate the permissible parameters is
-  #       # just a good pattern since you'll be able to reuse the same permit
+  #       # a good pattern since you'll be able to reuse the same permit
   #       # list between create and update. Also, you can specialize this method
   #       # with per-user checking of permissible attributes.
   #       def person_params
diff --git a/actionpack/lib/action_controller/metal/testing.rb b/actionpack/lib/action_controller/metal/testing.rb
index ac37b00010..6e8a95040f 100644
--- a/actionpack/lib/action_controller/metal/testing.rb
+++ b/actionpack/lib/action_controller/metal/testing.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActionController
   module Testing
     extend ActiveSupport::Concern
@@ -10,11 +12,5 @@ module ActionController
         self.params = nil
       end
     end
-
-    module ClassMethods
-      def before_filters
-        _process_action_callbacks.find_all{|x| x.kind == :before}.map(&:name)
-      end
-    end
   end
 end
diff --git a/actionpack/lib/action_controller/metal/url_for.rb b/actionpack/lib/action_controller/metal/url_for.rb
index dbf7241a14..84dbb59a63 100644
--- a/actionpack/lib/action_controller/metal/url_for.rb
+++ b/actionpack/lib/action_controller/metal/url_for.rb
@@ -1,9 +1,11 @@
+# frozen_string_literal: true
+
 module ActionController
   # Includes +url_for+ into the host class. The class has to provide a +RouteSet+ by implementing
   # the <tt>_routes</tt> method. Otherwise, an exception will be raised.
   #
   # In addition to <tt>AbstractController::UrlFor</tt>, this module accesses the HTTP layer to define
-  # url options like the +host+. In order to do so, this module requires the host class
+  # URL options like the +host+. In order to do so, this module requires the host class
   # to implement +env+ which needs to be Rack-compatible and +request+
   # which is either an instance of +ActionDispatch::Request+ or an object
   # that responds to the +host+, +optional_port+, +protocol+ and
@@ -27,10 +29,10 @@ module ActionController
 
     def url_options
       @_url_options ||= {
-        :host => request.host,
-        :port => request.optional_port,
-        :protocol => request.protocol,
-        :_recall => request.path_parameters
+        host: request.host,
+        port: request.optional_port,
+        protocol: request.protocol,
+        _recall: request.path_parameters
       }.merge!(super).freeze
 
       if (same_origin = _routes.equal?(request.routes)) ||
diff --git a/actionpack/lib/action_controller/railtie.rb b/actionpack/lib/action_controller/railtie.rb
index 28b20052b5..7d42f5d931 100644
--- a/actionpack/lib/action_controller/railtie.rb
+++ b/actionpack/lib/action_controller/railtie.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require "rails"
 require "action_controller"
 require "action_dispatch/railtie"
@@ -11,7 +13,7 @@ module ActionController
 
     config.eager_load_namespaces << ActionController
 
-    initializer "action_controller.assets_config", :group => :all do |app|
+    initializer "action_controller.assets_config", group: :all do |app|
       app.config.action_controller.assets_dir ||= app.config.paths["public"].first
     end
 
@@ -22,13 +24,15 @@ module ActionController
     initializer "action_controller.parameters_config" do |app|
       options = app.config.action_controller
 
-      ActionController::Parameters.permit_all_parameters = options.delete(:permit_all_parameters) { false }
-      if app.config.action_controller[:always_permitted_parameters]
-        ActionController::Parameters.always_permitted_parameters =
-          app.config.action_controller.delete(:always_permitted_parameters)
-      end
-      ActionController::Parameters.action_on_unpermitted_parameters = options.delete(:action_on_unpermitted_parameters) do
-        (Rails.env.test? || Rails.env.development?) ? :log : false
+      ActiveSupport.on_load(:action_controller, run_once: true) do
+        ActionController::Parameters.permit_all_parameters = options.delete(:permit_all_parameters) { false }
+        if app.config.action_controller[:always_permitted_parameters]
+          ActionController::Parameters.always_permitted_parameters =
+            app.config.action_controller.delete(:always_permitted_parameters)
+        end
+        ActionController::Parameters.action_on_unpermitted_parameters = options.delete(:action_on_unpermitted_parameters) do
+          (Rails.env.test? || Rails.env.development?) ? :log : false
+        end
       end
     end
 
@@ -42,7 +46,7 @@ module ActionController
       options.javascripts_dir ||= paths["public/javascripts"].first
       options.stylesheets_dir ||= paths["public/stylesheets"].first
 
-      # Ensure readers methods get compiled
+      # Ensure readers methods get compiled.
       options.asset_host        ||= app.config.asset_host
       options.relative_url_root ||= app.config.relative_url_root
 
@@ -51,7 +55,7 @@ module ActionController
         extend ::AbstractController::Railties::RoutesHelpers.with(app.routes)
         extend ::ActionController::Railties::Helpers
 
-        options.each do |k,v|
+        options.each do |k, v|
           k = "#{k}="
           if respond_to?(k)
             send(k, v)
@@ -67,5 +71,19 @@ module ActionController
         config.compile_methods! if config.respond_to?(:compile_methods!)
       end
     end
+
+    initializer "action_controller.request_forgery_protection" do |app|
+      ActiveSupport.on_load(:action_controller_base) do
+        if app.config.action_controller.default_protect_from_forgery
+          protect_from_forgery with: :exception
+        end
+      end
+    end
+
+    initializer "action_controller.eager_load_actions" do
+      ActiveSupport.on_load(:after_initialize) do
+        ActionController::Metal.descendants.each(&:action_methods) if config.eager_load
+      end
+    end
   end
 end
diff --git a/actionpack/lib/action_controller/railties/helpers.rb b/actionpack/lib/action_controller/railties/helpers.rb
index 3985c6b273..fa746fa9e8 100644
--- a/actionpack/lib/action_controller/railties/helpers.rb
+++ b/actionpack/lib/action_controller/railties/helpers.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActionController
   module Railties
     module Helpers
diff --git a/actionpack/lib/action_controller/renderer.rb b/actionpack/lib/action_controller/renderer.rb
index a8c8d66682..49c5b782f0 100644
--- a/actionpack/lib/action_controller/renderer.rb
+++ b/actionpack/lib/action_controller/renderer.rb
@@ -1,11 +1,13 @@
-require 'active_support/core_ext/hash/keys'
+# frozen_string_literal: true
+
+require "active_support/core_ext/hash/keys"
 
 module ActionController
   # ActionController::Renderer allows you to render arbitrary templates
   # without requirement of being in controller actions.
   #
   # You get a concrete renderer class by invoking ActionController::Base#renderer.
-  # For example,
+  # For example:
   #
   #   ApplicationController.renderer
   #
@@ -18,7 +20,7 @@ module ActionController
   #   ApplicationController.render template: '...'
   #
   # #render allows you to use the same options that you can use when rendering in a controller.
-  # For example,
+  # For example:
   #
   #   FooController.render :action, locals: { ... }, assigns: { ... }
   #
@@ -37,11 +39,11 @@ module ActionController
     attr_reader :defaults, :controller
 
     DEFAULTS = {
-      http_host: 'example.org',
+      http_host: "example.org",
       https: false,
-      method: 'get',
-      script_name: '',
-      input: ''
+      method: "get",
+      script_name: "",
+      input: ""
     }.freeze
 
     # Create a new renderer instance for a specific controller class.
@@ -56,11 +58,12 @@ module ActionController
 
     # Create a new renderer for the same controller but with new defaults.
     def with_defaults(defaults)
-      self.class.new controller, env, self.defaults.merge(defaults)
+      self.class.new controller, @env, self.defaults.merge(defaults)
     end
 
     # Accepts a custom Rack environment to render templates in.
-    # It will be merged with ActionController::Renderer.defaults
+    # It will be merged with the default Rack environment defined by
+    # +ActionController::Renderer::DEFAULTS+.
     def initialize(controller, env, defaults)
       @controller = controller
       @defaults = defaults
@@ -69,7 +72,7 @@ module ActionController
 
     # Render templates with any options from ActionController::Base#render_to_string.
     def render(*args)
-      raise 'missing controller' unless controller
+      raise "missing controller" unless controller
 
       request = ActionDispatch::Request.new @env
       request.routes = controller._routes
@@ -83,26 +86,29 @@ module ActionController
     private
       def normalize_keys(env)
         new_env = {}
-        env.each_pair { |k,v| new_env[rack_key_for(k)] = rack_value_for(k, v) }
+        env.each_pair { |k, v| new_env[rack_key_for(k)] = rack_value_for(k, v) }
+        new_env["rack.url_scheme"] = new_env["HTTPS"] == "on" ? "https" : "http"
         new_env
       end
 
       RACK_KEY_TRANSLATION = {
-        http_host:   'HTTP_HOST',
-        https:       'HTTPS',
-        method:      'REQUEST_METHOD',
-        script_name: 'SCRIPT_NAME',
-        input:       'rack.input'
+        http_host:   "HTTP_HOST",
+        https:       "HTTPS",
+        method:      "REQUEST_METHOD",
+        script_name: "SCRIPT_NAME",
+        input:       "rack.input"
       }
 
       IDENTITY = ->(_) { _ }
 
       RACK_VALUE_TRANSLATION = {
-        https: ->(v) { v ? 'on' : 'off' },
+        https: ->(v) { v ? "on" : "off" },
         method: ->(v) { v.upcase },
       }
 
-      def rack_key_for(key); RACK_KEY_TRANSLATION[key]; end
+      def rack_key_for(key)
+        RACK_KEY_TRANSLATION.fetch(key, key.to_s)
+      end
 
       def rack_value_for(key, value)
         RACK_VALUE_TRANSLATION.fetch(key, IDENTITY).call value
diff --git a/actionpack/lib/action_controller/template_assertions.rb b/actionpack/lib/action_controller/template_assertions.rb
index 0179f4afcd..dd83c1a283 100644
--- a/actionpack/lib/action_controller/template_assertions.rb
+++ b/actionpack/lib/action_controller/template_assertions.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActionController
   module TemplateAssertions
     def assert_template(options = {}, message = nil)
diff --git a/actionpack/lib/action_controller/test_case.rb b/actionpack/lib/action_controller/test_case.rb
index b1b3e87934..4b408750a4 100644
--- a/actionpack/lib/action_controller/test_case.rb
+++ b/actionpack/lib/action_controller/test_case.rb
@@ -1,23 +1,26 @@
-require 'rack/session/abstract/id'
-require 'active_support/core_ext/hash/conversions'
-require 'active_support/core_ext/object/to_query'
-require 'active_support/core_ext/module/anonymous'
-require 'active_support/core_ext/hash/keys'
-require 'action_controller/template_assertions'
-require 'rails-dom-testing'
+# frozen_string_literal: true
+
+require "rack/session/abstract/id"
+require "active_support/core_ext/hash/conversions"
+require "active_support/core_ext/object/to_query"
+require "active_support/core_ext/module/anonymous"
+require "active_support/core_ext/module/redefine_method"
+require "active_support/core_ext/hash/keys"
+require "active_support/testing/constant_lookup"
+require "action_controller/template_assertions"
+require "rails-dom-testing"
 
 module ActionController
-  # :stopdoc:
   class Metal
     include Testing::Functional
   end
 
   module Live
-    # Disable controller / rendering threads in tests.  User tests can access
+    # Disable controller / rendering threads in tests. User tests can access
     # the database on the main thread, so they could open a txn, then the
     # controller thread will open a new connection and try to access data
-    # that's only visible to the main thread's txn.  This is the problem in #23483
-    remove_method :new_controller_thread
+    # that's only visible to the main thread's txn. This is the problem in #23483.
+    silence_redefinition_of_method :new_controller_thread
     def new_controller_thread # :nodoc:
       yield
     end
@@ -27,18 +30,20 @@ module ActionController
   # Please use ActionDispatch::IntegrationTest going forward.
   class TestRequest < ActionDispatch::TestRequest #:nodoc:
     DEFAULT_ENV = ActionDispatch::TestRequest::DEFAULT_ENV.dup
-    DEFAULT_ENV.delete 'PATH_INFO'
+    DEFAULT_ENV.delete "PATH_INFO"
 
     def self.new_session
       TestSession.new
     end
 
-    # Create a new test request with default `env` values
-    def self.create
+    attr_reader :controller_class
+
+    # Create a new test request with default `env` values.
+    def self.create(controller_class)
       env = {}
       env = Rails.application.env_config.merge(env) if defined?(Rails.application) && Rails.application
       env["rack.request.cookie_hash"] = {}.with_indifferent_access
-      new(default_env.merge(env), new_session)
+      new(default_env.merge(env), new_session, controller_class)
     end
 
     def self.default_env
@@ -46,13 +51,14 @@ module ActionController
     end
     private_class_method :default_env
 
-    def initialize(env, session)
+    def initialize(env, session, controller_class)
       super(env)
 
       self.session = session
-      self.session_options = TestSession::DEFAULT_OPTIONS
+      self.session_options = TestSession::DEFAULT_OPTIONS.dup
+      @controller_class = controller_class
       @custom_param_parsers = {
-        xml: lambda { |raw_post| Hash.from_xml(raw_post)['hash'] }
+        xml: lambda { |raw_post| Hash.from_xml(raw_post)["hash"] }
       }
     end
 
@@ -61,7 +67,7 @@ module ActionController
     end
 
     def content_type=(type)
-      set_header 'CONTENT_TYPE', type
+      set_header "CONTENT_TYPE", type
     end
 
     def assign_parameters(routes, controller_path, action, parameters, generated_path, query_string_keys)
@@ -83,7 +89,7 @@ module ActionController
       end
 
       if get?
-        if self.query_string.blank?
+        if query_string.blank?
           self.query_string = non_path_parameters.to_query
         end
       else
@@ -91,8 +97,8 @@ module ActionController
           self.content_type = ENCODER.content_type
           data = ENCODER.build_multipart non_path_parameters
         else
-          fetch_header('CONTENT_TYPE') do |k|
-            set_header k, 'application/x-www-form-urlencoded'
+          fetch_header("CONTENT_TYPE") do |k|
+            set_header k, "application/x-www-form-urlencoded"
           end
 
           case content_mime_type.to_sym
@@ -110,8 +116,9 @@ module ActionController
           end
         end
 
-        set_header 'CONTENT_LENGTH', data.length.to_s
-        set_header 'rack.input', StringIO.new(data)
+        data_stream = StringIO.new(data)
+        set_header "CONTENT_LENGTH", data_stream.length.to_s
+        set_header "rack.input", data_stream
       end
 
       fetch_header("PATH_INFO") do |k|
@@ -127,7 +134,7 @@ module ActionController
       include Rack::Test::Utils
 
       def should_multipart?(params)
-        # FIXME: lifted from Rack-Test. We should push this separation upstream
+        # FIXME: lifted from Rack-Test. We should push this separation upstream.
         multipart = false
         query = lambda { |value|
           case value
@@ -152,9 +159,9 @@ module ActionController
 
     private
 
-    def params_parsers
-      super.merge @custom_param_parsers
-    end
+      def params_parsers
+        super.merge @custom_param_parsers
+      end
   end
 
   class LiveTestResponse < Live::Response
@@ -208,10 +215,18 @@ module ActionController
   end
 
   # Superclass for ActionController functional tests. Functional tests allow you to
-  # test a single controller action per test method. This should not be confused with
-  # integration tests (see ActionDispatch::IntegrationTest), which are more like
-  # "stories" that can involve multiple controllers and multiple actions (i.e. multiple
-  # different HTTP requests).
+  # test a single controller action per test method.
+  #
+  # == Use integration style controller tests over functional style controller tests.
+  #
+  # Rails discourages the use of functional tests in favor of integration tests
+  # (use ActionDispatch::IntegrationTest).
+  #
+  # New Rails applications no longer generate functional style controller tests and they should
+  # only be used for backward compatibility. Integration style controller tests perform actual
+  # requests, whereas functional style controller tests merely simulate a request. Besides,
+  # integration tests are as fast as functional tests and provide lot of helpers such as +as+,
+  # +parsed_body+ for effective testing of controller actions including even API endpoints.
   #
   # == Basic example
   #
@@ -288,7 +303,7 @@ module ActionController
   #   assert_equal "Dave", cookies[:name] # makes sure that a cookie called :name was set as "Dave"
   #   assert flash.empty? # makes sure that there's nothing in the flash
   #
-  # On top of the collections, you have the complete url that a given action redirected to available in <tt>redirect_to_url</tt>.
+  # On top of the collections, you have the complete URL that a given action redirected to available in <tt>redirect_to_url</tt>.
   #
   # For redirects within the same controller, you can even call follow_redirect and the redirect will be followed, triggering another
   # action call which can then be asserted against.
@@ -320,7 +335,6 @@ module ActionController
       attr_reader :response, :request
 
       module ClassMethods
-
         # Sets the controller class name. Useful if the name can't be inferred from test class.
         # Normalizes +controller_class+ before using.
         #
@@ -343,7 +357,7 @@ module ActionController
         end
 
         def controller_class
-          if current_controller_class = self._controller_class
+          if current_controller_class = _controller_class
             current_controller_class
           else
             self.controller_class = determine_default_controller_class(name)
@@ -377,56 +391,41 @@ module ActionController
       #
       # Note that the request method is not verified. The different methods are
       # available to make the tests more expressive.
-      def get(action, *args)
-        res = process_with_kwargs("GET", action, *args)
+      def get(action, **args)
+        res = process(action, method: "GET", **args)
         cookies.update res.cookies
         res
       end
 
       # Simulate a POST request with the given parameters and set/volley the response.
       # See +get+ for more details.
-      def post(action, *args)
-        process_with_kwargs("POST", action, *args)
+      def post(action, **args)
+        process(action, method: "POST", **args)
       end
 
       # Simulate a PATCH request with the given parameters and set/volley the response.
       # See +get+ for more details.
-      def patch(action, *args)
-        process_with_kwargs("PATCH", action, *args)
+      def patch(action, **args)
+        process(action, method: "PATCH", **args)
       end
 
       # Simulate a PUT request with the given parameters and set/volley the response.
       # See +get+ for more details.
-      def put(action, *args)
-        process_with_kwargs("PUT", action, *args)
+      def put(action, **args)
+        process(action, method: "PUT", **args)
       end
 
       # Simulate a DELETE request with the given parameters and set/volley the response.
       # See +get+ for more details.
-      def delete(action, *args)
-        process_with_kwargs("DELETE", action, *args)
+      def delete(action, **args)
+        process(action, method: "DELETE", **args)
       end
 
       # Simulate a HEAD request with the given parameters and set/volley the response.
       # See +get+ for more details.
-      def head(action, *args)
-        process_with_kwargs("HEAD", action, *args)
-      end
-
-      def xml_http_request(*args)
-        ActiveSupport::Deprecation.warn(<<-MSG.strip_heredoc)
-          xhr and xml_http_request methods are deprecated in favor of
-          `get :index, xhr: true` and `post :create, xhr: true`
-        MSG
-
-        @request.env['HTTP_X_REQUESTED_WITH'] = 'XMLHttpRequest'
-        @request.env['HTTP_ACCEPT'] ||= [Mime[:js], Mime[:html], Mime[:xml], 'text/xml', '*/*'].join(', ')
-        __send__(*args).tap do
-          @request.env.delete 'HTTP_X_REQUESTED_WITH'
-          @request.env.delete 'HTTP_ACCEPT'
-        end
+      def head(action, **args)
+        process(action, method: "HEAD", **args)
       end
-      alias xhr :xml_http_request
 
       # Simulate an HTTP request to +action+ by specifying request method,
       # parameters and set/volley the response.
@@ -440,6 +439,8 @@ module ActionController
       # - +session+: A hash of parameters to store in the session. This may be +nil+.
       # - +flash+: A hash of parameters to store in the flash. This may be +nil+.
       # - +format+: Request format. Defaults to +nil+. Can be string or symbol.
+      # - +as+: Content type. Defaults to +nil+. Must be a symbol that corresponds
+      #   to a mime type.
       #
       # Example calling +create+ action and sending two params:
       #
@@ -456,56 +457,39 @@ module ActionController
       # respectively which will make tests more expressive.
       #
       # Note that the request method is not verified.
-      def process(action, *args)
+      def process(action, method: "GET", params: {}, session: nil, body: nil, flash: {}, format: nil, xhr: false, as: nil)
         check_required_ivars
 
-        if kwarg_request?(args)
-          parameters, session, body, flash, http_method, format, xhr = args[0].values_at(:params, :session, :body, :flash, :method, :format, :xhr)
-        else
-          http_method, parameters, session, flash = args
-          format = nil
-
-          if parameters.is_a?(String) && http_method != 'HEAD'
-            body = parameters
-            parameters = nil
-          end
-
-          if parameters || session || flash
-            non_kwarg_request_warning
-          end
-        end
-
         if body
-          @request.set_header 'RAW_POST_DATA', body
-        end
-
-        if http_method
-          http_method = http_method.to_s.upcase
-        else
-          http_method = "GET"
+          @request.set_header "RAW_POST_DATA", body
         end
 
-        parameters ||= {}
-
-        if format
-          parameters[:format] = format
-        end
+        http_method = method.to_s.upcase
 
         @html_document = nil
 
-        self.cookies.update @request.cookies
-        self.cookies.update_cookies_from_jar
-        @request.set_header 'HTTP_COOKIE', cookies.to_header
-        @request.delete_header 'action_dispatch.cookies'
+        cookies.update(@request.cookies)
+        cookies.update_cookies_from_jar
+        @request.set_header "HTTP_COOKIE", cookies.to_header
+        @request.delete_header "action_dispatch.cookies"
 
-        @request          = TestRequest.new scrub_env!(@request.env), @request.session
+        @request          = TestRequest.new scrub_env!(@request.env), @request.session, @controller.class
         @response         = build_response @response_klass
         @response.request = @request
         @controller.recycle!
 
-        @request.set_header 'REQUEST_METHOD', http_method
+        @request.set_header "REQUEST_METHOD", http_method
 
-        parameters = parameters.symbolize_keys
+        if as
+          @request.content_type = Mime[as].to_s
+          format ||= as
+        end
+
+        parameters = params.symbolize_keys
+
+        if format
+          parameters[:format] = format
+        end
 
         generated_extras = @routes.generate_extras(parameters.merge(controller: controller_class_name, action: action.to_s))
         generated_path = generated_path(generated_extras)
@@ -517,9 +501,9 @@ module ActionController
         @request.flash.update(flash || {})
 
         if xhr
-          @request.set_header 'HTTP_X_REQUESTED_WITH', 'XMLHttpRequest'
-          @request.fetch_header('HTTP_ACCEPT') do |k|
-            @request.set_header k, [Mime[:js], Mime[:html], Mime[:xml], 'text/xml', '*/*'].join(', ')
+          @request.set_header "HTTP_X_REQUESTED_WITH", "XMLHttpRequest"
+          @request.fetch_header("HTTP_ACCEPT") do |k|
+            @request.set_header k, [Mime[:js], Mime[:html], Mime[:xml], "text/xml", "*/*"].join(", ")
           end
         end
 
@@ -534,27 +518,25 @@ module ActionController
           @request = @controller.request
           @response = @controller.response
 
-          @request.delete_header 'HTTP_COOKIE'
-
           if @request.have_cookie_jar?
             unless @request.cookie_jar.committed?
               @request.cookie_jar.write(@response)
-              self.cookies.update(@request.cookie_jar.instance_variable_get(:@cookies))
+              cookies.update(@request.cookie_jar.instance_variable_get(:@cookies))
             end
           end
           @response.prepare!
 
           if flash_value = @request.flash.to_session_value
-            @request.session['flash'] = flash_value
+            @request.session["flash"] = flash_value
           else
-            @request.session.delete('flash')
+            @request.session.delete("flash")
           end
 
           if xhr
-            @request.delete_header 'HTTP_X_REQUESTED_WITH'
-            @request.delete_header 'HTTP_ACCEPT'
+            @request.delete_header "HTTP_X_REQUESTED_WITH"
+            @request.delete_header "HTTP_ACCEPT"
           end
-          @request.query_string = ''
+          @request.query_string = ""
 
           @response.sent!
         end
@@ -592,7 +574,7 @@ module ActionController
           end
         end
 
-        @request          = TestRequest.create
+        @request          = TestRequest.create(@controller.class)
         @response         = build_response @response_klass
         @response.request = @request
 
@@ -611,71 +593,35 @@ module ActionController
         include ActionDispatch::Assertions
         class_attribute :_controller_class
         setup :setup_controller_request_and_response
+        ActiveSupport.run_load_hooks(:action_controller_test_case, self)
       end
 
       private
 
-      def scrub_env!(env)
-        env.delete_if { |k, v| k =~ /^(action_dispatch|rack)\.request/ }
-        env.delete_if { |k, v| k =~ /^action_dispatch\.rescue/ }
-        env.delete 'action_dispatch.request.query_parameters'
-        env.delete 'action_dispatch.request.request_parameters'
-        env
-      end
-
-      def process_with_kwargs(http_method, action, *args)
-        if kwarg_request?(args)
-          args.first.merge!(method: http_method)
-          process(action, *args)
-        else
-          non_kwarg_request_warning if args.any?
-
-          args = args.unshift(http_method)
-          process(action, *args)
+        def scrub_env!(env)
+          env.delete_if { |k, v| k =~ /^(action_dispatch|rack)\.request/ }
+          env.delete_if { |k, v| k =~ /^action_dispatch\.rescue/ }
+          env.delete "action_dispatch.request.query_parameters"
+          env.delete "action_dispatch.request.request_parameters"
+          env["rack.input"] = StringIO.new
+          env
         end
-      end
 
-      REQUEST_KWARGS = %i(params session flash method body xhr)
-      def kwarg_request?(args)
-        args[0].respond_to?(:keys) && (
-          (args[0].key?(:format) && args[0].keys.size == 1) ||
-          args[0].keys.any? { |k| REQUEST_KWARGS.include?(k) }
-        )
-      end
-
-      def non_kwarg_request_warning
-        ActiveSupport::Deprecation.warn(<<-MSG.strip_heredoc)
-          ActionController::TestCase HTTP request methods will accept only
-          keyword arguments in future Rails versions.
-
-          Examples:
-
-          get :show, params: { id: 1 }, session: { user_id: 1 }
-          process :update, method: :post, params: { id: 1 }
-        MSG
-      end
-
-      def document_root_element
-        html_document.root
-      end
+        def document_root_element
+          html_document.root
+        end
 
-      def check_required_ivars
-        # Sanity check for required instance variables so we can give an
-        # understandable error message.
-        [:@routes, :@controller, :@request, :@response].each do |iv_name|
-          if !instance_variable_defined?(iv_name) || instance_variable_get(iv_name).nil?
-            raise "#{iv_name} is nil: make sure you set it in your test's setup method."
+        def check_required_ivars
+          # Sanity check for required instance variables so we can give an
+          # understandable error message.
+          [:@routes, :@controller, :@request, :@response].each do |iv_name|
+            if !instance_variable_defined?(iv_name) || instance_variable_get(iv_name).nil?
+              raise "#{iv_name} is nil: make sure you set it in your test's setup method."
+            end
           end
         end
-      end
-
-      def html_format?(parameters)
-        return true unless parameters.key?(:format)
-        Mime.fetch(parameters[:format]) { Mime['html'] }.html?
-      end
     end
 
     include Behavior
   end
-  # :startdoc:
 end
diff --git a/actionpack/lib/action_dispatch.rb b/actionpack/lib/action_dispatch.rb
index 01d49475de..0822cdc0a6 100644
--- a/actionpack/lib/action_dispatch.rb
+++ b/actionpack/lib/action_dispatch.rb
@@ -1,5 +1,7 @@
+# frozen_string_literal: true
+
 #--
-# Copyright (c) 2004-2016 David Heinemeier Hansson
+# Copyright (c) 2004-2018 David Heinemeier Hansson
 #
 # Permission is hereby granted, free of charge, to any person obtaining
 # a copy of this software and associated documentation files (the
@@ -21,15 +23,15 @@
 # WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 #++
 
-require 'active_support'
-require 'active_support/rails'
-require 'active_support/core_ext/module/attribute_accessors'
+require "active_support"
+require "active_support/rails"
+require "active_support/core_ext/module/attribute_accessors"
 
-require 'action_pack'
-require 'rack'
+require "action_pack"
+require "rack"
 
 module Rack
-  autoload :Test, 'rack/test'
+  autoload :Test, "rack/test"
 end
 
 module ActionDispatch
@@ -39,21 +41,22 @@ module ActionDispatch
   end
 
   eager_autoload do
-    autoload_under 'http' do
+    autoload_under "http" do
+      autoload :ContentSecurityPolicy
       autoload :Request
       autoload :Response
     end
   end
 
-  autoload_under 'middleware' do
+  autoload_under "middleware" do
     autoload :RequestId
     autoload :Callbacks
     autoload :Cookies
     autoload :DebugExceptions
+    autoload :DebugLocks
     autoload :ExceptionWrapper
     autoload :Executor
     autoload :Flash
-    autoload :ParamsParser
     autoload :PublicExceptions
     autoload :Reloader
     autoload :RemoteIp
@@ -63,7 +66,7 @@ module ActionDispatch
   end
 
   autoload :Journey
-  autoload :MiddlewareStack, 'action_dispatch/middleware/stack'
+  autoload :MiddlewareStack, "action_dispatch/middleware/stack"
   autoload :Routing
 
   module Http
@@ -75,31 +78,33 @@ module ActionDispatch
     autoload :Parameters
     autoload :ParameterFilter
     autoload :Upload
-    autoload :UploadedFile, 'action_dispatch/http/upload'
+    autoload :UploadedFile, "action_dispatch/http/upload"
     autoload :URL
   end
 
   module Session
-    autoload :AbstractStore,     'action_dispatch/middleware/session/abstract_store'
-    autoload :CookieStore,       'action_dispatch/middleware/session/cookie_store'
-    autoload :MemCacheStore,     'action_dispatch/middleware/session/mem_cache_store'
-    autoload :CacheStore,        'action_dispatch/middleware/session/cache_store'
+    autoload :AbstractStore,     "action_dispatch/middleware/session/abstract_store"
+    autoload :CookieStore,       "action_dispatch/middleware/session/cookie_store"
+    autoload :MemCacheStore,     "action_dispatch/middleware/session/mem_cache_store"
+    autoload :CacheStore,        "action_dispatch/middleware/session/cache_store"
   end
 
   mattr_accessor :test_app
 
-  autoload_under 'testing' do
+  autoload_under "testing" do
     autoload :Assertions
     autoload :Integration
-    autoload :IntegrationTest, 'action_dispatch/testing/integration'
+    autoload :IntegrationTest, "action_dispatch/testing/integration"
     autoload :TestProcess
     autoload :TestRequest
     autoload :TestResponse
     autoload :AssertionResponse
   end
+
+  autoload :SystemTestCase, "action_dispatch/system_test_case"
 end
 
-autoload :Mime, 'action_dispatch/http/mime_type'
+autoload :Mime, "action_dispatch/http/mime_type"
 
 ActiveSupport.on_load(:action_view) do
   ActionView::Base.default_formats ||= Mime::SET.symbols
diff --git a/actionpack/lib/action_dispatch/http/cache.rb b/actionpack/lib/action_dispatch/http/cache.rb
index 9fa2e38ae3..a8febc32b3 100644
--- a/actionpack/lib/action_dispatch/http/cache.rb
+++ b/actionpack/lib/action_dispatch/http/cache.rb
@@ -1,10 +1,11 @@
+# frozen_string_literal: true
+
 module ActionDispatch
   module Http
     module Cache
       module Request
-
-        HTTP_IF_MODIFIED_SINCE = 'HTTP_IF_MODIFIED_SINCE'.freeze
-        HTTP_IF_NONE_MATCH     = 'HTTP_IF_NONE_MATCH'.freeze
+        HTTP_IF_MODIFIED_SINCE = "HTTP_IF_MODIFIED_SINCE".freeze
+        HTTP_IF_NONE_MATCH     = "HTTP_IF_NONE_MATCH".freeze
 
         def if_modified_since
           if since = get_header(HTTP_IF_MODIFIED_SINCE)
@@ -27,7 +28,7 @@ module ActionDispatch
         def etag_matches?(etag)
           if etag
             validators = if_none_match_etags
-            validators.include?(etag) || validators.include?('*')
+            validators.include?(etag) || validators.include?("*")
           end
         end
 
@@ -96,17 +97,17 @@ module ActionDispatch
         # support strong ETags and will ignore weak ETags entirely.
         #
         # Weak ETags are what we almost always need, so they're the default.
-        # Check out `#strong_etag=` to provide a strong ETag validator.
+        # Check out #strong_etag= to provide a strong ETag validator.
         def etag=(weak_validators)
           self.weak_etag = weak_validators
         end
 
         def weak_etag=(weak_validators)
-          set_header 'ETag', generate_weak_etag(weak_validators)
+          set_header "ETag", generate_weak_etag(weak_validators)
         end
 
         def strong_etag=(strong_validators)
-          set_header 'ETag', generate_strong_etag(strong_validators)
+          set_header "ETag", generate_strong_etag(strong_validators)
         end
 
         def etag?; etag; end
@@ -123,7 +124,7 @@ module ActionDispatch
 
       private
 
-        DATE          = 'Date'.freeze
+        DATE          = "Date".freeze
         LAST_MODIFIED = "Last-Modified".freeze
         SPECIAL_KEYS  = Set.new(%w[extras no-cache max-age public private must-revalidate])
 
@@ -132,12 +133,12 @@ module ActionDispatch
         end
 
         def generate_strong_etag(validators)
-          %("#{Digest::MD5.hexdigest(ActiveSupport::Cache.expand_cache_key(validators))}")
+          %("#{ActiveSupport::Digest.hexdigest(ActiveSupport::Cache.expand_cache_key(validators))}")
         end
 
         def cache_control_segments
           if cache_control = _cache_control
-            cache_control.delete(' ').split(',')
+            cache_control.delete(" ").split(",")
           else
             []
           end
@@ -147,10 +148,10 @@ module ActionDispatch
           cache_control = {}
 
           cache_control_segments.each do |segment|
-            directive, argument = segment.split('=', 2)
+            directive, argument = segment.split("=", 2)
 
             if SPECIAL_KEYS.include? directive
-              key = directive.tr('-', '_')
+              key = directive.tr("-", "_")
               cache_control[key.to_sym] = argument || true
             else
               cache_control[:extras] ||= []
@@ -165,19 +166,23 @@ module ActionDispatch
           @cache_control = cache_control_headers
         end
 
-        def handle_conditional_get!
-          if etag? || last_modified? || !@cache_control.empty?
-            set_conditional_cache_control!(@cache_control)
-          end
-        end
-
         DEFAULT_CACHE_CONTROL = "max-age=0, private, must-revalidate".freeze
         NO_CACHE              = "no-cache".freeze
         PUBLIC                = "public".freeze
         PRIVATE               = "private".freeze
         MUST_REVALIDATE       = "must-revalidate".freeze
 
-        def set_conditional_cache_control!(cache_control)
+        def handle_conditional_get!
+          # Normally default cache control setting is handled by ETag
+          # middleware. But, if an etag is already set, the middleware
+          # defaults to `no-cache` unless a default `Cache-Control` value is
+          # previously set. So, set a default one here.
+          if (etag? || last_modified?) && !self._cache_control
+            self._cache_control = DEFAULT_CACHE_CONTROL
+          end
+        end
+
+        def merge_and_normalize_cache_control!(cache_control)
           control = {}
           cc_headers = cache_control_headers
           if extras = cc_headers.delete(:extras)
@@ -190,7 +195,7 @@ module ActionDispatch
           control.merge! cache_control
 
           if control.empty?
-            self._cache_control = DEFAULT_CACHE_CONTROL
+            # Let middleware handle default behavior
           elsif control[:no_cache]
             self._cache_control = NO_CACHE
             if control[:extras]
diff --git a/actionpack/lib/action_dispatch/http/content_security_policy.rb b/actionpack/lib/action_dispatch/http/content_security_policy.rb
new file mode 100644
index 0000000000..4883e23d24
--- /dev/null
+++ b/actionpack/lib/action_dispatch/http/content_security_policy.rb
@@ -0,0 +1,231 @@
+# frozen_string_literal: true
+
+require "active_support/core_ext/object/deep_dup"
+
+module ActionDispatch #:nodoc:
+  class ContentSecurityPolicy
+    class Middleware
+      CONTENT_TYPE = "Content-Type".freeze
+      POLICY = "Content-Security-Policy".freeze
+      POLICY_REPORT_ONLY = "Content-Security-Policy-Report-Only".freeze
+
+      def initialize(app)
+        @app = app
+      end
+
+      def call(env)
+        request = ActionDispatch::Request.new env
+        _, headers, _ = response = @app.call(env)
+
+        return response unless html_response?(headers)
+        return response if policy_present?(headers)
+
+        if policy = request.content_security_policy
+          headers[header_name(request)] = policy.build(request.controller_instance)
+        end
+
+        response
+      end
+
+      private
+
+        def html_response?(headers)
+          if content_type = headers[CONTENT_TYPE]
+            content_type =~ /html/
+          end
+        end
+
+        def header_name(request)
+          if request.content_security_policy_report_only
+            POLICY_REPORT_ONLY
+          else
+            POLICY
+          end
+        end
+
+        def policy_present?(headers)
+          headers[POLICY] || headers[POLICY_REPORT_ONLY]
+        end
+    end
+
+    module Request
+      POLICY = "action_dispatch.content_security_policy".freeze
+      POLICY_REPORT_ONLY = "action_dispatch.content_security_policy_report_only".freeze
+
+      def content_security_policy
+        get_header(POLICY)
+      end
+
+      def content_security_policy=(policy)
+        set_header(POLICY, policy)
+      end
+
+      def content_security_policy_report_only
+        get_header(POLICY_REPORT_ONLY)
+      end
+
+      def content_security_policy_report_only=(value)
+        set_header(POLICY_REPORT_ONLY, value)
+      end
+    end
+
+    MAPPINGS = {
+      self:           "'self'",
+      unsafe_eval:    "'unsafe-eval'",
+      unsafe_inline:  "'unsafe-inline'",
+      none:           "'none'",
+      http:           "http:",
+      https:          "https:",
+      data:           "data:",
+      mediastream:    "mediastream:",
+      blob:           "blob:",
+      filesystem:     "filesystem:",
+      report_sample:  "'report-sample'",
+      strict_dynamic: "'strict-dynamic'"
+    }.freeze
+
+    DIRECTIVES = {
+      base_uri:        "base-uri",
+      child_src:       "child-src",
+      connect_src:     "connect-src",
+      default_src:     "default-src",
+      font_src:        "font-src",
+      form_action:     "form-action",
+      frame_ancestors: "frame-ancestors",
+      frame_src:       "frame-src",
+      img_src:         "img-src",
+      manifest_src:    "manifest-src",
+      media_src:       "media-src",
+      object_src:      "object-src",
+      script_src:      "script-src",
+      style_src:       "style-src",
+      worker_src:      "worker-src"
+    }.freeze
+
+    private_constant :MAPPINGS, :DIRECTIVES
+
+    attr_reader :directives
+
+    def initialize
+      @directives = {}
+      yield self if block_given?
+    end
+
+    def initialize_copy(other)
+      @directives = other.directives.deep_dup
+    end
+
+    DIRECTIVES.each do |name, directive|
+      define_method(name) do |*sources|
+        if sources.first
+          @directives[directive] = apply_mappings(sources)
+        else
+          @directives.delete(directive)
+        end
+      end
+    end
+
+    def block_all_mixed_content(enabled = true)
+      if enabled
+        @directives["block-all-mixed-content"] = true
+      else
+        @directives.delete("block-all-mixed-content")
+      end
+    end
+
+    def plugin_types(*types)
+      if types.first
+        @directives["plugin-types"] = types
+      else
+        @directives.delete("plugin-types")
+      end
+    end
+
+    def report_uri(uri)
+      @directives["report-uri"] = [uri]
+    end
+
+    def require_sri_for(*types)
+      if types.first
+        @directives["require-sri-for"] = types
+      else
+        @directives.delete("require-sri-for")
+      end
+    end
+
+    def sandbox(*values)
+      if values.empty?
+        @directives["sandbox"] = true
+      elsif values.first
+        @directives["sandbox"] = values
+      else
+        @directives.delete("sandbox")
+      end
+    end
+
+    def upgrade_insecure_requests(enabled = true)
+      if enabled
+        @directives["upgrade-insecure-requests"] = true
+      else
+        @directives.delete("upgrade-insecure-requests")
+      end
+    end
+
+    def build(context = nil)
+      build_directives(context).compact.join("; ") + ";"
+    end
+
+    private
+      def apply_mappings(sources)
+        sources.map do |source|
+          case source
+          when Symbol
+            apply_mapping(source)
+          when String, Proc
+            source
+          else
+            raise ArgumentError, "Invalid content security policy source: #{source.inspect}"
+          end
+        end
+      end
+
+      def apply_mapping(source)
+        MAPPINGS.fetch(source) do
+          raise ArgumentError, "Unknown content security policy source mapping: #{source.inspect}"
+        end
+      end
+
+      def build_directives(context)
+        @directives.map do |directive, sources|
+          if sources.is_a?(Array)
+            "#{directive} #{build_directive(sources, context).join(' ')}"
+          elsif sources
+            directive
+          else
+            nil
+          end
+        end
+      end
+
+      def build_directive(sources, context)
+        sources.map { |source| resolve_source(source, context) }
+      end
+
+      def resolve_source(source, context)
+        case source
+        when String
+          source
+        when Symbol
+          source.to_s
+        when Proc
+          if context.nil?
+            raise RuntimeError, "Missing context for the dynamic content security policy source: #{source.inspect}"
+          else
+            context.instance_exec(&source)
+          end
+        else
+          raise RuntimeError, "Unexpected content security policy source: #{source.inspect}"
+        end
+      end
+  end
+end
diff --git a/actionpack/lib/action_dispatch/http/filter_parameters.rb b/actionpack/lib/action_dispatch/http/filter_parameters.rb
index 041eca48ca..ec86b8bc47 100644
--- a/actionpack/lib/action_dispatch/http/filter_parameters.rb
+++ b/actionpack/lib/action_dispatch/http/filter_parameters.rb
@@ -1,4 +1,6 @@
-require 'action_dispatch/http/parameter_filter'
+# frozen_string_literal: true
+
+require "action_dispatch/http/parameter_filter"
 
 module ActionDispatch
   module Http
@@ -7,7 +9,7 @@ module ActionDispatch
     # sub-hashes of the params hash to filter. Filtering only certain sub-keys
     # from a hash is possible by using the dot notation: 'credit_card.number'.
     # If a block is given, each key and value of the params hash and all
-    # sub-hashes is passed to it, the value or key can be replaced using
+    # sub-hashes is passed to it, where the value or the key can be replaced using
     # String#replace or similar method.
     #
     #   env["action_dispatch.parameter_filter"] = [:password]
@@ -46,35 +48,35 @@ module ActionDispatch
         @filtered_env ||= env_filter.filter(@env)
       end
 
-      # Reconstructed a path with all sensitive GET parameters replaced.
+      # Reconstructs a path with all sensitive GET parameters replaced.
       def filtered_path
         @filtered_path ||= query_string.empty? ? path : "#{path}?#{filtered_query_string}"
       end
 
-    protected
+    private
 
-      def parameter_filter
+      def parameter_filter # :doc:
         parameter_filter_for fetch_header("action_dispatch.parameter_filter") {
           return NULL_PARAM_FILTER
         }
       end
 
-      def env_filter
+      def env_filter # :doc:
         user_key = fetch_header("action_dispatch.parameter_filter") {
           return NULL_ENV_FILTER
         }
         parameter_filter_for(Array(user_key) + ENV_MATCH)
       end
 
-      def parameter_filter_for(filters)
+      def parameter_filter_for(filters) # :doc:
         ParameterFilter.new(filters)
       end
 
-      KV_RE   = '[^&;=]+'
+      KV_RE   = "[^&;=]+"
       PAIR_RE = %r{(#{KV_RE})=(#{KV_RE})}
-      def filtered_query_string
+      def filtered_query_string # :doc:
         query_string.gsub(PAIR_RE) do |_|
-          parameter_filter.filter([[$1, $2]]).first.join("=")
+          parameter_filter.filter($1 => $2).first.join("=")
         end
       end
     end
diff --git a/actionpack/lib/action_dispatch/http/filter_redirect.rb b/actionpack/lib/action_dispatch/http/filter_redirect.rb
index f4b806b8b5..25394fe5dd 100644
--- a/actionpack/lib/action_dispatch/http/filter_redirect.rb
+++ b/actionpack/lib/action_dispatch/http/filter_redirect.rb
@@ -1,8 +1,9 @@
+# frozen_string_literal: true
+
 module ActionDispatch
   module Http
     module FilterRedirect
-
-      FILTERED = '[FILTERED]'.freeze # :nodoc:
+      FILTERED = "[FILTERED]".freeze # :nodoc:
 
       def filtered_location # :nodoc:
         if location_filter_match?
@@ -16,7 +17,7 @@ module ActionDispatch
 
       def location_filters
         if request
-          request.get_header('action_dispatch.redirect_filter') || []
+          request.get_header("action_dispatch.redirect_filter") || []
         else
           []
         end
@@ -31,7 +32,6 @@ module ActionDispatch
           end
         end
       end
-
     end
   end
 end
diff --git a/actionpack/lib/action_dispatch/http/headers.rb b/actionpack/lib/action_dispatch/http/headers.rb
index 69a934b7cd..c3c2a9d8c5 100644
--- a/actionpack/lib/action_dispatch/http/headers.rb
+++ b/actionpack/lib/action_dispatch/http/headers.rb
@@ -1,9 +1,11 @@
+# frozen_string_literal: true
+
 module ActionDispatch
   module Http
     # Provides access to the request's HTTP headers from the environment.
     #
     #   env     = { "CONTENT_TYPE" => "text/plain", "HTTP_USER_AGENT" => "curl/7.43.0" }
-    #   headers = ActionDispatch::Http::Headers.new(env)
+    #   headers = ActionDispatch::Http::Headers.from_hash(env)
     #   headers["Content-Type"] # => "text/plain"
     #   headers["User-Agent"] # => "curl/7.43.0"
     #
@@ -86,7 +88,7 @@ module ActionDispatch
         @req.fetch_header(env_name(key)) do
           return default unless default == DEFAULT
           return yield if block_given?
-          raise NameError, key
+          raise KeyError, key
         end
       end
 
@@ -115,16 +117,16 @@ module ActionDispatch
 
       private
 
-      # Converts an HTTP header name to an environment variable name if it is
-      # not contained within the headers hash.
-      def env_name(key)
-        key = key.to_s
-        if key =~ HTTP_HEADER
-          key = key.upcase.tr('-', '_')
-          key = "HTTP_" + key unless CGI_VARIABLES.include?(key)
+        # Converts an HTTP header name to an environment variable name if it is
+        # not contained within the headers hash.
+        def env_name(key)
+          key = key.to_s
+          if key =~ HTTP_HEADER
+            key = key.upcase.tr("-", "_")
+            key = "HTTP_" + key unless CGI_VARIABLES.include?(key)
+          end
+          key
         end
-        key
-      end
     end
   end
 end
diff --git a/actionpack/lib/action_dispatch/http/mime_negotiation.rb b/actionpack/lib/action_dispatch/http/mime_negotiation.rb
index 0a58ce2b96..d7435fa8df 100644
--- a/actionpack/lib/action_dispatch/http/mime_negotiation.rb
+++ b/actionpack/lib/action_dispatch/http/mime_negotiation.rb
@@ -1,4 +1,6 @@
-require 'active_support/core_ext/module/attribute_accessors'
+# frozen_string_literal: true
+
+require "active_support/core_ext/module/attribute_accessors"
 
 module ActionDispatch
   module Http
@@ -6,17 +8,13 @@ module ActionDispatch
       extend ActiveSupport::Concern
 
       included do
-        mattr_accessor :ignore_accept_header
-        self.ignore_accept_header = false
+        mattr_accessor :ignore_accept_header, default: false
       end
 
       # The MIME type of the HTTP request, such as Mime[:xml].
-      #
-      # For backward compatibility, the post \format is extracted from the
-      # X-Post-Data-Format HTTP header if present.
       def content_mime_type
         fetch_header("action_dispatch.request.content_type") do |k|
-          v = if get_header('CONTENT_TYPE') =~ /^([^,\;]*)/
+          v = if get_header("CONTENT_TYPE") =~ /^([^,\;]*)/
             Mime::Type.lookup($1.strip.downcase)
           else
             nil
@@ -29,14 +27,14 @@ module ActionDispatch
         content_mime_type && content_mime_type.to_s
       end
 
-      def has_content_type?
-        has_header? 'CONTENT_TYPE'
+      def has_content_type? # :nodoc:
+        get_header "CONTENT_TYPE"
       end
 
       # Returns the accepted MIME type for the request.
       def accepts
         fetch_header("action_dispatch.request.accepts") do |k|
-          header = get_header('HTTP_ACCEPT').to_s.strip
+          header = get_header("HTTP_ACCEPT").to_s.strip
 
           v = if header.empty?
             [content_mime_type]
@@ -135,9 +133,7 @@ module ActionDispatch
         }
       end
 
-      # Receives an array of mimes and return the first user sent mime that
-      # matches the order array.
-      #
+      # Returns the first MIME type that matches the provided array of MIME types.
       def negotiate_mime(order)
         formats.each do |priority|
           if priority == Mime::ALL
@@ -150,25 +146,25 @@ module ActionDispatch
         order.include?(Mime::ALL) ? format : nil
       end
 
-      protected
+      private
 
-      BROWSER_LIKE_ACCEPTS = /,\s*\*\/\*|\*\/\*\s*,/
+        BROWSER_LIKE_ACCEPTS = /,\s*\*\/\*|\*\/\*\s*,/
 
-      def valid_accept_header
-        (xhr? && (accept.present? || content_mime_type)) ||
-          (accept.present? && accept !~ BROWSER_LIKE_ACCEPTS)
-      end
+        def valid_accept_header # :doc:
+          (xhr? && (accept.present? || content_mime_type)) ||
+            (accept.present? && accept !~ BROWSER_LIKE_ACCEPTS)
+        end
 
-      def use_accept_header
-        !self.class.ignore_accept_header
-      end
+        def use_accept_header # :doc:
+          !self.class.ignore_accept_header
+        end
 
-      def format_from_path_extension
-        path = get_header('action_dispatch.original_path') || get_header('PATH_INFO')
-        if match = path && path.match(/\.(\w+)\z/)
-          Mime[match.captures.first]
+        def format_from_path_extension # :doc:
+          path = get_header("action_dispatch.original_path") || get_header("PATH_INFO")
+          if match = path && path.match(/\.(\w+)\z/)
+            Mime[match.captures.first]
+          end
         end
-      end
     end
   end
 end
diff --git a/actionpack/lib/action_dispatch/http/mime_type.rb b/actionpack/lib/action_dispatch/http/mime_type.rb
index 4672ea7199..d2b2106845 100644
--- a/actionpack/lib/action_dispatch/http/mime_type.rb
+++ b/actionpack/lib/action_dispatch/http/mime_type.rb
@@ -1,8 +1,9 @@
+# frozen_string_literal: true
+
 # -*- frozen-string-literal: true -*-
 
-require 'singleton'
-require 'active_support/core_ext/module/attribute_accessors'
-require 'active_support/core_ext/string/starts_ends_with'
+require "singleton"
+require "active_support/core_ext/string/starts_ends_with"
 
 module Mime
   class Mimes
@@ -45,35 +46,9 @@ module Mime
       return type if type.is_a?(Type)
       EXTENSION_LOOKUP.fetch(type.to_s) { |k| yield k }
     end
-
-    def const_missing(sym)
-      ext = sym.downcase
-      if Mime[ext]
-        ActiveSupport::Deprecation.warn(<<-MSG.squish)
-          Accessing mime types via constants is deprecated.
-          Please change `Mime::#{sym}` to `Mime[:#{ext}]`.
-        MSG
-        Mime[ext]
-      else
-        super
-      end
-    end
-
-    def const_defined?(sym, inherit = true)
-      ext = sym.downcase
-      if Mime[ext]
-        ActiveSupport::Deprecation.warn(<<-MSG.squish)
-          Accessing mime types via constants is deprecated.
-          Please change `Mime.const_defined?(#{sym})` to `Mime[:#{ext}]`.
-        MSG
-        true
-      else
-        super
-      end
-    end
   end
 
-  # Encapsulates the notion of a mime type. Can be used at render time, for example, with:
+  # Encapsulates the notion of a MIME type. Can be used at render time, for example, with:
   #
   #   class PostsController < ActionController::Base
   #     def show
@@ -91,7 +66,7 @@ module Mime
 
     @register_callbacks = []
 
-    # A simple helper class used in parsing the accept header
+    # A simple helper class used in parsing the accept header.
     class AcceptItem #:nodoc:
       attr_accessor :index, :name, :q
       alias :to_s :name
@@ -99,7 +74,7 @@ module Mime
       def initialize(index, name, q = nil)
         @index = index
         @name = name
-        q ||= 0.0 if @name == '*/*'.freeze # default wildcard match to end of list
+        q ||= 0.0 if @name == "*/*".freeze # Default wildcard match to end of list.
         @q = ((q || 1.0).to_f * 100).to_i
       end
 
@@ -114,25 +89,25 @@ module Mime
       def self.sort!(list)
         list.sort!
 
-        text_xml_idx = find_item_by_name list, 'text/xml'
+        text_xml_idx = find_item_by_name list, "text/xml"
         app_xml_idx = find_item_by_name list, Mime[:xml].to_s
 
-        # Take care of the broken text/xml entry by renaming or deleting it
+        # Take care of the broken text/xml entry by renaming or deleting it.
         if text_xml_idx && app_xml_idx
           app_xml = list[app_xml_idx]
           text_xml = list[text_xml_idx]
 
-          app_xml.q = [text_xml.q, app_xml.q].max # set the q value to the max of the two
-          if app_xml_idx > text_xml_idx  # make sure app_xml is ahead of text_xml in the list
+          app_xml.q = [text_xml.q, app_xml.q].max # Set the q value to the max of the two.
+          if app_xml_idx > text_xml_idx  # Make sure app_xml is ahead of text_xml in the list.
             list[app_xml_idx], list[text_xml_idx] = text_xml, app_xml
             app_xml_idx, text_xml_idx = text_xml_idx, app_xml_idx
           end
-          list.delete_at(text_xml_idx)                 # delete text_xml from the list
+          list.delete_at(text_xml_idx)  # Delete text_xml from the list.
         elsif text_xml_idx
           list[text_xml_idx].name = Mime[:xml].to_s
         end
 
-        # Look for more specific XML-based types and sort them ahead of app/xml
+        # Look for more specific XML-based types and sort them ahead of app/xml.
         if app_xml_idx
           app_xml = list[app_xml_idx]
           idx = app_xml_idx
@@ -141,7 +116,7 @@ module Mime
             type = list[idx]
             break if type.q < app_xml.q
 
-            if type.name.ends_with? '+xml'
+            if type.name.ends_with? "+xml"
               list[app_xml_idx], list[idx] = list[idx], app_xml
               app_xml_idx = idx
             end
@@ -174,7 +149,7 @@ module Mime
         EXTENSION_LOOKUP[extension.to_s]
       end
 
-      # Registers an alias that's not used on mime type lookup, but can be referenced directly. Especially useful for
+      # Registers an alias that's not used on MIME type lookup, but can be referenced directly. Especially useful for
       # rendering different HTML versions depending on the user agent, like an iPhone.
       def register_alias(string, symbol, extension_synonyms = [])
         register(string, symbol, [], extension_synonyms, true)
@@ -195,12 +170,12 @@ module Mime
       end
 
       def parse(accept_header)
-        if !accept_header.include?(',')
+        if !accept_header.include?(",")
           accept_header = accept_header.split(PARAMETER_SEPARATOR_REGEXP).first
           parse_trailing_star(accept_header) || [Mime::Type.lookup(accept_header)].compact
         else
           list, index = [], 0
-          accept_header.split(',').each do |header|
+          accept_header.split(",").each do |header|
             params, q = header.split(PARAMETER_SEPARATOR_REGEXP)
 
             next unless params
@@ -304,33 +279,35 @@ module Mime
 
     def all?; false; end
 
+    # TODO Change this to private once we've dropped Ruby 2.2 support.
+    # Workaround for Ruby 2.2 "private attribute?" warning.
     protected
 
-    attr_reader :string, :synonyms
+      attr_reader :string, :synonyms
 
     private
 
-    def to_ary; end
-    def to_a; end
+      def to_ary; end
+      def to_a; end
 
-    def method_missing(method, *args)
-      if method.to_s.ends_with? '?'
-        method[0..-2].downcase.to_sym == to_sym
-      else
-        super
+      def method_missing(method, *args)
+        if method.to_s.ends_with? "?"
+          method[0..-2].downcase.to_sym == to_sym
+        else
+          super
+        end
       end
-    end
 
-    def respond_to_missing?(method, include_private = false) #:nodoc:
-      method.to_s.ends_with? '?'
-    end
+      def respond_to_missing?(method, include_private = false)
+        (method.to_s.ends_with? "?") || super
+      end
   end
 
   class AllType < Type
     include Singleton
 
     def initialize
-      super '*/*', :all
+      super "*/*", :all
     end
 
     def all?; true; end
@@ -351,15 +328,15 @@ module Mime
 
     def ref; end
 
-    def respond_to_missing?(method, include_private = false)
-      method.to_s.ends_with? '?'
-    end
-
     private
-    def method_missing(method, *args)
-      false if method.to_s.ends_with? '?'
-    end
+      def respond_to_missing?(method, _)
+        method.to_s.ends_with? "?"
+      end
+
+      def method_missing(method, *args)
+        false if method.to_s.ends_with? "?"
+      end
   end
 end
 
-require 'action_dispatch/http/mime_types'
+require "action_dispatch/http/mime_types"
diff --git a/actionpack/lib/action_dispatch/http/mime_types.rb b/actionpack/lib/action_dispatch/http/mime_types.rb
index 8b04174f1f..342e6de312 100644
--- a/actionpack/lib/action_dispatch/http/mime_types.rb
+++ b/actionpack/lib/action_dispatch/http/mime_types.rb
@@ -1,5 +1,7 @@
+# frozen_string_literal: true
+
 # Build list of Mime types for HTTP responses
-# http://www.iana.org/assignments/media-types/
+# https://www.iana.org/assignments/media-types/
 
 Mime::Type.register "text/html", :html, %w( application/xhtml+xml ), %w( xhtml )
 Mime::Type.register "text/plain", :text, [], %w(txt)
@@ -8,6 +10,7 @@ Mime::Type.register "text/css", :css
 Mime::Type.register "text/calendar", :ics
 Mime::Type.register "text/csv", :csv
 Mime::Type.register "text/vcard", :vcf
+Mime::Type.register "text/vtt", :vtt, %w(vtt)
 
 Mime::Type.register "image/png", :png, [], %w(png)
 Mime::Type.register "image/jpeg", :jpeg, [], %w(jpg jpeg jpe pjpeg)
@@ -18,6 +21,18 @@ Mime::Type.register "image/svg+xml", :svg
 
 Mime::Type.register "video/mpeg", :mpeg, [], %w(mpg mpeg mpe)
 
+Mime::Type.register "audio/mpeg", :mp3, [], %w(mp1 mp2 mp3)
+Mime::Type.register "audio/ogg", :ogg, [], %w(oga ogg spx opus)
+Mime::Type.register "audio/aac", :m4a, %w( audio/mp4 ), %w(m4a mpg4 aac)
+
+Mime::Type.register "video/webm", :webm, [], %w(webm)
+Mime::Type.register "video/mp4", :mp4, [], %w(mp4 m4v)
+
+Mime::Type.register "font/otf", :otf, [], %w(otf)
+Mime::Type.register "font/ttf", :ttf, [], %w(ttf)
+Mime::Type.register "font/woff", :woff, [], %w(woff)
+Mime::Type.register "font/woff2", :woff2, [], %w(woff2)
+
 Mime::Type.register "application/xml", :xml, %w( text/xml application/x-xml )
 Mime::Type.register "application/rss+xml", :rss
 Mime::Type.register "application/atom+xml", :atom
@@ -26,7 +41,7 @@ Mime::Type.register "application/x-yaml", :yaml, %w( text/yaml ), %w(yml yaml)
 Mime::Type.register "multipart/form-data", :multipart_form
 Mime::Type.register "application/x-www-form-urlencoded", :url_encoded_form
 
-# http://www.ietf.org/rfc/rfc4627.txt
+# https://www.ietf.org/rfc/rfc4627.txt
 # http://www.json.org/JSONRequest.html
 Mime::Type.register "application/json", :json, %w( text/x-json application/jsonrequest )
 
diff --git a/actionpack/lib/action_dispatch/http/parameter_filter.rb b/actionpack/lib/action_dispatch/http/parameter_filter.rb
index e826551f4b..1d58964862 100644
--- a/actionpack/lib/action_dispatch/http/parameter_filter.rb
+++ b/actionpack/lib/action_dispatch/http/parameter_filter.rb
@@ -1,7 +1,11 @@
+# frozen_string_literal: true
+
+require "active_support/core_ext/object/duplicable"
+
 module ActionDispatch
   module Http
     class ParameterFilter
-      FILTERED = '[FILTERED]'.freeze # :nodoc:
+      FILTERED = "[FILTERED]".freeze # :nodoc:
 
       def initialize(filters = [])
         @filters = filters
@@ -37,8 +41,8 @@ module ActionDispatch
           deep_regexps, regexps = regexps.partition { |r| r.to_s.include?("\\.".freeze) }
           deep_strings, strings = strings.partition { |s| s.include?("\\.".freeze) }
 
-          regexps << Regexp.new(strings.join('|'.freeze), true) unless strings.empty?
-          deep_regexps << Regexp.new(deep_strings.join('|'.freeze), true) unless deep_strings.empty?
+          regexps << Regexp.new(strings.join("|".freeze), true) unless strings.empty?
+          deep_regexps << Regexp.new(deep_strings.join("|".freeze), true) unless deep_strings.empty?
 
           new regexps, deep_regexps, blocks
         end
@@ -48,17 +52,17 @@ module ActionDispatch
         def initialize(regexps, deep_regexps, blocks)
           @regexps = regexps
           @deep_regexps = deep_regexps.any? ? deep_regexps : nil
-          @blocks  = blocks
+          @blocks = blocks
         end
 
         def call(original_params, parents = [])
-          filtered_params = {}
+          filtered_params = original_params.class.new
 
           original_params.each do |key, value|
             parents.push(key) if deep_regexps
             if regexps.any? { |r| key =~ r }
               value = FILTERED
-            elsif deep_regexps && (joined = parents.join('.')) && deep_regexps.any? { |r| joined =~ r }
+            elsif deep_regexps && (joined = parents.join(".")) && deep_regexps.any? { |r| joined =~ r }
               value = FILTERED
             elsif value.is_a?(Hash)
               value = call(value, parents)
diff --git a/actionpack/lib/action_dispatch/http/parameters.rb b/actionpack/lib/action_dispatch/http/parameters.rb
index ff5031d7d5..8d7431fd6b 100644
--- a/actionpack/lib/action_dispatch/http/parameters.rb
+++ b/actionpack/lib/action_dispatch/http/parameters.rb
@@ -1,19 +1,30 @@
+# frozen_string_literal: true
+
 module ActionDispatch
   module Http
     module Parameters
       extend ActiveSupport::Concern
 
-      PARAMETERS_KEY = 'action_dispatch.request.path_parameters'
+      PARAMETERS_KEY = "action_dispatch.request.path_parameters"
 
       DEFAULT_PARSERS = {
         Mime[:json].symbol => -> (raw_post) {
           data = ActiveSupport::JSON.decode(raw_post)
-          data.is_a?(Hash) ? data : {:_json => data}
+          data.is_a?(Hash) ? data : { _json: data }
         }
       }
 
+      # Raised when raw data from the request cannot be parsed by the parser
+      # defined for request's content MIME type.
+      class ParseError < StandardError
+        def initialize
+          super($!.message)
+        end
+      end
+
       included do
         class << self
+          # Returns the parameter parsers.
           attr_reader :parameter_parsers
         end
 
@@ -21,7 +32,16 @@ module ActionDispatch
       end
 
       module ClassMethods
-        def parameter_parsers=(parsers) # :nodoc:
+        # Configure the parameter parser for a given MIME type.
+        #
+        # It accepts a hash where the key is the symbol of the MIME type
+        # and the value is a proc.
+        #
+        #     original_parsers = ActionDispatch::Request.parameter_parsers
+        #     xml_parser = -> (raw_post) { Hash.from_xml(raw_post) || {} }
+        #     new_parsers = original_parsers.merge(xml: xml_parser)
+        #     ActionDispatch::Request.parameter_parsers = new_parsers
+        def parameter_parsers=(parsers)
           @parameter_parsers = parsers.transform_keys { |key| key.respond_to?(:symbol) ? key.symbol : key }
         end
       end
@@ -37,14 +57,23 @@ module ActionDispatch
                    query_parameters.dup
                  end
         params.merge!(path_parameters)
+        params = set_binary_encoding(params, params[:controller], params[:action])
         set_header("action_dispatch.request.parameters", params)
         params
       end
       alias :params :parameters
 
       def path_parameters=(parameters) #:nodoc:
-        delete_header('action_dispatch.request.parameters')
+        delete_header("action_dispatch.request.parameters")
+
+        parameters = set_binary_encoding(parameters, parameters[:controller], parameters[:action])
+        # If any of the path parameters has an invalid encoding then
+        # raise since it's likely to trigger errors further on.
+        Request::Utils.check_param_encoding(parameters)
+
         set_header PARAMETERS_KEY, parameters
+      rescue Rack::Utils::ParameterTypeError, Rack::Utils::InvalidParameterError => e
+        raise ActionController::BadRequest.new("Invalid path parameters: #{e.message}")
       end
 
       # Returns a hash with the \parameters used to form the \path of the request.
@@ -57,24 +86,41 @@ module ActionDispatch
 
       private
 
-      def parse_formatted_parameters(parsers)
-        return yield if content_length.zero?
+        def set_binary_encoding(params, controller, action)
+          return params unless controller && controller.valid_encoding?
+
+          if binary_params_for?(controller, action)
+            ActionDispatch::Request::Utils.each_param_value(params) do |param|
+              param.force_encoding ::Encoding::ASCII_8BIT
+            end
+          end
+          params
+        end
+
+        def binary_params_for?(controller, action)
+          controller_class_for(controller).binary_params_for?(action)
+        rescue NameError
+          false
+        end
+
+        def parse_formatted_parameters(parsers)
+          return yield if content_length.zero? || content_mime_type.nil?
 
-        strategy = parsers.fetch(content_mime_type.symbol) { return yield }
+          strategy = parsers.fetch(content_mime_type.symbol) { return yield }
 
-        begin
-          strategy.call(raw_post)
-        rescue # JSON or Ruby code block errors
-          my_logger = logger || ActiveSupport::Logger.new($stderr)
-          my_logger.debug "Error occurred while parsing request parameters.\nContents:\n\n#{raw_post}"
+          begin
+            strategy.call(raw_post)
+          rescue # JSON or Ruby code block errors.
+            my_logger = logger || ActiveSupport::Logger.new($stderr)
+            my_logger.debug "Error occurred while parsing request parameters.\nContents:\n\n#{raw_post}"
 
-          raise ParamsParser::ParseError
+            raise ParseError
+          end
         end
-      end
 
-      def params_parsers
-        ActionDispatch::Request.parameter_parsers
-      end
+        def params_parsers
+          ActionDispatch::Request.parameter_parsers
+        end
     end
   end
 end
diff --git a/actionpack/lib/action_dispatch/http/rack_cache.rb b/actionpack/lib/action_dispatch/http/rack_cache.rb
index 003ae4029d..3e2d01aea3 100644
--- a/actionpack/lib/action_dispatch/http/rack_cache.rb
+++ b/actionpack/lib/action_dispatch/http/rack_cache.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require "rack/cache"
 require "rack/cache/context"
 require "active_support/cache"
diff --git a/actionpack/lib/action_dispatch/http/request.rb b/actionpack/lib/action_dispatch/http/request.rb
index b0ed681623..3838b84a7a 100644
--- a/actionpack/lib/action_dispatch/http/request.rb
+++ b/actionpack/lib/action_dispatch/http/request.rb
@@ -1,16 +1,18 @@
-require 'stringio'
-
-require 'active_support/inflector'
-require 'action_dispatch/http/headers'
-require 'action_controller/metal/exceptions'
-require 'rack/request'
-require 'action_dispatch/http/cache'
-require 'action_dispatch/http/mime_negotiation'
-require 'action_dispatch/http/parameters'
-require 'action_dispatch/http/filter_parameters'
-require 'action_dispatch/http/upload'
-require 'action_dispatch/http/url'
-require 'active_support/core_ext/array/conversions'
+# frozen_string_literal: true
+
+require "stringio"
+
+require "active_support/inflector"
+require "action_dispatch/http/headers"
+require "action_controller/metal/exceptions"
+require "rack/request"
+require "action_dispatch/http/cache"
+require "action_dispatch/http/mime_negotiation"
+require "action_dispatch/http/parameters"
+require "action_dispatch/http/filter_parameters"
+require "action_dispatch/http/upload"
+require "action_dispatch/http/url"
+require "active_support/core_ext/array/conversions"
 
 module ActionDispatch
   class Request
@@ -20,10 +22,11 @@ module ActionDispatch
     include ActionDispatch::Http::Parameters
     include ActionDispatch::Http::FilterParameters
     include ActionDispatch::Http::URL
+    include ActionDispatch::ContentSecurityPolicy::Request
     include Rack::Request::Env
 
-    autoload :Session, 'action_dispatch/request/session'
-    autoload :Utils,   'action_dispatch/request/utils'
+    autoload :Session, "action_dispatch/request/session"
+    autoload :Utils,   "action_dispatch/request/utils"
 
     LOCALHOST   = Regexp.union [/^127\.\d{1,3}\.\d{1,3}\.\d{1,3}$/, /^::1$/, /^0:0:0:0:0:0:0:1(%.*)?$/]
 
@@ -66,29 +69,21 @@ module ActionDispatch
     def commit_cookie_jar! # :nodoc:
     end
 
-    def check_path_parameters!
-      # If any of the path parameters has an invalid encoding then
-      # raise since it's likely to trigger errors further on.
-      path_parameters.each do |key, value|
-        next unless value.respond_to?(:valid_encoding?)
-        unless value.valid_encoding?
-          raise ActionController::BadRequest, "Invalid parameter encoding: #{key} => #{value.inspect}"
-        end
-      end
-    end
-
     PASS_NOT_FOUND = Class.new { # :nodoc:
       def self.action(_); self; end
-      def self.call(_); [404, {'X-Cascade' => 'pass'}, []]; end
+      def self.call(_); [404, { "X-Cascade" => "pass" }, []]; end
+      def self.binary_params_for?(action); false; end
     }
 
     def controller_class
-      check_path_parameters!
       params = path_parameters
+      params[:action] ||= "index"
+      controller_class_for(params[:controller])
+    end
 
-      if params.key?(:controller)
-        controller_param = params[:controller].underscore
-        params[:action] ||= 'index'
+    def controller_class_for(name)
+      if name
+        controller_param = name.underscore
         const_name = "#{controller_param.camelize}Controller"
         ActiveSupport::Dependencies.constantize(const_name)
       else
@@ -96,19 +91,22 @@ module ActionDispatch
       end
     end
 
+    # Returns true if the request has a header matching the given key parameter.
+    #
+    #    request.key? :ip_spoofing_check # => true
     def key?(key)
       has_header? key
     end
 
     # List of HTTP request methods from the following RFCs:
-    # Hypertext Transfer Protocol -- HTTP/1.1 (http://www.ietf.org/rfc/rfc2616.txt)
-    # HTTP Extensions for Distributed Authoring -- WEBDAV (http://www.ietf.org/rfc/rfc2518.txt)
-    # Versioning Extensions to WebDAV (http://www.ietf.org/rfc/rfc3253.txt)
-    # Ordered Collections Protocol (WebDAV) (http://www.ietf.org/rfc/rfc3648.txt)
-    # Web Distributed Authoring and Versioning (WebDAV) Access Control Protocol (http://www.ietf.org/rfc/rfc3744.txt)
-    # Web Distributed Authoring and Versioning (WebDAV) SEARCH (http://www.ietf.org/rfc/rfc5323.txt)
-    # Calendar Extensions to WebDAV (http://www.ietf.org/rfc/rfc4791.txt)
-    # PATCH Method for HTTP (http://www.ietf.org/rfc/rfc5789.txt)
+    # Hypertext Transfer Protocol -- HTTP/1.1 (https://www.ietf.org/rfc/rfc2616.txt)
+    # HTTP Extensions for Distributed Authoring -- WEBDAV (https://www.ietf.org/rfc/rfc2518.txt)
+    # Versioning Extensions to WebDAV (https://www.ietf.org/rfc/rfc3253.txt)
+    # Ordered Collections Protocol (WebDAV) (https://www.ietf.org/rfc/rfc3648.txt)
+    # Web Distributed Authoring and Versioning (WebDAV) Access Control Protocol (https://www.ietf.org/rfc/rfc3744.txt)
+    # Web Distributed Authoring and Versioning (WebDAV) SEARCH (https://www.ietf.org/rfc/rfc5323.txt)
+    # Calendar Extensions to WebDAV (https://www.ietf.org/rfc/rfc4791.txt)
+    # PATCH Method for HTTP (https://www.ietf.org/rfc/rfc5789.txt)
     RFC2616 = %w(OPTIONS GET HEAD POST PUT DELETE TRACE CONNECT)
     RFC2518 = %w(PROPFIND PROPPATCH MKCOL COPY MOVE LOCK UNLOCK)
     RFC3253 = %w(VERSION-CONTROL REPORT CHECKOUT CHECKIN UNCHECKOUT MKWORKSPACE UPDATE LABEL MERGE BASELINE-CONTROL MKACTIVITY)
@@ -122,7 +120,7 @@ module ActionDispatch
 
     HTTP_METHOD_LOOKUP = {}
 
-    # Populate the HTTP method lookup cache
+    # Populate the HTTP method lookup cache.
     HTTP_METHODS.each { |method|
       HTTP_METHOD_LOOKUP[method] = method.underscore.to_sym
     }
@@ -160,11 +158,11 @@ module ActionDispatch
     end
 
     def controller_instance # :nodoc:
-      get_header('action_controller.instance'.freeze)
+      get_header("action_controller.instance".freeze)
     end
 
     def controller_instance=(controller) # :nodoc:
-      set_header('action_controller.instance'.freeze, controller)
+      set_header("action_controller.instance".freeze, controller)
     end
 
     def http_auth_salt
@@ -173,12 +171,12 @@ module ActionDispatch
 
     def show_exceptions? # :nodoc:
       # We're treating `nil` as "unset", and we want the default setting to be
-      # `true`.  This logic should be extracted to `env_config` and calculated
+      # `true`. This logic should be extracted to `env_config` and calculated
       # once.
-      !(get_header('action_dispatch.show_exceptions'.freeze) == false)
+      !(get_header("action_dispatch.show_exceptions".freeze) == false)
     end
 
-    # Returns a symbol form of the #request_method
+    # Returns a symbol form of the #request_method.
     def request_method_symbol
       HTTP_METHOD_LOOKUP[request_method]
     end
@@ -187,10 +185,10 @@ module ActionDispatch
     # even if it was overridden by middleware. See #request_method for
     # more information.
     def method
-      @method ||= check_method(get_header("rack.methodoverride.original_method") || get_header('REQUEST_METHOD'))
+      @method ||= check_method(get_header("rack.methodoverride.original_method") || get_header("REQUEST_METHOD"))
     end
 
-    # Returns a symbol form of the #method
+    # Returns a symbol form of the #method.
     def method_symbol
       HTTP_METHOD_LOOKUP[method]
     end
@@ -202,6 +200,23 @@ module ActionDispatch
       @headers ||= Http::Headers.new(self)
     end
 
+    # Early Hints is an HTTP/2 status code that indicates hints to help a client start
+    # making preparations for processing the final response.
+    #
+    # If the env contains +rack.early_hints+ then the server accepts HTTP2 push for Link headers.
+    #
+    # The +send_early_hints+ method accepts a hash of links as follows:
+    #
+    #   send_early_hints("Link" => "</style.css>; rel=preload; as=style\n</script.js>; rel=preload")
+    #
+    # If you are using +javascript_include_tag+ or +stylesheet_link_tag+ the
+    # Early Hints headers are included by default if supported.
+    def send_early_hints(links)
+      return unless env["rack.early_hints"]
+
+      env["rack.early_hints"].call(links)
+    end
+
     # Returns a +String+ with the last requested path including their params.
     #
     #    # get '/foo'
@@ -249,7 +264,7 @@ module ActionDispatch
     # (case-insensitive), which may need to be manually added depending on the
     # choice of JavaScript libraries and frameworks.
     def xml_http_request?
-      get_header('HTTP_X_REQUESTED_WITH') =~ /XMLHttpRequest/i
+      get_header("HTTP_X_REQUESTED_WITH") =~ /XMLHttpRequest/i
     end
     alias :xhr? :xml_http_request?
 
@@ -275,7 +290,7 @@ module ActionDispatch
     # (which sets the action_dispatch.request_id environment variable).
     #
     # This unique ID is useful for tracing a request from end-to-end as part of logging or debugging.
-    # This relies on the rack variable set by the ActionDispatch::RequestId middleware.
+    # This relies on the Rack variable set by the ActionDispatch::RequestId middleware.
     def request_id
       get_header ACTION_DISPATCH_REQUEST_ID
     end
@@ -288,25 +303,25 @@ module ActionDispatch
 
     # Returns the lowercase name of the HTTP server software.
     def server_software
-      (get_header('SERVER_SOFTWARE') && /^([a-zA-Z]+)/ =~ get_header('SERVER_SOFTWARE')) ? $1.downcase : nil
+      (get_header("SERVER_SOFTWARE") && /^([a-zA-Z]+)/ =~ get_header("SERVER_SOFTWARE")) ? $1.downcase : nil
     end
 
     # Read the request \body. This is useful for web services that need to
     # work with raw requests directly.
     def raw_post
-      unless has_header? 'RAW_POST_DATA'
+      unless has_header? "RAW_POST_DATA"
         raw_post_body = body
-        set_header('RAW_POST_DATA', raw_post_body.read(content_length))
+        set_header("RAW_POST_DATA", raw_post_body.read(content_length))
         raw_post_body.rewind if raw_post_body.respond_to?(:rewind)
       end
-      get_header 'RAW_POST_DATA'
+      get_header "RAW_POST_DATA"
     end
 
     # The request body is an IO input stream. If the RAW_POST_DATA environment
     # variable is already set, wrap it in a StringIO.
     def body
-      if raw_post = get_header('RAW_POST_DATA')
-        raw_post.force_encoding(Encoding::BINARY)
+      if raw_post = get_header("RAW_POST_DATA")
+        raw_post = raw_post.dup.force_encoding(Encoding::BINARY)
         StringIO.new(raw_post)
       else
         body_stream
@@ -326,7 +341,7 @@ module ActionDispatch
     end
 
     def body_stream #:nodoc:
-      get_header('rack.input')
+      get_header("rack.input")
     end
 
     # TODO This should be broken apart into AD::Request::Session and probably
@@ -347,7 +362,7 @@ module ActionDispatch
       Session::Options.set self, options
     end
 
-    # Override Rack's GET method to support indifferent access
+    # Override Rack's GET method to support indifferent access.
     def GET
       fetch_header("action_dispatch.request.query_parameters") do |k|
         rack_query_params = super || {}
@@ -360,7 +375,7 @@ module ActionDispatch
     end
     alias :query_parameters :GET
 
-    # Override Rack's POST method to support indifferent access
+    # Override Rack's POST method to support indifferent access.
     def POST
       fetch_header("action_dispatch.request.request_parameters") do
         pr = parse_formatted_parameters(params_parsers) do |params|
@@ -368,7 +383,7 @@ module ActionDispatch
         end
         self.request_parameters = Request::Utils.normalize_encode_params(pr)
       end
-    rescue ParamsParser::ParseError # one of the parse strategies blew up
+    rescue Http::Parameters::ParseError # one of the parse strategies blew up
       self.request_parameters = Request::Utils.normalize_encode_params(super || {})
       raise
     rescue Rack::Utils::ParameterTypeError, Rack::Utils::InvalidParameterError => e
@@ -379,10 +394,10 @@ module ActionDispatch
     # Returns the authorization header regardless of whether it was specified directly or through one of the
     # proxy alternatives.
     def authorization
-      get_header('HTTP_AUTHORIZATION')   ||
-      get_header('X-HTTP_AUTHORIZATION') ||
-      get_header('X_HTTP_AUTHORIZATION') ||
-      get_header('REDIRECT_X_HTTP_AUTHORIZATION')
+      get_header("HTTP_AUTHORIZATION")   ||
+      get_header("X-HTTP_AUTHORIZATION") ||
+      get_header("X_HTTP_AUTHORIZATION") ||
+      get_header("REDIRECT_X_HTTP_AUTHORIZATION")
     end
 
     # True if the request came from localhost, 127.0.0.1, or ::1.
@@ -403,7 +418,7 @@ module ActionDispatch
     end
 
     def ssl?
-      super || scheme == 'wss'.freeze
+      super || scheme == "wss".freeze
     end
 
     private
diff --git a/actionpack/lib/action_dispatch/http/response.rb b/actionpack/lib/action_dispatch/http/response.rb
index 1515d59df3..7e50cb6d23 100644
--- a/actionpack/lib/action_dispatch/http/response.rb
+++ b/actionpack/lib/action_dispatch/http/response.rb
@@ -1,7 +1,9 @@
-require 'active_support/core_ext/module/attribute_accessors'
-require 'action_dispatch/http/filter_redirect'
-require 'action_dispatch/http/cache'
-require 'monitor'
+# frozen_string_literal: true
+
+require "active_support/core_ext/module/attribute_accessors"
+require "action_dispatch/http/filter_redirect"
+require "action_dispatch/http/cache"
+require "monitor"
 
 module ActionDispatch # :nodoc:
   # Represents an HTTP response generated by a controller action. Use it to
@@ -39,9 +41,9 @@ module ActionDispatch # :nodoc:
         super(header)
       end
 
-      def []=(k,v)
+      def []=(k, v)
         if @response.sending? || @response.sent?
-          raise ActionDispatch::IllegalStateError, 'header already sent'
+          raise ActionDispatch::IllegalStateError, "header already sent"
         end
 
         super
@@ -67,7 +69,7 @@ module ActionDispatch # :nodoc:
 
     alias_method :headers,  :header
 
-    delegate :[], :[]=, :to => :@header
+    delegate :[], :[]=, to: :@header
 
     def each(&block)
       sending!
@@ -81,11 +83,11 @@ module ActionDispatch # :nodoc:
     LOCATION     = "Location".freeze
     NO_CONTENT_CODES = [100, 101, 102, 204, 205, 304]
 
-    cattr_accessor(:default_charset) { "utf-8" }
-    cattr_accessor(:default_headers)
+    cattr_accessor :default_charset, default: "utf-8"
+    cattr_accessor :default_headers
 
     include Rack::Response::Helpers
-    # Aliasing these off because AD::Http::Cache::Response defines them
+    # Aliasing these off because AD::Http::Cache::Response defines them.
     alias :_cache_control :cache_control
     alias :_cache_control= :cache_control=
 
@@ -103,8 +105,8 @@ module ActionDispatch # :nodoc:
 
       def body
         @str_body ||= begin
-          buf = ''
-            each { |chunk| buf << chunk }
+          buf = "".dup
+          each { |chunk| buf << chunk }
           buf
         end
       end
@@ -142,7 +144,7 @@ module ActionDispatch # :nodoc:
       private
 
         def each_chunk(&block)
-          @buf.each(&block) # extract into own method
+          @buf.each(&block)
         end
     end
 
@@ -224,8 +226,12 @@ module ActionDispatch # :nodoc:
 
     # Sets the HTTP content type.
     def content_type=(content_type)
-      header_info = parse_content_type
-      set_content_type content_type.to_s, header_info.charset || self.class.default_charset
+      return unless content_type
+      new_header_info = parse_content_type(content_type.to_s)
+      prev_header_info = parsed_content_type_header
+      charset = new_header_info.charset || prev_header_info.charset
+      charset ||= self.class.default_charset unless prev_header_info.mime_type
+      set_content_type new_header_info.mime_type, charset
     end
 
     # Sets the HTTP response's content MIME type. For example, in the controller
@@ -238,7 +244,7 @@ module ActionDispatch # :nodoc:
     # information.
 
     def content_type
-      parse_content_type.mime_type
+      parsed_content_type_header.mime_type
     end
 
     def sending_file=(v)
@@ -247,17 +253,16 @@ module ActionDispatch # :nodoc:
       end
     end
 
-    # Sets the HTTP character set. In case of nil parameter
-    # it sets the charset to utf-8.
+    # Sets the HTTP character set. In case of +nil+ parameter
+    # it sets the charset to +default_charset+.
     #
     #   response.charset = 'utf-16' # => 'utf-16'
     #   response.charset = nil      # => 'utf-8'
     def charset=(charset)
-      header_info = parse_content_type
+      content_type = parsed_content_type_header.mime_type
       if false == charset
-        set_header CONTENT_TYPE, header_info.mime_type
+        set_content_type content_type, nil
       else
-        content_type = header_info.mime_type
         set_content_type content_type, charset || self.class.default_charset
       end
     end
@@ -265,7 +270,7 @@ module ActionDispatch # :nodoc:
     # The charset of the response. HTML wants to know the encoding of the
     # content you're giving them, so we need to send that along.
     def charset
-      header_info = parse_content_type
+      header_info = parsed_content_type_header
       header_info.charset || self.class.default_charset
     end
 
@@ -329,7 +334,7 @@ module ActionDispatch # :nodoc:
 
       # Stream the file's contents if Rack::Sendfile isn't present.
       def each
-        File.open(to_path, 'rb') do |file|
+        File.open(to_path, "rb") do |file|
           while chunk = file.read(16384)
             yield chunk
           end
@@ -389,7 +394,7 @@ module ActionDispatch # :nodoc:
       if header = get_header(SET_COOKIE)
         header = header.split("\n") if header.respond_to?(:to_str)
         header.each do |cookie|
-          if pair = cookie.split(';').first
+          if pair = cookie.split(";").first
             key, value = pair.split("=").map { |v| Rack::Utils.unescape(v) }
             cookies[key] = value
           end
@@ -403,26 +408,32 @@ module ActionDispatch # :nodoc:
     ContentTypeHeader = Struct.new :mime_type, :charset
     NullContentTypeHeader = ContentTypeHeader.new nil, nil
 
-    def parse_content_type
-      content_type = get_header CONTENT_TYPE
+    def parse_content_type(content_type)
       if content_type
         type, charset = content_type.split(/;\s*charset=/)
-        type = nil if type.empty?
+        type = nil if type && type.empty?
         ContentTypeHeader.new(type, charset)
       else
         NullContentTypeHeader
       end
     end
 
+    # Small internal convenience method to get the parsed version of the current
+    # content type header.
+    def parsed_content_type_header
+      parse_content_type(get_header(CONTENT_TYPE))
+    end
+
     def set_content_type(content_type, charset)
-      type = (content_type || '').dup
-      type << "; charset=#{charset}" if charset
+      type = (content_type || "").dup
+      type << "; charset=#{charset.to_s.downcase}" if charset
       set_header CONTENT_TYPE, type
     end
 
     def before_committed
       return if committed?
       assign_default_content_type_and_charset!
+      merge_and_normalize_cache_control!(@cache_control)
       handle_conditional_get!
       handle_no_content!
     end
@@ -450,7 +461,7 @@ module ActionDispatch # :nodoc:
     def assign_default_content_type_and_charset!
       return if content_type
 
-      ct = parse_content_type
+      ct = parsed_content_type_header
       set_content_type(ct.mime_type || Mime[:html].to_s,
                        ct.charset || self.class.default_charset)
     end
@@ -475,7 +486,7 @@ module ActionDispatch # :nodoc:
       end
 
       def respond_to?(method, include_private = false)
-        if method.to_s == 'to_path'
+        if method.to_s == "to_path"
           @response.stream.respond_to?(method)
         else
           super
@@ -494,7 +505,7 @@ module ActionDispatch # :nodoc:
     def handle_no_content!
       if NO_CONTENT_CODES.include?(@status)
         @header.delete CONTENT_TYPE
-        @header.delete 'Content-Length'
+        @header.delete "Content-Length"
       end
     end
 
diff --git a/actionpack/lib/action_dispatch/http/upload.rb b/actionpack/lib/action_dispatch/http/upload.rb
index a221f4c5af..0b162dc7f1 100644
--- a/actionpack/lib/action_dispatch/http/upload.rb
+++ b/actionpack/lib/action_dispatch/http/upload.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActionDispatch
   module Http
     # Models uploaded files.
@@ -24,23 +26,27 @@ module ActionDispatch
       attr_accessor :headers
 
       def initialize(hash) # :nodoc:
-        @tempfile          = hash[:tempfile]
-        raise(ArgumentError, ':tempfile is required') unless @tempfile
+        @tempfile = hash[:tempfile]
+        raise(ArgumentError, ":tempfile is required") unless @tempfile
+
+        if hash[:filename]
+          @original_filename = hash[:filename].dup
 
-        @original_filename = hash[:filename]
-        if @original_filename
           begin
             @original_filename.encode!(Encoding::UTF_8)
           rescue EncodingError
             @original_filename.force_encoding(Encoding::UTF_8)
           end
+        else
+          @original_filename = nil
         end
+
         @content_type      = hash[:type]
         @headers           = hash[:head]
       end
 
       # Shortcut for +tempfile.read+.
-      def read(length=nil, buffer=nil)
+      def read(length = nil, buffer = nil)
         @tempfile.read(length, buffer)
       end
 
@@ -50,7 +56,7 @@ module ActionDispatch
       end
 
       # Shortcut for +tempfile.close+.
-      def close(unlink_now=false)
+      def close(unlink_now = false)
         @tempfile.close(unlink_now)
       end
 
diff --git a/actionpack/lib/action_dispatch/http/url.rb b/actionpack/lib/action_dispatch/http/url.rb
index 7a1350a46d..f0344fd927 100644
--- a/actionpack/lib/action_dispatch/http/url.rb
+++ b/actionpack/lib/action_dispatch/http/url.rb
@@ -1,4 +1,6 @@
-require 'active_support/core_ext/module/attribute_accessors'
+# frozen_string_literal: true
+
+require "active_support/core_ext/module/attribute_accessors"
 
 module ActionDispatch
   module Http
@@ -7,8 +9,7 @@ module ActionDispatch
       HOST_REGEXP     = /(^[^:]+:\/\/)?(\[[^\]]+\]|[^:]+)(?::(\d+$))?/
       PROTOCOL_REGEXP = /^([^:]+)(:)?(\/\/)?$/
 
-      mattr_accessor :tld_length
-      self.tld_length = 1
+      mattr_accessor :tld_length, default: 1
 
       class << self
         # Returns the domain part of a host given the domain level.
@@ -42,7 +43,7 @@ module ActionDispatch
         #    # Second-level domain example
         #    extract_subdomain('dev.www.example.co.uk', 2) # => "dev.www"
         def extract_subdomain(host, tld_length)
-          extract_subdomains(host, tld_length).join('.')
+          extract_subdomains(host, tld_length).join(".")
         end
 
         def url_for(options)
@@ -59,14 +60,14 @@ module ActionDispatch
           port     = options[:port]
 
           unless host
-            raise ArgumentError, 'Missing host to link to! Please provide the :host parameter, set default_url_options[:host], or set :only_path to true'
+            raise ArgumentError, "Missing host to link to! Please provide the :host parameter, set default_url_options[:host], or set :only_path to true"
           end
 
           build_host_url(host, port, protocol, options, path_for(options))
         end
 
         def path_for(options)
-          path  = options[:script_name].to_s.chomp("/".freeze)
+          path = options[:script_name].to_s.chomp("/".freeze)
           path << options[:path] if options.key?(:path)
 
           add_trailing_slash(path) if options[:trailing_slash]
@@ -80,7 +81,7 @@ module ActionDispatch
 
         def add_params(path, params)
           params = { params: params } unless params.is_a?(Hash)
-          params.reject! { |_,v| v.to_param.nil? }
+          params.reject! { |_, v| v.to_param.nil? }
           query = params.to_query
           path << "?#{query}" unless query.empty?
         end
@@ -92,19 +93,17 @@ module ActionDispatch
         end
 
         def extract_domain_from(host, tld_length)
-          host.split('.').last(1 + tld_length).join('.')
+          host.split(".").last(1 + tld_length).join(".")
         end
 
         def extract_subdomains_from(host, tld_length)
-          parts = host.split('.')
+          parts = host.split(".")
           parts[0..-(tld_length + 2)]
         end
 
         def add_trailing_slash(path)
-          # includes querysting
-          if path.include?('?')
+          if path.include?("?")
             path.sub!(/\?/, '/\&')
-          # does not have a .format
           elsif !path.include?(".")
             path.sub!(/[^\/]\z|\A\z/, '\&/')
           end
@@ -158,11 +157,11 @@ module ActionDispatch
           subdomain  = options.fetch :subdomain, true
           domain     = options[:domain]
 
-          host = ""
+          host = "".dup
           if subdomain == true
             return _host if domain.nil?
 
-            host << extract_subdomains_from(_host, tld_length).join('.')
+            host << extract_subdomains_from(_host, tld_length).join(".")
           elsif subdomain
             host << subdomain.to_param
           end
@@ -192,11 +191,7 @@ module ActionDispatch
 
       # Returns the complete URL used for this request.
       #
-      #   class Request < Rack::Request
-      #     include ActionDispatch::Http::URL
-      #   end
-      #
-      #   req = Request.new 'HTTP_HOST' => 'example.com'
+      #   req = ActionDispatch::Request.new 'HTTP_HOST' => 'example.com'
       #   req.url # => "http://example.com"
       def url
         protocol + host_with_port + fullpath
@@ -204,68 +199,52 @@ module ActionDispatch
 
       # Returns 'https://' if this is an SSL request and 'http://' otherwise.
       #
-      #   class Request < Rack::Request
-      #     include ActionDispatch::Http::URL
-      #   end
-      #
-      #   req = Request.new 'HTTP_HOST' => 'example.com'
+      #   req = ActionDispatch::Request.new 'HTTP_HOST' => 'example.com'
       #   req.protocol # => "http://"
       #
-      #   req = Request.new 'HTTP_HOST' => 'example.com', 'HTTPS' => 'on'
+      #   req = ActionDispatch::Request.new 'HTTP_HOST' => 'example.com', 'HTTPS' => 'on'
       #   req.protocol # => "https://"
       def protocol
-        @protocol ||= ssl? ? 'https://' : 'http://'
+        @protocol ||= ssl? ? "https://" : "http://"
       end
 
       # Returns the \host and port for this request, such as "example.com:8080".
       #
-      #   class Request < Rack::Request
-      #     include ActionDispatch::Http::URL
-      #   end
-      #
-      #   req = Request.new 'HTTP_HOST' => 'example.com'
+      #   req = ActionDispatch::Request.new 'HTTP_HOST' => 'example.com'
       #   req.raw_host_with_port # => "example.com"
       #
-      #   req = Request.new 'HTTP_HOST' => 'example.com:80'
+      #   req = ActionDispatch::Request.new 'HTTP_HOST' => 'example.com:80'
       #   req.raw_host_with_port # => "example.com:80"
       #
-      #   req = Request.new 'HTTP_HOST' => 'example.com:8080'
+      #   req = ActionDispatch::Request.new 'HTTP_HOST' => 'example.com:8080'
       #   req.raw_host_with_port # => "example.com:8080"
       def raw_host_with_port
         if forwarded = x_forwarded_host.presence
           forwarded.split(/,\s?/).last
         else
-          get_header('HTTP_HOST') || "#{server_name || server_addr}:#{get_header('SERVER_PORT')}"
+          get_header("HTTP_HOST") || "#{server_name || server_addr}:#{get_header('SERVER_PORT')}"
         end
       end
 
       # Returns the host for this request, such as "example.com".
       #
-      #   class Request < Rack::Request
-      #     include ActionDispatch::Http::URL
-      #   end
-      #
-      #   req = Request.new 'HTTP_HOST' => 'example.com:8080'
+      #   req = ActionDispatch::Request.new 'HTTP_HOST' => 'example.com:8080'
       #   req.host # => "example.com"
       def host
-        raw_host_with_port.sub(/:\d+$/, ''.freeze)
+        raw_host_with_port.sub(/:\d+$/, "".freeze)
       end
 
       # Returns a \host:\port string for this request, such as "example.com" or
       # "example.com:8080". Port is only included if it is not a default port
       # (80 or 443)
       #
-      #   class Request < Rack::Request
-      #     include ActionDispatch::Http::URL
-      #   end
-      #
-      #   req = Request.new 'HTTP_HOST' => 'example.com'
+      #   req = ActionDispatch::Request.new 'HTTP_HOST' => 'example.com'
       #   req.host_with_port # => "example.com"
       #
-      #   req = Request.new 'HTTP_HOST' => 'example.com:80'
+      #   req = ActionDispatch::Request.new 'HTTP_HOST' => 'example.com:80'
       #   req.host_with_port # => "example.com"
       #
-      #   req = Request.new 'HTTP_HOST' => 'example.com:8080'
+      #   req = ActionDispatch::Request.new 'HTTP_HOST' => 'example.com:8080'
       #   req.host_with_port # => "example.com:8080"
       def host_with_port
         "#{host}#{port_string}"
@@ -273,14 +252,10 @@ module ActionDispatch
 
       # Returns the port number of this request as an integer.
       #
-      #   class Request < Rack::Request
-      #     include ActionDispatch::Http::URL
-      #   end
-      #
-      #   req = Request.new 'HTTP_HOST' => 'example.com'
+      #   req = ActionDispatch::Request.new 'HTTP_HOST' => 'example.com'
       #   req.port # => 80
       #
-      #   req = Request.new 'HTTP_HOST' => 'example.com:8080'
+      #   req = ActionDispatch::Request.new 'HTTP_HOST' => 'example.com:8080'
       #   req.port # => 8080
       def port
         @port ||= begin
@@ -294,29 +269,21 @@ module ActionDispatch
 
       # Returns the standard \port number for this request's protocol.
       #
-      #   class Request < Rack::Request
-      #     include ActionDispatch::Http::URL
-      #   end
-      #
-      #   req = Request.new 'HTTP_HOST' => 'example.com:8080'
+      #   req = ActionDispatch::Request.new 'HTTP_HOST' => 'example.com:8080'
       #   req.standard_port # => 80
       def standard_port
         case protocol
-          when 'https://' then 443
+        when "https://" then 443
           else 80
         end
       end
 
       # Returns whether this request is using the standard port
       #
-      #   class Request < Rack::Request
-      #     include ActionDispatch::Http::URL
-      #   end
-      #
-      #   req = Request.new 'HTTP_HOST' => 'example.com:80'
+      #   req = ActionDispatch::Request.new 'HTTP_HOST' => 'example.com:80'
       #   req.standard_port? # => true
       #
-      #   req = Request.new 'HTTP_HOST' => 'example.com:8080'
+      #   req = ActionDispatch::Request.new 'HTTP_HOST' => 'example.com:8080'
       #   req.standard_port? # => false
       def standard_port?
         port == standard_port
@@ -325,14 +292,10 @@ module ActionDispatch
       # Returns a number \port suffix like 8080 if the \port number of this request
       # is not the default HTTP \port 80 or HTTPS \port 443.
       #
-      #   class Request < Rack::Request
-      #     include ActionDispatch::Http::URL
-      #   end
-      #
-      #   req = Request.new 'HTTP_HOST' => 'example.com:80'
+      #   req = ActionDispatch::Request.new 'HTTP_HOST' => 'example.com:80'
       #   req.optional_port # => nil
       #
-      #   req = Request.new 'HTTP_HOST' => 'example.com:8080'
+      #   req = ActionDispatch::Request.new 'HTTP_HOST' => 'example.com:8080'
       #   req.optional_port # => 8080
       def optional_port
         standard_port? ? nil : port
@@ -341,32 +304,24 @@ module ActionDispatch
       # Returns a string \port suffix, including colon, like ":8080" if the \port
       # number of this request is not the default HTTP \port 80 or HTTPS \port 443.
       #
-      #   class Request < Rack::Request
-      #     include ActionDispatch::Http::URL
-      #   end
-      #
-      #   req = Request.new 'HTTP_HOST' => 'example.com:80'
+      #   req = ActionDispatch::Request.new 'HTTP_HOST' => 'example.com:80'
       #   req.port_string # => ""
       #
-      #   req = Request.new 'HTTP_HOST' => 'example.com:8080'
+      #   req = ActionDispatch::Request.new 'HTTP_HOST' => 'example.com:8080'
       #   req.port_string # => ":8080"
       def port_string
-        standard_port? ? '' : ":#{port}"
+        standard_port? ? "" : ":#{port}"
       end
 
       # Returns the requested port, such as 8080, based on SERVER_PORT
       #
-      #   class Request < Rack::Request
-      #     include ActionDispatch::Http::URL
-      #   end
-      #
-      #   req = Request.new 'SERVER_PORT' => '80'
+      #   req = ActionDispatch::Request.new 'SERVER_PORT' => '80'
       #   req.server_port # => 80
       #
-      #   req = Request.new 'SERVER_PORT' => '8080'
+      #   req = ActionDispatch::Request.new 'SERVER_PORT' => '8080'
       #   req.server_port # => 8080
       def server_port
-        get_header('SERVER_PORT').to_i
+        get_header("SERVER_PORT").to_i
       end
 
       # Returns the \domain part of a \host, such as "rubyonrails.org" in "www.rubyonrails.org". You can specify
diff --git a/actionpack/lib/action_dispatch/journey.rb b/actionpack/lib/action_dispatch/journey.rb
index ad42713482..2852efa6ae 100644
--- a/actionpack/lib/action_dispatch/journey.rb
+++ b/actionpack/lib/action_dispatch/journey.rb
@@ -1,5 +1,7 @@
-require 'action_dispatch/journey/router'
-require 'action_dispatch/journey/gtg/builder'
-require 'action_dispatch/journey/gtg/simulator'
-require 'action_dispatch/journey/nfa/builder'
-require 'action_dispatch/journey/nfa/simulator'
+# frozen_string_literal: true
+
+require "action_dispatch/journey/router"
+require "action_dispatch/journey/gtg/builder"
+require "action_dispatch/journey/gtg/simulator"
+require "action_dispatch/journey/nfa/builder"
+require "action_dispatch/journey/nfa/simulator"
diff --git a/actionpack/lib/action_dispatch/journey/formatter.rb b/actionpack/lib/action_dispatch/journey/formatter.rb
index 200477b002..0f04839d9b 100644
--- a/actionpack/lib/action_dispatch/journey/formatter.rb
+++ b/actionpack/lib/action_dispatch/journey/formatter.rb
@@ -1,10 +1,13 @@
-require 'action_controller/metal/exceptions'
+# frozen_string_literal: true
+
+require "action_controller/metal/exceptions"
 
 module ActionDispatch
+  # :stopdoc:
   module Journey
     # The Formatter class is used for formatting URLs. For example, parameters
     # passed to +url_for+ in Rails will eventually call Formatter#generate.
-    class Formatter # :nodoc:
+    class Formatter
       attr_reader :routes
 
       def initialize(routes)
@@ -14,7 +17,7 @@ module ActionDispatch
 
       def generate(name, options, path_parameters, parameterize = nil)
         constraints = path_parameters.merge(options)
-        missing_keys = nil # need for variable scope
+        missing_keys = nil
 
         match_route(name, constraints) do |route|
           parameterized_parts = extract_parameterized_parts(route, options, path_parameters, parameterize)
@@ -35,7 +38,7 @@ module ActionDispatch
 
           route.parts.reverse_each do |key|
             break if defaults[key].nil? && parameterized_parts[key].present?
-            break if parameterized_parts[key].to_s != defaults[key].to_s
+            next if parameterized_parts[key].to_s != defaults[key].to_s
             break if required_parts.include?(key)
 
             parameterized_parts.delete(key)
@@ -44,8 +47,12 @@ module ActionDispatch
           return [route.format(parameterized_parts), params]
         end
 
-        message = "No route matches #{Hash[constraints.sort_by{|k,v| k.to_s}].inspect}"
-        message << " missing required keys: #{missing_keys.sort.inspect}" if missing_keys && !missing_keys.empty?
+        unmatched_keys = (missing_keys || []) & constraints.keys
+        missing_keys = (missing_keys || []) - unmatched_keys
+
+        message = "No route matches #{Hash[constraints.sort_by { |k, v| k.to_s }].inspect}".dup
+        message << ", missing required keys: #{missing_keys.sort.inspect}" if missing_keys && !missing_keys.empty?
+        message << ", possible unmatched constraints: #{unmatched_keys.sort.inspect}" if unmatched_keys && !unmatched_keys.empty?
 
         raise ActionController::UrlGenerationError, message
       end
@@ -87,7 +94,11 @@ module ActionDispatch
           else
             routes = non_recursive(cache, options)
 
-            hash = routes.group_by { |_, r| r.score(options) }
+            supplied_keys = options.each_with_object({}) do |(k, v), h|
+              h[k.to_s] = true if v
+            end
+
+            hash = routes.group_by { |_, r| r.score(supplied_keys) }
 
             hash.keys.sort.reverse_each do |score|
               break if score < 0
@@ -174,4 +185,5 @@ module ActionDispatch
         end
     end
   end
+  # :startdoc:
 end
diff --git a/actionpack/lib/action_dispatch/journey/gtg/builder.rb b/actionpack/lib/action_dispatch/journey/gtg/builder.rb
index 450588cda6..44c31053cb 100644
--- a/actionpack/lib/action_dispatch/journey/gtg/builder.rb
+++ b/actionpack/lib/action_dispatch/journey/gtg/builder.rb
@@ -1,4 +1,6 @@
-require 'action_dispatch/journey/gtg/transition_table'
+# frozen_string_literal: true
+
+require "action_dispatch/journey/gtg/transition_table"
 
 module ActionDispatch
   module Journey # :nodoc:
@@ -17,7 +19,7 @@ module ActionDispatch
         def transition_table
           dtrans   = TransitionTable.new
           marked   = {}
-          state_id = Hash.new { |h,k| h[k] = h.length }
+          state_id = Hash.new { |h, k| h[k] = h.length }
 
           start   = firstpos(root)
           dstates = [start]
@@ -75,7 +77,7 @@ module ActionDispatch
           when Nodes::Unary
             nullable?(node.left)
           else
-            raise ArgumentError, 'unknown nullable: %s' % node.class.name
+            raise ArgumentError, "unknown nullable: %s" % node.class.name
           end
         end
 
@@ -96,7 +98,7 @@ module ActionDispatch
           when Nodes::Terminal
             nullable?(node) ? [] : [node]
           else
-            raise ArgumentError, 'unknown firstpos: %s' % node.class.name
+            raise ArgumentError, "unknown firstpos: %s" % node.class.name
           end
         end
 
@@ -117,7 +119,7 @@ module ActionDispatch
           when Nodes::Unary
             lastpos(node.left)
           else
-            raise ArgumentError, 'unknown lastpos: %s' % node.class.name
+            raise ArgumentError, "unknown lastpos: %s" % node.class.name
           end
         end
 
diff --git a/actionpack/lib/action_dispatch/journey/gtg/simulator.rb b/actionpack/lib/action_dispatch/journey/gtg/simulator.rb
index 94b0a24344..2ee4f5c30c 100644
--- a/actionpack/lib/action_dispatch/journey/gtg/simulator.rb
+++ b/actionpack/lib/action_dispatch/journey/gtg/simulator.rb
@@ -1,4 +1,6 @@
-require 'strscan'
+# frozen_string_literal: true
+
+require "strscan"
 
 module ActionDispatch
   module Journey # :nodoc:
@@ -18,14 +20,6 @@ module ActionDispatch
           @tt = transition_table
         end
 
-        def simulate(string)
-          ms = memos(string) { return }
-          MatchData.new(ms)
-        end
-
-        alias :=~    :simulate
-        alias :match :simulate
-
         def memos(string)
           input = StringScanner.new(string)
           state = [0]
diff --git a/actionpack/lib/action_dispatch/journey/gtg/transition_table.rb b/actionpack/lib/action_dispatch/journey/gtg/transition_table.rb
index d7ce6042c2..ea647e051a 100644
--- a/actionpack/lib/action_dispatch/journey/gtg/transition_table.rb
+++ b/actionpack/lib/action_dispatch/journey/gtg/transition_table.rb
@@ -1,4 +1,6 @@
-require 'action_dispatch/journey/nfa/dot'
+# frozen_string_literal: true
+
+require "action_dispatch/journey/nfa/dot"
 
 module ActionDispatch
   module Journey # :nodoc:
@@ -12,7 +14,7 @@ module ActionDispatch
           @regexp_states = {}
           @string_states = {}
           @accepting     = {}
-          @memos         = Hash.new { |h,k| h[k] = [] }
+          @memos         = Hash.new { |h, k| h[k] = [] }
         end
 
         def add_accepting(state)
@@ -56,7 +58,7 @@ module ActionDispatch
         end
 
         def as_json(options = nil)
-          simple_regexp = Hash.new { |h,k| h[k] = {} }
+          simple_regexp = Hash.new { |h, k| h[k] = {} }
 
           @regexp_states.each do |from, hash|
             hash.each do |re, to|
@@ -72,20 +74,20 @@ module ActionDispatch
         end
 
         def to_svg
-          svg = IO.popen('dot -Tsvg', 'w+') { |f|
+          svg = IO.popen("dot -Tsvg", "w+") { |f|
             f.write(to_dot)
             f.close_write
             f.readlines
           }
           3.times { svg.shift }
-          svg.join.sub(/width="[^"]*"/, '').sub(/height="[^"]*"/, '')
+          svg.join.sub(/width="[^"]*"/, "").sub(/height="[^"]*"/, "")
         end
 
-        def visualizer(paths, title = 'FSM')
-          viz_dir   = File.join File.dirname(__FILE__), '..', 'visualizer'
-          fsm_js    = File.read File.join(viz_dir, 'fsm.js')
-          fsm_css   = File.read File.join(viz_dir, 'fsm.css')
-          erb       = File.read File.join(viz_dir, 'index.html.erb')
+        def visualizer(paths, title = "FSM")
+          viz_dir   = File.join __dir__, "..", "visualizer"
+          fsm_js    = File.read File.join(viz_dir, "fsm.js")
+          fsm_css   = File.read File.join(viz_dir, "fsm.css")
+          erb       = File.read File.join(viz_dir, "index.html.erb")
           states    = "function tt() { return #{to_json}; }"
 
           fun_routes = paths.sample(3).map do |ast|
@@ -93,10 +95,10 @@ module ActionDispatch
               case n
               when Nodes::Symbol
                 case n.left
-                when ':id' then rand(100).to_s
-                when ':format' then %w{ xml json }.sample
+                when ":id" then rand(100).to_s
+                when ":format" then %w{ xml json }.sample
                 else
-                  'omg'
+                  "omg"
                 end
               when Nodes::Terminal then n.symbol
               else
@@ -109,13 +111,12 @@ module ActionDispatch
           svg         = to_svg
           javascripts = [states, fsm_js]
 
-          # Annoying hack warnings
           fun_routes  = fun_routes
           stylesheets = stylesheets
           svg         = svg
           javascripts = javascripts
 
-          require 'erb'
+          require "erb"
           template = ERB.new erb
           template.result(binding)
         end
@@ -148,7 +149,7 @@ module ActionDispatch
             when Regexp
               @regexp_states
             else
-              raise ArgumentError, 'unknown symbol: %s' % sym.class
+              raise ArgumentError, "unknown symbol: %s" % sym.class
             end
           end
       end
diff --git a/actionpack/lib/action_dispatch/journey/nfa/builder.rb b/actionpack/lib/action_dispatch/journey/nfa/builder.rb
index ee6494c3e4..d22302e101 100644
--- a/actionpack/lib/action_dispatch/journey/nfa/builder.rb
+++ b/actionpack/lib/action_dispatch/journey/nfa/builder.rb
@@ -1,5 +1,7 @@
-require 'action_dispatch/journey/nfa/transition_table'
-require 'action_dispatch/journey/gtg/transition_table'
+# frozen_string_literal: true
+
+require "action_dispatch/journey/nfa/transition_table"
+require "action_dispatch/journey/gtg/transition_table"
 
 module ActionDispatch
   module Journey # :nodoc:
@@ -36,7 +38,7 @@ module ActionDispatch
         def visit_OR(node)
           from = @i += 1
           children = node.children.map { |c| visit(c) }
-          to   = @i += 1
+          to = @i += 1
 
           children.each do |child|
             @tt[from, child.first] = nil
diff --git a/actionpack/lib/action_dispatch/journey/nfa/dot.rb b/actionpack/lib/action_dispatch/journey/nfa/dot.rb
index 7063b44bb5..56e9e3c83d 100644
--- a/actionpack/lib/action_dispatch/journey/nfa/dot.rb
+++ b/actionpack/lib/action_dispatch/journey/nfa/dot.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActionDispatch
   module Journey # :nodoc:
     module NFA # :nodoc:
@@ -7,18 +9,18 @@ module ActionDispatch
             "  #{from} -> #{to} [label=\"#{sym || 'ε'}\"];"
           }
 
-          #memo_nodes = memos.values.flatten.map { |n|
-          #  label = n
-          #  if Journey::Route === n
-          #    label = "#{n.verb.source} #{n.path.spec}"
-          #  end
-          #  "  #{n.object_id} [label=\"#{label}\", shape=box];"
-          #}
-          #memo_edges = memos.flat_map { |k, memos|
-          #  (memos || []).map { |v| "  #{k} -> #{v.object_id};" }
-          #}.uniq
+          # memo_nodes = memos.values.flatten.map { |n|
+          #   label = n
+          #   if Journey::Route === n
+          #     label = "#{n.verb.source} #{n.path.spec}"
+          #   end
+          #   "  #{n.object_id} [label=\"#{label}\", shape=box];"
+          # }
+          # memo_edges = memos.flat_map { |k, memos|
+          #   (memos || []).map { |v| "  #{k} -> #{v.object_id};" }
+          # }.uniq
 
-        <<-eodot
+          <<-eodot
 digraph nfa {
   rankdir=LR;
   node [shape = doublecircle];
@@ -26,7 +28,7 @@ digraph nfa {
   node [shape = circle];
 #{edges.join "\n"}
 }
-        eodot
+          eodot
         end
       end
     end
diff --git a/actionpack/lib/action_dispatch/journey/nfa/simulator.rb b/actionpack/lib/action_dispatch/journey/nfa/simulator.rb
index b23270db3c..8efe48d91c 100644
--- a/actionpack/lib/action_dispatch/journey/nfa/simulator.rb
+++ b/actionpack/lib/action_dispatch/journey/nfa/simulator.rb
@@ -1,4 +1,6 @@
-require 'strscan'
+# frozen_string_literal: true
+
+require "strscan"
 
 module ActionDispatch
   module Journey # :nodoc:
diff --git a/actionpack/lib/action_dispatch/journey/nfa/transition_table.rb b/actionpack/lib/action_dispatch/journey/nfa/transition_table.rb
index 0ccab21801..fe55861507 100644
--- a/actionpack/lib/action_dispatch/journey/nfa/transition_table.rb
+++ b/actionpack/lib/action_dispatch/journey/nfa/transition_table.rb
@@ -1,4 +1,6 @@
-require 'action_dispatch/journey/nfa/dot'
+# frozen_string_literal: true
+
+require "action_dispatch/journey/nfa/dot"
 
 module ActionDispatch
   module Journey # :nodoc:
@@ -10,7 +12,7 @@ module ActionDispatch
         attr_reader :memos
 
         def initialize
-          @table     = Hash.new { |h,f| h[f] = {} }
+          @table     = Hash.new { |h, f| h[f] = {} }
           @memos     = {}
           @accepting = nil
           @inverted  = nil
diff --git a/actionpack/lib/action_dispatch/journey/nodes/node.rb b/actionpack/lib/action_dispatch/journey/nodes/node.rb
index 2793c5668d..08b931a3cd 100644
--- a/actionpack/lib/action_dispatch/journey/nodes/node.rb
+++ b/actionpack/lib/action_dispatch/journey/nodes/node.rb
@@ -1,4 +1,6 @@
-require 'action_dispatch/journey/visitors'
+# frozen_string_literal: true
+
+require "action_dispatch/journey/visitors"
 
 module ActionDispatch
   module Journey # :nodoc:
@@ -18,7 +20,7 @@ module ActionDispatch
         end
 
         def to_s
-          Visitors::String::INSTANCE.accept(self, '')
+          Visitors::String::INSTANCE.accept(self, "")
         end
 
         def to_dot
@@ -30,7 +32,7 @@ module ActionDispatch
         end
 
         def name
-          left.tr '*:'.freeze, ''.freeze
+          left.tr "*:".freeze, "".freeze
         end
 
         def type
@@ -80,7 +82,7 @@ module ActionDispatch
         def initialize(left)
           super
           @regexp = DEFAULT_EXP
-          @name = left.tr '*:'.freeze, ''.freeze
+          @name = left.tr "*:".freeze, "".freeze
         end
 
         def default_regexp?
@@ -104,7 +106,7 @@ module ActionDispatch
         def type; :STAR; end
 
         def name
-          left.name.tr '*:', ''
+          left.name.tr "*:", ""
         end
       end
 
diff --git a/actionpack/lib/action_dispatch/journey/parser.rb b/actionpack/lib/action_dispatch/journey/parser.rb
index 9012297400..e002755bcf 100644
--- a/actionpack/lib/action_dispatch/journey/parser.rb
+++ b/actionpack/lib/action_dispatch/journey/parser.rb
@@ -1,32 +1,33 @@
 #
 # DO NOT MODIFY!!!!
-# This file is automatically generated by Racc 1.4.11
-# from Racc grammer file "".
+# This file is automatically generated by Racc 1.4.14
+# from Racc grammar file "".
 #
 
 require 'racc/parser.rb'
 
+# :stopdoc:
 
-require 'action_dispatch/journey/parser_extras'
+require "action_dispatch/journey/parser_extras"
 module ActionDispatch
   module Journey
     class Parser < Racc::Parser
 ##### State transition tables begin ###
 
 racc_action_table = [
-    13,    15,    14,     7,    21,    16,     8,    19,    13,    15,
-    14,     7,    17,    16,     8,    13,    15,    14,     7,    24,
-    16,     8,    13,    15,    14,     7,    19,    16,     8 ]
+    13,    15,    14,     7,    19,    16,     8,    19,    13,    15,
+    14,     7,    17,    16,     8,    13,    15,    14,     7,    21,
+    16,     8,    13,    15,    14,     7,    24,    16,     8 ]
 
 racc_action_check = [
-     2,     2,     2,     2,    17,     2,     2,     2,     0,     0,
-     0,     0,     1,     0,     0,    19,    19,    19,    19,    20,
-    19,    19,     7,     7,     7,     7,    22,     7,     7 ]
+     2,     2,     2,     2,    22,     2,     2,     2,    19,    19,
+    19,    19,     1,    19,    19,     7,     7,     7,     7,    17,
+     7,     7,     0,     0,     0,     0,    20,     0,     0 ]
 
 racc_action_pointer = [
-     6,    12,    -2,   nil,   nil,   nil,   nil,    20,   nil,   nil,
-   nil,   nil,   nil,   nil,   nil,   nil,   nil,     4,   nil,    13,
-    13,   nil,    17,   nil,   nil ]
+    20,    12,    -2,   nil,   nil,   nil,   nil,    13,   nil,   nil,
+   nil,   nil,   nil,   nil,   nil,   nil,   nil,    19,   nil,     6,
+    20,   nil,    -5,   nil,   nil ]
 
 racc_action_default = [
    -19,   -19,    -2,    -3,    -4,    -5,    -6,   -19,   -10,   -11,
@@ -134,11 +135,11 @@ Racc_debug_parser = false
 # reduce 0 omitted
 
 def _reduce_1(val, _values)
- Cat.new(val.first, val.last)
+ Cat.new(val.first, val.last) 
 end
 
 def _reduce_2(val, _values)
- val.first
+ val.first 
 end
 
 # reduce 3 omitted
@@ -150,19 +151,19 @@ end
 # reduce 6 omitted
 
 def _reduce_7(val, _values)
- Group.new(val[1])
+ Group.new(val[1]) 
 end
 
 def _reduce_8(val, _values)
- Or.new([val.first, val.last])
+ Or.new([val.first, val.last]) 
 end
 
 def _reduce_9(val, _values)
- Or.new([val.first, val.last])
+ Or.new([val.first, val.last]) 
 end
 
 def _reduce_10(val, _values)
- Star.new(Symbol.new(val.last))
+ Star.new(Symbol.new(val.last)) 
 end
 
 # reduce 11 omitted
@@ -174,19 +175,19 @@ end
 # reduce 14 omitted
 
 def _reduce_15(val, _values)
- Slash.new('/')
+ Slash.new(val.first) 
 end
 
 def _reduce_16(val, _values)
- Symbol.new(val.first)
+ Symbol.new(val.first) 
 end
 
 def _reduce_17(val, _values)
- Literal.new(val.first)
+ Literal.new(val.first) 
 end
 
 def _reduce_18(val, _values)
- Dot.new(val.first)
+ Dot.new(val.first) 
 end
 
 def _reduce_none(val, _values)
diff --git a/actionpack/lib/action_dispatch/journey/parser.y b/actionpack/lib/action_dispatch/journey/parser.y
index d3f7c4d765..f9b1a7a958 100644
--- a/actionpack/lib/action_dispatch/journey/parser.y
+++ b/actionpack/lib/action_dispatch/journey/parser.y
@@ -30,7 +30,7 @@ rule
     | dot
     ;
   slash
-    : SLASH              { Slash.new('/') }
+    : SLASH              { Slash.new(val.first) }
     ;
   symbol
     : SYMBOL             { Symbol.new(val.first) }
@@ -45,5 +45,6 @@ rule
 end
 
 ---- header
+# :stopdoc:
 
-require 'action_dispatch/journey/parser_extras'
+require "action_dispatch/journey/parser_extras"
diff --git a/actionpack/lib/action_dispatch/journey/parser_extras.rb b/actionpack/lib/action_dispatch/journey/parser_extras.rb
index fff0299812..18ec6c9b9b 100644
--- a/actionpack/lib/action_dispatch/journey/parser_extras.rb
+++ b/actionpack/lib/action_dispatch/journey/parser_extras.rb
@@ -1,9 +1,12 @@
-require 'action_dispatch/journey/scanner'
-require 'action_dispatch/journey/nodes/node'
+# frozen_string_literal: true
+
+require "action_dispatch/journey/scanner"
+require "action_dispatch/journey/nodes/node"
 
 module ActionDispatch
-  module Journey # :nodoc:
-    class Parser < Racc::Parser # :nodoc:
+  # :stopdoc:
+  module Journey
+    class Parser < Racc::Parser
       include Journey::Nodes
 
       def self.parse(string)
@@ -24,4 +27,5 @@ module ActionDispatch
       end
     end
   end
+  # :startdoc:
 end
diff --git a/actionpack/lib/action_dispatch/journey/path/pattern.rb b/actionpack/lib/action_dispatch/journey/path/pattern.rb
index 018b89a2b7..2d85a89a56 100644
--- a/actionpack/lib/action_dispatch/journey/path/pattern.rb
+++ b/actionpack/lib/action_dispatch/journey/path/pattern.rb
@@ -1,10 +1,12 @@
+# frozen_string_literal: true
+
 module ActionDispatch
   module Journey # :nodoc:
     module Path # :nodoc:
       class Pattern # :nodoc:
         attr_reader :spec, :requirements, :anchored
 
-        def self.from_string string
+        def self.from_string(string)
           build(string, {}, "/.?", true)
         end
 
@@ -31,6 +33,13 @@ module ActionDispatch
           Visitors::FormatBuilder.new.accept(spec)
         end
 
+        def eager_load!
+          required_names
+          offsets
+          to_regexp
+          nil
+        end
+
         def ast
           @spec.find_all(&:symbol?).each do |node|
             re = @requirements[node.to_sym]
@@ -98,7 +107,7 @@ module ActionDispatch
           end
 
           def visit_STAR(node)
-            re = @matchers[node.left.to_sym] || '.+'
+            re = @matchers[node.left.to_sym] || ".+"
             "(#{re})"
           end
 
@@ -175,7 +184,7 @@ module ActionDispatch
 
               if @requirements.key?(node)
                 re = /#{@requirements[node]}|/
-                @offsets.push((re.match('').length - 1) + @offsets.last)
+                @offsets.push((re.match("").length - 1) + @offsets.last)
               else
                 @offsets << @offsets.last
               end
diff --git a/actionpack/lib/action_dispatch/journey/route.rb b/actionpack/lib/action_dispatch/journey/route.rb
index cfd6681dd1..8165709a3d 100644
--- a/actionpack/lib/action_dispatch/journey/route.rb
+++ b/actionpack/lib/action_dispatch/journey/route.rb
@@ -1,6 +1,9 @@
+# frozen_string_literal: true
+
 module ActionDispatch
-  module Journey # :nodoc:
-    class Route # :nodoc:
+  # :stopdoc:
+  module Journey
+    class Route
       attr_reader :app, :path, :defaults, :name, :precedence
 
       attr_reader :constraints, :internal
@@ -9,11 +12,11 @@ module ActionDispatch
       module VerbMatchers
         VERBS = %w{ DELETE GET HEAD OPTIONS LINK PATCH POST PUT TRACE UNLINK }
         VERBS.each do |v|
-          class_eval <<-eoc
-          class #{v}
-            def self.verb; name.split("::").last; end
-            def self.call(req); req.#{v.downcase}?; end
-          end
+          class_eval <<-eoc, __FILE__, __LINE__ + 1
+            class #{v}
+              def self.verb; name.split("::").last; end
+              def self.call(req); req.#{v.downcase}?; end
+            end
           eoc
         end
 
@@ -29,16 +32,15 @@ module ActionDispatch
 
         class All
           def self.call(_); true; end
-          def self.verb; ''; end
+          def self.verb; ""; end
         end
 
-        VERB_TO_CLASS = VERBS.each_with_object({ :all => All }) do |verb, hash|
+        VERB_TO_CLASS = VERBS.each_with_object(all: All) do |verb, hash|
           klass = const_get verb
           hash[verb]                 = klass
           hash[verb.downcase]        = klass
           hash[verb.downcase.to_sym] = klass
         end
-
       end
 
       def self.verb_matcher(verb)
@@ -73,6 +75,14 @@ module ActionDispatch
         @internal          = internal
       end
 
+      def eager_load!
+        path.eager_load!
+        ast
+        parts
+        required_defaults
+        nil
+      end
+
       def ast
         @decorated_ast ||= begin
           decorated_ast = path.ast
@@ -81,9 +91,16 @@ module ActionDispatch
         end
       end
 
-      def requirements # :nodoc:
-        # needed for rails `rails routes`
-        @defaults.merge(path.requirements).delete_if { |_,v|
+      # Needed for `rails routes`. Picks up succinctly defined requirements
+      # for a route, for example route
+      #
+      #   get 'photo/:id', :controller => 'photos', :action => 'show',
+      #     :id => /[A-Z]\d{5}/
+      #
+      # will have {:controller=>"photos", :action=>"show", :id=>/[A-Z]\d{5}/}
+      # as requirements.
+      def requirements
+        @defaults.merge(path.requirements).delete_if { |_, v|
           /.+?/ == v
         }
       end
@@ -96,13 +113,18 @@ module ActionDispatch
         required_parts + required_defaults.keys
       end
 
-      def score(constraints)
+      def score(supplied_keys)
         required_keys = path.required_names
-        supplied_keys = constraints.map { |k,v| v && k.to_s }.compact
 
-        return -1 unless (required_keys - supplied_keys).empty?
+        required_keys.each do |k|
+          return -1 unless supplied_keys.include?(k)
+        end
+
+        score = 0
+        path.names.each do |k|
+          score += 1 if supplied_keys.include?(k)
+        end
 
-        score = (supplied_keys & path.names).length
         score + (required_defaults.length * 2)
       end
 
@@ -124,7 +146,7 @@ module ActionDispatch
       end
 
       def required_defaults
-        @required_defaults ||= @defaults.dup.delete_if do |k,_|
+        @required_defaults ||= @defaults.dup.delete_if do |k, _|
           parts.include?(k) || !required_default?(k)
         end
       end
@@ -164,17 +186,18 @@ module ActionDispatch
       end
 
       def verb
-        verbs.join('|')
+        verbs.join("|")
       end
 
       private
-      def verbs
-        @request_method_match.map(&:verb)
-      end
+        def verbs
+          @request_method_match.map(&:verb)
+        end
 
-      def match_verb(request)
-        @request_method_match.any? { |m| m.call request }
-      end
+        def match_verb(request)
+          @request_method_match.any? { |m| m.call request }
+        end
     end
   end
+  # :startdoc:
 end
diff --git a/actionpack/lib/action_dispatch/journey/router.rb b/actionpack/lib/action_dispatch/journey/router.rb
index 06cdce1724..30af3ff930 100644
--- a/actionpack/lib/action_dispatch/journey/router.rb
+++ b/actionpack/lib/action_dispatch/journey/router.rb
@@ -1,14 +1,16 @@
-require 'action_dispatch/journey/router/utils'
-require 'action_dispatch/journey/routes'
-require 'action_dispatch/journey/formatter'
+# frozen_string_literal: true
+
+require "action_dispatch/journey/router/utils"
+require "action_dispatch/journey/routes"
+require "action_dispatch/journey/formatter"
 
 before = $-w
 $-w = false
-require 'action_dispatch/journey/parser'
+require "action_dispatch/journey/parser"
 $-w = before
 
-require 'action_dispatch/journey/route'
-require 'action_dispatch/journey/path/pattern'
+require "action_dispatch/journey/route"
+require "action_dispatch/journey/path/pattern"
 
 module ActionDispatch
   module Journey # :nodoc:
@@ -22,6 +24,13 @@ module ActionDispatch
         @routes = routes
       end
 
+      def eager_load!
+        # Eagerly trigger the simulator's initialization so
+        # it doesn't happen during a request cycle.
+        simulator
+        nil
+      end
+
       def serve(req)
         find_routes(req).each do |match, parameters, route|
           set_params  = req.path_parameters
@@ -29,16 +38,20 @@ module ActionDispatch
           script_name = req.script_name
 
           unless route.path.anchored
-            req.script_name = (script_name.to_s + match.to_s).chomp('/')
+            req.script_name = (script_name.to_s + match.to_s).chomp("/")
             req.path_info = match.post_match
             req.path_info = "/" + req.path_info unless req.path_info.start_with? "/"
           end
 
+          parameters = route.defaults.merge parameters.transform_values { |val|
+            val.dup.force_encoding(::Encoding::UTF_8)
+          }
+
           req.path_parameters = set_params.merge parameters
 
           status, headers, body = route.app.serve(req)
 
-          if 'pass' == headers['X-Cascade']
+          if "pass" == headers["X-Cascade"]
             req.script_name     = script_name
             req.path_info       = path_info
             req.path_parameters = set_params
@@ -48,7 +61,7 @@ module ActionDispatch
           return [status, headers, body]
         end
 
-        return [404, {'X-Cascade' => 'pass'}, ['Not Found']]
+        [404, { "X-Cascade" => "pass" }, ["Not Found"]]
       end
 
       def recognize(rails_req)
@@ -58,6 +71,7 @@ module ActionDispatch
             rails_req.path_info   = match.post_match.sub(/^([^\/])/, '/\1')
           end
 
+          parameters = route.defaults.merge parameters
           yield(route, parameters)
         end
       end
@@ -72,7 +86,9 @@ module ActionDispatch
       private
 
         def partitioned_routes
-          routes.partitioned_routes
+          routes.partition { |r|
+            r.path.anchored && r.ast.grep(Nodes::Symbol).all? { |n| n.default_regexp?  }
+          }
         end
 
         def ast
@@ -92,7 +108,7 @@ module ActionDispatch
           simulator.memos(path) { [] }
         end
 
-        def find_routes req
+        def find_routes(req)
           routes = filter_routes(req.path_info).concat custom_routes.find_all { |r|
             r.path.match(req.path_info)
           }
@@ -107,9 +123,9 @@ module ActionDispatch
           routes.sort_by!(&:precedence)
 
           routes.map! { |r|
-            match_data  = r.path.match(req.path_info)
-            path_parameters = r.defaults.dup
-            match_data.names.zip(match_data.captures) { |name,val|
+            match_data = r.path.match(req.path_info)
+            path_parameters = {}
+            match_data.names.zip(match_data.captures) { |name, val|
               path_parameters[name.to_sym] = Utils.unescape_uri(val) if val
             }
             [match_data, path_parameters, r]
diff --git a/actionpack/lib/action_dispatch/journey/router/utils.rb b/actionpack/lib/action_dispatch/journey/router/utils.rb
index 9793ca1c7a..df3f79a407 100644
--- a/actionpack/lib/action_dispatch/journey/router/utils.rb
+++ b/actionpack/lib/action_dispatch/journey/router/utils.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActionDispatch
   module Journey # :nodoc:
     class Router # :nodoc:
@@ -5,7 +7,7 @@ module ActionDispatch
         # Normalizes URI path.
         #
         # Strips off trailing slash and ensures there is a leading slash.
-        # Also converts downcase url encoded string to uppercase.
+        # Also converts downcase URL encoded string to uppercase.
         #
         #   normalize_path("/foo")  # => "/foo"
         #   normalize_path("/foo/") # => "/foo"
@@ -13,22 +15,25 @@ module ActionDispatch
         #   normalize_path("")      # => "/"
         #   normalize_path("/%ab")  # => "/%AB"
         def self.normalize_path(path)
-          path = "/#{path}"
-          path.squeeze!('/'.freeze)
-          path.sub!(%r{/+\Z}, ''.freeze)
+          path ||= ""
+          encoding = path.encoding
+          path = "/#{path}".dup
+          path.squeeze!("/".freeze)
+          path.sub!(%r{/+\Z}, "".freeze)
           path.gsub!(/(%[a-f0-9]{2})/) { $1.upcase }
-          path = '/' if path == ''.freeze
+          path = "/".dup if path == "".freeze
+          path.force_encoding(encoding)
           path
         end
 
         # URI path and fragment escaping
-        # http://tools.ietf.org/html/rfc3986
+        # https://tools.ietf.org/html/rfc3986
         class UriEncoder # :nodoc:
           ENCODE   = "%%%02X".freeze
           US_ASCII = Encoding::US_ASCII
           UTF_8    = Encoding::UTF_8
-          EMPTY    = "".force_encoding(US_ASCII).freeze
-          DEC2HEX  = (0..255).to_a.map{ |i| ENCODE % i }.map{ |s| s.force_encoding(US_ASCII) }
+          EMPTY    = "".dup.force_encoding(US_ASCII).freeze
+          DEC2HEX  = (0..255).to_a.map { |i| ENCODE % i }.map { |s| s.force_encoding(US_ASCII) }
 
           ALPHA = "a-zA-Z".freeze
           DIGIT = "0-9".freeze
@@ -55,12 +60,12 @@ module ActionDispatch
 
           def unescape_uri(uri)
             encoding = uri.encoding == US_ASCII ? UTF_8 : uri.encoding
-            uri.gsub(ESCAPED) { |match| [match[1, 2].hex].pack('C') }.force_encoding(encoding)
+            uri.gsub(ESCAPED) { |match| [match[1, 2].hex].pack("C") }.force_encoding(encoding)
           end
 
-          protected
+          private
             def escape(component, pattern)
-              component.gsub(pattern){ |unsafe| percent_encode(unsafe) }.force_encoding(US_ASCII)
+              component.gsub(pattern) { |unsafe| percent_encode(unsafe) }.force_encoding(US_ASCII)
             end
 
             def percent_encode(unsafe)
@@ -84,6 +89,10 @@ module ActionDispatch
           ENCODER.escape_fragment(fragment.to_s)
         end
 
+        # Replaces any escaped sequences with their unescaped representations.
+        #
+        #   uri = "/topics?title=Ruby%20on%20Rails"
+        #   unescape_uri(uri)  #=> "/topics?title=Ruby on Rails"
         def self.unescape_uri(uri)
           ENCODER.unescape_uri(uri)
         end
diff --git a/actionpack/lib/action_dispatch/journey/routes.rb b/actionpack/lib/action_dispatch/journey/routes.rb
index f7b009109e..639c063495 100644
--- a/actionpack/lib/action_dispatch/journey/routes.rb
+++ b/actionpack/lib/action_dispatch/journey/routes.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActionDispatch
   module Journey # :nodoc:
     # The Routing table. Contains all routes for a system. Routes can be
diff --git a/actionpack/lib/action_dispatch/journey/scanner.rb b/actionpack/lib/action_dispatch/journey/scanner.rb
index 19e0bc03d6..4ae77903fa 100644
--- a/actionpack/lib/action_dispatch/journey/scanner.rb
+++ b/actionpack/lib/action_dispatch/journey/scanner.rb
@@ -1,4 +1,6 @@
-require 'strscan'
+# frozen_string_literal: true
+
+require "strscan"
 
 module ActionDispatch
   module Journey # :nodoc:
@@ -35,22 +37,23 @@ module ActionDispatch
         def scan
           case
             # /
-          when text = @ss.scan(/\//)
-            [:SLASH, text]
+          when @ss.skip(/\//)
+            [:SLASH, "/"]
+          when @ss.skip(/\(/)
+            [:LPAREN, "("]
+          when @ss.skip(/\)/)
+            [:RPAREN, ")"]
+          when @ss.skip(/\|/)
+            [:OR, "|"]
+          when @ss.skip(/\./)
+            [:DOT, "."]
+          when text = @ss.scan(/:\w+/)
+            [:SYMBOL, text]
           when text = @ss.scan(/\*\w+/)
             [:STAR, text]
-          when text = @ss.scan(/(?<!\\)\(/)
-            [:LPAREN, text]
-          when text = @ss.scan(/(?<!\\)\)/)
-            [:RPAREN, text]
-          when text = @ss.scan(/\|/)
-            [:OR, text]
-          when text = @ss.scan(/\./)
-            [:DOT, text]
-          when text = @ss.scan(/(?<!\\):\w+/)
-            [:SYMBOL, text]
-          when text = @ss.scan(/(?:[\w%\-~!$&'*+,;=@]|\\:|\\\(|\\\))+/)
-            [:LITERAL, text.tr('\\', '')]
+          when text = @ss.scan(/(?:[\w%\-~!$&'*+,;=@]|\\[:()])+/)
+            text.tr! "\\", ""
+            [:LITERAL, text]
             # any char
           when text = @ss.scan(/./)
             [:LITERAL, text]
diff --git a/actionpack/lib/action_dispatch/journey/visitors.rb b/actionpack/lib/action_dispatch/journey/visitors.rb
index 306d2e674a..3395471a85 100644
--- a/actionpack/lib/action_dispatch/journey/visitors.rb
+++ b/actionpack/lib/action_dispatch/journey/visitors.rb
@@ -1,10 +1,13 @@
+# frozen_string_literal: true
+
 module ActionDispatch
-  module Journey # :nodoc:
+  # :stopdoc:
+  module Journey
     class Format
       ESCAPE_PATH    = ->(value) { Router::Utils.escape_path(value) }
       ESCAPE_SEGMENT = ->(value) { Router::Utils.escape_segment(value) }
 
-      class Parameter < Struct.new(:name, :escaper)
+      Parameter = Struct.new(:name, :escaper) do
         def escape(value); escaper.call value; end
       end
 
@@ -21,7 +24,7 @@ module ActionDispatch
         @children   = []
         @parameters = []
 
-        parts.each_with_index do |object,i|
+        parts.each_with_index do |object, i|
           case object
           when Journey::Format
             @children << i
@@ -37,7 +40,7 @@ module ActionDispatch
         @parameters.each do |index|
           param = parts[index]
           value = hash[param.name]
-          return ''.freeze unless value
+          return "".freeze unless value
           parts[index] = param.escape value
         end
 
@@ -57,7 +60,7 @@ module ActionDispatch
 
         private
 
-          def visit node
+          def visit(node)
             send(DISPATCH_CACHE[node.type], node)
           end
 
@@ -97,7 +100,7 @@ module ActionDispatch
           visit(node, seed)
         end
 
-        def visit node, seed
+        def visit(node, seed)
           send(DISPATCH_CACHE[node.type], node, seed)
         end
 
@@ -153,7 +156,7 @@ module ActionDispatch
         end
       end
 
-      # Loop through the requirements AST
+      # Loop through the requirements AST.
       class Each < FunctionalVisitor # :nodoc:
         def visit(node, block)
           block.call(node)
@@ -166,28 +169,28 @@ module ActionDispatch
       class String < FunctionalVisitor # :nodoc:
         private
 
-        def binary(node, seed)
-          visit(node.right, visit(node.left, seed))
-        end
+          def binary(node, seed)
+            visit(node.right, visit(node.left, seed))
+          end
 
-        def nary(node, seed)
-          last_child = node.children.last
-          node.children.inject(seed) { |s, c|
-            string = visit(c, s)
-            string << "|".freeze unless last_child == c
-            string
-          }
-        end
+          def nary(node, seed)
+            last_child = node.children.last
+            node.children.inject(seed) { |s, c|
+              string = visit(c, s)
+              string << "|" unless last_child == c
+              string
+            }
+          end
 
-        def terminal(node, seed)
-          seed + node.left
-        end
+          def terminal(node, seed)
+            seed + node.left
+          end
 
-        def visit_GROUP(node, seed)
-          visit(node.left, seed << "(".freeze) << ")".freeze
-        end
+          def visit_GROUP(node, seed)
+            visit(node.left, seed.dup << "(") << ")"
+          end
 
-        INSTANCE = new
+          INSTANCE = new
       end
 
       class Dot < FunctionalVisitor # :nodoc:
@@ -261,4 +264,5 @@ module ActionDispatch
       end
     end
   end
+  # :startdoc:
 end
diff --git a/actionpack/lib/action_dispatch/middleware/callbacks.rb b/actionpack/lib/action_dispatch/middleware/callbacks.rb
index c782779b34..5b2ad36dd5 100644
--- a/actionpack/lib/action_dispatch/middleware/callbacks.rb
+++ b/actionpack/lib/action_dispatch/middleware/callbacks.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 
 module ActionDispatch
   # Provides callbacks to be executed before and after dispatching the request.
@@ -7,17 +8,6 @@ module ActionDispatch
     define_callbacks :call
 
     class << self
-      def to_prepare(*args, &block)
-        ActiveSupport::Reloader.to_prepare(*args, &block)
-      end
-
-      def to_cleanup(*args, &block)
-        ActiveSupport::Reloader.to_complete(*args, &block)
-      end
-
-      deprecate to_prepare: 'use ActiveSupport::Reloader.to_prepare instead',
-        to_cleanup: 'use ActiveSupport::Reloader.to_complete instead'
-
       def before(*args, &block)
         set_callback(:call, :before, *args, &block)
       end
diff --git a/actionpack/lib/action_dispatch/middleware/cookies.rb b/actionpack/lib/action_dispatch/middleware/cookies.rb
index f2f3150b56..ea4156c972 100644
--- a/actionpack/lib/action_dispatch/middleware/cookies.rb
+++ b/actionpack/lib/action_dispatch/middleware/cookies.rb
@@ -1,13 +1,15 @@
-require 'active_support/core_ext/hash/keys'
-require 'active_support/key_generator'
-require 'active_support/message_verifier'
-require 'active_support/json'
-require 'rack/utils'
+# frozen_string_literal: true
+
+require "active_support/core_ext/hash/keys"
+require "active_support/key_generator"
+require "active_support/message_verifier"
+require "active_support/json"
+require "rack/utils"
 
 module ActionDispatch
   class Request
     def cookie_jar
-      fetch_header('action_dispatch.cookies'.freeze) do
+      fetch_header("action_dispatch.cookies".freeze) do
         self.cookie_jar = Cookies::CookieJar.build(self, cookies)
       end
     end
@@ -20,11 +22,11 @@ module ActionDispatch
     }
 
     def have_cookie_jar?
-      has_header? 'action_dispatch.cookies'.freeze
+      has_header? "action_dispatch.cookies".freeze
     end
 
     def cookie_jar=(jar)
-      set_header 'action_dispatch.cookies'.freeze, jar
+      set_header "action_dispatch.cookies".freeze, jar
     end
 
     def key_generator
@@ -43,6 +45,22 @@ module ActionDispatch
       get_header Cookies::ENCRYPTED_SIGNED_COOKIE_SALT
     end
 
+    def authenticated_encrypted_cookie_salt
+      get_header Cookies::AUTHENTICATED_ENCRYPTED_COOKIE_SALT
+    end
+
+    def use_authenticated_cookie_encryption
+      get_header Cookies::USE_AUTHENTICATED_COOKIE_ENCRYPTION
+    end
+
+    def encrypted_cookie_cipher
+      get_header Cookies::ENCRYPTED_COOKIE_CIPHER
+    end
+
+    def signed_cookie_digest
+      get_header Cookies::SIGNED_COOKIE_DIGEST
+    end
+
     def secret_token
       get_header Cookies::SECRET_TOKEN
     end
@@ -58,6 +76,11 @@ module ActionDispatch
     def cookies_digest
       get_header Cookies::COOKIES_DIGEST
     end
+
+    def cookies_rotations
+      get_header Cookies::COOKIES_ROTATIONS
+    end
+
     # :startdoc:
   end
 
@@ -77,16 +100,17 @@ module ActionDispatch
   #   cookies[:lat_lon] = JSON.generate([47.68, -122.37])
   #
   #   # Sets a cookie that expires in 1 hour.
-  #   cookies[:login] = { value: "XJ-122", expires: 1.hour.from_now }
+  #   cookies[:login] = { value: "XJ-122", expires: 1.hour }
+  #
+  #   # Sets a cookie that expires at a specific time.
+  #   cookies[:login] = { value: "XJ-122", expires: Time.utc(2020, 10, 15, 5) }
   #
   #   # Sets a signed cookie, which prevents users from tampering with its value.
-  #   # The cookie is signed by your app's `secrets.secret_key_base` value.
   #   # It can be read using the signed method `cookies.signed[:name]`
   #   cookies.signed[:user_id] = current_user.id
   #
   #   # Sets an encrypted cookie value before sending it to the client which
   #   # prevent users from reading and tampering with its value.
-  #   # The cookie is signed by your app's `secrets.secret_key_base` value.
   #   # It can be read using the encrypted method `cookies.encrypted[:name]`
   #   cookies.encrypted[:discount] = 45
   #
@@ -94,7 +118,7 @@ module ActionDispatch
   #   cookies.permanent[:login] = "XJ-122"
   #
   #   # You can also chain these methods:
-  #   cookies.permanent.signed[:login] = "XJ-122"
+  #   cookies.signed.permanent[:login] = "XJ-122"
   #
   # Examples of reading:
   #
@@ -112,7 +136,7 @@ module ActionDispatch
   #
   #  cookies[:name] = {
   #    value: 'a yummy cookie',
-  #    expires: 1.year.from_now,
+  #    expires: 1.year,
   #    domain: 'domain.com'
   #  }
   #
@@ -137,8 +161,8 @@ module ActionDispatch
   #
   # * <tt>:tld_length</tt> - When using <tt>:domain => :all</tt>, this option can be used to explicitly
   #   set the TLD length when using a short (<= 3 character) domain that is being interpreted as part of a TLD.
-  #   For example, to share cookies between user1.lvh.me and user2.lvh.me, set <tt>:tld_length</tt> to 1.
-  # * <tt>:expires</tt> - The time at which this cookie expires, as a \Time object.
+  #   For example, to share cookies between user1.lvh.me and user2.lvh.me, set <tt>:tld_length</tt> to 2.
+  # * <tt>:expires</tt> - The time at which this cookie expires, as a \Time or ActiveSupport::Duration object.
   # * <tt>:secure</tt> - Whether this cookie is only transmitted to HTTPS servers.
   #   Default is +false+.
   # * <tt>:httponly</tt> - Whether this cookie is accessible via scripting or
@@ -149,10 +173,15 @@ module ActionDispatch
     SIGNED_COOKIE_SALT = "action_dispatch.signed_cookie_salt".freeze
     ENCRYPTED_COOKIE_SALT = "action_dispatch.encrypted_cookie_salt".freeze
     ENCRYPTED_SIGNED_COOKIE_SALT = "action_dispatch.encrypted_signed_cookie_salt".freeze
+    AUTHENTICATED_ENCRYPTED_COOKIE_SALT = "action_dispatch.authenticated_encrypted_cookie_salt".freeze
+    USE_AUTHENTICATED_COOKIE_ENCRYPTION = "action_dispatch.use_authenticated_cookie_encryption".freeze
+    ENCRYPTED_COOKIE_CIPHER = "action_dispatch.encrypted_cookie_cipher".freeze
+    SIGNED_COOKIE_DIGEST = "action_dispatch.signed_cookie_digest".freeze
     SECRET_TOKEN = "action_dispatch.secret_token".freeze
     SECRET_KEY_BASE = "action_dispatch.secret_key_base".freeze
     COOKIES_SERIALIZER = "action_dispatch.cookies_serializer".freeze
     COOKIES_DIGEST = "action_dispatch.cookies_digest".freeze
+    COOKIES_ROTATIONS = "action_dispatch.cookies_rotations".freeze
 
     # Cookies can typically store 4096 bytes.
     MAX_COOKIE_SIZE = 4096
@@ -160,7 +189,7 @@ module ActionDispatch
     # Raised when storing more than 4K of session data.
     CookieOverflow = Class.new StandardError
 
-    # Include in a cookie jar to allow chaining, e.g. cookies.permanent.signed
+    # Include in a cookie jar to allow chaining, e.g. cookies.permanent.signed.
     module ChainedCookieJars
       # Returns a jar that'll automatically set the assigned cookies to have an expiration date 20 years from now. Example:
       #
@@ -179,12 +208,12 @@ module ActionDispatch
 
       # Returns a jar that'll automatically generate a signed representation of cookie value and verify it when reading from
       # the cookie again. This is useful for creating cookies with values that the user is not supposed to change. If a signed
-      # cookie was tampered with by the user (or a 3rd party), nil will be returned.
+      # cookie was tampered with by the user (or a 3rd party), +nil+ will be returned.
       #
-      # If +secrets.secret_key_base+ and +secrets.secret_token+ (deprecated) are both set,
+      # If +secret_key_base+ and +secrets.secret_token+ (deprecated) are both set,
       # legacy cookies signed with the old key generator will be transparently upgraded.
       #
-      # This jar requires that you set a suitable secret for the verification on your app's +secrets.secret_key_base+.
+      # This jar requires that you set a suitable secret for the verification on your app's +secret_key_base+.
       #
       # Example:
       #
@@ -193,35 +222,28 @@ module ActionDispatch
       #
       #   cookies.signed[:discount] # => 45
       def signed
-        @signed ||=
-          if upgrade_legacy_signed_cookies?
-            UpgradeLegacySignedCookieJar.new(self)
-          else
-            SignedCookieJar.new(self)
-          end
+        @signed ||= SignedKeyRotatingCookieJar.new(self)
       end
 
       # Returns a jar that'll automatically encrypt cookie values before sending them to the client and will decrypt them for read.
-      # If the cookie was tampered with by the user (or a 3rd party), nil will be returned.
+      # If the cookie was tampered with by the user (or a 3rd party), +nil+ will be returned.
       #
-      # If +secrets.secret_key_base+ and +secrets.secret_token+ (deprecated) are both set,
+      # If +secret_key_base+ and +secrets.secret_token+ (deprecated) are both set,
       # legacy cookies signed with the old key generator will be transparently upgraded.
       #
-      # This jar requires that you set a suitable secret for the verification on your app's +secrets.secret_key_base+.
+      # If +config.action_dispatch.encrypted_cookie_salt+ and +config.action_dispatch.encrypted_signed_cookie_salt+
+      # are both set, legacy cookies encrypted with HMAC AES-256-CBC will be transparently upgraded.
+      #
+      # This jar requires that you set a suitable secret for the verification on your app's +secret_key_base+.
       #
       # Example:
       #
       #   cookies.encrypted[:discount] = 45
-      #   # => Set-Cookie: discount=ZS9ZZ1R4cG1pcUJ1bm80anhQang3dz09LS1mbDZDSU5scGdOT3ltQ2dTdlhSdWpRPT0%3D--ab54663c9f4e3bc340c790d6d2b71e92f5b60315; path=/
+      #   # => Set-Cookie: discount=DIQ7fw==--K3n//8vvnSbGq9dA--7Xh91HfLpwzbj1czhBiwOg==; path=/
       #
       #   cookies.encrypted[:discount] # => 45
       def encrypted
-        @encrypted ||=
-          if upgrade_legacy_signed_cookies?
-            UpgradeLegacyEncryptedCookieJar.new(self)
-          else
-            EncryptedCookieJar.new(self)
-          end
+        @encrypted ||= EncryptedKeyRotatingCookieJar.new(self)
       end
 
       # Returns the +signed+ or +encrypted+ jar, preferring +encrypted+ if +secret_key_base+ is set.
@@ -237,32 +259,23 @@ module ActionDispatch
 
       private
 
-      def upgrade_legacy_signed_cookies?
-        request.secret_token.present? && request.secret_key_base.present?
-      end
-    end
+        def upgrade_legacy_signed_cookies?
+          request.secret_token.present? && request.secret_key_base.present?
+        end
 
-    # Passing the ActiveSupport::MessageEncryptor::NullSerializer downstream
-    # to the Message{Encryptor,Verifier} allows us to handle the
-    # (de)serialization step within the cookie jar, which gives us the
-    # opportunity to detect and migrate legacy cookies.
-    module VerifyAndUpgradeLegacySignedMessage # :nodoc:
-      def initialize(*args)
-        super
-        @legacy_verifier = ActiveSupport::MessageVerifier.new(request.secret_token, serializer: ActiveSupport::MessageEncryptor::NullSerializer)
-      end
+        def upgrade_legacy_hmac_aes_cbc_cookies?
+          request.secret_key_base.present? &&
+            request.encrypted_signed_cookie_salt.present? &&
+            request.encrypted_cookie_salt.present? &&
+            request.use_authenticated_cookie_encryption
+        end
 
-      def verify_and_upgrade_legacy_signed_message(name, signed_message)
-        deserialize(name, @legacy_verifier.verify(signed_message)).tap do |value|
-          self[name] = { value: value }
+        def encrypted_cookie_cipher
+          request.encrypted_cookie_cipher || "aes-256-gcm"
         end
-      rescue ActiveSupport::MessageVerifier::InvalidSignature
-        nil
-      end
 
-      private
-        def parse(name, signed_message)
-          super || verify_and_upgrade_legacy_signed_message(name, signed_message)
+        def signed_cookie_digest
+          request.signed_cookie_digest || "SHA1"
         end
     end
 
@@ -332,30 +345,34 @@ module ActionDispatch
 
       def update_cookies_from_jar
         request_jar = @request.cookie_jar.instance_variable_get(:@cookies)
-        set_cookies = request_jar.reject { |k,_| @delete_cookies.key?(k) }
+        set_cookies = request_jar.reject { |k, _| @delete_cookies.key?(k) }
 
         @cookies.update set_cookies if set_cookies
       end
 
       def to_header
-        @cookies.map { |k,v| "#{escape(k)}=#{escape(v)}" }.join '; '
+        @cookies.map { |k, v| "#{escape(k)}=#{escape(v)}" }.join "; "
       end
 
-      def handle_options(options) #:nodoc:
+      def handle_options(options) # :nodoc:
+        if options[:expires].respond_to?(:from_now)
+          options[:expires] = options[:expires].from_now
+        end
+
         options[:path] ||= "/"
 
-        if options[:domain] == :all || options[:domain] == 'all'
-          # if there is a provided tld length then we use it otherwise default domain regexp
+        if options[:domain] == :all || options[:domain] == "all"
+          # If there is a provided tld length then we use it otherwise default domain regexp.
           domain_regexp = options[:tld_length] ? /([^.]+\.?){#{options[:tld_length]}}$/ : DOMAIN_REGEXP
 
-          # if host is not ip and matches domain regexp
+          # If host is not ip and matches domain regexp.
           # (ip confirms to domain regexp so we explicitly check for ip)
           options[:domain] = if (request.host !~ /^[\d.]+$/) && (request.host =~ domain_regexp)
             ".#{$&}"
           end
         elsif options[:domain].is_a? Array
-          # if host matches one of the supplied domains without a dot in front of it
-          options[:domain] = options[:domain].find {|domain| request.host.include? domain.sub(/^\./, '') }
+          # If host matches one of the supplied domains without a dot in front of it.
+          options[:domain] = options[:domain].find { |domain| request.host.include? domain.sub(/^\./, "") }
         end
       end
 
@@ -367,12 +384,12 @@ module ActionDispatch
           value = options[:value]
         else
           value = options
-          options = { :value => value }
+          options = { value: value }
         end
 
         handle_options(options)
 
-        if @cookies[name.to_s] != value or options[:expires]
+        if @cookies[name.to_s] != value || options[:expires]
           @cookies[name.to_s] = value
           @set_cookies[name.to_s] = options
           @delete_cookies.delete(name.to_s)
@@ -404,9 +421,9 @@ module ActionDispatch
         @delete_cookies[name.to_s] == options
       end
 
-      # Removes all cookies on the client machine by calling <tt>delete</tt> for each cookie
+      # Removes all cookies on the client machine by calling <tt>delete</tt> for each cookie.
       def clear(options = {})
-        @cookies.each_key{ |k| delete(k, options) }
+        @cookies.each_key { |k| delete(k, options) }
       end
 
       def write(headers)
@@ -415,31 +432,30 @@ module ActionDispatch
         end
       end
 
-      mattr_accessor :always_write_cookie
-      self.always_write_cookie = false
+      mattr_accessor :always_write_cookie, default: false
 
       private
 
-      def escape(string)
-        ::Rack::Utils.escape(string)
-      end
+        def escape(string)
+          ::Rack::Utils.escape(string)
+        end
 
-      def make_set_cookie_header(header)
-        header = @set_cookies.inject(header) { |m, (k, v)|
-          if write_cookie?(v)
-            ::Rack::Utils.add_cookie_to_header(m, k, v)
-          else
-            m
-          end
-        }
-        @delete_cookies.inject(header) { |m, (k, v)|
-          ::Rack::Utils.add_remove_cookie_to_header(m, k, v)
-        }
-      end
+        def make_set_cookie_header(header)
+          header = @set_cookies.inject(header) { |m, (k, v)|
+            if write_cookie?(v)
+              ::Rack::Utils.add_cookie_to_header(m, k, v)
+            else
+              m
+            end
+          }
+          @delete_cookies.inject(header) { |m, (k, v)|
+            ::Rack::Utils.add_remove_cookie_to_header(m, k, v)
+          }
+        end
 
-      def write_cookie?(cookie)
-        request.ssl? || !cookie[:secure] || always_write_cookie
-      end
+        def write_cookie?(cookie)
+          request.ssl? || !cookie[:secure] || always_write_cookie
+        end
     end
 
     class AbstractCookieJar # :nodoc:
@@ -470,6 +486,14 @@ module ActionDispatch
         def request; @parent_jar.request; end
 
       private
+        def expiry_options(options)
+          if options[:expires].respond_to?(:from_now)
+            { expires_in: options[:expires] }
+          else
+            { expires_at: options[:expires] }
+          end
+        end
+
         def parse(name, data); data; end
         def commit(options); end
     end
@@ -493,6 +517,7 @@ module ActionDispatch
 
     module SerializedCookieJars # :nodoc:
       MARSHAL_SIGNATURE = "\x04\x08".freeze
+      SERIALIZER = ActiveSupport::MessageEncryptor::NullSerializer
 
       protected
         def needs_migration?(value)
@@ -503,12 +528,16 @@ module ActionDispatch
           serializer.dump(value)
         end
 
-        def deserialize(name, value)
+        def deserialize(name)
+          rotate = false
+          value  = yield -> { rotate = true }
+
           if value
-            if needs_migration?(value)
-              Marshal.load(value).tap do |v|
-                self[name] = { value: v }
-              end
+            case
+            when needs_migration?(value)
+              self[name] = Marshal.load(value)
+            when rotate
+              self[name] = serializer.load(value)
             else
               serializer.load(value)
             end
@@ -528,79 +557,100 @@ module ActionDispatch
         end
 
         def digest
-          request.cookies_digest || 'SHA1'
-        end
-
-        def key_generator
-          request.key_generator
+          request.cookies_digest || "SHA1"
         end
     end
 
-    class SignedCookieJar < AbstractCookieJar # :nodoc:
+    class SignedKeyRotatingCookieJar < AbstractCookieJar # :nodoc:
       include SerializedCookieJars
 
       def initialize(parent_jar)
         super
-        secret = key_generator.generate_key(request.signed_cookie_salt)
-        @verifier = ActiveSupport::MessageVerifier.new(secret, digest: digest, serializer: ActiveSupport::MessageEncryptor::NullSerializer)
+
+        secret = request.key_generator.generate_key(request.signed_cookie_salt)
+        @verifier = ActiveSupport::MessageVerifier.new(secret, digest: signed_cookie_digest, serializer: SERIALIZER)
+
+        request.cookies_rotations.signed.each do |*secrets, **options|
+          @verifier.rotate(*secrets, serializer: SERIALIZER, **options)
+        end
+
+        if upgrade_legacy_signed_cookies?
+          @verifier.rotate request.secret_token, serializer: SERIALIZER
+        end
       end
 
       private
         def parse(name, signed_message)
-          deserialize name, @verifier.verified(signed_message)
+          deserialize(name) do |rotate|
+            @verifier.verified(signed_message, on_rotation: rotate)
+          end
         end
 
         def commit(options)
-          options[:value] = @verifier.generate(serialize(options[:value]))
+          options[:value] = @verifier.generate(serialize(options[:value]), expiry_options(options))
 
           raise CookieOverflow if options[:value].bytesize > MAX_COOKIE_SIZE
         end
     end
 
-    # UpgradeLegacySignedCookieJar is used instead of SignedCookieJar if
-    # secrets.secret_token and secrets.secret_key_base are both set. It reads
-    # legacy cookies signed with the old dummy key generator and signs and
-    # re-saves them using the new key generator to provide a smooth upgrade path.
-    class UpgradeLegacySignedCookieJar < SignedCookieJar #:nodoc:
-      include VerifyAndUpgradeLegacySignedMessage
-    end
-
-    class EncryptedCookieJar < AbstractCookieJar # :nodoc:
+    class EncryptedKeyRotatingCookieJar < AbstractCookieJar # :nodoc:
       include SerializedCookieJars
 
       def initialize(parent_jar)
         super
 
-        if ActiveSupport::LegacyKeyGenerator === key_generator
-          raise "You didn't set secrets.secret_key_base, which is required for this cookie jar. " +
-            "Read the upgrade documentation to learn more about this new config option."
+        if request.use_authenticated_cookie_encryption
+          key_len = ActiveSupport::MessageEncryptor.key_len(encrypted_cookie_cipher)
+          secret = request.key_generator.generate_key(request.authenticated_encrypted_cookie_salt, key_len)
+          @encryptor = ActiveSupport::MessageEncryptor.new(secret, cipher: encrypted_cookie_cipher, serializer: SERIALIZER)
+        else
+          key_len = ActiveSupport::MessageEncryptor.key_len("aes-256-cbc")
+          secret = request.key_generator.generate_key(request.encrypted_cookie_salt, key_len)
+          sign_secret = request.key_generator.generate_key(request.encrypted_signed_cookie_salt)
+          @encryptor = ActiveSupport::MessageEncryptor.new(secret, sign_secret, cipher: "aes-256-cbc", serializer: SERIALIZER)
+        end
+
+        request.cookies_rotations.encrypted.each do |*secrets, **options|
+          @encryptor.rotate(*secrets, serializer: SERIALIZER, **options)
+        end
+
+        if upgrade_legacy_hmac_aes_cbc_cookies?
+          legacy_cipher = "aes-256-cbc"
+          secret = request.key_generator.generate_key(request.encrypted_cookie_salt, ActiveSupport::MessageEncryptor.key_len(legacy_cipher))
+          sign_secret = request.key_generator.generate_key(request.encrypted_signed_cookie_salt)
+
+          @encryptor.rotate(secret, sign_secret, cipher: legacy_cipher, digest: digest, serializer: SERIALIZER)
         end
 
-        secret = key_generator.generate_key(request.encrypted_cookie_salt || '')
-        sign_secret = key_generator.generate_key(request.encrypted_signed_cookie_salt || '')
-        @encryptor = ActiveSupport::MessageEncryptor.new(secret, sign_secret, digest: digest, serializer: ActiveSupport::MessageEncryptor::NullSerializer)
+        if upgrade_legacy_signed_cookies?
+          @legacy_verifier = ActiveSupport::MessageVerifier.new(request.secret_token, digest: digest, serializer: SERIALIZER)
+        end
       end
 
       private
         def parse(name, encrypted_message)
-          deserialize name, @encryptor.decrypt_and_verify(encrypted_message)
-        rescue ActiveSupport::MessageVerifier::InvalidSignature, ActiveSupport::MessageEncryptor::InvalidMessage
-          nil
+          deserialize(name) do |rotate|
+            @encryptor.decrypt_and_verify(encrypted_message, on_rotation: rotate)
+          end
+        rescue ActiveSupport::MessageEncryptor::InvalidMessage, ActiveSupport::MessageVerifier::InvalidSignature
+          parse_legacy_signed_message(name, encrypted_message)
         end
 
         def commit(options)
-          options[:value] = @encryptor.encrypt_and_sign(serialize(options[:value]))
+          options[:value] = @encryptor.encrypt_and_sign(serialize(options[:value]), expiry_options(options))
 
           raise CookieOverflow if options[:value].bytesize > MAX_COOKIE_SIZE
         end
-    end
 
-    # UpgradeLegacyEncryptedCookieJar is used by ActionDispatch::Session::CookieStore
-    # instead of EncryptedCookieJar if secrets.secret_token and secrets.secret_key_base
-    # are both set. It reads legacy cookies signed with the old dummy key generator and
-    # encrypts and re-saves them using the new key generator to provide a smooth upgrade path.
-    class UpgradeLegacyEncryptedCookieJar < EncryptedCookieJar #:nodoc:
-      include VerifyAndUpgradeLegacySignedMessage
+        def parse_legacy_signed_message(name, legacy_signed_message)
+          if defined?(@legacy_verifier)
+            deserialize(name) do |rotate|
+              rotate.call
+
+              @legacy_verifier.verified(legacy_signed_message)
+            end
+          end
+        end
     end
 
     def initialize(app)
diff --git a/actionpack/lib/action_dispatch/middleware/debug_exceptions.rb b/actionpack/lib/action_dispatch/middleware/debug_exceptions.rb
index 5f758d641a..511306eb0e 100644
--- a/actionpack/lib/action_dispatch/middleware/debug_exceptions.rb
+++ b/actionpack/lib/action_dispatch/middleware/debug_exceptions.rb
@@ -1,16 +1,18 @@
-require 'action_dispatch/http/request'
-require 'action_dispatch/middleware/exception_wrapper'
-require 'action_dispatch/routing/inspector'
-require 'action_view'
-require 'action_view/base'
+# frozen_string_literal: true
 
-require 'pp'
+require "action_dispatch/http/request"
+require "action_dispatch/middleware/exception_wrapper"
+require "action_dispatch/routing/inspector"
+require "action_view"
+require "action_view/base"
+
+require "pp"
 
 module ActionDispatch
   # This middleware is responsible for logging exceptions and
   # showing a debugging page in case the request is local.
   class DebugExceptions
-    RESCUES_TEMPLATE_PATH = File.expand_path('../templates', __FILE__)
+    RESCUES_TEMPLATE_PATH = File.expand_path("templates", __dir__)
 
     class DebugView < ActionView::Base
       def debug_params(params)
@@ -19,23 +21,33 @@ module ActionDispatch
         clean_params.delete("controller")
 
         if clean_params.empty?
-          'None'
+          "None"
         else
-          PP.pp(clean_params, "", 200)
+          PP.pp(clean_params, "".dup, 200)
         end
       end
 
       def debug_headers(headers)
         if headers.present?
-          headers.inspect.gsub(',', ",\n")
+          headers.inspect.gsub(",", ",\n")
         else
-          'None'
+          "None"
         end
       end
 
       def debug_hash(object)
         object.to_hash.sort_by { |k, _| k.to_s }.map { |k, v| "#{k}: #{v.inspect rescue $!.message}" }.join("\n")
       end
+
+      def render(*)
+        logger = ActionView::Base.logger
+
+        if logger && logger.respond_to?(:silence)
+          logger.silence { super }
+        else
+          super
+        end
+      end
     end
 
     def initialize(app, routes_app = nil, response_format = :default)
@@ -48,7 +60,7 @@ module ActionDispatch
       request = ActionDispatch::Request.new env
       _, headers, body = response = @app.call(env)
 
-      if headers['X-Cascade'] == 'pass'
+      if headers["X-Cascade"] == "pass"
         body.close if body.respond_to?(:close)
         raise ActionController::RoutingError, "No route matches [#{env['REQUEST_METHOD']}] #{env['PATH_INFO'].inspect}"
       end
@@ -61,129 +73,133 @@ module ActionDispatch
 
     private
 
-    def render_exception(request, exception)
-      backtrace_cleaner = request.get_header('action_dispatch.backtrace_cleaner')
-      wrapper = ExceptionWrapper.new(backtrace_cleaner, exception)
-      log_error(request, wrapper)
+      def render_exception(request, exception)
+        backtrace_cleaner = request.get_header("action_dispatch.backtrace_cleaner")
+        wrapper = ExceptionWrapper.new(backtrace_cleaner, exception)
+        log_error(request, wrapper)
 
-      if request.get_header('action_dispatch.show_detailed_exceptions')
-        content_type = request.formats.first
+        if request.get_header("action_dispatch.show_detailed_exceptions")
+          content_type = request.formats.first
 
-        if api_request?(content_type)
-          render_for_api_request(content_type, wrapper)
+          if api_request?(content_type)
+            render_for_api_request(content_type, wrapper)
+          else
+            render_for_browser_request(request, wrapper)
+          end
         else
-          render_for_browser_request(request, wrapper)
+          raise exception
         end
-      else
-        raise exception
       end
-    end
 
-    def render_for_browser_request(request, wrapper)
-      template = create_template(request, wrapper)
-      file = "rescues/#{wrapper.rescue_template}"
+      def render_for_browser_request(request, wrapper)
+        template = create_template(request, wrapper)
+        file = "rescues/#{wrapper.rescue_template}"
 
-      if request.xhr?
-        body = template.render(template: file, layout: false, formats: [:text])
-        format = "text/plain"
-      else
-        body = template.render(template: file, layout: 'rescues/layout')
-        format = "text/html"
+        if request.xhr?
+          body = template.render(template: file, layout: false, formats: [:text])
+          format = "text/plain"
+        else
+          body = template.render(template: file, layout: "rescues/layout")
+          format = "text/html"
+        end
+        render(wrapper.status_code, body, format)
       end
-      render(wrapper.status_code, body, format)
-    end
-
-    def render_for_api_request(content_type, wrapper)
-      body = {
-        status: wrapper.status_code,
-        error:  Rack::Utils::HTTP_STATUS_CODES.fetch(
-          wrapper.status_code,
-          Rack::Utils::HTTP_STATUS_CODES[500]
-        ),
-        exception: wrapper.exception.inspect,
-        traces: wrapper.traces
-      }
 
-      to_format = "to_#{content_type.to_sym}"
+      def render_for_api_request(content_type, wrapper)
+        body = {
+          status: wrapper.status_code,
+          error:  Rack::Utils::HTTP_STATUS_CODES.fetch(
+            wrapper.status_code,
+            Rack::Utils::HTTP_STATUS_CODES[500]
+          ),
+          exception: wrapper.exception.inspect,
+          traces: wrapper.traces
+        }
+
+        to_format = "to_#{content_type.to_sym}"
+
+        if content_type && body.respond_to?(to_format)
+          formatted_body = body.public_send(to_format)
+          format = content_type
+        else
+          formatted_body = body.to_json
+          format = Mime[:json]
+        end
 
-      if content_type && body.respond_to?(to_format)
-        formatted_body = body.public_send(to_format)
-        format = content_type
-      else
-        formatted_body = body.to_json
-        format = Mime[:json]
+        render(wrapper.status_code, formatted_body, format)
       end
 
-      render(wrapper.status_code, formatted_body, format)
-    end
+      def create_template(request, wrapper)
+        traces = wrapper.traces
 
-    def create_template(request, wrapper)
-      traces = wrapper.traces
+        trace_to_show = "Application Trace"
+        if traces[trace_to_show].empty? && wrapper.rescue_template != "routing_error"
+          trace_to_show = "Full Trace"
+        end
 
-      trace_to_show = 'Application Trace'
-      if traces[trace_to_show].empty? && wrapper.rescue_template != 'routing_error'
-        trace_to_show = 'Full Trace'
-      end
+        if source_to_show = traces[trace_to_show].first
+          source_to_show_id = source_to_show[:id]
+        end
 
-      if source_to_show = traces[trace_to_show].first
-        source_to_show_id = source_to_show[:id]
+        DebugView.new([RESCUES_TEMPLATE_PATH],
+          request: request,
+          exception: wrapper.exception,
+          traces: traces,
+          show_source_idx: source_to_show_id,
+          trace_to_show: trace_to_show,
+          routes_inspector: routes_inspector(wrapper.exception),
+          source_extracts: wrapper.source_extracts,
+          line_number: wrapper.line_number,
+          file: wrapper.file
+        )
       end
 
-      DebugView.new([RESCUES_TEMPLATE_PATH],
-        request: request,
-        exception: wrapper.exception,
-        traces: traces,
-        show_source_idx: source_to_show_id,
-        trace_to_show: trace_to_show,
-        routes_inspector: routes_inspector(wrapper.exception),
-        source_extracts: wrapper.source_extracts,
-        line_number: wrapper.line_number,
-        file: wrapper.file
-      )
-    end
-
-    def render(status, body, format)
-      [status, {'Content-Type' => "#{format}; charset=#{Response.default_charset}", 'Content-Length' => body.bytesize.to_s}, [body]]
-    end
+      def render(status, body, format)
+        [status, { "Content-Type" => "#{format}; charset=#{Response.default_charset}", "Content-Length" => body.bytesize.to_s }, [body]]
+      end
 
-    def log_error(request, wrapper)
-      logger = logger(request)
-      return unless logger
+      def log_error(request, wrapper)
+        logger = logger(request)
+        return unless logger
 
-      exception = wrapper.exception
+        exception = wrapper.exception
 
-      trace = wrapper.application_trace
-      trace = wrapper.framework_trace if trace.empty?
+        trace = wrapper.application_trace
+        trace = wrapper.framework_trace if trace.empty?
 
-      ActiveSupport::Deprecation.silence do
-        logger.fatal "  "
-        logger.fatal "#{exception.class} (#{exception.message}):"
-        log_array logger, exception.annoted_source_code if exception.respond_to?(:annoted_source_code)
-        logger.fatal "  "
-        log_array logger, trace
+        ActiveSupport::Deprecation.silence do
+          logger.fatal "  "
+          logger.fatal "#{exception.class} (#{exception.message}):"
+          log_array logger, exception.annoted_source_code if exception.respond_to?(:annoted_source_code)
+          logger.fatal "  "
+          log_array logger, trace
+        end
       end
-    end
 
-    def log_array(logger, array)
-      array.map { |line| logger.fatal line }
-    end
+      def log_array(logger, array)
+        if logger.formatter && logger.formatter.respond_to?(:tags_text)
+          logger.fatal array.join("\n#{logger.formatter.tags_text}")
+        else
+          logger.fatal array.join("\n")
+        end
+      end
 
-    def logger(request)
-      request.logger || ActionView::Base.logger || stderr_logger
-    end
+      def logger(request)
+        request.logger || ActionView::Base.logger || stderr_logger
+      end
 
-    def stderr_logger
-      @stderr_logger ||= ActiveSupport::Logger.new($stderr)
-    end
+      def stderr_logger
+        @stderr_logger ||= ActiveSupport::Logger.new($stderr)
+      end
 
-    def routes_inspector(exception)
-      if @routes_app.respond_to?(:routes) && (exception.is_a?(ActionController::RoutingError) || exception.is_a?(ActionView::Template::Error))
-        ActionDispatch::Routing::RoutesInspector.new(@routes_app.routes.routes)
+      def routes_inspector(exception)
+        if @routes_app.respond_to?(:routes) && (exception.is_a?(ActionController::RoutingError) || exception.is_a?(ActionView::Template::Error))
+          ActionDispatch::Routing::RoutesInspector.new(@routes_app.routes.routes)
+        end
       end
-    end
 
-    def api_request?(content_type)
-      @response_format == :api && !content_type.html?
-    end
+      def api_request?(content_type)
+        @response_format == :api && !content_type.html?
+      end
   end
 end
diff --git a/actionpack/lib/action_dispatch/middleware/debug_locks.rb b/actionpack/lib/action_dispatch/middleware/debug_locks.rb
new file mode 100644
index 0000000000..03760438f7
--- /dev/null
+++ b/actionpack/lib/action_dispatch/middleware/debug_locks.rb
@@ -0,0 +1,124 @@
+# frozen_string_literal: true
+
+module ActionDispatch
+  # This middleware can be used to diagnose deadlocks in the autoload interlock.
+  #
+  # To use it, insert it near the top of the middleware stack, using
+  # <tt>config/application.rb</tt>:
+  #
+  #     config.middleware.insert_before Rack::Sendfile, ActionDispatch::DebugLocks
+  #
+  # After restarting the application and re-triggering the deadlock condition,
+  # <tt>/rails/locks</tt> will show a summary of all threads currently known to
+  # the interlock, which lock level they are holding or awaiting, and their
+  # current backtrace.
+  #
+  # Generally a deadlock will be caused by the interlock conflicting with some
+  # other external lock or blocking I/O call. These cannot be automatically
+  # identified, but should be visible in the displayed backtraces.
+  #
+  # NOTE: The formatting and content of this middleware's output is intended for
+  # human consumption, and should be expected to change between releases.
+  #
+  # This middleware exposes operational details of the server, with no access
+  # control. It should only be enabled when in use, and removed thereafter.
+  class DebugLocks
+    def initialize(app, path = "/rails/locks")
+      @app = app
+      @path = path
+    end
+
+    def call(env)
+      req = ActionDispatch::Request.new env
+
+      if req.get?
+        path = req.path_info.chomp("/".freeze)
+        if path == @path
+          return render_details(req)
+        end
+      end
+
+      @app.call(env)
+    end
+
+    private
+      def render_details(req)
+        threads = ActiveSupport::Dependencies.interlock.raw_state do |raw_threads|
+          # The Interlock itself comes to a complete halt as long as this block
+          # is executing. That gives us a more consistent picture of everything,
+          # but creates a pretty strong Observer Effect.
+          #
+          # Most directly, that means we need to do as little as possible in
+          # this block. More widely, it means this middleware should remain a
+          # strictly diagnostic tool (to be used when something has gone wrong),
+          # and not for any sort of general monitoring.
+
+          raw_threads.each.with_index do |(thread, info), idx|
+            info[:index] = idx
+            info[:backtrace] = thread.backtrace
+          end
+
+          raw_threads
+        end
+
+        str = threads.map do |thread, info|
+          if info[:exclusive]
+            lock_state = "Exclusive".dup
+          elsif info[:sharing] > 0
+            lock_state = "Sharing".dup
+            lock_state << " x#{info[:sharing]}" if info[:sharing] > 1
+          else
+            lock_state = "No lock".dup
+          end
+
+          if info[:waiting]
+            lock_state << " (yielded share)"
+          end
+
+          msg = "Thread #{info[:index]} [0x#{thread.__id__.to_s(16)} #{thread.status || 'dead'}]  #{lock_state}\n".dup
+
+          if info[:sleeper]
+            msg << "  Waiting in #{info[:sleeper]}"
+            msg << " to #{info[:purpose].to_s.inspect}" unless info[:purpose].nil?
+            msg << "\n"
+
+            if info[:compatible]
+              compat = info[:compatible].map { |c| c == false ? "share" : c.to_s.inspect }
+              msg << "  may be pre-empted for: #{compat.join(', ')}\n"
+            end
+
+            blockers = threads.values.select { |binfo| blocked_by?(info, binfo, threads.values) }
+            msg << "  blocked by: #{blockers.map { |i| i[:index] }.join(', ')}\n" if blockers.any?
+          end
+
+          blockees = threads.values.select { |binfo| blocked_by?(binfo, info, threads.values) }
+          msg << "  blocking: #{blockees.map { |i| i[:index] }.join(', ')}\n" if blockees.any?
+
+          msg << "\n#{info[:backtrace].join("\n")}\n" if info[:backtrace]
+        end.join("\n\n---\n\n\n")
+
+        [200, { "Content-Type" => "text/plain", "Content-Length" => str.size }, [str]]
+      end
+
+      def blocked_by?(victim, blocker, all_threads)
+        return false if victim.equal?(blocker)
+
+        case victim[:sleeper]
+        when :start_sharing
+          blocker[:exclusive] ||
+            (!victim[:waiting] && blocker[:compatible] && !blocker[:compatible].include?(false))
+        when :start_exclusive
+          blocker[:sharing] > 0 ||
+            blocker[:exclusive] ||
+            (blocker[:compatible] && !blocker[:compatible].include?(victim[:purpose]))
+        when :yield_shares
+          blocker[:exclusive]
+        when :stop_exclusive
+          blocker[:exclusive] ||
+            victim[:compatible] &&
+            victim[:compatible].include?(blocker[:purpose]) &&
+            all_threads.all? { |other| !other[:compatible] || blocker.equal?(other) || other[:compatible].include?(blocker[:purpose]) }
+        end
+      end
+  end
+end
diff --git a/actionpack/lib/action_dispatch/middleware/exception_wrapper.rb b/actionpack/lib/action_dispatch/middleware/exception_wrapper.rb
index 59edc66086..4f69abfa6f 100644
--- a/actionpack/lib/action_dispatch/middleware/exception_wrapper.rb
+++ b/actionpack/lib/action_dispatch/middleware/exception_wrapper.rb
@@ -1,33 +1,31 @@
-require 'active_support/core_ext/module/attribute_accessors'
-require 'rack/utils'
+# frozen_string_literal: true
+
+require "active_support/core_ext/module/attribute_accessors"
+require "rack/utils"
 
 module ActionDispatch
   class ExceptionWrapper
-    cattr_accessor :rescue_responses
-    @@rescue_responses = Hash.new(:internal_server_error)
-    @@rescue_responses.merge!(
-      'ActionController::RoutingError'                => :not_found,
-      'AbstractController::ActionNotFound'            => :not_found,
-      'ActionController::MethodNotAllowed'            => :method_not_allowed,
-      'ActionController::UnknownHttpMethod'           => :method_not_allowed,
-      'ActionController::NotImplemented'              => :not_implemented,
-      'ActionController::UnknownFormat'               => :not_acceptable,
-      'ActionController::InvalidAuthenticityToken'    => :unprocessable_entity,
-      'ActionController::InvalidCrossOriginRequest'   => :unprocessable_entity,
-      'ActionDispatch::ParamsParser::ParseError'      => :bad_request,
-      'ActionController::BadRequest'                  => :bad_request,
-      'ActionController::ParameterMissing'            => :bad_request,
-      'Rack::Utils::ParameterTypeError'               => :bad_request,
-      'Rack::Utils::InvalidParameterError'            => :bad_request
+    cattr_accessor :rescue_responses, default: Hash.new(:internal_server_error).merge!(
+      "ActionController::RoutingError"               => :not_found,
+      "AbstractController::ActionNotFound"           => :not_found,
+      "ActionController::MethodNotAllowed"           => :method_not_allowed,
+      "ActionController::UnknownHttpMethod"          => :method_not_allowed,
+      "ActionController::NotImplemented"             => :not_implemented,
+      "ActionController::UnknownFormat"              => :not_acceptable,
+      "ActionController::InvalidAuthenticityToken"   => :unprocessable_entity,
+      "ActionController::InvalidCrossOriginRequest"  => :unprocessable_entity,
+      "ActionDispatch::Http::Parameters::ParseError" => :bad_request,
+      "ActionController::BadRequest"                 => :bad_request,
+      "ActionController::ParameterMissing"           => :bad_request,
+      "Rack::QueryParser::ParameterTypeError"        => :bad_request,
+      "Rack::QueryParser::InvalidParameterError"     => :bad_request
     )
 
-    cattr_accessor :rescue_templates
-    @@rescue_templates = Hash.new('diagnostics')
-    @@rescue_templates.merge!(
-      'ActionView::MissingTemplate'         => 'missing_template',
-      'ActionController::RoutingError'      => 'routing_error',
-      'AbstractController::ActionNotFound'  => 'unknown_action',
-      'ActionView::Template::Error'         => 'template_error'
+    cattr_accessor :rescue_templates, default: Hash.new("diagnostics").merge!(
+      "ActionView::MissingTemplate"         => "missing_template",
+      "ActionController::RoutingError"      => "routing_error",
+      "AbstractController::ActionNotFound"  => "unknown_action",
+      "ActionView::Template::Error"         => "template_error"
     )
 
     attr_reader :backtrace_cleaner, :exception, :line_number, :file
@@ -100,49 +98,49 @@ module ActionDispatch
 
     private
 
-    def backtrace
-      Array(@exception.backtrace)
-    end
+      def backtrace
+        Array(@exception.backtrace)
+      end
 
-    def original_exception(exception)
-      if @@rescue_responses.has_key?(exception.cause.class.name)
-        exception.cause
-      else
-        exception
+      def original_exception(exception)
+        if @@rescue_responses.has_key?(exception.cause.class.name)
+          exception.cause
+        else
+          exception
+        end
       end
-    end
 
-    def clean_backtrace(*args)
-      if backtrace_cleaner
-        backtrace_cleaner.clean(backtrace, *args)
-      else
-        backtrace
+      def clean_backtrace(*args)
+        if backtrace_cleaner
+          backtrace_cleaner.clean(backtrace, *args)
+        else
+          backtrace
+        end
       end
-    end
 
-    def source_fragment(path, line)
-      return unless Rails.respond_to?(:root) && Rails.root
-      full_path = Rails.root.join(path)
-      if File.exist?(full_path)
-        File.open(full_path, "r") do |file|
-          start = [line - 3, 0].max
-          lines = file.each_line.drop(start).take(6)
-          Hash[*(start+1..(lines.count+start)).zip(lines).flatten]
+      def source_fragment(path, line)
+        return unless Rails.respond_to?(:root) && Rails.root
+        full_path = Rails.root.join(path)
+        if File.exist?(full_path)
+          File.open(full_path, "r") do |file|
+            start = [line - 3, 0].max
+            lines = file.each_line.drop(start).take(6)
+            Hash[*(start + 1..(lines.count + start)).zip(lines).flatten]
+          end
         end
       end
-    end
 
-    def extract_file_and_line_number(trace)
-      # Split by the first colon followed by some digits, which works for both
-      # Windows and Unix path styles.
-      file, line = trace.match(/^(.+?):(\d+).*$/, &:captures) || trace
-      [file, line.to_i]
-    end
+      def extract_file_and_line_number(trace)
+        # Split by the first colon followed by some digits, which works for both
+        # Windows and Unix path styles.
+        file, line = trace.match(/^(.+?):(\d+).*$/, &:captures) || trace
+        [file, line.to_i]
+      end
 
-    def expand_backtrace
-      @exception.backtrace.unshift(
-        @exception.to_s.split("\n")
-      ).flatten!
-    end
+      def expand_backtrace
+        @exception.backtrace.unshift(
+          @exception.to_s.split("\n")
+        ).flatten!
+      end
   end
 end
diff --git a/actionpack/lib/action_dispatch/middleware/executor.rb b/actionpack/lib/action_dispatch/middleware/executor.rb
index 06245b403b..129b18d3d9 100644
--- a/actionpack/lib/action_dispatch/middleware/executor.rb
+++ b/actionpack/lib/action_dispatch/middleware/executor.rb
@@ -1,4 +1,6 @@
-require 'rack/body_proxy'
+# frozen_string_literal: true
+
+require "rack/body_proxy"
 
 module ActionDispatch
   class Executor
diff --git a/actionpack/lib/action_dispatch/middleware/flash.rb b/actionpack/lib/action_dispatch/middleware/flash.rb
index 80703940ed..3e11846778 100644
--- a/actionpack/lib/action_dispatch/middleware/flash.rb
+++ b/actionpack/lib/action_dispatch/middleware/flash.rb
@@ -1,4 +1,6 @@
-require 'active_support/core_ext/hash/keys'
+# frozen_string_literal: true
+
+require "active_support/core_ext/hash/keys"
 
 module ActionDispatch
   # The flash provides a way to pass temporary primitive-types (String, Array, Hash) between actions. Anything you place in the flash will be exposed
@@ -36,7 +38,7 @@ module ActionDispatch
   #
   # See docs on the FlashHash class for more details about the flash.
   class Flash
-    KEY = 'action_dispatch.request.flash_hash'.freeze
+    KEY = "action_dispatch.request.flash_hash".freeze
 
     module RequestMethods
       # Access the contents of the flash. Use <tt>flash["notice"]</tt> to
@@ -60,14 +62,14 @@ module ActionDispatch
         session    = self.session || {}
         flash_hash = self.flash_hash
 
-        if flash_hash && (flash_hash.present? || session.key?('flash'))
+        if flash_hash && (flash_hash.present? || session.key?("flash"))
           session["flash"] = flash_hash.to_session_value
           self.flash = flash_hash.dup
         end
 
-        if (!session.respond_to?(:loaded?) || session.loaded?) && # (reset_session uses {}, which doesn't implement #loaded?)
-            session.key?('flash') && session['flash'].nil?
-          session.delete('flash')
+        if (!session.respond_to?(:loaded?) || session.loaded?) && # reset_session uses {}, which doesn't implement #loaded?
+            session.key?("flash") && session["flash"].nil?
+          session.delete("flash")
         end
       end
 
@@ -118,8 +120,8 @@ module ActionDispatch
           end
           new(flashes, flashes.keys)
         when Hash # Rails 4.0
-          flashes = value['flashes']
-          if discard = value['discard']
+          flashes = value["flashes"]
+          if discard = value["discard"]
             flashes.except!(*discard)
           end
           new(flashes, flashes.keys)
@@ -129,11 +131,11 @@ module ActionDispatch
       end
 
       # Builds a hash containing the flashes to keep for the next request.
-      # If there are none to keep, returns nil.
+      # If there are none to keep, returns +nil+.
       def to_session_value #:nodoc:
         flashes_to_keep = @flashes.except(*@discard)
         return nil if flashes_to_keep.empty?
-        { 'discard' => [], 'flashes' => flashes_to_keep }
+        { "discard" => [], "flashes" => flashes_to_keep }
       end
 
       def initialize(flashes = {}, discard = []) #:nodoc:
@@ -277,15 +279,16 @@ module ActionDispatch
       end
 
       protected
-      def now_is_loaded?
-        @now
-      end
+        def now_is_loaded?
+          @now
+        end
 
-      def stringify_array(array)
-        array.map do |item|
-          item.kind_of?(Symbol) ? item.to_s : item
+      private
+        def stringify_array(array) # :doc:
+          array.map do |item|
+            item.kind_of?(Symbol) ? item.to_s : item
+          end
         end
-      end
     end
 
     def self.new(app) app; end
diff --git a/actionpack/lib/action_dispatch/middleware/params_parser.rb b/actionpack/lib/action_dispatch/middleware/params_parser.rb
deleted file mode 100644
index faf3262b8f..0000000000
--- a/actionpack/lib/action_dispatch/middleware/params_parser.rb
+++ /dev/null
@@ -1,46 +0,0 @@
-require 'action_dispatch/http/request'
-
-module ActionDispatch
-  # ActionDispatch::ParamsParser works for all the requests having any Content-Length
-  # (like POST). It takes raw data from the request and puts it through the parser
-  # that is picked based on Content-Type header.
-  #
-  # In case of any error while parsing data ParamsParser::ParseError is raised.
-  class ParamsParser
-    # Raised when raw data from the request cannot be parsed by the parser
-    # defined for request's content mime type.
-    class ParseError < StandardError
-
-      def initialize(message = nil, original_exception = nil)
-        if message
-          ActiveSupport::Deprecation.warn("Passing #message is deprecated and has no effect. " \
-                                          "#{self.class} will automatically capture the message " \
-                                          "of the original exception.", caller)
-        end
-
-        if original_exception
-          ActiveSupport::Deprecation.warn("Passing #original_exception is deprecated and has no effect. " \
-                                          "Exceptions will automatically capture the original exception.", caller)
-        end
-
-        super($!.message)
-      end
-
-      def original_exception
-        ActiveSupport::Deprecation.warn("#original_exception is deprecated. Use #cause instead.", caller)
-        cause
-      end
-    end
-
-    # Create a new +ParamsParser+ middleware instance.
-    #
-    # The +parsers+ argument can take Hash of parsers where key is identifying
-    # content mime type, and value is a lambda that is going to process data.
-    def self.new(app, parsers = {})
-      ActiveSupport::Deprecation.warn('ActionDispatch::ParamsParser is deprecated and will be removed in Rails 5.1. Configure the parameter parsing in ActionDispatch::Request.parameter_parsers.')
-      parsers = parsers.transform_keys { |key| key.respond_to?(:symbol) ? key.symbol : key }
-      ActionDispatch::Request.parameter_parsers = ActionDispatch::Request::DEFAULT_PARSERS.merge(parsers)
-      app
-    end
-  end
-end
diff --git a/actionpack/lib/action_dispatch/middleware/public_exceptions.rb b/actionpack/lib/action_dispatch/middleware/public_exceptions.rb
index 0f27984550..3feb3a19f3 100644
--- a/actionpack/lib/action_dispatch/middleware/public_exceptions.rb
+++ b/actionpack/lib/action_dispatch/middleware/public_exceptions.rb
@@ -1,11 +1,13 @@
+# frozen_string_literal: true
+
 module ActionDispatch
   # When called, this middleware renders an error page. By default if an HTML
-  # response is expected it will render static error pages from the `/public`
+  # response is expected it will render static error pages from the <tt>/public</tt>
   # directory. For example when this middleware receives a 500 response it will
-  # render the template found in `/public/500.html`.
+  # render the template found in <tt>/public/500.html</tt>.
   # If an internationalized locale is set, this middleware will attempt to render
-  # the template in `/public/500.<locale>.html`. If an internationalized template
-  # is not found it will fall back on `/public/500.html`.
+  # the template in <tt>/public/500.<locale>.html</tt>. If an internationalized template
+  # is not found it will fall back on <tt>/public/500.html</tt>.
   #
   # When a request with a content type other than HTML is made, this middleware
   # will attempt to convert error information into the appropriate response type.
@@ -20,36 +22,36 @@ module ActionDispatch
       request      = ActionDispatch::Request.new(env)
       status       = request.path_info[1..-1].to_i
       content_type = request.formats.first
-      body         = { :status => status, :error => Rack::Utils::HTTP_STATUS_CODES.fetch(status, Rack::Utils::HTTP_STATUS_CODES[500]) }
+      body         = { status: status, error: Rack::Utils::HTTP_STATUS_CODES.fetch(status, Rack::Utils::HTTP_STATUS_CODES[500]) }
 
       render(status, content_type, body)
     end
 
     private
 
-    def render(status, content_type, body)
-      format = "to_#{content_type.to_sym}" if content_type
-      if format && body.respond_to?(format)
-        render_format(status, content_type, body.public_send(format))
-      else
-        render_html(status)
+      def render(status, content_type, body)
+        format = "to_#{content_type.to_sym}" if content_type
+        if format && body.respond_to?(format)
+          render_format(status, content_type, body.public_send(format))
+        else
+          render_html(status)
+        end
       end
-    end
 
-    def render_format(status, content_type, body)
-      [status, {'Content-Type' => "#{content_type}; charset=#{ActionDispatch::Response.default_charset}",
-                'Content-Length' => body.bytesize.to_s}, [body]]
-    end
+      def render_format(status, content_type, body)
+        [status, { "Content-Type" => "#{content_type}; charset=#{ActionDispatch::Response.default_charset}",
+                  "Content-Length" => body.bytesize.to_s }, [body]]
+      end
 
-    def render_html(status)
-      path = "#{public_path}/#{status}.#{I18n.locale}.html"
-      path = "#{public_path}/#{status}.html" unless (found = File.exist?(path))
+      def render_html(status)
+        path = "#{public_path}/#{status}.#{I18n.locale}.html"
+        path = "#{public_path}/#{status}.html" unless (found = File.exist?(path))
 
-      if found || File.exist?(path)
-        render_format(status, 'text/html', File.read(path))
-      else
-        [404, { "X-Cascade" => "pass" }, []]
+        if found || File.exist?(path)
+          render_format(status, "text/html", File.read(path))
+        else
+          [404, { "X-Cascade" => "pass" }, []]
+        end
       end
-    end
   end
 end
diff --git a/actionpack/lib/action_dispatch/middleware/reloader.rb b/actionpack/lib/action_dispatch/middleware/reloader.rb
index 112bde6596..8bb3ba7504 100644
--- a/actionpack/lib/action_dispatch/middleware/reloader.rb
+++ b/actionpack/lib/action_dispatch/middleware/reloader.rb
@@ -1,54 +1,12 @@
+# frozen_string_literal: true
+
 module ActionDispatch
-  # ActionDispatch::Reloader provides prepare and cleanup callbacks,
-  # intended to assist with code reloading during development.
-  #
-  # Prepare callbacks are run before each request, and cleanup callbacks
-  # after each request. In this respect they are analogs of ActionDispatch::Callback's
-  # before and after callbacks. However, cleanup callbacks are not called until the
-  # request is fully complete -- that is, after #close has been called on
-  # the response body. This is important for streaming responses such as the
-  # following:
-  #
-  #     self.response_body = -> (response, output) do
-  #       # code here which refers to application models
-  #     end
-  #
-  # Cleanup callbacks will not be called until after the response_body lambda
-  # is evaluated, ensuring that it can refer to application models and other
-  # classes before they are unloaded.
+  # ActionDispatch::Reloader wraps the request with callbacks provided by ActiveSupport::Reloader
+  # callbacks, intended to assist with code reloading during development.
   #
   # By default, ActionDispatch::Reloader is included in the middleware stack
   # only in the development environment; specifically, when +config.cache_classes+
-  # is false. Callbacks may be registered even when it is not included in the
-  # middleware stack, but are executed only when <tt>ActionDispatch::Reloader.prepare!</tt>
-  # or <tt>ActionDispatch::Reloader.cleanup!</tt> are called manually.
-  #
+  # is false.
   class Reloader < Executor
-    def self.to_prepare(*args, &block)
-      ActiveSupport::Reloader.to_prepare(*args, &block)
-    end
-
-    def self.to_cleanup(*args, &block)
-      ActiveSupport::Reloader.to_complete(*args, &block)
-    end
-
-    def self.prepare!
-      default_reloader.prepare!
-    end
-
-    def self.cleanup!
-      default_reloader.reload!
-    end
-
-    class << self
-      attr_accessor :default_reloader # :nodoc:
-
-      deprecate to_prepare: 'use ActiveSupport::Reloader.to_prepare instead',
-        to_cleanup: 'use ActiveSupport::Reloader.to_complete instead',
-        prepare!: 'use Rails.application.reloader.prepare! instead',
-        cleanup!: 'use Rails.application.reloader.reload! instead of cleanup + prepare'
-    end
-
-    self.default_reloader = ActiveSupport::Reloader
   end
 end
diff --git a/actionpack/lib/action_dispatch/middleware/remote_ip.rb b/actionpack/lib/action_dispatch/middleware/remote_ip.rb
index 31b75498b6..35158f9062 100644
--- a/actionpack/lib/action_dispatch/middleware/remote_ip.rb
+++ b/actionpack/lib/action_dispatch/middleware/remote_ip.rb
@@ -1,4 +1,6 @@
-require 'ipaddr'
+# frozen_string_literal: true
+
+require "ipaddr"
 
 module ActionDispatch
   # This middleware calculates the IP address of the remote client that is
@@ -10,7 +12,7 @@ module ActionDispatch
   # by @gingerlime. A more detailed explanation of the algorithm is given
   # at GetIp#calculate_ip.
   #
-  # Some Rack servers concatenate repeated headers, like {HTTP RFC 2616}[http://www.w3.org/Protocols/rfc2616/rfc2616-sec4.html#sec4.2]
+  # Some Rack servers concatenate repeated headers, like {HTTP RFC 2616}[https://www.w3.org/Protocols/rfc2616/rfc2616-sec4.html#sec4.2]
   # requires. Some Rack servers simply drop preceding headers, and only report
   # the value that was {given in the last header}[http://andre.arko.net/2011/12/26/repeated-headers-and-ruby-web-servers].
   # If you are behind multiple proxy servers (like NGINX to HAProxy to Unicorn)
@@ -29,7 +31,7 @@ module ActionDispatch
     # The default trusted IPs list simply includes IP addresses that are
     # guaranteed by the IP specification to be private addresses. Those will
     # not be the ultimate client IP in production, and so are discarded. See
-    # http://en.wikipedia.org/wiki/Private_network for details.
+    # https://en.wikipedia.org/wiki/Private_network for details.
     TRUSTED_PROXIES = [
       "127.0.0.1",      # localhost IPv4
       "::1",            # localhost IPv6
@@ -131,8 +133,8 @@ module ActionDispatch
         should_check_ip = @check_ip && client_ips.last && forwarded_ips.last
         if should_check_ip && !forwarded_ips.include?(client_ips.last)
           # We don't know which came from the proxy, and which from the user
-          raise IpSpoofAttackError, "IP spoofing attack?! " +
-            "HTTP_CLIENT_IP=#{@req.client_ip.inspect} " +
+          raise IpSpoofAttackError, "IP spoofing attack?! " \
+            "HTTP_CLIENT_IP=#{@req.client_ip.inspect} " \
             "HTTP_X_FORWARDED_FOR=#{@req.x_forwarded_for.inspect}"
         end
 
@@ -153,17 +155,17 @@ module ActionDispatch
         @ip ||= calculate_ip
       end
 
-    protected
+    private
 
-      def ips_from(header)
+      def ips_from(header) # :doc:
         return [] unless header
-        # Split the comma-separated list into an array of strings
+        # Split the comma-separated list into an array of strings.
         ips = header.strip.split(/[,\s]+/)
         ips.select do |ip|
           begin
-            # Only return IPs that are valid according to the IPAddr#new method
+            # Only return IPs that are valid according to the IPAddr#new method.
             range = IPAddr.new(ip).to_range
-            # we want to make sure nobody is sneaking a netmask in
+            # We want to make sure nobody is sneaking a netmask in.
             range.begin == range.end
           rescue ArgumentError
             nil
@@ -171,13 +173,11 @@ module ActionDispatch
         end
       end
 
-      def filter_proxies(ips)
+      def filter_proxies(ips) # :doc:
         ips.reject do |ip|
           @proxies.any? { |proxy| proxy === ip }
         end
       end
-
     end
-
   end
 end
diff --git a/actionpack/lib/action_dispatch/middleware/request_id.rb b/actionpack/lib/action_dispatch/middleware/request_id.rb
index 1555ff72af..805d3f2148 100644
--- a/actionpack/lib/action_dispatch/middleware/request_id.rb
+++ b/actionpack/lib/action_dispatch/middleware/request_id.rb
@@ -1,9 +1,12 @@
-require 'securerandom'
-require 'active_support/core_ext/string/access'
+# frozen_string_literal: true
+
+require "securerandom"
+require "active_support/core_ext/string/access"
 
 module ActionDispatch
-  # Makes a unique request id available to the action_dispatch.request_id env variable (which is then accessible through
-  # ActionDispatch::Request#uuid or the alias ActionDispatch::Request#request_id) and sends the same id to the client via the X-Request-Id header.
+  # Makes a unique request id available to the +action_dispatch.request_id+ env variable (which is then accessible
+  # through <tt>ActionDispatch::Request#request_id</tt> or the alias <tt>ActionDispatch::Request#uuid</tt>) and sends
+  # the same id to the client via the X-Request-Id header.
   #
   # The unique request id is either based on the X-Request-Id header in the request, which would typically be generated
   # by a firewall, load balancer, or the web server, or, if this header is not available, a random uuid. If the
@@ -12,7 +15,7 @@ module ActionDispatch
   # The unique request id can be used to trace a request end-to-end and would typically end up being part of log files
   # from multiple pieces of the stack.
   class RequestId
-    X_REQUEST_ID = "X-Request-Id".freeze # :nodoc:
+    X_REQUEST_ID = "X-Request-Id".freeze #:nodoc:
 
     def initialize(app)
       @app = app
diff --git a/actionpack/lib/action_dispatch/middleware/session/abstract_store.rb b/actionpack/lib/action_dispatch/middleware/session/abstract_store.rb
index 5fb5953811..5b0be96223 100644
--- a/actionpack/lib/action_dispatch/middleware/session/abstract_store.rb
+++ b/actionpack/lib/action_dispatch/middleware/session/abstract_store.rb
@@ -1,34 +1,25 @@
-require 'rack/utils'
-require 'rack/request'
-require 'rack/session/abstract/id'
-require 'action_dispatch/middleware/cookies'
-require 'action_dispatch/request/session'
+# frozen_string_literal: true
+
+require "rack/utils"
+require "rack/request"
+require "rack/session/abstract/id"
+require "action_dispatch/middleware/cookies"
+require "action_dispatch/request/session"
 
 module ActionDispatch
   module Session
     class SessionRestoreError < StandardError #:nodoc:
-
-      def initialize(const_error = nil)
-        if const_error
-          ActiveSupport::Deprecation.warn("Passing #original_exception is deprecated and has no effect. " \
-                                          "Exceptions will automatically capture the original exception.", caller)
-        end
-
-        super("Session contains objects whose class definition isn't available.\n" +
-          "Remember to require the classes for all objects kept in the session.\n" +
+      def initialize
+        super("Session contains objects whose class definition isn't available.\n" \
+          "Remember to require the classes for all objects kept in the session.\n" \
           "(Original exception: #{$!.message} [#{$!.class}])\n")
         set_backtrace $!.backtrace
       end
-
-      def original_exception
-        ActiveSupport::Deprecation.warn("#original_exception is deprecated. Use #cause instead.", caller)
-        cause
-      end
     end
 
     module Compatibility
       def initialize(app, options = {})
-        options[:key] ||= '_session_id'
+        options[:key] ||= "_session_id"
         super
       end
 
@@ -38,14 +29,13 @@ module ActionDispatch
         sid
       end
 
-    protected
+    private
 
-      def initialize_sid
+      def initialize_sid # :doc:
         @default_options.delete(:sidbits)
         @default_options.delete(:secure_random)
       end
 
-      private
       def make_request(env)
         ActionDispatch::Request.new env
       end
@@ -65,7 +55,7 @@ module ActionDispatch
       rescue ArgumentError => argument_error
         if argument_error.message =~ %r{undefined class/module ([\w:]*\w)}
           begin
-            # Note that the regexp does not allow $1 to end with a ':'
+            # Note that the regexp does not allow $1 to end with a ':'.
             $1.constantize
           rescue LoadError, NameError
             raise ActionDispatch::Session::SessionRestoreError
@@ -94,9 +84,9 @@ module ActionDispatch
 
       private
 
-      def set_cookie(request, session_id, cookie)
-        request.cookie_jar[key] = cookie
-      end
+        def set_cookie(request, session_id, cookie)
+          request.cookie_jar[key] = cookie
+        end
     end
   end
 end
diff --git a/actionpack/lib/action_dispatch/middleware/session/cache_store.rb b/actionpack/lib/action_dispatch/middleware/session/cache_store.rb
index 589ae46e38..a6d965a644 100644
--- a/actionpack/lib/action_dispatch/middleware/session/cache_store.rb
+++ b/actionpack/lib/action_dispatch/middleware/session/cache_store.rb
@@ -1,4 +1,6 @@
-require 'action_dispatch/middleware/session/abstract_store'
+# frozen_string_literal: true
+
+require "action_dispatch/middleware/session/abstract_store"
 
 module ActionDispatch
   module Session
@@ -19,7 +21,7 @@ module ActionDispatch
 
       # Get a session from the cache.
       def find_session(env, sid)
-        unless sid and session = @cache.read(cache_key(sid))
+        unless sid && (session = @cache.read(cache_key(sid)))
           sid, session = generate_sid, {}
         end
         [sid, session]
@@ -29,7 +31,7 @@ module ActionDispatch
       def write_session(env, sid, session, options)
         key = cache_key(sid)
         if session
-          @cache.write(key, session, :expires_in => options[:expire_after])
+          @cache.write(key, session, expires_in: options[:expire_after])
         else
           @cache.delete(key)
         end
diff --git a/actionpack/lib/action_dispatch/middleware/session/cookie_store.rb b/actionpack/lib/action_dispatch/middleware/session/cookie_store.rb
index dec9c60ef2..4ea96196d3 100644
--- a/actionpack/lib/action_dispatch/middleware/session/cookie_store.rb
+++ b/actionpack/lib/action_dispatch/middleware/session/cookie_store.rb
@@ -1,6 +1,8 @@
-require 'active_support/core_ext/hash/keys'
-require 'action_dispatch/middleware/session/abstract_store'
-require 'rack/session/cookie'
+# frozen_string_literal: true
+
+require "active_support/core_ext/hash/keys"
+require "action_dispatch/middleware/session/abstract_store"
+require "rack/session/cookie"
 
 module ActionDispatch
   module Session
@@ -19,39 +21,25 @@ module ActionDispatch
     # knowing your app's secret key, but can easily read their +user_id+. This
     # was the default for Rails 3 apps.
     #
-    # If you have secret_key_base set, your cookies will be encrypted. This
+    # Your cookies will be encrypted using your apps secret_key_base. This
     # goes a step further than signed cookies in that encrypted cookies cannot
     # be altered or read by users. This is the default starting in Rails 4.
     #
-    # If you have both secret_token and secret_key_base set, your cookies will
-    # be encrypted, and signed cookies generated by Rails 3 will be
-    # transparently read and encrypted to provide a smooth upgrade path.
-    #
-    # Configure your session store in config/initializers/session_store.rb:
+    # Configure your session store in <tt>config/initializers/session_store.rb</tt>:
     #
     #   Rails.application.config.session_store :cookie_store, key: '_your_app_session'
     #
-    # Configure your secret key in config/secrets.yml:
-    #
-    #   development:
-    #     secret_key_base: 'secret key'
+    # By default, your secret key base is derived from your application name in
+    # the test and development environments. In all other environments, it is stored
+    # encrypted in the <tt>config/credentials.yml.enc</tt> file.
     #
-    # To generate a secret key for an existing application, run `rails secret`.
+    # If your application was not updated to Rails 5.2 defaults, the secret_key_base
+    # will be found in the old <tt>config/secrets.yml</tt> file.
     #
-    # If you are upgrading an existing Rails 3 app, you should leave your
-    # existing secret_token in place and simply add the new secret_key_base.
-    # Note that you should wait to set secret_key_base until you have 100% of
-    # your userbase on Rails 4 and are reasonably sure you will not need to
-    # rollback to Rails 3. This is because cookies signed based on the new
-    # secret_key_base in Rails 4 are not backwards compatible with Rails 3.
-    # You are free to leave your existing secret_token in place, not set the
-    # new secret_key_base, and ignore the deprecation warnings until you are
-    # reasonably sure that your upgrade is otherwise complete. Additionally,
-    # you should take care to make sure you are not relying on the ability to
-    # decode signed cookies generated by your app in external applications or
-    # JavaScript before upgrading.
-    #
-    # Note that changing the secret key will invalidate all existing sessions!
+    # Note that changing your secret_key_base will invalidate all existing session.
+    # Additionally, you should take care to make sure you are not relying on the
+    # ability to decode signed cookies generated by your app in external
+    # applications or JavaScript before changing it.
     #
     # Because CookieStore extends Rack::Session::Abstract::Persisted, many of the
     # options described there can be used to customize the session cookie that
@@ -63,8 +51,8 @@ module ActionDispatch
     # Other useful options include <tt>:key</tt>, <tt>:secure</tt> and
     # <tt>:httponly</tt>.
     class CookieStore < AbstractStore
-      def initialize(app, options={})
-        super(app, options.merge!(:cookie_only => true))
+      def initialize(app, options = {})
+        super(app, options.merge!(cookie_only: true))
       end
 
       def delete_session(req, session_id, options)
@@ -84,46 +72,46 @@ module ActionDispatch
 
       private
 
-      def extract_session_id(req)
-        stale_session_check! do
-          unpacked_cookie_data(req)["session_id"]
+        def extract_session_id(req)
+          stale_session_check! do
+            unpacked_cookie_data(req)["session_id"]
+          end
         end
-      end
 
-      def unpacked_cookie_data(req)
-        req.fetch_header("action_dispatch.request.unsigned_session_cookie") do |k|
-          v = stale_session_check! do
-            if data = get_cookie(req)
-              data.stringify_keys!
+        def unpacked_cookie_data(req)
+          req.fetch_header("action_dispatch.request.unsigned_session_cookie") do |k|
+            v = stale_session_check! do
+              if data = get_cookie(req)
+                data.stringify_keys!
+              end
+              data || {}
             end
-            data || {}
+            req.set_header k, v
           end
-          req.set_header k, v
         end
-      end
 
-      def persistent_session_id!(data, sid=nil)
-        data ||= {}
-        data["session_id"] ||= sid || generate_sid
-        data
-      end
+        def persistent_session_id!(data, sid = nil)
+          data ||= {}
+          data["session_id"] ||= sid || generate_sid
+          data
+        end
 
-      def write_session(req, sid, session_data, options)
-        session_data["session_id"] = sid
-        session_data
-      end
+        def write_session(req, sid, session_data, options)
+          session_data["session_id"] = sid
+          session_data
+        end
 
-      def set_cookie(request, session_id, cookie)
-        cookie_jar(request)[@key] = cookie
-      end
+        def set_cookie(request, session_id, cookie)
+          cookie_jar(request)[@key] = cookie
+        end
 
-      def get_cookie(req)
-        cookie_jar(req)[@key]
-      end
+        def get_cookie(req)
+          cookie_jar(req)[@key]
+        end
 
-      def cookie_jar(request)
-        request.cookie_jar.signed_or_encrypted
-      end
+        def cookie_jar(request)
+          request.cookie_jar.signed_or_encrypted
+        end
     end
   end
 end
diff --git a/actionpack/lib/action_dispatch/middleware/session/mem_cache_store.rb b/actionpack/lib/action_dispatch/middleware/session/mem_cache_store.rb
index cb19786f0b..914df3a2b1 100644
--- a/actionpack/lib/action_dispatch/middleware/session/mem_cache_store.rb
+++ b/actionpack/lib/action_dispatch/middleware/session/mem_cache_store.rb
@@ -1,6 +1,8 @@
-require 'action_dispatch/middleware/session/abstract_store'
+# frozen_string_literal: true
+
+require "action_dispatch/middleware/session/abstract_store"
 begin
-  require 'rack/session/dalli'
+  require "rack/session/dalli"
 rescue LoadError => e
   $stderr.puts "You don't have dalli installed in your application. Please add it to your Gemfile and run bundle install"
   raise e
diff --git a/actionpack/lib/action_dispatch/middleware/show_exceptions.rb b/actionpack/lib/action_dispatch/middleware/show_exceptions.rb
index 64695f9738..3c88afd4d3 100644
--- a/actionpack/lib/action_dispatch/middleware/show_exceptions.rb
+++ b/actionpack/lib/action_dispatch/middleware/show_exceptions.rb
@@ -1,5 +1,7 @@
-require 'action_dispatch/http/request'
-require 'action_dispatch/middleware/exception_wrapper'
+# frozen_string_literal: true
+
+require "action_dispatch/http/request"
+require "action_dispatch/middleware/exception_wrapper"
 
 module ActionDispatch
   # This middleware rescues any exception returned by the application
@@ -8,14 +10,14 @@ module ActionDispatch
   # The exceptions app should be passed as parameter on initialization
   # of ShowExceptions. Every time there is an exception, ShowExceptions will
   # store the exception in env["action_dispatch.exception"], rewrite the
-  # PATH_INFO to the exception status code and call the rack app.
+  # PATH_INFO to the exception status code and call the Rack app.
   #
   # If the application returns a "X-Cascade" pass response, this middleware
   # will send an empty response as result with the correct status code.
   # If any exception happens inside the exceptions app, this middleware
   # catches the exceptions and returns a FAILSAFE_RESPONSE.
   class ShowExceptions
-    FAILSAFE_RESPONSE = [500, { 'Content-Type' => 'text/plain' },
+    FAILSAFE_RESPONSE = [500, { "Content-Type" => "text/plain" },
       ["500 Internal Server Error\n" \
        "If you are the administrator of this website, then please read this web " \
        "application's log file and/or the web server's log file to find out what " \
@@ -39,22 +41,22 @@ module ActionDispatch
 
     private
 
-    def render_exception(request, exception)
-      backtrace_cleaner = request.get_header 'action_dispatch.backtrace_cleaner'
-      wrapper = ExceptionWrapper.new(backtrace_cleaner, exception)
-      status  = wrapper.status_code
-      request.set_header "action_dispatch.exception", wrapper.exception
-      request.set_header "action_dispatch.original_path", request.path_info
-      request.path_info = "/#{status}"
-      response = @exceptions_app.call(request.env)
-      response[1]['X-Cascade'] == 'pass' ? pass_response(status) : response
-    rescue Exception => failsafe_error
-      $stderr.puts "Error during failsafe response: #{failsafe_error}\n  #{failsafe_error.backtrace * "\n  "}"
-      FAILSAFE_RESPONSE
-    end
+      def render_exception(request, exception)
+        backtrace_cleaner = request.get_header "action_dispatch.backtrace_cleaner"
+        wrapper = ExceptionWrapper.new(backtrace_cleaner, exception)
+        status  = wrapper.status_code
+        request.set_header "action_dispatch.exception", wrapper.exception
+        request.set_header "action_dispatch.original_path", request.path_info
+        request.path_info = "/#{status}"
+        response = @exceptions_app.call(request.env)
+        response[1]["X-Cascade"] == "pass" ? pass_response(status) : response
+      rescue Exception => failsafe_error
+        $stderr.puts "Error during failsafe response: #{failsafe_error}\n  #{failsafe_error.backtrace * "\n  "}"
+        FAILSAFE_RESPONSE
+      end
 
-    def pass_response(status)
-      [status, {"Content-Type" => "text/html; charset=#{Response.default_charset}", "Content-Length" => "0"}, []]
-    end
+      def pass_response(status)
+        [status, { "Content-Type" => "text/html; charset=#{Response.default_charset}", "Content-Length" => "0" }, []]
+      end
   end
 end
diff --git a/actionpack/lib/action_dispatch/middleware/ssl.rb b/actionpack/lib/action_dispatch/middleware/ssl.rb
index ab3077b308..ef633aadc6 100644
--- a/actionpack/lib/action_dispatch/middleware/ssl.rb
+++ b/actionpack/lib/action_dispatch/middleware/ssl.rb
@@ -1,78 +1,68 @@
+# frozen_string_literal: true
+
 module ActionDispatch
-  # This middleware is added to the stack when `config.force_ssl = true`, and is passed
-  # the options set in `config.ssl_options`. It does three jobs to enforce secure HTTP
+  # This middleware is added to the stack when <tt>config.force_ssl = true</tt>, and is passed
+  # the options set in +config.ssl_options+. It does three jobs to enforce secure HTTP
   # requests:
   #
-  #   1. TLS redirect: Permanently redirects http:// requests to https://
-  #      with the same URL host, path, etc. Enabled by default. Set `config.ssl_options`
-  #      to modify the destination URL
-  #      (e.g. `redirect: { host: "secure.widgets.com", port: 8080 }`), or set
-  #      `redirect: false` to disable this feature.
+  # 1. <b>TLS redirect</b>: Permanently redirects +http://+ requests to +https://+
+  #    with the same URL host, path, etc. Enabled by default. Set +config.ssl_options+
+  #    to modify the destination URL
+  #    (e.g. <tt>redirect: { host: "secure.widgets.com", port: 8080 }</tt>), or set
+  #    <tt>redirect: false</tt> to disable this feature.
+  #
+  #    Requests can opt-out of redirection with +exclude+:
+  #
+  #      config.ssl_options = { redirect: { exclude: -> request { request.path =~ /healthcheck/ } } }
+  #
+  # 2. <b>Secure cookies</b>: Sets the +secure+ flag on cookies to tell browsers they
+  #    must not be sent along with +http://+ requests. Enabled by default. Set
+  #    +config.ssl_options+ with <tt>secure_cookies: false</tt> to disable this feature.
   #
-  #   2. Secure cookies: Sets the `secure` flag on cookies to tell browsers they
-  #      mustn't be sent along with http:// requests. Enabled by default. Set
-  #      `config.ssl_options` with `secure_cookies: false` to disable this feature.
+  # 3. <b>HTTP Strict Transport Security (HSTS)</b>: Tells the browser to remember
+  #    this site as TLS-only and automatically redirect non-TLS requests.
+  #    Enabled by default. Configure +config.ssl_options+ with <tt>hsts: false</tt> to disable.
   #
-  #   3. HTTP Strict Transport Security (HSTS): Tells the browser to remember
-  #      this site as TLS-only and automatically redirect non-TLS requests.
-  #      Enabled by default. Configure `config.ssl_options` with `hsts: false` to disable.
+  #    Set +config.ssl_options+ with <tt>hsts: { ... }</tt> to configure HSTS:
   #
-  # Set `config.ssl_options` with `hsts: { … }` to configure HSTS:
-  #   * `expires`: How long, in seconds, these settings will stick. Defaults to
-  #     `180.days` (recommended). The minimum required to qualify for browser
-  #     preload lists is `18.weeks`.
-  #   * `subdomains`: Set to `true` to tell the browser to apply these settings
-  #     to all subdomains. This protects your cookies from interception by a
-  #     vulnerable site on a subdomain. Defaults to `true`.
-  #   * `preload`: Advertise that this site may be included in browsers'
-  #     preloaded HSTS lists. HSTS protects your site on every visit *except the
-  #     first visit* since it hasn't seen your HSTS header yet. To close this
-  #     gap, browser vendors include a baked-in list of HSTS-enabled sites.
-  #     Go to https://hstspreload.appspot.com to submit your site for inclusion.
+  #    * +expires+: How long, in seconds, these settings will stick. The minimum
+  #      required to qualify for browser preload lists is 18 weeks. Defaults to
+  #      180 days (recommended).
   #
-  # To turn off HSTS, omitting the header is not enough. Browsers will remember the
-  # original HSTS directive until it expires. Instead, use the header to tell browsers to
-  # expire HSTS immediately. Setting `hsts: false` is a shortcut for
-  # `hsts: { expires: 0 }`.
+  #    * +subdomains+: Set to +true+ to tell the browser to apply these settings
+  #      to all subdomains. This protects your cookies from interception by a
+  #      vulnerable site on a subdomain. Defaults to +true+.
   #
-  # Requests can opt-out of redirection with `exclude`:
+  #    * +preload+: Advertise that this site may be included in browsers'
+  #      preloaded HSTS lists. HSTS protects your site on every visit <i>except the
+  #      first visit</i> since it hasn't seen your HSTS header yet. To close this
+  #      gap, browser vendors include a baked-in list of HSTS-enabled sites.
+  #      Go to https://hstspreload.org to submit your site for inclusion.
+  #      Defaults to +false+.
   #
-  #    config.ssl_options = { redirect: { exclude: -> request { request.path =~ /healthcheck/ } } }
+  #    To turn off HSTS, omitting the header is not enough. Browsers will remember the
+  #    original HSTS directive until it expires. Instead, use the header to tell browsers to
+  #    expire HSTS immediately. Setting <tt>hsts: false</tt> is a shortcut for
+  #    <tt>hsts: { expires: 0 }</tt>.
   class SSL
+    # :stopdoc:
+
     # Default to 180 days, the low end for https://www.ssllabs.com/ssltest/
     # and greater than the 18-week requirement for browser preload lists.
     HSTS_EXPIRES_IN = 15552000
 
     def self.default_hsts_options
-      { expires: HSTS_EXPIRES_IN, subdomains: false, preload: false }
+      { expires: HSTS_EXPIRES_IN, subdomains: true, preload: false }
     end
 
-    def initialize(app, redirect: {}, hsts: {}, secure_cookies: true, **options)
+    def initialize(app, redirect: {}, hsts: {}, secure_cookies: true)
       @app = app
 
-      if options[:host] || options[:port]
-        ActiveSupport::Deprecation.warn <<-end_warning.strip_heredoc
-          The `:host` and `:port` options are moving within `:redirect`:
-          `config.ssl_options = { redirect: { host: …, port: … } }`.
-        end_warning
-        @redirect = options.slice(:host, :port)
-      else
-        @redirect = redirect
-      end
+      @redirect = redirect
 
       @exclude = @redirect && @redirect[:exclude] || proc { !@redirect }
       @secure_cookies = secure_cookies
 
-      if hsts != true && hsts != false && hsts[:subdomains].nil?
-        hsts[:subdomains] = false
-
-        ActiveSupport::Deprecation.warn <<-end_warning.strip_heredoc
-          In Rails 5.1, The `:subdomains` option of HSTS config will be treated as true if
-          unspecified. Set `config.ssl_options = { hsts: { subdomains: false } }` to opt out
-          of this behavior.
-        end_warning
-      end
-
       @hsts_header = build_hsts_header(normalize_hsts_options(hsts))
     end
 
@@ -92,7 +82,7 @@ module ActionDispatch
 
     private
       def set_hsts_header!(headers)
-        headers['Strict-Transport-Security'.freeze] ||= @hsts_header
+        headers["Strict-Transport-Security".freeze] ||= @hsts_header
       end
 
       def normalize_hsts_options(options)
@@ -109,19 +99,19 @@ module ActionDispatch
         end
       end
 
-      # http://tools.ietf.org/html/rfc6797#section-6.1
+      # https://tools.ietf.org/html/rfc6797#section-6.1
       def build_hsts_header(hsts)
-        value = "max-age=#{hsts[:expires].to_i}"
+        value = "max-age=#{hsts[:expires].to_i}".dup
         value << "; includeSubDomains" if hsts[:subdomains]
         value << "; preload" if hsts[:preload]
         value
       end
 
       def flag_cookies_as_secure!(headers)
-        if cookies = headers['Set-Cookie'.freeze]
+        if cookies = headers["Set-Cookie".freeze]
           cookies = cookies.split("\n".freeze)
 
-          headers['Set-Cookie'.freeze] = cookies.map { |cookie|
+          headers["Set-Cookie".freeze] = cookies.map { |cookie|
             if cookie !~ /;\s*secure\s*(;|$)/i
               "#{cookie}; secure"
             else
@@ -132,17 +122,25 @@ module ActionDispatch
       end
 
       def redirect_to_https(request)
-        [ @redirect.fetch(:status, 301),
-          { 'Content-Type' => 'text/html',
-            'Location' => https_location_for(request) },
+        [ @redirect.fetch(:status, redirection_status(request)),
+          { "Content-Type" => "text/html",
+            "Location" => https_location_for(request) },
           @redirect.fetch(:body, []) ]
       end
 
+      def redirection_status(request)
+        if request.get? || request.head?
+          301 # Issue a permanent redirect via a GET request.
+        else
+          307 # Issue a fresh request redirect to preserve the HTTP method.
+        end
+      end
+
       def https_location_for(request)
         host = @redirect[:host] || request.host
         port = @redirect[:port] || request.port
 
-        location = "https://#{host}"
+        location = "https://#{host}".dup
         location << ":#{port}" if port != 80 && port != 443
         location << request.fullpath
         location
diff --git a/actionpack/lib/action_dispatch/middleware/stack.rb b/actionpack/lib/action_dispatch/middleware/stack.rb
index 0b4bee5462..b82f8aa3a3 100644
--- a/actionpack/lib/action_dispatch/middleware/stack.rb
+++ b/actionpack/lib/action_dispatch/middleware/stack.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require "active_support/inflector/methods"
 require "active_support/dependencies"
 
@@ -88,7 +90,6 @@ module ActionDispatch
     end
 
     def delete(target)
-      target = get_class target
       middlewares.delete_if { |m| m.klass == target }
     end
 
@@ -102,32 +103,14 @@ module ActionDispatch
 
     private
 
-    def assert_index(index, where)
-      index = get_class index
-      i = index.is_a?(Integer) ? index : middlewares.index { |m| m.klass == index }
-      raise "No such middleware to insert #{where}: #{index.inspect}" unless i
-      i
-    end
-
-    def get_class(klass)
-      if klass.is_a?(String) || klass.is_a?(Symbol)
-        classcache = ActiveSupport::Dependencies::Reference
-        converted_klass = classcache[klass.to_s]
-        ActiveSupport::Deprecation.warn <<-eowarn
-Passing strings or symbols to the middleware builder is deprecated, please change
-them to actual class references.  For example:
-
-  "#{klass}" => #{converted_klass}
-
-        eowarn
-        converted_klass
-      else
-        klass
+      def assert_index(index, where)
+        i = index.is_a?(Integer) ? index : middlewares.index { |m| m.klass == index }
+        raise "No such middleware to insert #{where}: #{index.inspect}" unless i
+        i
       end
-    end
 
-    def build_middleware(klass, args, block)
-      Middleware.new(get_class(klass), args, block)
-    end
+      def build_middleware(klass, args, block)
+        Middleware.new(klass, args, block)
+      end
   end
 end
diff --git a/actionpack/lib/action_dispatch/middleware/static.rb b/actionpack/lib/action_dispatch/middleware/static.rb
index 2c5721dc22..23492e14eb 100644
--- a/actionpack/lib/action_dispatch/middleware/static.rb
+++ b/actionpack/lib/action_dispatch/middleware/static.rb
@@ -1,20 +1,22 @@
-require 'rack/utils'
-require 'active_support/core_ext/uri'
+# frozen_string_literal: true
+
+require "rack/utils"
+require "active_support/core_ext/uri"
 
 module ActionDispatch
   # This middleware returns a file's contents from disk in the body response.
   # When initialized, it can accept optional HTTP headers, which will be set
   # when a response containing a file's contents is delivered.
   #
-  # This middleware will render the file specified in `env["PATH_INFO"]`
+  # This middleware will render the file specified in <tt>env["PATH_INFO"]</tt>
   # where the base path is in the +root+ directory. For example, if the +root+
-  # is set to `public/`, then a request with `env["PATH_INFO"]` of
-  # `assets/application.js` will return a response with the contents of a file
-  # located at `public/assets/application.js` if the file exists. If the file
+  # is set to +public/+, then a request with <tt>env["PATH_INFO"]</tt> of
+  # +assets/application.js+ will return a response with the contents of a file
+  # located at +public/assets/application.js+ if the file exists. If the file
   # does not exist, a 404 "File not Found" response will be returned.
   class FileHandler
-    def initialize(root, index: 'index', headers: {})
-      @root          = root.chomp('/')
+    def initialize(root, index: "index", headers: {})
+      @root          = root.chomp("/")
       @file_server   = ::Rack::File.new(@root, headers)
       @index         = index
     end
@@ -23,8 +25,8 @@ module ActionDispatch
     # correct read permissions, the return value is a URI-escaped string
     # representing the filename. Otherwise, false is returned.
     #
-    # Used by the `Static` class to check the existence of a valid file
-    # in the server's `public/` directory (see Static#call).
+    # Used by the +Static+ class to check the existence of a valid file
+    # in the server's +public/+ directory (see Static#call).
     def match?(path)
       path = ::Rack::Utils.unescape_path path
       return false unless ::Rack::Utils.valid_path? path
@@ -33,7 +35,7 @@ module ActionDispatch
       paths = [path, "#{path}#{ext}", "#{path}/#{@index}#{ext}"]
 
       if match = paths.detect { |p|
-        path = File.join(@root, p.force_encoding('UTF-8'.freeze))
+        path = File.join(@root, p.dup.force_encoding(Encoding::UTF_8))
         begin
           File.file?(path) && File.readable?(path)
         rescue SystemCallError
@@ -46,7 +48,7 @@ module ActionDispatch
     end
 
     def call(env)
-      serve ActionDispatch::Request.new env
+      serve(Rack::Request.new(env))
     end
 
     def serve(request)
@@ -59,13 +61,13 @@ module ActionDispatch
         if status == 304
           return [status, headers, body]
         end
-        headers['Content-Encoding'] = 'gzip'
-        headers['Content-Type']     = content_type(path)
+        headers["Content-Encoding"] = "gzip"
+        headers["Content-Type"]     = content_type(path)
       else
         status, headers, body = @file_server.call(request.env)
       end
 
-      headers['Vary'] = 'Accept-Encoding' if gzip_path
+      headers["Vary"] = "Accept-Encoding" if gzip_path
 
       return [status, headers, body]
     ensure
@@ -78,11 +80,11 @@ module ActionDispatch
       end
 
       def content_type(path)
-        ::Rack::Mime.mime_type(::File.extname(path), 'text/plain'.freeze)
+        ::Rack::Mime.mime_type(::File.extname(path), "text/plain".freeze)
       end
 
       def gzip_encoding_accepted?(request)
-        request.accept_encoding =~ /\bgzip\b/i
+        request.accept_encoding.any? { |enc, quality| enc =~ /\bgzip\b/i }
       end
 
       def gzip_file_path(path)
@@ -99,30 +101,23 @@ module ActionDispatch
   # This middleware will attempt to return the contents of a file's body from
   # disk in the response. If a file is not found on disk, the request will be
   # delegated to the application stack. This middleware is commonly initialized
-  # to serve assets from a server's `public/` directory.
+  # to serve assets from a server's +public/+ directory.
   #
   # This middleware verifies the path to ensure that only files
   # living in the root directory can be rendered. A request cannot
   # produce a directory traversal using this middleware. Only 'GET' and 'HEAD'
   # requests will result in a file being returned.
   class Static
-    def initialize(app, path, deprecated_cache_control = :not_set, index: 'index', headers: {})
-      if deprecated_cache_control != :not_set
-        ActiveSupport::Deprecation.warn("The `cache_control` argument is deprecated," \
-                                        "replaced by `headers: { 'Cache-Control' => #{deprecated_cache_control} }`, " \
-                                        " and will be removed in Rails 5.1.")
-        headers['Cache-Control'.freeze] = deprecated_cache_control
-      end
-
+    def initialize(app, path, index: "index", headers: {})
       @app = app
       @file_handler = FileHandler.new(path, index: index, headers: headers)
     end
 
     def call(env)
-      req = ActionDispatch::Request.new env
+      req = Rack::Request.new env
 
       if req.get? || req.head?
-        path = req.path_info.chomp('/'.freeze)
+        path = req.path_info.chomp("/".freeze)
         if match = @file_handler.match?(path)
           req.path_info = match
           return @file_handler.serve(req)
diff --git a/actionpack/lib/action_dispatch/middleware/templates/rescues/layout.erb b/actionpack/lib/action_dispatch/middleware/templates/rescues/layout.erb
index e0509f56f4..39ea25bdfc 100644
--- a/actionpack/lib/action_dispatch/middleware/templates/rescues/layout.erb
+++ b/actionpack/lib/action_dispatch/middleware/templates/rescues/layout.erb
@@ -106,6 +106,7 @@
 
     .line {
       padding-left: 10px;
+      white-space: pre;
     }
 
     .line:hover {
diff --git a/actionpack/lib/action_dispatch/middleware/templates/routes/_table.html.erb b/actionpack/lib/action_dispatch/middleware/templates/routes/_table.html.erb
index 429ea7057c..1fa0691303 100644
--- a/actionpack/lib/action_dispatch/middleware/templates/routes/_table.html.erb
+++ b/actionpack/lib/action_dispatch/middleware/templates/routes/_table.html.erb
@@ -17,6 +17,10 @@
     line-height: 15px;
   }
 
+  #route_table thead tr.bottom th input#search {
+    -webkit-appearance: textfield;
+  }
+
   #route_table tbody tr {
     border-bottom: 1px solid #ddd;
   }
@@ -60,7 +64,7 @@
         <%= link_to "Path", "#", 'data-route-helper' => '_path',
                     title: "Returns a relative path (without the http or domain)" %> /
         <%= link_to "Url", "#", 'data-route-helper' => '_url',
-                    title: "Returns an absolute url (with the http and domain)"   %>
+                    title: "Returns an absolute URL (with the http and domain)"   %>
       </th>
       <th><%# HTTP Verb %>
       </th>
@@ -93,7 +97,7 @@
       }
     }
 
-    // get JSON from url and invoke callback with result
+    // get JSON from URL and invoke callback with result
     function getJSON(url, success) {
       var xhr = new XMLHttpRequest();
       xhr.open('GET', url);
diff --git a/actionpack/lib/action_dispatch/railtie.rb b/actionpack/lib/action_dispatch/railtie.rb
index e9e6a2e597..95e99987a0 100644
--- a/actionpack/lib/action_dispatch/railtie.rb
+++ b/actionpack/lib/action_dispatch/railtie.rb
@@ -1,4 +1,7 @@
+# frozen_string_literal: true
+
 require "action_dispatch"
+require "active_support/messages/rotation_configuration"
 
 module ActionDispatch
   class Railtie < Rails::Railtie # :nodoc:
@@ -8,22 +11,28 @@ module ActionDispatch
     config.action_dispatch.show_exceptions = true
     config.action_dispatch.tld_length = 1
     config.action_dispatch.ignore_accept_header = false
-    config.action_dispatch.rescue_templates = { }
-    config.action_dispatch.rescue_responses = { }
+    config.action_dispatch.rescue_templates = {}
+    config.action_dispatch.rescue_responses = {}
     config.action_dispatch.default_charset = nil
     config.action_dispatch.rack_cache = false
-    config.action_dispatch.http_auth_salt = 'http authentication'
-    config.action_dispatch.signed_cookie_salt = 'signed cookie'
-    config.action_dispatch.encrypted_cookie_salt = 'encrypted cookie'
-    config.action_dispatch.encrypted_signed_cookie_salt = 'signed encrypted cookie'
+    config.action_dispatch.http_auth_salt = "http authentication"
+    config.action_dispatch.signed_cookie_salt = "signed cookie"
+    config.action_dispatch.encrypted_cookie_salt = "encrypted cookie"
+    config.action_dispatch.encrypted_signed_cookie_salt = "signed encrypted cookie"
+    config.action_dispatch.authenticated_encrypted_cookie_salt = "authenticated encrypted cookie"
+    config.action_dispatch.use_authenticated_cookie_encryption = false
     config.action_dispatch.perform_deep_munge = true
 
     config.action_dispatch.default_headers = {
-      'X-Frame-Options' => 'SAMEORIGIN',
-      'X-XSS-Protection' => '1; mode=block',
-      'X-Content-Type-Options' => 'nosniff'
+      "X-Frame-Options" => "SAMEORIGIN",
+      "X-XSS-Protection" => "1; mode=block",
+      "X-Content-Type-Options" => "nosniff",
+      "X-Download-Options" => "noopen",
+      "X-Permitted-Cross-Domain-Policies" => "none"
     }
 
+    config.action_dispatch.cookies_rotations = ActiveSupport::Messages::RotationConfiguration.new
+
     config.eager_load_namespaces << ActionDispatch
 
     initializer "action_dispatch.configure" do |app|
@@ -39,8 +48,6 @@ module ActionDispatch
       config.action_dispatch.always_write_cookie = Rails.env.development? if config.action_dispatch.always_write_cookie.nil?
       ActionDispatch::Cookies::CookieJar.always_write_cookie = config.action_dispatch.always_write_cookie
 
-      ActionDispatch::Reloader.default_reloader = app.reloader
-
       ActionDispatch.test_app = app
     end
   end
diff --git a/actionpack/lib/action_dispatch/request/session.rb b/actionpack/lib/action_dispatch/request/session.rb
index 47568f6ad0..d86d0b10c2 100644
--- a/actionpack/lib/action_dispatch/request/session.rb
+++ b/actionpack/lib/action_dispatch/request/session.rb
@@ -1,4 +1,6 @@
-require 'rack/session/abstract/id'
+# frozen_string_literal: true
+
+require "rack/session/abstract/id"
 
 module ActionDispatch
   class Request
@@ -7,10 +9,10 @@ module ActionDispatch
       ENV_SESSION_KEY         = Rack::RACK_SESSION # :nodoc:
       ENV_SESSION_OPTIONS_KEY = Rack::RACK_SESSION_OPTIONS # :nodoc:
 
-      # Singleton object used to determine if an optional param wasn't specified
+      # Singleton object used to determine if an optional param wasn't specified.
       Unspecified = Object.new
 
-      # Creates a session hash, merging the properties of the previous session if any
+      # Creates a session hash, merging the properties of the previous session if any.
       def self.create(store, req, default_options)
         session_was = find req
         session     = Request::Session.new(store, req)
@@ -53,7 +55,7 @@ module ActionDispatch
           }
         end
 
-        def []=(k,v);         @delegate[k] = v; end
+        def []=(k, v);        @delegate[k] = v; end
         def to_hash;          @delegate.dup; end
         def values_at(*args); @delegate.values_at(*args); end
       end
@@ -63,7 +65,7 @@ module ActionDispatch
         @req      = req
         @delegate = {}
         @loaded   = false
-        @exists   = nil # we haven't checked yet
+        @exists   = nil # We haven't checked yet.
       end
 
       def id
@@ -79,13 +81,13 @@ module ActionDispatch
         options = self.options || {}
         @by.send(:delete_session, @req, options.id(@req), options)
 
-        # Load the new sid to be written with the response
+        # Load the new sid to be written with the response.
         @loaded = false
         load_for_write!
       end
 
       # Returns value of the key stored in the session or
-      # nil if the given key is not found in the session.
+      # +nil+ if the given key is not found in the session.
       def [](key)
         load_for_read!
         @delegate[key.to_s]
@@ -101,11 +103,13 @@ module ActionDispatch
 
       # Returns keys of the session as Array.
       def keys
+        load_for_read!
         @delegate.keys
       end
 
       # Returns values of the session as Array.
       def values
+        load_for_read!
         @delegate.values
       end
 
@@ -124,7 +128,7 @@ module ActionDispatch
       # Returns the session as Hash.
       def to_hash
         load_for_read!
-        @delegate.dup.delete_if { |_,v| v.nil? }
+        @delegate.dup.delete_if { |_, v| v.nil? }
       end
 
       # Updates the session with given Hash.
@@ -162,7 +166,7 @@ module ActionDispatch
       #     :bar
       #   end
       #   # => :bar
-      def fetch(key, default=Unspecified, &block)
+      def fetch(key, default = Unspecified, &block)
         load_for_read!
         if default == Unspecified
           @delegate.fetch(key.to_s, &block)
@@ -204,26 +208,26 @@ module ActionDispatch
 
       private
 
-      def load_for_read!
-        load! if !loaded? && exists?
-      end
+        def load_for_read!
+          load! if !loaded? && exists?
+        end
 
-      def load_for_write!
-        load! unless loaded?
-      end
+        def load_for_write!
+          load! unless loaded?
+        end
 
-      def load!
-        id, session = @by.load_session @req
-        options[:id] = id
-        @delegate.replace(stringify_keys(session))
-        @loaded = true
-      end
+        def load!
+          id, session = @by.load_session @req
+          options[:id] = id
+          @delegate.replace(stringify_keys(session))
+          @loaded = true
+        end
 
-      def stringify_keys(other)
-        other.each_with_object({}) { |(key, value), hash|
-          hash[key.to_s] = value
-        }
-      end
+        def stringify_keys(other)
+          other.each_with_object({}) { |(key, value), hash|
+            hash[key.to_s] = value
+          }
+        end
     end
   end
 end
diff --git a/actionpack/lib/action_dispatch/request/utils.rb b/actionpack/lib/action_dispatch/request/utils.rb
index bb3df3c311..0ae464082d 100644
--- a/actionpack/lib/action_dispatch/request/utils.rb
+++ b/actionpack/lib/action_dispatch/request/utils.rb
@@ -1,9 +1,20 @@
+# frozen_string_literal: true
+
 module ActionDispatch
   class Request
     class Utils # :nodoc:
+      mattr_accessor :perform_deep_munge, default: true
 
-      mattr_accessor :perform_deep_munge
-      self.perform_deep_munge = true
+      def self.each_param_value(params, &block)
+        case params
+        when Array
+          params.each { |element| each_param_value(element, &block) }
+        when Hash
+          params.each_value { |value| each_param_value(value, &block) }
+        when String
+          block.call params
+        end
+      end
 
       def self.normalize_encode_params(params)
         if perform_deep_munge
@@ -23,14 +34,13 @@ module ActionDispatch
           unless params.valid_encoding?
             # Raise Rack::Utils::InvalidParameterError for consistency with Rack.
             # ActionDispatch::Request#GET will re-raise as a BadRequest error.
-            raise Rack::Utils::InvalidParameterError, "Non UTF-8 value: #{params}"
+            raise Rack::Utils::InvalidParameterError, "Invalid encoding for parameter: #{params.scrub}"
           end
         end
       end
 
       class ParamEncoder # :nodoc:
         # Convert nested Hash to HashWithIndifferentAccess.
-        #
         def self.normalize_encode_params(params)
           case params
           when Array
@@ -53,7 +63,7 @@ module ActionDispatch
         end
       end
 
-      # Remove nils from the params hash
+      # Remove nils from the params hash.
       class NoNilParamEncoder < ParamEncoder # :nodoc:
         def self.handle_array(params)
           list = super
@@ -64,4 +74,3 @@ module ActionDispatch
     end
   end
 end
-
diff --git a/actionpack/lib/action_dispatch/routing.rb b/actionpack/lib/action_dispatch/routing.rb
index 61ebd0b8db..72f7407c6e 100644
--- a/actionpack/lib/action_dispatch/routing.rb
+++ b/actionpack/lib/action_dispatch/routing.rb
@@ -1,3 +1,7 @@
+# frozen_string_literal: true
+
+require "active_support/core_ext/string/filters"
+
 module ActionDispatch
   # The routing module provides URL rewriting in native Ruby. It's a way to
   # redirect incoming requests to controllers and actions. This replaces
@@ -118,7 +122,7 @@ module ActionDispatch
   #   controller :blog do
   #     get 'blog/show'     => :list
   #     get 'blog/delete'   => :delete
-  #     get 'blog/edit' => :edit
+  #     get 'blog/edit'     => :edit
   #   end
   #
   #   # provides named routes for show, delete, and edit
@@ -252,14 +256,5 @@ module ActionDispatch
 
     SEPARATORS = %w( / . ? ) #:nodoc:
     HTTP_METHODS = [:get, :head, :post, :patch, :put, :delete, :options] #:nodoc:
-
-    #:stopdoc:
-    INSECURE_URL_PARAMETERS_MESSAGE = <<-MSG.squish
-      Attempting to generate a URL from non-sanitized request parameters!
-
-      An attacker can inject malicious data into the generated URL, such as
-      changing the host. Whitelist and sanitize passed parameters to be secure.
-    MSG
-    #:startdoc:
   end
 end
diff --git a/actionpack/lib/action_dispatch/routing/endpoint.rb b/actionpack/lib/action_dispatch/routing/endpoint.rb
index 88aa13c3e8..24dced1efd 100644
--- a/actionpack/lib/action_dispatch/routing/endpoint.rb
+++ b/actionpack/lib/action_dispatch/routing/endpoint.rb
@@ -1,10 +1,14 @@
+# frozen_string_literal: true
+
 module ActionDispatch
   module Routing
     class Endpoint # :nodoc:
-      def dispatcher?;   false; end
-      def redirect?;     false; end
-      def matches?(req); true;  end
-      def app;           self;  end
+      def dispatcher?;                           false; end
+      def redirect?;                             false; end
+      def engine?;       rack_app.respond_to?(:routes); end
+      def matches?(req);                          true; end
+      def app;                                    self; end
+      def rack_app;                                app; end
     end
   end
 end
diff --git a/actionpack/lib/action_dispatch/routing/inspector.rb b/actionpack/lib/action_dispatch/routing/inspector.rb
index 2459a45827..a2205569b4 100644
--- a/actionpack/lib/action_dispatch/routing/inspector.rb
+++ b/actionpack/lib/action_dispatch/routing/inspector.rb
@@ -1,5 +1,7 @@
-require 'delegate'
-require 'active_support/core_ext/string/strip'
+# frozen_string_literal: true
+
+require "delegate"
+require "active_support/core_ext/string/strip"
 
 module ActionDispatch
   module Routing
@@ -13,7 +15,7 @@ module ActionDispatch
       end
 
       def rack_app
-        app.app
+        app.rack_app
       end
 
       def path
@@ -33,11 +35,11 @@ module ActionDispatch
       end
 
       def controller
-        parts.include?(:controller) ? ':controller' : requirements[:controller]
+        parts.include?(:controller) ? ":controller" : requirements[:controller]
       end
 
       def action
-        parts.include?(:action) ? ':action' : requirements[:action]
+        parts.include?(:action) ? ":action" : requirements[:action]
       end
 
       def internal?
@@ -45,7 +47,7 @@ module ActionDispatch
       end
 
       def engine?
-        rack_app.respond_to?(:routes)
+        app.engine?
       end
     end
 
@@ -80,48 +82,48 @@ module ActionDispatch
 
       private
 
-      def normalize_filter(filter)
-        if filter.is_a?(Hash) && filter[:controller]
-          { controller: /#{filter[:controller].downcase.sub(/_?controller\z/, '').sub('::', '/')}/ }
-        elsif filter
-          { controller: /#{filter}/, action: /#{filter}/, verb: /#{filter}/, name: /#{filter}/, path: /#{filter}/ }
+        def normalize_filter(filter)
+          if filter.is_a?(Hash) && filter[:controller]
+            { controller: /#{filter[:controller].downcase.sub(/_?controller\z/, '').sub('::', '/')}/ }
+          elsif filter
+            { controller: /#{filter}/, action: /#{filter}/, verb: /#{filter}/, name: /#{filter}/, path: /#{filter}/ }
+          end
         end
-      end
 
-      def filter_routes(filter)
-        if filter
-          @routes.select do |route|
-            route_wrapper = RouteWrapper.new(route)
-            filter.any? { |default, value| route_wrapper.send(default) =~ value }
+        def filter_routes(filter)
+          if filter
+            @routes.select do |route|
+              route_wrapper = RouteWrapper.new(route)
+              filter.any? { |default, value| route_wrapper.send(default) =~ value }
+            end
+          else
+            @routes
           end
-        else
-          @routes
         end
-      end
 
-      def collect_routes(routes)
-        routes.collect do |route|
-          RouteWrapper.new(route)
-        end.reject(&:internal?).collect do |route|
-          collect_engine_routes(route)
+        def collect_routes(routes)
+          routes.collect do |route|
+            RouteWrapper.new(route)
+          end.reject(&:internal?).collect do |route|
+            collect_engine_routes(route)
 
-          { name: route.name,
-            verb: route.verb,
-            path: route.path,
-            reqs: route.reqs }
+            { name: route.name,
+              verb: route.verb,
+              path: route.path,
+              reqs: route.reqs }
+          end
         end
-      end
 
-      def collect_engine_routes(route)
-        name = route.endpoint
-        return unless route.engine?
-        return if @engines[name]
+        def collect_engine_routes(route)
+          name = route.endpoint
+          return unless route.engine?
+          return if @engines[name]
 
-        routes = route.rack_app.routes
-        if routes.is_a?(ActionDispatch::Routing::RouteSet)
-          @engines[name] = collect_routes(routes.routes)
+          routes = route.rack_app.routes
+          if routes.is_a?(ActionDispatch::Routing::RouteSet)
+            @engines[name] = collect_routes(routes.routes)
+          end
         end
-      end
     end
 
     class ConsoleFormatter
@@ -161,7 +163,7 @@ module ActionDispatch
 
       private
         def draw_section(routes)
-          header_lengths = ['Prefix', 'Verb', 'URI Pattern'].map(&:length)
+          header_lengths = ["Prefix", "Verb", "URI Pattern"].map(&:length)
           name_width, verb_width, path_width = widths(routes).zip(header_lengths).map(&:max)
 
           routes.map do |r|
@@ -196,7 +198,7 @@ module ActionDispatch
         @buffer << @view.render(partial: "routes/route", collection: routes)
       end
 
-      # the header is part of the HTML page, so we don't construct it here.
+      # The header is part of the HTML page, so we don't construct it here.
       def header(routes)
       end
 
diff --git a/actionpack/lib/action_dispatch/routing/mapper.rb b/actionpack/lib/action_dispatch/routing/mapper.rb
index 40b6500553..d87a23a58c 100644
--- a/actionpack/lib/action_dispatch/routing/mapper.rb
+++ b/actionpack/lib/action_dispatch/routing/mapper.rb
@@ -1,9 +1,11 @@
-require 'active_support/core_ext/hash/slice'
-require 'active_support/core_ext/enumerable'
-require 'active_support/core_ext/array/extract_options'
-require 'active_support/core_ext/regexp'
-require 'action_dispatch/routing/redirection'
-require 'action_dispatch/routing/endpoint'
+# frozen_string_literal: true
+
+require "active_support/core_ext/hash/slice"
+require "active_support/core_ext/enumerable"
+require "active_support/core_ext/array/extract_options"
+require "active_support/core_ext/regexp"
+require "action_dispatch/routing/redirection"
+require "action_dispatch/routing/endpoint"
 
 module ActionDispatch
   module Routing
@@ -17,9 +19,9 @@ module ActionDispatch
         CALL  = ->(app, req) { app.call req.env }
 
         def initialize(app, constraints, strategy)
-          # Unwrap Constraints objects.  I don't actually think it's possible
+          # Unwrap Constraints objects. I don't actually think it's possible
           # to pass a Constraints object to this constructor, but there were
-          # multiple places that kept testing children of this object.  I
+          # multiple places that kept testing children of this object. I
           # *think* they were just being defensive, but I have no idea.
           if app.is_a?(self.class)
             constraints += app.constraints
@@ -41,7 +43,7 @@ module ActionDispatch
         end
 
         def serve(req)
-          return [ 404, {'X-Cascade' => 'pass'}, [] ] unless matches?(req)
+          return [ 404, { "X-Cascade" => "pass" }, [] ] unless matches?(req)
 
           @strategy.call @app, req
         end
@@ -54,6 +56,7 @@ module ActionDispatch
 
       class Mapping #:nodoc:
         ANCHOR_CHARACTERS_REGEX = %r{\A(\\A|\^)|(\\Z|\\z|\$)\Z}
+        OPTIONAL_FORMAT_REGEX = %r{(?:\(\.:format\)+|\.:format|/)\Z}
 
         attr_reader :requirements, :defaults
         attr_reader :to, :default_controller, :default_action
@@ -93,7 +96,7 @@ module ActionDispatch
         end
 
         def self.optional_format?(path, format)
-          format != false && !path.include?(':format') && !path.end_with?('/')
+          format != false && path !~ OPTIONAL_FORMAT_REGEX
         end
 
         def initialize(set, ast, defaults, controller, default_action, modyoule, to, formatted, scope_constraints, blocks, via, options_constraints, anchor, options)
@@ -138,7 +141,7 @@ module ActionDispatch
           @defaults = formats[:defaults].merge(@defaults).merge(normalize_defaults(options))
 
           if path_params.include?(:action) && !@requirements.key?(:action)
-            @defaults[:action] ||= 'index'
+            @defaults[:action] ||= "index"
           end
 
           @required_defaults = (split_options[:required_defaults] || []).map(&:first)
@@ -218,7 +221,7 @@ module ActionDispatch
         private
           def add_wildcard_options(options, formatted, path_ast)
             # Add a constraint for wildcard route to make it non-greedy and match the
-            # optional format part of the route by default
+            # optional format part of the route by default.
             if formatted != false
               path_ast.grep(Journey::Nodes::Star).each_with_object({}) { |node, hash|
                 hash[node.name.to_sym] ||= /.+?/
@@ -239,7 +242,7 @@ module ActionDispatch
               options[:controller] ||= /.+?/
             end
 
-            if to.respond_to? :call
+            if to.respond_to?(:action) || to.respond_to?(:call)
               options
             else
               to_endpoint = split_to to
@@ -270,7 +273,7 @@ module ActionDispatch
               { requirements: { format: Regexp.compile(formatted) },
                 defaults:     { format: formatted } }
             else
-              { requirements: { }, defaults: { } }
+              { requirements: {}, defaults: {} }
             end
           end
 
@@ -291,23 +294,21 @@ module ActionDispatch
           end
 
           def app(blocks)
-            if to.is_a?(Class) && to < ActionController::Metal
+            if to.respond_to?(:action)
               Routing::RouteSet::StaticDispatcher.new to
+            elsif to.respond_to?(:call)
+              Constraints.new(to, blocks, Constraints::CALL)
+            elsif blocks.any?
+              Constraints.new(dispatcher(defaults.key?(:controller)), blocks, Constraints::SERVE)
             else
-              if to.respond_to?(:call)
-                Constraints.new(to, blocks, Constraints::CALL)
-              elsif blocks.any?
-                Constraints.new(dispatcher(defaults.key?(:controller)), blocks, Constraints::SERVE)
-              else
-                dispatcher(defaults.key?(:controller))
-              end
+              dispatcher(defaults.key?(:controller))
             end
           end
 
           def check_controller_and_action(path_params, controller, action)
             hash = check_part(:controller, controller, path_params, {}) do |part|
               translate_controller(part) {
-                message = "'#{part}' is not a supported controller name. This can lead to potential routing problems."
+                message = "'#{part}' is not a supported controller name. This can lead to potential routing problems.".dup
                 message << " See http://guides.rubyonrails.org/routing.html#specifying-a-controller-to-use"
 
                 raise ArgumentError, message
@@ -333,7 +334,7 @@ module ActionDispatch
 
           def split_to(to)
             if to =~ /#/
-              to.split('#')
+              to.split("#")
             else
               []
             end
@@ -398,7 +399,7 @@ module ActionDispatch
       end
 
       module Base
-        # Matches a url pattern to one or more routes.
+        # Matches a URL pattern to one or more routes.
         #
         # You should not use the +match+ method in your router
         # without specifying an HTTP method.
@@ -408,7 +409,7 @@ module ActionDispatch
         #   # sets :controller, :action and :id in params
         #   match ':controller/:action/:id', via: [:get, :post]
         #
-        # Note that +:controller+, +:action+ and +:id+ are interpreted as url
+        # Note that +:controller+, +:action+ and +:id+ are interpreted as URL
         # query parameters and thus available through +params+ in an action.
         #
         # If you want to expose your action to GET, use +get+ in the router:
@@ -457,7 +458,7 @@ module ActionDispatch
         #
         # === Options
         #
-        # Any options not seen here are passed on as params with the url.
+        # Any options not seen here are passed on as params with the URL.
         #
         # [:controller]
         #   The route's controller.
@@ -472,7 +473,17 @@ module ActionDispatch
         #   <tt>params[<:param>]</tt>.
         #   In your router:
         #
-        #      resources :user, param: :name
+        #      resources :users, param: :name
+        #
+        #   The +users+ resource here will have the following routes generated for it:
+        #
+        #      GET       /users(.:format)
+        #      POST      /users(.:format)
+        #      GET       /users/new(.:format)
+        #      GET       /users/:name/edit(.:format)
+        #      GET       /users/:name(.:format)
+        #      PATCH/PUT /users/:name(.:format)
+        #      DELETE    /users/:name(.:format)
         #
         #   You can override <tt>ActiveRecord::Base#to_param</tt> of a related
         #   model to construct a URL:
@@ -483,8 +494,8 @@ module ActionDispatch
         #        end
         #      end
         #
-        #   user = User.find_by(name: 'Phusion')
-        #   user_path(user)  # => "/users/Phusion"
+        #      user = User.find_by(name: 'Phusion')
+        #      user_path(user)  # => "/users/Phusion"
         #
         # [:path]
         #   The path prefix for the routes.
@@ -568,7 +579,7 @@ module ActionDispatch
         # [:format]
         #   Allows you to specify the default value for optional +format+
         #   segment or disable it by supplying +false+.
-        def match(path, options=nil)
+        def match(path, options = nil)
         end
 
         # Mount a Rack-based application to be used within the application.
@@ -614,7 +625,7 @@ module ActionDispatch
           target_as       = name_for_action(options[:as], path)
           options[:via] ||= :all
 
-          match(path, options.merge(:to => app, :anchor => false, :format => false))
+          match(path, options.merge(to: app, anchor: false, format: false))
 
           define_generate_prefix(app, target_as) if rails_app
           self
@@ -653,18 +664,30 @@ module ActionDispatch
           def define_generate_prefix(app, name)
             _route = @set.named_routes.get name
             _routes = @set
-            app.routes.define_mounted_helper(name)
+
+            script_namer = ->(options) do
+              prefix_options = options.slice(*_route.segment_keys)
+              prefix_options[:relative_url_root] = "".freeze
+
+              if options[:_recall]
+                prefix_options.reverse_merge!(options[:_recall].slice(*_route.segment_keys))
+              end
+
+              # We must actually delete prefix segment keys to avoid passing them to next url_for.
+              _route.segment_keys.each { |k| options.delete(k) }
+              _routes.url_helpers.send("#{name}_path", prefix_options)
+            end
+
+            app.routes.define_mounted_helper(name, script_namer)
+
             app.routes.extend Module.new {
               def optimize_routes_generation?; false; end
+
               define_method :find_script_name do |options|
                 if options.key? :script_name
                   super(options)
                 else
-                  prefix_options = options.slice(*_route.segment_keys)
-                  prefix_options[:relative_url_root] = ''.freeze
-                  # we must actually delete prefix segment keys to avoid passing them to next url_for
-                  _route.segment_keys.each { |k| options.delete(k) }
-                  _routes.url_helpers.send("#{name}_path", prefix_options)
+                  script_namer.call(options)
                 end
               end
             }
@@ -716,11 +739,7 @@ module ActionDispatch
           def map_method(method, args, &block)
             options = args.extract_options!
             options[:via] = method
-            if options.key?(:defaults)
-              defaults(options.delete(:defaults)) { match(*args, options, &block) }
-            else
-              match(*args, options, &block)
-            end
+            match(*args, options, &block)
             self
           end
       end
@@ -814,7 +833,7 @@ module ActionDispatch
           options = args.extract_options!.dup
           scope = {}
 
-          options[:path] = args.flatten.join('/') if args.any?
+          options[:path] = args.flatten.join("/") if args.any?
           options[:constraints] ||= {}
 
           unless nested_scope?
@@ -838,7 +857,7 @@ module ActionDispatch
           end
 
           if options.key? :anchor
-            raise ArgumentError, 'anchor is ignored unless passed to `match`'
+            raise ArgumentError, "anchor is ignored unless passed to `match`"
           end
 
           @scope.options.each do |option|
@@ -985,7 +1004,7 @@ module ActionDispatch
         #      resources :iphones
         #    end
         def constraints(constraints = {})
-          scope(:constraints => constraints) { yield }
+          scope(constraints: constraints) { yield }
         end
 
         # Allows you to set default parameters for a route, such as this:
@@ -1001,67 +1020,71 @@ module ActionDispatch
         end
 
         private
-          def merge_path_scope(parent, child) #:nodoc:
+          def merge_path_scope(parent, child)
             Mapper.normalize_path("#{parent}/#{child}")
           end
 
-          def merge_shallow_path_scope(parent, child) #:nodoc:
+          def merge_shallow_path_scope(parent, child)
             Mapper.normalize_path("#{parent}/#{child}")
           end
 
-          def merge_as_scope(parent, child) #:nodoc:
+          def merge_as_scope(parent, child)
             parent ? "#{parent}_#{child}" : child
           end
 
-          def merge_shallow_prefix_scope(parent, child) #:nodoc:
+          def merge_shallow_prefix_scope(parent, child)
             parent ? "#{parent}_#{child}" : child
           end
 
-          def merge_module_scope(parent, child) #:nodoc:
+          def merge_module_scope(parent, child)
             parent ? "#{parent}/#{child}" : child
           end
 
-          def merge_controller_scope(parent, child) #:nodoc:
+          def merge_controller_scope(parent, child)
             child
           end
 
-          def merge_action_scope(parent, child) #:nodoc:
+          def merge_action_scope(parent, child)
             child
           end
 
-          def merge_via_scope(parent, child) #:nodoc:
+          def merge_via_scope(parent, child)
             child
           end
 
-          def merge_format_scope(parent, child) #:nodoc:
+          def merge_format_scope(parent, child)
             child
           end
 
-          def merge_path_names_scope(parent, child) #:nodoc:
+          def merge_path_names_scope(parent, child)
             merge_options_scope(parent, child)
           end
 
-          def merge_constraints_scope(parent, child) #:nodoc:
+          def merge_constraints_scope(parent, child)
             merge_options_scope(parent, child)
           end
 
-          def merge_defaults_scope(parent, child) #:nodoc:
+          def merge_defaults_scope(parent, child)
             merge_options_scope(parent, child)
           end
 
-          def merge_blocks_scope(parent, child) #:nodoc:
+          def merge_blocks_scope(parent, child)
             merged = parent ? parent.dup : []
             merged << child if child
             merged
           end
 
-          def merge_options_scope(parent, child) #:nodoc:
+          def merge_options_scope(parent, child)
             (parent || {}).merge(child)
           end
 
-          def merge_shallow_scope(parent, child) #:nodoc:
+          def merge_shallow_scope(parent, child)
             child ? true : false
           end
+
+          def merge_to_scope(parent, child)
+            child
+          end
       end
 
       # Resource routing allows you to quickly declare all of the common routes
@@ -1240,19 +1263,19 @@ module ActionDispatch
         #
         #   resource :profile
         #
-        # creates six different routes in your application, all mapping to
+        # This creates six different routes in your application, all mapping to
         # the +Profiles+ controller (note that the controller is named after
         # the plural):
         #
         #   GET       /profile/new
-        #   POST      /profile
         #   GET       /profile
         #   GET       /profile/edit
         #   PATCH/PUT /profile
         #   DELETE    /profile
+        #   POST      /profile
         #
         # === Options
-        # Takes same options as +resources+.
+        # Takes same options as resources[rdoc-ref:#resources]
         def resource(*resources, &block)
           options = resources.extract_options!.dup
 
@@ -1267,15 +1290,15 @@ module ActionDispatch
 
               concerns(options[:concerns]) if options[:concerns]
 
-              collection do
-                post :create
-              end if parent_resource.actions.include?(:create)
-
               new do
                 get :new
               end if parent_resource.actions.include?(:new)
 
               set_member_mappings_for_resource
+
+              collection do
+                post :create
+              end if parent_resource.actions.include?(:create)
             end
           end
 
@@ -1317,7 +1340,7 @@ module ActionDispatch
         #   DELETE    /photos/:photo_id/comments/:id
         #
         # === Options
-        # Takes same options as <tt>Base#match</tt> as well as:
+        # Takes same options as match[rdoc-ref:Base#match] as well as:
         #
         # [:path_names]
         #   Allows you to change the segment component of the +edit+ and +new+ actions.
@@ -1325,14 +1348,14 @@ module ActionDispatch
         #
         #     resources :posts, path_names: { new: "brand_new" }
         #
-        #   The above example will now change /posts/new to /posts/brand_new
+        #   The above example will now change /posts/new to /posts/brand_new.
         #
         # [:path]
         #   Allows you to change the path prefix for the resource.
         #
         #     resources :posts, path: 'postings'
         #
-        #   The resource and all segments will now route to /postings instead of /posts
+        #   The resource and all segments will now route to /postings instead of /posts.
         #
         # [:only]
         #   Only generate routes for the given actions.
@@ -1527,7 +1550,7 @@ module ActionDispatch
           end
         end
 
-        # See ActionDispatch::Routing::Mapper::Scoping#namespace
+        # See ActionDispatch::Routing::Mapper::Scoping#namespace.
         def namespace(path, options = {})
           if resource_scope?
             nested { super }
@@ -1547,17 +1570,19 @@ module ActionDispatch
           !parent_resource.singleton? && @scope[:shallow]
         end
 
-        # Matches a url pattern to one or more routes.
+        # Matches a URL pattern to one or more routes.
         # For more information, see match[rdoc-ref:Base#match].
         #
         #   match 'path' => 'controller#action', via: patch
         #   match 'path', to: 'controller#action', via: :post
         #   match 'path', 'otherpath', on: :member, via: :get
-        def match(path, *rest)
+        def match(path, *rest, &block)
           if rest.empty? && Hash === path
             options  = path
             path, to = options.find { |name, _value| name.is_a?(String) }
 
+            raise ArgumentError, "Route path not specified" if path.nil?
+
             case to
             when Symbol
               options[:action] = to
@@ -1578,110 +1603,13 @@ module ActionDispatch
             paths = [path] + rest
           end
 
-          if options[:on] && !VALID_ON_OPTIONS.include?(options[:on])
-            raise ArgumentError, "Unknown scope #{on.inspect} given to :on"
-          end
-
-          if @scope[:controller] && @scope[:action]
-            options[:to] ||= "#{@scope[:controller]}##{@scope[:action]}"
-          end
-
-          controller = options.delete(:controller) || @scope[:controller]
-          option_path = options.delete :path
-          to = options.delete :to
-          via = Mapping.check_via Array(options.delete(:via) {
-            @scope[:via]
-          })
-          formatted = options.delete(:format) { @scope[:format] }
-          anchor = options.delete(:anchor) { true }
-          options_constraints = options.delete(:constraints) || {}
-
-          path_types = paths.group_by(&:class)
-          path_types.fetch(String, []).each do |_path|
-            route_options = options.dup
-            if _path && option_path
-              ActiveSupport::Deprecation.warn <<-eowarn
-Specifying strings for both :path and the route path is deprecated. Change things like this:
-
-  match #{_path.inspect}, :path => #{option_path.inspect}
-
-to this:
-
-  match #{option_path.inspect}, :as => #{_path.inspect}, :action => #{path.inspect}
-              eowarn
-              route_options[:action] = _path
-              route_options[:as] = _path
-              _path = option_path
-            end
-            to = get_to_from_path(_path, to, route_options[:action])
-            decomposed_match(_path, controller, route_options, _path, to, via, formatted, anchor, options_constraints)
-          end
-
-          path_types.fetch(Symbol, []).each do |action|
-            route_options = options.dup
-            decomposed_match(action, controller, route_options, option_path, to, via, formatted, anchor, options_constraints)
-          end
-
-          self
-        end
-
-        def get_to_from_path(path, to, action)
-          return to if to || action
-
-          path_without_format = path.sub(/\(\.:format\)$/, '')
-          if using_match_shorthand?(path_without_format)
-            path_without_format.gsub(%r{^/}, "").sub(%r{/([^/]*)$}, '#\1').tr("-", "_")
+          if options.key?(:defaults)
+            defaults(options.delete(:defaults)) { map_match(paths, options, &block) }
           else
-            nil
+            map_match(paths, options, &block)
           end
         end
 
-        def using_match_shorthand?(path)
-          path =~ %r{^/?[-\w]+/[-\w/]+$}
-        end
-
-        def decomposed_match(path, controller, options, _path, to, via, formatted, anchor, options_constraints) # :nodoc:
-          if on = options.delete(:on)
-            send(on) { decomposed_match(path, controller, options, _path, to, via, formatted, anchor, options_constraints) }
-          else
-            case @scope.scope_level
-            when :resources
-              nested { decomposed_match(path, controller, options, _path, to, via, formatted, anchor, options_constraints) }
-            when :resource
-              member { decomposed_match(path, controller, options, _path, to, via, formatted, anchor, options_constraints) }
-            else
-              add_route(path, controller, options, _path, to, via, formatted, anchor, options_constraints)
-            end
-          end
-        end
-
-        def add_route(action, controller, options, _path, to, via, formatted, anchor, options_constraints) # :nodoc:
-          path = path_for_action(action, _path)
-          raise ArgumentError, "path is required" if path.blank?
-
-          action = action.to_s
-
-          default_action = options.delete(:action) || @scope[:action]
-
-          if action =~ /^[\w\-\/]+$/
-            default_action ||= action.tr('-', '_') unless action.include?("/")
-          else
-            action = nil
-          end
-
-          as = if !options.fetch(:as, true) # if it's set to nil or false
-                 options.delete(:as)
-               else
-                 name_for_action(options.delete(:as), action)
-               end
-
-          path = Mapping.normalize_path URI.parser.escape(path), formatted
-          ast = Journey::Parser.parse path
-
-          mapping = Mapping.build(@scope, @set, ast, controller, default_action, to, via, formatted, options_constraints, anchor, options)
-          @set.add_route(mapping, ast, as, anchor)
-        end
-
         # You can specify what Rails should route "/" to with the root method:
         #
         #   root to: 'pages#main'
@@ -1698,7 +1626,7 @@ to this:
         def root(path, options = {})
           if path.is_a?(String)
             options[:to] = path
-          elsif path.is_a?(Hash) and options.empty?
+          elsif path.is_a?(Hash) && options.empty?
             options = path
           else
             raise ArgumentError, "must be called with a path and/or options"
@@ -1715,13 +1643,13 @@ to this:
           end
         end
 
-        protected
+        private
 
-          def parent_resource #:nodoc:
+          def parent_resource
             @scope[:scope_level_resource]
           end
 
-          def apply_common_behavior_for(method, resources, options, &block) #:nodoc:
+          def apply_common_behavior_for(method, resources, options, &block)
             if resources.length > 1
               resources.each { |r| send(method, r, options, &block) }
               return true
@@ -1754,48 +1682,48 @@ to this:
             false
           end
 
-          def apply_action_options(options) # :nodoc:
+          def apply_action_options(options)
             return options if action_options? options
             options.merge scope_action_options
           end
 
-          def action_options?(options) #:nodoc:
+          def action_options?(options)
             options[:only] || options[:except]
           end
 
-          def scope_action_options #:nodoc:
+          def scope_action_options
             @scope[:action_options] || {}
           end
 
-          def resource_scope? #:nodoc:
+          def resource_scope?
             @scope.resource_scope?
           end
 
-          def resource_method_scope? #:nodoc:
+          def resource_method_scope?
             @scope.resource_method_scope?
           end
 
-          def nested_scope? #:nodoc:
+          def nested_scope?
             @scope.nested?
           end
 
-          def with_scope_level(kind)
+          def with_scope_level(kind) # :doc:
             @scope = @scope.new_level(kind)
             yield
           ensure
             @scope = @scope.parent
           end
 
-          def resource_scope(resource) #:nodoc:
-            @scope = @scope.new(:scope_level_resource => resource)
+          def resource_scope(resource)
+            @scope = @scope.new(scope_level_resource: resource)
 
             controller(resource.resource_scope) { yield }
           ensure
             @scope = @scope.parent
           end
 
-          def nested_options #:nodoc:
-            options = { :as => parent_resource.member_name }
+          def nested_options
+            options = { as: parent_resource.member_name }
             options[:constraints] = {
               parent_resource.nested_param => param_constraint
             } if param_constraint?
@@ -1803,27 +1731,27 @@ to this:
             options
           end
 
-          def shallow_nesting_depth #:nodoc:
+          def shallow_nesting_depth
             @scope.find_all { |node|
               node.frame[:scope_level_resource]
             }.count { |node| node.frame[:scope_level_resource].shallow? }
           end
 
-          def param_constraint? #:nodoc:
+          def param_constraint?
             @scope[:constraints] && @scope[:constraints][parent_resource.param].is_a?(Regexp)
           end
 
-          def param_constraint #:nodoc:
+          def param_constraint
             @scope[:constraints][parent_resource.param]
           end
 
-          def canonical_action?(action) #:nodoc:
+          def canonical_action?(action)
             resource_method_scope? && CANONICAL_ACTIONS.include?(action.to_s)
           end
 
-          def shallow_scope #:nodoc:
-            scope = { :as   => @scope[:shallow_prefix],
-                      :path => @scope[:shallow_path] }
+          def shallow_scope
+            scope = { as: @scope[:shallow_prefix],
+                      path: @scope[:shallow_path] }
             @scope = @scope.new scope
 
             yield
@@ -1831,7 +1759,7 @@ to this:
             @scope = @scope.parent
           end
 
-          def path_for_action(action, path) #:nodoc:
+          def path_for_action(action, path)
             return "#{@scope[:path]}/#{path}" if path
 
             if canonical_action?(action)
@@ -1841,23 +1769,23 @@ to this:
             end
           end
 
-          def action_path(name) #:nodoc:
+          def action_path(name)
             @scope[:path_names][name.to_sym] || name
           end
 
-          def prefix_name_for_action(as, action) #:nodoc:
+          def prefix_name_for_action(as, action)
             if as
               prefix = as
             elsif !canonical_action?(action)
               prefix = action
             end
 
-            if prefix && prefix != '/' && !prefix.empty?
-              Mapper.normalize_name prefix.to_s.tr('-', '_')
+            if prefix && prefix != "/" && !prefix.empty?
+              Mapper.normalize_name prefix.to_s.tr("-", "_")
             end
           end
 
-          def name_for_action(as, action) #:nodoc:
+          def name_for_action(as, action)
             prefix = prefix_name_for_action(as, action)
             name_prefix = @scope[:as]
 
@@ -1869,7 +1797,7 @@ to this:
             end
 
             action_name = @scope.action_name(name_prefix, prefix, collection_name, member_name)
-            candidate = action_name.select(&:present?).join('_')
+            candidate = action_name.select(&:present?).join("_")
 
             unless candidate.empty?
               # If a name was not explicitly given, we check if it is valid
@@ -1883,7 +1811,7 @@ to this:
             end
           end
 
-          def set_member_mappings_for_resource
+          def set_member_mappings_for_resource # :doc:
             member do
               get :edit if parent_resource.actions.include?(:edit)
               get :show if parent_resource.actions.include?(:show)
@@ -1895,22 +1823,121 @@ to this:
             end
           end
 
-          def api_only?
+          def api_only? # :doc:
             @set.api_only?
           end
-        private
 
-        def path_scope(path)
-          @scope = @scope.new(path: merge_path_scope(@scope[:path], path))
-          yield
-        ensure
-          @scope = @scope.parent
-        end
+          def path_scope(path)
+            @scope = @scope.new(path: merge_path_scope(@scope[:path], path))
+            yield
+          ensure
+            @scope = @scope.parent
+          end
 
-        def match_root_route(options)
-          name = has_named_route?(:root) ? nil : :root
-          match '/', { :as => name, :via => :get }.merge!(options)
-        end
+          def map_match(paths, options)
+            if options[:on] && !VALID_ON_OPTIONS.include?(options[:on])
+              raise ArgumentError, "Unknown scope #{on.inspect} given to :on"
+            end
+
+            if @scope[:to]
+              options[:to] ||= @scope[:to]
+            end
+
+            if @scope[:controller] && @scope[:action]
+              options[:to] ||= "#{@scope[:controller]}##{@scope[:action]}"
+            end
+
+            controller = options.delete(:controller) || @scope[:controller]
+            option_path = options.delete :path
+            to = options.delete :to
+            via = Mapping.check_via Array(options.delete(:via) {
+              @scope[:via]
+            })
+            formatted = options.delete(:format) { @scope[:format] }
+            anchor = options.delete(:anchor) { true }
+            options_constraints = options.delete(:constraints) || {}
+
+            path_types = paths.group_by(&:class)
+            path_types.fetch(String, []).each do |_path|
+              route_options = options.dup
+              if _path && option_path
+                raise ArgumentError, "Ambiguous route definition. Both :path and the route path were specified as strings."
+              end
+              to = get_to_from_path(_path, to, route_options[:action])
+              decomposed_match(_path, controller, route_options, _path, to, via, formatted, anchor, options_constraints)
+            end
+
+            path_types.fetch(Symbol, []).each do |action|
+              route_options = options.dup
+              decomposed_match(action, controller, route_options, option_path, to, via, formatted, anchor, options_constraints)
+            end
+
+            self
+          end
+
+          def get_to_from_path(path, to, action)
+            return to if to || action
+
+            path_without_format = path.sub(/\(\.:format\)$/, "")
+            if using_match_shorthand?(path_without_format)
+              path_without_format.gsub(%r{^/}, "").sub(%r{/([^/]*)$}, '#\1').tr("-", "_")
+            else
+              nil
+            end
+          end
+
+          def using_match_shorthand?(path)
+            path =~ %r{^/?[-\w]+/[-\w/]+$}
+          end
+
+          def decomposed_match(path, controller, options, _path, to, via, formatted, anchor, options_constraints)
+            if on = options.delete(:on)
+              send(on) { decomposed_match(path, controller, options, _path, to, via, formatted, anchor, options_constraints) }
+            else
+              case @scope.scope_level
+              when :resources
+                nested { decomposed_match(path, controller, options, _path, to, via, formatted, anchor, options_constraints) }
+              when :resource
+                member { decomposed_match(path, controller, options, _path, to, via, formatted, anchor, options_constraints) }
+              else
+                add_route(path, controller, options, _path, to, via, formatted, anchor, options_constraints)
+              end
+            end
+          end
+
+          def add_route(action, controller, options, _path, to, via, formatted, anchor, options_constraints)
+            path = path_for_action(action, _path)
+            raise ArgumentError, "path is required" if path.blank?
+
+            action = action.to_s
+
+            default_action = options.delete(:action) || @scope[:action]
+
+            if action =~ /^[\w\-\/]+$/
+              default_action ||= action.tr("-", "_") unless action.include?("/")
+            else
+              action = nil
+            end
+
+            as = if !options.fetch(:as, true) # if it's set to nil or false
+              options.delete(:as)
+            else
+              name_for_action(options.delete(:as), action)
+            end
+
+            path = Mapping.normalize_path URI.parser.escape(path), formatted
+            ast = Journey::Parser.parse path
+
+            mapping = Mapping.build(@scope, @set, ast, controller, default_action, to, via, formatted, options_constraints, anchor, options)
+            @set.add_route(mapping, as)
+          end
+
+          def match_root_route(options)
+            name = has_named_route?(name_for_action(:root, nil)) ? nil : :root
+            args = ["/", { as: name, via: :get }.merge!(options)]
+
+            match(*args)
+          end
       end
 
       # Routing Concerns allow you to declare common routes that can be reused
@@ -2001,7 +2028,7 @@ to this:
         #     concerns :commentable
         #   end
         #
-        # concerns also work in any routes helper that you want to use:
+        # Concerns also work in any routes helper that you want to use:
         #
         #   namespace :posts do
         #     concerns :commentable
@@ -2018,10 +2045,124 @@ to this:
         end
       end
 
+      module CustomUrls
+        # Define custom URL helpers that will be added to the application's
+        # routes. This allows you to override and/or replace the default behavior
+        # of routing helpers, e.g:
+        #
+        #   direct :homepage do
+        #     "http://www.rubyonrails.org"
+        #   end
+        #
+        #   direct :commentable do |model|
+        #     [ model, anchor: model.dom_id ]
+        #   end
+        #
+        #   direct :main do
+        #     { controller: "pages", action: "index", subdomain: "www" }
+        #   end
+        #
+        # The return value from the block passed to +direct+ must be a valid set of
+        # arguments for +url_for+ which will actually build the URL string. This can
+        # be one of the following:
+        #
+        # * A string, which is treated as a generated URL
+        # * A hash, e.g. <tt>{ controller: "pages", action: "index" }</tt>
+        # * An array, which is passed to +polymorphic_url+
+        # * An Active Model instance
+        # * An Active Model class
+        #
+        # NOTE: Other URL helpers can be called in the block but be careful not to invoke
+        # your custom URL helper again otherwise it will result in a stack overflow error.
+        #
+        # You can also specify default options that will be passed through to
+        # your URL helper definition, e.g:
+        #
+        #   direct :browse, page: 1, size: 10 do |options|
+        #     [ :products, options.merge(params.permit(:page, :size).to_h.symbolize_keys) ]
+        #   end
+        #
+        # In this instance the +params+ object comes from the context in which the the
+        # block is executed, e.g. generating a URL inside a controller action or a view.
+        # If the block is executed where there isn't a params object such as this:
+        #
+        #   Rails.application.routes.url_helpers.browse_path
+        #
+        # then it will raise a +NameError+. Because of this you need to be aware of the
+        # context in which you will use your custom URL helper when defining it.
+        #
+        # NOTE: The +direct+ method can't be used inside of a scope block such as
+        # +namespace+ or +scope+ and will raise an error if it detects that it is.
+        def direct(name, options = {}, &block)
+          unless @scope.root?
+            raise RuntimeError, "The direct method can't be used inside a routes scope block"
+          end
+
+          @set.add_url_helper(name, options, &block)
+        end
+
+        # Define custom polymorphic mappings of models to URLs. This alters the
+        # behavior of +polymorphic_url+ and consequently the behavior of
+        # +link_to+ and +form_for+ when passed a model instance, e.g:
+        #
+        #   resource :basket
+        #
+        #   resolve "Basket" do
+        #     [:basket]
+        #   end
+        #
+        # This will now generate "/basket" when a +Basket+ instance is passed to
+        # +link_to+ or +form_for+ instead of the standard "/baskets/:id".
+        #
+        # NOTE: This custom behavior only applies to simple polymorphic URLs where
+        # a single model instance is passed and not more complicated forms, e.g:
+        #
+        #   # config/routes.rb
+        #   resource :profile
+        #   namespace :admin do
+        #     resources :users
+        #   end
+        #
+        #   resolve("User") { [:profile] }
+        #
+        #   # app/views/application/_menu.html.erb
+        #   link_to "Profile", @current_user
+        #   link_to "Profile", [:admin, @current_user]
+        #
+        # The first +link_to+ will generate "/profile" but the second will generate
+        # the standard polymorphic URL of "/admin/users/1".
+        #
+        # You can pass options to a polymorphic mapping - the arity for the block
+        # needs to be two as the instance is passed as the first argument, e.g:
+        #
+        #   resolve "Basket", anchor: "items" do |basket, options|
+        #     [:basket, options]
+        #   end
+        #
+        # This generates the URL "/basket#items" because when the last item in an
+        # array passed to +polymorphic_url+ is a hash then it's treated as options
+        # to the URL helper that gets called.
+        #
+        # NOTE: The +resolve+ method can't be used inside of a scope block such as
+        # +namespace+ or +scope+ and will raise an error if it detects that it is.
+        def resolve(*args, &block)
+          unless @scope.root?
+            raise RuntimeError, "The resolve method can't be used inside a routes scope block"
+          end
+
+          options = args.extract_options!
+          args = args.flatten(1)
+
+          args.each do |klass|
+            @set.add_polymorphic_mapping(klass, options, &block)
+          end
+        end
+      end
+
       class Scope # :nodoc:
         OPTIONS = [:path, :shallow_path, :as, :shallow_prefix, :module,
                    :controller, :action, :path_names, :constraints,
-                   :shallow, :blocks, :defaults, :via, :format, :options]
+                   :shallow, :blocks, :defaults, :via, :format, :options, :to]
 
         RESOURCE_SCOPES = [:resource, :resources]
         RESOURCE_METHOD_SCOPES = [:collection, :member, :new]
@@ -2038,6 +2179,14 @@ to this:
           scope_level == :nested
         end
 
+        def null?
+          @hash.nil? && @parent.nil?
+        end
+
+        def root?
+          @parent.null?
+        end
+
         def resources?
           scope_level == :resources
         end
@@ -2101,7 +2250,7 @@ to this:
 
       def initialize(set) #:nodoc:
         @set = set
-        @scope = Scope.new({ :path_names => @set.resources_path_names })
+        @scope = Scope.new(path_names: @set.resources_path_names)
         @concerns = {}
       end
 
@@ -2111,6 +2260,7 @@ to this:
       include Scoping
       include Concerns
       include Resources
+      include CustomUrls
     end
   end
 end
diff --git a/actionpack/lib/action_dispatch/routing/polymorphic_routes.rb b/actionpack/lib/action_dispatch/routing/polymorphic_routes.rb
index 9934f5547a..6da869c0c2 100644
--- a/actionpack/lib/action_dispatch/routing/polymorphic_routes.rb
+++ b/actionpack/lib/action_dispatch/routing/polymorphic_routes.rb
@@ -1,10 +1,12 @@
+# frozen_string_literal: true
+
 module ActionDispatch
   module Routing
     # Polymorphic URL helpers are methods for smart resolution to a named route call when
     # given an Active Record model instance. They are to be used in combination with
     # ActionController::Resources.
     #
-    # These methods are useful when you want to generate correct URL or path to a RESTful
+    # These methods are useful when you want to generate the correct URL or path to a RESTful
     # resource without having to know the exact type of the record in question.
     #
     # Nested resources and/or namespaces are also supported, as illustrated in the example:
@@ -40,7 +42,7 @@ module ActionDispatch
     #
     # Example usage:
     #
-    #   edit_polymorphic_path(@post)              # => "/posts/1/edit"
+    #   edit_polymorphic_path(@post)           # => "/posts/1/edit"
     #   polymorphic_path(@post, format: :pdf)  # => "/posts/1.pdf"
     #
     # == Usage with mounted engines
@@ -79,7 +81,7 @@ module ActionDispatch
       #   polymorphic_url([blog, post], anchor: 'my_anchor', script_name: "/my_app")
       #     # => "http://example.com/my_app/blogs/1/posts/1#my_anchor"
       #
-      # For all of these options, see the documentation for <tt>url_for</tt>.
+      # For all of these options, see the documentation for {url_for}[rdoc-ref:ActionDispatch::Routing::UrlFor].
       #
       # ==== Functionality
       #
@@ -103,6 +105,10 @@ module ActionDispatch
           return polymorphic_url record, options
         end
 
+        if mapping = polymorphic_mapping(record_or_hash_or_array)
+          return mapping.call(self, [record_or_hash_or_array, options], false)
+        end
+
         opts   = options.dup
         action = opts.delete :action
         type   = opts.delete(:routing_type) || :url
@@ -123,6 +129,10 @@ module ActionDispatch
           return polymorphic_path record, options
         end
 
+        if mapping = polymorphic_mapping(record_or_hash_or_array)
+          return mapping.call(self, [record_or_hash_or_array, options], true)
+        end
+
         opts   = options.dup
         action = opts.delete :action
         type   = :path
@@ -134,7 +144,6 @@ module ActionDispatch
                                                opts
       end
 
-
       %w(edit new).each do |action|
         module_eval <<-EOT, __FILE__, __LINE__ + 1
           def #{action}_polymorphic_url(record_or_hash, options = {})
@@ -149,176 +158,195 @@ module ActionDispatch
 
       private
 
-      def polymorphic_url_for_action(action, record_or_hash, options)
-        polymorphic_url(record_or_hash, options.merge(:action => action))
-      end
-
-      def polymorphic_path_for_action(action, record_or_hash, options)
-        polymorphic_path(record_or_hash, options.merge(:action => action))
-      end
-
-      class HelperMethodBuilder # :nodoc:
-        CACHE = { 'path' => {}, 'url' => {} }
-
-        def self.get(action, type)
-          type   = type.to_s
-          CACHE[type].fetch(action) { build action, type }
+        def polymorphic_url_for_action(action, record_or_hash, options)
+          polymorphic_url(record_or_hash, options.merge(action: action))
         end
 
-        def self.url;  CACHE['url'.freeze][nil]; end
-        def self.path; CACHE['path'.freeze][nil]; end
+        def polymorphic_path_for_action(action, record_or_hash, options)
+          polymorphic_path(record_or_hash, options.merge(action: action))
+        end
 
-        def self.build(action, type)
-          prefix = action ? "#{action}_" : ""
-          suffix = type
-          if action.to_s == 'new'
-            HelperMethodBuilder.singular prefix, suffix
+        def polymorphic_mapping(record)
+          if record.respond_to?(:to_model)
+            _routes.polymorphic_mappings[record.to_model.model_name.name]
           else
-            HelperMethodBuilder.plural prefix, suffix
+            _routes.polymorphic_mappings[record.class.name]
           end
         end
 
-        def self.singular(prefix, suffix)
-          new(->(name) { name.singular_route_key }, prefix, suffix)
-        end
+        class HelperMethodBuilder # :nodoc:
+          CACHE = { "path" => {}, "url" => {} }
 
-        def self.plural(prefix, suffix)
-          new(->(name) { name.route_key }, prefix, suffix)
-        end
+          def self.get(action, type)
+            type = type.to_s
+            CACHE[type].fetch(action) { build action, type }
+          end
 
-        def self.polymorphic_method(recipient, record_or_hash_or_array, action, type, options)
-          builder = get action, type
+          def self.url;  CACHE["url".freeze][nil]; end
+          def self.path; CACHE["path".freeze][nil]; end
 
-          case record_or_hash_or_array
-          when Array
-            record_or_hash_or_array = record_or_hash_or_array.compact
-            if record_or_hash_or_array.empty?
-              raise ArgumentError, "Nil location provided. Can't build URI."
-            end
-            if record_or_hash_or_array.first.is_a?(ActionDispatch::Routing::RoutesProxy)
-              recipient = record_or_hash_or_array.shift
+          def self.build(action, type)
+            prefix = action ? "#{action}_" : ""
+            suffix = type
+            if action.to_s == "new"
+              HelperMethodBuilder.singular prefix, suffix
+            else
+              HelperMethodBuilder.plural prefix, suffix
             end
-
-            method, args = builder.handle_list record_or_hash_or_array
-          when String, Symbol
-            method, args = builder.handle_string record_or_hash_or_array
-          when Class
-            method, args = builder.handle_class record_or_hash_or_array
-
-          when nil
-            raise ArgumentError, "Nil location provided. Can't build URI."
-          else
-            method, args = builder.handle_model record_or_hash_or_array
           end
 
+          def self.singular(prefix, suffix)
+            new(->(name) { name.singular_route_key }, prefix, suffix)
+          end
 
-          if options.empty?
-            recipient.send(method, *args)
-          else
-            recipient.send(method, *args, options)
+          def self.plural(prefix, suffix)
+            new(->(name) { name.route_key }, prefix, suffix)
           end
-        end
 
-        attr_reader :suffix, :prefix
+          def self.polymorphic_method(recipient, record_or_hash_or_array, action, type, options)
+            builder = get action, type
+
+            case record_or_hash_or_array
+            when Array
+              record_or_hash_or_array = record_or_hash_or_array.compact
+              if record_or_hash_or_array.empty?
+                raise ArgumentError, "Nil location provided. Can't build URI."
+              end
+              if record_or_hash_or_array.first.is_a?(ActionDispatch::Routing::RoutesProxy)
+                recipient = record_or_hash_or_array.shift
+              end
+
+              method, args = builder.handle_list record_or_hash_or_array
+            when String, Symbol
+              method, args = builder.handle_string record_or_hash_or_array
+            when Class
+              method, args = builder.handle_class record_or_hash_or_array
 
-        def initialize(key_strategy, prefix, suffix)
-          @key_strategy = key_strategy
-          @prefix       = prefix
-          @suffix       = suffix
-        end
+            when nil
+              raise ArgumentError, "Nil location provided. Can't build URI."
+            else
+              method, args = builder.handle_model record_or_hash_or_array
+            end
 
-        def handle_string(record)
-          [get_method_for_string(record), []]
-        end
+            if options.empty?
+              recipient.send(method, *args)
+            else
+              recipient.send(method, *args, options)
+            end
+          end
 
-        def handle_string_call(target, str)
-          target.send get_method_for_string str
-        end
+          attr_reader :suffix, :prefix
 
-        def handle_class(klass)
-          [get_method_for_class(klass), []]
-        end
+          def initialize(key_strategy, prefix, suffix)
+            @key_strategy = key_strategy
+            @prefix       = prefix
+            @suffix       = suffix
+          end
 
-        def handle_class_call(target, klass)
-          target.send get_method_for_class klass
-        end
+          def handle_string(record)
+            [get_method_for_string(record), []]
+          end
 
-        def handle_model(record)
-          args  = []
+          def handle_string_call(target, str)
+            target.send get_method_for_string str
+          end
 
-          model = record.to_model
-          named_route = if model.persisted?
-                          args << model
-                          get_method_for_string model.model_name.singular_route_key
-                        else
-                          get_method_for_class model
-                        end
+          def handle_class(klass)
+            [get_method_for_class(klass), []]
+          end
 
-          [named_route, args]
-        end
+          def handle_class_call(target, klass)
+            target.send get_method_for_class klass
+          end
 
-        def handle_model_call(target, model)
-          method, args = handle_model model
-          target.send(method, *args)
-        end
+          def handle_model(record)
+            args  = []
 
-        def handle_list(list)
-          record_list = list.dup
-          record      = record_list.pop
+            model = record.to_model
+            named_route = if model.persisted?
+              args << model
+              get_method_for_string model.model_name.singular_route_key
+            else
+              get_method_for_class model
+            end
 
-          args = []
+            [named_route, args]
+          end
 
-          route  = record_list.map { |parent|
-            case parent
-            when Symbol, String
-              parent.to_s
-            when Class
-              args << parent
-              parent.model_name.singular_route_key
+          def handle_model_call(target, record)
+            if mapping = polymorphic_mapping(target, record)
+              mapping.call(target, [record], suffix == "path")
             else
-              args << parent.to_model
-              parent.to_model.model_name.singular_route_key
+              method, args = handle_model(record)
+              target.send(method, *args)
             end
-          }
-
-          route <<
-          case record
-          when Symbol, String
-            record.to_s
-          when Class
-            @key_strategy.call record.model_name
-          else
-            model = record.to_model
-            if model.persisted?
-              args << model
-              model.model_name.singular_route_key
+          end
+
+          def handle_list(list)
+            record_list = list.dup
+            record      = record_list.pop
+
+            args = []
+
+            route = record_list.map { |parent|
+              case parent
+              when Symbol, String
+                parent.to_s
+              when Class
+                args << parent
+                parent.model_name.singular_route_key
+              else
+                args << parent.to_model
+                parent.to_model.model_name.singular_route_key
+              end
+            }
+
+            route <<
+            case record
+            when Symbol, String
+              record.to_s
+            when Class
+              @key_strategy.call record.model_name
             else
-              @key_strategy.call model.model_name
+              model = record.to_model
+              if model.persisted?
+                args << model
+                model.model_name.singular_route_key
+              else
+                @key_strategy.call model.model_name
+              end
             end
-          end
 
-          route << suffix
+            route << suffix
 
-          named_route = prefix + route.join("_")
-          [named_route, args]
-        end
+            named_route = prefix + route.join("_")
+            [named_route, args]
+          end
 
-        private
+          private
 
-        def get_method_for_class(klass)
-          name   = @key_strategy.call klass.model_name
-          get_method_for_string name
-        end
+            def polymorphic_mapping(target, record)
+              if record.respond_to?(:to_model)
+                target._routes.polymorphic_mappings[record.to_model.model_name.name]
+              else
+                target._routes.polymorphic_mappings[record.class.name]
+              end
+            end
 
-        def get_method_for_string(str)
-          "#{prefix}#{str}_#{suffix}"
-        end
+            def get_method_for_class(klass)
+              name = @key_strategy.call klass.model_name
+              get_method_for_string name
+            end
 
-        [nil, 'new', 'edit'].each do |action|
-          CACHE['url'][action]  = build action, 'url'
-          CACHE['path'][action] = build action, 'path'
+            def get_method_for_string(str)
+              "#{prefix}#{str}_#{suffix}"
+            end
+
+            [nil, "new", "edit"].each do |action|
+              CACHE["url"][action]  = build action, "url"
+              CACHE["path"][action] = build action, "path"
+            end
         end
-      end
     end
   end
 end
diff --git a/actionpack/lib/action_dispatch/routing/redirection.rb b/actionpack/lib/action_dispatch/routing/redirection.rb
index d6987f4d09..143a4b3d62 100644
--- a/actionpack/lib/action_dispatch/routing/redirection.rb
+++ b/actionpack/lib/action_dispatch/routing/redirection.rb
@@ -1,9 +1,11 @@
-require 'action_dispatch/http/request'
-require 'active_support/core_ext/uri'
-require 'active_support/core_ext/array/extract_options'
-require 'rack/utils'
-require 'action_controller/metal/exceptions'
-require 'action_dispatch/routing/endpoint'
+# frozen_string_literal: true
+
+require "action_dispatch/http/request"
+require "active_support/core_ext/uri"
+require "active_support/core_ext/array/extract_options"
+require "rack/utils"
+require "action_controller/metal/exceptions"
+require "action_dispatch/routing/endpoint"
 
 module ActionDispatch
   module Routing
@@ -22,7 +24,6 @@ module ActionDispatch
       end
 
       def serve(req)
-        req.check_path_parameters!
         uri = URI.parse(path(req.path_parameters, req))
 
         unless uri.host
@@ -37,12 +38,14 @@ module ActionDispatch
         uri.host   ||= req.host
         uri.port   ||= req.port unless req.standard_port?
 
+        req.commit_flash
+
         body = %(<html><body>You are being <a href="#{ERB::Util.unwrapped_html_escape(uri.to_s)}">redirected</a>.</body></html>)
 
         headers = {
-          'Location' => uri.to_s,
-          'Content-Type' => 'text/html',
-          'Content-Length' => body.length.to_s
+          "Location" => uri.to_s,
+          "Content-Type" => "text/html",
+          "Content-Length" => body.length.to_s
         }
 
         [ status, headers, [body] ]
@@ -58,19 +61,19 @@ module ActionDispatch
 
       private
         def relative_path?(path)
-          path && !path.empty? && path[0] != '/'
+          path && !path.empty? && path[0] != "/"
         end
 
         def escape(params)
-          Hash[params.map{ |k,v| [k, Rack::Utils.escape(v)] }]
+          Hash[params.map { |k, v| [k, Rack::Utils.escape(v)] }]
         end
 
         def escape_fragment(params)
-          Hash[params.map{ |k,v| [k, Journey::Router::Utils.escape_fragment(v)] }]
+          Hash[params.map { |k, v| [k, Journey::Router::Utils.escape_fragment(v)] }]
         end
 
         def escape_path(params)
-          Hash[params.map{ |k,v| [k, Journey::Router::Utils.escape_path(v)] }]
+          Hash[params.map { |k, v| [k, Journey::Router::Utils.escape_path(v)] }]
         end
     end
 
@@ -104,11 +107,11 @@ module ActionDispatch
 
       def path(params, request)
         url_options = {
-          :protocol => request.protocol,
-          :host     => request.host,
-          :port     => request.optional_port,
-          :path     => request.path,
-          :params   => request.query_parameters
+          protocol: request.protocol,
+          host: request.host,
+          port: request.optional_port,
+          path: request.path,
+          params: request.query_parameters
         }.merge! options
 
         if !params.empty? && url_options[:path].match(/%\{\w*\}/)
@@ -129,21 +132,23 @@ module ActionDispatch
       end
 
       def inspect
-        "redirect(#{status}, #{options.map{ |k,v| "#{k}: #{v}" }.join(', ')})"
+        "redirect(#{status}, #{options.map { |k, v| "#{k}: #{v}" }.join(', ')})"
       end
     end
 
     module Redirection
-
       # Redirect any path to another path:
       #
       #   get "/stories" => redirect("/posts")
       #
+      # This will redirect the user, while ignoring certain parts of the request, including query string, etc.
+      # <tt>/stories</tt>, <tt>/stories?foo=bar</tt>, etc all redirect to <tt>/posts</tt>.
+      #
       # You can also use interpolation in the supplied redirect argument:
       #
       #   get 'docs/:article', to: redirect('/wiki/%{article}')
       #
-      # Note that if you return a path without a leading slash then the url is prefixed with the
+      # Note that if you return a path without a leading slash then the URL is prefixed with the
       # current SCRIPT_NAME environment variable. This is typically '/' but may be different in
       # a mounted engine or where the application is deployed to a subdirectory of a website.
       #
@@ -162,11 +167,16 @@ module ActionDispatch
       # Note that the +do end+ syntax for the redirect block wouldn't work, as Ruby would pass
       # the block to +get+ instead of +redirect+. Use <tt>{ ... }</tt> instead.
       #
-      # The options version of redirect allows you to supply only the parts of the url which need
+      # The options version of redirect allows you to supply only the parts of the URL which need
       # to change, it also supports interpolation of the path similar to the first example.
       #
       #   get 'stores/:name',       to: redirect(subdomain: 'stores', path: '/%{name}')
       #   get 'stores/:name(*all)', to: redirect(subdomain: 'stores', path: '/%{name}%{all}')
+      #   get '/stories', to: redirect(path: '/posts')
+      #
+      # This will redirect the user, while changing only the specified parts of the request,
+      # for example the +path+ option in the last example.
+      # <tt>/stories</tt>, <tt>/stories?foo=bar</tt>, redirect to <tt>/posts</tt> and <tt>/posts?foo=bar</tt> respectively.
       #
       # Finally, an object which responds to call can be supplied to redirect, allowing you to reuse
       # common redirect routes. The call method must accept two arguments, params and request, and return
diff --git a/actionpack/lib/action_dispatch/routing/route_set.rb b/actionpack/lib/action_dispatch/routing/route_set.rb
index ed7130b58e..9eff30fa53 100644
--- a/actionpack/lib/action_dispatch/routing/route_set.rb
+++ b/actionpack/lib/action_dispatch/routing/route_set.rb
@@ -1,12 +1,14 @@
-require 'action_dispatch/journey'
-require 'active_support/concern'
-require 'active_support/core_ext/object/to_query'
-require 'active_support/core_ext/hash/slice'
-require 'active_support/core_ext/module/remove_method'
-require 'active_support/core_ext/array/extract_options'
-require 'action_controller/metal/exceptions'
-require 'action_dispatch/http/request'
-require 'action_dispatch/routing/endpoint'
+# frozen_string_literal: true
+
+require "action_dispatch/journey"
+require "active_support/core_ext/object/to_query"
+require "active_support/core_ext/hash/slice"
+require "active_support/core_ext/module/redefine_method"
+require "active_support/core_ext/module/remove_method"
+require "active_support/core_ext/array/extract_options"
+require "action_controller/metal/exceptions"
+require "action_dispatch/http/request"
+require "action_dispatch/routing/endpoint"
 
 module ActionDispatch
   module Routing
@@ -34,7 +36,7 @@ module ActionDispatch
           if @raise_on_name_error
             raise
           else
-            return [404, {'X-Cascade' => 'pass'}, []]
+            return [404, { "X-Cascade" => "pass" }, []]
           end
         end
 
@@ -59,7 +61,7 @@ module ActionDispatch
 
         private
 
-        def controller(_); @controller_class; end
+          def controller(_); @controller_class; end
       end
 
       # A NamedRouteCollection instance is a collection of named routes, and also
@@ -71,7 +73,7 @@ module ActionDispatch
         private :routes
 
         def initialize
-          @routes  = {}
+          @routes = {}
           @path_helpers = Set.new
           @url_helpers = Set.new
           @url_helpers_module  = Module.new
@@ -89,11 +91,11 @@ module ActionDispatch
 
         def clear!
           @path_helpers.each do |helper|
-            @path_helpers_module.send :undef_method, helper
+            @path_helpers_module.send :remove_method, helper
           end
 
           @url_helpers.each do |helper|
-            @url_helpers_module.send  :undef_method, helper
+            @url_helpers_module.send  :remove_method, helper
           end
 
           @routes.clear
@@ -144,6 +146,31 @@ module ActionDispatch
           routes.length
         end
 
+        # Given a +name+, defines name_path and name_url helpers.
+        # Used by 'direct', 'resolve', and 'polymorphic' route helpers.
+        def add_url_helper(name, defaults, &block)
+          helper = CustomUrlHelper.new(name, defaults, &block)
+          path_name = :"#{name}_path"
+          url_name = :"#{name}_url"
+
+          @path_helpers_module.module_eval do
+            define_method(path_name) do |*args|
+              helper.call(self, args, true)
+            end
+          end
+
+          @url_helpers_module.module_eval do
+            define_method(url_name) do |*args|
+              helper.call(self, args, false)
+            end
+          end
+
+          @path_helpers << path_name
+          @url_helpers << url_name
+
+          self
+        end
+
         class UrlHelper
           def self.create(route, options, route_name, url_strategy)
             if optimize_helper?(route)
@@ -172,6 +199,16 @@ module ActionDispatch
               if args.size == arg_size && !inner_options && optimize_routes_generation?(t)
                 options = t.url_options.merge @options
                 options[:path] = optimized_helper(args)
+
+                original_script_name = options.delete(:original_script_name)
+                script_name = t._routes.find_script_name(options)
+
+                if original_script_name
+                  script_name = original_script_name + script_name
+                end
+
+                options[:script_name] = script_name
+
                 url_strategy.call options
               else
                 super
@@ -180,40 +217,40 @@ module ActionDispatch
 
             private
 
-            def optimized_helper(args)
-              params = parameterize_args(args) do
-                raise_generation_error(args)
-              end
+              def optimized_helper(args)
+                params = parameterize_args(args) do
+                  raise_generation_error(args)
+                end
 
-              @route.format params
-            end
+                @route.format params
+              end
 
-            def optimize_routes_generation?(t)
-              t.send(:optimize_routes_generation?)
-            end
+              def optimize_routes_generation?(t)
+                t.send(:optimize_routes_generation?)
+              end
 
-            def parameterize_args(args)
-              params = {}
-              @arg_size.times { |i|
-                key = @required_parts[i]
-                value = args[i].to_param
-                yield key if value.nil? || value.empty?
-                params[key] = value
-              }
-              params
-            end
+              def parameterize_args(args)
+                params = {}
+                @arg_size.times { |i|
+                  key = @required_parts[i]
+                  value = args[i].to_param
+                  yield key if value.nil? || value.empty?
+                  params[key] = value
+                }
+                params
+              end
 
-            def raise_generation_error(args)
-              missing_keys = []
-              params = parameterize_args(args) { |missing_key|
-                missing_keys << missing_key
-              }
-              constraints = Hash[@route.requirements.merge(params).sort_by{|k,v| k.to_s}]
-              message = "No route matches #{constraints.inspect}"
-              message << " missing required keys: #{missing_keys.sort.inspect}"
+              def raise_generation_error(args)
+                missing_keys = []
+                params = parameterize_args(args) { |missing_key|
+                  missing_keys << missing_key
+                }
+                constraints = Hash[@route.requirements.merge(params).sort_by { |k, v| k.to_s }]
+                message = "No route matches #{constraints.inspect}".dup
+                message << ", missing required keys: #{missing_keys.sort.inspect}"
 
-              raise ActionController::UrlGenerationError, message
-            end
+                raise ActionController::UrlGenerationError, message
+              end
           end
 
           def initialize(route, options, route_name, url_strategy)
@@ -248,6 +285,8 @@ module ActionDispatch
               if args.size < path_params_size
                 path_params -= controller_options.keys
                 path_params -= result.keys
+              else
+                path_params = path_params.dup
               end
               inner_options.each_key do |key|
                 path_params.delete(key)
@@ -264,38 +303,35 @@ module ActionDispatch
         end
 
         private
-        # Create a url helper allowing ordered parameters to be associated
-        # with corresponding dynamic segments, so you can do:
-        #
-        #   foo_url(bar, baz, bang)
-        #
-        # Instead of:
-        #
-        #   foo_url(bar: bar, baz: baz, bang: bang)
-        #
-        # Also allow options hash, so you can do:
-        #
-        #   foo_url(bar, baz, bang, sort_by: 'baz')
-        #
-        def define_url_helper(mod, route, name, opts, route_key, url_strategy)
-          helper = UrlHelper.create(route, opts, route_key, url_strategy)
-          mod.module_eval do
-            define_method(name) do |*args|
-              last = args.last
-              options = case last
-                        when Hash
-                          args.pop
-                        when ActionController::Parameters
-                          if last.permitted?
-                            args.pop.to_h
-                          else
-                            raise ArgumentError, ActionDispatch::Routing::INSECURE_URL_PARAMETERS_MESSAGE
-                          end
-                        end
-              helper.call self, args, options
+          # Create a URL helper allowing ordered parameters to be associated
+          # with corresponding dynamic segments, so you can do:
+          #
+          #   foo_url(bar, baz, bang)
+          #
+          # Instead of:
+          #
+          #   foo_url(bar: bar, baz: baz, bang: bang)
+          #
+          # Also allow options hash, so you can do:
+          #
+          #   foo_url(bar, baz, bang, sort_by: 'baz')
+          #
+          def define_url_helper(mod, route, name, opts, route_key, url_strategy)
+            helper = UrlHelper.create(route, opts, route_key, url_strategy)
+            mod.module_eval do
+              define_method(name) do |*args|
+                last = args.last
+                options = \
+                  case last
+                  when Hash
+                    args.pop
+                  when ActionController::Parameters
+                    args.pop.to_h
+                  end
+                helper.call self, args, options
+              end
             end
           end
-        end
       end
 
       # strategy for building urls to send to the client
@@ -305,12 +341,12 @@ module ActionDispatch
       attr_accessor :formatter, :set, :named_routes, :default_scope, :router
       attr_accessor :disable_clear_and_finalize, :resources_path_names
       attr_accessor :default_url_options
-      attr_reader :env_key
+      attr_reader :env_key, :polymorphic_mappings
 
       alias :routes :set
 
       def self.default_resources_path_names
-        { :new => 'new', :edit => 'edit' }
+        { new: "new", edit: "edit" }
       end
 
       def self.new_with_config(config)
@@ -347,6 +383,13 @@ module ActionDispatch
         @set    = Journey::Routes.new
         @router = Journey::Router.new @set
         @formatter = Journey::Formatter.new self
+        @polymorphic_mappings = {}
+      end
+
+      def eager_load!
+        router.eager_load!
+        routes.each(&:eager_load!)
+        nil
       end
 
       def relative_url_root
@@ -402,6 +445,7 @@ module ActionDispatch
         named_routes.clear
         set.clear
         formatter.clear
+        @polymorphic_mappings.clear
         @prepend.each { |blk| eval_block(blk) }
       end
 
@@ -418,7 +462,7 @@ module ActionDispatch
         MountedHelpers
       end
 
-      def define_mounted_helper(name)
+      def define_mounted_helper(name, script_namer = nil)
         return if MountedHelpers.method_defined?(name)
 
         routes = self
@@ -426,7 +470,7 @@ module ActionDispatch
 
         MountedHelpers.class_eval do
           define_method "_#{name}" do
-            RoutesProxy.new(routes, _routes_context, helpers)
+            RoutesProxy.new(routes, _routes_context, helpers, script_namer)
           end
         end
 
@@ -446,17 +490,50 @@ module ActionDispatch
 
           # Define url_for in the singleton level so one can do:
           # Rails.application.routes.url_helpers.url_for(args)
-          @_routes = routes
+          proxy_class = Class.new do
+            include UrlFor
+            include routes.named_routes.path_helpers_module
+            include routes.named_routes.url_helpers_module
+
+            attr_reader :_routes
+
+            def initialize(routes)
+              @_routes = routes
+            end
+
+            def optimize_routes_generation?
+              @_routes.optimize_routes_generation?
+            end
+          end
+
+          @_proxy = proxy_class.new(routes)
+
           class << self
             def url_for(options)
-              @_routes.url_for(options)
+              @_proxy.url_for(options)
+            end
+
+            def full_url_for(options)
+              @_proxy.full_url_for(options)
+            end
+
+            def route_for(name, *args)
+              @_proxy.route_for(name, *args)
             end
 
             def optimize_routes_generation?
-              @_routes.optimize_routes_generation?
+              @_proxy.optimize_routes_generation?
             end
 
-            attr_reader :_routes
+            def polymorphic_url(record_or_hash_or_array, options = {})
+              @_proxy.polymorphic_url(record_or_hash_or_array, options)
+            end
+
+            def polymorphic_path(record_or_hash_or_array, options = {})
+              @_proxy.polymorphic_path(record_or_hash_or_array, options)
+            end
+
+            def _routes; @_proxy._routes; end
             def url_options; {}; end
           end
 
@@ -480,7 +557,7 @@ module ActionDispatch
 
           # plus a singleton class method called _routes ...
           included do
-            singleton_class.send(:redefine_method, :_routes) { routes }
+            redefine_singleton_method(:_routes) { routes }
           end
 
           # And an instance method _routes. Note that
@@ -500,7 +577,7 @@ module ActionDispatch
         routes.empty?
       end
 
-      def add_route(mapping, path_ast, name, anchor)
+      def add_route(mapping, name)
         raise ArgumentError, "Invalid route name: '#{name}'" unless name.blank? || name.to_s.match(/^[_a-z]\w*$/i)
 
         if name && named_routes[name]
@@ -517,20 +594,58 @@ module ActionDispatch
         if route.segment_keys.include?(:controller)
           ActiveSupport::Deprecation.warn(<<-MSG.squish)
             Using a dynamic :controller segment in a route is deprecated and
-            will be removed in Rails 5.1.
+            will be removed in Rails 6.0.
           MSG
         end
 
         if route.segment_keys.include?(:action)
           ActiveSupport::Deprecation.warn(<<-MSG.squish)
             Using a dynamic :action segment in a route is deprecated and
-            will be removed in Rails 5.1.
+            will be removed in Rails 6.0.
           MSG
         end
 
         route
       end
 
+      def add_polymorphic_mapping(klass, options, &block)
+        @polymorphic_mappings[klass] = CustomUrlHelper.new(klass, options, &block)
+      end
+
+      def add_url_helper(name, options, &block)
+        named_routes.add_url_helper(name, options, &block)
+      end
+
+      class CustomUrlHelper
+        attr_reader :name, :defaults, :block
+
+        def initialize(name, defaults, &block)
+          @name = name
+          @defaults = defaults
+          @block = block
+        end
+
+        def call(t, args, only_path = false)
+          options = args.extract_options!
+          url = t.full_url_for(eval_block(t, args, options))
+
+          if only_path
+            "/" + url.partition(%r{(?<!/)/(?!/)}).last
+          else
+            url
+          end
+        end
+
+        private
+          def eval_block(t, args, options)
+            t.instance_exec(*args, merge_defaults(options), &block)
+          end
+
+          def merge_defaults(options)
+            defaults ? defaults.merge(options) : options
+          end
+      end
+
       class Generator
         PARAMETERIZE = lambda do |name, value|
           if name == :controller
@@ -581,12 +696,12 @@ module ActionDispatch
           # be "index", not the recalled action of "show".
 
           if options[:controller]
-            options[:action]     ||= 'index'
+            options[:action]     ||= "index"
             options[:controller]   = options[:controller].to_s
           end
 
           if options.key?(:action)
-            options[:action] = (options[:action] || 'index').to_s
+            options[:action] = (options[:action] || "index").to_s
           end
         end
 
@@ -596,8 +711,8 @@ module ActionDispatch
         # :controller, :action or :id is not found, don't pull any
         # more keys from the recall.
         def normalize_controller_action_id!
-          use_recall_for(:controller) or return
-          use_recall_for(:action) or return
+          use_recall_for(:controller) || return
+          use_recall_for(:action) || return
           use_recall_for(:id)
         end
 
@@ -605,7 +720,7 @@ module ActionDispatch
         # is specified, the controller becomes "foo/baz/bat"
         def use_relative_controller!
           if !named_route && different_controller? && !controller.start_with?("/")
-            old_parts = current_controller.split('/')
+            old_parts = current_controller.split("/")
             size = controller.count("/") + 1
             parts = old_parts[0...-size] << controller
             @options[:controller] = parts.join("/")
@@ -646,11 +761,11 @@ module ActionDispatch
 
       # Generate the path indicated by the arguments, and return an array of
       # the keys that were not used to generate it.
-      def extra_keys(options, recall={})
+      def extra_keys(options, recall = {})
         generate_extras(options, recall).last
       end
 
-      def generate_extras(options, recall={})
+      def generate_extras(options, recall = {})
         route_key = options.delete :use_route
         path, params = generate(route_key, options, recall)
         return path, params.keys
@@ -670,7 +785,7 @@ module ActionDispatch
       end
 
       def find_script_name(options)
-        options.delete(:script_name) || find_relative_url_root(options) || ''
+        options.delete(:script_name) || find_relative_url_root(options) || ""
       end
 
       def find_relative_url_root(options)
@@ -692,7 +807,7 @@ module ActionDispatch
           password = options.delete :password
         end
 
-        recall  = options.delete(:_recall) { {} }
+        recall = options.delete(:_recall) { {} }
 
         original_script_name = options.delete(:original_script_name)
         script_name = find_script_name options
@@ -731,12 +846,16 @@ module ActionDispatch
         extras = environment[:extras] || {}
 
         begin
-          env = Rack::MockRequest.env_for(path, {:method => method})
+          env = Rack::MockRequest.env_for(path, method: method)
         rescue URI::InvalidURIError => e
           raise ActionController::RoutingError, e.message
         end
 
         req = make_request(env)
+        recognize_path_with_request(req, path, extras)
+      end
+
+      def recognize_path_with_request(req, path, extras)
         @router.recognize(req) do |route, params|
           params.merge!(extras)
           params.each do |key, value|
@@ -745,8 +864,7 @@ module ActionDispatch
               params[key] = URI.parser.unescape(value)
             end
           end
-          old_params = req.path_parameters
-          req.path_parameters = old_params.merge params
+          req.path_parameters = params
           app = route.app
           if app.matches?(req) && app.dispatcher?
             begin
@@ -756,6 +874,9 @@ module ActionDispatch
             end
 
             return req.path_parameters
+          elsif app.matches?(req) && app.engine?
+            path_parameters = app.rack_app.routes.recognize_path_with_request(req, path, extras)
+            return path_parameters
           end
         end
 
diff --git a/actionpack/lib/action_dispatch/routing/routes_proxy.rb b/actionpack/lib/action_dispatch/routing/routes_proxy.rb
index 040ea04046..587a72729c 100644
--- a/actionpack/lib/action_dispatch/routing/routes_proxy.rb
+++ b/actionpack/lib/action_dispatch/routing/routes_proxy.rb
@@ -1,4 +1,6 @@
-require 'active_support/core_ext/array/extract_options'
+# frozen_string_literal: true
+
+require "active_support/core_ext/array/extract_options"
 
 module ActionDispatch
   module Routing
@@ -8,9 +10,10 @@ module ActionDispatch
       attr_accessor :scope, :routes
       alias :_routes :routes
 
-      def initialize(routes, scope, helpers)
+      def initialize(routes, scope, helpers, script_namer = nil)
         @routes, @scope = routes, scope
         @helpers = helpers
+        @script_namer = script_namer
       end
 
       def url_options
@@ -19,7 +22,8 @@ module ActionDispatch
         end
       end
 
-      def respond_to?(method, include_private = false)
+    private
+      def respond_to_missing?(method, _)
         super || @helpers.respond_to?(method)
       end
 
@@ -28,15 +32,38 @@ module ActionDispatch
           self.class.class_eval <<-RUBY, __FILE__, __LINE__ + 1
             def #{method}(*args)
               options = args.extract_options!
-              args << url_options.merge((options || {}).symbolize_keys)
+              options = url_options.merge((options || {}).symbolize_keys)
+
+              if @script_namer
+                options[:script_name] = merge_script_names(
+                  options[:script_name],
+                  @script_namer.call(options)
+                )
+              end
+
+              args << options
               @helpers.#{method}(*args)
             end
           RUBY
-          send(method, *args)
+          public_send(method, *args)
         else
           super
         end
       end
+
+      # Keeps the part of the script name provided by the global
+      # context via ENV["SCRIPT_NAME"], which `mount` doesn't know
+      # about since it depends on the specific request, but use our
+      # script name resolver for the mount point dependent part.
+      def merge_script_names(previous_script_name, new_script_name)
+        return new_script_name unless previous_script_name
+
+        resolved_parts = new_script_name.count("/")
+        previous_parts = previous_script_name.count("/")
+        context_parts = previous_parts - resolved_parts + 1
+
+        (previous_script_name.split("/").slice(0, context_parts).join("/")) + new_script_name
+      end
     end
   end
 end
diff --git a/actionpack/lib/action_dispatch/routing/url_for.rb b/actionpack/lib/action_dispatch/routing/url_for.rb
index 5ee138e6c6..fa345dccdf 100644
--- a/actionpack/lib/action_dispatch/routing/url_for.rb
+++ b/actionpack/lib/action_dispatch/routing/url_for.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActionDispatch
   module Routing
     # In <tt>config/routes.rb</tt> you define URL-to-controller mappings, but the reverse
@@ -107,16 +109,16 @@ module ActionDispatch
       end
 
       # Hook overridden in controller to add request information
-      # with `default_url_options`. Application logic should not
+      # with +default_url_options+. Application logic should not
       # go into url_options.
       def url_options
         default_url_options
       end
 
-      # Generate a url based on the options provided, default_url_options and the
+      # Generate a URL based on the options provided, default_url_options and the
       # routes defined in routes.rb. The following options are supported:
       #
-      # * <tt>:only_path</tt> - If true, the relative url is returned. Defaults to +false+.
+      # * <tt>:only_path</tt> - If true, the relative URL is returned. Defaults to +false+.
       # * <tt>:protocol</tt> - The protocol to connect to. Defaults to 'http'.
       # * <tt>:host</tt> - Specifies the host the link should be targeted at.
       #   If <tt>:only_path</tt> is false, this option must be
@@ -153,7 +155,7 @@ module ActionDispatch
       # Missing routes keys may be filled in from the current request's parameters
       # (e.g. +:controller+, +:action+, +:id+ and any other parameters that are
       # placed in the path). Given that the current action has been reached
-      # through `GET /users/1`:
+      # through <tt>GET /users/1</tt>:
       #
       #   url_for(only_path: true)                        # => '/users/1'
       #   url_for(only_path: true, action: 'edit')        # => '/users/1/edit'
@@ -164,20 +166,17 @@ module ActionDispatch
       # implicitly used by +url_for+ can always be overwritten like shown on the
       # last +url_for+ calls.
       def url_for(options = nil)
+        full_url_for(options)
+      end
+
+      def full_url_for(options = nil) # :nodoc:
         case options
         when nil
           _routes.url_for(url_options.symbolize_keys)
-        when Hash
+        when Hash, ActionController::Parameters
           route_name = options.delete :use_route
-          _routes.url_for(options.symbolize_keys.reverse_merge!(url_options),
-                         route_name)
-        when ActionController::Parameters
-          unless options.permitted?
-            raise ArgumentError.new(ActionDispatch::Routing::INSECURE_URL_PARAMETERS_MESSAGE)
-          end
-          route_name = options.delete :use_route
-          _routes.url_for(options.to_h.symbolize_keys.
-                          reverse_merge!(url_options), route_name)
+          merged_url_options = options.to_h.symbolize_keys.reverse_merge!(url_options)
+          _routes.url_for(merged_url_options, route_name)
         when String
           options
         when Symbol
@@ -192,22 +191,28 @@ module ActionDispatch
         end
       end
 
+      def route_for(name, *args) # :nodoc:
+        public_send(:"#{name}_url", *args)
+      end
+
       protected
 
-      def optimize_routes_generation?
-        _routes.optimize_routes_generation? && default_url_options.empty?
-      end
+        def optimize_routes_generation?
+          _routes.optimize_routes_generation? && default_url_options.empty?
+        end
 
-      def _with_routes(routes)
-        old_routes, @_routes = @_routes, routes
-        yield
-      ensure
-        @_routes = old_routes
-      end
+      private
 
-      def _routes_context
-        self
-      end
+        def _with_routes(routes) # :doc:
+          old_routes, @_routes = @_routes, routes
+          yield
+        ensure
+          @_routes = old_routes
+        end
+
+        def _routes_context # :doc:
+          self
+        end
     end
   end
 end
diff --git a/actionpack/lib/action_dispatch/system_test_case.rb b/actionpack/lib/action_dispatch/system_test_case.rb
new file mode 100644
index 0000000000..393141535b
--- /dev/null
+++ b/actionpack/lib/action_dispatch/system_test_case.rb
@@ -0,0 +1,146 @@
+# frozen_string_literal: true
+
+gem "capybara", "~> 2.15"
+
+require "capybara/dsl"
+require "capybara/minitest"
+require "action_controller"
+require "action_dispatch/system_testing/driver"
+require "action_dispatch/system_testing/server"
+require "action_dispatch/system_testing/test_helpers/screenshot_helper"
+require "action_dispatch/system_testing/test_helpers/setup_and_teardown"
+require "action_dispatch/system_testing/test_helpers/undef_methods"
+
+module ActionDispatch
+  # = System Testing
+  #
+  # System tests let you test applications in the browser. Because system
+  # tests use a real browser experience, you can test all of your JavaScript
+  # easily from your test suite.
+  #
+  # To create a system test in your application, extend your test class
+  # from <tt>ApplicationSystemTestCase</tt>. System tests use Capybara as a
+  # base and allow you to configure the settings through your
+  # <tt>application_system_test_case.rb</tt> file that is generated with a new
+  # application or scaffold.
+  #
+  # Here is an example system test:
+  #
+  #   require 'application_system_test_case'
+  #
+  #   class Users::CreateTest < ApplicationSystemTestCase
+  #     test "adding a new user" do
+  #       visit users_path
+  #       click_on 'New User'
+  #
+  #       fill_in 'Name', with: 'Arya'
+  #       click_on 'Create User'
+  #
+  #       assert_text 'Arya'
+  #     end
+  #   end
+  #
+  # When generating an application or scaffold, an +application_system_test_case.rb+
+  # file will also be generated containing the base class for system testing.
+  # This is where you can change the driver, add Capybara settings, and other
+  # configuration for your system tests.
+  #
+  #   require "test_helper"
+  #
+  #   class ApplicationSystemTestCase < ActionDispatch::SystemTestCase
+  #     driven_by :selenium, using: :chrome, screen_size: [1400, 1400]
+  #   end
+  #
+  # By default, <tt>ActionDispatch::SystemTestCase</tt> is driven by the
+  # Selenium driver, with the Chrome browser, and a browser size of 1400x1400.
+  #
+  # Changing the driver configuration options is easy. Let's say you want to use
+  # the Firefox browser instead of Chrome. In your +application_system_test_case.rb+
+  # file add the following:
+  #
+  #   require "test_helper"
+  #
+  #   class ApplicationSystemTestCase < ActionDispatch::SystemTestCase
+  #     driven_by :selenium, using: :firefox
+  #   end
+  #
+  # +driven_by+ has a required argument for the driver name. The keyword
+  # arguments are +:using+ for the browser and +:screen_size+ to change the
+  # size of the browser screen. These two options are not applicable for
+  # headless drivers and will be silently ignored if passed.
+  #
+  # Headless browsers such as headless Chrome and headless Firefox are also supported.
+  # You can use these browsers by setting the +:using+ argument to +:headless_chrome+ or +:headless_firefox+.
+  #
+  # To use a headless driver, like Poltergeist, update your Gemfile to use
+  # Poltergeist instead of Selenium and then declare the driver name in the
+  # +application_system_test_case.rb+ file. In this case, you would leave out
+  # the +:using+ option because the driver is headless, but you can still use
+  # +:screen_size+ to change the size of the browser screen, also you can use
+  # +:options+ to pass options supported by the driver. Please refer to your
+  # driver documentation to learn about supported options.
+  #
+  #   require "test_helper"
+  #   require "capybara/poltergeist"
+  #
+  #   class ApplicationSystemTestCase < ActionDispatch::SystemTestCase
+  #     driven_by :poltergeist, screen_size: [1400, 1400], options:
+  #       { js_errors: true }
+  #   end
+  #
+  # Because <tt>ActionDispatch::SystemTestCase</tt> is a shim between Capybara
+  # and Rails, any driver that is supported by Capybara is supported by system
+  # tests as long as you include the required gems and files.
+  class SystemTestCase < IntegrationTest
+    include Capybara::DSL
+    include Capybara::Minitest::Assertions
+    include SystemTesting::TestHelpers::SetupAndTeardown
+    include SystemTesting::TestHelpers::ScreenshotHelper
+    include SystemTesting::TestHelpers::UndefMethods
+
+    def initialize(*) # :nodoc:
+      super
+      self.class.driver.use
+    end
+
+    def self.start_application # :nodoc:
+      Capybara.app = Rack::Builder.new do
+        map "/" do
+          run Rails.application
+        end
+      end
+
+      SystemTesting::Server.new.run
+    end
+
+    class_attribute :driver, instance_accessor: false
+
+    # System Test configuration options
+    #
+    # The default settings are Selenium, using Chrome, with a screen size
+    # of 1400x1400.
+    #
+    # Examples:
+    #
+    #   driven_by :poltergeist
+    #
+    #   driven_by :selenium, screen_size: [800, 800]
+    #
+    #   driven_by :selenium, using: :chrome
+    #
+    #   driven_by :selenium, using: :headless_chrome
+    #
+    #   driven_by :selenium, using: :firefox
+    #
+    #   driven_by :selenium, using: :headless_firefox
+    def self.driven_by(driver, using: :chrome, screen_size: [1400, 1400], options: {})
+      self.driver = SystemTesting::Driver.new(driver, using: using, screen_size: screen_size, options: options)
+    end
+
+    driven_by :selenium
+
+    ActiveSupport.run_load_hooks(:action_dispatch_system_test_case, self)
+  end
+
+  SystemTestCase.start_application
+end
diff --git a/actionpack/lib/action_dispatch/system_testing/driver.rb b/actionpack/lib/action_dispatch/system_testing/driver.rb
new file mode 100644
index 0000000000..280989a146
--- /dev/null
+++ b/actionpack/lib/action_dispatch/system_testing/driver.rb
@@ -0,0 +1,82 @@
+# frozen_string_literal: true
+
+module ActionDispatch
+  module SystemTesting
+    class Driver # :nodoc:
+      def initialize(name, **options)
+        @name = name
+        @browser = options[:using]
+        @screen_size = options[:screen_size]
+        @options = options[:options]
+      end
+
+      def use
+        register if registerable?
+
+        setup
+      end
+
+      private
+        def registerable?
+          [:selenium, :poltergeist, :webkit].include?(@name)
+        end
+
+        def register
+          Capybara.register_driver @name do |app|
+            case @name
+            when :selenium then register_selenium(app)
+            when :poltergeist then register_poltergeist(app)
+            when :webkit then register_webkit(app)
+            end
+          end
+        end
+
+        def browser_options
+          if @browser == :headless_chrome
+            browser_options = Selenium::WebDriver::Chrome::Options.new
+            browser_options.args << "--headless"
+            browser_options.args << "--disable-gpu"
+
+            @options.merge(options: browser_options)
+          elsif @browser == :headless_firefox
+            browser_options = Selenium::WebDriver::Firefox::Options.new
+            browser_options.args << "-headless"
+
+            @options.merge(options: browser_options)
+          else
+            @options
+          end
+        end
+
+        def browser
+          if @browser == :headless_chrome
+            :chrome
+          elsif @browser == :headless_firefox
+            :firefox
+          else
+            @browser
+          end
+        end
+
+        def register_selenium(app)
+          Capybara::Selenium::Driver.new(app, { browser: browser }.merge(browser_options)).tap do |driver|
+            driver.browser.manage.window.size = Selenium::WebDriver::Dimension.new(*@screen_size)
+          end
+        end
+
+        def register_poltergeist(app)
+          Capybara::Poltergeist::Driver.new(app, @options.merge(window_size: @screen_size))
+        end
+
+        def register_webkit(app)
+          Capybara::Webkit::Driver.new(app, Capybara::Webkit::Configuration.to_hash.merge(@options)).tap do |driver|
+            driver.resize_window_to(driver.current_window_handle, *@screen_size)
+          end
+        end
+
+        def setup
+          Capybara.current_driver = @name
+        end
+    end
+  end
+end
diff --git a/actionpack/lib/action_dispatch/system_testing/server.rb b/actionpack/lib/action_dispatch/system_testing/server.rb
new file mode 100644
index 0000000000..4fc1f33767
--- /dev/null
+++ b/actionpack/lib/action_dispatch/system_testing/server.rb
@@ -0,0 +1,31 @@
+# frozen_string_literal: true
+
+module ActionDispatch
+  module SystemTesting
+    class Server # :nodoc:
+      class << self
+        attr_accessor :silence_puma
+      end
+
+      self.silence_puma = false
+
+      def run
+        setup
+      end
+
+      private
+        def setup
+          set_server
+          set_port
+        end
+
+        def set_server
+          Capybara.server = :puma, { Silent: self.class.silence_puma } if Capybara.server == Capybara.servers[:default]
+        end
+
+        def set_port
+          Capybara.always_include_port = true
+        end
+    end
+  end
+end
diff --git a/actionpack/lib/action_dispatch/system_testing/test_helpers/screenshot_helper.rb b/actionpack/lib/action_dispatch/system_testing/test_helpers/screenshot_helper.rb
new file mode 100644
index 0000000000..df0c5d3f0e
--- /dev/null
+++ b/actionpack/lib/action_dispatch/system_testing/test_helpers/screenshot_helper.rb
@@ -0,0 +1,96 @@
+# frozen_string_literal: true
+
+module ActionDispatch
+  module SystemTesting
+    module TestHelpers
+      # Screenshot helper for system testing.
+      module ScreenshotHelper
+        # Takes a screenshot of the current page in the browser.
+        #
+        # +take_screenshot+ can be used at any point in your system tests to take
+        # a screenshot of the current state. This can be useful for debugging or
+        # automating visual testing.
+        #
+        # The screenshot will be displayed in your console, if supported.
+        #
+        # You can set the +RAILS_SYSTEM_TESTING_SCREENSHOT+ environment variable to
+        # control the output. Possible values are:
+        # * [+simple+ (default)]    Only displays the screenshot path.
+        #                           This is the default value.
+        # * [+inline+]              Display the screenshot in the terminal using the
+        #                           iTerm image protocol (https://iterm2.com/documentation-images.html).
+        # * [+artifact+]            Display the screenshot in the terminal, using the terminal
+        #                           artifact format (https://buildkite.github.io/terminal/inline-images/).
+        def take_screenshot
+          save_image
+          puts display_image
+        end
+
+        # Takes a screenshot of the current page in the browser if the test
+        # failed.
+        #
+        # +take_failed_screenshot+ is included in <tt>application_system_test_case.rb</tt>
+        # that is generated with the application. To take screenshots when a test
+        # fails add +take_failed_screenshot+ to the teardown block before clearing
+        # sessions.
+        def take_failed_screenshot
+          take_screenshot if failed? && supports_screenshot?
+        end
+
+        private
+          def image_name
+            failed? ? "failures_#{method_name}" : method_name
+          end
+
+          def image_path
+            @image_path ||= absolute_image_path.relative_path_from(Pathname.pwd).to_s
+          end
+
+          def absolute_image_path
+            Rails.root.join("tmp/screenshots/#{image_name}.png")
+          end
+
+          def save_image
+            page.save_screenshot(absolute_image_path)
+          end
+
+          def output_type
+            # Environment variables have priority
+            output_type = ENV["RAILS_SYSTEM_TESTING_SCREENSHOT"] || ENV["CAPYBARA_INLINE_SCREENSHOT"]
+
+            # Default to outputting a path to the screenshot
+            output_type ||= "simple"
+
+            output_type
+          end
+
+          def display_image
+            message = "[Screenshot]: #{image_path}\n".dup
+
+            case output_type
+            when "artifact"
+              message << "\e]1338;url=artifact://#{absolute_image_path}\a\n"
+            when "inline"
+              name = inline_base64(File.basename(absolute_image_path))
+              image = inline_base64(File.read(absolute_image_path))
+              message << "\e]1337;File=name=#{name};height=400px;inline=1:#{image}\a\n"
+            end
+
+            message
+          end
+
+          def inline_base64(path)
+            Base64.encode64(path).gsub("\n", "")
+          end
+
+          def failed?
+            !passed? && !skipped?
+          end
+
+          def supports_screenshot?
+            Capybara.current_driver != :rack_test
+          end
+      end
+    end
+  end
+end
diff --git a/actionpack/lib/action_dispatch/system_testing/test_helpers/setup_and_teardown.rb b/actionpack/lib/action_dispatch/system_testing/test_helpers/setup_and_teardown.rb
new file mode 100644
index 0000000000..ffa85f4e14
--- /dev/null
+++ b/actionpack/lib/action_dispatch/system_testing/test_helpers/setup_and_teardown.rb
@@ -0,0 +1,27 @@
+# frozen_string_literal: true
+
+module ActionDispatch
+  module SystemTesting
+    module TestHelpers
+      module SetupAndTeardown # :nodoc:
+        DEFAULT_HOST = "http://127.0.0.1"
+
+        def host!(host)
+          super
+          Capybara.app_host = host
+        end
+
+        def before_setup
+          host! DEFAULT_HOST
+          super
+        end
+
+        def after_teardown
+          take_failed_screenshot
+          Capybara.reset_sessions!
+          super
+        end
+      end
+    end
+  end
+end
diff --git a/actionpack/lib/action_dispatch/system_testing/test_helpers/undef_methods.rb b/actionpack/lib/action_dispatch/system_testing/test_helpers/undef_methods.rb
new file mode 100644
index 0000000000..d64be3b3d9
--- /dev/null
+++ b/actionpack/lib/action_dispatch/system_testing/test_helpers/undef_methods.rb
@@ -0,0 +1,26 @@
+# frozen_string_literal: true
+
+module ActionDispatch
+  module SystemTesting
+    module TestHelpers
+      module UndefMethods # :nodoc:
+        extend ActiveSupport::Concern
+        included do
+          METHODS = %i(get post put patch delete).freeze
+
+          METHODS.each do |verb|
+            undef_method verb
+          end
+
+          def method_missing(method, *args, &block)
+            if METHODS.include?(method)
+              raise NoMethodError, "System tests cannot make direct requests via ##{method}; use #visit and #click_on instead. See http://www.rubydoc.info/github/teamcapybara/capybara/master#The_DSL for more information."
+            else
+              super
+            end
+          end
+        end
+      end
+    end
+  end
+end
diff --git a/actionpack/lib/action_dispatch/testing/assertion_response.rb b/actionpack/lib/action_dispatch/testing/assertion_response.rb
index 404b96bbcd..dc019db6ac 100644
--- a/actionpack/lib/action_dispatch/testing/assertion_response.rb
+++ b/actionpack/lib/action_dispatch/testing/assertion_response.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActionDispatch
   # This is a class that abstracts away an asserted response. It purposely
   # does not inherit from Response because it doesn't need it. That means it
@@ -34,12 +36,12 @@ module ActionDispatch
 
     private
 
-    def code_from_name(name)
-      GENERIC_RESPONSE_CODES[name] || Rack::Utils::SYMBOL_TO_STATUS_CODE[name]
-    end
+      def code_from_name(name)
+        GENERIC_RESPONSE_CODES[name] || Rack::Utils::SYMBOL_TO_STATUS_CODE[name]
+      end
 
-    def name_from_code(code)
-      GENERIC_RESPONSE_CODES.invert[code] || Rack::Utils::HTTP_STATUS_CODES[code]
-    end
+      def name_from_code(code)
+        GENERIC_RESPONSE_CODES.invert[code] || Rack::Utils::HTTP_STATUS_CODES[code]
+      end
   end
 end
diff --git a/actionpack/lib/action_dispatch/testing/assertions.rb b/actionpack/lib/action_dispatch/testing/assertions.rb
index fae266273e..08c2969685 100644
--- a/actionpack/lib/action_dispatch/testing/assertions.rb
+++ b/actionpack/lib/action_dispatch/testing/assertions.rb
@@ -1,9 +1,11 @@
-require 'rails-dom-testing'
+# frozen_string_literal: true
+
+require "rails-dom-testing"
 
 module ActionDispatch
   module Assertions
-    autoload :ResponseAssertions, 'action_dispatch/testing/assertions/response'
-    autoload :RoutingAssertions, 'action_dispatch/testing/assertions/routing'
+    autoload :ResponseAssertions, "action_dispatch/testing/assertions/response"
+    autoload :RoutingAssertions, "action_dispatch/testing/assertions/routing"
 
     extend ActiveSupport::Concern
 
@@ -12,7 +14,7 @@ module ActionDispatch
     include Rails::Dom::Testing::Assertions
 
     def html_document
-      @html_document ||= if @response.content_type.to_s =~ /xml\z/
+      @html_document ||= if @response.content_type.to_s.end_with?("xml")
         Nokogiri::XML::Document.parse(@response.body)
       else
         Nokogiri::HTML::Document.parse(@response.body)
diff --git a/actionpack/lib/action_dispatch/testing/assertions/response.rb b/actionpack/lib/action_dispatch/testing/assertions/response.rb
index cd55b7d975..98b1965d22 100644
--- a/actionpack/lib/action_dispatch/testing/assertions/response.rb
+++ b/actionpack/lib/action_dispatch/testing/assertions/response.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActionDispatch
   module Assertions
     # A small suite of assertions that test responses from \Rails applications.
@@ -45,12 +47,12 @@ module ActionDispatch
       #   # Asserts that the redirection was to the named route login_url
       #   assert_redirected_to login_url
       #
-      #   # Asserts that the redirection was to the url for @customer
+      #   # Asserts that the redirection was to the URL for @customer
       #   assert_redirected_to @customer
       #
       #   # Asserts that the redirection matches the regular expression
       #   assert_redirected_to %r(\Ahttp://example.org)
-      def assert_redirected_to(options = {}, message=nil)
+      def assert_redirected_to(options = {}, message = nil)
         assert_response(:redirect, message)
         return true if options === @response.location
 
@@ -79,11 +81,16 @@ module ActionDispatch
         def generate_response_message(expected, actual = @response.response_code)
           "Expected response to be a <#{code_with_name(expected)}>,"\
           " but was a <#{code_with_name(actual)}>"
-          .concat location_if_redirected
+            .dup.concat(location_if_redirected).concat(response_body_if_short)
+        end
+
+        def response_body_if_short
+          return "" if @response.body.size > 500
+          "\nResponse body: #{@response.body}"
         end
 
         def location_if_redirected
-          return '' unless @response.redirection? && @response.location.present?
+          return "" unless @response.redirection? && @response.location.present?
           location = normalize_argument_to_redirection(@response.location)
           " redirect to <#{location}>"
         end
diff --git a/actionpack/lib/action_dispatch/testing/assertions/routing.rb b/actionpack/lib/action_dispatch/testing/assertions/routing.rb
index 44ad2c10d8..5390581139 100644
--- a/actionpack/lib/action_dispatch/testing/assertions/routing.rb
+++ b/actionpack/lib/action_dispatch/testing/assertions/routing.rb
@@ -1,7 +1,9 @@
-require 'uri'
-require 'active_support/core_ext/hash/indifferent_access'
-require 'active_support/core_ext/string/access'
-require 'action_controller/metal/exceptions'
+# frozen_string_literal: true
+
+require "uri"
+require "active_support/core_ext/hash/indifferent_access"
+require "active_support/core_ext/string/access"
+require "action_controller/metal/exceptions"
 
 module ActionDispatch
   module Assertions
@@ -18,8 +20,8 @@ module ActionDispatch
       #   assert_recognizes({controller: 'items', action: 'create'}, {path: 'items', method: :post})
       #
       # You can also pass in +extras+ with a hash containing URL parameters that would normally be in the query string. This can be used
-      # to assert that values in the query string will end up in the params hash correctly. To test query strings you must use the
-      # extras argument, appending the query string on the path directly will not work. For example:
+      # to assert that values in the query string will end up in the params hash correctly. To test query strings you must use the extras
+      # argument because appending the query string on the path directly will not work. For example:
       #
       #   # Asserts that a path of '/items/list/1?view=print' returns the correct options
       #   assert_recognizes({controller: 'items', action: 'list', id: '1', view: 'print'}, 'items/list/1', { view: "print" })
@@ -37,7 +39,7 @@ module ActionDispatch
       #
       #   # Test a custom route
       #   assert_recognizes({controller: 'items', action: 'show', id: '1'}, 'view/item1')
-      def assert_recognizes(expected_options, path, extras={}, msg=nil)
+      def assert_recognizes(expected_options, path, extras = {}, msg = nil)
         if path.is_a?(Hash) && path[:method].to_s == "all"
           [:get, :post, :put, :delete].each do |method|
             assert_recognizes(expected_options, path.merge(method: method), extras, msg)
@@ -75,14 +77,14 @@ module ActionDispatch
       #
       #   # Asserts that the generated route gives us our custom route
       #   assert_generates "changesets/12", { controller: 'scm', action: 'show_diff', revision: "12" }
-      def assert_generates(expected_path, options, defaults={}, extras={}, message=nil)
+      def assert_generates(expected_path, options, defaults = {}, extras = {}, message = nil)
         if expected_path =~ %r{://}
           fail_on(URI::InvalidURIError, message) do
             uri = URI.parse(expected_path)
             expected_path = uri.path.to_s.empty? ? "/" : uri.path
           end
         else
-          expected_path = "/#{expected_path}" unless expected_path.first == '/'
+          expected_path = "/#{expected_path}" unless expected_path.first == "/"
         end
         # Load routes.rb if it hasn't been loaded.
 
@@ -119,7 +121,7 @@ module ActionDispatch
       #
       #  # Tests a route with an HTTP method
       #  assert_routing({ method: 'put', path: '/product/321' }, { controller: "product", action: "update", id: "321" })
-      def assert_routing(path, options, defaults={}, extras={}, message=nil)
+      def assert_routing(path, options, defaults = {}, extras = {}, message = nil)
         assert_recognizes(options, path, extras, message)
 
         controller, default_controller = options[:controller], defaults[:controller]
@@ -127,13 +129,12 @@ module ActionDispatch
           options[:controller] = "/#{controller}"
         end
 
-        generate_options = options.dup.delete_if{ |k, _| defaults.key?(k) }
+        generate_options = options.dup.delete_if { |k, _| defaults.key?(k) }
         assert_generates(path.is_a?(Hash) ? path[:path] : path, generate_options, defaults, extras, message)
       end
 
       # A helper to make it easier to test different route configurations.
-      # This method temporarily replaces @routes
-      # with a new RouteSet instance.
+      # This method temporarily replaces @routes with a new RouteSet instance.
       #
       # The new instance is yielded to the passed block. Typically the block
       # will create some routes using <tt>set.draw { match ... }</tt>:
@@ -152,8 +153,11 @@ module ActionDispatch
           _routes = @routes
 
           @controller.singleton_class.include(_routes.url_helpers)
-          @controller.view_context_class = Class.new(@controller.view_context_class) do
-            include _routes.url_helpers
+
+          if @controller.respond_to? :view_context_class
+            @controller.view_context_class = Class.new(@controller.view_context_class) do
+              include _routes.url_helpers
+            end
           end
         end
         yield @routes
@@ -183,8 +187,7 @@ module ActionDispatch
             method = :get
           end
 
-          # Assume given controller
-          request = ActionController::TestRequest.create
+          request = ActionController::TestRequest.create @controller.class
 
           if path =~ %r{://}
             fail_on(URI::InvalidURIError, msg) do
@@ -202,7 +205,7 @@ module ActionDispatch
           request.request_method = method if method
 
           params = fail_on(ActionController::RoutingError, msg) do
-            @routes.recognize_path(path, { :method => method, :extras => extras })
+            @routes.recognize_path(path, method: method, extras: extras)
           end
           request.path_parameters = params.with_indifferent_access
 
diff --git a/actionpack/lib/action_dispatch/testing/integration.rb b/actionpack/lib/action_dispatch/testing/integration.rb
index 8777666f9f..7171b6942c 100644
--- a/actionpack/lib/action_dispatch/testing/integration.rb
+++ b/actionpack/lib/action_dispatch/testing/integration.rb
@@ -1,106 +1,52 @@
-require 'stringio'
-require 'uri'
-require 'active_support/core_ext/kernel/singleton_class'
-require 'active_support/core_ext/object/try'
-require 'active_support/core_ext/string/strip'
-require 'rack/test'
-require 'minitest'
+# frozen_string_literal: true
+
+require "stringio"
+require "uri"
+require "active_support/core_ext/kernel/singleton_class"
+require "active_support/core_ext/object/try"
+require "rack/test"
+require "minitest"
+
+require "action_dispatch/testing/request_encoder"
 
 module ActionDispatch
   module Integration #:nodoc:
     module RequestHelpers
-      # Performs a GET request with the given parameters.
-      #
-      # - +path+: The URI (as a String) on which you want to perform a GET
-      #   request.
-      # - +params+: The HTTP parameters that you want to pass. This may
-      #   be +nil+,
-      #   a Hash, or a String that is appropriately encoded
-      #   (<tt>application/x-www-form-urlencoded</tt> or
-      #   <tt>multipart/form-data</tt>).
-      # - +headers+: Additional headers to pass, as a Hash. The headers will be
-      #   merged into the Rack env hash.
-      # - +env+: Additional env to pass, as a Hash. The headers will be
-      #   merged into the Rack env hash.
-      #
-      # This method returns a Response object, which one can use to
-      # inspect the details of the response. Furthermore, if this method was
-      # called from an ActionDispatch::IntegrationTest object, then that
-      # object's <tt>@response</tt> instance variable will point to the same
-      # response object.
-      #
-      # You can also perform POST, PATCH, PUT, DELETE, and HEAD requests with
-      # +#post+, +#patch+, +#put+, +#delete+, and +#head+.
-      #
-      # Example:
-      #
-      #   get '/feed', params: { since: 201501011400 }
-      #   post '/profile', headers: { "X-Test-Header" => "testvalue" }
-      def get(path, *args)
-        process_with_kwargs(:get, path, *args)
+      # Performs a GET request with the given parameters. See ActionDispatch::Integration::Session#process
+      # for more details.
+      def get(path, **args)
+        process(:get, path, **args)
       end
 
-      # Performs a POST request with the given parameters. See +#get+ for more
-      # details.
-      def post(path, *args)
-        process_with_kwargs(:post, path, *args)
+      # Performs a POST request with the given parameters. See ActionDispatch::Integration::Session#process
+      # for more details.
+      def post(path, **args)
+        process(:post, path, **args)
       end
 
-      # Performs a PATCH request with the given parameters. See +#get+ for more
-      # details.
-      def patch(path, *args)
-        process_with_kwargs(:patch, path, *args)
+      # Performs a PATCH request with the given parameters. See ActionDispatch::Integration::Session#process
+      # for more details.
+      def patch(path, **args)
+        process(:patch, path, **args)
       end
 
-      # Performs a PUT request with the given parameters. See +#get+ for more
-      # details.
-      def put(path, *args)
-        process_with_kwargs(:put, path, *args)
+      # Performs a PUT request with the given parameters. See ActionDispatch::Integration::Session#process
+      # for more details.
+      def put(path, **args)
+        process(:put, path, **args)
       end
 
-      # Performs a DELETE request with the given parameters. See +#get+ for
-      # more details.
-      def delete(path, *args)
-        process_with_kwargs(:delete, path, *args)
+      # Performs a DELETE request with the given parameters. See ActionDispatch::Integration::Session#process
+      # for more details.
+      def delete(path, **args)
+        process(:delete, path, **args)
       end
 
-      # Performs a HEAD request with the given parameters. See +#get+ for more
-      # details.
+      # Performs a HEAD request with the given parameters. See ActionDispatch::Integration::Session#process
+      # for more details.
       def head(path, *args)
-        process_with_kwargs(:head, path, *args)
-      end
-
-      # Performs an XMLHttpRequest request with the given parameters, mirroring
-      # an AJAX request made from JavaScript.
-      #
-      # The request_method is +:get+, +:post+, +:patch+, +:put+, +:delete+ or
-      # +:head+; the parameters are +nil+, a hash, or a url-encoded or multipart
-      # string; the headers are a hash.
-      #
-      # Example:
-      #
-      #   xhr :get, '/feed', params: { since: 201501011400 }
-      def xml_http_request(request_method, path, *args)
-        if kwarg_request?(args)
-          params, headers, env = args.first.values_at(:params, :headers, :env)
-        else
-          params = args[0]
-          headers = args[1]
-          env = {}
-
-          if params.present? || headers.present?
-            non_kwarg_request_warning
-          end
-        end
-
-        ActiveSupport::Deprecation.warn(<<-MSG.strip_heredoc)
-          xhr and xml_http_request methods are deprecated in favor of
-          `get "/posts", xhr: true` and `post "/posts/1", xhr: true`.
-        MSG
-
-        process(request_method, path, params: params, headers: headers, xhr: true)
+        process(:head, path, *args)
       end
-      alias xhr :xml_http_request
 
       # Follow a single redirect response. If the last response was not a
       # redirect, an exception will be raised. Otherwise, the redirect is
@@ -110,59 +56,6 @@ module ActionDispatch
         get(response.location)
         status
       end
-
-      # Performs a request using the specified method, following any subsequent
-      # redirect. Note that the redirects are followed until the response is
-      # not a redirect--this means you may run into an infinite loop if your
-      # redirect loops back to itself.
-      #
-      # Example:
-      #
-      #   request_via_redirect :post, '/welcome',
-      #     params: { ref_id: 14 },
-      #     headers: { "X-Test-Header" => "testvalue" }
-      def request_via_redirect(http_method, path, *args)
-        ActiveSupport::Deprecation.warn('`request_via_redirect` is deprecated and will be removed in Rails 5.1. Please use `follow_redirect!` manually after the request call for the same behavior.')
-        process_with_kwargs(http_method, path, *args)
-
-        follow_redirect! while redirect?
-        status
-      end
-
-      # Performs a GET request, following any subsequent redirect.
-      # See +request_via_redirect+ for more information.
-      def get_via_redirect(path, *args)
-        ActiveSupport::Deprecation.warn('`get_via_redirect` is deprecated and will be removed in Rails 5.1. Please use `follow_redirect!` manually after the request call for the same behavior.')
-        request_via_redirect(:get, path, *args)
-      end
-
-      # Performs a POST request, following any subsequent redirect.
-      # See +request_via_redirect+ for more information.
-      def post_via_redirect(path, *args)
-        ActiveSupport::Deprecation.warn('`post_via_redirect` is deprecated and will be removed in Rails 5.1. Please use `follow_redirect!` manually after the request call for the same behavior.')
-        request_via_redirect(:post, path, *args)
-      end
-
-      # Performs a PATCH request, following any subsequent redirect.
-      # See +request_via_redirect+ for more information.
-      def patch_via_redirect(path, *args)
-        ActiveSupport::Deprecation.warn('`patch_via_redirect` is deprecated and will be removed in Rails 5.1. Please use `follow_redirect!` manually after the request call for the same behavior.')
-        request_via_redirect(:patch, path, *args)
-      end
-
-      # Performs a PUT request, following any subsequent redirect.
-      # See +request_via_redirect+ for more information.
-      def put_via_redirect(path, *args)
-        ActiveSupport::Deprecation.warn('`put_via_redirect` is deprecated and will be removed in Rails 5.1. Please use `follow_redirect!` manually after the request call for the same behavior.')
-        request_via_redirect(:put, path, *args)
-      end
-
-      # Performs a DELETE request, following any subsequent redirect.
-      # See +request_via_redirect+ for more information.
-      def delete_via_redirect(path, *args)
-        ActiveSupport::Deprecation.warn('`delete_via_redirect` is deprecated and will be removed in Rails 5.1. Please use `follow_redirect!` manually after the request call for the same behavior.')
-        request_via_redirect(:delete, path, *args)
-      end
     end
 
     # An instance of this class represents a set of requests and responses
@@ -180,11 +73,11 @@ module ActionDispatch
       include TestProcess, RequestHelpers, Assertions
 
       %w( status status_message headers body redirect? ).each do |method|
-        delegate method, :to => :response, :allow_nil => true
+        delegate method, to: :response, allow_nil: true
       end
 
       %w( path ).each do |method|
-        delegate method, :to => :request, :allow_nil => true
+        delegate method, to: :request, allow_nil: true
       end
 
       # The hostname used in the last request.
@@ -235,7 +128,7 @@ module ActionDispatch
             url_options.reverse_merge!(@app.routes.default_url_options)
           end
 
-          url_options.reverse_merge!(:host => host, :protocol => https? ? "https" : "http")
+          url_options.reverse_merge!(host: host, protocol: https? ? "https" : "http")
         end
       end
 
@@ -253,8 +146,8 @@ module ActionDispatch
 
         self.host        = DEFAULT_HOST
         self.remote_addr = "127.0.0.1"
-        self.accept      = "text/xml,application/xml,application/xhtml+xml," +
-                           "text/html;q=0.9,text/plain;q=0.8,image/png," +
+        self.accept      = "text/xml,application/xml,application/xhtml+xml," \
+                           "text/html;q=0.9,text/plain;q=0.8,image/png," \
                            "*/*;q=0.5"
 
         unless defined? @named_routes_configured
@@ -281,169 +174,126 @@ module ActionDispatch
         @https
       end
 
-      # Set the host name to use in the next request.
+      # Performs the actual request.
       #
-      #   session.host! "www.example.com"
-      alias :host! :host=
-
-      private
-        def _mock_session
-          @_mock_session ||= Rack::MockSession.new(@app, host)
-        end
-
-        def process_with_kwargs(http_method, path, *args)
-          if kwarg_request?(args)
-            process(http_method, path, *args)
-          else
-            non_kwarg_request_warning if args.any?
-            process(http_method, path, { params: args[0], headers: args[1] })
-          end
-        end
-
-        REQUEST_KWARGS = %i(params headers env xhr as)
-        def kwarg_request?(args)
-          args[0].respond_to?(:keys) && args[0].keys.any? { |k| REQUEST_KWARGS.include?(k) }
-        end
-
-        def non_kwarg_request_warning
-          ActiveSupport::Deprecation.warn(<<-MSG.strip_heredoc)
-            ActionDispatch::IntegrationTest HTTP request methods will accept only
-            the following keyword arguments in future Rails versions:
-            #{REQUEST_KWARGS.join(', ')}
-
-            Examples:
-
-            get '/profile',
-              params: { id: 1 },
-              headers: { 'X-Extra-Header' => '123' },
-              env: { 'action_dispatch.custom' => 'custom' },
-              xhr: true,
-              as: :json
-          MSG
+      # - +method+: The HTTP method (GET, POST, PATCH, PUT, DELETE, HEAD, OPTIONS)
+      #   as a symbol.
+      # - +path+: The URI (as a String) on which you want to perform the
+      #   request.
+      # - +params+: The HTTP parameters that you want to pass. This may
+      #   be +nil+,
+      #   a Hash, or a String that is appropriately encoded
+      #   (<tt>application/x-www-form-urlencoded</tt> or
+      #   <tt>multipart/form-data</tt>).
+      # - +headers+: Additional headers to pass, as a Hash. The headers will be
+      #   merged into the Rack env hash.
+      # - +env+: Additional env to pass, as a Hash. The headers will be
+      #   merged into the Rack env hash.
+      #
+      # This method is rarely used directly. Use +#get+, +#post+, or other standard
+      # HTTP methods in integration tests. +#process+ is only required when using a
+      # request method that doesn't have a method defined in the integration tests.
+      #
+      # This method returns the response status, after performing the request.
+      # Furthermore, if this method was called from an ActionDispatch::IntegrationTest object,
+      # then that object's <tt>@response</tt> instance variable will point to a Response object
+      # which one can use to inspect the details of the response.
+      #
+      # Example:
+      #   process :get, '/author', params: { since: 201501011400 }
+      def process(method, path, params: nil, headers: nil, env: nil, xhr: false, as: nil)
+        request_encoder = RequestEncoder.encoder(as)
+        headers ||= {}
+
+        if method == :get && as == :json && params
+          headers["X-Http-Method-Override"] = "GET"
+          method = :post
         end
 
-        # Performs the actual request.
-        def process(method, path, params: nil, headers: nil, env: nil, xhr: false, as: nil)
-          request_encoder = RequestEncoder.encoder(as)
-
-          if path =~ %r{://}
-            location = URI.parse(path)
+        if path =~ %r{://}
+          path = build_expanded_path(path) do |location|
             https! URI::HTTPS === location if location.scheme
+
             if url_host = location.host
               default = Rack::Request::DEFAULT_PORTS[location.scheme]
               url_host += ":#{location.port}" if default != location.port
               host! url_host
             end
-            path = request_encoder.append_format_to location.path
-            path = location.query ? "#{path}?#{location.query}" : path
-          else
-            path = request_encoder.append_format_to path
-          end
-
-          hostname, port = host.split(':')
-
-          request_env = {
-            :method => method,
-            :params => request_encoder.encode_params(params),
-
-            "SERVER_NAME"     => hostname,
-            "SERVER_PORT"     => port || (https? ? "443" : "80"),
-            "HTTPS"           => https? ? "on" : "off",
-            "rack.url_scheme" => https? ? "https" : "http",
-
-            "REQUEST_URI"    => path,
-            "HTTP_HOST"      => host,
-            "REMOTE_ADDR"    => remote_addr,
-            "CONTENT_TYPE"   => request_encoder.content_type,
-            "HTTP_ACCEPT"    => accept
-          }
-
-          if xhr
-            headers ||= {}
-            headers['HTTP_X_REQUESTED_WITH'] = 'XMLHttpRequest'
-            headers['HTTP_ACCEPT'] ||= [Mime[:js], Mime[:html], Mime[:xml], 'text/xml', '*/*'].join(', ')
           end
+        end
 
-          # this modifies the passed request_env directly
-          if headers.present?
-            Http::Headers.from_hash(request_env).merge!(headers)
-          end
-          if env.present?
-            Http::Headers.from_hash(request_env).merge!(env)
-          end
+        hostname, port = host.split(":")
 
-          session = Rack::Test::Session.new(_mock_session)
+        request_env = {
+          :method => method,
+          :params => request_encoder.encode_params(params),
 
-          # NOTE: rack-test v0.5 doesn't build a default uri correctly
-          # Make sure requested path is always a full uri
-          session.request(build_full_uri(path, request_env), request_env)
+          "SERVER_NAME"     => hostname,
+          "SERVER_PORT"     => port || (https? ? "443" : "80"),
+          "HTTPS"           => https? ? "on" : "off",
+          "rack.url_scheme" => https? ? "https" : "http",
 
-          @request_count += 1
-          @request  = ActionDispatch::Request.new(session.last_request.env)
-          response = _mock_session.last_response
-          @response = ActionDispatch::TestResponse.from_response(response)
-          @response.request = @request
-          @response.response_parser = RequestEncoder.parser(@response.content_type)
-          @html_document = nil
-          @url_options = nil
+          "REQUEST_URI"    => path,
+          "HTTP_HOST"      => host,
+          "REMOTE_ADDR"    => remote_addr,
+          "CONTENT_TYPE"   => request_encoder.content_type,
+          "HTTP_ACCEPT"    => request_encoder.accept_header || accept
+        }
 
-          @controller = @request.controller_instance
+        wrapped_headers = Http::Headers.from_hash({})
+        wrapped_headers.merge!(headers) if headers
 
-          response.status
+        if xhr
+          wrapped_headers["HTTP_X_REQUESTED_WITH"] = "XMLHttpRequest"
+          wrapped_headers["HTTP_ACCEPT"] ||= [Mime[:js], Mime[:html], Mime[:xml], "text/xml", "*/*"].join(", ")
         end
 
-        def build_full_uri(path, env)
-          "#{env['rack.url_scheme']}://#{env['SERVER_NAME']}:#{env['SERVER_PORT']}#{path}"
+        # This modifies the passed request_env directly.
+        if wrapped_headers.present?
+          Http::Headers.from_hash(request_env).merge!(wrapped_headers)
+        end
+        if env.present?
+          Http::Headers.from_hash(request_env).merge!(env)
         end
 
-        class RequestEncoder # :nodoc:
-          @encoders = {}
-
-          attr_reader :response_parser
-
-          def initialize(mime_name, param_encoder, response_parser, url_encoded_form = false)
-            @mime = Mime[mime_name]
-
-            unless @mime
-              raise ArgumentError, "Can't register a request encoder for " \
-                "unregistered MIME Type: #{mime_name}. See `Mime::Type.register`."
-            end
+        session = Rack::Test::Session.new(_mock_session)
 
-            @url_encoded_form = url_encoded_form
-            @path_format      = ".#{@mime.symbol}" unless @url_encoded_form
-            @response_parser  = response_parser || -> body { body }
-            @param_encoder    = param_encoder   || :"to_#{@mime.symbol}".to_proc
-          end
+        # NOTE: rack-test v0.5 doesn't build a default uri correctly
+        # Make sure requested path is always a full URI.
+        session.request(build_full_uri(path, request_env), request_env)
 
-          def append_format_to(path)
-            path << @path_format unless @url_encoded_form
-            path
-          end
-
-          def content_type
-            @mime.to_s
-          end
+        @request_count += 1
+        @request = ActionDispatch::Request.new(session.last_request.env)
+        response = _mock_session.last_response
+        @response = ActionDispatch::TestResponse.from_response(response)
+        @response.request = @request
+        @html_document = nil
+        @url_options = nil
 
-          def encode_params(params)
-            @param_encoder.call(params)
-          end
+        @controller = @request.controller_instance
 
-          def self.parser(content_type)
-            mime = Mime::Type.lookup(content_type)
-            encoder(mime ? mime.ref : nil).response_parser
-          end
+        response.status
+      end
 
-          def self.encoder(name)
-            @encoders[name] || WWWFormEncoder
-          end
+      # Set the host name to use in the next request.
+      #
+      #   session.host! "www.example.com"
+      alias :host! :host=
 
-          def self.register_encoder(mime_name, param_encoder: nil, response_parser: nil)
-            @encoders[mime_name] = new(mime_name, param_encoder, response_parser)
-          end
+      private
+        def _mock_session
+          @_mock_session ||= Rack::MockSession.new(@app, host)
+        end
 
-          register_encoder :json, response_parser: -> body { JSON.parse(body) }
+        def build_full_uri(path, env)
+          "#{env['rack.url_scheme']}://#{env['SERVER_NAME']}:#{env['SERVER_PORT']}#{path}"
+        end
 
-          WWWFormEncoder = new(:url_encoded_form, -> params { params }, nil, true)
+        def build_expanded_path(path)
+          location = URI.parse(path)
+          yield location if block_given?
+          path = location.path
+          location.query ? "#{path}?#{location.query}" : path
         end
     end
 
@@ -454,9 +304,13 @@ module ActionDispatch
 
       attr_reader :app
 
+      def initialize(*args, &blk)
+        super(*args, &blk)
+        @integration_session = nil
+      end
+
       def before_setup # :nodoc:
         @app = nil
-        @integration_session = nil
         super
       end
 
@@ -472,8 +326,8 @@ module ActionDispatch
 
       def create_session(app)
         klass = APP_SESSIONS[app] ||= Class.new(Integration::Session) {
-          # If the app is a Rails app, make url_helpers available on the session
-          # This makes app.url_for and app.foo_path available in the console
+          # If the app is a Rails app, make url_helpers available on the session.
+          # This makes app.url_for and app.foo_path available in the console.
           if app.respond_to?(:routes)
             include app.routes.url_helpers
             include app.routes.mounted_helpers
@@ -486,11 +340,10 @@ module ActionDispatch
         @integration_session = nil
       end
 
-      %w(get post patch put head delete cookies assigns
-         xml_http_request xhr get_via_redirect post_via_redirect).each do |method|
+      %w(get post patch put head delete cookies assigns follow_redirect!).each do |method|
         define_method(method) do |*args|
           # reset the html_document variable, except for cookies/assigns calls
-          unless method == 'cookies' || method == 'assigns'
+          unless method == "cookies" || method == "assigns"
             @html_document = nil
           end
 
@@ -512,6 +365,7 @@ module ActionDispatch
       # simultaneously.
       def open_session
         dup.tap do |session|
+          session.reset!
           yield session if block_given?
         end
       end
@@ -532,14 +386,15 @@ module ActionDispatch
         integration_session.default_url_options = options
       end
 
-      def respond_to?(method, include_private = false)
-        integration_session.respond_to?(method, include_private) || super
+    private
+      def respond_to_missing?(method, _)
+        integration_session.respond_to?(method) || super
       end
 
       # Delegate unhandled messages to the current session instance.
-      def method_missing(sym, *args, &block)
-        if integration_session.respond_to?(sym)
-          integration_session.__send__(sym, *args, &block).tap do
+      def method_missing(method, *args, &block)
+        if integration_session.respond_to?(method)
+          integration_session.public_send(method, *args, &block).tap do
             copy_session_variables!
           end
         else
@@ -701,42 +556,50 @@ module ActionDispatch
   #       end
   #   end
   #
+  # See the {request helpers documentation}[rdoc-ref:ActionDispatch::Integration::RequestHelpers] for help on how to
+  # use +get+, etc.
+  #
+  # === Changing the request encoding
+  #
   # You can also test your JSON API easily by setting what the request should
   # be encoded as:
   #
-  #   require 'test_helper'
+  #   require "test_helper"
   #
   #   class ApiTest < ActionDispatch::IntegrationTest
-  #     test 'creates articles' do
+  #     test "creates articles" do
   #       assert_difference -> { Article.count } do
-  #         post articles_path, params: { article: { title: 'Ahoy!' } }, as: :json
+  #         post articles_path, params: { article: { title: "Ahoy!" } }, as: :json
   #       end
   #
   #       assert_response :success
-  #       assert_equal({ id: Arcticle.last.id, title: 'Ahoy!' }, response.parsed_body)
+  #       assert_equal({ id: Article.last.id, title: "Ahoy!" }, response.parsed_body)
   #     end
   #   end
   #
-  # The `as` option sets the format to JSON, sets the content type to
-  # 'application/json' and encodes the parameters as JSON.
+  # The +as+ option passes an "application/json" Accept header (thereby setting
+  # the request format to JSON unless overridden), sets the content type to
+  # "application/json" and encodes the parameters as JSON.
   #
-  # Calling `parsed_body` on the response parses the response body as what
-  # the last request was encoded as. If the request wasn't encoded `as` something,
-  # it's the same as calling `body`.
+  # Calling +parsed_body+ on the response parses the response body based on the
+  # last response MIME type.
   #
-  # For any custom MIME Types you've registered, you can even add your own encoders with:
+  # Out of the box, only <tt>:json</tt> is supported. But for any custom MIME
+  # types you've registered, you can add your own encoders with:
   #
   #   ActionDispatch::IntegrationTest.register_encoder :wibble,
   #     param_encoder: -> params { params.to_wibble },
   #     response_parser: -> body { body }
   #
-  # Where `param_encoder` defines how the params should be encoded and
-  # `response_parser` defines how the response body should be parsed through
-  # `parsed_body`.
+  # Where +param_encoder+ defines how the params should be encoded and
+  # +response_parser+ defines how the response body should be parsed through
+  # +parsed_body+.
   #
   # Consult the Rails Testing Guide for more.
 
   class IntegrationTest < ActiveSupport::TestCase
+    include TestProcess::FixtureFile
+
     module UrlOptions
       extend ActiveSupport::Concern
       def url_options
@@ -759,7 +622,11 @@ module ActionDispatch
 
       module ClassMethods
         def app
-          defined?(@@app) ? @@app : ActionDispatch.test_app
+          if defined?(@@app) && @@app
+            @@app
+          else
+            ActionDispatch.test_app
+          end
         end
 
         def app=(app)
@@ -767,7 +634,7 @@ module ActionDispatch
         end
 
         def register_encoder(*args)
-          Integration::Session::RequestEncoder.register_encoder(*args)
+          RequestEncoder.register_encoder(*args)
         end
       end
 
diff --git a/actionpack/lib/action_dispatch/testing/request_encoder.rb b/actionpack/lib/action_dispatch/testing/request_encoder.rb
new file mode 100644
index 0000000000..01246b7a2e
--- /dev/null
+++ b/actionpack/lib/action_dispatch/testing/request_encoder.rb
@@ -0,0 +1,55 @@
+# frozen_string_literal: true
+
+module ActionDispatch
+  class RequestEncoder # :nodoc:
+    class IdentityEncoder
+      def content_type; end
+      def accept_header; end
+      def encode_params(params); params; end
+      def response_parser; -> body { body }; end
+    end
+
+    @encoders = { identity: IdentityEncoder.new }
+
+    attr_reader :response_parser
+
+    def initialize(mime_name, param_encoder, response_parser)
+      @mime = Mime[mime_name]
+
+      unless @mime
+        raise ArgumentError, "Can't register a request encoder for " \
+          "unregistered MIME Type: #{mime_name}. See `Mime::Type.register`."
+      end
+
+      @response_parser = response_parser || -> body { body }
+      @param_encoder   = param_encoder   || :"to_#{@mime.symbol}".to_proc
+    end
+
+    def content_type
+      @mime.to_s
+    end
+
+    def accept_header
+      @mime.to_s
+    end
+
+    def encode_params(params)
+      @param_encoder.call(params)
+    end
+
+    def self.parser(content_type)
+      mime = Mime::Type.lookup(content_type)
+      encoder(mime ? mime.ref : nil).response_parser
+    end
+
+    def self.encoder(name)
+      @encoders[name] || @encoders[:identity]
+    end
+
+    def self.register_encoder(mime_name, param_encoder: nil, response_parser: nil)
+      @encoders[mime_name] = new(mime_name, param_encoder, response_parser)
+    end
+
+    register_encoder :json, response_parser: -> body { JSON.parse(body) }
+  end
+end
diff --git a/actionpack/lib/action_dispatch/testing/test_process.rb b/actionpack/lib/action_dispatch/testing/test_process.rb
index 1ecd7d14a7..8ac50c730d 100644
--- a/actionpack/lib/action_dispatch/testing/test_process.rb
+++ b/actionpack/lib/action_dispatch/testing/test_process.rb
@@ -1,8 +1,30 @@
-require 'action_dispatch/middleware/cookies'
-require 'action_dispatch/middleware/flash'
+# frozen_string_literal: true
+
+require "action_dispatch/middleware/cookies"
+require "action_dispatch/middleware/flash"
 
 module ActionDispatch
   module TestProcess
+    module FixtureFile
+      # Shortcut for <tt>Rack::Test::UploadedFile.new(File.join(ActionDispatch::IntegrationTest.fixture_path, path), type)</tt>:
+      #
+      #   post :change_avatar, avatar: fixture_file_upload('files/spongebob.png', 'image/png')
+      #
+      # To upload binary files on Windows, pass <tt>:binary</tt> as the last parameter.
+      # This will not affect other platforms:
+      #
+      #   post :change_avatar, avatar: fixture_file_upload('files/spongebob.png', 'image/png', :binary)
+      def fixture_file_upload(path, mime_type = nil, binary = false)
+        if self.class.respond_to?(:fixture_path) && self.class.fixture_path &&
+            !File.exist?(path)
+          path = File.join(self.class.fixture_path, path)
+        end
+        Rack::Test::UploadedFile.new(path, mime_type, binary)
+      end
+    end
+
+    include FixtureFile
+
     def assigns(key = nil)
       raise NoMethodError,
         "assigns has been extracted to a gem. To continue using it,
@@ -24,20 +46,5 @@ module ActionDispatch
     def redirect_to_url
       @response.redirect_url
     end
-
-    # Shortcut for <tt>Rack::Test::UploadedFile.new(File.join(ActionDispatch::IntegrationTest.fixture_path, path), type)</tt>:
-    #
-    #   post :change_avatar, avatar: fixture_file_upload('files/spongebob.png', 'image/png')
-    #
-    # To upload binary files on Windows, pass <tt>:binary</tt> as the last parameter.
-    # This will not affect other platforms:
-    #
-    #   post :change_avatar, avatar: fixture_file_upload('files/spongebob.png', 'image/png', :binary)
-    def fixture_file_upload(path, mime_type = nil, binary = false)
-      if self.class.respond_to?(:fixture_path) && self.class.fixture_path
-        path = File.join(self.class.fixture_path, path)
-      end
-      Rack::Test::UploadedFile.new(path, mime_type, binary)
-    end
   end
 end
diff --git a/actionpack/lib/action_dispatch/testing/test_request.rb b/actionpack/lib/action_dispatch/testing/test_request.rb
index 46523a8600..6c5b7af50e 100644
--- a/actionpack/lib/action_dispatch/testing/test_request.rb
+++ b/actionpack/lib/action_dispatch/testing/test_request.rb
@@ -1,15 +1,17 @@
-require 'active_support/core_ext/hash/indifferent_access'
-require 'rack/utils'
+# frozen_string_literal: true
+
+require "active_support/core_ext/hash/indifferent_access"
+require "rack/utils"
 
 module ActionDispatch
   class TestRequest < Request
-    DEFAULT_ENV = Rack::MockRequest.env_for('/',
-      'HTTP_HOST'                => 'test.host',
-      'REMOTE_ADDR'              => '0.0.0.0',
-      'HTTP_USER_AGENT'          => 'Rails Testing',
+    DEFAULT_ENV = Rack::MockRequest.env_for("/",
+      "HTTP_HOST"                => "test.host",
+      "REMOTE_ADDR"              => "0.0.0.0",
+      "HTTP_USER_AGENT"          => "Rails Testing",
     )
 
-    # Create a new test request with default `env` values
+    # Create a new test request with default +env+ values.
     def self.create(env = {})
       env = Rails.application.env_config.merge(env) if defined?(Rails.application) && Rails.application
       env["rack.request.cookie_hash"] ||= {}.with_indifferent_access
@@ -22,23 +24,23 @@ module ActionDispatch
     private_class_method :default_env
 
     def request_method=(method)
-      set_header('REQUEST_METHOD', method.to_s.upcase)
+      super(method.to_s.upcase)
     end
 
     def host=(host)
-      set_header('HTTP_HOST', host)
+      set_header("HTTP_HOST", host)
     end
 
     def port=(number)
-      set_header('SERVER_PORT', number.to_i)
+      set_header("SERVER_PORT", number.to_i)
     end
 
     def request_uri=(uri)
-      set_header('REQUEST_URI', uri)
+      set_header("REQUEST_URI", uri)
     end
 
     def path=(path)
-      set_header('PATH_INFO', path)
+      set_header("PATH_INFO", path)
     end
 
     def action=(action_name)
@@ -46,24 +48,24 @@ module ActionDispatch
     end
 
     def if_modified_since=(last_modified)
-      set_header('HTTP_IF_MODIFIED_SINCE', last_modified)
+      set_header("HTTP_IF_MODIFIED_SINCE", last_modified)
     end
 
     def if_none_match=(etag)
-      set_header('HTTP_IF_NONE_MATCH', etag)
+      set_header("HTTP_IF_NONE_MATCH", etag)
     end
 
     def remote_addr=(addr)
-      set_header('REMOTE_ADDR', addr)
+      set_header("REMOTE_ADDR", addr)
     end
 
     def user_agent=(user_agent)
-      set_header('HTTP_USER_AGENT', user_agent)
+      set_header("HTTP_USER_AGENT", user_agent)
     end
 
     def accept=(mime_types)
-      delete_header('action_dispatch.request.accepts')
-      set_header('HTTP_ACCEPT', Array(mime_types).collect(&:to_s).join(","))
+      delete_header("action_dispatch.request.accepts")
+      set_header("HTTP_ACCEPT", Array(mime_types).collect(&:to_s).join(","))
     end
   end
 end
diff --git a/actionpack/lib/action_dispatch/testing/test_response.rb b/actionpack/lib/action_dispatch/testing/test_response.rb
index 9d4b73a43d..1e6b21f235 100644
--- a/actionpack/lib/action_dispatch/testing/test_response.rb
+++ b/actionpack/lib/action_dispatch/testing/test_response.rb
@@ -1,3 +1,7 @@
+# frozen_string_literal: true
+
+require "action_dispatch/testing/request_encoder"
+
 module ActionDispatch
   # Integration test methods such as ActionDispatch::Integration::Session#get
   # and ActionDispatch::Integration::Session#post return objects of class
@@ -10,16 +14,37 @@ module ActionDispatch
       new response.status, response.headers, response.body
     end
 
+    def initialize(*) # :nodoc:
+      super
+      @response_parser = RequestEncoder.parser(content_type)
+    end
+
     # Was the response successful?
-    alias_method :success?, :successful?
+    def success?
+      ActiveSupport::Deprecation.warn(<<-MSG.squish)
+       The success? predicate is deprecated and will be removed in Rails 6.0.
+       Please use successful? as provided by Rack::Response::Helpers.
+      MSG
+      successful?
+    end
 
     # Was the URL not found?
-    alias_method :missing?, :not_found?
+    def missing?
+      ActiveSupport::Deprecation.warn(<<-MSG.squish)
+       The missing? predicate is deprecated and will be removed in Rails 6.0.
+       Please use not_found? as provided by Rack::Response::Helpers.
+      MSG
+      not_found?
+    end
 
     # Was there a server-side error?
-    alias_method :error?, :server_error?
-
-    attr_writer :response_parser # :nodoc:
+    def error?
+      ActiveSupport::Deprecation.warn(<<-MSG.squish)
+       The error? predicate is deprecated and will be removed in Rails 6.0.
+       Please use server_error? as provided by Rack::Response::Helpers.
+      MSG
+      server_error?
+    end
 
     def parsed_body
       @parsed_body ||= @response_parser.call(body)
diff --git a/actionpack/lib/action_pack.rb b/actionpack/lib/action_pack.rb
index 941877d10d..3f69109633 100644
--- a/actionpack/lib/action_pack.rb
+++ b/actionpack/lib/action_pack.rb
@@ -1,5 +1,7 @@
+# frozen_string_literal: true
+
 #--
-# Copyright (c) 2004-2016 David Heinemeier Hansson
+# Copyright (c) 2004-2018 David Heinemeier Hansson
 #
 # Permission is hereby granted, free of charge, to any person obtaining
 # a copy of this software and associated documentation files (the
@@ -21,4 +23,4 @@
 # WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 #++
 
-require 'action_pack/version'
+require "action_pack/version"
diff --git a/actionpack/lib/action_pack/gem_version.rb b/actionpack/lib/action_pack/gem_version.rb
index d8f86630b1..97f4934b58 100644
--- a/actionpack/lib/action_pack/gem_version.rb
+++ b/actionpack/lib/action_pack/gem_version.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActionPack
   # Returns the version of the currently loaded Action Pack as a <tt>Gem::Version</tt>
   def self.gem_version
@@ -6,9 +8,9 @@ module ActionPack
 
   module VERSION
     MAJOR = 5
-    MINOR = 1
+    MINOR = 2
     TINY  = 0
-    PRE   = "alpha"
+    PRE   = "beta2"
 
     STRING = [MAJOR, MINOR, TINY, PRE].compact.join(".")
   end
diff --git a/actionpack/lib/action_pack/version.rb b/actionpack/lib/action_pack/version.rb
index 7088cd2760..fd039fe140 100644
--- a/actionpack/lib/action_pack/version.rb
+++ b/actionpack/lib/action_pack/version.rb
@@ -1,4 +1,6 @@
-require_relative 'gem_version'
+# frozen_string_literal: true
+
+require_relative "gem_version"
 
 module ActionPack
   # Returns the version of the currently loaded ActionPack as a <tt>Gem::Version</tt>
diff --git a/actionpack/test/abstract/callbacks_test.rb b/actionpack/test/abstract/callbacks_test.rb
index 07571602e4..fdc09bd951 100644
--- a/actionpack/test/abstract/callbacks_test.rb
+++ b/actionpack/test/abstract/callbacks_test.rb
@@ -1,8 +1,9 @@
-require 'abstract_unit'
+# frozen_string_literal: true
+
+require "abstract_unit"
 
 module AbstractController
   module Testing
-
     class ControllerWithCallbacks < AbstractController::Base
       include AbstractController::Callbacks
     end
@@ -43,7 +44,7 @@ module AbstractController
       def aroundz
         @aroundz = "FIRST"
         yield
-        @aroundz << "SECOND"
+        @aroundz += "SECOND"
       end
 
       def index
@@ -114,8 +115,8 @@ module AbstractController
     end
 
     class CallbacksWithConditions < ControllerWithCallbacks
-      before_action :list, :only => :index
-      before_action :authenticate, :except => :index
+      before_action :list, only: :index
+      before_action :authenticate, except: :index
 
       def index
         self.response_body = @list.join(", ")
@@ -126,14 +127,14 @@ module AbstractController
       end
 
       private
-      def list
-        @list = ["Hello", "World"]
-      end
-
-      def authenticate
-        @list ||= []
-        @authenticated = "true"
-      end
+        def list
+          @list = ["Hello", "World"]
+        end
+
+        def authenticate
+          @list ||= []
+          @authenticated = "true"
+        end
     end
 
     class TestCallbacksWithConditions < ActiveSupport::TestCase
@@ -170,14 +171,14 @@ module AbstractController
       end
 
       private
-      def list
-        @list = ["Hello", "World"]
-      end
-
-      def authenticate
-        @list = []
-        @authenticated = "true"
-      end
+        def list
+          @list = ["Hello", "World"]
+        end
+
+        def authenticate
+          @list = []
+          @authenticated = "true"
+        end
     end
 
     class TestCallbacksWithArrayConditions < ActiveSupport::TestCase
@@ -202,7 +203,7 @@ module AbstractController
     end
 
     class ChangedConditions < Callback2
-      before_action :first, :only => :index
+      before_action :first, only: :index
 
       def not_index
         @text ||= nil
@@ -265,53 +266,5 @@ module AbstractController
         assert_equal "Hello world Howdy!", controller.response_body
       end
     end
-
-    class AliasedCallbacks < ControllerWithCallbacks
-      ActiveSupport::Deprecation.silence do
-        before_filter :first
-        after_filter :second
-        around_filter :aroundz
-      end
-
-      def first
-        @text = "Hello world"
-      end
-
-      def second
-        @second = "Goodbye"
-      end
-
-      def aroundz
-        @aroundz = "FIRST"
-        yield
-        @aroundz << "SECOND"
-      end
-
-      def index
-        @text ||= nil
-        self.response_body = @text.to_s
-      end
-    end
-
-    class TestAliasedCallbacks < ActiveSupport::TestCase
-      def setup
-        @controller = AliasedCallbacks.new
-      end
-
-      test "before_filter works" do
-        @controller.process(:index)
-        assert_equal "Hello world", @controller.response_body
-      end
-
-      test "after_filter works" do
-        @controller.process(:index)
-        assert_equal "Goodbye", @controller.instance_variable_get("@second")
-      end
-
-      test "around_filter works" do
-        @controller.process(:index)
-        assert_equal "FIRSTSECOND", @controller.instance_variable_get("@aroundz")
-      end
-    end
   end
 end
diff --git a/actionpack/test/abstract/collector_test.rb b/actionpack/test/abstract/collector_test.rb
index edbb84d462..a4770b66e1 100644
--- a/actionpack/test/abstract/collector_test.rb
+++ b/actionpack/test/abstract/collector_test.rb
@@ -1,4 +1,6 @@
-require 'abstract_unit'
+# frozen_string_literal: true
+
+require "abstract_unit"
 
 module AbstractController
   module Testing
@@ -55,7 +57,7 @@ module AbstractController
         collector.js(:bar) { :baz }
         assert_equal [Mime[:html], [], nil], collector.responses[0]
         assert_equal [Mime[:text], [:foo], nil], collector.responses[1]
-        assert_equal [Mime[:js], [:bar]], collector.responses[2][0,2]
+        assert_equal [Mime[:js], [:bar]], collector.responses[2][0, 2]
         assert_equal :baz, collector.responses[2][2].call
       end
     end
diff --git a/actionpack/test/abstract/translation_test.rb b/actionpack/test/abstract/translation_test.rb
index 1435928578..7138044c03 100644
--- a/actionpack/test/abstract/translation_test.rb
+++ b/actionpack/test/abstract/translation_test.rb
@@ -1,4 +1,6 @@
-require 'abstract_unit'
+# frozen_string_literal: true
+
+require "abstract_unit"
 
 module AbstractController
   module Testing
@@ -9,21 +11,20 @@ module AbstractController
     class TranslationControllerTest < ActiveSupport::TestCase
       def setup
         @controller = TranslationController.new
-        I18n.backend.store_translations(:en, {
+        I18n.backend.store_translations(:en,
           one: {
-            two: 'bar',
+            two: "bar",
           },
           abstract_controller: {
             testing: {
               translation: {
                 index: {
-                  foo: 'bar',
+                  foo: "bar",
                 },
-                no_action: 'no_action_tr',
+                no_action: "no_action_tr",
               },
             },
-          },
-        })
+          })
       end
 
       def test_action_controller_base_responds_to_translate
@@ -44,30 +45,31 @@ module AbstractController
 
       def test_lazy_lookup
         @controller.stub :action_name, :index do
-          assert_equal 'bar', @controller.t('.foo')
+          assert_equal "bar", @controller.t(".foo")
         end
       end
 
       def test_lazy_lookup_with_symbol
         @controller.stub :action_name, :index do
-          assert_equal 'bar', @controller.t(:'.foo')
+          assert_equal "bar", @controller.t(:'.foo')
         end
       end
 
       def test_lazy_lookup_fallback
         @controller.stub :action_name, :index do
-          assert_equal 'no_action_tr', @controller.t(:'.no_action')
+          assert_equal "no_action_tr", @controller.t(:'.no_action')
         end
       end
 
       def test_default_translation
         @controller.stub :action_name, :index do
-          assert_equal 'bar', @controller.t('one.two')
+          assert_equal "bar", @controller.t("one.two")
+          assert_equal "baz", @controller.t(".twoz", default: ["baz", :twoz])
         end
       end
 
       def test_localize
-        time, expected = Time.gm(2000), 'Sat, 01 Jan 2000 00:00:00 +0000'
+        time, expected = Time.gm(2000), "Sat, 01 Jan 2000 00:00:00 +0000"
         I18n.stub :localize, expected do
           assert_equal expected, @controller.l(time)
         end
diff --git a/actionpack/test/abstract_unit.rb b/actionpack/test/abstract_unit.rb
index 1e1d6f5429..f4787ed27a 100644
--- a/actionpack/test/abstract_unit.rb
+++ b/actionpack/test/abstract_unit.rb
@@ -1,41 +1,42 @@
-$:.unshift(File.dirname(__FILE__) + '/lib')
-$:.unshift(File.dirname(__FILE__) + '/fixtures/helpers')
-$:.unshift(File.dirname(__FILE__) + '/fixtures/alternate_helpers')
+# frozen_string_literal: true
 
-require 'active_support/core_ext/kernel/reporting'
+$:.unshift File.expand_path("lib", __dir__)
+$:.unshift File.expand_path("fixtures/helpers", __dir__)
+$:.unshift File.expand_path("fixtures/alternate_helpers", __dir__)
+
+require "active_support/core_ext/kernel/reporting"
 
 # These are the normal settings that will be set up by Railties
 # TODO: Have these tests support other combinations of these values
 silence_warnings do
-  Encoding.default_internal = "UTF-8"
-  Encoding.default_external = "UTF-8"
+  Encoding.default_internal = Encoding::UTF_8
+  Encoding.default_external = Encoding::UTF_8
 end
 
-require 'drb'
+require "drb"
 begin
-  require 'drb/unix'
+  require "drb/unix"
 rescue LoadError
   puts "'drb/unix' is not available"
 end
 
-if ENV['TRAVIS']
+if ENV["TRAVIS"]
   PROCESS_COUNT = 0
 else
-  PROCESS_COUNT = (ENV['N'] || 4).to_i
+  PROCESS_COUNT = (ENV["N"] || 4).to_i
 end
 
-require 'active_support/testing/autorun'
-require 'abstract_controller'
-require 'abstract_controller/railties/routes_helpers'
-require 'action_controller'
-require 'action_view'
-require 'action_view/testing/resolvers'
-require 'action_dispatch'
-require 'active_support/dependencies'
-require 'active_model'
-require 'active_record'
+require "active_support/testing/autorun"
+require "abstract_controller"
+require "abstract_controller/railties/routes_helpers"
+require "action_controller"
+require "action_view"
+require "action_view/testing/resolvers"
+require "action_dispatch"
+require "active_support/dependencies"
+require "active_model"
 
-require 'pp' # require 'pp' early to prevent hidden_methods from not picking up the pretty-print methods until too late
+require "pp" # require 'pp' early to prevent hidden_methods from not picking up the pretty-print methods until too late
 
 module Rails
   class << self
@@ -43,7 +44,7 @@ module Rails
       @_env ||= ActiveSupport::StringInquirer.new(ENV["RAILS_ENV"] || ENV["RACK_ENV"] || "test")
     end
 
-    def root; end;
+    def root; end
   end
 end
 
@@ -57,13 +58,13 @@ ActiveSupport::Deprecation.debug = true
 # Disable available locale checks to avoid warnings running the test suite.
 I18n.enforce_available_locales = false
 
-FIXTURE_LOAD_PATH = File.join(File.dirname(__FILE__), 'fixtures')
+FIXTURE_LOAD_PATH = File.join(__dir__, "fixtures")
 
 SharedTestRoutes = ActionDispatch::Routing::RouteSet.new
 
 SharedTestRoutes.draw do
   ActiveSupport::Deprecation.silence do
-    get ':controller(/:action)'
+    get ":controller(/:action)"
   end
 end
 
@@ -105,6 +106,7 @@ class ActionDispatch::IntegrationTest < ActiveSupport::TestCase
       middleware.use ActionDispatch::Callbacks
       middleware.use ActionDispatch::Cookies
       middleware.use ActionDispatch::Flash
+      middleware.use Rack::MethodOverride
       middleware.use Rack::Head
       yield(middleware) if block_given?
     end
@@ -114,7 +116,7 @@ class ActionDispatch::IntegrationTest < ActiveSupport::TestCase
 
   app.routes.draw do
     ActiveSupport::Deprecation.silence do
-      get ':controller(/:action)'
+      get ":controller(/:action)"
     end
   end
 
@@ -122,27 +124,19 @@ class ActionDispatch::IntegrationTest < ActiveSupport::TestCase
     # Stub Rails dispatcher so it does not get controller references and
     # simply return the controller#action as Rack::Body.
     class NullController < ::ActionController::Metal
-      def initialize(controller_name)
-        @controller = controller_name
-      end
-
-      def make_response!(request)
-        self.class.make_response! request
-      end
-
-      def dispatch(action, req, res)
-        [200, {'Content-Type' => 'text/html'}, ["#{@controller}##{action}"]]
+      def self.dispatch(action, req, res)
+        [200, { "Content-Type" => "text/html" }, ["#{req.params[:controller]}##{action}"]]
       end
     end
 
-    class NullControllerRequest < DelegateClass(ActionDispatch::Request)
+    class NullControllerRequest < ActionDispatch::Request
       def controller_class
-        NullController.new params[:controller]
+        NullController
       end
     end
 
-    def make_request env
-      NullControllerRequest.new super
+    def make_request(env)
+      NullControllerRequest.new env
     end
   end
 
@@ -159,12 +153,12 @@ class ActionDispatch::IntegrationTest < ActiveSupport::TestCase
     yield temporary_routes
   ensure
     self.class.app = old_app
-    self.remove!
+    remove!
     silence_warnings { Object.const_set(:SharedTestRoutes, old_routes) }
   end
 
   def with_autoload_path(path)
-    path = File.join(File.dirname(__FILE__), "fixtures", path)
+    path = File.join(__dir__, "fixtures", path)
     if ActiveSupport::Dependencies.autoload_paths.include?(path)
       yield
     else
@@ -172,7 +166,7 @@ class ActionDispatch::IntegrationTest < ActiveSupport::TestCase
         ActiveSupport::Dependencies.autoload_paths << path
         yield
       ensure
-        ActiveSupport::Dependencies.autoload_paths.reject! {|p| p == path}
+        ActiveSupport::Dependencies.autoload_paths.reject! { |p| p == path }
         ActiveSupport::Dependencies.clear
       end
     end
@@ -183,7 +177,7 @@ end
 class Rack::TestCase < ActionDispatch::IntegrationTest
   def self.testing(klass = nil)
     if klass
-      @testing = "/#{klass.name.underscore}".sub!(/_controller$/, '')
+      @testing = "/#{klass.name.underscore}".sub(/_controller$/, "")
     else
       @testing
     end
@@ -247,18 +241,17 @@ module ActionController
   end
 end
 
-
 class ::ApplicationController < ActionController::Base
 end
 
 module ActionDispatch
   class DebugExceptions
     private
-    remove_method :stderr_logger
-    # Silence logger
-    def stderr_logger
-      nil
-    end
+      remove_method :stderr_logger
+      # Silence logger
+      def stderr_logger
+        nil
+      end
   end
 end
 
@@ -268,16 +261,16 @@ module ActionDispatch
       host = uri_or_host.host unless path
       path ||= uri_or_host.path
 
-      params = {'PATH_INFO'      => path,
-                'REQUEST_METHOD' => method,
-                'HTTP_HOST'      => host}
+      params = { "PATH_INFO" => path,
+                 "REQUEST_METHOD" => method,
+                 "HTTP_HOST" => host }
 
       routes.call(params)
     end
 
     def request_path_params(path, options = {})
-      method = options[:method] || 'GET'
-      resp = send_request URI('http://localhost' + path), method.to_s.upcase, nil
+      method = options[:method] || "GET"
+      resp = send_request URI("http://localhost" + path), method.to_s.upcase, nil
       status = resp.first
       if status == 404
         raise ActionController::RoutingError, "No route matches #{path.inspect}"
@@ -286,23 +279,23 @@ module ActionDispatch
     end
 
     def get(uri_or_host, path = nil)
-      send_request(uri_or_host, 'GET', path)[2].join
+      send_request(uri_or_host, "GET", path)[2].join
     end
 
     def post(uri_or_host, path = nil)
-      send_request(uri_or_host, 'POST', path)[2].join
+      send_request(uri_or_host, "POST", path)[2].join
     end
 
     def put(uri_or_host, path = nil)
-      send_request(uri_or_host, 'PUT', path)[2].join
+      send_request(uri_or_host, "PUT", path)[2].join
     end
 
     def delete(uri_or_host, path = nil)
-      send_request(uri_or_host, 'DELETE', path)[2].join
+      send_request(uri_or_host, "DELETE", path)[2].join
     end
 
     def patch(uri_or_host, path = nil)
-      send_request(uri_or_host, 'PATCH', path)[2].join
+      send_request(uri_or_host, "PATCH", path)[2].join
     end
   end
 end
@@ -310,7 +303,7 @@ end
 module RoutingTestHelpers
   def url_for(set, options)
     route_name = options.delete :use_route
-    set.url_for options.merge(:only_path => true), route_name
+    set.url_for options.merge(only_path: true), route_name
   end
 
   def make_set(strict = true)
@@ -348,9 +341,9 @@ module RoutingTestHelpers
 
     private
 
-    def make_request(env)
-      Request.new super, url_helpers, @block, strict
-    end
+      def make_request(env)
+        Request.new super, url_helpers, @block, strict
+      end
   end
 end
 
@@ -360,19 +353,10 @@ class ResourcesController < ActionController::Base
 end
 
 class CommentsController < ResourcesController; end
-class AccountsController <  ResourcesController; end
+class AccountsController < ResourcesController; end
 class ImagesController < ResourcesController; end
 
-# Skips the current run on Rubinius using Minitest::Assertions#skip
-def rubinius_skip(message = '')
-  skip message if RUBY_ENGINE == 'rbx'
-end
-# Skips the current run on JRuby using Minitest::Assertions#skip
-def jruby_skip(message = '')
-  skip message if defined?(JRUBY_VERSION)
-end
-
-require 'active_support/testing/method_call_assertions'
+require "active_support/testing/method_call_assertions"
 
 class ForkingExecutor
   class Server
@@ -382,27 +366,25 @@ class ForkingExecutor
       @queue = Queue.new
     end
 
-    def record reporter, result
+    def record(reporter, result)
       reporter.record result
     end
 
-    def << o
+    def <<(o)
       o[2] = DRbObject.new(o[2]) if o
       @queue << o
     end
     def pop; @queue.pop; end
   end
 
-  def initialize size
+  def initialize(size)
     @size  = size
     @queue = Server.new
-    file   = File.join Dir.tmpdir, Dir::Tmpname.make_tmpname('rails-tests', 'fd')
-    @url   = "drbunix://#{file}"
     @pool  = nil
-    DRb.start_service @url, @queue
+    @url = DRb.start_service("drbunix:", @queue).uri
   end
 
-  def << work; @queue << work; end
+  def <<(work); @queue << work; end
 
   def shutdown
     pool = @size.times.map {
@@ -426,18 +408,18 @@ class ForkingExecutor
   end
 
   private
-  def translate_exceptions(result)
-    result.failures.map! { |e|
-      begin
-        Marshal.dump e
-        e
-      rescue TypeError
-        ex = Exception.new e.message
-        ex.set_backtrace e.backtrace
-        Minitest::UnexpectedError.new ex
-      end
-    }
-  end
+    def translate_exceptions(result)
+      result.failures.map! { |e|
+        begin
+          Marshal.dump e
+          e
+        rescue TypeError
+          ex = Exception.new e.message
+          ex.set_backtrace e.backtrace
+          Minitest::UnexpectedError.new ex
+        end
+      }
+    end
 end
 
 if RUBY_ENGINE == "ruby" && PROCESS_COUNT > 0
@@ -447,4 +429,29 @@ end
 
 class ActiveSupport::TestCase
   include ActiveSupport::Testing::MethodCallAssertions
+
+  # Skips the current run on Rubinius using Minitest::Assertions#skip
+  private def rubinius_skip(message = "")
+    skip message if RUBY_ENGINE == "rbx"
+  end
+  # Skips the current run on JRuby using Minitest::Assertions#skip
+  private def jruby_skip(message = "")
+    skip message if defined?(JRUBY_VERSION)
+  end
+end
+
+class DrivenByRackTest < ActionDispatch::SystemTestCase
+  driven_by :rack_test
+end
+
+class DrivenBySeleniumWithChrome < ActionDispatch::SystemTestCase
+  driven_by :selenium, using: :chrome
+end
+
+class DrivenBySeleniumWithHeadlessChrome < ActionDispatch::SystemTestCase
+  driven_by :selenium, using: :headless_chrome
+end
+
+class DrivenBySeleniumWithHeadlessFirefox < ActionDispatch::SystemTestCase
+  driven_by :selenium, using: :headless_firefox
 end
diff --git a/actionpack/test/assertions/response_assertions_test.rb b/actionpack/test/assertions/response_assertions_test.rb
index 57a67a48b5..261579dce5 100644
--- a/actionpack/test/assertions/response_assertions_test.rb
+++ b/actionpack/test/assertions/response_assertions_test.rb
@@ -1,15 +1,18 @@
-require 'abstract_unit'
-require 'action_dispatch/testing/assertions/response'
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "action_dispatch/testing/assertions/response"
 
 module ActionDispatch
   module Assertions
     class ResponseAssertionsTest < ActiveSupport::TestCase
       include ResponseAssertions
 
-      FakeResponse = Struct.new(:response_code, :location) do
+      FakeResponse = Struct.new(:response_code, :location, :body) do
         def initialize(*)
           super
           self.location ||= "http://test.example.com/posts"
+          self.body ||= ""
         end
 
         [:successful, :not_found, :redirection, :server_error].each do |sym|
@@ -26,7 +29,7 @@ module ActionDispatch
 
       def test_assert_response_predicate_methods
         [:success, :missing, :redirect, :error].each do |sym|
-          @response = FakeResponse.new RESPONSE_PREDICATES[sym].to_s.sub(/\?/, '').to_sym
+          @response = FakeResponse.new RESPONSE_PREDICATES[sym].to_s.sub(/\?/, "").to_sym
           assert_response sym
 
           assert_raises(Minitest::Assertion) {
@@ -92,7 +95,7 @@ module ActionDispatch
       def test_error_message_shows_302_redirect_when_302_asserted_for_success
         @response = ActionDispatch::Response.new
         @response.status = 302
-        @response.location = 'http://test.host/posts/redirect/1'
+        @response.location = "http://test.host/posts/redirect/1"
 
         error = assert_raises(Minitest::Assertion) { assert_response :success }
         expected = "Expected response to be a <2XX: success>,"\
@@ -104,7 +107,7 @@ module ActionDispatch
       def test_error_message_shows_302_redirect_when_302_asserted_for_301
         @response = ActionDispatch::Response.new
         @response.status = 302
-        @response.location = 'http://test.host/posts/redirect/2'
+        @response.location = "http://test.host/posts/redirect/2"
 
         error = assert_raises(Minitest::Assertion) { assert_response 301 }
         expected = "Expected response to be a <301: Moved Permanently>,"\
@@ -112,6 +115,27 @@ module ActionDispatch
                    " redirect to <http://test.host/posts/redirect/2>"
         assert_match expected, error.message
       end
+
+      def test_error_message_shows_short_response_body
+        @response = ActionDispatch::Response.new
+        @response.status = 400
+        @response.body = "not too long"
+        error = assert_raises(Minitest::Assertion) { assert_response 200 }
+        expected = "Expected response to be a <200: OK>,"\
+                   " but was a <400: Bad Request>" \
+                   "\nResponse body: not too long"
+        assert_match expected, error.message
+      end
+
+      def test_error_message_does_not_show_long_response_body
+        @response = ActionDispatch::Response.new
+        @response.status = 400
+        @response.body = "not too long" * 50
+        error = assert_raises(Minitest::Assertion) { assert_response 200 }
+        expected = "Expected response to be a <200: OK>,"\
+                   " but was a <400: Bad Request>"
+        assert_match expected, error.message
+      end
     end
   end
 end
diff --git a/actionpack/test/controller/action_pack_assertions_test.rb b/actionpack/test/controller/action_pack_assertions_test.rb
index db71aa2160..f9a037e3cc 100644
--- a/actionpack/test/controller/action_pack_assertions_test.rb
+++ b/actionpack/test/controller/action_pack_assertions_test.rb
@@ -1,33 +1,34 @@
-require 'abstract_unit'
-require 'controller/fake_controllers'
+# frozen_string_literal: true
 
-class ActionPackAssertionsController < ActionController::Base
+require "abstract_unit"
+require "controller/fake_controllers"
 
+class ActionPackAssertionsController < ActionController::Base
   def nothing() head :ok end
 
-  def hello_xml_world() render :template => "test/hello_xml_world"; end
+  def hello_xml_world() render template: "test/hello_xml_world"; end
 
   def hello_xml_world_pdf
     self.content_type = "application/pdf"
-    render :template => "test/hello_xml_world"
+    render template: "test/hello_xml_world"
   end
 
   def hello_xml_world_pdf_header
     response.headers["Content-Type"] = "application/pdf; charset=utf-8"
-    render :template => "test/hello_xml_world"
+    render template: "test/hello_xml_world"
   end
 
   def redirect_internal() redirect_to "/nothing"; end
 
-  def redirect_to_action() redirect_to :action => "flash_me", :id => 1, :params => { "panda" => "fun" }; end
+  def redirect_to_action() redirect_to action: "flash_me", id: 1, params: { "panda" => "fun" }; end
 
-  def redirect_to_controller() redirect_to :controller => "elsewhere", :action => "flash_me"; end
+  def redirect_to_controller() redirect_to controller: "elsewhere", action: "flash_me"; end
 
-  def redirect_to_controller_with_symbol() redirect_to :controller => :elsewhere, :action => :flash_me; end
+  def redirect_to_controller_with_symbol() redirect_to controller: :elsewhere, action: :flash_me; end
 
-  def redirect_to_path() redirect_to '/some/path' end
+  def redirect_to_path() redirect_to "/some/path" end
 
-  def redirect_invalid_external_route() redirect_to 'ht_tp://www.rubyonrails.org' end
+  def redirect_invalid_external_route() redirect_to "ht_tp://www.rubyonrails.org" end
 
   def redirect_to_named_route() redirect_to route_one_url end
 
@@ -35,14 +36,14 @@ class ActionPackAssertionsController < ActionController::Base
 
   def redirect_external_protocol_relative() redirect_to "//www.rubyonrails.org"; end
 
-  def response404() head '404 AWOL' end
+  def response404() head "404 AWOL" end
 
-  def response500() head '500 Sorry' end
+  def response500() head "500 Sorry" end
 
-  def response599() head '599 Whoah!' end
+  def response599() head "599 Whoah!" end
 
   def flash_me
-    flash['hello'] = 'my name is inigo montoya...'
+    flash["hello"] = "my name is inigo montoya..."
     render plain: "Inconceivable!"
   end
 
@@ -53,7 +54,7 @@ class ActionPackAssertionsController < ActionController::Base
 
   def assign_this
     @howdy = "ho"
-    render :inline => "Mr. Henke"
+    render inline: "Mr. Henke"
   end
 
   def render_based_on_parameters
@@ -69,7 +70,7 @@ class ActionPackAssertionsController < ActionController::Base
   end
 
   def session_stuffing
-    session['xmas'] = 'turkey'
+    session["xmas"] = "turkey"
     render plain: "ho ho ho"
   end
 
@@ -84,11 +85,11 @@ class ActionPackAssertionsController < ActionController::Base
   end
 
   def render_file_absolute_path
-    render :file => File.expand_path('../../../README.rdoc', __FILE__)
+    render file: File.expand_path("../../README.rdoc", __dir__)
   end
 
   def render_file_relative_path
-    render :file => 'README.rdoc'
+    render file: "README.rdoc"
   end
 end
 
@@ -97,7 +98,7 @@ end
 # is expecting something other than an error.
 class AssertResponseWithUnexpectedErrorController < ActionController::Base
   def index
-    raise 'FAIL'
+    raise "FAIL"
   end
 
   def show
@@ -116,21 +117,30 @@ module Admin
     end
 
     def redirect_to_absolute_controller
-      redirect_to :controller => '/content'
+      redirect_to controller: "/content"
     end
 
     def redirect_to_fellow_controller
-      redirect_to :controller => 'user'
+      redirect_to controller: "user"
     end
 
     def redirect_to_top_level_named_route
-      redirect_to top_level_url(:id => "foo")
+      redirect_to top_level_url(id: "foo")
     end
   end
 end
 
-class ActionPackAssertionsControllerTest < ActionController::TestCase
+class ApiOnlyController < ActionController::API
+  def nothing
+    head :ok
+  end
 
+  def redirect_to_new_route
+    redirect_to new_route_url
+  end
+end
+
+class ActionPackAssertionsControllerTest < ActionController::TestCase
   def test_render_file_absolute_path
     get :render_file_absolute_path
     assert_match(/\A= Action Pack/, @response.body)
@@ -144,53 +154,67 @@ class ActionPackAssertionsControllerTest < ActionController::TestCase
   def test_get_request
     assert_raise(RuntimeError) { get :raise_exception_on_get }
     get :raise_exception_on_post
-    assert_equal 'request method: GET', @response.body
+    assert_equal "request method: GET", @response.body
   end
 
   def test_post_request
     assert_raise(RuntimeError) { post :raise_exception_on_post }
     post :raise_exception_on_get
-    assert_equal 'request method: POST', @response.body
+    assert_equal "request method: POST", @response.body
   end
 
   def test_get_post_request_switch
     post :raise_exception_on_get
-    assert_equal 'request method: POST', @response.body
+    assert_equal "request method: POST", @response.body
     get :raise_exception_on_post
-    assert_equal 'request method: GET', @response.body
+    assert_equal "request method: GET", @response.body
     post :raise_exception_on_get
-    assert_equal 'request method: POST', @response.body
+    assert_equal "request method: POST", @response.body
     get :raise_exception_on_post
-    assert_equal 'request method: GET', @response.body
+    assert_equal "request method: GET", @response.body
   end
 
   def test_string_constraint
     with_routing do |set|
       set.draw do
-        get "photos", :to => 'action_pack_assertions#nothing', :constraints => {:subdomain => "admin"}
+        get "photos", to: "action_pack_assertions#nothing", constraints: { subdomain: "admin" }
       end
     end
   end
 
+  def test_with_routing_works_with_api_only_controllers
+    @controller = ApiOnlyController.new
+
+    with_routing do |set|
+      set.draw do
+        get "new_route", to: "api_only#nothing"
+        get "redirect_to_new_route", to: "api_only#redirect_to_new_route"
+      end
+
+      process :redirect_to_new_route
+      assert_redirected_to "http://test.host/new_route"
+    end
+  end
+
   def test_assert_redirect_to_named_route_failure
     with_routing do |set|
       set.draw do
-        get 'route_one', :to => 'action_pack_assertions#nothing', :as => :route_one
-        get 'route_two', :to => 'action_pack_assertions#nothing', :id => 'two', :as => :route_two
+        get "route_one", to: "action_pack_assertions#nothing", as: :route_one
+        get "route_two", to: "action_pack_assertions#nothing", id: "two", as: :route_two
 
         ActiveSupport::Deprecation.silence do
-          get ':controller/:action'
+          get ":controller/:action"
         end
       end
       process :redirect_to_named_route
       assert_raise(ActiveSupport::TestCase::Assertion) do
-        assert_redirected_to 'http://test.host/route_two'
+        assert_redirected_to "http://test.host/route_two"
       end
       assert_raise(ActiveSupport::TestCase::Assertion) do
         assert_redirected_to %r(^http://test.host/route_two)
       end
       assert_raise(ActiveSupport::TestCase::Assertion) do
-        assert_redirected_to :controller => 'action_pack_assertions', :action => 'nothing', :id => 'two'
+        assert_redirected_to controller: "action_pack_assertions", action: "nothing", id: "two"
       end
       assert_raise(ActiveSupport::TestCase::Assertion) do
         assert_redirected_to route_two_url
@@ -203,10 +227,10 @@ class ActionPackAssertionsControllerTest < ActionController::TestCase
 
     with_routing do |set|
       set.draw do
-        get 'admin/inner_module', :to => 'admin/inner_module#index', :as => :admin_inner_module
+        get "admin/inner_module", to: "admin/inner_module#index", as: :admin_inner_module
 
         ActiveSupport::Deprecation.silence do
-          get ':controller/:action'
+          get ":controller/:action"
         end
       end
       process :redirect_to_index
@@ -220,10 +244,10 @@ class ActionPackAssertionsControllerTest < ActionController::TestCase
 
     with_routing do |set|
       set.draw do
-        get '/action_pack_assertions/:id', :to => 'action_pack_assertions#index', :as => :top_level
+        get "/action_pack_assertions/:id", to: "action_pack_assertions#index", as: :top_level
 
         ActiveSupport::Deprecation.silence do
-          get ':controller/:action'
+          get ":controller/:action"
         end
       end
       process :redirect_to_top_level_named_route
@@ -239,15 +263,15 @@ class ActionPackAssertionsControllerTest < ActionController::TestCase
     with_routing do |set|
       set.draw do
         # this controller exists in the admin namespace as well which is the only difference from previous test
-        get '/user/:id', :to => 'user#index', :as => :top_level
+        get "/user/:id", to: "user#index", as: :top_level
 
         ActiveSupport::Deprecation.silence do
-          get ':controller/:action'
+          get ":controller/:action"
         end
       end
       process :redirect_to_top_level_named_route
       # assert_redirected_to top_level_url('foo') would pass because of exact match early return
-      assert_redirected_to top_level_path('foo')
+      assert_redirected_to top_level_path("foo")
     end
   end
 
@@ -259,7 +283,7 @@ class ActionPackAssertionsControllerTest < ActionController::TestCase
       assert_no_match(
         /#{request.protocol}#{request.host}\/\/www.rubyonrails.org/,
         ex.message,
-        'protocol relative url was incorrectly normalized'
+        "protocol relative url was incorrectly normalized"
       )
     end
   end
@@ -283,7 +307,7 @@ class ActionPackAssertionsControllerTest < ActionController::TestCase
   def test_flash_exist
     process :flash_me
     assert flash.any?
-    assert flash['hello'].present?
+    assert flash["hello"].present?
   end
 
   def test_flash_does_not_exist
@@ -293,7 +317,7 @@ class ActionPackAssertionsControllerTest < ActionController::TestCase
 
   def test_session_exist
     process :session_stuffing
-    assert_equal 'turkey', session['xmas']
+    assert_equal "turkey", session["xmas"]
   end
 
   def session_does_not_exist
@@ -303,13 +327,13 @@ class ActionPackAssertionsControllerTest < ActionController::TestCase
 
   def test_redirection_location
     process :redirect_internal
-    assert_equal 'http://test.host/nothing', @response.redirect_url
+    assert_equal "http://test.host/nothing", @response.redirect_url
 
     process :redirect_external
-    assert_equal 'http://www.rubyonrails.org', @response.redirect_url
+    assert_equal "http://www.rubyonrails.org", @response.redirect_url
 
     process :redirect_external_protocol_relative
-    assert_equal '//www.rubyonrails.org', @response.redirect_url
+    assert_equal "//www.rubyonrails.org", @response.redirect_url
   end
 
   def test_no_redirect_url
@@ -376,24 +400,24 @@ class ActionPackAssertionsControllerTest < ActionController::TestCase
   def test_assert_redirection_fails_with_incorrect_controller
     process :redirect_to_controller
     assert_raise(ActiveSupport::TestCase::Assertion) do
-      assert_redirected_to :controller => "action_pack_assertions", :action => "flash_me"
+      assert_redirected_to controller: "action_pack_assertions", action: "flash_me"
     end
   end
 
   def test_assert_redirection_with_extra_controller_option
     get :redirect_to_action
-    assert_redirected_to :controller => 'action_pack_assertions', :action => "flash_me", :id => 1, :params => { :panda => 'fun' }
+    assert_redirected_to controller: "action_pack_assertions", action: "flash_me", id: 1, params: { panda: "fun" }
   end
 
   def test_redirected_to_url_leading_slash
     process :redirect_to_path
-    assert_redirected_to '/some/path'
+    assert_redirected_to "/some/path"
   end
 
   def test_redirected_to_url_no_leading_slash_fails
     process :redirect_to_path
     assert_raise ActiveSupport::TestCase::Assertion do
-      assert_redirected_to 'some/path'
+      assert_redirected_to "some/path"
     end
   end
 
@@ -404,43 +428,43 @@ class ActionPackAssertionsControllerTest < ActionController::TestCase
 
   def test_redirected_to_url_full_url
     process :redirect_to_path
-    assert_redirected_to 'http://test.host/some/path'
+    assert_redirected_to "http://test.host/some/path"
   end
 
   def test_assert_redirection_with_symbol
     process :redirect_to_controller_with_symbol
     assert_nothing_raised {
-      assert_redirected_to :controller => "elsewhere", :action => "flash_me"
+      assert_redirected_to controller: "elsewhere", action: "flash_me"
     }
     process :redirect_to_controller_with_symbol
     assert_nothing_raised {
-      assert_redirected_to :controller => :elsewhere, :action => :flash_me
+      assert_redirected_to controller: :elsewhere, action: :flash_me
     }
   end
 
   def test_redirected_to_with_nested_controller
     @controller = Admin::InnerModuleController.new
     get :redirect_to_absolute_controller
-    assert_redirected_to :controller => '/content'
+    assert_redirected_to controller: "/content"
 
     get :redirect_to_fellow_controller
-    assert_redirected_to :controller => 'admin/user'
+    assert_redirected_to controller: "admin/user"
   end
 
   def test_assert_response_uses_exception_message
     @controller = AssertResponseWithUnexpectedErrorController.new
-    e = assert_raise RuntimeError, 'Expected non-success response' do
+    e = assert_raise RuntimeError, "Expected non-success response" do
       get :index
     end
     assert_response :success
-    assert_includes 'FAIL', e.message
+    assert_includes "FAIL", e.message
   end
 
   def test_assert_response_failure_response_with_no_exception
     @controller = AssertResponseWithUnexpectedErrorController.new
     get :show
     assert_response 500
-    assert_equal 'Boom', response.body
+    assert_equal "Boom", response.body
   end
 end
 
@@ -449,21 +473,21 @@ class ActionPackHeaderTest < ActionController::TestCase
 
   def test_rendering_xml_sets_content_type
     process :hello_xml_world
-    assert_equal('application/xml; charset=utf-8', @response.headers['Content-Type'])
+    assert_equal("application/xml; charset=utf-8", @response.headers["Content-Type"])
   end
 
   def test_rendering_xml_respects_content_type
     process :hello_xml_world_pdf
-    assert_equal('application/pdf; charset=utf-8', @response.headers['Content-Type'])
+    assert_equal("application/pdf; charset=utf-8", @response.headers["Content-Type"])
   end
 
   def test_rendering_xml_respects_content_type_when_set_in_the_header
     process :hello_xml_world_pdf_header
-    assert_equal('application/pdf; charset=utf-8', @response.headers['Content-Type'])
+    assert_equal("application/pdf; charset=utf-8", @response.headers["Content-Type"])
   end
 
   def test_render_text_with_custom_content_type
     get :render_text_with_custom_content_type
-    assert_equal 'application/rss+xml; charset=utf-8', @response.headers['Content-Type']
+    assert_equal "application/rss+xml; charset=utf-8", @response.headers["Content-Type"]
   end
 end
diff --git a/actionpack/test/controller/api/conditional_get_test.rb b/actionpack/test/controller/api/conditional_get_test.rb
index b4f1673be0..fd1997f26c 100644
--- a/actionpack/test/controller/api/conditional_get_test.rb
+++ b/actionpack/test/controller/api/conditional_get_test.rb
@@ -1,6 +1,8 @@
-require 'abstract_unit'
-require 'active_support/core_ext/integer/time'
-require 'active_support/core_ext/numeric/time'
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "active_support/core_ext/integer/time"
+require "active_support/core_ext/numeric/time"
 
 class ConditionalGetApiController < ActionController::API
   before_action :handle_last_modified_and_etags, only: :two
@@ -17,9 +19,9 @@ class ConditionalGetApiController < ActionController::API
 
   private
 
-  def handle_last_modified_and_etags
-    fresh_when(last_modified: Time.now.utc.beginning_of_day, etag: [ :foo, 123 ])
-  end
+    def handle_last_modified_and_etags
+      fresh_when(last_modified: Time.now.utc.beginning_of_day, etag: [ :foo, 123 ])
+    end
 end
 
 class ConditionalGetApiTest < ActionController::TestCase
@@ -31,7 +33,7 @@ class ConditionalGetApiTest < ActionController::TestCase
 
   def test_request_gets_last_modified
     get :two
-    assert_equal @last_modified, @response.headers['Last-Modified']
+    assert_equal @last_modified, @response.headers["Last-Modified"]
     assert_response :success
   end
 
@@ -52,6 +54,6 @@ class ConditionalGetApiTest < ActionController::TestCase
     get :one
     assert_equal 304, @response.status.to_i
     assert @response.body.blank?
-    assert_equal @last_modified, @response.headers['Last-Modified']
+    assert_equal @last_modified, @response.headers["Last-Modified"]
   end
 end
diff --git a/actionpack/test/controller/api/data_streaming_test.rb b/actionpack/test/controller/api/data_streaming_test.rb
index 0e7d97d1f4..6446ff9e40 100644
--- a/actionpack/test/controller/api/data_streaming_test.rb
+++ b/actionpack/test/controller/api/data_streaming_test.rb
@@ -1,8 +1,10 @@
-require 'abstract_unit'
+# frozen_string_literal: true
+
+require "abstract_unit"
 
 module TestApiFileUtils
-  def file_path() File.expand_path(__FILE__) end
-  def file_data() @data ||= File.open(file_path, 'rb') { |f| f.read } end
+  def file_path() __FILE__ end
+  def file_data() @data ||= File.open(file_path, "rb") { |f| f.read } end
 end
 
 class DataStreamingApiController < ActionController::API
@@ -19,7 +21,7 @@ class DataStreamingApiTest < ActionController::TestCase
   tests DataStreamingApiController
 
   def test_data
-    response = process('two')
+    response = process("two")
     assert_kind_of String, response.body
     assert_equal file_data, response.body
   end
diff --git a/actionpack/test/controller/api/force_ssl_test.rb b/actionpack/test/controller/api/force_ssl_test.rb
index 8578340d82..07459c3753 100644
--- a/actionpack/test/controller/api/force_ssl_test.rb
+++ b/actionpack/test/controller/api/force_ssl_test.rb
@@ -1,4 +1,6 @@
-require 'abstract_unit'
+# frozen_string_literal: true
+
+require "abstract_unit"
 
 class ForceSSLApiController < ActionController::API
   force_ssl
diff --git a/actionpack/test/controller/api/implicit_render_test.rb b/actionpack/test/controller/api/implicit_render_test.rb
index 26f9cd8f78..288fb333b0 100644
--- a/actionpack/test/controller/api/implicit_render_test.rb
+++ b/actionpack/test/controller/api/implicit_render_test.rb
@@ -1,4 +1,6 @@
-require 'abstract_unit'
+# frozen_string_literal: true
+
+require "abstract_unit"
 
 class ImplicitRenderAPITestController < ActionController::API
   def empty_action
diff --git a/actionpack/test/controller/api/params_wrapper_test.rb b/actionpack/test/controller/api/params_wrapper_test.rb
index 53b3a0c3cc..814c24bfd8 100644
--- a/actionpack/test/controller/api/params_wrapper_test.rb
+++ b/actionpack/test/controller/api/params_wrapper_test.rb
@@ -1,4 +1,6 @@
-require 'abstract_unit'
+# frozen_string_literal: true
+
+require "abstract_unit"
 
 class ParamsWrapperForApiTest < ActionController::TestCase
   class UsersController < ActionController::API
@@ -17,10 +19,10 @@ class ParamsWrapperForApiTest < ActionController::TestCase
   tests UsersController
 
   def test_specify_wrapper_name
-    @request.env['CONTENT_TYPE'] = 'application/json'
-    post :test, params: { 'username' => 'sikachu' }
+    @request.env["CONTENT_TYPE"] = "application/json"
+    post :test, params: { "username" => "sikachu" }
 
-    expected = { 'username' => 'sikachu', 'person' => { 'username' => 'sikachu' }}
+    expected = { "username" => "sikachu", "person" => { "username" => "sikachu" } }
     assert_equal expected, @controller.last_parameters
   end
 end
diff --git a/actionpack/test/controller/api/redirect_to_test.rb b/actionpack/test/controller/api/redirect_to_test.rb
index 18877c4b3a..f8230dd6a9 100644
--- a/actionpack/test/controller/api/redirect_to_test.rb
+++ b/actionpack/test/controller/api/redirect_to_test.rb
@@ -1,4 +1,6 @@
-require 'abstract_unit'
+# frozen_string_literal: true
+
+require "abstract_unit"
 
 class RedirectToApiController < ActionController::API
   def one
diff --git a/actionpack/test/controller/api/renderers_test.rb b/actionpack/test/controller/api/renderers_test.rb
index 911a8144b2..e7a9a4b2da 100644
--- a/actionpack/test/controller/api/renderers_test.rb
+++ b/actionpack/test/controller/api/renderers_test.rb
@@ -1,14 +1,16 @@
-require 'abstract_unit'
-require 'active_support/core_ext/hash/conversions'
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "active_support/core_ext/hash/conversions"
 
 class RenderersApiController < ActionController::API
   class Model
     def to_json(options = {})
-      { a: 'b' }.to_json(options)
+      { a: "b" }.to_json(options)
     end
 
     def to_xml(options = {})
-      { a: 'b' }.to_xml(options)
+      { a: "b" }.to_xml(options)
     end
   end
 
@@ -21,11 +23,7 @@ class RenderersApiController < ActionController::API
   end
 
   def plain
-    render plain: 'Hi from plain', status: 500
-  end
-
-  def text
-    render text: 'Hi from text', status: 500
+    render plain: "Hi from plain", status: 500
   end
 end
 
@@ -35,26 +33,18 @@ class RenderersApiTest < ActionController::TestCase
   def test_render_json
     get :one
     assert_response :success
-    assert_equal({ a: 'b' }.to_json, @response.body)
+    assert_equal({ a: "b" }.to_json, @response.body)
   end
 
   def test_render_xml
     get :two
     assert_response :success
-    assert_equal({ a: 'b' }.to_xml, @response.body)
+    assert_equal({ a: "b" }.to_xml, @response.body)
   end
 
   def test_render_plain
     get :plain
     assert_response :internal_server_error
-    assert_equal('Hi from plain', @response.body)
-  end
-
-  def test_render_text
-    assert_deprecated do
-      get :text
-    end
-    assert_response :internal_server_error
-    assert_equal('Hi from text', @response.body)
+    assert_equal("Hi from plain", @response.body)
   end
 end
diff --git a/actionpack/test/controller/api/url_for_test.rb b/actionpack/test/controller/api/url_for_test.rb
index 0d8691a091..aa3428bc85 100644
--- a/actionpack/test/controller/api/url_for_test.rb
+++ b/actionpack/test/controller/api/url_for_test.rb
@@ -1,4 +1,6 @@
-require 'abstract_unit'
+# frozen_string_literal: true
+
+require "abstract_unit"
 
 class UrlForApiController < ActionController::API
   def one; end
@@ -10,7 +12,7 @@ class UrlForApiTest < ActionController::TestCase
 
   def setup
     super
-    @request.host = 'www.example.com'
+    @request.host = "www.example.com"
   end
 
   def test_url_for
diff --git a/actionpack/test/controller/api/with_cookies_test.rb b/actionpack/test/controller/api/with_cookies_test.rb
index 4491dc9002..1a6e12a4f3 100644
--- a/actionpack/test/controller/api/with_cookies_test.rb
+++ b/actionpack/test/controller/api/with_cookies_test.rb
@@ -1,4 +1,6 @@
-require 'abstract_unit'
+# frozen_string_literal: true
+
+require "abstract_unit"
 
 class WithCookiesController < ActionController::API
   include ActionController::Cookies
@@ -12,10 +14,10 @@ class WithCookiesTest < ActionController::TestCase
   tests WithCookiesController
 
   def test_with_cookies
-    request.cookies[:foobar] = 'bazbang'
+    request.cookies[:foobar] = "bazbang"
 
     get :with_cookies
 
-    assert_equal 'bazbang', response.body
+    assert_equal "bazbang", response.body
   end
 end
diff --git a/actionpack/test/controller/api/with_helpers_test.rb b/actionpack/test/controller/api/with_helpers_test.rb
new file mode 100644
index 0000000000..00179d3505
--- /dev/null
+++ b/actionpack/test/controller/api/with_helpers_test.rb
@@ -0,0 +1,44 @@
+# frozen_string_literal: true
+
+require "abstract_unit"
+
+module ApiWithHelper
+  def my_helper
+    "helper"
+  end
+end
+
+class WithHelpersController < ActionController::API
+  include ActionController::Helpers
+  helper ApiWithHelper
+
+  def with_helpers
+    render plain: self.class.helpers.my_helper
+  end
+end
+
+class SubclassWithHelpersController < WithHelpersController
+  def with_helpers
+    render plain: self.class.helpers.my_helper
+  end
+end
+
+class WithHelpersTest < ActionController::TestCase
+  tests WithHelpersController
+
+  def test_with_helpers
+    get :with_helpers
+
+    assert_equal "helper", response.body
+  end
+end
+
+class SubclassWithHelpersTest < ActionController::TestCase
+  tests WithHelpersController
+
+  def test_with_helpers
+    get :with_helpers
+
+    assert_equal "helper", response.body
+  end
+end
diff --git a/actionpack/test/controller/base_test.rb b/actionpack/test/controller/base_test.rb
index 577a3d5800..9ac82c0d65 100644
--- a/actionpack/test/controller/base_test.rb
+++ b/actionpack/test/controller/base_test.rb
@@ -1,6 +1,8 @@
-require 'abstract_unit'
-require 'active_support/logger'
-require 'controller/fake_models'
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "active_support/logger"
+require "controller/fake_models"
 
 # Provide some controller to run the tests on.
 module Submodule
@@ -11,6 +13,12 @@ end
 class EmptyController < ActionController::Base
 end
 
+class SimpleController < ActionController::Base
+  def hello
+    self.response_body = "hello"
+  end
+end
+
 class NonEmptyController < ActionController::Base
   def public_action
     head :ok
@@ -19,11 +27,11 @@ end
 
 class DefaultUrlOptionsController < ActionController::Base
   def from_view
-    render :inline => "<%= #{params[:route]} %>"
+    render inline: "<%= #{params[:route]} %>"
   end
 
   def default_url_options
-    { :host => 'www.override.com', :action => 'new', :locale => 'en' }
+    { host: "www.override.com", action: "new", locale: "en" }
   end
 end
 
@@ -33,17 +41,17 @@ class OptionalDefaultUrlOptionsController < ActionController::Base
   end
 
   def default_url_options
-    { format: 'atom', id: 'default-id' }
+    { format: "atom", id: "default-id" }
   end
 end
 
 class UrlOptionsController < ActionController::Base
   def from_view
-    render :inline => "<%= #{params[:route]} %>"
+    render inline: "<%= #{params[:route]} %>"
   end
 
   def url_options
-    super.merge(:host => 'www.override.com')
+    super.merge(host: "www.override.com")
   end
 end
 
@@ -58,17 +66,16 @@ class ActionMissingController < ActionController::Base
 end
 
 class ControllerClassTests < ActiveSupport::TestCase
-
   def test_controller_path
-    assert_equal 'empty', EmptyController.controller_path
+    assert_equal "empty", EmptyController.controller_path
     assert_equal EmptyController.controller_path, EmptyController.new.controller_path
-    assert_equal 'submodule/contained_empty', Submodule::ContainedEmptyController.controller_path
+    assert_equal "submodule/contained_empty", Submodule::ContainedEmptyController.controller_path
     assert_equal Submodule::ContainedEmptyController.controller_path, Submodule::ContainedEmptyController.new.controller_path
   end
 
   def test_controller_name
-    assert_equal 'empty', EmptyController.controller_name
-    assert_equal 'contained_empty', Submodule::ContainedEmptyController.controller_name
+    assert_equal "empty", EmptyController.controller_name
+    assert_equal "contained_empty", Submodule::ContainedEmptyController.controller_name
   end
 
   def test_no_deprecation_when_action_view_record_identifier_is_included
@@ -80,13 +87,13 @@ class ControllerClassTests < ActiveSupport::TestCase
       dom_id = RecordIdentifierIncludedController.new.dom_id(record)
     end
 
-    assert_equal 'comment_1', dom_id
+    assert_equal "comment_1", dom_id
 
     dom_class = nil
     assert_not_deprecated do
       dom_class = RecordIdentifierIncludedController.new.dom_class(record)
     end
-    assert_equal 'comment', dom_class
+    assert_equal "comment", dom_class
   end
 end
 
@@ -112,13 +119,34 @@ class ControllerInstanceTests < ActiveSupport::TestCase
   end
 
   def test_temporary_anonymous_controllers
-    name = 'ExamplesController'
+    name = "ExamplesController"
     klass = Class.new(ActionController::Base)
     Object.const_set(name, klass)
 
     controller = klass.new
     assert_equal "examples", controller.controller_path
   end
+
+  def test_response_has_default_headers
+    original_default_headers = ActionDispatch::Response.default_headers
+
+    ActionDispatch::Response.default_headers = {
+      "X-Frame-Options" => "DENY",
+      "X-Content-Type-Options" => "nosniff",
+      "X-XSS-Protection" => "1;"
+    }
+
+    response_headers = SimpleController.action("hello").call(
+      "REQUEST_METHOD" => "GET",
+      "rack.input" => -> {}
+    )[1]
+
+    assert response_headers.key?("X-Frame-Options")
+    assert response_headers.key?("X-Content-Type-Options")
+    assert response_headers.key?("X-XSS-Protection")
+  ensure
+    ActionDispatch::Response.default_headers = original_default_headers
+  end
 end
 
 class PerformActionTest < ActionController::TestCase
@@ -152,40 +180,40 @@ class UrlOptionsTest < ActionController::TestCase
 
   def setup
     super
-    @request.host = 'www.example.com'
+    @request.host = "www.example.com"
   end
 
   def test_url_for_query_params_included
     rs = ActionDispatch::Routing::RouteSet.new
     rs.draw do
-      get 'home' => 'pages#home'
+      get "home" => "pages#home"
     end
 
     options = {
-      :action     => "home",
-      :controller => "pages",
-      :only_path  => true,
-      :params     => { "token" => "secret" }
+      action: "home",
+      controller: "pages",
+      only_path: true,
+      params: { "token" => "secret" }
     }
 
-    assert_equal '/home?token=secret', rs.url_for(options)
+    assert_equal "/home?token=secret", rs.url_for(options)
   end
 
   def test_url_options_override
     with_routing do |set|
       set.draw do
-        get 'from_view', :to => 'url_options#from_view', :as => :from_view
+        get "from_view", to: "url_options#from_view", as: :from_view
 
         ActiveSupport::Deprecation.silence do
-          get ':controller/:action'
+          get ":controller/:action"
         end
       end
 
       get :from_view, params: { route: "from_view_url" }
 
-      assert_equal 'http://www.override.com/from_view', @response.body
-      assert_equal 'http://www.override.com/from_view', @controller.send(:from_view_url)
-      assert_equal 'http://www.override.com/default_url_options/index', @controller.url_for(:controller => 'default_url_options')
+      assert_equal "http://www.override.com/from_view", @response.body
+      assert_equal "http://www.override.com/from_view", @controller.send(:from_view_url)
+      assert_equal "http://www.override.com/default_url_options/index", @controller.url_for(controller: "default_url_options")
     end
   end
 
@@ -195,7 +223,7 @@ class UrlOptionsTest < ActionController::TestCase
         get "account/overview"
       end
 
-      assert !@controller.class.action_methods.include?("account_overview_path")
+      assert_not_includes @controller.class.action_methods, "account_overview_path"
     end
   end
 end
@@ -205,24 +233,24 @@ class DefaultUrlOptionsTest < ActionController::TestCase
 
   def setup
     super
-    @request.host = 'www.example.com'
+    @request.host = "www.example.com"
   end
 
   def test_default_url_options_override
     with_routing do |set|
       set.draw do
-        get 'from_view', :to => 'default_url_options#from_view', :as => :from_view
+        get "from_view", to: "default_url_options#from_view", as: :from_view
 
         ActiveSupport::Deprecation.silence do
-          get ':controller/:action'
+          get ":controller/:action"
         end
       end
 
       get :from_view, params: { route: "from_view_url" }
 
-      assert_equal 'http://www.override.com/from_view?locale=en', @response.body
-      assert_equal 'http://www.override.com/from_view?locale=en', @controller.send(:from_view_url)
-      assert_equal 'http://www.override.com/default_url_options/new?locale=en', @controller.url_for(:controller => 'default_url_options')
+      assert_equal "http://www.override.com/from_view?locale=en", @response.body
+      assert_equal "http://www.override.com/from_view?locale=en", @controller.send(:from_view_url)
+      assert_equal "http://www.override.com/default_url_options/new?locale=en", @controller.url_for(controller: "default_url_options")
     end
   end
 
@@ -234,23 +262,23 @@ class DefaultUrlOptionsTest < ActionController::TestCase
         end
 
         ActiveSupport::Deprecation.silence do
-          get ':controller/:action'
+          get ":controller/:action"
         end
       end
 
       get :from_view, params: { route: "description_path(1)" }
 
-      assert_equal '/en/descriptions/1', @response.body
-      assert_equal '/en/descriptions', @controller.send(:descriptions_path)
-      assert_equal '/pl/descriptions', @controller.send(:descriptions_path, "pl")
-      assert_equal '/pl/descriptions', @controller.send(:descriptions_path, :locale => "pl")
-      assert_equal '/pl/descriptions.xml', @controller.send(:descriptions_path, "pl", "xml")
-      assert_equal '/en/descriptions.xml', @controller.send(:descriptions_path, :format => "xml")
-      assert_equal '/en/descriptions/1', @controller.send(:description_path, 1)
-      assert_equal '/pl/descriptions/1', @controller.send(:description_path, "pl", 1)
-      assert_equal '/pl/descriptions/1', @controller.send(:description_path, 1, :locale => "pl")
-      assert_equal '/pl/descriptions/1.xml', @controller.send(:description_path, "pl", 1, "xml")
-      assert_equal '/en/descriptions/1.xml', @controller.send(:description_path, 1, :format => "xml")
+      assert_equal "/en/descriptions/1", @response.body
+      assert_equal "/en/descriptions", @controller.send(:descriptions_path)
+      assert_equal "/pl/descriptions", @controller.send(:descriptions_path, "pl")
+      assert_equal "/pl/descriptions", @controller.send(:descriptions_path, locale: "pl")
+      assert_equal "/pl/descriptions.xml", @controller.send(:descriptions_path, "pl", "xml")
+      assert_equal "/en/descriptions.xml", @controller.send(:descriptions_path, format: "xml")
+      assert_equal "/en/descriptions/1", @controller.send(:description_path, 1)
+      assert_equal "/pl/descriptions/1", @controller.send(:description_path, "pl", 1)
+      assert_equal "/pl/descriptions/1", @controller.send(:description_path, 1, locale: "pl")
+      assert_equal "/pl/descriptions/1.xml", @controller.send(:description_path, "pl", 1, "xml")
+      assert_equal "/en/descriptions/1.xml", @controller.send(:description_path, 1, format: "xml")
     end
   end
 end
@@ -259,10 +287,10 @@ class OptionalDefaultUrlOptionsControllerTest < ActionController::TestCase
   def test_default_url_options_override_missing_positional_arguments
     with_routing do |set|
       set.draw do
-        get "/things/:id(.:format)" => 'things#show', :as => :thing
+        get "/things/:id(.:format)" => "things#show", :as => :thing
       end
-      assert_equal '/things/1.atom', thing_path('1')
-      assert_equal '/things/default-id.atom', thing_path
+      assert_equal "/things/1.atom", thing_path("1")
+      assert_equal "/things/default-id.atom", thing_path
     end
   end
 end
@@ -272,7 +300,7 @@ class EmptyUrlOptionsTest < ActionController::TestCase
 
   def setup
     super
-    @request.host = 'www.example.com'
+    @request.host = "www.example.com"
   end
 
   def test_ensure_url_for_works_as_expected_when_called_with_no_options_if_default_url_options_is_not_set
@@ -289,7 +317,7 @@ class EmptyUrlOptionsTest < ActionController::TestCase
         resources :things
       end
 
-      assert_equal '/things', @controller.send(:things_path)
+      assert_equal "/things", @controller.send(:things_path)
     end
   end
 end
diff --git a/actionpack/test/controller/caching_test.rb b/actionpack/test/controller/caching_test.rb
index 7faf3cd8c6..3557f9f888 100644
--- a/actionpack/test/controller/caching_test.rb
+++ b/actionpack/test/controller/caching_test.rb
@@ -1,10 +1,12 @@
-require 'fileutils'
-require 'abstract_unit'
-require 'lib/controller/fake_models'
+# frozen_string_literal: true
 
-CACHE_DIR = 'test_cache'
+require "fileutils"
+require "abstract_unit"
+require "lib/controller/fake_models"
+
+CACHE_DIR = "test_cache"
 # Don't change '/../temp/' cavalierly or you might hose something you don't want hosed
-FILE_STORE_PATH = File.join(File.dirname(__FILE__), '/../temp/', CACHE_DIR)
+FILE_STORE_PATH = File.join(__dir__, "../temp/", CACHE_DIR)
 
 class FragmentCachingMetalTestController < ActionController::Metal
   abstract!
@@ -21,15 +23,11 @@ class FragmentCachingMetalTest < ActionController::TestCase
     @controller = FragmentCachingMetalTestController.new
     @controller.perform_caching = true
     @controller.cache_store = @store
-    @params = { controller: 'posts', action: 'index' }
+    @params = { controller: "posts", action: "index" }
     @controller.params = @params
     @controller.request = @request
     @controller.response = @response
   end
-
-  def test_fragment_cache_key
-    assert_equal 'views/what a key', @controller.fragment_cache_key('what a key')
-  end
 end
 
 class CachingController < ActionController::Base
@@ -43,102 +41,123 @@ class FragmentCachingTestController < CachingController
 end
 
 class FragmentCachingTest < ActionController::TestCase
+  ModelWithKeyAndVersion = Struct.new(:cache_key, :cache_version)
+
   def setup
     super
     @store = ActiveSupport::Cache::MemoryStore.new
     @controller = FragmentCachingTestController.new
     @controller.perform_caching = true
     @controller.cache_store = @store
-    @params = {:controller => 'posts', :action => 'index'}
+    @params = { controller: "posts", action: "index" }
     @controller.params = @params
     @controller.request = @request
     @controller.response = @response
+
+    @m1v1 = ModelWithKeyAndVersion.new("model/1", "1")
+    @m1v2 = ModelWithKeyAndVersion.new("model/1", "2")
+    @m2v1 = ModelWithKeyAndVersion.new("model/2", "1")
+    @m2v2 = ModelWithKeyAndVersion.new("model/2", "2")
   end
 
   def test_fragment_cache_key
-    assert_equal 'views/what a key', @controller.fragment_cache_key('what a key')
-    assert_equal "views/test.host/fragment_caching_test/some_action",
-                  @controller.fragment_cache_key(:controller => 'fragment_caching_test',:action => 'some_action')
+    assert_deprecated do
+      assert_equal "views/what a key", @controller.fragment_cache_key("what a key")
+      assert_equal "views/test.host/fragment_caching_test/some_action",
+        @controller.fragment_cache_key(controller: "fragment_caching_test", action: "some_action")
+    end
+  end
+
+  def test_combined_fragment_cache_key
+    assert_equal [ :views, "what a key" ], @controller.combined_fragment_cache_key("what a key")
+    assert_equal [ :views, "test.host/fragment_caching_test/some_action" ],
+      @controller.combined_fragment_cache_key(controller: "fragment_caching_test", action: "some_action")
   end
 
   def test_read_fragment_with_caching_enabled
-    @store.write('views/name', 'value')
-    assert_equal 'value', @controller.read_fragment('name')
+    @store.write("views/name", "value")
+    assert_equal "value", @controller.read_fragment("name")
   end
 
   def test_read_fragment_with_caching_disabled
     @controller.perform_caching = false
-    @store.write('views/name', 'value')
-    assert_nil @controller.read_fragment('name')
+    @store.write("views/name", "value")
+    assert_nil @controller.read_fragment("name")
+  end
+
+  def test_read_fragment_with_versioned_model
+    @controller.write_fragment([ "stuff", @m1v1 ], "hello")
+    assert_equal "hello", @controller.read_fragment([ "stuff", @m1v1 ])
+    assert_nil @controller.read_fragment([ "stuff", @m1v2 ])
   end
 
   def test_fragment_exist_with_caching_enabled
-    @store.write('views/name', 'value')
-    assert @controller.fragment_exist?('name')
-    assert !@controller.fragment_exist?('other_name')
+    @store.write("views/name", "value")
+    assert @controller.fragment_exist?("name")
+    assert !@controller.fragment_exist?("other_name")
   end
 
   def test_fragment_exist_with_caching_disabled
     @controller.perform_caching = false
-    @store.write('views/name', 'value')
-    assert !@controller.fragment_exist?('name')
-    assert !@controller.fragment_exist?('other_name')
+    @store.write("views/name", "value")
+    assert !@controller.fragment_exist?("name")
+    assert !@controller.fragment_exist?("other_name")
   end
 
   def test_write_fragment_with_caching_enabled
-    assert_nil @store.read('views/name')
-    assert_equal 'value', @controller.write_fragment('name', 'value')
-    assert_equal 'value', @store.read('views/name')
+    assert_nil @store.read("views/name")
+    assert_equal "value", @controller.write_fragment("name", "value")
+    assert_equal "value", @store.read("views/name")
   end
 
   def test_write_fragment_with_caching_disabled
-    assert_nil @store.read('views/name')
+    assert_nil @store.read("views/name")
     @controller.perform_caching = false
-    assert_equal 'value', @controller.write_fragment('name', 'value')
-    assert_nil @store.read('views/name')
+    assert_equal "value", @controller.write_fragment("name", "value")
+    assert_nil @store.read("views/name")
   end
 
   def test_expire_fragment_with_simple_key
-    @store.write('views/name', 'value')
-    @controller.expire_fragment 'name'
-    assert_nil @store.read('views/name')
+    @store.write("views/name", "value")
+    @controller.expire_fragment "name"
+    assert_nil @store.read("views/name")
   end
 
   def test_expire_fragment_with_regexp
-    @store.write('views/name', 'value')
-    @store.write('views/another_name', 'another_value')
-    @store.write('views/primalgrasp', 'will not expire ;-)')
+    @store.write("views/name", "value")
+    @store.write("views/another_name", "another_value")
+    @store.write("views/primalgrasp", "will not expire ;-)")
 
     @controller.expire_fragment(/name/)
 
-    assert_nil @store.read('views/name')
-    assert_nil @store.read('views/another_name')
-    assert_equal 'will not expire ;-)', @store.read('views/primalgrasp')
+    assert_nil @store.read("views/name")
+    assert_nil @store.read("views/another_name")
+    assert_equal "will not expire ;-)", @store.read("views/primalgrasp")
   end
 
   def test_fragment_for
-    @store.write('views/expensive', 'fragment content')
+    @store.write("views/expensive", "fragment content")
     fragment_computed = false
 
     view_context = @controller.view_context
 
-    buffer = 'generated till now -> '.html_safe
-    buffer << view_context.send(:fragment_for, 'expensive') { fragment_computed = true }
+    buffer = "generated till now -> ".html_safe
+    buffer << view_context.send(:fragment_for, "expensive") { fragment_computed = true }
 
     assert !fragment_computed
-    assert_equal 'generated till now -> fragment content', buffer
+    assert_equal "generated till now -> fragment content", buffer
   end
 
   def test_html_safety
-    assert_nil @store.read('views/name')
-    content = 'value'.html_safe
-    assert_equal content, @controller.write_fragment('name', content)
+    assert_nil @store.read("views/name")
+    content = "value".html_safe
+    assert_equal content, @controller.write_fragment("name", content)
 
-    cached = @store.read('views/name')
+    cached = @store.read("views/name")
     assert_equal content, cached
     assert_equal String, cached.class
 
-    html_safe = @controller.read_fragment('name')
+    html_safe = @controller.read_fragment("name")
     assert_equal content, html_safe
     assert html_safe.html_safe?
   end
@@ -184,6 +203,7 @@ class FunctionalFragmentCachingTest < ActionController::TestCase
     @controller = FunctionalCachingController.new
     @controller.perform_caching = true
     @controller.cache_store = @store
+    @controller.enable_fragment_cache_logging = true
   end
 
   def test_fragment_caching
@@ -197,7 +217,7 @@ CACHED
     assert_equal expected_body, @response.body
 
     assert_equal "This bit's fragment cached",
-      @store.read("views/test.host/functional_caching/fragment_cached/#{template_digest("functional_caching/fragment_cached")}")
+      @store.read("views/functional_caching/fragment_cached:#{template_digest("functional_caching/fragment_cached")}/fragment")
   end
 
   def test_fragment_caching_in_partials
@@ -206,7 +226,7 @@ CACHED
     assert_match(/Old fragment caching in a partial/, @response.body)
 
     assert_match("Old fragment caching in a partial",
-      @store.read("views/test.host/functional_caching/html_fragment_cached_with_partial/#{template_digest("functional_caching/_partial")}"))
+      @store.read("views/functional_caching/_partial:#{template_digest("functional_caching/_partial")}/test.host/functional_caching/html_fragment_cached_with_partial"))
   end
 
   def test_skipping_fragment_cache_digesting
@@ -236,7 +256,7 @@ CACHED
     assert_match(/Some inline content/, @response.body)
     assert_match(/Some cached content/, @response.body)
     assert_match("Some cached content",
-      @store.read("views/test.host/functional_caching/inline_fragment_cached/#{template_digest("functional_caching/inline_fragment_cached")}"))
+      @store.read("views/functional_caching/inline_fragment_cached:#{template_digest("functional_caching/inline_fragment_cached")}/test.host/functional_caching/inline_fragment_cached"))
   end
 
   def test_fragment_cache_instrumentation
@@ -263,7 +283,7 @@ CACHED
     assert_equal expected_body, @response.body
 
     assert_equal "<p>ERB</p>",
-      @store.read("views/test.host/functional_caching/formatted_fragment_cached/#{template_digest("functional_caching/formatted_fragment_cached")}")
+      @store.read("views/functional_caching/formatted_fragment_cached:#{template_digest("functional_caching/formatted_fragment_cached")}/fragment")
   end
 
   def test_xml_formatted_fragment_caching
@@ -274,10 +294,9 @@ CACHED
     assert_equal expected_body, @response.body
 
     assert_equal "  <p>Builder</p>\n",
-      @store.read("views/test.host/functional_caching/formatted_fragment_cached/#{template_digest("functional_caching/formatted_fragment_cached")}")
+      @store.read("views/functional_caching/formatted_fragment_cached:#{template_digest("functional_caching/formatted_fragment_cached")}/fragment")
   end
 
-
   def test_fragment_caching_with_variant
     get :formatted_fragment_cached_with_variant, format: "html", params: { v: :phone }
     assert_response :success
@@ -286,7 +305,7 @@ CACHED
     assert_equal expected_body, @response.body
 
     assert_equal "<p>PHONE</p>",
-      @store.read("views/test.host/functional_caching/formatted_fragment_cached_with_variant/#{template_digest("functional_caching/formatted_fragment_cached_with_variant")}")
+      @store.read("views/functional_caching/formatted_fragment_cached_with_variant:#{template_digest("functional_caching/formatted_fragment_cached_with_variant")}/fragment")
   end
 
   private
@@ -296,10 +315,9 @@ CACHED
 end
 
 class CacheHelperOutputBufferTest < ActionController::TestCase
-
   class MockController
     def read_fragment(name, options)
-      return false
+      false
     end
 
     def write_fragment(name, fragment, options)
@@ -315,9 +333,9 @@ class CacheHelperOutputBufferTest < ActionController::TestCase
     output_buffer = ActionView::OutputBuffer.new
     controller = MockController.new
     cache_helper = Class.new do
-      def self.controller; end;
-      def self.output_buffer; end;
-      def self.output_buffer=; end;
+      def self.controller; end
+      def self.output_buffer; end
+      def self.output_buffer=; end
     end
     cache_helper.extend(ActionView::Helpers::CacheHelper)
 
@@ -325,7 +343,7 @@ class CacheHelperOutputBufferTest < ActionController::TestCase
       cache_helper.stub :output_buffer, output_buffer do
         assert_called_with cache_helper, :output_buffer=, [output_buffer.class.new(output_buffer)] do
           assert_nothing_raised do
-            cache_helper.send :fragment_for, 'Test fragment name', 'Test fragment', &Proc.new{ nil }
+            cache_helper.send :fragment_for, "Test fragment name", "Test fragment", &Proc.new { nil }
           end
         end
       end
@@ -336,9 +354,9 @@ class CacheHelperOutputBufferTest < ActionController::TestCase
     output_buffer = ActiveSupport::SafeBuffer.new
     controller = MockController.new
     cache_helper = Class.new do
-      def self.controller; end;
-      def self.output_buffer; end;
-      def self.output_buffer=; end;
+      def self.controller; end
+      def self.output_buffer; end
+      def self.output_buffer=; end
     end
     cache_helper.extend(ActionView::Helpers::CacheHelper)
 
@@ -346,7 +364,7 @@ class CacheHelperOutputBufferTest < ActionController::TestCase
       cache_helper.stub :output_buffer, output_buffer do
         assert_called_with cache_helper, :output_buffer=, [output_buffer.class.new(output_buffer)] do
           assert_nothing_raised do
-            cache_helper.send :fragment_for, 'Test fragment name', 'Test fragment', &Proc.new{ nil }
+            cache_helper.send :fragment_for, "Test fragment name", "Test fragment", &Proc.new { nil }
           end
         end
       end
@@ -376,26 +394,31 @@ class CollectionCacheController < ActionController::Base
   attr_accessor :partial_rendered_times
 
   def index
-    @customers = [Customer.new('david', params[:id] || 1)]
+    @customers = [Customer.new("david", params[:id] || 1)]
   end
 
   def index_ordered
-    @customers = [Customer.new('david', 1), Customer.new('david', 2), Customer.new('david', 3)]
-    render 'index'
+    @customers = [Customer.new("david", 1), Customer.new("david", 2), Customer.new("david", 3)]
+    render "index"
   end
 
   def index_explicit_render_in_controller
-    @customers = [Customer.new('david', 1)]
-    render partial: 'customers/customer', collection: @customers, cached: true
+    @customers = [Customer.new("david", 1)]
+    render partial: "customers/customer", collection: @customers, cached: true
   end
 
   def index_with_comment
-    @customers = [Customer.new('david', 1)]
-    render partial: 'customers/commented_customer', collection: @customers, as: :customer, cached: true
+    @customers = [Customer.new("david", 1)]
+    render partial: "customers/commented_customer", collection: @customers, as: :customer, cached: true
+  end
+
+  def index_with_callable_cache_key
+    @customers = [Customer.new("david", 1)]
+    render partial: "customers/customer", collection: @customers, cached: -> customer { "cached_david" }
   end
 end
 
-class AutomaticCollectionCacheTest < ActionController::TestCase
+class CollectionCacheTest < ActionController::TestCase
   def setup
     super
     @controller = CollectionCacheController.new
@@ -408,7 +431,7 @@ class AutomaticCollectionCacheTest < ActionController::TestCase
   def test_collection_fetches_cached_views
     get :index
     assert_equal 1, @controller.partial_rendered_times
-    assert_customer_cached 'david/1', 'david, 1'
+    assert_match "david, 1", ActionView::PartialRenderer.collection_cache.read("views/customers/_customer:7c228ab609f0baf0b1f2367469210937/david/1")
 
     get :index
     assert_equal 1, @controller.partial_rendered_times
@@ -417,17 +440,17 @@ class AutomaticCollectionCacheTest < ActionController::TestCase
   def test_preserves_order_when_reading_from_cache_plus_rendering
     get :index, params: { id: 2 }
     assert_equal 1, @controller.partial_rendered_times
-    assert_select ':root', 'david, 2'
+    assert_select ":root", "david, 2"
 
     get :index_ordered
     assert_equal 3, @controller.partial_rendered_times
-    assert_select ':root', "david, 1\n  david, 2\n  david, 3"
+    assert_select ":root", "david, 1\n  david, 2\n  david, 3"
   end
 
   def test_explicit_render_call_with_options
     get :index_explicit_render_in_controller
 
-    assert_select ':root', "david, 1"
+    assert_select ":root", "david, 1"
   end
 
   def test_caching_works_with_beginning_comment
@@ -438,11 +461,10 @@ class AutomaticCollectionCacheTest < ActionController::TestCase
     assert_equal 1, @controller.partial_rendered_times
   end
 
-  private
-    def assert_customer_cached(key, content)
-      assert_match content,
-        ActionView::PartialRenderer.collection_cache.read("views/#{key}/7c228ab609f0baf0b1f2367469210937")
-    end
+  def test_caching_with_callable_cache_key
+    get :index_with_callable_cache_key
+    assert_match "david, 1", ActionView::PartialRenderer.collection_cache.read("views/customers/_customer:7c228ab609f0baf0b1f2367469210937/cached_david")
+  end
 end
 
 class FragmentCacheKeyTestController < CachingController
@@ -461,11 +483,21 @@ class FragmentCacheKeyTest < ActionController::TestCase
     @controller.cache_store = @store
   end
 
-  def test_fragment_cache_key
+  def test_combined_fragment_cache_key
     @controller.account_id = "123"
-    assert_equal 'views/v1/123/what a key', @controller.fragment_cache_key('what a key')
+    assert_equal [ :views, "v1", "123", "what a key" ], @controller.combined_fragment_cache_key("what a key")
 
     @controller.account_id = nil
-    assert_equal 'views/v1//what a key', @controller.fragment_cache_key('what a key')
+    assert_equal [ :views, "v1", "what a key" ], @controller.combined_fragment_cache_key("what a key")
+  end
+
+  def test_combined_fragment_cache_key_with_envs
+    ENV["RAILS_APP_VERSION"] = "55"
+    assert_equal [ :views, "55", "v1", "what a key" ], @controller.combined_fragment_cache_key("what a key")
+
+    ENV["RAILS_CACHE_ID"] = "66"
+    assert_equal [ :views, "66", "v1", "what a key" ], @controller.combined_fragment_cache_key("what a key")
+  ensure
+    ENV["RAILS_CACHE_ID"] = ENV["RAILS_APP_VERSION"] = nil
   end
 end
diff --git a/actionpack/test/controller/content_type_test.rb b/actionpack/test/controller/content_type_test.rb
index c02607b55e..636b025f2c 100644
--- a/actionpack/test/controller/content_type_test.rb
+++ b/actionpack/test/controller/content_type_test.rb
@@ -1,4 +1,6 @@
-require 'abstract_unit'
+# frozen_string_literal: true
+
+require "abstract_unit"
 
 class OldContentTypeController < ActionController::Base
   # :ported:
@@ -14,7 +16,7 @@ class OldContentTypeController < ActionController::Base
 
   # :ported:
   def render_content_type_from_render
-    render body: "hello world!", :content_type => Mime[:rss]
+    render body: "hello world!", content_type: Mime[:rss]
   end
 
   # :ported:
@@ -37,7 +39,7 @@ class OldContentTypeController < ActionController::Base
 
   def render_change_for_builder
     response.content_type = Mime[:html]
-    render :action => "render_default_for_builder"
+    render action: "render_default_for_builder"
   end
 
   def render_default_content_types_for_respond_to
@@ -131,13 +133,13 @@ class ContentTypeTest < ActionController::TestCase
 
   private
 
-  def with_default_charset(charset)
-    old_default_charset = ActionDispatch::Response.default_charset
-    ActionDispatch::Response.default_charset = charset
-    yield
-  ensure
-    ActionDispatch::Response.default_charset = old_default_charset
-  end
+    def with_default_charset(charset)
+      old_default_charset = ActionDispatch::Response.default_charset
+      ActionDispatch::Response.default_charset = charset
+      yield
+    ensure
+      ActionDispatch::Response.default_charset = old_default_charset
+    end
 end
 
 class AcceptBasedContentTypeTest < ActionController::TestCase
diff --git a/actionpack/test/controller/default_url_options_with_before_action_test.rb b/actionpack/test/controller/default_url_options_with_before_action_test.rb
index 12fbe0424e..fc5b8288cd 100644
--- a/actionpack/test/controller/default_url_options_with_before_action_test.rb
+++ b/actionpack/test/controller/default_url_options_with_before_action_test.rb
@@ -1,7 +1,8 @@
-require 'abstract_unit'
+# frozen_string_literal: true
 
-class ControllerWithBeforeActionAndDefaultUrlOptions < ActionController::Base
+require "abstract_unit"
 
+class ControllerWithBeforeActionAndDefaultUrlOptions < ActionController::Base
   before_action { I18n.locale = params[:locale] }
   after_action { I18n.locale = "en" }
 
@@ -10,16 +11,15 @@ class ControllerWithBeforeActionAndDefaultUrlOptions < ActionController::Base
   end
 
   def redirect
-    redirect_to :action => "target"
+    redirect_to action: "target"
   end
 
   def default_url_options
-    {:locale => "de"}
+    { locale: "de" }
   end
 end
 
 class ControllerWithBeforeActionAndDefaultUrlOptionsTest < ActionController::TestCase
-
   # This test has its roots in issue #1872
   test "should redirect with correct locale :de" do
     get :redirect, params: { locale: "de" }
diff --git a/actionpack/test/controller/filters_test.rb b/actionpack/test/controller/filters_test.rb
index 08271012e9..9f0a9dec7a 100644
--- a/actionpack/test/controller/filters_test.rb
+++ b/actionpack/test/controller/filters_test.rb
@@ -1,8 +1,10 @@
-require 'abstract_unit'
+# frozen_string_literal: true
+
+require "abstract_unit"
 
 class ActionController::Base
   class << self
-    %w(append_around_action prepend_after_action prepend_around_action prepend_before_action skip_after_action skip_before_action skip_action_callback).each do |pending|
+    %w(append_around_action prepend_after_action prepend_around_action prepend_before_action skip_after_action skip_before_action).each do |pending|
       define_method(pending) do |*args|
         $stderr.puts "#{pending} unimplemented: #{args.inspect}"
       end unless method_defined?(pending)
@@ -21,7 +23,7 @@ class FilterTest < ActionController::TestCase
     after_action  :clean_up
 
     def show
-      render :inline => "ran action"
+      render inline: "ran action"
     end
 
     private
@@ -37,7 +39,7 @@ class FilterTest < ActionController::TestCase
   end
 
   class ChangingTheRequirementsController < TestController
-    before_action :ensure_login, :except => [:go_wild]
+    before_action :ensure_login, except: [:go_wild]
 
     def go_wild
       render plain: "gobble"
@@ -55,15 +57,15 @@ class FilterTest < ActionController::TestCase
       end
     end
 
-    protected
-    (1..3).each do |i|
-      define_method "try_#{i}" do
-        instance_variable_set :@try, i
-        if action_name == "fail_#{i}"
-          head(404)
+    private
+      (1..3).each do |i|
+        define_method "try_#{i}" do
+          instance_variable_set :@try, i
+          if action_name == "fail_#{i}"
+            head(404)
+          end
         end
       end
-    end
   end
 
   class RenderingController < ActionController::Base
@@ -72,14 +74,14 @@ class FilterTest < ActionController::TestCase
 
     def show
       @ran_action = true
-      render :inline => "ran action"
+      render inline: "ran action"
     end
 
     private
       def before_action_rendering
         @ran_filter ||= []
         @ran_filter << "before_action_rendering"
-        render :inline => "something else"
+        render inline: "something else"
       end
 
       def unreached_after_action
@@ -102,19 +104,19 @@ class FilterTest < ActionController::TestCase
 
     def show
       @ran_action = true
-      render :inline => "ran show action"
+      render inline: "ran show action"
     end
 
     def target_of_redirection
       @ran_target_of_redirection = true
-      render :inline => "ran target_of_redirection action"
+      render inline: "ran target_of_redirection action"
     end
 
     private
       def before_action_redirects
         @ran_filter ||= []
         @ran_filter << "before_action_redirects"
-        redirect_to(:action => 'target_of_redirection')
+        redirect_to(action: "target_of_redirection")
       end
 
       def unreached_after_action
@@ -133,15 +135,15 @@ class FilterTest < ActionController::TestCase
 
   class ConditionalFilterController < ActionController::Base
     def show
-      render :inline => "ran action"
+      render inline: "ran action"
     end
 
     def another_action
-      render :inline => "ran action"
+      render inline: "ran action"
     end
 
     def show_without_action
-      render :inline => "ran action without action"
+      render inline: "ran action without action"
     end
 
     private
@@ -157,28 +159,28 @@ class FilterTest < ActionController::TestCase
   end
 
   class ConditionalCollectionFilterController < ConditionalFilterController
-    before_action :ensure_login, :except => [ :show_without_action, :another_action ]
+    before_action :ensure_login, except: [ :show_without_action, :another_action ]
   end
 
   class OnlyConditionSymController < ConditionalFilterController
-    before_action :ensure_login, :only => :show
+    before_action :ensure_login, only: :show
   end
 
   class ExceptConditionSymController < ConditionalFilterController
-    before_action :ensure_login, :except => :show_without_action
+    before_action :ensure_login, except: :show_without_action
   end
 
   class BeforeAndAfterConditionController < ConditionalFilterController
-    before_action :ensure_login, :only => :show
-    after_action  :clean_up_tmp, :only => :show
+    before_action :ensure_login, only: :show
+    after_action  :clean_up_tmp, only: :show
   end
 
   class OnlyConditionProcController < ConditionalFilterController
-    before_action(:only => :show) {|c| c.instance_variable_set(:"@ran_proc_action", true) }
+    before_action(only: :show) { |c| c.instance_variable_set(:"@ran_proc_action", true) }
   end
 
   class ExceptConditionProcController < ConditionalFilterController
-    before_action(:except => :show_without_action) {|c| c.instance_variable_set(:"@ran_proc_action", true) }
+    before_action(except: :show_without_action) { |c| c.instance_variable_set(:"@ran_proc_action", true) }
   end
 
   class ConditionalClassFilter
@@ -186,24 +188,24 @@ class FilterTest < ActionController::TestCase
   end
 
   class OnlyConditionClassController < ConditionalFilterController
-    before_action ConditionalClassFilter, :only => :show
+    before_action ConditionalClassFilter, only: :show
   end
 
   class ExceptConditionClassController < ConditionalFilterController
-    before_action ConditionalClassFilter, :except => :show_without_action
+    before_action ConditionalClassFilter, except: :show_without_action
   end
 
   class AnomolousYetValidConditionController < ConditionalFilterController
-    before_action(ConditionalClassFilter, :ensure_login, Proc.new {|c| c.instance_variable_set(:"@ran_proc_action1", true)}, :except => :show_without_action) { |c| c.instance_variable_set(:"@ran_proc_action2", true)}
+    before_action(ConditionalClassFilter, :ensure_login, Proc.new { |c| c.instance_variable_set(:"@ran_proc_action1", true) }, except: :show_without_action) { |c| c.instance_variable_set(:"@ran_proc_action2", true) }
   end
 
   class OnlyConditionalOptionsFilter < ConditionalFilterController
-    before_action :ensure_login, :only => :index, :if => Proc.new {|c| c.instance_variable_set(:"@ran_conditional_index_proc", true) }
+    before_action :ensure_login, only: :index, if: Proc.new { |c| c.instance_variable_set(:"@ran_conditional_index_proc", true) }
   end
 
   class ConditionalOptionsFilter < ConditionalFilterController
-    before_action :ensure_login, :if => Proc.new { |c| true }
-    before_action :clean_up_tmp, :if => Proc.new { |c| false }
+    before_action :ensure_login, if: Proc.new { |c| true }
+    before_action :clean_up_tmp, if: Proc.new { |c| false }
   end
 
   class ConditionalOptionsSkipFilter < ConditionalFilterController
@@ -222,7 +224,7 @@ class FilterTest < ActionController::TestCase
     skip_before_action :clean_up_tmp, only: :login, if: -> { true }
 
     def login
-      render plain: 'ok'
+      render plain: "ok"
     end
   end
 
@@ -234,7 +236,7 @@ class FilterTest < ActionController::TestCase
     skip_before_action :clean_up_tmp, if: -> { true }, except: :login
 
     def login
-      render plain: 'ok'
+      render plain: "ok"
     end
   end
 
@@ -255,14 +257,14 @@ class FilterTest < ActionController::TestCase
 
   class SkippingAndLimitedController < TestController
     skip_before_action :ensure_login
-    before_action :ensure_login, :only => :index
+    before_action :ensure_login, only: :index
 
     def index
-      render plain: 'ok'
+      render plain: "ok"
     end
 
     def public
-      render plain: 'ok'
+      render plain: "ok"
     end
   end
 
@@ -272,7 +274,7 @@ class FilterTest < ActionController::TestCase
     before_action :ensure_login
 
     def index
-      render plain: 'ok'
+      render plain: "ok"
     end
 
     private
@@ -283,20 +285,20 @@ class FilterTest < ActionController::TestCase
   end
 
   class ConditionalSkippingController < TestController
-    skip_before_action :ensure_login, :only => [ :login ]
-    skip_after_action  :clean_up,     :only => [ :login ]
+    skip_before_action :ensure_login, only: [ :login ]
+    skip_after_action  :clean_up,     only: [ :login ]
 
-    before_action :find_user, :only => [ :change_password ]
+    before_action :find_user, only: [ :change_password ]
 
     def login
-      render :inline => "ran action"
+      render inline: "ran action"
     end
 
     def change_password
-      render :inline => "ran action"
+      render inline: "ran action"
     end
 
-    protected
+    private
       def find_user
         @ran_filter ||= []
         @ran_filter << "find_user"
@@ -304,29 +306,29 @@ class FilterTest < ActionController::TestCase
   end
 
   class ConditionalParentOfConditionalSkippingController < ConditionalFilterController
-    before_action :conditional_in_parent_before, :only => [:show, :another_action]
-    after_action  :conditional_in_parent_after, :only => [:show, :another_action]
+    before_action :conditional_in_parent_before, only: [:show, :another_action]
+    after_action  :conditional_in_parent_after, only: [:show, :another_action]
 
     private
 
       def conditional_in_parent_before
         @ran_filter ||= []
-        @ran_filter << 'conditional_in_parent_before'
+        @ran_filter << "conditional_in_parent_before"
       end
 
       def conditional_in_parent_after
         @ran_filter ||= []
-        @ran_filter << 'conditional_in_parent_after'
+        @ran_filter << "conditional_in_parent_after"
       end
   end
 
   class ChildOfConditionalParentController < ConditionalParentOfConditionalSkippingController
-    skip_before_action :conditional_in_parent_before, :only => :another_action
-    skip_after_action  :conditional_in_parent_after, :only => :another_action
+    skip_before_action :conditional_in_parent_before, only: :another_action
+    skip_after_action  :conditional_in_parent_after, only: :another_action
   end
 
   class AnotherChildOfConditionalParentController < ConditionalParentOfConditionalSkippingController
-    skip_before_action :conditional_in_parent_before, :only => :show
+    skip_before_action :conditional_in_parent_before, only: :show
   end
 
   class ProcController < PrependingController
@@ -346,7 +348,7 @@ class FilterTest < ActionController::TestCase
   class AroundFilter
     def before(controller)
       @execution_log = "before"
-      controller.class.execution_log << " before aroundfilter " if controller.respond_to? :execution_log
+      controller.class.execution_log += " before aroundfilter " if controller.respond_to? :execution_log
       controller.instance_variable_set(:"@before_ran", true)
     end
 
@@ -418,17 +420,17 @@ class FilterTest < ActionController::TestCase
     class OutOfOrder < StandardError; end
 
     before_action :first
-    before_action :second, :only => :foo
+    before_action :second, only: :foo
 
     def foo
-      render plain: 'foo'
+      render plain: "foo"
     end
 
     def bar
-      render plain: 'bar'
+      render plain: "bar"
     end
 
-    protected
+    private
       def first
         @first = true
       end
@@ -458,20 +460,20 @@ class FilterTest < ActionController::TestCase
 
     def before_all
       @ran_filter ||= []
-      @ran_filter << 'before_all'
+      @ran_filter << "before_all"
     end
 
     def after_all
       @ran_filter ||= []
-      @ran_filter << 'after_all'
+      @ran_filter << "after_all"
     end
 
     def between_before_all_and_after_all
       @ran_filter ||= []
-      @ran_filter << 'between_before_all_and_after_all'
+      @ran_filter << "between_before_all_and_after_all"
     end
     def show
-      render plain: 'hello'
+      render plain: "hello"
     end
   end
 
@@ -494,50 +496,48 @@ class FilterTest < ActionController::TestCase
   end
 
   class NonYieldingAroundFilterController < ActionController::Base
-
     before_action :filter_one
     around_action :non_yielding_action
     before_action :action_two
     after_action :action_three
 
     def index
-      render :inline => "index"
+      render inline: "index"
     end
 
     private
 
       def filter_one
-        @filters  ||= []
-        @filters  << "filter_one"
+        @filters ||= []
+        @filters << "filter_one"
       end
 
       def action_two
-        @filters  << "action_two"
+        @filters << "action_two"
       end
 
       def non_yielding_action
-        @filters  << "it didn't yield"
+        @filters << "it didn't yield"
       end
 
       def action_three
-        @filters  << "action_three"
+        @filters << "action_three"
       end
-
   end
 
   class ImplicitActionsController < ActionController::Base
-    before_action :find_only, :only => :edit
-    before_action :find_except, :except => :edit
+    before_action :find_only, only: :edit
+    before_action :find_except, except: :edit
 
     private
 
-    def find_only
-      @only = 'Only'
-    end
+      def find_only
+        @only = "Only"
+      end
 
-    def find_except
-      @except = 'Except'
-    end
+      def find_except
+        @except = "Except"
+      end
   end
 
   def test_non_yielding_around_actions_do_not_raise
@@ -586,7 +586,7 @@ class FilterTest < ActionController::TestCase
     assert @controller.instance_variable_get(:@was_audited)
   end
 
-  def test_running_anomolous_yet_valid_condition_actions
+  def test_running_anomalous_yet_valid_condition_actions
     test_process(AnomolousYetValidConditionController)
     assert_equal %w( ensure_login ), @controller.instance_variable_get(:@ran_filter)
     assert @controller.instance_variable_get(:@ran_class_action)
@@ -611,12 +611,12 @@ class FilterTest < ActionController::TestCase
   end
 
   def test_if_is_ignored_when_used_with_only
-    test_process(SkipFilterUsingOnlyAndIf, 'login')
+    test_process(SkipFilterUsingOnlyAndIf, "login")
     assert_not @controller.instance_variable_defined?(:@ran_filter)
   end
 
   def test_except_is_ignored_when_used_with_if
-    test_process(SkipFilterUsingIfAndExcept, 'login')
+    test_process(SkipFilterUsingIfAndExcept, "login")
     assert_equal %w(ensure_login), @controller.instance_variable_get(:@ran_filter)
   end
 
@@ -706,7 +706,7 @@ class FilterTest < ActionController::TestCase
 
   def test_prepending_and_appending_around_action
     test_process(MixedFilterController)
-    assert_equal " before aroundfilter  before procfilter  before appended aroundfilter " +
+    assert_equal " before aroundfilter  before procfilter  before appended aroundfilter " \
                  " after appended aroundfilter  after procfilter  after aroundfilter ",
                  MixedFilterController.execution_log
   end
@@ -745,13 +745,13 @@ class FilterTest < ActionController::TestCase
 
   def test_actions_with_mixed_specialization_run_in_order
     assert_nothing_raised do
-      response = test_process(MixedSpecializationController, 'bar')
-      assert_equal 'bar', response.body
+      response = test_process(MixedSpecializationController, "bar")
+      assert_equal "bar", response.body
     end
 
     assert_nothing_raised do
-      response = test_process(MixedSpecializationController, 'foo')
-      assert_equal 'foo', response.body
+      response = test_process(MixedSpecializationController, "foo")
+      assert_equal "foo", response.body
     end
   end
 
@@ -795,7 +795,7 @@ class FilterTest < ActionController::TestCase
   def test_conditional_skipping_of_actions_when_parent_action_is_also_conditional
     test_process(ChildOfConditionalParentController)
     assert_equal %w( conditional_in_parent_before conditional_in_parent_after ), @controller.instance_variable_get(:@ran_filter)
-    test_process(ChildOfConditionalParentController, 'another_action')
+    test_process(ChildOfConditionalParentController, "another_action")
     assert_not @controller.instance_variable_defined?(:@ran_filter)
   end
 
@@ -824,15 +824,15 @@ class FilterTest < ActionController::TestCase
   end
 
   def test_actions_obey_only_and_except_for_implicit_actions
-    test_process(ImplicitActionsController, 'show')
-    assert_equal 'Except', @controller.instance_variable_get(:@except)
+    test_process(ImplicitActionsController, "show")
+    assert_equal "Except", @controller.instance_variable_get(:@except)
     assert_not @controller.instance_variable_defined?(:@only)
-    assert_equal 'show', response.body
+    assert_equal "show", response.body
 
-    test_process(ImplicitActionsController, 'edit')
-    assert_equal 'Only', @controller.instance_variable_get(:@only)
+    test_process(ImplicitActionsController, "edit")
+    assert_equal "Only", @controller.instance_variable_get(:@only)
     assert_not @controller.instance_variable_defined?(:@except)
-    assert_equal 'edit', response.body
+    assert_equal "edit", response.body
   end
 
   private
@@ -859,14 +859,14 @@ class PostsController < ActionController::Base
 
   private
     def default_action
-      render :inline => "#{action_name} called"
+      render inline: "#{action_name} called"
     end
 end
 
 class ControllerWithSymbolAsFilter < PostsController
-  around_action :raise_before, :only => :raises_before
-  around_action :raise_after, :only => :raises_after
-  around_action :without_exception, :only => :no_raise
+  around_action :raise_before, only: :raises_before
+  around_action :raise_after, only: :raises_after
+  around_action :without_exception, only: :no_raise
 
   private
     def raise_before
@@ -898,7 +898,7 @@ class ControllerWithFilterClass < PostsController
     end
   end
 
-  around_action YieldingFilter, :only => :raises_after
+  around_action YieldingFilter, only: :raises_after
 end
 
 class ControllerWithFilterInstance < PostsController
@@ -909,11 +909,11 @@ class ControllerWithFilterInstance < PostsController
     end
   end
 
-  around_action YieldingFilter.new, :only => :raises_after
+  around_action YieldingFilter.new, only: :raises_after
 end
 
 class ControllerWithProcFilter < PostsController
-  around_action(:only => :no_raise) do |c,b|
+  around_action(only: :no_raise) do |c, b|
     c.instance_variable_set(:"@before", true)
     b.call
     c.instance_variable_set(:"@after", true)
@@ -921,7 +921,7 @@ class ControllerWithProcFilter < PostsController
 end
 
 class ControllerWithNestedFilters < ControllerWithSymbolAsFilter
-  around_action :raise_before, :raise_after, :without_exception, :only => :raises_both
+  around_action :raise_before, :raise_after, :without_exception, only: :raises_both
 end
 
 class ControllerWithAllTypesOfFilters < PostsController
@@ -931,26 +931,26 @@ class ControllerWithAllTypesOfFilters < PostsController
   around_action :around_again
 
   private
-  def before
-    @ran_filter ||= []
-    @ran_filter << 'before'
-  end
+    def before
+      @ran_filter ||= []
+      @ran_filter << "before"
+    end
 
-  def around
-    @ran_filter << 'around (before yield)'
-    yield
-    @ran_filter << 'around (after yield)'
-  end
+    def around
+      @ran_filter << "around (before yield)"
+      yield
+      @ran_filter << "around (after yield)"
+    end
 
-  def after
-    @ran_filter << 'after'
-  end
+    def after
+      @ran_filter << "after"
+    end
 
-  def around_again
-    @ran_filter << 'around_again (before yield)'
-    yield
-    @ran_filter << 'around_again (after yield)'
-  end
+    def around_again
+      @ran_filter << "around_again (before yield)"
+      yield
+      @ran_filter << "around_again (after yield)"
+    end
 end
 
 class ControllerWithTwoLessFilters < ControllerWithAllTypesOfFilters
@@ -958,46 +958,39 @@ class ControllerWithTwoLessFilters < ControllerWithAllTypesOfFilters
   skip_after_action :after
 end
 
-class SkipFilterUsingSkipActionCallback < ControllerWithAllTypesOfFilters
-  ActiveSupport::Deprecation.silence do
-    skip_action_callback :around_again
-    skip_action_callback :after
-  end
-end
-
 class YieldingAroundFiltersTest < ActionController::TestCase
   include PostsController::AroundExceptions
 
   def test_base
     controller = PostsController
-    assert_nothing_raised { test_process(controller,'no_raise') }
-    assert_nothing_raised { test_process(controller,'raises_before') }
-    assert_nothing_raised { test_process(controller,'raises_after') }
-    assert_nothing_raised { test_process(controller,'no_action') }
+    assert_nothing_raised { test_process(controller, "no_raise") }
+    assert_nothing_raised { test_process(controller, "raises_before") }
+    assert_nothing_raised { test_process(controller, "raises_after") }
+    assert_nothing_raised { test_process(controller, "no_action") }
   end
 
   def test_with_symbol
     controller = ControllerWithSymbolAsFilter
-    assert_nothing_raised { test_process(controller,'no_raise') }
-    assert_raise(Before) { test_process(controller,'raises_before') }
-    assert_raise(After) { test_process(controller,'raises_after') }
-    assert_nothing_raised { test_process(controller,'no_raise') }
+    assert_nothing_raised { test_process(controller, "no_raise") }
+    assert_raise(Before) { test_process(controller, "raises_before") }
+    assert_raise(After) { test_process(controller, "raises_after") }
+    assert_nothing_raised { test_process(controller, "no_raise") }
   end
 
   def test_with_class
     controller = ControllerWithFilterClass
-    assert_nothing_raised { test_process(controller,'no_raise') }
-    assert_raise(After) { test_process(controller,'raises_after') }
+    assert_nothing_raised { test_process(controller, "no_raise") }
+    assert_raise(After) { test_process(controller, "raises_after") }
   end
 
   def test_with_instance
     controller = ControllerWithFilterInstance
-    assert_nothing_raised { test_process(controller,'no_raise') }
-    assert_raise(After) { test_process(controller,'raises_after') }
+    assert_nothing_raised { test_process(controller, "no_raise") }
+    assert_raise(After) { test_process(controller, "raises_after") }
   end
 
   def test_with_proc
-    test_process(ControllerWithProcFilter,'no_raise')
+    test_process(ControllerWithProcFilter, "no_raise")
     assert @controller.instance_variable_get(:@before)
     assert @controller.instance_variable_get(:@after)
   end
@@ -1006,71 +999,50 @@ class YieldingAroundFiltersTest < ActionController::TestCase
     controller = ControllerWithNestedFilters
     assert_nothing_raised do
       begin
-        test_process(controller,'raises_both')
+        test_process(controller, "raises_both")
       rescue Before, After
       end
     end
     assert_raise Before do
       begin
-        test_process(controller,'raises_both')
+        test_process(controller, "raises_both")
       rescue After
       end
     end
   end
 
   def test_action_order_with_all_action_types
-    test_process(ControllerWithAllTypesOfFilters,'no_raise')
-    assert_equal 'before around (before yield) around_again (before yield) around_again (after yield) after around (after yield)', @controller.instance_variable_get(:@ran_filter).join(' ')
+    test_process(ControllerWithAllTypesOfFilters, "no_raise")
+    assert_equal "before around (before yield) around_again (before yield) around_again (after yield) after around (after yield)", @controller.instance_variable_get(:@ran_filter).join(" ")
   end
 
   def test_action_order_with_skip_action_method
-    test_process(ControllerWithTwoLessFilters,'no_raise')
-    assert_equal 'before around (before yield) around (after yield)', @controller.instance_variable_get(:@ran_filter).join(' ')
+    test_process(ControllerWithTwoLessFilters, "no_raise")
+    assert_equal "before around (before yield) around (after yield)", @controller.instance_variable_get(:@ran_filter).join(" ")
   end
 
   def test_first_action_in_multiple_before_action_chain_halts
     controller = ::FilterTest::TestMultipleFiltersController.new
-    response = test_process(controller, 'fail_1')
-    assert_equal '', response.body
+    response = test_process(controller, "fail_1")
+    assert_equal "", response.body
     assert_equal 1, controller.instance_variable_get(:@try)
   end
 
   def test_second_action_in_multiple_before_action_chain_halts
     controller = ::FilterTest::TestMultipleFiltersController.new
-    response = test_process(controller, 'fail_2')
-    assert_equal '', response.body
+    response = test_process(controller, "fail_2")
+    assert_equal "", response.body
     assert_equal 2, controller.instance_variable_get(:@try)
   end
 
   def test_last_action_in_multiple_before_action_chain_halts
     controller = ::FilterTest::TestMultipleFiltersController.new
-    response = test_process(controller, 'fail_3')
-    assert_equal '', response.body
+    response = test_process(controller, "fail_3")
+    assert_equal "", response.body
     assert_equal 3, controller.instance_variable_get(:@try)
   end
 
-  def test_skipping_with_skip_action_callback
-    test_process(SkipFilterUsingSkipActionCallback,'no_raise')
-    assert_equal 'before around (before yield) around (after yield)', @controller.instance_variable_get(:@ran_filter).join(' ')
-  end
-
-  def test_deprecated_skip_action_callback
-    assert_deprecated do
-      Class.new(PostsController) do
-        skip_action_callback :clean_up
-      end
-    end
-  end
-
-  def test_deprecated_skip_filter
-    assert_deprecated do
-      Class.new(PostsController) do
-        skip_filter :clean_up
-      end
-    end
-  end
-
-  protected
+  private
     def test_process(controller, action = "show")
       @controller = controller.is_a?(Class) ? controller.new : controller
       process(action)
diff --git a/actionpack/test/controller/flash_hash_test.rb b/actionpack/test/controller/flash_hash_test.rb
index f87077dd86..f31a4d9329 100644
--- a/actionpack/test/controller/flash_hash_test.rb
+++ b/actionpack/test/controller/flash_hash_test.rb
@@ -1,4 +1,6 @@
-require 'abstract_unit'
+# frozen_string_literal: true
+
+require "abstract_unit"
 
 module ActionDispatch
   class FlashHashTest < ActiveSupport::TestCase
@@ -7,116 +9,116 @@ module ActionDispatch
     end
 
     def test_set_get
-      @hash[:foo] = 'zomg'
-      assert_equal 'zomg', @hash[:foo]
+      @hash[:foo] = "zomg"
+      assert_equal "zomg", @hash[:foo]
     end
 
     def test_keys
       assert_equal [], @hash.keys
 
-      @hash['foo'] = 'zomg'
-      assert_equal ['foo'], @hash.keys
+      @hash["foo"] = "zomg"
+      assert_equal ["foo"], @hash.keys
 
-      @hash['bar'] = 'zomg'
-      assert_equal ['foo', 'bar'].sort, @hash.keys.sort
+      @hash["bar"] = "zomg"
+      assert_equal ["foo", "bar"].sort, @hash.keys.sort
     end
 
     def test_update
-      @hash['foo'] = 'bar'
-      @hash.update('foo' => 'baz', 'hello' => 'world')
+      @hash["foo"] = "bar"
+      @hash.update("foo" => "baz", "hello" => "world")
 
-      assert_equal 'baz', @hash['foo']
-      assert_equal 'world', @hash['hello']
+      assert_equal "baz", @hash["foo"]
+      assert_equal "world", @hash["hello"]
     end
 
     def test_key
-      @hash['foo'] = 'bar'
+      @hash["foo"] = "bar"
 
-      assert @hash.key?('foo')
+      assert @hash.key?("foo")
       assert @hash.key?(:foo)
-      assert_not @hash.key?('bar')
+      assert_not @hash.key?("bar")
       assert_not @hash.key?(:bar)
     end
 
     def test_delete
-      @hash['foo'] = 'bar'
-      @hash.delete 'foo'
+      @hash["foo"] = "bar"
+      @hash.delete "foo"
 
-      assert !@hash.key?('foo')
-      assert_nil @hash['foo']
+      assert !@hash.key?("foo")
+      assert_nil @hash["foo"]
     end
 
     def test_to_hash
-      @hash['foo'] = 'bar'
-      assert_equal({'foo' => 'bar'}, @hash.to_hash)
+      @hash["foo"] = "bar"
+      assert_equal({ "foo" => "bar" }, @hash.to_hash)
 
-      @hash.to_hash['zomg'] = 'aaron'
-      assert !@hash.key?('zomg')
-      assert_equal({'foo' => 'bar'}, @hash.to_hash)
+      @hash.to_hash["zomg"] = "aaron"
+      assert !@hash.key?("zomg")
+      assert_equal({ "foo" => "bar" }, @hash.to_hash)
     end
 
     def test_to_session_value
-      @hash['foo'] = 'bar'
-      assert_equal({ 'discard' => [], 'flashes' => { 'foo' => 'bar' } }, @hash.to_session_value)
+      @hash["foo"] = "bar"
+      assert_equal({ "discard" => [], "flashes" => { "foo" => "bar" } }, @hash.to_session_value)
 
-      @hash.now['qux'] = 1
-      assert_equal({ 'flashes' => { 'foo' => 'bar' }, 'discard' => [] }, @hash.to_session_value)
+      @hash.now["qux"] = 1
+      assert_equal({ "flashes" => { "foo" => "bar" }, "discard" => [] }, @hash.to_session_value)
 
-      @hash.discard('foo')
-      assert_equal(nil, @hash.to_session_value)
+      @hash.discard("foo")
+      assert_nil(@hash.to_session_value)
 
       @hash.sweep
-      assert_equal(nil, @hash.to_session_value)
+      assert_nil(@hash.to_session_value)
     end
 
     def test_from_session_value
       # {"session_id"=>"f8e1b8152ba7609c28bbb17ec9263ba7", "flash"=>#<ActionDispatch::Flash::FlashHash:0x00000000000000 @used=#<Set: {"farewell"}>, @closed=false, @flashes={"greeting"=>"Hello", "farewell"=>"Goodbye"}, @now=nil>}
-      rails_3_2_cookie = 'BAh7B0kiD3Nlc3Npb25faWQGOgZFRkkiJWY4ZTFiODE1MmJhNzYwOWMyOGJiYjE3ZWM5MjYzYmE3BjsAVEkiCmZsYXNoBjsARm86JUFjdGlvbkRpc3BhdGNoOjpGbGFzaDo6Rmxhc2hIYXNoCToKQHVzZWRvOghTZXQGOgpAaGFzaHsGSSINZmFyZXdlbGwGOwBUVDoMQGNsb3NlZEY6DUBmbGFzaGVzewdJIg1ncmVldGluZwY7AFRJIgpIZWxsbwY7AFRJIg1mYXJld2VsbAY7AFRJIgxHb29kYnllBjsAVDoJQG5vdzA='
+      rails_3_2_cookie = "BAh7B0kiD3Nlc3Npb25faWQGOgZFRkkiJWY4ZTFiODE1MmJhNzYwOWMyOGJiYjE3ZWM5MjYzYmE3BjsAVEkiCmZsYXNoBjsARm86JUFjdGlvbkRpc3BhdGNoOjpGbGFzaDo6Rmxhc2hIYXNoCToKQHVzZWRvOghTZXQGOgpAaGFzaHsGSSINZmFyZXdlbGwGOwBUVDoMQGNsb3NlZEY6DUBmbGFzaGVzewdJIg1ncmVldGluZwY7AFRJIgpIZWxsbwY7AFRJIg1mYXJld2VsbAY7AFRJIgxHb29kYnllBjsAVDoJQG5vdzA="
       session = Marshal.load(Base64.decode64(rails_3_2_cookie))
-      hash = Flash::FlashHash.from_session_value(session['flash'])
-      assert_equal({'greeting' => 'Hello'}, hash.to_hash)
-      assert_equal(nil, hash.to_session_value)
+      hash = Flash::FlashHash.from_session_value(session["flash"])
+      assert_equal({ "greeting" => "Hello" }, hash.to_hash)
+      assert_nil(hash.to_session_value)
     end
 
     def test_from_session_value_on_json_serializer
       decrypted_data = "{ \"session_id\":\"d98bdf6d129618fc2548c354c161cfb5\", \"flash\":{\"discard\":[\"farewell\"], \"flashes\":{\"greeting\":\"Hello\",\"farewell\":\"Goodbye\"}} }"
       session = ActionDispatch::Cookies::JsonSerializer.load(decrypted_data)
-      hash = Flash::FlashHash.from_session_value(session['flash'])
+      hash = Flash::FlashHash.from_session_value(session["flash"])
 
-      assert_equal({'greeting' => 'Hello'}, hash.to_hash)
-      assert_equal(nil, hash.to_session_value)
+      assert_equal({ "greeting" => "Hello" }, hash.to_hash)
+      assert_nil(hash.to_session_value)
       assert_equal "Hello", hash[:greeting]
       assert_equal "Hello", hash["greeting"]
     end
 
     def test_empty?
       assert @hash.empty?
-      @hash['zomg'] = 'bears'
+      @hash["zomg"] = "bears"
       assert !@hash.empty?
       @hash.clear
       assert @hash.empty?
     end
 
     def test_each
-      @hash['hello'] = 'world'
-      @hash['foo'] = 'bar'
+      @hash["hello"] = "world"
+      @hash["foo"] = "bar"
 
       things = []
-      @hash.each do |k,v|
-        things << [k,v]
+      @hash.each do |k, v|
+        things << [k, v]
       end
 
       assert_equal([%w{ hello world }, %w{ foo bar }].sort, things.sort)
     end
 
     def test_replace
-      @hash['hello'] = 'world'
-      @hash.replace('omg' => 'aaron')
-      assert_equal({'omg' => 'aaron'}, @hash.to_hash)
+      @hash["hello"] = "world"
+      @hash.replace("omg" => "aaron")
+      assert_equal({ "omg" => "aaron" }, @hash.to_hash)
     end
 
     def test_discard_no_args
-      @hash['hello'] = 'world'
+      @hash["hello"] = "world"
       @hash.discard
 
       @hash.sweep
@@ -124,49 +126,49 @@ module ActionDispatch
     end
 
     def test_discard_one_arg
-      @hash['hello'] = 'world'
-      @hash['omg']   = 'world'
-      @hash.discard 'hello'
+      @hash["hello"] = "world"
+      @hash["omg"]   = "world"
+      @hash.discard "hello"
 
       @hash.sweep
-      assert_equal({'omg' => 'world'}, @hash.to_hash)
+      assert_equal({ "omg" => "world" }, @hash.to_hash)
     end
 
     def test_keep_sweep
-      @hash['hello'] = 'world'
+      @hash["hello"] = "world"
 
       @hash.sweep
-      assert_equal({'hello' => 'world'}, @hash.to_hash)
+      assert_equal({ "hello" => "world" }, @hash.to_hash)
     end
 
     def test_update_sweep
-      @hash['hello'] = 'world'
-      @hash.update({'hi' => 'mom'})
+      @hash["hello"] = "world"
+      @hash.update("hi" => "mom")
 
       @hash.sweep
-      assert_equal({'hello' => 'world', 'hi' => 'mom'}, @hash.to_hash)
+      assert_equal({ "hello" => "world", "hi" => "mom" }, @hash.to_hash)
     end
 
     def test_update_delete_sweep
-      @hash['hello'] = 'world'
-      @hash.delete 'hello'
-      @hash.update({'hello' => 'mom'})
+      @hash["hello"] = "world"
+      @hash.delete "hello"
+      @hash.update("hello" => "mom")
 
       @hash.sweep
-      assert_equal({'hello' => 'mom'}, @hash.to_hash)
+      assert_equal({ "hello" => "mom" }, @hash.to_hash)
     end
 
     def test_delete_sweep
-      @hash['hello'] = 'world'
-      @hash['hi']    = 'mom'
-      @hash.delete 'hi'
+      @hash["hello"] = "world"
+      @hash["hi"]    = "mom"
+      @hash.delete "hi"
 
       @hash.sweep
-      assert_equal({'hello' => 'world'}, @hash.to_hash)
+      assert_equal({ "hello" => "world" }, @hash.to_hash)
     end
 
     def test_clear_sweep
-      @hash['hello'] = 'world'
+      @hash["hello"] = "world"
       @hash.clear
 
       @hash.sweep
@@ -174,38 +176,38 @@ module ActionDispatch
     end
 
     def test_replace_sweep
-      @hash['hello'] = 'world'
-      @hash.replace({'hi' => 'mom'})
+      @hash["hello"] = "world"
+      @hash.replace("hi" => "mom")
 
       @hash.sweep
-      assert_equal({'hi' => 'mom'}, @hash.to_hash)
+      assert_equal({ "hi" => "mom" }, @hash.to_hash)
     end
 
     def test_discard_then_add
-      @hash['hello'] = 'world'
-      @hash['omg']   = 'world'
-      @hash.discard 'hello'
-      @hash['hello'] = 'world'
+      @hash["hello"] = "world"
+      @hash["omg"]   = "world"
+      @hash.discard "hello"
+      @hash["hello"] = "world"
 
       @hash.sweep
-      assert_equal({'omg' => 'world', 'hello' => 'world'}, @hash.to_hash)
+      assert_equal({ "omg" => "world", "hello" => "world" }, @hash.to_hash)
     end
 
     def test_keep_all_sweep
-      @hash['hello'] = 'world'
-      @hash['omg']   = 'world'
-      @hash.discard 'hello'
+      @hash["hello"] = "world"
+      @hash["omg"]   = "world"
+      @hash.discard "hello"
       @hash.keep
 
       @hash.sweep
-      assert_equal({'omg' => 'world', 'hello' => 'world'}, @hash.to_hash)
+      assert_equal({ "omg" => "world", "hello" => "world" }, @hash.to_hash)
     end
 
     def test_double_sweep
-      @hash['hello'] = 'world'
+      @hash["hello"] = "world"
       @hash.sweep
 
-      assert_equal({'hello' => 'world'}, @hash.to_hash)
+      assert_equal({ "hello" => "world" }, @hash.to_hash)
 
       @hash.sweep
       assert_equal({}, @hash.to_hash)
diff --git a/actionpack/test/controller/flash_test.rb b/actionpack/test/controller/flash_test.rb
index eef48e8480..34bc2c0caa 100644
--- a/actionpack/test/controller/flash_test.rb
+++ b/actionpack/test/controller/flash_test.rb
@@ -1,11 +1,13 @@
-require 'abstract_unit'
-require 'active_support/key_generator'
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "active_support/messages/rotation_configuration"
 
 class FlashTest < ActionController::TestCase
   class TestController < ActionController::Base
     def set_flash
       flash["that"] = "hello"
-      render :inline => "hello"
+      render inline: "hello"
     end
 
     def set_flash_now
@@ -14,32 +16,32 @@ class FlashTest < ActionController::TestCase
       flash.now["foo"] ||= "err"
       @flashy = flash.now["that"]
       @flash_copy = {}.update flash
-      render :inline => "hello"
+      render inline: "hello"
     end
 
     def attempt_to_use_flash_now
       @flash_copy = {}.update flash
       @flashy = flash["that"]
-      render :inline => "hello"
+      render inline: "hello"
     end
 
     def use_flash
       @flash_copy = {}.update flash
       @flashy = flash["that"]
-      render :inline => "hello"
+      render inline: "hello"
     end
 
     def use_flash_and_keep_it
       @flash_copy = {}.update flash
       @flashy = flash["that"]
       flash.keep
-      render :inline => "hello"
+      render inline: "hello"
     end
 
     def use_flash_and_update_it
       flash.update("this" => "hello again")
       @flash_copy = {}.update flash
-      render :inline => "hello"
+      render inline: "hello"
     end
 
     def use_flash_after_reset_session
@@ -49,11 +51,11 @@ class FlashTest < ActionController::TestCase
       @flashy_that_reset = flash["that"]
       flash["this"] = "good-bye"
       @flashy_this = flash["this"]
-      render :inline => "hello"
+      render inline: "hello"
     end
 
     # methods for test_sweep_after_halted_action_chain
-    before_action :halt_and_redir, only: 'filter_halting_action'
+    before_action :halt_and_redir, only: "filter_halting_action"
 
     def std_action
       @flash_copy = {}.update(flash)
@@ -66,34 +68,34 @@ class FlashTest < ActionController::TestCase
 
     def halt_and_redir
       flash["foo"] = "bar"
-      redirect_to :action => "std_action"
+      redirect_to action: "std_action"
       @flash_copy = {}.update(flash)
     end
 
     def redirect_with_alert
-      redirect_to '/nowhere', :alert => "Beware the nowheres!"
+      redirect_to "/nowhere", alert: "Beware the nowheres!"
     end
 
     def redirect_with_notice
-      redirect_to '/somewhere', :notice => "Good luck in the somewheres!"
+      redirect_to "/somewhere", notice: "Good luck in the somewheres!"
     end
 
     def render_with_flash_now_alert
       flash.now.alert = "Beware the nowheres now!"
-      render :inline => "hello"
+      render inline: "hello"
     end
 
     def render_with_flash_now_notice
       flash.now.notice = "Good luck in the somewheres now!"
-      render :inline => "hello"
+      render inline: "hello"
     end
 
     def redirect_with_other_flashes
-      redirect_to '/wonderland', :flash => { :joyride => "Horses!" }
+      redirect_to "/wonderland", flash: { joyride: "Horses!" }
     end
 
     def redirect_with_foo_flash
-      redirect_to "/wonderland", :foo => 'for great justice'
+      redirect_to "/wonderland", foo: "for great justice"
     end
   end
 
@@ -172,17 +174,17 @@ class FlashTest < ActionController::TestCase
 
   def test_keep_and_discard_return_values
     flash = ActionDispatch::Flash::FlashHash.new
-    flash.update(:foo => :foo_indeed, :bar => :bar_indeed)
+    flash.update(foo: :foo_indeed, bar: :bar_indeed)
 
     assert_equal(:foo_indeed, flash.discard(:foo)) # valid key passed
     assert_nil flash.discard(:unknown) # non existent key passed
-    assert_equal({"foo" => :foo_indeed, "bar" => :bar_indeed}, flash.discard().to_hash) # nothing passed
-    assert_equal({"foo" => :foo_indeed, "bar" => :bar_indeed}, flash.discard(nil).to_hash) # nothing passed
+    assert_equal({ "foo" => :foo_indeed, "bar" => :bar_indeed }, flash.discard().to_hash) # nothing passed
+    assert_equal({ "foo" => :foo_indeed, "bar" => :bar_indeed }, flash.discard(nil).to_hash) # nothing passed
 
     assert_equal(:foo_indeed, flash.keep(:foo)) # valid key passed
     assert_nil flash.keep(:unknown) # non existent key passed
-    assert_equal({"foo" => :foo_indeed, "bar" => :bar_indeed}, flash.keep().to_hash) # nothing passed
-    assert_equal({"foo" => :foo_indeed, "bar" => :bar_indeed}, flash.keep(nil).to_hash) # nothing passed
+    assert_equal({ "foo" => :foo_indeed, "bar" => :bar_indeed }, flash.keep().to_hash) # nothing passed
+    assert_equal({ "foo" => :foo_indeed, "bar" => :bar_indeed }, flash.keep(nil).to_hash) # nothing passed
   end
 
   def test_redirect_to_with_alert
@@ -227,7 +229,7 @@ class FlashTest < ActionController::TestCase
       add_flash_types :foo
     end
     subclass_controller_with_no_flash_type = Class.new(test_controller_with_flash_type_foo)
-    assert subclass_controller_with_no_flash_type._flash_types.include?(:foo)
+    assert_includes subclass_controller_with_no_flash_type._flash_types, :foo
   end
 
   def test_does_not_add_flash_type_to_parent_class
@@ -239,8 +241,9 @@ class FlashTest < ActionController::TestCase
 end
 
 class FlashIntegrationTest < ActionDispatch::IntegrationTest
-  SessionKey = '_myapp_session'
-  Generator  = ActiveSupport::LegacyKeyGenerator.new('b3c631c314c0bbca50c1b2843150fe33')
+  SessionKey = "_myapp_session"
+  Generator  = ActiveSupport::LegacyKeyGenerator.new("b3c631c314c0bbca50c1b2843150fe33")
+  Rotations  = ActiveSupport::Messages::RotationConfiguration.new
 
   class TestController < ActionController::Base
     add_flash_types :bar
@@ -256,22 +259,29 @@ class FlashIntegrationTest < ActionDispatch::IntegrationTest
     end
 
     def use_flash
-      render :inline => "flash: #{flash["that"]}"
+      render inline: "flash: #{flash["that"]}"
     end
 
     def set_bar
       flash[:bar] = "for great justice"
       head :ok
     end
+
+    def set_flash_optionally
+      flash.now.notice = params[:flash]
+      if stale? etag: "abe"
+        render inline: "maybe flash"
+      end
+    end
   end
 
   def test_flash
     with_test_route_set do
-      get '/set_flash'
+      get "/set_flash"
       assert_response :success
       assert_equal "hello", @request.flash["that"]
 
-      get '/use_flash'
+      get "/use_flash"
       assert_response :success
       assert_equal "flash: hello", @response.body
     end
@@ -279,7 +289,7 @@ class FlashIntegrationTest < ActionDispatch::IntegrationTest
 
   def test_just_using_flash_does_not_stream_a_cookie_back
     with_test_route_set do
-      get '/use_flash'
+      get "/use_flash"
       assert_response :success
       assert_nil @response.headers["Set-Cookie"]
       assert_equal "flash: ", @response.body
@@ -288,25 +298,47 @@ class FlashIntegrationTest < ActionDispatch::IntegrationTest
 
   def test_setting_flash_does_not_raise_in_following_requests
     with_test_route_set do
-      env = { 'action_dispatch.request.flash_hash' => ActionDispatch::Flash::FlashHash.new }
-      get '/set_flash', env: env
-      get '/set_flash', env: env
+      env = { "action_dispatch.request.flash_hash" => ActionDispatch::Flash::FlashHash.new }
+      get "/set_flash", env: env
+      get "/set_flash", env: env
     end
   end
 
   def test_setting_flash_now_does_not_raise_in_following_requests
     with_test_route_set do
-      env = { 'action_dispatch.request.flash_hash' => ActionDispatch::Flash::FlashHash.new }
-      get '/set_flash_now', env: env
-      get '/set_flash_now', env: env
+      env = { "action_dispatch.request.flash_hash" => ActionDispatch::Flash::FlashHash.new }
+      get "/set_flash_now", env: env
+      get "/set_flash_now", env: env
     end
   end
 
   def test_added_flash_types_method
     with_test_route_set do
-      get '/set_bar'
+      get "/set_bar"
       assert_response :success
-      assert_equal 'for great justice', @controller.bar
+      assert_equal "for great justice", @controller.bar
+    end
+  end
+
+  def test_flash_factored_into_etag
+    with_test_route_set do
+      get "/set_flash_optionally"
+      no_flash_etag = response.etag
+
+      get "/set_flash_optionally", params: { flash: "hello!" }
+      hello_flash_etag = response.etag
+
+      assert_not_equal no_flash_etag, hello_flash_etag
+
+      get "/set_flash_optionally", params: { flash: "hello!" }
+      another_hello_flash_etag = response.etag
+
+      assert_equal another_hello_flash_etag, hello_flash_etag
+
+      get "/set_flash_optionally", params: { flash: "goodbye!" }
+      goodbye_flash_etag = response.etag
+
+      assert_not_equal another_hello_flash_etag, goodbye_flash_etag
     end
   end
 
@@ -317,6 +349,7 @@ class FlashIntegrationTest < ActionDispatch::IntegrationTest
       args[0] ||= {}
       args[0][:env] ||= {}
       args[0][:env]["action_dispatch.key_generator"] ||= Generator
+      args[0][:env]["action_dispatch.cookies_rotations"] = Rotations
       super(path, *args)
     end
 
@@ -324,12 +357,12 @@ class FlashIntegrationTest < ActionDispatch::IntegrationTest
       with_routing do |set|
         set.draw do
           ActiveSupport::Deprecation.silence do
-            get ':action', :to => FlashIntegrationTest::TestController
+            get ":action", to: FlashIntegrationTest::TestController
           end
         end
 
         @app = self.class.build_app(set) do |middleware|
-          middleware.use ActionDispatch::Session::CookieStore, :key => SessionKey
+          middleware.use ActionDispatch::Session::CookieStore, key: SessionKey
           middleware.use ActionDispatch::Flash
           middleware.delete ActionDispatch::ShowExceptions
         end
diff --git a/actionpack/test/controller/force_ssl_test.rb b/actionpack/test/controller/force_ssl_test.rb
index 03a9c9ae78..84ac1fda3c 100644
--- a/actionpack/test/controller/force_ssl_test.rb
+++ b/actionpack/test/controller/force_ssl_test.rb
@@ -1,4 +1,6 @@
-require 'abstract_unit'
+# frozen_string_literal: true
+
+require "abstract_unit"
 
 class ForceSSLController < ActionController::Base
   def banana
@@ -15,15 +17,15 @@ class ForceSSLControllerLevel < ForceSSLController
 end
 
 class ForceSSLCustomOptions < ForceSSLController
-  force_ssl :host => "secure.example.com", :only => :redirect_host
-  force_ssl :port => 8443, :only => :redirect_port
-  force_ssl :subdomain => 'secure', :only => :redirect_subdomain
-  force_ssl :domain => 'secure.com', :only => :redirect_domain
-  force_ssl :path => '/foo', :only => :redirect_path
-  force_ssl :status => :found, :only => :redirect_status
-  force_ssl :flash => { :message => 'Foo, Bar!' }, :only => :redirect_flash
-  force_ssl :alert => 'Foo, Bar!', :only => :redirect_alert
-  force_ssl :notice => 'Foo, Bar!', :only => :redirect_notice
+  force_ssl host: "secure.example.com", only: :redirect_host
+  force_ssl port: 8443, only: :redirect_port
+  force_ssl subdomain: "secure", only: :redirect_subdomain
+  force_ssl domain: "secure.com", only: :redirect_domain
+  force_ssl path: "/foo", only: :redirect_path
+  force_ssl status: :found, only: :redirect_status
+  force_ssl flash: { message: "Foo, Bar!" }, only: :redirect_flash
+  force_ssl alert: "Foo, Bar!", only: :redirect_alert
+  force_ssl notice: "Foo, Bar!", only: :redirect_notice
 
   def force_ssl_action
     render plain: action_name
@@ -53,42 +55,42 @@ class ForceSSLCustomOptions < ForceSSLController
 end
 
 class ForceSSLOnlyAction < ForceSSLController
-  force_ssl :only => :cheeseburger
+  force_ssl only: :cheeseburger
 end
 
 class ForceSSLExceptAction < ForceSSLController
-  force_ssl :except => :banana
+  force_ssl except: :banana
 end
 
 class ForceSSLIfCondition < ForceSSLController
-  force_ssl :if => :use_force_ssl?
+  force_ssl if: :use_force_ssl?
 
   def use_force_ssl?
-    action_name == 'cheeseburger'
+    action_name == "cheeseburger"
   end
 end
 
 class ForceSSLFlash < ForceSSLController
-  force_ssl :except => [:banana, :set_flash, :use_flash]
+  force_ssl except: [:banana, :set_flash, :use_flash]
 
   def set_flash
     flash["that"] = "hello"
-    redirect_to '/force_ssl_flash/cheeseburger'
+    redirect_to "/force_ssl_flash/cheeseburger"
   end
 
   def use_flash
     @flash_copy = {}.update flash
     @flashy = flash["that"]
-    render :inline => "hello"
+    render inline: "hello"
   end
 end
 
 class RedirectToSSL < ForceSSLController
   def banana
-    force_ssl_redirect || render(plain: 'monkey')
+    force_ssl_redirect || render(plain: "monkey")
   end
   def cheeseburger
-    force_ssl_redirect('secure.cheeseburger.host') || render(plain: 'ihaz')
+    force_ssl_redirect("secure.cheeseburger.host") || render(plain: "ihaz")
   end
 end
 
@@ -114,7 +116,7 @@ end
 
 class ForceSSLCustomOptionsTest < ActionController::TestCase
   def setup
-    @request.env['HTTP_HOST'] = 'www.example.com:80'
+    @request.env["HTTP_HOST"] = "www.example.com:80"
   end
 
   def test_redirect_to_custom_host
@@ -229,15 +231,13 @@ class ForceSSLFlashTest < ActionController::TestCase
     assert_response 302
     assert_equal "http://test.host/force_ssl_flash/cheeseburger", redirect_to_url
 
-    # FIXME: AC::TestCase#build_request_uri doesn't build a new uri if PATH_INFO exists
-    @request.env.delete('PATH_INFO')
+    @request.env.delete("PATH_INFO")
 
     get :cheeseburger
     assert_response 301
     assert_equal "https://test.host/force_ssl_flash/cheeseburger", redirect_to_url
 
-    # FIXME: AC::TestCase#build_request_uri doesn't build a new uri if PATH_INFO exists
-    @request.env.delete('PATH_INFO')
+    @request.env.delete("PATH_INFO")
 
     get :use_flash
     assert_equal "hello", @controller.instance_variable_get("@flash_copy")["that"]
@@ -251,15 +251,15 @@ class ForceSSLDuplicateRoutesTest < ActionController::TestCase
   def test_force_ssl_redirects_to_same_path
     with_routing do |set|
       set.draw do
-        get '/foo', :to => 'force_ssl_controller_level#banana'
-        get '/bar', :to => 'force_ssl_controller_level#banana'
+        get "/foo", to: "force_ssl_controller_level#banana"
+        get "/bar", to: "force_ssl_controller_level#banana"
       end
 
-      @request.env['PATH_INFO'] = '/bar'
+      @request.env["PATH_INFO"] = "/bar"
 
       get :banana
       assert_response 301
-      assert_equal 'https://test.host/bar', redirect_to_url
+      assert_equal "https://test.host/bar", redirect_to_url
     end
   end
 end
@@ -270,12 +270,12 @@ class ForceSSLFormatTest < ActionController::TestCase
   def test_force_ssl_redirects_to_same_format
     with_routing do |set|
       set.draw do
-        get '/foo', :to => 'force_ssl_controller_level#banana'
+        get "/foo", to: "force_ssl_controller_level#banana"
       end
 
       get :banana, format: :json
       assert_response 301
-      assert_equal 'https://test.host/foo.json', redirect_to_url
+      assert_equal "https://test.host/foo.json", redirect_to_url
     end
   end
 end
@@ -286,18 +286,18 @@ class ForceSSLOptionalSegmentsTest < ActionController::TestCase
   def test_force_ssl_redirects_to_same_format
     with_routing do |set|
       set.draw do
-        scope '(:locale)' do
-          defaults :locale => 'en' do
-            get '/foo', :to => 'force_ssl_controller_level#banana'
+        scope "(:locale)" do
+          defaults locale: "en" do
+            get "/foo", to: "force_ssl_controller_level#banana"
           end
         end
       end
 
-      @request.env['PATH_INFO'] = '/en/foo'
-      get :banana, params: { locale: 'en' }
-      assert_equal 'en',  @controller.params[:locale]
+      @request.env["PATH_INFO"] = "/en/foo"
+      get :banana, params: { locale: "en" }
+      assert_equal "en",  @controller.params[:locale]
       assert_response 301
-      assert_equal 'https://test.host/en/foo', redirect_to_url
+      assert_equal "https://test.host/en/foo", redirect_to_url
     end
   end
 end
@@ -316,17 +316,17 @@ class RedirectToSSLTest < ActionController::TestCase
   end
 
   def test_cheeseburgers_does_not_redirect_if_already_https
-    request.env['HTTPS'] = 'on'
+    request.env["HTTPS"] = "on"
     get :cheeseburger
     assert_response 200
-    assert_equal 'ihaz', response.body
+    assert_equal "ihaz", response.body
   end
 end
 
 class ForceSSLControllerLevelTest < ActionController::TestCase
   def test_no_redirect_websocket_ssl_request
-    request.env['rack.url_scheme'] = 'wss'
-    request.env['Upgrade'] = 'websocket'
+    request.env["rack.url_scheme"] = "wss"
+    request.env["Upgrade"] = "websocket"
     get :cheeseburger
     assert_response 200
   end
diff --git a/actionpack/test/controller/form_builder_test.rb b/actionpack/test/controller/form_builder_test.rb
index 99eeaf9ab6..2db0834c5e 100644
--- a/actionpack/test/controller/form_builder_test.rb
+++ b/actionpack/test/controller/form_builder_test.rb
@@ -1,4 +1,6 @@
-require 'abstract_unit'
+# frozen_string_literal: true
+
+require "abstract_unit"
 
 class FormBuilderController < ActionController::Base
   class SpecializedFormBuilder < ActionView::Helpers::FormBuilder ; end
diff --git a/actionpack/test/controller/helper_test.rb b/actionpack/test/controller/helper_test.rb
index ef85e141a0..de8072a994 100644
--- a/actionpack/test/controller/helper_test.rb
+++ b/actionpack/test/controller/helper_test.rb
@@ -1,17 +1,19 @@
-require 'abstract_unit'
+# frozen_string_literal: true
 
-ActionController::Base.helpers_path = File.expand_path('../../fixtures/helpers', __FILE__)
+require "abstract_unit"
+
+ActionController::Base.helpers_path = File.expand_path("../fixtures/helpers", __dir__)
 
 module Fun
   class GamesController < ActionController::Base
     def render_hello_world
-      render :inline => "hello: <%= stratego %>"
+      render inline: "hello: <%= stratego %>"
     end
   end
 
   class PdfController < ActionController::Base
     def test
-      render :inline => "test: <%= foobar %>"
+      render inline: "test: <%= foobar %>"
     end
   end
 end
@@ -35,11 +37,11 @@ class JustMeController < ActionController::Base
   clear_helpers
 
   def flash
-    render :inline => "<h1><%= notice %></h1>"
+    render inline: "<h1><%= notice %></h1>"
   end
 
   def lib
-    render :inline => '<%= useful_function %>'
+    render inline: "<%= useful_function %>"
   end
 end
 
@@ -48,7 +50,7 @@ end
 
 class HelpersPathsController < ActionController::Base
   paths = ["helpers2_pack", "helpers1_pack"].map do |path|
-    File.join(File.expand_path('../../fixtures', __FILE__), path)
+    File.join(File.expand_path("../fixtures", __dir__), path)
   end
   $:.unshift(*paths)
 
@@ -56,12 +58,12 @@ class HelpersPathsController < ActionController::Base
   helper :all
 
   def index
-    render :inline => "<%= conflicting_helper %>"
+    render inline: "<%= conflicting_helper %>"
   end
 end
 
 class HelpersTypoController < ActionController::Base
-  path = File.expand_path('../../fixtures/helpers_typo', __FILE__)
+  path = File.expand_path("../fixtures/helpers_typo", __dir__)
   $:.unshift(path)
   self.helpers_path = path
 end
@@ -89,7 +91,7 @@ class HelpersTypoControllerTest < ActiveSupport::TestCase
   end
 
   def test_helper_typo_error_message
-    e = assert_raise(NameError) { HelpersTypoController.helper 'admin/users' }
+    e = assert_raise(NameError) { HelpersTypoController.helper "admin/users" }
     assert_equal "Couldn't find Admin::UsersHelper, expected it to be defined in helpers/admin/users_helper.rb", e.message
   end
 
@@ -106,7 +108,7 @@ class HelperTest < ActiveSupport::TestCase
 
   def setup
     # Increment symbol counter.
-    @symbol = (@@counter ||= 'A0').succ!.dup
+    @symbol = (@@counter ||= "A0").succ.dup
 
     # Generate new controller class.
     controller_class_name = "Helper#{@symbol}Controller"
@@ -125,13 +127,13 @@ class HelperTest < ActiveSupport::TestCase
 
   def test_helper_method
     assert_nothing_raised { @controller_class.helper_method :delegate_method }
-    assert master_helper_methods.include?(:delegate_method)
+    assert_includes master_helper_methods, :delegate_method
   end
 
   def test_helper_attr
     assert_nothing_raised { @controller_class.helper_attr :delegate_attr }
-    assert master_helper_methods.include?(:delegate_attr)
-    assert master_helper_methods.include?(:delegate_attr=)
+    assert_includes master_helper_methods, :delegate_attr
+    assert_includes master_helper_methods, :delegate_attr=
   end
 
   def call_controller(klass, action)
@@ -139,7 +141,7 @@ class HelperTest < ActiveSupport::TestCase
   end
 
   def test_helper_for_nested_controller
-    assert_equal 'hello: Iz guuut!',
+    assert_equal "hello: Iz guuut!",
       call_controller(Fun::GamesController, "render_hello_world").last.body
   end
 
@@ -168,43 +170,43 @@ class HelperTest < ActiveSupport::TestCase
     methods = AllHelpersController._helpers.instance_methods
 
     # abc_helper.rb
-    assert methods.include?(:bare_a)
+    assert_includes methods, :bare_a
 
     # fun/games_helper.rb
-    assert methods.include?(:stratego)
+    assert_includes methods, :stratego
 
     # fun/pdf_helper.rb
-    assert methods.include?(:foobar)
+    assert_includes methods, :foobar
   end
 
   def test_all_helpers_with_alternate_helper_dir
-    @controller_class.helpers_path = File.expand_path('../../fixtures/alternate_helpers', __FILE__)
+    @controller_class.helpers_path = File.expand_path("../fixtures/alternate_helpers", __dir__)
 
     # Reload helpers
     @controller_class._helpers = Module.new
     @controller_class.helper :all
 
     # helpers/abc_helper.rb should not be included
-    assert !master_helper_methods.include?(:bare_a)
+    assert_not_includes master_helper_methods, :bare_a
 
     # alternate_helpers/foo_helper.rb
-    assert master_helper_methods.include?(:baz)
+    assert_includes master_helper_methods, :baz
   end
 
   def test_helper_proxy
     methods = AllHelpersController.helpers.methods
 
     # Action View
-    assert methods.include?(:pluralize)
+    assert_includes methods, :pluralize
 
     # abc_helper.rb
-    assert methods.include?(:bare_a)
+    assert_includes methods, :bare_a
 
     # fun/games_helper.rb
-    assert methods.include?(:stratego)
+    assert_includes methods, :stratego
 
     # fun/pdf_helper.rb
-    assert methods.include?(:foobar)
+    assert_includes methods, :foobar
   end
 
   def test_helper_proxy_in_instance
@@ -224,9 +226,9 @@ class HelperTest < ActiveSupport::TestCase
   end
 
   def test_helper_proxy_config
-    AllHelpersController.config.my_var = 'smth'
+    AllHelpersController.config.my_var = "smth"
 
-    assert_equal 'smth', AllHelpersController.helpers.config.my_var
+    assert_equal "smth", AllHelpersController.helpers.config.my_var
   end
 
   private
@@ -243,31 +245,30 @@ class HelperTest < ActiveSupport::TestCase
     end
 
     def test_helper=(helper_module)
-      silence_warnings { self.class.const_set('TestHelper', helper_module) }
+      silence_warnings { self.class.const_set("TestHelper", helper_module) }
     end
 end
 
-
 class IsolatedHelpersTest < ActionController::TestCase
   class A < ActionController::Base
     def index
-      render :inline => '<%= shout %>'
+      render inline: "<%= shout %>"
     end
   end
 
   class B < A
-    helper { def shout; 'B' end }
+    helper { def shout; "B" end }
 
     def index
-      render :inline => '<%= shout %>'
+      render inline: "<%= shout %>"
     end
   end
 
   class C < A
-    helper { def shout; 'C' end }
+    helper { def shout; "C" end }
 
     def index
-      render :inline => '<%= shout %>'
+      render inline: "<%= shout %>"
     end
   end
 
@@ -277,7 +278,7 @@ class IsolatedHelpersTest < ActionController::TestCase
 
   def setup
     super
-    @request.action = 'index'
+    @request.action = "index"
   end
 
   def test_helper_in_a
@@ -285,10 +286,10 @@ class IsolatedHelpersTest < ActionController::TestCase
   end
 
   def test_helper_in_b
-    assert_equal 'B', call_controller(B, "index").last.body
+    assert_equal "B", call_controller(B, "index").last.body
   end
 
   def test_helper_in_c
-    assert_equal 'C', call_controller(C, "index").last.body
+    assert_equal "C", call_controller(C, "index").last.body
   end
 end
diff --git a/actionpack/test/controller/http_basic_authentication_test.rb b/actionpack/test/controller/http_basic_authentication_test.rb
index adcf259317..1544a627ee 100644
--- a/actionpack/test/controller/http_basic_authentication_test.rb
+++ b/actionpack/test/controller/http_basic_authentication_test.rb
@@ -1,4 +1,6 @@
-require 'abstract_unit'
+# frozen_string_literal: true
+
+require "abstract_unit"
 
 class HttpBasicAuthenticationTest < ActionController::TestCase
   class DummyController < ActionController::Base
@@ -7,88 +9,88 @@ class HttpBasicAuthenticationTest < ActionController::TestCase
     before_action :authenticate_long_credentials, only: :show
     before_action :auth_with_special_chars, only: :special_creds
 
-    http_basic_authenticate_with :name => "David", :password => "Goliath", :only => :search
+    http_basic_authenticate_with name: "David", password: "Goliath", only: :search
 
     def index
       render plain: "Hello Secret"
     end
 
     def display
-      render plain: 'Definitely Maybe' if @logged_in
+      render plain: "Definitely Maybe" if @logged_in
     end
 
     def show
-      render plain: 'Only for loooooong credentials'
+      render plain: "Only for loooooong credentials"
     end
 
     def special_creds
-      render plain: 'Only for special credentials'
+      render plain: "Only for special credentials"
     end
 
     def search
-      render plain: 'All inline'
+      render plain: "All inline"
     end
 
     private
 
-    def authenticate
-      authenticate_or_request_with_http_basic do |username, password|
-        username == 'lifo' && password == 'world'
+      def authenticate
+        authenticate_or_request_with_http_basic do |username, password|
+          username == "lifo" && password == "world"
+        end
       end
-    end
 
-    def authenticate_with_request
-      if authenticate_with_http_basic { |username, password| username == 'pretty' && password == 'please' }
-        @logged_in = true
-      else
-        request_http_basic_authentication("SuperSecret", "Authentication Failed\n")
+      def authenticate_with_request
+        if authenticate_with_http_basic { |username, password| username == "pretty" && password == "please" }
+          @logged_in = true
+        else
+          request_http_basic_authentication("SuperSecret", "Authentication Failed\n")
+        end
       end
-    end
 
-    def auth_with_special_chars
-      authenticate_or_request_with_http_basic do |username, password|
-        username == 'login!@#$%^&*()_+{}[];"\',./<>?`~ \n\r\t' && password == 'pwd:!@#$%^&*()_+{}[];"\',./<>?`~ \n\r\t'
+      def auth_with_special_chars
+        authenticate_or_request_with_http_basic do |username, password|
+          username == 'login!@#$%^&*()_+{}[];"\',./<>?`~ \n\r\t' && password == 'pwd:!@#$%^&*()_+{}[];"\',./<>?`~ \n\r\t'
+        end
       end
-    end
 
-    def authenticate_long_credentials
-      authenticate_or_request_with_http_basic do |username, password|
-        username == '1234567890123456789012345678901234567890' && password == '1234567890123456789012345678901234567890'
+      def authenticate_long_credentials
+        authenticate_or_request_with_http_basic do |username, password|
+          username == "1234567890123456789012345678901234567890" && password == "1234567890123456789012345678901234567890"
+        end
       end
-    end
   end
 
-  AUTH_HEADERS = ['HTTP_AUTHORIZATION', 'X-HTTP_AUTHORIZATION', 'X_HTTP_AUTHORIZATION', 'REDIRECT_X_HTTP_AUTHORIZATION']
+  AUTH_HEADERS = ["HTTP_AUTHORIZATION", "X-HTTP_AUTHORIZATION", "X_HTTP_AUTHORIZATION", "REDIRECT_X_HTTP_AUTHORIZATION"]
 
   tests DummyController
 
   AUTH_HEADERS.each do |header|
     test "successful authentication with #{header.downcase}" do
-      @request.env[header] = encode_credentials('lifo', 'world')
+      @request.env[header] = encode_credentials("lifo", "world")
       get :index
 
       assert_response :success
-      assert_equal 'Hello Secret', @response.body, "Authentication failed for request header #{header}"
+      assert_equal "Hello Secret", @response.body, "Authentication failed for request header #{header}"
     end
     test "successful authentication with #{header.downcase} and long credentials" do
-      @request.env[header] = encode_credentials('1234567890123456789012345678901234567890', '1234567890123456789012345678901234567890')
+      @request.env[header] = encode_credentials("1234567890123456789012345678901234567890", "1234567890123456789012345678901234567890")
       get :show
 
       assert_response :success
-      assert_equal 'Only for loooooong credentials', @response.body, "Authentication failed for request header #{header} and long credentials"
+      assert_equal "Only for loooooong credentials", @response.body, "Authentication failed for request header #{header} and long credentials"
     end
   end
 
   AUTH_HEADERS.each do |header|
     test "unsuccessful authentication with #{header.downcase}" do
-      @request.env[header] = encode_credentials('h4x0r', 'world')
+      @request.env[header] = encode_credentials("h4x0r", "world")
       get :index
 
       assert_response :unauthorized
       assert_equal "HTTP Basic: Access denied.\n", @response.body, "Authentication didn't fail for request header #{header}"
     end
     test "unsuccessful authentication with #{header.downcase} and long credentials" do
-      @request.env[header] = encode_credentials('h4x0rh4x0rh4x0rh4x0rh4x0rh4x0rh4x0rh4x0r', 'worldworldworldworldworldworldworldworld')
+      @request.env[header] = encode_credentials("h4x0rh4x0rh4x0rh4x0rh4x0rh4x0rh4x0rh4x0r", "worldworldworldworldworldworldworldworld")
       get :show
 
       assert_response :unauthorized
@@ -104,19 +106,19 @@ class HttpBasicAuthenticationTest < ActionController::TestCase
   end
 
   def test_encode_credentials_has_no_newline
-    username = 'laskjdfhalksdjfhalkjdsfhalksdjfhklsdjhalksdjfhalksdjfhlakdsjfh'
-    password = 'kjfhueyt9485osdfasdkljfh4lkjhakldjfhalkdsjf'
+    username = "laskjdfhalksdjfhalkjdsfhalksdjfhklsdjhalksdjfhalksdjfhlakdsjfh"
+    password = "kjfhueyt9485osdfasdkljfh4lkjhakldjfhalkdsjf"
     result = ActionController::HttpAuthentication::Basic.encode_credentials(
       username, password)
     assert_no_match(/\n/, result)
   end
 
   test "successful authentication with uppercase authorization scheme" do
-    @request.env['HTTP_AUTHORIZATION'] = "BASIC #{::Base64.encode64("lifo:world")}"
+    @request.env["HTTP_AUTHORIZATION"] = "BASIC #{::Base64.encode64("lifo:world")}"
     get :index
 
     assert_response :success
-    assert_equal 'Hello Secret', @response.body, 'Authentication failed when authorization scheme BASIC'
+    assert_equal "Hello Secret", @response.body, "Authentication failed when authorization scheme BASIC"
   end
 
   test "authentication request without credential" do
@@ -124,54 +126,54 @@ class HttpBasicAuthenticationTest < ActionController::TestCase
 
     assert_response :unauthorized
     assert_equal "Authentication Failed\n", @response.body
-    assert_equal 'Basic realm="SuperSecret"', @response.headers['WWW-Authenticate']
+    assert_equal 'Basic realm="SuperSecret"', @response.headers["WWW-Authenticate"]
   end
 
   test "authentication request with invalid credential" do
-    @request.env['HTTP_AUTHORIZATION'] = encode_credentials('pretty', 'foo')
+    @request.env["HTTP_AUTHORIZATION"] = encode_credentials("pretty", "foo")
     get :display
 
     assert_response :unauthorized
     assert_equal "Authentication Failed\n", @response.body
-    assert_equal 'Basic realm="SuperSecret"', @response.headers['WWW-Authenticate']
+    assert_equal 'Basic realm="SuperSecret"', @response.headers["WWW-Authenticate"]
   end
 
   test "authentication request with valid credential" do
-    @request.env['HTTP_AUTHORIZATION'] = encode_credentials('pretty', 'please')
+    @request.env["HTTP_AUTHORIZATION"] = encode_credentials("pretty", "please")
     get :display
 
     assert_response :success
-    assert_equal 'Definitely Maybe', @response.body
+    assert_equal "Definitely Maybe", @response.body
   end
 
   test "authentication request with valid credential special chars" do
-    @request.env['HTTP_AUTHORIZATION'] = encode_credentials('login!@#$%^&*()_+{}[];"\',./<>?`~ \n\r\t', 'pwd:!@#$%^&*()_+{}[];"\',./<>?`~ \n\r\t')
+    @request.env["HTTP_AUTHORIZATION"] = encode_credentials('login!@#$%^&*()_+{}[];"\',./<>?`~ \n\r\t', 'pwd:!@#$%^&*()_+{}[];"\',./<>?`~ \n\r\t')
     get :special_creds
 
     assert_response :success
-    assert_equal 'Only for special credentials', @response.body
+    assert_equal "Only for special credentials", @response.body
   end
 
   test "authenticate with class method" do
-    @request.env['HTTP_AUTHORIZATION'] = encode_credentials('David', 'Goliath')
+    @request.env["HTTP_AUTHORIZATION"] = encode_credentials("David", "Goliath")
     get :search
     assert_response :success
 
-    @request.env['HTTP_AUTHORIZATION'] = encode_credentials('David', 'WRONG!')
+    @request.env["HTTP_AUTHORIZATION"] = encode_credentials("David", "WRONG!")
     get :search
     assert_response :unauthorized
   end
 
   test "authentication request with wrong scheme" do
-    header = 'Bearer ' + encode_credentials('David', 'Goliath').split(' ', 2)[1]
-    @request.env['HTTP_AUTHORIZATION'] = header
+    header = "Bearer " + encode_credentials("David", "Goliath").split(" ", 2)[1]
+    @request.env["HTTP_AUTHORIZATION"] = header
     get :search
     assert_response :unauthorized
   end
 
   private
 
-  def encode_credentials(username, password)
-    "Basic #{::Base64.encode64("#{username}:#{password}")}"
-  end
+    def encode_credentials(username, password)
+      "Basic #{::Base64.encode64("#{username}:#{password}")}"
+    end
 end
diff --git a/actionpack/test/controller/http_digest_authentication_test.rb b/actionpack/test/controller/http_digest_authentication_test.rb
index f06912bd5a..76ff784926 100644
--- a/actionpack/test/controller/http_digest_authentication_test.rb
+++ b/actionpack/test/controller/http_digest_authentication_test.rb
@@ -1,41 +1,43 @@
-require 'abstract_unit'
-require 'active_support/key_generator'
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "active_support/key_generator"
 
 class HttpDigestAuthenticationTest < ActionController::TestCase
   class DummyDigestController < ActionController::Base
     before_action :authenticate, only: :index
     before_action :authenticate_with_request, only: :display
 
-    USERS = { 'lifo' => 'world', 'pretty' => 'please',
-              'dhh' => ::Digest::MD5::hexdigest(["dhh","SuperSecret","secret"].join(":"))}
+    USERS = { "lifo" => "world", "pretty" => "please",
+              "dhh" => ::Digest::MD5::hexdigest(["dhh", "SuperSecret", "secret"].join(":")) }
 
     def index
       render plain: "Hello Secret"
     end
 
     def display
-      render plain: 'Definitely Maybe' if @logged_in
+      render plain: "Definitely Maybe" if @logged_in
     end
 
     private
 
-    def authenticate
-      authenticate_or_request_with_http_digest("SuperSecret") do |username|
-        # Returns the password
-        USERS[username]
+      def authenticate
+        authenticate_or_request_with_http_digest("SuperSecret") do |username|
+          # Returns the password
+          USERS[username]
+        end
       end
-    end
 
-    def authenticate_with_request
-      if authenticate_with_http_digest("SuperSecret")  { |username| USERS[username] }
-        @logged_in = true
-      else
-        request_http_digest_authentication("SuperSecret", "Authentication Failed")
+      def authenticate_with_request
+        if authenticate_with_http_digest("SuperSecret")  { |username| USERS[username] }
+          @logged_in = true
+        else
+          request_http_digest_authentication("SuperSecret", "Authentication Failed")
+        end
       end
-    end
   end
 
-  AUTH_HEADERS = ['HTTP_AUTHORIZATION', 'X-HTTP_AUTHORIZATION', 'X_HTTP_AUTHORIZATION', 'REDIRECT_X_HTTP_AUTHORIZATION']
+  AUTH_HEADERS = ["HTTP_AUTHORIZATION", "X-HTTP_AUTHORIZATION", "X_HTTP_AUTHORIZATION", "REDIRECT_X_HTTP_AUTHORIZATION"]
 
   tests DummyDigestController
 
@@ -51,17 +53,17 @@ class HttpDigestAuthenticationTest < ActionController::TestCase
 
   AUTH_HEADERS.each do |header|
     test "successful authentication with #{header.downcase}" do
-      @request.env[header] = encode_credentials(:username => 'lifo', :password => 'world')
+      @request.env[header] = encode_credentials(username: "lifo", password: "world")
       get :index
 
       assert_response :success
-      assert_equal 'Hello Secret', @response.body, "Authentication failed for request header #{header}"
+      assert_equal "Hello Secret", @response.body, "Authentication failed for request header #{header}"
     end
   end
 
   AUTH_HEADERS.each do |header|
     test "unsuccessful authentication with #{header.downcase}" do
-      @request.env[header] = encode_credentials(:username => 'h4x0r', :password => 'world')
+      @request.env[header] = encode_credentials(username: "h4x0r", password: "world")
       get :index
 
       assert_response :unauthorized
@@ -74,21 +76,21 @@ class HttpDigestAuthenticationTest < ActionController::TestCase
 
     assert_response :unauthorized
     assert_equal "Authentication Failed", @response.body
-    credentials = decode_credentials(@response.headers['WWW-Authenticate'])
-    assert_equal 'SuperSecret', credentials[:realm]
+    credentials = decode_credentials(@response.headers["WWW-Authenticate"])
+    assert_equal "SuperSecret", credentials[:realm]
   end
 
   test "authentication request with nil credentials" do
-    @request.env['HTTP_AUTHORIZATION'] = encode_credentials(:username => nil, :password => nil)
+    @request.env["HTTP_AUTHORIZATION"] = encode_credentials(username: nil, password: nil)
     get :index
 
     assert_response :unauthorized
     assert_equal "HTTP Digest: Access denied.\n", @response.body, "Authentication didn't fail for request"
-    assert_not_equal 'Hello Secret', @response.body, "Authentication didn't fail for request"
+    assert_not_equal "Hello Secret", @response.body, "Authentication didn't fail for request"
   end
 
   test "authentication request with invalid password" do
-    @request.env['HTTP_AUTHORIZATION'] = encode_credentials(:username => 'pretty', :password => 'foo')
+    @request.env["HTTP_AUTHORIZATION"] = encode_credentials(username: "pretty", password: "foo")
     get :display
 
     assert_response :unauthorized
@@ -96,7 +98,7 @@ class HttpDigestAuthenticationTest < ActionController::TestCase
   end
 
   test "authentication request with invalid nonce" do
-    @request.env['HTTP_AUTHORIZATION'] = encode_credentials(:username => 'pretty', :password => 'please', :nonce => "xxyyzz")
+    @request.env["HTTP_AUTHORIZATION"] = encode_credentials(username: "pretty", password: "please", nonce: "xxyyzz")
     get :display
 
     assert_response :unauthorized
@@ -104,7 +106,7 @@ class HttpDigestAuthenticationTest < ActionController::TestCase
   end
 
   test "authentication request with invalid opaque" do
-    @request.env['HTTP_AUTHORIZATION'] = encode_credentials(:username => 'pretty', :password => 'foo', :opaque => "xxyyzz")
+    @request.env["HTTP_AUTHORIZATION"] = encode_credentials(username: "pretty", password: "foo", opaque: "xxyyzz")
     get :display
 
     assert_response :unauthorized
@@ -112,7 +114,7 @@ class HttpDigestAuthenticationTest < ActionController::TestCase
   end
 
   test "authentication request with invalid realm" do
-    @request.env['HTTP_AUTHORIZATION'] = encode_credentials(:username => 'pretty', :password => 'foo', :realm => "NotSecret")
+    @request.env["HTTP_AUTHORIZATION"] = encode_credentials(username: "pretty", password: "foo", realm: "NotSecret")
     get :display
 
     assert_response :unauthorized
@@ -120,127 +122,127 @@ class HttpDigestAuthenticationTest < ActionController::TestCase
   end
 
   test "authentication request with valid credential" do
-    @request.env['HTTP_AUTHORIZATION'] = encode_credentials(:username => 'pretty', :password => 'please')
+    @request.env["HTTP_AUTHORIZATION"] = encode_credentials(username: "pretty", password: "please")
     get :display
 
     assert_response :success
-    assert_equal 'Definitely Maybe', @response.body
+    assert_equal "Definitely Maybe", @response.body
   end
 
   test "authentication request with valid credential and nil session" do
-    @request.env['HTTP_AUTHORIZATION'] = encode_credentials(:username => 'pretty', :password => 'please')
+    @request.env["HTTP_AUTHORIZATION"] = encode_credentials(username: "pretty", password: "please")
 
     get :display
 
     assert_response :success
-    assert_equal 'Definitely Maybe', @response.body
+    assert_equal "Definitely Maybe", @response.body
   end
 
   test "authentication request with request-uri that doesn't match credentials digest-uri" do
-    @request.env['HTTP_AUTHORIZATION'] = encode_credentials(:username => 'pretty', :password => 'please')
-    @request.env['PATH_INFO'] = "/proxied/uri"
+    @request.env["HTTP_AUTHORIZATION"] = encode_credentials(username: "pretty", password: "please")
+    @request.env["PATH_INFO"] = "/proxied/uri"
     get :display
 
     assert_response :success
-    assert_equal 'Definitely Maybe', @response.body
+    assert_equal "Definitely Maybe", @response.body
   end
 
   test "authentication request with absolute request uri (as in webrick)" do
-    @request.env['HTTP_AUTHORIZATION'] = encode_credentials(:username => 'pretty', :password => 'please')
+    @request.env["HTTP_AUTHORIZATION"] = encode_credentials(username: "pretty", password: "please")
     @request.env["SERVER_NAME"] = "test.host"
-    @request.env['PATH_INFO'] = "/http_digest_authentication_test/dummy_digest"
+    @request.env["PATH_INFO"] = "/http_digest_authentication_test/dummy_digest"
 
     get :display
 
     assert_response :success
-    assert_equal 'Definitely Maybe', @response.body
+    assert_equal "Definitely Maybe", @response.body
   end
 
   test "authentication request with absolute uri in credentials (as in IE)" do
-    @request.env['HTTP_AUTHORIZATION'] = encode_credentials(:url => "http://test.host/http_digest_authentication_test/dummy_digest",
-                                                            :username => 'pretty', :password => 'please')
+    @request.env["HTTP_AUTHORIZATION"] = encode_credentials(url: "http://test.host/http_digest_authentication_test/dummy_digest",
+                                                            username: "pretty", password: "please")
 
     get :display
 
     assert_response :success
-    assert_equal 'Definitely Maybe', @response.body
+    assert_equal "Definitely Maybe", @response.body
   end
 
   test "authentication request with absolute uri in both request and credentials (as in Webrick with IE)" do
-    @request.env['HTTP_AUTHORIZATION'] = encode_credentials(:url => "http://test.host/http_digest_authentication_test/dummy_digest",
-                                                            :username => 'pretty', :password => 'please')
-    @request.env['SERVER_NAME'] = "test.host"
-    @request.env['PATH_INFO'] = "/http_digest_authentication_test/dummy_digest"
+    @request.env["HTTP_AUTHORIZATION"] = encode_credentials(url: "http://test.host/http_digest_authentication_test/dummy_digest",
+                                                            username: "pretty", password: "please")
+    @request.env["SERVER_NAME"] = "test.host"
+    @request.env["PATH_INFO"] = "/http_digest_authentication_test/dummy_digest"
 
     get :display
 
     assert_response :success
-    assert_equal 'Definitely Maybe', @response.body
+    assert_equal "Definitely Maybe", @response.body
   end
 
   test "authentication request with password stored as ha1 digest hash" do
-    @request.env['HTTP_AUTHORIZATION'] = encode_credentials(:username => 'dhh',
-                                           :password => ::Digest::MD5::hexdigest(["dhh","SuperSecret","secret"].join(":")),
-                                           :password_is_ha1 => true)
+    @request.env["HTTP_AUTHORIZATION"] = encode_credentials(username: "dhh",
+                                           password: ::Digest::MD5::hexdigest(["dhh", "SuperSecret", "secret"].join(":")),
+                                           password_is_ha1: true)
     get :display
 
     assert_response :success
-    assert_equal 'Definitely Maybe', @response.body
+    assert_equal "Definitely Maybe", @response.body
   end
 
   test "authentication request with _method" do
-    @request.env['HTTP_AUTHORIZATION'] = encode_credentials(:username => 'pretty', :password => 'please', :method => :post)
-    @request.env['rack.methodoverride.original_method'] = 'POST'
+    @request.env["HTTP_AUTHORIZATION"] = encode_credentials(username: "pretty", password: "please", method: :post)
+    @request.env["rack.methodoverride.original_method"] = "POST"
     put :display
 
     assert_response :success
-    assert_equal 'Definitely Maybe', @response.body
+    assert_equal "Definitely Maybe", @response.body
   end
 
   test "validate_digest_response should fail with nil returning password_procedure" do
-    @request.env['HTTP_AUTHORIZATION'] = encode_credentials(:username => nil, :password => nil)
-    assert !ActionController::HttpAuthentication::Digest.validate_digest_response(@request, "SuperSecret"){nil}
+    @request.env["HTTP_AUTHORIZATION"] = encode_credentials(username: nil, password: nil)
+    assert !ActionController::HttpAuthentication::Digest.validate_digest_response(@request, "SuperSecret") { nil }
   end
 
   test "authentication request with request-uri ending in '/'" do
-    @request.env['PATH_INFO'] = "/http_digest_authentication_test/dummy_digest/"
-    @request.env['HTTP_AUTHORIZATION'] = encode_credentials(:username => 'pretty', :password => 'please')
+    @request.env["PATH_INFO"] = "/http_digest_authentication_test/dummy_digest/"
+    @request.env["HTTP_AUTHORIZATION"] = encode_credentials(username: "pretty", password: "please")
 
     # simulate normalizing PATH_INFO
-    @request.env['PATH_INFO'] = "/http_digest_authentication_test/dummy_digest"
+    @request.env["PATH_INFO"] = "/http_digest_authentication_test/dummy_digest"
     get :display
 
     assert_response :success
-    assert_equal 'Definitely Maybe', @response.body
+    assert_equal "Definitely Maybe", @response.body
   end
 
   test "authentication request with request-uri ending in '?'" do
-    @request.env['PATH_INFO'] = "/http_digest_authentication_test/dummy_digest/?"
-    @request.env['HTTP_AUTHORIZATION'] = encode_credentials(:username => 'pretty', :password => 'please')
+    @request.env["PATH_INFO"] = "/http_digest_authentication_test/dummy_digest/?"
+    @request.env["HTTP_AUTHORIZATION"] = encode_credentials(username: "pretty", password: "please")
 
     # simulate normalizing PATH_INFO
-    @request.env['PATH_INFO'] = "/http_digest_authentication_test/dummy_digest"
+    @request.env["PATH_INFO"] = "/http_digest_authentication_test/dummy_digest"
     get :display
 
     assert_response :success
-    assert_equal 'Definitely Maybe', @response.body
+    assert_equal "Definitely Maybe", @response.body
   end
 
   test "authentication request with absolute uri in credentials (as in IE) ending with /" do
-    @request.env['PATH_INFO'] = "/http_digest_authentication_test/dummy_digest/"
-    @request.env['HTTP_AUTHORIZATION'] = encode_credentials(:uri => "http://test.host/http_digest_authentication_test/dummy_digest/",
-                                                            :username => 'pretty', :password => 'please')
+    @request.env["PATH_INFO"] = "/http_digest_authentication_test/dummy_digest/"
+    @request.env["HTTP_AUTHORIZATION"] = encode_credentials(uri: "http://test.host/http_digest_authentication_test/dummy_digest/",
+                                                            username: "pretty", password: "please")
 
     # simulate normalizing PATH_INFO
-    @request.env['PATH_INFO'] = "/http_digest_authentication_test/dummy_digest"
+    @request.env["PATH_INFO"] = "/http_digest_authentication_test/dummy_digest"
     get :display
 
     assert_response :success
-    assert_equal 'Definitely Maybe', @response.body
+    assert_equal "Definitely Maybe", @response.body
   end
 
   test "when sent a basic auth header, returns Unauthorized" do
-    @request.env['HTTP_AUTHORIZATION'] = 'Basic Gwf2aXq8ZLF3Hxq='
+    @request.env["HTTP_AUTHORIZATION"] = "Basic Gwf2aXq8ZLF3Hxq="
 
     get :display
 
@@ -249,32 +251,32 @@ class HttpDigestAuthenticationTest < ActionController::TestCase
 
   private
 
-  def encode_credentials(options)
-    options.reverse_merge!(:nc => "00000001", :cnonce => "0a4f113b", :password_is_ha1 => false)
-    password = options.delete(:password)
+    def encode_credentials(options)
+      options.reverse_merge!(nc: "00000001", cnonce: "0a4f113b", password_is_ha1: false)
+      password = options.delete(:password)
 
-    # Perform unauthenticated request to retrieve digest parameters to use on subsequent request
-    method = options.delete(:method) || 'GET'
+      # Perform unauthenticated request to retrieve digest parameters to use on subsequent request
+      method = options.delete(:method) || "GET"
 
-    case method.to_s.upcase
-    when 'GET'
-      get :index
-    when 'POST'
-      post :index
-    end
+      case method.to_s.upcase
+      when "GET"
+        get :index
+      when "POST"
+        post :index
+      end
 
-    assert_response :unauthorized
+      assert_response :unauthorized
 
-    credentials = decode_credentials(@response.headers['WWW-Authenticate'])
-    credentials.merge!(options)
-    path_info = @request.env['PATH_INFO'].to_s
-    uri = options[:uri] || path_info
-    credentials.merge!(:uri => uri)
-    @request.env["ORIGINAL_FULLPATH"] = path_info
-    ActionController::HttpAuthentication::Digest.encode_credentials(method, credentials, password, options[:password_is_ha1])
-  end
+      credentials = decode_credentials(@response.headers["WWW-Authenticate"])
+      credentials.merge!(options)
+      path_info = @request.env["PATH_INFO"].to_s
+      uri = options[:uri] || path_info
+      credentials.merge!(uri: uri)
+      @request.env["ORIGINAL_FULLPATH"] = path_info
+      ActionController::HttpAuthentication::Digest.encode_credentials(method, credentials, password, options[:password_is_ha1])
+    end
 
-  def decode_credentials(header)
-    ActionController::HttpAuthentication::Digest.decode_credentials(header)
-  end
+    def decode_credentials(header)
+      ActionController::HttpAuthentication::Digest.decode_credentials(header)
+    end
 end
diff --git a/actionpack/test/controller/http_token_authentication_test.rb b/actionpack/test/controller/http_token_authentication_test.rb
index 98e3c891a7..672aa1351c 100644
--- a/actionpack/test/controller/http_token_authentication_test.rb
+++ b/actionpack/test/controller/http_token_authentication_test.rb
@@ -1,4 +1,6 @@
-require 'abstract_unit'
+# frozen_string_literal: true
+
+require "abstract_unit"
 
 class HttpTokenAuthenticationTest < ActionController::TestCase
   class DummyController < ActionController::Base
@@ -11,67 +13,67 @@ class HttpTokenAuthenticationTest < ActionController::TestCase
     end
 
     def display
-      render plain: 'Definitely Maybe'
+      render plain: "Definitely Maybe"
     end
 
     def show
-      render plain: 'Only for loooooong credentials'
+      render plain: "Only for loooooong credentials"
     end
 
     private
 
-    def authenticate
-      authenticate_or_request_with_http_token do |token, _|
-        token == 'lifo'
+      def authenticate
+        authenticate_or_request_with_http_token do |token, _|
+          token == "lifo"
+        end
       end
-    end
 
-    def authenticate_with_request
-      if authenticate_with_http_token { |token, options| token == '"quote" pretty' && options[:algorithm] == 'test' }
-        @logged_in = true
-      else
-        request_http_token_authentication("SuperSecret", "Authentication Failed\n")
+      def authenticate_with_request
+        if authenticate_with_http_token { |token, options| token == '"quote" pretty' && options[:algorithm] == "test" }
+          @logged_in = true
+        else
+          request_http_token_authentication("SuperSecret", "Authentication Failed\n")
+        end
       end
-    end
 
-    def authenticate_long_credentials
-      authenticate_or_request_with_http_token do |token, options|
-        token == '1234567890123456789012345678901234567890' && options[:algorithm] == 'test'
+      def authenticate_long_credentials
+        authenticate_or_request_with_http_token do |token, options|
+          token == "1234567890123456789012345678901234567890" && options[:algorithm] == "test"
+        end
       end
-    end
   end
 
-  AUTH_HEADERS = ['HTTP_AUTHORIZATION', 'X-HTTP_AUTHORIZATION', 'X_HTTP_AUTHORIZATION', 'REDIRECT_X_HTTP_AUTHORIZATION']
+  AUTH_HEADERS = ["HTTP_AUTHORIZATION", "X-HTTP_AUTHORIZATION", "X_HTTP_AUTHORIZATION", "REDIRECT_X_HTTP_AUTHORIZATION"]
 
   tests DummyController
 
   AUTH_HEADERS.each do |header|
     test "successful authentication with #{header.downcase}" do
-      @request.env[header] = encode_credentials('lifo')
+      @request.env[header] = encode_credentials("lifo")
       get :index
 
       assert_response :success
-      assert_equal 'Hello Secret', @response.body, "Authentication failed for request header #{header}"
+      assert_equal "Hello Secret", @response.body, "Authentication failed for request header #{header}"
     end
     test "successful authentication with #{header.downcase} and long credentials" do
-      @request.env[header] = encode_credentials('1234567890123456789012345678901234567890', :algorithm => 'test')
+      @request.env[header] = encode_credentials("1234567890123456789012345678901234567890", algorithm: "test")
       get :show
 
       assert_response :success
-      assert_equal 'Only for loooooong credentials', @response.body, "Authentication failed for request header #{header} and long credentials"
+      assert_equal "Only for loooooong credentials", @response.body, "Authentication failed for request header #{header} and long credentials"
     end
   end
 
   AUTH_HEADERS.each do |header|
     test "unsuccessful authentication with #{header.downcase}" do
-      @request.env[header] = encode_credentials('h4x0r')
+      @request.env[header] = encode_credentials("h4x0r")
       get :index
 
       assert_response :unauthorized
       assert_equal "HTTP Token: Access denied.\n", @response.body, "Authentication didn't fail for request header #{header}"
     end
     test "unsuccessful authentication with #{header.downcase} and long credentials" do
-      @request.env[header] = encode_credentials('h4x0rh4x0rh4x0rh4x0rh4x0rh4x0rh4x0rh4x0r')
+      @request.env[header] = encode_credentials("h4x0rh4x0rh4x0rh4x0rh4x0rh4x0rh4x0rh4x0r")
       get :show
 
       assert_response :unauthorized
@@ -80,7 +82,7 @@ class HttpTokenAuthenticationTest < ActionController::TestCase
   end
 
   test "authentication request with badly formatted header" do
-    @request.env['HTTP_AUTHORIZATION'] = 'Token token$"lifo"'
+    @request.env["HTTP_AUTHORIZATION"] = 'Token token$"lifo"'
     get :index
 
     assert_response :unauthorized
@@ -88,18 +90,18 @@ class HttpTokenAuthenticationTest < ActionController::TestCase
   end
 
   test "successful authentication request with Bearer instead of Token" do
-    @request.env['HTTP_AUTHORIZATION'] = 'Bearer lifo'
+    @request.env["HTTP_AUTHORIZATION"] = "Bearer lifo"
     get :index
 
     assert_response :success
   end
 
   test "authentication request with tab in header" do
-    @request.env['HTTP_AUTHORIZATION'] = "Token\ttoken=\"lifo\""
+    @request.env["HTTP_AUTHORIZATION"] = "Token\ttoken=\"lifo\""
     get :index
 
     assert_response :success
-    assert_equal 'Hello Secret', @response.body
+    assert_equal "Hello Secret", @response.body
   end
 
   test "authentication request without credential" do
@@ -107,16 +109,16 @@ class HttpTokenAuthenticationTest < ActionController::TestCase
 
     assert_response :unauthorized
     assert_equal "Authentication Failed\n", @response.body
-    assert_equal 'Token realm="SuperSecret"', @response.headers['WWW-Authenticate']
+    assert_equal 'Token realm="SuperSecret"', @response.headers["WWW-Authenticate"]
   end
 
   test "authentication request with invalid credential" do
-    @request.env['HTTP_AUTHORIZATION'] = encode_credentials('"quote" pretty')
+    @request.env["HTTP_AUTHORIZATION"] = encode_credentials('"quote" pretty')
     get :display
 
     assert_response :unauthorized
     assert_equal "Authentication Failed\n", @response.body
-    assert_equal 'Token realm="SuperSecret"', @response.headers['WWW-Authenticate']
+    assert_equal 'Token realm="SuperSecret"', @response.headers["WWW-Authenticate"]
   end
 
   test "token_and_options returns correct token" do
@@ -127,7 +129,7 @@ class HttpTokenAuthenticationTest < ActionController::TestCase
   end
 
   test "token_and_options returns correct token with value after the equal sign" do
-    token = 'rcHu+=HzSFw89Ypyhn/896A==f34'
+    token = "rcHu+=HzSFw89Ypyhn/896A==f34"
     actual = ActionController::HttpAuthentication::Token.token_and_options(sample_request(token)).first
     expected = token
     assert_equal(expected, actual)
@@ -148,7 +150,7 @@ class HttpTokenAuthenticationTest < ActionController::TestCase
   end
 
   test "token_and_options returns empty string with empty token" do
-    token = ''
+    token = "".dup
     actual = ActionController::HttpAuthentication::Token.token_and_options(sample_request(token)).first
     expected = token
     assert_equal(expected, actual)
@@ -156,18 +158,17 @@ class HttpTokenAuthenticationTest < ActionController::TestCase
 
   test "token_and_options returns correct token with nounce option" do
     token = "rcHu+HzSFw89Ypyhn/896A="
-    nonce_hash = {nonce: "123abc"}
+    nonce_hash = { nonce: "123abc" }
     actual = ActionController::HttpAuthentication::Token.token_and_options(sample_request(token, nonce_hash))
     expected_token = token
-    expected_nonce = {"nonce" => nonce_hash[:nonce]}
+    expected_nonce = { "nonce" => nonce_hash[:nonce] }
     assert_equal(expected_token, actual.first)
     assert_equal(expected_nonce, actual.last)
   end
 
   test "token_and_options returns nil with no value after the equal sign" do
     actual = ActionController::HttpAuthentication::Token.token_and_options(malformed_request).first
-    expected = nil
-    assert_equal(expected, actual)
+    assert_nil actual
   end
 
   test "raw_params returns a tuple of two key value pair strings" do
@@ -190,7 +191,7 @@ class HttpTokenAuthenticationTest < ActionController::TestCase
 
   private
 
-    def sample_request(token, options = {nonce: "def"})
+    def sample_request(token, options = { nonce: "def" })
       authorization = options.inject([%{Token token="#{token}"}]) do |arr, (k, v)|
         arr << "#{k}=\"#{v}\""
       end.join(", ")
diff --git a/actionpack/test/controller/integration_test.rb b/actionpack/test/controller/integration_test.rb
index 34fb3b1003..fd1c5e693f 100644
--- a/actionpack/test/controller/integration_test.rb
+++ b/actionpack/test/controller/integration_test.rb
@@ -1,10 +1,12 @@
-require 'abstract_unit'
-require 'controller/fake_controllers'
-require 'rails/engine'
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "controller/fake_controllers"
+require "rails/engine"
 
 class SessionTest < ActiveSupport::TestCase
   StubApp = lambda { |env|
-    [200, {"Content-Type" => "text/html", "Content-Length" => "13"}, ["Hello, World!"]]
+    [200, { "Content-Type" => "text/html", "Content-Length" => "13" }, ["Hello, World!"]]
   }
 
   def setup
@@ -31,97 +33,8 @@ class SessionTest < ActiveSupport::TestCase
     end
   end
 
-  def test_request_via_redirect_uses_given_method
-    path = "/somepath"; args = {:id => '1'}; headers = {"X-Test-Header" => "testvalue"}
-    assert_called_with @session, :process, [:put, path, params: args, headers: headers] do
-      @session.stub :redirect?, false do
-        assert_deprecated { @session.request_via_redirect(:put, path, params: args, headers: headers) }
-      end
-    end
-  end
-
-  def test_deprecated_request_via_redirect_uses_given_method
-    path = "/somepath"; args = { id: '1' }; headers = { "X-Test-Header" => "testvalue" }
-    assert_called_with @session, :process, [:put, path, params: args, headers: headers] do
-      @session.stub :redirect?, false do
-        assert_deprecated { @session.request_via_redirect(:put, path, args, headers) }
-      end
-    end
-  end
-
-  def test_request_via_redirect_follows_redirects
-    path = "/somepath"; args = {:id => '1'}; headers = {"X-Test-Header" => "testvalue"}
-    value_series = [true, true, false]
-    assert_called @session, :follow_redirect!, times: 2 do
-      @session.stub :redirect?, ->{ value_series.shift } do
-        assert_deprecated { @session.request_via_redirect(:get, path, params: args, headers: headers) }
-      end
-    end
-  end
-
-  def test_request_via_redirect_returns_status
-    path = "/somepath"; args = {:id => '1'}; headers = {"X-Test-Header" => "testvalue"}
-    @session.stub :redirect?, false do
-      @session.stub :status, 200 do
-        assert_deprecated do
-          assert_equal 200, @session.request_via_redirect(:get, path, params: args, headers: headers)
-        end
-      end
-    end
-  end
-
-  def test_deprecated_get_via_redirect
-    path = "/somepath"; args = { id: '1' }; headers = { "X-Test-Header" => "testvalue" }
-
-    assert_called_with @session, :request_via_redirect, [:get, path, args, headers] do
-      assert_deprecated do
-        @session.get_via_redirect(path, args, headers)
-      end
-    end
-  end
-
-  def test_deprecated_post_via_redirect
-    path = "/somepath"; args = { id: '1' }; headers = { "X-Test-Header" => "testvalue" }
-
-    assert_called_with @session, :request_via_redirect, [:post, path, args, headers] do
-      assert_deprecated do
-        @session.post_via_redirect(path, args, headers)
-      end
-    end
-  end
-
-  def test_deprecated_patch_via_redirect
-    path = "/somepath"; args = { id: '1' }; headers = { "X-Test-Header" => "testvalue" }
-
-    assert_called_with @session, :request_via_redirect, [:patch, path, args, headers] do
-      assert_deprecated do
-        @session.patch_via_redirect(path, args, headers)
-      end
-    end
-  end
-
-  def test_deprecated_put_via_redirect
-    path = "/somepath"; args = { id: '1' }; headers = { "X-Test-Header" => "testvalue" }
-
-    assert_called_with @session, :request_via_redirect, [:put, path, args, headers] do
-      assert_deprecated do
-        @session.put_via_redirect(path, args, headers)
-      end
-    end
-  end
-
-  def test_deprecated_delete_via_redirect
-    path = "/somepath"; args = { id: '1' }; headers = { "X-Test-Header" => "testvalue" }
-
-    assert_called_with @session, :request_via_redirect, [:delete, path, args, headers] do
-      assert_deprecated do
-        @session.delete_via_redirect(path, args, headers)
-      end
-    end
-  end
-
   def test_get
-    path = "/index"; params = "blah"; headers = { location: 'blah' }
+    path = "/index"; params = "blah"; headers = { location: "blah" }
 
     assert_called_with @session, :process, [:get, path, params: params, headers: headers] do
       @session.get(path, params: params, headers: headers)
@@ -129,229 +42,88 @@ class SessionTest < ActiveSupport::TestCase
   end
 
   def test_get_with_env_and_headers
-    path = "/index"; params = "blah"; headers = { location: 'blah' }; env = { 'HTTP_X_REQUESTED_WITH' => 'XMLHttpRequest' }
+    path = "/index"; params = "blah"; headers = { location: "blah" }; env = { "HTTP_X_REQUESTED_WITH" => "XMLHttpRequest" }
     assert_called_with @session, :process, [:get, path, params: params, headers: headers, env: env] do
       @session.get(path, params: params, headers: headers, env: env)
     end
   end
 
-  def test_deprecated_get
-    path = "/index"; params = "blah"; headers = { location: 'blah' }
-
-    assert_called_with @session, :process, [:get, path, params: params, headers: headers] do
-      assert_deprecated {
-        @session.get(path, params, headers)
-      }
-    end
-  end
-
   def test_post
-    path = "/index"; params = "blah"; headers = { location: 'blah' }
-    assert_called_with @session, :process, [:post, path, params: params, headers: headers] do
-      assert_deprecated {
-        @session.post(path, params, headers)
-      }
-    end
-  end
-
-  def test_deprecated_post
-    path = "/index"; params = "blah"; headers = { location: 'blah' }
+    path = "/index"; params = "blah"; headers = { location: "blah" }
     assert_called_with @session, :process, [:post, path, params: params, headers: headers] do
       @session.post(path, params: params, headers: headers)
     end
   end
 
   def test_patch
-    path = "/index"; params = "blah"; headers = { location: 'blah' }
+    path = "/index"; params = "blah"; headers = { location: "blah" }
     assert_called_with @session, :process, [:patch, path, params: params, headers: headers] do
       @session.patch(path, params: params, headers: headers)
     end
   end
 
-  def test_deprecated_patch
-    path = "/index"; params = "blah"; headers = { location: 'blah' }
-    assert_called_with @session, :process, [:patch, path, params: params, headers: headers] do
-      assert_deprecated {
-        @session.patch(path, params, headers)
-      }
-    end
-  end
-
   def test_put
-    path = "/index"; params = "blah"; headers = { location: 'blah' }
+    path = "/index"; params = "blah"; headers = { location: "blah" }
     assert_called_with @session, :process, [:put, path, params: params, headers: headers] do
       @session.put(path, params: params, headers: headers)
     end
   end
 
-  def test_deprecated_put
-    path = "/index"; params = "blah"; headers = { location: 'blah' }
-    assert_called_with @session, :process, [:put, path, params: params, headers: headers] do
-      assert_deprecated {
-        @session.put(path, params, headers)
-      }
-    end
-  end
-
   def test_delete
-    path = "/index"; params = "blah"; headers = { location: 'blah' }
-    assert_called_with @session, :process, [:delete, path, params: params, headers: headers] do
-      assert_deprecated {
-        @session.delete(path,params,headers)
-      }
-    end
-  end
-
-  def test_deprecated_delete
-    path = "/index"; params = "blah"; headers = { location: 'blah' }
+    path = "/index"; params = "blah"; headers = { location: "blah" }
     assert_called_with @session, :process, [:delete, path, params: params, headers: headers] do
       @session.delete(path, params: params, headers: headers)
     end
   end
 
   def test_head
-    path = "/index"; params = "blah"; headers = { location: 'blah' }
+    path = "/index"; params = "blah"; headers = { location: "blah" }
     assert_called_with @session, :process, [:head, path, params: params, headers: headers] do
       @session.head(path, params: params, headers: headers)
     end
   end
 
-  def deprecated_test_head
-    path = "/index"; params = "blah"; headers = { location: 'blah' }
-    assert_called_with @session, :process, [:head, path, params: params, headers: headers] do
-      assert_deprecated {
-        @session.head(path, params, headers)
-      }
-    end
-  end
-
   def test_xml_http_request_get
-    path = "/index"; params = "blah"; headers = { location: 'blah' }
+    path = "/index"; params = "blah"; headers = { location: "blah" }
     assert_called_with @session, :process, [:get, path, params: params, headers: headers, xhr: true] do
       @session.get(path, params: params, headers: headers, xhr: true)
     end
   end
 
-  def test_deprecated_xml_http_request_get
-    path = "/index"; params = "blah"; headers = { location: 'blah' }
-    assert_called_with @session, :process, [:get, path, params: params, headers: headers, xhr: true] do
-      @session.get(path, params: params, headers: headers, xhr: true)
-    end
-  end
-
-  def test_deprecated_args_xml_http_request_get
-    path = "/index"; params = "blah"; headers = { location: 'blah' }
-    assert_called_with @session, :process, [:get, path, params: params, headers: headers, xhr: true] do
-      assert_deprecated(/xml_http_request/) {
-        @session.xml_http_request(:get, path, params, headers)
-      }
-    end
-  end
-
   def test_xml_http_request_post
-    path = "/index"; params = "blah"; headers = { location: 'blah' }
-    assert_called_with @session, :process, [:post, path, params: params, headers: headers, xhr: true] do
-      @session.post(path, params: params, headers: headers, xhr: true)
-    end
-  end
-
-  def test_deprecated_xml_http_request_post
-    path = "/index"; params = "blah"; headers = { location: 'blah' }
+    path = "/index"; params = "blah"; headers = { location: "blah" }
     assert_called_with @session, :process, [:post, path, params: params, headers: headers, xhr: true] do
       @session.post(path, params: params, headers: headers, xhr: true)
     end
   end
 
-  def test_deprecated_args_xml_http_request_post
-    path = "/index"; params = "blah"; headers = { location: 'blah' }
-    assert_called_with @session, :process, [:post, path, params: params, headers: headers, xhr: true] do
-      assert_deprecated(/xml_http_request/) { @session.xml_http_request(:post,path,params,headers) }
-    end
-  end
-
   def test_xml_http_request_patch
-    path = "/index"; params = "blah"; headers = { location: 'blah' }
+    path = "/index"; params = "blah"; headers = { location: "blah" }
     assert_called_with @session, :process, [:patch, path, params: params, headers: headers, xhr: true] do
       @session.patch(path, params: params, headers: headers, xhr: true)
     end
   end
 
-  def test_deprecated_xml_http_request_patch
-    path = "/index"; params = "blah"; headers = { location: 'blah' }
-    assert_called_with @session, :process, [:patch, path, params: params, headers: headers, xhr: true] do
-      @session.patch(path, params: params, headers: headers, xhr: true)
-    end
-  end
-
-  def test_deprecated_args_xml_http_request_patch
-    path = "/index"; params = "blah"; headers = { location: 'blah' }
-    assert_called_with @session, :process, [:patch, path, params: params, headers: headers, xhr: true] do
-      assert_deprecated(/xml_http_request/) { @session.xml_http_request(:patch,path,params,headers) }
-    end
-  end
-
   def test_xml_http_request_put
-    path = "/index"; params = "blah"; headers = { location: 'blah' }
-    assert_called_with @session, :process, [:put, path, params: params, headers: headers, xhr: true] do
-      @session.put(path, params: params, headers: headers, xhr: true)
-    end
-  end
-
-  def test_deprecated_xml_http_request_put
-    path = "/index"; params = "blah"; headers = { location: 'blah' }
+    path = "/index"; params = "blah"; headers = { location: "blah" }
     assert_called_with @session, :process, [:put, path, params: params, headers: headers, xhr: true] do
       @session.put(path, params: params, headers: headers, xhr: true)
     end
   end
 
-  def test_deprecated_args_xml_http_request_put
-    path = "/index"; params = "blah"; headers = { location: 'blah' }
-    assert_called_with @session, :process, [:put, path, params: params, headers: headers, xhr: true] do
-      assert_deprecated(/xml_http_request/) { @session.xml_http_request(:put, path, params, headers) }
-    end
-  end
-
   def test_xml_http_request_delete
-    path = "/index"; params = "blah"; headers = { location: 'blah' }
+    path = "/index"; params = "blah"; headers = { location: "blah" }
     assert_called_with @session, :process, [:delete, path, params: params, headers: headers, xhr: true] do
       @session.delete(path, params: params, headers: headers, xhr: true)
     end
   end
 
-  def test_deprecated_xml_http_request_delete
-    path = "/index"; params = "blah"; headers = { location: 'blah' }
-    assert_called_with @session, :process, [:delete, path, params: params, headers: headers, xhr: true] do
-      assert_deprecated { @session.xml_http_request(:delete, path, params: params, headers: headers) }
-    end
-  end
-
-  def test_deprecated_args_xml_http_request_delete
-    path = "/index"; params = "blah"; headers = { location: 'blah' }
-    assert_called_with @session, :process, [:delete, path, params: params, headers: headers, xhr: true] do
-      assert_deprecated(/xml_http_request/) { @session.xml_http_request(:delete, path, params, headers) }
-    end
-  end
-
   def test_xml_http_request_head
-    path = "/index"; params = "blah"; headers = { location: 'blah' }
+    path = "/index"; params = "blah"; headers = { location: "blah" }
     assert_called_with @session, :process, [:head, path, params: params, headers: headers, xhr: true] do
       @session.head(path, params: params, headers: headers, xhr: true)
     end
   end
-
-  def test_deprecated_xml_http_request_head
-    path = "/index"; params = "blah"; headers = { location: 'blah' }
-    assert_called_with @session, :process, [:head, path, params: params, headers: headers, xhr: true] do
-      assert_deprecated(/xml_http_request/) { @session.xml_http_request(:head, path, params: params, headers: headers) }
-    end
-  end
-
-  def test_deprecated_args_xml_http_request_head
-    path = "/index"; params = "blah"; headers = { location: 'blah' }
-    assert_called_with @session, :process, [:head, path, params: params, headers: headers, xhr: true] do
-      assert_deprecated { @session.xml_http_request(:head, path, params, headers) }
-    end
-  end
 end
 
 class IntegrationTestTest < ActiveSupport::TestCase
@@ -372,12 +144,12 @@ class IntegrationTestTest < ActiveSupport::TestCase
   def test_does_not_prevent_method_missing_passing_up_to_ancestors
     mixin = Module.new do
       def method_missing(name, *args)
-        name.to_s == 'foo' ? 'pass' : super
+        name.to_s == "foo" ? "pass" : super
       end
     end
-    @test.class.superclass.__send__(:include, mixin)
+    @test.class.superclass.include(mixin)
     begin
-      assert_equal 'pass', @test.foo
+      assert_equal "pass", @test.foo
     ensure
       # leave other tests as unaffected as possible
       mixin.__send__(:remove_method, :method_missing)
@@ -392,7 +164,7 @@ class IntegrationTestUsesCorrectClass < ActionDispatch::IntegrationTest
     reset!
 
     %w( get post head patch put delete ).each do |verb|
-      assert_nothing_raised { __send__(verb, '/') }
+      assert_nothing_raised { __send__(verb, "/") }
     end
   end
 end
@@ -403,9 +175,10 @@ class IntegrationProcessTest < ActionDispatch::IntegrationTest
       respond_to do |format|
         format.html { render plain: "OK", status: 200 }
         format.js { render plain: "JS OK", status: 200 }
-        format.xml { render :xml => "<root></root>", :status => 200 }
-        format.rss { render :xml => "<root></root>", :status => 200 }
-        format.atom { render :xml => "<root></root>", :status => 200 }
+        format.json { render json: "JSON OK", status: 200 }
+        format.xml { render xml: "<root></root>", status: 200 }
+        format.rss { render xml: "<root></root>", status: 200 }
+        format.atom { render xml: "<root></root>", status: 200 }
       end
     end
 
@@ -428,7 +201,7 @@ class IntegrationProcessTest < ActionDispatch::IntegrationTest
     end
 
     def set_cookie
-      cookies["foo"] = 'bar'
+      cookies["foo"] = "bar"
       head :ok
     end
 
@@ -437,18 +210,18 @@ class IntegrationProcessTest < ActionDispatch::IntegrationTest
     end
 
     def redirect
-      redirect_to action_url('get')
+      redirect_to action_url("get")
     end
 
     def remove_header
       response.headers.delete params[:header]
-      head :ok, 'c' => '3'
+      head :ok, "c" => "3"
     end
   end
 
   def test_get
     with_test_route_set do
-      get '/get'
+      get "/get"
       assert_equal 200, status
       assert_equal "OK", status_message
       assert_response 200
@@ -465,7 +238,7 @@ class IntegrationProcessTest < ActionDispatch::IntegrationTest
   def test_get_xml_rss_atom
     %w[ application/xml application/rss+xml application/atom+xml ].each do |mime_string|
       with_test_route_set do
-        get "/get", headers: {"HTTP_ACCEPT" => mime_string}
+        get "/get", headers: { "HTTP_ACCEPT" => mime_string }
         assert_equal 200, status
         assert_equal "OK", status_message
         assert_response 200
@@ -482,7 +255,7 @@ class IntegrationProcessTest < ActionDispatch::IntegrationTest
 
   def test_post
     with_test_route_set do
-      post '/post'
+      post "/post"
       assert_equal 201, status
       assert_equal "Created", status_message
       assert_response 201
@@ -496,55 +269,55 @@ class IntegrationProcessTest < ActionDispatch::IntegrationTest
     end
   end
 
-  test 'response cookies are added to the cookie jar for the next request' do
+  test "response cookies are added to the cookie jar for the next request" do
     with_test_route_set do
-      self.cookies['cookie_1'] = "sugar"
-      self.cookies['cookie_2'] = "oatmeal"
-      get '/cookie_monster'
+      cookies["cookie_1"] = "sugar"
+      cookies["cookie_2"] = "oatmeal"
+      get "/cookie_monster"
       assert_equal "cookie_1=; path=/\ncookie_3=chocolate; path=/", headers["Set-Cookie"]
-      assert_equal({"cookie_1"=>"", "cookie_2"=>"oatmeal", "cookie_3"=>"chocolate"}, cookies.to_hash)
+      assert_equal({ "cookie_1" => "", "cookie_2" => "oatmeal", "cookie_3" => "chocolate" }, cookies.to_hash)
     end
   end
 
-  test 'cookie persist to next request' do
+  test "cookie persist to next request" do
     with_test_route_set do
-      get '/set_cookie'
+      get "/set_cookie"
       assert_response :success
 
       assert_equal "foo=bar; path=/", headers["Set-Cookie"]
-      assert_equal({"foo"=>"bar"}, cookies.to_hash)
+      assert_equal({ "foo" => "bar" }, cookies.to_hash)
 
-      get '/get_cookie'
+      get "/get_cookie"
       assert_response :success
       assert_equal "bar", body
 
-      assert_equal nil, headers["Set-Cookie"]
-      assert_equal({"foo"=>"bar"}, cookies.to_hash)
+      assert_nil headers["Set-Cookie"]
+      assert_equal({ "foo" => "bar" }, cookies.to_hash)
     end
   end
 
-  test 'cookie persist to next request on another domain' do
+  test "cookie persist to next request on another domain" do
     with_test_route_set do
       host! "37s.backpack.test"
 
-      get '/set_cookie'
+      get "/set_cookie"
       assert_response :success
 
       assert_equal "foo=bar; path=/", headers["Set-Cookie"]
-      assert_equal({"foo"=>"bar"}, cookies.to_hash)
+      assert_equal({ "foo" => "bar" }, cookies.to_hash)
 
-      get '/get_cookie'
+      get "/get_cookie"
       assert_response :success
       assert_equal "bar", body
 
-      assert_equal nil, headers["Set-Cookie"]
-      assert_equal({"foo"=>"bar"}, cookies.to_hash)
+      assert_nil headers["Set-Cookie"]
+      assert_equal({ "foo" => "bar" }, cookies.to_hash)
     end
   end
 
   def test_redirect
     with_test_route_set do
-      get '/redirect'
+      get "/redirect"
       assert_equal 302, status
       assert_equal "Found", status_message
       assert_response 302
@@ -558,27 +331,27 @@ class IntegrationProcessTest < ActionDispatch::IntegrationTest
       assert_response :success
       assert_equal "/get", path
 
-      get '/moved'
+      get "/moved"
       assert_response :redirect
-      assert_redirected_to '/method'
+      assert_redirected_to "/method"
     end
   end
 
-  def test_xml_http_request_get
+  def test_redirect_reset_html_document
     with_test_route_set do
-      get '/get', xhr: true
-      assert_equal 200, status
-      assert_equal "OK", status_message
-      assert_response 200
-      assert_response :success
+      get "/redirect"
+      previous_html_document = html_document
+
+      follow_redirect!
+
       assert_response :ok
-      assert_equal "JS OK", response.body
+      refute_same previous_html_document, html_document
     end
   end
 
-  def test_deprecated_xml_http_request_get
+  def test_xml_http_request_get
     with_test_route_set do
-      assert_deprecated { xhr :get, '/get' }
+      get "/get", xhr: true
       assert_equal 200, status
       assert_equal "OK", status_message
       assert_response 200
@@ -590,21 +363,29 @@ class IntegrationProcessTest < ActionDispatch::IntegrationTest
 
   def test_request_with_bad_format
     with_test_route_set do
-      get '/get.php', xhr: true
+      get "/get.php", xhr: true
       assert_equal 406, status
       assert_response 406
       assert_response :not_acceptable
     end
   end
 
+  test "creation of multiple integration sessions" do
+    integration_session # initialize first session
+    a = open_session
+    b = open_session
+
+    refute_same(a.integration_session, b.integration_session)
+  end
+
   def test_get_with_query_string
     with_test_route_set do
-      get '/get_with_params?foo=bar'
-      assert_equal '/get_with_params?foo=bar', request.env["REQUEST_URI"]
-      assert_equal '/get_with_params?foo=bar', request.fullpath
+      get "/get_with_params?foo=bar"
+      assert_equal "/get_with_params?foo=bar", request.env["REQUEST_URI"]
+      assert_equal "/get_with_params?foo=bar", request.fullpath
       assert_equal "foo=bar", request.env["QUERY_STRING"]
-      assert_equal 'foo=bar', request.query_string
-      assert_equal 'bar', request.parameters['foo']
+      assert_equal "foo=bar", request.query_string
+      assert_equal "bar", request.parameters["foo"]
 
       assert_equal 200, status
       assert_equal "foo: bar", response.body
@@ -613,77 +394,91 @@ class IntegrationProcessTest < ActionDispatch::IntegrationTest
 
   def test_get_with_parameters
     with_test_route_set do
-      get '/get_with_params', params: { foo: "bar" }
-      assert_equal '/get_with_params', request.env["PATH_INFO"]
-      assert_equal '/get_with_params', request.path_info
-      assert_equal 'foo=bar', request.env["QUERY_STRING"]
-      assert_equal 'foo=bar', request.query_string
-      assert_equal 'bar', request.parameters['foo']
+      get "/get_with_params", params: { foo: "bar" }
+      assert_equal "/get_with_params", request.env["PATH_INFO"]
+      assert_equal "/get_with_params", request.path_info
+      assert_equal "foo=bar", request.env["QUERY_STRING"]
+      assert_equal "foo=bar", request.query_string
+      assert_equal "bar", request.parameters["foo"]
 
       assert_equal 200, status
       assert_equal "foo: bar", response.body
     end
   end
 
+  def test_post_then_get_with_parameters_do_not_leak_across_requests
+    with_test_route_set do
+      post "/post", params: { leaks: "does-leak?" }
+
+      get "/get_with_params", params: { foo: "bar" }
+
+      assert request.env["rack.input"].string.empty?
+      assert_equal "foo=bar", request.env["QUERY_STRING"]
+      assert_equal "foo=bar", request.query_string
+      assert_equal "bar", request.parameters["foo"]
+      assert request.parameters["leaks"].nil?
+    end
+  end
+
   def test_head
     with_test_route_set do
-      head '/get'
+      head "/get"
       assert_equal 200, status
       assert_equal "", body
 
-      head '/post'
+      head "/post"
       assert_equal 201, status
       assert_equal "", body
 
-      get '/get/method'
+      get "/get/method"
       assert_equal 200, status
       assert_equal "method: get", body
 
-      head '/get/method'
+      head "/get/method"
       assert_equal 200, status
       assert_equal "", body
     end
   end
 
   def test_generate_url_with_controller
-    assert_equal 'http://www.example.com/foo', url_for(:controller => "foo")
+    assert_equal "http://www.example.com/foo", url_for(controller: "foo")
   end
 
   def test_port_via_host!
     with_test_route_set do
-      host! 'www.example.com:8080'
-      get '/get'
+      host! "www.example.com:8080"
+      get "/get"
       assert_equal 8080, request.port
     end
   end
 
   def test_port_via_process
     with_test_route_set do
-      get 'http://www.example.com:8080/get'
+      get "http://www.example.com:8080/get"
       assert_equal 8080, request.port
     end
   end
 
   def test_https_and_port_via_host_and_https!
     with_test_route_set do
-      host! 'www.example.com'
+      host! "www.example.com"
       https! true
 
-      get '/get'
+      get "/get"
       assert_equal 443, request.port
       assert_equal true, request.ssl?
 
-      host! 'www.example.com:443'
+      host! "www.example.com:443"
       https! true
 
-      get '/get'
+      get "/get"
       assert_equal 443, request.port
       assert_equal true, request.ssl?
 
-      host! 'www.example.com:8443'
+      host! "www.example.com:8443"
       https! true
 
-      get '/get'
+      get "/get"
       assert_equal 8443, request.port
       assert_equal true, request.ssl?
     end
@@ -691,11 +486,11 @@ class IntegrationProcessTest < ActionDispatch::IntegrationTest
 
   def test_https_and_port_via_process
     with_test_route_set do
-      get 'https://www.example.com/get'
+      get "https://www.example.com/get"
       assert_equal 443, request.port
       assert_equal true, request.ssl?
 
-      get 'https://www.example.com:8443/get'
+      get "https://www.example.com:8443/get"
       assert_equal 8443, request.port
       assert_equal true, request.ssl?
     end
@@ -703,14 +498,26 @@ class IntegrationProcessTest < ActionDispatch::IntegrationTest
 
   def test_respect_removal_of_default_headers_by_a_controller_action
     with_test_route_set do
-      with_default_headers 'a' => '1', 'b' => '2' do
-        get '/remove_header', params: { header: 'a' }
+      with_default_headers "a" => "1", "b" => "2" do
+        get "/remove_header", params: { header: "a" }
       end
     end
 
-    assert_not_includes @response.headers, 'a', 'Response should not include default header removed by the controller action'
-    assert_includes @response.headers, 'b'
-    assert_includes @response.headers, 'c'
+    assert_not_includes @response.headers, "a", "Response should not include default header removed by the controller action"
+    assert_includes @response.headers, "b"
+    assert_includes @response.headers, "c"
+  end
+
+  def test_accept_not_overridden_when_xhr_true
+    with_test_route_set do
+      get "/get", headers: { "Accept" => "application/json" }, xhr: true
+      assert_equal "application/json", request.accept
+      assert_equal "application/json", response.content_type
+
+      get "/get", headers: { "HTTP_ACCEPT" => "application/json" }, xhr: true
+      assert_equal "application/json", request.accept
+      assert_equal "application/json", response.content_type
+    end
   end
 
   private
@@ -730,15 +537,15 @@ class IntegrationProcessTest < ActionDispatch::IntegrationTest
         end
 
         set.draw do
-          get 'moved' => redirect('/method')
+          get "moved" => redirect("/method")
 
           ActiveSupport::Deprecation.silence do
-            match ':action', :to => controller, :via => [:get, :post], :as => :action
-            get 'get/:action', :to => controller, :as => :get_action
+            match ":action", to: controller, via: [:get, :post], as: :action
+            get "get/:action", to: controller, as: :get_action
           end
         end
 
-        self.singleton_class.include(set.url_helpers)
+        singleton_class.include(set.url_helpers)
 
         yield
       end
@@ -751,9 +558,9 @@ class MetalIntegrationTest < ActionDispatch::IntegrationTest
   class Poller
     def self.call(env)
       if env["PATH_INFO"] =~ /^\/success/
-        [200, {"Content-Type" => "text/plain", "Content-Length" => "12"}, ["Hello World!"]]
+        [200, { "Content-Type" => "text/plain", "Content-Length" => "12" }, ["Hello World!"]]
       else
-        [404, {"Content-Type" => "text/plain", "Content-Length" => "0"}, []]
+        [404, { "Content-Type" => "text/plain", "Content-Length" => "0" }, []]
       end
     end
   end
@@ -774,15 +581,15 @@ class MetalIntegrationTest < ActionDispatch::IntegrationTest
     get "/failure"
     assert_response 404
     assert_response :not_found
-    assert_equal '', response.body
+    assert_equal "", response.body
   end
 
   def test_generate_url_without_controller
-    assert_equal 'http://www.example.com/foo', url_for(:controller => "foo")
+    assert_equal "http://www.example.com/foo", url_for(controller: "foo")
   end
 
   def test_pass_headers
-    get "/success", headers: {"Referer" => "http://www.example.com/foo", "Host" => "http://nohost.com"}
+    get "/success", headers: { "Referer" => "http://www.example.com/foo", "Host" => "http://nohost.com" }
 
     assert_equal "http://nohost.com", @request.env["HTTP_HOST"]
     assert_equal "http://www.example.com/foo", @request.env["HTTP_REFERER"]
@@ -821,7 +628,6 @@ class MetalIntegrationTest < ActionDispatch::IntegrationTest
     get "https://test.com:80"
     assert_equal "test.com:80", @request.env["HTTP_HOST"]
   end
-
 end
 
 class ApplicationIntegrationTest < ActionDispatch::IntegrationTest
@@ -845,7 +651,7 @@ class ApplicationIntegrationTest < ActionDispatch::IntegrationTest
     end
 
     routes.draw do
-      get 'baz', :to => 'application_integration_test/test#index', :as => :baz
+      get "baz", to: "application_integration_test/test#index", as: :baz
     end
 
     def self.call(*)
@@ -853,14 +659,14 @@ class ApplicationIntegrationTest < ActionDispatch::IntegrationTest
   end
 
   routes.draw do
-    get '',    :to => 'application_integration_test/test#index', :as => :empty_string
+    get "",    to: "application_integration_test/test#index", as: :empty_string
 
-    get 'foo', :to => 'application_integration_test/test#index', :as => :foo
-    get 'bar', :to => 'application_integration_test/test#index', :as => :bar
+    get "foo", to: "application_integration_test/test#index", as: :foo
+    get "bar", to: "application_integration_test/test#index", as: :bar
 
-    mount MountedApp => '/mounted', :as => "mounted"
-    get 'fooz' => proc { |env| [ 200, {'X-Cascade' => 'pass'}, [ "omg" ] ] }, :anchor => false
-    get 'fooz', :to => 'application_integration_test/test#index'
+    mount MountedApp => "/mounted", :as => "mounted"
+    get "fooz" => proc { |env| [ 200, { "X-Cascade" => "pass" }, [ "omg" ] ] }, :anchor => false
+    get "fooz", to: "application_integration_test/test#index"
   end
 
   def app
@@ -868,30 +674,30 @@ class ApplicationIntegrationTest < ActionDispatch::IntegrationTest
   end
 
   test "includes route helpers" do
-    assert_equal '/', empty_string_path
-    assert_equal '/foo', foo_path
-    assert_equal '/bar', bar_path
+    assert_equal "/", empty_string_path
+    assert_equal "/foo", foo_path
+    assert_equal "/bar", bar_path
   end
 
   test "includes mounted helpers" do
-    assert_equal '/mounted/baz', mounted.baz_path
+    assert_equal "/mounted/baz", mounted.baz_path
   end
 
   test "path after cascade pass" do
-    get '/fooz'
-    assert_equal 'index', response.body
-    assert_equal '/fooz', path
+    get "/fooz"
+    assert_equal "index", response.body
+    assert_equal "/fooz", path
   end
 
   test "route helpers after controller access" do
-    get '/'
-    assert_equal '/', empty_string_path
+    get "/"
+    assert_equal "/", empty_string_path
 
-    get '/foo'
-    assert_equal '/foo', foo_path
+    get "/foo"
+    assert_equal "/foo", foo_path
 
-    get '/bar'
-    assert_equal '/bar', bar_path
+    get "/bar"
+    assert_equal "/bar", bar_path
   end
 
   test "missing route helper before controller access" do
@@ -899,14 +705,14 @@ class ApplicationIntegrationTest < ActionDispatch::IntegrationTest
   end
 
   test "missing route helper after controller access" do
-    get '/foo'
+    get "/foo"
     assert_raise(NameError) { missing_path }
   end
 
   test "process do not modify the env passed as argument" do
-    env = { :SERVER_NAME => 'server', 'action_dispatch.custom' => 'custom' }
+    env = { :SERVER_NAME => "server", "action_dispatch.custom" => "custom" }
     old_env = env.dup
-    get '/foo', env: env
+    get "/foo", env: env
     assert_equal old_env, env
   end
 end
@@ -928,7 +734,7 @@ class EnvironmentFilterIntegrationTest < ActionDispatch::IntegrationTest
   end
 
   routes.draw do
-    match '/post', :to => 'environment_filter_integration_test/test#post', :via => :post
+    match "/post", to: "environment_filter_integration_test/test#post", via: :post
   end
 
   def app
@@ -936,11 +742,11 @@ class EnvironmentFilterIntegrationTest < ActionDispatch::IntegrationTest
   end
 
   test "filters rack request form vars" do
-    post "/post", params: { username: 'cjolly', password: 'secret' }
+    post "/post", params: { username: "cjolly", password: "secret" }
 
-    assert_equal 'cjolly', request.filtered_parameters['username']
-    assert_equal '[FILTERED]', request.filtered_parameters['password']
-    assert_equal '[FILTERED]', request.filtered_env['rack.request.form_vars']
+    assert_equal "cjolly", request.filtered_parameters["username"]
+    assert_equal "[FILTERED]", request.filtered_parameters["password"]
+    assert_equal "[FILTERED]", request.filtered_env["rack.request.form_vars"]
   end
 end
 
@@ -961,7 +767,7 @@ class UrlOptionsIntegrationTest < ActionDispatch::IntegrationTest
 
   class BarController < ActionController::Base
     def default_url_options
-      { :host => "bar.com" }
+      { host: "bar.com" }
     end
 
     def index
@@ -982,9 +788,9 @@ class UrlOptionsIntegrationTest < ActionDispatch::IntegrationTest
   end
 
   routes.draw do
-    default_url_options :host => "foo.com"
+    default_url_options host: "foo.com"
 
-    scope :module => "url_options_integration_test" do
+    scope module: "url_options_integration_test" do
       get "/foo" => "foo#index", :as => :foos
       get "/foo/:id" => "foo#show", :as => :foo
       get "/foo/:id/edit" => "foo#edit", :as => :edit_foo
@@ -1024,7 +830,7 @@ class UrlOptionsIntegrationTest < ActionDispatch::IntegrationTest
   test "current request path parameters are recalled" do
     get "/foo/1"
     assert_response :success
-    assert_equal "/foo/1/edit", url_for(:action => 'edit', :only_path => true)
+    assert_equal "/foo/1/edit", url_for(action: "edit", only_path: true)
   end
 end
 
@@ -1048,12 +854,12 @@ class HeadWithStatusActionIntegrationTest < ActionDispatch::IntegrationTest
   end
 
   routes.draw do
-    get "/foo/status" => 'head_with_status_action_integration_test/foo#status'
+    get "/foo/status" => "head_with_status_action_integration_test/foo#status"
   end
 
   test "get /foo/status with head result does not cause stack overflow error" do
     assert_nothing_raised do
-      get '/foo/status'
+      get "/foo/status"
     end
     assert_response :ok
   end
@@ -1062,7 +868,7 @@ end
 class IntegrationWithRoutingTest < ActionDispatch::IntegrationTest
   class FooController < ActionController::Base
     def index
-      render plain: 'ok'
+      render plain: "ok"
     end
   end
 
@@ -1072,25 +878,25 @@ class IntegrationWithRoutingTest < ActionDispatch::IntegrationTest
     with_routing do |routes|
       routes.draw do
         namespace klass_namespace do
-          resources :foo, path: '/with'
+          resources :foo, path: "/with"
         end
       end
 
-      get '/integration_with_routing_test/with'
+      get "/integration_with_routing_test/with"
       assert_response 200
-      assert_equal 'ok', response.body
+      assert_equal "ok", response.body
     end
 
     with_routing do |routes|
       routes.draw do
         namespace klass_namespace do
-          resources :foo, path: '/routing'
+          resources :foo, path: "/routing"
         end
       end
 
-      get '/integration_with_routing_test/routing'
+      get "/integration_with_routing_test/routing"
       assert_response 200
-      assert_equal 'ok', response.body
+      assert_equal "ok", response.body
     end
   end
 end
@@ -1102,8 +908,8 @@ class IntegrationRequestsWithoutSetup < ActionDispatch::IntegrationTest
 
   class FooController < ActionController::Base
     def ok
-      cookies[:key] = 'ok'
-      render plain: 'ok'
+      cookies[:key] = "ok"
+      render plain: "ok"
     end
   end
 
@@ -1111,15 +917,15 @@ class IntegrationRequestsWithoutSetup < ActionDispatch::IntegrationTest
     with_routing do |routes|
       routes.draw do
         ActiveSupport::Deprecation.silence do
-          get ':action' => FooController
+          get ":action" => FooController
         end
       end
 
-      get '/ok'
+      get "/ok"
 
       assert_response 200
-      assert_equal 'ok', response.body
-      assert_equal 'ok', cookies['key']
+      assert_equal "ok", response.body
+      assert_equal "ok", cookies["key"]
     end
   end
 end
@@ -1127,23 +933,27 @@ end
 # to ensure that session requirements in setup are persisted in the tests
 class IntegrationRequestsWithSessionSetup < ActionDispatch::IntegrationTest
   setup do
-    cookies['user_name'] = 'david'
+    cookies["user_name"] = "david"
   end
 
   def test_cookies_set_in_setup_are_persisted_through_the_session
     get "/foo"
-    assert_equal({"user_name"=>"david"}, cookies.to_hash)
+    assert_equal({ "user_name" => "david" }, cookies.to_hash)
   end
 end
 
 class IntegrationRequestEncodersTest < ActionDispatch::IntegrationTest
   class FooController < ActionController::Base
+    def foos
+      render plain: "ok"
+    end
+
     def foos_json
       render json: params.permit(:foo)
     end
 
     def foos_wibble
-      render plain: 'ok'
+      render plain: "ok"
     end
   end
 
@@ -1151,25 +961,42 @@ class IntegrationRequestEncodersTest < ActionDispatch::IntegrationTest
     with_routing do |routes|
       routes.draw do
         ActiveSupport::Deprecation.silence do
-          post ':action' => FooController
+          post ":action" => FooController
         end
       end
 
-      post '/foos_json.json', params: { foo: 'fighters' }.to_json,
-        headers: { 'Content-Type' => 'application/json' }
+      post "/foos_json.json", params: { foo: "fighters" }.to_json,
+        headers: { "Content-Type" => "application/json" }
 
       assert_response :success
-      assert_equal({ 'foo' => 'fighters' }, response.parsed_body)
+      assert_equal({ "foo" => "fighters" }, response.parsed_body)
     end
   end
 
   def test_encoding_as_json
     post_to_foos as: :json do
       assert_response :success
-      assert_match 'foos_json.json', request.path
-      assert_equal 'application/json', request.content_type
-      assert_equal({ 'foo' => 'fighters' }, request.request_parameters)
-      assert_equal({ 'foo' => 'fighters' }, response.parsed_body)
+      assert_equal "application/json", request.content_type
+      assert_equal "application/json", request.accepts.first.to_s
+      assert_equal :json, request.format.ref
+      assert_equal({ "foo" => "fighters" }, request.request_parameters)
+      assert_equal({ "foo" => "fighters" }, response.parsed_body)
+    end
+  end
+
+  def test_doesnt_mangle_request_path
+    with_routing do |routes|
+      routes.draw do
+        ActiveSupport::Deprecation.silence do
+          post ":action" => FooController
+        end
+      end
+
+      post "/foos"
+      assert_equal "/foos", request.path
+
+      post "/foos_json", as: :json
+      assert_equal "/foos_json", request.path
     end
   end
 
@@ -1180,17 +1007,19 @@ class IntegrationRequestEncodersTest < ActionDispatch::IntegrationTest
   end
 
   def test_registering_custom_encoder
-    Mime::Type.register 'text/wibble', :wibble
+    Mime::Type.register "text/wibble", :wibble
 
     ActionDispatch::IntegrationTest.register_encoder(:wibble,
       param_encoder: -> params { params })
 
     post_to_foos as: :wibble do
       assert_response :success
-      assert_match 'foos_wibble.wibble', request.path
-      assert_equal 'text/wibble', request.content_type
+      assert_equal "/foos_wibble", request.path
+      assert_equal "text/wibble", request.content_type
+      assert_equal "text/wibble", request.accepts.first.to_s
+      assert_equal :wibble, request.format.ref
       assert_equal Hash.new, request.request_parameters # Unregistered MIME Type can't be parsed.
-      assert_equal 'ok', response.parsed_body
+      assert_equal "ok", response.parsed_body
     end
   ensure
     Mime::Type.unregister :wibble
@@ -1200,13 +1029,43 @@ class IntegrationRequestEncodersTest < ActionDispatch::IntegrationTest
     with_routing do |routes|
       routes.draw do
         ActiveSupport::Deprecation.silence do
-          get ':action' => FooController
+          get ":action" => FooController
         end
       end
 
-      get '/foos_json.json', params: { foo: 'heyo' }
+      get "/foos_json.json", params: { foo: "heyo" }
 
-      assert_equal({ 'foo' => 'heyo' }, response.parsed_body)
+      assert_equal({ "foo" => "heyo" }, response.parsed_body)
+    end
+  end
+
+  def test_get_parameters_with_as_option
+    with_routing do |routes|
+      routes.draw do
+        ActiveSupport::Deprecation.silence do
+          get ":action" => FooController
+        end
+      end
+
+      get "/foos_json?foo=heyo", as: :json
+
+      assert_equal({ "foo" => "heyo" }, response.parsed_body)
+    end
+  end
+
+  def test_get_request_with_json_uses_method_override_and_sends_a_post_request
+    with_routing do |routes|
+      routes.draw do
+        ActiveSupport::Deprecation.silence do
+          get ":action" => FooController
+        end
+      end
+
+      get "/foos_json", params: { foo: "heyo" }, as: :json
+
+      assert_equal "POST", request.method
+      assert_equal "GET", request.headers["X-Http-Method-Override"]
+      assert_equal({ "foo" => "heyo" }, response.parsed_body)
     end
   end
 
@@ -1215,13 +1074,49 @@ class IntegrationRequestEncodersTest < ActionDispatch::IntegrationTest
       with_routing do |routes|
         routes.draw do
           ActiveSupport::Deprecation.silence do
-            post ':action' => FooController
+            post ":action" => FooController
           end
         end
 
-        post "/foos_#{as}", params: { foo: 'fighters' }, as: as
+        post "/foos_#{as}", params: { foo: "fighters" }, as: as
 
         yield
       end
     end
 end
+
+class IntegrationFileUploadTest < ActionDispatch::IntegrationTest
+  class IntegrationController < ActionController::Base
+    def test_file_upload
+      render plain: params[:file].size
+    end
+  end
+
+  def self.routes
+    @routes ||= ActionDispatch::Routing::RouteSet.new
+  end
+
+  def self.call(env)
+    routes.call(env)
+  end
+
+  def app
+    self.class
+  end
+
+  def self.fixture_path
+    File.expand_path("../fixtures/multipart", __dir__)
+  end
+
+  routes.draw do
+    post "test_file_upload", to: "integration_file_upload_test/integration#test_file_upload"
+  end
+
+  def test_fixture_file_upload
+    post "/test_file_upload",
+      params: {
+        file: fixture_file_upload("/ruby_on_rails.jpg", "image/jpg")
+      }
+    assert_equal "45142", @response.body
+  end
+end
diff --git a/actionpack/test/controller/live_stream_test.rb b/actionpack/test/controller/live_stream_test.rb
index 5977124594..431fe90b23 100644
--- a/actionpack/test/controller/live_stream_test.rb
+++ b/actionpack/test/controller/live_stream_test.rb
@@ -1,5 +1,8 @@
-require 'abstract_unit'
-require 'concurrent/atomic/count_down_latch'
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "timeout"
+require "concurrent/atomic/count_down_latch"
 Thread.abort_on_exception = true
 
 module ActionController
@@ -8,10 +11,10 @@ module ActionController
       include ActionController::Live
 
       def basic_sse
-        response.headers['Content-Type'] = 'text/event-stream'
+        response.headers["Content-Type"] = "text/event-stream"
         sse = SSE.new(response.stream)
         sse.write("{\"name\":\"John\"}")
-        sse.write({ name: "Ryan" })
+        sse.write(name: "Ryan")
       ensure
         sse.close
       end
@@ -19,7 +22,7 @@ module ActionController
       def sse_with_event
         sse = SSE.new(response.stream, event: "send-name")
         sse.write("{\"name\":\"John\"}")
-        sse.write({ name: "Ryan" })
+        sse.write(name: "Ryan")
       ensure
         sse.close
       end
@@ -27,7 +30,7 @@ module ActionController
       def sse_with_retry
         sse = SSE.new(response.stream, retry: 1000)
         sse.write("{\"name\":\"John\"}")
-        sse.write({ name: "Ryan" }, retry: 1500)
+        sse.write({ name: "Ryan" }, { retry: 1500 })
       ensure
         sse.close
       end
@@ -35,7 +38,7 @@ module ActionController
       def sse_with_id
         sse = SSE.new(response.stream)
         sse.write("{\"name\":\"John\"}", id: 1)
-        sse.write({ name: "Ryan" }, id: 2)
+        sse.write({ name: "Ryan" }, { id: 2 })
       ensure
         sse.close
       end
@@ -115,7 +118,7 @@ module ActionController
       attr_accessor :latch, :tc, :error_latch
 
       def self.controller_path
-        'test'
+        "test"
       end
 
       def set_cookie
@@ -125,7 +128,7 @@ module ActionController
       end
 
       def render_text
-        render plain: 'zomg'
+        render plain: "zomg"
       end
 
       def default_header
@@ -134,7 +137,7 @@ module ActionController
       end
 
       def basic_stream
-        response.headers['Content-Type'] = 'text/event-stream'
+        response.headers["Content-Type"] = "text/event-stream"
         %w{ hello world }.each do |word|
           response.stream.write word
         end
@@ -142,7 +145,7 @@ module ActionController
       end
 
       def blocking_stream
-        response.headers['Content-Type'] = 'text/event-stream'
+        response.headers["Content-Type"] = "text/event-stream"
         %w{ hello world }.each do |word|
           response.stream.write word
           latch.wait
@@ -150,10 +153,26 @@ module ActionController
         response.stream.close
       end
 
+      def write_sleep_autoload
+        path = File.expand_path("../fixtures", __dir__)
+        ActiveSupport::Dependencies.autoload_paths << path
+
+        response.headers["Content-Type"] = "text/event-stream"
+        response.stream.write "before load"
+        sleep 0.01
+        silence_warning do
+          ::LoadMe
+        end
+        response.stream.close
+        latch.count_down
+
+        ActiveSupport::Dependencies.autoload_paths.reject! { |p| p == path }
+      end
+
       def thread_locals
-        tc.assert_equal 'aaron', Thread.current[:setting]
+        tc.assert_equal "aaron", Thread.current[:setting]
 
-        response.headers['Content-Type'] = 'text/event-stream'
+        response.headers["Content-Type"] = "text/event-stream"
         %w{ hello world }.each do |word|
           response.stream.write word
         end
@@ -161,20 +180,20 @@ module ActionController
       end
 
       def with_stale
-        render plain: 'stale' if stale?(etag: "123", template: false)
+        render plain: "stale" if stale?(etag: "123", template: false)
       end
 
       def exception_in_view
-        render 'doesntexist'
+        render "doesntexist"
       end
 
       def exception_in_view_after_commit
         response.stream.write ""
-        render 'doesntexist'
+        render "doesntexist"
       end
 
       def exception_with_callback
-        response.headers['Content-Type'] = 'text/event-stream'
+        response.headers["Content-Type"] = "text/event-stream"
 
         response.stream.on_error do
           response.stream.write %(data: "500 Internal Server Error"\n\n)
@@ -182,11 +201,11 @@ module ActionController
         end
 
         response.stream.write "" # make sure the response is committed
-        raise 'An exception occurred...'
+        raise "An exception occurred..."
       end
 
       def exception_in_controller
-        raise Exception, 'Exception in controller'
+        raise Exception, "Exception in controller"
       end
 
       def bad_request_error
@@ -194,50 +213,50 @@ module ActionController
       end
 
       def exception_in_exception_callback
-        response.headers['Content-Type'] = 'text/event-stream'
+        response.headers["Content-Type"] = "text/event-stream"
         response.stream.on_error do
-          raise 'We need to go deeper.'
+          raise "We need to go deeper."
         end
-        response.stream.write ''
+        response.stream.write ""
         response.stream.write params[:widget][:didnt_check_for_nil]
       end
 
       def overfill_buffer_and_die
         logger = ActionController::Base.logger || Logger.new($stdout)
         response.stream.on_error do
-          logger.warn 'Error while streaming.'
+          logger.warn "Error while streaming."
           error_latch.count_down
         end
 
         # Write until the buffer is full. It doesn't expose that
         # information directly, so we must hard-code its size:
         10.times do
-          response.stream.write '.'
+          response.stream.write "."
         end
         # .. plus one more, because the #each frees up a slot:
-        response.stream.write '.'
+        response.stream.write "."
 
         latch.count_down
 
         # This write will block, and eventually raise
-        response.stream.write 'x'
+        response.stream.write "x"
 
         20.times do
-          response.stream.write '.'
+          response.stream.write "."
         end
       end
 
       def ignore_client_disconnect
         response.stream.ignore_disconnect = true
 
-        response.stream.write '' # commit
+        response.stream.write "" # commit
 
         # These writes will be ignored
         15.times do
-          response.stream.write 'x'
+          response.stream.write "x"
         end
 
-        logger.info 'Work complete'
+        logger.info "Work complete"
         latch.count_down
       end
     end
@@ -245,9 +264,9 @@ module ActionController
     tests TestController
 
     def assert_stream_closed
-      assert response.stream.closed?, 'stream should be closed'
-      assert response.committed?,     'response should be committed'
-      assert response.sent?,          'response should be sent'
+      assert response.stream.closed?, "stream should be closed"
+      assert response.committed?,     "response should be committed"
+      assert response.sent?,          "response should be sent"
     end
 
     def capture_log_output
@@ -271,21 +290,29 @@ module ActionController
 
     def test_set_cookie
       get :set_cookie
-      assert_equal({'hello' => 'world'}, @response.cookies)
+      assert_equal({ "hello" => "world" }, @response.cookies)
       assert_equal "hello world", @response.body
     end
 
     def test_write_to_stream
       get :basic_stream
       assert_equal "helloworld", @response.body
-      assert_equal 'text/event-stream', @response.headers['Content-Type']
+      assert_equal "text/event-stream", @response.headers["Content-Type"]
+    end
+
+    def test_delayed_autoload_after_write_within_interlock_hook
+      # Simulate InterlockHook
+      ActiveSupport::Dependencies.interlock.start_running
+      res = get :write_sleep_autoload
+      res.each {}
+      ActiveSupport::Dependencies.interlock.done_running
     end
 
     def test_async_stream
       rubinius_skip "https://github.com/rubinius/rubinius/issues/2934"
 
       @controller.latch = Concurrent::CountDownLatch.new
-      parts             = ['hello', 'world']
+      parts             = ["hello", "world"]
 
       get :blocking_stream
 
@@ -299,7 +326,7 @@ module ActionController
         end
       }
 
-      assert t.join(3), 'timeout expired before the thread terminated'
+      assert t.join(3), "timeout expired before the thread terminated"
     end
 
     def test_abort_with_full_buffer
@@ -307,7 +334,7 @@ module ActionController
       @controller.error_latch = Concurrent::CountDownLatch.new
 
       capture_log_output do |output|
-        get :overfill_buffer_and_die, :format => 'plain'
+        get :overfill_buffer_and_die, format: "plain"
 
         t = Thread.new(response) { |resp|
           resp.await_commit
@@ -321,7 +348,7 @@ module ActionController
 
         t.join
         @controller.error_latch.wait
-        assert_match 'Error while streaming', output.rewind && output.read
+        assert_match "Error while streaming", output.rewind && output.read
       end
     end
 
@@ -344,26 +371,26 @@ module ActionController
         Timeout.timeout(3) do
           @controller.latch.wait
         end
-        assert_match 'Work complete', output.rewind && output.read
+        assert_match "Work complete", output.rewind && output.read
       end
     end
 
     def test_thread_locals_get_copied
       @controller.tc = self
       Thread.current[:originating_thread] = Thread.current.object_id
-      Thread.current[:setting]            = 'aaron'
+      Thread.current[:setting]            = "aaron"
 
       get :thread_locals
     end
 
     def test_live_stream_default_header
       get :default_header
-      assert response.headers['Content-Type']
+      assert response.headers["Content-Type"]
     end
 
     def test_render_text
       get :render_text
-      assert_equal 'zomg', response.body
+      assert_equal "zomg", response.body
       assert_stream_closed
     end
 
@@ -375,7 +402,7 @@ module ActionController
       capture_log_output do |output|
         get :exception_in_view_after_commit
         assert_match %r((window\.location = "/500\.html"</script></html>)$), response.body
-        assert_match 'Missing template test/doesntexist', output.rewind && output.read
+        assert_match "Missing template test/doesntexist", output.rewind && output.read
         assert_stream_closed
       end
       assert response.body
@@ -389,8 +416,8 @@ module ActionController
 
       capture_log_output do |output|
         get :exception_in_view_after_commit, format: :json
-        assert_equal '', response.body
-        assert_match 'Missing template test/doesntexist', output.rewind && output.read
+        assert_equal "", response.body
+        assert_match "Missing template test/doesntexist", output.rewind && output.read
         assert_stream_closed
       end
     end
@@ -399,34 +426,34 @@ module ActionController
       current_threads = Thread.list
 
       capture_log_output do |output|
-        get :exception_with_callback, format: 'text/event-stream'
+        get :exception_with_callback, format: "text/event-stream"
 
         # Wait on the execution of all threads
         (Thread.list - current_threads).each(&:join)
 
         assert_equal %(data: "500 Internal Server Error"\n\n), response.body
-        assert_match 'An exception occurred...', output.rewind && output.read
+        assert_match "An exception occurred...", output.rewind && output.read
         assert_stream_closed
       end
     end
 
     def test_exception_in_controller_before_streaming
       assert_raises(ActionController::LiveStreamTest::Exception) do
-        get :exception_in_controller, format: 'text/event-stream'
+        get :exception_in_controller, format: "text/event-stream"
       end
     end
 
     def test_bad_request_in_controller_before_streaming
       assert_raises(ActionController::BadRequest) do
-        get :bad_request_error, format: 'text/event-stream'
+        get :bad_request_error, format: "text/event-stream"
       end
     end
 
     def test_exceptions_raised_handling_exceptions_and_committed
       capture_log_output do |output|
-        get :exception_in_exception_callback, format: 'text/event-stream'
-        assert_equal '', response.body
-        assert_match 'We need to go deeper', output.rewind && output.read
+        get :exception_in_exception_callback, format: "text/event-stream"
+        assert_equal "", response.body
+        assert_match "We need to go deeper", output.rewind && output.read
         assert_stream_closed
       end
     end
@@ -437,7 +464,7 @@ module ActionController
     end
 
     def test_stale_with_etag
-      @request.if_none_match = %(W/"#{Digest::MD5.hexdigest('123')}")
+      @request.if_none_match = %(W/"#{ActiveSupport::Digest.hexdigest('123')}")
       get :with_stale
       assert_equal 304, response.status.to_i
     end
@@ -456,10 +483,10 @@ class LiveStreamRouterTest < ActionDispatch::IntegrationTest
     include ActionController::Live
 
     def index
-      response.headers['Content-Type'] = 'text/event-stream'
+      response.headers["Content-Type"] = "text/event-stream"
       sse = SSE.new(response.stream)
       sse.write("{\"name\":\"John\"}")
-      sse.write({ name: "Ryan" })
+      sse.write(name: "Ryan")
     ensure
       sse.close
     end
@@ -474,7 +501,7 @@ class LiveStreamRouterTest < ActionDispatch::IntegrationTest
   end
 
   routes.draw do
-    get '/test' => 'live_stream_router_test/test#index'
+    get "/test" => "live_stream_router_test/test#index"
   end
 
   def app
diff --git a/actionpack/test/controller/localized_templates_test.rb b/actionpack/test/controller/localized_templates_test.rb
index 3576015513..d84a76fb46 100644
--- a/actionpack/test/controller/localized_templates_test.rb
+++ b/actionpack/test/controller/localized_templates_test.rb
@@ -1,4 +1,6 @@
-require 'abstract_unit'
+# frozen_string_literal: true
+
+require "abstract_unit"
 
 class LocalizedController < ActionController::Base
   def hello_world
diff --git a/actionpack/test/controller/log_subscriber_test.rb b/actionpack/test/controller/log_subscriber_test.rb
index 57cf2dafdf..be455642de 100644
--- a/actionpack/test/controller/log_subscriber_test.rb
+++ b/actionpack/test/controller/log_subscriber_test.rb
@@ -1,10 +1,12 @@
+# frozen_string_literal: true
+
 require "abstract_unit"
 require "active_support/log_subscriber/test_helper"
 require "action_controller/log_subscriber"
 
 module Another
   class LogSubscribersController < ActionController::Base
-    wrap_parameters :person, :include => :name, :format => :json
+    wrap_parameters :person, include: :name, format: :json
 
     class SpecialException < Exception
     end
@@ -31,7 +33,7 @@ module Another
     end
 
     def data_sender
-      send_data "cool data", :filename => "file.txt"
+      send_data "cool data", filename: "file.txt"
     end
 
     def file_sender
@@ -39,27 +41,27 @@ module Another
     end
 
     def with_fragment_cache
-      render :inline => "<%= cache('foo'){ 'bar' } %>"
+      render inline: "<%= cache('foo'){ 'bar' } %>"
     end
 
     def with_fragment_cache_and_percent_in_key
-      render :inline => "<%= cache('foo%bar'){ 'Contains % sign in key' } %>"
+      render inline: "<%= cache('foo%bar'){ 'Contains % sign in key' } %>"
     end
 
     def with_fragment_cache_if_with_true_condition
-      render :inline => "<%= cache_if(true, 'foo') { 'bar' } %>"
+      render inline: "<%= cache_if(true, 'foo') { 'bar' } %>"
     end
 
     def with_fragment_cache_if_with_false_condition
-      render :inline => "<%= cache_if(false, 'foo') { 'bar' } %>"
+      render inline: "<%= cache_if(false, 'foo') { 'bar' } %>"
     end
 
     def with_fragment_cache_unless_with_false_condition
-      render :inline => "<%= cache_unless(false, 'foo') { 'bar' } %>"
+      render inline: "<%= cache_unless(false, 'foo') { 'bar' } %>"
     end
 
     def with_fragment_cache_unless_with_true_condition
-      render :inline => "<%= cache_unless(true, 'foo') { 'bar' } %>"
+      render inline: "<%= cache_unless(true, 'foo') { 'bar' } %>"
     end
 
     def with_exception
@@ -92,10 +94,11 @@ class ACLogSubscriberTest < ActionController::TestCase
 
   def setup
     super
+    ActionController::Base.enable_fragment_cache_logging = true
 
     @old_logger = ActionController::Base.logger
 
-    @cache_path = File.join Dir.tmpdir, Dir::Tmpname.make_tmpname('tmp', 'cache')
+    @cache_path = Dir.mktmpdir(%w[tmp cache])
     @controller.cache_store = :file_store, @cache_path
     ActionController::LogSubscriber.attach_to :action_controller
   end
@@ -105,6 +108,7 @@ class ACLogSubscriberTest < ActionController::TestCase
     ActiveSupport::LogSubscriber.log_subscribers.clear
     FileUtils.rm_rf(@cache_path)
     ActionController::Base.logger = @old_logger
+    ActionController::Base.enable_fragment_cache_logging = true
   end
 
   def set_logger(logger)
@@ -136,11 +140,11 @@ class ACLogSubscriberTest < ActionController::TestCase
   def test_process_action_without_parameters
     get :show
     wait
-    assert_nil logs.detect {|l| l =~ /Parameters/ }
+    assert_nil logs.detect { |l| l =~ /Parameters/ }
   end
 
   def test_process_action_with_parameters
-    get :show, params: { id: '10' }
+    get :show, params: { id: "10" }
     wait
 
     assert_equal 3, logs.size
@@ -148,8 +152,8 @@ class ACLogSubscriberTest < ActionController::TestCase
   end
 
   def test_multiple_process_with_parameters
-    get :show, params: { id: '10' }
-    get :show, params: { id: '20' }
+    get :show, params: { id: "10" }
+    get :show, params: { id: "20" }
 
     wait
 
@@ -159,8 +163,8 @@ class ACLogSubscriberTest < ActionController::TestCase
   end
 
   def test_process_action_with_wrapped_parameters
-    @request.env['CONTENT_TYPE'] = 'application/json'
-    post :show, params: { id: '10', name: 'jose' }
+    @request.env["CONTENT_TYPE"] = "application/json"
+    post :show, params: { id: "10", name: "jose" }
     wait
 
     assert_equal 3, logs.size
@@ -186,14 +190,14 @@ class ACLogSubscriberTest < ActionController::TestCase
   def test_process_action_headers
     get :show
     wait
-    assert_equal "Rails Testing", @controller.last_payload[:headers]['User-Agent']
+    assert_equal "Rails Testing", @controller.last_payload[:headers]["User-Agent"]
   end
 
   def test_process_action_with_filter_parameters
     @request.env["action_dispatch.parameter_filter"] = [:lifo, :amount]
 
     get :show, params: {
-      lifo: 'Pratik', amount: '420', step: '1'
+      lifo: "Pratik", amount: "420", step: "1"
     }
     wait
 
@@ -212,7 +216,7 @@ class ACLogSubscriberTest < ActionController::TestCase
   end
 
   def test_filter_redirect_url_by_string
-    @request.env['action_dispatch.redirect_filter'] = ['secret']
+    @request.env["action_dispatch.redirect_filter"] = ["secret"]
     get :filterable_redirector
     wait
 
@@ -221,7 +225,7 @@ class ACLogSubscriberTest < ActionController::TestCase
   end
 
   def test_filter_redirect_url_by_regexp
-    @request.env['action_dispatch.redirect_filter'] = [/secret\.foo.+/]
+    @request.env["action_dispatch.redirect_filter"] = [/secret\.foo.+/]
     get :filterable_redirector
     wait
 
@@ -258,6 +262,20 @@ class ACLogSubscriberTest < ActionController::TestCase
     @controller.config.perform_caching = true
   end
 
+  def test_with_fragment_cache_when_log_disabled
+    @controller.config.perform_caching = true
+    ActionController::Base.enable_fragment_cache_logging = false
+    get :with_fragment_cache
+    wait
+
+    assert_equal 2, logs.size
+    assert_equal "Processing by Another::LogSubscribersController#with_fragment_cache as HTML", logs[0]
+    assert_match(/Completed 200 OK in \d+ms/, logs[1])
+  ensure
+    @controller.config.perform_caching = true
+    ActionController::Base.enable_fragment_cache_logging = true
+  end
+
   def test_with_fragment_cache_if_with_true
     @controller.config.perform_caching = true
     get :with_fragment_cache_if_with_true_condition
diff --git a/actionpack/test/controller/metal/renderers_test.rb b/actionpack/test/controller/metal/renderers_test.rb
index 247e872674..5f0d125128 100644
--- a/actionpack/test/controller/metal/renderers_test.rb
+++ b/actionpack/test/controller/metal/renderers_test.rb
@@ -1,5 +1,7 @@
-require 'abstract_unit'
-require 'active_support/core_ext/hash/conversions'
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "active_support/core_ext/hash/conversions"
 
 class MetalRenderingController < ActionController::Metal
   include AbstractController::Rendering
@@ -10,11 +12,11 @@ end
 class MetalRenderingJsonController < MetalRenderingController
   class Model
     def to_json(options = {})
-      { a: 'b' }.to_json(options)
+      { a: "b" }.to_json(options)
     end
 
     def to_xml(options = {})
-      { a: 'b' }.to_xml(options)
+      { a: "b" }.to_xml(options)
     end
   end
 
@@ -35,14 +37,14 @@ class RenderersMetalTest < ActionController::TestCase
   def test_render_json
     get :one
     assert_response :success
-    assert_equal({ a: 'b' }.to_json, @response.body)
-    assert_equal 'application/json', @response.content_type
+    assert_equal({ a: "b" }.to_json, @response.body)
+    assert_equal "application/json", @response.content_type
   end
 
   def test_render_xml
     get :two
     assert_response :success
     assert_equal(" ", @response.body)
-    assert_equal 'text/plain', @response.content_type
+    assert_equal "text/plain", @response.content_type
   end
 end
diff --git a/actionpack/test/controller/metal_test.rb b/actionpack/test/controller/metal_test.rb
new file mode 100644
index 0000000000..c3ebcb22b8
--- /dev/null
+++ b/actionpack/test/controller/metal_test.rb
@@ -0,0 +1,32 @@
+# frozen_string_literal: true
+
+require "abstract_unit"
+
+class MetalControllerInstanceTests < ActiveSupport::TestCase
+  class SimpleController < ActionController::Metal
+    def hello
+      self.response_body = "hello"
+    end
+  end
+
+  def test_response_does_not_have_default_headers
+    original_default_headers = ActionDispatch::Response.default_headers
+
+    ActionDispatch::Response.default_headers = {
+      "X-Frame-Options" => "DENY",
+      "X-Content-Type-Options" => "nosniff",
+      "X-XSS-Protection" => "1;"
+    }
+
+    response_headers = SimpleController.action("hello").call(
+      "REQUEST_METHOD" => "GET",
+      "rack.input" => -> {}
+    )[1]
+
+    refute response_headers.key?("X-Frame-Options")
+    refute response_headers.key?("X-Content-Type-Options")
+    refute response_headers.key?("X-XSS-Protection")
+  ensure
+    ActionDispatch::Response.default_headers = original_default_headers
+  end
+end
diff --git a/actionpack/test/controller/mime/accept_format_test.rb b/actionpack/test/controller/mime/accept_format_test.rb
index e20c08da4e..eed671d593 100644
--- a/actionpack/test/controller/mime/accept_format_test.rb
+++ b/actionpack/test/controller/mime/accept_format_test.rb
@@ -1,4 +1,6 @@
-require 'abstract_unit'
+# frozen_string_literal: true
+
+require "abstract_unit"
 
 class StarStarMimeController < ActionController::Base
   layout nil
@@ -11,7 +13,7 @@ end
 class StarStarMimeControllerTest < ActionController::TestCase
   def test_javascript_with_format
     @request.accept = "text/javascript"
-    get :index, format: 'js'
+    get :index, format: "js"
     assert_match "function addition(a,b){ return a+b; }", @response.body
   end
 
@@ -29,7 +31,7 @@ class StarStarMimeControllerTest < ActionController::TestCase
 end
 
 class AbstractPostController < ActionController::Base
-  self.view_paths = File.dirname(__FILE__) + "/../../fixtures/post_test/"
+  self.view_paths = File.expand_path("../../fixtures/post_test", __dir__)
 end
 
 # For testing layouts which are set automatically
@@ -40,7 +42,7 @@ class PostController < AbstractPostController
     respond_to(:html, :iphone, :js)
   end
 
-protected
+private
 
   def with_iphone
     request.format = "iphone" if request.env["HTTP_ACCEPT"] == "text/iphone"
@@ -71,7 +73,7 @@ class MimeControllerLayoutsTest < ActionController::TestCase
 
     @request.accept = "text/iphone"
     get :index
-    assert_equal 'Hello iPhone', @response.body
+    assert_equal "Hello iPhone", @response.body
   end
 
   def test_format_with_inherited_layouts
diff --git a/actionpack/test/controller/mime/respond_to_test.rb b/actionpack/test/controller/mime/respond_to_test.rb
index 993f4001de..f9ffd5f54c 100644
--- a/actionpack/test/controller/mime/respond_to_test.rb
+++ b/actionpack/test/controller/mime/respond_to_test.rb
@@ -1,4 +1,6 @@
-require 'abstract_unit'
+# frozen_string_literal: true
+
+require "abstract_unit"
 require "active_support/log_subscriber/test_helper"
 
 class RespondToController < ActionController::Base
@@ -45,13 +47,12 @@ class RespondToController < ActionController::Base
 
   def json_xml_or_html
     respond_to do |type|
-      type.json { render body: 'JSON' }
-      type.xml { render :xml => 'XML' }
-      type.html { render body: 'HTML' }
+      type.json { render body: "JSON" }
+      type.xml { render xml: "XML" }
+      type.html { render body: "HTML" }
     end
   end
 
-
   def forced_xml
     request.format = :xml
 
@@ -77,7 +78,7 @@ class RespondToController < ActionController::Base
   def missing_templates
     respond_to do |type|
       # This test requires a block that is empty
-      type.json { }
+      type.json {}
       type.xml
     end
   end
@@ -109,7 +110,6 @@ class RespondToController < ActionController::Base
     end
   end
 
-
   def custom_constant_handling
     respond_to do |type|
       type.html   { render body: "HTML"   }
@@ -133,8 +133,8 @@ class RespondToController < ActionController::Base
 
   def handle_any_any
     respond_to do |type|
-      type.html { render body: 'HTML' }
-      type.any { render body: 'Whatever you ask for, I got it' }
+      type.html { render body: "HTML" }
+      type.any { render body: "Whatever you ask for, I got it" }
     end
   end
 
@@ -146,7 +146,7 @@ class RespondToController < ActionController::Base
 
   def json_with_callback
     respond_to do |type|
-      type.json { render :json => 'JS', :callback => 'alert' }
+      type.json { render json: "JS", callback: "alert" }
     end
   end
 
@@ -163,8 +163,8 @@ class RespondToController < ActionController::Base
     request.format = "iphone" if request.env["HTTP_ACCEPT"] == "text/iphone"
 
     respond_to do |type|
-      type.html   { @type = "Firefox"; render :action => "iphone_with_html_response_type" }
-      type.iphone { @type = "iPhone" ; render :action => "iphone_with_html_response_type" }
+      type.html   { @type = "Firefox"; render action: "iphone_with_html_response_type" }
+      type.iphone { @type = "iPhone" ; render action: "iphone_with_html_response_type" }
     end
   end
 
@@ -223,7 +223,7 @@ class RespondToController < ActionController::Base
   def variant_any
     respond_to do |format|
       format.html do |variant|
-        variant.any(:tablet, :phablet){ render body: "any" }
+        variant.any(:tablet, :phablet) { render body: "any" }
         variant.phone { render body: "phone" }
       end
     end
@@ -240,7 +240,7 @@ class RespondToController < ActionController::Base
 
   def variant_inline_any
     respond_to do |format|
-      format.html.any(:tablet, :phablet){ render body: "any" }
+      format.html.any(:tablet, :phablet) { render body: "any" }
       format.html.phone { render body: "phone" }
     end
   end
@@ -261,7 +261,7 @@ class RespondToController < ActionController::Base
 
   def variant_any_with_none
     respond_to do |format|
-      format.html.any(:none, :phone){ render body: "none or phone" }
+      format.html.any(:none, :phone) { render body: "none or phone" }
     end
   end
 
@@ -269,19 +269,19 @@ class RespondToController < ActionController::Base
     respond_to do |format|
       format.html { render body: "HTML" }
       format.any(:js, :xml) do |variant|
-        variant.phone{ render body: "phone" }
-        variant.any(:tablet, :phablet){ render body: "tablet" }
+        variant.phone { render body: "phone" }
+        variant.any(:tablet, :phablet) { render body: "tablet" }
       end
     end
   end
 
-  protected
+  private
     def set_layout
       case action_name
-        when "all_types_with_layout", "iphone_with_html_response_type"
-          "respond_to/layouts/standard"
-        when "iphone_with_html_response_type_without_layout"
-          "respond_to/layouts/missing"
+      when "all_types_with_layout", "iphone_with_html_response_type"
+        "respond_to/layouts/standard"
+      when "iphone_with_html_response_type_without_layout"
+        "respond_to/layouts/missing"
       end
     end
 end
@@ -305,10 +305,10 @@ class RespondToControllerTest < ActionController::TestCase
   def test_html
     @request.accept = "text/html"
     get :js_or_html
-    assert_equal 'HTML', @response.body
+    assert_equal "HTML", @response.body
 
     get :html_or_xml
-    assert_equal 'HTML', @response.body
+    assert_equal "HTML", @response.body
 
     assert_raises(ActionController::UnknownFormat) do
       get :just_xml
@@ -318,29 +318,29 @@ class RespondToControllerTest < ActionController::TestCase
   def test_all
     @request.accept = "*/*"
     get :js_or_html
-    assert_equal 'HTML', @response.body # js is not part of all
+    assert_equal "HTML", @response.body # js is not part of all
 
     get :html_or_xml
-    assert_equal 'HTML', @response.body
+    assert_equal "HTML", @response.body
 
     get :just_xml
-    assert_equal 'XML', @response.body
+    assert_equal "XML", @response.body
   end
 
   def test_xml
     @request.accept = "application/xml"
     get :html_xml_or_rss
-    assert_equal 'XML', @response.body
+    assert_equal "XML", @response.body
   end
 
   def test_js_or_html
     @request.accept = "text/javascript, text/html"
     get :js_or_html, xhr: true
-    assert_equal 'JS', @response.body
+    assert_equal "JS", @response.body
 
     @request.accept = "text/javascript, text/html"
     get :html_or_xml, xhr: true
-    assert_equal 'HTML', @response.body
+    assert_equal "HTML", @response.body
 
     @request.accept = "text/javascript, text/html"
 
@@ -352,25 +352,25 @@ class RespondToControllerTest < ActionController::TestCase
   def test_json_or_yaml_with_leading_star_star
     @request.accept = "*/*, application/json"
     get :json_xml_or_html
-    assert_equal 'HTML', @response.body
+    assert_equal "HTML", @response.body
 
     @request.accept = "*/* , application/json"
     get :json_xml_or_html
-    assert_equal 'HTML', @response.body
+    assert_equal "HTML", @response.body
   end
 
   def test_json_or_yaml
     get :json_or_yaml, xhr: true
-    assert_equal 'JSON', @response.body
+    assert_equal "JSON", @response.body
 
-    get :json_or_yaml, format: 'json'
-    assert_equal 'JSON', @response.body
+    get :json_or_yaml, format: "json"
+    assert_equal "JSON", @response.body
 
-    get :json_or_yaml, format: 'yaml'
-    assert_equal 'YAML', @response.body
+    get :json_or_yaml, format: "yaml"
+    assert_equal "YAML", @response.body
 
-    { 'YAML' => %w(text/yaml),
-      'JSON' => %w(application/json text/x-json)
+    { "YAML" => %w(text/yaml),
+      "JSON" => %w(application/json text/x-json)
     }.each do |body, content_types|
       content_types.each do |content_type|
         @request.accept = content_type
@@ -383,20 +383,20 @@ class RespondToControllerTest < ActionController::TestCase
   def test_js_or_anything
     @request.accept = "text/javascript, */*"
     get :js_or_html, xhr: true
-    assert_equal 'JS', @response.body
+    assert_equal "JS", @response.body
 
     get :html_or_xml, xhr: true
-    assert_equal 'HTML', @response.body
+    assert_equal "HTML", @response.body
 
     get :just_xml, xhr: true
-    assert_equal 'XML', @response.body
+    assert_equal "XML", @response.body
   end
 
   def test_using_defaults
     @request.accept = "*/*"
     get :using_defaults
     assert_equal "text/html", @response.content_type
-    assert_equal 'Hello world!', @response.body
+    assert_equal "Hello world!", @response.body
 
     @request.accept = "application/xml"
     get :using_defaults
@@ -422,7 +422,7 @@ class RespondToControllerTest < ActionController::TestCase
     @request.accept = "*/*"
     get :using_defaults_with_type_list
     assert_equal "text/html", @response.content_type
-    assert_equal 'Hello world!', @response.body
+    assert_equal "Hello world!", @response.body
 
     @request.accept = "application/xml"
     get :using_defaults_with_type_list
@@ -447,7 +447,7 @@ class RespondToControllerTest < ActionController::TestCase
   def test_synonyms
     @request.accept = "application/javascript"
     get :js_or_html
-    assert_equal 'JS', @response.body
+    assert_equal "JS", @response.body
 
     @request.accept = "application/x-xml"
     get :html_xml_or_rss
@@ -458,82 +458,82 @@ class RespondToControllerTest < ActionController::TestCase
     @request.accept = "application/crazy-xml"
     get :custom_type_handling
     assert_equal "application/crazy-xml", @response.content_type
-    assert_equal 'Crazy XML', @response.body
+    assert_equal "Crazy XML", @response.body
 
     @request.accept = "text/html"
     get :custom_type_handling
     assert_equal "text/html", @response.content_type
-    assert_equal 'HTML', @response.body
+    assert_equal "HTML", @response.body
   end
 
   def test_xhtml_alias
     @request.accept = "application/xhtml+xml,application/xml"
     get :html_or_xml
-    assert_equal 'HTML', @response.body
+    assert_equal "HTML", @response.body
   end
 
   def test_firefox_simulation
     @request.accept = "text/xml,application/xml,application/xhtml+xml,text/html;q=0.9,text/plain;q=0.8,image/png,*/*;q=0.5"
     get :html_or_xml
-    assert_equal 'HTML', @response.body
+    assert_equal "HTML", @response.body
   end
 
   def test_handle_any
     @request.accept = "*/*"
     get :handle_any
-    assert_equal 'HTML', @response.body
+    assert_equal "HTML", @response.body
 
     @request.accept = "text/javascript"
     get :handle_any
-    assert_equal 'Either JS or XML', @response.body
+    assert_equal "Either JS or XML", @response.body
 
     @request.accept = "text/xml"
     get :handle_any
-    assert_equal 'Either JS or XML', @response.body
+    assert_equal "Either JS or XML", @response.body
   end
 
   def test_handle_any_any
     @request.accept = "*/*"
     get :handle_any_any
-    assert_equal 'HTML', @response.body
+    assert_equal "HTML", @response.body
   end
 
   def test_handle_any_any_parameter_format
-    get :handle_any_any, format: 'html'
-    assert_equal 'HTML', @response.body
+    get :handle_any_any, format: "html"
+    assert_equal "HTML", @response.body
   end
 
   def test_handle_any_any_explicit_html
     @request.accept = "text/html"
     get :handle_any_any
-    assert_equal 'HTML', @response.body
+    assert_equal "HTML", @response.body
   end
 
   def test_handle_any_any_javascript
     @request.accept = "text/javascript"
     get :handle_any_any
-    assert_equal 'Whatever you ask for, I got it', @response.body
+    assert_equal "Whatever you ask for, I got it", @response.body
   end
 
   def test_handle_any_any_xml
     @request.accept = "text/xml"
     get :handle_any_any
-    assert_equal 'Whatever you ask for, I got it', @response.body
+    assert_equal "Whatever you ask for, I got it", @response.body
   end
 
-  def test_handle_any_any_unkown_format
-    get :handle_any_any, format: 'php'
-    assert_equal 'Whatever you ask for, I got it', @response.body
+  def test_handle_any_any_unknown_format
+    get :handle_any_any, format: "php"
+    assert_equal "Whatever you ask for, I got it", @response.body
   end
 
   def test_browser_check_with_any_any
     @request.accept = "application/json, application/xml"
     get :json_xml_or_html
-    assert_equal 'JSON', @response.body
+    assert_equal "JSON", @response.body
 
     @request.accept = "application/json, application/xml, */*"
     get :json_xml_or_html
-    assert_equal 'HTML', @response.body
+    assert_equal "HTML", @response.body
   end
 
   def test_html_type_with_layout
@@ -543,15 +543,15 @@ class RespondToControllerTest < ActionController::TestCase
   end
 
   def test_json_with_callback_sets_javascript_content_type
-    @request.accept = 'application/json'
+    @request.accept = "application/json"
     get :json_with_callback
-    assert_equal '/**/alert(JS)', @response.body
-    assert_equal 'text/javascript', @response.content_type
+    assert_equal "/**/alert(JS)", @response.body
+    assert_equal "text/javascript", @response.content_type
   end
 
   def test_xhr
     get :js_or_html, xhr: true
-    assert_equal 'JS', @response.body
+    assert_equal "JS", @response.body
   end
 
   def test_custom_constant
@@ -676,7 +676,7 @@ class RespondToControllerTest < ActionController::TestCase
     get :variant_without_implicit_template_rendering, xhr: true, params: { v: :does_not_matter }
     assert_response :no_content
 
-    assert_equal 1, logger.logged(:info).select{ |s| s == NO_CONTENT_WARNING }.size, "Implicit head :no_content not logged"
+    assert_equal 1, logger.logged(:info).select { |s| s == NO_CONTENT_WARNING }.size, "Implicit head :no_content not logged"
   ensure
     ActionController::Base.logger = old_logger
   end
@@ -685,10 +685,10 @@ class RespondToControllerTest < ActionController::TestCase
     logger = ActiveSupport::LogSubscriber::TestHelper::MockLogger.new
     old_logger, ActionController::Base.logger = ActionController::Base.logger, logger
 
-    get :variant_without_implicit_template_rendering, format: 'json', params: { v: :does_not_matter }
+    get :variant_without_implicit_template_rendering, format: "json", params: { v: :does_not_matter }
     assert_response :no_content
 
-    assert_equal 1, logger.logged(:info).select{ |s| s == NO_CONTENT_WARNING }.size, "Implicit head :no_content not logged"
+    assert_equal 1, logger.logged(:info).select { |s| s == NO_CONTENT_WARNING }.size, "Implicit head :no_content not logged"
   ensure
     ActionController::Base.logger = old_logger
   end
diff --git a/actionpack/test/controller/new_base/bare_metal_test.rb b/actionpack/test/controller/new_base/bare_metal_test.rb
index ee3c498b1c..b049022a06 100644
--- a/actionpack/test/controller/new_base/bare_metal_test.rb
+++ b/actionpack/test/controller/new_base/bare_metal_test.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require "abstract_unit"
 
 module BareMetalTest
@@ -11,7 +13,7 @@ module BareMetalTest
     test "response body is a Rack-compatible response" do
       status, headers, body = BareController.action(:index).call(Rack::MockRequest.env_for("/"))
       assert_equal 200, status
-      string = ""
+      string = "".dup
 
       body.each do |part|
         assert part.is_a?(String), "Each part of the body must be a String"
@@ -52,7 +54,7 @@ module BareMetalTest
       controller.set_request!(ActionDispatch::Request.empty)
       controller.set_response!(BareController.make_response!(controller.request))
       controller.index
-      assert_equal nil, controller.response_body
+      assert_nil controller.response_body
     end
   end
 
@@ -102,38 +104,38 @@ module BareMetalTest
 
     test "head :continue (100) does not return a content-type header" do
       headers = HeadController.action(:continue).call(Rack::MockRequest.env_for("/")).second
-      assert_nil headers['Content-Type']
-      assert_nil headers['Content-Length']
+      assert_nil headers["Content-Type"]
+      assert_nil headers["Content-Length"]
     end
 
     test "head :switching_protocols (101) does not return a content-type header" do
       headers = HeadController.action(:switching_protocols).call(Rack::MockRequest.env_for("/")).second
-      assert_nil headers['Content-Type']
-      assert_nil headers['Content-Length']
+      assert_nil headers["Content-Type"]
+      assert_nil headers["Content-Length"]
     end
 
     test "head :processing (102) does not return a content-type header" do
       headers = HeadController.action(:processing).call(Rack::MockRequest.env_for("/")).second
-      assert_nil headers['Content-Type']
-      assert_nil headers['Content-Length']
+      assert_nil headers["Content-Type"]
+      assert_nil headers["Content-Length"]
     end
 
     test "head :no_content (204) does not return a content-type header" do
       headers = HeadController.action(:no_content).call(Rack::MockRequest.env_for("/")).second
-      assert_nil headers['Content-Type']
-      assert_nil headers['Content-Length']
+      assert_nil headers["Content-Type"]
+      assert_nil headers["Content-Length"]
     end
 
     test "head :reset_content (205) does not return a content-type header" do
       headers = HeadController.action(:reset_content).call(Rack::MockRequest.env_for("/")).second
-      assert_nil headers['Content-Type']
-      assert_nil headers['Content-Length']
+      assert_nil headers["Content-Type"]
+      assert_nil headers["Content-Length"]
     end
 
     test "head :not_modified (304) does not return a content-type header" do
       headers = HeadController.action(:not_modified).call(Rack::MockRequest.env_for("/")).second
-      assert_nil headers['Content-Type']
-      assert_nil headers['Content-Length']
+      assert_nil headers["Content-Type"]
+      assert_nil headers["Content-Length"]
     end
 
     test "head :no_content (204) does not return any content" do
diff --git a/actionpack/test/controller/new_base/base_test.rb b/actionpack/test/controller/new_base/base_test.rb
index 0755dafe93..280134f8d2 100644
--- a/actionpack/test/controller/new_base/base_test.rb
+++ b/actionpack/test/controller/new_base/base_test.rb
@@ -1,4 +1,6 @@
-require 'abstract_unit'
+# frozen_string_literal: true
+
+require "abstract_unit"
 
 # Tests the controller dispatching happy path
 module Dispatching
@@ -25,7 +27,7 @@ module Dispatching
       render body: "actions: #{action_methods.to_a.sort.join(', ')}"
     end
 
-    protected
+    private
       def authenticate
       end
   end
@@ -45,7 +47,6 @@ module Dispatching
   end
 
   class BaseTest < Rack::TestCase
-    # :api: plugin
     test "simple dispatching" do
       get "/dispatching/simple/index"
 
@@ -54,14 +55,12 @@ module Dispatching
       assert_content_type "text/plain; charset=utf-8"
     end
 
-    # :api: plugin
     test "directly modifying response body" do
       get "/dispatching/simple/modify_response_body"
 
       assert_body "success"
     end
 
-    # :api: plugin
     test "directly modifying response body twice" do
       get "/dispatching/simple/modify_response_body_twice"
 
@@ -69,48 +68,48 @@ module Dispatching
     end
 
     test "controller path" do
-      assert_equal 'dispatching/empty', EmptyController.controller_path
+      assert_equal "dispatching/empty", EmptyController.controller_path
       assert_equal EmptyController.controller_path, EmptyController.new.controller_path
     end
 
     test "non-default controller path" do
-      assert_equal 'i_am_not_default', NonDefaultPathController.controller_path
+      assert_equal "i_am_not_default", NonDefaultPathController.controller_path
       assert_equal NonDefaultPathController.controller_path, NonDefaultPathController.new.controller_path
     end
 
     test "sub controller path" do
-      assert_equal 'dispatching/sub_empty', SubEmptyController.controller_path
+      assert_equal "dispatching/sub_empty", SubEmptyController.controller_path
       assert_equal SubEmptyController.controller_path, SubEmptyController.new.controller_path
     end
 
     test "namespaced controller path" do
-      assert_equal 'dispatching/submodule/contained_empty', Submodule::ContainedEmptyController.controller_path
+      assert_equal "dispatching/submodule/contained_empty", Submodule::ContainedEmptyController.controller_path
       assert_equal Submodule::ContainedEmptyController.controller_path, Submodule::ContainedEmptyController.new.controller_path
     end
 
     test "namespaced non-default controller path" do
-      assert_equal 'i_am_extremely_not_default', Submodule::ContainedNonDefaultPathController.controller_path
+      assert_equal "i_am_extremely_not_default", Submodule::ContainedNonDefaultPathController.controller_path
       assert_equal Submodule::ContainedNonDefaultPathController.controller_path, Submodule::ContainedNonDefaultPathController.new.controller_path
     end
 
     test "namespaced sub controller path" do
-      assert_equal 'dispatching/submodule/contained_sub_empty', Submodule::ContainedSubEmptyController.controller_path
+      assert_equal "dispatching/submodule/contained_sub_empty", Submodule::ContainedSubEmptyController.controller_path
       assert_equal Submodule::ContainedSubEmptyController.controller_path, Submodule::ContainedSubEmptyController.new.controller_path
     end
 
     test "controller name" do
-      assert_equal 'empty', EmptyController.controller_name
-      assert_equal 'contained_empty', Submodule::ContainedEmptyController.controller_name
+      assert_equal "empty", EmptyController.controller_name
+      assert_equal "contained_empty", Submodule::ContainedEmptyController.controller_name
     end
 
     test "non-default path controller name" do
-      assert_equal 'non_default_path', NonDefaultPathController.controller_name
-      assert_equal 'contained_non_default_path', Submodule::ContainedNonDefaultPathController.controller_name
+      assert_equal "non_default_path", NonDefaultPathController.controller_name
+      assert_equal "contained_non_default_path", Submodule::ContainedNonDefaultPathController.controller_name
     end
 
     test "sub controller name" do
-      assert_equal 'sub_empty', SubEmptyController.controller_name
-      assert_equal 'contained_sub_empty', Submodule::ContainedSubEmptyController.controller_name
+      assert_equal "sub_empty", SubEmptyController.controller_name
+      assert_equal "contained_sub_empty", Submodule::ContainedSubEmptyController.controller_name
     end
 
     test "action methods" do
diff --git a/actionpack/test/controller/new_base/content_negotiation_test.rb b/actionpack/test/controller/new_base/content_negotiation_test.rb
index c0e92b3b05..7205e90176 100644
--- a/actionpack/test/controller/new_base/content_negotiation_test.rb
+++ b/actionpack/test/controller/new_base/content_negotiation_test.rb
@@ -1,7 +1,8 @@
-require 'abstract_unit'
+# frozen_string_literal: true
 
-module ContentNegotiation
+require "abstract_unit"
 
+module ContentNegotiation
   # This has no layout and it works
   class BasicController < ActionController::Base
     self.view_paths = [ActionView::FixtureResolver.new(
@@ -9,7 +10,7 @@ module ContentNegotiation
     )]
 
     def all
-      render plain: self.formats.inspect
+      render plain: formats.inspect
     end
   end
 
diff --git a/actionpack/test/controller/new_base/content_type_test.rb b/actionpack/test/controller/new_base/content_type_test.rb
index 0b3a26807d..d3ee4a8a6f 100644
--- a/actionpack/test/controller/new_base/content_type_test.rb
+++ b/actionpack/test/controller/new_base/content_type_test.rb
@@ -1,4 +1,6 @@
-require 'abstract_unit'
+# frozen_string_literal: true
+
+require "abstract_unit"
 
 module ContentType
   class BaseController < ActionController::Base
@@ -44,7 +46,7 @@ module ContentType
       with_routing do |set|
         set.draw do
           ActiveSupport::Deprecation.silence do
-            get ':controller', :action => 'index'
+            get ":controller", action: "index"
           end
         end
 
diff --git a/actionpack/test/controller/new_base/middleware_test.rb b/actionpack/test/controller/new_base/middleware_test.rb
index 85a1f351f0..df69650a7b 100644
--- a/actionpack/test/controller/new_base/middleware_test.rb
+++ b/actionpack/test/controller/new_base/middleware_test.rb
@@ -1,4 +1,6 @@
-require 'abstract_unit'
+# frozen_string_literal: true
+
+require "abstract_unit"
 
 module MiddlewareTest
   class MyMiddleware
@@ -21,7 +23,7 @@ module MiddlewareTest
 
     def call(env)
       result = @app.call(env)
-      result[1]["Middleware-Order"] << "!"
+      result[1]["Middleware-Order"] += "!"
       result
     end
   end
@@ -56,8 +58,8 @@ module MiddlewareTest
   end
 
   class ActionsController < ActionController::Metal
-    use MyMiddleware, :only => :show
-    middleware.insert_before MyMiddleware, ExclaimerMiddleware, :except => :index
+    use MyMiddleware, only: :show
+    middleware.insert_before MyMiddleware, ExclaimerMiddleware, except: :index
 
     def index
       self.response_body = "index"
diff --git a/actionpack/test/controller/new_base/render_action_test.rb b/actionpack/test/controller/new_base/render_action_test.rb
index 3bf1dd0ede..33b55dc5a8 100644
--- a/actionpack/test/controller/new_base/render_action_test.rb
+++ b/actionpack/test/controller/new_base/render_action_test.rb
@@ -1,4 +1,6 @@
-require 'abstract_unit'
+# frozen_string_literal: true
+
+require "abstract_unit"
 
 module RenderAction
   # This has no layout and it works
@@ -8,7 +10,7 @@ module RenderAction
     )]
 
     def hello_world
-      render :action => "hello_world"
+      render action: "hello_world"
     end
 
     def hello_world_as_string
@@ -16,7 +18,7 @@ module RenderAction
     end
 
     def hello_world_as_string_with_options
-      render "hello_world", :status => 404
+      render "hello_world", status: 404
     end
 
     def hello_world_as_symbol
@@ -24,25 +26,24 @@ module RenderAction
     end
 
     def hello_world_with_symbol
-      render :action => :hello_world
+      render action: :hello_world
     end
 
     def hello_world_with_layout
-      render :action => "hello_world", :layout => true
+      render action: "hello_world", layout: true
     end
 
     def hello_world_with_layout_false
-      render :action => "hello_world", :layout => false
+      render action: "hello_world", layout: false
     end
 
     def hello_world_with_layout_nil
-      render :action => "hello_world", :layout => nil
+      render action: "hello_world", layout: nil
     end
 
     def hello_world_with_custom_layout
-      render :action => "hello_world", :layout => "greetings"
+      render action: "hello_world", layout: "greetings"
     end
-
   end
 
   class RenderActionTest < Rack::TestCase
@@ -127,27 +128,27 @@ module RenderActionWithApplicationLayout
     )]
 
     def hello_world
-      render :action => "hello_world"
+      render action: "hello_world"
     end
 
     def hello_world_with_layout
-      render :action => "hello_world", :layout => true
+      render action: "hello_world", layout: true
     end
 
     def hello_world_with_layout_false
-      render :action => "hello_world", :layout => false
+      render action: "hello_world", layout: false
     end
 
     def hello_world_with_layout_nil
-      render :action => "hello_world", :layout => nil
+      render action: "hello_world", layout: nil
     end
 
     def hello_world_with_custom_layout
-      render :action => "hello_world", :layout => "greetings"
+      render action: "hello_world", layout: "greetings"
     end
 
     def with_builder_and_layout
-      render :action => "hello", :layout => "builder"
+      render action: "hello", layout: "builder"
     end
   end
 
@@ -196,7 +197,6 @@ module RenderActionWithApplicationLayout
       assert_response "<html>\n<p>Hello</p>\n</html>\n"
     end
   end
-
 end
 
 module RenderActionWithControllerLayout
@@ -207,23 +207,23 @@ module RenderActionWithControllerLayout
     )]
 
     def hello_world
-      render :action => "hello_world"
+      render action: "hello_world"
     end
 
     def hello_world_with_layout
-      render :action => "hello_world", :layout => true
+      render action: "hello_world", layout: true
     end
 
     def hello_world_with_layout_false
-      render :action => "hello_world", :layout => false
+      render action: "hello_world", layout: false
     end
 
     def hello_world_with_layout_nil
-      render :action => "hello_world", :layout => nil
+      render action: "hello_world", layout: nil
     end
 
     def hello_world_with_custom_layout
-      render :action => "hello_world", :layout => "greetings"
+      render action: "hello_world", layout: "greetings"
     end
   end
 
@@ -260,26 +260,25 @@ end
 
 module RenderActionWithBothLayouts
   class BasicController < ActionController::Base
-    self.view_paths = [ActionView::FixtureResolver.new({
-      "render_action_with_both_layouts/basic/hello_world.html.erb" => "Hello World!",
+    self.view_paths = [ActionView::FixtureResolver.new(
+      "render_action_with_both_layouts/basic/hello_world.html.erb"  => "Hello World!",
       "layouts/application.html.erb"                                => "Oh Hi <%= yield %> Bye",
-      "layouts/render_action_with_both_layouts/basic.html.erb"      => "With Controller Layout! <%= yield %> Bye"
-    })]
+      "layouts/render_action_with_both_layouts/basic.html.erb"      => "With Controller Layout! <%= yield %> Bye")]
 
     def hello_world
-      render :action => "hello_world"
+      render action: "hello_world"
     end
 
     def hello_world_with_layout
-      render :action => "hello_world", :layout => true
+      render action: "hello_world", layout: true
     end
 
     def hello_world_with_layout_false
-      render :action => "hello_world", :layout => false
+      render action: "hello_world", layout: false
     end
 
     def hello_world_with_layout_nil
-      render :action => "hello_world", :layout => nil
+      render action: "hello_world", layout: nil
     end
   end
 
diff --git a/actionpack/test/controller/new_base/render_body_test.rb b/actionpack/test/controller/new_base/render_body_test.rb
index c65c245773..d0b61f0665 100644
--- a/actionpack/test/controller/new_base/render_body_test.rb
+++ b/actionpack/test/controller/new_base/render_body_test.rb
@@ -1,4 +1,6 @@
-require 'abstract_unit'
+# frozen_string_literal: true
+
+require "abstract_unit"
 
 module RenderBody
   class MinimalController < ActionController::Metal
@@ -66,7 +68,7 @@ module RenderBody
     end
 
     def with_custom_content_type
-      response.headers['Content-Type'] = 'application/json'
+      response.headers["Content-Type"] = "application/json"
       render body: '["troll","face"]'
     end
 
@@ -85,7 +87,7 @@ module RenderBody
 
     test "rendering body from an action with default options renders the body with the layout" do
       with_routing do |set|
-        set.draw { ActiveSupport::Deprecation.silence { get ':controller', action: 'index' } }
+        set.draw { ActiveSupport::Deprecation.silence { get ":controller", action: "index" } }
 
         get "/render_body/simple"
         assert_body "hello david"
@@ -95,7 +97,7 @@ module RenderBody
 
     test "rendering body from an action with default options renders the body without the layout" do
       with_routing do |set|
-        set.draw { ActiveSupport::Deprecation.silence { get ':controller', action: 'index' } }
+        set.draw { ActiveSupport::Deprecation.silence { get ":controller", action: "index" } }
 
         get "/render_body/with_layout"
 
@@ -150,7 +152,7 @@ module RenderBody
       get "/render_body/with_layout/with_custom_content_type"
 
       assert_equal %w{ troll face }, JSON.parse(response.body)
-      assert_equal 'application/json', response.headers['Content-Type']
+      assert_equal "application/json", response.headers["Content-Type"]
     end
 
     test "rendering body with layout: false" do
diff --git a/actionpack/test/controller/new_base/render_context_test.rb b/actionpack/test/controller/new_base/render_context_test.rb
index 177a1c088d..07fbadae9f 100644
--- a/actionpack/test/controller/new_base/render_context_test.rb
+++ b/actionpack/test/controller/new_base/render_context_test.rb
@@ -1,4 +1,6 @@
-require 'abstract_unit'
+# frozen_string_literal: true
+
+require "abstract_unit"
 
 # This is testing the decoupling of view renderer and view context
 # by allowing the controller to be used as view context. This is
@@ -18,24 +20,22 @@ module RenderContext
 
     def hello_world
       @value = "Hello"
-      render :action => "hello_world", :layout => false
+      render action: "hello_world", layout: false
     end
 
     def with_layout
       @value = "Hello"
-      render :action => "hello_world", :layout => "basic"
+      render action: "hello_world", layout: "basic"
     end
 
-    protected
+    protected def __controller_method__
+      "controller context!"
+    end
 
     # 3) Set view_context to self
-    def view_context
+    private def view_context
       self
     end
-
-    def __controller_method__
-      "controller context!"
-    end
   end
 
   class RenderContextTest < Rack::TestCase
diff --git a/actionpack/test/controller/new_base/render_file_test.rb b/actionpack/test/controller/new_base/render_file_test.rb
index 0c21bb0719..de8af029e0 100644
--- a/actionpack/test/controller/new_base/render_file_test.rb
+++ b/actionpack/test/controller/new_base/render_file_test.rb
@@ -1,36 +1,38 @@
-require 'abstract_unit'
+# frozen_string_literal: true
+
+require "abstract_unit"
 
 module RenderFile
   class BasicController < ActionController::Base
-    self.view_paths = File.dirname(__FILE__)
+    self.view_paths = __dir__
 
     def index
-      render :file => File.join(File.dirname(__FILE__), *%w[.. .. fixtures test hello_world])
+      render file: File.expand_path("../../fixtures/test/hello_world", __dir__)
     end
 
     def with_instance_variables
-      @secret = 'in the sauce'
-      render :file => File.join(File.dirname(__FILE__), '../../fixtures/test/render_file_with_ivar')
+      @secret = "in the sauce"
+      render file: File.expand_path("../../fixtures/test/render_file_with_ivar", __dir__)
     end
 
     def relative_path
-      @secret = 'in the sauce'
-      render :file => '../../fixtures/test/render_file_with_ivar'
+      @secret = "in the sauce"
+      render file: "../../fixtures/test/render_file_with_ivar"
     end
 
     def relative_path_with_dot
-      @secret = 'in the sauce'
-      render :file => '../../fixtures/test/dot.directory/render_file_with_ivar'
+      @secret = "in the sauce"
+      render file: "../../fixtures/test/dot.directory/render_file_with_ivar"
     end
 
     def pathname
-      @secret = 'in the sauce'
-      render :file => Pathname.new(File.dirname(__FILE__)).join(*%w[.. .. fixtures test dot.directory render_file_with_ivar])
+      @secret = "in the sauce"
+      render file: Pathname.new(__dir__).join(*%w[.. .. fixtures test dot.directory render_file_with_ivar])
     end
 
     def with_locals
-      path = File.join(File.dirname(__FILE__), '../../fixtures/test/render_file_with_locals')
-      render :file => path, :locals => {:secret => 'in the sauce'}
+      path = File.expand_path("../../fixtures/test/render_file_with_locals", __dir__)
+      render file: path, locals: { secret: "in the sauce" }
     end
   end
 
diff --git a/actionpack/test/controller/new_base/render_html_test.rb b/actionpack/test/controller/new_base/render_html_test.rb
index bfed136496..4bea2ba2e9 100644
--- a/actionpack/test/controller/new_base/render_html_test.rb
+++ b/actionpack/test/controller/new_base/render_html_test.rb
@@ -1,4 +1,6 @@
-require 'abstract_unit'
+# frozen_string_literal: true
+
+require "abstract_unit"
 
 module RenderHtml
   class MinimalController < ActionController::Metal
@@ -88,7 +90,7 @@ module RenderHtml
 
     test "rendering text from an action with default options renders the text with the layout" do
       with_routing do |set|
-        set.draw { ActiveSupport::Deprecation.silence { get ':controller', action: 'index' } }
+        set.draw { ActiveSupport::Deprecation.silence { get ":controller", action: "index" } }
 
         get "/render_html/simple"
         assert_body "hello david"
@@ -98,7 +100,7 @@ module RenderHtml
 
     test "rendering text from an action with default options renders the text without the layout" do
       with_routing do |set|
-        set.draw { ActiveSupport::Deprecation.silence { get ':controller', action: 'index' } }
+        set.draw { ActiveSupport::Deprecation.silence { get ":controller", action: "index" } }
 
         get "/render_html/with_layout"
 
diff --git a/actionpack/test/controller/new_base/render_implicit_action_test.rb b/actionpack/test/controller/new_base/render_implicit_action_test.rb
index 5b4885f7e0..8c26d34b00 100644
--- a/actionpack/test/controller/new_base/render_implicit_action_test.rb
+++ b/actionpack/test/controller/new_base/render_implicit_action_test.rb
@@ -1,4 +1,6 @@
-require 'abstract_unit'
+# frozen_string_literal: true
+
+require "abstract_unit"
 
 module RenderImplicitAction
   class SimpleController < ::ApplicationController
@@ -6,7 +8,7 @@ module RenderImplicitAction
       "render_implicit_action/simple/hello_world.html.erb"     => "Hello world!",
       "render_implicit_action/simple/hyphen-ated.html.erb"     => "Hello hyphen-ated!",
       "render_implicit_action/simple/not_implemented.html.erb" => "Not Implemented"
-    ), ActionView::FileSystemResolver.new(File.expand_path('../../../controller', __FILE__))]
+    ), ActionView::FileSystemResolver.new(File.expand_path("../../controller", __dir__))]
 
     def hello_world() end
   end
diff --git a/actionpack/test/controller/new_base/render_layout_test.rb b/actionpack/test/controller/new_base/render_layout_test.rb
index 7ab3777026..806c6206dc 100644
--- a/actionpack/test/controller/new_base/render_layout_test.rb
+++ b/actionpack/test/controller/new_base/render_layout_test.rb
@@ -1,4 +1,6 @@
-require 'abstract_unit'
+# frozen_string_literal: true
+
+require "abstract_unit"
 
 module ControllerLayouts
   class ImplicitController < ::ApplicationController
@@ -10,15 +12,15 @@ module ControllerLayouts
     )]
 
     def index
-      render :template => "basic"
+      render template: "basic"
     end
 
     def override
-      render :template => "basic", :layout => "override"
+      render template: "basic", layout: "override"
     end
 
     def layout_false
-      render :layout => false
+      render layout: false
     end
 
     def builder_override
@@ -32,7 +34,7 @@ module ControllerLayouts
     )]
 
     def index
-      render :template => "basic"
+      render template: "basic"
     end
   end
 
@@ -55,7 +57,6 @@ module ControllerLayouts
       get "/controller_layouts/implicit/override"
       assert_body "Override! Hello world!"
     end
-
   end
 
   class LayoutOptionsTest < Rack::TestCase
@@ -76,7 +77,7 @@ module ControllerLayouts
     )]
 
     def explicit
-      render :layout => "application"
+      render layout: "application"
     end
   end
 
diff --git a/actionpack/test/controller/new_base/render_partial_test.rb b/actionpack/test/controller/new_base/render_partial_test.rb
index 9e5022c9f4..a0c7cbc686 100644
--- a/actionpack/test/controller/new_base/render_partial_test.rb
+++ b/actionpack/test/controller/new_base/render_partial_test.rb
@@ -1,9 +1,9 @@
-require 'abstract_unit'
+# frozen_string_literal: true
 
-module RenderPartial
+require "abstract_unit"
 
+module RenderPartial
   class BasicController < ActionController::Base
-
     self.view_paths = [ActionView::FixtureResolver.new(
       "render_partial/basic/_basic.html.erb"      => "BasicPartial!",
       "render_partial/basic/basic.html.erb"       => "<%= @test_unchanged = 'goodbye' %><%= render :partial => 'basic' %><%= @test_unchanged %>",
@@ -16,16 +16,16 @@ module RenderPartial
     )]
 
     def html_with_json_inside_json
-      render :action => "with_json"
+      render action: "with_json"
     end
 
     def changing
-      @test_unchanged = 'hello'
-      render :action => "basic"
+      @test_unchanged = "hello"
+      render action: "basic"
     end
 
     def overridden
-      @test_unchanged = 'hello'
+      @test_unchanged = "hello"
     end
   end
 
@@ -59,5 +59,4 @@ module RenderPartial
       assert_response("goodbyeOverriddenPartial!goodbye")
     end
   end
-
 end
diff --git a/actionpack/test/controller/new_base/render_plain_test.rb b/actionpack/test/controller/new_base/render_plain_test.rb
index 94afe7bcfe..640979e4f5 100644
--- a/actionpack/test/controller/new_base/render_plain_test.rb
+++ b/actionpack/test/controller/new_base/render_plain_test.rb
@@ -1,4 +1,6 @@
-require 'abstract_unit'
+# frozen_string_literal: true
+
+require "abstract_unit"
 
 module RenderPlain
   class MinimalController < ActionController::Metal
@@ -80,7 +82,7 @@ module RenderPlain
 
     test "rendering text from an action with default options renders the text with the layout" do
       with_routing do |set|
-        set.draw { ActiveSupport::Deprecation.silence { get ':controller', action: 'index' } }
+        set.draw { ActiveSupport::Deprecation.silence { get ":controller", action: "index" } }
 
         get "/render_plain/simple"
         assert_body "hello david"
@@ -90,7 +92,7 @@ module RenderPlain
 
     test "rendering text from an action with default options renders the text without the layout" do
       with_routing do |set|
-        set.draw { ActiveSupport::Deprecation.silence { get ':controller', action: 'index' } }
+        set.draw { ActiveSupport::Deprecation.silence { get ":controller", action: "index" } }
 
         get "/render_plain/with_layout"
 
diff --git a/actionpack/test/controller/new_base/render_streaming_test.rb b/actionpack/test/controller/new_base/render_streaming_test.rb
index 9ea056194a..23dc6bca40 100644
--- a/actionpack/test/controller/new_base/render_streaming_test.rb
+++ b/actionpack/test/controller/new_base/render_streaming_test.rb
@@ -1,4 +1,6 @@
-require 'abstract_unit'
+# frozen_string_literal: true
+
+require "abstract_unit"
 
 module RenderStreaming
   class BasicController < ActionController::Base
@@ -12,32 +14,32 @@ module RenderStreaming
     layout "application"
 
     def hello_world
-      render :stream => true
+      render stream: true
     end
 
     def layout_exception
-      render :action => "hello_world", :stream => true, :layout => "boom"
+      render action: "hello_world", stream: true, layout: "boom"
     end
 
     def template_exception
-      render :action => "boom", :stream => true
+      render action: "boom", stream: true
     end
 
     def skip
-      render :action => "hello_world", :stream => false
+      render action: "hello_world", stream: false
     end
 
     def explicit
-      render :action => "hello_world", :stream => true
+      render action: "hello_world", stream: true
     end
 
     def no_layout
-      render :action => "hello_world", :stream => true, :layout => false
+      render action: "hello_world", stream: true, layout: false
     end
 
     def explicit_cache
       headers["Cache-Control"] = "private"
-      render :action => "hello_world", :stream => true
+      render action: "hello_world", stream: true
     end
   end
 
@@ -101,12 +103,12 @@ module RenderStreaming
       assert_body "Hello world, I'm here!"
       assert_status 200
       assert_equal "22", headers["Content-Length"]
-      assert_equal nil, headers["Transfer-Encoding"]
+      assert_nil headers["Transfer-Encoding"]
     end
 
-    def assert_streaming!(cache="no-cache")
+    def assert_streaming!(cache = "no-cache")
       assert_status 200
-      assert_equal nil, headers["Content-Length"]
+      assert_nil headers["Content-Length"]
       assert_equal "chunked", headers["Transfer-Encoding"]
       assert_equal cache, headers["Cache-Control"]
     end
diff --git a/actionpack/test/controller/new_base/render_template_test.rb b/actionpack/test/controller/new_base/render_template_test.rb
index 0d4c7cdb0a..14dc958475 100644
--- a/actionpack/test/controller/new_base/render_template_test.rb
+++ b/actionpack/test/controller/new_base/render_template_test.rb
@@ -1,8 +1,9 @@
-require 'abstract_unit'
+# frozen_string_literal: true
+
+require "abstract_unit"
 
 module RenderTemplate
   class WithoutLayoutController < ActionController::Base
-
     self.view_paths = [ActionView::FixtureResolver.new(
       "test/basic.html.erb"        => "Hello from basic.html.erb",
       "shared.html.erb"            => "Elastica",
@@ -18,11 +19,11 @@ module RenderTemplate
     )]
 
     def index
-      render :template => "test/basic"
+      render template: "test/basic"
     end
 
     def html_with_json_inside_json
-      render :template => "test/with_json"
+      render template: "test/with_json"
     end
 
     def index_without_key
@@ -30,46 +31,46 @@ module RenderTemplate
     end
 
     def in_top_directory
-      render :template => 'shared'
+      render template: "shared"
     end
 
     def in_top_directory_with_slash
-      render :template => '/shared'
+      render template: "/shared"
     end
 
     def in_top_directory_with_slash_without_key
-      render '/shared'
+      render "/shared"
     end
 
     def with_locals
-      render :template => "locals", :locals => { :secret => 'area51' }
+      render template: "locals", locals: { secret: "area51" }
     end
 
     def with_locals_without_key
-      render "locals", :locals => { :secret => 'area51' }
+      render "locals", locals: { secret: "area51" }
     end
 
     def builder_template
-      render :template => "xml_template"
+      render template: "xml_template"
     end
 
     def with_raw
-      render :template => "with_raw"
+      render template: "with_raw"
     end
 
     def with_implicit_raw
-      render :template => "with_implicit_raw"
+      render template: "with_implicit_raw"
     end
 
     def with_error
-      render :template => "test/with_error"
+      render template: "test/with_error"
     end
 
     private
 
-    def show_detailed_exceptions?
-      request.local?
-    end
+      def show_detailed_exceptions?
+        request.local?
+      end
   end
 
   class TestWithoutLayout < Rack::TestCase
@@ -126,7 +127,7 @@ module RenderTemplate
       assert_body "Hello <strong>this is also raw</strong> in an html template"
       assert_status 200
 
-      get :with_implicit_raw, params: { format: 'text' }
+      get :with_implicit_raw, params: { format: "text" }
 
       assert_body "Hello <strong>this is also raw</strong> in a text template"
       assert_status 200
@@ -154,30 +155,30 @@ module RenderTemplate
     )]
 
     def index
-      render :template => "test/basic"
+      render template: "test/basic"
     end
 
     def with_layout
-      render :template => "test/basic", :layout => true
+      render template: "test/basic", layout: true
     end
 
     def with_layout_false
-      render :template => "test/basic", :layout => false
+      render template: "test/basic", layout: false
     end
 
     def with_layout_nil
-      render :template => "test/basic", :layout => nil
+      render template: "test/basic", layout: nil
     end
 
     def with_custom_layout
-      render :template => "test/basic", :layout => "greetings"
+      render template: "test/basic", layout: "greetings"
     end
   end
 
   class TestWithLayout < Rack::TestCase
     test "rendering with implicit layout" do
       with_routing do |set|
-        set.draw { ActiveSupport::Deprecation.silence { get ':controller', :action => :index } }
+        set.draw { ActiveSupport::Deprecation.silence { get ":controller", action: :index } }
 
         get "/render_template/with_layout"
 
@@ -223,7 +224,7 @@ module RenderTemplate
       )]
 
       def with_forward_slash
-        render :template => "/test/basic"
+        render template: "/test/basic"
       end
     end
 
diff --git a/actionpack/test/controller/new_base/render_test.rb b/actionpack/test/controller/new_base/render_test.rb
index 1fb852a2c4..eb29203f59 100644
--- a/actionpack/test/controller/new_base/render_test.rb
+++ b/actionpack/test/controller/new_base/render_test.rb
@@ -1,4 +1,6 @@
-require 'abstract_unit'
+# frozen_string_literal: true
+
+require "abstract_unit"
 
 module Render
   class BlankRenderController < ActionController::Base
@@ -18,11 +20,11 @@ module Render
     end
 
     def access_request
-      render :action => "access_request"
+      render action: "access_request"
     end
 
     def render_action_name
-      render :action => "access_action_name"
+      render action: "access_action_name"
     end
 
     def overridden_with_own_view_paths_appended
@@ -36,9 +38,9 @@ module Render
 
     private
 
-    def secretz
-      render plain: "FAIL WHALE!"
-    end
+      def secretz
+        render plain: "FAIL WHALE!"
+      end
   end
 
   class DoubleRenderController < ActionController::Base
@@ -58,7 +60,7 @@ module Render
       with_routing do |set|
         set.draw do
           ActiveSupport::Deprecation.silence do
-            get ":controller", :action => 'index'
+            get ":controller", action: "index"
           end
         end
 
@@ -73,7 +75,7 @@ module Render
       with_routing do |set|
         set.draw do
           ActiveSupport::Deprecation.silence do
-            get ":controller", :action => 'index'
+            get ":controller", action: "index"
           end
         end
 
diff --git a/actionpack/test/controller/new_base/render_text_test.rb b/actionpack/test/controller/new_base/render_text_test.rb
deleted file mode 100644
index d4111d432c..0000000000
--- a/actionpack/test/controller/new_base/render_text_test.rb
+++ /dev/null
@@ -1,188 +0,0 @@
-require 'abstract_unit'
-
-module RenderText
-  class MinimalController < ActionController::Metal
-    include AbstractController::Rendering
-    include ActionController::Rendering
-
-    def index
-      render text: "Hello World!"
-    end
-  end
-
-  class SimpleController < ActionController::Base
-    self.view_paths = [ActionView::FixtureResolver.new]
-
-    def index
-      render text: "hello david"
-    end
-  end
-
-  class WithLayoutController < ::ApplicationController
-    self.view_paths = [ActionView::FixtureResolver.new(
-      "layouts/application.html.erb" => "<%= yield %>, I'm here!",
-      "layouts/greetings.html.erb"   => "<%= yield %>, I wish thee well.",
-      "layouts/ivar.html.erb"        => "<%= yield %>, <%= @ivar %>"
-    )]
-
-    def index
-      render text: "hello david"
-    end
-
-    def custom_code
-      render text: "hello world", status: 404
-    end
-
-    def with_custom_code_as_string
-      render text: "hello world", status: "404 Not Found"
-    end
-
-    def with_nil
-      render text: nil
-    end
-
-    def with_nil_and_status
-      render text: nil, status: 403
-    end
-
-    def with_false
-      render text: false
-    end
-
-    def with_layout_true
-      render text: "hello world", layout: true
-    end
-
-    def with_layout_false
-      render text: "hello world", layout: false
-    end
-
-    def with_layout_nil
-      render text: "hello world", layout: nil
-    end
-
-    def with_custom_layout
-      render text: "hello world", layout: "greetings"
-    end
-
-    def with_ivar_in_layout
-      @ivar = "hello world"
-      render text: "hello world", layout: "ivar"
-    end
-  end
-
-  class RenderTextTest < Rack::TestCase
-    test "rendering text from a minimal controller" do
-      ActiveSupport::Deprecation.silence do
-        get "/render_text/minimal/index"
-      end
-
-      assert_body "Hello World!"
-      assert_status 200
-    end
-
-    test "rendering text from an action with default options renders the text with the layout" do
-      with_routing do |set|
-        set.draw { ActiveSupport::Deprecation.silence { get ':controller', action: 'index' } }
-
-        ActiveSupport::Deprecation.silence do
-          get "/render_text/simple"
-        end
-
-        assert_body "hello david"
-        assert_status 200
-      end
-    end
-
-    test "rendering text from an action with default options renders the text without the layout" do
-      with_routing do |set|
-        set.draw { ActiveSupport::Deprecation.silence { get ':controller', action: 'index' } }
-
-        ActiveSupport::Deprecation.silence do
-          get "/render_text/with_layout"
-        end
-
-        assert_body "hello david"
-        assert_status 200
-      end
-    end
-
-    test "rendering text, while also providing a custom status code" do
-      ActiveSupport::Deprecation.silence do
-        get "/render_text/with_layout/custom_code"
-      end
-
-      assert_body "hello world"
-      assert_status 404
-    end
-
-    test "rendering text with nil returns an empty body" do
-      ActiveSupport::Deprecation.silence do
-        get "/render_text/with_layout/with_nil"
-      end
-
-      assert_body ""
-      assert_status 200
-    end
-
-    test "Rendering text with nil and custom status code returns an empty body and the status" do
-      ActiveSupport::Deprecation.silence do
-        get "/render_text/with_layout/with_nil_and_status"
-      end
-
-      assert_body ""
-      assert_status 403
-    end
-
-    test "rendering text with false returns the string 'false'" do
-      ActiveSupport::Deprecation.silence do
-        get "/render_text/with_layout/with_false"
-      end
-
-      assert_body "false"
-      assert_status 200
-    end
-
-    test "rendering text with layout: true" do
-      ActiveSupport::Deprecation.silence do
-        get "/render_text/with_layout/with_layout_true"
-      end
-
-      assert_body "hello world, I'm here!"
-      assert_status 200
-    end
-
-    test "rendering text with layout: 'greetings'" do
-      ActiveSupport::Deprecation.silence do
-        get "/render_text/with_layout/with_custom_layout"
-      end
-
-      assert_body "hello world, I wish thee well."
-      assert_status 200
-    end
-
-    test "rendering text with layout: false" do
-      ActiveSupport::Deprecation.silence do
-        get "/render_text/with_layout/with_layout_false"
-      end
-
-      assert_body "hello world"
-      assert_status 200
-    end
-
-    test "rendering text with layout: nil" do
-      ActiveSupport::Deprecation.silence do
-        get "/render_text/with_layout/with_layout_nil"
-      end
-
-      assert_body "hello world"
-      assert_status 200
-    end
-
-    test "rendering text displays deprecation warning" do
-      assert_deprecated do
-        get "/render_text/with_layout/with_layout_nil"
-      end
-    end
-  end
-end
diff --git a/actionpack/test/controller/new_base/render_xml_test.rb b/actionpack/test/controller/new_base/render_xml_test.rb
index b8527a943d..0dc16d64e2 100644
--- a/actionpack/test/controller/new_base/render_xml_test.rb
+++ b/actionpack/test/controller/new_base/render_xml_test.rb
@@ -1,7 +1,8 @@
-require 'abstract_unit'
+# frozen_string_literal: true
 
-module RenderXml
+require "abstract_unit"
 
+module RenderXml
   # This has no layout and it works
   class BasicController < ActionController::Base
     self.view_paths = [ActionView::FixtureResolver.new(
diff --git a/actionpack/test/controller/output_escaping_test.rb b/actionpack/test/controller/output_escaping_test.rb
index c3c549fbfc..e33a99068f 100644
--- a/actionpack/test/controller/output_escaping_test.rb
+++ b/actionpack/test/controller/output_escaping_test.rb
@@ -1,7 +1,8 @@
-require 'abstract_unit'
+# frozen_string_literal: true
 
-class OutputEscapingTest < ActiveSupport::TestCase
+require "abstract_unit"
 
+class OutputEscapingTest < ActiveSupport::TestCase
   test "escape_html shouldn't die when passed nil" do
     assert ERB::Util.h(nil).blank?
   end
@@ -13,5 +14,4 @@ class OutputEscapingTest < ActiveSupport::TestCase
   test "escapeHTML shouldn't touch explicitly safe strings" do
     assert_equal "<", ERB::Util.h("<".html_safe)
   end
-
 end
diff --git a/actionpack/test/controller/parameter_encoding_test.rb b/actionpack/test/controller/parameter_encoding_test.rb
new file mode 100644
index 0000000000..e2194e8974
--- /dev/null
+++ b/actionpack/test/controller/parameter_encoding_test.rb
@@ -0,0 +1,52 @@
+# frozen_string_literal: true
+
+require "abstract_unit"
+
+class ParameterEncodingController < ActionController::Base
+  skip_parameter_encoding :test_bar
+  skip_parameter_encoding :test_all_values_encoding
+
+  def test_foo
+    render body: params[:foo].encoding
+  end
+
+  def test_bar
+    render body: params[:bar].encoding
+  end
+
+  def test_all_values_encoding
+    render body: ::JSON.dump(params.values.map(&:encoding).map(&:name))
+  end
+end
+
+class ParameterEncodingTest < ActionController::TestCase
+  tests ParameterEncodingController
+
+  test "properly transcodes UTF8 parameters into declared encodings" do
+    post :test_foo, params: { "foo" => "foo", "bar" => "bar", "baz" => "baz" }
+
+    assert_response :success
+    assert_equal "UTF-8", @response.body
+  end
+
+  test "properly encodes ASCII_8BIT parameters into binary" do
+    post :test_bar, params: { "foo" => "foo", "bar" => "bar", "baz" => "baz" }
+
+    assert_response :success
+    assert_equal "ASCII-8BIT", @response.body
+  end
+
+  test "properly encodes all ASCII_8BIT parameters into binary" do
+    post :test_all_values_encoding, params: { "foo" => "foo", "bar" => "bar", "baz" => "baz" }
+
+    assert_response :success
+    assert_equal ["ASCII-8BIT"], JSON.parse(@response.body).uniq
+  end
+
+  test "does not raise an error when passed a param declared as ASCII-8BIT that contains invalid bytes" do
+    get :test_bar, params: { "bar" => URI.parser.escape("bar\xE2baz".b) }
+
+    assert_response :success
+    assert_equal "ASCII-8BIT", @response.body
+  end
+end
diff --git a/actionpack/test/controller/parameters/accessors_test.rb b/actionpack/test/controller/parameters/accessors_test.rb
index 17c62dc3fe..154430d4b0 100644
--- a/actionpack/test/controller/parameters/accessors_test.rb
+++ b/actionpack/test/controller/parameters/accessors_test.rb
@@ -1,6 +1,8 @@
-require 'abstract_unit'
-require 'action_controller/metal/strong_parameters'
-require 'active_support/core_ext/hash/transform_values'
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "action_controller/metal/strong_parameters"
+require "active_support/core_ext/hash/transform_values"
 
 class ParametersAccessorsTest < ActiveSupport::TestCase
   setup do
@@ -8,12 +10,12 @@ class ParametersAccessorsTest < ActiveSupport::TestCase
 
     @params = ActionController::Parameters.new(
       person: {
-        age: '32',
+        age: "32",
         name: {
-          first: 'David',
-          last: 'Heinemeier Hansson'
+          first: "David",
+          last: "Heinemeier Hansson"
         },
-        addresses: [{city: 'Chicago', state: 'Illinois'}]
+        addresses: [{ city: "Chicago", state: "Illinois" }]
       }
     )
   end
@@ -35,6 +37,11 @@ class ParametersAccessorsTest < ActiveSupport::TestCase
     assert @params.as_json.key? "person"
   end
 
+  test "to_s returns the string representation of the parameters hash" do
+    assert_equal '{"person"=>{"age"=>"32", "name"=>{"first"=>"David", "last"=>"Heinemeier Hansson"}, ' \
+      '"addresses"=>[{"city"=>"Chicago", "state"=>"Illinois"}]}}', @params.to_s
+  end
+
   test "each carries permitted status" do
     @params.permit!
     @params.each { |key, value| assert(value.permitted?) if key == "person" }
@@ -44,6 +51,14 @@ class ParametersAccessorsTest < ActiveSupport::TestCase
     @params.each { |key, value| assert_not(value.permitted?) if key == "person" }
   end
 
+  test "each returns key,value array for block with arity 1" do
+    @params.each do |arg|
+      assert_kind_of Array, arg
+      assert_equal "person", arg[0]
+      assert_kind_of ActionController::Parameters, arg[1]
+    end
+  end
+
   test "each_pair carries permitted status" do
     @params.permit!
     @params.each_pair { |key, value| assert(value.permitted?) if key == "person" }
@@ -53,6 +68,23 @@ class ParametersAccessorsTest < ActiveSupport::TestCase
     @params.each_pair { |key, value| assert_not(value.permitted?) if key == "person" }
   end
 
+  test "each_pair returns key,value array for block with arity 1" do
+    @params.each_pair do |arg|
+      assert_kind_of Array, arg
+      assert_equal "person", arg[0]
+      assert_kind_of ActionController::Parameters, arg[1]
+    end
+  end
+
+  test "empty? returns true when params contains no key/value pairs" do
+    params = ActionController::Parameters.new
+    assert params.empty?
+  end
+
+  test "empty? returns false when any params are present" do
+    refute @params.empty?
+  end
+
   test "except retains permitted status" do
     @params.permit!
     assert @params.except(:person).permitted?
@@ -75,6 +107,45 @@ class ParametersAccessorsTest < ActiveSupport::TestCase
     assert_not @params[:person].fetch(:name).permitted?
   end
 
+  test "has_key? returns true if the given key is present in the params" do
+    assert @params.has_key?(:person)
+  end
+
+  test "has_key? returns false if the given key is not present in the params" do
+    refute @params.has_key?(:address)
+  end
+
+  test "has_value? returns true if the given value is present in the params" do
+    params = ActionController::Parameters.new(city: "Chicago", state: "Illinois")
+    assert params.has_value?("Chicago")
+  end
+
+  test "has_value? returns false if the given value is not present in the params" do
+    params = ActionController::Parameters.new(city: "Chicago", state: "Illinois")
+    refute params.has_value?("New York")
+  end
+
+  test "include? returns true if the given key is present in the params" do
+    assert @params.include?(:person)
+  end
+
+  test "include? returns false if the given key is not present in the params" do
+    refute @params.include?(:address)
+  end
+
+  test "key? returns true if the given key is present in the params" do
+    assert @params.key?(:person)
+  end
+
+  test "key? returns false if the given key is not present in the params" do
+    refute @params.key?(:address)
+  end
+
+  test "keys returns an array of the keys of the params" do
+    assert_equal ["person"], @params.keys
+    assert_equal ["age", "name", "addresses"], @params[:person].keys
+  end
+
   test "reject retains permitted status" do
     assert_not @params.reject { |k| k == "person" }.permitted?
   end
@@ -120,6 +191,21 @@ class ParametersAccessorsTest < ActiveSupport::TestCase
     assert_not @params.transform_values { |v| v }.permitted?
   end
 
+  test "value? returns true if the given value is present in the params" do
+    params = ActionController::Parameters.new(city: "Chicago", state: "Illinois")
+    assert params.value?("Chicago")
+  end
+
+  test "value? returns false if the given value is not present in the params" do
+    params = ActionController::Parameters.new(city: "Chicago", state: "Illinois")
+    refute params.value?("New York")
+  end
+
+  test "values returns an array of the values of the params" do
+    params = ActionController::Parameters.new(city: "Chicago", state: "Illinois")
+    assert_equal ["Chicago", "Illinois"], params.values
+  end
+
   test "values_at retains permitted status" do
     @params.permit!
     assert @params.values_at(:person).first.permitted?
@@ -131,14 +217,6 @@ class ParametersAccessorsTest < ActiveSupport::TestCase
     assert_not @params[:person].values_at(:name).first.permitted?
   end
 
-  test "equality with a hash is deprecated" do
-    hash1 = { foo: :bar }
-    params1 = ActionController::Parameters.new(hash1)
-    assert_deprecated("will be removed in Rails 5.1") do
-      assert(params1 == hash1)
-    end
-  end
-
   test "is equal to Parameters instance with same params" do
     params1 = ActionController::Parameters.new(a: 1, b: 2)
     params2 = ActionController::Parameters.new(a: 1, b: 2)
@@ -158,7 +236,7 @@ class ParametersAccessorsTest < ActiveSupport::TestCase
     assert(params2 == params1)
   end
 
-  test 'is not equal to an unpermitted Parameters instance with same params' do
+  test "is not equal to an unpermitted Parameters instance with same params" do
     params1 = ActionController::Parameters.new(a: 1).permit(:a)
     params2 = ActionController::Parameters.new(a: 1)
     assert(params1 != params2)
@@ -173,7 +251,7 @@ class ParametersAccessorsTest < ActiveSupport::TestCase
   end
 
   test "equality with simple types works" do
-    assert(@params != 'Hello')
+    assert(@params != "Hello")
     assert(@params != 42)
     assert(@params != false)
   end
diff --git a/actionpack/test/controller/parameters/always_permitted_parameters_test.rb b/actionpack/test/controller/parameters/always_permitted_parameters_test.rb
index c5bfb10b53..1e8b71d789 100644
--- a/actionpack/test/controller/parameters/always_permitted_parameters_test.rb
+++ b/actionpack/test/controller/parameters/always_permitted_parameters_test.rb
@@ -1,5 +1,7 @@
-require 'abstract_unit'
-require 'action_controller/metal/strong_parameters'
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "action_controller/metal/strong_parameters"
 
 class AlwaysPermittedParametersTest < ActiveSupport::TestCase
   def setup
@@ -19,10 +21,9 @@ class AlwaysPermittedParametersTest < ActiveSupport::TestCase
   end
 
   test "permits parameters that are whitelisted" do
-    params = ActionController::Parameters.new({
+    params = ActionController::Parameters.new(
       book: { pages: 65 },
-      format: "json"
-    })
+      format: "json")
     permitted = params.permit book: [:pages]
     assert permitted.permitted?
   end
diff --git a/actionpack/test/controller/parameters/dup_test.rb b/actionpack/test/controller/parameters/dup_test.rb
new file mode 100644
index 0000000000..f5833aff46
--- /dev/null
+++ b/actionpack/test/controller/parameters/dup_test.rb
@@ -0,0 +1,67 @@
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "action_controller/metal/strong_parameters"
+require "active_support/core_ext/object/deep_dup"
+
+class ParametersDupTest < ActiveSupport::TestCase
+  setup do
+    ActionController::Parameters.permit_all_parameters = false
+
+    @params = ActionController::Parameters.new(
+      person: {
+        age: "32",
+        name: {
+          first: "David",
+          last: "Heinemeier Hansson"
+        },
+        addresses: [{ city: "Chicago", state: "Illinois" }]
+      }
+    )
+  end
+
+  test "a duplicate maintains the original's permitted status" do
+    @params.permit!
+    dupped_params = @params.dup
+    assert dupped_params.permitted?
+  end
+
+  test "a duplicate maintains the original's parameters" do
+    @params.permit!
+    dupped_params = @params.dup
+    assert_equal @params.to_h, dupped_params.to_h
+  end
+
+  test "changes to a duplicate's parameters do not affect the original" do
+    dupped_params = @params.dup
+    dupped_params.delete(:person)
+    assert_not_equal @params, dupped_params
+  end
+
+  test "changes to a duplicate's permitted status do not affect the original" do
+    dupped_params = @params.dup
+    dupped_params.permit!
+    assert_not_equal @params, dupped_params
+  end
+
+  test "deep_dup content" do
+    dupped_params = @params.deep_dup
+    dupped_params[:person][:age] = "45"
+    dupped_params[:person][:addresses].clear
+
+    assert_not_equal @params[:person][:age], dupped_params[:person][:age]
+    assert_not_equal @params[:person][:addresses], dupped_params[:person][:addresses]
+  end
+
+  test "deep_dup @permitted" do
+    dupped_params = @params.deep_dup
+    dupped_params.permit!
+
+    assert_not @params.permitted?
+  end
+
+  test "deep_dup @permitted is being copied" do
+    @params.permit!
+    assert @params.deep_dup.permitted?
+  end
+end
diff --git a/actionpack/test/controller/parameters/log_on_unpermitted_params_test.rb b/actionpack/test/controller/parameters/log_on_unpermitted_params_test.rb
index 9ce04b9aeb..fc9229ca1d 100644
--- a/actionpack/test/controller/parameters/log_on_unpermitted_params_test.rb
+++ b/actionpack/test/controller/parameters/log_on_unpermitted_params_test.rb
@@ -1,5 +1,7 @@
-require 'abstract_unit'
-require 'action_controller/metal/strong_parameters'
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "action_controller/metal/strong_parameters"
 
 class LogOnUnpermittedParamsTest < ActiveSupport::TestCase
   def setup
@@ -11,62 +13,58 @@ class LogOnUnpermittedParamsTest < ActiveSupport::TestCase
   end
 
   test "logs on unexpected param" do
-    params = ActionController::Parameters.new({
+    params = ActionController::Parameters.new(
       book: { pages: 65 },
-      fishing: "Turnips"
-    })
+      fishing: "Turnips")
 
-    assert_logged("Unpermitted parameter: fishing") do
+    assert_logged("Unpermitted parameter: :fishing") do
       params.permit(book: [:pages])
     end
   end
 
   test "logs on unexpected params" do
-    params = ActionController::Parameters.new({
+    params = ActionController::Parameters.new(
       book: { pages: 65 },
       fishing: "Turnips",
-      car: "Mersedes"
-    })
+      car: "Mersedes")
 
-    assert_logged("Unpermitted parameters: fishing, car") do
+    assert_logged("Unpermitted parameters: :fishing, :car") do
       params.permit(book: [:pages])
     end
   end
 
   test "logs on unexpected nested param" do
-    params = ActionController::Parameters.new({
-      book: { pages: 65, title: "Green Cats and where to find then." }
-    })
+    params = ActionController::Parameters.new(
+      book: { pages: 65, title: "Green Cats and where to find then." })
 
-    assert_logged("Unpermitted parameter: title") do
+    assert_logged("Unpermitted parameter: :title") do
       params.permit(book: [:pages])
     end
   end
 
   test "logs on unexpected nested params" do
-    params = ActionController::Parameters.new({
-      book: { pages: 65, title: "Green Cats and where to find then.", author: "G. A. Dog" }
-    })
+    params = ActionController::Parameters.new(
+      book: { pages: 65, title: "Green Cats and where to find then.", author: "G. A. Dog" })
 
-    assert_logged("Unpermitted parameters: title, author") do
+    assert_logged("Unpermitted parameters: :title, :author") do
       params.permit(book: [:pages])
     end
   end
 
   private
 
-  def assert_logged(message)
-    old_logger = ActionController::Base.logger
-    log = StringIO.new
-    ActionController::Base.logger = Logger.new(log)
+    def assert_logged(message)
+      old_logger = ActionController::Base.logger
+      log = StringIO.new
+      ActionController::Base.logger = Logger.new(log)
 
-    begin
-      yield
+      begin
+        yield
 
-      log.rewind
-      assert_match message, log.read
-    ensure
-      ActionController::Base.logger = old_logger
+        log.rewind
+        assert_match message, log.read
+      ensure
+        ActionController::Base.logger = old_logger
+      end
     end
-  end
 end
diff --git a/actionpack/test/controller/parameters/multi_parameter_attributes_test.rb b/actionpack/test/controller/parameters/multi_parameter_attributes_test.rb
index 15338059bc..dcf848a620 100644
--- a/actionpack/test/controller/parameters/multi_parameter_attributes_test.rb
+++ b/actionpack/test/controller/parameters/multi_parameter_attributes_test.rb
@@ -1,9 +1,11 @@
-require 'abstract_unit'
-require 'action_controller/metal/strong_parameters'
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "action_controller/metal/strong_parameters"
 
 class MultiParameterAttributesTest < ActiveSupport::TestCase
   test "permitted multi-parameter attribute keys" do
-    params = ActionController::Parameters.new({
+    params = ActionController::Parameters.new(
       book: {
         "shipped_at(1i)"   => "2012",
         "shipped_at(2i)"   => "3",
@@ -15,8 +17,7 @@ class MultiParameterAttributesTest < ActiveSupport::TestCase
         "published_at(3i)" => "5",
         "price(1)"         => "R$",
         "price(2f)"        => "2.02"
-      }
-    })
+      })
 
     permitted = params.permit book: [ :shipped_at, :price ]
 
diff --git a/actionpack/test/controller/parameters/mutators_test.rb b/actionpack/test/controller/parameters/mutators_test.rb
index 744d8664be..49dede03c2 100644
--- a/actionpack/test/controller/parameters/mutators_test.rb
+++ b/actionpack/test/controller/parameters/mutators_test.rb
@@ -1,17 +1,19 @@
-require 'abstract_unit'
-require 'action_controller/metal/strong_parameters'
-require 'active_support/core_ext/hash/transform_values'
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "action_controller/metal/strong_parameters"
+require "active_support/core_ext/hash/transform_values"
 
 class ParametersMutatorsTest < ActiveSupport::TestCase
   setup do
     @params = ActionController::Parameters.new(
       person: {
-        age: '32',
+        age: "32",
         name: {
-          first: 'David',
-          last: 'Heinemeier Hansson'
+          first: "David",
+          last: "Heinemeier Hansson"
         },
-        addresses: [{city: 'Chicago', state: 'Illinois'}]
+        addresses: [{ city: "Chicago", state: "Illinois" }]
       }
     )
   end
@@ -25,6 +27,27 @@ class ParametersMutatorsTest < ActiveSupport::TestCase
     assert_not @params.delete(:person).permitted?
   end
 
+  test "delete returns the value when the key is present" do
+    assert_equal "32", @params[:person].delete(:age)
+  end
+
+  test "delete removes the entry when the key present" do
+    @params[:person].delete(:age)
+    assert_not @params[:person].key?(:age)
+  end
+
+  test "delete returns nil when the key is not present" do
+    assert_nil @params[:person].delete(:first_name)
+  end
+
+  test "delete returns the value of the given block when the key is not present" do
+    assert_equal "David", @params[:person].delete(:first_name) { "David" }
+  end
+
+  test "delete yields the key to the given block when the key is not present" do
+    assert_equal "first_name: David", @params[:person].delete(:first_name) { |k| "#{k}: David" }
+  end
+
   test "delete_if retains permitted status" do
     @params.permit!
     assert @params.delete_if { |k| k == "person" }.permitted?
@@ -45,11 +68,11 @@ class ParametersMutatorsTest < ActiveSupport::TestCase
 
   test "keep_if retains permitted status" do
     @params.permit!
-    assert @params.keep_if { |k,v| k == "person" }.permitted?
+    assert @params.keep_if { |k, v| k == "person" }.permitted?
   end
 
   test "keep_if retains unpermitted status" do
-    assert_not @params.keep_if { |k,v| k == "person" }.permitted?
+    assert_not @params.keep_if { |k, v| k == "person" }.permitted?
   end
 
   test "reject! retains permitted status" do
diff --git a/actionpack/test/controller/parameters/nested_parameters_test.rb b/actionpack/test/controller/parameters/nested_parameters_permit_test.rb
index 7151a8567c..c9fcc483ee 100644
--- a/actionpack/test/controller/parameters/nested_parameters_test.rb
+++ b/actionpack/test/controller/parameters/nested_parameters_permit_test.rb
@@ -1,13 +1,15 @@
-require 'abstract_unit'
-require 'action_controller/metal/strong_parameters'
+# frozen_string_literal: true
 
-class NestedParametersTest < ActiveSupport::TestCase
+require "abstract_unit"
+require "action_controller/metal/strong_parameters"
+
+class NestedParametersPermitTest < ActiveSupport::TestCase
   def assert_filtered_out(params, key)
     assert !params.has_key?(key), "key #{key.inspect} has not been filtered out"
   end
 
   test "permitted nested parameters" do
-    params = ActionController::Parameters.new({
+    params = ActionController::Parameters.new(
       book: {
         title: "Romeo and Juliet",
         authors: [{
@@ -23,11 +25,10 @@ class NestedParametersTest < ActiveSupport::TestCase
           genre: "Tragedy"
         },
         id: {
-          isbn: 'x'
+          isbn: "x"
         }
       },
-      magazine: "Mjallo!"
-    })
+      magazine: "Mjallo!")
 
     permitted = params.permit book: [ :title, { authors: [ :name ] }, { details: :pages }, :id ]
 
@@ -45,74 +46,69 @@ class NestedParametersTest < ActiveSupport::TestCase
   end
 
   test "permitted nested parameters with a string or a symbol as a key" do
-    params = ActionController::Parameters.new({
+    params = ActionController::Parameters.new(
       book: {
-        'authors' => [
-          { name: 'William Shakespeare', born: '1564-04-26' },
-          { name: 'Christopher Marlowe' }
+        "authors" => [
+          { name: "William Shakespeare", born: "1564-04-26" },
+          { name: "Christopher Marlowe" }
         ]
-      }
-    })
+      })
 
-    permitted = params.permit book: [ { 'authors' => [ :name ] } ]
+    permitted = params.permit book: [ { "authors" => [ :name ] } ]
 
-    assert_equal 'William Shakespeare', permitted[:book]['authors'][0][:name]
-    assert_equal 'William Shakespeare', permitted[:book][:authors][0][:name]
-    assert_equal 'Christopher Marlowe', permitted[:book]['authors'][1][:name]
-    assert_equal 'Christopher Marlowe', permitted[:book][:authors][1][:name]
+    assert_equal "William Shakespeare", permitted[:book]["authors"][0][:name]
+    assert_equal "William Shakespeare", permitted[:book][:authors][0][:name]
+    assert_equal "Christopher Marlowe", permitted[:book]["authors"][1][:name]
+    assert_equal "Christopher Marlowe", permitted[:book][:authors][1][:name]
 
     permitted = params.permit book: [ { authors: [ :name ] } ]
 
-    assert_equal 'William Shakespeare', permitted[:book]['authors'][0][:name]
-    assert_equal 'William Shakespeare', permitted[:book][:authors][0][:name]
-    assert_equal 'Christopher Marlowe', permitted[:book]['authors'][1][:name]
-    assert_equal 'Christopher Marlowe', permitted[:book][:authors][1][:name]
+    assert_equal "William Shakespeare", permitted[:book]["authors"][0][:name]
+    assert_equal "William Shakespeare", permitted[:book][:authors][0][:name]
+    assert_equal "Christopher Marlowe", permitted[:book]["authors"][1][:name]
+    assert_equal "Christopher Marlowe", permitted[:book][:authors][1][:name]
   end
 
   test "nested arrays with strings" do
-    params = ActionController::Parameters.new({
+    params = ActionController::Parameters.new(
       book: {
         genres: ["Tragedy"]
-      }
-    })
+      })
 
-    permitted = params.permit book: {genres: []}
+    permitted = params.permit book: { genres: [] }
     assert_equal ["Tragedy"], permitted[:book][:genres]
   end
 
   test "permit may specify symbols or strings" do
-    params = ActionController::Parameters.new({
+    params = ActionController::Parameters.new(
       book: {
         title: "Romeo and Juliet",
         author: "William Shakespeare"
       },
-      magazine: "Shakespeare Today"
-    })
+      magazine: "Shakespeare Today")
 
-    permitted = params.permit({book: ["title", :author]}, "magazine")
+    permitted = params.permit({ book: ["title", :author] }, "magazine")
     assert_equal "Romeo and Juliet", permitted[:book][:title]
     assert_equal "William Shakespeare", permitted[:book][:author]
     assert_equal "Shakespeare Today", permitted[:magazine]
   end
 
   test "nested array with strings that should be hashes" do
-    params = ActionController::Parameters.new({
+    params = ActionController::Parameters.new(
       book: {
         genres: ["Tragedy"]
-      }
-    })
+      })
 
     permitted = params.permit book: { genres: :type }
     assert_empty permitted[:book][:genres]
   end
 
   test "nested array with strings that should be hashes and additional values" do
-    params = ActionController::Parameters.new({
+    params = ActionController::Parameters.new(
       book: {
         title: "Romeo and Juliet",
         genres: ["Tragedy"]
-      }
-    })
+      })
 
     permitted = params.permit book: [ :title, { genres: :type } ]
     assert_equal "Romeo and Juliet", permitted[:book][:title]
@@ -120,66 +116,67 @@ class NestedParametersTest < ActiveSupport::TestCase
   end
 
   test "nested string that should be a hash" do
-    params = ActionController::Parameters.new({
+    params = ActionController::Parameters.new(
       book: {
         genre: "Tragedy"
-      }
-    })
+      })
 
     permitted = params.permit book: { genre: :type }
     assert_nil permitted[:book][:genre]
   end
 
   test "fields_for-style nested params" do
-    params = ActionController::Parameters.new({
+    params = ActionController::Parameters.new(
       book: {
         authors_attributes: {
-          :'0' => { name: 'William Shakespeare', age_of_death: '52' },
-          :'1' => { name: 'Unattributed Assistant' },
-          :'2' => { name: %w(injected names) }
+          '0': { name: "William Shakespeare", age_of_death: "52" },
+          '1': { name: "Unattributed Assistant" },
+          '2': { name: %w(injected names) }
         }
-      }
-    })
+      })
     permitted = params.permit book: { authors_attributes: [ :name ] }
 
-    assert_not_nil permitted[:book][:authors_attributes]['0']
-    assert_not_nil permitted[:book][:authors_attributes]['1']
-    assert_empty permitted[:book][:authors_attributes]['2']
-    assert_equal 'William Shakespeare', permitted[:book][:authors_attributes]['0'][:name]
-    assert_equal 'Unattributed Assistant', permitted[:book][:authors_attributes]['1'][:name]
+    assert_not_nil permitted[:book][:authors_attributes]["0"]
+    assert_not_nil permitted[:book][:authors_attributes]["1"]
+    assert_empty permitted[:book][:authors_attributes]["2"]
+    assert_equal "William Shakespeare", permitted[:book][:authors_attributes]["0"][:name]
+    assert_equal "Unattributed Assistant", permitted[:book][:authors_attributes]["1"][:name]
+
+    assert_equal(
+      { "book" => { "authors_attributes" => { "0" => { "name" => "William Shakespeare" }, "1" => { "name" => "Unattributed Assistant" }, "2" => {} } } },
+      permitted.to_h
+    )
 
-    assert_filtered_out permitted[:book][:authors_attributes]['0'], :age_of_death
+    assert_filtered_out permitted[:book][:authors_attributes]["0"], :age_of_death
   end
 
   test "fields_for-style nested params with negative numbers" do
-    params = ActionController::Parameters.new({
+    params = ActionController::Parameters.new(
       book: {
         authors_attributes: {
-          :'-1' => { name: 'William Shakespeare', age_of_death: '52' },
-          :'-2' => { name: 'Unattributed Assistant' }
+          '-1': { name: "William Shakespeare", age_of_death: "52" },
+          '-2': { name: "Unattributed Assistant" }
         }
-      }
-    })
+      })
     permitted = params.permit book: { authors_attributes: [:name] }
 
-    assert_not_nil permitted[:book][:authors_attributes]['-1']
-    assert_not_nil permitted[:book][:authors_attributes]['-2']
-    assert_equal 'William Shakespeare', permitted[:book][:authors_attributes]['-1'][:name]
-    assert_equal 'Unattributed Assistant', permitted[:book][:authors_attributes]['-2'][:name]
+    assert_not_nil permitted[:book][:authors_attributes]["-1"]
+    assert_not_nil permitted[:book][:authors_attributes]["-2"]
+    assert_equal "William Shakespeare", permitted[:book][:authors_attributes]["-1"][:name]
+    assert_equal "Unattributed Assistant", permitted[:book][:authors_attributes]["-2"][:name]
 
-    assert_filtered_out permitted[:book][:authors_attributes]['-1'], :age_of_death
+    assert_filtered_out permitted[:book][:authors_attributes]["-1"], :age_of_death
   end
 
   test "nested number as key" do
-    params = ActionController::Parameters.new({
+    params = ActionController::Parameters.new(
       product: {
         properties: {
-          '0' => "prop0",
-          '1' => "prop1"
+          "0" => "prop0",
+          "1" => "prop1"
         }
-      }
-    })
-    params = params.require(:product).permit(:properties => ["0"])
+      })
+    params = params.require(:product).permit(properties: ["0"])
     assert_not_nil        params[:properties]["0"]
     assert_nil            params[:properties]["1"]
     assert_equal "prop0", params[:properties]["0"]
diff --git a/actionpack/test/controller/parameters/parameters_permit_test.rb b/actionpack/test/controller/parameters/parameters_permit_test.rb
index b75eb0e3bf..e9b94b056b 100644
--- a/actionpack/test/controller/parameters/parameters_permit_test.rb
+++ b/actionpack/test/controller/parameters/parameters_permit_test.rb
@@ -1,6 +1,8 @@
-require 'abstract_unit'
-require 'action_dispatch/http/upload'
-require 'action_controller/metal/strong_parameters'
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "action_dispatch/http/upload"
+require "action_controller/metal/strong_parameters"
 
 class ParametersPermitTest < ActiveSupport::TestCase
   def assert_filtered_out(params, key)
@@ -10,25 +12,25 @@ class ParametersPermitTest < ActiveSupport::TestCase
   setup do
     @params = ActionController::Parameters.new(
       person: {
-        age: '32',
+        age: "32",
         name: {
-          first: 'David',
-          last: 'Heinemeier Hansson'
+          first: "David",
+          last: "Heinemeier Hansson"
         },
-        addresses: [{city: 'Chicago', state: 'Illinois'}]
+        addresses: [{ city: "Chicago", state: "Illinois" }]
       }
     )
 
     @struct_fields = []
     %w(0 1 12).each do |number|
-      ['', 'i', 'f'].each do |suffix|
+      ["", "i", "f"].each do |suffix|
         @struct_fields << "sf(#{number}#{suffix})"
       end
     end
   end
 
-  def walk_permitted params
-    params.each do |k,v|
+  def walk_permitted(params)
+    params.each do |k, v|
       case v
       when ActionController::Parameters
         walk_permitted v
@@ -38,26 +40,26 @@ class ParametersPermitTest < ActiveSupport::TestCase
     end
   end
 
-  test 'iteration should not impact permit' do
-    hash = {"foo"=>{"bar"=>{"0"=>{"baz"=>"hello", "zot"=>"1"}}}}
+  test "iteration should not impact permit" do
+    hash = { "foo" => { "bar" => { "0" => { "baz" => "hello", "zot" => "1" } } } }
     params = ActionController::Parameters.new(hash)
 
     walk_permitted params
 
     sanitized = params[:foo].permit(bar: [:baz])
-    assert_equal({"0"=>{"baz"=>"hello"}}, sanitized[:bar].to_unsafe_h)
+    assert_equal({ "0" => { "baz" => "hello" } }, sanitized[:bar].to_unsafe_h)
   end
 
-  test 'if nothing is permitted, the hash becomes empty' do
-    params = ActionController::Parameters.new(id: '1234')
+  test "if nothing is permitted, the hash becomes empty" do
+    params = ActionController::Parameters.new(id: "1234")
     permitted = params.permit
     assert permitted.permitted?
     assert permitted.empty?
   end
 
-  test 'key: permitted scalar values' do
-    values  = ['a', :a, nil]
-    values += [0, 1.0, 2**128, BigDecimal.new(1)]
+  test "key: permitted scalar values" do
+    values  = ["a", :a, nil]
+    values += [0, 1.0, 2**128, BigDecimal(1)]
     values += [true, false]
     values += [Date.today, Time.now, DateTime.now]
     values += [STDOUT, StringIO.new, ActionDispatch::Http::UploadedFile.new(tempfile: __FILE__),
@@ -66,25 +68,33 @@ class ParametersPermitTest < ActiveSupport::TestCase
     values.each do |value|
       params = ActionController::Parameters.new(id: value)
       permitted = params.permit(:id)
-      assert_equal value, permitted[:id]
+      if value.nil?
+        assert_nil permitted[:id]
+      else
+        assert_equal value, permitted[:id]
+      end
 
       @struct_fields.each do |sf|
         params = ActionController::Parameters.new(sf => value)
         permitted = params.permit(:sf)
-        assert_equal value, permitted[sf]
+        if value.nil?
+          assert_nil permitted[sf]
+        else
+          assert_equal value, permitted[sf]
+        end
       end
     end
   end
 
-  test 'key: unknown keys are filtered out' do
-    params = ActionController::Parameters.new(id: '1234', injected: 'injected')
+  test "key: unknown keys are filtered out" do
+    params = ActionController::Parameters.new(id: "1234", injected: "injected")
     permitted = params.permit(:id)
-    assert_equal '1234', permitted[:id]
+    assert_equal "1234", permitted[:id]
     assert_filtered_out permitted, :injected
   end
 
-  test 'key: arrays are filtered out' do
-    [[], [1], ['1']].each do |array|
+  test "key: arrays are filtered out" do
+    [[], [1], ["1"]].each do |array|
       params = ActionController::Parameters.new(id: array)
       permitted = params.permit(:id)
       assert_filtered_out permitted, :id
@@ -97,8 +107,8 @@ class ParametersPermitTest < ActiveSupport::TestCase
     end
   end
 
-  test 'key: hashes are filtered out' do
-    [{}, {foo: 1}, {foo: 'bar'}].each do |hash|
+  test "key: hashes are filtered out" do
+    [{}, { foo: 1 }, { foo: "bar" }].each do |hash|
       params = ActionController::Parameters.new(id: hash)
       permitted = params.permit(:id)
       assert_filtered_out permitted, :id
@@ -111,7 +121,7 @@ class ParametersPermitTest < ActiveSupport::TestCase
     end
   end
 
-  test 'key: non-permitted scalar values are filtered out' do
+  test "key: non-permitted scalar values are filtered out" do
     params = ActionController::Parameters.new(id: Object.new)
     permitted = params.permit(:id)
     assert_filtered_out permitted, :id
@@ -123,51 +133,84 @@ class ParametersPermitTest < ActiveSupport::TestCase
     end
   end
 
-  test 'key: it is not assigned if not present in params' do
-    params = ActionController::Parameters.new(name: 'Joe')
+  test "key: it is not assigned if not present in params" do
+    params = ActionController::Parameters.new(name: "Joe")
     permitted = params.permit(:id)
     assert !permitted.has_key?(:id)
   end
 
-  test 'key to empty array: empty arrays pass' do
+  test "key to empty array: empty arrays pass" do
     params = ActionController::Parameters.new(id: [])
     permitted = params.permit(id: [])
     assert_equal [], permitted[:id]
   end
 
-  test 'do not break params filtering on nil values' do
+  test "do not break params filtering on nil values" do
     params = ActionController::Parameters.new(a: 1, b: [1, 2, 3], c: nil)
 
     permitted = params.permit(:a, c: [], b: [])
     assert_equal 1, permitted[:a]
     assert_equal [1, 2, 3], permitted[:b]
-    assert_equal nil, permitted[:c]
+    assert_nil permitted[:c]
   end
 
-  test 'key to empty array: arrays of permitted scalars pass' do
-    [['foo'], [1], ['foo', 'bar'], [1, 2, 3]].each do |array|
+  test "key to empty array: arrays of permitted scalars pass" do
+    [["foo"], [1], ["foo", "bar"], [1, 2, 3]].each do |array|
       params = ActionController::Parameters.new(id: array)
       permitted = params.permit(id: [])
       assert_equal array, permitted[:id]
     end
   end
 
-  test 'key to empty array: permitted scalar values do not pass' do
-    ['foo', 1].each do |permitted_scalar|
+  test "key to empty array: permitted scalar values do not pass" do
+    ["foo", 1].each do |permitted_scalar|
       params = ActionController::Parameters.new(id: permitted_scalar)
       permitted = params.permit(id: [])
       assert_filtered_out permitted, :id
     end
   end
 
-  test 'key to empty array: arrays of non-permitted scalar do not pass' do
-    [[Object.new], [[]], [[1]], [{}], [{id: '1'}]].each do |non_permitted_scalar|
+  test "key to empty array: arrays of non-permitted scalar do not pass" do
+    [[Object.new], [[]], [[1]], [{}], [{ id: "1" }]].each do |non_permitted_scalar|
       params = ActionController::Parameters.new(id: non_permitted_scalar)
       permitted = params.permit(id: [])
       assert_filtered_out permitted, :id
     end
   end
 
+  test "key to empty hash: arbitrary hashes are permitted" do
+    params = ActionController::Parameters.new(
+      username: "fxn",
+      preferences: {
+        scheme: "Marazul",
+        font: {
+          name: "Source Code Pro",
+          size: 12
+        },
+        tabstops:   [4, 8, 12, 16],
+        suspicious: [true, Object.new, false, /yo!/],
+        dubious:    [{ a: :a, b: /wtf!/ }, { c: :c }],
+        injected:   Object.new
+      },
+      hacked: 1 # not a hash
+    )
+
+    permitted = params.permit(:username, preferences: {}, hacked: {})
+
+    assert_equal "fxn",             permitted[:username]
+    assert_equal "Marazul",         permitted[:preferences][:scheme]
+    assert_equal "Source Code Pro", permitted[:preferences][:font][:name]
+    assert_equal 12,                permitted[:preferences][:font][:size]
+    assert_equal [4, 8, 12, 16],    permitted[:preferences][:tabstops]
+    assert_equal [true, false],     permitted[:preferences][:suspicious]
+    assert_equal :a,                permitted[:preferences][:dubious][0][:a]
+    assert_equal :c,                permitted[:preferences][:dubious][1][:c]
+
+    assert_filtered_out permitted[:preferences][:dubious][0], :b
+    assert_filtered_out permitted[:preferences], :injected
+    assert_filtered_out permitted, :hacked
+  end
+
   test "fetch raises ParameterMissing exception" do
     e = assert_raises(ActionController::ParameterMissing) do
       @params.fetch :foo
@@ -178,10 +221,10 @@ class ParametersPermitTest < ActiveSupport::TestCase
   test "fetch with a default value of a hash does not mutate the object" do
     params = ActionController::Parameters.new({})
     params.fetch :foo, {}
-    assert_equal nil, params[:foo]
+    assert_nil params[:foo]
   end
 
-  test 'hashes in array values get wrapped' do
+  test "hashes in array values get wrapped" do
     params = ActionController::Parameters.new(foo: [{}, {}])
     params[:foo].each do |hash|
       assert !hash.permitted?
@@ -191,7 +234,7 @@ class ParametersPermitTest < ActiveSupport::TestCase
   # Strong params has an optimization to avoid looping every time you read
   # a key whose value is an array and building a new object. We check that
   # optimization here.
-  test 'arrays are converted at most once' do
+  test "arrays are converted at most once" do
     params = ActionController::Parameters.new(foo: [{}])
     assert_same params[:foo], params[:foo]
   end
@@ -202,11 +245,11 @@ class ParametersPermitTest < ActiveSupport::TestCase
   # This test checks that if we push a hash to an array (in-place modification)
   # the cache does not get fooled, the hash is still wrapped as strong params,
   # and not permitted.
-  test 'mutated arrays are detected' do
-    params = ActionController::Parameters.new(users: [{id: 1}])
+  test "mutated arrays are detected" do
+    params = ActionController::Parameters.new(users: [{ id: 1 }])
 
     permitted = params.permit(users: [:id])
-    permitted[:users] << {injected: 1}
+    permitted[:users] << { injected: 1 }
     assert_not permitted[:users].last.permitted?
   end
 
@@ -216,11 +259,11 @@ class ParametersPermitTest < ActiveSupport::TestCase
   end
 
   test "fetch doesnt raise ParameterMissing exception if there is a default that is nil" do
-    assert_equal nil, @params.fetch(:foo, nil)
-    assert_equal nil, @params.fetch(:foo) { nil }
+    assert_nil @params.fetch(:foo, nil)
+    assert_nil @params.fetch(:foo) { nil }
   end
 
-  test 'KeyError in fetch block should not be covered up' do
+  test "KeyError in fetch block should not be covered up" do
     params = ActionController::Parameters.new
     e = assert_raises(KeyError) do
       params.fetch(:missing_key) { {}.fetch(:also_missing) }
@@ -237,6 +280,71 @@ class ParametersPermitTest < ActiveSupport::TestCase
     assert @params.merge(a: "b").permitted?
   end
 
+  test "merge with parameters" do
+    other_params = ActionController::Parameters.new(id: "1234").permit!
+    merged_params = @params.merge(other_params)
+
+    assert merged_params[:id]
+  end
+
+  test "not permitted is sticky beyond merge!" do
+    assert_not @params.merge!(a: "b").permitted?
+  end
+
+  test "permitted is sticky beyond merge!" do
+    @params.permit!
+    assert @params.merge!(a: "b").permitted?
+  end
+
+  test "merge! with parameters" do
+    other_params = ActionController::Parameters.new(id: "1234").permit!
+    @params.merge!(other_params)
+
+    assert_equal "1234", @params[:id]
+    assert_equal "32", @params[:person][:age]
+  end
+
+  test "#reverse_merge with parameters" do
+    default_params = ActionController::Parameters.new(id: "1234", person: {}).permit!
+    merged_params = @params.reverse_merge(default_params)
+
+    assert_equal "1234", merged_params[:id]
+    refute_predicate merged_params[:person], :empty?
+  end
+
+  test "#with_defaults is an alias of reverse_merge" do
+    default_params = ActionController::Parameters.new(id: "1234", person: {}).permit!
+    merged_params = @params.with_defaults(default_params)
+
+    assert_equal "1234", merged_params[:id]
+    refute_predicate merged_params[:person], :empty?
+  end
+
+  test "not permitted is sticky beyond reverse_merge" do
+    refute_predicate @params.reverse_merge(a: "b"), :permitted?
+  end
+
+  test "permitted is sticky beyond reverse_merge" do
+    @params.permit!
+    assert_predicate @params.reverse_merge(a: "b"), :permitted?
+  end
+
+  test "#reverse_merge! with parameters" do
+    default_params = ActionController::Parameters.new(id: "1234", person: {}).permit!
+    @params.reverse_merge!(default_params)
+
+    assert_equal "1234", @params[:id]
+    refute_predicate @params[:person], :empty?
+  end
+
+  test "#with_defaults! is an alias of reverse_merge!" do
+    default_params = ActionController::Parameters.new(id: "1234", person: {}).permit!
+    @params.with_defaults!(default_params)
+
+    assert_equal "1234", @params[:id]
+    refute_predicate @params[:person], :empty?
+  end
+
   test "modifying the parameters" do
     @params[:person][:hometown] = "Chicago"
     @params[:person][:family] = { brother: "Jonas" }
@@ -245,11 +353,6 @@ class ParametersPermitTest < ActiveSupport::TestCase
     assert_equal "Jonas", @params[:person][:family][:brother]
   end
 
-  test "permit state is kept on a dup" do
-    @params.permit!
-    assert_equal @params.permitted?, @params.dup.permitted?
-  end
-
   test "permit is recursive" do
     @params.permit!
     assert @params.permitted?
@@ -261,9 +364,9 @@ class ParametersPermitTest < ActiveSupport::TestCase
   test "permitted takes a default value when Parameters.permit_all_parameters is set" do
     begin
       ActionController::Parameters.permit_all_parameters = true
-      params = ActionController::Parameters.new({ person: {
+      params = ActionController::Parameters.new(person: {
         age: "32", name: { first: "David", last: "Heinemeier Hansson" }
-      }})
+      })
 
       assert params.slice(:person).permitted?
       assert params[:person][:name].permitted?
@@ -276,17 +379,17 @@ class ParametersPermitTest < ActiveSupport::TestCase
     assert_equal "32", @params[:person].permit([ :age ])[:age]
   end
 
-  test "to_h returns empty hash on unpermitted params" do
-    assert @params.to_h.is_a? ActiveSupport::HashWithIndifferentAccess
-    assert_not @params.to_h.is_a? ActionController::Parameters
-    assert @params.to_h.empty?
+  test "to_h raises UnfilteredParameters on unfiltered params" do
+    assert_raises(ActionController::UnfilteredParameters) do
+      @params.to_h
+    end
   end
 
   test "to_h returns converted hash on permitted params" do
     @params.permit!
 
-    assert @params.to_h.is_a? ActiveSupport::HashWithIndifferentAccess
-    assert_not @params.to_h.is_a? ActionController::Parameters
+    assert_instance_of ActiveSupport::HashWithIndifferentAccess, @params.to_h
+    assert_not_kind_of ActionController::Parameters, @params.to_h
   end
 
   test "to_h returns converted hash when .permit_all_parameters is set" do
@@ -294,39 +397,71 @@ class ParametersPermitTest < ActiveSupport::TestCase
       ActionController::Parameters.permit_all_parameters = true
       params = ActionController::Parameters.new(crab: "Senjougahara Hitagi")
 
-      assert params.to_h.is_a? ActiveSupport::HashWithIndifferentAccess
-      assert_not @params.to_h.is_a? ActionController::Parameters
+      assert_instance_of ActiveSupport::HashWithIndifferentAccess, params.to_h
+      assert_not_kind_of ActionController::Parameters, params.to_h
       assert_equal({ "crab" => "Senjougahara Hitagi" }, params.to_h)
     ensure
       ActionController::Parameters.permit_all_parameters = false
     end
   end
 
-  test "to_h returns always permitted parameter on unpermitted params" do
-    params = ActionController::Parameters.new(
-      controller: "users",
-      action: "create",
-      user: {
-        name: "Sengoku Nadeko"
-      }
-    )
+  test "to_hash raises UnfilteredParameters on unfiltered params" do
+    assert_raises(ActionController::UnfilteredParameters) do
+      @params.to_hash
+    end
+  end
+
+  test "to_hash returns converted hash on permitted params" do
+    @params.permit!
+
+    assert_instance_of Hash, @params.to_hash
+    assert_not_kind_of ActionController::Parameters, @params.to_hash
+  end
+
+  test "parameters can be implicit converted to Hash" do
+    params = ActionController::Parameters.new
+    params.permit!
 
-    assert_equal({ "controller" => "users", "action" => "create" }, params.to_h)
+    assert_equal({ a: 1 }, { a: 1 }.merge!(params))
+  end
+
+  test "to_hash returns converted hash when .permit_all_parameters is set" do
+    begin
+      ActionController::Parameters.permit_all_parameters = true
+      params = ActionController::Parameters.new(crab: "Senjougahara Hitagi")
+
+      assert_instance_of Hash, params.to_hash
+      assert_not_kind_of ActionController::Parameters, params.to_hash
+      assert_equal({ "crab" => "Senjougahara Hitagi" }, params.to_hash)
+      assert_equal({ "crab" => "Senjougahara Hitagi" }, params)
+    ensure
+      ActionController::Parameters.permit_all_parameters = false
+    end
   end
 
   test "to_unsafe_h returns unfiltered params" do
-    assert @params.to_unsafe_h.is_a? ActiveSupport::HashWithIndifferentAccess
-    assert_not @params.to_unsafe_h.is_a? ActionController::Parameters
+    assert_instance_of ActiveSupport::HashWithIndifferentAccess, @params.to_unsafe_h
+    assert_not_kind_of ActionController::Parameters, @params.to_unsafe_h
   end
 
   test "to_unsafe_h returns unfiltered params even after accessing few keys" do
-    params = ActionController::Parameters.new("f"=>{"language_facet"=>["Tibetan"]})
-    expected = {"f"=>{"language_facet"=>["Tibetan"]}}
+    params = ActionController::Parameters.new("f" => { "language_facet" => ["Tibetan"] })
+    expected = { "f" => { "language_facet" => ["Tibetan"] } }
 
-    assert params['f'].is_a? ActionController::Parameters
+    assert_instance_of ActionController::Parameters, params["f"]
     assert_equal expected, params.to_unsafe_h
   end
 
+  test "to_unsafe_h does not mutate the parameters" do
+    params = ActionController::Parameters.new("f" => { "language_facet" => ["Tibetan"] })
+    params[:f]
+
+    params.to_unsafe_h
+
+    assert_not_predicate params, :permitted?
+    assert_not_predicate params[:f], :permitted?
+  end
+
   test "to_h only deep dups Ruby collections" do
     company = Class.new do
       attr_reader :dupped
@@ -334,10 +469,10 @@ class ParametersPermitTest < ActiveSupport::TestCase
     end.new
 
     params = ActionController::Parameters.new(prem: { likes: %i( dancing ) })
-    assert_equal({ 'prem' => { 'likes' => %i( dancing ) } }, params.permit!.to_h)
+    assert_equal({ "prem" => { "likes" => %i( dancing ) } }, params.permit!.to_h)
 
     params = ActionController::Parameters.new(companies: [ company, :acme ])
-    assert_equal({ 'companies' => [ company, :acme ] }, params.permit!.to_h)
+    assert_equal({ "companies" => [ company, :acme ] }, params.permit!.to_h)
     assert_not company.dupped
   end
 
@@ -348,16 +483,16 @@ class ParametersPermitTest < ActiveSupport::TestCase
     end.new
 
     params = ActionController::Parameters.new(prem: { likes: %i( dancing ) })
-    assert_equal({ 'prem' => { 'likes' => %i( dancing ) } }, params.to_unsafe_h)
+    assert_equal({ "prem" => { "likes" => %i( dancing ) } }, params.to_unsafe_h)
 
     params = ActionController::Parameters.new(companies: [ company, :acme ])
-    assert_equal({ 'companies' => [ company, :acme ] }, params.to_unsafe_h)
+    assert_equal({ "companies" => [ company, :acme ] }, params.to_unsafe_h)
     assert_not company.dupped
   end
 
   test "include? returns true when the key is present" do
     assert @params.include? :person
-    assert @params.include? 'person'
+    assert @params.include? "person"
     assert_not @params.include? :gorilla
   end
 
@@ -369,4 +504,10 @@ class ParametersPermitTest < ActiveSupport::TestCase
     refute params.permit(foo: [:bar]).has_key?(:foo)
     refute params.permit(foo: :bar).has_key?(:foo)
   end
+
+  test "#permitted? is false by default" do
+    params = ActionController::Parameters.new
+
+    assert_equal false, params.permitted?
+  end
 end
diff --git a/actionpack/test/controller/parameters/raise_on_unpermitted_params_test.rb b/actionpack/test/controller/parameters/raise_on_unpermitted_params_test.rb
index f9cc9f96f1..4afd3da593 100644
--- a/actionpack/test/controller/parameters/raise_on_unpermitted_params_test.rb
+++ b/actionpack/test/controller/parameters/raise_on_unpermitted_params_test.rb
@@ -1,5 +1,7 @@
-require 'abstract_unit'
-require 'action_controller/metal/strong_parameters'
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "action_controller/metal/strong_parameters"
 
 class RaiseOnUnpermittedParamsTest < ActiveSupport::TestCase
   def setup
@@ -11,10 +13,9 @@ class RaiseOnUnpermittedParamsTest < ActiveSupport::TestCase
   end
 
   test "raises on unexpected params" do
-    params = ActionController::Parameters.new({
+    params = ActionController::Parameters.new(
       book: { pages: 65 },
-      fishing: "Turnips"
-    })
+      fishing: "Turnips")
 
     assert_raises(ActionController::UnpermittedParameters) do
       params.permit(book: [:pages])
@@ -22,9 +23,8 @@ class RaiseOnUnpermittedParamsTest < ActiveSupport::TestCase
   end
 
   test "raises on unexpected nested params" do
-    params = ActionController::Parameters.new({
-      book: { pages: 65, title: "Green Cats and where to find then." }
-    })
+    params = ActionController::Parameters.new(
+      book: { pages: 65, title: "Green Cats and where to find then." })
 
     assert_raises(ActionController::UnpermittedParameters) do
       params.permit(book: [:pages])
diff --git a/actionpack/test/controller/parameters/serialization_test.rb b/actionpack/test/controller/parameters/serialization_test.rb
new file mode 100644
index 0000000000..823f01d82a
--- /dev/null
+++ b/actionpack/test/controller/parameters/serialization_test.rb
@@ -0,0 +1,55 @@
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "action_controller/metal/strong_parameters"
+require "active_support/core_ext/string/strip"
+
+class ParametersSerializationTest < ActiveSupport::TestCase
+  setup do
+    @old_permitted_parameters = ActionController::Parameters.permit_all_parameters
+    ActionController::Parameters.permit_all_parameters = false
+  end
+
+  teardown do
+    ActionController::Parameters.permit_all_parameters = @old_permitted_parameters
+  end
+
+  test "yaml serialization" do
+    params = ActionController::Parameters.new(key: :value)
+    yaml_dump = YAML.dump(params)
+    assert_match("--- !ruby/object:ActionController::Parameters", yaml_dump)
+    assert_match(/parameters: !ruby\/hash:ActiveSupport::HashWithIndifferentAccess\n\s+key: :value/, yaml_dump)
+    assert_match("permitted: false", yaml_dump)
+  end
+
+  test "yaml deserialization" do
+    params = ActionController::Parameters.new(key: :value)
+    roundtripped = YAML.load(YAML.dump(params))
+
+    assert_equal params, roundtripped
+    assert_not roundtripped.permitted?
+  end
+
+  test "yaml backwardscompatible with psych 2.0.8 format" do
+    params = YAML.load <<-end_of_yaml.strip_heredoc
+      --- !ruby/hash:ActionController::Parameters
+      key: :value
+    end_of_yaml
+
+    assert_equal :value, params[:key]
+    assert_not params.permitted?
+  end
+
+  test "yaml backwardscompatible with psych 2.0.9+ format" do
+    params = YAML.load(<<-end_of_yaml.strip_heredoc)
+      --- !ruby/hash-with-ivars:ActionController::Parameters
+      elements:
+        key: :value
+      ivars:
+        :@permitted: false
+    end_of_yaml
+
+    assert_equal :value, params[:key]
+    assert_not params.permitted?
+  end
+end
diff --git a/actionpack/test/controller/params_wrapper_test.rb b/actionpack/test/controller/params_wrapper_test.rb
index 7226beed26..c4c74e8f2b 100644
--- a/actionpack/test/controller/params_wrapper_test.rb
+++ b/actionpack/test/controller/params_wrapper_test.rb
@@ -1,10 +1,12 @@
-require 'abstract_unit'
+# frozen_string_literal: true
+
+require "abstract_unit"
 
 module Admin; class User; end; end
 
 module ParamsWrapperTestHelp
   def with_default_wrapper_options(&block)
-    @controller.class._set_wrapper_options({:format => [:json]})
+    @controller.class._set_wrapper_options(format: [:json])
     @controller.class.inherited(@controller.class)
     yield
   end
@@ -32,6 +34,10 @@ class ParamsWrapperTest < ActionController::TestCase
     def self.attribute_names
       []
     end
+
+    def self.stored_attributes
+      { settings: [:color, :size] }
+    end
   end
 
   class Person
@@ -48,17 +54,28 @@ class ParamsWrapperTest < ActionController::TestCase
 
   def test_filtered_parameters
     with_default_wrapper_options do
-      @request.env['CONTENT_TYPE'] = 'application/json'
-      post :parse, params: { 'username' => 'sikachu' }
-      assert_equal @request.filtered_parameters, { 'controller' => 'params_wrapper_test/users', 'action' => 'parse', 'username' => 'sikachu', 'user' => { 'username' => 'sikachu' } }
+      @request.env["CONTENT_TYPE"] = "application/json"
+      post :parse, params: { "username" => "sikachu" }
+      assert_equal({ "controller" => "params_wrapper_test/users", "action" => "parse", "username" => "sikachu", "user" => { "username" => "sikachu" } }, @request.filtered_parameters)
     end
   end
 
   def test_derived_name_from_controller
     with_default_wrapper_options do
-      @request.env['CONTENT_TYPE'] = 'application/json'
-      post :parse, params: { 'username' => 'sikachu' }
-      assert_parameters({ 'username' => 'sikachu', 'user' => { 'username' => 'sikachu' }})
+      @request.env["CONTENT_TYPE"] = "application/json"
+      post :parse, params: { "username" => "sikachu" }
+      assert_parameters("username" => "sikachu", "user" => { "username" => "sikachu" })
+    end
+  end
+
+  def test_store_accessors_wrapped
+    assert_called(User, :attribute_names, times: 2, returns: ["username"]) do
+      with_default_wrapper_options do
+        @request.env["CONTENT_TYPE"] = "application/json"
+        post :parse, params: { "username" => "sikachu", "color" => "blue", "size" => "large" }
+        assert_parameters("username" => "sikachu", "color" => "blue", "size" => "large",
+                           "user" => { "username" => "sikachu", "color" => "blue", "size" => "large" })
+      end
     end
   end
 
@@ -66,9 +83,9 @@ class ParamsWrapperTest < ActionController::TestCase
     with_default_wrapper_options do
       UsersController.wrap_parameters :person
 
-      @request.env['CONTENT_TYPE'] = 'application/json'
-      post :parse, params: { 'username' => 'sikachu' }
-      assert_parameters({ 'username' => 'sikachu', 'person' => { 'username' => 'sikachu' }})
+      @request.env["CONTENT_TYPE"] = "application/json"
+      post :parse, params: { "username" => "sikachu" }
+      assert_parameters("username" => "sikachu", "person" => { "username" => "sikachu" })
     end
   end
 
@@ -76,99 +93,107 @@ class ParamsWrapperTest < ActionController::TestCase
     with_default_wrapper_options do
       UsersController.wrap_parameters Person
 
-      @request.env['CONTENT_TYPE'] = 'application/json'
-      post :parse, params: { 'username' => 'sikachu' }
-      assert_parameters({ 'username' => 'sikachu', 'person' => { 'username' => 'sikachu' }})
+      @request.env["CONTENT_TYPE"] = "application/json"
+      post :parse, params: { "username" => "sikachu" }
+      assert_parameters("username" => "sikachu", "person" => { "username" => "sikachu" })
     end
   end
 
   def test_specify_include_option
     with_default_wrapper_options do
-      UsersController.wrap_parameters :include => :username
+      UsersController.wrap_parameters include: :username
 
-      @request.env['CONTENT_TYPE'] = 'application/json'
-      post :parse, params: { 'username' => 'sikachu', 'title' => 'Developer' }
-      assert_parameters({ 'username' => 'sikachu', 'title' => 'Developer', 'user' => { 'username' => 'sikachu' }})
+      @request.env["CONTENT_TYPE"] = "application/json"
+      post :parse, params: { "username" => "sikachu", "title" => "Developer" }
+      assert_parameters("username" => "sikachu", "title" => "Developer", "user" => { "username" => "sikachu" })
     end
   end
 
   def test_specify_exclude_option
     with_default_wrapper_options do
-      UsersController.wrap_parameters :exclude => :title
+      UsersController.wrap_parameters exclude: :title
 
-      @request.env['CONTENT_TYPE'] = 'application/json'
-      post :parse, params: { 'username' => 'sikachu', 'title' => 'Developer' }
-      assert_parameters({ 'username' => 'sikachu', 'title' => 'Developer', 'user' => { 'username' => 'sikachu' }})
+      @request.env["CONTENT_TYPE"] = "application/json"
+      post :parse, params: { "username" => "sikachu", "title" => "Developer" }
+      assert_parameters("username" => "sikachu", "title" => "Developer", "user" => { "username" => "sikachu" })
     end
   end
 
   def test_specify_both_wrapper_name_and_include_option
     with_default_wrapper_options do
-      UsersController.wrap_parameters :person, :include => :username
+      UsersController.wrap_parameters :person, include: :username
 
-      @request.env['CONTENT_TYPE'] = 'application/json'
-      post :parse, params: { 'username' => 'sikachu', 'title' => 'Developer' }
-      assert_parameters({ 'username' => 'sikachu', 'title' => 'Developer', 'person' => { 'username' => 'sikachu' }})
+      @request.env["CONTENT_TYPE"] = "application/json"
+      post :parse, params: { "username" => "sikachu", "title" => "Developer" }
+      assert_parameters("username" => "sikachu", "title" => "Developer", "person" => { "username" => "sikachu" })
     end
   end
 
   def test_not_enabled_format
     with_default_wrapper_options do
-      @request.env['CONTENT_TYPE'] = 'application/xml'
-      post :parse, params: { 'username' => 'sikachu', 'title' => 'Developer' }
-      assert_parameters({ 'username' => 'sikachu', 'title' => 'Developer' })
+      @request.env["CONTENT_TYPE"] = "application/xml"
+      post :parse, params: { "username" => "sikachu", "title" => "Developer" }
+      assert_parameters("username" => "sikachu", "title" => "Developer")
     end
   end
 
   def test_wrap_parameters_false
     with_default_wrapper_options do
       UsersController.wrap_parameters false
-      @request.env['CONTENT_TYPE'] = 'application/json'
-      post :parse, params: { 'username' => 'sikachu', 'title' => 'Developer' }
-      assert_parameters({ 'username' => 'sikachu', 'title' => 'Developer' })
+      @request.env["CONTENT_TYPE"] = "application/json"
+      post :parse, params: { "username" => "sikachu", "title" => "Developer" }
+      assert_parameters("username" => "sikachu", "title" => "Developer")
     end
   end
 
   def test_specify_format
     with_default_wrapper_options do
-      UsersController.wrap_parameters :format => :xml
+      UsersController.wrap_parameters format: :xml
 
-      @request.env['CONTENT_TYPE'] = 'application/xml'
-      post :parse, params: { 'username' => 'sikachu', 'title' => 'Developer' }
-      assert_parameters({ 'username' => 'sikachu', 'title' => 'Developer', 'user' => { 'username' => 'sikachu', 'title' => 'Developer' }})
+      @request.env["CONTENT_TYPE"] = "application/xml"
+      post :parse, params: { "username" => "sikachu", "title" => "Developer" }
+      assert_parameters("username" => "sikachu", "title" => "Developer", "user" => { "username" => "sikachu", "title" => "Developer" })
     end
   end
 
   def test_not_wrap_reserved_parameters
     with_default_wrapper_options do
-      @request.env['CONTENT_TYPE'] = 'application/json'
-      post :parse, params: { 'authenticity_token' => 'pwned', '_method' => 'put', 'utf8' => '&#9731;', 'username' => 'sikachu' }
-      assert_parameters({ 'authenticity_token' => 'pwned', '_method' => 'put', 'utf8' => '&#9731;', 'username' => 'sikachu', 'user' => { 'username' => 'sikachu' }})
+      @request.env["CONTENT_TYPE"] = "application/json"
+      post :parse, params: { "authenticity_token" => "pwned", "_method" => "put", "utf8" => "&#9731;", "username" => "sikachu" }
+      assert_parameters("authenticity_token" => "pwned", "_method" => "put", "utf8" => "&#9731;", "username" => "sikachu", "user" => { "username" => "sikachu" })
     end
   end
 
   def test_no_double_wrap_if_key_exists
     with_default_wrapper_options do
-      @request.env['CONTENT_TYPE'] = 'application/json'
-      post :parse, params: { 'user' => { 'username' => 'sikachu' }}
-      assert_parameters({ 'user' => { 'username' => 'sikachu' }})
+      @request.env["CONTENT_TYPE"] = "application/json"
+      post :parse, params: { "user" => { "username" => "sikachu" } }
+      assert_parameters("user" => { "username" => "sikachu" })
+    end
+  end
+
+  def test_no_double_wrap_if_key_exists_and_value_is_nil
+    with_default_wrapper_options do
+      @request.env["CONTENT_TYPE"] = "application/json"
+      post :parse, params: { "user" => nil }
+      assert_parameters("user" => nil)
     end
   end
 
   def test_nested_params
     with_default_wrapper_options do
-      @request.env['CONTENT_TYPE'] = 'application/json'
-      post :parse, params: { 'person' => { 'username' => 'sikachu' }}
-      assert_parameters({ 'person' => { 'username' => 'sikachu' }, 'user' => {'person' => { 'username' => 'sikachu' }}})
+      @request.env["CONTENT_TYPE"] = "application/json"
+      post :parse, params: { "person" => { "username" => "sikachu" } }
+      assert_parameters("person" => { "username" => "sikachu" }, "user" => { "person" => { "username" => "sikachu" } })
     end
   end
 
   def test_derived_wrapped_keys_from_matching_model
     assert_called(User, :attribute_names, times: 2, returns: ["username"]) do
       with_default_wrapper_options do
-        @request.env['CONTENT_TYPE'] = 'application/json'
-        post :parse, params: { 'username' => 'sikachu', 'title' => 'Developer' }
-        assert_parameters({ 'username' => 'sikachu', 'title' => 'Developer', 'user' => { 'username' => 'sikachu' }})
+        @request.env["CONTENT_TYPE"] = "application/json"
+        post :parse, params: { "username" => "sikachu", "title" => "Developer" }
+        assert_parameters("username" => "sikachu", "title" => "Developer", "user" => { "username" => "sikachu" })
       end
     end
   end
@@ -178,40 +203,72 @@ class ParamsWrapperTest < ActionController::TestCase
       assert_called(Person, :attribute_names, times: 2, returns: ["username"]) do
         UsersController.wrap_parameters Person
 
-        @request.env['CONTENT_TYPE'] = 'application/json'
-        post :parse, params: { 'username' => 'sikachu', 'title' => 'Developer' }
-        assert_parameters({ 'username' => 'sikachu', 'title' => 'Developer', 'person' => { 'username' => 'sikachu' }})
+        @request.env["CONTENT_TYPE"] = "application/json"
+        post :parse, params: { "username" => "sikachu", "title" => "Developer" }
+        assert_parameters("username" => "sikachu", "title" => "Developer", "person" => { "username" => "sikachu" })
       end
     end
   end
 
   def test_not_wrapping_abstract_model
     with_default_wrapper_options do
-      @request.env['CONTENT_TYPE'] = 'application/json'
-      post :parse, params: { 'username' => 'sikachu', 'title' => 'Developer' }
-      assert_parameters({ 'username' => 'sikachu', 'title' => 'Developer', 'user' => { 'username' => 'sikachu', 'title' => 'Developer' }})
+      @request.env["CONTENT_TYPE"] = "application/json"
+      post :parse, params: { "username" => "sikachu", "title" => "Developer" }
+      assert_parameters("username" => "sikachu", "title" => "Developer", "user" => { "username" => "sikachu", "title" => "Developer" })
     end
   end
 
   def test_preserves_query_string_params
     with_default_wrapper_options do
-      @request.env['CONTENT_TYPE'] = 'application/json'
-      get :parse, params: { 'user' => { 'username' => 'nixon' } }
+      @request.env["CONTENT_TYPE"] = "application/json"
+      get :parse, params: { "user" => { "username" => "nixon" } }
       assert_parameters(
-        {'user' => { 'username' => 'nixon' } }
+        "user" => { "username" => "nixon" }
       )
     end
   end
 
+  def test_preserves_query_string_params_in_filtered_params
+    with_default_wrapper_options do
+      @request.env["CONTENT_TYPE"] = "application/json"
+      get :parse, params: { "user" => { "username" => "nixon" } }
+      assert_equal({ "controller" => "params_wrapper_test/users", "action" => "parse", "user" => { "username" => "nixon" } }, @request.filtered_parameters)
+    end
+  end
+
   def test_empty_parameter_set
     with_default_wrapper_options do
-      @request.env['CONTENT_TYPE'] = 'application/json'
+      @request.env["CONTENT_TYPE"] = "application/json"
       post :parse, params: {}
       assert_parameters(
-        {'user' => { } }
+        "user" => {}
       )
     end
   end
+
+  def test_handles_empty_content_type
+    with_default_wrapper_options do
+      @request.env["CONTENT_TYPE"] = nil
+      _controller_class.dispatch(:parse, @request, @response)
+
+      assert_equal 200, @response.status
+      assert_equal "", @response.body
+    end
+  end
+
+  def test_derived_wrapped_keys_from_nested_attributes
+    def User.nested_attributes_options
+      { person: {} }
+    end
+
+    assert_called(User, :attribute_names, times: 2, returns: ["username"]) do
+      with_default_wrapper_options do
+        @request.env["CONTENT_TYPE"] = "application/json"
+        post :parse, params: { "username" => "sikachu", "person_attributes" => { "title" => "Developer" } }
+        assert_parameters("username" => "sikachu", "person_attributes" => { "title" => "Developer" }, "user" => { "username" => "sikachu", "person_attributes" => { "title" => "Developer" } })
+      end
+    end
+  end
 end
 
 class NamespacedParamsWrapperTest < ActionController::TestCase
@@ -219,7 +276,7 @@ class NamespacedParamsWrapperTest < ActionController::TestCase
 
   module Admin
     module Users
-      class UsersController < ActionController::Base;
+      class UsersController < ActionController::Base
         class << self
           attr_accessor :last_parameters
         end
@@ -252,9 +309,9 @@ class NamespacedParamsWrapperTest < ActionController::TestCase
 
   def test_derived_name_from_controller
     with_default_wrapper_options do
-      @request.env['CONTENT_TYPE'] = 'application/json'
-      post :parse, params: { 'username' => 'sikachu' }
-      assert_parameters({'username' => 'sikachu', 'user' => { 'username' => 'sikachu' }})
+      @request.env["CONTENT_TYPE"] = "application/json"
+      post :parse, params: { "username" => "sikachu" }
+      assert_parameters("username" => "sikachu", "user" => { "username" => "sikachu" })
     end
   end
 
@@ -262,9 +319,9 @@ class NamespacedParamsWrapperTest < ActionController::TestCase
     Admin.const_set(:User, Class.new(SampleOne))
     begin
       with_default_wrapper_options do
-        @request.env['CONTENT_TYPE'] = 'application/json'
-        post :parse, params: { 'username' => 'sikachu', 'title' => 'Developer' }
-        assert_parameters({ 'username' => 'sikachu', 'title' => 'Developer', 'user' => { 'username' => 'sikachu' }})
+        @request.env["CONTENT_TYPE"] = "application/json"
+        post :parse, params: { "username" => "sikachu", "title" => "Developer" }
+        assert_parameters("username" => "sikachu", "title" => "Developer", "user" => { "username" => "sikachu" })
       end
     ensure
       Admin.send :remove_const, :User
@@ -275,15 +332,14 @@ class NamespacedParamsWrapperTest < ActionController::TestCase
     Object.const_set(:User, Class.new(SampleTwo))
     begin
       with_default_wrapper_options do
-        @request.env['CONTENT_TYPE'] = 'application/json'
-        post :parse, params: { 'username' => 'sikachu', 'title' => 'Developer' }
-        assert_parameters({ 'username' => 'sikachu', 'title' => 'Developer', 'user' => { 'title' => 'Developer' }})
+        @request.env["CONTENT_TYPE"] = "application/json"
+        post :parse, params: { "username" => "sikachu", "title" => "Developer" }
+        assert_parameters("username" => "sikachu", "title" => "Developer", "user" => { "title" => "Developer" })
       end
     ensure
       Object.send :remove_const, :User
     end
   end
-
 end
 
 class AnonymousControllerParamsWrapperTest < ActionController::TestCase
@@ -302,18 +358,18 @@ class AnonymousControllerParamsWrapperTest < ActionController::TestCase
 
   def test_does_not_implicitly_wrap_params
     with_default_wrapper_options do
-      @request.env['CONTENT_TYPE'] = 'application/json'
-      post :parse, params: { 'username' => 'sikachu' }
-      assert_parameters({ 'username' => 'sikachu' })
+      @request.env["CONTENT_TYPE"] = "application/json"
+      post :parse, params: { "username" => "sikachu" }
+      assert_parameters("username" => "sikachu")
     end
   end
 
   def test_does_wrap_params_if_name_provided
     with_default_wrapper_options do
-      @controller.class.wrap_parameters(:name => "guest")
-      @request.env['CONTENT_TYPE'] = 'application/json'
-      post :parse, params: { 'username' => 'sikachu' }
-      assert_parameters({ 'username' => 'sikachu', 'guest' => { 'username' => 'sikachu' }})
+      @controller.class.wrap_parameters(name: "guest")
+      @request.env["CONTENT_TYPE"] = "application/json"
+      post :parse, params: { "username" => "sikachu" }
+      assert_parameters("username" => "sikachu", "guest" => { "username" => "sikachu" })
     end
   end
 end
@@ -323,7 +379,7 @@ class IrregularInflectionParamsWrapperTest < ActionController::TestCase
 
   class ParamswrappernewsItem
     def self.attribute_names
-      ['test_attr']
+      ["test_attr"]
     end
   end
 
@@ -343,24 +399,24 @@ class IrregularInflectionParamsWrapperTest < ActionController::TestCase
   def test_uses_model_attribute_names_with_irregular_inflection
     with_dup do
       ActiveSupport::Inflector.inflections do |inflect|
-        inflect.irregular 'paramswrappernews_item', 'paramswrappernews'
+        inflect.irregular "paramswrappernews_item", "paramswrappernews"
       end
 
       with_default_wrapper_options do
-        @request.env['CONTENT_TYPE'] = 'application/json'
-        post :parse, params: { 'username' => 'sikachu', 'test_attr' => 'test_value' }
-        assert_parameters({ 'username' => 'sikachu', 'test_attr' => 'test_value', 'paramswrappernews_item' => { 'test_attr' => 'test_value' }})
+        @request.env["CONTENT_TYPE"] = "application/json"
+        post :parse, params: { "username" => "sikachu", "test_attr" => "test_value" }
+        assert_parameters("username" => "sikachu", "test_attr" => "test_value", "paramswrappernews_item" => { "test_attr" => "test_value" })
       end
     end
   end
 
   private
 
-  def with_dup
-    original = ActiveSupport::Inflector::Inflections.instance_variable_get(:@__instance__)[:en]
-    ActiveSupport::Inflector::Inflections.instance_variable_set(:@__instance__, en: original.dup)
-    yield
-  ensure
-    ActiveSupport::Inflector::Inflections.instance_variable_set(:@__instance__, en: original)
-  end
+    def with_dup
+      original = ActiveSupport::Inflector::Inflections.instance_variable_get(:@__instance__)[:en]
+      ActiveSupport::Inflector::Inflections.instance_variable_set(:@__instance__, en: original.dup)
+      yield
+    ensure
+      ActiveSupport::Inflector::Inflections.instance_variable_set(:@__instance__, en: original)
+    end
 end
diff --git a/actionpack/test/controller/permitted_params_test.rb b/actionpack/test/controller/permitted_params_test.rb
index 7c753a45a5..caac88ffb2 100644
--- a/actionpack/test/controller/permitted_params_test.rb
+++ b/actionpack/test/controller/permitted_params_test.rb
@@ -1,4 +1,6 @@
-require 'abstract_unit'
+# frozen_string_literal: true
+
+require "abstract_unit"
 
 class PeopleController < ActionController::Base
   def create
diff --git a/actionpack/test/controller/redirect_test.rb b/actionpack/test/controller/redirect_test.rb
index 4af3c628d0..2959dc3e4d 100644
--- a/actionpack/test/controller/redirect_test.rb
+++ b/actionpack/test/controller/redirect_test.rb
@@ -1,4 +1,6 @@
-require 'abstract_unit'
+# frozen_string_literal: true
+
+require "abstract_unit"
 
 class Workshop
   extend ActiveModel::Naming
@@ -21,55 +23,55 @@ end
 class RedirectController < ActionController::Base
   # empty method not used anywhere to ensure methods like
   # `status` and `location` aren't called on `redirect_to` calls
-  def status; render plain: 'called status'; end
-  def location; render plain: 'called location'; end
+  def status; raise "Should not be called!"; end
+  def location; raise "Should not be called!"; end
 
   def simple_redirect
-    redirect_to :action => "hello_world"
+    redirect_to action: "hello_world"
   end
 
   def redirect_with_status
-    redirect_to({:action => "hello_world", :status => 301})
+    redirect_to(action: "hello_world", status: 301)
   end
 
   def redirect_with_status_hash
-    redirect_to({:action => "hello_world"}, {:status => 301})
+    redirect_to({ action: "hello_world" }, { status: 301 })
   end
 
   def redirect_with_protocol
-    redirect_to :action => "hello_world", :protocol => "https"
+    redirect_to action: "hello_world", protocol: "https"
   end
 
   def url_redirect_with_status
-    redirect_to("http://www.example.com", :status => :moved_permanently)
+    redirect_to("http://www.example.com", status: :moved_permanently)
   end
 
   def url_redirect_with_status_hash
-    redirect_to("http://www.example.com", {:status => 301})
+    redirect_to("http://www.example.com", status: 301)
   end
 
   def relative_url_redirect_with_status
-    redirect_to("/things/stuff", :status => :found)
+    redirect_to("/things/stuff", status: :found)
   end
 
   def relative_url_redirect_with_status_hash
-    redirect_to("/things/stuff", {:status => 301})
-  end
-
-  def redirect_to_back_with_status
-    redirect_to :back, :status => 307
+    redirect_to("/things/stuff", status: 301)
   end
 
   def redirect_back_with_status
     redirect_back(fallback_location: "/things/stuff", status: 307)
   end
 
+  def safe_redirect_back_with_status
+    redirect_back(fallback_location: "/things/stuff", status: 307, allow_other_host: false)
+  end
+
   def host_redirect
-    redirect_to :action => "other_host", :only_path => false, :host => 'other.test.host'
+    redirect_to action: "other_host", only_path: false, host: "other.test.host"
   end
 
   def module_redirect
-    redirect_to :controller => 'module_test/module_redirect', :action => "hello_world"
+    redirect_to controller: "module_test/module_redirect", action: "hello_world"
   end
 
   def redirect_to_url
@@ -88,10 +90,6 @@ class RedirectController < ActionController::Base
     redirect_to "//www.rubyonrails.org/"
   end
 
-  def redirect_to_back
-    redirect_to :back
-  end
-
   def redirect_to_existing_record
     redirect_to Workshop.new(5)
   end
@@ -105,7 +103,7 @@ class RedirectController < ActionController::Base
   end
 
   def redirect_to_params
-    redirect_to ActionController::Parameters.new(status: 200, protocol: 'javascript', f: '%0Aeval(name)')
+    redirect_to ActionController::Parameters.new(status: 200, protocol: "javascript", f: "%0Aeval(name)")
   end
 
   def redirect_to_with_block
@@ -118,7 +116,7 @@ class RedirectController < ActionController::Base
   end
 
   def redirect_to_with_block_and_options
-    redirect_to proc { {:action => "hello_world"} }
+    redirect_to proc { { action: "hello_world" } }
   end
 
   def redirect_with_header_break
@@ -131,9 +129,9 @@ class RedirectController < ActionController::Base
 
   def rescue_errors(e) raise e end
 
-  protected
+  private
     def dashbord_url(id, message)
-      url_for :action => "dashboard", :params => { "id" => id, "message" => message }
+      url_for action: "dashboard", params: { "id" => id, "message" => message }
     end
 end
 
@@ -206,21 +204,10 @@ class RedirectTest < ActionController::TestCase
     assert_equal "http://test.host/things/stuff", redirect_to_url
   end
 
-  def test_redirect_to_back_with_status
-    @request.env["HTTP_REFERER"] = "http://www.example.com/coming/from"
-
-    assert_deprecated do
-      get :redirect_to_back_with_status
-    end
-
-    assert_response 307
-    assert_equal "http://www.example.com/coming/from", redirect_to_url
-  end
-
   def test_simple_redirect_using_options
     get :host_redirect
     assert_response :redirect
-    assert_redirected_to :action => "other_host", :only_path => false, :host => 'other.test.host'
+    assert_redirected_to action: "other_host", only_path: false, host: "other.test.host"
   end
 
   def test_module_redirect
@@ -232,7 +219,7 @@ class RedirectTest < ActionController::TestCase
   def test_module_redirect_using_options
     get :module_redirect
     assert_response :redirect
-    assert_redirected_to :controller => 'module_test/module_redirect', :action => 'hello_world'
+    assert_redirected_to controller: "module_test/module_redirect", action: "hello_world"
   end
 
   def test_redirect_to_url
@@ -259,29 +246,6 @@ class RedirectTest < ActionController::TestCase
     assert_equal "//www.rubyonrails.org/", redirect_to_url
   end
 
-  def test_redirect_to_back
-    @request.env["HTTP_REFERER"] = "http://www.example.com/coming/from"
-
-    assert_deprecated do
-      get :redirect_to_back
-    end
-
-    assert_response :redirect
-    assert_equal "http://www.example.com/coming/from", redirect_to_url
-  end
-
-  def test_redirect_to_back_with_no_referer
-    assert_raise(ActionController::RedirectBackError) {
-      @request.env["HTTP_REFERER"] = nil
-
-      assert_deprecated do
-        get :redirect_to_back
-      end
-
-      get :redirect_to_back
-    }
-  end
-
   def test_redirect_back
     referer = "http://www.example.com/coming/from"
     @request.env["HTTP_REFERER"] = referer
@@ -299,13 +263,30 @@ class RedirectTest < ActionController::TestCase
     assert_equal "http://test.host/things/stuff", redirect_to_url
   end
 
+  def test_safe_redirect_back_from_other_host
+    @request.env["HTTP_REFERER"] = "http://another.host/coming/from"
+    get :safe_redirect_back_with_status
+
+    assert_response 307
+    assert_equal "http://test.host/things/stuff", redirect_to_url
+  end
+
+  def test_safe_redirect_back_from_the_same_host
+    referer = "http://test.host/coming/from"
+    @request.env["HTTP_REFERER"] = referer
+    get :safe_redirect_back_with_status
+
+    assert_response 307
+    assert_equal referer, redirect_to_url
+  end
+
   def test_redirect_to_record
     with_routing do |set|
       set.draw do
         resources :workshops
 
         ActiveSupport::Deprecation.silence do
-          get ':controller/:action'
+          get ":controller/:action"
         end
       end
 
@@ -327,10 +308,10 @@ class RedirectTest < ActionController::TestCase
   end
 
   def test_redirect_to_params
-    error = assert_raise(ArgumentError) do
+    error = assert_raise(ActionController::UnfilteredParameters) do
       get :redirect_to_params
     end
-    assert_equal ActionDispatch::Routing::INSECURE_URL_PARAMETERS_MESSAGE, error.message
+    assert_equal "unable to convert unpermitted parameters to hash", error.message
   end
 
   def test_redirect_to_with_block
@@ -349,7 +330,7 @@ class RedirectTest < ActionController::TestCase
     with_routing do |set|
       set.draw do
         ActiveSupport::Deprecation.silence do
-          get ':controller/:action'
+          get ":controller/:action"
         end
       end
 
@@ -364,7 +345,7 @@ end
 module ModuleTest
   class ModuleRedirectController < ::RedirectController
     def module_redirect
-      redirect_to :controller => '/redirect', :action => "hello_world"
+      redirect_to controller: "/redirect", action: "hello_world"
     end
   end
 
@@ -380,7 +361,7 @@ module ModuleTest
     def test_simple_redirect_using_options
       get :host_redirect
       assert_response :redirect
-      assert_redirected_to :action => "other_host", :only_path => false, :host => 'other.test.host'
+      assert_redirected_to action: "other_host", only_path: false, host: "other.test.host"
     end
 
     def test_module_redirect
@@ -392,7 +373,7 @@ module ModuleTest
     def test_module_redirect_using_options
       get :module_redirect
       assert_response :redirect
-      assert_redirected_to :controller => '/redirect', :action => "hello_world"
+      assert_redirected_to controller: "/redirect", action: "hello_world"
     end
   end
 end
diff --git a/actionpack/test/controller/render_js_test.rb b/actionpack/test/controller/render_js_test.rb
index 6b661de064..1efc0b9de1 100644
--- a/actionpack/test/controller/render_js_test.rb
+++ b/actionpack/test/controller/render_js_test.rb
@@ -1,21 +1,23 @@
-require 'abstract_unit'
-require 'controller/fake_models'
-require 'pathname'
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "controller/fake_models"
+require "pathname"
 
 class RenderJSTest < ActionController::TestCase
   class TestController < ActionController::Base
     protect_from_forgery
 
     def self.controller_path
-      'test'
+      "test"
     end
 
     def render_vanilla_js_hello
-      render :js => "alert('hello')"
+      render js: "alert('hello')"
     end
 
     def show_partial
-      render :partial => 'partial'
+      render partial: "partial"
     end
   end
 
@@ -28,7 +30,7 @@ class RenderJSTest < ActionController::TestCase
   end
 
   def test_should_render_js_partial
-    get :show_partial, format: 'js', xhr: true
-    assert_equal 'partial js', @response.body
+    get :show_partial, format: "js", xhr: true
+    assert_equal "partial js", @response.body
   end
 end
diff --git a/actionpack/test/controller/render_json_test.rb b/actionpack/test/controller/render_json_test.rb
index 3773900cc4..82c1ba26cb 100644
--- a/actionpack/test/controller/render_json_test.rb
+++ b/actionpack/test/controller/render_json_test.rb
@@ -1,18 +1,20 @@
-require 'abstract_unit'
-require 'controller/fake_models'
-require 'active_support/logger'
-require 'pathname'
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "controller/fake_models"
+require "active_support/logger"
+require "pathname"
 
 class RenderJsonTest < ActionController::TestCase
   class JsonRenderable
-    def as_json(options={})
-      hash = { :a => :b, :c => :d, :e => :f }
+    def as_json(options = {})
+      hash = { a: :b, c: :d, e: :f }
       hash.except!(*options[:except]) if options[:except]
       hash
     end
 
     def to_json(options = {})
-      super :except => [:c, :e]
+      super except: [:c, :e]
     end
   end
 
@@ -20,47 +22,47 @@ class RenderJsonTest < ActionController::TestCase
     protect_from_forgery
 
     def self.controller_path
-      'test'
+      "test"
     end
 
     def render_json_nil
-      render :json => nil
+      render json: nil
     end
 
     def render_json_render_to_string
-      render plain: render_to_string(json: '[]')
+      render plain: render_to_string(json: "[]")
     end
 
     def render_json_hello_world
-      render :json => ActiveSupport::JSON.encode(:hello => 'world')
+      render json: ActiveSupport::JSON.encode(hello: "world")
     end
 
     def render_json_hello_world_with_status
-      render :json => ActiveSupport::JSON.encode(:hello => 'world'), :status => 401
+      render json: ActiveSupport::JSON.encode(hello: "world"), status: 401
     end
 
     def render_json_hello_world_with_callback
-      render :json => ActiveSupport::JSON.encode(:hello => 'world'), :callback => 'alert'
+      render json: ActiveSupport::JSON.encode(hello: "world"), callback: "alert"
     end
 
     def render_json_with_custom_content_type
-      render :json => ActiveSupport::JSON.encode(:hello => 'world'), :content_type => 'text/javascript'
+      render json: ActiveSupport::JSON.encode(hello: "world"), content_type: "text/javascript"
     end
 
     def render_symbol_json
-      render :json => ActiveSupport::JSON.encode(:hello => 'world')
+      render json: ActiveSupport::JSON.encode(hello: "world")
     end
 
     def render_json_with_render_to_string
-      render :json => {:hello => render_to_string(:partial => 'partial')}
+      render json: { hello: render_to_string(partial: "partial") }
     end
 
     def render_json_with_extra_options
-      render :json => JsonRenderable.new, :except => [:c, :e]
+      render json: JsonRenderable.new, except: [:c, :e]
     end
 
     def render_json_without_options
-      render :json => JsonRenderable.new
+      render json: JsonRenderable.new
     end
   end
 
@@ -77,20 +79,19 @@ class RenderJsonTest < ActionController::TestCase
 
   def test_render_json_nil
     get :render_json_nil
-    assert_equal 'null', @response.body
-    assert_equal 'application/json', @response.content_type
+    assert_equal "null", @response.body
+    assert_equal "application/json", @response.content_type
   end
 
   def test_render_json_render_to_string
     get :render_json_render_to_string
-    assert_equal '[]', @response.body
+    assert_equal "[]", @response.body
   end
 
-
   def test_render_json
     get :render_json_hello_world
     assert_equal '{"hello":"world"}', @response.body
-    assert_equal 'application/json', @response.content_type
+    assert_equal "application/json", @response.content_type
   end
 
   def test_render_json_with_status
@@ -102,31 +103,31 @@ class RenderJsonTest < ActionController::TestCase
   def test_render_json_with_callback
     get :render_json_hello_world_with_callback, xhr: true
     assert_equal '/**/alert({"hello":"world"})', @response.body
-    assert_equal 'text/javascript', @response.content_type
+    assert_equal "text/javascript", @response.content_type
   end
 
   def test_render_json_with_custom_content_type
     get :render_json_with_custom_content_type, xhr: true
     assert_equal '{"hello":"world"}', @response.body
-    assert_equal 'text/javascript', @response.content_type
+    assert_equal "text/javascript", @response.content_type
   end
 
   def test_render_symbol_json
     get :render_symbol_json
     assert_equal '{"hello":"world"}', @response.body
-    assert_equal 'application/json', @response.content_type
+    assert_equal "application/json", @response.content_type
   end
 
   def test_render_json_with_render_to_string
     get :render_json_with_render_to_string
     assert_equal '{"hello":"partial html"}', @response.body
-    assert_equal 'application/json', @response.content_type
+    assert_equal "application/json", @response.content_type
   end
 
   def test_render_json_forwards_extra_options
     get :render_json_with_extra_options
     assert_equal '{"a":"b"}', @response.body
-    assert_equal 'application/json', @response.content_type
+    assert_equal "application/json", @response.content_type
   end
 
   def test_render_json_calls_to_json_from_object
diff --git a/actionpack/test/controller/render_test.rb b/actionpack/test/controller/render_test.rb
index 8d3134630d..7c5101f993 100644
--- a/actionpack/test/controller/render_test.rb
+++ b/actionpack/test/controller/render_test.rb
@@ -1,15 +1,20 @@
-require 'abstract_unit'
-require 'controller/fake_models'
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "controller/fake_models"
 
 class TestControllerWithExtraEtags < ActionController::Base
+  def self.controller_name; "test"; end
+  def self.controller_path; "test"; end
+
   etag { nil  }
-  etag { 'ab' }
+  etag { "ab" }
   etag { :cde }
   etag { [:f] }
   etag { nil  }
 
   def fresh
-    render plain: "stale" if stale?(etag: '123', template: false)
+    render plain: "stale" if stale?(etag: "123", template: false)
   end
 
   def array
@@ -17,14 +22,18 @@ class TestControllerWithExtraEtags < ActionController::Base
   end
 
   def strong
-    render plain: "stale" if stale?(strong_etag: 'strong')
+    render plain: "stale" if stale?(strong_etag: "strong", template: false)
   end
 
   def with_template
-    if stale? template: 'test/hello_world'
-      render plain: 'stale'
+    if stale? template: "test/hello_world"
+      render plain: "stale"
     end
   end
+
+  def with_implicit_template
+    fresh_when(etag: "123")
+  end
 end
 
 class ImplicitRenderTestController < ActionController::Base
@@ -35,6 +44,14 @@ class ImplicitRenderTestController < ActionController::Base
   end
 end
 
+module Namespaced
+  class ImplicitRenderTestController < ActionController::Base
+    def hello_world
+      fresh_when(etag: "abc")
+    end
+  end
+end
+
 class TestController < ActionController::Base
   protect_from_forgery
 
@@ -56,8 +73,8 @@ class TestController < ActionController::Base
   end
 
   def conditional_hello
-    if stale?(:last_modified => Time.now.utc.beginning_of_day, :etag => [:foo, 123])
-      render :action => 'hello_world'
+    if stale?(last_modified: Time.now.utc.beginning_of_day, etag: [:foo, 123])
+      render action: "hello_world"
     end
   end
 
@@ -65,7 +82,7 @@ class TestController < ActionController::Base
     record = Struct.new(:updated_at, :cache_key).new(Time.now.utc.beginning_of_day, "foo/123")
 
     if stale?(record)
-      render :action => 'hello_world'
+      render action: "hello_world"
     end
   end
 
@@ -100,70 +117,69 @@ class TestController < ActionController::Base
     old_record = Struct.new(:updated_at, :cache_key).new(ts - 1.day, "bar/123")
 
     if stale?(Collection.new([record, old_record]))
-      render action: 'hello_world'
+      render action: "hello_world"
     end
   end
 
   def conditional_hello_with_expires_in
     expires_in 60.1.seconds
-    render :action => 'hello_world'
+    render action: "hello_world"
   end
 
   def conditional_hello_with_expires_in_with_public
-    expires_in 1.minute, :public => true
-    render :action => 'hello_world'
+    expires_in 1.minute, public: true
+    render action: "hello_world"
   end
 
   def conditional_hello_with_expires_in_with_must_revalidate
-    expires_in 1.minute, :must_revalidate => true
-    render :action => 'hello_world'
+    expires_in 1.minute, must_revalidate: true
+    render action: "hello_world"
   end
 
   def conditional_hello_with_expires_in_with_public_and_must_revalidate
-    expires_in 1.minute, :public => true, :must_revalidate => true
-    render :action => 'hello_world'
+    expires_in 1.minute, public: true, must_revalidate: true
+    render action: "hello_world"
   end
 
   def conditional_hello_with_expires_in_with_public_with_more_keys
-    expires_in 1.minute, :public => true, 's-maxage' => 5.hours
-    render :action => 'hello_world'
+    expires_in 1.minute, :public => true, "s-maxage" => 5.hours
+    render action: "hello_world"
   end
 
   def conditional_hello_with_expires_in_with_public_with_more_keys_old_syntax
-    expires_in 1.minute, :public => true, :private => nil, 's-maxage' => 5.hours
-    render :action => 'hello_world'
+    expires_in 1.minute, :public => true, :private => nil, "s-maxage" => 5.hours
+    render action: "hello_world"
   end
 
   def conditional_hello_with_expires_now
     expires_now
-    render :action => 'hello_world'
+    render action: "hello_world"
   end
 
   def conditional_hello_with_cache_control_headers
-    response.headers['Cache-Control'] = 'no-transform'
+    response.headers["Cache-Control"] = "no-transform"
     expires_now
-    render :action => 'hello_world'
+    render action: "hello_world"
   end
 
-  def respond_with_empty_body
-    render nothing: true
-  end
-
-  def conditional_hello_with_bangs
-    render :action => 'hello_world'
+  def conditional_hello_with_expires_and_confliciting_cache_control_headers
+    response.headers["Cache-Control"] = "no-cache, must-revalidate"
+    expires_now
+    render action: "hello_world"
   end
-  before_action :handle_last_modified_and_etags, :only=>:conditional_hello_with_bangs
 
-  def handle_last_modified_and_etags
-    fresh_when(:last_modified => Time.now.utc.beginning_of_day, :etag => [ :foo, 123 ])
+  def conditional_hello_without_expires_and_confliciting_cache_control_headers
+    response.headers["Cache-Control"] = "no-cache, must-revalidate"
+    render action: "hello_world"
   end
 
-  def head_with_status_hash
-    head status: :created
+  def conditional_hello_with_bangs
+    render action: "hello_world"
   end
+  before_action :handle_last_modified_and_etags, only: :conditional_hello_with_bangs
 
-  def head_with_hash_does_not_include_status
-    head warning: :deprecated
+  def handle_last_modified_and_etags
+    fresh_when(last_modified: Time.now.utc.beginning_of_day, etag: [ :foo, 123 ])
   end
 
   def head_created
@@ -171,19 +187,19 @@ class TestController < ActionController::Base
   end
 
   def head_created_with_application_json_content_type
-    head :created, :content_type => "application/json"
+    head :created, content_type: "application/json"
   end
 
   def head_ok_with_image_png_content_type
-    head :ok, :content_type => "image/png"
+    head :ok, content_type: "image/png"
   end
 
   def head_with_location_header
-    head :ok, :location => "/foo"
+    head :ok, location: "/foo"
   end
 
   def head_with_location_object
-    head :ok, :location => Customer.new("david", 1)
+    head :ok, location: Customer.new("david", 1)
   end
 
   def head_with_symbolic_status
@@ -199,20 +215,20 @@ class TestController < ActionController::Base
   end
 
   def head_with_custom_header
-    head :ok, :x_custom_header => "something"
+    head :ok, x_custom_header: "something"
   end
 
   def head_with_www_authenticate_header
-    head :ok, 'WWW-Authenticate' => 'something'
+    head :ok, "WWW-Authenticate" => "something"
   end
 
   def head_with_status_code_first
-    head :forbidden, :x_custom_header => "something"
+    head :forbidden, x_custom_header: "something"
   end
 
   def head_and_return
-    head :ok and return
-    raise 'should not reach this line'
+    head(:ok) && return
+    raise "should not reach this line"
   end
 
   def head_with_no_content
@@ -232,7 +248,7 @@ class TestController < ActionController::Base
 
     def determine_layout
       case action_name
-        when "hello_world", "layout_test", "rendering_without_layout",
+      when "hello_world", "layout_test", "rendering_without_layout",
              "rendering_nothing_on_layout", "render_text_hello_world",
              "render_text_hello_world_with_layout",
              "hello_world_with_layout_false",
@@ -242,22 +258,35 @@ class TestController < ActionController::Base
              "render_with_explicit_string_template",
              "update_page", "update_page_with_instance_variables"
 
-          "layouts/standard"
-        when "action_talk_to_layout", "layout_overriding_layout"
-          "layouts/talk_from_action"
-        when "render_implicit_html_template_from_xhr_request"
-          (request.xhr? ? 'layouts/xhr' : 'layouts/standard')
+        "layouts/standard"
+      when "action_talk_to_layout", "layout_overriding_layout"
+        "layouts/talk_from_action"
+      when "render_implicit_html_template_from_xhr_request"
+        (request.xhr? ? "layouts/xhr" : "layouts/standard")
       end
     end
 end
 
+module TemplateModificationHelper
+  private
+    def modify_template(name)
+      path = File.expand_path("../fixtures/#{name}.erb", __dir__)
+      original = File.read(path)
+      File.write(path, "#{original} Modified!")
+      ActionView::LookupContext::DetailsKey.clear
+      yield
+    ensure
+      File.write(path, original)
+    end
+end
+
 class MetalTestController < ActionController::Metal
   include AbstractController::Rendering
   include ActionView::Rendering
   include ActionController::Rendering
 
   def accessing_logger_in_template
-    render :inline =>  "<%= logger.class %>"
+    render inline: "<%= logger.class %>"
   end
 end
 
@@ -271,14 +300,14 @@ class ExpiresInRenderTest < ActionController::TestCase
 
   def test_dynamic_render_with_file
     # This is extremely bad, but should be possible to do.
-    assert File.exist?(File.join(File.dirname(__FILE__), '../../test/abstract_unit.rb'))
+    assert File.exist?(File.expand_path("../../test/abstract_unit.rb", __dir__))
     response = get :dynamic_render_with_file, params: { id: '../\\../test/abstract_unit.rb' }
-    assert_equal File.read(File.join(File.dirname(__FILE__), '../../test/abstract_unit.rb')),
+    assert_equal File.read(File.expand_path("../../test/abstract_unit.rb", __dir__)),
       response.body
   end
 
   def test_dynamic_render_with_absolute_path
-    file = Tempfile.new('name')
+    file = Tempfile.new("name")
     file.write "secrets!"
     file.flush
     assert_raises ActionView::MissingTemplate do
@@ -290,17 +319,16 @@ class ExpiresInRenderTest < ActionController::TestCase
   end
 
   def test_dynamic_render
-    assert File.exist?(File.join(File.dirname(__FILE__), '../../test/abstract_unit.rb'))
+    assert File.exist?(File.expand_path("../../test/abstract_unit.rb", __dir__))
     assert_raises ActionView::MissingTemplate do
       get :dynamic_render, params: { id: '../\\../test/abstract_unit.rb' }
     end
   end
 
   def test_permitted_dynamic_render_file_hash
-    skip "FIXME: this test passes on 4-2-stable but not master. Why?"
-    assert File.exist?(File.join(File.dirname(__FILE__), '../../test/abstract_unit.rb'))
+    assert File.exist?(File.expand_path("../../test/abstract_unit.rb", __dir__))
     response = get :dynamic_render_permit, params: { id: { file: '../\\../test/abstract_unit.rb' } }
-    assert_equal File.read(File.join(File.dirname(__FILE__), '../../test/abstract_unit.rb')),
+    assert_equal File.read(File.expand_path("../../test/abstract_unit.rb", __dir__)),
       response.body
   end
 
@@ -351,14 +379,18 @@ class ExpiresInRenderTest < ActionController::TestCase
     assert_match(/no-transform/, @response.headers["Cache-Control"])
   end
 
-  def test_render_nothing_deprecated
-    assert_deprecated do
-      get :respond_with_empty_body
-    end
+  def test_expires_now_with_conflicting_cache_control_headers
+    get :conditional_hello_with_expires_and_confliciting_cache_control_headers
+    assert_equal "no-cache", @response.headers["Cache-Control"]
+  end
+
+  def test_no_expires_now_with_conflicting_cache_control_headers
+    get :conditional_hello_without_expires_and_confliciting_cache_control_headers
+    assert_equal "no-cache", @response.headers["Cache-Control"]
   end
 
   def test_date_header_when_expires_in
-    time = Time.mktime(2011,10,30)
+    time = Time.mktime(2011, 10, 30)
     Time.stub :now, time do
       get :conditional_hello_with_expires_in
       assert_equal Time.now.httpdate, @response.headers["Date"]
@@ -376,7 +408,7 @@ class LastModifiedRenderTest < ActionController::TestCase
 
   def test_responds_with_last_modified
     get :conditional_hello
-    assert_equal @last_modified, @response.headers['Last-Modified']
+    assert_equal @last_modified, @response.headers["Last-Modified"]
   end
 
   def test_request_not_modified
@@ -384,7 +416,7 @@ class LastModifiedRenderTest < ActionController::TestCase
     get :conditional_hello
     assert_equal 304, @response.status.to_i
     assert @response.body.blank?
-    assert_equal @last_modified, @response.headers['Last-Modified']
+    assert_equal @last_modified, @response.headers["Last-Modified"]
   end
 
   def test_request_not_modified_but_etag_differs
@@ -395,16 +427,16 @@ class LastModifiedRenderTest < ActionController::TestCase
   end
 
   def test_request_modified
-    @request.if_modified_since = 'Thu, 16 Jul 2008 00:00:00 GMT'
+    @request.if_modified_since = "Thu, 16 Jul 2008 00:00:00 GMT"
     get :conditional_hello
     assert_equal 200, @response.status.to_i
     assert @response.body.present?
-    assert_equal @last_modified, @response.headers['Last-Modified']
+    assert_equal @last_modified, @response.headers["Last-Modified"]
   end
 
   def test_responds_with_last_modified_with_record
     get :conditional_hello_with_record
-    assert_equal @last_modified, @response.headers['Last-Modified']
+    assert_equal @last_modified, @response.headers["Last-Modified"]
   end
 
   def test_request_not_modified_with_record
@@ -413,7 +445,7 @@ class LastModifiedRenderTest < ActionController::TestCase
     assert_equal 304, @response.status.to_i
     assert @response.body.blank?
     assert_not_nil @response.etag
-    assert_equal @last_modified, @response.headers['Last-Modified']
+    assert_equal @last_modified, @response.headers["Last-Modified"]
   end
 
   def test_request_not_modified_but_etag_differs_with_record
@@ -424,16 +456,16 @@ class LastModifiedRenderTest < ActionController::TestCase
   end
 
   def test_request_modified_with_record
-    @request.if_modified_since = 'Thu, 16 Jul 2008 00:00:00 GMT'
+    @request.if_modified_since = "Thu, 16 Jul 2008 00:00:00 GMT"
     get :conditional_hello_with_record
     assert_equal 200, @response.status.to_i
     assert @response.body.present?
-    assert_equal @last_modified, @response.headers['Last-Modified']
+    assert_equal @last_modified, @response.headers["Last-Modified"]
   end
 
   def test_responds_with_last_modified_with_collection_of_records
     get :conditional_hello_with_collection_of_records
-    assert_equal @last_modified, @response.headers['Last-Modified']
+    assert_equal @last_modified, @response.headers["Last-Modified"]
   end
 
   def test_request_not_modified_with_collection_of_records
@@ -441,7 +473,7 @@ class LastModifiedRenderTest < ActionController::TestCase
     get :conditional_hello_with_collection_of_records
     assert_equal 304, @response.status.to_i
     assert @response.body.blank?
-    assert_equal @last_modified, @response.headers['Last-Modified']
+    assert_equal @last_modified, @response.headers["Last-Modified"]
   end
 
   def test_request_not_modified_but_etag_differs_with_collection_of_records
@@ -452,16 +484,16 @@ class LastModifiedRenderTest < ActionController::TestCase
   end
 
   def test_request_modified_with_collection_of_records
-    @request.if_modified_since = 'Thu, 16 Jul 2008 00:00:00 GMT'
+    @request.if_modified_since = "Thu, 16 Jul 2008 00:00:00 GMT"
     get :conditional_hello_with_collection_of_records
     assert_equal 200, @response.status.to_i
     assert @response.body.present?
-    assert_equal @last_modified, @response.headers['Last-Modified']
+    assert_equal @last_modified, @response.headers["Last-Modified"]
   end
 
   def test_request_with_bang_gets_last_modified
     get :conditional_hello_with_bangs
-    assert_equal @last_modified, @response.headers['Last-Modified']
+    assert_equal @last_modified, @response.headers["Last-Modified"]
     assert_response :success
   end
 
@@ -480,13 +512,14 @@ end
 
 class EtagRenderTest < ActionController::TestCase
   tests TestControllerWithExtraEtags
+  include TemplateModificationHelper
 
   def test_strong_etag
-    @request.if_none_match = strong_etag(['strong', 'ab', :cde, [:f]])
+    @request.if_none_match = strong_etag(["strong", "ab", :cde, [:f]])
     get :strong
     assert_response :not_modified
 
-    @request.if_none_match = '*'
+    @request.if_none_match = "*"
     get :strong
     assert_response :not_modified
 
@@ -494,13 +527,13 @@ class EtagRenderTest < ActionController::TestCase
     get :strong
     assert_response :ok
 
-    @request.if_none_match = weak_etag(['strong', 'ab', :cde, [:f]])
+    @request.if_none_match = weak_etag(["strong", "ab", :cde, [:f]])
     get :strong
     assert_response :ok
   end
 
   def test_multiple_etags
-    @request.if_none_match = weak_etag(["123", 'ab', :cde, [:f]])
+    @request.if_none_match = weak_etag(["123", "ab", :cde, [:f]])
     get :fresh
     assert_response :not_modified
 
@@ -510,7 +543,7 @@ class EtagRenderTest < ActionController::TestCase
   end
 
   def test_array
-    @request.if_none_match = weak_etag([%w(1 2 3), 'ab', :cde, [:f]])
+    @request.if_none_match = weak_etag([%w(1 2 3), "ab", :cde, [:f]])
     get :array
     assert_response :not_modified
 
@@ -528,20 +561,28 @@ class EtagRenderTest < ActionController::TestCase
     get :with_template
     assert_response :not_modified
 
-    # Modify the template digest
-    path = File.expand_path('../../fixtures/test/hello_world.erb', __FILE__)
-    old = File.read(path)
+    modify_template("test/hello_world") do
+      request.if_none_match = etag
+      get :with_template
+      assert_response :ok
+      assert_not_equal etag, @response.etag
+    end
+  end
 
-    begin
-      File.write path, 'foo'
-      ActionView::LookupContext::DetailsKey.clear
+  def test_etag_reflects_implicit_template_digest
+    get :with_implicit_template
+    assert_response :ok
+    assert_not_nil etag = @response.etag
 
+    request.if_none_match = etag
+    get :with_implicit_template
+    assert_response :not_modified
+
+    modify_template("test/with_implicit_template") do
       request.if_none_match = etag
-      get :with_template
+      get :with_implicit_template
       assert_response :ok
       assert_not_equal etag, @response.etag
-    ensure
-      File.write path, old
     end
   end
 
@@ -551,10 +592,32 @@ class EtagRenderTest < ActionController::TestCase
     end
 
     def strong_etag(record)
-      %("#{Digest::MD5.hexdigest(ActiveSupport::Cache.expand_cache_key(record))}")
+      %("#{ActiveSupport::Digest.hexdigest(ActiveSupport::Cache.expand_cache_key(record))}")
     end
 end
 
+class NamespacedEtagRenderTest < ActionController::TestCase
+  tests Namespaced::ImplicitRenderTestController
+  include TemplateModificationHelper
+
+  def test_etag_reflects_template_digest
+    get :hello_world
+    assert_response :ok
+    assert_not_nil etag = @response.etag
+
+    request.if_none_match = etag
+    get :hello_world
+    assert_response :not_modified
+
+    modify_template("namespaced/implicit_render_test/hello_world") do
+      request.if_none_match = etag
+      get :hello_world
+      assert_response :ok
+      assert_not_equal etag, @response.etag
+    end
+  end
+end
+
 class MetalRenderTest < ActionController::TestCase
   tests MetalTestController
 
@@ -564,10 +627,22 @@ class MetalRenderTest < ActionController::TestCase
   end
 end
 
+class ActionControllerRenderTest < ActionController::TestCase
+  class MinimalController < ActionController::Metal
+    include AbstractController::Rendering
+    include ActionController::Rendering
+  end
+
+  def test_direct_render_to_string_with_body
+    mc = MinimalController.new
+    assert_equal "Hello world!", mc.render_to_string(body: ["Hello world!"])
+  end
+end
+
 class ActionControllerBaseRenderTest < ActionController::TestCase
   def test_direct_render_to_string
     ac = ActionController::Base.new()
-    assert_equal "Hello world!", ac.render_to_string(template: 'test/hello_world')
+    assert_equal "Hello world!", ac.render_to_string(template: "test/hello_world")
   end
 end
 
@@ -593,7 +668,7 @@ class ImplicitRenderTest < ActionController::TestCase
 
   def test_implicit_unknown_format_response
     assert_raises(ActionController::UnknownFormat) do
-      get :empty_action_with_template, format: 'json'
+      get :empty_action_with_template, format: "json"
     end
   end
 end
@@ -611,19 +686,6 @@ class HeadRenderTest < ActionController::TestCase
     assert_response :created
   end
 
-  def test_passing_hash_to_head_as_first_parameter_deprecated
-    assert_deprecated do
-      get :head_with_status_hash
-    end
-  end
-
-  def test_head_with_default_value_is_deprecated
-    assert_deprecated do
-      get :head_with_hash_does_not_include_status
-      assert_response :ok
-    end
-  end
-
   def test_head_created_with_application_json_content_type
     post :head_created_with_application_json_content_type
     assert @response.body.blank?
@@ -651,7 +713,7 @@ class HeadRenderTest < ActionController::TestCase
         resources :customers
 
         ActiveSupport::Deprecation.silence do
-          get ':controller/:action'
+          get ":controller/:action"
         end
       end
 
@@ -687,7 +749,7 @@ class HeadRenderTest < ActionController::TestCase
 
     get :head_with_symbolic_status, params: { status: "no_content" }
     assert_equal 204, @response.status
-    assert !@response.headers.include?('Content-Length')
+    assert_not_includes @response.headers, "Content-Length"
     assert_response :no_content
 
     Rack::Utils::SYMBOL_TO_STATUS_CODE.each do |status, code|
@@ -738,7 +800,7 @@ class HttpCacheForeverTest < ActionController::TestCase
   class HttpCacheForeverController < ActionController::Base
     def cache_me_forever
       http_cache_forever(public: params[:public]) do
-        render plain: 'hello'
+        render plain: "hello"
       end
     end
   end
@@ -746,7 +808,7 @@ class HttpCacheForeverTest < ActionController::TestCase
   tests HttpCacheForeverController
 
   def test_cache_with_public
-    get :cache_me_forever, params: {public: true}
+    get :cache_me_forever, params: { public: true }
     assert_response :ok
     assert_equal "max-age=#{100.years}, public", @response.headers["Cache-Control"]
     assert_not_nil @response.etag
@@ -765,7 +827,7 @@ class HttpCacheForeverTest < ActionController::TestCase
     get :cache_me_forever
     assert_response :ok
 
-    @request.if_modified_since = @response.headers['Last-Modified']
+    @request.if_modified_since = @response.headers["Last-Modified"]
     get :cache_me_forever
     assert_response :not_modified
   end
diff --git a/actionpack/test/controller/render_xml_test.rb b/actionpack/test/controller/render_xml_test.rb
index 137236c496..a72d14e4bb 100644
--- a/actionpack/test/controller/render_xml_test.rb
+++ b/actionpack/test/controller/render_xml_test.rb
@@ -1,6 +1,8 @@
-require 'abstract_unit'
-require 'controller/fake_models'
-require 'pathname'
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "controller/fake_models"
+require "pathname"
 
 class RenderXmlTest < ActionController::TestCase
   class XmlRenderable
@@ -14,31 +16,31 @@ class RenderXmlTest < ActionController::TestCase
     protect_from_forgery
 
     def self.controller_path
-      'test'
+      "test"
     end
 
     def render_with_location
-      render :xml => "<hello/>", :location => "http://example.com", :status => 201
+      render xml: "<hello/>", location: "http://example.com", status: 201
     end
 
     def render_with_object_location
       customer = Customer.new("Some guy", 1)
-      render :xml => "<customer/>", :location => customer, :status => :created
+      render xml: "<customer/>", location: customer, status: :created
     end
 
     def render_with_to_xml
-      render :xml => XmlRenderable.new
+      render xml: XmlRenderable.new
     end
 
     def formatted_xml_erb
     end
 
     def render_xml_with_custom_content_type
-      render :xml => "<blah/>", :content_type => "application/atomsvc+xml"
+      render xml: "<blah/>", content_type: "application/atomsvc+xml"
     end
 
     def render_xml_with_custom_options
-      render :xml => XmlRenderable.new, :root => "i-am-THE-xml"
+      render xml: XmlRenderable.new, root: "i-am-THE-xml"
     end
   end
 
@@ -74,7 +76,7 @@ class RenderXmlTest < ActionController::TestCase
         resources :customers
 
         ActiveSupport::Deprecation.silence do
-          get ':controller/:action'
+          get ":controller/:action"
         end
       end
 
@@ -85,7 +87,7 @@ class RenderXmlTest < ActionController::TestCase
 
   def test_should_render_formatted_xml_erb_template
     get :formatted_xml_erb, format: :xml
-    assert_equal '<test>passed formatted xml erb</test>', @response.body
+    assert_equal "<test>passed formatted xml erb</test>", @response.body
   end
 
   def test_should_render_xml_but_keep_custom_content_type
@@ -94,7 +96,7 @@ class RenderXmlTest < ActionController::TestCase
   end
 
   def test_should_use_implicit_content_type
-    get :implicit_content_type, format: 'atom'
+    get :implicit_content_type, format: "atom"
     assert_equal Mime[:atom], @response.content_type
   end
 end
diff --git a/actionpack/test/controller/renderer_test.rb b/actionpack/test/controller/renderer_test.rb
index 372c09bc23..ae8330e029 100644
--- a/actionpack/test/controller/renderer_test.rb
+++ b/actionpack/test/controller/renderer_test.rb
@@ -1,98 +1,132 @@
-require 'abstract_unit'
+# frozen_string_literal: true
+
+require "abstract_unit"
 
 class RendererTest < ActiveSupport::TestCase
-  test 'action controller base has a renderer' do
+  test "action controller base has a renderer" do
     assert ActionController::Base.renderer
   end
 
-  test 'creating with a controller' do
+  test "creating with a controller" do
     controller = CommentsController
     renderer   = ActionController::Renderer.for controller
 
     assert_equal controller, renderer.controller
   end
 
-  test 'creating from a controller' do
+  test "creating from a controller" do
     controller = AccountsController
     renderer   = controller.renderer
 
     assert_equal controller, renderer.controller
   end
 
-  test 'rendering with a class renderer' do
+  test "creating with new defaults" do
     renderer = ApplicationController.renderer
-    content  = renderer.render template: 'ruby_template'
 
-    assert_equal 'Hello from Ruby code', content
+    new_defaults = { https: true }
+    new_renderer = renderer.with_defaults(new_defaults).new
+    content = new_renderer.render(inline: "<%= request.ssl? %>")
+
+    assert_equal "true", content
   end
 
-  test 'rendering with an instance renderer' do
+  test "rendering with a class renderer" do
+    renderer = ApplicationController.renderer
+    content  = renderer.render template: "ruby_template"
+
+    assert_equal "Hello from Ruby code", content
+  end
+
+  test "rendering with an instance renderer" do
     renderer = ApplicationController.renderer.new
-    content  = renderer.render file: 'test/hello_world'
+    content  = renderer.render file: "test/hello_world"
 
-    assert_equal 'Hello world!', content
+    assert_equal "Hello world!", content
   end
 
-  test 'rendering with a controller class' do
-    assert_equal 'Hello world!', ApplicationController.render('test/hello_world')
+  test "rendering with a controller class" do
+    assert_equal "Hello world!", ApplicationController.render("test/hello_world")
   end
 
-  test 'rendering with locals' do
+  test "rendering with locals" do
     renderer = ApplicationController.renderer
-    content  = renderer.render template: 'test/render_file_with_locals',
-                               locals: { secret: 'bar' }
+    content  = renderer.render template: "test/render_file_with_locals",
+                               locals: { secret: "bar" }
 
     assert_equal "The secret is bar\n", content
   end
 
-  test 'rendering with assigns' do
+  test "rendering with assigns" do
     renderer = ApplicationController.renderer
-    content  = renderer.render template: 'test/render_file_with_ivar',
-                               assigns: { secret: 'foo' }
+    content  = renderer.render template: "test/render_file_with_ivar",
+                               assigns: { secret: "foo" }
 
     assert_equal "The secret is foo\n", content
   end
 
-  test 'rendering with custom env' do
-    renderer = ApplicationController.renderer.new method: 'post'
-    content  = renderer.render inline: '<%= request.post? %>'
+  test "rendering with custom env" do
+    renderer = ApplicationController.renderer.new method: "post"
+    content  = renderer.render inline: "<%= request.post? %>"
+
+    assert_equal "true", content
+  end
+
+  test "rendering with custom env using a key that is not in RACK_KEY_TRANSLATION" do
+    value    = "warden is here"
+    renderer = ApplicationController.renderer.new warden: value
+    content  = renderer.render inline: "<%= request.env['warden'] %>"
 
-    assert_equal 'true', content
+    assert_equal value, content
   end
 
-  test 'rendering with defaults' do
+  test "rendering with defaults" do
     renderer = ApplicationController.renderer.new https: true
-    content = renderer.render inline: '<%= request.ssl? %>'
+    content = renderer.render inline: "<%= request.ssl? %>"
 
-    assert_equal 'true', content
+    assert_equal "true", content
   end
 
-  test 'same defaults from the same controller' do
+  test "same defaults from the same controller" do
     renderer_defaults = ->(controller) { controller.renderer.defaults }
 
     assert_equal renderer_defaults[AccountsController], renderer_defaults[AccountsController]
     assert_equal renderer_defaults[AccountsController], renderer_defaults[CommentsController]
   end
 
-  test 'rendering with different formats' do
-    html = 'Hello world!'
+  test "rendering with different formats" do
+    html = "Hello world!"
     xml  = "<p>Hello world!</p>\n"
 
-    assert_equal html, render['respond_to/using_defaults']
-    assert_equal xml,  render['respond_to/using_defaults.xml.builder']
-    assert_equal xml,  render['respond_to/using_defaults', formats: :xml]
+    assert_equal html, render["respond_to/using_defaults"]
+    assert_equal xml,  render["respond_to/using_defaults.xml.builder"]
+    assert_equal xml,  render["respond_to/using_defaults", formats: :xml]
   end
 
-  test 'rendering with helpers' do
+  test "rendering with helpers" do
     assert_equal "<p>1\n<br />2</p>", render[inline: '<%= simple_format "1\n2" %>']
   end
 
-  test 'rendering with user specified defaults' do
-    ApplicationController.renderer.defaults.merge!({ hello: 'hello', https: true })
+  test "rendering with user specified defaults" do
+    ApplicationController.renderer.defaults.merge!(hello: "hello", https: true)
     renderer = ApplicationController.renderer.new
-    content = renderer.render inline: '<%= request.ssl? %>'
+    content = renderer.render inline: "<%= request.ssl? %>"
+
+    assert_equal "true", content
+  end
+
+  test "return valid asset url with defaults" do
+    renderer = ApplicationController.renderer
+    content  = renderer.render inline: "<%= asset_url 'asset.jpg' %>"
+
+    assert_equal "http://example.org/asset.jpg", content
+  end
+
+  test "return valid asset url when https is true" do
+    renderer = ApplicationController.renderer.new https: true
+    content  = renderer.render inline: "<%= asset_url 'asset.jpg' %>"
 
-    assert_equal 'true', content
+    assert_equal "https://example.org/asset.jpg", content
   end
 
   private
diff --git a/actionpack/test/controller/renderers_test.rb b/actionpack/test/controller/renderers_test.rb
index e6c2e4636e..d92de6f5d5 100644
--- a/actionpack/test/controller/renderers_test.rb
+++ b/actionpack/test/controller/renderers_test.rb
@@ -1,6 +1,8 @@
-require 'abstract_unit'
-require 'controller/fake_models'
-require 'active_support/logger'
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "controller/fake_models"
+require "active_support/logger"
 
 class RenderersTest < ActionController::TestCase
   class XmlRenderable
@@ -10,14 +12,14 @@ class RenderersTest < ActionController::TestCase
     end
   end
   class JsonRenderable
-    def as_json(options={})
-      hash = { :a => :b, :c => :d, :e => :f }
+    def as_json(options = {})
+      hash = { a: :b, c: :d, e: :f }
       hash.except!(*options[:except]) if options[:except]
       hash
     end
 
     def to_json(options = {})
-      super :except => [:c, :e]
+      super except: [:c, :e]
     end
   end
   class CsvRenderable
@@ -26,9 +28,8 @@ class RenderersTest < ActionController::TestCase
     end
   end
   class TestController < ActionController::Base
-
     def render_simon_says
-      render :simon => "foo"
+      render simon: "foo"
     end
 
     def respond_to_mime
@@ -36,7 +37,7 @@ class RenderersTest < ActionController::TestCase
         type.json do
           render json: JsonRenderable.new
         end
-        type.js   { render json: 'JS', callback: 'alert' }
+        type.js   { render json: "JS", callback: "alert" }
         type.csv  { render csv: CsvRenderable.new    }
         type.xml  { render xml: XmlRenderable.new     }
         type.html { render body: "HTML"    }
@@ -70,7 +71,7 @@ class RenderersTest < ActionController::TestCase
 
   def test_raises_missing_template_no_renderer
     assert_raise ActionView::MissingTemplate do
-      get :respond_to_mime, format: 'csv'
+      get :respond_to_mime, format: "csv"
     end
     assert_equal Mime[:csv], @response.content_type
     assert_equal "", @response.body
@@ -81,7 +82,7 @@ class RenderersTest < ActionController::TestCase
       send_data value.to_csv, type: Mime[:csv]
     end
     @request.accept = "text/csv"
-    get :respond_to_mime, format: 'csv'
+    get :respond_to_mime, format: "csv"
     assert_equal Mime[:csv], @response.content_type
     assert_equal "c,s,v", @response.body
   ensure
diff --git a/actionpack/test/controller/request/test_request_test.rb b/actionpack/test/controller/request/test_request_test.rb
index e5d698d5c2..b8d86696de 100644
--- a/actionpack/test/controller/request/test_request_test.rb
+++ b/actionpack/test/controller/request/test_request_test.rb
@@ -1,23 +1,42 @@
-require 'abstract_unit'
-require 'stringio'
+# frozen_string_literal: true
 
-class ActionController::TestRequestTest < ActionController::TestCase
+require "abstract_unit"
+require "stringio"
 
+class ActionController::TestRequestTest < ActionController::TestCase
   def test_test_request_has_session_options_initialized
     assert @request.session_options
   end
 
-  ActionDispatch::Session::AbstractStore::DEFAULT_OPTIONS.each_key do |option|
-    test "rack default session options #{option} exists in session options and is default" do
-      assert_equal(ActionDispatch::Session::AbstractStore::DEFAULT_OPTIONS[option],
-                   @request.session_options[option],
-                   "Missing rack session default option #{option} in request.session_options")
+  def test_mutating_session_options_does_not_affect_default_options
+    @request.session_options[:myparam] = 123
+    assert_nil ActionController::TestSession::DEFAULT_OPTIONS[:myparam]
+  end
+
+  def test_content_length_has_bytes_count_value
+    non_ascii_parameters = { data: { content: "Latin + Кириллица" } }
+    @request.set_header "REQUEST_METHOD", "POST"
+    @request.set_header "CONTENT_TYPE", "application/json"
+    @request.assign_parameters(@routes, "test", "create", non_ascii_parameters,
+                               "/test", [:data, :controller, :action])
+    assert_equal(StringIO.new(non_ascii_parameters.to_json).length.to_s,
+                 @request.get_header("CONTENT_LENGTH"))
+  end
+
+  ActionDispatch::Session::AbstractStore::DEFAULT_OPTIONS.each_pair do |key, value|
+    test "rack default session options #{key} exists in session options and is default" do
+      if value.nil?
+        assert_nil(@request.session_options[key],
+                   "Missing rack session default option #{key} in request.session_options")
+      else
+        assert_equal(value, @request.session_options[key],
+                     "Missing rack session default option #{key} in request.session_options")
+      end
     end
 
-    test "rack default session options #{option} exists in session options" do
-      assert(@request.session_options.has_key?(option),
-                   "Missing rack session option #{option} in request.session_options")
+    test "rack default session options #{key} exists in session options" do
+      assert(@request.session_options.has_key?(key),
+                   "Missing rack session option #{key} in request.session_options")
     end
   end
-
 end
diff --git a/actionpack/test/controller/request_forgery_protection_test.rb b/actionpack/test/controller/request_forgery_protection_test.rb
index d3f2ec6aa1..4822d85bcb 100644
--- a/actionpack/test/controller/request_forgery_protection_test.rb
+++ b/actionpack/test/controller/request_forgery_protection_test.rb
@@ -1,42 +1,61 @@
-require 'abstract_unit'
+# frozen_string_literal: true
+
+require "abstract_unit"
 require "active_support/log_subscriber/test_helper"
+require "active_support/messages/rotation_configuration"
 
 # common controller actions
 module RequestForgeryProtectionActions
   def index
-    render :inline => "<%= form_tag('/') {} %>"
+    render inline: "<%= form_tag('/') {} %>"
   end
 
   def show_button
-    render :inline => "<%= button_to('New', '/') %>"
+    render inline: "<%= button_to('New', '/') %>"
   end
 
   def unsafe
-    render plain: 'pwn'
+    render plain: "pwn"
   end
 
   def meta
-    render :inline => "<%= csrf_meta_tags %>"
+    render inline: "<%= csrf_meta_tags %>"
   end
 
   def form_for_remote
-    render :inline => "<%= form_for(:some_resource, :remote => true ) {} %>"
+    render inline: "<%= form_for(:some_resource, :remote => true ) {} %>"
   end
 
   def form_for_remote_with_token
-    render :inline => "<%= form_for(:some_resource, :remote => true, :authenticity_token => true ) {} %>"
+    render inline: "<%= form_for(:some_resource, :remote => true, :authenticity_token => true ) {} %>"
   end
 
   def form_for_with_token
-    render :inline => "<%= form_for(:some_resource, :authenticity_token => true ) {} %>"
+    render inline: "<%= form_for(:some_resource, :authenticity_token => true ) {} %>"
   end
 
   def form_for_remote_with_external_token
-    render :inline => "<%= form_for(:some_resource, :remote => true, :authenticity_token => 'external_token') {} %>"
+    render inline: "<%= form_for(:some_resource, :remote => true, :authenticity_token => 'external_token') {} %>"
+  end
+
+  def form_with_remote
+    render inline: "<%= form_with(scope: :some_resource) {} %>"
+  end
+
+  def form_with_remote_with_token
+    render inline: "<%= form_with(scope: :some_resource, authenticity_token: true) {} %>"
+  end
+
+  def form_with_local_with_token
+    render inline: "<%= form_with(scope: :some_resource, local: true, authenticity_token: true) {} %>"
+  end
+
+  def form_with_remote_with_external_token
+    render inline: "<%= form_with(scope: :some_resource, authenticity_token: 'external_token') {} %>"
   end
 
   def same_origin_js
-    render js: 'foo();'
+    render js: "foo();"
   end
 
   def negotiate_same_origin
@@ -52,30 +71,29 @@ module RequestForgeryProtectionActions
   def negotiate_cross_origin
     negotiate_same_origin
   end
-
 end
 
 # sample controllers
 class RequestForgeryProtectionControllerUsingResetSession < ActionController::Base
   include RequestForgeryProtectionActions
-  protect_from_forgery :only => %w(index meta same_origin_js negotiate_same_origin), :with => :reset_session
+  protect_from_forgery only: %w(index meta same_origin_js negotiate_same_origin), with: :reset_session
 end
 
 class RequestForgeryProtectionControllerUsingException < ActionController::Base
   include RequestForgeryProtectionActions
-  protect_from_forgery :only => %w(index meta same_origin_js negotiate_same_origin), :with => :exception
+  protect_from_forgery only: %w(index meta same_origin_js negotiate_same_origin), with: :exception
 end
 
 class RequestForgeryProtectionControllerUsingNullSession < ActionController::Base
-  protect_from_forgery :with => :null_session
+  protect_from_forgery with: :null_session
 
   def signed
-    cookies.signed[:foo] = 'bar'
+    cookies.signed[:foo] = "bar"
     head :ok
   end
 
   def encrypted
-    cookies.encrypted[:foo] = 'bar'
+    cookies.encrypted[:foo] = "bar"
     head :ok
   end
 
@@ -90,46 +108,45 @@ class PrependProtectForgeryBaseController < ActionController::Base
   attr_accessor :called_callbacks
 
   def index
-    render inline: 'OK'
+    render inline: "OK"
   end
 
-  protected
-
-  def add_called_callback(name)
-    @called_callbacks ||= []
-    @called_callbacks << name
-  end
+  private
 
+    def add_called_callback(name)
+      @called_callbacks ||= []
+      @called_callbacks << name
+    end
 
-  def custom_action
-    add_called_callback("custom_action")
-  end
+    def custom_action
+      add_called_callback("custom_action")
+    end
 
-  def verify_authenticity_token
-    add_called_callback("verify_authenticity_token")
-  end
+    def verify_authenticity_token
+      add_called_callback("verify_authenticity_token")
+    end
 end
 
 class FreeCookieController < RequestForgeryProtectionControllerUsingResetSession
   self.allow_forgery_protection = false
 
   def index
-    render :inline => "<%= form_tag('/') {} %>"
+    render inline: "<%= form_tag('/') {} %>"
   end
 
   def show_button
-    render :inline => "<%= button_to('New', '/') %>"
+    render inline: "<%= button_to('New', '/') %>"
   end
 end
 
 class CustomAuthenticityParamController < RequestForgeryProtectionControllerUsingResetSession
   def form_authenticity_param
-    'foobar'
+    "foobar"
   end
 end
 
 class PerFormTokensController < ActionController::Base
-  protect_from_forgery :with => :exception
+  protect_from_forgery with: :exception
   self.per_form_csrf_tokens = true
 
   def index
@@ -141,18 +158,25 @@ class PerFormTokensController < ActionController::Base
   end
 
   def post_one
-    render plain: ''
+    render plain: ""
   end
 
   def post_two
-    render plain: ''
+    render plain: ""
   end
 end
 
+class SkipProtectionController < ActionController::Base
+  include RequestForgeryProtectionActions
+  protect_from_forgery with: :exception
+  skip_forgery_protection if: :skip_requested
+  attr_accessor :skip_requested
+end
+
 # common test methods
 module RequestForgeryProtectionTests
   def setup
-    @token = Base64.strict_encode64('railstestrailstestrailstestrails')
+    @token = Base64.strict_encode64("railstestrailstestrailstestrails")
     @old_request_forgery_protection_token = ActionController::Base.request_forgery_protection_token
     ActionController::Base.request_forgery_protection_token = :custom_authenticity_token
   end
@@ -166,7 +190,7 @@ module RequestForgeryProtectionTests
       assert_not_blocked do
         get :index
       end
-      assert_select 'form>input[name=?][value=?]', 'custom_authenticity_token', @token
+      assert_select "form>input[name=?][value=?]", "custom_authenticity_token", @token
     end
   end
 
@@ -175,7 +199,7 @@ module RequestForgeryProtectionTests
       assert_not_blocked do
         get :show_button
       end
-      assert_select 'form>input[name=?][value=?]', 'custom_authenticity_token', @token
+      assert_select "form>input[name=?][value=?]", "custom_authenticity_token", @token
     end
   end
 
@@ -206,7 +230,7 @@ module RequestForgeryProtectionTests
       assert_not_blocked do
         get :form_for_remote_with_external_token
       end
-      assert_select 'form>input[name=?][value=?]', 'custom_authenticity_token', 'external_token'
+      assert_select "form>input[name=?][value=?]", "custom_authenticity_token", "external_token"
     ensure
       ActionView::Helpers::FormTagHelper.embed_authenticity_token_in_remote_forms = original
     end
@@ -216,7 +240,7 @@ module RequestForgeryProtectionTests
     assert_not_blocked do
       get :form_for_remote_with_external_token
     end
-    assert_select 'form>input[name=?][value=?]', 'custom_authenticity_token', 'external_token'
+    assert_select "form>input[name=?][value=?]", "custom_authenticity_token", "external_token"
   end
 
   def test_should_render_form_with_token_tag_if_remote_and_authenticity_token_requested
@@ -224,7 +248,7 @@ module RequestForgeryProtectionTests
       assert_not_blocked do
         get :form_for_remote_with_token
       end
-      assert_select 'form>input[name=?][value=?]', 'custom_authenticity_token', @token
+      assert_select "form>input[name=?][value=?]", "custom_authenticity_token", @token
     end
   end
 
@@ -233,7 +257,81 @@ module RequestForgeryProtectionTests
       assert_not_blocked do
         get :form_for_with_token
       end
-      assert_select 'form>input[name=?][value=?]', 'custom_authenticity_token', @token
+      assert_select "form>input[name=?][value=?]", "custom_authenticity_token", @token
+    end
+  end
+
+  def test_should_render_form_with_with_token_tag_if_remote
+    assert_not_blocked do
+      get :form_with_remote
+    end
+    assert_match(/authenticity_token/, response.body)
+  end
+
+  def test_should_render_form_with_without_token_tag_if_remote_and_embedding_token_is_off
+    original = ActionView::Helpers::FormTagHelper.embed_authenticity_token_in_remote_forms
+    begin
+      ActionView::Helpers::FormTagHelper.embed_authenticity_token_in_remote_forms = false
+      assert_not_blocked do
+        get :form_with_remote
+      end
+      assert_no_match(/authenticity_token/, response.body)
+    ensure
+      ActionView::Helpers::FormTagHelper.embed_authenticity_token_in_remote_forms = original
+    end
+  end
+
+  def test_should_render_form_with_with_token_tag_if_remote_and_external_authenticity_token_requested_and_embedding_is_on
+    original = ActionView::Helpers::FormTagHelper.embed_authenticity_token_in_remote_forms
+    begin
+      ActionView::Helpers::FormTagHelper.embed_authenticity_token_in_remote_forms = true
+      assert_not_blocked do
+        get :form_with_remote_with_external_token
+      end
+      assert_select "form>input[name=?][value=?]", "custom_authenticity_token", "external_token"
+    ensure
+      ActionView::Helpers::FormTagHelper.embed_authenticity_token_in_remote_forms = original
+    end
+  end
+
+  def test_should_render_form_with_with_token_tag_if_remote_and_external_authenticity_token_requested
+    assert_not_blocked do
+      get :form_with_remote_with_external_token
+    end
+    assert_select "form>input[name=?][value=?]", "custom_authenticity_token", "external_token"
+  end
+
+  def test_should_render_form_with_with_token_tag_if_remote_and_authenticity_token_requested
+    @controller.stub :form_authenticity_token, @token do
+      assert_not_blocked do
+        get :form_with_remote_with_token
+      end
+      assert_select "form>input[name=?][value=?]", "custom_authenticity_token", @token
+    end
+  end
+
+  def test_should_render_form_with_with_token_tag_with_authenticity_token_requested
+    @controller.stub :form_authenticity_token, @token do
+      assert_not_blocked do
+        get :form_with_local_with_token
+      end
+      assert_select "form>input[name=?][value=?]", "custom_authenticity_token", @token
+    end
+  end
+
+  def test_should_render_form_with_with_token_tag_if_remote_and_embedding_token_is_on
+    original = ActionView::Helpers::FormTagHelper.embed_authenticity_token_in_remote_forms
+    begin
+      ActionView::Helpers::FormTagHelper.embed_authenticity_token_in_remote_forms = true
+
+      @controller.stub :form_authenticity_token, @token do
+        assert_not_blocked do
+          get :form_with_remote
+        end
+      end
+      assert_select "form>input[name=?][value=?]", "custom_authenticity_token", @token
+    ensure
+      ActionView::Helpers::FormTagHelper.embed_authenticity_token_in_remote_forms = original
     end
   end
 
@@ -254,7 +352,7 @@ module RequestForgeryProtectionTests
   end
 
   def test_should_not_allow_post_without_token_irrespective_of_format
-    assert_blocked { post :index, format: 'xml' }
+    assert_blocked { post :index, format: "xml" }
   end
 
   def test_should_not_allow_patch_without_token
@@ -303,25 +401,25 @@ module RequestForgeryProtectionTests
 
   def test_should_allow_post_with_token_in_header
     session[:_csrf_token] = @token
-    @request.env['HTTP_X_CSRF_TOKEN'] = @token
+    @request.env["HTTP_X_CSRF_TOKEN"] = @token
     assert_not_blocked { post :index }
   end
 
   def test_should_allow_delete_with_token_in_header
     session[:_csrf_token] = @token
-    @request.env['HTTP_X_CSRF_TOKEN'] = @token
+    @request.env["HTTP_X_CSRF_TOKEN"] = @token
     assert_not_blocked { delete :index }
   end
 
   def test_should_allow_patch_with_token_in_header
     session[:_csrf_token] = @token
-    @request.env['HTTP_X_CSRF_TOKEN'] = @token
+    @request.env["HTTP_X_CSRF_TOKEN"] = @token
     assert_not_blocked { patch :index }
   end
 
   def test_should_allow_put_with_token_in_header
     session[:_csrf_token] = @token
-    @request.env['HTTP_X_CSRF_TOKEN'] = @token
+    @request.env["HTTP_X_CSRF_TOKEN"] = @token
     assert_not_blocked { put :index }
   end
 
@@ -330,7 +428,7 @@ module RequestForgeryProtectionTests
       session[:_csrf_token] = @token
       @controller.stub :form_authenticity_token, @token do
         assert_not_blocked do
-          @request.set_header 'HTTP_ORIGIN', 'http://test.host'
+          @request.set_header "HTTP_ORIGIN", "http://test.host"
           post :index, params: { custom_authenticity_token: @token }
         end
       end
@@ -348,16 +446,40 @@ module RequestForgeryProtectionTests
     end
   end
 
+  def test_should_raise_for_post_with_null_origin
+    forgery_protection_origin_check do
+      session[:_csrf_token] = @token
+      @controller.stub :form_authenticity_token, @token do
+        exception = assert_raises(ActionController::InvalidAuthenticityToken) do
+          @request.set_header "HTTP_ORIGIN", "null"
+          post :index, params: { custom_authenticity_token: @token }
+        end
+        assert_match "The browser returned a 'null' origin for a request", exception.message
+      end
+    end
+  end
+
   def test_should_block_post_with_origin_checking_and_wrong_origin
+    old_logger = ActionController::Base.logger
+    logger = ActiveSupport::LogSubscriber::TestHelper::MockLogger.new
+    ActionController::Base.logger = logger
+
     forgery_protection_origin_check do
       session[:_csrf_token] = @token
       @controller.stub :form_authenticity_token, @token do
         assert_blocked do
-          @request.set_header 'HTTP_ORIGIN', 'http://bad.host'
+          @request.set_header "HTTP_ORIGIN", "http://bad.host"
           post :index, params: { custom_authenticity_token: @token }
         end
       end
     end
+
+    assert_match(
+      "HTTP Origin header (http://bad.host) didn't match request.base_url (http://test.host)",
+      logger.logged(:warn).last
+    )
+  ensure
+    ActionController::Base.logger = old_logger
   end
 
   def test_should_warn_on_missing_csrf_token
@@ -393,16 +515,16 @@ module RequestForgeryProtectionTests
 
   def test_should_only_allow_same_origin_js_get_with_xhr_header
     assert_cross_origin_blocked { get :same_origin_js }
-    assert_cross_origin_blocked { get :same_origin_js, format: 'js' }
+    assert_cross_origin_blocked { get :same_origin_js, format: "js" }
     assert_cross_origin_blocked do
-      @request.accept = 'text/javascript'
+      @request.accept = "text/javascript"
       get :negotiate_same_origin
     end
 
     assert_cross_origin_not_blocked { get :same_origin_js, xhr: true }
-    assert_cross_origin_not_blocked { get :same_origin_js, xhr: true, format: 'js'}
+    assert_cross_origin_not_blocked { get :same_origin_js, xhr: true, format: "js" }
     assert_cross_origin_not_blocked do
-      @request.accept = 'text/javascript'
+      @request.accept = "text/javascript"
       get :negotiate_same_origin, xhr: true
     end
   end
@@ -442,32 +564,32 @@ module RequestForgeryProtectionTests
   def test_should_allow_non_get_js_without_xhr_header
     session[:_csrf_token] = @token
     assert_cross_origin_not_blocked { post :same_origin_js, params: { custom_authenticity_token: @token } }
-    assert_cross_origin_not_blocked { post :same_origin_js, params: { format: 'js', custom_authenticity_token: @token } }
+    assert_cross_origin_not_blocked { post :same_origin_js, params: { format: "js", custom_authenticity_token: @token } }
     assert_cross_origin_not_blocked do
-      @request.accept = 'text/javascript'
-      post :negotiate_same_origin, params: { custom_authenticity_token: @token}
+      @request.accept = "text/javascript"
+      post :negotiate_same_origin, params: { custom_authenticity_token: @token }
     end
   end
 
   def test_should_only_allow_cross_origin_js_get_without_xhr_header_if_protection_disabled
     assert_cross_origin_not_blocked { get :cross_origin_js }
-    assert_cross_origin_not_blocked { get :cross_origin_js, format: 'js' }
+    assert_cross_origin_not_blocked { get :cross_origin_js, format: "js" }
     assert_cross_origin_not_blocked do
-      @request.accept = 'text/javascript'
+      @request.accept = "text/javascript"
       get :negotiate_cross_origin
     end
 
     assert_cross_origin_not_blocked { get :cross_origin_js, xhr: true }
-    assert_cross_origin_not_blocked { get :cross_origin_js, xhr: true, format: 'js' }
+    assert_cross_origin_not_blocked { get :cross_origin_js, xhr: true, format: "js" }
     assert_cross_origin_not_blocked do
-      @request.accept = 'text/javascript'
+      @request.accept = "text/javascript"
       get :negotiate_cross_origin, xhr: true
     end
   end
 
   def test_should_not_raise_error_if_token_is_not_a_string
     assert_blocked do
-      patch :index, params: { custom_authenticity_token: { foo: 'bar' } }
+      patch :index, params: { custom_authenticity_token: { foo: "bar" } }
     end
   end
 
@@ -509,20 +631,11 @@ end
 class RequestForgeryProtectionControllerUsingResetSessionTest < ActionController::TestCase
   include RequestForgeryProtectionTests
 
-  setup do
-    @old_request_forgery_protection_token = ActionController::Base.request_forgery_protection_token
-    ActionController::Base.request_forgery_protection_token = :custom_authenticity_token
-  end
-
-  teardown do
-    ActionController::Base.request_forgery_protection_token = @old_request_forgery_protection_token
-  end
-
-  test 'should emit a csrf-param meta tag and a csrf-token meta tag' do
-    @controller.stub :form_authenticity_token, @token + '<=?' do
+  test "should emit a csrf-param meta tag and a csrf-token meta tag" do
+    @controller.stub :form_authenticity_token, @token + "<=?" do
       get :meta
-      assert_select 'meta[name=?][content=?]', 'csrf-param', 'custom_authenticity_token'
-      assert_select 'meta[name=?]', 'csrf-token'
+      assert_select "meta[name=?][content=?]", "csrf-param", "custom_authenticity_token"
+      assert_select "meta[name=?]", "csrf-token"
       regexp = "#{@token}&lt;=\?"
       assert_match(/#{regexp}/, @response.body)
     end
@@ -531,26 +644,27 @@ end
 
 class RequestForgeryProtectionControllerUsingNullSessionTest < ActionController::TestCase
   class NullSessionDummyKeyGenerator
-    def generate_key(secret)
-      '03312270731a2ed0d11ed091c2338a06'
+    def generate_key(secret, length = nil)
+      "03312270731a2ed0d11ed091c2338a06"
     end
   end
 
   def setup
     @request.env[ActionDispatch::Cookies::GENERATOR_KEY] = NullSessionDummyKeyGenerator.new
+    @request.env[ActionDispatch::Cookies::COOKIES_ROTATIONS] = ActiveSupport::Messages::RotationConfiguration.new
   end
 
-  test 'should allow to set signed cookies' do
+  test "should allow to set signed cookies" do
     post :signed
     assert_response :ok
   end
 
-  test 'should allow to set encrypted cookies' do
+  test "should allow to set encrypted cookies" do
     post :encrypted
     assert_response :ok
   end
 
-  test 'should allow reset_session' do
+  test "should allow reset_session" do
     post :try_to_reset_session
     assert_response :ok
   end
@@ -610,26 +724,26 @@ class FreeCookieControllerTest < ActionController::TestCase
   def test_should_not_render_form_with_token_tag
     SecureRandom.stub :base64, @token do
       get :index
-      assert_select 'form>div>input[name=?][value=?]', 'authenticity_token', @token, false
+      assert_select "form>div>input[name=?][value=?]", "authenticity_token", @token, false
     end
   end
 
   def test_should_not_render_button_to_with_token_tag
     SecureRandom.stub :base64, @token do
       get :show_button
-      assert_select 'form>div>input[name=?][value=?]', 'authenticity_token', @token, false
+      assert_select "form>div>input[name=?][value=?]", "authenticity_token", @token, false
     end
   end
 
   def test_should_allow_all_methods_without_token
     SecureRandom.stub :base64, @token do
       [:post, :patch, :put, :delete].each do |method|
-        assert_nothing_raised { send(method, :index)}
+        assert_nothing_raised { send(method, :index) }
       end
     end
   end
 
-  test 'should not emit a csrf-token meta tag' do
+  test "should not emit a csrf-token meta tag" do
     SecureRandom.stub :base64, @token do
       get :meta
       assert @response.body.blank?
@@ -656,7 +770,7 @@ class CustomAuthenticityParamControllerTest < ActionController::TestCase
     ActionController::Base.logger = @logger
     begin
       @controller.stub :valid_authenticity_token?, :true do
-        post :index, params: { custom_token_name: 'foobar' }
+        post :index, params: { custom_token_name: "foobar" }
         assert_equal 0, @logger.logged(:warn).size
       end
     ensure
@@ -668,7 +782,7 @@ class CustomAuthenticityParamControllerTest < ActionController::TestCase
     ActionController::Base.logger = @logger
 
     begin
-      post :index, params: { custom_token_name: 'bazqux' }
+      post :index, params: { custom_token_name: "bazqux" }
       assert_equal 1, @logger.logged(:warn).size
     ensure
       ActionController::Base.logger = @old_logger
@@ -677,10 +791,19 @@ class CustomAuthenticityParamControllerTest < ActionController::TestCase
 end
 
 class PerFormTokensControllerTest < ActionController::TestCase
+  def setup
+    @old_request_forgery_protection_token = ActionController::Base.request_forgery_protection_token
+    ActionController::Base.request_forgery_protection_token = :custom_authenticity_token
+  end
+
+  def teardown
+    ActionController::Base.request_forgery_protection_token = @old_request_forgery_protection_token
+  end
+
   def test_per_form_token_is_same_size_as_global_token
     get :index
     expected = ActionController::RequestForgeryProtection::AUTHENTICITY_TOKEN_LENGTH
-    actual = @controller.send(:per_form_csrf_token, session, '/path', 'post').size
+    actual = @controller.send(:per_form_csrf_token, session, "/path", "post").size
     assert_equal expected, actual
   end
 
@@ -692,9 +815,9 @@ class PerFormTokensControllerTest < ActionController::TestCase
     assert_matches_session_token_on_server form_token
 
     # This is required because PATH_INFO isn't reset between requests.
-    @request.env['PATH_INFO'] = '/per_form_tokens/post_one'
+    @request.env["PATH_INFO"] = "/per_form_tokens/post_one"
     assert_nothing_raised do
-      post :post_one, params: {custom_authenticity_token: form_token}
+      post :post_one, params: { custom_authenticity_token: form_token }
     end
     assert_response :success
   end
@@ -707,9 +830,9 @@ class PerFormTokensControllerTest < ActionController::TestCase
     assert_matches_session_token_on_server form_token
 
     # This is required because PATH_INFO isn't reset between requests.
-    @request.env['PATH_INFO'] = '/per_form_tokens/post_two'
+    @request.env["PATH_INFO"] = "/per_form_tokens/post_two"
     assert_raises(ActionController::InvalidAuthenticityToken) do
-      post :post_two, params: {custom_authenticity_token: form_token}
+      post :post_two, params: { custom_authenticity_token: form_token }
     end
   end
 
@@ -721,21 +844,21 @@ class PerFormTokensControllerTest < ActionController::TestCase
     assert_matches_session_token_on_server form_token
 
     # This is required because PATH_INFO isn't reset between requests.
-    @request.env['PATH_INFO'] = '/per_form_tokens/post_one'
+    @request.env["PATH_INFO"] = "/per_form_tokens/post_one"
     assert_raises(ActionController::InvalidAuthenticityToken) do
-      patch :post_one, params: {custom_authenticity_token: form_token}
+      patch :post_one, params: { custom_authenticity_token: form_token }
     end
   end
 
   def test_rejects_token_for_incorrect_method_button_to
-    get :button_to, params: { form_method: 'delete' }
+    get :button_to, params: { form_method: "delete" }
 
     form_token = assert_presence_and_fetch_form_csrf_token
 
-    assert_matches_session_token_on_server form_token, 'delete'
+    assert_matches_session_token_on_server form_token, "delete"
 
     # This is required because PATH_INFO isn't reset between requests.
-    @request.env['PATH_INFO'] = '/per_form_tokens/post_one'
+    @request.env["PATH_INFO"] = "/per_form_tokens/post_one"
     assert_raises(ActionController::InvalidAuthenticityToken) do
       patch :post_one, params: { custom_authenticity_token: form_token }
     end
@@ -746,10 +869,10 @@ class PerFormTokensControllerTest < ActionController::TestCase
 
     form_token = assert_presence_and_fetch_form_csrf_token
 
-    assert_matches_session_token_on_server form_token, 'post'
+    assert_matches_session_token_on_server form_token, "post"
 
     # This is required because PATH_INFO isn't reset between requests.
-    @request.env['PATH_INFO'] = '/per_form_tokens/post_one'
+    @request.env["PATH_INFO"] = "/per_form_tokens/post_one"
     assert_nothing_raised do
       post :post_one, params: { custom_authenticity_token: form_token }
     end
@@ -764,7 +887,7 @@ class PerFormTokensControllerTest < ActionController::TestCase
       assert_matches_session_token_on_server form_token, verb
 
       # This is required because PATH_INFO isn't reset between requests.
-      @request.env['PATH_INFO'] = '/per_form_tokens/post_one'
+      @request.env["PATH_INFO"] = "/per_form_tokens/post_one"
       assert_nothing_raised do
         send verb, :post_one, params: { custom_authenticity_token: form_token }
       end
@@ -777,50 +900,50 @@ class PerFormTokensControllerTest < ActionController::TestCase
     token = @controller.send(:form_authenticity_token)
 
     # This is required because PATH_INFO isn't reset between requests.
-    @request.env['PATH_INFO'] = '/per_form_tokens/post_one'
+    @request.env["PATH_INFO"] = "/per_form_tokens/post_one"
     assert_nothing_raised do
-      post :post_one, params: {custom_authenticity_token: token}
+      post :post_one, params: { custom_authenticity_token: token }
     end
     assert_response :success
   end
 
   def test_ignores_params
-    get :index, params: {form_path: '/per_form_tokens/post_one?foo=bar'}
+    get :index, params: { form_path: "/per_form_tokens/post_one?foo=bar" }
 
     form_token = assert_presence_and_fetch_form_csrf_token
 
     assert_matches_session_token_on_server form_token
 
     # This is required because PATH_INFO isn't reset between requests.
-    @request.env['PATH_INFO'] = '/per_form_tokens/post_one?foo=baz'
+    @request.env["PATH_INFO"] = "/per_form_tokens/post_one?foo=baz"
     assert_nothing_raised do
-      post :post_one, params: {custom_authenticity_token: form_token, baz: 'foo'}
+      post :post_one, params: { custom_authenticity_token: form_token, baz: "foo" }
     end
     assert_response :success
   end
 
   def test_ignores_trailing_slash_during_generation
-    get :index, params: {form_path: '/per_form_tokens/post_one/'}
+    get :index, params: { form_path: "/per_form_tokens/post_one/" }
 
     form_token = assert_presence_and_fetch_form_csrf_token
 
     # This is required because PATH_INFO isn't reset between requests.
-    @request.env['PATH_INFO'] = '/per_form_tokens/post_one'
+    @request.env["PATH_INFO"] = "/per_form_tokens/post_one"
     assert_nothing_raised do
-      post :post_one, params: {custom_authenticity_token: form_token}
+      post :post_one, params: { custom_authenticity_token: form_token }
     end
     assert_response :success
   end
 
   def test_ignores_origin_during_generation
-    get :index, params: {form_path: 'https://example.com/per_form_tokens/post_one/'}
+    get :index, params: { form_path: "https://example.com/per_form_tokens/post_one/" }
 
     form_token = assert_presence_and_fetch_form_csrf_token
 
     # This is required because PATH_INFO isn't reset between requests.
-    @request.env['PATH_INFO'] = '/per_form_tokens/post_one'
+    @request.env["PATH_INFO"] = "/per_form_tokens/post_one"
     assert_nothing_raised do
-      post :post_one, params: {custom_authenticity_token: form_token}
+      post :post_one, params: { custom_authenticity_token: form_token }
     end
     assert_response :success
   end
@@ -831,21 +954,21 @@ class PerFormTokensControllerTest < ActionController::TestCase
     form_token = assert_presence_and_fetch_form_csrf_token
 
     # This is required because PATH_INFO isn't reset between requests.
-    @request.env['PATH_INFO'] = '/per_form_tokens/post_one/'
+    @request.env["PATH_INFO"] = "/per_form_tokens/post_one/"
     assert_nothing_raised do
-      post :post_one, params: {custom_authenticity_token: form_token}
+      post :post_one, params: { custom_authenticity_token: form_token }
     end
     assert_response :success
   end
 
   def test_method_is_case_insensitive
-    get :index, params: {form_method: "POST"}
+    get :index, params: { form_method: "POST" }
 
     form_token = assert_presence_and_fetch_form_csrf_token
     # This is required because PATH_INFO isn't reset between requests.
-    @request.env['PATH_INFO'] = '/per_form_tokens/post_one/'
+    @request.env["PATH_INFO"] = "/per_form_tokens/post_one/"
     assert_nothing_raised do
-      post :post_one, params: {custom_authenticity_token: form_token}
+      post :post_one, params: { custom_authenticity_token: form_token }
     end
     assert_response :success
   end
@@ -853,15 +976,38 @@ class PerFormTokensControllerTest < ActionController::TestCase
   private
     def assert_presence_and_fetch_form_csrf_token
       assert_select 'input[name="custom_authenticity_token"]' do |input|
-        form_csrf_token = input.first['value']
+        form_csrf_token = input.first["value"]
         assert_not_nil form_csrf_token
         return form_csrf_token
       end
     end
 
-    def assert_matches_session_token_on_server(form_token, method = 'post')
+    def assert_matches_session_token_on_server(form_token, method = "post")
       actual = @controller.send(:unmask_token, Base64.strict_decode64(form_token))
-      expected = @controller.send(:per_form_csrf_token, session, '/per_form_tokens/post_one', method)
+      expected = @controller.send(:per_form_csrf_token, session, "/per_form_tokens/post_one", method)
       assert_equal expected, actual
     end
 end
+
+class SkipProtectionControllerTest < ActionController::TestCase
+  def test_should_not_allow_post_without_token_when_not_skipping
+    @controller.skip_requested = false
+    assert_blocked { post :index }
+  end
+
+  def test_should_allow_post_without_token_when_skipping
+    @controller.skip_requested = true
+    assert_not_blocked { post :index }
+  end
+
+  def assert_blocked
+    assert_raises(ActionController::InvalidAuthenticityToken) do
+      yield
+    end
+  end
+
+  def assert_not_blocked
+    assert_nothing_raised { yield }
+    assert_response :success
+  end
+end
diff --git a/actionpack/test/controller/required_params_test.rb b/actionpack/test/controller/required_params_test.rb
index b6efcd6f9a..4a83d07e7d 100644
--- a/actionpack/test/controller/required_params_test.rb
+++ b/actionpack/test/controller/required_params_test.rb
@@ -1,4 +1,6 @@
-require 'abstract_unit'
+# frozen_string_literal: true
+
+require "abstract_unit"
 
 class BooksController < ActionController::Base
   def create
@@ -32,7 +34,6 @@ class ActionControllerRequiredParamsTest < ActionController::TestCase
 end
 
 class ParametersRequireTest < ActiveSupport::TestCase
-
   test "required parameters should accept and return false value" do
     assert_equal(false, ActionController::Parameters.new(person: false).require(:person))
   end
@@ -50,17 +51,17 @@ class ParametersRequireTest < ActiveSupport::TestCase
   end
 
   test "require array when all required params are present" do
-    safe_params = ActionController::Parameters.new(person: {first_name: 'Gaurish', title: 'Mjallo', city: 'Barcelona'})
+    safe_params = ActionController::Parameters.new(person: { first_name: "Gaurish", title: "Mjallo", city: "Barcelona" })
       .require(:person)
       .require([:first_name, :title])
 
     assert_kind_of Array, safe_params
-    assert_equal ['Gaurish', 'Mjallo'], safe_params
+    assert_equal ["Gaurish", "Mjallo"], safe_params
   end
 
   test "require array when a required param is missing" do
     assert_raises(ActionController::ParameterMissing) do
-      ActionController::Parameters.new(person: {first_name: 'Gaurish', title: nil})
+      ActionController::Parameters.new(person: { first_name: "Gaurish", title: nil })
         .require(:person)
         .require([:first_name, :title])
     end
@@ -73,9 +74,27 @@ class ParametersRequireTest < ActiveSupport::TestCase
     assert params.value?("cinco")
   end
 
-  test "Deprecated methods are deprecated" do
-    assert_deprecated do
-      ActionController::Parameters.new(foo: "bar").merge!({bar: "foo"})
+  test "to_param works like in a Hash" do
+    params = ActionController::Parameters.new(nested: { key: "value" }).permit!
+    assert_equal({ nested: { key: "value" } }.to_param, params.to_param)
+
+    params = { root: ActionController::Parameters.new(nested: { key: "value" }).permit! }
+    assert_equal({ root: { nested: { key: "value" } } }.to_param, params.to_param)
+
+    assert_raise(ActionController::UnfilteredParameters) do
+      ActionController::Parameters.new(nested: { key: "value" }).to_param
+    end
+  end
+
+  test "to_query works like in a Hash" do
+    params = ActionController::Parameters.new(nested: { key: "value" }).permit!
+    assert_equal({ nested: { key: "value" } }.to_query, params.to_query)
+
+    params = { root: ActionController::Parameters.new(nested: { key: "value" }).permit! }
+    assert_equal({ root: { nested: { key: "value" } } }.to_query, params.to_query)
+
+    assert_raise(ActionController::UnfilteredParameters) do
+      ActionController::Parameters.new(nested: { key: "value" }).to_query
     end
   end
 end
diff --git a/actionpack/test/controller/rescue_test.rb b/actionpack/test/controller/rescue_test.rb
index c088e5a043..4ed79073e5 100644
--- a/actionpack/test/controller/rescue_test.rb
+++ b/actionpack/test/controller/rescue_test.rb
@@ -1,4 +1,6 @@
-require 'abstract_unit'
+# frozen_string_literal: true
+
+require "abstract_unit"
 
 class RescueController < ActionController::Base
   class NotAuthorized < StandardError
@@ -31,50 +33,50 @@ class RescueController < ActionController::Base
   class ResourceUnavailableToRescueAsString < StandardError
   end
 
-  # We use a fully-qualified name in some strings, and a relative constant
+  # We use a fully qualified name in some strings, and a relative constant
   # name in some other to test correct handling of both cases.
 
-  rescue_from NotAuthorized, :with => :deny_access
-  rescue_from 'RescueController::NotAuthorizedToRescueAsString', :with => :deny_access
+  rescue_from NotAuthorized, with: :deny_access
+  rescue_from "RescueController::NotAuthorizedToRescueAsString", with: :deny_access
 
-  rescue_from RecordInvalid, :with => :show_errors
-  rescue_from 'RescueController::RecordInvalidToRescueAsString', :with => :show_errors
+  rescue_from RecordInvalid, with: :show_errors
+  rescue_from "RescueController::RecordInvalidToRescueAsString", with: :show_errors
 
-  rescue_from NotAllowed, :with => proc { head :forbidden }
-  rescue_from 'RescueController::NotAllowedToRescueAsString', :with => proc { head :forbidden }
+  rescue_from NotAllowed, with: proc { head :forbidden }
+  rescue_from "RescueController::NotAllowedToRescueAsString", with: proc { head :forbidden }
 
   rescue_from InvalidRequest, with: proc { |exception| render plain: exception.message }
-  rescue_from 'InvalidRequestToRescueAsString', with: proc { |exception| render plain: exception.message }
+  rescue_from "InvalidRequestToRescueAsString", with: proc { |exception| render plain: exception.message }
 
   rescue_from BadGateway do
     head 502
   end
-  rescue_from 'BadGatewayToRescueAsString' do
+  rescue_from "BadGatewayToRescueAsString" do
     head 502
   end
 
   rescue_from ResourceUnavailable do |exception|
     render plain: exception.message
   end
-  rescue_from 'ResourceUnavailableToRescueAsString' do |exception|
+  rescue_from "ResourceUnavailableToRescueAsString" do |exception|
     render plain: exception.message
   end
 
   rescue_from ActionView::TemplateError do
-    render plain: 'action_view templater error'
+    render plain: "action_view templater error"
   end
 
   rescue_from IOError do
-    render plain: 'io error'
+    render plain: "io error"
   end
 
-  before_action(only: :before_action_raises) { raise 'umm nice' }
+  before_action(only: :before_action_raises) { raise "umm nice" }
 
   def before_action_raises
   end
 
   def raises
-    render plain: 'already rendered'
+    render plain: "already rendered"
     raise "don't panic!"
   end
 
@@ -149,7 +151,7 @@ class RescueController < ActionController::Base
     raise RangeError
   end
 
-  protected
+  private
     def deny_access
       head :forbidden
     end
@@ -160,7 +162,6 @@ class RescueController < ActionController::Base
 end
 
 class ExceptionInheritanceRescueController < ActionController::Base
-
   class ParentException < StandardError
   end
 
@@ -170,9 +171,9 @@ class ExceptionInheritanceRescueController < ActionController::Base
   class GrandchildException < ChildException
   end
 
-  rescue_from ChildException,      :with => lambda { head :ok }
-  rescue_from ParentException,     :with => lambda { head :created }
-  rescue_from GrandchildException, :with => lambda { head :no_content }
+  rescue_from ChildException,      with: lambda { head :ok }
+  rescue_from ParentException,     with: lambda { head :created }
+  rescue_from GrandchildException, with: lambda { head :no_content }
 
   def raise_parent_exception
     raise ParentException
@@ -206,7 +207,7 @@ class ControllerInheritanceRescueController < ExceptionInheritanceRescueControll
   class SecondExceptionInChildController < StandardError
   end
 
-  rescue_from FirstExceptionInChildController, 'SecondExceptionInChildController', :with => lambda { head :gone }
+  rescue_from FirstExceptionInChildController, "SecondExceptionInChildController", with: lambda { head :gone }
 
   def raise_first_exception_in_child_controller
     raise FirstExceptionInChildController
@@ -291,17 +292,17 @@ class RescueControllerTest < ActionController::TestCase
     assert_equal "RescueController::ResourceUnavailableToRescueAsString", @response.body
   end
 
-  test 'rescue when wrapper has more specific handler than cause' do
+  test "rescue when wrapper has more specific handler than cause" do
     get :exception_with_more_specific_handler_for_wrapper
     assert_response :forbidden
   end
 
-  test 'rescue when cause has more specific handler than wrapper' do
+  test "rescue when cause has more specific handler than wrapper" do
     get :exception_with_more_specific_handler_for_cause
     assert_response :unprocessable_entity
   end
 
-  test 'rescue when cause has handler, but wrapper doesnt' do
+  test "rescue when cause has handler, but wrapper doesnt" do
     get :exception_with_no_handler_for_wrapper
     assert_response :unprocessable_entity
   end
@@ -311,10 +312,10 @@ class RescueTest < ActionDispatch::IntegrationTest
   class TestController < ActionController::Base
     class RecordInvalid < StandardError
       def message
-        'invalid'
+        "invalid"
       end
     end
-    rescue_from RecordInvalid, :with => :show_errors
+    rescue_from RecordInvalid, with: :show_errors
 
     def foo
       render plain: "foo"
@@ -325,26 +326,26 @@ class RescueTest < ActionDispatch::IntegrationTest
     end
 
     def b00m
-      raise 'b00m'
+      raise "b00m"
     end
 
-    protected
+    private
       def show_errors(exception)
         render plain: exception.message
       end
   end
 
-  test 'normal request' do
+  test "normal request" do
     with_test_routing do
-      get '/foo'
-      assert_equal 'foo', response.body
+      get "/foo"
+      assert_equal "foo", response.body
     end
   end
 
-  test 'rescue exceptions inside controller' do
+  test "rescue exceptions inside controller" do
     with_test_routing do
-      get '/invalid'
-      assert_equal 'invalid', response.body
+      get "/invalid"
+      assert_equal "invalid", response.body
     end
   end
 
@@ -353,9 +354,9 @@ class RescueTest < ActionDispatch::IntegrationTest
     def with_test_routing
       with_routing do |set|
         set.draw do
-          get 'foo', :to => ::RescueTest::TestController.action(:foo)
-          get 'invalid', :to => ::RescueTest::TestController.action(:invalid)
-          get 'b00m', :to => ::RescueTest::TestController.action(:b00m)
+          get "foo", to: ::RescueTest::TestController.action(:foo)
+          get "invalid", to: ::RescueTest::TestController.action(:invalid)
+          get "b00m", to: ::RescueTest::TestController.action(:b00m)
         end
         yield
       end
diff --git a/actionpack/test/controller/resources_test.rb b/actionpack/test/controller/resources_test.rb
index 8e38af5025..30bea64c55 100644
--- a/actionpack/test/controller/resources_test.rb
+++ b/actionpack/test/controller/resources_test.rb
@@ -1,7 +1,9 @@
-require 'abstract_unit'
-require 'active_support/core_ext/object/try'
-require 'active_support/core_ext/object/with_options'
-require 'active_support/core_ext/array/extract_options'
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "active_support/core_ext/object/try"
+require "active_support/core_ext/object/with_options"
+require "active_support/core_ext/array/extract_options"
 
 class AdminController < ResourcesController; end
 class MessagesController < ResourcesController; end
@@ -26,43 +28,43 @@ class ResourcesTest < ActionController::TestCase
   end
 
   def test_override_paths_for_member_and_collection_methods
-    collection_methods = { :rss => :get, :reorder => :post, :csv => :post }
-    member_methods    = { :rss => :get, :atom => :get, :upload => :post, :fix => :post }
-    path_names = {:new => 'nuevo', :rss => 'canal', :fix => 'corrigir' }
+    collection_methods = { rss: :get, reorder: :post, csv: :post }
+    member_methods = { rss: :get, atom: :get, upload: :post, fix: :post }
+    path_names = { new: "nuevo", rss: "canal", fix: "corrigir" }
 
     with_restful_routing :messages,
-        :collection => collection_methods,
-        :member => member_methods,
-        :path_names => path_names do
+        collection: collection_methods,
+        member: member_methods,
+        path_names: path_names do
 
       assert_restful_routes_for :messages,
-          :collection => collection_methods,
-          :member => member_methods,
-          :path_names => path_names do |options|
+          collection: collection_methods,
+          member: member_methods,
+          path_names: path_names do |options|
         member_methods.each do |action, method|
-          assert_recognizes(options.merge(:action => action.to_s, :id => '1'),
-            :path => "/messages/1/#{path_names[action] || action}",
-            :method => method)
+          assert_recognizes(options.merge(action: action.to_s, id: "1"),
+            path: "/messages/1/#{path_names[action] || action}",
+            method: method)
         end
 
         collection_methods.each do |action, method|
-          assert_recognizes(options.merge(:action => action.to_s),
-            :path => "/messages/#{path_names[action] || action}",
-            :method => method)
+          assert_recognizes(options.merge(action: action.to_s),
+            path: "/messages/#{path_names[action] || action}",
+            method: method)
         end
       end
 
       assert_restful_named_routes_for :messages,
-          :collection => collection_methods,
-          :member => member_methods,
-          :path_names => path_names do |options|
+          collection: collection_methods,
+          member: member_methods,
+          path_names: path_names do |options|
 
         collection_methods.each_key do |action|
-          assert_named_route "/messages/#{path_names[action] || action}", "#{action}_messages_path", :action => action
+          assert_named_route "/messages/#{path_names[action] || action}", "#{action}_messages_path", action: action
         end
 
         member_methods.each_key do |action|
-          assert_named_route "/messages/1/#{path_names[action] || action}", "#{action}_message_path", :action => action, :id => "1"
+          assert_named_route "/messages/1/#{path_names[action] || action}", "#{action}_message_path", action: action, id: "1"
         end
 
       end
@@ -77,182 +79,182 @@ class ResourcesTest < ActionController::TestCase
   end
 
   def test_multiple_resources_with_options
-    expected_options = {:controller => 'threads', :action => 'index'}
+    expected_options = { controller: "threads", action: "index" }
 
     with_restful_routing :messages, :comments, expected_options.slice(:controller) do
-      assert_recognizes(expected_options, :path => 'comments')
-      assert_recognizes(expected_options, :path => 'messages')
+      assert_recognizes(expected_options, path: "comments")
+      assert_recognizes(expected_options, path: "messages")
     end
   end
 
   def test_with_custom_conditions
-    with_restful_routing :messages, :conditions => { :subdomain => 'app' } do
-      assert @routes.recognize_path("/messages", :method => :get, :subdomain => 'app')
+    with_restful_routing :messages, conditions: { subdomain: "app" } do
+      assert @routes.recognize_path("/messages", method: :get, subdomain: "app")
     end
   end
 
   def test_irregular_id_with_no_constraints_should_raise_error
-    expected_options = {:controller => 'messages', :action => 'show', :id => '1.1.1'}
+    expected_options = { controller: "messages", action: "show", id: "1.1.1" }
 
     with_restful_routing :messages do
       assert_raise(Assertion) do
-        assert_recognizes(expected_options, :path => 'messages/1.1.1', :method => :get)
+        assert_recognizes(expected_options, path: "messages/1.1.1", method: :get)
       end
     end
   end
 
   def test_irregular_id_with_constraints_should_pass
-    expected_options = {:controller => 'messages', :action => 'show', :id => '1.1.1'}
+    expected_options = { controller: "messages", action: "show", id: "1.1.1" }
 
-    with_restful_routing(:messages, :constraints => {:id => /[0-9]\.[0-9]\.[0-9]/}) do
-      assert_recognizes(expected_options, :path => 'messages/1.1.1', :method => :get)
+    with_restful_routing(:messages, constraints: { id: /[0-9]\.[0-9]\.[0-9]/ }) do
+      assert_recognizes(expected_options, path: "messages/1.1.1", method: :get)
     end
   end
 
   def test_with_path_prefix_constraints
-    expected_options = {:controller => 'messages', :action => 'show', :thread_id => '1.1.1', :id => '1'}
-    with_restful_routing :messages, :path_prefix => '/thread/:thread_id', :constraints => {:thread_id => /[0-9]\.[0-9]\.[0-9]/} do
-      assert_recognizes(expected_options, :path => 'thread/1.1.1/messages/1', :method => :get)
+    expected_options = { controller: "messages", action: "show", thread_id: "1.1.1", id: "1" }
+    with_restful_routing :messages, path_prefix: "/thread/:thread_id", constraints: { thread_id: /[0-9]\.[0-9]\.[0-9]/ } do
+      assert_recognizes(expected_options, path: "thread/1.1.1/messages/1", method: :get)
     end
   end
 
   def test_irregular_id_constraints_should_get_passed_to_member_actions
-    expected_options = {:controller => 'messages', :action => 'custom', :id => '1.1.1'}
+    expected_options = { controller: "messages", action: "custom", id: "1.1.1" }
 
-    with_restful_routing(:messages, :member => {:custom => :get}, :constraints => {:id => /[0-9]\.[0-9]\.[0-9]/}) do
-      assert_recognizes(expected_options, :path => 'messages/1.1.1/custom', :method => :get)
+    with_restful_routing(:messages, member: { custom: :get }, constraints: { id: /[0-9]\.[0-9]\.[0-9]/ }) do
+      assert_recognizes(expected_options, path: "messages/1.1.1/custom", method: :get)
     end
   end
 
   def test_with_path_prefix
-    with_restful_routing :messages, :path_prefix => '/thread/:thread_id' do
-      assert_simply_restful_for :messages, :path_prefix => 'thread/5/', :options => { :thread_id => '5' }
+    with_restful_routing :messages, path_prefix: "/thread/:thread_id" do
+      assert_simply_restful_for :messages, path_prefix: "thread/5/", options: { thread_id: "5" }
     end
   end
 
   def test_multiple_with_path_prefix
-    with_restful_routing :messages, :comments, :path_prefix => '/thread/:thread_id' do
-      assert_simply_restful_for :messages, :path_prefix => 'thread/5/', :options => { :thread_id => '5' }
-      assert_simply_restful_for :comments, :path_prefix => 'thread/5/', :options => { :thread_id => '5' }
+    with_restful_routing :messages, :comments, path_prefix: "/thread/:thread_id" do
+      assert_simply_restful_for :messages, path_prefix: "thread/5/", options: { thread_id: "5" }
+      assert_simply_restful_for :comments, path_prefix: "thread/5/", options: { thread_id: "5" }
     end
   end
 
   def test_with_name_prefix
-    with_restful_routing :messages, :as => 'post_messages' do
-      assert_simply_restful_for :messages, :name_prefix => 'post_'
+    with_restful_routing :messages, as: "post_messages" do
+      assert_simply_restful_for :messages, name_prefix: "post_"
     end
   end
 
   def test_with_collection_actions
-    actions = { 'a' => :get, 'b' => :put, 'c' => :post, 'd' => :delete, 'e' => :patch }
+    actions = { "a" => :get, "b" => :put, "c" => :post, "d" => :delete, "e" => :patch }
 
     with_routing do |set|
       set.draw do
         resources :messages do
-          get    :a, :on => :collection
-          put    :b, :on => :collection
-          post   :c, :on => :collection
-          delete :d, :on => :collection
-          patch  :e, :on => :collection
+          get    :a, on: :collection
+          put    :b, on: :collection
+          post   :c, on: :collection
+          delete :d, on: :collection
+          patch  :e, on: :collection
         end
       end
 
       assert_restful_routes_for :messages do |options|
         actions.each do |action, method|
-          assert_recognizes(options.merge(:action => action), :path => "/messages/#{action}", :method => method)
+          assert_recognizes(options.merge(action: action), path: "/messages/#{action}", method: method)
         end
       end
 
       assert_restful_named_routes_for :messages do
         actions.each_key do |action|
-          assert_named_route "/messages/#{action}", "#{action}_messages_path", :action => action
+          assert_named_route "/messages/#{action}", "#{action}_messages_path", action: action
         end
       end
     end
   end
 
   def test_with_collection_actions_and_name_prefix
-    actions = { 'a' => :get, 'b' => :put, 'c' => :post, 'd' => :delete, 'e' => :patch }
+    actions = { "a" => :get, "b" => :put, "c" => :post, "d" => :delete, "e" => :patch }
 
     with_routing do |set|
       set.draw do
-        scope '/threads/:thread_id' do
-          resources :messages, :as => 'thread_messages' do
-            get    :a, :on => :collection
-            put    :b, :on => :collection
-            post   :c, :on => :collection
-            delete :d, :on => :collection
-            patch  :e, :on => :collection
+        scope "/threads/:thread_id" do
+          resources :messages, as: "thread_messages" do
+            get    :a, on: :collection
+            put    :b, on: :collection
+            post   :c, on: :collection
+            delete :d, on: :collection
+            patch  :e, on: :collection
           end
         end
       end
 
-      assert_restful_routes_for :messages, :path_prefix => 'threads/1/', :name_prefix => 'thread_', :options => { :thread_id => '1' } do |options|
+      assert_restful_routes_for :messages, path_prefix: "threads/1/", name_prefix: "thread_", options: { thread_id: "1" } do |options|
         actions.each do |action, method|
-          assert_recognizes(options.merge(:action => action), :path => "/threads/1/messages/#{action}", :method => method)
+          assert_recognizes(options.merge(action: action), path: "/threads/1/messages/#{action}", method: method)
         end
       end
 
-      assert_restful_named_routes_for :messages, :path_prefix => 'threads/1/', :name_prefix => 'thread_', :options => { :thread_id => '1' } do
+      assert_restful_named_routes_for :messages, path_prefix: "threads/1/", name_prefix: "thread_", options: { thread_id: "1" } do
         actions.each_key do |action|
-          assert_named_route "/threads/1/messages/#{action}", "#{action}_thread_messages_path", :action => action
+          assert_named_route "/threads/1/messages/#{action}", "#{action}_thread_messages_path", action: action
         end
       end
     end
   end
 
   def test_with_collection_actions_and_name_prefix_and_member_action_with_same_name
-    actions = { 'a' => :get }
+    actions = { "a" => :get }
 
     with_routing do |set|
       set.draw do
-        scope '/threads/:thread_id' do
-          resources :messages, :as => 'thread_messages' do
-            get :a, :on => :collection
-            get :a, :on => :member
+        scope "/threads/:thread_id" do
+          resources :messages, as: "thread_messages" do
+            get :a, on: :collection
+            get :a, on: :member
           end
         end
       end
 
-      assert_restful_routes_for :messages, :path_prefix => 'threads/1/', :name_prefix => 'thread_', :options => { :thread_id => '1' } do |options|
+      assert_restful_routes_for :messages, path_prefix: "threads/1/", name_prefix: "thread_", options: { thread_id: "1" } do |options|
         actions.each do |action, method|
-          assert_recognizes(options.merge(:action => action), :path => "/threads/1/messages/#{action}", :method => method)
+          assert_recognizes(options.merge(action: action), path: "/threads/1/messages/#{action}", method: method)
         end
       end
 
-      assert_restful_named_routes_for :messages, :path_prefix => 'threads/1/', :name_prefix => 'thread_', :options => { :thread_id => '1' } do
+      assert_restful_named_routes_for :messages, path_prefix: "threads/1/", name_prefix: "thread_", options: { thread_id: "1" } do
         actions.each_key do |action|
-          assert_named_route "/threads/1/messages/#{action}", "#{action}_thread_messages_path", :action => action
+          assert_named_route "/threads/1/messages/#{action}", "#{action}_thread_messages_path", action: action
         end
       end
     end
   end
 
   def test_with_collection_action_and_name_prefix_and_formatted
-    actions = { 'a' => :get, 'b' => :put, 'c' => :post, 'd' => :delete, 'e' => :patch }
+    actions = { "a" => :get, "b" => :put, "c" => :post, "d" => :delete, "e" => :patch }
 
     with_routing do |set|
       set.draw do
-        scope '/threads/:thread_id' do
-          resources :messages, :as => 'thread_messages' do
-            get    :a, :on => :collection
-            put    :b, :on => :collection
-            post   :c, :on => :collection
-            delete :d, :on => :collection
-            patch  :e, :on => :collection
+        scope "/threads/:thread_id" do
+          resources :messages, as: "thread_messages" do
+            get    :a, on: :collection
+            put    :b, on: :collection
+            post   :c, on: :collection
+            delete :d, on: :collection
+            patch  :e, on: :collection
           end
         end
       end
 
-      assert_restful_routes_for :messages, :path_prefix => 'threads/1/', :name_prefix => 'thread_', :options => { :thread_id => '1' } do |options|
+      assert_restful_routes_for :messages, path_prefix: "threads/1/", name_prefix: "thread_", options: { thread_id: "1" } do |options|
         actions.each do |action, method|
-          assert_recognizes(options.merge(:action => action, :format => 'xml'), :path => "/threads/1/messages/#{action}.xml", :method => method)
+          assert_recognizes(options.merge(action: action, format: "xml"), path: "/threads/1/messages/#{action}.xml", method: method)
         end
       end
 
-      assert_restful_named_routes_for :messages, :path_prefix => 'threads/1/', :name_prefix => 'thread_', :options => { :thread_id => '1' } do
+      assert_restful_named_routes_for :messages, path_prefix: "threads/1/", name_prefix: "thread_", options: { thread_id: "1" } do
         actions.each_key do |action|
-          assert_named_route "/threads/1/messages/#{action}.xml", "#{action}_thread_messages_path", :action => action, :format => 'xml'
+          assert_named_route "/threads/1/messages/#{action}.xml", "#{action}_thread_messages_path", action: action, format: "xml"
         end
       end
     end
@@ -260,11 +262,11 @@ class ResourcesTest < ActionController::TestCase
 
   def test_with_member_action
     [:patch, :put, :post].each do |method|
-      with_restful_routing :messages, :member => { :mark => method } do
-        mark_options = {:action => 'mark', :id => '1'}
+      with_restful_routing :messages, member: { mark: method } do
+        mark_options = { action: "mark", id: "1" }
         mark_path    = "/messages/1/mark"
         assert_restful_routes_for :messages do |options|
-          assert_recognizes(options.merge(mark_options), :path => mark_path, :method => method)
+          assert_recognizes(options.merge(mark_options), path: mark_path, method: method)
         end
 
         assert_restful_named_routes_for :messages do
@@ -275,24 +277,24 @@ class ResourcesTest < ActionController::TestCase
   end
 
   def test_with_member_action_and_requirement
-    expected_options = {:controller => 'messages', :action => 'mark', :id => '1.1.1'}
+    expected_options = { controller: "messages", action: "mark", id: "1.1.1" }
 
-    with_restful_routing(:messages, :constraints => {:id => /[0-9]\.[0-9]\.[0-9]/}, :member => { :mark => :get }) do
-      assert_recognizes(expected_options, :path => 'messages/1.1.1/mark', :method => :get)
+    with_restful_routing(:messages, constraints: { id: /[0-9]\.[0-9]\.[0-9]/ }, member: { mark: :get }) do
+      assert_recognizes(expected_options, path: "messages/1.1.1/mark", method: :get)
     end
   end
 
   def test_member_when_override_paths_for_default_restful_actions_with
     [:patch, :put, :post].each do |method|
-      with_restful_routing :messages, :member => { :mark => method }, :path_names => {:new => 'nuevo'} do
-        mark_options = {:action => 'mark', :id => '1', :controller => "messages"}
+      with_restful_routing :messages, member: { mark: method }, path_names: { new: "nuevo" } do
+        mark_options = { action: "mark", id: "1", controller: "messages" }
         mark_path    = "/messages/1/mark"
 
-        assert_restful_routes_for :messages, :path_names => {:new => 'nuevo'} do |options|
-          assert_recognizes(options.merge(mark_options), :path => mark_path, :method => method)
+        assert_restful_routes_for :messages, path_names: { new: "nuevo" } do |options|
+          assert_recognizes(options.merge(mark_options), path: mark_path, method: method)
         end
 
-        assert_restful_named_routes_for :messages, :path_names => {:new => 'nuevo'} do
+        assert_restful_named_routes_for :messages, path_names: { new: "nuevo" } do
           assert_named_route mark_path, :mark_message_path, mark_options
         end
       end
@@ -305,17 +307,17 @@ class ResourcesTest < ActionController::TestCase
         set.draw do
           resources :messages do
             member do
-              match :mark  , :via => method
-              match :unmark, :via => method
+              match :mark, via: method
+              match :unmark, via: method
             end
           end
         end
 
         %w(mark unmark).each do |action|
-          action_options = {:action => action, :id => '1'}
+          action_options = { action: action, id: "1" }
           action_path    = "/messages/1/#{action}"
           assert_restful_routes_for :messages do |options|
-            assert_recognizes(options.merge(action_options), :path => action_path, :method => method)
+            assert_recognizes(options.merge(action_options), path: action_path, method: method)
           end
 
           assert_restful_named_routes_for :messages do
@@ -331,21 +333,21 @@ class ResourcesTest < ActionController::TestCase
       set.draw do
         resources :messages do
           collection do
-            match :search, :via => [:post, :get]
+            match :search, via: [:post, :get]
           end
 
           member do
-            match :toggle, :via => [:post, :get]
+            match :toggle, via: [:post, :get]
           end
         end
       end
 
       assert_restful_routes_for :messages do |options|
         [:get, :post].each do |method|
-          assert_recognizes(options.merge(:action => 'search'), :path => "/messages/search", :method => method)
+          assert_recognizes(options.merge(action: "search"), path: "/messages/search", method: method)
         end
         [:get, :post].each do |method|
-          assert_recognizes(options.merge(:action => 'toggle', :id => '1'), :path => '/messages/1/toggle', :method => method)
+          assert_recognizes(options.merge(action: "toggle", id: "1"), path: "/messages/1/toggle", method: method)
         end
       end
     end
@@ -355,14 +357,14 @@ class ResourcesTest < ActionController::TestCase
     with_routing do |set|
       set.draw do
         resources :messages do
-          post :preview, :on => :new
+          post :preview, on: :new
         end
       end
 
-      preview_options = {:action => 'preview'}
+      preview_options = { action: "preview" }
       preview_path    = "/messages/new/preview"
       assert_restful_routes_for :messages do |options|
-        assert_recognizes(options.merge(preview_options), :path => preview_path, :method => :post)
+        assert_recognizes(options.merge(preview_options), path: preview_path, method: :post)
       end
 
       assert_restful_named_routes_for :messages do
@@ -374,20 +376,20 @@ class ResourcesTest < ActionController::TestCase
   def test_with_new_action_with_name_prefix
     with_routing do |set|
       set.draw do
-        scope('/threads/:thread_id') do
-          resources :messages, :as => "thread_messages" do
-            post :preview, :on => :new
+        scope("/threads/:thread_id") do
+          resources :messages, as: "thread_messages" do
+            post :preview, on: :new
           end
         end
       end
 
-      preview_options = {:action => 'preview', :thread_id => '1'}
+      preview_options = { action: "preview", thread_id: "1" }
       preview_path    = "/threads/1/messages/new/preview"
-      assert_restful_routes_for :messages, :path_prefix => 'threads/1/', :name_prefix => 'thread_', :options => { :thread_id => '1' } do |options|
-        assert_recognizes(options.merge(preview_options), :path => preview_path, :method => :post)
+      assert_restful_routes_for :messages, path_prefix: "threads/1/", name_prefix: "thread_", options: { thread_id: "1" } do |options|
+        assert_recognizes(options.merge(preview_options), path: preview_path, method: :post)
       end
 
-      assert_restful_named_routes_for :messages, :path_prefix => 'threads/1/', :name_prefix => 'thread_', :options => { :thread_id => '1' } do
+      assert_restful_named_routes_for :messages, path_prefix: "threads/1/", name_prefix: "thread_", options: { thread_id: "1" } do
         assert_named_route preview_path, :preview_new_thread_message_path, preview_options
       end
     end
@@ -396,20 +398,20 @@ class ResourcesTest < ActionController::TestCase
   def test_with_formatted_new_action_with_name_prefix
     with_routing do |set|
       set.draw do
-        scope('/threads/:thread_id') do
-          resources :messages, :as => "thread_messages" do
-            post :preview, :on => :new
+        scope("/threads/:thread_id") do
+          resources :messages, as: "thread_messages" do
+            post :preview, on: :new
           end
         end
       end
 
-      preview_options = {:action => 'preview', :thread_id => '1', :format => 'xml'}
+      preview_options = { action: "preview", thread_id: "1", format: "xml" }
       preview_path    = "/threads/1/messages/new/preview.xml"
-      assert_restful_routes_for :messages, :path_prefix => 'threads/1/', :name_prefix => 'thread_', :options => { :thread_id => '1' } do |options|
-        assert_recognizes(options.merge(preview_options), :path => preview_path, :method => :post)
+      assert_restful_routes_for :messages, path_prefix: "threads/1/", name_prefix: "thread_", options: { thread_id: "1" } do |options|
+        assert_recognizes(options.merge(preview_options), path: preview_path, method: :post)
       end
 
-      assert_restful_named_routes_for :messages, :path_prefix => 'threads/1/', :name_prefix => 'thread_', :options => { :thread_id => '1' } do
+      assert_restful_named_routes_for :messages, path_prefix: "threads/1/", name_prefix: "thread_", options: { thread_id: "1" } do
         assert_named_route preview_path, :preview_new_thread_message_path, preview_options
       end
     end
@@ -418,9 +420,9 @@ class ResourcesTest < ActionController::TestCase
   def test_override_new_method
     with_restful_routing :messages do
       assert_restful_routes_for :messages do |options|
-        assert_recognizes(options.merge(:action => "new"), :path => "/messages/new", :method => :get)
+        assert_recognizes(options.merge(action: "new"), path: "/messages/new", method: :get)
         assert_raise(ActionController::RoutingError) do
-          @routes.recognize_path("/messages/new", :method => :post)
+          @routes.recognize_path("/messages/new", method: :post)
         end
       end
     end
@@ -428,13 +430,13 @@ class ResourcesTest < ActionController::TestCase
     with_routing do |set|
       set.draw do
         resources :messages do
-          match :new, :via => [:post, :get], :on => :new
+          match :new, via: [:post, :get], on: :new
         end
       end
 
       assert_restful_routes_for :messages do |options|
-        assert_recognizes(options.merge(:action => "new"), :path => "/messages/new", :method => :post)
-        assert_recognizes(options.merge(:action => "new"), :path => "/messages/new", :method => :get)
+        assert_recognizes(options.merge(action: "new"), path: "/messages/new", method: :post)
+        assert_recognizes(options.merge(action: "new"), path: "/messages/new", method: :get)
       end
     end
   end
@@ -451,20 +453,20 @@ class ResourcesTest < ActionController::TestCase
 
       assert_simply_restful_for :threads
       assert_simply_restful_for :messages,
-        :name_prefix => 'thread_',
-        :path_prefix => 'threads/1/',
-        :options => { :thread_id => '1' }
+        name_prefix: "thread_",
+        path_prefix: "threads/1/",
+        options: { thread_id: "1" }
       assert_simply_restful_for :comments,
-        :name_prefix => 'thread_message_',
-        :path_prefix => 'threads/1/messages/2/',
-        :options => { :thread_id => '1', :message_id => '2' }
+        name_prefix: "thread_message_",
+        path_prefix: "threads/1/messages/2/",
+        options: { thread_id: "1", message_id: "2" }
     end
   end
 
   def test_shallow_nested_restful_routes
     with_routing do |set|
       set.draw do
-        resources :threads, :shallow => true do
+        resources :threads, shallow: true do
           resources :messages do
             resources :comments
           end
@@ -472,17 +474,17 @@ class ResourcesTest < ActionController::TestCase
       end
 
       assert_simply_restful_for :threads,
-        :shallow => true
+        shallow: true
       assert_simply_restful_for :messages,
-        :name_prefix => 'thread_',
-        :path_prefix => 'threads/1/',
-        :shallow => true,
-        :options => { :thread_id => '1' }
+        name_prefix: "thread_",
+        path_prefix: "threads/1/",
+        shallow: true,
+        options: { thread_id: "1" }
       assert_simply_restful_for :comments,
-        :name_prefix => 'message_',
-        :path_prefix => 'messages/2/',
-        :shallow => true,
-        :options => { :message_id => '2' }
+        name_prefix: "message_",
+        path_prefix: "messages/2/",
+        shallow: true,
+        options: { message_id: "2" }
     end
   end
 
@@ -491,7 +493,7 @@ class ResourcesTest < ActionController::TestCase
       set.draw do
         namespace :backoffice do
           namespace :admin do
-            resources :products, :shallow => true do
+            resources :products, shallow: true do
               resources :images
             end
           end
@@ -499,18 +501,18 @@ class ResourcesTest < ActionController::TestCase
       end
 
       assert_simply_restful_for :products,
-        :controller => 'backoffice/admin/products',
-        :namespace => 'backoffice/admin/',
-        :name_prefix => 'backoffice_admin_',
-        :path_prefix => 'backoffice/admin/',
-        :shallow => true
+        controller: "backoffice/admin/products",
+        namespace: "backoffice/admin/",
+        name_prefix: "backoffice_admin_",
+        path_prefix: "backoffice/admin/",
+        shallow: true
       assert_simply_restful_for :images,
-        :controller => 'backoffice/admin/images',
-        :namespace => 'backoffice/admin/',
-        :name_prefix => 'backoffice_admin_product_',
-        :path_prefix => 'backoffice/admin/products/1/',
-        :shallow => true,
-        :options => { :product_id => '1' }
+        controller: "backoffice/admin/images",
+        namespace: "backoffice/admin/",
+        name_prefix: "backoffice_admin_product_",
+        path_prefix: "backoffice/admin/products/1/",
+        shallow: true,
+        options: { product_id: "1" }
     end
   end
 
@@ -542,13 +544,13 @@ class ResourcesTest < ActionController::TestCase
   def test_should_create_nested_singleton_resource_routes
     with_routing do |set|
       set.draw do
-        resource :admin, :controller => 'admin' do
+        resource :admin, controller: "admin" do
           resource :account
         end
       end
 
-      assert_singleton_restful_for :admin, :controller => 'admin'
-      assert_singleton_restful_for :account, :name_prefix => "admin_", :path_prefix => 'admin/'
+      assert_singleton_restful_for :admin, controller: "admin"
+      assert_singleton_restful_for :account, name_prefix: "admin_", path_prefix: "admin/"
     end
   end
 
@@ -557,14 +559,14 @@ class ResourcesTest < ActionController::TestCase
       with_routing do |set|
         set.draw do
           resource :account do
-            match :reset, :on => :member, :via => method
+            match :reset, on: :member, via: method
           end
         end
 
-        reset_options = {:action => 'reset'}
+        reset_options = { action: "reset" }
         reset_path    = "/account/reset"
         assert_singleton_routes_for :account do |options|
-          assert_recognizes(options.merge(reset_options), :path => reset_path, :method => method)
+          assert_recognizes(options.merge(reset_options), path: reset_path, method: method)
         end
 
         assert_singleton_named_routes_for :account do
@@ -579,16 +581,16 @@ class ResourcesTest < ActionController::TestCase
       with_routing do |set|
         set.draw do
           resource :account do
-            match :reset, :on => :member, :via => method
-            match :disable, :on => :member, :via => method
+            match :reset, on: :member, via: method
+            match :disable, on: :member, via: method
           end
         end
 
         %w(reset disable).each do |action|
-          action_options = {:action => action}
+          action_options = { action: action }
           action_path    = "/account/#{action}"
           assert_singleton_routes_for :account do |options|
-            assert_recognizes(options.merge(action_options), :path => action_path, :method => method)
+            assert_recognizes(options.merge(action_options), path: action_path, method: method)
           end
 
           assert_singleton_named_routes_for :account do
@@ -608,22 +610,22 @@ class ResourcesTest < ActionController::TestCase
       end
 
       assert_singleton_restful_for :account
-      assert_simply_restful_for :messages, :name_prefix => "account_", :path_prefix => 'account/'
+      assert_simply_restful_for :messages, name_prefix: "account_", path_prefix: "account/"
     end
   end
 
   def test_should_nest_resources_in_singleton_resource_with_path_scope
     with_routing do |set|
       set.draw do
-        scope ':site_id' do
+        scope ":site_id" do
           resource(:account) do
             resources :messages
           end
         end
       end
 
-      assert_singleton_restful_for :account, :path_prefix => '7/', :options => { :site_id => '7' }
-      assert_simply_restful_for :messages, :name_prefix => "account_", :path_prefix => '7/account/', :options => { :site_id => '7' }
+      assert_singleton_restful_for :account, path_prefix: "7/", options: { site_id: "7" }
+      assert_simply_restful_for :messages, name_prefix: "account_", path_prefix: "7/account/", options: { site_id: "7" }
     end
   end
 
@@ -631,31 +633,31 @@ class ResourcesTest < ActionController::TestCase
     with_routing do |set|
       set.draw do
         resources :threads do
-          resource :admin, :controller => 'admin'
+          resource :admin, controller: "admin"
         end
       end
 
       assert_simply_restful_for :threads
-      assert_singleton_restful_for :admin, :controller => 'admin', :name_prefix => 'thread_', :path_prefix => 'threads/5/', :options => { :thread_id => '5' }
+      assert_singleton_restful_for :admin, controller: "admin", name_prefix: "thread_", path_prefix: "threads/5/", options: { thread_id: "5" }
     end
   end
 
   def test_should_not_allow_delete_or_patch_or_put_on_collection_path
     controller_name = :messages
     with_restful_routing controller_name do
-      options = { :controller => controller_name.to_s }
+      options = { controller: controller_name.to_s }
       collection_path = "/#{controller_name}"
 
       assert_raise(Assertion) do
-        assert_recognizes(options.merge(:action => 'update'), :path => collection_path, :method => :patch)
+        assert_recognizes(options.merge(action: "update"), path: collection_path, method: :patch)
       end
 
       assert_raise(Assertion) do
-        assert_recognizes(options.merge(:action => 'update'), :path => collection_path, :method => :put)
+        assert_recognizes(options.merge(action: "update"), path: collection_path, method: :put)
       end
 
       assert_raise(Assertion) do
-        assert_recognizes(options.merge(:action => 'destroy'), :path => collection_path, :method => :delete)
+        assert_recognizes(options.merge(action: "destroy"), path: collection_path, method: :delete)
       end
     end
   end
@@ -663,15 +665,15 @@ class ResourcesTest < ActionController::TestCase
   def test_new_style_named_routes_for_resource
     with_routing do |set|
       set.draw do
-        scope '/threads/:thread_id' do
-          resources :messages, :as => 'thread_messages' do
-            get :search, :on => :collection
-            get :preview, :on => :new
+        scope "/threads/:thread_id" do
+          resources :messages, as: "thread_messages" do
+            get :search, on: :collection
+            get :preview, on: :new
           end
         end
       end
 
-      assert_simply_restful_for :messages, :name_prefix => 'thread_', :path_prefix => 'threads/1/', :options => { :thread_id => '1' }
+      assert_simply_restful_for :messages, name_prefix: "thread_", path_prefix: "threads/1/", options: { thread_id: "1" }
       assert_named_route "/threads/1/messages/search", "search_thread_messages_path", {}
       assert_named_route "/threads/1/messages/new", "new_thread_message_path", {}
       assert_named_route "/threads/1/messages/new/preview", "preview_new_thread_message_path", {}
@@ -681,14 +683,14 @@ class ResourcesTest < ActionController::TestCase
   def test_new_style_named_routes_for_singleton_resource
     with_routing do |set|
       set.draw do
-        scope '/admin' do
-          resource :account, :as => :admin_account do
-            get :login, :on => :member
-            get :preview, :on => :new
+        scope "/admin" do
+          resource :account, as: :admin_account do
+            get :login, on: :member
+            get :preview, on: :new
           end
         end
       end
-      assert_singleton_restful_for :account, :name_prefix => 'admin_', :path_prefix => 'admin/'
+      assert_singleton_restful_for :account, name_prefix: "admin_", path_prefix: "admin/"
       assert_named_route "/admin/account/login", "login_admin_account_path", {}
       assert_named_route "/admin/account/new", "new_admin_account_path", {}
       assert_named_route "/admin/account/new/preview", "preview_new_admin_account_path", {}
@@ -703,7 +705,7 @@ class ResourcesTest < ActionController::TestCase
         end
       end
 
-      assert_simply_restful_for :products, :controller => "backoffice/products", :name_prefix => 'backoffice_', :path_prefix => 'backoffice/'
+      assert_simply_restful_for :products, controller: "backoffice/products", name_prefix: "backoffice_", path_prefix: "backoffice/"
     end
   end
 
@@ -717,19 +719,19 @@ class ResourcesTest < ActionController::TestCase
         end
       end
 
-      assert_simply_restful_for :products, :controller => "backoffice/admin/products", :name_prefix => 'backoffice_admin_', :path_prefix => 'backoffice/admin/'
+      assert_simply_restful_for :products, controller: "backoffice/admin/products", name_prefix: "backoffice_admin_", path_prefix: "backoffice/admin/"
     end
   end
 
   def test_resources_using_namespace
     with_routing do |set|
       set.draw do
-        namespace :backoffice, :path => nil, :as => nil do
+        namespace :backoffice, path: nil, as: nil do
           resources :products
         end
       end
 
-      assert_simply_restful_for :products, :controller => "backoffice/products"
+      assert_simply_restful_for :products, controller: "backoffice/products"
     end
   end
 
@@ -743,7 +745,7 @@ class ResourcesTest < ActionController::TestCase
         end
       end
 
-      assert_simply_restful_for :images, :controller => "backoffice/images", :name_prefix => 'backoffice_product_', :path_prefix => 'backoffice/products/1/', :options => {:product_id => '1'}
+      assert_simply_restful_for :images, controller: "backoffice/images", name_prefix: "backoffice_product_", path_prefix: "backoffice/products/1/", options: { product_id: "1" }
     end
   end
 
@@ -759,107 +761,107 @@ class ResourcesTest < ActionController::TestCase
         end
       end
 
-      assert_simply_restful_for :images, :controller => "backoffice/admin/images", :name_prefix => 'backoffice_admin_product_', :path_prefix => 'backoffice/admin/products/1/', :options => {:product_id => '1'}
+      assert_simply_restful_for :images, controller: "backoffice/admin/images", name_prefix: "backoffice_admin_product_", path_prefix: "backoffice/admin/products/1/", options: { product_id: "1" }
     end
   end
 
   def test_with_path_segment
     with_restful_routing :messages do
       assert_simply_restful_for :messages
-      assert_recognizes({:controller => "messages", :action => "index"}, "/messages")
-      assert_recognizes({:controller => "messages", :action => "index"}, "/messages/")
+      assert_recognizes({ controller: "messages", action: "index" }, "/messages")
+      assert_recognizes({ controller: "messages", action: "index" }, "/messages/")
     end
 
-     with_routing do |set|
-        set.draw do
-          resources :messages, :path => 'reviews'
-        end
-        assert_simply_restful_for :messages, :as => 'reviews'
-        assert_recognizes({:controller => "messages", :action => "index"}, "/reviews")
-        assert_recognizes({:controller => "messages", :action => "index"}, "/reviews/")
-     end
+    with_routing do |set|
+      set.draw do
+        resources :messages, path: "reviews"
+      end
+      assert_simply_restful_for :messages, as: "reviews"
+      assert_recognizes({ controller: "messages", action: "index" }, "/reviews")
+      assert_recognizes({ controller: "messages", action: "index" }, "/reviews/")
+    end
   end
 
   def test_multiple_with_path_segment_and_controller
     with_routing do |set|
       set.draw do
-       resources :products do
-          resources :product_reviews, :path => 'reviews', :controller => 'messages'
-        end
-       resources :tutors do
-          resources :tutor_reviews, :path => 'reviews', :controller => 'comments'
-        end
+        resources :products do
+           resources :product_reviews, path: "reviews", controller: "messages"
+         end
+        resources :tutors do
+           resources :tutor_reviews, path: "reviews", controller: "comments"
+         end
       end
 
-      assert_simply_restful_for :product_reviews, :controller=>'messages', :as => 'reviews', :name_prefix => 'product_', :path_prefix => 'products/1/', :options => {:product_id => '1'}
-      assert_simply_restful_for :tutor_reviews,:controller=>'comments', :as => 'reviews', :name_prefix => 'tutor_', :path_prefix => 'tutors/1/', :options => {:tutor_id => '1'}
+      assert_simply_restful_for :product_reviews, controller: "messages", as: "reviews", name_prefix: "product_", path_prefix: "products/1/", options: { product_id: "1" }
+      assert_simply_restful_for :tutor_reviews, controller: "comments", as: "reviews", name_prefix: "tutor_", path_prefix: "tutors/1/", options: { tutor_id: "1" }
     end
   end
 
   def test_with_path_segment_path_prefix_constraints
-    expected_options = {:controller => 'messages', :action => 'show', :thread_id => '1.1.1', :id => '1'}
+    expected_options = { controller: "messages", action: "show", thread_id: "1.1.1", id: "1" }
     with_routing do |set|
       set.draw do
-        scope '/thread/:thread_id', :constraints => { :thread_id => /[0-9]\.[0-9]\.[0-9]/ } do
-          resources :messages, :path => 'comments'
+        scope "/thread/:thread_id", constraints: { thread_id: /[0-9]\.[0-9]\.[0-9]/ } do
+          resources :messages, path: "comments"
         end
       end
-      assert_recognizes(expected_options, :path => 'thread/1.1.1/comments/1', :method => :get)
+      assert_recognizes(expected_options, path: "thread/1.1.1/comments/1", method: :get)
     end
   end
 
   def test_resource_has_only_show_action
     with_routing do |set|
       set.draw do
-        resources :products, :only => :show
+        resources :products, only: :show
       end
 
-      assert_resource_allowed_routes('products', {},                    { :id => '1' }, :show, [:index, :new, :create, :edit, :update, :destroy])
-      assert_resource_allowed_routes('products', { :format => 'xml' },  { :id => '1' }, :show, [:index, :new, :create, :edit, :update, :destroy])
+      assert_resource_allowed_routes("products", {},                    { id: "1" }, :show, [:index, :new, :create, :edit, :update, :destroy])
+      assert_resource_allowed_routes("products", { format: "xml" },  { id: "1" }, :show, [:index, :new, :create, :edit, :update, :destroy])
     end
   end
 
   def test_singleton_resource_has_only_show_action
     with_routing do |set|
       set.draw do
-        resource :account, :only => :show
+        resource :account, only: :show
       end
 
-      assert_singleton_resource_allowed_routes('accounts', {},                    :show, [:index, :new, :create, :edit, :update, :destroy])
-      assert_singleton_resource_allowed_routes('accounts', { :format => 'xml' },  :show, [:index, :new, :create, :edit, :update, :destroy])
+      assert_singleton_resource_allowed_routes("accounts", {},                    :show, [:index, :new, :create, :edit, :update, :destroy])
+      assert_singleton_resource_allowed_routes("accounts", { format: "xml" },  :show, [:index, :new, :create, :edit, :update, :destroy])
     end
   end
 
   def test_resource_does_not_have_destroy_action
     with_routing do |set|
       set.draw do
-        resources :products, :except => :destroy
+        resources :products, except: :destroy
       end
 
-      assert_resource_allowed_routes('products', {},                    { :id => '1' }, [:index, :new, :create, :show, :edit, :update], :destroy)
-      assert_resource_allowed_routes('products', { :format => 'xml' },  { :id => '1' }, [:index, :new, :create, :show, :edit, :update], :destroy)
+      assert_resource_allowed_routes("products", {},                    { id: "1" }, [:index, :new, :create, :show, :edit, :update], :destroy)
+      assert_resource_allowed_routes("products", { format: "xml" },  { id: "1" }, [:index, :new, :create, :show, :edit, :update], :destroy)
     end
   end
 
   def test_singleton_resource_does_not_have_destroy_action
     with_routing do |set|
       set.draw do
-        resource :account, :except => :destroy
+        resource :account, except: :destroy
       end
 
-      assert_singleton_resource_allowed_routes('accounts', {},                    [:new, :create, :show, :edit, :update], :destroy)
-      assert_singleton_resource_allowed_routes('accounts', { :format => 'xml' },  [:new, :create, :show, :edit, :update], :destroy)
+      assert_singleton_resource_allowed_routes("accounts", {},                    [:new, :create, :show, :edit, :update], :destroy)
+      assert_singleton_resource_allowed_routes("accounts", { format: "xml" },  [:new, :create, :show, :edit, :update], :destroy)
     end
   end
 
   def test_resource_has_only_create_action_and_named_route
     with_routing do |set|
       set.draw do
-        resources :products, :only => :create
+        resources :products, only: :create
       end
 
-      assert_resource_allowed_routes('products', {},                    { :id => '1' }, :create, [:index, :new, :show, :edit, :update, :destroy])
-      assert_resource_allowed_routes('products', { :format => 'xml' },  { :id => '1' }, :create, [:index, :new, :show, :edit, :update, :destroy])
+      assert_resource_allowed_routes("products", {},                    { id: "1" }, :create, [:index, :new, :show, :edit, :update, :destroy])
+      assert_resource_allowed_routes("products", { format: "xml" },  { id: "1" }, :create, [:index, :new, :show, :edit, :update, :destroy])
 
       assert_not_nil set.named_routes[:products]
     end
@@ -868,11 +870,11 @@ class ResourcesTest < ActionController::TestCase
   def test_resource_has_only_update_action_and_named_route
     with_routing do |set|
       set.draw do
-        resources :products, :only => :update
+        resources :products, only: :update
       end
 
-      assert_resource_allowed_routes('products', {},                    { :id => '1' }, :update, [:index, :new, :create, :show, :edit, :destroy])
-      assert_resource_allowed_routes('products', { :format => 'xml' },  { :id => '1' }, :update, [:index, :new, :create, :show, :edit, :destroy])
+      assert_resource_allowed_routes("products", {},                    { id: "1" }, :update, [:index, :new, :create, :show, :edit, :destroy])
+      assert_resource_allowed_routes("products", { format: "xml" },  { id: "1" }, :update, [:index, :new, :create, :show, :edit, :destroy])
 
       assert_not_nil set.named_routes[:product]
     end
@@ -881,11 +883,11 @@ class ResourcesTest < ActionController::TestCase
   def test_resource_has_only_destroy_action_and_named_route
     with_routing do |set|
       set.draw do
-        resources :products, :only => :destroy
+        resources :products, only: :destroy
       end
 
-      assert_resource_allowed_routes('products', {},                    { :id => '1' }, :destroy, [:index, :new, :create, :show, :edit, :update])
-      assert_resource_allowed_routes('products', { :format => 'xml' },  { :id => '1' }, :destroy, [:index, :new, :create, :show, :edit, :update])
+      assert_resource_allowed_routes("products", {},                    { id: "1" }, :destroy, [:index, :new, :create, :show, :edit, :update])
+      assert_resource_allowed_routes("products", { format: "xml" },  { id: "1" }, :destroy, [:index, :new, :create, :show, :edit, :update])
 
       assert_not_nil set.named_routes[:product]
     end
@@ -894,11 +896,11 @@ class ResourcesTest < ActionController::TestCase
   def test_singleton_resource_has_only_create_action_and_named_route
     with_routing do |set|
       set.draw do
-        resource :account, :only => :create
+        resource :account, only: :create
       end
 
-      assert_singleton_resource_allowed_routes('accounts', {},                    :create, [:new, :show, :edit, :update, :destroy])
-      assert_singleton_resource_allowed_routes('accounts', { :format => 'xml' },  :create, [:new, :show, :edit, :update, :destroy])
+      assert_singleton_resource_allowed_routes("accounts", {},                    :create, [:new, :show, :edit, :update, :destroy])
+      assert_singleton_resource_allowed_routes("accounts", { format: "xml" },  :create, [:new, :show, :edit, :update, :destroy])
 
       assert_not_nil set.named_routes[:account]
     end
@@ -907,11 +909,11 @@ class ResourcesTest < ActionController::TestCase
   def test_singleton_resource_has_only_update_action_and_named_route
     with_routing do |set|
       set.draw do
-        resource :account, :only => :update
+        resource :account, only: :update
       end
 
-      assert_singleton_resource_allowed_routes('accounts', {},                    :update, [:new, :create, :show, :edit, :destroy])
-      assert_singleton_resource_allowed_routes('accounts', { :format => 'xml' },  :update, [:new, :create, :show, :edit, :destroy])
+      assert_singleton_resource_allowed_routes("accounts", {},                    :update, [:new, :create, :show, :edit, :destroy])
+      assert_singleton_resource_allowed_routes("accounts", { format: "xml" },  :update, [:new, :create, :show, :edit, :destroy])
 
       assert_not_nil set.named_routes[:account]
     end
@@ -920,11 +922,11 @@ class ResourcesTest < ActionController::TestCase
   def test_singleton_resource_has_only_destroy_action_and_named_route
     with_routing do |set|
       set.draw do
-        resource :account, :only => :destroy
+        resource :account, only: :destroy
       end
 
-      assert_singleton_resource_allowed_routes('accounts', {},                    :destroy, [:new, :create, :show, :edit, :update])
-      assert_singleton_resource_allowed_routes('accounts', { :format => 'xml' },  :destroy, [:new, :create, :show, :edit, :update])
+      assert_singleton_resource_allowed_routes("accounts", {},                    :destroy, [:new, :create, :show, :edit, :update])
+      assert_singleton_resource_allowed_routes("accounts", { format: "xml" },  :destroy, [:new, :create, :show, :edit, :update])
 
       assert_not_nil set.named_routes[:account]
     end
@@ -933,120 +935,120 @@ class ResourcesTest < ActionController::TestCase
   def test_resource_has_only_collection_action
     with_routing do |set|
       set.draw do
-        resources :products, :only => [] do
-          get :sale, :on => :collection
+        resources :products, only: [] do
+          get :sale, on: :collection
         end
       end
 
-      assert_resource_allowed_routes('products', {},                    { :id => '1' }, [], [:index, :new, :create, :show, :edit, :update, :destroy])
-      assert_resource_allowed_routes('products', { :format => 'xml' },  { :id => '1' }, [], [:index, :new, :create, :show, :edit, :update, :destroy])
+      assert_resource_allowed_routes("products", {},                    { id: "1" }, [], [:index, :new, :create, :show, :edit, :update, :destroy])
+      assert_resource_allowed_routes("products", { format: "xml" },  { id: "1" }, [], [:index, :new, :create, :show, :edit, :update, :destroy])
 
-      assert_recognizes({ :controller => 'products', :action => 'sale' },                   :path => 'products/sale',     :method => :get)
-      assert_recognizes({ :controller => 'products', :action => 'sale', :format => 'xml' }, :path => 'products/sale.xml', :method => :get)
+      assert_recognizes({ controller: "products", action: "sale" },                   { path: "products/sale",     method: :get })
+      assert_recognizes({ controller: "products", action: "sale", format: "xml" }, { path: "products/sale.xml", method: :get })
     end
   end
 
   def test_resource_has_only_member_action
     with_routing do |set|
       set.draw do
-        resources :products, :only => [] do
-          get :preview, :on => :member
+        resources :products, only: [] do
+          get :preview, on: :member
         end
       end
 
-      assert_resource_allowed_routes('products', {},                    { :id => '1' }, [], [:index, :new, :create, :show, :edit, :update, :destroy])
-      assert_resource_allowed_routes('products', { :format => 'xml' },  { :id => '1' }, [], [:index, :new, :create, :show, :edit, :update, :destroy])
+      assert_resource_allowed_routes("products", {},                    { id: "1" }, [], [:index, :new, :create, :show, :edit, :update, :destroy])
+      assert_resource_allowed_routes("products", { format: "xml" },  { id: "1" }, [], [:index, :new, :create, :show, :edit, :update, :destroy])
 
-      assert_recognizes({ :controller => 'products', :action => 'preview', :id => '1' },                    :path => 'products/1/preview',      :method => :get)
-      assert_recognizes({ :controller => 'products', :action => 'preview', :id => '1', :format => 'xml' },  :path => 'products/1/preview.xml',  :method => :get)
+      assert_recognizes({ controller: "products", action: "preview", id: "1" },                    { path: "products/1/preview",      method: :get })
+      assert_recognizes({ controller: "products", action: "preview", id: "1", format: "xml" },  { path: "products/1/preview.xml",  method: :get })
     end
   end
 
   def test_singleton_resource_has_only_member_action
     with_routing do |set|
       set.draw do
-        resource :account, :only => [] do
+        resource :account, only: [] do
           member do
             get :signup
           end
         end
       end
 
-      assert_singleton_resource_allowed_routes('accounts', {},                    [], [:new, :create, :show, :edit, :update, :destroy])
-      assert_singleton_resource_allowed_routes('accounts', { :format => 'xml' },  [], [:new, :create, :show, :edit, :update, :destroy])
+      assert_singleton_resource_allowed_routes("accounts", {},                    [], [:new, :create, :show, :edit, :update, :destroy])
+      assert_singleton_resource_allowed_routes("accounts", { format: "xml" },  [], [:new, :create, :show, :edit, :update, :destroy])
 
-      assert_recognizes({ :controller => 'accounts', :action => 'signup' },                   :path => 'account/signup',      :method => :get)
-      assert_recognizes({ :controller => 'accounts', :action => 'signup', :format => 'xml' }, :path => 'account/signup.xml',  :method => :get)
+      assert_recognizes({ controller: "accounts", action: "signup" },                   { path: "account/signup",      method: :get })
+      assert_recognizes({ controller: "accounts", action: "signup", format: "xml" }, { path: "account/signup.xml",  method: :get })
     end
   end
 
   def test_nested_resource_has_only_show_and_member_action
     with_routing do |set|
       set.draw do
-        resources :products, :only => [:index, :show] do
-          resources :images, :only => :show do
-            get :thumbnail, :on => :member
+        resources :products, only: [:index, :show] do
+          resources :images, only: :show do
+            get :thumbnail, on: :member
           end
         end
       end
 
-      assert_resource_allowed_routes('images', { :product_id => '1' },                    { :id => '2' }, :show, [:index, :new, :create, :edit, :update, :destroy], 'products/1/images')
-      assert_resource_allowed_routes('images', { :product_id => '1', :format => 'xml' },  { :id => '2' }, :show, [:index, :new, :create, :edit, :update, :destroy], 'products/1/images')
+      assert_resource_allowed_routes("images", { product_id: "1" },                    { id: "2" }, :show, [:index, :new, :create, :edit, :update, :destroy], "products/1/images")
+      assert_resource_allowed_routes("images", { product_id: "1", format: "xml" },  { id: "2" }, :show, [:index, :new, :create, :edit, :update, :destroy], "products/1/images")
 
-      assert_recognizes({ :controller => 'images', :action => 'thumbnail', :product_id => '1', :id => '2' },                    :path => 'products/1/images/2/thumbnail', :method => :get)
-      assert_recognizes({ :controller => 'images', :action => 'thumbnail', :product_id => '1', :id => '2', :format => 'jpg' },  :path => 'products/1/images/2/thumbnail.jpg', :method => :get)
+      assert_recognizes({ controller: "images", action: "thumbnail", product_id: "1", id: "2" },                    { path: "products/1/images/2/thumbnail", method: :get })
+      assert_recognizes({ controller: "images", action: "thumbnail", product_id: "1", id: "2", format: "jpg" },  { path: "products/1/images/2/thumbnail.jpg", method: :get })
     end
   end
 
   def test_nested_resource_does_not_inherit_only_option
     with_routing do |set|
       set.draw do
-        resources :products, :only => :show do
-          resources :images, :except => :destroy
+        resources :products, only: :show do
+          resources :images, except: :destroy
         end
       end
 
-      assert_resource_allowed_routes('images', { :product_id => '1' },                    { :id => '2' }, [:index, :new, :create, :show, :edit, :update], :destroy, 'products/1/images')
-      assert_resource_allowed_routes('images', { :product_id => '1', :format => 'xml' },  { :id => '2' }, [:index, :new, :create, :show, :edit, :update], :destroy, 'products/1/images')
+      assert_resource_allowed_routes("images", { product_id: "1" },                    { id: "2" }, [:index, :new, :create, :show, :edit, :update], :destroy, "products/1/images")
+      assert_resource_allowed_routes("images", { product_id: "1", format: "xml" },  { id: "2" }, [:index, :new, :create, :show, :edit, :update], :destroy, "products/1/images")
     end
   end
 
   def test_nested_resource_does_not_inherit_only_option_by_default
     with_routing do |set|
       set.draw do
-        resources :products, :only => :show do
+        resources :products, only: :show do
           resources :images
         end
       end
 
-      assert_resource_allowed_routes('images', { :product_id => '1' },                    { :id => '2' }, [:index, :new, :create, :show, :edit, :update, :destroy], [], 'products/1/images')
-      assert_resource_allowed_routes('images', { :product_id => '1', :format => 'xml' },  { :id => '2' }, [:index, :new, :create, :show, :edit, :update, :destroy], [], 'products/1/images')
+      assert_resource_allowed_routes("images", { product_id: "1" },                    { id: "2" }, [:index, :new, :create, :show, :edit, :update, :destroy], [], "products/1/images")
+      assert_resource_allowed_routes("images", { product_id: "1", format: "xml" },  { id: "2" }, [:index, :new, :create, :show, :edit, :update, :destroy], [], "products/1/images")
     end
   end
 
   def test_nested_resource_does_not_inherit_except_option
     with_routing do |set|
       set.draw do
-        resources :products, :except => :show do
-          resources :images, :only => :destroy
+        resources :products, except: :show do
+          resources :images, only: :destroy
         end
       end
 
-      assert_resource_allowed_routes('images', { :product_id => '1' },                    { :id => '2' }, :destroy, [:index, :new, :create, :show, :edit, :update], 'products/1/images')
-      assert_resource_allowed_routes('images', { :product_id => '1', :format => 'xml' },  { :id => '2' }, :destroy, [:index, :new, :create, :show, :edit, :update], 'products/1/images')
+      assert_resource_allowed_routes("images", { product_id: "1" },                    { id: "2" }, :destroy, [:index, :new, :create, :show, :edit, :update], "products/1/images")
+      assert_resource_allowed_routes("images", { product_id: "1", format: "xml" },  { id: "2" }, :destroy, [:index, :new, :create, :show, :edit, :update], "products/1/images")
     end
   end
 
   def test_nested_resource_does_not_inherit_except_option_by_default
     with_routing do |set|
       set.draw do
-        resources :products, :except => :show do
+        resources :products, except: :show do
           resources :images
         end
       end
 
-      assert_resource_allowed_routes('images', { :product_id => '1' },                    { :id => '2' }, [:index, :new, :create, :show, :edit, :update, :destroy], [], 'products/1/images')
-      assert_resource_allowed_routes('images', { :product_id => '1', :format => 'xml' },  { :id => '2' }, [:index, :new, :create, :show, :edit, :update, :destroy], [], 'products/1/images')
+      assert_resource_allowed_routes("images", { product_id: "1" },                    { id: "2" }, [:index, :new, :create, :show, :edit, :update, :destroy], [], "products/1/images")
+      assert_resource_allowed_routes("images", { product_id: "1", format: "xml" },  { id: "2" }, [:index, :new, :create, :show, :edit, :update, :destroy], [], "products/1/images")
     end
   end
 
@@ -1056,8 +1058,8 @@ class ResourcesTest < ActionController::TestCase
         resource :product
       end
 
-      assert_routing '/product', :controller => 'products', :action => 'show'
-      assert set.recognize_path("/product", :method => :get)
+      assert_routing "/product", controller: "products", action: "show"
+      assert set.recognize_path("/product", method: :get)
     end
   end
 
@@ -1089,7 +1091,7 @@ class ResourcesTest < ActionController::TestCase
     end
   end
 
-  protected
+  private
     def with_restful_routing(*args)
       options = args.extract_options!
       collection_methods = options.delete(:collection)
@@ -1099,7 +1101,7 @@ class ResourcesTest < ActionController::TestCase
 
       with_routing do |set|
         set.draw do
-          scope(path_prefix || '') do
+          scope(path_prefix || "") do
             resources(*args) do
               if collection_methods
                 collection do
@@ -1125,7 +1127,7 @@ class ResourcesTest < ActionController::TestCase
 
     def with_singleton_resources(*args)
       with_routing do |set|
-        set.draw {resource(*args) }
+        set.draw { resource(*args) }
         yield
       end
     end
@@ -1169,34 +1171,34 @@ class ResourcesTest < ActionController::TestCase
       formatted_edit_member_path = "#{member_path}/#{edit_action}.xml"
 
       with_options(route_options) do |controller|
-        controller.assert_routing collection_path,            :action => 'index'
-        controller.assert_routing new_path,                   :action => 'new'
-        controller.assert_routing "#{collection_path}.xml",   :action => 'index',            :format => 'xml'
-        controller.assert_routing "#{new_path}.xml",          :action => 'new',              :format => 'xml'
+        controller.assert_routing collection_path,            action: "index"
+        controller.assert_routing new_path,                   action: "new"
+        controller.assert_routing "#{collection_path}.xml",   action: "index",            format: "xml"
+        controller.assert_routing "#{new_path}.xml",          action: "new",              format: "xml"
       end
 
       with_options(options[:shallow_options]) do |controller|
-        controller.assert_routing member_path,                :action => 'show', :id => '1'
-        controller.assert_routing edit_member_path,           :action => 'edit', :id => '1'
-        controller.assert_routing "#{member_path}.xml",       :action => 'show', :id => '1', :format => 'xml'
-        controller.assert_routing formatted_edit_member_path, :action => 'edit', :id => '1', :format => 'xml'
-      end
-
-      assert_recognizes(route_options.merge(:action => 'index'),               :path => collection_path,  :method => :get)
-      assert_recognizes(route_options.merge(:action => 'new'),                 :path => new_path,         :method => :get)
-      assert_recognizes(route_options.merge(:action => 'create'),              :path => collection_path,  :method => :post)
-      assert_recognizes(options[:shallow_options].merge(:action => 'show',    :id => '1'), :path => member_path,      :method => :get)
-      assert_recognizes(options[:shallow_options].merge(:action => 'edit',    :id => '1'), :path => edit_member_path, :method => :get)
-      assert_recognizes(options[:shallow_options].merge(:action => 'update',  :id => '1'), :path => member_path,      :method => :put)
-      assert_recognizes(options[:shallow_options].merge(:action => 'destroy', :id => '1'), :path => member_path,      :method => :delete)
-
-      assert_recognizes(route_options.merge(:action => 'index',  :format => 'xml'), :path => "#{collection_path}.xml",   :method => :get)
-      assert_recognizes(route_options.merge(:action => 'new',    :format => 'xml'), :path => "#{new_path}.xml",          :method => :get)
-      assert_recognizes(route_options.merge(:action => 'create', :format => 'xml'), :path => "#{collection_path}.xml",   :method => :post)
-      assert_recognizes(options[:shallow_options].merge(:action => 'show',    :id => '1', :format => 'xml'), :path => "#{member_path}.xml",       :method => :get)
-      assert_recognizes(options[:shallow_options].merge(:action => 'edit',    :id => '1', :format => 'xml'), :path => formatted_edit_member_path, :method => :get)
-      assert_recognizes(options[:shallow_options].merge(:action => 'update',  :id => '1', :format => 'xml'), :path => "#{member_path}.xml",       :method => :put)
-      assert_recognizes(options[:shallow_options].merge(:action => 'destroy', :id => '1', :format => 'xml'), :path => "#{member_path}.xml",       :method => :delete)
+        controller.assert_routing member_path,                action: "show", id: "1"
+        controller.assert_routing edit_member_path,           action: "edit", id: "1"
+        controller.assert_routing "#{member_path}.xml",       action: "show", id: "1", format: "xml"
+        controller.assert_routing formatted_edit_member_path, action: "edit", id: "1", format: "xml"
+      end
+
+      assert_recognizes(route_options.merge(action: "index"),               path: collection_path,  method: :get)
+      assert_recognizes(route_options.merge(action: "new"),                 path: new_path,         method: :get)
+      assert_recognizes(route_options.merge(action: "create"),              path: collection_path,  method: :post)
+      assert_recognizes(options[:shallow_options].merge(action: "show",    id: "1"), path: member_path,      method: :get)
+      assert_recognizes(options[:shallow_options].merge(action: "edit",    id: "1"), path: edit_member_path, method: :get)
+      assert_recognizes(options[:shallow_options].merge(action: "update",  id: "1"), path: member_path,      method: :put)
+      assert_recognizes(options[:shallow_options].merge(action: "destroy", id: "1"), path: member_path,      method: :delete)
+
+      assert_recognizes(route_options.merge(action: "index",  format: "xml"), path: "#{collection_path}.xml",   method: :get)
+      assert_recognizes(route_options.merge(action: "new",    format: "xml"), path: "#{new_path}.xml",          method: :get)
+      assert_recognizes(route_options.merge(action: "create", format: "xml"), path: "#{collection_path}.xml",   method: :post)
+      assert_recognizes(options[:shallow_options].merge(action: "show",    id: "1", format: "xml"), path: "#{member_path}.xml",       method: :get)
+      assert_recognizes(options[:shallow_options].merge(action: "edit",    id: "1", format: "xml"), path: formatted_edit_member_path, method: :get)
+      assert_recognizes(options[:shallow_options].merge(action: "update",  id: "1", format: "xml"), path: "#{member_path}.xml",       method: :put)
+      assert_recognizes(options[:shallow_options].merge(action: "destroy", id: "1", format: "xml"), path: "#{member_path}.xml",       method: :delete)
 
       yield route_options if block_given?
     end
@@ -1228,7 +1230,7 @@ class ResourcesTest < ActionController::TestCase
       shallow_path = "/#{options[:shallow] ? options[:namespace] : options[:path_prefix]}#{path}"
       full_path = "/#{options[:path_prefix]}#{path}"
       name_prefix = options[:name_prefix]
-      shallow_prefix = options[:shallow] ? options[:namespace].try(:gsub, /\//, '_') : options[:name_prefix]
+      shallow_prefix = options[:shallow] ? options[:namespace].try(:gsub, /\//, "_") : options[:name_prefix]
 
       new_action  = "new"
       edit_action = "edit"
@@ -1238,14 +1240,14 @@ class ResourcesTest < ActionController::TestCase
       end
 
       assert_named_route "#{full_path}", "#{name_prefix}#{controller_name}_path", route_options
-      assert_named_route "#{full_path}.xml", "#{name_prefix}#{controller_name}_path", route_options.merge(:format => 'xml')
-      assert_named_route "#{shallow_path}/1", "#{shallow_prefix}#{singular_name}_path", options[:shallow_options].merge(:id => '1')
-      assert_named_route "#{shallow_path}/1.xml", "#{shallow_prefix}#{singular_name}_path", options[:shallow_options].merge(:id => '1', :format => 'xml')
+      assert_named_route "#{full_path}.xml", "#{name_prefix}#{controller_name}_path", route_options.merge(format: "xml")
+      assert_named_route "#{shallow_path}/1", "#{shallow_prefix}#{singular_name}_path", options[:shallow_options].merge(id: "1")
+      assert_named_route "#{shallow_path}/1.xml", "#{shallow_prefix}#{singular_name}_path", options[:shallow_options].merge(id: "1", format: "xml")
 
       assert_named_route "#{full_path}/#{new_action}", "new_#{name_prefix}#{singular_name}_path", route_options
-      assert_named_route "#{full_path}/#{new_action}.xml", "new_#{name_prefix}#{singular_name}_path", route_options.merge(:format => 'xml')
-      assert_named_route "#{shallow_path}/1/#{edit_action}", "edit_#{shallow_prefix}#{singular_name}_path", options[:shallow_options].merge(:id => '1')
-      assert_named_route "#{shallow_path}/1/#{edit_action}.xml", "edit_#{shallow_prefix}#{singular_name}_path", options[:shallow_options].merge(:id => '1', :format => 'xml')
+      assert_named_route "#{full_path}/#{new_action}.xml", "new_#{name_prefix}#{singular_name}_path", route_options.merge(format: "xml")
+      assert_named_route "#{shallow_path}/1/#{edit_action}", "edit_#{shallow_prefix}#{singular_name}_path", options[:shallow_options].merge(id: "1")
+      assert_named_route "#{shallow_path}/1/#{edit_action}.xml", "edit_#{shallow_prefix}#{singular_name}_path", options[:shallow_options].merge(id: "1", format: "xml")
 
       yield route_options if block_given?
     end
@@ -1260,27 +1262,27 @@ class ResourcesTest < ActionController::TestCase
       formatted_edit_path = "#{full_path}/edit.xml"
 
       with_options route_options do |controller|
-        controller.assert_routing full_path,           :action => 'show'
-        controller.assert_routing new_path,            :action => 'new'
-        controller.assert_routing edit_path,           :action => 'edit'
-        controller.assert_routing "#{full_path}.xml",  :action => 'show', :format => 'xml'
-        controller.assert_routing "#{new_path}.xml",   :action => 'new',  :format => 'xml'
-        controller.assert_routing formatted_edit_path, :action => 'edit', :format => 'xml'
-      end
-
-      assert_recognizes(route_options.merge(:action => 'show'),    :path => full_path, :method => :get)
-      assert_recognizes(route_options.merge(:action => 'new'),     :path => new_path,  :method => :get)
-      assert_recognizes(route_options.merge(:action => 'edit'),    :path => edit_path, :method => :get)
-      assert_recognizes(route_options.merge(:action => 'create'),  :path => full_path, :method => :post)
-      assert_recognizes(route_options.merge(:action => 'update'),  :path => full_path, :method => :put)
-      assert_recognizes(route_options.merge(:action => 'destroy'), :path => full_path, :method => :delete)
-
-      assert_recognizes(route_options.merge(:action => 'show',    :format => 'xml'), :path => "#{full_path}.xml",  :method => :get)
-      assert_recognizes(route_options.merge(:action => 'new',     :format => 'xml'), :path => "#{new_path}.xml",   :method => :get)
-      assert_recognizes(route_options.merge(:action => 'edit',    :format => 'xml'), :path => formatted_edit_path, :method => :get)
-      assert_recognizes(route_options.merge(:action => 'create',  :format => 'xml'), :path => "#{full_path}.xml",  :method => :post)
-      assert_recognizes(route_options.merge(:action => 'update',  :format => 'xml'), :path => "#{full_path}.xml",  :method => :put)
-      assert_recognizes(route_options.merge(:action => 'destroy', :format => 'xml'), :path => "#{full_path}.xml",  :method => :delete)
+        controller.assert_routing full_path,           action: "show"
+        controller.assert_routing new_path,            action: "new"
+        controller.assert_routing edit_path,           action: "edit"
+        controller.assert_routing "#{full_path}.xml",  action: "show", format: "xml"
+        controller.assert_routing "#{new_path}.xml",   action: "new",  format: "xml"
+        controller.assert_routing formatted_edit_path, action: "edit", format: "xml"
+      end
+
+      assert_recognizes(route_options.merge(action: "show"),    path: full_path, method: :get)
+      assert_recognizes(route_options.merge(action: "new"),     path: new_path,  method: :get)
+      assert_recognizes(route_options.merge(action: "edit"),    path: edit_path, method: :get)
+      assert_recognizes(route_options.merge(action: "create"),  path: full_path, method: :post)
+      assert_recognizes(route_options.merge(action: "update"),  path: full_path, method: :put)
+      assert_recognizes(route_options.merge(action: "destroy"), path: full_path, method: :delete)
+
+      assert_recognizes(route_options.merge(action: "show",    format: "xml"), path: "#{full_path}.xml",  method: :get)
+      assert_recognizes(route_options.merge(action: "new",     format: "xml"), path: "#{new_path}.xml",   method: :get)
+      assert_recognizes(route_options.merge(action: "edit",    format: "xml"), path: formatted_edit_path, method: :get)
+      assert_recognizes(route_options.merge(action: "create",  format: "xml"), path: "#{full_path}.xml",  method: :post)
+      assert_recognizes(route_options.merge(action: "update",  format: "xml"), path: "#{full_path}.xml",  method: :put)
+      assert_recognizes(route_options.merge(action: "destroy", format: "xml"), path: "#{full_path}.xml",  method: :delete)
 
       yield route_options if block_given?
     end
@@ -1297,23 +1299,23 @@ class ResourcesTest < ActionController::TestCase
       name_prefix = options[:name_prefix]
 
       assert_named_route "#{full_path}",          "#{name_prefix}#{singleton_name}_path",                route_options
-      assert_named_route "#{full_path}.xml",      "#{name_prefix}#{singleton_name}_path",      route_options.merge(:format => 'xml')
+      assert_named_route "#{full_path}.xml",      "#{name_prefix}#{singleton_name}_path",      route_options.merge(format: "xml")
 
       assert_named_route "#{full_path}/new",      "new_#{name_prefix}#{singleton_name}_path",            route_options
-      assert_named_route "#{full_path}/new.xml",  "new_#{name_prefix}#{singleton_name}_path",  route_options.merge(:format => 'xml')
+      assert_named_route "#{full_path}/new.xml",  "new_#{name_prefix}#{singleton_name}_path",  route_options.merge(format: "xml")
       assert_named_route "#{full_path}/edit",     "edit_#{name_prefix}#{singleton_name}_path",           route_options
-      assert_named_route "#{full_path}/edit.xml", "edit_#{name_prefix}#{singleton_name}_path", route_options.merge(:format => 'xml')
+      assert_named_route "#{full_path}/edit.xml", "edit_#{name_prefix}#{singleton_name}_path", route_options.merge(format: "xml")
     end
 
     def assert_named_route(expected, route, options)
-      actual =  @controller.send(route, options) rescue $!.class.name
+      actual = @controller.send(route, options) rescue $!.class.name
       assert_equal expected, actual, "Error on route: #{route}(#{options.inspect})"
     end
 
     def assert_resource_methods(expected, resource, action_method, method)
       assert_equal expected.length, resource.send("#{action_method}_methods")[method].size, "#{resource.send("#{action_method}_methods")[method].inspect}"
       expected.each do |action|
-        assert resource.send("#{action_method}_methods")[method].include?(action)
+        assert_includes resource.send("#{action_method}_methods")[method], action,
           "#{method} not in #{action_method} methods: #{resource.send("#{action_method}_methods")[method].inspect}"
       end
     end
@@ -1321,41 +1323,41 @@ class ResourcesTest < ActionController::TestCase
     def assert_resource_allowed_routes(controller, options, shallow_options, allowed, not_allowed, path = controller)
       shallow_path = "#{path}/#{shallow_options[:id]}"
       format = options[:format] && ".#{options[:format]}"
-      options.merge!(:controller => controller)
+      options.merge!(controller: controller)
       shallow_options.merge!(options)
 
-      assert_whether_allowed(allowed, not_allowed, options,         'index',    "#{path}#{format}",               :get)
-      assert_whether_allowed(allowed, not_allowed, options,         'new',      "#{path}/new#{format}",           :get)
-      assert_whether_allowed(allowed, not_allowed, options,         'create',   "#{path}#{format}",               :post)
-      assert_whether_allowed(allowed, not_allowed, shallow_options, 'show',     "#{shallow_path}#{format}",       :get)
-      assert_whether_allowed(allowed, not_allowed, shallow_options, 'edit',     "#{shallow_path}/edit#{format}",  :get)
-      assert_whether_allowed(allowed, not_allowed, shallow_options, 'update',   "#{shallow_path}#{format}",       :put)
-      assert_whether_allowed(allowed, not_allowed, shallow_options, 'destroy',  "#{shallow_path}#{format}",       :delete)
+      assert_whether_allowed(allowed, not_allowed, options,         "index",    "#{path}#{format}",               :get)
+      assert_whether_allowed(allowed, not_allowed, options,         "new",      "#{path}/new#{format}",           :get)
+      assert_whether_allowed(allowed, not_allowed, options,         "create",   "#{path}#{format}",               :post)
+      assert_whether_allowed(allowed, not_allowed, shallow_options, "show",     "#{shallow_path}#{format}",       :get)
+      assert_whether_allowed(allowed, not_allowed, shallow_options, "edit",     "#{shallow_path}/edit#{format}",  :get)
+      assert_whether_allowed(allowed, not_allowed, shallow_options, "update",   "#{shallow_path}#{format}",       :put)
+      assert_whether_allowed(allowed, not_allowed, shallow_options, "destroy",  "#{shallow_path}#{format}",       :delete)
     end
 
     def assert_singleton_resource_allowed_routes(controller, options, allowed, not_allowed, path = controller.singularize)
       format = options[:format] && ".#{options[:format]}"
-      options.merge!(:controller => controller)
+      options.merge!(controller: controller)
 
-      assert_whether_allowed(allowed, not_allowed, options, 'new',      "#{path}/new#{format}",   :get)
-      assert_whether_allowed(allowed, not_allowed, options, 'create',   "#{path}#{format}",       :post)
-      assert_whether_allowed(allowed, not_allowed, options, 'show',     "#{path}#{format}",       :get)
-      assert_whether_allowed(allowed, not_allowed, options, 'edit',     "#{path}/edit#{format}",  :get)
-      assert_whether_allowed(allowed, not_allowed, options, 'update',   "#{path}#{format}",       :put)
-      assert_whether_allowed(allowed, not_allowed, options, 'destroy',  "#{path}#{format}",       :delete)
+      assert_whether_allowed(allowed, not_allowed, options, "new",      "#{path}/new#{format}",   :get)
+      assert_whether_allowed(allowed, not_allowed, options, "create",   "#{path}#{format}",       :post)
+      assert_whether_allowed(allowed, not_allowed, options, "show",     "#{path}#{format}",       :get)
+      assert_whether_allowed(allowed, not_allowed, options, "edit",     "#{path}/edit#{format}",  :get)
+      assert_whether_allowed(allowed, not_allowed, options, "update",   "#{path}#{format}",       :put)
+      assert_whether_allowed(allowed, not_allowed, options, "destroy",  "#{path}#{format}",       :delete)
     end
 
     def assert_whether_allowed(allowed, not_allowed, options, action, path, method)
       action = action.to_sym
-      options = options.merge(:action => action.to_s)
-      path_options = { :path => path, :method => method }
+      options = options.merge(action: action.to_s)
+      path_options = { path: path, method: method }
 
       if Array(allowed).include?(action)
         assert_recognizes options, path_options
       elsif Array(not_allowed).include?(action)
         assert_not_recognizes options, path_options
       else
-        raise Assertion, 'Invalid Action has passed'
+        raise Assertion, "Invalid Action has passed"
       end
     end
 
diff --git a/actionpack/test/controller/routing_test.rb b/actionpack/test/controller/routing_test.rb
index 03bf8f8295..ec939e946a 100644
--- a/actionpack/test/controller/routing_test.rb
+++ b/actionpack/test/controller/routing_test.rb
@@ -1,7 +1,9 @@
-require 'abstract_unit'
-require 'controller/fake_controllers'
-require 'active_support/core_ext/object/with_options'
-require 'active_support/core_ext/object/json'
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "controller/fake_controllers"
+require "active_support/core_ext/object/with_options"
+require "active_support/core_ext/object/json"
 
 class MilestonesController < ActionController::Base
   def index() head :ok end
@@ -16,12 +18,12 @@ class UriReservedCharactersRoutingTest < ActiveSupport::TestCase
     @set = ActionDispatch::Routing::RouteSet.new
     @set.draw do
       ActiveSupport::Deprecation.silence do
-        get ':controller/:action/:variable/*additional'
+        get ":controller/:action/:variable/*additional"
       end
     end
 
     safe, unsafe = %w(: @ & = + $ , ;), %w(^ ? # [ ])
-    hex = unsafe.map { |char| '%' + char.unpack('H2').first.upcase }
+    hex = unsafe.map { |char| "%" + char.unpack("H2").first.upcase }
 
     @segment = "#{safe.join}#{unsafe.join}".freeze
     @escaped = "#{safe.join}#{hex.join}".freeze
@@ -29,30 +31,28 @@ class UriReservedCharactersRoutingTest < ActiveSupport::TestCase
 
   def test_route_generation_escapes_unsafe_path_characters
     assert_equal "/content/act#{@escaped}ion/var#{@escaped}iable/add#{@escaped}itional-1/add#{@escaped}itional-2",
-      url_for(@set, {
-        :controller => "content",
-        :action => "act#{@segment}ion",
-        :variable => "var#{@segment}iable",
-        :additional => ["add#{@segment}itional-1", "add#{@segment}itional-2"]
-      })
+      url_for(@set,
+        controller: "content",
+        action: "act#{@segment}ion",
+        variable: "var#{@segment}iable",
+        additional: ["add#{@segment}itional-1", "add#{@segment}itional-2"])
   end
 
   def test_route_recognition_unescapes_path_components
-    options = { :controller => "content",
-                :action => "act#{@segment}ion",
-                :variable => "var#{@segment}iable",
-                :additional => "add#{@segment}itional-1/add#{@segment}itional-2" }
+    options = { controller: "content",
+                action: "act#{@segment}ion",
+                variable: "var#{@segment}iable",
+                additional: "add#{@segment}itional-1/add#{@segment}itional-2" }
     assert_equal options, @set.recognize_path("/content/act#{@escaped}ion/var#{@escaped}iable/add#{@escaped}itional-1/add#{@escaped}itional-2")
   end
 
   def test_route_generation_allows_passing_non_string_values_to_generated_helper
     assert_equal "/content/action/variable/1/2",
-      url_for(@set, {
-        :controller => "content",
-        :action => "action",
-        :variable => "variable",
-        :additional => [1, 2]
-      })
+      url_for(@set,
+        controller: "content",
+        action: "action",
+        variable: "variable",
+        additional: [1, 2])
   end
 end
 
@@ -86,106 +86,122 @@ class LegacyRouteSetTests < ActiveSupport::TestCase
 
   def test_symbols_with_dashes
     rs.draw do
-      get '/:artist/:song-omg', :to => lambda { |env|
+      get "/:artist/:song-omg", to: lambda { |env|
         resp = ActiveSupport::JSON.encode ActionDispatch::Request.new(env).path_parameters
         [200, {}, [resp]]
       }
     end
 
-    hash = ActiveSupport::JSON.decode get(URI('http://example.org/journey/faithfully-omg'))
-    assert_equal({"artist"=>"journey", "song"=>"faithfully"}, hash)
+    hash = ActiveSupport::JSON.decode get(URI("http://example.org/journey/faithfully-omg"))
+    assert_equal({ "artist" => "journey", "song" => "faithfully" }, hash)
+  end
+
+  def test_id_encoding
+    rs.draw do
+      get "/journey/:id", to: lambda { |env|
+        param = ActionDispatch::Request.new(env).path_parameters
+        resp = ActiveSupport::JSON.encode param
+        [200, {}, [resp]]
+      }
+    end
+
+    # The encoding of the URL in production is *binary*, so we add a
+    # .b here.
+    hash = ActiveSupport::JSON.decode get(URI("http://example.org/journey/%E5%A4%AA%E9%83%8E".b))
+    assert_equal({ "id" => "太郎" }, hash)
+    assert_equal ::Encoding::UTF_8, hash["id"].encoding
   end
 
   def test_id_with_dash
     rs.draw do
-      get '/journey/:id', :to => lambda { |env|
+      get "/journey/:id", to: lambda { |env|
         resp = ActiveSupport::JSON.encode ActionDispatch::Request.new(env).path_parameters
         [200, {}, [resp]]
       }
     end
 
-    hash = ActiveSupport::JSON.decode get(URI('http://example.org/journey/faithfully-omg'))
-    assert_equal({"id"=>"faithfully-omg"}, hash)
+    hash = ActiveSupport::JSON.decode get(URI("http://example.org/journey/faithfully-omg"))
+    assert_equal({ "id" => "faithfully-omg" }, hash)
   end
 
   def test_dash_with_custom_regexp
     rs.draw do
-      get '/:artist/:song-omg', :constraints => { :song => /\d+/ }, :to => lambda { |env|
+      get "/:artist/:song-omg", constraints: { song: /\d+/ }, to: lambda { |env|
         resp = ActiveSupport::JSON.encode ActionDispatch::Request.new(env).path_parameters
         [200, {}, [resp]]
       }
     end
 
-    hash = ActiveSupport::JSON.decode get(URI('http://example.org/journey/123-omg'))
-    assert_equal({"artist"=>"journey", "song"=>"123"}, hash)
-    assert_equal 'Not Found', get(URI('http://example.org/journey/faithfully-omg'))
+    hash = ActiveSupport::JSON.decode get(URI("http://example.org/journey/123-omg"))
+    assert_equal({ "artist" => "journey", "song" => "123" }, hash)
+    assert_equal "Not Found", get(URI("http://example.org/journey/faithfully-omg"))
   end
 
   def test_pre_dash
     rs.draw do
-      get '/:artist/omg-:song', :to => lambda { |env|
+      get "/:artist/omg-:song", to: lambda { |env|
         resp = ActiveSupport::JSON.encode ActionDispatch::Request.new(env).path_parameters
         [200, {}, [resp]]
       }
     end
 
-    hash = ActiveSupport::JSON.decode get(URI('http://example.org/journey/omg-faithfully'))
-    assert_equal({"artist"=>"journey", "song"=>"faithfully"}, hash)
+    hash = ActiveSupport::JSON.decode get(URI("http://example.org/journey/omg-faithfully"))
+    assert_equal({ "artist" => "journey", "song" => "faithfully" }, hash)
   end
 
   def test_pre_dash_with_custom_regexp
     rs.draw do
-      get '/:artist/omg-:song', :constraints => { :song => /\d+/ }, :to => lambda { |env|
+      get "/:artist/omg-:song", constraints: { song: /\d+/ }, to: lambda { |env|
         resp = ActiveSupport::JSON.encode ActionDispatch::Request.new(env).path_parameters
         [200, {}, [resp]]
       }
     end
 
-    hash = ActiveSupport::JSON.decode get(URI('http://example.org/journey/omg-123'))
-    assert_equal({"artist"=>"journey", "song"=>"123"}, hash)
-    assert_equal 'Not Found', get(URI('http://example.org/journey/omg-faithfully'))
+    hash = ActiveSupport::JSON.decode get(URI("http://example.org/journey/omg-123"))
+    assert_equal({ "artist" => "journey", "song" => "123" }, hash)
+    assert_equal "Not Found", get(URI("http://example.org/journey/omg-faithfully"))
   end
 
   def test_star_paths_are_greedy
     rs.draw do
-      get "/*path", :to => lambda { |env|
+      get "/*path", to: lambda { |env|
         x = env["action_dispatch.request.path_parameters"][:path]
         [200, {}, [x]]
-      }, :format => false
+      }, format: false
     end
 
-    u = URI('http://example.org/foo/bar.html')
-    assert_equal u.path.sub(/^\//, ''), get(u)
+    u = URI("http://example.org/foo/bar.html")
+    assert_equal u.path.sub(/^\//, ""), get(u)
   end
 
   def test_star_paths_are_greedy_but_not_too_much
     rs.draw do
-      get "/*path", :to => lambda { |env|
+      get "/*path", to: lambda { |env|
         x = ActiveSupport::JSON.encode env["action_dispatch.request.path_parameters"]
         [200, {}, [x]]
       }
     end
 
     expected = { "path" => "foo/bar", "format" => "html" }
-    u = URI('http://example.org/foo/bar.html')
+    u = URI("http://example.org/foo/bar.html")
     assert_equal expected, ActiveSupport::JSON.decode(get(u))
   end
 
   def test_optional_star_paths_are_greedy
     rs.draw do
-      get "/(*filters)", :to => lambda { |env|
+      get "/(*filters)", to: lambda { |env|
         x = env["action_dispatch.request.path_parameters"][:filters]
         [200, {}, [x]]
-      }, :format => false
+      }, format: false
     end
 
-    u = URI('http://example.org/ne_27.065938,-80.6092/sw_25.489856,-82.542794')
-    assert_equal u.path.sub(/^\//, ''), get(u)
+    u = URI("http://example.org/ne_27.065938,-80.6092/sw_25.489856,-82.542794")
+    assert_equal u.path.sub(/^\//, ""), get(u)
   end
 
   def test_optional_star_paths_are_greedy_but_not_too_much
     rs.draw do
-      get "/(*filters)", :to => lambda { |env|
+      get "/(*filters)", to: lambda { |env|
         x = ActiveSupport::JSON.encode env["action_dispatch.request.path_parameters"]
         [200, {}, [x]]
       }
@@ -193,65 +209,65 @@ class LegacyRouteSetTests < ActiveSupport::TestCase
 
     expected = { "filters" => "ne_27.065938,-80.6092/sw_25.489856,-82",
                  "format"  => "542794" }
-    u = URI('http://example.org/ne_27.065938,-80.6092/sw_25.489856,-82.542794')
+    u = URI("http://example.org/ne_27.065938,-80.6092/sw_25.489856,-82.542794")
     assert_equal expected, ActiveSupport::JSON.decode(get(u))
   end
 
-  def test_regexp_precidence
+  def test_regexp_precedence
     rs.draw do
-      get '/whois/:domain', :constraints => {
-        :domain => /\w+\.[\w\.]+/ },
-        :to     => lambda { |env| [200, {}, %w{regexp}] }
+      get "/whois/:domain", constraints: {
+        domain: /\w+\.[\w\.]+/ },
+        to: lambda { |env| [200, {}, %w{regexp}] }
 
-      get '/whois/:id', :to => lambda { |env| [200, {}, %w{id}] }
+      get "/whois/:id", to: lambda { |env| [200, {}, %w{id}] }
     end
 
-    assert_equal 'regexp', get(URI('http://example.org/whois/example.org'))
-    assert_equal 'id', get(URI('http://example.org/whois/123'))
+    assert_equal "regexp", get(URI("http://example.org/whois/example.org"))
+    assert_equal "id", get(URI("http://example.org/whois/123"))
   end
 
   def test_class_and_lambda_constraints
     subdomain = Class.new {
-      def matches? request
-        request.subdomain.present? and request.subdomain != 'clients'
+      def matches?(request)
+        request.subdomain.present? && request.subdomain != "clients"
       end
     }
 
     rs.draw do
-      get '/', :constraints => subdomain.new,
-                 :to          => lambda { |env| [200, {}, %w{default}] }
-      get '/', :constraints => { :subdomain => 'clients' },
-                 :to          => lambda { |env| [200, {}, %w{clients}] }
+      get "/", constraints: subdomain.new,
+                 to: lambda { |env| [200, {}, %w{default}] }
+      get "/", constraints: { subdomain: "clients" },
+                 to: lambda { |env| [200, {}, %w{clients}] }
     end
 
-    assert_equal 'default', get(URI('http://www.example.org/'))
-    assert_equal 'clients', get(URI('http://clients.example.org/'))
+    assert_equal "default", get(URI("http://www.example.org/"))
+    assert_equal "clients", get(URI("http://clients.example.org/"))
   end
 
   def test_lambda_constraints
     rs.draw do
-      get '/', :constraints => lambda { |req|
-        req.subdomain.present? and req.subdomain != "clients" },
-                 :to          => lambda { |env| [200, {}, %w{default}] }
+      get "/", constraints: lambda { |req|
+        req.subdomain.present? && req.subdomain != "clients" },
+                 to: lambda { |env| [200, {}, %w{default}] }
 
-      get '/', :constraints => lambda { |req|
+      get "/", constraints: lambda { |req|
         req.subdomain.present? && req.subdomain == "clients" },
-                 :to          => lambda { |env| [200, {}, %w{clients}] }
+                 to: lambda { |env| [200, {}, %w{clients}] }
     end
 
-    assert_equal 'default', get(URI('http://www.example.org/'))
-    assert_equal 'clients', get(URI('http://clients.example.org/'))
+    assert_equal "default", get(URI("http://www.example.org/"))
+    assert_equal "clients", get(URI("http://clients.example.org/"))
   end
 
   def test_scoped_lambda
     scope_called = false
     rs.draw do
-      scope '/foo', :constraints => lambda { |req| scope_called = true } do
-        get '/', :to => lambda { |env| [200, {}, %w{default}] }
+      scope "/foo", constraints: lambda { |req| scope_called = true } do
+        get "/", to: lambda { |env| [200, {}, %w{default}] }
       end
     end
 
-    assert_equal 'default', get(URI('http://www.example.org/foo/'))
+    assert_equal "default", get(URI("http://www.example.org/foo/"))
     assert scope_called, "scope constraint should be called"
   end
 
@@ -259,36 +275,36 @@ class LegacyRouteSetTests < ActiveSupport::TestCase
     inner_called = false
 
     rs.draw do
-      scope '/foo', :constraints => lambda { |req| flunk "should not be called" } do
-        get '/', :constraints    => lambda { |req| inner_called = true },
-                 :to             => lambda { |env| [200, {}, %w{default}] }
+      scope "/foo", constraints: lambda { |req| flunk "should not be called" } do
+        get "/", constraints: lambda { |req| inner_called = true },
+                 to: lambda { |env| [200, {}, %w{default}] }
       end
     end
 
-    assert_equal 'default', get(URI('http://www.example.org/foo/'))
+    assert_equal "default", get(URI("http://www.example.org/foo/"))
     assert inner_called, "inner constraint should be called"
   end
 
   def test_empty_string_match
     rs.draw do
-      get '/:username', :constraints => { :username => /[^\/]+/ },
-                       :to => lambda { |e| [200, {}, ['foo']] }
+      get "/:username", constraints: { username: /[^\/]+/ },
+                       to: lambda { |e| [200, {}, ["foo"]] }
     end
-    assert_equal 'Not Found', get(URI('http://example.org/'))
-    assert_equal 'foo', get(URI('http://example.org/hello'))
+    assert_equal "Not Found", get(URI("http://example.org/"))
+    assert_equal "foo", get(URI("http://example.org/hello"))
   end
 
   def test_non_greedy_glob_regexp
     params = nil
     rs.draw do
-      get '/posts/:id(/*filters)', :constraints => { :filters => /.+?/ },
-        :to => lambda { |e|
+      get "/posts/:id(/*filters)", constraints: { filters: /.+?/ },
+        to: lambda { |e|
         params = e["action_dispatch.request.path_parameters"]
-        [200, {}, ['foo']]
+        [200, {}, ["foo"]]
       }
     end
-    assert_equal 'foo', get(URI('http://example.org/posts/1/foo.js'))
-    assert_equal({:id=>"1", :filters=>"foo", :format=>"js"}, params)
+    assert_equal "foo", get(URI("http://example.org/posts/1/foo.js"))
+    assert_equal({ id: "1", filters: "foo", format: "js" }, params)
   end
 
   def test_specific_controller_action_failure
@@ -297,136 +313,136 @@ class LegacyRouteSetTests < ActiveSupport::TestCase
     end
 
     assert_raises(ActionController::UrlGenerationError) do
-      url_for(rs, :controller => "omg", :action => "lol")
+      url_for(rs, controller: "omg", action: "lol")
     end
   end
 
   def test_default_setup
-    rs.draw { ActiveSupport::Deprecation.silence { get '/:controller(/:action(/:id))' } }
-    assert_equal({:controller => "content", :action => 'index'}, rs.recognize_path("/content"))
-    assert_equal({:controller => "content", :action => 'list'},  rs.recognize_path("/content/list"))
-    assert_equal({:controller => "content", :action => 'show', :id => '10'}, rs.recognize_path("/content/show/10"))
+    rs.draw { ActiveSupport::Deprecation.silence { get "/:controller(/:action(/:id))" } }
+    assert_equal({ controller: "content", action: "index" }, rs.recognize_path("/content"))
+    assert_equal({ controller: "content", action: "list" },  rs.recognize_path("/content/list"))
+    assert_equal({ controller: "content", action: "show", id: "10" }, rs.recognize_path("/content/show/10"))
 
-    assert_equal({:controller => "admin/user", :action => 'show', :id => '10'}, rs.recognize_path("/admin/user/show/10"))
+    assert_equal({ controller: "admin/user", action: "show", id: "10" }, rs.recognize_path("/admin/user/show/10"))
 
-    assert_equal '/admin/user/show/10', url_for(rs, { :controller => 'admin/user', :action => 'show', :id => 10 })
+    assert_equal "/admin/user/show/10", url_for(rs, controller: "admin/user", action: "show", id: 10)
 
-    get URI('http://test.host/admin/user/list/10')
+    get URI("http://test.host/admin/user/list/10")
 
-    assert_equal({ :controller => 'admin/user', :action => 'list', :id => '10' },
+    assert_equal({ controller: "admin/user", action: "list", id: "10" },
                  controller.request.path_parameters)
 
-    assert_equal '/admin/user/show',    controller.url_for({ :action => 'show', :only_path => true })
-    assert_equal '/admin/user/list/10', controller.url_for({:only_path => true})
+    assert_equal "/admin/user/show",    controller.url_for(action: "show", only_path: true)
+    assert_equal "/admin/user/list/10", controller.url_for(only_path: true)
 
-    assert_equal '/admin/stuff', controller.url_for({ :controller => 'stuff', :only_path => true })
-    assert_equal '/stuff', controller.url_for({ :controller => '/stuff', :only_path => true })
+    assert_equal "/admin/stuff", controller.url_for(controller: "stuff", only_path: true)
+    assert_equal "/stuff", controller.url_for(controller: "/stuff", only_path: true)
   end
 
   def test_route_with_colon_first
     rs.draw do
       ActiveSupport::Deprecation.silence do
-        get '/:controller/:action/:id', action: 'index', id: nil
+        get "/:controller/:action/:id", action: "index", id: nil
       end
 
-      get ':url', controller: 'content', action: 'translate'
+      get ":url", controller: "content", action: "translate"
     end
 
-    assert_equal({controller: 'content', action: 'translate', url: 'example'}, rs.recognize_path('/example'))
+    assert_equal({ controller: "content", action: "translate", url: "example" }, rs.recognize_path("/example"))
   end
 
   def test_route_with_regexp_for_action
-    rs.draw { ActiveSupport::Deprecation.silence { get '/:controller/:action', action: /auth[-|_].+/ } }
+    rs.draw { ActiveSupport::Deprecation.silence { get "/:controller/:action", action: /auth[-|_].+/ } }
 
-    assert_equal({ action: 'auth_google', controller: 'content' }, rs.recognize_path('/content/auth_google'))
-    assert_equal({ action: 'auth-facebook', controller: 'content' }, rs.recognize_path('/content/auth-facebook'))
+    assert_equal({ action: "auth_google", controller: "content" }, rs.recognize_path("/content/auth_google"))
+    assert_equal({ action: "auth-facebook", controller: "content" }, rs.recognize_path("/content/auth-facebook"))
 
-    assert_equal '/content/auth_google', url_for(rs, { controller: "content", action: "auth_google" })
-    assert_equal '/content/auth-facebook', url_for(rs, { controller: "content", action: "auth-facebook" })
+    assert_equal "/content/auth_google", url_for(rs, controller: "content", action: "auth_google")
+    assert_equal "/content/auth-facebook", url_for(rs, controller: "content", action: "auth-facebook")
   end
 
   def test_route_with_regexp_for_controller
     rs.draw do
       ActiveSupport::Deprecation.silence do
-        get ':controller/:admintoken(/:action(/:id))', :controller => /admin\/.+/
-        get '/:controller(/:action(/:id))'
+        get ":controller/:admintoken(/:action(/:id))", controller: /admin\/.+/
+        get "/:controller(/:action(/:id))"
       end
     end
 
-    assert_equal({:controller => "admin/user", :admintoken => "foo", :action => "index"},
+    assert_equal({ controller: "admin/user", admintoken: "foo", action: "index" },
         rs.recognize_path("/admin/user/foo"))
-    assert_equal({:controller => "content", :action => "foo"},
+    assert_equal({ controller: "content", action: "foo" },
         rs.recognize_path("/content/foo"))
 
-    assert_equal '/admin/user/foo', url_for(rs, { :controller => "admin/user", :admintoken => "foo", :action => "index" })
-    assert_equal '/content/foo',    url_for(rs, { :controller => "content", :action => "foo" })
+    assert_equal "/admin/user/foo", url_for(rs, controller: "admin/user", admintoken: "foo", action: "index")
+    assert_equal "/content/foo",    url_for(rs, controller: "content", action: "foo")
   end
 
   def test_route_with_regexp_and_captures_for_controller
     rs.draw do
       ActiveSupport::Deprecation.silence do
-        get '/:controller(/:action(/:id))', :controller => /admin\/(accounts|users)/
+        get "/:controller(/:action(/:id))", controller: /admin\/(accounts|users)/
       end
     end
-    assert_equal({:controller => "admin/accounts", :action => "index"}, rs.recognize_path("/admin/accounts"))
-    assert_equal({:controller => "admin/users", :action => "index"}, rs.recognize_path("/admin/users"))
+    assert_equal({ controller: "admin/accounts", action: "index" }, rs.recognize_path("/admin/accounts"))
+    assert_equal({ controller: "admin/users", action: "index" }, rs.recognize_path("/admin/users"))
     assert_raise(ActionController::RoutingError) { rs.recognize_path("/admin/products") }
   end
 
   def test_route_with_regexp_and_dot
     rs.draw do
       ActiveSupport::Deprecation.silence do
-        get ':controller/:action/:file',
-                  :controller => /admin|user/,
-                  :action => /upload|download/,
-                  :defaults => {:file => nil},
-                  :constraints => {:file => %r{[^/]+(\.[^/]+)?}}
+        get ":controller/:action/:file",
+                  controller: /admin|user/,
+                  action: /upload|download/,
+                  defaults: { file: nil },
+                  constraints: { file: %r{[^/]+(\.[^/]+)?} }
       end
     end
     # Without a file extension
-    assert_equal '/user/download/file',
-      url_for(rs, { :controller => "user", :action => "download", :file => "file" })
+    assert_equal "/user/download/file",
+      url_for(rs, controller: "user", action: "download", file: "file")
 
-    assert_equal({:controller => "user", :action => "download", :file => "file"},
+    assert_equal({ controller: "user", action: "download", file: "file" },
       rs.recognize_path("/user/download/file"))
 
     # Now, let's try a file with an extension, really a dot (.)
-    assert_equal '/user/download/file.jpg',
-      url_for(rs, { :controller => "user", :action => "download", :file => "file.jpg" })
+    assert_equal "/user/download/file.jpg",
+      url_for(rs, controller: "user", action: "download", file: "file.jpg")
 
-    assert_equal({:controller => "user", :action => "download", :file => "file.jpg"},
+    assert_equal({ controller: "user", action: "download", file: "file.jpg" },
       rs.recognize_path("/user/download/file.jpg"))
   end
 
   def test_basic_named_route
     rs.draw do
-      root :to => 'content#list', :as => 'home'
+      root to: "content#list", as: "home"
     end
     assert_equal("http://test.host/", setup_for_named_route.send(:home_url))
   end
 
   def test_named_route_with_option
     rs.draw do
-      get 'page/:title' => 'content#show_page', :as => 'page'
+      get "page/:title" => "content#show_page", :as => "page"
     end
 
     assert_equal("http://test.host/page/new%20stuff",
-        setup_for_named_route.send(:page_url, :title => 'new stuff'))
+        setup_for_named_route.send(:page_url, title: "new stuff"))
   end
 
   def test_named_route_with_default
     rs.draw do
-      get 'page/:title' => 'content#show_page', :title => 'AboutPage', :as => 'page'
+      get "page/:title" => "content#show_page", :title => "AboutPage", :as => "page"
     end
 
     assert_equal("http://test.host/page/AboutRails",
-        setup_for_named_route.send(:page_url, :title => "AboutRails"))
+        setup_for_named_route.send(:page_url, title: "AboutRails"))
   end
 
   def test_named_route_with_path_prefix
     rs.draw do
       scope "my" do
-        get 'page' => 'content#show_page', :as => 'page'
+        get "page" => "content#show_page", :as => "page"
       end
     end
 
@@ -437,7 +453,7 @@ class LegacyRouteSetTests < ActiveSupport::TestCase
   def test_named_route_with_blank_path_prefix
     rs.draw do
       scope "" do
-        get 'page' => 'content#show_page', :as => 'page'
+        get "page" => "content#show_page", :as => "page"
       end
     end
 
@@ -447,7 +463,7 @@ class LegacyRouteSetTests < ActiveSupport::TestCase
 
   def test_named_route_with_nested_controller
     rs.draw do
-      get 'admin/user' => 'admin/user#index', :as => "users"
+      get "admin/user" => "admin/user#index", :as => "users"
     end
 
     assert_equal("http://test.host/admin/user",
@@ -456,7 +472,7 @@ class LegacyRouteSetTests < ActiveSupport::TestCase
 
   def test_optimised_named_route_with_host
     rs.draw do
-      get 'page' => 'content#show_page', :as => 'pages', :host => 'foo.com'
+      get "page" => "content#show_page", :as => "pages", :host => "foo.com"
     end
     routes = setup_for_named_route
     assert_equal "http://foo.com/page", routes.pages_url
@@ -469,14 +485,14 @@ class LegacyRouteSetTests < ActiveSupport::TestCase
   def test_named_route_without_hash
     rs.draw do
       ActiveSupport::Deprecation.silence do
-        get ':controller/:action/:id', :as => 'normal'
+        get ":controller/:action/:id", as: "normal"
       end
     end
   end
 
   def test_named_route_root
     rs.draw do
-      root :to => "hello#index"
+      root to: "hello#index"
     end
     routes = setup_for_named_route
     assert_equal("http://test.host/", routes.send(:root_url))
@@ -520,62 +536,62 @@ class LegacyRouteSetTests < ActiveSupport::TestCase
 
   def test_named_route_with_regexps
     rs.draw do
-      get 'page/:year/:month/:day/:title' => 'page#show', :as => 'article',
+      get "page/:year/:month/:day/:title" => "page#show", :as => "article",
         :year => /\d+/, :month => /\d+/, :day => /\d+/
 
       ActiveSupport::Deprecation.silence do
-        get ':controller/:action/:id'
+        get ":controller/:action/:id"
       end
     end
 
     routes = setup_for_named_route
 
     assert_equal "http://test.host/page/2005/6/10/hi",
-      routes.send(:article_url, :title => 'hi', :day => 10, :year => 2005, :month => 6)
+      routes.send(:article_url, title: "hi", day: 10, year: 2005, month: 6)
   end
 
   def test_changing_controller
-    rs.draw { ActiveSupport::Deprecation.silence { get ':controller/:action/:id' } }
+    rs.draw { ActiveSupport::Deprecation.silence { get ":controller/:action/:id" } }
 
-    get URI('http://test.host/admin/user/index/10')
+    get URI("http://test.host/admin/user/index/10")
 
-    assert_equal '/admin/stuff/show/10',
-        controller.url_for({:controller => 'stuff', :action => 'show', :id => 10, :only_path => true})
+    assert_equal "/admin/stuff/show/10",
+        controller.url_for(controller: "stuff", action: "show", id: 10, only_path: true)
   end
 
   def test_paths_escaped
     rs.draw do
-      get 'file/*path' => 'content#show_file', :as => 'path'
+      get "file/*path" => "content#show_file", :as => "path"
 
       ActiveSupport::Deprecation.silence do
-        get ':controller/:action/:id'
+        get ":controller/:action/:id"
       end
     end
 
     # No + to space in URI escaping, only for query params.
     results = rs.recognize_path "/file/hello+world/how+are+you%3F"
     assert results, "Recognition should have succeeded"
-    assert_equal 'hello+world/how+are+you?', results[:path]
+    assert_equal "hello+world/how+are+you?", results[:path]
 
     # Use %20 for space instead.
     results = rs.recognize_path "/file/hello%20world/how%20are%20you%3F"
     assert results, "Recognition should have succeeded"
-    assert_equal 'hello world/how are you?', results[:path]
+    assert_equal "hello world/how are you?", results[:path]
   end
 
   def test_paths_slashes_unescaped_with_ordered_parameters
     rs.draw do
-      get '/file/*path' => 'content#index', :as => 'path'
+      get "/file/*path" => "content#index", :as => "path"
     end
 
     # No / to %2F in URI, only for query params.
-    assert_equal("/file/hello/world", setup_for_named_route.send(:path_path, ['hello', 'world']))
+    assert_equal("/file/hello/world", setup_for_named_route.send(:path_path, ["hello", "world"]))
   end
 
   def test_non_controllers_cannot_be_matched
     rs.draw do
       ActiveSupport::Deprecation.silence do
-        get ':controller/:action/:id'
+        get ":controller/:action/:id"
       end
     end
     assert_raise(ActionController::RoutingError) { rs.recognize_path("/not_a/show/10") }
@@ -583,186 +599,186 @@ class LegacyRouteSetTests < ActiveSupport::TestCase
 
   def test_should_list_options_diff_when_routing_constraints_dont_match
     rs.draw do
-      get 'post/:id' => 'post#show', :constraints => { :id => /\d+/ }, :as => 'post'
+      get "post/:id" => "post#show", :constraints => { id: /\d+/ }, :as => "post"
     end
     assert_raise(ActionController::UrlGenerationError) do
-      url_for(rs, { :controller => 'post', :action => 'show', :bad_param => "foo", :use_route => "post" })
+      url_for(rs, controller: "post", action: "show", bad_param: "foo", use_route: "post")
     end
   end
 
   def test_dynamic_path_allowed
     rs.draw do
-      get '*path' => 'content#show_file'
+      get "*path" => "content#show_file"
     end
 
-    assert_equal '/pages/boo',
-        url_for(rs, { :controller => 'content', :action => 'show_file', :path => %w(pages boo) })
+    assert_equal "/pages/boo",
+        url_for(rs, controller: "content", action: "show_file", path: %w(pages boo))
   end
 
   def test_dynamic_recall_paths_allowed
     rs.draw do
-      get '*path' => 'content#show_file'
+      get "*path" => "content#show_file"
     end
 
-    get URI('http://test.host/pages/boo')
-    assert_equal({:controller=>"content", :action=>"show_file", :path=>"pages/boo"},
+    get URI("http://test.host/pages/boo")
+    assert_equal({ controller: "content", action: "show_file", path: "pages/boo" },
                  controller.request.path_parameters)
 
-    assert_equal '/pages/boo',
-      controller.url_for(:only_path => true)
+    assert_equal "/pages/boo",
+      controller.url_for(only_path: true)
   end
 
   def test_backwards
     rs.draw do
       ActiveSupport::Deprecation.silence do
-        get 'page/:id(/:action)' => 'pages#show'
-        get ':controller(/:action(/:id))'
+        get "page/:id(/:action)" => "pages#show"
+        get ":controller(/:action(/:id))"
       end
     end
 
-    get URI('http://test.host/pages/show')
-    assert_equal '/page/20',   controller.url_for({ :id => 20, :only_path => true })
-    assert_equal '/page/20',   url_for(rs, { :controller => 'pages', :id => 20, :action => 'show' })
-    assert_equal '/pages/boo', url_for(rs, { :controller => 'pages', :action => 'boo' })
+    get URI("http://test.host/pages/show")
+    assert_equal "/page/20",   controller.url_for(id: 20, only_path: true)
+    assert_equal "/page/20",   url_for(rs, controller: "pages", id: 20, action: "show")
+    assert_equal "/pages/boo", url_for(rs, controller: "pages", action: "boo")
   end
 
   def test_route_with_integer_default
     rs.draw do
-      get 'page(/:id)' => 'content#show_page', :id => 1
+      get "page(/:id)" => "content#show_page", :id => 1
 
       ActiveSupport::Deprecation.silence do
-        get ':controller/:action/:id'
+        get ":controller/:action/:id"
       end
     end
 
-    assert_equal '/page',    url_for(rs, { :controller => 'content', :action => 'show_page' })
-    assert_equal '/page',    url_for(rs, { :controller => 'content', :action => 'show_page', :id => 1 })
-    assert_equal '/page',    url_for(rs, { :controller => 'content', :action => 'show_page', :id => '1' })
-    assert_equal '/page/10', url_for(rs, { :controller => 'content', :action => 'show_page', :id => 10 })
+    assert_equal "/page",    url_for(rs, controller: "content", action: "show_page")
+    assert_equal "/page",    url_for(rs, controller: "content", action: "show_page", id: 1)
+    assert_equal "/page",    url_for(rs, controller: "content", action: "show_page", id: "1")
+    assert_equal "/page/10", url_for(rs, controller: "content", action: "show_page", id: 10)
 
-    assert_equal({:controller => "content", :action => 'show_page', :id => 1 }, rs.recognize_path("/page"))
-    assert_equal({:controller => "content", :action => 'show_page', :id => '1'}, rs.recognize_path("/page/1"))
-    assert_equal({:controller => "content", :action => 'show_page', :id => '10'}, rs.recognize_path("/page/10"))
+    assert_equal({ controller: "content", action: "show_page", id: 1 }, rs.recognize_path("/page"))
+    assert_equal({ controller: "content", action: "show_page", id: "1" }, rs.recognize_path("/page/1"))
+    assert_equal({ controller: "content", action: "show_page", id: "10" }, rs.recognize_path("/page/10"))
   end
 
   # For newer revision
   def test_route_with_text_default
     rs.draw do
-      get 'page/:id' => 'content#show_page', :id => 1
+      get "page/:id" => "content#show_page", :id => 1
 
       ActiveSupport::Deprecation.silence do
-        get ':controller/:action/:id'
+        get ":controller/:action/:id"
       end
     end
 
-    assert_equal '/page/foo', url_for(rs, { :controller => 'content', :action => 'show_page', :id => 'foo' })
-    assert_equal({ :controller => "content", :action => 'show_page', :id => 'foo' }, rs.recognize_path("/page/foo"))
+    assert_equal "/page/foo", url_for(rs, controller: "content", action: "show_page", id: "foo")
+    assert_equal({ controller: "content", action: "show_page", id: "foo" }, rs.recognize_path("/page/foo"))
 
-    token = "\321\202\320\265\320\272\321\201\321\202" # 'text' in Russian
+    token = "\321\202\320\265\320\272\321\201\321\202".dup # 'text' in Russian
     token.force_encoding(Encoding::BINARY)
     escaped_token = CGI::escape(token)
 
-    assert_equal '/page/' + escaped_token, url_for(rs, { :controller => 'content', :action => 'show_page', :id => token })
-    assert_equal({ :controller => "content", :action => 'show_page', :id => token }, rs.recognize_path("/page/#{escaped_token}"))
+    assert_equal "/page/" + escaped_token, url_for(rs, controller: "content", action: "show_page", id: token)
+    assert_equal({ controller: "content", action: "show_page", id: token }, rs.recognize_path("/page/#{escaped_token}"))
   end
 
   def test_action_expiry
-    rs.draw { ActiveSupport::Deprecation.silence { get ':controller(/:action(/:id))' } }
-    get URI('http://test.host/content/show')
-    assert_equal '/content', controller.url_for(:controller => 'content', :only_path => true)
+    rs.draw { ActiveSupport::Deprecation.silence { get ":controller(/:action(/:id))" } }
+    get URI("http://test.host/content/show")
+    assert_equal "/content", controller.url_for(controller: "content", only_path: true)
   end
 
   def test_requirement_should_prevent_optional_id
     rs.draw do
-      get 'post/:id' => 'post#show', :constraints => {:id => /\d+/}, :as => 'post'
+      get "post/:id" => "post#show", :constraints => { id: /\d+/ }, :as => "post"
     end
 
-    assert_equal '/post/10', url_for(rs, { :controller => 'post', :action => 'show', :id => 10 })
+    assert_equal "/post/10", url_for(rs, controller: "post", action: "show", id: 10)
 
     assert_raise(ActionController::UrlGenerationError) do
-      url_for(rs, { :controller => 'post', :action => 'show' })
+      url_for(rs, controller: "post", action: "show")
     end
   end
 
   def test_both_requirement_and_optional
     rs.draw do
-      get('test(/:year)' => 'post#show', :as => 'blog',
-        :defaults => { :year => nil },
-        :constraints => { :year => /\d{4}/ }
+      get("test(/:year)" => "post#show", :as => "blog",
+        :defaults => { year: nil },
+        :constraints => { year: /\d{4}/ }
       )
 
       ActiveSupport::Deprecation.silence do
-        get ':controller/:action/:id'
+        get ":controller/:action/:id"
       end
     end
 
-    assert_equal '/test', url_for(rs, { :controller => 'post', :action => 'show' })
-    assert_equal '/test', url_for(rs, { :controller => 'post', :action => 'show', :year => nil })
+    assert_equal "/test", url_for(rs, controller: "post", action: "show")
+    assert_equal "/test", url_for(rs, controller: "post", action: "show", year: nil)
 
     assert_equal("http://test.host/test", setup_for_named_route.send(:blog_url))
   end
 
   def test_set_to_nil_forgets
     rs.draw do
-      get 'pages(/:year(/:month(/:day)))' => 'content#list_pages', :month => nil, :day => nil
+      get "pages(/:year(/:month(/:day)))" => "content#list_pages", :month => nil, :day => nil
 
       ActiveSupport::Deprecation.silence do
-        get ':controller/:action/:id'
+        get ":controller/:action/:id"
       end
     end
 
-    assert_equal '/pages/2005',
-      url_for(rs, { :controller => 'content', :action => 'list_pages', :year => 2005 })
-    assert_equal '/pages/2005/6',
-      url_for(rs, { :controller => 'content', :action => 'list_pages', :year => 2005, :month => 6 })
-    assert_equal '/pages/2005/6/12',
-      url_for(rs, { :controller => 'content', :action => 'list_pages', :year => 2005, :month => 6, :day => 12 })
+    assert_equal "/pages/2005",
+      url_for(rs, controller: "content", action: "list_pages", year: 2005)
+    assert_equal "/pages/2005/6",
+      url_for(rs, controller: "content", action: "list_pages", year: 2005, month: 6)
+    assert_equal "/pages/2005/6/12",
+      url_for(rs, controller: "content", action: "list_pages", year: 2005, month: 6, day: 12)
 
-    get URI('http://test.host/pages/2005/6/12')
-    assert_equal({ :controller => 'content', :action => 'list_pages', :year => '2005', :month => '6', :day => '12' },
+    get URI("http://test.host/pages/2005/6/12")
+    assert_equal({ controller: "content", action: "list_pages", year: "2005", month: "6", day: "12" },
                 controller.request.path_parameters)
 
-    assert_equal '/pages/2005/6/4',
-      controller.url_for({ :day => 4, :only_path => true })
+    assert_equal "/pages/2005/6/4",
+      controller.url_for(day: 4, only_path: true)
 
-    assert_equal '/pages/2005/6',
-      controller.url_for({ :day => nil, :only_path => true })
+    assert_equal "/pages/2005/6",
+      controller.url_for(day: nil, only_path: true)
 
-    assert_equal '/pages/2005',
-      controller.url_for({ :day => nil, :month => nil, :only_path => true })
+    assert_equal "/pages/2005",
+      controller.url_for(day: nil, month: nil, only_path: true)
   end
 
   def test_root_url_generation_with_controller_and_action
     rs.draw do
-      root :to => "content#index"
+      root to: "content#index"
     end
 
-    assert_equal '/', url_for(rs, { :controller => 'content', :action => 'index' })
-    assert_equal '/', url_for(rs, { :controller => 'content' })
+    assert_equal "/", url_for(rs, controller: "content", action: "index")
+    assert_equal "/", url_for(rs, controller: "content")
   end
 
   def test_named_root_url_generation_with_controller_and_action
     rs.draw do
-       root :to => "content#index", :as => 'home'
+      root to: "content#index", as: "home"
     end
 
-    assert_equal '/', url_for(rs, { :controller => 'content', :action => 'index' })
-    assert_equal '/', url_for(rs, { :controller => 'content' })
+    assert_equal "/", url_for(rs, controller: "content", action: "index")
+    assert_equal "/", url_for(rs, controller: "content")
 
     assert_equal("http://test.host/", setup_for_named_route.send(:home_url))
   end
 
   def test_named_route_method
     rs.draw do
-      get 'categories' => 'content#categories', :as => 'categories'
+      get "categories" => "content#categories", :as => "categories"
 
       ActiveSupport::Deprecation.silence do
-        get ':controller(/:action(/:id))'
+        get ":controller(/:action(/:id))"
       end
     end
 
-    assert_equal '/categories', url_for(rs, { :controller => 'content', :action => 'categories' })
-    assert_equal '/content/hi', url_for(rs, { :controller => 'content', :action => 'hi' })
+    assert_equal "/categories", url_for(rs, controller: "content", action: "categories")
+    assert_equal "/content/hi", url_for(rs, controller: "content", action: "hi")
   end
 
   def test_named_routes_array
@@ -772,56 +788,55 @@ class LegacyRouteSetTests < ActiveSupport::TestCase
 
   def test_nil_defaults
     rs.draw do
-      get 'journal' => 'content#list_journal',
+      get "journal" => "content#list_journal",
         :date => nil, :user_id => nil
 
       ActiveSupport::Deprecation.silence do
-        get ':controller/:action/:id'
+        get ":controller/:action/:id"
       end
     end
 
-    assert_equal '/journal', url_for(rs, {
-      :controller => 'content',
-      :action => 'list_journal',
-      :date => nil,
-      :user_id => nil
-    })
+    assert_equal "/journal", url_for(rs,
+      controller: "content",
+      action: "list_journal",
+      date: nil,
+      user_id: nil)
   end
 
   def setup_request_method_routes_for(method)
     rs.draw do
-      match '/match' => "books##{method}", :via => method.to_sym
+      match "/match" => "books##{method}", :via => method.to_sym
     end
   end
 
   %w(GET PATCH POST PUT DELETE).each do |request_method|
     define_method("test_request_method_recognized_with_#{request_method}") do
       setup_request_method_routes_for(request_method.downcase)
-      params = rs.recognize_path("/match", :method => request_method)
+      params = rs.recognize_path("/match", method: request_method)
       assert_equal request_method.downcase, params[:action]
     end
   end
 
   def test_recognize_array_of_methods
     rs.draw do
-      match '/match' => 'books#get_or_post', :via => [:get, :post]
-      put '/match' => 'books#not_get_or_post'
+      match "/match" => "books#get_or_post", :via => [:get, :post]
+      put "/match" => "books#not_get_or_post"
     end
 
-    params = rs.recognize_path("/match", :method => :post)
-    assert_equal 'get_or_post', params[:action]
+    params = rs.recognize_path("/match", method: :post)
+    assert_equal "get_or_post", params[:action]
 
-    params = rs.recognize_path("/match", :method => :put)
-    assert_equal 'not_get_or_post', params[:action]
+    params = rs.recognize_path("/match", method: :put)
+    assert_equal "not_get_or_post", params[:action]
   end
 
   def test_subpath_recognized
     rs.draw do
       ActiveSupport::Deprecation.silence do
-        get '/books/:id/edit'    => 'subpath_books#edit'
-        get '/items/:id/:action' => 'subpath_books'
-        get '/posts/new/:action' => 'subpath_books'
-        get '/posts/:id'         => 'subpath_books#show'
+        get "/books/:id/edit"    => "subpath_books#edit"
+        get "/items/:id/:action" => "subpath_books"
+        get "/posts/new/:action" => "subpath_books"
+        get "/posts/:id"         => "subpath_books#show"
       end
     end
 
@@ -845,20 +860,20 @@ class LegacyRouteSetTests < ActiveSupport::TestCase
   def test_subpath_generated
     rs.draw do
       ActiveSupport::Deprecation.silence do
-        get '/books/:id/edit'    => 'subpath_books#edit'
-        get '/items/:id/:action' => 'subpath_books'
-        get '/posts/new/:action' => 'subpath_books'
+        get "/books/:id/edit"    => "subpath_books#edit"
+        get "/items/:id/:action" => "subpath_books"
+        get "/posts/new/:action" => "subpath_books"
       end
     end
 
-    assert_equal "/books/7/edit",      url_for(rs, { :controller => "subpath_books", :id => 7, :action => "edit" })
-    assert_equal "/items/15/complete", url_for(rs, { :controller => "subpath_books", :id => 15, :action => "complete" })
-    assert_equal "/posts/new/preview", url_for(rs, { :controller => "subpath_books", :action => "preview" })
+    assert_equal "/books/7/edit",      url_for(rs, controller: "subpath_books", id: 7, action: "edit")
+    assert_equal "/items/15/complete", url_for(rs, controller: "subpath_books", id: 15, action: "complete")
+    assert_equal "/posts/new/preview", url_for(rs, controller: "subpath_books", action: "preview")
   end
 
   def test_failed_constraints_raises_exception_with_violated_constraints
     rs.draw do
-      get 'foos/:id' => 'foos#show', :as => 'foo_with_requirement', :constraints => { :id => /\d+/ }
+      get "foos/:id" => "foos#show", :as => "foo_with_requirement", :constraints => { id: /\d+/ }
     end
 
     assert_raise(ActionController::UrlGenerationError) do
@@ -869,13 +884,13 @@ class LegacyRouteSetTests < ActiveSupport::TestCase
   def test_routes_changed_correctly_after_clear
     rs = ::ActionDispatch::Routing::RouteSet.new
     rs.draw do
-      get 'ca' => 'ca#aa'
-      get 'cb' => 'cb#ab'
-      get 'cc' => 'cc#ac'
+      get "ca" => "ca#aa"
+      get "cb" => "cb#ab"
+      get "cc" => "cc#ac"
 
       ActiveSupport::Deprecation.silence do
-        get ':controller/:action/:id'
-        get ':controller/:action/:id.:format'
+        get ":controller/:action/:id"
+        get ":controller/:action/:id.:format"
       end
     end
 
@@ -885,12 +900,12 @@ class LegacyRouteSetTests < ActiveSupport::TestCase
     assert_equal %w(cc ac), [hash[:controller], hash[:action]]
 
     rs.draw do
-      get 'cb' => 'cb#ab'
-      get 'cc' => 'cc#ac'
+      get "cb" => "cb#ab"
+      get "cc" => "cc#ac"
 
       ActiveSupport::Deprecation.silence do
-        get ':controller/:action/:id'
-        get ':controller/:action/:id.:format'
+        get ":controller/:action/:id"
+        get ":controller/:action/:id.:format"
       end
     end
 
@@ -924,7 +939,7 @@ class RouteSetTest < ActiveSupport::TestCase
       set.draw do
 
         ActiveSupport::Deprecation.silence do
-          get '/:controller(/:action(/:id))'
+          get "/:controller(/:action(/:id))"
         end
       end
       set
@@ -932,26 +947,26 @@ class RouteSetTest < ActiveSupport::TestCase
   end
 
   def test_generate_extras
-    set.draw { ActiveSupport::Deprecation.silence { get ':controller/(:action(/:id))' } }
-    path, extras = set.generate_extras(:controller => "foo", :action => "bar", :id => 15, :this => "hello", :that => "world")
+    set.draw { ActiveSupport::Deprecation.silence { get ":controller/(:action(/:id))" } }
+    path, extras = set.generate_extras(controller: "foo", action: "bar", id: 15, this: "hello", that: "world")
     assert_equal "/foo/bar/15", path
     assert_equal %w(that this), extras.map(&:to_s).sort
   end
 
   def test_extra_keys
-    set.draw { ActiveSupport::Deprecation.silence { get ':controller/:action/:id' } }
-    extras = set.extra_keys(:controller => "foo", :action => "bar", :id => 15, :this => "hello", :that => "world")
+    set.draw { ActiveSupport::Deprecation.silence { get ":controller/:action/:id" } }
+    extras = set.extra_keys(controller: "foo", action: "bar", id: 15, this: "hello", that: "world")
     assert_equal %w(that this), extras.map(&:to_s).sort
   end
 
   def test_generate_extras_not_first
     set.draw do
       ActiveSupport::Deprecation.silence do
-        get ':controller/:action/:id.:format'
-        get ':controller/:action/:id'
+        get ":controller/:action/:id.:format"
+        get ":controller/:action/:id"
       end
     end
-    path, extras = set.generate_extras(:controller => "foo", :action => "bar", :id => 15, :this => "hello", :that => "world")
+    path, extras = set.generate_extras(controller: "foo", action: "bar", id: 15, this: "hello", that: "world")
     assert_equal "/foo/bar/15", path
     assert_equal %w(that this), extras.map(&:to_s).sort
   end
@@ -959,29 +974,29 @@ class RouteSetTest < ActiveSupport::TestCase
   def test_generate_not_first
     set.draw do
       ActiveSupport::Deprecation.silence do
-        get ':controller/:action/:id.:format'
-        get ':controller/:action/:id'
+        get ":controller/:action/:id.:format"
+        get ":controller/:action/:id"
       end
     end
     assert_equal "/foo/bar/15?this=hello",
-        url_for(set, { :controller => "foo", :action => "bar", :id => 15, :this => "hello" })
+        url_for(set, controller: "foo", action: "bar", id: 15, this: "hello")
   end
 
   def test_extra_keys_not_first
     set.draw do
       ActiveSupport::Deprecation.silence do
-        get ':controller/:action/:id.:format'
-        get ':controller/:action/:id'
+        get ":controller/:action/:id.:format"
+        get ":controller/:action/:id"
       end
     end
-    extras = set.extra_keys(:controller => "foo", :action => "bar", :id => 15, :this => "hello", :that => "world")
+    extras = set.extra_keys(controller: "foo", action: "bar", id: 15, this: "hello", that: "world")
     assert_equal %w(that this), extras.map(&:to_s).sort
   end
 
   def test_draw
     assert_equal 0, set.routes.size
     set.draw do
-      get '/hello/world' => 'a#b'
+      get "/hello/world" => "a#b"
     end
     assert_equal 1, set.routes.size
   end
@@ -989,16 +1004,16 @@ class RouteSetTest < ActiveSupport::TestCase
   def test_draw_symbol_controller_name
     assert_equal 0, set.routes.size
     set.draw do
-      get '/users/index' => 'users#index'
+      get "/users/index" => "users#index"
     end
-    set.recognize_path('/users/index', :method => :get)
+    set.recognize_path("/users/index", method: :get)
     assert_equal 1, set.routes.size
   end
 
   def test_named_draw
     assert_equal 0, set.routes.size
     set.draw do
-      get '/hello/world' => 'a#b', :as => 'hello'
+      get "/hello/world" => "a#b", :as => "hello"
     end
     assert_equal 1, set.routes.size
     assert_equal set.routes.first, set.named_routes[:hello]
@@ -1007,57 +1022,57 @@ class RouteSetTest < ActiveSupport::TestCase
   def test_duplicate_named_route_raises_rather_than_pick_precedence
     assert_raise ArgumentError do
       set.draw do
-        get '/hello/world' => 'a#b', :as => 'hello'
-        get '/hello'       => 'a#b', :as => 'hello'
+        get "/hello/world" => "a#b", :as => "hello"
+        get "/hello"       => "a#b", :as => "hello"
       end
     end
   end
 
   def setup_named_route_test
     set.draw do
-      get '/people(/:id)' => 'people#show', :as => 'show'
-      get '/people' => 'people#index', :as => 'index'
-      get '/people/go/:foo/:bar/joe(/:id)' => 'people#multi', :as => 'multi'
-      get '/admin/users' => 'admin/users#index', :as => "users"
+      get "/people(/:id)" => "people#show", :as => "show"
+      get "/people" => "people#index", :as => "index"
+      get "/people/go/:foo/:bar/joe(/:id)" => "people#multi", :as => "multi"
+      get "/admin/users" => "admin/users#index", :as => "users"
     end
 
-    get URI('http://test.host/people')
+    get URI("http://test.host/people")
     controller
   end
 
   def test_named_route_url_method
     controller = setup_named_route_test
 
-    assert_equal "http://test.host/people/5", controller.send(:show_url, :id => 5)
-    assert_equal "/people/5", controller.send(:show_path, :id => 5)
+    assert_equal "http://test.host/people/5", controller.send(:show_url, id: 5)
+    assert_equal "/people/5", controller.send(:show_path, id: 5)
 
     assert_equal "http://test.host/people", controller.send(:index_url)
     assert_equal "/people", controller.send(:index_path)
 
     assert_equal "http://test.host/admin/users", controller.send(:users_url)
-    assert_equal '/admin/users', controller.send(:users_path)
+    assert_equal "/admin/users", controller.send(:users_path)
   end
 
   def test_named_route_url_method_with_anchor
     controller = setup_named_route_test
 
-    assert_equal "http://test.host/people/5#location", controller.send(:show_url, :id => 5, :anchor => 'location')
-    assert_equal "/people/5#location", controller.send(:show_path, :id => 5, :anchor => 'location')
+    assert_equal "http://test.host/people/5#location", controller.send(:show_url, id: 5, anchor: "location")
+    assert_equal "/people/5#location", controller.send(:show_path, id: 5, anchor: "location")
 
-    assert_equal "http://test.host/people#location", controller.send(:index_url, :anchor => 'location')
-    assert_equal "/people#location", controller.send(:index_path, :anchor => 'location')
+    assert_equal "http://test.host/people#location", controller.send(:index_url, anchor: "location")
+    assert_equal "/people#location", controller.send(:index_path, anchor: "location")
 
-    assert_equal "http://test.host/admin/users#location", controller.send(:users_url, :anchor => 'location')
-    assert_equal '/admin/users#location', controller.send(:users_path, :anchor => 'location')
+    assert_equal "http://test.host/admin/users#location", controller.send(:users_url, anchor: "location")
+    assert_equal "/admin/users#location", controller.send(:users_path, anchor: "location")
 
     assert_equal "http://test.host/people/go/7/hello/joe/5#location",
-      controller.send(:multi_url, 7, "hello", 5, :anchor => 'location')
+      controller.send(:multi_url, 7, "hello", 5, anchor: "location")
 
     assert_equal "http://test.host/people/go/7/hello/joe/5?baz=bar#location",
-      controller.send(:multi_url, 7, "hello", 5, :baz => "bar", :anchor => 'location')
+      controller.send(:multi_url, 7, "hello", 5, baz: "bar", anchor: "location")
 
     assert_equal "http://test.host/people?baz=bar#location",
-      controller.send(:index_url, :baz => "bar", :anchor => 'location')
+      controller.send(:index_url, baz: "bar", anchor: "location")
 
     assert_equal "http://test.host/people", controller.send(:index_url, anchor: nil)
     assert_equal "http://test.host/people", controller.send(:index_url, anchor: false)
@@ -1065,17 +1080,17 @@ class RouteSetTest < ActiveSupport::TestCase
 
   def test_named_route_url_method_with_port
     controller = setup_named_route_test
-    assert_equal "http://test.host:8080/people/5", controller.send(:show_url, 5, :port=>8080)
+    assert_equal "http://test.host:8080/people/5", controller.send(:show_url, 5, port: 8080)
   end
 
   def test_named_route_url_method_with_host
     controller = setup_named_route_test
-    assert_equal "http://some.example.com/people/5", controller.send(:show_url, 5, :host=>"some.example.com")
+    assert_equal "http://some.example.com/people/5", controller.send(:show_url, 5, host: "some.example.com")
   end
 
   def test_named_route_url_method_with_protocol
     controller = setup_named_route_test
-    assert_equal "https://test.host/people/5", controller.send(:show_url, 5, :protocol => "https")
+    assert_equal "https://test.host/people/5", controller.send(:show_url, 5, protocol: "https")
   end
 
   def test_named_route_url_method_with_ordered_parameters
@@ -1087,7 +1102,7 @@ class RouteSetTest < ActiveSupport::TestCase
   def test_named_route_url_method_with_ordered_parameters_and_hash
     controller = setup_named_route_test
     assert_equal "http://test.host/people/go/7/hello/joe/5?baz=bar",
-      controller.send(:multi_url, 7, "hello", 5, :baz => "bar")
+      controller.send(:multi_url, 7, "hello", 5, baz: "bar")
   end
 
   def test_named_route_url_method_with_ordered_parameters_and_empty_hash
@@ -1099,46 +1114,46 @@ class RouteSetTest < ActiveSupport::TestCase
   def test_named_route_url_method_with_no_positional_arguments
     controller = setup_named_route_test
     assert_equal "http://test.host/people?baz=bar",
-      controller.send(:index_url, :baz => "bar")
+      controller.send(:index_url, baz: "bar")
   end
 
   def test_draw_default_route
     set.draw do
       ActiveSupport::Deprecation.silence do
-        get ':controller/:action/:id'
+        get ":controller/:action/:id"
       end
     end
 
     assert_equal 1, set.routes.size
 
-    assert_equal '/users/show/10',  url_for(set, { :controller => 'users', :action => 'show', :id => 10 })
-    assert_equal '/users/index/10', url_for(set, { :controller => 'users', :id => 10 })
+    assert_equal "/users/show/10",  url_for(set, controller: "users", action: "show", id: 10)
+    assert_equal "/users/index/10", url_for(set, controller: "users", id: 10)
 
-    assert_equal({:controller => 'users', :action => 'index', :id => '10'}, set.recognize_path('/users/index/10'))
-    assert_equal({:controller => 'users', :action => 'index', :id => '10'}, set.recognize_path('/users/index/10/'))
+    assert_equal({ controller: "users", action: "index", id: "10" }, set.recognize_path("/users/index/10"))
+    assert_equal({ controller: "users", action: "index", id: "10" }, set.recognize_path("/users/index/10/"))
   end
 
   def test_route_with_parameter_shell
     set.draw do
-      get 'page/:id' => 'pages#show', :id => /\d+/
+      get "page/:id" => "pages#show", :id => /\d+/
 
       ActiveSupport::Deprecation.silence do
-        get '/:controller(/:action(/:id))'
+        get "/:controller(/:action(/:id))"
       end
     end
 
-    assert_equal({:controller => 'pages', :action => 'index'}, request_path_params('/pages'))
-    assert_equal({:controller => 'pages', :action => 'index'}, request_path_params('/pages/index'))
-    assert_equal({:controller => 'pages', :action => 'list'}, request_path_params('/pages/list'))
+    assert_equal({ controller: "pages", action: "index" }, request_path_params("/pages"))
+    assert_equal({ controller: "pages", action: "index" }, request_path_params("/pages/index"))
+    assert_equal({ controller: "pages", action: "list" }, request_path_params("/pages/list"))
 
-    assert_equal({:controller => 'pages', :action => 'show', :id => '10'}, request_path_params('/pages/show/10'))
-    assert_equal({:controller => 'pages', :action => 'show', :id => '10'}, request_path_params('/page/10'))
+    assert_equal({ controller: "pages", action: "show", id: "10" }, request_path_params("/pages/show/10"))
+    assert_equal({ controller: "pages", action: "show", id: "10" }, request_path_params("/page/10"))
   end
 
   def test_route_constraints_on_request_object_with_anchors_are_valid
     assert_nothing_raised do
       set.draw do
-        get 'page/:id' => 'pages#show', :constraints => { :host => /^foo$/ }
+        get "page/:id" => "pages#show", :constraints => { host: /^foo$/ }
       end
     end
   end
@@ -1146,27 +1161,27 @@ class RouteSetTest < ActiveSupport::TestCase
   def test_route_constraints_with_anchor_chars_are_invalid
     assert_raise ArgumentError do
       set.draw do
-        get 'page/:id' => 'pages#show', :id => /^\d+/
+        get "page/:id" => "pages#show", :id => /^\d+/
       end
     end
     assert_raise ArgumentError do
       set.draw do
-        get 'page/:id' => 'pages#show', :id => /\A\d+/
+        get "page/:id" => "pages#show", :id => /\A\d+/
       end
     end
     assert_raise ArgumentError do
       set.draw do
-        get 'page/:id' => 'pages#show', :id => /\d+$/
+        get "page/:id" => "pages#show", :id => /\d+$/
       end
     end
     assert_raise ArgumentError do
       set.draw do
-        get 'page/:id' => 'pages#show', :id => /\d+\Z/
+        get "page/:id" => "pages#show", :id => /\d+\Z/
       end
     end
     assert_raise ArgumentError do
       set.draw do
-        get 'page/:id' => 'pages#show', :id => /\d+\z/
+        get "page/:id" => "pages#show", :id => /\d+\z/
       end
     end
   end
@@ -1174,7 +1189,7 @@ class RouteSetTest < ActiveSupport::TestCase
   def test_route_constraints_with_options_method_condition_is_valid
     assert_nothing_raised do
       set.draw do
-        match 'valid/route' => 'pages#show', :via => :options
+        match "valid/route" => "pages#show", :via => :options
       end
     end
   end
@@ -1184,16 +1199,16 @@ class RouteSetTest < ActiveSupport::TestCase
       get    "/people" => "missing#index"
     end
 
-    assert_raises(ActionController::RoutingError) { request_path_params '/people' }
+    assert_raises(ActionController::RoutingError) { request_path_params "/people" }
   end
 
   def test_recognize_with_encoded_id_and_regex
     set.draw do
-      get 'page/:id' => 'pages#show', :id => /[a-zA-Z0-9\+]+/
+      get "page/:id" => "pages#show", :id => /[a-zA-Z0-9\+]+/
     end
 
-    assert_equal({:controller => 'pages', :action => 'show', :id => '10'}, request_path_params('/page/10'))
-    assert_equal({:controller => 'pages', :action => 'show', :id => 'hello+world'}, request_path_params('/page/hello+world'))
+    assert_equal({ controller: "pages", action: "show", id: "10" }, request_path_params("/page/10"))
+    assert_equal({ controller: "pages", action: "show", id: "hello+world" }, request_path_params("/page/hello+world"))
   end
 
   def test_recognize_with_http_methods
@@ -1206,65 +1221,65 @@ class RouteSetTest < ActiveSupport::TestCase
       delete "/people/:id" => "people#destroy"
     end
 
-    params = request_path_params("/people", :method => :get)
+    params = request_path_params("/people", method: :get)
     assert_equal("index", params[:action])
 
-    params = request_path_params("/people", :method => :post)
+    params = request_path_params("/people", method: :post)
     assert_equal("create", params[:action])
 
-    params = request_path_params("/people/5", :method => :put)
+    params = request_path_params("/people/5", method: :put)
     assert_equal("update", params[:action])
 
-    params = request_path_params("/people/5", :method => :patch)
+    params = request_path_params("/people/5", method: :patch)
     assert_equal("update", params[:action])
 
     assert_raise(ActionController::UnknownHttpMethod) {
-      request_path_params("/people", :method => :bacon)
+      request_path_params("/people", method: :bacon)
     }
 
-    params = request_path_params("/people/5", :method => :get)
+    params = request_path_params("/people/5", method: :get)
     assert_equal("show", params[:action])
     assert_equal("5", params[:id])
 
-    params = request_path_params("/people/5", :method => :put)
+    params = request_path_params("/people/5", method: :put)
     assert_equal("update", params[:action])
     assert_equal("5", params[:id])
 
-    params = request_path_params("/people/5", :method => :patch)
+    params = request_path_params("/people/5", method: :patch)
     assert_equal("update", params[:action])
     assert_equal("5", params[:id])
 
-    params = request_path_params("/people/5", :method => :delete)
+    params = request_path_params("/people/5", method: :delete)
     assert_equal("destroy", params[:action])
     assert_equal("5", params[:id])
 
     assert_raise(ActionController::RoutingError) {
-      request_path_params("/people/5", :method => :post)
+      request_path_params("/people/5", method: :post)
     }
   end
 
   def test_recognize_with_alias_in_conditions
     set.draw do
-      match "/people" => 'people#index', :as => 'people', :via => :get
-      root :to => "people#index"
+      match "/people" => "people#index", :as => "people", :via => :get
+      root to: "people#index"
     end
 
-    params = request_path_params("/people", :method => :get)
+    params = request_path_params("/people", method: :get)
     assert_equal("people", params[:controller])
     assert_equal("index", params[:action])
 
-    params = request_path_params("/", :method => :get)
+    params = request_path_params("/", method: :get)
     assert_equal("people", params[:controller])
     assert_equal("index", params[:action])
   end
 
   def test_typo_recognition
     set.draw do
-      get 'articles/:year/:month/:day/:title' => 'articles#permalink',
+      get "articles/:year/:month/:day/:title" => "articles#permalink",
              :year => /\d{4}/, :day => /\d{1,2}/, :month => /\d{1,2}/
     end
 
-    params = request_path_params("/articles/2005/11/05/a-very-interesting-article", :method => :get)
+    params = request_path_params("/articles/2005/11/05/a-very-interesting-article", method: :get)
     assert_equal("permalink", params[:action])
     assert_equal("2005", params[:year])
     assert_equal("11", params[:month])
@@ -1275,7 +1290,7 @@ class RouteSetTest < ActiveSupport::TestCase
   def test_routing_traversal_does_not_load_extra_classes
     assert !Object.const_defined?("Profiler__"), "Profiler should not be loaded"
     set.draw do
-      get '/profile' => 'profile#index'
+      get "/profile" => "profile#index"
     end
 
     request_path_params("/profile") rescue nil
@@ -1291,17 +1306,17 @@ class RouteSetTest < ActiveSupport::TestCase
       get "people/:id(.:format)" => "people#show"
     end
 
-    params = request_path_params("/people/5", :method => :get)
+    params = request_path_params("/people/5", method: :get)
     assert_equal("show", params[:action])
     assert_equal("5", params[:id])
 
-    params = request_path_params("/people/5", :method => :put)
+    params = request_path_params("/people/5", method: :put)
     assert_equal("update", params[:action])
 
-    params = request_path_params("/people/5", :method => :patch)
+    params = request_path_params("/people/5", method: :patch)
     assert_equal("update", params[:action])
 
-    params = request_path_params("/people/5.png", :method => :get)
+    params = request_path_params("/people/5.png", method: :get)
     assert_equal("show", params[:action])
     assert_equal("5", params[:id])
     assert_equal("png", params[:format])
@@ -1309,18 +1324,18 @@ class RouteSetTest < ActiveSupport::TestCase
 
   def test_generate_with_default_action
     set.draw do
-      get "/people", :controller => "people", :action => "index"
-      get "/people/list", :controller => "people", :action => "list"
+      get "/people", controller: "people", action: "index"
+      get "/people/list", controller: "people", action: "list"
     end
 
-    url = url_for(set, { :controller => "people", :action => "list" })
+    url = url_for(set, controller: "people", action: "list")
     assert_equal "/people/list", url
   end
 
   def test_root_map
-    set.draw { root :to => 'people#index' }
+    set.draw { root to: "people#index" }
 
-    params = request_path_params("", :method => :get)
+    params = request_path_params("", method: :get)
     assert_equal("people", params[:controller])
     assert_equal("index", params[:action])
   end
@@ -1328,49 +1343,49 @@ class RouteSetTest < ActiveSupport::TestCase
   def test_namespace
     set.draw do
 
-      namespace 'api' do
-        get 'inventory' => 'products#inventory'
+      namespace "api" do
+        get "inventory" => "products#inventory"
       end
 
     end
 
-    params = request_path_params("/api/inventory", :method => :get)
+    params = request_path_params("/api/inventory", method: :get)
     assert_equal("api/products", params[:controller])
     assert_equal("inventory", params[:action])
   end
 
   def test_namespaced_root_map
     set.draw do
-      namespace 'api' do
-        root :to => 'products#index'
+      namespace "api" do
+        root to: "products#index"
       end
     end
 
-    params = request_path_params("/api", :method => :get)
+    params = request_path_params("/api", method: :get)
     assert_equal("api/products", params[:controller])
     assert_equal("index", params[:action])
   end
 
   def test_namespace_with_path_prefix
     set.draw do
-      scope :module => "api", :path => "prefix" do
-        get 'inventory' => 'products#inventory'
+      scope module: "api", path: "prefix" do
+        get "inventory" => "products#inventory"
       end
     end
 
-    params = request_path_params("/prefix/inventory", :method => :get)
+    params = request_path_params("/prefix/inventory", method: :get)
     assert_equal("api/products", params[:controller])
     assert_equal("inventory", params[:action])
   end
 
   def test_namespace_with_blank_path_prefix
     set.draw do
-      scope :module => "api", :path => "" do
-        get 'inventory' => 'products#inventory'
+      scope module: "api", path: "" do
+        get "inventory" => "products#inventory"
       end
     end
 
-    params = request_path_params("/inventory", :method => :get)
+    params = request_path_params("/inventory", method: :get)
     assert_equal("api/products", params[:controller])
     assert_equal("inventory", params[:action])
   end
@@ -1380,37 +1395,37 @@ class RouteSetTest < ActiveSupport::TestCase
 
     set.draw do
       ActiveSupport::Deprecation.silence do
-        get ':controller/:id/:action'
+        get ":controller/:id/:action"
       end
     end
 
-    get URI('http://test.host/people/7/show')
+    get URI("http://test.host/people/7/show")
 
-    assert_equal "/people/7/destroy", controller.url_for(:action => 'destroy', :only_path => true)
+    assert_equal "/people/7/destroy", controller.url_for(action: "destroy", only_path: true)
   end
 
   def test_use_static_path_when_possible
     @set = make_set false
 
     set.draw do
-      get 'about' => "welcome#about"
+      get "about" => "welcome#about"
 
       ActiveSupport::Deprecation.silence do
-        get ':controller/:id/:action'
+        get ":controller/:id/:action"
       end
     end
 
-    get URI('http://test.host/welcom/get/7')
+    get URI("http://test.host/welcom/get/7")
 
-    assert_equal "/about", controller.url_for(:controller => 'welcome',
-                                              :action => 'about',
-                                              :only_path => true)
+    assert_equal "/about", controller.url_for(controller: "welcome",
+                                              action: "about",
+                                              only_path: true)
   end
 
   def test_generate
-    set.draw { ActiveSupport::Deprecation.silence { get ':controller/:action/:id' } }
+    set.draw { ActiveSupport::Deprecation.silence { get ":controller/:action/:id" } }
 
-    args = { :controller => "foo", :action => "bar", :id => "7", :x => "y" }
+    args = { controller: "foo", action: "bar", id: "7", x: "y" }
     assert_equal "/foo/bar/7?x=y",     url_for(set, args)
     assert_equal ["/foo/bar/7", [:x]], set.generate_extras(args)
     assert_equal [:x], set.extra_keys(args)
@@ -1420,12 +1435,12 @@ class RouteSetTest < ActiveSupport::TestCase
     set.draw do
       scope "my" do
         ActiveSupport::Deprecation.silence do
-          get ':controller(/:action(/:id))'
+          get ":controller(/:action(/:id))"
         end
       end
     end
 
-    args = { :controller => "foo", :action => "bar", :id => "7", :x => "y" }
+    args = { controller: "foo", action: "bar", id: "7", x: "y" }
     assert_equal "/my/foo/bar/7?x=y", url_for(set, args)
   end
 
@@ -1433,12 +1448,12 @@ class RouteSetTest < ActiveSupport::TestCase
     set.draw do
       scope "" do
         ActiveSupport::Deprecation.silence do
-          get ':controller(/:action(/:id))'
+          get ":controller(/:action(/:id))"
         end
       end
     end
 
-    args = { :controller => "foo", :action => "bar", :id => "7", :x => "y" }
+    args = { controller: "foo", action: "bar", id: "7", x: "y" }
     assert_equal "/foo/bar/7?x=y", url_for(set, args)
   end
 
@@ -1447,20 +1462,20 @@ class RouteSetTest < ActiveSupport::TestCase
 
     set.draw do
       ActiveSupport::Deprecation.silence do
-        get "/connection/manage(/:action)" => 'connection/manage#index'
+        get "/connection/manage(/:action)" => "connection/manage#index"
         get "/connection/connection" => "connection/connection#index"
-        get '/connection' => 'connection#index', :as => 'family_connection'
+        get "/connection" => "connection#index", :as => "family_connection"
       end
     end
 
-    assert_equal({ :controller => 'connection/manage',
-                   :action => 'index', }, request_path_params('/connection/manage'))
+    assert_equal({ controller: "connection/manage",
+                   action: "index", }, request_path_params("/connection/manage"))
 
-    url = controller.url_for({ :controller => "connection", :only_path => true })
+    url = controller.url_for(controller: "connection", only_path: true)
     assert_equal "/connection/connection", url
 
-    url = controller.url_for({ :use_route => "family_connection",
-                               :controller => "connection", :only_path => true })
+    url = controller.url_for(use_route: "family_connection",
+                               controller: "connection", only_path: true)
     assert_equal "/connection", url
   end
 
@@ -1469,75 +1484,75 @@ class RouteSetTest < ActiveSupport::TestCase
 
     set.draw do
       ActiveSupport::Deprecation.silence do
-        get ':controller(/:action(/:id))'
+        get ":controller(/:action(/:id))"
       end
     end
 
-    get URI('http://test.host/books/show/10')
+    get URI("http://test.host/books/show/10")
 
-    assert_equal '/books', controller.url_for(:controller => 'books',
-                                              :only_path => true,
-                                              :action => 'index')
+    assert_equal "/books", controller.url_for(controller: "books",
+                                              only_path: true,
+                                              action: "index")
   end
 
   def test_query_params_will_be_shown_when_recalled
     @set = make_set false
 
     set.draw do
-      get 'show_weblog/:parameter' => 'weblog#show'
+      get "show_weblog/:parameter" => "weblog#show"
 
       ActiveSupport::Deprecation.silence do
-        get ':controller(/:action(/:id))'
+        get ":controller(/:action(/:id))"
       end
     end
 
-    get URI('http://test.host/weblog/show/1')
+    get URI("http://test.host/weblog/show/1")
 
-    assert_equal '/weblog/edit?parameter=1', controller.url_for(
-      {:action => 'edit', :parameter => 1, :only_path => true})
+    assert_equal "/weblog/edit?parameter=1", controller.url_for(
+      action: "edit", parameter: 1, only_path: true)
   end
 
   def test_format_is_not_inherit
     set.draw do
-      get '/posts(.:format)' => 'posts#index'
+      get "/posts(.:format)" => "posts#index"
     end
 
-    get URI('http://test.host/posts.xml')
-    assert_equal({:controller => 'posts', :action => 'index', :format => 'xml'},
+    get URI("http://test.host/posts.xml")
+    assert_equal({ controller: "posts", action: "index", format: "xml" },
                  controller.request.path_parameters)
 
-    assert_equal '/posts', controller.url_for(
-      {:controller => 'posts', :only_path => true})
+    assert_equal "/posts", controller.url_for(
+      controller: "posts", only_path: true)
 
-    assert_equal '/posts.xml', controller.url_for(
-      {:controller => 'posts', :format => 'xml', :only_path => true})
+    assert_equal "/posts.xml", controller.url_for(
+      controller: "posts", format: "xml", only_path: true)
   end
 
   def test_expiry_determination_should_consider_values_with_to_param
     @set = make_set false
 
-    set.draw { ActiveSupport::Deprecation.silence { get 'projects/:project_id/:controller/:action' } }
+    set.draw { ActiveSupport::Deprecation.silence { get "projects/:project_id/:controller/:action" } }
 
-    get URI('http://test.host/projects/1/weblog/show')
+    get URI("http://test.host/projects/1/weblog/show")
 
     assert_equal(
-      { :controller => 'weblog', :action => 'show', :project_id => '1' },
+      { controller: "weblog", action: "show", project_id: "1" },
       controller.request.path_parameters)
 
-    assert_equal '/projects/1/weblog/show',
-      controller.url_for({ :action => 'show', :project_id => 1, :only_path => true })
+    assert_equal "/projects/1/weblog/show",
+      controller.url_for(action: "show", project_id: 1, only_path: true)
   end
 
   def test_named_route_in_nested_resource
     set.draw do
       resources :projects do
         member do
-          get 'milestones' => 'milestones#index', :as => 'milestones'
+          get "milestones" => "milestones#index", :as => "milestones"
         end
       end
     end
 
-    params = set.recognize_path("/projects/1/milestones", :method => :get)
+    params = set.recognize_path("/projects/1/milestones", method: :get)
     assert_equal("milestones", params[:controller])
     assert_equal("index", params[:action])
   end
@@ -1546,7 +1561,7 @@ class RouteSetTest < ActiveSupport::TestCase
     assert_nothing_raised do
       set.draw do
         namespace :admin do
-          root :to => "home#index"
+          root to: "home#index"
         end
       end
     end
@@ -1555,8 +1570,8 @@ class RouteSetTest < ActiveSupport::TestCase
   def test_setting_root_in_namespace_using_string
     assert_nothing_raised do
       set.draw do
-        namespace 'admin' do
-          root :to => "home#index"
+        namespace "admin" do
+          root to: "home#index"
         end
       end
     end
@@ -1565,8 +1580,8 @@ class RouteSetTest < ActiveSupport::TestCase
   def test_route_constraints_with_unsupported_regexp_options_must_error
     assert_raise ArgumentError do
       set.draw do
-        get 'page/:name' => 'pages#show',
-          :constraints => { :name => /(david|jamis)/m }
+        get "page/:name" => "pages#show",
+          :constraints => { name: /(david|jamis)/m }
       end
     end
   end
@@ -1574,14 +1589,14 @@ class RouteSetTest < ActiveSupport::TestCase
   def test_route_constraints_with_supported_options_must_not_error
     assert_nothing_raised do
       set.draw do
-        get 'page/:name' => 'pages#show',
-          :constraints => { :name => /(david|jamis)/i }
+        get "page/:name" => "pages#show",
+          :constraints => { name: /(david|jamis)/i }
       end
     end
     assert_nothing_raised do
       set.draw do
-        get 'page/:name' => 'pages#show',
-          :constraints => { :name => / # Desperately overcommented regexp
+        get "page/:name" => "pages#show",
+          :constraints => { name: / # Desperately overcommented regexp
                                       ( #Either
                                        david #The Creator
                                       | #Or
@@ -1594,243 +1609,243 @@ class RouteSetTest < ActiveSupport::TestCase
   def test_route_with_subdomain_and_constraints_must_receive_params
     name_param = nil
     set.draw do
-      get 'page/:name' => 'pages#show', :constraints => lambda {|request|
+      get "page/:name" => "pages#show", :constraints => lambda { |request|
         name_param = request.params[:name]
         return true
       }
     end
-    assert_equal({:controller => 'pages', :action => 'show', :name => 'mypage'},
-      set.recognize_path('http://subdomain.example.org/page/mypage'))
-    assert_equal(name_param, 'mypage')
+    assert_equal({ controller: "pages", action: "show", name: "mypage" },
+      set.recognize_path("http://subdomain.example.org/page/mypage"))
+    assert_equal(name_param, "mypage")
   end
 
   def test_route_requirement_recognize_with_ignore_case
     set.draw do
-      get 'page/:name' => 'pages#show',
-        :constraints => {:name => /(david|jamis)/i}
+      get "page/:name" => "pages#show",
+        :constraints => { name: /(david|jamis)/i }
     end
-    assert_equal({:controller => 'pages', :action => 'show', :name => 'jamis'}, set.recognize_path('/page/jamis'))
+    assert_equal({ controller: "pages", action: "show", name: "jamis" }, set.recognize_path("/page/jamis"))
     assert_raise ActionController::RoutingError do
-      set.recognize_path('/page/davidjamis')
+      set.recognize_path("/page/davidjamis")
     end
-    assert_equal({:controller => 'pages', :action => 'show', :name => 'DAVID'}, set.recognize_path('/page/DAVID'))
+    assert_equal({ controller: "pages", action: "show", name: "DAVID" }, set.recognize_path("/page/DAVID"))
   end
 
   def test_route_requirement_generate_with_ignore_case
     set.draw do
-      get 'page/:name' => 'pages#show',
-        :constraints => {:name => /(david|jamis)/i}
+      get "page/:name" => "pages#show",
+        :constraints => { name: /(david|jamis)/i }
     end
 
-    url = url_for(set, { :controller => 'pages', :action => 'show', :name => 'david' })
+    url = url_for(set, controller: "pages", action: "show", name: "david")
     assert_equal "/page/david", url
     assert_raise(ActionController::UrlGenerationError) do
-      url_for(set, { :controller => 'pages', :action => 'show', :name => 'davidjamis' })
+      url_for(set, controller: "pages", action: "show", name: "davidjamis")
     end
-    url = url_for(set, { :controller => 'pages', :action => 'show', :name => 'JAMIS' })
+    url = url_for(set, controller: "pages", action: "show", name: "JAMIS")
     assert_equal "/page/JAMIS", url
   end
 
   def test_route_requirement_recognize_with_extended_syntax
     set.draw do
-      get 'page/:name' => 'pages#show',
-        :constraints => {:name => / # Desperately overcommented regexp
+      get "page/:name" => "pages#show",
+        :constraints => { name: / # Desperately overcommented regexp
                                     ( #Either
                                      david #The Creator
                                     | #Or
                                       jamis #The Deployer
-                                    )/x}
+                                    )/x }
     end
-    assert_equal({:controller => 'pages', :action => 'show', :name => 'jamis'}, set.recognize_path('/page/jamis'))
-    assert_equal({:controller => 'pages', :action => 'show', :name => 'david'}, set.recognize_path('/page/david'))
+    assert_equal({ controller: "pages", action: "show", name: "jamis" }, set.recognize_path("/page/jamis"))
+    assert_equal({ controller: "pages", action: "show", name: "david" }, set.recognize_path("/page/david"))
     assert_raise ActionController::RoutingError do
-      set.recognize_path('/page/david #The Creator')
+      set.recognize_path("/page/david #The Creator")
     end
     assert_raise ActionController::RoutingError do
-      set.recognize_path('/page/David')
+      set.recognize_path("/page/David")
     end
   end
 
   def test_route_requirement_with_xi_modifiers
     set.draw do
-      get 'page/:name' => 'pages#show',
-        :constraints => {:name => / # Desperately overcommented regexp
+      get "page/:name" => "pages#show",
+        :constraints => { name: / # Desperately overcommented regexp
                                     ( #Either
                                      david #The Creator
                                     | #Or
                                       jamis #The Deployer
-                                    )/xi}
+                                    )/xi }
     end
 
-    assert_equal({:controller => 'pages', :action => 'show', :name => 'JAMIS'},
-        set.recognize_path('/page/JAMIS'))
+    assert_equal({ controller: "pages", action: "show", name: "JAMIS" },
+        set.recognize_path("/page/JAMIS"))
 
     assert_equal "/page/JAMIS",
-        url_for(set, { :controller => 'pages', :action => 'show', :name => 'JAMIS' })
+        url_for(set, controller: "pages", action: "show", name: "JAMIS")
   end
 
   def test_routes_with_symbols
     set.draw do
-      get 'unnamed', :controller => :pages, :action => :show, :name => :as_symbol
-      get 'named'  , :controller => :pages, :action => :show, :name => :as_symbol, :as => :named
+      get "unnamed", controller: :pages, action: :show, name: :as_symbol
+      get "named", controller: :pages, action: :show, name: :as_symbol, as: :named
     end
-    assert_equal({:controller => 'pages', :action => 'show', :name => :as_symbol}, set.recognize_path('/unnamed'))
-    assert_equal({:controller => 'pages', :action => 'show', :name => :as_symbol}, set.recognize_path('/named'))
+    assert_equal({ controller: "pages", action: "show", name: :as_symbol }, set.recognize_path("/unnamed"))
+    assert_equal({ controller: "pages", action: "show", name: :as_symbol }, set.recognize_path("/named"))
   end
 
   def test_regexp_chunk_should_add_question_mark_for_optionals
     set.draw do
-      get '/' => 'foo#index'
-      get '/hello' => 'bar#index'
+      get "/" => "foo#index"
+      get "/hello" => "bar#index"
     end
 
-    assert_equal '/',      url_for(set, { :controller => 'foo' })
-    assert_equal '/hello', url_for(set, { :controller => 'bar' })
+    assert_equal "/",      url_for(set, controller: "foo")
+    assert_equal "/hello", url_for(set, controller: "bar")
 
-    assert_equal({:controller => "foo", :action => "index"}, set.recognize_path('/'))
-    assert_equal({:controller => "bar", :action => "index"}, set.recognize_path('/hello'))
+    assert_equal({ controller: "foo", action: "index" }, set.recognize_path("/"))
+    assert_equal({ controller: "bar", action: "index" }, set.recognize_path("/hello"))
   end
 
   def test_assign_route_options_with_anchor_chars
     set.draw do
       ActiveSupport::Deprecation.silence do
-        get '/cars/:action/:person/:car/', :controller => 'cars'
+        get "/cars/:action/:person/:car/", controller: "cars"
       end
     end
 
-    assert_equal '/cars/buy/1/2', url_for(set, { :controller => 'cars', :action => 'buy', :person => '1', :car => '2' })
+    assert_equal "/cars/buy/1/2", url_for(set, controller: "cars", action: "buy", person: "1", car: "2")
 
-    assert_equal({:controller => "cars", :action => "buy", :person => "1", :car => "2"}, set.recognize_path('/cars/buy/1/2'))
+    assert_equal({ controller: "cars", action: "buy", person: "1", car: "2" }, set.recognize_path("/cars/buy/1/2"))
   end
 
   def test_segmentation_of_dot_path
     set.draw do
       ActiveSupport::Deprecation.silence do
-        get '/books/:action.rss', :controller => 'books'
+        get "/books/:action.rss", controller: "books"
       end
     end
 
-    assert_equal '/books/list.rss', url_for(set, { :controller => 'books', :action => 'list' })
+    assert_equal "/books/list.rss", url_for(set, controller: "books", action: "list")
 
-    assert_equal({:controller => "books", :action => "list"}, set.recognize_path('/books/list.rss'))
+    assert_equal({ controller: "books", action: "list" }, set.recognize_path("/books/list.rss"))
   end
 
   def test_segmentation_of_dynamic_dot_path
     set.draw do
       ActiveSupport::Deprecation.silence do
-        get '/books(/:action(.:format))', :controller => 'books'
+        get "/books(/:action(.:format))", controller: "books"
       end
     end
 
-    assert_equal '/books/list.rss', url_for(set, { :controller => 'books', :action => 'list', :format => 'rss' })
-    assert_equal '/books/list.xml', url_for(set, { :controller => 'books', :action => 'list', :format => 'xml' })
-    assert_equal '/books/list',     url_for(set, { :controller => 'books', :action => 'list' })
-    assert_equal '/books',          url_for(set, { :controller => 'books', :action => 'index' })
+    assert_equal "/books/list.rss", url_for(set, controller: "books", action: "list", format: "rss")
+    assert_equal "/books/list.xml", url_for(set, controller: "books", action: "list", format: "xml")
+    assert_equal "/books/list",     url_for(set, controller: "books", action: "list")
+    assert_equal "/books",          url_for(set, controller: "books", action: "index")
 
-    assert_equal({:controller => "books", :action => "list", :format => "rss"}, set.recognize_path('/books/list.rss'))
-    assert_equal({:controller => "books", :action => "list", :format => "xml"}, set.recognize_path('/books/list.xml'))
-    assert_equal({:controller => "books", :action => "list"},  set.recognize_path('/books/list'))
-    assert_equal({:controller => "books", :action => "index"}, set.recognize_path('/books'))
+    assert_equal({ controller: "books", action: "list", format: "rss" }, set.recognize_path("/books/list.rss"))
+    assert_equal({ controller: "books", action: "list", format: "xml" }, set.recognize_path("/books/list.xml"))
+    assert_equal({ controller: "books", action: "list" },  set.recognize_path("/books/list"))
+    assert_equal({ controller: "books", action: "index" }, set.recognize_path("/books"))
   end
 
   def test_slashes_are_implied
     set.draw { ActiveSupport::Deprecation.silence { get("/:controller(/:action(/:id))") } }
 
-    assert_equal '/content',        url_for(set, { :controller => 'content', :action => 'index' })
-    assert_equal '/content/list',   url_for(set, { :controller => 'content', :action => 'list' })
-    assert_equal '/content/show/1', url_for(set, { :controller => 'content', :action => 'show', :id => '1' })
+    assert_equal "/content",        url_for(set, controller: "content", action: "index")
+    assert_equal "/content/list",   url_for(set, controller: "content", action: "list")
+    assert_equal "/content/show/1", url_for(set, controller: "content", action: "show", id: "1")
 
-    assert_equal({:controller => "content", :action => "index"}, set.recognize_path('/content'))
-    assert_equal({:controller => "content", :action => "index"}, set.recognize_path('/content/index'))
-    assert_equal({:controller => "content", :action => "list"},  set.recognize_path('/content/list'))
-    assert_equal({:controller => "content", :action => "show", :id => "1"}, set.recognize_path('/content/show/1'))
+    assert_equal({ controller: "content", action: "index" }, set.recognize_path("/content"))
+    assert_equal({ controller: "content", action: "index" }, set.recognize_path("/content/index"))
+    assert_equal({ controller: "content", action: "list" },  set.recognize_path("/content/list"))
+    assert_equal({ controller: "content", action: "show", id: "1" }, set.recognize_path("/content/show/1"))
   end
 
   def test_default_route_recognition
-    expected = {:controller => 'pages', :action => 'show', :id => '10'}
-    assert_equal expected, default_route_set.recognize_path('/pages/show/10')
-    assert_equal expected, default_route_set.recognize_path('/pages/show/10/')
+    expected = { controller: "pages", action: "show", id: "10" }
+    assert_equal expected, default_route_set.recognize_path("/pages/show/10")
+    assert_equal expected, default_route_set.recognize_path("/pages/show/10/")
 
-    expected[:id] = 'jamis'
-    assert_equal expected, default_route_set.recognize_path('/pages/show/jamis/')
+    expected[:id] = "jamis"
+    assert_equal expected, default_route_set.recognize_path("/pages/show/jamis/")
 
     expected.delete :id
-    assert_equal expected, default_route_set.recognize_path('/pages/show')
-    assert_equal expected, default_route_set.recognize_path('/pages/show/')
+    assert_equal expected, default_route_set.recognize_path("/pages/show")
+    assert_equal expected, default_route_set.recognize_path("/pages/show/")
 
-    expected[:action] = 'index'
-    assert_equal expected, default_route_set.recognize_path('/pages/')
-    assert_equal expected, default_route_set.recognize_path('/pages')
+    expected[:action] = "index"
+    assert_equal expected, default_route_set.recognize_path("/pages/")
+    assert_equal expected, default_route_set.recognize_path("/pages")
 
-    assert_raise(ActionController::RoutingError) { default_route_set.recognize_path('/') }
-    assert_raise(ActionController::RoutingError) { default_route_set.recognize_path('/pages/how/goood/it/is/to/be/free') }
+    assert_raise(ActionController::RoutingError) { default_route_set.recognize_path("/") }
+    assert_raise(ActionController::RoutingError) { default_route_set.recognize_path("/pages/how/goood/it/is/to/be/free") }
   end
 
   def test_default_route_should_omit_default_action
-    assert_equal '/accounts', url_for(default_route_set, { :controller => 'accounts', :action => 'index' })
+    assert_equal "/accounts", url_for(default_route_set, controller: "accounts", action: "index")
   end
 
   def test_default_route_should_include_default_action_when_id_present
-    assert_equal '/accounts/index/20', url_for(default_route_set, { :controller => 'accounts', :action => 'index', :id => '20' })
+    assert_equal "/accounts/index/20", url_for(default_route_set, controller: "accounts", action: "index", id: "20")
   end
 
   def test_default_route_should_work_with_action_but_no_id
-    assert_equal '/accounts/list_all', url_for(default_route_set, { :controller => 'accounts', :action => 'list_all' })
+    assert_equal "/accounts/list_all", url_for(default_route_set, controller: "accounts", action: "list_all")
   end
 
   def test_default_route_should_uri_escape_pluses
-    expected = { :controller => 'pages', :action => 'show', :id => 'hello world' }
-    assert_equal expected, default_route_set.recognize_path('/pages/show/hello%20world')
-    assert_equal '/pages/show/hello%20world', url_for(default_route_set, expected)
+    expected = { controller: "pages", action: "show", id: "hello world" }
+    assert_equal expected, default_route_set.recognize_path("/pages/show/hello%20world")
+    assert_equal "/pages/show/hello%20world", url_for(default_route_set, expected)
 
-    expected[:id] = 'hello+world'
-    assert_equal expected, default_route_set.recognize_path('/pages/show/hello+world')
-    assert_equal expected, default_route_set.recognize_path('/pages/show/hello%2Bworld')
-    assert_equal '/pages/show/hello+world', url_for(default_route_set, expected)
+    expected[:id] = "hello+world"
+    assert_equal expected, default_route_set.recognize_path("/pages/show/hello+world")
+    assert_equal expected, default_route_set.recognize_path("/pages/show/hello%2Bworld")
+    assert_equal "/pages/show/hello+world", url_for(default_route_set, expected)
   end
 
   def test_build_empty_query_string
-    assert_uri_equal '/foo', url_for(default_route_set, { :controller => 'foo' })
+    assert_uri_equal "/foo", url_for(default_route_set, controller: "foo")
   end
 
   def test_build_query_string_with_nil_value
-    assert_uri_equal '/foo', url_for(default_route_set, { :controller => 'foo', :x => nil })
+    assert_uri_equal "/foo", url_for(default_route_set, controller: "foo", x: nil)
   end
 
   def test_simple_build_query_string
-    assert_uri_equal '/foo?x=1&y=2', url_for(default_route_set, { :controller => 'foo', :x => '1', :y => '2' })
+    assert_uri_equal "/foo?x=1&y=2", url_for(default_route_set, controller: "foo", x: "1", y: "2")
   end
 
   def test_convert_ints_build_query_string
-    assert_uri_equal '/foo?x=1&y=2', url_for(default_route_set, { :controller => 'foo', :x => 1, :y => 2 })
+    assert_uri_equal "/foo?x=1&y=2", url_for(default_route_set, controller: "foo", x: 1, y: 2)
   end
 
   def test_escape_spaces_build_query_string
-    assert_uri_equal '/foo?x=hello+world&y=goodbye+world', url_for(default_route_set, { :controller => 'foo', :x => 'hello world', :y => 'goodbye world' })
+    assert_uri_equal "/foo?x=hello+world&y=goodbye+world", url_for(default_route_set, controller: "foo", x: "hello world", y: "goodbye world")
   end
 
   def test_expand_array_build_query_string
-    assert_uri_equal '/foo?x%5B%5D=1&x%5B%5D=2', url_for(default_route_set, { :controller => 'foo', :x => [1, 2] })
+    assert_uri_equal "/foo?x%5B%5D=1&x%5B%5D=2", url_for(default_route_set, controller: "foo", x: [1, 2])
   end
 
   def test_escape_spaces_build_query_string_selected_keys
-    assert_uri_equal '/foo?x=hello+world', url_for(default_route_set, { :controller => 'foo', :x => 'hello world' })
+    assert_uri_equal "/foo?x=hello+world", url_for(default_route_set, controller: "foo", x: "hello world")
   end
 
   def test_generate_with_default_params
     set.draw do
-      get 'dummy/page/:page' => 'dummy#show'
-      get 'dummy/dots/page.:page' => 'dummy#dots'
-      get 'ibocorp(/:page)' => 'ibocorp#show',
-                             :constraints => { :page => /\d+/ },
-                             :defaults => { :page => 1 }
+      get "dummy/page/:page" => "dummy#show"
+      get "dummy/dots/page.:page" => "dummy#dots"
+      get "ibocorp(/:page)" => "ibocorp#show",
+                             :constraints => { page: /\d+/ },
+                             :defaults => { page: 1 }
 
       ActiveSupport::Deprecation.silence do
-        get ':controller/:action/:id'
+        get ":controller/:action/:id"
       end
     end
 
-    assert_equal '/ibocorp', url_for(set, { :controller => 'ibocorp', :action => "show", :page => 1 })
+    assert_equal "/ibocorp", url_for(set, controller: "ibocorp", action: "show", page: 1)
   end
 
   include ActionDispatch::RoutingVerbs
@@ -1841,21 +1856,21 @@ class RouteSetTest < ActiveSupport::TestCase
     @set = make_set false
 
     set.draw do
-      get "blog/", :controller => "blog", :action => "index"
+      get "blog/", controller: "blog", action: "index"
 
       get "blog(/:year(/:month(/:day)))",
-            :controller => "blog",
-            :action => "show_date",
-            :constraints => { :year => /(19|20)\d\d/, :month => /[01]?\d/, :day => /[0-3]?\d/ },
-            :day => nil, :month => nil
+            controller: "blog",
+            action: "show_date",
+            constraints: { year: /(19|20)\d\d/, month: /[01]?\d/, day: /[0-3]?\d/ },
+            day: nil, month: nil
 
-      get "blog/show/:id", :controller => "blog", :action => "show", :id => /\d+/
+      get "blog/show/:id", controller: "blog", action: "show", id: /\d+/
 
       ActiveSupport::Deprecation.silence do
         get "blog/:controller/:action(/:id)"
       end
 
-      get "*anything", :controller => "blog", :action => "unknown_request"
+      get "*anything", controller: "blog", action: "unknown_request"
     end
 
     recognize_path = ->(path) {
@@ -1863,24 +1878,24 @@ class RouteSetTest < ActiveSupport::TestCase
       controller.request.path_parameters
     }
 
-    assert_equal({:controller => "blog", :action => "index"}, recognize_path.("/blog"))
-    assert_equal({:controller => "blog", :action => "show", :id => "123"}, recognize_path.("/blog/show/123"))
-    assert_equal({:controller => "blog", :action => "show_date", :year => "2004", :day => nil, :month => nil }, recognize_path.("/blog/2004"))
-    assert_equal({:controller => "blog", :action => "show_date", :year => "2004", :month => "12", :day => nil }, recognize_path.("/blog/2004/12"))
-    assert_equal({:controller => "blog", :action => "show_date", :year => "2004", :month => "12", :day => "25"}, recognize_path.("/blog/2004/12/25"))
-    assert_equal({:controller => "articles", :action => "edit", :id => "123"}, recognize_path.("/blog/articles/edit/123"))
-    assert_equal({:controller => "articles", :action => "show_stats"}, recognize_path.("/blog/articles/show_stats"))
-    assert_equal({:controller => "blog", :action => "unknown_request", :anything => "blog/wibble"}, recognize_path.("/blog/wibble"))
-    assert_equal({:controller => "blog", :action => "unknown_request", :anything => "junk"}, recognize_path.("/junk"))
+    assert_equal({ controller: "blog", action: "index" }, recognize_path.("/blog"))
+    assert_equal({ controller: "blog", action: "show", id: "123" }, recognize_path.("/blog/show/123"))
+    assert_equal({ controller: "blog", action: "show_date", year: "2004", day: nil, month: nil }, recognize_path.("/blog/2004"))
+    assert_equal({ controller: "blog", action: "show_date", year: "2004", month: "12", day: nil }, recognize_path.("/blog/2004/12"))
+    assert_equal({ controller: "blog", action: "show_date", year: "2004", month: "12", day: "25" }, recognize_path.("/blog/2004/12/25"))
+    assert_equal({ controller: "articles", action: "edit", id: "123" }, recognize_path.("/blog/articles/edit/123"))
+    assert_equal({ controller: "articles", action: "show_stats" }, recognize_path.("/blog/articles/show_stats"))
+    assert_equal({ controller: "blog", action: "unknown_request", anything: "blog/wibble" }, recognize_path.("/blog/wibble"))
+    assert_equal({ controller: "blog", action: "unknown_request", anything: "junk" }, recognize_path.("/junk"))
 
-    get URI('http://example.org/blog/2006/07/28')
+    get URI("http://example.org/blog/2006/07/28")
 
-    assert_equal({:controller => "blog",  :action => "show_date", :year => "2006", :month => "07", :day => "28"}, controller.request.path_parameters)
-    assert_equal("/blog/2006/07/25", controller.url_for({ :day => 25, :only_path => true }))
-    assert_equal("/blog/2005",       controller.url_for({ :year => 2005, :only_path => true }))
-    assert_equal("/blog/show/123",   controller.url_for({ :action => "show" , :id => 123, :only_path => true }))
-    assert_equal("/blog/2006",       controller.url_for({ :year => 2006, :only_path => true }))
-    assert_equal("/blog/2006",       controller.url_for({ :year => 2006, :month => nil, :only_path => true }))
+    assert_equal({ controller: "blog",  action: "show_date", year: "2006", month: "07", day: "28" }, controller.request.path_parameters)
+    assert_equal("/blog/2006/07/25", controller.url_for(day: 25, only_path: true))
+    assert_equal("/blog/2005",       controller.url_for(year: 2005, only_path: true))
+    assert_equal("/blog/show/123",   controller.url_for(action: "show", id: 123, only_path: true))
+    assert_equal("/blog/2006",       controller.url_for(year: 2006, only_path: true))
+    assert_equal("/blog/2006",       controller.url_for(year: 2006, month: nil, only_path: true))
   end
 
   private
@@ -1889,8 +1904,8 @@ class RouteSetTest < ActiveSupport::TestCase
     end
 
     def sort_query_string_params(uri)
-      path, qs = uri.split('?')
-      qs = qs.split('&').sort.join('&') if qs
+      path, qs = uri.split("?")
+      qs = qs.split("&").sort.join("&") if qs
       qs ? "#{path}?#{qs}" : path
     end
 end
@@ -1905,59 +1920,59 @@ class RackMountIntegrationTests < ActiveSupport::TestCase
       resources :users, :posts
     end
 
-    namespace 'api' do
-      root :to => 'users#index'
+    namespace "api" do
+      root to: "users#index"
     end
 
-    get '/blog(/:year(/:month(/:day)))' => 'posts#show_date',
+    get "/blog(/:year(/:month(/:day)))" => "posts#show_date",
       :constraints => {
-        :year => /(19|20)\d\d/,
-        :month => /[01]?\d/,
-        :day => /[0-3]?\d/
+        year: /(19|20)\d\d/,
+        month: /[01]?\d/,
+        day: /[0-3]?\d/
       },
       :day => nil,
       :month => nil
 
-    get 'archive/:year', :controller => 'archive', :action => 'index',
-      :defaults => { :year => nil },
-      :constraints => { :year => /\d{4}/ },
-      :as => "blog"
+    get "archive/:year", controller: "archive", action: "index",
+      defaults: { year: nil },
+      constraints: { year: /\d{4}/ },
+      as: "blog"
 
     resources :people
-    get 'legacy/people' => "people#index", :legacy => "true"
-
-    get 'symbols', :controller => :symbols, :action => :show, :name => :as_symbol
-    get 'id_default(/:id)' => "foo#id_default", :id => 1
-    match 'get_or_post' => "foo#get_or_post", :via => [:get, :post]
-    get 'optional/:optional' => "posts#index"
-    get 'projects/:project_id' => "project#index", :as => "project"
-    get 'clients' => "projects#index"
-
-    get 'ignorecase/geocode/:postalcode' => 'geocode#show', :postalcode => /hx\d\d-\d[a-z]{2}/i
-    get 'extended/geocode/:postalcode' => 'geocode#show',:constraints => {
-                  :postalcode => /# Postcode format
+    get "legacy/people" => "people#index", :legacy => "true"
+
+    get "symbols", controller: :symbols, action: :show, name: :as_symbol
+    get "id_default(/:id)" => "foo#id_default", :id => 1
+    match "get_or_post" => "foo#get_or_post", :via => [:get, :post]
+    get "optional/:optional" => "posts#index"
+    get "projects/:project_id" => "project#index", :as => "project"
+    get "clients" => "projects#index"
+
+    get "ignorecase/geocode/:postalcode" => "geocode#show", :postalcode => /hx\d\d-\d[a-z]{2}/i
+    get "extended/geocode/:postalcode" => "geocode#show", :constraints => {
+                  postalcode: /# Postcode format
                                   \d{5} #Prefix
                                   (-\d{4})? #Suffix
                                   /x
                   }, :as => "geocode"
 
-    get 'news(.:format)' => "news#index"
+    get "news(.:format)" => "news#index"
 
     ActiveSupport::Deprecation.silence do
-      get 'comment/:id(/:action)' => "comments#show"
-      get 'ws/:controller(/:action(/:id))', :ws => true
-      get 'account(/:action)' => "account#subscription"
-      get 'pages/:page_id/:controller(/:action(/:id))'
-      get ':controller/ping', :action => 'ping'
+      get "comment/:id(/:action)" => "comments#show"
+      get "ws/:controller(/:action(/:id))", ws: true
+      get "account(/:action)" => "account#subscription"
+      get "pages/:page_id/:controller(/:action(/:id))"
+      get ":controller/ping", action: "ping"
     end
 
-    get 'こんにちは/世界', :controller => 'news', :action => 'index'
+    get "こんにちは/世界", controller: "news", action: "index"
 
     ActiveSupport::Deprecation.silence do
-      match ':controller(/:action(/:id))(.:format)', :via => :all
+      match ":controller(/:action(/:id))(.:format)", via: :all
     end
 
-    root :to => "news#index"
+    root to: "news#index"
   }
 
   attr_reader :routes
@@ -1969,118 +1984,118 @@ class RackMountIntegrationTests < ActiveSupport::TestCase
   end
 
   def test_recognize_path
-    assert_equal({:controller => 'admin/users', :action => 'index'}, @routes.recognize_path('/admin/users', :method => :get))
-    assert_equal({:controller => 'admin/users', :action => 'create'}, @routes.recognize_path('/admin/users', :method => :post))
-    assert_equal({:controller => 'admin/users', :action => 'new'}, @routes.recognize_path('/admin/users/new', :method => :get))
-    assert_equal({:controller => 'admin/users', :action => 'show', :id => '1'}, @routes.recognize_path('/admin/users/1', :method => :get))
-    assert_equal({:controller => 'admin/users', :action => 'update', :id => '1'}, @routes.recognize_path('/admin/users/1', :method => :put))
-    assert_equal({:controller => 'admin/users', :action => 'destroy', :id => '1'}, @routes.recognize_path('/admin/users/1', :method => :delete))
-    assert_equal({:controller => 'admin/users', :action => 'edit', :id => '1'}, @routes.recognize_path('/admin/users/1/edit', :method => :get))
-
-    assert_equal({:controller => 'admin/posts', :action => 'index'}, @routes.recognize_path('/admin/posts', :method => :get))
-    assert_equal({:controller => 'admin/posts', :action => 'new'}, @routes.recognize_path('/admin/posts/new', :method => :get))
-
-    assert_equal({:controller => 'api/users', :action => 'index'}, @routes.recognize_path('/api', :method => :get))
-    assert_equal({:controller => 'api/users', :action => 'index'}, @routes.recognize_path('/api/', :method => :get))
-
-    assert_equal({:controller => 'posts', :action => 'show_date', :year => '2009', :month => nil, :day => nil }, @routes.recognize_path('/blog/2009', :method => :get))
-    assert_equal({:controller => 'posts', :action => 'show_date', :year => '2009', :month => '01', :day => nil }, @routes.recognize_path('/blog/2009/01', :method => :get))
-    assert_equal({:controller => 'posts', :action => 'show_date', :year => '2009', :month => '01', :day => '01'}, @routes.recognize_path('/blog/2009/01/01', :method => :get))
-
-    assert_equal({:controller => 'archive', :action => 'index', :year => '2010'}, @routes.recognize_path('/archive/2010'))
-    assert_equal({:controller => 'archive', :action => 'index'}, @routes.recognize_path('/archive'))
-
-    assert_equal({:controller => 'people', :action => 'index'}, @routes.recognize_path('/people', :method => :get))
-    assert_equal({:controller => 'people', :action => 'index', :format => 'xml'}, @routes.recognize_path('/people.xml', :method => :get))
-    assert_equal({:controller => 'people', :action => 'create'}, @routes.recognize_path('/people', :method => :post))
-    assert_equal({:controller => 'people', :action => 'new'}, @routes.recognize_path('/people/new', :method => :get))
-    assert_equal({:controller => 'people', :action => 'show', :id => '1'}, @routes.recognize_path('/people/1', :method => :get))
-    assert_equal({:controller => 'people', :action => 'show', :id => '1', :format => 'xml'}, @routes.recognize_path('/people/1.xml', :method => :get))
-    assert_equal({:controller => 'people', :action => 'update', :id => '1'}, @routes.recognize_path('/people/1', :method => :put))
-    assert_equal({:controller => 'people', :action => 'destroy', :id => '1'}, @routes.recognize_path('/people/1', :method => :delete))
-    assert_equal({:controller => 'people', :action => 'edit', :id => '1'}, @routes.recognize_path('/people/1/edit', :method => :get))
-    assert_equal({:controller => 'people', :action => 'edit', :id => '1', :format => 'xml'}, @routes.recognize_path('/people/1/edit.xml', :method => :get))
-
-    assert_equal({:controller => 'symbols', :action => 'show', :name => :as_symbol}, @routes.recognize_path('/symbols'))
-    assert_equal({:controller => 'foo', :action => 'id_default', :id => '1'}, @routes.recognize_path('/id_default/1'))
-    assert_equal({:controller => 'foo', :action => 'id_default', :id => '2'}, @routes.recognize_path('/id_default/2'))
-    assert_equal({:controller => 'foo', :action => 'id_default', :id => 1 }, @routes.recognize_path('/id_default'))
-    assert_equal({:controller => 'foo', :action => 'get_or_post'}, @routes.recognize_path('/get_or_post', :method => :get))
-    assert_equal({:controller => 'foo', :action => 'get_or_post'}, @routes.recognize_path('/get_or_post', :method => :post))
-    assert_raise(ActionController::RoutingError) { @routes.recognize_path('/get_or_post', :method => :put) }
-    assert_raise(ActionController::RoutingError) { @routes.recognize_path('/get_or_post', :method => :delete) }
-
-    assert_equal({:controller => 'posts', :action => 'index', :optional => 'bar'}, @routes.recognize_path('/optional/bar'))
-    assert_raise(ActionController::RoutingError) { @routes.recognize_path('/optional') }
-
-    assert_equal({:controller => 'posts', :action => 'show', :id => '1', :ws => true}, @routes.recognize_path('/ws/posts/show/1', :method => :get))
-    assert_equal({:controller => 'posts', :action => 'list', :ws => true}, @routes.recognize_path('/ws/posts/list', :method => :get))
-    assert_equal({:controller => 'posts', :action => 'index', :ws => true}, @routes.recognize_path('/ws/posts', :method => :get))
-
-    assert_equal({:controller => 'account', :action => 'subscription'}, @routes.recognize_path('/account', :method => :get))
-    assert_equal({:controller => 'account', :action => 'subscription'}, @routes.recognize_path('/account/subscription', :method => :get))
-    assert_equal({:controller => 'account', :action => 'billing'}, @routes.recognize_path('/account/billing', :method => :get))
-
-    assert_equal({:page_id => '1', :controller => 'notes', :action => 'index'}, @routes.recognize_path('/pages/1/notes', :method => :get))
-    assert_equal({:page_id => '1', :controller => 'notes', :action => 'list'}, @routes.recognize_path('/pages/1/notes/list', :method => :get))
-    assert_equal({:page_id => '1', :controller => 'notes', :action => 'show', :id => '2'}, @routes.recognize_path('/pages/1/notes/show/2', :method => :get))
-
-    assert_equal({:controller => 'posts', :action => 'ping'}, @routes.recognize_path('/posts/ping', :method => :get))
-    assert_equal({:controller => 'posts', :action => 'index'}, @routes.recognize_path('/posts', :method => :get))
-    assert_equal({:controller => 'posts', :action => 'index'}, @routes.recognize_path('/posts/index', :method => :get))
-    assert_equal({:controller => 'posts', :action => 'show'}, @routes.recognize_path('/posts/show', :method => :get))
-    assert_equal({:controller => 'posts', :action => 'show', :id => '1'}, @routes.recognize_path('/posts/show/1', :method => :get))
-    assert_equal({:controller => 'posts', :action => 'create'}, @routes.recognize_path('/posts/create', :method => :post))
-
-    assert_equal({:controller => 'geocode', :action => 'show', :postalcode => 'hx12-1az'}, @routes.recognize_path('/ignorecase/geocode/hx12-1az'))
-    assert_equal({:controller => 'geocode', :action => 'show', :postalcode => 'hx12-1AZ'}, @routes.recognize_path('/ignorecase/geocode/hx12-1AZ'))
-    assert_equal({:controller => 'geocode', :action => 'show', :postalcode => '12345-1234'}, @routes.recognize_path('/extended/geocode/12345-1234'))
-    assert_equal({:controller => 'geocode', :action => 'show', :postalcode => '12345'}, @routes.recognize_path('/extended/geocode/12345'))
-
-    assert_equal({:controller => 'news', :action => 'index' }, @routes.recognize_path('/', :method => :get))
-    assert_equal({:controller => 'news', :action => 'index', :format => 'rss'}, @routes.recognize_path('/news.rss', :method => :get))
-
-    assert_raise(ActionController::RoutingError) { @routes.recognize_path('/none', :method => :get) }
+    assert_equal({ controller: "admin/users", action: "index" }, @routes.recognize_path("/admin/users", method: :get))
+    assert_equal({ controller: "admin/users", action: "create" }, @routes.recognize_path("/admin/users", method: :post))
+    assert_equal({ controller: "admin/users", action: "new" }, @routes.recognize_path("/admin/users/new", method: :get))
+    assert_equal({ controller: "admin/users", action: "show", id: "1" }, @routes.recognize_path("/admin/users/1", method: :get))
+    assert_equal({ controller: "admin/users", action: "update", id: "1" }, @routes.recognize_path("/admin/users/1", method: :put))
+    assert_equal({ controller: "admin/users", action: "destroy", id: "1" }, @routes.recognize_path("/admin/users/1", method: :delete))
+    assert_equal({ controller: "admin/users", action: "edit", id: "1" }, @routes.recognize_path("/admin/users/1/edit", method: :get))
+
+    assert_equal({ controller: "admin/posts", action: "index" }, @routes.recognize_path("/admin/posts", method: :get))
+    assert_equal({ controller: "admin/posts", action: "new" }, @routes.recognize_path("/admin/posts/new", method: :get))
+
+    assert_equal({ controller: "api/users", action: "index" }, @routes.recognize_path("/api", method: :get))
+    assert_equal({ controller: "api/users", action: "index" }, @routes.recognize_path("/api/", method: :get))
+
+    assert_equal({ controller: "posts", action: "show_date", year: "2009", month: nil, day: nil }, @routes.recognize_path("/blog/2009", method: :get))
+    assert_equal({ controller: "posts", action: "show_date", year: "2009", month: "01", day: nil }, @routes.recognize_path("/blog/2009/01", method: :get))
+    assert_equal({ controller: "posts", action: "show_date", year: "2009", month: "01", day: "01" }, @routes.recognize_path("/blog/2009/01/01", method: :get))
+
+    assert_equal({ controller: "archive", action: "index", year: "2010" }, @routes.recognize_path("/archive/2010"))
+    assert_equal({ controller: "archive", action: "index" }, @routes.recognize_path("/archive"))
+
+    assert_equal({ controller: "people", action: "index" }, @routes.recognize_path("/people", method: :get))
+    assert_equal({ controller: "people", action: "index", format: "xml" }, @routes.recognize_path("/people.xml", method: :get))
+    assert_equal({ controller: "people", action: "create" }, @routes.recognize_path("/people", method: :post))
+    assert_equal({ controller: "people", action: "new" }, @routes.recognize_path("/people/new", method: :get))
+    assert_equal({ controller: "people", action: "show", id: "1" }, @routes.recognize_path("/people/1", method: :get))
+    assert_equal({ controller: "people", action: "show", id: "1", format: "xml" }, @routes.recognize_path("/people/1.xml", method: :get))
+    assert_equal({ controller: "people", action: "update", id: "1" }, @routes.recognize_path("/people/1", method: :put))
+    assert_equal({ controller: "people", action: "destroy", id: "1" }, @routes.recognize_path("/people/1", method: :delete))
+    assert_equal({ controller: "people", action: "edit", id: "1" }, @routes.recognize_path("/people/1/edit", method: :get))
+    assert_equal({ controller: "people", action: "edit", id: "1", format: "xml" }, @routes.recognize_path("/people/1/edit.xml", method: :get))
+
+    assert_equal({ controller: "symbols", action: "show", name: :as_symbol }, @routes.recognize_path("/symbols"))
+    assert_equal({ controller: "foo", action: "id_default", id: "1" }, @routes.recognize_path("/id_default/1"))
+    assert_equal({ controller: "foo", action: "id_default", id: "2" }, @routes.recognize_path("/id_default/2"))
+    assert_equal({ controller: "foo", action: "id_default", id: 1 }, @routes.recognize_path("/id_default"))
+    assert_equal({ controller: "foo", action: "get_or_post" }, @routes.recognize_path("/get_or_post", method: :get))
+    assert_equal({ controller: "foo", action: "get_or_post" }, @routes.recognize_path("/get_or_post", method: :post))
+    assert_raise(ActionController::RoutingError) { @routes.recognize_path("/get_or_post", method: :put) }
+    assert_raise(ActionController::RoutingError) { @routes.recognize_path("/get_or_post", method: :delete) }
+
+    assert_equal({ controller: "posts", action: "index", optional: "bar" }, @routes.recognize_path("/optional/bar"))
+    assert_raise(ActionController::RoutingError) { @routes.recognize_path("/optional") }
+
+    assert_equal({ controller: "posts", action: "show", id: "1", ws: true }, @routes.recognize_path("/ws/posts/show/1", method: :get))
+    assert_equal({ controller: "posts", action: "list", ws: true }, @routes.recognize_path("/ws/posts/list", method: :get))
+    assert_equal({ controller: "posts", action: "index", ws: true }, @routes.recognize_path("/ws/posts", method: :get))
+
+    assert_equal({ controller: "account", action: "subscription" }, @routes.recognize_path("/account", method: :get))
+    assert_equal({ controller: "account", action: "subscription" }, @routes.recognize_path("/account/subscription", method: :get))
+    assert_equal({ controller: "account", action: "billing" }, @routes.recognize_path("/account/billing", method: :get))
+
+    assert_equal({ page_id: "1", controller: "notes", action: "index" }, @routes.recognize_path("/pages/1/notes", method: :get))
+    assert_equal({ page_id: "1", controller: "notes", action: "list" }, @routes.recognize_path("/pages/1/notes/list", method: :get))
+    assert_equal({ page_id: "1", controller: "notes", action: "show", id: "2" }, @routes.recognize_path("/pages/1/notes/show/2", method: :get))
+
+    assert_equal({ controller: "posts", action: "ping" }, @routes.recognize_path("/posts/ping", method: :get))
+    assert_equal({ controller: "posts", action: "index" }, @routes.recognize_path("/posts", method: :get))
+    assert_equal({ controller: "posts", action: "index" }, @routes.recognize_path("/posts/index", method: :get))
+    assert_equal({ controller: "posts", action: "show" }, @routes.recognize_path("/posts/show", method: :get))
+    assert_equal({ controller: "posts", action: "show", id: "1" }, @routes.recognize_path("/posts/show/1", method: :get))
+    assert_equal({ controller: "posts", action: "create" }, @routes.recognize_path("/posts/create", method: :post))
+
+    assert_equal({ controller: "geocode", action: "show", postalcode: "hx12-1az" }, @routes.recognize_path("/ignorecase/geocode/hx12-1az"))
+    assert_equal({ controller: "geocode", action: "show", postalcode: "hx12-1AZ" }, @routes.recognize_path("/ignorecase/geocode/hx12-1AZ"))
+    assert_equal({ controller: "geocode", action: "show", postalcode: "12345-1234" }, @routes.recognize_path("/extended/geocode/12345-1234"))
+    assert_equal({ controller: "geocode", action: "show", postalcode: "12345" }, @routes.recognize_path("/extended/geocode/12345"))
+
+    assert_equal({ controller: "news", action: "index" }, @routes.recognize_path("/", method: :get))
+    assert_equal({ controller: "news", action: "index", format: "rss" }, @routes.recognize_path("/news.rss", method: :get))
+
+    assert_raise(ActionController::RoutingError) { @routes.recognize_path("/none", method: :get) }
   end
 
   def test_generate_extras
-    assert_equal ['/people', []], @routes.generate_extras(:controller => 'people')
-    assert_equal ['/people', [:foo]], @routes.generate_extras(:controller => 'people', :foo => 'bar')
-    assert_equal ['/people', []], @routes.generate_extras(:controller => 'people', :action => 'index')
-    assert_equal ['/people', [:foo]], @routes.generate_extras(:controller => 'people', :action => 'index', :foo => 'bar')
-    assert_equal ['/people/new', []], @routes.generate_extras(:controller => 'people', :action => 'new')
-    assert_equal ['/people/new', [:foo]], @routes.generate_extras(:controller => 'people', :action => 'new', :foo => 'bar')
-    assert_equal ['/people/1', []], @routes.generate_extras(:controller => 'people', :action => 'show', :id => '1')
-    assert_equal ['/people/1', [:bar, :foo]], sort_extras!(@routes.generate_extras(:controller => 'people', :action => 'show', :id => '1', :foo => '2', :bar => '3'))
-    assert_equal ['/people', [:person]], @routes.generate_extras(:controller => 'people', :action => 'create', :person => { :first_name => 'Josh', :last_name => 'Peek' })
-    assert_equal ['/people', [:people]], @routes.generate_extras(:controller => 'people', :action => 'create', :people => ['Josh', 'Dave'])
-
-    assert_equal ['/posts/show/1', []], @routes.generate_extras(:controller => 'posts', :action => 'show', :id => '1')
-    assert_equal ['/posts/show/1', [:bar, :foo]], sort_extras!(@routes.generate_extras(:controller => 'posts', :action => 'show', :id => '1', :foo => '2', :bar => '3'))
-    assert_equal ['/posts', []], @routes.generate_extras(:controller => 'posts', :action => 'index')
-    assert_equal ['/posts', [:foo]], @routes.generate_extras(:controller => 'posts', :action => 'index', :foo => 'bar')
+    assert_equal ["/people", []], @routes.generate_extras(controller: "people")
+    assert_equal ["/people", [:foo]], @routes.generate_extras(controller: "people", foo: "bar")
+    assert_equal ["/people", []], @routes.generate_extras(controller: "people", action: "index")
+    assert_equal ["/people", [:foo]], @routes.generate_extras(controller: "people", action: "index", foo: "bar")
+    assert_equal ["/people/new", []], @routes.generate_extras(controller: "people", action: "new")
+    assert_equal ["/people/new", [:foo]], @routes.generate_extras(controller: "people", action: "new", foo: "bar")
+    assert_equal ["/people/1", []], @routes.generate_extras(controller: "people", action: "show", id: "1")
+    assert_equal ["/people/1", [:bar, :foo]], sort_extras!(@routes.generate_extras(controller: "people", action: "show", id: "1", foo: "2", bar: "3"))
+    assert_equal ["/people", [:person]], @routes.generate_extras(controller: "people", action: "create", person: { first_name: "Josh", last_name: "Peek" })
+    assert_equal ["/people", [:people]], @routes.generate_extras(controller: "people", action: "create", people: ["Josh", "Dave"])
+
+    assert_equal ["/posts/show/1", []], @routes.generate_extras(controller: "posts", action: "show", id: "1")
+    assert_equal ["/posts/show/1", [:bar, :foo]], sort_extras!(@routes.generate_extras(controller: "posts", action: "show", id: "1", foo: "2", bar: "3"))
+    assert_equal ["/posts", []], @routes.generate_extras(controller: "posts", action: "index")
+    assert_equal ["/posts", [:foo]], @routes.generate_extras(controller: "posts", action: "index", foo: "bar")
   end
 
   def test_extras
-    params = {:controller => 'people'}
+    params = { controller: "people" }
     assert_equal [], @routes.extra_keys(params)
-    assert_equal({:controller => 'people', :action => 'index'}, params)
+    assert_equal({ controller: "people", action: "index" }, params)
 
-    params = {:controller => 'people', :foo => 'bar'}
+    params = { controller: "people", foo: "bar" }
     assert_equal [:foo], @routes.extra_keys(params)
-    assert_equal({:controller => 'people', :action => 'index', :foo => 'bar'}, params)
+    assert_equal({ controller: "people", action: "index", foo: "bar" }, params)
 
-    params = {:controller => 'people', :action => 'create', :person => { :name => 'Josh'}}
+    params = { controller: "people", action: "create", person: { name: "Josh" } }
     assert_equal [:person], @routes.extra_keys(params)
-    assert_equal({:controller => 'people', :action => 'create', :person => { :name => 'Josh'}}, params)
+    assert_equal({ controller: "people", action: "create", person: { name: "Josh" } }, params)
   end
 
   def test_unicode_path
-    assert_equal({:controller => 'news', :action => 'index'}, @routes.recognize_path(URI.parser.escape('こんにちは/世界'), :method => :get))
+    assert_equal({ controller: "news", action: "index" }, @routes.recognize_path(URI.parser.escape("こんにちは/世界"), method: :get))
   end
 
   def test_downcased_unicode_path
-    assert_equal({:controller => 'news', :action => 'index'}, @routes.recognize_path(URI.parser.escape('こんにちは/世界').downcase, :method => :get))
+    assert_equal({ controller: "news", action: "index" }, @routes.recognize_path(URI.parser.escape("こんにちは/世界").downcase, method: :get))
   end
 
   private
diff --git a/actionpack/test/controller/runner_test.rb b/actionpack/test/controller/runner_test.rb
index 3e9383abb2..a96c9c519b 100644
--- a/actionpack/test/controller/runner_test.rb
+++ b/actionpack/test/controller/runner_test.rb
@@ -1,5 +1,7 @@
-require 'abstract_unit'
-require 'action_dispatch/testing/integration'
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "action_dispatch/testing/integration"
 
 module ActionDispatch
   class RunnerTest < ActiveSupport::TestCase
diff --git a/actionpack/test/controller/send_file_test.rb b/actionpack/test/controller/send_file_test.rb
index 9df70dacbf..7b1a52b277 100644
--- a/actionpack/test/controller/send_file_test.rb
+++ b/actionpack/test/controller/send_file_test.rb
@@ -1,9 +1,11 @@
-require 'abstract_unit'
+# frozen_string_literal: true
+
+require "abstract_unit"
 
 module TestFileUtils
   def file_name() File.basename(__FILE__) end
-  def file_path() File.expand_path(__FILE__) end
-  def file_data() @data ||= File.open(file_path, 'rb') { |f| f.read } end
+  def file_path() __FILE__ end
+  def file_data() @data ||= File.open(file_path, "rb") { |f| f.read } end
 end
 
 class SendFileController < ActionController::Base
@@ -23,14 +25,14 @@ class SendFileController < ActionController::Base
   end
 
   def file_from_before_action
-    raise 'No file sent from before action.'
+    raise "No file sent from before action."
   end
 
   def test_send_file_headers_bang
     options = {
-      :type => Mime[:png],
-      :disposition => 'disposition',
-      :filename => 'filename'
+      type: Mime[:png],
+      disposition: "disposition",
+      filename: "filename"
     }
 
     send_data "foo", options
@@ -38,32 +40,32 @@ class SendFileController < ActionController::Base
 
   def test_send_file_headers_with_disposition_as_a_symbol
     options = {
-      :type => Mime[:png],
-      :disposition => :disposition,
-      :filename => 'filename'
+      type: Mime[:png],
+      disposition: :disposition,
+      filename: "filename"
     }
 
     send_data "foo", options
   end
 
   def test_send_file_headers_with_mime_lookup_with_symbol
-    options = { :type => :png }
+    options = { type: :png }
 
     send_data "foo", options
   end
 
   def test_send_file_headers_with_bad_symbol
-    options = { :type => :this_type_is_not_registered }
+    options = { type: :this_type_is_not_registered }
     send_data "foo", options
   end
 
   def test_send_file_headers_with_nil_content_type
-    options = { :type => nil }
+    options = { type: nil }
     send_data "foo", options
   end
 
   def test_send_file_headers_guess_type_from_extension
-    options = { :filename => params[:filename] }
+    options = { filename: params[:filename] }
     send_data "foo", options
   end
 
@@ -84,9 +86,9 @@ class SendFileTest < ActionController::TestCase
   end
 
   def test_file_nostream
-    @controller.options = { :stream => false }
+    @controller.options = { stream: false }
     response = nil
-    assert_nothing_raised { response = process('file') }
+    assert_nothing_raised { response = process("file") }
     assert_not_nil response
     body = response.body
     assert_kind_of String, body
@@ -95,12 +97,12 @@ class SendFileTest < ActionController::TestCase
 
   def test_file_stream
     response = nil
-    assert_nothing_raised { response = process('file') }
+    assert_nothing_raised { response = process("file") }
     assert_not_nil response
     assert_respond_to response.stream, :each
     assert_respond_to response.stream, :to_path
 
-    require 'stringio'
+    require "stringio"
     output = StringIO.new
     output.binmode
     output.string.force_encoding(file_data.encoding)
@@ -109,16 +111,16 @@ class SendFileTest < ActionController::TestCase
   end
 
   def test_file_url_based_filename
-    @controller.options = { :url_based_filename => true }
+    @controller.options = { url_based_filename: true }
     response = nil
-    assert_nothing_raised { response = process('file') }
+    assert_nothing_raised { response = process("file") }
     assert_not_nil response
     assert_equal "attachment", response.headers["Content-Disposition"]
   end
 
   def test_data
     response = nil
-    assert_nothing_raised { response = process('data') }
+    assert_nothing_raised { response = process("data") }
     assert_not_nil response
 
     assert_kind_of String, response.body
@@ -126,10 +128,10 @@ class SendFileTest < ActionController::TestCase
   end
 
   def test_headers_after_send_shouldnt_include_charset
-    response = process('data')
+    response = process("data")
     assert_equal "application/octet-stream", response.headers["Content-Type"]
 
-    response = process('file')
+    response = process("file")
     assert_equal "application/octet-stream", response.headers["Content-Type"]
   end
 
@@ -141,25 +143,24 @@ class SendFileTest < ActionController::TestCase
     5.times do
       get :test_send_file_headers_bang
 
-      assert_equal 'image/png', response.content_type
-      assert_equal 'disposition; filename="filename"', response.get_header('Content-Disposition')
-      assert_equal 'binary', response.get_header('Content-Transfer-Encoding')
-      assert_equal 'private', response.get_header('Cache-Control')
+      assert_equal "image/png", response.content_type
+      assert_equal 'disposition; filename="filename"', response.get_header("Content-Disposition")
+      assert_equal "binary", response.get_header("Content-Transfer-Encoding")
+      assert_equal "private", response.get_header("Cache-Control")
     end
   end
 
   def test_send_file_headers_with_disposition_as_a_symbol
     get :test_send_file_headers_with_disposition_as_a_symbol
 
-    assert_equal 'disposition; filename="filename"', response.get_header('Content-Disposition')
+    assert_equal 'disposition; filename="filename"', response.get_header("Content-Disposition")
   end
 
   def test_send_file_headers_with_mime_lookup_with_symbol
     get __method__
-    assert_equal 'image/png', response.content_type
+    assert_equal "image/png", response.content_type
   end
 
-
   def test_send_file_headers_with_bad_symbol
     error = assert_raise(ArgumentError) { get __method__ }
     assert_equal "Unknown MIME type this_type_is_not_registered", error.message
@@ -172,35 +173,35 @@ class SendFileTest < ActionController::TestCase
 
   def test_send_file_headers_guess_type_from_extension
     {
-      'image.png' => 'image/png',
-      'image.jpeg' => 'image/jpeg',
-      'image.jpg' => 'image/jpeg',
-      'image.tif' => 'image/tiff',
-      'image.gif' => 'image/gif',
-      'movie.mpg' => 'video/mpeg',
-      'file.zip' => 'application/zip',
-      'file.unk' => 'application/octet-stream',
-      'zip' => 'application/octet-stream'
-    }.each do |filename,expected_type|
+      "image.png" => "image/png",
+      "image.jpeg" => "image/jpeg",
+      "image.jpg" => "image/jpeg",
+      "image.tif" => "image/tiff",
+      "image.gif" => "image/gif",
+      "movie.mp4" => "video/mp4",
+      "file.zip" => "application/zip",
+      "file.unk" => "application/octet-stream",
+      "zip" => "application/octet-stream"
+    }.each do |filename, expected_type|
       get __method__, params: { filename: filename }
       assert_equal expected_type, response.content_type
     end
   end
 
   def test_send_file_with_default_content_disposition_header
-    process('data')
-    assert_equal 'attachment', @controller.headers['Content-Disposition']
+    process("data")
+    assert_equal "attachment", @controller.headers["Content-Disposition"]
   end
 
   def test_send_file_without_content_disposition_header
-    @controller.options = {:disposition => nil}
-    process('data')
-    assert_nil @controller.headers['Content-Disposition']
+    @controller.options = { disposition: nil }
+    process("data")
+    assert_nil @controller.headers["Content-Disposition"]
   end
 
   def test_send_file_from_before_action
     response = nil
-    assert_nothing_raised { response = process('file_from_before_action') }
+    assert_nothing_raised { response = process("file_from_before_action") }
     assert_not_nil response
 
     assert_kind_of String, response.body
@@ -209,19 +210,19 @@ class SendFileTest < ActionController::TestCase
 
   %w(file data).each do |method|
     define_method "test_send_#{method}_status" do
-      @controller.options = { :stream => false, :status => 500 }
+      @controller.options = { stream: false, status: 500 }
       assert_not_nil process(method)
       assert_equal 500, @response.status
     end
 
     define_method "test_send_#{method}_content_type" do
-      @controller.options = { :stream => false, :content_type => "application/x-ruby" }
+      @controller.options = { stream: false, content_type: "application/x-ruby" }
       assert_nothing_raised { assert_not_nil process(method) }
       assert_equal "application/x-ruby", @response.content_type
     end
 
     define_method "test_default_send_#{method}_status" do
-      @controller.options = { :stream => false }
+      @controller.options = { stream: false }
       assert_nothing_raised { assert_not_nil process(method) }
       assert_equal 200, @response.status
     end
@@ -229,9 +230,30 @@ class SendFileTest < ActionController::TestCase
 
   def test_send_file_with_action_controller_live
     @controller = SendFileWithActionControllerLive.new
-    @controller.options = { :content_type => "application/x-ruby" }
+    @controller.options = { content_type: "application/x-ruby" }
 
-    response = process('file')
+    response = process("file")
     assert_equal 200, response.status
   end
+
+  def test_send_file_charset_with_type_options_key
+    @controller = SendFileWithActionControllerLive.new
+    @controller.options = { type: "text/calendar; charset=utf-8" }
+    response = process("file")
+    assert_equal "text/calendar; charset=utf-8", response.headers["Content-Type"]
+  end
+
+  def test_send_file_charset_with_type_options_key_without_charset
+    @controller = SendFileWithActionControllerLive.new
+    @controller.options = { type: "image/png" }
+    response = process("file")
+    assert_equal "image/png", response.headers["Content-Type"]
+  end
+
+  def test_send_file_charset_with_content_type_options_key
+    @controller = SendFileWithActionControllerLive.new
+    @controller.options = { content_type: "text/calendar" }
+    response = process("file")
+    assert_equal "text/calendar", response.headers["Content-Type"]
+  end
 end
diff --git a/actionpack/test/controller/show_exceptions_test.rb b/actionpack/test/controller/show_exceptions_test.rb
index 786dc15444..2094aa1aed 100644
--- a/actionpack/test/controller/show_exceptions_test.rb
+++ b/actionpack/test/controller/show_exceptions_test.rb
@@ -1,4 +1,6 @@
-require 'abstract_unit'
+# frozen_string_literal: true
+
+require "abstract_unit"
 
 module ShowExceptions
   class ShowExceptionsController < ActionController::Base
@@ -10,11 +12,11 @@ module ShowExceptions
     end
 
     def boom
-      raise 'boom!'
+      raise "boom!"
     end
 
     def another_boom
-      raise 'boom!'
+      raise "boom!"
     end
 
     def show_detailed_exceptions?
@@ -23,26 +25,26 @@ module ShowExceptions
   end
 
   class ShowExceptionsTest < ActionDispatch::IntegrationTest
-    test 'show error page from a remote ip' do
+    test "show error page from a remote ip" do
       @app = ShowExceptionsController.action(:boom)
-      self.remote_addr = '208.77.188.166'
-      get '/'
+      self.remote_addr = "208.77.188.166"
+      get "/"
       assert_equal "500 error fixture\n", body
     end
 
-    test 'show diagnostics from a local ip if show_detailed_exceptions? is set to request.local?' do
+    test "show diagnostics from a local ip if show_detailed_exceptions? is set to request.local?" do
       @app = ShowExceptionsController.action(:boom)
-      ['127.0.0.1', '127.0.0.127', '127.12.1.1', '::1', '0:0:0:0:0:0:0:1', '0:0:0:0:0:0:0:1%0'].each do |ip_address|
+      ["127.0.0.1", "127.0.0.127", "127.12.1.1", "::1", "0:0:0:0:0:0:0:1", "0:0:0:0:0:0:0:1%0"].each do |ip_address|
         self.remote_addr = ip_address
-        get '/'
+        get "/"
         assert_match(/boom/, body)
       end
     end
 
-    test 'show diagnostics from a remote ip when env is already set' do
+    test "show diagnostics from a remote ip when env is already set" do
       @app = ShowExceptionsController.action(:another_boom)
-      self.remote_addr = '208.77.188.166'
-      get '/'
+      self.remote_addr = "208.77.188.166"
+      get "/"
       assert_match(/boom/, body)
     end
   end
@@ -50,21 +52,21 @@ module ShowExceptions
   class ShowExceptionsOverriddenController < ShowExceptionsController
     private
 
-    def show_detailed_exceptions?
-      params['detailed'] == '1'
-    end
+      def show_detailed_exceptions?
+        params["detailed"] == "1"
+      end
   end
 
   class ShowExceptionsOverriddenTest < ActionDispatch::IntegrationTest
-    test 'show error page' do
+    test "show error page" do
       @app = ShowExceptionsOverriddenController.action(:boom)
-      get '/', params: { 'detailed' => '0' }
+      get "/", params: { "detailed" => "0" }
       assert_equal "500 error fixture\n", body
     end
 
-    test 'show diagnostics message' do
+    test "show diagnostics message" do
       @app = ShowExceptionsOverriddenController.action(:boom)
-      get '/', params: { 'detailed' => '1' }
+      get "/", params: { "detailed" => "1" }
       assert_match(/boom/, body)
     end
   end
@@ -72,25 +74,25 @@ module ShowExceptions
   class ShowExceptionsFormatsTest < ActionDispatch::IntegrationTest
     def test_render_json_exception
       @app = ShowExceptionsOverriddenController.action(:boom)
-      get "/", headers: { 'HTTP_ACCEPT' => 'application/json' }
+      get "/", headers: { "HTTP_ACCEPT" => "application/json" }
       assert_response :internal_server_error
-      assert_equal 'application/json', response.content_type.to_s
-      assert_equal({ :status => 500, :error => 'Internal Server Error' }.to_json, response.body)
+      assert_equal "application/json", response.content_type.to_s
+      assert_equal({ status: 500, error: "Internal Server Error" }.to_json, response.body)
     end
 
     def test_render_xml_exception
       @app = ShowExceptionsOverriddenController.action(:boom)
-      get "/", headers: { 'HTTP_ACCEPT' => 'application/xml' }
+      get "/", headers: { "HTTP_ACCEPT" => "application/xml" }
       assert_response :internal_server_error
-      assert_equal 'application/xml', response.content_type.to_s
-      assert_equal({ :status => 500, :error => 'Internal Server Error' }.to_xml, response.body)
+      assert_equal "application/xml", response.content_type.to_s
+      assert_equal({ status: 500, error: "Internal Server Error" }.to_xml, response.body)
     end
 
     def test_render_fallback_exception
       @app = ShowExceptionsOverriddenController.action(:boom)
-      get "/", headers: { 'HTTP_ACCEPT' => 'text/csv' }
+      get "/", headers: { "HTTP_ACCEPT" => "text/csv" }
       assert_response :internal_server_error
-      assert_equal 'text/html', response.content_type.to_s
+      assert_equal "text/html", response.content_type.to_s
     end
   end
 
@@ -101,9 +103,9 @@ module ShowExceptions
       @app.instance_variable_set(:@exceptions_app, nil)
       $stderr = StringIO.new
 
-      get '/', headers: { 'HTTP_ACCEPT' => 'text/json' }
+      get "/", headers: { "HTTP_ACCEPT" => "text/json" }
       assert_response :internal_server_error
-      assert_equal 'text/plain', response.content_type.to_s
+      assert_equal "text/plain", response.content_type.to_s
     ensure
       @app.instance_variable_set(:@exceptions_app, @exceptions_app)
       $stderr = STDERR
diff --git a/actionpack/test/controller/streaming_test.rb b/actionpack/test/controller/streaming_test.rb
index 6ee6444065..5a42e2ae6d 100644
--- a/actionpack/test/controller/streaming_test.rb
+++ b/actionpack/test/controller/streaming_test.rb
@@ -1,10 +1,12 @@
-require 'abstract_unit'
+# frozen_string_literal: true
+
+require "abstract_unit"
 
 module ActionController
   class StreamingResponseTest < ActionController::TestCase
     class TestController < ActionController::Base
       def self.controller_path
-        'test'
+        "test"
       end
 
       def basic_stream
diff --git a/actionpack/test/controller/test_case_test.rb b/actionpack/test/controller/test_case_test.rb
index ea59156f65..536c5ed97a 100644
--- a/actionpack/test/controller/test_case_test.rb
+++ b/actionpack/test/controller/test_case_test.rb
@@ -1,40 +1,42 @@
-require 'abstract_unit'
-require 'controller/fake_controllers'
-require 'active_support/json/decoding'
-require 'rails/engine'
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "controller/fake_controllers"
+require "active_support/json/decoding"
+require "rails/engine"
 
 class TestCaseTest < ActionController::TestCase
-  def self.fixture_path; end;
+  def self.fixture_path; end
 
   class TestController < ActionController::Base
     def no_op
-      render plain: 'dummy'
+      render plain: "dummy"
     end
 
     def set_flash
       flash["test"] = ">#{flash["test"]}<"
-      render plain: 'ignore me'
+      render plain: "ignore me"
     end
 
     def delete_flash
       flash.delete("test")
-      render plain: 'ignore me'
+      render plain: "ignore me"
     end
 
     def set_flash_now
       flash.now["test_now"] = ">#{flash["test_now"]}<"
-      render plain: 'ignore me'
+      render plain: "ignore me"
     end
 
     def set_session
-      session['string'] = 'A wonder'
-      session[:symbol] = 'it works'
-      render plain: 'Success'
+      session["string"] = "A wonder"
+      session[:symbol] = "it works"
+      render plain: "Success"
     end
 
     def reset_the_session
       reset_session
-      render plain: 'ignore me'
+      render plain: "ignore me"
     end
 
     def render_raw_post
@@ -100,11 +102,11 @@ HTML
     end
 
     def test_xml_output
-      response.content_type = "application/xml"
+      response.content_type = params[:response_as]
       render plain: <<XML
 <?xml version="1.0" encoding="UTF-8"?>
 <root>
-  <area>area is an empty tag in HTML, raising an error if not in xml mode</area>
+  <area><p>area is an empty tag in HTML, so it won't contain this content</p></area>
 </root>
 XML
     end
@@ -122,19 +124,19 @@ XML
     end
 
     def test_send_file
-      send_file(File.expand_path(__FILE__))
+      send_file(__FILE__)
     end
 
     def redirect_to_same_controller
-      redirect_to controller: 'test', action: 'test_uri', id: 5
+      redirect_to controller: "test", action: "test_uri", id: 5
     end
 
     def redirect_to_different_controller
-      redirect_to controller: 'fail', id: 5
+      redirect_to controller: "fail", id: 5
     end
 
     def create
-      head :created, location: 'created resource'
+      head :created, location: "/resource"
     end
 
     def render_cookie
@@ -143,7 +145,7 @@ XML
 
     def delete_cookie
       cookies.delete("foo")
-      render plain: 'ok'
+      render plain: "ok"
     end
 
     def test_without_body
@@ -155,7 +157,7 @@ XML
     end
 
     def boom
-      raise 'boom!'
+      raise "boom!"
     end
 
     private
@@ -168,18 +170,18 @@ XML
   def setup
     super
     @controller = TestController.new
-    @request.delete_header 'PATH_INFO'
+    @request.delete_header "PATH_INFO"
     @routes = ActionDispatch::Routing::RouteSet.new.tap do |r|
       r.draw do
         ActiveSupport::Deprecation.silence do
-          get ':controller(/:action(/:id))'
+          get ":controller(/:action(/:id))"
         end
       end
     end
   end
 
   class DefaultUrlOptionsCachingController < ActionController::Base
-    before_action { @dynamic_opt = 'opt' }
+    before_action { @dynamic_opt = "opt" }
 
     def test_url_options_reset
       render plain: url_for
@@ -197,49 +199,41 @@ XML
   def test_assert_select_without_body
     get :test_without_body
 
-    assert_select 'body', 0
-    assert_select 'div.foo'
+    assert_select "body", 0
+    assert_select "div.foo"
   end
 
   def test_assert_select_with_body
     get :test_with_body
 
-    assert_select 'body.foo'
+    assert_select "body.foo"
   end
 
   def test_url_options_reset
     @controller = DefaultUrlOptionsCachingController.new
     get :test_url_options_reset
-    assert_nil @request.params['dynamic_opt']
+    assert_nil @request.params["dynamic_opt"]
     assert_match(/dynamic_opt=opt/, @response.body)
   end
 
   def test_raw_post_handling
-    params = Hash[:page, { name: 'page name' }, 'some key', 123]
+    params = Hash[:page, { name: "page name" }, "some key", 123]
     post :render_raw_post, params: params.dup
 
     assert_equal params.to_query, @response.body
   end
 
   def test_body_stream
-    params = Hash[:page, { name: 'page name' }, 'some key', 123]
+    params = Hash[:page, { name: "page name" }, "some key", 123]
 
     post :render_body, params: params.dup
 
     assert_equal params.to_query, @response.body
   end
 
-  def test_deprecated_body_stream
-    params = Hash[:page, { name: 'page name' }, 'some key', 123]
-
-    assert_deprecated { post :render_body, params.dup }
-
-    assert_equal params.to_query, @response.body
-  end
-
   def test_document_body_and_params_with_post
     post :test_params, params: { id: 1 }
-    assert_equal({"id"=>"1", "controller"=>"test_case_test/test", "action"=>"test_params"}, ::JSON.parse(@response.body))
+    assert_equal({ "id" => "1", "controller" => "test_case_test/test", "action" => "test_params" }, ::JSON.parse(@response.body))
   end
 
   def test_document_body_with_post
@@ -247,21 +241,11 @@ XML
     assert_equal "document body", @response.body
   end
 
-  def test_deprecated_document_body_with_post
-    assert_deprecated { post :render_body, "document body" }
-    assert_equal "document body", @response.body
-  end
-
   def test_document_body_with_put
     put :render_body, body: "document body"
     assert_equal "document body", @response.body
   end
 
-  def test_deprecated_document_body_with_put
-    assert_deprecated { put :render_body, "document body" }
-    assert_equal "document body", @response.body
-  end
-
   def test_head
     head :test_params
     assert_equal 200, @response.status
@@ -269,31 +253,21 @@ XML
 
   def test_process_without_flash
     process :set_flash
-    assert_equal '><', flash['test']
-  end
-
-  def test_deprecated_process_with_flash
-    assert_deprecated { process :set_flash, "GET", nil, nil, { "test" => "value" } }
-    assert_equal '>value<', flash['test']
+    assert_equal "><", flash["test"]
   end
 
   def test_process_with_flash
     process :set_flash,
       method: "GET",
       flash: { "test" => "value" }
-    assert_equal '>value<', flash['test']
-  end
-
-  def test_deprecated_process_with_flash_now
-    assert_deprecated { process :set_flash_now, "GET", nil, nil, { "test_now" => "value_now" } }
-    assert_equal '>value_now<', flash['test_now']
+    assert_equal ">value<", flash["test"]
   end
 
   def test_process_with_flash_now
     process :set_flash_now,
       method: "GET",
       flash: { "test_now" => "value_now" }
-    assert_equal '>value_now<', flash['test_now']
+    assert_equal ">value_now<", flash["test_now"]
   end
 
   def test_process_delete_flash
@@ -305,64 +279,38 @@ XML
 
   def test_process_with_session
     process :set_session
-    assert_equal 'A wonder', session['string'], "A value stored in the session should be available by string key"
-    assert_equal 'A wonder', session[:string], "Test session hash should allow indifferent access"
-    assert_equal 'it works', session['symbol'], "Test session hash should allow indifferent access"
-    assert_equal 'it works', session[:symbol], "Test session hash should allow indifferent access"
-  end
-
-  def test_process_with_session_arg
-    assert_deprecated { process :no_op, "GET", nil, { 'string' => 'value1', symbol: 'value2' } }
-    assert_equal 'value1', session['string']
-    assert_equal 'value1', session[:string]
-    assert_equal 'value2', session['symbol']
-    assert_equal 'value2', session[:symbol]
+    assert_equal "A wonder", session["string"], "A value stored in the session should be available by string key"
+    assert_equal "A wonder", session[:string], "Test session hash should allow indifferent access"
+    assert_equal "it works", session["symbol"], "Test session hash should allow indifferent access"
+    assert_equal "it works", session[:symbol], "Test session hash should allow indifferent access"
   end
 
   def test_process_with_session_kwarg
-    process :no_op, method: "GET", session: { 'string' => 'value1', symbol: 'value2' }
-    assert_equal 'value1', session['string']
-    assert_equal 'value1', session[:string]
-    assert_equal 'value2', session['symbol']
-    assert_equal 'value2', session[:symbol]
-  end
-
-  def test_deprecated_process_merges_session_arg
-    session[:foo] = 'bar'
-    assert_deprecated {
-      get :no_op, nil, { bar: 'baz' }
-    }
-    assert_equal 'bar', session[:foo]
-    assert_equal 'baz', session[:bar]
+    process :no_op, method: "GET", session: { "string" => "value1", symbol: "value2" }
+    assert_equal "value1", session["string"]
+    assert_equal "value1", session[:string]
+    assert_equal "value2", session["symbol"]
+    assert_equal "value2", session[:symbol]
   end
 
   def test_process_merges_session_arg
-    session[:foo] = 'bar'
-    get :no_op, session: { bar: 'baz' }
-    assert_equal 'bar', session[:foo]
-    assert_equal 'baz', session[:bar]
-  end
-
-  def test_deprecated_merged_session_arg_is_retained_across_requests
-    assert_deprecated {
-      get :no_op, nil, { foo: 'bar' }
-    }
-    assert_equal 'bar', session[:foo]
-    get :no_op
-    assert_equal 'bar', session[:foo]
+    session[:foo] = "bar"
+    get :no_op, session: { bar: "baz" }
+    assert_equal "bar", session[:foo]
+    assert_equal "baz", session[:bar]
   end
 
   def test_merged_session_arg_is_retained_across_requests
-    get :no_op, session: { foo: 'bar' }
-    assert_equal 'bar', session[:foo]
+    get :no_op, session: { foo: "bar" }
+    assert_equal "bar", session[:foo]
     get :no_op
-    assert_equal 'bar', session[:foo]
+    assert_equal "bar", session[:foo]
   end
 
   def test_process_overwrites_existing_session_arg
-    session[:foo] = 'bar'
-    get :no_op, session: { foo: 'baz' }
-    assert_equal 'baz', session[:foo]
+    session[:foo] = "bar"
+    get :no_op, session: { foo: "baz" }
+    assert_equal "baz", session[:foo]
   end
 
   def test_session_is_cleared_from_controller_after_reset_session
@@ -393,11 +341,6 @@ XML
     assert_equal "/test_case_test/test/test_uri", @response.body
   end
 
-  def test_deprecated_process_with_request_uri_with_params
-    assert_deprecated { process :test_uri, "GET", id: 7 }
-    assert_equal "/test_case_test/test/test_uri/7", @response.body
-  end
-
   def test_process_with_request_uri_with_params
     process :test_uri,
       method: "GET",
@@ -406,14 +349,8 @@ XML
     assert_equal "/test_case_test/test/test_uri/7", @response.body
   end
 
-  def test_deprecated_process_with_request_uri_with_params_with_explicit_uri
-    @request.env['PATH_INFO'] = "/explicit/uri"
-    assert_deprecated { process :test_uri, "GET", id: 7 }
-    assert_equal "/explicit/uri", @response.body
-  end
-
   def test_process_with_request_uri_with_params_with_explicit_uri
-    @request.env['PATH_INFO'] = "/explicit/uri"
+    @request.env["PATH_INFO"] = "/explicit/uri"
     process :test_uri, method: "GET", params: { id: 7 }
     assert_equal "/explicit/uri", @response.body
   end
@@ -421,13 +358,13 @@ XML
   def test_process_with_query_string
     process :test_query_string,
       method: "GET",
-      params: { q: 'test' }
+      params: { q: "test" }
     assert_equal "q=test", @response.body
   end
 
   def test_process_with_query_string_with_explicit_uri
-    @request.env['PATH_INFO'] = '/explicit/uri'
-    @request.env['QUERY_STRING'] = 'q=test?extra=question'
+    @request.env["PATH_INFO"] = "/explicit/uri"
+    @request.env["QUERY_STRING"] = "q=test?extra=question"
     process :test_query_string
     assert_equal "q=test?extra=question", @response.body
   end
@@ -439,36 +376,36 @@ XML
     assert_equal "OK", @response.body
   end
 
-  def test_should_not_impose_childless_html_tags_in_xml
-    process :test_xml_output
+  def test_should_impose_childless_html_tags_in_html
+    process :test_xml_output, params: { response_as: "text/html" }
 
-    begin
-      $stderr = StringIO.new
-      assert_select 'area' #This will cause a warning if content is processed as HTML
-      $stderr.rewind && err = $stderr.read
-    ensure
-      $stderr = STDERR
-    end
+    # <area> auto-closes, so the <p> becomes a sibling
+    assert_select "root > area + p"
+  end
+
+  def test_should_not_impose_childless_html_tags_in_xml
+    process :test_xml_output, params: { response_as: "application/xml" }
 
-    assert err.empty?
+    # <area> is not special, so the <p> is its child
+    assert_select "root > area > p"
   end
 
   def test_assert_generates
-    assert_generates 'controller/action/5', controller: 'controller', action: 'action', id: '5'
-    assert_generates 'controller/action/7', { id: "7" }, { controller: "controller", action: "action" }
-    assert_generates 'controller/action/5', { controller: "controller", action: "action", id: "5", name: "bob" }, {}, { name: "bob" }
-    assert_generates 'controller/action/7', { id: "7", name: "bob" }, { controller: "controller", action: "action" }, { name: "bob" }
-    assert_generates 'controller/action/7', { id: "7" }, { controller: "controller", action: "action", name: "bob" }, {}
+    assert_generates "controller/action/5", controller: "controller", action: "action", id: "5"
+    assert_generates "controller/action/7", { id: "7" }, { controller: "controller", action: "action" }
+    assert_generates "controller/action/5", { controller: "controller", action: "action", id: "5", name: "bob" }, {}, { name: "bob" }
+    assert_generates "controller/action/7", { id: "7", name: "bob" }, { controller: "controller", action: "action" }, { name: "bob" }
+    assert_generates "controller/action/7", { id: "7" }, { controller: "controller", action: "action", name: "bob" }, {}
   end
 
   def test_assert_routing
-    assert_routing 'content', controller: 'content', action: 'index'
+    assert_routing "content", controller: "content", action: "index"
   end
 
   def test_assert_routing_with_method
     with_routing do |set|
       set.draw { resources(:content) }
-      assert_routing({ method: 'post', path: 'content' }, { controller: 'content', action: 'create' })
+      assert_routing({ method: "post", path: "content" }, { controller: "content", action: "create" })
     end
   end
 
@@ -476,85 +413,71 @@ XML
     with_routing do |set|
       set.draw do
         namespace :admin do
-          get 'user' => 'user#index'
+          get "user" => "user#index"
         end
       end
 
-      assert_routing 'admin/user', controller: 'admin/user', action: 'index'
+      assert_routing "admin/user", controller: "admin/user", action: "index"
     end
   end
 
   def test_assert_routing_with_glob
     with_routing do |set|
-      set.draw { get('*path' => "pages#show") }
-      assert_routing('/company/about', { controller: 'pages', action: 'show', path: 'company/about' })
+      set.draw { get("*path" => "pages#show") }
+      assert_routing("/company/about", controller: "pages", action: "show", path: "company/about")
     end
   end
 
-  def test_deprecated_params_passing
-    assert_deprecated {
-      get :test_params, page: { name: "Page name", month: '4', year: '2004', day: '6' }
-    }
-    parsed_params = ::JSON.parse(@response.body)
-    assert_equal(
-      {
-        'controller' => 'test_case_test/test', 'action' => 'test_params',
-        'page' => { 'name' => "Page name", 'month' => '4', 'year' => '2004', 'day' => '6' }
-      },
-      parsed_params
-    )
-  end
-
   def test_params_passing
     get :test_params, params: {
       page: {
         name: "Page name",
-        month: '4',
-        year: '2004',
-        day: '6'
+        month: "4",
+        year: "2004",
+        day: "6"
       }
     }
     parsed_params = ::JSON.parse(@response.body)
     assert_equal(
       {
-        'controller' => 'test_case_test/test', 'action' => 'test_params',
-        'page' => { 'name' => "Page name", 'month' => '4', 'year' => '2004', 'day' => '6' }
+        "controller" => "test_case_test/test", "action" => "test_params",
+        "page" => { "name" => "Page name", "month" => "4", "year" => "2004", "day" => "6" }
       },
       parsed_params
     )
   end
 
   def test_query_param_named_action
-    get :test_query_parameters, params: {action: 'foobar'}
+    get :test_query_parameters, params: { action: "foobar" }
     parsed_params = JSON.parse(@response.body)
-    assert_equal({'action' => 'foobar'}, parsed_params)
+    assert_equal({ "action" => "foobar" }, parsed_params)
   end
 
   def test_request_param_named_action
-    post :test_request_parameters, params: {action: 'foobar'}
+    post :test_request_parameters, params: { action: "foobar" }
     parsed_params = eval(@response.body)
-    assert_equal({'action' => 'foobar'}, parsed_params)
+    assert_equal({ "action" => "foobar" }, parsed_params)
   end
 
   def test_kwarg_params_passing_with_session_and_flash
     get :test_params, params: {
       page: {
         name: "Page name",
-        month: '4',
-        year: '2004',
-        day: '6'
+        month: "4",
+        year: "2004",
+        day: "6"
       }
-    }, session: { 'foo' => 'bar' }, flash: { notice: 'created' }
+    }, session: { "foo" => "bar" }, flash: { notice: "created" }
 
     parsed_params = ::JSON.parse(@response.body)
     assert_equal(
-      {'controller' => 'test_case_test/test', 'action' => 'test_params',
-       'page' => {'name' => "Page name", 'month' => '4', 'year' => '2004', 'day' => '6'}},
+      { "controller" => "test_case_test/test", "action" => "test_params",
+       "page" => { "name" => "Page name", "month" => "4", "year" => "2004", "day" => "6" } },
       parsed_params
     )
 
-    assert_equal 'bar', session[:foo]
-    assert_equal 'created', flash[:notice]
+    assert_equal "bar", session[:foo]
+    assert_equal "created", flash[:notice]
   end
 
   def test_params_passing_with_integer
@@ -563,38 +486,28 @@ XML
     }
     parsed_params = ::JSON.parse(@response.body)
     assert_equal(
-      {'controller' => 'test_case_test/test', 'action' => 'test_params',
-       'page' => {'name' => "Page name", 'month' => '4', 'year' => '2004', 'day' => '6'}},
+      { "controller" => "test_case_test/test", "action" => "test_params",
+       "page" => { "name" => "Page name", "month" => "4", "year" => "2004", "day" => "6" } },
       parsed_params
     )
   end
 
   def test_params_passing_with_integers_when_not_html_request
-    get :test_params, params: { format: 'json', count: 999 }
+    get :test_params, params: { format: "json", count: 999 }
     parsed_params = ::JSON.parse(@response.body)
     assert_equal(
-      {'controller' => 'test_case_test/test', 'action' => 'test_params',
-       'format' => 'json', 'count' => '999' },
+      { "controller" => "test_case_test/test", "action" => "test_params",
+       "format" => "json", "count" => "999" },
       parsed_params
     )
   end
 
   def test_params_passing_path_parameter_is_string_when_not_html_request
-    get :test_params, params: { format: 'json', id: 1 }
+    get :test_params, params: { format: "json", id: 1 }
     parsed_params = ::JSON.parse(@response.body)
     assert_equal(
-      {'controller' => 'test_case_test/test', 'action' => 'test_params',
-       'format' => 'json', 'id' => '1' },
-      parsed_params
-    )
-  end
-
-  def test_deprecated_params_passing_path_parameter_is_string_when_not_html_request
-    assert_deprecated { get :test_params, format: 'json', id: 1 }
-    parsed_params = ::JSON.parse(@response.body)
-    assert_equal(
-      {'controller' => 'test_case_test/test', 'action' => 'test_params',
-       'format' => 'json', 'id' => '1' },
+      { "controller" => "test_case_test/test", "action" => "test_params",
+       "format" => "json", "id" => "1" },
       parsed_params
     )
   end
@@ -602,13 +515,13 @@ XML
   def test_params_passing_with_frozen_values
     assert_nothing_raised do
       get :test_params, params: {
-        frozen: 'icy'.freeze, frozens: ['icy'.freeze].freeze, deepfreeze: { frozen: 'icy'.freeze }.freeze
+        frozen: "icy".freeze, frozens: ["icy".freeze].freeze, deepfreeze: { frozen: "icy".freeze }.freeze
       }
     end
     parsed_params = ::JSON.parse(@response.body)
     assert_equal(
-      {'controller' => 'test_case_test/test', 'action' => 'test_params',
-       'frozen' => 'icy', 'frozens' => ['icy'], 'deepfreeze' => { 'frozen' => 'icy' }},
+      { "controller" => "test_case_test/test", "action" => "test_params",
+       "frozen" => "icy", "frozens" => ["icy"], "deepfreeze" => { "frozen" => "icy" } },
       parsed_params
     )
   end
@@ -620,8 +533,8 @@ XML
   end
 
   test "set additional HTTP headers" do
-    @request.headers['Referer'] = "http://nohost.com/home"
-    @request.headers['Content-Type'] = "application/rss+xml"
+    @request.headers["Referer"] = "http://nohost.com/home"
+    @request.headers["Content-Type"] = "application/rss+xml"
     get :test_headers
     parsed_env = ActiveSupport::JSON.decode(@response.body)
     assert_equal "http://nohost.com/home", parsed_env["HTTP_REFERER"]
@@ -629,36 +542,50 @@ XML
   end
 
   test "set additional env variables" do
-    @request.headers['HTTP_REFERER'] = "http://example.com/about"
-    @request.headers['CONTENT_TYPE'] = "application/json"
+    @request.headers["HTTP_REFERER"] = "http://example.com/about"
+    @request.headers["CONTENT_TYPE"] = "application/json"
     get :test_headers
     parsed_env = ActiveSupport::JSON.decode(@response.body)
     assert_equal "http://example.com/about", parsed_env["HTTP_REFERER"]
     assert_equal "application/json", parsed_env["CONTENT_TYPE"]
   end
 
+  def test_using_as_json_sets_request_content_type_to_json
+    post :render_body, params: { bool_value: true, str_value: "string", num_value: 2 }, as: :json
+
+    assert_equal "application/json", @request.headers["CONTENT_TYPE"]
+    assert_equal true, @request.request_parameters[:bool_value]
+    assert_equal "string", @request.request_parameters[:str_value]
+    assert_equal 2, @request.request_parameters[:num_value]
+  end
+
+  def test_using_as_json_sets_format_json
+    post :render_body, params: { bool_value: true, str_value: "string", num_value: 2 }, as: :json
+    assert_equal "json", @request.format
+  end
+
   def test_mutating_content_type_headers_for_plain_text_files_sets_the_header
-    @request.headers['Content-Type'] = 'text/plain'
-    post :render_body, params: { name: 'foo.txt' }
+    @request.headers["Content-Type"] = "text/plain"
+    post :render_body, params: { name: "foo.txt" }
 
-    assert_equal 'text/plain', @request.headers['Content-type']
-    assert_equal 'foo.txt', @request.request_parameters[:name]
-    assert_equal 'render_body', @request.path_parameters[:action]
+    assert_equal "text/plain", @request.headers["Content-type"]
+    assert_equal "foo.txt", @request.request_parameters[:name]
+    assert_equal "render_body", @request.path_parameters[:action]
   end
 
   def test_mutating_content_type_headers_for_html_files_sets_the_header
-    @request.headers['Content-Type'] = 'text/html'
-    post :render_body, params: { name: 'foo.html' }
+    @request.headers["Content-Type"] = "text/html"
+    post :render_body, params: { name: "foo.html" }
 
-    assert_equal 'text/html', @request.headers['Content-type']
-    assert_equal 'foo.html', @request.request_parameters[:name]
-    assert_equal 'render_body', @request.path_parameters[:action]
+    assert_equal "text/html", @request.headers["Content-type"]
+    assert_equal "foo.html", @request.request_parameters[:name]
+    assert_equal "render_body", @request.path_parameters[:action]
   end
 
   def test_mutating_content_type_headers_for_non_registered_mime_type_raises_an_error
     assert_raises(RuntimeError) do
-      @request.headers['Content-Type'] = 'type/fake'
-      post :render_body, params: { name: 'foo.fake' }
+      @request.headers["Content-Type"] = "type/fake"
+      post :render_body, params: { name: "foo.fake" }
     end
   end
 
@@ -669,24 +596,19 @@ XML
     assert_kind_of String, @request.path_parameters[:id]
   end
 
-  def test_deprecared_id_converted_to_string
-    assert_deprecated { get :test_params, id: 20, foo: Object.new}
-    assert_kind_of String, @request.path_parameters[:id]
-  end
-
   def test_array_path_parameter_handled_properly
     with_routing do |set|
       set.draw do
-        get 'file/*path', to: 'test_case_test/test#test_params'
+        get "file/*path", to: "test_case_test/test#test_params"
 
         ActiveSupport::Deprecation.silence do
-          get ':controller/:action'
+          get ":controller/:action"
         end
       end
 
-      get :test_params, params: { path: ['hello', 'world'] }
-      assert_equal ['hello', 'world'], @request.path_parameters[:path]
-      assert_equal 'hello/world', @request.path_parameters[:path].to_param
+      get :test_params, params: { path: ["hello", "world"] }
+      assert_equal ["hello", "world"], @request.path_parameters[:path]
+      assert_equal "hello/world", @request.path_parameters[:path].to_param
     end
   end
 
@@ -704,8 +626,8 @@ XML
     routes_id = @routes.object_id
 
     begin
-      with_routing { raise 'fail' }
-      fail 'Should not be here.'
+      with_routing { raise "fail" }
+      fail "Should not be here."
     rescue RuntimeError
     end
 
@@ -724,46 +646,23 @@ XML
 
   def test_header_properly_reset_after_remote_http_request
     get :test_params, xhr: true
-    assert_nil @request.env['HTTP_X_REQUESTED_WITH']
-    assert_nil @request.env['HTTP_ACCEPT']
-  end
-
-  def test_deprecated_xhr_with_params
-    assert_deprecated { xhr :get, :test_params, params: { id: 1 } }
-
-    assert_equal({"id"=>"1", "controller"=>"test_case_test/test", "action"=>"test_params"}, ::JSON.parse(@response.body))
+    assert_nil @request.env["HTTP_X_REQUESTED_WITH"]
+    assert_nil @request.env["HTTP_ACCEPT"]
   end
 
   def test_xhr_with_params
     get :test_params, params: { id: 1 }, xhr: true
 
-    assert_equal({"id"=>"1", "controller"=>"test_case_test/test", "action"=>"test_params"}, ::JSON.parse(@response.body))
+    assert_equal({ "id" => "1", "controller" => "test_case_test/test", "action" => "test_params" }, ::JSON.parse(@response.body))
   end
 
   def test_xhr_with_session
     get :set_session, xhr: true
 
-    assert_equal 'A wonder', session['string'], "A value stored in the session should be available by string key"
-    assert_equal 'A wonder', session[:string], "Test session hash should allow indifferent access"
-    assert_equal 'it works', session['symbol'], "Test session hash should allow indifferent access"
-    assert_equal 'it works', session[:symbol], "Test session hash should allow indifferent access"
-  end
-
-  def test_deprecated_xhr_with_session
-    assert_deprecated { xhr :get, :set_session }
-
-    assert_equal 'A wonder', session['string'], "A value stored in the session should be available by string key"
-    assert_equal 'A wonder', session[:string], "Test session hash should allow indifferent access"
-    assert_equal 'it works', session['symbol'], "Test session hash should allow indifferent access"
-    assert_equal 'it works', session[:symbol], "Test session hash should allow indifferent access"
-  end
-
-  def test_deprecated_params_reset_between_post_requests
-    assert_deprecated { post :no_op, foo: "bar" }
-    assert_equal "bar", @request.params[:foo]
-
-    post :no_op
-    assert @request.params[:foo].blank?
+    assert_equal "A wonder", session["string"], "A value stored in the session should be available by string key"
+    assert_equal "A wonder", session[:string], "Test session hash should allow indifferent access"
+    assert_equal "it works", session["symbol"], "Test session hash should allow indifferent access"
+    assert_equal "it works", session[:symbol], "Test session hash should allow indifferent access"
   end
 
   def test_params_reset_between_post_requests
@@ -782,6 +681,11 @@ XML
     assert_equal "baz", @request.filtered_parameters[:foo]
   end
 
+  def test_path_is_kept_after_the_request
+    get :test_params, params: { id: "foo" }
+    assert_equal "/test_case_test/test/test_params/foo", @request.path
+  end
+
   def test_path_params_reset_between_request
     get :test_params, params: { id: "foo" }
     assert_equal "foo", @request.path_parameters[:id]
@@ -804,54 +708,62 @@ XML
   end
 
   def test_request_format
-    get :test_format, params: { format: 'html' }
-    assert_equal 'text/html', @response.body
+    get :test_format, params: { format: "html" }
+    assert_equal "text/html", @response.body
 
-    get :test_format, params: { format: 'json' }
-    assert_equal 'application/json', @response.body
+    get :test_format, params: { format: "json" }
+    assert_equal "application/json", @response.body
 
-    get :test_format, params: { format: 'xml' }
-    assert_equal 'application/xml', @response.body
+    get :test_format, params: { format: "xml" }
+    assert_equal "application/xml", @response.body
 
     get :test_format
-    assert_equal 'text/html', @response.body
+    assert_equal "text/html", @response.body
   end
 
   def test_request_format_kwarg
-    get :test_format, format: 'html'
-    assert_equal 'text/html', @response.body
+    get :test_format, format: "html"
+    assert_equal "text/html", @response.body
 
-    get :test_format, format: 'json'
-    assert_equal 'application/json', @response.body
+    get :test_format, format: "json"
+    assert_equal "application/json", @response.body
 
-    get :test_format, format: 'xml'
-    assert_equal 'application/xml', @response.body
+    get :test_format, format: "xml"
+    assert_equal "application/xml", @response.body
 
     get :test_format
-    assert_equal 'text/html', @response.body
+    assert_equal "text/html", @response.body
   end
 
   def test_request_format_kwarg_overrides_params
-    get :test_format, format: 'json', params: { format: 'html' }
-    assert_equal 'application/json', @response.body
+    get :test_format, format: "json", params: { format: "html" }
+    assert_equal "application/json", @response.body
   end
 
   def test_should_have_knowledge_of_client_side_cookie_state_even_if_they_are_not_set
-    cookies['foo'] = 'bar'
+    cookies["foo"] = "bar"
     get :no_op
-    assert_equal 'bar', cookies['foo']
+    assert_equal "bar", cookies["foo"]
   end
 
   def test_cookies_should_be_escaped_properly
-    cookies['foo'] = '+'
+    cookies["foo"] = "+"
     get :render_cookie
-    assert_equal '+', @response.body
+    assert_equal "+", @response.body
   end
 
   def test_should_detect_if_cookie_is_deleted
-    cookies['foo'] = 'bar'
+    cookies["foo"] = "bar"
     get :delete_cookie
-    assert_nil cookies['foo']
+    assert_nil cookies["foo"]
+  end
+
+  def test_multiple_mixed_method_process_should_scrub_rack_input
+    post :test_params, params: { id: 1, foo: "an foo" }
+    assert_equal({ "id" => "1", "foo" => "an foo", "controller" => "test_case_test/test", "action" => "test_params" }, ::JSON.parse(@response.body))
+
+    get :test_params, params: { bar: "an bar" }
+    assert_equal({ "bar" => "an bar", "controller" => "test_case_test/test", "action" => "test_params" }, ::JSON.parse(@response.body))
   end
 
   %w(controller response request).each do |variable|
@@ -870,15 +782,15 @@ XML
     end
   end
 
-  FILES_DIR = File.dirname(__FILE__) + '/../fixtures/multipart'
+  FILES_DIR = File.expand_path("../fixtures/multipart", __dir__)
 
-  READ_BINARY = 'rb:binary'
-  READ_PLAIN = 'r:binary'
+  READ_BINARY = "rb:binary"
+  READ_PLAIN = "r:binary"
 
   def test_test_uploaded_file
-    filename = 'mona_lisa.jpg'
+    filename = "ruby_on_rails.jpg"
     path = "#{FILES_DIR}/#{filename}"
-    content_type = 'image/png'
+    content_type = "image/png"
     expected = File.read(path)
     expected.force_encoding(Encoding::BINARY)
 
@@ -891,20 +803,19 @@ XML
     new_content_type = "new content_type"
     file.content_type = new_content_type
     assert_equal new_content_type, file.content_type
-
   end
 
   def test_fixture_path_is_accessed_from_self_instead_of_active_support_test_case
     TestCaseTest.stub :fixture_path, FILES_DIR do
-      uploaded_file = fixture_file_upload('/mona_lisa.jpg', 'image/png')
-      assert_equal File.open("#{FILES_DIR}/mona_lisa.jpg", READ_PLAIN).read, uploaded_file.read
+      uploaded_file = fixture_file_upload("/ruby_on_rails.jpg", "image/png")
+      assert_equal File.open("#{FILES_DIR}/ruby_on_rails.jpg", READ_PLAIN).read, uploaded_file.read
     end
   end
 
   def test_test_uploaded_file_with_binary
-    filename = 'mona_lisa.jpg'
+    filename = "ruby_on_rails.jpg"
     path = "#{FILES_DIR}/#{filename}"
-    content_type = 'image/png'
+    content_type = "image/png"
 
     binary_uploaded_file = Rack::Test::UploadedFile.new(path, content_type, :binary)
     assert_equal File.open(path, READ_BINARY).read, binary_uploaded_file.read
@@ -914,9 +825,9 @@ XML
   end
 
   def test_fixture_file_upload_with_binary
-    filename = 'mona_lisa.jpg'
+    filename = "ruby_on_rails.jpg"
     path = "#{FILES_DIR}/#{filename}"
-    content_type = 'image/jpg'
+    content_type = "image/jpg"
 
     binary_file_upload = fixture_file_upload(path, content_type, :binary)
     assert_equal File.open(path, READ_BINARY).read, binary_file_upload.read
@@ -926,50 +837,48 @@ XML
   end
 
   def test_fixture_file_upload_should_be_able_access_to_tempfile
-    file = fixture_file_upload(FILES_DIR + "/mona_lisa.jpg", "image/jpg")
+    file = fixture_file_upload(FILES_DIR + "/ruby_on_rails.jpg", "image/jpg")
     assert file.respond_to?(:tempfile), "expected tempfile should respond on fixture file object, got nothing"
   end
 
   def test_fixture_file_upload
     post :test_file_upload,
       params: {
-        file: fixture_file_upload(FILES_DIR + "/mona_lisa.jpg", "image/jpg")
+        file: fixture_file_upload(FILES_DIR + "/ruby_on_rails.jpg", "image/jpg")
       }
-    assert_equal '159528', @response.body
+    assert_equal "45142", @response.body
   end
 
   def test_fixture_file_upload_relative_to_fixture_path
     TestCaseTest.stub :fixture_path, FILES_DIR do
-      uploaded_file = fixture_file_upload("mona_lisa.jpg", "image/jpg")
-      assert_equal File.open("#{FILES_DIR}/mona_lisa.jpg", READ_PLAIN).read, uploaded_file.read
+      uploaded_file = fixture_file_upload("ruby_on_rails.jpg", "image/jpg")
+      assert_equal File.open("#{FILES_DIR}/ruby_on_rails.jpg", READ_PLAIN).read, uploaded_file.read
     end
   end
 
-  def test_fixture_file_upload_ignores_nil_fixture_path
-    uploaded_file = fixture_file_upload("#{FILES_DIR}/mona_lisa.jpg", "image/jpg")
-    assert_equal File.open("#{FILES_DIR}/mona_lisa.jpg", READ_PLAIN).read, uploaded_file.read
+  def test_fixture_file_upload_ignores_fixture_path_given_full_path
+    TestCaseTest.stub :fixture_path, __dir__ do
+      uploaded_file = fixture_file_upload("#{FILES_DIR}/ruby_on_rails.jpg", "image/jpg")
+      assert_equal File.open("#{FILES_DIR}/ruby_on_rails.jpg", READ_PLAIN).read, uploaded_file.read
+    end
   end
 
-  def test_deprecated_action_dispatch_uploaded_file_upload
-    filename = 'mona_lisa.jpg'
-    path = "#{FILES_DIR}/#{filename}"
-    assert_deprecated {
-      post :test_file_upload, file: Rack::Test::UploadedFile.new(path, "image/jpg", true)
-    }
-    assert_equal '159528', @response.body
+  def test_fixture_file_upload_ignores_nil_fixture_path
+    uploaded_file = fixture_file_upload("#{FILES_DIR}/ruby_on_rails.jpg", "image/jpg")
+    assert_equal File.open("#{FILES_DIR}/ruby_on_rails.jpg", READ_PLAIN).read, uploaded_file.read
   end
 
   def test_action_dispatch_uploaded_file_upload
-    filename = 'mona_lisa.jpg'
+    filename = "ruby_on_rails.jpg"
     path = "#{FILES_DIR}/#{filename}"
     post :test_file_upload, params: {
       file: Rack::Test::UploadedFile.new(path, "image/jpg", true)
     }
-    assert_equal '159528', @response.body
+    assert_equal "45142", @response.body
   end
 
   def test_test_uploaded_file_exception_when_file_doesnt_exist
-    assert_raise(RuntimeError) { Rack::Test::UploadedFile.new('non_existent_file') }
+    assert_raise(RuntimeError) { Rack::Test::UploadedFile.new("non_existent_file") }
   end
 
   def test_redirect_url_only_cares_about_location_header
@@ -977,12 +886,12 @@ XML
     assert_response :created
 
     # Redirect url doesn't care that it wasn't a :redirect response.
-    assert_equal 'created resource', @response.redirect_url
+    assert_equal "/resource", @response.redirect_url
     assert_equal @response.redirect_url, redirect_to_url
 
     # Must be a :redirect response.
     assert_raise(ActiveSupport::TestCase::Assertion) do
-      assert_redirected_to 'created resource'
+      assert_redirected_to "/resource"
     end
   end
 
@@ -996,12 +905,12 @@ XML
     assert_raise(RuntimeError) do
       process :boom,
         method: "GET",
-        params: { q: 'test1' }
+        params: { q: "test1" }
     end
 
     process :test_query_string,
       method: "GET",
-      params: { q: 'test2' }
+      params: { q: "test2" }
 
     assert_equal "q=test2", @response.body
   end
@@ -1011,7 +920,7 @@ class ResponseDefaultHeadersTest < ActionController::TestCase
   class TestController < ActionController::Base
     def remove_header
       headers.delete params[:header]
-      head :ok, 'C' => '3'
+      head :ok, "C" => "3"
     end
 
     # Render a head response, but don't touch default headers
@@ -1022,7 +931,7 @@ class ResponseDefaultHeadersTest < ActionController::TestCase
 
   def before_setup
     @original = ActionDispatch::Response.default_headers
-    @defaults = { 'A' => '1', 'B' => '2' }
+    @defaults = { "A" => "1", "B" => "2" }
     ActionDispatch::Response.default_headers = @defaults
     super
   end
@@ -1034,11 +943,11 @@ class ResponseDefaultHeadersTest < ActionController::TestCase
   def setup
     super
     @controller = TestController.new
-    @request.env['PATH_INFO'] = nil
+    @request.env["PATH_INFO"] = nil
     @routes = ActionDispatch::Routing::RouteSet.new.tap do |r|
       r.draw do
         ActiveSupport::Deprecation.silence do
-          get ':controller(/:action(/:id))'
+          get ":controller(/:action(/:id))"
         end
       end
     end
@@ -1048,18 +957,18 @@ class ResponseDefaultHeadersTest < ActionController::TestCase
     get :leave_alone
 
     # Response headers start out with the defaults
-    assert_equal @defaults.merge('Content-Type' => 'text/html'), response.headers
+    assert_equal @defaults.merge("Content-Type" => "text/html"), response.headers
   end
 
   test "response deletes a default header" do
-    get :remove_header, params: { header: 'A' }
+    get :remove_header, params: { header: "A" }
     assert_response :ok
 
     # After a request, the response in the test case doesn't have the
     # defaults merged on top again.
-    assert_not_includes response.headers, 'A'
-    assert_includes response.headers, 'B'
-    assert_includes response.headers, 'C'
+    assert_not_includes response.headers, "A"
+    assert_includes response.headers, "B"
+    assert_includes response.headers, "C"
   end
 end
 
@@ -1068,13 +977,13 @@ module EngineControllerTests
     isolate_namespace EngineControllerTests
 
     routes.draw do
-      get '/' => 'bar#index'
+      get "/" => "bar#index"
     end
   end
 
   class BarController < ActionController::Base
     def index
-      render plain: 'bar'
+      render plain: "bar"
     end
   end
 
@@ -1083,7 +992,7 @@ module EngineControllerTests
 
     def test_engine_controller_route
       get :index
-      assert_equal @response.body, 'bar'
+      assert_equal @response.body, "bar"
     end
   end
 
@@ -1096,7 +1005,7 @@ module EngineControllerTests
 
     def test_engine_controller_route
       get :index
-      assert_equal @response.body, 'bar'
+      assert_equal @response.body, "bar"
     end
   end
 end
@@ -1137,7 +1046,7 @@ class CrazySymbolNameTest < ActionController::TestCase
 end
 
 class CrazyStringNameTest < ActionController::TestCase
-  tests 'content'
+  tests "content"
 
   def test_set_controller_class_using_string
     assert_equal ContentController, self.class.controller_class
@@ -1150,8 +1059,8 @@ class NamedRoutesControllerTest < ActionController::TestCase
   def test_should_be_able_to_use_named_routes_before_a_request_is_done
     with_routing do |set|
       set.draw { resources :contents }
-      assert_equal 'http://test.host/contents/new', new_content_url
-      assert_equal 'http://test.host/contents/1', content_url(id: 1)
+      assert_equal "http://test.host/contents/new", new_content_url
+      assert_equal "http://test.host/contents/1", content_url(id: 1)
     end
   end
 end
@@ -1167,7 +1076,7 @@ class AnonymousControllerTest < ActionController::TestCase
     @routes = ActionDispatch::Routing::RouteSet.new.tap do |r|
       r.draw do
         ActiveSupport::Deprecation.silence do
-          get ':controller(/:action(/:id))'
+          get ":controller(/:action(/:id))"
         end
       end
     end
@@ -1175,7 +1084,7 @@ class AnonymousControllerTest < ActionController::TestCase
 
   def test_controller_name
     get :index
-    assert_equal 'anonymous', @response.body
+    assert_equal "anonymous", @response.body
   end
 end
 
@@ -1193,19 +1102,19 @@ class RoutingDefaultsTest < ActionController::TestCase
 
     @routes = ActionDispatch::Routing::RouteSet.new.tap do |r|
       r.draw do
-        get '/posts/:id', to: 'anonymous#post', bucket_type: 'post'
-        get '/projects/:id', to: 'anonymous#project', defaults: { bucket_type: 'project' }
+        get "/posts/:id", to: "anonymous#post", bucket_type: "post"
+        get "/projects/:id", to: "anonymous#project", defaults: { bucket_type: "project" }
       end
     end
   end
 
   def test_route_option_can_be_passed_via_process
-    get :post, params: { id: 1, bucket_type: 'post'}
-    assert_equal '/posts/1', @response.body
+    get :post, params: { id: 1, bucket_type: "post" }
+    assert_equal "/posts/1", @response.body
   end
 
   def test_route_default_is_not_required_for_building_request_uri
     get :project, params: { id: 2 }
-    assert_equal '/projects/2', @response.body
+    assert_equal "/projects/2", @response.body
   end
 end
diff --git a/actionpack/test/controller/url_for_integration_test.rb b/actionpack/test/controller/url_for_integration_test.rb
index a6ca5fc868..a1521da702 100644
--- a/actionpack/test/controller/url_for_integration_test.rb
+++ b/actionpack/test/controller/url_for_integration_test.rb
@@ -1,6 +1,8 @@
-require 'abstract_unit'
-require 'controller/fake_controllers'
-require 'active_support/core_ext/object/with_options'
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "controller/fake_controllers"
+require "active_support/core_ext/object/with_options"
 
 module ActionPack
   class URLForIntegrationTest < ActiveSupport::TestCase
@@ -14,54 +16,53 @@ module ActionPack
         resources :users, :posts
       end
 
-      namespace 'api' do
-        root :to => 'users#index'
+      namespace "api" do
+        root to: "users#index"
       end
 
-      get '/blog(/:year(/:month(/:day)))' => 'posts#show_date',
+      get "/blog(/:year(/:month(/:day)))" => "posts#show_date",
         :constraints => {
-          :year => /(19|20)\d\d/,
-          :month => /[01]?\d/,
-          :day => /[0-3]?\d/
+          year: /(19|20)\d\d/,
+          month: /[01]?\d/,
+          day: /[0-3]?\d/
         },
         :day => nil,
         :month => nil
 
-      get 'archive/:year', :controller => 'archive', :action => 'index',
-        :defaults => { :year => nil },
-        :constraints => { :year => /\d{4}/ },
-        :as => "blog"
+      get "archive/:year", controller: "archive", action: "index",
+        defaults: { year: nil },
+        constraints: { year: /\d{4}/ },
+        as: "blog"
 
       resources :people
-      #match 'legacy/people' => "people#index", :legacy => "true"
-
-      get 'symbols', :controller => :symbols, :action => :show, :name => :as_symbol
-      get 'id_default(/:id)' => "foo#id_default", :id => 1
-      match 'get_or_post' => "foo#get_or_post", :via => [:get, :post]
-      get 'optional/:optional' => "posts#index"
-      get 'projects/:project_id' => "project#index", :as => "project"
-      get 'clients' => "projects#index"
-
-      get 'ignorecase/geocode/:postalcode' => 'geocode#show', :postalcode => /hx\d\d-\d[a-z]{2}/i
-      get 'extended/geocode/:postalcode' => 'geocode#show',:constraints => {
-        :postalcode => /# Postcode format
+
+      get "symbols", controller: :symbols, action: :show, name: :as_symbol
+      get "id_default(/:id)" => "foo#id_default", :id => 1
+      match "get_or_post" => "foo#get_or_post", :via => [:get, :post]
+      get "optional/:optional" => "posts#index"
+      get "projects/:project_id" => "project#index", :as => "project"
+      get "clients" => "projects#index"
+
+      get "ignorecase/geocode/:postalcode" => "geocode#show", :postalcode => /hx\d\d-\d[a-z]{2}/i
+      get "extended/geocode/:postalcode" => "geocode#show", :constraints => {
+        postalcode: /# Postcode format
         \d{5} #Prefix
         (-\d{4})? #Suffix
         /x
       }, :as => "geocode"
 
-      get 'news(.:format)' => "news#index"
+      get "news(.:format)" => "news#index"
 
       ActiveSupport::Deprecation.silence {
-        get 'comment/:id(/:action)' => "comments#show"
-        get 'ws/:controller(/:action(/:id))', :ws => true
-        get 'account(/:action)' => "account#subscription"
-        get 'pages/:page_id/:controller(/:action(/:id))'
-        get ':controller/ping', :action => 'ping'
-        get ':controller(/:action(/:id))(.:format)'
+        get "comment/:id(/:action)" => "comments#show"
+        get "ws/:controller(/:action(/:id))", ws: true
+        get "account(/:action)" => "account#subscription"
+        get "pages/:page_id/:controller(/:action(/:id))"
+        get ":controller/ping", action: "ping"
+        get ":controller(/:action(/:id))(.:format)"
       }
 
-      root :to => "news#index"
+      root to: "news#index"
     }
 
     attr_reader :routes
@@ -73,111 +74,111 @@ module ActionPack
     end
 
     [
-      ['/admin/users',[ { :use_route => 'admin_users' }]],
-      ['/admin/users',[ { :controller => 'admin/users' }]],
-      ['/admin/users',[ { :controller => 'admin/users', :action => 'index' }]],
-      ['/admin/users',[ { :action => 'index' }, { :controller => 'admin/users', :action => 'index' }, '/admin/users']],
-      ['/admin/users',[ { :controller => 'users', :action => 'index' }, { :controller => 'admin/accounts', :action => 'show', :id => '1' }, '/admin/accounts/show/1']],
-      ['/people',[      { :controller => '/people', :action => 'index' }, {:controller=>"admin/accounts", :action=>"foo", :id=>"bar"}, '/admin/accounts/foo/bar']],
-
-      ['/admin/posts',[     { :controller => 'admin/posts' }]],
-      ['/admin/posts/new',[ { :controller => 'admin/posts', :action => 'new' }]],
-
-      ['/blog/2009',[     { :controller => 'posts', :action => 'show_date', :year => 2009 }]],
-      ['/blog/2009/1',[   { :controller => 'posts', :action => 'show_date', :year => 2009, :month => 1 }]],
-      ['/blog/2009/1/1',[ { :controller => 'posts', :action => 'show_date', :year => 2009, :month => 1, :day => 1 }]],
-
-      ['/archive/2010',[ { :controller => 'archive', :action => 'index', :year => '2010' }]],
-      ['/archive',[      { :controller => 'archive', :action => 'index' }]],
-      ['/archive?year=january',[ { :controller => 'archive', :action => 'index', :year => 'january' }]],
-
-      ['/people',[ { :controller => 'people', :action => 'index' }]],
-      ['/people',[ { :action => 'index' }, { :controller => 'people', :action => 'index' }, '/people']],
-      ['/people',[ { :action => 'index' }, { :controller => 'people', :action => 'show', :id => '1' }, '/people/show/1']],
-      ['/people',[ { :controller => 'people', :action => 'index' }, { :controller => 'people', :action => 'show', :id => '1' }, '/people/show/1']],
-      ['/people',[ {}, { :controller => 'people', :action => 'index' }, '/people']],
-      ['/people/1',[   { :controller => 'people', :action => 'show' }, { :controller => 'people', :action => 'show', :id => '1' }, '/people/show/1']],
-      ['/people/new',[ { :use_route => 'new_person' }]],
-      ['/people/new',[ { :controller => 'people', :action => 'new' }]],
-      ['/people/1',[   { :use_route => 'person', :id => '1' }]],
-      ['/people/1',[   { :controller => 'people', :action => 'show', :id => '1' }]],
-      ['/people/1.xml',[ { :controller => 'people', :action => 'show', :id => '1', :format => 'xml' }]],
-      ['/people/1',[ { :controller => 'people', :action => 'show', :id => 1 }]],
-      ['/people/1',[ { :controller => 'people', :action => 'show', :id => Model.new('1') }]],
-      ['/people/1',[ { :action => 'show', :id => '1' }, { :controller => 'people', :action => 'index' }, '/people']],
-      ['/people/1',[ { :action => 'show', :id => 1 }, { :controller => 'people', :action => 'show', :id => '1' }, '/people/show/1']],
-      ['/people',[   { :controller => 'people', :action => 'index' }, { :controller => 'people', :action => 'show', :id => '1' }, '/people/show/1']],
-      ['/people/1',[ {}, { :controller => 'people', :action => 'show', :id => '1' }, '/people/show/1']],
-      ['/people/1',[ { :controller => 'people', :action => 'show' }, { :controller => 'people', :action => 'index', :id => '1' }, '/people/index/1']],
-      ['/people/1/edit',[     { :controller => 'people', :action => 'edit', :id => '1' }]],
-      ['/people/1/edit.xml',[ { :controller => 'people', :action => 'edit', :id => '1', :format => 'xml' }]],
-      ['/people/1/edit',[     { :use_route => 'edit_person', :id => '1' }]],
-      ['/people/1?legacy=true',[ { :controller => 'people', :action => 'show', :id => '1', :legacy => 'true' }]],
-      ['/people?legacy=true',[   { :controller => 'people', :action => 'index', :legacy => 'true' }]],
-
-      ['/id_default/2',[ { :controller => 'foo', :action => 'id_default', :id => '2' }]],
-      ['/id_default',[   { :controller => 'foo', :action => 'id_default', :id => '1' }]],
-      ['/id_default',[   { :controller => 'foo', :action => 'id_default', :id => 1 }]],
-      ['/id_default',[   { :controller => 'foo', :action => 'id_default' }]],
-      ['/optional/bar',[ { :controller => 'posts', :action => 'index', :optional => 'bar' }]],
-      ['/posts',[ { :controller => 'posts', :action => 'index' }]],
-
-      ['/project',[    { :controller => 'project', :action => 'index' }]],
-      ['/projects/1',[ { :controller => 'project', :action => 'index', :project_id => '1' }]],
-      ['/projects/1',[ { :controller => 'project', :action => 'index'}, {:project_id => '1', :controller => 'project', :action => 'index' }, '/projects/1']],
-      ['/projects/1',[ { :use_route => 'project', :controller => 'project', :action => 'index', :project_id => '1' }]],
-      ['/projects/1',[ { :use_route => 'project', :controller => 'project', :action => 'index' }, { :controller => 'project', :action => 'index', :project_id => '1' }, '/projects/1']],
-
-      ['/clients',[ { :controller => 'projects', :action => 'index' }]],
-      ['/clients?project_id=1',[ { :controller => 'projects', :action => 'index', :project_id => '1' }]],
-      ['/clients',[ { :controller => 'projects', :action => 'index' }, { :project_id => '1', :controller => 'project', :action => 'index' }, '/projects/1']],
-
-      ['/comment/20',[   { :id => 20 }, { :controller => 'comments', :action => 'show' }, '/comments/show']],
-      ['/comment/20',[   { :controller => 'comments', :id => 20, :action => 'show' }]],
-      ['/comments/boo',[ { :controller => 'comments', :action => 'boo' }]],
-
-      ['/ws/posts/show/1',[ { :controller => 'posts', :action => 'show', :id => '1', :ws => true }]],
-      ['/ws/posts',[        { :controller => 'posts', :action => 'index', :ws => true }]],
-
-      ['/account',[         { :controller => 'account', :action => 'subscription' }]],
-      ['/account/billing',[ { :controller => 'account', :action => 'billing' }]],
-
-      ['/pages/1/notes/show/1',[ { :page_id => '1', :controller => 'notes', :action => 'show', :id => '1' }]],
-      ['/pages/1/notes/list',[   { :page_id => '1', :controller => 'notes', :action => 'list' }]],
-      ['/pages/1/notes',[ { :page_id => '1', :controller => 'notes', :action => 'index' }]],
-      ['/pages/1/notes',[ { :page_id => '1', :controller => 'notes' }]],
-      ['/notes',[         { :page_id => nil, :controller => 'notes' }]],
-      ['/notes',[         { :controller => 'notes' }]],
-      ['/notes/print',[   { :controller => 'notes', :action => 'print' }]],
-      ['/notes/print',[   {}, { :controller => 'notes', :action => 'print' }, '/notes/print']],
-
-      ['/notes/index/1',[ { :controller => 'notes' }, { :controller => 'notes', :action => 'index', :id => '1' }, '/notes/index/1']],
-      ['/notes/index/1',[ { :controller => 'notes' }, { :controller => 'notes', :id => '1', :action => 'index' }, '/notes/index/1']],
-      ['/notes/index/1',[ { :action => 'index' }, { :controller => 'notes', :id => '1', :action => 'index' }, '/notes/index/1']],
-      ['/notes/index/1',[ {}, { :controller => 'notes', :id => '1', :action => 'index' }, '/notes/index/1']],
-      ['/notes/show/1',[  {}, { :controller => 'notes', :action => 'show', :id => '1' }, '/notes/show/1']],
-      ['/posts',[      { :controller => 'posts' }, { :controller => 'notes', :action => 'show', :id => '1' }, '/notes/show/1']],
-      ['/notes/list',[ { :action => 'list' }, { :controller => 'notes', :action => 'show', :id => '1' }, '/notes/show/1']],
-
-      ['/posts/ping',[    { :controller => 'posts', :action => 'ping' }]],
-      ['/posts/show/1',[  { :controller => 'posts', :action => 'show', :id => '1' }]],
-      ['/posts/show/1',[  { :controller => 'posts', :action => 'show', :id => '1', :format => '' }]],
-      ['/posts',[         { :controller => 'posts' }]],
-      ['/posts',[         { :controller => 'posts', :action => 'index' }]],
-      ['/posts/create',[  { :action => 'create' }, {:day=>nil, :month=>nil, :controller=>"posts", :action=>"show_date"}, '/blog']],
-      ['/posts?foo=bar',[ { :controller => 'posts', :foo => 'bar' }]],
-      ['/posts?foo%5B%5D=bar&foo%5B%5D=baz', [{ :controller => 'posts', :foo => ['bar', 'baz'] }]],
-      ['/posts?page=2',  [{ :controller => 'posts', :page => 2 }]],
-      ['/posts?q%5Bfoo%5D%5Ba%5D=b', [{ :controller => 'posts', :q => { :foo => { :a => 'b'}} }]],
-
-      ['/news.rss', [{ :controller => 'news', :action => 'index', :format => 'rss' }]],
+      ["/admin/users", [ { use_route: "admin_users" }]],
+      ["/admin/users", [ { controller: "admin/users" }]],
+      ["/admin/users", [ { controller: "admin/users", action: "index" }]],
+      ["/admin/users", [ { action: "index" }, { controller: "admin/users", action: "index" }, "/admin/users"]],
+      ["/admin/users", [ { controller: "users", action: "index" }, { controller: "admin/accounts", action: "show", id: "1" }, "/admin/accounts/show/1"]],
+      ["/people", [      { controller: "/people", action: "index" }, { controller: "admin/accounts", action: "foo", id: "bar" }, "/admin/accounts/foo/bar"]],
+
+      ["/admin/posts", [     { controller: "admin/posts" }]],
+      ["/admin/posts/new", [ { controller: "admin/posts", action: "new" }]],
+
+      ["/blog/2009", [     { controller: "posts", action: "show_date", year: 2009 }]],
+      ["/blog/2009/1", [   { controller: "posts", action: "show_date", year: 2009, month: 1 }]],
+      ["/blog/2009/1/1", [ { controller: "posts", action: "show_date", year: 2009, month: 1, day: 1 }]],
+
+      ["/archive/2010", [ { controller: "archive", action: "index", year: "2010" }]],
+      ["/archive", [      { controller: "archive", action: "index" }]],
+      ["/archive?year=january", [ { controller: "archive", action: "index", year: "january" }]],
+
+      ["/people", [ { controller: "people", action: "index" }]],
+      ["/people", [ { action: "index" }, { controller: "people", action: "index" }, "/people"]],
+      ["/people", [ { action: "index" }, { controller: "people", action: "show", id: "1" }, "/people/show/1"]],
+      ["/people", [ { controller: "people", action: "index" }, { controller: "people", action: "show", id: "1" }, "/people/show/1"]],
+      ["/people", [ {}, { controller: "people", action: "index" }, "/people"]],
+      ["/people/1", [   { controller: "people", action: "show" }, { controller: "people", action: "show", id: "1" }, "/people/show/1"]],
+      ["/people/new", [ { use_route: "new_person" }]],
+      ["/people/new", [ { controller: "people", action: "new" }]],
+      ["/people/1", [   { use_route: "person", id: "1" }]],
+      ["/people/1", [   { controller: "people", action: "show", id: "1" }]],
+      ["/people/1.xml", [ { controller: "people", action: "show", id: "1", format: "xml" }]],
+      ["/people/1", [ { controller: "people", action: "show", id: 1 }]],
+      ["/people/1", [ { controller: "people", action: "show", id: Model.new("1") }]],
+      ["/people/1", [ { action: "show", id: "1" }, { controller: "people", action: "index" }, "/people"]],
+      ["/people/1", [ { action: "show", id: 1 }, { controller: "people", action: "show", id: "1" }, "/people/show/1"]],
+      ["/people", [   { controller: "people", action: "index" }, { controller: "people", action: "show", id: "1" }, "/people/show/1"]],
+      ["/people/1", [ {}, { controller: "people", action: "show", id: "1" }, "/people/show/1"]],
+      ["/people/1", [ { controller: "people", action: "show" }, { controller: "people", action: "index", id: "1" }, "/people/index/1"]],
+      ["/people/1/edit", [     { controller: "people", action: "edit", id: "1" }]],
+      ["/people/1/edit.xml", [ { controller: "people", action: "edit", id: "1", format: "xml" }]],
+      ["/people/1/edit", [     { use_route: "edit_person", id: "1" }]],
+      ["/people/1?legacy=true", [ { controller: "people", action: "show", id: "1", legacy: "true" }]],
+      ["/people?legacy=true", [   { controller: "people", action: "index", legacy: "true" }]],
+
+      ["/id_default/2", [ { controller: "foo", action: "id_default", id: "2" }]],
+      ["/id_default", [   { controller: "foo", action: "id_default", id: "1" }]],
+      ["/id_default", [   { controller: "foo", action: "id_default", id: 1 }]],
+      ["/id_default", [   { controller: "foo", action: "id_default" }]],
+      ["/optional/bar", [ { controller: "posts", action: "index", optional: "bar" }]],
+      ["/posts", [ { controller: "posts", action: "index" }]],
+
+      ["/project", [    { controller: "project", action: "index" }]],
+      ["/projects/1", [ { controller: "project", action: "index", project_id: "1" }]],
+      ["/projects/1", [ { controller: "project", action: "index" }, { project_id: "1", controller: "project", action: "index" }, "/projects/1"]],
+      ["/projects/1", [ { use_route: "project", controller: "project", action: "index", project_id: "1" }]],
+      ["/projects/1", [ { use_route: "project", controller: "project", action: "index" }, { controller: "project", action: "index", project_id: "1" }, "/projects/1"]],
+
+      ["/clients", [ { controller: "projects", action: "index" }]],
+      ["/clients?project_id=1", [ { controller: "projects", action: "index", project_id: "1" }]],
+      ["/clients", [ { controller: "projects", action: "index" }, { project_id: "1", controller: "project", action: "index" }, "/projects/1"]],
+
+      ["/comment/20", [   { id: 20 }, { controller: "comments", action: "show" }, "/comments/show"]],
+      ["/comment/20", [   { controller: "comments", id: 20, action: "show" }]],
+      ["/comments/boo", [ { controller: "comments", action: "boo" }]],
+
+      ["/ws/posts/show/1", [ { controller: "posts", action: "show", id: "1", ws: true }]],
+      ["/ws/posts", [        { controller: "posts", action: "index", ws: true }]],
+
+      ["/account", [         { controller: "account", action: "subscription" }]],
+      ["/account/billing", [ { controller: "account", action: "billing" }]],
+
+      ["/pages/1/notes/show/1", [ { page_id: "1", controller: "notes", action: "show", id: "1" }]],
+      ["/pages/1/notes/list", [   { page_id: "1", controller: "notes", action: "list" }]],
+      ["/pages/1/notes", [ { page_id: "1", controller: "notes", action: "index" }]],
+      ["/pages/1/notes", [ { page_id: "1", controller: "notes" }]],
+      ["/notes", [         { page_id: nil, controller: "notes" }]],
+      ["/notes", [         { controller: "notes" }]],
+      ["/notes/print", [   { controller: "notes", action: "print" }]],
+      ["/notes/print", [   {}, { controller: "notes", action: "print" }, "/notes/print"]],
+
+      ["/notes/index/1", [ { controller: "notes" }, { controller: "notes", action: "index", id: "1" }, "/notes/index/1"]],
+      ["/notes/index/1", [ { controller: "notes" }, { controller: "notes", id: "1", action: "index" }, "/notes/index/1"]],
+      ["/notes/index/1", [ { action: "index" }, { controller: "notes", id: "1", action: "index" }, "/notes/index/1"]],
+      ["/notes/index/1", [ {}, { controller: "notes", id: "1", action: "index" }, "/notes/index/1"]],
+      ["/notes/show/1", [  {}, { controller: "notes", action: "show", id: "1" }, "/notes/show/1"]],
+      ["/posts", [      { controller: "posts" }, { controller: "notes", action: "show", id: "1" }, "/notes/show/1"]],
+      ["/notes/list", [ { action: "list" }, { controller: "notes", action: "show", id: "1" }, "/notes/show/1"]],
+
+      ["/posts/ping", [    { controller: "posts", action: "ping" }]],
+      ["/posts/show/1", [  { controller: "posts", action: "show", id: "1" }]],
+      ["/posts/show/1", [  { controller: "posts", action: "show", id: "1", format: "" }]],
+      ["/posts", [         { controller: "posts" }]],
+      ["/posts", [         { controller: "posts", action: "index" }]],
+      ["/posts/create", [  { action: "create" }, { day: nil, month: nil, controller: "posts", action: "show_date" }, "/blog"]],
+      ["/posts?foo=bar", [ { controller: "posts", foo: "bar" }]],
+      ["/posts?foo%5B%5D=bar&foo%5B%5D=baz", [{ controller: "posts", foo: ["bar", "baz"] }]],
+      ["/posts?page=2",  [{ controller: "posts", page: 2 }]],
+      ["/posts?q%5Bfoo%5D%5Ba%5D=b", [{ controller: "posts", q: { foo: { a: "b" } } }]],
+
+      ["/news.rss", [{ controller: "news", action: "index", format: "rss" }]],
     ].each_with_index do |(url, params), i|
       if params.length > 1
         hash, path_params, route = *params
         hash[:only_path] = true
 
         define_method("test_#{url.gsub(/\W/, '_')}_#{i}") do
-          get URI('http://test.host' + route.to_s)
+          get URI("http://test.host" + route.to_s)
           assert_equal path_params, controller.request.path_parameters
           assert_equal url, controller.url_for(hash), params.inspect
         end
diff --git a/actionpack/test/controller/url_for_test.rb b/actionpack/test/controller/url_for_test.rb
index b4d2088c0a..cf11227897 100644
--- a/actionpack/test/controller/url_for_test.rb
+++ b/actionpack/test/controller/url_for_test.rb
@@ -1,4 +1,6 @@
-require 'abstract_unit'
+# frozen_string_literal: true
+
+require "abstract_unit"
 
 module AbstractController
   module Testing
@@ -7,7 +9,7 @@ module AbstractController
         include ActionDispatch::Routing::RouteSet.new.tap { |r|
           r.draw {
             ActiveSupport::Deprecation.silence {
-              get ':controller(/:action(/:id(.:format)))'
+              get ":controller(/:action(/:id(.:format)))"
             }
           }
         }.url_helpers
@@ -21,23 +23,23 @@ module AbstractController
         klass = Class.new {
           include ActionDispatch::Routing::RouteSet.new.tap { |r|
             r.draw {
-              get "/foo/(:bar/(:baz))/:zot", :as         => 'fun',
-                                             :controller => :articles,
-                                             :action     => :index
+              get "/foo/(:bar/(:baz))/:zot", as: "fun",
+                                             controller: :articles,
+                                             action: :index
             }
           }.url_helpers
-          self.default_url_options[:host] = 'example.com'
+          default_url_options[:host] = "example.com"
         }
 
-        path = klass.new.fun_path({:controller => :articles,
-                                   :baz        => "baz",
-                                   :zot        => "zot"})
+        path = klass.new.fun_path(controller: :articles,
+                                   baz: "baz",
+                                   zot: "zot")
         # :bar key isn't provided
-        assert_equal '/foo/zot', path
+        assert_equal "/foo/zot", path
       end
 
       def add_host!(app = W)
-        app.default_url_options[:host] = 'www.basecamphq.com'
+        app.default_url_options[:host] = "www.basecamphq.com"
       end
 
       def add_port!
@@ -45,166 +47,166 @@ module AbstractController
       end
 
       def add_numeric_host!
-        W.default_url_options[:host] = '127.0.0.1'
+        W.default_url_options[:host] = "127.0.0.1"
       end
 
       def test_exception_is_thrown_without_host
         assert_raise ArgumentError do
-          W.new.url_for :controller => 'c', :action => 'a', :id => 'i'
+          W.new.url_for controller: "c", action: "a", id: "i"
         end
       end
 
       def test_anchor
-        assert_equal('/c/a#anchor',
-          W.new.url_for(:only_path => true, :controller => 'c', :action => 'a', :anchor => 'anchor')
+        assert_equal("/c/a#anchor",
+          W.new.url_for(only_path: true, controller: "c", action: "a", anchor: "anchor")
         )
       end
 
       def test_nil_anchor
         assert_equal(
-          '/c/a',
-          W.new.url_for(only_path: true, controller: 'c', action: 'a', anchor: nil)
+          "/c/a",
+          W.new.url_for(only_path: true, controller: "c", action: "a", anchor: nil)
         )
       end
 
       def test_false_anchor
         assert_equal(
-          '/c/a',
-          W.new.url_for(only_path: true, controller: 'c', action: 'a', anchor: false)
+          "/c/a",
+          W.new.url_for(only_path: true, controller: "c", action: "a", anchor: false)
         )
       end
 
       def test_anchor_should_call_to_param
-        assert_equal('/c/a#anchor',
-          W.new.url_for(:only_path => true, :controller => 'c', :action => 'a', :anchor => Struct.new(:to_param).new('anchor'))
+        assert_equal("/c/a#anchor",
+          W.new.url_for(only_path: true, controller: "c", action: "a", anchor: Struct.new(:to_param).new("anchor"))
         )
       end
 
       def test_anchor_should_escape_unsafe_pchar
-        assert_equal('/c/a#%23anchor',
-          W.new.url_for(:only_path => true, :controller => 'c', :action => 'a', :anchor => Struct.new(:to_param).new('#anchor'))
+        assert_equal("/c/a#%23anchor",
+          W.new.url_for(only_path: true, controller: "c", action: "a", anchor: Struct.new(:to_param).new("#anchor"))
         )
       end
 
       def test_anchor_should_not_escape_safe_pchar
-        assert_equal('/c/a#name=user&email=user@domain.com',
-          W.new.url_for(:only_path => true, :controller => 'c', :action => 'a', :anchor => Struct.new(:to_param).new('name=user&email=user@domain.com'))
+        assert_equal("/c/a#name=user&email=user@domain.com",
+          W.new.url_for(only_path: true, controller: "c", action: "a", anchor: Struct.new(:to_param).new("name=user&email=user@domain.com"))
         )
       end
 
       def test_default_host
         add_host!
-        assert_equal('http://www.basecamphq.com/c/a/i',
-          W.new.url_for(:controller => 'c', :action => 'a', :id => 'i')
+        assert_equal("http://www.basecamphq.com/c/a/i",
+          W.new.url_for(controller: "c", action: "a", id: "i")
         )
       end
 
       def test_host_may_be_overridden
         add_host!
-        assert_equal('http://37signals.basecamphq.com/c/a/i',
-          W.new.url_for(:host => '37signals.basecamphq.com', :controller => 'c', :action => 'a', :id => 'i')
+        assert_equal("http://37signals.basecamphq.com/c/a/i",
+          W.new.url_for(host: "37signals.basecamphq.com", controller: "c", action: "a", id: "i")
         )
       end
 
       def test_subdomain_may_be_changed
         add_host!
-        assert_equal('http://api.basecamphq.com/c/a/i',
-          W.new.url_for(:subdomain => 'api', :controller => 'c', :action => 'a', :id => 'i')
+        assert_equal("http://api.basecamphq.com/c/a/i",
+          W.new.url_for(subdomain: "api", controller: "c", action: "a", id: "i")
         )
       end
 
       def test_subdomain_may_be_object
-        model = Class.new { def self.to_param; 'api'; end }
+        model = Class.new { def self.to_param; "api"; end }
         add_host!
-        assert_equal('http://api.basecamphq.com/c/a/i',
-          W.new.url_for(:subdomain => model, :controller => 'c', :action => 'a', :id => 'i')
+        assert_equal("http://api.basecamphq.com/c/a/i",
+          W.new.url_for(subdomain: model, controller: "c", action: "a", id: "i")
         )
       end
 
       def test_subdomain_may_be_removed
         add_host!
-        assert_equal('http://basecamphq.com/c/a/i',
-          W.new.url_for(:subdomain => false, :controller => 'c', :action => 'a', :id => 'i')
+        assert_equal("http://basecamphq.com/c/a/i",
+          W.new.url_for(subdomain: false, controller: "c", action: "a", id: "i")
         )
       end
 
       def test_subdomain_may_be_removed_with_blank_string
-        W.default_url_options[:host] = 'api.basecamphq.com'
-        assert_equal('http://basecamphq.com/c/a/i',
-          W.new.url_for(:subdomain => '', :controller => 'c', :action => 'a', :id => 'i')
+        W.default_url_options[:host] = "api.basecamphq.com"
+        assert_equal("http://basecamphq.com/c/a/i",
+          W.new.url_for(subdomain: "", controller: "c", action: "a", id: "i")
         )
       end
 
       def test_multiple_subdomains_may_be_removed
-        W.default_url_options[:host] = 'mobile.www.api.basecamphq.com'
-        assert_equal('http://basecamphq.com/c/a/i',
-          W.new.url_for(:subdomain => false, :controller => 'c', :action => 'a', :id => 'i')
+        W.default_url_options[:host] = "mobile.www.api.basecamphq.com"
+        assert_equal("http://basecamphq.com/c/a/i",
+          W.new.url_for(subdomain: false, controller: "c", action: "a", id: "i")
         )
       end
 
       def test_subdomain_may_be_accepted_with_numeric_host
         add_numeric_host!
-        assert_equal('http://127.0.0.1/c/a/i',
-          W.new.url_for(:subdomain => 'api', :controller => 'c', :action => 'a', :id => 'i')
+        assert_equal("http://127.0.0.1/c/a/i",
+          W.new.url_for(subdomain: "api", controller: "c", action: "a", id: "i")
         )
       end
 
       def test_domain_may_be_changed
         add_host!
-        assert_equal('http://www.37signals.com/c/a/i',
-          W.new.url_for(:domain => '37signals.com', :controller => 'c', :action => 'a', :id => 'i')
+        assert_equal("http://www.37signals.com/c/a/i",
+          W.new.url_for(domain: "37signals.com", controller: "c", action: "a", id: "i")
         )
       end
 
       def test_tld_length_may_be_changed
         add_host!
-        assert_equal('http://mobile.www.basecamphq.com/c/a/i',
-          W.new.url_for(:subdomain => 'mobile', :tld_length => 2, :controller => 'c', :action => 'a', :id => 'i')
+        assert_equal("http://mobile.www.basecamphq.com/c/a/i",
+          W.new.url_for(subdomain: "mobile", tld_length: 2, controller: "c", action: "a", id: "i")
         )
       end
 
       def test_port
         add_host!
-        assert_equal('http://www.basecamphq.com:3000/c/a/i',
-          W.new.url_for(:controller => 'c', :action => 'a', :id => 'i', :port => 3000)
+        assert_equal("http://www.basecamphq.com:3000/c/a/i",
+          W.new.url_for(controller: "c", action: "a", id: "i", port: 3000)
         )
       end
 
       def test_default_port
         add_host!
         add_port!
-        assert_equal('http://www.basecamphq.com:3000/c/a/i',
-          W.new.url_for(:controller => 'c', :action => 'a', :id => 'i')
+        assert_equal("http://www.basecamphq.com:3000/c/a/i",
+          W.new.url_for(controller: "c", action: "a", id: "i")
         )
       end
 
       def test_protocol
         add_host!
-        assert_equal('https://www.basecamphq.com/c/a/i',
-          W.new.url_for(:controller => 'c', :action => 'a', :id => 'i', :protocol => 'https')
+        assert_equal("https://www.basecamphq.com/c/a/i",
+          W.new.url_for(controller: "c", action: "a", id: "i", protocol: "https")
         )
       end
 
       def test_protocol_with_and_without_separators
         add_host!
-        assert_equal('https://www.basecamphq.com/c/a/i',
-          W.new.url_for(:controller => 'c', :action => 'a', :id => 'i', :protocol => 'https')
+        assert_equal("https://www.basecamphq.com/c/a/i",
+          W.new.url_for(controller: "c", action: "a", id: "i", protocol: "https")
         )
-        assert_equal('https://www.basecamphq.com/c/a/i',
-          W.new.url_for(:controller => 'c', :action => 'a', :id => 'i', :protocol => 'https:')
+        assert_equal("https://www.basecamphq.com/c/a/i",
+          W.new.url_for(controller: "c", action: "a", id: "i", protocol: "https:")
         )
-        assert_equal('https://www.basecamphq.com/c/a/i',
-          W.new.url_for(:controller => 'c', :action => 'a', :id => 'i', :protocol => 'https://')
+        assert_equal("https://www.basecamphq.com/c/a/i",
+          W.new.url_for(controller: "c", action: "a", id: "i", protocol: "https://")
         )
       end
 
       def test_without_protocol
         add_host!
-        assert_equal('//www.basecamphq.com/c/a/i',
-          W.new.url_for(:controller => 'c', :action => 'a', :id => 'i', :protocol => '//')
+        assert_equal("//www.basecamphq.com/c/a/i",
+          W.new.url_for(controller: "c", action: "a", id: "i", protocol: "//")
         )
-        assert_equal('//www.basecamphq.com/c/a/i',
-          W.new.url_for(:controller => 'c', :action => 'a', :id => 'i', :protocol => false)
+        assert_equal("//www.basecamphq.com/c/a/i",
+          W.new.url_for(controller: "c", action: "a", id: "i", protocol: false)
         )
       end
 
@@ -212,74 +214,74 @@ module AbstractController
         add_host!
         add_port!
 
-        assert_equal('//www.basecamphq.com:3000/c/a/i',
-          W.new.url_for(:controller => 'c', :action => 'a', :id => 'i', :protocol => '//')
+        assert_equal("//www.basecamphq.com:3000/c/a/i",
+          W.new.url_for(controller: "c", action: "a", id: "i", protocol: "//")
         )
-        assert_equal('//www.basecamphq.com:3000/c/a/i',
-          W.new.url_for(:controller => 'c', :action => 'a', :id => 'i', :protocol => false)
+        assert_equal("//www.basecamphq.com:3000/c/a/i",
+          W.new.url_for(controller: "c", action: "a", id: "i", protocol: false)
         )
       end
 
       def test_trailing_slash
         add_host!
-        options = {:controller => 'foo', :trailing_slash => true, :action => 'bar', :id => '33'}
-        assert_equal('http://www.basecamphq.com/foo/bar/33/', W.new.url_for(options) )
+        options = { controller: "foo", trailing_slash: true, action: "bar", id: "33" }
+        assert_equal("http://www.basecamphq.com/foo/bar/33/", W.new.url_for(options))
       end
 
       def test_trailing_slash_with_protocol
         add_host!
-        options = { :trailing_slash => true,:protocol => 'https', :controller => 'foo', :action => 'bar', :id => '33'}
-        assert_equal('https://www.basecamphq.com/foo/bar/33/', W.new.url_for(options) )
-        assert_equal 'https://www.basecamphq.com/foo/bar/33/?query=string', W.new.url_for(options.merge({:query => 'string'}))
+        options = { trailing_slash: true, protocol: "https", controller: "foo", action: "bar", id: "33" }
+        assert_equal("https://www.basecamphq.com/foo/bar/33/", W.new.url_for(options))
+        assert_equal "https://www.basecamphq.com/foo/bar/33/?query=string", W.new.url_for(options.merge(query: "string"))
       end
 
       def test_trailing_slash_with_only_path
-        options = {:controller => 'foo', :trailing_slash => true}
-        assert_equal '/foo/', W.new.url_for(options.merge({:only_path => true}))
-        options.update({:action => 'bar', :id => '33'})
-        assert_equal '/foo/bar/33/', W.new.url_for(options.merge({:only_path => true}))
-        assert_equal '/foo/bar/33/?query=string', W.new.url_for(options.merge({:query => 'string',:only_path => true}))
+        options = { controller: "foo", trailing_slash: true }
+        assert_equal "/foo/", W.new.url_for(options.merge(only_path: true))
+        options.update(action: "bar", id: "33")
+        assert_equal "/foo/bar/33/", W.new.url_for(options.merge(only_path: true))
+        assert_equal "/foo/bar/33/?query=string", W.new.url_for(options.merge(query: "string", only_path: true))
       end
 
       def test_trailing_slash_with_anchor
-        options = {:trailing_slash => true, :controller => 'foo', :action => 'bar', :id => '33', :only_path => true, :anchor=> 'chapter7'}
-        assert_equal '/foo/bar/33/#chapter7', W.new.url_for(options)
-        assert_equal '/foo/bar/33/?query=string#chapter7', W.new.url_for(options.merge({:query => 'string'}))
+        options = { trailing_slash: true, controller: "foo", action: "bar", id: "33", only_path: true, anchor: "chapter7" }
+        assert_equal "/foo/bar/33/#chapter7", W.new.url_for(options)
+        assert_equal "/foo/bar/33/?query=string#chapter7", W.new.url_for(options.merge(query: "string"))
       end
 
       def test_trailing_slash_with_params
-        url = W.new.url_for(:trailing_slash => true, :only_path => true, :controller => 'cont', :action => 'act', :p1 => 'cafe', :p2 => 'link')
+        url = W.new.url_for(trailing_slash: true, only_path: true, controller: "cont", action: "act", p1: "cafe", p2: "link")
         params = extract_params(url)
-        assert_equal({p1: 'cafe'}.to_query, params[0])
-        assert_equal({p2: 'link'}.to_query, params[1])
+        assert_equal({ p1: "cafe" }.to_query, params[0])
+        assert_equal({ p2: "link" }.to_query, params[1])
       end
 
       def test_relative_url_root_is_respected
         add_host!
-        assert_equal('https://www.basecamphq.com/subdir/c/a/i',
-          W.new.url_for(:controller => 'c', :action => 'a', :id => 'i', :protocol => 'https', :script_name => '/subdir')
+        assert_equal("https://www.basecamphq.com/subdir/c/a/i",
+          W.new.url_for(controller: "c", action: "a", id: "i", protocol: "https", script_name: "/subdir")
         )
       end
 
       def test_relative_url_root_is_respected_with_environment_variable
         # `config.relative_url_root` is set by ENV['RAILS_RELATIVE_URL_ROOT']
         w = Class.new {
-          config = ActionDispatch::Routing::RouteSet::Config.new '/subdir'
+          config = ActionDispatch::Routing::RouteSet::Config.new "/subdir"
           r = ActionDispatch::Routing::RouteSet.new(config)
-          r.draw { ActiveSupport::Deprecation.silence { get ':controller(/:action(/:id(.:format)))' } }
+          r.draw { ActiveSupport::Deprecation.silence { get ":controller(/:action(/:id(.:format)))" } }
           include r.url_helpers
         }
         add_host!(w)
-        assert_equal('https://www.basecamphq.com/subdir/c/a/i',
-          w.new.url_for(:controller => 'c', :action => 'a', :id => 'i', :protocol => 'https')
+        assert_equal("https://www.basecamphq.com/subdir/c/a/i",
+          w.new.url_for(controller: "c", action: "a", id: "i", protocol: "https")
         )
       end
 
       def test_named_routes
         with_routing do |set|
           set.draw do
-            get 'this/is/verbose', :to => 'home#index', :as => :no_args
-            get 'home/sweet/home/:user', :to => 'home#index', :as => :home
+            get "this/is/verbose", to: "home#index", as: :no_args
+            get "home/sweet/home/:user", to: "home#index", as: :home
           end
 
           # We need to create a new class in order to install the new named route.
@@ -287,43 +289,43 @@ module AbstractController
 
           controller = kls.new
           assert controller.respond_to?(:home_url)
-          assert_equal 'http://www.basecamphq.com/home/sweet/home/again',
-            controller.send(:home_url, :host => 'www.basecamphq.com', :user => 'again')
+          assert_equal "http://www.basecamphq.com/home/sweet/home/again",
+            controller.send(:home_url, host: "www.basecamphq.com", user: "again")
 
-          assert_equal("/home/sweet/home/alabama", controller.send(:home_path, :user => 'alabama', :host => 'unused'))
-          assert_equal("http://www.basecamphq.com/home/sweet/home/alabama", controller.send(:home_url, :user => 'alabama', :host => 'www.basecamphq.com'))
-          assert_equal("http://www.basecamphq.com/this/is/verbose", controller.send(:no_args_url, :host=>'www.basecamphq.com'))
+          assert_equal("/home/sweet/home/alabama", controller.send(:home_path, user: "alabama", host: "unused"))
+          assert_equal("http://www.basecamphq.com/home/sweet/home/alabama", controller.send(:home_url, user: "alabama", host: "www.basecamphq.com"))
+          assert_equal("http://www.basecamphq.com/this/is/verbose", controller.send(:no_args_url, host: "www.basecamphq.com"))
         end
       end
 
       def test_relative_url_root_is_respected_for_named_routes
         with_routing do |set|
           set.draw do
-            get '/home/sweet/home/:user', :to => 'home#index', :as => :home
+            get "/home/sweet/home/:user", to: "home#index", as: :home
           end
 
           kls = Class.new { include set.url_helpers }
           controller = kls.new
 
-          assert_equal 'http://www.basecamphq.com/subdir/home/sweet/home/again',
-            controller.send(:home_url, :host => 'www.basecamphq.com', :user => 'again', :script_name => "/subdir")
+          assert_equal "http://www.basecamphq.com/subdir/home/sweet/home/again",
+            controller.send(:home_url, host: "www.basecamphq.com", user: "again", script_name: "/subdir")
         end
       end
 
       def test_using_nil_script_name_properly_concats_with_original_script_name
         add_host!
-        assert_equal('https://www.basecamphq.com/subdir/c/a/i',
-          W.new.url_for(:controller => 'c', :action => 'a', :id => 'i', :protocol => 'https', :script_name => nil, :original_script_name => '/subdir')
+        assert_equal("https://www.basecamphq.com/subdir/c/a/i",
+          W.new.url_for(controller: "c", action: "a", id: "i", protocol: "https", script_name: nil, original_script_name: "/subdir")
         )
       end
 
       def test_only_path
         with_routing do |set|
           set.draw do
-            get 'home/sweet/home/:user', :to => 'home#index', :as => :home
+            get "home/sweet/home/:user", to: "home#index", as: :home
 
             ActiveSupport::Deprecation.silence do
-              get ':controller/:action/:id'
+              get ":controller/:action/:id"
             end
           end
 
@@ -331,83 +333,83 @@ module AbstractController
           kls = Class.new { include set.url_helpers }
           controller = kls.new
           assert_respond_to controller, :home_url
-          assert_equal '/brave/new/world',
-            controller.url_for(:controller => 'brave', :action => 'new', :id => 'world', :only_path => true)
+          assert_equal "/brave/new/world",
+            controller.url_for(controller: "brave", action: "new", id: "world", only_path: true)
 
-          assert_equal("/home/sweet/home/alabama", controller.home_path(:user => 'alabama', :host => 'unused'))
-          assert_equal("/home/sweet/home/alabama", controller.home_path('alabama'))
+          assert_equal("/home/sweet/home/alabama", controller.home_path(user: "alabama", host: "unused"))
+          assert_equal("/home/sweet/home/alabama", controller.home_path("alabama"))
         end
       end
 
       def test_one_parameter
-        assert_equal('/c/a?param=val',
-          W.new.url_for(:only_path => true, :controller => 'c', :action => 'a', :param => 'val')
+        assert_equal("/c/a?param=val",
+          W.new.url_for(only_path: true, controller: "c", action: "a", param: "val")
         )
       end
 
       def test_two_parameters
-        url = W.new.url_for(:only_path => true, :controller => 'c', :action => 'a', :p1 => 'X1', :p2 => 'Y2')
+        url = W.new.url_for(only_path: true, controller: "c", action: "a", p1: "X1", p2: "Y2")
         params = extract_params(url)
-        assert_equal({p1: 'X1'}.to_query, params[0])
-        assert_equal({p2: 'Y2'}.to_query, params[1])
+        assert_equal({ p1: "X1" }.to_query, params[0])
+        assert_equal({ p2: "Y2" }.to_query, params[1])
       end
 
       def test_hash_parameter
-        url = W.new.url_for(:only_path => true, :controller => 'c', :action => 'a', :query => {:name => 'Bob', :category => 'prof'})
+        url = W.new.url_for(only_path: true, controller: "c", action: "a", query: { name: "Bob", category: "prof" })
         params = extract_params(url)
-        assert_equal({'query[category]' => 'prof'}.to_query, params[0])
-        assert_equal({'query[name]' => 'Bob'}.to_query, params[1])
+        assert_equal({ "query[category]" => "prof" }.to_query, params[0])
+        assert_equal({ "query[name]" => "Bob" }.to_query, params[1])
       end
 
       def test_array_parameter
-        url = W.new.url_for(:only_path => true, :controller => 'c', :action => 'a', :query => ['Bob', 'prof'])
+        url = W.new.url_for(only_path: true, controller: "c", action: "a", query: ["Bob", "prof"])
         params = extract_params(url)
-        assert_equal({'query[]' => 'Bob'}.to_query, params[0])
-        assert_equal({'query[]' => 'prof'}.to_query, params[1])
+        assert_equal({ "query[]" => "Bob" }.to_query, params[0])
+        assert_equal({ "query[]" => "prof" }.to_query, params[1])
       end
 
       def test_hash_recursive_parameters
-        url = W.new.url_for(:only_path => true, :controller => 'c', :action => 'a', :query => {:person => {:name => 'Bob', :position => 'prof'}, :hobby => 'piercing'})
+        url = W.new.url_for(only_path: true, controller: "c", action: "a", query: { person: { name: "Bob", position: "prof" }, hobby: "piercing" })
         params = extract_params(url)
-        assert_equal({'query[hobby]'            => 'piercing'}.to_query, params[0])
-        assert_equal({'query[person][name]'     => 'Bob'     }.to_query, params[1])
-        assert_equal({'query[person][position]' => 'prof'    }.to_query, params[2])
+        assert_equal({ "query[hobby]"            => "piercing" }.to_query, params[0])
+        assert_equal({ "query[person][name]"     => "Bob"     }.to_query, params[1])
+        assert_equal({ "query[person][position]" => "prof"    }.to_query, params[2])
       end
 
       def test_hash_recursive_and_array_parameters
-        url = W.new.url_for(:only_path => true, :controller => 'c', :action => 'a', :id => 101, :query => {:person => {:name => 'Bob', :position => ['prof', 'art director']}, :hobby => 'piercing'})
+        url = W.new.url_for(only_path: true, controller: "c", action: "a", id: 101, query: { person: { name: "Bob", position: ["prof", "art director"] }, hobby: "piercing" })
         assert_match(%r(^/c/a/101), url)
         params = extract_params(url)
-        assert_equal({'query[hobby]'              => 'piercing'    }.to_query, params[0])
-        assert_equal({'query[person][name]'       => 'Bob'         }.to_query, params[1])
-        assert_equal({'query[person][position][]' => 'art director'}.to_query, params[2])
-        assert_equal({'query[person][position][]' => 'prof'        }.to_query, params[3])
+        assert_equal({ "query[hobby]"              => "piercing"    }.to_query, params[0])
+        assert_equal({ "query[person][name]"       => "Bob"         }.to_query, params[1])
+        assert_equal({ "query[person][position][]" => "art director" }.to_query, params[2])
+        assert_equal({ "query[person][position][]" => "prof"        }.to_query, params[3])
       end
 
       def test_url_action_controller_parameters
         add_host!
-        assert_raise(ArgumentError) do
-          W.new.url_for(ActionController::Parameters.new(:controller => 'c', :action => 'a', protocol: 'javascript', f: '%0Aeval(name)'))
+        assert_raise(ActionController::UnfilteredParameters) do
+          W.new.url_for(ActionController::Parameters.new(controller: "c", action: "a", protocol: "javascript", f: "%0Aeval(name)"))
         end
       end
 
       def test_path_generation_for_symbol_parameter_keys
-        assert_generates("/image", :controller=> :image)
+        assert_generates("/image", controller: :image)
       end
 
       def test_named_routes_with_nil_keys
         with_routing do |set|
           set.draw do
-            get 'posts.:format', :to => 'posts#index', :as => :posts
-            get '/', :to => 'posts#index', :as => :main
+            get "posts.:format", to: "posts#index", as: :posts
+            get "/", to: "posts#index", as: :main
           end
 
           # We need to create a new class in order to install the new named route.
           kls = Class.new { include set.url_helpers }
-          kls.default_url_options[:host] = 'www.basecamphq.com'
+          kls.default_url_options[:host] = "www.basecamphq.com"
 
           controller = kls.new
-          params = {:action => :index, :controller => :posts, :format => :xml}
+          params = { action: :index, controller: :posts, format: :xml }
           assert_equal("http://www.basecamphq.com/posts.xml", controller.send(:url_for, params))
           params[:format] = nil
           assert_equal("http://www.basecamphq.com/", controller.send(:url_for, params))
@@ -418,35 +420,35 @@ module AbstractController
         first_class = Class.new { include ActionController::UrlFor }
         second_class = Class.new { include ActionController::UrlFor }
 
-        first_host, second_host = 'firsthost.com', 'secondhost.com'
+        first_host, second_host = "firsthost.com", "secondhost.com"
 
         first_class.default_url_options[:host] = first_host
         second_class.default_url_options[:host] = second_host
 
-        assert_equal  first_host, first_class.default_url_options[:host]
+        assert_equal first_host, first_class.default_url_options[:host]
         assert_equal second_host, second_class.default_url_options[:host]
       end
 
       def test_with_stringified_keys
-        assert_equal("/c", W.new.url_for('controller' => 'c', 'only_path' => true))
-        assert_equal("/c/a", W.new.url_for('controller' => 'c', 'action' => 'a', 'only_path' => true))
+        assert_equal("/c", W.new.url_for("controller" => "c", "only_path" => true))
+        assert_equal("/c/a", W.new.url_for("controller" => "c", "action" => "a", "only_path" => true))
       end
 
       def test_with_hash_with_indifferent_access
-        W.default_url_options[:controller] = 'd'
+        W.default_url_options[:controller] = "d"
         W.default_url_options[:only_path]  = false
-        assert_equal("/c", W.new.url_for(ActiveSupport::HashWithIndifferentAccess.new('controller' => 'c', 'only_path' => true)))
+        assert_equal("/c", W.new.url_for(ActiveSupport::HashWithIndifferentAccess.new("controller" => "c", "only_path" => true)))
 
-        W.default_url_options[:action] = 'b'
-        assert_equal("/c/a", W.new.url_for(ActiveSupport::HashWithIndifferentAccess.new('controller' => 'c', 'action' => 'a', 'only_path' => true)))
+        W.default_url_options[:action] = "b"
+        assert_equal("/c/a", W.new.url_for(ActiveSupport::HashWithIndifferentAccess.new("controller" => "c", "action" => "a", "only_path" => true)))
       end
 
       def test_url_params_with_nil_to_param_are_not_in_url
-        assert_equal("/c/a", W.new.url_for(:only_path => true, :controller => 'c', :action => 'a', :id => Struct.new(:to_param).new(nil)))
+        assert_equal("/c/a", W.new.url_for(only_path: true, controller: "c", action: "a", id: Struct.new(:to_param).new(nil)))
       end
 
       def test_false_url_params_are_included_in_query
-        assert_equal("/c/a?show=false", W.new.url_for(:only_path => true, :controller => 'c', :action => 'a', :show => false))
+        assert_equal("/c/a?show=false", W.new.url_for(only_path: true, controller: "c", action: "a", show: false))
       end
 
       def test_url_generation_with_array_and_hash
@@ -458,11 +460,11 @@ module AbstractController
           end
 
           kls = Class.new { include set.url_helpers }
-          kls.default_url_options[:host] = 'www.basecamphq.com'
+          kls.default_url_options[:host] = "www.basecamphq.com"
 
           controller = kls.new
           assert_equal("http://www.basecamphq.com/admin/posts/new?param=value",
-            controller.send(:url_for, [:new, :admin, :post, { param: 'value' }])
+            controller.send(:url_for, [:new, :admin, :post, { param: "value" }])
           )
         end
       end
@@ -476,9 +478,9 @@ module AbstractController
           end
 
           kls = Class.new { include set.url_helpers }
-          kls.default_url_options[:host] = 'www.basecamphq.com'
+          kls.default_url_options[:host] = "www.basecamphq.com"
 
-          original_components = [:new, :admin, :post, { param: 'value' }]
+          original_components = [:new, :admin, :post, { param: "value" }]
           components = original_components.dup
 
           kls.new.url_for(components)
@@ -487,9 +489,30 @@ module AbstractController
         end
       end
 
+      def test_default_params_first_empty
+        with_routing do |set|
+          set.draw do
+            get "(:param1)/test(/:param2)" => "index#index",
+              defaults: {
+                param1: 1,
+                param2: 2
+              },
+              constraints: {
+                param1: /\d*/,
+                param2: /\d+/
+              }
+          end
+
+          kls = Class.new { include set.url_helpers }
+          kls.default_url_options[:host] = "www.basecamphq.com"
+
+          assert_equal "http://www.basecamphq.com/test", kls.new.url_for(controller: "index", param1: "1")
+        end
+      end
+
       private
         def extract_params(url)
-          url.split('?', 2).last.split('&').sort
+          url.split("?", 2).last.split("&").sort
         end
     end
   end
diff --git a/actionpack/test/controller/url_rewriter_test.rb b/actionpack/test/controller/url_rewriter_test.rb
index bc0d215530..ca83b850d5 100644
--- a/actionpack/test/controller/url_rewriter_test.rb
+++ b/actionpack/test/controller/url_rewriter_test.rb
@@ -1,12 +1,14 @@
-require 'abstract_unit'
-require 'controller/fake_controllers'
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "controller/fake_controllers"
 
 class UrlRewriterTests < ActionController::TestCase
   class Rewriter
     def initialize(request)
       @options = {
-        :host => request.host_with_port,
-        :protocol => request.protocol
+        host: request.host_with_port,
+        protocol: request.protocol
       }
     end
 
@@ -17,75 +19,74 @@ class UrlRewriterTests < ActionController::TestCase
 
   def setup
     @params = {}
-    @rewriter = Rewriter.new(@request) #.new(@request, @params)
+    @rewriter = Rewriter.new(@request)
     @routes = ActionDispatch::Routing::RouteSet.new.tap do |r|
       r.draw do
         ActiveSupport::Deprecation.silence do
-          get ':controller(/:action(/:id))'
+          get ":controller(/:action(/:id))"
         end
       end
     end
   end
 
   def test_port
-    assert_equal('http://test.host:1271/c/a/i',
-      @rewriter.rewrite(@routes, :controller => 'c', :action => 'a', :id => 'i', :port => 1271)
+    assert_equal("http://test.host:1271/c/a/i",
+      @rewriter.rewrite(@routes, controller: "c", action: "a", id: "i", port: 1271)
     )
   end
 
   def test_protocol_with_and_without_separator
-    assert_equal('https://test.host/c/a/i',
-      @rewriter.rewrite(@routes, :protocol => 'https', :controller => 'c', :action => 'a', :id => 'i')
+    assert_equal("https://test.host/c/a/i",
+      @rewriter.rewrite(@routes, protocol: "https", controller: "c", action: "a", id: "i")
     )
 
-    assert_equal('https://test.host/c/a/i',
-      @rewriter.rewrite(@routes, :protocol => 'https://', :controller => 'c', :action => 'a', :id => 'i')
+    assert_equal("https://test.host/c/a/i",
+      @rewriter.rewrite(@routes, protocol: "https://", controller: "c", action: "a", id: "i")
     )
   end
 
   def test_user_name_and_password
     assert_equal(
-      'http://david:secret@test.host/c/a/i',
-      @rewriter.rewrite(@routes, :user => "david", :password => "secret", :controller => 'c', :action => 'a', :id => 'i')
+      "http://david:secret@test.host/c/a/i",
+      @rewriter.rewrite(@routes, user: "david", password: "secret", controller: "c", action: "a", id: "i")
     )
   end
 
   def test_user_name_and_password_with_escape_codes
     assert_equal(
-      'http://openid.aol.com%2Fnextangler:one+two%3F@test.host/c/a/i',
-      @rewriter.rewrite(@routes, :user => "openid.aol.com/nextangler", :password => "one two?", :controller => 'c', :action => 'a', :id => 'i')
+      "http://openid.aol.com%2Fnextangler:one+two%3F@test.host/c/a/i",
+      @rewriter.rewrite(@routes, user: "openid.aol.com/nextangler", password: "one two?", controller: "c", action: "a", id: "i")
     )
   end
 
   def test_anchor
     assert_equal(
-      'http://test.host/c/a/i#anchor',
-      @rewriter.rewrite(@routes, :controller => 'c', :action => 'a', :id => 'i', :anchor => 'anchor')
+      "http://test.host/c/a/i#anchor",
+      @rewriter.rewrite(@routes, controller: "c", action: "a", id: "i", anchor: "anchor")
     )
   end
 
   def test_anchor_should_call_to_param
     assert_equal(
-      'http://test.host/c/a/i#anchor',
-      @rewriter.rewrite(@routes, :controller => 'c', :action => 'a', :id => 'i', :anchor => Struct.new(:to_param).new('anchor'))
+      "http://test.host/c/a/i#anchor",
+      @rewriter.rewrite(@routes, controller: "c", action: "a", id: "i", anchor: Struct.new(:to_param).new("anchor"))
     )
   end
 
   def test_anchor_should_be_uri_escaped
     assert_equal(
-      'http://test.host/c/a/i#anc/hor',
-      @rewriter.rewrite(@routes, :controller => 'c', :action => 'a', :id => 'i', :anchor => Struct.new(:to_param).new('anc/hor'))
+      "http://test.host/c/a/i#anc/hor",
+      @rewriter.rewrite(@routes, controller: "c", action: "a", id: "i", anchor: Struct.new(:to_param).new("anc/hor"))
     )
   end
 
   def test_trailing_slash
-    options = {:controller => 'foo', :action => 'bar', :id => '3', :only_path => true}
-    assert_equal '/foo/bar/3', @rewriter.rewrite(@routes, options)
-    assert_equal '/foo/bar/3?query=string', @rewriter.rewrite(@routes, options.merge({:query => 'string'}))
-    options.update({:trailing_slash => true})
-    assert_equal '/foo/bar/3/', @rewriter.rewrite(@routes, options)
-    options.update({:query => 'string'})
-    assert_equal '/foo/bar/3/?query=string', @rewriter.rewrite(@routes, options)
+    options = { controller: "foo", action: "bar", id: "3", only_path: true }
+    assert_equal "/foo/bar/3", @rewriter.rewrite(@routes, options)
+    assert_equal "/foo/bar/3?query=string", @rewriter.rewrite(@routes, options.merge(query: "string"))
+    options.update(trailing_slash: true)
+    assert_equal "/foo/bar/3/", @rewriter.rewrite(@routes, options)
+    options.update(query: "string")
+    assert_equal "/foo/bar/3/?query=string", @rewriter.rewrite(@routes, options)
   end
 end
-
diff --git a/actionpack/test/controller/webservice_test.rb b/actionpack/test/controller/webservice_test.rb
index daf17558aa..4a10637b54 100644
--- a/actionpack/test/controller/webservice_test.rb
+++ b/actionpack/test/controller/webservice_test.rb
@@ -1,5 +1,7 @@
-require 'abstract_unit'
-require 'active_support/json/decoding'
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "active_support/json/decoding"
 
 class WebServiceTest < ActionDispatch::IntegrationTest
   class TestController < ActionController::Base
@@ -7,7 +9,7 @@ class WebServiceTest < ActionDispatch::IntegrationTest
       if params[:full]
         render plain: dump_params_keys
       else
-        render plain: (params.keys - ['controller', 'action']).sort.join(", ")
+        render plain: (params.keys - ["controller", "action"]).sort.join(", ")
       end
     end
 
@@ -21,8 +23,8 @@ class WebServiceTest < ActionDispatch::IntegrationTest
           value = ""
         end
 
-        s << ", " unless s.empty?
-        s << "#{k}#{value}"
+        s += ", " unless s.empty?
+        s += "#{k}#{value}"
       end
     end
   end
@@ -35,7 +37,7 @@ class WebServiceTest < ActionDispatch::IntegrationTest
   def test_check_parameters
     with_test_route_set do
       get "/"
-      assert_equal '', @controller.response.body
+      assert_equal "", @controller.response.body
     end
   end
 
@@ -43,11 +45,11 @@ class WebServiceTest < ActionDispatch::IntegrationTest
     with_test_route_set do
       post "/",
         params: '{"entry":{"summary":"content..."}}',
-        headers: { 'CONTENT_TYPE' => 'application/json' }
+        headers: { "CONTENT_TYPE" => "application/json" }
 
-      assert_equal 'entry', @controller.response.body
+      assert_equal "entry", @controller.response.body
       assert @controller.params.has_key?(:entry)
-      assert_equal 'content...', @controller.params["entry"]['summary']
+      assert_equal "content...", @controller.params["entry"]["summary"]
     end
   end
 
@@ -55,34 +57,34 @@ class WebServiceTest < ActionDispatch::IntegrationTest
     with_test_route_set do
       put "/",
         params: '{"entry":{"summary":"content..."}}',
-        headers: { 'CONTENT_TYPE' => 'application/json' }
+        headers: { "CONTENT_TYPE" => "application/json" }
 
-      assert_equal 'entry', @controller.response.body
+      assert_equal "entry", @controller.response.body
       assert @controller.params.has_key?(:entry)
-      assert_equal 'content...', @controller.params["entry"]['summary']
+      assert_equal "content...", @controller.params["entry"]["summary"]
     end
   end
 
   def test_register_and_use_json_simple
     with_test_route_set do
-      with_params_parsers Mime[:json] => Proc.new { |data| ActiveSupport::JSON.decode(data)['request'].with_indifferent_access } do
+      with_params_parsers Mime[:json] => Proc.new { |data| ActiveSupport::JSON.decode(data)["request"].with_indifferent_access } do
         post "/",
           params: '{"request":{"summary":"content...","title":"JSON"}}',
-          headers: { 'CONTENT_TYPE' => 'application/json' }
+          headers: { "CONTENT_TYPE" => "application/json" }
 
-        assert_equal 'summary, title', @controller.response.body
+        assert_equal "summary, title", @controller.response.body
         assert @controller.params.has_key?(:summary)
         assert @controller.params.has_key?(:title)
-        assert_equal 'content...', @controller.params["summary"]
-        assert_equal 'JSON', @controller.params["title"]
+        assert_equal "content...", @controller.params["summary"]
+        assert_equal "JSON", @controller.params["title"]
       end
     end
   end
 
   def test_use_json_with_empty_request
     with_test_route_set do
-      assert_nothing_raised { post "/", headers: { 'CONTENT_TYPE' => 'application/json' } }
-      assert_equal '', @controller.response.body
+      assert_nothing_raised { post "/", headers: { "CONTENT_TYPE" => "application/json" } }
+      assert_equal "", @controller.response.body
     end
   end
 
@@ -90,9 +92,9 @@ class WebServiceTest < ActionDispatch::IntegrationTest
     with_test_route_set do
       post "/?full=1",
         params: '{"first-key":{"sub-key":"..."}}',
-        headers: { 'CONTENT_TYPE' => 'application/json' }
-      assert_equal 'action, controller, first-key(sub-key), full', @controller.response.body
-      assert_equal "...", @controller.params['first-key']['sub-key']
+        headers: { "CONTENT_TYPE" => "application/json" }
+      assert_equal "action, controller, first-key(sub-key), full", @controller.response.body
+      assert_equal "...", @controller.params["first-key"]["sub-key"]
     end
   end
 
@@ -102,8 +104,8 @@ class WebServiceTest < ActionDispatch::IntegrationTest
         { json: Proc.new { |data| raise Interrupt } }
       end
 
-      def content_length; get_header('rack.input').length; end
-    end.new({ 'rack.input' => StringIO.new('{"title":"JSON"}}'), 'CONTENT_TYPE' => 'application/json' })
+      def content_length; get_header("rack.input").length; end
+    end.new("rack.input" => StringIO.new('{"title":"JSON"}}'), "CONTENT_TYPE" => "application/json")
 
     assert_raises(Interrupt) do
       req.request_parameters
@@ -125,7 +127,7 @@ class WebServiceTest < ActionDispatch::IntegrationTest
     def with_test_route_set
       with_routing do |set|
         set.draw do
-          match '/', :to => 'web_service_test/test#assign_parameters', :via => :all
+          match "/", to: "web_service_test/test#assign_parameters", via: :all
         end
         yield
       end
diff --git a/actionpack/test/dispatch/callbacks_test.rb b/actionpack/test/dispatch/callbacks_test.rb
index 7b707df7f6..fc80191c02 100644
--- a/actionpack/test/dispatch/callbacks_test.rb
+++ b/actionpack/test/dispatch/callbacks_test.rb
@@ -1,4 +1,6 @@
-require 'abstract_unit'
+# frozen_string_literal: true
+
+require "abstract_unit"
 
 class DispatcherTest < ActiveSupport::TestCase
   class Foo
@@ -7,7 +9,7 @@ class DispatcherTest < ActiveSupport::TestCase
 
   class DummyApp
     def call(env)
-      [200, {}, 'response']
+      [200, {}, "response"]
     end
   end
 
@@ -35,30 +37,11 @@ class DispatcherTest < ActiveSupport::TestCase
     assert_equal 6, Foo.b
   end
 
-  def test_to_prepare_and_cleanup_delegation
-    prepared = cleaned = false
-    assert_deprecated do
-      ActionDispatch::Callbacks.to_prepare { prepared = true }
-      ActionDispatch::Callbacks.to_prepare { cleaned = true }
-    end
-
-    assert_deprecated do
-      ActionDispatch::Reloader.prepare!
-    end
-    assert prepared
-
-    assert_deprecated do
-      ActionDispatch::Reloader.cleanup!
-    end
-    assert cleaned
-  end
-
   private
 
     def dispatch(&block)
       ActionDispatch::Callbacks.new(block || DummyApp.new).call(
-        {'rack.input' => StringIO.new('')}
+        "rack.input" => StringIO.new("")
       )
     end
-
 end
diff --git a/actionpack/test/dispatch/content_security_policy_test.rb b/actionpack/test/dispatch/content_security_policy_test.rb
new file mode 100644
index 0000000000..7c4a65a633
--- /dev/null
+++ b/actionpack/test/dispatch/content_security_policy_test.rb
@@ -0,0 +1,368 @@
+# frozen_string_literal: true
+
+require "abstract_unit"
+
+class ContentSecurityPolicyTest < ActiveSupport::TestCase
+  def setup
+    @policy = ActionDispatch::ContentSecurityPolicy.new
+  end
+
+  def test_build
+    assert_equal ";", @policy.build
+
+    @policy.script_src :self
+    assert_equal "script-src 'self';", @policy.build
+  end
+
+  def test_dup
+    @policy.img_src :self
+    @policy.block_all_mixed_content
+    @policy.upgrade_insecure_requests
+    @policy.sandbox
+    copied = @policy.dup
+    assert_equal copied.build, @policy.build
+  end
+
+  def test_mappings
+    @policy.script_src :data
+    assert_equal "script-src data:;", @policy.build
+
+    @policy.script_src :mediastream
+    assert_equal "script-src mediastream:;", @policy.build
+
+    @policy.script_src :blob
+    assert_equal "script-src blob:;", @policy.build
+
+    @policy.script_src :filesystem
+    assert_equal "script-src filesystem:;", @policy.build
+
+    @policy.script_src :self
+    assert_equal "script-src 'self';", @policy.build
+
+    @policy.script_src :unsafe_inline
+    assert_equal "script-src 'unsafe-inline';", @policy.build
+
+    @policy.script_src :unsafe_eval
+    assert_equal "script-src 'unsafe-eval';", @policy.build
+
+    @policy.script_src :none
+    assert_equal "script-src 'none';", @policy.build
+
+    @policy.script_src :strict_dynamic
+    assert_equal "script-src 'strict-dynamic';", @policy.build
+
+    @policy.script_src :none, :report_sample
+    assert_equal "script-src 'none' 'report-sample';", @policy.build
+  end
+
+  def test_fetch_directives
+    @policy.child_src :self
+    assert_match %r{child-src 'self'}, @policy.build
+
+    @policy.child_src false
+    assert_no_match %r{child-src}, @policy.build
+
+    @policy.connect_src :self
+    assert_match %r{connect-src 'self'}, @policy.build
+
+    @policy.connect_src false
+    assert_no_match %r{connect-src}, @policy.build
+
+    @policy.default_src :self
+    assert_match %r{default-src 'self'}, @policy.build
+
+    @policy.default_src false
+    assert_no_match %r{default-src}, @policy.build
+
+    @policy.font_src :self
+    assert_match %r{font-src 'self'}, @policy.build
+
+    @policy.font_src false
+    assert_no_match %r{font-src}, @policy.build
+
+    @policy.frame_src :self
+    assert_match %r{frame-src 'self'}, @policy.build
+
+    @policy.frame_src false
+    assert_no_match %r{frame-src}, @policy.build
+
+    @policy.img_src :self
+    assert_match %r{img-src 'self'}, @policy.build
+
+    @policy.img_src false
+    assert_no_match %r{img-src}, @policy.build
+
+    @policy.manifest_src :self
+    assert_match %r{manifest-src 'self'}, @policy.build
+
+    @policy.manifest_src false
+    assert_no_match %r{manifest-src}, @policy.build
+
+    @policy.media_src :self
+    assert_match %r{media-src 'self'}, @policy.build
+
+    @policy.media_src false
+    assert_no_match %r{media-src}, @policy.build
+
+    @policy.object_src :self
+    assert_match %r{object-src 'self'}, @policy.build
+
+    @policy.object_src false
+    assert_no_match %r{object-src}, @policy.build
+
+    @policy.script_src :self
+    assert_match %r{script-src 'self'}, @policy.build
+
+    @policy.script_src false
+    assert_no_match %r{script-src}, @policy.build
+
+    @policy.style_src :self
+    assert_match %r{style-src 'self'}, @policy.build
+
+    @policy.style_src false
+    assert_no_match %r{style-src}, @policy.build
+
+    @policy.worker_src :self
+    assert_match %r{worker-src 'self'}, @policy.build
+
+    @policy.worker_src false
+    assert_no_match %r{worker-src}, @policy.build
+  end
+
+  def test_document_directives
+    @policy.base_uri "https://example.com"
+    assert_match %r{base-uri https://example\.com;}, @policy.build
+
+    @policy.plugin_types "application/x-shockwave-flash"
+    assert_match %r{plugin-types application/x-shockwave-flash;}, @policy.build
+
+    @policy.sandbox
+    assert_match %r{sandbox;}, @policy.build
+
+    @policy.sandbox "allow-scripts", "allow-modals"
+    assert_match %r{sandbox allow-scripts allow-modals;}, @policy.build
+
+    @policy.sandbox false
+    assert_no_match %r{sandbox}, @policy.build
+  end
+
+  def test_navigation_directives
+    @policy.form_action :self
+    assert_match %r{form-action 'self';}, @policy.build
+
+    @policy.frame_ancestors :self
+    assert_match %r{frame-ancestors 'self';}, @policy.build
+  end
+
+  def test_reporting_directives
+    @policy.report_uri "/violations"
+    assert_match %r{report-uri /violations;}, @policy.build
+  end
+
+  def test_other_directives
+    @policy.block_all_mixed_content
+    assert_match %r{block-all-mixed-content;}, @policy.build
+
+    @policy.block_all_mixed_content false
+    assert_no_match %r{block-all-mixed-content}, @policy.build
+
+    @policy.require_sri_for :script, :style
+    assert_match %r{require-sri-for script style;}, @policy.build
+
+    @policy.require_sri_for "script", "style"
+    assert_match %r{require-sri-for script style;}, @policy.build
+
+    @policy.require_sri_for
+    assert_no_match %r{require-sri-for}, @policy.build
+
+    @policy.upgrade_insecure_requests
+    assert_match %r{upgrade-insecure-requests;}, @policy.build
+
+    @policy.upgrade_insecure_requests false
+    assert_no_match %r{upgrade-insecure-requests}, @policy.build
+  end
+
+  def test_multiple_sources
+    @policy.script_src :self, :https
+    assert_equal "script-src 'self' https:;", @policy.build
+  end
+
+  def test_multiple_directives
+    @policy.script_src :self, :https
+    @policy.style_src :self, :https
+    assert_equal "script-src 'self' https:; style-src 'self' https:;", @policy.build
+  end
+
+  def test_dynamic_directives
+    request = Struct.new(:host).new("www.example.com")
+    controller = Struct.new(:request).new(request)
+
+    @policy.script_src -> { request.host }
+    assert_equal "script-src www.example.com;", @policy.build(controller)
+  end
+
+  def test_mixed_static_and_dynamic_directives
+    @policy.script_src :self, -> { "foo.com" }, "bar.com"
+    assert_equal "script-src 'self' foo.com bar.com;", @policy.build(Object.new)
+  end
+
+  def test_invalid_directive_source
+    exception = assert_raises(ArgumentError) do
+      @policy.script_src [:self]
+    end
+
+    assert_equal "Invalid content security policy source: [:self]", exception.message
+  end
+
+  def test_missing_context_for_dynamic_source
+    @policy.script_src -> { request.host }
+
+    exception = assert_raises(RuntimeError) do
+      @policy.build
+    end
+
+    assert_match %r{\AMissing context for the dynamic content security policy source:}, exception.message
+  end
+
+  def test_raises_runtime_error_when_unexpected_source
+    @policy.plugin_types [:flash]
+
+    exception = assert_raises(RuntimeError) do
+      @policy.build
+    end
+
+    assert_match %r{\AUnexpected content security policy source:}, exception.message
+  end
+end
+
+class ContentSecurityPolicyIntegrationTest < ActionDispatch::IntegrationTest
+  class PolicyController < ActionController::Base
+    content_security_policy only: :inline do |p|
+      p.default_src "https://example.com"
+    end
+
+    content_security_policy only: :conditional, if: :condition? do |p|
+      p.default_src "https://true.example.com"
+    end
+
+    content_security_policy only: :conditional, unless: :condition? do |p|
+      p.default_src "https://false.example.com"
+    end
+
+    content_security_policy only: :report_only do |p|
+      p.report_uri "/violations"
+    end
+
+    content_security_policy_report_only only: :report_only
+
+    def index
+      head :ok
+    end
+
+    def inline
+      head :ok
+    end
+
+    def conditional
+      head :ok
+    end
+
+    def report_only
+      head :ok
+    end
+
+    private
+      def condition?
+        params[:condition] == "true"
+      end
+  end
+
+  ROUTES = ActionDispatch::Routing::RouteSet.new
+  ROUTES.draw do
+    scope module: "content_security_policy_integration_test" do
+      get "/", to: "policy#index"
+      get "/inline", to: "policy#inline"
+      get "/conditional", to: "policy#conditional"
+      get "/report-only", to: "policy#report_only"
+    end
+  end
+
+  POLICY = ActionDispatch::ContentSecurityPolicy.new do |p|
+    p.default_src :self
+  end
+
+  class PolicyConfigMiddleware
+    def initialize(app)
+      @app = app
+    end
+
+    def call(env)
+      env["action_dispatch.content_security_policy"] = POLICY
+      env["action_dispatch.content_security_policy_report_only"] = false
+      env["action_dispatch.show_exceptions"] = false
+
+      @app.call(env)
+    end
+  end
+
+  APP = build_app(ROUTES) do |middleware|
+    middleware.use PolicyConfigMiddleware
+    middleware.use ActionDispatch::ContentSecurityPolicy::Middleware
+  end
+
+  def app
+    APP
+  end
+
+  def test_generates_content_security_policy_header
+    get "/"
+    assert_policy "default-src 'self';"
+  end
+
+  def test_generates_inline_content_security_policy
+    get "/inline"
+    assert_policy "default-src https://example.com;"
+  end
+
+  def test_generates_conditional_content_security_policy
+    get "/conditional", params: { condition: "true" }
+    assert_policy "default-src https://true.example.com;"
+
+    get "/conditional", params: { condition: "false" }
+    assert_policy "default-src https://false.example.com;"
+  end
+
+  def test_generates_report_only_content_security_policy
+    get "/report-only"
+    assert_policy "default-src 'self'; report-uri /violations;", report_only: true
+  end
+
+  private
+
+    def env_config
+      Rails.application.env_config
+    end
+
+    def content_security_policy
+      env_config["action_dispatch.content_security_policy"]
+    end
+
+    def content_security_policy=(policy)
+      env_config["action_dispatch.content_security_policy"] = policy
+    end
+
+    def assert_policy(expected, report_only: false)
+      assert_response :success
+
+      if report_only
+        expected_header = "Content-Security-Policy-Report-Only"
+        unexpected_header = "Content-Security-Policy"
+      else
+        expected_header = "Content-Security-Policy"
+        unexpected_header = "Content-Security-Policy-Report-Only"
+      end
+
+      assert_nil response.headers[unexpected_header]
+      assert_equal expected, response.headers[expected_header]
+    end
+end
diff --git a/actionpack/test/dispatch/cookies_test.rb b/actionpack/test/dispatch/cookies_test.rb
index c7194cde4a..40cbad3b0d 100644
--- a/actionpack/test/dispatch/cookies_test.rb
+++ b/actionpack/test/dispatch/cookies_test.rb
@@ -1,7 +1,9 @@
-require 'abstract_unit'
-require 'openssl'
-require 'active_support/key_generator'
-require 'active_support/message_verifier'
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "openssl"
+require "active_support/key_generator"
+require "active_support/messages/rotation_configuration"
 
 class CookieJarTest < ActiveSupport::TestCase
   attr_reader :request
@@ -12,26 +14,26 @@ class CookieJarTest < ActiveSupport::TestCase
 
   def test_fetch
     x = Object.new
-    assert_not request.cookie_jar.key?('zzzzzz')
-    assert_equal x, request.cookie_jar.fetch('zzzzzz', x)
-    assert_not request.cookie_jar.key?('zzzzzz')
+    assert_not request.cookie_jar.key?("zzzzzz")
+    assert_equal x, request.cookie_jar.fetch("zzzzzz", x)
+    assert_not request.cookie_jar.key?("zzzzzz")
   end
 
   def test_fetch_exists
     x = Object.new
-    request.cookie_jar['foo'] = 'bar'
-    assert_equal 'bar', request.cookie_jar.fetch('foo', x)
+    request.cookie_jar["foo"] = "bar"
+    assert_equal "bar", request.cookie_jar.fetch("foo", x)
   end
 
   def test_fetch_block
     x = Object.new
-    assert_not request.cookie_jar.key?('zzzzzz')
-    assert_equal x, request.cookie_jar.fetch('zzzzzz') { x }
+    assert_not request.cookie_jar.key?("zzzzzz")
+    assert_equal x, request.cookie_jar.fetch("zzzzzz") { x }
   end
 
   def test_key_is_to_s
-    request.cookie_jar['foo'] = 'bar'
-    assert_equal 'bar', request.cookie_jar.fetch(:foo)
+    request.cookie_jar["foo"] = "bar"
+    assert_equal "bar", request.cookie_jar.fetch(:foo)
   end
 
   def test_fetch_type_error
@@ -41,19 +43,19 @@ class CookieJarTest < ActiveSupport::TestCase
   end
 
   def test_each
-    request.cookie_jar['foo'] = :bar
+    request.cookie_jar["foo"] = :bar
     list = []
-    request.cookie_jar.each do |k,v|
+    request.cookie_jar.each do |k, v|
       list << [k, v]
     end
 
-    assert_equal [['foo', :bar]], list
+    assert_equal [["foo", :bar]], list
   end
 
   def test_enumerable
-    request.cookie_jar['foo'] = :bar
-    actual = request.cookie_jar.map { |k,v| [k.to_s, v.to_s] }
-    assert_equal [['foo', 'bar']], actual
+    request.cookie_jar["foo"] = :bar
+    actual = request.cookie_jar.map { |k, v| [k.to_s, v.to_s] }
+    assert_equal [["foo", "bar"]], actual
   end
 
   def test_key_methods
@@ -68,7 +70,7 @@ class CookieJarTest < ActiveSupport::TestCase
   def test_write_doesnt_set_a_nil_header
     headers = {}
     request.cookie_jar.write(headers)
-    assert !headers.include?('Set-Cookie')
+    assert_not_includes headers, "Set-Cookie"
   end
 end
 
@@ -95,17 +97,17 @@ class CookiesTest < ActionController::TestCase
     end
 
     def authenticate_for_fourteen_days
-      cookies["user_name"] = { "value" => "david", "expires" => Time.utc(2005, 10, 10,5) }
+      cookies["user_name"] = { "value" => "david", "expires" => Time.utc(2005, 10, 10, 5) }
       head :ok
     end
 
     def authenticate_for_fourteen_days_with_symbols
-      cookies[:user_name] = { :value => "david", :expires => Time.utc(2005, 10, 10,5) }
+      cookies[:user_name] = { value: "david", expires: Time.utc(2005, 10, 10, 5) }
       head :ok
     end
 
     def set_multiple_cookies
-      cookies["user_name"] = { "value" => "david", "expires" => Time.utc(2005, 10, 10,5) }
+      cookies["user_name"] = { "value" => "david", "expires" => Time.utc(2005, 10, 10, 5) }
       cookies["login"]     = "XJ-122"
       head :ok
     end
@@ -123,17 +125,17 @@ class CookiesTest < ActionController::TestCase
     alias delete_cookie logout
 
     def delete_cookie_with_path
-      cookies.delete("user_name", :path => '/beaten')
+      cookies.delete("user_name", path: "/beaten")
       head :ok
     end
 
     def authenticate_with_http_only
-      cookies["user_name"] = { :value => "david", :httponly => true }
+      cookies["user_name"] = { value: "david", httponly: true }
       head :ok
     end
 
     def authenticate_with_secure
-      cookies["user_name"] = { :value => "david", :secure => true }
+      cookies["user_name"] = { value: "david", secure: true }
       head :ok
     end
 
@@ -153,7 +155,7 @@ class CookiesTest < ActionController::TestCase
     end
 
     def set_encrypted_cookie
-      cookies.encrypted[:foo] = 'bar'
+      cookies.encrypted[:foo] = "bar"
       head :ok
     end
 
@@ -173,7 +175,7 @@ class CookiesTest < ActionController::TestCase
     end
 
     def set_wrapped_encrypted_cookie
-      cookies.encrypted[:foo] = JSONWrapper.new('bar')
+      cookies.encrypted[:foo] = JSONWrapper.new("bar")
       head :ok
     end
 
@@ -183,12 +185,12 @@ class CookiesTest < ActionController::TestCase
     end
 
     def set_invalid_encrypted_cookie
-      cookies[:invalid_cookie] = 'invalid--9170e00a57cfc27083363b5c75b835e477bd90cf'
+      cookies[:invalid_cookie] = "invalid--9170e00a57cfc27083363b5c75b835e477bd90cf"
       head :ok
     end
 
     def raise_data_overflow
-      cookies.signed[:foo] = 'bye!' * 1024
+      cookies.signed[:foo] = "bye!" * 1024
       head :ok
     end
 
@@ -205,47 +207,47 @@ class CookiesTest < ActionController::TestCase
 
     def delete_and_set_cookie
       cookies.delete :user_name
-      cookies[:user_name] = { :value => "david", :expires => Time.utc(2005, 10, 10,5) }
+      cookies[:user_name] = { value: "david", expires: Time.utc(2005, 10, 10, 5) }
       head :ok
     end
 
     def set_cookie_with_domain
-      cookies[:user_name] = {:value => "rizwanreza", :domain => :all}
+      cookies[:user_name] = { value: "rizwanreza", domain: :all }
       head :ok
     end
 
     def set_cookie_with_domain_all_as_string
-      cookies[:user_name] = {:value => "rizwanreza", :domain => 'all'}
+      cookies[:user_name] = { value: "rizwanreza", domain: "all" }
       head :ok
     end
 
     def delete_cookie_with_domain
-      cookies.delete(:user_name, :domain => :all)
+      cookies.delete(:user_name, domain: :all)
       head :ok
     end
 
     def delete_cookie_with_domain_all_as_string
-      cookies.delete(:user_name, :domain => 'all')
+      cookies.delete(:user_name, domain: "all")
       head :ok
     end
 
     def set_cookie_with_domain_and_tld
-      cookies[:user_name] = {:value => "rizwanreza", :domain => :all, :tld_length => 2}
+      cookies[:user_name] = { value: "rizwanreza", domain: :all, tld_length: 2 }
       head :ok
     end
 
     def delete_cookie_with_domain_and_tld
-      cookies.delete(:user_name, :domain => :all, :tld_length => 2)
+      cookies.delete(:user_name, domain: :all, tld_length: 2)
       head :ok
     end
 
     def set_cookie_with_domains
-      cookies[:user_name] = {:value => "rizwanreza", :domain => %w(example1.com example2.com .example3.com)}
+      cookies[:user_name] = { value: "rizwanreza", domain: %w(example1.com example2.com .example3.com) }
       head :ok
     end
 
     def delete_cookie_with_domains
-      cookies.delete(:user_name, :domain => %w(example1.com example2.com .example3.com))
+      cookies.delete(:user_name, domain: %w(example1.com example2.com .example3.com))
       head :ok
     end
 
@@ -255,7 +257,7 @@ class CookiesTest < ActionController::TestCase
     end
 
     def string_key
-      cookies['user_name'] = "dhh"
+      cookies["user_name"] = "dhh"
       head :ok
     end
 
@@ -265,27 +267,45 @@ class CookiesTest < ActionController::TestCase
     end
 
     def string_key_mock
-      cookies['user_name'] = "david" if cookies['user_name'] == "andrew"
+      cookies["user_name"] = "david" if cookies["user_name"] == "andrew"
       head :ok
     end
 
     def noop
       head :ok
     end
+
+    def encrypted_cookie
+      cookies.encrypted["foo"]
+    end
+
+    def cookie_expires_in_two_hours
+      cookies[:user_name] = { value: "assain", expires: 2.hours }
+      head :ok
+    end
   end
 
   tests TestController
 
-  SALT = 'b3c631c314c0bbca50c1b2843150fe33'
+  SECRET_KEY_BASE = "b3c631c314c0bbca50c1b2843150fe33"
+  SIGNED_COOKIE_SALT = "signed cookie"
+  ENCRYPTED_COOKIE_SALT = "encrypted cookie"
+  ENCRYPTED_SIGNED_COOKIE_SALT = "sigend encrypted cookie"
+  AUTHENTICATED_ENCRYPTED_COOKIE_SALT = "authenticated encrypted cookie"
 
   def setup
     super
 
-    @request.env["action_dispatch.key_generator"] = ActiveSupport::KeyGenerator.new(SALT, iterations: 2)
+    @request.env["action_dispatch.key_generator"] = ActiveSupport::KeyGenerator.new(SECRET_KEY_BASE, iterations: 2)
+    @request.env["action_dispatch.cookies_rotations"] = ActiveSupport::Messages::RotationConfiguration.new
 
-    @request.env["action_dispatch.signed_cookie_salt"] =
-      @request.env["action_dispatch.encrypted_cookie_salt"] =
-      @request.env["action_dispatch.encrypted_signed_cookie_salt"] = SALT
+    @request.env["action_dispatch.secret_key_base"] = SECRET_KEY_BASE
+    @request.env["action_dispatch.use_authenticated_cookie_encryption"] = true
+
+    @request.env["action_dispatch.signed_cookie_salt"] = SIGNED_COOKIE_SALT
+    @request.env["action_dispatch.encrypted_cookie_salt"] = ENCRYPTED_COOKIE_SALT
+    @request.env["action_dispatch.encrypted_signed_cookie_salt"] = ENCRYPTED_SIGNED_COOKIE_SALT
+    @request.env["action_dispatch.authenticated_encrypted_cookie_salt"] = AUTHENTICATED_ENCRYPTED_COOKIE_SALT
 
     @request.host = "www.nextangle.com"
   end
@@ -293,57 +313,57 @@ class CookiesTest < ActionController::TestCase
   def test_setting_cookie
     get :authenticate
     assert_cookie_header "user_name=david; path=/"
-    assert_equal({"user_name" => "david"}, @response.cookies)
+    assert_equal({ "user_name" => "david" }, @response.cookies)
   end
 
   def test_setting_the_same_value_to_cookie
-    request.cookies[:user_name] = 'david'
+    request.cookies[:user_name] = "david"
     get :authenticate
     assert_predicate response.cookies, :empty?
   end
 
   def test_setting_the_same_value_to_permanent_cookie
-    request.cookies[:user_name] = 'Jamie'
+    request.cookies[:user_name] = "Jamie"
     get :set_permanent_cookie
-    assert_equal({'user_name' => 'Jamie'}, response.cookies)
+    assert_equal({ "user_name" => "Jamie" }, response.cookies)
   end
 
   def test_setting_with_escapable_characters
     get :set_with_with_escapable_characters
     assert_cookie_header "that+%26+guy=foo+%26+bar+%3D%3E+baz; path=/"
-    assert_equal({"that & guy" => "foo & bar => baz"}, @response.cookies)
+    assert_equal({ "that & guy" => "foo & bar => baz" }, @response.cookies)
   end
 
   def test_setting_cookie_for_fourteen_days
     get :authenticate_for_fourteen_days
     assert_cookie_header "user_name=david; path=/; expires=Mon, 10 Oct 2005 05:00:00 -0000"
-    assert_equal({"user_name" => "david"}, @response.cookies)
+    assert_equal({ "user_name" => "david" }, @response.cookies)
   end
 
   def test_setting_cookie_for_fourteen_days_with_symbols
     get :authenticate_for_fourteen_days_with_symbols
     assert_cookie_header "user_name=david; path=/; expires=Mon, 10 Oct 2005 05:00:00 -0000"
-    assert_equal({"user_name" => "david"}, @response.cookies)
+    assert_equal({ "user_name" => "david" }, @response.cookies)
   end
 
   def test_setting_cookie_with_http_only
     get :authenticate_with_http_only
     assert_cookie_header "user_name=david; path=/; HttpOnly"
-    assert_equal({"user_name" => "david"}, @response.cookies)
+    assert_equal({ "user_name" => "david" }, @response.cookies)
   end
 
   def test_setting_cookie_with_secure
     @request.env["HTTPS"] = "on"
     get :authenticate_with_secure
     assert_cookie_header "user_name=david; path=/; secure"
-    assert_equal({"user_name" => "david"}, @response.cookies)
+    assert_equal({ "user_name" => "david" }, @response.cookies)
   end
 
   def test_setting_cookie_with_secure_when_always_write_cookie_is_true
     old_cookie, @request.cookie_jar.always_write_cookie = @request.cookie_jar.always_write_cookie, true
     get :authenticate_with_secure
     assert_cookie_header "user_name=david; path=/; secure"
-    assert_equal({"user_name" => "david"}, @response.cookies)
+    assert_equal({ "user_name" => "david" }, @response.cookies)
   ensure
     @request.cookie_jar.always_write_cookie = old_cookie
   end
@@ -351,14 +371,14 @@ class CookiesTest < ActionController::TestCase
   def test_not_setting_cookie_with_secure
     get :authenticate_with_secure
     assert_not_cookie_header "user_name=david; path=/; secure"
-    assert_not_equal({"user_name" => "david"}, @response.cookies)
+    assert_not_equal({ "user_name" => "david" }, @response.cookies)
   end
 
   def test_multiple_cookies
     get :set_multiple_cookies
     assert_equal 2, @response.cookies.size
     assert_cookie_header "user_name=david; path=/; expires=Mon, 10 Oct 2005 05:00:00 -0000\nlogin=XJ-122; path=/"
-    assert_equal({"login" => "XJ-122", "user_name" => "david"}, @response.cookies)
+    assert_equal({ "login" => "XJ-122", "user_name" => "david" }, @response.cookies)
   end
 
   def test_setting_test_cookie
@@ -366,14 +386,14 @@ class CookiesTest < ActionController::TestCase
   end
 
   def test_expiring_cookie
-    request.cookies[:user_name] = 'Joe'
+    request.cookies[:user_name] = "Joe"
     get :logout
     assert_cookie_header "user_name=; path=/; max-age=0; expires=Thu, 01 Jan 1970 00:00:00 -0000"
-    assert_equal({"user_name" => nil}, @response.cookies)
+    assert_equal({ "user_name" => nil }, @response.cookies)
   end
 
   def test_delete_cookie_with_path
-    request.cookies[:user_name] = 'Joe'
+    request.cookies[:user_name] = "Joe"
     get :delete_cookie_with_path
     assert_cookie_header "user_name=; path=/beaten; max-age=0; expires=Thu, 01 Jan 1970 00:00:00 -0000"
   end
@@ -385,16 +405,16 @@ class CookiesTest < ActionController::TestCase
   end
 
   def test_deleted_cookie_predicate
-    cookies[:user_name] = 'Joe'
+    cookies[:user_name] = "Joe"
     cookies.delete("user_name")
     assert cookies.deleted?("user_name")
     assert_equal false, cookies.deleted?("another")
   end
 
   def test_deleted_cookie_predicate_with_mismatching_options
-    cookies[:user_name] = 'Joe'
-    cookies.delete("user_name", :path => "/path")
-    assert_equal false, cookies.deleted?("user_name", :path => "/different")
+    cookies[:user_name] = "Joe"
+    cookies.delete("user_name", path: "/path")
+    assert_equal false, cookies.deleted?("user_name", path: "/different")
   end
 
   def test_cookies_persist_throughout_request
@@ -410,7 +430,7 @@ class CookiesTest < ActionController::TestCase
 
   def test_read_permanent_cookie
     get :set_permanent_cookie
-    assert_equal 'Jamie', @controller.send(:cookies).permanent[:user_name]
+    assert_equal "Jamie", @controller.send(:cookies).permanent[:user_name]
   end
 
   def test_signed_cookie_using_default_digest
@@ -420,28 +440,72 @@ class CookiesTest < ActionController::TestCase
     assert_equal 45, cookies.signed[:user_id]
 
     key_generator = @request.env["action_dispatch.key_generator"]
-    signed_cookie_salt = @request.env["action_dispatch.signed_cookie_salt"]
-    secret = key_generator.generate_key(signed_cookie_salt)
+    secret = key_generator.generate_key(@request.env["action_dispatch.signed_cookie_salt"])
 
-    verifier = ActiveSupport::MessageVerifier.new(secret, serializer: Marshal, digest: 'SHA1')
+    verifier = ActiveSupport::MessageVerifier.new(secret, serializer: Marshal, digest: "SHA1")
     assert_equal verifier.generate(45), cookies[:user_id]
   end
 
   def test_signed_cookie_using_custom_digest
-    @request.env["action_dispatch.cookies_digest"] = 'SHA256'
+    @request.env["action_dispatch.signed_cookie_digest"] = "SHA256"
+
     get :set_signed_cookie
     cookies = @controller.send :cookies
     assert_not_equal 45, cookies[:user_id]
     assert_equal 45, cookies.signed[:user_id]
 
     key_generator = @request.env["action_dispatch.key_generator"]
-    signed_cookie_salt = @request.env["action_dispatch.signed_cookie_salt"]
-    secret = key_generator.generate_key(signed_cookie_salt)
+    secret = key_generator.generate_key(@request.env["action_dispatch.signed_cookie_salt"])
 
-    verifier = ActiveSupport::MessageVerifier.new(secret, serializer: Marshal, digest: 'SHA256')
+    verifier = ActiveSupport::MessageVerifier.new(secret, serializer: Marshal, digest: "SHA256")
     assert_equal verifier.generate(45), cookies[:user_id]
   end
 
+  def test_signed_cookie_rotating_secret_and_digest
+    secret = "b3c631c314c0bbca50c1b2843150fe33"
+
+    @request.env["action_dispatch.signed_cookie_digest"] = "SHA256"
+    @request.env["action_dispatch.cookies_rotations"].rotate :signed, secret, digest: "SHA1"
+
+    old_message = ActiveSupport::MessageVerifier.new(secret, digest: "SHA1", serializer: Marshal).generate(45)
+    @request.headers["Cookie"] = "user_id=#{old_message}"
+
+    get :get_signed_cookie
+    assert_equal 45, @controller.send(:cookies).signed[:user_id]
+
+    key_generator = @request.env["action_dispatch.key_generator"]
+    secret = key_generator.generate_key(@request.env["action_dispatch.signed_cookie_salt"])
+    verifier = ActiveSupport::MessageVerifier.new(secret, digest: "SHA256", serializer: Marshal)
+    assert_equal 45, verifier.verify(@response.cookies["user_id"])
+  end
+
+  def test_signed_cookie_with_legacy_secret_scheme
+    @request.env["action_dispatch.secret_token"] = "b3c631c314c0bbca50c1b2843150fe33"
+
+    old_message = ActiveSupport::MessageVerifier.new("b3c631c314c0bbca50c1b2843150fe33", digest: "SHA1", serializer: Marshal).generate(45)
+
+    @request.headers["Cookie"] = "user_id=#{old_message}"
+    get :get_signed_cookie
+    assert_equal 45, @controller.send(:cookies).signed[:user_id]
+
+    key_generator = @request.env["action_dispatch.key_generator"]
+    secret = key_generator.generate_key("signed cookie")
+    verifier = ActiveSupport::MessageVerifier.new(secret, digest: "SHA1", serializer: Marshal)
+    assert_equal 45, verifier.verify(@response.cookies["user_id"])
+  end
+
+  def test_tampered_with_signed_cookie
+    key_generator = @request.env["action_dispatch.key_generator"]
+    secret = key_generator.generate_key(@request.env["action_dispatch.signed_cookie_salt"])
+
+    verifier = ActiveSupport::MessageVerifier.new(secret, serializer: Marshal, digest: "SHA1")
+    message = verifier.generate(45)
+
+    @request.headers["Cookie"] = "user_id=#{Marshal.dump 45}--#{message.split("--").last}"
+    get :get_signed_cookie
+    assert_nil @controller.send(:cookies).signed[:user_id]
+  end
+
   def test_signed_cookie_using_default_serializer
     get :set_signed_cookie
     cookies = @controller.send :cookies
@@ -469,23 +533,22 @@ class CookiesTest < ActionController::TestCase
     @request.env["action_dispatch.cookies_serializer"] = :json
     get :set_wrapped_signed_cookie
     cookies = @controller.send :cookies
-    assert_not_equal 'wrapped: 45', cookies[:user_id]
-    assert_equal 'wrapped: 45', cookies.signed[:user_id]
+    assert_not_equal "wrapped: 45", cookies[:user_id]
+    assert_equal "wrapped: 45", cookies.signed[:user_id]
   end
 
   def test_signed_cookie_using_custom_serializer
     @request.env["action_dispatch.cookies_serializer"] = CustomSerializer
     get :set_signed_cookie
     assert_not_equal 45, cookies[:user_id]
-    assert_equal '45 was dumped and loaded', cookies.signed[:user_id]
+    assert_equal "45 was dumped and loaded", cookies.signed[:user_id]
   end
 
   def test_signed_cookie_using_hybrid_serializer_can_migrate_marshal_dumped_value_to_json
     @request.env["action_dispatch.cookies_serializer"] = :hybrid
 
     key_generator = @request.env["action_dispatch.key_generator"]
-    signed_cookie_salt = @request.env["action_dispatch.signed_cookie_salt"]
-    secret = key_generator.generate_key(signed_cookie_salt)
+    secret = key_generator.generate_key(@request.env["action_dispatch.signed_cookie_salt"])
 
     marshal_value = ActiveSupport::MessageVerifier.new(secret, serializer: Marshal).generate(45)
     @request.headers["Cookie"] = "user_id=#{marshal_value}"
@@ -497,15 +560,15 @@ class CookiesTest < ActionController::TestCase
     assert_equal 45, cookies.signed[:user_id]
 
     verifier = ActiveSupport::MessageVerifier.new(secret, serializer: JSON)
-    assert_equal 45, verifier.verify(@response.cookies['user_id'])
+    assert_equal 45, verifier.verify(@response.cookies["user_id"])
   end
 
   def test_signed_cookie_using_hybrid_serializer_can_read_from_json_dumped_value
     @request.env["action_dispatch.cookies_serializer"] = :hybrid
 
     key_generator = @request.env["action_dispatch.key_generator"]
-    signed_cookie_salt = @request.env["action_dispatch.signed_cookie_salt"]
-    secret = key_generator.generate_key(signed_cookie_salt)
+    secret = key_generator.generate_key(@request.env["action_dispatch.signed_cookie_salt"])
+
     json_value = ActiveSupport::MessageVerifier.new(secret, serializer: JSON).generate(45)
     @request.headers["Cookie"] = "user_id=#{json_value}"
 
@@ -526,85 +589,54 @@ class CookiesTest < ActionController::TestCase
   def test_encrypted_cookie_using_default_serializer
     get :set_encrypted_cookie
     cookies = @controller.send :cookies
-    assert_not_equal 'bar', cookies[:foo]
-    assert_raise TypeError do
-      cookies.signed[:foo]
-    end
-    assert_equal 'bar', cookies.encrypted[:foo]
+    assert_not_equal "bar", cookies[:foo]
+    assert_nil cookies.signed[:foo]
+    assert_equal "bar", cookies.encrypted[:foo]
   end
 
   def test_encrypted_cookie_using_marshal_serializer
     @request.env["action_dispatch.cookies_serializer"] = :marshal
     get :set_encrypted_cookie
     cookies = @controller.send :cookies
-    assert_not_equal 'bar', cookies[:foo]
-    assert_raises TypeError do
-      cookies.signed[:foo]
-    end
-    assert_equal 'bar', cookies.encrypted[:foo]
+    assert_not_equal "bar", cookies[:foo]
+    assert_nil cookies.signed[:foo]
+    assert_equal "bar", cookies.encrypted[:foo]
   end
 
   def test_encrypted_cookie_using_json_serializer
     @request.env["action_dispatch.cookies_serializer"] = :json
     get :set_encrypted_cookie
     cookies = @controller.send :cookies
-    assert_not_equal 'bar', cookies[:foo]
-    assert_raises ::JSON::ParserError do
-      cookies.signed[:foo]
-    end
-    assert_equal 'bar', cookies.encrypted[:foo]
+    assert_not_equal "bar", cookies[:foo]
+    assert_nil cookies.signed[:foo]
+    assert_equal "bar", cookies.encrypted[:foo]
   end
 
   def test_wrapped_encrypted_cookie_using_json_serializer
     @request.env["action_dispatch.cookies_serializer"] = :json
     get :set_wrapped_encrypted_cookie
     cookies = @controller.send :cookies
-    assert_not_equal 'wrapped: bar', cookies[:foo]
-    assert_raises ::JSON::ParserError do
-      cookies.signed[:foo]
-    end
-    assert_equal 'wrapped: bar', cookies.encrypted[:foo]
+    assert_not_equal "wrapped: bar", cookies[:foo]
+    assert_nil cookies.signed[:foo]
+    assert_equal "wrapped: bar", cookies.encrypted[:foo]
   end
 
   def test_encrypted_cookie_using_custom_serializer
     @request.env["action_dispatch.cookies_serializer"] = CustomSerializer
     get :set_encrypted_cookie
-    assert_not_equal 'bar', cookies.encrypted[:foo]
-    assert_equal 'bar was dumped and loaded', cookies.encrypted[:foo]
-  end
-
-  def test_encrypted_cookie_using_custom_digest
-    @request.env["action_dispatch.cookies_digest"] = 'SHA256'
-    get :set_encrypted_cookie
-    cookies = @controller.send :cookies
-    assert_not_equal 'bar', cookies[:foo]
-    assert_equal 'bar', cookies.encrypted[:foo]
-
-    sign_secret = @request.env["action_dispatch.key_generator"].generate_key(@request.env["action_dispatch.encrypted_signed_cookie_salt"])
-
-    sha1_verifier   = ActiveSupport::MessageVerifier.new(sign_secret, serializer: ActiveSupport::MessageEncryptor::NullSerializer, digest: 'SHA1')
-    sha256_verifier = ActiveSupport::MessageVerifier.new(sign_secret, serializer: ActiveSupport::MessageEncryptor::NullSerializer, digest: 'SHA256')
-
-    assert_raises(ActiveSupport::MessageVerifier::InvalidSignature) do
-      sha1_verifier.verify(cookies[:foo])
-    end
-
-    assert_nothing_raised do
-      sha256_verifier.verify(cookies[:foo])
-    end
+    assert_not_equal "bar", cookies.encrypted[:foo]
+    assert_equal "bar was dumped and loaded", cookies.encrypted[:foo]
   end
 
   def test_encrypted_cookie_using_hybrid_serializer_can_migrate_marshal_dumped_value_to_json
     @request.env["action_dispatch.cookies_serializer"] = :hybrid
 
     key_generator = @request.env["action_dispatch.key_generator"]
-    encrypted_cookie_salt = @request.env["action_dispatch.encrypted_cookie_salt"]
-    encrypted_signed_cookie_salt = @request.env["action_dispatch.encrypted_signed_cookie_salt"]
-    secret = key_generator.generate_key(encrypted_cookie_salt)
-    sign_secret = key_generator.generate_key(encrypted_signed_cookie_salt)
+    secret = key_generator.generate_key(@request.env["action_dispatch.authenticated_encrypted_cookie_salt"], 32)
 
-    marshal_value = ActiveSupport::MessageEncryptor.new(secret, sign_secret, serializer: Marshal).encrypt_and_sign("bar")
-    @request.headers["Cookie"] = "foo=#{marshal_value}"
+    encryptor = ActiveSupport::MessageEncryptor.new(secret, cipher: "aes-256-gcm", serializer: Marshal)
+    marshal_value = encryptor.encrypt_and_sign("bar")
+    @request.headers["Cookie"] = "foo=#{::Rack::Utils.escape marshal_value}"
 
     get :get_encrypted_cookie
 
@@ -612,20 +644,20 @@ class CookiesTest < ActionController::TestCase
     assert_not_equal "bar", cookies[:foo]
     assert_equal "bar", cookies.encrypted[:foo]
 
-    encryptor = ActiveSupport::MessageEncryptor.new(secret, sign_secret, serializer: JSON)
-    assert_equal "bar", encryptor.decrypt_and_verify(@response.cookies["foo"])
+    json_encryptor = ActiveSupport::MessageEncryptor.new(secret, cipher: "aes-256-gcm", serializer: JSON)
+    assert_not_nil @response.cookies["foo"]
+    assert_equal "bar", json_encryptor.decrypt_and_verify(@response.cookies["foo"])
   end
 
   def test_encrypted_cookie_using_hybrid_serializer_can_read_from_json_dumped_value
     @request.env["action_dispatch.cookies_serializer"] = :hybrid
 
     key_generator = @request.env["action_dispatch.key_generator"]
-    encrypted_cookie_salt = @request.env["action_dispatch.encrypted_cookie_salt"]
-    encrypted_signed_cookie_salt = @request.env["action_dispatch.encrypted_signed_cookie_salt"]
-    secret = key_generator.generate_key(encrypted_cookie_salt)
-    sign_secret = key_generator.generate_key(encrypted_signed_cookie_salt)
-    json_value = ActiveSupport::MessageEncryptor.new(secret, sign_secret, serializer: JSON).encrypt_and_sign("bar")
-    @request.headers["Cookie"] = "foo=#{json_value}"
+    secret = key_generator.generate_key(@request.env["action_dispatch.authenticated_encrypted_cookie_salt"], 32)
+
+    encryptor = ActiveSupport::MessageEncryptor.new(secret, cipher: "aes-256-gcm", serializer: JSON)
+    json_value = encryptor.encrypt_and_sign("bar")
+    @request.headers["Cookie"] = "foo=#{::Rack::Utils.escape json_value}"
 
     get :get_encrypted_cookie
 
@@ -653,10 +685,10 @@ class CookiesTest < ActionController::TestCase
   end
 
   def test_delete_and_set_cookie
-    request.cookies[:user_name] = 'Joe'
+    request.cookies[:user_name] = "Joe"
     get :delete_and_set_cookie
     assert_cookie_header "user_name=david; path=/; expires=Mon, 10 Oct 2005 05:00:00 -0000"
-    assert_equal({"user_name" => "david"}, @response.cookies)
+    assert_equal({ "user_name" => "david" }, @response.cookies)
   end
 
   def test_raise_data_overflow
@@ -687,7 +719,7 @@ class CookiesTest < ActionController::TestCase
       get :set_signed_cookie
     }
 
-    assert_raise(ArgumentError, ''.inspect) {
+    assert_raise(ArgumentError, "".inspect) {
       @request.env["action_dispatch.key_generator"] = ActiveSupport::LegacyKeyGenerator.new("")
       get :set_signed_cookie
     }
@@ -710,65 +742,8 @@ class CookiesTest < ActionController::TestCase
     }
   end
 
-  def test_signed_uses_signed_cookie_jar_if_only_secret_token_is_set
-    @request.env["action_dispatch.secret_token"] = "b3c631c314c0bbca50c1b2843150fe33"
-    @request.env["action_dispatch.secret_key_base"] = nil
-    get :set_signed_cookie
-    assert_kind_of ActionDispatch::Cookies::SignedCookieJar, cookies.signed
-  end
-
-  def test_signed_uses_signed_cookie_jar_if_only_secret_key_base_is_set
-    @request.env["action_dispatch.secret_token"] = nil
-    @request.env["action_dispatch.secret_key_base"] = "c3b95688f35581fad38df788add315ff"
-    get :set_signed_cookie
-    assert_kind_of ActionDispatch::Cookies::SignedCookieJar, cookies.signed
-  end
-
-  def test_signed_uses_upgrade_legacy_signed_cookie_jar_if_both_secret_token_and_secret_key_base_are_set
-    @request.env["action_dispatch.secret_token"] = "b3c631c314c0bbca50c1b2843150fe33"
-    @request.env["action_dispatch.secret_key_base"] = "c3b95688f35581fad38df788add315ff"
-    get :set_signed_cookie
-    assert_kind_of ActionDispatch::Cookies::UpgradeLegacySignedCookieJar, cookies.signed
-  end
-
-  def test_signed_or_encrypted_uses_signed_cookie_jar_if_only_secret_token_is_set
-    @request.env["action_dispatch.secret_token"] = "b3c631c314c0bbca50c1b2843150fe33"
-    @request.env["action_dispatch.secret_key_base"] = nil
-    get :get_encrypted_cookie
-    assert_kind_of ActionDispatch::Cookies::SignedCookieJar, cookies.signed_or_encrypted
-  end
-
-  def test_signed_or_encrypted_uses_encrypted_cookie_jar_if_only_secret_key_base_is_set
-    @request.env["action_dispatch.secret_token"] = nil
-    @request.env["action_dispatch.secret_key_base"] = "c3b95688f35581fad38df788add315ff"
-    get :get_encrypted_cookie
-    assert_kind_of ActionDispatch::Cookies::EncryptedCookieJar, cookies.signed_or_encrypted
-  end
-
-  def test_signed_or_encrypted_uses_upgrade_legacy_encrypted_cookie_jar_if_both_secret_token_and_secret_key_base_are_set
-    @request.env["action_dispatch.secret_token"] = "b3c631c314c0bbca50c1b2843150fe33"
-    @request.env["action_dispatch.secret_key_base"] = "c3b95688f35581fad38df788add315ff"
-    get :get_encrypted_cookie
-    assert_kind_of ActionDispatch::Cookies::UpgradeLegacyEncryptedCookieJar, cookies.signed_or_encrypted
-  end
-
-  def test_encrypted_uses_encrypted_cookie_jar_if_only_secret_key_base_is_set
-    @request.env["action_dispatch.secret_token"] = nil
-    @request.env["action_dispatch.secret_key_base"] = "c3b95688f35581fad38df788add315ff"
-    get :get_encrypted_cookie
-    assert_kind_of ActionDispatch::Cookies::EncryptedCookieJar, cookies.encrypted
-  end
-
-  def test_encrypted_uses_upgrade_legacy_encrypted_cookie_jar_if_both_secret_token_and_secret_key_base_are_set
-    @request.env["action_dispatch.secret_token"] = "b3c631c314c0bbca50c1b2843150fe33"
-    @request.env["action_dispatch.secret_key_base"] = "c3b95688f35581fad38df788add315ff"
-    get :get_encrypted_cookie
-    assert_kind_of ActionDispatch::Cookies::UpgradeLegacyEncryptedCookieJar, cookies.encrypted
-  end
-
   def test_legacy_signed_cookie_is_read_and_transparently_upgraded_by_signed_cookie_jar_if_both_secret_token_and_secret_key_base_are_set
     @request.env["action_dispatch.secret_token"] = "b3c631c314c0bbca50c1b2843150fe33"
-    @request.env["action_dispatch.secret_key_base"] = "c3b95688f35581fad38df788add315ff"
 
     legacy_value = ActiveSupport::MessageVerifier.new("b3c631c314c0bbca50c1b2843150fe33").generate(45)
 
@@ -785,28 +760,22 @@ class CookiesTest < ActionController::TestCase
 
   def test_legacy_signed_cookie_is_read_and_transparently_encrypted_by_encrypted_cookie_jar_if_both_secret_token_and_secret_key_base_are_set
     @request.env["action_dispatch.secret_token"] = "b3c631c314c0bbca50c1b2843150fe33"
-    @request.env["action_dispatch.secret_key_base"] = "c3b95688f35581fad38df788add315ff"
-    @request.env["action_dispatch.encrypted_cookie_salt"] = "4433796b79d99a7735553e316522acee"
-    @request.env["action_dispatch.encrypted_signed_cookie_salt"] = "00646eb40062e1b1deff205a27cd30f9"
 
-    legacy_value = ActiveSupport::MessageVerifier.new("b3c631c314c0bbca50c1b2843150fe33").generate('bar')
+    legacy_value = ActiveSupport::MessageVerifier.new("b3c631c314c0bbca50c1b2843150fe33").generate("bar")
 
     @request.headers["Cookie"] = "foo=#{legacy_value}"
     get :get_encrypted_cookie
 
-    assert_equal 'bar', @controller.send(:cookies).encrypted[:foo]
+    assert_equal "bar", @controller.send(:cookies).encrypted[:foo]
 
-    key_generator = @request.env["action_dispatch.key_generator"]
-    secret = key_generator.generate_key(@request.env["action_dispatch.encrypted_cookie_salt"])
-    sign_secret = key_generator.generate_key(@request.env["action_dispatch.encrypted_signed_cookie_salt"])
-    encryptor = ActiveSupport::MessageEncryptor.new(secret, sign_secret)
-    assert_equal 'bar', encryptor.decrypt_and_verify(@response.cookies["foo"])
+    secret = @request.env["action_dispatch.key_generator"].generate_key(@request.env["action_dispatch.authenticated_encrypted_cookie_salt"], 32)
+    encryptor = ActiveSupport::MessageEncryptor.new(secret, cipher: "aes-256-gcm", serializer: Marshal)
+    assert_equal "bar", encryptor.decrypt_and_verify(@response.cookies["foo"])
   end
 
   def test_legacy_json_signed_cookie_is_read_and_transparently_upgraded_by_signed_json_cookie_jar_if_both_secret_token_and_secret_key_base_are_set
     @request.env["action_dispatch.cookies_serializer"] = :json
     @request.env["action_dispatch.secret_token"] = "b3c631c314c0bbca50c1b2843150fe33"
-    @request.env["action_dispatch.secret_key_base"] = "c3b95688f35581fad38df788add315ff"
 
     legacy_value = ActiveSupport::MessageVerifier.new("b3c631c314c0bbca50c1b2843150fe33", serializer: JSON).generate(45)
 
@@ -824,28 +793,24 @@ class CookiesTest < ActionController::TestCase
   def test_legacy_json_signed_cookie_is_read_and_transparently_encrypted_by_encrypted_json_cookie_jar_if_both_secret_token_and_secret_key_base_are_set
     @request.env["action_dispatch.cookies_serializer"] = :json
     @request.env["action_dispatch.secret_token"] = "b3c631c314c0bbca50c1b2843150fe33"
-    @request.env["action_dispatch.secret_key_base"] = "c3b95688f35581fad38df788add315ff"
-    @request.env["action_dispatch.encrypted_cookie_salt"] = "4433796b79d99a7735553e316522acee"
-    @request.env["action_dispatch.encrypted_signed_cookie_salt"] = "00646eb40062e1b1deff205a27cd30f9"
 
-    legacy_value = ActiveSupport::MessageVerifier.new("b3c631c314c0bbca50c1b2843150fe33", serializer: JSON).generate('bar')
+    legacy_value = ActiveSupport::MessageVerifier.new("b3c631c314c0bbca50c1b2843150fe33", serializer: JSON).generate("bar")
 
     @request.headers["Cookie"] = "foo=#{legacy_value}"
     get :get_encrypted_cookie
 
-    assert_equal 'bar', @controller.send(:cookies).encrypted[:foo]
+    assert_equal "bar", @controller.send(:cookies).encrypted[:foo]
 
-    key_generator = @request.env["action_dispatch.key_generator"]
-    secret = key_generator.generate_key(@request.env["action_dispatch.encrypted_cookie_salt"])
-    sign_secret = key_generator.generate_key(@request.env["action_dispatch.encrypted_signed_cookie_salt"])
-    encryptor = ActiveSupport::MessageEncryptor.new(secret, sign_secret, serializer: JSON)
-    assert_equal 'bar', encryptor.decrypt_and_verify(@response.cookies["foo"])
+    cipher = "aes-256-gcm"
+    salt = @request.env["action_dispatch.authenticated_encrypted_cookie_salt"]
+    secret = @request.env["action_dispatch.key_generator"].generate_key(salt)[0, ActiveSupport::MessageEncryptor.key_len(cipher)]
+    encryptor = ActiveSupport::MessageEncryptor.new(secret, cipher: cipher, serializer: JSON)
+    assert_equal "bar", encryptor.decrypt_and_verify(@response.cookies["foo"])
   end
 
   def test_legacy_json_signed_cookie_is_read_and_transparently_upgraded_by_signed_json_hybrid_jar_if_both_secret_token_and_secret_key_base_are_set
     @request.env["action_dispatch.cookies_serializer"] = :hybrid
     @request.env["action_dispatch.secret_token"] = "b3c631c314c0bbca50c1b2843150fe33"
-    @request.env["action_dispatch.secret_key_base"] = "c3b95688f35581fad38df788add315ff"
 
     legacy_value = ActiveSupport::MessageVerifier.new("b3c631c314c0bbca50c1b2843150fe33", serializer: JSON).generate(45)
 
@@ -863,28 +828,23 @@ class CookiesTest < ActionController::TestCase
   def test_legacy_json_signed_cookie_is_read_and_transparently_encrypted_by_encrypted_hybrid_cookie_jar_if_both_secret_token_and_secret_key_base_are_set
     @request.env["action_dispatch.cookies_serializer"] = :hybrid
     @request.env["action_dispatch.secret_token"] = "b3c631c314c0bbca50c1b2843150fe33"
-    @request.env["action_dispatch.secret_key_base"] = "c3b95688f35581fad38df788add315ff"
-    @request.env["action_dispatch.encrypted_cookie_salt"] = "4433796b79d99a7735553e316522acee"
-    @request.env["action_dispatch.encrypted_signed_cookie_salt"] = "00646eb40062e1b1deff205a27cd30f9"
 
-    legacy_value = ActiveSupport::MessageVerifier.new("b3c631c314c0bbca50c1b2843150fe33", serializer: JSON).generate('bar')
+    legacy_value = ActiveSupport::MessageVerifier.new("b3c631c314c0bbca50c1b2843150fe33", serializer: JSON).generate("bar")
 
     @request.headers["Cookie"] = "foo=#{legacy_value}"
     get :get_encrypted_cookie
 
-    assert_equal 'bar', @controller.send(:cookies).encrypted[:foo]
+    assert_equal "bar", @controller.send(:cookies).encrypted[:foo]
 
-    key_generator = @request.env["action_dispatch.key_generator"]
-    secret = key_generator.generate_key(@request.env["action_dispatch.encrypted_cookie_salt"])
-    sign_secret = key_generator.generate_key(@request.env["action_dispatch.encrypted_signed_cookie_salt"])
-    encryptor = ActiveSupport::MessageEncryptor.new(secret, sign_secret, serializer: JSON)
-    assert_equal 'bar', encryptor.decrypt_and_verify(@response.cookies["foo"])
+    salt = @request.env["action_dispatch.authenticated_encrypted_cookie_salt"]
+    secret = @request.env["action_dispatch.key_generator"].generate_key(salt)[0, ActiveSupport::MessageEncryptor.key_len("aes-256-gcm")]
+    encryptor = ActiveSupport::MessageEncryptor.new(secret, cipher: "aes-256-gcm", serializer: JSON)
+    assert_equal "bar", encryptor.decrypt_and_verify(@response.cookies["foo"])
   end
 
   def test_legacy_marshal_signed_cookie_is_read_and_transparently_upgraded_by_signed_json_hybrid_jar_if_both_secret_token_and_secret_key_base_are_set
     @request.env["action_dispatch.cookies_serializer"] = :hybrid
     @request.env["action_dispatch.secret_token"] = "b3c631c314c0bbca50c1b2843150fe33"
-    @request.env["action_dispatch.secret_key_base"] = "c3b95688f35581fad38df788add315ff"
 
     legacy_value = ActiveSupport::MessageVerifier.new("b3c631c314c0bbca50c1b2843150fe33").generate(45)
 
@@ -901,45 +861,170 @@ class CookiesTest < ActionController::TestCase
 
   def test_legacy_marshal_signed_cookie_is_read_and_transparently_encrypted_by_encrypted_hybrid_cookie_jar_if_both_secret_token_and_secret_key_base_are_set
     @request.env["action_dispatch.cookies_serializer"] = :hybrid
+
+    @request.env["action_dispatch.use_authenticated_cookie_encryption"] = true
     @request.env["action_dispatch.secret_token"] = "b3c631c314c0bbca50c1b2843150fe33"
     @request.env["action_dispatch.secret_key_base"] = "c3b95688f35581fad38df788add315ff"
-    @request.env["action_dispatch.encrypted_cookie_salt"] = "4433796b79d99a7735553e316522acee"
-    @request.env["action_dispatch.encrypted_signed_cookie_salt"] = "00646eb40062e1b1deff205a27cd30f9"
 
-    legacy_value = ActiveSupport::MessageVerifier.new("b3c631c314c0bbca50c1b2843150fe33").generate('bar')
+    legacy_value = ActiveSupport::MessageVerifier.new("b3c631c314c0bbca50c1b2843150fe33").generate("bar")
 
     @request.headers["Cookie"] = "foo=#{legacy_value}"
     get :get_encrypted_cookie
 
-    assert_equal 'bar', @controller.send(:cookies).encrypted[:foo]
+    assert_equal "bar", @controller.send(:cookies).encrypted[:foo]
 
-    key_generator = @request.env["action_dispatch.key_generator"]
-    secret = key_generator.generate_key(@request.env["action_dispatch.encrypted_cookie_salt"])
-    sign_secret = key_generator.generate_key(@request.env["action_dispatch.encrypted_signed_cookie_salt"])
-    encryptor = ActiveSupport::MessageEncryptor.new(secret, sign_secret, serializer: JSON)
-    assert_equal 'bar', encryptor.decrypt_and_verify(@response.cookies["foo"])
+    salt = @request.env["action_dispatch.authenticated_encrypted_cookie_salt"]
+    secret = @request.env["action_dispatch.key_generator"].generate_key(salt)[0, ActiveSupport::MessageEncryptor.key_len("aes-256-gcm")]
+    encryptor = ActiveSupport::MessageEncryptor.new(secret, cipher: "aes-256-gcm", serializer: JSON)
+    assert_equal "bar", encryptor.decrypt_and_verify(@response.cookies["foo"])
   end
 
   def test_legacy_signed_cookie_is_treated_as_nil_by_signed_cookie_jar_if_tampered
     @request.env["action_dispatch.secret_token"] = "b3c631c314c0bbca50c1b2843150fe33"
-    @request.env["action_dispatch.secret_key_base"] = "c3b95688f35581fad38df788add315ff"
 
     @request.headers["Cookie"] = "user_id=45"
     get :get_signed_cookie
 
-    assert_equal nil, @controller.send(:cookies).signed[:user_id]
-    assert_equal nil, @response.cookies["user_id"]
+    assert_nil @controller.send(:cookies).signed[:user_id]
+    assert_nil @response.cookies["user_id"]
   end
 
   def test_legacy_signed_cookie_is_treated_as_nil_by_encrypted_cookie_jar_if_tampered
     @request.env["action_dispatch.secret_token"] = "b3c631c314c0bbca50c1b2843150fe33"
-    @request.env["action_dispatch.secret_key_base"] = "c3b95688f35581fad38df788add315ff"
 
     @request.headers["Cookie"] = "foo=baz"
     get :get_encrypted_cookie
 
-    assert_equal nil, @controller.send(:cookies).encrypted[:foo]
-    assert_equal nil, @response.cookies["foo"]
+    assert_nil @controller.send(:cookies).encrypted[:foo]
+    assert_nil @response.cookies["foo"]
+  end
+
+  def test_use_authenticated_cookie_encryption_uses_legacy_hmac_aes_cbc_encryption_when_not_enabled
+    @request.env["action_dispatch.use_authenticated_cookie_encryption"] = nil
+
+    key_generator = @request.env["action_dispatch.key_generator"]
+    encrypted_cookie_salt = @request.env["action_dispatch.encrypted_cookie_salt"]
+    encrypted_signed_cookie_salt = @request.env["action_dispatch.encrypted_signed_cookie_salt"]
+    secret = key_generator.generate_key(encrypted_cookie_salt, ActiveSupport::MessageEncryptor.key_len("aes-256-cbc"))
+    sign_secret = key_generator.generate_key(encrypted_signed_cookie_salt)
+    encryptor = ActiveSupport::MessageEncryptor.new(secret, sign_secret, cipher: "aes-256-cbc", digest: "SHA1", serializer: Marshal)
+
+    get :set_encrypted_cookie
+
+    cookies = @controller.send :cookies
+    assert_not_equal "bar", cookies[:foo]
+    assert_equal "bar", cookies.encrypted[:foo]
+    assert_equal "bar", encryptor.decrypt_and_verify(@response.cookies["foo"])
+  end
+
+  def test_rotating_signed_cookies_digest
+    @request.env["action_dispatch.signed_cookie_digest"] = "SHA256"
+    @request.env["action_dispatch.cookies_rotations"].rotate :signed, digest: "SHA1"
+
+    key_generator = @request.env["action_dispatch.key_generator"]
+
+    old_secret = key_generator.generate_key(@request.env["action_dispatch.signed_cookie_salt"])
+    old_value = ActiveSupport::MessageVerifier.new(old_secret).generate(45)
+
+    @request.headers["Cookie"] = "user_id=#{old_value}"
+    get :get_signed_cookie
+
+    assert_equal 45, @controller.send(:cookies).signed[:user_id]
+
+    secret = key_generator.generate_key(@request.env["action_dispatch.signed_cookie_salt"])
+    verifier = ActiveSupport::MessageVerifier.new(secret, digest: "SHA256")
+    assert_equal 45, verifier.verify(@response.cookies["user_id"])
+  end
+
+  def test_legacy_hmac_aes_cbc_encrypted_marshal_cookie_is_upgraded_to_authenticated_encrypted_cookie
+    key_generator = @request.env["action_dispatch.key_generator"]
+    encrypted_cookie_salt = @request.env["action_dispatch.encrypted_cookie_salt"]
+    encrypted_signed_cookie_salt = @request.env["action_dispatch.encrypted_signed_cookie_salt"]
+    secret = key_generator.generate_key(encrypted_cookie_salt, ActiveSupport::MessageEncryptor.key_len("aes-256-cbc"))
+    sign_secret = key_generator.generate_key(encrypted_signed_cookie_salt)
+    marshal_value = ActiveSupport::MessageEncryptor.new(secret, sign_secret, cipher: "aes-256-cbc", serializer: Marshal).encrypt_and_sign("bar")
+
+    @request.headers["Cookie"] = "foo=#{marshal_value}"
+
+    get :get_encrypted_cookie
+
+    cookies = @controller.send :cookies
+    assert_not_equal "bar", cookies[:foo]
+    assert_equal "bar", cookies.encrypted[:foo]
+
+    aead_salt = @request.env["action_dispatch.authenticated_encrypted_cookie_salt"]
+    aead_secret = key_generator.generate_key(aead_salt, ActiveSupport::MessageEncryptor.key_len("aes-256-gcm"))
+    aead_encryptor = ActiveSupport::MessageEncryptor.new(aead_secret, cipher: "aes-256-gcm", serializer: Marshal)
+
+    assert_equal "bar", aead_encryptor.decrypt_and_verify(@response.cookies["foo"])
+  end
+
+  def test_legacy_hmac_aes_cbc_encrypted_json_cookie_is_upgraded_to_authenticated_encrypted_cookie
+    @request.env["action_dispatch.cookies_serializer"] = :json
+
+    key_generator = @request.env["action_dispatch.key_generator"]
+    encrypted_cookie_salt = @request.env["action_dispatch.encrypted_cookie_salt"]
+    encrypted_signed_cookie_salt = @request.env["action_dispatch.encrypted_signed_cookie_salt"]
+    secret = key_generator.generate_key(encrypted_cookie_salt, ActiveSupport::MessageEncryptor.key_len("aes-256-cbc"))
+    sign_secret = key_generator.generate_key(encrypted_signed_cookie_salt)
+    marshal_value = ActiveSupport::MessageEncryptor.new(secret, sign_secret, cipher: "aes-256-cbc", serializer: JSON).encrypt_and_sign("bar")
+
+    @request.headers["Cookie"] = "foo=#{marshal_value}"
+
+    get :get_encrypted_cookie
+
+    cookies = @controller.send :cookies
+    assert_not_equal "bar", cookies[:foo]
+    assert_equal "bar", cookies.encrypted[:foo]
+
+    aead_salt = @request.env["action_dispatch.authenticated_encrypted_cookie_salt"]
+    aead_secret = key_generator.generate_key(aead_salt)[0, ActiveSupport::MessageEncryptor.key_len("aes-256-gcm")]
+    aead_encryptor = ActiveSupport::MessageEncryptor.new(aead_secret, cipher: "aes-256-gcm", serializer: JSON)
+
+    assert_equal "bar", aead_encryptor.decrypt_and_verify(@response.cookies["foo"])
+  end
+
+  def test_legacy_hmac_aes_cbc_encrypted_cookie_using_64_byte_key_is_upgraded_to_authenticated_encrypted_cookie
+    @request.env["action_dispatch.secret_key_base"] = "c3b95688f35581fad38df788add315ff"
+    @request.env["action_dispatch.encrypted_cookie_salt"] = "b3c631c314c0bbca50c1b2843150fe33"
+    @request.env["action_dispatch.encrypted_signed_cookie_salt"] = "b3c631c314c0bbca50c1b2843150fe33"
+
+    # Cookie generated with 64 bytes secret
+    message = ["566d4e75536d686e633246564e6b493062557079626c566d51574d30515430394c53315665564a694e4563786555744f57537454576b396a5a31566a626e52525054303d2d2d34663234333330623130623261306163363562316266323335396164666364613564643134623131"].pack("H*")
+    @request.headers["Cookie"] = "foo=#{message}"
+
+    get :get_encrypted_cookie
+
+    cookies = @controller.send :cookies
+    assert_not_equal "bar", cookies[:foo]
+    assert_equal "bar", cookies.encrypted[:foo]
+
+    salt = @request.env["action_dispatch.authenticated_encrypted_cookie_salt"]
+    secret = @request.env["action_dispatch.key_generator"].generate_key(salt, ActiveSupport::MessageEncryptor.key_len("aes-256-gcm"))
+    encryptor = ActiveSupport::MessageEncryptor.new(secret, cipher: "aes-256-gcm", serializer: Marshal)
+
+    assert_equal "bar", encryptor.decrypt_and_verify(@response.cookies["foo"])
+  end
+
+  def test_encrypted_cookie_rotating_secret
+    secret = "b3c631c314c0bbca50c1b2843150fe33"
+
+    @request.env["action_dispatch.encrypted_cookie_cipher"] = "aes-256-gcm"
+    @request.env["action_dispatch.cookies_rotations"].rotate :encrypted, secret
+
+    key_len = ActiveSupport::MessageEncryptor.key_len("aes-256-gcm")
+
+    old_message = ActiveSupport::MessageEncryptor.new(secret, cipher: "aes-256-gcm", serializer: Marshal).encrypt_and_sign(45)
+
+    @request.headers["Cookie"] = "foo=#{::Rack::Utils.escape old_message}"
+
+    get :get_encrypted_cookie
+    assert_equal 45, @controller.send(:cookies).encrypted[:foo]
+
+    key_generator = @request.env["action_dispatch.key_generator"]
+    secret = key_generator.generate_key(@request.env["action_dispatch.authenticated_encrypted_cookie_salt"], key_len)
+    encryptor = ActiveSupport::MessageEncryptor.new(secret, cipher: "aes-256-gcm", serializer: Marshal)
+    assert_equal 45, encryptor.decrypt_and_verify(@response.cookies["foo"])
   end
 
   def test_cookie_with_all_domain_option
@@ -998,7 +1083,7 @@ class CookiesTest < ActionController::TestCase
   end
 
   def test_deleting_cookie_with_all_domain_option
-    request.cookies[:user_name] = 'Joe'
+    request.cookies[:user_name] = "Joe"
     get :delete_cookie_with_domain
     assert_response :success
     assert_cookie_header "user_name=; domain=.nextangle.com; path=/; max-age=0; expires=Thu, 01 Jan 1970 00:00:00 -0000"
@@ -1032,7 +1117,7 @@ class CookiesTest < ActionController::TestCase
   end
 
   def test_deleting_cookie_with_all_domain_option_and_tld_length
-    request.cookies[:user_name] = 'Joe'
+    request.cookies[:user_name] = "Joe"
     get :delete_cookie_with_domain_and_tld
     assert_response :success
     assert_cookie_header "user_name=; domain=.nextangle.com; path=/; max-age=0; expires=Thu, 01 Jan 1970 00:00:00 -0000"
@@ -1061,7 +1146,7 @@ class CookiesTest < ActionController::TestCase
 
   def test_deletings_cookie_with_several_preset_domains_using_one_of_these_domains
     @request.host = "example2.com"
-    request.cookies[:user_name] = 'Joe'
+    request.cookies[:user_name] = "Joe"
     get :delete_cookie_with_domains
     assert_response :success
     assert_cookie_header "user_name=; domain=example2.com; path=/; max-age=0; expires=Thu, 01 Jan 1970 00:00:00 -0000"
@@ -1069,7 +1154,7 @@ class CookiesTest < ActionController::TestCase
 
   def test_deletings_cookie_with_several_preset_domains_using_other_domain
     @request.host = "other-domain.com"
-    request.cookies[:user_name] = 'Joe'
+    request.cookies[:user_name] = "Joe"
     get :delete_cookie_with_domains
     assert_response :success
     assert_cookie_header "user_name=; path=/; max-age=0; expires=Thu, 01 Jan 1970 00:00:00 -0000"
@@ -1078,20 +1163,20 @@ class CookiesTest < ActionController::TestCase
   def test_cookies_hash_is_indifferent_access
     get :symbol_key
     assert_equal "david", cookies[:user_name]
-    assert_equal "david", cookies['user_name']
+    assert_equal "david", cookies["user_name"]
     get :string_key
     assert_equal "dhh", cookies[:user_name]
-    assert_equal "dhh", cookies['user_name']
+    assert_equal "dhh", cookies["user_name"]
   end
 
   def test_setting_request_cookies_is_indifferent_access
     cookies.clear
     cookies[:user_name] = "andrew"
     get :string_key_mock
-    assert_equal "david", cookies['user_name']
+    assert_equal "david", cookies["user_name"]
 
     cookies.clear
-    cookies['user_name'] = "andrew"
+    cookies["user_name"] = "andrew"
     get :symbol_key_mock
     assert_equal "david", cookies[:user_name]
   end
@@ -1102,11 +1187,11 @@ class CookiesTest < ActionController::TestCase
     assert_equal "david", cookies[:user_name]
 
     get :noop
-    assert !@response.headers.include?("Set-Cookie")
+    assert_not_includes @response.headers, "Set-Cookie"
     assert_equal "david", cookies[:user_name]
 
     get :noop
-    assert !@response.headers.include?("Set-Cookie")
+    assert_not_includes @response.headers, "Set-Cookie"
     assert_equal "david", cookies[:user_name]
   end
 
@@ -1123,57 +1208,90 @@ class CookiesTest < ActionController::TestCase
   end
 
   def test_can_set_http_cookie_header
-    @request.env['HTTP_COOKIE'] = 'user_name=david'
+    @request.env["HTTP_COOKIE"] = "user_name=david"
     get :noop
-    assert_equal 'david', cookies['user_name']
-    assert_equal 'david', cookies[:user_name]
+    assert_equal "david", cookies["user_name"]
+    assert_equal "david", cookies[:user_name]
 
     get :noop
-    assert_equal 'david', cookies['user_name']
-    assert_equal 'david', cookies[:user_name]
+    assert_equal "david", cookies["user_name"]
+    assert_equal "david", cookies[:user_name]
 
-    @request.env['HTTP_COOKIE'] = 'user_name=andrew'
+    @request.env["HTTP_COOKIE"] = "user_name=andrew"
     get :noop
-    assert_equal 'andrew', cookies['user_name']
-    assert_equal 'andrew', cookies[:user_name]
+    assert_equal "andrew", cookies["user_name"]
+    assert_equal "andrew", cookies[:user_name]
   end
 
   def test_can_set_request_cookies
-    @request.cookies['user_name'] = 'david'
+    @request.cookies["user_name"] = "david"
     get :noop
-    assert_equal 'david', cookies['user_name']
-    assert_equal 'david', cookies[:user_name]
+    assert_equal "david", cookies["user_name"]
+    assert_equal "david", cookies[:user_name]
 
     get :noop
-    assert_equal 'david', cookies['user_name']
-    assert_equal 'david', cookies[:user_name]
+    assert_equal "david", cookies["user_name"]
+    assert_equal "david", cookies[:user_name]
 
-    @request.cookies[:user_name] = 'andrew'
+    @request.cookies[:user_name] = "andrew"
     get :noop
-    assert_equal 'andrew', cookies['user_name']
-    assert_equal 'andrew', cookies[:user_name]
+    assert_equal "andrew", cookies["user_name"]
+    assert_equal "andrew", cookies[:user_name]
   end
 
   def test_cookies_precedence_over_http_cookie
-    @request.env['HTTP_COOKIE'] = 'user_name=andrew'
+    @request.env["HTTP_COOKIE"] = "user_name=andrew"
     get :authenticate
-    assert_equal 'david', cookies['user_name']
-    assert_equal 'david', cookies[:user_name]
+    assert_equal "david", cookies["user_name"]
+    assert_equal "david", cookies[:user_name]
 
     get :noop
-    assert_equal 'david', cookies['user_name']
-    assert_equal 'david', cookies[:user_name]
+    assert_equal "david", cookies["user_name"]
+    assert_equal "david", cookies[:user_name]
   end
 
   def test_cookies_precedence_over_request_cookies
-    @request.cookies['user_name'] = 'andrew'
+    @request.cookies["user_name"] = "andrew"
     get :authenticate
-    assert_equal 'david', cookies['user_name']
-    assert_equal 'david', cookies[:user_name]
+    assert_equal "david", cookies["user_name"]
+    assert_equal "david", cookies[:user_name]
 
     get :noop
-    assert_equal 'david', cookies['user_name']
-    assert_equal 'david', cookies[:user_name]
+    assert_equal "david", cookies["user_name"]
+    assert_equal "david", cookies[:user_name]
+  end
+
+  def test_cookies_are_not_cleared
+    cookies.encrypted["foo"] = "bar"
+    get :noop
+    assert_equal "bar", @controller.encrypted_cookie
+  end
+
+  def test_signed_cookie_with_expires_set_relatively
+    cookies.signed[:user_name] = { value: "assain", expires: 2.hours }
+
+    travel 1.hour
+    assert_equal "assain", cookies.signed[:user_name]
+
+    travel 2.hours
+    assert_nil cookies.signed[:user_name]
+  end
+
+  def test_encrypted_cookie_with_expires_set_relatively
+    cookies.encrypted[:user_name] = { value: "assain", expires: 2.hours }
+
+    travel 1.hour
+    assert_equal "assain", cookies.encrypted[:user_name]
+
+    travel 2.hours
+    assert_nil cookies.encrypted[:user_name]
+  end
+
+  def test_vanilla_cookie_with_expires_set_relatively
+    travel_to Time.utc(2017, 8, 15) do
+      get :cookie_expires_in_two_hours
+      assert_cookie_header "user_name=assain; path=/; expires=Tue, 15 Aug 2017 02:00:00 -0000"
+    end
   end
 
   private
diff --git a/actionpack/test/dispatch/debug_exceptions_test.rb b/actionpack/test/dispatch/debug_exceptions_test.rb
index 5a39db145e..60acba0616 100644
--- a/actionpack/test/dispatch/debug_exceptions_test.rb
+++ b/actionpack/test/dispatch/debug_exceptions_test.rb
@@ -1,7 +1,8 @@
-require 'abstract_unit'
+# frozen_string_literal: true
 
-class DebugExceptionsTest < ActionDispatch::IntegrationTest
+require "abstract_unit"
 
+class DebugExceptionsTest < ActionDispatch::IntegrationTest
   class Boomer
     attr_accessor :closed
 
@@ -20,11 +21,11 @@ class DebugExceptionsTest < ActionDispatch::IntegrationTest
     end
 
     def method_that_raises
-      raise StandardError.new 'error in framework'
+      raise StandardError.new "error in framework"
     end
 
     def call(env)
-      env['action_dispatch.show_detailed_exceptions'] = @detailed
+      env["action_dispatch.show_detailed_exceptions"] = @detailed
       req = ActionDispatch::Request.new(env)
       case req.path
       when %r{/pass}
@@ -45,10 +46,10 @@ class DebugExceptionsTest < ActionDispatch::IntegrationTest
         begin
           raise AbstractController::ActionNotFound.new
         rescue
-          raise ActionView::Template::Error.new('template')
+          raise ActionView::Template::Error.new("template")
         end
       when %r{/missing_template}
-        raise ActionView::MissingTemplate.new(%w(foo), 'foo/index', %w(foo), false, 'mailer')
+        raise ActionView::MissingTemplate.new(%w(foo), "foo/index", %w(foo), false, "mailer")
       when %r{/bad_request}
         raise ActionController::BadRequest
       when %r{/missing_keys}
@@ -56,10 +57,10 @@ class DebugExceptionsTest < ActionDispatch::IntegrationTest
       when %r{/parameter_missing}
         raise ActionController::ParameterMissing, :missing_param_key
       when %r{/original_syntax_error}
-        eval 'broke_syntax =' # `eval` need for raise native SyntaxError at runtime
+        eval "broke_syntax =" # `eval` need for raise native SyntaxError at runtime
       when %r{/syntax_error_into_view}
         begin
-          eval 'broke_syntax ='
+          eval "broke_syntax ="
         rescue Exception
           template = ActionView::Template.new(File.read(__FILE__),
                                               __FILE__,
@@ -79,85 +80,85 @@ class DebugExceptionsTest < ActionDispatch::IntegrationTest
   ProductionApp  = ActionDispatch::DebugExceptions.new(Boomer.new(false), RoutesApp)
   DevelopmentApp = ActionDispatch::DebugExceptions.new(Boomer.new(true), RoutesApp)
 
-  test 'skip diagnosis if not showing detailed exceptions' do
+  test "skip diagnosis if not showing detailed exceptions" do
     @app = ProductionApp
     assert_raise RuntimeError do
-      get "/", headers: { 'action_dispatch.show_exceptions' => true }
+      get "/", headers: { "action_dispatch.show_exceptions" => true }
     end
   end
 
-  test 'skip diagnosis if not showing exceptions' do
+  test "skip diagnosis if not showing exceptions" do
     @app = DevelopmentApp
     assert_raise RuntimeError do
-      get "/", headers: { 'action_dispatch.show_exceptions' => false }
+      get "/", headers: { "action_dispatch.show_exceptions" => false }
     end
   end
 
-  test 'raise an exception on cascade pass' do
+  test "raise an exception on cascade pass" do
     @app = ProductionApp
     assert_raise ActionController::RoutingError do
-      get "/pass", headers: { 'action_dispatch.show_exceptions' => true }
+      get "/pass", headers: { "action_dispatch.show_exceptions" => true }
     end
   end
 
-  test 'closes the response body on cascade pass' do
+  test "closes the response body on cascade pass" do
     boomer = Boomer.new(false)
     @app = ActionDispatch::DebugExceptions.new(boomer)
     assert_raise ActionController::RoutingError do
-      get "/pass", headers: { 'action_dispatch.show_exceptions' => true }
+      get "/pass", headers: { "action_dispatch.show_exceptions" => true }
     end
     assert boomer.closed, "Expected to close the response body"
   end
 
-  test 'displays routes in a table when a RoutingError occurs' do
+  test "displays routes in a table when a RoutingError occurs" do
     @app = DevelopmentApp
-    get "/pass", headers: { 'action_dispatch.show_exceptions' => true }
+    get "/pass", headers: { "action_dispatch.show_exceptions" => true }
     routing_table = body[/route_table.*<.table>/m]
-    assert_match '/:controller(/:action)(.:format)', routing_table
-    assert_match ':controller#:action', routing_table
-    assert_no_match '&lt;|&gt;', routing_table, "there should not be escaped html in the output"
+    assert_match "/:controller(/:action)(.:format)", routing_table
+    assert_match ":controller#:action", routing_table
+    assert_no_match "&lt;|&gt;", routing_table, "there should not be escaped html in the output"
   end
 
-  test 'displays request and response info when a RoutingError occurs' do
+  test "displays request and response info when a RoutingError occurs" do
     @app = DevelopmentApp
 
-    get "/pass", headers: { 'action_dispatch.show_exceptions' => true }
+    get "/pass", headers: { "action_dispatch.show_exceptions" => true }
 
-    assert_select 'h2', /Request/
-    assert_select 'h2', /Response/
+    assert_select "h2", /Request/
+    assert_select "h2", /Response/
   end
 
   test "rescue with diagnostics message" do
     @app = DevelopmentApp
 
-    get "/", headers: { 'action_dispatch.show_exceptions' => true }
+    get "/", headers: { "action_dispatch.show_exceptions" => true }
     assert_response 500
     assert_match(/puke/, body)
 
-    get "/not_found", headers: { 'action_dispatch.show_exceptions' => true }
+    get "/not_found", headers: { "action_dispatch.show_exceptions" => true }
     assert_response 404
     assert_match(/#{AbstractController::ActionNotFound.name}/, body)
 
-    get "/method_not_allowed", headers: { 'action_dispatch.show_exceptions' => true }
+    get "/method_not_allowed", headers: { "action_dispatch.show_exceptions" => true }
     assert_response 405
     assert_match(/ActionController::MethodNotAllowed/, body)
 
-    get "/unknown_http_method", headers: { 'action_dispatch.show_exceptions' => true }
+    get "/unknown_http_method", headers: { "action_dispatch.show_exceptions" => true }
     assert_response 405
     assert_match(/ActionController::UnknownHttpMethod/, body)
 
-    get "/bad_request", headers: { 'action_dispatch.show_exceptions' => true }
+    get "/bad_request", headers: { "action_dispatch.show_exceptions" => true }
     assert_response 400
     assert_match(/ActionController::BadRequest/, body)
 
-    get "/parameter_missing", headers: { 'action_dispatch.show_exceptions' => true }
+    get "/parameter_missing", headers: { "action_dispatch.show_exceptions" => true }
     assert_response 400
     assert_match(/ActionController::ParameterMissing/, body)
   end
 
   test "rescue with text error for xhr request" do
     @app = DevelopmentApp
-    xhr_request_env = {'action_dispatch.show_exceptions' => true, 'HTTP_X_REQUESTED_WITH' => 'XMLHttpRequest'}
+    xhr_request_env = { "action_dispatch.show_exceptions" => true, "HTTP_X_REQUESTED_WITH" => "XMLHttpRequest" }
 
     get "/", headers: xhr_request_env
     assert_response 500
@@ -166,12 +167,12 @@ class DebugExceptionsTest < ActionDispatch::IntegrationTest
     assert_equal "text/plain", response.content_type
     assert_match(/RuntimeError\npuke/, body)
 
-    Rails.stub :root, Pathname.new('.') do
+    Rails.stub :root, Pathname.new(".") do
       get "/", headers: xhr_request_env
 
       assert_response 500
-      assert_match 'Extracted source (around line #', body
-      assert_select 'pre', { count: 0 }, body
+      assert_match "Extracted source (around line #", body
+      assert_select "pre", { count: 0 }, body
     end
 
     get "/not_found", headers: xhr_request_env
@@ -208,38 +209,38 @@ class DebugExceptionsTest < ActionDispatch::IntegrationTest
   test "rescue with JSON error for JSON API request" do
     @app = ActionDispatch::DebugExceptions.new(Boomer.new(true), RoutesApp, :api)
 
-    get "/", headers: { 'action_dispatch.show_exceptions' => true }, as: :json
+    get "/", headers: { "action_dispatch.show_exceptions" => true }, as: :json
     assert_response 500
     assert_no_match(/<header>/, body)
     assert_no_match(/<body>/, body)
     assert_equal "application/json", response.content_type
     assert_match(/RuntimeError: puke/, body)
 
-    get "/not_found", headers: { 'action_dispatch.show_exceptions' => true }, as: :json
+    get "/not_found", headers: { "action_dispatch.show_exceptions" => true }, as: :json
     assert_response 404
     assert_no_match(/<body>/, body)
     assert_equal "application/json", response.content_type
     assert_match(/#{AbstractController::ActionNotFound.name}/, body)
 
-    get "/method_not_allowed", headers: { 'action_dispatch.show_exceptions' => true }, as: :json
+    get "/method_not_allowed", headers: { "action_dispatch.show_exceptions" => true }, as: :json
     assert_response 405
     assert_no_match(/<body>/, body)
     assert_equal "application/json", response.content_type
     assert_match(/ActionController::MethodNotAllowed/, body)
 
-    get "/unknown_http_method", headers: { 'action_dispatch.show_exceptions' => true }, as: :json
+    get "/unknown_http_method", headers: { "action_dispatch.show_exceptions" => true }, as: :json
     assert_response 405
     assert_no_match(/<body>/, body)
     assert_equal "application/json", response.content_type
     assert_match(/ActionController::UnknownHttpMethod/, body)
 
-    get "/bad_request", headers: { 'action_dispatch.show_exceptions' => true }, as: :json
+    get "/bad_request", headers: { "action_dispatch.show_exceptions" => true }, as: :json
     assert_response 400
     assert_no_match(/<body>/, body)
     assert_equal "application/json", response.content_type
     assert_match(/ActionController::BadRequest/, body)
 
-    get "/parameter_missing", headers: { 'action_dispatch.show_exceptions' => true }, as: :json
+    get "/parameter_missing", headers: { "action_dispatch.show_exceptions" => true }, as: :json
     assert_response 400
     assert_no_match(/<body>/, body)
     assert_equal "application/json", response.content_type
@@ -249,7 +250,7 @@ class DebugExceptionsTest < ActionDispatch::IntegrationTest
   test "rescue with HTML format for HTML API request" do
     @app = ActionDispatch::DebugExceptions.new(Boomer.new(true), RoutesApp, :api)
 
-    get "/index.html", headers: { 'action_dispatch.show_exceptions' => true }
+    get "/index.html", headers: { "action_dispatch.show_exceptions" => true }
     assert_response 500
     assert_match(/<header>/, body)
     assert_match(/<body>/, body)
@@ -260,7 +261,7 @@ class DebugExceptionsTest < ActionDispatch::IntegrationTest
   test "rescue with XML format for XML API requests" do
     @app = ActionDispatch::DebugExceptions.new(Boomer.new(true), RoutesApp, :api)
 
-    get "/index.xml", headers: { 'action_dispatch.show_exceptions' => true }
+    get "/index.xml", headers: { "action_dispatch.show_exceptions" => true }
     assert_response 500
     assert_equal "application/xml", response.content_type
     assert_match(/RuntimeError: puke/, body)
@@ -268,14 +269,14 @@ class DebugExceptionsTest < ActionDispatch::IntegrationTest
 
   test "rescue with JSON format as fallback if API request format is not supported" do
     begin
-      Mime::Type.register 'text/wibble', :wibble
+      Mime::Type.register "text/wibble", :wibble
 
       ActionDispatch::IntegrationTest.register_encoder(:wibble,
         param_encoder: -> params { params })
 
       @app = ActionDispatch::DebugExceptions.new(Boomer.new(true), RoutesApp, :api)
 
-      get "/index", headers: { 'action_dispatch.show_exceptions' => true }, as: :wibble
+      get "/index", headers: { "action_dispatch.show_exceptions" => true }, as: :wibble
       assert_response 500
       assert_equal "application/json", response.content_type
       assert_match(/RuntimeError: puke/, body)
@@ -288,8 +289,8 @@ class DebugExceptionsTest < ActionDispatch::IntegrationTest
   test "does not show filtered parameters" do
     @app = DevelopmentApp
 
-    get "/", params: { "foo"=>"bar" }, headers: { 'action_dispatch.show_exceptions' => true,
-      'action_dispatch.parameter_filter' => [:foo] }
+    get "/", params: { "foo" => "bar" }, headers: { "action_dispatch.show_exceptions" => true,
+      "action_dispatch.parameter_filter" => [:foo] }
     assert_response 500
     assert_match("&quot;foo&quot;=&gt;&quot;[FILTERED]&quot;", body)
   end
@@ -297,7 +298,7 @@ class DebugExceptionsTest < ActionDispatch::IntegrationTest
   test "show registered original exception for wrapped exceptions" do
     @app = DevelopmentApp
 
-    get "/not_found_original_exception", headers: { 'action_dispatch.show_exceptions' => true }
+    get "/not_found_original_exception", headers: { "action_dispatch.show_exceptions" => true }
     assert_response 404
     assert_match(/AbstractController::ActionNotFound/, body)
   end
@@ -305,7 +306,7 @@ class DebugExceptionsTest < ActionDispatch::IntegrationTest
   test "named urls missing keys raise 500 level error" do
     @app = DevelopmentApp
 
-    get "/missing_keys", headers: { 'action_dispatch.show_exceptions' => true }
+    get "/missing_keys", headers: { "action_dispatch.show_exceptions" => true }
     assert_response 500
 
     assert_match(/ActionController::UrlGenerationError/, body)
@@ -314,11 +315,11 @@ class DebugExceptionsTest < ActionDispatch::IntegrationTest
   test "show the controller name in the diagnostics template when controller name is present" do
     @app = DevelopmentApp
     get("/runtime_error", headers: {
-      'action_dispatch.show_exceptions' => true,
-      'action_dispatch.request.parameters' => {
-        'action' => 'show',
-        'id' => 'unknown',
-        'controller' => 'featured_tile'
+      "action_dispatch.show_exceptions" => true,
+      "action_dispatch.request.parameters" => {
+        "action" => "show",
+        "id" => "unknown",
+        "controller" => "featured_tile"
       }
     })
     assert_response 500
@@ -329,74 +330,114 @@ class DebugExceptionsTest < ActionDispatch::IntegrationTest
     @app = DevelopmentApp
 
     params = {
-      'id' => 'unknown',
-      'someparam' => {
-        'foo' => 'bar',
-        'abc' => 'goo'
+      "id" => "unknown",
+      "someparam" => {
+        "foo" => "bar",
+        "abc" => "goo"
       }
     }
 
     get("/runtime_error", headers: {
-      'action_dispatch.show_exceptions' => true,
-      'action_dispatch.request.parameters' => {
-        'action' => 'show',
-        'controller' => 'featured_tile'
+      "action_dispatch.show_exceptions" => true,
+      "action_dispatch.request.parameters" => {
+        "action" => "show",
+        "controller" => "featured_tile"
       }.merge(params)
     })
     assert_response 500
 
-    assert_includes(body, CGI.escapeHTML(PP.pp(params, "", 200)))
+    assert_includes(body, CGI.escapeHTML(PP.pp(params, "".dup, 200)))
   end
 
   test "sets the HTTP charset parameter" do
     @app = DevelopmentApp
 
-    get "/", headers: { 'action_dispatch.show_exceptions' => true }
+    get "/", headers: { "action_dispatch.show_exceptions" => true }
     assert_equal "text/html; charset=utf-8", response.headers["Content-Type"]
   end
 
-  test 'uses logger from env' do
+  test "uses logger from env" do
     @app = DevelopmentApp
     output = StringIO.new
-    get "/", headers: { 'action_dispatch.show_exceptions' => true, 'action_dispatch.logger' => Logger.new(output) }
+    get "/", headers: { "action_dispatch.show_exceptions" => true, "action_dispatch.logger" => Logger.new(output) }
     assert_match(/puke/, output.rewind && output.read)
   end
 
-  test 'uses backtrace cleaner from env' do
+  test "logs only what is necessary" do
+    @app = DevelopmentApp
+    io = StringIO.new
+    logger = ActiveSupport::Logger.new(io)
+
+    _old, ActionView::Base.logger = ActionView::Base.logger, logger
+    begin
+      get "/", headers: { "action_dispatch.show_exceptions" => true, "action_dispatch.logger" => logger }
+    ensure
+      ActionView::Base.logger = _old
+    end
+
+    output = io.rewind && io.read
+    lines = output.lines
+
+    # Other than the first three...
+    assert_equal(["  \n", "RuntimeError (puke!):\n", "  \n"], lines.slice!(0, 3))
+    lines.each do |line|
+      # .. all the remaining lines should be from the backtrace
+      assert_match(/:\d+:in /, line)
+    end
+  end
+
+  test "logs with non active support loggers" do
+    @app = DevelopmentApp
+    io = StringIO.new
+    logger = Logger.new(io)
+
+    _old, ActionView::Base.logger = ActionView::Base.logger, logger
+    begin
+      assert_nothing_raised do
+        get "/", headers: { "action_dispatch.show_exceptions" => true, "action_dispatch.logger" => logger }
+      end
+    ensure
+      ActionView::Base.logger = _old
+    end
+
+    assert_match(/puke/, io.rewind && io.read)
+  end
+
+  test "uses backtrace cleaner from env" do
     @app = DevelopmentApp
     backtrace_cleaner = ActiveSupport::BacktraceCleaner.new
 
-    backtrace_cleaner.stub :clean, ['passed backtrace cleaner'] do
-      get "/", headers: { 'action_dispatch.show_exceptions' => true, 'action_dispatch.backtrace_cleaner' => backtrace_cleaner }
+    backtrace_cleaner.stub :clean, ["passed backtrace cleaner"] do
+      get "/", headers: { "action_dispatch.show_exceptions" => true, "action_dispatch.backtrace_cleaner" => backtrace_cleaner }
       assert_match(/passed backtrace cleaner/, body)
     end
   end
 
-  test 'logs exception backtrace when all lines silenced' do
+  test "logs exception backtrace when all lines silenced" do
     output = StringIO.new
     backtrace_cleaner = ActiveSupport::BacktraceCleaner.new
     backtrace_cleaner.add_silencer { true }
 
-    env = {'action_dispatch.show_exceptions' => true,
-           'action_dispatch.logger' => Logger.new(output),
-           'action_dispatch.backtrace_cleaner' => backtrace_cleaner}
+    env = { "action_dispatch.show_exceptions" => true,
+           "action_dispatch.logger" => Logger.new(output),
+           "action_dispatch.backtrace_cleaner" => backtrace_cleaner }
 
     get "/", headers: env
     assert_operator((output.rewind && output.read).lines.count, :>, 10)
   end
 
-  test 'display backtrace when error type is SyntaxError' do
+  test "display backtrace when error type is SyntaxError" do
     @app = DevelopmentApp
 
-    get '/original_syntax_error', headers: { 'action_dispatch.backtrace_cleaner' => ActiveSupport::BacktraceCleaner.new }
+    get "/original_syntax_error", headers: { "action_dispatch.backtrace_cleaner" => ActiveSupport::BacktraceCleaner.new }
 
     assert_response 500
-    assert_select '#Application-Trace' do
-      assert_select 'pre code', /syntax error, unexpected/
+    assert_select "#Application-Trace" do
+      assert_select "pre code", /syntax error, unexpected/
     end
   end
 
-  test 'display backtrace on template missing errors' do
+  test "display backtrace on template missing errors" do
     @app = DevelopmentApp
 
     get "/missing_template"
@@ -405,56 +446,56 @@ class DebugExceptionsTest < ActionDispatch::IntegrationTest
 
     assert_select "#container h2", /^Missing template/
 
-    assert_select '#Application-Trace'
-    assert_select '#Framework-Trace'
-    assert_select '#Full-Trace'
+    assert_select "#Application-Trace"
+    assert_select "#Framework-Trace"
+    assert_select "#Full-Trace"
 
-    assert_select 'h2', /Request/
+    assert_select "h2", /Request/
   end
 
-  test 'display backtrace when error type is SyntaxError wrapped by ActionView::Template::Error' do
+  test "display backtrace when error type is SyntaxError wrapped by ActionView::Template::Error" do
     @app = DevelopmentApp
 
-    get '/syntax_error_into_view', headers: { 'action_dispatch.backtrace_cleaner' => ActiveSupport::BacktraceCleaner.new }
+    get "/syntax_error_into_view", headers: { "action_dispatch.backtrace_cleaner" => ActiveSupport::BacktraceCleaner.new }
 
     assert_response 500
-    assert_select '#Application-Trace' do
-      assert_select 'pre code', /syntax error, unexpected/
+    assert_select "#Application-Trace" do
+      assert_select "pre code", /syntax error, unexpected/
     end
   end
 
-  test 'debug exceptions app shows user code that caused the error in source view' do
+  test "debug exceptions app shows user code that caused the error in source view" do
     @app = DevelopmentApp
-    Rails.stub :root, Pathname.new('.') do
+    Rails.stub :root, Pathname.new(".") do
       cleaner = ActiveSupport::BacktraceCleaner.new.tap do |bc|
         bc.add_silencer { |line| line =~ /method_that_raises/ }
         bc.add_silencer { |line| line !~ %r{test/dispatch/debug_exceptions_test.rb} }
       end
 
-      get '/framework_raises', headers: { 'action_dispatch.backtrace_cleaner' => cleaner }
+      get "/framework_raises", headers: { "action_dispatch.backtrace_cleaner" => cleaner }
 
       # Assert correct error
       assert_response 500
-      assert_select 'h2', /error in framework/
+      assert_select "h2", /error in framework/
 
       # assert source view line is the call to method_that_raises
-      assert_select 'div.source:not(.hidden)' do
-        assert_select 'pre .line.active', /method_that_raises/
+      assert_select "div.source:not(.hidden)" do
+        assert_select "pre .line.active", /method_that_raises/
       end
 
       # assert first source view (hidden) that throws the error
-      assert_select 'div.source:first' do
-        assert_select 'pre .line.active', /raise StandardError\.new/
+      assert_select "div.source:first" do
+        assert_select "pre .line.active", /raise StandardError\.new/
       end
 
       # assert application trace refers to line that calls method_that_raises is first
-      assert_select '#Application-Trace' do
-        assert_select 'pre code a:first', %r{test/dispatch/debug_exceptions_test\.rb:\d+:in `call}
+      assert_select "#Application-Trace" do
+        assert_select "pre code a:first", %r{test/dispatch/debug_exceptions_test\.rb:\d+:in `call}
       end
 
       # assert framework trace that threw the error is first
-      assert_select '#Framework-Trace' do
-        assert_select 'pre code a:first', /method_that_raises/
+      assert_select "#Framework-Trace" do
+        assert_select "pre code a:first", /method_that_raises/
       end
     end
   end
diff --git a/actionpack/test/dispatch/debug_locks_test.rb b/actionpack/test/dispatch/debug_locks_test.rb
new file mode 100644
index 0000000000..d69614bd79
--- /dev/null
+++ b/actionpack/test/dispatch/debug_locks_test.rb
@@ -0,0 +1,38 @@
+# frozen_string_literal: true
+
+require "abstract_unit"
+
+class DebugLocksTest < ActionDispatch::IntegrationTest
+  setup do
+    build_app
+  end
+
+  def test_render_threads_status
+    thread_ready = Concurrent::CountDownLatch.new
+    test_terminated = Concurrent::CountDownLatch.new
+
+    thread = Thread.new do
+      ActiveSupport::Dependencies.interlock.running do
+        thread_ready.count_down
+        test_terminated.wait
+      end
+    end
+
+    thread_ready.wait
+
+    get "/rails/locks"
+
+    test_terminated.count_down
+
+    assert_match(/Thread.*?Sharing/, @response.body)
+  ensure
+    thread.join
+  end
+
+  private
+    def build_app
+      @app = self.class.build_app do |middleware|
+        middleware.use ActionDispatch::DebugLocks
+      end
+    end
+end
diff --git a/actionpack/test/dispatch/exception_wrapper_test.rb b/actionpack/test/dispatch/exception_wrapper_test.rb
index dfbb91c0ca..f6e70382a8 100644
--- a/actionpack/test/dispatch/exception_wrapper_test.rb
+++ b/actionpack/test/dispatch/exception_wrapper_test.rb
@@ -1,4 +1,6 @@
-require 'abstract_unit'
+# frozen_string_literal: true
+
+require "abstract_unit"
 
 module ActionDispatch
   class ExceptionWrapperTest < ActionDispatch::IntegrationTest
@@ -21,43 +23,49 @@ module ActionDispatch
       @cleaner.add_silencer { |line| line !~ /^lib/ }
     end
 
-    test '#source_extracts fetches source fragments for every backtrace entry' do
+    test "#source_extracts fetches source fragments for every backtrace entry" do
       exception = TestError.new("lib/file.rb:42:in `index'")
       wrapper = ExceptionWrapper.new(nil, exception)
 
-      assert_called_with(wrapper, :source_fragment, ['lib/file.rb', 42], returns: 'foo') do
-        assert_equal [ code: 'foo', line_number: 42 ], wrapper.source_extracts
+      assert_called_with(wrapper, :source_fragment, ["lib/file.rb", 42], returns: "foo") do
+        assert_equal [ code: "foo", line_number: 42 ], wrapper.source_extracts
       end
     end
 
-    test '#source_extracts works with Windows paths' do
+    test "#source_extracts works with Windows paths" do
       exc = TestError.new("c:/path/to/rails/app/controller.rb:27:in 'index':")
 
       wrapper = ExceptionWrapper.new(nil, exc)
 
-      assert_called_with(wrapper, :source_fragment, ['c:/path/to/rails/app/controller.rb', 27], returns: 'nothing') do
-        assert_equal [ code: 'nothing', line_number: 27 ], wrapper.source_extracts
+      assert_called_with(wrapper, :source_fragment, ["c:/path/to/rails/app/controller.rb", 27], returns: "nothing") do
+        assert_equal [ code: "nothing", line_number: 27 ], wrapper.source_extracts
       end
     end
 
-    test '#source_extracts works with non standard backtrace' do
-      exc = TestError.new('invalid')
+    test "#source_extracts works with non standard backtrace" do
+      exc = TestError.new("invalid")
 
       wrapper = ExceptionWrapper.new(nil, exc)
 
-      assert_called_with(wrapper, :source_fragment, ['invalid', 0], returns: 'nothing') do
-        assert_equal [ code: 'nothing', line_number: 0 ], wrapper.source_extracts
+      assert_called_with(wrapper, :source_fragment, ["invalid", 0], returns: "nothing") do
+        assert_equal [ code: "nothing", line_number: 0 ], wrapper.source_extracts
       end
     end
 
-    test '#application_trace returns traces only from the application' do
+    test "#application_trace returns traces only from the application" do
       exception = TestError.new(caller.prepend("lib/file.rb:42:in `index'"))
       wrapper = ExceptionWrapper.new(@cleaner, exception)
 
       assert_equal [ "lib/file.rb:42:in `index'" ], wrapper.application_trace
     end
 
-    test '#application_trace cannot be nil' do
+    test "#status_code returns 400 for Rack::Utils::ParameterTypeError" do
+      exception = Rack::Utils::ParameterTypeError.new
+      wrapper = ExceptionWrapper.new(@cleaner, exception)
+      assert_equal 400, wrapper.status_code
+    end
+
+    test "#application_trace cannot be nil" do
       nil_backtrace_wrapper = ExceptionWrapper.new(@cleaner, BadlyDefinedError.new)
       nil_cleaner_wrapper = ExceptionWrapper.new(nil, BadlyDefinedError.new)
 
@@ -65,14 +73,14 @@ module ActionDispatch
       assert_equal [], nil_cleaner_wrapper.application_trace
     end
 
-    test '#framework_trace returns traces outside the application' do
+    test "#framework_trace returns traces outside the application" do
       exception = TestError.new(caller.prepend("lib/file.rb:42:in `index'"))
       wrapper = ExceptionWrapper.new(@cleaner, exception)
 
       assert_equal caller, wrapper.framework_trace
     end
 
-    test '#framework_trace cannot be nil' do
+    test "#framework_trace cannot be nil" do
       nil_backtrace_wrapper = ExceptionWrapper.new(@cleaner, BadlyDefinedError.new)
       nil_cleaner_wrapper = ExceptionWrapper.new(nil, BadlyDefinedError.new)
 
@@ -80,14 +88,14 @@ module ActionDispatch
       assert_equal [], nil_cleaner_wrapper.framework_trace
     end
 
-    test '#full_trace returns application and framework traces' do
+    test "#full_trace returns application and framework traces" do
       exception = TestError.new(caller.prepend("lib/file.rb:42:in `index'"))
       wrapper = ExceptionWrapper.new(@cleaner, exception)
 
       assert_equal exception.backtrace, wrapper.full_trace
     end
 
-    test '#full_trace cannot be nil' do
+    test "#full_trace cannot be nil" do
       nil_backtrace_wrapper = ExceptionWrapper.new(@cleaner, BadlyDefinedError.new)
       nil_cleaner_wrapper = ExceptionWrapper.new(nil, BadlyDefinedError.new)
 
@@ -95,14 +103,14 @@ module ActionDispatch
       assert_equal [], nil_cleaner_wrapper.full_trace
     end
 
-    test '#traces returns every trace by category enumerated with an index' do
+    test "#traces returns every trace by category enumerated with an index" do
       exception = TestError.new("lib/file.rb:42:in `index'", "/gems/rack.rb:43:in `index'")
       wrapper = ExceptionWrapper.new(@cleaner, exception)
 
       assert_equal({
-        'Application Trace' => [ id: 0, trace: "lib/file.rb:42:in `index'" ],
-        'Framework Trace' => [ id: 1, trace: "/gems/rack.rb:43:in `index'" ],
-        'Full Trace' => [
+        "Application Trace" => [ id: 0, trace: "lib/file.rb:42:in `index'" ],
+        "Framework Trace" => [ id: 1, trace: "/gems/rack.rb:43:in `index'" ],
+        "Full Trace" => [
           { id: 0, trace: "lib/file.rb:42:in `index'" },
           { id: 1, trace: "/gems/rack.rb:43:in `index'" }
         ]
diff --git a/actionpack/test/dispatch/executor_test.rb b/actionpack/test/dispatch/executor_test.rb
index 28bb232ecd..8eb6450385 100644
--- a/actionpack/test/dispatch/executor_test.rb
+++ b/actionpack/test/dispatch/executor_test.rb
@@ -1,4 +1,6 @@
-require 'abstract_unit'
+# frozen_string_literal: true
+
+require "abstract_unit"
 
 class ExecutorTest < ActiveSupport::TestCase
   class MyBody < Array
@@ -119,8 +121,8 @@ class ExecutorTest < ActiveSupport::TestCase
 
   private
     def call_and_return_body(&block)
-      app = middleware(block || proc { [200, {}, 'response'] })
-      _, _, body = app.call({'rack.input' => StringIO.new('')})
+      app = middleware(block || proc { [200, {}, "response"] })
+      _, _, body = app.call("rack.input" => StringIO.new(""))
       body
     end
 
diff --git a/actionpack/test/dispatch/header_test.rb b/actionpack/test/dispatch/header_test.rb
index 7f1ef121b7..3a265a056b 100644
--- a/actionpack/test/dispatch/header_test.rb
+++ b/actionpack/test/dispatch/header_test.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require "abstract_unit"
 
 class HeaderTest < ActiveSupport::TestCase
@@ -18,14 +20,14 @@ class HeaderTest < ActiveSupport::TestCase
       "HTTP_REFERER" => "/some/page",
       "Host" => "http://test.com")
 
-    assert_equal({"Content-Type" => "application/json",
+    assert_equal({ "Content-Type" => "application/json",
                   "HTTP_REFERER" => "/some/page",
-                  "Host" => "http://test.com"}, headers.env)
+                  "Host" => "http://test.com" }, headers.env)
   end
 
   test "#env returns the headers as env variables" do
-    assert_equal({"CONTENT_TYPE" => "text/plain",
-                  "HTTP_REFERER" => "/some/page"}, @headers.env)
+    assert_equal({ "CONTENT_TYPE" => "text/plain",
+                  "HTTP_REFERER" => "/some/page" }, @headers.env)
   end
 
   test "#each iterates through the env variables" do
@@ -44,20 +46,20 @@ class HeaderTest < ActiveSupport::TestCase
 
   test "add to multivalued headers" do
     # Sets header when not present
-    @headers.add 'Foo', '1'
-    assert_equal '1', @headers['Foo']
+    @headers.add "Foo", "1"
+    assert_equal "1", @headers["Foo"]
 
     # Ignores nil values
-    @headers.add 'Foo', nil
-    assert_equal '1', @headers['Foo']
+    @headers.add "Foo", nil
+    assert_equal "1", @headers["Foo"]
 
     # Converts value to string
-    @headers.add 'Foo', 1
-    assert_equal '1,1', @headers['Foo']
+    @headers.add "Foo", 1
+    assert_equal "1,1", @headers["Foo"]
 
     # Case-insensitive
-    @headers.add 'fOo', 2
-    assert_equal '1,1,2', @headers['foO']
+    @headers.add "fOo", 2
+    assert_equal "1,1,2", @headers["foO"]
   end
 
   test "headers can contain numbers" do
@@ -76,9 +78,9 @@ class HeaderTest < ActiveSupport::TestCase
 
   test "key?" do
     assert @headers.key?("CONTENT_TYPE")
-    assert @headers.include?("CONTENT_TYPE")
+    assert_includes @headers, "CONTENT_TYPE"
     assert @headers.key?("Content-Type")
-    assert @headers.include?("Content-Type")
+    assert_includes @headers, "Content-Type"
   end
 
   test "fetch with block" do
@@ -105,28 +107,28 @@ class HeaderTest < ActiveSupport::TestCase
   test "#merge! headers with mutation" do
     @headers.merge!("Host" => "http://example.test",
                     "Content-Type" => "text/html")
-    assert_equal({"HTTP_HOST" => "http://example.test",
+    assert_equal({ "HTTP_HOST" => "http://example.test",
                   "CONTENT_TYPE" => "text/html",
-                  "HTTP_REFERER" => "/some/page"}, @headers.env)
+                  "HTTP_REFERER" => "/some/page" }, @headers.env)
   end
 
   test "#merge! env with mutation" do
     @headers.merge!("HTTP_HOST" => "http://first.com",
                     "CONTENT_TYPE" => "text/html")
-    assert_equal({"HTTP_HOST" => "http://first.com",
+    assert_equal({ "HTTP_HOST" => "http://first.com",
                   "CONTENT_TYPE" => "text/html",
-                  "HTTP_REFERER" => "/some/page"}, @headers.env)
+                  "HTTP_REFERER" => "/some/page" }, @headers.env)
   end
 
   test "merge without mutation" do
     combined = @headers.merge("HTTP_HOST" => "http://example.com",
                               "CONTENT_TYPE" => "text/html")
-    assert_equal({"HTTP_HOST" => "http://example.com",
+    assert_equal({ "HTTP_HOST" => "http://example.com",
                   "CONTENT_TYPE" => "text/html",
-                  "HTTP_REFERER" => "/some/page"}, combined.env)
+                  "HTTP_REFERER" => "/some/page" }, combined.env)
 
-    assert_equal({"CONTENT_TYPE" => "text/plain",
-                  "HTTP_REFERER" => "/some/page"}, @headers.env)
+    assert_equal({ "CONTENT_TYPE" => "text/plain",
+                  "HTTP_REFERER" => "/some/page" }, @headers.env)
   end
 
   test "env variables with . are not modified" do
@@ -151,11 +153,17 @@ class HeaderTest < ActiveSupport::TestCase
   end
 
   test "headers directly modifies the passed environment" do
-    env = {"HTTP_REFERER" => "/"}
+    env = { "HTTP_REFERER" => "/" }
     headers = make_headers(env)
-    headers['Referer'] = "http://example.com/"
+    headers["Referer"] = "http://example.com/"
     headers.merge! "CONTENT_TYPE" => "text/plain"
-    assert_equal({"HTTP_REFERER"=>"http://example.com/",
-                  "CONTENT_TYPE"=>"text/plain"}, env)
+    assert_equal({ "HTTP_REFERER" => "http://example.com/",
+                  "CONTENT_TYPE" => "text/plain" }, env)
+  end
+
+  test "fetch exception" do
+    assert_raises KeyError do
+      @headers.fetch(:some_key_that_doesnt_exist)
+    end
   end
 end
diff --git a/actionpack/test/dispatch/live_response_test.rb b/actionpack/test/dispatch/live_response_test.rb
index de57c4be1d..2901148a9e 100644
--- a/actionpack/test/dispatch/live_response_test.rb
+++ b/actionpack/test/dispatch/live_response_test.rb
@@ -1,5 +1,7 @@
-require 'abstract_unit'
-require 'concurrent/atomic/count_down_latch'
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "concurrent/atomic/count_down_latch"
 
 module ActionController
   module Live
@@ -10,7 +12,7 @@ module ActionController
       end
 
       def test_header_merge
-        header = @response.header.merge('Foo' => 'Bar')
+        header = @response.header.merge("Foo" => "Bar")
         assert_kind_of(ActionController::Live::Response::Header, header)
         assert_not_equal header, @response.header
       end
@@ -18,7 +20,7 @@ module ActionController
       def test_initialize_with_default_headers
         r = Class.new(Live::Response) do
           def self.default_headers
-            { 'omg' => 'g' }
+            { "omg" => "g" }
           end
         end
 
@@ -30,38 +32,38 @@ module ActionController
         latch = Concurrent::CountDownLatch.new
 
         t = Thread.new {
-          @response.stream.write 'foo'
+          @response.stream.write "foo"
           latch.wait
           @response.stream.close
         }
 
         @response.await_commit
         @response.each do |part|
-          assert_equal 'foo', part
+          assert_equal "foo", part
           latch.count_down
         end
         assert t.join
       end
 
       def test_setting_body_populates_buffer
-        @response.body = 'omg'
+        @response.body = "omg"
         @response.close
-        assert_equal ['omg'], @response.body_parts
+        assert_equal ["omg"], @response.body_parts
       end
 
       def test_cache_control_is_set
-        @response.stream.write 'omg'
-        assert_equal 'no-cache', @response.headers['Cache-Control']
+        @response.stream.write "omg"
+        assert_equal "no-cache", @response.headers["Cache-Control"]
       end
 
       def test_content_length_is_removed
-        @response.headers['Content-Length'] = "1234"
-        @response.stream.write 'omg'
-        assert_nil @response.headers['Content-Length']
+        @response.headers["Content-Length"] = "1234"
+        @response.stream.write "omg"
+        assert_nil @response.headers["Content-Length"]
       end
 
       def test_headers_cannot_be_written_after_webserver_reads
-        @response.stream.write 'omg'
+        @response.stream.write "omg"
         latch = Concurrent::CountDownLatch.new
 
         t = Thread.new {
@@ -73,10 +75,10 @@ module ActionController
         latch.wait
         assert @response.headers.frozen?
         e = assert_raises(ActionDispatch::IllegalStateError) do
-          @response.headers['Content-Length'] = "zomg"
+          @response.headers["Content-Length"] = "zomg"
         end
 
-        assert_equal 'header already sent', e.message
+        assert_equal "header already sent", e.message
         @response.stream.close
         t.join
       end
@@ -87,9 +89,9 @@ module ActionController
         @response.each { |x| }
 
         e = assert_raises(ActionDispatch::IllegalStateError) do
-          @response.headers['Content-Length'] = "zomg"
+          @response.headers["Content-Length"] = "zomg"
         end
-        assert_equal 'header already sent', e.message
+        assert_equal "header already sent", e.message
       end
     end
   end
diff --git a/actionpack/test/dispatch/mapper_test.rb b/actionpack/test/dispatch/mapper_test.rb
index 69098326b9..969a08efed 100644
--- a/actionpack/test/dispatch/mapper_test.rb
+++ b/actionpack/test/dispatch/mapper_test.rb
@@ -1,4 +1,6 @@
-require 'abstract_unit'
+# frozen_string_literal: true
+
+require "abstract_unit"
 
 module ActionDispatch
   module Routing
@@ -50,15 +52,15 @@ module ActionDispatch
         fakeset = FakeSet.new
         mapper = Mapper.new fakeset
         assert_raises(ArgumentError) do
-          mapper.match '/', :to => 'posts#index', :as => :main
+          mapper.match "/", to: "posts#index", as: :main
         end
       end
 
       def test_unscoped_formatted
         fakeset = FakeSet.new
         mapper = Mapper.new fakeset
-        mapper.get '/foo', :to => 'posts#index', :as => :main, :format => true
-        assert_equal({:controller=>"posts", :action=>"index"},
+        mapper.get "/foo", to: "posts#index", as: :main, format: true
+        assert_equal({ controller: "posts", action: "index" },
                      fakeset.defaults.first)
         assert_equal "/foo.:format", fakeset.asts.first.to_s
       end
@@ -67,9 +69,9 @@ module ActionDispatch
         fakeset = FakeSet.new
         mapper = Mapper.new fakeset
         mapper.scope(format: true) do
-          mapper.get '/foo', :to => 'posts#index', :as => :main
+          mapper.get "/foo", to: "posts#index", as: :main
         end
-        assert_equal({:controller=>"posts", :action=>"index"},
+        assert_equal({ controller: "posts", action: "index" },
                      fakeset.defaults.first)
         assert_equal "/foo.:format", fakeset.asts.first.to_s
       end
@@ -78,18 +80,18 @@ module ActionDispatch
         fakeset = FakeSet.new
         mapper = Mapper.new fakeset
         mapper.scope(omg: :awesome) do
-          mapper.get '/', :to => 'posts#index', :as => :main
+          mapper.get "/", to: "posts#index", as: :main
         end
-        assert_equal({:omg=>:awesome, :controller=>"posts", :action=>"index"},
+        assert_equal({ omg: :awesome, controller: "posts", action: "index" },
                      fakeset.defaults.first)
         assert_equal("GET", fakeset.routes.first.verb)
       end
 
       def test_mapping_requirements
-        options = { }
+        options = {}
         scope = Mapper::Scope.new({})
-        ast = Journey::Parser.parse '/store/:name(*rest)'
-        m = Mapper::Mapping.build(scope, FakeSet.new, ast, 'foo', 'bar', nil, [:get], nil, {}, true, options)
+        ast = Journey::Parser.parse "/store/:name(*rest)"
+        m = Mapper::Mapping.build(scope, FakeSet.new, ast, "foo", "bar", nil, [:get], nil, {}, true, options)
         assert_equal(/.+?/, m.requirements[:rest])
       end
 
@@ -97,16 +99,28 @@ module ActionDispatch
         fakeset = FakeSet.new
         mapper = Mapper.new fakeset
         mapper.scope(via: :put) do
-          mapper.match '/', :to => 'posts#index', :as => :main
+          mapper.match "/", to: "posts#index", as: :main
         end
         assert_equal("PUT", fakeset.routes.first.verb)
       end
 
+      def test_to_scope
+        fakeset = FakeSet.new
+        mapper = Mapper.new fakeset
+        mapper.scope(to: "posts#index") do
+          mapper.get :all
+          mapper.post :most
+        end
+
+        assert_equal "posts#index", fakeset.routes.to_a[0].defaults[:to]
+        assert_equal "posts#index", fakeset.routes.to_a[1].defaults[:to]
+      end
+
       def test_map_slash
         fakeset = FakeSet.new
         mapper = Mapper.new fakeset
-        mapper.get '/', :to => 'posts#index', :as => :main
-        assert_equal '/', fakeset.asts.first.to_s
+        mapper.get "/", to: "posts#index", as: :main
+        assert_equal "/", fakeset.asts.first.to_s
       end
 
       def test_map_more_slashes
@@ -114,31 +128,31 @@ module ActionDispatch
         mapper = Mapper.new fakeset
 
         # FIXME: is this a desired behavior?
-        mapper.get '/one/two/', :to => 'posts#index', :as => :main
-        assert_equal '/one/two(.:format)', fakeset.asts.first.to_s
+        mapper.get "/one/two/", to: "posts#index", as: :main
+        assert_equal "/one/two(.:format)", fakeset.asts.first.to_s
       end
 
       def test_map_wildcard
         fakeset = FakeSet.new
         mapper = Mapper.new fakeset
-        mapper.get '/*path', :to => 'pages#show'
-        assert_equal '/*path(.:format)', fakeset.asts.first.to_s
+        mapper.get "/*path", to: "pages#show"
+        assert_equal "/*path(.:format)", fakeset.asts.first.to_s
         assert_equal(/.+?/, fakeset.requirements.first[:path])
       end
 
       def test_map_wildcard_with_other_element
         fakeset = FakeSet.new
         mapper = Mapper.new fakeset
-        mapper.get '/*path/foo/:bar', :to => 'pages#show'
-        assert_equal '/*path/foo/:bar(.:format)', fakeset.asts.first.to_s
+        mapper.get "/*path/foo/:bar", to: "pages#show"
+        assert_equal "/*path/foo/:bar(.:format)", fakeset.asts.first.to_s
         assert_equal(/.+?/, fakeset.requirements.first[:path])
       end
 
       def test_map_wildcard_with_multiple_wildcard
         fakeset = FakeSet.new
         mapper = Mapper.new fakeset
-        mapper.get '/*foo/*bar', :to => 'pages#show'
-        assert_equal '/*foo/*bar(.:format)', fakeset.asts.first.to_s
+        mapper.get "/*foo/*bar", to: "pages#show"
+        assert_equal "/*foo/*bar(.:format)", fakeset.asts.first.to_s
         assert_equal(/.+?/, fakeset.requirements.first[:foo])
         assert_equal(/.+?/, fakeset.requirements.first[:bar])
       end
@@ -146,16 +160,16 @@ module ActionDispatch
       def test_map_wildcard_with_format_false
         fakeset = FakeSet.new
         mapper = Mapper.new fakeset
-        mapper.get '/*path', :to => 'pages#show', :format => false
-        assert_equal '/*path', fakeset.asts.first.to_s
+        mapper.get "/*path", to: "pages#show", format: false
+        assert_equal "/*path", fakeset.asts.first.to_s
         assert_nil fakeset.requirements.first[:path]
       end
 
       def test_map_wildcard_with_format_true
         fakeset = FakeSet.new
         mapper = Mapper.new fakeset
-        mapper.get '/*path', :to => 'pages#show', :format => true
-        assert_equal '/*path.:format', fakeset.asts.first.to_s
+        mapper.get "/*path", to: "pages#show", format: true
+        assert_equal "/*path.:format", fakeset.asts.first.to_s
       end
 
       def test_raising_error_when_path_is_not_passed
diff --git a/actionpack/test/dispatch/middleware_stack_test.rb b/actionpack/test/dispatch/middleware_stack_test.rb
index a8c8e0784f..e9f7ad41dd 100644
--- a/actionpack/test/dispatch/middleware_stack_test.rb
+++ b/actionpack/test/dispatch/middleware_stack_test.rb
@@ -1,4 +1,6 @@
-require 'abstract_unit'
+# frozen_string_literal: true
+
+require "abstract_unit"
 
 class MiddlewareStackTest < ActiveSupport::TestCase
   class FooMiddleware; end
@@ -18,14 +20,6 @@ class MiddlewareStackTest < ActiveSupport::TestCase
     @stack.use BarMiddleware
   end
 
-  def test_delete_with_string_is_deprecated
-    assert_deprecated do
-      assert_difference "@stack.size", -1 do
-        @stack.delete FooMiddleware.name
-      end
-    end
-  end
-
   def test_delete_works
     assert_difference "@stack.size", -1 do
       @stack.delete FooMiddleware
@@ -39,30 +33,12 @@ class MiddlewareStackTest < ActiveSupport::TestCase
     assert_equal BazMiddleware, @stack.last.klass
   end
 
-  test "use should push middleware as a string onto the stack" do
-    assert_deprecated do
-      assert_difference "@stack.size" do
-        @stack.use "MiddlewareStackTest::BazMiddleware"
-      end
-      assert_equal BazMiddleware, @stack.last.klass
-    end
-  end
-
-  test "use should push middleware as a symbol onto the stack" do
-    assert_deprecated do
-      assert_difference "@stack.size" do
-        @stack.use :"MiddlewareStackTest::BazMiddleware"
-      end
-      assert_equal BazMiddleware, @stack.last.klass
-    end
-  end
-
   test "use should push middleware class with arguments onto the stack" do
     assert_difference "@stack.size" do
-      @stack.use BazMiddleware, true, :foo => "bar"
+      @stack.use BazMiddleware, true, foo: "bar"
     end
     assert_equal BazMiddleware, @stack.last.klass
-    assert_equal([true, {:foo => "bar"}], @stack.last.args)
+    assert_equal([true, { foo: "bar" }], @stack.last.args)
   end
 
   test "use should push middleware class with block arguments onto the stack" do
@@ -102,15 +78,13 @@ class MiddlewareStackTest < ActiveSupport::TestCase
 
   test "swaps one middleware out for same middleware class" do
     assert_equal FooMiddleware, @stack[0].klass
-    @stack.swap(FooMiddleware, FooMiddleware, Proc.new { |env| [500, {}, ['error!']] })
+    @stack.swap(FooMiddleware, FooMiddleware, Proc.new { |env| [500, {}, ["error!"]] })
     assert_equal FooMiddleware, @stack[0].klass
   end
 
   test "unshift adds a new middleware at the beginning of the stack" do
-    assert_deprecated do
-      @stack.unshift :"MiddlewareStackTest::BazMiddleware"
-      assert_equal BazMiddleware, @stack.first.klass
-    end
+    @stack.unshift MiddlewareStackTest::BazMiddleware
+    assert_equal BazMiddleware, @stack.first.klass
   end
 
   test "raise an error on invalid index" do
@@ -123,15 +97,6 @@ class MiddlewareStackTest < ActiveSupport::TestCase
     end
   end
 
-  test "lazy evaluates middleware class" do
-    assert_deprecated do
-      assert_difference "@stack.size" do
-        @stack.use "MiddlewareStackTest::BazMiddleware"
-      end
-      assert_equal BazMiddleware, @stack.last.klass
-    end
-  end
-
   test "can check if Middleware are equal - Class" do
     assert_equal @stack.last, BarMiddleware
   end
diff --git a/actionpack/test/dispatch/mime_type_test.rb b/actionpack/test/dispatch/mime_type_test.rb
index 672b272590..6854783386 100644
--- a/actionpack/test/dispatch/mime_type_test.rb
+++ b/actionpack/test/dispatch/mime_type_test.rb
@@ -1,9 +1,11 @@
-require 'abstract_unit'
+# frozen_string_literal: true
+
+require "abstract_unit"
 
 class MimeTypeTest < ActiveSupport::TestCase
   test "parse single" do
     Mime::LOOKUP.each_key do |mime_type|
-      unless mime_type == 'image/*'
+      unless mime_type == "image/*"
         assert_equal [Mime::Type.lookup(mime_type)], Mime::Type.parse(mime_type)
       end
     end
@@ -15,7 +17,7 @@ class MimeTypeTest < ActiveSupport::TestCase
     begin
       mime = Mime::Type.register("text/x-mobile", :mobile)
       assert_equal mime, Mime[:mobile]
-      assert_equal mime, Mime::Type.lookup('text/x-mobile')
+      assert_equal mime, Mime::Type.lookup("text/x-mobile")
       assert_equal mime, Mime::Type.lookup_by_extension(:mobile)
 
       Mime::Type.unregister(:mobile)
@@ -28,41 +30,41 @@ class MimeTypeTest < ActiveSupport::TestCase
 
   test "parse text with trailing star at the beginning" do
     accept = "text/*, text/html, application/json, multipart/form-data"
-    expect = [Mime[:html], Mime[:text], Mime[:js], Mime[:css], Mime[:ics], Mime[:csv], Mime[:vcf], Mime[:xml], Mime[:yaml], Mime[:json], Mime[:multipart_form]]
+    expect = [Mime[:html], Mime[:text], Mime[:js], Mime[:css], Mime[:ics], Mime[:csv], Mime[:vcf], Mime[:vtt], Mime[:xml], Mime[:yaml], Mime[:json], Mime[:multipart_form]]
     parsed = Mime::Type.parse(accept)
-    assert_equal expect, parsed
+    assert_equal expect.map(&:to_s), parsed.map(&:to_s)
   end
 
   test "parse text with trailing star in the end" do
     accept = "text/html, application/json, multipart/form-data, text/*"
-    expect = [Mime[:html], Mime[:json], Mime[:multipart_form], Mime[:text], Mime[:js], Mime[:css], Mime[:ics], Mime[:csv], Mime[:vcf], Mime[:xml], Mime[:yaml]]
+    expect = [Mime[:html], Mime[:json], Mime[:multipart_form], Mime[:text], Mime[:js], Mime[:css], Mime[:ics], Mime[:csv], Mime[:vcf], Mime[:vtt], Mime[:xml], Mime[:yaml]]
     parsed = Mime::Type.parse(accept)
-    assert_equal expect, parsed
+    assert_equal expect.map(&:to_s), parsed.map(&:to_s)
   end
 
   test "parse text with trailing star" do
     accept = "text/*"
-    expect = [Mime[:html], Mime[:text], Mime[:js], Mime[:css], Mime[:ics], Mime[:csv], Mime[:vcf], Mime[:xml], Mime[:yaml], Mime[:json]]
+    expect = [Mime[:html], Mime[:text], Mime[:js], Mime[:css], Mime[:ics], Mime[:csv], Mime[:vcf], Mime[:vtt], Mime[:xml], Mime[:yaml], Mime[:json]]
     parsed = Mime::Type.parse(accept)
-    assert_equal expect, parsed
+    assert_equal expect.map(&:to_s).sort!, parsed.map(&:to_s).sort!
   end
 
   test "parse application with trailing star" do
     accept = "application/*"
     expect = [Mime[:html], Mime[:js], Mime[:xml], Mime[:rss], Mime[:atom], Mime[:yaml], Mime[:url_encoded_form], Mime[:json], Mime[:pdf], Mime[:zip], Mime[:gzip]]
     parsed = Mime::Type.parse(accept)
-    assert_equal expect, parsed
+    assert_equal expect.map(&:to_s).sort!, parsed.map(&:to_s).sort!
   end
 
   test "parse without q" do
     accept = "text/xml,application/xhtml+xml,text/yaml,application/xml,text/html,image/png,text/plain,application/pdf,*/*"
-    expect = [Mime[:html], Mime[:xml], Mime[:yaml], Mime[:png], Mime[:text], Mime[:pdf], '*/*']
+    expect = [Mime[:html], Mime[:xml], Mime[:yaml], Mime[:png], Mime[:text], Mime[:pdf], "*/*"]
     assert_equal expect.map(&:to_s), Mime::Type.parse(accept).map(&:to_s)
   end
 
   test "parse with q" do
     accept = "text/xml,application/xhtml+xml,text/yaml; q=0.3,application/xml,text/html; q=0.8,image/png,text/plain; q=0.5,application/pdf,*/*; q=0.2"
-    expect = [Mime[:html], Mime[:xml], Mime[:png], Mime[:pdf], Mime[:text], Mime[:yaml], '*/*']
+    expect = [Mime[:html], Mime[:xml], Mime[:png], Mime[:pdf], Mime[:text], Mime[:yaml], "*/*"]
     assert_equal expect.map(&:to_s), Mime::Type.parse(accept).map(&:to_s)
   end
 
@@ -81,7 +83,7 @@ class MimeTypeTest < ActiveSupport::TestCase
   # Accept header send with user HTTP_USER_AGENT: Sunrise/0.42j (Windows XP)
   test "parse broken acceptlines" do
     accept = "text/xml,application/xml,application/xhtml+xml,text/html;q=0.9,text/plain;q=0.8,image/*,,*/*;q=0.5"
-    expect = [Mime[:html], Mime[:xml], "image/*", Mime[:text], '*/*']
+    expect = [Mime[:html], Mime[:xml], "image/*", Mime[:text], "*/*"]
     assert_equal expect.map(&:to_s), Mime::Type.parse(accept).map(&:to_s)
   end
 
@@ -89,7 +91,7 @@ class MimeTypeTest < ActiveSupport::TestCase
   #  (compatible; MSIE 6.0; Windows NT 5.1; SV1; .NET CLR 1.1.4322; InfoPath.1)
   test "parse other broken acceptlines" do
     accept = "image/gif, image/x-xbitmap, image/jpeg, image/pjpeg, application/x-shockwave-flash, application/vnd.ms-excel, application/vnd.ms-powerpoint, application/msword,  , pronto/1.00.00, sslvpn/1.00.00.00, */*"
-    expect = ['image/gif', 'image/x-xbitmap', 'image/jpeg','image/pjpeg', 'application/x-shockwave-flash', 'application/vnd.ms-excel', 'application/vnd.ms-powerpoint', 'application/msword', 'pronto/1.00.00', 'sslvpn/1.00.00.00', '*/*']
+    expect = ["image/gif", "image/x-xbitmap", "image/jpeg", "image/pjpeg", "application/x-shockwave-flash", "application/vnd.ms-excel", "application/vnd.ms-powerpoint", "application/msword", "pronto/1.00.00", "sslvpn/1.00.00.00", "*/*"]
     assert_equal expect.map(&:to_s), Mime::Type.parse(accept).map(&:to_s)
   end
 
@@ -141,14 +143,14 @@ class MimeTypeTest < ActiveSupport::TestCase
   test "register alias" do
     begin
       Mime::Type.register_alias "application/xhtml+xml", :foobar
-      assert_equal Mime[:html], Mime::EXTENSION_LOOKUP['foobar']
+      assert_equal Mime[:html], Mime::EXTENSION_LOOKUP["foobar"]
     ensure
       Mime::Type.unregister(:foobar)
     end
   end
 
   test "type should be equal to symbol" do
-    assert_equal Mime[:html], 'application/xhtml+xml'
+    assert_equal Mime[:html], "application/xhtml+xml"
     assert_equal Mime[:html], :html
   end
 
@@ -167,18 +169,6 @@ class MimeTypeTest < ActiveSupport::TestCase
     end
   end
 
-  test "deprecated lookup" do
-    assert_deprecated do
-      Mime::HTML
-    end
-  end
-
-  test "deprecated const_defined?" do
-    assert_deprecated do
-      Mime.const_defined? :HTML
-    end
-  end
-
   test "references gives preference to symbols before strings" do
     assert_equal :html, Mime[:html].ref
     another = Mime::Type.lookup("foo/bar")
@@ -192,6 +182,6 @@ class MimeTypeTest < ActiveSupport::TestCase
     assert Mime[:js] !~ "text/html"
     assert !(Mime[:js] !~ "text/javascript")
     assert !(Mime[:js] !~ "application/javascript")
-    assert Mime[:html] =~ 'application/xhtml+xml'
+    assert Mime[:html] =~ "application/xhtml+xml"
   end
 end
diff --git a/actionpack/test/dispatch/mount_test.rb b/actionpack/test/dispatch/mount_test.rb
index d027f09762..f6cf653980 100644
--- a/actionpack/test/dispatch/mount_test.rb
+++ b/actionpack/test/dispatch/mount_test.rb
@@ -1,5 +1,7 @@
-require 'abstract_unit'
-require 'rails/engine'
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "rails/engine"
 
 class TestRoutingMount < ActionDispatch::IntegrationTest
   Router = ActionDispatch::Routing::RouteSet.new
@@ -15,30 +17,30 @@ class TestRoutingMount < ActionDispatch::IntegrationTest
     def self.routes; Object.new; end
 
     def self.call(env)
-      [200, {"Content-Type" => "text/html"}, ["OK"]]
+      [200, { "Content-Type" => "text/html" }, ["OK"]]
     end
   end
 
   Router.draw do
     SprocketsApp = lambda { |env|
-      [200, {"Content-Type" => "text/html"}, ["#{env["SCRIPT_NAME"]} -- #{env["PATH_INFO"]}"]]
+      [200, { "Content-Type" => "text/html" }, ["#{env["SCRIPT_NAME"]} -- #{env["PATH_INFO"]}"]]
     }
 
-    mount SprocketsApp, :at => "/sprockets"
+    mount SprocketsApp, at: "/sprockets"
     mount SprocketsApp => "/shorthand"
 
-    mount SinatraLikeApp, :at => "/fakeengine", :as => :fake
-    mount SinatraLikeApp, :at => "/getfake", :via => :get
+    mount SinatraLikeApp, at: "/fakeengine", as: :fake
+    mount SinatraLikeApp, at: "/getfake", via: :get
 
     scope "/its_a" do
-      mount SprocketsApp, :at => "/sprocket"
+      mount SprocketsApp, at: "/sprocket"
     end
 
     resources :users do
-      mount AppWithRoutes, :at => "/fakeengine", :as => :fake_mounted_at_resource
+      mount AppWithRoutes, at: "/fakeengine", as: :fake_mounted_at_resource
     end
 
-    mount SprocketsApp, :at => "/", :via => :get
+    mount SprocketsApp, at: "/", via: :get
   end
 
   APP = RoutedRackApp.new Router
@@ -64,7 +66,7 @@ class TestRoutingMount < ActionDispatch::IntegrationTest
   end
 
   def test_mounting_works_with_nested_script_name
-    get "/foo/sprockets/omg", headers: { 'SCRIPT_NAME' => '/foo', 'PATH_INFO' => '/sprockets/omg' }
+    get "/foo/sprockets/omg", headers: { "SCRIPT_NAME" => "/foo", "PATH_INFO" => "/sprockets/omg" }
     assert_equal "/foo/sprockets -- /omg", response.body
   end
 
diff --git a/actionpack/test/dispatch/prefix_generation_test.rb b/actionpack/test/dispatch/prefix_generation_test.rb
index b8f0ffb64a..85ea04356a 100644
--- a/actionpack/test/dispatch/prefix_generation_test.rb
+++ b/actionpack/test/dispatch/prefix_generation_test.rb
@@ -1,6 +1,8 @@
-require 'abstract_unit'
-require 'rack/test'
-require 'rails/engine'
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "rack/test"
+require "rails/engine"
 
 module TestGenerationPrefix
   class Post
@@ -11,7 +13,7 @@ module TestGenerationPrefix
     end
 
     def self.model_name
-      klass = "Post"
+      klass = "Post".dup
       def klass.name; self end
 
       ActiveModel::Name.new(klass)
@@ -22,46 +24,44 @@ module TestGenerationPrefix
   end
 
   class WithMountedEngine < ActionDispatch::IntegrationTest
-    include Rack::Test::Methods
-
     class BlogEngine < Rails::Engine
       routes.draw do
-        get "/posts/:id", :to => "inside_engine_generating#show", :as => :post
-        get "/posts", :to => "inside_engine_generating#index", :as => :posts
-        get "/url_to_application", :to => "inside_engine_generating#url_to_application"
-        get "/polymorphic_path_for_engine", :to => "inside_engine_generating#polymorphic_path_for_engine"
-        get "/conflicting_url", :to => "inside_engine_generating#conflicting"
-        get "/foo", :to => "never#invoked", :as => :named_helper_that_should_be_invoked_only_in_respond_to_test
-
-        get "/relative_path_root",       :to => redirect("")
-        get "/relative_path_redirect",   :to => redirect("foo")
-        get "/relative_option_root",     :to => redirect(:path => "")
-        get "/relative_option_redirect", :to => redirect(:path => "foo")
-        get "/relative_custom_root",     :to => redirect { |params, request| "" }
-        get "/relative_custom_redirect", :to => redirect { |params, request| "foo" }
-
-        get "/absolute_path_root",       :to => redirect("/")
-        get "/absolute_path_redirect",   :to => redirect("/foo")
-        get "/absolute_option_root",     :to => redirect(:path => "/")
-        get "/absolute_option_redirect", :to => redirect(:path => "/foo")
-        get "/absolute_custom_root",     :to => redirect { |params, request| "/" }
-        get "/absolute_custom_redirect", :to => redirect { |params, request| "/foo" }
+        get "/posts/:id", to: "inside_engine_generating#show", as: :post
+        get "/posts", to: "inside_engine_generating#index", as: :posts
+        get "/url_to_application", to: "inside_engine_generating#url_to_application"
+        get "/polymorphic_path_for_engine", to: "inside_engine_generating#polymorphic_path_for_engine"
+        get "/conflicting_url", to: "inside_engine_generating#conflicting"
+        get "/foo", to: "never#invoked", as: :named_helper_that_should_be_invoked_only_in_respond_to_test
+
+        get "/relative_path_root",       to: redirect("")
+        get "/relative_path_redirect",   to: redirect("foo")
+        get "/relative_option_root",     to: redirect(path: "")
+        get "/relative_option_redirect", to: redirect(path: "foo")
+        get "/relative_custom_root",     to: redirect { |params, request| "" }
+        get "/relative_custom_redirect", to: redirect { |params, request| "foo" }
+
+        get "/absolute_path_root",       to: redirect("/")
+        get "/absolute_path_redirect",   to: redirect("/foo")
+        get "/absolute_option_root",     to: redirect(path: "/")
+        get "/absolute_option_redirect", to: redirect(path: "/foo")
+        get "/absolute_custom_root",     to: redirect { |params, request| "/" }
+        get "/absolute_custom_redirect", to: redirect { |params, request| "/foo" }
       end
     end
 
     class RailsApplication < Rails::Engine
       routes.draw do
-        scope "/:omg", :omg => "awesome" do
+        scope "/:omg", omg: "awesome" do
           mount BlogEngine => "/blog", :as => "blog_engine"
         end
-        get "/posts/:id", :to => "outside_engine_generating#post", :as => :post
-        get "/generate", :to => "outside_engine_generating#index"
-        get "/polymorphic_path_for_app", :to => "outside_engine_generating#polymorphic_path_for_app"
-        get "/polymorphic_path_for_engine", :to => "outside_engine_generating#polymorphic_path_for_engine"
-        get "/polymorphic_with_url_for", :to => "outside_engine_generating#polymorphic_with_url_for"
-        get "/conflicting_url", :to => "outside_engine_generating#conflicting"
-        get "/ivar_usage", :to => "outside_engine_generating#ivar_usage"
-        root :to => "outside_engine_generating#index"
+        get "/posts/:id", to: "outside_engine_generating#post", as: :post
+        get "/generate", to: "outside_engine_generating#index"
+        get "/polymorphic_path_for_app", to: "outside_engine_generating#polymorphic_path_for_app"
+        get "/polymorphic_path_for_engine", to: "outside_engine_generating#polymorphic_path_for_engine"
+        get "/polymorphic_with_url_for", to: "outside_engine_generating#polymorphic_with_url_for"
+        get "/conflicting_url", to: "outside_engine_generating#conflicting"
+        get "/ivar_usage", to: "outside_engine_generating#ivar_usage"
+        root to: "outside_engine_generating#index"
       end
     end
 
@@ -81,9 +81,9 @@ module TestGenerationPrefix
       end
 
       def url_to_application
-        path = main_app.url_for(:controller => "outside_engine_generating",
-                                :action => "index",
-                                :only_path => true)
+        path = main_app.url_for(controller: "outside_engine_generating",
+                                action: "index",
+                                only_path: true)
         render plain: path
       end
 
@@ -153,114 +153,114 @@ module TestGenerationPrefix
     # Inside Engine
     test "[ENGINE] generating engine's url use SCRIPT_NAME from request" do
       get "/pure-awesomeness/blog/posts/1"
-      assert_equal "/pure-awesomeness/blog/posts/1", last_response.body
+      assert_equal "/pure-awesomeness/blog/posts/1", response.body
     end
 
     test "[ENGINE] generating application's url never uses SCRIPT_NAME from request" do
       get "/pure-awesomeness/blog/url_to_application"
-      assert_equal "/generate", last_response.body
+      assert_equal "/generate", response.body
     end
 
     test "[ENGINE] generating engine's url with polymorphic path" do
       get "/pure-awesomeness/blog/polymorphic_path_for_engine"
-      assert_equal "/pure-awesomeness/blog/posts/1", last_response.body
+      assert_equal "/pure-awesomeness/blog/posts/1", response.body
     end
 
     test "[ENGINE] url_helpers from engine have higher priority than application's url_helpers" do
       get "/awesome/blog/conflicting_url"
-      assert_equal "engine", last_response.body
+      assert_equal "engine", response.body
     end
 
     test "[ENGINE] relative path root uses SCRIPT_NAME from request" do
       get "/awesome/blog/relative_path_root"
-      verify_redirect "http://example.org/awesome/blog"
+      verify_redirect "http://www.example.com/awesome/blog"
     end
 
     test "[ENGINE] relative path redirect uses SCRIPT_NAME from request" do
       get "/awesome/blog/relative_path_redirect"
-      verify_redirect "http://example.org/awesome/blog/foo"
+      verify_redirect "http://www.example.com/awesome/blog/foo"
     end
 
     test "[ENGINE] relative option root uses SCRIPT_NAME from request" do
       get "/awesome/blog/relative_option_root"
-      verify_redirect "http://example.org/awesome/blog"
+      verify_redirect "http://www.example.com/awesome/blog"
     end
 
     test "[ENGINE] relative option redirect uses SCRIPT_NAME from request" do
       get "/awesome/blog/relative_option_redirect"
-      verify_redirect "http://example.org/awesome/blog/foo"
+      verify_redirect "http://www.example.com/awesome/blog/foo"
     end
 
     test "[ENGINE] relative custom root uses SCRIPT_NAME from request" do
       get "/awesome/blog/relative_custom_root"
-      verify_redirect "http://example.org/awesome/blog"
+      verify_redirect "http://www.example.com/awesome/blog"
     end
 
     test "[ENGINE] relative custom redirect uses SCRIPT_NAME from request" do
       get "/awesome/blog/relative_custom_redirect"
-      verify_redirect "http://example.org/awesome/blog/foo"
+      verify_redirect "http://www.example.com/awesome/blog/foo"
     end
 
     test "[ENGINE] absolute path root doesn't use SCRIPT_NAME from request" do
       get "/awesome/blog/absolute_path_root"
-      verify_redirect "http://example.org/"
+      verify_redirect "http://www.example.com/"
     end
 
     test "[ENGINE] absolute path redirect doesn't use SCRIPT_NAME from request" do
       get "/awesome/blog/absolute_path_redirect"
-      verify_redirect "http://example.org/foo"
+      verify_redirect "http://www.example.com/foo"
     end
 
     test "[ENGINE] absolute option root doesn't use SCRIPT_NAME from request" do
       get "/awesome/blog/absolute_option_root"
-      verify_redirect "http://example.org/"
+      verify_redirect "http://www.example.com/"
     end
 
     test "[ENGINE] absolute option redirect doesn't use SCRIPT_NAME from request" do
       get "/awesome/blog/absolute_option_redirect"
-      verify_redirect "http://example.org/foo"
+      verify_redirect "http://www.example.com/foo"
     end
 
     test "[ENGINE] absolute custom root doesn't use SCRIPT_NAME from request" do
       get "/awesome/blog/absolute_custom_root"
-      verify_redirect "http://example.org/"
+      verify_redirect "http://www.example.com/"
     end
 
     test "[ENGINE] absolute custom redirect doesn't use SCRIPT_NAME from request" do
       get "/awesome/blog/absolute_custom_redirect"
-      verify_redirect "http://example.org/foo"
+      verify_redirect "http://www.example.com/foo"
     end
 
     # Inside Application
     test "[APP] generating engine's route includes prefix" do
       get "/generate"
-      assert_equal "/awesome/blog/posts/1", last_response.body
+      assert_equal "/awesome/blog/posts/1", response.body
     end
 
     test "[APP] generating engine's route includes default_url_options[:script_name]" do
-      RailsApplication.routes.default_url_options = {:script_name => "/something"}
+      RailsApplication.routes.default_url_options = { script_name: "/something" }
       get "/generate"
-      assert_equal "/something/awesome/blog/posts/1", last_response.body
+      assert_equal "/something/awesome/blog/posts/1", response.body
     end
 
     test "[APP] generating engine's url with polymorphic path" do
       get "/polymorphic_path_for_engine"
-      assert_equal "/awesome/blog/posts/1", last_response.body
+      assert_equal "/awesome/blog/posts/1", response.body
     end
 
     test "polymorphic_path_for_app" do
       get "/polymorphic_path_for_app"
-      assert_equal "/posts/1", last_response.body
+      assert_equal "/posts/1", response.body
     end
 
     test "[APP] generating engine's url with url_for(@post)" do
       get "/polymorphic_with_url_for"
-      assert_equal "http://example.org/awesome/blog/posts/1", last_response.body
+      assert_equal "http://www.example.com/awesome/blog/posts/1", response.body
     end
 
     test "[APP] instance variable with same name as engine" do
       get "/ivar_usage"
-      assert_equal "/awesome/blog/posts/1", last_response.body
+      assert_equal "/awesome/blog/posts/1", response.body
     end
 
     # Inside any Object
@@ -269,16 +269,16 @@ module TestGenerationPrefix
     end
 
     test "[OBJECT] generating engine's route includes prefix" do
-      assert_equal "/awesome/blog/posts/1", engine_object.post_path(:id => 1)
+      assert_equal "/awesome/blog/posts/1", engine_object.post_path(id: 1)
     end
 
     test "[OBJECT] generating engine's route includes dynamic prefix" do
-      assert_equal "/pure-awesomeness/blog/posts/3", engine_object.post_path(:id => 3, :omg => "pure-awesomeness")
+      assert_equal "/pure-awesomeness/blog/posts/3", engine_object.post_path(id: 3, omg: "pure-awesomeness")
     end
 
     test "[OBJECT] generating engine's route includes default_url_options[:script_name]" do
-      RailsApplication.routes.default_url_options = {:script_name => "/something"}
-      assert_equal "/something/pure-awesomeness/blog/posts/3", engine_object.post_path(:id => 3, :omg => "pure-awesomeness")
+      RailsApplication.routes.default_url_options = { script_name: "/something" }
+      assert_equal "/something/pure-awesomeness/blog/posts/3", engine_object.post_path(id: 3, omg: "pure-awesomeness")
     end
 
     test "[OBJECT] generating application's route" do
@@ -286,7 +286,7 @@ module TestGenerationPrefix
     end
 
     test "[OBJECT] generating application's route includes default_url_options[:script_name]" do
-      RailsApplication.routes.default_url_options = {:script_name => "/something"}
+      RailsApplication.routes.default_url_options = { script_name: "/something" }
       assert_equal "/something/", app_object.root_path
     end
 
@@ -296,11 +296,11 @@ module TestGenerationPrefix
     end
 
     test "[OBJECT] generating engine's route with url_for" do
-      path = engine_object.url_for(:controller => "inside_engine_generating",
-                                   :action => "show",
-                                   :only_path => true,
-                                   :omg => "omg",
-                                   :id => 1)
+      path = engine_object.url_for(controller: "inside_engine_generating",
+                                   action: "show",
+                                   only_path: true,
+                                   omg: "omg",
+                                   id: 1)
       assert_equal "/omg/blog/posts/1", path
     end
 
@@ -308,7 +308,7 @@ module TestGenerationPrefix
       path = engine_object.posts_path
       assert_equal "/awesome/blog/posts", path
 
-      path = engine_object.posts_url(:host => "example.com")
+      path = engine_object.posts_url(host: "example.com")
       assert_equal "http://example.com/awesome/blog/posts", path
     end
 
@@ -316,15 +316,15 @@ module TestGenerationPrefix
       path = engine_object.polymorphic_path(Post.new)
       assert_equal "/awesome/blog/posts/1", path
 
-      path = engine_object.polymorphic_url(Post.new, :host => "www.example.com")
+      path = engine_object.polymorphic_url(Post.new, host: "www.example.com")
       assert_equal "http://www.example.com/awesome/blog/posts/1", path
     end
 
     private
       def verify_redirect(url, status = 301)
-        assert_equal status, last_response.status
-        assert_equal url, last_response.headers["Location"]
-        assert_equal expected_redirect_body(url), last_response.body
+        assert_equal status, response.status
+        assert_equal url, response.headers["Location"]
+        assert_equal expected_redirect_body(url), response.body
       end
 
       def expected_redirect_body(url)
@@ -333,28 +333,26 @@ module TestGenerationPrefix
   end
 
   class EngineMountedAtRoot < ActionDispatch::IntegrationTest
-    include Rack::Test::Methods
-
     class BlogEngine
       def self.routes
         @routes ||= begin
           routes = ActionDispatch::Routing::RouteSet.new
           routes.draw do
-            get "/posts/:id", :to => "posts#show", :as => :post
-
-            get "/relative_path_root",       :to => redirect("")
-            get "/relative_path_redirect",   :to => redirect("foo")
-            get "/relative_option_root",     :to => redirect(:path => "")
-            get "/relative_option_redirect", :to => redirect(:path => "foo")
-            get "/relative_custom_root",     :to => redirect { |params, request| "" }
-            get "/relative_custom_redirect", :to => redirect { |params, request| "foo" }
-
-            get "/absolute_path_root",       :to => redirect("/")
-            get "/absolute_path_redirect",   :to => redirect("/foo")
-            get "/absolute_option_root",     :to => redirect(:path => "/")
-            get "/absolute_option_redirect", :to => redirect(:path => "/foo")
-            get "/absolute_custom_root",     :to => redirect { |params, request| "/" }
-            get "/absolute_custom_redirect", :to => redirect { |params, request| "/foo" }
+            get "/posts/:id", to: "posts#show", as: :post
+
+            get "/relative_path_root",       to: redirect("")
+            get "/relative_path_redirect",   to: redirect("foo")
+            get "/relative_option_root",     to: redirect(path: "")
+            get "/relative_option_redirect", to: redirect(path: "foo")
+            get "/relative_custom_root",     to: redirect { |params, request| "" }
+            get "/relative_custom_redirect", to: redirect { |params, request| "foo" }
+
+            get "/absolute_path_root",       to: redirect("/")
+            get "/absolute_path_redirect",   to: redirect("/foo")
+            get "/absolute_option_root",     to: redirect(path: "/")
+            get "/absolute_option_redirect", to: redirect(path: "/foo")
+            get "/absolute_custom_root",     to: redirect { |params, request| "/" }
+            get "/absolute_custom_redirect", to: redirect { |params, request| "/foo" }
           end
 
           routes
@@ -362,7 +360,7 @@ module TestGenerationPrefix
       end
 
       def self.call(env)
-        env['action_dispatch.routes'] = routes
+        env["action_dispatch.routes"] = routes
         routes.call(env)
       end
     end
@@ -388,74 +386,74 @@ module TestGenerationPrefix
 
     test "generating path inside engine" do
       get "/posts/1"
-      assert_equal "/posts/1", last_response.body
+      assert_equal "/posts/1", response.body
     end
 
     test "[ENGINE] relative path root uses SCRIPT_NAME from request" do
       get "/relative_path_root"
-      verify_redirect "http://example.org/"
+      verify_redirect "http://www.example.com/"
     end
 
     test "[ENGINE] relative path redirect uses SCRIPT_NAME from request" do
       get "/relative_path_redirect"
-      verify_redirect "http://example.org/foo"
+      verify_redirect "http://www.example.com/foo"
     end
 
     test "[ENGINE] relative option root uses SCRIPT_NAME from request" do
       get "/relative_option_root"
-      verify_redirect "http://example.org/"
+      verify_redirect "http://www.example.com/"
     end
 
     test "[ENGINE] relative option redirect uses SCRIPT_NAME from request" do
       get "/relative_option_redirect"
-      verify_redirect "http://example.org/foo"
+      verify_redirect "http://www.example.com/foo"
     end
 
     test "[ENGINE] relative custom root uses SCRIPT_NAME from request" do
       get "/relative_custom_root"
-      verify_redirect "http://example.org/"
+      verify_redirect "http://www.example.com/"
     end
 
     test "[ENGINE] relative custom redirect uses SCRIPT_NAME from request" do
       get "/relative_custom_redirect"
-      verify_redirect "http://example.org/foo"
+      verify_redirect "http://www.example.com/foo"
     end
 
     test "[ENGINE] absolute path root doesn't use SCRIPT_NAME from request" do
       get "/absolute_path_root"
-      verify_redirect "http://example.org/"
+      verify_redirect "http://www.example.com/"
     end
 
     test "[ENGINE] absolute path redirect doesn't use SCRIPT_NAME from request" do
       get "/absolute_path_redirect"
-      verify_redirect "http://example.org/foo"
+      verify_redirect "http://www.example.com/foo"
     end
 
     test "[ENGINE] absolute option root doesn't use SCRIPT_NAME from request" do
       get "/absolute_option_root"
-      verify_redirect "http://example.org/"
+      verify_redirect "http://www.example.com/"
     end
 
     test "[ENGINE] absolute option redirect doesn't use SCRIPT_NAME from request" do
       get "/absolute_option_redirect"
-      verify_redirect "http://example.org/foo"
+      verify_redirect "http://www.example.com/foo"
     end
 
     test "[ENGINE] absolute custom root doesn't use SCRIPT_NAME from request" do
       get "/absolute_custom_root"
-      verify_redirect "http://example.org/"
+      verify_redirect "http://www.example.com/"
     end
 
     test "[ENGINE] absolute custom redirect doesn't use SCRIPT_NAME from request" do
       get "/absolute_custom_redirect"
-      verify_redirect "http://example.org/foo"
+      verify_redirect "http://www.example.com/foo"
     end
 
     private
       def verify_redirect(url, status = 301)
-        assert_equal status, last_response.status
-        assert_equal url, last_response.headers["Location"]
-        assert_equal expected_redirect_body(url), last_response.body
+        assert_equal status, response.status
+        assert_equal url, response.headers["Location"]
+        assert_equal expected_redirect_body(url), response.body
       end
 
       def expected_redirect_body(url)
diff --git a/actionpack/test/dispatch/rack_cache_test.rb b/actionpack/test/dispatch/rack_cache_test.rb
index 79d8a64d29..86b375a2a8 100644
--- a/actionpack/test/dispatch/rack_cache_test.rb
+++ b/actionpack/test/dispatch/rack_cache_test.rb
@@ -1,5 +1,7 @@
-require 'abstract_unit'
-require 'action_dispatch/http/rack_cache'
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "action_dispatch/http/rack_cache"
 
 class RackCacheMetaStoreTest < ActiveSupport::TestCase
   class ReadWriteHash < ::Hash
@@ -12,7 +14,7 @@ class RackCacheMetaStoreTest < ActiveSupport::TestCase
   end
 
   test "stuff is deep duped" do
-    @store.write(:foo, { :bar => :original })
+    @store.write(:foo, bar: :original)
     hash = @store.read(:foo)
     hash[:bar] = :changed
     hash = @store.read(:foo)
diff --git a/actionpack/test/dispatch/reloader_test.rb b/actionpack/test/dispatch/reloader_test.rb
index fe8a4a3a17..e529229fae 100644
--- a/actionpack/test/dispatch/reloader_test.rb
+++ b/actionpack/test/dispatch/reloader_test.rb
@@ -1,32 +1,13 @@
-require 'abstract_unit'
+# frozen_string_literal: true
 
-class ReloaderTest < ActiveSupport::TestCase
-  Reloader = ActionDispatch::Reloader
+require "abstract_unit"
 
+class ReloaderTest < ActiveSupport::TestCase
   teardown do
     ActiveSupport::Reloader.reset_callbacks :prepare
     ActiveSupport::Reloader.reset_callbacks :complete
   end
 
-  def test_prepare_callbacks
-    a = b = c = nil
-    assert_deprecated do
-      Reloader.to_prepare { |*args| a = b = c = 1 }
-      Reloader.to_prepare { |*args| b = c = 2 }
-      Reloader.to_prepare { |*args| c = 3 }
-    end
-
-    # Ensure to_prepare callbacks are not run when defined
-    assert_nil a || b || c
-
-    # Run callbacks
-    call_and_return_body
-
-    assert_equal 1, a
-    assert_equal 2, b
-    assert_equal 3, c
-  end
-
   class MyBody < Array
     def initialize(&block)
       @on_close = block
@@ -45,6 +26,23 @@ class ReloaderTest < ActiveSupport::TestCase
     end
   end
 
+  def test_prepare_callbacks
+    a = b = c = nil
+    reloader.to_prepare { |*args| a = b = c = 1 }
+    reloader.to_prepare { |*args| b = c = 2 }
+    reloader.to_prepare { |*args| c = 3 }
+
+    # Ensure to_prepare callbacks are not run when defined
+    assert_nil a || b || c
+
+    # Run callbacks
+    call_and_return_body
+
+    assert_equal 1, a
+    assert_equal 2, b
+    assert_equal 3, c
+  end
+
   def test_returned_body_object_always_responds_to_close
     body = call_and_return_body
     assert_respond_to body, :close
@@ -62,15 +60,12 @@ class ReloaderTest < ActiveSupport::TestCase
 
   def test_condition_specifies_when_to_reload
     i, j = 0, 0, 0, 0
-    assert_deprecated do
-      Reloader.to_prepare { |*args| i += 1 }
-      Reloader.to_cleanup { |*args| j += 1 }
-    end
 
-    x = Class.new(ActiveSupport::Reloader)
-    x.check = lambda { i < 3 }
+    reloader = reloader(lambda { i < 3 })
+    reloader.to_prepare { |*args| i += 1 }
+    reloader.to_complete { |*args| j += 1 }
 
-    app = Reloader.new(lambda { |env| [200, {}, []] }, x)
+    app = middleware(lambda { |env| [200, {}, []] }, reloader)
     5.times do
       resp = app.call({})
       resp[2].close
@@ -115,24 +110,20 @@ class ReloaderTest < ActiveSupport::TestCase
     assert_respond_to body, :bar
   end
 
-  def test_cleanup_callbacks_are_called_when_body_is_closed
-    cleaned = false
-    assert_deprecated do
-      Reloader.to_cleanup { cleaned = true }
-    end
+  def test_complete_callbacks_are_called_when_body_is_closed
+    completed = false
+    reloader.to_complete { completed = true }
 
     body = call_and_return_body
-    assert !cleaned
+    assert !completed
 
     body.close
-    assert cleaned
+    assert completed
   end
 
   def test_prepare_callbacks_arent_called_when_body_is_closed
     prepared = false
-    assert_deprecated do
-      Reloader.to_prepare { prepared = true }
-    end
+    reloader.to_prepare { prepared = true }
 
     body = call_and_return_body
     prepared = false
@@ -141,45 +132,9 @@ class ReloaderTest < ActiveSupport::TestCase
     assert !prepared
   end
 
-  def test_manual_reloading
-    prepared = cleaned = false
-    assert_deprecated do
-      Reloader.to_prepare { prepared = true }
-      Reloader.to_cleanup { cleaned  = true }
-    end
-
-    assert_deprecated do
-      Reloader.prepare!
-    end
-    assert prepared
-    assert !cleaned
-
-    prepared = cleaned = false
-    assert_deprecated do
-      Reloader.cleanup!
-    end
-    assert prepared
-    assert cleaned
-  end
-
-  def test_prepend_prepare_callback
-    i = 10
-    assert_deprecated do
-      Reloader.to_prepare { i += 1 }
-      Reloader.to_prepare(:prepend => true) { i = 0 }
-    end
-
-    assert_deprecated do
-      Reloader.prepare!
-    end
-    assert_equal 1, i
-  end
-
-  def test_cleanup_callbacks_are_called_on_exceptions
-    cleaned = false
-    assert_deprecated do
-      Reloader.to_cleanup { cleaned  = true }
-    end
+  def test_complete_callbacks_are_called_on_exceptions
+    completed = false
+    reloader.to_complete { completed = true }
 
     begin
       call_and_return_body do
@@ -188,16 +143,25 @@ class ReloaderTest < ActiveSupport::TestCase
     rescue
     end
 
-    assert cleaned
+    assert completed
   end
 
   private
     def call_and_return_body(&block)
-      x = Class.new(ActiveSupport::Reloader)
-      x.check = lambda { true }
+      app = middleware(block || proc { [200, {}, "response"] })
+      _, _, body = app.call("rack.input" => StringIO.new(""))
+      body
+    end
+
+    def middleware(inner_app, reloader = reloader())
+      ActionDispatch::Reloader.new(inner_app, reloader)
+    end
 
-      @response ||= 'response'
-      @reloader ||= Reloader.new(block || proc {[200, {}, @response]}, x)
-      @reloader.call({'rack.input' => StringIO.new('')})[2]
+    def reloader(check = lambda { true })
+      @reloader ||= begin
+                      reloader = Class.new(ActiveSupport::Reloader)
+                      reloader.check = check
+                      reloader
+                    end
     end
 end
diff --git a/actionpack/test/dispatch/request/json_params_parsing_test.rb b/actionpack/test/dispatch/request/json_params_parsing_test.rb
index a07138b55e..beab8e78b5 100644
--- a/actionpack/test/dispatch/request/json_params_parsing_test.rb
+++ b/actionpack/test/dispatch/request/json_params_parsing_test.rb
@@ -1,4 +1,6 @@
-require 'abstract_unit'
+# frozen_string_literal: true
+
+require "abstract_unit"
 
 class JsonParamsParsingTest < ActionDispatch::IntegrationTest
   class TestController < ActionController::Base
@@ -18,44 +20,44 @@ class JsonParamsParsingTest < ActionDispatch::IntegrationTest
 
   test "parses json params for application json" do
     assert_parses(
-      {"person" => {"name" => "David"}},
-      "{\"person\": {\"name\": \"David\"}}", { 'CONTENT_TYPE' => 'application/json' }
+      { "person" => { "name" => "David" } },
+      "{\"person\": {\"name\": \"David\"}}", "CONTENT_TYPE" => "application/json"
     )
   end
 
   test "parses boolean and number json params for application json" do
     assert_parses(
-      {"item" => {"enabled" => false, "count" => 10}},
-      "{\"item\": {\"enabled\": false, \"count\": 10}}", { 'CONTENT_TYPE' => 'application/json' }
+      { "item" => { "enabled" => false, "count" => 10 } },
+      "{\"item\": {\"enabled\": false, \"count\": 10}}", "CONTENT_TYPE" => "application/json"
     )
   end
 
   test "parses json params for application jsonrequest" do
     assert_parses(
-      {"person" => {"name" => "David"}},
-      "{\"person\": {\"name\": \"David\"}}", { 'CONTENT_TYPE' => 'application/jsonrequest' }
+      { "person" => { "name" => "David" } },
+      "{\"person\": {\"name\": \"David\"}}", "CONTENT_TYPE" => "application/jsonrequest"
     )
   end
 
   test "does not parse unregistered media types such as application/vnd.api+json" do
     assert_parses(
       {},
-      "{\"person\": {\"name\": \"David\"}}", { 'CONTENT_TYPE' => 'application/vnd.api+json' }
+      "{\"person\": {\"name\": \"David\"}}", "CONTENT_TYPE" => "application/vnd.api+json"
     )
   end
 
   test "nils are stripped from collections" do
     assert_parses(
-      {"person" => []},
-      "{\"person\":[null]}", { 'CONTENT_TYPE' => 'application/json' }
+      { "person" => [] },
+      "{\"person\":[null]}", "CONTENT_TYPE" => "application/json"
     )
     assert_parses(
-      {"person" => ['foo']},
-      "{\"person\":[\"foo\",null]}", { 'CONTENT_TYPE' => 'application/json' }
+      { "person" => ["foo"] },
+      "{\"person\":[\"foo\",null]}", "CONTENT_TYPE" => "application/json"
     )
     assert_parses(
-      {"person" => []},
-      "{\"person\":[null, null]}", { 'CONTENT_TYPE' => 'application/json' }
+      { "person" => [] },
+      "{\"person\":[null, null]}", "CONTENT_TYPE" => "application/json"
     )
   end
 
@@ -63,7 +65,7 @@ class JsonParamsParsingTest < ActionDispatch::IntegrationTest
     with_test_routing do
       output = StringIO.new
       json = "[\"person]\": {\"name\": \"David\"}}"
-      post "/parse", params: json, headers: { 'CONTENT_TYPE' => 'application/json', 'action_dispatch.show_exceptions' => true, 'action_dispatch.logger' => ActiveSupport::Logger.new(output) }
+      post "/parse", params: json, headers: { "CONTENT_TYPE" => "application/json", "action_dispatch.show_exceptions" => true, "action_dispatch.logger" => ActiveSupport::Logger.new(output) }
       assert_response :bad_request
       output.rewind && err = output.read
       assert err =~ /Error occurred while parsing request parameters/
@@ -75,7 +77,9 @@ class JsonParamsParsingTest < ActionDispatch::IntegrationTest
       begin
         $stderr = StringIO.new # suppress the log
         json = "[\"person]\": {\"name\": \"David\"}}"
-        exception = assert_raise(ActionDispatch::ParamsParser::ParseError) { post "/parse", json, {'CONTENT_TYPE' => 'application/json', 'action_dispatch.show_exceptions' => false} }
+        exception = assert_raise(ActionDispatch::Http::Parameters::ParseError) do
+          post "/parse", params: json, headers: { "CONTENT_TYPE" => "application/json", "action_dispatch.show_exceptions" => false }
+        end
         assert_equal JSON::ParserError, exception.cause.class
         assert_equal exception.cause.message, exception.message
       ensure
@@ -84,9 +88,9 @@ class JsonParamsParsingTest < ActionDispatch::IntegrationTest
     end
   end
 
-  test 'raw_post is not empty for JSON request' do
+  test "raw_post is not empty for JSON request" do
     with_test_routing do
-      post '/parse', params: '{"posts": [{"title": "Post Title"}]}', headers: { 'CONTENT_TYPE' => 'application/json' }
+      post "/parse", params: '{"posts": [{"title": "Post Title"}]}', headers: { "CONTENT_TYPE" => "application/json" }
       assert_equal '{"posts": [{"title": "Post Title"}]}', request.raw_post
     end
   end
@@ -104,7 +108,7 @@ class JsonParamsParsingTest < ActionDispatch::IntegrationTest
       with_routing do |set|
         set.draw do
           ActiveSupport::Deprecation.silence do
-            post ':action', :to => ::JsonParamsParsingTest::TestController
+            post ":action", to: ::JsonParamsParsingTest::TestController
           end
         end
         yield
@@ -114,7 +118,7 @@ end
 
 class RootLessJSONParamsParsingTest < ActionDispatch::IntegrationTest
   class UsersController < ActionController::Base
-    wrap_parameters :format => :json
+    wrap_parameters format: :json
 
     class << self
       attr_accessor :last_request_parameters, :last_parameters
@@ -133,32 +137,32 @@ class RootLessJSONParamsParsingTest < ActionDispatch::IntegrationTest
 
   test "parses json params for application json" do
     assert_parses(
-      {"user" => {"username" => "sikachu"}, "username" => "sikachu"},
-      "{\"username\": \"sikachu\"}", { 'CONTENT_TYPE' => 'application/json' }
+      { "user" => { "username" => "sikachu" }, "username" => "sikachu" },
+      "{\"username\": \"sikachu\"}", "CONTENT_TYPE" => "application/json"
     )
   end
 
   test "parses json params for application jsonrequest" do
     assert_parses(
-      {"user" => {"username" => "sikachu"}, "username" => "sikachu"},
-      "{\"username\": \"sikachu\"}", { 'CONTENT_TYPE' => 'application/jsonrequest' }
+      { "user" => { "username" => "sikachu" }, "username" => "sikachu" },
+      "{\"username\": \"sikachu\"}", "CONTENT_TYPE" => "application/jsonrequest"
     )
   end
 
   test "parses json with non-object JSON content" do
     assert_parses(
-      {"user" => {"_json" => "string content" }, "_json" => "string content" },
-      "\"string content\"", { 'CONTENT_TYPE' => 'application/json' }
+      { "user" => { "_json" => "string content" }, "_json" => "string content" },
+      "\"string content\"", "CONTENT_TYPE" => "application/json"
     )
   end
 
   test "parses json params after custom json mime type registered" do
     begin
       Mime::Type.unregister :json
-      Mime::Type.register "application/json", :json, %w(application/vnd.api+json)
+      Mime::Type.register "application/json", :json, %w(application/vnd.rails+json)
       assert_parses(
-        {"user" => {"username" => "meinac"}, "username" => "meinac"},
-        "{\"username\": \"meinac\"}", { 'CONTENT_TYPE' => 'application/json' }
+        { "user" => { "username" => "meinac" }, "username" => "meinac" },
+        "{\"username\": \"meinac\"}", "CONTENT_TYPE" => "application/json"
       )
     ensure
       Mime::Type.unregister :json
@@ -169,10 +173,10 @@ class RootLessJSONParamsParsingTest < ActionDispatch::IntegrationTest
   test "parses json params after custom json mime type registered with synonym" do
     begin
       Mime::Type.unregister :json
-      Mime::Type.register "application/json", :json, %w(application/vnd.api+json)
+      Mime::Type.register "application/json", :json, %w(application/vnd.rails+json)
       assert_parses(
-        {"user" => {"username" => "meinac"}, "username" => "meinac"},
-        "{\"username\": \"meinac\"}", { 'CONTENT_TYPE' => 'application/vnd.api+json' }
+        { "user" => { "username" => "meinac" }, "username" => "meinac" },
+        "{\"username\": \"meinac\"}", "CONTENT_TYPE" => "application/vnd.rails+json"
       )
     ensure
       Mime::Type.unregister :json
@@ -186,7 +190,7 @@ class RootLessJSONParamsParsingTest < ActionDispatch::IntegrationTest
         post "/parse", params: actual, headers: headers
         assert_response :ok
         assert_equal(expected, UsersController.last_request_parameters)
-        assert_equal(expected.merge({"action" => "parse"}), UsersController.last_parameters)
+        assert_equal(expected.merge("action" => "parse"), UsersController.last_parameters)
       end
     end
 
@@ -194,7 +198,7 @@ class RootLessJSONParamsParsingTest < ActionDispatch::IntegrationTest
       with_routing do |set|
         set.draw do
           ActiveSupport::Deprecation.silence do
-            post ':action', :to => controller
+            post ":action", to: controller
           end
         end
         yield
diff --git a/actionpack/test/dispatch/request/multipart_params_parsing_test.rb b/actionpack/test/dispatch/request/multipart_params_parsing_test.rb
index bab4413b2a..da8233c074 100644
--- a/actionpack/test/dispatch/request/multipart_params_parsing_test.rb
+++ b/actionpack/test/dispatch/request/multipart_params_parsing_test.rb
@@ -1,4 +1,6 @@
-require 'abstract_unit'
+# frozen_string_literal: true
+
+require "abstract_unit"
 
 class MultipartParamsParsingTest < ActionDispatch::IntegrationTest
   class TestController < ActionController::Base
@@ -21,136 +23,136 @@ class MultipartParamsParsingTest < ActionDispatch::IntegrationTest
     end
   end
 
-  FIXTURE_PATH = File.dirname(__FILE__) + '/../../fixtures/multipart'
+  FIXTURE_PATH = File.expand_path("../../fixtures/multipart", __dir__)
 
   def teardown
     TestController.last_request_parameters = nil
   end
 
   test "parses single parameter" do
-    assert_equal({ 'foo' => 'bar' }, parse_multipart('single_parameter'))
+    assert_equal({ "foo" => "bar" }, parse_multipart("single_parameter"))
   end
 
   test "parses bracketed parameters" do
-    assert_equal({ 'foo' => { 'baz' => 'bar'}}, parse_multipart('bracketed_param'))
+    assert_equal({ "foo" => { "baz" => "bar" } }, parse_multipart("bracketed_param"))
   end
 
   test "parse single utf8 parameter" do
-    assert_equal({ 'Iñtërnâtiônàlizætiøn_name' => 'Iñtërnâtiônàlizætiøn_value'},
-                 parse_multipart('single_utf8_param'), "request.request_parameters")
+    assert_equal({ "Iñtërnâtiônàlizætiøn_name" => "Iñtërnâtiônàlizætiøn_value" },
+                 parse_multipart("single_utf8_param"), "request.request_parameters")
     assert_equal(
-      'Iñtërnâtiônàlizætiøn_value',
-      TestController.last_parameters['Iñtërnâtiônàlizætiøn_name'], "request.parameters")
+      "Iñtërnâtiônàlizætiøn_value",
+      TestController.last_parameters["Iñtërnâtiônàlizætiøn_name"], "request.parameters")
   end
 
   test "parse bracketed utf8 parameter" do
-    assert_equal({ 'Iñtërnâtiônàlizætiøn_name' => {
-      'Iñtërnâtiônàlizætiøn_nested_name' => 'Iñtërnâtiônàlizætiøn_value'} },
-      parse_multipart('bracketed_utf8_param'), "request.request_parameters")
+    assert_equal({ "Iñtërnâtiônàlizætiøn_name" => {
+      "Iñtërnâtiônàlizætiøn_nested_name" => "Iñtërnâtiônàlizætiøn_value" } },
+      parse_multipart("bracketed_utf8_param"), "request.request_parameters")
     assert_equal(
-      {'Iñtërnâtiônàlizætiøn_nested_name' => 'Iñtërnâtiônàlizætiøn_value'},
-      TestController.last_parameters['Iñtërnâtiônàlizætiøn_name'], "request.parameters")
+      { "Iñtërnâtiônàlizætiøn_nested_name" => "Iñtërnâtiônàlizætiøn_value" },
+      TestController.last_parameters["Iñtërnâtiônàlizætiøn_name"], "request.parameters")
   end
 
   test "parses text file" do
-    params = parse_multipart('text_file')
+    params = parse_multipart("text_file")
     assert_equal %w(file foo), params.keys.sort
-    assert_equal 'bar', params['foo']
+    assert_equal "bar", params["foo"]
 
-    file = params['file']
-    assert_equal 'file.txt', file.original_filename
+    file = params["file"]
+    assert_equal "file.txt", file.original_filename
     assert_equal "text/plain", file.content_type
-    assert_equal 'contents', file.read
+    assert_equal "contents", file.read
   end
 
   test "parses utf8 filename with percent character" do
-    params = parse_multipart('utf8_filename')
+    params = parse_multipart("utf8_filename")
     assert_equal %w(file foo), params.keys.sort
-    assert_equal 'bar', params['foo']
+    assert_equal "bar", params["foo"]
 
-    file = params['file']
-    assert_equal 'ファイル%名.txt', file.original_filename
+    file = params["file"]
+    assert_equal "ファイル%名.txt", file.original_filename
     assert_equal "text/plain", file.content_type
-    assert_equal 'contents', file.read
+    assert_equal "contents", file.read
   end
 
   test "parses boundary problem file" do
-    params = parse_multipart('boundary_problem_file')
+    params = parse_multipart("boundary_problem_file")
     assert_equal %w(file foo), params.keys.sort
 
-    file = params['file']
-    foo  = params['foo']
+    file = params["file"]
+    foo  = params["foo"]
 
-    assert_equal 'file.txt', file.original_filename
+    assert_equal "file.txt", file.original_filename
     assert_equal "text/plain", file.content_type
 
-    assert_equal 'bar', foo
+    assert_equal "bar", foo
   end
 
   test "parses large text file" do
-    params = parse_multipart('large_text_file')
+    params = parse_multipart("large_text_file")
     assert_equal %w(file foo), params.keys.sort
-    assert_equal 'bar', params['foo']
+    assert_equal "bar", params["foo"]
 
-    file = params['file']
+    file = params["file"]
 
-    assert_equal 'file.txt', file.original_filename
+    assert_equal "file.txt", file.original_filename
     assert_equal "text/plain", file.content_type
-    assert_equal(('a' * 20480), file.read)
+    assert_equal(("a" * 20480), file.read)
   end
 
   test "parses binary file" do
-    params = parse_multipart('binary_file')
+    params = parse_multipart("binary_file")
     assert_equal %w(file flowers foo), params.keys.sort
-    assert_equal 'bar', params['foo']
+    assert_equal "bar", params["foo"]
 
-    file = params['file']
-    assert_equal 'file.csv', file.original_filename
+    file = params["file"]
+    assert_equal "file.csv", file.original_filename
     assert_nil file.content_type
-    assert_equal 'contents', file.read
+    assert_equal "contents", file.read
 
-    file = params['flowers']
-    assert_equal 'flowers.jpg', file.original_filename
+    file = params["flowers"]
+    assert_equal "flowers.jpg", file.original_filename
     assert_equal "image/jpeg", file.content_type
     assert_equal 19512, file.size
   end
 
   test "parses mixed files" do
-    params = parse_multipart('mixed_files')
+    params = parse_multipart("mixed_files")
     assert_equal %w(files foo), params.keys.sort
-    assert_equal 'bar', params['foo']
+    assert_equal "bar", params["foo"]
 
     # Rack doesn't handle multipart/mixed for us.
-    files = params['files']
+    files = params["files"]
     assert_equal 19756, files.bytesize
   end
 
   test "does not create tempfile if no file has been selected" do
-    params = parse_multipart('none')
+    params = parse_multipart("none")
     assert_equal %w(submit-name), params.keys.sort
-    assert_equal 'Larry', params['submit-name']
-    assert_equal nil, params['files']
+    assert_equal "Larry", params["submit-name"]
+    assert_nil params["files"]
   end
 
   test "parses empty upload file" do
-    params = parse_multipart('empty')
+    params = parse_multipart("empty")
     assert_equal %w(files submit-name), params.keys.sort
-    assert_equal 'Larry', params['submit-name']
-    assert params['files']
-    assert_equal "", params['files'].read
+    assert_equal "Larry", params["submit-name"]
+    assert params["files"]
+    assert_equal "", params["files"].read
   end
 
   test "uploads and reads binary file" do
     with_test_routing do
-      fixture = FIXTURE_PATH + "/mona_lisa.jpg"
-      params = { :uploaded_data => fixture_file_upload(fixture, "image/jpg") }
-      post '/read', params: params
+      fixture = FIXTURE_PATH + "/ruby_on_rails.jpg"
+      params = { uploaded_data: fixture_file_upload(fixture, "image/jpg") }
+      post "/read", params: params
     end
   end
 
   test "uploads and reads file" do
     with_test_routing do
-      post '/read', params: { uploaded_data: fixture_file_upload(FIXTURE_PATH + "/hello.txt", "text/plain") }
+      post "/read", params: { uploaded_data: fixture_file_upload(FIXTURE_PATH + "/hello.txt", "text/plain") }
       assert_equal "File: Hello", response.body
     end
   end
@@ -160,7 +162,7 @@ class MultipartParamsParsingTest < ActionDispatch::IntegrationTest
     with_routing do |set|
       set.draw do
         ActiveSupport::Deprecation.silence do
-          get ':action', controller: 'multipart_params_parsing_test/test'
+          get ":action", controller: "multipart_params_parsing_test/test"
         end
       end
       headers = { "CONTENT_TYPE" => "multipart/form-data; boundary=AaB03x" }
@@ -171,7 +173,7 @@ class MultipartParamsParsingTest < ActionDispatch::IntegrationTest
 
   private
     def fixture(name)
-      File.open(File.join(FIXTURE_PATH, name), 'rb') do |file|
+      File.open(File.join(FIXTURE_PATH, name), "rb") do |file|
         { "rack.input" => file.read,
           "CONTENT_TYPE" => "multipart/form-data; boundary=AaB03x",
           "CONTENT_LENGTH" => file.stat.size.to_s }
@@ -191,7 +193,7 @@ class MultipartParamsParsingTest < ActionDispatch::IntegrationTest
       with_routing do |set|
         set.draw do
           ActiveSupport::Deprecation.silence do
-            post ':action', :controller => 'multipart_params_parsing_test/test'
+            post ":action", controller: "multipart_params_parsing_test/test"
           end
         end
         yield
diff --git a/actionpack/test/dispatch/request/query_string_parsing_test.rb b/actionpack/test/dispatch/request/query_string_parsing_test.rb
index f04022a544..f9ae5ef4e8 100644
--- a/actionpack/test/dispatch/request/query_string_parsing_test.rb
+++ b/actionpack/test/dispatch/request/query_string_parsing_test.rb
@@ -1,4 +1,6 @@
-require 'abstract_unit'
+# frozen_string_literal: true
+
+require "abstract_unit"
 
 class QueryStringParsingTest < ActionDispatch::IntegrationTest
   class TestController < ActionController::Base
@@ -29,92 +31,92 @@ class QueryStringParsingTest < ActionDispatch::IntegrationTest
 
   test "query string" do
     assert_parses(
-      {"action" => "create_customer", "full_name" => "David Heinemeier Hansson", "customerId" => "1"},
+      { "action" => "create_customer", "full_name" => "David Heinemeier Hansson", "customerId" => "1" },
       "action=create_customer&full_name=David%20Heinemeier%20Hansson&customerId=1"
     )
   end
 
   test "deep query string" do
     assert_parses(
-      {'x' => {'y' => {'z' => '10'}}},
+      { "x" => { "y" => { "z" => "10" } } },
       "x[y][z]=10"
     )
   end
 
   test "deep query string with array" do
-    assert_parses({'x' => {'y' => {'z' => ['10']}}}, 'x[y][z][]=10')
-    assert_parses({'x' => {'y' => {'z' => ['10', '5']}}}, 'x[y][z][]=10&x[y][z][]=5')
+    assert_parses({ "x" => { "y" => { "z" => ["10"] } } }, "x[y][z][]=10")
+    assert_parses({ "x" => { "y" => { "z" => ["10", "5"] } } }, "x[y][z][]=10&x[y][z][]=5")
   end
 
   test "deep query string with array of hash" do
-    assert_parses({'x' => {'y' => [{'z' => '10'}]}}, 'x[y][][z]=10')
-    assert_parses({'x' => {'y' => [{'z' => '10', 'w' => '10'}]}}, 'x[y][][z]=10&x[y][][w]=10')
-    assert_parses({'x' => {'y' => [{'z' => '10', 'v' => {'w' => '10'}}]}}, 'x[y][][z]=10&x[y][][v][w]=10')
+    assert_parses({ "x" => { "y" => [{ "z" => "10" }] } }, "x[y][][z]=10")
+    assert_parses({ "x" => { "y" => [{ "z" => "10", "w" => "10" }] } }, "x[y][][z]=10&x[y][][w]=10")
+    assert_parses({ "x" => { "y" => [{ "z" => "10", "v" => { "w" => "10" } }] } }, "x[y][][z]=10&x[y][][v][w]=10")
   end
 
   test "deep query string with array of hashes with one pair" do
-    assert_parses({'x' => {'y' => [{'z' => '10'}, {'z' => '20'}]}}, 'x[y][][z]=10&x[y][][z]=20')
+    assert_parses({ "x" => { "y" => [{ "z" => "10" }, { "z" => "20" }] } }, "x[y][][z]=10&x[y][][z]=20")
   end
 
   test "deep query string with array of hashes with multiple pairs" do
     assert_parses(
-      {'x' => {'y' => [{'z' => '10', 'w' => 'a'}, {'z' => '20', 'w' => 'b'}]}},
-      'x[y][][z]=10&x[y][][w]=a&x[y][][z]=20&x[y][][w]=b'
+      { "x" => { "y" => [{ "z" => "10", "w" => "a" }, { "z" => "20", "w" => "b" }] } },
+      "x[y][][z]=10&x[y][][w]=a&x[y][][z]=20&x[y][][w]=b"
     )
   end
 
   test "query string with nil" do
     assert_parses(
-      { "action" => "create_customer", "full_name" => ''},
+      { "action" => "create_customer", "full_name" => "" },
       "action=create_customer&full_name="
     )
   end
 
   test "query string with array" do
     assert_parses(
-      { "action" => "create_customer", "selected" => ["1", "2", "3"]},
+      { "action" => "create_customer", "selected" => ["1", "2", "3"] },
       "action=create_customer&selected[]=1&selected[]=2&selected[]=3"
     )
   end
 
   test "query string with amps" do
     assert_parses(
-      { "action" => "create_customer", "name" => "Don't & Does"},
+      { "action" => "create_customer", "name" => "Don't & Does" },
       "action=create_customer&name=Don%27t+%26+Does"
     )
   end
 
   test "query string with many equal" do
     assert_parses(
-      { "action" => "create_customer", "full_name" => "abc=def=ghi"},
+      { "action" => "create_customer", "full_name" => "abc=def=ghi" },
       "action=create_customer&full_name=abc=def=ghi"
     )
   end
 
   test "query string without equal" do
-    assert_parses({"action" => nil}, "action")
-    assert_parses({"action" => {"foo" => nil}}, "action[foo]")
-    assert_parses({"action" => {"foo" => { "bar" => nil }}}, "action[foo][bar]")
-    assert_parses({"action" => {"foo" => { "bar" => [] }}}, "action[foo][bar][]")
-    assert_parses({"action" => {"foo" => [] }}, "action[foo][]")
-    assert_parses({"action"=>{"foo"=>[{"bar"=>nil}]}}, "action[foo][][bar]")
+    assert_parses({ "action" => nil }, "action")
+    assert_parses({ "action" => { "foo" => nil } }, "action[foo]")
+    assert_parses({ "action" => { "foo" => { "bar" => nil } } }, "action[foo][bar]")
+    assert_parses({ "action" => { "foo" => { "bar" => [] } } }, "action[foo][bar][]")
+    assert_parses({ "action" => { "foo" => [] } }, "action[foo][]")
+    assert_parses({ "action" => { "foo" => [{ "bar" => nil }] } }, "action[foo][][bar]")
   end
 
   def test_array_parses_without_nil
-    assert_parses({"action" => ['1']}, "action[]=1&action[]")
+    assert_parses({ "action" => ["1"] }, "action[]=1&action[]")
   end
 
   test "perform_deep_munge" do
     old_perform_deep_munge = ActionDispatch::Request::Utils.perform_deep_munge
     ActionDispatch::Request::Utils.perform_deep_munge = false
     begin
-      assert_parses({"action" => nil}, "action")
-      assert_parses({"action" => {"foo" => nil}}, "action[foo]")
-      assert_parses({"action" => {"foo" => {"bar" => nil}}}, "action[foo][bar]")
-      assert_parses({"action" => {"foo" => {"bar" => [nil]}}}, "action[foo][bar][]")
-      assert_parses({"action" => {"foo" => [nil]}}, "action[foo][]")
-      assert_parses({"action" => {"foo" => [{"bar" => nil}]}}, "action[foo][][bar]")
-      assert_parses({"action" => ['1',nil]}, "action[]=1&action[]")
+      assert_parses({ "action" => nil }, "action")
+      assert_parses({ "action" => { "foo" => nil } }, "action[foo]")
+      assert_parses({ "action" => { "foo" => { "bar" => nil } } }, "action[foo][bar]")
+      assert_parses({ "action" => { "foo" => { "bar" => [nil] } } }, "action[foo][bar][]")
+      assert_parses({ "action" => { "foo" => [nil] } }, "action[foo][]")
+      assert_parses({ "action" => { "foo" => [{ "bar" => nil }] } }, "action[foo][][bar]")
+      assert_parses({ "action" => ["1", nil] }, "action[]=1&action[]")
     ensure
       ActionDispatch::Request::Utils.perform_deep_munge = old_perform_deep_munge
     end
@@ -129,14 +131,14 @@ class QueryStringParsingTest < ActionDispatch::IntegrationTest
 
   test "query string with many ampersands" do
     assert_parses(
-      { "action" => "create_customer", "full_name" => "David Heinemeier Hansson"},
+      { "action" => "create_customer", "full_name" => "David Heinemeier Hansson" },
       "&action=create_customer&&&full_name=David%20Heinemeier%20Hansson"
     )
   end
 
   test "unbalanced query string with array" do
     assert_parses(
-      {'location' => ["1", "2"], 'age_group' => ["2"]},
+      { "location" => ["1", "2"], "age_group" => ["2"] },
       "location[]=1&location[]=2&age_group[]=2"
     )
   end
@@ -145,7 +147,7 @@ class QueryStringParsingTest < ActionDispatch::IntegrationTest
     with_routing do |set|
       set.draw do
         ActiveSupport::Deprecation.silence do
-          get ':action', :to => ::QueryStringParsingTest::TestController
+          get ":action", to: ::QueryStringParsingTest::TestController
         end
       end
 
@@ -159,7 +161,7 @@ class QueryStringParsingTest < ActionDispatch::IntegrationTest
       with_routing do |set|
         set.draw do
           ActiveSupport::Deprecation.silence do
-            get ':action', :to => ::QueryStringParsingTest::TestController
+            get ":action", to: ::QueryStringParsingTest::TestController
           end
         end
         @app = self.class.build_app(set) do |middleware|
diff --git a/actionpack/test/dispatch/request/session_test.rb b/actionpack/test/dispatch/request/session_test.rb
index e022e7e21e..7b6ce31f29 100644
--- a/actionpack/test/dispatch/request/session_test.rb
+++ b/actionpack/test/dispatch/request/session_test.rb
@@ -1,5 +1,7 @@
-require 'abstract_unit'
-require 'action_dispatch/middleware/session/abstract_store'
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "action_dispatch/middleware/session/abstract_store"
 
 module ActionDispatch
   class Request
@@ -17,18 +19,18 @@ module ActionDispatch
 
       def test_to_hash
         s = Session.create(store, req, {})
-        s['foo'] = 'bar'
-        assert_equal 'bar', s['foo']
-        assert_equal({'foo' => 'bar'}, s.to_hash)
+        s["foo"] = "bar"
+        assert_equal "bar", s["foo"]
+        assert_equal({ "foo" => "bar" }, s.to_hash)
       end
 
       def test_create_merges_old
         s = Session.create(store, req, {})
-        s['foo'] = 'bar'
+        s["foo"] = "bar"
 
         s1 = Session.create(store, req, {})
         assert_not_equal s, s1
-        assert_equal 'bar', s1['foo']
+        assert_equal "bar", s1["foo"]
       end
 
       def test_find
@@ -40,7 +42,7 @@ module ActionDispatch
 
       def test_destroy
         s = Session.create(store, req, {})
-        s['rails'] = 'ftw'
+        s["rails"] = "ftw"
 
         s.destroy
 
@@ -49,22 +51,32 @@ module ActionDispatch
 
       def test_keys
         s = Session.create(store, req, {})
-        s['rails'] = 'ftw'
-        s['adequate'] = 'awesome'
+        s["rails"] = "ftw"
+        s["adequate"] = "awesome"
         assert_equal %w[rails adequate], s.keys
       end
 
+      def test_keys_with_deferred_loading
+        s = Session.create(store_with_data, req, {})
+        assert_equal %w[sample_key], s.keys
+      end
+
       def test_values
         s = Session.create(store, req, {})
-        s['rails'] = 'ftw'
-        s['adequate'] = 'awesome'
+        s["rails"] = "ftw"
+        s["adequate"] = "awesome"
         assert_equal %w[ftw awesome], s.values
       end
 
+      def test_values_with_deferred_loading
+        s = Session.create(store_with_data, req, {})
+        assert_equal %w[sample_value], s.values
+      end
+
       def test_clear
         s = Session.create(store, req, {})
-        s['rails'] = 'ftw'
-        s['adequate'] = 'awesome'
+        s["rails"] = "ftw"
+        s["adequate"] = "awesome"
 
         s.clear
         assert_empty(s.values)
@@ -72,19 +84,19 @@ module ActionDispatch
 
       def test_update
         s = Session.create(store, req, {})
-        s['rails'] = 'ftw'
+        s["rails"] = "ftw"
 
-        s.update(:rails => 'awesome')
+        s.update(rails: "awesome")
 
-        assert_equal(['rails'], s.keys)
-        assert_equal('awesome', s['rails'])
+        assert_equal(["rails"], s.keys)
+        assert_equal("awesome", s["rails"])
       end
 
       def test_delete
         s = Session.create(store, req, {})
-        s['rails'] = 'ftw'
+        s["rails"] = "ftw"
 
-        s.delete('rails')
+        s.delete("rails")
 
         assert_empty(s.keys)
       end
@@ -92,13 +104,13 @@ module ActionDispatch
       def test_fetch
         session = Session.create(store, req, {})
 
-        session['one'] = '1'
-        assert_equal '1', session.fetch(:one)
+        session["one"] = "1"
+        assert_equal "1", session.fetch(:one)
 
-        assert_equal '2', session.fetch(:two, '2')
+        assert_equal "2", session.fetch(:two, "2")
         assert_nil session.fetch(:two, nil)
 
-        assert_equal 'three', session.fetch(:three) {|el| el.to_s }
+        assert_equal "three", session.fetch(:three) { |el| el.to_s }
 
         assert_raise KeyError do
           session.fetch(:three)
@@ -106,27 +118,35 @@ module ActionDispatch
       end
 
       private
-      def store
-        Class.new {
-          def load_session(env); [1, {}]; end
-          def session_exists?(env); true; end
-          def delete_session(env, id, options); 123; end
-        }.new
-      end
+        def store
+          Class.new {
+            def load_session(env); [1, {}]; end
+            def session_exists?(env); true; end
+            def delete_session(env, id, options); 123; end
+          }.new
+        end
+
+        def store_with_data
+          Class.new {
+            def load_session(env); [1, { "sample_key" => "sample_value" }]; end
+            def session_exists?(env); true; end
+            def delete_session(env, id, options); 123; end
+          }.new
+        end
     end
 
     class SessionIntegrationTest < ActionDispatch::IntegrationTest
       class MySessionApp
         def call(env)
           request = Rack::Request.new(env)
-          request.session['hello'] = 'Hello from MySessionApp!'
-          [ 200, {}, ['Hello from MySessionApp!'] ]
+          request.session["hello"] = "Hello from MySessionApp!"
+          [ 200, {}, ["Hello from MySessionApp!"] ]
         end
       end
 
       Router = ActionDispatch::Routing::RouteSet.new
       Router.draw do
-        get '/mysessionapp' => MySessionApp.new
+        get "/mysessionapp" => MySessionApp.new
       end
 
       def app
@@ -134,10 +154,10 @@ module ActionDispatch
       end
 
       def test_session_follows_rack_api_contract_1
-        get '/mysessionapp'
+        get "/mysessionapp"
         assert_response :ok
-        assert_equal 'Hello from MySessionApp!', @response.body
-        assert_equal 'Hello from MySessionApp!', session['hello']
+        assert_equal "Hello from MySessionApp!", @response.body
+        assert_equal "Hello from MySessionApp!", session["hello"]
       end
     end
   end
diff --git a/actionpack/test/dispatch/request/url_encoded_params_parsing_test.rb b/actionpack/test/dispatch/request/url_encoded_params_parsing_test.rb
index b9f8c52378..9e55a7242e 100644
--- a/actionpack/test/dispatch/request/url_encoded_params_parsing_test.rb
+++ b/actionpack/test/dispatch/request/url_encoded_params_parsing_test.rb
@@ -1,4 +1,6 @@
-require 'abstract_unit'
+# frozen_string_literal: true
+
+require "abstract_unit"
 
 class UrlEncodedParamsParsingTest < ActionDispatch::IntegrationTest
   class TestController < ActionController::Base
@@ -18,7 +20,7 @@ class UrlEncodedParamsParsingTest < ActionDispatch::IntegrationTest
 
   test "parses unbalanced query string with array" do
     query    = "location[]=1&location[]=2&age_group[]=2"
-    expected = { 'location' => ["1", "2"], 'age_group' => ["2"] }
+    expected = { "location" => ["1", "2"], "age_group" => ["2"] }
     assert_parses expected, query
   end
 
@@ -55,7 +57,7 @@ class UrlEncodedParamsParsingTest < ActionDispatch::IntegrationTest
       "products[second]=Pc",
       "=Save"
     ].join("&")
-    expected =  {
+    expected = {
       "customers" => {
         "boston" => {
           "first" => {
@@ -107,7 +109,7 @@ class UrlEncodedParamsParsingTest < ActionDispatch::IntegrationTest
     query = [
       "customers[boston][first][name]=David",
       "something_else=blah",
-      "logo=#{File.expand_path(__FILE__)}"
+      "logo=#{__FILE__}"
     ].join("&")
     expected = {
       "customers" => {
@@ -118,7 +120,7 @@ class UrlEncodedParamsParsingTest < ActionDispatch::IntegrationTest
         }
       },
       "something_else" => "blah",
-      "logo" => File.expand_path(__FILE__),
+      "logo" => __FILE__,
     }
     assert_parses expected, query
   end
@@ -141,7 +143,7 @@ class UrlEncodedParamsParsingTest < ActionDispatch::IntegrationTest
       with_routing do |set|
         set.draw do
           ActiveSupport::Deprecation.silence do
-            post ':action', to: ::UrlEncodedParamsParsingTest::TestController
+            post ":action", to: ::UrlEncodedParamsParsingTest::TestController
           end
         end
         yield
diff --git a/actionpack/test/dispatch/request_id_test.rb b/actionpack/test/dispatch/request_id_test.rb
index 00d8caf8f4..aa3175c986 100644
--- a/actionpack/test/dispatch/request_id_test.rb
+++ b/actionpack/test/dispatch/request_id_test.rb
@@ -1,16 +1,18 @@
-require 'abstract_unit'
+# frozen_string_literal: true
+
+require "abstract_unit"
 
 class RequestIdTest < ActiveSupport::TestCase
   test "passing on the request id from the outside" do
-    assert_equal "external-uu-rid", stub_request('HTTP_X_REQUEST_ID' => 'external-uu-rid').request_id
+    assert_equal "external-uu-rid", stub_request("HTTP_X_REQUEST_ID" => "external-uu-rid").request_id
   end
 
   test "ensure that only alphanumeric uurids are accepted" do
-    assert_equal "X-Hacked-HeaderStuff", stub_request('HTTP_X_REQUEST_ID' => '; X-Hacked-Header: Stuff').request_id
+    assert_equal "X-Hacked-HeaderStuff", stub_request("HTTP_X_REQUEST_ID" => "; X-Hacked-Header: Stuff").request_id
   end
 
   test "ensure that 255 char limit on the request id is being enforced" do
-    assert_equal "X" * 255, stub_request('HTTP_X_REQUEST_ID' => 'X' * 500).request_id
+    assert_equal "X" * 255, stub_request("HTTP_X_REQUEST_ID" => "X" * 500).request_id
   end
 
   test "generating a request id when none is supplied" do
@@ -18,15 +20,15 @@ class RequestIdTest < ActiveSupport::TestCase
   end
 
   test "uuid alias" do
-    assert_equal "external-uu-rid", stub_request('HTTP_X_REQUEST_ID' => 'external-uu-rid').uuid
+    assert_equal "external-uu-rid", stub_request("HTTP_X_REQUEST_ID" => "external-uu-rid").uuid
   end
 
   private
 
-  def stub_request(env = {})
-    ActionDispatch::RequestId.new(lambda { |environment| [ 200, environment, [] ] }).call(env)
-    ActionDispatch::Request.new(env)
-  end
+    def stub_request(env = {})
+      ActionDispatch::RequestId.new(lambda { |environment| [ 200, environment, [] ] }).call(env)
+      ActionDispatch::Request.new(env)
+    end
 end
 
 class RequestIdResponseTest < ActionDispatch::IntegrationTest
@@ -38,32 +40,31 @@ class RequestIdResponseTest < ActionDispatch::IntegrationTest
 
   test "request id is passed all the way to the response" do
     with_test_route_set do
-      get '/'
+      get "/"
       assert_match(/\w+/, @response.headers["X-Request-Id"])
     end
   end
 
   test "request id given on request is passed all the way to the response" do
     with_test_route_set do
-      get '/', headers: { 'HTTP_X_REQUEST_ID' => 'X' * 500 }
+      get "/", headers: { "HTTP_X_REQUEST_ID" => "X" * 500 }
       assert_equal "X" * 255, @response.headers["X-Request-Id"]
     end
   end
 
-
   private
 
-  def with_test_route_set
-    with_routing do |set|
-      set.draw do
-        get '/', :to => ::RequestIdResponseTest::TestController.action(:index)
-      end
+    def with_test_route_set
+      with_routing do |set|
+        set.draw do
+          get "/", to: ::RequestIdResponseTest::TestController.action(:index)
+        end
 
-      @app = self.class.build_app(set) do |middleware|
-        middleware.use ActionDispatch::RequestId
-      end
+        @app = self.class.build_app(set) do |middleware|
+          middleware.use ActionDispatch::RequestId
+        end
 
-      yield
+        yield
+      end
     end
-  end
 end
diff --git a/actionpack/test/dispatch/request_test.rb b/actionpack/test/dispatch/request_test.rb
index 8a5d85ab84..8661dc56d6 100644
--- a/actionpack/test/dispatch/request_test.rb
+++ b/actionpack/test/dispatch/request_test.rb
@@ -1,4 +1,6 @@
-require 'abstract_unit'
+# frozen_string_literal: true
+
+require "abstract_unit"
 
 class BaseRequestTest < ActiveSupport::TestCase
   def setup
@@ -14,15 +16,15 @@ class BaseRequestTest < ActiveSupport::TestCase
   end
 
   def url_for(options = {})
-    options = { host: 'www.example.com' }.merge!(options)
+    options = { host: "www.example.com" }.merge!(options)
     ActionDispatch::Http::URL.url_for(options)
   end
 
-  protected
+  private
     def stub_request(env = {})
       ip_spoofing_check = env.key?(:ip_spoofing_check) ? env.delete(:ip_spoofing_check) : true
       @trusted_proxies ||= nil
-      ip_app = ActionDispatch::RemoteIp.new(Proc.new { }, ip_spoofing_check, @trusted_proxies)
+      ip_app = ActionDispatch::RemoteIp.new(Proc.new {}, ip_spoofing_check, @trusted_proxies)
       ActionDispatch::Http::URL.tld_length = env.delete(:tld_length) if env.key?(:tld_length)
 
       ip_app.call(env)
@@ -34,141 +36,141 @@ end
 
 class RequestUrlFor < BaseRequestTest
   test "url_for class method" do
-    e = assert_raise(ArgumentError) { url_for(:host => nil) }
+    e = assert_raise(ArgumentError) { url_for(host: nil) }
     assert_match(/Please provide the :host parameter/, e.message)
 
-    assert_equal '/books', url_for(:only_path => true, :path => '/books')
-
-    assert_equal 'http://www.example.com/books/?q=code', url_for(trailing_slash: true, path: '/books?q=code')
-    assert_equal 'http://www.example.com/books/?spareslashes=////', url_for(trailing_slash: true, path: '/books?spareslashes=////')
-
-    assert_equal 'http://www.example.com',  url_for
-    assert_equal 'http://api.example.com',  url_for(:subdomain => 'api')
-    assert_equal 'http://example.com',      url_for(:subdomain => false)
-    assert_equal 'http://www.ror.com',      url_for(:domain => 'ror.com')
-    assert_equal 'http://api.ror.co.uk',    url_for(:host => 'www.ror.co.uk', :subdomain => 'api', :tld_length => 2)
-    assert_equal 'http://www.example.com:8080',   url_for(:port => 8080)
-    assert_equal 'https://www.example.com',       url_for(:protocol => 'https')
-    assert_equal 'http://www.example.com/docs',   url_for(:path => '/docs')
-    assert_equal 'http://www.example.com#signup', url_for(:anchor => 'signup')
-    assert_equal 'http://www.example.com/',       url_for(:trailing_slash => true)
-    assert_equal 'http://dhh:supersecret@www.example.com', url_for(:user => 'dhh', :password => 'supersecret')
-    assert_equal 'http://www.example.com?search=books',    url_for(:params => { :search => 'books' })
-    assert_equal 'http://www.example.com?params=',  url_for(:params => '')
-    assert_equal 'http://www.example.com?params=1', url_for(:params => 1)
+    assert_equal "/books", url_for(only_path: true, path: "/books")
+
+    assert_equal "http://www.example.com/books/?q=code", url_for(trailing_slash: true, path: "/books?q=code")
+    assert_equal "http://www.example.com/books/?spareslashes=////", url_for(trailing_slash: true, path: "/books?spareslashes=////")
+
+    assert_equal "http://www.example.com",  url_for
+    assert_equal "http://api.example.com",  url_for(subdomain: "api")
+    assert_equal "http://example.com",      url_for(subdomain: false)
+    assert_equal "http://www.ror.com",      url_for(domain: "ror.com")
+    assert_equal "http://api.ror.co.uk",    url_for(host: "www.ror.co.uk", subdomain: "api", tld_length: 2)
+    assert_equal "http://www.example.com:8080",   url_for(port: 8080)
+    assert_equal "https://www.example.com",       url_for(protocol: "https")
+    assert_equal "http://www.example.com/docs",   url_for(path: "/docs")
+    assert_equal "http://www.example.com#signup", url_for(anchor: "signup")
+    assert_equal "http://www.example.com/",       url_for(trailing_slash: true)
+    assert_equal "http://dhh:supersecret@www.example.com", url_for(user: "dhh", password: "supersecret")
+    assert_equal "http://www.example.com?search=books",    url_for(params: { search: "books" })
+    assert_equal "http://www.example.com?params=",  url_for(params: "")
+    assert_equal "http://www.example.com?params=1", url_for(params: 1)
   end
 end
 
 class RequestIP < BaseRequestTest
   test "remote ip" do
-    request = stub_request 'REMOTE_ADDR' => '1.2.3.4'
-    assert_equal '1.2.3.4', request.remote_ip
+    request = stub_request "REMOTE_ADDR" => "1.2.3.4"
+    assert_equal "1.2.3.4", request.remote_ip
 
-    request = stub_request 'REMOTE_ADDR' => '1.2.3.4,3.4.5.6'
-    assert_equal '3.4.5.6', request.remote_ip
+    request = stub_request "REMOTE_ADDR" => "1.2.3.4,3.4.5.6"
+    assert_equal "3.4.5.6", request.remote_ip
 
-    request = stub_request 'REMOTE_ADDR' => '1.2.3.4',
-                           'HTTP_X_FORWARDED_FOR' => '3.4.5.6'
-    assert_equal '3.4.5.6', request.remote_ip
+    request = stub_request "REMOTE_ADDR" => "1.2.3.4",
+                           "HTTP_X_FORWARDED_FOR" => "3.4.5.6"
+    assert_equal "3.4.5.6", request.remote_ip
 
-    request = stub_request 'REMOTE_ADDR' => '127.0.0.1',
-                           'HTTP_X_FORWARDED_FOR' => '3.4.5.6'
-    assert_equal '3.4.5.6', request.remote_ip
+    request = stub_request "REMOTE_ADDR" => "127.0.0.1",
+                           "HTTP_X_FORWARDED_FOR" => "3.4.5.6"
+    assert_equal "3.4.5.6", request.remote_ip
 
-    request = stub_request 'HTTP_X_FORWARDED_FOR' => '3.4.5.6,unknown'
-    assert_equal '3.4.5.6', request.remote_ip
+    request = stub_request "HTTP_X_FORWARDED_FOR" => "3.4.5.6,unknown"
+    assert_equal "3.4.5.6", request.remote_ip
 
-    request = stub_request 'HTTP_X_FORWARDED_FOR' => '3.4.5.6,172.16.0.1'
-    assert_equal '3.4.5.6', request.remote_ip
+    request = stub_request "HTTP_X_FORWARDED_FOR" => "3.4.5.6,172.16.0.1"
+    assert_equal "3.4.5.6", request.remote_ip
 
-    request = stub_request 'HTTP_X_FORWARDED_FOR' => '3.4.5.6,192.168.0.1'
-    assert_equal '3.4.5.6', request.remote_ip
+    request = stub_request "HTTP_X_FORWARDED_FOR" => "3.4.5.6,192.168.0.1"
+    assert_equal "3.4.5.6", request.remote_ip
 
-    request = stub_request 'HTTP_X_FORWARDED_FOR' => '3.4.5.6,10.0.0.1'
-    assert_equal '3.4.5.6', request.remote_ip
+    request = stub_request "HTTP_X_FORWARDED_FOR" => "3.4.5.6,10.0.0.1"
+    assert_equal "3.4.5.6", request.remote_ip
 
-    request = stub_request 'HTTP_X_FORWARDED_FOR' => '3.4.5.6, 10.0.0.1, 10.0.0.1'
-    assert_equal '3.4.5.6', request.remote_ip
+    request = stub_request "HTTP_X_FORWARDED_FOR" => "3.4.5.6, 10.0.0.1, 10.0.0.1"
+    assert_equal "3.4.5.6", request.remote_ip
 
-    request = stub_request 'HTTP_X_FORWARDED_FOR' => '3.4.5.6,127.0.0.1'
-    assert_equal '3.4.5.6', request.remote_ip
+    request = stub_request "HTTP_X_FORWARDED_FOR" => "3.4.5.6,127.0.0.1"
+    assert_equal "3.4.5.6", request.remote_ip
 
-    request = stub_request 'HTTP_X_FORWARDED_FOR' => 'unknown,192.168.0.1'
-    assert_equal nil, request.remote_ip
+    request = stub_request "HTTP_X_FORWARDED_FOR" => "unknown,192.168.0.1"
+    assert_nil request.remote_ip
 
-    request = stub_request 'HTTP_X_FORWARDED_FOR' => '9.9.9.9, 3.4.5.6, 172.31.4.4, 10.0.0.1'
-    assert_equal '3.4.5.6', request.remote_ip
+    request = stub_request "HTTP_X_FORWARDED_FOR" => "9.9.9.9, 3.4.5.6, 172.31.4.4, 10.0.0.1"
+    assert_equal "3.4.5.6", request.remote_ip
 
-    request = stub_request 'HTTP_X_FORWARDED_FOR' => 'not_ip_address'
-    assert_equal nil, request.remote_ip
+    request = stub_request "HTTP_X_FORWARDED_FOR" => "not_ip_address"
+    assert_nil request.remote_ip
   end
 
   test "remote ip spoof detection" do
-    request = stub_request 'HTTP_X_FORWARDED_FOR' => '1.1.1.1',
-                           'HTTP_CLIENT_IP'       => '2.2.2.2'
+    request = stub_request "HTTP_X_FORWARDED_FOR" => "1.1.1.1",
+                           "HTTP_CLIENT_IP"       => "2.2.2.2"
     e = assert_raise(ActionDispatch::RemoteIp::IpSpoofAttackError) {
       request.remote_ip
     }
     assert_match(/IP spoofing attack/, e.message)
-    assert_match(/HTTP_X_FORWARDED_FOR="1.1.1.1"/, e.message)
-    assert_match(/HTTP_CLIENT_IP="2.2.2.2"/, e.message)
+    assert_match(/HTTP_X_FORWARDED_FOR="1\.1\.1\.1"/, e.message)
+    assert_match(/HTTP_CLIENT_IP="2\.2\.2\.2"/, e.message)
   end
 
   test "remote ip with spoof detection disabled" do
-    request = stub_request 'HTTP_X_FORWARDED_FOR' => '1.1.1.1',
-                           'HTTP_CLIENT_IP'       => '2.2.2.2',
+    request = stub_request "HTTP_X_FORWARDED_FOR" => "1.1.1.1",
+                           "HTTP_CLIENT_IP"       => "2.2.2.2",
                            :ip_spoofing_check => false
-    assert_equal '1.1.1.1', request.remote_ip
+    assert_equal "1.1.1.1", request.remote_ip
   end
 
   test "remote ip spoof protection ignores private addresses" do
-    request = stub_request 'HTTP_X_FORWARDED_FOR' => '172.17.19.51',
-                           'HTTP_CLIENT_IP'       => '172.17.19.51',
-                           'REMOTE_ADDR'          => '1.1.1.1',
-                           'HTTP_X_BLUECOAT_VIA'  => 'de462e07a2db325e'
-    assert_equal '1.1.1.1', request.remote_ip
+    request = stub_request "HTTP_X_FORWARDED_FOR" => "172.17.19.51",
+                           "HTTP_CLIENT_IP"       => "172.17.19.51",
+                           "REMOTE_ADDR"          => "1.1.1.1",
+                           "HTTP_X_BLUECOAT_VIA"  => "de462e07a2db325e"
+    assert_equal "1.1.1.1", request.remote_ip
   end
 
   test "remote ip v6" do
-    request = stub_request 'REMOTE_ADDR' => '2001:0db8:85a3:0000:0000:8a2e:0370:7334'
-    assert_equal '2001:0db8:85a3:0000:0000:8a2e:0370:7334', request.remote_ip
+    request = stub_request "REMOTE_ADDR" => "2001:0db8:85a3:0000:0000:8a2e:0370:7334"
+    assert_equal "2001:0db8:85a3:0000:0000:8a2e:0370:7334", request.remote_ip
 
-    request = stub_request 'REMOTE_ADDR' => 'fe80:0000:0000:0000:0202:b3ff:fe1e:8329,2001:0db8:85a3:0000:0000:8a2e:0370:7334'
-    assert_equal '2001:0db8:85a3:0000:0000:8a2e:0370:7334', request.remote_ip
+    request = stub_request "REMOTE_ADDR" => "fe80:0000:0000:0000:0202:b3ff:fe1e:8329,2001:0db8:85a3:0000:0000:8a2e:0370:7334"
+    assert_equal "2001:0db8:85a3:0000:0000:8a2e:0370:7334", request.remote_ip
 
-    request = stub_request 'REMOTE_ADDR' => '2001:0db8:85a3:0000:0000:8a2e:0370:7334',
-                           'HTTP_X_FORWARDED_FOR' => 'fe80:0000:0000:0000:0202:b3ff:fe1e:8329'
-    assert_equal 'fe80:0000:0000:0000:0202:b3ff:fe1e:8329', request.remote_ip
+    request = stub_request "REMOTE_ADDR" => "2001:0db8:85a3:0000:0000:8a2e:0370:7334",
+                           "HTTP_X_FORWARDED_FOR" => "fe80:0000:0000:0000:0202:b3ff:fe1e:8329"
+    assert_equal "fe80:0000:0000:0000:0202:b3ff:fe1e:8329", request.remote_ip
 
-    request = stub_request 'REMOTE_ADDR' => '::1',
-                           'HTTP_X_FORWARDED_FOR' => 'fe80:0000:0000:0000:0202:b3ff:fe1e:8329'
-    assert_equal 'fe80:0000:0000:0000:0202:b3ff:fe1e:8329', request.remote_ip
+    request = stub_request "REMOTE_ADDR" => "::1",
+                           "HTTP_X_FORWARDED_FOR" => "fe80:0000:0000:0000:0202:b3ff:fe1e:8329"
+    assert_equal "fe80:0000:0000:0000:0202:b3ff:fe1e:8329", request.remote_ip
 
-    request = stub_request 'HTTP_X_FORWARDED_FOR' => 'fe80:0000:0000:0000:0202:b3ff:fe1e:8329,unknown'
-    assert_equal 'fe80:0000:0000:0000:0202:b3ff:fe1e:8329', request.remote_ip
+    request = stub_request "HTTP_X_FORWARDED_FOR" => "fe80:0000:0000:0000:0202:b3ff:fe1e:8329,unknown"
+    assert_equal "fe80:0000:0000:0000:0202:b3ff:fe1e:8329", request.remote_ip
 
-    request = stub_request 'HTTP_X_FORWARDED_FOR' => 'fe80:0000:0000:0000:0202:b3ff:fe1e:8329,::1'
-    assert_equal 'fe80:0000:0000:0000:0202:b3ff:fe1e:8329', request.remote_ip
+    request = stub_request "HTTP_X_FORWARDED_FOR" => "fe80:0000:0000:0000:0202:b3ff:fe1e:8329,::1"
+    assert_equal "fe80:0000:0000:0000:0202:b3ff:fe1e:8329", request.remote_ip
 
-    request = stub_request 'HTTP_X_FORWARDED_FOR' => 'fe80:0000:0000:0000:0202:b3ff:fe1e:8329, ::1, ::1'
-    assert_equal 'fe80:0000:0000:0000:0202:b3ff:fe1e:8329', request.remote_ip
+    request = stub_request "HTTP_X_FORWARDED_FOR" => "fe80:0000:0000:0000:0202:b3ff:fe1e:8329, ::1, ::1"
+    assert_equal "fe80:0000:0000:0000:0202:b3ff:fe1e:8329", request.remote_ip
 
-    request = stub_request 'HTTP_X_FORWARDED_FOR' => 'unknown,::1'
-    assert_equal nil, request.remote_ip
+    request = stub_request "HTTP_X_FORWARDED_FOR" => "unknown,::1"
+    assert_nil request.remote_ip
 
-    request = stub_request 'HTTP_X_FORWARDED_FOR' => '2001:0db8:85a3:0000:0000:8a2e:0370:7334, fe80:0000:0000:0000:0202:b3ff:fe1e:8329, ::1, fc00::, fc01::, fdff'
-    assert_equal 'fe80:0000:0000:0000:0202:b3ff:fe1e:8329', request.remote_ip
+    request = stub_request "HTTP_X_FORWARDED_FOR" => "2001:0db8:85a3:0000:0000:8a2e:0370:7334, fe80:0000:0000:0000:0202:b3ff:fe1e:8329, ::1, fc00::, fc01::, fdff"
+    assert_equal "fe80:0000:0000:0000:0202:b3ff:fe1e:8329", request.remote_ip
 
-    request = stub_request 'HTTP_X_FORWARDED_FOR' => 'FE00::, FDFF::'
-    assert_equal 'FE00::', request.remote_ip
+    request = stub_request "HTTP_X_FORWARDED_FOR" => "FE00::, FDFF::"
+    assert_equal "FE00::", request.remote_ip
 
-    request = stub_request 'HTTP_X_FORWARDED_FOR' => 'not_ip_address'
-    assert_equal nil, request.remote_ip
+    request = stub_request "HTTP_X_FORWARDED_FOR" => "not_ip_address"
+    assert_nil request.remote_ip
   end
 
   test "remote ip v6 spoof detection" do
-    request = stub_request 'HTTP_X_FORWARDED_FOR' => 'fe80:0000:0000:0000:0202:b3ff:fe1e:8329',
-                           'HTTP_CLIENT_IP'       => '2001:0db8:85a3:0000:0000:8a2e:0370:7334'
+    request = stub_request "HTTP_X_FORWARDED_FOR" => "fe80:0000:0000:0000:0202:b3ff:fe1e:8329",
+                           "HTTP_CLIENT_IP"       => "2001:0db8:85a3:0000:0000:8a2e:0370:7334"
     e = assert_raise(ActionDispatch::RemoteIp::IpSpoofAttackError) {
       request.remote_ip
     }
@@ -178,139 +180,139 @@ class RequestIP < BaseRequestTest
   end
 
   test "remote ip v6 spoof detection disabled" do
-    request = stub_request 'HTTP_X_FORWARDED_FOR' => 'fe80:0000:0000:0000:0202:b3ff:fe1e:8329',
-                           'HTTP_CLIENT_IP'       => '2001:0db8:85a3:0000:0000:8a2e:0370:7334',
+    request = stub_request "HTTP_X_FORWARDED_FOR" => "fe80:0000:0000:0000:0202:b3ff:fe1e:8329",
+                           "HTTP_CLIENT_IP"       => "2001:0db8:85a3:0000:0000:8a2e:0370:7334",
                            :ip_spoofing_check     => false
-    assert_equal 'fe80:0000:0000:0000:0202:b3ff:fe1e:8329', request.remote_ip
+    assert_equal "fe80:0000:0000:0000:0202:b3ff:fe1e:8329", request.remote_ip
   end
 
   test "remote ip with user specified trusted proxies String" do
     @trusted_proxies = "67.205.106.73"
 
-    request = stub_request 'REMOTE_ADDR' => '3.4.5.6',
-                           'HTTP_X_FORWARDED_FOR' => '67.205.106.73'
-    assert_equal '3.4.5.6', request.remote_ip
+    request = stub_request "REMOTE_ADDR" => "3.4.5.6",
+                           "HTTP_X_FORWARDED_FOR" => "67.205.106.73"
+    assert_equal "3.4.5.6", request.remote_ip
 
-    request = stub_request 'REMOTE_ADDR' => '172.16.0.1,67.205.106.73',
-                           'HTTP_X_FORWARDED_FOR' => '67.205.106.73'
-    assert_equal '67.205.106.73', request.remote_ip
+    request = stub_request "REMOTE_ADDR" => "172.16.0.1,67.205.106.73",
+                           "HTTP_X_FORWARDED_FOR" => "67.205.106.73"
+    assert_equal "67.205.106.73", request.remote_ip
 
-    request = stub_request 'REMOTE_ADDR' => '67.205.106.73,3.4.5.6',
-                           'HTTP_X_FORWARDED_FOR' => '67.205.106.73'
-    assert_equal '3.4.5.6', request.remote_ip
+    request = stub_request "REMOTE_ADDR" => "67.205.106.73,3.4.5.6",
+                           "HTTP_X_FORWARDED_FOR" => "67.205.106.73"
+    assert_equal "3.4.5.6", request.remote_ip
 
-    request = stub_request 'HTTP_X_FORWARDED_FOR' => '67.205.106.73,unknown'
-    assert_equal nil, request.remote_ip
+    request = stub_request "HTTP_X_FORWARDED_FOR" => "67.205.106.73,unknown"
+    assert_nil request.remote_ip
 
-    request = stub_request 'HTTP_X_FORWARDED_FOR' => '9.9.9.9, 3.4.5.6, 10.0.0.1, 67.205.106.73'
-    assert_equal '3.4.5.6', request.remote_ip
+    request = stub_request "HTTP_X_FORWARDED_FOR" => "9.9.9.9, 3.4.5.6, 10.0.0.1, 67.205.106.73"
+    assert_equal "3.4.5.6", request.remote_ip
   end
 
   test "remote ip v6 with user specified trusted proxies String" do
-    @trusted_proxies = 'fe80:0000:0000:0000:0202:b3ff:fe1e:8329'
+    @trusted_proxies = "fe80:0000:0000:0000:0202:b3ff:fe1e:8329"
 
-    request = stub_request 'REMOTE_ADDR' => '2001:0db8:85a3:0000:0000:8a2e:0370:7334',
-                           'HTTP_X_FORWARDED_FOR' => 'fe80:0000:0000:0000:0202:b3ff:fe1e:8329'
-    assert_equal '2001:0db8:85a3:0000:0000:8a2e:0370:7334', request.remote_ip
+    request = stub_request "REMOTE_ADDR" => "2001:0db8:85a3:0000:0000:8a2e:0370:7334",
+                           "HTTP_X_FORWARDED_FOR" => "fe80:0000:0000:0000:0202:b3ff:fe1e:8329"
+    assert_equal "2001:0db8:85a3:0000:0000:8a2e:0370:7334", request.remote_ip
 
-    request = stub_request 'REMOTE_ADDR' => 'fe80:0000:0000:0000:0202:b3ff:fe1e:8329,2001:0db8:85a3:0000:0000:8a2e:0370:7334',
-                           'HTTP_X_FORWARDED_FOR' => 'fe80:0000:0000:0000:0202:b3ff:fe1e:8329'
-    assert_equal '2001:0db8:85a3:0000:0000:8a2e:0370:7334', request.remote_ip
+    request = stub_request "REMOTE_ADDR" => "fe80:0000:0000:0000:0202:b3ff:fe1e:8329,2001:0db8:85a3:0000:0000:8a2e:0370:7334",
+                           "HTTP_X_FORWARDED_FOR" => "fe80:0000:0000:0000:0202:b3ff:fe1e:8329"
+    assert_equal "2001:0db8:85a3:0000:0000:8a2e:0370:7334", request.remote_ip
 
-    request = stub_request 'REMOTE_ADDR' => 'fe80:0000:0000:0000:0202:b3ff:fe1e:8329,::1',
-                           'HTTP_X_FORWARDED_FOR' => 'fe80:0000:0000:0000:0202:b3ff:fe1e:8329'
-    assert_equal '::1', request.remote_ip
+    request = stub_request "REMOTE_ADDR" => "fe80:0000:0000:0000:0202:b3ff:fe1e:8329,::1",
+                           "HTTP_X_FORWARDED_FOR" => "fe80:0000:0000:0000:0202:b3ff:fe1e:8329"
+    assert_equal "::1", request.remote_ip
 
-    request = stub_request 'HTTP_X_FORWARDED_FOR' => 'unknown,fe80:0000:0000:0000:0202:b3ff:fe1e:8329'
-    assert_equal nil, request.remote_ip
+    request = stub_request "HTTP_X_FORWARDED_FOR" => "unknown,fe80:0000:0000:0000:0202:b3ff:fe1e:8329"
+    assert_nil request.remote_ip
 
-    request = stub_request 'HTTP_X_FORWARDED_FOR' => 'fe80:0000:0000:0000:0202:b3ff:fe1e:8329,2001:0db8:85a3:0000:0000:8a2e:0370:7334'
+    request = stub_request "HTTP_X_FORWARDED_FOR" => "fe80:0000:0000:0000:0202:b3ff:fe1e:8329,2001:0db8:85a3:0000:0000:8a2e:0370:7334"
     assert_equal "2001:0db8:85a3:0000:0000:8a2e:0370:7334", request.remote_ip
   end
 
   test "remote ip with user specified trusted proxies Regexp" do
     @trusted_proxies = /^67\.205\.106\.73$/i
 
-    request = stub_request 'REMOTE_ADDR' => '67.205.106.73',
-                           'HTTP_X_FORWARDED_FOR' => '3.4.5.6'
-    assert_equal '3.4.5.6', request.remote_ip
+    request = stub_request "REMOTE_ADDR" => "67.205.106.73",
+                           "HTTP_X_FORWARDED_FOR" => "3.4.5.6"
+    assert_equal "3.4.5.6", request.remote_ip
 
-    request = stub_request 'HTTP_X_FORWARDED_FOR' => '10.0.0.1, 9.9.9.9, 3.4.5.6, 67.205.106.73'
-    assert_equal '3.4.5.6', request.remote_ip
+    request = stub_request "HTTP_X_FORWARDED_FOR" => "10.0.0.1, 9.9.9.9, 3.4.5.6, 67.205.106.73"
+    assert_equal "3.4.5.6", request.remote_ip
   end
 
   test "remote ip v6 with user specified trusted proxies Regexp" do
     @trusted_proxies = /^fe80:0000:0000:0000:0202:b3ff:fe1e:8329$/i
 
-    request = stub_request 'REMOTE_ADDR' => '2001:0db8:85a3:0000:0000:8a2e:0370:7334',
-                           'HTTP_X_FORWARDED_FOR' => 'fe80:0000:0000:0000:0202:b3ff:fe1e:8329'
-    assert_equal '2001:0db8:85a3:0000:0000:8a2e:0370:7334', request.remote_ip
+    request = stub_request "REMOTE_ADDR" => "2001:0db8:85a3:0000:0000:8a2e:0370:7334",
+                           "HTTP_X_FORWARDED_FOR" => "fe80:0000:0000:0000:0202:b3ff:fe1e:8329"
+    assert_equal "2001:0db8:85a3:0000:0000:8a2e:0370:7334", request.remote_ip
 
-    request = stub_request 'HTTP_X_FORWARDED_FOR' => '2001:0db8:85a3:0000:0000:8a2e:0370:7334, fe80:0000:0000:0000:0202:b3ff:fe1e:8329'
-    assert_equal '2001:0db8:85a3:0000:0000:8a2e:0370:7334', request.remote_ip
+    request = stub_request "HTTP_X_FORWARDED_FOR" => "2001:0db8:85a3:0000:0000:8a2e:0370:7334, fe80:0000:0000:0000:0202:b3ff:fe1e:8329"
+    assert_equal "2001:0db8:85a3:0000:0000:8a2e:0370:7334", request.remote_ip
   end
 
   test "remote ip middleware not present still returns an IP" do
-    request = stub_request('REMOTE_ADDR' => '127.0.0.1')
-    assert_equal '127.0.0.1', request.remote_ip
+    request = stub_request("REMOTE_ADDR" => "127.0.0.1")
+    assert_equal "127.0.0.1", request.remote_ip
   end
 end
 
 class RequestDomain < BaseRequestTest
   test "domains" do
-    request = stub_request 'HTTP_HOST' => "192.168.1.200"
+    request = stub_request "HTTP_HOST" => "192.168.1.200"
     assert_nil request.domain
 
-    request = stub_request 'HTTP_HOST' => "foo.192.168.1.200"
+    request = stub_request "HTTP_HOST" => "foo.192.168.1.200"
     assert_nil request.domain
 
-    request = stub_request 'HTTP_HOST' => "192.168.1.200.com"
+    request = stub_request "HTTP_HOST" => "192.168.1.200.com"
     assert_equal "200.com", request.domain
 
-    request = stub_request 'HTTP_HOST' => 'www.rubyonrails.org'
+    request = stub_request "HTTP_HOST" => "www.rubyonrails.org"
     assert_equal "rubyonrails.org", request.domain
 
-    request = stub_request 'HTTP_HOST' => "www.rubyonrails.co.uk"
+    request = stub_request "HTTP_HOST" => "www.rubyonrails.co.uk"
     assert_equal "rubyonrails.co.uk", request.domain(2)
 
-    request = stub_request 'HTTP_HOST' => "www.rubyonrails.co.uk", :tld_length => 2
+    request = stub_request "HTTP_HOST" => "www.rubyonrails.co.uk", :tld_length => 2
     assert_equal "rubyonrails.co.uk", request.domain
   end
 
   test "subdomains" do
-    request = stub_request 'HTTP_HOST' => "foobar.foobar.com"
+    request = stub_request "HTTP_HOST" => "foobar.foobar.com"
     assert_equal %w( foobar ), request.subdomains
     assert_equal "foobar", request.subdomain
 
-    request = stub_request 'HTTP_HOST' => "192.168.1.200"
+    request = stub_request "HTTP_HOST" => "192.168.1.200"
     assert_equal [], request.subdomains
     assert_equal "", request.subdomain
 
-    request = stub_request 'HTTP_HOST' => "foo.192.168.1.200"
+    request = stub_request "HTTP_HOST" => "foo.192.168.1.200"
     assert_equal [], request.subdomains
     assert_equal "", request.subdomain
 
-    request = stub_request 'HTTP_HOST' => "192.168.1.200.com"
+    request = stub_request "HTTP_HOST" => "192.168.1.200.com"
     assert_equal %w( 192 168 1 ), request.subdomains
     assert_equal "192.168.1", request.subdomain
 
-    request = stub_request 'HTTP_HOST' => nil
+    request = stub_request "HTTP_HOST" => nil
     assert_equal [], request.subdomains
     assert_equal "", request.subdomain
 
-    request = stub_request 'HTTP_HOST' => "www.rubyonrails.org"
+    request = stub_request "HTTP_HOST" => "www.rubyonrails.org"
     assert_equal %w( www ), request.subdomains
     assert_equal "www", request.subdomain
 
-    request = stub_request 'HTTP_HOST' => "www.rubyonrails.co.uk"
+    request = stub_request "HTTP_HOST" => "www.rubyonrails.co.uk"
     assert_equal %w( www ), request.subdomains(2)
     assert_equal "www", request.subdomain(2)
 
-    request = stub_request 'HTTP_HOST' => "dev.www.rubyonrails.co.uk"
+    request = stub_request "HTTP_HOST" => "dev.www.rubyonrails.co.uk"
     assert_equal %w( dev www ), request.subdomains(2)
     assert_equal "dev.www", request.subdomain(2)
 
-    request = stub_request 'HTTP_HOST' => "dev.www.rubyonrails.co.uk", :tld_length => 2
+    request = stub_request "HTTP_HOST" => "dev.www.rubyonrails.co.uk", :tld_length => 2
     assert_equal %w( dev www ), request.subdomains
     assert_equal "dev.www", request.subdomain
   end
@@ -321,7 +323,7 @@ class RequestPort < BaseRequestTest
     request = stub_request
     assert_equal 80, request.standard_port
 
-    request = stub_request 'HTTPS' => 'on'
+    request = stub_request "HTTPS" => "on"
     assert_equal 443, request.standard_port
   end
 
@@ -330,97 +332,97 @@ class RequestPort < BaseRequestTest
     assert !request.ssl?
     assert request.standard_port?
 
-    request = stub_request 'HTTPS' => 'on'
+    request = stub_request "HTTPS" => "on"
     assert request.ssl?
     assert request.standard_port?
 
-    request = stub_request 'HTTP_HOST' => 'www.example.org:8080'
+    request = stub_request "HTTP_HOST" => "www.example.org:8080"
     assert !request.ssl?
     assert !request.standard_port?
 
-    request = stub_request 'HTTP_HOST' => 'www.example.org:8443', 'HTTPS' => 'on'
+    request = stub_request "HTTP_HOST" => "www.example.org:8443", "HTTPS" => "on"
     assert request.ssl?
     assert !request.standard_port?
   end
 
   test "optional port" do
-    request = stub_request 'HTTP_HOST' => 'www.example.org:80'
-    assert_equal nil, request.optional_port
+    request = stub_request "HTTP_HOST" => "www.example.org:80"
+    assert_nil request.optional_port
 
-    request = stub_request 'HTTP_HOST' => 'www.example.org:8080'
+    request = stub_request "HTTP_HOST" => "www.example.org:8080"
     assert_equal 8080, request.optional_port
   end
 
   test "port string" do
-    request = stub_request 'HTTP_HOST' => 'www.example.org:80'
-    assert_equal '', request.port_string
+    request = stub_request "HTTP_HOST" => "www.example.org:80"
+    assert_equal "", request.port_string
 
-    request = stub_request 'HTTP_HOST' => 'www.example.org:8080'
-    assert_equal ':8080', request.port_string
+    request = stub_request "HTTP_HOST" => "www.example.org:8080"
+    assert_equal ":8080", request.port_string
   end
 
   test "server port" do
-    request = stub_request 'SERVER_PORT' => '8080'
+    request = stub_request "SERVER_PORT" => "8080"
     assert_equal 8080, request.server_port
 
-    request = stub_request 'SERVER_PORT' => '80'
+    request = stub_request "SERVER_PORT" => "80"
     assert_equal 80, request.server_port
 
-    request = stub_request 'SERVER_PORT' => ''
+    request = stub_request "SERVER_PORT" => ""
     assert_equal 0, request.server_port
   end
 end
 
 class RequestPath < BaseRequestTest
   test "full path" do
-    request = stub_request 'SCRIPT_NAME' => '', 'PATH_INFO' => '/path/of/some/uri', 'QUERY_STRING' => 'mapped=1'
+    request = stub_request "SCRIPT_NAME" => "", "PATH_INFO" => "/path/of/some/uri", "QUERY_STRING" => "mapped=1"
     assert_equal "/path/of/some/uri?mapped=1", request.fullpath
     assert_equal "/path/of/some/uri",          request.path_info
 
-    request = stub_request 'SCRIPT_NAME' => '', 'PATH_INFO' => '/path/of/some/uri'
+    request = stub_request "SCRIPT_NAME" => "", "PATH_INFO" => "/path/of/some/uri"
     assert_equal "/path/of/some/uri", request.fullpath
     assert_equal "/path/of/some/uri", request.path_info
 
-    request = stub_request 'SCRIPT_NAME' => '', 'PATH_INFO' => '/'
+    request = stub_request "SCRIPT_NAME" => "", "PATH_INFO" => "/"
     assert_equal "/", request.fullpath
     assert_equal "/", request.path_info
 
-    request = stub_request 'SCRIPT_NAME' => '', 'PATH_INFO' => '/', 'QUERY_STRING' => 'm=b'
+    request = stub_request "SCRIPT_NAME" => "", "PATH_INFO" => "/", "QUERY_STRING" => "m=b"
     assert_equal "/?m=b", request.fullpath
     assert_equal "/",     request.path_info
 
-    request = stub_request 'SCRIPT_NAME' => '/hieraki', 'PATH_INFO' => '/'
+    request = stub_request "SCRIPT_NAME" => "/hieraki", "PATH_INFO" => "/"
     assert_equal "/hieraki/", request.fullpath
     assert_equal "/",         request.path_info
 
-    request = stub_request 'SCRIPT_NAME' => '/collaboration/hieraki', 'PATH_INFO' => '/books/edit/2'
+    request = stub_request "SCRIPT_NAME" => "/collaboration/hieraki", "PATH_INFO" => "/books/edit/2"
     assert_equal "/collaboration/hieraki/books/edit/2", request.fullpath
     assert_equal "/books/edit/2",                       request.path_info
 
-    request = stub_request 'SCRIPT_NAME' => '/path', 'PATH_INFO' => '/of/some/uri', 'QUERY_STRING' => 'mapped=1'
+    request = stub_request "SCRIPT_NAME" => "/path", "PATH_INFO" => "/of/some/uri", "QUERY_STRING" => "mapped=1"
     assert_equal "/path/of/some/uri?mapped=1", request.fullpath
     assert_equal "/of/some/uri",               request.path_info
   end
 
   test "original_fullpath returns ORIGINAL_FULLPATH" do
-    request = stub_request('ORIGINAL_FULLPATH' => "/foo?bar")
+    request = stub_request("ORIGINAL_FULLPATH" => "/foo?bar")
 
     path = request.original_fullpath
     assert_equal "/foo?bar", path
   end
 
   test "original_url returns url built using ORIGINAL_FULLPATH" do
-    request = stub_request('ORIGINAL_FULLPATH' => "/foo?bar",
-                           'HTTP_HOST'         => "example.org",
-                           'rack.url_scheme'   => "http")
+    request = stub_request("ORIGINAL_FULLPATH" => "/foo?bar",
+                           "HTTP_HOST"         => "example.org",
+                           "rack.url_scheme"   => "http")
 
     url = request.original_url
     assert_equal "http://example.org/foo?bar", url
   end
 
   test "original_fullpath returns fullpath if ORIGINAL_FULLPATH is not present" do
-    request = stub_request('PATH_INFO'    => "/foo",
-                           'QUERY_STRING' => "bar")
+    request = stub_request("PATH_INFO"    => "/foo",
+                           "QUERY_STRING" => "bar")
 
     path = request.original_fullpath
     assert_equal "/foo?bar", path
@@ -429,77 +431,77 @@ end
 
 class RequestHost < BaseRequestTest
   test "host without specifying port" do
-    request = stub_request 'HTTP_HOST' => 'rubyonrails.org'
+    request = stub_request "HTTP_HOST" => "rubyonrails.org"
     assert_equal "rubyonrails.org", request.host_with_port
   end
 
   test "host with default port" do
-    request = stub_request 'HTTP_HOST' => 'rubyonrails.org:80'
+    request = stub_request "HTTP_HOST" => "rubyonrails.org:80"
     assert_equal "rubyonrails.org", request.host_with_port
   end
 
   test "host with non default port" do
-    request = stub_request 'HTTP_HOST' => 'rubyonrails.org:81'
+    request = stub_request "HTTP_HOST" => "rubyonrails.org:81"
     assert_equal "rubyonrails.org:81", request.host_with_port
   end
 
   test "raw without specifying port" do
-    request = stub_request 'HTTP_HOST' => 'rubyonrails.org'
+    request = stub_request "HTTP_HOST" => "rubyonrails.org"
     assert_equal "rubyonrails.org", request.raw_host_with_port
   end
 
   test "raw host with default port" do
-    request = stub_request 'HTTP_HOST' => 'rubyonrails.org:80'
+    request = stub_request "HTTP_HOST" => "rubyonrails.org:80"
     assert_equal "rubyonrails.org:80", request.raw_host_with_port
   end
 
   test "raw host with non default port" do
-    request = stub_request 'HTTP_HOST' => 'rubyonrails.org:81'
+    request = stub_request "HTTP_HOST" => "rubyonrails.org:81"
     assert_equal "rubyonrails.org:81", request.raw_host_with_port
   end
 
   test "proxy request" do
-    request = stub_request 'HTTP_HOST' => 'glu.ttono.us:80'
+    request = stub_request "HTTP_HOST" => "glu.ttono.us:80"
     assert_equal "glu.ttono.us", request.host_with_port
   end
 
   test "http host" do
-    request = stub_request 'HTTP_HOST' => "rubyonrails.org:8080"
+    request = stub_request "HTTP_HOST" => "rubyonrails.org:8080"
     assert_equal "rubyonrails.org", request.host
     assert_equal "rubyonrails.org:8080", request.host_with_port
 
-    request = stub_request 'HTTP_X_FORWARDED_HOST' => "www.firsthost.org, www.secondhost.org"
+    request = stub_request "HTTP_X_FORWARDED_HOST" => "www.firsthost.org, www.secondhost.org"
     assert_equal "www.secondhost.org", request.host
 
-    request = stub_request 'HTTP_X_FORWARDED_HOST' => "", 'HTTP_HOST' => "rubyonrails.org"
+    request = stub_request "HTTP_X_FORWARDED_HOST" => "", "HTTP_HOST" => "rubyonrails.org"
     assert_equal "rubyonrails.org", request.host
   end
 
   test "http host with default port overrides server port" do
-    request = stub_request 'HTTP_HOST' => "rubyonrails.org"
+    request = stub_request "HTTP_HOST" => "rubyonrails.org"
     assert_equal "rubyonrails.org", request.host_with_port
   end
 
   test "host with port if http standard port is specified" do
-    request = stub_request 'HTTP_X_FORWARDED_HOST' => "glu.ttono.us:80"
+    request = stub_request "HTTP_X_FORWARDED_HOST" => "glu.ttono.us:80"
     assert_equal "glu.ttono.us", request.host_with_port
   end
 
   test "host with port if https standard port is specified" do
     request = stub_request(
-      'HTTP_X_FORWARDED_PROTO' => "https",
-      'HTTP_X_FORWARDED_HOST' => "glu.ttono.us:443"
+      "HTTP_X_FORWARDED_PROTO" => "https",
+      "HTTP_X_FORWARDED_HOST" => "glu.ttono.us:443"
     )
     assert_equal "glu.ttono.us", request.host_with_port
   end
 
   test "host if ipv6 reference" do
-    request = stub_request 'HTTP_HOST' => "[2001:1234:5678:9abc:def0::dead:beef]"
+    request = stub_request "HTTP_HOST" => "[2001:1234:5678:9abc:def0::dead:beef]"
     assert_equal "[2001:1234:5678:9abc:def0::dead:beef]", request.host
   end
 
   test "host if ipv6 reference with port" do
-    request = stub_request 'HTTP_HOST' => "[2001:1234:5678:9abc:def0::dead:beef]:8008"
+    request = stub_request "HTTP_HOST" => "[2001:1234:5678:9abc:def0::dead:beef]:8008"
     assert_equal "[2001:1234:5678:9abc:def0::dead:beef]", request.host
   end
 end
@@ -537,7 +539,7 @@ class RequestCGI < BaseRequestTest
 
     assert_equal "Basic", request.auth_type
     assert_equal 0, request.content_length
-    assert_equal nil, request.content_mime_type
+    assert_nil request.content_mime_type
     assert_equal "CGI/1.1", request.gateway_interface
     assert_equal "*/*", request.accept
     assert_equal "UTF-8", request.accept_charset
@@ -581,7 +583,7 @@ class RequestCookie < BaseRequestTest
 
     # some Nokia phone browsers omit the space after the semicolon separator.
     # some developers have grown accustomed to using comma in cookie values.
-    request = stub_request("HTTP_COOKIE"=>"_session_id=c84ace847,96670c052c6ceb2451fb0f2;is_admin=yes")
+    request = stub_request("HTTP_COOKIE" => "_session_id=c84ace847,96670c052c6ceb2451fb0f2;is_admin=yes")
     assert_equal "c84ace847", request.cookies["_session_id"], request.cookies.inspect
     assert_equal "yes", request.cookies["is_admin"], request.cookies.inspect
   end
@@ -590,28 +592,28 @@ end
 class RequestParamsParsing < BaseRequestTest
   test "doesnt break when content type has charset" do
     request = stub_request(
-      'REQUEST_METHOD' => 'POST',
-      'CONTENT_LENGTH' => "flamenco=love".length,
-      'CONTENT_TYPE' => 'application/x-www-form-urlencoded; charset=utf-8',
-      'rack.input' => StringIO.new("flamenco=love")
+      "REQUEST_METHOD" => "POST",
+      "CONTENT_LENGTH" => "flamenco=love".length,
+      "CONTENT_TYPE" => "application/x-www-form-urlencoded; charset=utf-8",
+      "rack.input" => StringIO.new("flamenco=love")
     )
 
-    assert_equal({"flamenco"=> "love"}, request.request_parameters)
+    assert_equal({ "flamenco" => "love" }, request.request_parameters)
   end
 
   test "doesnt interpret request uri as query string when missing" do
-    request = stub_request('REQUEST_URI' => 'foo')
+    request = stub_request("REQUEST_URI" => "foo")
     assert_equal({}, request.query_parameters)
   end
 end
 
 class RequestRewind < BaseRequestTest
   test "body should be rewound" do
-    data = 'rewind'
+    data = "rewind"
     env = {
-      'rack.input' => StringIO.new(data),
-      'CONTENT_LENGTH' => data.length,
-      'CONTENT_TYPE' => 'application/x-www-form-urlencoded; charset=utf-8'
+      "rack.input" => StringIO.new(data),
+      "CONTENT_LENGTH" => data.length,
+      "CONTENT_TYPE" => "application/x-www-form-urlencoded; charset=utf-8"
     }
 
     # Read the request body by parsing params.
@@ -624,18 +626,18 @@ class RequestRewind < BaseRequestTest
 
   test "raw_post rewinds rack.input if RAW_POST_DATA is nil" do
     request = stub_request(
-      'rack.input' => StringIO.new("raw"),
-      'CONTENT_LENGTH' => 3
+      "rack.input" => StringIO.new("raw"),
+      "CONTENT_LENGTH" => 3
     )
     assert_equal "raw", request.raw_post
-    assert_equal "raw", request.env['rack.input'].read
+    assert_equal "raw", request.env["rack.input"].read
   end
 end
 
 class RequestProtocol < BaseRequestTest
   test "server software" do
-    assert_equal 'lighttpd', stub_request('SERVER_SOFTWARE' => 'lighttpd/1.4.5').server_software
-    assert_equal 'apache', stub_request('SERVER_SOFTWARE' => 'Apache3.422').server_software
+    assert_equal "lighttpd", stub_request("SERVER_SOFTWARE" => "lighttpd/1.4.5").server_software
+    assert_equal "apache", stub_request("SERVER_SOFTWARE" => "Apache3.422").server_software
   end
 
   test "xml http request" do
@@ -644,35 +646,35 @@ class RequestProtocol < BaseRequestTest
     assert !request.xml_http_request?
     assert !request.xhr?
 
-    request = stub_request 'HTTP_X_REQUESTED_WITH' => 'DefinitelyNotAjax1.0'
+    request = stub_request "HTTP_X_REQUESTED_WITH" => "DefinitelyNotAjax1.0"
     assert !request.xml_http_request?
     assert !request.xhr?
 
-    request = stub_request 'HTTP_X_REQUESTED_WITH' => 'XMLHttpRequest'
+    request = stub_request "HTTP_X_REQUESTED_WITH" => "XMLHttpRequest"
     assert request.xml_http_request?
     assert request.xhr?
   end
 
   test "reports ssl" do
     assert !stub_request.ssl?
-    assert stub_request('HTTPS' => 'on').ssl?
+    assert stub_request("HTTPS" => "on").ssl?
   end
 
   test "reports ssl when proxied via lighttpd" do
-    assert stub_request('HTTP_X_FORWARDED_PROTO' => 'https').ssl?
+    assert stub_request("HTTP_X_FORWARDED_PROTO" => "https").ssl?
   end
 
   test "scheme returns https when proxied" do
-    request = stub_request 'rack.url_scheme' => 'http'
+    request = stub_request "rack.url_scheme" => "http"
     assert !request.ssl?
-    assert_equal 'http', request.scheme
+    assert_equal "http", request.scheme
 
     request = stub_request(
-      'rack.url_scheme' => 'http',
-      'HTTP_X_FORWARDED_PROTO' => 'https'
+      "rack.url_scheme" => "http",
+      "HTTP_X_FORWARDED_PROTO" => "https"
     )
     assert request.ssl?
-    assert_equal 'https', request.scheme
+    assert_equal "https", request.scheme
   end
 end
 
@@ -681,7 +683,7 @@ class RequestMethod < BaseRequestTest
     overridden by middleware".squish do
 
     ActionDispatch::Request::HTTP_METHODS.each do |method|
-      request = stub_request('REQUEST_METHOD' => method)
+      request = stub_request("REQUEST_METHOD" => method)
 
       assert_equal method, request.method
       assert_equal method.underscore.to_sym, request.method_symbol
@@ -689,36 +691,36 @@ class RequestMethod < BaseRequestTest
   end
 
   test "allow request method hacking" do
-    request = stub_request('REQUEST_METHOD' => 'POST')
+    request = stub_request("REQUEST_METHOD" => "POST")
 
-    assert_equal 'POST', request.request_method
-    assert_equal 'POST', request.env["REQUEST_METHOD"]
+    assert_equal "POST", request.request_method
+    assert_equal "POST", request.env["REQUEST_METHOD"]
 
-    request.request_method = 'GET'
+    request.request_method = "GET"
 
-    assert_equal 'GET', request.request_method
-    assert_equal 'GET', request.env["REQUEST_METHOD"]
+    assert_equal "GET", request.request_method
+    assert_equal "GET", request.env["REQUEST_METHOD"]
     assert request.get?
   end
 
   test "invalid http method raises exception" do
     assert_raise(ActionController::UnknownHttpMethod) do
-      stub_request('REQUEST_METHOD' => 'RANDOM_METHOD').request_method
+      stub_request("REQUEST_METHOD" => "RANDOM_METHOD").request_method
     end
   end
 
   test "method returns original value of environment request method on POST" do
-    request = stub_request('rack.methodoverride.original_method' => 'POST')
-    assert_equal 'POST', request.method
+    request = stub_request("rack.methodoverride.original_method" => "POST")
+    assert_equal "POST", request.method
   end
 
   test "method raises exception on invalid HTTP method" do
     assert_raise(ActionController::UnknownHttpMethod) do
-      stub_request('rack.methodoverride.original_method' => '_RANDOM_METHOD').method
+      stub_request("rack.methodoverride.original_method" => "_RANDOM_METHOD").method
     end
 
     assert_raise(ActionController::UnknownHttpMethod) do
-      stub_request('REQUEST_METHOD' => '_RANDOM_METHOD').method
+      stub_request("REQUEST_METHOD" => "_RANDOM_METHOD").method
     end
   end
 
@@ -730,7 +732,7 @@ class RequestMethod < BaseRequestTest
       I18n.available_locales = [:nl]
       I18n.config.enforce_available_locales = true
       assert_raise(ActionController::UnknownHttpMethod) do
-        stub_request('REQUEST_METHOD' => '_RANDOM_METHOD').method
+        stub_request("REQUEST_METHOD" => "_RANDOM_METHOD").method
       end
     ensure
       I18n.available_locales = old_locales
@@ -740,7 +742,7 @@ class RequestMethod < BaseRequestTest
 
   test "post masquerading as patch" do
     request = stub_request(
-      'REQUEST_METHOD' => 'PATCH',
+      "REQUEST_METHOD" => "PATCH",
       "rack.methodoverride.original_method" => "POST"
     )
 
@@ -751,7 +753,7 @@ class RequestMethod < BaseRequestTest
 
   test "post masquerading as put" do
     request = stub_request(
-      'REQUEST_METHOD' => 'PUT',
+      "REQUEST_METHOD" => "PUT",
       "rack.methodoverride.original_method" => "POST"
     )
     assert_equal "POST", request.method
@@ -760,8 +762,8 @@ class RequestMethod < BaseRequestTest
   end
 
   test "post uneffected by local inflections" do
-    existing_acrnoyms = ActiveSupport::Inflector.inflections.acronyms.dup
-    existing_acrnoym_regex = ActiveSupport::Inflector.inflections.acronym_regex.dup
+    existing_acronyms = ActiveSupport::Inflector.inflections.acronyms.dup
+    assert_deprecated { ActiveSupport::Inflector.inflections.acronym_regex.dup }
     begin
       ActiveSupport::Inflector.inflections do |inflect|
         inflect.acronym "POS"
@@ -774,8 +776,8 @@ class RequestMethod < BaseRequestTest
     ensure
       # Reset original acronym set
       ActiveSupport::Inflector.inflections do |inflect|
-        inflect.send(:instance_variable_set,"@acronyms",existing_acrnoyms)
-        inflect.send(:instance_variable_set,"@acronym_regex",existing_acrnoym_regex)
+        inflect.send(:instance_variable_set, "@acronyms", existing_acronyms)
+        inflect.send(:define_acronym_regex_patterns)
       end
     end
   end
@@ -784,29 +786,29 @@ end
 class RequestFormat < BaseRequestTest
   test "xml format" do
     request = stub_request
-    assert_called(request, :parameters, times: 2, returns: {format: :xml}) do
+    assert_called(request, :parameters, times: 2, returns: { format: :xml }) do
       assert_equal Mime[:xml], request.format
     end
   end
 
   test "xhtml format" do
     request = stub_request
-    assert_called(request, :parameters, times: 2, returns: {format: :xhtml}) do
+    assert_called(request, :parameters, times: 2, returns: { format: :xhtml }) do
       assert_equal Mime[:html], request.format
     end
   end
 
   test "txt format" do
     request = stub_request
-    assert_called(request, :parameters, times: 2, returns: {format: :txt}) do
+    assert_called(request, :parameters, times: 2, returns: { format: :txt }) do
       assert_equal Mime[:text], request.format
     end
   end
 
   test "XMLHttpRequest" do
     request = stub_request(
-      'HTTP_X_REQUESTED_WITH' => 'XMLHttpRequest',
-      'HTTP_ACCEPT' => [Mime[:js], Mime[:html], Mime[:xml], "text/xml", "*/*"].join(",")
+      "HTTP_X_REQUESTED_WITH" => "XMLHttpRequest",
+      "HTTP_ACCEPT" => [Mime[:js], Mime[:html], Mime[:xml], "text/xml", "*/*"].join(",")
     )
 
     assert_called(request, :parameters, times: 1, returns: {}) do
@@ -817,56 +819,56 @@ class RequestFormat < BaseRequestTest
 
   test "can override format with parameter negative" do
     request = stub_request
-    assert_called(request, :parameters, times: 2, returns: {format: :txt}) do
+    assert_called(request, :parameters, times: 2, returns: { format: :txt }) do
       assert !request.format.xml?
     end
   end
 
   test "can override format with parameter positive" do
     request = stub_request
-    assert_called(request, :parameters, times: 2, returns: {format: :xml}) do
+    assert_called(request, :parameters, times: 2, returns: { format: :xml }) do
       assert request.format.xml?
     end
   end
 
   test "formats text/html with accept header" do
-    request = stub_request 'HTTP_ACCEPT' => 'text/html'
+    request = stub_request "HTTP_ACCEPT" => "text/html"
     assert_equal [Mime[:html]], request.formats
   end
 
   test "formats blank with accept header" do
-    request = stub_request 'HTTP_ACCEPT' => ''
+    request = stub_request "HTTP_ACCEPT" => ""
     assert_equal [Mime[:html]], request.formats
   end
 
   test "formats XMLHttpRequest with accept header" do
-    request = stub_request 'HTTP_X_REQUESTED_WITH' => "XMLHttpRequest"
+    request = stub_request "HTTP_X_REQUESTED_WITH" => "XMLHttpRequest"
     assert_equal [Mime[:js]], request.formats
   end
 
   test "formats application/xml with accept header" do
-    request = stub_request('CONTENT_TYPE' => 'application/xml; charset=UTF-8',
-                           'HTTP_X_REQUESTED_WITH' => "XMLHttpRequest")
+    request = stub_request("CONTENT_TYPE" => "application/xml; charset=UTF-8",
+                           "HTTP_X_REQUESTED_WITH" => "XMLHttpRequest")
     assert_equal [Mime[:xml]], request.formats
   end
 
   test "formats format:text with accept header" do
     request = stub_request
-    assert_called(request, :parameters, times: 2, returns: {format: :txt}) do
+    assert_called(request, :parameters, times: 2, returns: { format: :txt }) do
       assert_equal [Mime[:text]], request.formats
     end
   end
 
   test "formats format:unknown with accept header" do
     request = stub_request
-    assert_called(request, :parameters, times: 2, returns: {format: :unknown}) do
+    assert_called(request, :parameters, times: 2, returns: { format: :unknown }) do
       assert_instance_of Mime::NullType, request.format
     end
   end
 
   test "format is not nil with unknown format" do
     request = stub_request
-    assert_called(request, :parameters, times: 2, returns: {format: :hello}) do
+    assert_called(request, :parameters, times: 2, returns: { format: :hello }) do
       assert request.format.nil?
       assert_not request.format.html?
       assert_not request.format.xml?
@@ -881,7 +883,7 @@ class RequestFormat < BaseRequestTest
   end
 
   test "formats with xhr request" do
-    request = stub_request 'HTTP_X_REQUESTED_WITH' => "XMLHttpRequest"
+    request = stub_request "HTTP_X_REQUESTED_WITH" => "XMLHttpRequest"
     assert_called(request, :parameters, times: 1, returns: {}) do
       assert_equal [Mime[:js]], request.formats
     end
@@ -892,36 +894,36 @@ class RequestFormat < BaseRequestTest
     ActionDispatch::Request.ignore_accept_header = true
 
     begin
-      request = stub_request 'HTTP_ACCEPT' => 'application/xml'
+      request = stub_request "HTTP_ACCEPT" => "application/xml"
       assert_called(request, :parameters, times: 1, returns: {}) do
         assert_equal [ Mime[:html] ], request.formats
       end
 
-      request = stub_request 'HTTP_ACCEPT' => 'koz-asked/something-crazy'
+      request = stub_request "HTTP_ACCEPT" => "koz-asked/something-crazy"
       assert_called(request, :parameters, times: 1, returns: {}) do
         assert_equal [ Mime[:html] ], request.formats
       end
 
-      request = stub_request 'HTTP_ACCEPT' => '*/*;q=0.1'
+      request = stub_request "HTTP_ACCEPT" => "*/*;q=0.1"
       assert_called(request, :parameters, times: 1, returns: {}) do
         assert_equal [ Mime[:html] ], request.formats
       end
 
-      request = stub_request 'HTTP_ACCEPT' => 'application/jxw'
+      request = stub_request "HTTP_ACCEPT" => "application/jxw"
       assert_called(request, :parameters, times: 1, returns: {}) do
         assert_equal [ Mime[:html] ], request.formats
       end
 
-      request = stub_request 'HTTP_ACCEPT' => 'application/xml',
-                             'HTTP_X_REQUESTED_WITH' => "XMLHttpRequest"
+      request = stub_request "HTTP_ACCEPT" => "application/xml",
+                             "HTTP_X_REQUESTED_WITH" => "XMLHttpRequest"
 
       assert_called(request, :parameters, times: 1, returns: {}) do
         assert_equal [ Mime[:js] ], request.formats
       end
 
-      request = stub_request 'HTTP_ACCEPT' => 'application/xml',
-                             'HTTP_X_REQUESTED_WITH' => "XMLHttpRequest"
-      assert_called(request, :parameters, times: 2, returns: {format: :json}) do
+      request = stub_request "HTTP_ACCEPT" => "application/xml",
+                             "HTTP_X_REQUESTED_WITH" => "XMLHttpRequest"
+      assert_called(request, :parameters, times: 2, returns: { format: :json }) do
         assert_equal [ Mime[:json] ], request.formats
       end
     ensure
@@ -930,20 +932,20 @@ class RequestFormat < BaseRequestTest
   end
 
   test "format taken from the path extension" do
-    request = stub_request 'PATH_INFO' => '/foo.xml'
+    request = stub_request "PATH_INFO" => "/foo.xml"
     assert_called(request, :parameters, times: 1, returns: {}) do
       assert_equal [Mime[:xml]], request.formats
     end
 
-    request = stub_request 'PATH_INFO' => '/foo.123'
+    request = stub_request "PATH_INFO" => "/foo.123"
     assert_called(request, :parameters, times: 1, returns: {}) do
       assert_equal [Mime[:html]], request.formats
     end
   end
 
   test "formats from accept headers have higher precedence than path extension" do
-    request = stub_request 'HTTP_ACCEPT' => 'application/json',
-                           'PATH_INFO' => '/foo.xml'
+    request = stub_request "HTTP_ACCEPT" => "application/json",
+                           "PATH_INFO" => "/foo.xml"
 
     assert_called(request, :parameters, times: 1, returns: {}) do
       assert_equal [Mime[:json]], request.formats
@@ -953,40 +955,40 @@ end
 
 class RequestMimeType < BaseRequestTest
   test "content type" do
-    assert_equal Mime[:html], stub_request('CONTENT_TYPE' => 'text/html').content_mime_type
+    assert_equal Mime[:html], stub_request("CONTENT_TYPE" => "text/html").content_mime_type
   end
 
   test "no content type" do
-    assert_equal nil, stub_request.content_mime_type
+    assert_nil stub_request.content_mime_type
   end
 
   test "content type is XML" do
-    assert_equal Mime[:xml], stub_request('CONTENT_TYPE' => 'application/xml').content_mime_type
+    assert_equal Mime[:xml], stub_request("CONTENT_TYPE" => "application/xml").content_mime_type
   end
 
   test "content type with charset" do
-    assert_equal Mime[:xml], stub_request('CONTENT_TYPE' => 'application/xml; charset=UTF-8').content_mime_type
+    assert_equal Mime[:xml], stub_request("CONTENT_TYPE" => "application/xml; charset=UTF-8").content_mime_type
   end
 
   test "user agent" do
-    assert_equal 'TestAgent', stub_request('HTTP_USER_AGENT' => 'TestAgent').user_agent
+    assert_equal "TestAgent", stub_request("HTTP_USER_AGENT" => "TestAgent").user_agent
   end
 
   test "negotiate_mime" do
     request = stub_request(
-      'HTTP_ACCEPT' => 'text/html',
-      'HTTP_X_REQUESTED_WITH' => "XMLHttpRequest"
+      "HTTP_ACCEPT" => "text/html",
+      "HTTP_X_REQUESTED_WITH" => "XMLHttpRequest"
     )
 
-    assert_equal nil, request.negotiate_mime([Mime[:xml], Mime[:json]])
+    assert_nil request.negotiate_mime([Mime[:xml], Mime[:json]])
     assert_equal Mime[:html], request.negotiate_mime([Mime[:xml], Mime[:html]])
     assert_equal Mime[:html], request.negotiate_mime([Mime[:xml], Mime::ALL])
   end
 
   test "negotiate_mime with content_type" do
     request = stub_request(
-      'CONTENT_TYPE' => 'application/xml; charset=UTF-8',
-      'HTTP_X_REQUESTED_WITH' => "XMLHttpRequest"
+      "CONTENT_TYPE" => "application/xml; charset=UTF-8",
+      "HTTP_X_REQUESTED_WITH" => "XMLHttpRequest"
     )
 
     assert_equal Mime[:xml], request.negotiate_mime([Mime[:xml], Mime[:csv]])
@@ -997,11 +999,11 @@ class RequestParameters < BaseRequestTest
   test "parameters" do
     request = stub_request
 
-    assert_called(request, :request_parameters, times: 2, returns: {"foo" => 1}) do
-      assert_called(request, :query_parameters, times: 2, returns: {"bar" => 2}) do
-        assert_equal({"foo" => 1, "bar" => 2}, request.parameters)
-        assert_equal({"foo" => 1}, request.request_parameters)
-        assert_equal({"bar" => 2}, request.query_parameters)
+    assert_called(request, :request_parameters, times: 2, returns: { "foo" => 1 }) do
+      assert_called(request, :query_parameters, times: 2, returns: { "bar" => 2 }) do
+        assert_equal({ "foo" => 1, "bar" => 2 }, request.parameters)
+        assert_equal({ "foo" => 1 }, request.request_parameters)
+        assert_equal({ "bar" => 2 }, request.query_parameters)
       end
     end
   end
@@ -1018,17 +1020,14 @@ class RequestParameters < BaseRequestTest
   end
 
   test "path parameters with invalid UTF8 encoding" do
-    request = stub_request(
-      "action_dispatch.request.path_parameters" => { foo: "\xBE" }
-    )
+    request = stub_request
 
     err = assert_raises(ActionController::BadRequest) do
-      request.check_path_parameters!
+      request.path_parameters = { foo: "\xBE" }
     end
 
-    assert_match "Invalid parameter encoding", err.message
-    assert_match "foo", err.message
-    assert_match "\\xBE", err.message
+    assert_predicate err.message, :valid_encoding?
+    assert_equal "Invalid path parameters: Invalid encoding for parameter: �", err.message
   end
 
   test "parameters not accessible after rack parse error of invalid UTF8 character" do
@@ -1048,10 +1047,10 @@ class RequestParameters < BaseRequestTest
 
   test "parameters not accessible after rack parse error 1" do
     request = stub_request(
-      'REQUEST_METHOD' => 'POST',
-      'CONTENT_LENGTH' => "a%=".length,
-      'CONTENT_TYPE' => 'application/x-www-form-urlencoded; charset=utf-8',
-      'rack.input' => StringIO.new("a%=")
+      "REQUEST_METHOD" => "POST",
+      "CONTENT_LENGTH" => "a%=".length,
+      "CONTENT_TYPE" => "application/x-www-form-urlencoded; charset=utf-8",
+      "rack.input" => StringIO.new("a%=")
     )
 
     assert_raises(ActionController::BadRequest) do
@@ -1073,44 +1072,56 @@ class RequestParameters < BaseRequestTest
   end
 end
 
-
 class RequestParameterFilter < BaseRequestTest
   test "process parameter filter" do
     test_hashes = [
-    [{'foo'=>'bar'},{'foo'=>'bar'},%w'food'],
-    [{'foo'=>'bar'},{'foo'=>'[FILTERED]'},%w'foo'],
-    [{'foo'=>'bar', 'bar'=>'foo'},{'foo'=>'[FILTERED]', 'bar'=>'foo'},%w'foo baz'],
-    [{'foo'=>'bar', 'baz'=>'foo'},{'foo'=>'[FILTERED]', 'baz'=>'[FILTERED]'},%w'foo baz'],
-    [{'bar'=>{'foo'=>'bar','bar'=>'foo'}},{'bar'=>{'foo'=>'[FILTERED]','bar'=>'foo'}},%w'fo'],
-    [{'foo'=>{'foo'=>'bar','bar'=>'foo'}},{'foo'=>'[FILTERED]'},%w'f banana'],
-    [{'deep'=>{'cc'=>{'code'=>'bar','bar'=>'foo'},'ss'=>{'code'=>'bar'}}},{'deep'=>{'cc'=>{'code'=>'[FILTERED]','bar'=>'foo'},'ss'=>{'code'=>'bar'}}},%w'deep.cc.code'],
-    [{'baz'=>[{'foo'=>'baz'}, "1"]}, {'baz'=>[{'foo'=>'[FILTERED]'}, "1"]}, [/foo/]]]
+    [{ "foo" => "bar" }, { "foo" => "bar" }, %w'food'],
+    [{ "foo" => "bar" }, { "foo" => "[FILTERED]" }, %w'foo'],
+    [{ "foo" => "bar", "bar" => "foo" }, { "foo" => "[FILTERED]", "bar" => "foo" }, %w'foo baz'],
+    [{ "foo" => "bar", "baz" => "foo" }, { "foo" => "[FILTERED]", "baz" => "[FILTERED]" }, %w'foo baz'],
+    [{ "bar" => { "foo" => "bar", "bar" => "foo" } }, { "bar" => { "foo" => "[FILTERED]", "bar" => "foo" } }, %w'fo'],
+    [{ "foo" => { "foo" => "bar", "bar" => "foo" } }, { "foo" => "[FILTERED]" }, %w'f banana'],
+    [{ "deep" => { "cc" => { "code" => "bar", "bar" => "foo" }, "ss" => { "code" => "bar" } } }, { "deep" => { "cc" => { "code" => "[FILTERED]", "bar" => "foo" }, "ss" => { "code" => "bar" } } }, %w'deep.cc.code'],
+    [{ "baz" => [{ "foo" => "baz" }, "1"] }, { "baz" => [{ "foo" => "[FILTERED]" }, "1"] }, [/foo/]]]
 
     test_hashes.each do |before_filter, after_filter, filter_words|
       parameter_filter = ActionDispatch::Http::ParameterFilter.new(filter_words)
       assert_equal after_filter, parameter_filter.filter(before_filter)
 
-      filter_words << 'blah'
+      filter_words << "blah"
       filter_words << lambda { |key, value|
         value.reverse! if key =~ /bargain/
       }
 
       parameter_filter = ActionDispatch::Http::ParameterFilter.new(filter_words)
-      before_filter['barg'] = {:bargain=>'gain', 'blah'=>'bar', 'bar'=>{'bargain'=>{'blah'=>'foo'}}}
-      after_filter['barg']  = {:bargain=>'niag', 'blah'=>'[FILTERED]', 'bar'=>{'bargain'=>{'blah'=>'[FILTERED]'}}}
+      before_filter["barg"] = { :bargain => "gain", "blah" => "bar", "bar" => { "bargain" => { "blah" => "foo" } } }
+      after_filter["barg"]  = { :bargain => "niag", "blah" => "[FILTERED]", "bar" => { "bargain" => { "blah" => "[FILTERED]" } } }
 
       assert_equal after_filter, parameter_filter.filter(before_filter)
     end
   end
 
+  test "parameter filter should maintain hash with indifferent access" do
+    test_hashes = [
+      [{ "foo" => "bar" }.with_indifferent_access, ["blah"]],
+      [{ "foo" => "bar" }.with_indifferent_access, []]
+    ]
+
+    test_hashes.each do |before_filter, filter_words|
+      parameter_filter = ActionDispatch::Http::ParameterFilter.new(filter_words)
+      assert_instance_of ActiveSupport::HashWithIndifferentAccess,
+                         parameter_filter.filter(before_filter)
+    end
+  end
+
   test "filtered_parameters returns params filtered" do
     request = stub_request(
-      'action_dispatch.request.parameters' => {
-        'lifo' => 'Pratik',
-        'amount' => '420',
-        'step' => '1'
+      "action_dispatch.request.parameters" => {
+        "lifo" => "Pratik",
+        "amount" => "420",
+        "step" => "1"
       },
-      'action_dispatch.parameter_filter' => [:lifo, :amount]
+      "action_dispatch.parameter_filter" => [:lifo, :amount]
     )
 
     params = request.filtered_parameters
@@ -1121,12 +1132,12 @@ class RequestParameterFilter < BaseRequestTest
 
   test "filtered_env filters env as a whole" do
     request = stub_request(
-      'action_dispatch.request.parameters' => {
-        'amount' => '420',
-        'step' => '1'
+      "action_dispatch.request.parameters" => {
+        "amount" => "420",
+        "step" => "1"
       },
       "RAW_POST_DATA" => "yada yada",
-      'action_dispatch.parameter_filter' => [:lifo, :amount]
+      "action_dispatch.parameter_filter" => [:lifo, :amount]
     )
     request = stub_request(request.filtered_env)
 
@@ -1138,9 +1149,9 @@ class RequestParameterFilter < BaseRequestTest
   test "filtered_path returns path with filtered query string" do
     %w(; &).each do |sep|
       request = stub_request(
-        'QUERY_STRING' => %w(username=sikachu secret=bd4f21f api_key=b1bc3b3cd352f68d79d7).join(sep),
-        'PATH_INFO' => '/authenticate',
-        'action_dispatch.parameter_filter' => [:secret, :api_key]
+        "QUERY_STRING" => %w(username=sikachu secret=bd4f21f api_key=b1bc3b3cd352f68d79d7).join(sep),
+        "PATH_INFO" => "/authenticate",
+        "action_dispatch.parameter_filter" => [:secret, :api_key]
       )
 
       path = request.filtered_path
@@ -1150,9 +1161,9 @@ class RequestParameterFilter < BaseRequestTest
 
   test "filtered_path should not unescape a genuine '[FILTERED]' value" do
     request = stub_request(
-      'QUERY_STRING' => "secret=bd4f21f&genuine=%5BFILTERED%5D",
-      'PATH_INFO' => '/authenticate',
-      'action_dispatch.parameter_filter' => [:secret]
+      "QUERY_STRING" => "secret=bd4f21f&genuine=%5BFILTERED%5D",
+      "PATH_INFO" => "/authenticate",
+      "action_dispatch.parameter_filter" => [:secret]
     )
 
     path = request.filtered_path
@@ -1161,9 +1172,9 @@ class RequestParameterFilter < BaseRequestTest
 
   test "filtered_path should preserve duplication of keys in query string" do
     request = stub_request(
-      'QUERY_STRING' => "username=sikachu&secret=bd4f21f&username=fxn",
-      'PATH_INFO' => '/authenticate',
-      'action_dispatch.parameter_filter' => [:secret]
+      "QUERY_STRING" => "username=sikachu&secret=bd4f21f&username=fxn",
+      "PATH_INFO" => "/authenticate",
+      "action_dispatch.parameter_filter" => [:secret]
     )
 
     path = request.filtered_path
@@ -1172,9 +1183,9 @@ class RequestParameterFilter < BaseRequestTest
 
   test "filtered_path should ignore searchparts" do
     request = stub_request(
-      'QUERY_STRING' => "secret",
-      'PATH_INFO' => '/authenticate',
-      'action_dispatch.parameter_filter' => [:secret]
+      "QUERY_STRING" => "secret",
+      "PATH_INFO" => "/authenticate",
+      "action_dispatch.parameter_filter" => [:secret]
     )
 
     path = request.filtered_path
@@ -1184,10 +1195,10 @@ end
 
 class RequestEtag < BaseRequestTest
   test "always matches *" do
-    request = stub_request('HTTP_IF_NONE_MATCH' => '*')
+    request = stub_request("HTTP_IF_NONE_MATCH" => "*")
 
-    assert_equal '*', request.if_none_match
-    assert_equal ['*'], request.if_none_match_etags
+    assert_equal "*", request.if_none_match
+    assert_equal ["*"], request.if_none_match_etags
 
     assert request.etag_matches?('"strong"')
     assert request.etag_matches?('W/"weak"')
@@ -1197,7 +1208,7 @@ class RequestEtag < BaseRequestTest
   test "doesn't match absent If-None-Match" do
     request = stub_request
 
-    assert_equal nil, request.if_none_match
+    assert_nil request.if_none_match
     assert_equal [], request.if_none_match_etags
 
     assert_not request.etag_matches?("foo")
@@ -1206,7 +1217,7 @@ class RequestEtag < BaseRequestTest
 
   test "matches opaque ETag validators without unquoting" do
     header = '"the-etag"'
-    request = stub_request('HTTP_IF_NONE_MATCH' => header)
+    request = stub_request("HTTP_IF_NONE_MATCH" => header)
 
     assert_equal header, request.if_none_match
     assert_equal ['"the-etag"'], request.if_none_match_etags
@@ -1217,8 +1228,8 @@ class RequestEtag < BaseRequestTest
 
   test "if_none_match_etags multiple" do
     header = 'etag1, etag2, "third etag", "etag4"'
-    expected = ['etag1', 'etag2', '"third etag"', '"etag4"']
-    request = stub_request('HTTP_IF_NONE_MATCH' => header)
+    expected = ["etag1", "etag2", '"third etag"', '"etag4"']
+    request = stub_request("HTTP_IF_NONE_MATCH" => header)
 
     assert_equal header, request.if_none_match
     assert_equal expected, request.if_none_match_etags
@@ -1234,7 +1245,7 @@ class RequestVariant < BaseRequestTest
     @request = stub_request
   end
 
-  test 'setting variant to a symbol' do
+  test "setting variant to a symbol" do
     @request.variant = :phone
 
     assert @request.variant.phone?
@@ -1243,7 +1254,7 @@ class RequestVariant < BaseRequestTest
     assert_not @request.variant.any?(:tablet, :desktop)
   end
 
-  test 'setting variant to an array of symbols' do
+  test "setting variant to an array of symbols" do
     @request.variant = [:phone, :tablet]
 
     assert @request.variant.phone?
@@ -1253,7 +1264,7 @@ class RequestVariant < BaseRequestTest
     assert_not @request.variant.any?(:desktop, :watch)
   end
 
-  test 'clearing variant' do
+  test "clearing variant" do
     @request.variant = nil
 
     assert @request.variant.empty?
@@ -1261,35 +1272,50 @@ class RequestVariant < BaseRequestTest
     assert_not @request.variant.any?(:phone, :tablet)
   end
 
-  test 'setting variant to a non-symbol value' do
+  test "setting variant to a non-symbol value" do
     assert_raise ArgumentError do
-      @request.variant = 'phone'
+      @request.variant = "phone"
     end
   end
 
-  test 'setting variant to an array containing a non-symbol value' do
+  test "setting variant to an array containing a non-symbol value" do
     assert_raise ArgumentError do
-      @request.variant = [:phone, 'tablet']
+      @request.variant = [:phone, "tablet"]
     end
   end
 end
 
 class RequestFormData < BaseRequestTest
-  test 'media_type is from the FORM_DATA_MEDIA_TYPES array' do
-    assert stub_request('CONTENT_TYPE' => 'application/x-www-form-urlencoded').form_data?
-    assert stub_request('CONTENT_TYPE' => 'multipart/form-data').form_data?
+  test "media_type is from the FORM_DATA_MEDIA_TYPES array" do
+    assert stub_request("CONTENT_TYPE" => "application/x-www-form-urlencoded").form_data?
+    assert stub_request("CONTENT_TYPE" => "multipart/form-data").form_data?
   end
 
-  test 'media_type is not from the FORM_DATA_MEDIA_TYPES array' do
-    assert !stub_request('CONTENT_TYPE' => 'application/xml').form_data?
-    assert !stub_request('CONTENT_TYPE' => 'multipart/related').form_data?
+  test "media_type is not from the FORM_DATA_MEDIA_TYPES array" do
+    assert !stub_request("CONTENT_TYPE" => "application/xml").form_data?
+    assert !stub_request("CONTENT_TYPE" => "multipart/related").form_data?
   end
 
-  test 'no Content-Type header is provided and the request_method is POST' do
-    request = stub_request('REQUEST_METHOD' => 'POST')
+  test "no Content-Type header is provided and the request_method is POST" do
+    request = stub_request("REQUEST_METHOD" => "POST")
 
-    assert_equal '', request.media_type
-    assert_equal 'POST', request.request_method
+    assert_equal "", request.media_type
+    assert_equal "POST", request.request_method
     assert !request.form_data?
   end
 end
+
+class EarlyHintsRequestTest < BaseRequestTest
+  def setup
+    super
+    @env["rack.early_hints"] = lambda { |links| links }
+    @request = stub_request
+  end
+
+  test "when early hints is set in the env link headers are sent" do
+    early_hints = @request.send_early_hints("Link" => "</style.css>; rel=preload; as=style\n</script.js>; rel=preload")
+    expected_hints = { "Link" => "</style.css>; rel=preload; as=style\n</script.js>; rel=preload" }
+
+    assert_equal expected_hints, early_hints
+  end
+end
diff --git a/actionpack/test/dispatch/response_test.rb b/actionpack/test/dispatch/response_test.rb
index aa90433505..4e350162c9 100644
--- a/actionpack/test/dispatch/response_test.rb
+++ b/actionpack/test/dispatch/response_test.rb
@@ -1,6 +1,8 @@
-require 'abstract_unit'
-require 'timeout'
-require 'rack/content_length'
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "timeout"
+require "rack/content_length"
 
 class ResponseTest < ActiveSupport::TestCase
   def setup
@@ -40,8 +42,8 @@ class ResponseTest < ActiveSupport::TestCase
   def test_each_isnt_called_if_str_body_is_written
     # Controller writes and reads response body
     each_counter = 0
-    @response.body = Object.new.tap {|o| o.singleton_class.send(:define_method, :each) { |&block| each_counter += 1; block.call 'foo' } }
-    @response['X-Foo'] = @response.body
+    @response.body = Object.new.tap { |o| o.singleton_class.send(:define_method, :each) { |&block| each_counter += 1; block.call "foo" } }
+    @response["X-Foo"] = @response.body
 
     assert_equal 1, each_counter, "#each was not called once"
 
@@ -49,7 +51,7 @@ class ResponseTest < ActiveSupport::TestCase
     status, headers, body = @response.to_a
 
     assert_equal 200, status
-    assert_equal "foo", headers['X-Foo']
+    assert_equal "foo", headers["X-Foo"]
     assert_equal "foo", body.each.to_a.join
 
     # Show that #each was not called twice
@@ -60,21 +62,21 @@ class ResponseTest < ActiveSupport::TestCase
     @response.body
 
     # set header after the action reads back @response.body
-    @response['x-header'] = "Best of all possible worlds."
+    @response["x-header"] = "Best of all possible worlds."
 
     # the response can be built.
     status, headers, body = @response.to_a
     assert_equal 200, status
     assert_equal "", body.body
 
-    assert_equal "Best of all possible worlds.", headers['x-header']
+    assert_equal "Best of all possible worlds.", headers["x-header"]
   end
 
   def test_read_body_during_action
     @response.body = "Hello, World!"
 
     # even though there's no explicitly set content-type,
-    assert_equal nil, @response.content_type
+    assert_nil @response.content_type
 
     # after the action reads back @response.body,
     assert_equal "Hello, World!", @response.body
@@ -99,15 +101,20 @@ class ResponseTest < ActiveSupport::TestCase
   end
 
   def test_response_charset_writer
-    @response.charset = 'utf-16'
-    assert_equal 'utf-16', @response.charset
+    @response.charset = "utf-16"
+    assert_equal "utf-16", @response.charset
     @response.charset = nil
-    assert_equal 'utf-8', @response.charset
+    assert_equal "utf-8", @response.charset
   end
 
   def test_setting_content_type_header_impacts_content_type_method
-    @response.headers['Content-Type'] = "application/aaron"
-    assert_equal 'application/aaron', @response.content_type
+    @response.headers["Content-Type"] = "application/aaron"
+    assert_equal "application/aaron", @response.content_type
+  end
+
+  def test_empty_content_type_returns_nil
+    @response.headers["Content-Type"] = ""
+    assert_nil @response.content_type
   end
 
   test "simple output" do
@@ -125,14 +132,14 @@ class ResponseTest < ActiveSupport::TestCase
   end
 
   test "status handled properly in initialize" do
-    assert_equal 200, ActionDispatch::Response.new('200 OK').status
+    assert_equal 200, ActionDispatch::Response.new("200 OK").status
   end
 
   def test_only_set_charset_still_defaults_to_text_html
     response = ActionDispatch::Response.new
     response.charset = "utf-16"
-    _,headers,_ = response.to_a
-    assert_equal "text/html; charset=utf-16", headers['Content-Type']
+    _, headers, _ = response.to_a
+    assert_equal "text/html; charset=utf-16", headers["Content-Type"]
   end
 
   test "utf8 output" do
@@ -145,6 +152,26 @@ class ResponseTest < ActiveSupport::TestCase
     }, headers)
   end
 
+  test "content length" do
+    [100, 101, 102, 204].each do |c|
+      @response = ActionDispatch::Response.new
+      @response.status = c.to_s
+      @response.set_header "Content-Length", "0"
+      _, headers, _ = @response.to_a
+      assert !headers.has_key?("Content-Length"), "#{c} must not have a Content-Length header field"
+    end
+  end
+
+  test "does not contain a message-body" do
+    [100, 101, 102, 204, 304].each do |c|
+      @response = ActionDispatch::Response.new
+      @response.status = c.to_s
+      @response.body = "Body must not be included"
+      _, _, body = @response.to_a
+      assert_empty body, "#{c} must not have a message-body but actually contains #{body}"
+    end
+  end
+
   test "content type" do
     [204, 304].each do |c|
       @response = ActionDispatch::Response.new
@@ -164,7 +191,7 @@ class ResponseTest < ActiveSupport::TestCase
   test "does not include Status header" do
     @response.status = "200 OK"
     _, headers, _ = @response.to_a
-    assert !headers.has_key?('Status')
+    assert !headers.has_key?("Status")
   end
 
   test "response code" do
@@ -201,32 +228,32 @@ class ResponseTest < ActiveSupport::TestCase
   end
 
   test "cookies" do
-    @response.set_cookie("user_name", :value => "david", :path => "/")
+    @response.set_cookie("user_name", value: "david", path: "/")
     _status, headers, _body = @response.to_a
     assert_equal "user_name=david; path=/", headers["Set-Cookie"]
-    assert_equal({"user_name" => "david"}, @response.cookies)
+    assert_equal({ "user_name" => "david" }, @response.cookies)
   end
 
   test "multiple cookies" do
-    @response.set_cookie("user_name", :value => "david", :path => "/")
-    @response.set_cookie("login", :value => "foo&bar", :path => "/", :expires => Time.utc(2005, 10, 10,5))
+    @response.set_cookie("user_name", value: "david", path: "/")
+    @response.set_cookie("login", value: "foo&bar", path: "/", expires: Time.utc(2005, 10, 10, 5))
     _status, headers, _body = @response.to_a
     assert_equal "user_name=david; path=/\nlogin=foo%26bar; path=/; expires=Mon, 10 Oct 2005 05:00:00 -0000", headers["Set-Cookie"]
-    assert_equal({"login" => "foo&bar", "user_name" => "david"}, @response.cookies)
+    assert_equal({ "login" => "foo&bar", "user_name" => "david" }, @response.cookies)
   end
 
   test "delete cookies" do
-    @response.set_cookie("user_name", :value => "david", :path => "/")
-    @response.set_cookie("login", :value => "foo&bar", :path => "/", :expires => Time.utc(2005, 10, 10,5))
+    @response.set_cookie("user_name", value: "david", path: "/")
+    @response.set_cookie("login", value: "foo&bar", path: "/", expires: Time.utc(2005, 10, 10, 5))
     @response.delete_cookie("login")
-    assert_equal({"user_name" => "david", "login" => nil}, @response.cookies)
+    assert_equal({ "user_name" => "david", "login" => nil }, @response.cookies)
   end
 
   test "read ETag and Cache-Control" do
     resp = ActionDispatch::Response.new.tap { |response|
       response.cache_control[:public] = true
-      response.etag = '123'
-      response.body = 'Hello'
+      response.etag = "123"
+      response.body = "Hello"
     }
     resp.to_a
 
@@ -234,17 +261,17 @@ class ResponseTest < ActiveSupport::TestCase
     assert resp.weak_etag?
     assert_not resp.strong_etag?
     assert_equal('W/"202cb962ac59075b964b07152d234b70"', resp.etag)
-    assert_equal({:public => true}, resp.cache_control)
+    assert_equal({ public: true }, resp.cache_control)
 
-    assert_equal('public', resp.headers['Cache-Control'])
-    assert_equal('W/"202cb962ac59075b964b07152d234b70"', resp.headers['ETag'])
+    assert_equal("public", resp.headers["Cache-Control"])
+    assert_equal('W/"202cb962ac59075b964b07152d234b70"', resp.headers["ETag"])
   end
 
   test "read strong ETag" do
     resp = ActionDispatch::Response.new.tap { |response|
       response.cache_control[:public] = true
-      response.strong_etag = '123'
-      response.body = 'Hello'
+      response.strong_etag = "123"
+      response.body = "Hello"
     }
     resp.to_a
 
@@ -256,55 +283,54 @@ class ResponseTest < ActiveSupport::TestCase
 
   test "read charset and content type" do
     resp = ActionDispatch::Response.new.tap { |response|
-      response.charset = 'utf-16'
+      response.charset = "utf-16"
       response.content_type = Mime[:xml]
-      response.body = 'Hello'
+      response.body = "Hello"
     }
     resp.to_a
 
-    assert_equal('utf-16', resp.charset)
+    assert_equal("utf-16", resp.charset)
     assert_equal(Mime[:xml], resp.content_type)
 
-    assert_equal('application/xml; charset=utf-16', resp.headers['Content-Type'])
+    assert_equal("application/xml; charset=utf-16", resp.headers["Content-Type"])
   end
 
   test "read content type with default charset utf-8" do
-    original = ActionDispatch::Response.default_charset
-    begin
-      resp = ActionDispatch::Response.new(200, { "Content-Type" => "text/xml" })
-      assert_equal('utf-8', resp.charset)
-    ensure
-      ActionDispatch::Response.default_charset = original
-    end
+    resp = ActionDispatch::Response.new(200, "Content-Type" => "text/xml")
+    assert_equal("utf-8", resp.charset)
   end
 
   test "read content type with charset utf-16" do
     original = ActionDispatch::Response.default_charset
     begin
-      ActionDispatch::Response.default_charset = 'utf-16'
-      resp = ActionDispatch::Response.new(200, { "Content-Type" => "text/xml" })
-      assert_equal('utf-16', resp.charset)
+      ActionDispatch::Response.default_charset = "utf-16"
+      resp = ActionDispatch::Response.new(200, "Content-Type" => "text/xml")
+      assert_equal("utf-16", resp.charset)
     ensure
       ActionDispatch::Response.default_charset = original
     end
   end
 
-  test "read x_frame_options, x_content_type_options and x_xss_protection" do
+  test "read x_frame_options, x_content_type_options, x_xss_protection, x_download_options and x_permitted_cross_domain_policies" do
     original_default_headers = ActionDispatch::Response.default_headers
     begin
       ActionDispatch::Response.default_headers = {
-        'X-Frame-Options' => 'DENY',
-        'X-Content-Type-Options' => 'nosniff',
-        'X-XSS-Protection' => '1;'
+        "X-Frame-Options" => "DENY",
+        "X-Content-Type-Options" => "nosniff",
+        "X-XSS-Protection" => "1;",
+        "X-Download-Options" => "noopen",
+        "X-Permitted-Cross-Domain-Policies" => "none"
       }
       resp = ActionDispatch::Response.create.tap { |response|
-        response.body = 'Hello'
+        response.body = "Hello"
       }
       resp.to_a
 
-      assert_equal('DENY', resp.headers['X-Frame-Options'])
-      assert_equal('nosniff', resp.headers['X-Content-Type-Options'])
-      assert_equal('1;', resp.headers['X-XSS-Protection'])
+      assert_equal("DENY", resp.headers["X-Frame-Options"])
+      assert_equal("nosniff", resp.headers["X-Content-Type-Options"])
+      assert_equal("1;", resp.headers["X-XSS-Protection"])
+      assert_equal("noopen", resp.headers["X-Download-Options"])
+      assert_equal("none", resp.headers["X-Permitted-Cross-Domain-Policies"])
     ensure
       ActionDispatch::Response.default_headers = original_default_headers
     end
@@ -314,14 +340,14 @@ class ResponseTest < ActiveSupport::TestCase
     original_default_headers = ActionDispatch::Response.default_headers
     begin
       ActionDispatch::Response.default_headers = {
-        'X-XX-XXXX' => 'Here is my phone number'
+        "X-XX-XXXX" => "Here is my phone number"
       }
       resp = ActionDispatch::Response.create.tap { |response|
-        response.body = 'Hello'
+        response.body = "Hello"
       }
       resp.to_a
 
-      assert_equal('Here is my phone number', resp.headers['X-XX-XXXX'])
+      assert_equal("Here is my phone number", resp.headers["X-XX-XXXX"])
     ensure
       ActionDispatch::Response.default_headers = original_default_headers
     end
@@ -333,13 +359,13 @@ class ResponseTest < ActiveSupport::TestCase
   end
 
   test "can be explicitly destructured into status, headers and an enumerable body" do
-    response = ActionDispatch::Response.new(404, { 'Content-Type' => 'text/plain' }, ['Not Found'])
+    response = ActionDispatch::Response.new(404, { "Content-Type" => "text/plain" }, ["Not Found"])
     response.request = ActionDispatch::Request.empty
     status, headers, body = *response
 
     assert_equal 404, status
-    assert_equal({ 'Content-Type' => 'text/plain' }, headers)
-    assert_equal ['Not Found'], body.each.to_a
+    assert_equal({ "Content-Type" => "text/plain" }, headers)
+    assert_equal ["Not Found"], body.each.to_a
   end
 
   test "[response.to_a].flatten does not recurse infinitely" do
@@ -352,74 +378,74 @@ class ResponseTest < ActiveSupport::TestCase
   end
 
   test "compatibility with Rack::ContentLength" do
-    @response.body = 'Hello'
+    @response.body = "Hello"
     app = lambda { |env| @response.to_a }
     env = Rack::MockRequest.env_for("/")
 
-    status, headers, body = app.call(env)
-    assert_nil headers['Content-Length']
+    _status, headers, _body = app.call(env)
+    assert_nil headers["Content-Length"]
 
-    status, headers, body = Rack::ContentLength.new(app).call(env)
-    assert_equal '5', headers['Content-Length']
+    _status, headers, _body = Rack::ContentLength.new(app).call(env)
+    assert_equal "5", headers["Content-Length"]
   end
 end
 
 class ResponseHeadersTest < ActiveSupport::TestCase
   def setup
     @response = ActionDispatch::Response.create
-    @response.set_header 'Foo', '1'
+    @response.set_header "Foo", "1"
   end
 
-  test 'has_header?' do
-    assert @response.has_header? 'Foo'
-    assert_not @response.has_header? 'foo'
+  test "has_header?" do
+    assert @response.has_header? "Foo"
+    assert_not @response.has_header? "foo"
     assert_not @response.has_header? nil
   end
 
-  test 'get_header' do
-    assert_equal '1', @response.get_header('Foo')
-    assert_nil @response.get_header('foo')
+  test "get_header" do
+    assert_equal "1", @response.get_header("Foo")
+    assert_nil @response.get_header("foo")
     assert_nil @response.get_header(nil)
   end
 
-  test 'set_header' do
-    assert_equal '2', @response.set_header('Foo', '2')
-    assert @response.has_header?('Foo')
-    assert_equal '2', @response.get_header('Foo')
+  test "set_header" do
+    assert_equal "2", @response.set_header("Foo", "2")
+    assert @response.has_header?("Foo")
+    assert_equal "2", @response.get_header("Foo")
 
-    assert_nil @response.set_header('Foo', nil)
-    assert @response.has_header?('Foo')
-    assert_nil @response.get_header('Foo')
+    assert_nil @response.set_header("Foo", nil)
+    assert @response.has_header?("Foo")
+    assert_nil @response.get_header("Foo")
   end
 
-  test 'delete_header' do
+  test "delete_header" do
     assert_nil @response.delete_header(nil)
 
-    assert_nil @response.delete_header('foo')
-    assert @response.has_header?('Foo')
+    assert_nil @response.delete_header("foo")
+    assert @response.has_header?("Foo")
 
-    assert_equal '1', @response.delete_header('Foo')
-    assert_not @response.has_header?('Foo')
+    assert_equal "1", @response.delete_header("Foo")
+    assert_not @response.has_header?("Foo")
   end
 
-  test 'add_header' do
+  test "add_header" do
     # Add a value to an existing header
-    assert_equal '1,2', @response.add_header('Foo', '2')
-    assert_equal '1,2', @response.get_header('Foo')
+    assert_equal "1,2", @response.add_header("Foo", "2")
+    assert_equal "1,2", @response.get_header("Foo")
 
     # Add nil to an existing header
-    assert_equal '1,2', @response.add_header('Foo', nil)
-    assert_equal '1,2', @response.get_header('Foo')
+    assert_equal "1,2", @response.add_header("Foo", nil)
+    assert_equal "1,2", @response.get_header("Foo")
 
     # Add nil to a nonexistent header
-    assert_nil @response.add_header('Bar', nil)
-    assert_not @response.has_header?('Bar')
-    assert_nil @response.get_header('Bar')
+    assert_nil @response.add_header("Bar", nil)
+    assert_not @response.has_header?("Bar")
+    assert_nil @response.get_header("Bar")
 
     # Add a value to a nonexistent header
-    assert_equal '1', @response.add_header('Bar', '1')
-    assert @response.has_header?('Bar')
-    assert_equal '1', @response.get_header('Bar')
+    assert_equal "1", @response.add_header("Bar", "1")
+    assert @response.has_header?("Bar")
+    assert_equal "1", @response.get_header("Bar")
   end
 end
 
@@ -428,87 +454,87 @@ class ResponseIntegrationTest < ActionDispatch::IntegrationTest
     @app = lambda { |env|
       ActionDispatch::Response.new.tap { |resp|
         resp.cache_control[:public] = true
-        resp.etag = '123'
-        resp.body = 'Hello'
+        resp.etag = "123"
+        resp.body = "Hello"
         resp.request = ActionDispatch::Request.empty
       }.to_a
     }
 
-    get '/'
+    get "/"
     assert_response :success
 
-    assert_equal('public', @response.headers['Cache-Control'])
-    assert_equal('W/"202cb962ac59075b964b07152d234b70"', @response.headers['ETag'])
+    assert_equal("public", @response.headers["Cache-Control"])
+    assert_equal('W/"202cb962ac59075b964b07152d234b70"', @response.headers["ETag"])
 
     assert_equal('W/"202cb962ac59075b964b07152d234b70"', @response.etag)
-    assert_equal({:public => true}, @response.cache_control)
+    assert_equal({ public: true }, @response.cache_control)
   end
 
   test "response cache control from rackish app" do
     @app = lambda { |env|
       [200,
-        {'ETag' => 'W/"202cb962ac59075b964b07152d234b70"',
-          'Cache-Control' => 'public'}, ['Hello']]
+        { "ETag" => 'W/"202cb962ac59075b964b07152d234b70"',
+          "Cache-Control" => "public" }, ["Hello"]]
     }
 
-    get '/'
+    get "/"
     assert_response :success
 
-    assert_equal('public', @response.headers['Cache-Control'])
-    assert_equal('W/"202cb962ac59075b964b07152d234b70"', @response.headers['ETag'])
+    assert_equal("public", @response.headers["Cache-Control"])
+    assert_equal('W/"202cb962ac59075b964b07152d234b70"', @response.headers["ETag"])
 
     assert_equal('W/"202cb962ac59075b964b07152d234b70"', @response.etag)
-    assert_equal({:public => true}, @response.cache_control)
+    assert_equal({ public: true }, @response.cache_control)
   end
 
   test "response charset and content type from railsish app" do
     @app = lambda { |env|
       ActionDispatch::Response.new.tap { |resp|
-        resp.charset = 'utf-16'
+        resp.charset = "utf-16"
         resp.content_type = Mime[:xml]
-        resp.body = 'Hello'
+        resp.body = "Hello"
         resp.request = ActionDispatch::Request.empty
       }.to_a
     }
 
-    get '/'
+    get "/"
     assert_response :success
 
-    assert_equal('utf-16', @response.charset)
+    assert_equal("utf-16", @response.charset)
     assert_equal(Mime[:xml], @response.content_type)
 
-    assert_equal('application/xml; charset=utf-16', @response.headers['Content-Type'])
+    assert_equal("application/xml; charset=utf-16", @response.headers["Content-Type"])
   end
 
   test "response charset and content type from rackish app" do
     @app = lambda { |env|
       [200,
-        {'Content-Type' => 'application/xml; charset=utf-16'},
-        ['Hello']]
+        { "Content-Type" => "application/xml; charset=utf-16" },
+        ["Hello"]]
     }
 
-    get '/'
+    get "/"
     assert_response :success
 
-    assert_equal('utf-16', @response.charset)
+    assert_equal("utf-16", @response.charset)
     assert_equal(Mime[:xml], @response.content_type)
 
-    assert_equal('application/xml; charset=utf-16', @response.headers['Content-Type'])
+    assert_equal("application/xml; charset=utf-16", @response.headers["Content-Type"])
   end
 
   test "strong ETag validator" do
     @app = lambda { |env|
       ActionDispatch::Response.new.tap { |resp|
-        resp.strong_etag = '123'
-        resp.body = 'Hello'
+        resp.strong_etag = "123"
+        resp.body = "Hello"
         resp.request = ActionDispatch::Request.empty
       }.to_a
     }
 
-    get '/'
+    get "/"
     assert_response :ok
 
-    assert_equal('"202cb962ac59075b964b07152d234b70"', @response.headers['ETag'])
+    assert_equal('"202cb962ac59075b964b07152d234b70"', @response.headers["ETag"])
     assert_equal('"202cb962ac59075b964b07152d234b70"', @response.etag)
   end
 end
diff --git a/actionpack/test/dispatch/routing/concerns_test.rb b/actionpack/test/dispatch/routing/concerns_test.rb
index 6934271846..503a7ccd56 100644
--- a/actionpack/test/dispatch/routing/concerns_test.rb
+++ b/actionpack/test/dispatch/routing/concerns_test.rb
@@ -1,4 +1,6 @@
-require 'abstract_unit'
+# frozen_string_literal: true
+
+require "abstract_unit"
 
 class ReviewsController < ResourcesController; end
 
diff --git a/actionpack/test/dispatch/routing/custom_url_helpers_test.rb b/actionpack/test/dispatch/routing/custom_url_helpers_test.rb
new file mode 100644
index 0000000000..a1a1e79884
--- /dev/null
+++ b/actionpack/test/dispatch/routing/custom_url_helpers_test.rb
@@ -0,0 +1,333 @@
+# frozen_string_literal: true
+
+require "abstract_unit"
+
+class TestCustomUrlHelpers < ActionDispatch::IntegrationTest
+  class Linkable
+    attr_reader :id
+
+    def self.name
+      super.demodulize
+    end
+
+    def initialize(id)
+      @id = id
+    end
+
+    def linkable_type
+      self.class.name.underscore
+    end
+  end
+
+  class Category < Linkable; end
+  class Collection < Linkable; end
+  class Product < Linkable; end
+  class Manufacturer < Linkable; end
+
+  class Model
+    extend ActiveModel::Naming
+    include ActiveModel::Conversion
+
+    attr_reader :id
+
+    def initialize(id = nil)
+      @id = id
+    end
+
+    remove_method :model_name
+    def model_name
+      @_model_name ||= ActiveModel::Name.new(self.class, nil, self.class.name.demodulize)
+    end
+
+    def persisted?
+      false
+    end
+  end
+
+  class Basket < Model; end
+  class User < Model; end
+  class Video < Model; end
+
+  class Article
+    attr_reader :id
+
+    def self.name
+      "Article"
+    end
+
+    def initialize(id)
+      @id = id
+    end
+  end
+
+  class Page
+    attr_reader :id
+
+    def self.name
+      super.demodulize
+    end
+
+    def initialize(id)
+      @id = id
+    end
+  end
+
+  class CategoryPage < Page; end
+  class ProductPage < Page; end
+
+  Routes = ActionDispatch::Routing::RouteSet.new
+  Routes.draw do
+    default_url_options host: "www.example.com"
+
+    root to: "pages#index"
+    get "/basket", to: "basket#show", as: :basket
+    get "/posts/:id", to: "posts#show", as: :post
+    get "/profile", to: "users#profile", as: :profile
+    get "/media/:id", to: "media#show", as: :media
+    get "/pages/:id", to: "pages#show", as: :page
+
+    resources :categories, :collections, :products, :manufacturers
+
+    namespace :admin do
+      get "/dashboard", to: "dashboard#index"
+    end
+
+    direct(:website)  { "http://www.rubyonrails.org" }
+    direct("string")  { "http://www.rubyonrails.org" }
+    direct(:helper)   { basket_url }
+    direct(:linkable) { |linkable| [:"#{linkable.linkable_type}", { id: linkable.id }] }
+    direct(:nested)   { |linkable| route_for(:linkable, linkable) }
+    direct(:params)   { |params| params }
+    direct(:symbol)   { :basket }
+    direct(:hash)     { { controller: "basket", action: "show" } }
+    direct(:array)    { [:admin, :dashboard] }
+    direct(:options)  { |options| [:products, options] }
+    direct(:defaults, size: 10) { |options| [:products, options] }
+
+    direct(:browse, page: 1, size: 10) do |options|
+      [:products, options.merge(params.permit(:page, :size).to_h.symbolize_keys)]
+    end
+
+    resolve("Article") { |article| [:post, { id: article.id }] }
+    resolve("Basket") { |basket| [:basket] }
+    resolve("Manufacturer") { |manufacturer| route_for(:linkable, manufacturer) }
+    resolve("User", anchor: "details") { |user, options| [:profile, options] }
+    resolve("Video") { |video| [:media, { id: video.id }] }
+    resolve(%w[Page CategoryPage ProductPage]) { |page| [:page, { id: page.id }] }
+  end
+
+  APP = build_app Routes
+
+  def app
+    APP
+  end
+
+  include Routes.url_helpers
+
+  def setup
+    @category = Category.new("1")
+    @collection = Collection.new("2")
+    @product = Product.new("3")
+    @manufacturer = Manufacturer.new("apple")
+    @basket = Basket.new
+    @user = User.new
+    @video = Video.new("4")
+    @article = Article.new("5")
+    @page = Page.new("6")
+    @category_page = CategoryPage.new("7")
+    @product_page = ProductPage.new("8")
+    @path_params = { "controller" => "pages", "action" => "index" }
+    @unsafe_params = ActionController::Parameters.new(@path_params)
+    @safe_params = ActionController::Parameters.new(@path_params).permit(:controller, :action)
+  end
+
+  def params
+    ActionController::Parameters.new(page: 2, size: 25)
+  end
+
+  def test_direct_paths
+    assert_equal "/", website_path
+    assert_equal "/", Routes.url_helpers.website_path
+
+    assert_equal "/", string_path
+    assert_equal "/", Routes.url_helpers.string_path
+
+    assert_equal "/basket", helper_path
+    assert_equal "/basket", Routes.url_helpers.helper_path
+
+    assert_equal "/categories/1", linkable_path(@category)
+    assert_equal "/categories/1", Routes.url_helpers.linkable_path(@category)
+    assert_equal "/collections/2", linkable_path(@collection)
+    assert_equal "/collections/2", Routes.url_helpers.linkable_path(@collection)
+    assert_equal "/products/3", linkable_path(@product)
+    assert_equal "/products/3", Routes.url_helpers.linkable_path(@product)
+
+    assert_equal "/categories/1", nested_path(@category)
+    assert_equal "/categories/1", Routes.url_helpers.nested_path(@category)
+
+    assert_equal "/", params_path(@safe_params)
+    assert_equal "/", Routes.url_helpers.params_path(@safe_params)
+    assert_raises(ActionController::UnfilteredParameters) { params_path(@unsafe_params) }
+    assert_raises(ActionController::UnfilteredParameters) { Routes.url_helpers.params_path(@unsafe_params) }
+
+    assert_equal "/basket", symbol_path
+    assert_equal "/basket", Routes.url_helpers.symbol_path
+    assert_equal "/basket", hash_path
+    assert_equal "/basket", Routes.url_helpers.hash_path
+    assert_equal "/admin/dashboard", array_path
+    assert_equal "/admin/dashboard", Routes.url_helpers.array_path
+
+    assert_equal "/products?page=2", options_path(page: 2)
+    assert_equal "/products?page=2", Routes.url_helpers.options_path(page: 2)
+    assert_equal "/products?size=10", defaults_path
+    assert_equal "/products?size=10", Routes.url_helpers.defaults_path
+    assert_equal "/products?size=20", defaults_path(size: 20)
+    assert_equal "/products?size=20", Routes.url_helpers.defaults_path(size: 20)
+
+    assert_equal "/products?page=2&size=25", browse_path
+    assert_raises(NameError) { Routes.url_helpers.browse_path }
+  end
+
+  def test_direct_urls
+    assert_equal "http://www.rubyonrails.org", website_url
+    assert_equal "http://www.rubyonrails.org", Routes.url_helpers.website_url
+
+    assert_equal "http://www.rubyonrails.org", string_url
+    assert_equal "http://www.rubyonrails.org", Routes.url_helpers.string_url
+
+    assert_equal "http://www.example.com/basket", helper_url
+    assert_equal "http://www.example.com/basket", Routes.url_helpers.helper_url
+
+    assert_equal "http://www.example.com/categories/1", linkable_url(@category)
+    assert_equal "http://www.example.com/categories/1", Routes.url_helpers.linkable_url(@category)
+    assert_equal "http://www.example.com/collections/2", linkable_url(@collection)
+    assert_equal "http://www.example.com/collections/2", Routes.url_helpers.linkable_url(@collection)
+    assert_equal "http://www.example.com/products/3", linkable_url(@product)
+    assert_equal "http://www.example.com/products/3", Routes.url_helpers.linkable_url(@product)
+
+    assert_equal "http://www.example.com/categories/1", nested_url(@category)
+    assert_equal "http://www.example.com/categories/1", Routes.url_helpers.nested_url(@category)
+
+    assert_equal "http://www.example.com/", params_url(@safe_params)
+    assert_equal "http://www.example.com/", Routes.url_helpers.params_url(@safe_params)
+    assert_raises(ActionController::UnfilteredParameters) { params_url(@unsafe_params) }
+    assert_raises(ActionController::UnfilteredParameters) { Routes.url_helpers.params_url(@unsafe_params) }
+
+    assert_equal "http://www.example.com/basket", symbol_url
+    assert_equal "http://www.example.com/basket", Routes.url_helpers.symbol_url
+    assert_equal "http://www.example.com/basket", hash_url
+    assert_equal "http://www.example.com/basket", Routes.url_helpers.hash_url
+    assert_equal "http://www.example.com/admin/dashboard", array_url
+    assert_equal "http://www.example.com/admin/dashboard", Routes.url_helpers.array_url
+
+    assert_equal "http://www.example.com/products?page=2", options_url(page: 2)
+    assert_equal "http://www.example.com/products?page=2", Routes.url_helpers.options_url(page: 2)
+    assert_equal "http://www.example.com/products?size=10", defaults_url
+    assert_equal "http://www.example.com/products?size=10", Routes.url_helpers.defaults_url
+    assert_equal "http://www.example.com/products?size=20", defaults_url(size: 20)
+    assert_equal "http://www.example.com/products?size=20", Routes.url_helpers.defaults_url(size: 20)
+
+    assert_equal "http://www.example.com/products?page=2&size=25", browse_url
+    assert_raises(NameError) { Routes.url_helpers.browse_url }
+  end
+
+  def test_resolve_paths
+    assert_equal "/basket", polymorphic_path(@basket)
+    assert_equal "/basket", Routes.url_helpers.polymorphic_path(@basket)
+
+    assert_equal "/profile#details", polymorphic_path(@user)
+    assert_equal "/profile#details", Routes.url_helpers.polymorphic_path(@user)
+
+    assert_equal "/profile#password", polymorphic_path(@user, anchor: "password")
+    assert_equal "/profile#password", Routes.url_helpers.polymorphic_path(@user, anchor: "password")
+
+    assert_equal "/media/4", polymorphic_path(@video)
+    assert_equal "/media/4", Routes.url_helpers.polymorphic_path(@video)
+    assert_equal "/media/4", ActionDispatch::Routing::PolymorphicRoutes::HelperMethodBuilder.path.handle_model_call(self, @video)
+
+    assert_equal "/posts/5", polymorphic_path(@article)
+    assert_equal "/posts/5", Routes.url_helpers.polymorphic_path(@article)
+    assert_equal "/posts/5", ActionDispatch::Routing::PolymorphicRoutes::HelperMethodBuilder.path.handle_model_call(self, @article)
+
+    assert_equal "/pages/6", polymorphic_path(@page)
+    assert_equal "/pages/6", Routes.url_helpers.polymorphic_path(@page)
+    assert_equal "/pages/6", ActionDispatch::Routing::PolymorphicRoutes::HelperMethodBuilder.path.handle_model_call(self, @page)
+
+    assert_equal "/pages/7", polymorphic_path(@category_page)
+    assert_equal "/pages/7", Routes.url_helpers.polymorphic_path(@category_page)
+    assert_equal "/pages/7", ActionDispatch::Routing::PolymorphicRoutes::HelperMethodBuilder.path.handle_model_call(self, @category_page)
+
+    assert_equal "/pages/8", polymorphic_path(@product_page)
+    assert_equal "/pages/8", Routes.url_helpers.polymorphic_path(@product_page)
+    assert_equal "/pages/8", ActionDispatch::Routing::PolymorphicRoutes::HelperMethodBuilder.path.handle_model_call(self, @product_page)
+
+    assert_equal "/manufacturers/apple", polymorphic_path(@manufacturer)
+    assert_equal "/manufacturers/apple", Routes.url_helpers.polymorphic_path(@manufacturer)
+  end
+
+  def test_resolve_urls
+    assert_equal "http://www.example.com/basket", polymorphic_url(@basket)
+    assert_equal "http://www.example.com/basket", Routes.url_helpers.polymorphic_url(@basket)
+    assert_equal "http://www.example.com/basket", polymorphic_url(@basket)
+    assert_equal "http://www.example.com/basket", Routes.url_helpers.polymorphic_url(@basket)
+
+    assert_equal "http://www.example.com/profile#details", polymorphic_url(@user)
+    assert_equal "http://www.example.com/profile#details", Routes.url_helpers.polymorphic_url(@user)
+
+    assert_equal "http://www.example.com/profile#password", polymorphic_url(@user, anchor: "password")
+    assert_equal "http://www.example.com/profile#password", Routes.url_helpers.polymorphic_url(@user, anchor: "password")
+
+    assert_equal "http://www.example.com/media/4", polymorphic_url(@video)
+    assert_equal "http://www.example.com/media/4", Routes.url_helpers.polymorphic_url(@video)
+    assert_equal "http://www.example.com/media/4", ActionDispatch::Routing::PolymorphicRoutes::HelperMethodBuilder.url.handle_model_call(self, @video)
+
+    assert_equal "http://www.example.com/posts/5", polymorphic_url(@article)
+    assert_equal "http://www.example.com/posts/5", Routes.url_helpers.polymorphic_url(@article)
+    assert_equal "http://www.example.com/posts/5", ActionDispatch::Routing::PolymorphicRoutes::HelperMethodBuilder.url.handle_model_call(self, @article)
+
+    assert_equal "http://www.example.com/pages/6", polymorphic_url(@page)
+    assert_equal "http://www.example.com/pages/6", Routes.url_helpers.polymorphic_url(@page)
+    assert_equal "http://www.example.com/pages/6", ActionDispatch::Routing::PolymorphicRoutes::HelperMethodBuilder.url.handle_model_call(self, @page)
+
+    assert_equal "http://www.example.com/pages/7", polymorphic_url(@category_page)
+    assert_equal "http://www.example.com/pages/7", Routes.url_helpers.polymorphic_url(@category_page)
+    assert_equal "http://www.example.com/pages/7", ActionDispatch::Routing::PolymorphicRoutes::HelperMethodBuilder.url.handle_model_call(self, @category_page)
+
+    assert_equal "http://www.example.com/pages/8", polymorphic_url(@product_page)
+    assert_equal "http://www.example.com/pages/8", Routes.url_helpers.polymorphic_url(@product_page)
+    assert_equal "http://www.example.com/pages/8", ActionDispatch::Routing::PolymorphicRoutes::HelperMethodBuilder.url.handle_model_call(self, @product_page)
+
+    assert_equal "http://www.example.com/manufacturers/apple", polymorphic_url(@manufacturer)
+    assert_equal "http://www.example.com/manufacturers/apple", Routes.url_helpers.polymorphic_url(@manufacturer)
+  end
+
+  def test_defining_direct_inside_a_scope_raises_runtime_error
+    routes = ActionDispatch::Routing::RouteSet.new
+
+    assert_raises RuntimeError do
+      routes.draw do
+        namespace :admin do
+          direct(:rubyonrails) { "http://www.rubyonrails.org" }
+        end
+      end
+    end
+  end
+
+  def test_defining_resolve_inside_a_scope_raises_runtime_error
+    routes = ActionDispatch::Routing::RouteSet.new
+
+    assert_raises RuntimeError do
+      routes.draw do
+        namespace :admin do
+          resolve("User") { "/profile" }
+        end
+      end
+    end
+  end
+
+  def test_defining_direct_url_registers_helper_method
+    assert_equal "http://www.example.com/basket", Routes.url_helpers.symbol_url
+    assert_equal true, Routes.named_routes.route_defined?(:symbol_url), "'symbol_url' named helper not found"
+    assert_equal true, Routes.named_routes.route_defined?(:symbol_path), "'symbol_path' named helper not found"
+  end
+end
diff --git a/actionpack/test/dispatch/routing/inspector_test.rb b/actionpack/test/dispatch/routing/inspector_test.rb
index 5aafcb23c2..438a918567 100644
--- a/actionpack/test/dispatch/routing/inspector_test.rb
+++ b/actionpack/test/dispatch/routing/inspector_test.rb
@@ -1,6 +1,8 @@
-require 'abstract_unit'
-require 'rails/engine'
-require 'action_dispatch/routing/inspector'
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "rails/engine"
+require "action_dispatch/routing/inspector"
 
 class MountedRackApp
   def self.call(env)
@@ -30,11 +32,11 @@ module ActionDispatch
           end
         end
         engine.routes.draw do
-          get '/cart', :to => 'cart#show'
+          get "/cart", to: "cart#show"
         end
 
         output = draw do
-          get '/custom/assets', :to => 'custom_assets#show'
+          get "/custom/assets", to: "custom_assets#show"
           mount engine => "/blog", :as => "blog"
         end
 
@@ -71,7 +73,7 @@ module ActionDispatch
 
       def test_cart_inspect
         output = draw do
-          get '/cart', :to => 'cart#show'
+          get "/cart", to: "cart#show"
         end
 
         assert_equal [
@@ -82,7 +84,7 @@ module ActionDispatch
 
       def test_articles_inspect_with_multiple_verbs
         output = draw do
-          match 'articles/:id', to: 'articles#update', via: [:put, :patch]
+          match "articles/:id", to: "articles#update", via: [:put, :patch]
         end
 
         assert_equal [
@@ -93,7 +95,7 @@ module ActionDispatch
 
       def test_inspect_shows_custom_assets
         output = draw do
-          get '/custom/assets', :to => 'custom_assets#show'
+          get "/custom/assets", to: "custom_assets#show"
         end
 
         assert_equal [
@@ -122,7 +124,7 @@ module ActionDispatch
 
       def test_inspect_routes_shows_root_route
         output = draw do
-          root :to => 'pages#main'
+          root to: "pages#main"
         end
 
         assert_equal [
@@ -134,7 +136,7 @@ module ActionDispatch
       def test_inspect_routes_shows_dynamic_action_route
         output = draw do
           ActiveSupport::Deprecation.silence do
-            get 'api/:action' => 'api'
+            get "api/:action" => "api"
           end
         end
 
@@ -147,7 +149,7 @@ module ActionDispatch
       def test_inspect_routes_shows_controller_and_action_only_route
         output = draw do
           ActiveSupport::Deprecation.silence do
-            get ':controller/:action'
+            get ":controller/:action"
           end
         end
 
@@ -160,7 +162,7 @@ module ActionDispatch
       def test_inspect_routes_shows_controller_and_action_route_with_constraints
         output = draw do
           ActiveSupport::Deprecation.silence do
-            get ':controller(/:action(/:id))', :id => /\d+/
+            get ":controller(/:action(/:id))", id: /\d+/
           end
         end
 
@@ -172,18 +174,18 @@ module ActionDispatch
 
       def test_rails_routes_shows_route_with_defaults
         output = draw do
-          get 'photos/:id' => 'photos#show', :defaults => {:format => 'jpg'}
+          get "photos/:id" => "photos#show", :defaults => { format: "jpg" }
         end
 
         assert_equal [
           "Prefix Verb URI Pattern           Controller#Action",
-          %Q[       GET  /photos/:id(.:format) photos#show {:format=>"jpg"}]
+          '       GET  /photos/:id(.:format) photos#show {:format=>"jpg"}'
         ], output
       end
 
       def test_rails_routes_shows_route_with_constraints
         output = draw do
-          get 'photos/:id' => 'photos#show', :id => /[A-Z]\d{5}/
+          get "photos/:id" => "photos#show", :id => /[A-Z]\d{5}/
         end
 
         assert_equal [
@@ -194,13 +196,13 @@ module ActionDispatch
 
       def test_rails_routes_shows_routes_with_dashes
         output = draw do
-          get 'about-us' => 'pages#about_us'
-          get 'our-work/latest'
+          get "about-us" => "pages#about_us"
+          get "our-work/latest"
 
           resources :photos, only: [:show] do
-            get 'user-favorites', on: :collection
-            get 'preview-photo', on: :member
-            get 'summary-text'
+            get "user-favorites", on: :collection
+            get "preview-photo", on: :member
+            get "summary-text"
           end
         end
 
@@ -217,7 +219,7 @@ module ActionDispatch
 
       def test_rails_routes_shows_route_with_rack_app
         output = draw do
-          get 'foo/:id' => MountedRackApp, :id => /[A-Z]\d{5}/
+          get "foo/:id" => MountedRackApp, :id => /[A-Z]\d{5}/
         end
 
         assert_equal [
@@ -228,7 +230,7 @@ module ActionDispatch
 
       def test_rails_routes_shows_named_route_with_mounted_rack_app
         output = draw do
-          mount MountedRackApp => '/foo'
+          mount MountedRackApp => "/foo"
         end
 
         assert_equal [
@@ -239,7 +241,7 @@ module ActionDispatch
 
       def test_rails_routes_shows_overridden_named_route_with_mounted_rack_app_with_name
         output = draw do
-          mount MountedRackApp => '/foo', as: 'blog'
+          mount MountedRackApp => "/foo", as: "blog"
         end
 
         assert_equal [
@@ -256,8 +258,8 @@ module ActionDispatch
         end
 
         output = draw do
-          scope :constraint => constraint.new do
-            mount MountedRackApp => '/foo'
+          scope constraint: constraint.new do
+            mount MountedRackApp => "/foo"
           end
         end
 
@@ -269,7 +271,7 @@ module ActionDispatch
 
       def test_rails_routes_dont_show_app_mounted_in_assets_prefix
         output = draw do
-          get '/sprockets' => MountedRackApp
+          get "/sprockets" => MountedRackApp
         end
         assert_no_match(/MountedRackApp/, output.first)
         assert_no_match(/\/sprockets/, output.first)
@@ -277,8 +279,8 @@ module ActionDispatch
 
       def test_rails_routes_shows_route_defined_in_under_assets_prefix
         output = draw do
-          scope '/sprockets' do
-            get '/foo' => 'foo#bar'
+          scope "/sprockets" do
+            get "/foo" => "foo#bar"
           end
         end
         assert_equal [
@@ -289,9 +291,9 @@ module ActionDispatch
 
       def test_redirect
         output = draw do
-          get "/foo"    => redirect("/foo/bar"), :constraints => { :subdomain => "admin" }
+          get "/foo"    => redirect("/foo/bar"), :constraints => { subdomain: "admin" }
           get "/bar"    => redirect(path: "/foo/bar", status: 307)
-          get "/foobar" => redirect{ "/foo/bar" }
+          get "/foobar" => redirect { "/foo/bar" }
         end
 
         assert_equal [
@@ -303,7 +305,7 @@ module ActionDispatch
       end
 
       def test_routes_can_be_filtered
-        output = draw('posts') do
+        output = draw("posts") do
           resources :articles
           resources :posts
         end
@@ -320,7 +322,7 @@ module ActionDispatch
       end
 
       def test_routes_can_be_filtered_with_namespaced_controllers
-        output = draw('admin/posts') do
+        output = draw("admin/posts") do
           resources :articles
           namespace :admin do
             resources :posts
@@ -338,11 +340,10 @@ module ActionDispatch
                       "                DELETE /admin/posts/:id(.:format)      admin/posts#destroy"], output
       end
 
-
       def test_regression_route_with_controller_regexp
         output = draw do
           ActiveSupport::Deprecation.silence do
-            get ':controller(/:action)', controller: /api\/[^\/]+/, format: false
+            get ":controller(/:action)", controller: /api\/[^\/]+/, format: false
           end
         end
 
@@ -354,7 +355,7 @@ module ActionDispatch
         @set = ActionDispatch::Routing::RouteSet.new
 
         output = draw do
-          get '/cart', to: 'cart#show'
+          get "/cart", to: "cart#show"
         end
 
         assert_equal [
@@ -364,8 +365,8 @@ module ActionDispatch
       end
 
       def test_routes_with_undefined_filter
-        output = draw(controller: 'Rails::MissingController') do
-          get 'photos/:id' => 'photos#show', :id => /[A-Z]\d{5}/
+        output = draw(controller: "Rails::MissingController") do
+          get "photos/:id" => "photos#show", :id => /[A-Z]\d{5}/
         end
 
         assert_equal [
@@ -375,8 +376,8 @@ module ActionDispatch
       end
 
       def test_no_routes_matched_filter
-        output = draw('rails/dummy') do
-          get 'photos/:id' => 'photos#show', :id => /[A-Z]\d{5}/
+        output = draw("rails/dummy") do
+          get "photos/:id" => "photos#show", :id => /[A-Z]\d{5}/
         end
 
         assert_equal [
@@ -386,7 +387,7 @@ module ActionDispatch
       end
 
       def test_no_routes_were_defined
-        output = draw('Rails::DummyController') {}
+        output = draw("Rails::DummyController") {}
 
         assert_equal [
           "You don't have any routes defined!",
@@ -404,13 +405,13 @@ module ActionDispatch
           end
         end
         engine.routes.draw do
-          get '/cart', to: 'cart#show'
-          post '/cart', to: 'cart#create'
-          patch '/cart', to: 'cart#update'
+          get "/cart", to: "cart#show"
+          post "/cart", to: "cart#create"
+          patch "/cart", to: "cart#update"
         end
 
         output = draw do
-          get '/custom/assets', to: 'custom_assets#show'
+          get "/custom/assets", to: "custom_assets#show"
           mount engine => "/blog", as: "blog", internal: true
         end
 
@@ -419,7 +420,6 @@ module ActionDispatch
           "custom_assets GET  /custom/assets(.:format) custom_assets#show",
         ], output
       end
-
     end
   end
 end
diff --git a/actionpack/test/dispatch/routing/ipv6_redirect_test.rb b/actionpack/test/dispatch/routing/ipv6_redirect_test.rb
index f1b2e8cfc7..31559bffc7 100644
--- a/actionpack/test/dispatch/routing/ipv6_redirect_test.rb
+++ b/actionpack/test/dispatch/routing/ipv6_redirect_test.rb
@@ -1,4 +1,6 @@
-require 'abstract_unit'
+# frozen_string_literal: true
+
+require "abstract_unit"
 
 class IPv6IntegrationTest < ActionDispatch::IntegrationTest
   Routes = ActionDispatch::Routing::RouteSet.new
@@ -7,17 +9,17 @@ class IPv6IntegrationTest < ActionDispatch::IntegrationTest
   class ::BadRouteRequestController < ActionController::Base
     include Routes.url_helpers
     def index
-      render :text => foo_path
+      render plain: foo_path
     end
 
     def foo
-      redirect_to :action => :index
+      redirect_to action: :index
     end
   end
 
   Routes.draw do
-    get "/",    :to => 'bad_route_request#index', :as => :index
-    get "/foo", :to => "bad_route_request#foo", :as => :foo
+    get "/",    to: "bad_route_request#index", as: :index
+    get "/foo", to: "bad_route_request#foo", as: :foo
   end
 
   def _routes
@@ -32,14 +34,13 @@ class IPv6IntegrationTest < ActionDispatch::IntegrationTest
   test "bad IPv6 redirection" do
     #   def test_simple_redirect
     request_env = {
-      'REMOTE_ADDR' => 'fd07:2fa:6cff:2112:225:90ff:fec7:22aa',
-      'HTTP_HOST'   => '[fd07:2fa:6cff:2112:225:90ff:fec7:22aa]:3000',
-      'SERVER_NAME' => '[fd07:2fa:6cff:2112:225:90ff:fec7:22aa]',
-      'SERVER_PORT' => 3000 }
+      "REMOTE_ADDR" => "fd07:2fa:6cff:2112:225:90ff:fec7:22aa",
+      "HTTP_HOST"   => "[fd07:2fa:6cff:2112:225:90ff:fec7:22aa]:3000",
+      "SERVER_NAME" => "[fd07:2fa:6cff:2112:225:90ff:fec7:22aa]",
+      "SERVER_PORT" => 3000 }
 
-    get '/foo', env: request_env
+    get "/foo", env: request_env
     assert_response :redirect
-    assert_equal 'http://[fd07:2fa:6cff:2112:225:90ff:fec7:22aa]:3000/', redirect_to_url
+    assert_equal "http://[fd07:2fa:6cff:2112:225:90ff:fec7:22aa]:3000/", redirect_to_url
   end
-
 end
diff --git a/actionpack/test/dispatch/routing/route_set_test.rb b/actionpack/test/dispatch/routing/route_set_test.rb
index 9327fe12c6..e61d47b160 100644
--- a/actionpack/test/dispatch/routing/route_set_test.rb
+++ b/actionpack/test/dispatch/routing/route_set_test.rb
@@ -1,4 +1,6 @@
-require 'abstract_unit'
+# frozen_string_literal: true
+
+require "abstract_unit"
 
 module ActionDispatch
   module Routing
@@ -9,7 +11,7 @@ module ActionDispatch
         end
 
         def call(env)
-          [ 200, { 'Content-Type' => 'text/plain' }, [response] ]
+          [ 200, { "Content-Type" => "text/plain" }, [response] ]
         end
       end
 
@@ -21,7 +23,7 @@ module ActionDispatch
         assert empty?
 
         draw do
-          get 'foo', to: SimpleApp.new('foo#index')
+          get "foo", to: SimpleApp.new("foo#index")
         end
 
         assert_not empty?
@@ -29,101 +31,101 @@ module ActionDispatch
 
       test "url helpers are added when route is added" do
         draw do
-          get 'foo', to: SimpleApp.new('foo#index')
+          get "foo", to: SimpleApp.new("foo#index")
         end
 
-        assert_equal '/foo', url_helpers.foo_path
+        assert_equal "/foo", url_helpers.foo_path
         assert_raises NoMethodError do
-          assert_equal '/bar', url_helpers.bar_path
+          assert_equal "/bar", url_helpers.bar_path
         end
 
         draw do
-          get 'foo', to: SimpleApp.new('foo#index')
-          get 'bar', to: SimpleApp.new('bar#index')
+          get "foo", to: SimpleApp.new("foo#index")
+          get "bar", to: SimpleApp.new("bar#index")
         end
 
-        assert_equal '/foo', url_helpers.foo_path
-        assert_equal '/bar', url_helpers.bar_path
+        assert_equal "/foo", url_helpers.foo_path
+        assert_equal "/bar", url_helpers.bar_path
       end
 
       test "url helpers are updated when route is updated" do
         draw do
-          get 'bar', to: SimpleApp.new('bar#index'), as: :bar
+          get "bar", to: SimpleApp.new("bar#index"), as: :bar
         end
 
-        assert_equal '/bar', url_helpers.bar_path
+        assert_equal "/bar", url_helpers.bar_path
 
         draw do
-          get 'baz', to: SimpleApp.new('baz#index'), as: :bar
+          get "baz", to: SimpleApp.new("baz#index"), as: :bar
         end
 
-        assert_equal '/baz', url_helpers.bar_path
+        assert_equal "/baz", url_helpers.bar_path
       end
 
       test "url helpers are removed when route is removed" do
         draw do
-          get 'foo', to: SimpleApp.new('foo#index')
-          get 'bar', to: SimpleApp.new('bar#index')
+          get "foo", to: SimpleApp.new("foo#index")
+          get "bar", to: SimpleApp.new("bar#index")
         end
 
-        assert_equal '/foo', url_helpers.foo_path
-        assert_equal '/bar', url_helpers.bar_path
+        assert_equal "/foo", url_helpers.foo_path
+        assert_equal "/bar", url_helpers.bar_path
 
         draw do
-          get 'foo', to: SimpleApp.new('foo#index')
+          get "foo", to: SimpleApp.new("foo#index")
         end
 
-        assert_equal '/foo', url_helpers.foo_path
+        assert_equal "/foo", url_helpers.foo_path
         assert_raises NoMethodError do
-          assert_equal '/bar', url_helpers.bar_path
+          assert_equal "/bar", url_helpers.bar_path
         end
       end
 
       test "only_path: true with *_url and no :host option" do
         draw do
-          get 'foo', to: SimpleApp.new('foo#index')
+          get "foo", to: SimpleApp.new("foo#index")
         end
 
-        assert_equal '/foo', url_helpers.foo_url(only_path: true)
+        assert_equal "/foo", url_helpers.foo_url(only_path: true)
       end
 
       test "only_path: false with *_url and no :host option" do
         draw do
-          get 'foo', to: SimpleApp.new('foo#index')
+          get "foo", to: SimpleApp.new("foo#index")
         end
 
         assert_raises ArgumentError do
-          assert_equal 'http://example.com/foo', url_helpers.foo_url(only_path: false)
+          assert_equal "http://example.com/foo", url_helpers.foo_url(only_path: false)
         end
       end
 
       test "only_path: false with *_url and local :host option" do
         draw do
-          get 'foo', to: SimpleApp.new('foo#index')
+          get "foo", to: SimpleApp.new("foo#index")
         end
 
-        assert_equal 'http://example.com/foo', url_helpers.foo_url(only_path: false, host: 'example.com')
+        assert_equal "http://example.com/foo", url_helpers.foo_url(only_path: false, host: "example.com")
       end
 
       test "only_path: false with *_url and global :host option" do
-        @set.default_url_options = { host: 'example.com' }
+        @set.default_url_options = { host: "example.com" }
 
         draw do
-          get 'foo', to: SimpleApp.new('foo#index')
+          get "foo", to: SimpleApp.new("foo#index")
         end
 
-        assert_equal 'http://example.com/foo', url_helpers.foo_url(only_path: false)
+        assert_equal "http://example.com/foo", url_helpers.foo_url(only_path: false)
       end
 
       test "explicit keys win over implicit keys" do
         draw do
           resources :foo do
-            resources :bar, to: SimpleApp.new('foo#show')
+            resources :bar, to: SimpleApp.new("foo#show")
           end
         end
 
-        assert_equal '/foo/1/bar/2', url_helpers.foo_bar_path(1, 2)
-        assert_equal '/foo/1/bar/2', url_helpers.foo_bar_path(2, foo_id: 1)
+        assert_equal "/foo/1/bar/2", url_helpers.foo_bar_path(1, 2)
+        assert_equal "/foo/1/bar/2", url_helpers.foo_bar_path(2, foo_id: 1)
       end
 
       test "having an optional scope with resources" do
@@ -133,9 +135,18 @@ module ActionDispatch
           end
         end
 
-        assert_equal '/users/1', url_helpers.user_path(1)
-        assert_equal '/users/1', url_helpers.user_path(1, foo: nil)
-        assert_equal '/a/users/1', url_helpers.user_path(1, foo: 'a')
+        assert_equal "/users/1", url_helpers.user_path(1)
+        assert_equal "/users/1", url_helpers.user_path(1, foo: nil)
+        assert_equal "/a/users/1", url_helpers.user_path(1, foo: "a")
+      end
+
+      test "implicit path components consistently return the same result" do
+        draw do
+          resources :users, to: SimpleApp.new("foo#index")
+        end
+        assert_equal "/users/1.json", url_helpers.user_path(1, :json)
+        assert_equal "/users/1.json", url_helpers.user_path(1, format: :json)
+        assert_equal "/users/1.json", url_helpers.user_path(1, :json)
       end
 
       private
diff --git a/actionpack/test/dispatch/routing_assertions_test.rb b/actionpack/test/dispatch/routing_assertions_test.rb
index 56ea644f22..a5198f2f13 100644
--- a/actionpack/test/dispatch/routing_assertions_test.rb
+++ b/actionpack/test/dispatch/routing_assertions_test.rb
@@ -1,130 +1,202 @@
-require 'abstract_unit'
-require 'controller/fake_controllers'
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "rails/engine"
+require "controller/fake_controllers"
 
 class SecureArticlesController < ArticlesController; end
 class BlockArticlesController < ArticlesController; end
 class QueryArticlesController < ArticlesController; end
 
-class RoutingAssertionsTest < ActionController::TestCase
+class SecureBooksController < BooksController; end
+class BlockBooksController < BooksController; end
+class QueryBooksController < BooksController; end
 
+class RoutingAssertionsTest < ActionController::TestCase
   def setup
+    engine = Class.new(Rails::Engine) do
+      def self.name
+        "blog_engine"
+      end
+    end
+    engine.routes.draw do
+      resources :books
+
+      scope "secure", constraints: { protocol: "https://" } do
+        resources :books, controller: "secure_books"
+      end
+
+      scope "block", constraints: lambda { |r| r.ssl? } do
+        resources :books, controller: "block_books"
+      end
+
+      scope "query", constraints: lambda { |r| r.params[:use_query] == "true" } do
+        resources :books, controller: "query_books"
+      end
+    end
+
     @routes = ActionDispatch::Routing::RouteSet.new
     @routes.draw do
       resources :articles
 
-      scope 'secure', :constraints => { :protocol => 'https://' } do
-        resources :articles, :controller => 'secure_articles'
+      scope "secure", constraints: { protocol: "https://" } do
+        resources :articles, controller: "secure_articles"
       end
 
-      scope 'block', :constraints => lambda { |r| r.ssl? } do
-        resources :articles, :controller => 'block_articles'
+      scope "block", constraints: lambda { |r| r.ssl? } do
+        resources :articles, controller: "block_articles"
       end
 
-      scope 'query', :constraints => lambda { |r| r.params[:use_query] == 'true' } do
-        resources :articles, :controller => 'query_articles'
+      scope "query", constraints: lambda { |r| r.params[:use_query] == "true" } do
+        resources :articles, controller: "query_articles"
       end
+
+      mount engine => "/shelf"
     end
   end
 
   def test_assert_generates
-    assert_generates('/articles', { :controller => 'articles', :action => 'index' })
-    assert_generates('/articles/1', { :controller => 'articles', :action => 'show', :id => '1' })
+    assert_generates("/articles", controller: "articles", action: "index")
+    assert_generates("/articles/1", controller: "articles", action: "show", id: "1")
   end
 
   def test_assert_generates_with_defaults
-    assert_generates('/articles/1/edit', { :controller => 'articles', :action => 'edit' }, { :id => '1' })
+    assert_generates("/articles/1/edit", { controller: "articles", action: "edit" }, { id: "1" })
   end
 
   def test_assert_generates_with_extras
-    assert_generates('/articles', { :controller => 'articles', :action => 'index', :page => '1' }, {}, { :page => '1' })
+    assert_generates("/articles", { controller: "articles", action: "index", page: "1" }, {}, { page: "1" })
   end
 
   def test_assert_recognizes
-    assert_recognizes({ :controller => 'articles', :action => 'index' }, '/articles')
-    assert_recognizes({ :controller => 'articles', :action => 'show', :id => '1' }, '/articles/1')
+    assert_recognizes({ controller: "articles", action: "index" }, "/articles")
+    assert_recognizes({ controller: "articles", action: "show", id: "1" }, "/articles/1")
   end
 
   def test_assert_recognizes_with_extras
-    assert_recognizes({ :controller => 'articles', :action => 'index', :page => '1' }, '/articles', { :page => '1' })
+    assert_recognizes({ controller: "articles", action: "index", page: "1" }, "/articles", page: "1")
   end
 
   def test_assert_recognizes_with_method
-    assert_recognizes({ :controller => 'articles', :action => 'create' }, { :path => '/articles', :method => :post })
-    assert_recognizes({ :controller => 'articles', :action => 'update', :id => '1' }, { :path => '/articles/1', :method => :put })
+    assert_recognizes({ controller: "articles", action: "create" }, { path: "/articles", method: :post })
+    assert_recognizes({ controller: "articles", action: "update", id: "1" }, { path: "/articles/1", method: :put })
   end
 
   def test_assert_recognizes_with_hash_constraint
     assert_raise(Assertion) do
-      assert_recognizes({ :controller => 'secure_articles', :action => 'index' }, 'http://test.host/secure/articles')
+      assert_recognizes({ controller: "secure_articles", action: "index" }, "http://test.host/secure/articles")
     end
-    assert_recognizes({ :controller => 'secure_articles', :action => 'index', :protocol => 'https://' }, 'https://test.host/secure/articles')
+    assert_recognizes({ controller: "secure_articles", action: "index", protocol: "https://" }, "https://test.host/secure/articles")
   end
 
   def test_assert_recognizes_with_block_constraint
     assert_raise(Assertion) do
-      assert_recognizes({ :controller => 'block_articles', :action => 'index' }, 'http://test.host/block/articles')
+      assert_recognizes({ controller: "block_articles", action: "index" }, "http://test.host/block/articles")
     end
-    assert_recognizes({ :controller => 'block_articles', :action => 'index' }, 'https://test.host/block/articles')
+    assert_recognizes({ controller: "block_articles", action: "index" }, "https://test.host/block/articles")
   end
 
   def test_assert_recognizes_with_query_constraint
     assert_raise(Assertion) do
-      assert_recognizes({ :controller => 'query_articles', :action => 'index', :use_query => 'false' }, '/query/articles', { :use_query => 'false' })
+      assert_recognizes({ controller: "query_articles", action: "index", use_query: "false" }, "/query/articles", use_query: "false")
     end
-    assert_recognizes({ :controller => 'query_articles', :action => 'index', :use_query => 'true' }, '/query/articles', { :use_query => 'true' })
+    assert_recognizes({ controller: "query_articles", action: "index", use_query: "true" }, "/query/articles", use_query: "true")
   end
 
   def test_assert_recognizes_raises_message
     err = assert_raise(Assertion) do
-      assert_recognizes({ :controller => 'secure_articles', :action => 'index' }, 'http://test.host/secure/articles', {}, "This is a really bad msg")
+      assert_recognizes({ controller: "secure_articles", action: "index" }, "http://test.host/secure/articles", {}, "This is a really bad msg")
+    end
+
+    assert_match err.message, "This is a really bad msg"
+  end
+
+  def test_assert_recognizes_with_engine
+    assert_recognizes({ controller: "books", action: "index" }, "/shelf/books")
+    assert_recognizes({ controller: "books", action: "show", id: "1" }, "/shelf/books/1")
+  end
+
+  def test_assert_recognizes_with_engine_and_extras
+    assert_recognizes({ controller: "books", action: "index", page: "1" }, "/shelf/books", page: "1")
+  end
+
+  def test_assert_recognizes_with_engine_and_method
+    assert_recognizes({ controller: "books", action: "create" }, { path: "/shelf/books", method: :post })
+    assert_recognizes({ controller: "books", action: "update", id: "1" }, { path: "/shelf/books/1", method: :put })
+  end
+
+  def test_assert_recognizes_with_engine_and_hash_constraint
+    assert_raise(Assertion) do
+      assert_recognizes({ controller: "secure_books", action: "index" }, "http://test.host/shelf/secure/books")
+    end
+    assert_recognizes({ controller: "secure_books", action: "index", protocol: "https://" }, "https://test.host/shelf/secure/books")
+  end
+
+  def test_assert_recognizes_with_engine_and_block_constraint
+    assert_raise(Assertion) do
+      assert_recognizes({ controller: "block_books", action: "index" }, "http://test.host/shelf/block/books")
+    end
+    assert_recognizes({ controller: "block_books", action: "index" }, "https://test.host/shelf/block/books")
+  end
+
+  def test_assert_recognizes_with_engine_and_query_constraint
+    assert_raise(Assertion) do
+      assert_recognizes({ controller: "query_books", action: "index", use_query: "false" }, "/shelf/query/books", use_query: "false")
+    end
+    assert_recognizes({ controller: "query_books", action: "index", use_query: "true" }, "/shelf/query/books", use_query: "true")
+  end
+
+  def test_assert_recognizes_raises_message_with_engine
+    err = assert_raise(Assertion) do
+      assert_recognizes({ controller: "secure_books", action: "index" }, "http://test.host/shelf/secure/books", {}, "This is a really bad msg")
     end
 
     assert_match err.message, "This is a really bad msg"
   end
 
   def test_assert_routing
-    assert_routing('/articles', :controller => 'articles', :action => 'index')
+    assert_routing("/articles", controller: "articles", action: "index")
   end
 
   def test_assert_routing_raises_message
     err = assert_raise(Assertion) do
-      assert_routing('/thisIsNotARoute', { :controller => 'articles', :action => 'edit', :id => '1' }, { :id => '1' }, {}, "This is a really bad msg")
+      assert_routing("/thisIsNotARoute", { controller: "articles", action: "edit", id: "1" }, { id: "1" }, {}, "This is a really bad msg")
     end
 
     assert_match err.message, "This is a really bad msg"
   end
 
   def test_assert_routing_with_defaults
-    assert_routing('/articles/1/edit', { :controller => 'articles', :action => 'edit', :id => '1' }, { :id => '1' })
+    assert_routing("/articles/1/edit", { controller: "articles", action: "edit", id: "1" }, { id: "1" })
   end
 
   def test_assert_routing_with_extras
-    assert_routing('/articles', { :controller => 'articles', :action => 'index', :page => '1' }, { }, { :page => '1' })
+    assert_routing("/articles", { controller: "articles", action: "index", page: "1" }, {}, { page: "1" })
   end
 
   def test_assert_routing_with_hash_constraint
     assert_raise(Assertion) do
-      assert_routing('http://test.host/secure/articles', { :controller => 'secure_articles', :action => 'index' })
+      assert_routing("http://test.host/secure/articles", controller: "secure_articles", action: "index")
     end
-    assert_routing('https://test.host/secure/articles', { :controller => 'secure_articles', :action => 'index', :protocol => 'https://' })
+    assert_routing("https://test.host/secure/articles", controller: "secure_articles", action: "index", protocol: "https://")
   end
 
   def test_assert_routing_with_block_constraint
     assert_raise(Assertion) do
-      assert_routing('http://test.host/block/articles', { :controller => 'block_articles', :action => 'index' })
+      assert_routing("http://test.host/block/articles", controller: "block_articles", action: "index")
     end
-    assert_routing('https://test.host/block/articles', { :controller => 'block_articles', :action => 'index' })
+    assert_routing("https://test.host/block/articles", controller: "block_articles", action: "index")
   end
 
   def test_with_routing
     with_routing do |routes|
       routes.draw do
-        resources :articles, :path => 'artikel'
+        resources :articles, path: "artikel"
       end
 
-      assert_routing('/artikel', :controller => 'articles', :action => 'index')
+      assert_routing("/artikel", controller: "articles", action: "index")
       assert_raise(Assertion) do
-        assert_routing('/articles', { :controller => 'articles', :action => 'index' })
+        assert_routing("/articles", controller: "articles", action: "index")
       end
     end
   end
diff --git a/actionpack/test/dispatch/routing_test.rb b/actionpack/test/dispatch/routing_test.rb
index 75fdc9469f..8f4e7c96a9 100644
--- a/actionpack/test/dispatch/routing_test.rb
+++ b/actionpack/test/dispatch/routing_test.rb
@@ -1,10 +1,13 @@
-require 'erb'
-require 'abstract_unit'
-require 'controller/fake_controllers'
+# frozen_string_literal: true
+
+require "erb"
+require "abstract_unit"
+require "controller/fake_controllers"
+require "active_support/messages/rotation_configuration"
 
 class TestRoutingMapper < ActionDispatch::IntegrationTest
   SprocketsApp = lambda { |env|
-    [200, {"Content-Type" => "text/html"}, ["javascripts"]]
+    [200, { "Content-Type" => "text/html" }, ["javascripts"]]
   }
 
   class IpRestrictor
@@ -28,87 +31,87 @@ class TestRoutingMapper < ActionDispatch::IntegrationTest
   def test_logout
     draw do
       controller :sessions do
-        delete 'logout' => :destroy
+        delete "logout" => :destroy
       end
     end
 
-    delete '/logout'
-    assert_equal 'sessions#destroy', @response.body
+    delete "/logout"
+    assert_equal "sessions#destroy", @response.body
 
-    assert_equal '/logout', logout_path
-    assert_equal '/logout', url_for(:controller => 'sessions', :action => 'destroy', :only_path => true)
+    assert_equal "/logout", logout_path
+    assert_equal "/logout", url_for(controller: "sessions", action: "destroy", only_path: true)
   end
 
   def test_login
     draw do
-      default_url_options :host => "rubyonrails.org"
+      default_url_options host: "rubyonrails.org"
 
       controller :sessions do
-        get  'login' => :new
-        post 'login' => :create
+        get  "login" => :new
+        post "login" => :create
       end
     end
 
-    get '/login'
-    assert_equal 'sessions#new', @response.body
-    assert_equal '/login', login_path
+    get "/login"
+    assert_equal "sessions#new", @response.body
+    assert_equal "/login", login_path
 
-    post '/login'
-    assert_equal 'sessions#create', @response.body
+    post "/login"
+    assert_equal "sessions#create", @response.body
 
-    assert_equal '/login', url_for(:controller => 'sessions', :action => 'create', :only_path => true)
-    assert_equal '/login', url_for(:controller => 'sessions', :action => 'new', :only_path => true)
+    assert_equal "/login", url_for(controller: "sessions", action: "create", only_path: true)
+    assert_equal "/login", url_for(controller: "sessions", action: "new", only_path: true)
 
-    assert_equal 'http://rubyonrails.org/login', url_for(:controller => 'sessions', :action => 'create')
-    assert_equal 'http://rubyonrails.org/login', login_url
+    assert_equal "http://rubyonrails.org/login", url_for(controller: "sessions", action: "create")
+    assert_equal "http://rubyonrails.org/login", login_url
   end
 
   def test_login_redirect
     draw do
-      get 'account/login', :to => redirect("/login")
+      get "account/login", to: redirect("/login")
     end
 
-    get '/account/login'
-    verify_redirect 'http://www.example.com/login'
+    get "/account/login"
+    verify_redirect "http://www.example.com/login"
   end
 
   def test_logout_redirect_without_to
     draw do
-      get 'account/logout' => redirect("/logout"), :as => :logout_redirect
+      get "account/logout" => redirect("/logout"), :as => :logout_redirect
     end
 
-    assert_equal '/account/logout', logout_redirect_path
-    get '/account/logout'
-    verify_redirect 'http://www.example.com/logout'
+    assert_equal "/account/logout", logout_redirect_path
+    get "/account/logout"
+    verify_redirect "http://www.example.com/logout"
   end
 
   def test_namespace_redirect
     draw do
       namespace :private do
-        root :to => redirect('/private/index')
-        get "index", :to => 'private#index'
+        root to: redirect("/private/index")
+        get "index", to: "private#index"
       end
     end
 
-    get '/private'
-    verify_redirect 'http://www.example.com/private/index'
+    get "/private"
+    verify_redirect "http://www.example.com/private/index"
   end
 
   def test_redirect_with_failing_constraint
     draw do
-      get 'hi', to: redirect("/foo"), constraints: ::TestRoutingMapper::GrumpyRestrictor
+      get "hi", to: redirect("/foo"), constraints: ::TestRoutingMapper::GrumpyRestrictor
     end
 
-    get '/hi'
+    get "/hi"
     assert_equal 404, status
   end
 
   def test_redirect_with_passing_constraint
     draw do
-      get 'hi', to: redirect("/foo"), constraints: ->(req) { true }
+      get "hi", to: redirect("/foo"), constraints: ->(req) { true }
     end
 
-    get '/hi'
+    get "/hi"
     assert_equal 301, status
   end
 
@@ -117,7 +120,7 @@ class TestRoutingMapper < ActionDispatch::IntegrationTest
       draw do
         namespace :admin do
           ActiveSupport::Deprecation.silence do
-            get '/:controller(/:action(/:id(.:format)))'
+            get "/:controller(/:action(/:id(.:format)))"
           end
         end
       end
@@ -128,12 +131,12 @@ class TestRoutingMapper < ActionDispatch::IntegrationTest
     draw do
       namespace :admin do
         ActiveSupport::Deprecation.silence do
-          get 'hello/:controllers/:action'
+          get "hello/:controllers/:action"
         end
       end
     end
-    get '/admin/hello/foo/new'
-    assert_equal 'foo', @request.params["controllers"]
+    get "/admin/hello/foo/new"
+    assert_equal "foo", @request.params["controllers"]
   end
 
   def test_session_singleton_resource
@@ -144,30 +147,30 @@ class TestRoutingMapper < ActionDispatch::IntegrationTest
       end
     end
 
-    get '/session'
-    assert_equal 'sessions#create', @response.body
-    assert_equal '/session', session_path
+    get "/session"
+    assert_equal "sessions#create", @response.body
+    assert_equal "/session", session_path
 
-    post '/session'
-    assert_equal 'sessions#create', @response.body
+    post "/session"
+    assert_equal "sessions#create", @response.body
 
-    put '/session'
-    assert_equal 'sessions#update', @response.body
+    put "/session"
+    assert_equal "sessions#update", @response.body
 
-    delete '/session'
-    assert_equal 'sessions#destroy', @response.body
+    delete "/session"
+    assert_equal "sessions#destroy", @response.body
 
-    get '/session/new'
-    assert_equal 'sessions#new', @response.body
-    assert_equal '/session/new', new_session_path
+    get "/session/new"
+    assert_equal "sessions#new", @response.body
+    assert_equal "/session/new", new_session_path
 
-    get '/session/edit'
-    assert_equal 'sessions#edit', @response.body
-    assert_equal '/session/edit', edit_session_path
+    get "/session/edit"
+    assert_equal "sessions#edit", @response.body
+    assert_equal "/session/edit", edit_session_path
 
-    post '/session/reset'
-    assert_equal 'sessions#reset', @response.body
-    assert_equal '/session/reset', reset_session_path
+    post "/session/reset"
+    assert_equal "sessions#reset", @response.body
+    assert_equal "/session/reset", reset_session_path
   end
 
   def test_session_singleton_resource_for_api_app
@@ -184,28 +187,28 @@ class TestRoutingMapper < ActionDispatch::IntegrationTest
       @app = RoutedRackApp.new routes
     end
 
-    get '/session'
-    assert_equal 'sessions#create', @response.body
-    assert_equal '/session', session_path
+    get "/session"
+    assert_equal "sessions#create", @response.body
+    assert_equal "/session", session_path
 
-    post '/session'
-    assert_equal 'sessions#create', @response.body
+    post "/session"
+    assert_equal "sessions#create", @response.body
 
-    put '/session'
-    assert_equal 'sessions#update', @response.body
+    put "/session"
+    assert_equal "sessions#update", @response.body
 
-    delete '/session'
-    assert_equal 'sessions#destroy', @response.body
+    delete "/session"
+    assert_equal "sessions#destroy", @response.body
 
-    post '/session/reset'
-    assert_equal 'sessions#reset', @response.body
-    assert_equal '/session/reset', reset_session_path
+    post "/session/reset"
+    assert_equal "sessions#reset", @response.body
+    assert_equal "/session/reset", reset_session_path
 
-    get '/session/new'
-    assert_equal 'Not Found', @response.body
+    get "/session/new"
+    assert_equal "Not Found", @response.body
 
-    get '/session/edit'
-    assert_equal 'Not Found', @response.body
+    get "/session/edit"
+    assert_equal "Not Found", @response.body
   end
 
   def test_session_info_nested_singleton_resource
@@ -215,9 +218,9 @@ class TestRoutingMapper < ActionDispatch::IntegrationTest
       end
     end
 
-    get '/session/info'
-    assert_equal 'infos#show', @response.body
-    assert_equal '/session/info', session_info_path
+    get "/session/info"
+    assert_equal "infos#show", @response.body
+    assert_equal "/session/info", session_info_path
   end
 
   def test_member_on_resource
@@ -229,241 +232,243 @@ class TestRoutingMapper < ActionDispatch::IntegrationTest
       end
     end
 
-    get '/session/crush'
-    assert_equal 'sessions#crush', @response.body
-    assert_equal '/session/crush', crush_session_path
+    get "/session/crush"
+    assert_equal "sessions#crush", @response.body
+    assert_equal "/session/crush", crush_session_path
   end
 
   def test_redirect_modulo
     draw do
-      get 'account/modulo/:name', :to => redirect("/%{name}s")
+      get "account/modulo/:name", to: redirect("/%{name}s")
     end
 
-    get '/account/modulo/name'
-    verify_redirect 'http://www.example.com/names'
+    get "/account/modulo/name"
+    verify_redirect "http://www.example.com/names"
   end
 
   def test_redirect_proc
     draw do
-      get 'account/proc/:name', :to => redirect {|params, req| "/#{params[:name].pluralize}" }
+      get "account/proc/:name", to: redirect { |params, req| "/#{params[:name].pluralize}" }
     end
 
-    get '/account/proc/person'
-    verify_redirect 'http://www.example.com/people'
+    get "/account/proc/person"
+    verify_redirect "http://www.example.com/people"
   end
 
   def test_redirect_proc_with_request
     draw do
-      get 'account/proc_req' => redirect {|params, req| "/#{req.method}" }
+      get "account/proc_req" => redirect { |params, req| "/#{req.method}" }
     end
 
-    get '/account/proc_req'
-    verify_redirect 'http://www.example.com/GET'
+    get "/account/proc_req"
+    verify_redirect "http://www.example.com/GET"
   end
 
   def test_redirect_hash_with_subdomain
     draw do
-      get 'mobile', :to => redirect(:subdomain => 'mobile')
+      get "mobile", to: redirect(subdomain: "mobile")
     end
 
-    get '/mobile'
-    verify_redirect 'http://mobile.example.com/mobile'
+    get "/mobile"
+    verify_redirect "http://mobile.example.com/mobile"
   end
 
   def test_redirect_hash_with_domain_and_path
     draw do
-      get 'documentation', :to => redirect(:domain => 'example-documentation.com', :path => '')
+      get "documentation", to: redirect(domain: "example-documentation.com", path: "")
     end
 
-    get '/documentation'
-    verify_redirect 'http://www.example-documentation.com'
+    get "/documentation"
+    verify_redirect "http://www.example-documentation.com"
   end
 
   def test_redirect_hash_with_path
     draw do
-      get 'new_documentation', :to => redirect(:path => '/documentation/new')
+      get "new_documentation", to: redirect(path: "/documentation/new")
     end
 
-    get '/new_documentation'
-    verify_redirect 'http://www.example.com/documentation/new'
+    get "/new_documentation"
+    verify_redirect "http://www.example.com/documentation/new"
   end
 
   def test_redirect_hash_with_host
     draw do
-      get 'super_new_documentation', :to => redirect(:host => 'super-docs.com')
+      get "super_new_documentation", to: redirect(host: "super-docs.com")
     end
 
-    get '/super_new_documentation?section=top'
-    verify_redirect 'http://super-docs.com/super_new_documentation?section=top'
+    get "/super_new_documentation?section=top"
+    verify_redirect "http://super-docs.com/super_new_documentation?section=top"
   end
 
   def test_redirect_hash_path_substitution
     draw do
-      get 'stores/:name', :to => redirect(:subdomain => 'stores', :path => '/%{name}')
+      get "stores/:name", to: redirect(subdomain: "stores", path: "/%{name}")
     end
 
-    get '/stores/iernest'
-    verify_redirect 'http://stores.example.com/iernest'
+    get "/stores/iernest"
+    verify_redirect "http://stores.example.com/iernest"
   end
 
   def test_redirect_hash_path_substitution_with_catch_all
     draw do
-      get 'stores/:name(*rest)', :to => redirect(:subdomain => 'stores', :path => '/%{name}%{rest}')
+      get "stores/:name(*rest)", to: redirect(subdomain: "stores", path: "/%{name}%{rest}")
     end
 
-    get '/stores/iernest/products'
-    verify_redirect 'http://stores.example.com/iernest/products'
+    get "/stores/iernest/products"
+    verify_redirect "http://stores.example.com/iernest/products"
   end
 
   def test_redirect_class
     draw do
-      get 'youtube_favorites/:youtube_id/:name', :to => redirect(YoutubeFavoritesRedirector)
+      get "youtube_favorites/:youtube_id/:name", to: redirect(YoutubeFavoritesRedirector)
     end
 
-    get '/youtube_favorites/oHg5SJYRHA0/rick-rolld'
-    verify_redirect 'http://www.youtube.com/watch?v=oHg5SJYRHA0'
+    get "/youtube_favorites/oHg5SJYRHA0/rick-rolld"
+    verify_redirect "http://www.youtube.com/watch?v=oHg5SJYRHA0"
   end
 
   def test_openid
     draw do
-      match 'openid/login', :via => [:get, :post], :to => "openid#login"
+      match "openid/login", via: [:get, :post], to: "openid#login"
     end
 
-    get '/openid/login'
-    assert_equal 'openid#login', @response.body
+    get "/openid/login"
+    assert_equal "openid#login", @response.body
 
-    post '/openid/login'
-    assert_equal 'openid#login', @response.body
+    post "/openid/login"
+    assert_equal "openid#login", @response.body
   end
 
   def test_bookmarks
     draw do
-      scope "bookmark", :controller => "bookmarks", :as => :bookmark do
-        get  :new, :path => "build"
-        post :create, :path => "create", :as => ""
+      scope "bookmark", controller: "bookmarks", as: :bookmark do
+        get  :new, path: "build"
+        post :create, path: "create", as: ""
         put  :update
-        get  :remove, :action => :destroy, :as => :remove
+        get  :remove, action: :destroy, as: :remove
       end
     end
 
-    get '/bookmark/build'
-    assert_equal 'bookmarks#new', @response.body
-    assert_equal '/bookmark/build', bookmark_new_path
+    get "/bookmark/build"
+    assert_equal "bookmarks#new", @response.body
+    assert_equal "/bookmark/build", bookmark_new_path
 
-    post '/bookmark/create'
-    assert_equal 'bookmarks#create', @response.body
-    assert_equal '/bookmark/create', bookmark_path
+    post "/bookmark/create"
+    assert_equal "bookmarks#create", @response.body
+    assert_equal "/bookmark/create", bookmark_path
 
-    put '/bookmark/update'
-    assert_equal 'bookmarks#update', @response.body
-    assert_equal '/bookmark/update', bookmark_update_path
+    put "/bookmark/update"
+    assert_equal "bookmarks#update", @response.body
+    assert_equal "/bookmark/update", bookmark_update_path
 
-    get '/bookmark/remove'
-    assert_equal 'bookmarks#destroy', @response.body
-    assert_equal '/bookmark/remove', bookmark_remove_path
+    get "/bookmark/remove"
+    assert_equal "bookmarks#destroy", @response.body
+    assert_equal "/bookmark/remove", bookmark_remove_path
   end
 
   def test_pagemarks
-    tc = self
     draw do
-      scope "pagemark", :controller => "pagemarks", :as => :pagemark do
-        tc.assert_deprecated do
-          get  "new", :path => "build"
-        end
-        post "create", :as => ""
+      scope "pagemark", controller: "pagemarks", as: :pagemark do
+        get "build", action: "new", as: "new"
+        post "create", as: ""
         put  "update"
-        get  "remove", :action => :destroy, :as => :remove
+        get  "remove", action: :destroy, as: :remove
+        get "", action: :show, as: :show
       end
     end
 
-    get '/pagemark/build'
-    assert_equal 'pagemarks#new', @response.body
-    assert_equal '/pagemark/build', pagemark_new_path
+    get "/pagemark/build"
+    assert_equal "pagemarks#new", @response.body
+    assert_equal "/pagemark/build", pagemark_new_path
 
-    post '/pagemark/create'
-    assert_equal 'pagemarks#create', @response.body
-    assert_equal '/pagemark/create', pagemark_path
+    post "/pagemark/create"
+    assert_equal "pagemarks#create", @response.body
+    assert_equal "/pagemark/create", pagemark_path
 
-    put '/pagemark/update'
-    assert_equal 'pagemarks#update', @response.body
-    assert_equal '/pagemark/update', pagemark_update_path
+    put "/pagemark/update"
+    assert_equal "pagemarks#update", @response.body
+    assert_equal "/pagemark/update", pagemark_update_path
 
-    get '/pagemark/remove'
-    assert_equal 'pagemarks#destroy', @response.body
-    assert_equal '/pagemark/remove', pagemark_remove_path
+    get "/pagemark/remove"
+    assert_equal "pagemarks#destroy", @response.body
+    assert_equal "/pagemark/remove", pagemark_remove_path
+
+    get "/pagemark"
+    assert_equal "pagemarks#show", @response.body
+    assert_equal "/pagemark", pagemark_show_path
   end
 
   def test_admin
     draw do
-      constraints(:ip => /192\.168\.1\.\d\d\d/) do
-        get 'admin' => "queenbee#index"
+      constraints(ip: /192\.168\.1\.\d\d\d/) do
+        get "admin" => "queenbee#index"
       end
 
       constraints ::TestRoutingMapper::IpRestrictor do
-        get 'admin/accounts' => "queenbee#accounts"
+        get "admin/accounts" => "queenbee#accounts"
       end
 
-      get 'admin/passwords' => "queenbee#passwords", :constraints => ::TestRoutingMapper::IpRestrictor
+      get "admin/passwords" => "queenbee#passwords", :constraints => ::TestRoutingMapper::IpRestrictor
     end
 
-    get '/admin', headers: { 'REMOTE_ADDR' => '192.168.1.100' }
-    assert_equal 'queenbee#index', @response.body
+    get "/admin", headers: { "REMOTE_ADDR" => "192.168.1.100" }
+    assert_equal "queenbee#index", @response.body
 
-    get '/admin', headers: { 'REMOTE_ADDR' => '10.0.0.100' }
-    assert_equal 'pass', @response.headers['X-Cascade']
+    get "/admin", headers: { "REMOTE_ADDR" => "10.0.0.100" }
+    assert_equal "pass", @response.headers["X-Cascade"]
 
-    get '/admin/accounts', headers: { 'REMOTE_ADDR' => '192.168.1.100' }
-    assert_equal 'queenbee#accounts', @response.body
+    get "/admin/accounts", headers: { "REMOTE_ADDR" => "192.168.1.100" }
+    assert_equal "queenbee#accounts", @response.body
 
-    get '/admin/accounts', headers: { 'REMOTE_ADDR' => '10.0.0.100' }
-    assert_equal 'pass', @response.headers['X-Cascade']
+    get "/admin/accounts", headers: { "REMOTE_ADDR" => "10.0.0.100" }
+    assert_equal "pass", @response.headers["X-Cascade"]
 
-    get '/admin/passwords', headers: { 'REMOTE_ADDR' => '192.168.1.100' }
-    assert_equal 'queenbee#passwords', @response.body
+    get "/admin/passwords", headers: { "REMOTE_ADDR" => "192.168.1.100" }
+    assert_equal "queenbee#passwords", @response.body
 
-    get '/admin/passwords', headers: { 'REMOTE_ADDR' => '10.0.0.100' }
-    assert_equal 'pass', @response.headers['X-Cascade']
+    get "/admin/passwords", headers: { "REMOTE_ADDR" => "10.0.0.100" }
+    assert_equal "pass", @response.headers["X-Cascade"]
   end
 
   def test_global
     draw do
       controller(:global) do
-        get 'global/hide_notice'
-        get 'global/export',      :action => :export, :as => :export_request
-        get '/export/:id/:file',  :action => :export, :as => :export_download, :constraints => { :file => /.*/ }
+        get "global/hide_notice"
+        get "global/export",      action: :export, as: :export_request
+        get "/export/:id/:file",  action: :export, as: :export_download, constraints: { file: /.*/ }
 
         ActiveSupport::Deprecation.silence do
-          get 'global/:action'
+          get "global/:action"
         end
       end
     end
 
-    get '/global/dashboard'
-    assert_equal 'global#dashboard', @response.body
+    get "/global/dashboard"
+    assert_equal "global#dashboard", @response.body
 
-    get '/global/export'
-    assert_equal 'global#export', @response.body
+    get "/global/export"
+    assert_equal "global#export", @response.body
 
-    get '/global/hide_notice'
-    assert_equal 'global#hide_notice', @response.body
+    get "/global/hide_notice"
+    assert_equal "global#hide_notice", @response.body
 
-    get '/export/123/foo.txt'
-    assert_equal 'global#export', @response.body
+    get "/export/123/foo.txt"
+    assert_equal "global#export", @response.body
 
-    assert_equal '/global/export', export_request_path
-    assert_equal '/global/hide_notice', global_hide_notice_path
-    assert_equal '/export/123/foo.txt', export_download_path(:id => 123, :file => 'foo.txt')
+    assert_equal "/global/export", export_request_path
+    assert_equal "/global/hide_notice", global_hide_notice_path
+    assert_equal "/export/123/foo.txt", export_download_path(id: 123, file: "foo.txt")
   end
 
   def test_local
     draw do
       ActiveSupport::Deprecation.silence do
-        get "/local/:action", :controller => "local"
+        get "/local/:action", controller: "local"
       end
     end
 
-    get '/local/dashboard'
-    assert_equal 'local#dashboard', @response.body
+    get "/local/dashboard"
+    assert_equal "local#dashboard", @response.body
   end
 
   # tests the use of dup in url_for
@@ -473,7 +478,7 @@ class TestRoutingMapper < ActionDispatch::IntegrationTest
     end
 
     # without dup, additional (and possibly unwanted) values will be present in the options (eg. :host)
-    original_options = {:controller => 'projects', :action => 'status'}
+    original_options = { controller: "projects", action: "status" }
     options = original_options.dup
 
     url_for options
@@ -487,23 +492,23 @@ class TestRoutingMapper < ActionDispatch::IntegrationTest
       get "/projects/status(.:format)"
     end
 
-    controller = '/projects'
-    options = {:controller => controller, :action => 'status', :only_path => true}
+    controller = "/projects"
+    options = { controller: controller, action: "status", only_path: true }
     url = url_for(options)
 
-    assert_equal '/projects/status', url
-    assert_equal '/projects', controller
+    assert_equal "/projects/status", url
+    assert_equal "/projects", controller
   end
 
   # tests the arguments modification free version of define_hash_access
   def test_named_route_with_no_side_effects
     draw do
       resources :customers do
-        get "profile", :on => :member
+        get "profile", on: :member
       end
     end
 
-    original_options = { :host => 'test.host' }
+    original_options = { host: "test.host" }
     options = original_options.dup
 
     profile_customer_url("customer_model", options)
@@ -517,45 +522,45 @@ class TestRoutingMapper < ActionDispatch::IntegrationTest
       get "/projects/status(.:format)"
     end
 
-    assert_equal '/projects/status', url_for(:controller => 'projects', :action => 'status', :only_path => true)
-    assert_equal '/projects/status.json', url_for(:controller => 'projects', :action => 'status', :format => 'json', :only_path => true)
+    assert_equal "/projects/status", url_for(controller: "projects", action: "status", only_path: true)
+    assert_equal "/projects/status.json", url_for(controller: "projects", action: "status", format: "json", only_path: true)
   end
 
   def test_projects
     draw do
-      resources :projects, :controller => :project
+      resources :projects, controller: :project
     end
 
-    get '/projects'
-    assert_equal 'project#index', @response.body
-    assert_equal '/projects', projects_path
+    get "/projects"
+    assert_equal "project#index", @response.body
+    assert_equal "/projects", projects_path
 
-    post '/projects'
-    assert_equal 'project#create', @response.body
+    post "/projects"
+    assert_equal "project#create", @response.body
 
-    get '/projects.xml'
-    assert_equal 'project#index', @response.body
-    assert_equal '/projects.xml', projects_path(:format => 'xml')
+    get "/projects.xml"
+    assert_equal "project#index", @response.body
+    assert_equal "/projects.xml", projects_path(format: "xml")
 
-    get '/projects/new'
-    assert_equal 'project#new', @response.body
-    assert_equal '/projects/new', new_project_path
+    get "/projects/new"
+    assert_equal "project#new", @response.body
+    assert_equal "/projects/new", new_project_path
 
-    get '/projects/new.xml'
-    assert_equal 'project#new', @response.body
-    assert_equal '/projects/new.xml', new_project_path(:format => 'xml')
+    get "/projects/new.xml"
+    assert_equal "project#new", @response.body
+    assert_equal "/projects/new.xml", new_project_path(format: "xml")
 
-    get '/projects/1'
-    assert_equal 'project#show', @response.body
-    assert_equal '/projects/1', project_path(:id => '1')
+    get "/projects/1"
+    assert_equal "project#show", @response.body
+    assert_equal "/projects/1", project_path(id: "1")
 
-    get '/projects/1.xml'
-    assert_equal 'project#show', @response.body
-    assert_equal '/projects/1.xml', project_path(:id => '1', :format => 'xml')
+    get "/projects/1.xml"
+    assert_equal "project#show", @response.body
+    assert_equal "/projects/1.xml", project_path(id: "1", format: "xml")
 
-    get '/projects/1/edit'
-    assert_equal 'project#edit', @response.body
-    assert_equal '/projects/1/edit', edit_project_path(:id => '1')
+    get "/projects/1/edit"
+    assert_equal "project#edit", @response.body
+    assert_equal "/projects/1/edit", edit_project_path(id: "1")
   end
 
   def test_projects_for_api_app
@@ -569,166 +574,166 @@ class TestRoutingMapper < ActionDispatch::IntegrationTest
       @app = RoutedRackApp.new routes
     end
 
-    get '/projects'
-    assert_equal 'project#index', @response.body
-    assert_equal '/projects', projects_path
+    get "/projects"
+    assert_equal "project#index", @response.body
+    assert_equal "/projects", projects_path
 
-    post '/projects'
-    assert_equal 'project#create', @response.body
+    post "/projects"
+    assert_equal "project#create", @response.body
 
-    get '/projects.xml'
-    assert_equal 'project#index', @response.body
-    assert_equal '/projects.xml', projects_path(format: 'xml')
+    get "/projects.xml"
+    assert_equal "project#index", @response.body
+    assert_equal "/projects.xml", projects_path(format: "xml")
 
-    get '/projects/1'
-    assert_equal 'project#show', @response.body
-    assert_equal '/projects/1', project_path(id: '1')
+    get "/projects/1"
+    assert_equal "project#show", @response.body
+    assert_equal "/projects/1", project_path(id: "1")
 
-    get '/projects/1.xml'
-    assert_equal 'project#show', @response.body
-    assert_equal '/projects/1.xml', project_path(id: '1', format: 'xml')
+    get "/projects/1.xml"
+    assert_equal "project#show", @response.body
+    assert_equal "/projects/1.xml", project_path(id: "1", format: "xml")
 
-    get '/projects/1/edit'
-    assert_equal 'Not Found', @response.body
+    get "/projects/1/edit"
+    assert_equal "Not Found", @response.body
   end
 
   def test_projects_with_post_action_and_new_path_on_collection
     draw do
-      resources :projects, :controller => :project do
-        post 'new', :action => 'new', :on => :collection, :as => :new
+      resources :projects, controller: :project do
+        post "new", action: "new", on: :collection, as: :new
       end
     end
 
-    post '/projects/new'
+    post "/projects/new"
     assert_equal "project#new", @response.body
     assert_equal "/projects/new", new_projects_path
   end
 
   def test_projects_involvements
     draw do
-      resources :projects, :controller => :project do
+      resources :projects, controller: :project do
         resources :involvements, :attachments
       end
     end
 
-    get '/projects/1/involvements'
-    assert_equal 'involvements#index', @response.body
-    assert_equal '/projects/1/involvements', project_involvements_path(:project_id => '1')
+    get "/projects/1/involvements"
+    assert_equal "involvements#index", @response.body
+    assert_equal "/projects/1/involvements", project_involvements_path(project_id: "1")
 
-    get '/projects/1/involvements/new'
-    assert_equal 'involvements#new', @response.body
-    assert_equal '/projects/1/involvements/new', new_project_involvement_path(:project_id => '1')
+    get "/projects/1/involvements/new"
+    assert_equal "involvements#new", @response.body
+    assert_equal "/projects/1/involvements/new", new_project_involvement_path(project_id: "1")
 
-    get '/projects/1/involvements/1'
-    assert_equal 'involvements#show', @response.body
-    assert_equal '/projects/1/involvements/1', project_involvement_path(:project_id => '1', :id => '1')
+    get "/projects/1/involvements/1"
+    assert_equal "involvements#show", @response.body
+    assert_equal "/projects/1/involvements/1", project_involvement_path(project_id: "1", id: "1")
 
-    put '/projects/1/involvements/1'
-    assert_equal 'involvements#update', @response.body
+    put "/projects/1/involvements/1"
+    assert_equal "involvements#update", @response.body
 
-    delete '/projects/1/involvements/1'
-    assert_equal 'involvements#destroy', @response.body
+    delete "/projects/1/involvements/1"
+    assert_equal "involvements#destroy", @response.body
 
-    get '/projects/1/involvements/1/edit'
-    assert_equal 'involvements#edit', @response.body
-    assert_equal '/projects/1/involvements/1/edit', edit_project_involvement_path(:project_id => '1', :id => '1')
+    get "/projects/1/involvements/1/edit"
+    assert_equal "involvements#edit", @response.body
+    assert_equal "/projects/1/involvements/1/edit", edit_project_involvement_path(project_id: "1", id: "1")
   end
 
   def test_projects_attachments
     draw do
-      resources :projects, :controller => :project do
+      resources :projects, controller: :project do
         resources :involvements, :attachments
       end
     end
 
-    get '/projects/1/attachments'
-    assert_equal 'attachments#index', @response.body
-    assert_equal '/projects/1/attachments', project_attachments_path(:project_id => '1')
+    get "/projects/1/attachments"
+    assert_equal "attachments#index", @response.body
+    assert_equal "/projects/1/attachments", project_attachments_path(project_id: "1")
   end
 
   def test_projects_participants
     draw do
-      resources :projects, :controller => :project do
+      resources :projects, controller: :project do
         resources :participants do
-          put :update_all, :on => :collection
+          put :update_all, on: :collection
         end
       end
     end
 
-    get '/projects/1/participants'
-    assert_equal 'participants#index', @response.body
-    assert_equal '/projects/1/participants', project_participants_path(:project_id => '1')
+    get "/projects/1/participants"
+    assert_equal "participants#index", @response.body
+    assert_equal "/projects/1/participants", project_participants_path(project_id: "1")
 
-    put '/projects/1/participants/update_all'
-    assert_equal 'participants#update_all', @response.body
-    assert_equal '/projects/1/participants/update_all', update_all_project_participants_path(:project_id => '1')
+    put "/projects/1/participants/update_all"
+    assert_equal "participants#update_all", @response.body
+    assert_equal "/projects/1/participants/update_all", update_all_project_participants_path(project_id: "1")
   end
 
   def test_projects_companies
     draw do
-      resources :projects, :controller => :project do
+      resources :projects, controller: :project do
         resources :companies do
           resources :people
-          resource  :avatar, :controller => :avatar
+          resource  :avatar, controller: :avatar
         end
       end
     end
 
-    get '/projects/1/companies'
-    assert_equal 'companies#index', @response.body
-    assert_equal '/projects/1/companies', project_companies_path(:project_id => '1')
+    get "/projects/1/companies"
+    assert_equal "companies#index", @response.body
+    assert_equal "/projects/1/companies", project_companies_path(project_id: "1")
 
-    get '/projects/1/companies/1/people'
-    assert_equal 'people#index', @response.body
-    assert_equal '/projects/1/companies/1/people', project_company_people_path(:project_id => '1', :company_id => '1')
+    get "/projects/1/companies/1/people"
+    assert_equal "people#index", @response.body
+    assert_equal "/projects/1/companies/1/people", project_company_people_path(project_id: "1", company_id: "1")
 
-    get '/projects/1/companies/1/avatar'
-    assert_equal 'avatar#show', @response.body
-    assert_equal '/projects/1/companies/1/avatar', project_company_avatar_path(:project_id => '1', :company_id => '1')
+    get "/projects/1/companies/1/avatar"
+    assert_equal "avatar#show", @response.body
+    assert_equal "/projects/1/companies/1/avatar", project_company_avatar_path(project_id: "1", company_id: "1")
   end
 
   def test_project_manager
     draw do
       resources :projects do
-        resource :manager, :as => :super_manager do
+        resource :manager, as: :super_manager do
           post :fire
         end
       end
     end
 
-    get '/projects/1/manager'
-    assert_equal 'managers#show', @response.body
-    assert_equal '/projects/1/manager', project_super_manager_path(:project_id => '1')
+    get "/projects/1/manager"
+    assert_equal "managers#show", @response.body
+    assert_equal "/projects/1/manager", project_super_manager_path(project_id: "1")
 
-    get '/projects/1/manager/new'
-    assert_equal 'managers#new', @response.body
-    assert_equal '/projects/1/manager/new', new_project_super_manager_path(:project_id => '1')
+    get "/projects/1/manager/new"
+    assert_equal "managers#new", @response.body
+    assert_equal "/projects/1/manager/new", new_project_super_manager_path(project_id: "1")
 
-    post '/projects/1/manager/fire'
-    assert_equal 'managers#fire', @response.body
-    assert_equal '/projects/1/manager/fire', fire_project_super_manager_path(:project_id => '1')
+    post "/projects/1/manager/fire"
+    assert_equal "managers#fire", @response.body
+    assert_equal "/projects/1/manager/fire", fire_project_super_manager_path(project_id: "1")
   end
 
   def test_project_images
     draw do
       resources :projects do
-        resources :images, :as => :funny_images do
-          post :revise, :on => :member
+        resources :images, as: :funny_images do
+          post :revise, on: :member
         end
       end
     end
 
-    get '/projects/1/images'
-    assert_equal 'images#index', @response.body
-    assert_equal '/projects/1/images', project_funny_images_path(:project_id => '1')
+    get "/projects/1/images"
+    assert_equal "images#index", @response.body
+    assert_equal "/projects/1/images", project_funny_images_path(project_id: "1")
 
-    get '/projects/1/images/new'
-    assert_equal 'images#new', @response.body
-    assert_equal '/projects/1/images/new', new_project_funny_image_path(:project_id => '1')
+    get "/projects/1/images/new"
+    assert_equal "images#new", @response.body
+    assert_equal "/projects/1/images/new", new_project_funny_image_path(project_id: "1")
 
-    post '/projects/1/images/1/revise'
-    assert_equal 'images#revise', @response.body
-    assert_equal '/projects/1/images/1/revise', revise_project_funny_image_path(:project_id => '1', :id => '1')
+    post "/projects/1/images/1/revise"
+    assert_equal "images#revise", @response.body
+    assert_equal "/projects/1/images/1/revise", revise_project_funny_image_path(project_id: "1", id: "1")
   end
 
   def test_projects_people
@@ -749,181 +754,181 @@ class TestRoutingMapper < ActionDispatch::IntegrationTest
       end
     end
 
-    get '/projects/1/people'
-    assert_equal 'people#index', @response.body
-    assert_equal '/projects/1/people', project_people_path(:project_id => '1')
+    get "/projects/1/people"
+    assert_equal "people#index", @response.body
+    assert_equal "/projects/1/people", project_people_path(project_id: "1")
 
-    get '/projects/1/people/1'
-    assert_equal 'people#show', @response.body
-    assert_equal '/projects/1/people/1', project_person_path(:project_id => '1', :id => '1')
+    get "/projects/1/people/1"
+    assert_equal "people#show", @response.body
+    assert_equal "/projects/1/people/1", project_person_path(project_id: "1", id: "1")
 
-    get '/projects/1/people/1/7a2dec8/avatar'
-    assert_equal 'avatars#show', @response.body
-    assert_equal '/projects/1/people/1/7a2dec8/avatar', project_person_avatar_path(:project_id => '1', :person_id => '1', :access_token => '7a2dec8')
+    get "/projects/1/people/1/7a2dec8/avatar"
+    assert_equal "avatars#show", @response.body
+    assert_equal "/projects/1/people/1/7a2dec8/avatar", project_person_avatar_path(project_id: "1", person_id: "1", access_token: "7a2dec8")
 
-    put '/projects/1/people/1/accessible_projects'
-    assert_equal 'people#accessible_projects', @response.body
-    assert_equal '/projects/1/people/1/accessible_projects', accessible_projects_project_person_path(:project_id => '1', :id => '1')
+    put "/projects/1/people/1/accessible_projects"
+    assert_equal "people#accessible_projects", @response.body
+    assert_equal "/projects/1/people/1/accessible_projects", accessible_projects_project_person_path(project_id: "1", id: "1")
 
-    post '/projects/1/people/1/resend'
-    assert_equal 'people#resend', @response.body
-    assert_equal '/projects/1/people/1/resend', resend_project_person_path(:project_id => '1', :id => '1')
+    post "/projects/1/people/1/resend"
+    assert_equal "people#resend", @response.body
+    assert_equal "/projects/1/people/1/resend", resend_project_person_path(project_id: "1", id: "1")
 
-    post '/projects/1/people/1/generate_new_password'
-    assert_equal 'people#generate_new_password', @response.body
-    assert_equal '/projects/1/people/1/generate_new_password', generate_new_password_project_person_path(:project_id => '1', :id => '1')
+    post "/projects/1/people/1/generate_new_password"
+    assert_equal "people#generate_new_password", @response.body
+    assert_equal "/projects/1/people/1/generate_new_password", generate_new_password_project_person_path(project_id: "1", id: "1")
   end
 
   def test_projects_with_resources_path_names
     draw do
-      resources_path_names :correlation_indexes => "info_about_correlation_indexes"
+      resources_path_names correlation_indexes: "info_about_correlation_indexes"
 
       resources :projects do
-        get :correlation_indexes, :on => :collection
+        get :correlation_indexes, on: :collection
       end
     end
 
-    get '/projects/info_about_correlation_indexes'
-    assert_equal 'projects#correlation_indexes', @response.body
-    assert_equal '/projects/info_about_correlation_indexes', correlation_indexes_projects_path
+    get "/projects/info_about_correlation_indexes"
+    assert_equal "projects#correlation_indexes", @response.body
+    assert_equal "/projects/info_about_correlation_indexes", correlation_indexes_projects_path
   end
 
   def test_projects_posts
     draw do
       resources :projects do
         resources :posts do
-          get  :archive, :toggle_view, :on => :collection
-          post :preview, :on => :member
+          get  :archive, :toggle_view, on: :collection
+          post :preview, on: :member
 
           resource :subscription
 
           resources :comments do
-            post :preview, :on => :collection
+            post :preview, on: :collection
           end
         end
       end
     end
 
-    get '/projects/1/posts'
-    assert_equal 'posts#index', @response.body
-    assert_equal '/projects/1/posts', project_posts_path(:project_id => '1')
+    get "/projects/1/posts"
+    assert_equal "posts#index", @response.body
+    assert_equal "/projects/1/posts", project_posts_path(project_id: "1")
 
-    get '/projects/1/posts/archive'
-    assert_equal 'posts#archive', @response.body
-    assert_equal '/projects/1/posts/archive', archive_project_posts_path(:project_id => '1')
+    get "/projects/1/posts/archive"
+    assert_equal "posts#archive", @response.body
+    assert_equal "/projects/1/posts/archive", archive_project_posts_path(project_id: "1")
 
-    get '/projects/1/posts/toggle_view'
-    assert_equal 'posts#toggle_view', @response.body
-    assert_equal '/projects/1/posts/toggle_view', toggle_view_project_posts_path(:project_id => '1')
+    get "/projects/1/posts/toggle_view"
+    assert_equal "posts#toggle_view", @response.body
+    assert_equal "/projects/1/posts/toggle_view", toggle_view_project_posts_path(project_id: "1")
 
-    post '/projects/1/posts/1/preview'
-    assert_equal 'posts#preview', @response.body
-    assert_equal '/projects/1/posts/1/preview', preview_project_post_path(:project_id => '1', :id => '1')
+    post "/projects/1/posts/1/preview"
+    assert_equal "posts#preview", @response.body
+    assert_equal "/projects/1/posts/1/preview", preview_project_post_path(project_id: "1", id: "1")
 
-    get '/projects/1/posts/1/subscription'
-    assert_equal 'subscriptions#show', @response.body
-    assert_equal '/projects/1/posts/1/subscription', project_post_subscription_path(:project_id => '1', :post_id => '1')
+    get "/projects/1/posts/1/subscription"
+    assert_equal "subscriptions#show", @response.body
+    assert_equal "/projects/1/posts/1/subscription", project_post_subscription_path(project_id: "1", post_id: "1")
 
-    get '/projects/1/posts/1/comments'
-    assert_equal 'comments#index', @response.body
-    assert_equal '/projects/1/posts/1/comments', project_post_comments_path(:project_id => '1', :post_id => '1')
+    get "/projects/1/posts/1/comments"
+    assert_equal "comments#index", @response.body
+    assert_equal "/projects/1/posts/1/comments", project_post_comments_path(project_id: "1", post_id: "1")
 
-    post '/projects/1/posts/1/comments/preview'
-    assert_equal 'comments#preview', @response.body
-    assert_equal '/projects/1/posts/1/comments/preview', preview_project_post_comments_path(:project_id => '1', :post_id => '1')
+    post "/projects/1/posts/1/comments/preview"
+    assert_equal "comments#preview", @response.body
+    assert_equal "/projects/1/posts/1/comments/preview", preview_project_post_comments_path(project_id: "1", post_id: "1")
   end
 
   def test_replies
     draw do
       resources :replies do
         member do
-          put :answer, :action => :mark_as_answer
-          delete :answer, :action => :unmark_as_answer
+          put :answer, action: :mark_as_answer
+          delete :answer, action: :unmark_as_answer
         end
       end
     end
 
-    put '/replies/1/answer'
-    assert_equal 'replies#mark_as_answer', @response.body
+    put "/replies/1/answer"
+    assert_equal "replies#mark_as_answer", @response.body
 
-    delete '/replies/1/answer'
-    assert_equal 'replies#unmark_as_answer', @response.body
+    delete "/replies/1/answer"
+    assert_equal "replies#unmark_as_answer", @response.body
   end
 
   def test_resource_routes_with_only_and_except
     draw do
-      resources :posts, :only => [:index, :show] do
-        resources :comments, :except => :destroy
+      resources :posts, only: [:index, :show] do
+        resources :comments, except: :destroy
       end
     end
 
-    get '/posts'
-    assert_equal 'posts#index', @response.body
-    assert_equal '/posts', posts_path
+    get "/posts"
+    assert_equal "posts#index", @response.body
+    assert_equal "/posts", posts_path
 
-    get '/posts/1'
-    assert_equal 'posts#show', @response.body
-    assert_equal '/posts/1', post_path(:id => 1)
+    get "/posts/1"
+    assert_equal "posts#show", @response.body
+    assert_equal "/posts/1", post_path(id: 1)
 
-    get '/posts/1/comments'
-    assert_equal 'comments#index', @response.body
-    assert_equal '/posts/1/comments', post_comments_path(:post_id => 1)
+    get "/posts/1/comments"
+    assert_equal "comments#index", @response.body
+    assert_equal "/posts/1/comments", post_comments_path(post_id: 1)
 
-    post '/posts'
-    assert_equal 'pass', @response.headers['X-Cascade']
-    put '/posts/1'
-    assert_equal 'pass', @response.headers['X-Cascade']
-    delete '/posts/1'
-    assert_equal 'pass', @response.headers['X-Cascade']
-    delete '/posts/1/comments'
-    assert_equal 'pass', @response.headers['X-Cascade']
+    post "/posts"
+    assert_equal "pass", @response.headers["X-Cascade"]
+    put "/posts/1"
+    assert_equal "pass", @response.headers["X-Cascade"]
+    delete "/posts/1"
+    assert_equal "pass", @response.headers["X-Cascade"]
+    delete "/posts/1/comments"
+    assert_equal "pass", @response.headers["X-Cascade"]
   end
 
   def test_resource_routes_only_create_update_destroy
     draw do
-      resource  :past, :only => :destroy
-      resource  :present, :only => :update
-      resource  :future, :only => :create
+      resource  :past, only: :destroy
+      resource  :present, only: :update
+      resource  :future, only: :create
     end
 
-    delete '/past'
-    assert_equal 'pasts#destroy', @response.body
-    assert_equal '/past', past_path
+    delete "/past"
+    assert_equal "pasts#destroy", @response.body
+    assert_equal "/past", past_path
 
-    patch '/present'
-    assert_equal 'presents#update', @response.body
-    assert_equal '/present', present_path
+    patch "/present"
+    assert_equal "presents#update", @response.body
+    assert_equal "/present", present_path
 
-    put '/present'
-    assert_equal 'presents#update', @response.body
-    assert_equal '/present', present_path
+    put "/present"
+    assert_equal "presents#update", @response.body
+    assert_equal "/present", present_path
 
-    post '/future'
-    assert_equal 'futures#create', @response.body
-    assert_equal '/future', future_path
+    post "/future"
+    assert_equal "futures#create", @response.body
+    assert_equal "/future", future_path
   end
 
   def test_resources_routes_only_create_update_destroy
     draw do
-      resources :relationships, :only => [:create, :destroy]
-      resources :friendships,   :only => [:update]
+      resources :relationships, only: [:create, :destroy]
+      resources :friendships,   only: [:update]
     end
 
-    post '/relationships'
-    assert_equal 'relationships#create', @response.body
-    assert_equal '/relationships', relationships_path
+    post "/relationships"
+    assert_equal "relationships#create", @response.body
+    assert_equal "/relationships", relationships_path
 
-    delete '/relationships/1'
-    assert_equal 'relationships#destroy', @response.body
-    assert_equal '/relationships/1', relationship_path(1)
+    delete "/relationships/1"
+    assert_equal "relationships#destroy", @response.body
+    assert_equal "/relationships/1", relationship_path(1)
 
-    patch '/friendships/1'
-    assert_equal 'friendships#update', @response.body
-    assert_equal '/friendships/1', friendship_path(1)
+    patch "/friendships/1"
+    assert_equal "friendships#update", @response.body
+    assert_equal "/friendships/1", friendship_path(1)
 
-    put '/friendships/1'
-    assert_equal 'friendships#update', @response.body
-    assert_equal '/friendships/1', friendship_path(1)
+    put "/friendships/1"
+    assert_equal "friendships#update", @response.body
+    assert_equal "/friendships/1", friendship_path(1)
   end
 
   def test_resource_with_slugs_in_ids
@@ -931,153 +936,153 @@ class TestRoutingMapper < ActionDispatch::IntegrationTest
       resources :posts
     end
 
-    get '/posts/rails-rocks'
-    assert_equal 'posts#show', @response.body
-    assert_equal '/posts/rails-rocks', post_path(:id => 'rails-rocks')
+    get "/posts/rails-rocks"
+    assert_equal "posts#show", @response.body
+    assert_equal "/posts/rails-rocks", post_path(id: "rails-rocks")
   end
 
   def test_resources_for_uncountable_names
     draw do
       resources :sheep do
-        get "_it", :on => :member
+        get "_it", on: :member
       end
     end
 
-    assert_equal '/sheep', sheep_index_path
-    assert_equal '/sheep/1', sheep_path(1)
-    assert_equal '/sheep/new', new_sheep_path
-    assert_equal '/sheep/1/edit', edit_sheep_path(1)
-    assert_equal '/sheep/1/_it', _it_sheep_path(1)
+    assert_equal "/sheep", sheep_index_path
+    assert_equal "/sheep/1", sheep_path(1)
+    assert_equal "/sheep/new", new_sheep_path
+    assert_equal "/sheep/1/edit", edit_sheep_path(1)
+    assert_equal "/sheep/1/_it", _it_sheep_path(1)
   end
 
   def test_resource_does_not_modify_passed_options
-    options = {:id => /.+?/, :format => /json|xml/}
+    options = { id: /.+?/, format: /json|xml/ }
     draw { resource :user, options }
-    assert_equal({:id => /.+?/, :format => /json|xml/}, options)
+    assert_equal({ id: /.+?/, format: /json|xml/ }, options)
   end
 
   def test_resources_does_not_modify_passed_options
-    options = {:id => /.+?/, :format => /json|xml/}
+    options = { id: /.+?/, format: /json|xml/ }
     draw { resources :users, options }
-    assert_equal({:id => /.+?/, :format => /json|xml/}, options)
+    assert_equal({ id: /.+?/, format: /json|xml/ }, options)
   end
 
   def test_path_names
     draw do
-      scope 'pt', :as => 'pt' do
-        resources :projects, :path_names => { :edit => 'editar', :new => 'novo' }, :path => 'projetos'
-        resource  :admin, :path_names => { :new => 'novo', :activate => 'ativar' }, :path => 'administrador' do
-          put :activate, :on => :member
+      scope "pt", as: "pt" do
+        resources :projects, path_names: { edit: "editar", new: "novo" }, path: "projetos"
+        resource  :admin, path_names: { new: "novo", activate: "ativar" }, path: "administrador" do
+          put :activate, on: :member
         end
       end
     end
 
-    get '/pt/projetos'
-    assert_equal 'projects#index', @response.body
-    assert_equal '/pt/projetos', pt_projects_path
+    get "/pt/projetos"
+    assert_equal "projects#index", @response.body
+    assert_equal "/pt/projetos", pt_projects_path
 
-    get '/pt/projetos/1/editar'
-    assert_equal 'projects#edit', @response.body
-    assert_equal '/pt/projetos/1/editar', edit_pt_project_path(1)
+    get "/pt/projetos/1/editar"
+    assert_equal "projects#edit", @response.body
+    assert_equal "/pt/projetos/1/editar", edit_pt_project_path(1)
 
-    get '/pt/administrador'
-    assert_equal 'admins#show', @response.body
-    assert_equal '/pt/administrador', pt_admin_path
+    get "/pt/administrador"
+    assert_equal "admins#show", @response.body
+    assert_equal "/pt/administrador", pt_admin_path
 
-    get '/pt/administrador/novo'
-    assert_equal 'admins#new', @response.body
-    assert_equal '/pt/administrador/novo', new_pt_admin_path
+    get "/pt/administrador/novo"
+    assert_equal "admins#new", @response.body
+    assert_equal "/pt/administrador/novo", new_pt_admin_path
 
-    put '/pt/administrador/ativar'
-    assert_equal 'admins#activate', @response.body
-    assert_equal '/pt/administrador/ativar', activate_pt_admin_path
+    put "/pt/administrador/ativar"
+    assert_equal "admins#activate", @response.body
+    assert_equal "/pt/administrador/ativar", activate_pt_admin_path
   end
 
   def test_path_option_override
     draw do
-      scope 'pt', :as => 'pt' do
-        resources :projects, :path_names => { :new => 'novo' }, :path => 'projetos' do
-          put :close, :on => :member, :path => 'fechar'
-          get :open, :on => :new, :path => 'abrir'
+      scope "pt", as: "pt" do
+        resources :projects, path_names: { new: "novo" }, path: "projetos" do
+          put :close, on: :member, path: "fechar"
+          get :open, on: :new, path: "abrir"
         end
       end
     end
 
-    get '/pt/projetos/novo/abrir'
-    assert_equal 'projects#open', @response.body
-    assert_equal '/pt/projetos/novo/abrir', open_new_pt_project_path
+    get "/pt/projetos/novo/abrir"
+    assert_equal "projects#open", @response.body
+    assert_equal "/pt/projetos/novo/abrir", open_new_pt_project_path
 
-    put '/pt/projetos/1/fechar'
-    assert_equal 'projects#close', @response.body
-    assert_equal '/pt/projetos/1/fechar', close_pt_project_path(1)
+    put "/pt/projetos/1/fechar"
+    assert_equal "projects#close", @response.body
+    assert_equal "/pt/projetos/1/fechar", close_pt_project_path(1)
   end
 
   def test_sprockets
     draw do
-      get 'sprockets.js' => ::TestRoutingMapper::SprocketsApp
+      get "sprockets.js" => ::TestRoutingMapper::SprocketsApp
     end
 
-    get '/sprockets.js'
-    assert_equal 'javascripts', @response.body
+    get "/sprockets.js"
+    assert_equal "javascripts", @response.body
   end
 
   def test_update_person_route
     draw do
-      get 'people/:id/update', :to => 'people#update', :as => :update_person
+      get "people/:id/update", to: "people#update", as: :update_person
     end
 
-    get '/people/1/update'
-    assert_equal 'people#update', @response.body
+    get "/people/1/update"
+    assert_equal "people#update", @response.body
 
-    assert_equal '/people/1/update', update_person_path(:id => 1)
+    assert_equal "/people/1/update", update_person_path(id: 1)
   end
 
   def test_update_project_person
     draw do
-      get '/projects/:project_id/people/:id/update', :to => 'people#update', :as => :update_project_person
+      get "/projects/:project_id/people/:id/update", to: "people#update", as: :update_project_person
     end
 
-    get '/projects/1/people/2/update'
-    assert_equal 'people#update', @response.body
+    get "/projects/1/people/2/update"
+    assert_equal "people#update", @response.body
 
-    assert_equal '/projects/1/people/2/update', update_project_person_path(:project_id => 1, :id => 2)
+    assert_equal "/projects/1/people/2/update", update_project_person_path(project_id: 1, id: 2)
   end
 
   def test_forum_products
     draw do
       namespace :forum do
-        resources :products, :path => '' do
+        resources :products, path: "" do
           resources :questions
         end
       end
     end
 
-    get '/forum'
-    assert_equal 'forum/products#index', @response.body
-    assert_equal '/forum', forum_products_path
+    get "/forum"
+    assert_equal "forum/products#index", @response.body
+    assert_equal "/forum", forum_products_path
 
-    get '/forum/basecamp'
-    assert_equal 'forum/products#show', @response.body
-    assert_equal '/forum/basecamp', forum_product_path(:id => 'basecamp')
+    get "/forum/basecamp"
+    assert_equal "forum/products#show", @response.body
+    assert_equal "/forum/basecamp", forum_product_path(id: "basecamp")
 
-    get '/forum/basecamp/questions'
-    assert_equal 'forum/questions#index', @response.body
-    assert_equal '/forum/basecamp/questions', forum_product_questions_path(:product_id => 'basecamp')
+    get "/forum/basecamp/questions"
+    assert_equal "forum/questions#index", @response.body
+    assert_equal "/forum/basecamp/questions", forum_product_questions_path(product_id: "basecamp")
 
-    get '/forum/basecamp/questions/1'
-    assert_equal 'forum/questions#show', @response.body
-    assert_equal '/forum/basecamp/questions/1', forum_product_question_path(:product_id => 'basecamp', :id => 1)
+    get "/forum/basecamp/questions/1"
+    assert_equal "forum/questions#show", @response.body
+    assert_equal "/forum/basecamp/questions/1", forum_product_question_path(product_id: "basecamp", id: 1)
   end
 
   def test_articles_perma
     draw do
-      get 'articles/:year/:month/:day/:title', :to => "articles#show", :as => :article
+      get "articles/:year/:month/:day/:title", to: "articles#show", as: :article
     end
 
-    get '/articles/2009/08/18/rails-3'
-    assert_equal 'articles#show', @response.body
+    get "/articles/2009/08/18/rails-3"
+    assert_equal "articles#show", @response.body
 
-    assert_equal '/articles/2009/8/18/rails-3', article_path(:year => 2009, :month => 8, :day => 18, :title => 'rails-3')
+    assert_equal "/articles/2009/8/18/rails-3", article_path(year: 2009, month: 8, day: 18, title: "rails-3")
   end
 
   def test_account_namespace
@@ -1087,17 +1092,17 @@ class TestRoutingMapper < ActionDispatch::IntegrationTest
       end
     end
 
-    get '/account/subscription'
-    assert_equal 'account/subscriptions#show', @response.body
-    assert_equal '/account/subscription', account_subscription_path
+    get "/account/subscription"
+    assert_equal "account/subscriptions#show", @response.body
+    assert_equal "/account/subscription", account_subscription_path
 
-    get '/account/credit'
-    assert_equal 'account/credits#show', @response.body
-    assert_equal '/account/credit', account_credit_path
+    get "/account/credit"
+    assert_equal "account/credits#show", @response.body
+    assert_equal "/account/credit", account_credit_path
 
-    get '/account/credit_card'
-    assert_equal 'account/credit_cards#show', @response.body
-    assert_equal '/account/credit_card', account_credit_card_path
+    get "/account/credit_card"
+    assert_equal "account/credit_cards#show", @response.body
+    assert_equal "/account/credit_card", account_credit_card_path
   end
 
   def test_nested_namespace
@@ -1109,9 +1114,9 @@ class TestRoutingMapper < ActionDispatch::IntegrationTest
       end
     end
 
-    get '/account/admin/subscription'
-    assert_equal 'account/admin/subscriptions#show', @response.body
-    assert_equal '/account/admin/subscription', account_admin_subscription_path
+    get "/account/admin/subscription"
+    assert_equal "account/admin/subscriptions#show", @response.body
+    assert_equal "/account/admin/subscription", account_admin_subscription_path
   end
 
   def test_namespace_nested_in_resources
@@ -1127,155 +1132,155 @@ class TestRoutingMapper < ActionDispatch::IntegrationTest
       end
     end
 
-    get '/clients/1/google/account'
-    assert_equal '/clients/1/google/account', client_google_account_path(1)
-    assert_equal 'google/accounts#show', @response.body
+    get "/clients/1/google/account"
+    assert_equal "/clients/1/google/account", client_google_account_path(1)
+    assert_equal "google/accounts#show", @response.body
 
-    get '/clients/1/google/account/secret/info'
-    assert_equal '/clients/1/google/account/secret/info', client_google_account_secret_info_path(1)
-    assert_equal 'google/secret/infos#show', @response.body
+    get "/clients/1/google/account/secret/info"
+    assert_equal "/clients/1/google/account/secret/info", client_google_account_secret_info_path(1)
+    assert_equal "google/secret/infos#show", @response.body
   end
 
   def test_namespace_with_options
     draw do
-      namespace :users, :path => 'usuarios' do
-        root :to => 'home#index'
+      namespace :users, path: "usuarios" do
+        root to: "home#index"
       end
     end
 
-    get '/usuarios'
-    assert_equal '/usuarios', users_root_path
-    assert_equal 'users/home#index', @response.body
+    get "/usuarios"
+    assert_equal "/usuarios", users_root_path
+    assert_equal "users/home#index", @response.body
   end
 
   def test_namespaced_shallow_routes_with_module_option
     draw do
-      namespace :foo, module: 'bar' do
+      namespace :foo, module: "bar" do
         resources :posts, only: [:index, :show] do
           resources :comments, only: [:index, :show], shallow: true
         end
       end
     end
 
-    get '/foo/posts'
-    assert_equal '/foo/posts', foo_posts_path
-    assert_equal 'bar/posts#index', @response.body
+    get "/foo/posts"
+    assert_equal "/foo/posts", foo_posts_path
+    assert_equal "bar/posts#index", @response.body
 
-    get '/foo/posts/1'
-    assert_equal '/foo/posts/1', foo_post_path('1')
-    assert_equal 'bar/posts#show', @response.body
+    get "/foo/posts/1"
+    assert_equal "/foo/posts/1", foo_post_path("1")
+    assert_equal "bar/posts#show", @response.body
 
-    get '/foo/posts/1/comments'
-    assert_equal '/foo/posts/1/comments', foo_post_comments_path('1')
-    assert_equal 'bar/comments#index', @response.body
+    get "/foo/posts/1/comments"
+    assert_equal "/foo/posts/1/comments", foo_post_comments_path("1")
+    assert_equal "bar/comments#index", @response.body
 
-    get '/foo/comments/2'
-    assert_equal '/foo/comments/2', foo_comment_path('2')
-    assert_equal 'bar/comments#show', @response.body
+    get "/foo/comments/2"
+    assert_equal "/foo/comments/2", foo_comment_path("2")
+    assert_equal "bar/comments#show", @response.body
   end
 
   def test_namespaced_shallow_routes_with_path_option
     draw do
-      namespace :foo, path: 'bar' do
+      namespace :foo, path: "bar" do
         resources :posts, only: [:index, :show] do
           resources :comments, only: [:index, :show], shallow: true
         end
       end
     end
 
-    get '/bar/posts'
-    assert_equal '/bar/posts', foo_posts_path
-    assert_equal 'foo/posts#index', @response.body
+    get "/bar/posts"
+    assert_equal "/bar/posts", foo_posts_path
+    assert_equal "foo/posts#index", @response.body
 
-    get '/bar/posts/1'
-    assert_equal '/bar/posts/1', foo_post_path('1')
-    assert_equal 'foo/posts#show', @response.body
+    get "/bar/posts/1"
+    assert_equal "/bar/posts/1", foo_post_path("1")
+    assert_equal "foo/posts#show", @response.body
 
-    get '/bar/posts/1/comments'
-    assert_equal '/bar/posts/1/comments', foo_post_comments_path('1')
-    assert_equal 'foo/comments#index', @response.body
+    get "/bar/posts/1/comments"
+    assert_equal "/bar/posts/1/comments", foo_post_comments_path("1")
+    assert_equal "foo/comments#index", @response.body
 
-    get '/bar/comments/2'
-    assert_equal '/bar/comments/2', foo_comment_path('2')
-    assert_equal 'foo/comments#show', @response.body
+    get "/bar/comments/2"
+    assert_equal "/bar/comments/2", foo_comment_path("2")
+    assert_equal "foo/comments#show", @response.body
   end
 
   def test_namespaced_shallow_routes_with_as_option
     draw do
-      namespace :foo, as: 'bar' do
+      namespace :foo, as: "bar" do
         resources :posts, only: [:index, :show] do
           resources :comments, only: [:index, :show], shallow: true
         end
       end
     end
 
-    get '/foo/posts'
-    assert_equal '/foo/posts', bar_posts_path
-    assert_equal 'foo/posts#index', @response.body
+    get "/foo/posts"
+    assert_equal "/foo/posts", bar_posts_path
+    assert_equal "foo/posts#index", @response.body
 
-    get '/foo/posts/1'
-    assert_equal '/foo/posts/1', bar_post_path('1')
-    assert_equal 'foo/posts#show', @response.body
+    get "/foo/posts/1"
+    assert_equal "/foo/posts/1", bar_post_path("1")
+    assert_equal "foo/posts#show", @response.body
 
-    get '/foo/posts/1/comments'
-    assert_equal '/foo/posts/1/comments', bar_post_comments_path('1')
-    assert_equal 'foo/comments#index', @response.body
+    get "/foo/posts/1/comments"
+    assert_equal "/foo/posts/1/comments", bar_post_comments_path("1")
+    assert_equal "foo/comments#index", @response.body
 
-    get '/foo/comments/2'
-    assert_equal '/foo/comments/2', bar_comment_path('2')
-    assert_equal 'foo/comments#show', @response.body
+    get "/foo/comments/2"
+    assert_equal "/foo/comments/2", bar_comment_path("2")
+    assert_equal "foo/comments#show", @response.body
   end
 
   def test_namespaced_shallow_routes_with_shallow_path_option
     draw do
-      namespace :foo, shallow_path: 'bar' do
+      namespace :foo, shallow_path: "bar" do
         resources :posts, only: [:index, :show] do
           resources :comments, only: [:index, :show], shallow: true
         end
       end
     end
 
-    get '/foo/posts'
-    assert_equal '/foo/posts', foo_posts_path
-    assert_equal 'foo/posts#index', @response.body
+    get "/foo/posts"
+    assert_equal "/foo/posts", foo_posts_path
+    assert_equal "foo/posts#index", @response.body
 
-    get '/foo/posts/1'
-    assert_equal '/foo/posts/1', foo_post_path('1')
-    assert_equal 'foo/posts#show', @response.body
+    get "/foo/posts/1"
+    assert_equal "/foo/posts/1", foo_post_path("1")
+    assert_equal "foo/posts#show", @response.body
 
-    get '/foo/posts/1/comments'
-    assert_equal '/foo/posts/1/comments', foo_post_comments_path('1')
-    assert_equal 'foo/comments#index', @response.body
+    get "/foo/posts/1/comments"
+    assert_equal "/foo/posts/1/comments", foo_post_comments_path("1")
+    assert_equal "foo/comments#index", @response.body
 
-    get '/bar/comments/2'
-    assert_equal '/bar/comments/2', foo_comment_path('2')
-    assert_equal 'foo/comments#show', @response.body
+    get "/bar/comments/2"
+    assert_equal "/bar/comments/2", foo_comment_path("2")
+    assert_equal "foo/comments#show", @response.body
   end
 
   def test_namespaced_shallow_routes_with_shallow_prefix_option
     draw do
-      namespace :foo, shallow_prefix: 'bar' do
+      namespace :foo, shallow_prefix: "bar" do
         resources :posts, only: [:index, :show] do
           resources :comments, only: [:index, :show], shallow: true
         end
       end
     end
 
-    get '/foo/posts'
-    assert_equal '/foo/posts', foo_posts_path
-    assert_equal 'foo/posts#index', @response.body
+    get "/foo/posts"
+    assert_equal "/foo/posts", foo_posts_path
+    assert_equal "foo/posts#index", @response.body
 
-    get '/foo/posts/1'
-    assert_equal '/foo/posts/1', foo_post_path('1')
-    assert_equal 'foo/posts#show', @response.body
+    get "/foo/posts/1"
+    assert_equal "/foo/posts/1", foo_post_path("1")
+    assert_equal "foo/posts#show", @response.body
 
-    get '/foo/posts/1/comments'
-    assert_equal '/foo/posts/1/comments', foo_post_comments_path('1')
-    assert_equal 'foo/comments#index', @response.body
+    get "/foo/posts/1/comments"
+    assert_equal "/foo/posts/1/comments", foo_post_comments_path("1")
+    assert_equal "foo/comments#index", @response.body
 
-    get '/foo/comments/2'
-    assert_equal '/foo/comments/2', bar_comment_path('2')
-    assert_equal 'foo/comments#show', @response.body
+    get "/foo/comments/2"
+    assert_equal "/foo/comments/2", bar_comment_path("2")
+    assert_equal "foo/comments#show", @response.body
   end
 
   def test_namespace_containing_numbers
@@ -1285,81 +1290,81 @@ class TestRoutingMapper < ActionDispatch::IntegrationTest
       end
     end
 
-    get '/v2/subscriptions'
-    assert_equal 'v2/subscriptions#index', @response.body
-    assert_equal '/v2/subscriptions', v2_subscriptions_path
+    get "/v2/subscriptions"
+    assert_equal "v2/subscriptions#index", @response.body
+    assert_equal "/v2/subscriptions", v2_subscriptions_path
   end
 
   def test_articles_with_id
     draw do
       controller :articles do
-        scope '/articles', :as => 'article' do
-          scope :path => '/:title', :title => /[a-z]+/, :as => :with_title do
-            get '/:id', :action => :with_id, :as => ""
+        scope "/articles", as: "article" do
+          scope path: "/:title", title: /[a-z]+/, as: :with_title do
+            get "/:id", action: :with_id, as: ""
           end
         end
       end
     end
 
-    get '/articles/rails/1'
-    assert_equal 'articles#with_id', @response.body
+    get "/articles/rails/1"
+    assert_equal "articles#with_id", @response.body
 
-    get '/articles/123/1'
-    assert_equal 'pass', @response.headers['X-Cascade']
+    get "/articles/123/1"
+    assert_equal "pass", @response.headers["X-Cascade"]
 
-    assert_equal '/articles/rails/1', article_with_title_path(:title => 'rails', :id => 1)
+    assert_equal "/articles/rails/1", article_with_title_path(title: "rails", id: 1)
   end
 
   def test_access_token_rooms
     draw do
-      scope ':access_token', :constraints => { :access_token => /\w{5,5}/ } do
+      scope ":access_token", constraints: { access_token: /\w{5,5}/ } do
         resources :rooms
       end
     end
 
-    get '/12345/rooms'
-    assert_equal 'rooms#index', @response.body
+    get "/12345/rooms"
+    assert_equal "rooms#index", @response.body
 
-    get '/12345/rooms/1'
-    assert_equal 'rooms#show', @response.body
+    get "/12345/rooms/1"
+    assert_equal "rooms#show", @response.body
 
-    get '/12345/rooms/1/edit'
-    assert_equal 'rooms#edit', @response.body
+    get "/12345/rooms/1/edit"
+    assert_equal "rooms#edit", @response.body
   end
 
   def test_root
     draw do
-      root :to => 'projects#index'
+      root to: "projects#index"
     end
 
-    assert_equal '/', root_path
-    get '/'
-    assert_equal 'projects#index', @response.body
+    assert_equal "/", root_path
+    get "/"
+    assert_equal "projects#index", @response.body
   end
 
   def test_scoped_root
     draw do
-      scope '(:locale)', :locale => /en|pl/ do
-        root :to => 'projects#index'
+      scope "(:locale)", locale: /en|pl/ do
+        root to: "projects#index"
       end
     end
 
-    assert_equal '/en', root_path(:locale => 'en')
-    get '/en'
-    assert_equal 'projects#index', @response.body
+    assert_equal "/en", root_path(locale: "en")
+    get "/en"
+    assert_equal "projects#index", @response.body
   end
 
   def test_scoped_root_as_name
     draw do
-      scope '(:locale)', :locale => /en|pl/ do
-        root :to => 'projects#index', :as => 'projects'
+      scope "(:locale)", locale: /en|pl/ do
+        root to: "projects#index", as: "projects"
       end
     end
 
-    assert_equal '/en', projects_path(:locale => 'en')
-    assert_equal '/', projects_path
-    get '/en'
-    assert_equal 'projects#index', @response.body
+    assert_equal "/en", projects_path(locale: "en")
+    assert_equal "/", projects_path
+    get "/en"
+    assert_equal "projects#index", @response.body
   end
 
   def test_scope_with_format_option
@@ -1377,10 +1382,10 @@ class TestRoutingMapper < ActionDispatch::IntegrationTest
     assert_equal "/scoped/index", no_format_scoped_path
     assert_equal "/scoped/index?format=html", no_format_scoped_path(format: "html")
 
-    get '/scoped/index'
+    get "/scoped/index"
     assert_equal "scoped#index", @response.body
 
-    get '/scoped/index.html'
+    get "/scoped/index.html"
     assert_equal "Not Found", @response.body
   end
 
@@ -1415,63 +1420,63 @@ class TestRoutingMapper < ActionDispatch::IntegrationTest
 
   def test_index
     draw do
-      get '/info' => 'projects#info', :as => 'info'
+      get "/info" => "projects#info", :as => "info"
     end
 
-    assert_equal '/info', info_path
-    get '/info'
-    assert_equal 'projects#info', @response.body
+    assert_equal "/info", info_path
+    get "/info"
+    assert_equal "projects#info", @response.body
   end
 
   def test_match_with_many_paths_containing_a_slash
     draw do
-      get 'get/first', 'get/second', 'get/third', :to => 'get#show'
+      get "get/first", "get/second", "get/third", to: "get#show"
     end
 
-    get '/get/first'
-    assert_equal 'get#show', @response.body
+    get "/get/first"
+    assert_equal "get#show", @response.body
 
-    get '/get/second'
-    assert_equal 'get#show', @response.body
+    get "/get/second"
+    assert_equal "get#show", @response.body
 
-    get '/get/third'
-    assert_equal 'get#show', @response.body
+    get "/get/third"
+    assert_equal "get#show", @response.body
   end
 
   def test_match_shorthand_with_no_scope
     draw do
-      get 'account/overview'
+      get "account/overview"
     end
 
-    assert_equal '/account/overview', account_overview_path
-    get '/account/overview'
-    assert_equal 'account#overview', @response.body
+    assert_equal "/account/overview", account_overview_path
+    get "/account/overview"
+    assert_equal "account#overview", @response.body
   end
 
   def test_match_shorthand_inside_namespace
     draw do
       namespace :account do
-        get 'shorthand'
+        get "shorthand"
       end
     end
 
-    assert_equal '/account/shorthand', account_shorthand_path
-    get '/account/shorthand'
-    assert_equal 'account#shorthand', @response.body
+    assert_equal "/account/shorthand", account_shorthand_path
+    get "/account/shorthand"
+    assert_equal "account#shorthand", @response.body
   end
 
   def test_match_shorthand_with_multiple_paths_inside_namespace
     draw do
       namespace :proposals do
-        put 'activate', 'inactivate'
+        put "activate", "inactivate"
       end
     end
 
-    put '/proposals/activate'
-    assert_equal 'proposals#activate', @response.body
+    put "/proposals/activate"
+    assert_equal "proposals#activate", @response.body
 
-    put '/proposals/inactivate'
-    assert_equal 'proposals#inactivate', @response.body
+    put "/proposals/inactivate"
+    assert_equal "proposals#inactivate", @response.body
   end
 
   def test_match_shorthand_inside_namespace_with_controller
@@ -1481,130 +1486,130 @@ class TestRoutingMapper < ActionDispatch::IntegrationTest
       end
     end
 
-    assert_equal '/api/products/list', api_products_list_path
-    get '/api/products/list'
-    assert_equal 'api/products#list', @response.body
+    assert_equal "/api/products/list", api_products_list_path
+    get "/api/products/list"
+    assert_equal "api/products#list", @response.body
   end
 
   def test_match_shorthand_inside_scope_with_variables_with_controller
     draw do
-      scope ':locale' do
-        match 'questions/new', via: [:get]
+      scope ":locale" do
+        match "questions/new", via: [:get]
       end
     end
 
-    get '/de/questions/new'
-    assert_equal 'questions#new', @response.body
-    assert_equal 'de', @request.params[:locale]
+    get "/de/questions/new"
+    assert_equal "questions#new", @response.body
+    assert_equal "de", @request.params[:locale]
   end
 
   def test_match_shorthand_inside_nested_namespaces_and_scopes_with_controller
     draw do
       namespace :api do
         namespace :v3 do
-          scope ':locale' do
+          scope ":locale" do
             get "products/list"
           end
         end
       end
     end
 
-    get '/api/v3/en/products/list'
-    assert_equal 'api/v3/products#list', @response.body
+    get "/api/v3/en/products/list"
+    assert_equal "api/v3/products#list", @response.body
   end
 
   def test_not_matching_shorthand_with_dynamic_parameters
     draw do
       ActiveSupport::Deprecation.silence do
-        get ':controller/:action/admin'
+        get ":controller/:action/admin"
       end
     end
 
-    get '/finances/overview/admin'
-    assert_equal 'finances#overview', @response.body
+    get "/finances/overview/admin"
+    assert_equal "finances#overview", @response.body
   end
 
   def test_controller_option_with_nesting_and_leading_slash
     draw do
-      scope '/job', controller: 'job' do
-        scope ':id', action: 'manage_applicant' do
+      scope "/job", controller: "job" do
+        scope ":id", action: "manage_applicant" do
           get "/active"
         end
       end
     end
 
-    get '/job/5/active'
-    assert_equal 'job#manage_applicant', @response.body
+    get "/job/5/active"
+    assert_equal "job#manage_applicant", @response.body
   end
 
   def test_dynamically_generated_helpers_on_collection_do_not_clobber_resources_url_helper
     draw do
       resources :replies do
         collection do
-          get 'page/:page' => 'replies#index', :page => %r{\d+}
-          get ':page' => 'replies#index', :page => %r{\d+}
+          get "page/:page" => "replies#index", :page => %r{\d+}
+          get ":page" => "replies#index", :page => %r{\d+}
         end
       end
     end
 
-    assert_equal '/replies', replies_path
+    assert_equal "/replies", replies_path
   end
 
   def test_scoped_controller_with_namespace_and_action
     draw do
       namespace :account do
         ActiveSupport::Deprecation.silence do
-          get ':action/callback', :action => /twitter|github/, :controller => "callbacks", :as => :callback
+          get ":action/callback", action: /twitter|github/, controller: "callbacks", as: :callback
         end
       end
     end
 
-    assert_equal '/account/twitter/callback', account_callback_path("twitter")
-    get '/account/twitter/callback'
-    assert_equal 'account/callbacks#twitter', @response.body
+    assert_equal "/account/twitter/callback", account_callback_path("twitter")
+    get "/account/twitter/callback"
+    assert_equal "account/callbacks#twitter", @response.body
 
-    get '/account/whatever/callback'
-    assert_equal 'Not Found', @response.body
+    get "/account/whatever/callback"
+    assert_equal "Not Found", @response.body
   end
 
   def test_convention_match_nested_and_with_leading_slash
     draw do
-      get '/account/nested/overview'
+      get "/account/nested/overview"
     end
 
-    assert_equal '/account/nested/overview', account_nested_overview_path
-    get '/account/nested/overview'
-    assert_equal 'account/nested#overview', @response.body
+    assert_equal "/account/nested/overview", account_nested_overview_path
+    get "/account/nested/overview"
+    assert_equal "account/nested#overview", @response.body
   end
 
   def test_convention_with_explicit_end
     draw do
-      get 'sign_in' => "sessions#new"
+      get "sign_in" => "sessions#new"
     end
 
-    get '/sign_in'
-    assert_equal 'sessions#new', @response.body
-    assert_equal '/sign_in', sign_in_path
+    get "/sign_in"
+    assert_equal "sessions#new", @response.body
+    assert_equal "/sign_in", sign_in_path
   end
 
   def test_redirect_with_complete_url_and_status
     draw do
-      get 'account/google' => redirect('http://www.google.com/', :status => 302)
+      get "account/google" => redirect("http://www.google.com/", status: 302)
     end
 
-    get '/account/google'
-    verify_redirect 'http://www.google.com/', 302
+    get "/account/google"
+    verify_redirect "http://www.google.com/", 302
   end
 
   def test_redirect_with_port
     draw do
-      get 'account/login', :to => redirect("/login")
+      get "account/login", to: redirect("/login")
     end
 
-    previous_host, self.host = self.host, 'www.example.com:3000'
+    previous_host, self.host = host, "www.example.com:3000"
 
-    get '/account/login'
-    verify_redirect 'http://www.example.com:3000/login'
+    get "/account/login"
+    verify_redirect "http://www.example.com:3000/login"
   ensure
     self.host = previous_host
   end
@@ -1612,240 +1617,276 @@ class TestRoutingMapper < ActionDispatch::IntegrationTest
   def test_normalize_namespaced_matches
     draw do
       namespace :account do
-        get 'description', :action => :description, :as => "description"
+        get "description", action: :description, as: "description"
       end
     end
 
-    assert_equal '/account/description', account_description_path
+    assert_equal "/account/description", account_description_path
 
-    get '/account/description'
-    assert_equal 'account#description', @response.body
+    get "/account/description"
+    assert_equal "account#description", @response.body
   end
 
   def test_namespaced_roots
     draw do
       namespace :account do
-        root :to => "account#index"
+        root to: "account#index"
       end
     end
 
-    assert_equal '/account', account_root_path
-    get '/account'
-    assert_equal 'account/account#index', @response.body
+    assert_equal "/account", account_root_path
+    get "/account"
+    assert_equal "account/account#index", @response.body
   end
 
   def test_optional_scoped_root
     draw do
-      scope '(:locale)', :locale => /en|pl/ do
-        root :to => 'projects#index'
+      scope "(:locale)", locale: /en|pl/ do
+        root to: "projects#index"
       end
     end
 
-    assert_equal '/en', root_path("en")
-    get '/en'
-    assert_equal 'projects#index', @response.body
+    assert_equal "/en", root_path("en")
+    get "/en"
+    assert_equal "projects#index", @response.body
   end
 
   def test_optional_scoped_path
     draw do
-      scope '(:locale)', :locale => /en|pl/ do
+      scope "(:locale)", locale: /en|pl/ do
         resources :descriptions
       end
     end
 
-    assert_equal '/en/descriptions', descriptions_path("en")
-    assert_equal '/descriptions', descriptions_path(nil)
-    assert_equal '/en/descriptions/1', description_path("en", 1)
-    assert_equal '/descriptions/1', description_path(nil, 1)
+    assert_equal "/en/descriptions", descriptions_path("en")
+    assert_equal "/descriptions", descriptions_path(nil)
+    assert_equal "/en/descriptions/1", description_path("en", 1)
+    assert_equal "/descriptions/1", description_path(nil, 1)
 
-    get '/en/descriptions'
-    assert_equal 'descriptions#index', @response.body
+    get "/en/descriptions"
+    assert_equal "descriptions#index", @response.body
 
-    get '/descriptions'
-    assert_equal 'descriptions#index', @response.body
+    get "/descriptions"
+    assert_equal "descriptions#index", @response.body
 
-    get '/en/descriptions/1'
-    assert_equal 'descriptions#show', @response.body
+    get "/en/descriptions/1"
+    assert_equal "descriptions#show", @response.body
 
-    get '/descriptions/1'
-    assert_equal 'descriptions#show', @response.body
+    get "/descriptions/1"
+    assert_equal "descriptions#show", @response.body
   end
 
   def test_nested_optional_scoped_path
     draw do
       namespace :admin do
-        scope '(:locale)', :locale => /en|pl/ do
+        scope "(:locale)", locale: /en|pl/ do
           resources :descriptions
         end
       end
     end
 
-    assert_equal '/admin/en/descriptions', admin_descriptions_path("en")
-    assert_equal '/admin/descriptions', admin_descriptions_path(nil)
-    assert_equal '/admin/en/descriptions/1', admin_description_path("en", 1)
-    assert_equal '/admin/descriptions/1', admin_description_path(nil, 1)
+    assert_equal "/admin/en/descriptions", admin_descriptions_path("en")
+    assert_equal "/admin/descriptions", admin_descriptions_path(nil)
+    assert_equal "/admin/en/descriptions/1", admin_description_path("en", 1)
+    assert_equal "/admin/descriptions/1", admin_description_path(nil, 1)
 
-    get '/admin/en/descriptions'
-    assert_equal 'admin/descriptions#index', @response.body
+    get "/admin/en/descriptions"
+    assert_equal "admin/descriptions#index", @response.body
 
-    get '/admin/descriptions'
-    assert_equal 'admin/descriptions#index', @response.body
+    get "/admin/descriptions"
+    assert_equal "admin/descriptions#index", @response.body
 
-    get '/admin/en/descriptions/1'
-    assert_equal 'admin/descriptions#show', @response.body
+    get "/admin/en/descriptions/1"
+    assert_equal "admin/descriptions#show", @response.body
 
-    get '/admin/descriptions/1'
-    assert_equal 'admin/descriptions#show', @response.body
+    get "/admin/descriptions/1"
+    assert_equal "admin/descriptions#show", @response.body
   end
 
   def test_nested_optional_path_shorthand
     draw do
-      scope '(:locale)', :locale => /en|pl/ do
+      scope "(:locale)", locale: /en|pl/ do
         get "registrations/new"
       end
     end
 
-    get '/registrations/new'
+    get "/registrations/new"
     assert_nil @request.params[:locale]
 
-    get '/en/registrations/new'
-    assert_equal 'en', @request.params[:locale]
+    get "/en/registrations/new"
+    assert_equal "en", @request.params[:locale]
   end
 
   def test_default_string_params
     draw do
-      get 'inline_pages/(:id)', :to => 'pages#show', :id => 'home'
-      get 'default_pages/(:id)', :to => 'pages#show', :defaults => { :id => 'home' }
+      get "inline_pages/(:id)", to: "pages#show", id: "home"
+      get "default_pages/(:id)", to: "pages#show", defaults: { id: "home" }
 
-      defaults :id => 'home' do
-        get 'scoped_pages/(:id)', :to => 'pages#show'
+      defaults id: "home" do
+        get "scoped_pages/(:id)", to: "pages#show"
       end
     end
 
-    get '/inline_pages'
-    assert_equal 'home', @request.params[:id]
+    get "/inline_pages"
+    assert_equal "home", @request.params[:id]
 
-    get '/default_pages'
-    assert_equal 'home', @request.params[:id]
+    get "/default_pages"
+    assert_equal "home", @request.params[:id]
 
-    get '/scoped_pages'
-    assert_equal 'home', @request.params[:id]
+    get "/scoped_pages"
+    assert_equal "home", @request.params[:id]
   end
 
   def test_default_integer_params
     draw do
-      get 'inline_pages/(:page)', to: 'pages#show', page: 1
-      get 'default_pages/(:page)', to: 'pages#show', defaults: { page: 1 }
+      get "inline_pages/(:page)", to: "pages#show", page: 1
+      get "default_pages/(:page)", to: "pages#show", defaults: { page: 1 }
 
       defaults page: 1 do
-        get 'scoped_pages/(:page)', to: 'pages#show'
+        get "scoped_pages/(:page)", to: "pages#show"
       end
     end
 
-    get '/inline_pages'
+    get "/inline_pages"
     assert_equal 1, @request.params[:page]
 
-    get '/default_pages'
+    get "/default_pages"
     assert_equal 1, @request.params[:page]
 
-    get '/scoped_pages'
+    get "/scoped_pages"
     assert_equal 1, @request.params[:page]
   end
 
+  def test_keyed_default_string_params_with_match
+    draw do
+      match "/", to: "pages#show", via: :get, defaults: { id: "home" }
+    end
+
+    get "/"
+    assert_equal "home", @request.params[:id]
+  end
+
+  def test_default_string_params_with_match
+    draw do
+      match "/", to: "pages#show", via: :get, id: "home"
+    end
+
+    get "/"
+    assert_equal "home", @request.params[:id]
+  end
+
+  def test_keyed_default_string_params_with_root
+    draw do
+      root to: "pages#show", defaults: { id: "home" }
+    end
+
+    get "/"
+    assert_equal "home", @request.params[:id]
+  end
+
+  def test_default_string_params_with_root
+    draw do
+      root to: "pages#show", id: "home"
+    end
+
+    get "/"
+    assert_equal "home", @request.params[:id]
+  end
+
   def test_resource_constraints
     draw do
-      resources :products, :constraints => { :id => /\d{4}/ } do
-        root :to => "products#root"
-        get :favorite, :on => :collection
+      resources :products, constraints: { id: /\d{4}/ } do
+        root to: "products#root"
+        get :favorite, on: :collection
         resources :images
       end
 
-      resource :dashboard, :constraints => { :ip => /192\.168\.1\.\d{1,3}/ }
+      resource :dashboard, constraints: { ip: /192\.168\.1\.\d{1,3}/ }
     end
 
-    get '/products/1'
-    assert_equal 'pass', @response.headers['X-Cascade']
-    get '/products'
-    assert_equal 'products#root', @response.body
-    get '/products/favorite'
-    assert_equal 'products#favorite', @response.body
-    get '/products/0001'
-    assert_equal 'products#show', @response.body
+    get "/products/1"
+    assert_equal "pass", @response.headers["X-Cascade"]
+    get "/products"
+    assert_equal "products#root", @response.body
+    get "/products/favorite"
+    assert_equal "products#favorite", @response.body
+    get "/products/0001"
+    assert_equal "products#show", @response.body
 
-    get '/products/1/images'
-    assert_equal 'pass', @response.headers['X-Cascade']
-    get '/products/0001/images'
-    assert_equal 'images#index', @response.body
-    get '/products/0001/images/0001'
-    assert_equal 'images#show', @response.body
+    get "/products/1/images"
+    assert_equal "pass", @response.headers["X-Cascade"]
+    get "/products/0001/images"
+    assert_equal "images#index", @response.body
+    get "/products/0001/images/0001"
+    assert_equal "images#show", @response.body
 
-    get '/dashboard', headers: { 'REMOTE_ADDR' => '10.0.0.100' }
-    assert_equal 'pass', @response.headers['X-Cascade']
-    get '/dashboard', headers: { 'REMOTE_ADDR' => '192.168.1.100' }
-    assert_equal 'dashboards#show', @response.body
+    get "/dashboard", headers: { "REMOTE_ADDR" => "10.0.0.100" }
+    assert_equal "pass", @response.headers["X-Cascade"]
+    get "/dashboard", headers: { "REMOTE_ADDR" => "192.168.1.100" }
+    assert_equal "dashboards#show", @response.body
   end
 
   def test_root_works_in_the_resources_scope
     draw do
       resources :products do
-        root :to => "products#root"
+        root to: "products#root"
       end
     end
 
-    get '/products'
-    assert_equal 'products#root', @response.body
-    assert_equal '/products', products_root_path
+    get "/products"
+    assert_equal "products#root", @response.body
+    assert_equal "/products", products_root_path
   end
 
   def test_module_scope
     draw do
-      resource :token, :module => :api
+      resource :token, module: :api
     end
 
-    get '/token'
-    assert_equal 'api/tokens#show', @response.body
-    assert_equal '/token', token_path
+    get "/token"
+    assert_equal "api/tokens#show", @response.body
+    assert_equal "/token", token_path
   end
 
   def test_path_scope
     draw do
-      scope :path => 'api' do
+      scope path: "api" do
         resource :me
-        get '/' => 'mes#index'
+        get "/" => "mes#index"
       end
     end
 
-    get '/api/me'
-    assert_equal 'mes#show', @response.body
-    assert_equal '/api/me', me_path
+    get "/api/me"
+    assert_equal "mes#show", @response.body
+    assert_equal "/api/me", me_path
 
-    get '/api'
-    assert_equal 'mes#index', @response.body
+    get "/api"
+    assert_equal "mes#index", @response.body
   end
 
   def test_symbol_scope
     draw do
-      scope :path => 'api' do
+      scope path: "api" do
         scope :v2 do
-          resource :me, as: 'v2_me'
-          get '/' => 'mes#index'
+          resource :me, as: "v2_me"
+          get "/" => "mes#index"
         end
 
         scope :v3, :admin do
-          resource :me, as: 'v3_me'
+          resource :me, as: "v3_me"
         end
       end
     end
 
-    get '/api/v2/me'
-    assert_equal 'mes#show', @response.body
-    assert_equal '/api/v2/me', v2_me_path
+    get "/api/v2/me"
+    assert_equal "mes#show", @response.body
+    assert_equal "/api/v2/me", v2_me_path
 
-    get '/api/v2'
-    assert_equal 'mes#index', @response.body
+    get "/api/v2"
+    assert_equal "mes#index", @response.body
 
-    get '/api/v3/admin/me'
-    assert_equal 'mes#show', @response.body
+    get "/api/v3/admin/me"
+    assert_equal "mes#show", @response.body
   end
 
   def test_url_generator_for_generic_route
@@ -1855,31 +1896,31 @@ class TestRoutingMapper < ActionDispatch::IntegrationTest
       end
     end
 
-    get '/whatever/foo/bar'
-    assert_equal 'foo#bar', @response.body
+    get "/whatever/foo/bar"
+    assert_equal "foo#bar", @response.body
 
-    assert_equal 'http://www.example.com/whatever/foo/bar/1',
-      url_for(:controller => "foo", :action => "bar", :id => 1)
+    assert_equal "http://www.example.com/whatever/foo/bar/1",
+      url_for(controller: "foo", action: "bar", id: 1)
   end
 
   def test_url_generator_for_namespaced_generic_route
     draw do
       ActiveSupport::Deprecation.silence do
-        get "whatever/:controller(/:action(/:id))", :id => /\d+/
+        get "whatever/:controller(/:action(/:id))", id: /\d+/
       end
     end
 
-    get '/whatever/foo/bar/show'
-    assert_equal 'foo/bar#show', @response.body
+    get "/whatever/foo/bar/show"
+    assert_equal "foo/bar#show", @response.body
 
-    get '/whatever/foo/bar/show/1'
-    assert_equal 'foo/bar#show', @response.body
+    get "/whatever/foo/bar/show/1"
+    assert_equal "foo/bar#show", @response.body
 
-    assert_equal 'http://www.example.com/whatever/foo/bar/show',
-      url_for(:controller => "foo/bar", :action => "show")
+    assert_equal "http://www.example.com/whatever/foo/bar/show",
+      url_for(controller: "foo/bar", action: "show")
 
-    assert_equal 'http://www.example.com/whatever/foo/bar/show/1',
-      url_for(:controller => "foo/bar", :action => "show", :id => '1')
+    assert_equal "http://www.example.com/whatever/foo/bar/show/1",
+      url_for(controller: "foo/bar", action: "show", id: "1")
   end
 
   def test_resource_new_actions
@@ -1890,16 +1931,16 @@ class TestRoutingMapper < ActionDispatch::IntegrationTest
         end
       end
 
-      scope 'pt', :as => 'pt' do
-        resources :projects, :path_names => { :new => 'novo' }, :path => 'projetos' do
-          post :preview, :on => :new
+      scope "pt", as: "pt" do
+        resources :projects, path_names: { new: "novo" }, path: "projetos" do
+          post :preview, on: :new
         end
 
-        resource  :admin, :path_names => { :new => 'novo' }, :path => 'administrador' do
-          post :preview, :on => :new
+        resource :admin, path_names: { new: "novo" }, path: "administrador" do
+          post :preview, on: :new
         end
 
-        resources :products, :path_names => { :new => 'novo' } do
+        resources :products, path_names: { new: "novo" } do
           new do
             post :preview
           end
@@ -1913,58 +1954,58 @@ class TestRoutingMapper < ActionDispatch::IntegrationTest
       end
     end
 
-    assert_equal '/replies/new/preview', preview_new_reply_path
-    assert_equal '/pt/projetos/novo/preview', preview_new_pt_project_path
-    assert_equal '/pt/administrador/novo/preview', preview_new_pt_admin_path
-    assert_equal '/pt/products/novo/preview', preview_new_pt_product_path
-    assert_equal '/profile/new/preview', preview_new_profile_path
+    assert_equal "/replies/new/preview", preview_new_reply_path
+    assert_equal "/pt/projetos/novo/preview", preview_new_pt_project_path
+    assert_equal "/pt/administrador/novo/preview", preview_new_pt_admin_path
+    assert_equal "/pt/products/novo/preview", preview_new_pt_product_path
+    assert_equal "/profile/new/preview", preview_new_profile_path
 
-    post '/replies/new/preview'
-    assert_equal 'replies#preview', @response.body
+    post "/replies/new/preview"
+    assert_equal "replies#preview", @response.body
 
-    post '/pt/projetos/novo/preview'
-    assert_equal 'projects#preview', @response.body
+    post "/pt/projetos/novo/preview"
+    assert_equal "projects#preview", @response.body
 
-    post '/pt/administrador/novo/preview'
-    assert_equal 'admins#preview', @response.body
+    post "/pt/administrador/novo/preview"
+    assert_equal "admins#preview", @response.body
 
-    post '/pt/products/novo/preview'
-    assert_equal 'products#preview', @response.body
+    post "/pt/products/novo/preview"
+    assert_equal "products#preview", @response.body
 
-    post '/profile/new/preview'
-    assert_equal 'profiles#preview', @response.body
+    post "/profile/new/preview"
+    assert_equal "profiles#preview", @response.body
   end
 
   def test_resource_merges_options_from_scope
     draw do
-      scope :only => :show do
+      scope only: :show do
         resource :account
       end
     end
 
     assert_raise(NoMethodError) { new_account_path }
 
-    get '/account/new'
+    get "/account/new"
     assert_equal 404, status
   end
 
   def test_resources_merges_options_from_scope
     draw do
-      scope :only => [:index, :show] do
+      scope only: [:index, :show] do
         resources :products do
           resources :images
         end
       end
     end
 
-    assert_raise(NoMethodError) { edit_product_path('1') }
+    assert_raise(NoMethodError) { edit_product_path("1") }
 
-    get '/products/1/edit'
+    get "/products/1/edit"
     assert_equal 404, status
 
-    assert_raise(NoMethodError) { edit_product_image_path('1', '2') }
+    assert_raise(NoMethodError) { edit_product_image_path("1", "2") }
 
-    post '/products/1/images/2/edit'
+    post "/products/1/images/2/edit"
     assert_equal 404, status
   end
 
@@ -1979,7 +2020,7 @@ class TestRoutingMapper < ActionDispatch::IntegrationTest
         end
       end
 
-      resources :threads, :shallow => true do
+      resources :threads, shallow: true do
         resource :owner
         resources :messages do
           resources :comments do
@@ -1991,105 +2032,105 @@ class TestRoutingMapper < ActionDispatch::IntegrationTest
       end
     end
 
-    get '/api/teams'
-    assert_equal 'api/teams#index', @response.body
-    assert_equal '/api/teams', api_teams_path
+    get "/api/teams"
+    assert_equal "api/teams#index", @response.body
+    assert_equal "/api/teams", api_teams_path
 
-    get '/api/teams/new'
-    assert_equal 'api/teams#new', @response.body
-    assert_equal '/api/teams/new', new_api_team_path
+    get "/api/teams/new"
+    assert_equal "api/teams#new", @response.body
+    assert_equal "/api/teams/new", new_api_team_path
 
-    get '/api/teams/1'
-    assert_equal 'api/teams#show', @response.body
-    assert_equal '/api/teams/1', api_team_path(:id => '1')
+    get "/api/teams/1"
+    assert_equal "api/teams#show", @response.body
+    assert_equal "/api/teams/1", api_team_path(id: "1")
 
-    get '/api/teams/1/edit'
-    assert_equal 'api/teams#edit', @response.body
-    assert_equal '/api/teams/1/edit', edit_api_team_path(:id => '1')
+    get "/api/teams/1/edit"
+    assert_equal "api/teams#edit", @response.body
+    assert_equal "/api/teams/1/edit", edit_api_team_path(id: "1")
 
-    get '/api/teams/1/players'
-    assert_equal 'api/players#index', @response.body
-    assert_equal '/api/teams/1/players', api_team_players_path(:team_id => '1')
+    get "/api/teams/1/players"
+    assert_equal "api/players#index", @response.body
+    assert_equal "/api/teams/1/players", api_team_players_path(team_id: "1")
 
-    get '/api/teams/1/players/new'
-    assert_equal 'api/players#new', @response.body
-    assert_equal '/api/teams/1/players/new', new_api_team_player_path(:team_id => '1')
+    get "/api/teams/1/players/new"
+    assert_equal "api/players#new", @response.body
+    assert_equal "/api/teams/1/players/new", new_api_team_player_path(team_id: "1")
 
-    get '/api/players/2'
-    assert_equal 'api/players#show', @response.body
-    assert_equal '/api/players/2', api_player_path(:id => '2')
+    get "/api/players/2"
+    assert_equal "api/players#show", @response.body
+    assert_equal "/api/players/2", api_player_path(id: "2")
 
-    get '/api/players/2/edit'
-    assert_equal 'api/players#edit', @response.body
-    assert_equal '/api/players/2/edit', edit_api_player_path(:id => '2')
+    get "/api/players/2/edit"
+    assert_equal "api/players#edit", @response.body
+    assert_equal "/api/players/2/edit", edit_api_player_path(id: "2")
 
-    get '/api/teams/1/captain'
-    assert_equal 'api/captains#show', @response.body
-    assert_equal '/api/teams/1/captain', api_team_captain_path(:team_id => '1')
+    get "/api/teams/1/captain"
+    assert_equal "api/captains#show", @response.body
+    assert_equal "/api/teams/1/captain", api_team_captain_path(team_id: "1")
 
-    get '/api/teams/1/captain/new'
-    assert_equal 'api/captains#new', @response.body
-    assert_equal '/api/teams/1/captain/new', new_api_team_captain_path(:team_id => '1')
+    get "/api/teams/1/captain/new"
+    assert_equal "api/captains#new", @response.body
+    assert_equal "/api/teams/1/captain/new", new_api_team_captain_path(team_id: "1")
 
-    get '/api/teams/1/captain/edit'
-    assert_equal 'api/captains#edit', @response.body
-    assert_equal '/api/teams/1/captain/edit', edit_api_team_captain_path(:team_id => '1')
+    get "/api/teams/1/captain/edit"
+    assert_equal "api/captains#edit", @response.body
+    assert_equal "/api/teams/1/captain/edit", edit_api_team_captain_path(team_id: "1")
 
-    get '/threads'
-    assert_equal 'threads#index', @response.body
-    assert_equal '/threads', threads_path
+    get "/threads"
+    assert_equal "threads#index", @response.body
+    assert_equal "/threads", threads_path
 
-    get '/threads/new'
-    assert_equal 'threads#new', @response.body
-    assert_equal '/threads/new', new_thread_path
+    get "/threads/new"
+    assert_equal "threads#new", @response.body
+    assert_equal "/threads/new", new_thread_path
 
-    get '/threads/1'
-    assert_equal 'threads#show', @response.body
-    assert_equal '/threads/1', thread_path(:id => '1')
+    get "/threads/1"
+    assert_equal "threads#show", @response.body
+    assert_equal "/threads/1", thread_path(id: "1")
 
-    get '/threads/1/edit'
-    assert_equal 'threads#edit', @response.body
-    assert_equal '/threads/1/edit', edit_thread_path(:id => '1')
+    get "/threads/1/edit"
+    assert_equal "threads#edit", @response.body
+    assert_equal "/threads/1/edit", edit_thread_path(id: "1")
 
-    get '/threads/1/owner'
-    assert_equal 'owners#show', @response.body
-    assert_equal '/threads/1/owner', thread_owner_path(:thread_id => '1')
+    get "/threads/1/owner"
+    assert_equal "owners#show", @response.body
+    assert_equal "/threads/1/owner", thread_owner_path(thread_id: "1")
 
-    get '/threads/1/messages'
-    assert_equal 'messages#index', @response.body
-    assert_equal '/threads/1/messages', thread_messages_path(:thread_id => '1')
+    get "/threads/1/messages"
+    assert_equal "messages#index", @response.body
+    assert_equal "/threads/1/messages", thread_messages_path(thread_id: "1")
 
-    get '/threads/1/messages/new'
-    assert_equal 'messages#new', @response.body
-    assert_equal '/threads/1/messages/new', new_thread_message_path(:thread_id => '1')
+    get "/threads/1/messages/new"
+    assert_equal "messages#new", @response.body
+    assert_equal "/threads/1/messages/new", new_thread_message_path(thread_id: "1")
 
-    get '/messages/2'
-    assert_equal 'messages#show', @response.body
-    assert_equal '/messages/2', message_path(:id => '2')
+    get "/messages/2"
+    assert_equal "messages#show", @response.body
+    assert_equal "/messages/2", message_path(id: "2")
 
-    get '/messages/2/edit'
-    assert_equal 'messages#edit', @response.body
-    assert_equal '/messages/2/edit', edit_message_path(:id => '2')
+    get "/messages/2/edit"
+    assert_equal "messages#edit", @response.body
+    assert_equal "/messages/2/edit", edit_message_path(id: "2")
 
-    get '/messages/2/comments'
-    assert_equal 'comments#index', @response.body
-    assert_equal '/messages/2/comments', message_comments_path(:message_id => '2')
+    get "/messages/2/comments"
+    assert_equal "comments#index", @response.body
+    assert_equal "/messages/2/comments", message_comments_path(message_id: "2")
 
-    get '/messages/2/comments/new'
-    assert_equal 'comments#new', @response.body
-    assert_equal '/messages/2/comments/new', new_message_comment_path(:message_id => '2')
+    get "/messages/2/comments/new"
+    assert_equal "comments#new", @response.body
+    assert_equal "/messages/2/comments/new", new_message_comment_path(message_id: "2")
 
-    get '/comments/3'
-    assert_equal 'comments#show', @response.body
-    assert_equal '/comments/3', comment_path(:id => '3')
+    get "/comments/3"
+    assert_equal "comments#show", @response.body
+    assert_equal "/comments/3", comment_path(id: "3")
 
-    get '/comments/3/edit'
-    assert_equal 'comments#edit', @response.body
-    assert_equal '/comments/3/edit', edit_comment_path(:id => '3')
+    get "/comments/3/edit"
+    assert_equal "comments#edit", @response.body
+    assert_equal "/comments/3/edit", edit_comment_path(id: "3")
 
-    post '/comments/3/preview'
-    assert_equal 'comments#preview', @response.body
-    assert_equal '/comments/3/preview', preview_comment_path(:id => '3')
+    post "/comments/3/preview"
+    assert_equal "comments#preview", @response.body
+    assert_equal "/comments/3/preview", preview_comment_path(id: "3")
   end
 
   def test_shallow_nested_resources_inside_resource
@@ -2099,33 +2140,33 @@ class TestRoutingMapper < ActionDispatch::IntegrationTest
       end
     end
 
-    get '/membership/cards'
-    assert_equal 'cards#index', @response.body
-    assert_equal '/membership/cards', membership_cards_path
+    get "/membership/cards"
+    assert_equal "cards#index", @response.body
+    assert_equal "/membership/cards", membership_cards_path
 
-    get '/membership/cards/new'
-    assert_equal 'cards#new', @response.body
-    assert_equal '/membership/cards/new', new_membership_card_path
+    get "/membership/cards/new"
+    assert_equal "cards#new", @response.body
+    assert_equal "/membership/cards/new", new_membership_card_path
 
-    post '/membership/cards'
-    assert_equal 'cards#create', @response.body
+    post "/membership/cards"
+    assert_equal "cards#create", @response.body
 
-    get '/cards/1'
-    assert_equal 'cards#show', @response.body
-    assert_equal '/cards/1', card_path('1')
+    get "/cards/1"
+    assert_equal "cards#show", @response.body
+    assert_equal "/cards/1", card_path("1")
 
-    get '/cards/1/edit'
-    assert_equal 'cards#edit', @response.body
-    assert_equal '/cards/1/edit', edit_card_path('1')
+    get "/cards/1/edit"
+    assert_equal "cards#edit", @response.body
+    assert_equal "/cards/1/edit", edit_card_path("1")
 
-    put '/cards/1'
-    assert_equal 'cards#update', @response.body
+    put "/cards/1"
+    assert_equal "cards#update", @response.body
 
-    patch '/cards/1'
-    assert_equal 'cards#update', @response.body
+    patch "/cards/1"
+    assert_equal "cards#update", @response.body
 
-    delete '/cards/1'
-    assert_equal 'cards#destroy', @response.body
+    delete "/cards/1"
+    assert_equal "cards#destroy", @response.body
   end
 
   def test_shallow_deeply_nested_resources
@@ -2137,13 +2178,13 @@ class TestRoutingMapper < ActionDispatch::IntegrationTest
       end
     end
 
-    get '/comments/1'
-    assert_equal 'comments#show', @response.body
+    get "/comments/1"
+    assert_equal "comments#show", @response.body
 
-    assert_equal '/comments/1', comment_path('1')
-    assert_equal '/blogs/new', new_blog_path
-    assert_equal '/blogs/1/posts/new', new_blog_post_path(:blog_id => 1)
-    assert_equal '/blogs/1/posts/2/comments/new', new_blog_post_comment_path(:blog_id => 1, :post_id => 2)
+    assert_equal "/comments/1", comment_path("1")
+    assert_equal "/blogs/new", new_blog_path
+    assert_equal "/blogs/1/posts/new", new_blog_post_path(blog_id: 1)
+    assert_equal "/blogs/1/posts/2/comments/new", new_blog_post_comment_path(blog_id: 1, post_id: 2)
   end
 
   def test_direct_children_of_shallow_resources
@@ -2155,22 +2196,22 @@ class TestRoutingMapper < ActionDispatch::IntegrationTest
       end
     end
 
-    post '/posts/1/comments'
-    assert_equal 'comments#create', @response.body
-    assert_equal '/posts/1/comments', post_comments_path('1')
+    post "/posts/1/comments"
+    assert_equal "comments#create", @response.body
+    assert_equal "/posts/1/comments", post_comments_path("1")
 
-    get '/posts/2/comments/new'
-    assert_equal 'comments#new', @response.body
-    assert_equal '/posts/2/comments/new', new_post_comment_path('2')
+    get "/posts/2/comments/new"
+    assert_equal "comments#new", @response.body
+    assert_equal "/posts/2/comments/new", new_post_comment_path("2")
 
-    get '/posts/1/comments'
-    assert_equal 'comments#index', @response.body
-    assert_equal '/posts/1/comments', post_comments_path('1')
+    get "/posts/1/comments"
+    assert_equal "comments#index", @response.body
+    assert_equal "/posts/1/comments", post_comments_path("1")
   end
 
   def test_shallow_nested_resources_within_scope
     draw do
-      scope '/hello' do
+      scope "/hello" do
         shallow do
           resources :notes do
             resources :trackbacks
@@ -2179,120 +2220,120 @@ class TestRoutingMapper < ActionDispatch::IntegrationTest
       end
     end
 
-    get '/hello/notes/1/trackbacks'
-    assert_equal 'trackbacks#index', @response.body
-    assert_equal '/hello/notes/1/trackbacks', note_trackbacks_path(:note_id => 1)
+    get "/hello/notes/1/trackbacks"
+    assert_equal "trackbacks#index", @response.body
+    assert_equal "/hello/notes/1/trackbacks", note_trackbacks_path(note_id: 1)
 
-    get '/hello/notes/1/edit'
-    assert_equal 'notes#edit', @response.body
-    assert_equal '/hello/notes/1/edit', edit_note_path(:id => '1')
+    get "/hello/notes/1/edit"
+    assert_equal "notes#edit", @response.body
+    assert_equal "/hello/notes/1/edit", edit_note_path(id: "1")
 
-    get '/hello/notes/1/trackbacks/new'
-    assert_equal 'trackbacks#new', @response.body
-    assert_equal '/hello/notes/1/trackbacks/new', new_note_trackback_path(:note_id => 1)
+    get "/hello/notes/1/trackbacks/new"
+    assert_equal "trackbacks#new", @response.body
+    assert_equal "/hello/notes/1/trackbacks/new", new_note_trackback_path(note_id: 1)
 
-    get '/hello/trackbacks/1'
-    assert_equal 'trackbacks#show', @response.body
-    assert_equal '/hello/trackbacks/1', trackback_path(:id => '1')
+    get "/hello/trackbacks/1"
+    assert_equal "trackbacks#show", @response.body
+    assert_equal "/hello/trackbacks/1", trackback_path(id: "1")
 
-    get '/hello/trackbacks/1/edit'
-    assert_equal 'trackbacks#edit', @response.body
-    assert_equal '/hello/trackbacks/1/edit', edit_trackback_path(:id => '1')
+    get "/hello/trackbacks/1/edit"
+    assert_equal "trackbacks#edit", @response.body
+    assert_equal "/hello/trackbacks/1/edit", edit_trackback_path(id: "1")
 
-    put '/hello/trackbacks/1'
-    assert_equal 'trackbacks#update', @response.body
+    put "/hello/trackbacks/1"
+    assert_equal "trackbacks#update", @response.body
 
-    post '/hello/notes/1/trackbacks'
-    assert_equal 'trackbacks#create', @response.body
+    post "/hello/notes/1/trackbacks"
+    assert_equal "trackbacks#create", @response.body
 
-    delete '/hello/trackbacks/1'
-    assert_equal 'trackbacks#destroy', @response.body
+    delete "/hello/trackbacks/1"
+    assert_equal "trackbacks#destroy", @response.body
 
-    get '/hello/notes'
-    assert_equal 'notes#index', @response.body
+    get "/hello/notes"
+    assert_equal "notes#index", @response.body
 
-    post '/hello/notes'
-    assert_equal 'notes#create', @response.body
+    post "/hello/notes"
+    assert_equal "notes#create", @response.body
 
-    get '/hello/notes/new'
-    assert_equal 'notes#new', @response.body
-    assert_equal '/hello/notes/new', new_note_path
+    get "/hello/notes/new"
+    assert_equal "notes#new", @response.body
+    assert_equal "/hello/notes/new", new_note_path
 
-    get '/hello/notes/1'
-    assert_equal 'notes#show', @response.body
-    assert_equal '/hello/notes/1', note_path(:id => 1)
+    get "/hello/notes/1"
+    assert_equal "notes#show", @response.body
+    assert_equal "/hello/notes/1", note_path(id: 1)
 
-    put '/hello/notes/1'
-    assert_equal 'notes#update', @response.body
+    put "/hello/notes/1"
+    assert_equal "notes#update", @response.body
 
-    delete '/hello/notes/1'
-    assert_equal 'notes#destroy', @response.body
+    delete "/hello/notes/1"
+    assert_equal "notes#destroy", @response.body
   end
 
   def test_shallow_option_nested_resources_within_scope
     draw do
-      scope '/hello' do
-        resources :notes, :shallow => true do
+      scope "/hello" do
+        resources :notes, shallow: true do
           resources :trackbacks
         end
       end
     end
 
-    get '/hello/notes/1/trackbacks'
-    assert_equal 'trackbacks#index', @response.body
-    assert_equal '/hello/notes/1/trackbacks', note_trackbacks_path(:note_id => 1)
+    get "/hello/notes/1/trackbacks"
+    assert_equal "trackbacks#index", @response.body
+    assert_equal "/hello/notes/1/trackbacks", note_trackbacks_path(note_id: 1)
 
-    get '/hello/notes/1/edit'
-    assert_equal 'notes#edit', @response.body
-    assert_equal '/hello/notes/1/edit', edit_note_path(:id => '1')
+    get "/hello/notes/1/edit"
+    assert_equal "notes#edit", @response.body
+    assert_equal "/hello/notes/1/edit", edit_note_path(id: "1")
 
-    get '/hello/notes/1/trackbacks/new'
-    assert_equal 'trackbacks#new', @response.body
-    assert_equal '/hello/notes/1/trackbacks/new', new_note_trackback_path(:note_id => 1)
+    get "/hello/notes/1/trackbacks/new"
+    assert_equal "trackbacks#new", @response.body
+    assert_equal "/hello/notes/1/trackbacks/new", new_note_trackback_path(note_id: 1)
 
-    get '/hello/trackbacks/1'
-    assert_equal 'trackbacks#show', @response.body
-    assert_equal '/hello/trackbacks/1', trackback_path(:id => '1')
+    get "/hello/trackbacks/1"
+    assert_equal "trackbacks#show", @response.body
+    assert_equal "/hello/trackbacks/1", trackback_path(id: "1")
 
-    get '/hello/trackbacks/1/edit'
-    assert_equal 'trackbacks#edit', @response.body
-    assert_equal '/hello/trackbacks/1/edit', edit_trackback_path(:id => '1')
+    get "/hello/trackbacks/1/edit"
+    assert_equal "trackbacks#edit", @response.body
+    assert_equal "/hello/trackbacks/1/edit", edit_trackback_path(id: "1")
 
-    put '/hello/trackbacks/1'
-    assert_equal 'trackbacks#update', @response.body
+    put "/hello/trackbacks/1"
+    assert_equal "trackbacks#update", @response.body
 
-    post '/hello/notes/1/trackbacks'
-    assert_equal 'trackbacks#create', @response.body
+    post "/hello/notes/1/trackbacks"
+    assert_equal "trackbacks#create", @response.body
 
-    delete '/hello/trackbacks/1'
-    assert_equal 'trackbacks#destroy', @response.body
+    delete "/hello/trackbacks/1"
+    assert_equal "trackbacks#destroy", @response.body
 
-    get '/hello/notes'
-    assert_equal 'notes#index', @response.body
+    get "/hello/notes"
+    assert_equal "notes#index", @response.body
 
-    post '/hello/notes'
-    assert_equal 'notes#create', @response.body
+    post "/hello/notes"
+    assert_equal "notes#create", @response.body
 
-    get '/hello/notes/new'
-    assert_equal 'notes#new', @response.body
-    assert_equal '/hello/notes/new', new_note_path
+    get "/hello/notes/new"
+    assert_equal "notes#new", @response.body
+    assert_equal "/hello/notes/new", new_note_path
 
-    get '/hello/notes/1'
-    assert_equal 'notes#show', @response.body
-    assert_equal '/hello/notes/1', note_path(:id => 1)
+    get "/hello/notes/1"
+    assert_equal "notes#show", @response.body
+    assert_equal "/hello/notes/1", note_path(id: 1)
 
-    put '/hello/notes/1'
-    assert_equal 'notes#update', @response.body
+    put "/hello/notes/1"
+    assert_equal "notes#update", @response.body
 
-    delete '/hello/notes/1'
-    assert_equal 'notes#destroy', @response.body
+    delete "/hello/notes/1"
+    assert_equal "notes#destroy", @response.body
   end
 
   def test_custom_resource_routes_are_scoped
     draw do
       resources :customers do
-        get :recent, :on => :collection
-        get "profile", :on => :member
+        get :recent, on: :collection
+        get "profile", on: :member
         get "secret/profile" => "customers#secret", :on => :member
         post "preview" => "customers#preview", :as => :another_preview, :on => :new
         resource :avatar do
@@ -2300,11 +2341,11 @@ class TestRoutingMapper < ActionDispatch::IntegrationTest
         end
         resources :invoices do
           get "outstanding" => "invoices#outstanding", :on => :collection
-          get "overdue", :action => :overdue, :on => :collection
+          get "overdue", action: :overdue, on: :collection
           get "print" => "invoices#print", :as => :print, :on => :member
           post "preview" => "invoices#preview", :as => :preview, :on => :new
         end
-        resources :notes, :shallow => true do
+        resources :notes, shallow: true do
           get "preview" => "notes#preview", :as => :preview, :on => :new
           get "print" => "notes#print", :as => :print, :on => :member
         end
@@ -2319,79 +2360,79 @@ class TestRoutingMapper < ActionDispatch::IntegrationTest
       end
     end
 
-    assert_equal '/customers/recent', recent_customers_path
-    assert_equal '/customers/1/profile', profile_customer_path(:id => '1')
-    assert_equal '/customers/1/secret/profile', secret_profile_customer_path(:id => '1')
-    assert_equal '/customers/new/preview', another_preview_new_customer_path
-    assert_equal '/customers/1/avatar/thumbnail.jpg', thumbnail_customer_avatar_path(:customer_id => '1', :format => :jpg)
-    assert_equal '/customers/1/invoices/outstanding', outstanding_customer_invoices_path(:customer_id => '1')
-    assert_equal '/customers/1/invoices/2/print', print_customer_invoice_path(:customer_id => '1', :id => '2')
-    assert_equal '/customers/1/invoices/new/preview', preview_new_customer_invoice_path(:customer_id => '1')
-    assert_equal '/customers/1/notes/new/preview', preview_new_customer_note_path(:customer_id => '1')
-    assert_equal '/notes/1/print', print_note_path(:id => '1')
-    assert_equal '/api/customers/recent', recent_api_customers_path
-    assert_equal '/api/customers/1/profile', profile_api_customer_path(:id => '1')
-    assert_equal '/api/customers/new/preview', preview_new_api_customer_path
+    assert_equal "/customers/recent", recent_customers_path
+    assert_equal "/customers/1/profile", profile_customer_path(id: "1")
+    assert_equal "/customers/1/secret/profile", secret_profile_customer_path(id: "1")
+    assert_equal "/customers/new/preview", another_preview_new_customer_path
+    assert_equal "/customers/1/avatar/thumbnail.jpg", thumbnail_customer_avatar_path(customer_id: "1", format: :jpg)
+    assert_equal "/customers/1/invoices/outstanding", outstanding_customer_invoices_path(customer_id: "1")
+    assert_equal "/customers/1/invoices/2/print", print_customer_invoice_path(customer_id: "1", id: "2")
+    assert_equal "/customers/1/invoices/new/preview", preview_new_customer_invoice_path(customer_id: "1")
+    assert_equal "/customers/1/notes/new/preview", preview_new_customer_note_path(customer_id: "1")
+    assert_equal "/notes/1/print", print_note_path(id: "1")
+    assert_equal "/api/customers/recent", recent_api_customers_path
+    assert_equal "/api/customers/1/profile", profile_api_customer_path(id: "1")
+    assert_equal "/api/customers/new/preview", preview_new_api_customer_path
 
-    get '/customers/1/invoices/overdue'
-    assert_equal 'invoices#overdue', @response.body
+    get "/customers/1/invoices/overdue"
+    assert_equal "invoices#overdue", @response.body
 
-    get '/customers/1/secret/profile'
-    assert_equal 'customers#secret', @response.body
+    get "/customers/1/secret/profile"
+    assert_equal "customers#secret", @response.body
   end
 
   def test_shallow_nested_routes_ignore_module
     draw do
-      scope :module => :api do
-        resources :errors, :shallow => true do
+      scope module: :api do
+        resources :errors, shallow: true do
           resources :notices
         end
       end
     end
 
-    get '/errors/1/notices'
-    assert_equal 'api/notices#index', @response.body
-    assert_equal '/errors/1/notices', error_notices_path(:error_id => '1')
+    get "/errors/1/notices"
+    assert_equal "api/notices#index", @response.body
+    assert_equal "/errors/1/notices", error_notices_path(error_id: "1")
 
-    get '/notices/1'
-    assert_equal 'api/notices#show', @response.body
-    assert_equal '/notices/1', notice_path(:id => '1')
+    get "/notices/1"
+    assert_equal "api/notices#show", @response.body
+    assert_equal "/notices/1", notice_path(id: "1")
   end
 
   def test_non_greedy_regexp
     draw do
       namespace :api do
-        scope(':version', :version => /.+/) do
-          resources :users, :id => /.+?/, :format => /json|xml/
+        scope(":version", version: /.+/) do
+          resources :users, id: /.+?/, format: /json|xml/
         end
       end
     end
 
-    get '/api/1.0/users'
-    assert_equal 'api/users#index', @response.body
-    assert_equal '/api/1.0/users', api_users_path(:version => '1.0')
+    get "/api/1.0/users"
+    assert_equal "api/users#index", @response.body
+    assert_equal "/api/1.0/users", api_users_path(version: "1.0")
 
-    get '/api/1.0/users.json'
-    assert_equal 'api/users#index', @response.body
+    get "/api/1.0/users.json"
+    assert_equal "api/users#index", @response.body
     assert_equal true, @request.format.json?
-    assert_equal '/api/1.0/users.json', api_users_path(:version => '1.0', :format => :json)
+    assert_equal "/api/1.0/users.json", api_users_path(version: "1.0", format: :json)
 
-    get '/api/1.0/users/first.last'
-    assert_equal 'api/users#show', @response.body
-    assert_equal 'first.last', @request.params[:id]
-    assert_equal '/api/1.0/users/first.last', api_user_path(:version => '1.0', :id => 'first.last')
+    get "/api/1.0/users/first.last"
+    assert_equal "api/users#show", @response.body
+    assert_equal "first.last", @request.params[:id]
+    assert_equal "/api/1.0/users/first.last", api_user_path(version: "1.0", id: "first.last")
 
-    get '/api/1.0/users/first.last.xml'
-    assert_equal 'api/users#show', @response.body
-    assert_equal 'first.last', @request.params[:id]
+    get "/api/1.0/users/first.last.xml"
+    assert_equal "api/users#show", @response.body
+    assert_equal "first.last", @request.params[:id]
     assert_equal true, @request.format.xml?
-    assert_equal '/api/1.0/users/first.last.xml', api_user_path(:version => '1.0', :id => 'first.last', :format => :xml)
+    assert_equal "/api/1.0/users/first.last.xml", api_user_path(version: "1.0", id: "first.last", format: :xml)
   end
 
   def test_match_without_via
     assert_raises(ArgumentError) do
       draw do
-        match '/foo/bar', :to => 'files#show'
+        match "/foo/bar", to: "files#show"
       end
     end
   end
@@ -2399,17 +2440,17 @@ class TestRoutingMapper < ActionDispatch::IntegrationTest
   def test_match_with_empty_via
     assert_raises(ArgumentError) do
       draw do
-        match '/foo/bar', :to => 'files#show', :via => []
+        match "/foo/bar", to: "files#show", via: []
       end
     end
   end
 
   def test_glob_parameter_accepts_regexp
     draw do
-      get '/:locale/*file.:format', :to => 'files#show', :file => /path\/to\/existing\/file/
+      get "/:locale/*file.:format", to: "files#show", file: /path\/to\/existing\/file/
     end
 
-    get '/en/path/to/existing/file.html'
+    get "/en/path/to/existing/file.html"
     assert_equal 200, @response.status
   end
 
@@ -2418,8 +2459,8 @@ class TestRoutingMapper < ActionDispatch::IntegrationTest
       resources :content
     end
 
-    get '/content'
-    assert_equal 'content#index', @response.body
+    get "/content"
+    assert_equal "content#index", @response.body
   end
 
   def test_url_generator_for_optional_prefix_dynamic_segment
@@ -2427,15 +2468,15 @@ class TestRoutingMapper < ActionDispatch::IntegrationTest
       get "(/:username)/followers" => "followers#index"
     end
 
-    get '/bob/followers'
-    assert_equal 'followers#index', @response.body
-    assert_equal 'http://www.example.com/bob/followers',
-      url_for(:controller => "followers", :action => "index", :username => "bob")
+    get "/bob/followers"
+    assert_equal "followers#index", @response.body
+    assert_equal "http://www.example.com/bob/followers",
+      url_for(controller: "followers", action: "index", username: "bob")
 
-    get '/followers'
-    assert_equal 'followers#index', @response.body
-    assert_equal 'http://www.example.com/followers',
-      url_for(:controller => "followers", :action => "index", :username => nil)
+    get "/followers"
+    assert_equal "followers#index", @response.body
+    assert_equal "http://www.example.com/followers",
+      url_for(controller: "followers", action: "index", username: nil)
   end
 
   def test_url_generator_for_optional_suffix_static_and_dynamic_segment
@@ -2443,15 +2484,15 @@ class TestRoutingMapper < ActionDispatch::IntegrationTest
       get "/groups(/user/:username)" => "groups#index"
     end
 
-    get '/groups/user/bob'
-    assert_equal 'groups#index', @response.body
-    assert_equal 'http://www.example.com/groups/user/bob',
-      url_for(:controller => "groups", :action => "index", :username => "bob")
+    get "/groups/user/bob"
+    assert_equal "groups#index", @response.body
+    assert_equal "http://www.example.com/groups/user/bob",
+      url_for(controller: "groups", action: "index", username: "bob")
 
-    get '/groups'
-    assert_equal 'groups#index', @response.body
-    assert_equal 'http://www.example.com/groups',
-      url_for(:controller => "groups", :action => "index", :username => nil)
+    get "/groups"
+    assert_equal "groups#index", @response.body
+    assert_equal "http://www.example.com/groups",
+      url_for(controller: "groups", action: "index", username: nil)
   end
 
   def test_url_generator_for_optional_prefix_static_and_dynamic_segment
@@ -2459,66 +2500,66 @@ class TestRoutingMapper < ActionDispatch::IntegrationTest
       get "(/user/:username)/photos" => "photos#index"
     end
 
-    get '/user/bob/photos'
-    assert_equal 'photos#index', @response.body
-    assert_equal 'http://www.example.com/user/bob/photos',
-      url_for(:controller => "photos", :action => "index", :username => "bob")
+    get "/user/bob/photos"
+    assert_equal "photos#index", @response.body
+    assert_equal "http://www.example.com/user/bob/photos",
+      url_for(controller: "photos", action: "index", username: "bob")
 
-    get '/photos'
-    assert_equal 'photos#index', @response.body
-    assert_equal 'http://www.example.com/photos',
-      url_for(:controller => "photos", :action => "index", :username => nil)
+    get "/photos"
+    assert_equal "photos#index", @response.body
+    assert_equal "http://www.example.com/photos",
+      url_for(controller: "photos", action: "index", username: nil)
   end
 
   def test_url_recognition_for_optional_static_segments
     draw do
-      scope '(groups)' do
-        scope '(discussions)' do
+      scope "(groups)" do
+        scope "(discussions)" do
           resources :messages
         end
       end
     end
 
-    get '/groups/discussions/messages'
-    assert_equal 'messages#index', @response.body
+    get "/groups/discussions/messages"
+    assert_equal "messages#index", @response.body
 
-    get '/groups/discussions/messages/1'
-    assert_equal 'messages#show', @response.body
+    get "/groups/discussions/messages/1"
+    assert_equal "messages#show", @response.body
 
-    get '/groups/messages'
-    assert_equal 'messages#index', @response.body
+    get "/groups/messages"
+    assert_equal "messages#index", @response.body
 
-    get '/groups/messages/1'
-    assert_equal 'messages#show', @response.body
+    get "/groups/messages/1"
+    assert_equal "messages#show", @response.body
 
-    get '/discussions/messages'
-    assert_equal 'messages#index', @response.body
+    get "/discussions/messages"
+    assert_equal "messages#index", @response.body
 
-    get '/discussions/messages/1'
-    assert_equal 'messages#show', @response.body
+    get "/discussions/messages/1"
+    assert_equal "messages#show", @response.body
 
-    get '/messages'
-    assert_equal 'messages#index', @response.body
+    get "/messages"
+    assert_equal "messages#index", @response.body
 
-    get '/messages/1'
-    assert_equal 'messages#show', @response.body
+    get "/messages/1"
+    assert_equal "messages#show", @response.body
   end
 
   def test_router_removes_invalid_conditions
     draw do
-      scope :constraints => { :id => /\d+/ } do
-        get '/tickets', :to => 'tickets#index', :as => :tickets
+      scope constraints: { id: /\d+/ } do
+        get "/tickets", to: "tickets#index", as: :tickets
       end
     end
 
-    get '/tickets'
-    assert_equal 'tickets#index', @response.body
-    assert_equal '/tickets', tickets_path
+    get "/tickets"
+    assert_equal "tickets#index", @response.body
+    assert_equal "/tickets", tickets_path
   end
 
   def test_constraints_are_merged_from_scope
     draw do
-      scope :constraints => { :id => /\d{4}/ } do
+      scope constraints: { id: /\d{4}/ } do
         resources :movies do
           resources :reviews
           resource :trailer
@@ -2526,42 +2567,42 @@ class TestRoutingMapper < ActionDispatch::IntegrationTest
       end
     end
 
-    get '/movies/0001'
-    assert_equal 'movies#show', @response.body
-    assert_equal '/movies/0001', movie_path(:id => '0001')
+    get "/movies/0001"
+    assert_equal "movies#show", @response.body
+    assert_equal "/movies/0001", movie_path(id: "0001")
 
-    get '/movies/00001'
-    assert_equal 'Not Found', @response.body
-    assert_raises(ActionController::UrlGenerationError){ movie_path(:id => '00001') }
+    get "/movies/00001"
+    assert_equal "Not Found", @response.body
+    assert_raises(ActionController::UrlGenerationError) { movie_path(id: "00001") }
 
-    get '/movies/0001/reviews'
-    assert_equal 'reviews#index', @response.body
-    assert_equal '/movies/0001/reviews', movie_reviews_path(:movie_id => '0001')
+    get "/movies/0001/reviews"
+    assert_equal "reviews#index", @response.body
+    assert_equal "/movies/0001/reviews", movie_reviews_path(movie_id: "0001")
 
-    get '/movies/00001/reviews'
-    assert_equal 'Not Found', @response.body
-    assert_raises(ActionController::UrlGenerationError){ movie_reviews_path(:movie_id => '00001') }
+    get "/movies/00001/reviews"
+    assert_equal "Not Found", @response.body
+    assert_raises(ActionController::UrlGenerationError) { movie_reviews_path(movie_id: "00001") }
 
-    get '/movies/0001/reviews/0001'
-    assert_equal 'reviews#show', @response.body
-    assert_equal '/movies/0001/reviews/0001', movie_review_path(:movie_id => '0001', :id => '0001')
+    get "/movies/0001/reviews/0001"
+    assert_equal "reviews#show", @response.body
+    assert_equal "/movies/0001/reviews/0001", movie_review_path(movie_id: "0001", id: "0001")
 
-    get '/movies/00001/reviews/0001'
-    assert_equal 'Not Found', @response.body
-    assert_raises(ActionController::UrlGenerationError){ movie_path(:movie_id => '00001', :id => '00001') }
+    get "/movies/00001/reviews/0001"
+    assert_equal "Not Found", @response.body
+    assert_raises(ActionController::UrlGenerationError) { movie_path(movie_id: "00001", id: "00001") }
 
-    get '/movies/0001/trailer'
-    assert_equal 'trailers#show', @response.body
-    assert_equal '/movies/0001/trailer', movie_trailer_path(:movie_id => '0001')
+    get "/movies/0001/trailer"
+    assert_equal "trailers#show", @response.body
+    assert_equal "/movies/0001/trailer", movie_trailer_path(movie_id: "0001")
 
-    get '/movies/00001/trailer'
-    assert_equal 'Not Found', @response.body
-    assert_raises(ActionController::UrlGenerationError){ movie_trailer_path(:movie_id => '00001') }
+    get "/movies/00001/trailer"
+    assert_equal "Not Found", @response.body
+    assert_raises(ActionController::UrlGenerationError) { movie_trailer_path(movie_id: "00001") }
   end
 
   def test_only_should_be_read_from_scope
     draw do
-      scope :only => [:index, :show] do
+      scope only: [:index, :show] do
         namespace :only do
           resources :clubs do
             resources :players
@@ -2571,34 +2612,34 @@ class TestRoutingMapper < ActionDispatch::IntegrationTest
       end
     end
 
-    get '/only/clubs'
-    assert_equal 'only/clubs#index', @response.body
-    assert_equal '/only/clubs', only_clubs_path
+    get "/only/clubs"
+    assert_equal "only/clubs#index", @response.body
+    assert_equal "/only/clubs", only_clubs_path
 
-    get '/only/clubs/1/edit'
-    assert_equal 'Not Found', @response.body
-    assert_raise(NoMethodError) { edit_only_club_path(:id => '1') }
+    get "/only/clubs/1/edit"
+    assert_equal "Not Found", @response.body
+    assert_raise(NoMethodError) { edit_only_club_path(id: "1") }
 
-    get '/only/clubs/1/players'
-    assert_equal 'only/players#index', @response.body
-    assert_equal '/only/clubs/1/players', only_club_players_path(:club_id => '1')
+    get "/only/clubs/1/players"
+    assert_equal "only/players#index", @response.body
+    assert_equal "/only/clubs/1/players", only_club_players_path(club_id: "1")
 
-    get '/only/clubs/1/players/2/edit'
-    assert_equal 'Not Found', @response.body
-    assert_raise(NoMethodError) { edit_only_club_player_path(:club_id => '1', :id => '2') }
+    get "/only/clubs/1/players/2/edit"
+    assert_equal "Not Found", @response.body
+    assert_raise(NoMethodError) { edit_only_club_player_path(club_id: "1", id: "2") }
 
-    get '/only/clubs/1/chairman'
-    assert_equal 'only/chairmen#show', @response.body
-    assert_equal '/only/clubs/1/chairman', only_club_chairman_path(:club_id => '1')
+    get "/only/clubs/1/chairman"
+    assert_equal "only/chairmen#show", @response.body
+    assert_equal "/only/clubs/1/chairman", only_club_chairman_path(club_id: "1")
 
-    get '/only/clubs/1/chairman/edit'
-    assert_equal 'Not Found', @response.body
-    assert_raise(NoMethodError) { edit_only_club_chairman_path(:club_id => '1') }
+    get "/only/clubs/1/chairman/edit"
+    assert_equal "Not Found", @response.body
+    assert_raise(NoMethodError) { edit_only_club_chairman_path(club_id: "1") }
   end
 
   def test_except_should_be_read_from_scope
     draw do
-      scope :except => [:new, :create, :edit, :update, :destroy] do
+      scope except: [:new, :create, :edit, :update, :destroy] do
         namespace :except do
           resources :clubs do
             resources :players
@@ -2608,54 +2649,54 @@ class TestRoutingMapper < ActionDispatch::IntegrationTest
       end
     end
 
-    get '/except/clubs'
-    assert_equal 'except/clubs#index', @response.body
-    assert_equal '/except/clubs', except_clubs_path
+    get "/except/clubs"
+    assert_equal "except/clubs#index", @response.body
+    assert_equal "/except/clubs", except_clubs_path
 
-    get '/except/clubs/1/edit'
-    assert_equal 'Not Found', @response.body
-    assert_raise(NoMethodError) { edit_except_club_path(:id => '1') }
+    get "/except/clubs/1/edit"
+    assert_equal "Not Found", @response.body
+    assert_raise(NoMethodError) { edit_except_club_path(id: "1") }
 
-    get '/except/clubs/1/players'
-    assert_equal 'except/players#index', @response.body
-    assert_equal '/except/clubs/1/players', except_club_players_path(:club_id => '1')
+    get "/except/clubs/1/players"
+    assert_equal "except/players#index", @response.body
+    assert_equal "/except/clubs/1/players", except_club_players_path(club_id: "1")
 
-    get '/except/clubs/1/players/2/edit'
-    assert_equal 'Not Found', @response.body
-    assert_raise(NoMethodError) { edit_except_club_player_path(:club_id => '1', :id => '2') }
+    get "/except/clubs/1/players/2/edit"
+    assert_equal "Not Found", @response.body
+    assert_raise(NoMethodError) { edit_except_club_player_path(club_id: "1", id: "2") }
 
-    get '/except/clubs/1/chairman'
-    assert_equal 'except/chairmen#show', @response.body
-    assert_equal '/except/clubs/1/chairman', except_club_chairman_path(:club_id => '1')
+    get "/except/clubs/1/chairman"
+    assert_equal "except/chairmen#show", @response.body
+    assert_equal "/except/clubs/1/chairman", except_club_chairman_path(club_id: "1")
 
-    get '/except/clubs/1/chairman/edit'
-    assert_equal 'Not Found', @response.body
-    assert_raise(NoMethodError) { edit_except_club_chairman_path(:club_id => '1') }
+    get "/except/clubs/1/chairman/edit"
+    assert_equal "Not Found", @response.body
+    assert_raise(NoMethodError) { edit_except_club_chairman_path(club_id: "1") }
   end
 
   def test_only_option_should_override_scope
     draw do
-      scope :only => :show do
+      scope only: :show do
         namespace :only do
-          resources :sectors, :only => :index
+          resources :sectors, only: :index
         end
       end
     end
 
-    get '/only/sectors'
-    assert_equal 'only/sectors#index', @response.body
-    assert_equal '/only/sectors', only_sectors_path
+    get "/only/sectors"
+    assert_equal "only/sectors#index", @response.body
+    assert_equal "/only/sectors", only_sectors_path
 
-    get '/only/sectors/1'
-    assert_equal 'Not Found', @response.body
-    assert_raise(NoMethodError) { only_sector_path(:id => '1') }
+    get "/only/sectors/1"
+    assert_equal "Not Found", @response.body
+    assert_raise(NoMethodError) { only_sector_path(id: "1") }
   end
 
   def test_only_option_should_not_inherit
     draw do
-      scope :only => :show do
+      scope only: :show do
         namespace :only do
-          resources :sectors, :only => :index do
+          resources :sectors, only: :index do
             resources :companies
             resource  :leader
           end
@@ -2663,38 +2704,38 @@ class TestRoutingMapper < ActionDispatch::IntegrationTest
       end
     end
 
-    get '/only/sectors/1/companies/2'
-    assert_equal 'only/companies#show', @response.body
-    assert_equal '/only/sectors/1/companies/2', only_sector_company_path(:sector_id => '1', :id => '2')
+    get "/only/sectors/1/companies/2"
+    assert_equal "only/companies#show", @response.body
+    assert_equal "/only/sectors/1/companies/2", only_sector_company_path(sector_id: "1", id: "2")
 
-    get '/only/sectors/1/leader'
-    assert_equal 'only/leaders#show', @response.body
-    assert_equal '/only/sectors/1/leader', only_sector_leader_path(:sector_id => '1')
+    get "/only/sectors/1/leader"
+    assert_equal "only/leaders#show", @response.body
+    assert_equal "/only/sectors/1/leader", only_sector_leader_path(sector_id: "1")
   end
 
   def test_except_option_should_override_scope
     draw do
-      scope :except => :index do
+      scope except: :index do
         namespace :except do
-          resources :sectors, :except => [:show, :update, :destroy]
+          resources :sectors, except: [:show, :update, :destroy]
         end
       end
     end
 
-    get '/except/sectors'
-    assert_equal 'except/sectors#index', @response.body
-    assert_equal '/except/sectors', except_sectors_path
+    get "/except/sectors"
+    assert_equal "except/sectors#index", @response.body
+    assert_equal "/except/sectors", except_sectors_path
 
-    get '/except/sectors/1'
-    assert_equal 'Not Found', @response.body
-    assert_raise(NoMethodError) { except_sector_path(:id => '1') }
+    get "/except/sectors/1"
+    assert_equal "Not Found", @response.body
+    assert_raise(NoMethodError) { except_sector_path(id: "1") }
   end
 
   def test_except_option_should_not_inherit
     draw do
-      scope :except => :index do
+      scope except: :index do
         namespace :except do
-          resources :sectors, :except => [:show, :update, :destroy] do
+          resources :sectors, except: [:show, :update, :destroy] do
             resources :companies
             resource  :leader
           end
@@ -2702,62 +2743,62 @@ class TestRoutingMapper < ActionDispatch::IntegrationTest
       end
     end
 
-    get '/except/sectors/1/companies/2'
-    assert_equal 'except/companies#show', @response.body
-    assert_equal '/except/sectors/1/companies/2', except_sector_company_path(:sector_id => '1', :id => '2')
+    get "/except/sectors/1/companies/2"
+    assert_equal "except/companies#show", @response.body
+    assert_equal "/except/sectors/1/companies/2", except_sector_company_path(sector_id: "1", id: "2")
 
-    get '/except/sectors/1/leader'
-    assert_equal 'except/leaders#show', @response.body
-    assert_equal '/except/sectors/1/leader', except_sector_leader_path(:sector_id => '1')
+    get "/except/sectors/1/leader"
+    assert_equal "except/leaders#show", @response.body
+    assert_equal "/except/sectors/1/leader", except_sector_leader_path(sector_id: "1")
   end
 
   def test_except_option_should_override_scoped_only
     draw do
-      scope :only => :show do
+      scope only: :show do
         namespace :only do
-          resources :sectors, :only => :index do
-            resources :managers, :except => [:show, :update, :destroy]
+          resources :sectors, only: :index do
+            resources :managers, except: [:show, :update, :destroy]
           end
         end
       end
     end
 
-    get '/only/sectors/1/managers'
-    assert_equal 'only/managers#index', @response.body
-    assert_equal '/only/sectors/1/managers', only_sector_managers_path(:sector_id => '1')
+    get "/only/sectors/1/managers"
+    assert_equal "only/managers#index", @response.body
+    assert_equal "/only/sectors/1/managers", only_sector_managers_path(sector_id: "1")
 
-    get '/only/sectors/1/managers/2'
-    assert_equal 'Not Found', @response.body
-    assert_raise(NoMethodError) { only_sector_manager_path(:sector_id => '1', :id => '2') }
+    get "/only/sectors/1/managers/2"
+    assert_equal "Not Found", @response.body
+    assert_raise(NoMethodError) { only_sector_manager_path(sector_id: "1", id: "2") }
   end
 
   def test_only_option_should_override_scoped_except
     draw do
-      scope :except => :index do
+      scope except: :index do
         namespace :except do
-          resources :sectors, :except => [:show, :update, :destroy] do
-            resources :managers, :only => :index
+          resources :sectors, except: [:show, :update, :destroy] do
+            resources :managers, only: :index
           end
         end
       end
     end
 
-    get '/except/sectors/1/managers'
-    assert_equal 'except/managers#index', @response.body
-    assert_equal '/except/sectors/1/managers', except_sector_managers_path(:sector_id => '1')
+    get "/except/sectors/1/managers"
+    assert_equal "except/managers#index", @response.body
+    assert_equal "/except/sectors/1/managers", except_sector_managers_path(sector_id: "1")
 
-    get '/except/sectors/1/managers/2'
-    assert_equal 'Not Found', @response.body
-    assert_raise(NoMethodError) { except_sector_manager_path(:sector_id => '1', :id => '2') }
+    get "/except/sectors/1/managers/2"
+    assert_equal "Not Found", @response.body
+    assert_raise(NoMethodError) { except_sector_manager_path(sector_id: "1", id: "2") }
   end
 
   def test_only_scope_should_override_parent_scope
     draw do
-      scope :only => :show do
+      scope only: :show do
         namespace :only do
-          resources :sectors, :only => :index do
+          resources :sectors, only: :index do
             resources :companies do
-              scope :only => :index do
+              scope only: :index do
                 resources :divisions
               end
             end
@@ -2766,22 +2807,22 @@ class TestRoutingMapper < ActionDispatch::IntegrationTest
       end
     end
 
-    get '/only/sectors/1/companies/2/divisions'
-    assert_equal 'only/divisions#index', @response.body
-    assert_equal '/only/sectors/1/companies/2/divisions', only_sector_company_divisions_path(:sector_id => '1', :company_id => '2')
+    get "/only/sectors/1/companies/2/divisions"
+    assert_equal "only/divisions#index", @response.body
+    assert_equal "/only/sectors/1/companies/2/divisions", only_sector_company_divisions_path(sector_id: "1", company_id: "2")
 
-    get '/only/sectors/1/companies/2/divisions/3'
-    assert_equal 'Not Found', @response.body
-    assert_raise(NoMethodError) { only_sector_company_division_path(:sector_id => '1', :company_id => '2', :id => '3') }
+    get "/only/sectors/1/companies/2/divisions/3"
+    assert_equal "Not Found", @response.body
+    assert_raise(NoMethodError) { only_sector_company_division_path(sector_id: "1", company_id: "2", id: "3") }
   end
 
   def test_except_scope_should_override_parent_scope
     draw do
-      scope :except => :index do
+      scope except: :index do
         namespace :except do
-          resources :sectors, :except => [:show, :update, :destroy] do
+          resources :sectors, except: [:show, :update, :destroy] do
             resources :companies do
-              scope :except => [:show, :update, :destroy] do
+              scope except: [:show, :update, :destroy] do
                 resources :divisions
               end
             end
@@ -2790,22 +2831,22 @@ class TestRoutingMapper < ActionDispatch::IntegrationTest
       end
     end
 
-    get '/except/sectors/1/companies/2/divisions'
-    assert_equal 'except/divisions#index', @response.body
-    assert_equal '/except/sectors/1/companies/2/divisions', except_sector_company_divisions_path(:sector_id => '1', :company_id => '2')
+    get "/except/sectors/1/companies/2/divisions"
+    assert_equal "except/divisions#index", @response.body
+    assert_equal "/except/sectors/1/companies/2/divisions", except_sector_company_divisions_path(sector_id: "1", company_id: "2")
 
-    get '/except/sectors/1/companies/2/divisions/3'
-    assert_equal 'Not Found', @response.body
-    assert_raise(NoMethodError) { except_sector_company_division_path(:sector_id => '1', :company_id => '2', :id => '3') }
+    get "/except/sectors/1/companies/2/divisions/3"
+    assert_equal "Not Found", @response.body
+    assert_raise(NoMethodError) { except_sector_company_division_path(sector_id: "1", company_id: "2", id: "3") }
   end
 
   def test_except_scope_should_override_parent_only_scope
     draw do
-      scope :only => :show do
+      scope only: :show do
         namespace :only do
-          resources :sectors, :only => :index do
+          resources :sectors, only: :index do
             resources :companies do
-              scope :except => [:show, :update, :destroy] do
+              scope except: [:show, :update, :destroy] do
                 resources :departments
               end
             end
@@ -2814,22 +2855,22 @@ class TestRoutingMapper < ActionDispatch::IntegrationTest
       end
     end
 
-    get '/only/sectors/1/companies/2/departments'
-    assert_equal 'only/departments#index', @response.body
-    assert_equal '/only/sectors/1/companies/2/departments', only_sector_company_departments_path(:sector_id => '1', :company_id => '2')
+    get "/only/sectors/1/companies/2/departments"
+    assert_equal "only/departments#index", @response.body
+    assert_equal "/only/sectors/1/companies/2/departments", only_sector_company_departments_path(sector_id: "1", company_id: "2")
 
-    get '/only/sectors/1/companies/2/departments/3'
-    assert_equal 'Not Found', @response.body
-    assert_raise(NoMethodError) { only_sector_company_department_path(:sector_id => '1', :company_id => '2', :id => '3') }
+    get "/only/sectors/1/companies/2/departments/3"
+    assert_equal "Not Found", @response.body
+    assert_raise(NoMethodError) { only_sector_company_department_path(sector_id: "1", company_id: "2", id: "3") }
   end
 
   def test_only_scope_should_override_parent_except_scope
     draw do
-      scope :except => :index do
+      scope except: :index do
         namespace :except do
-          resources :sectors, :except => [:show, :update, :destroy] do
+          resources :sectors, except: [:show, :update, :destroy] do
             resources :companies do
-              scope :only => :index do
+              scope only: :index do
                 resources :departments
               end
             end
@@ -2838,13 +2879,13 @@ class TestRoutingMapper < ActionDispatch::IntegrationTest
       end
     end
 
-    get '/except/sectors/1/companies/2/departments'
-    assert_equal 'except/departments#index', @response.body
-    assert_equal '/except/sectors/1/companies/2/departments', except_sector_company_departments_path(:sector_id => '1', :company_id => '2')
+    get "/except/sectors/1/companies/2/departments"
+    assert_equal "except/departments#index", @response.body
+    assert_equal "/except/sectors/1/companies/2/departments", except_sector_company_departments_path(sector_id: "1", company_id: "2")
 
-    get '/except/sectors/1/companies/2/departments/3'
-    assert_equal 'Not Found', @response.body
-    assert_raise(NoMethodError) { except_sector_company_department_path(:sector_id => '1', :company_id => '2', :id => '3') }
+    get "/except/sectors/1/companies/2/departments/3"
+    assert_equal "Not Found", @response.body
+    assert_raise(NoMethodError) { except_sector_company_department_path(sector_id: "1", company_id: "2", id: "3") }
   end
 
   def test_resources_are_not_pluralized
@@ -2854,30 +2895,30 @@ class TestRoutingMapper < ActionDispatch::IntegrationTest
       end
     end
 
-    get '/transport/taxis'
-    assert_equal 'transport/taxis#index', @response.body
-    assert_equal '/transport/taxis', transport_taxis_path
+    get "/transport/taxis"
+    assert_equal "transport/taxis#index", @response.body
+    assert_equal "/transport/taxis", transport_taxis_path
 
-    get '/transport/taxis/new'
-    assert_equal 'transport/taxis#new', @response.body
-    assert_equal '/transport/taxis/new', new_transport_taxi_path
+    get "/transport/taxis/new"
+    assert_equal "transport/taxis#new", @response.body
+    assert_equal "/transport/taxis/new", new_transport_taxi_path
 
-    post '/transport/taxis'
-    assert_equal 'transport/taxis#create', @response.body
+    post "/transport/taxis"
+    assert_equal "transport/taxis#create", @response.body
 
-    get '/transport/taxis/1'
-    assert_equal 'transport/taxis#show', @response.body
-    assert_equal '/transport/taxis/1', transport_taxi_path(:id => '1')
+    get "/transport/taxis/1"
+    assert_equal "transport/taxis#show", @response.body
+    assert_equal "/transport/taxis/1", transport_taxi_path(id: "1")
 
-    get '/transport/taxis/1/edit'
-    assert_equal 'transport/taxis#edit', @response.body
-    assert_equal '/transport/taxis/1/edit', edit_transport_taxi_path(:id => '1')
+    get "/transport/taxis/1/edit"
+    assert_equal "transport/taxis#edit", @response.body
+    assert_equal "/transport/taxis/1/edit", edit_transport_taxi_path(id: "1")
 
-    put '/transport/taxis/1'
-    assert_equal 'transport/taxis#update', @response.body
+    put "/transport/taxis/1"
+    assert_equal "transport/taxis#update", @response.body
 
-    delete '/transport/taxis/1'
-    assert_equal 'transport/taxis#destroy', @response.body
+    delete "/transport/taxis/1"
+    assert_equal "transport/taxis#destroy", @response.body
   end
 
   def test_singleton_resources_are_not_singularized
@@ -2887,169 +2928,169 @@ class TestRoutingMapper < ActionDispatch::IntegrationTest
       end
     end
 
-    get '/medical/taxis/new'
-    assert_equal 'medical/taxis#new', @response.body
-    assert_equal '/medical/taxis/new', new_medical_taxis_path
+    get "/medical/taxis/new"
+    assert_equal "medical/taxis#new", @response.body
+    assert_equal "/medical/taxis/new", new_medical_taxis_path
 
-    post '/medical/taxis'
-    assert_equal 'medical/taxis#create', @response.body
+    post "/medical/taxis"
+    assert_equal "medical/taxis#create", @response.body
 
-    get '/medical/taxis'
-    assert_equal 'medical/taxis#show', @response.body
-    assert_equal '/medical/taxis', medical_taxis_path
+    get "/medical/taxis"
+    assert_equal "medical/taxis#show", @response.body
+    assert_equal "/medical/taxis", medical_taxis_path
 
-    get '/medical/taxis/edit'
-    assert_equal 'medical/taxis#edit', @response.body
-    assert_equal '/medical/taxis/edit', edit_medical_taxis_path
+    get "/medical/taxis/edit"
+    assert_equal "medical/taxis#edit", @response.body
+    assert_equal "/medical/taxis/edit", edit_medical_taxis_path
 
-    put '/medical/taxis'
-    assert_equal 'medical/taxis#update', @response.body
+    put "/medical/taxis"
+    assert_equal "medical/taxis#update", @response.body
 
-    delete '/medical/taxis'
-    assert_equal 'medical/taxis#destroy', @response.body
+    delete "/medical/taxis"
+    assert_equal "medical/taxis#destroy", @response.body
   end
 
   def test_greedy_resource_id_regexp_doesnt_match_edit_and_custom_action
     draw do
-      resources :sections, :id => /.+/ do
-        get :preview, :on => :member
+      resources :sections, id: /.+/ do
+        get :preview, on: :member
       end
     end
 
-    get '/sections/1/edit'
-    assert_equal 'sections#edit', @response.body
-    assert_equal '/sections/1/edit', edit_section_path(:id => '1')
+    get "/sections/1/edit"
+    assert_equal "sections#edit", @response.body
+    assert_equal "/sections/1/edit", edit_section_path(id: "1")
 
-    get '/sections/1/preview'
-    assert_equal 'sections#preview', @response.body
-    assert_equal '/sections/1/preview', preview_section_path(:id => '1')
+    get "/sections/1/preview"
+    assert_equal "sections#preview", @response.body
+    assert_equal "/sections/1/preview", preview_section_path(id: "1")
   end
 
   def test_resource_constraints_are_pushed_to_scope
     draw do
       namespace :wiki do
-        resources :articles, :id => /[^\/]+/ do
-          resources :comments, :only => [:create, :new]
+        resources :articles, id: /[^\/]+/ do
+          resources :comments, only: [:create, :new]
         end
       end
     end
 
-    get '/wiki/articles/Ruby_on_Rails_3.0'
-    assert_equal 'wiki/articles#show', @response.body
-    assert_equal '/wiki/articles/Ruby_on_Rails_3.0', wiki_article_path(:id => 'Ruby_on_Rails_3.0')
+    get "/wiki/articles/Ruby_on_Rails_3.0"
+    assert_equal "wiki/articles#show", @response.body
+    assert_equal "/wiki/articles/Ruby_on_Rails_3.0", wiki_article_path(id: "Ruby_on_Rails_3.0")
 
-    get '/wiki/articles/Ruby_on_Rails_3.0/comments/new'
-    assert_equal 'wiki/comments#new', @response.body
-    assert_equal '/wiki/articles/Ruby_on_Rails_3.0/comments/new', new_wiki_article_comment_path(:article_id => 'Ruby_on_Rails_3.0')
+    get "/wiki/articles/Ruby_on_Rails_3.0/comments/new"
+    assert_equal "wiki/comments#new", @response.body
+    assert_equal "/wiki/articles/Ruby_on_Rails_3.0/comments/new", new_wiki_article_comment_path(article_id: "Ruby_on_Rails_3.0")
 
-    post '/wiki/articles/Ruby_on_Rails_3.0/comments'
-    assert_equal 'wiki/comments#create', @response.body
-    assert_equal '/wiki/articles/Ruby_on_Rails_3.0/comments', wiki_article_comments_path(:article_id => 'Ruby_on_Rails_3.0')
+    post "/wiki/articles/Ruby_on_Rails_3.0/comments"
+    assert_equal "wiki/comments#create", @response.body
+    assert_equal "/wiki/articles/Ruby_on_Rails_3.0/comments", wiki_article_comments_path(article_id: "Ruby_on_Rails_3.0")
   end
 
   def test_resources_path_can_be_a_symbol
     draw do
-      resources :wiki_pages, :path => :pages
-      resource :wiki_account, :path => :my_account
+      resources :wiki_pages, path: :pages
+      resource :wiki_account, path: :my_account
     end
 
-    get '/pages'
-    assert_equal 'wiki_pages#index', @response.body
-    assert_equal '/pages', wiki_pages_path
+    get "/pages"
+    assert_equal "wiki_pages#index", @response.body
+    assert_equal "/pages", wiki_pages_path
 
-    get '/pages/Ruby_on_Rails'
-    assert_equal 'wiki_pages#show', @response.body
-    assert_equal '/pages/Ruby_on_Rails', wiki_page_path(:id => 'Ruby_on_Rails')
+    get "/pages/Ruby_on_Rails"
+    assert_equal "wiki_pages#show", @response.body
+    assert_equal "/pages/Ruby_on_Rails", wiki_page_path(id: "Ruby_on_Rails")
 
-    get '/my_account'
-    assert_equal 'wiki_accounts#show', @response.body
-    assert_equal '/my_account', wiki_account_path
+    get "/my_account"
+    assert_equal "wiki_accounts#show", @response.body
+    assert_equal "/my_account", wiki_account_path
   end
 
   def test_redirect_https
     draw do
-      get 'secure', :to => redirect("/secure/login")
+      get "secure", to: redirect("/secure/login")
     end
 
     with_https do
-      get '/secure'
-      verify_redirect 'https://www.example.com/secure/login'
+      get "/secure"
+      verify_redirect "https://www.example.com/secure/login"
     end
   end
 
   def test_path_parameters_is_not_stale
     draw do
-      scope '/countries/:country', :constraints => lambda { |params, req| %w(all France).include?(params[:country]) } do
-        get '/',       :to => 'countries#index'
-        get '/cities', :to => 'countries#cities'
+      scope "/countries/:country", constraints: lambda { |params, req| %w(all France).include?(params[:country]) } do
+        get "/",       to: "countries#index"
+        get "/cities", to: "countries#cities"
       end
 
-      get '/countries/:country/(*other)', :to => redirect{ |params, req| params[:other] ? "/countries/all/#{params[:other]}" : '/countries/all' }
+      get "/countries/:country/(*other)", to: redirect { |params, req| params[:other] ? "/countries/all/#{params[:other]}" : "/countries/all" }
     end
 
-    get '/countries/France'
-    assert_equal 'countries#index', @response.body
+    get "/countries/France"
+    assert_equal "countries#index", @response.body
 
-    get '/countries/France/cities'
-    assert_equal 'countries#cities', @response.body
+    get "/countries/France/cities"
+    assert_equal "countries#cities", @response.body
 
-    get '/countries/UK'
-    verify_redirect 'http://www.example.com/countries/all'
+    get "/countries/UK"
+    verify_redirect "http://www.example.com/countries/all"
 
-    get '/countries/UK/cities'
-    verify_redirect 'http://www.example.com/countries/all/cities'
+    get "/countries/UK/cities"
+    verify_redirect "http://www.example.com/countries/all/cities"
   end
 
   def test_constraints_block_not_carried_to_following_routes
     draw do
-      scope '/italians' do
-        get '/writers', :to => 'italians#writers', :constraints => ::TestRoutingMapper::IpRestrictor
-        get '/sculptors', :to => 'italians#sculptors'
-        get '/painters/:painter', :to => 'italians#painters', :constraints => {:painter => /michelangelo/}
+      scope "/italians" do
+        get "/writers", to: "italians#writers", constraints: ::TestRoutingMapper::IpRestrictor
+        get "/sculptors", to: "italians#sculptors"
+        get "/painters/:painter", to: "italians#painters", constraints: { painter: /michelangelo/ }
       end
     end
 
-    get '/italians/writers'
-    assert_equal 'Not Found', @response.body
+    get "/italians/writers"
+    assert_equal "Not Found", @response.body
 
-    get '/italians/sculptors'
-    assert_equal 'italians#sculptors', @response.body
+    get "/italians/sculptors"
+    assert_equal "italians#sculptors", @response.body
 
-    get '/italians/painters/botticelli'
-    assert_equal 'Not Found', @response.body
+    get "/italians/painters/botticelli"
+    assert_equal "Not Found", @response.body
 
-    get '/italians/painters/michelangelo'
-    assert_equal 'italians#painters', @response.body
+    get "/italians/painters/michelangelo"
+    assert_equal "italians#painters", @response.body
   end
 
   def test_custom_resource_actions_defined_using_string
     draw do
       resources :customers do
         resources :invoices do
-          get "aged/:months", :on => :collection, :action => :aged, :as => :aged
+          get "aged/:months", on: :collection, action: :aged, as: :aged
         end
 
-        get "inactive", :on => :collection
-        post "deactivate", :on => :member
-        get "old", :on => :collection, :as => :stale
+        get "inactive", on: :collection
+        post "deactivate", on: :member
+        get "old", on: :collection, as: :stale
       end
     end
 
-    get '/customers/inactive'
-    assert_equal 'customers#inactive', @response.body
-    assert_equal '/customers/inactive', inactive_customers_path
+    get "/customers/inactive"
+    assert_equal "customers#inactive", @response.body
+    assert_equal "/customers/inactive", inactive_customers_path
 
-    post '/customers/1/deactivate'
-    assert_equal 'customers#deactivate', @response.body
-    assert_equal '/customers/1/deactivate', deactivate_customer_path(:id => '1')
+    post "/customers/1/deactivate"
+    assert_equal "customers#deactivate", @response.body
+    assert_equal "/customers/1/deactivate", deactivate_customer_path(id: "1")
 
-    get '/customers/old'
-    assert_equal 'customers#old', @response.body
-    assert_equal '/customers/old', stale_customers_path
+    get "/customers/old"
+    assert_equal "customers#old", @response.body
+    assert_equal "/customers/old", stale_customers_path
 
-    get '/customers/1/invoices/aged/3'
-    assert_equal 'invoices#aged', @response.body
-    assert_equal '/customers/1/invoices/aged/3', aged_customer_invoices_path(:customer_id => '1', :months => '3')
+    get "/customers/1/invoices/aged/3"
+    assert_equal "invoices#aged", @response.body
+    assert_equal "/customers/1/invoices/aged/3", aged_customer_invoices_path(customer_id: "1", months: "3")
   end
 
   def test_route_defined_in_resources_scope_level
@@ -3059,43 +3100,43 @@ class TestRoutingMapper < ActionDispatch::IntegrationTest
       end
     end
 
-    get '/customers/1/export'
-    assert_equal 'customers#export', @response.body
-    assert_equal '/customers/1/export', customer_export_path(:customer_id => '1')
+    get "/customers/1/export"
+    assert_equal "customers#export", @response.body
+    assert_equal "/customers/1/export", customer_export_path(customer_id: "1")
   end
 
   def test_named_character_classes_in_regexp_constraints
     draw do
-      get '/purchases/:token/:filename',
-        :to => 'purchases#fetch',
-        :token => /[[:alnum:]]{10}/,
-        :filename => /(.+)/,
-        :as => :purchase
+      get "/purchases/:token/:filename",
+        to: "purchases#fetch",
+        token: /[[:alnum:]]{10}/,
+        filename: /(.+)/,
+        as: :purchase
     end
 
-    get '/purchases/315004be7e/Ruby_on_Rails_3.pdf'
-    assert_equal 'purchases#fetch', @response.body
-    assert_equal '/purchases/315004be7e/Ruby_on_Rails_3.pdf', purchase_path(:token => '315004be7e', :filename => 'Ruby_on_Rails_3.pdf')
+    get "/purchases/315004be7e/Ruby_on_Rails_3.pdf"
+    assert_equal "purchases#fetch", @response.body
+    assert_equal "/purchases/315004be7e/Ruby_on_Rails_3.pdf", purchase_path(token: "315004be7e", filename: "Ruby_on_Rails_3.pdf")
   end
 
   def test_nested_resource_constraints
     draw do
-      resources :lists, :id => /([A-Za-z0-9]{25})|default/ do
-        resources :todos, :id => /\d+/
+      resources :lists, id: /([A-Za-z0-9]{25})|default/ do
+        resources :todos, id: /\d+/
       end
     end
 
-    get '/lists/01234012340123401234fffff'
-    assert_equal 'lists#show', @response.body
-    assert_equal '/lists/01234012340123401234fffff', list_path(:id => '01234012340123401234fffff')
+    get "/lists/01234012340123401234fffff"
+    assert_equal "lists#show", @response.body
+    assert_equal "/lists/01234012340123401234fffff", list_path(id: "01234012340123401234fffff")
 
-    get '/lists/01234012340123401234fffff/todos/1'
-    assert_equal 'todos#show', @response.body
-    assert_equal '/lists/01234012340123401234fffff/todos/1', list_todo_path(:list_id => '01234012340123401234fffff', :id => '1')
+    get "/lists/01234012340123401234fffff/todos/1"
+    assert_equal "todos#show", @response.body
+    assert_equal "/lists/01234012340123401234fffff/todos/1", list_todo_path(list_id: "01234012340123401234fffff", id: "1")
 
-    get '/lists/2/todos/1'
-    assert_equal 'Not Found', @response.body
-    assert_raises(ActionController::UrlGenerationError){ list_todo_path(:list_id => '2', :id => '1') }
+    get "/lists/2/todos/1"
+    assert_equal "Not Found", @response.body
+    assert_raises(ActionController::UrlGenerationError) { list_todo_path(list_id: "2", id: "1") }
   end
 
   def test_redirect_argument_error
@@ -3118,10 +3159,10 @@ class TestRoutingMapper < ActionDispatch::IntegrationTest
 
   def test_explicitly_avoiding_the_named_route
     draw do
-      scope :as => "routes" do
-        get "/c/:id", :as => :collision, :to => "collision#show"
-        get "/collision", :to => "collision#show"
-        get "/no_collision", :to => "collision#show", :as => nil
+      scope as: "routes" do
+        get "/c/:id", as: :collision, to: "collision#show"
+        get "/collision", to: "collision#show"
+        get "/no_collision", to: "collision#show", as: nil
       end
     end
 
@@ -3130,49 +3171,49 @@ class TestRoutingMapper < ActionDispatch::IntegrationTest
 
   def test_controller_name_with_leading_slash_raise_error
     assert_raise(ArgumentError) do
-      draw { get '/feeds/:service', :to => '/feeds#show' }
+      draw { get "/feeds/:service", to: "/feeds#show" }
     end
 
     assert_raise(ArgumentError) do
-      draw { get '/feeds/:service', :controller => '/feeds', :action => 'show' }
+      draw { get "/feeds/:service", controller: "/feeds", action: "show" }
     end
 
     assert_raise(ArgumentError) do
-      draw { get '/api/feeds/:service', :to => '/api/feeds#show' }
+      draw { get "/api/feeds/:service", to: "/api/feeds#show" }
     end
 
     assert_raise(ArgumentError) do
-      draw { resources :feeds, :controller => '/feeds' }
+      draw { resources :feeds, controller: "/feeds" }
     end
   end
 
   def test_invalid_route_name_raises_error
     assert_raise(ArgumentError) do
-      draw { get '/products', :to => 'products#index', :as => 'products ' }
+      draw { get "/products", to: "products#index", as: "products " }
     end
 
     assert_raise(ArgumentError) do
-      draw { get '/products', :to => 'products#index', :as => ' products' }
+      draw { get "/products", to: "products#index", as: " products" }
     end
 
     assert_raise(ArgumentError) do
-      draw { get '/products', :to => 'products#index', :as => 'products!' }
+      draw { get "/products", to: "products#index", as: "products!" }
     end
 
     assert_raise(ArgumentError) do
-      draw { get '/products', :to => 'products#index', :as => 'products index' }
+      draw { get "/products", to: "products#index", as: "products index" }
     end
 
     assert_raise(ArgumentError) do
-      draw { get '/products', :to => 'products#index', :as => '1products' }
+      draw { get "/products", to: "products#index", as: "1products" }
     end
   end
 
   def test_duplicate_route_name_raises_error
     assert_raise(ArgumentError) do
       draw do
-        get '/collision', :to => 'collision#show', :as => 'collision'
-        get '/duplicate', :to => 'duplicate#show', :as => 'collision'
+        get "/collision", to: "collision#show", as: "collision"
+        get "/duplicate", to: "duplicate#show", as: "collision"
       end
     end
   end
@@ -3181,15 +3222,15 @@ class TestRoutingMapper < ActionDispatch::IntegrationTest
     assert_raise(ArgumentError) do
       draw do
         resources :collisions
-        get '/collision', :to => 'collision#show', :as => 'collision'
+        get "/collision", to: "collision#show", as: "collision"
       end
     end
   end
 
   def test_nested_route_in_nested_resource
     draw do
-      resources :posts, :only => [:index, :show] do
-        resources :comments, :except => :destroy do
+      resources :posts, only: [:index, :show] do
+        resources :comments, except: :destroy do
           get "views" => "comments#views", :as => :views
         end
       end
@@ -3197,124 +3238,124 @@ class TestRoutingMapper < ActionDispatch::IntegrationTest
 
     get "/posts/1/comments/2/views"
     assert_equal "comments#views", @response.body
-    assert_equal "/posts/1/comments/2/views", post_comment_views_path(:post_id => '1', :comment_id => '2')
+    assert_equal "/posts/1/comments/2/views", post_comment_views_path(post_id: "1", comment_id: "2")
   end
 
   def test_root_in_deeply_nested_scope
     draw do
-      resources :posts, :only => [:index, :show] do
+      resources :posts, only: [:index, :show] do
         namespace :admin do
-          root :to => "index#index"
+          root to: "index#index"
         end
       end
     end
 
     get "/posts/1/admin"
     assert_equal "admin/index#index", @response.body
-    assert_equal "/posts/1/admin", post_admin_root_path(:post_id => '1')
+    assert_equal "/posts/1/admin", post_admin_root_path(post_id: "1")
   end
 
   def test_custom_param
     draw do
-      resources :profiles, :param => :username do
-        get :details, :on => :member
+      resources :profiles, param: :username do
+        get :details, on: :member
         resources :messages
       end
     end
 
-    get '/profiles/bob'
-    assert_equal 'profiles#show', @response.body
-    assert_equal 'bob', @request.params[:username]
+    get "/profiles/bob"
+    assert_equal "profiles#show", @response.body
+    assert_equal "bob", @request.params[:username]
 
-    get '/profiles/bob/details'
-    assert_equal 'bob', @request.params[:username]
+    get "/profiles/bob/details"
+    assert_equal "bob", @request.params[:username]
 
-    get '/profiles/bob/messages/34'
-    assert_equal 'bob', @request.params[:profile_username]
-    assert_equal '34', @request.params[:id]
+    get "/profiles/bob/messages/34"
+    assert_equal "bob", @request.params[:profile_username]
+    assert_equal "34", @request.params[:id]
   end
 
   def test_custom_param_constraint
     draw do
-      resources :profiles, :param => :username, :username => /[a-z]+/ do
-        get :details, :on => :member
+      resources :profiles, param: :username, username: /[a-z]+/ do
+        get :details, on: :member
         resources :messages
       end
     end
 
-    get '/profiles/bob1'
+    get "/profiles/bob1"
     assert_equal 404, @response.status
 
-    get '/profiles/bob1/details'
+    get "/profiles/bob1/details"
     assert_equal 404, @response.status
 
-    get '/profiles/bob1/messages/34'
+    get "/profiles/bob1/messages/34"
     assert_equal 404, @response.status
   end
 
   def test_shallow_custom_param
     draw do
       resources :orders do
-        constraints :download => /[0-9a-f]{8}-(?:[0-9a-f]{4}-){3}[0-9a-f]{12}/ do
-          resources :downloads, :param => :download, :shallow => true
+        constraints download: /[0-9a-f]{8}-(?:[0-9a-f]{4}-){3}[0-9a-f]{12}/ do
+          resources :downloads, param: :download, shallow: true
         end
       end
     end
 
-    get '/downloads/0c0c0b68-d24b-11e1-a861-001ff3fffe6f.zip'
-    assert_equal 'downloads#show', @response.body
-    assert_equal '0c0c0b68-d24b-11e1-a861-001ff3fffe6f', @request.params[:download]
+    get "/downloads/0c0c0b68-d24b-11e1-a861-001ff3fffe6f.zip"
+    assert_equal "downloads#show", @response.body
+    assert_equal "0c0c0b68-d24b-11e1-a861-001ff3fffe6f", @request.params[:download]
   end
 
   def test_action_from_path_is_not_frozen
     draw do
-      get 'search' => 'search'
+      get "search" => "search"
     end
 
-    get '/search'
+    get "/search"
     assert !@request.params[:action].frozen?
   end
 
   def test_multiple_positional_args_with_the_same_name
     draw do
-      get '/downloads/:id/:id.tar' => 'downloads#show', as: :download, format: false
+      get "/downloads/:id/:id.tar" => "downloads#show", as: :download, format: false
     end
 
     expected_params = {
-      controller: 'downloads',
-      action:     'show',
-      id:         '1'
+      controller: "downloads",
+      action:     "show",
+      id:         "1"
     }
 
-    get '/downloads/1/1.tar'
-    assert_equal 'downloads#show', @response.body
+    get "/downloads/1/1.tar"
+    assert_equal "downloads#show", @response.body
     assert_equal expected_params, @request.path_parameters
-    assert_equal '/downloads/1/1.tar', download_path('1')
-    assert_equal '/downloads/1/1.tar', download_path('1', '1')
+    assert_equal "/downloads/1/1.tar", download_path("1")
+    assert_equal "/downloads/1/1.tar", download_path("1", "1")
   end
 
   def test_absolute_controller_namespace
     draw do
       namespace :foo do
-        get '/', to: '/bar#index', as: 'root'
+        get "/", to: "/bar#index", as: "root"
       end
     end
 
-    get '/foo'
-    assert_equal 'bar#index', @response.body
-    assert_equal '/foo', foo_root_path
+    get "/foo"
+    assert_equal "bar#index", @response.body
+    assert_equal "/foo", foo_root_path
   end
 
   def test_namespace_as_controller
     draw do
       namespace :foo do
-        get '/', to: '/bar#index', as: 'root'
+        get "/", to: "/bar#index", as: "root"
       end
     end
 
-    get '/foo'
-    assert_equal 'bar#index', @response.body
-    assert_equal '/foo', foo_root_path
+    get "/foo"
+    assert_equal "bar#index", @response.body
+    assert_equal "/foo", foo_root_path
   end
 
   def test_trailing_slash
@@ -3322,63 +3363,63 @@ class TestRoutingMapper < ActionDispatch::IntegrationTest
       resources :streams
     end
 
-    get '/streams'
-    assert @response.ok?, 'route without trailing slash should work'
+    get "/streams"
+    assert @response.ok?, "route without trailing slash should work"
 
-    get '/streams/'
-    assert @response.ok?, 'route with trailing slash should work'
+    get "/streams/"
+    assert @response.ok?, "route with trailing slash should work"
 
-    get '/streams?foobar'
-    assert @response.ok?, 'route without trailing slash and with QUERY_STRING should work'
+    get "/streams?foobar"
+    assert @response.ok?, "route without trailing slash and with QUERY_STRING should work"
 
-    get '/streams/?foobar'
-    assert @response.ok?, 'route with trailing slash and with QUERY_STRING should work'
+    get "/streams/?foobar"
+    assert @response.ok?, "route with trailing slash and with QUERY_STRING should work"
   end
 
   def test_route_with_dashes_in_path
     draw do
-      get '/contact-us', to: 'pages#contact_us'
+      get "/contact-us", to: "pages#contact_us"
     end
 
-    get '/contact-us'
-    assert_equal 'pages#contact_us', @response.body
-    assert_equal '/contact-us', contact_us_path
+    get "/contact-us"
+    assert_equal "pages#contact_us", @response.body
+    assert_equal "/contact-us", contact_us_path
   end
 
   def test_shorthand_route_with_dashes_in_path
     draw do
-      get '/about-us/index'
+      get "/about-us/index"
     end
 
-    get '/about-us/index'
-    assert_equal 'about_us#index', @response.body
-    assert_equal '/about-us/index', about_us_index_path
+    get "/about-us/index"
+    assert_equal "about_us#index", @response.body
+    assert_equal "/about-us/index", about_us_index_path
   end
 
   def test_resource_routes_with_dashes_in_path
     draw do
       resources :photos, only: [:show] do
-        get 'user-favorites', on: :collection
-        get 'preview-photo', on: :member
-        get 'summary-text'
+        get "user-favorites", on: :collection
+        get "preview-photo", on: :member
+        get "summary-text"
       end
     end
 
-    get '/photos/user-favorites'
-    assert_equal 'photos#user_favorites', @response.body
-    assert_equal '/photos/user-favorites', user_favorites_photos_path
+    get "/photos/user-favorites"
+    assert_equal "photos#user_favorites", @response.body
+    assert_equal "/photos/user-favorites", user_favorites_photos_path
 
-    get '/photos/1/preview-photo'
-    assert_equal 'photos#preview_photo', @response.body
-    assert_equal '/photos/1/preview-photo', preview_photo_photo_path('1')
+    get "/photos/1/preview-photo"
+    assert_equal "photos#preview_photo", @response.body
+    assert_equal "/photos/1/preview-photo", preview_photo_photo_path("1")
 
-    get '/photos/1/summary-text'
-    assert_equal 'photos#summary_text', @response.body
-    assert_equal '/photos/1/summary-text', photo_summary_text_path('1')
+    get "/photos/1/summary-text"
+    assert_equal "photos#summary_text", @response.body
+    assert_equal "/photos/1/summary-text", photo_summary_text_path("1")
 
-    get '/photos/1'
-    assert_equal 'photos#show', @response.body
-    assert_equal '/photos/1', photo_path('1')
+    get "/photos/1"
+    assert_equal "photos#show", @response.body
+    assert_equal "/photos/1", photo_path("1")
   end
 
   def test_shallow_path_inside_namespace_is_not_added_twice
@@ -3392,228 +3433,228 @@ class TestRoutingMapper < ActionDispatch::IntegrationTest
       end
     end
 
-    get '/admin/posts/1/comments'
-    assert_equal 'admin/comments#index', @response.body
-    assert_equal '/admin/posts/1/comments', admin_post_comments_path('1')
+    get "/admin/posts/1/comments"
+    assert_equal "admin/comments#index", @response.body
+    assert_equal "/admin/posts/1/comments", admin_post_comments_path("1")
   end
 
   def test_mix_string_to_controller_action
     draw do
-      get '/projects', controller: 'project_files',
-                       action: 'index',
-                       to: 'comments#index'
+      get "/projects", controller: "project_files",
+                       action: "index",
+                       to: "comments#index"
     end
-    get '/projects'
-    assert_equal 'comments#index', @response.body
+    get "/projects"
+    assert_equal "comments#index", @response.body
   end
 
   def test_mix_string_to_controller
     draw do
-      get '/projects', controller: 'project_files',
-                       to: 'comments#index'
+      get "/projects", controller: "project_files",
+                       to: "comments#index"
     end
-    get '/projects'
-    assert_equal 'comments#index', @response.body
+    get "/projects"
+    assert_equal "comments#index", @response.body
   end
 
   def test_mix_string_to_action
     draw do
-      get '/projects', action: 'index',
-                       to: 'comments#index'
+      get "/projects", action: "index",
+                       to: "comments#index"
     end
-    get '/projects'
-    assert_equal 'comments#index', @response.body
+    get "/projects"
+    assert_equal "comments#index", @response.body
   end
 
   def test_shallow_path_and_prefix_are_not_added_to_non_shallow_routes
     draw do
-      scope shallow_path: 'projects', shallow_prefix: 'project' do
+      scope shallow_path: "projects", shallow_prefix: "project" do
         resources :projects do
-          resources :files, controller: 'project_files', shallow: true
+          resources :files, controller: "project_files", shallow: true
         end
       end
     end
 
-    get '/projects'
-    assert_equal 'projects#index', @response.body
-    assert_equal '/projects', projects_path
+    get "/projects"
+    assert_equal "projects#index", @response.body
+    assert_equal "/projects", projects_path
 
-    get '/projects/new'
-    assert_equal 'projects#new', @response.body
-    assert_equal '/projects/new', new_project_path
+    get "/projects/new"
+    assert_equal "projects#new", @response.body
+    assert_equal "/projects/new", new_project_path
 
-    post '/projects'
-    assert_equal 'projects#create', @response.body
+    post "/projects"
+    assert_equal "projects#create", @response.body
 
-    get '/projects/1'
-    assert_equal 'projects#show', @response.body
-    assert_equal '/projects/1', project_path('1')
+    get "/projects/1"
+    assert_equal "projects#show", @response.body
+    assert_equal "/projects/1", project_path("1")
 
-    get '/projects/1/edit'
-    assert_equal 'projects#edit', @response.body
-    assert_equal '/projects/1/edit', edit_project_path('1')
+    get "/projects/1/edit"
+    assert_equal "projects#edit", @response.body
+    assert_equal "/projects/1/edit", edit_project_path("1")
 
-    patch '/projects/1'
-    assert_equal 'projects#update', @response.body
+    patch "/projects/1"
+    assert_equal "projects#update", @response.body
 
-    delete '/projects/1'
-    assert_equal 'projects#destroy', @response.body
+    delete "/projects/1"
+    assert_equal "projects#destroy", @response.body
 
-    get '/projects/1/files'
-    assert_equal 'project_files#index', @response.body
-    assert_equal '/projects/1/files', project_files_path('1')
+    get "/projects/1/files"
+    assert_equal "project_files#index", @response.body
+    assert_equal "/projects/1/files", project_files_path("1")
 
-    get '/projects/1/files/new'
-    assert_equal 'project_files#new', @response.body
-    assert_equal '/projects/1/files/new', new_project_file_path('1')
+    get "/projects/1/files/new"
+    assert_equal "project_files#new", @response.body
+    assert_equal "/projects/1/files/new", new_project_file_path("1")
 
-    post '/projects/1/files'
-    assert_equal 'project_files#create', @response.body
+    post "/projects/1/files"
+    assert_equal "project_files#create", @response.body
 
-    get '/projects/files/2'
-    assert_equal 'project_files#show', @response.body
-    assert_equal '/projects/files/2', project_file_path('2')
+    get "/projects/files/2"
+    assert_equal "project_files#show", @response.body
+    assert_equal "/projects/files/2", project_file_path("2")
 
-    get '/projects/files/2/edit'
-    assert_equal 'project_files#edit', @response.body
-    assert_equal '/projects/files/2/edit', edit_project_file_path('2')
+    get "/projects/files/2/edit"
+    assert_equal "project_files#edit", @response.body
+    assert_equal "/projects/files/2/edit", edit_project_file_path("2")
 
-    patch '/projects/files/2'
-    assert_equal 'project_files#update', @response.body
+    patch "/projects/files/2"
+    assert_equal "project_files#update", @response.body
 
-    delete '/projects/files/2'
-    assert_equal 'project_files#destroy', @response.body
+    delete "/projects/files/2"
+    assert_equal "project_files#destroy", @response.body
   end
 
   def test_scope_path_is_copied_to_shallow_path
     draw do
-      scope path: 'foo' do
+      scope path: "foo" do
         resources :posts do
           resources :comments, shallow: true
         end
       end
     end
 
-    assert_equal '/foo/comments/1', comment_path('1')
+    assert_equal "/foo/comments/1", comment_path("1")
   end
 
   def test_scope_as_is_copied_to_shallow_prefix
     draw do
-      scope as: 'foo' do
+      scope as: "foo" do
         resources :posts do
           resources :comments, shallow: true
         end
       end
     end
 
-    assert_equal '/comments/1', foo_comment_path('1')
+    assert_equal "/comments/1", foo_comment_path("1")
   end
 
   def test_scope_shallow_prefix_is_not_overwritten_by_as
     draw do
-      scope as: 'foo', shallow_prefix: 'bar' do
+      scope as: "foo", shallow_prefix: "bar" do
         resources :posts do
           resources :comments, shallow: true
         end
       end
     end
 
-    assert_equal '/comments/1', bar_comment_path('1')
+    assert_equal "/comments/1", bar_comment_path("1")
   end
 
   def test_scope_shallow_path_is_not_overwritten_by_path
     draw do
-      scope path: 'foo', shallow_path: 'bar' do
+      scope path: "foo", shallow_path: "bar" do
         resources :posts do
           resources :comments, shallow: true
         end
       end
     end
 
-    assert_equal '/bar/comments/1', comment_path('1')
+    assert_equal "/bar/comments/1", comment_path("1")
   end
 
   def test_resource_where_as_is_empty
     draw do
-      resource :post, as: ''
+      resource :post, as: ""
 
-      scope 'post', as: 'post' do
-        resource :comment, as: ''
+      scope "post", as: "post" do
+        resource :comment, as: ""
       end
     end
 
-    assert_equal '/post/new', new_path
-    assert_equal '/post/comment/new', new_post_path
+    assert_equal "/post/new", new_path
+    assert_equal "/post/comment/new", new_post_path
   end
 
   def test_resources_where_as_is_empty
     draw do
-      resources :posts, as: ''
+      resources :posts, as: ""
 
-      scope 'posts', as: 'posts' do
-        resources :comments, as: ''
+      scope "posts", as: "posts" do
+        resources :comments, as: ""
       end
     end
 
-    assert_equal '/posts/new', new_path
-    assert_equal '/posts/comments/new', new_posts_path
+    assert_equal "/posts/new", new_path
+    assert_equal "/posts/comments/new", new_posts_path
   end
 
   def test_scope_where_as_is_empty
     draw do
-      scope 'post', as: '' do
+      scope "post", as: "" do
         resource :user
         resources :comments
       end
     end
 
-    assert_equal '/post/user/new', new_user_path
-    assert_equal '/post/comments/new', new_comment_path
+    assert_equal "/post/user/new", new_user_path
+    assert_equal "/post/comments/new", new_comment_path
   end
 
   def test_head_fetch_with_mount_on_root
     draw do
-      get '/home' => 'test#index'
-      mount lambda { |env| [200, {}, [env['REQUEST_METHOD']]] }, at: '/'
+      get "/home" => "test#index"
+      mount lambda { |env| [200, {}, [env["REQUEST_METHOD"]]] }, at: "/"
     end
 
     # HEAD request should match `get /home` rather than the
     # lower-precedence Rack app mounted at `/`.
-    head '/home'
+    head "/home"
     assert_response :ok
-    assert_equal 'test#index', @response.body
+    assert_equal "test#index", @response.body
 
     # But the Rack app can still respond to its own HEAD requests.
-    head '/foobar'
+    head "/foobar"
     assert_response :ok
-    assert_equal 'HEAD', @response.body
+    assert_equal "HEAD", @response.body
   end
 
   def test_passing_action_parameters_to_url_helpers_raises_error_if_parameters_are_not_permitted
     draw do
-      root :to => 'projects#index'
+      root to: "projects#index"
     end
-    params = ActionController::Parameters.new(id: '1')
+    params = ActionController::Parameters.new(id: "1")
 
-    assert_raises ArgumentError do
+    assert_raises ActionController::UnfilteredParameters do
       root_path(params)
     end
   end
 
   def test_passing_action_parameters_to_url_helpers_is_allowed_if_parameters_are_permitted
     draw do
-      root :to => 'projects#index'
+      root to: "projects#index"
     end
-    params = ActionController::Parameters.new(id: '1')
+    params = ActionController::Parameters.new(id: "1")
     params.permit!
 
-    assert_equal '/?id=1', root_path(params)
+    assert_equal "/?id=1", root_path(params)
   end
 
   def test_dynamic_controller_segments_are_deprecated
     assert_deprecated do
       draw do
-        get '/:controller', action: 'index'
+        get "/:controller", action: "index"
       end
     end
   end
@@ -3621,16 +3662,76 @@ class TestRoutingMapper < ActionDispatch::IntegrationTest
   def test_dynamic_action_segments_are_deprecated
     assert_deprecated do
       draw do
-        get '/pages/:action', controller: 'pages'
+        get "/pages/:action", controller: "pages"
+      end
+    end
+  end
+
+  def test_multiple_roots
+    draw do
+      namespace :foo do
+        root "pages#index", constraints: { host: "www.example.com" }
+        root "admin/pages#index", constraints: { host: "admin.example.com" }
+      end
+
+      root "pages#index", constraints: { host: "www.example.com" }
+      root "admin/pages#index", constraints: { host: "admin.example.com" }
+    end
+
+    get "http://www.example.com/foo"
+    assert_equal "foo/pages#index", @response.body
+
+    get "http://admin.example.com/foo"
+    assert_equal "foo/admin/pages#index", @response.body
+
+    get "http://www.example.com/"
+    assert_equal "pages#index", @response.body
+
+    get "http://admin.example.com/"
+    assert_equal "admin/pages#index", @response.body
+  end
+
+  def test_multiple_namespaced_roots
+    draw do
+      namespace :foo do
+        root "test#index"
+      end
+
+      root "test#index"
+
+      namespace :bar do
+        root "test#index"
       end
     end
+
+    assert_equal "/foo", foo_root_path
+    assert_equal "/", root_path
+    assert_equal "/bar", bar_root_path
+  end
+
+  def test_nested_routes_under_format_resource
+    draw do
+      resources :formats do
+        resources :items
+      end
+    end
+
+    get "/formats/1/items.json"
+    assert_equal 200, @response.status
+    assert_equal "items#index", @response.body
+    assert_equal "/formats/1/items.json", format_items_path(1, :json)
+
+    get "/formats/1/items/2.json"
+    assert_equal 200, @response.status
+    assert_equal "items#show", @response.body
+    assert_equal "/formats/1/items/2.json", format_item_path(1, 2, :json)
   end
 
 private
 
   def draw(&block)
     self.class.stub_controllers do |routes|
-      routes.default_url_options = { host: 'www.example.com' }
+      routes.default_url_options = { host: "www.example.com" }
       routes.draw(&block)
       @app = RoutedRackApp.new routes
     end
@@ -3656,9 +3757,9 @@ private
     https!(old_https)
   end
 
-  def verify_redirect(url, status=301)
+  def verify_redirect(url, status = 301)
     assert_equal status, @response.status
-    assert_equal url, @response.headers['Location']
+    assert_equal url, @response.headers["Location"]
     assert_equal expected_redirect_body(url), @response.body
   end
 
@@ -3695,13 +3796,13 @@ class TestAltApp < ActionDispatch::IntegrationTest
 
   class XHeader
     def call(env)
-      [200, {"Content-Type" => "text/html"}, ["XHeader"]]
+      [200, { "Content-Type" => "text/html" }, ["XHeader"]]
     end
   end
 
   class AltApp
     def call(env)
-      [200, {"Content-Type" => "text/html"}, ["Alternative App"]]
+      [200, { "Content-Type" => "text/html" }, ["Alternative App"]]
     end
   end
 
@@ -3711,7 +3812,7 @@ class TestAltApp < ActionDispatch::IntegrationTest
     end
   }.new
   AltRoutes.draw do
-    get "/" => TestAltApp::XHeader.new, :constraints => {:x_header => /HEADER/}
+    get "/" => TestAltApp::XHeader.new, :constraints => { x_header: /HEADER/ }
     get "/" => TestAltApp::AltApp.new
   end
 
@@ -3739,7 +3840,7 @@ end
 
 class TestAppendingRoutes < ActionDispatch::IntegrationTest
   def simple_app(resp)
-    lambda { |e| [ 200, { 'Content-Type' => 'text/plain' }, [resp] ] }
+    lambda { |e| [ 200, { "Content-Type" => "text/plain" }, [resp] ] }
   end
 
   def setup
@@ -3747,28 +3848,28 @@ class TestAppendingRoutes < ActionDispatch::IntegrationTest
     s = self
     routes = ActionDispatch::Routing::RouteSet.new
     routes.append do
-      get '/hello'   => s.simple_app('fail')
-      get '/goodbye' => s.simple_app('goodbye')
+      get "/hello"   => s.simple_app("fail")
+      get "/goodbye" => s.simple_app("goodbye")
     end
 
     routes.draw do
-      get '/hello' => s.simple_app('hello')
+      get "/hello" => s.simple_app("hello")
     end
     @app = self.class.build_app routes
   end
 
   def test_goodbye_should_be_available
-    get '/goodbye'
-    assert_equal 'goodbye', @response.body
+    get "/goodbye"
+    assert_equal "goodbye", @response.body
   end
 
   def test_hello_should_not_be_overwritten
-    get '/hello'
-    assert_equal 'hello', @response.body
+    get "/hello"
+    assert_equal "hello", @response.body
   end
 
   def test_missing_routes_are_still_missing
-    get '/random'
+    get "/random"
     assert_equal 404, @response.status
   end
 end
@@ -3791,7 +3892,7 @@ class TestNamespaceWithControllerOption < ActionDispatch::IntegrationTest
   def test_missing_controller
     ex = assert_raises(ArgumentError) {
       draw do
-        get '/foo/bar', :action => :index
+        get "/foo/bar", action: :index
       end
     }
     assert_match(/Missing :controller/, ex.message)
@@ -3800,7 +3901,7 @@ class TestNamespaceWithControllerOption < ActionDispatch::IntegrationTest
   def test_missing_controller_with_to
     ex = assert_raises(ArgumentError) {
       draw do
-        get '/foo/bar', :to => 'foo'
+        get "/foo/bar", to: "foo"
       end
     }
     assert_match(/Missing :controller/, ex.message)
@@ -3809,7 +3910,7 @@ class TestNamespaceWithControllerOption < ActionDispatch::IntegrationTest
   def test_missing_action_on_hash
     ex = assert_raises(ArgumentError) {
       draw do
-        get '/foo/bar', :to => 'foo#'
+        get "/foo/bar", to: "foo#"
       end
     }
     assert_match(/Missing :action/, ex.message)
@@ -3818,20 +3919,20 @@ class TestNamespaceWithControllerOption < ActionDispatch::IntegrationTest
   def test_valid_controller_options_inside_namespace
     draw do
       namespace :admin do
-        resources :storage_files, :controller => "storage_files"
+        resources :storage_files, controller: "storage_files"
       end
     end
 
-    get '/admin/storage_files'
+    get "/admin/storage_files"
     assert_equal "admin/storage_files#index", @response.body
   end
 
   def test_resources_with_valid_namespaced_controller_option
     draw do
-      resources :storage_files, :controller => 'admin/storage_files'
+      resources :storage_files, controller: "admin/storage_files"
     end
 
-    get '/storage_files'
+    get "/storage_files"
     assert_equal "admin/storage_files#index", @response.body
   end
 
@@ -3839,7 +3940,7 @@ class TestNamespaceWithControllerOption < ActionDispatch::IntegrationTest
     e = assert_raise(ArgumentError) do
       draw do
         namespace :admin do
-          resources :storage_files, :controller => "StorageFiles"
+          resources :storage_files, controller: "StorageFiles"
         end
       end
     end
@@ -3850,7 +3951,7 @@ class TestNamespaceWithControllerOption < ActionDispatch::IntegrationTest
   def test_warn_with_ruby_constant_syntax_namespaced_controller_option
     e = assert_raise(ArgumentError) do
       draw do
-        resources :storage_files, :controller => 'Admin::StorageFiles'
+        resources :storage_files, controller: "Admin::StorageFiles"
       end
     end
 
@@ -3860,7 +3961,7 @@ class TestNamespaceWithControllerOption < ActionDispatch::IntegrationTest
   def test_warn_with_ruby_constant_syntax_no_colons
     e = assert_raise(ArgumentError) do
       draw do
-        resources :storage_files, :controller => 'Admin'
+        resources :storage_files, controller: "Admin"
       end
     end
 
@@ -3878,7 +3979,7 @@ class TestDefaultScope < ActionDispatch::IntegrationTest
   end
 
   DefaultScopeRoutes = ActionDispatch::Routing::RouteSet.new
-  DefaultScopeRoutes.default_scope = {:module => :blog}
+  DefaultScopeRoutes.default_scope = { module: :blog }
   DefaultScopeRoutes.draw do
     resources :posts
   end
@@ -3892,7 +3993,7 @@ class TestDefaultScope < ActionDispatch::IntegrationTest
   include DefaultScopeRoutes.url_helpers
 
   def test_default_scope
-    get '/posts'
+    get "/posts"
     assert_equal "blog/posts#index", @response.body
   end
 end
@@ -3908,7 +4009,7 @@ class TestHttpMethods < ActionDispatch::IntegrationTest
   RFC5789 = %w(PATCH)
 
   def simple_app(response)
-    lambda { |env| [ 200, { 'Content-Type' => 'text/plain' }, [response] ] }
+    lambda { |env| [ 200, { "Content-Type" => "text/plain" }, [response] ] }
   end
 
   attr_reader :app
@@ -3920,14 +4021,14 @@ class TestHttpMethods < ActionDispatch::IntegrationTest
 
     routes.draw do
       (RFC2616 + RFC2518 + RFC3253 + RFC3648 + RFC3744 + RFC5323 + RFC4791 + RFC5789).each do |method|
-        match '/' => s.simple_app(method), :via => method.underscore.to_sym
+        match "/" => s.simple_app(method), :via => method.underscore.to_sym
       end
     end
   end
 
   (RFC2616 + RFC2518 + RFC3253 + RFC3648 + RFC3744 + RFC5323 + RFC4791 + RFC5789).each do |method|
     test "request method #{method.underscore} can be matched" do
-      get '/', headers: { 'REQUEST_METHOD' => method }
+      get "/", headers: { "REQUEST_METHOD" => method }
       assert_equal method, @response.body
     end
   end
@@ -3936,14 +4037,14 @@ end
 class TestUriPathEscaping < ActionDispatch::IntegrationTest
   Routes = ActionDispatch::Routing::RouteSet.new.tap do |app|
     app.draw do
-      get '/:segment' => lambda { |env|
-        path_params = env['action_dispatch.request.path_parameters']
-        [200, { 'Content-Type' => 'text/plain' }, [path_params[:segment]]]
+      get "/:segment" => lambda { |env|
+        path_params = env["action_dispatch.request.path_parameters"]
+        [200, { "Content-Type" => "text/plain" }, [path_params[:segment]]]
       }, :as => :segment
 
-      get '/*splat' => lambda { |env|
-        path_params = env['action_dispatch.request.path_parameters']
-        [200, { 'Content-Type' => 'text/plain' }, [path_params[:splat]]]
+      get "/*splat" => lambda { |env|
+        path_params = env["action_dispatch.request.path_parameters"]
+        [200, { "Content-Type" => "text/plain" }, [path_params[:splat]]]
       }, :as => :splat
     end
   end
@@ -3952,22 +4053,22 @@ class TestUriPathEscaping < ActionDispatch::IntegrationTest
   APP = build_app Routes
   def app; APP end
 
-  test 'escapes slash in generated path segment' do
-    assert_equal '/a%20b%2Fc+d', segment_path(:segment => 'a b/c+d')
+  test "escapes slash in generated path segment" do
+    assert_equal "/a%20b%2Fc+d", segment_path(segment: "a b/c+d")
   end
 
-  test 'unescapes recognized path segment' do
-    get '/a%20b%2Fc+d'
-    assert_equal 'a b/c+d', @response.body
+  test "unescapes recognized path segment" do
+    get "/a%20b%2Fc+d"
+    assert_equal "a b/c+d", @response.body
   end
 
-  test 'does not escape slash in generated path splat' do
-    assert_equal '/a%20b/c+d', splat_path(:splat => 'a b/c+d')
+  test "does not escape slash in generated path splat" do
+    assert_equal "/a%20b/c+d", splat_path(splat: "a b/c+d")
   end
 
-  test 'unescapes recognized path splat' do
-    get '/a%20b/c+d'
-    assert_equal 'a b/c+d', @response.body
+  test "unescapes recognized path splat" do
+    get "/a%20b/c+d"
+    assert_equal "a b/c+d", @response.body
   end
 end
 
@@ -3975,7 +4076,7 @@ class TestUnicodePaths < ActionDispatch::IntegrationTest
   Routes = ActionDispatch::Routing::RouteSet.new.tap do |app|
     app.draw do
       get "/ほげ" => lambda { |env|
-        [200, { 'Content-Type' => 'text/plain' }, []]
+        [200, { "Content-Type" => "text/plain" }, []]
       }, :as => :unicode_path
     end
   end
@@ -3984,7 +4085,7 @@ class TestUnicodePaths < ActionDispatch::IntegrationTest
   APP = build_app Routes
   def app; APP end
 
-  test 'recognizes unicode path' do
+  test "recognizes unicode path" do
     get "/#{Rack::Utils.escape("ほげ")}"
     assert_equal "200", @response.code
   end
@@ -4008,7 +4109,7 @@ class TestMultipleNestedController < ActionDispatch::IntegrationTest
         include Routes.url_helpers
 
         def index
-          render :inline => "<%= url_for :controller => '/pooh', :action => 'index' %>"
+          render inline: "<%= url_for :controller => '/pooh', :action => 'index' %>"
         end
       end
     end
@@ -4026,7 +4127,7 @@ end
 class TestTildeAndMinusPaths < ActionDispatch::IntegrationTest
   Routes = ActionDispatch::Routing::RouteSet.new.tap do |app|
     app.draw do
-      ok = lambda { |env| [200, { 'Content-Type' => 'text/plain' }, []] }
+      ok = lambda { |env| [200, { "Content-Type" => "text/plain" }, []] }
 
       get "/~user" => ok
       get "/young-and-fine" => ok
@@ -4037,25 +4138,24 @@ class TestTildeAndMinusPaths < ActionDispatch::IntegrationTest
   APP = build_app Routes
   def app; APP end
 
-  test 'recognizes tilde path' do
+  test "recognizes tilde path" do
     get "/~user"
     assert_equal "200", @response.code
   end
 
-  test 'recognizes minus path' do
+  test "recognizes minus path" do
     get "/young-and-fine"
     assert_equal "200", @response.code
   end
-
 end
 
 class TestRedirectInterpolation < ActionDispatch::IntegrationTest
   Routes = ActionDispatch::Routing::RouteSet.new.tap do |app|
     app.draw do
-      ok = lambda { |env| [200, { 'Content-Type' => 'text/plain' }, []] }
+      ok = lambda { |env| [200, { "Content-Type" => "text/plain" }, []] }
 
       get "/foo/:id" => redirect("/foo/bar/%{id}")
-      get "/bar/:id" => redirect(:path => "/foo/bar/%{id}")
+      get "/bar/:id" => redirect(path: "/foo/bar/%{id}")
       get "/baz/:id" => redirect("/baz?id=%{id}&foo=?&bar=1#id-%{id}")
       get "/foo/bar/:id" => ok
       get "/baz" => ok
@@ -4084,9 +4184,9 @@ class TestRedirectInterpolation < ActionDispatch::IntegrationTest
   end
 
 private
-  def verify_redirect(url, status=301)
+  def verify_redirect(url, status = 301)
     assert_equal status, @response.status
-    assert_equal url, @response.headers['Location']
+    assert_equal url, @response.headers["Location"]
     assert_equal expected_redirect_body(url), @response.body
   end
 
@@ -4098,9 +4198,9 @@ end
 class TestConstraintsAccessingParameters < ActionDispatch::IntegrationTest
   Routes = ActionDispatch::Routing::RouteSet.new.tap do |app|
     app.draw do
-      ok = lambda { |env| [200, { 'Content-Type' => 'text/plain' }, []] }
+      ok = lambda { |env| [200, { "Content-Type" => "text/plain" }, []] }
 
-      get "/:foo" => ok, :constraints => lambda { |r| r.params[:foo] == 'foo' }
+      get "/:foo" => ok, :constraints => lambda { |r| r.params[:foo] == "foo" }
       get "/:bar" => ok
     end
   end
@@ -4110,7 +4210,7 @@ class TestConstraintsAccessingParameters < ActionDispatch::IntegrationTest
 
   test "parameters are reset between constraint checks" do
     get "/bar"
-    assert_equal nil, @request.params[:foo]
+    assert_nil @request.params[:foo]
     assert_equal "bar", @request.params[:bar]
   end
 end
@@ -4118,21 +4218,21 @@ end
 class TestGlobRoutingMapper < ActionDispatch::IntegrationTest
   Routes = ActionDispatch::Routing::RouteSet.new.tap do |app|
     app.draw do
-      ok = lambda { |env| [200, { 'Content-Type' => 'text/plain' }, []] }
+      ok = lambda { |env| [200, { "Content-Type" => "text/plain" }, []] }
 
-      get "/*id" => redirect("/not_cars"), :constraints => {id: /dummy/}
+      get "/*id" => redirect("/not_cars"), :constraints => { id: /dummy/ }
       get "/cars" => ok
     end
   end
 
-  #include Routes.url_helpers
+  # include Routes.url_helpers
   APP = build_app Routes
   def app; APP end
 
   def test_glob_constraint
     get "/dummy"
     assert_equal "301", @response.code
-    assert_equal "/not_cars", @response.header['Location'].match('/[^/]+$')[0]
+    assert_equal "/not_cars", @response.header["Location"].match("/[^/]+$")[0]
   end
 
   def test_glob_constraint_skip_route
@@ -4148,17 +4248,17 @@ end
 class TestOptimizedNamedRoutes < ActionDispatch::IntegrationTest
   Routes = ActionDispatch::Routing::RouteSet.new.tap do |app|
     app.draw do
-      ok = lambda { |env| [200, { 'Content-Type' => 'text/plain' }, []] }
-      get '/foo' => ok, as: :foo
+      ok = lambda { |env| [200, { "Content-Type" => "text/plain" }, []] }
+      get "/foo" => ok, as: :foo
 
       ActiveSupport::Deprecation.silence do
-        get '/post(/:action(/:id))' => ok, as: :posts
+        get "/post(/:action(/:id))" => ok, as: :posts
       end
 
-      get '/:foo/:foo_type/bars/:id' => ok, as: :bar
-      get '/projects/:id.:format' => ok, as: :project
-      get '/pages/:id' => ok, as: :page
-      get '/wiki/*page' => ok, as: :wiki
+      get "/:foo/:foo_type/bars/:id" => ok, as: :bar
+      get "/projects/:id.:format" => ok, as: :project
+      get "/pages/:id" => ok, as: :page
+      get "/wiki/*page" => ok, as: :wiki
     end
   end
 
@@ -4166,51 +4266,51 @@ class TestOptimizedNamedRoutes < ActionDispatch::IntegrationTest
   APP = build_app Routes
   def app; APP end
 
-  test 'enabled when not mounted and default_url_options is empty' do
+  test "enabled when not mounted and default_url_options is empty" do
     assert Routes.url_helpers.optimize_routes_generation?
   end
 
-  test 'named route called as singleton method' do
-    assert_equal '/foo', Routes.url_helpers.foo_path
+  test "named route called as singleton method" do
+    assert_equal "/foo", Routes.url_helpers.foo_path
   end
 
-  test 'named route called on included module' do
-    assert_equal '/foo', foo_path
+  test "named route called on included module" do
+    assert_equal "/foo", foo_path
   end
 
-  test 'nested optional segments are removed' do
-    assert_equal '/post', Routes.url_helpers.posts_path
-    assert_equal '/post', posts_path
+  test "nested optional segments are removed" do
+    assert_equal "/post", Routes.url_helpers.posts_path
+    assert_equal "/post", posts_path
   end
 
-  test 'segments with same prefix are replaced correctly' do
-    assert_equal '/foo/baz/bars/1', Routes.url_helpers.bar_path('foo', 'baz', '1')
-    assert_equal '/foo/baz/bars/1', bar_path('foo', 'baz', '1')
+  test "segments with same prefix are replaced correctly" do
+    assert_equal "/foo/baz/bars/1", Routes.url_helpers.bar_path("foo", "baz", "1")
+    assert_equal "/foo/baz/bars/1", bar_path("foo", "baz", "1")
   end
 
-  test 'segments separated with a period are replaced correctly' do
-    assert_equal '/projects/1.json', Routes.url_helpers.project_path(1, :json)
-    assert_equal '/projects/1.json', project_path(1, :json)
+  test "segments separated with a period are replaced correctly" do
+    assert_equal "/projects/1.json", Routes.url_helpers.project_path(1, :json)
+    assert_equal "/projects/1.json", project_path(1, :json)
   end
 
-  test 'segments with question marks are escaped' do
-    assert_equal '/pages/foo%3Fbar', Routes.url_helpers.page_path('foo?bar')
-    assert_equal '/pages/foo%3Fbar', page_path('foo?bar')
+  test "segments with question marks are escaped" do
+    assert_equal "/pages/foo%3Fbar", Routes.url_helpers.page_path("foo?bar")
+    assert_equal "/pages/foo%3Fbar", page_path("foo?bar")
   end
 
-  test 'segments with slashes are escaped' do
-    assert_equal '/pages/foo%2Fbar', Routes.url_helpers.page_path('foo/bar')
-    assert_equal '/pages/foo%2Fbar', page_path('foo/bar')
+  test "segments with slashes are escaped" do
+    assert_equal "/pages/foo%2Fbar", Routes.url_helpers.page_path("foo/bar")
+    assert_equal "/pages/foo%2Fbar", page_path("foo/bar")
   end
 
-  test 'glob segments with question marks are escaped' do
-    assert_equal '/wiki/foo%3Fbar', Routes.url_helpers.wiki_path('foo?bar')
-    assert_equal '/wiki/foo%3Fbar', wiki_path('foo?bar')
+  test "glob segments with question marks are escaped" do
+    assert_equal "/wiki/foo%3Fbar", Routes.url_helpers.wiki_path("foo?bar")
+    assert_equal "/wiki/foo%3Fbar", wiki_path("foo?bar")
   end
 
-  test 'glob segments with slashes are not escaped' do
-    assert_equal '/wiki/foo/bar', Routes.url_helpers.wiki_path('foo/bar')
-    assert_equal '/wiki/foo/bar', wiki_path('foo/bar')
+  test "glob segments with slashes are not escaped" do
+    assert_equal "/wiki/foo/bar", Routes.url_helpers.wiki_path("foo/bar")
+    assert_equal "/wiki/foo/bar", wiki_path("foo/bar")
   end
 end
 
@@ -4229,9 +4329,9 @@ class TestNamedRouteUrlHelpers < ActionDispatch::IntegrationTest
 
   Routes = ActionDispatch::Routing::RouteSet.new.tap do |app|
     app.draw do
-      scope :module => "test_named_route_url_helpers" do
-        get "/categories/:id" => 'categories#show', :as => :category
-        get "/products/:id" => 'products#show', :as => :product
+      scope module: "test_named_route_url_helpers" do
+        get "/categories/:id" => "categories#show", :as => :category
+        get "/products/:id" => "products#show", :as => :product
       end
     end
   end
@@ -4253,21 +4353,21 @@ end
 class TestUrlConstraints < ActionDispatch::IntegrationTest
   Routes = ActionDispatch::Routing::RouteSet.new.tap do |app|
     app.draw do
-      ok = lambda { |env| [200, { 'Content-Type' => 'text/plain' }, []] }
+      ok = lambda { |env| [200, { "Content-Type" => "text/plain" }, []] }
 
-      constraints :subdomain => 'admin' do
-        get '/' => ok, :as => :admin_root
+      constraints subdomain: "admin" do
+        get "/" => ok, :as => :admin_root
       end
 
-      scope :constraints => { :protocol => 'https://' } do
-        get '/' => ok, :as => :secure_root
+      scope constraints: { protocol: "https://" } do
+        get "/" => ok, :as => :secure_root
       end
 
-      get '/' => ok, :as => :alternate_root, :constraints => { :port => 8080 }
+      get "/" => ok, :as => :alternate_root, :constraints => { port: 8080 }
 
-      get '/search' => ok, :constraints => { :subdomain => false }
+      get "/search" => ok, :constraints => { subdomain: false }
 
-      get '/logs' => ok, :constraints => { :subdomain => true }
+      get "/logs" => ok, :constraints => { subdomain: true }
     end
   end
 
@@ -4276,63 +4376,66 @@ class TestUrlConstraints < ActionDispatch::IntegrationTest
   def app; APP end
 
   test "constraints are copied to defaults when using constraints method" do
-    assert_equal 'http://admin.example.com/', admin_root_url
+    assert_equal "http://admin.example.com/", admin_root_url
 
-    get 'http://admin.example.com/'
+    get "http://admin.example.com/"
     assert_response :success
   end
 
   test "constraints are copied to defaults when using scope constraints hash" do
-    assert_equal 'https://www.example.com/', secure_root_url
+    assert_equal "https://www.example.com/", secure_root_url
 
-    get 'https://www.example.com/'
+    get "https://www.example.com/"
     assert_response :success
   end
 
   test "constraints are copied to defaults when using route constraints hash" do
-    assert_equal 'http://www.example.com:8080/', alternate_root_url
+    assert_equal "http://www.example.com:8080/", alternate_root_url
 
-    get 'http://www.example.com:8080/'
+    get "http://www.example.com:8080/"
     assert_response :success
   end
 
   test "false constraint expressions check for absence of values" do
-    get 'http://example.com/search'
+    get "http://example.com/search"
     assert_response :success
-    assert_equal 'http://example.com/search', search_url
+    assert_equal "http://example.com/search", search_url
 
-    get 'http://api.example.com/search'
+    get "http://api.example.com/search"
     assert_response :not_found
   end
 
   test "true constraint expressions check for presence of values" do
-    get 'http://api.example.com/logs'
+    get "http://api.example.com/logs"
     assert_response :success
-    assert_equal 'http://api.example.com/logs', logs_url
+    assert_equal "http://api.example.com/logs", logs_url
 
-    get 'http://example.com/logs'
+    get "http://example.com/logs"
     assert_response :not_found
   end
 end
 
 class TestInvalidUrls < ActionDispatch::IntegrationTest
   class FooController < ActionController::Base
+    def self.binary_params_for?(action)
+      action == "show"
+    end
+
     def show
       render plain: "foo#show"
     end
   end
 
-  test "invalid UTF-8 encoding returns a 400 Bad Request" do
+  test "invalid UTF-8 encoding returns a bad request" do
     with_routing do |set|
-      ActiveSupport::Deprecation.silence do
-        set.draw do
-          get "/bar/:id", :to => redirect("/foo/show/%{id}")
-          get "/foo/show(/:id)", :to => "test_invalid_urls/foo#show"
+      set.draw do
+        get "/bar/:id", to: redirect("/foo/show/%{id}")
 
-          ActiveSupport::Deprecation.silence do
-            get "/foo(/:action(/:id))", :controller => "test_invalid_urls/foo"
-            get "/:controller(/:action(/:id))"
-          end
+        ok = lambda { |env| [200, { "Content-Type" => "text/plain" }, []] }
+        get "/foobar/:id", to: ok
+
+        ActiveSupport::Deprecation.silence do
+          get "/:controller(/:action(/:id))"
         end
       end
 
@@ -4342,20 +4445,31 @@ class TestInvalidUrls < ActionDispatch::IntegrationTest
       get "/foo/%E2%EF%BF%BD%A6"
       assert_response :bad_request
 
-      get "/foo/show/%E2%EF%BF%BD%A6"
+      get "/bar/%E2%EF%BF%BD%A6"
       assert_response :bad_request
 
-      get "/bar/%E2%EF%BF%BD%A6"
+      get "/foobar/%E2%EF%BF%BD%A6"
       assert_response :bad_request
     end
   end
+
+  test "params encoded with binary_params_for? are treated as ASCII 8bit" do
+    with_routing do |set|
+      set.draw do
+        get "/foo/show(/:id)", to: "test_invalid_urls/foo#show"
+      end
+
+      get "/foo/show/%E2%EF%BF%BD%A6"
+      assert_response :ok
+    end
+  end
 end
 
 class TestOptionalRootSegments < ActionDispatch::IntegrationTest
   stub_controllers do |routes|
     Routes = routes
     Routes.draw do
-      get '/(page/:page)', :to => 'pages#index', :as => :root
+      get "/(page/:page)", to: "pages#index", as: :root
     end
   end
 
@@ -4367,27 +4481,27 @@ class TestOptionalRootSegments < ActionDispatch::IntegrationTest
   include Routes.url_helpers
 
   def test_optional_root_segments
-    get '/'
-    assert_equal 'pages#index', @response.body
-    assert_equal '/', root_path
+    get "/"
+    assert_equal "pages#index", @response.body
+    assert_equal "/", root_path
 
-    get '/page/1'
-    assert_equal 'pages#index', @response.body
-    assert_equal '1', @request.params[:page]
-    assert_equal '/page/1', root_path('1')
-    assert_equal '/page/1', root_path(:page => '1')
+    get "/page/1"
+    assert_equal "pages#index", @response.body
+    assert_equal "1", @request.params[:page]
+    assert_equal "/page/1", root_path("1")
+    assert_equal "/page/1", root_path(page: "1")
   end
 end
 
 class TestPortConstraints < ActionDispatch::IntegrationTest
   Routes = ActionDispatch::Routing::RouteSet.new.tap do |app|
     app.draw do
-      ok = lambda { |env| [200, { 'Content-Type' => 'text/plain' }, []] }
+      ok = lambda { |env| [200, { "Content-Type" => "text/plain" }, []] }
 
-      get '/integer', to: ok, constraints: { :port =>  8080  }
-      get '/string',  to: ok, constraints: { :port => '8080' }
-      get '/array',   to: ok, constraints: { :port => [8080] }
-      get '/regexp',  to: ok, constraints: { :port => /8080/ }
+      get "/integer", to: ok, constraints: { port: 8080  }
+      get "/string",  to: ok, constraints: { port: "8080" }
+      get "/array",   to: ok, constraints: { port: [8080] }
+      get "/regexp",  to: ok, constraints: { port: /8080/ }
     end
   end
 
@@ -4396,34 +4510,34 @@ class TestPortConstraints < ActionDispatch::IntegrationTest
   def app; APP end
 
   def test_integer_port_constraints
-    get 'http://www.example.com/integer'
+    get "http://www.example.com/integer"
     assert_response :not_found
 
-    get 'http://www.example.com:8080/integer'
+    get "http://www.example.com:8080/integer"
     assert_response :success
   end
 
   def test_string_port_constraints
-    get 'http://www.example.com/string'
+    get "http://www.example.com/string"
     assert_response :not_found
 
-    get 'http://www.example.com:8080/string'
+    get "http://www.example.com:8080/string"
     assert_response :success
   end
 
   def test_array_port_constraints
-    get 'http://www.example.com/array'
+    get "http://www.example.com/array"
     assert_response :not_found
 
-    get 'http://www.example.com:8080/array'
+    get "http://www.example.com:8080/array"
     assert_response :success
   end
 
   def test_regexp_port_constraints
-    get 'http://www.example.com/regexp'
+    get "http://www.example.com/regexp"
     assert_response :not_found
 
-    get 'http://www.example.com:8080/regexp'
+    get "http://www.example.com:8080/regexp"
     assert_response :success
   end
 end
@@ -4431,12 +4545,12 @@ end
 class TestFormatConstraints < ActionDispatch::IntegrationTest
   Routes = ActionDispatch::Routing::RouteSet.new.tap do |app|
     app.draw do
-      ok = lambda { |env| [200, { 'Content-Type' => 'text/plain' }, []] }
+      ok = lambda { |env| [200, { "Content-Type" => "text/plain" }, []] }
 
-      get '/string', to: ok, constraints: { format: 'json'  }
-      get '/regexp',  to: ok, constraints: { format: /json/ }
-      get '/json_only', to: ok, format: true, constraints: { format: /json/ }
-      get '/xml_only', to: ok, format: 'xml'
+      get "/string", to: ok, constraints: { format: "json"  }
+      get "/regexp",  to: ok, constraints: { format: /json/ }
+      get "/json_only", to: ok, format: true, constraints: { format: /json/ }
+      get "/xml_only", to: ok, format: "xml"
     end
   end
 
@@ -4445,46 +4559,46 @@ class TestFormatConstraints < ActionDispatch::IntegrationTest
   def app; APP end
 
   def test_string_format_constraints
-    get 'http://www.example.com/string'
+    get "http://www.example.com/string"
     assert_response :success
 
-    get 'http://www.example.com/string.json'
+    get "http://www.example.com/string.json"
     assert_response :success
 
-    get 'http://www.example.com/string.html'
+    get "http://www.example.com/string.html"
     assert_response :not_found
   end
 
   def test_regexp_format_constraints
-    get 'http://www.example.com/regexp'
+    get "http://www.example.com/regexp"
     assert_response :success
 
-    get 'http://www.example.com/regexp.json'
+    get "http://www.example.com/regexp.json"
     assert_response :success
 
-    get 'http://www.example.com/regexp.html'
+    get "http://www.example.com/regexp.html"
     assert_response :not_found
   end
 
   def test_enforce_with_format_true_with_constraint
-    get 'http://www.example.com/json_only.json'
+    get "http://www.example.com/json_only.json"
     assert_response :success
 
-    get 'http://www.example.com/json_only.html'
+    get "http://www.example.com/json_only.html"
     assert_response :not_found
 
-    get 'http://www.example.com/json_only'
+    get "http://www.example.com/json_only"
     assert_response :not_found
   end
 
   def test_enforce_with_string
-    get 'http://www.example.com/xml_only.xml'
+    get "http://www.example.com/xml_only.xml"
     assert_response :success
 
-    get 'http://www.example.com/xml_only'
+    get "http://www.example.com/xml_only"
     assert_response :success
 
-    get 'http://www.example.com/xml_only.json'
+    get "http://www.example.com/xml_only.json"
     assert_response :not_found
   end
 end
@@ -4493,8 +4607,8 @@ class TestCallableConstraintValidation < ActionDispatch::IntegrationTest
   def test_constraint_with_object_not_callable
     assert_raises(ArgumentError) do
       ActionDispatch::Routing::RouteSet.new.draw do
-        ok = lambda { |env| [200, { 'Content-Type' => 'text/plain' }, []] }
-        get '/test', to: ok, constraints: Object.new
+        ok = lambda { |env| [200, { "Content-Type" => "text/plain" }, []] }
+        get "/test", to: ok, constraints: Object.new
       end
     end
   end
@@ -4504,8 +4618,8 @@ class TestRouteDefaults < ActionDispatch::IntegrationTest
   stub_controllers do |routes|
     Routes = routes
     Routes.draw do
-      resources :posts, bucket_type: 'post'
-      resources :projects, defaults: { bucket_type: 'project' }
+      resources :posts, bucket_type: "post"
+      resources :projects, defaults: { bucket_type: "project" }
     end
   end
 
@@ -4518,14 +4632,14 @@ class TestRouteDefaults < ActionDispatch::IntegrationTest
 
   def test_route_options_are_required_for_url_for
     assert_raises(ActionController::UrlGenerationError) do
-      assert_equal '/posts/1', url_for(controller: 'posts', action: 'show', id: 1, only_path: true)
+      assert_equal "/posts/1", url_for(controller: "posts", action: "show", id: 1, only_path: true)
     end
 
-    assert_equal '/posts/1', url_for(controller: 'posts', action: 'show', id: 1, bucket_type: 'post', only_path: true)
+    assert_equal "/posts/1", url_for(controller: "posts", action: "show", id: 1, bucket_type: "post", only_path: true)
   end
 
   def test_route_defaults_are_not_required_for_url_for
-    assert_equal '/projects/1', url_for(controller: 'projects', action: 'show', id: 1, only_path: true)
+    assert_equal "/projects/1", url_for(controller: "projects", action: "show", id: 1, only_path: true)
   end
 end
 
@@ -4533,9 +4647,9 @@ class TestRackAppRouteGeneration < ActionDispatch::IntegrationTest
   stub_controllers do |routes|
     Routes = routes
     Routes.draw do
-      rack_app = lambda { |env| [200, { 'Content-Type' => 'text/plain' }, []] }
-      mount rack_app, at: '/account', as: 'account'
-      mount rack_app, at: '/:locale/account', as: 'localized_account'
+      rack_app = lambda { |env| [200, { "Content-Type" => "text/plain" }, []] }
+      mount rack_app, at: "/account", as: "account"
+      mount rack_app, at: "/:locale/account", as: "localized_account"
     end
   end
 
@@ -4548,11 +4662,11 @@ class TestRackAppRouteGeneration < ActionDispatch::IntegrationTest
 
   def test_mounted_application_doesnt_match_unnamed_route
     assert_raise(ActionController::UrlGenerationError) do
-      assert_equal '/account?controller=products', url_for(controller: 'products', action: 'index', only_path: true)
+      assert_equal "/account?controller=products", url_for(controller: "products", action: "index", only_path: true)
     end
 
     assert_raise(ActionController::UrlGenerationError) do
-      assert_equal '/de/account?controller=products', url_for(controller: 'products', action: 'index', :locale => 'de', only_path: true)
+      assert_equal "/de/account?controller=products", url_for(controller: "products", action: "index", locale: "de", only_path: true)
     end
   end
 end
@@ -4561,8 +4675,8 @@ class TestRedirectRouteGeneration < ActionDispatch::IntegrationTest
   stub_controllers do |routes|
     Routes = routes
     Routes.draw do
-      get '/account', to: redirect('/myaccount'), as: 'account'
-      get '/:locale/account', to: redirect('/%{locale}/myaccount'), as: 'localized_account'
+      get "/account", to: redirect("/myaccount"), as: "account"
+      get "/:locale/account", to: redirect("/%{locale}/myaccount"), as: "localized_account"
     end
   end
 
@@ -4575,11 +4689,11 @@ class TestRedirectRouteGeneration < ActionDispatch::IntegrationTest
 
   def test_redirect_doesnt_match_unnamed_route
     assert_raise(ActionController::UrlGenerationError) do
-      assert_equal '/account?controller=products', url_for(controller: 'products', action: 'index', only_path: true)
+      assert_equal "/account?controller=products", url_for(controller: "products", action: "index", only_path: true)
     end
 
     assert_raise(ActionController::UrlGenerationError) do
-      assert_equal '/de/account?controller=products', url_for(controller: 'products', action: 'index', :locale => 'de', only_path: true)
+      assert_equal "/de/account?controller=products", url_for(controller: "products", action: "index", locale: "de", only_path: true)
     end
   end
 end
@@ -4587,7 +4701,7 @@ end
 class TestUrlGenerationErrors < ActionDispatch::IntegrationTest
   Routes = ActionDispatch::Routing::RouteSet.new.tap do |app|
     app.draw do
-      get "/products/:id" => 'products#show', :as => :product
+      get "/products/:id" => "products#show", :as => :product
     end
   end
 
@@ -4596,29 +4710,32 @@ class TestUrlGenerationErrors < ActionDispatch::IntegrationTest
 
   include Routes.url_helpers
 
-  test "url helpers raise a helpful error message when generation fails" do
-    url, missing = { action: 'show', controller: 'products', id: nil }, [:id]
-    message = "No route matches #{url.inspect} missing required keys: #{missing.inspect}"
+  test "url helpers raise a 'missing keys' error for a nil param with optimized helpers" do
+    url, missing = { action: "show", controller: "products", id: nil }, [:id]
+    message = "No route matches #{url.inspect}, missing required keys: #{missing.inspect}"
 
-    # Optimized url helper
-    error = assert_raises(ActionController::UrlGenerationError){ product_path(nil) }
+    error = assert_raises(ActionController::UrlGenerationError) { product_path(nil) }
     assert_equal message, error.message
+  end
 
-    # Non-optimized url helper
-    error = assert_raises(ActionController::UrlGenerationError, message){ product_path(id: nil) }
+  test "url helpers raise a 'constraint failure' error for a nil param with non-optimized helpers" do
+    url, missing = { action: "show", controller: "products", id: nil }, [:id]
+    message = "No route matches #{url.inspect}, possible unmatched constraints: #{missing.inspect}"
+
+    error = assert_raises(ActionController::UrlGenerationError, message) { product_path(id: nil) }
     assert_equal message, error.message
   end
 
-  test "url helpers raise message with mixed parameters when generation fails " do
-    url, missing = { action: 'show', controller: 'products', id: nil, "id"=>"url-tested"}, [:id]
-    message = "No route matches #{url.inspect} missing required keys: #{missing.inspect}"
+  test "url helpers raise message with mixed parameters when generation fails" do
+    url, missing = { action: "show", controller: "products", id: nil, "id" => "url-tested" }, [:id]
+    message = "No route matches #{url.inspect}, possible unmatched constraints: #{missing.inspect}"
 
     # Optimized url helper
-    error = assert_raises(ActionController::UrlGenerationError){ product_path(nil, 'id'=>'url-tested') }
+    error = assert_raises(ActionController::UrlGenerationError) { product_path(nil, "id" => "url-tested") }
     assert_equal message, error.message
 
     # Non-optimized url helper
-    error = assert_raises(ActionController::UrlGenerationError, message){ product_path(id: nil, 'id'=>'url-tested') }
+    error = assert_raises(ActionController::UrlGenerationError, message) { product_path(id: nil, "id" => "url-tested") }
     assert_equal message, error.message
   end
 end
@@ -4632,9 +4749,9 @@ class TestDefaultUrlOptions < ActionDispatch::IntegrationTest
 
   Routes = ActionDispatch::Routing::RouteSet.new
   Routes.draw do
-    default_url_options locale: 'en'
-    scope ':locale', format: false do
-      get '/posts/:year/:month/:day', to: 'posts#archive', as: 'archived_posts'
+    default_url_options locale: "en"
+    scope ":locale", format: false do
+      get "/posts/:year/:month/:day", to: "posts#archive", as: "archived_posts"
     end
   end
 
@@ -4647,7 +4764,7 @@ class TestDefaultUrlOptions < ActionDispatch::IntegrationTest
   include Routes.url_helpers
 
   def test_positional_args_with_format_false
-    assert_equal '/en/posts/2014/12/13', archived_posts_path(2014, 12, 13)
+    assert_equal "/en/posts/2014/12/13", archived_posts_path(2014, 12, 13)
   end
 end
 
@@ -4665,7 +4782,7 @@ class TestErrorsInController < ActionDispatch::IntegrationTest
   Routes = ActionDispatch::Routing::RouteSet.new
   Routes.draw do
     ActiveSupport::Deprecation.silence do
-      get '/:controller(/:action)'
+      get "/:controller(/:action)"
     end
   end
 
@@ -4676,20 +4793,20 @@ class TestErrorsInController < ActionDispatch::IntegrationTest
   end
 
   def test_legit_no_method_errors_are_not_caught
-    get '/posts/foo'
+    get "/posts/foo"
     assert_equal 500, response.status
   end
 
   def test_legit_name_errors_are_not_caught
-    get '/posts/bar'
+    get "/posts/bar"
     assert_equal 500, response.status
   end
 
   def test_legit_routing_not_found_responses
-    get '/posts/baz'
+    get "/posts/baz"
     assert_equal 404, response.status
 
-    get '/i_do_not_exist'
+    get "/i_do_not_exist"
     assert_equal 404, response.status
   end
 end
@@ -4697,17 +4814,17 @@ end
 class TestPartialDynamicPathSegments < ActionDispatch::IntegrationTest
   Routes = ActionDispatch::Routing::RouteSet.new
   Routes.draw do
-    ok = lambda { |env| [200, { 'Content-Type' => 'text/plain' }, []] }
+    ok = lambda { |env| [200, { "Content-Type" => "text/plain" }, []] }
 
-    get '/songs/song-:song', to: ok
-    get '/songs/:song-song', to: ok
-    get '/:artist/song-:song', to: ok
-    get '/:artist/:song-song', to: ok
+    get "/songs/song-:song", to: ok
+    get "/songs/:song-song", to: ok
+    get "/:artist/song-:song", to: ok
+    get "/:artist/:song-song", to: ok
 
-    get '/optional/songs(/song-:song)', to: ok
-    get '/optional/songs(/:song-song)', to: ok
-    get '/optional/:artist(/song-:song)', to: ok
-    get '/optional/:artist(/:song-song)', to: ok
+    get "/optional/songs(/song-:song)", to: ok
+    get "/optional/songs(/:song-song)", to: ok
+    get "/optional/:artist(/song-:song)", to: ok
+    get "/optional/:artist(/:song-song)", to: ok
   end
 
   APP = build_app Routes
@@ -4717,57 +4834,59 @@ class TestPartialDynamicPathSegments < ActionDispatch::IntegrationTest
   end
 
   def test_paths_with_partial_dynamic_segments_are_recognised
-    get '/david-bowie/changes-song'
+    get "/david-bowie/changes-song"
     assert_equal 200, response.status
-    assert_params artist: 'david-bowie', song: 'changes'
+    assert_params artist: "david-bowie", song: "changes"
 
-    get '/david-bowie/song-changes'
+    get "/david-bowie/song-changes"
     assert_equal 200, response.status
-    assert_params artist: 'david-bowie', song: 'changes'
+    assert_params artist: "david-bowie", song: "changes"
 
-    get '/songs/song-changes'
+    get "/songs/song-changes"
     assert_equal 200, response.status
-    assert_params song: 'changes'
+    assert_params song: "changes"
 
-    get '/songs/changes-song'
+    get "/songs/changes-song"
     assert_equal 200, response.status
-    assert_params song: 'changes'
+    assert_params song: "changes"
 
-    get '/optional/songs/song-changes'
+    get "/optional/songs/song-changes"
     assert_equal 200, response.status
-    assert_params song: 'changes'
+    assert_params song: "changes"
 
-    get '/optional/songs/changes-song'
+    get "/optional/songs/changes-song"
     assert_equal 200, response.status
-    assert_params song: 'changes'
+    assert_params song: "changes"
 
-    get '/optional/david-bowie/changes-song'
+    get "/optional/david-bowie/changes-song"
     assert_equal 200, response.status
-    assert_params artist: 'david-bowie', song: 'changes'
+    assert_params artist: "david-bowie", song: "changes"
 
-    get '/optional/david-bowie/song-changes'
+    get "/optional/david-bowie/song-changes"
     assert_equal 200, response.status
-    assert_params artist: 'david-bowie', song: 'changes'
+    assert_params artist: "david-bowie", song: "changes"
   end
 
   private
 
-  def assert_params(params)
-    assert_equal(params, request.path_parameters)
-  end
+    def assert_params(params)
+      assert_equal(params, request.path_parameters)
+    end
 end
 
 class TestPathParameters < ActionDispatch::IntegrationTest
   Routes = ActionDispatch::Routing::RouteSet.new.tap do |app|
     app.draw do
-      scope module: 'test_path_parameters' do
-        scope ':locale', locale: /en|ar/ do
-          root to: 'home#index'
-          get '/about', to: 'pages#about'
+      scope module: "test_path_parameters" do
+        scope ":locale", locale: /en|ar/ do
+          root to: "home#index"
+          get "/about", to: "pages#about"
         end
       end
 
-      get ':controller(/:action/(:id))'
+      ActiveSupport::Deprecation.silence do
+        get ":controller(/:action/(:id))"
+      end
     end
   end
 
@@ -4791,7 +4910,7 @@ class TestPathParameters < ActionDispatch::IntegrationTest
   def app; APP end
 
   def test_path_parameters_are_not_mutated
-    get '/en/about'
+    get "/en/about"
     assert_equal "/ar | /ar/about", @response.body
   end
 end
@@ -4799,7 +4918,7 @@ end
 class TestInternalRoutingParams < ActionDispatch::IntegrationTest
   Routes = ActionDispatch::Routing::RouteSet.new.tap do |app|
     app.draw do
-      get '/test_internal/:internal' => 'internal#internal'
+      get "/test_internal/:internal" => "internal#internal"
     end
   end
 
@@ -4816,12 +4935,162 @@ class TestInternalRoutingParams < ActionDispatch::IntegrationTest
   end
 
   def test_paths_with_partial_dynamic_segments_are_recognised
-    get '/test_internal/123'
+    get "/test_internal/123"
     assert_equal 200, response.status
 
     assert_equal(
-      { controller: 'internal', action: 'internal', internal: '123' },
+      { controller: "internal", action: "internal", internal: "123" },
       request.path_parameters
     )
   end
 end
+
+class FlashRedirectTest < ActionDispatch::IntegrationTest
+  SessionKey = "_myapp_session"
+  Generator  = ActiveSupport::LegacyKeyGenerator.new("b3c631c314c0bbca50c1b2843150fe33")
+  Rotations  = ActiveSupport::Messages::RotationConfiguration.new
+
+  class KeyGeneratorMiddleware
+    def initialize(app)
+      @app = app
+    end
+
+    def call(env)
+      env["action_dispatch.key_generator"] ||= Generator
+      env["action_dispatch.cookies_rotations"] ||= Rotations
+
+      @app.call(env)
+    end
+  end
+
+  class FooController < ActionController::Base
+    def bar
+      render plain: (flash[:foo] || "foo")
+    end
+  end
+
+  Routes = ActionDispatch::Routing::RouteSet.new
+  Routes.draw do
+    get "/foo", to: redirect { |params, req| req.flash[:foo] = "bar"; "/bar" }
+    get "/bar", to: "flash_redirect_test/foo#bar"
+  end
+
+  APP = build_app Routes do |middleware|
+    middleware.use KeyGeneratorMiddleware
+    middleware.use ActionDispatch::Session::CookieStore, key: SessionKey
+    middleware.use ActionDispatch::Flash
+    middleware.delete ActionDispatch::ShowExceptions
+  end
+
+  def app
+    APP
+  end
+
+  include Routes.url_helpers
+
+  def test_block_redirect_commits_flash
+    get "/foo", env: { "action_dispatch.key_generator" => Generator }
+    assert_response :redirect
+
+    follow_redirect!
+    assert_equal "bar", response.body
+  end
+end
+
+class TestRecognizePath < ActionDispatch::IntegrationTest
+  class PageConstraint
+    attr_reader :key, :pattern
+
+    def initialize(key, pattern)
+      @key = key
+      @pattern = pattern
+    end
+
+    def matches?(request)
+      request.path_parameters[key] =~ pattern
+    end
+  end
+
+  stub_controllers do |routes|
+    Routes = routes
+    routes.draw do
+      get "/hash/:foo", to: "pages#show", constraints: { foo: /foo/ }
+      get "/hash/:bar", to: "pages#show", constraints: { bar: /bar/ }
+
+      get "/proc/:foo", to: "pages#show", constraints: proc { |r| r.path_parameters[:foo] =~ /foo/ }
+      get "/proc/:bar", to: "pages#show", constraints: proc { |r| r.path_parameters[:bar] =~ /bar/ }
+
+      get "/class/:foo", to: "pages#show", constraints: PageConstraint.new(:foo, /foo/)
+      get "/class/:bar", to: "pages#show", constraints: PageConstraint.new(:bar, /bar/)
+    end
+  end
+
+  APP = build_app Routes
+  def app
+    APP
+  end
+
+  def test_hash_constraints_dont_leak_between_routes
+    expected_params = { controller: "pages", action: "show", bar: "bar" }
+    actual_params = recognize_path("/hash/bar")
+
+    assert_equal expected_params, actual_params
+  end
+
+  def test_proc_constraints_dont_leak_between_routes
+    expected_params = { controller: "pages", action: "show", bar: "bar" }
+    actual_params = recognize_path("/proc/bar")
+
+    assert_equal expected_params, actual_params
+  end
+
+  def test_class_constraints_dont_leak_between_routes
+    expected_params = { controller: "pages", action: "show", bar: "bar" }
+    actual_params = recognize_path("/class/bar")
+
+    assert_equal expected_params, actual_params
+  end
+
+  private
+
+    def recognize_path(*args)
+      Routes.recognize_path(*args)
+    end
+end
+
+class TestRelativeUrlRootGeneration < ActionDispatch::IntegrationTest
+  config = ActionDispatch::Routing::RouteSet::Config.new("/blog", false)
+
+  stub_controllers(config) do |routes|
+    Routes = routes
+
+    routes.draw do
+      get "/", to: "posts#index", as: :posts
+      get "/:id", to: "posts#show", as: :post
+    end
+  end
+
+  include Routes.url_helpers
+
+  APP = build_app Routes
+
+  def app
+    APP
+  end
+
+  def test_url_helpers
+    assert_equal "/blog/", posts_path({})
+    assert_equal "/blog/", Routes.url_helpers.posts_path({})
+
+    assert_equal "/blog/1", post_path(id: "1")
+    assert_equal "/blog/1", Routes.url_helpers.post_path(id: "1")
+  end
+
+  def test_optimized_url_helpers
+    assert_equal "/blog/", posts_path
+    assert_equal "/blog/", Routes.url_helpers.posts_path
+
+    assert_equal "/blog/1", post_path("1")
+    assert_equal "/blog/1", Routes.url_helpers.post_path("1")
+  end
+end
diff --git a/actionpack/test/dispatch/runner_test.rb b/actionpack/test/dispatch/runner_test.rb
new file mode 100644
index 0000000000..f16c7963af
--- /dev/null
+++ b/actionpack/test/dispatch/runner_test.rb
@@ -0,0 +1,19 @@
+# frozen_string_literal: true
+
+require "abstract_unit"
+
+class RunnerTest < ActiveSupport::TestCase
+  test "runner preserves the setting of integration_session" do
+    runner = Class.new do
+      def before_setup
+      end
+    end.new
+
+    runner.extend(ActionDispatch::Integration::Runner)
+    runner.integration_session.host! "lvh.me"
+
+    runner.before_setup
+
+    assert_equal "lvh.me", runner.integration_session.host
+  end
+end
diff --git a/actionpack/test/dispatch/session/abstract_store_test.rb b/actionpack/test/dispatch/session/abstract_store_test.rb
index d38d1bbce6..47616db15a 100644
--- a/actionpack/test/dispatch/session/abstract_store_test.rb
+++ b/actionpack/test/dispatch/session/abstract_store_test.rb
@@ -1,5 +1,7 @@
-require 'abstract_unit'
-require 'action_dispatch/middleware/session/abstract_store'
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "action_dispatch/middleware/session/abstract_store"
 
 module ActionDispatch
   module Session
@@ -37,7 +39,7 @@ module ActionDispatch
 
         assert @env
         session = Request::Session.find ActionDispatch::Request.new @env
-        session['foo'] = 'bar'
+        session["foo"] = "bar"
 
         as.call(@env)
         session1 = Request::Session.find ActionDispatch::Request.new @env
@@ -47,10 +49,10 @@ module ActionDispatch
       end
 
       private
-      def app(&block)
-        @env = nil
-        lambda { |env| @env = env }
-      end
+        def app(&block)
+          @env = nil
+          lambda { |env| @env = env }
+        end
     end
   end
 end
diff --git a/actionpack/test/dispatch/session/cache_store_test.rb b/actionpack/test/dispatch/session/cache_store_test.rb
index 769de1a1e0..06e67fac9f 100644
--- a/actionpack/test/dispatch/session/cache_store_test.rb
+++ b/actionpack/test/dispatch/session/cache_store_test.rb
@@ -1,5 +1,7 @@
-require 'abstract_unit'
-require 'fixtures/session_autoload_test/session_autoload_test/foo'
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "fixtures/session_autoload_test/session_autoload_test/foo"
 
 class CacheStoreTest < ActionDispatch::IntegrationTest
   class TestController < ActionController::Base
@@ -35,11 +37,11 @@ class CacheStoreTest < ActionDispatch::IntegrationTest
 
   def test_setting_and_getting_session_value
     with_test_route_set do
-      get '/set_session_value'
+      get "/set_session_value"
       assert_response :success
-      assert cookies['_session_id']
+      assert cookies["_session_id"]
 
-      get '/get_session_value'
+      get "/get_session_value"
       assert_response :success
       assert_equal 'foo: "bar"', response.body
     end
@@ -47,56 +49,56 @@ class CacheStoreTest < ActionDispatch::IntegrationTest
 
   def test_getting_nil_session_value
     with_test_route_set do
-      get '/get_session_value'
+      get "/get_session_value"
       assert_response :success
-      assert_equal 'foo: nil', response.body
+      assert_equal "foo: nil", response.body
     end
   end
 
   def test_getting_session_value_after_session_reset
     with_test_route_set do
-      get '/set_session_value'
+      get "/set_session_value"
       assert_response :success
-      assert cookies['_session_id']
-      session_cookie = cookies.send(:hash_for)['_session_id']
+      assert cookies["_session_id"]
+      session_cookie = cookies.send(:hash_for)["_session_id"]
 
-      get '/call_reset_session'
+      get "/call_reset_session"
       assert_response :success
-      assert_not_equal [], headers['Set-Cookie']
+      assert_not_equal [], headers["Set-Cookie"]
 
       cookies << session_cookie # replace our new session_id with our old, pre-reset session_id
 
-      get '/get_session_value'
+      get "/get_session_value"
       assert_response :success
-      assert_equal 'foo: nil', response.body, "data for this session should have been obliterated from cache"
+      assert_equal "foo: nil", response.body, "data for this session should have been obliterated from cache"
     end
   end
 
   def test_getting_from_nonexistent_session
     with_test_route_set do
-      get '/get_session_value'
+      get "/get_session_value"
       assert_response :success
-      assert_equal 'foo: nil', response.body
-      assert_nil cookies['_session_id'], "should only create session on write, not read"
+      assert_equal "foo: nil", response.body
+      assert_nil cookies["_session_id"], "should only create session on write, not read"
     end
   end
 
   def test_setting_session_value_after_session_reset
     with_test_route_set do
-      get '/set_session_value'
+      get "/set_session_value"
       assert_response :success
-      assert cookies['_session_id']
-      session_id = cookies['_session_id']
+      assert cookies["_session_id"]
+      session_id = cookies["_session_id"]
 
-      get '/call_reset_session'
+      get "/call_reset_session"
       assert_response :success
-      assert_not_equal [], headers['Set-Cookie']
+      assert_not_equal [], headers["Set-Cookie"]
 
-      get '/get_session_value'
+      get "/get_session_value"
       assert_response :success
-      assert_equal 'foo: nil', response.body
+      assert_equal "foo: nil", response.body
 
-      get '/get_session_id'
+      get "/get_session_id"
       assert_response :success
       assert_not_equal session_id, response.body
     end
@@ -104,12 +106,12 @@ class CacheStoreTest < ActionDispatch::IntegrationTest
 
   def test_getting_session_id
     with_test_route_set do
-      get '/set_session_value'
+      get "/set_session_value"
       assert_response :success
-      assert cookies['_session_id']
-      session_id = cookies['_session_id']
+      assert cookies["_session_id"]
+      session_id = cookies["_session_id"]
 
-      get '/get_session_id'
+      get "/get_session_id"
       assert_response :success
       assert_equal session_id, response.body, "should be able to read session id without accessing the session hash"
     end
@@ -118,16 +120,16 @@ class CacheStoreTest < ActionDispatch::IntegrationTest
   def test_deserializes_unloaded_class
     with_test_route_set do
       with_autoload_path "session_autoload_test" do
-        get '/set_serialized_session_value'
+        get "/set_serialized_session_value"
         assert_response :success
-        assert cookies['_session_id']
+        assert cookies["_session_id"]
       end
       with_autoload_path "session_autoload_test" do
-        get '/get_session_id'
+        get "/get_session_id"
         assert_response :success
       end
       with_autoload_path "session_autoload_test" do
-        get '/get_session_value'
+        get "/get_session_value"
         assert_response :success
         assert_equal 'foo: #<SessionAutoloadTest::Foo bar:"baz">', response.body, "should auto-load unloaded class"
       end
@@ -136,27 +138,27 @@ class CacheStoreTest < ActionDispatch::IntegrationTest
 
   def test_doesnt_write_session_cookie_if_session_id_is_already_exists
     with_test_route_set do
-      get '/set_session_value'
+      get "/set_session_value"
       assert_response :success
-      assert cookies['_session_id']
+      assert cookies["_session_id"]
 
-      get '/get_session_value'
+      get "/get_session_value"
       assert_response :success
-      assert_equal nil, headers['Set-Cookie'], "should not resend the cookie again if session_id cookie is already exists"
+      assert_nil headers["Set-Cookie"], "should not resend the cookie again if session_id cookie is already exists"
     end
   end
 
   def test_prevents_session_fixation
     with_test_route_set do
-      assert_equal nil, @cache.read('_session_id:0xhax')
+      assert_nil @cache.read("_session_id:0xhax")
 
-      cookies['_session_id'] = '0xhax'
-      get '/set_session_value'
+      cookies["_session_id"] = "0xhax"
+      get "/set_session_value"
 
       assert_response :success
-      assert_not_equal '0xhax', cookies['_session_id']
-      assert_equal nil, @cache.read('_session_id:0xhax')
-      assert_equal({'foo' => 'bar'}, @cache.read("_session_id:#{cookies['_session_id']}"))
+      assert_not_equal "0xhax", cookies["_session_id"]
+      assert_nil @cache.read("_session_id:0xhax")
+      assert_equal({ "foo" => "bar" }, @cache.read("_session_id:#{cookies['_session_id']}"))
     end
   end
 
@@ -165,13 +167,13 @@ class CacheStoreTest < ActionDispatch::IntegrationTest
       with_routing do |set|
         set.draw do
           ActiveSupport::Deprecation.silence do
-            get ':action', :to => ::CacheStoreTest::TestController
+            get ":action", to: ::CacheStoreTest::TestController
           end
         end
 
         @app = self.class.build_app(set) do |middleware|
           @cache = ActiveSupport::Cache::MemoryStore.new
-          middleware.use ActionDispatch::Session::CacheStore, :key => '_session_id', :cache => @cache
+          middleware.use ActionDispatch::Session::CacheStore, key: "_session_id", cache: @cache
           middleware.delete ActionDispatch::ShowExceptions
         end
 
diff --git a/actionpack/test/dispatch/session/cookie_store_test.rb b/actionpack/test/dispatch/session/cookie_store_test.rb
index 09cb1d925f..e34426a471 100644
--- a/actionpack/test/dispatch/session/cookie_store_test.rb
+++ b/actionpack/test/dispatch/session/cookie_store_test.rb
@@ -1,14 +1,21 @@
-require 'abstract_unit'
-require 'stringio'
-require 'active_support/key_generator'
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "stringio"
+require "active_support/key_generator"
+require "active_support/messages/rotation_configuration"
 
 class CookieStoreTest < ActionDispatch::IntegrationTest
-  SessionKey = '_myapp_session'
-  SessionSecret = 'b3c631c314c0bbca50c1b2843150fe33'
-  Generator = ActiveSupport::LegacyKeyGenerator.new(SessionSecret)
+  SessionKey = "_myapp_session"
+  SessionSecret = "b3c631c314c0bbca50c1b2843150fe33"
+  SessionSalt   = "authenticated encrypted cookie"
+
+  Generator = ActiveSupport::KeyGenerator.new(SessionSecret, iterations: 1000)
+  Rotations = ActiveSupport::Messages::RotationConfiguration.new
 
-  Verifier = ActiveSupport::MessageVerifier.new(SessionSecret, :digest => 'SHA1')
-  SignedBar = Verifier.generate(:foo => "bar", :session_id => SecureRandom.hex(16))
+  Encryptor = ActiveSupport::MessageEncryptor.new(
+    Generator.generate_key(SessionSalt, 32), cipher: "aes-256-gcm", serializer: Marshal
+  )
 
   class TestController < ActionController::Base
     def no_session_access
@@ -21,7 +28,7 @@ class CookieStoreTest < ActionDispatch::IntegrationTest
 
     def set_session_value
       session[:foo] = "bar"
-      render plain: Rack::Utils.escape(Verifier.generate(session.to_hash))
+      render body: nil
     end
 
     def get_session_value
@@ -48,7 +55,7 @@ class CookieStoreTest < ActionDispatch::IntegrationTest
     end
 
     def raise_data_overflow
-      session[:foo] = 'bye!' * 1024
+      session[:foo] = "bye!" * 1024
       head :ok
     end
 
@@ -63,19 +70,35 @@ class CookieStoreTest < ActionDispatch::IntegrationTest
     end
   end
 
+  def parse_cookie_from_header
+    cookie_matches = headers["Set-Cookie"].match(/#{SessionKey}=([^;]+)/)
+    cookie_matches && cookie_matches[1]
+  end
+
+  def assert_session_cookie(cookie_string, contents)
+    assert_includes headers["Set-Cookie"], cookie_string
+
+    session_value = parse_cookie_from_header
+    session_data = Encryptor.decrypt_and_verify(Rack::Utils.unescape(session_value)) rescue nil
+
+    assert_not_nil session_data, "session failed to decrypt"
+    assert_equal session_data.slice(*contents.keys), contents
+  end
+
   def test_setting_session_value
     with_test_route_set do
-      get '/set_session_value'
+      get "/set_session_value"
+
       assert_response :success
-      assert_equal "_myapp_session=#{response.body}; path=/; HttpOnly",
-        headers['Set-Cookie']
+      assert_session_cookie "path=/; HttpOnly", "foo" => "bar"
     end
   end
 
   def test_getting_session_value
     with_test_route_set do
-      cookies[SessionKey] = SignedBar
-      get '/get_session_value'
+      get "/set_session_value"
+      get "/get_session_value"
+
       assert_response :success
       assert_equal 'foo: "bar"', response.body
     end
@@ -83,13 +106,14 @@ class CookieStoreTest < ActionDispatch::IntegrationTest
 
   def test_getting_session_id
     with_test_route_set do
-      cookies[SessionKey] = SignedBar
-      get '/persistent_session_id'
+      get "/set_session_value"
+      get "/persistent_session_id"
+
       assert_response :success
       assert_equal 32, response.body.size
       session_id = response.body
 
-      get '/get_session_id'
+      get "/get_session_id"
       assert_response :success
       assert_equal "id: #{session_id}", response.body, "should be able to read session id without accessing the session hash"
     end
@@ -97,51 +121,55 @@ class CookieStoreTest < ActionDispatch::IntegrationTest
 
   def test_disregards_tampered_sessions
     with_test_route_set do
-      cookies[SessionKey] = "BAh7BjoIZm9vIghiYXI%3D--123456780"
-      get '/get_session_value'
+      encryptor = ActiveSupport::MessageEncryptor.new("A" * 32, cipher: "aes-256-gcm", serializer: Marshal)
+
+      cookies[SessionKey] = encryptor.encrypt_and_sign("foo" => "bar", "session_id" => "abc")
+
+      get "/get_session_value"
+
       assert_response :success
-      assert_equal 'foo: nil', response.body
+      assert_equal "foo: nil", response.body
     end
   end
 
   def test_does_not_set_secure_cookies_over_http
-    with_test_route_set(:secure => true) do
-      get '/set_session_value'
+    with_test_route_set(secure: true) do
+      get "/set_session_value"
       assert_response :success
-      assert_equal nil, headers['Set-Cookie']
+      assert_nil headers["Set-Cookie"]
     end
   end
 
   def test_properly_renew_cookies
     with_test_route_set do
-      get '/set_session_value'
-      get '/persistent_session_id'
+      get "/set_session_value"
+      get "/persistent_session_id"
       session_id = response.body
-      get '/renew_session_id'
-      get '/persistent_session_id'
+      get "/renew_session_id"
+      get "/persistent_session_id"
       assert_not_equal response.body, session_id
     end
   end
 
   def test_does_set_secure_cookies_over_https
-    with_test_route_set(:secure => true) do
-      get '/set_session_value', headers: { 'HTTPS' => 'on' }
+    with_test_route_set(secure: true) do
+      get "/set_session_value", headers: { "HTTPS" => "on" }
+
       assert_response :success
-      assert_equal "_myapp_session=#{response.body}; path=/; secure; HttpOnly",
-        headers['Set-Cookie']
+      assert_session_cookie "path=/; secure; HttpOnly", "foo" => "bar"
     end
   end
 
   # {:foo=>#<SessionAutoloadTest::Foo bar:"baz">, :session_id=>"ce8b0752a6ab7c7af3cdb8a80e6b9e46"}
-  SignedSerializedCookie = "BAh7BzoIZm9vbzodU2Vzc2lvbkF1dG9sb2FkVGVzdDo6Rm9vBjoJQGJhciIIYmF6Og9zZXNzaW9uX2lkIiVjZThiMDc1MmE2YWI3YzdhZjNjZGI4YTgwZTZiOWU0Ng==--2bf3af1ae8bd4e52b9ac2099258ace0c380e601c"
+  EncryptedSerializedCookie = "9RZ2Fij0qLveUwM4s+CCjGqhpjyUC8jiBIf/AiBr9M3TB8xh2vQZtvSOMfN3uf6oYbbpIDHAcOFIEl69FcW1ozQYeSrCLonYCazoh34ZdYskIQfGwCiSYleVXG1OD9Z4jFqeVArw4Ewm0paOOPLbN1rc6A==--I359v/KWdZ1ok0ey--JFFhuPOY7WUo6tB/eP05Aw=="
 
   def test_deserializes_unloaded_classes_on_get_id
     with_test_route_set do
       with_autoload_path "session_autoload_test" do
-        cookies[SessionKey] = SignedSerializedCookie
-        get '/get_session_id'
+        cookies[SessionKey] = EncryptedSerializedCookie
+        get "/get_session_id"
         assert_response :success
-        assert_equal 'id: ce8b0752a6ab7c7af3cdb8a80e6b9e46', response.body, "should auto-load unloaded class"
+        assert_equal "id: ce8b0752a6ab7c7af3cdb8a80e6b9e46", response.body, "should auto-load unloaded class"
       end
     end
   end
@@ -149,8 +177,8 @@ class CookieStoreTest < ActionDispatch::IntegrationTest
   def test_deserializes_unloaded_classes_on_get_value
     with_test_route_set do
       with_autoload_path "session_autoload_test" do
-        cookies[SessionKey] = SignedSerializedCookie
-        get '/get_session_value'
+        cookies[SessionKey] = EncryptedSerializedCookie
+        get "/get_session_value"
         assert_response :success
         assert_equal 'foo: #<SessionAutoloadTest::Foo bar:"baz">', response.body, "should auto-load unloaded class"
       end
@@ -160,107 +188,103 @@ class CookieStoreTest < ActionDispatch::IntegrationTest
   def test_close_raises_when_data_overflows
     with_test_route_set do
       assert_raise(ActionDispatch::Cookies::CookieOverflow) {
-        get '/raise_data_overflow'
+        get "/raise_data_overflow"
       }
     end
   end
 
   def test_doesnt_write_session_cookie_if_session_is_not_accessed
     with_test_route_set do
-      get '/no_session_access'
+      get "/no_session_access"
       assert_response :success
-      assert_equal nil, headers['Set-Cookie']
+      assert_nil headers["Set-Cookie"]
     end
   end
 
   def test_doesnt_write_session_cookie_if_session_is_unchanged
     with_test_route_set do
-      cookies[SessionKey] = "BAh7BjoIZm9vIghiYXI%3D--" +
+      cookies[SessionKey] = "BAh7BjoIZm9vIghiYXI%3D--" \
         "fef868465920f415f2c0652d6910d3af288a0367"
-      get '/no_session_access'
+      get "/no_session_access"
       assert_response :success
-      assert_equal nil, headers['Set-Cookie']
+      assert_nil headers["Set-Cookie"]
     end
   end
 
   def test_setting_session_value_after_session_reset
     with_test_route_set do
-      get '/set_session_value'
+      get "/set_session_value"
       assert_response :success
       session_payload = response.body
-      assert_equal "_myapp_session=#{response.body}; path=/; HttpOnly",
-        headers['Set-Cookie']
+      assert_session_cookie "path=/; HttpOnly", "foo" => "bar"
 
-      get '/call_reset_session'
+      get "/call_reset_session"
       assert_response :success
-      assert_not_equal [], headers['Set-Cookie']
+      assert_not_equal [], headers["Set-Cookie"]
       assert_not_nil session_payload
       assert_not_equal session_payload, cookies[SessionKey]
 
-      get '/get_session_value'
+      get "/get_session_value"
       assert_response :success
-      assert_equal 'foo: nil', response.body
+      assert_equal "foo: nil", response.body
     end
   end
 
   def test_class_type_after_session_reset
     with_test_route_set do
-      get '/set_session_value'
+      get "/set_session_value"
       assert_response :success
-      assert_equal "_myapp_session=#{response.body}; path=/; HttpOnly",
-        headers['Set-Cookie']
+      assert_session_cookie "path=/; HttpOnly", "foo" => "bar"
 
-      get '/get_class_after_reset_session'
+      get "/get_class_after_reset_session"
       assert_response :success
-      assert_not_equal [], headers['Set-Cookie']
-      assert_equal 'class: ActionDispatch::Request::Session', response.body
+      assert_not_equal [], headers["Set-Cookie"]
+      assert_equal "class: ActionDispatch::Request::Session", response.body
     end
   end
 
   def test_getting_from_nonexistent_session
     with_test_route_set do
-      get '/get_session_value'
+      get "/get_session_value"
       assert_response :success
-      assert_equal 'foo: nil', response.body
-      assert_nil headers['Set-Cookie'], "should only create session on write, not read"
+      assert_equal "foo: nil", response.body
+      assert_nil headers["Set-Cookie"], "should only create session on write, not read"
     end
   end
 
   def test_setting_session_value_after_session_clear
     with_test_route_set do
-      get '/set_session_value'
+      get "/set_session_value"
       assert_response :success
-      assert_equal "_myapp_session=#{response.body}; path=/; HttpOnly",
-        headers['Set-Cookie']
+      assert_session_cookie "path=/; HttpOnly", "foo" => "bar"
 
-      get '/call_session_clear'
+      get "/call_session_clear"
       assert_response :success
 
-      get '/get_session_value'
+      get "/get_session_value"
       assert_response :success
-      assert_equal 'foo: nil', response.body
+      assert_equal "foo: nil", response.body
     end
   end
 
   def test_persistent_session_id
     with_test_route_set do
-      cookies[SessionKey] = SignedBar
-      get '/persistent_session_id'
+      get "/set_session_value"
+      get "/persistent_session_id"
       assert_response :success
       assert_equal 32, response.body.size
       session_id = response.body
-      get '/persistent_session_id'
+      get "/persistent_session_id"
       assert_equal session_id, response.body
       reset!
-      get '/persistent_session_id'
+      get "/persistent_session_id"
       assert_not_equal session_id, response.body
     end
   end
 
   def test_setting_session_id_to_nil_is_respected
     with_test_route_set do
-      cookies[SessionKey] = SignedBar
-
+      get "/set_session_value"
       get "/get_session_id"
       sid = response.body
       assert_equal 36, sid.size
@@ -271,64 +295,86 @@ class CookieStoreTest < ActionDispatch::IntegrationTest
   end
 
   def test_session_store_with_expire_after
-    with_test_route_set(:expire_after => 5.hours) do
+    with_test_route_set(expire_after: 5.hours) do
       # First request accesses the session
       time = Time.local(2008, 4, 24)
-      cookie_body = nil
 
       Time.stub :now, time do
         expected_expiry = (time + 5.hours).gmtime.strftime("%a, %d %b %Y %H:%M:%S -0000")
 
-        cookies[SessionKey] = SignedBar
+        get "/set_session_value"
 
-        get '/set_session_value'
         assert_response :success
-
-        cookie_body = response.body
-        assert_equal "_myapp_session=#{cookie_body}; path=/; expires=#{expected_expiry}; HttpOnly",
-          headers['Set-Cookie']
+        assert_session_cookie "path=/; expires=#{expected_expiry}; HttpOnly", "foo" => "bar"
       end
 
       # Second request does not access the session
-      time = Time.local(2008, 4, 25)
+      time = time + 3.hours
       Time.stub :now, time do
         expected_expiry = (time + 5.hours).gmtime.strftime("%a, %d %b %Y %H:%M:%S -0000")
 
-        get '/no_session_access'
+        get "/no_session_access"
+
         assert_response :success
+        assert_session_cookie "path=/; expires=#{expected_expiry}; HttpOnly", "foo" => "bar"
+      end
+    end
+  end
+
+  def test_session_store_with_expire_after_does_not_accept_expired_session
+    with_test_route_set(expire_after: 5.hours) do
+      # First request accesses the session
+      time = Time.local(2017, 11, 12)
+
+      Time.stub :now, time do
+        expected_expiry = (time + 5.hours).gmtime.strftime("%a, %d %b %Y %H:%M:%S -0000")
+
+        get "/set_session_value"
+        get "/get_session_value"
 
-        assert_equal "_myapp_session=#{cookie_body}; path=/; expires=#{expected_expiry}; HttpOnly",
-          headers['Set-Cookie']
+        assert_response :success
+        assert_equal 'foo: "bar"', response.body
+        assert_session_cookie "path=/; expires=#{expected_expiry}; HttpOnly", "foo" => "bar"
+      end
+
+      # Second request is beyond the expiry time and the session is invalidated
+      time += 5.hours + 1.minute
+
+      Time.stub :now, time do
+        get "/get_session_value"
+
+        assert_response :success
+        assert_equal "foo: nil", response.body
       end
     end
   end
 
   def test_session_store_with_explicit_domain
-    with_test_route_set(:domain => "example.es") do
-      get '/set_session_value'
-      assert_match(/domain=example\.es/, headers['Set-Cookie'])
-      headers['Set-Cookie']
+    with_test_route_set(domain: "example.es") do
+      get "/set_session_value"
+      assert_match(/domain=example\.es/, headers["Set-Cookie"])
+      headers["Set-Cookie"]
     end
   end
 
   def test_session_store_without_domain
     with_test_route_set do
-      get '/set_session_value'
-      assert_no_match(/domain\=/, headers['Set-Cookie'])
+      get "/set_session_value"
+      assert_no_match(/domain\=/, headers["Set-Cookie"])
     end
   end
 
   def test_session_store_with_nil_domain
-    with_test_route_set(:domain => nil) do
-      get '/set_session_value'
-      assert_no_match(/domain\=/, headers['Set-Cookie'])
+    with_test_route_set(domain: nil) do
+      get "/set_session_value"
+      assert_no_match(/domain\=/, headers["Set-Cookie"])
     end
   end
 
   def test_session_store_with_all_domains
-    with_test_route_set(:domain => :all) do
-      get '/set_session_value'
-      assert_match(/domain=\.example\.com/, headers['Set-Cookie'])
+    with_test_route_set(domain: :all) do
+      get "/set_session_value"
+      assert_match(/domain=\.example\.com/, headers["Set-Cookie"])
     end
   end
 
@@ -338,7 +384,15 @@ class CookieStoreTest < ActionDispatch::IntegrationTest
     def get(path, *args)
       args[0] ||= {}
       args[0][:headers] ||= {}
-      args[0][:headers]["action_dispatch.key_generator"] ||= Generator
+      args[0][:headers].tap do |config|
+        config["action_dispatch.secret_key_base"] = SessionSecret
+        config["action_dispatch.authenticated_encrypted_cookie_salt"] = SessionSalt
+        config["action_dispatch.use_authenticated_cookie_encryption"] = true
+
+        config["action_dispatch.key_generator"] ||= Generator
+        config["action_dispatch.cookies_rotations"] ||= Rotations
+      end
+
       super(path, *args)
     end
 
@@ -346,11 +400,11 @@ class CookieStoreTest < ActionDispatch::IntegrationTest
       with_routing do |set|
         set.draw do
           ActiveSupport::Deprecation.silence do
-            get ':action', :to => ::CookieStoreTest::TestController
+            get ":action", to: ::CookieStoreTest::TestController
           end
         end
 
-        options = { :key => SessionKey }.merge!(options)
+        options = { key: SessionKey }.merge!(options)
 
         @app = self.class.build_app(set) do |middleware|
           middleware.use ActionDispatch::Session::CookieStore, options
@@ -360,5 +414,4 @@ class CookieStoreTest < ActionDispatch::IntegrationTest
         yield
       end
     end
-
 end
diff --git a/actionpack/test/dispatch/session/mem_cache_store_test.rb b/actionpack/test/dispatch/session/mem_cache_store_test.rb
index 18cb227dad..9b51ee1cad 100644
--- a/actionpack/test/dispatch/session/mem_cache_store_test.rb
+++ b/actionpack/test/dispatch/session/mem_cache_store_test.rb
@@ -1,5 +1,7 @@
-require 'abstract_unit'
-require 'securerandom'
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "securerandom"
 
 # You need to start a memcached server inorder to run these tests
 class MemCacheStoreTest < ActionDispatch::IntegrationTest
@@ -35,17 +37,17 @@ class MemCacheStoreTest < ActionDispatch::IntegrationTest
   end
 
   begin
-    require 'dalli'
-    ss = Dalli::Client.new('localhost:11211').stats
-    raise Dalli::DalliError unless ss['localhost:11211']
+    require "dalli"
+    ss = Dalli::Client.new("localhost:11211").stats
+    raise Dalli::DalliError unless ss["localhost:11211"]
 
     def test_setting_and_getting_session_value
       with_test_route_set do
-        get '/set_session_value'
+        get "/set_session_value"
         assert_response :success
-        assert cookies['_session_id']
+        assert cookies["_session_id"]
 
-        get '/get_session_value'
+        get "/get_session_value"
         assert_response :success
         assert_equal 'foo: "bar"', response.body
       end
@@ -55,9 +57,9 @@ class MemCacheStoreTest < ActionDispatch::IntegrationTest
 
     def test_getting_nil_session_value
       with_test_route_set do
-        get '/get_session_value'
+        get "/get_session_value"
         assert_response :success
-        assert_equal 'foo: nil', response.body
+        assert_equal "foo: nil", response.body
       end
     rescue Dalli::RingError => ex
       skip ex.message, ex.backtrace
@@ -65,20 +67,20 @@ class MemCacheStoreTest < ActionDispatch::IntegrationTest
 
     def test_getting_session_value_after_session_reset
       with_test_route_set do
-        get '/set_session_value'
+        get "/set_session_value"
         assert_response :success
-        assert cookies['_session_id']
-        session_cookie = cookies.send(:hash_for)['_session_id']
+        assert cookies["_session_id"]
+        session_cookie = cookies.send(:hash_for)["_session_id"]
 
-        get '/call_reset_session'
+        get "/call_reset_session"
         assert_response :success
-        assert_not_equal [], headers['Set-Cookie']
+        assert_not_equal [], headers["Set-Cookie"]
 
         cookies << session_cookie # replace our new session_id with our old, pre-reset session_id
 
-        get '/get_session_value'
+        get "/get_session_value"
         assert_response :success
-        assert_equal 'foo: nil', response.body, "data for this session should have been obliterated from memcached"
+        assert_equal "foo: nil", response.body, "data for this session should have been obliterated from memcached"
       end
     rescue Dalli::RingError => ex
       skip ex.message, ex.backtrace
@@ -86,10 +88,10 @@ class MemCacheStoreTest < ActionDispatch::IntegrationTest
 
     def test_getting_from_nonexistent_session
       with_test_route_set do
-        get '/get_session_value'
+        get "/get_session_value"
         assert_response :success
-        assert_equal 'foo: nil', response.body
-        assert_nil cookies['_session_id'], "should only create session on write, not read"
+        assert_equal "foo: nil", response.body
+        assert_nil cookies["_session_id"], "should only create session on write, not read"
       end
     rescue Dalli::RingError => ex
       skip ex.message, ex.backtrace
@@ -97,20 +99,20 @@ class MemCacheStoreTest < ActionDispatch::IntegrationTest
 
     def test_setting_session_value_after_session_reset
       with_test_route_set do
-        get '/set_session_value'
+        get "/set_session_value"
         assert_response :success
-        assert cookies['_session_id']
-        session_id = cookies['_session_id']
+        assert cookies["_session_id"]
+        session_id = cookies["_session_id"]
 
-        get '/call_reset_session'
+        get "/call_reset_session"
         assert_response :success
-        assert_not_equal [], headers['Set-Cookie']
+        assert_not_equal [], headers["Set-Cookie"]
 
-        get '/get_session_value'
+        get "/get_session_value"
         assert_response :success
-        assert_equal 'foo: nil', response.body
+        assert_equal "foo: nil", response.body
 
-        get '/get_session_id'
+        get "/get_session_id"
         assert_response :success
         assert_not_equal session_id, response.body
       end
@@ -120,12 +122,12 @@ class MemCacheStoreTest < ActionDispatch::IntegrationTest
 
     def test_getting_session_id
       with_test_route_set do
-        get '/set_session_value'
+        get "/set_session_value"
         assert_response :success
-        assert cookies['_session_id']
-        session_id = cookies['_session_id']
+        assert cookies["_session_id"]
+        session_id = cookies["_session_id"]
 
-        get '/get_session_id'
+        get "/get_session_id"
         assert_response :success
         assert_equal session_id, response.body, "should be able to read session id without accessing the session hash"
       end
@@ -136,12 +138,12 @@ class MemCacheStoreTest < ActionDispatch::IntegrationTest
     def test_deserializes_unloaded_class
       with_test_route_set do
         with_autoload_path "session_autoload_test" do
-          get '/set_serialized_session_value'
+          get "/set_serialized_session_value"
           assert_response :success
-          assert cookies['_session_id']
+          assert cookies["_session_id"]
         end
         with_autoload_path "session_autoload_test" do
-          get '/get_session_id'
+          get "/get_session_id"
           assert_response :success
         end
       end
@@ -151,13 +153,13 @@ class MemCacheStoreTest < ActionDispatch::IntegrationTest
 
     def test_doesnt_write_session_cookie_if_session_id_is_already_exists
       with_test_route_set do
-        get '/set_session_value'
+        get "/set_session_value"
         assert_response :success
-        assert cookies['_session_id']
+        assert cookies["_session_id"]
 
-        get '/get_session_value'
+        get "/get_session_value"
         assert_response :success
-        assert_equal nil, headers['Set-Cookie'], "should not resend the cookie again if session_id cookie is already exists"
+        assert_nil headers["Set-Cookie"], "should not resend the cookie again if session_id cookie is already exists"
       end
     rescue Dalli::RingError => ex
       skip ex.message, ex.backtrace
@@ -165,16 +167,16 @@ class MemCacheStoreTest < ActionDispatch::IntegrationTest
 
     def test_prevents_session_fixation
       with_test_route_set do
-        get '/get_session_value'
+        get "/get_session_value"
         assert_response :success
-        assert_equal 'foo: nil', response.body
-        session_id = cookies['_session_id']
+        assert_equal "foo: nil", response.body
+        session_id = cookies["_session_id"]
 
         reset!
 
-        get '/set_session_value', params: { _session_id: session_id }
+        get "/set_session_value", params: { _session_id: session_id }
         assert_response :success
-        assert_not_equal session_id, cookies['_session_id']
+        assert_not_equal session_id, cookies["_session_id"]
       end
     rescue Dalli::RingError => ex
       skip ex.message, ex.backtrace
@@ -188,12 +190,12 @@ class MemCacheStoreTest < ActionDispatch::IntegrationTest
       with_routing do |set|
         set.draw do
           ActiveSupport::Deprecation.silence do
-            get ':action', :to => ::MemCacheStoreTest::TestController
+            get ":action", to: ::MemCacheStoreTest::TestController
           end
         end
 
         @app = self.class.build_app(set) do |middleware|
-          middleware.use ActionDispatch::Session::MemCacheStore, :key => '_session_id', :namespace => "mem_cache_store_test:#{SecureRandom.hex(10)}"
+          middleware.use ActionDispatch::Session::MemCacheStore, key: "_session_id", namespace: "mem_cache_store_test:#{SecureRandom.hex(10)}"
           middleware.delete ActionDispatch::ShowExceptions
         end
 
diff --git a/actionpack/test/dispatch/session/test_session_test.rb b/actionpack/test/dispatch/session/test_session_test.rb
index 3e61d123e3..e90162a5fe 100644
--- a/actionpack/test/dispatch/session/test_session_test.rb
+++ b/actionpack/test/dispatch/session/test_session_test.rb
@@ -1,63 +1,65 @@
-require 'abstract_unit'
-require 'stringio'
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "stringio"
 
 class ActionController::TestSessionTest < ActiveSupport::TestCase
   def test_initialize_with_values
-    session = ActionController::TestSession.new(one: 'one', two: 'two')
-    assert_equal('one', session[:one])
-    assert_equal('two', session[:two])
+    session = ActionController::TestSession.new(one: "one", two: "two")
+    assert_equal("one", session[:one])
+    assert_equal("two", session[:two])
   end
 
   def test_setting_session_item_sets_item
     session = ActionController::TestSession.new
-    session[:key] = 'value'
-    assert_equal('value', session[:key])
+    session[:key] = "value"
+    assert_equal("value", session[:key])
   end
 
   def test_calling_delete_removes_item_and_returns_its_value
     session = ActionController::TestSession.new
-    session[:key] = 'value'
-    assert_equal('value', session[:key])
-    assert_equal('value', session.delete(:key))
+    session[:key] = "value"
+    assert_equal("value", session[:key])
+    assert_equal("value", session.delete(:key))
     assert_nil(session[:key])
   end
 
   def test_calling_update_with_params_passes_to_attributes
     session = ActionController::TestSession.new
-    session.update('key' => 'value')
-    assert_equal('value', session[:key])
+    session.update("key" => "value")
+    assert_equal("value", session[:key])
   end
 
   def test_clear_empties_session
-    session = ActionController::TestSession.new(one: 'one', two: 'two')
+    session = ActionController::TestSession.new(one: "one", two: "two")
     session.clear
     assert_nil(session[:one])
     assert_nil(session[:two])
   end
 
   def test_keys_and_values
-    session = ActionController::TestSession.new(one: '1', two: '2')
+    session = ActionController::TestSession.new(one: "1", two: "2")
     assert_equal %w(one two), session.keys
     assert_equal %w(1 2), session.values
   end
 
   def test_fetch_returns_default
-    session = ActionController::TestSession.new(one: '1')
-    assert_equal('2', session.fetch(:two, '2'))
+    session = ActionController::TestSession.new(one: "1")
+    assert_equal("2", session.fetch(:two, "2"))
   end
 
   def test_fetch_on_symbol_returns_value
-    session = ActionController::TestSession.new(one: '1')
-    assert_equal('1', session.fetch(:one))
+    session = ActionController::TestSession.new(one: "1")
+    assert_equal("1", session.fetch(:one))
   end
 
   def test_fetch_on_string_returns_value
-    session = ActionController::TestSession.new(one: '1')
-    assert_equal('1', session.fetch('one'))
+    session = ActionController::TestSession.new(one: "1")
+    assert_equal("1", session.fetch("one"))
   end
 
   def test_fetch_returns_block_value
-    session = ActionController::TestSession.new(one: '1')
-    assert_equal(2, session.fetch('2') { |key| key.to_i })
+    session = ActionController::TestSession.new(one: "1")
+    assert_equal(2, session.fetch("2") { |key| key.to_i })
   end
 end
diff --git a/actionpack/test/dispatch/show_exceptions_test.rb b/actionpack/test/dispatch/show_exceptions_test.rb
index 14894d4b82..b69071b44b 100644
--- a/actionpack/test/dispatch/show_exceptions_test.rb
+++ b/actionpack/test/dispatch/show_exceptions_test.rb
@@ -1,7 +1,8 @@
-require 'abstract_unit'
+# frozen_string_literal: true
 
-class ShowExceptionsTest < ActionDispatch::IntegrationTest
+require "abstract_unit"
 
+class ShowExceptionsTest < ActionDispatch::IntegrationTest
   class Boomer
     def call(env)
       req = ActionDispatch::Request.new(env)
@@ -12,17 +13,17 @@ class ShowExceptionsTest < ActionDispatch::IntegrationTest
         begin
           raise StandardError.new
         rescue
-          raise ActionDispatch::ParamsParser::ParseError
+          raise ActionDispatch::Http::Parameters::ParseError
         end
       when "/method_not_allowed"
-        raise ActionController::MethodNotAllowed, 'PUT'
+        raise ActionController::MethodNotAllowed, "PUT"
       when "/unknown_http_method"
         raise ActionController::UnknownHttpMethod
       when "/not_found_original_exception"
         begin
           raise AbstractController::ActionNotFound.new
         rescue
-          raise ActionView::Template::Error.new('template')
+          raise ActionView::Template::Error.new("template")
         end
       else
         raise "puke!"
@@ -35,30 +36,30 @@ class ShowExceptionsTest < ActionDispatch::IntegrationTest
   test "skip exceptions app if not showing exceptions" do
     @app = ProductionApp
     assert_raise RuntimeError do
-      get "/", headers: { 'action_dispatch.show_exceptions' => false }
+      get "/", headers: { "action_dispatch.show_exceptions" => false }
     end
   end
 
   test "rescue with error page" do
     @app = ProductionApp
 
-    get "/", headers: { 'action_dispatch.show_exceptions' => true }
+    get "/", headers: { "action_dispatch.show_exceptions" => true }
     assert_response 500
     assert_equal "500 error fixture\n", body
 
-    get "/bad_params", headers: { 'action_dispatch.show_exceptions' => true }
+    get "/bad_params", headers: { "action_dispatch.show_exceptions" => true }
     assert_response 400
     assert_equal "400 error fixture\n", body
 
-    get "/not_found", headers: { 'action_dispatch.show_exceptions' => true }
+    get "/not_found", headers: { "action_dispatch.show_exceptions" => true }
     assert_response 404
     assert_equal "404 error fixture\n", body
 
-    get "/method_not_allowed", headers: { 'action_dispatch.show_exceptions' => true }
+    get "/method_not_allowed", headers: { "action_dispatch.show_exceptions" => true }
     assert_response 405
     assert_equal "", body
 
-    get "/unknown_http_method", headers: { 'action_dispatch.show_exceptions' => true }
+    get "/unknown_http_method", headers: { "action_dispatch.show_exceptions" => true }
     assert_response 405
     assert_equal "", body
   end
@@ -69,11 +70,11 @@ class ShowExceptionsTest < ActionDispatch::IntegrationTest
     begin
       @app = ProductionApp
 
-      get "/", headers: { 'action_dispatch.show_exceptions' => true }
+      get "/", headers: { "action_dispatch.show_exceptions" => true }
       assert_response 500
       assert_equal "500 localized error fixture\n", body
 
-      get "/not_found", headers: { 'action_dispatch.show_exceptions' => true }
+      get "/not_found", headers: { "action_dispatch.show_exceptions" => true }
       assert_response 404
       assert_equal "404 error fixture\n", body
     ensure
@@ -84,14 +85,14 @@ class ShowExceptionsTest < ActionDispatch::IntegrationTest
   test "sets the HTTP charset parameter" do
     @app = ProductionApp
 
-    get "/", headers: { 'action_dispatch.show_exceptions' => true }
+    get "/", headers: { "action_dispatch.show_exceptions" => true }
     assert_equal "text/html; charset=utf-8", response.headers["Content-Type"]
   end
 
   test "show registered original exception for wrapped exceptions" do
     @app = ProductionApp
 
-    get "/not_found_original_exception", headers: { 'action_dispatch.show_exceptions' => true }
+    get "/not_found_original_exception", headers: { "action_dispatch.show_exceptions" => true }
     assert_response 404
     assert_match(/404 error/, body)
   end
@@ -105,7 +106,7 @@ class ShowExceptionsTest < ActionDispatch::IntegrationTest
     end
 
     @app = ActionDispatch::ShowExceptions.new(Boomer.new, exceptions_app)
-    get "/not_found_original_exception", headers: { 'action_dispatch.show_exceptions' => true }
+    get "/not_found_original_exception", headers: { "action_dispatch.show_exceptions" => true }
     assert_response 404
     assert_equal "YOU FAILED", body
   end
@@ -116,7 +117,7 @@ class ShowExceptionsTest < ActionDispatch::IntegrationTest
     end
 
     @app = ActionDispatch::ShowExceptions.new(Boomer.new, exceptions_app)
-    get "/method_not_allowed", headers: { 'action_dispatch.show_exceptions' => true }
+    get "/method_not_allowed", headers: { "action_dispatch.show_exceptions" => true }
     assert_response 405
     assert_equal "", body
   end
@@ -124,12 +125,12 @@ class ShowExceptionsTest < ActionDispatch::IntegrationTest
   test "bad params exception is returned in the correct format" do
     @app = ProductionApp
 
-    get "/bad_params", headers: { 'action_dispatch.show_exceptions' => true }
+    get "/bad_params", headers: { "action_dispatch.show_exceptions" => true }
     assert_equal "text/html; charset=utf-8", response.headers["Content-Type"]
     assert_response 400
     assert_match(/400 error/, body)
 
-    get "/bad_params.json", headers: { 'action_dispatch.show_exceptions' => true }
+    get "/bad_params.json", headers: { "action_dispatch.show_exceptions" => true }
     assert_equal "application/json; charset=utf-8", response.headers["Content-Type"]
     assert_response 400
     assert_equal("{\"status\":400,\"error\":\"Bad Request\"}", body)
diff --git a/actionpack/test/dispatch/ssl_test.rb b/actionpack/test/dispatch/ssl_test.rb
index 668b2b6cfe..8ac9502af9 100644
--- a/actionpack/test/dispatch/ssl_test.rb
+++ b/actionpack/test/dispatch/ssl_test.rb
@@ -1,7 +1,9 @@
-require 'abstract_unit'
+# frozen_string_literal: true
+
+require "abstract_unit"
 
 class SSLTest < ActionDispatch::IntegrationTest
-  HEADERS = Rack::Utils::HeaderHash.new 'Content-Type' => 'text/html'
+  HEADERS = Rack::Utils::HeaderHash.new "Content-Type" => "text/html"
 
   attr_accessor :app
 
@@ -12,26 +14,16 @@ class SSLTest < ActionDispatch::IntegrationTest
 end
 
 class RedirectSSLTest < SSLTest
-
-  def assert_not_redirected(url, headers: {}, redirect: {}, deprecated_host: nil,
-    deprecated_port: nil)
-
-    self.app = build_app ssl_options: { redirect: redirect,
-      host: deprecated_host, port: deprecated_port
-    }
-
+  def assert_not_redirected(url, headers: {}, redirect: {})
+    self.app = build_app ssl_options: { redirect: redirect }
     get url, headers: headers
     assert_response :ok
   end
 
-  def assert_redirected(redirect: {}, deprecated_host: nil, deprecated_port: nil,
-    from: 'http://a/b?c=d', to: from.sub('http', 'https'))
-
+  def assert_redirected(redirect: {}, from: "http://a/b?c=d", to: from.sub("http", "https"))
     redirect = { status: 301, body: [] }.merge(redirect)
 
-    self.app = build_app ssl_options: { redirect: redirect,
-      host: deprecated_host, port: deprecated_port
-    }
+    self.app = build_app ssl_options: { redirect: redirect }
 
     get from
     assert_response redirect[:status] || 301
@@ -39,130 +31,128 @@ class RedirectSSLTest < SSLTest
     assert_equal redirect[:body].join, @response.body
   end
 
-  test 'exclude can avoid redirect' do
-    excluding = { exclude: -> request { request.path =~ /healthcheck/ } }
+  def assert_post_redirected(redirect: {}, from: "http://a/b?c=d",
+    to: from.sub("http", "https"))
 
-    assert_not_redirected 'http://example.org/healthcheck', redirect: excluding
-    assert_redirected from: 'http://example.org/', redirect: excluding
+    self.app = build_app ssl_options: { redirect: redirect }
+
+    post from
+    assert_response redirect[:status] || 307
+    assert_redirected_to to
   end
 
-  test 'https is not redirected' do
-    assert_not_redirected 'https://example.org'
+  test "exclude can avoid redirect" do
+    excluding = { exclude: -> request { request.path =~ /healthcheck/ } }
+
+    assert_not_redirected "http://example.org/healthcheck", redirect: excluding
+    assert_redirected from: "http://example.org/", redirect: excluding
   end
 
-  test 'proxied https is not redirected' do
-    assert_not_redirected 'http://example.org', headers: { 'HTTP_X_FORWARDED_PROTO' => 'https' }
+  test "https is not redirected" do
+    assert_not_redirected "https://example.org"
   end
 
-  test 'http is redirected to https' do
-    assert_redirected
+  test "proxied https is not redirected" do
+    assert_not_redirected "http://example.org", headers: { "HTTP_X_FORWARDED_PROTO" => "https" }
   end
 
-  test 'redirect with non-301 status' do
-    assert_redirected redirect: { status: 307 }
+  test "http is redirected to https" do
+    assert_redirected
   end
 
-  test 'redirect with custom body' do
-    assert_redirected redirect: { body: ['foo'] }
+  test "http POST is redirected to https with status 307" do
+    assert_post_redirected
   end
 
-  test 'redirect to specific host' do
-    assert_redirected redirect: { host: 'ssl' }, to: 'https://ssl/b?c=d'
+  test "redirect with non-301 status" do
+    assert_redirected redirect: { status: 307 }
   end
 
-  test 'redirect to default port' do
-    assert_redirected redirect: { port: 443 }
+  test "redirect with custom body" do
+    assert_redirected redirect: { body: ["foo"] }
   end
 
-  test 'redirect to non-default port' do
-    assert_redirected redirect: { port: 8443 }, to: 'https://a:8443/b?c=d'
+  test "redirect to specific host" do
+    assert_redirected redirect: { host: "ssl" }, to: "https://ssl/b?c=d"
   end
 
-  test 'redirect to different host and non-default port' do
-    assert_redirected redirect: { host: 'ssl', port: 8443 }, to: 'https://ssl:8443/b?c=d'
+  test "redirect to default port" do
+    assert_redirected redirect: { port: 443 }
   end
 
-  test 'redirect to different host including port' do
-    assert_redirected redirect: { host: 'ssl:443' }, to: 'https://ssl:443/b?c=d'
+  test "redirect to non-default port" do
+    assert_redirected redirect: { port: 8443 }, to: "https://a:8443/b?c=d"
   end
 
-  test ':host is deprecated, moved within redirect: { host: … }' do
-    assert_deprecated do
-      assert_redirected deprecated_host: 'foo', to: 'https://foo/b?c=d'
-    end
+  test "redirect to different host and non-default port" do
+    assert_redirected redirect: { host: "ssl", port: 8443 }, to: "https://ssl:8443/b?c=d"
   end
 
-  test ':port is deprecated, moved within redirect: { port: … }' do
-    assert_deprecated do
-      assert_redirected deprecated_port: 1, to: 'https://a:1/b?c=d'
-    end
+  test "redirect to different host including port" do
+    assert_redirected redirect: { host: "ssl:443" }, to: "https://ssl:443/b?c=d"
   end
 
-  test 'no redirect with redirect set to false' do
-    assert_not_redirected 'http://example.org', redirect: false
+  test "no redirect with redirect set to false" do
+    assert_not_redirected "http://example.org", redirect: false
   end
 end
 
 class StrictTransportSecurityTest < SSLTest
-  EXPECTED = 'max-age=15552000'
-  EXPECTED_WITH_SUBDOMAINS = 'max-age=15552000; includeSubDomains'
+  EXPECTED = "max-age=15552000"
+  EXPECTED_WITH_SUBDOMAINS = "max-age=15552000; includeSubDomains"
 
-  def assert_hsts(expected, url: 'https://example.org', hsts: { subdomains: true }, headers: {})
+  def assert_hsts(expected, url: "https://example.org", hsts: { subdomains: true }, headers: {})
     self.app = build_app ssl_options: { hsts: hsts }, headers: headers
     get url
-    assert_equal expected, response.headers['Strict-Transport-Security']
+    if expected.nil?
+      assert_nil response.headers["Strict-Transport-Security"]
+    else
+      assert_equal expected, response.headers["Strict-Transport-Security"]
+    end
   end
 
-  test 'enabled by default' do
+  test "enabled by default" do
     assert_hsts EXPECTED_WITH_SUBDOMAINS
   end
 
-  test 'not sent with http:// responses' do
-    assert_hsts nil, url: 'http://example.org'
+  test "not sent with http:// responses" do
+    assert_hsts nil, url: "http://example.org"
   end
 
-  test 'defers to app-provided header' do
-    assert_hsts 'app-provided', headers: { 'Strict-Transport-Security' => 'app-provided' }
+  test "defers to app-provided header" do
+    assert_hsts "app-provided", headers: { "Strict-Transport-Security" => "app-provided" }
   end
 
-  test 'hsts: true enables default settings' do
-    assert_hsts EXPECTED, hsts: true
+  test "hsts: true enables default settings" do
+    assert_hsts EXPECTED_WITH_SUBDOMAINS, hsts: true
   end
 
-  test 'hsts: false sets max-age to zero, clearing browser HSTS settings' do
-    assert_hsts 'max-age=0', hsts: false
+  test "hsts: false sets max-age to zero, clearing browser HSTS settings" do
+    assert_hsts "max-age=0; includeSubDomains", hsts: false
   end
 
-  test ':expires sets max-age' do
-    assert_deprecated do
-      assert_hsts 'max-age=500', hsts: { expires: 500 }
-    end
+  test ":expires sets max-age" do
+    assert_hsts "max-age=500; includeSubDomains", hsts: { expires: 500 }
   end
 
-  test ':expires supports AS::Duration arguments' do
-    assert_deprecated do
-      assert_hsts 'max-age=31557600', hsts: { expires: 1.year }
-    end
+  test ":expires supports AS::Duration arguments" do
+    assert_hsts "max-age=31556952; includeSubDomains", hsts: { expires: 1.year }
   end
 
-  test 'include subdomains' do
+  test "include subdomains" do
     assert_hsts "#{EXPECTED}; includeSubDomains", hsts: { subdomains: true }
   end
 
-  test 'exclude subdomains' do
+  test "exclude subdomains" do
     assert_hsts EXPECTED, hsts: { subdomains: false }
   end
 
-  test 'opt in to browser preload lists' do
-    assert_deprecated do
-      assert_hsts "#{EXPECTED}; preload", hsts: { preload: true }
-    end
+  test "opt in to browser preload lists" do
+    assert_hsts "#{EXPECTED_WITH_SUBDOMAINS}; preload", hsts: { preload: true }
   end
 
-  test 'opt out of browser preload lists' do
-    assert_deprecated do
-      assert_hsts EXPECTED, hsts: { preload: false }
-    end
+  test "opt out of browser preload lists" do
+    assert_hsts EXPECTED_WITH_SUBDOMAINS, hsts: { preload: false }
   end
 end
 
@@ -171,60 +161,60 @@ class SecureCookiesTest < SSLTest
 
   def get(**options)
     self.app = build_app(**options)
-    super 'https://example.org'
+    super "https://example.org"
   end
 
   def assert_cookies(*expected)
-    assert_equal expected, response.headers['Set-Cookie'].split("\n")
+    assert_equal expected, response.headers["Set-Cookie"].split("\n")
   end
 
   def test_flag_cookies_as_secure
-    get headers: { 'Set-Cookie' => DEFAULT }
-    assert_cookies 'id=1; path=/; secure', 'token=abc; path=/; secure; HttpOnly'
+    get headers: { "Set-Cookie" => DEFAULT }
+    assert_cookies "id=1; path=/; secure", "token=abc; path=/; secure; HttpOnly"
   end
 
   def test_flag_cookies_as_secure_at_end_of_line
-    get headers: { 'Set-Cookie' => 'problem=def; path=/; HttpOnly; secure' }
-    assert_cookies 'problem=def; path=/; HttpOnly; secure'
+    get headers: { "Set-Cookie" => "problem=def; path=/; HttpOnly; secure" }
+    assert_cookies "problem=def; path=/; HttpOnly; secure"
   end
 
   def test_flag_cookies_as_secure_with_more_spaces_before
-    get headers: { 'Set-Cookie' => 'problem=def; path=/; HttpOnly;  secure' }
-    assert_cookies 'problem=def; path=/; HttpOnly;  secure'
+    get headers: { "Set-Cookie" => "problem=def; path=/; HttpOnly;  secure" }
+    assert_cookies "problem=def; path=/; HttpOnly;  secure"
   end
 
   def test_flag_cookies_as_secure_with_more_spaces_after
-    get headers: { 'Set-Cookie' => 'problem=def; path=/; secure;  HttpOnly' }
-    assert_cookies 'problem=def; path=/; secure;  HttpOnly'
+    get headers: { "Set-Cookie" => "problem=def; path=/; secure;  HttpOnly" }
+    assert_cookies "problem=def; path=/; secure;  HttpOnly"
   end
 
   def test_flag_cookies_as_secure_with_has_not_spaces_before
-    get headers: { 'Set-Cookie' => 'problem=def; path=/;secure; HttpOnly' }
-    assert_cookies 'problem=def; path=/;secure; HttpOnly'
+    get headers: { "Set-Cookie" => "problem=def; path=/;secure; HttpOnly" }
+    assert_cookies "problem=def; path=/;secure; HttpOnly"
   end
 
   def test_flag_cookies_as_secure_with_has_not_spaces_after
-    get headers: { 'Set-Cookie' => 'problem=def; path=/; secure;HttpOnly' }
-    assert_cookies 'problem=def; path=/; secure;HttpOnly'
+    get headers: { "Set-Cookie" => "problem=def; path=/; secure;HttpOnly" }
+    assert_cookies "problem=def; path=/; secure;HttpOnly"
   end
 
   def test_flag_cookies_as_secure_with_ignore_case
-    get headers: { 'Set-Cookie' => 'problem=def; path=/; Secure; HttpOnly' }
-    assert_cookies 'problem=def; path=/; Secure; HttpOnly'
+    get headers: { "Set-Cookie" => "problem=def; path=/; Secure; HttpOnly" }
+    assert_cookies "problem=def; path=/; Secure; HttpOnly"
   end
 
   def test_cookies_as_not_secure_with_secure_cookies_disabled
-    get headers: { 'Set-Cookie' => DEFAULT }, ssl_options: { secure_cookies: false }
+    get headers: { "Set-Cookie" => DEFAULT }, ssl_options: { secure_cookies: false }
     assert_cookies(*DEFAULT.split("\n"))
   end
 
   def test_no_cookies
     get
-    assert_nil response.headers['Set-Cookie']
+    assert_nil response.headers["Set-Cookie"]
   end
 
   def test_keeps_original_headers_behavior
-    get headers: { 'Connection' => %w[close] }
-    assert_equal 'close', response.headers['Connection']
+    get headers: { "Connection" => %w[close] }
+    assert_equal "close", response.headers["Connection"]
   end
 end
diff --git a/actionpack/test/dispatch/static_test.rb b/actionpack/test/dispatch/static_test.rb
index ea8b5e904e..0bdff68692 100644
--- a/actionpack/test/dispatch/static_test.rb
+++ b/actionpack/test/dispatch/static_test.rb
@@ -1,9 +1,11 @@
-require 'abstract_unit'
-require 'zlib'
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "zlib"
 
 module StaticTests
   DummyApp = lambda { |env|
-    [200, {"Content-Type" => "text/plain"}, ["Hello, World!"]]
+    [200, { "Content-Type" => "text/plain" }, ["Hello, World!"]]
   }
 
   def setup
@@ -29,7 +31,7 @@ module StaticTests
   end
 
   def test_handles_urls_with_ascii_8bit
-    assert_equal "Hello, World!", get("/doorkeeper%E3E4".force_encoding('ASCII-8BIT')).body
+    assert_equal "Hello, World!", get("/doorkeeper%E3E4".dup.force_encoding("ASCII-8BIT")).body
   end
 
   def test_handles_urls_with_ascii_8bit_on_win_31j
@@ -37,23 +39,13 @@ module StaticTests
       Encoding.default_internal = "Windows-31J"
       Encoding.default_external = "Windows-31J"
     end
-    assert_equal "Hello, World!", get("/doorkeeper%E3E4".force_encoding('ASCII-8BIT')).body
+    assert_equal "Hello, World!", get("/doorkeeper%E3E4".dup.force_encoding("ASCII-8BIT")).body
   end
 
   def test_handles_urls_with_null_byte
     assert_equal "Hello, World!", get("/doorkeeper%00").body
   end
 
-  def test_sets_cache_control
-    app = assert_deprecated do
-      ActionDispatch::Static.new(DummyApp, @root, "public, max-age=60")
-    end
-    response = Rack::MockRequest.new(app).request("GET", "/index.html")
-
-    assert_html "/index.html", response
-    assert_equal "public, max-age=60", response.headers["Cache-Control"]
-  end
-
   def test_serves_static_index_at_root
     assert_html "/index.html", get("/index.html")
     assert_html "/index.html", get("/index")
@@ -82,7 +74,6 @@ module StaticTests
     assert_html "means hello in Japanese\n", get("/foo/#{Rack::Utils.escape("こんにちは.html")}")
   end
 
-
   def test_serves_static_file_with_exclamation_mark_in_filename
     with_static_file "/foo/foo!bar.html" do |file|
       assert_html file, get("/foo/foo%21bar.html")
@@ -148,65 +139,74 @@ module StaticTests
 
   def test_serves_gzip_files_when_header_set
     file_name = "/gzip/application-a71b3024f80aea3181c09774ca17e712.js"
-    response  = get(file_name, 'HTTP_ACCEPT_ENCODING' => 'gzip')
+    response  = get(file_name, "HTTP_ACCEPT_ENCODING" => "gzip")
     assert_gzip  file_name, response
-    assert_equal 'application/javascript', response.headers['Content-Type']
-    assert_equal 'Accept-Encoding',        response.headers["Vary"]
-    assert_equal 'gzip',                   response.headers["Content-Encoding"]
+    assert_equal "application/javascript", response.headers["Content-Type"]
+    assert_equal "Accept-Encoding",        response.headers["Vary"]
+    assert_equal "gzip",                   response.headers["Content-Encoding"]
 
-    response  = get(file_name, 'HTTP_ACCEPT_ENCODING' => 'Gzip')
-    assert_gzip  file_name, response
+    response = get(file_name, "HTTP_ACCEPT_ENCODING" => "Gzip")
+    assert_gzip file_name, response
 
-    response  = get(file_name, 'HTTP_ACCEPT_ENCODING' => 'GZIP')
-    assert_gzip  file_name, response
+    response = get(file_name, "HTTP_ACCEPT_ENCODING" => "GZIP")
+    assert_gzip file_name, response
+
+    response = get(file_name, "HTTP_ACCEPT_ENCODING" => "compress;q=0.5, gzip;q=1.0")
+    assert_gzip file_name, response
 
-    response  = get(file_name, 'HTTP_ACCEPT_ENCODING' => '')
-    assert_not_equal 'gzip', response.headers["Content-Encoding"]
+    response = get(file_name, "HTTP_ACCEPT_ENCODING" => "")
+    assert_not_equal "gzip", response.headers["Content-Encoding"]
   end
 
   def test_does_not_modify_path_info
     file_name = "/gzip/application-a71b3024f80aea3181c09774ca17e712.js"
-    env = {'PATH_INFO' => file_name, 'HTTP_ACCEPT_ENCODING' => 'gzip', "REQUEST_METHOD" => 'POST'}
+    env = { "PATH_INFO" => file_name, "HTTP_ACCEPT_ENCODING" => "gzip", "REQUEST_METHOD" => "POST" }
     @app.call(env)
-    assert_equal file_name, env['PATH_INFO']
+    assert_equal file_name, env["PATH_INFO"]
   end
 
-  def test_serves_gzip_with_propper_content_type_fallback
+  def test_serves_gzip_with_proper_content_type_fallback
     file_name = "/gzip/foo.zoo"
-    response  = get(file_name, 'HTTP_ACCEPT_ENCODING' => 'gzip')
-    assert_gzip  file_name, response
+    response  = get(file_name, "HTTP_ACCEPT_ENCODING" => "gzip")
+    assert_gzip file_name, response
 
     default_response = get(file_name) # no gzip
-    assert_equal default_response.headers['Content-Type'], response.headers['Content-Type']
+    assert_equal default_response.headers["Content-Type"], response.headers["Content-Type"]
   end
 
   def test_serves_gzip_files_with_not_modified
     file_name = "/gzip/application-a71b3024f80aea3181c09774ca17e712.js"
     last_modified = File.mtime(File.join(@root, "#{file_name}.gz"))
-    response = get(file_name, 'HTTP_ACCEPT_ENCODING' => 'gzip', 'HTTP_IF_MODIFIED_SINCE' => last_modified.httpdate)
+    response = get(file_name, "HTTP_ACCEPT_ENCODING" => "gzip", "HTTP_IF_MODIFIED_SINCE" => last_modified.httpdate)
     assert_equal 304, response.status
-    assert_equal nil, response.headers['Content-Type']
-    assert_equal nil, response.headers['Content-Encoding']
-    assert_equal nil, response.headers['Vary']
+    assert_nil response.headers["Content-Type"]
+    assert_nil response.headers["Content-Encoding"]
+    assert_nil response.headers["Vary"]
   end
 
   def test_serves_files_with_headers
     headers = {
-      "Access-Control-Allow-Origin" => 'http://rubyonrails.org',
-      "Cache-Control"               => 'public, max-age=60',
+      "Access-Control-Allow-Origin" => "http://rubyonrails.org",
+      "Cache-Control"               => "public, max-age=60",
       "X-Custom-Header"             => "I'm a teapot"
     }
 
     app      = ActionDispatch::Static.new(DummyApp, @root, headers: headers)
     response = Rack::MockRequest.new(app).request("GET", "/foo/bar.html")
 
-    assert_equal 'http://rubyonrails.org', response.headers["Access-Control-Allow-Origin"]
-    assert_equal 'public, max-age=60',     response.headers["Cache-Control"]
+    assert_equal "http://rubyonrails.org", response.headers["Access-Control-Allow-Origin"]
+    assert_equal "public, max-age=60",     response.headers["Cache-Control"]
     assert_equal "I'm a teapot",           response.headers["X-Custom-Header"]
   end
 
+  def test_ignores_unknown_http_methods
+    app = ActionDispatch::Static.new(DummyApp, @root)
+
+    assert_nothing_raised { Rack::MockRequest.new(app).request("BAD_METHOD", "/foo/bar.html") }
+  end
+
   # Windows doesn't allow \ / : * ? " < > | in filenames
-  unless RbConfig::CONFIG['host_os'] =~ /mswin|mingw/
+  unless Gem.win_platform?
     def test_serves_static_file_with_colon
       with_static_file "/foo/foo:bar.html" do |file|
         assert_html file, get("/foo/foo%3Abar.html")
@@ -226,7 +226,7 @@ module StaticTests
 
     def assert_gzip(file_name, response)
       expected = File.read("#{FIXTURE_LOAD_PATH}/#{public_path}" + file_name)
-      actual   = Zlib::GzipReader.new(StringIO.new(response.body)).read
+      actual   = ActiveSupport::Gzip.decompress(response.body)
       assert_equal expected, actual
     end
 
@@ -258,7 +258,7 @@ class StaticTest < ActiveSupport::TestCase
   def setup
     super
     @root = "#{FIXTURE_LOAD_PATH}/public"
-    @app = ActionDispatch::Static.new(DummyApp, @root, headers: {'Cache-Control' => "public, max-age=60"})
+    @app = ActionDispatch::Static.new(DummyApp, @root, headers: { "Cache-Control" => "public, max-age=60" })
   end
 
   def public_path
@@ -268,17 +268,17 @@ class StaticTest < ActiveSupport::TestCase
   include StaticTests
 
   def test_custom_handler_called_when_file_is_outside_root
-    filename = 'shared.html.erb'
-    assert File.exist?(File.join(@root, '..', filename))
+    filename = "shared.html.erb"
+    assert File.exist?(File.join(@root, "..", filename))
     env = {
-      "REQUEST_METHOD"=>"GET",
-      "REQUEST_PATH"=>"/..%2F#{filename}",
-      "PATH_INFO"=>"/..%2F#{filename}",
-      "REQUEST_URI"=>"/..%2F#{filename}",
-      "HTTP_VERSION"=>"HTTP/1.1",
-      "SERVER_NAME"=>"localhost",
-      "SERVER_PORT"=>"8080",
-      "QUERY_STRING"=>""
+      "REQUEST_METHOD" => "GET",
+      "REQUEST_PATH" => "/..%2F#{filename}",
+      "PATH_INFO" => "/..%2F#{filename}",
+      "REQUEST_URI" => "/..%2F#{filename}",
+      "HTTP_VERSION" => "HTTP/1.1",
+      "SERVER_NAME" => "localhost",
+      "SERVER_PORT" => "8080",
+      "QUERY_STRING" => ""
     }
     assert_equal(DummyApp.call(nil), @app.call(env))
   end
@@ -294,14 +294,13 @@ class StaticTest < ActiveSupport::TestCase
     assert_html "/foo/other-index.html", get("/foo/")
     assert_html "/foo/other-index.html", get("/foo")
   end
-
 end
 
 class StaticEncodingTest < StaticTest
   def setup
     super
     @root = "#{FIXTURE_LOAD_PATH}/公共"
-    @app = ActionDispatch::Static.new(DummyApp, @root, headers: {'Cache-Control' => "public, max-age=60"})
+    @app = ActionDispatch::Static.new(DummyApp, @root, headers: { "Cache-Control" => "public, max-age=60" })
   end
 
   def public_path
diff --git a/actionpack/test/dispatch/system_testing/driver_test.rb b/actionpack/test/dispatch/system_testing/driver_test.rb
new file mode 100644
index 0000000000..fcdaf7fb4c
--- /dev/null
+++ b/actionpack/test/dispatch/system_testing/driver_test.rb
@@ -0,0 +1,53 @@
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "action_dispatch/system_testing/driver"
+
+class DriverTest < ActiveSupport::TestCase
+  test "initializing the driver" do
+    driver = ActionDispatch::SystemTesting::Driver.new(:selenium)
+    assert_equal :selenium, driver.instance_variable_get(:@name)
+  end
+
+  test "initializing the driver with a browser" do
+    driver = ActionDispatch::SystemTesting::Driver.new(:selenium, using: :chrome, screen_size: [1400, 1400], options: { url: "http://example.com/wd/hub" })
+    assert_equal :selenium, driver.instance_variable_get(:@name)
+    assert_equal :chrome, driver.instance_variable_get(:@browser)
+    assert_equal [1400, 1400], driver.instance_variable_get(:@screen_size)
+    assert_equal ({ url: "http://example.com/wd/hub" }), driver.instance_variable_get(:@options)
+  end
+
+  test "initializing the driver with a headless chrome" do
+    driver = ActionDispatch::SystemTesting::Driver.new(:selenium, using: :headless_chrome, screen_size: [1400, 1400], options: { url: "http://example.com/wd/hub" })
+    assert_equal :selenium, driver.instance_variable_get(:@name)
+    assert_equal :headless_chrome, driver.instance_variable_get(:@browser)
+    assert_equal [1400, 1400], driver.instance_variable_get(:@screen_size)
+    assert_equal ({ url: "http://example.com/wd/hub" }), driver.instance_variable_get(:@options)
+  end
+
+  test "initializing the driver with a headless firefox" do
+    driver = ActionDispatch::SystemTesting::Driver.new(:selenium, using: :headless_firefox, screen_size: [1400, 1400], options: { url: "http://example.com/wd/hub" })
+    assert_equal :selenium, driver.instance_variable_get(:@name)
+    assert_equal :headless_firefox, driver.instance_variable_get(:@browser)
+    assert_equal [1400, 1400], driver.instance_variable_get(:@screen_size)
+    assert_equal ({ url: "http://example.com/wd/hub" }), driver.instance_variable_get(:@options)
+  end
+
+  test "initializing the driver with a poltergeist" do
+    driver = ActionDispatch::SystemTesting::Driver.new(:poltergeist, screen_size: [1400, 1400], options: { js_errors: false })
+    assert_equal :poltergeist, driver.instance_variable_get(:@name)
+    assert_equal [1400, 1400], driver.instance_variable_get(:@screen_size)
+    assert_equal ({ js_errors: false }), driver.instance_variable_get(:@options)
+  end
+
+  test "initializing the driver with a webkit" do
+    driver = ActionDispatch::SystemTesting::Driver.new(:webkit, screen_size: [1400, 1400], options: { skip_image_loading: true })
+    assert_equal :webkit, driver.instance_variable_get(:@name)
+    assert_equal [1400, 1400], driver.instance_variable_get(:@screen_size)
+    assert_equal ({ skip_image_loading: true }), driver.instance_variable_get(:@options)
+  end
+
+  test "registerable? returns false if driver is rack_test" do
+    assert_not ActionDispatch::SystemTesting::Driver.new(:rack_test).send(:registerable?)
+  end
+end
diff --git a/actionpack/test/dispatch/system_testing/screenshot_helper_test.rb b/actionpack/test/dispatch/system_testing/screenshot_helper_test.rb
new file mode 100644
index 0000000000..264844fc7d
--- /dev/null
+++ b/actionpack/test/dispatch/system_testing/screenshot_helper_test.rb
@@ -0,0 +1,81 @@
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "action_dispatch/system_testing/test_helpers/screenshot_helper"
+require "capybara/dsl"
+
+class ScreenshotHelperTest < ActiveSupport::TestCase
+  test "image path is saved in tmp directory" do
+    new_test = DrivenBySeleniumWithChrome.new("x")
+
+    Rails.stub :root, Pathname.getwd do
+      assert_equal "tmp/screenshots/x.png", new_test.send(:image_path)
+    end
+  end
+
+  test "image path includes failures text if test did not pass" do
+    new_test = DrivenBySeleniumWithChrome.new("x")
+
+    Rails.stub :root, Pathname.getwd do
+      new_test.stub :passed?, false do
+        assert_equal "tmp/screenshots/failures_x.png", new_test.send(:image_path)
+      end
+    end
+  end
+
+  test "image path does not include failures text if test skipped" do
+    new_test = DrivenBySeleniumWithChrome.new("x")
+
+    Rails.stub :root, Pathname.getwd do
+      new_test.stub :passed?, false do
+        new_test.stub :skipped?, true do
+          assert_equal "tmp/screenshots/x.png", new_test.send(:image_path)
+        end
+      end
+    end
+  end
+
+  test "defaults to simple output for the screenshot" do
+    new_test = DrivenBySeleniumWithChrome.new("x")
+    assert_equal "simple", new_test.send(:output_type)
+  end
+
+  test "display_image return artifact format when specify RAILS_SYSTEM_TESTING_SCREENSHOT environment" do
+    begin
+      original_output_type = ENV["RAILS_SYSTEM_TESTING_SCREENSHOT"]
+      ENV["RAILS_SYSTEM_TESTING_SCREENSHOT"] = "artifact"
+
+      new_test = DrivenBySeleniumWithChrome.new("x")
+
+      assert_equal "artifact", new_test.send(:output_type)
+
+      Rails.stub :root, Pathname.getwd do
+        new_test.stub :passed?, false do
+          assert_match %r|url=artifact://.+?tmp/screenshots/failures_x\.png|, new_test.send(:display_image)
+        end
+      end
+    ensure
+      ENV["RAILS_SYSTEM_TESTING_SCREENSHOT"] = original_output_type
+    end
+  end
+
+  test "image path returns the relative path from current directory" do
+    new_test = DrivenBySeleniumWithChrome.new("x")
+
+    Rails.stub :root, Pathname.getwd.join("..") do
+      assert_equal "../tmp/screenshots/x.png", new_test.send(:image_path)
+    end
+  end
+end
+
+class RackTestScreenshotsTest < DrivenByRackTest
+  test "rack_test driver does not support screenshot" do
+    assert_not self.send(:supports_screenshot?)
+  end
+end
+
+class SeleniumScreenshotsTest < DrivenBySeleniumWithChrome
+  test "selenium driver supports screenshot" do
+    assert self.send(:supports_screenshot?)
+  end
+end
diff --git a/actionpack/test/dispatch/system_testing/server_test.rb b/actionpack/test/dispatch/system_testing/server_test.rb
new file mode 100644
index 0000000000..95e411faf4
--- /dev/null
+++ b/actionpack/test/dispatch/system_testing/server_test.rb
@@ -0,0 +1,32 @@
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "capybara/dsl"
+require "action_dispatch/system_testing/server"
+
+class ServerTest < ActiveSupport::TestCase
+  setup do
+    @old_capybara_server = Capybara.server
+  end
+
+  test "port is always included" do
+    ActionDispatch::SystemTesting::Server.new.run
+    assert Capybara.always_include_port, "expected Capybara.always_include_port to be true"
+  end
+
+  test "server is changed from `default` to `puma`" do
+    Capybara.server = :default
+    ActionDispatch::SystemTesting::Server.new.run
+    refute_equal Capybara.server, Capybara.servers[:default]
+  end
+
+  test "server is not changed to `puma` when is different than default" do
+    Capybara.server = :webrick
+    ActionDispatch::SystemTesting::Server.new.run
+    assert_equal Capybara.server, Capybara.servers[:webrick]
+  end
+
+  teardown do
+    Capybara.server = @old_capybara_server
+  end
+end
diff --git a/actionpack/test/dispatch/system_testing/system_test_case_test.rb b/actionpack/test/dispatch/system_testing/system_test_case_test.rb
new file mode 100644
index 0000000000..b078a5abc5
--- /dev/null
+++ b/actionpack/test/dispatch/system_testing/system_test_case_test.rb
@@ -0,0 +1,84 @@
+# frozen_string_literal: true
+
+require "abstract_unit"
+
+class SetDriverToRackTestTest < DrivenByRackTest
+  test "uses rack_test" do
+    assert_equal :rack_test, Capybara.current_driver
+  end
+end
+
+class OverrideSeleniumSubclassToRackTestTest < DrivenBySeleniumWithChrome
+  driven_by :rack_test
+
+  test "uses rack_test" do
+    assert_equal :rack_test, Capybara.current_driver
+  end
+end
+
+class SetDriverToSeleniumTest < DrivenBySeleniumWithChrome
+  test "uses selenium" do
+    assert_equal :selenium, Capybara.current_driver
+  end
+end
+
+class SetDriverToSeleniumHeadlessChromeTest < DrivenBySeleniumWithHeadlessChrome
+  test "uses selenium headless chrome" do
+    assert_equal :selenium, Capybara.current_driver
+  end
+end
+
+class SetDriverToSeleniumHeadlessFirefoxTest < DrivenBySeleniumWithHeadlessFirefox
+  test "uses selenium headless firefox" do
+    assert_equal :selenium, Capybara.current_driver
+  end
+end
+
+class SetHostTest < DrivenByRackTest
+  test "sets default host" do
+    assert_equal "http://127.0.0.1", Capybara.app_host
+  end
+
+  test "overrides host" do
+    host! "http://example.com"
+
+    assert_equal "http://example.com", Capybara.app_host
+  end
+end
+
+class UndefMethodsTest < DrivenBySeleniumWithChrome
+  test "get" do
+    exception = assert_raise NoMethodError do
+      get "http://example.com"
+    end
+    assert_equal "System tests cannot make direct requests via #get; use #visit and #click_on instead. See http://www.rubydoc.info/github/teamcapybara/capybara/master#The_DSL for more information.", exception.message
+  end
+
+  test "post" do
+    exception = assert_raise NoMethodError do
+      post "http://example.com"
+    end
+    assert_equal "System tests cannot make direct requests via #post; use #visit and #click_on instead. See http://www.rubydoc.info/github/teamcapybara/capybara/master#The_DSL for more information.", exception.message
+  end
+
+  test "put" do
+    exception = assert_raise NoMethodError do
+      put "http://example.com"
+    end
+    assert_equal "System tests cannot make direct requests via #put; use #visit and #click_on instead. See http://www.rubydoc.info/github/teamcapybara/capybara/master#The_DSL for more information.", exception.message
+  end
+
+  test "patch" do
+    exception = assert_raise NoMethodError do
+      patch "http://example.com"
+    end
+    assert_equal "System tests cannot make direct requests via #patch; use #visit and #click_on instead. See http://www.rubydoc.info/github/teamcapybara/capybara/master#The_DSL for more information.", exception.message
+  end
+
+  test "delete" do
+    exception = assert_raise NoMethodError do
+      delete "http://example.com"
+    end
+    assert_equal "System tests cannot make direct requests via #delete; use #visit and #click_on instead. See http://www.rubydoc.info/github/teamcapybara/capybara/master#The_DSL for more information.", exception.message
+  end
+end
diff --git a/actionpack/test/dispatch/test_request_test.rb b/actionpack/test/dispatch/test_request_test.rb
index 3c19cbd68a..e56537d80b 100644
--- a/actionpack/test/dispatch/test_request_test.rb
+++ b/actionpack/test/dispatch/test_request_test.rb
@@ -1,4 +1,6 @@
-require 'abstract_unit'
+# frozen_string_literal: true
+
+require "abstract_unit"
 
 class TestRequestTest < ActiveSupport::TestCase
   test "sane defaults" do
@@ -30,27 +32,27 @@ class TestRequestTest < ActiveSupport::TestCase
     req = ActionDispatch::TestRequest.create({})
 
     assert_equal({}, req.cookies)
-    assert_equal nil, req.env["HTTP_COOKIE"]
+    assert_nil req.env["HTTP_COOKIE"]
 
     req.cookie_jar["user_name"] = "david"
-    assert_cookies({"user_name" => "david"}, req.cookie_jar)
+    assert_cookies({ "user_name" => "david" }, req.cookie_jar)
 
     req.cookie_jar["login"] = "XJ-122"
-    assert_cookies({"user_name" => "david", "login" => "XJ-122"}, req.cookie_jar)
+    assert_cookies({ "user_name" => "david", "login" => "XJ-122" }, req.cookie_jar)
 
     assert_nothing_raised do
       req.cookie_jar["login"] = nil
-      assert_cookies({"user_name" => "david", "login" => nil}, req.cookie_jar)
+      assert_cookies({ "user_name" => "david", "login" => nil }, req.cookie_jar)
     end
 
     req.cookie_jar.delete(:login)
-    assert_cookies({"user_name" => "david"}, req.cookie_jar)
+    assert_cookies({ "user_name" => "david" }, req.cookie_jar)
 
     req.cookie_jar.clear
     assert_cookies({}, req.cookie_jar)
 
-    req.cookie_jar.update(:user_name => "david")
-    assert_cookies({"user_name" => "david"}, req.cookie_jar)
+    req.cookie_jar.update(user_name: "david")
+    assert_cookies({ "user_name" => "david" }, req.cookie_jar)
   end
 
   test "does not complain when there is no application config" do
@@ -60,59 +62,66 @@ class TestRequestTest < ActiveSupport::TestCase
 
   test "default remote address is 0.0.0.0" do
     req = ActionDispatch::TestRequest.create({})
-    assert_equal '0.0.0.0', req.remote_addr
+    assert_equal "0.0.0.0", req.remote_addr
   end
 
   test "allows remote address to be overridden" do
-    req = ActionDispatch::TestRequest.create('REMOTE_ADDR' => '127.0.0.1')
-    assert_equal '127.0.0.1', req.remote_addr
+    req = ActionDispatch::TestRequest.create("REMOTE_ADDR" => "127.0.0.1")
+    assert_equal "127.0.0.1", req.remote_addr
   end
 
   test "default host is test.host" do
     req = ActionDispatch::TestRequest.create({})
-    assert_equal 'test.host', req.host
+    assert_equal "test.host", req.host
   end
 
   test "allows host to be overridden" do
-    req = ActionDispatch::TestRequest.create('HTTP_HOST' => 'www.example.com')
-    assert_equal 'www.example.com', req.host
+    req = ActionDispatch::TestRequest.create("HTTP_HOST" => "www.example.com")
+    assert_equal "www.example.com", req.host
   end
 
   test "default user agent is 'Rails Testing'" do
     req = ActionDispatch::TestRequest.create({})
-    assert_equal 'Rails Testing', req.user_agent
+    assert_equal "Rails Testing", req.user_agent
   end
 
   test "allows user agent to be overridden" do
-    req = ActionDispatch::TestRequest.create('HTTP_USER_AGENT' => 'GoogleBot')
-    assert_equal 'GoogleBot', req.user_agent
+    req = ActionDispatch::TestRequest.create("HTTP_USER_AGENT" => "GoogleBot")
+    assert_equal "GoogleBot", req.user_agent
+  end
+
+  test "request_method getter and setter" do
+    req = ActionDispatch::TestRequest.create
+    req.request_method # to reproduce bug caused by memoization
+    req.request_method = "POST"
+    assert_equal "POST", req.request_method
   end
 
   test "setter methods" do
     req = ActionDispatch::TestRequest.create({})
-    get = 'GET'
+    get = "GET"
 
     [
-      'request_method=', 'host=', 'request_uri=', 'path=', 'if_modified_since=', 'if_none_match=',
-      'remote_addr=', 'user_agent=', 'accept='
+      "request_method=", "host=", "request_uri=", "path=", "if_modified_since=", "if_none_match=",
+      "remote_addr=", "user_agent=", "accept="
     ].each do |method|
       req.send(method, get)
     end
 
     req.port = 8080
-    req.accept = 'hello goodbye'
-
-    assert_equal(get, req.get_header('REQUEST_METHOD'))
-    assert_equal(get, req.get_header('HTTP_HOST'))
-    assert_equal(8080, req.get_header('SERVER_PORT'))
-    assert_equal(get, req.get_header('REQUEST_URI'))
-    assert_equal(get, req.get_header('PATH_INFO'))
-    assert_equal(get, req.get_header('HTTP_IF_MODIFIED_SINCE'))
-    assert_equal(get, req.get_header('HTTP_IF_NONE_MATCH'))
-    assert_equal(get, req.get_header('REMOTE_ADDR'))
-    assert_equal(get, req.get_header('HTTP_USER_AGENT'))
-    assert_nil(req.get_header('action_dispatch.request.accepts'))
-    assert_equal('hello goodbye', req.get_header('HTTP_ACCEPT'))
+    req.accept = "hello goodbye"
+
+    assert_equal(get, req.get_header("REQUEST_METHOD"))
+    assert_equal(get, req.get_header("HTTP_HOST"))
+    assert_equal(8080, req.get_header("SERVER_PORT"))
+    assert_equal(get, req.get_header("REQUEST_URI"))
+    assert_equal(get, req.get_header("PATH_INFO"))
+    assert_equal(get, req.get_header("HTTP_IF_MODIFIED_SINCE"))
+    assert_equal(get, req.get_header("HTTP_IF_NONE_MATCH"))
+    assert_equal(get, req.get_header("REMOTE_ADDR"))
+    assert_equal(get, req.get_header("HTTP_USER_AGENT"))
+    assert_nil(req.get_header("action_dispatch.request.accepts"))
+    assert_equal("hello goodbye", req.get_header("HTTP_ACCEPT"))
   end
 
   private
diff --git a/actionpack/test/dispatch/test_response_test.rb b/actionpack/test/dispatch/test_response_test.rb
index a4f9d56a6a..f0b8f7785d 100644
--- a/actionpack/test/dispatch/test_response_test.rb
+++ b/actionpack/test/dispatch/test_response_test.rb
@@ -1,4 +1,6 @@
-require 'abstract_unit'
+# frozen_string_literal: true
+
+require "abstract_unit"
 
 class TestResponseTest < ActiveSupport::TestCase
   def assert_response_code_range(range, predicate)
@@ -17,4 +19,19 @@ class TestResponseTest < ActiveSupport::TestCase
     assert_response_code_range 500..599, :server_error?
     assert_response_code_range 400..499, :client_error?
   end
+
+  test "response parsing" do
+    response = ActionDispatch::TestResponse.create(200, {}, "")
+    assert_equal response.body, response.parsed_body
+
+    response = ActionDispatch::TestResponse.create(200, { "Content-Type" => "application/json" }, '{ "foo": "fighters" }')
+    assert_equal({ "foo" => "fighters" }, response.parsed_body)
+  end
+
+  test "response status aliases deprecated" do
+    response = ActionDispatch::TestResponse.create
+    assert_deprecated { response.success? }
+    assert_deprecated { response.missing? }
+    assert_deprecated { response.error? }
+  end
 end
diff --git a/actionpack/test/dispatch/uploaded_file_test.rb b/actionpack/test/dispatch/uploaded_file_test.rb
index 55ebbd5143..24c7135c7e 100644
--- a/actionpack/test/dispatch/uploaded_file_test.rb
+++ b/actionpack/test/dispatch/uploaded_file_test.rb
@@ -1,4 +1,6 @@
-require 'abstract_unit'
+# frozen_string_literal: true
+
+require "abstract_unit"
 
 module ActionDispatch
   class UploadedFileTest < ActiveSupport::TestCase
@@ -9,81 +11,87 @@ module ActionDispatch
     end
 
     def test_original_filename
-      uf = Http::UploadedFile.new(:filename => 'foo', :tempfile => Object.new)
-      assert_equal 'foo', uf.original_filename
+      uf = Http::UploadedFile.new(filename: "foo", tempfile: Object.new)
+      assert_equal "foo", uf.original_filename
+    end
+
+    def test_filename_is_different_object
+      file_str = "foo"
+      uf = Http::UploadedFile.new(filename: file_str, tempfile: Object.new)
+      assert_not_equal file_str.object_id, uf.original_filename.object_id
     end
 
     def test_filename_should_be_in_utf_8
-      uf = Http::UploadedFile.new(:filename => 'foo', :tempfile => Object.new)
+      uf = Http::UploadedFile.new(filename: "foo", tempfile: Object.new)
       assert_equal "UTF-8", uf.original_filename.encoding.to_s
     end
 
     def test_filename_should_always_be_in_utf_8
-      uf = Http::UploadedFile.new(:filename => 'foo'.encode(Encoding::SHIFT_JIS),
-                                  :tempfile => Object.new)
+      uf = Http::UploadedFile.new(filename: "foo".encode(Encoding::SHIFT_JIS),
+                                  tempfile: Object.new)
       assert_equal "UTF-8", uf.original_filename.encoding.to_s
     end
 
     def test_content_type
-      uf = Http::UploadedFile.new(:type => 'foo', :tempfile => Object.new)
-      assert_equal 'foo', uf.content_type
+      uf = Http::UploadedFile.new(type: "foo", tempfile: Object.new)
+      assert_equal "foo", uf.content_type
     end
 
     def test_headers
-      uf = Http::UploadedFile.new(:head => 'foo', :tempfile => Object.new)
-      assert_equal 'foo', uf.headers
+      uf = Http::UploadedFile.new(head: "foo", tempfile: Object.new)
+      assert_equal "foo", uf.headers
     end
 
     def test_tempfile
-      uf = Http::UploadedFile.new(:tempfile => 'foo')
-      assert_equal 'foo', uf.tempfile
+      uf = Http::UploadedFile.new(tempfile: "foo")
+      assert_equal "foo", uf.tempfile
     end
 
     def test_to_io_returns_the_tempfile
       tf = Object.new
-      uf = Http::UploadedFile.new(:tempfile => tf)
+      uf = Http::UploadedFile.new(tempfile: tf)
       assert_equal tf, uf.to_io
     end
 
     def test_delegates_path_to_tempfile
-      tf = Class.new { def path; 'thunderhorse' end }
-      uf = Http::UploadedFile.new(:tempfile => tf.new)
-      assert_equal 'thunderhorse', uf.path
+      tf = Class.new { def path; "thunderhorse" end }
+      uf = Http::UploadedFile.new(tempfile: tf.new)
+      assert_equal "thunderhorse", uf.path
     end
 
     def test_delegates_open_to_tempfile
-      tf = Class.new { def open; 'thunderhorse' end }
-      uf = Http::UploadedFile.new(:tempfile => tf.new)
-      assert_equal 'thunderhorse', uf.open
+      tf = Class.new { def open; "thunderhorse" end }
+      uf = Http::UploadedFile.new(tempfile: tf.new)
+      assert_equal "thunderhorse", uf.open
     end
 
     def test_delegates_close_to_tempfile
-      tf = Class.new { def close(unlink_now=false); 'thunderhorse' end }
-      uf = Http::UploadedFile.new(:tempfile => tf.new)
-      assert_equal 'thunderhorse', uf.close
+      tf = Class.new { def close(unlink_now = false); "thunderhorse" end }
+      uf = Http::UploadedFile.new(tempfile: tf.new)
+      assert_equal "thunderhorse", uf.close
     end
 
     def test_close_accepts_parameter
-      tf = Class.new { def close(unlink_now=false); "thunderhorse: #{unlink_now}" end }
-      uf = Http::UploadedFile.new(:tempfile => tf.new)
-      assert_equal 'thunderhorse: true', uf.close(true)
+      tf = Class.new { def close(unlink_now = false); "thunderhorse: #{unlink_now}" end }
+      uf = Http::UploadedFile.new(tempfile: tf.new)
+      assert_equal "thunderhorse: true", uf.close(true)
     end
 
     def test_delegates_read_to_tempfile
-      tf = Class.new { def read(length=nil, buffer=nil); 'thunderhorse' end }
-      uf = Http::UploadedFile.new(:tempfile => tf.new)
-      assert_equal 'thunderhorse', uf.read
+      tf = Class.new { def read(length = nil, buffer = nil); "thunderhorse" end }
+      uf = Http::UploadedFile.new(tempfile: tf.new)
+      assert_equal "thunderhorse", uf.read
     end
 
     def test_delegates_read_to_tempfile_with_params
-      tf = Class.new { def read(length=nil, buffer=nil); [length, buffer] end }
-      uf = Http::UploadedFile.new(:tempfile => tf.new)
+      tf = Class.new { def read(length = nil, buffer = nil); [length, buffer] end }
+      uf = Http::UploadedFile.new(tempfile: tf.new)
       assert_equal %w{ thunder horse }, uf.read(*%w{ thunder horse })
     end
 
     def test_delegate_respects_respond_to?
       tf = Class.new { def read; yield end; private :read }
-      uf = Http::UploadedFile.new(:tempfile => tf.new)
+      uf = Http::UploadedFile.new(tempfile: tf.new)
       assert_raises(NoMethodError) do
         uf.read
       end
@@ -91,15 +99,15 @@ module ActionDispatch
 
     def test_delegate_eof_to_tempfile
       tf = Class.new { def eof?; true end; }
-      uf = Http::UploadedFile.new(:tempfile => tf.new)
+      uf = Http::UploadedFile.new(tempfile: tf.new)
       assert uf.eof?
     end
 
     def test_respond_to?
       tf = Class.new { def read; yield end }
-      uf = Http::UploadedFile.new(:tempfile => tf.new)
-      assert uf.respond_to?(:headers), 'responds to headers'
-      assert uf.respond_to?(:read), 'responds to read'
+      uf = Http::UploadedFile.new(tempfile: tf.new)
+      assert uf.respond_to?(:headers), "responds to headers"
+      assert uf.respond_to?(:read), "responds to read"
     end
   end
 end
diff --git a/actionpack/test/dispatch/url_generation_test.rb b/actionpack/test/dispatch/url_generation_test.rb
index 8c9782bb90..aef9351de1 100644
--- a/actionpack/test/dispatch/url_generation_test.rb
+++ b/actionpack/test/dispatch/url_generation_test.rb
@@ -1,4 +1,6 @@
-require 'abstract_unit'
+# frozen_string_literal: true
+
+require "abstract_unit"
 
 module TestUrlGeneration
   class WithMountPoint < ActionDispatch::IntegrationTest
@@ -13,11 +15,11 @@ module TestUrlGeneration
     end
 
     Routes.draw do
-      get "/foo", :to => "my_route_generating#index", :as => :foo
+      get "/foo", to: "my_route_generating#index", as: :foo
 
       resources :bars
 
-      mount MyRouteGeneratingController.action(:index), at: '/bar'
+      mount MyRouteGeneratingController.action(:index), at: "/bar"
     end
 
     APP = build_app Routes
@@ -35,22 +37,22 @@ module TestUrlGeneration
     end
 
     test "accepting a :script_name option" do
-      assert_equal "/bar/foo", foo_path(:script_name => "/bar")
+      assert_equal "/bar/foo", foo_path(script_name: "/bar")
     end
 
     test "the request's SCRIPT_NAME takes precedence over the route" do
-      get "/foo", headers: { 'SCRIPT_NAME' => "/new", 'action_dispatch.routes' => Routes }
+      get "/foo", headers: { "SCRIPT_NAME" => "/new", "action_dispatch.routes" => Routes }
       assert_equal "/new/foo", response.body
     end
 
     test "the request's SCRIPT_NAME wraps the mounted app's" do
-      get '/new/bar/foo', headers: { 'SCRIPT_NAME' => '/new', 'PATH_INFO' => '/bar/foo', 'action_dispatch.routes' => Routes }
+      get "/new/bar/foo", headers: { "SCRIPT_NAME" => "/new", "PATH_INFO" => "/bar/foo", "action_dispatch.routes" => Routes }
       assert_equal "/new/bar/foo", response.body
     end
 
     test "handling http protocol with https set" do
       https!
-      assert_equal "http://www.example.com/foo", foo_url(:protocol => "http")
+      assert_equal "http://www.example.com/foo", foo_url(protocol: "http")
     end
 
     test "extracting protocol from host when protocol not present" do
@@ -117,25 +119,23 @@ module TestUrlGeneration
     test "generating URLs with trailing slashes" do
       assert_equal "/bars.json", bars_path(
         trailing_slash: true,
-        format: 'json'
+        format: "json"
       )
     end
 
     test "generating URLS with querystring and trailing slashes" do
       assert_equal "/bars.json?a=b", bars_path(
         trailing_slash: true,
-        a: 'b',
-        format: 'json'
+        a: "b",
+        format: "json"
       )
     end
 
     test "generating URLS with empty querystring" do
       assert_equal "/bars.json", bars_path(
         a: {},
-        format: 'json'
+        format: "json"
       )
     end
-
   end
 end
-
diff --git a/actionpack/test/fixtures/alternate_helpers/foo_helper.rb b/actionpack/test/fixtures/alternate_helpers/foo_helper.rb
index 2528584473..3aadb6145e 100644
--- a/actionpack/test/fixtures/alternate_helpers/foo_helper.rb
+++ b/actionpack/test/fixtures/alternate_helpers/foo_helper.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module FooHelper
   redefine_method(:baz) {}
 end
diff --git a/actionpack/test/fixtures/company.rb b/actionpack/test/fixtures/company.rb
index f3ac3642fa..93afdd5472 100644
--- a/actionpack/test/fixtures/company.rb
+++ b/actionpack/test/fixtures/company.rb
@@ -1,9 +1,11 @@
+# frozen_string_literal: true
+
 class Company < ActiveRecord::Base
   has_one :mascot
   self.sequence_name = :companies_nonstd_seq
 
   validates_presence_of :name
   def validate
-    errors.add('rating', 'rating should not be 2') if rating == 2
+    errors.add("rating", "rating should not be 2") if rating == 2
   end
 end
diff --git a/actionpack/test/fixtures/functional_caching/formatted_fragment_cached.html.erb b/actionpack/test/fixtures/functional_caching/formatted_fragment_cached.html.erb
index 9b88fa1f5a..dfcd423978 100644
--- a/actionpack/test/fixtures/functional_caching/formatted_fragment_cached.html.erb
+++ b/actionpack/test/fixtures/functional_caching/formatted_fragment_cached.html.erb
@@ -1,3 +1,3 @@
 <body>
-<%= cache do %><p>ERB</p><% end %>
+<%= cache("fragment") do %><p>ERB</p><% end %>
 </body>
diff --git a/actionpack/test/fixtures/functional_caching/formatted_fragment_cached.xml.builder b/actionpack/test/fixtures/functional_caching/formatted_fragment_cached.xml.builder
index efdcc28e0f..6599579740 100644
--- a/actionpack/test/fixtures/functional_caching/formatted_fragment_cached.xml.builder
+++ b/actionpack/test/fixtures/functional_caching/formatted_fragment_cached.xml.builder
@@ -1,5 +1,5 @@
 xml.body do
-  cache do
+  cache("fragment") do
     xml.p "Builder"
   end
 end
diff --git a/actionpack/test/fixtures/functional_caching/formatted_fragment_cached_with_variant.html+phone.erb b/actionpack/test/fixtures/functional_caching/formatted_fragment_cached_with_variant.html+phone.erb
index e523b74ae3..abf7017ce6 100644
--- a/actionpack/test/fixtures/functional_caching/formatted_fragment_cached_with_variant.html+phone.erb
+++ b/actionpack/test/fixtures/functional_caching/formatted_fragment_cached_with_variant.html+phone.erb
@@ -1,3 +1,3 @@
 <body>
-<%= cache do %><p>PHONE</p><% end %>
+<%= cache("fragment") do %><p>PHONE</p><% end %>
 </body>
diff --git a/actionpack/test/fixtures/functional_caching/fragment_cached.html.erb b/actionpack/test/fixtures/functional_caching/fragment_cached.html.erb
index fa5e6bd318..1148d83ad7 100644
--- a/actionpack/test/fixtures/functional_caching/fragment_cached.html.erb
+++ b/actionpack/test/fixtures/functional_caching/fragment_cached.html.erb
@@ -1,3 +1,3 @@
 Hello
-<%= cache do %>This bit's fragment cached<% end %>
+<%= cache "fragment" do %>This bit's fragment cached<% end %>
 <%= 'Ciao' %>
diff --git a/actionpack/test/fixtures/helpers/abc_helper.rb b/actionpack/test/fixtures/helpers/abc_helper.rb
index cf2774bb5f..999b9b5c6e 100644
--- a/actionpack/test/fixtures/helpers/abc_helper.rb
+++ b/actionpack/test/fixtures/helpers/abc_helper.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module AbcHelper
   def bare_a() end
 end
diff --git a/actionpack/test/fixtures/helpers/fun/games_helper.rb b/actionpack/test/fixtures/helpers/fun/games_helper.rb
index 3b7adce086..8b325927f3 100644
--- a/actionpack/test/fixtures/helpers/fun/games_helper.rb
+++ b/actionpack/test/fixtures/helpers/fun/games_helper.rb
@@ -1,5 +1,7 @@
+# frozen_string_literal: true
+
 module Fun
   module GamesHelper
     def stratego() "Iz guuut!" end
   end
-end
\ No newline at end of file
+end
diff --git a/actionpack/test/fixtures/helpers/fun/pdf_helper.rb b/actionpack/test/fixtures/helpers/fun/pdf_helper.rb
index 0171be8500..7ce6591de3 100644
--- a/actionpack/test/fixtures/helpers/fun/pdf_helper.rb
+++ b/actionpack/test/fixtures/helpers/fun/pdf_helper.rb
@@ -1,5 +1,7 @@
+# frozen_string_literal: true
+
 module Fun
   module PdfHelper
-    def foobar() 'baz' end
+    def foobar() "baz" end
   end
 end
diff --git a/actionpack/test/fixtures/helpers/just_me_helper.rb b/actionpack/test/fixtures/helpers/just_me_helper.rb
index b140a7b9b4..bd977a22d9 100644
--- a/actionpack/test/fixtures/helpers/just_me_helper.rb
+++ b/actionpack/test/fixtures/helpers/just_me_helper.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module JustMeHelper
   def me() "mine!" end
-end
\ No newline at end of file
+end
diff --git a/actionpack/test/fixtures/helpers/me_too_helper.rb b/actionpack/test/fixtures/helpers/me_too_helper.rb
index ce56042143..c6fc053dee 100644
--- a/actionpack/test/fixtures/helpers/me_too_helper.rb
+++ b/actionpack/test/fixtures/helpers/me_too_helper.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module MeTooHelper
   def me() "me too!" end
-end
\ No newline at end of file
+end
diff --git a/actionpack/test/fixtures/helpers1_pack/pack1_helper.rb b/actionpack/test/fixtures/helpers1_pack/pack1_helper.rb
index 9faa427736..cf75b6875e 100644
--- a/actionpack/test/fixtures/helpers1_pack/pack1_helper.rb
+++ b/actionpack/test/fixtures/helpers1_pack/pack1_helper.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module Pack1Helper
   def conflicting_helper
     "pack1"
diff --git a/actionpack/test/fixtures/helpers2_pack/pack2_helper.rb b/actionpack/test/fixtures/helpers2_pack/pack2_helper.rb
index cf56697dfb..c8e51d40a2 100644
--- a/actionpack/test/fixtures/helpers2_pack/pack2_helper.rb
+++ b/actionpack/test/fixtures/helpers2_pack/pack2_helper.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module Pack2Helper
   def conflicting_helper
     "pack2"
diff --git a/actionpack/test/fixtures/helpers_typo/admin/users_helper.rb b/actionpack/test/fixtures/helpers_typo/admin/users_helper.rb
index 7d2326e04d..0455e26b93 100644
--- a/actionpack/test/fixtures/helpers_typo/admin/users_helper.rb
+++ b/actionpack/test/fixtures/helpers_typo/admin/users_helper.rb
@@ -1,5 +1,6 @@
+# frozen_string_literal: true
+
 module Admin
   module UsersHelpeR
   end
 end
-
diff --git a/actionpack/test/fixtures/layouts/builder.builder b/actionpack/test/fixtures/layouts/builder.builder
index 7c7d4b2dd1..c55488edd0 100644
--- a/actionpack/test/fixtures/layouts/builder.builder
+++ b/actionpack/test/fixtures/layouts/builder.builder
@@ -1,3 +1,3 @@
 xml.wrapper do
   xml << yield
-end
\ No newline at end of file
+end
diff --git a/actionpack/test/fixtures/load_me.rb b/actionpack/test/fixtures/load_me.rb
new file mode 100644
index 0000000000..efafe6898f
--- /dev/null
+++ b/actionpack/test/fixtures/load_me.rb
@@ -0,0 +1,4 @@
+# frozen_string_literal: true
+
+class LoadMe
+end
diff --git a/actionpack/test/fixtures/multipart/mona_lisa.jpg b/actionpack/test/fixtures/multipart/mona_lisa.jpg
deleted file mode 100644
index 5cf3bef3d0..0000000000
--- a/actionpack/test/fixtures/multipart/mona_lisa.jpg
+++ /dev/null
diff --git a/actionpack/test/fixtures/multipart/ruby_on_rails.jpg b/actionpack/test/fixtures/multipart/ruby_on_rails.jpg
new file mode 100644
index 0000000000..ed284ea0ba
--- /dev/null
+++ b/actionpack/test/fixtures/multipart/ruby_on_rails.jpg
diff --git a/actionpack/test/fixtures/namespaced/implicit_render_test/hello_world.erb b/actionpack/test/fixtures/namespaced/implicit_render_test/hello_world.erb
new file mode 100644
index 0000000000..cd0875583a
--- /dev/null
+++ b/actionpack/test/fixtures/namespaced/implicit_render_test/hello_world.erb
@@ -0,0 +1 @@
+Hello world!
diff --git a/actionpack/test/fixtures/old_content_type/render_default_for_builder.builder b/actionpack/test/fixtures/old_content_type/render_default_for_builder.builder
index 598d62e2fc..15c8a7f5cf 100644
--- a/actionpack/test/fixtures/old_content_type/render_default_for_builder.builder
+++ b/actionpack/test/fixtures/old_content_type/render_default_for_builder.builder
@@ -1 +1 @@
-xml.p "Hello world!"
\ No newline at end of file
+xml.p "Hello world!"
diff --git a/actionpack/test/fixtures/respond_to/using_defaults.xml.builder b/actionpack/test/fixtures/respond_to/using_defaults.xml.builder
index 598d62e2fc..15c8a7f5cf 100644
--- a/actionpack/test/fixtures/respond_to/using_defaults.xml.builder
+++ b/actionpack/test/fixtures/respond_to/using_defaults.xml.builder
@@ -1 +1 @@
-xml.p "Hello world!"
\ No newline at end of file
+xml.p "Hello world!"
diff --git a/actionpack/test/fixtures/respond_to/using_defaults_with_type_list.xml.builder b/actionpack/test/fixtures/respond_to/using_defaults_with_type_list.xml.builder
index 598d62e2fc..15c8a7f5cf 100644
--- a/actionpack/test/fixtures/respond_to/using_defaults_with_type_list.xml.builder
+++ b/actionpack/test/fixtures/respond_to/using_defaults_with_type_list.xml.builder
@@ -1 +1 @@
-xml.p "Hello world!"
\ No newline at end of file
+xml.p "Hello world!"
diff --git a/actionpack/test/fixtures/session_autoload_test/session_autoload_test/foo.rb b/actionpack/test/fixtures/session_autoload_test/session_autoload_test/foo.rb
index 4ee7a24561..deb81c647d 100644
--- a/actionpack/test/fixtures/session_autoload_test/session_autoload_test/foo.rb
+++ b/actionpack/test/fixtures/session_autoload_test/session_autoload_test/foo.rb
@@ -1,6 +1,8 @@
+# frozen_string_literal: true
+
 module SessionAutoloadTest
   class Foo
-    def initialize(bar='baz')
+    def initialize(bar = "baz")
       @bar = bar
     end
     def inspect
diff --git a/actionpack/test/fixtures/test/formatted_xml_erb.builder b/actionpack/test/fixtures/test/formatted_xml_erb.builder
index 14fd3549fb..f98aaa34a5 100644
--- a/actionpack/test/fixtures/test/formatted_xml_erb.builder
+++ b/actionpack/test/fixtures/test/formatted_xml_erb.builder
@@ -1 +1 @@
-xml.test 'failed'
\ No newline at end of file
+xml.test "failed"
diff --git a/actionpack/test/fixtures/test/hello_xml_world.builder b/actionpack/test/fixtures/test/hello_xml_world.builder
index e7081b89fe..d16bb6b5cb 100644
--- a/actionpack/test/fixtures/test/hello_xml_world.builder
+++ b/actionpack/test/fixtures/test/hello_xml_world.builder
@@ -8,4 +8,4 @@ xml.html do
     xml.p "monks"
     xml.p "wiseguys"
   end
-end
\ No newline at end of file
+end
diff --git a/actionpack/test/fixtures/test/with_implicit_template.erb b/actionpack/test/fixtures/test/with_implicit_template.erb
new file mode 100644
index 0000000000..474488cd13
--- /dev/null
+++ b/actionpack/test/fixtures/test/with_implicit_template.erb
@@ -0,0 +1 @@
+Hello explicitly!
diff --git a/actionpack/test/journey/gtg/builder_test.rb b/actionpack/test/journey/gtg/builder_test.rb
index c1da374007..b92460884d 100644
--- a/actionpack/test/journey/gtg/builder_test.rb
+++ b/actionpack/test/journey/gtg/builder_test.rb
@@ -1,28 +1,30 @@
-require 'abstract_unit'
+# frozen_string_literal: true
+
+require "abstract_unit"
 
 module ActionDispatch
   module Journey
     module GTG
       class TestBuilder < ActiveSupport::TestCase
         def test_following_states_multi
-          table  = tt ['a|a']
-          assert_equal 1, table.move([0], 'a').length
+          table = tt ["a|a"]
+          assert_equal 1, table.move([0], "a").length
         end
 
         def test_following_states_multi_regexp
-          table  = tt [':a|b']
-          assert_equal 1, table.move([0], 'fooo').length
-          assert_equal 2, table.move([0], 'b').length
+          table = tt [":a|b"]
+          assert_equal 1, table.move([0], "fooo").length
+          assert_equal 2, table.move([0], "b").length
         end
 
         def test_multi_path
-          table  = tt ['/:a/d', '/b/c']
+          table = tt ["/:a/d", "/b/c"]
 
           [
-            [1, '/'],
-            [2, 'b'],
-            [2, '/'],
-            [1, 'c'],
+            [1, "/"],
+            [2, "b"],
+            [2, "/"],
+            [1, "c"],
           ].inject([0]) { |state, (exp, sym)|
             new = table.move(state, sym)
             assert_equal exp, new.length
@@ -38,9 +40,9 @@ module ActionDispatch
             /articles/:id(.:format)
           }
 
-          sim     = NFA::Simulator.new table
+          sim = NFA::Simulator.new table
 
-          match = sim.match '/articles/new'
+          match = sim.match "/articles/new"
           assert_equal 2, match.memos.length
         end
 
@@ -52,27 +54,27 @@ module ActionDispatch
             /articles/new(.:format)
           }
 
-          sim     = NFA::Simulator.new table
+          sim = NFA::Simulator.new table
 
-          match = sim.match '/articles/new'
+          match = sim.match "/articles/new"
           assert_equal 2, match.memos.length
         end
 
         private
-        def ast strings
-          parser = Journey::Parser.new
-          asts   = strings.map { |string|
-            memo = Object.new
-            ast  = parser.parse string
-            ast.each { |n| n.memo = memo }
-            ast
-          }
-          Nodes::Or.new asts
-        end
+          def ast(strings)
+            parser = Journey::Parser.new
+            asts   = strings.map { |string|
+              memo = Object.new
+              ast  = parser.parse string
+              ast.each { |n| n.memo = memo }
+              ast
+            }
+            Nodes::Or.new asts
+          end
 
-        def tt strings
-          Builder.new(ast(strings)).transition_table
-        end
+          def tt(strings)
+            Builder.new(ast(strings)).transition_table
+          end
       end
     end
   end
diff --git a/actionpack/test/journey/gtg/transition_table_test.rb b/actionpack/test/journey/gtg/transition_table_test.rb
index b968780d8d..9044934f05 100644
--- a/actionpack/test/journey/gtg/transition_table_test.rb
+++ b/actionpack/test/journey/gtg/transition_table_test.rb
@@ -1,5 +1,7 @@
-require 'abstract_unit'
-require 'active_support/json/decoding'
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "active_support/json/decoding"
 
 module ActionDispatch
   module Journey
@@ -14,12 +16,12 @@ module ActionDispatch
           }
 
           json = ActiveSupport::JSON.decode table.to_json
-          assert json['regexp_states']
-          assert json['string_states']
-          assert json['accepting']
+          assert json["regexp_states"]
+          assert json["string_states"]
+          assert json["accepting"]
         end
 
-        if system("dot -V 2>/dev/null")
+        if system("dot -V", 2 => File::NULL)
           def test_to_svg
             table = tt %w{
               /articles(.:format)
@@ -34,26 +36,26 @@ module ActionDispatch
         end
 
         def test_simulate_gt
-          sim = simulator_for ['/foo', '/bar']
-          assert_match sim, '/foo'
+          sim = simulator_for ["/foo", "/bar"]
+          assert_match_route sim, "/foo"
         end
 
         def test_simulate_gt_regexp
-          sim = simulator_for [':foo']
-          assert_match sim, 'foo'
+          sim = simulator_for [":foo"]
+          assert_match_route sim, "foo"
         end
 
         def test_simulate_gt_regexp_mix
-          sim = simulator_for ['/get', '/:method/foo']
-          assert_match sim, '/get'
-          assert_match sim, '/get/foo'
+          sim = simulator_for ["/get", "/:method/foo"]
+          assert_match_route sim, "/get"
+          assert_match_route sim, "/get/foo"
         end
 
         def test_simulate_optional
-          sim = simulator_for ['/foo(/bar)']
-          assert_match sim, '/foo'
-          assert_match sim, '/foo/bar'
-          assert_no_match sim, '/foo/'
+          sim = simulator_for ["/foo(/bar)"]
+          assert_match_route sim, "/foo"
+          assert_match_route sim, "/foo/bar"
+          assert_no_match_route sim, "/foo/"
         end
 
         def test_match_data
@@ -65,11 +67,11 @@ module ActionDispatch
 
           sim = GTG::Simulator.new tt
 
-          match = sim.match '/get'
-          assert_equal [paths.first], match.memos
+          memos = sim.memos "/get"
+          assert_equal [paths.first], memos
 
-          match = sim.match '/get/foo'
-          assert_equal [paths.last], match.memos
+          memos = sim.memos "/get/foo"
+          assert_equal [paths.last], memos
         end
 
         def test_match_data_ambiguous
@@ -86,29 +88,37 @@ module ActionDispatch
           builder = GTG::Builder.new ast
           sim     = GTG::Simulator.new builder.transition_table
 
-          match = sim.match '/articles/new'
-          assert_equal [paths[1], paths[3]], match.memos
+          memos = sim.memos "/articles/new"
+          assert_equal [paths[1], paths[3]], memos
         end
 
         private
-        def asts paths
-          parser  = Journey::Parser.new
-          paths.map { |x|
-            ast = parser.parse x
-            ast.each { |n| n.memo = ast}
-            ast
-          }
-        end
+          def asts(paths)
+            parser = Journey::Parser.new
+            paths.map { |x|
+              ast = parser.parse x
+              ast.each { |n| n.memo = ast }
+              ast
+            }
+          end
 
-        def tt paths
-          x = asts paths
-          builder = GTG::Builder.new Nodes::Or.new x
-          builder.transition_table
-        end
+          def tt(paths)
+            x = asts paths
+            builder = GTG::Builder.new Nodes::Or.new x
+            builder.transition_table
+          end
 
-        def simulator_for paths
-          GTG::Simulator.new tt(paths)
-        end
+          def simulator_for(paths)
+            GTG::Simulator.new tt(paths)
+          end
+
+          def assert_match_route(simulator, path)
+            assert simulator.memos(path), "Simulator should match #{path}."
+          end
+
+          def assert_no_match_route(simulator, path)
+            assert_not simulator.memos(path) { nil }, "Simulator should not match #{path}."
+          end
       end
     end
   end
diff --git a/actionpack/test/journey/nfa/simulator_test.rb b/actionpack/test/journey/nfa/simulator_test.rb
index 673a491fe5..6b9f87b452 100644
--- a/actionpack/test/journey/nfa/simulator_test.rb
+++ b/actionpack/test/journey/nfa/simulator_test.rb
@@ -1,47 +1,49 @@
-require 'abstract_unit'
+# frozen_string_literal: true
+
+require "abstract_unit"
 
 module ActionDispatch
   module Journey
     module NFA
       class TestSimulator < ActiveSupport::TestCase
         def test_simulate_simple
-          sim = simulator_for ['/foo']
-          assert_match sim, '/foo'
+          sim = simulator_for ["/foo"]
+          assert_match sim, "/foo"
         end
 
         def test_simulate_simple_no_match
-          sim = simulator_for ['/foo']
-          assert_no_match sim, 'foo'
+          sim = simulator_for ["/foo"]
+          assert_no_match sim, "foo"
         end
 
         def test_simulate_simple_no_match_too_long
-          sim = simulator_for ['/foo']
-          assert_no_match sim, '/foo/bar'
+          sim = simulator_for ["/foo"]
+          assert_no_match sim, "/foo/bar"
         end
 
         def test_simulate_simple_no_match_wrong_string
-          sim = simulator_for ['/foo']
-          assert_no_match sim, '/bar'
+          sim = simulator_for ["/foo"]
+          assert_no_match sim, "/bar"
         end
 
         def test_simulate_regex
-          sim = simulator_for ['/:foo/bar']
-          assert_match sim, '/bar/bar'
-          assert_match sim, '/foo/bar'
+          sim = simulator_for ["/:foo/bar"]
+          assert_match sim, "/bar/bar"
+          assert_match sim, "/foo/bar"
         end
 
         def test_simulate_or
-          sim = simulator_for ['/foo', '/bar']
-          assert_match sim, '/bar'
-          assert_match sim, '/foo'
-          assert_no_match sim, '/baz'
+          sim = simulator_for ["/foo", "/bar"]
+          assert_match sim, "/bar"
+          assert_match sim, "/foo"
+          assert_no_match sim, "/baz"
         end
 
         def test_simulate_optional
-          sim = simulator_for ['/foo(/bar)']
-          assert_match sim, '/foo'
-          assert_match sim, '/foo/bar'
-          assert_no_match sim, '/foo/'
+          sim = simulator_for ["/foo(/bar)"]
+          assert_match sim, "/foo"
+          assert_match sim, "/foo/bar"
+          assert_no_match sim, "/foo/"
         end
 
         def test_matchdata_has_memos
@@ -49,7 +51,7 @@ module ActionDispatch
           parser  = Journey::Parser.new
           asts    = paths.map { |x|
             ast = parser.parse x
-            ast.each { |n| n.memo = ast}
+            ast.each { |n| n.memo = ast }
             ast
           }
 
@@ -59,17 +61,17 @@ module ActionDispatch
 
           sim = Simulator.new builder.transition_table
 
-          md = sim.match '/foo'
+          md = sim.match "/foo"
           assert_equal [expected], md.memos
         end
 
         def test_matchdata_memos_on_merge
           parser = Journey::Parser.new
           routes = [
-            '/articles(.:format)',
-            '/articles/new(.:format)',
-            '/articles/:id/edit(.:format)',
-            '/articles/:id(.:format)',
+            "/articles(.:format)",
+            "/articles/new(.:format)",
+            "/articles/:id/edit(.:format)",
+            "/articles/:id(.:format)",
           ].map { |path|
             ast = parser.parse path
             ast.each { |n| n.memo = ast }
@@ -80,13 +82,13 @@ module ActionDispatch
 
           ast = Nodes::Or.new routes
 
-          nfa   = Journey::NFA::Builder.new ast
+          nfa = Journey::NFA::Builder.new ast
           sim = Simulator.new nfa.transition_table
-          md = sim.match '/articles'
+          md = sim.match "/articles"
           assert_equal [asts.first], md.memos
         end
 
-        def simulator_for paths
+        def simulator_for(paths)
           parser  = Journey::Parser.new
           asts    = paths.map { |x| parser.parse x }
           builder = Builder.new Nodes::Or.new asts
diff --git a/actionpack/test/journey/nfa/transition_table_test.rb b/actionpack/test/journey/nfa/transition_table_test.rb
index 1248082c03..c23611e980 100644
--- a/actionpack/test/journey/nfa/transition_table_test.rb
+++ b/actionpack/test/journey/nfa/transition_table_test.rb
@@ -1,4 +1,6 @@
-require 'abstract_unit'
+# frozen_string_literal: true
+
+require "abstract_unit"
 
 module ActionDispatch
   module Journey
@@ -9,63 +11,63 @@ module ActionDispatch
         end
 
         def test_eclosure
-          table = tt '/'
+          table = tt "/"
           assert_equal [0], table.eclosure(0)
 
-          table = tt ':a|:b'
+          table = tt ":a|:b"
           assert_equal 3, table.eclosure(0).length
 
-          table = tt '(:a|:b)'
+          table = tt "(:a|:b)"
           assert_equal 5, table.eclosure(0).length
           assert_equal 5, table.eclosure([0]).length
         end
 
         def test_following_states_one
-          table = tt '/'
+          table = tt "/"
 
-          assert_equal [1], table.following_states(0, '/')
-          assert_equal [1], table.following_states([0], '/')
+          assert_equal [1], table.following_states(0, "/")
+          assert_equal [1], table.following_states([0], "/")
         end
 
         def test_following_states_group
-          table  = tt 'a|b'
+          table  = tt "a|b"
           states = table.eclosure 0
 
-          assert_equal 1, table.following_states(states, 'a').length
-          assert_equal 1, table.following_states(states, 'b').length
+          assert_equal 1, table.following_states(states, "a").length
+          assert_equal 1, table.following_states(states, "b").length
         end
 
         def test_following_states_multi
-          table  = tt 'a|a'
+          table  = tt "a|a"
           states = table.eclosure 0
 
-          assert_equal 2, table.following_states(states, 'a').length
-          assert_equal 0, table.following_states(states, 'b').length
+          assert_equal 2, table.following_states(states, "a").length
+          assert_equal 0, table.following_states(states, "b").length
         end
 
         def test_following_states_regexp
-          table  = tt 'a|:a'
+          table  = tt "a|:a"
           states = table.eclosure 0
 
-          assert_equal 1, table.following_states(states, 'a').length
+          assert_equal 1, table.following_states(states, "a").length
           assert_equal 1, table.following_states(states, /[^\.\/\?]+/).length
-          assert_equal 0, table.following_states(states, 'b').length
+          assert_equal 0, table.following_states(states, "b").length
         end
 
         def test_alphabet
-          table  = tt 'a|:a'
-          assert_equal [/[^\.\/\?]+/, 'a'], table.alphabet
+          table = tt "a|:a"
+          assert_equal [/[^\.\/\?]+/, "a"], table.alphabet
 
-          table  = tt 'a|a'
-          assert_equal ['a'], table.alphabet
+          table = tt "a|a"
+          assert_equal ["a"], table.alphabet
         end
 
         private
-        def tt string
-          ast     = @parser.parse string
-          builder = Builder.new ast
-          builder.transition_table
-        end
+          def tt(string)
+            ast     = @parser.parse string
+            builder = Builder.new ast
+            builder.transition_table
+          end
       end
     end
   end
diff --git a/actionpack/test/journey/nodes/symbol_test.rb b/actionpack/test/journey/nodes/symbol_test.rb
index adf85b860c..1e687acef2 100644
--- a/actionpack/test/journey/nodes/symbol_test.rb
+++ b/actionpack/test/journey/nodes/symbol_test.rb
@@ -1,4 +1,6 @@
-require 'abstract_unit'
+# frozen_string_literal: true
+
+require "abstract_unit"
 
 module ActionDispatch
   module Journey
diff --git a/actionpack/test/journey/path/pattern_test.rb b/actionpack/test/journey/path/pattern_test.rb
index 72858f5eda..3e7aea57f1 100644
--- a/actionpack/test/journey/path/pattern_test.rb
+++ b/actionpack/test/journey/path/pattern_test.rb
@@ -1,4 +1,6 @@
-require 'abstract_unit'
+# frozen_string_literal: true
+
+require "abstract_unit"
 
 module ActionDispatch
   module Journey
@@ -8,22 +10,22 @@ module ActionDispatch
 
         x = /.+/
         {
-          '/:controller(/:action)'       => %r{\A/(#{x})(?:/([^/.?]+))?\Z},
-          '/:controller/foo'             => %r{\A/(#{x})/foo\Z},
-          '/:controller/:action'         => %r{\A/(#{x})/([^/.?]+)\Z},
-          '/:controller'                 => %r{\A/(#{x})\Z},
-          '/:controller(/:action(/:id))' => %r{\A/(#{x})(?:/([^/.?]+)(?:/([^/.?]+))?)?\Z},
-          '/:controller/:action.xml'     => %r{\A/(#{x})/([^/.?]+)\.xml\Z},
-          '/:controller.:format'         => %r{\A/(#{x})\.([^/.?]+)\Z},
-          '/:controller(.:format)'       => %r{\A/(#{x})(?:\.([^/.?]+))?\Z},
-          '/:controller/*foo'            => %r{\A/(#{x})/(.+)\Z},
-          '/:controller/*foo/bar'        => %r{\A/(#{x})/(.+)/bar\Z},
-          '/:foo|*bar'                   => %r{\A/(?:([^/.?]+)|(.+))\Z},
+          "/:controller(/:action)"       => %r{\A/(#{x})(?:/([^/.?]+))?\Z},
+          "/:controller/foo"             => %r{\A/(#{x})/foo\Z},
+          "/:controller/:action"         => %r{\A/(#{x})/([^/.?]+)\Z},
+          "/:controller"                 => %r{\A/(#{x})\Z},
+          "/:controller(/:action(/:id))" => %r{\A/(#{x})(?:/([^/.?]+)(?:/([^/.?]+))?)?\Z},
+          "/:controller/:action.xml"     => %r{\A/(#{x})/([^/.?]+)\.xml\Z},
+          "/:controller.:format"         => %r{\A/(#{x})\.([^/.?]+)\Z},
+          "/:controller(.:format)"       => %r{\A/(#{x})(?:\.([^/.?]+))?\Z},
+          "/:controller/*foo"            => %r{\A/(#{x})/(.+)\Z},
+          "/:controller/*foo/bar"        => %r{\A/(#{x})/(.+)/bar\Z},
+          "/:foo|*bar"                   => %r{\A/(?:([^/.?]+)|(.+))\Z},
         }.each do |path, expected|
-          define_method(:"test_to_regexp_#{path}") do
+          define_method(:"test_to_regexp_#{Regexp.escape(path)}") do
             path = Pattern.build(
               path,
-              { :controller => /.+/ },
+              { controller: /.+/ },
               SEPARATORS,
               true
             )
@@ -32,22 +34,22 @@ module ActionDispatch
         end
 
         {
-          '/:controller(/:action)'       => %r{\A/(#{x})(?:/([^/.?]+))?},
-          '/:controller/foo'             => %r{\A/(#{x})/foo},
-          '/:controller/:action'         => %r{\A/(#{x})/([^/.?]+)},
-          '/:controller'                 => %r{\A/(#{x})},
-          '/:controller(/:action(/:id))' => %r{\A/(#{x})(?:/([^/.?]+)(?:/([^/.?]+))?)?},
-          '/:controller/:action.xml'     => %r{\A/(#{x})/([^/.?]+)\.xml},
-          '/:controller.:format'         => %r{\A/(#{x})\.([^/.?]+)},
-          '/:controller(.:format)'       => %r{\A/(#{x})(?:\.([^/.?]+))?},
-          '/:controller/*foo'            => %r{\A/(#{x})/(.+)},
-          '/:controller/*foo/bar'        => %r{\A/(#{x})/(.+)/bar},
-          '/:foo|*bar'                   => %r{\A/(?:([^/.?]+)|(.+))},
+          "/:controller(/:action)"       => %r{\A/(#{x})(?:/([^/.?]+))?},
+          "/:controller/foo"             => %r{\A/(#{x})/foo},
+          "/:controller/:action"         => %r{\A/(#{x})/([^/.?]+)},
+          "/:controller"                 => %r{\A/(#{x})},
+          "/:controller(/:action(/:id))" => %r{\A/(#{x})(?:/([^/.?]+)(?:/([^/.?]+))?)?},
+          "/:controller/:action.xml"     => %r{\A/(#{x})/([^/.?]+)\.xml},
+          "/:controller.:format"         => %r{\A/(#{x})\.([^/.?]+)},
+          "/:controller(.:format)"       => %r{\A/(#{x})(?:\.([^/.?]+))?},
+          "/:controller/*foo"            => %r{\A/(#{x})/(.+)},
+          "/:controller/*foo/bar"        => %r{\A/(#{x})/(.+)/bar},
+          "/:foo|*bar"                   => %r{\A/(?:([^/.?]+)|(.+))},
         }.each do |path, expected|
-          define_method(:"test_to_non_anchored_regexp_#{path}") do
+          define_method(:"test_to_non_anchored_regexp_#{Regexp.escape(path)}") do
             path = Pattern.build(
               path,
-              { :controller => /.+/ },
+              { controller: /.+/ },
               SEPARATORS,
               false
             )
@@ -56,21 +58,21 @@ module ActionDispatch
         end
 
         {
-          '/:controller(/:action)'       => %w{ controller action },
-          '/:controller/foo'             => %w{ controller },
-          '/:controller/:action'         => %w{ controller action },
-          '/:controller'                 => %w{ controller },
-          '/:controller(/:action(/:id))' => %w{ controller action id },
-          '/:controller/:action.xml'     => %w{ controller action },
-          '/:controller.:format'         => %w{ controller format },
-          '/:controller(.:format)'       => %w{ controller format },
-          '/:controller/*foo'            => %w{ controller foo },
-          '/:controller/*foo/bar'        => %w{ controller foo },
+          "/:controller(/:action)"       => %w{ controller action },
+          "/:controller/foo"             => %w{ controller },
+          "/:controller/:action"         => %w{ controller action },
+          "/:controller"                 => %w{ controller },
+          "/:controller(/:action(/:id))" => %w{ controller action id },
+          "/:controller/:action.xml"     => %w{ controller action },
+          "/:controller.:format"         => %w{ controller format },
+          "/:controller(.:format)"       => %w{ controller format },
+          "/:controller/*foo"            => %w{ controller foo },
+          "/:controller/*foo/bar"        => %w{ controller foo },
         }.each do |path, expected|
-          define_method(:"test_names_#{path}") do
+          define_method(:"test_names_#{Regexp.escape(path)}") do
             path = Pattern.build(
               path,
-              { :controller => /.+/ },
+              { controller: /.+/ },
               SEPARATORS,
               true
             )
@@ -80,8 +82,8 @@ module ActionDispatch
 
         def test_to_regexp_with_extended_group
           path = Pattern.build(
-            '/page/:name',
-            { :name => /
+            "/page/:name",
+            { name: /
               #ROFL
               (tender|love
               #MAO
@@ -89,16 +91,16 @@ module ActionDispatch
             SEPARATORS,
             true
           )
-          assert_match(path, '/page/tender')
-          assert_match(path, '/page/love')
-          assert_no_match(path, '/page/loving')
+          assert_match(path, "/page/tender")
+          assert_match(path, "/page/love")
+          assert_no_match(path, "/page/loving")
         end
 
         def test_optional_names
           [
-            ['/:foo(/:bar(/:baz))', %w{ bar baz }],
-            ['/:foo(/:bar)', %w{ bar }],
-            ['/:foo(/:bar)/:lol(/:baz)', %w{ bar baz }],
+            ["/:foo(/:bar(/:baz))", %w{ bar baz }],
+            ["/:foo(/:bar)", %w{ bar }],
+            ["/:foo(/:bar)/:lol(/:baz)", %w{ bar baz }],
           ].each do |pattern, list|
             path = Pattern.from_string pattern
             assert_equal list.sort, path.optional_names.sort
@@ -107,31 +109,31 @@ module ActionDispatch
 
         def test_to_regexp_match_non_optional
           path = Pattern.build(
-            '/:name',
-            { :name => /\d+/ },
+            "/:name",
+            { name: /\d+/ },
             SEPARATORS,
             true
           )
-          assert_match(path, '/123')
-          assert_no_match(path, '/')
+          assert_match(path, "/123")
+          assert_no_match(path, "/")
         end
 
         def test_to_regexp_with_group
           path = Pattern.build(
-            '/page/:name',
-            { :name => /(tender|love)/ },
+            "/page/:name",
+            { name: /(tender|love)/ },
             SEPARATORS,
             true
           )
-          assert_match(path, '/page/tender')
-          assert_match(path, '/page/love')
-          assert_no_match(path, '/page/loving')
+          assert_match(path, "/page/tender")
+          assert_match(path, "/page/love")
+          assert_no_match(path, "/page/loving")
         end
 
         def test_ast_sets_regular_expressions
-          requirements = { :name => /(tender|love)/, :value => /./ }
+          requirements = { name: /(tender|love)/, value: /./ }
           path = Pattern.build(
-            '/page/:name/:value',
+            "/page/:name/:value",
             requirements,
             SEPARATORS,
             true
@@ -146,26 +148,26 @@ module ActionDispatch
 
         def test_match_data_with_group
           path = Pattern.build(
-            '/page/:name',
-            { :name => /(tender|love)/ },
+            "/page/:name",
+            { name: /(tender|love)/ },
             SEPARATORS,
             true
           )
-          match = path.match '/page/tender'
-          assert_equal 'tender', match[1]
+          match = path.match "/page/tender"
+          assert_equal "tender", match[1]
           assert_equal 2, match.length
         end
 
         def test_match_data_with_multi_group
           path = Pattern.build(
-            '/page/:name/:id',
-            { :name => /t(((ender|love)))()/ },
+            "/page/:name/:id",
+            { name: /t(((ender|love)))()/ },
             SEPARATORS,
             true
           )
-          match = path.match '/page/tender/10'
-          assert_equal 'tender', match[1]
-          assert_equal '10', match[2]
+          match = path.match "/page/tender/10"
+          assert_equal "tender", match[1]
+          assert_equal "10", match[2]
           assert_equal 3, match.length
           assert_equal %w{ tender 10 }, match.captures
         end
@@ -173,8 +175,8 @@ module ActionDispatch
         def test_star_with_custom_re
           z = /\d+/
           path = Pattern.build(
-            '/page/*foo',
-            { :foo => z },
+            "/page/*foo",
+            { foo: z },
             SEPARATORS,
             true
           )
@@ -183,76 +185,76 @@ module ActionDispatch
 
         def test_insensitive_regexp_with_group
           path = Pattern.build(
-            '/page/:name/aaron',
-            { :name => /(tender|love)/i },
+            "/page/:name/aaron",
+            { name: /(tender|love)/i },
             SEPARATORS,
             true
           )
-          assert_match(path, '/page/TENDER/aaron')
-          assert_match(path, '/page/loVE/aaron')
-          assert_no_match(path, '/page/loVE/AAron')
+          assert_match(path, "/page/TENDER/aaron")
+          assert_match(path, "/page/loVE/aaron")
+          assert_no_match(path, "/page/loVE/AAron")
         end
 
         def test_to_regexp_with_strexp
-          path = Pattern.build('/:controller', { }, SEPARATORS, true)
+          path = Pattern.build("/:controller", {}, SEPARATORS, true)
           x = %r{\A/([^/.?]+)\Z}
 
           assert_equal(x.source, path.source)
         end
 
         def test_to_regexp_defaults
-          path = Pattern.from_string '/:controller(/:action(/:id))'
+          path = Pattern.from_string "/:controller(/:action(/:id))"
           expected = %r{\A/([^/.?]+)(?:/([^/.?]+)(?:/([^/.?]+))?)?\Z}
           assert_equal expected, path.to_regexp
         end
 
         def test_failed_match
-          path = Pattern.from_string '/:controller(/:action(/:id(.:format)))'
-          uri = 'content'
+          path = Pattern.from_string "/:controller(/:action(/:id(.:format)))"
+          uri = "content"
 
           assert_not path =~ uri
         end
 
         def test_match_controller
-          path = Pattern.from_string '/:controller(/:action(/:id(.:format)))'
-          uri = '/content'
+          path = Pattern.from_string "/:controller(/:action(/:id(.:format)))"
+          uri = "/content"
 
           match = path =~ uri
           assert_equal %w{ controller action id format }, match.names
-          assert_equal 'content', match[1]
+          assert_equal "content", match[1]
           assert_nil match[2]
           assert_nil match[3]
           assert_nil match[4]
         end
 
         def test_match_controller_action
-          path = Pattern.from_string '/:controller(/:action(/:id(.:format)))'
-          uri = '/content/list'
+          path = Pattern.from_string "/:controller(/:action(/:id(.:format)))"
+          uri = "/content/list"
 
           match = path =~ uri
           assert_equal %w{ controller action id format }, match.names
-          assert_equal 'content', match[1]
-          assert_equal 'list', match[2]
+          assert_equal "content", match[1]
+          assert_equal "list", match[2]
           assert_nil match[3]
           assert_nil match[4]
         end
 
         def test_match_controller_action_id
-          path = Pattern.from_string '/:controller(/:action(/:id(.:format)))'
-          uri = '/content/list/10'
+          path = Pattern.from_string "/:controller(/:action(/:id(.:format)))"
+          uri = "/content/list/10"
 
           match = path =~ uri
           assert_equal %w{ controller action id format }, match.names
-          assert_equal 'content', match[1]
-          assert_equal 'list', match[2]
-          assert_equal '10', match[3]
+          assert_equal "content", match[1]
+          assert_equal "list", match[2]
+          assert_equal "10", match[3]
           assert_nil match[4]
         end
 
         def test_match_literal
           path = Path::Pattern.from_string "/books(/:action(.:format))"
 
-          uri = '/books'
+          uri = "/books"
           match = path =~ uri
           assert_equal %w{ action format }, match.names
           assert_nil match[1]
@@ -262,21 +264,21 @@ module ActionDispatch
         def test_match_literal_with_action
           path = Path::Pattern.from_string "/books(/:action(.:format))"
 
-          uri = '/books/list'
+          uri = "/books/list"
           match = path =~ uri
           assert_equal %w{ action format }, match.names
-          assert_equal 'list', match[1]
+          assert_equal "list", match[1]
           assert_nil match[2]
         end
 
         def test_match_literal_with_action_and_format
           path = Path::Pattern.from_string "/books(/:action(.:format))"
 
-          uri = '/books/list.rss'
+          uri = "/books/list.rss"
           match = path =~ uri
           assert_equal %w{ action format }, match.names
-          assert_equal 'list', match[1]
-          assert_equal 'rss', match[2]
+          assert_equal "list", match[1]
+          assert_equal "rss", match[2]
         end
       end
     end
diff --git a/actionpack/test/journey/route/definition/parser_test.rb b/actionpack/test/journey/route/definition/parser_test.rb
index d7d7172a40..39693198b8 100644
--- a/actionpack/test/journey/route/definition/parser_test.rb
+++ b/actionpack/test/journey/route/definition/parser_test.rb
@@ -1,4 +1,6 @@
-require 'abstract_unit'
+# frozen_string_literal: true
+
+require "abstract_unit"
 
 module ActionDispatch
   module Journey
@@ -9,88 +11,88 @@ module ActionDispatch
         end
 
         def test_slash
-          assert_equal :SLASH, @parser.parse('/').type
-          assert_round_trip '/'
+          assert_equal :SLASH, @parser.parse("/").type
+          assert_round_trip "/"
         end
 
         def test_segment
-          assert_round_trip '/foo'
+          assert_round_trip "/foo"
         end
 
         def test_segments
-          assert_round_trip '/foo/bar'
+          assert_round_trip "/foo/bar"
         end
 
         def test_segment_symbol
-          assert_round_trip '/foo/:id'
+          assert_round_trip "/foo/:id"
         end
 
         def test_symbol
-          assert_round_trip '/:foo'
+          assert_round_trip "/:foo"
         end
 
         def test_group
-          assert_round_trip '(/:foo)'
+          assert_round_trip "(/:foo)"
         end
 
         def test_groups
-          assert_round_trip '(/:foo)(/:bar)'
+          assert_round_trip "(/:foo)(/:bar)"
         end
 
         def test_nested_groups
-          assert_round_trip '(/:foo(/:bar))'
+          assert_round_trip "(/:foo(/:bar))"
         end
 
         def test_dot_symbol
-          assert_round_trip('.:format')
+          assert_round_trip(".:format")
         end
 
         def test_dot_literal
-          assert_round_trip('.xml')
+          assert_round_trip(".xml")
         end
 
         def test_segment_dot
-          assert_round_trip('/foo.:bar')
+          assert_round_trip("/foo.:bar")
         end
 
         def test_segment_group_dot
-          assert_round_trip('/foo(.:bar)')
+          assert_round_trip("/foo(.:bar)")
         end
 
         def test_segment_group
-          assert_round_trip('/foo(/:action)')
+          assert_round_trip("/foo(/:action)")
         end
 
         def test_segment_groups
-          assert_round_trip('/foo(/:action)(/:bar)')
+          assert_round_trip("/foo(/:action)(/:bar)")
         end
 
         def test_segment_nested_groups
-          assert_round_trip('/foo(/:action(/:bar))')
+          assert_round_trip("/foo(/:action(/:bar))")
         end
 
         def test_group_followed_by_path
-          assert_round_trip('/foo(/:action)/:bar')
+          assert_round_trip("/foo(/:action)/:bar")
         end
 
         def test_star
-          assert_round_trip('*foo')
-          assert_round_trip('/*foo')
-          assert_round_trip('/bar/*foo')
-          assert_round_trip('/bar/(*foo)')
+          assert_round_trip("*foo")
+          assert_round_trip("/*foo")
+          assert_round_trip("/bar/*foo")
+          assert_round_trip("/bar/(*foo)")
         end
 
         def test_or
-          assert_round_trip('a|b')
-          assert_round_trip('a|b|c')
-          assert_round_trip('(a|b)|c')
-          assert_round_trip('a|(b|c)')
-          assert_round_trip('*a|(b|c)')
-          assert_round_trip('*a|:b|c')
+          assert_round_trip("a|b")
+          assert_round_trip("a|b|c")
+          assert_round_trip("(a|b)|c")
+          assert_round_trip("a|(b|c)")
+          assert_round_trip("*a|(b|c)")
+          assert_round_trip("*a|:b|c")
         end
 
         def test_arbitrary
-          assert_round_trip('/bar/*foo#')
+          assert_round_trip("/bar/*foo#")
         end
 
         def test_literal_dot_paren
@@ -101,7 +103,7 @@ module ActionDispatch
           assert_round_trip "/(:locale)(.:format)"
         end
 
-        def assert_round_trip str
+        def assert_round_trip(str)
           assert_equal str, @parser.parse(str).to_s
         end
       end
diff --git a/actionpack/test/journey/route/definition/scanner_test.rb b/actionpack/test/journey/route/definition/scanner_test.rb
index 7a510f1e07..070886c7df 100644
--- a/actionpack/test/journey/route/definition/scanner_test.rb
+++ b/actionpack/test/journey/route/definition/scanner_test.rb
@@ -1,4 +1,6 @@
-require 'abstract_unit'
+# frozen_string_literal: true
+
+require "abstract_unit"
 
 module ActionDispatch
   module Journey
@@ -11,44 +13,44 @@ module ActionDispatch
         # /page/:id(/:action)(.:format)
         def test_tokens
           [
-            ['/',       [[:SLASH, '/']]],
-            ['*omg',    [[:STAR, '*omg']]],
-            ['/page',   [[:SLASH, '/'], [:LITERAL, 'page']]],
-            ['/page!',  [[:SLASH, '/'], [:LITERAL, 'page!']]],
-            ['/page$',  [[:SLASH, '/'], [:LITERAL, 'page$']]],
-            ['/page&',  [[:SLASH, '/'], [:LITERAL, 'page&']]],
-            ["/page'",  [[:SLASH, '/'], [:LITERAL, "page'"]]],
-            ['/page*',  [[:SLASH, '/'], [:LITERAL, 'page*']]],
-            ['/page+',  [[:SLASH, '/'], [:LITERAL, 'page+']]],
-            ['/page,',  [[:SLASH, '/'], [:LITERAL, 'page,']]],
-            ['/page;',  [[:SLASH, '/'], [:LITERAL, 'page;']]],
-            ['/page=',  [[:SLASH, '/'], [:LITERAL, 'page=']]],
-            ['/page@',  [[:SLASH, '/'], [:LITERAL, 'page@']]],
-            ['/page\:', [[:SLASH, '/'], [:LITERAL, 'page:']]],
-            ['/page\(', [[:SLASH, '/'], [:LITERAL, 'page(']]],
-            ['/page\)', [[:SLASH, '/'], [:LITERAL, 'page)']]],
-            ['/~page',  [[:SLASH, '/'], [:LITERAL, '~page']]],
-            ['/pa-ge',  [[:SLASH, '/'], [:LITERAL, 'pa-ge']]],
-            ['/:page',  [[:SLASH, '/'], [:SYMBOL, ':page']]],
-            ['/(:page)', [
-                          [:SLASH, '/'],
-                          [:LPAREN, '('],
-                          [:SYMBOL, ':page'],
-                          [:RPAREN, ')'],
+            ["/",       [[:SLASH, "/"]]],
+            ["*omg",    [[:STAR, "*omg"]]],
+            ["/page",   [[:SLASH, "/"], [:LITERAL, "page"]]],
+            ["/page!",  [[:SLASH, "/"], [:LITERAL, "page!"]]],
+            ["/page$",  [[:SLASH, "/"], [:LITERAL, "page$"]]],
+            ["/page&",  [[:SLASH, "/"], [:LITERAL, "page&"]]],
+            ["/page'",  [[:SLASH, "/"], [:LITERAL, "page'"]]],
+            ["/page*",  [[:SLASH, "/"], [:LITERAL, "page*"]]],
+            ["/page+",  [[:SLASH, "/"], [:LITERAL, "page+"]]],
+            ["/page,",  [[:SLASH, "/"], [:LITERAL, "page,"]]],
+            ["/page;",  [[:SLASH, "/"], [:LITERAL, "page;"]]],
+            ["/page=",  [[:SLASH, "/"], [:LITERAL, "page="]]],
+            ["/page@",  [[:SLASH, "/"], [:LITERAL, "page@"]]],
+            ['/page\:', [[:SLASH, "/"], [:LITERAL, "page:"]]],
+            ['/page\(', [[:SLASH, "/"], [:LITERAL, "page("]]],
+            ['/page\)', [[:SLASH, "/"], [:LITERAL, "page)"]]],
+            ["/~page",  [[:SLASH, "/"], [:LITERAL, "~page"]]],
+            ["/pa-ge",  [[:SLASH, "/"], [:LITERAL, "pa-ge"]]],
+            ["/:page",  [[:SLASH, "/"], [:SYMBOL, ":page"]]],
+            ["/(:page)", [
+                          [:SLASH, "/"],
+                          [:LPAREN, "("],
+                          [:SYMBOL, ":page"],
+                          [:RPAREN, ")"],
                         ]],
-            ['(/:action)', [
-                            [:LPAREN, '('],
-                            [:SLASH, '/'],
-                            [:SYMBOL, ':action'],
-                            [:RPAREN, ')'],
+            ["(/:action)", [
+                            [:LPAREN, "("],
+                            [:SLASH, "/"],
+                            [:SYMBOL, ":action"],
+                            [:RPAREN, ")"],
                            ]],
-            ['(())', [[:LPAREN, '('],
-                     [:LPAREN, '('], [:RPAREN, ')'], [:RPAREN, ')']]],
-            ['(.:format)', [
-                            [:LPAREN, '('],
-                            [:DOT, '.'],
-                            [:SYMBOL, ':format'],
-                            [:RPAREN, ')'],
+            ["(())", [[:LPAREN, "("],
+                     [:LPAREN, "("], [:RPAREN, ")"], [:RPAREN, ")"]]],
+            ["(.:format)", [
+                            [:LPAREN, "("],
+                            [:DOT, "."],
+                            [:SYMBOL, ":format"],
+                            [:RPAREN, ")"],
                           ]],
           ].each do |str, expected|
             @scanner.scan_setup str
@@ -56,7 +58,7 @@ module ActionDispatch
           end
         end
 
-        def assert_tokens tokens, scanner
+        def assert_tokens(tokens, scanner)
           toks = []
           while tok = scanner.next_token
             toks << tok
diff --git a/actionpack/test/journey/route_test.rb b/actionpack/test/journey/route_test.rb
index 22c3b8113d..a8bf4a11e2 100644
--- a/actionpack/test/journey/route_test.rb
+++ b/actionpack/test/journey/route_test.rb
@@ -1,11 +1,13 @@
-require 'abstract_unit'
+# frozen_string_literal: true
+
+require "abstract_unit"
 
 module ActionDispatch
   module Journey
     class TestRoute < ActiveSupport::TestCase
       def test_initialize
         app      = Object.new
-        path     = Path::Pattern.from_string '/:controller(/:action(/:id(.:format)))'
+        path     = Path::Pattern.from_string "/:controller(/:action(/:id(.:format)))"
         defaults = {}
         route    = Route.build("name", app, path, {}, [], defaults)
 
@@ -16,7 +18,7 @@ module ActionDispatch
 
       def test_route_adds_itself_as_memo
         app      = Object.new
-        path     = Path::Pattern.from_string '/:controller(/:action(/:id(.:format)))'
+        path     = Path::Pattern.from_string "/:controller(/:action(/:id(.:format)))"
         defaults = {}
         route    = Route.build("name", app, path, {}, [], defaults)
 
@@ -26,71 +28,69 @@ module ActionDispatch
       end
 
       def test_path_requirements_override_defaults
-        path    = Path::Pattern.build(':name', { name: /love/ }, '/', true)
-        defaults  = { name: 'tender' }
-        route     = Route.build('name', nil, path, {}, [], defaults)
+        path = Path::Pattern.build(":name", { name: /love/ }, "/", true)
+        defaults  = { name: "tender" }
+        route     = Route.build("name", nil, path, {}, [], defaults)
         assert_equal(/love/, route.requirements[:name])
       end
 
       def test_ip_address
-        path  = Path::Pattern.from_string '/messages/:id(.:format)'
-        route = Route.build("name", nil, path, {:ip => '192.168.1.1'}, [],
-                          { :controller => 'foo', :action => 'bar' })
-        assert_equal '192.168.1.1', route.ip
+        path  = Path::Pattern.from_string "/messages/:id(.:format)"
+        route = Route.build("name", nil, path, { ip: "192.168.1.1" }, [],
+                          controller: "foo", action: "bar")
+        assert_equal "192.168.1.1", route.ip
       end
 
       def test_default_ip
-        path  = Path::Pattern.from_string '/messages/:id(.:format)'
+        path  = Path::Pattern.from_string "/messages/:id(.:format)"
         route = Route.build("name", nil, path, {}, [],
-                          { :controller => 'foo', :action => 'bar' })
+                          controller: "foo", action: "bar")
         assert_equal(//, route.ip)
       end
 
       def test_format_with_star
-        path  = Path::Pattern.from_string '/:controller/*extra'
+        path  = Path::Pattern.from_string "/:controller/*extra"
         route = Route.build("name", nil, path, {}, [],
-                          { :controller => 'foo', :action => 'bar' })
-        assert_equal '/foo/himom', route.format({
-          :controller => 'foo',
-          :extra      => 'himom',
-        })
+                          controller: "foo", action: "bar")
+        assert_equal "/foo/himom", route.format(
+          controller: "foo",
+          extra: "himom")
       end
 
       def test_connects_all_match
-        path  = Path::Pattern.from_string '/:controller(/:action(/:id(.:format)))'
-        route = Route.build("name", nil, path, {:action => 'bar'}, [], { :controller => 'foo' })
-
-        assert_equal '/foo/bar/10', route.format({
-          :controller => 'foo',
-          :action     => 'bar',
-          :id         => 10
-        })
+        path  = Path::Pattern.from_string "/:controller(/:action(/:id(.:format)))"
+        route = Route.build("name", nil, path, { action: "bar" }, [], controller: "foo")
+
+        assert_equal "/foo/bar/10", route.format(
+          controller: "foo",
+          action: "bar",
+          id: 10)
       end
 
       def test_extras_are_not_included_if_optional
-        path  = Path::Pattern.from_string '/page/:id(/:action)'
-        route = Route.build("name", nil, path, { }, [], { :action => 'show' })
+        path  = Path::Pattern.from_string "/page/:id(/:action)"
+        route = Route.build("name", nil, path, {}, [], action: "show")
 
-        assert_equal '/page/10', route.format({ :id => 10 })
+        assert_equal "/page/10", route.format(id: 10)
       end
 
       def test_extras_are_not_included_if_optional_with_parameter
-        path  = Path::Pattern.from_string '(/sections/:section)/pages/:id'
-        route = Route.build("name", nil, path, { }, [], { :action => 'show' })
+        path  = Path::Pattern.from_string "(/sections/:section)/pages/:id"
+        route = Route.build("name", nil, path, {}, [], action: "show")
 
-        assert_equal '/pages/10', route.format({:id => 10})
+        assert_equal "/pages/10", route.format(id: 10)
       end
 
       def test_extras_are_not_included_if_optional_parameter_is_nil
-        path  = Path::Pattern.from_string '(/sections/:section)/pages/:id'
-        route = Route.build("name", nil, path, { }, [], { :action => 'show' })
+        path  = Path::Pattern.from_string "(/sections/:section)/pages/:id"
+        route = Route.build("name", nil, path, {}, [], action: "show")
 
-        assert_equal '/pages/10', route.format({:id => 10, :section => nil})
+        assert_equal "/pages/10", route.format(id: 10, section: nil)
       end
 
       def test_score
         constraints = {}
-        defaults = {:controller=>"pages", :action=>"show"}
+        defaults = { controller: "pages", action: "show" }
 
         path = Path::Pattern.from_string "/page/:id(/:action)(.:format)"
         specific = Route.build "name", nil, path, constraints, [:controller, :action], defaults
@@ -98,7 +98,7 @@ module ActionDispatch
         path = Path::Pattern.from_string "/:controller(/:action(/:id))(.:format)"
         generic = Route.build "name", nil, path, constraints, [], {}
 
-        knowledge = {:id=>20, :controller=>"pages", :action=>"show"}
+        knowledge = { "id" => true, "controller" => true, "action" => true }
 
         routes = [specific, generic]
 
diff --git a/actionpack/test/journey/router/utils_test.rb b/actionpack/test/journey/router/utils_test.rb
index 2b505f081e..2d09098f11 100644
--- a/actionpack/test/journey/router/utils_test.rb
+++ b/actionpack/test/journey/router/utils_test.rb
@@ -1,4 +1,6 @@
-require 'abstract_unit'
+# frozen_string_literal: true
+
+require "abstract_unit"
 
 module ActionDispatch
   module Journey
@@ -21,7 +23,7 @@ module ActionDispatch
         end
 
         def test_uri_unescape_with_utf8_string
-          assert_equal "Šašinková", Utils.unescape_uri("%C5%A0a%C5%A1inkov%C3%A1".force_encoding(Encoding::US_ASCII))
+          assert_equal "Šašinková", Utils.unescape_uri("%C5%A0a%C5%A1inkov%C3%A1".dup.force_encoding(Encoding::US_ASCII))
         end
 
         def test_normalize_path_not_greedy
@@ -31,6 +33,15 @@ module ActionDispatch
         def test_normalize_path_uppercase
           assert_equal "/foo%AAbar%AAbaz", Utils.normalize_path("/foo%aabar%aabaz")
         end
+
+        def test_normalize_path_maintains_string_encoding
+          path = "/foo%AAbar%AAbaz".b
+          assert_equal Encoding::ASCII_8BIT, Utils.normalize_path(path).encoding
+        end
+
+        def test_normalize_path_with_nil
+          assert_equal "/", Utils.normalize_path(nil)
+        end
       end
     end
   end
diff --git a/actionpack/test/journey/router_test.rb b/actionpack/test/journey/router_test.rb
index 75caf56d32..183f421bcf 100644
--- a/actionpack/test/journey/router_test.rb
+++ b/actionpack/test/journey/router_test.rb
@@ -1,4 +1,6 @@
-require 'abstract_unit'
+# frozen_string_literal: true
+
+require "abstract_unit"
 
 module ActionDispatch
   module Journey
@@ -6,8 +8,8 @@ module ActionDispatch
       attr_reader :mapper, :routes, :route_set, :router
 
       def setup
-        @app       = Routing::RouteSet::Dispatcher.new({})
-        @route_set  = ActionDispatch::Routing::RouteSet.new
+        @app = Routing::RouteSet::Dispatcher.new({})
+        @route_set = ActionDispatch::Routing::RouteSet.new
         @routes = @route_set.router.routes
         @router = @route_set.router
         @formatter = @route_set.formatter
@@ -15,9 +17,9 @@ module ActionDispatch
       end
 
       def test_dashes
-        get '/foo-bar-baz', to: 'foo#bar'
+        get "/foo-bar-baz", to: "foo#bar"
 
-        env = rails_env 'PATH_INFO' => '/foo-bar-baz'
+        env = rails_env "PATH_INFO" => "/foo-bar-baz"
         called = false
         router.recognize(env) do |r, params|
           called = true
@@ -26,10 +28,10 @@ module ActionDispatch
       end
 
       def test_unicode
-        get '/ほげ', to: 'foo#bar'
+        get "/ほげ", to: "foo#bar"
 
-        #match the escaped version of /ほげ
-        env = rails_env 'PATH_INFO' => '/%E3%81%BB%E3%81%92'
+        # match the escaped version of /ほげ
+        env = rails_env "PATH_INFO" => "/%E3%81%BB%E3%81%92"
         called = false
         router.recognize(env) do |r, params|
           called = true
@@ -38,10 +40,10 @@ module ActionDispatch
       end
 
       def test_regexp_first_precedence
-        get "/whois/:domain", :domain => /\w+\.[\w\.]+/, to: "foo#bar"
+        get "/whois/:domain", domain: /\w+\.[\w\.]+/, to: "foo#bar"
         get "/whois/:id(.:format)", to: "foo#baz"
 
-        env = rails_env 'PATH_INFO' => '/whois/example.com'
+        env = rails_env "PATH_INFO" => "/whois/example.com"
 
         list = []
         router.recognize(env) do |r, params|
@@ -51,47 +53,47 @@ module ActionDispatch
 
         r = list.first
 
-        assert_equal '/whois/:domain(.:format)', r.path.spec.to_s
+        assert_equal "/whois/:domain(.:format)", r.path.spec.to_s
       end
 
       def test_required_parts_verified_are_anchored
-        get "/foo/:id", :id => /\d/, anchor: false, to: "foo#bar"
+        get "/foo/:id", id: /\d/, anchor: false, to: "foo#bar"
 
         assert_raises(ActionController::UrlGenerationError) do
-          @formatter.generate(nil, { :controller => "foo", :action => "bar", :id => '10' }, { })
+          @formatter.generate(nil, { controller: "foo", action: "bar", id: "10" }, {})
         end
       end
 
       def test_required_parts_are_verified_when_building
-        get "/foo/:id", :id => /\d+/, anchor: false, to: "foo#bar"
+        get "/foo/:id", id: /\d+/, anchor: false, to: "foo#bar"
 
-        path, _ = @formatter.generate(nil, { :controller => "foo", :action => "bar", :id => '10' }, { })
-        assert_equal '/foo/10', path
+        path, _ = @formatter.generate(nil, { controller: "foo", action: "bar", id: "10" }, {})
+        assert_equal "/foo/10", path
 
         assert_raises(ActionController::UrlGenerationError) do
-          @formatter.generate(nil, { :id => 'aa' }, { })
+          @formatter.generate(nil, { id: "aa" }, {})
         end
       end
 
       def test_only_required_parts_are_verified
-        get "/foo(/:id)", :id => /\d/, :to => "foo#bar"
+        get "/foo(/:id)", id: /\d/, to: "foo#bar"
 
-        path, _ = @formatter.generate(nil, { :controller => "foo", :action => "bar", :id => '10' }, { })
-        assert_equal '/foo/10', path
+        path, _ = @formatter.generate(nil, { controller: "foo", action: "bar", id: "10" }, {})
+        assert_equal "/foo/10", path
 
-        path, _ = @formatter.generate(nil, { :controller => "foo", :action => "bar" }, { })
-        assert_equal '/foo', path
+        path, _ = @formatter.generate(nil, { controller: "foo", action: "bar" }, {})
+        assert_equal "/foo", path
 
-        path, _ = @formatter.generate(nil, { :controller => "foo", :action => "bar", :id => 'aa' }, { })
-        assert_equal '/foo/aa', path
+        path, _ = @formatter.generate(nil, { controller: "foo", action: "bar", id: "aa" }, {})
+        assert_equal "/foo/aa", path
       end
 
       def test_knows_what_parts_are_missing_from_named_route
         route_name = "gorby_thunderhorse"
-        get "/foo/:id", :as => route_name, :id => /\d+/, :to => "foo#bar"
+        get "/foo/:id", as: route_name, id: /\d+/, to: "foo#bar"
 
         error = assert_raises(ActionController::UrlGenerationError) do
-          @formatter.generate(route_name, { }, { })
+          @formatter.generate(route_name, {}, {})
         end
 
         assert_match(/missing required keys: \[:id\]/, error.message)
@@ -101,7 +103,7 @@ module ActionDispatch
         route_name = "gorby_thunderhorse"
 
         error = assert_raises(ActionController::UrlGenerationError) do
-          @formatter.generate(route_name, { }, { })
+          @formatter.generate(route_name, {}, {})
         end
 
         assert_no_match(/missing required keys: \[\]/, error.message)
@@ -109,58 +111,58 @@ module ActionDispatch
 
       def test_X_Cascade
         get "/messages(.:format)", to: "foo#bar"
-        resp = router.serve(rails_env({ 'REQUEST_METHOD' => 'GET', 'PATH_INFO' => '/lol' }))
-        assert_equal ['Not Found'], resp.last
-        assert_equal 'pass', resp[1]['X-Cascade']
+        resp = router.serve(rails_env("REQUEST_METHOD" => "GET", "PATH_INFO" => "/lol"))
+        assert_equal ["Not Found"], resp.last
+        assert_equal "pass", resp[1]["X-Cascade"]
         assert_equal 404, resp.first
       end
 
       def test_clear_trailing_slash_from_script_name_on_root_unanchored_routes
-        app    = lambda { |env| [200, {}, ['success!']] }
-        get '/weblog', :to => app
+        app = lambda { |env| [200, {}, ["success!"]] }
+        get "/weblog", to: app
 
-        env  = rack_env('SCRIPT_NAME' => '', 'PATH_INFO' => '/weblog')
+        env  = rack_env("SCRIPT_NAME" => "", "PATH_INFO" => "/weblog")
         resp = route_set.call env
-        assert_equal ['success!'], resp.last
-        assert_equal '', env['SCRIPT_NAME']
+        assert_equal ["success!"], resp.last
+        assert_equal "", env["SCRIPT_NAME"]
       end
 
       def test_defaults_merge_correctly
-        get '/foo(/:id)', to: "foo#bar", id: nil
+        get "/foo(/:id)", to: "foo#bar", id: nil
 
-        env = rails_env 'PATH_INFO' => '/foo/10'
+        env = rails_env "PATH_INFO" => "/foo/10"
         router.recognize(env) do |r, params|
-          assert_equal({:id => '10', :controller => "foo", :action => "bar"}, params)
+          assert_equal({ id: "10", controller: "foo", action: "bar" }, params)
         end
 
-        env = rails_env 'PATH_INFO' => '/foo'
+        env = rails_env "PATH_INFO" => "/foo"
         router.recognize(env) do |r, params|
-          assert_equal({:id => nil, :controller => "foo", :action => "bar"}, params)
+          assert_equal({ id: nil, controller: "foo", action: "bar" }, params)
         end
       end
 
       def test_recognize_with_unbound_regexp
         get "/foo", anchor: false, to: "foo#bar"
 
-        env = rails_env 'PATH_INFO' => '/foo/bar'
+        env = rails_env "PATH_INFO" => "/foo/bar"
 
         router.recognize(env) { |*_| }
 
-        assert_equal '/foo', env.env['SCRIPT_NAME']
-        assert_equal '/bar', env.env['PATH_INFO']
+        assert_equal "/foo", env.env["SCRIPT_NAME"]
+        assert_equal "/bar", env.env["PATH_INFO"]
       end
 
       def test_bound_regexp_keeps_path_info
         get "/foo", to: "foo#bar"
 
-        env = rails_env 'PATH_INFO' => '/foo'
+        env = rails_env "PATH_INFO" => "/foo"
 
-        before = env.env['SCRIPT_NAME']
+        before = env.env["SCRIPT_NAME"]
 
         router.recognize(env) { |*_| }
 
-        assert_equal before, env.env['SCRIPT_NAME']
-        assert_equal '/foo', env.env['PATH_INFO']
+        assert_equal before, env.env["SCRIPT_NAME"]
+        assert_equal "/foo", env.env["PATH_INFO"]
       end
 
       def test_path_not_found
@@ -172,7 +174,7 @@ module ActionDispatch
         ].each do |path|
           get path, to: "foo#bar"
         end
-        env = rails_env 'PATH_INFO' => '/messages/unknown/path'
+        env = rails_env "PATH_INFO" => "/messages/unknown/path"
         yielded = false
 
         router.recognize(env) do |*whatever|
@@ -184,33 +186,33 @@ module ActionDispatch
       def test_required_part_in_recall
         get "/messages/:a/:b", to: "foo#bar"
 
-        path, _ = @formatter.generate(nil, { :controller => "foo", :action => "bar", :a => 'a' }, { :b => 'b' })
+        path, _ = @formatter.generate(nil, { controller: "foo", action: "bar", a: "a" }, { b: "b" })
         assert_equal "/messages/a/b", path
       end
 
       def test_splat_in_recall
         get "/*path", to: "foo#bar"
 
-        path, _ = @formatter.generate(nil, { :controller => "foo", :action => "bar" }, { :path => 'b' })
+        path, _ = @formatter.generate(nil, { controller: "foo", action: "bar" }, { path: "b" })
         assert_equal "/b", path
       end
 
       def test_recall_should_be_used_when_scoring
-        get "/messages/:action(/:id(.:format))", to: 'foo#bar'
-        get "/messages/:id(.:format)", to: 'bar#baz'
+        get "/messages/:action(/:id(.:format))", to: "foo#bar"
+        get "/messages/:id(.:format)", to: "bar#baz"
 
-        path, _ = @formatter.generate(nil, { :controller => "foo", :id => 10 }, { :action => 'index' })
+        path, _ = @formatter.generate(nil, { controller: "foo", id: 10 }, { action: "index" })
         assert_equal "/messages/index/10", path
       end
 
       def test_nil_path_parts_are_ignored
         get "/:controller(/:action(.:format))", to: "tasks#lol"
 
-        params = { :controller => "tasks", :format => nil }
-        extras = { :action => 'lol' }
+        params = { controller: "tasks", format: nil }
+        extras = { action: "lol" }
 
         path, _ = @formatter.generate(nil, params, extras)
-        assert_equal '/tasks', path
+        assert_equal "/tasks", path
       end
 
       def test_generate_slash
@@ -219,11 +221,11 @@ module ActionDispatch
         get "/", Hash[params]
 
         path, _ = @formatter.generate(nil, Hash[params], {})
-        assert_equal '/', path
+        assert_equal "/", path
       end
 
       def test_generate_calls_param_proc
-        get '/:controller(/:action)', to: "foo#bar"
+        get "/:controller(/:action)", to: "foo#bar"
 
         parameterized = []
         params = [ [:controller, "tasks"],
@@ -233,71 +235,71 @@ module ActionDispatch
           nil,
           Hash[params],
           {},
-          lambda { |k,v| parameterized << [k,v]; v })
+          lambda { |k, v| parameterized << [k, v]; v })
 
         assert_equal params.map(&:to_s).sort, parameterized.map(&:to_s).sort
       end
 
       def test_generate_id
-        get '/:controller(/:action)', to: 'foo#bar'
+        get "/:controller(/:action)", to: "foo#bar"
 
         path, params = @formatter.generate(
-          nil, {:id=>1, :controller=>"tasks", :action=>"show"}, {})
-        assert_equal '/tasks/show', path
-        assert_equal({:id => 1}, params)
+          nil, { id: 1, controller: "tasks", action: "show" }, {})
+        assert_equal "/tasks/show", path
+        assert_equal({ id: 1 }, params)
       end
 
       def test_generate_escapes
-        get '/:controller(/:action)', to: "foo#bar"
+        get "/:controller(/:action)", to: "foo#bar"
 
         path, _ = @formatter.generate(nil,
-          { :controller        => "tasks",
-                 :action            => "a/b c+d",
+          { controller: "tasks",
+                 action: "a/b c+d",
         }, {})
-        assert_equal '/tasks/a%2Fb%20c+d', path
+        assert_equal "/tasks/a%2Fb%20c+d", path
       end
 
       def test_generate_escapes_with_namespaced_controller
-        get '/:controller(/:action)', to: "foo#bar"
+        get "/:controller(/:action)", to: "foo#bar"
 
         path, _ = @formatter.generate(
-          nil, { :controller        => "admin/tasks",
-                 :action            => "a/b c+d",
+          nil, { controller: "admin/tasks",
+                 action: "a/b c+d",
         }, {})
-        assert_equal '/admin/tasks/a%2Fb%20c+d', path
+        assert_equal "/admin/tasks/a%2Fb%20c+d", path
       end
 
       def test_generate_extra_params
-        get '/:controller(/:action)', to: "foo#bar"
+        get "/:controller(/:action)", to: "foo#bar"
 
         path, params = @formatter.generate(
-          nil, { :id                => 1,
-                 :controller        => "tasks",
-                 :action            => "show",
-                 :relative_url_root => nil
+          nil, { id: 1,
+                 controller: "tasks",
+                 action: "show",
+                 relative_url_root: nil
         }, {})
-        assert_equal '/tasks/show', path
-        assert_equal({:id => 1, :relative_url_root => nil}, params)
+        assert_equal "/tasks/show", path
+        assert_equal({ id: 1, relative_url_root: nil }, params)
       end
 
       def test_generate_missing_keys_no_matches_different_format_keys
-        get '/:controller/:action/:name', to: "foo#bar"
+        get "/:controller/:action/:name", to: "foo#bar"
         primarty_parameters = {
-          :id                => 1,
-          :controller        => "tasks",
-          :action            => "show",
-          :relative_url_root => nil
+          id: 1,
+          controller: "tasks",
+          action: "show",
+          relative_url_root: nil
         }
         redirection_parameters = {
-          'action'=>'show',
+          "action" => "show",
         }
-        missing_key = 'name'
-        missing_parameters ={
+        missing_key = "name"
+        missing_parameters = {
           missing_key => "task_1"
         }
         request_parameters = primarty_parameters.merge(redirection_parameters).merge(missing_parameters)
 
-        message = "No route matches #{Hash[request_parameters.sort_by{|k,v|k.to_s}].inspect} missing required keys: #{[missing_key.to_sym].inspect}"
+        message = "No route matches #{Hash[request_parameters.sort_by { |k, v|k.to_s }].inspect}, missing required keys: #{[missing_key.to_sym].inspect}"
 
         error = assert_raises(ActionController::UrlGenerationError) do
           @formatter.generate(
@@ -307,42 +309,42 @@ module ActionDispatch
       end
 
       def test_generate_uses_recall_if_needed
-        get '/:controller(/:action(/:id))', to: "foo#bar"
+        get "/:controller(/:action(/:id))", to: "foo#bar"
 
         path, params = @formatter.generate(
           nil,
-          {:controller =>"tasks", :id => 10},
-          {:action     =>"index"})
-        assert_equal '/tasks/index/10', path
+          { controller: "tasks", id: 10 },
+          { action: "index" })
+        assert_equal "/tasks/index/10", path
         assert_equal({}, params)
       end
 
       def test_generate_with_name
-        get '/:controller(/:action)', to: 'foo#bar', as: 'tasks'
+        get "/:controller(/:action)", to: "foo#bar", as: "tasks"
 
         path, params = @formatter.generate(
           "tasks",
-          {:controller=>"tasks"},
-          {:controller=>"tasks", :action=>"index"})
-        assert_equal '/tasks', path
+          { controller: "tasks" },
+          { controller: "tasks", action: "index" })
+        assert_equal "/tasks", path
         assert_equal({}, params)
       end
 
       {
-        '/content'          => { :controller => 'content' },
-        '/content/list'     => { :controller => 'content', :action => 'list' },
-        '/content/show/10'  => { :controller => 'content', :action => 'show', :id => "10" },
+        "/content"          => { controller: "content" },
+        "/content/list"     => { controller: "content", action: "list" },
+        "/content/show/10"  => { controller: "content", action: "show", id: "10" },
       }.each do |request_path, expected|
         define_method("test_recognize_#{expected.keys.map(&:to_s).join('_')}") do
-          get "/:controller(/:action(/:id))", to: 'foo#bar'
+          get "/:controller(/:action(/:id))", to: "foo#bar"
           route = @routes.first
 
-          env = rails_env 'PATH_INFO' => request_path
-          called   = false
+          env = rails_env "PATH_INFO" => request_path
+          called = false
 
           router.recognize(env) do |r, params|
             assert_equal route, r
-            assert_equal({ :action => "bar" }.merge(expected), params)
+            assert_equal({ action: "bar" }.merge(expected), params)
             called = true
           end
 
@@ -351,19 +353,19 @@ module ActionDispatch
       end
 
       {
-        :segment => ['/a%2Fb%20c+d/splat', { :segment => 'a/b c+d', :splat => 'splat'   }],
-        :splat   => ['/segment/a/b%20c+d', { :segment => 'segment', :splat => 'a/b c+d' }]
+        segment: ["/a%2Fb%20c+d/splat", { segment: "a/b c+d", splat: "splat"   }],
+        splat: ["/segment/a/b%20c+d", { segment: "segment", splat: "a/b c+d" }]
       }.each do |name, (request_path, expected)|
         define_method("test_recognize_#{name}") do
-          get '/:segment/*splat', to: 'foo#bar'
+          get "/:segment/*splat", to: "foo#bar"
 
-          env = rails_env 'PATH_INFO' => request_path
-          called   = false
+          env = rails_env "PATH_INFO" => request_path
+          called = false
           route = @routes.first
 
           router.recognize(env) do |r, params|
             assert_equal route, r
-            assert_equal(expected.merge(:controller=>"foo", :action=>"bar"), params)
+            assert_equal(expected.merge(controller: "foo", action: "bar"), params)
             called = true
           end
 
@@ -372,15 +374,15 @@ module ActionDispatch
       end
 
       def test_namespaced_controller
-        get "/:controller(/:action(/:id))", { :controller => /.+?/ }
+        get "/:controller(/:action(/:id))", controller: /.+?/
         route = @routes.first
 
-        env = rails_env 'PATH_INFO' => '/admin/users/show/10'
+        env = rails_env "PATH_INFO" => "/admin/users/show/10"
         called   = false
         expected = {
-          :controller => 'admin/users',
-          :action     => 'show',
-          :id         => '10'
+          controller: "admin/users",
+          action: "show",
+          id: "10"
         }
 
         router.recognize(env) do |r, params|
@@ -395,8 +397,8 @@ module ActionDispatch
         get "/books(/:action(.:format))", controller: "books"
         route = @routes.first
 
-        env    = rails_env 'PATH_INFO' => '/books/list.rss'
-        expected = { :controller => 'books', :action => 'list', :format => 'rss' }
+        env = rails_env "PATH_INFO" => "/books/list.rss"
+        expected = { controller: "books", action: "list", format: "rss" }
         called = false
         router.recognize(env) do |r, params|
           assert_equal route, r
@@ -408,11 +410,11 @@ module ActionDispatch
       end
 
       def test_recognize_head_route
-        match "/books(/:action(.:format))", via: 'head', to: 'foo#bar'
+        match "/books(/:action(.:format))", via: "head", to: "foo#bar"
 
         env = rails_env(
-          'PATH_INFO' => '/books/list.rss',
-          'REQUEST_METHOD' => 'HEAD'
+          "PATH_INFO" => "/books/list.rss",
+          "REQUEST_METHOD" => "HEAD"
         )
 
         called = false
@@ -424,10 +426,10 @@ module ActionDispatch
       end
 
       def test_recognize_head_request_as_get_route
-        get "/books(/:action(.:format))", to: 'foo#bar'
+        get "/books(/:action(.:format))", to: "foo#bar"
 
-        env = rails_env 'PATH_INFO' => '/books/list.rss',
-                        "REQUEST_METHOD"    => "HEAD"
+        env = rails_env "PATH_INFO" => "/books/list.rss",
+                        "REQUEST_METHOD" => "HEAD"
 
         called = false
         router.recognize(env) do |r, params|
@@ -440,7 +442,7 @@ module ActionDispatch
       def test_recognize_cares_about_get_verbs
         match "/books(/:action(.:format))", to: "foo#bar", via: :get
 
-        env = rails_env 'PATH_INFO' => '/books/list.rss',
+        env = rails_env "PATH_INFO" => "/books/list.rss",
                         "REQUEST_METHOD" => "POST"
 
         called = false
@@ -454,7 +456,7 @@ module ActionDispatch
       def test_recognize_cares_about_post_verbs
         match "/books(/:action(.:format))", to: "foo#bar", via: :post
 
-        env = rails_env 'PATH_INFO' => '/books/list.rss',
+        env = rails_env "PATH_INFO" => "/books/list.rss",
                         "REQUEST_METHOD" => "POST"
 
         called = false
@@ -469,7 +471,7 @@ module ActionDispatch
         match "/books(/:action(.:format))", to: "foo#bar", via: [:post, :get]
 
         %w( POST GET ).each do |verb|
-          env = rails_env 'PATH_INFO' => '/books/list.rss',
+          env = rails_env "PATH_INFO" => "/books/list.rss",
             "REQUEST_METHOD" => verb
 
           called = false
@@ -480,8 +482,8 @@ module ActionDispatch
           assert called
         end
 
-        env = rails_env 'PATH_INFO' => '/books/list.rss',
-          "REQUEST_METHOD" => 'PUT'
+        env = rails_env "PATH_INFO" => "/books/list.rss",
+          "REQUEST_METHOD" => "PUT"
 
         called = false
         router.recognize(env) do |r, params|
@@ -493,41 +495,41 @@ module ActionDispatch
 
       private
 
-      def get *args
-        ActiveSupport::Deprecation.silence do
-          mapper.get(*args)
+        def get(*args)
+          ActiveSupport::Deprecation.silence do
+            mapper.get(*args)
+          end
         end
-      end
 
-      def match *args
-        ActiveSupport::Deprecation.silence do
-          mapper.match(*args)
+        def match(*args)
+          ActiveSupport::Deprecation.silence do
+            mapper.match(*args)
+          end
         end
-      end
 
-      def rails_env env, klass = ActionDispatch::Request
-        klass.new(rack_env(env))
-      end
-
-      def rack_env env
-        {
-          "rack.version"      => [1, 1],
-          "rack.input"        => StringIO.new,
-          "rack.errors"       => StringIO.new,
-          "rack.multithread"  => true,
-          "rack.multiprocess" => true,
-          "rack.run_once"     => false,
-          "REQUEST_METHOD"    => "GET",
-          "SERVER_NAME"       => "example.org",
-          "SERVER_PORT"       => "80",
-          "QUERY_STRING"      => "",
-          "PATH_INFO"         => "/content",
-          "rack.url_scheme"   => "http",
-          "HTTPS"             => "off",
-          "SCRIPT_NAME"       => "",
-          "CONTENT_LENGTH"    => "0"
-        }.merge env
-      end
+        def rails_env(env, klass = ActionDispatch::Request)
+          klass.new(rack_env(env))
+        end
+
+        def rack_env(env)
+          {
+            "rack.version"      => [1, 1],
+            "rack.input"        => StringIO.new,
+            "rack.errors"       => StringIO.new,
+            "rack.multithread"  => true,
+            "rack.multiprocess" => true,
+            "rack.run_once"     => false,
+            "REQUEST_METHOD"    => "GET",
+            "SERVER_NAME"       => "example.org",
+            "SERVER_PORT"       => "80",
+            "QUERY_STRING"      => "",
+            "PATH_INFO"         => "/content",
+            "rack.url_scheme"   => "http",
+            "HTTPS"             => "off",
+            "SCRIPT_NAME"       => "",
+            "CONTENT_LENGTH"    => "0"
+          }.merge env
+        end
     end
   end
 end
diff --git a/actionpack/test/journey/routes_test.rb b/actionpack/test/journey/routes_test.rb
index f8293dfc5f..81ce07526f 100644
--- a/actionpack/test/journey/routes_test.rb
+++ b/actionpack/test/journey/routes_test.rb
@@ -1,4 +1,6 @@
-require 'abstract_unit'
+# frozen_string_literal: true
+
+require "abstract_unit"
 
 module ActionDispatch
   module Journey
@@ -6,7 +8,7 @@ module ActionDispatch
       attr_reader :routes, :mapper
 
       def setup
-        @route_set  = ActionDispatch::Routing::RouteSet.new
+        @route_set = ActionDispatch::Routing::RouteSet.new
         @routes = @route_set.router.routes
         @router = @route_set.router
         @mapper = ActionDispatch::Routing::Mapper.new @route_set
@@ -14,7 +16,7 @@ module ActionDispatch
       end
 
       def test_clear
-        mapper.get "/foo(/:id)", to: "foo#bar", as: 'aaron'
+        mapper.get "/foo(/:id)", to: "foo#bar", as: "aaron"
         assert_not_predicate routes, :empty?
         assert_equal 1, routes.length
 
@@ -24,35 +26,35 @@ module ActionDispatch
       end
 
       def test_ast
-        mapper.get "/foo(/:id)", to: "foo#bar", as: 'aaron'
+        mapper.get "/foo(/:id)", to: "foo#bar", as: "aaron"
         ast = routes.ast
-        mapper.get "/foo(/:id)", to: "foo#bar", as: 'gorby'
+        mapper.get "/foo(/:id)", to: "foo#bar", as: "gorby"
         assert_not_equal ast, routes.ast
       end
 
       def test_simulator_changes
-        mapper.get "/foo(/:id)", to: "foo#bar", as: 'aaron'
+        mapper.get "/foo(/:id)", to: "foo#bar", as: "aaron"
         sim = routes.simulator
-        mapper.get "/foo(/:id)", to: "foo#bar", as: 'gorby'
+        mapper.get "/foo(/:id)", to: "foo#bar", as: "gorby"
         assert_not_equal sim, routes.simulator
       end
 
       def test_partition_route
-        mapper.get "/foo(/:id)", to: "foo#bar", as: 'aaron'
+        mapper.get "/foo(/:id)", to: "foo#bar", as: "aaron"
 
         assert_equal 1, @routes.anchored_routes.length
         assert_predicate @routes.custom_routes, :empty?
 
-        mapper.get "/hello/:who", to: "foo#bar", as: 'bar', who: /\d/
+        mapper.get "/hello/:who", to: "foo#bar", as: "bar", who: /\d/
 
         assert_equal 1, @routes.custom_routes.length
         assert_equal 1, @routes.anchored_routes.length
       end
 
       def test_first_name_wins
-        mapper.get "/hello", to: "foo#bar", as: 'aaron'
+        mapper.get "/hello", to: "foo#bar", as: "aaron"
         assert_raise(ArgumentError) do
-          mapper.get "/aaron", to: "foo#bar", as: 'aaron'
+          mapper.get "/aaron", to: "foo#bar", as: "aaron"
         end
       end
     end
diff --git a/actionpack/test/lib/controller/fake_controllers.rb b/actionpack/test/lib/controller/fake_controllers.rb
index 1a2863b689..e985716f43 100644
--- a/actionpack/test/lib/controller/fake_controllers.rb
+++ b/actionpack/test/lib/controller/fake_controllers.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class ContentController < ActionController::Base; end
 
 module Admin
diff --git a/actionpack/test/lib/controller/fake_models.rb b/actionpack/test/lib/controller/fake_models.rb
index ce9522d12a..01c7ec26ae 100644
--- a/actionpack/test/lib/controller/fake_models.rb
+++ b/actionpack/test/lib/controller/fake_models.rb
@@ -1,12 +1,14 @@
+# frozen_string_literal: true
+
 require "active_model"
 
-class Customer < Struct.new(:name, :id)
+Customer = Struct.new(:name, :id) do
   extend ActiveModel::Naming
   include ActiveModel::Conversion
 
   undef_method :to_json
 
-  def to_xml(options={})
+  def to_xml(options = {})
     if options[:builder]
       options[:builder].name name
     else
@@ -14,7 +16,7 @@ class Customer < Struct.new(:name, :id)
     end
   end
 
-  def to_js(options={})
+  def to_js(options = {})
     "name: #{name.inspect}"
   end
   alias :to_text :to_js
@@ -26,9 +28,13 @@ class Customer < Struct.new(:name, :id)
   def persisted?
     id.present?
   end
+
+  def cache_key
+    "#{name}/#{id}"
+  end
 end
 
-class Post < Struct.new(:title, :author_name, :body, :secret, :persisted, :written_on, :cost)
+Post = Struct.new(:title, :author_name, :body, :secret, :persisted, :written_on, :cost) do
   extend ActiveModel::Naming
   include ActiveModel::Conversion
   extend ActiveModel::Translation
diff --git a/actionpack/test/routing/helper_test.rb b/actionpack/test/routing/helper_test.rb
index 0028aaa629..d13b043b0b 100644
--- a/actionpack/test/routing/helper_test.rb
+++ b/actionpack/test/routing/helper_test.rb
@@ -1,4 +1,6 @@
-require 'abstract_unit'
+# frozen_string_literal: true
+
+require "abstract_unit"
 
 module ActionDispatch
   module Routing
diff --git a/actionview/.gitignore b/actionview/.gitignore
new file mode 100644
index 0000000000..0a04b29786
--- /dev/null
+++ b/actionview/.gitignore
@@ -0,0 +1,2 @@
+/lib/assets/compiled
+/tmp
diff --git a/actionview/CHANGELOG.md b/actionview/CHANGELOG.md
index 9d669c7cd8..c38e11dc38 100644
--- a/actionview/CHANGELOG.md
+++ b/actionview/CHANGELOG.md
@@ -1,19 +1,79 @@
-*   `select_tag`'s `include_blank` option for generation for blank option tag, now adds an empty space label,
-     when the value as well as content for option tag are empty, so that we confirm with html specification.
-     Ref: https://www.w3.org/TR/html5/forms.html#the-option-element.
+*   Allow the use of callable objects as group methods for grouped selects.
 
-    Generation of option before:
+    Until now, the `option_groups_from_collection_for_select` method was only able to
+    handle method names as `group_method` and `group_label_method` parameters,
+    it is now able to receive procs and other callable objects too.
 
-    ```html
-    <option value=""></option>
-    ```
+    *Jérémie Bonal*
 
-    Generation of option after:
+*   Add `preload_link_tag` helper
 
-    ```html
-    <option value="" label=" "></option>
-    ```
+    This helper that allows to the browser to initiate early fetch of resources
+    (different to the specified in `javascript_include_tag` and `stylesheet_link_tag`).
+    Additionally, this sends Early Hints if supported by browser.
 
-    *Vipul A M*
+    *Guillermo Iguaran*
 
-Please check [5-0-stable](https://github.com/rails/rails/blob/5-0-stable/actionview/CHANGELOG.md) for previous changes.
+## Rails 5.2.0.beta2 (November 28, 2017) ##
+
+*   No changes.
+
+
+## Rails 5.2.0.beta1 (November 27, 2017) ##
+
+*   Change `form_with` to generates ids by default.
+
+    When `form_with` was introduced we disabled the automatic generation of ids
+    that was enabled in `form_for`. This usually is not an good idea since labels don't work
+    when the input doesn't have an id and it made harder to test with Capybara.
+
+    You can still disable the automatic generation of ids setting `config.action_view.form_with_generates_ids`
+    to `false.`
+
+    *Nick Pezza*
+
+*   Fix issues with `field_error_proc` wrapping `optgroup` and select divider `option`.
+
+    Fixes #31088
+
+    *Matthias Neumayr*
+
+*   Remove deprecated Erubis ERB handler.
+
+    *Rafael Mendonça França*
+
+*   Remove default `alt` text generation.
+
+    Fixes #30096
+
+    *Cameron Cundiff*
+
+*   Add `srcset` option to `image_tag` helper.
+
+    *Roberto Miranda*
+
+*   Fix issues with scopes and engine on `current_page?` method.
+
+    Fixes #29401.
+
+    *Nikita Savrov*
+
+*   Generate field ids in `collection_check_boxes` and `collection_radio_buttons`.
+
+    This makes sure that the labels are linked up with the fields.
+
+    Fixes #29014.
+
+    *Yuji Yaginuma*
+
+*   Add `:json` type to `auto_discovery_link_tag` to support [JSON Feeds](https://jsonfeed.org/version/1)
+
+    *Mike Gunderloy*
+
+*   Update `distance_of_time_in_words` helper to display better error messages
+    for bad input.
+
+    *Jay Hayes*
+
+
+Please check [5-1-stable](https://github.com/rails/rails/blob/5-1-stable/actionview/CHANGELOG.md) for previous changes.
diff --git a/actionview/MIT-LICENSE b/actionview/MIT-LICENSE
index 8573eb1225..1cb3add0fc 100644
--- a/actionview/MIT-LICENSE
+++ b/actionview/MIT-LICENSE
@@ -1,4 +1,4 @@
-Copyright (c) 2004-2016 David Heinemeier Hansson
+Copyright (c) 2004-2018 David Heinemeier Hansson
 
 Permission is hereby granted, free of charge, to any person obtaining
 a copy of this software and associated documentation files (the
diff --git a/actionview/README.rdoc b/actionview/README.rdoc
index 7a3e5e31d0..03a0723564 100644
--- a/actionview/README.rdoc
+++ b/actionview/README.rdoc
@@ -11,7 +11,7 @@ The latest version of Action View can be installed with RubyGems:
 
   $ gem install actionview
 
-Source code can be downloaded as part of the Rails project on GitHub
+Source code can be downloaded as part of the Rails project on GitHub:
 
 * https://github.com/rails/rails/tree/master/actionview
 
@@ -20,7 +20,7 @@ Source code can be downloaded as part of the Rails project on GitHub
 
 Action View is released under the MIT license:
 
-* http://www.opensource.org/licenses/MIT
+* https://opensource.org/licenses/MIT
 
 
 == Support
@@ -29,7 +29,7 @@ API documentation is at
 
 * http://api.rubyonrails.org
 
-Bug reports can be filed for the Ruby on Rails project here:
+Bug reports for the Ruby on Rails project can be filed here:
 
 * https://github.com/rails/rails/issues
 
diff --git a/actionview/RUNNING_UJS_TESTS.rdoc b/actionview/RUNNING_UJS_TESTS.rdoc
new file mode 100644
index 0000000000..e30c2aee55
--- /dev/null
+++ b/actionview/RUNNING_UJS_TESTS.rdoc
@@ -0,0 +1,8 @@
+== Running UJS tests
+
+Ensure that you can build the project by running:
+   rake ujs:server
+
+Then run the web tests by visiting the following URL in your browser:
+
+   http://localhost:4567
diff --git a/actionview/RUNNING_UNIT_TESTS.rdoc b/actionview/RUNNING_UNIT_TESTS.rdoc
index 6c4e5e983a..4442dbdb9e 100644
--- a/actionview/RUNNING_UNIT_TESTS.rdoc
+++ b/actionview/RUNNING_UNIT_TESTS.rdoc
@@ -2,13 +2,13 @@
 
 The easiest way to run the unit tests is through Rake. The default task runs
 the entire test suite for all classes. For more information, checkout the
-full array of rake tasks with "rake -T"
+full array of rake tasks with <tt>rake -T</tt>
 
-Rake can be found at http://docs.seattlerb.org/rake/.
+Rake can be found at https://ruby.github.io/rake/.
 
 == Running by hand
 
-To run a single test suite
+Run a single test suite:
 
    rake test TEST=path/to/test.rb
 
@@ -18,10 +18,9 @@ which can be further narrowed down to one test:
 
 == Dependency on Active Record and database setup
 
-Test cases in the test/activerecord/ directory depend on having
-activerecord and sqlite3 installed. If Active Record is not in
-actionview/../activerecord directory, or the sqlite3 rubygem is not installed,
-these tests are skipped.
-
+Test cases in the +test/activerecord/+ directory depend on having
+activerecord+ and +sqlite3+ installed. If Active Record is not in
+actionview/../activerecord+ directory, or the +sqlite3+ Ruby gem is not installed,
+  these tests are skipped.
 Other tests are runnable from a fresh copy of actionview without any configuration.
 
diff --git a/actionview/Rakefile b/actionview/Rakefile
index f0f9bda3e4..8650f541b0 100644
--- a/actionview/Rakefile
+++ b/actionview/Rakefile
@@ -1,43 +1,73 @@
-require 'rake/testtask'
+# frozen_string_literal: true
+
+require "rake/testtask"
+require "fileutils"
+require "open3"
 
 desc "Default Task"
-task :default => :test
+task default: :test
 
-task :package
+task package: %w( assets:compile assets:verify )
 
 # Run the unit tests
 
 desc "Run all unit tests"
-task :test => ["test:template", "test:integration:action_pack", "test:integration:active_record"]
+task test: ["test:template", "test:integration:action_pack", "test:integration:active_record"]
 
 namespace :test do
   task :isolated do
     Dir.glob("test/{actionpack,activerecord,template}/**/*_test.rb").all? do |file|
-      sh(Gem.ruby, '-w', '-Ilib:test', file)
-    end or raise "Failures"
+      sh(Gem.ruby, "-w", "-Ilib:test", file)
+    end || raise("Failures")
   end
 
   Rake::TestTask.new(:template) do |t|
-    t.libs << 'test'
-    t.test_files = Dir.glob('test/template/**/*_test.rb')
+    t.libs << "test"
+    t.test_files = Dir.glob("test/template/**/*_test.rb")
     t.warning = true
     t.verbose = true
     t.ruby_opts = ["--dev"] if defined?(JRUBY_VERSION)
   end
 
+  task :ujs do
+    begin
+      Dir.mkdir("log")
+      pid = spawn("bundle exec rackup test/ujs/config.ru -p 4567 -s puma > log/test.log 2>&1", pgroup: true)
+
+      start_time = Time.now
+
+      loop do
+        break if system("lsof -i :4567", 1 => File::NULL)
+
+        if Time.now - start_time > 5
+          puts "Timed out after 5 seconds"
+          exit 1
+        end
+      end
+
+      system("npm run lint && bundle exec ruby ../ci/qunit-selenium-runner.rb http://localhost:4567/")
+      status = $?.exitstatus
+    ensure
+      Process.kill("KILL", -pid) if pid
+      FileUtils.rm_rf("log")
+    end
+
+    exit status
+  end
+
   namespace :integration do
-    desc 'ActiveRecord Integration Tests'
+    desc "ActiveRecord Integration Tests"
     Rake::TestTask.new(:active_record) do |t|
-      t.libs << 'test'
+      t.libs << "test"
       t.test_files = Dir.glob("test/activerecord/*_test.rb")
       t.warning = true
       t.verbose = true
       t.ruby_opts = ["--dev"] if defined?(JRUBY_VERSION)
     end
 
-    desc 'ActionPack Integration Tests'
+    desc "ActionPack Integration Tests"
     Rake::TestTask.new(:action_pack) do |t|
-      t.libs << 'test'
+      t.libs << "test"
       t.test_files = Dir.glob("test/actionpack/**/*_test.rb")
       t.warning = true
       t.verbose = true
@@ -46,8 +76,61 @@ namespace :test do
   end
 end
 
+namespace :ujs do
+  desc "Starts the test server"
+  task :server do
+    system "bundle exec rackup test/ujs/config.ru -p 4567 -s puma"
+  end
+end
+
+namespace :assets do
+  desc "Compile Action View assets"
+  task :compile do
+    require "blade"
+    require "sprockets"
+    require "sprockets/export"
+    Blade.build
+  end
+
+  desc "Verify compiled Action View assets"
+  task :verify do
+    file = "lib/assets/compiled/rails-ujs.js"
+    pathname = Pathname.new("#{__dir__}/#{file}")
+
+    print "[verify] #{file} exists "
+    if pathname.exist?
+      puts "[OK]"
+    else
+      $stderr.puts "[FAIL]"
+      fail
+    end
+
+    print "[verify] #{file} is a UMD module "
+    if pathname.read =~ /module\.exports.*define\.amd/m
+      puts "[OK]"
+    else
+      $stderr.puts "[FAIL]"
+      fail
+    end
+
+    print "[verify] #{__dir__} can be required as a module "
+    js = <<-JS
+      window = { Event: class {} }
+      class Element {}
+      require('#{__dir__}')
+    JS
+    _, stderr, status = Open3.capture3("node", "--print", js)
+    if status.success?
+      puts "[OK]"
+    else
+      $stderr.puts "[FAIL]\n#{stderr}"
+      fail
+    end
+  end
+end
+
 task :lines do
-  load File.expand_path('..', File.dirname(__FILE__)) + '/tools/line_statistics'
+  load File.join(File.expand_path("..", __dir__), "/tools/line_statistics")
   files = FileList["lib/**/*.rb"]
   CodeTools::LineStatistics.new(files).print_loc
 end
diff --git a/actionview/actionview.gemspec b/actionview/actionview.gemspec
index 75c5045ec0..b99137fcf6 100644
--- a/actionview/actionview.gemspec
+++ b/actionview/actionview.gemspec
@@ -1,31 +1,38 @@
-version = File.read(File.expand_path("../../RAILS_VERSION", __FILE__)).strip
+# frozen_string_literal: true
+
+version = File.read(File.expand_path("../RAILS_VERSION", __dir__)).strip
 
 Gem::Specification.new do |s|
   s.platform    = Gem::Platform::RUBY
-  s.name        = 'actionview'
+  s.name        = "actionview"
   s.version     = version
-  s.summary     = 'Rendering framework putting the V in MVC (part of Rails).'
-  s.description = 'Simple, battle-tested conventions and helpers for building web pages.'
+  s.summary     = "Rendering framework putting the V in MVC (part of Rails)."
+  s.description = "Simple, battle-tested conventions and helpers for building web pages."
+
+  s.required_ruby_version = ">= 2.2.2"
 
-  s.required_ruby_version = '>= 2.2.2'
+  s.license = "MIT"
 
-  s.license = 'MIT'
+  s.author   = "David Heinemeier Hansson"
+  s.email    = "david@loudthinking.com"
+  s.homepage = "http://rubyonrails.org"
 
-  s.author   = 'David Heinemeier Hansson'
-  s.email    = 'david@loudthinking.com'
-  s.homepage = 'http://rubyonrails.org'
+  s.files        = Dir["CHANGELOG.md", "README.rdoc", "MIT-LICENSE", "lib/**/*"]
+  s.require_path = "lib"
+  s.requirements << "none"
 
-  s.files        = Dir['CHANGELOG.md', 'README.rdoc', 'MIT-LICENSE', 'lib/**/*']
-  s.require_path = 'lib'
-  s.requirements << 'none'
+  s.metadata = {
+    "source_code_uri" => "https://github.com/rails/rails/tree/v#{version}/actionview",
+    "changelog_uri"   => "https://github.com/rails/rails/blob/v#{version}/actionview/CHANGELOG.md"
+  }
 
-  s.add_dependency 'activesupport', version
+  s.add_dependency "activesupport", version
 
-  s.add_dependency 'builder',       '~> 3.1'
-  s.add_dependency 'erubis',        '~> 2.7.0'
-  s.add_dependency 'rails-html-sanitizer', '~> 1.0', '>= 1.0.2'
-  s.add_dependency 'rails-dom-testing', '~> 2.0'
+  s.add_dependency "builder",       "~> 3.1"
+  s.add_dependency "erubi",         "~> 1.4"
+  s.add_dependency "rails-html-sanitizer", "~> 1.0", ">= 1.0.3"
+  s.add_dependency "rails-dom-testing", "~> 2.0"
 
-  s.add_development_dependency 'actionpack',  version
-  s.add_development_dependency 'activemodel', version
+  s.add_development_dependency "actionpack",  version
+  s.add_development_dependency "activemodel", version
 end
diff --git a/actionview/app/assets/javascripts/MIT-LICENSE b/actionview/app/assets/javascripts/MIT-LICENSE
new file mode 100644
index 0000000000..28e1b12496
--- /dev/null
+++ b/actionview/app/assets/javascripts/MIT-LICENSE
@@ -0,0 +1,20 @@
+Copyright (c) 2007-2018 Rails Core team
+
+Permission is hereby granted, free of charge, to any person obtaining
+a copy of this software and associated documentation files (the
+"Software"), to deal in the Software without restriction, including
+without limitation the rights to use, copy, modify, merge, publish,
+distribute, sublicense, and/or sell copies of the Software, and to
+permit persons to whom the Software is furnished to do so, subject to
+the following conditions:
+
+The above copyright notice and this permission notice shall be
+included in all copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
+LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
+OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
diff --git a/actionview/app/assets/javascripts/README.md b/actionview/app/assets/javascripts/README.md
new file mode 100644
index 0000000000..8198011b02
--- /dev/null
+++ b/actionview/app/assets/javascripts/README.md
@@ -0,0 +1,55 @@
+# Ruby on Rails unobtrusive scripting adapter
+
+This unobtrusive scripting support file is developed for the Ruby on Rails framework, but is not strictly tied to any specific backend. You can drop this into any application to:
+
+- force confirmation dialogs for various actions;
+- make non-GET requests from hyperlinks;
+- make forms or hyperlinks submit data asynchronously with Ajax;
+- have submit buttons become automatically disabled on form submit to prevent double-clicking.
+
+These features are achieved by adding certain [`data` attributes][data] to your HTML markup. In Rails, they are added by the framework's template helpers.
+
+## Optional prerequisites
+
+Note that the `data` attributes this library adds are a feature of HTML5. If you're not targeting HTML5, these attributes may make your HTML to fail [validation][validator]. However, this shouldn't create any issues for web browsers or other user agents.
+
+## Installation
+
+### NPM
+
+    npm install rails-ujs --save
+    
+### Yarn
+    
+    yarn add rails-ujs
+
+## Usage
+
+### Asset pipeline
+
+In a conventional Rails application that uses the asset pipeline, require `rails-ujs` in your `application.js` manifest:
+
+```javascript
+//= require rails-ujs
+```
+
+### ES2015+
+
+If you're using the Webpacker gem or some other JavaScript bundler, add the following to your main JS file:
+
+```javascript
+import Rails from 'rails-ujs';
+Rails.start()
+```
+
+## How to run tests
+
+Run `bundle exec rake ujs:server` first, and then run the web tests by visiting http://localhost:4567 in your browser.
+
+## License
+
+rails-ujs is released under the [MIT License](MIT-LICENSE).
+
+[data]: http://www.w3.org/TR/html5/dom.html#embedding-custom-non-visible-data-with-the-data-*-attributes "Embedding custom non-visible data with the data-* attributes"
+[validator]: http://validator.w3.org/
+[csrf]: http://api.rubyonrails.org/classes/ActionController/RequestForgeryProtection.html
diff --git a/actionview/app/assets/javascripts/rails-ujs.coffee b/actionview/app/assets/javascripts/rails-ujs.coffee
new file mode 100644
index 0000000000..bd6e9bb881
--- /dev/null
+++ b/actionview/app/assets/javascripts/rails-ujs.coffee
@@ -0,0 +1,39 @@
+#= require ./rails-ujs/BANNER
+#= export Rails
+#= require_self
+#= require_tree ./rails-ujs/utils
+#= require_tree ./rails-ujs/features
+#= require ./rails-ujs/start
+
+@Rails =
+  # Link elements bound by rails-ujs
+  linkClickSelector: 'a[data-confirm], a[data-method], a[data-remote]:not([disabled]), a[data-disable-with], a[data-disable]'
+
+  # Button elements bound by rails-ujs
+  buttonClickSelector:
+    selector: 'button[data-remote]:not([form]), button[data-confirm]:not([form])'
+    exclude: 'form button'
+
+  # Select elements bound by rails-ujs
+  inputChangeSelector: 'select[data-remote], input[data-remote], textarea[data-remote]'
+
+  # Form elements bound by rails-ujs
+  formSubmitSelector: 'form'
+
+  # Form input elements bound by rails-ujs
+  formInputClickSelector: 'form input[type=submit], form input[type=image], form button[type=submit], form button:not([type]), input[type=submit][form], input[type=image][form], button[type=submit][form], button[form]:not([type])'
+
+  # Form input elements disabled during form submission
+  formDisableSelector: 'input[data-disable-with]:enabled, button[data-disable-with]:enabled, textarea[data-disable-with]:enabled, input[data-disable]:enabled, button[data-disable]:enabled, textarea[data-disable]:enabled'
+
+  # Form input elements re-enabled after form submission
+  formEnableSelector: 'input[data-disable-with]:disabled, button[data-disable-with]:disabled, textarea[data-disable-with]:disabled, input[data-disable]:disabled, button[data-disable]:disabled, textarea[data-disable]:disabled'
+
+  # Form file input elements
+  fileInputSelector: 'input[name][type=file]:not([disabled])'
+
+  # Link onClick disable selector with possible reenable after remote submission
+  linkDisableSelector: 'a[data-disable-with], a[data-disable]'
+
+  # Button onClick disable selector with possible reenable after remote submission
+  buttonDisableSelector: 'button[data-remote][data-disable-with], button[data-remote][data-disable]'
diff --git a/actionview/app/assets/javascripts/rails-ujs/BANNER.js b/actionview/app/assets/javascripts/rails-ujs/BANNER.js
new file mode 100644
index 0000000000..47ecd66003
--- /dev/null
+++ b/actionview/app/assets/javascripts/rails-ujs/BANNER.js
@@ -0,0 +1,5 @@
+/*
+Unobtrusive JavaScript
+https://github.com/rails/rails/blob/master/actionview/app/assets/javascripts
+Released under the MIT license
+ */
diff --git a/actionview/app/assets/javascripts/rails-ujs/features/confirm.coffee b/actionview/app/assets/javascripts/rails-ujs/features/confirm.coffee
new file mode 100644
index 0000000000..72b5aaa218
--- /dev/null
+++ b/actionview/app/assets/javascripts/rails-ujs/features/confirm.coffee
@@ -0,0 +1,26 @@
+#= require_tree ../utils
+
+{ fire, stopEverything } = Rails
+
+Rails.handleConfirm = (e) ->
+  stopEverything(e) unless allowAction(this)
+
+# For 'data-confirm' attribute:
+# - Fires `confirm` event
+# - Shows the confirmation dialog
+# - Fires the `confirm:complete` event
+#
+# Returns `true` if no function stops the chain and user chose yes `false` otherwise.
+# Attaching a handler to the element's `confirm` event that returns a `falsy` value cancels the confirmation dialog.
+# Attaching a handler to the element's `confirm:complete` event that returns a `falsy` value makes this function
+# return false. The `confirm:complete` event is fired whether or not the user answered true or false to the dialog.
+allowAction = (element) ->
+  message = element.getAttribute('data-confirm')
+  return true unless message
+
+  answer = false
+  if fire(element, 'confirm')
+    try answer = confirm(message)
+    callback = fire(element, 'confirm:complete', [answer])
+
+  answer and callback
diff --git a/actionview/app/assets/javascripts/rails-ujs/features/disable.coffee b/actionview/app/assets/javascripts/rails-ujs/features/disable.coffee
new file mode 100644
index 0000000000..90aa3bdf0e
--- /dev/null
+++ b/actionview/app/assets/javascripts/rails-ujs/features/disable.coffee
@@ -0,0 +1,82 @@
+#= require_tree ../utils
+
+{ matches, getData, setData, stopEverything, formElements } = Rails
+
+Rails.handleDisabledElement = (e) ->
+  element = this
+  stopEverything(e) if element.disabled
+
+# Unified function to enable an element (link, button and form)
+Rails.enableElement = (e) ->
+  element = if e instanceof Event then e.target else e
+  if matches(element, Rails.linkDisableSelector)
+    enableLinkElement(element)
+  else if matches(element, Rails.buttonDisableSelector) or matches(element, Rails.formEnableSelector)
+    enableFormElement(element)
+  else if matches(element, Rails.formSubmitSelector)
+    enableFormElements(element)
+
+# Unified function to disable an element (link, button and form)
+Rails.disableElement = (e) ->
+  element = if e instanceof Event then e.target else e
+  if matches(element, Rails.linkDisableSelector)
+    disableLinkElement(element)
+  else if matches(element, Rails.buttonDisableSelector) or matches(element, Rails.formDisableSelector)
+    disableFormElement(element)
+  else if matches(element, Rails.formSubmitSelector)
+    disableFormElements(element)
+
+#  Replace element's html with the 'data-disable-with' after storing original html
+#  and prevent clicking on it
+disableLinkElement = (element) ->
+  replacement = element.getAttribute('data-disable-with')
+  if replacement?
+    setData(element, 'ujs:enable-with', element.innerHTML) # store enabled state
+    element.innerHTML = replacement
+  element.addEventListener('click', stopEverything) # prevent further clicking
+  setData(element, 'ujs:disabled', true)
+
+# Restore element to its original state which was disabled by 'disableLinkElement' above
+enableLinkElement = (element) ->
+  originalText = getData(element, 'ujs:enable-with')
+  if originalText?
+    element.innerHTML = originalText # set to old enabled state
+    setData(element, 'ujs:enable-with', null) # clean up cache
+  element.removeEventListener('click', stopEverything) # enable element
+  setData(element, 'ujs:disabled', null)
+
+# Disables form elements:
+#  - Caches element value in 'ujs:enable-with' data store
+#  - Replaces element text with value of 'data-disable-with' attribute
+#  - Sets disabled property to true
+disableFormElements = (form) ->
+  formElements(form, Rails.formDisableSelector).forEach(disableFormElement)
+
+disableFormElement = (element) ->
+  replacement = element.getAttribute('data-disable-with')
+  if replacement?
+    if matches(element, 'button')
+      setData(element, 'ujs:enable-with', element.innerHTML)
+      element.innerHTML = replacement
+    else
+      setData(element, 'ujs:enable-with', element.value)
+      element.value = replacement
+  element.disabled = true
+  setData(element, 'ujs:disabled', true)
+
+# Re-enables disabled form elements:
+#  - Replaces element text with cached value from 'ujs:enable-with' data store (created in `disableFormElements`)
+#  - Sets disabled property to false
+enableFormElements = (form) ->
+  formElements(form, Rails.formEnableSelector).forEach(enableFormElement)
+
+enableFormElement = (element) ->
+  originalText = getData(element, 'ujs:enable-with')
+  if originalText?
+    if matches(element, 'button')
+      element.innerHTML = originalText
+    else
+      element.value = originalText
+    setData(element, 'ujs:enable-with', null) # clean up cache
+  element.disabled = false
+  setData(element, 'ujs:disabled', null)
diff --git a/actionview/app/assets/javascripts/rails-ujs/features/method.coffee b/actionview/app/assets/javascripts/rails-ujs/features/method.coffee
new file mode 100644
index 0000000000..d04d9414dd
--- /dev/null
+++ b/actionview/app/assets/javascripts/rails-ujs/features/method.coffee
@@ -0,0 +1,34 @@
+#= require_tree ../utils
+
+{ stopEverything } = Rails
+
+# Handles "data-method" on links such as:
+# <a href="/users/5" data-method="delete" rel="nofollow" data-confirm="Are you sure?">Delete</a>
+Rails.handleMethod = (e) ->
+  link = this
+  method = link.getAttribute('data-method')
+  return unless method
+
+  href = Rails.href(link)
+  csrfToken = Rails.csrfToken()
+  csrfParam = Rails.csrfParam()
+  form = document.createElement('form')
+  formContent = "<input name='_method' value='#{method}' type='hidden' />"
+
+  if csrfParam? and csrfToken? and not Rails.isCrossDomain(href)
+    formContent += "<input name='#{csrfParam}' value='#{csrfToken}' type='hidden' />"
+
+  # Must trigger submit by click on a button, else "submit" event handler won't work!
+  # https://developer.mozilla.org/en-US/docs/Web/API/HTMLFormElement/submit
+  formContent += '<input type="submit" />'
+
+  form.method = 'post'
+  form.action = href
+  form.target = link.target
+  form.innerHTML = formContent
+  form.style.display = 'none'
+
+  document.body.appendChild(form)
+  form.querySelector('[type="submit"]').click()
+
+  stopEverything(e)
diff --git a/actionview/app/assets/javascripts/rails-ujs/features/remote.coffee b/actionview/app/assets/javascripts/rails-ujs/features/remote.coffee
new file mode 100644
index 0000000000..b3448dabac
--- /dev/null
+++ b/actionview/app/assets/javascripts/rails-ujs/features/remote.coffee
@@ -0,0 +1,90 @@
+#= require_tree ../utils
+
+{
+  matches, getData, setData
+  fire, stopEverything
+  ajax, isCrossDomain
+  serializeElement
+} = Rails
+
+# Checks "data-remote" if true to handle the request through a XHR request.
+isRemote = (element) ->
+  value = element.getAttribute('data-remote')
+  value? and value isnt 'false'
+
+# Submits "remote" forms and links with ajax
+Rails.handleRemote = (e) ->
+  element = this
+
+  return true unless isRemote(element)
+  unless fire(element, 'ajax:before')
+    fire(element, 'ajax:stopped')
+    return false
+
+  withCredentials = element.getAttribute('data-with-credentials')
+  dataType = element.getAttribute('data-type') or 'script'
+
+  if matches(element, Rails.formSubmitSelector)
+    # memoized value from clicked submit button
+    button = getData(element, 'ujs:submit-button')
+    method = getData(element, 'ujs:submit-button-formmethod') or element.method
+    url = getData(element, 'ujs:submit-button-formaction') or element.getAttribute('action') or location.href
+
+    # strip query string if it's a GET request
+    url = url.replace(/\?.*$/, '') if method.toUpperCase() is 'GET'
+
+    if element.enctype is 'multipart/form-data'
+      data = new FormData(element)
+      data.append(button.name, button.value) if button?
+    else
+      data = serializeElement(element, button)
+
+    setData(element, 'ujs:submit-button', null)
+    setData(element, 'ujs:submit-button-formmethod', null)
+    setData(element, 'ujs:submit-button-formaction', null)
+  else if matches(element, Rails.buttonClickSelector) or matches(element, Rails.inputChangeSelector)
+    method = element.getAttribute('data-method')
+    url = element.getAttribute('data-url')
+    data = serializeElement(element, element.getAttribute('data-params'))
+  else
+    method = element.getAttribute('data-method')
+    url = Rails.href(element)
+    data = element.getAttribute('data-params')
+
+  ajax(
+    type: method or 'GET'
+    url: url
+    data: data
+    dataType: dataType
+    # stopping the "ajax:beforeSend" event will cancel the ajax request
+    beforeSend: (xhr, options) ->
+      if fire(element, 'ajax:beforeSend', [xhr, options])
+        fire(element, 'ajax:send', [xhr])
+      else
+        fire(element, 'ajax:stopped')
+        return false
+    success: (args...) -> fire(element, 'ajax:success', args)
+    error: (args...) -> fire(element, 'ajax:error', args)
+    complete: (args...) -> fire(element, 'ajax:complete', args)
+    crossDomain: isCrossDomain(url)
+    withCredentials: withCredentials? and withCredentials isnt 'false'
+  )
+  stopEverything(e)
+
+Rails.formSubmitButtonClick = (e) ->
+  button = this
+  form = button.form
+  return unless form
+  # Register the pressed submit button
+  setData(form, 'ujs:submit-button', name: button.name, value: button.value) if button.name
+  # Save attributes from button
+  setData(form, 'ujs:formnovalidate-button', button.formNoValidate)
+  setData(form, 'ujs:submit-button-formaction', button.getAttribute('formaction'))
+  setData(form, 'ujs:submit-button-formmethod', button.getAttribute('formmethod'))
+
+Rails.handleMetaClick = (e) ->
+  link = this
+  method = (link.getAttribute('data-method') or 'GET').toUpperCase()
+  data = link.getAttribute('data-params')
+  metaClick = e.metaKey or e.ctrlKey
+  e.stopImmediatePropagation() if metaClick and method is 'GET' and not data
diff --git a/actionview/app/assets/javascripts/rails-ujs/start.coffee b/actionview/app/assets/javascripts/rails-ujs/start.coffee
new file mode 100644
index 0000000000..55595ac96f
--- /dev/null
+++ b/actionview/app/assets/javascripts/rails-ujs/start.coffee
@@ -0,0 +1,70 @@
+{
+  fire, delegate
+  getData, $
+  refreshCSRFTokens, CSRFProtection
+  enableElement, disableElement, handleDisabledElement
+  handleConfirm
+  handleRemote, formSubmitButtonClick, handleMetaClick
+  handleMethod
+} = Rails
+
+# For backward compatibility
+if jQuery? and jQuery.ajax? and not jQuery.rails
+  jQuery.rails = Rails
+  jQuery.ajaxPrefilter (options, originalOptions, xhr) ->
+    CSRFProtection(xhr) unless options.crossDomain
+
+Rails.start = ->
+  # Cut down on the number of issues from people inadvertently including
+  # rails-ujs twice by detecting and raising an error when it happens.
+  throw new Error('rails-ujs has already been loaded!') if window._rails_loaded
+
+  # This event works the same as the load event, except that it fires every
+  # time the page is loaded.
+  # See https://github.com/rails/jquery-ujs/issues/357
+  # See https://developer.mozilla.org/en-US/docs/Using_Firefox_1.5_caching
+  window.addEventListener 'pageshow', ->
+    $(Rails.formEnableSelector).forEach (el) ->
+      enableElement(el) if getData(el, 'ujs:disabled')
+    $(Rails.linkDisableSelector).forEach (el) ->
+      enableElement(el) if getData(el, 'ujs:disabled')
+
+  delegate document, Rails.linkDisableSelector, 'ajax:complete', enableElement
+  delegate document, Rails.linkDisableSelector, 'ajax:stopped', enableElement
+  delegate document, Rails.buttonDisableSelector, 'ajax:complete', enableElement
+  delegate document, Rails.buttonDisableSelector, 'ajax:stopped', enableElement
+
+  delegate document, Rails.linkClickSelector, 'click', handleDisabledElement
+  delegate document, Rails.linkClickSelector, 'click', handleConfirm
+  delegate document, Rails.linkClickSelector, 'click', handleMetaClick
+  delegate document, Rails.linkClickSelector, 'click', disableElement
+  delegate document, Rails.linkClickSelector, 'click', handleRemote
+  delegate document, Rails.linkClickSelector, 'click', handleMethod
+
+  delegate document, Rails.buttonClickSelector, 'click', handleDisabledElement
+  delegate document, Rails.buttonClickSelector, 'click', handleConfirm
+  delegate document, Rails.buttonClickSelector, 'click', disableElement
+  delegate document, Rails.buttonClickSelector, 'click', handleRemote
+
+  delegate document, Rails.inputChangeSelector, 'change', handleDisabledElement
+  delegate document, Rails.inputChangeSelector, 'change', handleConfirm
+  delegate document, Rails.inputChangeSelector, 'change', handleRemote
+
+  delegate document, Rails.formSubmitSelector, 'submit', handleDisabledElement
+  delegate document, Rails.formSubmitSelector, 'submit', handleConfirm
+  delegate document, Rails.formSubmitSelector, 'submit', handleRemote
+  # Normal mode submit
+  # Slight timeout so that the submit button gets properly serialized
+  delegate document, Rails.formSubmitSelector, 'submit', (e) -> setTimeout((-> disableElement(e)), 13)
+  delegate document, Rails.formSubmitSelector, 'ajax:send', disableElement
+  delegate document, Rails.formSubmitSelector, 'ajax:complete', enableElement
+
+  delegate document, Rails.formInputClickSelector, 'click', handleDisabledElement
+  delegate document, Rails.formInputClickSelector, 'click', handleConfirm
+  delegate document, Rails.formInputClickSelector, 'click', formSubmitButtonClick
+
+  document.addEventListener('DOMContentLoaded', refreshCSRFTokens)
+  window._rails_loaded = true
+
+if window.Rails is Rails and fire(document, 'rails:attachBindings')
+  Rails.start()
diff --git a/actionview/app/assets/javascripts/rails-ujs/utils/ajax.coffee b/actionview/app/assets/javascripts/rails-ujs/utils/ajax.coffee
new file mode 100644
index 0000000000..cc0e037428
--- /dev/null
+++ b/actionview/app/assets/javascripts/rails-ujs/utils/ajax.coffee
@@ -0,0 +1,95 @@
+#= require ./csrf
+#= require ./event
+
+{ CSRFProtection, fire } = Rails
+
+AcceptHeaders =
+  '*': '*/*'
+  text: 'text/plain'
+  html: 'text/html'
+  xml: 'application/xml, text/xml'
+  json: 'application/json, text/javascript'
+  script: 'text/javascript, application/javascript, application/ecmascript, application/x-ecmascript'
+
+Rails.ajax = (options) ->
+  options = prepareOptions(options)
+  xhr = createXHR options, ->
+    response = processResponse(xhr.response ? xhr.responseText, xhr.getResponseHeader('Content-Type'))
+    if xhr.status // 100 == 2
+      options.success?(response, xhr.statusText, xhr)
+    else
+      options.error?(response, xhr.statusText, xhr)
+    options.complete?(xhr, xhr.statusText)
+
+  if options.beforeSend? && !options.beforeSend(xhr, options)
+    return false
+
+  if xhr.readyState is XMLHttpRequest.OPENED
+    xhr.send(options.data)
+
+prepareOptions = (options) ->
+  options.url = options.url or location.href
+  options.type = options.type.toUpperCase()
+  # append data to url if it's a GET request
+  if options.type is 'GET' and options.data
+    if options.url.indexOf('?') < 0
+      options.url += '?' + options.data
+    else
+      options.url += '&' + options.data
+  # Use "*" as default dataType
+  options.dataType = '*' unless AcceptHeaders[options.dataType]?
+  options.accept = AcceptHeaders[options.dataType]
+  options.accept += ', */*; q=0.01' if options.dataType isnt '*'
+  options
+
+createXHR = (options, done) ->
+  xhr = new XMLHttpRequest()
+  # Open and setup xhr
+  xhr.open(options.type, options.url, true)
+  xhr.setRequestHeader('Accept', options.accept)
+  # Set Content-Type only when sending a string
+  # Sending FormData will automatically set Content-Type to multipart/form-data
+  if typeof options.data is 'string'
+    xhr.setRequestHeader('Content-Type', 'application/x-www-form-urlencoded; charset=UTF-8')
+  xhr.setRequestHeader('X-Requested-With', 'XMLHttpRequest') unless options.crossDomain
+  # Add X-CSRF-Token
+  CSRFProtection(xhr)
+  xhr.withCredentials = !!options.withCredentials
+  xhr.onreadystatechange = ->
+    done(xhr) if xhr.readyState is XMLHttpRequest.DONE
+  xhr
+
+processResponse = (response, type) ->
+  if typeof response is 'string' and typeof type is 'string'
+    if type.match(/\bjson\b/)
+      try response = JSON.parse(response)
+    else if type.match(/\b(?:java|ecma)script\b/)
+      script = document.createElement('script')
+      script.text = response
+      document.head.appendChild(script).parentNode.removeChild(script)
+    else if type.match(/\b(xml|html|svg)\b/)
+      parser = new DOMParser()
+      type = type.replace(/;.+/, '') # remove something like ';charset=utf-8'
+      try response = parser.parseFromString(response, type)
+  response
+
+# Default way to get an element's href. May be overridden at Rails.href.
+Rails.href = (element) -> element.href
+
+# Determines if the request is a cross domain request.
+Rails.isCrossDomain = (url) ->
+  originAnchor = document.createElement('a')
+  originAnchor.href = location.href
+  urlAnchor = document.createElement('a')
+  try
+    urlAnchor.href = url
+    # If URL protocol is false or is a string containing a single colon
+    # *and* host are false, assume it is not a cross-domain request
+    # (should only be the case for IE7 and IE compatibility mode).
+    # Otherwise, evaluate protocol and host of the URL against the origin
+    # protocol and host.
+    !(((!urlAnchor.protocol || urlAnchor.protocol == ':') && !urlAnchor.host) ||
+      (originAnchor.protocol + '//' + originAnchor.host == urlAnchor.protocol + '//' + urlAnchor.host))
+  catch e
+    # If there is an error parsing the URL, assume it is crossDomain.
+    true
diff --git a/actionview/app/assets/javascripts/rails-ujs/utils/csrf.coffee b/actionview/app/assets/javascripts/rails-ujs/utils/csrf.coffee
new file mode 100644
index 0000000000..4eb5ebb414
--- /dev/null
+++ b/actionview/app/assets/javascripts/rails-ujs/utils/csrf.coffee
@@ -0,0 +1,25 @@
+#= require ./dom
+
+{ $ } = Rails
+
+# Up-to-date Cross-Site Request Forgery token
+csrfToken = Rails.csrfToken = ->
+  meta = document.querySelector('meta[name=csrf-token]')
+  meta and meta.content
+
+# URL param that must contain the CSRF token
+csrfParam = Rails.csrfParam = ->
+  meta = document.querySelector('meta[name=csrf-param]')
+  meta and meta.content
+
+# Make sure that every Ajax request sends the CSRF token
+Rails.CSRFProtection = (xhr) ->
+  token = csrfToken()
+  xhr.setRequestHeader('X-CSRF-Token', token) if token?
+
+# Make sure that all forms have actual up-to-date tokens (cached forms contain old ones)
+Rails.refreshCSRFTokens = ->
+  token = csrfToken()
+  param = csrfParam()
+  if token? and param?
+    $('form input[name="' + param + '"]').forEach (input) -> input.value = token
diff --git a/actionview/app/assets/javascripts/rails-ujs/utils/dom.coffee b/actionview/app/assets/javascripts/rails-ujs/utils/dom.coffee
new file mode 100644
index 0000000000..3d3c5bb330
--- /dev/null
+++ b/actionview/app/assets/javascripts/rails-ujs/utils/dom.coffee
@@ -0,0 +1,35 @@
+m = Element.prototype.matches or
+    Element.prototype.matchesSelector or
+    Element.prototype.mozMatchesSelector or
+    Element.prototype.msMatchesSelector or
+    Element.prototype.oMatchesSelector or
+    Element.prototype.webkitMatchesSelector
+
+# Checks if the given native dom element matches the selector
+# element::
+#   native DOM element
+# selector::
+#   css selector string or
+#   a javascript object with `selector` and `exclude` properties
+#   Examples: "form", { selector: "form", exclude: "form[data-remote='true']"}
+Rails.matches = (element, selector) ->
+  if selector.exclude?
+    m.call(element, selector.selector) and not m.call(element, selector.exclude)
+  else
+    m.call(element, selector)
+
+# get and set data on a given element using "expando properties"
+# See: https://developer.mozilla.org/en-US/docs/Glossary/Expando
+expando = '_ujsData'
+
+Rails.getData = (element, key) ->
+  element[expando]?[key]
+
+Rails.setData = (element, key, value) ->
+  element[expando] ?= {}
+  element[expando][key] = value
+
+# a wrapper for document.querySelectorAll
+# returns an Array
+Rails.$ = (selector) ->
+  Array.prototype.slice.call(document.querySelectorAll(selector))
diff --git a/actionview/app/assets/javascripts/rails-ujs/utils/event.coffee b/actionview/app/assets/javascripts/rails-ujs/utils/event.coffee
new file mode 100644
index 0000000000..a7eee52060
--- /dev/null
+++ b/actionview/app/assets/javascripts/rails-ujs/utils/event.coffee
@@ -0,0 +1,68 @@
+#= require ./dom
+
+{ matches } = Rails
+
+# Polyfill for CustomEvent in IE9+
+# https://developer.mozilla.org/en-US/docs/Web/API/CustomEvent/CustomEvent#Polyfill
+CustomEvent = window.CustomEvent
+
+if typeof CustomEvent isnt 'function'
+  CustomEvent = (event, params) ->
+    evt = document.createEvent('CustomEvent')
+    evt.initCustomEvent(event, params.bubbles, params.cancelable, params.detail)
+    evt
+
+  CustomEvent.prototype = window.Event.prototype
+
+  # Fix setting `defaultPrevented` when `preventDefault()` is called
+  # http://stackoverflow.com/questions/23349191/event-preventdefault-is-not-working-in-ie-11-for-custom-events
+  { preventDefault } = CustomEvent.prototype
+  CustomEvent.prototype.preventDefault = ->
+    result = preventDefault.call(this)
+    if @cancelable and not @defaultPrevented
+      Object.defineProperty(this, 'defaultPrevented', get: -> true)
+    result
+
+# Triggers a custom event on an element and returns false if the event result is false
+# obj::
+#   a native DOM element
+# name::
+#   string that corrspends to the event you want to trigger
+#   e.g. 'click', 'submit'
+# data::
+#   data you want to pass when you dispatch an event
+fire = Rails.fire = (obj, name, data) ->
+  event = new CustomEvent(
+    name,
+    bubbles: true,
+    cancelable: true,
+    detail: data,
+  )
+  obj.dispatchEvent(event)
+  !event.defaultPrevented
+
+# Helper function, needed to provide consistent behavior in IE
+Rails.stopEverything = (e) ->
+  fire(e.target, 'ujs:everythingStopped')
+  e.preventDefault()
+  e.stopPropagation()
+  e.stopImmediatePropagation()
+
+# Delegates events
+# to a specified parent `element`, which fires event `handler`
+# for the specified `selector` when an event of `eventType` is triggered
+# element::
+#   parent element that will listen for events e.g. document
+# selector::
+#   css selector; or an object that has `selector` and `exclude` properties (see: Rails.matches)
+# eventType::
+#   string representing the event e.g. 'submit', 'click'
+# handler::
+#   the event handler to be called
+Rails.delegate = (element, selector, eventType, handler) ->
+  element.addEventListener eventType, (e) ->
+    target = e.target
+    target = target.parentNode until not (target instanceof Element) or matches(target, selector)
+    if target instanceof Element and handler.call(target, e) == false
+      e.preventDefault()
+      e.stopPropagation()
diff --git a/actionview/app/assets/javascripts/rails-ujs/utils/form.coffee b/actionview/app/assets/javascripts/rails-ujs/utils/form.coffee
new file mode 100644
index 0000000000..736cab08db
--- /dev/null
+++ b/actionview/app/assets/javascripts/rails-ujs/utils/form.coffee
@@ -0,0 +1,36 @@
+#= require ./dom
+
+{ matches } = Rails
+
+toArray = (e) -> Array.prototype.slice.call(e)
+
+Rails.serializeElement = (element, additionalParam) ->
+  inputs = [element]
+  inputs = toArray(element.elements) if matches(element, 'form')
+  params = []
+
+  inputs.forEach (input) ->
+    return if !input.name || input.disabled
+    if matches(input, 'select')
+      toArray(input.options).forEach (option) ->
+        params.push(name: input.name, value: option.value) if option.selected
+    else if input.checked or ['radio', 'checkbox', 'submit'].indexOf(input.type) == -1
+      params.push(name: input.name, value: input.value)
+
+  params.push(additionalParam) if additionalParam
+
+  params.map (param) ->
+    if param.name?
+      "#{encodeURIComponent(param.name)}=#{encodeURIComponent(param.value)}"
+    else
+      param
+  .join('&')
+
+# Helper function that returns form elements that match the specified CSS selector
+# If form is actually a "form" element this will return associated elements outside the from that have
+# the html form attribute set
+Rails.formElements = (form, selector) ->
+  if matches(form, 'form')
+    toArray(form.elements).filter (el) -> matches(el, selector)
+  else
+    toArray(form.querySelectorAll(selector))
diff --git a/actionview/bin/test b/actionview/bin/test
index 404cabba51..c53377cc97 100755
--- a/actionview/bin/test
+++ b/actionview/bin/test
@@ -1,4 +1,5 @@
 #!/usr/bin/env ruby
-COMPONENT_ROOT = File.expand_path("../../", __FILE__)
-require File.expand_path("../tools/test", COMPONENT_ROOT)
-exit Minitest.run(ARGV)
+# frozen_string_literal: true
+
+COMPONENT_ROOT = File.expand_path("..", __dir__)
+require_relative "../../tools/test"
diff --git a/actionview/blade.yml b/actionview/blade.yml
new file mode 100644
index 0000000000..9e5eb953a4
--- /dev/null
+++ b/actionview/blade.yml
@@ -0,0 +1,11 @@
+load_paths:
+  - app/assets/javascripts
+
+logical_paths:
+  - rails-ujs.js
+
+build:
+  logical_paths:
+    - rails-ujs.js
+  path: lib/assets/compiled
+  clean: true
diff --git a/actionview/coffeelint.json b/actionview/coffeelint.json
new file mode 100644
index 0000000000..cf8bf2171b
--- /dev/null
+++ b/actionview/coffeelint.json
@@ -0,0 +1,135 @@
+{
+  "arrow_spacing": {
+    "level": "warn"
+  },
+  "braces_spacing": {
+    "level": "warn",
+    "spaces": 1,
+    "empty_object_spaces": 0
+  },
+  "camel_case_classes": {
+    "level": "error"
+  },
+  "coffeescript_error": {
+    "level": "error"
+  },
+  "colon_assignment_spacing": {
+    "level": "warn",
+    "spacing": {
+      "left": 0,
+      "right": 1
+    }
+  },
+  "cyclomatic_complexity": {
+    "level": "warn",
+    "value": 10
+  },
+  "duplicate_key": {
+    "level": "error"
+  },
+  "empty_constructor_needs_parens": {
+    "level": "warn"
+  },
+  "ensure_comprehensions": {
+    "level": "warn"
+  },
+  "eol_last": {
+    "level": "warn"
+  },
+  "indentation": {
+    "value": 2,
+    "level": "error"
+  },
+  "line_endings": {
+    "level": "warn",
+    "value": "unix"
+  },
+  "max_line_length": {
+    "value": 80,
+    "level": "ignore",
+    "limitComments": true
+  },
+  "missing_fat_arrows": {
+    "level": "ignore"
+  },
+  "newlines_after_classes": {
+    "value": 3,
+    "level": "warn"
+  },
+  "no_backticks": {
+    "level": "error"
+  },
+  "no_debugger": {
+    "level": "warn",
+    "console": false
+  },
+  "no_empty_functions": {
+    "level": "warn"
+  },
+  "no_empty_param_list": {
+    "level": "warn"
+  },
+  "no_implicit_braces": {
+    "level": "ignore",
+    "strict": true
+  },
+  "no_implicit_parens": {
+    "level": "ignore",
+    "strict": true
+  },
+  "no_interpolation_in_single_quotes": {
+    "level": "warn"
+  },
+  "no_nested_string_interpolation": {
+    "level": "warn"
+  },
+  "no_plusplus": {
+    "level": "warn"
+  },
+  "no_private_function_fat_arrows": {
+    "level": "warn"
+  },
+  "no_stand_alone_at": {
+    "level": "warn"
+  },
+  "no_tabs": {
+    "level": "error"
+  },
+  "no_this": {
+    "level": "warn"
+  },
+  "no_throwing_strings": {
+    "level": "error"
+  },
+  "no_trailing_semicolons": {
+    "level": "error"
+  },
+  "no_trailing_whitespace": {
+    "level": "error",
+    "allowed_in_comments": false,
+    "allowed_in_empty_lines": true
+  },
+  "no_unnecessary_double_quotes": {
+    "level": "warn"
+  },
+  "no_unnecessary_fat_arrows": {
+    "level": "warn"
+  },
+  "non_empty_constructor_needs_parens": {
+    "level": "warn"
+  },
+  "prefer_english_operator": {
+    "level": "ignore",
+    "doubleNotLevel": "warn"
+  },
+  "space_operators": {
+    "level": "warn"
+  },
+  "spacing_after_comma": {
+    "level": "warn"
+  },
+  "transform_messes_up_line_numbers": {
+    "level": "warn"
+  }
+}
+
diff --git a/actionview/lib/action_view.rb b/actionview/lib/action_view.rb
index 0a87500a52..c1eeda75f5 100644
--- a/actionview/lib/action_view.rb
+++ b/actionview/lib/action_view.rb
@@ -1,5 +1,7 @@
+# frozen_string_literal: true
+
 #--
-# Copyright (c) 2004-2016 David Heinemeier Hansson
+# Copyright (c) 2004-2018 David Heinemeier Hansson
 #
 # Permission is hereby granted, free of charge, to any person obtaining
 # a copy of this software and associated documentation files (the
@@ -21,9 +23,9 @@
 # WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 #++
 
-require 'active_support'
-require 'active_support/rails'
-require 'action_view/version'
+require "active_support"
+require "active_support/rails"
+require "action_view/version"
 
 module ActionView
   extend ActiveSupport::Autoload
@@ -74,7 +76,6 @@ module ActionView
       autoload :MissingTemplate
       autoload :ActionViewError
       autoload :EncodingError
-      autoload :MissingRequestError
       autoload :TemplateError
       autoload :WrongEncodingError
     end
@@ -89,8 +90,8 @@ module ActionView
   end
 end
 
-require 'active_support/core_ext/string/output_safety'
+require "active_support/core_ext/string/output_safety"
 
 ActiveSupport.on_load(:i18n) do
-  I18n.load_path << "#{File.dirname(__FILE__)}/action_view/locale/en.yml"
+  I18n.load_path << File.expand_path("action_view/locale/en.yml", __dir__)
 end
diff --git a/actionview/lib/action_view/base.rb b/actionview/lib/action_view/base.rb
index ad1cb1a4be..d41fe2a608 100644
--- a/actionview/lib/action_view/base.rb
+++ b/actionview/lib/action_view/base.rb
@@ -1,23 +1,25 @@
-require 'active_support/core_ext/module/attr_internal'
-require 'active_support/core_ext/module/attribute_accessors'
-require 'active_support/ordered_options'
-require 'action_view/log_subscriber'
-require 'action_view/helpers'
-require 'action_view/context'
-require 'action_view/template'
-require 'action_view/lookup_context'
+# frozen_string_literal: true
+
+require "active_support/core_ext/module/attr_internal"
+require "active_support/core_ext/module/attribute_accessors"
+require "active_support/ordered_options"
+require "action_view/log_subscriber"
+require "action_view/helpers"
+require "action_view/context"
+require "action_view/template"
+require "action_view/lookup_context"
 
 module ActionView #:nodoc:
   # = Action View Base
   #
   # Action View templates can be written in several ways.
-  # If the template file has a <tt>.erb</tt> extension, then it uses the erubis[https://rubygems.org/gems/erubis]
+  # If the template file has a <tt>.erb</tt> extension, then it uses the erubi[https://rubygems.org/gems/erubi]
   # template system which can embed Ruby into an HTML document.
   # If the template file has a <tt>.builder</tt> extension, then Jim Weirich's Builder::XmlMarkup library is used.
   #
   # == ERB
   #
-  # You trigger ERB by using embeddings such as <% %>, <% -%>, and <%= %>. The <%= %> tag set is used when you want output. Consider the
+  # You trigger ERB by using embeddings such as <tt><% %></tt>, <tt><% -%></tt>, and <tt><%= %></tt>. The <tt><%= %></tt> tag set is used when you want output. Consider the
   # following loop for names:
   #
   #   <b>Names of all the people</b>
@@ -25,7 +27,7 @@ module ActionView #:nodoc:
   #     Name: <%= person.name %><br/>
   #   <% end %>
   #
-  # The loop is setup in regular embedding tags <% %> and the name is written using the output embedding tag <%= %>. Note that this
+  # The loop is setup in regular embedding tags <tt><% %></tt>, and the name is written using the output embedding tag <tt><%= %></tt>. Note that this
   # is not just a usage suggestion. Regular output functions like print or puts won't work with ERB templates. So this would be wrong:
   #
   #   <%# WRONG %>
@@ -33,9 +35,9 @@ module ActionView #:nodoc:
   #
   # If you absolutely must write from within a function use +concat+.
   #
-  # When on a line that only contains whitespaces except for the tag, <% %> suppress leading and trailing whitespace,
-  # including the trailing newline. <% %> and <%- -%> are the same.
-  # Note however that <%= %> and <%= -%> are different: only the latter removes trailing whitespaces.
+  # When on a line that only contains whitespaces except for the tag, <tt><% %></tt> suppresses leading and trailing whitespace,
+  # including the trailing newline. <tt><% %></tt> and <tt><%- -%></tt> are the same.
+  # Note however that <tt><%= %></tt> and <tt><%= -%></tt> are different: only the latter removes trailing whitespaces.
   #
   # === Using sub templates
   #
@@ -110,7 +112,7 @@ module ActionView #:nodoc:
   #     <p>A product of Danish Design during the Winter of '79...</p>
   #   </div>
   #
-  # A full-length RSS example actually used on Basecamp:
+  # Here is a full-length RSS example actually used on Basecamp:
   #
   #   xml.rss("version" => "2.0", "xmlns:dc" => "http://purl.org/dc/elements/1.1/") do
   #     xml.channel do
@@ -140,36 +142,31 @@ module ActionView #:nodoc:
     include Helpers, ::ERB::Util, Context
 
     # Specify the proc used to decorate input tags that refer to attributes with errors.
-    cattr_accessor :field_error_proc
-    @@field_error_proc = Proc.new{ |html_tag, instance| "<div class=\"field_with_errors\">#{html_tag}</div>".html_safe }
+    cattr_accessor :field_error_proc, default: Proc.new { |html_tag, instance| "<div class=\"field_with_errors\">#{html_tag}</div>".html_safe }
 
     # How to complete the streaming when an exception occurs.
     # This is our best guess: first try to close the attribute, then the tag.
-    cattr_accessor :streaming_completion_on_exception
-    @@streaming_completion_on_exception = %("><script>window.location = "/500.html"</script></html>)
+    cattr_accessor :streaming_completion_on_exception, default: %("><script>window.location = "/500.html"</script></html>)
 
     # Specify whether rendering within namespaced controllers should prefix
     # the partial paths for ActiveModel objects with the namespace.
     # (e.g., an Admin::PostsController would render @post using /admin/posts/_post.erb)
-    cattr_accessor :prefix_partial_path_with_controller_namespace
-    @@prefix_partial_path_with_controller_namespace = true
+    cattr_accessor :prefix_partial_path_with_controller_namespace, default: true
 
     # Specify default_formats that can be rendered.
     cattr_accessor :default_formats
 
     # Specify whether an error should be raised for missing translations
-    cattr_accessor :raise_on_missing_translations
-    @@raise_on_missing_translations = false
+    cattr_accessor :raise_on_missing_translations, default: false
 
     # Specify whether submit_tag should automatically disable on click
-    cattr_accessor :automatically_disable_submit_tag
-    @@automatically_disable_submit_tag = true
+    cattr_accessor :automatically_disable_submit_tag, default: true
 
     class_attribute :_routes
     class_attribute :logger
 
     class << self
-      delegate :erb_trim_mode=, :to => 'ActionView::Template::Handlers::ERB'
+      delegate :erb_trim_mode=, to: "ActionView::Template::Handlers::ERB"
 
       def cache_template_loading
         ActionView::Resolver.caching?
@@ -187,8 +184,8 @@ module ActionView #:nodoc:
     attr_accessor :view_renderer
     attr_internal :config, :assigns
 
-    delegate :lookup_context, :to => :view_renderer
-    delegate :formats, :formats=, :locale, :locale=, :view_paths, :view_paths=, :to => :lookup_context
+    delegate :lookup_context, to: :view_renderer
+    delegate :formats, :formats=, :locale, :locale=, :view_paths, :view_paths=, to: :lookup_context
 
     def assign(new_assigns) # :nodoc:
       @_assigns = new_assigns.each { |key, value| instance_variable_set("@#{key}", value) }
@@ -207,6 +204,7 @@ module ActionView #:nodoc:
         @view_renderer = ActionView::Renderer.new(lookup_context)
       end
 
+      @cache_hit = {}
       assign(assigns)
       assign_controller(controller)
       _prepare_context
diff --git a/actionview/lib/action_view/buffers.rb b/actionview/lib/action_view/buffers.rb
index be5d86b1dc..2a378fdc3c 100644
--- a/actionview/lib/action_view/buffers.rb
+++ b/actionview/lib/action_view/buffers.rb
@@ -1,4 +1,6 @@
-require 'active_support/core_ext/string/output_safety'
+# frozen_string_literal: true
+
+require "active_support/core_ext/string/output_safety"
 
 module ActionView
   class OutputBuffer < ActiveSupport::SafeBuffer #:nodoc:
diff --git a/actionview/lib/action_view/context.rb b/actionview/lib/action_view/context.rb
index ee263df484..665a9e3171 100644
--- a/actionview/lib/action_view/context.rb
+++ b/actionview/lib/action_view/context.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActionView
   module CompiledTemplates #:nodoc:
     # holds compiled template code
@@ -17,7 +19,6 @@ module ActionView
     attr_accessor :output_buffer, :view_flow
 
     # Prepares the context by setting the appropriate instance variables.
-    # :api: plugin
     def _prepare_context
       @view_flow     = OutputFlow.new
       @output_buffer = nil
@@ -27,8 +28,7 @@ module ActionView
     # Encapsulates the interaction with the view flow so it
     # returns the correct buffer on +yield+. This is usually
     # overwritten by helpers to add more behavior.
-    # :api: plugin
-    def _layout_for(name=nil)
+    def _layout_for(name = nil)
       name ||= :layout
       view_flow.get(name).html_safe
     end
diff --git a/actionview/lib/action_view/dependency_tracker.rb b/actionview/lib/action_view/dependency_tracker.rb
index 7731773040..182f6e2eef 100644
--- a/actionview/lib/action_view/dependency_tracker.rb
+++ b/actionview/lib/action_view/dependency_tracker.rb
@@ -1,5 +1,7 @@
-require 'concurrent/map'
-require 'action_view/path_set'
+# frozen_string_literal: true
+
+require "concurrent/map"
+require "action_view/path_set"
 
 module ActionView
   class DependencyTracker # :nodoc:
@@ -105,7 +107,6 @@ module ActionView
       attr_reader :name, :template
       private :name, :template
 
-
       private
         def source
           template.source
@@ -142,7 +143,7 @@ module ActionView
 
         def add_static_dependency(dependencies, dependency)
           if dependency
-            if dependency.include?('/')
+            if dependency.include?("/")
               dependencies << dependency
             else
               dependencies << "#{directory}/#{dependency}"
@@ -163,7 +164,7 @@ module ActionView
         def explicit_dependencies
           dependencies = source.scan(EXPLICIT_DEPENDENCY).flatten.uniq
 
-          wildcards, explicits = dependencies.partition { |dependency| dependency[-1] == '*' }
+          wildcards, explicits = dependencies.partition { |dependency| dependency[-1] == "*" }
 
           (explicits + resolve_directories(wildcards)).uniq
         end
diff --git a/actionview/lib/action_view/digestor.rb b/actionview/lib/action_view/digestor.rb
index f3c29d663c..1cf0bd3016 100644
--- a/actionview/lib/action_view/digestor.rb
+++ b/actionview/lib/action_view/digestor.rb
@@ -1,21 +1,28 @@
-require 'concurrent/map'
-require 'action_view/dependency_tracker'
-require 'monitor'
+# frozen_string_literal: true
+
+require "concurrent/map"
+require "action_view/dependency_tracker"
+require "monitor"
 
 module ActionView
   class Digestor
     @@digest_mutex = Mutex.new
 
+    module PerExecutionDigestCacheExpiry
+      def self.before(target)
+        ActionView::LookupContext::DetailsKey.clear
+      end
+    end
+
     class << self
       # Supported options:
       #
       # * <tt>name</tt>   - Template name
       # * <tt>finder</tt>  - An instance of <tt>ActionView::LookupContext</tt>
       # * <tt>dependencies</tt>  - An array of dependent views
-      # * <tt>partial</tt>  - Specifies whether the template is a partial
       def digest(name:, finder:, dependencies: [])
         dependencies ||= []
-        cache_key = [ name, finder.rendered_format, dependencies ].flatten.compact.join('.')
+        cache_key = [ name, finder.rendered_format, dependencies ].flatten.compact.join(".")
 
         # this is a correctly done double-checked locking idiom
         # (Concurrent::Map's lookups have volatile semantics)
@@ -42,8 +49,7 @@ module ActionView
         options = {}
         options[:formats] = [finder.rendered_format] if finder.rendered_format
 
-        if finder.disable_cache { finder.exists?(logical_name, [], partial, [], options) }
-          template = finder.disable_cache { finder.find(logical_name, [], partial, [], options) }
+        if template = finder.disable_cache { finder.find_all(logical_name, [], partial, [], options).first }
           finder.rendered_format ||= template.formats.first
 
           if node = seen[template.identifier] # handle cycles in the tree
@@ -58,8 +64,10 @@ module ActionView
             node
           end
         else
-          logger.error "  '#{name}' file doesn't exist, so no dependencies"
-          logger.error "  Couldn't find template for digesting: #{name}"
+          unless name.include?("#") # Dynamic template partial names can never be tracked
+            logger.error "  Couldn't find template for digesting: #{name}"
+          end
+
           seen[name] ||= Missing.new(name, logical_name, nil)
         end
       end
@@ -81,7 +89,7 @@ module ActionView
       end
 
       def digest(finder, stack = [])
-        Digest::MD5.hexdigest("#{template.source}-#{dependency_digest(finder, stack)}")
+        ActiveSupport::Digest.hexdigest("#{template.source}-#{dependency_digest(finder, stack)}")
       end
 
       def dependency_digest(finder, stack)
@@ -105,7 +113,7 @@ module ActionView
     class Partial < Node; end
 
     class Missing < Node
-      def digest(finder, _ = []) '' end
+      def digest(finder, _ = []) "" end
     end
 
     class Injected < Node
diff --git a/actionview/lib/action_view/flows.rb b/actionview/lib/action_view/flows.rb
index 4b912f0b2b..ff44fa6619 100644
--- a/actionview/lib/action_view/flows.rb
+++ b/actionview/lib/action_view/flows.rb
@@ -1,11 +1,13 @@
-require 'active_support/core_ext/string/output_safety'
+# frozen_string_literal: true
+
+require "active_support/core_ext/string/output_safety"
 
 module ActionView
   class OutputFlow #:nodoc:
     attr_reader :content
 
     def initialize
-      @content = Hash.new { |h,k| h[k] = ActiveSupport::SafeBuffer.new }
+      @content = Hash.new { |h, k| h[k] = ActiveSupport::SafeBuffer.new }
     end
 
     # Called by _layout_for to read stored values.
@@ -23,7 +25,6 @@ module ActionView
       @content[key] << value
     end
     alias_method :append!, :append
-
   end
 
   class StreamingFlow < OutputFlow #:nodoc:
@@ -68,8 +69,8 @@ module ActionView
 
     private
 
-    def inside_fiber?
-      Fiber.current.object_id != @root
-    end
+      def inside_fiber?
+        Fiber.current.object_id != @root
+      end
   end
 end
diff --git a/actionview/lib/action_view/gem_version.rb b/actionview/lib/action_view/gem_version.rb
index 5fc4f3f1b9..ff7f2bb853 100644
--- a/actionview/lib/action_view/gem_version.rb
+++ b/actionview/lib/action_view/gem_version.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActionView
   # Returns the version of the currently loaded Action View as a <tt>Gem::Version</tt>
   def self.gem_version
@@ -6,9 +8,9 @@ module ActionView
 
   module VERSION
     MAJOR = 5
-    MINOR = 1
+    MINOR = 2
     TINY  = 0
-    PRE   = "alpha"
+    PRE   = "beta2"
 
     STRING = [MAJOR, MINOR, TINY, PRE].compact.join(".")
   end
diff --git a/actionview/lib/action_view/helpers.rb b/actionview/lib/action_view/helpers.rb
index 787e9d67b2..46f20c4277 100644
--- a/actionview/lib/action_view/helpers.rb
+++ b/actionview/lib/action_view/helpers.rb
@@ -1,4 +1,6 @@
-require 'active_support/benchmarkable'
+# frozen_string_literal: true
+
+require "active_support/benchmarkable"
 
 module ActionView #:nodoc:
   module Helpers #:nodoc:
diff --git a/actionview/lib/action_view/helpers/active_model_helper.rb b/actionview/lib/action_view/helpers/active_model_helper.rb
index d5222e3616..e41a95d2ce 100644
--- a/actionview/lib/action_view/helpers/active_model_helper.rb
+++ b/actionview/lib/action_view/helpers/active_model_helper.rb
@@ -1,9 +1,11 @@
-require 'active_support/core_ext/module/attribute_accessors'
-require 'active_support/core_ext/enumerable'
+# frozen_string_literal: true
+
+require "active_support/core_ext/module/attribute_accessors"
+require "active_support/core_ext/enumerable"
 
 module ActionView
   # = Active Model Helpers
-  module Helpers
+  module Helpers #:nodoc:
     module ActiveModelHelper
     end
 
@@ -15,8 +17,8 @@ module ActionView
         end
       end
 
-      def content_tag(*)
-        error_wrapping(super)
+      def content_tag(type, options, *)
+        select_markup_helper?(type) ? super : error_wrapping(super)
       end
 
       def tag(type, options, *)
@@ -37,13 +39,17 @@ module ActionView
 
       private
 
-      def object_has_errors?
-        object.respond_to?(:errors) && object.errors.respond_to?(:[]) && error_message.present?
-      end
+        def object_has_errors?
+          object.respond_to?(:errors) && object.errors.respond_to?(:[]) && error_message.present?
+        end
 
-      def tag_generate_errors?(options)
-        options['type'] != 'hidden'
-      end
+        def select_markup_helper?(type)
+          ["optgroup", "option"].include?(type)
+        end
+
+        def tag_generate_errors?(options)
+          options["type"] != "hidden"
+        end
     end
   end
 end
diff --git a/actionview/lib/action_view/helpers/asset_tag_helper.rb b/actionview/lib/action_view/helpers/asset_tag_helper.rb
index 413c35954c..da630129cb 100644
--- a/actionview/lib/action_view/helpers/asset_tag_helper.rb
+++ b/actionview/lib/action_view/helpers/asset_tag_helper.rb
@@ -1,7 +1,11 @@
-require 'active_support/core_ext/array/extract_options'
-require 'active_support/core_ext/hash/keys'
-require 'action_view/helpers/asset_url_helper'
-require 'action_view/helpers/tag_helper'
+# frozen_string_literal: true
+
+require "active_support/core_ext/array/extract_options"
+require "active_support/core_ext/hash/keys"
+require "active_support/core_ext/object/inclusion"
+require "active_support/core_ext/object/try"
+require "action_view/helpers/asset_url_helper"
+require "action_view/helpers/tag_helper"
 
 module ActionView
   # = Action View Asset Tag Helpers
@@ -11,7 +15,7 @@ module ActionView
     # the assets exist before linking to them:
     #
     #   image_tag("rails.png")
-    #   # => <img alt="Rails" src="/assets/rails.png" />
+    #   # => <img src="/assets/rails.png" />
     #   stylesheet_link_tag("application")
     #   # => <link href="/assets/application.css?body=1" media="screen" rel="stylesheet" />
     module AssetTagHelper
@@ -35,18 +39,40 @@ module ActionView
       # When the Asset Pipeline is enabled, you can pass the name of your manifest as
       # source, and include other JavaScript or CoffeeScript files inside the manifest.
       #
+      # If the server supports Early Hints header links for these assets will be
+      # automatically pushed.
+      #
+      # ==== Options
+      #
+      # When the last parameter is a hash you can add HTML attributes using that
+      # parameter. The following options are supported:
+      #
+      # * <tt>:extname</tt>  - Append an extension to the generated url unless the extension
+      #   already exists. This only applies for relative urls.
+      # * <tt>:protocol</tt>  - Sets the protocol of the generated url, this option only
+      #   applies when a relative url and +host+ options are provided.
+      # * <tt>:host</tt>  - When a relative url is provided the host is added to the
+      #   that path.
+      # * <tt>:skip_pipeline</tt>  - This option is used to bypass the asset pipeline
+      #   when it is set to true.
+      #
+      # ==== Examples
+      #
       #   javascript_include_tag "xmlhr"
-      #   # => <script src="/assets/xmlhr.js?1284139606"></script>
+      #   # => <script src="/assets/xmlhr.debug-1284139606.js"></script>
+      #
+      #   javascript_include_tag "xmlhr", host: "localhost", protocol: "https"
+      #   # => <script src="https://localhost/assets/xmlhr.debug-1284139606.js"></script>
       #
       #   javascript_include_tag "template.jst", extname: false
-      #   # => <script src="/assets/template.jst?1284139606"></script>
+      #   # => <script src="/assets/template.debug-1284139606.jst"></script>
       #
       #   javascript_include_tag "xmlhr.js"
-      #   # => <script src="/assets/xmlhr.js?1284139606"></script>
+      #   # => <script src="/assets/xmlhr.debug-1284139606.js"></script>
       #
       #   javascript_include_tag "common.javascript", "/elsewhere/cools"
-      #   # => <script src="/assets/common.javascript?1284139606"></script>
-      #   #    <script src="/elsewhere/cools.js?1423139606"></script>
+      #   # => <script src="/assets/common.javascript.debug-1284139606.js"></script>
+      #   #    <script src="/elsewhere/cools.debug-1284139606.js"></script>
       #
       #   javascript_include_tag "http://www.example.com/xmlhr"
       #   # => <script src="http://www.example.com/xmlhr"></script>
@@ -55,13 +81,21 @@ module ActionView
       #   # => <script src="http://www.example.com/xmlhr.js"></script>
       def javascript_include_tag(*sources)
         options = sources.extract_options!.stringify_keys
-        path_options = options.extract!('protocol', 'extname', 'host').symbolize_keys
-        sources.uniq.map { |source|
+        path_options = options.extract!("protocol", "extname", "host", "skip_pipeline").symbolize_keys
+        early_hints_links = []
+
+        sources_tags = sources.uniq.map { |source|
+          href = path_to_javascript(source, path_options)
+          early_hints_links << "<#{href}>; rel=preload; as=script"
           tag_options = {
-            "src" => path_to_javascript(source, path_options)
+            "src" => href
           }.merge!(options)
           content_tag("script".freeze, "", tag_options)
         }.join("\n").html_safe
+
+        request.send_early_hints("Link" => early_hints_links.join("\n")) if respond_to?(:request) && request
+
+        sources_tags
       end
 
       # Returns a stylesheet link tag for the sources specified as arguments. If
@@ -71,6 +105,9 @@ module ActionView
       # to "screen", so you must explicitly set it to "all" for the stylesheet(s) to
       # apply to all media types.
       #
+      # If the server supports Early Hints header links for these assets  will be
+      # automatically pushed.
+      #
       #   stylesheet_link_tag "style"
       #   # => <link href="/assets/style.css" media="screen" rel="stylesheet" />
       #
@@ -91,22 +128,29 @@ module ActionView
       #   #    <link href="/css/stylish.css" media="screen" rel="stylesheet" />
       def stylesheet_link_tag(*sources)
         options = sources.extract_options!.stringify_keys
-        path_options = options.extract!('protocol', 'host').symbolize_keys
+        path_options = options.extract!("protocol", "host", "skip_pipeline").symbolize_keys
+        early_hints_links = []
 
-        sources.uniq.map { |source|
+        sources_tags = sources.uniq.map { |source|
+          href = path_to_stylesheet(source, path_options)
+          early_hints_links << "<#{href}>; rel=preload; as=stylesheet"
           tag_options = {
             "rel" => "stylesheet",
             "media" => "screen",
-            "href" => path_to_stylesheet(source, path_options)
+            "href" => href
           }.merge!(options)
           tag(:link, tag_options)
         }.join("\n").html_safe
+
+        request.send_early_hints("Link" => early_hints_links.join("\n")) if respond_to?(:request) && request
+
+        sources_tags
       end
 
       # Returns a link tag that browsers and feed readers can use to auto-detect
-      # an RSS or Atom feed. The +type+ can either be <tt>:rss</tt> (default) or
-      # <tt>:atom</tt>. Control the link options in url_for format using the
-      # +url_options+. You can modify the LINK tag itself in +tag_options+.
+      # an RSS, Atom, or JSON feed. The +type+ can be <tt>:rss</tt> (default),
+      # <tt>:atom</tt>, or <tt>:json</tt>. Control the link options in url_for format
+      # using the +url_options+. You can modify the LINK tag itself in +tag_options+.
       #
       # ==== Options
       #
@@ -120,6 +164,8 @@ module ActionView
       #   # => <link rel="alternate" type="application/rss+xml" title="RSS" href="http://www.currenthost.com/controller/action" />
       #   auto_discovery_link_tag(:atom)
       #   # => <link rel="alternate" type="application/atom+xml" title="ATOM" href="http://www.currenthost.com/controller/action" />
+      #   auto_discovery_link_tag(:json)
+      #   # => <link rel="alternate" type="application/json" title="JSON" href="http://www.currenthost.com/controller/action" />
       #   auto_discovery_link_tag(:rss, {action: "feed"})
       #   # => <link rel="alternate" type="application/rss+xml" title="RSS" href="http://www.currenthost.com/controller/feed" />
       #   auto_discovery_link_tag(:rss, {action: "feed"}, {title: "My RSS"})
@@ -129,8 +175,8 @@ module ActionView
       #   auto_discovery_link_tag(:rss, "http://www.example.com/feed.rss", {title: "Example RSS"})
       #   # => <link rel="alternate" type="application/rss+xml" title="Example RSS" href="http://www.example.com/feed.rss" />
       def auto_discovery_link_tag(type = :rss, url_options = {}, tag_options = {})
-        if !(type == :rss || type == :atom) && tag_options[:type].blank?
-          raise ArgumentError.new("You should pass :type tag_option key explicitly, because you have passed #{type} type other than :rss or :atom.")
+        if !(type == :rss || type == :atom || type == :json) && tag_options[:type].blank?
+          raise ArgumentError.new("You should pass :type tag_option key explicitly, because you have passed #{type} type other than :rss, :atom, or :json.")
         end
 
         tag(
@@ -138,7 +184,7 @@ module ActionView
           "rel"   => tag_options[:rel] || "alternate",
           "type"  => tag_options[:type] || Template::Types[type].to_s,
           "title" => tag_options[:title] || type.to_s.upcase,
-          "href"  => url_options.is_a?(Hash) ? url_for(url_options.merge(:only_path => false)) : url_options
+          "href"  => url_options.is_a?(Hash) ? url_for(url_options.merge(only_path: false)) : url_options
         )
       end
 
@@ -169,52 +215,132 @@ module ActionView
       #
       #   favicon_link_tag 'mb-icon.png', rel: 'apple-touch-icon', type: 'image/png'
       #   # => <link href="/assets/mb-icon.png" rel="apple-touch-icon" type="image/png" />
-      def favicon_link_tag(source='favicon.ico', options={})
-        tag('link', {
-          :rel  => 'shortcut icon',
-          :type => 'image/x-icon',
-          :href => path_to_image(source)
+      def favicon_link_tag(source = "favicon.ico", options = {})
+        tag("link", {
+          rel: "shortcut icon",
+          type: "image/x-icon",
+          href: path_to_image(source, skip_pipeline: options.delete(:skip_pipeline))
         }.merge!(options.symbolize_keys))
       end
 
+      # Returns a link tag that browsers can use to preload the +source+.
+      # The +source+ can be the path of an resource managed by asset pipeline,
+      # a full path or an URI.
+      #
+      # ==== Options
+      #
+      # * <tt>:type</tt>  - Override the auto-generated mime type, defaults to the mime type for +source+ extension.
+      # * <tt>:as</tt>  - Override the auto-generated value for as attribute, calculated using +source+ extension and mime type.
+      # * <tt>:crossorigin</tt>  - Specify the crossorigin attribute, required to load cross-origin resources.
+      # * <tt>:nopush</tt>  - Specify if the use of server push is not desired for the resource. Defaults to +false+.
+      #
+      # ==== Examples
+      #
+      #   preload_link_tag("custom_theme.css")
+      #   # => <link rel="preload" href="/assets/custom_theme.css" as="style" type="text/css" />
+      #
+      #   preload_link_tag("/videos/video.webm")
+      #   # => <link rel="preload" href="/videos/video.mp4" as="video" type="video/webm" />
+      #
+      #   preload_link_tag(post_path(format: :json), as: "fetch")
+      #   # => <link rel="preload" href="/posts.json" as="fetch" type="application/json" />
+      #
+      #   preload_link_tag("worker.js", as: "worker")
+      #   # => <link rel="preload" href="/assets/worker.js" as="worker" type="text/javascript" />
+      #
+      #   preload_link_tag("//example.com/font.woff2")
+      #   # => <link rel="preload" href="//example.com/font.woff2" as="font" type="font/woff2" crossorigin="anonymous"/>
+      #
+      #   preload_link_tag("//example.com/font.woff2", crossorigin: "use-credentials")
+      #   # => <link rel="preload" href="//example.com/font.woff2" as="font" type="font/woff2" crossorigin="use-credentials" />
+      #
+      #   preload_link_tag("/media/audio.ogg", nopush: true)
+      #   # => <link rel="preload" href="/media/audio.ogg" as="audio" type="audio/ogg" />
+      #
+      def preload_link_tag(source, options = {})
+        href = asset_path(source, skip_pipeline: options.delete(:skip_pipeline))
+        extname = File.extname(source).downcase.delete(".")
+        mime_type = options.delete(:type) || Template::Types[extname].try(:to_s)
+        as_type = options.delete(:as) || resolve_link_as(extname, mime_type)
+        crossorigin = options.delete(:crossorigin)
+        crossorigin = "anonymous" if crossorigin == true || (crossorigin.blank? && as_type == "font")
+        nopush = options.delete(:nopush) || false
+
+        link_tag = tag.link({
+          rel: "preload",
+          href: href,
+          as: as_type,
+          type: mime_type,
+          crossorigin: crossorigin
+        }.merge!(options.symbolize_keys))
+
+        early_hints_link = "<#{href}>; rel=preload; as=#{as_type}"
+        early_hints_link += "; type=#{mime_type}" if mime_type
+        early_hints_link += "; crossorigin=#{crossorigin}" if crossorigin
+        early_hints_link += "; nopush" if nopush
+
+        request.send_early_hints("Link" => early_hints_link) if respond_to?(:request) && request
+
+        link_tag
+      end
+
       # Returns an HTML image tag for the +source+. The +source+ can be a full
-      # path or a file.
+      # path, a file or an Active Storage attachment.
       #
       # ==== Options
       #
       # You can add HTML attributes using the +options+. The +options+ supports
-      # two additional keys for convenience and conformance:
+      # additional keys for convenience and conformance:
       #
-      # * <tt>:alt</tt>  - If no alt text is given, the file name part of the
-      #   +source+ is used (capitalized and without the extension)
       # * <tt>:size</tt> - Supplied as "{Width}x{Height}" or "{Number}", so "30x45" becomes
       #   width="30" and height="45", and "50" becomes width="50" and height="50".
       #   <tt>:size</tt> will be ignored if the value is not in the correct format.
+      # * <tt>:srcset</tt> - If supplied as a hash or array of <tt>[source, descriptor]</tt>
+      #   pairs, each image path will be expanded before the list is formatted as a string.
       #
       # ==== Examples
       #
+      # Assets (images that are part of your app):
+      #
       #   image_tag("icon")
-      #   # => <img alt="Icon" src="/assets/icon" />
+      #   # => <img src="/assets/icon" />
       #   image_tag("icon.png")
-      #   # => <img alt="Icon" src="/assets/icon.png" />
+      #   # => <img src="/assets/icon.png" />
       #   image_tag("icon.png", size: "16x10", alt: "Edit Entry")
       #   # => <img src="/assets/icon.png" width="16" height="10" alt="Edit Entry" />
       #   image_tag("/icons/icon.gif", size: "16")
-      #   # => <img src="/icons/icon.gif" width="16" height="16" alt="Icon" />
+      #   # => <img src="/icons/icon.gif" width="16" height="16" />
       #   image_tag("/icons/icon.gif", height: '32', width: '32')
-      #   # => <img alt="Icon" height="32" src="/icons/icon.gif" width="32" />
+      #   # => <img height="32" src="/icons/icon.gif" width="32" />
       #   image_tag("/icons/icon.gif", class: "menu_icon")
-      #   # => <img alt="Icon" class="menu_icon" src="/icons/icon.gif" />
+      #   # => <img class="menu_icon" src="/icons/icon.gif" />
       #   image_tag("/icons/icon.gif", data: { title: 'Rails Application' })
       #   # => <img data-title="Rails Application" src="/icons/icon.gif" />
-      def image_tag(source, options={})
+      #   image_tag("icon.png", srcset: { "icon_2x.png" => "2x", "icon_4x.png" => "4x" })
+      #   # => <img src="/assets/icon.png" srcset="/assets/icon_2x.png 2x, /assets/icon_4x.png 4x">
+      #   image_tag("pic.jpg", srcset: [["pic_1024.jpg", "1024w"], ["pic_1980.jpg", "1980w"]], sizes: "100vw")
+      #   # => <img src="/assets/pic.jpg" srcset="/assets/pic_1024.jpg 1024w, /assets/pic_1980.jpg 1980w" sizes="100vw">
+      #
+      # Active Storage (images that are uploaded by the users of your app):
+      #
+      #   image_tag(user.avatar)
+      #   # => <img src="/rails/active_storage/blobs/.../tiger.jpg" />
+      #   image_tag(user.avatar.variant(resize: "100x100"))
+      #   # => <img src="/rails/active_storage/variants/.../tiger.jpg" />
+      #   image_tag(user.avatar.variant(resize: "100x100"), size: '100')
+      #   # => <img width="100" height="100" src="/rails/active_storage/variants/.../tiger.jpg" />
+      def image_tag(source, options = {})
         options = options.symbolize_keys
         check_for_image_tag_errors(options)
+        skip_pipeline = options.delete(:skip_pipeline)
 
-        src = options[:src] = path_to_image(source)
+        options[:src] = resolve_image_source(source, skip_pipeline)
 
-        unless src =~ /^(?:cid|data):/ || src.blank?
-          options[:alt] = options.fetch(:alt){ image_alt(src) }
+        if options[:srcset] && !options[:srcset].is_a?(String)
+          options[:srcset] = options[:srcset].map do |src_path, size|
+            src_path = path_to_image(src_path, skip_pipeline: skip_pipeline)
+            "#{src_path} #{size}"
+          end.join(", ")
         end
 
         options[:width], options[:height] = extract_dimensions(options.delete(:size)) if options[:size]
@@ -239,7 +365,9 @@ module ActionView
       #   image_alt('underscored_file_name.png')
       #   # => Underscored file name
       def image_alt(src)
-        File.basename(src, '.*'.freeze).sub(/-[[:xdigit:]]{32,64}\z/, ''.freeze).tr('-_'.freeze, ' '.freeze).capitalize
+        ActiveSupport::Deprecation.warn("image_alt is deprecated and will be removed from Rails 6.0. You must explicitly set alt text on images.")
+
+        File.basename(src, ".*".freeze).sub(/-[[:xdigit:]]{32,64}\z/, "".freeze).tr("-_".freeze, " ".freeze).capitalize
       end
 
       # Returns an HTML video tag for the +sources+. If +sources+ is a string,
@@ -257,6 +385,8 @@ module ActionView
       # * <tt>:size</tt> - Supplied as "{Width}x{Height}" or "{Number}", so "30x45" becomes
       #   width="30" and height="45", and "50" becomes width="50" and height="50".
       #   <tt>:size</tt> will be ignored if the value is not in the correct format.
+      # * <tt>:poster_skip_pipeline</tt> will bypass the asset pipeline when using
+      #   the <tt>:poster</tt> option instead using an asset in the public folder.
       #
       # ==== Examples
       #
@@ -264,10 +394,12 @@ module ActionView
       #   # => <video src="/videos/trailer"></video>
       #   video_tag("trailer.ogg")
       #   # => <video src="/videos/trailer.ogg"></video>
-      #   video_tag("trailer.ogg", controls: true, autobuffer: true)
-      #   # => <video autobuffer="autobuffer" controls="controls" src="/videos/trailer.ogg" ></video>
+      #   video_tag("trailer.ogg", controls: true, preload: 'none')
+      #   # => <video preload="none" controls="controls" src="/videos/trailer.ogg" ></video>
       #   video_tag("trailer.m4v", size: "16x10", poster: "screenshot.png")
       #   # => <video src="/videos/trailer.m4v" width="16" height="10" poster="/assets/screenshot.png"></video>
+      #   video_tag("trailer.m4v", size: "16x10", poster: "screenshot.png", poster_skip_pipeline: true)
+      #   # => <video src="/videos/trailer.m4v" width="16" height="10" poster="screenshot.png"></video>
       #   video_tag("/trailers/hd.avi", size: "16x16")
       #   # => <video src="/trailers/hd.avi" width="16" height="16"></video>
       #   video_tag("/trailers/hd.avi", size: "16")
@@ -281,9 +413,12 @@ module ActionView
       #   video_tag(["trailer.ogg", "trailer.flv"], size: "160x120")
       #   # => <video height="120" width="160"><source src="/videos/trailer.ogg" /><source src="/videos/trailer.flv" /></video>
       def video_tag(*sources)
-        multiple_sources_tag('video', sources) do |options|
-          options[:poster] = path_to_image(options[:poster]) if options[:poster]
-          options[:width], options[:height] = extract_dimensions(options.delete(:size)) if options[:size]
+        options = sources.extract_options!.symbolize_keys
+        public_poster_folder = options.delete(:poster_skip_pipeline)
+        sources << options
+        multiple_sources_tag_builder("video", sources) do |tag_options|
+          tag_options[:poster] = path_to_image(tag_options[:poster], skip_pipeline: public_poster_folder) if tag_options[:poster]
+          tag_options[:width], tag_options[:height] = extract_dimensions(tag_options.delete(:size)) if tag_options[:size]
         end
       end
 
@@ -300,31 +435,42 @@ module ActionView
       #   audio_tag("sound.wav", "sound.mid")
       #   # => <audio><source src="/audios/sound.wav" /><source src="/audios/sound.mid" /></audio>
       def audio_tag(*sources)
-        multiple_sources_tag('audio', sources)
+        multiple_sources_tag_builder("audio", sources)
       end
 
       private
-        def multiple_sources_tag(type, sources)
-          options = sources.extract_options!.symbolize_keys
+        def multiple_sources_tag_builder(type, sources)
+          options       = sources.extract_options!.symbolize_keys
+          skip_pipeline = options.delete(:skip_pipeline)
           sources.flatten!
 
           yield options if block_given?
 
           if sources.size > 1
             content_tag(type, options) do
-              safe_join sources.map { |source| tag("source", :src => send("path_to_#{type}", source)) }
+              safe_join sources.map { |source| tag("source", src: send("path_to_#{type}", source, skip_pipeline: skip_pipeline)) }
             end
           else
-            options[:src] = send("path_to_#{type}", sources.first)
+            options[:src] = send("path_to_#{type}", sources.first, skip_pipeline: skip_pipeline)
             content_tag(type, nil, options)
           end
         end
 
+        def resolve_image_source(source, skip_pipeline)
+          if source.is_a?(Symbol) || source.is_a?(String)
+            path_to_image(source, skip_pipeline: skip_pipeline)
+          else
+            polymorphic_url(source)
+          end
+        rescue NoMethodError => e
+          raise ArgumentError, "Can't resolve image into URL: #{e}"
+        end
+
         def extract_dimensions(size)
           size = size.to_s
-          if size =~ %r{\A\d+x\d+\z}
-            size.split('x')
-          elsif size =~ %r{\A\d+\z}
+          if /\A\d+x\d+\z/.match?(size)
+            size.split("x")
+          elsif /\A\d+\z/.match?(size)
             [size, size]
           end
         end
@@ -334,6 +480,18 @@ module ActionView
             raise ArgumentError, "Cannot pass a :size option with a :height or :width option"
           end
         end
+
+        def resolve_link_as(extname, mime_type)
+          if extname == "js"
+            "script"
+          elsif extname == "css"
+            "style"
+          elsif extname == "vtt"
+            "track"
+          elsif (type = mime_type.to_s.split("/")[0]) && type.in?(%w(audio video font))
+            type
+          end
+        end
     end
   end
 end
diff --git a/actionview/lib/action_view/helpers/asset_url_helper.rb b/actionview/lib/action_view/helpers/asset_url_helper.rb
index 717b326740..f7690104ee 100644
--- a/actionview/lib/action_view/helpers/asset_url_helper.rb
+++ b/actionview/lib/action_view/helpers/asset_url_helper.rb
@@ -1,8 +1,10 @@
-require 'zlib'
+# frozen_string_literal: true
+
+require "zlib"
 
 module ActionView
   # = Action View Asset URL Helpers
-  module Helpers
+  module Helpers #:nodoc:
     # This module provides methods for generating asset paths and
     # urls.
     #
@@ -27,7 +29,7 @@ module ActionView
     # Helpers take that into account:
     #
     #   image_tag("rails.png")
-    #   # => <img alt="Rails" src="http://assets.example.com/assets/rails.png" />
+    #   # => <img src="http://assets.example.com/assets/rails.png" />
     #   stylesheet_link_tag("application")
     #   # => <link href="http://assets.example.com/assets/application.css" media="screen" rel="stylesheet" />
     #
@@ -36,11 +38,11 @@ module ActionView
     # some asset downloads to wait for previous assets to finish before they can
     # begin. You can use the <tt>%d</tt> wildcard in the +asset_host+ to
     # distribute the requests over four hosts. For example,
-    # <tt>assets%d.example.com<tt> will spread the asset requests over
+    # <tt>assets%d.example.com</tt> will spread the asset requests over
     # "assets0.example.com", ..., "assets3.example.com".
     #
     #   image_tag("rails.png")
-    #   # => <img alt="Rails" src="http://assets0.example.com/assets/rails.png" />
+    #   # => <img src="http://assets0.example.com/assets/rails.png" />
     #   stylesheet_link_tag("application")
     #   # => <link href="http://assets2.example.com/assets/application.css" media="screen" rel="stylesheet" />
     #
@@ -66,7 +68,7 @@ module ActionView
     #     "http://assets#{Digest::MD5.hexdigest(source).to_i(16) % 2 + 1}.example.com"
     #   }
     #   image_tag("rails.png")
-    #   # => <img alt="Rails" src="http://assets1.example.com/assets/rails.png" />
+    #   # => <img src="http://assets1.example.com/assets/rails.png" />
     #   stylesheet_link_tag("application")
     #   # => <link href="http://assets2.example.com/assets/application.css" media="screen" rel="stylesheet" />
     #
@@ -85,7 +87,7 @@ module ActionView
     #      end
     #    }
     #   image_tag("rails.png")
-    #   # => <img alt="Rails" src="http://assets.example.com/assets/rails.png" />
+    #   # => <img src="http://assets.example.com/assets/rails.png" />
     #   stylesheet_link_tag("application")
     #   # => <link href="http://stylesheets.example.com/assets/application.css" media="screen" rel="stylesheet" />
     #
@@ -96,8 +98,8 @@ module ActionView
     # have SSL certificates for each of the asset hosts this technique allows you
     # to avoid warnings in the client about mixed media.
     # Note that the request parameter might not be supplied, e.g. when the assets
-    # are precompiled via a Rake task. Make sure to use a Proc instead of a lambda,
-    # since a Proc allows missing parameters and sets them to nil.
+    # are precompiled via a Rake task. Make sure to use a +Proc+ instead of a lambda,
+    # since a +Proc+ allows missing parameters and sets them to +nil+.
     #
     #   config.action_controller.asset_host = Proc.new { |source, request|
     #     if request && request.ssl?
@@ -117,31 +119,86 @@ module ActionView
     module AssetUrlHelper
       URI_REGEXP = %r{^[-a-z]+://|^(?:cid|data):|^//}i
 
-      # Computes the path to asset in public directory. If :type
-      # options is set, a file extension will be appended and scoped
-      # to the corresponding public directory.
+      # This is the entry point for all assets.
+      # When using the asset pipeline (i.e. sprockets and sprockets-rails), the
+      # behavior is "enhanced". You can bypass the asset pipeline by passing in
+      # <tt>skip_pipeline: true</tt> to the options.
       #
       # All other asset *_path helpers delegate through this method.
       #
-      #   asset_path "application.js"                     # => /assets/application.js
-      #   asset_path "application", type: :javascript     # => /assets/application.js
-      #   asset_path "application", type: :stylesheet     # => /assets/application.css
-      #   asset_path "http://www.example.com/js/xmlhr.js" # => http://www.example.com/js/xmlhr.js
+      # === With the asset pipeline
+      #
+      # All options passed to +asset_path+ will be passed to +compute_asset_path+
+      # which is implemented by sprockets-rails.
+      #
+      #   asset_path("application.js") # => "/assets/application-60aa4fdc5cea14baf5400fba1abf4f2a46a5166bad4772b1effe341570f07de9.js"
+      #
+      # === Without the asset pipeline (<tt>skip_pipeline: true</tt>)
+      #
+      # Accepts a <tt>type</tt> option that can specify the asset's extension. No error
+      # checking is done to verify the source passed into +asset_path+ is valid
+      # and that the file exists on disk.
+      #
+      #   asset_path("application.js", skip_pipeline: true)                 # => "application.js"
+      #   asset_path("filedoesnotexist.png", skip_pipeline: true)           # => "filedoesnotexist.png"
+      #   asset_path("application", type: :javascript, skip_pipeline: true) # => "/javascripts/application.js"
+      #   asset_path("application", type: :stylesheet, skip_pipeline: true) # => "/stylesheets/application.css"
+      #
+      # === Options applying to all assets
+      #
+      # Below lists scenarios that apply to +asset_path+ whether or not you're
+      # using the asset pipeline.
+      #
+      # - All fully qualified urls are returned immediately. This bypasses the
+      #   asset pipeline and all other behavior described.
+      #
+      #     asset_path("http://www.example.com/js/xmlhr.js") # => "http://www.example.com/js/xmlhr.js"
+      #
+      # - All assets that begin with a forward slash are assumed to be full
+      #   urls and will not be expanded. This will bypass the asset pipeline.
+      #
+      #     asset_path("/foo.png") # => "/foo.png"
+      #
+      # - All blank strings will be returned immediately. This bypasses the
+      #   asset pipeline and all other behavior described.
+      #
+      #     asset_path("") # => ""
+      #
+      # - If <tt>config.relative_url_root</tt> is specified, all assets will have that
+      #   root prepended.
+      #
+      #     Rails.application.config.relative_url_root = "bar"
+      #     asset_path("foo.js", skip_pipeline: true) # => "bar/foo.js"
+      #
+      # - A different asset host can be specified via <tt>config.action_controller.asset_host</tt>
+      #   this is commonly used in conjunction with a CDN.
+      #
+      #     Rails.application.config.action_controller.asset_host = "assets.example.com"
+      #     asset_path("foo.js", skip_pipeline: true) # => "http://assets.example.com/foo.js"
+      #
+      # - An extension name can be specified manually with <tt>extname</tt>.
+      #
+      #     asset_path("foo", skip_pipeline: true, extname: ".js")     # => "/foo.js"
+      #     asset_path("foo.css", skip_pipeline: true, extname: ".js") # => "/foo.css.js"
       def asset_path(source, options = {})
         raise ArgumentError, "nil is not a valid asset source" if source.nil?
 
         source = source.to_s
-        return "" unless source.present?
-        return source if source =~ URI_REGEXP
+        return "" if source.blank?
+        return source if URI_REGEXP.match?(source)
 
-        tail, source = source[/([\?#].+)$/], source.sub(/([\?#].+)$/, ''.freeze)
+        tail, source = source[/([\?#].+)$/], source.sub(/([\?#].+)$/, "".freeze)
 
         if extname = compute_asset_extname(source, options)
           source = "#{source}#{extname}"
         end
 
         if source[0] != ?/
-          source = compute_asset_path(source, options)
+          if options[:skip_pipeline]
+            source = public_compute_asset_path(source, options)
+          else
+            source = compute_asset_path(source, options)
+          end
         end
 
         relative_url_root = defined?(config.relative_url_root) && config.relative_url_root
@@ -168,31 +225,35 @@ module ActionView
       #   asset_url "application.js", host: "http://cdn.example.com" # => http://cdn.example.com/assets/application.js
       #
       def asset_url(source, options = {})
-        path_to_asset(source, options.merge(:protocol => :request))
+        path_to_asset(source, options.merge(protocol: :request))
       end
       alias_method :url_to_asset, :asset_url # aliased to avoid conflicts with an asset_url named route
 
       ASSET_EXTENSIONS = {
-        javascript: '.js',
-        stylesheet: '.css'
+        javascript: ".js",
+        stylesheet: ".css"
       }
 
-      # Compute extname to append to asset path. Returns nil if
+      # Compute extname to append to asset path. Returns +nil+ if
       # nothing should be added.
       def compute_asset_extname(source, options = {})
         return if options[:extname] == false
         extname = options[:extname] || ASSET_EXTENSIONS[options[:type]]
-        extname if extname && File.extname(source) != extname
+        if extname && File.extname(source) != extname
+          extname
+        else
+          nil
+        end
       end
 
       # Maps asset types to public directory.
       ASSET_PUBLIC_DIRECTORIES = {
-        audio:      '/audios',
-        font:       '/fonts',
-        image:      '/images',
-        javascript: '/javascripts',
-        stylesheet: '/stylesheets',
-        video:      '/videos'
+        audio:      "/audios",
+        font:       "/fonts",
+        image:      "/images",
+        javascript: "/javascripts",
+        stylesheet: "/stylesheets",
+        video:      "/videos"
       }
 
       # Computes asset path to public directory. Plugins and
@@ -202,6 +263,7 @@ module ActionView
         dir = ASSET_PUBLIC_DIRECTORIES[options[:type]] || ""
         File.join(dir, source)
       end
+      alias :public_compute_asset_path :compute_asset_path
 
       # Pick an asset host for this source. Returns +nil+ if no host is set,
       # the host if no wildcard is set, the host interpolated with the
@@ -213,19 +275,21 @@ module ActionView
         host = options[:host]
         host ||= config.asset_host if defined? config.asset_host
 
-        if host.respond_to?(:call)
-          arity = host.respond_to?(:arity) ? host.arity : host.method(:call).arity
-          args = [source]
-          args << request if request && (arity > 1 || arity < 0)
-          host = host.call(*args)
-        elsif host =~ /%d/
-          host = host % (Zlib.crc32(source) % 4)
+        if host
+          if host.respond_to?(:call)
+            arity = host.respond_to?(:arity) ? host.arity : host.method(:call).arity
+            args = [source]
+            args << request if request && (arity > 1 || arity < 0)
+            host = host.call(*args)
+          elsif host.include?("%d")
+            host = host % (Zlib.crc32(source) % 4)
+          end
         end
 
         host ||= request.base_url if request && options[:protocol] == :request
         return unless host
 
-        if host =~ URI_REGEXP
+        if URI_REGEXP.match?(host)
           host
         else
           protocol = options[:protocol] || config.default_asset_host_protocol || (request ? :request : :relative)
@@ -251,7 +315,7 @@ module ActionView
       #   javascript_path "http://www.example.com/js/xmlhr"    # => http://www.example.com/js/xmlhr
       #   javascript_path "http://www.example.com/js/xmlhr.js" # => http://www.example.com/js/xmlhr.js
       def javascript_path(source, options = {})
-        path_to_asset(source, {type: :javascript}.merge!(options))
+        path_to_asset(source, { type: :javascript }.merge!(options))
       end
       alias_method :path_to_javascript, :javascript_path # aliased to avoid conflicts with a javascript_path named route
 
@@ -260,10 +324,10 @@ module ActionView
       # Since +javascript_url+ is based on +asset_url+ method you can set :host options. If :host
       # options is set, it overwrites global +config.action_controller.asset_host+ setting.
       #
-      #   javascript_url "js/xmlhr.js", host: "http://stage.example.com" # => http://stage.example.com/assets/dir/xmlhr.js
+      #   javascript_url "js/xmlhr.js", host: "http://stage.example.com" # => http://stage.example.com/assets/js/xmlhr.js
       #
       def javascript_url(source, options = {})
-        url_to_asset(source, {type: :javascript}.merge!(options))
+        url_to_asset(source, { type: :javascript }.merge!(options))
       end
       alias_method :url_to_javascript, :javascript_url # aliased to avoid conflicts with a javascript_url named route
 
@@ -278,7 +342,7 @@ module ActionView
       #   stylesheet_path "http://www.example.com/css/style"       # => http://www.example.com/css/style
       #   stylesheet_path "http://www.example.com/css/style.css"   # => http://www.example.com/css/style.css
       def stylesheet_path(source, options = {})
-        path_to_asset(source, {type: :stylesheet}.merge!(options))
+        path_to_asset(source, { type: :stylesheet }.merge!(options))
       end
       alias_method :path_to_stylesheet, :stylesheet_path # aliased to avoid conflicts with a stylesheet_path named route
 
@@ -287,10 +351,10 @@ module ActionView
       # Since +stylesheet_url+ is based on +asset_url+ method you can set :host options. If :host
       # options is set, it overwrites global +config.action_controller.asset_host+ setting.
       #
-      #   stylesheet_url "css/style.css", host: "http://stage.example.com" # => http://stage.example.com/css/style.css
+      #   stylesheet_url "css/style.css", host: "http://stage.example.com" # => http://stage.example.com/assets/css/style.css
       #
       def stylesheet_url(source, options = {})
-        url_to_asset(source, {type: :stylesheet}.merge!(options))
+        url_to_asset(source, { type: :stylesheet }.merge!(options))
       end
       alias_method :url_to_stylesheet, :stylesheet_url # aliased to avoid conflicts with a stylesheet_url named route
 
@@ -308,7 +372,7 @@ module ActionView
       # The alias +path_to_image+ is provided to avoid that. Rails uses the alias internally, and
       # plugin authors are encouraged to do so.
       def image_path(source, options = {})
-        path_to_asset(source, {type: :image}.merge!(options))
+        path_to_asset(source, { type: :image }.merge!(options))
       end
       alias_method :path_to_image, :image_path # aliased to avoid conflicts with an image_path named route
 
@@ -317,10 +381,10 @@ module ActionView
       # Since +image_url+ is based on +asset_url+ method you can set :host options. If :host
       # options is set, it overwrites global +config.action_controller.asset_host+ setting.
       #
-      #   image_url "edit.png", host: "http://stage.example.com" # => http://stage.example.com/edit.png
+      #   image_url "edit.png", host: "http://stage.example.com" # => http://stage.example.com/assets/edit.png
       #
       def image_url(source, options = {})
-        url_to_asset(source, {type: :image}.merge!(options))
+        url_to_asset(source, { type: :image }.merge!(options))
       end
       alias_method :url_to_image, :image_url # aliased to avoid conflicts with an image_url named route
 
@@ -334,7 +398,7 @@ module ActionView
       #   video_path("/trailers/hd.avi")                              # => /trailers/hd.avi
       #   video_path("http://www.example.com/vid/hd.avi")             # => http://www.example.com/vid/hd.avi
       def video_path(source, options = {})
-        path_to_asset(source, {type: :video}.merge!(options))
+        path_to_asset(source, { type: :video }.merge!(options))
       end
       alias_method :path_to_video, :video_path # aliased to avoid conflicts with a video_path named route
 
@@ -343,12 +407,12 @@ module ActionView
       # Since +video_url+ is based on +asset_url+ method you can set :host options. If :host
       # options is set, it overwrites global +config.action_controller.asset_host+ setting.
       #
-      #   video_url "hd.avi", host: "http://stage.example.com" # => http://stage.example.com/hd.avi
+      #   video_url "hd.avi", host: "http://stage.example.com" # => http://stage.example.com/videos/hd.avi
       #
       def video_url(source, options = {})
-        url_to_asset(source, {type: :video}.merge!(options))
+        url_to_asset(source, { type: :video }.merge!(options))
       end
-      alias_method :url_to_video, :video_url # aliased to avoid conflicts with an video_url named route
+      alias_method :url_to_video, :video_url # aliased to avoid conflicts with a video_url named route
 
       # Computes the path to an audio asset in the public audios directory.
       # Full paths from the document root will be passed through.
@@ -360,7 +424,7 @@ module ActionView
       #   audio_path("/sounds/horse.wav")                                # => /sounds/horse.wav
       #   audio_path("http://www.example.com/sounds/horse.wav")          # => http://www.example.com/sounds/horse.wav
       def audio_path(source, options = {})
-        path_to_asset(source, {type: :audio}.merge!(options))
+        path_to_asset(source, { type: :audio }.merge!(options))
       end
       alias_method :path_to_audio, :audio_path # aliased to avoid conflicts with an audio_path named route
 
@@ -369,10 +433,10 @@ module ActionView
       # Since +audio_url+ is based on +asset_url+ method you can set :host options. If :host
       # options is set, it overwrites global +config.action_controller.asset_host+ setting.
       #
-      #   audio_url "horse.wav", host: "http://stage.example.com" # => http://stage.example.com/horse.wav
+      #   audio_url "horse.wav", host: "http://stage.example.com" # => http://stage.example.com/audios/horse.wav
       #
       def audio_url(source, options = {})
-        url_to_asset(source, {type: :audio}.merge!(options))
+        url_to_asset(source, { type: :audio }.merge!(options))
       end
       alias_method :url_to_audio, :audio_url # aliased to avoid conflicts with an audio_url named route
 
@@ -385,21 +449,21 @@ module ActionView
       #   font_path("/dir/font.ttf")                                  # => /dir/font.ttf
       #   font_path("http://www.example.com/dir/font.ttf")            # => http://www.example.com/dir/font.ttf
       def font_path(source, options = {})
-        path_to_asset(source, {type: :font}.merge!(options))
+        path_to_asset(source, { type: :font }.merge!(options))
       end
-      alias_method :path_to_font, :font_path # aliased to avoid conflicts with an font_path named route
+      alias_method :path_to_font, :font_path # aliased to avoid conflicts with a font_path named route
 
       # Computes the full URL to a font asset.
       # This will use +font_path+ internally, so most of their behaviors will be the same.
       # Since +font_url+ is based on +asset_url+ method you can set :host options. If :host
       # options is set, it overwrites global +config.action_controller.asset_host+ setting.
       #
-      #   font_url "font.ttf", host: "http://stage.example.com" # => http://stage.example.com/font.ttf
+      #   font_url "font.ttf", host: "http://stage.example.com" # => http://stage.example.com/fonts/font.ttf
       #
       def font_url(source, options = {})
-        url_to_asset(source, {type: :font}.merge!(options))
+        url_to_asset(source, { type: :font }.merge!(options))
       end
-      alias_method :url_to_font, :font_url # aliased to avoid conflicts with an font_url named route
+      alias_method :url_to_font, :font_url # aliased to avoid conflicts with a font_url named route
     end
   end
 end
diff --git a/actionview/lib/action_view/helpers/atom_feed_helper.rb b/actionview/lib/action_view/helpers/atom_feed_helper.rb
index c875f5870f..e6b9878271 100644
--- a/actionview/lib/action_view/helpers/atom_feed_helper.rb
+++ b/actionview/lib/action_view/helpers/atom_feed_helper.rb
@@ -1,8 +1,10 @@
-require 'set'
+# frozen_string_literal: true
+
+require "set"
 
 module ActionView
   # = Action View Atom Feed Helpers
-  module Helpers
+  module Helpers #:nodoc:
     module AtomFeedHelper
       # Adds easy defaults to writing Atom feeds with the Builder template engine (this does not work on ERB or any other
       # template languages).
@@ -103,7 +105,7 @@ module ActionView
         xml = options.delete(:xml) || eval("xml", block.binding)
         xml.instruct!
         if options[:instruct]
-          options[:instruct].each do |target,attrs|
+          options[:instruct].each do |target, attrs|
             if attrs.respond_to?(:keys)
               xml.instruct!(target, attrs)
             elsif attrs.respond_to?(:each)
@@ -112,13 +114,13 @@ module ActionView
           end
         end
 
-        feed_opts = {"xml:lang" => options[:language] || "en-US", "xmlns" => 'http://www.w3.org/2005/Atom'}
-        feed_opts.merge!(options).reject!{|k,v| !k.to_s.match(/^xml/)}
+        feed_opts = { "xml:lang" => options[:language] || "en-US", "xmlns" => "http://www.w3.org/2005/Atom" }
+        feed_opts.merge!(options).reject! { |k, v| !k.to_s.match(/^xml/) }
 
         xml.feed(feed_opts) do
           xml.id(options[:id] || "tag:#{request.host},#{options[:schema_date]}:#{request.fullpath.split(".")[0]}")
-          xml.link(:rel => 'alternate', :type => 'text/html', :href => options[:root_url] || (request.protocol + request.host_with_port))
-          xml.link(:rel => 'self', :type => 'application/atom+xml', :href => options[:url] || request.url)
+          xml.link(rel: "alternate", type: "text/html", href: options[:root_url] || (request.protocol + request.host_with_port))
+          xml.link(rel: "self", type: "application/atom+xml", href: options[:url] || request.url)
 
           yield AtomFeedBuilder.new(xml, self, options)
         end
@@ -138,7 +140,7 @@ module ActionView
           def method_missing(method, *arguments, &block)
             if xhtml_block?(method, arguments)
               @xml.__send__(method, *arguments) do
-                @xml.div(:xmlns => 'http://www.w3.org/1999/xhtml') do |xhtml|
+                @xml.div(xmlns: "http://www.w3.org/1999/xhtml") do |xhtml|
                   block.call(xhtml)
                 end
               end
@@ -153,7 +155,7 @@ module ActionView
           def xhtml_block?(method, arguments)
             if XHTML_TAG_NAMES.include?(method.to_s)
               last = arguments.last
-              last.is_a?(Hash) && last[:type].to_s == 'xhtml'
+              last.is_a?(Hash) && last[:type].to_s == "xhtml"
             end
           end
       end
@@ -163,7 +165,7 @@ module ActionView
           @xml, @view, @feed_options = xml, view, feed_options
         end
 
-        # Accepts a Date or Time object and inserts it in the proper format. If nil is passed, current time in UTC is used.
+        # Accepts a Date or Time object and inserts it in the proper format. If +nil+ is passed, current time in UTC is used.
         def updated(date_or_time = nil)
           @xml.updated((date_or_time || Time.now.utc).xmlschema)
         end
@@ -174,7 +176,7 @@ module ActionView
         #
         # * <tt>:published</tt>: Time first published. Defaults to the created_at attribute on the record if one such exists.
         # * <tt>:updated</tt>: Time of update. Defaults to the updated_at attribute on the record if one such exists.
-        # * <tt>:url</tt>: The URL for this entry or false or nil for not having a link tag. Defaults to the polymorphic_url for the record.
+        # * <tt>:url</tt>: The URL for this entry or +false+ or +nil+ for not having a link tag. Defaults to the +polymorphic_url+ for the record.
         # * <tt>:id</tt>: The ID for this entry. Defaults to "tag:#{@view.request.host},#{@feed_options[:schema_date]}:#{record.class}/#{record.id}"
         # * <tt>:type</tt>: The TYPE for this entry. Defaults to "text/html".
         def entry(record, options = {})
@@ -189,16 +191,15 @@ module ActionView
               @xml.updated((options[:updated] || record.updated_at).xmlschema)
             end
 
-            type = options.fetch(:type, 'text/html')
+            type = options.fetch(:type, "text/html")
 
             url = options.fetch(:url) { @view.polymorphic_url(record) }
-            @xml.link(:rel => 'alternate', :type => type, :href => url) if url
+            @xml.link(rel: "alternate", type: type, href: url) if url
 
             yield AtomBuilder.new(@xml)
           end
         end
       end
-
     end
   end
 end
diff --git a/actionview/lib/action_view/helpers/cache_helper.rb b/actionview/lib/action_view/helpers/cache_helper.rb
index 4eaaa239e2..3cbb1ed1a7 100644
--- a/actionview/lib/action_view/helpers/cache_helper.rb
+++ b/actionview/lib/action_view/helpers/cache_helper.rb
@@ -1,6 +1,8 @@
+# frozen_string_literal: true
+
 module ActionView
   # = Action View Cache Helper
-  module Helpers
+  module Helpers #:nodoc:
     module CacheHelper
       # This helper exposes a method for caching fragments of a view
       # rather than an entire action or page. This technique is useful
@@ -8,10 +10,9 @@ module ActionView
       # fragments, and so on. This method takes a block that contains
       # the content you wish to cache.
       #
-      # The best way to use this is by doing key-based cache expiration
-      # on top of a cache store like Memcached that'll automatically
-      # kick out old entries. For more on key-based expiration, see:
-      # http://signalvnoise.com/posts/3113-how-key-based-cache-expiration-works
+      # The best way to use this is by doing recyclable key-based cache expiration
+      # on top of a cache store like Memcached or Redis that'll automatically
+      # kick out old entries.
       #
       # When using this method, you list the cache dependency as the name of the cache, like so:
       #
@@ -23,10 +24,14 @@ module ActionView
       # This approach will assume that when a new topic is added, you'll touch
       # the project. The cache key generated from this call will be something like:
       #
-      #   views/projects/123-20120806214154/7a1156131a6928cb0026877f8b749ac9
-      #         ^class   ^id ^updated_at    ^template tree digest
+      #   views/template/action.html.erb:7a1156131a6928cb0026877f8b749ac9/projects/123
+      #         ^template path           ^template tree digest            ^class   ^id
       #
-      # The cache is thus automatically bumped whenever the project updated_at is touched.
+      # This cache key is stable, but it's combined with a cache version derived from the project
+      # record. When the project updated_at is touched, the #cache_version changes, even
+      # if the key stays stable. This means that unlike a traditional key-based cache expiration
+      # approach, you won't be generating cache trash, unused keys, simply because the dependent
+      # record is updated.
       #
       # If your template cache depends on multiple sources (try to avoid this to keep things simple),
       # you can name all these dependencies as part of an array:
@@ -69,11 +74,11 @@ module ActionView
       #   render 'comments/comments'
       #   render('comments/comments')
       #
-      #   render "header" => render("comments/header")
+      #   render "header" translates to render("comments/header")
       #
-      #   render(@topic)         => render("topics/topic")
-      #   render(topics)         => render("topics/topic")
-      #   render(message.topics) => render("topics/topic")
+      #   render(@topic)         translates to render("topics/topic")
+      #   render(topics)         translates to render("topics/topic")
+      #   render(message.topics) translates to render("topics/topic")
       #
       # It's not possible to derive all render calls like that, though.
       # Here are a few examples of things that can't be derived:
@@ -88,7 +93,7 @@ module ActionView
       #
       # === Explicit dependencies
       #
-      # Some times you'll have template dependencies that can't be derived at all. This is typically
+      # Sometimes you'll have template dependencies that can't be derived at all. This is typically
       # the case when you have template rendering that happens in helpers. Here's an example:
       #
       #   <%= render_sortable_todolists @project.todolists %>
@@ -106,9 +111,9 @@ module ActionView
       #   <%= render_categorizable_events @person.events %>
       #
       # This marks every template in the directory as a dependency. To find those
-      # templates, the wildcard path must be absolutely defined from app/views or paths
+      # templates, the wildcard path must be absolutely defined from <tt>app/views</tt> or paths
       # otherwise added with +prepend_view_path+ or +append_view_path+.
-      # This way the wildcard for `app/views/recordings/events` would be `recordings/events/*` etc.
+      # This way the wildcard for <tt>app/views/recordings/events</tt> would be <tt>recordings/events/*</tt> etc.
       #
       # The pattern used to match explicit dependencies is <tt>/# Template Dependency: (\S+)/</tt>,
       # so it's important that you type it out just so.
@@ -128,13 +133,14 @@ module ActionView
       #
       # === Collection Caching
       #
-      # When rendering a collection of objects that each use the same partial, a `cached`
+      # When rendering a collection of objects that each use the same partial, a <tt>:cached</tt>
       # option can be passed.
+      #
       # For collections rendered such:
       #
-      #   <%= render partial: 'notifications/notification', collection: @notifications, cached: true %>
+      #   <%= render partial: 'projects/project', collection: @projects, cached: true %>
       #
-      # The `cached: true` will make Action View's rendering read several templates
+      # The <tt>cached: true</tt> will make Action View's rendering read several templates
       # from cache at once instead of one call per template.
       #
       # Templates in the collection not already cached are written to cache.
@@ -142,13 +148,21 @@ module ActionView
       # Works great alongside individual template fragment caching.
       # For instance if the template the collection renders is cached like:
       #
-      #   # notifications/_notification.html.erb
-      #   <% cache notification do %>
+      #   # projects/_project.html.erb
+      #   <% cache project do %>
       #     <%# ... %>
       #   <% end %>
       #
       # Any collection renders will find those cached templates when attempting
       # to read multiple templates at once.
+      #
+      # If your collection cache depends on multiple sources (try to avoid this to keep things simple),
+      # you can name all these dependencies as part of a block that returns an array:
+      #
+      #   <%= render partial: 'projects/project', collection: @projects, cached: -> project { [ project, current_user ] } %>
+      #
+      # This will include both records as part of the cache key and updating either of them will
+      # expire the cache.
       def cache(name = {}, options = {}, &block)
         if controller.respond_to?(:perform_caching) && controller.perform_caching
           name_options = options.slice(:skip_digest, :virtual_path)
@@ -204,29 +218,37 @@ module ActionView
 
     private
 
-      def fragment_name_with_digest(name, virtual_path) #:nodoc:
+      def fragment_name_with_digest(name, virtual_path)
         virtual_path ||= @virtual_path
+
         if virtual_path
-          name  = controller.url_for(name).split("://").last if name.is_a?(Hash)
-          digest = Digestor.digest name: virtual_path, finder: lookup_context, dependencies: view_cache_dependencies
-          [ name, digest ]
+          name = controller.url_for(name).split("://").last if name.is_a?(Hash)
+
+          if digest = Digestor.digest(name: virtual_path, finder: lookup_context, dependencies: view_cache_dependencies).presence
+            [ "#{virtual_path}:#{digest}", name ]
+          else
+            [ virtual_path, name ]
+          end
         else
           name
         end
       end
 
-      # TODO: Create an object that has caching read/write on it
-      def fragment_for(name = {}, options = nil, &block) #:nodoc:
-        read_fragment_for(name, options) || write_fragment_for(name, options, &block)
+      def fragment_for(name = {}, options = nil, &block)
+        if content = read_fragment_for(name, options)
+          @view_renderer.cache_hits[@virtual_path] = :hit if defined?(@view_renderer)
+          content
+        else
+          @view_renderer.cache_hits[@virtual_path] = :miss if defined?(@view_renderer)
+          write_fragment_for(name, options, &block)
+        end
       end
 
-      def read_fragment_for(name, options) #:nodoc:
+      def read_fragment_for(name, options)
         controller.read_fragment(name, options)
       end
 
-      def write_fragment_for(name, options) #:nodoc:
-        # VIEW TODO: Make #capture usable outside of ERB
-        # This dance is needed because Builder can't use capture
+      def write_fragment_for(name, options)
         pos = output_buffer.length
         yield
         output_safe = output_buffer.html_safe?
diff --git a/actionview/lib/action_view/helpers/capture_helper.rb b/actionview/lib/action_view/helpers/capture_helper.rb
index df8d0affd0..92f7ddb70d 100644
--- a/actionview/lib/action_view/helpers/capture_helper.rb
+++ b/actionview/lib/action_view/helpers/capture_helper.rb
@@ -1,13 +1,15 @@
-require 'active_support/core_ext/string/output_safety'
+# frozen_string_literal: true
+
+require "active_support/core_ext/string/output_safety"
 
 module ActionView
   # = Action View Capture Helper
-  module Helpers
+  module Helpers #:nodoc:
     # CaptureHelper exposes methods to let you extract generated markup which
     # can be used in other parts of a template or layout file.
     #
     # It provides a method to capture blocks into variables through capture and
-    # a way to capture a block of markup for use in a layout through content_for.
+    # a way to capture a block of markup for use in a layout through {content_for}[rdoc-ref:ActionView::Helpers::CaptureHelper#content_for].
     module CaptureHelper
       # The capture method extracts part of a template as a String object.
       # You can then use this object anywhere in your templates, layout, or helpers.
@@ -37,12 +39,12 @@ module ActionView
       def capture(*args)
         value = nil
         buffer = with_output_buffer { value = yield(*args) }
-        if string = buffer.presence || value and string.is_a?(String)
+        if (string = buffer.presence || value) && string.is_a?(String)
           ERB::Util.html_escape string
         end
       end
 
-      # Calling content_for stores a block of markup in an identifier for later use.
+      # Calling <tt>content_for</tt> stores a block of markup in an identifier for later use.
       # In order to access this stored content in other templates, helper modules
       # or the layout, you would pass the identifier as an argument to <tt>content_for</tt>.
       #
@@ -108,7 +110,7 @@ module ActionView
       # That will place +script+ tags for your default set of JavaScript files on the page;
       # this technique is useful if you'll only be using these scripts in a few views.
       #
-      # Note that content_for concatenates (default) the blocks it is given for a particular
+      # Note that <tt>content_for</tt> concatenates (default) the blocks it is given for a particular
       # identifier in order. For example:
       #
       #   <% content_for :navigation do %>
@@ -125,7 +127,7 @@ module ActionView
       #
       #   <ul><%= content_for :navigation %></ul>
       #
-      # If the flush parameter is true content_for replaces the blocks it is given. For example:
+      # If the flush parameter is +true+ <tt>content_for</tt> replaces the blocks it is given. For example:
       #
       #   <% content_for :navigation do %>
       #     <li><%= link_to 'Home', action: 'index' %></li>
@@ -145,7 +147,7 @@ module ActionView
       #
       #   <% content_for :script, javascript_include_tag(:defaults) %>
       #
-      # WARNING: content_for is ignored in caches. So you shouldn't use it for elements that will be fragment cached.
+      # WARNING: <tt>content_for</tt> is ignored in caches. So you shouldn't use it for elements that will be fragment cached.
       def content_for(name, content = nil, options = {}, &block)
         if content || block_given?
           if block_given?
@@ -172,7 +174,7 @@ module ActionView
         result unless content
       end
 
-      # content_for? checks whether any content has been captured yet using `content_for`.
+      # <tt>content_for?</tt> checks whether any content has been captured yet using <tt>content_for</tt>.
       # Useful to render parts of your layout differently based on what is in your views.
       #
       #   <%# This is the layout %>
diff --git a/actionview/lib/action_view/helpers/controller_helper.rb b/actionview/lib/action_view/helpers/controller_helper.rb
index 3569fba8c6..79cf86c7d1 100644
--- a/actionview/lib/action_view/helpers/controller_helper.rb
+++ b/actionview/lib/action_view/helpers/controller_helper.rb
@@ -1,14 +1,19 @@
-require 'active_support/core_ext/module/attr_internal'
+# frozen_string_literal: true
+
+require "active_support/core_ext/module/attr_internal"
 
 module ActionView
-  module Helpers
+  module Helpers #:nodoc:
     # This module keeps all methods and behavior in ActionView
     # that simply delegates to the controller.
     module ControllerHelper #:nodoc:
       attr_internal :controller, :request
 
-      delegate :request_forgery_protection_token, :params, :session, :cookies, :response, :headers,
-               :flash, :action_name, :controller_name, :controller_path, :to => :controller
+      CONTROLLER_DELEGATES = [:request_forgery_protection_token, :params,
+        :session, :cookies, :response, :headers, :flash, :action_name,
+        :controller_name, :controller_path]
+
+      delegate(*CONTROLLER_DELEGATES, to: :controller)
 
       def assign_controller(controller)
         if @_controller = controller
@@ -21,6 +26,11 @@ module ActionView
       def logger
         controller.logger if controller.respond_to?(:logger)
       end
+
+      def respond_to?(method_name, include_private = false)
+        return controller.respond_to?(method_name) if CONTROLLER_DELEGATES.include?(method_name.to_sym)
+        super
+      end
     end
   end
 end
diff --git a/actionview/lib/action_view/helpers/csrf_helper.rb b/actionview/lib/action_view/helpers/csrf_helper.rb
index 5af92c4ff2..69c59844a6 100644
--- a/actionview/lib/action_view/helpers/csrf_helper.rb
+++ b/actionview/lib/action_view/helpers/csrf_helper.rb
@@ -1,6 +1,8 @@
+# frozen_string_literal: true
+
 module ActionView
   # = Action View CSRF Helper
-  module Helpers
+  module Helpers #:nodoc:
     module CsrfHelper
       # Returns meta tags "csrf-param" and "csrf-token" with the name of the cross-site
       # request forgery protection parameter and token, respectively.
@@ -14,14 +16,14 @@ module ActionView
       #
       # You don't need to use these tags for regular forms as they generate their own hidden fields.
       #
-      # For AJAX requests other than GETs, extract the "csrf-token" from the meta-tag and send as the 
-      # "X-CSRF-Token" HTTP header. If you are using jQuery with jquery-rails this happens automatically.
+      # For AJAX requests other than GETs, extract the "csrf-token" from the meta-tag and send as the
+      # "X-CSRF-Token" HTTP header. If you are using rails-ujs this happens automatically.
       #
       def csrf_meta_tags
         if protect_against_forgery?
           [
-            tag('meta', :name => 'csrf-param', :content => request_forgery_protection_token),
-            tag('meta', :name => 'csrf-token', :content => form_authenticity_token)
+            tag("meta", name: "csrf-param", content: request_forgery_protection_token),
+            tag("meta", name: "csrf-token", content: form_authenticity_token)
           ].join("\n").html_safe
         end
       end
diff --git a/actionview/lib/action_view/helpers/date_helper.rb b/actionview/lib/action_view/helpers/date_helper.rb
index 04dcf01bb7..09040ccbc4 100644
--- a/actionview/lib/action_view/helpers/date_helper.rb
+++ b/actionview/lib/action_view/helpers/date_helper.rb
@@ -1,13 +1,15 @@
-require 'date'
-require 'action_view/helpers/tag_helper'
-require 'active_support/core_ext/array/extract_options'
-require 'active_support/core_ext/date/conversions'
-require 'active_support/core_ext/hash/slice'
-require 'active_support/core_ext/object/acts_like'
-require 'active_support/core_ext/object/with_options'
+# frozen_string_literal: true
+
+require "date"
+require "action_view/helpers/tag_helper"
+require "active_support/core_ext/array/extract_options"
+require "active_support/core_ext/date/conversions"
+require "active_support/core_ext/hash/slice"
+require "active_support/core_ext/object/acts_like"
+require "active_support/core_ext/object/with_options"
 
 module ActionView
-  module Helpers
+  module Helpers #:nodoc:
     # = Action View Date Helpers
     #
     # The Date Helper primarily creates select/option tags for different kinds of dates and times or date and time
@@ -95,66 +97,62 @@ module ActionView
           scope: :'datetime.distance_in_words'
         }.merge!(options)
 
-        from_time = from_time.to_time if from_time.respond_to?(:to_time)
-        to_time = to_time.to_time if to_time.respond_to?(:to_time)
+        from_time = normalize_distance_of_time_argument_to_time(from_time)
+        to_time = normalize_distance_of_time_argument_to_time(to_time)
         from_time, to_time = to_time, from_time if from_time > to_time
-        distance_in_minutes = ((to_time - from_time)/60.0).round
+        distance_in_minutes = ((to_time - from_time) / 60.0).round
         distance_in_seconds = (to_time - from_time).round
 
-        I18n.with_options :locale => options[:locale], :scope => options[:scope] do |locale|
+        I18n.with_options locale: options[:locale], scope: options[:scope] do |locale|
           case distance_in_minutes
-            when 0..1
-              return distance_in_minutes == 0 ?
-                     locale.t(:less_than_x_minutes, :count => 1) :
-                     locale.t(:x_minutes, :count => distance_in_minutes) unless options[:include_seconds]
-
-              case distance_in_seconds
-                when 0..4   then locale.t :less_than_x_seconds, :count => 5
-                when 5..9   then locale.t :less_than_x_seconds, :count => 10
-                when 10..19 then locale.t :less_than_x_seconds, :count => 20
-                when 20..39 then locale.t :half_a_minute
-                when 40..59 then locale.t :less_than_x_minutes, :count => 1
-                else             locale.t :x_minutes,           :count => 1
-              end
-
-            when 2...45           then locale.t :x_minutes,      :count => distance_in_minutes
-            when 45...90          then locale.t :about_x_hours,  :count => 1
+          when 0..1
+            return distance_in_minutes == 0 ?
+                   locale.t(:less_than_x_minutes, count: 1) :
+                   locale.t(:x_minutes, count: distance_in_minutes) unless options[:include_seconds]
+
+            case distance_in_seconds
+            when 0..4   then locale.t :less_than_x_seconds, count: 5
+            when 5..9   then locale.t :less_than_x_seconds, count: 10
+            when 10..19 then locale.t :less_than_x_seconds, count: 20
+            when 20..39 then locale.t :half_a_minute
+            when 40..59 then locale.t :less_than_x_minutes, count: 1
+              else             locale.t :x_minutes,           count: 1
+            end
+
+          when 2...45           then locale.t :x_minutes,      count: distance_in_minutes
+          when 45...90          then locale.t :about_x_hours,  count: 1
             # 90 mins up to 24 hours
-            when 90...1440        then locale.t :about_x_hours,  :count => (distance_in_minutes.to_f / 60.0).round
+          when 90...1440        then locale.t :about_x_hours,  count: (distance_in_minutes.to_f / 60.0).round
             # 24 hours up to 42 hours
-            when 1440...2520      then locale.t :x_days,         :count => 1
+          when 1440...2520      then locale.t :x_days,         count: 1
             # 42 hours up to 30 days
-            when 2520...43200     then locale.t :x_days,         :count => (distance_in_minutes.to_f / 1440.0).round
+          when 2520...43200     then locale.t :x_days,         count: (distance_in_minutes.to_f / 1440.0).round
             # 30 days up to 60 days
-            when 43200...86400    then locale.t :about_x_months, :count => (distance_in_minutes.to_f / 43200.0).round
+          when 43200...86400    then locale.t :about_x_months, count: (distance_in_minutes.to_f / 43200.0).round
             # 60 days up to 365 days
-            when 86400...525600   then locale.t :x_months,       :count => (distance_in_minutes.to_f / 43200.0).round
+          when 86400...525600   then locale.t :x_months,       count: (distance_in_minutes.to_f / 43200.0).round
             else
-              if from_time.acts_like?(:time) && to_time.acts_like?(:time)
-                fyear = from_time.year
-                fyear += 1 if from_time.month >= 3
-                tyear = to_time.year
-                tyear -= 1 if to_time.month < 3
-                leap_years = (fyear > tyear) ? 0 : (fyear..tyear).count{|x| Date.leap?(x)}
-                minute_offset_for_leap_year = leap_years * 1440
-                # Discount the leap year days when calculating year distance.
-                # e.g. if there are 20 leap year days between 2 dates having the same day
-                # and month then the based on 365 days calculation
-                # the distance in years will come out to over 80 years when in written
-                # English it would read better as about 80 years.
-                minutes_with_offset = distance_in_minutes - minute_offset_for_leap_year
-              else
-                minutes_with_offset = distance_in_minutes
-              end
-              remainder                   = (minutes_with_offset % MINUTES_IN_YEAR)
-              distance_in_years           = (minutes_with_offset.div MINUTES_IN_YEAR)
-              if remainder < MINUTES_IN_QUARTER_YEAR
-                locale.t(:about_x_years,  :count => distance_in_years)
-              elsif remainder < MINUTES_IN_THREE_QUARTERS_YEAR
-                locale.t(:over_x_years,   :count => distance_in_years)
-              else
-                locale.t(:almost_x_years, :count => distance_in_years + 1)
-              end
+            from_year = from_time.year
+            from_year += 1 if from_time.month >= 3
+            to_year = to_time.year
+            to_year -= 1 if to_time.month < 3
+            leap_years = (from_year > to_year) ? 0 : (from_year..to_year).count { |x| Date.leap?(x) }
+            minute_offset_for_leap_year = leap_years * 1440
+            # Discount the leap year days when calculating year distance.
+            # e.g. if there are 20 leap year days between 2 dates having the same day
+            # and month then the based on 365 days calculation
+            # the distance in years will come out to over 80 years when in written
+            # English it would read better as about 80 years.
+            minutes_with_offset = distance_in_minutes - minute_offset_for_leap_year
+            remainder                   = (minutes_with_offset % MINUTES_IN_YEAR)
+            distance_in_years           = (minutes_with_offset.div MINUTES_IN_YEAR)
+            if remainder < MINUTES_IN_QUARTER_YEAR
+              locale.t(:about_x_years,  count: distance_in_years)
+            elsif remainder < MINUTES_IN_THREE_QUARTERS_YEAR
+              locale.t(:over_x_years,   count: distance_in_years)
+            else
+              locale.t(:almost_x_years, count: distance_in_years + 1)
+            end
           end
         end
       end
@@ -220,7 +218,7 @@ module ActionView
       #   the respective locale (e.g. [:year, :month, :day] in the en locale that ships with Rails).
       # * <tt>:include_blank</tt>     - Include a blank option in every select field so it's possible to set empty
       #   dates.
-      # * <tt>:default</tt>           - Set a default date if the affected date isn't set or is nil.
+      # * <tt>:default</tt>           - Set a default date if the affected date isn't set or is +nil+.
       # * <tt>:selected</tt>          - Set a date that overrides the actual value.
       # * <tt>:disabled</tt>          - Set to true if you want show the select fields as disabled.
       # * <tt>:prompt</tt>            - Set to true (for a generic prompt), a prompt string or a hash of prompt strings
@@ -267,7 +265,7 @@ module ActionView
       #   date_select("article", "written_on", default: 3.days.from_now)
       #
       #   # Generates a date select that when POSTed is stored in the article variable, in the written_on attribute
-      #   # which is set in the form with todays date, regardless of the value in the Active Record object.
+      #   # which is set in the form with today's date, regardless of the value in the Active Record object.
       #   date_select("article", "written_on", selected: Date.today)
       #
       #   # Generates a date select that when POSTed is stored in the credit_card variable, in the bill_due attribute
@@ -303,7 +301,7 @@ module ActionView
       #   # the sunrise attribute.
       #   time_select("article", "start_time", include_seconds: true)
       #
-      #   # You can set the <tt>:minute_step</tt> to 15 which will give you: 00, 15, 30 and 45.
+      #   # You can set the <tt>:minute_step</tt> to 15 which will give you: 00, 15, 30, and 45.
       #   time_select 'game', 'game_time', {minute_step: 15}
       #
       #   # Creates a time select tag with a custom prompt. Use <tt>prompt: true</tt> for generic prompts.
@@ -682,19 +680,31 @@ module ActionView
       def time_tag(date_or_time, *args, &block)
         options  = args.extract_options!
         format   = options.delete(:format) || :long
-        content  = args.first || I18n.l(date_or_time, :format => format)
+        content  = args.first || I18n.l(date_or_time, format: format)
         datetime = date_or_time.acts_like?(:time) ? date_or_time.xmlschema : date_or_time.iso8601
 
-        content_tag("time".freeze, content, options.reverse_merge(:datetime => datetime), &block)
+        content_tag("time".freeze, content, options.reverse_merge(datetime: datetime), &block)
       end
+
+      private
+
+        def normalize_distance_of_time_argument_to_time(value)
+          if value.is_a?(Numeric)
+            Time.at(value)
+          elsif value.respond_to?(:to_time)
+            value.to_time
+          else
+            raise ArgumentError, "#{value.inspect} can't be converted to a Time value"
+          end
+        end
     end
 
     class DateTimeSelector #:nodoc:
       include ActionView::Helpers::TagHelper
 
-      DEFAULT_PREFIX = 'date'.freeze
+      DEFAULT_PREFIX = "date".freeze
       POSITION = {
-        :year => 1, :month => 2, :day => 3, :hour => 4, :minute => 5, :second => 6
+        year: 1, month: 2, day: 3, hour: 4, minute: 5, second: 6
       }.freeze
 
       AMPM_TRANSLATION = Hash[
@@ -710,8 +720,8 @@ module ActionView
         @options      = options.dup
         @html_options = html_options.dup
         @datetime     = datetime
-        @options[:datetime_separator] ||= ' &mdash; '
-        @options[:time_separator]     ||= ' : '
+        @options[:datetime_separator] ||= " &mdash; "
+        @options[:time_separator]     ||= " : "
       end
 
       def select_datetime
@@ -781,7 +791,7 @@ module ActionView
         if @options[:use_hidden] || @options[:discard_minute]
           build_hidden(:minute, min)
         else
-          build_options_and_select(:minute, min, :step => @options[:minute_step])
+          build_options_and_select(:minute, min, step: @options[:minute_step])
         end
       end
 
@@ -801,7 +811,7 @@ module ActionView
         if @options[:use_hidden] || @options[:discard_day]
           build_hidden(:day, day || 1)
         else
-          build_options_and_select(:day, day, :start => 1, :end => 31, :leading_zeros => false, :use_two_digit_numbers => @options[:use_two_digit_numbers])
+          build_options_and_select(:day, day, start: 1, end: 31, leading_zeros: false, use_two_digit_numbers: @options[:use_two_digit_numbers])
         end
       end
 
@@ -811,7 +821,7 @@ module ActionView
         else
           month_options = []
           1.upto(12) do |month_number|
-            options = { :value => month_number }
+            options = { value: month_number }
             options[:selected] = "selected" if month == month_number
             month_options << content_tag("option".freeze, month_name(month_number), options) + "\n"
           end
@@ -821,7 +831,7 @@ module ActionView
 
       def select_year
         if !@datetime || @datetime == 0
-          val = '1'
+          val = "1"
           middle_year = Date.today.year
         else
           val = middle_year = year
@@ -861,12 +871,12 @@ module ActionView
         # valid. Otherwise, February 31st or February 29th, 2011 can be selected, which are invalid.
         def set_day_if_discarded
           if @datetime && @options[:discard_day]
-            @datetime = @datetime.change(:day => 1)
+            @datetime = @datetime.change(day: 1)
           end
         end
 
         # Returns translated month names, but also ensures that a custom month
-        # name array has a leading nil element.
+        # name array has a leading +nil+ element.
         def month_names
           @month_names ||= begin
             month_names = @options[:use_month_names] || translated_month_names
@@ -886,7 +896,7 @@ module ActionView
         #           "Jul", "Aug", "Sep", "Oct", "Nov", "Dec"]
         def translated_month_names
           key = @options[:use_short_month] ? :'date.abbr_month_names' : :'date.month_names'
-          I18n.translate(key, :locale => @options[:locale])
+          I18n.translate(key, locale: @options[:locale])
         end
 
         # Looks up month names by number (1-based):
@@ -914,11 +924,11 @@ module ActionView
           if @options[:use_month_numbers]
             number
           elsif @options[:use_two_digit_numbers]
-            '%02d' % number
+            "%02d" % number
           elsif @options[:add_month_numbers]
             "#{number} - #{month_names[number]}"
           elsif format_string = @options[:month_format_string]
-            format_string % {number: number, name: month_names[number]}
+            format_string % { number: number, name: month_names[number] }
           else
             month_names[number]
           end
@@ -929,7 +939,7 @@ module ActionView
         end
 
         def translated_date_order
-          date_order = I18n.translate(:'date.order', :locale => @options[:locale], :default => [])
+          date_order = I18n.translate(:'date.order', locale: @options[:locale], default: [])
           date_order = date_order.map(&:to_sym)
 
           forbidden_elements = date_order - [:year, :month, :day]
@@ -976,7 +986,7 @@ module ActionView
           select_options = []
           start.step(stop, step) do |i|
             value = leading_zeros ? sprintf("%02d", i) : i
-            tag_options = { :value => value }
+            tag_options = { value: value }
             tag_options[:selected] = "selected" if selected == i
             text = options[:use_two_digit_numbers] ? sprintf("%02d", i) : value
             text = options[:ampm] ? AMPM_TRANSLATION[i] : text
@@ -993,14 +1003,14 @@ module ActionView
         #      </select>"
         def build_select(type, select_options_as_html)
           select_options = {
-            :id => input_id_from_type(type),
-            :name => input_name_from_type(type)
+            id: input_id_from_type(type),
+            name: input_name_from_type(type)
           }.merge!(@html_options)
-          select_options[:disabled] = 'disabled' if @options[:disabled]
+          select_options[:disabled] = "disabled" if @options[:disabled]
           select_options[:class] = css_class_attribute(type, select_options[:class], @options[:with_css_classes]) if @options[:with_css_classes]
 
-          select_html = "\n"
-          select_html << content_tag("option".freeze, '', :value => '') + "\n" if @options[:include_blank]
+          select_html = "\n".dup
+          select_html << content_tag("option".freeze, "", value: "") + "\n" if @options[:include_blank]
           select_html << prompt_option_tag(type, @options[:prompt]) + "\n" if @options[:prompt]
           select_html << select_options_as_html
 
@@ -1011,31 +1021,33 @@ module ActionView
         #  css_class_attribute(:year, 'date optional', { year: 'my-year' })
         #  => "date optional my-year"
         def css_class_attribute(type, html_options_class, options) # :nodoc:
-          css_class = case options
-                      when Hash
-                        options[type.to_sym]
-                      else
-                        type
-                      end
-
-          [html_options_class, css_class].compact.join(' ')
+          css_class = \
+            case options
+            when Hash
+              options[type.to_sym]
+            else
+              type
+            end
+
+          [html_options_class, css_class].compact.join(" ")
         end
 
         # Builds a prompt option tag with supplied options or from default options.
         #  prompt_option_tag(:month, prompt: 'Select month')
         #  => "<option value="">Select month</option>"
         def prompt_option_tag(type, options)
-          prompt = case options
+          prompt = \
+            case options
             when Hash
-              default_options = {:year => false, :month => false, :day => false, :hour => false, :minute => false, :second => false}
+              default_options = { year: false, month: false, day: false, hour: false, minute: false, second: false }
               default_options.merge!(options)[type.to_sym]
             when String
               options
             else
-              I18n.translate(:"datetime.prompts.#{type}", :locale => @options[:locale])
-          end
+              I18n.translate(:"datetime.prompts.#{type}", locale: @options[:locale])
+            end
 
-          prompt ? content_tag("option".freeze, prompt, :value => '') : ''
+          prompt ? content_tag("option".freeze, prompt, value: "") : ""
         end
 
         # Builds hidden input tag for date part and value.
@@ -1043,12 +1055,12 @@ module ActionView
         #  => "<input id="post_written_on_1i" name="post[written_on(1i)]" type="hidden" value="2008" />"
         def build_hidden(type, value)
           select_options = {
-            :type => "hidden",
-            :id => input_id_from_type(type),
-            :name => input_name_from_type(type),
-            :value => value
+            type: "hidden",
+            id: input_id_from_type(type),
+            name: input_name_from_type(type),
+            value: value
           }.merge!(@html_options.slice(:disabled))
-          select_options[:disabled] = 'disabled' if @options[:disabled]
+          select_options[:disabled] = "disabled" if @options[:disabled]
 
           tag(:input, select_options) + "\n".html_safe
         end
@@ -1059,7 +1071,7 @@ module ActionView
           prefix = @options[:prefix] || ActionView::Helpers::DateTimeSelector::DEFAULT_PREFIX
           prefix += "[#{@options[:index]}]" if @options.has_key?(:index)
 
-          field_name = @options[:field_name] || type
+          field_name = @options[:field_name] || type.to_s
           if @options[:include_position]
             field_name += "(#{ActionView::Helpers::DateTimeSelector::POSITION[type]}i)"
           end
@@ -1070,8 +1082,8 @@ module ActionView
         # Returns the id attribute for the input tag.
         #  => "post_written_on_1i"
         def input_id_from_type(type)
-          id = input_name_from_type(type).gsub(/([\[\(])|(\]\[)/, '_').gsub(/[\]\)]/, '')
-          id = @options[:namespace] + '_' + id if @options[:namespace]
+          id = input_name_from_type(type).gsub(/([\[\(])|(\]\[)/, "_").gsub(/[\]\)]/, "")
+          id = @options[:namespace] + "_" + id if @options[:namespace]
 
           id
         end
@@ -1079,7 +1091,7 @@ module ActionView
         # Given an ordering of datetime components, create the selection HTML
         # and join them with their appropriate separators.
         def build_selects_from_types(order)
-          select = ''
+          select = "".dup
           first_visible = order.find { |type| !@options[:"discard_#{type}"] }
           order.reverse_each do |type|
             separator = separator(type) unless type == first_visible # don't add before first visible field
@@ -1093,12 +1105,12 @@ module ActionView
           return "" if @options[:use_hidden]
 
           case type
-            when :year, :month, :day
-              @options[:"discard_#{type}"] ? "" : @options[:date_separator]
-            when :hour
-              (@options[:discard_year] && @options[:discard_day]) ? "" : @options[:datetime_separator]
-            when :minute, :second
-              @options[:"discard_#{type}"] ? "" : @options[:time_separator]
+          when :year, :month, :day
+            @options[:"discard_#{type}"] ? "" : @options[:date_separator]
+          when :hour
+            (@options[:discard_year] && @options[:discard_day]) ? "" : @options[:datetime_separator]
+          when :minute, :second
+            @options[:"discard_#{type}"] ? "" : @options[:time_separator]
           end
         end
     end
diff --git a/actionview/lib/action_view/helpers/debug_helper.rb b/actionview/lib/action_view/helpers/debug_helper.rb
index e9dccbad1c..52dff1f750 100644
--- a/actionview/lib/action_view/helpers/debug_helper.rb
+++ b/actionview/lib/action_view/helpers/debug_helper.rb
@@ -1,10 +1,11 @@
+# frozen_string_literal: true
+
 module ActionView
   # = Action View Debug Helper
   #
   # Provides a set of methods for making it easier to debug Rails objects.
-  module Helpers
+  module Helpers #:nodoc:
     module DebugHelper
-
       include TagHelper
 
       # Returns a YAML representation of +object+ wrapped with <pre> and </pre>.
@@ -25,10 +26,10 @@ module ActionView
       def debug(object)
         Marshal::dump(object)
         object = ERB::Util.html_escape(object.to_yaml)
-        content_tag(:pre, object, :class => "debug_dump")
+        content_tag(:pre, object, class: "debug_dump")
       rescue # errors from Marshal or YAML
         # Object couldn't be dumped, perhaps because of singleton methods -- this is the fallback
-        content_tag(:code, object.inspect, :class => "debug_dump")
+        content_tag(:code, object.inspect, class: "debug_dump")
       end
     end
   end
diff --git a/actionview/lib/action_view/helpers/form_helper.rb b/actionview/lib/action_view/helpers/form_helper.rb
index be5010cd9c..6185aa133f 100644
--- a/actionview/lib/action_view/helpers/form_helper.rb
+++ b/actionview/lib/action_view/helpers/form_helper.rb
@@ -1,18 +1,20 @@
-require 'cgi'
-require 'action_view/helpers/date_helper'
-require 'action_view/helpers/tag_helper'
-require 'action_view/helpers/form_tag_helper'
-require 'action_view/helpers/active_model_helper'
-require 'action_view/model_naming'
-require 'action_view/record_identifier'
-require 'active_support/core_ext/module/attribute_accessors'
-require 'active_support/core_ext/hash/slice'
-require 'active_support/core_ext/string/output_safety'
-require 'active_support/core_ext/string/inflections'
+# frozen_string_literal: true
+
+require "cgi"
+require "action_view/helpers/date_helper"
+require "action_view/helpers/tag_helper"
+require "action_view/helpers/form_tag_helper"
+require "action_view/helpers/active_model_helper"
+require "action_view/model_naming"
+require "action_view/record_identifier"
+require "active_support/core_ext/module/attribute_accessors"
+require "active_support/core_ext/hash/slice"
+require "active_support/core_ext/string/output_safety"
+require "active_support/core_ext/string/inflections"
 
 module ActionView
   # = Action View Form Helpers
-  module Helpers
+  module Helpers #:nodoc:
     # Form helpers are designed to make working with resources much easier
     # compared to using vanilla HTML.
     #
@@ -201,9 +203,9 @@ module ActionView
       #     <%= f.submit %>
       #   <% end %>
       #
-      # This also works for the methods in FormOptionHelper and DateHelper that
+      # This also works for the methods in FormOptionsHelper and DateHelper that
       # are designed to work with an object as base, like
-      # FormOptionHelper#collection_select and DateHelper#datetime_select.
+      # FormOptionsHelper#collection_select and DateHelper#datetime_select.
       #
       # === #form_for with a model object
       #
@@ -416,13 +418,13 @@ module ActionView
       #
       # To set an authenticity token you need to pass an <tt>:authenticity_token</tt> parameter
       #
-      #   <%= form_for @invoice, url: external_url, authenticity_token: 'external_token' do |f|
+      #   <%= form_for @invoice, url: external_url, authenticity_token: 'external_token' do |f| %>
       #     ...
       #   <% end %>
       #
       # If you don't want to an authenticity token field be rendered at all just pass <tt>false</tt>:
       #
-      #   <%= form_for @invoice, url: external_url, authenticity_token: false do |f|
+      #   <%= form_for @invoice, url: external_url, authenticity_token: false do |f| %>
       #     ...
       #   <% end %>
       def form_for(record, options = {}, &block)
@@ -467,13 +469,297 @@ module ActionView
         )
 
         options[:url] ||= if options.key?(:format)
-                            polymorphic_path(record, format: options.delete(:format))
-                          else
-                            polymorphic_path(record, {})
-                          end
+          polymorphic_path(record, format: options.delete(:format))
+        else
+          polymorphic_path(record, {})
+        end
       end
       private :apply_form_for_options!
 
+      mattr_accessor :form_with_generates_remote_forms, default: true
+
+      mattr_accessor :form_with_generates_ids, default: false
+
+      # Creates a form tag based on mixing URLs, scopes, or models.
+      #
+      #   # Using just a URL:
+      #   <%= form_with url: posts_path do |form| %>
+      #     <%= form.text_field :title %>
+      #   <% end %>
+      #   # =>
+      #   <form action="/posts" method="post" data-remote="true">
+      #     <input type="text" name="title">
+      #   </form>
+      #
+      #   # Adding a scope prefixes the input field names:
+      #   <%= form_with scope: :post, url: posts_path do |form| %>
+      #     <%= form.text_field :title %>
+      #   <% end %>
+      #   # =>
+      #   <form action="/posts" method="post" data-remote="true">
+      #     <input type="text" name="post[title]">
+      #   </form>
+      #
+      #   # Using a model infers both the URL and scope:
+      #   <%= form_with model: Post.new do |form| %>
+      #     <%= form.text_field :title %>
+      #   <% end %>
+      #   # =>
+      #   <form action="/posts" method="post" data-remote="true">
+      #     <input type="text" name="post[title]">
+      #   </form>
+      #
+      #   # An existing model makes an update form and fills out field values:
+      #   <%= form_with model: Post.first do |form| %>
+      #     <%= form.text_field :title %>
+      #   <% end %>
+      #   # =>
+      #   <form action="/posts/1" method="post" data-remote="true">
+      #     <input type="hidden" name="_method" value="patch">
+      #     <input type="text" name="post[title]" value="<the title of the post>">
+      #   </form>
+      #
+      #   # Though the fields don't have to correspond to model attributes:
+      #   <%= form_with model: Cat.new do |form| %>
+      #     <%= form.text_field :cats_dont_have_gills %>
+      #     <%= form.text_field :but_in_forms_they_can %>
+      #   <% end %>
+      #   # =>
+      #   <form action="/cats" method="post" data-remote="true">
+      #     <input type="text" name="cat[cats_dont_have_gills]">
+      #     <input type="text" name="cat[but_in_forms_they_can]">
+      #   </form>
+      #
+      # The parameters in the forms are accessible in controllers according to
+      # their name nesting. So inputs named +title+ and <tt>post[title]</tt> are
+      # accessible as <tt>params[:title]</tt> and <tt>params[:post][:title]</tt>
+      # respectively.
+      #
+      # By default +form_with+ attaches the <tt>data-remote</tt> attribute
+      # submitting the form via an XMLHTTPRequest in the background if an
+      # Unobtrusive JavaScript driver, like rails-ujs, is used. See the
+      # <tt>:local</tt> option for more.
+      #
+      # For ease of comparison the examples above left out the submit button,
+      # as well as the auto generated hidden fields that enable UTF-8 support
+      # and adds an authenticity token needed for cross site request forgery
+      # protection.
+      #
+      # === Resource-oriented style
+      #
+      # In many of the examples just shown, the +:model+ passed to +form_with+
+      # is a _resource_. It corresponds to a set of RESTful routes, most likely
+      # defined via +resources+ in <tt>config/routes.rb</tt>.
+      #
+      # So when passing such a model record, Rails infers the URL and method.
+      #
+      #   <%= form_with model: @post do |form| %>
+      #     ...
+      #   <% end %>
+      #
+      # is then equivalent to something like:
+      #
+      #   <%= form_with scope: :post, url: post_path(@post), method: :patch do |form| %>
+      #     ...
+      #   <% end %>
+      #
+      # And for a new record
+      #
+      #   <%= form_with model: Post.new do |form| %>
+      #     ...
+      #   <% end %>
+      #
+      # is equivalent to something like:
+      #
+      #   <%= form_with scope: :post, url: posts_path do |form| %>
+      #     ...
+      #   <% end %>
+      #
+      # ==== +form_with+ options
+      #
+      # * <tt>:url</tt> - The URL the form submits to. Akin to values passed to
+      #   +url_for+ or +link_to+. For example, you may use a named route
+      #   directly. When a <tt>:scope</tt> is passed without a <tt>:url</tt> the
+      #   form just submits to the current URL.
+      # * <tt>:method</tt> - The method to use when submitting the form, usually
+      #   either "get" or "post". If "patch", "put", "delete", or another verb
+      #   is used, a hidden input named <tt>_method</tt> is added to
+      #   simulate the verb over post.
+      # * <tt>:format</tt> - The format of the route the form submits to.
+      #   Useful when submitting to another resource type, like <tt>:json</tt>.
+      #   Skipped if a <tt>:url</tt> is passed.
+      # * <tt>:scope</tt> - The scope to prefix input field names with and
+      #   thereby how the submitted parameters are grouped in controllers.
+      # * <tt>:model</tt> - A model object to infer the <tt>:url</tt> and
+      #   <tt>:scope</tt> by, plus fill out input field values.
+      #   So if a +title+ attribute is set to "Ahoy!" then a +title+ input
+      #   field's value would be "Ahoy!".
+      #   If the model is a new record a create form is generated, if an
+      #   existing record, however, an update form is generated.
+      #   Pass <tt>:scope</tt> or <tt>:url</tt> to override the defaults.
+      #   E.g. turn <tt>params[:post]</tt> into <tt>params[:article]</tt>.
+      # * <tt>:authenticity_token</tt> - Authenticity token to use in the form.
+      #   Override with a custom authenticity token or pass <tt>false</tt> to
+      #   skip the authenticity token field altogether.
+      #   Useful when submitting to an external resource like a payment gateway
+      #   that might limit the valid fields.
+      #   Remote forms may omit the embedded authenticity token by setting
+      #   <tt>config.action_view.embed_authenticity_token_in_remote_forms = false</tt>.
+      #   This is helpful when fragment-caching the form. Remote forms
+      #   get the authenticity token from the <tt>meta</tt> tag, so embedding is
+      #   unnecessary unless you support browsers without JavaScript.
+      # * <tt>:local</tt> - By default form submits are remote and unobstrusive XHRs.
+      #   Disable remote submits with <tt>local: true</tt>.
+      # * <tt>:skip_enforcing_utf8</tt> - By default a hidden field named +utf8+
+      #   is output to enforce UTF-8 submits. Set to true to skip the field.
+      # * <tt>:builder</tt> - Override the object used to build the form.
+      # * <tt>:id</tt> - Optional HTML id attribute.
+      # * <tt>:class</tt> - Optional HTML class attribute.
+      # * <tt>:data</tt> - Optional HTML data attributes.
+      # * <tt>:html</tt> - Other optional HTML attributes for the form tag.
+      #
+      # === Examples
+      #
+      # When not passing a block, +form_with+ just generates an opening form tag.
+      #
+      #   <%= form_with(model: @post, url: super_posts_path) %>
+      #   <%= form_with(model: @post, scope: :article) %>
+      #   <%= form_with(model: @post, format: :json) %>
+      #   <%= form_with(model: @post, authenticity_token: false) %> # Disables the token.
+      #
+      # For namespaced routes, like +admin_post_url+:
+      #
+      #   <%= form_with(model: [ :admin, @post ]) do |form| %>
+      #     ...
+      #   <% end %>
+      #
+      # If your resource has associations defined, for example, you want to add comments
+      # to the document given that the routes are set correctly:
+      #
+      #   <%= form_with(model: [ @document, Comment.new ]) do |form| %>
+      #     ...
+      #   <% end %>
+      #
+      # Where <tt>@document = Document.find(params[:id])</tt>.
+      #
+      # === Mixing with other form helpers
+      #
+      # While +form_with+ uses a FormBuilder object it's possible to mix and
+      # match the stand-alone FormHelper methods and methods
+      # from FormTagHelper:
+      #
+      #   <%= form_with scope: :person do |form| %>
+      #     <%= form.text_field :first_name %>
+      #     <%= form.text_field :last_name %>
+      #
+      #     <%= text_area :person, :biography %>
+      #     <%= check_box_tag "person[admin]", "1", @person.company.admin? %>
+      #
+      #     <%= form.submit %>
+      #   <% end %>
+      #
+      # Same goes for the methods in FormOptionsHelper and DateHelper designed
+      # to work with an object as a base, like
+      # FormOptionsHelper#collection_select and DateHelper#datetime_select.
+      #
+      # === Setting the method
+      #
+      # You can force the form to use the full array of HTTP verbs by setting
+      #
+      #    method: (:get|:post|:patch|:put|:delete)
+      #
+      # in the options hash. If the verb is not GET or POST, which are natively
+      # supported by HTML forms, the form will be set to POST and a hidden input
+      # called _method will carry the intended verb for the server to interpret.
+      #
+      # === Setting HTML options
+      #
+      # You can set data attributes directly in a data hash, but HTML options
+      # besides id and class must be wrapped in an HTML key:
+      #
+      #   <%= form_with(model: @post, data: { behavior: "autosave" }, html: { name: "go" }) do |form| %>
+      #     ...
+      #   <% end %>
+      #
+      # generates
+      #
+      #   <form action="/posts/123" method="post" data-behavior="autosave" name="go">
+      #     <input name="_method" type="hidden" value="patch" />
+      #     ...
+      #   </form>
+      #
+      # === Removing hidden model id's
+      #
+      # The +form_with+ method automatically includes the model id as a hidden field in the form.
+      # This is used to maintain the correlation between the form data and its associated model.
+      # Some ORM systems do not use IDs on nested models so in this case you want to be able
+      # to disable the hidden id.
+      #
+      # In the following example the Post model has many Comments stored within it in a NoSQL database,
+      # thus there is no primary key for comments.
+      #
+      #   <%= form_with(model: @post) do |form| %>
+      #     <%= form.fields(:comments, skip_id: true) do |fields| %>
+      #       ...
+      #     <% end %>
+      #   <% end %>
+      #
+      # === Customized form builders
+      #
+      # You can also build forms using a customized FormBuilder class. Subclass
+      # FormBuilder and override or define some more helpers, then use your
+      # custom builder. For example, let's say you made a helper to
+      # automatically add labels to form inputs.
+      #
+      #   <%= form_with model: @person, url: { action: "create" }, builder: LabellingFormBuilder do |form| %>
+      #     <%= form.text_field :first_name %>
+      #     <%= form.text_field :last_name %>
+      #     <%= form.text_area :biography %>
+      #     <%= form.check_box :admin %>
+      #     <%= form.submit %>
+      #   <% end %>
+      #
+      # In this case, if you use:
+      #
+      #   <%= render form %>
+      #
+      # The rendered template is <tt>people/_labelling_form</tt> and the local
+      # variable referencing the form builder is called
+      # <tt>labelling_form</tt>.
+      #
+      # The custom FormBuilder class is automatically merged with the options
+      # of a nested +fields+ call, unless it's explicitly set.
+      #
+      # In many cases you will want to wrap the above in another helper, so you
+      # could do something like the following:
+      #
+      #   def labelled_form_with(**options, &block)
+      #     form_with(**options.merge(builder: LabellingFormBuilder), &block)
+      #   end
+      def form_with(model: nil, scope: nil, url: nil, format: nil, **options)
+        options[:allow_method_names_outside_object] = true
+        options[:skip_default_ids] = !form_with_generates_ids
+
+        if model
+          url ||= polymorphic_path(model, format: format)
+
+          model   = model.last if model.is_a?(Array)
+          scope ||= model_name_from_record_or_class(model).param_key
+        end
+
+        if block_given?
+          builder = instantiate_builder(scope, model, options)
+          output  = capture(builder, &Proc.new)
+          options[:multipart] ||= builder.multipart?
+
+          html_options = html_options_for_form_with(url, model, options)
+          form_tag_with_body(html_options, output)
+        else
+          html_options = html_options_for_form_with(url, model, options)
+          form_tag_html(html_options)
+        end
+      end
+
       # Creates a scope around a specific model object like form_for, but
       # doesn't create the form tags themselves. This makes fields_for suitable
       # for specifying additional model objects in the same form.
@@ -531,9 +817,9 @@ module ActionView
       # _class_ of the model object, e.g. if <tt>@person.permission</tt>, is
       # of class +Permission+, the field will still be named <tt>permission[admin]</tt>.
       #
-      # Note: This also works for the methods in FormOptionHelper and
+      # Note: This also works for the methods in FormOptionsHelper and
       # DateHelper that are designed to work with an object as base, like
-      # FormOptionHelper#collection_select and DateHelper#datetime_select.
+      # FormOptionsHelper#collection_select and DateHelper#datetime_select.
       #
       # === Nested Attributes Examples
       #
@@ -720,6 +1006,64 @@ module ActionView
         capture(builder, &block)
       end
 
+      # Scopes input fields with either an explicit scope or model.
+      # Like +form_with+ does with <tt>:scope</tt> or <tt>:model</tt>,
+      # except it doesn't output the form tags.
+      #
+      #   # Using a scope prefixes the input field names:
+      #   <%= fields :comment do |fields| %>
+      #     <%= fields.text_field :body %>
+      #   <% end %>
+      #   # => <input type="text" name="comment[body]>
+      #
+      #   # Using a model infers the scope and assigns field values:
+      #   <%= fields model: Comment.new(body: "full bodied") do |fields| %<
+      #     <%= fields.text_field :body %>
+      #   <% end %>
+      #   # =>
+      #   <input type="text" name="comment[body] value="full bodied">
+      #
+      #   # Using +fields+ with +form_with+:
+      #   <%= form_with model: @post do |form| %>
+      #     <%= form.text_field :title %>
+      #
+      #     <%= form.fields :comment do |fields| %>
+      #       <%= fields.text_field :body %>
+      #     <% end %>
+      #   <% end %>
+      #
+      # Much like +form_with+ a FormBuilder instance associated with the scope
+      # or model is yielded, so any generated field names are prefixed with
+      # either the passed scope or the scope inferred from the <tt>:model</tt>.
+      #
+      # === Mixing with other form helpers
+      #
+      # While +form_with+ uses a FormBuilder object it's possible to mix and
+      # match the stand-alone FormHelper methods and methods
+      # from FormTagHelper:
+      #
+      #   <%= fields model: @comment do |fields| %>
+      #     <%= fields.text_field :body %>
+      #
+      #     <%= text_area :commenter, :biography %>
+      #     <%= check_box_tag "comment[all_caps]", "1", @comment.commenter.hulk_mode? %>
+      #   <% end %>
+      #
+      # Same goes for the methods in FormOptionsHelper and DateHelper designed
+      # to work with an object as a base, like
+      # FormOptionsHelper#collection_select and DateHelper#datetime_select.
+      def fields(scope = nil, model: nil, **options, &block)
+        options[:allow_method_names_outside_object] = true
+        options[:skip_default_ids] = !form_with_generates_ids
+
+        if model
+          scope ||= model_name_from_record_or_class(model).param_key
+        end
+
+        builder = instantiate_builder(scope, model, options)
+        capture(builder, &block)
+      end
+
       # Returns a label tag tailored for labelling an input field for a specified attribute (identified by +method+) on an object
       # assigned to the template (identified by +object+). The text of label will default to the attribute name unless a translation
       # is found in the current I18n locale (through helpers.label.<modelname>.<attribute>) or you specify it explicitly.
@@ -860,26 +1204,8 @@ module ActionView
       #
       #   file_field(:attachment, :file, class: 'file_input')
       #   # => <input type="file" id="attachment_file" name="attachment[file]" class="file_input" />
-      #
-      # ==== Gotcha
-      #
-      # The HTML specification says that when a file field is empty, web browsers
-      # do not send any value to the server. Unfortunately this introduces a
-      # gotcha: if a +User+ model has an +avatar+ field, and no file is selected,
-      # then the +avatar+ parameter is empty. Thus, any mass-assignment idiom like
-      #
-      #   @user.update(params[:user])
-      #
-      # wouldn't update the +avatar+ field.
-      #
-      # To prevent this, the helper generates an auxiliary hidden field before
-      # every file field. The hidden field has the same name as the file one and
-      # a blank value.
-      #
-      # In case you don't want the helper to generate this hidden field you can
-      # specify the <tt>include_hidden: false</tt> option.
       def file_field(object_name, method, options = {})
-        Tags::FileField.new(object_name, method, self, options).render
+        Tags::FileField.new(object_name, method, self, convert_direct_upload_option_to_url(options.dup)).render
       end
 
       # Returns a textarea opening and closing tag set tailored for accessing a specified attribute (identified by +method+)
@@ -983,6 +1309,7 @@ module ActionView
       #   # => <input type="radio" id="post_category_rails" name="post[category]" value="rails" checked="checked" />
       #   #    <input type="radio" id="post_category_java" name="post[category]" value="java" />
       #
+      #   # Let's say that @user.receive_newsletter returns "no":
       #   radio_button("user", "receive_newsletter", "yes")
       #   radio_button("user", "receive_newsletter", "no")
       #   # => <input type="radio" id="user_receive_newsletter_yes" name="user[receive_newsletter]" value="yes" />
@@ -1092,42 +1419,9 @@ module ActionView
         Tags::TimeField.new(object_name, method, self, options).render
       end
 
-      # Returns a text_field of type "datetime".
-      #
-      #   datetime_field("user", "born_on")
-      #   # => <input id="user_born_on" name="user[born_on]" type="datetime" />
-      #
-      # The default value is generated by trying to call +strftime+ with "%Y-%m-%dT%T.%L%z"
-      # on the object's value, which makes it behave as expected for instances
-      # of DateTime and ActiveSupport::TimeWithZone.
-      #
-      #   @user.born_on = Date.new(1984, 1, 12)
-      #   datetime_field("user", "born_on")
-      #   # => <input id="user_born_on" name="user[born_on]" type="datetime" value="1984-01-12T00:00:00.000+0000" />
-      #
-      # You can create values for the "min" and "max" attributes by passing
-      # instances of Date or Time to the options hash.
-      #
-      #   datetime_field("user", "born_on", min: Date.today)
-      #   # => <input id="user_born_on" name="user[born_on]" type="datetime" min="2014-05-20T00:00:00.000+0000" />
-      #
-      # Alternatively, you can pass a String formatted as an ISO8601 datetime
-      # with UTC offset as the values for "min" and "max."
-      #
-      #   datetime_field("user", "born_on", min: "2014-05-20T00:00:00+0000")
-      #   # => <input id="user_born_on" name="user[born_on]" type="datetime" min="2014-05-20T00:00:00.000+0000" />
-      #
-      def datetime_field(object_name, method, options = {})
-        ActiveSupport::Deprecation.warn(<<-MESSAGE.squish)
-          datetime_field is deprecated and will be removed in Rails 5.1.
-          Use datetime_local_field instead.
-        MESSAGE
-        Tags::DatetimeField.new(object_name, method, self, options).render
-      end
-
       # Returns a text_field of type "datetime-local".
       #
-      #   datetime_local_field("user", "born_on")
+      #   datetime_field("user", "born_on")
       #   # => <input id="user_born_on" name="user[born_on]" type="datetime-local" />
       #
       # The default value is generated by trying to call +strftime+ with "%Y-%m-%dT%T"
@@ -1135,25 +1429,27 @@ module ActionView
       # of DateTime and ActiveSupport::TimeWithZone.
       #
       #   @user.born_on = Date.new(1984, 1, 12)
-      #   datetime_local_field("user", "born_on")
+      #   datetime_field("user", "born_on")
       #   # => <input id="user_born_on" name="user[born_on]" type="datetime-local" value="1984-01-12T00:00:00" />
       #
       # You can create values for the "min" and "max" attributes by passing
       # instances of Date or Time to the options hash.
       #
-      #   datetime_local_field("user", "born_on", min: Date.today)
+      #   datetime_field("user", "born_on", min: Date.today)
       #   # => <input id="user_born_on" name="user[born_on]" type="datetime-local" min="2014-05-20T00:00:00.000" />
       #
       # Alternatively, you can pass a String formatted as an ISO8601 datetime as
       # the values for "min" and "max."
       #
-      #   datetime_local_field("user", "born_on", min: "2014-05-20T00:00:00")
+      #   datetime_field("user", "born_on", min: "2014-05-20T00:00:00")
       #   # => <input id="user_born_on" name="user[born_on]" type="datetime-local" min="2014-05-20T00:00:00.000" />
       #
-      def datetime_local_field(object_name, method, options = {})
+      def datetime_field(object_name, method, options = {})
         Tags::DatetimeLocalField.new(object_name, method, self, options).render
       end
 
+      alias datetime_local_field datetime_field
+
       # Returns a text_field of type "month".
       #
       #   month_field("user", "born_on")
@@ -1223,6 +1519,34 @@ module ActionView
       end
 
       private
+        def html_options_for_form_with(url_for_options = nil, model = nil, html: {}, local: !form_with_generates_remote_forms,
+          skip_enforcing_utf8: false, **options)
+          html_options = options.slice(:id, :class, :multipart, :method, :data).merge(html)
+          html_options[:method] ||= :patch if model.respond_to?(:persisted?) && model.persisted?
+          html_options[:enforce_utf8] = !skip_enforcing_utf8
+
+          html_options[:enctype] = "multipart/form-data" if html_options.delete(:multipart)
+
+          # The following URL is unescaped, this is just a hash of options, and it is the
+          # responsibility of the caller to escape all the values.
+          html_options[:action] = url_for(url_for_options || {})
+          html_options[:"accept-charset"] = "UTF-8"
+          html_options[:"data-remote"] = true unless local
+
+          html_options[:authenticity_token] = options.delete(:authenticity_token)
+
+          if !local && html_options[:authenticity_token].blank?
+            html_options[:authenticity_token] = embed_authenticity_token_in_remote_forms
+          end
+
+          if html_options[:authenticity_token] == true
+            # Include the default authenticity_token, which is only generated when it's set to nil,
+            # but we needed the true value to override the default of no authenticity_token on data-remote.
+            html_options[:authenticity_token] = nil
+          end
+
+          html_options.stringify_keys!
+        end
 
         def instantiate_builder(record_name, record_object, options)
           case record_name
@@ -1231,7 +1555,7 @@ module ActionView
             object_name = record_name
           else
             object = record_name
-            object_name = model_name_from_record_or_class(object).param_key
+            object_name = model_name_from_record_or_class(object).param_key if object
           end
 
           builder = options[:builder] || default_form_builder_class
@@ -1257,7 +1581,7 @@ module ActionView
     # In the above block, a +FormBuilder+ object is yielded as the
     # +person_form+ variable. This allows you to generate the +text_field+
     # and +check_box+ fields by specifying their eponymous methods, which
-    # modify the underlying template and associates the +@person+ model object
+    # modify the underlying template and associates the <tt>@person</tt> model object
     # with the form.
     #
     # The +FormBuilder+ object can be thought of as serving as a proxy for the
@@ -1296,14 +1620,15 @@ module ActionView
       include ModelNaming
 
       # The methods which wrap a form helper call.
-      class_attribute :field_helpers
-      self.field_helpers = [:fields_for, :label, :text_field, :password_field,
-                            :hidden_field, :file_field, :text_area, :check_box,
-                            :radio_button, :color_field, :search_field,
-                            :telephone_field, :phone_field, :date_field,
-                            :time_field, :datetime_field, :datetime_local_field,
-                            :month_field, :week_field, :url_field, :email_field,
-                            :number_field, :range_field]
+      class_attribute :field_helpers, default: [
+        :fields_for, :fields, :label, :text_field, :password_field,
+        :hidden_field, :file_field, :text_area, :check_box,
+        :radio_button, :color_field, :search_field,
+        :telephone_field, :phone_field, :date_field,
+        :time_field, :datetime_field, :datetime_local_field,
+        :month_field, :week_field, :url_field, :email_field,
+        :number_field, :range_field
+      ]
 
       attr_accessor :object_name, :object, :options
 
@@ -1319,7 +1644,7 @@ module ActionView
       end
 
       def self._to_partial_path
-        @_to_partial_path ||= name.demodulize.underscore.sub!(/_builder$/, '')
+        @_to_partial_path ||= name.demodulize.underscore.sub!(/_builder$/, "")
       end
 
       def to_partial_path
@@ -1333,19 +1658,23 @@ module ActionView
       def initialize(object_name, object, template, options)
         @nested_child_index = {}
         @object_name, @object, @template, @options = object_name, object, template, options
-        @default_options = @options ? @options.slice(:index, :namespace) : {}
+        @default_options = @options ? @options.slice(:index, :namespace, :skip_default_ids, :allow_method_names_outside_object) : {}
+
+        convert_to_legacy_options(@options)
+
         if @object_name.to_s.match(/\[\]$/)
-          if object ||= @template.instance_variable_get("@#{Regexp.last_match.pre_match}") and object.respond_to?(:to_param)
+          if (object ||= @template.instance_variable_get("@#{Regexp.last_match.pre_match}")) && object.respond_to?(:to_param)
             @auto_index = object.to_param
           else
             raise ArgumentError, "object[] naming but object param and @object var don't exist or don't respond to to_param: #{object.inspect}"
           end
         end
+
         @multipart = nil
         @index = options[:index] || options[:child_index]
       end
 
-      (field_helpers - [:label, :check_box, :radio_button, :fields_for, :hidden_field, :file_field]).each do |selector|
+      (field_helpers - [:label, :check_box, :radio_button, :fields_for, :fields, :hidden_field, :file_field]).each do |selector|
         class_eval <<-RUBY_EVAL, __FILE__, __LINE__ + 1
           def #{selector}(method, options = {})  # def text_field(method, options = {})
             @template.send(                      #   @template.send(
@@ -1414,9 +1743,9 @@ module ActionView
       # _class_ of the model object, e.g. if <tt>@person.permission</tt>, is
       # of class +Permission+, the field will still be named <tt>permission[admin]</tt>.
       #
-      # Note: This also works for the methods in FormOptionHelper and
+      # Note: This also works for the methods in FormOptionsHelper and
       # DateHelper that are designed to work with an object as base, like
-      # FormOptionHelper#collection_select and DateHelper#datetime_select.
+      # FormOptionsHelper#collection_select and DateHelper#datetime_select.
       #
       # === Nested Attributes Examples
       #
@@ -1614,26 +1943,37 @@ module ActionView
           record_name   = model_name_from_record_or_class(record_object).param_key
         end
 
+        object_name = @object_name
         index = if options.has_key?(:index)
           options[:index]
         elsif defined?(@auto_index)
-          self.object_name = @object_name.to_s.sub(/\[\]$/,"")
+          object_name = object_name.to_s.sub(/\[\]$/, "")
           @auto_index
         end
 
         record_name = if index
-                        "#{object_name}[#{index}][#{record_name}]"
-                      elsif record_name.to_s.end_with?('[]')
-                        record_name = record_name.to_s.sub(/(.*)\[\]$/, "[\\1][#{record_object.id}]")
-                        "#{object_name}#{record_name}"
-                      else
-                        "#{object_name}[#{record_name}]"
-                      end
+          "#{object_name}[#{index}][#{record_name}]"
+        elsif record_name.to_s.end_with?("[]")
+          record_name = record_name.to_s.sub(/(.*)\[\]$/, "[\\1][#{record_object.id}]")
+          "#{object_name}#{record_name}"
+        else
+          "#{object_name}[#{record_name}]"
+        end
         fields_options[:child_index] = index
 
         @template.fields_for(record_name, record_object, fields_options, &block)
       end
 
+      # See the docs for the <tt>ActionView::FormHelper.fields</tt> helper method.
+      def fields(scope = nil, model: nil, **options, &block)
+        options[:allow_method_names_outside_object] = true
+        options[:skip_default_ids] = !FormHelper.form_with_generates_ids
+
+        convert_to_legacy_options(options)
+
+        fields_for(scope || model, model, **options, &block)
+      end
+
       # Returns a label tag tailored for labelling an input field for a specified attribute (identified by +method+) on an object
       # assigned to the template (identified by +object+). The text of label will default to the attribute name unless a translation
       # is found in the current I18n locale (through helpers.label.<modelname>.<attribute>) or you specify it explicitly.
@@ -1760,7 +2100,7 @@ module ActionView
       #   # => <input type="radio" id="post_category_rails" name="post[category]" value="rails" checked="checked" />
       #   #    <input type="radio" id="post_category_java" name="post[category]" value="java" />
       #
-      #   # Let's say that @user.category returns "no":
+      #   # Let's say that @user.receive_newsletter returns "no":
       #   radio_button("receive_newsletter", "yes")
       #   radio_button("receive_newsletter", "no")
       #   # => <input type="radio" id="user_receive_newsletter_yes" name="user[receive_newsletter]" value="yes" />
@@ -1837,11 +2177,11 @@ module ActionView
       #     <%= f.submit %>
       #   <% end %>
       #
-      # In the example above, if @post is a new record, it will use "Create Post" as
-      # submit button label, otherwise, it uses "Update Post".
+      # In the example above, if <tt>@post</tt> is a new record, it will use "Create Post" as
+      # submit button label; otherwise, it uses "Update Post".
       #
-      # Those labels can be customized using I18n, under the helpers.submit key and accept
-      # the %{model} as translation interpolation:
+      # Those labels can be customized using I18n under the +helpers.submit+ key and using
+      # <tt>%{model}</tt> for translation interpolation:
       #
       #   en:
       #     helpers:
@@ -1849,7 +2189,7 @@ module ActionView
       #         create: "Create a %{model}"
       #         update: "Confirm changes to %{model}"
       #
-      # It also searches for a key specific for the given object:
+      # It also searches for a key specific to the given object:
       #
       #   en:
       #     helpers:
@@ -1857,7 +2197,7 @@ module ActionView
       #         post:
       #           create: "Add %{model}"
       #
-      def submit(value=nil, options={})
+      def submit(value = nil, options = {})
         value, options = nil, value if value.is_a?(Hash)
         value ||= submit_default_value
         @template.submit_tag(value, options)
@@ -1870,11 +2210,11 @@ module ActionView
       #     <%= f.button %>
       #   <% end %>
       #
-      # In the example above, if @post is a new record, it will use "Create Post" as
-      # button label, otherwise, it uses "Update Post".
+      # In the example above, if <tt>@post</tt> is a new record, it will use "Create Post" as
+      # button label; otherwise, it uses "Update Post".
       #
-      # Those labels can be customized using I18n, under the helpers.submit key
-      # (the same as submit helper) and accept the %{model} as translation interpolation:
+      # Those labels can be customized using I18n under the +helpers.submit+ key
+      # (the same as submit helper) and using <tt>%{model}</tt> for translation interpolation:
       #
       #   en:
       #     helpers:
@@ -1882,7 +2222,7 @@ module ActionView
       #         create: "Create a %{model}"
       #         update: "Confirm changes to %{model}"
       #
-      # It also searches for a key specific for the given object:
+      # It also searches for a key specific to the given object:
       #
       #   en:
       #     helpers:
@@ -1982,12 +2322,16 @@ module ActionView
           @nested_child_index[name] ||= -1
           @nested_child_index[name] += 1
         end
+
+        def convert_to_legacy_options(options)
+          if options.key?(:skip_id)
+            options[:include_id] = !options.delete(:skip_id)
+          end
+        end
     end
   end
 
   ActiveSupport.on_load(:action_view) do
-    cattr_accessor(:default_form_builder, instance_writer: false, instance_reader: false) do
-      ::ActionView::Helpers::FormBuilder
-    end
+    cattr_accessor :default_form_builder, instance_writer: false, instance_reader: false, default: ::ActionView::Helpers::FormBuilder
   end
 end
diff --git a/actionview/lib/action_view/helpers/form_options_helper.rb b/actionview/lib/action_view/helpers/form_options_helper.rb
index b277efd7b6..fe5e0b693e 100644
--- a/actionview/lib/action_view/helpers/form_options_helper.rb
+++ b/actionview/lib/action_view/helpers/form_options_helper.rb
@@ -1,13 +1,15 @@
-require 'cgi'
-require 'erb'
-require 'action_view/helpers/form_helper'
-require 'active_support/core_ext/string/output_safety'
-require 'active_support/core_ext/array/extract_options'
-require 'active_support/core_ext/array/wrap'
+# frozen_string_literal: true
+
+require "cgi"
+require "erb"
+require "action_view/helpers/form_helper"
+require "active_support/core_ext/string/output_safety"
+require "active_support/core_ext/array/extract_options"
+require "active_support/core_ext/array/wrap"
 
 module ActionView
   # = Action View Form Option Helpers
-  module Helpers
+  module Helpers #:nodoc:
     # Provides a number of methods for turning different kinds of containers into a set of option tags.
     #
     # The <tt>collection_select</tt>, <tt>select</tt> and <tt>time_zone_select</tt> methods take an <tt>options</tt> parameter, a hash:
@@ -212,9 +214,13 @@ module ActionView
       # * +method+ - The attribute of +object+ corresponding to the select tag
       # * +collection+ - An array of objects representing the <tt><optgroup></tt> tags.
       # * +group_method+ - The name of a method which, when called on a member of +collection+, returns an
-      #   array of child objects representing the <tt><option></tt> tags.
+      #   array of child objects representing the <tt><option></tt> tags. It can also be any object that responds
+      #   to +call+, such as a +proc+, that will be called for each member of the +collection+ to retrieve the
+      #   value.
       # * +group_label_method+ - The name of a method which, when called on a member of +collection+, returns a
-      #   string to be used as the +label+ attribute for its <tt><optgroup></tt> tag.
+      #   string to be used as the +label+ attribute for its <tt><optgroup></tt> tag. It can also be any object
+      #   that responds to +call+, such as a +proc+, that will be called for each member of the +collection+ to
+      #   retrieve the label.
       # * +option_key_method+ - The name of a method which, when called on a child object of a member of
       #   +collection+, returns a value to be used as the +value+ attribute for its <tt><option></tt> tag.
       # * +option_value_method+ - The name of a method which, when called on a child object of a member of
@@ -277,17 +283,17 @@ module ActionView
       # Finally, this method supports a <tt>:default</tt> option, which selects
       # a default ActiveSupport::TimeZone if the object's time zone is +nil+.
       #
-      #   time_zone_select( "user", "time_zone", nil, include_blank: true)
+      #   time_zone_select("user", "time_zone", nil, include_blank: true)
       #
-      #   time_zone_select( "user", "time_zone", nil, default: "Pacific Time (US & Canada)" )
+      #   time_zone_select("user", "time_zone", nil, default: "Pacific Time (US & Canada)")
       #
-      #   time_zone_select( "user", 'time_zone', ActiveSupport::TimeZone.us_zones, default: "Pacific Time (US & Canada)")
+      #   time_zone_select("user", 'time_zone', ActiveSupport::TimeZone.us_zones, default: "Pacific Time (US & Canada)")
       #
-      #   time_zone_select( "user", 'time_zone', [ ActiveSupport::TimeZone['Alaska'], ActiveSupport::TimeZone['Hawaii'] ])
+      #   time_zone_select("user", 'time_zone', [ ActiveSupport::TimeZone['Alaska'], ActiveSupport::TimeZone['Hawaii'] ])
       #
-      #   time_zone_select( "user", 'time_zone', /Australia/)
+      #   time_zone_select("user", 'time_zone', /Australia/)
       #
-      #   time_zone_select( "user", "time_zone", ActiveSupport::TimeZone.all.sort, model: ActiveSupport::TimeZone)
+      #   time_zone_select("user", "time_zone", ActiveSupport::TimeZone.all.sort, model: ActiveSupport::TimeZone)
       def time_zone_select(object, method, priority_zones = nil, options = {}, html_options = {})
         Tags::TimeZoneSelect.new(object, method, self, priority_zones, options, html_options).render
       end
@@ -363,7 +369,7 @@ module ActionView
           html_attributes[:disabled] ||= disabled && option_value_selected?(value, disabled)
           html_attributes[:value] = value
 
-          content_tag_string(:option, text, html_attributes)
+          tag_builder.content_tag_string(:option, text, html_attributes)
         end.join("\n").html_safe
       end
 
@@ -455,9 +461,9 @@ module ActionView
       def option_groups_from_collection_for_select(collection, group_method, group_label_method, option_key_method, option_value_method, selected_key = nil)
         collection.map do |group|
           option_tags = options_from_collection_for_select(
-            group.send(group_method), option_key_method, option_value_method, selected_key)
+            value_for_collection(group, group_method), option_key_method, option_value_method, selected_key)
 
-          content_tag("optgroup".freeze, option_tags, label: group.send(group_label_method))
+          content_tag("optgroup".freeze, option_tags, label: value_for_collection(group, group_label_method))
         end.join.html_safe
       end
 
@@ -578,7 +584,7 @@ module ActionView
           end
 
           zone_options.safe_concat options_for_select(convert_zones[priority_zones], selected)
-          zone_options.safe_concat content_tag("option".freeze, '-------------', value: '', disabled: true)
+          zone_options.safe_concat content_tag("option".freeze, "-------------", value: "", disabled: true)
           zone_options.safe_concat "\n"
 
           zones = zones - priority_zones
@@ -651,12 +657,12 @@ module ActionView
       # The HTML specification says when nothing is select on a collection of radio buttons
       # web browsers do not send any value to server.
       # Unfortunately this introduces a gotcha:
-      # if a +User+ model has a +category_id+ field, and in the form none category is selected no +category_id+ parameter is sent. So,
-      # any strong parameters idiom like
+      # if a +User+ model has a +category_id+ field and in the form no category is selected, no +category_id+ parameter is sent. So,
+      # any strong parameters idiom like:
       #
       #   params.require(:user).permit(...)
       #
-      # will raise an error since no +{user: ...}+ will be present.
+      # will raise an error since no <tt>{user: ...}</tt> will be present.
       #
       # To prevent this the helper generates an auxiliary hidden field before
       # every collection of radio buttons. The hidden field has the same name as collection radio button and blank value.
@@ -800,7 +806,7 @@ module ActionView
         end
 
         def prompt_text(prompt)
-          prompt.kind_of?(String) ? prompt : I18n.translate('helpers.select.prompt', default: 'Please select')
+          prompt.kind_of?(String) ? prompt : I18n.translate("helpers.select.prompt", default: "Please select")
         end
     end
 
diff --git a/actionview/lib/action_view/helpers/form_tag_helper.rb b/actionview/lib/action_view/helpers/form_tag_helper.rb
index 82f2fd30c7..e86e18dd78 100644
--- a/actionview/lib/action_view/helpers/form_tag_helper.rb
+++ b/actionview/lib/action_view/helpers/form_tag_helper.rb
@@ -1,11 +1,13 @@
-require 'cgi'
-require 'action_view/helpers/tag_helper'
-require 'active_support/core_ext/string/output_safety'
-require 'active_support/core_ext/module/attribute_accessors'
+# frozen_string_literal: true
+
+require "cgi"
+require "action_view/helpers/tag_helper"
+require "active_support/core_ext/string/output_safety"
+require "active_support/core_ext/module/attribute_accessors"
 
 module ActionView
   # = Action View Form Tag Helpers
-  module Helpers
+  module Helpers #:nodoc:
     # Provides a number of methods for creating form tags that don't rely on an Active Record object assigned to the template like
     # FormHelper does. Instead, you provide the names and values manually.
     #
@@ -18,7 +20,7 @@ module ActionView
       include TextHelper
 
       mattr_accessor :embed_authenticity_token_in_remote_forms
-      self.embed_authenticity_token_in_remote_forms = false
+      self.embed_authenticity_token_in_remote_forms = nil
 
       # Starts a form tag that points the action to a url configured with <tt>url_for_options</tt> just like
       # ActionController::Base#url_for. The method for the form defaults to POST.
@@ -113,7 +115,7 @@ module ActionView
       #   #    <option>Write</option></select>
       #
       #   select_tag "people", options_from_collection_for_select(@people, "id", "name"), include_blank: true
-      #   # => <select id="people" name="people"><option value=""></option><option value="1">David</option></select>
+      #   # => <select id="people" name="people"><option value="" label=" "></option><option value="1">David</option></select>
       #
       #   select_tag "people", options_from_collection_for_select(@people, "id", "name"), include_blank: "All"
       #   # => <select id="people" name="people"><option value="">All</option><option value="1">David</option></select>
@@ -134,11 +136,11 @@ module ActionView
 
         if options.include?(:include_blank)
           include_blank = options.delete(:include_blank)
-          options_for_blank_options_tag = { value: '' }
+          options_for_blank_options_tag = { value: "" }
 
           if include_blank == true
-            include_blank = ''
-            options_for_blank_options_tag[:label] = ' '
+            include_blank = ""
+            options_for_blank_options_tag[:label] = " "
           end
 
           if include_blank
@@ -147,7 +149,7 @@ module ActionView
         end
 
         if prompt = options.delete(:prompt)
-          option_tags = content_tag("option".freeze, prompt, value: '').safe_concat(option_tags)
+          option_tags = content_tag("option".freeze, prompt, value: "").safe_concat(option_tags)
         end
 
         content_tag "select".freeze, option_tags, { "name" => html_name, "id" => sanitize_to_id(name) }.update(options.stringify_keys)
@@ -272,7 +274,7 @@ module ActionView
       #   file_field_tag 'file', accept: 'text/html', class: 'upload', value: 'index.html'
       #   # => <input accept="text/html" class="upload" id="file" name="file" type="file" value="index.html" />
       def file_field_tag(name, options = {})
-        text_field_tag(name, nil, options.merge(type: :file))
+        text_field_tag(name, nil, convert_direct_upload_option_to_url(options.merge(type: :file)))
       end
 
       # Creates a password field, a masked text field that will hide the users input behind a mask character.
@@ -392,7 +394,7 @@ module ActionView
       #   # => <input checked="checked" id="receive_updates_no" name="receive_updates" type="radio" value="no" />
       #
       #   radio_button_tag 'time_slot', "3:00 p.m.", false, disabled: true
-      #   # => <input disabled="disabled" id="time_slot_300_pm" name="time_slot" type="radio" value="3:00 p.m." />
+      #   # => <input disabled="disabled" id="time_slot_3:00_p.m." name="time_slot" type="radio" value="3:00 p.m." />
       #
       #   radio_button_tag 'color', "green", true, class: "color_input"
       #   # => <input checked="checked" class="color_input" id="color_green" name="color" type="radio" value="green" />
@@ -442,31 +444,19 @@ module ActionView
       #   # => <input name='commit' type='submit' value='Save' data-disable-with="Save" data-confirm="Are you sure?" />
       #
       def submit_tag(value = "Save changes", options = {})
-        options = options.stringify_keys
+        options = options.deep_stringify_keys
         tag_options = { "type" => "submit", "name" => "commit", "value" => value }.update(options)
-
-        if ActionView::Base.automatically_disable_submit_tag
-          unless tag_options["data-disable-with"] == false || (tag_options["data"] && tag_options["data"][:disable_with] == false)
-            disable_with_text = tag_options["data-disable-with"]
-            disable_with_text ||= tag_options["data"][:disable_with] if tag_options["data"]
-            disable_with_text ||= value.to_s.clone
-            tag_options.deep_merge!("data" => { "disable_with" => disable_with_text })
-          else
-            tag_options["data"].delete(:disable_with) if tag_options["data"]
-          end
-          tag_options.delete("data-disable-with")
-        end
-
+        set_default_disable_with value, tag_options
         tag :input, tag_options
       end
 
       # Creates a button element that defines a <tt>submit</tt> button,
-      # <tt>reset</tt>button or a generic button which can be used in
+      # <tt>reset</tt> button or a generic button which can be used in
       # JavaScript, for example. You can use the button tag as a regular
       # submit tag but it isn't supported in legacy browsers. However,
       # the button tag does allow for richer labels such as images and emphasis,
       # so this helper will also accept a block. By default, it will create
-      # a button tag with type `submit`, if type is not given.
+      # a button tag with type <tt>submit</tt>, if type is not given.
       #
       # ==== Options
       # * <tt>:data</tt> - This option can be used to add custom data attributes.
@@ -518,12 +508,12 @@ module ActionView
           options ||= {}
         end
 
-        options = { 'name' => 'button', 'type' => 'submit' }.merge!(options.stringify_keys)
+        options = { "name" => "button", "type" => "submit" }.merge!(options.stringify_keys)
 
         if block_given?
           content_tag :button, options, &block
         else
-          content_tag :button, content_or_options || 'Button', options
+          content_tag :button, content_or_options || "Button", options
         end
       end
 
@@ -544,22 +534,22 @@ module ActionView
       #
       # ==== Examples
       #   image_submit_tag("login.png")
-      #   # => <input alt="Login" src="/assets/login.png" type="image" />
+      #   # => <input src="/assets/login.png" type="image" />
       #
       #   image_submit_tag("purchase.png", disabled: true)
-      #   # => <input alt="Purchase" disabled="disabled" src="/assets/purchase.png" type="image" />
+      #   # => <input disabled="disabled" src="/assets/purchase.png" type="image" />
       #
       #   image_submit_tag("search.png", class: 'search_button', alt: 'Find')
-      #   # => <input alt="Find" class="search_button" src="/assets/search.png" type="image" />
+      #   # => <input class="search_button" src="/assets/search.png" type="image" />
       #
       #   image_submit_tag("agree.png", disabled: true, class: "agree_disagree_button")
-      #   # => <input alt="Agree" class="agree_disagree_button" disabled="disabled" src="/assets/agree.png" type="image" />
+      #   # => <input class="agree_disagree_button" disabled="disabled" src="/assets/agree.png" type="image" />
       #
       #   image_submit_tag("save.png", data: { confirm: "Are you sure?" })
-      #   # => <input alt="Save" src="/assets/save.png" data-confirm="Are you sure?" type="image" />
+      #   # => <input src="/assets/save.png" data-confirm="Are you sure?" type="image" />
       def image_submit_tag(source, options = {})
         options = options.stringify_keys
-        tag :input, { "alt" => image_alt(source), "type" => "image", "src" => path_to_image(source) }.update(options)
+        tag :input, { "type" => "image", "src" => path_to_image(source) }.update(options)
       end
 
       # Creates a field set for grouping HTML form elements.
@@ -685,7 +675,7 @@ module ActionView
         text_field_tag(name, value, options.merge(type: :time))
       end
 
-      # Creates a text field of type "datetime".
+      # Creates a text field of type "datetime-local".
       #
       # === Options
       # * <tt>:min</tt> - The minimum acceptable value.
@@ -693,23 +683,10 @@ module ActionView
       # * <tt>:step</tt> - The acceptable value granularity.
       # * Otherwise accepts the same options as text_field_tag.
       def datetime_field_tag(name, value = nil, options = {})
-        ActiveSupport::Deprecation.warn(<<-MESSAGE.squish)
-          datetime_field_tag is deprecated and will be removed in Rails 5.1.
-          Use datetime_local_field_tag instead.
-        MESSAGE
-        text_field_tag(name, value, options.merge(type: :datetime))
+        text_field_tag(name, value, options.merge(type: "datetime-local"))
       end
 
-      # Creates a text field of type "datetime-local".
-      #
-      # === Options
-      # * <tt>:min</tt> - The minimum acceptable value.
-      # * <tt>:max</tt> - The maximum acceptable value.
-      # * <tt>:step</tt> - The acceptable value granularity.
-      # * Otherwise accepts the same options as text_field_tag.
-      def datetime_local_field_tag(name, value = nil, options = {})
-        text_field_tag(name, value, options.merge(type: 'datetime-local'))
-      end
+      alias datetime_local_field_tag datetime_field_tag
 
       # Creates a text field of type "month".
       #
@@ -870,11 +847,12 @@ module ActionView
           authenticity_token = html_options.delete("authenticity_token")
           method = html_options.delete("method").to_s.downcase
 
-          method_tag = case method
-            when 'get'
+          method_tag = \
+            case method
+            when "get"
               html_options["method"] = "get"
-              ''
-            when 'post', ''
+              ""
+            when "post", ""
               html_options["method"] = "post"
               token_tag(authenticity_token, form_options: {
                 action: html_options["action"],
@@ -886,7 +864,7 @@ module ActionView
                 action: html_options["action"],
                 method: method
               })
-          end
+            end
 
           if html_options.delete("enforce_utf8") { true }
             utf8_enforcer_tag + method_tag
@@ -908,7 +886,30 @@ module ActionView
 
         # see http://www.w3.org/TR/html4/types.html#type-name
         def sanitize_to_id(name)
-          name.to_s.delete(']').tr('^-a-zA-Z0-9:.', "_")
+          name.to_s.delete("]").tr("^-a-zA-Z0-9:.", "_")
+        end
+
+        def set_default_disable_with(value, tag_options)
+          return unless ActionView::Base.automatically_disable_submit_tag
+          data = tag_options["data"]
+
+          unless tag_options["data-disable-with"] == false || (data && data["disable_with"] == false)
+            disable_with_text = tag_options["data-disable-with"]
+            disable_with_text ||= data["disable_with"] if data
+            disable_with_text ||= value.to_s.clone
+            tag_options.deep_merge!("data" => { "disable_with" => disable_with_text })
+          else
+            data.delete("disable_with") if data
+          end
+
+          tag_options.delete("data-disable-with")
+        end
+
+        def convert_direct_upload_option_to_url(options)
+          if options.delete(:direct_upload) && respond_to?(:rails_direct_uploads_url)
+            options["data-direct-upload-url"] = rails_direct_uploads_url
+          end
+          options
         end
     end
   end
diff --git a/actionview/lib/action_view/helpers/javascript_helper.rb b/actionview/lib/action_view/helpers/javascript_helper.rb
index ed7e882c94..dd2cd57ac3 100644
--- a/actionview/lib/action_view/helpers/javascript_helper.rb
+++ b/actionview/lib/action_view/helpers/javascript_helper.rb
@@ -1,11 +1,13 @@
-require 'action_view/helpers/tag_helper'
+# frozen_string_literal: true
+
+require "action_view/helpers/tag_helper"
 
 module ActionView
-  module Helpers
+  module Helpers #:nodoc:
     module JavaScriptHelper
       JS_ESCAPE_MAP = {
         '\\'    => '\\\\',
-        '</'    => '<\/',
+        "</"    => '<\/',
         "\r\n"  => '\n',
         "\n"    => '\n',
         "\r"    => '\n',
@@ -13,8 +15,8 @@ module ActionView
         "'"     => "\\'"
       }
 
-      JS_ESCAPE_MAP["\342\200\250".force_encoding(Encoding::UTF_8).encode!] = '&#x2028;'
-      JS_ESCAPE_MAP["\342\200\251".force_encoding(Encoding::UTF_8).encode!] = '&#x2029;'
+      JS_ESCAPE_MAP["\342\200\250".dup.force_encoding(Encoding::UTF_8).encode!] = "&#x2028;"
+      JS_ESCAPE_MAP["\342\200\251".dup.force_encoding(Encoding::UTF_8).encode!] = "&#x2029;"
 
       # Escapes carriage returns and single and double quotes for JavaScript segments.
       #
@@ -24,10 +26,10 @@ module ActionView
       #   $('some_element').replaceWith('<%= j render 'some/element_template' %>');
       def escape_javascript(javascript)
         if javascript
-          result = javascript.gsub(/(\\|<\/|\r\n|\342\200\250|\342\200\251|[\n\r"'])/u) {|match| JS_ESCAPE_MAP[match] }
+          result = javascript.gsub(/(\\|<\/|\r\n|\342\200\250|\342\200\251|[\n\r"'])/u) { |match| JS_ESCAPE_MAP[match] }
           javascript.html_safe? ? result.html_safe : result
         else
-          ''
+          ""
         end
       end
 
diff --git a/actionview/lib/action_view/helpers/number_helper.rb b/actionview/lib/action_view/helpers/number_helper.rb
index 23081c5f07..4b53b8fe6e 100644
--- a/actionview/lib/action_view/helpers/number_helper.rb
+++ b/actionview/lib/action_view/helpers/number_helper.rb
@@ -1,11 +1,12 @@
-require 'active_support/core_ext/hash/keys'
-require 'active_support/core_ext/string/output_safety'
-require 'active_support/number_helper'
+# frozen_string_literal: true
+
+require "active_support/core_ext/hash/keys"
+require "active_support/core_ext/string/output_safety"
+require "active_support/number_helper"
 
 module ActionView
   # = Action View Number Helpers
   module Helpers #:nodoc:
-
     # Provides methods for converting numbers into formatted strings.
     # Methods are provided for phone numbers, currency, percentage,
     # precision, positional notation, file size and pretty printing.
@@ -13,7 +14,6 @@ module ActionView
     # Most methods expect a +number+ argument, and will return it
     # unchanged if can't be converted into a valid number.
     module NumberHelper
-
       # Raised when argument +number+ param given to the helpers is invalid and
       # the option :raise is set to  +true+.
       class InvalidNumberError < StandardError
@@ -94,7 +94,7 @@ module ActionView
       #   (defaults to "%u%n").  Fields are <tt>%u</tt> for the
       #   currency, and <tt>%n</tt> for the number.
       # * <tt>:negative_format</tt> - Sets the format for negative
-      #   numbers (defaults to prepending an hyphen to the formatted
+      #   numbers (defaults to prepending a hyphen to the formatted
       #   number given by <tt>:format</tt>).  Accepts the same fields
       #   than <tt>:format</tt>, except <tt>%n</tt> is here the
       #   absolute value of the number.
@@ -173,6 +173,9 @@ module ActionView
       #   to ",").
       # * <tt>:separator</tt> - Sets the separator between the
       #   fractional and integer digits (defaults to ".").
+      # * <tt>:delimiter_pattern</tt> - Sets a custom regular expression used for
+      #   deriving the placement of delimiter. Helpful when using currency formats
+      #   like INR.
       # * <tt>:raise</tt> - If true, raises +InvalidNumberError+ when
       #   the argument is invalid.
       #
@@ -189,6 +192,9 @@ module ActionView
       #   number_with_delimiter(98765432.98, delimiter: " ", separator: ",")
       #   # => 98 765 432,98
       #
+      #   number_with_delimiter("123456.78",
+      #     delimiter_pattern: /(\d+?)(?=(\d\d)+(\d)(?!\d))/)    # => "1,23,456.78"
+      #
       #  number_with_delimiter("112a", raise: true)              # => raise InvalidNumberError
       def number_with_delimiter(number, options = {})
         delegate_number_helper_method(:number_to_delimited, number, options)
@@ -393,53 +399,53 @@ module ActionView
 
       private
 
-      def delegate_number_helper_method(method, number, options)
-        return unless number
-        options = escape_unsafe_options(options.symbolize_keys)
+        def delegate_number_helper_method(method, number, options)
+          return unless number
+          options = escape_unsafe_options(options.symbolize_keys)
 
-        wrap_with_output_safety_handling(number, options.delete(:raise)) {
-          ActiveSupport::NumberHelper.public_send(method, number, options)
-        }
-      end
+          wrap_with_output_safety_handling(number, options.delete(:raise)) {
+            ActiveSupport::NumberHelper.public_send(method, number, options)
+          }
+        end
 
-      def escape_unsafe_options(options)
-        options[:format]          = ERB::Util.html_escape(options[:format]) if options[:format]
-        options[:negative_format] = ERB::Util.html_escape(options[:negative_format]) if options[:negative_format]
-        options[:separator]       = ERB::Util.html_escape(options[:separator]) if options[:separator]
-        options[:delimiter]       = ERB::Util.html_escape(options[:delimiter]) if options[:delimiter]
-        options[:unit]            = ERB::Util.html_escape(options[:unit]) if options[:unit] && !options[:unit].html_safe?
-        options[:units]           = escape_units(options[:units]) if options[:units] && Hash === options[:units]
-        options
-      end
+        def escape_unsafe_options(options)
+          options[:format]          = ERB::Util.html_escape(options[:format]) if options[:format]
+          options[:negative_format] = ERB::Util.html_escape(options[:negative_format]) if options[:negative_format]
+          options[:separator]       = ERB::Util.html_escape(options[:separator]) if options[:separator]
+          options[:delimiter]       = ERB::Util.html_escape(options[:delimiter]) if options[:delimiter]
+          options[:unit]            = ERB::Util.html_escape(options[:unit]) if options[:unit] && !options[:unit].html_safe?
+          options[:units]           = escape_units(options[:units]) if options[:units] && Hash === options[:units]
+          options
+        end
 
-      def escape_units(units)
-        Hash[units.map do |k, v|
-          [k, ERB::Util.html_escape(v)]
-        end]
-      end
+        def escape_units(units)
+          Hash[units.map do |k, v|
+            [k, ERB::Util.html_escape(v)]
+          end]
+        end
 
-      def wrap_with_output_safety_handling(number, raise_on_invalid, &block)
-        valid_float = valid_float?(number)
-        raise InvalidNumberError, number if raise_on_invalid && !valid_float
+        def wrap_with_output_safety_handling(number, raise_on_invalid, &block)
+          valid_float = valid_float?(number)
+          raise InvalidNumberError, number if raise_on_invalid && !valid_float
 
-        formatted_number = yield
+          formatted_number = yield
 
-        if valid_float || number.html_safe?
-          formatted_number.html_safe
-        else
-          formatted_number
+          if valid_float || number.html_safe?
+            formatted_number.html_safe
+          else
+            formatted_number
+          end
         end
-      end
 
-      def valid_float?(number)
-        !parse_float(number, false).nil?
-      end
+        def valid_float?(number)
+          !parse_float(number, false).nil?
+        end
 
-      def parse_float(number, raise_error)
-        Float(number)
-      rescue ArgumentError, TypeError
-        raise InvalidNumberError, number if raise_error
-      end
+        def parse_float(number, raise_error)
+          Float(number)
+        rescue ArgumentError, TypeError
+          raise InvalidNumberError, number if raise_error
+        end
     end
   end
 end
diff --git a/actionview/lib/action_view/helpers/output_safety_helper.rb b/actionview/lib/action_view/helpers/output_safety_helper.rb
index d4b55423a8..279cde5e76 100644
--- a/actionview/lib/action_view/helpers/output_safety_helper.rb
+++ b/actionview/lib/action_view/helpers/output_safety_helper.rb
@@ -1,4 +1,6 @@
-require 'active_support/core_ext/string/output_safety'
+# frozen_string_literal: true
+
+require "active_support/core_ext/string/output_safety"
 
 module ActionView #:nodoc:
   # = Action View Raw Output Helper
@@ -25,10 +27,10 @@ module ActionView #:nodoc:
       #   safe_join([raw("<p>foo</p>"), "<p>bar</p>"], "<br />")
       #   # => "<p>foo</p>&lt;br /&gt;&lt;p&gt;bar&lt;/p&gt;"
       #
-      #   safe_join([raw("<p>foo</p>"), raw("<p>bar</p>")], raw("<br />")
+      #   safe_join([raw("<p>foo</p>"), raw("<p>bar</p>")], raw("<br />"))
       #   # => "<p>foo</p><br /><p>bar</p>"
       #
-      def safe_join(array, sep=$,)
+      def safe_join(array, sep = $,)
         sep = ERB::Util.unwrapped_html_escape(sep)
 
         array.flatten.map! { |i| ERB::Util.unwrapped_html_escape(i) }.join(sep).html_safe
@@ -42,9 +44,9 @@ module ActionView #:nodoc:
         options.assert_valid_keys(:words_connector, :two_words_connector, :last_word_connector, :locale)
 
         default_connectors = {
-          :words_connector     => ', ',
-          :two_words_connector => ' and ',
-          :last_word_connector => ', and '
+          words_connector: ", ",
+          two_words_connector: " and ",
+          last_word_connector: ", and "
         }
         if defined?(I18n)
           i18n_connectors = I18n.translate(:'support.array', locale: options[:locale], default: {})
@@ -54,13 +56,13 @@ module ActionView #:nodoc:
 
         case array.length
         when 0
-          ''.html_safe
+          "".html_safe
         when 1
           ERB::Util.html_escape(array[0])
         when 2
           safe_join([array[0], array[1]], options[:two_words_connector])
         else
-          safe_join([safe_join(array[0...-1], options[:words_connector]), options[:last_word_connector], array[-1]])
+          safe_join([safe_join(array[0...-1], options[:words_connector]), options[:last_word_connector], array[-1]], nil)
         end
       end
     end
diff --git a/actionview/lib/action_view/helpers/record_tag_helper.rb b/actionview/lib/action_view/helpers/record_tag_helper.rb
index f7ee573035..a6953ee905 100644
--- a/actionview/lib/action_view/helpers/record_tag_helper.rb
+++ b/actionview/lib/action_view/helpers/record_tag_helper.rb
@@ -1,7 +1,9 @@
+# frozen_string_literal: true
+
 module ActionView
-  module Helpers
+  module Helpers #:nodoc:
     module RecordTagHelper
-      def div_for(*)
+      def div_for(*) # :nodoc:
         raise NoMethodError, "The `div_for` method has been removed from " \
           "Rails. To continue using it, add the `record_tag_helper` gem to " \
           "your Gemfile:\n" \
@@ -9,7 +11,7 @@ module ActionView
           "Consult the Rails upgrade guide for details."
       end
 
-      def content_tag_for(*)
+      def content_tag_for(*) # :nodoc:
         raise NoMethodError, "The `content_tag_for` method has been removed from " \
           "Rails. To continue using it, add the `record_tag_helper` gem to " \
           "your Gemfile:\n" \
diff --git a/actionview/lib/action_view/helpers/rendering_helper.rb b/actionview/lib/action_view/helpers/rendering_helper.rb
index c98f2d74a8..8e505ab054 100644
--- a/actionview/lib/action_view/helpers/rendering_helper.rb
+++ b/actionview/lib/action_view/helpers/rendering_helper.rb
@@ -1,5 +1,7 @@
+# frozen_string_literal: true
+
 module ActionView
-  module Helpers
+  module Helpers #:nodoc:
     # = Action View Rendering
     #
     # Implements methods that allow rendering from a view context.
@@ -27,12 +29,12 @@ module ActionView
         case options
         when Hash
           if block_given?
-            view_renderer.render_partial(self, options.merge(:partial => options[:layout]), &block)
+            view_renderer.render_partial(self, options.merge(partial: options[:layout]), &block)
           else
             view_renderer.render(self, options)
           end
         else
-          view_renderer.render_partial(self, :partial => options, :locals => locals, &block)
+          view_renderer.render_partial(self, partial: options, locals: locals, &block)
         end
       end
 
diff --git a/actionview/lib/action_view/helpers/sanitize_helper.rb b/actionview/lib/action_view/helpers/sanitize_helper.rb
index f9784c3483..275a2dffb4 100644
--- a/actionview/lib/action_view/helpers/sanitize_helper.rb
+++ b/actionview/lib/action_view/helpers/sanitize_helper.rb
@@ -1,9 +1,11 @@
-require 'active_support/core_ext/object/try'
-require 'rails-html-sanitizer'
+# frozen_string_literal: true
+
+require "active_support/core_ext/object/try"
+require "rails-html-sanitizer"
 
 module ActionView
   # = Action View Sanitize Helpers
-  module Helpers
+  module Helpers #:nodoc:
     # The SanitizeHelper module provides a set of methods for scrubbing text of undesired HTML elements.
     # These helper methods extend Action View making them callable within your template files.
     module SanitizeHelper
@@ -13,6 +15,7 @@ module ActionView
       # It also strips href/src attributes with unsafe protocols like
       # <tt>javascript:</tt>, while also protecting against attempts to use Unicode,
       # ASCII, and hex character references to work around these protocol filters.
+      # All special characters will be escaped.
       #
       # The default sanitizer is Rails::Html::WhiteListSanitizer. See {Rails HTML
       # Sanitizers}[https://github.com/rails/rails-html-sanitizer] for more information.
@@ -20,8 +23,7 @@ module ActionView
       # Custom sanitization rules can also be provided.
       #
       # Please note that sanitizing user-provided text does not guarantee that the
-      # resulting markup is valid or even well-formed. For example, the output may still
-      # contain unescaped characters like <tt><</tt>, <tt>></tt>, or <tt>&</tt>.
+      # resulting markup is valid or even well-formed.
       #
       # ==== Options
       #
@@ -45,17 +47,15 @@ module ActionView
       # Providing a custom Rails::Html scrubber:
       #
       #   class CommentScrubber < Rails::Html::PermitScrubber
-      #     def allowed_node?(node)
-      #       !%w(form script comment blockquote).include?(node.name)
+      #     def initialize
+      #       super
+      #       self.tags = %w( form script comment blockquote )
+      #       self.attributes = %w( style )
       #     end
       #
       #     def skip_node?(node)
       #       node.text?
       #     end
-      #
-      #     def scrub_attribute?(name)
-      #       name == 'style'
-      #     end
       #   end
       #
       #   <%= sanitize @comment.body, scrubber: CommentScrubber.new %>
@@ -88,7 +88,7 @@ module ActionView
         self.class.white_list_sanitizer.sanitize_css(style)
       end
 
-      # Strips all HTML tags from +html+, including comments.
+      # Strips all HTML tags from +html+, including comments and special characters.
       #
       #   strip_tags("Strip <i>these</i> tags!")
       #   # => Strip these tags!
@@ -98,8 +98,11 @@ module ActionView
       #
       #   strip_tags("<div id='top-bar'>Welcome to my website!</div>")
       #   # => Welcome to my website!
+      #
+      #   strip_tags("> A quote from Smith & Wesson")
+      #   # => &gt; A quote from Smith &amp; Wesson
       def strip_tags(html)
-        self.class.full_sanitizer.sanitize(html, encode_special_chars: false)
+        self.class.full_sanitizer.sanitize(html)
       end
 
       # Strips all link tags from +html+ leaving just the link text.
@@ -112,6 +115,9 @@ module ActionView
       #
       #   strip_links('Blog: <a href="http://www.myblog.com/" class="nav" target=\"_blank\">Visit</a>.')
       #   # => Blog: Visit.
+      #
+      #   strip_links('<<a href="https://example.org">malformed & link</a>')
+      #   # => &lt;malformed &amp; link
       def strip_links(html)
         self.class.link_sanitizer.sanitize(html)
       end
diff --git a/actionview/lib/action_view/helpers/tag_helper.rb b/actionview/lib/action_view/helpers/tag_helper.rb
index 42e7358a1d..a6cec3f69c 100644
--- a/actionview/lib/action_view/helpers/tag_helper.rb
+++ b/actionview/lib/action_view/helpers/tag_helper.rb
@@ -1,39 +1,207 @@
-require 'active_support/core_ext/string/output_safety'
-require 'set'
+# frozen_string_literal: true
+
+require "active_support/core_ext/string/output_safety"
+require "set"
 
 module ActionView
   # = Action View Tag Helpers
   module Helpers #:nodoc:
-    # Provides methods to generate HTML tags programmatically when you can't use
-    # a Builder. By default, they output XHTML compliant tags.
+    # Provides methods to generate HTML tags programmatically both as a modern
+    # HTML5 compliant builder style and legacy XHTML compliant tags.
     module TagHelper
       extend ActiveSupport::Concern
       include CaptureHelper
       include OutputSafetyHelper
 
-      BOOLEAN_ATTRIBUTES = %w(disabled readonly multiple checked autobuffer
-                           autoplay controls loop selected hidden scoped async
-                           defer reversed ismap seamless muted required
-                           autofocus novalidate formnovalidate open pubdate
-                           itemscope allowfullscreen default inert sortable
-                           truespeed typemustmatch).to_set
+      BOOLEAN_ATTRIBUTES = %w(allowfullscreen async autofocus autoplay checked
+                              compact controls declare default defaultchecked
+                              defaultmuted defaultselected defer disabled
+                              enabled formnovalidate hidden indeterminate inert
+                              ismap itemscope loop multiple muted nohref
+                              noresize noshade novalidate nowrap open
+                              pauseonexit readonly required reversed scoped
+                              seamless selected sortable truespeed typemustmatch
+                              visible).to_set
 
       BOOLEAN_ATTRIBUTES.merge(BOOLEAN_ATTRIBUTES.map(&:to_sym))
 
-      TAG_PREFIXES = ['aria', 'data', :aria, :data].to_set
+      TAG_PREFIXES = ["aria", "data", :aria, :data].to_set
 
-      PRE_CONTENT_STRINGS             = Hash.new { "".freeze }
+      PRE_CONTENT_STRINGS             = Hash.new { "" }
       PRE_CONTENT_STRINGS[:textarea]  = "\n"
       PRE_CONTENT_STRINGS["textarea"] = "\n"
 
+      class TagBuilder #:nodoc:
+        include CaptureHelper
+        include OutputSafetyHelper
+
+        VOID_ELEMENTS = %i(area base br col embed hr img input keygen link meta param source track wbr).to_set
+
+        def initialize(view_context)
+          @view_context = view_context
+        end
+
+        def tag_string(name, content = nil, escape_attributes: true, **options, &block)
+          content = @view_context.capture(self, &block) if block_given?
+          if VOID_ELEMENTS.include?(name) && content.nil?
+            "<#{name.to_s.dasherize}#{tag_options(options, escape_attributes)}>".html_safe
+          else
+            content_tag_string(name.to_s.dasherize, content || "", options, escape_attributes)
+          end
+        end
+
+        def content_tag_string(name, content, options, escape = true)
+          tag_options = tag_options(options, escape) if options
+          content     = ERB::Util.unwrapped_html_escape(content) if escape
+          "<#{name}#{tag_options}>#{PRE_CONTENT_STRINGS[name]}#{content}</#{name}>".html_safe
+        end
+
+        def tag_options(options, escape = true)
+          return if options.blank?
+          output = "".dup
+          sep    = " "
+          options.each_pair do |key, value|
+            if TAG_PREFIXES.include?(key) && value.is_a?(Hash)
+              value.each_pair do |k, v|
+                next if v.nil?
+                output << sep
+                output << prefix_tag_option(key, k, v, escape)
+              end
+            elsif BOOLEAN_ATTRIBUTES.include?(key)
+              if value
+                output << sep
+                output << boolean_tag_option(key)
+              end
+            elsif !value.nil?
+              output << sep
+              output << tag_option(key, value, escape)
+            end
+          end
+          output unless output.empty?
+        end
+
+        def boolean_tag_option(key)
+          %(#{key}="#{key}")
+        end
+
+        def tag_option(key, value, escape)
+          if value.is_a?(Array)
+            value = escape ? safe_join(value, " ".freeze) : value.join(" ".freeze)
+          else
+            value = escape ? ERB::Util.unwrapped_html_escape(value) : value.to_s
+          end
+          %(#{key}="#{value.gsub('"'.freeze, '&quot;'.freeze)}")
+        end
+
+        private
+          def prefix_tag_option(prefix, key, value, escape)
+            key = "#{prefix}-#{key.to_s.dasherize}"
+            unless value.is_a?(String) || value.is_a?(Symbol) || value.is_a?(BigDecimal)
+              value = value.to_json
+            end
+            tag_option(key, value, escape)
+          end
+
+          def respond_to_missing?(*args)
+            true
+          end
+
+          def method_missing(called, *args, &block)
+            tag_string(called, *args, &block)
+          end
+      end
 
-      # Returns an empty HTML tag of type +name+ which by default is XHTML
+      # Returns an HTML tag.
+      #
+      # === Building HTML tags
+      #
+      # Builds HTML5 compliant tags with a tag proxy. Every tag can be built with:
+      #
+      #   tag.<tag name>(optional content, options)
+      #
+      # where tag name can be e.g. br, div, section, article, or any tag really.
+      #
+      # ==== Passing content
+      #
+      # Tags can pass content to embed within it:
+      #
+      #   tag.h1 'All titles fit to print' # => <h1>All titles fit to print</h1>
+      #
+      #   tag.div tag.p('Hello world!')  # => <div><p>Hello world!</p></div>
+      #
+      # Content can also be captured with a block, which is useful in templates:
+      #
+      #   <%= tag.p do %>
+      #     The next great American novel starts here.
+      #   <% end %>
+      #   # => <p>The next great American novel starts here.</p>
+      #
+      # ==== Options
+      #
+      # Use symbol keyed options to add attributes to the generated tag.
+      #
+      #   tag.section class: %w( kitties puppies )
+      #   # => <section class="kitties puppies"></section>
+      #
+      #   tag.section id: dom_id(@post)
+      #   # => <section id="<generated dom id>"></section>
+      #
+      # Pass +true+ for any attributes that can render with no values, like +disabled+ and +readonly+.
+      #
+      #   tag.input type: 'text', disabled: true
+      #   # => <input type="text" disabled="disabled">
+      #
+      # HTML5 <tt>data-*</tt> attributes can be set with a single +data+ key
+      # pointing to a hash of sub-attributes.
+      #
+      # To play nicely with JavaScript conventions, sub-attributes are dasherized.
+      #
+      #   tag.article data: { user_id: 123 }
+      #   # => <article data-user-id="123"></article>
+      #
+      # Thus <tt>data-user-id</tt> can be accessed as <tt>dataset.userId</tt>.
+      #
+      # Data attribute values are encoded to JSON, with the exception of strings, symbols and
+      # BigDecimals.
+      # This may come in handy when using jQuery's HTML5-aware <tt>.data()</tt>
+      # from 1.4.3.
+      #
+      #   tag.div data: { city_state: %w( Chicago IL ) }
+      #   # => <div data-city-state="[&quot;Chicago&quot;,&quot;IL&quot;]"></div>
+      #
+      # The generated attributes are escaped by default. This can be disabled using
+      # +escape_attributes+.
+      #
+      #   tag.img src: 'open & shut.png'
+      #   # => <img src="open &amp; shut.png">
+      #
+      #   tag.img src: 'open & shut.png', escape_attributes: false
+      #   # => <img src="open & shut.png">
+      #
+      # The tag builder respects
+      # {HTML5 void elements}[https://www.w3.org/TR/html5/syntax.html#void-elements]
+      # if no content is passed, and omits closing tags for those elements.
+      #
+      #   # A standard element:
+      #   tag.div # => <div></div>
+      #
+      #   # A void element:
+      #   tag.br  # => <br>
+      #
+      # === Legacy syntax
+      #
+      # The following format is for legacy syntax support. It will be deprecated in future versions of Rails.
+      #
+      #   tag(name, options = nil, open = false, escape = true)
+      #
+      # It returns an empty HTML tag of type +name+ which by default is XHTML
       # compliant. Set +open+ to true to create an open tag compatible
       # with HTML 4.0 and below. Add HTML attributes by passing an attributes
       # hash to +options+. Set +escape+ to false to disable attribute value
       # escaping.
       #
       # ==== Options
+      #
       # You can use symbols or strings for the attribute names.
       #
       # Use +true+ with boolean attributes that can render with no value, like
@@ -42,16 +210,8 @@ module ActionView
       # HTML5 <tt>data-*</tt> attributes can be set with a single +data+ key
       # pointing to a hash of sub-attributes.
       #
-      # To play nicely with JavaScript conventions sub-attributes are dasherized.
-      # For example, a key +user_id+ would render as <tt>data-user-id</tt> and
-      # thus accessed as <tt>dataset.userId</tt>.
-      #
-      # Values are encoded to JSON, with the exception of strings, symbols and
-      # BigDecimals.
-      # This may come in handy when using jQuery's HTML5-aware <tt>.data()</tt>
-      # from 1.4.3.
-      #
       # ==== Examples
+      #
       #   tag("br")
       #   # => <br />
       #
@@ -72,8 +232,12 @@ module ActionView
       #
       #   tag("div", data: {name: 'Stephen', city_state: %w(Chicago IL)})
       #   # => <div data-name="Stephen" data-city-state="[&quot;Chicago&quot;,&quot;IL&quot;]" />
-      def tag(name, options = nil, open = false, escape = true)
-        "<#{name}#{tag_options(options, escape) if options}#{open ? ">" : " />"}".html_safe
+      def tag(name = nil, options = nil, open = false, escape = true)
+        if name.nil?
+          tag_builder
+        else
+          "<#{name}#{tag_builder.tag_options(options, escape) if options}#{open ? ">" : " />"}".html_safe
+        end
       end
 
       # Returns an HTML block tag of type +name+ surrounding the +content+. Add
@@ -81,6 +245,7 @@ module ActionView
       # Instead of passing the content as an argument, you can also use a block
       # in which case, you pass your +options+ as the second parameter.
       # Set escape to false to disable attribute value escaping.
+      # Note: this is legacy syntax, see +tag+ method description for details.
       #
       # ==== Options
       # The +options+ hash can be used with attributes with no value like (<tt>disabled</tt> and
@@ -104,9 +269,9 @@ module ActionView
       def content_tag(name, content_or_options_with_block = nil, options = nil, escape = true, &block)
         if block_given?
           options = content_or_options_with_block if content_or_options_with_block.is_a?(Hash)
-          content_tag_string(name, capture(&block), options, escape)
+          tag_builder.content_tag_string(name, capture(&block), options, escape)
         else
-          content_tag_string(name, content_or_options_with_block, options, escape)
+          tag_builder.content_tag_string(name, content_or_options_with_block, options, escape)
         end
       end
 
@@ -124,7 +289,7 @@ module ActionView
       #   cdata_section("hello]]>world")
       #   # => <![CDATA[hello]]]]><![CDATA[>world]]>
       def cdata_section(content)
-        splitted = content.to_s.gsub(/\]\]\>/, ']]]]><![CDATA[>')
+        splitted = content.to_s.gsub(/\]\]\>/, "]]]]><![CDATA[>")
         "<![CDATA[#{splitted}]]>".html_safe
       end
 
@@ -140,56 +305,8 @@ module ActionView
       end
 
       private
-
-        def content_tag_string(name, content, options, escape = true)
-          tag_options = tag_options(options, escape) if options
-          content     = ERB::Util.unwrapped_html_escape(content) if escape
-          "<#{name}#{tag_options}>#{PRE_CONTENT_STRINGS[name]}#{content}</#{name}>".html_safe
-        end
-
-        def tag_options(options, escape = true)
-          return if options.blank?
-          output = ""
-          sep    = " ".freeze
-          options.each_pair do |key, value|
-            if TAG_PREFIXES.include?(key) && value.is_a?(Hash)
-              value.each_pair do |k, v|
-                next if v.nil?
-                output << sep
-                output << prefix_tag_option(key, k, v, escape)
-              end
-            elsif BOOLEAN_ATTRIBUTES.include?(key)
-              if value
-                output << sep
-                output << boolean_tag_option(key)
-              end
-            elsif !value.nil?
-              output << sep
-              output << tag_option(key, value, escape)
-            end
-          end
-          output unless output.empty?
-        end
-
-        def prefix_tag_option(prefix, key, value, escape)
-          key = "#{prefix}-#{key.to_s.dasherize}"
-          unless value.is_a?(String) || value.is_a?(Symbol) || value.is_a?(BigDecimal)
-            value = value.to_json
-          end
-          tag_option(key, value, escape)
-        end
-
-        def boolean_tag_option(key)
-          %(#{key}="#{key}")
-        end
-
-        def tag_option(key, value, escape)
-          if value.is_a?(Array)
-            value = escape ? safe_join(value, " ".freeze) : value.join(" ".freeze)
-          else
-            value = escape ? ERB::Util.unwrapped_html_escape(value) : value
-          end
-          %(#{key}="#{value}")
+        def tag_builder
+          @tag_builder ||= TagBuilder.new(self)
         end
     end
   end
diff --git a/actionview/lib/action_view/helpers/tags.rb b/actionview/lib/action_view/helpers/tags.rb
index a4f6eb0150..566668b958 100644
--- a/actionview/lib/action_view/helpers/tags.rb
+++ b/actionview/lib/action_view/helpers/tags.rb
@@ -1,5 +1,7 @@
+# frozen_string_literal: true
+
 module ActionView
-  module Helpers
+  module Helpers #:nodoc:
     module Tags #:nodoc:
       extend ActiveSupport::Autoload
 
diff --git a/actionview/lib/action_view/helpers/tags/base.rb b/actionview/lib/action_view/helpers/tags/base.rb
index d57f26ba4f..fed908fcdb 100644
--- a/actionview/lib/action_view/helpers/tags/base.rb
+++ b/actionview/lib/action_view/helpers/tags/base.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActionView
   module Helpers
     module Tags # :nodoc:
@@ -11,10 +13,19 @@ module ActionView
           @object_name, @method_name = object_name.to_s.dup, method_name.to_s.dup
           @template_object = template_object
 
-          @object_name.sub!(/\[\]$/,"") || @object_name.sub!(/\[\]\]$/,"]")
+          @object_name.sub!(/\[\]$/, "") || @object_name.sub!(/\[\]\]$/, "]")
           @object = retrieve_object(options.delete(:object))
+          @skip_default_ids = options.delete(:skip_default_ids)
+          @allow_method_names_outside_object = options.delete(:allow_method_names_outside_object)
           @options = options
-          @auto_index = Regexp.last_match ? retrieve_autoindex(Regexp.last_match.pre_match) : nil
+
+          if Regexp.last_match
+            @generate_indexed_names = true
+            @auto_index = retrieve_autoindex(Regexp.last_match.pre_match)
+          else
+            @generate_indexed_names = false
+            @auto_index = nil
+          end
         end
 
         # This is what child classes implement.
@@ -24,136 +35,157 @@ module ActionView
 
         private
 
-        def value(object)
-          object.public_send @method_name if object
-        end
+          def value
+            if @allow_method_names_outside_object
+              object.public_send @method_name if object && object.respond_to?(@method_name)
+            else
+              object.public_send @method_name if object
+            end
+          end
 
-        def value_before_type_cast(object)
-          unless object.nil?
-            method_before_type_cast = @method_name + "_before_type_cast"
+          def value_before_type_cast
+            unless object.nil?
+              method_before_type_cast = @method_name + "_before_type_cast"
 
-            if value_came_from_user?(object) && object.respond_to?(method_before_type_cast)
-              object.public_send(method_before_type_cast)
-            else
-              value(object)
+              if value_came_from_user? && object.respond_to?(method_before_type_cast)
+                object.public_send(method_before_type_cast)
+              else
+                value
+              end
             end
           end
-        end
 
-        def value_came_from_user?(object)
-          method_name = "#{@method_name}_came_from_user?"
-          !object.respond_to?(method_name) || object.public_send(method_name)
-        end
+          def value_came_from_user?
+            method_name = "#{@method_name}_came_from_user?"
+            !object.respond_to?(method_name) || object.public_send(method_name)
+          end
 
-        def retrieve_object(object)
-          if object
-            object
-          elsif @template_object.instance_variable_defined?("@#{@object_name}")
-            @template_object.instance_variable_get("@#{@object_name}")
+          def retrieve_object(object)
+            if object
+              object
+            elsif @template_object.instance_variable_defined?("@#{@object_name}")
+              @template_object.instance_variable_get("@#{@object_name}")
+            end
+          rescue NameError
+            # As @object_name may contain the nested syntax (item[subobject]) we need to fallback to nil.
+            nil
           end
-        rescue NameError
-          # As @object_name may contain the nested syntax (item[subobject]) we need to fallback to nil.
-          nil
-        end
 
-        def retrieve_autoindex(pre_match)
-          object = self.object || @template_object.instance_variable_get("@#{pre_match}")
-          if object && object.respond_to?(:to_param)
-            object.to_param
-          else
-            raise ArgumentError, "object[] naming but object param and @object var don't exist or don't respond to to_param: #{object.inspect}"
+          def retrieve_autoindex(pre_match)
+            object = self.object || @template_object.instance_variable_get("@#{pre_match}")
+            if object && object.respond_to?(:to_param)
+              object.to_param
+            else
+              raise ArgumentError, "object[] naming but object param and @object var don't exist or don't respond to to_param: #{object.inspect}"
+            end
           end
-        end
 
-        def add_default_name_and_id_for_value(tag_value, options)
-          if tag_value.nil?
-            add_default_name_and_id(options)
-          else
-            specified_id = options["id"]
-            add_default_name_and_id(options)
+          def add_default_name_and_id_for_value(tag_value, options)
+            if tag_value.nil?
+              add_default_name_and_id(options)
+            else
+              specified_id = options["id"]
+              add_default_name_and_id(options)
 
-            if specified_id.blank? && options["id"].present?
-              options["id"] += "_#{sanitized_value(tag_value)}"
+              if specified_id.blank? && options["id"].present?
+                options["id"] += "_#{sanitized_value(tag_value)}"
+              end
             end
           end
-        end
 
-        def add_default_name_and_id(options)
-          index = name_and_id_index(options)
-          options["name"] = options.fetch("name"){ tag_name(options["multiple"], index) }
-          options["id"] = options.fetch("id"){ tag_id(index) }
-          if namespace = options.delete("namespace")
-            options['id'] = options['id'] ? "#{namespace}_#{options['id']}" : namespace
+          def add_default_name_and_id(options)
+            index = name_and_id_index(options)
+            options["name"] = options.fetch("name") { tag_name(options["multiple"], index) }
+
+            if generate_ids?
+              options["id"] = options.fetch("id") { tag_id(index) }
+              if namespace = options.delete("namespace")
+                options["id"] = options["id"] ? "#{namespace}_#{options['id']}" : namespace
+              end
+            end
           end
-        end
 
-        def tag_name(multiple = false, index = nil)
-          # a little duplication to construct less strings
-          if index
-            "#{@object_name}[#{index}][#{sanitized_method_name}]#{"[]" if multiple}"
-          else
-            "#{@object_name}[#{sanitized_method_name}]#{"[]" if multiple}"
+          def tag_name(multiple = false, index = nil)
+            # a little duplication to construct less strings
+            case
+            when @object_name.empty?
+              "#{sanitized_method_name}#{"[]" if multiple}"
+            when index
+              "#{@object_name}[#{index}][#{sanitized_method_name}]#{"[]" if multiple}"
+            else
+              "#{@object_name}[#{sanitized_method_name}]#{"[]" if multiple}"
+            end
           end
-        end
 
-        def tag_id(index = nil)
-          # a little duplication to construct less strings
-          if index
-            "#{sanitized_object_name}_#{index}_#{sanitized_method_name}"
-          else
-            "#{sanitized_object_name}_#{sanitized_method_name}"
+          def tag_id(index = nil)
+            # a little duplication to construct less strings
+            case
+            when @object_name.empty?
+              sanitized_method_name.dup
+            when index
+              "#{sanitized_object_name}_#{index}_#{sanitized_method_name}"
+            else
+              "#{sanitized_object_name}_#{sanitized_method_name}"
+            end
           end
-        end
 
-        def sanitized_object_name
-          @sanitized_object_name ||= @object_name.gsub(/\]\[|[^-a-zA-Z0-9:.]/, "_").sub(/_$/, "")
-        end
+          def sanitized_object_name
+            @sanitized_object_name ||= @object_name.gsub(/\]\[|[^-a-zA-Z0-9:.]/, "_").sub(/_$/, "")
+          end
 
-        def sanitized_method_name
-          @sanitized_method_name ||= @method_name.sub(/\?$/,"")
-        end
+          def sanitized_method_name
+            @sanitized_method_name ||= @method_name.sub(/\?$/, "")
+          end
 
-        def sanitized_value(value)
-          value.to_s.gsub(/\s/, "_").gsub(/[^-\w]/, "").downcase
-        end
+          def sanitized_value(value)
+            value.to_s.gsub(/\s/, "_").gsub(/[^-[[:word:]]]/, "").mb_chars.downcase.to_s
+          end
 
-        def select_content_tag(option_tags, options, html_options)
-          html_options = html_options.stringify_keys
-          add_default_name_and_id(html_options)
+          def select_content_tag(option_tags, options, html_options)
+            html_options = html_options.stringify_keys
+            add_default_name_and_id(html_options)
 
-          if placeholder_required?(html_options)
-            raise ArgumentError, "include_blank cannot be false for a required field." if options[:include_blank] == false
-            options[:include_blank] ||= true unless options[:prompt]
-          end
+            if placeholder_required?(html_options)
+              raise ArgumentError, "include_blank cannot be false for a required field." if options[:include_blank] == false
+              options[:include_blank] ||= true unless options[:prompt]
+            end
 
-          value = options.fetch(:selected) { value(object) }
-          select = content_tag("select", add_options(option_tags, options, value), html_options)
+            value = options.fetch(:selected) { value() }
+            select = content_tag("select", add_options(option_tags, options, value), html_options)
 
-          if html_options["multiple"] && options.fetch(:include_hidden, true)
-            tag("input", :disabled => html_options["disabled"], :name => html_options["name"], :type => "hidden", :value => "") + select
-          else
-            select
+            if html_options["multiple"] && options.fetch(:include_hidden, true)
+              tag("input", disabled: html_options["disabled"], name: html_options["name"], type: "hidden", value: "") + select
+            else
+              select
+            end
           end
-        end
 
-        def placeholder_required?(html_options)
-          # See https://html.spec.whatwg.org/multipage/forms.html#attr-select-required
-          html_options["required"] && !html_options["multiple"] && html_options.fetch("size", 1).to_i == 1
-        end
+          def placeholder_required?(html_options)
+            # See https://html.spec.whatwg.org/multipage/forms.html#attr-select-required
+            html_options["required"] && !html_options["multiple"] && html_options.fetch("size", 1).to_i == 1
+          end
 
-        def add_options(option_tags, options, value = nil)
-          if options[:include_blank]
-            option_tags = content_tag_string('option', options[:include_blank].kind_of?(String) ? options[:include_blank] : nil, :value => '') + "\n" + option_tags
+          def add_options(option_tags, options, value = nil)
+            if options[:include_blank]
+              option_tags = tag_builder.content_tag_string("option", options[:include_blank].kind_of?(String) ? options[:include_blank] : nil, value: "") + "\n" + option_tags
+            end
+            if value.blank? && options[:prompt]
+              option_tags = tag_builder.content_tag_string("option", prompt_text(options[:prompt]), value: "") + "\n" + option_tags
+            end
+            option_tags
           end
-          if value.blank? && options[:prompt]
-            option_tags = content_tag_string('option', prompt_text(options[:prompt]), :value => '') + "\n" + option_tags
+
+          def name_and_id_index(options)
+            if options.key?("index")
+              options.delete("index") || ""
+            elsif @generate_indexed_names
+              @auto_index || ""
+            end
           end
-          option_tags
-        end
 
-        def name_and_id_index(options)
-          options.key?("index") ?  options.delete("index") || "" : @auto_index
-        end
+          def generate_ids?
+            !@skip_default_ids
+          end
       end
     end
   end
diff --git a/actionview/lib/action_view/helpers/tags/check_box.rb b/actionview/lib/action_view/helpers/tags/check_box.rb
index 6d51f2629a..4327e07cae 100644
--- a/actionview/lib/action_view/helpers/tags/check_box.rb
+++ b/actionview/lib/action_view/helpers/tags/check_box.rb
@@ -1,4 +1,6 @@
-require 'action_view/helpers/tags/checkable'
+# frozen_string_literal: true
+
+require "action_view/helpers/tags/checkable"
 
 module ActionView
   module Helpers
@@ -16,7 +18,7 @@ module ActionView
           options = @options.stringify_keys
           options["type"]     = "checkbox"
           options["value"]    = @checked_value
-          options["checked"] = "checked" if input_checked?(object, options)
+          options["checked"] = "checked" if input_checked?(options)
 
           if options["multiple"]
             add_default_name_and_id_for_value(@checked_value, options)
@@ -38,26 +40,26 @@ module ActionView
 
         private
 
-        def checked?(value)
-          case value
-          when TrueClass, FalseClass
-            value == !!@checked_value
-          when NilClass
-            false
-          when String
-            value == @checked_value
-          else
-            if value.respond_to?(:include?)
-              value.include?(@checked_value)
+          def checked?(value)
+            case value
+            when TrueClass, FalseClass
+              value == !!@checked_value
+            when NilClass
+              false
+            when String
+              value == @checked_value
             else
-              value.to_i == @checked_value.to_i
+              if value.respond_to?(:include?)
+                value.include?(@checked_value)
+              else
+                value.to_i == @checked_value.to_i
+              end
             end
           end
-        end
 
-        def hidden_field_for_checkbox(options)
-          @unchecked_value ? tag("input", options.slice("name", "disabled", "form").merge!("type" => "hidden", "value" => @unchecked_value)) : "".html_safe
-        end
+          def hidden_field_for_checkbox(options)
+            @unchecked_value ? tag("input", options.slice("name", "disabled", "form").merge!("type" => "hidden", "value" => @unchecked_value)) : "".html_safe
+          end
       end
     end
   end
diff --git a/actionview/lib/action_view/helpers/tags/checkable.rb b/actionview/lib/action_view/helpers/tags/checkable.rb
index 052e9df662..776fefe778 100644
--- a/actionview/lib/action_view/helpers/tags/checkable.rb
+++ b/actionview/lib/action_view/helpers/tags/checkable.rb
@@ -1,13 +1,15 @@
+# frozen_string_literal: true
+
 module ActionView
   module Helpers
     module Tags # :nodoc:
       module Checkable # :nodoc:
-        def input_checked?(object, options)
+        def input_checked?(options)
           if options.has_key?("checked")
             checked = options.delete "checked"
             checked == true || checked == "checked"
           else
-            checked?(value(object))
+            checked?(value)
           end
         end
       end
diff --git a/actionview/lib/action_view/helpers/tags/collection_check_boxes.rb b/actionview/lib/action_view/helpers/tags/collection_check_boxes.rb
index 3dda47a458..455442178e 100644
--- a/actionview/lib/action_view/helpers/tags/collection_check_boxes.rb
+++ b/actionview/lib/action_view/helpers/tags/collection_check_boxes.rb
@@ -1,4 +1,6 @@
-require 'action_view/helpers/tags/collection_helpers'
+# frozen_string_literal: true
+
+require "action_view/helpers/tags/collection_helpers"
 
 module ActionView
   module Helpers
@@ -7,9 +9,10 @@ module ActionView
         include CollectionHelpers
 
         class CheckBoxBuilder < Builder # :nodoc:
-          def check_box(extra_html_options={})
+          def check_box(extra_html_options = {})
             html_options = extra_html_options.merge(@input_html_options)
             html_options[:multiple] = true
+            html_options[:skip_default_ids] = false
             @template_object.check_box(@object_name, @method_name, html_options, @value, nil)
           end
         end
@@ -20,13 +23,13 @@ module ActionView
 
         private
 
-        def render_component(builder)
-          builder.check_box + builder.label
-        end
+          def render_component(builder)
+            builder.check_box + builder.label
+          end
 
-        def hidden_field_name #:nodoc:
-          "#{super}[]"
-        end
+          def hidden_field_name
+            "#{super}[]"
+          end
       end
     end
   end
diff --git a/actionview/lib/action_view/helpers/tags/collection_helpers.rb b/actionview/lib/action_view/helpers/tags/collection_helpers.rb
index fb51460c8e..e1ad11bff8 100644
--- a/actionview/lib/action_view/helpers/tags/collection_helpers.rb
+++ b/actionview/lib/action_view/helpers/tags/collection_helpers.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActionView
   module Helpers
     module Tags # :nodoc:
@@ -17,7 +19,7 @@ module ActionView
             @input_html_options = input_html_options
           end
 
-          def label(label_html_options={}, &block)
+          def label(label_html_options = {}, &block)
             html_options = @input_html_options.slice(:index, :namespace).merge(label_html_options)
             html_options[:for] ||= @input_html_options[:id] if @input_html_options[:id]
 
@@ -36,81 +38,81 @@ module ActionView
 
         private
 
-        def instantiate_builder(builder_class, item, value, text, html_options)
-          builder_class.new(@template_object, @object_name, @method_name, item,
-                            sanitize_attribute_name(value), text, value, html_options)
-        end
-
-        # Generate default options for collection helpers, such as :checked and
-        # :disabled.
-        def default_html_options_for_collection(item, value) #:nodoc:
-          html_options = @html_options.dup
-
-          [:checked, :selected, :disabled, :readonly].each do |option|
-            current_value = @options[option]
-            next if current_value.nil?
+          def instantiate_builder(builder_class, item, value, text, html_options)
+            builder_class.new(@template_object, @object_name, @method_name, item,
+                              sanitize_attribute_name(value), text, value, html_options)
+          end
 
-            accept = if current_value.respond_to?(:call)
-              current_value.call(item)
-            else
-              Array(current_value).map(&:to_s).include?(value.to_s)
+          # Generate default options for collection helpers, such as :checked and
+          # :disabled.
+          def default_html_options_for_collection(item, value)
+            html_options = @html_options.dup
+
+            [:checked, :selected, :disabled, :readonly].each do |option|
+              current_value = @options[option]
+              next if current_value.nil?
+
+              accept = if current_value.respond_to?(:call)
+                current_value.call(item)
+              else
+                Array(current_value).map(&:to_s).include?(value.to_s)
+              end
+
+              if accept
+                html_options[option] = true
+              elsif option == :checked
+                html_options[option] = false
+              end
             end
 
-            if accept
-              html_options[option] = true
-            elsif option == :checked
-              html_options[option] = false
-            end
+            html_options[:object] = @object
+            html_options
           end
 
-          html_options[:object] = @object
-          html_options
-        end
+          def sanitize_attribute_name(value)
+            "#{sanitized_method_name}_#{sanitized_value(value)}"
+          end
 
-        def sanitize_attribute_name(value) #:nodoc:
-          "#{sanitized_method_name}_#{sanitized_value(value)}"
-        end
+          def render_collection
+            @collection.map do |item|
+              value = value_for_collection(item, @value_method)
+              text  = value_for_collection(item, @text_method)
+              default_html_options = default_html_options_for_collection(item, value)
+              additional_html_options = option_html_attributes(item)
 
-        def render_collection #:nodoc:
-          @collection.map do |item|
-            value = value_for_collection(item, @value_method)
-            text  = value_for_collection(item, @text_method)
-            default_html_options = default_html_options_for_collection(item, value)
-            additional_html_options = option_html_attributes(item)
+              yield item, value, text, default_html_options.merge(additional_html_options)
+            end.join.html_safe
+          end
 
-            yield item, value, text, default_html_options.merge(additional_html_options)
-          end.join.html_safe
-        end
+          def render_collection_for(builder_class, &block)
+            options = @options.stringify_keys
+            rendered_collection = render_collection do |item, value, text, default_html_options|
+              builder = instantiate_builder(builder_class, item, value, text, default_html_options)
 
-        def render_collection_for(builder_class, &block) #:nodoc:
-          options = @options.stringify_keys
-          rendered_collection = render_collection do |item, value, text, default_html_options|
-            builder = instantiate_builder(builder_class, item, value, text, default_html_options)
+              if block_given?
+                @template_object.capture(builder, &block)
+              else
+                render_component(builder)
+              end
+            end
 
-            if block_given?
-              @template_object.capture(builder, &block)
+            # Prepend a hidden field to make sure something will be sent back to the
+            # server if all radio buttons are unchecked.
+            if options.fetch("include_hidden", true)
+              hidden_field + rendered_collection
             else
-              render_component(builder)
+              rendered_collection
             end
           end
 
-          # Prepend a hidden field to make sure something will be sent back to the
-          # server if all radio buttons are unchecked.
-          if options.fetch('include_hidden', true)
-            hidden_field + rendered_collection
-          else
-            rendered_collection
+          def hidden_field
+            hidden_name = @html_options[:name] || hidden_field_name
+            @template_object.hidden_field_tag(hidden_name, "", id: nil)
           end
-        end
 
-        def hidden_field #:nodoc:
-          hidden_name = @html_options[:name] || hidden_field_name
-          @template_object.hidden_field_tag(hidden_name, "", id: nil)
-        end
-
-        def hidden_field_name #:nodoc:
-          "#{tag_name(false, @options[:index])}"
-        end
+          def hidden_field_name
+            "#{tag_name(false, @options[:index])}"
+          end
       end
     end
   end
diff --git a/actionview/lib/action_view/helpers/tags/collection_radio_buttons.rb b/actionview/lib/action_view/helpers/tags/collection_radio_buttons.rb
index 21aaf122f8..16d37134e5 100644
--- a/actionview/lib/action_view/helpers/tags/collection_radio_buttons.rb
+++ b/actionview/lib/action_view/helpers/tags/collection_radio_buttons.rb
@@ -1,4 +1,6 @@
-require 'action_view/helpers/tags/collection_helpers'
+# frozen_string_literal: true
+
+require "action_view/helpers/tags/collection_helpers"
 
 module ActionView
   module Helpers
@@ -7,8 +9,9 @@ module ActionView
         include CollectionHelpers
 
         class RadioButtonBuilder < Builder # :nodoc:
-          def radio_button(extra_html_options={})
+          def radio_button(extra_html_options = {})
             html_options = extra_html_options.merge(@input_html_options)
+            html_options[:skip_default_ids] = false
             @template_object.radio_button(@object_name, @method_name, @value, html_options)
           end
         end
diff --git a/actionview/lib/action_view/helpers/tags/collection_select.rb b/actionview/lib/action_view/helpers/tags/collection_select.rb
index 6cb2b2e0d3..6a3af1b256 100644
--- a/actionview/lib/action_view/helpers/tags/collection_select.rb
+++ b/actionview/lib/action_view/helpers/tags/collection_select.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActionView
   module Helpers
     module Tags # :nodoc:
@@ -13,8 +15,8 @@ module ActionView
 
         def render
           option_tags_options = {
-            :selected => @options.fetch(:selected) { value(@object) },
-            :disabled => @options[:disabled]
+            selected: @options.fetch(:selected) { value },
+            disabled: @options[:disabled]
           }
 
           select_content_tag(
diff --git a/actionview/lib/action_view/helpers/tags/color_field.rb b/actionview/lib/action_view/helpers/tags/color_field.rb
index b4bbe92746..c5f0bb6bbb 100644
--- a/actionview/lib/action_view/helpers/tags/color_field.rb
+++ b/actionview/lib/action_view/helpers/tags/color_field.rb
@@ -1,10 +1,12 @@
+# frozen_string_literal: true
+
 module ActionView
   module Helpers
     module Tags # :nodoc:
       class ColorField < TextField # :nodoc:
         def render
           options = @options.stringify_keys
-          options["value"] ||= validate_color_string(value(object))
+          options["value"] ||= validate_color_string(value)
           @options = options
           super
         end
diff --git a/actionview/lib/action_view/helpers/tags/date_field.rb b/actionview/lib/action_view/helpers/tags/date_field.rb
index c22be0db29..b17a907651 100644
--- a/actionview/lib/action_view/helpers/tags/date_field.rb
+++ b/actionview/lib/action_view/helpers/tags/date_field.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActionView
   module Helpers
     module Tags # :nodoc:
diff --git a/actionview/lib/action_view/helpers/tags/date_select.rb b/actionview/lib/action_view/helpers/tags/date_select.rb
index 0c4ac40070..fe4e3914d7 100644
--- a/actionview/lib/action_view/helpers/tags/date_select.rb
+++ b/actionview/lib/action_view/helpers/tags/date_select.rb
@@ -1,4 +1,6 @@
-require 'active_support/core_ext/time/calculations'
+# frozen_string_literal: true
+
+require "active_support/core_ext/time/calculations"
 
 module ActionView
   module Helpers
@@ -16,56 +18,56 @@ module ActionView
 
         class << self
           def select_type
-            @select_type ||= self.name.split("::").last.sub("Select", "").downcase
+            @select_type ||= name.split("::").last.sub("Select", "").downcase
           end
         end
 
         private
 
-        def select_type
-          self.class.select_type
-        end
+          def select_type
+            self.class.select_type
+          end
 
-        def datetime_selector(options, html_options)
-          datetime = options.fetch(:selected) { value(object) || default_datetime(options) }
-          @auto_index ||= nil
+          def datetime_selector(options, html_options)
+            datetime = options.fetch(:selected) { value || default_datetime(options) }
+            @auto_index ||= nil
 
-          options = options.dup
-          options[:field_name]           = @method_name
-          options[:include_position]     = true
-          options[:prefix]             ||= @object_name
-          options[:index]                = @auto_index if @auto_index && !options.has_key?(:index)
+            options = options.dup
+            options[:field_name]           = @method_name
+            options[:include_position]     = true
+            options[:prefix]             ||= @object_name
+            options[:index]                = @auto_index if @auto_index && !options.has_key?(:index)
 
-          DateTimeSelector.new(datetime, options, html_options)
-        end
+            DateTimeSelector.new(datetime, options, html_options)
+          end
 
-        def default_datetime(options)
-          return if options[:include_blank] || options[:prompt]
+          def default_datetime(options)
+            return if options[:include_blank] || options[:prompt]
 
-          case options[:default]
-          when nil
-            Time.current
-          when Date, Time
-            options[:default]
-          else
-            default = options[:default].dup
+            case options[:default]
+            when nil
+              Time.current
+            when Date, Time
+              options[:default]
+            else
+              default = options[:default].dup
 
-            # Rename :minute and :second to :min and :sec
-            default[:min] ||= default[:minute]
-            default[:sec] ||= default[:second]
+              # Rename :minute and :second to :min and :sec
+              default[:min] ||= default[:minute]
+              default[:sec] ||= default[:second]
 
-            time = Time.current
+              time = Time.current
 
-            [:year, :month, :day, :hour, :min, :sec].each do |key|
-              default[key] ||= time.send(key)
-            end
+              [:year, :month, :day, :hour, :min, :sec].each do |key|
+                default[key] ||= time.send(key)
+              end
 
-            Time.utc(
-              default[:year], default[:month], default[:day],
-              default[:hour], default[:min], default[:sec]
-            )
+              Time.utc(
+                default[:year], default[:month], default[:day],
+                default[:hour], default[:min], default[:sec]
+              )
+            end
           end
-        end
       end
     end
   end
diff --git a/actionview/lib/action_view/helpers/tags/datetime_field.rb b/actionview/lib/action_view/helpers/tags/datetime_field.rb
index b2cee9d198..5d9b639b1b 100644
--- a/actionview/lib/action_view/helpers/tags/datetime_field.rb
+++ b/actionview/lib/action_view/helpers/tags/datetime_field.rb
@@ -1,10 +1,12 @@
+# frozen_string_literal: true
+
 module ActionView
   module Helpers
     module Tags # :nodoc:
       class DatetimeField < TextField # :nodoc:
         def render
           options = @options.stringify_keys
-          options["value"] ||= format_date(value(object))
+          options["value"] ||= format_date(value)
           options["min"] = format_date(datetime_value(options["min"]))
           options["max"] = format_date(datetime_value(options["max"]))
           @options = options
@@ -14,7 +16,7 @@ module ActionView
         private
 
           def format_date(value)
-            value.try(:strftime, "%Y-%m-%dT%T.%L%z")
+            raise NotImplementedError
           end
 
           def datetime_value(value)
diff --git a/actionview/lib/action_view/helpers/tags/datetime_local_field.rb b/actionview/lib/action_view/helpers/tags/datetime_local_field.rb
index b4a74185d1..d8f8fd00d1 100644
--- a/actionview/lib/action_view/helpers/tags/datetime_local_field.rb
+++ b/actionview/lib/action_view/helpers/tags/datetime_local_field.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActionView
   module Helpers
     module Tags # :nodoc:
diff --git a/actionview/lib/action_view/helpers/tags/datetime_select.rb b/actionview/lib/action_view/helpers/tags/datetime_select.rb
index 563de1840e..dc5570931d 100644
--- a/actionview/lib/action_view/helpers/tags/datetime_select.rb
+++ b/actionview/lib/action_view/helpers/tags/datetime_select.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActionView
   module Helpers
     module Tags # :nodoc:
diff --git a/actionview/lib/action_view/helpers/tags/email_field.rb b/actionview/lib/action_view/helpers/tags/email_field.rb
index 7ce3ccb9bf..0c3b9224fa 100644
--- a/actionview/lib/action_view/helpers/tags/email_field.rb
+++ b/actionview/lib/action_view/helpers/tags/email_field.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActionView
   module Helpers
     module Tags # :nodoc:
diff --git a/actionview/lib/action_view/helpers/tags/file_field.rb b/actionview/lib/action_view/helpers/tags/file_field.rb
index e6a1d9c62d..0b1d9bb778 100644
--- a/actionview/lib/action_view/helpers/tags/file_field.rb
+++ b/actionview/lib/action_view/helpers/tags/file_field.rb
@@ -1,22 +1,9 @@
+# frozen_string_literal: true
+
 module ActionView
   module Helpers
     module Tags # :nodoc:
       class FileField < TextField # :nodoc:
-
-        def render
-          options = @options.stringify_keys
-
-          if options.fetch("include_hidden", true)
-            add_default_name_and_id(options)
-            options[:type] = "file"
-            tag("input", name: options["name"], type: "hidden", value: "") + tag("input", options)
-          else
-            options.delete("include_hidden")
-            @options = options
-
-            super
-          end
-        end
       end
     end
   end
diff --git a/actionview/lib/action_view/helpers/tags/grouped_collection_select.rb b/actionview/lib/action_view/helpers/tags/grouped_collection_select.rb
index 2ed4712dac..f24cb4beea 100644
--- a/actionview/lib/action_view/helpers/tags/grouped_collection_select.rb
+++ b/actionview/lib/action_view/helpers/tags/grouped_collection_select.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActionView
   module Helpers
     module Tags # :nodoc:
@@ -15,8 +17,8 @@ module ActionView
 
         def render
           option_tags_options = {
-            :selected => @options.fetch(:selected) { value(@object) },
-            :disabled => @options[:disabled]
+            selected: @options.fetch(:selected) { value },
+            disabled: @options[:disabled]
           }
 
           select_content_tag(
diff --git a/actionview/lib/action_view/helpers/tags/hidden_field.rb b/actionview/lib/action_view/helpers/tags/hidden_field.rb
index c3757c2461..e014bd3aef 100644
--- a/actionview/lib/action_view/helpers/tags/hidden_field.rb
+++ b/actionview/lib/action_view/helpers/tags/hidden_field.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActionView
   module Helpers
     module Tags # :nodoc:
diff --git a/actionview/lib/action_view/helpers/tags/label.rb b/actionview/lib/action_view/helpers/tags/label.rb
index b31d5fda66..02bd099784 100644
--- a/actionview/lib/action_view/helpers/tags/label.rb
+++ b/actionview/lib/action_view/helpers/tags/label.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActionView
   module Helpers
     module Tags # :nodoc:
diff --git a/actionview/lib/action_view/helpers/tags/month_field.rb b/actionview/lib/action_view/helpers/tags/month_field.rb
index 4c0fb846ee..93b2bf11f0 100644
--- a/actionview/lib/action_view/helpers/tags/month_field.rb
+++ b/actionview/lib/action_view/helpers/tags/month_field.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActionView
   module Helpers
     module Tags # :nodoc:
diff --git a/actionview/lib/action_view/helpers/tags/number_field.rb b/actionview/lib/action_view/helpers/tags/number_field.rb
index 4f95b1b4de..41c696423c 100644
--- a/actionview/lib/action_view/helpers/tags/number_field.rb
+++ b/actionview/lib/action_view/helpers/tags/number_field.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActionView
   module Helpers
     module Tags # :nodoc:
diff --git a/actionview/lib/action_view/helpers/tags/password_field.rb b/actionview/lib/action_view/helpers/tags/password_field.rb
index 6099fa6f19..9f10f5236e 100644
--- a/actionview/lib/action_view/helpers/tags/password_field.rb
+++ b/actionview/lib/action_view/helpers/tags/password_field.rb
@@ -1,9 +1,11 @@
+# frozen_string_literal: true
+
 module ActionView
   module Helpers
     module Tags # :nodoc:
       class PasswordField < TextField # :nodoc:
         def render
-          @options = {:value => nil}.merge!(@options)
+          @options = { value: nil }.merge!(@options)
           super
         end
       end
diff --git a/actionview/lib/action_view/helpers/tags/placeholderable.rb b/actionview/lib/action_view/helpers/tags/placeholderable.rb
index cf7b117614..e9f7601e57 100644
--- a/actionview/lib/action_view/helpers/tags/placeholderable.rb
+++ b/actionview/lib/action_view/helpers/tags/placeholderable.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActionView
   module Helpers
     module Tags # :nodoc:
diff --git a/actionview/lib/action_view/helpers/tags/radio_button.rb b/actionview/lib/action_view/helpers/tags/radio_button.rb
index 4849c537a5..621db2b1b5 100644
--- a/actionview/lib/action_view/helpers/tags/radio_button.rb
+++ b/actionview/lib/action_view/helpers/tags/radio_button.rb
@@ -1,4 +1,6 @@
-require 'action_view/helpers/tags/checkable'
+# frozen_string_literal: true
+
+require "action_view/helpers/tags/checkable"
 
 module ActionView
   module Helpers
@@ -15,16 +17,16 @@ module ActionView
           options = @options.stringify_keys
           options["type"]     = "radio"
           options["value"]    = @tag_value
-          options["checked"] = "checked" if input_checked?(object, options)
+          options["checked"] = "checked" if input_checked?(options)
           add_default_name_and_id_for_value(@tag_value, options)
           tag("input", options)
         end
 
         private
 
-        def checked?(value)
-          value.to_s == @tag_value.to_s
-        end
+          def checked?(value)
+            value.to_s == @tag_value.to_s
+          end
       end
     end
   end
diff --git a/actionview/lib/action_view/helpers/tags/range_field.rb b/actionview/lib/action_view/helpers/tags/range_field.rb
index f98ae88043..66d1bbac5b 100644
--- a/actionview/lib/action_view/helpers/tags/range_field.rb
+++ b/actionview/lib/action_view/helpers/tags/range_field.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActionView
   module Helpers
     module Tags # :nodoc:
diff --git a/actionview/lib/action_view/helpers/tags/search_field.rb b/actionview/lib/action_view/helpers/tags/search_field.rb
index a848aeabfa..f209348904 100644
--- a/actionview/lib/action_view/helpers/tags/search_field.rb
+++ b/actionview/lib/action_view/helpers/tags/search_field.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActionView
   module Helpers
     module Tags # :nodoc:
diff --git a/actionview/lib/action_view/helpers/tags/select.rb b/actionview/lib/action_view/helpers/tags/select.rb
index 180900cc8d..345484ba92 100644
--- a/actionview/lib/action_view/helpers/tags/select.rb
+++ b/actionview/lib/action_view/helpers/tags/select.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActionView
   module Helpers
     module Tags # :nodoc:
@@ -6,15 +8,15 @@ module ActionView
           @choices = block_given? ? template_object.capture { yield || "" } : choices
           @choices = @choices.to_a if @choices.is_a?(Range)
 
-          @html_options = html_options
+          @html_options = html_options.except(:skip_default_ids, :allow_method_names_outside_object)
 
           super(object_name, method_name, template_object, options)
         end
 
         def render
           option_tags_options = {
-            :selected => @options.fetch(:selected) { value(@object) },
-            :disabled => @options[:disabled]
+            selected: @options.fetch(:selected) { value },
+            disabled: @options[:disabled]
           }
 
           option_tags = if grouped_choices?
@@ -28,13 +30,13 @@ module ActionView
 
         private
 
-        # Grouped choices look like this:
-        #
-        #   [nil, []]
-        #   { nil => [] }
-        def grouped_choices?
-          !@choices.empty? && @choices.first.respond_to?(:last) && Array === @choices.first.last
-        end
+          # Grouped choices look like this:
+          #
+          #   [nil, []]
+          #   { nil => [] }
+          def grouped_choices?
+            !@choices.blank? && @choices.first.respond_to?(:last) && Array === @choices.first.last
+          end
       end
     end
   end
diff --git a/actionview/lib/action_view/helpers/tags/tel_field.rb b/actionview/lib/action_view/helpers/tags/tel_field.rb
index 987bb9e67a..ab1caaac48 100644
--- a/actionview/lib/action_view/helpers/tags/tel_field.rb
+++ b/actionview/lib/action_view/helpers/tags/tel_field.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActionView
   module Helpers
     module Tags # :nodoc:
diff --git a/actionview/lib/action_view/helpers/tags/text_area.rb b/actionview/lib/action_view/helpers/tags/text_area.rb
index 69038c1498..4519082ff6 100644
--- a/actionview/lib/action_view/helpers/tags/text_area.rb
+++ b/actionview/lib/action_view/helpers/tags/text_area.rb
@@ -1,4 +1,6 @@
-require 'action_view/helpers/tags/placeholderable'
+# frozen_string_literal: true
+
+require "action_view/helpers/tags/placeholderable"
 
 module ActionView
   module Helpers
@@ -14,7 +16,7 @@ module ActionView
             options["cols"], options["rows"] = size.split("x") if size.respond_to?(:split)
           end
 
-          content_tag("textarea", options.delete("value") { value_before_type_cast(object) }, options)
+          content_tag("textarea", options.delete("value") { value_before_type_cast }, options)
         end
       end
     end
diff --git a/actionview/lib/action_view/helpers/tags/text_field.rb b/actionview/lib/action_view/helpers/tags/text_field.rb
index 5c576a20ca..d92967e212 100644
--- a/actionview/lib/action_view/helpers/tags/text_field.rb
+++ b/actionview/lib/action_view/helpers/tags/text_field.rb
@@ -1,4 +1,6 @@
-require 'action_view/helpers/tags/placeholderable'
+# frozen_string_literal: true
+
+require "action_view/helpers/tags/placeholderable"
 
 module ActionView
   module Helpers
@@ -10,22 +12,22 @@ module ActionView
           options = @options.stringify_keys
           options["size"] = options["maxlength"] unless options.key?("size")
           options["type"] ||= field_type
-          options["value"] = options.fetch("value") { value_before_type_cast(object) } unless field_type == "file"
+          options["value"] = options.fetch("value") { value_before_type_cast } unless field_type == "file"
           add_default_name_and_id(options)
           tag("input", options)
         end
 
         class << self
           def field_type
-            @field_type ||= self.name.split("::").last.sub("Field", "").downcase
+            @field_type ||= name.split("::").last.sub("Field", "").downcase
           end
         end
 
         private
 
-        def field_type
-          self.class.field_type
-        end
+          def field_type
+            self.class.field_type
+          end
       end
     end
   end
diff --git a/actionview/lib/action_view/helpers/tags/time_field.rb b/actionview/lib/action_view/helpers/tags/time_field.rb
index 0e90a3aed7..9384a83a3e 100644
--- a/actionview/lib/action_view/helpers/tags/time_field.rb
+++ b/actionview/lib/action_view/helpers/tags/time_field.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActionView
   module Helpers
     module Tags # :nodoc:
diff --git a/actionview/lib/action_view/helpers/tags/time_select.rb b/actionview/lib/action_view/helpers/tags/time_select.rb
index 0b06311d25..ba3dcb64e3 100644
--- a/actionview/lib/action_view/helpers/tags/time_select.rb
+++ b/actionview/lib/action_view/helpers/tags/time_select.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActionView
   module Helpers
     module Tags # :nodoc:
diff --git a/actionview/lib/action_view/helpers/tags/time_zone_select.rb b/actionview/lib/action_view/helpers/tags/time_zone_select.rb
index 80d165ec7e..1d06096096 100644
--- a/actionview/lib/action_view/helpers/tags/time_zone_select.rb
+++ b/actionview/lib/action_view/helpers/tags/time_zone_select.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActionView
   module Helpers
     module Tags # :nodoc:
@@ -11,7 +13,7 @@ module ActionView
 
         def render
           select_content_tag(
-            time_zone_options_for_select(value(@object) || @options[:default], @priority_zones, @options[:model] || ActiveSupport::TimeZone), @options, @html_options
+            time_zone_options_for_select(value || @options[:default], @priority_zones, @options[:model] || ActiveSupport::TimeZone), @options, @html_options
           )
         end
       end
diff --git a/actionview/lib/action_view/helpers/tags/translator.rb b/actionview/lib/action_view/helpers/tags/translator.rb
index 8b6655481d..fcf96d2c9c 100644
--- a/actionview/lib/action_view/helpers/tags/translator.rb
+++ b/actionview/lib/action_view/helpers/tags/translator.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActionView
   module Helpers
     module Tags # :nodoc:
@@ -14,26 +16,28 @@ module ActionView
           translated_attribute || human_attribute_name
         end
 
+        # TODO Change this to private once we've dropped Ruby 2.2 support.
+        # Workaround for Ruby 2.2 "private attribute?" warning.
         protected
 
-        attr_reader :object_name, :method_and_value, :scope, :model
+          attr_reader :object_name, :method_and_value, :scope, :model
 
         private
 
-        def i18n_default
-          if model
-            key = model.model_name.i18n_key
-            ["#{key}.#{method_and_value}".to_sym, ""]
-          else
-            ""
+          def i18n_default
+            if model
+              key = model.model_name.i18n_key
+              ["#{key}.#{method_and_value}".to_sym, ""]
+            else
+              ""
+            end
           end
-        end
 
-        def human_attribute_name
-          if model && model.class.respond_to?(:human_attribute_name)
-            model.class.human_attribute_name(method_and_value)
+          def human_attribute_name
+            if model && model.class.respond_to?(:human_attribute_name)
+              model.class.human_attribute_name(method_and_value)
+            end
           end
-        end
       end
     end
   end
diff --git a/actionview/lib/action_view/helpers/tags/url_field.rb b/actionview/lib/action_view/helpers/tags/url_field.rb
index d76340178d..395fec67e7 100644
--- a/actionview/lib/action_view/helpers/tags/url_field.rb
+++ b/actionview/lib/action_view/helpers/tags/url_field.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActionView
   module Helpers
     module Tags # :nodoc:
diff --git a/actionview/lib/action_view/helpers/tags/week_field.rb b/actionview/lib/action_view/helpers/tags/week_field.rb
index 835d1667d7..572535d1d6 100644
--- a/actionview/lib/action_view/helpers/tags/week_field.rb
+++ b/actionview/lib/action_view/helpers/tags/week_field.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActionView
   module Helpers
     module Tags # :nodoc:
diff --git a/actionview/lib/action_view/helpers/text_helper.rb b/actionview/lib/action_view/helpers/text_helper.rb
index 58ce042f12..84d38aa416 100644
--- a/actionview/lib/action_view/helpers/text_helper.rb
+++ b/actionview/lib/action_view/helpers/text_helper.rb
@@ -1,5 +1,7 @@
-require 'active_support/core_ext/string/filters'
-require 'active_support/core_ext/array/extract_options'
+# frozen_string_literal: true
+
+require "active_support/core_ext/string/filters"
+require "active_support/core_ext/array/extract_options"
 
 module ActionView
   # = Action View Text Helpers
@@ -135,7 +137,7 @@ module ActionView
         else
           match = Array(phrases).map do |p|
             Regexp === p ? p.to_s : Regexp.escape(p)
-          end.join('|')
+          end.join("|")
 
           if block_given?
             text.gsub(/(#{match})(?![^<]*?>)/i) { |found| yield found }
@@ -151,7 +153,7 @@ module ActionView
       # defined in <tt>:radius</tt> (which defaults to 100). If the excerpt radius overflows the beginning or end of the +text+,
       # then the <tt>:omission</tt> option (which defaults to "...") will be prepended/appended accordingly. Use the
       # <tt>:separator</tt> option to choose the delimitation. The resulting string will be stripped in any case. If the +phrase+
-      # isn't found, nil is returned.
+      # isn't found, +nil+ is returned.
       #
       #   excerpt('This is an example', 'an', radius: 5)
       #   # => ...s is an exam...
@@ -187,7 +189,7 @@ module ActionView
         unless separator.empty?
           text.split(separator).each do |value|
             if value.match(regex)
-              regex = phrase = value
+              phrase = value
               break
             end
           end
@@ -225,14 +227,7 @@ module ActionView
       #
       #   pluralize(2, 'Person', locale: :de)
       #   # => 2 Personen
-      def pluralize(count, singular, deprecated_plural = nil, plural: nil, locale: I18n.locale)
-        if deprecated_plural
-          ActiveSupport::Deprecation.warn("Passing plural as a positional argument " \
-            "is deprecated and will be removed in Rails 5.1. Use e.g. " \
-            "pluralize(1, 'person', plural: 'people') instead.")
-          plural ||= deprecated_plural
-        end
-
+      def pluralize(count, singular, plural_arg = nil, plural: plural_arg, locale: I18n.locale)
         word = if (count == 1 || count =~ /^1(\.0+)?$/)
           singular
         else
@@ -269,10 +264,11 @@ module ActionView
       end
 
       # Returns +text+ transformed into HTML using simple formatting rules.
-      # Two or more consecutive newlines(<tt>\n\n</tt>) are considered as a
-      # paragraph and wrapped in <tt><p></tt> tags. One newline (<tt>\n</tt>) is
-      # considered as a linebreak and a <tt><br /></tt> tag is appended. This
-      # method does not remove the newlines from the +text+.
+      # Two or more consecutive newlines(<tt>\n\n</tt> or <tt>\r\n\r\n</tt>) are
+      # considered a paragraph and wrapped in <tt><p></tt> tags. One newline
+      # (<tt>\n</tt> or <tt>\r\n</tt>) is considered a linebreak and a
+      # <tt><br /></tt> tag is appended. This method does not remove the
+      # newlines from the +text+.
       #
       # You can pass any HTML attributes into <tt>html_options</tt>. These
       # will be added to all created paragraphs.
@@ -357,7 +353,7 @@ module ActionView
       #  <% end %>
       def cycle(first_value, *values)
         options = values.extract_options!
-        name = options.fetch(:name, 'default')
+        name = options.fetch(:name, "default")
 
         values.unshift(*first_value)
 
@@ -426,22 +422,22 @@ module ActionView
         def to_s
           value = @values[@index].to_s
           @index = next_index
-          return value
+          value
         end
 
         private
 
-        def next_index
-          step_index(1)
-        end
+          def next_index
+            step_index(1)
+          end
 
-        def previous_index
-          step_index(-1)
-        end
+          def previous_index
+            step_index(-1)
+          end
 
-        def step_index(n)
-          (@index + n) % @values.size
-        end
+          def step_index(n)
+            (@index + n) % @values.size
+          end
       end
 
       private
@@ -450,7 +446,7 @@ module ActionView
         # uses an instance variable of ActionView::Base.
         def get_cycle(name)
           @_cycles = Hash.new unless defined?(@_cycles)
-          return @_cycles[name]
+          @_cycles[name]
         end
 
         def set_cycle(name, cycle_object)
diff --git a/actionview/lib/action_view/helpers/translation_helper.rb b/actionview/lib/action_view/helpers/translation_helper.rb
index 152e1b1211..1860bc4732 100644
--- a/actionview/lib/action_view/helpers/translation_helper.rb
+++ b/actionview/lib/action_view/helpers/translation_helper.rb
@@ -1,18 +1,19 @@
-require 'action_view/helpers/tag_helper'
-require 'active_support/core_ext/string/access'
-require 'i18n/exceptions'
+# frozen_string_literal: true
+
+require "action_view/helpers/tag_helper"
+require "active_support/core_ext/string/access"
+require "i18n/exceptions"
 
 module ActionView
   # = Action View Translation Helpers
-  module Helpers
+  module Helpers #:nodoc:
     module TranslationHelper
       extend ActiveSupport::Concern
 
       include TagHelper
 
       included do
-        mattr_accessor :debug_missing_translation
-        self.debug_missing_translation = true
+        mattr_accessor :debug_missing_translation, default: true
       end
 
       # Delegates to <tt>I18n#translate</tt> but also performs three additional
@@ -96,16 +97,16 @@ module ActionView
           raise e if raise_error
 
           keys = I18n.normalize_keys(e.locale, e.key, e.options[:scope])
-          title = "translation missing: #{keys.join('.')}"
+          title = "translation missing: #{keys.join('.')}".dup
 
           interpolations = options.except(:default, :scope)
           if interpolations.any?
-            title << ", " << interpolations.map { |k, v| "#{k}: #{ERB::Util.html_escape(v)}" }.join(', ')
+            title << ", " << interpolations.map { |k, v| "#{k}: #{ERB::Util.html_escape(v)}" }.join(", ")
           end
 
           return title unless ActionView::Base.debug_missing_translation
 
-          content_tag('span', keys.last.to_s.titleize, class: 'translation_missing', title: title)
+          content_tag("span", keys.last.to_s.titleize, class: "translation_missing", title: title)
         end
       end
       alias :t :translate
@@ -133,7 +134,7 @@ module ActionView
         end
 
         def html_safe_translation_key?(key)
-          key.to_s =~ /(\b|_|\.)html$/
+          /(\b|_|\.)html$/.match?(key.to_s)
         end
     end
   end
diff --git a/actionview/lib/action_view/helpers/url_helper.rb b/actionview/lib/action_view/helpers/url_helper.rb
index 11c7daf4da..889562c478 100644
--- a/actionview/lib/action_view/helpers/url_helper.rb
+++ b/actionview/lib/action_view/helpers/url_helper.rb
@@ -1,7 +1,9 @@
-require 'action_view/helpers/javascript_helper'
-require 'active_support/core_ext/array/access'
-require 'active_support/core_ext/hash/keys'
-require 'active_support/core_ext/string/output_safety'
+# frozen_string_literal: true
+
+require "action_view/helpers/javascript_helper"
+require "active_support/core_ext/array/access"
+require "active_support/core_ext/hash/keys"
+require "active_support/core_ext/string/output_safety"
 
 module ActionView
   # = Action View URL Helpers
@@ -35,20 +37,20 @@ module ActionView
         when :back
           _back_url
         else
-          raise ArgumentError, "arguments passed to url_for can't be handled. Please require " +
+          raise ArgumentError, "arguments passed to url_for can't be handled. Please require " \
                                "routes or provide your own implementation"
         end
       end
 
       def _back_url # :nodoc:
-        _filtered_referrer || 'javascript:history.back()'
+        _filtered_referrer || "javascript:history.back()"
       end
       protected :_back_url
 
       def _filtered_referrer # :nodoc:
         if controller.respond_to?(:request)
           referrer = controller.request.env["HTTP_REFERER"]
-          if referrer && URI(referrer).scheme != 'javascript'
+          if referrer && URI(referrer).scheme != "javascript"
             referrer
           end
         end
@@ -105,10 +107,9 @@ module ActionView
       #   driver to prompt with the question specified (in this case, the
       #   resulting text would be <tt>question?</tt>. If the user accepts, the
       #   link is processed normally, otherwise no action is taken.
-      # * <tt>:disable_with</tt> - Value of this parameter will be
-      #   used as the value for a disabled version of the submit
-      #   button when the form is submitted. This feature is provided
-      #   by the unobtrusive JavaScript driver.
+      # * <tt>:disable_with</tt> - Value of this parameter will be used as the
+      #   name for a disabled version of the link. This feature is provided by
+      #   the unobtrusive JavaScript driver.
       #
       # ==== Examples
       # Because it relies on +url_for+, +link_to+ supports both older-style controller/action/id arguments
@@ -138,6 +139,11 @@ module ActionView
       #   link_to "Profiles", controller: "profiles"
       #   # => <a href="/profiles">Profiles</a>
       #
+      # When name is +nil+ the href is presented instead
+      #
+      #   link_to nil, "http://example.com"
+      #   # => <a href="http://www.example.com">http://www.example.com</a>
+      #
       # You can use a block as well if your link target is hard to fit into the name parameter. ERB example:
       #
       #   <%= link_to(@profile) do %>
@@ -298,34 +304,34 @@ module ActionView
         html_options = html_options.stringify_keys
 
         url    = options.is_a?(String) ? options : url_for(options)
-        remote = html_options.delete('remote')
-        params = html_options.delete('params')
+        remote = html_options.delete("remote")
+        params = html_options.delete("params")
 
-        method     = html_options.delete('method').to_s
-        method_tag = BUTTON_TAG_METHOD_VERBS.include?(method) ? method_tag(method) : ''.freeze.html_safe
+        method     = html_options.delete("method").to_s
+        method_tag = BUTTON_TAG_METHOD_VERBS.include?(method) ? method_tag(method) : "".freeze.html_safe
 
-        form_method  = method == 'get' ? 'get' : 'post'
-        form_options = html_options.delete('form') || {}
-        form_options[:class] ||= html_options.delete('form_class') || 'button_to'
+        form_method  = method == "get" ? "get" : "post"
+        form_options = html_options.delete("form") || {}
+        form_options[:class] ||= html_options.delete("form_class") || "button_to"
         form_options[:method] = form_method
         form_options[:action] = url
         form_options[:'data-remote'] = true if remote
 
-        request_token_tag = if form_method == 'post'
-          request_method = method.empty? ? 'post' : method
+        request_token_tag = if form_method == "post"
+          request_method = method.empty? ? "post" : method
           token_tag(nil, form_options: { action: url, method: request_method })
         else
-          ''.freeze
+          "".freeze
         end
 
         html_options = convert_options_to_data_attributes(options, html_options)
-        html_options['type'] = 'submit'
+        html_options["type"] = "submit"
 
         button = if block_given?
-          content_tag('button', html_options, &block)
+          content_tag("button", html_options, &block)
         else
-          html_options['value'] = name || url
-          tag('input', html_options)
+          html_options["value"] = name || url
+          tag("input", html_options)
         end
 
         inner_tags = method_tag.safe_concat(button).safe_concat(request_token_tag)
@@ -334,7 +340,7 @@ module ActionView
             inner_tags.safe_concat tag(:input, type: "hidden", name: param[:name], value: param[:value])
           end
         end
-        content_tag('form', inner_tags, form_options)
+        content_tag("form", inner_tags, form_options)
       end
 
       # Creates a link tag of the given +name+ using a URL created by the set of
@@ -481,7 +487,7 @@ module ActionView
           option = html_options.delete(item).presence || next
           "#{item.dasherize}=#{ERB::Util.url_encode(option)}"
         }.compact
-        extras = extras.empty? ? ''.freeze : '?' + extras.join('&')
+        extras = extras.empty? ? "".freeze : "?" + extras.join("&")
 
         encoded_email_address = ERB::Util.url_encode(email_address).gsub("%40", "@")
         html_options["href"] = "mailto:#{encoded_email_address}#{extras}"
@@ -518,6 +524,9 @@ module ActionView
       #   current_page?('http://www.example.com/shop/checkout')
       #   # => true
       #
+      #   current_page?('http://www.example.com/shop/checkout', check_parameters: true)
+      #   # => false
+      #
       #   current_page?('/shop/checkout')
       #   # => true
       #
@@ -531,7 +540,7 @@ module ActionView
       #
       # We can also pass in the symbol arguments instead of strings.
       #
-      def current_page?(options)
+      def current_page?(options, check_parameters: false)
         unless request
           raise "You cannot use helpers that need to determine the current " \
                 "page unless your view context provides a Request object " \
@@ -540,15 +549,22 @@ module ActionView
 
         return false unless request.get? || request.head?
 
+        check_parameters ||= options.is_a?(Hash) && options.delete(:check_parameters)
         url_string = URI.parser.unescape(url_for(options)).force_encoding(Encoding::BINARY)
 
         # We ignore any extra parameters in the request_uri if the
         # submitted url doesn't have any either. This lets the function
         # work with things like ?order=asc
-        request_uri = url_string.index("?") ? request.fullpath : request.path
+        # the behaviour can be disabled with check_parameters: true
+        request_uri = url_string.index("?") || check_parameters ? request.fullpath : request.path
         request_uri = URI.parser.unescape(request_uri).force_encoding(Encoding::BINARY)
 
-        if url_string =~ /^\w+:\/\//
+        if url_string.start_with?("/") && url_string != "/"
+          url_string.chomp!("/")
+          request_uri.chomp!("/")
+        end
+
+        if %r{^\w+://}.match?(url_string)
           url_string == "#{request.protocol}#{request.host_with_port}#{request_uri}"
         else
           url_string == request_uri
@@ -559,42 +575,59 @@ module ActionView
         def convert_options_to_data_attributes(options, html_options)
           if html_options
             html_options = html_options.stringify_keys
-            html_options['data-remote'] = 'true'.freeze if link_to_remote_options?(options) || link_to_remote_options?(html_options)
+            html_options["data-remote"] = "true".freeze if link_to_remote_options?(options) || link_to_remote_options?(html_options)
 
-            method  = html_options.delete('method'.freeze)
+            method = html_options.delete("method".freeze)
 
             add_method_to_attributes!(html_options, method) if method
 
             html_options
           else
-            link_to_remote_options?(options) ? {'data-remote' => 'true'.freeze} : {}
+            link_to_remote_options?(options) ? { "data-remote" => "true".freeze } : {}
           end
         end
 
         def link_to_remote_options?(options)
           if options.is_a?(Hash)
-            options.delete('remote'.freeze) || options.delete(:remote)
+            options.delete("remote".freeze) || options.delete(:remote)
           end
         end
 
         def add_method_to_attributes!(html_options, method)
-          if method && method.to_s.downcase != "get".freeze && html_options["rel".freeze] !~ /nofollow/
-            html_options["rel".freeze] = "#{html_options["rel".freeze]} nofollow".lstrip
+          if method_not_get_method?(method) && html_options["rel"] !~ /nofollow/
+            if html_options["rel"].blank?
+              html_options["rel"] = "nofollow"
+            else
+              html_options["rel"] = "#{html_options["rel"]} nofollow"
+            end
           end
-          html_options["data-method".freeze] = method
+          html_options["data-method"] = method
+        end
+
+        STRINGIFIED_COMMON_METHODS = {
+          get:    "get",
+          delete: "delete",
+          patch:  "patch",
+          post:   "post",
+          put:    "put",
+        }.freeze
+
+        def method_not_get_method?(method)
+          return false unless method
+          (STRINGIFIED_COMMON_METHODS[method] || method.to_s.downcase) != "get"
         end
 
-        def token_tag(token=nil, form_options: {})
+        def token_tag(token = nil, form_options: {})
           if token != false && protect_against_forgery?
             token ||= form_authenticity_token(form_options: form_options)
             tag(:input, type: "hidden", name: request_forgery_protection_token.to_s, value: token)
           else
-            ''.freeze
+            "".freeze
           end
         end
 
         def method_tag(method)
-          tag('input', type: 'hidden', name: '_method', value: method.to_s)
+          tag("input", type: "hidden", name: "_method", value: method.to_s)
         end
 
         # Returns an array of hashes each containing :name and :value keys
@@ -613,7 +646,13 @@ module ActionView
         #
         #   to_form_params({ name: 'Denmark' }, 'country')
         #   # => [{name: 'country[name]', value: 'Denmark'}]
-        def to_form_params(attribute, namespace = nil) # :nodoc:
+        def to_form_params(attribute, namespace = nil)
+          attribute = if attribute.respond_to?(:permitted?)
+            attribute.to_h
+          else
+            attribute
+          end
+
           params = []
           case attribute
           when Hash
diff --git a/actionview/lib/action_view/layouts.rb b/actionview/lib/action_view/layouts.rb
index a74a5e05f3..3e6d352c15 100644
--- a/actionview/lib/action_view/layouts.rb
+++ b/actionview/lib/action_view/layouts.rb
@@ -1,5 +1,7 @@
+# frozen_string_literal: true
+
 require "action_view/rendering"
-require "active_support/core_ext/module/remove_method"
+require "active_support/core_ext/module/redefine_method"
 
 module ActionView
   # Layouts reverse the common pattern of including shared headers and footers in many templates to isolate changes in
@@ -91,16 +93,16 @@ module ActionView
   #     layout false
   #
   # In these examples, we have three implicit lookup scenarios:
-  # * The BankController uses the "bank" layout.
-  # * The ExchangeController uses the "exchange" layout.
-  # * The CurrencyController inherits the layout from BankController.
+  # * The +BankController+ uses the "bank" layout.
+  # * The +ExchangeController+ uses the "exchange" layout.
+  # * The +CurrencyController+ inherits the layout from BankController.
   #
   # However, when a layout is explicitly set, the explicitly set layout wins:
-  # * The InformationController uses the "information" layout, explicitly set.
-  # * The TellerController also uses the "information" layout, because the parent explicitly set it.
-  # * The EmployeeController uses the "employee" layout, because it set the layout to nil, resetting the parent configuration.
-  # * The VaultController chooses a layout dynamically by calling the <tt>access_level_layout</tt> method.
-  # * The TillController does not use a layout at all.
+  # * The +InformationController+ uses the "information" layout, explicitly set.
+  # * The +TellerController+ also uses the "information" layout, because the parent explicitly set it.
+  # * The +EmployeeController+ uses the "employee" layout, because it set the layout to +nil+, resetting the parent configuration.
+  # * The +VaultController+ chooses a layout dynamically by calling the <tt>access_level_layout</tt> method.
+  # * The +TillController+ does not use a layout at all.
   #
   # == Types of layouts
   #
@@ -148,8 +150,8 @@ module ActionView
   # The template will be looked always in <tt>app/views/layouts/</tt> folder. But you can point
   # <tt>layouts</tt> folder direct also. <tt>layout "layouts/demo"</tt> is the same as <tt>layout "demo"</tt>.
   #
-  # Setting the layout to nil forces it to be looked up in the filesystem and fallbacks to the parent behavior if none exists.
-  # Setting it to nil is useful to re-enable template lookup overriding a previous configuration set in the parent:
+  # Setting the layout to +nil+ forces it to be looked up in the filesystem and fallbacks to the parent behavior if none exists.
+  # Setting it to +nil+ is useful to re-enable template lookup overriding a previous configuration set in the parent:
   #
   #     class ApplicationController < ActionController::Base
   #       layout "application"
@@ -204,9 +206,9 @@ module ActionView
     include ActionView::Rendering
 
     included do
-      class_attribute :_layout, :_layout_conditions, :instance_accessor => false
-      self._layout = nil
-      self._layout_conditions = {}
+      class_attribute :_layout, instance_accessor: false
+      class_attribute :_layout_conditions, instance_accessor: false, default: {}
+
       _write_layout_method
     end
 
@@ -223,36 +225,39 @@ module ActionView
       module LayoutConditions # :nodoc:
         private
 
-        # Determines whether the current action has a layout definition by
-        # checking the action name against the :only and :except conditions
-        # set by the <tt>layout</tt> method.
-        #
-        # ==== Returns
-        # * <tt>Boolean</tt> - True if the action has a layout definition, false otherwise.
-        def _conditional_layout?
-          return unless super
-
-          conditions = _layout_conditions
-
-          if only = conditions[:only]
-            only.include?(action_name)
-          elsif except = conditions[:except]
-            !except.include?(action_name)
-          else
-            true
+          # Determines whether the current action has a layout definition by
+          # checking the action name against the :only and :except conditions
+          # set by the <tt>layout</tt> method.
+          #
+          # ==== Returns
+          # * <tt>Boolean</tt> - True if the action has a layout definition, false otherwise.
+          def _conditional_layout?
+            return unless super
+
+            conditions = _layout_conditions
+
+            if only = conditions[:only]
+              only.include?(action_name)
+            elsif except = conditions[:except]
+              !except.include?(action_name)
+            else
+              true
+            end
           end
-        end
       end
 
       # Specify the layout to use for this class.
       #
       # If the specified layout is a:
       # String:: the String is the template name
-      # Symbol:: call the method specified by the symbol, which will return the template name
+      # Symbol:: call the method specified by the symbol
+      # Proc::   call the passed Proc
       # false::  There is no layout
       # true::   raise an ArgumentError
       # nil::    Force default layout behavior with inheritance
       #
+      # Return value of +Proc+ and +Symbol+ arguments should be +String+, +false+, +true+ or +nil+
+      # with the same meaning as described above.
       # ==== Parameters
       # * <tt>layout</tt> - The layout to use.
       #
@@ -262,7 +267,7 @@ module ActionView
       def layout(layout, conditions = {})
         include LayoutConditions unless conditions.empty?
 
-        conditions.each {|k, v| conditions[k] = Array(v).map(&:to_s) }
+        conditions.each { |k, v| conditions[k] = Array(v).map(&:to_s) }
         self._layout_conditions = conditions
 
         self._layout = layout
@@ -274,9 +279,9 @@ module ActionView
       # If a layout is not explicitly mentioned then look for a layout with the controller's name.
       # if nothing is found then try same procedure to find super class's layout.
       def _write_layout_method # :nodoc:
-        remove_possible_method(:_layout)
+        silence_redefinition_of_method(:_layout)
 
-        prefixes    = _implied_layout_name =~ /\blayouts/ ? [] : ["layouts"]
+        prefixes = /\blayouts/.match?(_implied_layout_name) ? [] : ["layouts"]
         default_behavior = "lookup_context.find_all('#{_implied_layout_name}', #{prefixes.inspect}, false, [], { formats: formats }).first || super"
         name_clause = if name
           default_behavior
@@ -286,7 +291,8 @@ module ActionView
           RUBY
         end
 
-        layout_definition = case _layout
+        layout_definition = \
+          case _layout
           when String
             _layout.inspect
           when Symbol
@@ -313,9 +319,9 @@ module ActionView
             raise ArgumentError, "Layouts must be specified as a String, Symbol, Proc, false, or nil"
           when nil
             name_clause
-        end
+          end
 
-        self.class_eval <<-RUBY, __FILE__, __LINE__ + 1
+        class_eval <<-RUBY, __FILE__, __LINE__ + 1
           def _layout(formats)
             if _conditional_layout?
               #{layout_definition}
@@ -329,14 +335,14 @@ module ActionView
 
       private
 
-      # If no layout is supplied, look for a template named the return
-      # value of this method.
-      #
-      # ==== Returns
-      # * <tt>String</tt> - A template name
-      def _implied_layout_name # :nodoc:
-        controller_path
-      end
+        # If no layout is supplied, look for a template named the return
+        # value of this method.
+        #
+        # ==== Returns
+        # * <tt>String</tt> - A template name
+        def _implied_layout_name
+          controller_path
+        end
     end
 
     def _normalize_options(options) # :nodoc:
@@ -400,11 +406,11 @@ module ActionView
     #
     # ==== Parameters
     # * <tt>formats</tt> - The formats accepted to this layout
-    # * <tt>require_layout</tt> - If set to true and layout is not found,
-    #   an +ArgumentError+ exception is raised (defaults to false)
+    # * <tt>require_layout</tt> - If set to +true+ and layout is not found,
+    #   an +ArgumentError+ exception is raised (defaults to +false+)
     #
     # ==== Returns
-    # * <tt>template</tt> - The template object for the default layout (or nil)
+    # * <tt>template</tt> - The template object for the default layout (or +nil+)
     def _default_layout(formats, require_layout = false)
       begin
         value = _layout(formats) if action_has_layout?
@@ -421,7 +427,7 @@ module ActionView
     end
 
     def _include_layout?(options)
-      (options.keys & [:body, :text, :plain, :html, :inline, :partial]).empty? || options.key?(:layout)
+      (options.keys & [:body, :plain, :html, :inline, :partial]).empty? || options.key?(:layout)
     end
   end
 end
diff --git a/actionview/lib/action_view/log_subscriber.rb b/actionview/lib/action_view/log_subscriber.rb
index 5a29c68214..d4ac77e10f 100644
--- a/actionview/lib/action_view/log_subscriber.rb
+++ b/actionview/lib/action_view/log_subscriber.rb
@@ -1,4 +1,6 @@
-require 'active_support/log_subscriber'
+# frozen_string_literal: true
+
+require "active_support/log_subscriber"
 
 module ActionView
   # = Action View Log Subscriber
@@ -14,15 +16,24 @@ module ActionView
 
     def render_template(event)
       info do
-        message = "  Rendered #{from_rails_root(event.payload[:identifier])}"
+        message = "  Rendered #{from_rails_root(event.payload[:identifier])}".dup
+        message << " within #{from_rails_root(event.payload[:layout])}" if event.payload[:layout]
+        message << " (#{event.duration.round(1)}ms)"
+      end
+    end
+
+    def render_partial(event)
+      info do
+        message = "  Rendered #{from_rails_root(event.payload[:identifier])}".dup
         message << " within #{from_rails_root(event.payload[:layout])}" if event.payload[:layout]
         message << " (#{event.duration.round(1)}ms)"
+        message << " #{cache_message(event.payload)}" unless event.payload[:cache_hit].nil?
+        message
       end
     end
-    alias :render_partial :render_template
 
     def render_collection(event)
-      identifier = event.payload[:identifier] || 'templates'
+      identifier = event.payload[:identifier] || "templates"
 
       info do
         "  Rendered collection of #{from_rails_root(identifier)}" \
@@ -42,20 +53,20 @@ module ActionView
       ActionView::Base.logger
     end
 
-  protected
+  private
 
-    EMPTY = ''
-    def from_rails_root(string)
+    EMPTY = ""
+    def from_rails_root(string) # :doc:
       string = string.sub(rails_root, EMPTY)
       string.sub!(VIEWS_PATTERN, EMPTY)
       string
     end
 
-    def rails_root
+    def rails_root # :doc:
       @root ||= "#{Rails.root}/"
     end
 
-    def render_count(payload)
+    def render_count(payload) # :doc:
       if payload[:cache_hits]
         "[#{payload[:cache_hits]} / #{payload[:count]} cache hits]"
       else
@@ -63,11 +74,18 @@ module ActionView
       end
     end
 
-  private
+    def cache_message(payload) # :doc:
+      case payload[:cache_hit]
+      when :hit
+        "[cache hit]"
+      when :miss
+        "[cache miss]"
+      end
+    end
 
     def log_rendering_start(payload)
       info do
-        message = "  Rendering #{from_rails_root(payload[:identifier])}"
+        message = "  Rendering #{from_rails_root(payload[:identifier])}".dup
         message << " within #{from_rails_root(payload[:layout])}" if payload[:layout]
         message
       end
diff --git a/actionview/lib/action_view/lookup_context.rb b/actionview/lib/action_view/lookup_context.rb
index 9db1460ee7..0e56eca35c 100644
--- a/actionview/lib/action_view/lookup_context.rb
+++ b/actionview/lib/action_view/lookup_context.rb
@@ -1,7 +1,9 @@
-require 'concurrent/map'
-require 'active_support/core_ext/module/remove_method'
-require 'active_support/core_ext/module/attribute_accessors'
-require 'action_view/template/resolver'
+# frozen_string_literal: true
+
+require "concurrent/map"
+require "active_support/core_ext/module/remove_method"
+require "active_support/core_ext/module/attribute_accessors"
+require "action_view/template/resolver"
 
 module ActionView
   # = Action View Lookup Context
@@ -14,14 +16,12 @@ module ActionView
   class LookupContext #:nodoc:
     attr_accessor :prefixes, :rendered_format
 
-    mattr_accessor :fallbacks
-    @@fallbacks = FallbackFileSystemResolver.instances
+    mattr_accessor :fallbacks, default: FallbackFileSystemResolver.instances
 
-    mattr_accessor :registered_details
-    self.registered_details = []
+    mattr_accessor :registered_details, default: []
 
     def self.register_detail(name, &block)
-      self.registered_details << name
+      registered_details << name
       Accessors::DEFAULT_PROCS[name] = block
 
       Accessors.send :define_method, :"default_#{name}", &block
@@ -93,9 +93,9 @@ module ActionView
         @cache = old_value
       end
 
-    protected
+    private
 
-      def _set_detail(key, value)
+      def _set_detail(key, value) # :doc:
         @details = @details.dup if @details_key
         @details_key = nil
         @details[key] = value
@@ -149,16 +149,16 @@ module ActionView
         added_resolvers.times { view_paths.pop }
       end
 
-    protected
+    private
 
-      def args_for_lookup(name, prefixes, partial, keys, details_options) #:nodoc:
+      def args_for_lookup(name, prefixes, partial, keys, details_options)
         name, prefixes = normalize_name(name, prefixes)
         details, details_key = detail_args_for(details_options)
         [name, prefixes, partial || false, details, details_key, keys]
       end
 
       # Compute details hash and key according to user options (e.g. passed from #render).
-      def detail_args_for(options)
+      def detail_args_for(options) # :doc:
         return @details, details_key if options.empty? # most common path.
         user_details = @details.merge(options)
 
@@ -171,13 +171,13 @@ module ActionView
         [user_details, details_key]
       end
 
-      def args_for_any(name, prefixes, partial) # :nodoc:
+      def args_for_any(name, prefixes, partial)
         name, prefixes = normalize_name(name, prefixes)
         details, details_key = detail_args_for_any
         [name, prefixes, partial || false, details, details_key]
       end
 
-      def detail_args_for_any # :nodoc:
+      def detail_args_for_any
         @detail_args_for_any ||= begin
           details = {}
 
@@ -200,15 +200,15 @@ module ActionView
       # Support legacy foo.erb names even though we now ignore .erb
       # as well as incorrectly putting part of the path in the template
       # name instead of the prefix.
-      def normalize_name(name, prefixes) #:nodoc:
+      def normalize_name(name, prefixes)
         prefixes = prefixes.presence
-        parts    = name.to_s.split('/'.freeze)
+        parts    = name.to_s.split("/".freeze)
         parts.shift if parts.first.empty?
-        name     = parts.pop
+        name = parts.pop
 
         return name, prefixes || [""] if parts.empty?
 
-        parts    = parts.join('/'.freeze)
+        parts    = parts.join("/".freeze)
         prefixes = prefixes ? prefixes.map { |p| "#{p}/#{parts}" } : [parts]
 
         return name, prefixes
diff --git a/actionview/lib/action_view/model_naming.rb b/actionview/lib/action_view/model_naming.rb
index b6ed13424e..23cca8d607 100644
--- a/actionview/lib/action_view/model_naming.rb
+++ b/actionview/lib/action_view/model_naming.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActionView
   module ModelNaming #:nodoc:
     # Converts the given object to an ActiveModel compliant one.
diff --git a/actionview/lib/action_view/path_set.rb b/actionview/lib/action_view/path_set.rb
index f68d2a77ed..691b53e2da 100644
--- a/actionview/lib/action_view/path_set.rb
+++ b/actionview/lib/action_view/path_set.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActionView #:nodoc:
   # = Action View PathSet
   #
@@ -69,30 +71,30 @@ module ActionView #:nodoc:
 
     private
 
-    def _find_all(path, prefixes, args, outside_app)
-      prefixes = [prefixes] if String === prefixes
-      prefixes.each do |prefix|
-        paths.each do |resolver|
-          if outside_app
-            templates = resolver.find_all_anywhere(path, prefix, *args)
-          else
-            templates = resolver.find_all(path, prefix, *args)
+      def _find_all(path, prefixes, args, outside_app)
+        prefixes = [prefixes] if String === prefixes
+        prefixes.each do |prefix|
+          paths.each do |resolver|
+            if outside_app
+              templates = resolver.find_all_anywhere(path, prefix, *args)
+            else
+              templates = resolver.find_all(path, prefix, *args)
+            end
+            return templates unless templates.empty?
           end
-          return templates unless templates.empty?
         end
+        []
       end
-      []
-    end
 
-    def typecast(paths)
-      paths.map do |path|
-        case path
-        when Pathname, String
-          OptimizedFileSystemResolver.new path.to_s
-        else
-          path
+      def typecast(paths)
+        paths.map do |path|
+          case path
+          when Pathname, String
+            OptimizedFileSystemResolver.new path.to_s
+          else
+            path
+          end
         end
       end
-    end
   end
 end
diff --git a/actionview/lib/action_view/railtie.rb b/actionview/lib/action_view/railtie.rb
index dfb99f4ea9..73dfb267bb 100644
--- a/actionview/lib/action_view/railtie.rb
+++ b/actionview/lib/action_view/railtie.rb
@@ -1,11 +1,13 @@
+# frozen_string_literal: true
+
 require "action_view"
 require "rails"
 
 module ActionView
   # = Action View Railtie
-  class Railtie < Rails::Railtie # :nodoc:
+  class Railtie < Rails::Engine # :nodoc:
     config.action_view = ActiveSupport::OrderedOptions.new
-    config.action_view.embed_authenticity_token_in_remote_forms = false
+    config.action_view.embed_authenticity_token_in_remote_forms = nil
     config.action_view.debug_missing_translation = true
 
     config.eager_load_namespaces << ActionView
@@ -17,13 +19,29 @@ module ActionView
       end
     end
 
+    initializer "action_view.form_with_generates_remote_forms" do |app|
+      ActiveSupport.on_load(:action_view) do
+        form_with_generates_remote_forms = app.config.action_view.delete(:form_with_generates_remote_forms)
+        ActionView::Helpers::FormHelper.form_with_generates_remote_forms = form_with_generates_remote_forms
+      end
+    end
+
+    initializer "action_view.form_with_generates_ids" do |app|
+      ActiveSupport.on_load(:action_view) do
+        form_with_generates_ids = app.config.action_view.delete(:form_with_generates_ids)
+        unless form_with_generates_ids.nil?
+          ActionView::Helpers::FormHelper.form_with_generates_ids = form_with_generates_ids
+        end
+      end
+    end
+
     initializer "action_view.logger" do
       ActiveSupport.on_load(:action_view) { self.logger ||= Rails.logger }
     end
 
     initializer "action_view.set_configs" do |app|
       ActiveSupport.on_load(:action_view) do
-        app.config.action_view.each do |k,v|
+        app.config.action_view.each do |k, v|
           send "#{k}=", v
         end
       end
@@ -39,8 +57,8 @@ module ActionView
 
     initializer "action_view.per_request_digest_cache" do |app|
       ActiveSupport.on_load(:action_view) do
-        if app.config.consider_all_requests_local
-          app.executor.to_run { ActionView::LookupContext::DetailsKey.clear }
+        unless ActionView::Resolver.caching?
+          app.executor.to_run ActionView::Digestor::PerExecutionDigestCacheExpiry
         end
       end
     end
diff --git a/actionview/lib/action_view/record_identifier.rb b/actionview/lib/action_view/record_identifier.rb
index 4a2547b0fb..1310a1ce0a 100644
--- a/actionview/lib/action_view/record_identifier.rb
+++ b/actionview/lib/action_view/record_identifier.rb
@@ -1,5 +1,7 @@
-require 'active_support/core_ext/module'
-require 'action_view/model_naming'
+# frozen_string_literal: true
+
+require "active_support/core_ext/module"
+require "action_view/model_naming"
 
 module ActionView
   # RecordIdentifier encapsulates methods used by various ActionView helpers
@@ -57,8 +59,8 @@ module ActionView
 
     include ModelNaming
 
-    JOIN = '_'.freeze
-    NEW = 'new'.freeze
+    JOIN = "_".freeze
+    NEW = "new".freeze
 
     # The DOM class convention is to use the singular form of an object or class.
     #
@@ -92,7 +94,7 @@ module ActionView
       end
     end
 
-  protected
+  private
 
     # Returns a string representation of the key attribute(s) that is suitable for use in an HTML DOM id.
     # This can be overwritten to customize the default generated string representation if desired.
@@ -102,7 +104,7 @@ module ActionView
     # overwritten version of the method. By default, this implementation passes the key string through a
     # method that replaces all characters that are invalid inside DOM ids, with valid ones. You need to
     # make sure yourself that your dom ids are valid, in case you overwrite this method.
-    def record_key_for_dom_id(record)
+    def record_key_for_dom_id(record) # :doc:
       key = convert_to_model(record).to_key
       key ? key.join(JOIN) : key
     end
diff --git a/actionview/lib/action_view/renderer/abstract_renderer.rb b/actionview/lib/action_view/renderer/abstract_renderer.rb
index 1dddf53df0..20b2523cac 100644
--- a/actionview/lib/action_view/renderer/abstract_renderer.rb
+++ b/actionview/lib/action_view/renderer/abstract_renderer.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActionView
   # This class defines the interface for a renderer. Each class that
   # subclasses +AbstractRenderer+ is used by the base +Renderer+ class to
@@ -15,7 +17,7 @@ module ActionView
   # that new object is called in turn. This abstracts the setup and rendering
   # into a separate classes for partials and templates.
   class AbstractRenderer #:nodoc:
-    delegate :find_template, :find_file, :template_exists?, :any_templates?, :with_fallbacks, :with_layout_format, :formats, :to => :@lookup_context
+    delegate :find_template, :find_file, :template_exists?, :any_templates?, :with_fallbacks, :with_layout_format, :formats, to: :@lookup_context
 
     def initialize(lookup_context)
       @lookup_context = lookup_context
@@ -25,29 +27,29 @@ module ActionView
       raise NotImplementedError
     end
 
-    protected
+    private
 
-    def extract_details(options)
-      @lookup_context.registered_details.each_with_object({}) do |key, details|
-        value = options[key]
+      def extract_details(options) # :doc:
+        @lookup_context.registered_details.each_with_object({}) do |key, details|
+          value = options[key]
 
-        details[key] = Array(value) if value
+          details[key] = Array(value) if value
+        end
       end
-    end
 
-    def instrument(name, **options)
-      options[:identifier] ||= (@template && @template.identifier) || @path
+      def instrument(name, **options) # :doc:
+        options[:identifier] ||= (@template && @template.identifier) || @path
 
-      ActiveSupport::Notifications.instrument("render_#{name}.action_view", options) do |payload|
-        yield payload
+        ActiveSupport::Notifications.instrument("render_#{name}.action_view", options) do |payload|
+          yield payload
+        end
       end
-    end
 
-    def prepend_formats(formats)
-      formats = Array(formats)
-      return if formats.empty? || @lookup_context.html_fallback_for_js
+      def prepend_formats(formats) # :doc:
+        formats = Array(formats)
+        return if formats.empty? || @lookup_context.html_fallback_for_js
 
-      @lookup_context.formats = formats | @lookup_context.formats
-    end
+        @lookup_context.formats = formats | @lookup_context.formats
+      end
   end
 end
diff --git a/actionview/lib/action_view/renderer/partial_renderer.rb b/actionview/lib/action_view/renderer/partial_renderer.rb
index 13b4ec6133..5b40af4f2f 100644
--- a/actionview/lib/action_view/renderer/partial_renderer.rb
+++ b/actionview/lib/action_view/renderer/partial_renderer.rb
@@ -1,5 +1,7 @@
-require 'action_view/renderer/partial_renderer/collection_caching'
-require 'concurrent/map'
+# frozen_string_literal: true
+
+require "concurrent/map"
+require "action_view/renderer/partial_renderer/collection_caching"
 
 module ActionView
   class PartialIteration
@@ -50,12 +52,12 @@ module ActionView
   #     <%= render partial: "ad", locals: { ad: ad } %>
   #   <% end %>
   #
-  # This would first render "advertiser/_account.html.erb" with @buyer passed in as the local variable +account+, then
-  # render "advertiser/_ad.html.erb" and pass the local variable +ad+ to the template for display.
+  # This would first render <tt>advertiser/_account.html.erb</tt> with <tt>@buyer</tt> passed in as the local variable +account+, then
+  # render <tt>advertiser/_ad.html.erb</tt> and pass the local variable +ad+ to the template for display.
   #
   # == The :as and :object options
   #
-  # By default <tt>ActionView::PartialRenderer</tt> doesn't have any local variables.
+  # By default ActionView::PartialRenderer doesn't have any local variables.
   # The <tt>:object</tt> option can be used to pass an object to the partial. For instance:
   #
   #   <%= render partial: "account", object: @buyer %>
@@ -83,7 +85,7 @@ module ActionView
   #
   #   <%= render partial: "ad", collection: @advertisements %>
   #
-  # This will render "advertiser/_ad.html.erb" and pass the local variable +ad+ to the template for display. An
+  # This will render <tt>advertiser/_ad.html.erb</tt> and pass the local variable +ad+ to the template for display. An
   # iteration object will automatically be made available to the template with a name of the form
   # +partial_name_iteration+. The iteration object has knowledge about which index the current object has in
   # the collection and the total size of the collection. The iteration object also has two convenience methods,
@@ -98,8 +100,8 @@ module ActionView
   #
   #   <%= render partial: "ad", collection: @advertisements, spacer_template: "ad_divider" %>
   #
-  # If the given <tt>:collection</tt> is nil or empty, <tt>render</tt> will return nil. This will allow you
-  # to specify a text which will displayed instead by using this form:
+  # If the given <tt>:collection</tt> is +nil+ or empty, <tt>render</tt> will return +nil+. This will allow you
+  # to specify a text which will be displayed instead by using this form:
   #
   #   <%= render(partial: "ad", collection: @advertisements) || "There's no ad to be displayed" %>
   #
@@ -112,18 +114,18 @@ module ActionView
   #
   #   <%= render partial: "advertisement/ad", locals: { ad: @advertisement } %>
   #
-  # This will render the partial "advertisement/_ad.html.erb" regardless of which controller this is being called from.
+  # This will render the partial <tt>advertisement/_ad.html.erb</tt> regardless of which controller this is being called from.
   #
-  # == \Rendering objects that respond to `to_partial_path`
+  # == \Rendering objects that respond to +to_partial_path+
   #
   # Instead of explicitly naming the location of a partial, you can also let PartialRenderer do the work
-  # and pick the proper path by checking `to_partial_path` method.
+  # and pick the proper path by checking +to_partial_path+ method.
   #
   #  # @account.to_partial_path returns 'accounts/account', so it can be used to replace:
   #  # <%= render partial: "accounts/account", locals: { account: @account} %>
   #  <%= render partial: @account %>
   #
-  #  # @posts is an array of Post instances, so every post record returns 'posts/post' on `to_partial_path`,
+  #  # @posts is an array of Post instances, so every post record returns 'posts/post' on +to_partial_path+,
   #  # that's why we can replace:
   #  # <%= render partial: "posts/post", collection: @posts %>
   #  <%= render partial: @posts %>
@@ -143,7 +145,7 @@ module ActionView
   #  # <%= render partial: "accounts/account", locals: { account: @account} %>
   #  <%= render @account %>
   #
-  #  # @posts is an array of Post instances, so every post record returns 'posts/post' on `to_partial_path`,
+  #  # @posts is an array of Post instances, so every post record returns 'posts/post' on +to_partial_path+,
   #  # that's why we can replace:
   #  # <%= render partial: "posts/post", collection: @posts %>
   #  <%= render @posts %>
@@ -307,243 +309,244 @@ module ActionView
       if @collection
         render_collection
       else
-        instrument(:partial) do
-          render_partial
-        end
+        render_partial
       end
     end
 
     private
 
-    def render_collection
-      instrument(:collection, count: @collection.size) do |payload|
-        return nil if @collection.blank?
+      def render_collection
+        instrument(:collection, count: @collection.size) do |payload|
+          return nil if @collection.blank?
 
-        if @options.key?(:spacer_template)
-          spacer = find_template(@options[:spacer_template], @locals.keys).render(@view, @locals)
-        end
+          if @options.key?(:spacer_template)
+            spacer = find_template(@options[:spacer_template], @locals.keys).render(@view, @locals)
+          end
 
-        cache_collection_render(payload) do
-          @template ? collection_with_template : collection_without_template
-        end.join(spacer).html_safe
+          cache_collection_render(payload) do
+            @template ? collection_with_template : collection_without_template
+          end.join(spacer).html_safe
+        end
       end
-    end
 
-    def render_partial
-      view, locals, block = @view, @locals, @block
-      object, as = @object, @variable
+      def render_partial
+        instrument(:partial) do |payload|
+          view, locals, block = @view, @locals, @block
+          object, as = @object, @variable
 
-      if !block && (layout = @options[:layout])
-        layout = find_template(layout.to_s, @template_keys)
-      end
+          if !block && (layout = @options[:layout])
+            layout = find_template(layout.to_s, @template_keys)
+          end
 
-      object = locals[as] if object.nil? # Respect object when object is false
-      locals[as] = object if @has_object
+          object = locals[as] if object.nil? # Respect object when object is false
+          locals[as] = object if @has_object
 
-      content = @template.render(view, locals) do |*name|
-        view._layout_for(*name, &block)
+          content = @template.render(view, locals) do |*name|
+            view._layout_for(*name, &block)
+          end
+
+          content = layout.render(view, locals) { content } if layout
+          payload[:cache_hit] = view.view_renderer.cache_hits[@template.virtual_path]
+          content
+        end
       end
 
-      content = layout.render(view, locals){ content } if layout
-      content
-    end
+      # Sets up instance variables needed for rendering a partial. This method
+      # finds the options and details and extracts them. The method also contains
+      # logic that handles the type of object passed in as the partial.
+      #
+      # If +options[:partial]+ is a string, then the <tt>@path</tt> instance variable is
+      # set to that string. Otherwise, the +options[:partial]+ object must
+      # respond to +to_partial_path+ in order to setup the path.
+      def setup(context, options, block)
+        @view = context
+        @options = options
+        @block   = block
+
+        @locals  = options[:locals] || {}
+        @details = extract_details(options)
+
+        prepend_formats(options[:formats])
+
+        partial = options[:partial]
+
+        if String === partial
+          @has_object = options.key?(:object)
+          @object     = options[:object]
+          @collection = collection_from_options
+          @path       = partial
+        else
+          @has_object = true
+          @object = partial
+          @collection = collection_from_object || collection_from_options
+
+          if @collection
+            paths = @collection_data = @collection.map { |o| partial_path(o) }
+            @path = paths.uniq.one? ? paths.first : nil
+          else
+            @path = partial_path
+          end
+        end
 
-    # Sets up instance variables needed for rendering a partial. This method
-    # finds the options and details and extracts them. The method also contains
-    # logic that handles the type of object passed in as the partial.
-    #
-    # If +options[:partial]+ is a string, then the +@path+ instance variable is
-    # set to that string. Otherwise, the +options[:partial]+ object must
-    # respond to +to_partial_path+ in order to setup the path.
-    def setup(context, options, block)
-      @view   = context
-      @options = options
-      @block   = block
-
-      @locals  = options[:locals] || {}
-      @details = extract_details(options)
-
-      prepend_formats(options[:formats])
-
-      partial = options[:partial]
-
-      if String === partial
-        @has_object = options.key?(:object)
-        @object     = options[:object]
-        @collection = collection_from_options
-        @path       = partial
-      else
-        @has_object = true
-        @object = partial
-        @collection = collection_from_object || collection_from_options
+        if as = options[:as]
+          raise_invalid_option_as(as) unless /\A[a-z_]\w*\z/.match?(as.to_s)
+          as = as.to_sym
+        end
 
-        if @collection
-          paths = @collection_data = @collection.map { |o| partial_path(o) }
-          @path = paths.uniq.one? ? paths.first : nil
+        if @path
+          @variable, @variable_counter, @variable_iteration = retrieve_variable(@path, as)
+          @template_keys = retrieve_template_keys
         else
-          @path = partial_path
+          paths.map! { |path| retrieve_variable(path, as).unshift(path) }
         end
+
+        self
       end
 
-      if as = options[:as]
-        raise_invalid_option_as(as) unless as.to_s =~ /\A[a-z_]\w*\z/
-        as = as.to_sym
+      def collection_from_options
+        if @options.key?(:collection)
+          collection = @options[:collection]
+          collection ? collection.to_a : []
+        end
       end
 
-      if @path
-        @variable, @variable_counter, @variable_iteration = retrieve_variable(@path, as)
-        @template_keys = retrieve_template_keys
-      else
-        paths.map! { |path| retrieve_variable(path, as).unshift(path) }
+      def collection_from_object
+        @object.to_ary if @object.respond_to?(:to_ary)
       end
 
-      self
-    end
+      def find_partial
+        find_template(@path, @template_keys) if @path
+      end
 
-    def collection_from_options
-      if @options.key?(:collection)
-        collection = @options[:collection]
-        collection.respond_to?(:to_ary) ? collection.to_ary : []
+      def find_template(path, locals)
+        prefixes = path.include?(?/) ? [] : @lookup_context.prefixes
+        @lookup_context.find_template(path, prefixes, true, locals, @details)
       end
-    end
 
-    def collection_from_object
-      @object.to_ary if @object.respond_to?(:to_ary)
-    end
+      def collection_with_template
+        view, locals, template = @view, @locals, @template
+        as, counter, iteration = @variable, @variable_counter, @variable_iteration
 
-    def find_partial
-      find_template(@path, @template_keys) if @path
-    end
+        if layout = @options[:layout]
+          layout = find_template(layout, @template_keys)
+        end
 
-    def find_template(path, locals)
-      prefixes = path.include?(?/) ? [] : @lookup_context.prefixes
-      @lookup_context.find_template(path, prefixes, true, locals, @details)
-    end
+        partial_iteration = PartialIteration.new(@collection.size)
+        locals[iteration] = partial_iteration
 
-    def collection_with_template
-      view, locals, template = @view, @locals, @template
-      as, counter, iteration = @variable, @variable_counter, @variable_iteration
+        @collection.map do |object|
+          locals[as]        = object
+          locals[counter]   = partial_iteration.index
 
-      if layout = @options[:layout]
-        layout = find_template(layout, @template_keys)
+          content = template.render(view, locals)
+          content = layout.render(view, locals) { content } if layout
+          partial_iteration.iterate!
+          content
+        end
       end
 
-      partial_iteration = PartialIteration.new(@collection.size)
-      locals[iteration] = partial_iteration
+      def collection_without_template
+        view, locals, collection_data = @view, @locals, @collection_data
+        cache = {}
+        keys  = @locals.keys
 
-      @collection.map do |object|
-        locals[as]        = object
-        locals[counter]   = partial_iteration.index
+        partial_iteration = PartialIteration.new(@collection.size)
 
-        content = template.render(view, locals)
-        content = layout.render(view, locals) { content } if layout
-        partial_iteration.iterate!
-        content
-      end
-    end
+        @collection.map do |object|
+          index = partial_iteration.index
+          path, as, counter, iteration = collection_data[index]
 
-    def collection_without_template
-      view, locals, collection_data = @view, @locals, @collection_data
-      cache = {}
-      keys  = @locals.keys
+          locals[as]        = object
+          locals[counter]   = index
+          locals[iteration] = partial_iteration
 
-      partial_iteration = PartialIteration.new(@collection.size)
-
-      @collection.map do |object|
-        index = partial_iteration.index
-        path, as, counter, iteration = collection_data[index]
-
-        locals[as]        = object
-        locals[counter]   = index
-        locals[iteration] = partial_iteration
-
-        template = (cache[path] ||= find_template(path, keys + [as, counter]))
-        content = template.render(view, locals)
-        partial_iteration.iterate!
-        content
+          template = (cache[path] ||= find_template(path, keys + [as, counter, iteration]))
+          content = template.render(view, locals)
+          partial_iteration.iterate!
+          content
+        end
       end
-    end
 
-    # Obtains the path to where the object's partial is located. If the object
-    # responds to +to_partial_path+, then +to_partial_path+ will be called and
-    # will provide the path. If the object does not respond to +to_partial_path+,
-    # then an +ArgumentError+ is raised.
-    #
-    # If +prefix_partial_path_with_controller_namespace+ is true, then this
-    # method will prefix the partial paths with a namespace.
-    def partial_path(object = @object)
-      object = object.to_model if object.respond_to?(:to_model)
-
-      path = if object.respond_to?(:to_partial_path)
-        object.to_partial_path
-      else
-        raise ArgumentError.new("'#{object.inspect}' is not an ActiveModel-compatible object. It must implement :to_partial_path.")
+      # Obtains the path to where the object's partial is located. If the object
+      # responds to +to_partial_path+, then +to_partial_path+ will be called and
+      # will provide the path. If the object does not respond to +to_partial_path+,
+      # then an +ArgumentError+ is raised.
+      #
+      # If +prefix_partial_path_with_controller_namespace+ is true, then this
+      # method will prefix the partial paths with a namespace.
+      def partial_path(object = @object)
+        object = object.to_model if object.respond_to?(:to_model)
+
+        path = if object.respond_to?(:to_partial_path)
+          object.to_partial_path
+        else
+          raise ArgumentError.new("'#{object.inspect}' is not an ActiveModel-compatible object. It must implement :to_partial_path.")
+        end
+
+        if @view.prefix_partial_path_with_controller_namespace
+          prefixed_partial_names[path] ||= merge_prefix_into_object_path(@context_prefix, path.dup)
+        else
+          path
+        end
       end
 
-      if @view.prefix_partial_path_with_controller_namespace
-        prefixed_partial_names[path] ||= merge_prefix_into_object_path(@context_prefix, path.dup)
-      else
-        path
+      def prefixed_partial_names
+        @prefixed_partial_names ||= PREFIXED_PARTIAL_NAMES[@context_prefix]
       end
-    end
 
-    def prefixed_partial_names
-      @prefixed_partial_names ||= PREFIXED_PARTIAL_NAMES[@context_prefix]
-    end
+      def merge_prefix_into_object_path(prefix, object_path)
+        if prefix.include?(?/) && object_path.include?(?/)
+          prefixes = []
+          prefix_array = File.dirname(prefix).split("/")
+          object_path_array = object_path.split("/")[0..-3] # skip model dir & partial
 
-    def merge_prefix_into_object_path(prefix, object_path)
-      if prefix.include?(?/) && object_path.include?(?/)
-        prefixes = []
-        prefix_array = File.dirname(prefix).split('/')
-        object_path_array = object_path.split('/')[0..-3] # skip model dir & partial
+          prefix_array.each_with_index do |dir, index|
+            break if dir == object_path_array[index]
+            prefixes << dir
+          end
 
-        prefix_array.each_with_index do |dir, index|
-          break if dir == object_path_array[index]
-          prefixes << dir
+          (prefixes << object_path).join("/")
+        else
+          object_path
         end
-
-        (prefixes << object_path).join("/")
-      else
-        object_path
       end
-    end
 
-    def retrieve_template_keys
-      keys = @locals.keys
-      keys << @variable if @has_object || @collection
-      if @collection
-        keys << @variable_counter
-        keys << @variable_iteration
+      def retrieve_template_keys
+        keys = @locals.keys
+        keys << @variable if @has_object || @collection
+        if @collection
+          keys << @variable_counter
+          keys << @variable_iteration
+        end
+        keys
       end
-      keys
-    end
 
-    def retrieve_variable(path, as)
-      variable = as || begin
-        base = path[-1] == "/".freeze ? "".freeze : File.basename(path)
-        raise_invalid_identifier(path) unless base =~ /\A_?(.*?)(?:\.\w+)*\z/
-        $1.to_sym
-      end
-      if @collection
-        variable_counter = :"#{variable}_counter"
-        variable_iteration = :"#{variable}_iteration"
+      def retrieve_variable(path, as)
+        variable = as || begin
+          base = path[-1] == "/".freeze ? "".freeze : File.basename(path)
+          raise_invalid_identifier(path) unless base =~ /\A_?(.*?)(?:\.\w+)*\z/
+          $1.to_sym
+        end
+        if @collection
+          variable_counter = :"#{variable}_counter"
+          variable_iteration = :"#{variable}_iteration"
+        end
+        [variable, variable_counter, variable_iteration]
       end
-      [variable, variable_counter, variable_iteration]
-    end
 
-    IDENTIFIER_ERROR_MESSAGE = "The partial name (%s) is not a valid Ruby identifier; " +
-                               "make sure your partial name starts with underscore."
+      IDENTIFIER_ERROR_MESSAGE = "The partial name (%s) is not a valid Ruby identifier; " \
+                                 "make sure your partial name starts with underscore."
 
-    OPTION_AS_ERROR_MESSAGE  = "The value (%s) of the option `as` is not a valid Ruby identifier; " +
-                               "make sure it starts with lowercase letter, " +
-                               "and is followed by any combination of letters, numbers and underscores."
+      OPTION_AS_ERROR_MESSAGE  = "The value (%s) of the option `as` is not a valid Ruby identifier; " \
+                                 "make sure it starts with lowercase letter, " \
+                                 "and is followed by any combination of letters, numbers and underscores."
 
-    def raise_invalid_identifier(path)
-      raise ArgumentError.new(IDENTIFIER_ERROR_MESSAGE % (path))
-    end
+      def raise_invalid_identifier(path)
+        raise ArgumentError.new(IDENTIFIER_ERROR_MESSAGE % (path))
+      end
 
-    def raise_invalid_option_as(as)
-      raise ArgumentError.new(OPTION_AS_ERROR_MESSAGE % (as))
-    end
+      def raise_invalid_option_as(as)
+        raise ArgumentError.new(OPTION_AS_ERROR_MESSAGE % (as))
+      end
   end
 end
diff --git a/actionview/lib/action_view/renderer/partial_renderer/collection_caching.rb b/actionview/lib/action_view/renderer/partial_renderer/collection_caching.rb
index f7deba94ce..db52919e91 100644
--- a/actionview/lib/action_view/renderer/partial_renderer/collection_caching.rb
+++ b/actionview/lib/action_view/renderer/partial_renderer/collection_caching.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActionView
   module CollectionCaching # :nodoc:
     extend ActiveSupport::Concern
@@ -5,7 +7,7 @@ module ActionView
     included do
       # Fallback cache store if Action View is used without Rails.
       # Otherwise overridden in Railtie to use Rails.cache.
-      mattr_accessor(:collection_cache) { ActiveSupport::Cache::MemoryStore.new }
+      mattr_accessor :collection_cache, default: ActiveSupport::Cache::MemoryStore.new
     end
 
     private
@@ -25,14 +27,20 @@ module ActionView
         end
       end
 
+      def callable_cache_key?
+        @options[:cached].respond_to?(:call)
+      end
+
       def collection_by_cache_keys
+        seed = callable_cache_key? ? @options[:cached] : ->(i) { i }
+
         @collection.each_with_object({}) do |item, hash|
-          hash[expanded_cache_key(item)] = item
+          hash[expanded_cache_key(seed.call(item))] = item
         end
       end
 
       def expanded_cache_key(key)
-        key = @view.fragment_cache_key(@view.cache_fragment_name(key, virtual_path: @template.virtual_path))
+        key = @view.combined_fragment_cache_key(@view.cache_fragment_name(key, virtual_path: @template.virtual_path))
         key.frozen? ? key.dup : key # #read_multi & #write may require mutability, Dalli 2.6.0.
       end
 
diff --git a/actionview/lib/action_view/renderer/renderer.rb b/actionview/lib/action_view/renderer/renderer.rb
index 2a3b89aebf..3f3a97529d 100644
--- a/actionview/lib/action_view/renderer/renderer.rb
+++ b/actionview/lib/action_view/renderer/renderer.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActionView
   # This is the main entry point for rendering. It basically delegates
   # to other objects like TemplateRenderer and PartialRenderer which
@@ -46,5 +48,9 @@ module ActionView
     def render_partial(context, options, &block) #:nodoc:
       PartialRenderer.new(@lookup_context).render(context, options, block)
     end
+
+    def cache_hits # :nodoc:
+      @cache_hits ||= {}
+    end
   end
 end
diff --git a/actionview/lib/action_view/renderer/streaming_template_renderer.rb b/actionview/lib/action_view/renderer/streaming_template_renderer.rb
index f38e2764d0..276a28ce07 100644
--- a/actionview/lib/action_view/renderer/streaming_template_renderer.rb
+++ b/actionview/lib/action_view/renderer/streaming_template_renderer.rb
@@ -1,10 +1,11 @@
-require 'fiber'
+# frozen_string_literal: true
+
+require "fiber"
 
 module ActionView
   # == TODO
   #
   # * Support streaming from child templates, partials and so on.
-  # * Integrate exceptions with exceptron
   # * Rack::Cache needs to support streaming bodies
   class StreamingTemplateRenderer < TemplateRenderer #:nodoc:
     # A valid Rack::Body (i.e. it responds to each).
@@ -27,17 +28,16 @@ module ActionView
 
       private
 
-      # This is the same logging logic as in ShowExceptions middleware.
-      # TODO Once "exceptron" is in, refactor this piece to simply re-use exceptron.
-      def log_error(exception) #:nodoc:
-        logger = ActionView::Base.logger
-        return unless logger
+        # This is the same logging logic as in ShowExceptions middleware.
+        def log_error(exception)
+          logger = ActionView::Base.logger
+          return unless logger
 
-        message = "\n#{exception.class} (#{exception.message}):\n"
-        message << exception.annoted_source_code.to_s if exception.respond_to?(:annoted_source_code)
-        message << "  " << exception.backtrace.join("\n  ")
-        logger.fatal("#{message}\n\n")
-      end
+          message = "\n#{exception.class} (#{exception.message}):\n".dup
+          message << exception.annoted_source_code.to_s if exception.respond_to?(:annoted_source_code)
+          message << "  " << exception.backtrace.join("\n  ")
+          logger.fatal("#{message}\n\n")
+        end
     end
 
     # For streaming, instead of rendering a given a template, we return a Body
@@ -56,48 +56,50 @@ module ActionView
 
     private
 
-    def delayed_render(buffer, template, layout, view, locals)
-      # Wrap the given buffer in the StreamingBuffer and pass it to the
-      # underlying template handler. Now, every time something is concatenated
-      # to the buffer, it is not appended to an array, but streamed straight
-      # to the client.
-      output  = ActionView::StreamingBuffer.new(buffer)
-      yielder = lambda { |*name| view._layout_for(*name) }
-
-      instrument(:template, :identifier => template.identifier, :layout => layout.try(:virtual_path)) do
-        fiber = Fiber.new do
-          if layout
-            layout.render(view, locals, output, &yielder)
-          else
-            # If you don't have a layout, just render the thing
-            # and concatenate the final result. This is the same
-            # as a layout with just <%= yield %>
-            output.safe_concat view._layout_for
+      def delayed_render(buffer, template, layout, view, locals)
+        # Wrap the given buffer in the StreamingBuffer and pass it to the
+        # underlying template handler. Now, every time something is concatenated
+        # to the buffer, it is not appended to an array, but streamed straight
+        # to the client.
+        output  = ActionView::StreamingBuffer.new(buffer)
+        yielder = lambda { |*name| view._layout_for(*name) }
+
+        instrument(:template, identifier: template.identifier, layout: layout.try(:virtual_path)) do
+          outer_config = I18n.config
+          fiber = Fiber.new do
+            I18n.config = outer_config
+            if layout
+              layout.render(view, locals, output, &yielder)
+            else
+              # If you don't have a layout, just render the thing
+              # and concatenate the final result. This is the same
+              # as a layout with just <%= yield %>
+              output.safe_concat view._layout_for
+            end
           end
-        end
 
-        # Set the view flow to support streaming. It will be aware
-        # when to stop rendering the layout because it needs to search
-        # something in the template and vice-versa.
-        view.view_flow = StreamingFlow.new(view, fiber)
+          # Set the view flow to support streaming. It will be aware
+          # when to stop rendering the layout because it needs to search
+          # something in the template and vice-versa.
+          view.view_flow = StreamingFlow.new(view, fiber)
 
-        # Yo! Start the fiber!
-        fiber.resume
+          # Yo! Start the fiber!
+          fiber.resume
 
-        # If the fiber is still alive, it means we need something
-        # from the template, so start rendering it. If not, it means
-        # the layout exited without requiring anything from the template.
-        if fiber.alive?
-          content = template.render(view, locals, &yielder)
+          # If the fiber is still alive, it means we need something
+          # from the template, so start rendering it. If not, it means
+          # the layout exited without requiring anything from the template.
+          if fiber.alive?
+            content = template.render(view, locals, &yielder)
 
-          # Once rendering the template is done, sets its content in the :layout key.
-          view.view_flow.set(:layout, content)
+            # Once rendering the template is done, sets its content in the :layout key.
+            view.view_flow.set(:layout, content)
 
-          # In case the layout continues yielding, we need to resume
-          # the fiber until all yields are handled.
-          fiber.resume while fiber.alive?
+            # In case the layout continues yielding, we need to resume
+            # the fiber until all yields are handled.
+            fiber.resume while fiber.alive?
+          end
         end
       end
-    end
   end
 end
diff --git a/actionview/lib/action_view/renderer/template_renderer.rb b/actionview/lib/action_view/renderer/template_renderer.rb
index 1d6afb90fe..ce8908924a 100644
--- a/actionview/lib/action_view/renderer/template_renderer.rb
+++ b/actionview/lib/action_view/renderer/template_renderer.rb
@@ -1,4 +1,6 @@
-require 'active_support/core_ext/object/try'
+# frozen_string_literal: true
+
+require "active_support/core_ext/object/try"
 
 module ActionView
   class TemplateRenderer < AbstractRenderer #:nodoc:
@@ -16,87 +18,85 @@ module ActionView
 
     private
 
-    # Determine the template to be rendered using the given options.
-    def determine_template(options)
-      keys = options.has_key?(:locals) ? options[:locals].keys : []
+      # Determine the template to be rendered using the given options.
+      def determine_template(options)
+        keys = options.has_key?(:locals) ? options[:locals].keys : []
 
-      if options.key?(:body)
-        Template::Text.new(options[:body])
-      elsif options.key?(:text)
-        Template::Text.new(options[:text], formats.first)
-      elsif options.key?(:plain)
-        Template::Text.new(options[:plain])
-      elsif options.key?(:html)
-        Template::HTML.new(options[:html], formats.first)
-      elsif options.key?(:file)
-        with_fallbacks { find_file(options[:file], nil, false, keys, @details) }
-      elsif options.key?(:inline)
-        handler = Template.handler_for_extension(options[:type] || "erb")
-        Template.new(options[:inline], "inline template", handler, :locals => keys)
-      elsif options.key?(:template)
-        if options[:template].respond_to?(:render)
-          options[:template]
+        if options.key?(:body)
+          Template::Text.new(options[:body])
+        elsif options.key?(:plain)
+          Template::Text.new(options[:plain])
+        elsif options.key?(:html)
+          Template::HTML.new(options[:html], formats.first)
+        elsif options.key?(:file)
+          with_fallbacks { find_file(options[:file], nil, false, keys, @details) }
+        elsif options.key?(:inline)
+          handler = Template.handler_for_extension(options[:type] || "erb")
+          Template.new(options[:inline], "inline template", handler, locals: keys)
+        elsif options.key?(:template)
+          if options[:template].respond_to?(:render)
+            options[:template]
+          else
+            find_template(options[:template], options[:prefixes], false, keys, @details)
+          end
         else
-          find_template(options[:template], options[:prefixes], false, keys, @details)
+          raise ArgumentError, "You invoked render but did not give any of :partial, :template, :inline, :file, :plain, :html or :body option."
         end
-      else
-        raise ArgumentError, "You invoked render but did not give any of :partial, :template, :inline, :file, :plain, :html, :text or :body option."
       end
-    end
 
-    # Renders the given template. A string representing the layout can be
-    # supplied as well.
-    def render_template(template, layout_name = nil, locals = nil) #:nodoc:
-      view, locals = @view, locals || {}
+      # Renders the given template. A string representing the layout can be
+      # supplied as well.
+      def render_template(template, layout_name = nil, locals = nil)
+        view, locals = @view, locals || {}
 
-      render_with_layout(layout_name, locals) do |layout|
-        instrument(:template, :identifier => template.identifier, :layout => layout.try(:virtual_path)) do
-          template.render(view, locals) { |*name| view._layout_for(*name) }
+        render_with_layout(layout_name, locals) do |layout|
+          instrument(:template, identifier: template.identifier, layout: layout.try(:virtual_path)) do
+            template.render(view, locals) { |*name| view._layout_for(*name) }
+          end
         end
       end
-    end
 
-    def render_with_layout(path, locals) #:nodoc:
-      layout  = path && find_layout(path, locals.keys, [formats.first])
-      content = yield(layout)
+      def render_with_layout(path, locals)
+        layout  = path && find_layout(path, locals.keys, [formats.first])
+        content = yield(layout)
 
-      if layout
-        view = @view
-        view.view_flow.set(:layout, content)
-        layout.render(view, locals){ |*name| view._layout_for(*name) }
-      else
-        content
+        if layout
+          view = @view
+          view.view_flow.set(:layout, content)
+          layout.render(view, locals) { |*name| view._layout_for(*name) }
+        else
+          content
+        end
       end
-    end
 
-    # This is the method which actually finds the layout using details in the lookup
-    # context object. If no layout is found, it checks if at least a layout with
-    # the given name exists across all details before raising the error.
-    def find_layout(layout, keys, formats)
-      resolve_layout(layout, keys, formats)
-    end
+      # This is the method which actually finds the layout using details in the lookup
+      # context object. If no layout is found, it checks if at least a layout with
+      # the given name exists across all details before raising the error.
+      def find_layout(layout, keys, formats)
+        resolve_layout(layout, keys, formats)
+      end
 
-    def resolve_layout(layout, keys, formats)
-      details = @details.dup
-      details[:formats] = formats
+      def resolve_layout(layout, keys, formats)
+        details = @details.dup
+        details[:formats] = formats
 
-      case layout
-      when String
-        begin
-          if layout =~ /^\//
-            with_fallbacks { find_template(layout, nil, false, [], details) }
-          else
-            find_template(layout, nil, false, [], details)
+        case layout
+        when String
+          begin
+            if layout.start_with?("/")
+              with_fallbacks { find_template(layout, nil, false, [], details) }
+            else
+              find_template(layout, nil, false, [], details)
+            end
+          rescue ActionView::MissingTemplate
+            all_details = @details.merge(formats: @lookup_context.default_formats)
+            raise unless template_exists?(layout, nil, false, [], all_details)
           end
-        rescue ActionView::MissingTemplate
-          all_details = @details.merge(:formats => @lookup_context.default_formats)
-          raise unless template_exists?(layout, nil, false, [], all_details)
+        when Proc
+          resolve_layout(layout.call(formats), keys, formats)
+        else
+          layout
         end
-      when Proc
-        resolve_layout(layout.call(formats), keys, formats)
-      else
-        layout
       end
-    end
   end
 end
diff --git a/actionview/lib/action_view/rendering.rb b/actionview/lib/action_view/rendering.rb
index 3ca7f9d220..4e5fdfbb2d 100644
--- a/actionview/lib/action_view/rendering.rb
+++ b/actionview/lib/action_view/rendering.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require "action_view/view_paths"
 
 module ActionView
@@ -73,8 +75,7 @@ module ActionView
     end
 
     # Returns an object that is able to render templates.
-    # :api: private
-    def view_renderer
+    def view_renderer # :nodoc:
       @_view_renderer ||= ActionView::Renderer.new(lookup_context)
     end
 
@@ -90,8 +91,7 @@ module ActionView
     private
 
       # Find and render a template based on the options given.
-      # :api: private
-      def _render_template(options) #:nodoc:
+      def _render_template(options)
         variant = options.delete(:variant)
         assigns = options.delete(:assigns)
         context = view_context
@@ -104,7 +104,7 @@ module ActionView
       end
 
       # Assign the rendered format to look up context.
-      def _process_format(format) #:nodoc:
+      def _process_format(format)
         super
         lookup_context.formats = [format.to_sym]
         lookup_context.rendered_format = lookup_context.formats.first
@@ -112,8 +112,7 @@ module ActionView
 
       # Normalize args by converting render "foo" to render :action => "foo" and
       # render "foo/bar" to render :template => "foo/bar".
-      # :api: private
-      def _normalize_args(action=nil, options={})
+      def _normalize_args(action = nil, options = {})
         options = super(action, options)
         case action
         when NilClass
@@ -124,14 +123,17 @@ module ActionView
           key = action.include?(?/) ? :template : :action
           options[key] = action
         else
-          options[:partial] = action
+          if action.respond_to?(:permitted?) && action.permitted?
+            options = action
+          else
+            options[:partial] = action
+          end
         end
 
         options
       end
 
       # Normalize options.
-      # :api: private
       def _normalize_options(options)
         options = super(options)
         if options[:partial] == true
diff --git a/actionview/lib/action_view/routing_url_for.rb b/actionview/lib/action_view/routing_url_for.rb
index 45e78d1ad9..fd563f34a9 100644
--- a/actionview/lib/action_view/routing_url_for.rb
+++ b/actionview/lib/action_view/routing_url_for.rb
@@ -1,8 +1,9 @@
-require 'action_dispatch/routing/polymorphic_routes'
+# frozen_string_literal: true
+
+require "action_dispatch/routing/polymorphic_routes"
 
 module ActionView
   module RoutingUrlFor
-
     # Returns the URL for the set of +options+ provided. This takes the
     # same options as +url_for+ in Action Controller (see the
     # documentation for <tt>ActionController::Base#url_for</tt>). Note that by default
@@ -123,18 +124,15 @@ module ActionView
       controller.url_options
     end
 
-    def _routes_context #:nodoc:
-      controller
-    end
-    protected :_routes_context
-
-    def optimize_routes_generation? #:nodoc:
-      controller.respond_to?(:optimize_routes_generation?, true) ?
-        controller.optimize_routes_generation? : super
-    end
-    protected :optimize_routes_generation?
-
     private
+      def _routes_context
+        controller
+      end
+
+      def optimize_routes_generation?
+        controller.respond_to?(:optimize_routes_generation?, true) ?
+          controller.optimize_routes_generation? : super
+      end
 
       def _generate_paths_by_default
         true
diff --git a/actionview/lib/action_view/tasks/cache_digests.rake b/actionview/lib/action_view/tasks/cache_digests.rake
index 045bdf5691..dd8e94bd88 100644
--- a/actionview/lib/action_view/tasks/cache_digests.rake
+++ b/actionview/lib/action_view/tasks/cache_digests.rake
@@ -1,19 +1,21 @@
+# frozen_string_literal: true
+
 namespace :cache_digests do
-  desc 'Lookup nested dependencies for TEMPLATE (like messages/show or comments/_comment.html)'
-  task :nested_dependencies => :environment do
-    abort 'You must provide TEMPLATE for the task to run' unless ENV['TEMPLATE'].present?
+  desc "Lookup nested dependencies for TEMPLATE (like messages/show or comments/_comment.html)"
+  task nested_dependencies: :environment do
+    abort "You must provide TEMPLATE for the task to run" unless ENV["TEMPLATE"].present?
     puts JSON.pretty_generate ActionView::Digestor.tree(CacheDigests.template_name, CacheDigests.finder).children.map(&:to_dep_map)
   end
 
-  desc 'Lookup first-level dependencies for TEMPLATE (like messages/show or comments/_comment.html)'
-  task :dependencies => :environment do
-    abort 'You must provide TEMPLATE for the task to run' unless ENV['TEMPLATE'].present?
+  desc "Lookup first-level dependencies for TEMPLATE (like messages/show or comments/_comment.html)"
+  task dependencies: :environment do
+    abort "You must provide TEMPLATE for the task to run" unless ENV["TEMPLATE"].present?
     puts JSON.pretty_generate ActionView::Digestor.tree(CacheDigests.template_name, CacheDigests.finder).children.map(&:name)
   end
 
   class CacheDigests
     def self.template_name
-      ENV['TEMPLATE'].split('.', 2).first
+      ENV["TEMPLATE"].split(".", 2).first
     end
 
     def self.finder
diff --git a/actionview/lib/action_view/template.rb b/actionview/lib/action_view/template.rb
index 169ee55fdc..0c4bb73acb 100644
--- a/actionview/lib/action_view/template.rb
+++ b/actionview/lib/action_view/template.rb
@@ -1,6 +1,8 @@
-require 'active_support/core_ext/object/try'
-require 'active_support/core_ext/kernel/singleton_class'
-require 'thread'
+# frozen_string_literal: true
+
+require "active_support/core_ext/object/try"
+require "active_support/core_ext/kernel/singleton_class"
+require "thread"
 
 module ActionView
   # = Action View Template
@@ -65,8 +67,7 @@ module ActionView
     # If you want to provide an alternate mechanism for
     # specifying encodings (like ERB does via <%# encoding: ... %>),
     # you may indicate that you will handle encodings yourself
-    # by implementing <tt>self.handles_encoding?</tt>
-    # on your handler.
+    # by implementing <tt>handles_encoding?</tt> on your handler.
     #
     # If you do, Rails will not try to encode the String
     # into the default_internal, passing you the unaltered
@@ -141,7 +142,7 @@ module ActionView
     end
 
     # Returns whether the underlying handler supports streaming. If so,
-    # a streaming buffer *may* be passed when it start rendering.
+    # a streaming buffer *may* be passed when it starts rendering.
     def supports_streaming?
       handler.respond_to?(:supports_streaming?) && handler.supports_streaming?
     end
@@ -152,8 +153,8 @@ module ActionView
     # This method is instrumented as "!render_template.action_view". Notice that
     # we use a bang in this instrumentation because you don't want to
     # consume this in production. This is only slow if it's being listened to.
-    def render(view, locals, buffer=nil, &block)
-      instrument("!render_template".freeze) do
+    def render(view, locals, buffer = nil, &block)
+      instrument_render_template do
         compile!(view)
         view.send(method_name, locals, buffer, &block)
       end
@@ -180,12 +181,12 @@ module ActionView
       name    = pieces.pop
       partial = !!name.sub!(/^_/, "")
       lookup.disable_cache do
-        lookup.find_template(name, [ pieces.join('/') ], partial, @locals)
+        lookup.find_template(name, [ pieces.join("/") ], partial, @locals)
       end
     end
 
     def inspect
-      @inspect ||= defined?(Rails.root) ? identifier.sub("#{Rails.root}/", ''.freeze) : identifier
+      @inspect ||= defined?(Rails.root) ? identifier.sub("#{Rails.root}/", "".freeze) : identifier
     end
 
     # This method is responsible for properly setting the encoding of the
@@ -204,7 +205,7 @@ module ActionView
       # Look for # encoding: *. If we find one, we'll encode the
       # String in that encoding, otherwise, we'll use the
       # default external encoding.
-      if source.sub!(/\A#{ENCODING_FLAG}/, '')
+      if source.sub!(/\A#{ENCODING_FLAG}/, "")
         encoding = magic_encoding = $1
       else
         encoding = Encoding.default_external
@@ -232,11 +233,11 @@ module ActionView
       end
     end
 
-    protected
+    private
 
       # Compile a template. This method ensures a template is compiled
       # just once and removes the source after it is compiled.
-      def compile!(view) #:nodoc:
+      def compile!(view)
         return if @compiled
 
         # Templates can be used concurrently in threaded environments
@@ -277,14 +278,13 @@ module ActionView
       # encode the source into <tt>Encoding.default_internal</tt>.
       # In general, this means that templates will be UTF-8 inside of Rails,
       # regardless of the original source encoding.
-      def compile(mod) #:nodoc:
+      def compile(mod)
         encode!
-        method_name = self.method_name
         code = @handler.call(self)
 
         # Make sure that the resulting String to be eval'd is in the
         # encoding of the code
-        source = <<-end_src
+        source = <<-end_src.dup
           def #{method_name}(local_assigns, output_buffer)
             _old_virtual_path, @virtual_path = @virtual_path, #{@virtual_path.inspect};_old_output_buffer = @output_buffer;#{locals_code};#{code}
           ensure
@@ -310,7 +310,7 @@ module ActionView
         ObjectSpace.define_finalizer(self, Finalizer[method_name, mod])
       end
 
-      def handle_render_error(view, e) #:nodoc:
+      def handle_render_error(view, e)
         if e.is_a?(Template::Error)
           e.sub_template_of(self)
           raise e
@@ -324,31 +324,38 @@ module ActionView
         end
       end
 
-      def locals_code #:nodoc:
-        # Double assign to suppress the dreaded 'assigned but unused variable' warning
-        @locals.each_with_object('') { |key, code| code << "#{key} = #{key} = local_assigns[:#{key}];" }
+      def locals_code
+        # Only locals with valid variable names get set directly. Others will
+        # still be available in local_assigns.
+        locals = @locals - Module::RUBY_RESERVED_KEYWORDS
+        locals = locals.grep(/\A@?(?![A-Z0-9])(?:[[:alnum:]_]|[^\0-\177])+\z/)
+
+        # Assign for the same variable is to suppress unused variable warning
+        locals.each_with_object("".dup) { |key, code| code << "#{key} = local_assigns[:#{key}]; #{key} = #{key};" }
       end
 
-      def method_name #:nodoc:
+      def method_name
         @method_name ||= begin
-          m = "_#{identifier_method_name}__#{@identifier.hash}_#{__id__}"
-          m.tr!('-'.freeze, '_'.freeze)
+          m = "_#{identifier_method_name}__#{@identifier.hash}_#{__id__}".dup
+          m.tr!("-".freeze, "_".freeze)
           m
         end
       end
 
-      def identifier_method_name #:nodoc:
-        inspect.tr('^a-z_'.freeze, '_'.freeze)
+      def identifier_method_name
+        inspect.tr("^a-z_".freeze, "_".freeze)
       end
 
-      def instrument(action, &block)
-        payload = { virtual_path: @virtual_path, identifier: @identifier }
-        case action
-        when "!render_template".freeze
-          ActiveSupport::Notifications.instrument("!render_template.action_view".freeze, payload, &block)
-        else
-          ActiveSupport::Notifications.instrument("#{action}.action_view".freeze, payload, &block)
-        end
+      def instrument(action, &block) # :doc:
+        ActiveSupport::Notifications.instrument("#{action}.action_view", instrument_payload, &block)
+      end
+
+      def instrument_render_template(&block)
+        ActiveSupport::Notifications.instrument("!render_template.action_view".freeze, instrument_payload, &block)
+      end
+
+      def instrument_payload
+        { virtual_path: @virtual_path, identifier: @identifier }
       end
   end
 end
diff --git a/actionview/lib/action_view/template/error.rb b/actionview/lib/action_view/template/error.rb
index 3f38c3d2b9..4e3c02e05e 100644
--- a/actionview/lib/action_view/template/error.rb
+++ b/actionview/lib/action_view/template/error.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require "active_support/core_ext/enumerable"
 
 module ActionView
@@ -8,9 +10,6 @@ module ActionView
   class EncodingError < StandardError #:nodoc:
   end
 
-  class MissingRequestError < StandardError #:nodoc:
-  end
-
   class WrongEncodingError < EncodingError #:nodoc:
     def initialize(string, encoding)
       @string, @encoding = string, encoding
@@ -35,10 +34,10 @@ module ActionView
       prefixes = Array(prefixes)
       template_type = if partial
         "partial"
-      elsif path =~ /layouts/i
-        'layout'
+      elsif /layouts/i.match?(path)
+        "layout"
       else
-        'template'
+        "template"
       end
 
       if partial && path.present?
@@ -62,23 +61,13 @@ module ActionView
       # Override to prevent #cause resetting during re-raise.
       attr_reader :cause
 
-      def initialize(template, original_exception = nil)
-        if original_exception
-          ActiveSupport::Deprecation.warn("Passing #original_exception is deprecated and has no effect. " \
-                                          "Exceptions will automatically capture the original exception.", caller)
-        end
-
+      def initialize(template)
         super($!.message)
         set_backtrace($!.backtrace)
         @cause = $!
         @template, @sub_templates = template, nil
       end
 
-      def original_exception
-        ActiveSupport::Deprecation.warn("#original_exception is deprecated. Use #cause instead.", caller)
-        cause
-      end
-
       def file_name
         @template.identifier
       end
@@ -130,7 +119,7 @@ module ActionView
           if line_number
             "on line ##{line_number} of "
           else
-            'in '
+            "in "
           end + file_name
         end
 
diff --git a/actionview/lib/action_view/template/handlers.rb b/actionview/lib/action_view/template/handlers.rb
index ad4c353608..7ec76dcc3f 100644
--- a/actionview/lib/action_view/template/handlers.rb
+++ b/actionview/lib/action_view/template/handlers.rb
@@ -1,11 +1,13 @@
+# frozen_string_literal: true
+
 module ActionView #:nodoc:
   # = Action View Template Handlers
-  class Template
+  class Template #:nodoc:
     module Handlers #:nodoc:
-      autoload :Raw, 'action_view/template/handlers/raw'
-      autoload :ERB, 'action_view/template/handlers/erb'
-      autoload :Html, 'action_view/template/handlers/html'
-      autoload :Builder, 'action_view/template/handlers/builder'
+      autoload :Raw, "action_view/template/handlers/raw"
+      autoload :ERB, "action_view/template/handlers/erb"
+      autoload :Html, "action_view/template/handlers/html"
+      autoload :Builder, "action_view/template/handlers/builder"
 
       def self.extended(base)
         base.register_default_template_handler :raw, Raw.new
diff --git a/actionview/lib/action_view/template/handlers/builder.rb b/actionview/lib/action_view/template/handlers/builder.rb
index d90b0c6378..61492ce448 100644
--- a/actionview/lib/action_view/template/handlers/builder.rb
+++ b/actionview/lib/action_view/template/handlers/builder.rb
@@ -1,26 +1,25 @@
+# frozen_string_literal: true
+
 module ActionView
   module Template::Handlers
     class Builder
-      # Default format used by Builder.
-      class_attribute :default_format
-      self.default_format = :xml
+      class_attribute :default_format, default: :xml
 
       def call(template)
         require_engine
-        "xml = ::Builder::XmlMarkup.new(:indent => 2);" +
+        "xml = ::Builder::XmlMarkup.new(:indent => 2);" \
           "self.output_buffer = xml.target!;" +
           template.source +
           ";xml.target!;"
       end
 
-      protected
-
-      def require_engine
-        @required ||= begin
-          require "builder"
-          true
+      private
+        def require_engine # :doc:
+          @required ||= begin
+            require "builder"
+            true
+          end
         end
-      end
     end
   end
 end
diff --git a/actionview/lib/action_view/template/handlers/erb.rb b/actionview/lib/action_view/template/handlers/erb.rb
index 85a100ed4c..b7b749f9da 100644
--- a/actionview/lib/action_view/template/handlers/erb.rb
+++ b/actionview/lib/action_view/template/handlers/erb.rb
@@ -1,91 +1,20 @@
-require 'erubis'
+# frozen_string_literal: true
 
 module ActionView
   class Template
     module Handlers
-      class Erubis < ::Erubis::Eruby
-        def add_preamble(src)
-          @newline_pending = 0
-          src << "@output_buffer = output_buffer || ActionView::OutputBuffer.new;"
-        end
-
-        def add_text(src, text)
-          return if text.empty?
-
-          if text == "\n"
-            @newline_pending += 1
-          else
-            src << "@output_buffer.safe_append='"
-            src << "\n" * @newline_pending if @newline_pending > 0
-            src << escape_text(text)
-            src << "'.freeze;"
-
-            @newline_pending = 0
-          end
-        end
-
-        # Erubis toggles <%= and <%== behavior when escaping is enabled.
-        # We override to always treat <%== as escaped.
-        def add_expr(src, code, indicator)
-          case indicator
-          when '=='
-            add_expr_escaped(src, code)
-          else
-            super
-          end
-        end
-
-        BLOCK_EXPR = /\s*((\s+|\))do|\{)(\s*\|[^|]*\|)?\s*\Z/
-
-        def add_expr_literal(src, code)
-          flush_newline_if_pending(src)
-          if code =~ BLOCK_EXPR
-            src << '@output_buffer.append= ' << code
-          else
-            src << '@output_buffer.append=(' << code << ');'
-          end
-        end
-
-        def add_expr_escaped(src, code)
-          flush_newline_if_pending(src)
-          if code =~ BLOCK_EXPR
-            src << "@output_buffer.safe_expr_append= " << code
-          else
-            src << "@output_buffer.safe_expr_append=(" << code << ");"
-          end
-        end
-
-        def add_stmt(src, code)
-          flush_newline_if_pending(src)
-          super
-        end
-
-        def add_postamble(src)
-          flush_newline_if_pending(src)
-          src << '@output_buffer.to_s'
-        end
-
-        def flush_newline_if_pending(src)
-          if @newline_pending > 0
-            src << "@output_buffer.safe_append='#{"\n" * @newline_pending}'.freeze;"
-            @newline_pending = 0
-          end
-        end
-      end
-
       class ERB
+        autoload :Erubi, "action_view/template/handlers/erb/erubi"
+
         # Specify trim mode for the ERB compiler. Defaults to '-'.
         # See ERB documentation for suitable values.
-        class_attribute :erb_trim_mode
-        self.erb_trim_mode = '-'
+        class_attribute :erb_trim_mode, default: "-"
 
         # Default implementation used.
-        class_attribute :erb_implementation
-        self.erb_implementation = Erubis
+        class_attribute :erb_implementation, default: Erubi
 
         # Do not escape templates of these mime types.
-        class_attribute :escape_whitelist
-        self.escape_whitelist = ["text/plain"]
+        class_attribute :escape_whitelist, default: ["text/plain"]
 
         ENCODING_TAG = Regexp.new("\\A(<%#{ENCODING_FLAG}-?%>)[ \\t]*")
 
@@ -108,7 +37,7 @@ module ActionView
           # expression
           template_source = template.source.dup.force_encoding(Encoding::ASCII_8BIT)
 
-          erb = template_source.gsub(ENCODING_TAG, '')
+          erb = template_source.gsub(ENCODING_TAG, "")
           encoding = $2
 
           erb.force_encoding valid_encoding(template.source.dup, encoding)
@@ -118,8 +47,8 @@ module ActionView
 
           self.class.erb_implementation.new(
             erb,
-            :escape => (self.class.escape_whitelist.include? template.type),
-            :trim => (self.class.erb_trim_mode == "-")
+            escape: (self.class.escape_whitelist.include? template.type),
+            trim: (self.class.erb_trim_mode == "-")
           ).src
         end
 
diff --git a/actionview/lib/action_view/template/handlers/erb/erubi.rb b/actionview/lib/action_view/template/handlers/erb/erubi.rb
new file mode 100644
index 0000000000..db75f028ed
--- /dev/null
+++ b/actionview/lib/action_view/template/handlers/erb/erubi.rb
@@ -0,0 +1,83 @@
+# frozen_string_literal: true
+
+require "erubi"
+
+module ActionView
+  class Template
+    module Handlers
+      class ERB
+        class Erubi < ::Erubi::Engine
+          # :nodoc: all
+          def initialize(input, properties = {})
+            @newline_pending = 0
+
+            # Dup properties so that we don't modify argument
+            properties = Hash[properties]
+            properties[:preamble]   = "@output_buffer = output_buffer || ActionView::OutputBuffer.new;"
+            properties[:postamble]  = "@output_buffer.to_s"
+            properties[:bufvar]     = "@output_buffer"
+            properties[:escapefunc] = ""
+
+            super
+          end
+
+          def evaluate(action_view_erb_handler_context)
+            pr = eval("proc { #{@src} }", binding, @filename || "(erubi)")
+            action_view_erb_handler_context.instance_eval(&pr)
+          end
+
+        private
+          def add_text(text)
+            return if text.empty?
+
+            if text == "\n"
+              @newline_pending += 1
+            else
+              src << "@output_buffer.safe_append='"
+              src << "\n" * @newline_pending if @newline_pending > 0
+              src << text.gsub(/['\\]/, '\\\\\&')
+              src << "'.freeze;"
+
+              @newline_pending = 0
+            end
+          end
+
+          BLOCK_EXPR = /\s*((\s+|\))do|\{)(\s*\|[^|]*\|)?\s*\Z/
+
+          def add_expression(indicator, code)
+            flush_newline_if_pending(src)
+
+            if (indicator == "==") || @escape
+              src << "@output_buffer.safe_expr_append="
+            else
+              src << "@output_buffer.append="
+            end
+
+            if BLOCK_EXPR.match?(code)
+              src << " " << code
+            else
+              src << "(" << code << ");"
+            end
+          end
+
+          def add_code(code)
+            flush_newline_if_pending(src)
+            super
+          end
+
+          def add_postamble(_)
+            flush_newline_if_pending(src)
+            super
+          end
+
+          def flush_newline_if_pending(src)
+            if @newline_pending > 0
+              src << "@output_buffer.safe_append='#{"\n" * @newline_pending}'.freeze;"
+              @newline_pending = 0
+            end
+          end
+        end
+      end
+    end
+  end
+end
diff --git a/actionview/lib/action_view/template/handlers/html.rb b/actionview/lib/action_view/template/handlers/html.rb
index ccaa8d1469..27004a318c 100644
--- a/actionview/lib/action_view/template/handlers/html.rb
+++ b/actionview/lib/action_view/template/handlers/html.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActionView
   module Template::Handlers
     class Html < Raw
diff --git a/actionview/lib/action_view/template/handlers/raw.rb b/actionview/lib/action_view/template/handlers/raw.rb
index 760f517431..5cd23a0060 100644
--- a/actionview/lib/action_view/template/handlers/raw.rb
+++ b/actionview/lib/action_view/template/handlers/raw.rb
@@ -1,8 +1,10 @@
+# frozen_string_literal: true
+
 module ActionView
   module Template::Handlers
     class Raw
       def call(template)
-        "#{template.source.inspect};"
+        "#{template.source.inspect}.html_safe;"
       end
     end
   end
diff --git a/actionview/lib/action_view/template/html.rb b/actionview/lib/action_view/template/html.rb
index 0321f819b5..a262c6d9ad 100644
--- a/actionview/lib/action_view/template/html.rb
+++ b/actionview/lib/action_view/template/html.rb
@@ -1,6 +1,8 @@
+# frozen_string_literal: true
+
 module ActionView #:nodoc:
   # = Action View HTML Template
-  class Template
+  class Template #:nodoc:
     class HTML #:nodoc:
       attr_accessor :type
 
@@ -11,12 +13,10 @@ module ActionView #:nodoc:
       end
 
       def identifier
-        'html template'
+        "html template"
       end
 
-      def inspect
-        'html template'
-      end
+      alias_method :inspect, :identifier
 
       def to_str
         ERB::Util.h(@string)
diff --git a/actionview/lib/action_view/template/resolver.rb b/actionview/lib/action_view/template/resolver.rb
index bf68e93c58..5a86f10973 100644
--- a/actionview/lib/action_view/template/resolver.rb
+++ b/actionview/lib/action_view/template/resolver.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require "pathname"
 require "active_support/core_ext/class"
 require "active_support/core_ext/module/attribute_accessors"
@@ -14,7 +16,7 @@ module ActionView
       alias_method :partial?, :partial
 
       def self.build(name, prefix, partial)
-        virtual = ""
+        virtual = "".dup
         virtual << "#{prefix}/" unless prefix.empty?
         virtual << (partial ? "_#{name}" : name)
         new name, prefix, partial, virtual
@@ -37,15 +39,15 @@ module ActionView
     class Cache #:nodoc:
       class SmallCache < Concurrent::Map
         def initialize(options = {})
-          super(options.merge(:initial_capacity => 2))
+          super(options.merge(initial_capacity: 2))
         end
       end
 
       # preallocate all the default blocks for performance/memory consumption reasons
-      PARTIAL_BLOCK = lambda {|cache, partial| cache[partial] = SmallCache.new}
-      PREFIX_BLOCK  = lambda {|cache, prefix|  cache[prefix]  = SmallCache.new(&PARTIAL_BLOCK)}
-      NAME_BLOCK    = lambda {|cache, name|    cache[name]    = SmallCache.new(&PREFIX_BLOCK)}
-      KEY_BLOCK     = lambda {|cache, key|     cache[key]     = SmallCache.new(&NAME_BLOCK)}
+      PARTIAL_BLOCK = lambda { |cache, partial| cache[partial] = SmallCache.new }
+      PREFIX_BLOCK  = lambda { |cache, prefix|  cache[prefix]  = SmallCache.new(&PARTIAL_BLOCK) }
+      NAME_BLOCK    = lambda { |cache, name|    cache[name]    = SmallCache.new(&PREFIX_BLOCK) }
+      KEY_BLOCK     = lambda { |cache, key|     cache[key]     = SmallCache.new(&NAME_BLOCK) }
 
       # usually a majority of template look ups return nothing, use this canonical preallocated array to save memory
       NO_TEMPLATES = [].freeze
@@ -107,26 +109,25 @@ module ActionView
 
       private
 
-      def canonical_no_templates(templates)
-        templates.empty? ? NO_TEMPLATES : templates
-      end
-
-      def templates_have_changed?(cached_templates, fresh_templates)
-        # if either the old or new template list is empty, we don't need to (and can't)
-        # compare modification times, and instead just check whether the lists are different
-        if cached_templates.blank? || fresh_templates.blank?
-          return fresh_templates.blank? != cached_templates.blank?
+        def canonical_no_templates(templates)
+          templates.empty? ? NO_TEMPLATES : templates
         end
 
-        cached_templates_max_updated_at = cached_templates.map(&:updated_at).max
+        def templates_have_changed?(cached_templates, fresh_templates)
+          # if either the old or new template list is empty, we don't need to (and can't)
+          # compare modification times, and instead just check whether the lists are different
+          if cached_templates.blank? || fresh_templates.blank?
+            return fresh_templates.blank? != cached_templates.blank?
+          end
+
+          cached_templates_max_updated_at = cached_templates.map(&:updated_at).max
 
-        # if a template has changed, it will be now be newer than all the cached templates
-        fresh_templates.any? { |t| t.updated_at > cached_templates_max_updated_at }
-      end
+          # if a template has changed, it will be now be newer than all the cached templates
+          fresh_templates.any? { |t| t.updated_at > cached_templates_max_updated_at }
+        end
     end
 
-    cattr_accessor :caching
-    self.caching = true
+    cattr_accessor :caching, default: true
 
     class << self
       alias :caching? :caching
@@ -141,13 +142,13 @@ module ActionView
     end
 
     # Normalizes the arguments and passes it on to find_templates.
-    def find_all(name, prefix=nil, partial=false, details={}, key=nil, locals=[])
+    def find_all(name, prefix = nil, partial = false, details = {}, key = nil, locals = [])
       cached(key, [name, prefix, partial], details, locals) do
         find_templates(name, prefix, partial, details)
       end
     end
 
-    def find_all_anywhere(name, prefix, partial=false, details={}, key=nil, locals=[])
+    def find_all_anywhere(name, prefix, partial = false, details = {}, key = nil, locals = [])
       cached(key, [name, prefix, partial], details, locals) do
         find_templates(name, prefix, partial, details, true)
       end
@@ -164,8 +165,8 @@ module ActionView
     # This is what child classes implement. No defaults are needed
     # because Resolver guarantees that the arguments are present and
     # normalized.
-    def find_templates(name, prefix, partial, details)
-      raise NotImplementedError, "Subclasses must implement a find_templates(name, prefix, partial, details) method"
+    def find_templates(name, prefix, partial, details, outside_app_allowed = false)
+      raise NotImplementedError, "Subclasses must implement a find_templates(name, prefix, partial, details, outside_app_allowed = false) method"
     end
 
     # Helpers that builds a path. Useful for building virtual paths.
@@ -177,7 +178,7 @@ module ActionView
     # always check the cache before hitting the resolver. Otherwise,
     # it always hits the resolver but if the key is present, check if the
     # resolver is fresher before returning it.
-    def cached(key, path_info, details, locals) #:nodoc:
+    def cached(key, path_info, details, locals)
       name, prefix, partial = path_info
       locals = locals.map(&:to_s).sort!
 
@@ -191,7 +192,7 @@ module ActionView
     end
 
     # Ensures all the resolver information is set in the template.
-    def decorate(templates, path_info, details, locals) #:nodoc:
+    def decorate(templates, path_info, details, locals)
       cached = nil
       templates.each do |t|
         t.locals         = locals
@@ -204,103 +205,103 @@ module ActionView
 
   # An abstract class that implements a Resolver with path semantics.
   class PathResolver < Resolver #:nodoc:
-    EXTENSIONS = { :locale => ".", :formats => ".", :variants => "+", :handlers => "." }
+    EXTENSIONS = { locale: ".", formats: ".", variants: "+", handlers: "." }
     DEFAULT_PATTERN = ":prefix/:action{.:locale,}{.:formats,}{+:variants,}{.:handlers,}"
 
-    def initialize(pattern=nil)
+    def initialize(pattern = nil)
       @pattern = pattern || DEFAULT_PATTERN
       super()
     end
 
     private
 
-    def find_templates(name, prefix, partial, details, outside_app_allowed = false)
-      path = Path.build(name, prefix, partial)
-      query(path, details, details[:formats], outside_app_allowed)
-    end
+      def find_templates(name, prefix, partial, details, outside_app_allowed = false)
+        path = Path.build(name, prefix, partial)
+        query(path, details, details[:formats], outside_app_allowed)
+      end
 
-    def query(path, details, formats, outside_app_allowed)
-      query = build_query(path, details)
+      def query(path, details, formats, outside_app_allowed)
+        query = build_query(path, details)
 
-      template_paths = find_template_paths(query)
-      template_paths = reject_files_external_to_app(template_paths) unless outside_app_allowed
+        template_paths = find_template_paths(query)
+        template_paths = reject_files_external_to_app(template_paths) unless outside_app_allowed
 
-      template_paths.map do |template|
-        handler, format, variant = extract_handler_and_format_and_variant(template, formats)
-        contents = File.binread(template)
+        template_paths.map do |template|
+          handler, format, variant = extract_handler_and_format_and_variant(template)
+          contents = File.binread(template)
 
-        Template.new(contents, File.expand_path(template), handler,
-          :virtual_path => path.virtual,
-          :format       => format,
-          :variant      => variant,
-          :updated_at   => mtime(template)
-        )
+          Template.new(contents, File.expand_path(template), handler,
+            virtual_path: path.virtual,
+            format: format,
+            variant: variant,
+            updated_at: mtime(template)
+          )
+        end
       end
-    end
 
-    def reject_files_external_to_app(files)
-      files.reject { |filename| !inside_path?(@path, filename) }
-    end
+      def reject_files_external_to_app(files)
+        files.reject { |filename| !inside_path?(@path, filename) }
+      end
 
-    def find_template_paths(query)
-      Dir[query].uniq.reject do |filename|
-        File.directory?(filename) ||
-          # deals with case-insensitive file systems.
-          !File.fnmatch(query, filename, File::FNM_EXTGLOB)
+      def find_template_paths(query)
+        Dir[query].uniq.reject do |filename|
+          File.directory?(filename) ||
+            # deals with case-insensitive file systems.
+            !File.fnmatch(query, filename, File::FNM_EXTGLOB)
+        end
       end
-    end
 
-    def inside_path?(path, filename)
-      filename = File.expand_path(filename)
-      path = File.join(path, '')
-      filename.start_with?(path)
-    end
+      def inside_path?(path, filename)
+        filename = File.expand_path(filename)
+        path = File.join(path, "")
+        filename.start_with?(path)
+      end
 
-    # Helper for building query glob string based on resolver's pattern.
-    def build_query(path, details)
-      query = @pattern.dup
+      # Helper for building query glob string based on resolver's pattern.
+      def build_query(path, details)
+        query = @pattern.dup
 
-      prefix = path.prefix.empty? ? '' : "#{escape_entry(path.prefix)}\\1"
-      query.gsub!(/:prefix(\/)?/, prefix)
+        prefix = path.prefix.empty? ? "" : "#{escape_entry(path.prefix)}\\1"
+        query.gsub!(/:prefix(\/)?/, prefix)
 
-      partial = escape_entry(path.partial? ? "_#{path.name}" : path.name)
-      query.gsub!(/:action/, partial)
+        partial = escape_entry(path.partial? ? "_#{path.name}" : path.name)
+        query.gsub!(/:action/, partial)
 
-      details.each do |ext, candidates|
-        if ext == :variants && candidates == :any
-          query.gsub!(/:#{ext}/, "*")
-        else
-          query.gsub!(/:#{ext}/, "{#{candidates.compact.uniq.join(',')}}")
+        details.each do |ext, candidates|
+          if ext == :variants && candidates == :any
+            query.gsub!(/:#{ext}/, "*")
+          else
+            query.gsub!(/:#{ext}/, "{#{candidates.compact.uniq.join(',')}}")
+          end
         end
-      end
 
-      File.expand_path(query, @path)
-    end
+        File.expand_path(query, @path)
+      end
 
-    def escape_entry(entry)
-      entry.gsub(/[*?{}\[\]]/, '\\\\\\&'.freeze)
-    end
+      def escape_entry(entry)
+        entry.gsub(/[*?{}\[\]]/, '\\\\\\&'.freeze)
+      end
 
-    # Returns the file mtime from the filesystem.
-    def mtime(p)
-      File.mtime(p)
-    end
+      # Returns the file mtime from the filesystem.
+      def mtime(p)
+        File.mtime(p)
+      end
 
-    # Extract handler, formats and variant from path. If a format cannot be found neither
-    # from the path, or the handler, we should return the array of formats given
-    # to the resolver.
-    def extract_handler_and_format_and_variant(path, default_formats)
-      pieces = File.basename(path).split('.'.freeze)
-      pieces.shift
+      # Extract handler, formats and variant from path. If a format cannot be found neither
+      # from the path, or the handler, we should return the array of formats given
+      # to the resolver.
+      def extract_handler_and_format_and_variant(path)
+        pieces = File.basename(path).split(".".freeze)
+        pieces.shift
 
-      extension = pieces.pop
+        extension = pieces.pop
 
-      handler = Template.handler_for_extension(extension)
-      format, variant = pieces.last.split(EXTENSIONS[:variants], 2) if pieces.last
-      format  &&= Template::Types[format]
+        handler = Template.handler_for_extension(extension)
+        format, variant = pieces.last.split(EXTENSIONS[:variants], 2) if pieces.last
+        format &&= Template::Types[format]
 
-      [handler, format, variant]
-    end
+        [handler, format, variant]
+      end
   end
 
   # A resolver that loads files from the filesystem. It allows setting your own
@@ -309,13 +310,13 @@ module ActionView
   # ==== Examples
   #
   # Default pattern, loads views the same way as previous versions of rails, eg. when you're
-  # looking for `users/new` it will produce query glob: `users/new{.{en},}{.{html,js},}{.{erb,haml},}`
+  # looking for <tt>users/new</tt> it will produce query glob: <tt>users/new{.{en},}{.{html,js},}{.{erb,haml},}</tt>
   #
   #   FileSystemResolver.new("/path/to/views", ":prefix/:action{.:locale,}{.:formats,}{+:variants,}{.:handlers,}")
   #
   # This one allows you to keep files with different formats in separate subdirectories,
-  # eg. `users/new.html` will be loaded from `users/html/new.erb` or `users/new.html.erb`,
-  # `users/new.js` from `users/js/new.erb` or `users/new.js.erb`, etc.
+  # eg. <tt>users/new.html</tt> will be loaded from <tt>users/html/new.erb</tt> or <tt>users/new.html.erb</tt>,
+  # <tt>users/new.js</tt> from <tt>users/js/new.erb</tt> or <tt>users/new.js.erb</tt>, etc.
   #
   #   FileSystemResolver.new("/path/to/views", ":prefix/{:formats/,}:action{.:locale,}{.:formats,}{+:variants,}{.:handlers,}")
   #
@@ -342,7 +343,7 @@ module ActionView
   # * <tt>:handlers</tt> - possible handlers (for example erb, haml, builder...)
   #
   class FileSystemResolver < PathResolver
-    def initialize(path, pattern=nil)
+    def initialize(path, pattern = nil)
       raise ArgumentError, "path already is a Resolver class" if path.is_a?(Resolver)
       super(pattern)
       @path = File.expand_path(path)
diff --git a/actionview/lib/action_view/template/text.rb b/actionview/lib/action_view/template/text.rb
index 04f5b8d17a..f8d6c2811f 100644
--- a/actionview/lib/action_view/template/text.rb
+++ b/actionview/lib/action_view/template/text.rb
@@ -1,22 +1,21 @@
+# frozen_string_literal: true
+
 module ActionView #:nodoc:
   # = Action View Text Template
-  class Template
+  class Template #:nodoc:
     class Text #:nodoc:
       attr_accessor :type
 
-      def initialize(string, type = nil)
+      def initialize(string)
         @string = string.to_s
-        @type   = Types[type] || type if type
-        @type ||= Types[:text]
+        @type = Types[:text]
       end
 
       def identifier
-        'text template'
+        "text template"
       end
 
-      def inspect
-        'text template'
-      end
+      alias_method :inspect, :identifier
 
       def to_str
         @string
@@ -27,7 +26,7 @@ module ActionView #:nodoc:
       end
 
       def formats
-        [@type.respond_to?(:ref) ? @type.ref : @type.to_s]
+        [@type.ref]
       end
     end
   end
diff --git a/actionview/lib/action_view/template/types.rb b/actionview/lib/action_view/template/types.rb
index b32567cd66..67b7a62de6 100644
--- a/actionview/lib/action_view/template/types.rb
+++ b/actionview/lib/action_view/template/types.rb
@@ -1,7 +1,9 @@
-require 'active_support/core_ext/module/attribute_accessors'
+# frozen_string_literal: true
+
+require "active_support/core_ext/module/attribute_accessors"
 
 module ActionView
-  class Template
+  class Template #:nodoc:
     class Types
       class Type
         SET = Struct.new(:symbols).new([ :html, :text, :js, :css, :xml, :json ])
diff --git a/actionview/lib/action_view/test_case.rb b/actionview/lib/action_view/test_case.rb
index 120962b5aa..e1cbae5845 100644
--- a/actionview/lib/action_view/test_case.rb
+++ b/actionview/lib/action_view/test_case.rb
@@ -1,9 +1,11 @@
-require 'active_support/core_ext/module/remove_method'
-require 'action_controller'
-require 'action_controller/test_case'
-require 'action_view'
+# frozen_string_literal: true
 
-require 'rails-dom-testing'
+require "active_support/core_ext/module/redefine_method"
+require "action_controller"
+require "action_controller/test_case"
+require "action_view"
+
+require "rails-dom-testing"
 
 module ActionView
   # = Action View Test Case
@@ -18,16 +20,16 @@ module ActionView
       end
 
       def controller_path=(path)
-        self.class.controller_path=(path)
+        self.class.controller_path = (path)
       end
 
       def initialize
         super
         self.class.controller_path = ""
-        @request = ActionController::TestRequest.create
+        @request = ActionController::TestRequest.create(self.class)
         @response = ActionDispatch::TestResponse.new
 
-        @request.env.delete('PATH_INFO')
+        @request.env.delete("PATH_INFO")
         @params = ActionController::Parameters.new
       end
     end
@@ -49,7 +51,7 @@ module ActionView
 
       include ActiveSupport::Testing::ConstantLookup
 
-      delegate :lookup_context, :to => :controller
+      delegate :lookup_context, to: :controller
       attr_accessor :controller, :output_buffer, :rendered
 
       module ClassMethods
@@ -71,7 +73,7 @@ module ActionView
         def helper_method(*methods)
           # Almost a duplicate from ActionController::Helpers
           methods.flatten.each do |method|
-            _helpers.module_eval <<-end_eval
+            _helpers.module_eval <<-end_eval, __FILE__, __LINE__ + 1
               def #{method}(*args, &block)                    # def current_user(*args, &block)
                 _test_case.send(%(#{method}), *args, &block)  #   _test_case.send(%(current_user), *args, &block)
               end                                             # end
@@ -96,16 +98,16 @@ module ActionView
           helper(helper_class) if helper_class
           include _helpers
         end
-
       end
 
       def setup_with_controller
         @controller = ActionView::TestCase::TestController.new
         @request = @controller.request
+        @view_flow = ActionView::OutputFlow.new
         # empty string ensures buffer has UTF-8 encoding as
         # new without arguments returns ASCII-8BIT encoded buffer like String#new
-        @output_buffer = ActiveSupport::SafeBuffer.new ''
-        @rendered = ''
+        @output_buffer = ActiveSupport::SafeBuffer.new ""
+        @rendered = "".dup
 
         make_test_case_available_to_view!
         say_no_to_protect_against_forgery!
@@ -125,6 +127,10 @@ module ActionView
         @_rendered_views ||= RenderedViewsCollection.new
       end
 
+      def _routes
+        @controller._routes if @controller.respond_to?(:_routes)
+      end
+
       # Need to experiment if this priority is the best one: rendered => output_buffer
       class RenderedViewsCollection
         def initialize
@@ -146,13 +152,14 @@ module ActionView
 
         def view_rendered?(view, expected_locals)
           locals_for(view).any? do |actual_locals|
-            expected_locals.all? {|key, value| value == actual_locals[key] }
+            expected_locals.all? { |key, value| value == actual_locals[key] }
           end
         end
       end
 
       included do
         setup :setup_with_controller
+        ActiveSupport.run_load_hooks(:action_view_test_case, self)
       end
 
     private
@@ -164,7 +171,7 @@ module ActionView
 
       def say_no_to_protect_against_forgery!
         _helpers.module_eval do
-          remove_possible_method :protect_against_forgery?
+          silence_redefinition_of_method :protect_against_forgery?
           def protect_against_forgery?
             false
           end
@@ -206,8 +213,8 @@ module ActionView
           view = @controller.view_context
           view.singleton_class.include(_helpers)
           view.extend(Locals)
-          view.rendered_views = self.rendered_views
-          view.output_buffer = self.output_buffer
+          view.rendered_views = rendered_views
+          view.output_buffer = output_buffer
           view
         end
       end
@@ -240,6 +247,7 @@ module ActionView
         :@test_passed,
         :@view,
         :@view_context_class,
+        :@view_flow,
         :@_subscribers,
         :@html_document
       ]
@@ -258,25 +266,33 @@ module ActionView
         end]
       end
 
-      def _routes
-        @controller._routes if @controller.respond_to?(:_routes)
-      end
-
       def method_missing(selector, *args)
         begin
           routes = @controller.respond_to?(:_routes) && @controller._routes
         rescue
-          # Dont call routes, if there is an error on _routes call
+          # Don't call routes, if there is an error on _routes call
         end
 
         if routes &&
-           ( routes.named_routes.route_defined?(selector) ||
-             routes.mounted_helpers.method_defined?(selector) )
+           (routes.named_routes.route_defined?(selector) ||
+             routes.mounted_helpers.method_defined?(selector))
           @controller.__send__(selector, *args)
         else
           super
         end
       end
+
+      def respond_to_missing?(name, include_private = false)
+        begin
+          routes = @controller.respond_to?(:_routes) && @controller._routes
+        rescue
+          # Don't call routes, if there is an error on _routes call
+        end
+
+        routes &&
+          (routes.named_routes.route_defined?(name) ||
+           routes.mounted_helpers.method_defined?(name))
+      end
     end
 
     include Behavior
diff --git a/actionview/lib/action_view/testing/resolvers.rb b/actionview/lib/action_view/testing/resolvers.rb
index 2664aca991..68186c3bf8 100644
--- a/actionview/lib/action_view/testing/resolvers.rb
+++ b/actionview/lib/action_view/testing/resolvers.rb
@@ -1,4 +1,6 @@
-require 'action_view/template/resolver'
+# frozen_string_literal: true
+
+require "action_view/template/resolver"
 
 module ActionView #:nodoc:
   # Use FixtureResolver in your tests to simulate the presence of files on the
@@ -8,46 +10,45 @@ module ActionView #:nodoc:
   class FixtureResolver < PathResolver
     attr_reader :hash
 
-    def initialize(hash = {}, pattern=nil)
+    def initialize(hash = {}, pattern = nil)
       super(pattern)
       @hash = hash
     end
 
     def to_s
-      @hash.keys.join(', ')
+      @hash.keys.join(", ")
     end
 
-  private
-
-    def query(path, exts, formats, _)
-      query = ""
-      EXTENSIONS.each_key do |ext|
-        query << '(' << exts[ext].map {|e| e && Regexp.escape(".#{e}") }.join('|') << '|)'
-      end
-      query = /^(#{Regexp.escape(path)})#{query}$/
-
-      templates = []
-      @hash.each do |_path, array|
-        source, updated_at = array
-        next unless _path =~ query
-        handler, format, variant = extract_handler_and_format_and_variant(_path, formats)
-        templates << Template.new(source, _path, handler,
-          :virtual_path => path.virtual,
-          :format => format,
-          :variant => variant,
-          :updated_at => updated_at
-        )
+    private
+
+      def query(path, exts, _, _)
+        query = "".dup
+        EXTENSIONS.each_key do |ext|
+          query << "(" << exts[ext].map { |e| e && Regexp.escape(".#{e}") }.join("|") << "|)"
+        end
+        query = /^(#{Regexp.escape(path)})#{query}$/
+
+        templates = []
+        @hash.each do |_path, array|
+          source, updated_at = array
+          next unless query.match?(_path)
+          handler, format, variant = extract_handler_and_format_and_variant(_path)
+          templates << Template.new(source, _path, handler,
+            virtual_path: path.virtual,
+            format: format,
+            variant: variant,
+            updated_at: updated_at
+          )
+        end
+
+        templates.sort_by { |t| -t.identifier.match(/^#{query}$/).captures.reject(&:blank?).size }
       end
-
-      templates.sort_by {|t| -t.identifier.match(/^#{query}$/).captures.reject(&:blank?).size }
-    end
   end
 
   class NullResolver < PathResolver
-    def query(path, exts, formats, _)
-      handler, format, variant = extract_handler_and_format_and_variant(path, formats)
-      [ActionView::Template.new("Template generated by Null Resolver", path.virtual, handler, :virtual_path => path.virtual, :format => format, :variant => variant)]
+    def query(path, exts, _, _)
+      handler, format, variant = extract_handler_and_format_and_variant(path)
+      [ActionView::Template.new("Template generated by Null Resolver", path.virtual, handler, virtual_path: path.virtual, format: format, variant: variant)]
     end
   end
 end
-
diff --git a/actionview/lib/action_view/version.rb b/actionview/lib/action_view/version.rb
index f55d3fdaef..be53797a14 100644
--- a/actionview/lib/action_view/version.rb
+++ b/actionview/lib/action_view/version.rb
@@ -1,4 +1,6 @@
-require_relative 'gem_version'
+# frozen_string_literal: true
+
+require_relative "gem_version"
 
 module ActionView
   # Returns the version of the currently loaded ActionView as a <tt>Gem::Version</tt>
diff --git a/actionview/lib/action_view/view_paths.rb b/actionview/lib/action_view/view_paths.rb
index 717d6866c5..d5694d77f4 100644
--- a/actionview/lib/action_view/view_paths.rb
+++ b/actionview/lib/action_view/view_paths.rb
@@ -1,15 +1,15 @@
+# frozen_string_literal: true
+
 module ActionView
   module ViewPaths
     extend ActiveSupport::Concern
 
     included do
-      class_attribute :_view_paths
-      self._view_paths = ActionView::PathSet.new
-      self._view_paths.freeze
+      class_attribute :_view_paths, default: ActionView::PathSet.new.freeze
     end
 
     delegate :template_exists?, :any_templates?, :view_paths, :formats, :formats=,
-             :locale, :locale=, :to => :lookup_context
+             :locale, :locale=, to: :lookup_context
 
     module ClassMethods
       def _prefixes # :nodoc:
@@ -22,11 +22,11 @@ module ActionView
 
       private
 
-      # Override this method in your controller if you want to change paths prefixes for finding views.
-      # Prefixes defined here will still be added to parents' <tt>._prefixes</tt>.
-      def local_prefixes
-        [controller_path]
-      end
+        # Override this method in your controller if you want to change paths prefixes for finding views.
+        # Prefixes defined here will still be added to parents' <tt>._prefixes</tt>.
+        def local_prefixes
+          [controller_path]
+        end
     end
 
     # The prefixes used in render "foo" shortcuts.
@@ -43,13 +43,25 @@ module ActionView
     end
 
     def details_for_lookup
-      { }
+      {}
     end
 
+    # Append a path to the list of view paths for the current <tt>LookupContext</tt>.
+    #
+    # ==== Parameters
+    # * <tt>path</tt> - If a String is provided, it gets converted into
+    #   the default view path. You may also provide a custom view path
+    #   (see ActionView::PathSet for more information)
     def append_view_path(path)
       lookup_context.view_paths.push(*path)
     end
 
+    # Prepend a path to the list of view paths for the current <tt>LookupContext</tt>.
+    #
+    # ==== Parameters
+    # * <tt>path</tt> - If a String is provided, it gets converted into
+    #   the default view path. You may also provide a custom view path
+    #   (see ActionView::PathSet for more information)
     def prepend_view_path(path)
       lookup_context.view_paths.unshift(*path)
     end
diff --git a/actionview/package.json b/actionview/package.json
new file mode 100644
index 0000000000..787ae06208
--- /dev/null
+++ b/actionview/package.json
@@ -0,0 +1,36 @@
+{
+  "name": "rails-ujs",
+  "version": "5.2.0-beta2",
+  "description": "Ruby on Rails unobtrusive scripting adapter",
+  "main": "lib/assets/compiled/rails-ujs.js",
+  "files": [
+    "lib/assets/compiled/*.js"
+  ],
+  "directories": {
+    "test": "test"
+  },
+  "scripts": {
+    "build": "bundle exec blade build",
+    "test": "echo \"See the README: https://github.com/rails/rails/blob/master/actionview/app/assets/javascripts#how-to-run-tests\" && exit 1",
+    "lint": "coffeelint app/assets/javascripts && eslint test/ujs/public/test"
+  },
+  "repository": {
+    "type": "git",
+    "url": "rails/rails"
+  },
+  "contributors": [
+    "Stephen St. Martin",
+    "Steve Schwartz",
+    "Dangyi Liu",
+    "All contributors"
+  ],
+  "license": "MIT",
+  "bugs": {
+    "url": "https://github.com/rails/rails/issues"
+  },
+  "homepage": "http://rubyonrails.org/",
+  "devDependencies": {
+    "coffeelint": "^1.15.7",
+    "eslint": "^2.13.1"
+  }
+}
diff --git a/actionview/test/abstract_unit.rb b/actionview/test/abstract_unit.rb
index 3256d8fc4d..f20a66c2d2 100644
--- a/actionview/test/abstract_unit.rb
+++ b/actionview/test/abstract_unit.rb
@@ -1,36 +1,30 @@
-$:.unshift(File.dirname(__FILE__) + '/lib')
-$:.unshift(File.dirname(__FILE__) + '/fixtures/helpers')
-$:.unshift(File.dirname(__FILE__) + '/fixtures/alternate_helpers')
+# frozen_string_literal: true
 
-ENV['TMPDIR'] = File.join(File.dirname(__FILE__), 'tmp')
+$:.unshift File.expand_path("lib", __dir__)
+$:.unshift File.expand_path("fixtures/helpers", __dir__)
+$:.unshift File.expand_path("fixtures/alternate_helpers", __dir__)
 
-require 'active_support/core_ext/kernel/reporting'
+ENV["TMPDIR"] = File.expand_path("tmp", __dir__)
+
+require "active_support/core_ext/kernel/reporting"
 
 # These are the normal settings that will be set up by Railties
 # TODO: Have these tests support other combinations of these values
 silence_warnings do
-  Encoding.default_internal = "UTF-8"
-  Encoding.default_external = "UTF-8"
+  Encoding.default_internal = Encoding::UTF_8
+  Encoding.default_external = Encoding::UTF_8
 end
 
-require 'active_support/testing/autorun'
-require 'active_support/testing/method_call_assertions'
-require 'action_controller'
-require 'action_view'
-require 'action_view/testing/resolvers'
-require 'active_support/dependencies'
-require 'active_model'
-require 'active_record'
-
-require 'pp' # require 'pp' early to prevent hidden_methods from not picking up the pretty-print methods until too late
-
-module Rails
-  class << self
-    def env
-      @_env ||= ActiveSupport::StringInquirer.new(ENV["RAILS_ENV"] || ENV["RACK_ENV"] || "test")
-    end
-  end
-end
+require "active_support/testing/autorun"
+require "active_support/testing/method_call_assertions"
+require "action_controller"
+require "action_view"
+require "action_view/testing/resolvers"
+require "active_support/dependencies"
+require "active_model"
+require "active_record"
+
+require "pp" # require 'pp' early to prevent hidden_methods from not picking up the pretty-print methods until too late
 
 ActiveSupport::Dependencies.hook!
 
@@ -43,11 +37,11 @@ ActiveSupport::Deprecation.debug = true
 I18n.enforce_available_locales = false
 
 # Register danish language for testing
-I18n.backend.store_translations 'da', {}
-I18n.backend.store_translations 'pt-BR', {}
+I18n.backend.store_translations "da", {}
+I18n.backend.store_translations "pt-BR", {}
 ORIGINAL_LOCALES = I18n.available_locales.map(&:to_s).sort
 
-FIXTURE_LOAD_PATH = File.join(File.dirname(__FILE__), 'fixtures')
+FIXTURE_LOAD_PATH = File.expand_path("fixtures", __dir__)
 
 module RenderERBUtils
   def view
@@ -95,11 +89,11 @@ module ActionDispatch
 
       ActiveSupport::Deprecation.silence do
         SharedTestRoutes.draw do
-          get ':controller(/:action)'
+          get ":controller(/:action)"
         end
 
         ActionDispatch::IntegrationTest.app.routes.draw do
-          get ':controller(/:action)'
+          get ":controller(/:action)"
         end
       end
 
@@ -108,12 +102,6 @@ module ActionDispatch
   end
 end
 
-module ActiveSupport
-  class TestCase
-    include ActionDispatch::DrawOnce
-  end
-end
-
 class RoutedRackApp
   attr_reader :routes
 
@@ -133,11 +121,11 @@ class BasicController
   def config
     @config ||= ActiveSupport::InheritableOptions.new(ActionController::Base.config).tap do |config|
       # VIEW TODO: View tests should not require a controller
-      public_dir = File.expand_path("../fixtures/public", __FILE__)
+      public_dir = File.expand_path("fixtures/public", __dir__)
       config.assets_dir = public_dir
       config.javascripts_dir = "#{public_dir}/javascripts"
       config.stylesheets_dir = "#{public_dir}/stylesheets"
-      config.assets          = ActiveSupport::InheritableOptions.new({ :prefix => "assets" })
+      config.assets          = ActiveSupport::InheritableOptions.new(prefix: "assets")
       config
     end
   end
@@ -160,29 +148,6 @@ class ActionDispatch::IntegrationTest < ActiveSupport::TestCase
 
   self.app = build_app
 
-  # Stub Rails dispatcher so it does not get controller references and
-  # simply return the controller#action as Rack::Body.
-  class StubDispatcher < ::ActionDispatch::Routing::RouteSet::Dispatcher
-    protected
-    def controller_reference(controller_param)
-      controller_param
-    end
-
-    def dispatch(controller, action, env)
-      [200, {'Content-Type' => 'text/html'}, ["#{controller}##{action}"]]
-    end
-  end
-
-  def self.stub_controllers
-    old_dispatcher = ActionDispatch::Routing::RouteSet::Dispatcher
-    ActionDispatch::Routing::RouteSet.module_eval { remove_const :Dispatcher }
-    ActionDispatch::Routing::RouteSet.module_eval { const_set :Dispatcher, StubDispatcher }
-    yield ActionDispatch::Routing::RouteSet.new
-  ensure
-    ActionDispatch::Routing::RouteSet.module_eval { remove_const :Dispatcher }
-    ActionDispatch::Routing::RouteSet.module_eval { const_set :Dispatcher, old_dispatcher }
-  end
-
   def with_routing(&block)
     temporary_routes = ActionDispatch::Routing::RouteSet.new
     old_app, self.class.app = self.class.app, self.class.build_app(temporary_routes)
@@ -194,21 +159,6 @@ class ActionDispatch::IntegrationTest < ActiveSupport::TestCase
     self.class.app = old_app
     silence_warnings { Object.const_set(:SharedTestRoutes, old_routes) }
   end
-
-  def with_autoload_path(path)
-    path = File.join(File.dirname(__FILE__), "fixtures", path)
-    if ActiveSupport::Dependencies.autoload_paths.include?(path)
-      yield
-    else
-      begin
-        ActiveSupport::Dependencies.autoload_paths << path
-        yield
-      ensure
-        ActiveSupport::Dependencies.autoload_paths.reject! {|p| p == path}
-        ActiveSupport::Dependencies.clear
-      end
-    end
-  end
 end
 
 ActionView::RoutingUrlFor.include(ActionDispatch::Routing::UrlFor)
@@ -263,23 +213,24 @@ end
 module ActionDispatch
   class DebugExceptions
     private
-    remove_method :stderr_logger
-    # Silence logger
-    def stderr_logger
-      nil
-    end
+      remove_method :stderr_logger
+      # Silence logger
+      def stderr_logger
+        nil
+      end
   end
 end
 
-# Skips the current run on Rubinius using Minitest::Assertions#skip
-def rubinius_skip(message = '')
-  skip message if RUBY_ENGINE == 'rbx'
-end
-# Skips the current run on JRuby using Minitest::Assertions#skip
-def jruby_skip(message = '')
-  skip message if defined?(JRUBY_VERSION)
-end
-
 class ActiveSupport::TestCase
+  include ActionDispatch::DrawOnce
   include ActiveSupport::Testing::MethodCallAssertions
+
+  # Skips the current run on Rubinius using Minitest::Assertions#skip
+  private def rubinius_skip(message = "")
+    skip message if RUBY_ENGINE == "rbx"
+  end
+  # Skips the current run on JRuby using Minitest::Assertions#skip
+  private def jruby_skip(message = "")
+    skip message if defined?(JRUBY_VERSION)
+  end
 end
diff --git a/actionview/test/actionpack/abstract/abstract_controller_test.rb b/actionview/test/actionpack/abstract/abstract_controller_test.rb
index 490932fef0..4d4e2b8ef2 100644
--- a/actionview/test/actionpack/abstract/abstract_controller_test.rb
+++ b/actionview/test/actionpack/abstract/abstract_controller_test.rb
@@ -1,9 +1,10 @@
-require 'abstract_unit'
-require 'set'
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "set"
 
 module AbstractController
   module Testing
-
     # Test basic dispatching.
     # ====
     # * Call process
@@ -38,12 +39,12 @@ module AbstractController
 
       def render(options = {})
         if options.is_a?(String)
-          options = {:_template_name => options}
+          options = { _template_name: options }
         end
         super
       end
 
-      append_view_path File.expand_path(File.join(File.dirname(__FILE__), "views"))
+      append_view_path File.expand_path("views", __dir__)
     end
 
     class Me2 < RenderingController
@@ -65,11 +66,11 @@ module AbstractController
       end
 
       def rendering_to_body
-        self.response_body = render_to_body :template => "naked_render"
+        self.response_body = render_to_body template: "naked_render"
       end
 
       def rendering_to_string
-        self.response_body = render_to_string :template => "naked_render"
+        self.response_body = render_to_string template: "naked_render"
       end
     end
 
@@ -114,13 +115,13 @@ module AbstractController
     # * self._prefix is used when defined
     class PrefixedViews < RenderingController
       private
-      def self.prefix
-        name.underscore
-      end
+        def self.prefix
+          name.underscore
+        end
 
-      def _prefixes
-        [self.class.prefix]
-      end
+        def _prefixes
+          [self.class.prefix]
+        end
     end
 
     class Me3 < PrefixedViews
@@ -153,7 +154,7 @@ module AbstractController
     class OverridingLocalPrefixes < AbstractController::Base
       include AbstractController::Rendering
       include ActionView::Rendering
-      append_view_path File.expand_path(File.join(File.dirname(__FILE__), "views"))
+      append_view_path File.expand_path("views", __dir__)
 
       def index
         render
@@ -189,19 +190,19 @@ module AbstractController
       include ActionView::Layouts
 
       private
-      def self.layout(formats)
-        find_template(name.underscore, {:formats => formats}, :_prefixes => ["layouts"])
-      rescue ActionView::MissingTemplate
-        begin
-          find_template("application", {:formats => formats}, :_prefixes => ["layouts"])
+        def self.layout(formats)
+          find_template(name.underscore, { formats: formats }, { _prefixes: ["layouts"] })
         rescue ActionView::MissingTemplate
+          begin
+            find_template("application", { formats: formats }, { _prefixes: ["layouts"] })
+          rescue ActionView::MissingTemplate
+          end
         end
-      end
 
-      def render_to_body(options = {})
-        options[:_layout] = options[:layout] || _default_layout({})
-        super
-      end
+        def render_to_body(options = {})
+          options[:_layout] = options[:layout] || _default_layout({})
+          super
+        end
     end
 
     class Me4 < WithLayouts
@@ -228,14 +229,14 @@ module AbstractController
     end
 
     class ActionMissingRespondToActionController < AbstractController::Base
-      # No actions
+    # No actions
     private
       def action_missing(action_name)
         self.response_body = "success"
       end
     end
 
-    class RespondToActionController < AbstractController::Base;
+    class RespondToActionController < AbstractController::Base
       def index() self.response_body = "success" end
 
       def fail()  self.response_body = "fail"    end
@@ -248,7 +249,6 @@ module AbstractController
     end
 
     class TestRespondToAction < ActiveSupport::TestCase
-
       def assert_dispatch(klass, body = "success", action = :index)
         controller = klass.new
         controller.process(action)
@@ -277,18 +277,16 @@ module AbstractController
     end
 
     class Me6 < AbstractController::Base
-      self.action_methods
+      action_methods
 
       def index
       end
     end
 
     class TestActionMethodsReloading < ActiveSupport::TestCase
-
       test "action_methods should be reloaded after defining a new method" do
         assert_equal Set.new(["index"]), Me6.action_methods
       end
     end
-
   end
 end
diff --git a/actionview/test/actionpack/abstract/helper_test.rb b/actionview/test/actionpack/abstract/helper_test.rb
index 7d346e917d..480ff60ba2 100644
--- a/actionview/test/actionpack/abstract/helper_test.rb
+++ b/actionview/test/actionpack/abstract/helper_test.rb
@@ -1,17 +1,18 @@
-require 'abstract_unit'
+# frozen_string_literal: true
 
-ActionController::Base.helpers_path = File.expand_path('../../../fixtures/helpers', __FILE__)
+require "abstract_unit"
+
+ActionController::Base.helpers_path = File.expand_path("../../fixtures/helpers", __dir__)
 
 module AbstractController
   module Testing
-
     class ControllerWithHelpers < AbstractController::Base
       include AbstractController::Helpers
       include AbstractController::Rendering
       include ActionView::Rendering
 
       def with_module
-        render :inline => "Module <%= included_method %>"
+        render inline: "Module <%= included_method %>"
       end
     end
 
@@ -31,11 +32,11 @@ module AbstractController
       helper :abc
 
       def with_block
-        render :inline => "Hello <%= helpery_test %>"
+        render inline: "Hello <%= helpery_test %>"
       end
 
       def with_symbol
-        render :inline => "I respond to bare_a: <%= respond_to?(:bare_a) %>"
+        render inline: "I respond to bare_a: <%= respond_to?(:bare_a) %>"
       end
     end
 
@@ -52,7 +53,7 @@ module AbstractController
     class AbstractInvalidHelpers < AbstractHelpers
       include ActionController::Helpers
 
-      path = File.expand_path('../../../fixtures/helpers_missing', __FILE__)
+      path = File.expand_path("../../fixtures/helpers_missing", __dir__)
       $:.unshift(path)
       self.helpers_path = path
     end
@@ -110,7 +111,7 @@ module AbstractController
     class InvalidHelpersTest < ActiveSupport::TestCase
       def test_controller_raise_error_about_real_require_problem
         e = assert_raise(LoadError) { AbstractInvalidHelpers.helper(:invalid_require) }
-        assert_equal "No such file to load -- very_invalid_file_name", e.message
+        assert_equal "No such file to load -- very_invalid_file_name.rb", e.message
       end
 
       def test_controller_raise_error_about_missing_helper
diff --git a/actionview/test/actionpack/abstract/layouts_test.rb b/actionview/test/actionpack/abstract/layouts_test.rb
index 78f6e78c61..1146e6f64b 100644
--- a/actionview/test/actionpack/abstract/layouts_test.rb
+++ b/actionview/test/actionpack/abstract/layouts_test.rb
@@ -1,8 +1,9 @@
-require 'abstract_unit'
+# frozen_string_literal: true
+
+require "abstract_unit"
 
 module AbstractControllerTests
   module Layouts
-
     # Base controller for these tests
     class Base < AbstractController::Base
       include AbstractController::Rendering
@@ -30,7 +31,7 @@ module AbstractControllerTests
       self.view_paths = []
 
       def index
-        render :template => ActionView::Template::Text.new("Hello blank!")
+        render template: ActionView::Template::Text.new("Hello blank!")
       end
     end
 
@@ -38,7 +39,7 @@ module AbstractControllerTests
       layout "hello_locals"
 
       def index
-        render :template => 'some/template', locals: { foo: "less than 3" }
+        render template: "some/template", locals: { foo: "less than 3" }
       end
     end
 
@@ -46,7 +47,7 @@ module AbstractControllerTests
       layout "hello"
 
       def index
-        render :template => ActionView::Template::Text.new("Hello string!")
+        render template: ActionView::Template::Text.new("Hello string!")
       end
 
       def action_has_layout_false
@@ -54,15 +55,15 @@ module AbstractControllerTests
       end
 
       def overwrite_default
-        render :template => ActionView::Template::Text.new("Hello string!"), :layout => :default
+        render template: ActionView::Template::Text.new("Hello string!"), layout: :default
       end
 
       def overwrite_false
-        render :template => ActionView::Template::Text.new("Hello string!"), :layout => false
+        render template: ActionView::Template::Text.new("Hello string!"), layout: false
       end
 
       def overwrite_string
-        render :template => ActionView::Template::Text.new("Hello string!"), :layout => "overwrite"
+        render template: ActionView::Template::Text.new("Hello string!"), layout: "overwrite"
       end
 
       def overwrite_skip
@@ -92,7 +93,7 @@ module AbstractControllerTests
       layout proc { "overwrite" }
 
       def index
-        render :template => ActionView::Template::Text.new("Hello proc!")
+        render template: ActionView::Template::Text.new("Hello proc!")
       end
     end
 
@@ -116,7 +117,7 @@ module AbstractControllerTests
       layout proc { "overwrite" }
 
       def index
-        render :template => ActionView::Template::Text.new("Hello zero arity proc!")
+        render template: ActionView::Template::Text.new("Hello zero arity proc!")
       end
     end
 
@@ -129,7 +130,7 @@ module AbstractControllerTests
       }
 
       def index
-        render :template => ActionView::Template::Text.new("Hello again zero arity proc!")
+        render template: ActionView::Template::Text.new("Hello again zero arity proc!")
       end
     end
 
@@ -137,7 +138,7 @@ module AbstractControllerTests
       layout :hello
 
       def index
-        render :template => ActionView::Template::Text.new("Hello symbol!")
+        render template: ActionView::Template::Text.new("Hello symbol!")
       end
     private
       def hello
@@ -149,7 +150,7 @@ module AbstractControllerTests
       layout :nilz
 
       def index
-        render :template => ActionView::Template::Text.new("Hello nilz!")
+        render template: ActionView::Template::Text.new("Hello nilz!")
       end
 
       def nilz() end
@@ -159,7 +160,7 @@ module AbstractControllerTests
       layout :objekt
 
       def index
-        render :template => ActionView::Template::Text.new("Hello nilz!")
+        render template: ActionView::Template::Text.new("Hello nilz!")
       end
 
       def objekt
@@ -171,7 +172,7 @@ module AbstractControllerTests
       layout :no_method
 
       def index
-        render :template => ActionView::Template::Text.new("Hello boom!")
+        render template: ActionView::Template::Text.new("Hello boom!")
       end
     end
 
@@ -179,7 +180,7 @@ module AbstractControllerTests
       layout "missing"
 
       def index
-        render :template => ActionView::Template::Text.new("Hello missing!")
+        render template: ActionView::Template::Text.new("Hello missing!")
       end
     end
 
@@ -187,7 +188,7 @@ module AbstractControllerTests
       layout false
 
       def index
-        render :template => ActionView::Template::Text.new("Hello false!")
+        render template: ActionView::Template::Text.new("Hello false!")
       end
     end
 
@@ -195,19 +196,19 @@ module AbstractControllerTests
       layout nil
 
       def index
-        render :template => ActionView::Template::Text.new("Hello nil!")
+        render template: ActionView::Template::Text.new("Hello nil!")
       end
     end
 
     class WithOnlyConditional < WithStringImpliedChild
-      layout "overwrite", :only => :show
+      layout "overwrite", only: :show
 
       def index
-        render :template => ActionView::Template::Text.new("Hello index!")
+        render template: ActionView::Template::Text.new("Hello index!")
       end
 
       def show
-        render :template => ActionView::Template::Text.new("Hello show!")
+        render template: ActionView::Template::Text.new("Hello show!")
       end
     end
 
@@ -220,14 +221,14 @@ module AbstractControllerTests
     end
 
     class WithExceptConditional < WithStringImpliedChild
-      layout "overwrite", :except => :show
+      layout "overwrite", except: :show
 
       def index
-        render :template => ActionView::Template::Text.new("Hello index!")
+        render template: ActionView::Template::Text.new("Hello index!")
       end
 
       def show
-        render :template => ActionView::Template::Text.new("Hello show!")
+        render template: ActionView::Template::Text.new("Hello show!")
       end
     end
 
@@ -294,7 +295,7 @@ module AbstractControllerTests
         10.times do |x|
           controller = WithString.new
           controller.define_singleton_method :index do
-            render :template => ActionView::Template::Text.new("Hello string!"), :locals => { :"x#{x}" => :omg }
+            render template: ActionView::Template::Text.new("Hello string!"), locals: { :"x#{x}" => :omg }
           end
           controller.process(:index)
         end
@@ -349,7 +350,7 @@ module AbstractControllerTests
       end
 
       test "when layout is specified as a proc, do not leak any methods into controller's action_methods" do
-        assert_equal Set.new(['index']), WithProc.action_methods
+        assert_equal Set.new(["index"]), WithProc.action_methods
       end
 
       test "when layout is specified as a proc, call it and use the layout returned" do
@@ -422,16 +423,16 @@ module AbstractControllerTests
 
       test "when a grandchild has no layout specified, the child has an implied layout, and the " \
         "parent has specified a layout, use the child controller layout" do
-          controller = WithChildOfImplied.new
-          controller.process(:index)
-          assert_equal "With Implied Hello string!", controller.response_body
+        controller = WithChildOfImplied.new
+        controller.process(:index)
+        assert_equal "With Implied Hello string!", controller.response_body
       end
 
       test "when a grandchild has nil layout specified, the child has an implied layout, and the " \
         "parent has specified a layout, use the grand child controller layout" do
-          controller = WithGrandChildOfImplied.new
-          controller.process(:index)
-          assert_equal "With Grand Child Hello string!", controller.response_body
+        controller = WithGrandChildOfImplied.new
+        controller.process(:index)
+        assert_equal "With Grand Child Hello string!", controller.response_body
       end
 
       test "a child inherits layout from abstract controller" do
@@ -543,7 +544,7 @@ module AbstractControllerTests
       test "layout for anonymous controller" do
         klass = Class.new(WithString) do
           def index
-            render plain: 'index', layout: true
+            render plain: "index", layout: true
           end
         end
 
diff --git a/actionview/test/actionpack/abstract/render_test.rb b/actionview/test/actionpack/abstract/render_test.rb
index e185b76adb..d863548a5c 100644
--- a/actionview/test/actionpack/abstract/render_test.rb
+++ b/actionview/test/actionpack/abstract/render_test.rb
@@ -1,8 +1,9 @@
-require 'abstract_unit'
+# frozen_string_literal: true
+
+require "abstract_unit"
 
 module AbstractController
   module Testing
-
     class ControllerRenderer < AbstractController::Base
       include AbstractController::Rendering
       include ActionView::Rendering
@@ -21,15 +22,15 @@ module AbstractController
       )]
 
       def template
-        render :template => "template"
+        render template: "template"
       end
 
       def file
-        render :file => "some/file"
+        render file: "some/file"
       end
 
       def inline
-        render :inline => "With <%= :Inline %>"
+        render inline: "With <%= :Inline %>"
       end
 
       def text
@@ -54,7 +55,6 @@ module AbstractController
     end
 
     class TestRenderer < ActiveSupport::TestCase
-
       def setup
         @controller = ControllerRenderer.new
       end
diff --git a/actionview/test/actionpack/controller/capture_test.rb b/actionview/test/actionpack/controller/capture_test.rb
index 933456ce9d..09309e5b6d 100644
--- a/actionview/test/actionpack/controller/capture_test.rb
+++ b/actionview/test/actionpack/controller/capture_test.rb
@@ -1,30 +1,32 @@
-require 'abstract_unit'
-require 'active_support/logger'
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "active_support/logger"
 
 class CaptureController < ActionController::Base
-  self.view_paths = [ File.dirname(__FILE__) + '/../../fixtures/actionpack' ]
+  self.view_paths = [ File.expand_path("../../fixtures/actionpack", __dir__) ]
 
   def self.controller_name; "test"; end
   def self.controller_path; "test"; end
 
   def content_for
     @title = nil
-    render :layout => "talk_from_action"
+    render layout: "talk_from_action"
   end
 
   def content_for_with_parameter
     @title = nil
-    render :layout => "talk_from_action"
+    render layout: "talk_from_action"
   end
 
   def content_for_concatenated
     @title = nil
-    render :layout => "talk_from_action"
+    render layout: "talk_from_action"
   end
 
   def non_erb_block_content_for
     @title = nil
-    render :layout => "talk_from_action"
+    render layout: "talk_from_action"
   end
 
   def proper_block_detection
diff --git a/actionview/test/actionpack/controller/layout_test.rb b/actionview/test/actionpack/controller/layout_test.rb
index 64bc4c41d6..ff66ff2a1a 100644
--- a/actionview/test/actionpack/controller/layout_test.rb
+++ b/actionview/test/actionpack/controller/layout_test.rb
@@ -1,15 +1,17 @@
-require 'abstract_unit'
-require 'active_support/core_ext/array/extract_options'
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "active_support/core_ext/array/extract_options"
 
 # The view_paths array must be set on Base and not LayoutTest so that LayoutTest's inherited
 # method has access to the view_paths array when looking for a layout to automatically assign.
 old_load_paths = ActionController::Base.view_paths
 
-ActionController::Base.view_paths = [ File.dirname(__FILE__) + '/../../fixtures/actionpack/layout_tests/' ]
+ActionController::Base.view_paths = [ File.expand_path("../../fixtures/actionpack/layout_tests", __dir__) ]
 
 class LayoutTest < ActionController::Base
-  def self.controller_path; 'views' end
-  def self._implied_layout_name; to_s.underscore.gsub(/_controller$/, '') ; end
+  def self.controller_path; "views" end
+  def self._implied_layout_name; to_s.underscore.gsub(/_controller$/, "") ; end
   self.view_paths = ActionController::Base.view_paths.dup
 end
 
@@ -54,13 +56,13 @@ class LayoutAutoDiscoveryTest < ActionController::TestCase
   def test_application_layout_is_default_when_no_controller_match
     @controller = ProductController.new
     get :hello
-    assert_equal 'layout_test.erb hello.erb', @response.body
+    assert_equal "layout_test.erb hello.erb", @response.body
   end
 
   def test_controller_name_layout_name_match
     @controller = ItemController.new
     get :hello
-    assert_equal 'item.erb hello.erb', @response.body
+    assert_equal "item.erb hello.erb", @response.body
   end
 
   def test_third_party_template_library_auto_discovers_layout
@@ -68,20 +70,20 @@ class LayoutAutoDiscoveryTest < ActionController::TestCase
       @controller = ThirdPartyTemplateLibraryController.new
       get :hello
       assert_response :success
-      assert_equal 'layouts/third_party_template_library.mab', @response.body
+      assert_equal "layouts/third_party_template_library.mab", @response.body
     end
   end
 
   def test_namespaced_controllers_auto_detect_layouts1
     @controller = ControllerNameSpace::NestedController.new
     get :hello
-    assert_equal 'controller_name_space/nested.erb hello.erb', @response.body
+    assert_equal "controller_name_space/nested.erb hello.erb", @response.body
   end
 
   def test_namespaced_controllers_auto_detect_layouts2
     @controller = MultipleExtensions.new
     get :hello
-    assert_equal 'multiple_extensions.html.erb hello.erb', @response.body.strip
+    assert_equal "multiple_extensions.html.erb hello.erb", @response.body.strip
   end
 end
 
@@ -91,16 +93,16 @@ end
 class StreamingLayoutController < LayoutTest
   def render(*args)
     options = args.extract_options!
-    super(*args, options.merge(:stream => true))
+    super(*args, options.merge(stream: true))
   end
 end
 
 class AbsolutePathLayoutController < LayoutTest
-  layout File.expand_path(File.expand_path(__FILE__) + '/../../../fixtures/actionpack/layout_tests/layouts/layout_test')
+  layout File.expand_path("../../fixtures/actionpack/layout_tests/layouts/layout_test", __dir__)
 end
 
 class HasOwnLayoutController < LayoutTest
-  layout 'item'
+  layout "item"
 end
 
 class HasNilLayoutSymbol < LayoutTest
@@ -117,28 +119,28 @@ end
 
 class PrependsViewPathController < LayoutTest
   def hello
-    prepend_view_path File.dirname(__FILE__) + '/../../fixtures/actionpack/layout_tests/alt/'
-    render :layout => 'alt'
+    prepend_view_path File.expand_path("../../fixtures/actionpack/layout_tests/alt", __dir__)
+    render layout: "alt"
   end
 end
 
 class OnlyLayoutController < LayoutTest
-  layout 'item', :only => "hello"
+  layout "item", only: "hello"
 end
 
 class ExceptLayoutController < LayoutTest
-  layout 'item', :except => "goodbye"
+  layout "item", except: "goodbye"
 end
 
 class SetsLayoutInRenderController < LayoutTest
   def hello
-    render :layout => 'third_party_template_library'
+    render layout: "third_party_template_library"
   end
 end
 
 class RendersNoLayoutController < LayoutTest
   def hello
-    render :layout => false
+    render layout: false
   end
 end
 
@@ -149,75 +151,75 @@ class LayoutSetInResponseTest < ActionController::TestCase
   def test_layout_set_when_using_default_layout
     @controller = DefaultLayoutController.new
     get :hello
-    assert_includes @response.body, 'layout_test.erb'
+    assert_includes @response.body, "layout_test.erb"
   end
 
   def test_layout_set_when_using_streaming_layout
     @controller = StreamingLayoutController.new
     get :hello
-    assert_includes @response.body, 'layout_test.erb'
+    assert_includes @response.body, "layout_test.erb"
   end
 
   def test_layout_set_when_set_in_controller
     @controller = HasOwnLayoutController.new
     get :hello
-    assert_includes @response.body, 'item.erb'
+    assert_includes @response.body, "item.erb"
   end
 
   def test_layout_symbol_set_in_controller_returning_nil_falls_back_to_default
     @controller = HasNilLayoutSymbol.new
     get :hello
-    assert_includes @response.body, 'layout_test.erb'
+    assert_includes @response.body, "layout_test.erb"
   end
 
   def test_layout_proc_set_in_controller_returning_nil_falls_back_to_default
     @controller = HasNilLayoutProc.new
     get :hello
-    assert_includes @response.body, 'layout_test.erb'
+    assert_includes @response.body, "layout_test.erb"
   end
 
   def test_layout_only_exception_when_included
     @controller = OnlyLayoutController.new
     get :hello
-    assert_includes @response.body, 'item.erb'
+    assert_includes @response.body, "item.erb"
   end
 
   def test_layout_only_exception_when_excepted
     @controller = OnlyLayoutController.new
     get :goodbye
-    assert_not_includes @response.body, 'item.erb'
+    assert_not_includes @response.body, "item.erb"
   end
 
   def test_layout_except_exception_when_included
     @controller = ExceptLayoutController.new
     get :hello
-    assert_includes @response.body, 'item.erb'
+    assert_includes @response.body, "item.erb"
   end
 
   def test_layout_except_exception_when_excepted
     @controller = ExceptLayoutController.new
     get :goodbye
-    assert_not_includes @response.body, 'item.erb'
+    assert_not_includes @response.body, "item.erb"
   end
 
   def test_layout_set_when_using_render
     with_template_handler :mab, lambda { |template| template.source.inspect } do
       @controller = SetsLayoutInRenderController.new
       get :hello
-      assert_includes @response.body, 'layouts/third_party_template_library.mab'
+      assert_includes @response.body, "layouts/third_party_template_library.mab"
     end
   end
 
   def test_layout_is_not_set_when_none_rendered
     @controller = RendersNoLayoutController.new
     get :hello
-    assert_equal 'hello.erb', @response.body
+    assert_equal "hello.erb", @response.body
   end
 
   def test_layout_is_picked_from_the_controller_instances_view_path
     @controller = PrependsViewPathController.new
     get :hello
-    assert_includes @response.body, 'alt.erb'
+    assert_includes @response.body, "alt.erb"
   end
 
   def test_absolute_pathed_layout
@@ -240,7 +242,7 @@ end
 
 class LayoutStatusIsRendered < LayoutTest
   def hello
-    render :status => 401
+    render status: 401
   end
 end
 
@@ -252,7 +254,7 @@ class LayoutStatusIsRenderedTest < ActionController::TestCase
   end
 end
 
-unless RbConfig::CONFIG['host_os'] =~ /mswin|mingw/
+unless Gem.win_platform?
   class LayoutSymlinkedTest < LayoutTest
     layout "symlinked/symlinked_layout"
   end
@@ -262,7 +264,7 @@ unless RbConfig::CONFIG['host_os'] =~ /mswin|mingw/
       @controller = LayoutSymlinkedTest.new
       get :hello
       assert_response 200
-      assert_includes @response.body, 'This is my layout'
+      assert_includes @response.body, "This is my layout"
     end
   end
 end
diff --git a/actionview/test/actionpack/controller/render_test.rb b/actionview/test/actionpack/controller/render_test.rb
index 7b69ffc628..8a9d7982d3 100644
--- a/actionview/test/actionpack/controller/render_test.rb
+++ b/actionview/test/actionpack/controller/render_test.rb
@@ -1,45 +1,16 @@
-require 'abstract_unit'
-require 'active_model'
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "active_model"
+require "controller/fake_models"
 
 class ApplicationController < ActionController::Base
   self.view_paths = File.join(FIXTURE_LOAD_PATH, "actionpack")
 end
 
-class Customer < Struct.new(:name, :id)
-  extend ActiveModel::Naming
-  include ActiveModel::Conversion
-
-  undef_method :to_json
-
-  def to_xml(options={})
-    if options[:builder]
-      options[:builder].name name
-    else
-      "<name>#{name}</name>"
-    end
-  end
-
-  def to_js(options={})
-    "name: #{name.inspect}"
-  end
-  alias :to_text :to_js
-
-  def errors
-    []
-  end
-
-  def persisted?
-    id.present?
-  end
-
-  def cache_key
-    name.to_s
-  end
-end
-
 module Quiz
-  #Models
-  class Question < Struct.new(:name, :id)
+  # Models
+  Question = Struct.new(:name, :id) do
     extend ActiveModel::Naming
     include ActiveModel::Conversion
 
@@ -51,20 +22,17 @@ module Quiz
   # Controller
   class QuestionsController < ApplicationController
     def new
-      render :partial => Quiz::Question.new("Namespaced Partial")
+      render partial: Quiz::Question.new("Namespaced Partial")
     end
   end
 end
 
-class BadCustomer < Customer; end
-class GoodCustomer < Customer; end
-
 module Fun
   class GamesController < ApplicationController
     def hello_world; end
 
     def nested_partial_with_form_builder
-      render :partial => ActionView::Helpers::FormBuilder.new(:post, nil, view_context, {})
+      render partial: ActionView::Helpers::FormBuilder.new(:post, nil, view_context, {})
     end
   end
 end
@@ -90,7 +58,7 @@ class TestController < ApplicationController
   end
 
   def hello_world_file
-    render :file => File.expand_path("../../../fixtures/actionpack/hello", __FILE__), :formats => [:html]
+    render file: File.expand_path("../../fixtures/actionpack/hello", __dir__), formats: [:html]
   end
 
   # :ported:
@@ -110,12 +78,12 @@ class TestController < ApplicationController
 
   # :ported:
   def render_template_in_top_directory
-    render :template => 'shared'
+    render template: "shared"
   end
 
   # :deprecated:
   def render_template_in_top_directory_with_slash
-    render '/shared'
+    render "/shared"
   end
 
   # :ported:
@@ -126,11 +94,11 @@ class TestController < ApplicationController
 
   # :ported:
   def render_action_hello_world
-    render :action => "hello_world"
+    render action: "hello_world"
   end
 
   def render_action_upcased_hello_world
-    render :action => "Hello_world"
+    render action: "Hello_world"
   end
 
   def render_action_hello_world_as_string
@@ -138,7 +106,7 @@ class TestController < ApplicationController
   end
 
   def render_action_hello_world_with_symbol
-    render :action => :hello_world
+    render action: :hello_world
   end
 
   # :ported:
@@ -149,70 +117,70 @@ class TestController < ApplicationController
   # :ported:
   def render_text_hello_world_with_layout
     @variable_for_layout = ", I am here!"
-    render plain: "hello world", :layout => true
+    render plain: "hello world", layout: true
   end
 
   def hello_world_with_layout_false
-    render :layout => false
+    render layout: false
   end
 
   # :ported:
   def render_file_with_instance_variables
-    @secret = 'in the sauce'
-    path = File.join(File.dirname(__FILE__), '../../fixtures/test/render_file_with_ivar')
-    render :file => path
+    @secret = "in the sauce"
+    path = File.expand_path("../../fixtures/test/render_file_with_ivar", __dir__)
+    render file: path
   end
 
   # :ported:
   def render_file_not_using_full_path
-    @secret = 'in the sauce'
-    render :file => 'test/render_file_with_ivar'
+    @secret = "in the sauce"
+    render file: "test/render_file_with_ivar"
   end
 
   def render_file_not_using_full_path_with_dot_in_path
-    @secret = 'in the sauce'
-    render :file => 'test/dot.directory/render_file_with_ivar'
+    @secret = "in the sauce"
+    render file: "test/dot.directory/render_file_with_ivar"
   end
 
   def render_file_using_pathname
-    @secret = 'in the sauce'
-    render :file => Pathname.new(File.dirname(__FILE__)).join('..', '..', 'fixtures', 'test', 'dot.directory', 'render_file_with_ivar')
+    @secret = "in the sauce"
+    render file: Pathname.new(__dir__).join("..", "..", "fixtures", "test", "dot.directory", "render_file_with_ivar")
   end
 
   def render_file_from_template
-    @secret = 'in the sauce'
-    @path = File.expand_path(File.join(File.dirname(__FILE__), '../../fixtures/test/render_file_with_ivar'))
+    @secret = "in the sauce"
+    @path = File.expand_path("../../fixtures/test/render_file_with_ivar", __dir__)
   end
 
   def render_file_with_locals
-    path = File.join(File.dirname(__FILE__), '../../fixtures/test/render_file_with_locals')
-    render :file => path, :locals => {:secret => 'in the sauce'}
+    path = File.expand_path("../../fixtures/test/render_file_with_locals", __dir__)
+    render file: path, locals: { secret: "in the sauce" }
   end
 
   def render_file_as_string_with_locals
-    path = File.expand_path(File.join(File.dirname(__FILE__), '../../fixtures/test/render_file_with_locals'))
-    render file: path, :locals => {:secret => 'in the sauce'}
+    path = File.expand_path("../../fixtures/test/render_file_with_locals", __dir__)
+    render file: path, locals: { secret: "in the sauce" }
   end
 
   def accessing_request_in_template
-    render :inline =>  "Hello: <%= request.host %>"
+    render inline: "Hello: <%= request.host %>"
   end
 
   def accessing_logger_in_template
-    render :inline =>  "<%= logger.class %>"
+    render inline: "<%= logger.class %>"
   end
 
   def accessing_action_name_in_template
-    render :inline =>  "<%= action_name %>"
+    render inline: "<%= action_name %>"
   end
 
   def accessing_controller_name_in_template
-    render :inline =>  "<%= controller_name %>"
+    render inline: "<%= controller_name %>"
   end
 
   # :ported:
   def render_custom_code
-    render plain: "hello world", :status => 404
+    render plain: "hello world", status: 404
   end
 
   # :ported:
@@ -240,7 +208,7 @@ class TestController < ApplicationController
   #   setting content type
   def render_xml_hello
     @name = "David"
-    render :template => "test/hello"
+    render template: "test/hello"
   end
 
   def render_xml_hello_as_string_template
@@ -249,7 +217,7 @@ class TestController < ApplicationController
   end
 
   def render_line_offset
-    render :inline => '<% raise %>', :locals => {:foo => 'bar'}
+    render inline: "<% raise %>", locals: { foo: "bar" }
   end
 
   def heading
@@ -262,49 +230,49 @@ class TestController < ApplicationController
 
   # :ported:
   def blank_response
-    render plain: ' '
+    render plain: " "
   end
 
   # :ported:
   def layout_test
-    render :action => "hello_world"
+    render action: "hello_world"
   end
 
   # :ported:
   def builder_layout_test
     @name = nil
-    render :action => "hello", :layout => "layouts/builder"
+    render action: "hello", layout: "layouts/builder"
   end
 
   # :move: test this in Action View
   def builder_partial_test
-    render :action => "hello_world_container"
+    render action: "hello_world_container"
   end
 
   # :ported:
   def partials_list
-    @test_unchanged = 'hello'
+    @test_unchanged = "hello"
     @customers = [ Customer.new("david"), Customer.new("mary") ]
-    render :action => "list"
+    render action: "list"
   end
 
   def partial_only
-    render :partial => true
+    render partial: true
   end
 
   def hello_in_a_string
     @customers = [ Customer.new("david"), Customer.new("mary") ]
-    render plain: "How's there? " + render_to_string(:template => "test/list")
+    render plain: "How's there? " + render_to_string(template: "test/list")
   end
 
   def accessing_params_in_template
-    render :inline => "Hello: <%= params[:name] %>"
+    render inline: "Hello: <%= params[:name] %>"
   end
 
   def accessing_local_assigns_in_inline_template
     name = params[:local_name]
-    render :inline => "<%= 'Goodbye, ' + local_name %>",
-           :locals => { :local_name => name }
+    render inline: "<%= 'Goodbye, ' + local_name %>",
+           locals: { local_name: name }
   end
 
   def render_implicit_html_template_from_xhr_request
@@ -320,7 +288,7 @@ class TestController < ApplicationController
   end
 
   def render_to_string_test
-    @foo = render_to_string :inline => "this is a test"
+    @foo = render_to_string inline: "this is a test"
   end
 
   def default_render
@@ -333,27 +301,27 @@ class TestController < ApplicationController
   end
 
   def render_action_hello_world_as_symbol
-    render :action => :hello_world
+    render action: :hello_world
   end
 
   def layout_test_with_different_layout
-    render :action => "hello_world", :layout => "standard"
+    render action: "hello_world", layout: "standard"
   end
 
   def layout_test_with_different_layout_and_string_action
-    render "hello_world", :layout => "standard"
+    render "hello_world", layout: "standard"
   end
 
   def layout_test_with_different_layout_and_symbol_action
-    render :hello_world, :layout => "standard"
+    render :hello_world, layout: "standard"
   end
 
   def rendering_without_layout
-    render :action => "hello_world", :layout => false
+    render action: "hello_world", layout: false
   end
 
   def layout_overriding_layout
-    render :action => "hello_world", :layout => "standard"
+    render action: "hello_world", layout: "standard"
   end
 
   def rendering_nothing_on_layout
@@ -364,38 +332,38 @@ class TestController < ApplicationController
     @before = "i'm before the render"
     render_to_string plain: "foo"
     @after = "i'm after the render"
-    render :template => "test/hello_world"
+    render template: "test/hello_world"
   end
 
   def render_to_string_with_exception
-    render_to_string :file => "exception that will not be caught - this will certainly not work"
+    render_to_string file: "exception that will not be caught - this will certainly not work"
   end
 
   def render_to_string_with_caught_exception
     @before = "i'm before the render"
     begin
-      render_to_string :file => "exception that will be caught- hope my future instance vars still work!"
+      render_to_string file: "exception that will be caught- hope my future instance vars still work!"
     rescue
     end
     @after = "i'm after the render"
-    render :template => "test/hello_world"
+    render template: "test/hello_world"
   end
 
   def accessing_params_in_template_with_layout
-    render :layout => true, :inline =>  "Hello: <%= params[:name] %>"
+    render layout: true, inline: "Hello: <%= params[:name] %>"
   end
 
   # :ported:
   def render_with_explicit_template
-    render :template => "test/hello_world"
+    render template: "test/hello_world"
   end
 
   def render_with_explicit_unescaped_template
-    render :template => "test/h*llo_world"
+    render template: "test/h*llo_world"
   end
 
   def render_with_explicit_escaped_template
-    render :template => "test/hello,world"
+    render template: "test/hello,world"
   end
 
   def render_with_explicit_string_template
@@ -404,7 +372,7 @@ class TestController < ApplicationController
 
   # :ported:
   def render_with_explicit_template_with_locals
-    render :template => "test/render_file_with_locals", :locals => { :secret => 'area51' }
+    render template: "test/render_file_with_locals", locals: { secret: "area51" }
   end
 
   # :ported:
@@ -414,13 +382,13 @@ class TestController < ApplicationController
   end
 
   def double_redirect
-    redirect_to :action => "double_render"
-    redirect_to :action => "double_render"
+    redirect_to action: "double_render"
+    redirect_to action: "double_render"
   end
 
   def render_and_redirect
     render plain: "hello"
-    redirect_to :action => "double_render"
+    redirect_to action: "double_render"
   end
 
   def render_to_string_and_render
@@ -429,22 +397,22 @@ class TestController < ApplicationController
   end
 
   def render_to_string_with_inline_and_render
-    render_to_string :inline => "<%= 'dlrow olleh'.reverse %>"
-    render :template => "test/hello_world"
+    render_to_string inline: "<%= 'dlrow olleh'.reverse %>"
+    render template: "test/hello_world"
   end
 
   def rendering_with_conflicting_local_vars
     @name = "David"
-    render :action => "potential_conflicts"
+    render action: "potential_conflicts"
   end
 
   def hello_world_from_rxml_using_action
-    render :action => "hello_world_from_rxml", :handlers => [:builder]
+    render action: "hello_world_from_rxml", handlers: [:builder]
   end
 
   # :deprecated:
   def hello_world_from_rxml_using_template
-    render :template => "test/hello_world_from_rxml", :handlers => [:builder]
+    render template: "test/hello_world_from_rxml", handlers: [:builder]
   end
 
   def action_talk_to_layout
@@ -458,11 +426,11 @@ class TestController < ApplicationController
   end
 
   def render_with_assigns_option
-    render inline: '<%= @hello %>', assigns: { hello: "world" }
+    render inline: "<%= @hello %>", assigns: { hello: "world" }
   end
 
   def yield_content_for
-    render :action => "content_for", :layout => "yield"
+    render action: "content_for", layout: "yield"
   end
 
   def render_content_type_from_body
@@ -471,117 +439,117 @@ class TestController < ApplicationController
   end
 
   def render_using_layout_around_block
-    render :action => "using_layout_around_block"
+    render action: "using_layout_around_block"
   end
 
   def render_using_layout_around_block_in_main_layout_and_within_content_for_layout
-    render :action => "using_layout_around_block", :layout => "layouts/block_with_layout"
+    render action: "using_layout_around_block", layout: "layouts/block_with_layout"
   end
 
   def partial_formats_html
-    render :partial => 'partial', :formats => [:html]
+    render partial: "partial", formats: [:html]
   end
 
   def partial
-    render :partial => 'partial'
+    render partial: "partial"
   end
 
   def partial_html_erb
-    render :partial => 'partial_html_erb'
+    render partial: "partial_html_erb"
   end
 
   def render_to_string_with_partial
-    @partial_only = render_to_string :partial => "partial_only"
-    @partial_with_locals = render_to_string :partial => "customer", :locals => { :customer => Customer.new("david") }
-    render :template => "test/hello_world"
+    @partial_only = render_to_string partial: "partial_only"
+    @partial_with_locals = render_to_string partial: "customer", locals: { customer: Customer.new("david") }
+    render template: "test/hello_world"
   end
 
   def render_to_string_with_template_and_html_partial
-    @text = render_to_string :template => "test/with_partial", :formats => [:text]
-    @html = render_to_string :template => "test/with_partial", :formats => [:html]
-    render :template => "test/with_html_partial"
+    @text = render_to_string template: "test/with_partial", formats: [:text]
+    @html = render_to_string template: "test/with_partial", formats: [:html]
+    render template: "test/with_html_partial"
   end
 
   def render_to_string_and_render_with_different_formats
-    @html = render_to_string :template => "test/with_partial", :formats => [:html]
-    render :template => "test/with_partial", :formats => [:text]
+    @html = render_to_string template: "test/with_partial", formats: [:html]
+    render template: "test/with_partial", formats: [:text]
   end
 
   def render_template_within_a_template_with_other_format
-    render  :template => "test/with_xml_template",
-            :formats  => [:html],
-            :layout   => "with_html_partial"
+    render  template: "test/with_xml_template",
+            formats: [:html],
+            layout: "with_html_partial"
   end
 
   def partial_with_counter
-    render :partial => "counter", :locals => { :counter_counter => 5 }
+    render partial: "counter", locals: { counter_counter: 5 }
   end
 
   def partial_with_locals
-    render :partial => "customer", :locals => { :customer => Customer.new("david") }
+    render partial: "customer", locals: { customer: Customer.new("david") }
   end
 
   def partial_with_form_builder
-    render :partial => ActionView::Helpers::FormBuilder.new(:post, nil, view_context, {})
+    render partial: ActionView::Helpers::FormBuilder.new(:post, nil, view_context, {})
   end
 
   def partial_with_form_builder_subclass
-    render :partial => LabellingFormBuilder.new(:post, nil, view_context, {})
+    render partial: LabellingFormBuilder.new(:post, nil, view_context, {})
   end
 
   def partial_collection
-    render :partial => "customer", :collection => [ Customer.new("david"), Customer.new("mary") ]
+    render partial: "customer", collection: [ Customer.new("david"), Customer.new("mary") ]
   end
 
   def partial_collection_with_as
-    render :partial => "customer_with_var", :collection => [ Customer.new("david"), Customer.new("mary") ], :as => :customer
+    render partial: "customer_with_var", collection: [ Customer.new("david"), Customer.new("mary") ], as: :customer
   end
 
   def partial_collection_with_iteration
-    render partial: "customer_iteration", collection: [ Customer.new("david"), Customer.new("mary"), Customer.new('christine') ]
+    render partial: "customer_iteration", collection: [ Customer.new("david"), Customer.new("mary"), Customer.new("christine") ]
   end
 
   def partial_collection_with_as_and_iteration
-    render partial: "customer_iteration_with_as", collection: [ Customer.new("david"), Customer.new("mary"), Customer.new('christine') ], as: :client
+    render partial: "customer_iteration_with_as", collection: [ Customer.new("david"), Customer.new("mary"), Customer.new("christine") ], as: :client
   end
 
   def partial_collection_with_counter
-    render :partial => "customer_counter", :collection => [ Customer.new("david"), Customer.new("mary") ]
+    render partial: "customer_counter", collection: [ Customer.new("david"), Customer.new("mary") ]
   end
 
   def partial_collection_with_as_and_counter
-    render :partial => "customer_counter_with_as", :collection => [ Customer.new("david"), Customer.new("mary") ], :as => :client
+    render partial: "customer_counter_with_as", collection: [ Customer.new("david"), Customer.new("mary") ], as: :client
   end
 
   def partial_collection_with_locals
-    render :partial => "customer_greeting", :collection => [ Customer.new("david"), Customer.new("mary") ], :locals => { :greeting => "Bonjour" }
+    render partial: "customer_greeting", collection: [ Customer.new("david"), Customer.new("mary") ], locals: { greeting: "Bonjour" }
   end
 
   def partial_collection_with_spacer
-    render :partial => "customer", :spacer_template => "partial_only", :collection => [ Customer.new("david"), Customer.new("mary") ]
+    render partial: "customer", spacer_template: "partial_only", collection: [ Customer.new("david"), Customer.new("mary") ]
   end
 
   def partial_collection_with_spacer_which_uses_render
-    render :partial => "customer", :spacer_template => "partial_with_partial", :collection => [ Customer.new("david"), Customer.new("mary") ]
+    render partial: "customer", spacer_template: "partial_with_partial", collection: [ Customer.new("david"), Customer.new("mary") ]
   end
 
   def partial_collection_shorthand_with_locals
-    render :partial => [ Customer.new("david"), Customer.new("mary") ], :locals => { :greeting => "Bonjour" }
+    render partial: [ Customer.new("david"), Customer.new("mary") ], locals: { greeting: "Bonjour" }
   end
 
   def partial_collection_shorthand_with_different_types_of_records
-    render :partial => [
+    render partial: [
         BadCustomer.new("mark"),
         GoodCustomer.new("craig"),
         BadCustomer.new("john"),
         GoodCustomer.new("zach"),
         GoodCustomer.new("brandon"),
         BadCustomer.new("dan") ],
-      :locals => { :greeting => "Bonjour" }
+      locals: { greeting: "Bonjour" }
   end
 
   def empty_partial_collection
-    render :partial => "customer", :collection => []
+    render partial: "customer", collection: []
   end
 
   def partial_collection_shorthand_with_different_types_of_records_with_counter
@@ -589,15 +557,15 @@ class TestController < ApplicationController
   end
 
   def missing_partial
-    render :partial => 'thisFileIsntHere'
+    render partial: "thisFileIsntHere"
   end
 
   def partial_with_hash_object
-    render :partial => "hash_object", :object => {:first_name => "Sam"}
+    render partial: "hash_object", object: { first_name: "Sam" }
   end
 
   def partial_with_nested_object
-    render :partial => "quiz/questions/question", :object => Quiz::Question.new("first")
+    render partial: "quiz/questions/question", object: Quiz::Question.new("first")
   end
 
   def partial_with_nested_object_shorthand
@@ -605,24 +573,24 @@ class TestController < ApplicationController
   end
 
   def partial_hash_collection
-    render :partial => "hash_object", :collection => [ {:first_name => "Pratik"}, {:first_name => "Amy"} ]
+    render partial: "hash_object", collection: [ { first_name: "Pratik" }, { first_name: "Amy" } ]
   end
 
   def partial_hash_collection_with_locals
-    render :partial => "hash_greeting", :collection => [ {:first_name => "Pratik"}, {:first_name => "Amy"} ], :locals => { :greeting => "Hola" }
+    render partial: "hash_greeting", collection: [ { first_name: "Pratik" }, { first_name: "Amy" } ], locals: { greeting: "Hola" }
   end
 
   def partial_with_implicit_local_assignment
     @customer = Customer.new("Marcel")
-    render :partial => "customer"
+    render partial: "customer"
   end
 
   def render_call_to_partial_with_layout
-    render :action => "calling_partial_with_layout"
+    render action: "calling_partial_with_layout"
   end
 
   def render_call_to_partial_with_layout_in_main_layout_and_within_content_for_layout
-    render :action => "calling_partial_with_layout", :layout => "layouts/partial_with_layout"
+    render action: "calling_partial_with_layout", layout: "layouts/partial_with_layout"
   end
 
   before_action only: :render_with_filters do
@@ -631,7 +599,7 @@ class TestController < ApplicationController
 
   # Ensure that the before filter is executed *before* self.formats is set.
   def render_with_filters
-    render :action => :formatted_xml_erb
+    render action: :formatted_xml_erb
   end
 
   private
@@ -642,7 +610,7 @@ class TestController < ApplicationController
 
     def determine_layout
       case action_name
-        when "hello_world", "layout_test", "rendering_without_layout",
+      when "hello_world", "layout_test", "rendering_without_layout",
              "rendering_nothing_on_layout", "render_text_hello_world",
              "render_text_hello_world_with_layout",
              "hello_world_with_layout_false",
@@ -652,11 +620,11 @@ class TestController < ApplicationController
              "render_with_explicit_string_template",
              "update_page", "update_page_with_instance_variables"
 
-          "layouts/standard"
-        when "action_talk_to_layout", "layout_overriding_layout"
-          "layouts/talk_from_action"
-        when "render_implicit_html_template_from_xhr_request"
-          (request.xhr? ? 'layouts/xhr' : 'layouts/standard')
+        "layouts/standard"
+      when "action_talk_to_layout", "layout_overriding_layout"
+        "layouts/talk_from_action"
+      when "render_implicit_html_template_from_xhr_request"
+        (request.xhr? ? "layouts/xhr" : "layouts/standard")
       end
     end
 end
@@ -771,7 +739,7 @@ class RenderTest < ActionController::TestCase
   # :ported:
   def test_do_with_render_action_and_layout_false
     get :hello_world_with_layout_false
-    assert_equal 'Hello world!', @response.body
+    assert_equal "Hello world!", @response.body
   end
 
   # :ported:
@@ -826,27 +794,27 @@ class RenderTest < ActionController::TestCase
     get :render_custom_code
     assert_response 404
     assert_response :missing
-    assert_equal 'hello world', @response.body
+    assert_equal "hello world", @response.body
   end
 
   # :ported:
   def test_render_text_with_nil
     get :render_text_with_nil
     assert_response 200
-    assert_equal '', @response.body
+    assert_equal "", @response.body
   end
 
   # :ported:
   def test_render_text_with_false
     get :render_text_with_false
-    assert_equal 'false', @response.body
+    assert_equal "false", @response.body
   end
 
   # :ported:
   def test_render_nothing_with_appendix
     get :render_nothing_with_appendix
     assert_response 200
-    assert_equal 'appended', @response.body
+    assert_equal "appended", @response.body
   end
 
   def test_render_text_with_resource
@@ -941,7 +909,7 @@ class RenderTest < ActionController::TestCase
 
   def test_render_to_string_inline
     get :render_to_string_with_inline_and_render
-    assert_equal 'Hello world!', @response.body
+    assert_equal "Hello world!", @response.body
   end
 
   # :ported:
@@ -974,24 +942,24 @@ class RenderTest < ActionController::TestCase
 
   def test_should_render_formatted_template
     get :formatted_html_erb
-    assert_equal 'formatted html erb', @response.body
+    assert_equal "formatted html erb", @response.body
   end
 
   def test_should_render_formatted_html_erb_template
     get :formatted_xml_erb
-    assert_equal '<test>passed formatted html erb</test>', @response.body
+    assert_equal "<test>passed formatted html erb</test>", @response.body
   end
 
   def test_should_render_formatted_html_erb_template_with_bad_accepts_header
     @request.env["HTTP_ACCEPT"] = "; a=dsf"
     get :formatted_xml_erb
-    assert_equal '<test>passed formatted html erb</test>', @response.body
+    assert_equal "<test>passed formatted html erb</test>", @response.body
   end
 
   def test_should_render_formatted_html_erb_template_with_faulty_accepts_header
     @request.accept = "image/gif, image/x-xbitmap, image/jpeg, image/pjpeg, application/x-shockwave-flash, */*"
     get :formatted_xml_erb
-    assert_equal '<test>passed formatted html erb</test>', @response.body
+    assert_equal "<test>passed formatted html erb</test>", @response.body
   end
 
   def test_layout_test_with_different_layout
@@ -1021,7 +989,7 @@ class RenderTest < ActionController::TestCase
 
   def test_rendering_nothing_on_layout
     get :rendering_nothing_on_layout
-    assert_equal '', @response.body
+    assert_equal "", @response.body
   end
 
   def test_render_to_string_doesnt_break_assigns
@@ -1103,7 +1071,7 @@ class RenderTest < ActionController::TestCase
 
   def test_render_text_with_assigns_option
     get :render_with_assigns_option
-    assert_equal 'world', response.body
+    assert_equal "world", response.body
   end
 
   # :ported:
diff --git a/actionview/test/actionpack/controller/view_paths_test.rb b/actionview/test/actionpack/controller/view_paths_test.rb
index e99659c802..45c662f0ce 100644
--- a/actionview/test/actionpack/controller/view_paths_test.rb
+++ b/actionview/test/actionpack/controller/view_paths_test.rb
@@ -1,4 +1,6 @@
-require 'abstract_unit'
+# frozen_string_literal: true
+
+require "abstract_unit"
 
 class ViewLoadPathsTest < ActionController::TestCase
   class TestController < ActionController::Base
@@ -7,7 +9,7 @@ class ViewLoadPathsTest < ActionController::TestCase
     before_action :add_view_path, only: :hello_world_at_request_time
 
     def hello_world() end
-    def hello_world_at_request_time() render(:action => 'hello_world') end
+    def hello_world_at_request_time() render(action: "hello_world") end
 
     private
       def add_view_path
@@ -17,15 +19,15 @@ class ViewLoadPathsTest < ActionController::TestCase
 
   module Test
     class SubController < ActionController::Base
-      layout 'test/sub'
-      def hello_world; render(:template => 'test/hello_world'); end
+      layout "test/sub"
+      def hello_world; render(template: "test/hello_world"); end
     end
   end
 
   def setup
-    @request  = ActionController::TestRequest.create
-    @response = ActionDispatch::TestResponse.new
     @controller = TestController.new
+    @request  = ActionController::TestRequest.create(@controller.class)
+    @response = ActionDispatch::TestResponse.new
     @paths = TestController.view_paths
   end
 
@@ -34,7 +36,7 @@ class ViewLoadPathsTest < ActionController::TestCase
   end
 
   def expand(array)
-    array.map {|x| File.expand_path(x.to_s)}
+    array.map { |x| File.expand_path(x.to_s) }
   end
 
   def assert_paths(*paths)
@@ -47,7 +49,7 @@ class ViewLoadPathsTest < ActionController::TestCase
   end
 
   def test_controller_appends_view_path_correctly
-    @controller.append_view_path 'foo'
+    @controller.append_view_path "foo"
     assert_paths(FIXTURE_LOAD_PATH, "foo")
 
     @controller.append_view_path(%w(bar baz))
@@ -58,7 +60,7 @@ class ViewLoadPathsTest < ActionController::TestCase
   end
 
   def test_controller_prepends_view_path_correctly
-    @controller.prepend_view_path 'baz'
+    @controller.prepend_view_path "baz"
     assert_paths("baz", FIXTURE_LOAD_PATH)
 
     @controller.prepend_view_path(%w(foo bar))
@@ -72,7 +74,7 @@ class ViewLoadPathsTest < ActionController::TestCase
     @controller.instance_variable_set :@template, ActionView::Base.new(TestController.view_paths, {}, @controller)
     class_view_paths = TestController.view_paths
 
-    @controller.append_view_path 'foo'
+    @controller.append_view_path "foo"
     assert_paths FIXTURE_LOAD_PATH, "foo"
 
     @controller.append_view_path(%w(bar baz))
@@ -84,7 +86,7 @@ class ViewLoadPathsTest < ActionController::TestCase
     @controller.instance_variable_set :@template, ActionView::Base.new(TestController.view_paths, {}, @controller)
     class_view_paths = TestController.view_paths
 
-    @controller.prepend_view_path 'baz'
+    @controller.prepend_view_path "baz"
     assert_paths "baz", FIXTURE_LOAD_PATH
 
     @controller.prepend_view_path(%w(foo bar))
@@ -131,10 +133,8 @@ class ViewLoadPathsTest < ActionController::TestCase
             "Decorated body",
             template.identifier,
             template.handler,
-            {
-              :virtual_path => template.virtual_path,
-              :format => template.formats
-            }
+              virtual_path: template.virtual_path,
+              format: template.formats
           )
         end
       end
@@ -157,14 +157,14 @@ class ViewLoadPathsTest < ActionController::TestCase
       class C < ActionController::Base; end
     }
 
-    A.view_paths = ['a/path']
+    A.view_paths = ["a/path"]
 
     assert_paths A, "a/path"
     assert_paths A, *B.view_paths
     assert_paths C, *original_load_paths
 
     C.view_paths = []
-    assert_nothing_raised { C.append_view_path 'c/path' }
+    assert_nothing_raised { C.append_view_path "c/path" }
     assert_paths C, "c/path"
   end
 
diff --git a/actionview/test/active_record_unit.rb b/actionview/test/active_record_unit.rb
index f9e94413b5..7f48b515a0 100644
--- a/actionview/test/active_record_unit.rb
+++ b/actionview/test/active_record_unit.rb
@@ -1,4 +1,6 @@
-require 'abstract_unit'
+# frozen_string_literal: true
+
+require "abstract_unit"
 
 # Define the essentials
 class ActiveRecordTestConnector
@@ -13,10 +15,10 @@ end
 # Try to grab AR
 unless defined?(ActiveRecord) && defined?(FixtureSet)
   begin
-    PATH_TO_AR = "#{File.dirname(__FILE__)}/../../activerecord/lib"
+    PATH_TO_AR = File.expand_path("../../activerecord/lib", __dir__)
     raise LoadError, "#{PATH_TO_AR} doesn't exist" unless File.directory?(PATH_TO_AR)
     $LOAD_PATH.unshift PATH_TO_AR
-    require 'active_record'
+    require "active_record"
   rescue LoadError => e
     $stderr.print "Failed to load Active Record. Skipping Active Record assertion tests: #{e}"
     ActiveRecordTestConnector.able_to_connect = false
@@ -24,12 +26,11 @@ unless defined?(ActiveRecord) && defined?(FixtureSet)
 end
 $stderr.flush
 
-
 # Define the rest of the connector
 class ActiveRecordTestConnector
   class << self
     def setup
-      unless self.connected || !self.able_to_connect
+      unless connected || !able_to_connect
         setup_connection
         load_schema
         require_fixture_models
@@ -37,21 +38,21 @@ class ActiveRecordTestConnector
       end
     rescue Exception => e  # errors from ActiveRecord setup
       $stderr.puts "\nSkipping ActiveRecord assertion tests: #{e}"
-      #$stderr.puts "  #{e.backtrace.join("\n  ")}\n"
+      # $stderr.puts "  #{e.backtrace.join("\n  ")}\n"
       self.able_to_connect = false
     end
 
     private
       def setup_connection
         if Object.const_defined?(:ActiveRecord)
-          defaults = { :database => ':memory:' }
-          adapter = defined?(JRUBY_VERSION) ? 'jdbcsqlite3' : 'sqlite3'
-          options = defaults.merge :adapter => adapter, :timeout => 500
+          defaults = { database: ":memory:" }
+          adapter = defined?(JRUBY_VERSION) ? "jdbcsqlite3" : "sqlite3"
+          options = defaults.merge adapter: adapter, timeout: 500
           ActiveRecord::Base.establish_connection(options)
-          ActiveRecord::Base.configurations = { 'sqlite3_ar_integration' => options }
+          ActiveRecord::Base.configurations = { "sqlite3_ar_integration" => options }
           ActiveRecord::Base.connection
 
-          Object.send(:const_set, :QUOTED_TYPE, ActiveRecord::Base.connection.quote_column_name('type')) unless Object.const_defined?(:QUOTED_TYPE)
+          Object.send(:const_set, :QUOTED_TYPE, ActiveRecord::Base.connection.quote_column_name("type")) unless Object.const_defined?(:QUOTED_TYPE)
         else
           raise "Can't setup connection since ActiveRecord isn't loaded."
         end
@@ -59,13 +60,13 @@ class ActiveRecordTestConnector
 
       # Load actionpack sqlite3 tables
       def load_schema
-        File.read(File.dirname(__FILE__) + "/fixtures/db_definitions/sqlite.sql").split(';').each do |sql|
+        File.read(File.expand_path("fixtures/db_definitions/sqlite.sql", __dir__)).split(";").each do |sql|
           ActiveRecord::Base.connection.execute(sql) unless sql.blank?
         end
       end
 
       def require_fixture_models
-        Dir.glob(File.dirname(__FILE__) + "/fixtures/*.rb").each {|f| require f}
+        Dir.glob(File.expand_path("fixtures/*.rb", __dir__)).each { |f| require f }
       end
   end
 end
diff --git a/actionview/test/activerecord/controller_runtime_test.rb b/actionview/test/activerecord/controller_runtime_test.rb
index af91348d76..42b171ea07 100644
--- a/actionview/test/activerecord/controller_runtime_test.rb
+++ b/actionview/test/activerecord/controller_runtime_test.rb
@@ -1,19 +1,21 @@
-require 'active_record_unit'
-require 'active_record/railties/controller_runtime'
-require 'fixtures/project'
-require 'active_support/log_subscriber/test_helper'
-require 'action_controller/log_subscriber'
+# frozen_string_literal: true
+
+require "active_record_unit"
+require "active_record/railties/controller_runtime"
+require "fixtures/project"
+require "active_support/log_subscriber/test_helper"
+require "action_controller/log_subscriber"
 
 ActionController::Base.include(ActiveRecord::Railties::ControllerRuntime)
 
 class ControllerRuntimeLogSubscriberTest < ActionController::TestCase
   class LogSubscriberController < ActionController::Base
     def show
-      render :inline => "<%= Project.all %>"
+      render inline: "<%= Project.all %>"
     end
 
     def zero
-      render :inline => "Zero DB runtime"
+      render inline: "Zero DB runtime"
     end
 
     def create
@@ -24,11 +26,11 @@ class ControllerRuntimeLogSubscriberTest < ActionController::TestCase
 
     def redirect
       Project.all
-      redirect_to :action => 'show'
+      redirect_to action: "show"
     end
 
     def db_after_render
-      render :inline => "Hello world"
+      render inline: "Hello world"
       Project.all
       ActiveRecord::LogSubscriber.runtime += 100
     end
@@ -38,8 +40,8 @@ class ControllerRuntimeLogSubscriberTest < ActionController::TestCase
   tests LogSubscriberController
 
   def setup
-    super
     @old_logger = ActionController::Base.logger
+    super
     ActionController::LogSubscriber.attach_to :action_controller
   end
 
@@ -67,7 +69,7 @@ class ControllerRuntimeLogSubscriberTest < ActionController::TestCase
     wait
 
     assert_equal 2, @logger.logged(:info).size
-    assert_match(/\(Views: [\d.]+ms \| ActiveRecord: 0.0ms\)/, @logger.logged(:info)[1])
+    assert_match(/\(Views: [\d.]+ms \| ActiveRecord: 0\.0ms\)/, @logger.logged(:info)[1])
   end
 
   def test_log_with_active_record_when_post
diff --git a/actionview/test/activerecord/debug_helper_test.rb b/actionview/test/activerecord/debug_helper_test.rb
index ed1c08e134..4be1023733 100644
--- a/actionview/test/activerecord/debug_helper_test.rb
+++ b/actionview/test/activerecord/debug_helper_test.rb
@@ -1,5 +1,7 @@
-require 'active_record_unit'
-require 'nokogiri'
+# frozen_string_literal: true
+
+require "active_record_unit"
+require "nokogiri"
 
 class DebugHelperTest < ActionView::TestCase
   def test_debug
@@ -11,7 +13,7 @@ class DebugHelperTest < ActionView::TestCase
   end
 
   def test_debug_with_marshal_error
-    obj = -> { }
+    obj = -> {}
     assert_match obj.inspect, Nokogiri.XML(debug(obj)).content
   end
 end
diff --git a/actionview/test/activerecord/form_helper_activerecord_test.rb b/actionview/test/activerecord/form_helper_activerecord_test.rb
index 2769b97445..1472ee8def 100644
--- a/actionview/test/activerecord/form_helper_activerecord_test.rb
+++ b/actionview/test/activerecord/form_helper_activerecord_test.rb
@@ -1,6 +1,8 @@
-require 'active_record_unit'
-require 'fixtures/project'
-require 'fixtures/developer'
+# frozen_string_literal: true
+
+require "active_record_unit"
+require "fixtures/project"
+require "fixtures/developer"
 
 class FormHelperActiveRecordTest < ActionView::TestCase
   tests ActionView::Helpers::FormHelper
@@ -39,50 +41,50 @@ class FormHelperActiveRecordTest < ActionView::TestCase
 
   def test_nested_fields_for_with_child_index_option_override_on_a_nested_attributes_collection_association
     form_for(@developer) do |f|
-      concat f.fields_for(:projects, @developer.projects.first, :child_index => 'abc') { |cf|
+      concat f.fields_for(:projects, @developer.projects.first, child_index: "abc") { |cf|
         concat cf.text_field(:name)
       }
     end
 
-    expected = whole_form('/developers/123', 'edit_developer_123', 'edit_developer', :method => 'patch') do
-      '<input id="developer_projects_attributes_abc_name" name="developer[projects_attributes][abc][name]" type="text" value="project #321" />' +
+    expected = whole_form("/developers/123", "edit_developer_123", "edit_developer", method: "patch") do
+      '<input id="developer_projects_attributes_abc_name" name="developer[projects_attributes][abc][name]" type="text" value="project #321" />' \
           '<input id="developer_projects_attributes_abc_id" name="developer[projects_attributes][abc][id]" type="hidden" value="321" />'
     end
 
     assert_dom_equal expected, output_buffer
   end
 
-  protected
+  private
+
+    def hidden_fields(method = nil)
+      txt = %{<input name="utf8" type="hidden" value="&#x2713;" />}.dup
 
-  def hidden_fields(method = nil)
-    txt = %{<input name="utf8" type="hidden" value="&#x2713;" />}
+      if method && !%w(get post).include?(method.to_s)
+        txt << %{<input name="_method" type="hidden" value="#{method}" />}
+      end
 
-    if method && !%w(get post).include?(method.to_s)
-      txt << %{<input name="_method" type="hidden" value="#{method}" />}
+      txt
     end
 
-    txt
-  end
+    def form_text(action = "/", id = nil, html_class = nil, remote = nil, multipart = nil, method = nil)
+      txt =  %{<form accept-charset="UTF-8" action="#{action}"}.dup
+      txt << %{ enctype="multipart/form-data"} if multipart
+      txt << %{ data-remote="true"} if remote
+      txt << %{ class="#{html_class}"} if html_class
+      txt << %{ id="#{id}"} if id
+      method = method.to_s == "get" ? "get" : "post"
+      txt << %{ method="#{method}">}
+    end
 
-  def form_text(action = "/", id = nil, html_class = nil, remote = nil, multipart = nil, method = nil)
-    txt =  %{<form accept-charset="UTF-8" action="#{action}"}
-    txt << %{ enctype="multipart/form-data"} if multipart
-    txt << %{ data-remote="true"} if remote
-    txt << %{ class="#{html_class}"} if html_class
-    txt << %{ id="#{id}"} if id
-    method = method.to_s == "get" ? "get" : "post"
-    txt << %{ method="#{method}">}
-  end
+    def whole_form(action = "/", id = nil, html_class = nil, options = nil)
+      contents = block_given? ? yield : ""
 
-  def whole_form(action = "/", id = nil, html_class = nil, options = nil)
-    contents = block_given? ? yield : ""
+      if options.is_a?(Hash)
+        method, remote, multipart = options.values_at(:method, :remote, :multipart)
+      else
+        method = options
+      end
 
-    if options.is_a?(Hash)
-      method, remote, multipart = options.values_at(:method, :remote, :multipart)
-    else
-      method = options
+      form_text(action, id, html_class, remote, multipart, method) + hidden_fields(method) + contents + "</form>"
     end
-
-    form_text(action, id, html_class, remote, multipart, method) + hidden_fields(method) + contents + "</form>"
-  end
 end
diff --git a/actionview/test/activerecord/polymorphic_routes_test.rb b/actionview/test/activerecord/polymorphic_routes_test.rb
index 34b2698c7f..4b931f793f 100644
--- a/actionview/test/activerecord/polymorphic_routes_test.rb
+++ b/actionview/test/activerecord/polymorphic_routes_test.rb
@@ -1,28 +1,30 @@
-require 'active_record_unit'
-require 'fixtures/project'
+# frozen_string_literal: true
+
+require "active_record_unit"
+require "fixtures/project"
 
 class Task < ActiveRecord::Base
-  self.table_name = 'projects'
+  self.table_name = "projects"
 end
 
 class Step < ActiveRecord::Base
-  self.table_name = 'projects'
+  self.table_name = "projects"
 end
 
 class Bid < ActiveRecord::Base
-  self.table_name = 'projects'
+  self.table_name = "projects"
 end
 
 class Tax < ActiveRecord::Base
-  self.table_name = 'projects'
+  self.table_name = "projects"
 end
 
 class Fax < ActiveRecord::Base
-  self.table_name = 'projects'
+  self.table_name = "projects"
 end
 
 class Series < ActiveRecord::Base
-  self.table_name = 'projects'
+  self.table_name = "projects"
 end
 
 class ModelDelegator
@@ -41,17 +43,17 @@ class ModelDelegate
   end
 
   def to_param
-    'overridden'
+    "overridden"
   end
 end
 
-module Blog
+module Weblog
   class Post < ActiveRecord::Base
-    self.table_name = 'projects'
+    self.table_name = "projects"
   end
 
   class Blog < ActiveRecord::Base
-    self.table_name = 'projects'
+    self.table_name = "projects"
   end
 
   def self.use_relative_model_naming?
@@ -61,7 +63,7 @@ end
 
 class PolymorphicRoutesTest < ActionController::TestCase
   include SharedTestRoutes.url_helpers
-  self.default_url_options[:host] = 'example.com'
+  default_url_options[:host] = "example.com"
 
   def setup
     @project = Project.new
@@ -72,22 +74,21 @@ class PolymorphicRoutesTest < ActionController::TestCase
     @fax = Fax.new
     @delegator = ModelDelegator.new
     @series = Series.new
-    @blog_post = Blog::Post.new
-    @blog_blog = Blog::Blog.new
+    @blog_post = Weblog::Post.new
+    @blog_blog = Weblog::Blog.new
   end
 
   def assert_url(url, args)
     host = self.class.default_url_options[:host]
 
-    assert_equal url.sub(/http:\/\/#{host}/, ''), polymorphic_path(args)
+    assert_equal url.sub(/http:\/\/#{host}/, ""), polymorphic_path(args)
     assert_equal url, polymorphic_url(args)
     assert_equal url, url_for(args)
   end
 
   def test_string
     with_test_routes do
-      # FIXME: why are these different? Symbol case passes through to
-      # `polymorphic_url`, but the String case doesn't.
+      assert_equal "/projects", polymorphic_path("projects")
       assert_equal "http://example.com/projects", polymorphic_url("projects")
       assert_equal "projects", url_for("projects")
     end
@@ -95,7 +96,7 @@ class PolymorphicRoutesTest < ActionController::TestCase
 
   def test_string_with_options
     with_test_routes do
-      assert_equal "http://example.com/projects?id=10", polymorphic_url("projects", :id => 10)
+      assert_equal "http://example.com/projects?id=10", polymorphic_url("projects", id: 10)
     end
   end
 
@@ -107,7 +108,7 @@ class PolymorphicRoutesTest < ActionController::TestCase
 
   def test_symbol_with_options
     with_test_routes do
-      assert_equal "http://example.com/projects?id=10", polymorphic_url(:projects, :id => 10)
+      assert_equal "http://example.com/projects?id=10", polymorphic_url(:projects, id: 10)
     end
   end
 
@@ -179,7 +180,7 @@ class PolymorphicRoutesTest < ActionController::TestCase
   def test_with_nil_id
     with_test_routes do
       exception = assert_raise ArgumentError do
-        polymorphic_url({ :id => nil })
+        polymorphic_url(id: nil)
       end
       assert_equal "Nil location provided. Can't build URI.", exception.message
     end
@@ -233,8 +234,8 @@ class PolymorphicRoutesTest < ActionController::TestCase
 
   def test_class_with_options
     with_test_routes do
-      assert_equal "http://example.com/projects?foo=bar", polymorphic_url(@project.class, { :foo => :bar })
-      assert_equal "/projects?foo=bar", polymorphic_path(@project.class, { :foo => :bar })
+      assert_equal "http://example.com/projects?foo=bar", polymorphic_url(@project.class, foo: :bar)
+      assert_equal "/projects?foo=bar", polymorphic_path(@project.class, foo: :bar)
     end
   end
 
@@ -274,7 +275,7 @@ class PolymorphicRoutesTest < ActionController::TestCase
 
   def test_with_record_and_action
     with_test_routes do
-      assert_equal "http://example.com/projects/new", polymorphic_url(@project, :action => 'new')
+      assert_equal "http://example.com/projects/new", polymorphic_url(@project, action: "new")
     end
   end
 
@@ -303,35 +304,35 @@ class PolymorphicRoutesTest < ActionController::TestCase
   def test_url_helper_prefixed_with_edit_with_url_options
     with_test_routes do
       @project.save
-      assert_equal "http://example.com/projects/#{@project.id}/edit?param1=10", edit_polymorphic_url(@project, :param1 => '10')
+      assert_equal "http://example.com/projects/#{@project.id}/edit?param1=10", edit_polymorphic_url(@project, param1: "10")
     end
   end
 
   def test_url_helper_with_url_options
     with_test_routes do
       @project.save
-      assert_equal "http://example.com/projects/#{@project.id}?param1=10", polymorphic_url(@project, :param1 => '10')
+      assert_equal "http://example.com/projects/#{@project.id}?param1=10", polymorphic_url(@project, param1: "10")
     end
   end
 
   def test_format_option
     with_test_routes do
       @project.save
-      assert_equal "http://example.com/projects/#{@project.id}.pdf", polymorphic_url(@project, :format => :pdf)
+      assert_equal "http://example.com/projects/#{@project.id}.pdf", polymorphic_url(@project, format: :pdf)
     end
   end
 
   def test_format_option_with_url_options
     with_test_routes do
       @project.save
-      assert_equal "http://example.com/projects/#{@project.id}.pdf?param1=10", polymorphic_url(@project, :format => :pdf, :param1 => '10')
+      assert_equal "http://example.com/projects/#{@project.id}.pdf?param1=10", polymorphic_url(@project, format: :pdf, param1: "10")
     end
   end
 
   def test_id_and_format_option
     with_test_routes do
       @project.save
-      assert_equal "http://example.com/projects/#{@project.id}.pdf", polymorphic_url(:id => @project, :format => :pdf)
+      assert_equal "http://example.com/projects/#{@project.id}.pdf", polymorphic_url(id: @project, format: :pdf)
     end
   end
 
@@ -373,7 +374,7 @@ class PolymorphicRoutesTest < ActionController::TestCase
 
   def test_new_with_array_and_namespace
     with_admin_test_routes do
-      assert_equal "http://example.com/admin/projects/new", polymorphic_url([:admin, @project], :action => 'new')
+      assert_equal "http://example.com/admin/projects/new", polymorphic_url([:admin, @project], action: "new")
     end
   end
 
@@ -426,7 +427,7 @@ class PolymorphicRoutesTest < ActionController::TestCase
     with_test_routes do
       @project.save
       @task.save
-      assert_equal "http://example.com/projects/#{@project.id}/bid/tasks/#{@task.id}.pdf", polymorphic_url([@project, :bid, @task], :format => :pdf)
+      assert_equal "http://example.com/projects/#{@project.id}/bid/tasks/#{@task.id}.pdf", polymorphic_url([@project, :bid, @task], format: :pdf)
     end
   end
 
@@ -474,13 +475,13 @@ class PolymorphicRoutesTest < ActionController::TestCase
   def test_with_hash
     with_test_routes do
       @project.save
-      assert_equal "http://example.com/projects/#{@project.id}", polymorphic_url(:id => @project)
+      assert_equal "http://example.com/projects/#{@project.id}", polymorphic_url(id: @project)
     end
   end
 
   def test_polymorphic_path_accepts_options
     with_test_routes do
-      assert_equal "/projects/new", polymorphic_path(@project, :action => 'new')
+      assert_equal "/projects/new", polymorphic_path(@project, action: "new")
     end
   end
 
@@ -493,7 +494,7 @@ class PolymorphicRoutesTest < ActionController::TestCase
       object_array = [:admin, @project, @task]
       original_args = [object_array.dup, options.dup]
 
-      assert_no_difference('object_array.size') { polymorphic_path(object_array, options) }
+      assert_no_difference("object_array.size") { polymorphic_path(object_array, options) }
       assert_equal original_args, [object_array, options]
     end
   end
@@ -527,7 +528,7 @@ class PolymorphicRoutesTest < ActionController::TestCase
 
   def test_with_irregular_plural_record_and_action
     with_test_routes do
-      assert_equal "http://example.com/taxes/new", polymorphic_url(@tax, :action => 'new')
+      assert_equal "http://example.com/taxes/new", polymorphic_url(@tax, action: "new")
     end
   end
 
@@ -561,7 +562,7 @@ class PolymorphicRoutesTest < ActionController::TestCase
 
   def test_new_with_irregular_plural_array_and_namespace
     with_admin_test_routes do
-      assert_equal "http://example.com/admin/taxes/new", polymorphic_url([:admin, @tax], :action => 'new')
+      assert_equal "http://example.com/admin/taxes/new", polymorphic_url([:admin, @tax], action: "new")
     end
   end
 
@@ -598,7 +599,7 @@ class PolymorphicRoutesTest < ActionController::TestCase
     end
   end
 
- # Tests for uncountable names
+  # Tests for uncountable names
   def test_uncountable_resource
     with_test_routes do
       @series.save
@@ -622,7 +623,7 @@ class PolymorphicRoutesTest < ActionController::TestCase
   def with_namespaced_routes(name)
     with_routing do |set|
       set.draw do
-        scope(:module => name) do
+        scope(module: name) do
           resources :blogs do
             resources :posts do
               resources :faxes
@@ -728,6 +729,52 @@ class PolymorphicPathRoutesTest < PolymorphicRoutesTest
   def assert_url(url, args)
     host = self.class.default_url_options[:host]
 
-    assert_equal url.sub(/http:\/\/#{host}/, ''), url_for(args)
+    assert_equal url.sub(/http:\/\/#{host}/, ""), url_for(args)
+  end
+end
+
+class DirectRoutesTest < ActionView::TestCase
+  class Linkable
+    attr_reader :id
+
+    def self.name
+      super.demodulize
+    end
+
+    def initialize(id)
+      @id = id
+    end
+
+    def linkable_type
+      self.class.name.underscore
+    end
+  end
+
+  class Category < Linkable; end
+  class Collection < Linkable; end
+  class Product < Linkable; end
+
+  Routes = ActionDispatch::Routing::RouteSet.new
+  Routes.draw do
+    resources :categories, :collections, :products
+    direct(:linkable) { |linkable| [:"#{linkable.linkable_type}", { id: linkable.id }] }
+  end
+
+  include Routes.url_helpers
+
+  def setup
+    @category = Category.new("1")
+    @collection = Collection.new("2")
+    @product = Product.new("3")
+  end
+
+  def test_direct_routes
+    assert_equal "/categories/1", linkable_path(@category)
+    assert_equal "/collections/2", linkable_path(@collection)
+    assert_equal "/products/3", linkable_path(@product)
+
+    assert_equal "http://test.host/categories/1", linkable_url(@category)
+    assert_equal "http://test.host/collections/2", linkable_url(@collection)
+    assert_equal "http://test.host/products/3", linkable_url(@product)
   end
 end
diff --git a/actionview/test/activerecord/relation_cache_test.rb b/actionview/test/activerecord/relation_cache_test.rb
index 8e97417b94..bd0cd10eaf 100644
--- a/actionview/test/activerecord/relation_cache_test.rb
+++ b/actionview/test/activerecord/relation_cache_test.rb
@@ -1,18 +1,23 @@
-require 'active_record_unit'
+# frozen_string_literal: true
 
-class RelationCacheTest <  ActionView::TestCase
+require "active_record_unit"
+
+class RelationCacheTest < ActionView::TestCase
   tests ActionView::Helpers::CacheHelper
 
   def setup
-    @virtual_path = "path"
+    view_paths     = ActionController::Base.view_paths
+    lookup_context = ActionView::LookupContext.new(view_paths, {}, ["test"])
+    @view_renderer = ActionView::Renderer.new(lookup_context)
+    @virtual_path  = "path"
+
     controller.cache_store = ActiveSupport::Cache::MemoryStore.new
   end
 
   def test_cache_relation_other
-    cache(Project.all){ concat("Hello World") }
-    assert_equal "Hello World", controller.cache_store.read("views/projects-#{Project.count}/")
+    cache(Project.all) { concat("Hello World") }
+    assert_equal "Hello World", controller.cache_store.read("views/path/projects-#{Project.count}")
   end
 
   def view_cache_dependencies; end
-
 end
diff --git a/actionview/test/activerecord/render_partial_with_record_identification_test.rb b/actionview/test/activerecord/render_partial_with_record_identification_test.rb
index 9772ebb39e..3a698fa42e 100644
--- a/actionview/test/activerecord/render_partial_with_record_identification_test.rb
+++ b/actionview/test/activerecord/render_partial_with_record_identification_test.rb
@@ -1,48 +1,40 @@
-require 'active_record_unit'
+# frozen_string_literal: true
+
+require "active_record_unit"
 
 class RenderPartialWithRecordIdentificationController < ActionController::Base
   def render_with_has_many_and_belongs_to_association
     @developer = Developer.find(1)
-    render :partial => @developer.projects
+    render partial: @developer.projects
   end
 
   def render_with_has_many_association
     @topic = Topic.find(1)
-    render :partial => @topic.replies
+    render partial: @topic.replies
   end
 
   def render_with_scope
-    render :partial => Reply.base
-  end
-
-  def render_with_has_many_through_association
-    @developer = Developer.first
-    render :partial => @developer.topics
+    render partial: Reply.base
   end
 
   def render_with_has_one_association
     @company = Company.find(1)
-    render :partial => @company.mascot
-  end
-
-  def render_with_belongs_to_association
-    @reply = Reply.find(1)
-    render :partial => @reply.topic
+    render partial: @company.mascot
   end
 
   def render_with_record
     @developer = Developer.first
-    render :partial => @developer
+    render partial: @developer
   end
 
   def render_with_record_collection
     @developers = Developer.all
-    render :partial => @developers
+    render partial: @developers
   end
 
   def render_with_record_collection_and_spacer_template
     @developer = Developer.find(1)
-    render :partial => @developer.projects, :spacer_template => 'test/partial_only'
+    render partial: @developer.projects, spacer_template: "test/partial_only"
   end
 end
 
@@ -57,27 +49,27 @@ class RenderPartialWithRecordIdentificationTest < ActiveRecordTestCase
 
   def test_rendering_partial_with_has_many_association
     get :render_with_has_many_association
-    assert_equal 'Birdman is better!', @response.body
+    assert_equal "Birdman is better!", @response.body
   end
 
   def test_rendering_partial_with_scope
     get :render_with_scope
-    assert_equal 'Birdman is better!Nuh uh!', @response.body
+    assert_equal "Birdman is better!Nuh uh!", @response.body
   end
 
   def test_render_with_record
     get :render_with_record
-    assert_equal 'David', @response.body
+    assert_equal "David", @response.body
   end
 
   def test_render_with_record_collection
     get :render_with_record_collection
-    assert_equal 'DavidJamisfixture_3fixture_4fixture_5fixture_6fixture_7fixture_8fixture_9fixture_10Jamis', @response.body
+    assert_equal "DavidJamisfixture_3fixture_4fixture_5fixture_6fixture_7fixture_8fixture_9fixture_10Jamis", @response.body
   end
 
   def test_render_with_record_collection_and_spacer_template
     get :render_with_record_collection_and_spacer_template
-    assert_equal Developer.find(1).projects.map(&:name).join('only partial'), @response.body
+    assert_equal Developer.find(1).projects.map(&:name).join("only partial"), @response.body
   end
 
   def test_rendering_partial_with_has_one_association
@@ -87,7 +79,7 @@ class RenderPartialWithRecordIdentificationTest < ActiveRecordTestCase
   end
 end
 
-class Game < Struct.new(:name, :id)
+Game = Struct.new(:name, :id) do
   extend ActiveModel::Naming
   include ActiveModel::Conversion
   def to_param
@@ -98,22 +90,22 @@ end
 module Fun
   class NestedController < ActionController::Base
     def render_with_record_in_nested_controller
-      render :partial => Game.new("Pong")
+      render partial: Game.new("Pong")
     end
 
     def render_with_record_collection_in_nested_controller
-      render :partial => [ Game.new("Pong"), Game.new("Tank") ]
+      render partial: [ Game.new("Pong"), Game.new("Tank") ]
     end
   end
 
   module Serious
     class NestedDeeperController < ActionController::Base
       def render_with_record_in_deeper_nested_controller
-        render :partial => Game.new("Chess")
+        render partial: Game.new("Chess")
       end
 
       def render_with_record_collection_in_deeper_nested_controller
-        render :partial => [ Game.new("Chess"), Game.new("Sudoku"), Game.new("Solitaire") ]
+        render partial: [ Game.new("Chess"), Game.new("Sudoku"), Game.new("Solitaire") ]
       end
     end
   end
diff --git a/actionview/test/fixtures/actionpack/layouts/builder.builder b/actionview/test/fixtures/actionpack/layouts/builder.builder
index 7c7d4b2dd1..c55488edd0 100644
--- a/actionview/test/fixtures/actionpack/layouts/builder.builder
+++ b/actionview/test/fixtures/actionpack/layouts/builder.builder
@@ -1,3 +1,3 @@
 xml.wrapper do
   xml << yield
-end
\ No newline at end of file
+end
diff --git a/actionview/test/fixtures/actionpack/test/_hello.builder b/actionview/test/fixtures/actionpack/test/_hello.builder
index ef52f632d1..fc72df16d0 100644
--- a/actionview/test/fixtures/actionpack/test/_hello.builder
+++ b/actionview/test/fixtures/actionpack/test/_hello.builder
@@ -1 +1 @@
-xm.hello
\ No newline at end of file
+xm.hello
diff --git a/actionview/test/fixtures/actionpack/test/formatted_xml_erb.builder b/actionview/test/fixtures/actionpack/test/formatted_xml_erb.builder
index 14fd3549fb..f98aaa34a5 100644
--- a/actionview/test/fixtures/actionpack/test/formatted_xml_erb.builder
+++ b/actionview/test/fixtures/actionpack/test/formatted_xml_erb.builder
@@ -1 +1 @@
-xml.test 'failed'
\ No newline at end of file
+xml.test "failed"
diff --git a/actionview/test/fixtures/actionpack/test/hello.builder b/actionview/test/fixtures/actionpack/test/hello.builder
index a471553941..b8ab17ad5b 100644
--- a/actionview/test/fixtures/actionpack/test/hello.builder
+++ b/actionview/test/fixtures/actionpack/test/hello.builder
@@ -1,4 +1,4 @@
 xml.html do
   xml.p "Hello #{@name}"
-  xml << render(:file => "test/greeting")
-end
\ No newline at end of file
+  xml << render(file: "test/greeting")
+end
diff --git a/actionview/test/fixtures/actionpack/test/hello_world_container.builder b/actionview/test/fixtures/actionpack/test/hello_world_container.builder
index e48d75c405..24032ab5e0 100644
--- a/actionview/test/fixtures/actionpack/test/hello_world_container.builder
+++ b/actionview/test/fixtures/actionpack/test/hello_world_container.builder
@@ -1,3 +1,3 @@
 xml.test do
-  render :partial => 'hello', :locals => { :xm => xml }
-end
\ No newline at end of file
+  render partial: "hello", locals: { xm: xml }
+end
diff --git a/actionview/test/fixtures/actionpack/test/hello_xml_world.builder b/actionview/test/fixtures/actionpack/test/hello_xml_world.builder
index e7081b89fe..d16bb6b5cb 100644
--- a/actionview/test/fixtures/actionpack/test/hello_xml_world.builder
+++ b/actionview/test/fixtures/actionpack/test/hello_xml_world.builder
@@ -8,4 +8,4 @@ xml.html do
     xml.p "monks"
     xml.p "wiseguys"
   end
-end
\ No newline at end of file
+end
diff --git a/actionview/test/fixtures/actionpack/test/non_erb_block_content_for.builder b/actionview/test/fixtures/actionpack/test/non_erb_block_content_for.builder
index d539a425a4..cd65da751b 100644
--- a/actionview/test/fixtures/actionpack/test/non_erb_block_content_for.builder
+++ b/actionview/test/fixtures/actionpack/test/non_erb_block_content_for.builder
@@ -1,4 +1,4 @@
 content_for :title do
-  'Putting stuff in the title!'
+  "Putting stuff in the title!"
 end
 xml << "Great stuff!"
diff --git a/actionview/test/fixtures/comments/empty.html+grid.erb b/actionview/test/fixtures/comments/empty.html+grid.erb
new file mode 100644
index 0000000000..dc3fa32a81
--- /dev/null
+++ b/actionview/test/fixtures/comments/empty.html+grid.erb
@@ -0,0 +1 @@
+<h1>No Comment</h1>
diff --git a/actionview/test/fixtures/comments/empty.html.builder b/actionview/test/fixtures/comments/empty.html.builder
index 2b0c7207a3..12d6fdd9a5 100644
--- a/actionview/test/fixtures/comments/empty.html.builder
+++ b/actionview/test/fixtures/comments/empty.html.builder
@@ -1 +1 @@
-xml.h1 'No Comment'
\ No newline at end of file
+xml.h1 "No Comment"
diff --git a/actionview/test/fixtures/company.rb b/actionview/test/fixtures/company.rb
index f3ac3642fa..93afdd5472 100644
--- a/actionview/test/fixtures/company.rb
+++ b/actionview/test/fixtures/company.rb
@@ -1,9 +1,11 @@
+# frozen_string_literal: true
+
 class Company < ActiveRecord::Base
   has_one :mascot
   self.sequence_name = :companies_nonstd_seq
 
   validates_presence_of :name
   def validate
-    errors.add('rating', 'rating should not be 2') if rating == 2
+    errors.add("rating", "rating should not be 2") if rating == 2
   end
 end
diff --git a/actionview/test/fixtures/developer.rb b/actionview/test/fixtures/developer.rb
index 8b3f0a8039..cb7ee49eed 100644
--- a/actionview/test/fixtures/developer.rb
+++ b/actionview/test/fixtures/developer.rb
@@ -1,6 +1,8 @@
+# frozen_string_literal: true
+
 class Developer < ActiveRecord::Base
   has_and_belongs_to_many :projects
   has_many :replies
-  has_many :topics, :through => :replies
+  has_many :topics, through: :replies
   accepts_nested_attributes_for :projects
 end
diff --git a/actionview/test/fixtures/helpers/abc_helper.rb b/actionview/test/fixtures/helpers/abc_helper.rb
index cf2774bb5f..999b9b5c6e 100644
--- a/actionview/test/fixtures/helpers/abc_helper.rb
+++ b/actionview/test/fixtures/helpers/abc_helper.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module AbcHelper
   def bare_a() end
 end
diff --git a/actionview/test/fixtures/helpers/helpery_test_helper.rb b/actionview/test/fixtures/helpers/helpery_test_helper.rb
index a4f2951efa..9836143848 100644
--- a/actionview/test/fixtures/helpers/helpery_test_helper.rb
+++ b/actionview/test/fixtures/helpers/helpery_test_helper.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module HelperyTestHelper
   def helpery_test
     "Default"
diff --git a/actionview/test/fixtures/helpers_missing/invalid_require_helper.rb b/actionview/test/fixtures/helpers_missing/invalid_require_helper.rb
index d8801e54d5..c77121046d 100644
--- a/actionview/test/fixtures/helpers_missing/invalid_require_helper.rb
+++ b/actionview/test/fixtures/helpers_missing/invalid_require_helper.rb
@@ -1,5 +1,6 @@
-require 'very_invalid_file_name'
+# frozen_string_literal: true
+
+require "very_invalid_file_name"
 
 module InvalidRequireHelper
 end
-
diff --git a/actionview/test/fixtures/layouts/streaming_with_locale.erb b/actionview/test/fixtures/layouts/streaming_with_locale.erb
new file mode 100644
index 0000000000..e1fdad2073
--- /dev/null
+++ b/actionview/test/fixtures/layouts/streaming_with_locale.erb
@@ -0,0 +1,2 @@
+layout.locale: <%= I18n.locale %>
+<%= yield %>
diff --git a/actionview/test/fixtures/mascot.rb b/actionview/test/fixtures/mascot.rb
index f9f1448b8f..26a2c7bbe1 100644
--- a/actionview/test/fixtures/mascot.rb
+++ b/actionview/test/fixtures/mascot.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Mascot < ActiveRecord::Base
   belongs_to :company
-end
\ No newline at end of file
+end
diff --git a/actionview/test/fixtures/project.rb b/actionview/test/fixtures/project.rb
index 404b12cbab..019ddb7aef 100644
--- a/actionview/test/fixtures/project.rb
+++ b/actionview/test/fixtures/project.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Project < ActiveRecord::Base
   has_and_belongs_to_many :developers, -> { uniq }
 
diff --git a/actionview/test/fixtures/reply.rb b/actionview/test/fixtures/reply.rb
index 047522c55b..b2b662e1b5 100644
--- a/actionview/test/fixtures/reply.rb
+++ b/actionview/test/fixtures/reply.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Reply < ActiveRecord::Base
   scope :base, -> { all }
   belongs_to :topic, -> { includes(:replies) }
diff --git a/actionview/test/fixtures/ruby_template.ruby b/actionview/test/fixtures/ruby_template.ruby
index 5097bce47c..93334610a8 100644
--- a/actionview/test/fixtures/ruby_template.ruby
+++ b/actionview/test/fixtures/ruby_template.ruby
@@ -1,2 +1,2 @@
-body = ""
+body = "".dup
 body << ["Hello", "from", "Ruby", "code"].join(" ")
diff --git a/actionview/test/fixtures/test/_builder_tag_nested_in_content_tag.erb b/actionview/test/fixtures/test/_builder_tag_nested_in_content_tag.erb
new file mode 100644
index 0000000000..ddad7ec3ac
--- /dev/null
+++ b/actionview/test/fixtures/test/_builder_tag_nested_in_content_tag.erb
@@ -0,0 +1,3 @@
+<%= tag.p do %>
+  <%= tag.b 'Hello' %>
+<% end %>
diff --git a/actionview/test/fixtures/test/_cached_nested_cached_customer.erb b/actionview/test/fixtures/test/_cached_nested_cached_customer.erb
new file mode 100644
index 0000000000..01bf025cd3
--- /dev/null
+++ b/actionview/test/fixtures/test/_cached_nested_cached_customer.erb
@@ -0,0 +1,3 @@
+<% cache cached_customer do %>
+  <%= render partial: "test/cached_customer", locals: { cached_customer: cached_customer } %>
+<% end %>
diff --git a/actionview/test/fixtures/test/_nested_cached_customer.erb b/actionview/test/fixtures/test/_nested_cached_customer.erb
new file mode 100644
index 0000000000..f43adc94c9
--- /dev/null
+++ b/actionview/test/fixtures/test/_nested_cached_customer.erb
@@ -0,0 +1 @@
+<%= render partial: "test/cached_customer", locals: { cached_customer: cached_customer } %>
diff --git a/actionview/test/fixtures/test/_partial_iteration_1.erb b/actionview/test/fixtures/test/_partial_iteration_1.erb
new file mode 100644
index 0000000000..c0fdd4c22a
--- /dev/null
+++ b/actionview/test/fixtures/test/_partial_iteration_1.erb
@@ -0,0 +1 @@
+<%= defined?(partial_iteration_1_iteration) %>
diff --git a/actionview/test/fixtures/test/_partial_iteration_2.erb b/actionview/test/fixtures/test/_partial_iteration_2.erb
new file mode 100644
index 0000000000..50dd11db27
--- /dev/null
+++ b/actionview/test/fixtures/test/_partial_iteration_2.erb
@@ -0,0 +1 @@
+<%= defined?(partial_iteration_2_iteration) -%>
diff --git a/actionview/test/fixtures/test/_partial_with_variants.html+grid.erb b/actionview/test/fixtures/test/_partial_with_variants.html+grid.erb
new file mode 100644
index 0000000000..225363c8c3
--- /dev/null
+++ b/actionview/test/fixtures/test/_partial_with_variants.html+grid.erb
@@ -0,0 +1 @@
+<h1>Partial with variants</h1>
diff --git a/actionview/test/fixtures/test/hello.builder b/actionview/test/fixtures/test/hello.builder
index a471553941..b8ab17ad5b 100644
--- a/actionview/test/fixtures/test/hello.builder
+++ b/actionview/test/fixtures/test/hello.builder
@@ -1,4 +1,4 @@
 xml.html do
   xml.p "Hello #{@name}"
-  xml << render(:file => "test/greeting")
-end
\ No newline at end of file
+  xml << render(file: "test/greeting")
+end
diff --git a/actionview/test/fixtures/test/render_file_inspect_local_assigns.erb b/actionview/test/fixtures/test/render_file_inspect_local_assigns.erb
new file mode 100644
index 0000000000..aea5c351c5
--- /dev/null
+++ b/actionview/test/fixtures/test/render_file_inspect_local_assigns.erb
@@ -0,0 +1 @@
+<%= local_assigns.inspect.html_safe %>
\ No newline at end of file
diff --git a/actionview/test/fixtures/test/render_file_instance_variable.erb b/actionview/test/fixtures/test/render_file_instance_variable.erb
new file mode 100644
index 0000000000..5344ac8a66
--- /dev/null
+++ b/actionview/test/fixtures/test/render_file_instance_variable.erb
@@ -0,0 +1 @@
+<%= @foo %>
\ No newline at end of file
diff --git a/actionview/test/fixtures/test/render_file_unicode_local.erb b/actionview/test/fixtures/test/render_file_unicode_local.erb
new file mode 100644
index 0000000000..cbfd040a76
--- /dev/null
+++ b/actionview/test/fixtures/test/render_file_unicode_local.erb
@@ -0,0 +1 @@
+<%= 🎃 %>
\ No newline at end of file
diff --git a/actionview/test/fixtures/test/render_file_with_ruby_keyword_locals.erb b/actionview/test/fixtures/test/render_file_with_ruby_keyword_locals.erb
new file mode 100644
index 0000000000..7e3fe6c6d9
--- /dev/null
+++ b/actionview/test/fixtures/test/render_file_with_ruby_keyword_locals.erb
@@ -0,0 +1 @@
+The class is <%= local_assigns[:class] %>
\ No newline at end of file
diff --git a/actionview/test/fixtures/test/streaming_with_locale.erb b/actionview/test/fixtures/test/streaming_with_locale.erb
new file mode 100644
index 0000000000..b0f2b2f7e9
--- /dev/null
+++ b/actionview/test/fixtures/test/streaming_with_locale.erb
@@ -0,0 +1 @@
+view.locale: <%= I18n.locale %>
diff --git a/actionview/test/fixtures/test/test_template_with_delegation_reserved_keywords.erb b/actionview/test/fixtures/test/test_template_with_delegation_reserved_keywords.erb
new file mode 100644
index 0000000000..edfe52e422
--- /dev/null
+++ b/actionview/test/fixtures/test/test_template_with_delegation_reserved_keywords.erb
@@ -0,0 +1 @@
+<%= _ %> <%= arg %> <%= args %> <%= block %>
\ No newline at end of file
diff --git a/actionview/test/fixtures/topic.rb b/actionview/test/fixtures/topic.rb
index 9fa9746535..ff194ce567 100644
--- a/actionview/test/fixtures/topic.rb
+++ b/actionview/test/fixtures/topic.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Topic < ActiveRecord::Base
-  has_many :replies, :dependent => :destroy
+  has_many :replies, dependent: :destroy
 end
diff --git a/actionview/test/lib/controller/fake_models.rb b/actionview/test/lib/controller/fake_models.rb
index 65c68fc34a..f8b7ddaecc 100644
--- a/actionview/test/lib/controller/fake_models.rb
+++ b/actionview/test/lib/controller/fake_models.rb
@@ -1,12 +1,14 @@
+# frozen_string_literal: true
+
 require "active_model"
 
-class Customer < Struct.new(:name, :id)
+Customer = Struct.new(:name, :id) do
   extend ActiveModel::Naming
   include ActiveModel::Conversion
 
   undef_method :to_json
 
-  def to_xml(options={})
+  def to_xml(options = {})
     if options[:builder]
       options[:builder].name name
     else
@@ -14,7 +16,7 @@ class Customer < Struct.new(:name, :id)
     end
   end
 
-  def to_js(options={})
+  def to_js(options = {})
     "name: #{name.inspect}"
   end
   alias :to_text :to_js
@@ -26,12 +28,16 @@ class Customer < Struct.new(:name, :id)
   def persisted?
     id.present?
   end
-end
 
-class GoodCustomer < Customer
+  def cache_key
+    name.to_s
+  end
 end
 
-class Post < Struct.new(:title, :author_name, :body, :secret, :persisted, :written_on, :cost)
+class BadCustomer < Customer; end
+class GoodCustomer < Customer; end
+
+Post = Struct.new(:title, :author_name, :body, :secret, :persisted, :written_on, :cost) do
   extend ActiveModel::Naming
   include ActiveModel::Conversion
   extend ActiveModel::Translation
@@ -80,7 +86,7 @@ class Comment
   def to_key; id ? [id] : nil end
   def save; @id = 1; @post_id = 1 end
   def persisted?; @id.present? end
-  def to_param; @id.to_s; end
+  def to_param; @id && @id.to_s; end
   def name
     @id.nil? ? "new #{self.class.name.downcase}" : "#{self.class.name.downcase} ##{@id}"
   end
@@ -101,14 +107,13 @@ class Tag
   def to_key; id ? [id] : nil end
   def save; @id = 1; @post_id = 1 end
   def persisted?; @id.present? end
-  def to_param; @id; end
+  def to_param; @id && @id.to_s; end
   def value
     @id.nil? ? "new #{self.class.name.downcase}" : "#{self.class.name.downcase} ##{@id}"
   end
 
   attr_accessor :relevances
   def relevances_attributes=(attributes); end
-
 end
 
 class CommentRelevance
@@ -121,7 +126,7 @@ class CommentRelevance
   def to_key; id ? [id] : nil end
   def save; @id = 1; @comment_id = 1 end
   def persisted?; @id.present? end
-  def to_param; @id; end
+  def to_param; @id && @id.to_s; end
   def value
     @id.nil? ? "new #{self.class.name.downcase}" : "#{self.class.name.downcase} ##{@id}"
   end
@@ -137,7 +142,7 @@ class TagRelevance
   def to_key; id ? [id] : nil end
   def save; @id = 1; @tag_id = 1 end
   def persisted?; @id.present? end
-  def to_param; @id; end
+  def to_param; @id && @id.to_s; end
   def value
     @id.nil? ? "new #{self.class.name.downcase}" : "#{self.class.name.downcase} ##{@id}"
   end
@@ -164,7 +169,7 @@ module Blog
     true
   end
 
-  class Post < Struct.new(:title, :id)
+  Post = Struct.new(:title, :id) do
     extend ActiveModel::Naming
     include ActiveModel::Conversion
 
@@ -184,14 +189,13 @@ class ArelLike
   end
 end
 
-class Car < Struct.new(:color)
-end
+Car = Struct.new(:color)
 
 class Plane
   attr_reader :to_key
 
   def model_name
-    OpenStruct.new param_key: 'airplane'
+    OpenStruct.new param_key: "airplane"
   end
 
   def save
diff --git a/actionview/test/template/active_model_helper_test.rb b/actionview/test/template/active_model_helper_test.rb
index 55d62cf692..36afed6dd6 100644
--- a/actionview/test/template/active_model_helper_test.rb
+++ b/actionview/test/template/active_model_helper_test.rb
@@ -1,10 +1,12 @@
-require 'abstract_unit'
+# frozen_string_literal: true
+
+require "abstract_unit"
 
 class ActiveModelHelperTest < ActionView::TestCase
   tests ActionView::Helpers::ActiveModelHelper
 
   silence_warnings do
-    class Post < Struct.new(:author_name, :body, :updated_at)
+    Post = Struct.new(:author_name, :body, :category, :published, :updated_at) do
       include ActiveModel::Conversion
       include ActiveModel::Validations
 
@@ -20,10 +22,14 @@ class ActiveModelHelperTest < ActionView::TestCase
     @post = Post.new
     @post.errors[:author_name] << "can't be empty"
     @post.errors[:body] << "foo"
+    @post.errors[:category] << "must exist"
+    @post.errors[:published] << "must be accepted"
     @post.errors[:updated_at] << "bar"
 
     @post.author_name = ""
     @post.body        = "Back to the hill and over it again!"
+    @post.category    = "rails"
+    @post.published   = false
     @post.updated_at  = Date.new(2004, 6, 15)
   end
 
@@ -50,28 +56,96 @@ class ActiveModelHelperTest < ActionView::TestCase
 
   def test_select_with_errors_and_blank_option
     expected_dom = %(<div class="field_with_errors"><select name="post[author_name]" id="post_author_name"><option value="">Choose one...</option>\n<option value="a">a</option>\n<option value="b">b</option></select></div>)
-    assert_dom_equal(expected_dom, select("post", "author_name", [:a, :b], :include_blank => 'Choose one...'))
-    assert_dom_equal(expected_dom, select("post", "author_name", [:a, :b], :prompt => 'Choose one...'))
+    assert_dom_equal(expected_dom, select("post", "author_name", [:a, :b], include_blank: "Choose one..."))
+    assert_dom_equal(expected_dom, select("post", "author_name", [:a, :b], prompt: "Choose one..."))
+  end
+
+  def test_select_grouped_options_with_errors
+    grouped_options = [
+      ["A", [["A1"], ["A2"]]],
+      ["B", [["B1"], ["B2"]]],
+    ]
+
+    assert_dom_equal(
+      %(<div class="field_with_errors"><select name="post[category]" id="post_category"><optgroup label="A"><option value="A1">A1</option>\n<option value="A2">A2</option></optgroup><optgroup label="B"><option value="B1">B1</option>\n<option value="B2">B2</option></optgroup></select></div>),
+      select("post", "category", grouped_options)
+    )
+  end
+
+  def test_collection_select_with_errors
+    assert_dom_equal(
+      %(<div class="field_with_errors"><select name="post[author_name]" id="post_author_name"><option value="a">a</option>\n<option value="b">b</option></select></div>),
+      collection_select("post", "author_name", [:a, :b], :to_s, :to_s)
+    )
   end
 
   def test_date_select_with_errors
     assert_dom_equal(
       %(<div class="field_with_errors"><select id="post_updated_at_1i" name="post[updated_at(1i)]">\n<option selected="selected" value="2004">2004</option>\n<option value="2005">2005</option>\n</select>\n<input id="post_updated_at_2i" name="post[updated_at(2i)]" type="hidden" value="6" />\n<input id="post_updated_at_3i" name="post[updated_at(3i)]" type="hidden" value="1" />\n</div>),
-      date_select("post", "updated_at", :discard_month => true, :discard_day => true, :start_year => 2004, :end_year => 2005)
+      date_select("post", "updated_at", discard_month: true, discard_day: true, start_year: 2004, end_year: 2005)
     )
   end
 
   def test_datetime_select_with_errors
     assert_dom_equal(
       %(<div class="field_with_errors"><input id="post_updated_at_1i" name="post[updated_at(1i)]" type="hidden" value="2004" />\n<input id="post_updated_at_2i" name="post[updated_at(2i)]" type="hidden" value="6" />\n<input id="post_updated_at_3i" name="post[updated_at(3i)]" type="hidden" value="1" />\n<select id="post_updated_at_4i" name="post[updated_at(4i)]">\n<option selected="selected" value="00">00</option>\n<option value="01">01</option>\n<option value="02">02</option>\n<option value="03">03</option>\n<option value="04">04</option>\n<option value="05">05</option>\n<option value="06">06</option>\n<option value="07">07</option>\n<option value="08">08</option>\n<option value="09">09</option>\n<option value="10">10</option>\n<option value="11">11</option>\n<option value="12">12</option>\n<option value="13">13</option>\n<option value="14">14</option>\n<option value="15">15</option>\n<option value="16">16</option>\n<option value="17">17</option>\n<option value="18">18</option>\n<option value="19">19</option>\n<option value="20">20</option>\n<option value="21">21</option>\n<option value="22">22</option>\n<option value="23">23</option>\n</select>\n : <select id="post_updated_at_5i" name="post[updated_at(5i)]">\n<option selected="selected" value="00">00</option>\n</select>\n</div>),
-      datetime_select("post", "updated_at", :discard_year => true, :discard_month => true, :discard_day => true, :minute_step => 60)
+      datetime_select("post", "updated_at", discard_year: true, discard_month: true, discard_day: true, minute_step: 60)
     )
   end
 
   def test_time_select_with_errors
     assert_dom_equal(
       %(<div class="field_with_errors"><input id="post_updated_at_1i" name="post[updated_at(1i)]" type="hidden" value="2004" />\n<input id="post_updated_at_2i" name="post[updated_at(2i)]" type="hidden" value="6" />\n<input id="post_updated_at_3i" name="post[updated_at(3i)]" type="hidden" value="15" />\n<select id="post_updated_at_4i" name="post[updated_at(4i)]">\n<option selected="selected" value="00">00</option>\n<option value="01">01</option>\n<option value="02">02</option>\n<option value="03">03</option>\n<option value="04">04</option>\n<option value="05">05</option>\n<option value="06">06</option>\n<option value="07">07</option>\n<option value="08">08</option>\n<option value="09">09</option>\n<option value="10">10</option>\n<option value="11">11</option>\n<option value="12">12</option>\n<option value="13">13</option>\n<option value="14">14</option>\n<option value="15">15</option>\n<option value="16">16</option>\n<option value="17">17</option>\n<option value="18">18</option>\n<option value="19">19</option>\n<option value="20">20</option>\n<option value="21">21</option>\n<option value="22">22</option>\n<option value="23">23</option>\n</select>\n : <select id="post_updated_at_5i" name="post[updated_at(5i)]">\n<option selected="selected" value="00">00</option>\n</select>\n</div>),
-      time_select("post", "updated_at", :minute_step => 60)
+      time_select("post", "updated_at", minute_step: 60)
+    )
+  end
+
+  def test_label_with_errors
+    assert_dom_equal(
+      %(<div class="field_with_errors"><label for="post_body">Body</label></div>),
+      label("post", "body")
+    )
+  end
+
+  def test_check_box_with_errors
+    assert_dom_equal(
+      %(<input name="post[published]" type="hidden" value="0" /><div class="field_with_errors"><input type="checkbox" value="1" name="post[published]" id="post_published" /></div>),
+      check_box("post", "published")
+    )
+  end
+
+  def test_check_boxes_with_errors
+    assert_dom_equal(
+      %(<input name="post[published]" type="hidden" value="0" /><div class="field_with_errors"><input type="checkbox" value="1" name="post[published]" id="post_published" /></div><input name="post[published]" type="hidden" value="0" /><div class="field_with_errors"><input type="checkbox" value="1" name="post[published]" id="post_published" /></div>),
+      check_box("post", "published") + check_box("post", "published")
+    )
+  end
+
+  def test_radio_button_with_errors
+    assert_dom_equal(
+      %(<div class="field_with_errors"><input type="radio" value="rails" checked="checked" name="post[category]" id="post_category_rails" /></div>),
+      radio_button("post", "category", "rails")
+    )
+  end
+
+  def test_radio_buttons_with_errors
+    assert_dom_equal(
+      %(<div class="field_with_errors"><input type="radio" value="rails" checked="checked" name="post[category]" id="post_category_rails" /></div><div class="field_with_errors"><input type="radio" value="java" name="post[category]" id="post_category_java" /></div>),
+      radio_button("post", "category", "rails") + radio_button("post", "category", "java")
+    )
+  end
+
+  def test_collection_check_boxes_with_errors
+    assert_dom_equal(
+      %(<input type="hidden" name="post[category][]" value="" /><div class="field_with_errors"><input type="checkbox" value="ruby" name="post[category][]" id="post_category_ruby" /></div><label for="post_category_ruby">ruby</label><div class="field_with_errors"><input type="checkbox" value="java" name="post[category][]" id="post_category_java" /></div><label for="post_category_java">java</label>),
+      collection_check_boxes("post", "category", [:ruby, :java], :to_s, :to_s)
+    )
+  end
+
+  def test_collection_radio_buttons_with_errors
+    assert_dom_equal(
+      %(<input type="hidden" name="post[category]" value="" /><div class="field_with_errors"><input type="radio" value="ruby" name="post[category]" id="post_category_ruby" /></div><label for="post_category_ruby">ruby</label><div class="field_with_errors"><input type="radio" value="java" name="post[category]" id="post_category_java" /></div><label for="post_category_java">java</label>),
+      collection_radio_buttons("post", "category", [:ruby, :java], :to_s, :to_s)
     )
   end
 
@@ -95,5 +169,4 @@ class ActiveModelHelperTest < ActionView::TestCase
   ensure
     ActionView::Base.field_error_proc = old_proc if old_proc
   end
-
 end
diff --git a/actionview/test/template/asset_tag_helper_test.rb b/actionview/test/template/asset_tag_helper_test.rb
index 8bfd19eb26..284dacf2d4 100644
--- a/actionview/test/template/asset_tag_helper_test.rb
+++ b/actionview/test/template/asset_tag_helper_test.rb
@@ -1,5 +1,7 @@
-require 'abstract_unit'
-require 'active_support/ordered_options'
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "active_support/ordered_options"
 
 class AssetTagHelperTest < ActionView::TestCase
   tests ActionView::Helpers::AssetTagHelper
@@ -13,10 +15,11 @@ class AssetTagHelperTest < ActionView::TestCase
 
     @request = Class.new do
       attr_accessor :script_name
-      def protocol() 'http://' end
+      def protocol() "http://" end
       def ssl?() false end
-      def host_with_port() 'localhost' end
-      def base_url() 'http://www.example.com' end
+      def host_with_port() "localhost" end
+      def base_url() "http://www.example.com" end
+      def send_early_hints(links) end
     end.new
 
     @controller.request = @request
@@ -53,6 +56,7 @@ class AssetTagHelperTest < ActionView::TestCase
     %(auto_discovery_link_tag) => %(<link href="http://www.example.com" rel="alternate" title="RSS" type="application/rss+xml" />),
     %(auto_discovery_link_tag(:rss)) => %(<link href="http://www.example.com" rel="alternate" title="RSS" type="application/rss+xml" />),
     %(auto_discovery_link_tag(:atom)) => %(<link href="http://www.example.com" rel="alternate" title="ATOM" type="application/atom+xml" />),
+    %(auto_discovery_link_tag(:json)) => %(<link href="http://www.example.com" rel="alternate" title="JSON" type="application/json" />),
     %(auto_discovery_link_tag(:rss, :action => "feed")) => %(<link href="http://www.example.com" rel="alternate" title="RSS" type="application/rss+xml" />),
     %(auto_discovery_link_tag(:rss, "http://localhost/feed")) => %(<link href="http://localhost/feed" rel="alternate" title="RSS" type="application/rss+xml" />),
     %(auto_discovery_link_tag(:rss, "//localhost/feed")) => %(<link href="//localhost/feed" rel="alternate" title="RSS" type="application/rss+xml" />),
@@ -180,23 +184,26 @@ class AssetTagHelperTest < ActionView::TestCase
   }
 
   ImageLinkToTag = {
-    %(image_tag("xml.png")) => %(<img alt="Xml" src="/images/xml.png" />),
+    %(image_tag("xml.png")) => %(<img src="/images/xml.png" />),
     %(image_tag("rss.gif", :alt => "rss syndication")) => %(<img alt="rss syndication" src="/images/rss.gif" />),
-    %(image_tag("gold.png", :size => "20")) => %(<img alt="Gold" height="20" src="/images/gold.png" width="20" />),
-    %(image_tag("gold.png", :size => 20)) => %(<img alt="Gold" height="20" src="/images/gold.png" width="20" />),
-    %(image_tag("gold.png", :size => "45x70")) => %(<img alt="Gold" height="70" src="/images/gold.png" width="45" />),
-    %(image_tag("gold.png", "size" => "45x70")) => %(<img alt="Gold" height="70" src="/images/gold.png" width="45" />),
-    %(image_tag("error.png", "size" => "45 x 70")) => %(<img alt="Error" src="/images/error.png" />),
-    %(image_tag("error.png", "size" => "x")) => %(<img alt="Error" src="/images/error.png" />),
-    %(image_tag("google.com.png")) => %(<img alt="Google.com" src="/images/google.com.png" />),
-    %(image_tag("slash..png")) => %(<img alt="Slash." src="/images/slash..png" />),
-    %(image_tag(".pdf.png")) => %(<img alt=".pdf" src="/images/.pdf.png" />),
-    %(image_tag("http://www.rubyonrails.com/images/rails.png")) => %(<img alt="Rails" src="http://www.rubyonrails.com/images/rails.png" />),
-    %(image_tag("//www.rubyonrails.com/images/rails.png")) => %(<img alt="Rails" src="//www.rubyonrails.com/images/rails.png" />),
+    %(image_tag("gold.png", :size => "20")) => %(<img height="20" src="/images/gold.png" width="20" />),
+    %(image_tag("gold.png", :size => 20)) => %(<img height="20" src="/images/gold.png" width="20" />),
+    %(image_tag("gold.png", :size => "45x70")) => %(<img height="70" src="/images/gold.png" width="45" />),
+    %(image_tag("gold.png", "size" => "45x70")) => %(<img height="70" src="/images/gold.png" width="45" />),
+    %(image_tag("error.png", "size" => "45 x 70")) => %(<img src="/images/error.png" />),
+    %(image_tag("error.png", "size" => "x")) => %(<img src="/images/error.png" />),
+    %(image_tag("google.com.png")) => %(<img src="/images/google.com.png" />),
+    %(image_tag("slash..png")) => %(<img src="/images/slash..png" />),
+    %(image_tag(".pdf.png")) => %(<img src="/images/.pdf.png" />),
+    %(image_tag("http://www.rubyonrails.com/images/rails.png")) => %(<img src="http://www.rubyonrails.com/images/rails.png" />),
+    %(image_tag("//www.rubyonrails.com/images/rails.png")) => %(<img src="//www.rubyonrails.com/images/rails.png" />),
     %(image_tag("mouse.png", :alt => nil)) => %(<img src="/images/mouse.png" />),
     %(image_tag("data:image/gif;base64,R0lGODlhAQABAID/AMDAwAAAACH5BAEAAAAALAAAAAABAAEAAAICRAEAOw==", :alt => nil)) => %(<img src="data:image/gif;base64,R0lGODlhAQABAID/AMDAwAAAACH5BAEAAAAALAAAAAABAAEAAAICRAEAOw==" />),
     %(image_tag("")) => %(<img src="" />),
-    %(image_tag("gold.png", data: { title: 'Rails Application' })) => %(<img data-title="Rails Application" src="/images/gold.png" alt="Gold" />)
+    %(image_tag("gold.png", data: { title: 'Rails Application' })) => %(<img data-title="Rails Application" src="/images/gold.png" />),
+    %(image_tag("rss.gif", srcset: "/assets/pic_640.jpg 640w, /assets/pic_1024.jpg 1024w")) => %(<img srcset="/assets/pic_640.jpg 640w, /assets/pic_1024.jpg 1024w" src="/images/rss.gif" />),
+    %(image_tag("rss.gif", srcset: { "pic_640.jpg" => "640w", "pic_1024.jpg" => "1024w" })) => %(<img srcset="/images/pic_640.jpg 640w, /images/pic_1024.jpg 1024w" src="/images/rss.gif" />),
+    %(image_tag("rss.gif", srcset: [["pic_640.jpg", "640w"], ["pic_1024.jpg", "1024w"]])) => %(<img srcset="/images/pic_640.jpg 640w, /images/pic_1024.jpg 1024w" src="/images/rss.gif" />)
   }
 
   FaviconLinkToTag = {
@@ -207,6 +214,17 @@ class AssetTagHelperTest < ActionView::TestCase
     %(favicon_link_tag 'mb-icon.png', :rel => 'apple-touch-icon', :type => 'image/png') => %(<link href="/images/mb-icon.png" rel="apple-touch-icon" type="image/png" />)
   }
 
+  PreloadLinkToTag = {
+    %(preload_link_tag '/styles/custom_theme.css') => %(<link rel="preload" href="/styles/custom_theme.css" as="style" type="text/css" />),
+    %(preload_link_tag '/videos/video.webm') => %(<link rel="preload" href="/videos/video.webm" as="video" type="video/webm" />),
+    %(preload_link_tag '/posts.json', as: 'fetch') => %(<link rel="preload" href="/posts.json" as="fetch" type="application/json" />),
+    %(preload_link_tag '/users', as: 'fetch', type: 'application/json') => %(<link rel="preload" href="/users" as="fetch" type="application/json" />),
+    %(preload_link_tag '//example.com/map?callback=initMap', as: 'fetch', type: 'application/javascript') => %(<link rel="preload" href="//example.com/map?callback=initMap" as="fetch" type="application/javascript" />),
+    %(preload_link_tag '//example.com/font.woff2') => %(<link rel="preload" href="//example.com/font.woff2" as="font" type="font/woff2" crossorigin="anonymous"/>),
+    %(preload_link_tag '//example.com/font.woff2', crossorigin: 'use-credentials') => %(<link rel="preload" href="//example.com/font.woff2" as="font" type="font/woff2" crossorigin="use-credentials" />),
+    %(preload_link_tag '/media/audio.ogg', nopush: true) => %(<link rel="preload" href="/media/audio.ogg" as="audio" type="audio/ogg" />)
+  }
+
   VideoPathToTag = {
     %(video_path("xml"))          => %(/videos/xml),
     %(video_path("xml.ogg"))      => %(/videos/xml.ogg),
@@ -238,7 +256,7 @@ class AssetTagHelperTest < ActionView::TestCase
   VideoLinkToTag = {
     %(video_tag("xml.ogg")) => %(<video src="/videos/xml.ogg"></video>),
     %(video_tag("rss.m4v", :autoplay => true, :controls => true)) => %(<video autoplay="autoplay" controls="controls" src="/videos/rss.m4v"></video>),
-    %(video_tag("rss.m4v", :autobuffer => true)) => %(<video autobuffer="autobuffer" src="/videos/rss.m4v"></video>),
+    %(video_tag("rss.m4v", :preload => 'none')) => %(<video preload="none" src="/videos/rss.m4v"></video>),
     %(video_tag("gold.m4v", :size => "160x120")) => %(<video height="120" src="/videos/gold.m4v" width="160"></video>),
     %(video_tag("gold.m4v", "size" => "320x240")) => %(<video height="240" src="/videos/gold.m4v" width="320"></video>),
     %(video_tag("trailer.ogg", :poster => "screenshot.png")) => %(<video poster="/images/screenshot.png" src="/videos/trailer.ogg"></video>),
@@ -288,7 +306,7 @@ class AssetTagHelperTest < ActionView::TestCase
     %(audio_tag("//media.rubyonrails.org/audio/rails_blog_2.mov")) => %(<audio src="//media.rubyonrails.org/audio/rails_blog_2.mov"></audio>),
     %(audio_tag("audio.mp3", "audio.ogg")) => %(<audio><source src="/audios/audio.mp3" /><source src="/audios/audio.ogg" /></audio>),
     %(audio_tag(["audio.mp3", "audio.ogg"])) => %(<audio><source src="/audios/audio.mp3" /><source src="/audios/audio.ogg" /></audio>),
-    %(audio_tag(["audio.mp3", "audio.ogg"], :autobuffer => true, :controls => true)) => %(<audio autobuffer="autobuffer" controls="controls"><source src="/audios/audio.mp3" /><source src="/audios/audio.ogg" /></audio>)
+    %(audio_tag(["audio.mp3", "audio.ogg"], :preload => 'none', :controls => true)) => %(<audio preload="none" controls="controls"><source src="/audios/audio.mp3" /><source src="/audios/audio.ogg" /></audio>)
   }
 
   FontPathToTag = {
@@ -299,6 +317,24 @@ class AssetTagHelperTest < ActionView::TestCase
     %(font_path("font.ttf?123")) => %(/fonts/font.ttf?123)
   }
 
+  FontUrlToTag = {
+    %(font_url("font.eot")) => %(http://www.example.com/fonts/font.eot),
+    %(font_url("font.eot#iefix")) => %(http://www.example.com/fonts/font.eot#iefix),
+    %(font_url("font.woff")) => %(http://www.example.com/fonts/font.woff),
+    %(font_url("font.ttf")) => %(http://www.example.com/fonts/font.ttf),
+    %(font_url("font.ttf?123")) => %(http://www.example.com/fonts/font.ttf?123),
+    %(font_url("font.ttf", host: "http://assets.example.com")) => %(http://assets.example.com/fonts/font.ttf)
+  }
+
+  UrlToFontToTag = {
+    %(url_to_font("font.eot")) => %(http://www.example.com/fonts/font.eot),
+    %(url_to_font("font.eot#iefix")) => %(http://www.example.com/fonts/font.eot#iefix),
+    %(url_to_font("font.woff")) => %(http://www.example.com/fonts/font.woff),
+    %(url_to_font("font.ttf")) => %(http://www.example.com/fonts/font.ttf),
+    %(url_to_font("font.ttf?123")) => %(http://www.example.com/fonts/font.ttf?123),
+    %(url_to_font("font.ttf", host: "http://assets.example.com")) => %(http://assets.example.com/fonts/font.ttf)
+  }
+
   def test_autodiscovery_link_tag_with_unknown_type_but_not_pass_type_option_key
     assert_raise(ArgumentError) do
       auto_discovery_link_tag(:xml)
@@ -306,7 +342,7 @@ class AssetTagHelperTest < ActionView::TestCase
   end
 
   def test_autodiscovery_link_tag_with_unknown_type
-    result = auto_discovery_link_tag(:xml, '/feed.xml', :type => 'application/xml')
+    result = auto_discovery_link_tag(:xml, "/feed.xml", type: "application/xml")
     expected = %(<link href="/feed.xml" rel="alternate" title="XML" type="application/xml" />)
     assert_dom_equal expected, result
   end
@@ -322,18 +358,18 @@ class AssetTagHelperTest < ActionView::TestCase
 
   def test_asset_path_tag_to_not_create_duplicate_slashes
     @controller.config.asset_host = "host/"
-    assert_dom_equal('http://host/foo', asset_path("foo"))
+    assert_dom_equal("http://host/foo", asset_path("foo"))
 
-    @controller.config.relative_url_root = '/some/root/'
-    assert_dom_equal('http://host/some/root/foo', asset_path("foo"))
+    @controller.config.relative_url_root = "/some/root/"
+    assert_dom_equal("http://host/some/root/foo", asset_path("foo"))
   end
 
   def test_compute_asset_public_path
     assert_equal "/robots.txt", compute_asset_path("robots.txt")
     assert_equal "/robots.txt", compute_asset_path("/robots.txt")
-    assert_equal "/javascripts/foo.js", compute_asset_path("foo.js", :type => :javascript)
-    assert_equal "/javascripts/foo.js", compute_asset_path("/foo.js", :type => :javascript)
-    assert_equal "/stylesheets/foo.css", compute_asset_path("foo.css", :type => :stylesheet)
+    assert_equal "/javascripts/foo.js", compute_asset_path("foo.js", type: :javascript)
+    assert_equal "/javascripts/foo.js", compute_asset_path("/foo.js", type: :javascript)
+    assert_equal "/stylesheets/foo.css", compute_asset_path("foo.css", type: :stylesheet)
   end
 
   def test_auto_discovery_link_tag
@@ -362,11 +398,11 @@ class AssetTagHelperTest < ActionView::TestCase
 
   def test_javascript_include_tag_with_missing_source
     assert_nothing_raised {
-      javascript_include_tag('missing_security_guard')
+      javascript_include_tag("missing_security_guard")
     }
 
     assert_nothing_raised {
-      javascript_include_tag('http://example.com/css/missing_security_guard')
+      javascript_include_tag("http://example.com/css/missing_security_guard")
     }
   end
 
@@ -376,13 +412,13 @@ class AssetTagHelperTest < ActionView::TestCase
 
   def test_javascript_include_tag_relative_protocol
     @controller.config.asset_host = "assets.example.com"
-    assert_dom_equal %(<script src="//assets.example.com/javascripts/prototype.js"></script>), javascript_include_tag('prototype', protocol: :relative)
+    assert_dom_equal %(<script src="//assets.example.com/javascripts/prototype.js"></script>), javascript_include_tag("prototype", protocol: :relative)
   end
 
   def test_javascript_include_tag_default_protocol
     @controller.config.asset_host = "assets.example.com"
     @controller.config.default_asset_host_protocol = :relative
-    assert_dom_equal %(<script src="//assets.example.com/javascripts/prototype.js"></script>), javascript_include_tag('prototype')
+    assert_dom_equal %(<script src="//assets.example.com/javascripts/prototype.js"></script>), javascript_include_tag("prototype")
   end
 
   def test_stylesheet_path
@@ -407,36 +443,49 @@ class AssetTagHelperTest < ActionView::TestCase
 
   def test_stylesheet_link_tag_with_missing_source
     assert_nothing_raised {
-      stylesheet_link_tag('missing_security_guard')
+      stylesheet_link_tag("missing_security_guard")
     }
 
     assert_nothing_raised {
-      stylesheet_link_tag('http://example.com/css/missing_security_guard')
+      stylesheet_link_tag("http://example.com/css/missing_security_guard")
     }
   end
 
+  def test_stylesheet_link_tag_without_request
+    @request = nil
+    assert_dom_equal(
+      %(<link rel="stylesheet" media="screen" href="/stylesheets/foo.css" />),
+      stylesheet_link_tag("foo.css")
+    )
+  end
+
   def test_stylesheet_link_tag_is_html_safe
-    assert stylesheet_link_tag('dir/file').html_safe?
-    assert stylesheet_link_tag('dir/other/file', 'dir/file2').html_safe?
+    assert stylesheet_link_tag("dir/file").html_safe?
+    assert stylesheet_link_tag("dir/other/file", "dir/file2").html_safe?
   end
 
   def test_stylesheet_link_tag_escapes_options
-    assert_dom_equal %(<link href="/file.css" media="&lt;script&gt;" rel="stylesheet" />), stylesheet_link_tag('/file', :media => '<script>')
+    assert_dom_equal %(<link href="/file.css" media="&lt;script&gt;" rel="stylesheet" />), stylesheet_link_tag("/file", media: "<script>")
   end
 
   def test_stylesheet_link_tag_should_not_output_the_same_asset_twice
-    assert_dom_equal %(<link href="/stylesheets/wellington.css" media="screen" rel="stylesheet" />\n<link href="/stylesheets/amsterdam.css" media="screen" rel="stylesheet" />), stylesheet_link_tag('wellington', 'wellington', 'amsterdam')
+    assert_dom_equal %(<link href="/stylesheets/wellington.css" media="screen" rel="stylesheet" />\n<link href="/stylesheets/amsterdam.css" media="screen" rel="stylesheet" />), stylesheet_link_tag("wellington", "wellington", "amsterdam")
   end
 
   def test_stylesheet_link_tag_with_relative_protocol
     @controller.config.asset_host = "assets.example.com"
-    assert_dom_equal %(<link href="//assets.example.com/stylesheets/wellington.css" media="screen" rel="stylesheet" />), stylesheet_link_tag('wellington', protocol: :relative)
+    assert_dom_equal %(<link href="//assets.example.com/stylesheets/wellington.css" media="screen" rel="stylesheet" />), stylesheet_link_tag("wellington", protocol: :relative)
   end
 
   def test_stylesheet_link_tag_with_default_protocol
     @controller.config.asset_host = "assets.example.com"
     @controller.config.default_asset_host_protocol = :relative
-    assert_dom_equal %(<link href="//assets.example.com/stylesheets/wellington.css" media="screen" rel="stylesheet" />), stylesheet_link_tag('wellington')
+    assert_dom_equal %(<link href="//assets.example.com/stylesheets/wellington.css" media="screen" rel="stylesheet" />), stylesheet_link_tag("wellington")
+  end
+
+  def test_javascript_include_tag_without_request
+    @request = nil
+    assert_dom_equal %(<script src="/javascripts/foo.js"></script>), javascript_include_tag("foo.js")
   end
 
   def test_image_path
@@ -456,12 +505,22 @@ class AssetTagHelperTest < ActionView::TestCase
   end
 
   def test_image_alt
-    [nil, '/', '/foo/bar/', 'foo/bar/'].each do |prefix|
-      assert_equal 'Rails', image_alt("#{prefix}rails.png")
-      assert_equal 'Rails', image_alt("#{prefix}rails-9c0a079bdd7701d7e729bd956823d153.png")
-      assert_equal 'Rails', image_alt("#{prefix}rails-f56ef62bc41b040664e801a38f068082a75d506d9048307e8096737463503d0b.png")
-      assert_equal 'Long file name with hyphens', image_alt("#{prefix}long-file-name-with-hyphens.png")
-      assert_equal 'Long file name with underscores', image_alt("#{prefix}long_file_name_with_underscores.png")
+    [nil, "/", "/foo/bar/", "foo/bar/"].each do |prefix|
+      assert_deprecated do
+        assert_equal "Rails", image_alt("#{prefix}rails.png")
+      end
+      assert_deprecated do
+        assert_equal "Rails", image_alt("#{prefix}rails-9c0a079bdd7701d7e729bd956823d153.png")
+      end
+      assert_deprecated do
+        assert_equal "Rails", image_alt("#{prefix}rails-f56ef62bc41b040664e801a38f068082a75d506d9048307e8096737463503d0b.png")
+      end
+      assert_deprecated do
+        assert_equal "Long file name with hyphens", image_alt("#{prefix}long-file-name-with-hyphens.png")
+      end
+      assert_deprecated do
+        assert_equal "Long file name with underscores", image_alt("#{prefix}long_file_name_with_underscores.png")
+      end
     end
   end
 
@@ -470,14 +529,14 @@ class AssetTagHelperTest < ActionView::TestCase
   end
 
   def test_image_tag_does_not_modify_options
-    options = {:size => '16x10'}
-    image_tag('icon', options)
-    assert_equal({:size => '16x10'}, options)
+    options = { size: "16x10" }
+    image_tag("icon", options)
+    assert_equal({ size: "16x10" }, options)
   end
 
   def test_image_tag_raises_an_error_for_competing_size_arguments
     exception = assert_raise(ArgumentError) do
-      image_tag("gold.png", :height => "100", :width => "200", :size => "45x70")
+      image_tag("gold.png", height: "100", width: "200", size: "45x70")
     end
 
     assert_equal("Cannot pass a :size option with a :height or :width option", exception.message)
@@ -487,6 +546,10 @@ class AssetTagHelperTest < ActionView::TestCase
     FaviconLinkToTag.each { |method, tag| assert_dom_equal(tag, eval(method)) }
   end
 
+  def test_preload_link_tag
+    PreloadLinkToTag.each { |method, tag| assert_dom_equal(tag, eval(method)) }
+  end
+
   def test_video_path
     VideoPathToTag.each { |method, tag| assert_dom_equal(tag, eval(method)) }
   end
@@ -531,12 +594,20 @@ class AssetTagHelperTest < ActionView::TestCase
     FontPathToTag.each { |method, tag| assert_dom_equal(tag, eval(method)) }
   end
 
+  def test_font_url
+    FontUrlToTag.each { |method, tag| assert_dom_equal(tag, eval(method)) }
+  end
+
+  def test_url_to_font_alias_for_font_url
+    UrlToFontToTag.each { |method, tag| assert_dom_equal(tag, eval(method)) }
+  end
+
   def test_video_audio_tag_does_not_modify_options
-    options = {:autoplay => true}
-    video_tag('video', options)
-    assert_equal({:autoplay => true}, options)
-    audio_tag('audio', options)
-    assert_equal({:autoplay => true}, options)
+    options = { autoplay: true }
+    video_tag("video", options)
+    assert_equal({ autoplay: true }, options)
+    audio_tag("audio", options)
+    assert_equal({ autoplay: true }, options)
   end
 
   def test_image_tag_interpreting_email_cid_correctly
@@ -545,11 +616,11 @@ class AssetTagHelperTest < ActionView::TestCase
   end
 
   def test_image_tag_interpreting_email_adding_optional_alt_tag
-    assert_equal '<img alt="Image" src="cid:thi%25%25sis@acontentid" />', image_tag("cid:thi%25%25sis@acontentid", :alt => "Image")
+    assert_equal '<img alt="Image" src="cid:thi%25%25sis@acontentid" />', image_tag("cid:thi%25%25sis@acontentid", alt: "Image")
   end
 
   def test_should_not_modify_source_string
-    source = '/images/rails.png'
+    source = "/images/rails.png"
     copy = source.dup
     image_tag(source)
     assert_equal copy, source
@@ -557,13 +628,10 @@ class AssetTagHelperTest < ActionView::TestCase
 
   class PlaceholderImage
     def blank?; true; end
-    def to_s; 'no-image-yet.png'; end
-  end
-  def test_image_tag_with_blank_placeholder
-    assert_equal '<img alt="" src="/images/no-image-yet.png" />', image_tag(PlaceholderImage.new, alt: "")
+    def to_s; "no-image-yet.png"; end
   end
   def test_image_path_with_blank_placeholder
-    assert_equal '/images/no-image-yet.png', image_path(PlaceholderImage.new)
+    assert_equal "/images/no-image-yet.png", image_path(PlaceholderImage.new)
   end
 
   def test_image_path_with_asset_host_proc_returning_nil
@@ -614,7 +682,9 @@ class AssetTagHelperNonVhostTest < ActionView::TestCase
     @controller = BasicController.new
     @controller.config.relative_url_root = "/collaboration/hieraki"
 
-    @request = Struct.new(:protocol, :base_url).new("gopher://", "gopher://www.example.com")
+    @request = Struct.new(:protocol, :base_url) do
+      def send_early_hints(links); end
+    end.new("gopher://", "gopher://www.example.com")
     @controller.request = @request
   end
 
@@ -630,15 +700,15 @@ class AssetTagHelperNonVhostTest < ActionView::TestCase
   end
 
   def test_should_return_nothing_if_asset_host_isnt_configured
-    assert_equal nil, compute_asset_host("foo")
+    assert_nil compute_asset_host("foo")
   end
 
   def test_should_current_request_host_is_always_returned_for_request
-    assert_equal "gopher://www.example.com", compute_asset_host("foo", :protocol => :request)
+    assert_equal "gopher://www.example.com", compute_asset_host("foo", protocol: :request)
   end
 
   def test_should_return_custom_host_if_passed_in_options
-    assert_equal "http://custom.example.com", compute_asset_host("foo", :host => "http://custom.example.com")
+    assert_equal "http://custom.example.com", compute_asset_host("foo", host: "http://custom.example.com")
   end
 
   def test_should_ignore_relative_root_path_on_complete_url
@@ -652,12 +722,12 @@ class AssetTagHelperNonVhostTest < ActionView::TestCase
 
   def test_should_return_relative_asset_host
     @controller.config.asset_host = "assets.example.com"
-    assert_equal "//assets.example.com", compute_asset_host("foo", :protocol => :relative)
+    assert_equal "//assets.example.com", compute_asset_host("foo", protocol: :relative)
   end
 
   def test_should_return_custom_protocol_asset_host
     @controller.config.asset_host = "assets.example.com"
-    assert_equal "ftp://assets.example.com", compute_asset_host("foo", :protocol => "ftp")
+    assert_equal "ftp://assets.example.com", compute_asset_host("foo", protocol: "ftp")
   end
 
   def test_should_compute_proper_path_with_asset_host
@@ -708,26 +778,26 @@ class AssetTagHelperNonVhostTest < ActionView::TestCase
   end
 
   def test_should_wildcard_asset_host
-    @controller.config.asset_host = 'http://a%d.example.com'
-    assert_match(%r(http://a[0123].example.com), compute_asset_host("foo"))
+    @controller.config.asset_host = "http://a%d.example.com"
+    assert_match(%r(http://a[0123]\.example\.com), compute_asset_host("foo"))
   end
 
   def test_should_wildcard_asset_host_between_zero_and_four
-    @controller.config.asset_host = 'http://a%d.example.com'
-    assert_match(%r(http://a[0123].example.com/collaboration/hieraki/images/xml.png), image_path('xml.png'))
-    assert_match(%r(http://a[0123].example.com/collaboration/hieraki/images/xml.png), image_url('xml.png'))
+    @controller.config.asset_host = "http://a%d.example.com"
+    assert_match(%r(http://a[0123]\.example\.com/collaboration/hieraki/images/xml\.png), image_path("xml.png"))
+    assert_match(%r(http://a[0123]\.example\.com/collaboration/hieraki/images/xml\.png), image_url("xml.png"))
   end
 
   def test_asset_host_without_protocol_should_be_protocol_relative
-    @controller.config.asset_host = 'a.example.com'
-    assert_equal 'gopher://a.example.com/collaboration/hieraki/images/xml.png', image_path('xml.png')
-    assert_equal 'gopher://a.example.com/collaboration/hieraki/images/xml.png', image_url('xml.png')
+    @controller.config.asset_host = "a.example.com"
+    assert_equal "gopher://a.example.com/collaboration/hieraki/images/xml.png", image_path("xml.png")
+    assert_equal "gopher://a.example.com/collaboration/hieraki/images/xml.png", image_url("xml.png")
   end
 
   def test_asset_host_without_protocol_should_be_protocol_relative_even_if_path_present
-    @controller.config.asset_host = 'a.example.com/files/go/here'
-    assert_equal 'gopher://a.example.com/files/go/here/collaboration/hieraki/images/xml.png', image_path('xml.png')
-    assert_equal 'gopher://a.example.com/files/go/here/collaboration/hieraki/images/xml.png', image_url('xml.png')
+    @controller.config.asset_host = "a.example.com/files/go/here"
+    assert_equal "gopher://a.example.com/files/go/here/collaboration/hieraki/images/xml.png", image_path("xml.png")
+    assert_equal "gopher://a.example.com/files/go/here/collaboration/hieraki/images/xml.png", image_url("xml.png")
   end
 
   def test_assert_css_and_js_of_the_same_name_return_correct_extension
@@ -736,6 +806,23 @@ class AssetTagHelperNonVhostTest < ActionView::TestCase
   end
 end
 
+class AssetTagHelperWithoutRequestTest < ActionView::TestCase
+  tests ActionView::Helpers::AssetTagHelper
+
+  undef :request
+
+  def test_stylesheet_link_tag_without_request
+    assert_dom_equal(
+      %(<link rel="stylesheet" media="screen" href="/stylesheets/foo.css" />),
+      stylesheet_link_tag("foo.css")
+    )
+  end
+
+  def test_javascript_include_tag_without_request
+    assert_dom_equal %(<script src="/javascripts/foo.js"></script>), javascript_include_tag("foo.js")
+  end
+end
+
 class AssetUrlHelperControllerTest < ActionView::TestCase
   tests ActionView::Helpers::AssetUrlHelper
 
@@ -747,10 +834,10 @@ class AssetUrlHelperControllerTest < ActionView::TestCase
 
     @request = Class.new do
       attr_accessor :script_name
-      def protocol() 'http://' end
+      def protocol() "http://" end
       def ssl?() false end
-      def host_with_port() 'www.example.com' end
-      def base_url() 'http://www.example.com' end
+      def host_with_port() "www.example.com" end
+      def base_url() "http://www.example.com" end
     end.new
 
     @controller.request = @request
@@ -813,6 +900,6 @@ class AssetUrlHelperEmptyModuleTest < ActionView::TestCase
     end
 
     assert @module.config.asset_host
-    assert_equal "http://custom.example.com/foo", @module.asset_url("foo", :host => "http://custom.example.com")
+    assert_equal "http://custom.example.com/foo", @module.asset_url("foo", host: "http://custom.example.com")
   end
 end
diff --git a/actionview/test/template/atom_feed_helper_test.rb b/actionview/test/template/atom_feed_helper_test.rb
index 591cd71404..1be20dcaae 100644
--- a/actionview/test/template/atom_feed_helper_test.rb
+++ b/actionview/test/template/atom_feed_helper_test.rb
@@ -1,6 +1,8 @@
-require 'abstract_unit'
+# frozen_string_literal: true
 
-class Scroll < Struct.new(:id, :to_param, :title, :body, :updated_at, :created_at)
+require "abstract_unit"
+
+Scroll = Struct.new(:id, :to_param, :title, :body, :updated_at, :created_at) do
   extend ActiveModel::Naming
   include ActiveModel::Conversion
 
@@ -28,7 +30,7 @@ class ScrollsController < ActionController::Base
           end
         end
     EOT
-    FEEDS["entry_options"] = <<-EOT
+  FEEDS["entry_options"] = <<-EOT
         atom_feed do |feed|
           feed.title("My great blog!")
           feed.updated(@scrolls.first.created_at)
@@ -45,7 +47,7 @@ class ScrollsController < ActionController::Base
           end
         end
     EOT
-    FEEDS["entry_type_options"] = <<-EOT
+  FEEDS["entry_type_options"] = <<-EOT
         atom_feed(:schema_date => '2008') do |feed|
           feed.title("My great blog!")
           feed.updated(@scrolls.first.created_at)
@@ -62,7 +64,7 @@ class ScrollsController < ActionController::Base
           end
         end
     EOT
-    FEEDS["entry_url_false_option"] = <<-EOT
+  FEEDS["entry_url_false_option"] = <<-EOT
         atom_feed do |feed|
           feed.title("My great blog!")
           feed.updated(@scrolls.first.created_at)
@@ -79,7 +81,7 @@ class ScrollsController < ActionController::Base
           end
         end
     EOT
-    FEEDS["xml_block"] = <<-EOT
+  FEEDS["xml_block"] = <<-EOT
         atom_feed do |feed|
           feed.title("My great blog!")
           feed.updated(@scrolls.first.created_at)
@@ -96,7 +98,7 @@ class ScrollsController < ActionController::Base
           end
         end
     EOT
-    FEEDS["feed_with_atomPub_namespace"] = <<-EOT
+  FEEDS["feed_with_atomPub_namespace"] = <<-EOT
         atom_feed({'xmlns:app' => 'http://www.w3.org/2007/app',
                  'xmlns:openSearch' => 'http://a9.com/-/spec/opensearch/1.1/'}) do |feed|
           feed.title("My great blog!")
@@ -115,7 +117,7 @@ class ScrollsController < ActionController::Base
           end
         end
     EOT
-    FEEDS["feed_with_overridden_ids"] = <<-EOT
+  FEEDS["feed_with_overridden_ids"] = <<-EOT
         atom_feed({:id => 'tag:test.rubyonrails.org,2008:test/'}) do |feed|
           feed.title("My great blog!")
           feed.updated(@scrolls.first.created_at)
@@ -169,7 +171,7 @@ class ScrollsController < ActionController::Base
           end
         end
     EOT
-    FEEDS["feed_with_xhtml_content"] = <<-'EOT'
+  FEEDS["feed_with_xhtml_content"] = <<-'EOT'
         atom_feed do |feed|
           feed.title("My great blog!")
           feed.updated(@scrolls.first.created_at)
@@ -191,10 +193,10 @@ class ScrollsController < ActionController::Base
           end
         end
     EOT
-    FEEDS["provide_builder"] = <<-'EOT'
+  FEEDS["provide_builder"] = <<-'EOT'
           # we pass in the new_xml to the helper so it doesn't
           # call anything on the original builder
-          new_xml = Builder::XmlMarkup.new(:target=>'')
+          new_xml = Builder::XmlMarkup.new(:target=>''.dup)
           atom_feed(:xml => new_xml) do |feed|
             feed.title("My great blog!")
             feed.updated(@scrolls.first.created_at)
@@ -217,7 +219,7 @@ class ScrollsController < ActionController::Base
       Scroll.new(2, "2", "Hello Two", "Something Boring", Time.utc(2007, 12, 12, 15)),
     ]
 
-    render :inline => FEEDS[params[:id]], :type => :builder
+    render inline: FEEDS[params[:id]], type: :builder
   end
 end
 
@@ -278,22 +280,22 @@ class AtomFeedTest < ActionController::TestCase
   def test_feed_id_should_be_a_valid_tag
     with_restful_routing(:scrolls) do
       get :index, params: { id: "defaults" }
-      assert_select "id", :text => "tag:www.nextangle.com,2008:/scrolls?id=defaults"
+      assert_select "id", text: "tag:www.nextangle.com,2008:/scrolls?id=defaults"
     end
   end
 
   def test_entry_id_should_be_a_valid_tag
     with_restful_routing(:scrolls) do
       get :index, params: { id: "defaults" }
-      assert_select "entry id", :text => "tag:www.nextangle.com,2008:Scroll/1"
-      assert_select "entry id", :text => "tag:www.nextangle.com,2008:Scroll/2"
+      assert_select "entry id", text: "tag:www.nextangle.com,2008:Scroll/1"
+      assert_select "entry id", text: "tag:www.nextangle.com,2008:Scroll/2"
     end
   end
 
   def test_feed_should_allow_nested_xml_blocks
     with_restful_routing(:scrolls) do
       get :index, params: { id: "xml_block" }
-      assert_select "author name", :text => "DHH"
+      assert_select "author name", text: "DHH"
     end
   end
 
@@ -301,31 +303,31 @@ class AtomFeedTest < ActionController::TestCase
     with_restful_routing(:scrolls) do
       get :index, params: { id: "feed_with_atomPub_namespace" }
       assert_match %r{xml:lang="en-US"}, @response.body
-      assert_match %r{xmlns="http://www.w3.org/2005/Atom"}, @response.body
-      assert_match %r{xmlns:app="http://www.w3.org/2007/app"}, @response.body
+      assert_match %r{xmlns="http://www\.w3\.org/2005/Atom"}, @response.body
+      assert_match %r{xmlns:app="http://www\.w3\.org/2007/app"}, @response.body
     end
   end
 
   def test_feed_should_allow_overriding_ids
     with_restful_routing(:scrolls) do
       get :index, params: { id: "feed_with_overridden_ids" }
-      assert_select "id", :text => "tag:test.rubyonrails.org,2008:test/"
-      assert_select "entry id", :text => "tag:test.rubyonrails.org,2008:1"
-      assert_select "entry id", :text => "tag:test.rubyonrails.org,2008:2"
+      assert_select "id", text: "tag:test.rubyonrails.org,2008:test/"
+      assert_select "entry id", text: "tag:test.rubyonrails.org,2008:1"
+      assert_select "entry id", text: "tag:test.rubyonrails.org,2008:2"
     end
   end
 
   def test_feed_xml_processing_instructions
     with_restful_routing(:scrolls) do
-      get :index, params: { id: 'feed_with_xml_processing_instructions' }
+      get :index, params: { id: "feed_with_xml_processing_instructions" }
       assert_match %r{<\?xml-stylesheet [^\?]*type="text/css"}, @response.body
-      assert_match %r{<\?xml-stylesheet [^\?]*href="t.css"}, @response.body
+      assert_match %r{<\?xml-stylesheet [^\?]*href="t\.css"}, @response.body
     end
   end
 
   def test_feed_xml_processing_instructions_duplicate_targets
     with_restful_routing(:scrolls) do
-      get :index, params: { id: 'feed_with_xml_processing_instructions_duplicate_targets' }
+      get :index, params: { id: "feed_with_xml_processing_instructions_duplicate_targets" }
       assert_match %r{<\?target1 (a="1" b="2"|b="2" a="1")\?>}, @response.body
       assert_match %r{<\?target1 (c="3" d="4"|d="4" c="3")\?>}, @response.body
     end
@@ -334,29 +336,29 @@ class AtomFeedTest < ActionController::TestCase
   def test_feed_xhtml
     with_restful_routing(:scrolls) do
       get :index, params: { id:  "feed_with_xhtml_content" }
-      assert_match %r{xmlns="http://www.w3.org/1999/xhtml"}, @response.body
-      assert_select "summary", :text => /Something Boring/
-      assert_select "summary", :text => /after 2/
+      assert_match %r{xmlns="http://www\.w3\.org/1999/xhtml"}, @response.body
+      assert_select "summary", text: /Something Boring/
+      assert_select "summary", text: /after 2/
     end
   end
 
   def test_feed_entry_type_option_default_to_text_html
     with_restful_routing(:scrolls) do
-      get :index, params: { id: 'defaults' }
+      get :index, params: { id: "defaults" }
       assert_select "entry link[rel=alternate][type=\"text/html\"]"
     end
   end
 
   def test_feed_entry_type_option_specified
     with_restful_routing(:scrolls) do
-      get :index, params: { id: 'entry_type_options' }
+      get :index, params: { id: "entry_type_options" }
       assert_select "entry link[rel=alternate][type=\"text/xml\"]"
     end
   end
 
   def test_feed_entry_url_false_option_adds_no_link
     with_restful_routing(:scrolls) do
-      get :index, params: { id: 'entry_url_false_option' }
+      get :index, params: { id: "entry_url_false_option" }
       assert_select "entry link", false
     end
   end
diff --git a/actionview/test/template/capture_helper_test.rb b/actionview/test/template/capture_helper_test.rb
index ffaf773c53..8a1c00fd00 100644
--- a/actionview/test/template/capture_helper_test.rb
+++ b/actionview/test/template/capture_helper_test.rb
@@ -1,4 +1,6 @@
-require 'abstract_unit'
+# frozen_string_literal: true
+
+require "abstract_unit"
 
 class CaptureHelperTest < ActionView::TestCase
   def setup
@@ -10,18 +12,18 @@ class CaptureHelperTest < ActionView::TestCase
   def test_capture_captures_the_temporary_output_buffer_in_its_block
     assert_nil @av.output_buffer
     string = @av.capture do
-      @av.output_buffer << 'foo'
-      @av.output_buffer << 'bar'
+      @av.output_buffer << "foo"
+      @av.output_buffer << "bar"
     end
     assert_nil @av.output_buffer
-    assert_equal 'foobar', string
+    assert_equal "foobar", string
   end
 
   def test_capture_captures_the_value_returned_by_the_block_if_the_temporary_buffer_is_blank
-    string = @av.capture('foo', 'bar') do |a, b|
+    string = @av.capture("foo", "bar") do |a, b|
       a + b
     end
-    assert_equal 'foobar', string
+    assert_equal "foobar", string
   end
 
   def test_capture_returns_nil_if_the_returned_value_is_not_a_string
@@ -29,121 +31,121 @@ class CaptureHelperTest < ActionView::TestCase
   end
 
   def test_capture_escapes_html
-    string = @av.capture { '<em>bar</em>' }
-    assert_equal '&lt;em&gt;bar&lt;/em&gt;', string
+    string = @av.capture { "<em>bar</em>" }
+    assert_equal "&lt;em&gt;bar&lt;/em&gt;", string
   end
 
   def test_capture_doesnt_escape_twice
-    string = @av.capture { raw('&lt;em&gt;bar&lt;/em&gt;') }
-    assert_equal '&lt;em&gt;bar&lt;/em&gt;', string
+    string = @av.capture { raw("&lt;em&gt;bar&lt;/em&gt;") }
+    assert_equal "&lt;em&gt;bar&lt;/em&gt;", string
   end
 
   def test_capture_used_for_read
     content_for :foo, "foo"
     assert_equal "foo", content_for(:foo)
 
-    content_for(:bar){ "bar" }
+    content_for(:bar) { "bar" }
     assert_equal "bar", content_for(:bar)
   end
 
   def test_content_for_with_multiple_calls
     assert ! content_for?(:title)
-    content_for :title, 'foo'
-    content_for :title, 'bar'
-    assert_equal 'foobar', content_for(:title)
+    content_for :title, "foo"
+    content_for :title, "bar"
+    assert_equal "foobar", content_for(:title)
   end
 
   def test_content_for_with_multiple_calls_and_flush
     assert ! content_for?(:title)
-    content_for :title, 'foo'
-    content_for :title, 'bar', flush: true
-    assert_equal 'bar', content_for(:title)
+    content_for :title, "foo"
+    content_for :title, "bar", flush: true
+    assert_equal "bar", content_for(:title)
   end
 
   def test_content_for_with_block
     assert ! content_for?(:title)
     content_for :title do
-      output_buffer << 'foo'
-      output_buffer << 'bar'
+      output_buffer << "foo"
+      output_buffer << "bar"
       nil
     end
-    assert_equal 'foobar', content_for(:title)
+    assert_equal "foobar", content_for(:title)
   end
 
   def test_content_for_with_block_and_multiple_calls_with_flush
     assert ! content_for?(:title)
     content_for :title do
-      'foo'
+      "foo"
     end
     content_for :title, flush: true do
-      'bar'
+      "bar"
     end
-    assert_equal 'bar', content_for(:title)
+    assert_equal "bar", content_for(:title)
   end
 
   def test_content_for_with_block_and_multiple_calls_with_flush_nil_content
     assert ! content_for?(:title)
     content_for :title do
-      'foo'
+      "foo"
     end
     content_for :title, nil, flush: true do
-      'bar'
+      "bar"
     end
-    assert_equal 'bar', content_for(:title)
+    assert_equal "bar", content_for(:title)
   end
 
   def test_content_for_with_block_and_multiple_calls_without_flush
     assert ! content_for?(:title)
     content_for :title do
-      'foo'
+      "foo"
     end
     content_for :title, flush: false do
-      'bar'
+      "bar"
     end
-    assert_equal 'foobar', content_for(:title)
+    assert_equal "foobar", content_for(:title)
   end
 
   def test_content_for_with_whitespace_block
     assert ! content_for?(:title)
-    content_for :title, 'foo'
+    content_for :title, "foo"
     content_for :title do
       output_buffer << "  \n  "
       nil
     end
-    content_for :title, 'bar'
-    assert_equal 'foobar', content_for(:title)
+    content_for :title, "bar"
+    assert_equal "foobar", content_for(:title)
   end
 
   def test_content_for_with_whitespace_block_and_flush
     assert ! content_for?(:title)
-    content_for :title, 'foo'
+    content_for :title, "foo"
     content_for :title, flush: true do
       output_buffer << "  \n  "
       nil
     end
-    content_for :title, 'bar', flush: true
-    assert_equal 'bar', content_for(:title)
+    content_for :title, "bar", flush: true
+    assert_equal "bar", content_for(:title)
   end
 
   def test_content_for_returns_nil_when_writing
     assert ! content_for?(:title)
-    assert_equal nil, content_for(:title, 'foo')
-    assert_equal nil, content_for(:title) { output_buffer << 'bar'; nil }
-    assert_equal nil, content_for(:title) { output_buffer << "  \n  "; nil }
-    assert_equal 'foobar', content_for(:title)
-    assert_equal nil, content_for(:title, 'foo', flush: true)
-    assert_equal nil, content_for(:title, flush: true) { output_buffer << 'bar'; nil }
-    assert_equal nil, content_for(:title, flush: true) { output_buffer << "  \n  "; nil }
-    assert_equal 'bar', content_for(:title)
+    assert_nil content_for(:title, "foo")
+    assert_nil content_for(:title) { output_buffer << "bar"; nil }
+    assert_nil content_for(:title) { output_buffer << "  \n  "; nil }
+    assert_equal "foobar", content_for(:title)
+    assert_nil content_for(:title, "foo", flush: true)
+    assert_nil content_for(:title, flush: true) { output_buffer << "bar"; nil }
+    assert_nil content_for(:title, flush: true) { output_buffer << "  \n  "; nil }
+    assert_equal "bar", content_for(:title)
   end
 
   def test_content_for_returns_nil_when_content_missing
-    assert_equal nil, content_for(:some_missing_key)
+    assert_nil content_for(:some_missing_key)
   end
 
   def test_content_for_question_mark
     assert ! content_for?(:title)
-    content_for :title, 'title'
+    content_for :title, "title"
     assert content_for?(:title)
     assert ! content_for?(:something_else)
   end
@@ -151,12 +153,12 @@ class CaptureHelperTest < ActionView::TestCase
   def test_content_for_should_be_html_safe_after_flush_empty
     assert ! content_for?(:title)
     content_for :title do
-      content_tag(:p, 'title')
+      content_tag(:p, "title")
     end
     assert content_for(:title).html_safe?
     content_for :title, "", flush: true
     content_for(:title) do
-      content_tag(:p, 'title')
+      content_tag(:p, "title")
     end
     assert content_for(:title).html_safe?
   end
@@ -178,19 +180,19 @@ class CaptureHelperTest < ActionView::TestCase
   def test_with_output_buffer_swaps_the_output_buffer_given_no_argument
     assert_nil @av.output_buffer
     buffer = @av.with_output_buffer do
-      @av.output_buffer << '.'
+      @av.output_buffer << "."
     end
-    assert_equal '.', buffer
+    assert_equal ".", buffer
     assert_nil @av.output_buffer
   end
 
   def test_with_output_buffer_swaps_the_output_buffer_with_an_argument
     assert_nil @av.output_buffer
-    buffer = ActionView::OutputBuffer.new('.')
+    buffer = ActionView::OutputBuffer.new(".")
     @av.with_output_buffer(buffer) do
-      @av.output_buffer << '.'
+      @av.output_buffer << "."
     end
-    assert_equal '..', buffer
+    assert_equal "..", buffer
     assert_nil @av.output_buffer
   end
 
@@ -198,7 +200,7 @@ class CaptureHelperTest < ActionView::TestCase
     buffer = ActionView::OutputBuffer.new
     @av.output_buffer = buffer
     @av.with_output_buffer do
-      @av.output_buffer << '.'
+      @av.output_buffer << "."
     end
     assert buffer.equal?(@av.output_buffer)
   end
diff --git a/actionview/test/template/compiled_templates_test.rb b/actionview/test/template/compiled_templates_test.rb
index f6c1283b92..3cd6448e38 100644
--- a/actionview/test/template/compiled_templates_test.rb
+++ b/actionview/test/template/compiled_templates_test.rb
@@ -1,4 +1,6 @@
-require 'abstract_unit'
+# frozen_string_literal: true
+
+require "abstract_unit"
 
 class CompiledTemplatesTest < ActiveSupport::TestCase
   teardown do
@@ -6,28 +8,61 @@ class CompiledTemplatesTest < ActiveSupport::TestCase
   end
 
   def test_template_with_nil_erb_return
-    assert_equal "This is nil: \n", render(:template => "test/nil_return")
+    assert_equal "This is nil: \n", render(template: "test/nil_return")
+  end
+
+  def test_template_with_ruby_keyword_locals
+    assert_equal "The class is foo",
+      render(file: "test/render_file_with_ruby_keyword_locals", locals: { class: "foo" })
+  end
+
+  def test_template_with_invalid_identifier_locals
+    locals = {
+      foo: "bar",
+      Foo: "bar",
+      "d-a-s-h-e-s": "",
+      "white space": "",
+    }
+    assert_equal locals.inspect, render(file: "test/render_file_inspect_local_assigns", locals: locals)
+  end
+
+  def test_template_with_delegation_reserved_keywords
+    locals = {
+      _: "one",
+      arg: "two",
+      args: "three",
+      block: "four",
+    }
+    assert_equal "one two three four", render(file: "test/test_template_with_delegation_reserved_keywords", locals: locals)
+  end
+
+  def test_template_with_unicode_identifier
+    assert_equal "🎂", render(file: "test/render_file_unicode_local", locals: { 🎃: "🎂" })
+  end
+
+  def test_template_with_instance_variable_identifier
+    assert_equal "bar", render(file: "test/render_file_instance_variable", locals: { "@foo": "bar" })
   end
 
   def test_template_gets_recompiled_when_using_different_keys_in_local_assigns
-    assert_equal "one", render(:file => "test/render_file_with_locals_and_default")
-    assert_equal "two", render(:file => "test/render_file_with_locals_and_default", :locals => { :secret => "two" })
+    assert_equal "one", render(file: "test/render_file_with_locals_and_default")
+    assert_equal "two", render(file: "test/render_file_with_locals_and_default", locals: { secret: "two" })
   end
 
   def test_template_changes_are_not_reflected_with_cached_templates
-    assert_equal "Hello world!", render(:file => "test/hello_world")
+    assert_equal "Hello world!", render(file: "test/hello_world")
     modify_template "test/hello_world.erb", "Goodbye world!" do
-      assert_equal "Hello world!", render(:file => "test/hello_world")
+      assert_equal "Hello world!", render(file: "test/hello_world")
     end
-    assert_equal "Hello world!", render(:file => "test/hello_world")
+    assert_equal "Hello world!", render(file: "test/hello_world")
   end
 
   def test_template_changes_are_reflected_with_uncached_templates
-    assert_equal "Hello world!", render_without_cache(:file => "test/hello_world")
+    assert_equal "Hello world!", render_without_cache(file: "test/hello_world")
     modify_template "test/hello_world.erb", "Goodbye world!" do
-      assert_equal "Goodbye world!", render_without_cache(:file => "test/hello_world")
+      assert_equal "Goodbye world!", render_without_cache(file: "test/hello_world")
     end
-    assert_equal "Hello world!", render_without_cache(:file => "test/hello_world")
+    assert_equal "Hello world!", render_without_cache(file: "test/hello_world")
   end
 
   private
diff --git a/actionview/test/template/controller_helper_test.rb b/actionview/test/template/controller_helper_test.rb
index b5e94ea4f1..46d20c188c 100644
--- a/actionview/test/template/controller_helper_test.rb
+++ b/actionview/test/template/controller_helper_test.rb
@@ -1,4 +1,6 @@
-require 'abstract_unit'
+# frozen_string_literal: true
+
+require "abstract_unit"
 
 class ControllerHelperTest < ActionView::TestCase
   tests ActionView::Helpers::ControllerHelper
@@ -9,13 +11,24 @@ class ControllerHelperTest < ActionView::TestCase
     @controller = OpenStruct.new(default_form_builder: SpecializedFormBuilder)
     assign_controller(@controller)
 
-    assert_equal SpecializedFormBuilder, self.default_form_builder
+    assert_equal SpecializedFormBuilder, default_form_builder
   end
 
   def test_assign_controller_skips_default_form_builder
     @controller = OpenStruct.new
     assign_controller(@controller)
 
-    assert_nil self.default_form_builder
+    assert_nil default_form_builder
+  end
+
+  def test_respond_to
+    @controller = OpenStruct.new
+    assign_controller(@controller)
+    assert_not respond_to?(:params)
+    assert respond_to?(:assign_controller)
+
+    @controller.params = {}
+    assert respond_to?(:params)
+    assert respond_to?(:assign_controller)
   end
 end
diff --git a/actionview/test/template/date_helper_i18n_test.rb b/actionview/test/template/date_helper_i18n_test.rb
index 52aef56a61..60303b4c91 100644
--- a/actionview/test/template/date_helper_i18n_test.rb
+++ b/actionview/test/template/date_helper_i18n_test.rb
@@ -1,4 +1,6 @@
-require 'abstract_unit'
+# frozen_string_literal: true
+
+require "abstract_unit"
 
 class DateHelperDistanceOfTimeInWordsI18nTests < ActiveSupport::TestCase
   include ActionView::Helpers::DateHelper
@@ -12,24 +14,24 @@ class DateHelperDistanceOfTimeInWordsI18nTests < ActiveSupport::TestCase
 
   def test_distance_of_time_in_words_calls_i18n
     { # with include_seconds
-      [2.seconds,  { :include_seconds => true }]  => [:'less_than_x_seconds', 5],
-      [9.seconds,  { :include_seconds => true }]  => [:'less_than_x_seconds', 10],
-      [19.seconds, { :include_seconds => true }]  => [:'less_than_x_seconds', 20],
-      [30.seconds, { :include_seconds => true }]  => [:'half_a_minute',       nil],
-      [59.seconds, { :include_seconds => true }]  => [:'less_than_x_minutes', 1],
-      [60.seconds, { :include_seconds => true }]  => [:'x_minutes',           1],
+      [2.seconds,  { include_seconds: true }]  => [:'less_than_x_seconds', 5],
+      [9.seconds,  { include_seconds: true }]  => [:'less_than_x_seconds', 10],
+      [19.seconds, { include_seconds: true }]  => [:'less_than_x_seconds', 20],
+      [30.seconds, { include_seconds: true }]  => [:'half_a_minute',       nil],
+      [59.seconds, { include_seconds: true }]  => [:'less_than_x_minutes', 1],
+      [60.seconds, { include_seconds: true }]  => [:'x_minutes',           1],
 
       # without include_seconds
-      [29.seconds,          { :include_seconds => false }] => [:'less_than_x_minutes', 1],
-      [60.seconds,          { :include_seconds => false }] => [:'x_minutes',           1],
-      [44.minutes,          { :include_seconds => false }] => [:'x_minutes',           44],
-      [61.minutes,          { :include_seconds => false }] => [:'about_x_hours',       1],
-      [24.hours,            { :include_seconds => false }] => [:'x_days',              1],
-      [30.days,             { :include_seconds => false }] => [:'about_x_months',      1],
-      [60.days,             { :include_seconds => false }] => [:'x_months',            2],
-      [1.year,              { :include_seconds => false }] => [:'about_x_years',       1],
-      [3.years + 6.months,  { :include_seconds => false }] => [:'over_x_years',        3],
-      [3.years + 10.months, { :include_seconds => false }] => [:'almost_x_years',      4]
+      [29.seconds,          { include_seconds: false }] => [:'less_than_x_minutes', 1],
+      [60.seconds,          { include_seconds: false }] => [:'x_minutes',           1],
+      [44.minutes,          { include_seconds: false }] => [:'x_minutes',           44],
+      [61.minutes,          { include_seconds: false }] => [:'about_x_hours',       1],
+      [24.hours,            { include_seconds: false }] => [:'x_days',              1],
+      [30.days,             { include_seconds: false }] => [:'about_x_months',      1],
+      [60.days,             { include_seconds: false }] => [:'x_months',            2],
+      [1.year,              { include_seconds: false }] => [:'about_x_years',       1],
+      [3.years + 6.months,  { include_seconds: false }] => [:'over_x_years',        3],
+      [3.years + 10.months, { include_seconds: false }] => [:'almost_x_years',      4]
 
       }.each do |passed, expected|
       assert_distance_of_time_in_words_translates_key passed, expected
@@ -46,30 +48,30 @@ class DateHelperDistanceOfTimeInWordsI18nTests < ActiveSupport::TestCase
   end
 
   def test_time_ago_in_words_passes_locale
-    assert_called_with(I18n, :t, [:less_than_x_minutes, :scope => :'datetime.distance_in_words', :count => 1, :locale => 'ru']) do
-      time_ago_in_words(15.seconds.ago, :locale => 'ru')
+    assert_called_with(I18n, :t, [:less_than_x_minutes, scope: :'datetime.distance_in_words', count: 1, locale: "ru"]) do
+      time_ago_in_words(15.seconds.ago, locale: "ru")
     end
   end
 
   def test_distance_of_time_pluralizations
-    { [:'less_than_x_seconds', 1]   => 'less than 1 second',
-      [:'less_than_x_seconds', 2]   => 'less than 2 seconds',
-      [:'less_than_x_minutes', 1]   => 'less than a minute',
-      [:'less_than_x_minutes', 2]   => 'less than 2 minutes',
-      [:'x_minutes',           1]   => '1 minute',
-      [:'x_minutes',           2]   => '2 minutes',
-      [:'about_x_hours',       1]   => 'about 1 hour',
-      [:'about_x_hours',       2]   => 'about 2 hours',
-      [:'x_days',              1]   => '1 day',
-      [:'x_days',              2]   => '2 days',
-      [:'about_x_years',       1]   => 'about 1 year',
-      [:'about_x_years',       2]   => 'about 2 years',
-      [:'over_x_years',        1]   => 'over 1 year',
-      [:'over_x_years',        2]   => 'over 2 years'
+    { [:'less_than_x_seconds', 1]   => "less than 1 second",
+      [:'less_than_x_seconds', 2]   => "less than 2 seconds",
+      [:'less_than_x_minutes', 1]   => "less than a minute",
+      [:'less_than_x_minutes', 2]   => "less than 2 minutes",
+      [:'x_minutes',           1]   => "1 minute",
+      [:'x_minutes',           2]   => "2 minutes",
+      [:'about_x_hours',       1]   => "about 1 hour",
+      [:'about_x_hours',       2]   => "about 2 hours",
+      [:'x_days',              1]   => "1 day",
+      [:'x_days',              2]   => "2 days",
+      [:'about_x_years',       1]   => "about 1 year",
+      [:'about_x_years',       2]   => "about 2 years",
+      [:'over_x_years',        1]   => "over 1 year",
+      [:'over_x_years',        2]   => "over 2 years"
 
       }.each do |args, expected|
       key, count = *args
-      assert_equal expected, I18n.t(key, :count => count, :scope => 'datetime.distance_in_words')
+      assert_equal expected, I18n.t(key, count: count, scope: "datetime.distance_in_words")
     end
   end
 
@@ -78,11 +80,11 @@ class DateHelperDistanceOfTimeInWordsI18nTests < ActiveSupport::TestCase
     key, count = *expected
     to = @from + diff
 
-    options = { locale: 'en', scope: :'datetime.distance_in_words' }.merge!(expected_options)
+    options = { locale: "en", scope: :'datetime.distance_in_words' }.merge!(expected_options)
     options[:count] = count if count
 
     assert_called_with(I18n, :t, [key, options]) do
-      distance_of_time_in_words(@from, to, passed_options.merge(locale: 'en'))
+      distance_of_time_in_words(@from, to, passed_options.merge(locale: "en"))
     end
   end
 end
@@ -95,28 +97,28 @@ class DateHelperSelectTagsI18nTests < ActiveSupport::TestCase
 
   def test_select_month_given_use_month_names_option_does_not_translate_monthnames
     assert_not_called(I18n, :translate) do
-      select_month(8, :locale => 'en', :use_month_names => Date::MONTHNAMES)
+      select_month(8, locale: "en", use_month_names: Date::MONTHNAMES)
     end
   end
 
   def test_select_month_translates_monthnames
-    assert_called_with(I18n, :translate, [:'date.month_names', :locale => 'en'], returns: Date::MONTHNAMES) do
-      select_month(8, :locale => 'en')
+    assert_called_with(I18n, :translate, [:'date.month_names', locale: "en"], returns: Date::MONTHNAMES) do
+      select_month(8, locale: "en")
     end
   end
 
   def test_select_month_given_use_short_month_option_translates_abbr_monthnames
-    assert_called_with(I18n, :translate, [:'date.abbr_month_names', :locale => 'en'], returns: Date::ABBR_MONTHNAMES) do
-      select_month(8, :locale => 'en', :use_short_month => true)
+    assert_called_with(I18n, :translate, [:'date.abbr_month_names', locale: "en"], returns: Date::ABBR_MONTHNAMES) do
+      select_month(8, locale: "en", use_short_month: true)
     end
   end
 
   def test_date_or_time_select_translates_prompts
-    prompt_defaults = {:year => 'Year', :month => 'Month', :day => 'Day', :hour => 'Hour', :minute => 'Minute', :second => 'Seconds'}
-    defaults = {[:'date.order', :locale => 'en', :default => []] => %w(year month day)}
+    prompt_defaults = { year: "Year", month: "Month", day: "Day", hour: "Hour", minute: "Minute", second: "Seconds" }
+    defaults = { [:'date.order', locale: "en", default: []] => %w(year month day) }
 
     prompt_defaults.each do |key, prompt|
-      defaults[[('datetime.prompts.' + key.to_s).to_sym, :locale => 'en']] = prompt
+      defaults[[("datetime.prompts." + key.to_s).to_sym, locale: "en"]] = prompt
     end
 
     prompts_check = -> (prompt, x) do
@@ -129,7 +131,7 @@ class DateHelperSelectTagsI18nTests < ActiveSupport::TestCase
     end
 
     I18n.stub(:translate, prompts_check) do
-      datetime_select('post', 'updated_at', :locale => 'en', :include_seconds => true, :prompt => true, :use_month_names => Date::MONTHNAMES)
+      datetime_select("post", "updated_at", locale: "en", include_seconds: true, prompt: true, use_month_names: Date::MONTHNAMES)
     end
     assert_equal defaults.count, @prompt_called
   end
@@ -138,27 +140,27 @@ class DateHelperSelectTagsI18nTests < ActiveSupport::TestCase
 
   def test_date_or_time_select_given_an_order_options_does_not_translate_order
     assert_not_called(I18n, :translate) do
-      datetime_select('post', 'updated_at', :order => [:year, :month, :day], :locale => 'en', :use_month_names => Date::MONTHNAMES)
+      datetime_select("post", "updated_at", order: [:year, :month, :day], locale: "en", use_month_names: Date::MONTHNAMES)
     end
   end
 
   def test_date_or_time_select_given_no_order_options_translates_order
-    assert_called_with(I18n, :translate, [ [:'date.order', :locale => 'en', :default => []], [:"date.month_names", {:locale=>"en"}] ], returns: %w(year month day)) do
-      datetime_select('post', 'updated_at', :locale => 'en')
+    assert_called_with(I18n, :translate, [ [:'date.order', locale: "en", default: []], [:"date.month_names", { locale: "en" }] ], returns: %w(year month day)) do
+      datetime_select("post", "updated_at", locale: "en")
     end
   end
 
   def test_date_or_time_select_given_invalid_order
-    assert_called_with(I18n, :translate, [:'date.order', :locale => 'en', :default => []], returns: %w(invalid month day)) do
+    assert_called_with(I18n, :translate, [:'date.order', locale: "en", default: []], returns: %w(invalid month day)) do
       assert_raise StandardError do
-        datetime_select('post', 'updated_at', :locale => 'en')
+        datetime_select("post", "updated_at", locale: "en")
       end
     end
   end
 
   def test_date_or_time_select_given_symbol_keys
-    assert_called_with(I18n, :translate, [ [:'date.order', :locale => 'en', :default => []], [:"date.month_names", {:locale=>"en"}] ], returns: [:year, :month, :day]) do
-      datetime_select('post', 'updated_at', :locale => 'en')
+    assert_called_with(I18n, :translate, [ [:'date.order', locale: "en", default: []], [:"date.month_names", { locale: "en" }] ], returns: [:year, :month, :day]) do
+      datetime_select("post", "updated_at", locale: "en")
     end
   end
 end
diff --git a/actionview/test/template/date_helper_test.rb b/actionview/test/template/date_helper_test.rb
index e67d5d0e8c..97cfd754be 100644
--- a/actionview/test/template/date_helper_test.rb
+++ b/actionview/test/template/date_helper_test.rb
@@ -1,4 +1,6 @@
-require 'abstract_unit'
+# frozen_string_literal: true
+
+require "abstract_unit"
 
 class DateHelperTest < ActionView::TestCase
   tests ActionView::Helpers::DateHelper
@@ -13,41 +15,41 @@ class DateHelperTest < ActionView::TestCase
         123
       end
       def to_param
-        '123'
+        "123"
       end
     end
   end
 
-  def assert_distance_of_time_in_words(from, to=nil)
+  def assert_distance_of_time_in_words(from, to = nil)
     to ||= from
 
     # 0..1 minute with :include_seconds => true
-    assert_equal "less than 5 seconds", distance_of_time_in_words(from, to + 0.seconds, :include_seconds => true)
-    assert_equal "less than 5 seconds", distance_of_time_in_words(from, to + 4.seconds, :include_seconds => true)
-    assert_equal "less than 10 seconds", distance_of_time_in_words(from, to + 5.seconds, :include_seconds => true)
-    assert_equal "less than 10 seconds", distance_of_time_in_words(from, to + 9.seconds, :include_seconds => true)
-    assert_equal "less than 20 seconds", distance_of_time_in_words(from, to + 10.seconds, :include_seconds => true)
-    assert_equal "less than 20 seconds", distance_of_time_in_words(from, to + 19.seconds, :include_seconds => true)
-    assert_equal "half a minute", distance_of_time_in_words(from, to + 20.seconds, :include_seconds => true)
-    assert_equal "half a minute", distance_of_time_in_words(from, to + 39.seconds, :include_seconds => true)
-    assert_equal "less than a minute", distance_of_time_in_words(from, to + 40.seconds, :include_seconds => true)
-    assert_equal "less than a minute", distance_of_time_in_words(from, to + 59.seconds, :include_seconds => true)
-    assert_equal "1 minute", distance_of_time_in_words(from, to + 60.seconds, :include_seconds => true)
-    assert_equal "1 minute", distance_of_time_in_words(from, to + 89.seconds, :include_seconds => true)
+    assert_equal "less than 5 seconds", distance_of_time_in_words(from, to + 0.seconds, include_seconds: true)
+    assert_equal "less than 5 seconds", distance_of_time_in_words(from, to + 4.seconds, include_seconds: true)
+    assert_equal "less than 10 seconds", distance_of_time_in_words(from, to + 5.seconds, include_seconds: true)
+    assert_equal "less than 10 seconds", distance_of_time_in_words(from, to + 9.seconds, include_seconds: true)
+    assert_equal "less than 20 seconds", distance_of_time_in_words(from, to + 10.seconds, include_seconds: true)
+    assert_equal "less than 20 seconds", distance_of_time_in_words(from, to + 19.seconds, include_seconds: true)
+    assert_equal "half a minute", distance_of_time_in_words(from, to + 20.seconds, include_seconds: true)
+    assert_equal "half a minute", distance_of_time_in_words(from, to + 39.seconds, include_seconds: true)
+    assert_equal "less than a minute", distance_of_time_in_words(from, to + 40.seconds, include_seconds: true)
+    assert_equal "less than a minute", distance_of_time_in_words(from, to + 59.seconds, include_seconds: true)
+    assert_equal "1 minute", distance_of_time_in_words(from, to + 60.seconds, include_seconds: true)
+    assert_equal "1 minute", distance_of_time_in_words(from, to + 89.seconds, include_seconds: true)
 
     # 0..1 minute with :include_seconds => false
-    assert_equal "less than a minute", distance_of_time_in_words(from, to + 0.seconds, :include_seconds => false)
-    assert_equal "less than a minute", distance_of_time_in_words(from, to + 4.seconds, :include_seconds => false)
-    assert_equal "less than a minute", distance_of_time_in_words(from, to + 5.seconds, :include_seconds => false)
-    assert_equal "less than a minute", distance_of_time_in_words(from, to + 9.seconds, :include_seconds => false)
-    assert_equal "less than a minute", distance_of_time_in_words(from, to + 10.seconds, :include_seconds => false)
-    assert_equal "less than a minute", distance_of_time_in_words(from, to + 19.seconds, :include_seconds => false)
-    assert_equal "less than a minute", distance_of_time_in_words(from, to + 20.seconds, :include_seconds => false)
-    assert_equal "1 minute", distance_of_time_in_words(from, to + 39.seconds, :include_seconds => false)
-    assert_equal "1 minute", distance_of_time_in_words(from, to + 40.seconds, :include_seconds => false)
-    assert_equal "1 minute", distance_of_time_in_words(from, to + 59.seconds, :include_seconds => false)
-    assert_equal "1 minute", distance_of_time_in_words(from, to + 60.seconds, :include_seconds => false)
-    assert_equal "1 minute", distance_of_time_in_words(from, to + 89.seconds, :include_seconds => false)
+    assert_equal "less than a minute", distance_of_time_in_words(from, to + 0.seconds, include_seconds: false)
+    assert_equal "less than a minute", distance_of_time_in_words(from, to + 4.seconds, include_seconds: false)
+    assert_equal "less than a minute", distance_of_time_in_words(from, to + 5.seconds, include_seconds: false)
+    assert_equal "less than a minute", distance_of_time_in_words(from, to + 9.seconds, include_seconds: false)
+    assert_equal "less than a minute", distance_of_time_in_words(from, to + 10.seconds, include_seconds: false)
+    assert_equal "less than a minute", distance_of_time_in_words(from, to + 19.seconds, include_seconds: false)
+    assert_equal "less than a minute", distance_of_time_in_words(from, to + 20.seconds, include_seconds: false)
+    assert_equal "1 minute", distance_of_time_in_words(from, to + 39.seconds, include_seconds: false)
+    assert_equal "1 minute", distance_of_time_in_words(from, to + 40.seconds, include_seconds: false)
+    assert_equal "1 minute", distance_of_time_in_words(from, to + 59.seconds, include_seconds: false)
+    assert_equal "1 minute", distance_of_time_in_words(from, to + 60.seconds, include_seconds: false)
+    assert_equal "1 minute", distance_of_time_in_words(from, to + 89.seconds, include_seconds: false)
 
     # Note that we are including a 30-second boundary around the interval we
     # want to test. For instance, "1 minute" is actually 30s to 1m29s. The
@@ -119,8 +121,8 @@ class DateHelperTest < ActionView::TestCase
 
     # test to < from
     assert_equal "about 4 hours", distance_of_time_in_words(from + 4.hours, to)
-    assert_equal "less than 20 seconds", distance_of_time_in_words(from + 19.seconds, to, :include_seconds => true)
-    assert_equal "less than a minute", distance_of_time_in_words(from + 19.seconds, to, :include_seconds => false)
+    assert_equal "less than 20 seconds", distance_of_time_in_words(from + 19.seconds, to, include_seconds: true)
+    assert_equal "less than a minute", distance_of_time_in_words(from + 19.seconds, to, include_seconds: false)
   end
 
   def test_distance_in_words
@@ -128,29 +130,47 @@ class DateHelperTest < ActionView::TestCase
     assert_distance_of_time_in_words(from)
   end
 
-  def test_distance_in_words_with_mathn_required
-    # test we avoid Integer#/ (redefined by mathn)
-    silence_warnings { require "mathn" }
+  def test_distance_in_words_with_nil_input
+    assert_raises(ArgumentError) { distance_of_time_in_words(nil) }
+    assert_raises(ArgumentError) { distance_of_time_in_words(0, nil) }
+  end
+
+  def test_distance_in_words_with_mixed_argument_types
+    assert_equal "1 minute", distance_of_time_in_words(0, Time.at(60))
+    assert_equal "10 minutes", distance_of_time_in_words(Time.at(600), 0)
+  end
+
+  def test_distance_in_words_doesnt_use_the_quotient_operator
+    rubinius_skip "Date is written in Ruby and relies on Fixnum#/"
+    jruby_skip "Date is written in Ruby and relies on Fixnum#/"
+
+    klass = RUBY_VERSION > "2.4" ? Integer : Fixnum
+
+    # Make sure that we avoid {Integer,Fixnum}#/ (redefined by mathn)
+    klass.send :private, :/
+
     from = Time.utc(2004, 6, 6, 21, 45, 0)
     assert_distance_of_time_in_words(from)
+  ensure
+    klass.send :public, :/
   end
 
   def test_time_ago_in_words_passes_include_seconds
-    assert_equal "less than 20 seconds", time_ago_in_words(15.seconds.ago, :include_seconds => true)
-    assert_equal "less than a minute", time_ago_in_words(15.seconds.ago, :include_seconds => false)
+    assert_equal "less than 20 seconds", time_ago_in_words(15.seconds.ago, include_seconds: true)
+    assert_equal "less than a minute", time_ago_in_words(15.seconds.ago, include_seconds: false)
   end
 
   def test_distance_in_words_with_time_zones
     from = Time.mktime(2004, 6, 6, 21, 45, 0)
-    assert_distance_of_time_in_words(from.in_time_zone('Alaska'))
-    assert_distance_of_time_in_words(from.in_time_zone('Hawaii'))
+    assert_distance_of_time_in_words(from.in_time_zone("Alaska"))
+    assert_distance_of_time_in_words(from.in_time_zone("Hawaii"))
   end
 
   def test_distance_in_words_with_different_time_zones
     from = Time.mktime(2004, 6, 6, 21, 45, 0)
     assert_distance_of_time_in_words(
-      from.in_time_zone('Alaska'),
-      from.in_time_zone('Hawaii')
+      from.in_time_zone("Alaska"),
+      from.in_time_zone("Hawaii")
     )
   end
 
@@ -167,9 +187,9 @@ class DateHelperTest < ActionView::TestCase
 
   def test_distance_in_words_with_integers
     assert_equal "1 minute", distance_of_time_in_words(59)
-    assert_equal "about 1 hour", distance_of_time_in_words(60*60)
+    assert_equal "about 1 hour", distance_of_time_in_words(60 * 60)
     assert_equal "1 minute", distance_of_time_in_words(0, 59)
-    assert_equal "about 1 hour", distance_of_time_in_words(60*60, 0)
+    assert_equal "about 1 hour", distance_of_time_in_words(60 * 60, 0)
     assert_equal "about 3 years", distance_of_time_in_words(10**8)
     assert_equal "about 3 years", distance_of_time_in_words(0, 10**8)
   end
@@ -185,10 +205,10 @@ class DateHelperTest < ActionView::TestCase
     assert_equal "about 1 hour", distance_of_time_in_words(60.minutes)
 
     # include seconds
-    assert_equal "half a minute", distance_of_time_in_words(39.seconds, 0, :include_seconds => true)
-    assert_equal "less than a minute", distance_of_time_in_words(40.seconds, 0, :include_seconds => true)
-    assert_equal "less than a minute", distance_of_time_in_words(59.seconds, 0, :include_seconds => true)
-    assert_equal "1 minute", distance_of_time_in_words(60.seconds, 0, :include_seconds => true)
+    assert_equal "half a minute", distance_of_time_in_words(39.seconds, 0, include_seconds: true)
+    assert_equal "less than a minute", distance_of_time_in_words(40.seconds, 0, include_seconds: true)
+    assert_equal "less than a minute", distance_of_time_in_words(59.seconds, 0, include_seconds: true)
+    assert_equal "1 minute", distance_of_time_in_words(60.seconds, 0, include_seconds: true)
   end
 
   def test_time_ago_in_words
@@ -196,7 +216,7 @@ class DateHelperTest < ActionView::TestCase
   end
 
   def test_select_day
-    expected = %(<select id="date_day" name="date[day]">\n)
+    expected = %(<select id="date_day" name="date[day]">\n).dup
     expected << %(<option value="1">1</option>\n<option value="2">2</option>\n<option value="3">3</option>\n<option value="4">4</option>\n<option value="5">5</option>\n<option value="6">6</option>\n<option value="7">7</option>\n<option value="8">8</option>\n<option value="9">9</option>\n<option value="10">10</option>\n<option value="11">11</option>\n<option value="12">12</option>\n<option value="13">13</option>\n<option value="14">14</option>\n<option value="15">15</option>\n<option value="16" selected="selected">16</option>\n<option value="17">17</option>\n<option value="18">18</option>\n<option value="19">19</option>\n<option value="20">20</option>\n<option value="21">21</option>\n<option value="22">22</option>\n<option value="23">23</option>\n<option value="24">24</option>\n<option value="25">25</option>\n<option value="26">26</option>\n<option value="27">27</option>\n<option value="28">28</option>\n<option value="29">29</option>\n<option value="30">30</option>\n<option value="31">31</option>\n)
     expected << "</select>\n"
 
@@ -205,58 +225,58 @@ class DateHelperTest < ActionView::TestCase
   end
 
   def test_select_day_with_blank
-    expected = %(<select id="date_day" name="date[day]">\n)
+    expected = %(<select id="date_day" name="date[day]">\n).dup
     expected << %(<option value=""></option>\n<option value="1">1</option>\n<option value="2">2</option>\n<option value="3">3</option>\n<option value="4">4</option>\n<option value="5">5</option>\n<option value="6">6</option>\n<option value="7">7</option>\n<option value="8">8</option>\n<option value="9">9</option>\n<option value="10">10</option>\n<option value="11">11</option>\n<option value="12">12</option>\n<option value="13">13</option>\n<option value="14">14</option>\n<option value="15">15</option>\n<option value="16" selected="selected">16</option>\n<option value="17">17</option>\n<option value="18">18</option>\n<option value="19">19</option>\n<option value="20">20</option>\n<option value="21">21</option>\n<option value="22">22</option>\n<option value="23">23</option>\n<option value="24">24</option>\n<option value="25">25</option>\n<option value="26">26</option>\n<option value="27">27</option>\n<option value="28">28</option>\n<option value="29">29</option>\n<option value="30">30</option>\n<option value="31">31</option>\n)
     expected << "</select>\n"
 
-    assert_dom_equal expected, select_day(Time.mktime(2003, 8, 16), :include_blank => true)
-    assert_dom_equal expected, select_day(16, :include_blank => true)
+    assert_dom_equal expected, select_day(Time.mktime(2003, 8, 16), include_blank: true)
+    assert_dom_equal expected, select_day(16, include_blank: true)
   end
 
   def test_select_day_nil_with_blank
-    expected = %(<select id="date_day" name="date[day]">\n)
+    expected = %(<select id="date_day" name="date[day]">\n).dup
     expected << %(<option value=""></option>\n<option value="1">1</option>\n<option value="2">2</option>\n<option value="3">3</option>\n<option value="4">4</option>\n<option value="5">5</option>\n<option value="6">6</option>\n<option value="7">7</option>\n<option value="8">8</option>\n<option value="9">9</option>\n<option value="10">10</option>\n<option value="11">11</option>\n<option value="12">12</option>\n<option value="13">13</option>\n<option value="14">14</option>\n<option value="15">15</option>\n<option value="16">16</option>\n<option value="17">17</option>\n<option value="18">18</option>\n<option value="19">19</option>\n<option value="20">20</option>\n<option value="21">21</option>\n<option value="22">22</option>\n<option value="23">23</option>\n<option value="24">24</option>\n<option value="25">25</option>\n<option value="26">26</option>\n<option value="27">27</option>\n<option value="28">28</option>\n<option value="29">29</option>\n<option value="30">30</option>\n<option value="31">31</option>\n)
     expected << "</select>\n"
 
-    assert_dom_equal expected, select_day(nil, :include_blank => true)
+    assert_dom_equal expected, select_day(nil, include_blank: true)
   end
 
   def test_select_day_with_two_digit_numbers
-    expected = %(<select id="date_day" name="date[day]">\n)
+    expected = %(<select id="date_day" name="date[day]">\n).dup
     expected << %(<option value="1">01</option>\n<option selected="selected" value="2">02</option>\n<option value="3">03</option>\n<option value="4">04</option>\n<option value="5">05</option>\n<option value="6">06</option>\n<option value="7">07</option>\n<option value="8">08</option>\n<option value="9">09</option>\n<option value="10">10</option>\n<option value="11">11</option>\n<option value="12">12</option>\n<option value="13">13</option>\n<option value="14">14</option>\n<option value="15">15</option>\n<option value="16">16</option>\n<option value="17">17</option>\n<option value="18">18</option>\n<option value="19">19</option>\n<option value="20">20</option>\n<option value="21">21</option>\n<option value="22">22</option>\n<option value="23">23</option>\n<option value="24">24</option>\n<option value="25">25</option>\n<option value="26">26</option>\n<option value="27">27</option>\n<option value="28">28</option>\n<option value="29">29</option>\n<option value="30">30</option>\n<option value="31">31</option>\n)
     expected << "</select>\n"
 
-    assert_dom_equal expected, select_day(Time.mktime(2011, 8, 2), :use_two_digit_numbers => true)
-    assert_dom_equal expected, select_day(2, :use_two_digit_numbers => true)
+    assert_dom_equal expected, select_day(Time.mktime(2011, 8, 2), use_two_digit_numbers: true)
+    assert_dom_equal expected, select_day(2, use_two_digit_numbers: true)
   end
 
   def test_select_day_with_html_options
-    expected = %(<select id="date_day" name="date[day]" class="selector">\n)
+    expected = %(<select id="date_day" name="date[day]" class="selector">\n).dup
     expected << %(<option value="1">1</option>\n<option value="2">2</option>\n<option value="3">3</option>\n<option value="4">4</option>\n<option value="5">5</option>\n<option value="6">6</option>\n<option value="7">7</option>\n<option value="8">8</option>\n<option value="9">9</option>\n<option value="10">10</option>\n<option value="11">11</option>\n<option value="12">12</option>\n<option value="13">13</option>\n<option value="14">14</option>\n<option value="15">15</option>\n<option value="16" selected="selected">16</option>\n<option value="17">17</option>\n<option value="18">18</option>\n<option value="19">19</option>\n<option value="20">20</option>\n<option value="21">21</option>\n<option value="22">22</option>\n<option value="23">23</option>\n<option value="24">24</option>\n<option value="25">25</option>\n<option value="26">26</option>\n<option value="27">27</option>\n<option value="28">28</option>\n<option value="29">29</option>\n<option value="30">30</option>\n<option value="31">31</option>\n)
     expected << "</select>\n"
 
-    assert_dom_equal expected, select_day(Time.mktime(2003, 8, 16), {}, :class => 'selector')
-    assert_dom_equal expected, select_day(16, {}, :class => 'selector')
+    assert_dom_equal expected, select_day(Time.mktime(2003, 8, 16), {}, { class: "selector" })
+    assert_dom_equal expected, select_day(16, {}, { class: "selector" })
   end
 
   def test_select_day_with_default_prompt
-    expected = %(<select id="date_day" name="date[day]">\n)
+    expected = %(<select id="date_day" name="date[day]">\n).dup
     expected << %(<option value="">Day</option>\n<option value="1">1</option>\n<option value="2">2</option>\n<option value="3">3</option>\n<option value="4">4</option>\n<option value="5">5</option>\n<option value="6">6</option>\n<option value="7">7</option>\n<option value="8">8</option>\n<option value="9">9</option>\n<option value="10">10</option>\n<option value="11">11</option>\n<option value="12">12</option>\n<option value="13">13</option>\n<option value="14">14</option>\n<option value="15">15</option>\n<option value="16" selected="selected">16</option>\n<option value="17">17</option>\n<option value="18">18</option>\n<option value="19">19</option>\n<option value="20">20</option>\n<option value="21">21</option>\n<option value="22">22</option>\n<option value="23">23</option>\n<option value="24">24</option>\n<option value="25">25</option>\n<option value="26">26</option>\n<option value="27">27</option>\n<option value="28">28</option>\n<option value="29">29</option>\n<option value="30">30</option>\n<option value="31">31</option>\n)
     expected << "</select>\n"
 
-    assert_dom_equal expected, select_day(16, :prompt => true)
+    assert_dom_equal expected, select_day(16, prompt: true)
   end
 
   def test_select_day_with_custom_prompt
-    expected = %(<select id="date_day" name="date[day]">\n)
+    expected = %(<select id="date_day" name="date[day]">\n).dup
     expected << %(<option value="">Choose day</option>\n<option value="1">1</option>\n<option value="2">2</option>\n<option value="3">3</option>\n<option value="4">4</option>\n<option value="5">5</option>\n<option value="6">6</option>\n<option value="7">7</option>\n<option value="8">8</option>\n<option value="9">9</option>\n<option value="10">10</option>\n<option value="11">11</option>\n<option value="12">12</option>\n<option value="13">13</option>\n<option value="14">14</option>\n<option value="15">15</option>\n<option value="16" selected="selected">16</option>\n<option value="17">17</option>\n<option value="18">18</option>\n<option value="19">19</option>\n<option value="20">20</option>\n<option value="21">21</option>\n<option value="22">22</option>\n<option value="23">23</option>\n<option value="24">24</option>\n<option value="25">25</option>\n<option value="26">26</option>\n<option value="27">27</option>\n<option value="28">28</option>\n<option value="29">29</option>\n<option value="30">30</option>\n<option value="31">31</option>\n)
     expected << "</select>\n"
 
-    assert_dom_equal expected, select_day(16, :prompt => 'Choose day')
+    assert_dom_equal expected, select_day(16, prompt: "Choose day")
   end
 
   def test_select_day_with_generic_with_css_classes
-    expected = %(<select id="date_day" name="date[day]" class="day">\n)
+    expected = %(<select id="date_day" name="date[day]" class="day">\n).dup
     expected << %(<option value="1">1</option>\n<option value="2">2</option>\n<option value="3">3</option>\n<option value="4">4</option>\n<option value="5">5</option>\n<option value="6">6</option>\n<option value="7">7</option>\n<option value="8">8</option>\n<option value="9">9</option>\n<option value="10">10</option>\n<option value="11">11</option>\n<option value="12">12</option>\n<option value="13">13</option>\n<option value="14">14</option>\n<option value="15">15</option>\n<option value="16" selected="selected">16</option>\n<option value="17">17</option>\n<option value="18">18</option>\n<option value="19">19</option>\n<option value="20">20</option>\n<option value="21">21</option>\n<option value="22">22</option>\n<option value="23">23</option>\n<option value="24">24</option>\n<option value="25">25</option>\n<option value="26">26</option>\n<option value="27">27</option>\n<option value="28">28</option>\n<option value="29">29</option>\n<option value="30">30</option>\n<option value="31">31</option>\n)
     expected << "</select>\n"
 
@@ -264,15 +284,15 @@ class DateHelperTest < ActionView::TestCase
   end
 
   def test_select_day_with_custom_with_css_classes
-    expected = %(<select id="date_day" name="date[day]" class="my-day">\n)
+    expected = %(<select id="date_day" name="date[day]" class="my-day">\n).dup
     expected << %(<option value="1">1</option>\n<option value="2">2</option>\n<option value="3">3</option>\n<option value="4">4</option>\n<option value="5">5</option>\n<option value="6">6</option>\n<option value="7">7</option>\n<option value="8">8</option>\n<option value="9">9</option>\n<option value="10">10</option>\n<option value="11">11</option>\n<option value="12">12</option>\n<option value="13">13</option>\n<option value="14">14</option>\n<option value="15">15</option>\n<option value="16" selected="selected">16</option>\n<option value="17">17</option>\n<option value="18">18</option>\n<option value="19">19</option>\n<option value="20">20</option>\n<option value="21">21</option>\n<option value="22">22</option>\n<option value="23">23</option>\n<option value="24">24</option>\n<option value="25">25</option>\n<option value="26">26</option>\n<option value="27">27</option>\n<option value="28">28</option>\n<option value="29">29</option>\n<option value="30">30</option>\n<option value="31">31</option>\n)
     expected << "</select>\n"
 
-    assert_dom_equal expected, select_day(16, with_css_classes: { day: 'my-day' })
+    assert_dom_equal expected, select_day(16, with_css_classes: { day: "my-day" })
   end
 
   def test_select_month
-    expected = %(<select id="date_month" name="date[month]">\n)
+    expected = %(<select id="date_month" name="date[month]">\n).dup
     expected << %(<option value="1">January</option>\n<option value="2">February</option>\n<option value="3">March</option>\n<option value="4">April</option>\n<option value="5">May</option>\n<option value="6">June</option>\n<option value="7">July</option>\n<option value="8" selected="selected">August</option>\n<option value="9">September</option>\n<option value="10">October</option>\n<option value="11">November</option>\n<option value="12">December</option>\n)
     expected << "</select>\n"
 
@@ -281,151 +301,151 @@ class DateHelperTest < ActionView::TestCase
   end
 
   def test_select_month_with_two_digit_numbers
-    expected = %(<select id="date_month" name="date[month]">\n)
+    expected = %(<select id="date_month" name="date[month]">\n).dup
     expected << %(<option value="1">01</option>\n<option value="2">02</option>\n<option value="3">03</option>\n<option value="4">04</option>\n<option value="5">05</option>\n<option value="6">06</option>\n<option value="7">07</option>\n<option value="8" selected="selected">08</option>\n<option value="9">09</option>\n<option value="10">10</option>\n<option value="11">11</option>\n<option value="12">12</option>\n)
     expected << "</select>\n"
 
-    assert_dom_equal expected, select_month(Time.mktime(2011, 8, 16), :use_two_digit_numbers => true)
-    assert_dom_equal expected, select_month(8, :use_two_digit_numbers => true)
+    assert_dom_equal expected, select_month(Time.mktime(2011, 8, 16), use_two_digit_numbers: true)
+    assert_dom_equal expected, select_month(8, use_two_digit_numbers: true)
   end
 
   def test_select_month_with_disabled
-    expected = %(<select id="date_month" name="date[month]" disabled="disabled">\n)
+    expected = %(<select id="date_month" name="date[month]" disabled="disabled">\n).dup
     expected << %(<option value="1">January</option>\n<option value="2">February</option>\n<option value="3">March</option>\n<option value="4">April</option>\n<option value="5">May</option>\n<option value="6">June</option>\n<option value="7">July</option>\n<option value="8" selected="selected">August</option>\n<option value="9">September</option>\n<option value="10">October</option>\n<option value="11">November</option>\n<option value="12">December</option>\n)
     expected << "</select>\n"
 
-    assert_dom_equal expected, select_month(Time.mktime(2003, 8, 16), :disabled => true)
-    assert_dom_equal expected, select_month(8, :disabled => true)
+    assert_dom_equal expected, select_month(Time.mktime(2003, 8, 16), disabled: true)
+    assert_dom_equal expected, select_month(8, disabled: true)
   end
 
   def test_select_month_with_field_name_override
-    expected = %(<select id="date_mois" name="date[mois]">\n)
+    expected = %(<select id="date_mois" name="date[mois]">\n).dup
     expected << %(<option value="1">January</option>\n<option value="2">February</option>\n<option value="3">March</option>\n<option value="4">April</option>\n<option value="5">May</option>\n<option value="6">June</option>\n<option value="7">July</option>\n<option value="8" selected="selected">August</option>\n<option value="9">September</option>\n<option value="10">October</option>\n<option value="11">November</option>\n<option value="12">December</option>\n)
     expected << "</select>\n"
 
-    assert_dom_equal expected, select_month(Time.mktime(2003, 8, 16), :field_name => 'mois')
-    assert_dom_equal expected, select_month(8, :field_name => 'mois')
+    assert_dom_equal expected, select_month(Time.mktime(2003, 8, 16), field_name: "mois")
+    assert_dom_equal expected, select_month(8, field_name: "mois")
   end
 
   def test_select_month_with_blank
-    expected = %(<select id="date_month" name="date[month]">\n)
+    expected = %(<select id="date_month" name="date[month]">\n).dup
     expected << %(<option value=""></option>\n<option value="1">January</option>\n<option value="2">February</option>\n<option value="3">March</option>\n<option value="4">April</option>\n<option value="5">May</option>\n<option value="6">June</option>\n<option value="7">July</option>\n<option value="8" selected="selected">August</option>\n<option value="9">September</option>\n<option value="10">October</option>\n<option value="11">November</option>\n<option value="12">December</option>\n)
     expected << "</select>\n"
 
-    assert_dom_equal expected, select_month(Time.mktime(2003, 8, 16), :include_blank => true)
-    assert_dom_equal expected, select_month(8, :include_blank => true)
+    assert_dom_equal expected, select_month(Time.mktime(2003, 8, 16), include_blank: true)
+    assert_dom_equal expected, select_month(8, include_blank: true)
   end
 
   def test_select_month_nil_with_blank
-    expected = %(<select id="date_month" name="date[month]">\n)
+    expected = %(<select id="date_month" name="date[month]">\n).dup
     expected << %(<option value=""></option>\n<option value="1">January</option>\n<option value="2">February</option>\n<option value="3">March</option>\n<option value="4">April</option>\n<option value="5">May</option>\n<option value="6">June</option>\n<option value="7">July</option>\n<option value="8">August</option>\n<option value="9">September</option>\n<option value="10">October</option>\n<option value="11">November</option>\n<option value="12">December</option>\n)
     expected << "</select>\n"
 
-    assert_dom_equal expected, select_month(nil, :include_blank => true)
+    assert_dom_equal expected, select_month(nil, include_blank: true)
   end
 
   def test_select_month_with_numbers
-    expected = %(<select id="date_month" name="date[month]">\n)
+    expected = %(<select id="date_month" name="date[month]">\n).dup
     expected << %(<option value="1">1</option>\n<option value="2">2</option>\n<option value="3">3</option>\n<option value="4">4</option>\n<option value="5">5</option>\n<option value="6">6</option>\n<option value="7">7</option>\n<option value="8" selected="selected">8</option>\n<option value="9">9</option>\n<option value="10">10</option>\n<option value="11">11</option>\n<option value="12">12</option>\n)
     expected << "</select>\n"
 
-    assert_dom_equal expected, select_month(Time.mktime(2003, 8, 16), :use_month_numbers => true)
-    assert_dom_equal expected, select_month(8, :use_month_numbers => true)
+    assert_dom_equal expected, select_month(Time.mktime(2003, 8, 16), use_month_numbers: true)
+    assert_dom_equal expected, select_month(8, use_month_numbers: true)
   end
 
   def test_select_month_with_numbers_and_names
-    expected = %(<select id="date_month" name="date[month]">\n)
+    expected = %(<select id="date_month" name="date[month]">\n).dup
     expected << %(<option value="1">1 - January</option>\n<option value="2">2 - February</option>\n<option value="3">3 - March</option>\n<option value="4">4 - April</option>\n<option value="5">5 - May</option>\n<option value="6">6 - June</option>\n<option value="7">7 - July</option>\n<option value="8" selected="selected">8 - August</option>\n<option value="9">9 - September</option>\n<option value="10">10 - October</option>\n<option value="11">11 - November</option>\n<option value="12">12 - December</option>\n)
     expected << "</select>\n"
 
-    assert_dom_equal expected, select_month(Time.mktime(2003, 8, 16), :add_month_numbers => true)
-    assert_dom_equal expected, select_month(8, :add_month_numbers => true)
+    assert_dom_equal expected, select_month(Time.mktime(2003, 8, 16), add_month_numbers: true)
+    assert_dom_equal expected, select_month(8, add_month_numbers: true)
   end
 
   def test_select_month_with_format_string
-    expected = %(<select id="date_month" name="date[month]">\n)
+    expected = %(<select id="date_month" name="date[month]">\n).dup
     expected << %(<option value="1">January (01)</option>\n<option value="2">February (02)</option>\n<option value="3">March (03)</option>\n<option value="4">April (04)</option>\n<option value="5">May (05)</option>\n<option value="6">June (06)</option>\n<option value="7">July (07)</option>\n<option value="8" selected="selected">August (08)</option>\n<option value="9">September (09)</option>\n<option value="10">October (10)</option>\n<option value="11">November (11)</option>\n<option value="12">December (12)</option>\n)
     expected << "</select>\n"
 
-    format_string = '%{name} (%<number>02d)'
-    assert_dom_equal expected, select_month(Time.mktime(2003, 8, 16), :month_format_string => format_string)
-    assert_dom_equal expected, select_month(8, :month_format_string => format_string)
+    format_string = "%{name} (%<number>02d)"
+    assert_dom_equal expected, select_month(Time.mktime(2003, 8, 16), month_format_string: format_string)
+    assert_dom_equal expected, select_month(8, month_format_string: format_string)
   end
 
   def test_select_month_with_numbers_and_names_with_abbv
-    expected = %(<select id="date_month" name="date[month]">\n)
+    expected = %(<select id="date_month" name="date[month]">\n).dup
     expected << %(<option value="1">1 - Jan</option>\n<option value="2">2 - Feb</option>\n<option value="3">3 - Mar</option>\n<option value="4">4 - Apr</option>\n<option value="5">5 - May</option>\n<option value="6">6 - Jun</option>\n<option value="7">7 - Jul</option>\n<option value="8" selected="selected">8 - Aug</option>\n<option value="9">9 - Sep</option>\n<option value="10">10 - Oct</option>\n<option value="11">11 - Nov</option>\n<option value="12">12 - Dec</option>\n)
     expected << "</select>\n"
 
-    assert_dom_equal expected, select_month(Time.mktime(2003, 8, 16), :add_month_numbers => true, :use_short_month => true)
-    assert_dom_equal expected, select_month(8, :add_month_numbers => true, :use_short_month => true)
+    assert_dom_equal expected, select_month(Time.mktime(2003, 8, 16), add_month_numbers: true, use_short_month: true)
+    assert_dom_equal expected, select_month(8, add_month_numbers: true, use_short_month: true)
   end
 
   def test_select_month_with_abbv
-    expected = %(<select id="date_month" name="date[month]">\n)
+    expected = %(<select id="date_month" name="date[month]">\n).dup
     expected << %(<option value="1">Jan</option>\n<option value="2">Feb</option>\n<option value="3">Mar</option>\n<option value="4">Apr</option>\n<option value="5">May</option>\n<option value="6">Jun</option>\n<option value="7">Jul</option>\n<option value="8" selected="selected">Aug</option>\n<option value="9">Sep</option>\n<option value="10">Oct</option>\n<option value="11">Nov</option>\n<option value="12">Dec</option>\n)
     expected << "</select>\n"
 
-    assert_dom_equal expected, select_month(Time.mktime(2003, 8, 16), :use_short_month => true)
-    assert_dom_equal expected, select_month(8, :use_short_month => true)
+    assert_dom_equal expected, select_month(Time.mktime(2003, 8, 16), use_short_month: true)
+    assert_dom_equal expected, select_month(8, use_short_month: true)
   end
 
   def test_select_month_with_custom_names
     month_names = %w(nil Januar Februar Marts April Maj Juni Juli August September Oktober November December)
 
-    expected = %(<select id="date_month" name="date[month]">\n)
+    expected = %(<select id="date_month" name="date[month]">\n).dup
     1.upto(12) { |month| expected << %(<option value="#{month}"#{' selected="selected"' if month == 8}>#{month_names[month]}</option>\n) }
     expected << "</select>\n"
 
-    assert_dom_equal expected, select_month(Time.mktime(2003, 8, 16), :use_month_names => month_names)
-    assert_dom_equal expected, select_month(8, :use_month_names => month_names)
+    assert_dom_equal expected, select_month(Time.mktime(2003, 8, 16), use_month_names: month_names)
+    assert_dom_equal expected, select_month(8, use_month_names: month_names)
   end
 
   def test_select_month_with_zero_indexed_custom_names
     month_names = %w(Januar Februar Marts April Maj Juni Juli August September Oktober November December)
 
-    expected = %(<select id="date_month" name="date[month]">\n)
-    1.upto(12) { |month| expected << %(<option value="#{month}"#{' selected="selected"' if month == 8}>#{month_names[month-1]}</option>\n) }
+    expected = %(<select id="date_month" name="date[month]">\n).dup
+    1.upto(12) { |month| expected << %(<option value="#{month}"#{' selected="selected"' if month == 8}>#{month_names[month - 1]}</option>\n) }
     expected << "</select>\n"
 
-    assert_dom_equal expected, select_month(Time.mktime(2003, 8, 16), :use_month_names => month_names)
-    assert_dom_equal expected, select_month(8, :use_month_names => month_names)
+    assert_dom_equal expected, select_month(Time.mktime(2003, 8, 16), use_month_names: month_names)
+    assert_dom_equal expected, select_month(8, use_month_names: month_names)
   end
 
   def test_select_month_with_hidden
-    assert_dom_equal "<input type=\"hidden\" id=\"date_month\" name=\"date[month]\" value=\"8\" />\n", select_month(8, :use_hidden => true)
+    assert_dom_equal "<input type=\"hidden\" id=\"date_month\" name=\"date[month]\" value=\"8\" />\n", select_month(8, use_hidden: true)
   end
 
   def test_select_month_with_hidden_and_field_name
-    assert_dom_equal "<input type=\"hidden\" id=\"date_mois\" name=\"date[mois]\" value=\"8\" />\n", select_month(8, :use_hidden => true, :field_name => 'mois')
+    assert_dom_equal "<input type=\"hidden\" id=\"date_mois\" name=\"date[mois]\" value=\"8\" />\n", select_month(8, use_hidden: true, field_name: "mois")
   end
 
   def test_select_month_with_html_options
-    expected = %(<select id="date_month" name="date[month]" class="selector" accesskey="M">\n)
+    expected = %(<select id="date_month" name="date[month]" class="selector" accesskey="M">\n).dup
     expected << %(<option value="1">January</option>\n<option value="2">February</option>\n<option value="3">March</option>\n<option value="4">April</option>\n<option value="5">May</option>\n<option value="6">June</option>\n<option value="7">July</option>\n<option value="8" selected="selected">August</option>\n<option value="9">September</option>\n<option value="10">October</option>\n<option value="11">November</option>\n<option value="12">December</option>\n)
     expected << "</select>\n"
 
-    assert_dom_equal expected, select_month(Time.mktime(2003, 8, 16), {}, :class => 'selector', :accesskey => 'M')
+    assert_dom_equal expected, select_month(Time.mktime(2003, 8, 16), {}, { class: "selector", accesskey: "M" })
   end
 
   def test_select_month_with_default_prompt
-    expected = %(<select id="date_month" name="date[month]">\n)
+    expected = %(<select id="date_month" name="date[month]">\n).dup
     expected << %(<option value="">Month</option>\n<option value="1">January</option>\n<option value="2">February</option>\n<option value="3">March</option>\n<option value="4">April</option>\n<option value="5">May</option>\n<option value="6">June</option>\n<option value="7">July</option>\n<option value="8" selected="selected">August</option>\n<option value="9">September</option>\n<option value="10">October</option>\n<option value="11">November</option>\n<option value="12">December</option>\n)
     expected << "</select>\n"
 
-    assert_dom_equal expected, select_month(8, :prompt => true)
+    assert_dom_equal expected, select_month(8, prompt: true)
   end
 
   def test_select_month_with_custom_prompt
-    expected = %(<select id="date_month" name="date[month]">\n)
+    expected = %(<select id="date_month" name="date[month]">\n).dup
     expected << %(<option value="">Choose month</option>\n<option value="1">January</option>\n<option value="2">February</option>\n<option value="3">March</option>\n<option value="4">April</option>\n<option value="5">May</option>\n<option value="6">June</option>\n<option value="7">July</option>\n<option value="8" selected="selected">August</option>\n<option value="9">September</option>\n<option value="10">October</option>\n<option value="11">November</option>\n<option value="12">December</option>\n)
     expected << "</select>\n"
 
-    assert_dom_equal expected, select_month(8, :prompt => 'Choose month')
+    assert_dom_equal expected, select_month(8, prompt: "Choose month")
   end
 
   def test_select_month_with_generic_with_css_classes
-    expected = %(<select id="date_month" name="date[month]" class="month">\n)
+    expected = %(<select id="date_month" name="date[month]" class="month">\n).dup
     expected << %(<option value="1">January</option>\n<option value="2">February</option>\n<option value="3">March</option>\n<option value="4">April</option>\n<option value="5">May</option>\n<option value="6">June</option>\n<option value="7">July</option>\n<option value="8" selected="selected">August</option>\n<option value="9">September</option>\n<option value="10">October</option>\n<option value="11">November</option>\n<option value="12">December</option>\n)
     expected << "</select>\n"
 
@@ -433,94 +453,94 @@ class DateHelperTest < ActionView::TestCase
   end
 
   def test_select_month_with_custom_with_css_classes
-    expected = %(<select id="date_month" name="date[month]" class="my-month">\n)
+    expected = %(<select id="date_month" name="date[month]" class="my-month">\n).dup
     expected << %(<option value="1">January</option>\n<option value="2">February</option>\n<option value="3">March</option>\n<option value="4">April</option>\n<option value="5">May</option>\n<option value="6">June</option>\n<option value="7">July</option>\n<option value="8" selected="selected">August</option>\n<option value="9">September</option>\n<option value="10">October</option>\n<option value="11">November</option>\n<option value="12">December</option>\n)
     expected << "</select>\n"
 
-    assert_dom_equal expected, select_month(8, with_css_classes: { month: 'my-month' })
+    assert_dom_equal expected, select_month(8, with_css_classes: { month: "my-month" })
   end
 
   def test_select_year
-    expected = %(<select id="date_year" name="date[year]">\n)
+    expected = %(<select id="date_year" name="date[year]">\n).dup
     expected << %(<option value="2003" selected="selected">2003</option>\n<option value="2004">2004</option>\n<option value="2005">2005</option>\n)
     expected << "</select>\n"
 
-    assert_dom_equal expected, select_year(Time.mktime(2003, 8, 16), :start_year => 2003, :end_year => 2005)
-    assert_dom_equal expected, select_year(2003, :start_year => 2003, :end_year => 2005)
+    assert_dom_equal expected, select_year(Time.mktime(2003, 8, 16), start_year: 2003, end_year: 2005)
+    assert_dom_equal expected, select_year(2003, start_year: 2003, end_year: 2005)
   end
 
   def test_select_year_with_disabled
-    expected = %(<select id="date_year" name="date[year]" disabled="disabled">\n)
+    expected = %(<select id="date_year" name="date[year]" disabled="disabled">\n).dup
     expected << %(<option value="2003" selected="selected">2003</option>\n<option value="2004">2004</option>\n<option value="2005">2005</option>\n)
     expected << "</select>\n"
 
-    assert_dom_equal expected, select_year(Time.mktime(2003, 8, 16), :disabled => true, :start_year => 2003, :end_year => 2005)
-    assert_dom_equal expected, select_year(2003, :disabled => true, :start_year => 2003, :end_year => 2005)
+    assert_dom_equal expected, select_year(Time.mktime(2003, 8, 16), disabled: true, start_year: 2003, end_year: 2005)
+    assert_dom_equal expected, select_year(2003, disabled: true, start_year: 2003, end_year: 2005)
   end
 
   def test_select_year_with_field_name_override
-    expected = %(<select id="date_annee" name="date[annee]">\n)
+    expected = %(<select id="date_annee" name="date[annee]">\n).dup
     expected << %(<option value="2003" selected="selected">2003</option>\n<option value="2004">2004</option>\n<option value="2005">2005</option>\n)
     expected << "</select>\n"
 
-    assert_dom_equal expected, select_year(Time.mktime(2003, 8, 16), :start_year => 2003, :end_year => 2005, :field_name => 'annee')
-    assert_dom_equal expected, select_year(2003, :start_year => 2003, :end_year => 2005, :field_name => 'annee')
+    assert_dom_equal expected, select_year(Time.mktime(2003, 8, 16), start_year: 2003, end_year: 2005, field_name: "annee")
+    assert_dom_equal expected, select_year(2003, start_year: 2003, end_year: 2005, field_name: "annee")
   end
 
   def test_select_year_with_type_discarding
-    expected = %(<select id="date_year" name="date_year">\n)
+    expected = %(<select id="date_year" name="date_year">\n).dup
     expected << %(<option value="2003" selected="selected">2003</option>\n<option value="2004">2004</option>\n<option value="2005">2005</option>\n)
     expected << "</select>\n"
 
     assert_dom_equal expected, select_year(
-      Time.mktime(2003, 8, 16), :prefix => "date_year", :discard_type => true, :start_year => 2003, :end_year => 2005)
+      Time.mktime(2003, 8, 16), prefix: "date_year", discard_type: true, start_year: 2003, end_year: 2005)
     assert_dom_equal expected, select_year(
-      2003, :prefix => "date_year", :discard_type => true, :start_year => 2003, :end_year => 2005)
+      2003, prefix: "date_year", discard_type: true, start_year: 2003, end_year: 2005)
   end
 
   def test_select_year_descending
-    expected = %(<select id="date_year" name="date[year]">\n)
+    expected = %(<select id="date_year" name="date[year]">\n).dup
     expected << %(<option value="2005" selected="selected">2005</option>\n<option value="2004">2004</option>\n<option value="2003">2003</option>\n)
     expected << "</select>\n"
 
-    assert_dom_equal expected, select_year(Time.mktime(2005, 8, 16), :start_year => 2005, :end_year => 2003)
-    assert_dom_equal expected, select_year(2005, :start_year => 2005, :end_year => 2003)
+    assert_dom_equal expected, select_year(Time.mktime(2005, 8, 16), start_year: 2005, end_year: 2003)
+    assert_dom_equal expected, select_year(2005, start_year: 2005, end_year: 2003)
   end
 
   def test_select_year_with_hidden
-    assert_dom_equal "<input type=\"hidden\" id=\"date_year\" name=\"date[year]\" value=\"2007\" />\n", select_year(2007, :use_hidden => true)
+    assert_dom_equal "<input type=\"hidden\" id=\"date_year\" name=\"date[year]\" value=\"2007\" />\n", select_year(2007, use_hidden: true)
   end
 
   def test_select_year_with_hidden_and_field_name
-    assert_dom_equal "<input type=\"hidden\" id=\"date_anno\" name=\"date[anno]\" value=\"2007\" />\n", select_year(2007, :use_hidden => true, :field_name => 'anno')
+    assert_dom_equal "<input type=\"hidden\" id=\"date_anno\" name=\"date[anno]\" value=\"2007\" />\n", select_year(2007, use_hidden: true, field_name: "anno")
   end
 
   def test_select_year_with_html_options
-    expected = %(<select id="date_year" name="date[year]" class="selector" accesskey="M">\n)
+    expected = %(<select id="date_year" name="date[year]" class="selector" accesskey="M">\n).dup
     expected << %(<option value="2003" selected="selected">2003</option>\n<option value="2004">2004</option>\n<option value="2005">2005</option>\n)
     expected << "</select>\n"
 
-    assert_dom_equal expected, select_year(Time.mktime(2003, 8, 16), {:start_year => 2003, :end_year => 2005}, :class => 'selector', :accesskey => 'M')
+    assert_dom_equal expected, select_year(Time.mktime(2003, 8, 16), { start_year: 2003, end_year: 2005 }, { class: "selector", accesskey: "M" })
   end
 
   def test_select_year_with_default_prompt
-    expected = %(<select id="date_year" name="date[year]">\n)
+    expected = %(<select id="date_year" name="date[year]">\n).dup
     expected << %(<option value="">Year</option>\n<option value="2003">2003</option>\n<option value="2004">2004</option>\n<option value="2005">2005</option>\n)
     expected << "</select>\n"
 
-    assert_dom_equal expected, select_year(nil, :start_year => 2003, :end_year => 2005, :prompt => true)
+    assert_dom_equal expected, select_year(nil, start_year: 2003, end_year: 2005, prompt: true)
   end
 
   def test_select_year_with_custom_prompt
-    expected = %(<select id="date_year" name="date[year]">\n)
+    expected = %(<select id="date_year" name="date[year]">\n).dup
     expected << %(<option value="">Choose year</option>\n<option value="2003">2003</option>\n<option value="2004">2004</option>\n<option value="2005">2005</option>\n)
     expected << "</select>\n"
 
-    assert_dom_equal expected, select_year(nil, :start_year => 2003, :end_year => 2005, :prompt => 'Choose year')
+    assert_dom_equal expected, select_year(nil, start_year: 2003, end_year: 2005, prompt: "Choose year")
   end
 
   def test_select_year_with_generic_with_css_classes
-    expected = %(<select id="date_year" name="date[year]" class="year">\n)
+    expected = %(<select id="date_year" name="date[year]" class="year">\n).dup
     expected << %(<option value="2003">2003</option>\n<option value="2004">2004</option>\n<option value="2005">2005</option>\n)
     expected << "</select>\n"
 
@@ -528,15 +548,22 @@ class DateHelperTest < ActionView::TestCase
   end
 
   def test_select_year_with_custom_with_css_classes
-    expected = %(<select id="date_year" name="date[year]" class="my-year">\n)
+    expected = %(<select id="date_year" name="date[year]" class="my-year">\n).dup
     expected << %(<option value="2003">2003</option>\n<option value="2004">2004</option>\n<option value="2005">2005</option>\n)
     expected << "</select>\n"
 
-    assert_dom_equal expected, select_year(nil, start_year: 2003, end_year: 2005, with_css_classes: { year: 'my-year' })
+    assert_dom_equal expected, select_year(nil, start_year: 2003, end_year: 2005, with_css_classes: { year: "my-year" })
+  end
+
+  def test_select_year_with_position
+    expected = %(<select id="date_year_1i" name="date[year(1i)]">\n).dup
+    expected << %(<option value="2003">2003</option>\n<option value="2004">2004</option>\n<option value="2005">2005</option>\n)
+    expected << "</select>\n"
+    assert_dom_equal expected, select_year(Date.current, include_position: true,  start_year: 2003, end_year: 2005)
   end
 
   def test_select_hour
-    expected = %(<select id="date_hour" name="date[hour]">\n)
+    expected = %(<select id="date_hour" name="date[hour]">\n).dup
     expected << %(<option value="00">00</option>\n<option value="01">01</option>\n<option value="02">02</option>\n<option value="03">03</option>\n<option value="04">04</option>\n<option value="05">05</option>\n<option value="06">06</option>\n<option value="07">07</option>\n<option value="08" selected="selected">08</option>\n<option value="09">09</option>\n<option value="10">10</option>\n<option value="11">11</option>\n<option value="12">12</option>\n<option value="13">13</option>\n<option value="14">14</option>\n<option value="15">15</option>\n<option value="16">16</option>\n<option value="17">17</option>\n<option value="18">18</option>\n<option value="19">19</option>\n<option value="20">20</option>\n<option value="21">21</option>\n<option value="22">22</option>\n<option value="23">23</option>\n)
     expected << "</select>\n"
 
@@ -544,71 +571,71 @@ class DateHelperTest < ActionView::TestCase
   end
 
   def test_select_hour_with_ampm
-    expected = %(<select id="date_hour" name="date[hour]">\n)
+    expected = %(<select id="date_hour" name="date[hour]">\n).dup
     expected << %(<option value="00">12 AM</option>\n<option value="01">01 AM</option>\n<option value="02">02 AM</option>\n<option value="03">03 AM</option>\n<option value="04">04 AM</option>\n<option value="05">05 AM</option>\n<option value="06">06 AM</option>\n<option value="07">07 AM</option>\n<option value="08" selected="selected">08 AM</option>\n<option value="09">09 AM</option>\n<option value="10">10 AM</option>\n<option value="11">11 AM</option>\n<option value="12">12 PM</option>\n<option value="13">01 PM</option>\n<option value="14">02 PM</option>\n<option value="15">03 PM</option>\n<option value="16">04 PM</option>\n<option value="17">05 PM</option>\n<option value="18">06 PM</option>\n<option value="19">07 PM</option>\n<option value="20">08 PM</option>\n<option value="21">09 PM</option>\n<option value="22">10 PM</option>\n<option value="23">11 PM</option>\n)
     expected << "</select>\n"
 
-    assert_dom_equal expected, select_hour(Time.mktime(2003, 8, 16, 8, 4, 18), :ampm => true)
+    assert_dom_equal expected, select_hour(Time.mktime(2003, 8, 16, 8, 4, 18), ampm: true)
   end
 
   def test_select_hour_with_disabled
-    expected = %(<select id="date_hour" name="date[hour]" disabled="disabled">\n)
+    expected = %(<select id="date_hour" name="date[hour]" disabled="disabled">\n).dup
     expected << %(<option value="00">00</option>\n<option value="01">01</option>\n<option value="02">02</option>\n<option value="03">03</option>\n<option value="04">04</option>\n<option value="05">05</option>\n<option value="06">06</option>\n<option value="07">07</option>\n<option value="08" selected="selected">08</option>\n<option value="09">09</option>\n<option value="10">10</option>\n<option value="11">11</option>\n<option value="12">12</option>\n<option value="13">13</option>\n<option value="14">14</option>\n<option value="15">15</option>\n<option value="16">16</option>\n<option value="17">17</option>\n<option value="18">18</option>\n<option value="19">19</option>\n<option value="20">20</option>\n<option value="21">21</option>\n<option value="22">22</option>\n<option value="23">23</option>\n)
     expected << "</select>\n"
 
-    assert_dom_equal expected, select_hour(Time.mktime(2003, 8, 16, 8, 4, 18), :disabled => true)
+    assert_dom_equal expected, select_hour(Time.mktime(2003, 8, 16, 8, 4, 18), disabled: true)
   end
 
   def test_select_hour_with_field_name_override
-    expected = %(<select id="date_heure" name="date[heure]">\n)
+    expected = %(<select id="date_heure" name="date[heure]">\n).dup
     expected << %(<option value="00">00</option>\n<option value="01">01</option>\n<option value="02">02</option>\n<option value="03">03</option>\n<option value="04">04</option>\n<option value="05">05</option>\n<option value="06">06</option>\n<option value="07">07</option>\n<option value="08" selected="selected">08</option>\n<option value="09">09</option>\n<option value="10">10</option>\n<option value="11">11</option>\n<option value="12">12</option>\n<option value="13">13</option>\n<option value="14">14</option>\n<option value="15">15</option>\n<option value="16">16</option>\n<option value="17">17</option>\n<option value="18">18</option>\n<option value="19">19</option>\n<option value="20">20</option>\n<option value="21">21</option>\n<option value="22">22</option>\n<option value="23">23</option>\n)
     expected << "</select>\n"
 
-    assert_dom_equal expected, select_hour(Time.mktime(2003, 8, 16, 8, 4, 18), :field_name => 'heure')
+    assert_dom_equal expected, select_hour(Time.mktime(2003, 8, 16, 8, 4, 18), field_name: "heure")
   end
 
   def test_select_hour_with_blank
-    expected = %(<select id="date_hour" name="date[hour]">\n)
+    expected = %(<select id="date_hour" name="date[hour]">\n).dup
     expected << %(<option value=""></option>\n<option value="00">00</option>\n<option value="01">01</option>\n<option value="02">02</option>\n<option value="03">03</option>\n<option value="04">04</option>\n<option value="05">05</option>\n<option value="06">06</option>\n<option value="07">07</option>\n<option value="08" selected="selected">08</option>\n<option value="09">09</option>\n<option value="10">10</option>\n<option value="11">11</option>\n<option value="12">12</option>\n<option value="13">13</option>\n<option value="14">14</option>\n<option value="15">15</option>\n<option value="16">16</option>\n<option value="17">17</option>\n<option value="18">18</option>\n<option value="19">19</option>\n<option value="20">20</option>\n<option value="21">21</option>\n<option value="22">22</option>\n<option value="23">23</option>\n)
     expected << "</select>\n"
 
-    assert_dom_equal expected, select_hour(Time.mktime(2003, 8, 16, 8, 4, 18), :include_blank => true)
+    assert_dom_equal expected, select_hour(Time.mktime(2003, 8, 16, 8, 4, 18), include_blank: true)
   end
 
   def test_select_hour_nil_with_blank
-    expected = %(<select id="date_hour" name="date[hour]">\n)
+    expected = %(<select id="date_hour" name="date[hour]">\n).dup
     expected << %(<option value=""></option>\n<option value="00">00</option>\n<option value="01">01</option>\n<option value="02">02</option>\n<option value="03">03</option>\n<option value="04">04</option>\n<option value="05">05</option>\n<option value="06">06</option>\n<option value="07">07</option>\n<option value="08">08</option>\n<option value="09">09</option>\n<option value="10">10</option>\n<option value="11">11</option>\n<option value="12">12</option>\n<option value="13">13</option>\n<option value="14">14</option>\n<option value="15">15</option>\n<option value="16">16</option>\n<option value="17">17</option>\n<option value="18">18</option>\n<option value="19">19</option>\n<option value="20">20</option>\n<option value="21">21</option>\n<option value="22">22</option>\n<option value="23">23</option>\n)
     expected << "</select>\n"
 
-    assert_dom_equal expected, select_hour(nil, :include_blank => true)
+    assert_dom_equal expected, select_hour(nil, include_blank: true)
   end
 
   def test_select_hour_with_html_options
-    expected = %(<select id="date_hour" name="date[hour]" class="selector" accesskey="M">\n)
+    expected = %(<select id="date_hour" name="date[hour]" class="selector" accesskey="M">\n).dup
     expected << %(<option value="00">00</option>\n<option value="01">01</option>\n<option value="02">02</option>\n<option value="03">03</option>\n<option value="04">04</option>\n<option value="05">05</option>\n<option value="06">06</option>\n<option value="07">07</option>\n<option value="08" selected="selected">08</option>\n<option value="09">09</option>\n<option value="10">10</option>\n<option value="11">11</option>\n<option value="12">12</option>\n<option value="13">13</option>\n<option value="14">14</option>\n<option value="15">15</option>\n<option value="16">16</option>\n<option value="17">17</option>\n<option value="18">18</option>\n<option value="19">19</option>\n<option value="20">20</option>\n<option value="21">21</option>\n<option value="22">22</option>\n<option value="23">23</option>\n)
     expected << "</select>\n"
 
-    assert_dom_equal expected, select_hour(Time.mktime(2003, 8, 16, 8, 4, 18), {}, :class => 'selector', :accesskey => 'M')
+    assert_dom_equal expected, select_hour(Time.mktime(2003, 8, 16, 8, 4, 18), {}, { class: "selector", accesskey: "M" })
   end
 
   def test_select_hour_with_default_prompt
-    expected = %(<select id="date_hour" name="date[hour]">\n)
+    expected = %(<select id="date_hour" name="date[hour]">\n).dup
     expected << %(<option value="">Hour</option>\n<option value="00">00</option>\n<option value="01">01</option>\n<option value="02">02</option>\n<option value="03">03</option>\n<option value="04">04</option>\n<option value="05">05</option>\n<option value="06">06</option>\n<option value="07">07</option>\n<option value="08" selected="selected">08</option>\n<option value="09">09</option>\n<option value="10">10</option>\n<option value="11">11</option>\n<option value="12">12</option>\n<option value="13">13</option>\n<option value="14">14</option>\n<option value="15">15</option>\n<option value="16">16</option>\n<option value="17">17</option>\n<option value="18">18</option>\n<option value="19">19</option>\n<option value="20">20</option>\n<option value="21">21</option>\n<option value="22">22</option>\n<option value="23">23</option>\n)
     expected << "</select>\n"
 
-    assert_dom_equal expected, select_hour(Time.mktime(2003, 8, 16, 8, 4, 18), :prompt => true)
+    assert_dom_equal expected, select_hour(Time.mktime(2003, 8, 16, 8, 4, 18), prompt: true)
   end
 
   def test_select_hour_with_custom_prompt
-    expected = %(<select id="date_hour" name="date[hour]">\n)
+    expected = %(<select id="date_hour" name="date[hour]">\n).dup
     expected << %(<option value="">Choose hour</option>\n<option value="00">00</option>\n<option value="01">01</option>\n<option value="02">02</option>\n<option value="03">03</option>\n<option value="04">04</option>\n<option value="05">05</option>\n<option value="06">06</option>\n<option value="07">07</option>\n<option value="08" selected="selected">08</option>\n<option value="09">09</option>\n<option value="10">10</option>\n<option value="11">11</option>\n<option value="12">12</option>\n<option value="13">13</option>\n<option value="14">14</option>\n<option value="15">15</option>\n<option value="16">16</option>\n<option value="17">17</option>\n<option value="18">18</option>\n<option value="19">19</option>\n<option value="20">20</option>\n<option value="21">21</option>\n<option value="22">22</option>\n<option value="23">23</option>\n)
     expected << "</select>\n"
 
-    assert_dom_equal expected, select_hour(Time.mktime(2003, 8, 16, 8, 4, 18), :prompt => 'Choose hour')
+    assert_dom_equal expected, select_hour(Time.mktime(2003, 8, 16, 8, 4, 18), prompt: "Choose hour")
   end
 
   def test_select_hour_with_generic_with_css_classes
-    expected = %(<select id="date_hour" name="date[hour]" class="hour">\n)
+    expected = %(<select id="date_hour" name="date[hour]" class="hour">\n).dup
     expected << %(<option value="00">00</option>\n<option value="01">01</option>\n<option value="02">02</option>\n<option value="03">03</option>\n<option value="04">04</option>\n<option value="05">05</option>\n<option value="06">06</option>\n<option value="07">07</option>\n<option value="08" selected="selected">08</option>\n<option value="09">09</option>\n<option value="10">10</option>\n<option value="11">11</option>\n<option value="12">12</option>\n<option value="13">13</option>\n<option value="14">14</option>\n<option value="15">15</option>\n<option value="16">16</option>\n<option value="17">17</option>\n<option value="18">18</option>\n<option value="19">19</option>\n<option value="20">20</option>\n<option value="21">21</option>\n<option value="22">22</option>\n<option value="23">23</option>\n)
     expected << "</select>\n"
 
@@ -616,15 +643,15 @@ class DateHelperTest < ActionView::TestCase
   end
 
   def test_select_hour_with_custom_with_css_classes
-    expected = %(<select id="date_hour" name="date[hour]" class="my-hour">\n)
+    expected = %(<select id="date_hour" name="date[hour]" class="my-hour">\n).dup
     expected << %(<option value="00">00</option>\n<option value="01">01</option>\n<option value="02">02</option>\n<option value="03">03</option>\n<option value="04">04</option>\n<option value="05">05</option>\n<option value="06">06</option>\n<option value="07">07</option>\n<option value="08" selected="selected">08</option>\n<option value="09">09</option>\n<option value="10">10</option>\n<option value="11">11</option>\n<option value="12">12</option>\n<option value="13">13</option>\n<option value="14">14</option>\n<option value="15">15</option>\n<option value="16">16</option>\n<option value="17">17</option>\n<option value="18">18</option>\n<option value="19">19</option>\n<option value="20">20</option>\n<option value="21">21</option>\n<option value="22">22</option>\n<option value="23">23</option>\n)
     expected << "</select>\n"
 
-    assert_dom_equal expected, select_hour(Time.mktime(2003, 8, 16, 8, 4, 18), with_css_classes: { hour: 'my-hour' })
+    assert_dom_equal expected, select_hour(Time.mktime(2003, 8, 16, 8, 4, 18), with_css_classes: { hour: "my-hour" })
   end
 
   def test_select_minute
-    expected = %(<select id="date_minute" name="date[minute]">\n)
+    expected = %(<select id="date_minute" name="date[minute]">\n).dup
     expected << %(<option value="00">00</option>\n<option value="01">01</option>\n<option value="02">02</option>\n<option value="03">03</option>\n<option value="04" selected="selected">04</option>\n<option value="05">05</option>\n<option value="06">06</option>\n<option value="07">07</option>\n<option value="08">08</option>\n<option value="09">09</option>\n<option value="10">10</option>\n<option value="11">11</option>\n<option value="12">12</option>\n<option value="13">13</option>\n<option value="14">14</option>\n<option value="15">15</option>\n<option value="16">16</option>\n<option value="17">17</option>\n<option value="18">18</option>\n<option value="19">19</option>\n<option value="20">20</option>\n<option value="21">21</option>\n<option value="22">22</option>\n<option value="23">23</option>\n<option value="24">24</option>\n<option value="25">25</option>\n<option value="26">26</option>\n<option value="27">27</option>\n<option value="28">28</option>\n<option value="29">29</option>\n<option value="30">30</option>\n<option value="31">31</option>\n<option value="32">32</option>\n<option value="33">33</option>\n<option value="34">34</option>\n<option value="35">35</option>\n<option value="36">36</option>\n<option value="37">37</option>\n<option value="38">38</option>\n<option value="39">39</option>\n<option value="40">40</option>\n<option value="41">41</option>\n<option value="42">42</option>\n<option value="43">43</option>\n<option value="44">44</option>\n<option value="45">45</option>\n<option value="46">46</option>\n<option value="47">47</option>\n<option value="48">48</option>\n<option value="49">49</option>\n<option value="50">50</option>\n<option value="51">51</option>\n<option value="52">52</option>\n<option value="53">53</option>\n<option value="54">54</option>\n<option value="55">55</option>\n<option value="56">56</option>\n<option value="57">57</option>\n<option value="58">58</option>\n<option value="59">59</option>\n)
     expected << "</select>\n"
 
@@ -632,87 +659,87 @@ class DateHelperTest < ActionView::TestCase
   end
 
   def test_select_minute_with_disabled
-    expected = %(<select id="date_minute" name="date[minute]" disabled="disabled">\n)
+    expected = %(<select id="date_minute" name="date[minute]" disabled="disabled">\n).dup
     expected << %(<option value="00">00</option>\n<option value="01">01</option>\n<option value="02">02</option>\n<option value="03">03</option>\n<option value="04" selected="selected">04</option>\n<option value="05">05</option>\n<option value="06">06</option>\n<option value="07">07</option>\n<option value="08">08</option>\n<option value="09">09</option>\n<option value="10">10</option>\n<option value="11">11</option>\n<option value="12">12</option>\n<option value="13">13</option>\n<option value="14">14</option>\n<option value="15">15</option>\n<option value="16">16</option>\n<option value="17">17</option>\n<option value="18">18</option>\n<option value="19">19</option>\n<option value="20">20</option>\n<option value="21">21</option>\n<option value="22">22</option>\n<option value="23">23</option>\n<option value="24">24</option>\n<option value="25">25</option>\n<option value="26">26</option>\n<option value="27">27</option>\n<option value="28">28</option>\n<option value="29">29</option>\n<option value="30">30</option>\n<option value="31">31</option>\n<option value="32">32</option>\n<option value="33">33</option>\n<option value="34">34</option>\n<option value="35">35</option>\n<option value="36">36</option>\n<option value="37">37</option>\n<option value="38">38</option>\n<option value="39">39</option>\n<option value="40">40</option>\n<option value="41">41</option>\n<option value="42">42</option>\n<option value="43">43</option>\n<option value="44">44</option>\n<option value="45">45</option>\n<option value="46">46</option>\n<option value="47">47</option>\n<option value="48">48</option>\n<option value="49">49</option>\n<option value="50">50</option>\n<option value="51">51</option>\n<option value="52">52</option>\n<option value="53">53</option>\n<option value="54">54</option>\n<option value="55">55</option>\n<option value="56">56</option>\n<option value="57">57</option>\n<option value="58">58</option>\n<option value="59">59</option>\n)
     expected << "</select>\n"
 
-    assert_dom_equal expected, select_minute(Time.mktime(2003, 8, 16, 8, 4, 18), :disabled => true)
+    assert_dom_equal expected, select_minute(Time.mktime(2003, 8, 16, 8, 4, 18), disabled: true)
   end
 
   def test_select_minute_with_field_name_override
-    expected = %(<select id="date_minuto" name="date[minuto]">\n)
+    expected = %(<select id="date_minuto" name="date[minuto]">\n).dup
     expected << %(<option value="00">00</option>\n<option value="01">01</option>\n<option value="02">02</option>\n<option value="03">03</option>\n<option value="04" selected="selected">04</option>\n<option value="05">05</option>\n<option value="06">06</option>\n<option value="07">07</option>\n<option value="08">08</option>\n<option value="09">09</option>\n<option value="10">10</option>\n<option value="11">11</option>\n<option value="12">12</option>\n<option value="13">13</option>\n<option value="14">14</option>\n<option value="15">15</option>\n<option value="16">16</option>\n<option value="17">17</option>\n<option value="18">18</option>\n<option value="19">19</option>\n<option value="20">20</option>\n<option value="21">21</option>\n<option value="22">22</option>\n<option value="23">23</option>\n<option value="24">24</option>\n<option value="25">25</option>\n<option value="26">26</option>\n<option value="27">27</option>\n<option value="28">28</option>\n<option value="29">29</option>\n<option value="30">30</option>\n<option value="31">31</option>\n<option value="32">32</option>\n<option value="33">33</option>\n<option value="34">34</option>\n<option value="35">35</option>\n<option value="36">36</option>\n<option value="37">37</option>\n<option value="38">38</option>\n<option value="39">39</option>\n<option value="40">40</option>\n<option value="41">41</option>\n<option value="42">42</option>\n<option value="43">43</option>\n<option value="44">44</option>\n<option value="45">45</option>\n<option value="46">46</option>\n<option value="47">47</option>\n<option value="48">48</option>\n<option value="49">49</option>\n<option value="50">50</option>\n<option value="51">51</option>\n<option value="52">52</option>\n<option value="53">53</option>\n<option value="54">54</option>\n<option value="55">55</option>\n<option value="56">56</option>\n<option value="57">57</option>\n<option value="58">58</option>\n<option value="59">59</option>\n)
     expected << "</select>\n"
 
-    assert_dom_equal expected, select_minute(Time.mktime(2003, 8, 16, 8, 4, 18), :field_name => 'minuto')
+    assert_dom_equal expected, select_minute(Time.mktime(2003, 8, 16, 8, 4, 18), field_name: "minuto")
   end
 
   def test_select_minute_with_blank
-    expected = %(<select id="date_minute" name="date[minute]">\n)
+    expected = %(<select id="date_minute" name="date[minute]">\n).dup
     expected << %(<option value=""></option>\n<option value="00">00</option>\n<option value="01">01</option>\n<option value="02">02</option>\n<option value="03">03</option>\n<option value="04" selected="selected">04</option>\n<option value="05">05</option>\n<option value="06">06</option>\n<option value="07">07</option>\n<option value="08">08</option>\n<option value="09">09</option>\n<option value="10">10</option>\n<option value="11">11</option>\n<option value="12">12</option>\n<option value="13">13</option>\n<option value="14">14</option>\n<option value="15">15</option>\n<option value="16">16</option>\n<option value="17">17</option>\n<option value="18">18</option>\n<option value="19">19</option>\n<option value="20">20</option>\n<option value="21">21</option>\n<option value="22">22</option>\n<option value="23">23</option>\n<option value="24">24</option>\n<option value="25">25</option>\n<option value="26">26</option>\n<option value="27">27</option>\n<option value="28">28</option>\n<option value="29">29</option>\n<option value="30">30</option>\n<option value="31">31</option>\n<option value="32">32</option>\n<option value="33">33</option>\n<option value="34">34</option>\n<option value="35">35</option>\n<option value="36">36</option>\n<option value="37">37</option>\n<option value="38">38</option>\n<option value="39">39</option>\n<option value="40">40</option>\n<option value="41">41</option>\n<option value="42">42</option>\n<option value="43">43</option>\n<option value="44">44</option>\n<option value="45">45</option>\n<option value="46">46</option>\n<option value="47">47</option>\n<option value="48">48</option>\n<option value="49">49</option>\n<option value="50">50</option>\n<option value="51">51</option>\n<option value="52">52</option>\n<option value="53">53</option>\n<option value="54">54</option>\n<option value="55">55</option>\n<option value="56">56</option>\n<option value="57">57</option>\n<option value="58">58</option>\n<option value="59">59</option>\n)
     expected << "</select>\n"
 
-    assert_dom_equal expected, select_minute(Time.mktime(2003, 8, 16, 8, 4, 18), :include_blank => true)
+    assert_dom_equal expected, select_minute(Time.mktime(2003, 8, 16, 8, 4, 18), include_blank: true)
   end
 
   def test_select_minute_with_blank_and_step
-    expected = %(<select id="date_minute" name="date[minute]">\n)
+    expected = %(<select id="date_minute" name="date[minute]">\n).dup
     expected << %(<option value=""></option>\n<option value="00">00</option>\n<option value="15">15</option>\n<option value="30">30</option>\n<option value="45">45</option>\n)
     expected << "</select>\n"
 
-    assert_dom_equal expected, select_minute(Time.mktime(2003, 8, 16, 8, 4, 18), { :include_blank => true , :minute_step => 15 })
+    assert_dom_equal expected, select_minute(Time.mktime(2003, 8, 16, 8, 4, 18), include_blank: true, minute_step: 15)
   end
 
   def test_select_minute_nil_with_blank
-    expected = %(<select id="date_minute" name="date[minute]">\n)
+    expected = %(<select id="date_minute" name="date[minute]">\n).dup
     expected << %(<option value=""></option>\n<option value="00">00</option>\n<option value="01">01</option>\n<option value="02">02</option>\n<option value="03">03</option>\n<option value="04">04</option>\n<option value="05">05</option>\n<option value="06">06</option>\n<option value="07">07</option>\n<option value="08">08</option>\n<option value="09">09</option>\n<option value="10">10</option>\n<option value="11">11</option>\n<option value="12">12</option>\n<option value="13">13</option>\n<option value="14">14</option>\n<option value="15">15</option>\n<option value="16">16</option>\n<option value="17">17</option>\n<option value="18">18</option>\n<option value="19">19</option>\n<option value="20">20</option>\n<option value="21">21</option>\n<option value="22">22</option>\n<option value="23">23</option>\n<option value="24">24</option>\n<option value="25">25</option>\n<option value="26">26</option>\n<option value="27">27</option>\n<option value="28">28</option>\n<option value="29">29</option>\n<option value="30">30</option>\n<option value="31">31</option>\n<option value="32">32</option>\n<option value="33">33</option>\n<option value="34">34</option>\n<option value="35">35</option>\n<option value="36">36</option>\n<option value="37">37</option>\n<option value="38">38</option>\n<option value="39">39</option>\n<option value="40">40</option>\n<option value="41">41</option>\n<option value="42">42</option>\n<option value="43">43</option>\n<option value="44">44</option>\n<option value="45">45</option>\n<option value="46">46</option>\n<option value="47">47</option>\n<option value="48">48</option>\n<option value="49">49</option>\n<option value="50">50</option>\n<option value="51">51</option>\n<option value="52">52</option>\n<option value="53">53</option>\n<option value="54">54</option>\n<option value="55">55</option>\n<option value="56">56</option>\n<option value="57">57</option>\n<option value="58">58</option>\n<option value="59">59</option>\n)
     expected << "</select>\n"
 
-    assert_dom_equal expected, select_minute(nil, :include_blank => true)
+    assert_dom_equal expected, select_minute(nil, include_blank: true)
   end
 
   def test_select_minute_nil_with_blank_and_step
-    expected = %(<select id="date_minute" name="date[minute]">\n)
+    expected = %(<select id="date_minute" name="date[minute]">\n).dup
     expected << %(<option value=""></option>\n<option value="00">00</option>\n<option value="15">15</option>\n<option value="30">30</option>\n<option value="45">45</option>\n)
     expected << "</select>\n"
 
-    assert_dom_equal expected, select_minute(nil, { :include_blank => true , :minute_step => 15 })
+    assert_dom_equal expected, select_minute(nil, include_blank: true, minute_step: 15)
   end
 
   def test_select_minute_with_hidden
-    assert_dom_equal "<input type=\"hidden\" id=\"date_minute\" name=\"date[minute]\" value=\"8\" />\n", select_minute(8, :use_hidden => true)
+    assert_dom_equal "<input type=\"hidden\" id=\"date_minute\" name=\"date[minute]\" value=\"8\" />\n", select_minute(8, use_hidden: true)
   end
 
   def test_select_minute_with_hidden_and_field_name
-    assert_dom_equal "<input type=\"hidden\" id=\"date_minuto\" name=\"date[minuto]\" value=\"8\" />\n", select_minute(8, :use_hidden => true, :field_name => 'minuto')
+    assert_dom_equal "<input type=\"hidden\" id=\"date_minuto\" name=\"date[minuto]\" value=\"8\" />\n", select_minute(8, use_hidden: true, field_name: "minuto")
   end
 
   def test_select_minute_with_html_options
-    expected = %(<select id="date_minute" name="date[minute]" class="selector" accesskey="M">\n)
+    expected = %(<select id="date_minute" name="date[minute]" class="selector" accesskey="M">\n).dup
     expected << %(<option value="00">00</option>\n<option value="01">01</option>\n<option value="02">02</option>\n<option value="03">03</option>\n<option value="04" selected="selected">04</option>\n<option value="05">05</option>\n<option value="06">06</option>\n<option value="07">07</option>\n<option value="08">08</option>\n<option value="09">09</option>\n<option value="10">10</option>\n<option value="11">11</option>\n<option value="12">12</option>\n<option value="13">13</option>\n<option value="14">14</option>\n<option value="15">15</option>\n<option value="16">16</option>\n<option value="17">17</option>\n<option value="18">18</option>\n<option value="19">19</option>\n<option value="20">20</option>\n<option value="21">21</option>\n<option value="22">22</option>\n<option value="23">23</option>\n<option value="24">24</option>\n<option value="25">25</option>\n<option value="26">26</option>\n<option value="27">27</option>\n<option value="28">28</option>\n<option value="29">29</option>\n<option value="30">30</option>\n<option value="31">31</option>\n<option value="32">32</option>\n<option value="33">33</option>\n<option value="34">34</option>\n<option value="35">35</option>\n<option value="36">36</option>\n<option value="37">37</option>\n<option value="38">38</option>\n<option value="39">39</option>\n<option value="40">40</option>\n<option value="41">41</option>\n<option value="42">42</option>\n<option value="43">43</option>\n<option value="44">44</option>\n<option value="45">45</option>\n<option value="46">46</option>\n<option value="47">47</option>\n<option value="48">48</option>\n<option value="49">49</option>\n<option value="50">50</option>\n<option value="51">51</option>\n<option value="52">52</option>\n<option value="53">53</option>\n<option value="54">54</option>\n<option value="55">55</option>\n<option value="56">56</option>\n<option value="57">57</option>\n<option value="58">58</option>\n<option value="59">59</option>\n)
     expected << "</select>\n"
 
-    assert_dom_equal expected, select_minute(Time.mktime(2003, 8, 16, 8, 4, 18), {}, :class => 'selector', :accesskey => 'M')
+    assert_dom_equal expected, select_minute(Time.mktime(2003, 8, 16, 8, 4, 18), {}, { class: "selector", accesskey: "M" })
   end
 
   def test_select_minute_with_default_prompt
-    expected = %(<select id="date_minute" name="date[minute]">\n)
+    expected = %(<select id="date_minute" name="date[minute]">\n).dup
     expected << %(<option value="">Minute</option>\n<option value="00">00</option>\n<option value="01">01</option>\n<option value="02">02</option>\n<option value="03">03</option>\n<option value="04" selected="selected">04</option>\n<option value="05">05</option>\n<option value="06">06</option>\n<option value="07">07</option>\n<option value="08">08</option>\n<option value="09">09</option>\n<option value="10">10</option>\n<option value="11">11</option>\n<option value="12">12</option>\n<option value="13">13</option>\n<option value="14">14</option>\n<option value="15">15</option>\n<option value="16">16</option>\n<option value="17">17</option>\n<option value="18">18</option>\n<option value="19">19</option>\n<option value="20">20</option>\n<option value="21">21</option>\n<option value="22">22</option>\n<option value="23">23</option>\n<option value="24">24</option>\n<option value="25">25</option>\n<option value="26">26</option>\n<option value="27">27</option>\n<option value="28">28</option>\n<option value="29">29</option>\n<option value="30">30</option>\n<option value="31">31</option>\n<option value="32">32</option>\n<option value="33">33</option>\n<option value="34">34</option>\n<option value="35">35</option>\n<option value="36">36</option>\n<option value="37">37</option>\n<option value="38">38</option>\n<option value="39">39</option>\n<option value="40">40</option>\n<option value="41">41</option>\n<option value="42">42</option>\n<option value="43">43</option>\n<option value="44">44</option>\n<option value="45">45</option>\n<option value="46">46</option>\n<option value="47">47</option>\n<option value="48">48</option>\n<option value="49">49</option>\n<option value="50">50</option>\n<option value="51">51</option>\n<option value="52">52</option>\n<option value="53">53</option>\n<option value="54">54</option>\n<option value="55">55</option>\n<option value="56">56</option>\n<option value="57">57</option>\n<option value="58">58</option>\n<option value="59">59</option>\n)
     expected << "</select>\n"
 
-    assert_dom_equal expected, select_minute(Time.mktime(2003, 8, 16, 8, 4, 18), :prompt => true)
+    assert_dom_equal expected, select_minute(Time.mktime(2003, 8, 16, 8, 4, 18), prompt: true)
   end
 
   def test_select_minute_with_custom_prompt
-    expected = %(<select id="date_minute" name="date[minute]">\n)
+    expected = %(<select id="date_minute" name="date[minute]">\n).dup
     expected << %(<option value="">Choose minute</option>\n<option value="00">00</option>\n<option value="01">01</option>\n<option value="02">02</option>\n<option value="03">03</option>\n<option value="04" selected="selected">04</option>\n<option value="05">05</option>\n<option value="06">06</option>\n<option value="07">07</option>\n<option value="08">08</option>\n<option value="09">09</option>\n<option value="10">10</option>\n<option value="11">11</option>\n<option value="12">12</option>\n<option value="13">13</option>\n<option value="14">14</option>\n<option value="15">15</option>\n<option value="16">16</option>\n<option value="17">17</option>\n<option value="18">18</option>\n<option value="19">19</option>\n<option value="20">20</option>\n<option value="21">21</option>\n<option value="22">22</option>\n<option value="23">23</option>\n<option value="24">24</option>\n<option value="25">25</option>\n<option value="26">26</option>\n<option value="27">27</option>\n<option value="28">28</option>\n<option value="29">29</option>\n<option value="30">30</option>\n<option value="31">31</option>\n<option value="32">32</option>\n<option value="33">33</option>\n<option value="34">34</option>\n<option value="35">35</option>\n<option value="36">36</option>\n<option value="37">37</option>\n<option value="38">38</option>\n<option value="39">39</option>\n<option value="40">40</option>\n<option value="41">41</option>\n<option value="42">42</option>\n<option value="43">43</option>\n<option value="44">44</option>\n<option value="45">45</option>\n<option value="46">46</option>\n<option value="47">47</option>\n<option value="48">48</option>\n<option value="49">49</option>\n<option value="50">50</option>\n<option value="51">51</option>\n<option value="52">52</option>\n<option value="53">53</option>\n<option value="54">54</option>\n<option value="55">55</option>\n<option value="56">56</option>\n<option value="57">57</option>\n<option value="58">58</option>\n<option value="59">59</option>\n)
     expected << "</select>\n"
 
-    assert_dom_equal expected, select_minute(Time.mktime(2003, 8, 16, 8, 4, 18), :prompt => 'Choose minute')
+    assert_dom_equal expected, select_minute(Time.mktime(2003, 8, 16, 8, 4, 18), prompt: "Choose minute")
   end
 
   def test_select_minute_with_generic_with_css_classes
-    expected = %(<select id="date_minute" name="date[minute]" class="minute">\n)
+    expected = %(<select id="date_minute" name="date[minute]" class="minute">\n).dup
     expected << %(<option value="00">00</option>\n<option value="01">01</option>\n<option value="02">02</option>\n<option value="03">03</option>\n<option value="04" selected="selected">04</option>\n<option value="05">05</option>\n<option value="06">06</option>\n<option value="07">07</option>\n<option value="08">08</option>\n<option value="09">09</option>\n<option value="10">10</option>\n<option value="11">11</option>\n<option value="12">12</option>\n<option value="13">13</option>\n<option value="14">14</option>\n<option value="15">15</option>\n<option value="16">16</option>\n<option value="17">17</option>\n<option value="18">18</option>\n<option value="19">19</option>\n<option value="20">20</option>\n<option value="21">21</option>\n<option value="22">22</option>\n<option value="23">23</option>\n<option value="24">24</option>\n<option value="25">25</option>\n<option value="26">26</option>\n<option value="27">27</option>\n<option value="28">28</option>\n<option value="29">29</option>\n<option value="30">30</option>\n<option value="31">31</option>\n<option value="32">32</option>\n<option value="33">33</option>\n<option value="34">34</option>\n<option value="35">35</option>\n<option value="36">36</option>\n<option value="37">37</option>\n<option value="38">38</option>\n<option value="39">39</option>\n<option value="40">40</option>\n<option value="41">41</option>\n<option value="42">42</option>\n<option value="43">43</option>\n<option value="44">44</option>\n<option value="45">45</option>\n<option value="46">46</option>\n<option value="47">47</option>\n<option value="48">48</option>\n<option value="49">49</option>\n<option value="50">50</option>\n<option value="51">51</option>\n<option value="52">52</option>\n<option value="53">53</option>\n<option value="54">54</option>\n<option value="55">55</option>\n<option value="56">56</option>\n<option value="57">57</option>\n<option value="58">58</option>\n<option value="59">59</option>\n)
     expected << "</select>\n"
 
@@ -720,15 +747,15 @@ class DateHelperTest < ActionView::TestCase
   end
 
   def test_select_minute_with_custom_with_css_classes
-    expected = %(<select id="date_minute" name="date[minute]" class="my-minute">\n)
+    expected = %(<select id="date_minute" name="date[minute]" class="my-minute">\n).dup
     expected << %(<option value="00">00</option>\n<option value="01">01</option>\n<option value="02">02</option>\n<option value="03">03</option>\n<option value="04" selected="selected">04</option>\n<option value="05">05</option>\n<option value="06">06</option>\n<option value="07">07</option>\n<option value="08">08</option>\n<option value="09">09</option>\n<option value="10">10</option>\n<option value="11">11</option>\n<option value="12">12</option>\n<option value="13">13</option>\n<option value="14">14</option>\n<option value="15">15</option>\n<option value="16">16</option>\n<option value="17">17</option>\n<option value="18">18</option>\n<option value="19">19</option>\n<option value="20">20</option>\n<option value="21">21</option>\n<option value="22">22</option>\n<option value="23">23</option>\n<option value="24">24</option>\n<option value="25">25</option>\n<option value="26">26</option>\n<option value="27">27</option>\n<option value="28">28</option>\n<option value="29">29</option>\n<option value="30">30</option>\n<option value="31">31</option>\n<option value="32">32</option>\n<option value="33">33</option>\n<option value="34">34</option>\n<option value="35">35</option>\n<option value="36">36</option>\n<option value="37">37</option>\n<option value="38">38</option>\n<option value="39">39</option>\n<option value="40">40</option>\n<option value="41">41</option>\n<option value="42">42</option>\n<option value="43">43</option>\n<option value="44">44</option>\n<option value="45">45</option>\n<option value="46">46</option>\n<option value="47">47</option>\n<option value="48">48</option>\n<option value="49">49</option>\n<option value="50">50</option>\n<option value="51">51</option>\n<option value="52">52</option>\n<option value="53">53</option>\n<option value="54">54</option>\n<option value="55">55</option>\n<option value="56">56</option>\n<option value="57">57</option>\n<option value="58">58</option>\n<option value="59">59</option>\n)
     expected << "</select>\n"
 
-    assert_dom_equal expected, select_minute(Time.mktime(2003, 8, 16, 8, 4, 18), with_css_classes: { minute: 'my-minute' })
+    assert_dom_equal expected, select_minute(Time.mktime(2003, 8, 16, 8, 4, 18), with_css_classes: { minute: "my-minute" })
   end
 
   def test_select_second
-    expected = %(<select id="date_second" name="date[second]">\n)
+    expected = %(<select id="date_second" name="date[second]">\n).dup
     expected << %(<option value="00">00</option>\n<option value="01">01</option>\n<option value="02">02</option>\n<option value="03">03</option>\n<option value="04">04</option>\n<option value="05">05</option>\n<option value="06">06</option>\n<option value="07">07</option>\n<option value="08">08</option>\n<option value="09">09</option>\n<option value="10">10</option>\n<option value="11">11</option>\n<option value="12">12</option>\n<option value="13">13</option>\n<option value="14">14</option>\n<option value="15">15</option>\n<option value="16">16</option>\n<option value="17">17</option>\n<option value="18" selected="selected">18</option>\n<option value="19">19</option>\n<option value="20">20</option>\n<option value="21">21</option>\n<option value="22">22</option>\n<option value="23">23</option>\n<option value="24">24</option>\n<option value="25">25</option>\n<option value="26">26</option>\n<option value="27">27</option>\n<option value="28">28</option>\n<option value="29">29</option>\n<option value="30">30</option>\n<option value="31">31</option>\n<option value="32">32</option>\n<option value="33">33</option>\n<option value="34">34</option>\n<option value="35">35</option>\n<option value="36">36</option>\n<option value="37">37</option>\n<option value="38">38</option>\n<option value="39">39</option>\n<option value="40">40</option>\n<option value="41">41</option>\n<option value="42">42</option>\n<option value="43">43</option>\n<option value="44">44</option>\n<option value="45">45</option>\n<option value="46">46</option>\n<option value="47">47</option>\n<option value="48">48</option>\n<option value="49">49</option>\n<option value="50">50</option>\n<option value="51">51</option>\n<option value="52">52</option>\n<option value="53">53</option>\n<option value="54">54</option>\n<option value="55">55</option>\n<option value="56">56</option>\n<option value="57">57</option>\n<option value="58">58</option>\n<option value="59">59</option>\n)
     expected << "</select>\n"
 
@@ -736,63 +763,63 @@ class DateHelperTest < ActionView::TestCase
   end
 
   def test_select_second_with_disabled
-    expected = %(<select id="date_second" name="date[second]" disabled="disabled">\n)
+    expected = %(<select id="date_second" name="date[second]" disabled="disabled">\n).dup
     expected << %(<option value="00">00</option>\n<option value="01">01</option>\n<option value="02">02</option>\n<option value="03">03</option>\n<option value="04">04</option>\n<option value="05">05</option>\n<option value="06">06</option>\n<option value="07">07</option>\n<option value="08">08</option>\n<option value="09">09</option>\n<option value="10">10</option>\n<option value="11">11</option>\n<option value="12">12</option>\n<option value="13">13</option>\n<option value="14">14</option>\n<option value="15">15</option>\n<option value="16">16</option>\n<option value="17">17</option>\n<option value="18" selected="selected">18</option>\n<option value="19">19</option>\n<option value="20">20</option>\n<option value="21">21</option>\n<option value="22">22</option>\n<option value="23">23</option>\n<option value="24">24</option>\n<option value="25">25</option>\n<option value="26">26</option>\n<option value="27">27</option>\n<option value="28">28</option>\n<option value="29">29</option>\n<option value="30">30</option>\n<option value="31">31</option>\n<option value="32">32</option>\n<option value="33">33</option>\n<option value="34">34</option>\n<option value="35">35</option>\n<option value="36">36</option>\n<option value="37">37</option>\n<option value="38">38</option>\n<option value="39">39</option>\n<option value="40">40</option>\n<option value="41">41</option>\n<option value="42">42</option>\n<option value="43">43</option>\n<option value="44">44</option>\n<option value="45">45</option>\n<option value="46">46</option>\n<option value="47">47</option>\n<option value="48">48</option>\n<option value="49">49</option>\n<option value="50">50</option>\n<option value="51">51</option>\n<option value="52">52</option>\n<option value="53">53</option>\n<option value="54">54</option>\n<option value="55">55</option>\n<option value="56">56</option>\n<option value="57">57</option>\n<option value="58">58</option>\n<option value="59">59</option>\n)
     expected << "</select>\n"
 
-    assert_dom_equal expected, select_second(Time.mktime(2003, 8, 16, 8, 4, 18), :disabled => true)
+    assert_dom_equal expected, select_second(Time.mktime(2003, 8, 16, 8, 4, 18), disabled: true)
   end
 
   def test_select_second_with_field_name_override
-    expected = %(<select id="date_segundo" name="date[segundo]">\n)
+    expected = %(<select id="date_segundo" name="date[segundo]">\n).dup
     expected << %(<option value="00">00</option>\n<option value="01">01</option>\n<option value="02">02</option>\n<option value="03">03</option>\n<option value="04">04</option>\n<option value="05">05</option>\n<option value="06">06</option>\n<option value="07">07</option>\n<option value="08">08</option>\n<option value="09">09</option>\n<option value="10">10</option>\n<option value="11">11</option>\n<option value="12">12</option>\n<option value="13">13</option>\n<option value="14">14</option>\n<option value="15">15</option>\n<option value="16">16</option>\n<option value="17">17</option>\n<option value="18" selected="selected">18</option>\n<option value="19">19</option>\n<option value="20">20</option>\n<option value="21">21</option>\n<option value="22">22</option>\n<option value="23">23</option>\n<option value="24">24</option>\n<option value="25">25</option>\n<option value="26">26</option>\n<option value="27">27</option>\n<option value="28">28</option>\n<option value="29">29</option>\n<option value="30">30</option>\n<option value="31">31</option>\n<option value="32">32</option>\n<option value="33">33</option>\n<option value="34">34</option>\n<option value="35">35</option>\n<option value="36">36</option>\n<option value="37">37</option>\n<option value="38">38</option>\n<option value="39">39</option>\n<option value="40">40</option>\n<option value="41">41</option>\n<option value="42">42</option>\n<option value="43">43</option>\n<option value="44">44</option>\n<option value="45">45</option>\n<option value="46">46</option>\n<option value="47">47</option>\n<option value="48">48</option>\n<option value="49">49</option>\n<option value="50">50</option>\n<option value="51">51</option>\n<option value="52">52</option>\n<option value="53">53</option>\n<option value="54">54</option>\n<option value="55">55</option>\n<option value="56">56</option>\n<option value="57">57</option>\n<option value="58">58</option>\n<option value="59">59</option>\n)
     expected << "</select>\n"
 
-    assert_dom_equal expected, select_second(Time.mktime(2003, 8, 16, 8, 4, 18), :field_name => 'segundo')
+    assert_dom_equal expected, select_second(Time.mktime(2003, 8, 16, 8, 4, 18), field_name: "segundo")
   end
 
   def test_select_second_with_blank
-    expected = %(<select id="date_second" name="date[second]">\n)
+    expected = %(<select id="date_second" name="date[second]">\n).dup
     expected << %(<option value=""></option>\n<option value="00">00</option>\n<option value="01">01</option>\n<option value="02">02</option>\n<option value="03">03</option>\n<option value="04">04</option>\n<option value="05">05</option>\n<option value="06">06</option>\n<option value="07">07</option>\n<option value="08">08</option>\n<option value="09">09</option>\n<option value="10">10</option>\n<option value="11">11</option>\n<option value="12">12</option>\n<option value="13">13</option>\n<option value="14">14</option>\n<option value="15">15</option>\n<option value="16">16</option>\n<option value="17">17</option>\n<option value="18" selected="selected">18</option>\n<option value="19">19</option>\n<option value="20">20</option>\n<option value="21">21</option>\n<option value="22">22</option>\n<option value="23">23</option>\n<option value="24">24</option>\n<option value="25">25</option>\n<option value="26">26</option>\n<option value="27">27</option>\n<option value="28">28</option>\n<option value="29">29</option>\n<option value="30">30</option>\n<option value="31">31</option>\n<option value="32">32</option>\n<option value="33">33</option>\n<option value="34">34</option>\n<option value="35">35</option>\n<option value="36">36</option>\n<option value="37">37</option>\n<option value="38">38</option>\n<option value="39">39</option>\n<option value="40">40</option>\n<option value="41">41</option>\n<option value="42">42</option>\n<option value="43">43</option>\n<option value="44">44</option>\n<option value="45">45</option>\n<option value="46">46</option>\n<option value="47">47</option>\n<option value="48">48</option>\n<option value="49">49</option>\n<option value="50">50</option>\n<option value="51">51</option>\n<option value="52">52</option>\n<option value="53">53</option>\n<option value="54">54</option>\n<option value="55">55</option>\n<option value="56">56</option>\n<option value="57">57</option>\n<option value="58">58</option>\n<option value="59">59</option>\n)
     expected << "</select>\n"
 
-    assert_dom_equal expected, select_second(Time.mktime(2003, 8, 16, 8, 4, 18), :include_blank => true)
+    assert_dom_equal expected, select_second(Time.mktime(2003, 8, 16, 8, 4, 18), include_blank: true)
   end
 
   def test_select_second_nil_with_blank
-    expected = %(<select id="date_second" name="date[second]">\n)
+    expected = %(<select id="date_second" name="date[second]">\n).dup
     expected << %(<option value=""></option>\n<option value="00">00</option>\n<option value="01">01</option>\n<option value="02">02</option>\n<option value="03">03</option>\n<option value="04">04</option>\n<option value="05">05</option>\n<option value="06">06</option>\n<option value="07">07</option>\n<option value="08">08</option>\n<option value="09">09</option>\n<option value="10">10</option>\n<option value="11">11</option>\n<option value="12">12</option>\n<option value="13">13</option>\n<option value="14">14</option>\n<option value="15">15</option>\n<option value="16">16</option>\n<option value="17">17</option>\n<option value="18">18</option>\n<option value="19">19</option>\n<option value="20">20</option>\n<option value="21">21</option>\n<option value="22">22</option>\n<option value="23">23</option>\n<option value="24">24</option>\n<option value="25">25</option>\n<option value="26">26</option>\n<option value="27">27</option>\n<option value="28">28</option>\n<option value="29">29</option>\n<option value="30">30</option>\n<option value="31">31</option>\n<option value="32">32</option>\n<option value="33">33</option>\n<option value="34">34</option>\n<option value="35">35</option>\n<option value="36">36</option>\n<option value="37">37</option>\n<option value="38">38</option>\n<option value="39">39</option>\n<option value="40">40</option>\n<option value="41">41</option>\n<option value="42">42</option>\n<option value="43">43</option>\n<option value="44">44</option>\n<option value="45">45</option>\n<option value="46">46</option>\n<option value="47">47</option>\n<option value="48">48</option>\n<option value="49">49</option>\n<option value="50">50</option>\n<option value="51">51</option>\n<option value="52">52</option>\n<option value="53">53</option>\n<option value="54">54</option>\n<option value="55">55</option>\n<option value="56">56</option>\n<option value="57">57</option>\n<option value="58">58</option>\n<option value="59">59</option>\n)
     expected << "</select>\n"
 
-    assert_dom_equal expected, select_second(nil, :include_blank => true)
+    assert_dom_equal expected, select_second(nil, include_blank: true)
   end
 
   def test_select_second_with_html_options
-    expected = %(<select id="date_second" name="date[second]" class="selector" accesskey="M">\n)
+    expected = %(<select id="date_second" name="date[second]" class="selector" accesskey="M">\n).dup
     expected << %(<option value="00">00</option>\n<option value="01">01</option>\n<option value="02">02</option>\n<option value="03">03</option>\n<option value="04">04</option>\n<option value="05">05</option>\n<option value="06">06</option>\n<option value="07">07</option>\n<option value="08">08</option>\n<option value="09">09</option>\n<option value="10">10</option>\n<option value="11">11</option>\n<option value="12">12</option>\n<option value="13">13</option>\n<option value="14">14</option>\n<option value="15">15</option>\n<option value="16">16</option>\n<option value="17">17</option>\n<option value="18" selected="selected">18</option>\n<option value="19">19</option>\n<option value="20">20</option>\n<option value="21">21</option>\n<option value="22">22</option>\n<option value="23">23</option>\n<option value="24">24</option>\n<option value="25">25</option>\n<option value="26">26</option>\n<option value="27">27</option>\n<option value="28">28</option>\n<option value="29">29</option>\n<option value="30">30</option>\n<option value="31">31</option>\n<option value="32">32</option>\n<option value="33">33</option>\n<option value="34">34</option>\n<option value="35">35</option>\n<option value="36">36</option>\n<option value="37">37</option>\n<option value="38">38</option>\n<option value="39">39</option>\n<option value="40">40</option>\n<option value="41">41</option>\n<option value="42">42</option>\n<option value="43">43</option>\n<option value="44">44</option>\n<option value="45">45</option>\n<option value="46">46</option>\n<option value="47">47</option>\n<option value="48">48</option>\n<option value="49">49</option>\n<option value="50">50</option>\n<option value="51">51</option>\n<option value="52">52</option>\n<option value="53">53</option>\n<option value="54">54</option>\n<option value="55">55</option>\n<option value="56">56</option>\n<option value="57">57</option>\n<option value="58">58</option>\n<option value="59">59</option>\n)
     expected << "</select>\n"
 
-    assert_dom_equal expected, select_second(Time.mktime(2003, 8, 16, 8, 4, 18), {}, :class => 'selector', :accesskey => 'M')
+    assert_dom_equal expected, select_second(Time.mktime(2003, 8, 16, 8, 4, 18), {}, { class: "selector", accesskey: "M" })
   end
 
   def test_select_second_with_default_prompt
-    expected = %(<select id="date_second" name="date[second]">\n)
+    expected = %(<select id="date_second" name="date[second]">\n).dup
     expected << %(<option value="">Seconds</option>\n<option value="00">00</option>\n<option value="01">01</option>\n<option value="02">02</option>\n<option value="03">03</option>\n<option value="04">04</option>\n<option value="05">05</option>\n<option value="06">06</option>\n<option value="07">07</option>\n<option value="08">08</option>\n<option value="09">09</option>\n<option value="10">10</option>\n<option value="11">11</option>\n<option value="12">12</option>\n<option value="13">13</option>\n<option value="14">14</option>\n<option value="15">15</option>\n<option value="16">16</option>\n<option value="17">17</option>\n<option value="18" selected="selected">18</option>\n<option value="19">19</option>\n<option value="20">20</option>\n<option value="21">21</option>\n<option value="22">22</option>\n<option value="23">23</option>\n<option value="24">24</option>\n<option value="25">25</option>\n<option value="26">26</option>\n<option value="27">27</option>\n<option value="28">28</option>\n<option value="29">29</option>\n<option value="30">30</option>\n<option value="31">31</option>\n<option value="32">32</option>\n<option value="33">33</option>\n<option value="34">34</option>\n<option value="35">35</option>\n<option value="36">36</option>\n<option value="37">37</option>\n<option value="38">38</option>\n<option value="39">39</option>\n<option value="40">40</option>\n<option value="41">41</option>\n<option value="42">42</option>\n<option value="43">43</option>\n<option value="44">44</option>\n<option value="45">45</option>\n<option value="46">46</option>\n<option value="47">47</option>\n<option value="48">48</option>\n<option value="49">49</option>\n<option value="50">50</option>\n<option value="51">51</option>\n<option value="52">52</option>\n<option value="53">53</option>\n<option value="54">54</option>\n<option value="55">55</option>\n<option value="56">56</option>\n<option value="57">57</option>\n<option value="58">58</option>\n<option value="59">59</option>\n)
     expected << "</select>\n"
 
-    assert_dom_equal expected, select_second(Time.mktime(2003, 8, 16, 8, 4, 18), :prompt => true)
+    assert_dom_equal expected, select_second(Time.mktime(2003, 8, 16, 8, 4, 18), prompt: true)
   end
 
   def test_select_second_with_custom_prompt
-    expected = %(<select id="date_second" name="date[second]">\n)
+    expected = %(<select id="date_second" name="date[second]">\n).dup
     expected << %(<option value="">Choose seconds</option>\n<option value="00">00</option>\n<option value="01">01</option>\n<option value="02">02</option>\n<option value="03">03</option>\n<option value="04">04</option>\n<option value="05">05</option>\n<option value="06">06</option>\n<option value="07">07</option>\n<option value="08">08</option>\n<option value="09">09</option>\n<option value="10">10</option>\n<option value="11">11</option>\n<option value="12">12</option>\n<option value="13">13</option>\n<option value="14">14</option>\n<option value="15">15</option>\n<option value="16">16</option>\n<option value="17">17</option>\n<option value="18" selected="selected">18</option>\n<option value="19">19</option>\n<option value="20">20</option>\n<option value="21">21</option>\n<option value="22">22</option>\n<option value="23">23</option>\n<option value="24">24</option>\n<option value="25">25</option>\n<option value="26">26</option>\n<option value="27">27</option>\n<option value="28">28</option>\n<option value="29">29</option>\n<option value="30">30</option>\n<option value="31">31</option>\n<option value="32">32</option>\n<option value="33">33</option>\n<option value="34">34</option>\n<option value="35">35</option>\n<option value="36">36</option>\n<option value="37">37</option>\n<option value="38">38</option>\n<option value="39">39</option>\n<option value="40">40</option>\n<option value="41">41</option>\n<option value="42">42</option>\n<option value="43">43</option>\n<option value="44">44</option>\n<option value="45">45</option>\n<option value="46">46</option>\n<option value="47">47</option>\n<option value="48">48</option>\n<option value="49">49</option>\n<option value="50">50</option>\n<option value="51">51</option>\n<option value="52">52</option>\n<option value="53">53</option>\n<option value="54">54</option>\n<option value="55">55</option>\n<option value="56">56</option>\n<option value="57">57</option>\n<option value="58">58</option>\n<option value="59">59</option>\n)
     expected << "</select>\n"
 
-    assert_dom_equal expected, select_second(Time.mktime(2003, 8, 16, 8, 4, 18), :prompt => 'Choose seconds')
+    assert_dom_equal expected, select_second(Time.mktime(2003, 8, 16, 8, 4, 18), prompt: "Choose seconds")
   end
 
   def test_select_second_with_generic_with_css_classes
-    expected = %(<select id="date_second" name="date[second]" class="second">\n)
+    expected = %(<select id="date_second" name="date[second]" class="second">\n).dup
     expected << %(<option value="00">00</option>\n<option value="01">01</option>\n<option value="02">02</option>\n<option value="03">03</option>\n<option value="04">04</option>\n<option value="05">05</option>\n<option value="06">06</option>\n<option value="07">07</option>\n<option value="08">08</option>\n<option value="09">09</option>\n<option value="10">10</option>\n<option value="11">11</option>\n<option value="12">12</option>\n<option value="13">13</option>\n<option value="14">14</option>\n<option value="15">15</option>\n<option value="16">16</option>\n<option value="17">17</option>\n<option value="18" selected="selected">18</option>\n<option value="19">19</option>\n<option value="20">20</option>\n<option value="21">21</option>\n<option value="22">22</option>\n<option value="23">23</option>\n<option value="24">24</option>\n<option value="25">25</option>\n<option value="26">26</option>\n<option value="27">27</option>\n<option value="28">28</option>\n<option value="29">29</option>\n<option value="30">30</option>\n<option value="31">31</option>\n<option value="32">32</option>\n<option value="33">33</option>\n<option value="34">34</option>\n<option value="35">35</option>\n<option value="36">36</option>\n<option value="37">37</option>\n<option value="38">38</option>\n<option value="39">39</option>\n<option value="40">40</option>\n<option value="41">41</option>\n<option value="42">42</option>\n<option value="43">43</option>\n<option value="44">44</option>\n<option value="45">45</option>\n<option value="46">46</option>\n<option value="47">47</option>\n<option value="48">48</option>\n<option value="49">49</option>\n<option value="50">50</option>\n<option value="51">51</option>\n<option value="52">52</option>\n<option value="53">53</option>\n<option value="54">54</option>\n<option value="55">55</option>\n<option value="56">56</option>\n<option value="57">57</option>\n<option value="58">58</option>\n<option value="59">59</option>\n)
     expected << "</select>\n"
 
@@ -800,15 +827,15 @@ class DateHelperTest < ActionView::TestCase
   end
 
   def test_select_second_with_custom_with_css_classes
-    expected = %(<select id="date_second" name="date[second]" class="my-second">\n)
+    expected = %(<select id="date_second" name="date[second]" class="my-second">\n).dup
     expected << %(<option value="00">00</option>\n<option value="01">01</option>\n<option value="02">02</option>\n<option value="03">03</option>\n<option value="04">04</option>\n<option value="05">05</option>\n<option value="06">06</option>\n<option value="07">07</option>\n<option value="08">08</option>\n<option value="09">09</option>\n<option value="10">10</option>\n<option value="11">11</option>\n<option value="12">12</option>\n<option value="13">13</option>\n<option value="14">14</option>\n<option value="15">15</option>\n<option value="16">16</option>\n<option value="17">17</option>\n<option value="18" selected="selected">18</option>\n<option value="19">19</option>\n<option value="20">20</option>\n<option value="21">21</option>\n<option value="22">22</option>\n<option value="23">23</option>\n<option value="24">24</option>\n<option value="25">25</option>\n<option value="26">26</option>\n<option value="27">27</option>\n<option value="28">28</option>\n<option value="29">29</option>\n<option value="30">30</option>\n<option value="31">31</option>\n<option value="32">32</option>\n<option value="33">33</option>\n<option value="34">34</option>\n<option value="35">35</option>\n<option value="36">36</option>\n<option value="37">37</option>\n<option value="38">38</option>\n<option value="39">39</option>\n<option value="40">40</option>\n<option value="41">41</option>\n<option value="42">42</option>\n<option value="43">43</option>\n<option value="44">44</option>\n<option value="45">45</option>\n<option value="46">46</option>\n<option value="47">47</option>\n<option value="48">48</option>\n<option value="49">49</option>\n<option value="50">50</option>\n<option value="51">51</option>\n<option value="52">52</option>\n<option value="53">53</option>\n<option value="54">54</option>\n<option value="55">55</option>\n<option value="56">56</option>\n<option value="57">57</option>\n<option value="58">58</option>\n<option value="59">59</option>\n)
     expected << "</select>\n"
 
-    assert_dom_equal expected, select_second(Time.mktime(2003, 8, 16, 8, 4, 18), with_css_classes: { second: 'my-second' })
+    assert_dom_equal expected, select_second(Time.mktime(2003, 8, 16, 8, 4, 18), with_css_classes: { second: "my-second" })
   end
 
   def test_select_date
-    expected =  %(<select id="date_first_year" name="date[first][year]">\n)
+    expected =  %(<select id="date_first_year" name="date[first][year]">\n).dup
     expected << %(<option value="2003" selected="selected">2003</option>\n<option value="2004">2004</option>\n<option value="2005">2005</option>\n)
     expected << "</select>\n"
 
@@ -820,20 +847,20 @@ class DateHelperTest < ActionView::TestCase
     expected << %(<option value="1">1</option>\n<option value="2">2</option>\n<option value="3">3</option>\n<option value="4">4</option>\n<option value="5">5</option>\n<option value="6">6</option>\n<option value="7">7</option>\n<option value="8">8</option>\n<option value="9">9</option>\n<option value="10">10</option>\n<option value="11">11</option>\n<option value="12">12</option>\n<option value="13">13</option>\n<option value="14">14</option>\n<option value="15">15</option>\n<option value="16" selected="selected">16</option>\n<option value="17">17</option>\n<option value="18">18</option>\n<option value="19">19</option>\n<option value="20">20</option>\n<option value="21">21</option>\n<option value="22">22</option>\n<option value="23">23</option>\n<option value="24">24</option>\n<option value="25">25</option>\n<option value="26">26</option>\n<option value="27">27</option>\n<option value="28">28</option>\n<option value="29">29</option>\n<option value="30">30</option>\n<option value="31">31</option>\n)
     expected << "</select>\n"
 
-    assert_dom_equal expected, select_date(Time.mktime(2003, 8, 16), :start_year => 2003, :end_year => 2005, :prefix => "date[first]")
+    assert_dom_equal expected, select_date(Time.mktime(2003, 8, 16), start_year: 2003, end_year: 2005, prefix: "date[first]")
   end
 
   def test_select_date_with_too_big_range_between_start_year_and_end_year
-    assert_raise(ArgumentError) { select_date(Time.mktime(2003, 8, 16), :start_year => 2000, :end_year => 20000, :prefix => "date[first]", :order => [:month, :day, :year]) }
-    assert_raise(ArgumentError) { select_date(Time.mktime(2003, 8, 16), :start_year => Date.today.year - 100.years, :end_year => 2000, :prefix => "date[first]", :order => [:month, :day, :year]) }
+    assert_raise(ArgumentError) { select_date(Time.mktime(2003, 8, 16), start_year: 2000, end_year: 20000, prefix: "date[first]", order: [:month, :day, :year]) }
+    assert_raise(ArgumentError) { select_date(Time.mktime(2003, 8, 16), start_year: 100, end_year: 2000, prefix: "date[first]", order: [:month, :day, :year]) }
   end
 
   def test_select_date_can_have_more_then_1000_years_interval_if_forced_via_parameter
-    assert_nothing_raised { select_date(Time.mktime(2003, 8, 16), :start_year => 2000, :end_year => 3100, :max_years_allowed => 2000) }
+    assert_nothing_raised { select_date(Time.mktime(2003, 8, 16), start_year: 2000, end_year: 3100, max_years_allowed: 2000) }
   end
 
   def test_select_date_with_order
-    expected = %(<select id="date_first_month" name="date[first][month]">\n)
+    expected = %(<select id="date_first_month" name="date[first][month]">\n).dup
     expected << %(<option value="1">January</option>\n<option value="2">February</option>\n<option value="3">March</option>\n<option value="4">April</option>\n<option value="5">May</option>\n<option value="6">June</option>\n<option value="7">July</option>\n<option value="8" selected="selected">August</option>\n<option value="9">September</option>\n<option value="10">October</option>\n<option value="11">November</option>\n<option value="12">December</option>\n)
     expected << "</select>\n"
 
@@ -841,24 +868,24 @@ class DateHelperTest < ActionView::TestCase
     expected << %(<option value="1">1</option>\n<option value="2">2</option>\n<option value="3">3</option>\n<option value="4">4</option>\n<option value="5">5</option>\n<option value="6">6</option>\n<option value="7">7</option>\n<option value="8">8</option>\n<option value="9">9</option>\n<option value="10">10</option>\n<option value="11">11</option>\n<option value="12">12</option>\n<option value="13">13</option>\n<option value="14">14</option>\n<option value="15">15</option>\n<option value="16" selected="selected">16</option>\n<option value="17">17</option>\n<option value="18">18</option>\n<option value="19">19</option>\n<option value="20">20</option>\n<option value="21">21</option>\n<option value="22">22</option>\n<option value="23">23</option>\n<option value="24">24</option>\n<option value="25">25</option>\n<option value="26">26</option>\n<option value="27">27</option>\n<option value="28">28</option>\n<option value="29">29</option>\n<option value="30">30</option>\n<option value="31">31</option>\n)
     expected << "</select>\n"
 
-    expected <<  %(<select id="date_first_year" name="date[first][year]">\n)
+    expected << %(<select id="date_first_year" name="date[first][year]">\n)
     expected << %(<option value="2003" selected="selected">2003</option>\n<option value="2004">2004</option>\n<option value="2005">2005</option>\n)
     expected << "</select>\n"
 
-    assert_dom_equal expected, select_date(Time.mktime(2003, 8, 16), :start_year => 2003, :end_year => 2005, :prefix => "date[first]", :order => [:month, :day, :year])
+    assert_dom_equal expected, select_date(Time.mktime(2003, 8, 16), start_year: 2003, end_year: 2005, prefix: "date[first]", order: [:month, :day, :year])
   end
 
   def test_select_date_with_incomplete_order
     # Since the order is incomplete nothing will be shown
-    expected = %(<input id="date_first_year" name="date[first][year]" type="hidden" value="2003" />\n)
+    expected = %(<input id="date_first_year" name="date[first][year]" type="hidden" value="2003" />\n).dup
     expected << %(<input id="date_first_month" name="date[first][month]" type="hidden" value="8" />\n)
     expected << %(<input id="date_first_day" name="date[first][day]" type="hidden" value="1" />\n)
 
-    assert_dom_equal expected, select_date(Time.mktime(2003, 8, 16), :start_year => 2003, :end_year => 2005, :prefix => "date[first]", :order => [:day])
+    assert_dom_equal expected, select_date(Time.mktime(2003, 8, 16), start_year: 2003, end_year: 2005, prefix: "date[first]", order: [:day])
   end
 
   def test_select_date_with_disabled
-    expected =  %(<select id="date_first_year" name="date[first][year]" disabled="disabled">\n)
+    expected =  %(<select id="date_first_year" name="date[first][year]" disabled="disabled">\n).dup
     expected << %(<option value="2003" selected="selected">2003</option>\n<option value="2004">2004</option>\n<option value="2005">2005</option>\n)
     expected << "</select>\n"
 
@@ -870,12 +897,12 @@ class DateHelperTest < ActionView::TestCase
     expected << %(<option value="1">1</option>\n<option value="2">2</option>\n<option value="3">3</option>\n<option value="4">4</option>\n<option value="5">5</option>\n<option value="6">6</option>\n<option value="7">7</option>\n<option value="8">8</option>\n<option value="9">9</option>\n<option value="10">10</option>\n<option value="11">11</option>\n<option value="12">12</option>\n<option value="13">13</option>\n<option value="14">14</option>\n<option value="15">15</option>\n<option value="16" selected="selected">16</option>\n<option value="17">17</option>\n<option value="18">18</option>\n<option value="19">19</option>\n<option value="20">20</option>\n<option value="21">21</option>\n<option value="22">22</option>\n<option value="23">23</option>\n<option value="24">24</option>\n<option value="25">25</option>\n<option value="26">26</option>\n<option value="27">27</option>\n<option value="28">28</option>\n<option value="29">29</option>\n<option value="30">30</option>\n<option value="31">31</option>\n)
     expected << "</select>\n"
 
-    assert_dom_equal expected, select_date(Time.mktime(2003, 8, 16), :start_year => 2003, :end_year => 2005, :prefix => "date[first]", :disabled => true)
+    assert_dom_equal expected, select_date(Time.mktime(2003, 8, 16), start_year: 2003, end_year: 2005, prefix: "date[first]", disabled: true)
   end
 
   def test_select_date_with_no_start_year
-    expected =  %(<select id="date_first_year" name="date[first][year]">\n)
-    (Date.today.year-5).upto(Date.today.year+1) do |y|
+    expected = %(<select id="date_first_year" name="date[first][year]">\n).dup
+    (Date.today.year - 5).upto(Date.today.year + 1) do |y|
       if y == Date.today.year
         expected << %(<option value="#{y}" selected="selected">#{y}</option>\n)
       else
@@ -893,12 +920,12 @@ class DateHelperTest < ActionView::TestCase
     expected << "</select>\n"
 
     assert_dom_equal expected, select_date(
-      Time.mktime(Date.today.year, 8, 16), :end_year => Date.today.year+1, :prefix => "date[first]"
+      Time.mktime(Date.today.year, 8, 16), end_year: Date.today.year + 1, prefix: "date[first]"
     )
   end
 
   def test_select_date_with_no_end_year
-    expected =  %(<select id="date_first_year" name="date[first][year]">\n)
+    expected = %(<select id="date_first_year" name="date[first][year]">\n).dup
     2003.upto(2008) do |y|
       if y == 2003
         expected << %(<option value="#{y}" selected="selected">#{y}</option>\n)
@@ -917,13 +944,13 @@ class DateHelperTest < ActionView::TestCase
     expected << "</select>\n"
 
     assert_dom_equal expected, select_date(
-      Time.mktime(2003, 8, 16), :start_year => 2003, :prefix => "date[first]"
+      Time.mktime(2003, 8, 16), start_year: 2003, prefix: "date[first]"
     )
   end
 
   def test_select_date_with_no_start_or_end_year
-    expected =  %(<select id="date_first_year" name="date[first][year]">\n)
-    (Date.today.year-5).upto(Date.today.year+5) do |y|
+    expected = %(<select id="date_first_year" name="date[first][year]">\n).dup
+    (Date.today.year - 5).upto(Date.today.year + 5) do |y|
       if y == Date.today.year
         expected << %(<option value="#{y}" selected="selected">#{y}</option>\n)
       else
@@ -941,12 +968,12 @@ class DateHelperTest < ActionView::TestCase
     expected << "</select>\n"
 
     assert_dom_equal expected, select_date(
-      Time.mktime(Date.today.year, 8, 16), :prefix => "date[first]"
+      Time.mktime(Date.today.year, 8, 16), prefix: "date[first]"
     )
   end
 
   def test_select_date_with_zero_value
-    expected =  %(<select id="date_first_year" name="date[first][year]">\n)
+    expected =  %(<select id="date_first_year" name="date[first][year]">\n).dup
     expected << %(<option value="2003">2003</option>\n<option value="2004">2004</option>\n<option value="2005">2005</option>\n)
     expected << "</select>\n"
 
@@ -958,12 +985,12 @@ class DateHelperTest < ActionView::TestCase
     expected << %(<option value="1">1</option>\n<option value="2">2</option>\n<option value="3">3</option>\n<option value="4">4</option>\n<option value="5">5</option>\n<option value="6">6</option>\n<option value="7">7</option>\n<option value="8">8</option>\n<option value="9">9</option>\n<option value="10">10</option>\n<option value="11">11</option>\n<option value="12">12</option>\n<option value="13">13</option>\n<option value="14">14</option>\n<option value="15">15</option>\n<option value="16">16</option>\n<option value="17">17</option>\n<option value="18">18</option>\n<option value="19">19</option>\n<option value="20">20</option>\n<option value="21">21</option>\n<option value="22">22</option>\n<option value="23">23</option>\n<option value="24">24</option>\n<option value="25">25</option>\n<option value="26">26</option>\n<option value="27">27</option>\n<option value="28">28</option>\n<option value="29">29</option>\n<option value="30">30</option>\n<option value="31">31</option>\n)
     expected << "</select>\n"
 
-    assert_dom_equal expected, select_date(0, :start_year => 2003, :end_year => 2005, :prefix => "date[first]")
+    assert_dom_equal expected, select_date(0, start_year: 2003, end_year: 2005, prefix: "date[first]")
   end
 
   def test_select_date_with_zero_value_and_no_start_year
-    expected =  %(<select id="date_first_year" name="date[first][year]">\n)
-    (Date.today.year-5).upto(Date.today.year+1) { |y| expected << %(<option value="#{y}">#{y}</option>\n) }
+    expected = %(<select id="date_first_year" name="date[first][year]">\n).dup
+    (Date.today.year - 5).upto(Date.today.year + 1) { |y| expected << %(<option value="#{y}">#{y}</option>\n) }
     expected << "</select>\n"
 
     expected << %(<select id="date_first_month" name="date[first][month]">\n)
@@ -974,11 +1001,11 @@ class DateHelperTest < ActionView::TestCase
     expected << %(<option value="1">1</option>\n<option value="2">2</option>\n<option value="3">3</option>\n<option value="4">4</option>\n<option value="5">5</option>\n<option value="6">6</option>\n<option value="7">7</option>\n<option value="8">8</option>\n<option value="9">9</option>\n<option value="10">10</option>\n<option value="11">11</option>\n<option value="12">12</option>\n<option value="13">13</option>\n<option value="14">14</option>\n<option value="15">15</option>\n<option value="16">16</option>\n<option value="17">17</option>\n<option value="18">18</option>\n<option value="19">19</option>\n<option value="20">20</option>\n<option value="21">21</option>\n<option value="22">22</option>\n<option value="23">23</option>\n<option value="24">24</option>\n<option value="25">25</option>\n<option value="26">26</option>\n<option value="27">27</option>\n<option value="28">28</option>\n<option value="29">29</option>\n<option value="30">30</option>\n<option value="31">31</option>\n)
     expected << "</select>\n"
 
-    assert_dom_equal expected, select_date(0, :end_year => Date.today.year+1, :prefix => "date[first]")
+    assert_dom_equal expected, select_date(0, end_year: Date.today.year + 1, prefix: "date[first]")
   end
 
   def test_select_date_with_zero_value_and_no_end_year
-    expected =  %(<select id="date_first_year" name="date[first][year]">\n)
+    expected =  %(<select id="date_first_year" name="date[first][year]">\n).dup
     last_year = Time.now.year + 5
     2003.upto(last_year) { |y| expected << %(<option value="#{y}">#{y}</option>\n) }
     expected << "</select>\n"
@@ -991,12 +1018,12 @@ class DateHelperTest < ActionView::TestCase
     expected << %(<option value="1">1</option>\n<option value="2">2</option>\n<option value="3">3</option>\n<option value="4">4</option>\n<option value="5">5</option>\n<option value="6">6</option>\n<option value="7">7</option>\n<option value="8">8</option>\n<option value="9">9</option>\n<option value="10">10</option>\n<option value="11">11</option>\n<option value="12">12</option>\n<option value="13">13</option>\n<option value="14">14</option>\n<option value="15">15</option>\n<option value="16">16</option>\n<option value="17">17</option>\n<option value="18">18</option>\n<option value="19">19</option>\n<option value="20">20</option>\n<option value="21">21</option>\n<option value="22">22</option>\n<option value="23">23</option>\n<option value="24">24</option>\n<option value="25">25</option>\n<option value="26">26</option>\n<option value="27">27</option>\n<option value="28">28</option>\n<option value="29">29</option>\n<option value="30">30</option>\n<option value="31">31</option>\n)
     expected << "</select>\n"
 
-    assert_dom_equal expected, select_date(0, :start_year => 2003, :prefix => "date[first]")
+    assert_dom_equal expected, select_date(0, start_year: 2003, prefix: "date[first]")
   end
 
   def test_select_date_with_zero_value_and_no_start_and_end_year
-    expected =  %(<select id="date_first_year" name="date[first][year]">\n)
-    (Date.today.year-5).upto(Date.today.year+5) { |y| expected << %(<option value="#{y}">#{y}</option>\n) }
+    expected = %(<select id="date_first_year" name="date[first][year]">\n).dup
+    (Date.today.year - 5).upto(Date.today.year + 5) { |y| expected << %(<option value="#{y}">#{y}</option>\n) }
     expected << "</select>\n"
 
     expected << %(<select id="date_first_month" name="date[first][month]">\n)
@@ -1007,12 +1034,12 @@ class DateHelperTest < ActionView::TestCase
     expected << %(<option value="1">1</option>\n<option value="2">2</option>\n<option value="3">3</option>\n<option value="4">4</option>\n<option value="5">5</option>\n<option value="6">6</option>\n<option value="7">7</option>\n<option value="8">8</option>\n<option value="9">9</option>\n<option value="10">10</option>\n<option value="11">11</option>\n<option value="12">12</option>\n<option value="13">13</option>\n<option value="14">14</option>\n<option value="15">15</option>\n<option value="16">16</option>\n<option value="17">17</option>\n<option value="18">18</option>\n<option value="19">19</option>\n<option value="20">20</option>\n<option value="21">21</option>\n<option value="22">22</option>\n<option value="23">23</option>\n<option value="24">24</option>\n<option value="25">25</option>\n<option value="26">26</option>\n<option value="27">27</option>\n<option value="28">28</option>\n<option value="29">29</option>\n<option value="30">30</option>\n<option value="31">31</option>\n)
     expected << "</select>\n"
 
-    assert_dom_equal expected, select_date(0, :prefix => "date[first]")
+    assert_dom_equal expected, select_date(0, prefix: "date[first]")
   end
 
   def test_select_date_with_nil_value_and_no_start_and_end_year
-    expected =  %(<select id="date_first_year" name="date[first][year]">\n)
-    (Date.today.year-5).upto(Date.today.year+5) { |y| expected << %(<option value="#{y}">#{y}</option>\n) }
+    expected = %(<select id="date_first_year" name="date[first][year]">\n).dup
+    (Date.today.year - 5).upto(Date.today.year + 5) { |y| expected << %(<option value="#{y}">#{y}</option>\n) }
     expected << "</select>\n"
 
     expected << %(<select id="date_first_month" name="date[first][month]">\n)
@@ -1023,11 +1050,11 @@ class DateHelperTest < ActionView::TestCase
     expected << %(<option value="1">1</option>\n<option value="2">2</option>\n<option value="3">3</option>\n<option value="4">4</option>\n<option value="5">5</option>\n<option value="6">6</option>\n<option value="7">7</option>\n<option value="8">8</option>\n<option value="9">9</option>\n<option value="10">10</option>\n<option value="11">11</option>\n<option value="12">12</option>\n<option value="13">13</option>\n<option value="14">14</option>\n<option value="15">15</option>\n<option value="16">16</option>\n<option value="17">17</option>\n<option value="18">18</option>\n<option value="19">19</option>\n<option value="20">20</option>\n<option value="21">21</option>\n<option value="22">22</option>\n<option value="23">23</option>\n<option value="24">24</option>\n<option value="25">25</option>\n<option value="26">26</option>\n<option value="27">27</option>\n<option value="28">28</option>\n<option value="29">29</option>\n<option value="30">30</option>\n<option value="31">31</option>\n)
     expected << "</select>\n"
 
-    assert_dom_equal expected, select_date(nil, :prefix => "date[first]")
+    assert_dom_equal expected, select_date(nil, prefix: "date[first]")
   end
 
   def test_select_date_with_html_options
-    expected =  %(<select id="date_first_year" name="date[first][year]" class="selector">\n)
+    expected =  %(<select id="date_first_year" name="date[first][year]" class="selector">\n).dup
     expected << %(<option value="2003" selected="selected">2003</option>\n<option value="2004">2004</option>\n<option value="2005">2005</option>\n)
     expected << "</select>\n"
 
@@ -1039,11 +1066,11 @@ class DateHelperTest < ActionView::TestCase
     expected << %(<option value="1">1</option>\n<option value="2">2</option>\n<option value="3">3</option>\n<option value="4">4</option>\n<option value="5">5</option>\n<option value="6">6</option>\n<option value="7">7</option>\n<option value="8">8</option>\n<option value="9">9</option>\n<option value="10">10</option>\n<option value="11">11</option>\n<option value="12">12</option>\n<option value="13">13</option>\n<option value="14">14</option>\n<option value="15">15</option>\n<option value="16" selected="selected">16</option>\n<option value="17">17</option>\n<option value="18">18</option>\n<option value="19">19</option>\n<option value="20">20</option>\n<option value="21">21</option>\n<option value="22">22</option>\n<option value="23">23</option>\n<option value="24">24</option>\n<option value="25">25</option>\n<option value="26">26</option>\n<option value="27">27</option>\n<option value="28">28</option>\n<option value="29">29</option>\n<option value="30">30</option>\n<option value="31">31</option>\n)
     expected << "</select>\n"
 
-    assert_dom_equal expected, select_date(Time.mktime(2003, 8, 16), {:start_year => 2003, :end_year => 2005, :prefix => "date[first]"}, :class => "selector")
+    assert_dom_equal expected, select_date(Time.mktime(2003, 8, 16), { start_year: 2003, end_year: 2005, prefix: "date[first]" }, { class: "selector" })
   end
 
   def test_select_date_with_separator
-    expected =  %(<select id="date_first_year" name="date[first][year]">\n)
+    expected =  %(<select id="date_first_year" name="date[first][year]">\n).dup
     expected << %(<option value="2003" selected="selected">2003</option>\n<option value="2004">2004</option>\n<option value="2005">2005</option>\n)
     expected << "</select>\n"
 
@@ -1059,11 +1086,11 @@ class DateHelperTest < ActionView::TestCase
     expected << %(<option value="1">1</option>\n<option value="2">2</option>\n<option value="3">3</option>\n<option value="4">4</option>\n<option value="5">5</option>\n<option value="6">6</option>\n<option value="7">7</option>\n<option value="8">8</option>\n<option value="9">9</option>\n<option value="10">10</option>\n<option value="11">11</option>\n<option value="12">12</option>\n<option value="13">13</option>\n<option value="14">14</option>\n<option value="15">15</option>\n<option value="16" selected="selected">16</option>\n<option value="17">17</option>\n<option value="18">18</option>\n<option value="19">19</option>\n<option value="20">20</option>\n<option value="21">21</option>\n<option value="22">22</option>\n<option value="23">23</option>\n<option value="24">24</option>\n<option value="25">25</option>\n<option value="26">26</option>\n<option value="27">27</option>\n<option value="28">28</option>\n<option value="29">29</option>\n<option value="30">30</option>\n<option value="31">31</option>\n)
     expected << "</select>\n"
 
-    assert_dom_equal expected, select_date(Time.mktime(2003, 8, 16), { :date_separator => " / ", :start_year => 2003, :end_year => 2005, :prefix => "date[first]"})
+    assert_dom_equal expected, select_date(Time.mktime(2003, 8, 16), date_separator: " / ", start_year: 2003, end_year: 2005, prefix: "date[first]")
   end
 
   def test_select_date_with_separator_and_discard_day
-    expected =  %(<select id="date_first_year" name="date[first][year]">\n)
+    expected =  %(<select id="date_first_year" name="date[first][year]">\n).dup
     expected << %(<option value="2003" selected="selected">2003</option>\n<option value="2004">2004</option>\n<option value="2005">2005</option>\n)
     expected << "</select>\n"
 
@@ -1075,31 +1102,31 @@ class DateHelperTest < ActionView::TestCase
 
     expected << %(<input type="hidden" id="date_first_day" name="date[first][day]" value="1" />\n)
 
-    assert_dom_equal expected, select_date(Time.mktime(2003, 8, 16), { :date_separator => " / ", :discard_day => true, :start_year => 2003, :end_year => 2005, :prefix => "date[first]"})
+    assert_dom_equal expected, select_date(Time.mktime(2003, 8, 16), date_separator: " / ", discard_day: true, start_year: 2003, end_year: 2005, prefix: "date[first]")
   end
 
   def test_select_date_with_separator_discard_month_and_day
-    expected =  %(<select id="date_first_year" name="date[first][year]">\n)
+    expected =  %(<select id="date_first_year" name="date[first][year]">\n).dup
     expected << %(<option value="2003" selected="selected">2003</option>\n<option value="2004">2004</option>\n<option value="2005">2005</option>\n)
     expected << "</select>\n"
 
     expected << %(<input type="hidden" id="date_first_month" name="date[first][month]" value="8" />\n)
     expected << %(<input type="hidden" id="date_first_day" name="date[first][day]" value="1" />\n)
 
-    assert_dom_equal expected, select_date(Time.mktime(2003, 8, 16), { :date_separator => " / ", :discard_month => true, :discard_day => true, :start_year => 2003, :end_year => 2005, :prefix => "date[first]"})
+    assert_dom_equal expected, select_date(Time.mktime(2003, 8, 16), date_separator: " / ", discard_month: true, discard_day: true, start_year: 2003, end_year: 2005, prefix: "date[first]")
   end
 
   def test_select_date_with_hidden
-    expected =  %(<input id="date_first_year" name="date[first][year]" type="hidden" value="2003"/>\n)
+    expected =  %(<input id="date_first_year" name="date[first][year]" type="hidden" value="2003"/>\n).dup
     expected << %(<input id="date_first_month" name="date[first][month]" type="hidden" value="8" />\n)
     expected << %(<input id="date_first_day" name="date[first][day]" type="hidden" value="16" />\n)
 
-    assert_dom_equal expected, select_date(Time.mktime(2003, 8, 16), { :prefix => "date[first]", :use_hidden => true })
-    assert_dom_equal expected, select_date(Time.mktime(2003, 8, 16), { :date_separator => " / ", :prefix => "date[first]", :use_hidden => true })
+    assert_dom_equal expected, select_date(Time.mktime(2003, 8, 16), prefix: "date[first]", use_hidden: true)
+    assert_dom_equal expected, select_date(Time.mktime(2003, 8, 16), date_separator: " / ", prefix: "date[first]", use_hidden: true)
   end
 
   def test_select_date_with_css_classes_option
-    expected =  %(<select id="date_first_year" name="date[first][year]" class="year">\n)
+    expected =  %(<select id="date_first_year" name="date[first][year]" class="year">\n).dup
     expected << %(<option value="2003" selected="selected">2003</option>\n<option value="2004">2004</option>\n<option value="2005">2005</option>\n)
     expected << "</select>\n"
 
@@ -1111,11 +1138,11 @@ class DateHelperTest < ActionView::TestCase
     expected << %(<option value="1">1</option>\n<option value="2">2</option>\n<option value="3">3</option>\n<option value="4">4</option>\n<option value="5">5</option>\n<option value="6">6</option>\n<option value="7">7</option>\n<option value="8">8</option>\n<option value="9">9</option>\n<option value="10">10</option>\n<option value="11">11</option>\n<option value="12">12</option>\n<option value="13">13</option>\n<option value="14">14</option>\n<option value="15">15</option>\n<option value="16" selected="selected">16</option>\n<option value="17">17</option>\n<option value="18">18</option>\n<option value="19">19</option>\n<option value="20">20</option>\n<option value="21">21</option>\n<option value="22">22</option>\n<option value="23">23</option>\n<option value="24">24</option>\n<option value="25">25</option>\n<option value="26">26</option>\n<option value="27">27</option>\n<option value="28">28</option>\n<option value="29">29</option>\n<option value="30">30</option>\n<option value="31">31</option>\n)
     expected << "</select>\n"
 
-    assert_dom_equal expected, select_date(Time.mktime(2003, 8, 16), {:start_year => 2003, :end_year => 2005, :prefix => "date[first]", :with_css_classes => true})
+    assert_dom_equal expected, select_date(Time.mktime(2003, 8, 16), start_year: 2003, end_year: 2005, prefix: "date[first]", with_css_classes: true)
   end
 
   def test_select_date_with_custom_with_css_classes
-    expected =  %(<select id="date_year" name="date[year]" class="my-year">\n)
+    expected =  %(<select id="date_year" name="date[year]" class="my-year">\n).dup
     expected << %(<option value="2003" selected="selected">2003</option>\n<option value="2004">2004</option>\n<option value="2005">2005</option>\n)
     expected << "</select>\n"
 
@@ -1127,11 +1154,11 @@ class DateHelperTest < ActionView::TestCase
     expected << %(<option value="1">1</option>\n<option value="2">2</option>\n<option value="3">3</option>\n<option value="4">4</option>\n<option value="5">5</option>\n<option value="6">6</option>\n<option value="7">7</option>\n<option value="8">8</option>\n<option value="9">9</option>\n<option value="10">10</option>\n<option value="11">11</option>\n<option value="12">12</option>\n<option value="13">13</option>\n<option value="14">14</option>\n<option value="15">15</option>\n<option value="16" selected="selected">16</option>\n<option value="17">17</option>\n<option value="18">18</option>\n<option value="19">19</option>\n<option value="20">20</option>\n<option value="21">21</option>\n<option value="22">22</option>\n<option value="23">23</option>\n<option value="24">24</option>\n<option value="25">25</option>\n<option value="26">26</option>\n<option value="27">27</option>\n<option value="28">28</option>\n<option value="29">29</option>\n<option value="30">30</option>\n<option value="31">31</option>\n)
     expected << "</select>\n"
 
-    assert_dom_equal expected, select_date(Time.mktime(2003, 8, 16), start_year: 2003, end_year: 2005, with_css_classes: { year: 'my-year', month: 'my-month', day: 'my-day' })
+    assert_dom_equal expected, select_date(Time.mktime(2003, 8, 16), start_year: 2003, end_year: 2005, with_css_classes: { year: "my-year", month: "my-month", day: "my-day" })
   end
 
   def test_select_date_with_css_classes_option_and_html_class_option
-    expected =  %(<select id="date_first_year" name="date[first][year]" class="datetime optional year">\n)
+    expected =  %(<select id="date_first_year" name="date[first][year]" class="datetime optional year">\n).dup
     expected << %(<option value="2003" selected="selected">2003</option>\n<option value="2004">2004</option>\n<option value="2005">2005</option>\n)
     expected << "</select>\n"
 
@@ -1143,11 +1170,11 @@ class DateHelperTest < ActionView::TestCase
     expected << %(<option value="1">1</option>\n<option value="2">2</option>\n<option value="3">3</option>\n<option value="4">4</option>\n<option value="5">5</option>\n<option value="6">6</option>\n<option value="7">7</option>\n<option value="8">8</option>\n<option value="9">9</option>\n<option value="10">10</option>\n<option value="11">11</option>\n<option value="12">12</option>\n<option value="13">13</option>\n<option value="14">14</option>\n<option value="15">15</option>\n<option value="16" selected="selected">16</option>\n<option value="17">17</option>\n<option value="18">18</option>\n<option value="19">19</option>\n<option value="20">20</option>\n<option value="21">21</option>\n<option value="22">22</option>\n<option value="23">23</option>\n<option value="24">24</option>\n<option value="25">25</option>\n<option value="26">26</option>\n<option value="27">27</option>\n<option value="28">28</option>\n<option value="29">29</option>\n<option value="30">30</option>\n<option value="31">31</option>\n)
     expected << "</select>\n"
 
-    assert_dom_equal expected, select_date(Time.mktime(2003, 8, 16), {:start_year => 2003, :end_year => 2005, :prefix => "date[first]", :with_css_classes => true}, { class: 'datetime optional' })
+    assert_dom_equal expected, select_date(Time.mktime(2003, 8, 16), { start_year: 2003, end_year: 2005, prefix: "date[first]", with_css_classes: true }, { class: "datetime optional" })
   end
 
   def test_select_date_with_custom_with_css_classes_and_html_class_option
-    expected =  %(<select id="date_year" name="date[year]" class="date optional my-year">\n)
+    expected =  %(<select id="date_year" name="date[year]" class="date optional my-year">\n).dup
     expected << %(<option value="2003" selected="selected">2003</option>\n<option value="2004">2004</option>\n<option value="2005">2005</option>\n)
     expected << "</select>\n"
 
@@ -1159,11 +1186,11 @@ class DateHelperTest < ActionView::TestCase
     expected << %(<option value="1">1</option>\n<option value="2">2</option>\n<option value="3">3</option>\n<option value="4">4</option>\n<option value="5">5</option>\n<option value="6">6</option>\n<option value="7">7</option>\n<option value="8">8</option>\n<option value="9">9</option>\n<option value="10">10</option>\n<option value="11">11</option>\n<option value="12">12</option>\n<option value="13">13</option>\n<option value="14">14</option>\n<option value="15">15</option>\n<option value="16" selected="selected">16</option>\n<option value="17">17</option>\n<option value="18">18</option>\n<option value="19">19</option>\n<option value="20">20</option>\n<option value="21">21</option>\n<option value="22">22</option>\n<option value="23">23</option>\n<option value="24">24</option>\n<option value="25">25</option>\n<option value="26">26</option>\n<option value="27">27</option>\n<option value="28">28</option>\n<option value="29">29</option>\n<option value="30">30</option>\n<option value="31">31</option>\n)
     expected << "</select>\n"
 
-    assert_dom_equal expected, select_date(Time.mktime(2003, 8, 16), {start_year: 2003, end_year: 2005, with_css_classes: { year: 'my-year', month: 'my-month', day: 'my-day' }}, { class: 'date optional' })
+    assert_dom_equal expected, select_date(Time.mktime(2003, 8, 16), { start_year: 2003, end_year: 2005, with_css_classes: { year: "my-year", month: "my-month", day: "my-day" } }, { class: "date optional" })
   end
 
   def test_select_date_with_partial_with_css_classes_and_html_class_option
-    expected =  %(<select id="date_year" name="date[year]" class="date optional">\n)
+    expected =  %(<select id="date_year" name="date[year]" class="date optional">\n).dup
     expected << %(<option value="2003" selected="selected">2003</option>\n<option value="2004">2004</option>\n<option value="2005">2005</option>\n)
     expected << "</select>\n"
 
@@ -1175,11 +1202,11 @@ class DateHelperTest < ActionView::TestCase
     expected << %(<option value="1">1</option>\n<option value="2">2</option>\n<option value="3">3</option>\n<option value="4">4</option>\n<option value="5">5</option>\n<option value="6">6</option>\n<option value="7">7</option>\n<option value="8">8</option>\n<option value="9">9</option>\n<option value="10">10</option>\n<option value="11">11</option>\n<option value="12">12</option>\n<option value="13">13</option>\n<option value="14">14</option>\n<option value="15">15</option>\n<option value="16" selected="selected">16</option>\n<option value="17">17</option>\n<option value="18">18</option>\n<option value="19">19</option>\n<option value="20">20</option>\n<option value="21">21</option>\n<option value="22">22</option>\n<option value="23">23</option>\n<option value="24">24</option>\n<option value="25">25</option>\n<option value="26">26</option>\n<option value="27">27</option>\n<option value="28">28</option>\n<option value="29">29</option>\n<option value="30">30</option>\n<option value="31">31</option>\n)
     expected << "</select>\n"
 
-    assert_dom_equal expected, select_date(Time.mktime(2003, 8, 16), {start_year: 2003, end_year: 2005, with_css_classes: { month: 'my-month custom-grid' }}, { class: 'date optional' })
+    assert_dom_equal expected, select_date(Time.mktime(2003, 8, 16), { start_year: 2003, end_year: 2005, with_css_classes: { month: "my-month custom-grid" } }, { class: "date optional" })
   end
 
   def test_select_date_with_html_class_option
-    expected =  %(<select id="date_year" name="date[year]" class="date optional custom-grid">\n)
+    expected =  %(<select id="date_year" name="date[year]" class="date optional custom-grid">\n).dup
     expected << %(<option value="2003" selected="selected">2003</option>\n<option value="2004">2004</option>\n<option value="2005">2005</option>\n)
     expected << "</select>\n"
 
@@ -1191,11 +1218,11 @@ class DateHelperTest < ActionView::TestCase
     expected << %(<option value="1">1</option>\n<option value="2">2</option>\n<option value="3">3</option>\n<option value="4">4</option>\n<option value="5">5</option>\n<option value="6">6</option>\n<option value="7">7</option>\n<option value="8">8</option>\n<option value="9">9</option>\n<option value="10">10</option>\n<option value="11">11</option>\n<option value="12">12</option>\n<option value="13">13</option>\n<option value="14">14</option>\n<option value="15">15</option>\n<option value="16" selected="selected">16</option>\n<option value="17">17</option>\n<option value="18">18</option>\n<option value="19">19</option>\n<option value="20">20</option>\n<option value="21">21</option>\n<option value="22">22</option>\n<option value="23">23</option>\n<option value="24">24</option>\n<option value="25">25</option>\n<option value="26">26</option>\n<option value="27">27</option>\n<option value="28">28</option>\n<option value="29">29</option>\n<option value="30">30</option>\n<option value="31">31</option>\n)
     expected << "</select>\n"
 
-    assert_dom_equal expected, select_date(Time.mktime(2003, 8, 16), { start_year: 2003, end_year: 2005 }, { class: 'date optional custom-grid' })
+    assert_dom_equal expected, select_date(Time.mktime(2003, 8, 16), { start_year: 2003, end_year: 2005 }, { class: "date optional custom-grid" })
   end
 
   def test_select_datetime
-    expected =  %(<select id="date_first_year" name="date[first][year]">\n)
+    expected =  %(<select id="date_first_year" name="date[first][year]">\n).dup
     expected << %(<option value="2003" selected="selected">2003</option>\n<option value="2004">2004</option>\n<option value="2005">2005</option>\n)
     expected << "</select>\n"
 
@@ -1219,11 +1246,11 @@ class DateHelperTest < ActionView::TestCase
     expected << %(<option value="00">00</option>\n<option value="01">01</option>\n<option value="02">02</option>\n<option value="03">03</option>\n<option value="04" selected="selected">04</option>\n<option value="05">05</option>\n<option value="06">06</option>\n<option value="07">07</option>\n<option value="08">08</option>\n<option value="09">09</option>\n<option value="10">10</option>\n<option value="11">11</option>\n<option value="12">12</option>\n<option value="13">13</option>\n<option value="14">14</option>\n<option value="15">15</option>\n<option value="16">16</option>\n<option value="17">17</option>\n<option value="18">18</option>\n<option value="19">19</option>\n<option value="20">20</option>\n<option value="21">21</option>\n<option value="22">22</option>\n<option value="23">23</option>\n<option value="24">24</option>\n<option value="25">25</option>\n<option value="26">26</option>\n<option value="27">27</option>\n<option value="28">28</option>\n<option value="29">29</option>\n<option value="30">30</option>\n<option value="31">31</option>\n<option value="32">32</option>\n<option value="33">33</option>\n<option value="34">34</option>\n<option value="35">35</option>\n<option value="36">36</option>\n<option value="37">37</option>\n<option value="38">38</option>\n<option value="39">39</option>\n<option value="40">40</option>\n<option value="41">41</option>\n<option value="42">42</option>\n<option value="43">43</option>\n<option value="44">44</option>\n<option value="45">45</option>\n<option value="46">46</option>\n<option value="47">47</option>\n<option value="48">48</option>\n<option value="49">49</option>\n<option value="50">50</option>\n<option value="51">51</option>\n<option value="52">52</option>\n<option value="53">53</option>\n<option value="54">54</option>\n<option value="55">55</option>\n<option value="56">56</option>\n<option value="57">57</option>\n<option value="58">58</option>\n<option value="59">59</option>\n)
     expected << "</select>\n"
 
-    assert_dom_equal expected, select_datetime(Time.mktime(2003, 8, 16, 8, 4, 18), :start_year => 2003, :end_year => 2005, :prefix => "date[first]")
+    assert_dom_equal expected, select_datetime(Time.mktime(2003, 8, 16, 8, 4, 18), start_year: 2003, end_year: 2005, prefix: "date[first]")
   end
 
   def test_select_datetime_with_ampm
-    expected =  %(<select id="date_first_year" name="date[first][year]">\n)
+    expected =  %(<select id="date_first_year" name="date[first][year]">\n).dup
     expected << %(<option value="2003" selected="selected">2003</option>\n<option value="2004">2004</option>\n<option value="2005">2005</option>\n)
     expected << "</select>\n"
 
@@ -1247,11 +1274,11 @@ class DateHelperTest < ActionView::TestCase
     expected << %(<option value="00">00</option>\n<option value="01">01</option>\n<option value="02">02</option>\n<option value="03">03</option>\n<option value="04" selected="selected">04</option>\n<option value="05">05</option>\n<option value="06">06</option>\n<option value="07">07</option>\n<option value="08">08</option>\n<option value="09">09</option>\n<option value="10">10</option>\n<option value="11">11</option>\n<option value="12">12</option>\n<option value="13">13</option>\n<option value="14">14</option>\n<option value="15">15</option>\n<option value="16">16</option>\n<option value="17">17</option>\n<option value="18">18</option>\n<option value="19">19</option>\n<option value="20">20</option>\n<option value="21">21</option>\n<option value="22">22</option>\n<option value="23">23</option>\n<option value="24">24</option>\n<option value="25">25</option>\n<option value="26">26</option>\n<option value="27">27</option>\n<option value="28">28</option>\n<option value="29">29</option>\n<option value="30">30</option>\n<option value="31">31</option>\n<option value="32">32</option>\n<option value="33">33</option>\n<option value="34">34</option>\n<option value="35">35</option>\n<option value="36">36</option>\n<option value="37">37</option>\n<option value="38">38</option>\n<option value="39">39</option>\n<option value="40">40</option>\n<option value="41">41</option>\n<option value="42">42</option>\n<option value="43">43</option>\n<option value="44">44</option>\n<option value="45">45</option>\n<option value="46">46</option>\n<option value="47">47</option>\n<option value="48">48</option>\n<option value="49">49</option>\n<option value="50">50</option>\n<option value="51">51</option>\n<option value="52">52</option>\n<option value="53">53</option>\n<option value="54">54</option>\n<option value="55">55</option>\n<option value="56">56</option>\n<option value="57">57</option>\n<option value="58">58</option>\n<option value="59">59</option>\n)
     expected << "</select>\n"
 
-    assert_dom_equal expected, select_datetime(Time.mktime(2003, 8, 16, 8, 4, 18), :start_year => 2003, :end_year => 2005, :prefix => "date[first]", :ampm => true)
+    assert_dom_equal expected, select_datetime(Time.mktime(2003, 8, 16, 8, 4, 18), start_year: 2003, end_year: 2005, prefix: "date[first]", ampm: true)
   end
 
   def test_select_datetime_with_separators
-    expected =  %(<select id="date_first_year" name="date[first][year]">\n)
+    expected =  %(<select id="date_first_year" name="date[first][year]">\n).dup
     expected << %(<option value="2003" selected="selected">2003</option>\n<option value="2004">2004</option>\n<option value="2005">2005</option>\n)
     expected << "</select>\n"
 
@@ -1275,12 +1302,12 @@ class DateHelperTest < ActionView::TestCase
     expected << %(<option value="00">00</option>\n<option value="01">01</option>\n<option value="02">02</option>\n<option value="03">03</option>\n<option value="04" selected="selected">04</option>\n<option value="05">05</option>\n<option value="06">06</option>\n<option value="07">07</option>\n<option value="08">08</option>\n<option value="09">09</option>\n<option value="10">10</option>\n<option value="11">11</option>\n<option value="12">12</option>\n<option value="13">13</option>\n<option value="14">14</option>\n<option value="15">15</option>\n<option value="16">16</option>\n<option value="17">17</option>\n<option value="18">18</option>\n<option value="19">19</option>\n<option value="20">20</option>\n<option value="21">21</option>\n<option value="22">22</option>\n<option value="23">23</option>\n<option value="24">24</option>\n<option value="25">25</option>\n<option value="26">26</option>\n<option value="27">27</option>\n<option value="28">28</option>\n<option value="29">29</option>\n<option value="30">30</option>\n<option value="31">31</option>\n<option value="32">32</option>\n<option value="33">33</option>\n<option value="34">34</option>\n<option value="35">35</option>\n<option value="36">36</option>\n<option value="37">37</option>\n<option value="38">38</option>\n<option value="39">39</option>\n<option value="40">40</option>\n<option value="41">41</option>\n<option value="42">42</option>\n<option value="43">43</option>\n<option value="44">44</option>\n<option value="45">45</option>\n<option value="46">46</option>\n<option value="47">47</option>\n<option value="48">48</option>\n<option value="49">49</option>\n<option value="50">50</option>\n<option value="51">51</option>\n<option value="52">52</option>\n<option value="53">53</option>\n<option value="54">54</option>\n<option value="55">55</option>\n<option value="56">56</option>\n<option value="57">57</option>\n<option value="58">58</option>\n<option value="59">59</option>\n)
     expected << "</select>\n"
 
-    assert_dom_equal expected, select_datetime(Time.mktime(2003, 8, 16, 8, 4, 18), :start_year => 2003, :end_year => 2005, :prefix => "date[first]", :datetime_separator => ' &mdash; ', :time_separator => ' : ')
+    assert_dom_equal expected, select_datetime(Time.mktime(2003, 8, 16, 8, 4, 18), start_year: 2003, end_year: 2005, prefix: "date[first]", datetime_separator: " &mdash; ", time_separator: " : ")
   end
 
   def test_select_datetime_with_nil_value_and_no_start_and_end_year
-    expected =  %(<select id="date_first_year" name="date[first][year]">\n)
-    (Date.today.year-5).upto(Date.today.year+5) { |y| expected << %(<option value="#{y}">#{y}</option>\n) }
+    expected = %(<select id="date_first_year" name="date[first][year]">\n).dup
+    (Date.today.year - 5).upto(Date.today.year + 5) { |y| expected << %(<option value="#{y}">#{y}</option>\n) }
     expected << "</select>\n"
 
     expected << %(<select id="date_first_month" name="date[first][month]">\n)
@@ -1303,15 +1330,14 @@ class DateHelperTest < ActionView::TestCase
     expected << %(<option value="00">00</option>\n<option value="01">01</option>\n<option value="02">02</option>\n<option value="03">03</option>\n<option value="04">04</option>\n<option value="05">05</option>\n<option value="06">06</option>\n<option value="07">07</option>\n<option value="08">08</option>\n<option value="09">09</option>\n<option value="10">10</option>\n<option value="11">11</option>\n<option value="12">12</option>\n<option value="13">13</option>\n<option value="14">14</option>\n<option value="15">15</option>\n<option value="16">16</option>\n<option value="17">17</option>\n<option value="18">18</option>\n<option value="19">19</option>\n<option value="20">20</option>\n<option value="21">21</option>\n<option value="22">22</option>\n<option value="23">23</option>\n<option value="24">24</option>\n<option value="25">25</option>\n<option value="26">26</option>\n<option value="27">27</option>\n<option value="28">28</option>\n<option value="29">29</option>\n<option value="30">30</option>\n<option value="31">31</option>\n<option value="32">32</option>\n<option value="33">33</option>\n<option value="34">34</option>\n<option value="35">35</option>\n<option value="36">36</option>\n<option value="37">37</option>\n<option value="38">38</option>\n<option value="39">39</option>\n<option value="40">40</option>\n<option value="41">41</option>\n<option value="42">42</option>\n<option value="43">43</option>\n<option value="44">44</option>\n<option value="45">45</option>\n<option value="46">46</option>\n<option value="47">47</option>\n<option value="48">48</option>\n<option value="49">49</option>\n<option value="50">50</option>\n<option value="51">51</option>\n<option value="52">52</option>\n<option value="53">53</option>\n<option value="54">54</option>\n<option value="55">55</option>\n<option value="56">56</option>\n<option value="57">57</option>\n<option value="58">58</option>\n<option value="59">59</option>\n)
     expected << "</select>\n"
 
-    assert_dom_equal expected, select_datetime(nil, :prefix => "date[first]")
+    assert_dom_equal expected, select_datetime(nil, prefix: "date[first]")
   end
 
   def test_select_datetime_with_html_options
-    expected =  %(<select id="date_first_year" name="date[first][year]" class="selector">\n)
+    expected =  %(<select id="date_first_year" name="date[first][year]" class="selector">\n).dup
     expected << %(<option value="2003" selected="selected">2003</option>\n<option value="2004">2004</option>\n<option value="2005">2005</option>\n)
     expected << "</select>\n"
 
-
     expected << %(<select id="date_first_month" name="date[first][month]" class="selector">\n)
     expected << %(<option value="1">January</option>\n<option value="2">February</option>\n<option value="3">March</option>\n<option value="4">April</option>\n<option value="5">May</option>\n<option value="6">June</option>\n<option value="7">July</option>\n<option value="8" selected="selected">August</option>\n<option value="9">September</option>\n<option value="10">October</option>\n<option value="11">November</option>\n<option value="12">December</option>\n)
     expected << "</select>\n"
@@ -1332,11 +1358,11 @@ class DateHelperTest < ActionView::TestCase
     expected << %(<option value="00">00</option>\n<option value="01">01</option>\n<option value="02">02</option>\n<option value="03">03</option>\n<option value="04" selected="selected">04</option>\n<option value="05">05</option>\n<option value="06">06</option>\n<option value="07">07</option>\n<option value="08">08</option>\n<option value="09">09</option>\n<option value="10">10</option>\n<option value="11">11</option>\n<option value="12">12</option>\n<option value="13">13</option>\n<option value="14">14</option>\n<option value="15">15</option>\n<option value="16">16</option>\n<option value="17">17</option>\n<option value="18">18</option>\n<option value="19">19</option>\n<option value="20">20</option>\n<option value="21">21</option>\n<option value="22">22</option>\n<option value="23">23</option>\n<option value="24">24</option>\n<option value="25">25</option>\n<option value="26">26</option>\n<option value="27">27</option>\n<option value="28">28</option>\n<option value="29">29</option>\n<option value="30">30</option>\n<option value="31">31</option>\n<option value="32">32</option>\n<option value="33">33</option>\n<option value="34">34</option>\n<option value="35">35</option>\n<option value="36">36</option>\n<option value="37">37</option>\n<option value="38">38</option>\n<option value="39">39</option>\n<option value="40">40</option>\n<option value="41">41</option>\n<option value="42">42</option>\n<option value="43">43</option>\n<option value="44">44</option>\n<option value="45">45</option>\n<option value="46">46</option>\n<option value="47">47</option>\n<option value="48">48</option>\n<option value="49">49</option>\n<option value="50">50</option>\n<option value="51">51</option>\n<option value="52">52</option>\n<option value="53">53</option>\n<option value="54">54</option>\n<option value="55">55</option>\n<option value="56">56</option>\n<option value="57">57</option>\n<option value="58">58</option>\n<option value="59">59</option>\n)
     expected << "</select>\n"
 
-    assert_dom_equal expected, select_datetime(Time.mktime(2003, 8, 16, 8, 4, 18), {:start_year => 2003, :end_year => 2005, :prefix => "date[first]"}, :class => 'selector')
+    assert_dom_equal expected, select_datetime(Time.mktime(2003, 8, 16, 8, 4, 18), { start_year: 2003, end_year: 2005, prefix: "date[first]" }, { class: "selector" })
   end
 
   def test_select_datetime_with_all_separators
-    expected =  %(<select id="date_first_year" name="date[first][year]" class="selector">\n)
+    expected =  %(<select id="date_first_year" name="date[first][year]" class="selector">\n).dup
     expected << %(<option value="2003" selected="selected">2003</option>\n<option value="2004">2004</option>\n<option value="2005">2005</option>\n)
     expected << "</select>\n"
 
@@ -1364,7 +1390,7 @@ class DateHelperTest < ActionView::TestCase
     expected << %(<option value="00">00</option>\n<option value="01">01</option>\n<option value="02">02</option>\n<option value="03">03</option>\n<option value="04" selected="selected">04</option>\n<option value="05">05</option>\n<option value="06">06</option>\n<option value="07">07</option>\n<option value="08">08</option>\n<option value="09">09</option>\n<option value="10">10</option>\n<option value="11">11</option>\n<option value="12">12</option>\n<option value="13">13</option>\n<option value="14">14</option>\n<option value="15">15</option>\n<option value="16">16</option>\n<option value="17">17</option>\n<option value="18">18</option>\n<option value="19">19</option>\n<option value="20">20</option>\n<option value="21">21</option>\n<option value="22">22</option>\n<option value="23">23</option>\n<option value="24">24</option>\n<option value="25">25</option>\n<option value="26">26</option>\n<option value="27">27</option>\n<option value="28">28</option>\n<option value="29">29</option>\n<option value="30">30</option>\n<option value="31">31</option>\n<option value="32">32</option>\n<option value="33">33</option>\n<option value="34">34</option>\n<option value="35">35</option>\n<option value="36">36</option>\n<option value="37">37</option>\n<option value="38">38</option>\n<option value="39">39</option>\n<option value="40">40</option>\n<option value="41">41</option>\n<option value="42">42</option>\n<option value="43">43</option>\n<option value="44">44</option>\n<option value="45">45</option>\n<option value="46">46</option>\n<option value="47">47</option>\n<option value="48">48</option>\n<option value="49">49</option>\n<option value="50">50</option>\n<option value="51">51</option>\n<option value="52">52</option>\n<option value="53">53</option>\n<option value="54">54</option>\n<option value="55">55</option>\n<option value="56">56</option>\n<option value="57">57</option>\n<option value="58">58</option>\n<option value="59">59</option>\n)
     expected << "</select>\n"
 
-    assert_dom_equal expected, select_datetime(Time.mktime(2003, 8, 16, 8, 4, 18), { :datetime_separator => "&mdash;", :date_separator => "/", :time_separator => ":", :start_year => 2003, :end_year => 2005, :prefix => "date[first]"}, :class => 'selector')
+    assert_dom_equal expected, select_datetime(Time.mktime(2003, 8, 16, 8, 4, 18), { datetime_separator: "&mdash;", date_separator: "/", time_separator: ":", start_year: 2003, end_year: 2005, prefix: "date[first]" }, { class: "selector" })
   end
 
   def test_select_datetime_should_work_with_date
@@ -1372,7 +1398,7 @@ class DateHelperTest < ActionView::TestCase
   end
 
   def test_select_datetime_with_default_prompt
-    expected =  %(<select id="date_first_year" name="date[first][year]">\n)
+    expected =  %(<select id="date_first_year" name="date[first][year]">\n).dup
     expected << %(<option value="">Year</option>\n<option value="2003" selected="selected">2003</option>\n<option value="2004">2004</option>\n<option value="2005">2005</option>\n)
     expected << "</select>\n"
 
@@ -1396,13 +1422,12 @@ class DateHelperTest < ActionView::TestCase
     expected << %(<option value="">Minute</option>\n<option value="00">00</option>\n<option value="01">01</option>\n<option value="02">02</option>\n<option value="03">03</option>\n<option value="04" selected="selected">04</option>\n<option value="05">05</option>\n<option value="06">06</option>\n<option value="07">07</option>\n<option value="08">08</option>\n<option value="09">09</option>\n<option value="10">10</option>\n<option value="11">11</option>\n<option value="12">12</option>\n<option value="13">13</option>\n<option value="14">14</option>\n<option value="15">15</option>\n<option value="16">16</option>\n<option value="17">17</option>\n<option value="18">18</option>\n<option value="19">19</option>\n<option value="20">20</option>\n<option value="21">21</option>\n<option value="22">22</option>\n<option value="23">23</option>\n<option value="24">24</option>\n<option value="25">25</option>\n<option value="26">26</option>\n<option value="27">27</option>\n<option value="28">28</option>\n<option value="29">29</option>\n<option value="30">30</option>\n<option value="31">31</option>\n<option value="32">32</option>\n<option value="33">33</option>\n<option value="34">34</option>\n<option value="35">35</option>\n<option value="36">36</option>\n<option value="37">37</option>\n<option value="38">38</option>\n<option value="39">39</option>\n<option value="40">40</option>\n<option value="41">41</option>\n<option value="42">42</option>\n<option value="43">43</option>\n<option value="44">44</option>\n<option value="45">45</option>\n<option value="46">46</option>\n<option value="47">47</option>\n<option value="48">48</option>\n<option value="49">49</option>\n<option value="50">50</option>\n<option value="51">51</option>\n<option value="52">52</option>\n<option value="53">53</option>\n<option value="54">54</option>\n<option value="55">55</option>\n<option value="56">56</option>\n<option value="57">57</option>\n<option value="58">58</option>\n<option value="59">59</option>\n)
     expected << "</select>\n"
 
-    assert_dom_equal expected, select_datetime(Time.mktime(2003, 8, 16, 8, 4, 18), :start_year => 2003, :end_year => 2005,
-                                               :prefix => "date[first]", :prompt => true)
+    assert_dom_equal expected, select_datetime(Time.mktime(2003, 8, 16, 8, 4, 18), start_year: 2003, end_year: 2005,
+                                               prefix: "date[first]", prompt: true)
   end
 
   def test_select_datetime_with_custom_prompt
-
-    expected =  %(<select id="date_first_year" name="date[first][year]">\n)
+    expected =  %(<select id="date_first_year" name="date[first][year]">\n).dup
     expected << %(<option value="">Choose year</option>\n<option value="2003" selected="selected">2003</option>\n<option value="2004">2004</option>\n<option value="2005">2005</option>\n)
     expected << "</select>\n"
 
@@ -1426,12 +1451,12 @@ class DateHelperTest < ActionView::TestCase
     expected << %(<option value="">Choose minute</option>\n<option value="00">00</option>\n<option value="01">01</option>\n<option value="02">02</option>\n<option value="03">03</option>\n<option value="04" selected="selected">04</option>\n<option value="05">05</option>\n<option value="06">06</option>\n<option value="07">07</option>\n<option value="08">08</option>\n<option value="09">09</option>\n<option value="10">10</option>\n<option value="11">11</option>\n<option value="12">12</option>\n<option value="13">13</option>\n<option value="14">14</option>\n<option value="15">15</option>\n<option value="16">16</option>\n<option value="17">17</option>\n<option value="18">18</option>\n<option value="19">19</option>\n<option value="20">20</option>\n<option value="21">21</option>\n<option value="22">22</option>\n<option value="23">23</option>\n<option value="24">24</option>\n<option value="25">25</option>\n<option value="26">26</option>\n<option value="27">27</option>\n<option value="28">28</option>\n<option value="29">29</option>\n<option value="30">30</option>\n<option value="31">31</option>\n<option value="32">32</option>\n<option value="33">33</option>\n<option value="34">34</option>\n<option value="35">35</option>\n<option value="36">36</option>\n<option value="37">37</option>\n<option value="38">38</option>\n<option value="39">39</option>\n<option value="40">40</option>\n<option value="41">41</option>\n<option value="42">42</option>\n<option value="43">43</option>\n<option value="44">44</option>\n<option value="45">45</option>\n<option value="46">46</option>\n<option value="47">47</option>\n<option value="48">48</option>\n<option value="49">49</option>\n<option value="50">50</option>\n<option value="51">51</option>\n<option value="52">52</option>\n<option value="53">53</option>\n<option value="54">54</option>\n<option value="55">55</option>\n<option value="56">56</option>\n<option value="57">57</option>\n<option value="58">58</option>\n<option value="59">59</option>\n)
     expected << "</select>\n"
 
-    assert_dom_equal expected, select_datetime(Time.mktime(2003, 8, 16, 8, 4, 18), :start_year => 2003, :end_year => 2005, :prefix => "date[first]",
-      :prompt => {:day => 'Choose day', :month => 'Choose month', :year => 'Choose year', :hour => 'Choose hour', :minute => 'Choose minute'})
+    assert_dom_equal expected, select_datetime(Time.mktime(2003, 8, 16, 8, 4, 18), start_year: 2003, end_year: 2005, prefix: "date[first]",
+      prompt: { day: "Choose day", month: "Choose month", year: "Choose year", hour: "Choose hour", minute: "Choose minute" })
   end
 
   def test_select_datetime_with_generic_with_css_classes
-    expected =  %(<select id="date_year" name="date[year]" class="year">\n)
+    expected =  %(<select id="date_year" name="date[year]" class="year">\n).dup
     expected << %(<option value="2003" selected="selected">2003</option>\n<option value="2004">2004</option>\n<option value="2005">2005</option>\n)
     expected << "</select>\n"
 
@@ -1459,7 +1484,7 @@ class DateHelperTest < ActionView::TestCase
   end
 
   def test_select_datetime_with_custom_with_css_classes
-    expected =  %(<select id="date_year" name="date[year]" class="my-year">\n)
+    expected =  %(<select id="date_year" name="date[year]" class="my-year">\n).dup
     expected << %(<option value="2003" selected="selected">2003</option>\n<option value="2004">2004</option>\n<option value="2005">2005</option>\n)
     expected << "</select>\n"
 
@@ -1483,11 +1508,11 @@ class DateHelperTest < ActionView::TestCase
     expected << %(<option value="00">00</option>\n<option value="01">01</option>\n<option value="02">02</option>\n<option value="03">03</option>\n<option value="04" selected="selected">04</option>\n<option value="05">05</option>\n<option value="06">06</option>\n<option value="07">07</option>\n<option value="08">08</option>\n<option value="09">09</option>\n<option value="10">10</option>\n<option value="11">11</option>\n<option value="12">12</option>\n<option value="13">13</option>\n<option value="14">14</option>\n<option value="15">15</option>\n<option value="16">16</option>\n<option value="17">17</option>\n<option value="18">18</option>\n<option value="19">19</option>\n<option value="20">20</option>\n<option value="21">21</option>\n<option value="22">22</option>\n<option value="23">23</option>\n<option value="24">24</option>\n<option value="25">25</option>\n<option value="26">26</option>\n<option value="27">27</option>\n<option value="28">28</option>\n<option value="29">29</option>\n<option value="30">30</option>\n<option value="31">31</option>\n<option value="32">32</option>\n<option value="33">33</option>\n<option value="34">34</option>\n<option value="35">35</option>\n<option value="36">36</option>\n<option value="37">37</option>\n<option value="38">38</option>\n<option value="39">39</option>\n<option value="40">40</option>\n<option value="41">41</option>\n<option value="42">42</option>\n<option value="43">43</option>\n<option value="44">44</option>\n<option value="45">45</option>\n<option value="46">46</option>\n<option value="47">47</option>\n<option value="48">48</option>\n<option value="49">49</option>\n<option value="50">50</option>\n<option value="51">51</option>\n<option value="52">52</option>\n<option value="53">53</option>\n<option value="54">54</option>\n<option value="55">55</option>\n<option value="56">56</option>\n<option value="57">57</option>\n<option value="58">58</option>\n<option value="59">59</option>\n)
     expected << "</select>\n"
 
-    assert_dom_equal expected, select_datetime(Time.mktime(2003, 8, 16, 8, 4, 18), start_year: 2003, end_year: 2005, with_css_classes: { day: 'my-day', month: 'my-month', year: 'my-year', hour: 'my-hour', minute: 'my-minute' })
+    assert_dom_equal expected, select_datetime(Time.mktime(2003, 8, 16, 8, 4, 18), start_year: 2003, end_year: 2005, with_css_classes: { day: "my-day", month: "my-month", year: "my-year", hour: "my-hour", minute: "my-minute" })
   end
 
   def test_select_datetime_with_custom_hours
-    expected =  %(<select id="date_first_year" name="date[first][year]">\n)
+    expected =  %(<select id="date_first_year" name="date[first][year]">\n).dup
     expected << %(<option value="">Choose year</option>\n<option value="2003" selected="selected">2003</option>\n<option value="2004">2004</option>\n<option value="2005">2005</option>\n)
     expected << "</select>\n"
 
@@ -1511,24 +1536,24 @@ class DateHelperTest < ActionView::TestCase
     expected << %(<option value="">Choose minute</option>\n<option value="00">00</option>\n<option value="01">01</option>\n<option value="02">02</option>\n<option value="03">03</option>\n<option value="04" selected="selected">04</option>\n<option value="05">05</option>\n<option value="06">06</option>\n<option value="07">07</option>\n<option value="08">08</option>\n<option value="09">09</option>\n<option value="10">10</option>\n<option value="11">11</option>\n<option value="12">12</option>\n<option value="13">13</option>\n<option value="14">14</option>\n<option value="15">15</option>\n<option value="16">16</option>\n<option value="17">17</option>\n<option value="18">18</option>\n<option value="19">19</option>\n<option value="20">20</option>\n<option value="21">21</option>\n<option value="22">22</option>\n<option value="23">23</option>\n<option value="24">24</option>\n<option value="25">25</option>\n<option value="26">26</option>\n<option value="27">27</option>\n<option value="28">28</option>\n<option value="29">29</option>\n<option value="30">30</option>\n<option value="31">31</option>\n<option value="32">32</option>\n<option value="33">33</option>\n<option value="34">34</option>\n<option value="35">35</option>\n<option value="36">36</option>\n<option value="37">37</option>\n<option value="38">38</option>\n<option value="39">39</option>\n<option value="40">40</option>\n<option value="41">41</option>\n<option value="42">42</option>\n<option value="43">43</option>\n<option value="44">44</option>\n<option value="45">45</option>\n<option value="46">46</option>\n<option value="47">47</option>\n<option value="48">48</option>\n<option value="49">49</option>\n<option value="50">50</option>\n<option value="51">51</option>\n<option value="52">52</option>\n<option value="53">53</option>\n<option value="54">54</option>\n<option value="55">55</option>\n<option value="56">56</option>\n<option value="57">57</option>\n<option value="58">58</option>\n<option value="59">59</option>\n)
     expected << "</select>\n"
 
-    assert_dom_equal expected, select_datetime(Time.mktime(2003, 8, 16, 8, 4, 18), :start_year => 2003, :end_year => 2005, :start_hour => 1, :end_hour => 9, :prefix => "date[first]",
-      :prompt => {:day => 'Choose day', :month => 'Choose month', :year => 'Choose year', :hour => 'Choose hour', :minute => 'Choose minute'})
+    assert_dom_equal expected, select_datetime(Time.mktime(2003, 8, 16, 8, 4, 18), start_year: 2003, end_year: 2005, start_hour: 1, end_hour: 9, prefix: "date[first]",
+      prompt: { day: "Choose day", month: "Choose month", year: "Choose year", hour: "Choose hour", minute: "Choose minute" })
   end
 
   def test_select_datetime_with_hidden
-    expected =  %(<input id="date_first_year" name="date[first][year]" type="hidden" value="2003" />\n)
+    expected =  %(<input id="date_first_year" name="date[first][year]" type="hidden" value="2003" />\n).dup
     expected << %(<input id="date_first_month" name="date[first][month]" type="hidden" value="8" />\n)
     expected << %(<input id="date_first_day" name="date[first][day]" type="hidden" value="16" />\n)
     expected << %(<input id="date_first_hour" name="date[first][hour]" type="hidden" value="8" />\n)
     expected << %(<input id="date_first_minute" name="date[first][minute]" type="hidden" value="4" />\n)
 
-    assert_dom_equal expected, select_datetime(Time.mktime(2003, 8, 16, 8, 4, 18), :prefix => "date[first]", :use_hidden => true)
-    assert_dom_equal expected, select_datetime(Time.mktime(2003, 8, 16, 8, 4, 18), :datetime_separator => "&mdash;", :date_separator => "/",
-      :time_separator => ":", :prefix => "date[first]", :use_hidden => true)
+    assert_dom_equal expected, select_datetime(Time.mktime(2003, 8, 16, 8, 4, 18), prefix: "date[first]", use_hidden: true)
+    assert_dom_equal expected, select_datetime(Time.mktime(2003, 8, 16, 8, 4, 18), datetime_separator: "&mdash;", date_separator: "/",
+      time_separator: ":", prefix: "date[first]", use_hidden: true)
   end
 
   def test_select_time
-    expected = %(<input name="date[year]" id="date_year" value="2003" type="hidden" />\n)
+    expected = %(<input name="date[year]" id="date_year" value="2003" type="hidden" />\n).dup
     expected << %(<input name="date[month]" id="date_month" value="8" type="hidden" />\n)
     expected << %(<input name="date[day]" id="date_day" value="16" type="hidden" />\n)
 
@@ -1543,11 +1568,11 @@ class DateHelperTest < ActionView::TestCase
     expected << "</select>\n"
 
     assert_dom_equal expected, select_time(Time.mktime(2003, 8, 16, 8, 4, 18))
-    assert_dom_equal expected, select_time(Time.mktime(2003, 8, 16, 8, 4, 18), :include_seconds => false)
+    assert_dom_equal expected, select_time(Time.mktime(2003, 8, 16, 8, 4, 18), include_seconds: false)
   end
 
   def test_select_time_with_ampm
-    expected = %(<input name="date[year]" id="date_year" value="2003" type="hidden" />\n)
+    expected = %(<input name="date[year]" id="date_year" value="2003" type="hidden" />\n).dup
     expected << %(<input name="date[month]" id="date_month" value="8" type="hidden" />\n)
     expected << %(<input name="date[day]" id="date_day" value="16" type="hidden" />\n)
 
@@ -1561,11 +1586,11 @@ class DateHelperTest < ActionView::TestCase
     expected << %(<option value="00">00</option>\n<option value="01">01</option>\n<option value="02">02</option>\n<option value="03">03</option>\n<option value="04" selected="selected">04</option>\n<option value="05">05</option>\n<option value="06">06</option>\n<option value="07">07</option>\n<option value="08">08</option>\n<option value="09">09</option>\n<option value="10">10</option>\n<option value="11">11</option>\n<option value="12">12</option>\n<option value="13">13</option>\n<option value="14">14</option>\n<option value="15">15</option>\n<option value="16">16</option>\n<option value="17">17</option>\n<option value="18">18</option>\n<option value="19">19</option>\n<option value="20">20</option>\n<option value="21">21</option>\n<option value="22">22</option>\n<option value="23">23</option>\n<option value="24">24</option>\n<option value="25">25</option>\n<option value="26">26</option>\n<option value="27">27</option>\n<option value="28">28</option>\n<option value="29">29</option>\n<option value="30">30</option>\n<option value="31">31</option>\n<option value="32">32</option>\n<option value="33">33</option>\n<option value="34">34</option>\n<option value="35">35</option>\n<option value="36">36</option>\n<option value="37">37</option>\n<option value="38">38</option>\n<option value="39">39</option>\n<option value="40">40</option>\n<option value="41">41</option>\n<option value="42">42</option>\n<option value="43">43</option>\n<option value="44">44</option>\n<option value="45">45</option>\n<option value="46">46</option>\n<option value="47">47</option>\n<option value="48">48</option>\n<option value="49">49</option>\n<option value="50">50</option>\n<option value="51">51</option>\n<option value="52">52</option>\n<option value="53">53</option>\n<option value="54">54</option>\n<option value="55">55</option>\n<option value="56">56</option>\n<option value="57">57</option>\n<option value="58">58</option>\n<option value="59">59</option>\n)
     expected << "</select>\n"
 
-    assert_dom_equal expected, select_time(Time.mktime(2003, 8, 16, 8, 4, 18), :include_seconds => false, :ampm => true)
+    assert_dom_equal expected, select_time(Time.mktime(2003, 8, 16, 8, 4, 18), include_seconds: false, ampm: true)
   end
 
   def test_select_time_with_separator
-    expected = %(<input name="date[year]" id="date_year" value="2003" type="hidden" />\n)
+    expected = %(<input name="date[year]" id="date_year" value="2003" type="hidden" />\n).dup
     expected << %(<input name="date[month]" id="date_month" value="8" type="hidden" />\n)
     expected << %(<input name="date[day]" id="date_day" value="16" type="hidden" />\n)
     expected << %(<select id="date_hour" name="date[hour]">\n)
@@ -1578,12 +1603,12 @@ class DateHelperTest < ActionView::TestCase
     expected << %(<option value="00">00</option>\n<option value="01">01</option>\n<option value="02">02</option>\n<option value="03">03</option>\n<option value="04" selected="selected">04</option>\n<option value="05">05</option>\n<option value="06">06</option>\n<option value="07">07</option>\n<option value="08">08</option>\n<option value="09">09</option>\n<option value="10">10</option>\n<option value="11">11</option>\n<option value="12">12</option>\n<option value="13">13</option>\n<option value="14">14</option>\n<option value="15">15</option>\n<option value="16">16</option>\n<option value="17">17</option>\n<option value="18">18</option>\n<option value="19">19</option>\n<option value="20">20</option>\n<option value="21">21</option>\n<option value="22">22</option>\n<option value="23">23</option>\n<option value="24">24</option>\n<option value="25">25</option>\n<option value="26">26</option>\n<option value="27">27</option>\n<option value="28">28</option>\n<option value="29">29</option>\n<option value="30">30</option>\n<option value="31">31</option>\n<option value="32">32</option>\n<option value="33">33</option>\n<option value="34">34</option>\n<option value="35">35</option>\n<option value="36">36</option>\n<option value="37">37</option>\n<option value="38">38</option>\n<option value="39">39</option>\n<option value="40">40</option>\n<option value="41">41</option>\n<option value="42">42</option>\n<option value="43">43</option>\n<option value="44">44</option>\n<option value="45">45</option>\n<option value="46">46</option>\n<option value="47">47</option>\n<option value="48">48</option>\n<option value="49">49</option>\n<option value="50">50</option>\n<option value="51">51</option>\n<option value="52">52</option>\n<option value="53">53</option>\n<option value="54">54</option>\n<option value="55">55</option>\n<option value="56">56</option>\n<option value="57">57</option>\n<option value="58">58</option>\n<option value="59">59</option>\n)
     expected << "</select>\n"
 
-    assert_dom_equal expected, select_time(Time.mktime(2003, 8, 16, 8, 4, 18), :time_separator => ' : ')
-    assert_dom_equal expected, select_time(Time.mktime(2003, 8, 16, 8, 4, 18), :time_separator => ' : ', :include_seconds => false)
+    assert_dom_equal expected, select_time(Time.mktime(2003, 8, 16, 8, 4, 18), time_separator: " : ")
+    assert_dom_equal expected, select_time(Time.mktime(2003, 8, 16, 8, 4, 18), time_separator: " : ", include_seconds: false)
   end
 
   def test_select_time_with_seconds
-    expected = %(<input name="date[year]" id="date_year" value="2003" type="hidden" />\n)
+    expected = %(<input name="date[year]" id="date_year" value="2003" type="hidden" />\n).dup
     expected << %(<input name="date[month]" id="date_month" value="8" type="hidden" />\n)
     expected << %(<input name="date[day]" id="date_day" value="16" type="hidden" />\n)
 
@@ -1591,23 +1616,23 @@ class DateHelperTest < ActionView::TestCase
     expected << %(<option value="00">00</option>\n<option value="01">01</option>\n<option value="02">02</option>\n<option value="03">03</option>\n<option value="04">04</option>\n<option value="05">05</option>\n<option value="06">06</option>\n<option value="07">07</option>\n<option value="08" selected="selected">08</option>\n<option value="09">09</option>\n<option value="10">10</option>\n<option value="11">11</option>\n<option value="12">12</option>\n<option value="13">13</option>\n<option value="14">14</option>\n<option value="15">15</option>\n<option value="16">16</option>\n<option value="17">17</option>\n<option value="18">18</option>\n<option value="19">19</option>\n<option value="20">20</option>\n<option value="21">21</option>\n<option value="22">22</option>\n<option value="23">23</option>\n)
     expected << "</select>\n"
 
-    expected << ' : '
+    expected << " : "
 
     expected << %(<select id="date_minute" name="date[minute]">\n)
     expected << %(<option value="00">00</option>\n<option value="01">01</option>\n<option value="02">02</option>\n<option value="03">03</option>\n<option value="04" selected="selected">04</option>\n<option value="05">05</option>\n<option value="06">06</option>\n<option value="07">07</option>\n<option value="08">08</option>\n<option value="09">09</option>\n<option value="10">10</option>\n<option value="11">11</option>\n<option value="12">12</option>\n<option value="13">13</option>\n<option value="14">14</option>\n<option value="15">15</option>\n<option value="16">16</option>\n<option value="17">17</option>\n<option value="18">18</option>\n<option value="19">19</option>\n<option value="20">20</option>\n<option value="21">21</option>\n<option value="22">22</option>\n<option value="23">23</option>\n<option value="24">24</option>\n<option value="25">25</option>\n<option value="26">26</option>\n<option value="27">27</option>\n<option value="28">28</option>\n<option value="29">29</option>\n<option value="30">30</option>\n<option value="31">31</option>\n<option value="32">32</option>\n<option value="33">33</option>\n<option value="34">34</option>\n<option value="35">35</option>\n<option value="36">36</option>\n<option value="37">37</option>\n<option value="38">38</option>\n<option value="39">39</option>\n<option value="40">40</option>\n<option value="41">41</option>\n<option value="42">42</option>\n<option value="43">43</option>\n<option value="44">44</option>\n<option value="45">45</option>\n<option value="46">46</option>\n<option value="47">47</option>\n<option value="48">48</option>\n<option value="49">49</option>\n<option value="50">50</option>\n<option value="51">51</option>\n<option value="52">52</option>\n<option value="53">53</option>\n<option value="54">54</option>\n<option value="55">55</option>\n<option value="56">56</option>\n<option value="57">57</option>\n<option value="58">58</option>\n<option value="59">59</option>\n)
     expected << "</select>\n"
 
-    expected << ' : '
+    expected << " : "
 
     expected << %(<select id="date_second" name="date[second]">\n)
     expected << %(<option value="00">00</option>\n<option value="01">01</option>\n<option value="02">02</option>\n<option value="03">03</option>\n<option value="04">04</option>\n<option value="05">05</option>\n<option value="06">06</option>\n<option value="07">07</option>\n<option value="08">08</option>\n<option value="09">09</option>\n<option value="10">10</option>\n<option value="11">11</option>\n<option value="12">12</option>\n<option value="13">13</option>\n<option value="14">14</option>\n<option value="15">15</option>\n<option value="16">16</option>\n<option value="17">17</option>\n<option value="18" selected="selected">18</option>\n<option value="19">19</option>\n<option value="20">20</option>\n<option value="21">21</option>\n<option value="22">22</option>\n<option value="23">23</option>\n<option value="24">24</option>\n<option value="25">25</option>\n<option value="26">26</option>\n<option value="27">27</option>\n<option value="28">28</option>\n<option value="29">29</option>\n<option value="30">30</option>\n<option value="31">31</option>\n<option value="32">32</option>\n<option value="33">33</option>\n<option value="34">34</option>\n<option value="35">35</option>\n<option value="36">36</option>\n<option value="37">37</option>\n<option value="38">38</option>\n<option value="39">39</option>\n<option value="40">40</option>\n<option value="41">41</option>\n<option value="42">42</option>\n<option value="43">43</option>\n<option value="44">44</option>\n<option value="45">45</option>\n<option value="46">46</option>\n<option value="47">47</option>\n<option value="48">48</option>\n<option value="49">49</option>\n<option value="50">50</option>\n<option value="51">51</option>\n<option value="52">52</option>\n<option value="53">53</option>\n<option value="54">54</option>\n<option value="55">55</option>\n<option value="56">56</option>\n<option value="57">57</option>\n<option value="58">58</option>\n<option value="59">59</option>\n)
     expected << "</select>\n"
 
-    assert_dom_equal expected, select_time(Time.mktime(2003, 8, 16, 8, 4, 18), :include_seconds => true)
+    assert_dom_equal expected, select_time(Time.mktime(2003, 8, 16, 8, 4, 18), include_seconds: true)
   end
 
   def test_select_time_with_seconds_and_separator
-    expected = %(<input name="date[year]" id="date_year" value="2003" type="hidden" />\n)
+    expected = %(<input name="date[year]" id="date_year" value="2003" type="hidden" />\n).dup
     expected << %(<input name="date[month]" id="date_month" value="8" type="hidden" />\n)
     expected << %(<input name="date[day]" id="date_day" value="16" type="hidden" />\n)
 
@@ -1627,11 +1652,11 @@ class DateHelperTest < ActionView::TestCase
     expected << %(<option value="00">00</option>\n<option value="01">01</option>\n<option value="02">02</option>\n<option value="03">03</option>\n<option value="04">04</option>\n<option value="05">05</option>\n<option value="06">06</option>\n<option value="07">07</option>\n<option value="08">08</option>\n<option value="09">09</option>\n<option value="10">10</option>\n<option value="11">11</option>\n<option value="12">12</option>\n<option value="13">13</option>\n<option value="14">14</option>\n<option value="15">15</option>\n<option value="16">16</option>\n<option value="17">17</option>\n<option value="18" selected="selected">18</option>\n<option value="19">19</option>\n<option value="20">20</option>\n<option value="21">21</option>\n<option value="22">22</option>\n<option value="23">23</option>\n<option value="24">24</option>\n<option value="25">25</option>\n<option value="26">26</option>\n<option value="27">27</option>\n<option value="28">28</option>\n<option value="29">29</option>\n<option value="30">30</option>\n<option value="31">31</option>\n<option value="32">32</option>\n<option value="33">33</option>\n<option value="34">34</option>\n<option value="35">35</option>\n<option value="36">36</option>\n<option value="37">37</option>\n<option value="38">38</option>\n<option value="39">39</option>\n<option value="40">40</option>\n<option value="41">41</option>\n<option value="42">42</option>\n<option value="43">43</option>\n<option value="44">44</option>\n<option value="45">45</option>\n<option value="46">46</option>\n<option value="47">47</option>\n<option value="48">48</option>\n<option value="49">49</option>\n<option value="50">50</option>\n<option value="51">51</option>\n<option value="52">52</option>\n<option value="53">53</option>\n<option value="54">54</option>\n<option value="55">55</option>\n<option value="56">56</option>\n<option value="57">57</option>\n<option value="58">58</option>\n<option value="59">59</option>\n)
     expected << "</select>\n"
 
-    assert_dom_equal expected, select_time(Time.mktime(2003, 8, 16, 8, 4, 18), :include_seconds => true, :time_separator => ' : ')
+    assert_dom_equal expected, select_time(Time.mktime(2003, 8, 16, 8, 4, 18), include_seconds: true, time_separator: " : ")
   end
 
   def test_select_time_with_html_options
-    expected = %(<input name="date[year]" id="date_year" value="2003" type="hidden" />\n)
+    expected = %(<input name="date[year]" id="date_year" value="2003" type="hidden" />\n).dup
     expected << %(<input name="date[month]" id="date_month" value="8" type="hidden" />\n)
     expected << %(<input name="date[day]" id="date_day" value="16" type="hidden" />\n)
 
@@ -1645,8 +1670,8 @@ class DateHelperTest < ActionView::TestCase
     expected << %(<option value="00">00</option>\n<option value="01">01</option>\n<option value="02">02</option>\n<option value="03">03</option>\n<option value="04" selected="selected">04</option>\n<option value="05">05</option>\n<option value="06">06</option>\n<option value="07">07</option>\n<option value="08">08</option>\n<option value="09">09</option>\n<option value="10">10</option>\n<option value="11">11</option>\n<option value="12">12</option>\n<option value="13">13</option>\n<option value="14">14</option>\n<option value="15">15</option>\n<option value="16">16</option>\n<option value="17">17</option>\n<option value="18">18</option>\n<option value="19">19</option>\n<option value="20">20</option>\n<option value="21">21</option>\n<option value="22">22</option>\n<option value="23">23</option>\n<option value="24">24</option>\n<option value="25">25</option>\n<option value="26">26</option>\n<option value="27">27</option>\n<option value="28">28</option>\n<option value="29">29</option>\n<option value="30">30</option>\n<option value="31">31</option>\n<option value="32">32</option>\n<option value="33">33</option>\n<option value="34">34</option>\n<option value="35">35</option>\n<option value="36">36</option>\n<option value="37">37</option>\n<option value="38">38</option>\n<option value="39">39</option>\n<option value="40">40</option>\n<option value="41">41</option>\n<option value="42">42</option>\n<option value="43">43</option>\n<option value="44">44</option>\n<option value="45">45</option>\n<option value="46">46</option>\n<option value="47">47</option>\n<option value="48">48</option>\n<option value="49">49</option>\n<option value="50">50</option>\n<option value="51">51</option>\n<option value="52">52</option>\n<option value="53">53</option>\n<option value="54">54</option>\n<option value="55">55</option>\n<option value="56">56</option>\n<option value="57">57</option>\n<option value="58">58</option>\n<option value="59">59</option>\n)
     expected << "</select>\n"
 
-    assert_dom_equal expected, select_time(Time.mktime(2003, 8, 16, 8, 4, 18), {}, :class => 'selector')
-    assert_dom_equal expected, select_time(Time.mktime(2003, 8, 16, 8, 4, 18), {:include_seconds => false}, :class => 'selector')
+    assert_dom_equal expected, select_time(Time.mktime(2003, 8, 16, 8, 4, 18), {}, { class: "selector" })
+    assert_dom_equal expected, select_time(Time.mktime(2003, 8, 16, 8, 4, 18), { include_seconds: false }, { class: "selector" })
   end
 
   def test_select_time_should_work_with_date
@@ -1654,7 +1679,7 @@ class DateHelperTest < ActionView::TestCase
   end
 
   def test_select_time_with_default_prompt
-    expected = %(<input name="date[year]" id="date_year" value="2003" type="hidden" />\n)
+    expected = %(<input name="date[year]" id="date_year" value="2003" type="hidden" />\n).dup
     expected << %(<input name="date[month]" id="date_month" value="8" type="hidden" />\n)
     expected << %(<input name="date[day]" id="date_day" value="16" type="hidden" />\n)
 
@@ -1674,11 +1699,11 @@ class DateHelperTest < ActionView::TestCase
     expected << %(<option value="">Seconds</option>\n<option value="00">00</option>\n<option value="01">01</option>\n<option value="02">02</option>\n<option value="03">03</option>\n<option value="04">04</option>\n<option value="05">05</option>\n<option value="06">06</option>\n<option value="07">07</option>\n<option value="08">08</option>\n<option value="09">09</option>\n<option value="10">10</option>\n<option value="11">11</option>\n<option value="12">12</option>\n<option value="13">13</option>\n<option value="14">14</option>\n<option value="15">15</option>\n<option value="16">16</option>\n<option value="17">17</option>\n<option value="18" selected="selected">18</option>\n<option value="19">19</option>\n<option value="20">20</option>\n<option value="21">21</option>\n<option value="22">22</option>\n<option value="23">23</option>\n<option value="24">24</option>\n<option value="25">25</option>\n<option value="26">26</option>\n<option value="27">27</option>\n<option value="28">28</option>\n<option value="29">29</option>\n<option value="30">30</option>\n<option value="31">31</option>\n<option value="32">32</option>\n<option value="33">33</option>\n<option value="34">34</option>\n<option value="35">35</option>\n<option value="36">36</option>\n<option value="37">37</option>\n<option value="38">38</option>\n<option value="39">39</option>\n<option value="40">40</option>\n<option value="41">41</option>\n<option value="42">42</option>\n<option value="43">43</option>\n<option value="44">44</option>\n<option value="45">45</option>\n<option value="46">46</option>\n<option value="47">47</option>\n<option value="48">48</option>\n<option value="49">49</option>\n<option value="50">50</option>\n<option value="51">51</option>\n<option value="52">52</option>\n<option value="53">53</option>\n<option value="54">54</option>\n<option value="55">55</option>\n<option value="56">56</option>\n<option value="57">57</option>\n<option value="58">58</option>\n<option value="59">59</option>\n)
     expected << "</select>\n"
 
-    assert_dom_equal expected, select_time(Time.mktime(2003, 8, 16, 8, 4, 18), :include_seconds => true, :prompt => true)
+    assert_dom_equal expected, select_time(Time.mktime(2003, 8, 16, 8, 4, 18), include_seconds: true, prompt: true)
   end
 
   def test_select_time_with_custom_prompt
-    expected = %(<input name="date[year]" id="date_year" value="2003" type="hidden" />\n)
+    expected = %(<input name="date[year]" id="date_year" value="2003" type="hidden" />\n).dup
     expected << %(<input name="date[month]" id="date_month" value="8" type="hidden" />\n)
     expected << %(<input name="date[day]" id="date_day" value="16" type="hidden" />\n)
 
@@ -1698,12 +1723,12 @@ class DateHelperTest < ActionView::TestCase
     expected << %(<option value="">Choose seconds</option>\n<option value="00">00</option>\n<option value="01">01</option>\n<option value="02">02</option>\n<option value="03">03</option>\n<option value="04">04</option>\n<option value="05">05</option>\n<option value="06">06</option>\n<option value="07">07</option>\n<option value="08">08</option>\n<option value="09">09</option>\n<option value="10">10</option>\n<option value="11">11</option>\n<option value="12">12</option>\n<option value="13">13</option>\n<option value="14">14</option>\n<option value="15">15</option>\n<option value="16">16</option>\n<option value="17">17</option>\n<option value="18" selected="selected">18</option>\n<option value="19">19</option>\n<option value="20">20</option>\n<option value="21">21</option>\n<option value="22">22</option>\n<option value="23">23</option>\n<option value="24">24</option>\n<option value="25">25</option>\n<option value="26">26</option>\n<option value="27">27</option>\n<option value="28">28</option>\n<option value="29">29</option>\n<option value="30">30</option>\n<option value="31">31</option>\n<option value="32">32</option>\n<option value="33">33</option>\n<option value="34">34</option>\n<option value="35">35</option>\n<option value="36">36</option>\n<option value="37">37</option>\n<option value="38">38</option>\n<option value="39">39</option>\n<option value="40">40</option>\n<option value="41">41</option>\n<option value="42">42</option>\n<option value="43">43</option>\n<option value="44">44</option>\n<option value="45">45</option>\n<option value="46">46</option>\n<option value="47">47</option>\n<option value="48">48</option>\n<option value="49">49</option>\n<option value="50">50</option>\n<option value="51">51</option>\n<option value="52">52</option>\n<option value="53">53</option>\n<option value="54">54</option>\n<option value="55">55</option>\n<option value="56">56</option>\n<option value="57">57</option>\n<option value="58">58</option>\n<option value="59">59</option>\n)
     expected << "</select>\n"
 
-    assert_dom_equal expected, select_time(Time.mktime(2003, 8, 16, 8, 4, 18), :include_seconds => true,
-      :prompt => {:hour => 'Choose hour', :minute => 'Choose minute', :second => 'Choose seconds'})
+    assert_dom_equal expected, select_time(Time.mktime(2003, 8, 16, 8, 4, 18), include_seconds: true,
+      prompt: { hour: "Choose hour", minute: "Choose minute", second: "Choose seconds" })
   end
 
   def test_select_time_with_generic_with_css_classes
-    expected  = %(<input name="date[year]" id="date_year" value="2003" type="hidden" />\n)
+    expected = %(<input name="date[year]" id="date_year" value="2003" type="hidden" />\n).dup
     expected << %(<input name="date[month]" id="date_month" value="8" type="hidden" />\n)
     expected << %(<input name="date[day]" id="date_day" value="16" type="hidden" />\n)
 
@@ -1727,7 +1752,7 @@ class DateHelperTest < ActionView::TestCase
   end
 
   def test_select_time_with_custom_with_css_classes
-    expected  = %(<input name="date[year]" id="date_year" value="2003" type="hidden" />\n)
+    expected = %(<input name="date[year]" id="date_year" value="2003" type="hidden" />\n).dup
     expected << %(<input name="date[month]" id="date_month" value="8" type="hidden" />\n)
     expected << %(<input name="date[day]" id="date_day" value="16" type="hidden" />\n)
 
@@ -1747,25 +1772,25 @@ class DateHelperTest < ActionView::TestCase
     expected << %(<option value="00">00</option>\n<option value="01">01</option>\n<option value="02">02</option>\n<option value="03">03</option>\n<option value="04">04</option>\n<option value="05">05</option>\n<option value="06">06</option>\n<option value="07">07</option>\n<option value="08">08</option>\n<option value="09">09</option>\n<option value="10">10</option>\n<option value="11">11</option>\n<option value="12">12</option>\n<option value="13">13</option>\n<option value="14">14</option>\n<option value="15">15</option>\n<option value="16">16</option>\n<option value="17">17</option>\n<option value="18" selected="selected">18</option>\n<option value="19">19</option>\n<option value="20">20</option>\n<option value="21">21</option>\n<option value="22">22</option>\n<option value="23">23</option>\n<option value="24">24</option>\n<option value="25">25</option>\n<option value="26">26</option>\n<option value="27">27</option>\n<option value="28">28</option>\n<option value="29">29</option>\n<option value="30">30</option>\n<option value="31">31</option>\n<option value="32">32</option>\n<option value="33">33</option>\n<option value="34">34</option>\n<option value="35">35</option>\n<option value="36">36</option>\n<option value="37">37</option>\n<option value="38">38</option>\n<option value="39">39</option>\n<option value="40">40</option>\n<option value="41">41</option>\n<option value="42">42</option>\n<option value="43">43</option>\n<option value="44">44</option>\n<option value="45">45</option>\n<option value="46">46</option>\n<option value="47">47</option>\n<option value="48">48</option>\n<option value="49">49</option>\n<option value="50">50</option>\n<option value="51">51</option>\n<option value="52">52</option>\n<option value="53">53</option>\n<option value="54">54</option>\n<option value="55">55</option>\n<option value="56">56</option>\n<option value="57">57</option>\n<option value="58">58</option>\n<option value="59">59</option>\n)
     expected << "</select>\n"
 
-    assert_dom_equal expected, select_time(Time.mktime(2003, 8, 16, 8, 4, 18), include_seconds: true, with_css_classes: { hour: 'my-hour', minute: 'my-minute', second: 'my-second' })
+    assert_dom_equal expected, select_time(Time.mktime(2003, 8, 16, 8, 4, 18), include_seconds: true, with_css_classes: { hour: "my-hour", minute: "my-minute", second: "my-second" })
   end
 
   def test_select_time_with_hidden
-    expected =  %(<input id="date_first_year" name="date[first][year]" type="hidden" value="2003" />\n)
+    expected =  %(<input id="date_first_year" name="date[first][year]" type="hidden" value="2003" />\n).dup
     expected << %(<input id="date_first_month" name="date[first][month]" type="hidden" value="8" />\n)
     expected << %(<input id="date_first_day" name="date[first][day]" type="hidden" value="16" />\n)
     expected << %(<input id="date_first_hour" name="date[first][hour]" type="hidden" value="8" />\n)
     expected << %(<input id="date_first_minute" name="date[first][minute]" type="hidden" value="4" />\n)
 
-    assert_dom_equal expected, select_time(Time.mktime(2003, 8, 16, 8, 4, 18), :prefix => "date[first]", :use_hidden => true)
-    assert_dom_equal expected, select_time(Time.mktime(2003, 8, 16, 8, 4, 18), :time_separator => ":", :prefix => "date[first]", :use_hidden => true)
+    assert_dom_equal expected, select_time(Time.mktime(2003, 8, 16, 8, 4, 18), prefix: "date[first]", use_hidden: true)
+    assert_dom_equal expected, select_time(Time.mktime(2003, 8, 16, 8, 4, 18), time_separator: ":", prefix: "date[first]", use_hidden: true)
   end
 
   def test_date_select
     @post = Post.new
     @post.written_on = Date.new(2004, 6, 15)
 
-    expected = %{<select id="post_written_on_1i" name="post[written_on(1i)]">\n}
+    expected = %{<select id="post_written_on_1i" name="post[written_on(1i)]">\n}.dup
     expected << %{<option value="1999">1999</option>\n<option value="2000">2000</option>\n<option value="2001">2001</option>\n<option value="2002">2002</option>\n<option value="2003">2003</option>\n<option value="2004" selected="selected">2004</option>\n<option value="2005">2005</option>\n<option value="2006">2006</option>\n<option value="2007">2007</option>\n<option value="2008">2008</option>\n<option value="2009">2009</option>\n}
     expected << "</select>\n"
 
@@ -1785,7 +1810,7 @@ class DateHelperTest < ActionView::TestCase
     @post = Post.new
     @post.written_on = Date.new(2004, 6, 15)
 
-    expected = %{<select id="post_written_on_1i" name="post[written_on(1i)]">\n}
+    expected = %{<select id="post_written_on_1i" name="post[written_on(1i)]">\n}.dup
     expected << %{<option value="1999">1999</option>\n<option value="2000">2000</option>\n<option value="2001">2001</option>\n<option value="2002">2002</option>\n<option value="2003">2003</option>\n<option selected="selected" value="2004">2004</option>\n<option value="2005">2005</option>\n<option value="2006">2006</option>\n<option value="2007">2007</option>\n<option value="2008">2008</option>\n<option value="2009">2009</option>\n}
     expected << "</select>\n"
 
@@ -1798,14 +1823,14 @@ class DateHelperTest < ActionView::TestCase
 
     expected << "</select>\n"
 
-    assert_dom_equal expected, date_select("post", "written_on", :selected => Date.new(2004, 07, 10))
+    assert_dom_equal expected, date_select("post", "written_on", selected: Date.new(2004, 07, 10))
   end
 
   def test_date_select_with_selected_in_hash
     @post = Post.new
     @post.written_on = Date.new(2004, 6, 15)
 
-    expected = %{<select id="post_written_on_1i" name="post[written_on(1i)]">\n}
+    expected = %{<select id="post_written_on_1i" name="post[written_on(1i)]">\n}.dup
     expected << %{<option value="1999">1999</option>\n<option value="2000">2000</option>\n<option value="2001">2001</option>\n<option value="2002">2002</option>\n<option value="2003">2003</option>\n<option selected="selected" value="2004">2004</option>\n<option value="2005">2005</option>\n<option value="2006">2006</option>\n<option value="2007">2007</option>\n<option value="2008">2008</option>\n<option value="2009">2009</option>\n}
     expected << "</select>\n"
 
@@ -1818,7 +1843,7 @@ class DateHelperTest < ActionView::TestCase
 
     expected << "</select>\n"
 
-    assert_dom_equal expected, date_select("post", "written_on", :selected => {day: 10, month: 07, year: 2004})
+    assert_dom_equal expected, date_select("post", "written_on", selected: { day: 10, month: 07, year: 2004 })
   end
 
   def test_date_select_with_selected_nil
@@ -1843,9 +1868,9 @@ class DateHelperTest < ActionView::TestCase
     @post = Post.new
     @post.written_on = Date.new(2004, 6, 15)
 
-    expected = "<input type=\"hidden\" id=\"post_written_on_3i\" name=\"post[written_on(3i)]\" value=\"1\" />\n"
+    expected = "<input type=\"hidden\" id=\"post_written_on_3i\" name=\"post[written_on(3i)]\" value=\"1\" />\n".dup
 
-    expected <<  %{<select id="post_written_on_2i" name="post[written_on(2i)]">\n}
+    expected << %{<select id="post_written_on_2i" name="post[written_on(2i)]">\n}
     expected << %{<option value="1">January</option>\n<option value="2">February</option>\n<option value="3">March</option>\n<option value="4">April</option>\n<option value="5">May</option>\n<option value="6" selected="selected">June</option>\n<option value="7">July</option>\n<option value="8">August</option>\n<option value="9">September</option>\n<option value="10">October</option>\n<option value="11">November</option>\n<option value="12">December</option>\n}
     expected << "</select>\n"
 
@@ -1853,30 +1878,30 @@ class DateHelperTest < ActionView::TestCase
     expected << %{<option value="1999">1999</option>\n<option value="2000">2000</option>\n<option value="2001">2001</option>\n<option value="2002">2002</option>\n<option value="2003">2003</option>\n<option value="2004" selected="selected">2004</option>\n<option value="2005">2005</option>\n<option value="2006">2006</option>\n<option value="2007">2007</option>\n<option value="2008">2008</option>\n<option value="2009">2009</option>\n}
     expected << "</select>\n"
 
-    assert_dom_equal expected, date_select("post", "written_on", :order => [ :month, :year ])
+    assert_dom_equal expected, date_select("post", "written_on", order: [ :month, :year ])
   end
 
   def test_date_select_without_day_and_month
     @post = Post.new
     @post.written_on = Date.new(2004, 2, 29)
 
-    expected = "<input type=\"hidden\" id=\"post_written_on_2i\" name=\"post[written_on(2i)]\" value=\"2\" />\n"
+    expected = "<input type=\"hidden\" id=\"post_written_on_2i\" name=\"post[written_on(2i)]\" value=\"2\" />\n".dup
     expected << "<input type=\"hidden\" id=\"post_written_on_3i\" name=\"post[written_on(3i)]\" value=\"1\" />\n"
 
     expected << %{<select id="post_written_on_1i" name="post[written_on(1i)]">\n}
     expected << %{<option value="1999">1999</option>\n<option value="2000">2000</option>\n<option value="2001">2001</option>\n<option value="2002">2002</option>\n<option value="2003">2003</option>\n<option value="2004" selected="selected">2004</option>\n<option value="2005">2005</option>\n<option value="2006">2006</option>\n<option value="2007">2007</option>\n<option value="2008">2008</option>\n<option value="2009">2009</option>\n}
     expected << "</select>\n"
 
-    assert_dom_equal expected, date_select("post", "written_on", :order => [ :year ])
+    assert_dom_equal expected, date_select("post", "written_on", order: [ :year ])
   end
 
   def test_date_select_without_day_with_separator
     @post = Post.new
     @post.written_on = Date.new(2004, 6, 15)
 
-    expected = "<input type=\"hidden\" id=\"post_written_on_3i\" name=\"post[written_on(3i)]\" value=\"1\" />\n"
+    expected = "<input type=\"hidden\" id=\"post_written_on_3i\" name=\"post[written_on(3i)]\" value=\"1\" />\n".dup
 
-    expected <<  %{<select id="post_written_on_2i" name="post[written_on(2i)]">\n}
+    expected << %{<select id="post_written_on_2i" name="post[written_on(2i)]">\n}
     expected << %{<option value="1">January</option>\n<option value="2">February</option>\n<option value="3">March</option>\n<option value="4">April</option>\n<option value="5">May</option>\n<option value="6" selected="selected">June</option>\n<option value="7">July</option>\n<option value="8">August</option>\n<option value="9">September</option>\n<option value="10">October</option>\n<option value="11">November</option>\n<option value="12">December</option>\n}
     expected << "</select>\n"
 
@@ -1886,16 +1911,16 @@ class DateHelperTest < ActionView::TestCase
     expected << %{<option value="1999">1999</option>\n<option value="2000">2000</option>\n<option value="2001">2001</option>\n<option value="2002">2002</option>\n<option value="2003">2003</option>\n<option value="2004" selected="selected">2004</option>\n<option value="2005">2005</option>\n<option value="2006">2006</option>\n<option value="2007">2007</option>\n<option value="2008">2008</option>\n<option value="2009">2009</option>\n}
     expected << "</select>\n"
 
-    assert_dom_equal expected, date_select("post", "written_on", :date_separator => '/', :order => [ :month, :year ])
+    assert_dom_equal expected, date_select("post", "written_on", date_separator: "/", order: [ :month, :year ])
   end
 
   def test_date_select_without_day_and_with_disabled_html_option
     @post = Post.new
     @post.written_on = Date.new(2004, 6, 15)
 
-    expected = "<input type=\"hidden\" id=\"post_written_on_3i\" disabled=\"disabled\" name=\"post[written_on(3i)]\" value=\"1\" />\n"
+    expected = "<input type=\"hidden\" id=\"post_written_on_3i\" disabled=\"disabled\" name=\"post[written_on(3i)]\" value=\"1\" />\n".dup
 
-    expected <<  %{<select id="post_written_on_2i" disabled="disabled" name="post[written_on(2i)]">\n}
+    expected << %{<select id="post_written_on_2i" disabled="disabled" name="post[written_on(2i)]">\n}
     expected << %{<option value="1">January</option>\n<option value="2">February</option>\n<option value="3">March</option>\n<option value="4">April</option>\n<option value="5">May</option>\n<option value="6" selected="selected">June</option>\n<option value="7">July</option>\n<option value="8">August</option>\n<option value="9">September</option>\n<option value="10">October</option>\n<option value="11">November</option>\n<option value="12">December</option>\n}
     expected << "</select>\n"
 
@@ -1903,7 +1928,7 @@ class DateHelperTest < ActionView::TestCase
     expected << %{<option value="1999">1999</option>\n<option value="2000">2000</option>\n<option value="2001">2001</option>\n<option value="2002">2002</option>\n<option value="2003">2003</option>\n<option value="2004" selected="selected">2004</option>\n<option value="2005">2005</option>\n<option value="2006">2006</option>\n<option value="2007">2007</option>\n<option value="2008">2008</option>\n<option value="2009">2009</option>\n}
     expected << "</select>\n"
 
-    assert_dom_equal expected, date_select("post", "written_on", { :order => [ :month, :year ] }, :disabled => true)
+    assert_dom_equal expected, date_select("post", "written_on", { order: [ :month, :year ] }, { disabled: true })
   end
 
   def test_date_select_within_fields_for
@@ -1914,7 +1939,7 @@ class DateHelperTest < ActionView::TestCase
       concat f.date_select(:written_on)
     end
 
-    expected = %{<select id="post_written_on_1i" name="post[written_on(1i)]">\n<option value="1999">1999</option>\n<option value="2000">2000</option>\n<option value="2001">2001</option>\n<option value="2002">2002</option>\n<option value="2003">2003</option>\n<option selected="selected" value="2004">2004</option>\n<option value="2005">2005</option>\n<option value="2006">2006</option>\n<option value="2007">2007</option>\n<option value="2008">2008</option>\n<option value="2009">2009</option>\n</select>\n}
+    expected = %{<select id="post_written_on_1i" name="post[written_on(1i)]">\n<option value="1999">1999</option>\n<option value="2000">2000</option>\n<option value="2001">2001</option>\n<option value="2002">2002</option>\n<option value="2003">2003</option>\n<option selected="selected" value="2004">2004</option>\n<option value="2005">2005</option>\n<option value="2006">2006</option>\n<option value="2007">2007</option>\n<option value="2008">2008</option>\n<option value="2009">2009</option>\n</select>\n}.dup
     expected << %{<select id="post_written_on_2i" name="post[written_on(2i)]">\n<option value="1">January</option>\n<option value="2">February</option>\n<option value="3">March</option>\n<option value="4">April</option>\n<option value="5">May</option>\n<option selected="selected" value="6">June</option>\n<option value="7">July</option>\n<option value="8">August</option>\n<option value="9">September</option>\n<option value="10">October</option>\n<option value="11">November</option>\n<option value="12">December</option>\n</select>\n}
     expected << %{<select id="post_written_on_3i" name="post[written_on(3i)]">\n<option value="1">1</option>\n<option value="2">2</option>\n<option value="3">3</option>\n<option value="4">4</option>\n<option value="5">5</option>\n<option value="6">6</option>\n<option value="7">7</option>\n<option value="8">8</option>\n<option value="9">9</option>\n<option value="10">10</option>\n<option value="11">11</option>\n<option value="12">12</option>\n<option value="13">13</option>\n<option value="14">14</option>\n<option selected="selected" value="15">15</option>\n<option value="16">16</option>\n<option value="17">17</option>\n<option value="18">18</option>\n<option value="19">19</option>\n<option value="20">20</option>\n<option value="21">21</option>\n<option value="22">22</option>\n<option value="23">23</option>\n<option value="24">24</option>\n<option value="25">25</option>\n<option value="26">26</option>\n<option value="27">27</option>\n<option value="28">28</option>\n<option value="29">29</option>\n<option value="30">30</option>\n<option value="31">31</option>\n</select>\n}
 
@@ -1926,11 +1951,11 @@ class DateHelperTest < ActionView::TestCase
     @post.written_on = Date.new(2004, 6, 15)
     id = 27
 
-    output_buffer = fields_for :post, @post, :index => id do |f|
+    output_buffer = fields_for :post, @post, index: id do |f|
       concat f.date_select(:written_on)
     end
 
-    expected = %{<select id="post_#{id}_written_on_1i" name="post[#{id}][written_on(1i)]">\n<option value="1999">1999</option>\n<option value="2000">2000</option>\n<option value="2001">2001</option>\n<option value="2002">2002</option>\n<option value="2003">2003</option>\n<option selected="selected" value="2004">2004</option>\n<option value="2005">2005</option>\n<option value="2006">2006</option>\n<option value="2007">2007</option>\n<option value="2008">2008</option>\n<option value="2009">2009</option>\n</select>\n}
+    expected = %{<select id="post_#{id}_written_on_1i" name="post[#{id}][written_on(1i)]">\n<option value="1999">1999</option>\n<option value="2000">2000</option>\n<option value="2001">2001</option>\n<option value="2002">2002</option>\n<option value="2003">2003</option>\n<option selected="selected" value="2004">2004</option>\n<option value="2005">2005</option>\n<option value="2006">2006</option>\n<option value="2007">2007</option>\n<option value="2008">2008</option>\n<option value="2009">2009</option>\n</select>\n}.dup
     expected << %{<select id="post_#{id}_written_on_2i" name="post[#{id}][written_on(2i)]">\n<option value="1">January</option>\n<option value="2">February</option>\n<option value="3">March</option>\n<option value="4">April</option>\n<option value="5">May</option>\n<option selected="selected" value="6">June</option>\n<option value="7">July</option>\n<option value="8">August</option>\n<option value="9">September</option>\n<option value="10">October</option>\n<option value="11">November</option>\n<option value="12">December</option>\n</select>\n}
     expected << %{<select id="post_#{id}_written_on_3i" name="post[#{id}][written_on(3i)]">\n<option value="1">1</option>\n<option value="2">2</option>\n<option value="3">3</option>\n<option value="4">4</option>\n<option value="5">5</option>\n<option value="6">6</option>\n<option value="7">7</option>\n<option value="8">8</option>\n<option value="9">9</option>\n<option value="10">10</option>\n<option value="11">11</option>\n<option value="12">12</option>\n<option value="13">13</option>\n<option value="14">14</option>\n<option selected="selected" value="15">15</option>\n<option value="16">16</option>\n<option value="17">17</option>\n<option value="18">18</option>\n<option value="19">19</option>\n<option value="20">20</option>\n<option value="21">21</option>\n<option value="22">22</option>\n<option value="23">23</option>\n<option value="24">24</option>\n<option value="25">25</option>\n<option value="26">26</option>\n<option value="27">27</option>\n<option value="28">28</option>\n<option value="29">29</option>\n<option value="30">30</option>\n<option value="31">31</option>\n</select>\n}
 
@@ -1942,12 +1967,11 @@ class DateHelperTest < ActionView::TestCase
     @post.written_on = Date.new(2004, 6, 15)
     id = nil
 
-    output_buffer = fields_for :post, @post, :index => id do |f|
+    output_buffer = fields_for :post, @post, index: id do |f|
       concat f.date_select(:written_on)
     end
 
-
-    expected = %{<select id="post_#{id}_written_on_1i" name="post[#{id}][written_on(1i)]">\n<option value="1999">1999</option>\n<option value="2000">2000</option>\n<option value="2001">2001</option>\n<option value="2002">2002</option>\n<option value="2003">2003</option>\n<option selected="selected" value="2004">2004</option>\n<option value="2005">2005</option>\n<option value="2006">2006</option>\n<option value="2007">2007</option>\n<option value="2008">2008</option>\n<option value="2009">2009</option>\n</select>\n}
+    expected = %{<select id="post_#{id}_written_on_1i" name="post[#{id}][written_on(1i)]">\n<option value="1999">1999</option>\n<option value="2000">2000</option>\n<option value="2001">2001</option>\n<option value="2002">2002</option>\n<option value="2003">2003</option>\n<option selected="selected" value="2004">2004</option>\n<option value="2005">2005</option>\n<option value="2006">2006</option>\n<option value="2007">2007</option>\n<option value="2008">2008</option>\n<option value="2009">2009</option>\n</select>\n}.dup
     expected << %{<select id="post_#{id}_written_on_2i" name="post[#{id}][written_on(2i)]">\n<option value="1">January</option>\n<option value="2">February</option>\n<option value="3">March</option>\n<option value="4">April</option>\n<option value="5">May</option>\n<option selected="selected" value="6">June</option>\n<option value="7">July</option>\n<option value="8">August</option>\n<option value="9">September</option>\n<option value="10">October</option>\n<option value="11">November</option>\n<option value="12">December</option>\n</select>\n}
     expected << %{<select id="post_#{id}_written_on_3i" name="post[#{id}][written_on(3i)]">\n<option value="1">1</option>\n<option value="2">2</option>\n<option value="3">3</option>\n<option value="4">4</option>\n<option value="5">5</option>\n<option value="6">6</option>\n<option value="7">7</option>\n<option value="8">8</option>\n<option value="9">9</option>\n<option value="10">10</option>\n<option value="11">11</option>\n<option value="12">12</option>\n<option value="13">13</option>\n<option value="14">14</option>\n<option selected="selected" value="15">15</option>\n<option value="16">16</option>\n<option value="17">17</option>\n<option value="18">18</option>\n<option value="19">19</option>\n<option value="20">20</option>\n<option value="21">21</option>\n<option value="22">22</option>\n<option value="23">23</option>\n<option value="24">24</option>\n<option value="25">25</option>\n<option value="26">26</option>\n<option value="27">27</option>\n<option value="28">28</option>\n<option value="29">29</option>\n<option value="30">30</option>\n<option value="31">31</option>\n</select>\n}
 
@@ -1959,7 +1983,7 @@ class DateHelperTest < ActionView::TestCase
     @post.written_on = Date.new(2004, 6, 15)
     id = 456
 
-    expected = %{<select id="post_456_written_on_1i" name="post[#{id}][written_on(1i)]">\n}
+    expected = %{<select id="post_456_written_on_1i" name="post[#{id}][written_on(1i)]">\n}.dup
     expected << %{<option value="1999">1999</option>\n<option value="2000">2000</option>\n<option value="2001">2001</option>\n<option value="2002">2002</option>\n<option value="2003">2003</option>\n<option value="2004" selected="selected">2004</option>\n<option value="2005">2005</option>\n<option value="2006">2006</option>\n<option value="2007">2007</option>\n<option value="2008">2008</option>\n<option value="2009">2009</option>\n}
     expected << "</select>\n"
 
@@ -1971,7 +1995,7 @@ class DateHelperTest < ActionView::TestCase
     expected << %{<option value="1">1</option>\n<option value="2">2</option>\n<option value="3">3</option>\n<option value="4">4</option>\n<option value="5">5</option>\n<option value="6">6</option>\n<option value="7">7</option>\n<option value="8">8</option>\n<option value="9">9</option>\n<option value="10">10</option>\n<option value="11">11</option>\n<option value="12">12</option>\n<option value="13">13</option>\n<option value="14">14</option>\n<option value="15" selected="selected">15</option>\n<option value="16">16</option>\n<option value="17">17</option>\n<option value="18">18</option>\n<option value="19">19</option>\n<option value="20">20</option>\n<option value="21">21</option>\n<option value="22">22</option>\n<option value="23">23</option>\n<option value="24">24</option>\n<option value="25">25</option>\n<option value="26">26</option>\n<option value="27">27</option>\n<option value="28">28</option>\n<option value="29">29</option>\n<option value="30">30</option>\n<option value="31">31</option>\n}
     expected << "</select>\n"
 
-    assert_dom_equal expected, date_select("post", "written_on", :index => id)
+    assert_dom_equal expected, date_select("post", "written_on", index: id)
   end
 
   def test_date_select_with_auto_index
@@ -1979,7 +2003,7 @@ class DateHelperTest < ActionView::TestCase
     @post.written_on = Date.new(2004, 6, 15)
     id = 123
 
-    expected = %{<select id="post_123_written_on_1i" name="post[#{id}][written_on(1i)]">\n}
+    expected = %{<select id="post_123_written_on_1i" name="post[#{id}][written_on(1i)]">\n}.dup
     expected << %{<option value="1999">1999</option>\n<option value="2000">2000</option>\n<option value="2001">2001</option>\n<option value="2002">2002</option>\n<option value="2003">2003</option>\n<option value="2004" selected="selected">2004</option>\n<option value="2005">2005</option>\n<option value="2006">2006</option>\n<option value="2007">2007</option>\n<option value="2008">2008</option>\n<option value="2009">2009</option>\n}
     expected << "</select>\n"
 
@@ -1998,7 +2022,7 @@ class DateHelperTest < ActionView::TestCase
     @post = Post.new
     @post.written_on = Date.new(2004, 6, 15)
 
-    expected =  %{<select id="post_written_on_3i" name="post[written_on(3i)]">\n}
+    expected = %{<select id="post_written_on_3i" name="post[written_on(3i)]">\n}.dup
     1.upto(31) { |i| expected << %(<option value="#{i}"#{' selected="selected"' if i == 15}>#{i}</option>\n) }
     expected << "</select>\n"
 
@@ -2006,19 +2030,19 @@ class DateHelperTest < ActionView::TestCase
     1.upto(12) { |i| expected << %(<option value="#{i}"#{' selected="selected"' if i == 6}>#{Date::MONTHNAMES[i]}</option>\n) }
     expected << "</select>\n"
 
-    expected <<  %{<select id="post_written_on_1i" name="post[written_on(1i)]">\n}
+    expected << %{<select id="post_written_on_1i" name="post[written_on(1i)]">\n}
     1999.upto(2009) { |i| expected << %(<option value="#{i}"#{' selected="selected"' if i == 2004}>#{i}</option>\n) }
     expected << "</select>\n"
 
-    assert_dom_equal expected, date_select("post", "written_on", :order => [:day, :month, :year])
+    assert_dom_equal expected, date_select("post", "written_on", order: [:day, :month, :year])
   end
 
   def test_date_select_with_nil
     @post = Post.new
 
-    start_year = Time.now.year-5
-    end_year   = Time.now.year+5
-    expected =   %{<select id="post_written_on_1i" name="post[written_on(1i)]">\n}
+    start_year = Time.now.year - 5
+    end_year   = Time.now.year + 5
+    expected =   %{<select id="post_written_on_1i" name="post[written_on(1i)]">\n}.dup
     start_year.upto(end_year) { |i| expected << %(<option value="#{i}"#{' selected="selected"' if i == Time.now.year}>#{i}</option>\n) }
     expected << "</select>\n"
 
@@ -2036,9 +2060,9 @@ class DateHelperTest < ActionView::TestCase
   def test_date_select_with_nil_and_blank
     @post = Post.new
 
-    start_year = Time.now.year-5
-    end_year   = Time.now.year+5
-    expected =   %{<select id="post_written_on_1i" name="post[written_on(1i)]">\n}
+    start_year = Time.now.year - 5
+    end_year   = Time.now.year + 5
+    expected =   %{<select id="post_written_on_1i" name="post[written_on(1i)]">\n}.dup
     expected << "<option value=\"\"></option>\n"
     start_year.upto(end_year) { |i| expected << %(<option value="#{i}">#{i}</option>\n) }
     expected << "</select>\n"
@@ -2053,17 +2077,17 @@ class DateHelperTest < ActionView::TestCase
     1.upto(31) { |i| expected << %(<option value="#{i}">#{i}</option>\n) }
     expected << "</select>\n"
 
-    assert_dom_equal expected, date_select("post", "written_on", :include_blank => true)
+    assert_dom_equal expected, date_select("post", "written_on", include_blank: true)
   end
 
   def test_date_select_with_nil_and_blank_and_order
     @post = Post.new
 
-    start_year = Time.now.year-5
-    end_year   = Time.now.year+5
+    start_year = Time.now.year - 5
+    end_year   = Time.now.year + 5
 
     expected = '<input name="post[written_on(3i)]" type="hidden" id="post_written_on_3i" value="1"/>' + "\n"
-    expected <<   %{<select id="post_written_on_1i" name="post[written_on(1i)]">\n}
+    expected << %{<select id="post_written_on_1i" name="post[written_on(1i)]">\n}
     expected << "<option value=\"\"></option>\n"
     start_year.upto(end_year) { |i| expected << %(<option value="#{i}">#{i}</option>\n) }
     expected << "</select>\n"
@@ -2073,23 +2097,23 @@ class DateHelperTest < ActionView::TestCase
     1.upto(12) { |i| expected << %(<option value="#{i}">#{Date::MONTHNAMES[i]}</option>\n) }
     expected << "</select>\n"
 
-    assert_dom_equal expected, date_select("post", "written_on", :order=>[:year, :month], :include_blank=>true)
+    assert_dom_equal expected, date_select("post", "written_on", order: [:year, :month], include_blank: true)
   end
 
   def test_date_select_with_nil_and_blank_and_discard_month
     @post = Post.new
 
-    start_year = Time.now.year-5
-    end_year   = Time.now.year+5
+    start_year = Time.now.year - 5
+    end_year   = Time.now.year + 5
 
-    expected = %{<select id="post_written_on_1i" name="post[written_on(1i)]">\n}
+    expected = %{<select id="post_written_on_1i" name="post[written_on(1i)]">\n}.dup
     expected << "<option value=\"\"></option>\n"
     start_year.upto(end_year) { |i| expected << %(<option value="#{i}">#{i}</option>\n) }
     expected << "</select>\n"
     expected << '<input name="post[written_on(2i)]" type="hidden" id="post_written_on_2i" value="1"/>' + "\n"
     expected << '<input name="post[written_on(3i)]" type="hidden" id="post_written_on_3i" value="1"/>' + "\n"
 
-    assert_dom_equal expected, date_select("post", "written_on", :discard_month => true, :include_blank=>true)
+    assert_dom_equal expected, date_select("post", "written_on", discard_month: true, include_blank: true)
   end
 
   def test_date_select_with_nil_and_blank_and_discard_year
@@ -2107,14 +2131,14 @@ class DateHelperTest < ActionView::TestCase
     1.upto(31) { |i| expected << %(<option value="#{i}">#{i}</option>\n) }
     expected << "</select>\n"
 
-    assert_dom_equal expected, date_select("post", "written_on", :discard_year => true, :include_blank=>true)
+    assert_dom_equal expected, date_select("post", "written_on", discard_year: true, include_blank: true)
   end
 
   def test_date_select_cant_override_discard_hour
     @post = Post.new
     @post.written_on = Date.new(2004, 6, 15)
 
-    expected = %{<select id="post_written_on_1i" name="post[written_on(1i)]">\n}
+    expected = %{<select id="post_written_on_1i" name="post[written_on(1i)]">\n}.dup
     expected << %{<option value="1999">1999</option>\n<option value="2000">2000</option>\n<option value="2001">2001</option>\n<option value="2002">2002</option>\n<option value="2003">2003</option>\n<option value="2004" selected="selected">2004</option>\n<option value="2005">2005</option>\n<option value="2006">2006</option>\n<option value="2007">2007</option>\n<option value="2008">2008</option>\n<option value="2009">2009</option>\n}
     expected << "</select>\n"
 
@@ -2126,14 +2150,14 @@ class DateHelperTest < ActionView::TestCase
     expected << %{<option value="1">1</option>\n<option value="2">2</option>\n<option value="3">3</option>\n<option value="4">4</option>\n<option value="5">5</option>\n<option value="6">6</option>\n<option value="7">7</option>\n<option value="8">8</option>\n<option value="9">9</option>\n<option value="10">10</option>\n<option value="11">11</option>\n<option value="12">12</option>\n<option value="13">13</option>\n<option value="14">14</option>\n<option value="15" selected="selected">15</option>\n<option value="16">16</option>\n<option value="17">17</option>\n<option value="18">18</option>\n<option value="19">19</option>\n<option value="20">20</option>\n<option value="21">21</option>\n<option value="22">22</option>\n<option value="23">23</option>\n<option value="24">24</option>\n<option value="25">25</option>\n<option value="26">26</option>\n<option value="27">27</option>\n<option value="28">28</option>\n<option value="29">29</option>\n<option value="30">30</option>\n<option value="31">31</option>\n}
     expected << "</select>\n"
 
-    assert_dom_equal expected, date_select("post", "written_on", :discard_hour => false)
+    assert_dom_equal expected, date_select("post", "written_on", discard_hour: false)
   end
 
   def test_date_select_with_html_options
     @post = Post.new
     @post.written_on = Date.new(2004, 6, 15)
 
-    expected = %{<select id="post_written_on_1i" name="post[written_on(1i)]" class="selector">\n}
+    expected = %{<select id="post_written_on_1i" name="post[written_on(1i)]" class="selector">\n}.dup
     expected << %{<option value="1999">1999</option>\n<option value="2000">2000</option>\n<option value="2001">2001</option>\n<option value="2002">2002</option>\n<option value="2003">2003</option>\n<option value="2004" selected="selected">2004</option>\n<option value="2005">2005</option>\n<option value="2006">2006</option>\n<option value="2007">2007</option>\n<option value="2008">2008</option>\n<option value="2009">2009</option>\n}
     expected << "</select>\n"
 
@@ -2146,7 +2170,7 @@ class DateHelperTest < ActionView::TestCase
 
     expected << "</select>\n"
 
-    assert_dom_equal expected, date_select("post", "written_on", {}, :class => 'selector')
+    assert_dom_equal expected, date_select("post", "written_on", {}, { class: "selector" })
   end
 
   def test_date_select_with_html_options_within_fields_for
@@ -2154,10 +2178,10 @@ class DateHelperTest < ActionView::TestCase
     @post.written_on = Date.new(2004, 6, 15)
 
     output_buffer = fields_for :post, @post do |f|
-      concat f.date_select(:written_on, {}, :class => 'selector')
+      concat f.date_select(:written_on, {}, { class: "selector" })
     end
 
-    expected = %{<select id="post_written_on_1i" name="post[written_on(1i)]" class="selector">\n}
+    expected = %{<select id="post_written_on_1i" name="post[written_on(1i)]" class="selector">\n}.dup
     expected << %{<option value="1999">1999</option>\n<option value="2000">2000</option>\n<option value="2001">2001</option>\n<option value="2002">2002</option>\n<option value="2003">2003</option>\n<option value="2004" selected="selected">2004</option>\n<option value="2005">2005</option>\n<option value="2006">2006</option>\n<option value="2007">2007</option>\n<option value="2008">2008</option>\n<option value="2009">2009</option>\n}
     expected << "</select>\n"
 
@@ -2177,7 +2201,7 @@ class DateHelperTest < ActionView::TestCase
     @post = Post.new
     @post.written_on = Date.new(2004, 6, 15)
 
-    expected = %{<select id="post_written_on_1i" name="post[written_on(1i)]">\n}
+    expected = %{<select id="post_written_on_1i" name="post[written_on(1i)]">\n}.dup
     expected << %{<option value="1999">1999</option>\n<option value="2000">2000</option>\n<option value="2001">2001</option>\n<option value="2002">2002</option>\n<option value="2003">2003</option>\n<option value="2004" selected="selected">2004</option>\n<option value="2005">2005</option>\n<option value="2006">2006</option>\n<option value="2007">2007</option>\n<option value="2008">2008</option>\n<option value="2009">2009</option>\n}
     expected << "</select>\n"
 
@@ -2194,14 +2218,14 @@ class DateHelperTest < ActionView::TestCase
 
     expected << "</select>\n"
 
-    assert_dom_equal expected, date_select("post", "written_on", { :date_separator => " / " })
+    assert_dom_equal expected, date_select("post", "written_on", date_separator: " / ")
   end
 
   def test_date_select_with_separator_and_order
     @post = Post.new
     @post.written_on = Date.new(2004, 6, 15)
 
-    expected = %{<select id="post_written_on_3i" name="post[written_on(3i)]">\n}
+    expected = %{<select id="post_written_on_3i" name="post[written_on(3i)]">\n}.dup
     expected << %{<option value="1">1</option>\n<option value="2">2</option>\n<option value="3">3</option>\n<option value="4">4</option>\n<option value="5">5</option>\n<option value="6">6</option>\n<option value="7">7</option>\n<option value="8">8</option>\n<option value="9">9</option>\n<option value="10">10</option>\n<option value="11">11</option>\n<option value="12">12</option>\n<option value="13">13</option>\n<option value="14">14</option>\n<option value="15" selected="selected">15</option>\n<option value="16">16</option>\n<option value="17">17</option>\n<option value="18">18</option>\n<option value="19">19</option>\n<option value="20">20</option>\n<option value="21">21</option>\n<option value="22">22</option>\n<option value="23">23</option>\n<option value="24">24</option>\n<option value="25">25</option>\n<option value="26">26</option>\n<option value="27">27</option>\n<option value="28">28</option>\n<option value="29">29</option>\n<option value="30">30</option>\n<option value="31">31</option>\n}
     expected << "</select>\n"
 
@@ -2217,14 +2241,14 @@ class DateHelperTest < ActionView::TestCase
     expected << %{<option value="1999">1999</option>\n<option value="2000">2000</option>\n<option value="2001">2001</option>\n<option value="2002">2002</option>\n<option value="2003">2003</option>\n<option value="2004" selected="selected">2004</option>\n<option value="2005">2005</option>\n<option value="2006">2006</option>\n<option value="2007">2007</option>\n<option value="2008">2008</option>\n<option value="2009">2009</option>\n}
     expected << "</select>\n"
 
-    assert_dom_equal expected, date_select("post", "written_on", { :order => [:day, :month, :year], :date_separator => " / " })
+    assert_dom_equal expected, date_select("post", "written_on", order: [:day, :month, :year], date_separator: " / ")
   end
 
   def test_date_select_with_separator_and_order_and_year_discarded
     @post = Post.new
     @post.written_on = Date.new(2004, 6, 15)
 
-    expected = %{<select id="post_written_on_3i" name="post[written_on(3i)]">\n}
+    expected = %{<select id="post_written_on_3i" name="post[written_on(3i)]">\n}.dup
     expected << %{<option value="1">1</option>\n<option value="2">2</option>\n<option value="3">3</option>\n<option value="4">4</option>\n<option value="5">5</option>\n<option value="6">6</option>\n<option value="7">7</option>\n<option value="8">8</option>\n<option value="9">9</option>\n<option value="10">10</option>\n<option value="11">11</option>\n<option value="12">12</option>\n<option value="13">13</option>\n<option value="14">14</option>\n<option value="15" selected="selected">15</option>\n<option value="16">16</option>\n<option value="17">17</option>\n<option value="18">18</option>\n<option value="19">19</option>\n<option value="20">20</option>\n<option value="21">21</option>\n<option value="22">22</option>\n<option value="23">23</option>\n<option value="24">24</option>\n<option value="25">25</option>\n<option value="26">26</option>\n<option value="27">27</option>\n<option value="28">28</option>\n<option value="29">29</option>\n<option value="30">30</option>\n<option value="31">31</option>\n}
     expected << "</select>\n"
 
@@ -2235,14 +2259,14 @@ class DateHelperTest < ActionView::TestCase
     expected << "</select>\n"
     expected << %{<input type="hidden" id="post_written_on_1i" name="post[written_on(1i)]" value="2004" />\n}
 
-    assert_dom_equal expected, date_select("post", "written_on", { :order => [:day, :month, :year], :discard_year => true, :date_separator => " / " })
+    assert_dom_equal expected, date_select("post", "written_on", order: [:day, :month, :year], discard_year: true, date_separator: " / ")
   end
 
   def test_date_select_with_default_prompt
     @post = Post.new
     @post.written_on = Date.new(2004, 6, 15)
 
-    expected = %{<select id="post_written_on_1i" name="post[written_on(1i)]">\n}
+    expected = %{<select id="post_written_on_1i" name="post[written_on(1i)]">\n}.dup
     expected << %{<option value="">Year</option>\n<option value="1999">1999</option>\n<option value="2000">2000</option>\n<option value="2001">2001</option>\n<option value="2002">2002</option>\n<option value="2003">2003</option>\n<option value="2004" selected="selected">2004</option>\n<option value="2005">2005</option>\n<option value="2006">2006</option>\n<option value="2007">2007</option>\n<option value="2008">2008</option>\n<option value="2009">2009</option>\n}
     expected << "</select>\n"
 
@@ -2255,14 +2279,14 @@ class DateHelperTest < ActionView::TestCase
 
     expected << "</select>\n"
 
-    assert_dom_equal expected, date_select("post", "written_on", :prompt => true)
+    assert_dom_equal expected, date_select("post", "written_on", prompt: true)
   end
 
   def test_date_select_with_custom_prompt
     @post = Post.new
     @post.written_on = Date.new(2004, 6, 15)
 
-    expected = %{<select id="post_written_on_1i" name="post[written_on(1i)]">\n}
+    expected = %{<select id="post_written_on_1i" name="post[written_on(1i)]">\n}.dup
     expected << %{<option value="">Choose year</option>\n<option value="1999">1999</option>\n<option value="2000">2000</option>\n<option value="2001">2001</option>\n<option value="2002">2002</option>\n<option value="2003">2003</option>\n<option value="2004" selected="selected">2004</option>\n<option value="2005">2005</option>\n<option value="2006">2006</option>\n<option value="2007">2007</option>\n<option value="2008">2008</option>\n<option value="2009">2009</option>\n}
     expected << "</select>\n"
 
@@ -2275,14 +2299,14 @@ class DateHelperTest < ActionView::TestCase
 
     expected << "</select>\n"
 
-    assert_dom_equal expected, date_select("post", "written_on", :prompt => {:year => 'Choose year', :month => 'Choose month', :day => 'Choose day'})
+    assert_dom_equal expected, date_select("post", "written_on", prompt: { year: "Choose year", month: "Choose month", day: "Choose day" })
   end
 
   def test_date_select_with_generic_with_css_classes
     @post = Post.new
     @post.written_on = Date.new(2004, 6, 15)
 
-    expected = %{<select id="post_written_on_1i" name="post[written_on(1i)]" class="year">\n}
+    expected = %{<select id="post_written_on_1i" name="post[written_on(1i)]" class="year">\n}.dup
     expected << %{<option value="1999">1999</option>\n<option value="2000">2000</option>\n<option value="2001">2001</option>\n<option value="2002">2002</option>\n<option value="2003">2003</option>\n<option value="2004" selected="selected">2004</option>\n<option value="2005">2005</option>\n<option value="2006">2006</option>\n<option value="2007">2007</option>\n<option value="2008">2008</option>\n<option value="2009">2009</option>\n}
     expected << "</select>\n"
 
@@ -2302,7 +2326,7 @@ class DateHelperTest < ActionView::TestCase
     @post = Post.new
     @post.written_on = Date.new(2004, 6, 15)
 
-    expected = %{<select id="post_written_on_1i" name="post[written_on(1i)]" class="my-year">\n}
+    expected = %{<select id="post_written_on_1i" name="post[written_on(1i)]" class="my-year">\n}.dup
     expected << %{<option value="1999">1999</option>\n<option value="2000">2000</option>\n<option value="2001">2001</option>\n<option value="2002">2002</option>\n<option value="2003">2003</option>\n<option value="2004" selected="selected">2004</option>\n<option value="2005">2005</option>\n<option value="2006">2006</option>\n<option value="2007">2007</option>\n<option value="2008">2008</option>\n<option value="2009">2009</option>\n}
     expected << "</select>\n"
 
@@ -2315,14 +2339,14 @@ class DateHelperTest < ActionView::TestCase
 
     expected << "</select>\n"
 
-    assert_dom_equal expected, date_select("post", "written_on", with_css_classes: { year: 'my-year', month: 'my-month', day: 'my-day' })
+    assert_dom_equal expected, date_select("post", "written_on", with_css_classes: { year: "my-year", month: "my-month", day: "my-day" })
   end
 
   def test_time_select
     @post = Post.new
     @post.written_on = Time.local(2004, 6, 15, 15, 16, 35)
 
-    expected = %{<input type="hidden" id="post_written_on_1i" name="post[written_on(1i)]" value="2004" />\n}
+    expected = %{<input type="hidden" id="post_written_on_1i" name="post[written_on(1i)]" value="2004" />\n}.dup
     expected << %{<input type="hidden" id="post_written_on_2i" name="post[written_on(2i)]" value="6" />\n}
     expected << %{<input type="hidden" id="post_written_on_3i" name="post[written_on(3i)]" value="15" />\n}
 
@@ -2341,7 +2365,7 @@ class DateHelperTest < ActionView::TestCase
     @post = Post.new
     @post.written_on = Time.local(2004, 6, 15, 15, 16, 35)
 
-    expected = %{<input type="hidden" id="post_written_on_1i" name="post[written_on(1i)]" value="2004" />\n}
+    expected = %{<input type="hidden" id="post_written_on_1i" name="post[written_on(1i)]" value="2004" />\n}.dup
     expected << %{<input type="hidden" id="post_written_on_2i" name="post[written_on(2i)]" value="6" />\n}
     expected << %{<input type="hidden" id="post_written_on_3i" name="post[written_on(3i)]" value="15" />\n}
 
@@ -2360,7 +2384,7 @@ class DateHelperTest < ActionView::TestCase
     @post = Post.new
     @post.written_on = Time.local(2004, 6, 15, 15, 16, 35)
 
-    expected = %{<input type="hidden" id="post_written_on_1i" name="post[written_on(1i)]" value="1" />\n}
+    expected = %{<input type="hidden" id="post_written_on_1i" name="post[written_on(1i)]" value="1" />\n}.dup
     expected << %{<input type="hidden" id="post_written_on_2i" name="post[written_on(2i)]" value="1" />\n}
     expected << %{<input type="hidden" id="post_written_on_3i" name="post[written_on(3i)]" value="1" />\n}
 
@@ -2379,7 +2403,7 @@ class DateHelperTest < ActionView::TestCase
     @post = Post.new
     @post.written_on = Time.local(2004, 6, 15, 15, 16, 35)
 
-    expected = %(<select id="post_written_on_4i" name="post[written_on(4i)]">\n)
+    expected = %(<select id="post_written_on_4i" name="post[written_on(4i)]">\n).dup
     0.upto(23) { |i| expected << %(<option value="#{sprintf("%02d", i)}"#{' selected="selected"' if i == 15}>#{sprintf("%02d", i)}</option>\n) }
     expected << "</select>\n"
     expected << " : "
@@ -2387,14 +2411,14 @@ class DateHelperTest < ActionView::TestCase
     0.upto(59) { |i| expected << %(<option value="#{sprintf("%02d", i)}"#{' selected="selected"' if i == 16}>#{sprintf("%02d", i)}</option>\n) }
     expected << "</select>\n"
 
-    assert_dom_equal expected, time_select("post", "written_on", :ignore_date => true)
+    assert_dom_equal expected, time_select("post", "written_on", ignore_date: true)
   end
 
   def test_time_select_with_seconds
     @post = Post.new
     @post.written_on = Time.local(2004, 6, 15, 15, 16, 35)
 
-    expected = %{<input type="hidden" id="post_written_on_1i" name="post[written_on(1i)]" value="2004" />\n}
+    expected = %{<input type="hidden" id="post_written_on_1i" name="post[written_on(1i)]" value="2004" />\n}.dup
     expected << %{<input type="hidden" id="post_written_on_2i" name="post[written_on(2i)]" value="6" />\n}
     expected << %{<input type="hidden" id="post_written_on_3i" name="post[written_on(3i)]" value="15" />\n}
 
@@ -2410,14 +2434,14 @@ class DateHelperTest < ActionView::TestCase
     0.upto(59) { |i| expected << %(<option value="#{sprintf("%02d", i)}"#{' selected="selected"' if i == 35}>#{sprintf("%02d", i)}</option>\n) }
     expected << "</select>\n"
 
-    assert_dom_equal expected, time_select("post", "written_on", :include_seconds => true)
+    assert_dom_equal expected, time_select("post", "written_on", include_seconds: true)
   end
 
   def test_time_select_with_html_options
     @post = Post.new
     @post.written_on = Time.local(2004, 6, 15, 15, 16, 35)
 
-    expected = %{<input type="hidden" id="post_written_on_1i" name="post[written_on(1i)]" value="2004" />\n}
+    expected = %{<input type="hidden" id="post_written_on_1i" name="post[written_on(1i)]" value="2004" />\n}.dup
     expected << %{<input type="hidden" id="post_written_on_2i" name="post[written_on(2i)]" value="6" />\n}
     expected << %{<input type="hidden" id="post_written_on_3i" name="post[written_on(3i)]" value="15" />\n}
 
@@ -2429,7 +2453,7 @@ class DateHelperTest < ActionView::TestCase
     0.upto(59) { |i| expected << %(<option value="#{sprintf("%02d", i)}"#{' selected="selected"' if i == 16}>#{sprintf("%02d", i)}</option>\n) }
     expected << "</select>\n"
 
-    assert_dom_equal expected, time_select("post", "written_on", {}, :class => 'selector')
+    assert_dom_equal expected, time_select("post", "written_on", {}, { class: "selector" })
   end
 
   def test_time_select_with_html_options_within_fields_for
@@ -2437,10 +2461,10 @@ class DateHelperTest < ActionView::TestCase
     @post.written_on = Time.local(2004, 6, 15, 15, 16, 35)
 
     output_buffer = fields_for :post, @post do |f|
-      concat f.time_select(:written_on, {}, :class => 'selector')
+      concat f.time_select(:written_on, {}, { class: "selector" })
     end
 
-    expected = %{<input type="hidden" id="post_written_on_1i" name="post[written_on(1i)]" value="2004" />\n}
+    expected = %{<input type="hidden" id="post_written_on_1i" name="post[written_on(1i)]" value="2004" />\n}.dup
     expected << %{<input type="hidden" id="post_written_on_2i" name="post[written_on(2i)]" value="6" />\n}
     expected << %{<input type="hidden" id="post_written_on_3i" name="post[written_on(3i)]" value="15" />\n}
 
@@ -2459,7 +2483,7 @@ class DateHelperTest < ActionView::TestCase
     @post = Post.new
     @post.written_on = Time.local(2004, 6, 15, 15, 16, 35)
 
-    expected = %{<input type="hidden" id="post_written_on_1i" name="post[written_on(1i)]" value="2004" />\n}
+    expected = %{<input type="hidden" id="post_written_on_1i" name="post[written_on(1i)]" value="2004" />\n}.dup
     expected << %{<input type="hidden" id="post_written_on_2i" name="post[written_on(2i)]" value="6" />\n}
     expected << %{<input type="hidden" id="post_written_on_3i" name="post[written_on(3i)]" value="15" />\n}
 
@@ -2479,14 +2503,14 @@ class DateHelperTest < ActionView::TestCase
     0.upto(59) { |i| expected << %(<option value="#{sprintf("%02d", i)}"#{' selected="selected"' if i == 35}>#{sprintf("%02d", i)}</option>\n) }
     expected << "</select>\n"
 
-    assert_dom_equal expected, time_select("post", "written_on", { :time_separator => " - ", :include_seconds => true })
+    assert_dom_equal expected, time_select("post", "written_on", time_separator: " - ", include_seconds: true)
   end
 
   def test_time_select_with_default_prompt
     @post = Post.new
     @post.written_on = Time.local(2004, 6, 15, 15, 16, 35)
 
-    expected = %{<input type="hidden" id="post_written_on_1i" name="post[written_on(1i)]" value="2004" />\n}
+    expected = %{<input type="hidden" id="post_written_on_1i" name="post[written_on(1i)]" value="2004" />\n}.dup
     expected << %{<input type="hidden" id="post_written_on_2i" name="post[written_on(2i)]" value="6" />\n}
     expected << %{<input type="hidden" id="post_written_on_3i" name="post[written_on(3i)]" value="15" />\n}
 
@@ -2496,18 +2520,18 @@ class DateHelperTest < ActionView::TestCase
     expected << "</select>\n"
     expected << " : "
     expected << %(<select id="post_written_on_5i" name="post[written_on(5i)]">\n)
-        expected << %(<option value="">Minute</option>\n)
+    expected << %(<option value="">Minute</option>\n)
     0.upto(59) { |i| expected << %(<option value="#{sprintf("%02d", i)}"#{' selected="selected"' if i == 16}>#{sprintf("%02d", i)}</option>\n) }
     expected << "</select>\n"
 
-    assert_dom_equal expected, time_select("post", "written_on", :prompt => true)
+    assert_dom_equal expected, time_select("post", "written_on", prompt: true)
   end
 
   def test_time_select_with_custom_prompt
     @post = Post.new
     @post.written_on = Time.local(2004, 6, 15, 15, 16, 35)
 
-    expected = %{<input type="hidden" id="post_written_on_1i" name="post[written_on(1i)]" value="2004" />\n}
+    expected = %{<input type="hidden" id="post_written_on_1i" name="post[written_on(1i)]" value="2004" />\n}.dup
     expected << %{<input type="hidden" id="post_written_on_2i" name="post[written_on(2i)]" value="6" />\n}
     expected << %{<input type="hidden" id="post_written_on_3i" name="post[written_on(3i)]" value="15" />\n}
 
@@ -2517,18 +2541,18 @@ class DateHelperTest < ActionView::TestCase
     expected << "</select>\n"
     expected << " : "
     expected << %(<select id="post_written_on_5i" name="post[written_on(5i)]">\n)
-        expected << %(<option value="">Choose minute</option>\n)
+    expected << %(<option value="">Choose minute</option>\n)
     0.upto(59) { |i| expected << %(<option value="#{sprintf("%02d", i)}"#{' selected="selected"' if i == 16}>#{sprintf("%02d", i)}</option>\n) }
     expected << "</select>\n"
 
-    assert_dom_equal expected, time_select("post", "written_on", :prompt => {:hour => 'Choose hour', :minute => 'Choose minute'})
+    assert_dom_equal expected, time_select("post", "written_on", prompt: { hour: "Choose hour", minute: "Choose minute" })
   end
 
   def test_time_select_with_generic_with_css_classes
     @post = Post.new
     @post.written_on = Time.local(2004, 6, 15, 15, 16, 35)
 
-    expected = %{<input type="hidden" id="post_written_on_1i" name="post[written_on(1i)]" value="2004" />\n}
+    expected = %{<input type="hidden" id="post_written_on_1i" name="post[written_on(1i)]" value="2004" />\n}.dup
     expected << %{<input type="hidden" id="post_written_on_2i" name="post[written_on(2i)]" value="6" />\n}
     expected << %{<input type="hidden" id="post_written_on_3i" name="post[written_on(3i)]" value="15" />\n}
 
@@ -2549,7 +2573,7 @@ class DateHelperTest < ActionView::TestCase
     @post = Post.new
     @post.written_on = Time.local(2004, 6, 15, 15, 16, 35)
 
-    expected = %{<input type="hidden" id="post_written_on_1i" name="post[written_on(1i)]" value="2004" />\n}
+    expected = %{<input type="hidden" id="post_written_on_1i" name="post[written_on(1i)]" value="2004" />\n}.dup
     expected << %{<input type="hidden" id="post_written_on_2i" name="post[written_on(2i)]" value="6" />\n}
     expected << %{<input type="hidden" id="post_written_on_3i" name="post[written_on(3i)]" value="15" />\n}
 
@@ -2563,14 +2587,14 @@ class DateHelperTest < ActionView::TestCase
     0.upto(59) { |i| expected << %(<option value="#{sprintf("%02d", i)}"#{' selected="selected"' if i == 16}>#{sprintf("%02d", i)}</option>\n) }
     expected << "</select>\n"
 
-    assert_dom_equal expected, time_select("post", "written_on", with_css_classes: { hour: 'my-hour', minute: 'my-minute' })
+    assert_dom_equal expected, time_select("post", "written_on", with_css_classes: { hour: "my-hour", minute: "my-minute" })
   end
 
   def test_time_select_with_disabled_html_option
     @post = Post.new
     @post.written_on = Time.local(2004, 6, 15, 15, 16, 35)
 
-    expected = %{<input type="hidden" id="post_written_on_1i" disabled="disabled" name="post[written_on(1i)]" value="2004" />\n}
+    expected = %{<input type="hidden" id="post_written_on_1i" disabled="disabled" name="post[written_on(1i)]" value="2004" />\n}.dup
     expected << %{<input type="hidden" id="post_written_on_2i" disabled="disabled" name="post[written_on(2i)]" value="6" />\n}
     expected << %{<input type="hidden" id="post_written_on_3i" disabled="disabled" name="post[written_on(3i)]" value="15" />\n}
 
@@ -2582,14 +2606,14 @@ class DateHelperTest < ActionView::TestCase
     0.upto(59) { |i| expected << %(<option value="#{sprintf("%02d", i)}"#{' selected="selected"' if i == 16}>#{sprintf("%02d", i)}</option>\n) }
     expected << "</select>\n"
 
-    assert_dom_equal expected, time_select("post", "written_on", {}, :disabled => true)
+    assert_dom_equal expected, time_select("post", "written_on", {}, { disabled: true })
   end
 
   def test_datetime_select
     @post = Post.new
     @post.updated_at = Time.local(2004, 6, 15, 16, 35)
 
-    expected = %{<select id="post_updated_at_1i" name="post[updated_at(1i)]">\n}
+    expected = %{<select id="post_updated_at_1i" name="post[updated_at(1i)]">\n}.dup
     expected << %{<option value="1999">1999</option>\n<option value="2000">2000</option>\n<option value="2001">2001</option>\n<option value="2002">2002</option>\n<option value="2003">2003</option>\n<option value="2004" selected="selected">2004</option>\n<option value="2005">2005</option>\n<option value="2006">2006</option>\n<option value="2007">2007</option>\n<option value="2008">2008</option>\n<option value="2009">2009</option>\n}
     expected << "</select>\n"
 
@@ -2618,7 +2642,7 @@ class DateHelperTest < ActionView::TestCase
     @post = Post.new
     @post.updated_at = Time.local(2004, 6, 15, 16, 35)
 
-    expected = %{<select id="post_updated_at_1i" name="post[updated_at(1i)]">\n}
+    expected = %{<select id="post_updated_at_1i" name="post[updated_at(1i)]">\n}.dup
     expected << %{<option value="1999">1999</option>\n<option value="2000">2000</option>\n<option value="2001">2001</option>\n<option value="2002">2002</option>\n<option value="2003">2003</option>\n<option value="2004" selected="selected">2004</option>\n<option value="2005">2005</option>\n<option value="2006">2006</option>\n<option value="2007">2007</option>\n<option value="2008">2008</option>\n<option value="2009">2009</option>\n}
     expected << "</select>\n"
 
@@ -2640,7 +2664,7 @@ class DateHelperTest < ActionView::TestCase
     expected << %{<option value="00">00</option>\n<option value="01">01</option>\n<option value="02">02</option>\n<option value="03">03</option>\n<option value="04">04</option>\n<option value="05">05</option>\n<option value="06">06</option>\n<option value="07">07</option>\n<option value="08">08</option>\n<option value="09">09</option>\n<option value="10">10</option>\n<option value="11">11</option>\n<option value="12">12</option>\n<option value="13">13</option>\n<option value="14">14</option>\n<option value="15">15</option>\n<option value="16">16</option>\n<option value="17">17</option>\n<option value="18">18</option>\n<option value="19">19</option>\n<option value="20">20</option>\n<option value="21">21</option>\n<option value="22">22</option>\n<option value="23">23</option>\n<option value="24">24</option>\n<option value="25">25</option>\n<option value="26">26</option>\n<option value="27">27</option>\n<option value="28">28</option>\n<option value="29">29</option>\n<option value="30" selected="selected">30</option>\n<option value="31">31</option>\n<option value="32">32</option>\n<option value="33">33</option>\n<option value="34">34</option>\n<option value="35">35</option>\n<option value="36">36</option>\n<option value="37">37</option>\n<option value="38">38</option>\n<option value="39">39</option>\n<option value="40">40</option>\n<option value="41">41</option>\n<option value="42">42</option>\n<option value="43">43</option>\n<option value="44">44</option>\n<option value="45">45</option>\n<option value="46">46</option>\n<option value="47">47</option>\n<option value="48">48</option>\n<option value="49">49</option>\n<option value="50">50</option>\n<option value="51">51</option>\n<option value="52">52</option>\n<option value="53">53</option>\n<option value="54">54</option>\n<option value="55">55</option>\n<option value="56">56</option>\n<option value="57">57</option>\n<option value="58">58</option>\n<option value="59">59</option>\n}
     expected << "</select>\n"
 
-    assert_dom_equal expected, datetime_select("post", "updated_at", :selected => Time.local(2004, 3, 10, 12, 30))
+    assert_dom_equal expected, datetime_select("post", "updated_at", selected: Time.local(2004, 3, 10, 12, 30))
   end
 
   def test_datetime_select_with_selected_nil
@@ -2674,7 +2698,7 @@ class DateHelperTest < ActionView::TestCase
     # The love zone is UTC+0
     mytz = Class.new(ActiveSupport::TimeZone) {
       attr_accessor :now
-    }.create('tenderlove', 0, ActiveSupport::TimeZone.find_tzinfo('UTC'))
+    }.create("tenderlove", 0, ActiveSupport::TimeZone.find_tzinfo("UTC"))
 
     now       = Time.mktime(2004, 6, 15, 16, 35, 0)
     mytz.now  = now
@@ -2684,7 +2708,7 @@ class DateHelperTest < ActionView::TestCase
 
     @post = Post.new
 
-    expected = %{<select id="post_updated_at_1i" name="post[updated_at(1i)]">\n}
+    expected = %{<select id="post_updated_at_1i" name="post[updated_at(1i)]">\n}.dup
     expected << %{<option value="1999">1999</option>\n<option value="2000">2000</option>\n<option value="2001">2001</option>\n<option value="2002">2002</option>\n<option value="2003">2003</option>\n<option value="2004" selected="selected">2004</option>\n<option value="2005">2005</option>\n<option value="2006">2006</option>\n<option value="2007">2007</option>\n<option value="2008">2008</option>\n<option value="2009">2009</option>\n}
     expected << "</select>\n"
 
@@ -2716,10 +2740,10 @@ class DateHelperTest < ActionView::TestCase
     @post.updated_at = Time.local(2004, 6, 15, 16, 35)
 
     output_buffer = fields_for :post, @post do |f|
-      concat f.datetime_select(:updated_at, {}, :class => 'selector')
+      concat f.datetime_select(:updated_at, {}, { class: "selector" })
     end
 
-    expected = %{<select id="post_updated_at_1i" name="post[updated_at(1i)]" class="selector">\n<option value="1999">1999</option>\n<option value="2000">2000</option>\n<option value="2001">2001</option>\n<option value="2002">2002</option>\n<option value="2003">2003</option>\n<option selected="selected" value="2004">2004</option>\n<option value="2005">2005</option>\n<option value="2006">2006</option>\n<option value="2007">2007</option>\n<option value="2008">2008</option>\n<option value="2009">2009</option>\n</select>\n}
+    expected = %{<select id="post_updated_at_1i" name="post[updated_at(1i)]" class="selector">\n<option value="1999">1999</option>\n<option value="2000">2000</option>\n<option value="2001">2001</option>\n<option value="2002">2002</option>\n<option value="2003">2003</option>\n<option selected="selected" value="2004">2004</option>\n<option value="2005">2005</option>\n<option value="2006">2006</option>\n<option value="2007">2007</option>\n<option value="2008">2008</option>\n<option value="2009">2009</option>\n</select>\n}.dup
     expected << %{<select id="post_updated_at_2i" name="post[updated_at(2i)]" class="selector">\n<option value="1">January</option>\n<option value="2">February</option>\n<option value="3">March</option>\n<option value="4">April</option>\n<option value="5">May</option>\n<option selected="selected" value="6">June</option>\n<option value="7">July</option>\n<option value="8">August</option>\n<option value="9">September</option>\n<option value="10">October</option>\n<option value="11">November</option>\n<option value="12">December</option>\n</select>\n}
     expected << %{<select id="post_updated_at_3i" name="post[updated_at(3i)]" class="selector">\n<option value="1">1</option>\n<option value="2">2</option>\n<option value="3">3</option>\n<option value="4">4</option>\n<option value="5">5</option>\n<option value="6">6</option>\n<option value="7">7</option>\n<option value="8">8</option>\n<option value="9">9</option>\n<option value="10">10</option>\n<option value="11">11</option>\n<option value="12">12</option>\n<option value="13">13</option>\n<option value="14">14</option>\n<option selected="selected" value="15">15</option>\n<option value="16">16</option>\n<option value="17">17</option>\n<option value="18">18</option>\n<option value="19">19</option>\n<option value="20">20</option>\n<option value="21">21</option>\n<option value="22">22</option>\n<option value="23">23</option>\n<option value="24">24</option>\n<option value="25">25</option>\n<option value="26">26</option>\n<option value="27">27</option>\n<option value="28">28</option>\n<option value="29">29</option>\n<option value="30">30</option>\n<option value="31">31</option>\n</select>\n}
     expected << %{ &mdash; <select id="post_updated_at_4i" name="post[updated_at(4i)]" class="selector">\n<option value="00">00</option>\n<option value="01">01</option>\n<option value="02">02</option>\n<option value="03">03</option>\n<option value="04">04</option>\n<option value="05">05</option>\n<option value="06">06</option>\n<option value="07">07</option>\n<option value="08">08</option>\n<option value="09">09</option>\n<option value="10">10</option>\n<option value="11">11</option>\n<option value="12">12</option>\n<option value="13">13</option>\n<option value="14">14</option>\n<option value="15">15</option>\n<option selected="selected" value="16">16</option>\n<option value="17">17</option>\n<option value="18">18</option>\n<option value="19">19</option>\n<option value="20">20</option>\n<option value="21">21</option>\n<option value="22">22</option>\n<option value="23">23</option>\n</select>\n}
@@ -2732,7 +2756,7 @@ class DateHelperTest < ActionView::TestCase
     @post = Post.new
     @post.updated_at = Time.local(2004, 6, 15, 15, 16, 35)
 
-    expected = %{<select id="post_updated_at_1i" name="post[updated_at(1i)]">\n}
+    expected = %{<select id="post_updated_at_1i" name="post[updated_at(1i)]">\n}.dup
     expected << %{<option value="1999">1999</option>\n<option value="2000">2000</option>\n<option value="2001">2001</option>\n<option value="2002">2002</option>\n<option value="2003">2003</option>\n<option value="2004" selected="selected">2004</option>\n<option value="2005">2005</option>\n<option value="2006">2006</option>\n<option value="2007">2007</option>\n<option value="2008">2008</option>\n<option value="2009">2009</option>\n}
     expected << "</select>\n"
 
@@ -2766,7 +2790,7 @@ class DateHelperTest < ActionView::TestCase
     0.upto(59) { |i| expected << %(<option value="#{sprintf("%02d", i)}"#{' selected="selected"' if i == 35}>#{sprintf("%02d", i)}</option>\n) }
     expected << "</select>\n"
 
-    assert_dom_equal expected, datetime_select("post", "updated_at", { :date_separator => " / ", :datetime_separator => " , ", :time_separator => " - ", :include_seconds => true })
+    assert_dom_equal expected, datetime_select("post", "updated_at", date_separator: " / ", datetime_separator: " , ", time_separator: " - ", include_seconds: true)
   end
 
   def test_datetime_select_with_integer
@@ -2777,7 +2801,7 @@ class DateHelperTest < ActionView::TestCase
 
   def test_datetime_select_with_infinity # Float
     @post = Post.new
-    @post.updated_at = (-1.0/0)
+    @post.updated_at = (-1.0 / 0)
     datetime_select("post", "updated_at")
   end
 
@@ -2785,7 +2809,7 @@ class DateHelperTest < ActionView::TestCase
     @post = Post.new
     @post.updated_at = nil
 
-    expected = %{<select id="post_updated_at_1i" name="post[updated_at(1i)]">\n}
+    expected = %{<select id="post_updated_at_1i" name="post[updated_at(1i)]">\n}.dup
     expected << %{<option value="">Year</option>\n<option value="1999">1999</option>\n<option value="2000">2000</option>\n<option value="2001">2001</option>\n<option value="2002">2002</option>\n<option value="2003">2003</option>\n<option value="2004">2004</option>\n<option value="2005">2005</option>\n<option value="2006">2006</option>\n<option value="2007">2007</option>\n<option value="2008">2008</option>\n<option value="2009">2009</option>\n}
     expected << "</select>\n"
 
@@ -2807,14 +2831,14 @@ class DateHelperTest < ActionView::TestCase
     expected << %{<option value="">Minute</option>\n<option value="00">00</option>\n<option value="01">01</option>\n<option value="02">02</option>\n<option value="03">03</option>\n<option value="04">04</option>\n<option value="05">05</option>\n<option value="06">06</option>\n<option value="07">07</option>\n<option value="08">08</option>\n<option value="09">09</option>\n<option value="10">10</option>\n<option value="11">11</option>\n<option value="12">12</option>\n<option value="13">13</option>\n<option value="14">14</option>\n<option value="15">15</option>\n<option value="16">16</option>\n<option value="17">17</option>\n<option value="18">18</option>\n<option value="19">19</option>\n<option value="20">20</option>\n<option value="21">21</option>\n<option value="22">22</option>\n<option value="23">23</option>\n<option value="24">24</option>\n<option value="25">25</option>\n<option value="26">26</option>\n<option value="27">27</option>\n<option value="28">28</option>\n<option value="29">29</option>\n<option value="30">30</option>\n<option value="31">31</option>\n<option value="32">32</option>\n<option value="33">33</option>\n<option value="34">34</option>\n<option value="35">35</option>\n<option value="36">36</option>\n<option value="37">37</option>\n<option value="38">38</option>\n<option value="39">39</option>\n<option value="40">40</option>\n<option value="41">41</option>\n<option value="42">42</option>\n<option value="43">43</option>\n<option value="44">44</option>\n<option value="45">45</option>\n<option value="46">46</option>\n<option value="47">47</option>\n<option value="48">48</option>\n<option value="49">49</option>\n<option value="50">50</option>\n<option value="51">51</option>\n<option value="52">52</option>\n<option value="53">53</option>\n<option value="54">54</option>\n<option value="55">55</option>\n<option value="56">56</option>\n<option value="57">57</option>\n<option value="58">58</option>\n<option value="59">59</option>\n}
     expected << "</select>\n"
 
-    assert_dom_equal expected, datetime_select("post", "updated_at", :start_year=>1999, :end_year=>2009,  :prompt => true)
+    assert_dom_equal expected, datetime_select("post", "updated_at", start_year: 1999, end_year: 2009,  prompt: true)
   end
 
   def test_datetime_select_with_custom_prompt
     @post = Post.new
     @post.updated_at = nil
 
-    expected = %{<select id="post_updated_at_1i" name="post[updated_at(1i)]">\n}
+    expected = %{<select id="post_updated_at_1i" name="post[updated_at(1i)]">\n}.dup
     expected << %{<option value="">Choose year</option>\n<option value="1999">1999</option>\n<option value="2000">2000</option>\n<option value="2001">2001</option>\n<option value="2002">2002</option>\n<option value="2003">2003</option>\n<option value="2004">2004</option>\n<option value="2005">2005</option>\n<option value="2006">2006</option>\n<option value="2007">2007</option>\n<option value="2008">2008</option>\n<option value="2009">2009</option>\n}
     expected << "</select>\n"
 
@@ -2836,14 +2860,14 @@ class DateHelperTest < ActionView::TestCase
     expected << %{<option value="">Choose minute</option>\n<option value="00">00</option>\n<option value="01">01</option>\n<option value="02">02</option>\n<option value="03">03</option>\n<option value="04">04</option>\n<option value="05">05</option>\n<option value="06">06</option>\n<option value="07">07</option>\n<option value="08">08</option>\n<option value="09">09</option>\n<option value="10">10</option>\n<option value="11">11</option>\n<option value="12">12</option>\n<option value="13">13</option>\n<option value="14">14</option>\n<option value="15">15</option>\n<option value="16">16</option>\n<option value="17">17</option>\n<option value="18">18</option>\n<option value="19">19</option>\n<option value="20">20</option>\n<option value="21">21</option>\n<option value="22">22</option>\n<option value="23">23</option>\n<option value="24">24</option>\n<option value="25">25</option>\n<option value="26">26</option>\n<option value="27">27</option>\n<option value="28">28</option>\n<option value="29">29</option>\n<option value="30">30</option>\n<option value="31">31</option>\n<option value="32">32</option>\n<option value="33">33</option>\n<option value="34">34</option>\n<option value="35">35</option>\n<option value="36">36</option>\n<option value="37">37</option>\n<option value="38">38</option>\n<option value="39">39</option>\n<option value="40">40</option>\n<option value="41">41</option>\n<option value="42">42</option>\n<option value="43">43</option>\n<option value="44">44</option>\n<option value="45">45</option>\n<option value="46">46</option>\n<option value="47">47</option>\n<option value="48">48</option>\n<option value="49">49</option>\n<option value="50">50</option>\n<option value="51">51</option>\n<option value="52">52</option>\n<option value="53">53</option>\n<option value="54">54</option>\n<option value="55">55</option>\n<option value="56">56</option>\n<option value="57">57</option>\n<option value="58">58</option>\n<option value="59">59</option>\n}
     expected << "</select>\n"
 
-    assert_dom_equal expected, datetime_select("post", "updated_at", :start_year=>1999, :end_year=>2009, :prompt => {:year => 'Choose year', :month => 'Choose month', :day => 'Choose day', :hour => 'Choose hour', :minute => 'Choose minute'})
+    assert_dom_equal expected, datetime_select("post", "updated_at", start_year: 1999, end_year: 2009, prompt: { year: "Choose year", month: "Choose month", day: "Choose day", hour: "Choose hour", minute: "Choose minute" })
   end
 
   def test_datetime_select_with_generic_with_css_classes
     @post = Post.new
     @post.written_on = Time.local(2004, 6, 15, 15, 16, 35)
 
-    expected = %{<select id="post_written_on_1i" name="post[written_on(1i)]" class="year">\n}
+    expected = %{<select id="post_written_on_1i" name="post[written_on(1i)]" class="year">\n}.dup
     expected << %{<option value="1999">1999</option>\n<option value="2000">2000</option>\n<option value="2001">2001</option>\n<option value="2002">2002</option>\n<option value="2003">2003</option>\n<option value="2004" selected="selected">2004</option>\n<option value="2005">2005</option>\n<option value="2006">2006</option>\n<option value="2007">2007</option>\n<option value="2008">2008</option>\n<option value="2009">2009</option>\n}
     expected << "</select>\n"
 
@@ -2872,7 +2896,7 @@ class DateHelperTest < ActionView::TestCase
     @post = Post.new
     @post.written_on = Time.local(2004, 6, 15, 15, 16, 35)
 
-    expected = %{<select id="post_written_on_1i" name="post[written_on(1i)]" class="my-year">\n}
+    expected = %{<select id="post_written_on_1i" name="post[written_on(1i)]" class="my-year">\n}.dup
     expected << %{<option value="1999">1999</option>\n<option value="2000">2000</option>\n<option value="2001">2001</option>\n<option value="2002">2002</option>\n<option value="2003">2003</option>\n<option value="2004" selected="selected">2004</option>\n<option value="2005">2005</option>\n<option value="2006">2006</option>\n<option value="2007">2007</option>\n<option value="2008">2008</option>\n<option value="2009">2009</option>\n}
     expected << "</select>\n"
 
@@ -2894,12 +2918,12 @@ class DateHelperTest < ActionView::TestCase
     expected << %{<option value="00">00</option>\n<option value="01">01</option>\n<option value="02">02</option>\n<option value="03">03</option>\n<option value="04">04</option>\n<option value="05">05</option>\n<option value="06">06</option>\n<option value="07">07</option>\n<option value="08">08</option>\n<option value="09">09</option>\n<option value="10">10</option>\n<option value="11">11</option>\n<option value="12">12</option>\n<option value="13">13</option>\n<option value="14">14</option>\n<option value="15">15</option>\n<option value="16" selected="selected">16</option>\n<option value="17">17</option>\n<option value="18">18</option>\n<option value="19">19</option>\n<option value="20">20</option>\n<option value="21">21</option>\n<option value="22">22</option>\n<option value="23">23</option>\n<option value="24">24</option>\n<option value="25">25</option>\n<option value="26">26</option>\n<option value="27">27</option>\n<option value="28">28</option>\n<option value="29">29</option>\n<option value="30">30</option>\n<option value="31">31</option>\n<option value="32">32</option>\n<option value="33">33</option>\n<option value="34">34</option>\n<option value="35">35</option>\n<option value="36">36</option>\n<option value="37">37</option>\n<option value="38">38</option>\n<option value="39">39</option>\n<option value="40">40</option>\n<option value="41">41</option>\n<option value="42">42</option>\n<option value="43">43</option>\n<option value="44">44</option>\n<option value="45">45</option>\n<option value="46">46</option>\n<option value="47">47</option>\n<option value="48">48</option>\n<option value="49">49</option>\n<option value="50">50</option>\n<option value="51">51</option>\n<option value="52">52</option>\n<option value="53">53</option>\n<option value="54">54</option>\n<option value="55">55</option>\n<option value="56">56</option>\n<option value="57">57</option>\n<option value="58">58</option>\n<option value="59">59</option>\n}
     expected << "</select>\n"
 
-    assert_dom_equal expected, datetime_select("post", "written_on", start_year: 1999, end_year: 2009, with_css_classes: { year: 'my-year', month: 'my-month', day: 'my-day', hour: 'my-hour', minute: 'my-minute' })
+    assert_dom_equal expected, datetime_select("post", "written_on", start_year: 1999, end_year: 2009, with_css_classes: { year: "my-year", month: "my-month", day: "my-day", hour: "my-hour", minute: "my-minute" })
   end
 
   def test_date_select_with_zero_value_and_no_start_year
-    expected =  %(<select id="date_first_year" name="date[first][year]">\n)
-    (Date.today.year-5).upto(Date.today.year+1) { |y| expected << %(<option value="#{y}">#{y}</option>\n) }
+    expected = %(<select id="date_first_year" name="date[first][year]">\n).dup
+    (Date.today.year - 5).upto(Date.today.year + 1) { |y| expected << %(<option value="#{y}">#{y}</option>\n) }
     expected << "</select>\n"
 
     expected << %(<select id="date_first_month" name="date[first][month]">\n)
@@ -2910,11 +2934,11 @@ class DateHelperTest < ActionView::TestCase
     expected << %(<option value="1">1</option>\n<option value="2">2</option>\n<option value="3">3</option>\n<option value="4">4</option>\n<option value="5">5</option>\n<option value="6">6</option>\n<option value="7">7</option>\n<option value="8">8</option>\n<option value="9">9</option>\n<option value="10">10</option>\n<option value="11">11</option>\n<option value="12">12</option>\n<option value="13">13</option>\n<option value="14">14</option>\n<option value="15">15</option>\n<option value="16">16</option>\n<option value="17">17</option>\n<option value="18">18</option>\n<option value="19">19</option>\n<option value="20">20</option>\n<option value="21">21</option>\n<option value="22">22</option>\n<option value="23">23</option>\n<option value="24">24</option>\n<option value="25">25</option>\n<option value="26">26</option>\n<option value="27">27</option>\n<option value="28">28</option>\n<option value="29">29</option>\n<option value="30">30</option>\n<option value="31">31</option>\n)
     expected << "</select>\n"
 
-    assert_dom_equal expected, select_date(0, :end_year => Date.today.year+1, :prefix => "date[first]")
+    assert_dom_equal expected, select_date(0, end_year: Date.today.year + 1, prefix: "date[first]")
   end
 
   def test_date_select_with_zero_value_and_no_end_year
-    expected =  %(<select id="date_first_year" name="date[first][year]">\n)
+    expected =  %(<select id="date_first_year" name="date[first][year]">\n).dup
     last_year = Time.now.year + 5
     2003.upto(last_year) { |y| expected << %(<option value="#{y}">#{y}</option>\n) }
     expected << "</select>\n"
@@ -2927,12 +2951,12 @@ class DateHelperTest < ActionView::TestCase
     expected << %(<option value="1">1</option>\n<option value="2">2</option>\n<option value="3">3</option>\n<option value="4">4</option>\n<option value="5">5</option>\n<option value="6">6</option>\n<option value="7">7</option>\n<option value="8">8</option>\n<option value="9">9</option>\n<option value="10">10</option>\n<option value="11">11</option>\n<option value="12">12</option>\n<option value="13">13</option>\n<option value="14">14</option>\n<option value="15">15</option>\n<option value="16">16</option>\n<option value="17">17</option>\n<option value="18">18</option>\n<option value="19">19</option>\n<option value="20">20</option>\n<option value="21">21</option>\n<option value="22">22</option>\n<option value="23">23</option>\n<option value="24">24</option>\n<option value="25">25</option>\n<option value="26">26</option>\n<option value="27">27</option>\n<option value="28">28</option>\n<option value="29">29</option>\n<option value="30">30</option>\n<option value="31">31</option>\n)
     expected << "</select>\n"
 
-    assert_dom_equal expected, select_date(0, :start_year => 2003, :prefix => "date[first]")
+    assert_dom_equal expected, select_date(0, start_year: 2003, prefix: "date[first]")
   end
 
   def test_date_select_with_zero_value_and_no_start_and_end_year
-    expected =  %(<select id="date_first_year" name="date[first][year]">\n)
-    (Date.today.year-5).upto(Date.today.year+5) { |y| expected << %(<option value="#{y}">#{y}</option>\n) }
+    expected = %(<select id="date_first_year" name="date[first][year]">\n).dup
+    (Date.today.year - 5).upto(Date.today.year + 5) { |y| expected << %(<option value="#{y}">#{y}</option>\n) }
     expected << "</select>\n"
 
     expected << %(<select id="date_first_month" name="date[first][month]">\n)
@@ -2943,12 +2967,12 @@ class DateHelperTest < ActionView::TestCase
     expected << %(<option value="1">1</option>\n<option value="2">2</option>\n<option value="3">3</option>\n<option value="4">4</option>\n<option value="5">5</option>\n<option value="6">6</option>\n<option value="7">7</option>\n<option value="8">8</option>\n<option value="9">9</option>\n<option value="10">10</option>\n<option value="11">11</option>\n<option value="12">12</option>\n<option value="13">13</option>\n<option value="14">14</option>\n<option value="15">15</option>\n<option value="16">16</option>\n<option value="17">17</option>\n<option value="18">18</option>\n<option value="19">19</option>\n<option value="20">20</option>\n<option value="21">21</option>\n<option value="22">22</option>\n<option value="23">23</option>\n<option value="24">24</option>\n<option value="25">25</option>\n<option value="26">26</option>\n<option value="27">27</option>\n<option value="28">28</option>\n<option value="29">29</option>\n<option value="30">30</option>\n<option value="31">31</option>\n)
     expected << "</select>\n"
 
-    assert_dom_equal expected, select_date(0, :prefix => "date[first]")
+    assert_dom_equal expected, select_date(0, prefix: "date[first]")
   end
 
   def test_date_select_with_nil_value_and_no_start_and_end_year
-    expected =  %(<select id="date_first_year" name="date[first][year]">\n)
-    (Date.today.year-5).upto(Date.today.year+5) { |y| expected << %(<option value="#{y}">#{y}</option>\n) }
+    expected = %(<select id="date_first_year" name="date[first][year]">\n).dup
+    (Date.today.year - 5).upto(Date.today.year + 5) { |y| expected << %(<option value="#{y}">#{y}</option>\n) }
     expected << "</select>\n"
 
     expected << %(<select id="date_first_month" name="date[first][month]">\n)
@@ -2959,12 +2983,12 @@ class DateHelperTest < ActionView::TestCase
     expected << %(<option value="1">1</option>\n<option value="2">2</option>\n<option value="3">3</option>\n<option value="4">4</option>\n<option value="5">5</option>\n<option value="6">6</option>\n<option value="7">7</option>\n<option value="8">8</option>\n<option value="9">9</option>\n<option value="10">10</option>\n<option value="11">11</option>\n<option value="12">12</option>\n<option value="13">13</option>\n<option value="14">14</option>\n<option value="15">15</option>\n<option value="16">16</option>\n<option value="17">17</option>\n<option value="18">18</option>\n<option value="19">19</option>\n<option value="20">20</option>\n<option value="21">21</option>\n<option value="22">22</option>\n<option value="23">23</option>\n<option value="24">24</option>\n<option value="25">25</option>\n<option value="26">26</option>\n<option value="27">27</option>\n<option value="28">28</option>\n<option value="29">29</option>\n<option value="30">30</option>\n<option value="31">31</option>\n)
     expected << "</select>\n"
 
-    assert_dom_equal expected, select_date(nil, :prefix => "date[first]")
+    assert_dom_equal expected, select_date(nil, prefix: "date[first]")
   end
 
   def test_datetime_select_with_nil_value_and_no_start_and_end_year
-    expected =  %(<select id="date_first_year" name="date[first][year]">\n)
-    (Date.today.year-5).upto(Date.today.year+5) { |y| expected << %(<option value="#{y}">#{y}</option>\n) }
+    expected = %(<select id="date_first_year" name="date[first][year]">\n).dup
+    (Date.today.year - 5).upto(Date.today.year + 5) { |y| expected << %(<option value="#{y}">#{y}</option>\n) }
     expected << "</select>\n"
 
     expected << %(<select id="date_first_month" name="date[first][month]">\n)
@@ -2987,7 +3011,7 @@ class DateHelperTest < ActionView::TestCase
     expected << %(<option value="00">00</option>\n<option value="01">01</option>\n<option value="02">02</option>\n<option value="03">03</option>\n<option value="04">04</option>\n<option value="05">05</option>\n<option value="06">06</option>\n<option value="07">07</option>\n<option value="08">08</option>\n<option value="09">09</option>\n<option value="10">10</option>\n<option value="11">11</option>\n<option value="12">12</option>\n<option value="13">13</option>\n<option value="14">14</option>\n<option value="15">15</option>\n<option value="16">16</option>\n<option value="17">17</option>\n<option value="18">18</option>\n<option value="19">19</option>\n<option value="20">20</option>\n<option value="21">21</option>\n<option value="22">22</option>\n<option value="23">23</option>\n<option value="24">24</option>\n<option value="25">25</option>\n<option value="26">26</option>\n<option value="27">27</option>\n<option value="28">28</option>\n<option value="29">29</option>\n<option value="30">30</option>\n<option value="31">31</option>\n<option value="32">32</option>\n<option value="33">33</option>\n<option value="34">34</option>\n<option value="35">35</option>\n<option value="36">36</option>\n<option value="37">37</option>\n<option value="38">38</option>\n<option value="39">39</option>\n<option value="40">40</option>\n<option value="41">41</option>\n<option value="42">42</option>\n<option value="43">43</option>\n<option value="44">44</option>\n<option value="45">45</option>\n<option value="46">46</option>\n<option value="47">47</option>\n<option value="48">48</option>\n<option value="49">49</option>\n<option value="50">50</option>\n<option value="51">51</option>\n<option value="52">52</option>\n<option value="53">53</option>\n<option value="54">54</option>\n<option value="55">55</option>\n<option value="56">56</option>\n<option value="57">57</option>\n<option value="58">58</option>\n<option value="59">59</option>\n)
     expected << "</select>\n"
 
-    assert_dom_equal expected, select_datetime(nil, :prefix => "date[first]")
+    assert_dom_equal expected, select_datetime(nil, prefix: "date[first]")
   end
 
   def test_datetime_select_with_options_index
@@ -2995,7 +3019,7 @@ class DateHelperTest < ActionView::TestCase
     @post.updated_at = Time.local(2004, 6, 15, 16, 35)
     id = 456
 
-    expected = %{<select id="post_456_updated_at_1i" name="post[#{id}][updated_at(1i)]">\n}
+    expected = %{<select id="post_456_updated_at_1i" name="post[#{id}][updated_at(1i)]">\n}.dup
     expected << %{<option value="1999">1999</option>\n<option value="2000">2000</option>\n<option value="2001">2001</option>\n<option value="2002">2002</option>\n<option value="2003">2003</option>\n<option value="2004" selected="selected">2004</option>\n<option value="2005">2005</option>\n<option value="2006">2006</option>\n<option value="2007">2007</option>\n<option value="2008">2008</option>\n<option value="2009">2009</option>\n}
     expected << "</select>\n"
 
@@ -3017,7 +3041,7 @@ class DateHelperTest < ActionView::TestCase
     expected << %{<option value="00">00</option>\n<option value="01">01</option>\n<option value="02">02</option>\n<option value="03">03</option>\n<option value="04">04</option>\n<option value="05">05</option>\n<option value="06">06</option>\n<option value="07">07</option>\n<option value="08">08</option>\n<option value="09">09</option>\n<option value="10">10</option>\n<option value="11">11</option>\n<option value="12">12</option>\n<option value="13">13</option>\n<option value="14">14</option>\n<option value="15">15</option>\n<option value="16">16</option>\n<option value="17">17</option>\n<option value="18">18</option>\n<option value="19">19</option>\n<option value="20">20</option>\n<option value="21">21</option>\n<option value="22">22</option>\n<option value="23">23</option>\n<option value="24">24</option>\n<option value="25">25</option>\n<option value="26">26</option>\n<option value="27">27</option>\n<option value="28">28</option>\n<option value="29">29</option>\n<option value="30">30</option>\n<option value="31">31</option>\n<option value="32">32</option>\n<option value="33">33</option>\n<option value="34">34</option>\n<option value="35" selected="selected">35</option>\n<option value="36">36</option>\n<option value="37">37</option>\n<option value="38">38</option>\n<option value="39">39</option>\n<option value="40">40</option>\n<option value="41">41</option>\n<option value="42">42</option>\n<option value="43">43</option>\n<option value="44">44</option>\n<option value="45">45</option>\n<option value="46">46</option>\n<option value="47">47</option>\n<option value="48">48</option>\n<option value="49">49</option>\n<option value="50">50</option>\n<option value="51">51</option>\n<option value="52">52</option>\n<option value="53">53</option>\n<option value="54">54</option>\n<option value="55">55</option>\n<option value="56">56</option>\n<option value="57">57</option>\n<option value="58">58</option>\n<option value="59">59</option>\n}
     expected << "</select>\n"
 
-    assert_dom_equal expected, datetime_select("post", "updated_at", :index => id)
+    assert_dom_equal expected, datetime_select("post", "updated_at", index: id)
   end
 
   def test_datetime_select_within_fields_for_with_options_index
@@ -3025,11 +3049,11 @@ class DateHelperTest < ActionView::TestCase
     @post.updated_at = Time.local(2004, 6, 15, 16, 35)
     id = 456
 
-    output_buffer = fields_for :post, @post, :index => id do |f|
+    output_buffer = fields_for :post, @post, index: id do |f|
       concat f.datetime_select(:updated_at)
     end
 
-    expected = %{<select id="post_456_updated_at_1i" name="post[#{id}][updated_at(1i)]">\n}
+    expected = %{<select id="post_456_updated_at_1i" name="post[#{id}][updated_at(1i)]">\n}.dup
     expected << %{<option value="1999">1999</option>\n<option value="2000">2000</option>\n<option value="2001">2001</option>\n<option value="2002">2002</option>\n<option value="2003">2003</option>\n<option value="2004" selected="selected">2004</option>\n<option value="2005">2005</option>\n<option value="2006">2006</option>\n<option value="2007">2007</option>\n<option value="2008">2008</option>\n<option value="2009">2009</option>\n}
     expected << "</select>\n"
 
@@ -3059,7 +3083,7 @@ class DateHelperTest < ActionView::TestCase
     @post.updated_at = Time.local(2004, 6, 15, 16, 35)
     id = @post.id
 
-    expected = %{<select id="post_123_updated_at_1i" name="post[#{id}][updated_at(1i)]">\n}
+    expected = %{<select id="post_123_updated_at_1i" name="post[#{id}][updated_at(1i)]">\n}.dup
     expected << %{<option value="1999">1999</option>\n<option value="2000">2000</option>\n<option value="2001">2001</option>\n<option value="2002">2002</option>\n<option value="2003">2003</option>\n<option value="2004" selected="selected">2004</option>\n<option value="2005">2005</option>\n<option value="2006">2006</option>\n<option value="2007">2007</option>\n<option value="2008">2008</option>\n<option value="2009">2009</option>\n}
     expected << "</select>\n"
 
@@ -3088,7 +3112,7 @@ class DateHelperTest < ActionView::TestCase
     @post = Post.new
     @post.updated_at = Time.local(2004, 6, 15, 15, 16, 35)
 
-    expected = %{<select id="post_updated_at_1i" name="post[updated_at(1i)]">\n}
+    expected = %{<select id="post_updated_at_1i" name="post[updated_at(1i)]">\n}.dup
     1999.upto(2009) { |i| expected << %(<option value="#{i}"#{' selected="selected"' if i == 2004}>#{i}</option>\n) }
     expected << "</select>\n"
     expected << %{<select id="post_updated_at_2i" name="post[updated_at(2i)]">\n}
@@ -3112,14 +3136,14 @@ class DateHelperTest < ActionView::TestCase
     0.upto(59) { |i| expected << %(<option value="#{sprintf("%02d", i)}"#{' selected="selected"' if i == 35}>#{sprintf("%02d", i)}</option>\n) }
     expected << "</select>\n"
 
-    assert_dom_equal expected, datetime_select("post", "updated_at", :include_seconds => true)
+    assert_dom_equal expected, datetime_select("post", "updated_at", include_seconds: true)
   end
 
   def test_datetime_select_discard_year
     @post = Post.new
     @post.updated_at = Time.local(2004, 6, 15, 15, 16, 35)
 
-    expected = %{<input type="hidden" id="post_updated_at_1i" name="post[updated_at(1i)]" value="2004" />\n}
+    expected = %{<input type="hidden" id="post_updated_at_1i" name="post[updated_at(1i)]" value="2004" />\n}.dup
     expected << %{<select id="post_updated_at_2i" name="post[updated_at(2i)]">\n}
     1.upto(12) { |i| expected << %(<option value="#{i}"#{' selected="selected"' if i == 6}>#{Date::MONTHNAMES[i]}</option>\n) }
     expected << "</select>\n"
@@ -3137,14 +3161,14 @@ class DateHelperTest < ActionView::TestCase
     0.upto(59) { |i| expected << %(<option value="#{sprintf("%02d", i)}"#{' selected="selected"' if i == 16}>#{sprintf("%02d", i)}</option>\n) }
     expected << "</select>\n"
 
-    assert_dom_equal expected, datetime_select("post", "updated_at", :discard_year => true)
+    assert_dom_equal expected, datetime_select("post", "updated_at", discard_year: true)
   end
 
   def test_datetime_select_discard_month
     @post = Post.new
     @post.updated_at = Time.local(2004, 6, 15, 15, 16, 35)
 
-    expected = %{<select id="post_updated_at_1i" name="post[updated_at(1i)]">\n}
+    expected = %{<select id="post_updated_at_1i" name="post[updated_at(1i)]">\n}.dup
     1999.upto(2009) { |i| expected << %(<option value="#{i}"#{' selected="selected"' if i == 2004}>#{i}</option>\n) }
     expected << "</select>\n"
     expected << %{<input type="hidden" id="post_updated_at_2i" name="post[updated_at(2i)]" value="6" />\n}
@@ -3160,14 +3184,14 @@ class DateHelperTest < ActionView::TestCase
     0.upto(59) { |i| expected << %(<option value="#{sprintf("%02d", i)}"#{' selected="selected"' if i == 16}>#{sprintf("%02d", i)}</option>\n) }
     expected << "</select>\n"
 
-    assert_dom_equal expected, datetime_select("post", "updated_at", :discard_month => true)
+    assert_dom_equal expected, datetime_select("post", "updated_at", discard_month: true)
   end
 
   def test_datetime_select_discard_year_and_month
     @post = Post.new
     @post.updated_at = Time.local(2004, 6, 15, 15, 16, 35)
 
-    expected = %{<input type="hidden" id="post_updated_at_1i" name="post[updated_at(1i)]" value="2004" />\n}
+    expected = %{<input type="hidden" id="post_updated_at_1i" name="post[updated_at(1i)]" value="2004" />\n}.dup
     expected << %{<input type="hidden" id="post_updated_at_2i" name="post[updated_at(2i)]" value="6" />\n}
     expected << %{<input type="hidden" id="post_updated_at_3i" name="post[updated_at(3i)]" value="1" />\n}
 
@@ -3179,14 +3203,14 @@ class DateHelperTest < ActionView::TestCase
     0.upto(59) { |i| expected << %(<option value="#{sprintf("%02d", i)}"#{' selected="selected"' if i == 16}>#{sprintf("%02d", i)}</option>\n) }
     expected << "</select>\n"
 
-    assert_dom_equal expected, datetime_select("post", "updated_at", :discard_year => true, :discard_month => true)
+    assert_dom_equal expected, datetime_select("post", "updated_at", discard_year: true, discard_month: true)
   end
 
   def test_datetime_select_discard_year_and_month_with_disabled_html_option
     @post = Post.new
     @post.updated_at = Time.local(2004, 6, 15, 15, 16, 35)
 
-    expected = %{<input type="hidden" id="post_updated_at_1i" disabled="disabled" name="post[updated_at(1i)]" value="2004" />\n}
+    expected = %{<input type="hidden" id="post_updated_at_1i" disabled="disabled" name="post[updated_at(1i)]" value="2004" />\n}.dup
     expected << %{<input type="hidden" id="post_updated_at_2i" disabled="disabled" name="post[updated_at(2i)]" value="6" />\n}
     expected << %{<input type="hidden" id="post_updated_at_3i" disabled="disabled" name="post[updated_at(3i)]" value="1" />\n}
 
@@ -3198,14 +3222,14 @@ class DateHelperTest < ActionView::TestCase
     0.upto(59) { |i| expected << %(<option value="#{sprintf("%02d", i)}"#{' selected="selected"' if i == 16}>#{sprintf("%02d", i)}</option>\n) }
     expected << "</select>\n"
 
-    assert_dom_equal expected, datetime_select("post", "updated_at", { :discard_year => true, :discard_month => true }, :disabled => true)
+    assert_dom_equal expected, datetime_select("post", "updated_at", { discard_year: true, discard_month: true }, { disabled: true })
   end
 
   def test_datetime_select_discard_hour
     @post = Post.new
     @post.updated_at = Time.local(2004, 6, 15, 15, 16, 35)
 
-    expected = %{<select id="post_updated_at_1i" name="post[updated_at(1i)]">\n}
+    expected = %{<select id="post_updated_at_1i" name="post[updated_at(1i)]">\n}.dup
     1999.upto(2009) { |i| expected << %(<option value="#{i}"#{' selected="selected"' if i == 2004}>#{i}</option>\n) }
     expected << "</select>\n"
     expected << %{<select id="post_updated_at_2i" name="post[updated_at(2i)]">\n}
@@ -3215,14 +3239,14 @@ class DateHelperTest < ActionView::TestCase
     1.upto(31) { |i| expected << %(<option value="#{i}"#{' selected="selected"' if i == 15}>#{i}</option>\n) }
     expected << "</select>\n"
 
-    assert_dom_equal expected, datetime_select("post", "updated_at", :discard_hour => true)
+    assert_dom_equal expected, datetime_select("post", "updated_at", discard_hour: true)
   end
 
   def test_datetime_select_discard_minute
     @post = Post.new
     @post.updated_at = Time.local(2004, 6, 15, 15, 16, 35)
 
-    expected = %{<select id="post_updated_at_1i" name="post[updated_at(1i)]">\n}
+    expected = %{<select id="post_updated_at_1i" name="post[updated_at(1i)]">\n}.dup
     1999.upto(2009) { |i| expected << %(<option value="#{i}"#{' selected="selected"' if i == 2004}>#{i}</option>\n) }
     expected << "</select>\n"
     expected << %{<select id="post_updated_at_2i" name="post[updated_at(2i)]">\n}
@@ -3239,14 +3263,14 @@ class DateHelperTest < ActionView::TestCase
     expected << "</select>\n"
     expected << %{<input type="hidden" id="post_updated_at_5i" name="post[updated_at(5i)]" value="16" />\n}
 
-    assert_dom_equal expected, datetime_select("post", "updated_at", :discard_minute => true)
+    assert_dom_equal expected, datetime_select("post", "updated_at", discard_minute: true)
   end
 
   def test_datetime_select_disabled_and_discard_minute
     @post = Post.new
     @post.updated_at = Time.local(2004, 6, 15, 15, 16, 35)
 
-    expected = %{<select id="post_updated_at_1i" disabled="disabled" name="post[updated_at(1i)]">\n}
+    expected = %{<select id="post_updated_at_1i" disabled="disabled" name="post[updated_at(1i)]">\n}.dup
     1999.upto(2009) { |i| expected << %(<option value="#{i}"#{' selected="selected"' if i == 2004}>#{i}</option>\n) }
     expected << "</select>\n"
     expected << %{<select id="post_updated_at_2i" disabled="disabled" name="post[updated_at(2i)]">\n}
@@ -3263,14 +3287,14 @@ class DateHelperTest < ActionView::TestCase
     expected << "</select>\n"
     expected << %{<input type="hidden" id="post_updated_at_5i" disabled="disabled" name="post[updated_at(5i)]" value="16" />\n}
 
-    assert_dom_equal expected, datetime_select("post", "updated_at", :discard_minute => true, :disabled => true)
+    assert_dom_equal expected, datetime_select("post", "updated_at", discard_minute: true, disabled: true)
   end
 
   def test_datetime_select_invalid_order
     @post = Post.new
     @post.updated_at = Time.local(2004, 6, 15, 15, 16, 35)
 
-    expected = %{<select id="post_updated_at_3i" name="post[updated_at(3i)]">\n}
+    expected = %{<select id="post_updated_at_3i" name="post[updated_at(3i)]">\n}.dup
     1.upto(31) { |i| expected << %(<option value="#{i}"#{' selected="selected"' if i == 15}>#{i}</option>\n) }
     expected << "</select>\n"
     expected << %{<select id="post_updated_at_2i" name="post[updated_at(2i)]">\n}
@@ -3290,14 +3314,14 @@ class DateHelperTest < ActionView::TestCase
     0.upto(59) { |i| expected << %(<option value="#{sprintf("%02d", i)}"#{' selected="selected"' if i == 16}>#{sprintf("%02d", i)}</option>\n) }
     expected << "</select>\n"
 
-    assert_dom_equal expected, datetime_select("post", "updated_at", :order => [:minute, :day, :hour, :month, :year, :second])
+    assert_dom_equal expected, datetime_select("post", "updated_at", order: [:minute, :day, :hour, :month, :year, :second])
   end
 
   def test_datetime_select_discard_with_order
     @post = Post.new
     @post.updated_at = Time.local(2004, 6, 15, 15, 16, 35)
 
-    expected = %{<input type="hidden" id="post_updated_at_1i" name="post[updated_at(1i)]" value="2004" />\n}
+    expected = %{<input type="hidden" id="post_updated_at_1i" name="post[updated_at(1i)]" value="2004" />\n}.dup
     expected << %{<select id="post_updated_at_3i" name="post[updated_at(3i)]">\n}
     1.upto(31) { |i| expected << %(<option value="#{i}"#{' selected="selected"' if i == 15}>#{i}</option>\n) }
     expected << "</select>\n"
@@ -3315,14 +3339,14 @@ class DateHelperTest < ActionView::TestCase
     0.upto(59) { |i| expected << %(<option value="#{sprintf("%02d", i)}"#{' selected="selected"' if i == 16}>#{sprintf("%02d", i)}</option>\n) }
     expected << "</select>\n"
 
-    assert_dom_equal expected, datetime_select("post", "updated_at", :order => [:day, :month])
+    assert_dom_equal expected, datetime_select("post", "updated_at", order: [:day, :month])
   end
 
   def test_datetime_select_with_default_value_as_time
     @post = Post.new
     @post.updated_at = nil
 
-    expected = %{<select id="post_updated_at_1i" name="post[updated_at(1i)]">\n}
+    expected = %{<select id="post_updated_at_1i" name="post[updated_at(1i)]">\n}.dup
     2001.upto(2011) { |i| expected << %(<option value="#{i}"#{' selected="selected"' if i == 2006}>#{i}</option>\n) }
     expected << "</select>\n"
     expected << %{<select id="post_updated_at_2i" name="post[updated_at(2i)]">\n}
@@ -3342,14 +3366,14 @@ class DateHelperTest < ActionView::TestCase
     0.upto(59) { |i| expected << %(<option value="#{sprintf("%02d", i)}"#{' selected="selected"' if i == 16}>#{sprintf("%02d", i)}</option>\n) }
     expected << "</select>\n"
 
-    assert_dom_equal expected, datetime_select("post", "updated_at", :default => Time.local(2006, 9, 19, 15, 16, 35))
+    assert_dom_equal expected, datetime_select("post", "updated_at", default: Time.local(2006, 9, 19, 15, 16, 35))
   end
 
   def test_include_blank_overrides_default_option
     @post = Post.new
     @post.updated_at = nil
 
-    expected = %{<select id="post_updated_at_1i" name="post[updated_at(1i)]">\n}
+    expected = %{<select id="post_updated_at_1i" name="post[updated_at(1i)]">\n}.dup
     expected << %(<option value=""></option>\n)
     (Time.now.year - 5).upto(Time.now.year + 5) { |i| expected << %(<option value="#{i}">#{i}</option>\n) }
     expected << "</select>\n"
@@ -3362,14 +3386,14 @@ class DateHelperTest < ActionView::TestCase
     1.upto(31) { |i| expected << %(<option value="#{i}">#{i}</option>\n) }
     expected << "</select>\n"
 
-    assert_dom_equal expected, date_select("post", "updated_at", :default => Time.local(2006, 9, 19, 15, 16, 35), :include_blank => true)
+    assert_dom_equal expected, date_select("post", "updated_at", default: Time.local(2006, 9, 19, 15, 16, 35), include_blank: true)
   end
 
   def test_datetime_select_with_default_value_as_hash
     @post = Post.new
     @post.updated_at = nil
 
-    expected = %{<select id="post_updated_at_1i" name="post[updated_at(1i)]">\n}
+    expected = %{<select id="post_updated_at_1i" name="post[updated_at(1i)]">\n}.dup
     (Time.now.year - 5).upto(Time.now.year + 5) { |i| expected << %(<option value="#{i}"#{' selected="selected"' if i == Time.now.year}>#{i}</option>\n) }
     expected << "</select>\n"
     expected << %{<select id="post_updated_at_2i" name="post[updated_at(2i)]">\n}
@@ -3389,14 +3413,14 @@ class DateHelperTest < ActionView::TestCase
     0.upto(59) { |i| expected << %(<option value="#{sprintf("%02d", i)}"#{' selected="selected"' if i == 42}>#{sprintf("%02d", i)}</option>\n) }
     expected << "</select>\n"
 
-    assert_dom_equal expected, datetime_select("post", "updated_at", :default => { :month => 10, :minute => 42, :hour => 9 })
+    assert_dom_equal expected, datetime_select("post", "updated_at", default: { month: 10, minute: 42, hour: 9 })
   end
 
   def test_datetime_select_with_html_options
     @post = Post.new
     @post.updated_at = Time.local(2004, 6, 15, 16, 35)
 
-    expected = %{<select id="post_updated_at_1i" name="post[updated_at(1i)]" class="selector">\n}
+    expected = %{<select id="post_updated_at_1i" name="post[updated_at(1i)]" class="selector">\n}.dup
     expected << %{<option value="1999">1999</option>\n<option value="2000">2000</option>\n<option value="2001">2001</option>\n<option value="2002">2002</option>\n<option value="2003">2003</option>\n<option value="2004" selected="selected">2004</option>\n<option value="2005">2005</option>\n<option value="2006">2006</option>\n<option value="2007">2007</option>\n<option value="2008">2008</option>\n<option value="2009">2009</option>\n}
     expected << "</select>\n"
 
@@ -3418,7 +3442,7 @@ class DateHelperTest < ActionView::TestCase
     expected << %{<option value="00">00</option>\n<option value="01">01</option>\n<option value="02">02</option>\n<option value="03">03</option>\n<option value="04">04</option>\n<option value="05">05</option>\n<option value="06">06</option>\n<option value="07">07</option>\n<option value="08">08</option>\n<option value="09">09</option>\n<option value="10">10</option>\n<option value="11">11</option>\n<option value="12">12</option>\n<option value="13">13</option>\n<option value="14">14</option>\n<option value="15">15</option>\n<option value="16">16</option>\n<option value="17">17</option>\n<option value="18">18</option>\n<option value="19">19</option>\n<option value="20">20</option>\n<option value="21">21</option>\n<option value="22">22</option>\n<option value="23">23</option>\n<option value="24">24</option>\n<option value="25">25</option>\n<option value="26">26</option>\n<option value="27">27</option>\n<option value="28">28</option>\n<option value="29">29</option>\n<option value="30">30</option>\n<option value="31">31</option>\n<option value="32">32</option>\n<option value="33">33</option>\n<option value="34">34</option>\n<option value="35" selected="selected">35</option>\n<option value="36">36</option>\n<option value="37">37</option>\n<option value="38">38</option>\n<option value="39">39</option>\n<option value="40">40</option>\n<option value="41">41</option>\n<option value="42">42</option>\n<option value="43">43</option>\n<option value="44">44</option>\n<option value="45">45</option>\n<option value="46">46</option>\n<option value="47">47</option>\n<option value="48">48</option>\n<option value="49">49</option>\n<option value="50">50</option>\n<option value="51">51</option>\n<option value="52">52</option>\n<option value="53">53</option>\n<option value="54">54</option>\n<option value="55">55</option>\n<option value="56">56</option>\n<option value="57">57</option>\n<option value="58">58</option>\n<option value="59">59</option>\n}
     expected << "</select>\n"
 
-    assert_dom_equal expected, datetime_select("post", "updated_at", {}, :class => 'selector')
+    assert_dom_equal expected, datetime_select("post", "updated_at", {}, { class: "selector" })
   end
 
   def test_date_select_should_not_change_passed_options_hash
@@ -3426,24 +3450,24 @@ class DateHelperTest < ActionView::TestCase
     @post.updated_at = Time.local(2008, 7, 16, 23, 30)
 
     options = {
-      :order => [ :year, :month, :day ],
-      :default => { :year => 2008, :month => 7, :day => 16, :hour => 23, :minute => 30, :second => 1 },
-      :discard_type => false,
-      :include_blank => false,
-      :ignore_date => false,
-      :include_seconds => true
+      order: [ :year, :month, :day ],
+      default: { year: 2008, month: 7, day: 16, hour: 23, minute: 30, second: 1 },
+      discard_type: false,
+      include_blank: false,
+      ignore_date: false,
+      include_seconds: true
     }
     date_select(@post, :updated_at, options)
 
     # note: the literal hash is intentional to show that the actual options hash isn't modified
     #       don't change this!
     assert_equal({
-      :order => [ :year, :month, :day ],
-      :default => { :year => 2008, :month => 7, :day => 16, :hour => 23, :minute => 30, :second => 1 },
-      :discard_type => false,
-      :include_blank => false,
-      :ignore_date => false,
-      :include_seconds => true
+      order: [ :year, :month, :day ],
+      default: { year: 2008, month: 7, day: 16, hour: 23, minute: 30, second: 1 },
+      discard_type: false,
+      include_blank: false,
+      ignore_date: false,
+      include_seconds: true
     }, options)
   end
 
@@ -3452,24 +3476,24 @@ class DateHelperTest < ActionView::TestCase
     @post.updated_at = Time.local(2008, 7, 16, 23, 30)
 
     options = {
-      :order => [ :year, :month, :day ],
-      :default => { :year => 2008, :month => 7, :day => 16, :hour => 23, :minute => 30, :second => 1 },
-      :discard_type => false,
-      :include_blank => false,
-      :ignore_date => false,
-      :include_seconds => true
+      order: [ :year, :month, :day ],
+      default: { year: 2008, month: 7, day: 16, hour: 23, minute: 30, second: 1 },
+      discard_type: false,
+      include_blank: false,
+      ignore_date: false,
+      include_seconds: true
     }
     datetime_select(@post, :updated_at, options)
 
     # note: the literal hash is intentional to show that the actual options hash isn't modified
     #       don't change this!
     assert_equal({
-      :order => [ :year, :month, :day ],
-      :default => { :year => 2008, :month => 7, :day => 16, :hour => 23, :minute => 30, :second => 1 },
-      :discard_type => false,
-      :include_blank => false,
-      :ignore_date => false,
-      :include_seconds => true
+      order: [ :year, :month, :day ],
+      default: { year: 2008, month: 7, day: 16, hour: 23, minute: 30, second: 1 },
+      discard_type: false,
+      include_blank: false,
+      ignore_date: false,
+      include_seconds: true
     }, options)
   end
 
@@ -3478,93 +3502,93 @@ class DateHelperTest < ActionView::TestCase
     @post.updated_at = Time.local(2008, 7, 16, 23, 30)
 
     options = {
-      :order => [ :year, :month, :day ],
-      :default => { :year => 2008, :month => 7, :day => 16, :hour => 23, :minute => 30, :second => 1 },
-      :discard_type => false,
-      :include_blank => false,
-      :ignore_date => false,
-      :include_seconds => true
+      order: [ :year, :month, :day ],
+      default: { year: 2008, month: 7, day: 16, hour: 23, minute: 30, second: 1 },
+      discard_type: false,
+      include_blank: false,
+      ignore_date: false,
+      include_seconds: true
     }
     time_select(@post, :updated_at, options)
 
     # note: the literal hash is intentional to show that the actual options hash isn't modified
     #       don't change this!
     assert_equal({
-      :order => [ :year, :month, :day ],
-      :default => { :year => 2008, :month => 7, :day => 16, :hour => 23, :minute => 30, :second => 1 },
-      :discard_type => false,
-      :include_blank => false,
-      :ignore_date => false,
-      :include_seconds => true
+      order: [ :year, :month, :day ],
+      default: { year: 2008, month: 7, day: 16, hour: 23, minute: 30, second: 1 },
+      discard_type: false,
+      include_blank: false,
+      ignore_date: false,
+      include_seconds: true
     }, options)
   end
 
   def test_select_date_should_not_change_passed_options_hash
     options = {
-      :order => [ :year, :month, :day ],
-      :default => { :year => 2008, :month => 7, :day => 16, :hour => 23, :minute => 30, :second => 1 },
-      :discard_type => false,
-      :include_blank => false,
-      :ignore_date => false,
-      :include_seconds => true
+      order: [ :year, :month, :day ],
+      default: { year: 2008, month: 7, day: 16, hour: 23, minute: 30, second: 1 },
+      discard_type: false,
+      include_blank: false,
+      ignore_date: false,
+      include_seconds: true
     }
     select_date(Date.today, options)
 
     # note: the literal hash is intentional to show that the actual options hash isn't modified
     #       don't change this!
     assert_equal({
-      :order => [ :year, :month, :day ],
-      :default => { :year => 2008, :month => 7, :day => 16, :hour => 23, :minute => 30, :second => 1 },
-      :discard_type => false,
-      :include_blank => false,
-      :ignore_date => false,
-      :include_seconds => true
+      order: [ :year, :month, :day ],
+      default: { year: 2008, month: 7, day: 16, hour: 23, minute: 30, second: 1 },
+      discard_type: false,
+      include_blank: false,
+      ignore_date: false,
+      include_seconds: true
     }, options)
   end
 
   def test_select_datetime_should_not_change_passed_options_hash
     options = {
-      :order => [ :year, :month, :day ],
-      :default => { :year => 2008, :month => 7, :day => 16, :hour => 23, :minute => 30, :second => 1 },
-      :discard_type => false,
-      :include_blank => false,
-      :ignore_date => false,
-      :include_seconds => true
+      order: [ :year, :month, :day ],
+      default: { year: 2008, month: 7, day: 16, hour: 23, minute: 30, second: 1 },
+      discard_type: false,
+      include_blank: false,
+      ignore_date: false,
+      include_seconds: true
     }
     select_datetime(Time.now, options)
 
     # note: the literal hash is intentional to show that the actual options hash isn't modified
     #       don't change this!
     assert_equal({
-      :order => [ :year, :month, :day ],
-      :default => { :year => 2008, :month => 7, :day => 16, :hour => 23, :minute => 30, :second => 1 },
-      :discard_type => false,
-      :include_blank => false,
-      :ignore_date => false,
-      :include_seconds => true
+      order: [ :year, :month, :day ],
+      default: { year: 2008, month: 7, day: 16, hour: 23, minute: 30, second: 1 },
+      discard_type: false,
+      include_blank: false,
+      ignore_date: false,
+      include_seconds: true
     }, options)
   end
 
   def test_select_time_should_not_change_passed_options_hash
     options = {
-      :order => [ :year, :month, :day ],
-      :default => { :year => 2008, :month => 7, :day => 16, :hour => 23, :minute => 30, :second => 1 },
-      :discard_type => false,
-      :include_blank => false,
-      :ignore_date => false,
-      :include_seconds => true
+      order: [ :year, :month, :day ],
+      default: { year: 2008, month: 7, day: 16, hour: 23, minute: 30, second: 1 },
+      discard_type: false,
+      include_blank: false,
+      ignore_date: false,
+      include_seconds: true
     }
     select_time(Time.now, options)
 
     # note: the literal hash is intentional to show that the actual options hash isn't modified
     #       don't change this!
     assert_equal({
-      :order => [ :year, :month, :day ],
-      :default => { :year => 2008, :month => 7, :day => 16, :hour => 23, :minute => 30, :second => 1 },
-      :discard_type => false,
-      :include_blank => false,
-      :ignore_date => false,
-      :include_seconds => true
+      order: [ :year, :month, :day ],
+      default: { year: 2008, month: 7, day: 16, hour: 23, minute: 30, second: 1 },
+      discard_type: false,
+      include_blank: false,
+      ignore_date: false,
+      include_seconds: true
     }, options)
   end
 
@@ -3575,19 +3599,19 @@ class DateHelperTest < ActionView::TestCase
     assert select_minute(Time.mktime(2003, 8, 16, 8, 4, 18)).html_safe?
     assert select_second(Time.mktime(2003, 8, 16, 8, 4, 18)).html_safe?
 
-    assert select_minute(8, :use_hidden => true).html_safe?
-    assert select_month(8, :prompt => 'Choose month').html_safe?
+    assert select_minute(8, use_hidden: true).html_safe?
+    assert select_month(8, prompt: "Choose month").html_safe?
 
-    assert select_time(Time.mktime(2003, 8, 16, 8, 4, 18), {}, :class => 'selector').html_safe?
-    assert select_date(Time.mktime(2003, 8, 16), :date_separator => " / ", :start_year => 2003, :end_year => 2005, :prefix => "date[first]").html_safe?
+    assert select_time(Time.mktime(2003, 8, 16, 8, 4, 18), {}, { class: "selector" }).html_safe?
+    assert select_date(Time.mktime(2003, 8, 16), date_separator: " / ", start_year: 2003, end_year: 2005, prefix: "date[first]").html_safe?
   end
 
   def test_object_select_html_safety
     @post = Post.new
     @post.written_on = Date.new(2004, 6, 15)
 
-    assert date_select("post", "written_on", :default => Time.local(2006, 9, 19, 15, 16, 35), :include_blank => true).html_safe?
-    assert time_select("post", "written_on", :ignore_date => true).html_safe?
+    assert date_select("post", "written_on", default: Time.local(2006, 9, 19, 15, 16, 35), include_blank: true).html_safe?
+    assert time_select("post", "written_on", ignore_date: true).html_safe?
   end
 
   def test_time_tag_with_date
@@ -3597,26 +3621,22 @@ class DateHelperTest < ActionView::TestCase
   end
 
   def test_time_tag_with_time
-    time = Time.new(2013, 2, 20, 0, 0, 0, '+00:00')
+    time = Time.new(2013, 2, 20, 0, 0, 0, "+00:00")
     expected = '<time datetime="2013-02-20T00:00:00+00:00">February 20, 2013 00:00</time>'
     assert_equal expected, time_tag(time)
   end
 
-  def test_time_tag_pubdate_option
-    assert_match(/<time.*pubdate="pubdate">.*<\/time>/, time_tag(Time.now, :pubdate => true))
-  end
-
   def test_time_tag_with_given_text
-    assert_match(/<time.*>Right now<\/time>/, time_tag(Time.now, 'Right now'))
+    assert_match(/<time.*>Right now<\/time>/, time_tag(Time.now, "Right now"))
   end
 
   def test_time_tag_with_given_block
-    assert_match(/<time.*><span>Right now<\/span><\/time>/, time_tag(Time.now){ raw('<span>Right now</span>') })
+    assert_match(/<time.*><span>Right now<\/span><\/time>/, time_tag(Time.now) { raw("<span>Right now</span>") })
   end
 
   def test_time_tag_with_different_format
-    time = Time.new(2013, 2, 20, 0, 0, 0, '+00:00')
+    time = Time.new(2013, 2, 20, 0, 0, 0, "+00:00")
     expected = '<time datetime="2013-02-20T00:00:00+00:00">20 Feb 00:00</time>'
-    assert_equal expected, time_tag(time, :format => :short)
+    assert_equal expected, time_tag(time, format: :short)
   end
 end
diff --git a/actionview/test/template/dependency_tracker_test.rb b/actionview/test/template/dependency_tracker_test.rb
index 3ece9e50cd..ef7aeac039 100644
--- a/actionview/test/template/dependency_tracker_test.rb
+++ b/actionview/test/template/dependency_tracker_test.rb
@@ -1,5 +1,7 @@
-require 'abstract_unit'
-require 'action_view/dependency_tracker'
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "action_view/dependency_tracker"
 
 class NeckbeardTracker
   def self.call(name, template)
@@ -15,8 +17,8 @@ class FakeTemplate
   end
 end
 
-Neckbeard = lambda {|template| template.source }
-Bowtie = lambda {|template| template.source }
+Neckbeard = lambda { |template| template.source }
+Bowtie = lambda { |template| template.source }
 
 class DependencyTrackerTest < ActionView::TestCase
   def tracker
diff --git a/actionview/test/template/digestor_test.rb b/actionview/test/template/digestor_test.rb
index 410f562f07..1bfa39a319 100644
--- a/actionview/test/template/digestor_test.rb
+++ b/actionview/test/template/digestor_test.rb
@@ -1,23 +1,14 @@
-require 'abstract_unit'
-require 'fileutils'
-require 'action_view/dependency_tracker'
+# frozen_string_literal: true
 
-class FixtureTemplate
-  attr_reader :source, :handler
-
-  def initialize(template_path)
-    @source = File.read(template_path)
-    @handler = ActionView::Template.handler_for_extension(:erb)
-  rescue Errno::ENOENT
-    raise ActionView::MissingTemplate.new([], "", [], true, [])
-  end
-end
+require "abstract_unit"
+require "fileutils"
+require "action_view/dependency_tracker"
 
 class FixtureFinder < ActionView::LookupContext
-  FIXTURES_DIR = "#{File.dirname(__FILE__)}/../fixtures/digestor"
+  FIXTURES_DIR = File.expand_path("../fixtures/digestor", __dir__)
 
   def initialize(details = {})
-    super(ActionView::PathSet.new(['digestor', 'digestor/api']), details, [])
+    super(ActionView::PathSet.new(["digestor", "digestor/api"]), details, [])
     @rendered_format = :html
   end
 end
@@ -122,25 +113,25 @@ class TemplateDigestorTest < ActionView::TestCase
   end
 
   def test_logging_of_missing_template_for_dependencies
-    assert_logged "'messages/something_missing' file doesn't exist, so no dependencies" do
+    assert_logged "Couldn't find template for digesting: messages/something_missing" do
       dependencies("messages/something_missing")
     end
   end
 
   def test_logging_of_missing_template_for_nested_dependencies
-    assert_logged "'messages/something_missing' file doesn't exist, so no dependencies" do
+    assert_logged "Couldn't find template for digesting: messages/something_missing" do
       nested_dependencies("messages/something_missing")
     end
   end
 
   def test_getting_of_singly_nested_dependencies
     singly_nested_dependencies = ["messages/header", "messages/form", "messages/message", "events/event", "comments/comment"]
-    assert_equal singly_nested_dependencies, nested_dependencies('messages/edit')
+    assert_equal singly_nested_dependencies, nested_dependencies("messages/edit")
   end
 
   def test_getting_of_doubly_nested_dependencies
-    doubly_nested = [{"comments/comments"=>["comments/comment"]}, "messages/message"]
-    assert_equal doubly_nested, nested_dependencies('messages/peek')
+    doubly_nested = [{ "comments/comments" => ["comments/comment"] }, "messages/message"]
+    assert_equal doubly_nested, nested_dependencies("messages/peek")
   end
 
   def test_nested_template_directory
@@ -150,13 +141,13 @@ class TemplateDigestorTest < ActionView::TestCase
   end
 
   def test_nested_template_deps
-    nested_deps = ["messages/header", {"comments/comments"=>["comments/comment"]}, "messages/actions/move", "events/event", "messages/something_missing", "messages/something_missing_1", "messages/message", "messages/form"]
+    nested_deps = ["messages/header", { "comments/comments" => ["comments/comment"] }, "messages/actions/move", "events/event", "messages/something_missing", "messages/something_missing_1", "messages/message", "messages/form"]
     assert_equal nested_deps, nested_dependencies("messages/show")
   end
 
   def test_nested_template_deps_with_non_default_rendered_format
     finder.rendered_format = nil
-    nested_deps = [{"comments/comments"=>["comments/comment"]}]
+    nested_deps = [{ "comments/comments" => ["comments/comment"] }]
     assert_equal nested_deps, nested_dependencies("messages/thread")
   end
 
@@ -195,7 +186,7 @@ class TemplateDigestorTest < ActionView::TestCase
   end
 
   def test_dont_generate_a_digest_for_missing_templates
-    assert_equal '', digest("nothing/there")
+    assert_equal "", digest("nothing/there")
   end
 
   def test_collection_dependency
@@ -216,7 +207,7 @@ class TemplateDigestorTest < ActionView::TestCase
 
   def test_details_are_included_in_cache_key
     # Cache the template digest.
-    @finder = FixtureFinder.new({:formats => [:html]})
+    @finder = FixtureFinder.new(formats: [:html])
     old_digest = digest("events/_event")
 
     # Change the template; the cached digest remains unchanged.
diff --git a/actionview/test/template/erb/form_for_test.rb b/actionview/test/template/erb/form_for_test.rb
index e722b40a9a..b6ecf003a5 100644
--- a/actionview/test/template/erb/form_for_test.rb
+++ b/actionview/test/template/erb/form_for_test.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require "abstract_unit"
 require "template/erb/helper"
 
diff --git a/actionview/test/template/erb/helper.rb b/actionview/test/template/erb/helper.rb
index a1973068d5..57d6cb1be3 100644
--- a/actionview/test/template/erb/helper.rb
+++ b/actionview/test/template/erb/helper.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ERBTest
   class ViewContext
     include ActionView::Helpers::UrlHelper
@@ -14,7 +16,7 @@ module ERBTest
   class BlockTestCase < ActiveSupport::TestCase
     def render_content(start, inside)
       template = block_helper(start, inside)
-      ActionView::Template::Handlers::Erubis.new(template).evaluate(ViewContext.new)
+      ActionView::Template::Handlers::ERB.erb_implementation.new(template).evaluate(ViewContext.new)
     end
 
     def block_helper(str, rest)
diff --git a/actionview/test/template/erb/tag_helper_test.rb b/actionview/test/template/erb/tag_helper_test.rb
index 84e328d8be..24a7592950 100644
--- a/actionview/test/template/erb/tag_helper_test.rb
+++ b/actionview/test/template/erb/tag_helper_test.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require "abstract_unit"
 require "template/erb/helper"
 
@@ -18,8 +20,8 @@ module ERBTest
     end
 
     test "percent equals works with form tags" do
-      expected_output = %r{<form.*action="foo".*method="post">.*hello*</form>}
-      assert_match expected_output, render_content("form_tag('foo')", "<%= 'hello' %>")
+      expected_output = %r{<form.*action="/foo".*method="post">.*hello*</form>}
+      assert_match expected_output, render_content("form_tag('/foo')", "<%= 'hello' %>")
     end
 
     test "percent equals works with fieldset tags" do
diff --git a/actionview/test/template/erb_util_test.rb b/actionview/test/template/erb_util_test.rb
index 3e72be31de..8b804105f4 100644
--- a/actionview/test/template/erb_util_test.rb
+++ b/actionview/test/template/erb_util_test.rb
@@ -1,5 +1,7 @@
-require 'abstract_unit'
-require 'active_support/json'
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "active_support/json"
 
 class ErbUtilTest < ActiveSupport::TestCase
   include ERB::Util
@@ -17,19 +19,19 @@ class ErbUtilTest < ActiveSupport::TestCase
   end
 
   HTML_ESCAPE_TEST_CASES = [
-    ['<br>', '&lt;br&gt;'],
-    ['a & b', 'a &amp; b'],
-    ['"quoted" string', '&quot;quoted&quot; string'],
-    ["'quoted' string", '&#39;quoted&#39; string'],
+    ["<br>", "&lt;br&gt;"],
+    ["a & b", "a &amp; b"],
+    ['"quoted" string', "&quot;quoted&quot; string"],
+    ["'quoted' string", "&#39;quoted&#39; string"],
     [
       '<script type="application/javascript">alert("You are \'pwned\'!")</script>',
-      '&lt;script type=&quot;application/javascript&quot;&gt;alert(&quot;You are &#39;pwned&#39;!&quot;)&lt;/script&gt;'
+      "&lt;script type=&quot;application/javascript&quot;&gt;alert(&quot;You are &#39;pwned&#39;!&quot;)&lt;/script&gt;"
     ]
   ]
 
   JSON_ESCAPE_TEST_CASES = [
-    ['1', '1'],
-    ['null', 'null'],
+    ["1", "1"],
+    ["null", "null"],
     ['"&"', '"\u0026"'],
     ['"</script>"', '"\u003c/script\u003e"'],
     ['["</script>"]', '["\u003c/script\u003e"]'],
@@ -51,7 +53,12 @@ class ErbUtilTest < ActiveSupport::TestCase
 
   def test_json_escape_does_not_alter_json_string_meaning
     JSON_ESCAPE_TEST_CASES.each do |(raw, _)|
-      assert_equal ActiveSupport::JSON.decode(raw), ActiveSupport::JSON.decode(json_escape(raw))
+      expected = ActiveSupport::JSON.decode(raw)
+      if expected.nil?
+        assert_nil ActiveSupport::JSON.decode(json_escape(raw))
+      else
+        assert_equal expected, ActiveSupport::JSON.decode(json_escape(raw))
+      end
     end
   end
 
@@ -91,17 +98,17 @@ class ErbUtilTest < ActiveSupport::TestCase
   end
 
   def test_html_escape_once
-    assert_equal '1 &lt;&gt;&amp;&quot;&#39; 2 &amp; 3', html_escape_once('1 <>&"\' 2 &amp; 3')
+    assert_equal "1 &lt;&gt;&amp;&quot;&#39; 2 &amp; 3", html_escape_once('1 <>&"\' 2 &amp; 3')
     assert_equal " &#X27; &#x27; &#x03BB; &#X03bb; &quot; &#39; &lt; &gt; ", html_escape_once(" &#X27; &#x27; &#x03BB; &#X03bb; \" ' < > ")
   end
 
   def test_html_escape_once_returns_unsafe_strings_when_passed_unsafe_strings
-    value = html_escape_once('1 < 2 &amp; 3')
+    value = html_escape_once("1 < 2 &amp; 3")
     assert !value.html_safe?
   end
 
   def test_html_escape_once_returns_safe_strings_when_passed_safe_strings
-    value = html_escape_once('1 < 2 &amp; 3'.html_safe)
+    value = html_escape_once("1 < 2 &amp; 3".html_safe)
     assert value.html_safe?
   end
 end
diff --git a/actionview/test/template/form_collections_helper_test.rb b/actionview/test/template/form_collections_helper_test.rb
index 4f7ea88169..6db55a1447 100644
--- a/actionview/test/template/form_collections_helper_test.rb
+++ b/actionview/test/template/form_collections_helper_test.rb
@@ -1,11 +1,12 @@
-require 'abstract_unit'
+# frozen_string_literal: true
 
-class Category < Struct.new(:id, :name)
-end
+require "abstract_unit"
+
+Category = Struct.new(:id, :name)
 
 class FormCollectionsHelperTest < ActionView::TestCase
   def assert_no_select(selector, value = nil)
-    assert_select(selector, :text => value, :count => 0)
+    assert_select(selector, text: value, count: 0)
   end
 
   def with_collection_radio_buttons(*args, &block)
@@ -17,170 +18,177 @@ class FormCollectionsHelperTest < ActionView::TestCase
   end
 
   # COLLECTION RADIO BUTTONS
-  test 'collection radio accepts a collection and generates inputs from value method' do
+  test "collection radio accepts a collection and generates inputs from value method" do
     with_collection_radio_buttons :user, :active, [true, false], :to_s, :to_s
 
-    assert_select 'input[type=radio][value=true]#user_active_true'
-    assert_select 'input[type=radio][value=false]#user_active_false'
+    assert_select "input[type=radio][value=true]#user_active_true"
+    assert_select "input[type=radio][value=false]#user_active_false"
   end
 
-  test 'collection radio accepts a collection and generates inputs from label method' do
+  test "collection radio accepts a collection and generates inputs from label method" do
     with_collection_radio_buttons :user, :active, [true, false], :to_s, :to_s
 
-    assert_select 'label[for=user_active_true]', 'true'
-    assert_select 'label[for=user_active_false]', 'false'
+    assert_select "label[for=user_active_true]", "true"
+    assert_select "label[for=user_active_false]", "false"
+  end
+
+  test "collection radio handles camelized collection values for labels correctly" do
+    with_collection_radio_buttons :user, :active, ["Yes", "No"], :to_s, :to_s
+
+    assert_select "label[for=user_active_yes]", "Yes"
+    assert_select "label[for=user_active_no]", "No"
   end
 
-  test 'collection radio handles camelized collection values for labels correctly' do
-    with_collection_radio_buttons :user, :active, ['Yes', 'No'], :to_s, :to_s
+  test "collection radio generates labels for non-English values correctly" do
+    with_collection_radio_buttons :user, :title, ["Господин", "Госпожа"], :to_s, :to_s
 
-    assert_select 'label[for=user_active_yes]', 'Yes'
-    assert_select 'label[for=user_active_no]', 'No'
+    assert_select "input[type=radio]#user_title_господин"
+    assert_select "label[for=user_title_господин]", "Господин"
   end
 
-  test 'collection radio should sanitize collection values for labels correctly' do
-    with_collection_radio_buttons :user, :name, ['$0.99', '$1.99'], :to_s, :to_s
-    assert_select 'label[for=user_name_099]', '$0.99'
-    assert_select 'label[for=user_name_199]', '$1.99'
+  test "collection radio should sanitize collection values for labels correctly" do
+    with_collection_radio_buttons :user, :name, ["$0.99", "$1.99"], :to_s, :to_s
+    assert_select "label[for=user_name_099]", "$0.99"
+    assert_select "label[for=user_name_199]", "$1.99"
   end
 
-  test 'collection radio accepts checked item' do
-    with_collection_radio_buttons :user, :active, [[1, true], [0, false]], :last, :first, :checked => true
+  test "collection radio accepts checked item" do
+    with_collection_radio_buttons :user, :active, [[1, true], [0, false]], :last, :first, checked: true
 
-    assert_select 'input[type=radio][value=true][checked=checked]'
-    assert_no_select 'input[type=radio][value=false][checked=checked]'
+    assert_select "input[type=radio][value=true][checked=checked]"
+    assert_no_select "input[type=radio][value=false][checked=checked]"
   end
 
-  test 'collection radio accepts multiple disabled items' do
-    collection = [[1, true], [0, false], [2, 'other']]
-    with_collection_radio_buttons :user, :active, collection, :last, :first, :disabled => [true, false]
+  test "collection radio accepts multiple disabled items" do
+    collection = [[1, true], [0, false], [2, "other"]]
+    with_collection_radio_buttons :user, :active, collection, :last, :first, disabled: [true, false]
 
-    assert_select 'input[type=radio][value=true][disabled=disabled]'
-    assert_select 'input[type=radio][value=false][disabled=disabled]'
-    assert_no_select 'input[type=radio][value=other][disabled=disabled]'
+    assert_select "input[type=radio][value=true][disabled=disabled]"
+    assert_select "input[type=radio][value=false][disabled=disabled]"
+    assert_no_select "input[type=radio][value=other][disabled=disabled]"
   end
 
-  test 'collection radio accepts single disabled item' do
+  test "collection radio accepts single disabled item" do
     collection = [[1, true], [0, false]]
-    with_collection_radio_buttons :user, :active, collection, :last, :first, :disabled => true
+    with_collection_radio_buttons :user, :active, collection, :last, :first, disabled: true
 
-    assert_select 'input[type=radio][value=true][disabled=disabled]'
-    assert_no_select 'input[type=radio][value=false][disabled=disabled]'
+    assert_select "input[type=radio][value=true][disabled=disabled]"
+    assert_no_select "input[type=radio][value=false][disabled=disabled]"
   end
 
-  test 'collection radio accepts multiple readonly items' do
-    collection = [[1, true], [0, false], [2, 'other']]
-    with_collection_radio_buttons :user, :active, collection, :last, :first, :readonly => [true, false]
+  test "collection radio accepts multiple readonly items" do
+    collection = [[1, true], [0, false], [2, "other"]]
+    with_collection_radio_buttons :user, :active, collection, :last, :first, readonly: [true, false]
 
-    assert_select 'input[type=radio][value=true][readonly=readonly]'
-    assert_select 'input[type=radio][value=false][readonly=readonly]'
-    assert_no_select 'input[type=radio][value=other][readonly=readonly]'
+    assert_select "input[type=radio][value=true][readonly=readonly]"
+    assert_select "input[type=radio][value=false][readonly=readonly]"
+    assert_no_select "input[type=radio][value=other][readonly=readonly]"
   end
 
-  test 'collection radio accepts single readonly item' do
+  test "collection radio accepts single readonly item" do
     collection = [[1, true], [0, false]]
-    with_collection_radio_buttons :user, :active, collection, :last, :first, :readonly => true
+    with_collection_radio_buttons :user, :active, collection, :last, :first, readonly: true
 
-    assert_select 'input[type=radio][value=true][readonly=readonly]'
-    assert_no_select 'input[type=radio][value=false][readonly=readonly]'
+    assert_select "input[type=radio][value=true][readonly=readonly]"
+    assert_no_select "input[type=radio][value=false][readonly=readonly]"
   end
 
-  test 'collection radio accepts html options as input' do
+  test "collection radio accepts html options as input" do
     collection = [[1, true], [0, false]]
-    with_collection_radio_buttons :user, :active, collection, :last, :first, {}, :class => 'special-radio'
+    with_collection_radio_buttons :user, :active, collection, :last, :first, {}, { class: "special-radio" }
 
-    assert_select 'input[type=radio][value=true].special-radio#user_active_true'
-    assert_select 'input[type=radio][value=false].special-radio#user_active_false'
+    assert_select "input[type=radio][value=true].special-radio#user_active_true"
+    assert_select "input[type=radio][value=false].special-radio#user_active_false"
   end
 
-  test 'collection radio accepts html options as the last element of array' do
-    collection = [[1, true, {class: 'foo'}], [0, false, {class: 'bar'}]]
+  test "collection radio accepts html options as the last element of array" do
+    collection = [[1, true, { class: "foo" }], [0, false, { class: "bar" }]]
     with_collection_radio_buttons :user, :active, collection, :second, :first
 
-    assert_select 'input[type=radio][value=true].foo#user_active_true'
-    assert_select 'input[type=radio][value=false].bar#user_active_false'
+    assert_select "input[type=radio][value=true].foo#user_active_true"
+    assert_select "input[type=radio][value=false].bar#user_active_false"
   end
 
-  test 'collection radio sets the label class defined inside the block' do
-    collection = [[1, true, {class: 'foo'}], [0, false, {class: 'bar'}]]
+  test "collection radio sets the label class defined inside the block" do
+    collection = [[1, true, { class: "foo" }], [0, false, { class: "bar" }]]
     with_collection_radio_buttons :user, :active, collection, :second, :first do |b|
       b.label(class: "collection_radio_buttons")
     end
 
-    assert_select 'label.collection_radio_buttons[for=user_active_true]'
-    assert_select 'label.collection_radio_buttons[for=user_active_false]'
+    assert_select "label.collection_radio_buttons[for=user_active_true]"
+    assert_select "label.collection_radio_buttons[for=user_active_false]"
   end
 
-  test 'collection radio does not include the input class in the respective label' do
-    collection = [[1, true, {class: 'foo'}], [0, false, {class: 'bar'}]]
+  test "collection radio does not include the input class in the respective label" do
+    collection = [[1, true, { class: "foo" }], [0, false, { class: "bar" }]]
     with_collection_radio_buttons :user, :active, collection, :second, :first
 
-    assert_no_select 'label.foo[for=user_active_true]'
-    assert_no_select 'label.bar[for=user_active_false]'
+    assert_no_select "label.foo[for=user_active_true]"
+    assert_no_select "label.bar[for=user_active_false]"
   end
 
-  test 'collection radio does not wrap input inside the label' do
+  test "collection radio does not wrap input inside the label" do
     with_collection_radio_buttons :user, :active, [true, false], :to_s, :to_s
 
-    assert_select 'input[type=radio] + label'
-    assert_no_select 'label input'
+    assert_select "input[type=radio] + label"
+    assert_no_select "label input"
   end
 
-  test 'collection radio accepts a block to render the label as radio button wrapper' do
+  test "collection radio accepts a block to render the label as radio button wrapper" do
     with_collection_radio_buttons :user, :active, [true, false], :to_s, :to_s do |b|
       b.label { b.radio_button }
     end
 
-    assert_select 'label[for=user_active_true] > input#user_active_true[type=radio]'
-    assert_select 'label[for=user_active_false] > input#user_active_false[type=radio]'
+    assert_select "label[for=user_active_true] > input#user_active_true[type=radio]"
+    assert_select "label[for=user_active_false] > input#user_active_false[type=radio]"
   end
 
-  test 'collection radio accepts a block to change the order of label and radio button' do
+  test "collection radio accepts a block to change the order of label and radio button" do
     with_collection_radio_buttons :user, :active, [true, false], :to_s, :to_s do |b|
       b.label + b.radio_button
     end
 
-    assert_select 'label[for=user_active_true] + input#user_active_true[type=radio]'
-    assert_select 'label[for=user_active_false] + input#user_active_false[type=radio]'
+    assert_select "label[for=user_active_true] + input#user_active_true[type=radio]"
+    assert_select "label[for=user_active_false] + input#user_active_false[type=radio]"
   end
 
-  test 'collection radio with block helpers accept extra html options' do
+  test "collection radio with block helpers accept extra html options" do
     with_collection_radio_buttons :user, :active, [true, false], :to_s, :to_s do |b|
-      b.label(:class => "radio_button") + b.radio_button(:class => "radio_button")
+      b.label(class: "radio_button") + b.radio_button(class: "radio_button")
     end
 
-    assert_select 'label.radio_button[for=user_active_true] + input#user_active_true.radio_button[type=radio]'
-    assert_select 'label.radio_button[for=user_active_false] + input#user_active_false.radio_button[type=radio]'
+    assert_select "label.radio_button[for=user_active_true] + input#user_active_true.radio_button[type=radio]"
+    assert_select "label.radio_button[for=user_active_false] + input#user_active_false.radio_button[type=radio]"
   end
 
-  test 'collection radio with block helpers allows access to current text and value' do
+  test "collection radio with block helpers allows access to current text and value" do
     with_collection_radio_buttons :user, :active, [true, false], :to_s, :to_s do |b|
-      b.label(:"data-value" => b.value) { b.radio_button + b.text }
+      b.label("data-value": b.value) { b.radio_button + b.text }
     end
 
-    assert_select 'label[for=user_active_true][data-value=true]', 'true' do
-      assert_select 'input#user_active_true[type=radio]'
+    assert_select "label[for=user_active_true][data-value=true]", "true" do
+      assert_select "input#user_active_true[type=radio]"
     end
-    assert_select 'label[for=user_active_false][data-value=false]', 'false' do
-      assert_select 'input#user_active_false[type=radio]'
+    assert_select "label[for=user_active_false][data-value=false]", "false" do
+      assert_select "input#user_active_false[type=radio]"
     end
   end
 
-  test 'collection radio with block helpers allows access to the current object item in the collection to access extra properties' do
+  test "collection radio with block helpers allows access to the current object item in the collection to access extra properties" do
     with_collection_radio_buttons :user, :active, [true, false], :to_s, :to_s do |b|
-      b.label(:class => b.object) { b.radio_button + b.text }
+      b.label(class: b.object) { b.radio_button + b.text }
     end
 
-    assert_select 'label.true[for=user_active_true]', 'true' do
-      assert_select 'input#user_active_true[type=radio]'
+    assert_select "label.true[for=user_active_true]", "true" do
+      assert_select "input#user_active_true[type=radio]"
     end
-    assert_select 'label.false[for=user_active_false]', 'false' do
-      assert_select 'input#user_active_false[type=radio]'
+    assert_select "label.false[for=user_active_false]", "false" do
+      assert_select "input#user_active_false[type=radio]"
     end
   end
 
-  test 'collection radio buttons with fields for' do
-    collection = [Category.new(1, 'Category 1'), Category.new(2, 'Category 2')]
+  test "collection radio buttons with fields for" do
+    collection = [Category.new(1, "Category 1"), Category.new(2, "Category 2")]
     @output_buffer = fields_for(:post) do |p|
       p.collection_radio_buttons :category_id, collection, :id, :name
     end
@@ -188,186 +196,193 @@ class FormCollectionsHelperTest < ActionView::TestCase
     assert_select 'input#post_category_id_1[type=radio][value="1"]'
     assert_select 'input#post_category_id_2[type=radio][value="2"]'
 
-    assert_select 'label[for=post_category_id_1]', 'Category 1'
-    assert_select 'label[for=post_category_id_2]', 'Category 2'
+    assert_select "label[for=post_category_id_1]", "Category 1"
+    assert_select "label[for=post_category_id_2]", "Category 2"
   end
 
-  test 'collection radio accepts checked item which has a value of false' do
-    with_collection_radio_buttons :user, :active, [[1, true], [0, false]], :last, :first, :checked => false
-    assert_no_select 'input[type=radio][value=true][checked=checked]'
-    assert_select 'input[type=radio][value=false][checked=checked]'
+  test "collection radio accepts checked item which has a value of false" do
+    with_collection_radio_buttons :user, :active, [[1, true], [0, false]], :last, :first, checked: false
+    assert_no_select "input[type=radio][value=true][checked=checked]"
+    assert_select "input[type=radio][value=false][checked=checked]"
   end
 
-  test 'collection radio buttons generates only one hidden field for the entire collection, to ensure something will be sent back to the server when posting an empty collection' do
-    collection = [Category.new(1, 'Category 1'), Category.new(2, 'Category 2')]
+  test "collection radio buttons generates only one hidden field for the entire collection, to ensure something will be sent back to the server when posting an empty collection" do
+    collection = [Category.new(1, "Category 1"), Category.new(2, "Category 2")]
     with_collection_radio_buttons :user, :category_ids, collection, :id, :name
 
     assert_select "input[type=hidden][name='user[category_ids]'][value='']", count: 1
   end
 
-  test 'collection radio buttons generates a hidden field using the given :name in :html_options' do
-    collection = [Category.new(1, 'Category 1'), Category.new(2, 'Category 2')]
+  test "collection radio buttons generates a hidden field using the given :name in :html_options" do
+    collection = [Category.new(1, "Category 1"), Category.new(2, "Category 2")]
     with_collection_radio_buttons :user, :category_ids, collection, :id, :name, {}, { name: "user[other_category_ids]" }
 
     assert_select "input[type=hidden][name='user[other_category_ids]'][value='']", count: 1
   end
 
-  test 'collection radio buttons generates a hidden field with index if it was provided' do
-    collection = [Category.new(1, 'Category 1'), Category.new(2, 'Category 2')]
-    with_collection_radio_buttons :user, :category_ids, collection, :id, :name, { index: 322 }
+  test "collection radio buttons generates a hidden field with index if it was provided" do
+    collection = [Category.new(1, "Category 1"), Category.new(2, "Category 2")]
+    with_collection_radio_buttons :user, :category_ids, collection, :id, :name, index: 322
 
     assert_select "input[type=hidden][name='user[322][category_ids]'][value='']", count: 1
   end
 
-  test 'collection radio buttons does not generate a hidden field if include_hidden option is false' do
-    collection = [Category.new(1, 'Category 1'), Category.new(2, 'Category 2')]
+  test "collection radio buttons does not generate a hidden field if include_hidden option is false" do
+    collection = [Category.new(1, "Category 1"), Category.new(2, "Category 2")]
     with_collection_radio_buttons :user, :category_ids, collection, :id, :name, include_hidden: false
 
     assert_select "input[type=hidden][name='user[category_ids]'][value='']", count: 0
   end
 
-  test 'collection radio buttons does not generate a hidden field if include_hidden option is false with key as string' do
-    collection = [Category.new(1, 'Category 1'), Category.new(2, 'Category 2')]
-    with_collection_radio_buttons :user, :category_ids, collection, :id, :name, 'include_hidden' => false
+  test "collection radio buttons does not generate a hidden field if include_hidden option is false with key as string" do
+    collection = [Category.new(1, "Category 1"), Category.new(2, "Category 2")]
+    with_collection_radio_buttons :user, :category_ids, collection, :id, :name, "include_hidden" => false
 
     assert_select "input[type=hidden][name='user[category_ids]'][value='']", count: 0
   end
 
   # COLLECTION CHECK BOXES
-  test 'collection check boxes accepts a collection and generate a series of checkboxes for value method' do
-    collection = [Category.new(1, 'Category 1'), Category.new(2, 'Category 2')]
+  test "collection check boxes accepts a collection and generate a series of checkboxes for value method" do
+    collection = [Category.new(1, "Category 1"), Category.new(2, "Category 2")]
     with_collection_check_boxes :user, :category_ids, collection, :id, :name
 
     assert_select 'input#user_category_ids_1[type=checkbox][value="1"]'
     assert_select 'input#user_category_ids_2[type=checkbox][value="2"]'
   end
 
-  test 'collection check boxes generates only one hidden field for the entire collection, to ensure something will be sent back to the server when posting an empty collection' do
-    collection = [Category.new(1, 'Category 1'), Category.new(2, 'Category 2')]
+  test "collection check boxes generates only one hidden field for the entire collection, to ensure something will be sent back to the server when posting an empty collection" do
+    collection = [Category.new(1, "Category 1"), Category.new(2, "Category 2")]
     with_collection_check_boxes :user, :category_ids, collection, :id, :name
 
-    assert_select "input[type=hidden][name='user[category_ids][]'][value='']", :count => 1
+    assert_select "input[type=hidden][name='user[category_ids][]'][value='']", count: 1
   end
 
-  test 'collection check boxes generates a hidden field using the given :name in :html_options' do
-    collection = [Category.new(1, 'Category 1'), Category.new(2, 'Category 2')]
-    with_collection_check_boxes :user, :category_ids, collection, :id, :name, {}, {name: "user[other_category_ids][]"}
+  test "collection check boxes generates a hidden field using the given :name in :html_options" do
+    collection = [Category.new(1, "Category 1"), Category.new(2, "Category 2")]
+    with_collection_check_boxes :user, :category_ids, collection, :id, :name, {}, { name: "user[other_category_ids][]" }
 
-    assert_select "input[type=hidden][name='user[other_category_ids][]'][value='']", :count => 1
+    assert_select "input[type=hidden][name='user[other_category_ids][]'][value='']", count: 1
   end
 
-  test 'collection check boxes generates a hidden field with index if it was provided' do
-    collection = [Category.new(1, 'Category 1'), Category.new(2, 'Category 2')]
-    with_collection_check_boxes :user, :category_ids, collection, :id, :name, { index: 322 }
+  test "collection check boxes generates a hidden field with index if it was provided" do
+    collection = [Category.new(1, "Category 1"), Category.new(2, "Category 2")]
+    with_collection_check_boxes :user, :category_ids, collection, :id, :name, index: 322
 
     assert_select "input[type=hidden][name='user[322][category_ids][]'][value='']", count: 1
   end
 
-  test 'collection check boxes does not generate a hidden field if include_hidden option is false' do
-    collection = [Category.new(1, 'Category 1'), Category.new(2, 'Category 2')]
+  test "collection check boxes does not generate a hidden field if include_hidden option is false" do
+    collection = [Category.new(1, "Category 1"), Category.new(2, "Category 2")]
     with_collection_check_boxes :user, :category_ids, collection, :id, :name, include_hidden: false
 
-    assert_select "input[type=hidden][name='user[category_ids][]'][value='']", :count => 0
+    assert_select "input[type=hidden][name='user[category_ids][]'][value='']", count: 0
   end
 
-  test 'collection check boxes does not generate a hidden field if include_hidden option is false with key as string' do
-    collection = [Category.new(1, 'Category 1'), Category.new(2, 'Category 2')]
-    with_collection_check_boxes :user, :category_ids, collection, :id, :name, 'include_hidden' => false
+  test "collection check boxes does not generate a hidden field if include_hidden option is false with key as string" do
+    collection = [Category.new(1, "Category 1"), Category.new(2, "Category 2")]
+    with_collection_check_boxes :user, :category_ids, collection, :id, :name, "include_hidden" => false
 
     assert_select "input[type=hidden][name='user[category_ids][]'][value='']", count: 0
   end
 
-  test 'collection check boxes accepts a collection and generate a series of checkboxes with labels for label method' do
-    collection = [Category.new(1, 'Category 1'), Category.new(2, 'Category 2')]
+  test "collection check boxes accepts a collection and generate a series of checkboxes with labels for label method" do
+    collection = [Category.new(1, "Category 1"), Category.new(2, "Category 2")]
     with_collection_check_boxes :user, :category_ids, collection, :id, :name
 
-    assert_select 'label[for=user_category_ids_1]', 'Category 1'
-    assert_select 'label[for=user_category_ids_2]', 'Category 2'
+    assert_select "label[for=user_category_ids_1]", "Category 1"
+    assert_select "label[for=user_category_ids_2]", "Category 2"
   end
 
-  test 'collection check boxes handles camelized collection values for labels correctly' do
-    with_collection_check_boxes :user, :active, ['Yes', 'No'], :to_s, :to_s
+  test "collection check boxes handles camelized collection values for labels correctly" do
+    with_collection_check_boxes :user, :active, ["Yes", "No"], :to_s, :to_s
+
+    assert_select "label[for=user_active_yes]", "Yes"
+    assert_select "label[for=user_active_no]", "No"
+  end
 
-    assert_select 'label[for=user_active_yes]', 'Yes'
-    assert_select 'label[for=user_active_no]', 'No'
+  test "collection check box should sanitize collection values for labels correctly" do
+    with_collection_check_boxes :user, :name, ["$0.99", "$1.99"], :to_s, :to_s
+    assert_select "label[for=user_name_099]", "$0.99"
+    assert_select "label[for=user_name_199]", "$1.99"
   end
 
-  test 'collection check box should sanitize collection values for labels correctly' do
-    with_collection_check_boxes :user, :name, ['$0.99', '$1.99'], :to_s, :to_s
-    assert_select 'label[for=user_name_099]', '$0.99'
-    assert_select 'label[for=user_name_199]', '$1.99'
+  test "collection check boxes generates labels for non-English values correctly" do
+    with_collection_check_boxes :user, :title, ["Господин", "Госпожа"], :to_s, :to_s
+
+    assert_select "input[type=checkbox]#user_title_господин"
+    assert_select "label[for=user_title_господин]", "Господин"
   end
 
-  test 'collection check boxes accepts html options as the last element of array' do
-    collection = [[1, 'Category 1', {class: 'foo'}], [2, 'Category 2', {class: 'bar'}]]
+  test "collection check boxes accepts html options as the last element of array" do
+    collection = [[1, "Category 1", { class: "foo" }], [2, "Category 2", { class: "bar" }]]
     with_collection_check_boxes :user, :active, collection, :first, :second
 
     assert_select 'input[type=checkbox][value="1"].foo'
     assert_select 'input[type=checkbox][value="2"].bar'
   end
 
-  test 'collection check boxes propagates input id to the label for attribute' do
-    collection = [[1, 'Category 1', {id: 'foo'}], [2, 'Category 2', {id: 'bar'}]]
+  test "collection check boxes propagates input id to the label for attribute" do
+    collection = [[1, "Category 1", { id: "foo" }], [2, "Category 2", { id: "bar" }]]
     with_collection_check_boxes :user, :active, collection, :first, :second
 
     assert_select 'input[type=checkbox][value="1"]#foo'
     assert_select 'input[type=checkbox][value="2"]#bar'
 
-    assert_select 'label[for=foo]'
-    assert_select 'label[for=bar]'
+    assert_select "label[for=foo]"
+    assert_select "label[for=bar]"
   end
 
-  test 'collection check boxes sets the label class defined inside the block' do
-    collection = [[1, 'Category 1', {class: 'foo'}], [2, 'Category 2', {class: 'bar'}]]
+  test "collection check boxes sets the label class defined inside the block" do
+    collection = [[1, "Category 1", { class: "foo" }], [2, "Category 2", { class: "bar" }]]
     with_collection_check_boxes :user, :active, collection, :second, :first do |b|
-      b.label(class: 'collection_check_boxes')
+      b.label(class: "collection_check_boxes")
     end
 
-    assert_select 'label.collection_check_boxes[for=user_active_category_1]'
-    assert_select 'label.collection_check_boxes[for=user_active_category_2]'
+    assert_select "label.collection_check_boxes[for=user_active_category_1]"
+    assert_select "label.collection_check_boxes[for=user_active_category_2]"
   end
 
-  test 'collection check boxes does not include the input class in the respective label' do
-    collection = [[1, 'Category 1', {class: 'foo'}], [2, 'Category 2', {class: 'bar'}]]
+  test "collection check boxes does not include the input class in the respective label" do
+    collection = [[1, "Category 1", { class: "foo" }], [2, "Category 2", { class: "bar" }]]
     with_collection_check_boxes :user, :active, collection, :second, :first
 
-    assert_no_select 'label.foo[for=user_active_category_1]'
-    assert_no_select 'label.bar[for=user_active_category_2]'
+    assert_no_select "label.foo[for=user_active_category_1]"
+    assert_no_select "label.bar[for=user_active_category_2]"
   end
 
-  test 'collection check boxes accepts selected values as :checked option' do
-    collection = (1..3).map{|i| [i, "Category #{i}"] }
-    with_collection_check_boxes :user, :category_ids, collection, :first, :last, :checked => [1, 3]
+  test "collection check boxes accepts selected values as :checked option" do
+    collection = (1..3).map { |i| [i, "Category #{i}"] }
+    with_collection_check_boxes :user, :category_ids, collection, :first, :last, checked: [1, 3]
 
     assert_select 'input[type=checkbox][value="1"][checked=checked]'
     assert_select 'input[type=checkbox][value="3"][checked=checked]'
     assert_no_select 'input[type=checkbox][value="2"][checked=checked]'
   end
 
-  test 'collection check boxes accepts selected string values as :checked option' do
-    collection = (1..3).map{|i| [i, "Category #{i}"] }
-    with_collection_check_boxes :user, :category_ids, collection, :first, :last, :checked => ['1', '3']
+  test "collection check boxes accepts selected string values as :checked option" do
+    collection = (1..3).map { |i| [i, "Category #{i}"] }
+    with_collection_check_boxes :user, :category_ids, collection, :first, :last, checked: ["1", "3"]
 
     assert_select 'input[type=checkbox][value="1"][checked=checked]'
     assert_select 'input[type=checkbox][value="3"][checked=checked]'
     assert_no_select 'input[type=checkbox][value="2"][checked=checked]'
   end
 
-  test 'collection check boxes accepts a single checked value' do
-    collection = (1..3).map{|i| [i, "Category #{i}"] }
-    with_collection_check_boxes :user, :category_ids, collection, :first, :last, :checked => 3
+  test "collection check boxes accepts a single checked value" do
+    collection = (1..3).map { |i| [i, "Category #{i}"] }
+    with_collection_check_boxes :user, :category_ids, collection, :first, :last, checked: 3
 
     assert_select 'input[type=checkbox][value="3"][checked=checked]'
     assert_no_select 'input[type=checkbox][value="1"][checked=checked]'
     assert_no_select 'input[type=checkbox][value="2"][checked=checked]'
   end
 
-  test 'collection check boxes accepts selected values as :checked option and override the model values' do
+  test "collection check boxes accepts selected values as :checked option and override the model values" do
     user = Struct.new(:category_ids).new(2)
-    collection = (1..3).map{|i| [i, "Category #{i}"] }
+    collection = (1..3).map { |i| [i, "Category #{i}"] }
 
     @output_buffer = fields_for(:user, user) do |p|
-      p.collection_check_boxes :category_ids, collection, :first, :last, :checked => [1, 3]
+      p.collection_check_boxes :category_ids, collection, :first, :last, checked: [1, 3]
     end
 
     assert_select 'input[type=checkbox][value="1"][checked=checked]'
@@ -375,70 +390,70 @@ class FormCollectionsHelperTest < ActionView::TestCase
     assert_no_select 'input[type=checkbox][value="2"][checked=checked]'
   end
 
-  test 'collection check boxes accepts multiple disabled items' do
-    collection = (1..3).map{|i| [i, "Category #{i}"] }
-    with_collection_check_boxes :user, :category_ids, collection, :first, :last, :disabled => [1, 3]
+  test "collection check boxes accepts multiple disabled items" do
+    collection = (1..3).map { |i| [i, "Category #{i}"] }
+    with_collection_check_boxes :user, :category_ids, collection, :first, :last, disabled: [1, 3]
 
     assert_select 'input[type=checkbox][value="1"][disabled=disabled]'
     assert_select 'input[type=checkbox][value="3"][disabled=disabled]'
     assert_no_select 'input[type=checkbox][value="2"][disabled=disabled]'
   end
 
-  test 'collection check boxes accepts single disabled item' do
-    collection = (1..3).map{|i| [i, "Category #{i}"] }
-    with_collection_check_boxes :user, :category_ids, collection, :first, :last, :disabled => 1
+  test "collection check boxes accepts single disabled item" do
+    collection = (1..3).map { |i| [i, "Category #{i}"] }
+    with_collection_check_boxes :user, :category_ids, collection, :first, :last, disabled: 1
 
     assert_select 'input[type=checkbox][value="1"][disabled=disabled]'
     assert_no_select 'input[type=checkbox][value="3"][disabled=disabled]'
     assert_no_select 'input[type=checkbox][value="2"][disabled=disabled]'
   end
 
-  test 'collection check boxes accepts a proc to disabled items' do
-    collection = (1..3).map{|i| [i, "Category #{i}"] }
-    with_collection_check_boxes :user, :category_ids, collection, :first, :last, :disabled => proc { |i| i.first == 1 }
+  test "collection check boxes accepts a proc to disabled items" do
+    collection = (1..3).map { |i| [i, "Category #{i}"] }
+    with_collection_check_boxes :user, :category_ids, collection, :first, :last, disabled: proc { |i| i.first == 1 }
 
     assert_select 'input[type=checkbox][value="1"][disabled=disabled]'
     assert_no_select 'input[type=checkbox][value="3"][disabled=disabled]'
     assert_no_select 'input[type=checkbox][value="2"][disabled=disabled]'
   end
 
-  test 'collection check boxes accepts multiple readonly items' do
-    collection = (1..3).map{|i| [i, "Category #{i}"] }
-    with_collection_check_boxes :user, :category_ids, collection, :first, :last, :readonly => [1, 3]
+  test "collection check boxes accepts multiple readonly items" do
+    collection = (1..3).map { |i| [i, "Category #{i}"] }
+    with_collection_check_boxes :user, :category_ids, collection, :first, :last, readonly: [1, 3]
 
     assert_select 'input[type=checkbox][value="1"][readonly=readonly]'
     assert_select 'input[type=checkbox][value="3"][readonly=readonly]'
     assert_no_select 'input[type=checkbox][value="2"][readonly=readonly]'
   end
 
-  test 'collection check boxes accepts single readonly item' do
-    collection = (1..3).map{|i| [i, "Category #{i}"] }
-    with_collection_check_boxes :user, :category_ids, collection, :first, :last, :readonly => 1
+  test "collection check boxes accepts single readonly item" do
+    collection = (1..3).map { |i| [i, "Category #{i}"] }
+    with_collection_check_boxes :user, :category_ids, collection, :first, :last, readonly: 1
 
     assert_select 'input[type=checkbox][value="1"][readonly=readonly]'
     assert_no_select 'input[type=checkbox][value="3"][readonly=readonly]'
     assert_no_select 'input[type=checkbox][value="2"][readonly=readonly]'
   end
 
-  test 'collection check boxes accepts a proc to readonly items' do
-    collection = (1..3).map{|i| [i, "Category #{i}"] }
-    with_collection_check_boxes :user, :category_ids, collection, :first, :last, :readonly => proc { |i| i.first == 1 }
+  test "collection check boxes accepts a proc to readonly items" do
+    collection = (1..3).map { |i| [i, "Category #{i}"] }
+    with_collection_check_boxes :user, :category_ids, collection, :first, :last, readonly: proc { |i| i.first == 1 }
 
     assert_select 'input[type=checkbox][value="1"][readonly=readonly]'
     assert_no_select 'input[type=checkbox][value="3"][readonly=readonly]'
     assert_no_select 'input[type=checkbox][value="2"][readonly=readonly]'
   end
 
-  test 'collection check boxes accepts html options' do
-    collection = [[1, 'Category 1'], [2, 'Category 2']]
-    with_collection_check_boxes :user, :category_ids, collection, :first, :last, {}, :class => 'check'
+  test "collection check boxes accepts html options" do
+    collection = [[1, "Category 1"], [2, "Category 2"]]
+    with_collection_check_boxes :user, :category_ids, collection, :first, :last, {}, { class: "check" }
 
     assert_select 'input.check[type=checkbox][value="1"]'
     assert_select 'input.check[type=checkbox][value="2"]'
   end
 
-  test 'collection check boxes with fields for' do
-    collection = [Category.new(1, 'Category 1'), Category.new(2, 'Category 2')]
+  test "collection check boxes with fields for" do
+    collection = [Category.new(1, "Category 1"), Category.new(2, "Category 2")]
     @output_buffer = fields_for(:post) do |p|
       p.collection_check_boxes :category_ids, collection, :id, :name
     end
@@ -446,67 +461,67 @@ class FormCollectionsHelperTest < ActionView::TestCase
     assert_select 'input#post_category_ids_1[type=checkbox][value="1"]'
     assert_select 'input#post_category_ids_2[type=checkbox][value="2"]'
 
-    assert_select 'label[for=post_category_ids_1]', 'Category 1'
-    assert_select 'label[for=post_category_ids_2]', 'Category 2'
+    assert_select "label[for=post_category_ids_1]", "Category 1"
+    assert_select "label[for=post_category_ids_2]", "Category 2"
   end
 
-  test 'collection check boxes does not wrap input inside the label' do
+  test "collection check boxes does not wrap input inside the label" do
     with_collection_check_boxes :user, :active, [true, false], :to_s, :to_s
 
-    assert_select 'input[type=checkbox] + label'
-    assert_no_select 'label input'
+    assert_select "input[type=checkbox] + label"
+    assert_no_select "label input"
   end
 
-  test 'collection check boxes accepts a block to render the label as check box wrapper' do
+  test "collection check boxes accepts a block to render the label as check box wrapper" do
     with_collection_check_boxes :user, :active, [true, false], :to_s, :to_s do |b|
       b.label { b.check_box }
     end
 
-    assert_select 'label[for=user_active_true] > input#user_active_true[type=checkbox]'
-    assert_select 'label[for=user_active_false] > input#user_active_false[type=checkbox]'
+    assert_select "label[for=user_active_true] > input#user_active_true[type=checkbox]"
+    assert_select "label[for=user_active_false] > input#user_active_false[type=checkbox]"
   end
 
-  test 'collection check boxes accepts a block to change the order of label and check box' do
+  test "collection check boxes accepts a block to change the order of label and check box" do
     with_collection_check_boxes :user, :active, [true, false], :to_s, :to_s do |b|
       b.label + b.check_box
     end
 
-    assert_select 'label[for=user_active_true] + input#user_active_true[type=checkbox]'
-    assert_select 'label[for=user_active_false] + input#user_active_false[type=checkbox]'
+    assert_select "label[for=user_active_true] + input#user_active_true[type=checkbox]"
+    assert_select "label[for=user_active_false] + input#user_active_false[type=checkbox]"
   end
 
-  test 'collection check boxes with block helpers accept extra html options' do
+  test "collection check boxes with block helpers accept extra html options" do
     with_collection_check_boxes :user, :active, [true, false], :to_s, :to_s do |b|
-      b.label(:class => "check_box") + b.check_box(:class => "check_box")
+      b.label(class: "check_box") + b.check_box(class: "check_box")
     end
 
-    assert_select 'label.check_box[for=user_active_true] + input#user_active_true.check_box[type=checkbox]'
-    assert_select 'label.check_box[for=user_active_false] + input#user_active_false.check_box[type=checkbox]'
+    assert_select "label.check_box[for=user_active_true] + input#user_active_true.check_box[type=checkbox]"
+    assert_select "label.check_box[for=user_active_false] + input#user_active_false.check_box[type=checkbox]"
   end
 
-  test 'collection check boxes with block helpers allows access to current text and value' do
+  test "collection check boxes with block helpers allows access to current text and value" do
     with_collection_check_boxes :user, :active, [true, false], :to_s, :to_s do |b|
-      b.label(:"data-value" => b.value) { b.check_box + b.text }
+      b.label("data-value": b.value) { b.check_box + b.text }
     end
 
-    assert_select 'label[for=user_active_true][data-value=true]', 'true' do
-      assert_select 'input#user_active_true[type=checkbox]'
+    assert_select "label[for=user_active_true][data-value=true]", "true" do
+      assert_select "input#user_active_true[type=checkbox]"
     end
-    assert_select 'label[for=user_active_false][data-value=false]', 'false' do
-      assert_select 'input#user_active_false[type=checkbox]'
+    assert_select "label[for=user_active_false][data-value=false]", "false" do
+      assert_select "input#user_active_false[type=checkbox]"
     end
   end
 
-  test 'collection check boxes with block helpers allows access to the current object item in the collection to access extra properties' do
+  test "collection check boxes with block helpers allows access to the current object item in the collection to access extra properties" do
     with_collection_check_boxes :user, :active, [true, false], :to_s, :to_s do |b|
-      b.label(:class => b.object) { b.check_box + b.text }
+      b.label(class: b.object) { b.check_box + b.text }
     end
 
-    assert_select 'label.true[for=user_active_true]', 'true' do
-      assert_select 'input#user_active_true[type=checkbox]'
+    assert_select "label.true[for=user_active_true]", "true" do
+      assert_select "input#user_active_true[type=checkbox]"
     end
-    assert_select 'label.false[for=user_active_false]', 'false' do
-      assert_select 'input#user_active_false[type=checkbox]'
+    assert_select "label.false[for=user_active_false]", "false" do
+      assert_select "input#user_active_false[type=checkbox]"
     end
   end
 end
diff --git a/actionview/test/template/form_helper/form_with_test.rb b/actionview/test/template/form_helper/form_with_test.rb
new file mode 100644
index 0000000000..0295ff627d
--- /dev/null
+++ b/actionview/test/template/form_helper/form_with_test.rb
@@ -0,0 +1,2276 @@
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "controller/fake_models"
+
+class FormWithTest < ActionView::TestCase
+  include RenderERBUtils
+
+  setup do
+    @old_value = ActionView::Helpers::FormHelper.form_with_generates_ids
+    ActionView::Helpers::FormHelper.form_with_generates_ids = true
+  end
+
+  teardown do
+    ActionView::Helpers::FormHelper.form_with_generates_ids = @old_value
+  end
+end
+
+class FormWithActsLikeFormTagTest < FormWithTest
+  tests ActionView::Helpers::FormTagHelper
+
+  setup do
+    @controller = BasicController.new
+  end
+
+  def hidden_fields(options = {})
+    method = options[:method]
+    skip_enforcing_utf8 = options.fetch(:skip_enforcing_utf8, false)
+
+    "".dup.tap do |txt|
+      unless skip_enforcing_utf8
+        txt << %{<input name="utf8" type="hidden" value="&#x2713;" />}
+      end
+
+      if method && !%w(get post).include?(method.to_s)
+        txt << %{<input name="_method" type="hidden" value="#{method}" />}
+      end
+    end
+  end
+
+  def form_text(action = "http://www.example.com", local: false, **options)
+    enctype, html_class, id, method = options.values_at(:enctype, :html_class, :id, :method)
+
+    method = method.to_s == "get" ? "get" : "post"
+
+    txt =  %{<form accept-charset="UTF-8" action="#{action}"}.dup
+    txt << %{ enctype="multipart/form-data"} if enctype
+    txt << %{ data-remote="true"} unless local
+    txt << %{ class="#{html_class}"} if html_class
+    txt << %{ id="#{id}"} if id
+    txt << %{ method="#{method}">}
+  end
+
+  def whole_form(action = "http://www.example.com", options = {})
+    out = form_text(action, options) + hidden_fields(options)
+
+    if block_given?
+      out << yield << "</form>"
+    end
+
+    out
+  end
+
+  def url_for(options)
+    if options.is_a?(Hash)
+      "http://www.example.com"
+    else
+      super
+    end
+  end
+
+  def test_form_with_multipart
+    actual = form_with(multipart: true)
+
+    expected = whole_form("http://www.example.com", enctype: true)
+    assert_dom_equal expected, actual
+  end
+
+  def test_form_with_with_method_patch
+    actual = form_with(method: :patch)
+
+    expected = whole_form("http://www.example.com", method: :patch)
+    assert_dom_equal expected, actual
+  end
+
+  def test_form_with_with_method_put
+    actual = form_with(method: :put)
+
+    expected = whole_form("http://www.example.com", method: :put)
+    assert_dom_equal expected, actual
+  end
+
+  def test_form_with_with_method_delete
+    actual = form_with(method: :delete)
+
+    expected = whole_form("http://www.example.com", method: :delete)
+    assert_dom_equal expected, actual
+  end
+
+  def test_form_with_with_local_true
+    actual = form_with(local: true)
+
+    expected = whole_form("http://www.example.com", local: true)
+    assert_dom_equal expected, actual
+  end
+
+  def test_form_with_skip_enforcing_utf8_true
+    actual = form_with(skip_enforcing_utf8: true)
+    expected = whole_form("http://www.example.com", skip_enforcing_utf8: true)
+    assert_dom_equal expected, actual
+    assert actual.html_safe?
+  end
+
+  def test_form_with_with_block_in_erb
+    output_buffer = render_erb("<%= form_with(url: 'http://www.example.com') do %>Hello world!<% end %>")
+
+    expected = whole_form { "Hello world!" }
+    assert_dom_equal expected, output_buffer
+  end
+
+  def test_form_with_with_block_and_method_in_erb
+    output_buffer = render_erb("<%= form_with(url: 'http://www.example.com', method: :put) do %>Hello world!<% end %>")
+
+    expected = whole_form("http://www.example.com", method: "put") do
+      "Hello world!"
+    end
+
+    assert_dom_equal expected, output_buffer
+  end
+
+  def test_form_with_with_block_in_erb_and_local_true
+    output_buffer = render_erb("<%= form_with(url: 'http://www.example.com', local: true) do %>Hello world!<% end %>")
+
+    expected = whole_form("http://www.example.com", local: true) do
+      "Hello world!"
+    end
+
+    assert_dom_equal expected, output_buffer
+  end
+end
+
+class FormWithActsLikeFormForTest < FormWithTest
+  def form_with(*)
+    @output_buffer = super
+  end
+
+  teardown do
+    I18n.backend.reload!
+  end
+
+  setup do
+    # Create "label" locale for testing I18n label helpers
+    I18n.backend.store_translations "label",
+      activemodel: {
+        attributes: {
+          post: {
+            cost: "Total cost"
+          },
+          "post/language": {
+            spanish: "Espanol"
+          }
+        }
+      },
+      helpers: {
+        label: {
+          post: {
+            body: "Write entire text here",
+            color: {
+              red: "Rojo"
+            },
+            comments: {
+              body: "Write body here"
+            }
+          },
+          tag: {
+            value: "Tag"
+          },
+          post_delegate: {
+            title: "Delegate model_name title"
+          }
+        }
+      }
+
+    # Create "submit" locale for testing I18n submit helpers
+    I18n.backend.store_translations "submit",
+      helpers: {
+        submit: {
+          create: "Create %{model}",
+          update: "Confirm %{model} changes",
+          submit: "Save changes",
+          another_post: {
+            update: "Update your %{model}"
+          }
+        }
+      }
+
+    I18n.backend.store_translations "placeholder",
+      activemodel: {
+        attributes: {
+          post: {
+            cost: "Total cost"
+          },
+          "post/cost": {
+            uk: "Pounds"
+          }
+        }
+      },
+      helpers: {
+        placeholder: {
+          post: {
+            title: "What is this about?",
+            written_on: {
+              spanish: "Escrito en"
+            },
+            comments: {
+              body: "Write body here"
+            }
+          },
+          post_delegate: {
+            title: "Delegate model_name title"
+          },
+          tag: {
+            value: "Tag"
+          }
+        }
+      }
+
+    @post = Post.new
+    @comment = Comment.new
+    def @post.errors
+      Class.new {
+        def [](field); field == "author_name" ? ["can't be empty"] : [] end
+        def empty?() false end
+        def count() 1 end
+        def full_messages() ["Author name can't be empty"] end
+      }.new
+    end
+    def @post.to_key; [123]; end
+    def @post.id; 0; end
+    def @post.id_before_type_cast; "omg"; end
+    def @post.id_came_from_user?; true; end
+    def @post.to_param; "123"; end
+
+    @post.persisted   = true
+    @post.title       = "Hello World"
+    @post.author_name = ""
+    @post.body        = "Back to the hill and over it again!"
+    @post.secret      = 1
+    @post.written_on  = Date.new(2004, 6, 15)
+
+    @post.comments = []
+    @post.comments << @comment
+
+    @post.tags = []
+    @post.tags << Tag.new
+
+    @post_delegator = PostDelegator.new
+
+    @post_delegator.title = "Hello World"
+
+    @car = Car.new("#000FFF")
+  end
+
+  Routes = ActionDispatch::Routing::RouteSet.new
+  Routes.draw do
+    resources :posts do
+      resources :comments
+    end
+
+    namespace :admin do
+      resources :posts do
+        resources :comments
+      end
+    end
+
+    get "/foo", to: "controller#action"
+    root to: "main#index"
+  end
+
+  def _routes
+    Routes
+  end
+
+  include Routes.url_helpers
+
+  def url_for(object)
+    @url_for_options = object
+
+    if object.is_a?(Hash) && object[:use_route].blank? && object[:controller].blank?
+      object.merge!(controller: "main", action: "index")
+    end
+
+    super
+  end
+
+  def test_form_with_requires_arguments
+    error = assert_raises(ArgumentError) do
+      form_for(nil, html: { id: "create-post" }) do
+      end
+    end
+    assert_equal "First argument in form cannot contain nil or be empty", error.message
+
+    error = assert_raises(ArgumentError) do
+      form_for([nil, nil], html: { id: "create-post" }) do
+      end
+    end
+    assert_equal "First argument in form cannot contain nil or be empty", error.message
+  end
+
+  def test_form_with
+    form_with(model: @post, id: "create-post") do |f|
+      concat f.label(:title) { "The Title" }
+      concat f.text_field(:title)
+      concat f.text_area(:body)
+      concat f.check_box(:secret)
+      concat f.select(:category, %w( animal economy sports ))
+      concat f.submit("Create post")
+      concat f.button("Create post")
+      concat f.button {
+        concat content_tag(:span, "Create post")
+      }
+    end
+
+    expected = whole_form("/posts/123", "create-post", method: "patch") do
+      "<label for='post_title'>The Title</label>" \
+      "<input name='post[title]' type='text' value='Hello World' id='post_title' />" \
+      "<textarea name='post[body]' id='post_body'>\nBack to the hill and over it again!</textarea>" \
+      "<input name='post[secret]' type='hidden' value='0' />" \
+      "<input name='post[secret]' checked='checked' type='checkbox' value='1' id='post_secret' />" \
+      "<select name='post[category]' id='post_category'><option value='animal'>animal</option>\n<option value='economy'>economy</option>\n<option value='sports'>sports</option></select>" \
+      "<input name='commit' data-disable-with='Create post' type='submit' value='Create post' />" \
+      "<button name='button' type='submit'>Create post</button>" \
+      "<button name='button' type='submit'><span>Create post</span></button>"
+    end
+
+    assert_dom_equal expected, output_buffer
+  end
+
+  def test_form_with_not_outputting_ids
+    old_value = ActionView::Helpers::FormHelper.form_with_generates_ids
+    ActionView::Helpers::FormHelper.form_with_generates_ids = false
+
+    form_with(model: @post, id: "create-post") do |f|
+      concat f.label(:title) { "The Title" }
+      concat f.text_field(:title)
+      concat f.text_area(:body)
+      concat f.check_box(:secret)
+      concat f.select(:category, %w( animal economy sports ))
+      concat f.submit("Create post")
+    end
+
+    expected = whole_form("/posts/123", "create-post", method: "patch") do
+      "<label>The Title</label>" \
+      "<input name='post[title]' type='text' value='Hello World' />" \
+      "<textarea name='post[body]'>\nBack to the hill and over it again!</textarea>" \
+      "<input name='post[secret]' type='hidden' value='0' />" \
+      "<input name='post[secret]' checked='checked' type='checkbox' value='1' />" \
+      "<select name='post[category]'><option value='animal'>animal</option>\n<option value='economy'>economy</option>\n<option value='sports'>sports</option></select>" \
+      "<input name='commit' data-disable-with='Create post' type='submit' value='Create post' />"
+    end
+
+    assert_dom_equal expected, output_buffer
+  ensure
+    ActionView::Helpers::FormHelper.form_with_generates_ids = old_value
+  end
+
+  def test_form_with_only_url_on_create
+    form_with(url: "/posts") do |f|
+      concat f.label :title, "Label me"
+      concat f.text_field :title
+    end
+
+    expected = whole_form("/posts") do
+      '<label for="title">Label me</label>' \
+      '<input type="text" name="title" id="title">'
+    end
+
+    assert_dom_equal expected, output_buffer
+  end
+
+  def test_form_with_only_url_on_update
+    form_with(url: "/posts/123") do |f|
+      concat f.label :title, "Label me"
+      concat f.text_field :title
+    end
+
+    expected = whole_form("/posts/123") do
+      '<label for="title">Label me</label>' \
+      '<input type="text" name="title" id="title">'
+    end
+
+    assert_dom_equal expected, output_buffer
+  end
+
+  def test_form_with_general_attributes
+    form_with(url: "/posts/123") do |f|
+      concat f.text_field :no_model_to_back_this_badboy
+    end
+
+    expected = whole_form("/posts/123") do
+      '<input type="text" name="no_model_to_back_this_badboy" id="no_model_to_back_this_badboy" >'
+    end
+
+    assert_dom_equal expected, output_buffer
+  end
+
+  def test_form_with_attribute_not_on_model
+    form_with(model: @post) do |f|
+      concat f.text_field :this_dont_exist_on_post
+    end
+
+    expected = whole_form("/posts/123", method: :patch) do
+      '<input type="text" name="post[this_dont_exist_on_post]" id="post_this_dont_exist_on_post" >'
+    end
+
+    assert_dom_equal expected, output_buffer
+  end
+
+  def test_form_with_doesnt_call_private_or_protected_properties_on_form_object_skipping_value
+    obj = Class.new do
+      private def private_property
+        "That would be great."
+      end
+
+      protected def protected_property
+        "I believe you have my stapler."
+      end
+    end.new
+
+    form_with(model: obj, scope: "other_name", url: "/", id: "edit-other-name") do |f|
+      assert_dom_equal '<input type="hidden" name="other_name[private_property]" id="other_name_private_property">', f.hidden_field(:private_property)
+      assert_dom_equal '<input type="hidden" name="other_name[protected_property]"  id="other_name_protected_property">', f.hidden_field(:protected_property)
+    end
+  end
+
+  def test_form_with_with_collection_radio_buttons
+    post = Post.new
+    def post.active; false; end
+    form_with(model: post) do |f|
+      concat f.collection_radio_buttons(:active, [true, false], :to_s, :to_s)
+    end
+
+    expected = whole_form("/posts") do
+      "<input type='hidden' name='post[active]' value='' />" \
+      "<input name='post[active]' type='radio' value='true' id='post_active_true' />" \
+      "<label for='post_active_true'>true</label>" \
+      "<input checked='checked' name='post[active]' type='radio' value='false' id='post_active_false' />" \
+      "<label for='post_active_false'>false</label>"
+    end
+
+    assert_dom_equal expected, output_buffer
+  end
+
+  def test_form_with_with_collection_radio_buttons_with_custom_builder_block
+    post = Post.new
+    def post.active; false; end
+
+    form_with(model: post) do |f|
+      rendered_radio_buttons = f.collection_radio_buttons(:active, [true, false], :to_s, :to_s) do |b|
+        b.label { b.radio_button + b.text }
+      end
+      concat rendered_radio_buttons
+    end
+
+    expected = whole_form("/posts") do
+      "<input type='hidden' name='post[active]' value='' />" \
+      "<label for='post_active_true'>" \
+      "<input name='post[active]' type='radio' value='true' id='post_active_true' />" \
+      "true</label>" \
+      "<label for='post_active_false'>" \
+      "<input checked='checked' name='post[active]' type='radio' value='false' id='post_active_false' />" \
+      "false</label>"
+    end
+
+    assert_dom_equal expected, output_buffer
+  end
+
+  def test_form_with_with_collection_radio_buttons_with_custom_builder_block_does_not_leak_the_template
+    post = Post.new
+    def post.active; false; end
+    def post.id; 1; end
+
+    form_with(model: post) do |f|
+      rendered_radio_buttons = f.collection_radio_buttons(:active, [true, false], :to_s, :to_s) do |b|
+        b.label { b.radio_button + b.text }
+      end
+      concat rendered_radio_buttons
+      concat f.hidden_field :id
+    end
+
+    expected = whole_form("/posts") do
+      "<input type='hidden' name='post[active]' value='' />" \
+      "<label for='post_active_true'>" \
+      "<input name='post[active]' type='radio' value='true' id='post_active_true' />" \
+      "true</label>" \
+      "<label for='post_active_false'>" \
+      "<input checked='checked' name='post[active]' type='radio' value='false' id='post_active_false' />" \
+      "false</label>" \
+      "<input name='post[id]' type='hidden' value='1' id='post_id' />"
+    end
+
+    assert_dom_equal expected, output_buffer
+  end
+
+  def test_form_with_with_index_and_with_collection_radio_buttons
+    post = Post.new
+    def post.active; false; end
+
+    form_with(model: post, index: "1") do |f|
+      concat f.collection_radio_buttons(:active, [true, false], :to_s, :to_s)
+    end
+
+    expected = whole_form("/posts") do
+      "<input type='hidden' name='post[1][active]' value='' />" \
+      "<input name='post[1][active]' type='radio' value='true' id='post_1_active_true' />" \
+      "<label for='post_1_active_true'>true</label>" \
+      "<input checked='checked' name='post[1][active]' type='radio' value='false' id='post_1_active_false' />" \
+      "<label for='post_1_active_false'>false</label>"
+    end
+
+    assert_dom_equal expected, output_buffer
+  end
+
+  def test_form_with_with_collection_check_boxes
+    post = Post.new
+    def post.tag_ids; [1, 3]; end
+    collection = (1..3).map { |i| [i, "Tag #{i}"] }
+    form_with(model: post) do |f|
+      concat f.collection_check_boxes(:tag_ids, collection, :first, :last)
+    end
+
+    expected = whole_form("/posts") do
+      "<input name='post[tag_ids][]' type='hidden' value='' />" \
+      "<input checked='checked' name='post[tag_ids][]' type='checkbox' value='1' id='post_tag_ids_1' />" \
+      "<label for='post_tag_ids_1'>Tag 1</label>" \
+      "<input name='post[tag_ids][]' type='checkbox' value='2' id='post_tag_ids_2' />" \
+      "<label for='post_tag_ids_2'>Tag 2</label>" \
+      "<input checked='checked' name='post[tag_ids][]' type='checkbox' value='3' id='post_tag_ids_3' />" \
+      "<label for='post_tag_ids_3'>Tag 3</label>"
+    end
+
+    assert_dom_equal expected, output_buffer
+  end
+
+  def test_form_with_with_collection_check_boxes_with_custom_builder_block
+    post = Post.new
+    def post.tag_ids; [1, 3]; end
+    collection = (1..3).map { |i| [i, "Tag #{i}"] }
+    form_with(model: post) do |f|
+      rendered_check_boxes = f.collection_check_boxes(:tag_ids, collection, :first, :last) do |b|
+        b.label { b.check_box + b.text }
+      end
+      concat rendered_check_boxes
+    end
+
+    expected = whole_form("/posts") do
+      "<input name='post[tag_ids][]' type='hidden' value='' />" \
+      "<label for='post_tag_ids_1'>" \
+      "<input checked='checked' name='post[tag_ids][]' type='checkbox' value='1' id='post_tag_ids_1' />" \
+      "Tag 1</label>" \
+      "<label for='post_tag_ids_2'>" \
+      "<input name='post[tag_ids][]' type='checkbox' value='2' id='post_tag_ids_2' />" \
+      "Tag 2</label>" \
+      "<label for='post_tag_ids_3'>" \
+      "<input checked='checked' name='post[tag_ids][]' type='checkbox' value='3' id='post_tag_ids_3' />" \
+      "Tag 3</label>"
+    end
+
+    assert_dom_equal expected, output_buffer
+  end
+
+  def test_form_with_with_collection_check_boxes_with_custom_builder_block_does_not_leak_the_template
+    post = Post.new
+    def post.tag_ids; [1, 3]; end
+    def post.id; 1; end
+    collection = (1..3).map { |i| [i, "Tag #{i}"] }
+
+    form_with(model: post) do |f|
+      rendered_check_boxes = f.collection_check_boxes(:tag_ids, collection, :first, :last) do |b|
+        b.label { b.check_box + b.text }
+      end
+      concat rendered_check_boxes
+      concat f.hidden_field :id
+    end
+
+    expected = whole_form("/posts") do
+      "<input name='post[tag_ids][]' type='hidden' value='' />" \
+      "<label for='post_tag_ids_1'>" \
+      "<input checked='checked' name='post[tag_ids][]' type='checkbox' value='1' id='post_tag_ids_1' />" \
+      "Tag 1</label>" \
+      "<label for='post_tag_ids_2'>" \
+      "<input name='post[tag_ids][]' type='checkbox' value='2' id='post_tag_ids_2' />" \
+      "Tag 2</label>" \
+      "<label for='post_tag_ids_3'>" \
+      "<input checked='checked' name='post[tag_ids][]' type='checkbox' value='3' id='post_tag_ids_3' />" \
+      "Tag 3</label>" \
+      "<input name='post[id]' type='hidden' value='1' id='post_id' />"
+    end
+
+    assert_dom_equal expected, output_buffer
+  end
+
+  def test_form_with_index_and_with_collection_check_boxes
+    post = Post.new
+    def post.tag_ids; [1]; end
+    collection = [[1, "Tag 1"]]
+
+    form_with(model: post, index: "1") do |f|
+      concat f.collection_check_boxes(:tag_ids, collection, :first, :last)
+    end
+
+    expected = whole_form("/posts") do
+      "<input name='post[1][tag_ids][]' type='hidden' value='' />" \
+      "<input checked='checked' name='post[1][tag_ids][]' type='checkbox' value='1' id='post_1_tag_ids_1' />" \
+      "<label for='post_1_tag_ids_1'>Tag 1</label>"
+    end
+
+    assert_dom_equal expected, output_buffer
+  end
+
+  def test_form_with_with_file_field_generate_multipart
+    form_with(model: @post, id: "create-post") do |f|
+      concat f.file_field(:file)
+    end
+
+    expected = whole_form("/posts/123", "create-post", method: "patch", multipart: true) do
+      "<input name='post[file]' type='file' id='post_file' />"
+    end
+
+    assert_dom_equal expected, output_buffer
+  end
+
+  def test_fields_with_file_field_generate_multipart
+    form_with(model: @post) do |f|
+      concat f.fields(:comment, model: @post) { |c|
+        concat c.file_field(:file)
+      }
+    end
+
+    expected = whole_form("/posts/123", method: "patch", multipart: true) do
+      "<input name='post[comment][file]' type='file' id='post_comment_file'/>"
+    end
+
+    assert_dom_equal expected, output_buffer
+  end
+
+  def test_form_with_with_format
+    form_with(model: @post, format: :json, id: "edit_post_123", class: "edit_post") do |f|
+      concat f.label(:title)
+    end
+
+    expected = whole_form("/posts/123.json", "edit_post_123", "edit_post", method: "patch") do
+      "<label for='post_title'>Title</label>"
+    end
+
+    assert_dom_equal expected, output_buffer
+  end
+
+  def test_form_with_with_format_and_url
+    form_with(model: @post, format: :json, url: "/") do |f|
+      concat f.label(:title)
+    end
+
+    expected = whole_form("/", method: "patch") do
+      "<label for='post_title'>Title</label>"
+    end
+
+    assert_dom_equal expected, output_buffer
+  end
+
+  def test_form_with_with_model_using_relative_model_naming
+    blog_post = Blog::Post.new("And his name will be forty and four.", 44)
+
+    form_with(model: blog_post) do |f|
+      concat f.text_field :title
+      concat f.submit("Edit post")
+    end
+
+    expected = whole_form("/posts/44", method: "patch") do
+      "<input name='post[title]' type='text' value='And his name will be forty and four.' id='post_title' />" \
+      "<input name='commit' data-disable-with='Edit post' type='submit' value='Edit post' />"
+    end
+
+    assert_dom_equal expected, output_buffer
+  end
+
+  def test_form_with_with_symbol_scope
+    form_with(model: @post, scope: "other_name", id: "create-post") do |f|
+      concat f.label(:title, class: "post_title")
+      concat f.text_field(:title)
+      concat f.text_area(:body)
+      concat f.check_box(:secret)
+      concat f.submit("Create post")
+    end
+
+    expected = whole_form("/posts/123", "create-post", method: "patch") do
+      "<label for='other_name_title' class='post_title'>Title</label>" \
+      "<input name='other_name[title]' value='Hello World' type='text' id='other_name_title' />" \
+      "<textarea name='other_name[body]' id='other_name_body'>\nBack to the hill and over it again!</textarea>" \
+      "<input name='other_name[secret]' value='0' type='hidden' />" \
+      "<input name='other_name[secret]' checked='checked' value='1' type='checkbox' id='other_name_secret' />" \
+      "<input name='commit' value='Create post' data-disable-with='Create post' type='submit' />"
+    end
+
+    assert_dom_equal expected, output_buffer
+  end
+
+  def test_form_with_with_method_as_part_of_html_options
+    form_with(model: @post, url: "/", id: "create-post", html: { method: :delete }) do |f|
+      concat f.text_field(:title)
+      concat f.text_area(:body)
+      concat f.check_box(:secret)
+    end
+
+    expected = whole_form("/", "create-post", method: "delete") do
+      "<input name='post[title]' type='text' value='Hello World' id='post_title' />" \
+      "<textarea name='post[body]' id='post_body'>\nBack to the hill and over it again!</textarea>" \
+      "<input name='post[secret]' type='hidden' value='0' />" \
+      "<input name='post[secret]' checked='checked' type='checkbox' value='1' id='post_secret'/>"
+    end
+
+    assert_dom_equal expected, output_buffer
+  end
+
+  def test_form_with_with_method
+    form_with(model: @post, url: "/", method: :delete, id: "create-post") do |f|
+      concat f.text_field(:title)
+      concat f.text_area(:body)
+      concat f.check_box(:secret)
+    end
+
+    expected = whole_form("/", "create-post", method: "delete") do
+      "<input name='post[title]' type='text' value='Hello World' id='post_title' />" \
+      "<textarea name='post[body]' id='post_body' >\nBack to the hill and over it again!</textarea>" \
+      "<input name='post[secret]' type='hidden' value='0' />" \
+      "<input name='post[secret]' checked='checked' type='checkbox' value='1' id='post_secret' />"
+    end
+
+    assert_dom_equal expected, output_buffer
+  end
+
+  def test_form_with_with_search_field
+    # Test case for bug which would emit an "object" attribute
+    # when used with form_for using a search_field form helper
+    form_with(model: Post.new, url: "/search", id: "search-post", method: :get) do |f|
+      concat f.search_field(:title)
+    end
+
+    expected = whole_form("/search", "search-post", method: "get") do
+      "<input name='post[title]' type='search' id='post_title' />"
+    end
+
+    assert_dom_equal expected, output_buffer
+  end
+
+  def test_form_with_enables_remote_by_default
+    form_with(model: @post, url: "/", id: "create-post", method: :patch) do |f|
+      concat f.text_field(:title)
+      concat f.text_area(:body)
+      concat f.check_box(:secret)
+    end
+
+    expected = whole_form("/", "create-post", method: "patch") do
+      "<input name='post[title]' type='text' value='Hello World' id='post_title' />" \
+      "<textarea name='post[body]' id='post_body' >\nBack to the hill and over it again!</textarea>" \
+      "<input name='post[secret]' type='hidden' value='0' />" \
+      "<input name='post[secret]' checked='checked' type='checkbox' value='1' id='post_secret' />"
+    end
+
+    assert_dom_equal expected, output_buffer
+  end
+
+  def test_form_is_not_remote_by_default_if_form_with_generates_remote_forms_is_false
+    old_value = ActionView::Helpers::FormHelper.form_with_generates_remote_forms
+    ActionView::Helpers::FormHelper.form_with_generates_remote_forms = false
+
+    form_with(model: @post, url: "/", id: "create-post", method: :patch) do |f|
+      concat f.text_field(:title)
+      concat f.text_area(:body)
+      concat f.check_box(:secret)
+    end
+
+    expected = whole_form("/", "create-post", method: "patch", local: true) do
+      "<input name='post[title]' type='text' value='Hello World' id='post_title' />" \
+      "<textarea name='post[body]' id='post_body'>\nBack to the hill and over it again!</textarea>" \
+      "<input name='post[secret]' type='hidden' value='0' />" \
+      "<input name='post[secret]' checked='checked' type='checkbox' value='1' id='post_secret' />"
+    end
+
+    assert_dom_equal expected, output_buffer
+  ensure
+    ActionView::Helpers::FormHelper.form_with_generates_remote_forms = old_value
+  end
+
+  def test_form_with_skip_enforcing_utf8_true
+    form_with(scope: :post, skip_enforcing_utf8: true) do |f|
+      concat f.text_field(:title)
+    end
+
+    expected = whole_form("/", skip_enforcing_utf8: true) do
+      "<input name='post[title]' type='text' value='Hello World' id='post_title' />"
+    end
+
+    assert_dom_equal expected, output_buffer
+  end
+
+  def test_form_with_skip_enforcing_utf8_false
+    form_with(scope: :post, skip_enforcing_utf8: false) do |f|
+      concat f.text_field(:title)
+    end
+
+    expected = whole_form("/", skip_enforcing_utf8: false) do
+      "<input name='post[title]' type='text' value='Hello World' id='post_title' />"
+    end
+
+    assert_dom_equal expected, output_buffer
+  end
+
+  def test_form_with_without_object
+    form_with(scope: :post, id: "create-post") do |f|
+      concat f.text_field(:title)
+      concat f.text_area(:body)
+      concat f.check_box(:secret)
+    end
+
+    expected = whole_form("/", "create-post") do
+      "<input name='post[title]' type='text' value='Hello World' id='post_title' />" \
+      "<textarea name='post[body]' id='post_body' >\nBack to the hill and over it again!</textarea>" \
+      "<input name='post[secret]' type='hidden' value='0' />" \
+      "<input name='post[secret]' checked='checked' type='checkbox' value='1' id='post_secret' />"
+    end
+
+    assert_dom_equal expected, output_buffer
+  end
+
+  def test_form_with_with_index
+    form_with(model: @post, scope: "post[]") do |f|
+      concat f.label(:title)
+      concat f.text_field(:title)
+      concat f.text_area(:body)
+      concat f.check_box(:secret)
+    end
+
+    expected = whole_form("/posts/123", method: "patch") do
+      "<label for='post_123_title'>Title</label>" \
+      "<input name='post[123][title]' type='text' value='Hello World' id='post_123_title' />" \
+      "<textarea name='post[123][body]' id='post_123_body'>\nBack to the hill and over it again!</textarea>" \
+      "<input name='post[123][secret]' type='hidden' value='0' />" \
+      "<input name='post[123][secret]' checked='checked' type='checkbox' value='1' id='post_123_secret' />"
+    end
+
+    assert_dom_equal expected, output_buffer
+  end
+
+  def test_form_with_with_nil_index_option_override
+    form_with(model: @post, scope: "post[]", index: nil) do |f|
+      concat f.text_field(:title)
+      concat f.text_area(:body)
+      concat f.check_box(:secret)
+    end
+
+    expected = whole_form("/posts/123", method: "patch") do
+      "<input name='post[][title]' type='text' value='Hello World' id='post__title' />" \
+      "<textarea name='post[][body]' id='post__body' >\nBack to the hill and over it again!</textarea>" \
+      "<input name='post[][secret]' type='hidden' value='0' />" \
+      "<input name='post[][secret]' checked='checked' type='checkbox' value='1' id='post__secret' />"
+    end
+
+    assert_dom_equal expected, output_buffer
+  end
+
+  def test_form_with_label_error_wrapping
+    form_with(model: @post) do |f|
+      concat f.label(:author_name, class: "label")
+      concat f.text_field(:author_name)
+      concat f.submit("Create post")
+    end
+
+    expected = whole_form("/posts/123", method: "patch") do
+      "<div class='field_with_errors'><label for='post_author_name' class='label'>Author name</label></div>" \
+      "<div class='field_with_errors'><input name='post[author_name]' type='text' value='' id='post_author_name' /></div>" \
+      "<input name='commit' data-disable-with='Create post' type='submit' value='Create post' />"
+    end
+
+    assert_dom_equal expected, output_buffer
+  end
+
+  def test_form_with_label_error_wrapping_without_conventional_instance_variable
+    post = remove_instance_variable :@post
+
+    form_with(model: post) do |f|
+      concat f.label(:author_name, class: "label")
+      concat f.text_field(:author_name)
+      concat f.submit("Create post")
+    end
+
+    expected = whole_form("/posts/123", method: "patch") do
+      "<div class='field_with_errors'><label for='post_author_name' class='label'>Author name</label></div>" \
+      "<div class='field_with_errors'><input name='post[author_name]' type='text' value='' id='post_author_name' /></div>" \
+      "<input name='commit' data-disable-with='Create post' type='submit' value='Create post' />"
+    end
+
+    assert_dom_equal expected, output_buffer
+  end
+
+  def test_form_with_label_error_wrapping_block_and_non_block_versions
+    form_with(model: @post) do |f|
+      concat f.label(:author_name, "Name", class: "label")
+      concat f.label(:author_name, class: "label") { "Name" }
+    end
+
+    expected = whole_form("/posts/123", method: "patch") do
+      "<div class='field_with_errors'><label for='post_author_name' class='label'>Name</label></div>" \
+      "<div class='field_with_errors'><label for='post_author_name' class='label'>Name</label></div>"
+    end
+
+    assert_dom_equal expected, output_buffer
+  end
+
+  def test_submit_with_object_as_new_record_and_locale_strings
+    with_locale :submit do
+      @post.persisted = false
+      @post.stub(:to_key, nil) do
+        form_with(model: @post) do |f|
+          concat f.submit
+        end
+
+        expected = whole_form("/posts") do
+          "<input name='commit' data-disable-with='Create Post' type='submit' value='Create Post' />"
+        end
+
+        assert_dom_equal expected, output_buffer
+      end
+    end
+  end
+
+  def test_submit_with_object_as_existing_record_and_locale_strings
+    with_locale :submit do
+      form_with(model: @post) do |f|
+        concat f.submit
+      end
+
+      expected = whole_form("/posts/123", method: "patch") do
+        "<input name='commit' data-disable-with='Confirm Post changes' type='submit' value='Confirm Post changes' />"
+      end
+
+      assert_dom_equal expected, output_buffer
+    end
+  end
+
+  def test_submit_without_object_and_locale_strings
+    with_locale :submit do
+      form_with(scope: :post) do |f|
+        concat f.submit class: "extra"
+      end
+
+      expected = whole_form do
+        "<input name='commit' class='extra' data-disable-with='Save changes' type='submit' value='Save changes' />"
+      end
+
+      assert_dom_equal expected, output_buffer
+    end
+  end
+
+  def test_submit_with_object_and_nested_lookup
+    with_locale :submit do
+      form_with(model: @post, scope: :another_post) do |f|
+        concat f.submit
+      end
+
+      expected = whole_form("/posts/123", method: "patch") do
+        "<input name='commit' data-disable-with='Update your Post' type='submit' value='Update your Post' />"
+      end
+
+      assert_dom_equal expected, output_buffer
+    end
+  end
+
+  def test_fields_with_attributes_not_on_model
+    form_with(model: @post) do |f|
+      concat f.fields(:comment) { |c|
+        concat c.text_field :dont_exist_on_model
+      }
+    end
+
+    expected = whole_form("/posts/123", method: :patch) do
+      '<input type="text" name="post[comment][dont_exist_on_model]" id="post_comment_dont_exist_on_model" >'
+    end
+
+    assert_dom_equal expected, output_buffer
+  end
+
+  def test_fields_with_attributes_not_on_model_deep_nested
+    @comment.save
+    form_with(scope: :posts) do |f|
+      f.fields("post[]", model: @post) do |f2|
+        f2.text_field(:id)
+        @post.comments.each do |comment|
+          concat f2.fields("comment[]", model: comment) { |c|
+            concat c.text_field(:dont_exist_on_model)
+          }
+        end
+      end
+    end
+
+    expected = whole_form do
+      '<input name="posts[post][0][comment][1][dont_exist_on_model]" type="text" id="posts_post_0_comment_1_dont_exist_on_model" >'
+    end
+
+    assert_dom_equal expected, output_buffer
+  end
+
+  def test_nested_fields
+    @comment.body = "Hello World"
+    form_with(model: @post) do |f|
+      concat f.fields(model: @comment) { |c|
+        concat c.text_field(:body)
+      }
+    end
+
+    expected = whole_form("/posts/123", method: "patch") do
+      "<input name='post[comment][body]' type='text' value='Hello World' id='post_comment_body' />"
+    end
+
+    assert_dom_equal expected, output_buffer
+  end
+
+  def test_deep_nested_fields
+    @comment.save
+    form_with(scope: :posts) do |f|
+      f.fields("post[]", model: @post) do |f2|
+        f2.text_field(:id)
+        @post.comments.each do |comment|
+          concat f2.fields("comment[]", model: comment) { |c|
+            concat c.text_field(:name)
+          }
+        end
+      end
+    end
+
+    expected = whole_form do
+      "<input name='posts[post][0][comment][1][name]' type='text' value='comment #1' id='posts_post_0_comment_1_name' />"
+    end
+
+    assert_dom_equal expected, output_buffer
+  end
+
+  def test_nested_fields_with_nested_collections
+    form_with(model: @post, scope: "post[]") do |f|
+      concat f.text_field(:title)
+      concat f.fields("comment[]", model: @comment) { |c|
+        concat c.text_field(:name)
+      }
+    end
+
+    expected = whole_form("/posts/123", method: "patch") do
+      "<input name='post[123][title]' type='text' value='Hello World' id='post_123_title' />" \
+      "<input name='post[123][comment][][name]' type='text' value='new comment' id='post_123_comment__name' />"
+    end
+
+    assert_dom_equal expected, output_buffer
+  end
+
+  def test_nested_fields_with_index_and_parent_fields
+    form_with(model: @post, index: 1) do |c|
+      concat c.text_field(:title)
+      concat c.fields("comment", model: @comment, index: 1) { |r|
+        concat r.text_field(:name)
+      }
+    end
+
+    expected = whole_form("/posts/123", method: "patch") do
+      "<input name='post[1][title]' type='text' value='Hello World' id='post_1_title' />" \
+      "<input name='post[1][comment][1][name]' type='text' value='new comment' id='post_1_comment_1_name' />"
+    end
+
+    assert_dom_equal expected, output_buffer
+  end
+
+  def test_form_with_with_index_and_nested_fields
+    output_buffer = form_with(model: @post, index: 1) do |f|
+      concat f.fields(:comment, model: @post) { |c|
+        concat c.text_field(:title)
+      }
+    end
+
+    expected = whole_form("/posts/123", method: "patch") do
+      "<input name='post[1][comment][title]' type='text' value='Hello World' id='post_1_comment_title' />"
+    end
+
+    assert_dom_equal expected, output_buffer
+  end
+
+  def test_nested_fields_with_index_on_both
+    form_with(model: @post, index: 1) do |f|
+      concat f.fields(:comment, model: @post, index: 5) { |c|
+        concat c.text_field(:title)
+      }
+    end
+
+    expected = whole_form("/posts/123", method: "patch") do
+      "<input name='post[1][comment][5][title]' type='text' value='Hello World' id='post_1_comment_5_title' />"
+    end
+
+    assert_dom_equal expected, output_buffer
+  end
+
+  def test_nested_fields_with_auto_index
+    form_with(model: @post, scope: "post[]") do |f|
+      concat f.fields(:comment, model: @post) { |c|
+        concat c.text_field(:title)
+      }
+    end
+
+    expected = whole_form("/posts/123", method: "patch") do
+      "<input name='post[123][comment][title]' type='text' value='Hello World' id='post_123_comment_title' />"
+    end
+
+    assert_dom_equal expected, output_buffer
+  end
+
+  def test_nested_fields_with_index_radio_button
+    form_with(model: @post) do |f|
+      concat f.fields(:comment, model: @post, index: 5) { |c|
+        concat c.radio_button(:title, "hello")
+      }
+    end
+
+    expected = whole_form("/posts/123", method: "patch") do
+      "<input name='post[comment][5][title]' type='radio' value='hello' id='post_comment_5_title_hello' />"
+    end
+
+    assert_dom_equal expected, output_buffer
+  end
+
+  def test_nested_fields_with_auto_index_on_both
+    form_with(model: @post, scope: "post[]") do |f|
+      concat f.fields("comment[]", model: @post) { |c|
+        concat c.text_field(:title)
+      }
+    end
+
+    expected = whole_form("/posts/123", method: "patch") do
+      "<input name='post[123][comment][123][title]' type='text' value='Hello World' id='post_123_comment_123_title' />"
+    end
+
+    assert_dom_equal expected, output_buffer
+  end
+
+  def test_nested_fields_with_index_and_auto_index
+    output_buffer = form_with(model: @post, scope: "post[]") do |f|
+      concat f.fields(:comment, model: @post, index: 5) { |c|
+        concat c.text_field(:title)
+      }
+    end
+
+    output_buffer << form_with(model: @post, index: 1) do |f|
+      concat f.fields("comment[]", model: @post) { |c|
+        concat c.text_field(:title)
+      }
+    end
+
+    expected = whole_form("/posts/123", method: "patch") do
+      "<input name='post[123][comment][5][title]' type='text' value='Hello World' id='post_123_comment_5_title' />"
+    end + whole_form("/posts/123", method: "patch") do
+      "<input name='post[1][comment][123][title]' type='text' value='Hello World' id='post_1_comment_123_title' />"
+    end
+
+    assert_dom_equal expected, output_buffer
+  end
+
+  def test_nested_fields_with_a_new_record_on_a_nested_attributes_one_to_one_association
+    @post.author = Author.new
+
+    form_with(model: @post) do |f|
+      concat f.text_field(:title)
+      concat f.fields(:author) { |af|
+        concat af.text_field(:name)
+      }
+    end
+
+    expected = whole_form("/posts/123", method: "patch") do
+      '<input name="post[title]" type="text" value="Hello World" id="post_title" />' \
+        '<input name="post[author_attributes][name]" type="text" value="new author" id="post_author_attributes_name" />'
+    end
+
+    assert_dom_equal expected, output_buffer
+  end
+
+  def test_nested_fields_with_explicitly_passed_object_on_a_nested_attributes_one_to_one_association
+    form_with(model: @post) do |f|
+      f.fields(:author, model: Author.new(123)) do |af|
+        assert_not_nil af.object
+        assert_equal 123, af.object.id
+      end
+    end
+  end
+
+  def test_nested_fields_with_an_existing_record_on_a_nested_attributes_one_to_one_association
+    @post.author = Author.new(321)
+
+    form_with(model: @post) do |f|
+      concat f.text_field(:title)
+      concat f.fields(:author) { |af|
+        concat af.text_field(:name)
+      }
+    end
+
+    expected = whole_form("/posts/123", method: "patch") do
+      '<input name="post[title]" type="text" value="Hello World" id="post_title" />' \
+      '<input name="post[author_attributes][name]" type="text" value="author #321" id="post_author_attributes_name" />' \
+      '<input name="post[author_attributes][id]" type="hidden" value="321" id="post_author_attributes_id" />'
+    end
+
+    assert_dom_equal expected, output_buffer
+  end
+
+  def test_nested_fields_with_an_existing_record_on_a_nested_attributes_one_to_one_association_using_erb_and_inline_block
+    @post.author = Author.new(321)
+
+    form_with(model: @post) do |f|
+      concat f.text_field(:title)
+      concat f.fields(:author) { |af|
+        af.text_field(:name)
+      }
+    end
+
+    expected = whole_form("/posts/123", method: "patch") do
+      '<input name="post[title]" type="text" value="Hello World" id="post_title" />' \
+      '<input name="post[author_attributes][name]" type="text" value="author #321" id="post_author_attributes_name" />' \
+      '<input name="post[author_attributes][id]" type="hidden" value="321" id="post_author_attributes_id" />'
+    end
+
+    assert_dom_equal expected, output_buffer
+  end
+
+  def test_nested_fields_with_an_existing_record_on_a_nested_attributes_one_to_one_association_with_disabled_hidden_id
+    @post.author = Author.new(321)
+
+    form_with(model: @post) do |f|
+      concat f.text_field(:title)
+      concat f.fields(:author, skip_id: true) { |af|
+        af.text_field(:name)
+      }
+    end
+
+    expected = whole_form("/posts/123", method: "patch") do
+      '<input name="post[title]" type="text" value="Hello World" id="post_title" />' \
+      '<input name="post[author_attributes][name]" type="text" value="author #321" id="post_author_attributes_name" />'
+    end
+
+    assert_dom_equal expected, output_buffer
+  end
+
+  def test_nested_fields_with_an_existing_record_on_a_nested_attributes_one_to_one_association_with_disabled_hidden_id_inherited
+    @post.author = Author.new(321)
+
+    form_with(model: @post, skip_id: true) do |f|
+      concat f.text_field(:title)
+      concat f.fields(:author) { |af|
+        af.text_field(:name)
+      }
+    end
+
+    expected = whole_form("/posts/123", method: "patch") do
+      '<input name="post[title]" type="text" value="Hello World" id="post_title" />' \
+      '<input name="post[author_attributes][name]" type="text" value="author #321" id="post_author_attributes_name" />'
+    end
+
+    assert_dom_equal expected, output_buffer
+  end
+
+  def test_nested_fields_with_an_existing_record_on_a_nested_attributes_one_to_one_association_with_disabled_hidden_id_override
+    @post.author = Author.new(321)
+
+    form_with(model: @post, skip_id: true) do |f|
+      concat f.text_field(:title)
+      concat f.fields(:author, skip_id: false) { |af|
+        af.text_field(:name)
+      }
+    end
+
+    expected = whole_form("/posts/123", method: "patch") do
+      '<input name="post[title]" type="text" value="Hello World" id="post_title" />' \
+      '<input name="post[author_attributes][name]" type="text" value="author #321" id="post_author_attributes_name" />' \
+      '<input name="post[author_attributes][id]" type="hidden" value="321" id="post_author_attributes_id" />'
+    end
+
+    assert_dom_equal expected, output_buffer
+  end
+
+  def test_nested_fields_with_existing_records_on_a_nested_attributes_one_to_one_association_with_explicit_hidden_field_placement
+    @post.author = Author.new(321)
+
+    form_with(model: @post) do |f|
+      concat f.text_field(:title)
+      concat f.fields(:author) { |af|
+        concat af.hidden_field(:id)
+        concat af.text_field(:name)
+      }
+    end
+
+    expected = whole_form("/posts/123", method: "patch") do
+      '<input name="post[title]" type="text" value="Hello World" id="post_title" />' \
+      '<input name="post[author_attributes][id]" type="hidden" value="321" id="post_author_attributes_id" />' \
+      '<input name="post[author_attributes][name]" type="text" value="author #321" id="post_author_attributes_name" />'
+    end
+
+    assert_dom_equal expected, output_buffer
+  end
+
+  def test_nested_fields_with_existing_records_on_a_nested_attributes_collection_association
+    @post.comments = Array.new(2) { |id| Comment.new(id + 1) }
+
+    form_with(model: @post) do |f|
+      concat f.text_field(:title)
+      @post.comments.each do |comment|
+        concat f.fields(:comments, model: comment) { |cf|
+          concat cf.text_field(:name)
+        }
+      end
+    end
+
+    expected = whole_form("/posts/123", method: "patch") do
+      '<input name="post[title]" type="text" value="Hello World" id="post_title" />' \
+      '<input name="post[comments_attributes][0][name]" type="text" value="comment #1" id="post_comments_attributes_0_name" />' \
+      '<input name="post[comments_attributes][0][id]" type="hidden" value="1" id="post_comments_attributes_0_id" />' \
+      '<input name="post[comments_attributes][1][name]" type="text" value="comment #2" id="post_comments_attributes_1_name" />' \
+      '<input name="post[comments_attributes][1][id]" type="hidden" value="2" id="post_comments_attributes_1_id" />'
+    end
+
+    assert_dom_equal expected, output_buffer
+  end
+
+  def test_nested_fields_with_existing_records_on_a_nested_attributes_collection_association_with_disabled_hidden_id
+    @post.comments = Array.new(2) { |id| Comment.new(id + 1) }
+    @post.author = Author.new(321)
+
+    form_with(model: @post) do |f|
+      concat f.text_field(:title)
+      concat f.fields(:author) { |af|
+        concat af.text_field(:name)
+      }
+      @post.comments.each do |comment|
+        concat f.fields(:comments, model: comment, skip_id: true) { |cf|
+          concat cf.text_field(:name)
+        }
+      end
+    end
+
+    expected = whole_form("/posts/123", method: "patch") do
+      '<input name="post[title]" type="text" value="Hello World" id="post_title" />' \
+      '<input name="post[author_attributes][name]" type="text" value="author #321" id="post_author_attributes_name" />' \
+      '<input name="post[author_attributes][id]" type="hidden" value="321" id="post_author_attributes_id" />' \
+      '<input name="post[comments_attributes][0][name]" type="text" value="comment #1" id="post_comments_attributes_0_name" />' \
+      '<input name="post[comments_attributes][1][name]" type="text" value="comment #2" id="post_comments_attributes_1_name" />'
+    end
+
+    assert_dom_equal expected, output_buffer
+  end
+
+  def test_nested_fields_with_existing_records_on_a_nested_attributes_collection_association_with_disabled_hidden_id_inherited
+    @post.comments = Array.new(2) { |id| Comment.new(id + 1) }
+    @post.author = Author.new(321)
+
+    form_with(model: @post, skip_id: true) do |f|
+      concat f.text_field(:title)
+      concat f.fields(:author) { |af|
+        concat af.text_field(:name)
+      }
+      @post.comments.each do |comment|
+        concat f.fields(:comments, model: comment) { |cf|
+          concat cf.text_field(:name)
+        }
+      end
+    end
+
+    expected = whole_form("/posts/123", method: "patch") do
+      '<input name="post[title]" type="text" value="Hello World" id="post_title" />' \
+      '<input name="post[author_attributes][name]" type="text" value="author #321" id="post_author_attributes_name" />' \
+      '<input name="post[comments_attributes][0][name]" type="text" value="comment #1" id="post_comments_attributes_0_name" />' \
+      '<input name="post[comments_attributes][1][name]" type="text" value="comment #2" id="post_comments_attributes_1_name" />'
+    end
+
+    assert_dom_equal expected, output_buffer
+  end
+
+  def test_nested_fields_with_existing_records_on_a_nested_attributes_collection_association_with_disabled_hidden_id_override
+    @post.comments = Array.new(2) { |id| Comment.new(id + 1) }
+    @post.author = Author.new(321)
+
+    form_with(model: @post, skip_id: true) do |f|
+      concat f.text_field(:title)
+      concat f.fields(:author, skip_id: false) { |af|
+        concat af.text_field(:name)
+      }
+      @post.comments.each do |comment|
+        concat f.fields(:comments, model: comment) { |cf|
+          concat cf.text_field(:name)
+        }
+      end
+    end
+
+    expected = whole_form("/posts/123", method: "patch") do
+      '<input name="post[title]" type="text" value="Hello World" id="post_title" />' \
+      '<input name="post[author_attributes][name]" type="text" value="author #321" id="post_author_attributes_name" />' \
+      '<input name="post[author_attributes][id]" type="hidden" value="321" id="post_author_attributes_id" />' \
+      '<input name="post[comments_attributes][0][name]" type="text" value="comment #1" id="post_comments_attributes_0_name" />' \
+      '<input name="post[comments_attributes][1][name]" type="text" value="comment #2" id="post_comments_attributes_1_name" />'
+    end
+
+    assert_dom_equal expected, output_buffer
+  end
+
+  def test_nested_fields_with_existing_records_on_a_nested_attributes_collection_association_using_erb_and_inline_block
+    @post.comments = Array.new(2) { |id| Comment.new(id + 1) }
+
+    form_with(model: @post) do |f|
+      concat f.text_field(:title)
+      @post.comments.each do |comment|
+        concat f.fields(:comments, model: comment) { |cf|
+          cf.text_field(:name)
+        }
+      end
+    end
+
+    expected = whole_form("/posts/123", method: "patch") do
+      '<input name="post[title]" type="text" value="Hello World" id="post_title" />' \
+      '<input name="post[comments_attributes][0][name]" type="text" value="comment #1" id="post_comments_attributes_0_name" />' \
+      '<input name="post[comments_attributes][0][id]" type="hidden" value="1" id="post_comments_attributes_0_id" />' \
+      '<input name="post[comments_attributes][1][name]" type="text" value="comment #2" id="post_comments_attributes_1_name" />' \
+      '<input name="post[comments_attributes][1][id]" type="hidden" value="2" id="post_comments_attributes_1_id" />'
+    end
+
+    assert_dom_equal expected, output_buffer
+  end
+
+  def test_nested_fields_with_existing_records_on_a_nested_attributes_collection_association_with_explicit_hidden_field_placement
+    @post.comments = Array.new(2) { |id| Comment.new(id + 1) }
+
+    form_with(model: @post) do |f|
+      concat f.text_field(:title)
+      @post.comments.each do |comment|
+        concat f.fields(:comments, model: comment) { |cf|
+          concat cf.hidden_field(:id)
+          concat cf.text_field(:name)
+        }
+      end
+    end
+
+    expected = whole_form("/posts/123", method: "patch") do
+      '<input name="post[title]" type="text" value="Hello World" id="post_title" />' \
+      '<input name="post[comments_attributes][0][id]" type="hidden" value="1" id="post_comments_attributes_0_id" />' \
+      '<input name="post[comments_attributes][0][name]" type="text" value="comment #1" id="post_comments_attributes_0_name" />' \
+      '<input name="post[comments_attributes][1][id]" type="hidden" value="2" id="post_comments_attributes_1_id" />' \
+      '<input name="post[comments_attributes][1][name]" type="text" value="comment #2" id="post_comments_attributes_1_name" />'
+    end
+
+    assert_dom_equal expected, output_buffer
+  end
+
+  def test_nested_fields_with_new_records_on_a_nested_attributes_collection_association
+    @post.comments = [Comment.new, Comment.new]
+
+    form_with(model: @post) do |f|
+      concat f.text_field(:title)
+      @post.comments.each do |comment|
+        concat f.fields(:comments, model: comment) { |cf|
+          concat cf.text_field(:name)
+        }
+      end
+    end
+
+    expected = whole_form("/posts/123", method: "patch") do
+      '<input name="post[title]" type="text" value="Hello World" id="post_title" />' \
+      '<input name="post[comments_attributes][0][name]" type="text" value="new comment" id="post_comments_attributes_0_name" />' \
+      '<input name="post[comments_attributes][1][name]" type="text" value="new comment" id="post_comments_attributes_1_name" />'
+    end
+
+    assert_dom_equal expected, output_buffer
+  end
+
+  def test_nested_fields_with_existing_and_new_records_on_a_nested_attributes_collection_association
+    @post.comments = [Comment.new(321), Comment.new]
+
+    form_with(model: @post) do |f|
+      concat f.text_field(:title)
+      @post.comments.each do |comment|
+        concat f.fields(:comments, model: comment) { |cf|
+          concat cf.text_field(:name)
+        }
+      end
+    end
+
+    expected = whole_form("/posts/123", method: "patch") do
+      '<input name="post[title]" type="text" value="Hello World" id="post_title" />' \
+      '<input name="post[comments_attributes][0][name]" type="text" value="comment #321" id="post_comments_attributes_0_name" />' \
+      '<input name="post[comments_attributes][0][id]" type="hidden" value="321" id="post_comments_attributes_0_id"/>' \
+      '<input name="post[comments_attributes][1][name]" type="text" value="new comment" id="post_comments_attributes_1_name" />'
+    end
+
+    assert_dom_equal expected, output_buffer
+  end
+
+  def test_nested_fields_with_an_empty_supplied_attributes_collection
+    form_with(model: @post) do |f|
+      concat f.text_field(:title)
+      f.fields(:comments, model: []) do |cf|
+        concat cf.text_field(:name)
+      end
+    end
+
+    expected = whole_form("/posts/123", method: "patch") do
+      '<input name="post[title]" type="text" value="Hello World" id="post_title" />'
+    end
+
+    assert_dom_equal expected, output_buffer
+  end
+
+  def test_nested_fields_with_existing_records_on_a_supplied_nested_attributes_collection
+    @post.comments = Array.new(2) { |id| Comment.new(id + 1) }
+
+    form_with(model: @post) do |f|
+      concat f.text_field(:title)
+      concat f.fields(:comments, model: @post.comments) { |cf|
+        concat cf.text_field(:name)
+      }
+    end
+
+    expected = whole_form("/posts/123", method: "patch") do
+      '<input name="post[title]" type="text" value="Hello World" id="post_title" />' \
+      '<input name="post[comments_attributes][0][name]" type="text" value="comment #1" id="post_comments_attributes_0_name" />' \
+      '<input name="post[comments_attributes][0][id]" type="hidden" value="1" id="post_comments_attributes_0_id" />' \
+      '<input name="post[comments_attributes][1][name]" type="text" value="comment #2" id="post_comments_attributes_1_name" />' \
+      '<input name="post[comments_attributes][1][id]" type="hidden" value="2" id="post_comments_attributes_1_id" />'
+    end
+
+    assert_dom_equal expected, output_buffer
+  end
+
+  def test_nested_fields_arel_like
+    @post.comments = ArelLike.new
+
+    form_with(model: @post) do |f|
+      concat f.text_field(:title)
+      concat f.fields(:comments, model: @post.comments) { |cf|
+        concat cf.text_field(:name)
+      }
+    end
+
+    expected = whole_form("/posts/123", method: "patch") do
+      '<input name="post[title]" type="text" value="Hello World" id="post_title" />' \
+      '<input name="post[comments_attributes][0][name]" type="text" value="comment #1" id="post_comments_attributes_0_name" />' \
+      '<input name="post[comments_attributes][0][id]" type="hidden" value="1" id="post_comments_attributes_0_id" />' \
+      '<input name="post[comments_attributes][1][name]" type="text" value="comment #2" id="post_comments_attributes_1_name" />' \
+      '<input name="post[comments_attributes][1][id]" type="hidden" value="2" id="post_comments_attributes_1_id" />'
+    end
+
+    assert_dom_equal expected, output_buffer
+  end
+
+  def test_nested_fields_label_translation_with_more_than_10_records
+    @post.comments = Array.new(11) { |id| Comment.new(id + 1) }
+
+    params = 11.times.map { ["post.comments.body", default: [:"comment.body", ""], scope: "helpers.label"] }
+    assert_called_with(I18n, :t, params, returns: "Write body here") do
+      form_with(model: @post) do |f|
+        f.fields(:comments) do |cf|
+          concat cf.label(:body)
+        end
+      end
+    end
+  end
+
+  def test_nested_fields_with_existing_records_on_a_supplied_nested_attributes_collection_different_from_record_one
+    comments = Array.new(2) { |id| Comment.new(id + 1) }
+    @post.comments = []
+
+    form_with(model: @post) do |f|
+      concat f.text_field(:title)
+      concat f.fields(:comments, model: comments) { |cf|
+        concat cf.text_field(:name)
+      }
+    end
+
+    expected = whole_form("/posts/123", method: "patch") do
+      '<input name="post[title]" type="text" value="Hello World" id="post_title" />' \
+      '<input name="post[comments_attributes][0][name]" type="text" value="comment #1" id="post_comments_attributes_0_name" />' \
+      '<input name="post[comments_attributes][0][id]" type="hidden" value="1" id="post_comments_attributes_0_id" />' \
+      '<input name="post[comments_attributes][1][name]" type="text" value="comment #2" id="post_comments_attributes_1_name" />' \
+      '<input name="post[comments_attributes][1][id]" type="hidden" value="2" id="post_comments_attributes_1_id" />'
+    end
+
+    assert_dom_equal expected, output_buffer
+  end
+
+  def test_nested_fields_on_a_nested_attributes_collection_association_yields_only_builder
+    @post.comments = [Comment.new(321), Comment.new]
+    yielded_comments = []
+
+    form_with(model: @post) do |f|
+      concat f.text_field(:title)
+      concat f.fields(:comments) { |cf|
+        concat cf.text_field(:name)
+        yielded_comments << cf.object
+      }
+    end
+
+    expected = whole_form("/posts/123", method: "patch") do
+      '<input name="post[title]" type="text" value="Hello World" id="post_title" />' \
+      '<input name="post[comments_attributes][0][name]" type="text" value="comment #321" id="post_comments_attributes_0_name" />' \
+      '<input name="post[comments_attributes][0][id]" type="hidden" value="321" id="post_comments_attributes_0_id" />' \
+      '<input name="post[comments_attributes][1][name]" type="text" value="new comment" id="post_comments_attributes_1_name" />'
+    end
+
+    assert_dom_equal expected, output_buffer
+    assert_equal yielded_comments, @post.comments
+  end
+
+  def test_nested_fields_with_child_index_option_override_on_a_nested_attributes_collection_association
+    @post.comments = []
+
+    form_with(model: @post) do |f|
+      concat f.fields(:comments, model: Comment.new(321), child_index: "abc") { |cf|
+        concat cf.text_field(:name)
+      }
+    end
+
+    expected = whole_form("/posts/123", method: "patch") do
+      '<input name="post[comments_attributes][abc][name]" type="text" value="comment #321" id="post_comments_attributes_abc_name" />' \
+      '<input name="post[comments_attributes][abc][id]" type="hidden" value="321" id="post_comments_attributes_abc_id" />'
+    end
+
+    assert_dom_equal expected, output_buffer
+  end
+
+  def test_nested_fields_with_child_index_as_lambda_option_override_on_a_nested_attributes_collection_association
+    @post.comments = []
+
+    form_with(model: @post) do |f|
+      concat f.fields(:comments, model: Comment.new(321), child_index: -> { "abc" }) { |cf|
+        concat cf.text_field(:name)
+      }
+    end
+
+    expected = whole_form("/posts/123", method: "patch") do
+      '<input name="post[comments_attributes][abc][name]" type="text" value="comment #321" id="post_comments_attributes_abc_name" />' \
+      '<input name="post[comments_attributes][abc][id]" type="hidden" value="321" id="post_comments_attributes_abc_id" />'
+    end
+
+    assert_dom_equal expected, output_buffer
+  end
+
+  class FakeAssociationProxy
+    def to_ary
+      [1, 2, 3]
+    end
+  end
+
+  def test_nested_fields_with_child_index_option_override_on_a_nested_attributes_collection_association_with_proxy
+    @post.comments = FakeAssociationProxy.new
+
+    form_with(model: @post) do |f|
+      concat f.fields(:comments, model: Comment.new(321), child_index: "abc") { |cf|
+        concat cf.text_field(:name)
+      }
+    end
+
+    expected = whole_form("/posts/123", method: "patch") do
+      '<input name="post[comments_attributes][abc][name]" type="text" value="comment #321" id="post_comments_attributes_abc_name" />' \
+      '<input name="post[comments_attributes][abc][id]" type="hidden" value="321" id="post_comments_attributes_abc_id" />'
+    end
+
+    assert_dom_equal expected, output_buffer
+  end
+
+  def test_nested_fields_index_method_with_existing_records_on_a_nested_attributes_collection_association
+    @post.comments = Array.new(2) { |id| Comment.new(id + 1) }
+
+    form_with(model: @post) do |f|
+      expected = 0
+      @post.comments.each do |comment|
+        f.fields(:comments, model: comment) { |cf|
+          assert_equal expected, cf.index
+          expected += 1
+        }
+      end
+    end
+  end
+
+  def test_nested_fields_index_method_with_existing_and_new_records_on_a_nested_attributes_collection_association
+    @post.comments = [Comment.new(321), Comment.new]
+
+    form_with(model: @post) do |f|
+      expected = 0
+      @post.comments.each do |comment|
+        f.fields(:comments, model: comment) { |cf|
+          assert_equal expected, cf.index
+          expected += 1
+        }
+      end
+    end
+  end
+
+  def test_nested_fields_index_method_with_existing_records_on_a_supplied_nested_attributes_collection
+    @post.comments = Array.new(2) { |id| Comment.new(id + 1) }
+
+    form_with(model: @post) do |f|
+      expected = 0
+      f.fields(:comments, model: @post.comments) { |cf|
+        assert_equal expected, cf.index
+        expected += 1
+      }
+    end
+  end
+
+  def test_nested_fields_index_method_with_child_index_option_override_on_a_nested_attributes_collection_association
+    @post.comments = []
+
+    form_with(model: @post) do |f|
+      f.fields(:comments, model: Comment.new(321), child_index: "abc") { |cf|
+        assert_equal "abc", cf.index
+      }
+    end
+  end
+
+  def test_nested_fields_uses_unique_indices_for_different_collection_associations
+    @post.comments = [Comment.new(321)]
+    @post.tags = [Tag.new(123), Tag.new(456)]
+    @post.comments[0].relevances = []
+    @post.tags[0].relevances = []
+    @post.tags[1].relevances = []
+
+    form_with(model: @post) do |f|
+      concat f.fields(:comments, model: @post.comments[0]) { |cf|
+        concat cf.text_field(:name)
+        concat cf.fields(:relevances, model: CommentRelevance.new(314)) { |crf|
+          concat crf.text_field(:value)
+        }
+      }
+      concat f.fields(:tags, model: @post.tags[0]) { |tf|
+        concat tf.text_field(:value)
+        concat tf.fields(:relevances, model: TagRelevance.new(3141)) { |trf|
+          concat trf.text_field(:value)
+        }
+      }
+      concat f.fields("tags", model: @post.tags[1]) { |tf|
+        concat tf.text_field(:value)
+        concat tf.fields(:relevances, model: TagRelevance.new(31415)) { |trf|
+          concat trf.text_field(:value)
+        }
+      }
+    end
+
+    expected = whole_form("/posts/123", method: "patch") do
+      '<input name="post[comments_attributes][0][name]" type="text" value="comment #321" id="post_comments_attributes_0_name" />' \
+      '<input name="post[comments_attributes][0][relevances_attributes][0][value]" type="text" value="commentrelevance #314" id="post_comments_attributes_0_relevances_attributes_0_value" />' \
+      '<input name="post[comments_attributes][0][relevances_attributes][0][id]" type="hidden" value="314" id="post_comments_attributes_0_relevances_attributes_0_id"/>' \
+      '<input name="post[comments_attributes][0][id]" type="hidden" value="321" id="post_comments_attributes_0_id"/>' \
+      '<input name="post[tags_attributes][0][value]" type="text" value="tag #123" id="post_tags_attributes_0_value"/>' \
+      '<input name="post[tags_attributes][0][relevances_attributes][0][value]" type="text" value="tagrelevance #3141" id="post_tags_attributes_0_relevances_attributes_0_value"/>' \
+      '<input name="post[tags_attributes][0][relevances_attributes][0][id]" type="hidden" value="3141" id="post_tags_attributes_0_relevances_attributes_0_id"/>' \
+      '<input name="post[tags_attributes][0][id]" type="hidden" value="123" id="post_tags_attributes_0_id"/>' \
+      '<input name="post[tags_attributes][1][value]" type="text" value="tag #456" id="post_tags_attributes_1_value"/>' \
+      '<input name="post[tags_attributes][1][relevances_attributes][0][value]" type="text" value="tagrelevance #31415" id="post_tags_attributes_1_relevances_attributes_0_value"/>' \
+      '<input name="post[tags_attributes][1][relevances_attributes][0][id]" type="hidden" value="31415" id="post_tags_attributes_1_relevances_attributes_0_id"/>' \
+      '<input name="post[tags_attributes][1][id]" type="hidden" value="456" id="post_tags_attributes_1_id"/>'
+    end
+
+    assert_dom_equal expected, output_buffer
+  end
+
+  def test_nested_fields_with_hash_like_model
+    @author = HashBackedAuthor.new
+
+    form_with(model: @post) do |f|
+      concat f.fields(:author, model: @author) { |af|
+        concat af.text_field(:name)
+      }
+    end
+
+    expected = whole_form("/posts/123", method: "patch") do
+      '<input name="post[author_attributes][name]" type="text" value="hash backed author" id="post_author_attributes_name" />'
+    end
+
+    assert_dom_equal expected, output_buffer
+  end
+
+  def test_fields
+    output_buffer = fields(:post, model: @post) do |f|
+      concat f.text_field(:title)
+      concat f.text_area(:body)
+      concat f.check_box(:secret)
+    end
+
+    expected =
+      "<input name='post[title]' type='text' value='Hello World' id='post_title' />" \
+      "<textarea name='post[body]' id='post_body'>\nBack to the hill and over it again!</textarea>" \
+      "<input name='post[secret]' type='hidden' value='0' />" \
+      "<input name='post[secret]' checked='checked' type='checkbox' value='1' id='post_secret' />"
+
+    assert_dom_equal expected, output_buffer
+  end
+
+  def test_fields_with_index
+    output_buffer = fields("post[]", model: @post) do |f|
+      concat f.text_field(:title)
+      concat f.text_area(:body)
+      concat f.check_box(:secret)
+    end
+
+    expected =
+      "<input name='post[123][title]' type='text' value='Hello World' id='post_123_title' />" \
+      "<textarea name='post[123][body]' id='post_123_body'>\nBack to the hill and over it again!</textarea>" \
+      "<input name='post[123][secret]' type='hidden' value='0' />" \
+      "<input name='post[123][secret]' checked='checked' type='checkbox' value='1' id='post_123_secret' />"
+
+    assert_dom_equal expected, output_buffer
+  end
+
+  def test_fields_with_nil_index_option_override
+    output_buffer = fields("post[]", model: @post, index: nil) do |f|
+      concat f.text_field(:title)
+      concat f.text_area(:body)
+      concat f.check_box(:secret)
+    end
+
+    expected =
+      "<input name='post[][title]' type='text' value='Hello World' id='post__title' />" \
+      "<textarea name='post[][body]' id='post__body'>\nBack to the hill and over it again!</textarea>" \
+      "<input name='post[][secret]' type='hidden' value='0' />" \
+      "<input name='post[][secret]' checked='checked' type='checkbox' value='1' id='post__secret' />"
+
+    assert_dom_equal expected, output_buffer
+  end
+
+  def test_fields_with_index_option_override
+    output_buffer = fields("post[]", model: @post, index: "abc") do |f|
+      concat f.text_field(:title)
+      concat f.text_area(:body)
+      concat f.check_box(:secret)
+    end
+
+    expected =
+      "<input name='post[abc][title]' type='text' value='Hello World' id='post_abc_title' />" \
+      "<textarea name='post[abc][body]' id='post_abc_body'>\nBack to the hill and over it again!</textarea>" \
+      "<input name='post[abc][secret]' type='hidden' value='0' />" \
+      "<input name='post[abc][secret]' checked='checked' type='checkbox' value='1' id='post_abc_secret' />"
+
+    assert_dom_equal expected, output_buffer
+  end
+
+  def test_fields_without_object
+    output_buffer = fields(:post) do |f|
+      concat f.text_field(:title)
+      concat f.text_area(:body)
+      concat f.check_box(:secret)
+    end
+
+    expected =
+      "<input name='post[title]' type='text' value='Hello World' id='post_title' />" \
+      "<textarea name='post[body]' id='post_body' >\nBack to the hill and over it again!</textarea>" \
+      "<input name='post[secret]' type='hidden' value='0' />" \
+      "<input name='post[secret]' checked='checked' type='checkbox' value='1' id='post_secret' />"
+
+    assert_dom_equal expected, output_buffer
+  end
+
+  def test_fields_with_only_object
+    output_buffer = fields(model: @post) do |f|
+      concat f.text_field(:title)
+      concat f.text_area(:body)
+      concat f.check_box(:secret)
+    end
+
+    expected =
+      "<input name='post[title]' type='text' value='Hello World' id='post_title' />" \
+      "<textarea name='post[body]' id='post_body' >\nBack to the hill and over it again!</textarea>" \
+      "<input name='post[secret]' type='hidden' value='0' />" \
+      "<input name='post[secret]' checked='checked' type='checkbox' value='1' id='post_secret' />"
+
+    assert_dom_equal expected, output_buffer
+  end
+
+  def test_fields_object_with_bracketed_name
+    output_buffer = fields("author[post]", model: @post) do |f|
+      concat f.label(:title)
+      concat f.text_field(:title)
+    end
+
+    assert_dom_equal "<label for=\"author_post_title\">Title</label>" \
+    "<input name='author[post][title]' type='text' value='Hello World' id='author_post_title' id='author_post_1_title' />",
+      output_buffer
+  end
+
+  def test_fields_object_with_bracketed_name_and_index
+    output_buffer = fields("author[post]", model: @post, index: 1) do |f|
+      concat f.label(:title)
+      concat f.text_field(:title)
+    end
+
+    assert_dom_equal "<label for=\"author_post_1_title\">Title</label>" \
+      "<input name='author[post][1][title]' type='text' value='Hello World' id='author_post_1_title' />",
+      output_buffer
+  end
+
+  def test_form_builder_does_not_have_form_with_method
+    assert_not_includes ActionView::Helpers::FormBuilder.instance_methods, :form_with
+  end
+
+  def test_form_with_and_fields
+    form_with(model: @post, scope: :post, id: "create-post") do |post_form|
+      concat post_form.text_field(:title)
+      concat post_form.text_area(:body)
+
+      concat fields(:parent_post, model: @post) { |parent_fields|
+        concat parent_fields.check_box(:secret)
+      }
+    end
+
+    expected = whole_form("/posts/123", "create-post", method: "patch") do
+      "<input name='post[title]' type='text' value='Hello World' id='post_title' />" \
+      "<textarea name='post[body]' id='post_body' >\nBack to the hill and over it again!</textarea>" \
+      "<input name='parent_post[secret]' type='hidden' value='0' />" \
+      "<input name='parent_post[secret]' checked='checked' type='checkbox' value='1' id='parent_post_secret' />"
+    end
+
+    assert_dom_equal expected, output_buffer
+  end
+
+  def test_form_with_and_fields_with_object
+    form_with(model: @post, scope: :post, id: "create-post") do |post_form|
+      concat post_form.text_field(:title)
+      concat post_form.text_area(:body)
+
+      concat post_form.fields(model: @comment) { |comment_fields|
+        concat comment_fields.text_field(:name)
+      }
+    end
+
+    expected = whole_form("/posts/123", "create-post", method: "patch") do
+      "<input name='post[title]' type='text' value='Hello World' id='post_title' />" \
+      "<textarea name='post[body]' id='post_body'>\nBack to the hill and over it again!</textarea>" \
+      "<input name='post[comment][name]' type='text' value='new comment' id='post_comment_name' />"
+    end
+
+    assert_dom_equal expected, output_buffer
+  end
+
+  def test_form_with_and_fields_with_non_nested_association_and_without_object
+    form_with(model: @post) do |f|
+      concat f.fields(:category) { |c|
+        concat c.text_field(:name)
+      }
+    end
+
+    expected = whole_form("/posts/123", method: "patch") do
+      "<input name='post[category][name]' type='text' id='post_category_name' />"
+    end
+
+    assert_dom_equal expected, output_buffer
+  end
+
+  class LabelledFormBuilder < ActionView::Helpers::FormBuilder
+    (field_helpers - %w(hidden_field)).each do |selector|
+      class_eval <<-RUBY_EVAL, __FILE__, __LINE__ + 1
+        def #{selector}(field, *args, &proc)
+          ("<label for='\#{field}'>\#{field.to_s.humanize}:</label> " + super + "<br/>").html_safe
+        end
+      RUBY_EVAL
+    end
+  end
+
+  def test_form_with_with_labelled_builder
+    form_with(model: @post, builder: LabelledFormBuilder) do |f|
+      concat f.text_field(:title)
+      concat f.text_area(:body)
+      concat f.check_box(:secret)
+    end
+
+    expected = whole_form("/posts/123", method: "patch") do
+      "<label for='title'>Title:</label> <input name='post[title]' type='text' value='Hello World' id='post_title'/><br/>" \
+      "<label for='body'>Body:</label> <textarea name='post[body]' id='post_body'>\nBack to the hill and over it again!</textarea><br/>" \
+      "<label for='secret'>Secret:</label> <input name='post[secret]' type='hidden' value='0' /><input name='post[secret]' checked='checked' type='checkbox' value='1' id='post_secret' /><br/>"
+    end
+
+    assert_dom_equal expected, output_buffer
+  end
+
+  def test_default_form_builder
+    old_default_form_builder, ActionView::Base.default_form_builder =
+      ActionView::Base.default_form_builder, LabelledFormBuilder
+
+    form_with(model: @post) do |f|
+      concat f.text_field(:title)
+      concat f.text_area(:body)
+      concat f.check_box(:secret)
+    end
+
+    expected = whole_form("/posts/123", method: "patch") do
+      "<label for='title'>Title:</label> <input name='post[title]' type='text' value='Hello World' id='post_title' /><br/>" \
+      "<label for='body'>Body:</label> <textarea name='post[body]' id='post_body'>\nBack to the hill and over it again!</textarea><br/>" \
+      "<label for='secret'>Secret:</label> <input name='post[secret]' type='hidden' value='0' /><input name='post[secret]' checked='checked' type='checkbox' value='1' id='post_secret' /><br/>"
+    end
+
+    assert_dom_equal expected, output_buffer
+  ensure
+    ActionView::Base.default_form_builder = old_default_form_builder
+  end
+
+  def test_lazy_loading_default_form_builder
+    old_default_form_builder, ActionView::Base.default_form_builder =
+      ActionView::Base.default_form_builder, "FormWithActsLikeFormForTest::LabelledFormBuilder"
+
+    form_with(model: @post) do |f|
+      concat f.text_field(:title)
+    end
+
+    expected = whole_form("/posts/123", method: "patch") do
+      "<label for='title'>Title:</label> <input name='post[title]' type='text' value='Hello World' id='post_title' /><br/>"
+    end
+
+    assert_dom_equal expected, output_buffer
+  ensure
+    ActionView::Base.default_form_builder = old_default_form_builder
+  end
+
+  def test_form_builder_override
+    self.default_form_builder = LabelledFormBuilder
+
+    output_buffer = fields(:post, model: @post) do |f|
+      concat f.text_field(:title)
+    end
+
+    expected = "<label for='title'>Title:</label> <input name='post[title]' type='text' value='Hello World' id='post_title' /><br/>"
+
+    assert_dom_equal expected, output_buffer
+  end
+
+  def test_lazy_loading_form_builder_override
+    self.default_form_builder = "FormWithActsLikeFormForTest::LabelledFormBuilder"
+
+    output_buffer = fields(:post, model: @post) do |f|
+      concat f.text_field(:title)
+    end
+
+    expected = "<label for='title'>Title:</label> <input name='post[title]' type='text' value='Hello World' id='post_title' /><br/>"
+
+    assert_dom_equal expected, output_buffer
+  end
+
+  def test_fields_with_labelled_builder
+    output_buffer = fields(:post, model: @post, builder: LabelledFormBuilder) do |f|
+      concat f.text_field(:title)
+      concat f.text_area(:body)
+      concat f.check_box(:secret)
+    end
+
+    expected =
+      "<label for='title'>Title:</label> <input name='post[title]' type='text' value='Hello World' id='post_title'/><br/>" \
+      "<label for='body'>Body:</label> <textarea name='post[body]' id='post_body'>\nBack to the hill and over it again!</textarea><br/>" \
+      "<label for='secret'>Secret:</label> <input name='post[secret]' type='hidden' value='0' /><input name='post[secret]' checked='checked' type='checkbox' value='1' id='post_secret' /><br/>"
+
+    assert_dom_equal expected, output_buffer
+  end
+
+  def test_form_with_with_labelled_builder_with_nested_fields_without_options_hash
+    klass = nil
+
+    form_with(model: @post, builder: LabelledFormBuilder) do |f|
+      f.fields(:comments, model: Comment.new) do |nested_fields|
+        klass = nested_fields.class
+        ""
+      end
+    end
+
+    assert_equal LabelledFormBuilder, klass
+  end
+
+  def test_form_with_with_labelled_builder_with_nested_fields_with_options_hash
+    klass = nil
+
+    form_with(model: @post, builder: LabelledFormBuilder) do |f|
+      f.fields(:comments, model: Comment.new, index: "foo") do |nested_fields|
+        klass = nested_fields.class
+        ""
+      end
+    end
+
+    assert_equal LabelledFormBuilder, klass
+  end
+
+  def test_form_with_with_labelled_builder_path
+    path = nil
+
+    form_with(model: @post, builder: LabelledFormBuilder) do |f|
+      path = f.to_partial_path
+      ""
+    end
+
+    assert_equal "labelled_form", path
+  end
+
+  class LabelledFormBuilderSubclass < LabelledFormBuilder; end
+
+  def test_form_with_with_labelled_builder_with_nested_fields_with_custom_builder
+    klass = nil
+
+    form_with(model: @post, builder: LabelledFormBuilder) do |f|
+      f.fields(:comments, model: Comment.new, builder: LabelledFormBuilderSubclass) do |nested_fields|
+        klass = nested_fields.class
+        ""
+      end
+    end
+
+    assert_equal LabelledFormBuilderSubclass, klass
+  end
+
+  def test_form_with_with_html_options_adds_options_to_form_tag
+    form_with(model: @post, html: { id: "some_form", class: "some_class", multipart: true }) do |f| end
+    expected = whole_form("/posts/123", "some_form", "some_class", method: "patch", multipart: "multipart/form-data")
+
+    assert_dom_equal expected, output_buffer
+  end
+
+  def test_form_with_with_string_url_option
+    form_with(model: @post, url: "http://www.otherdomain.com") do |f| end
+
+    assert_dom_equal whole_form("http://www.otherdomain.com", method: "patch"), output_buffer
+  end
+
+  def test_form_with_with_hash_url_option
+    form_with(model: @post, url: { controller: "controller", action: "action" }) do |f| end
+
+    assert_equal "controller", @url_for_options[:controller]
+    assert_equal "action", @url_for_options[:action]
+  end
+
+  def test_form_with_with_record_url_option
+    form_with(model: @post, url: @post) do |f| end
+
+    expected = whole_form("/posts/123", method: "patch")
+    assert_dom_equal expected, output_buffer
+  end
+
+  def test_form_with_with_existing_object
+    form_with(model: @post) do |f| end
+
+    expected = whole_form("/posts/123", method: "patch")
+    assert_dom_equal expected, output_buffer
+  end
+
+  def test_form_with_with_new_object
+    post = Post.new
+    post.persisted = false
+    def post.to_key; nil; end
+
+    form_with(model: post) {}
+
+    expected = whole_form("/posts")
+    assert_dom_equal expected, output_buffer
+  end
+
+  def test_form_with_with_existing_object_in_list
+    @comment.save
+    form_with(model: [@post, @comment]) {}
+
+    expected = whole_form(post_comment_path(@post, @comment), method: "patch")
+    assert_dom_equal expected, output_buffer
+  end
+
+  def test_form_with_with_new_object_in_list
+    form_with(model: [@post, @comment]) {}
+
+    expected = whole_form(post_comments_path(@post))
+    assert_dom_equal expected, output_buffer
+  end
+
+  def test_form_with_with_existing_object_and_namespace_in_list
+    @comment.save
+    form_with(model: [:admin, @post, @comment]) {}
+
+    expected = whole_form(admin_post_comment_path(@post, @comment), method: "patch")
+    assert_dom_equal expected, output_buffer
+  end
+
+  def test_form_with_with_new_object_and_namespace_in_list
+    form_with(model: [:admin, @post, @comment]) {}
+
+    expected = whole_form(admin_post_comments_path(@post))
+    assert_dom_equal expected, output_buffer
+  end
+
+  def test_form_with_with_existing_object_and_custom_url
+    form_with(model: @post, url: "/super_posts") do |f| end
+
+    expected = whole_form("/super_posts", method: "patch")
+    assert_dom_equal expected, output_buffer
+  end
+
+  def test_form_with_with_default_method_as_patch
+    form_with(model: @post) {}
+    expected = whole_form("/posts/123", method: "patch")
+    assert_dom_equal expected, output_buffer
+  end
+
+  def test_form_with_with_data_attributes
+    form_with(model: @post, data: { behavior: "stuff" }) {}
+    assert_match %r|data-behavior="stuff"|, output_buffer
+    assert_match %r|data-remote="true"|, output_buffer
+  end
+
+  def test_fields_returns_block_result
+    output = fields(model: Post.new) { |f| "fields" }
+    assert_equal "fields", output
+  end
+
+  def test_form_with_only_instantiates_builder_once
+    initialization_count = 0
+    builder_class = Class.new(ActionView::Helpers::FormBuilder) do
+      define_method :initialize do |*args|
+        super(*args)
+        initialization_count += 1
+      end
+    end
+
+    form_with(model: @post, builder: builder_class) {}
+    assert_equal 1, initialization_count, "form builder instantiated more than once"
+  end
+
+  private
+    def hidden_fields(options = {})
+      method = options[:method]
+
+      if options.fetch(:skip_enforcing_utf8, false)
+        txt = "".dup
+      else
+        txt = %{<input name="utf8" type="hidden" value="&#x2713;" />}.dup
+      end
+
+      if method && !%w(get post).include?(method.to_s)
+        txt << %{<input name="_method" type="hidden" value="#{method}" />}
+      end
+
+      txt
+    end
+
+    def form_text(action = "/", id = nil, html_class = nil, local = nil, multipart = nil, method = nil)
+      txt =  %{<form accept-charset="UTF-8" action="#{action}"}.dup
+      txt << %{ enctype="multipart/form-data"} if multipart
+      txt << %{ data-remote="true"} unless local
+      txt << %{ class="#{html_class}"} if html_class
+      txt << %{ id="#{id}"} if id
+      method = method.to_s == "get" ? "get" : "post"
+      txt << %{ method="#{method}">}
+    end
+
+    def whole_form(action = "/", id = nil, html_class = nil, local: false, **options)
+      contents = block_given? ? yield : ""
+
+      method, multipart = options.values_at(:method, :multipart)
+
+      form_text(action, id, html_class, local, multipart, method) + hidden_fields(options.slice :method, :skip_enforcing_utf8) + contents + "</form>"
+    end
+
+    def protect_against_forgery?
+      false
+    end
+
+    def with_locale(testing_locale = :label)
+      old_locale, I18n.locale = I18n.locale, testing_locale
+      yield
+    ensure
+      I18n.locale = old_locale
+    end
+end
diff --git a/actionview/test/template/form_helper_test.rb b/actionview/test/template/form_helper_test.rb
index 310d0ce514..6a317e1a12 100644
--- a/actionview/test/template/form_helper_test.rb
+++ b/actionview/test/template/form_helper_test.rb
@@ -1,11 +1,23 @@
-require 'abstract_unit'
-require 'controller/fake_models'
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "controller/fake_models"
 
 class FormHelperTest < ActionView::TestCase
   include RenderERBUtils
 
   tests ActionView::Helpers::FormHelper
 
+  class WithActiveStorageRoutesControllers < ActionController::Base
+    test_routes do
+      post "/rails/active_storage/direct_uploads" => "active_storage/direct_uploads#create", as: :rails_direct_uploads
+    end
+
+    def url_options
+      { host: "testtwo.host" }
+    end
+  end
+
   def form_for(*)
     @output_buffer = super
   end
@@ -16,13 +28,13 @@ class FormHelperTest < ActionView::TestCase
 
   setup do
     # Create "label" locale for testing I18n label helpers
-    I18n.backend.store_translations 'label', {
+    I18n.backend.store_translations "label",
       activemodel: {
         attributes: {
           post: {
             cost: "Total cost"
           },
-          :"post/language" => {
+          "post/language": {
             spanish: "Espanol"
           }
         }
@@ -42,33 +54,31 @@ class FormHelperTest < ActionView::TestCase
             value: "Tag"
           },
           post_delegate: {
-            title: 'Delegate model_name title'
+            title: "Delegate model_name title"
           }
         }
       }
-    }
 
     # Create "submit" locale for testing I18n submit helpers
-    I18n.backend.store_translations 'submit', {
+    I18n.backend.store_translations "submit",
       helpers: {
         submit: {
-          create: 'Create %{model}',
-          update: 'Confirm %{model} changes',
-          submit: 'Save changes',
+          create: "Create %{model}",
+          update: "Confirm %{model} changes",
+          submit: "Save changes",
           another_post: {
-            update: 'Update your %{model}'
+            update: "Update your %{model}"
           }
         }
       }
-    }
 
-    I18n.backend.store_translations 'placeholder', {
+    I18n.backend.store_translations "placeholder",
       activemodel: {
         attributes: {
           post: {
             cost: "Total cost"
           },
-          :"post/cost" => {
+          "post/cost": {
             uk: "Pounds"
           }
         }
@@ -85,18 +95,17 @@ class FormHelperTest < ActionView::TestCase
             }
           },
           post_delegate: {
-            title: 'Delegate model_name title'
+            title: "Delegate model_name title"
           },
           tag: {
             value: "Tag"
           }
         }
       }
-    }
 
     @post = Post.new
     @comment = Comment.new
-    def @post.errors()
+    def @post.errors
       Class.new {
         def [](field); field == "author_name" ? ["can't be empty"] : [] end
         def empty?() false end
@@ -108,7 +117,7 @@ class FormHelperTest < ActionView::TestCase
     def @post.id; 0; end
     def @post.id_before_type_cast; "omg"; end
     def @post.id_came_from_user?; true; end
-    def @post.to_param; '123'; end
+    def @post.to_param; "123"; end
 
     @post.persisted   = true
     @post.title       = "Hello World"
@@ -125,7 +134,7 @@ class FormHelperTest < ActionView::TestCase
 
     @post_delegator = PostDelegator.new
 
-    @post_delegator.title = 'Hello World'
+    @post_delegator.title = "Hello World"
 
     @car = Car.new("#000FFF")
   end
@@ -178,7 +187,7 @@ class FormHelperTest < ActionView::TestCase
     )
     assert_dom_equal(
       '<label class="title_label" for="post_title">Title</label>',
-      label("post", "title", nil, class: 'title_label')
+      label("post", "title", nil, class: "title_label")
     )
     assert_dom_equal('<label for="post_secret">Secret?</label>', label("post", "secret?"))
   end
@@ -229,7 +238,7 @@ class FormHelperTest < ActionView::TestCase
 
   def test_label_with_locales_and_nested_attributes
     with_locale :label do
-      form_for(@post, html: { id: 'create-post' }) do |f|
+      form_for(@post, html: { id: "create-post" }) do |f|
         f.fields_for(:comments) do |cf|
           concat cf.label(:body)
         end
@@ -245,7 +254,7 @@ class FormHelperTest < ActionView::TestCase
 
   def test_label_with_locales_fallback_and_nested_attributes
     with_locale :label do
-      form_for(@post, html: { id: 'create-post' }) do |f|
+      form_for(@post, html: { id: "create-post" }) do |f|
         f.fields_for(:tags) do |cf|
           concat cf.label(:value)
         end
@@ -260,11 +269,11 @@ class FormHelperTest < ActionView::TestCase
   end
 
   def test_label_with_non_active_record_object
-    form_for(OpenStruct.new(name:'ok'), as: 'person', url: 'an_url', html: { id: 'create-person' }) do |f|
+    form_for(OpenStruct.new(name: "ok"), as: "person", url: "/an", html: { id: "create-person" }) do |f|
       f.label(:name)
     end
 
-    expected = whole_form("an_url", "create-person", "new_person", method: "post") do
+    expected = whole_form("/an", "create-person", "new_person", method: "post") do
       '<label for="person_name">Name</label>'
     end
 
@@ -280,7 +289,7 @@ class FormHelperTest < ActionView::TestCase
   end
 
   def test_label_does_not_generate_for_attribute_when_given_nil
-    assert_dom_equal('<label>Title</label>', label(:post, :title, for: nil))
+    assert_dom_equal("<label>Title</label>", label(:post, :title, for: nil))
   end
 
   def test_label_with_id_attribute_as_symbol
@@ -429,7 +438,7 @@ class FormHelperTest < ActionView::TestCase
 
   def test_text_field_placeholder_with_locales_and_nested_attributes
     with_locale :placeholder do
-      form_for(@post, html: { id: 'create-post' }) do |f|
+      form_for(@post, html: { id: "create-post" }) do |f|
         f.fields_for(:comments) do |cf|
           concat cf.text_field(:body, placeholder: true)
         end
@@ -445,7 +454,7 @@ class FormHelperTest < ActionView::TestCase
 
   def test_text_field_placeholder_with_locales_fallback_and_nested_attributes
     with_locale :placeholder do
-      form_for(@post, html: { id: 'create-post' }) do |f|
+      form_for(@post, html: { id: "create-post" }) do |f|
         f.fields_for(:tags) do |cf|
           concat cf.text_field(:value, placeholder: true)
         end
@@ -523,39 +532,45 @@ class FormHelperTest < ActionView::TestCase
   end
 
   def test_text_field_doesnt_change_param_values
-    object_name = 'post[]'
+    object_name = "post[]"
     expected = '<input id="post_123_title" name="post[123][title]" type="text" value="Hello World" />'
     assert_dom_equal expected, text_field(object_name, "title")
   end
 
-  def test_file_field_does_generate_a_hidden_field
-    expected = '<input name="user[avatar]" type="hidden" value="" /><input id="user_avatar" name="user[avatar]" type="file" />'
+  def test_file_field_has_no_size
+    expected = '<input id="user_avatar" name="user[avatar]" type="file" />'
     assert_dom_equal expected, file_field("user", "avatar")
   end
 
-  def test_file_field_does_not_generate_a_hidden_field_if_included_hidden_option_is_false
-    expected = '<input id="user_avatar" name="user[avatar]" type="file" />'
-    assert_dom_equal expected, file_field("user", "avatar", include_hidden: false)
+  def test_file_field_with_multiple_behavior
+    expected = '<input id="import_file" multiple="multiple" name="import[file][]" type="file" />'
+    assert_dom_equal expected, file_field("import", "file", multiple: true)
   end
 
-  def test_file_field_does_not_generate_a_hidden_field_if_included_hidden_option_is_false_with_key_as_string
-    expected = '<input id="user_avatar" name="user[avatar]" type="file" />'
-    assert_dom_equal expected, file_field("user", "avatar", "include_hidden" => false)
+  def test_file_field_with_multiple_behavior_and_explicit_name
+    expected = '<input id="import_file" multiple="multiple" name="custom" type="file" />'
+    assert_dom_equal expected, file_field("import", "file", multiple: true, name: "custom")
   end
 
-  def test_file_field_has_no_size
-    expected = '<input name="user[avatar]" type="hidden" value="" /><input id="user_avatar" name="user[avatar]" type="file" />'
-    assert_dom_equal expected, file_field("user", "avatar")
+  def test_file_field_with_direct_upload_when_rails_direct_uploads_url_is_not_defined
+    expected = '<input type="file" name="import[file]" id="import_file" />'
+    assert_dom_equal expected, file_field("import", "file", direct_upload: true)
   end
 
-  def test_file_field_with_multiple_behavior
-    expected = '<input name="import[file][]" type="hidden" value="" /><input id="import_file" multiple="multiple" name="import[file][]" type="file" />'
-    assert_dom_equal expected, file_field("import", "file", :multiple => true)
+  def test_file_field_with_direct_upload_when_rails_direct_uploads_url_is_defined
+    @controller = WithActiveStorageRoutesControllers.new
+
+    expected = '<input data-direct-upload-url="http://testtwo.host/rails/active_storage/direct_uploads" type="file" name="import[file]" id="import_file" />'
+    assert_dom_equal expected, file_field("import", "file", direct_upload: true)
   end
 
-  def test_file_field_with_multiple_behavior_and_explicit_name
-    expected = '<input name="custom" type="hidden" value="" /><input id="import_file" multiple="multiple" name="custom" type="file" />'
-    assert_dom_equal expected, file_field("import", "file", :multiple => true, :name => "custom")
+  def test_file_field_with_direct_upload_dont_mutate_arguments
+    original_options = { class: "pix", direct_upload: true }
+
+    expected = '<input class="pix" type="file" name="import[file]" id="import_file" />'
+    assert_dom_equal expected, file_field("import", "file", original_options)
+
+    assert_equal({ class: "pix", direct_upload: true }, original_options)
   end
 
   def test_hidden_field
@@ -618,7 +633,7 @@ class FormHelperTest < ActionView::TestCase
   def test_check_box_checked_if_option_checked_is_present
     assert_dom_equal(
       '<input name="post[secret]" type="hidden" value="0" /><input checked="checked" id="post_secret" name="post[secret]" type="checkbox" value="1" />',
-      check_box("post", "secret", "checked"=>"checked")
+      check_box("post", "secret", "checked" => "checked")
     )
   end
 
@@ -636,19 +651,19 @@ class FormHelperTest < ActionView::TestCase
   end
 
   def test_check_box_checked_if_object_value_includes_checked_value
-    @post.secret = ['0']
+    @post.secret = ["0"]
     assert_dom_equal(
       '<input name="post[secret]" type="hidden" value="0" /><input id="post_secret" name="post[secret]" type="checkbox" value="1" />',
       check_box("post", "secret")
     )
 
-    @post.secret = ['1']
+    @post.secret = ["1"]
     assert_dom_equal(
       '<input name="post[secret]" type="hidden" value="0" /><input checked="checked" id="post_secret" name="post[secret]" type="checkbox" value="1" />',
       check_box("post", "secret")
     )
 
-    @post.secret = Set.new(['1'])
+    @post.secret = Set.new(["1"])
     assert_dom_equal(
       '<input name="post[secret]" type="hidden" value="0" /><input checked="checked" id="post_secret" name="post[secret]" type="checkbox" value="1" />',
       check_box("post", "secret")
@@ -732,19 +747,19 @@ class FormHelperTest < ActionView::TestCase
   end
 
   def test_check_box_with_explicit_checked_and_unchecked_values_when_object_value_is_big_decimal
-    @post.secret = BigDecimal.new(0)
+    @post.secret = BigDecimal(0)
     assert_dom_equal(
       '<input name="post[secret]" type="hidden" value="1" /><input checked="checked" id="post_secret" name="post[secret]" type="checkbox" value="0" />',
       check_box("post", "secret", {}, 0, 1)
     )
 
-    @post.secret = BigDecimal.new(1)
+    @post.secret = BigDecimal(1)
     assert_dom_equal(
       '<input name="post[secret]" type="hidden" value="1" /><input id="post_secret" name="post[secret]" type="checkbox" value="0" />',
       check_box("post", "secret", {}, 0, 1)
     )
 
-    @post.secret = BigDecimal.new(2.2, 1)
+    @post.secret = BigDecimal(2.2, 1)
     assert_dom_equal(
       '<input name="post[secret]" type="hidden" value="1" /><input id="post_secret" name="post[secret]" type="checkbox" value="0" />',
       check_box("post", "secret", {}, 0, 1)
@@ -764,7 +779,7 @@ class FormHelperTest < ActionView::TestCase
   end
 
   def test_check_box_with_multiple_behavior
-    @post.comment_ids = [2,3]
+    @post.comment_ids = [2, 3]
     assert_dom_equal(
       '<input name="post[comment_ids][]" type="hidden" value="0" /><input id="post_comment_ids_1" name="post[comment_ids][]" type="checkbox" value="1" />',
       check_box("post", "comment_ids", { multiple: true }, 1)
@@ -776,7 +791,7 @@ class FormHelperTest < ActionView::TestCase
   end
 
   def test_check_box_with_multiple_behavior_and_index
-    @post.comment_ids = [2,3]
+    @post.comment_ids = [2, 3]
     assert_dom_equal(
       '<input name="post[foo][comment_ids][]" type="hidden" value="0" /><input id="post_foo_comment_ids_1" name="post[foo][comment_ids][]" type="checkbox" value="1" />',
       check_box("post", "comment_ids", { multiple: true, index: "foo" }, 1)
@@ -785,13 +800,12 @@ class FormHelperTest < ActionView::TestCase
       '<input name="post[bar][comment_ids][]" type="hidden" value="0" /><input checked="checked" id="post_bar_comment_ids_3" name="post[bar][comment_ids][]" type="checkbox" value="3" />',
       check_box("post", "comment_ids", { multiple: true, index: "bar" }, 3)
     )
-
   end
 
   def test_checkbox_disabled_disables_hidden_field
     assert_dom_equal(
       '<input name="post[secret]" type="hidden" value="0" disabled="disabled"/><input checked="checked" disabled="disabled" id="post_secret" name="post[secret]" type="checkbox" value="1" />',
-      check_box("post", "secret", { disabled: true })
+      check_box("post", "secret", disabled: true)
     )
   end
 
@@ -826,9 +840,9 @@ class FormHelperTest < ActionView::TestCase
   end
 
   def test_radio_button_respects_passed_in_id
-     assert_dom_equal('<input checked="checked" id="foo" name="post[secret]" type="radio" value="1" />',
-       radio_button("post", "secret", "1", id: "foo")
-    )
+    assert_dom_equal('<input checked="checked" id="foo" name="post[secret]" type="radio" value="1" />',
+      radio_button("post", "secret", "1", id: "foo")
+   )
   end
 
   def test_radio_button_with_booleans
@@ -897,7 +911,7 @@ class FormHelperTest < ActionView::TestCase
 
   def test_text_area_placeholder_with_locales_and_nested_attributes
     with_locale :placeholder do
-      form_for(@post, html: { id: 'create-post' }) do |f|
+      form_for(@post, html: { id: "create-post" }) do |f|
         f.fields_for(:comments) do |cf|
           concat cf.text_area(:body, placeholder: true)
         end
@@ -913,7 +927,7 @@ class FormHelperTest < ActionView::TestCase
 
   def test_text_area_placeholder_with_locales_fallback_and_nested_attributes
     with_locale :placeholder do
-      form_for(@post, html: { id: 'create-post' }) do |f|
+      form_for(@post, html: { id: "create-post" }) do |f|
         f.fields_for(:tags) do |cf|
           concat cf.text_area(:value, placeholder: true)
         end
@@ -1051,14 +1065,14 @@ class FormHelperTest < ActionView::TestCase
 
   def test_date_field_with_value_attr
     expected = %{<input id="post_written_on" name="post[written_on]" type="date" value="2013-06-29" />}
-    value = Date.new(2013,6,29)
+    value = Date.new(2013, 6, 29)
     assert_dom_equal(expected, date_field("post", "written_on", value: value))
   end
 
   def test_date_field_with_timewithzone_value
-    previous_time_zone, Time.zone = Time.zone, 'UTC'
+    previous_time_zone, Time.zone = Time.zone, "UTC"
     expected = %{<input id="post_written_on" name="post[written_on]" type="date" value="2004-06-15" />}
-    @post.written_on = Time.zone.parse('2004-06-15 15:30:45')
+    @post.written_on = Time.zone.parse("2004-06-15 15:30:45")
     assert_dom_equal(expected, date_field("post", "written_on"))
   ensure
     Time.zone = previous_time_zone
@@ -1107,9 +1121,9 @@ class FormHelperTest < ActionView::TestCase
   end
 
   def test_time_field_with_timewithzone_value
-    previous_time_zone, Time.zone = Time.zone, 'UTC'
+    previous_time_zone, Time.zone = Time.zone, "UTC"
     expected = %{<input id="post_written_on" name="post[written_on]" type="time" value="01:02:03.000" />}
-    @post.written_on = Time.zone.parse('2004-06-15 01:02:03')
+    @post.written_on = Time.zone.parse("2004-06-15 01:02:03")
     assert_dom_equal(expected, time_field("post", "written_on"))
   ensure
     Time.zone = previous_time_zone
@@ -1138,76 +1152,60 @@ class FormHelperTest < ActionView::TestCase
   end
 
   def test_datetime_field
-    expected = %{<input id="post_written_on" name="post[written_on]" type="datetime" value="2004-06-15T00:00:00.000+0000" />}
-    assert_deprecated do
-      assert_dom_equal(expected, datetime_field("post", "written_on"))
-    end
+    expected = %{<input id="post_written_on" name="post[written_on]" type="datetime-local" value="2004-06-15T00:00:00" />}
+    assert_dom_equal(expected, datetime_field("post", "written_on"))
   end
 
   def test_datetime_field_with_datetime_value
-    expected = %{<input id="post_written_on" name="post[written_on]" type="datetime" value="2004-06-15T01:02:03.000+0000" />}
+    expected = %{<input id="post_written_on" name="post[written_on]" type="datetime-local" value="2004-06-15T01:02:03" />}
     @post.written_on = DateTime.new(2004, 6, 15, 1, 2, 3)
-    assert_deprecated do
-      assert_dom_equal(expected, datetime_field("post", "written_on"))
-    end
+    assert_dom_equal(expected, datetime_field("post", "written_on"))
   end
 
   def test_datetime_field_with_extra_attrs
-    expected = %{<input id="post_written_on" step="60" max="2010-08-15T10:25:00.000+0000" min="2000-06-15T20:45:30.000+0000" name="post[written_on]" type="datetime" value="2004-06-15T01:02:03.000+0000" />}
+    expected = %{<input id="post_written_on" step="60" max="2010-08-15T10:25:00" min="2000-06-15T20:45:30" name="post[written_on]" type="datetime-local" value="2004-06-15T01:02:03" />}
     @post.written_on = DateTime.new(2004, 6, 15, 1, 2, 3)
     min_value = DateTime.new(2000, 6, 15, 20, 45, 30)
     max_value = DateTime.new(2010, 8, 15, 10, 25, 00)
     step = 60
-    assert_deprecated do
-      assert_dom_equal(expected, datetime_field("post", "written_on", min: min_value, max: max_value, step: step))
-    end
+    assert_dom_equal(expected, datetime_field("post", "written_on", min: min_value, max: max_value, step: step))
   end
 
   def test_datetime_field_with_value_attr
-    expected = %{<input id="post_written_on" name="post[written_on]" type="datetime" value="2013-06-29T13:37:00+00:00" />}
-    value = DateTime.new(2013,6,29,13,37)
-    assert_deprecated do
-      assert_dom_equal(expected, datetime_field("post", "written_on", value: value))
-    end
+    expected = %{<input id="post_written_on" name="post[written_on]" type="datetime-local" value="2013-06-29T13:37:00+00:00" />}
+    value = DateTime.new(2013, 6, 29, 13, 37)
+    assert_dom_equal(expected, datetime_field("post", "written_on", value: value))
   end
 
   def test_datetime_field_with_timewithzone_value
-    previous_time_zone, Time.zone = Time.zone, 'UTC'
-    expected = %{<input id="post_written_on" name="post[written_on]" type="datetime" value="2004-06-15T15:30:45.000+0000" />}
-    @post.written_on = Time.zone.parse('2004-06-15 15:30:45')
-    assert_deprecated do
-      assert_dom_equal(expected, datetime_field("post", "written_on"))
-    end
+    previous_time_zone, Time.zone = Time.zone, "UTC"
+    expected = %{<input id="post_written_on" name="post[written_on]" type="datetime-local" value="2004-06-15T15:30:45" />}
+    @post.written_on = Time.zone.parse("2004-06-15 15:30:45")
+    assert_dom_equal(expected, datetime_field("post", "written_on"))
   ensure
     Time.zone = previous_time_zone
   end
 
   def test_datetime_field_with_nil_value
-    expected = %{<input id="post_written_on" name="post[written_on]" type="datetime" />}
+    expected = %{<input id="post_written_on" name="post[written_on]" type="datetime-local" />}
     @post.written_on = nil
-    assert_deprecated do
-      assert_dom_equal(expected, datetime_field("post", "written_on"))
-    end
+    assert_dom_equal(expected, datetime_field("post", "written_on"))
   end
 
   def test_datetime_field_with_string_values_for_min_and_max
-    expected = %{<input id="post_written_on" max="2010-08-15T10:25:00.000+0000" min="2000-06-15T20:45:30.000+0000" name="post[written_on]" type="datetime" value="2004-06-15T01:02:03.000+0000" />}
+    expected = %{<input id="post_written_on" max="2010-08-15T10:25:00" min="2000-06-15T20:45:30" name="post[written_on]" type="datetime-local" value="2004-06-15T01:02:03" />}
     @post.written_on = DateTime.new(2004, 6, 15, 1, 2, 3)
-    min_value = "2000-06-15T20:45:30.000+0000"
-    max_value = "2010-08-15T10:25:00.000+0000"
-    assert_deprecated do
-      assert_dom_equal(expected, datetime_field("post", "written_on", min: min_value, max: max_value))
-    end
+    min_value = "2000-06-15T20:45:30"
+    max_value = "2010-08-15T10:25:00"
+    assert_dom_equal(expected, datetime_field("post", "written_on", min: min_value, max: max_value))
   end
 
   def test_datetime_field_with_invalid_string_values_for_min_and_max
-    expected = %{<input id="post_written_on" name="post[written_on]" type="datetime" value="2004-06-15T01:02:03.000+0000" />}
+    expected = %{<input id="post_written_on" name="post[written_on]" type="datetime-local" value="2004-06-15T01:02:03" />}
     @post.written_on = DateTime.new(2004, 6, 15, 1, 2, 3)
     min_value = "foo"
     max_value = "bar"
-    assert_deprecated do
-      assert_dom_equal(expected, datetime_field("post", "written_on", min: min_value, max: max_value))
-    end
+    assert_dom_equal(expected, datetime_field("post", "written_on", min: min_value, max: max_value))
   end
 
   def test_datetime_local_field
@@ -1215,52 +1213,6 @@ class FormHelperTest < ActionView::TestCase
     assert_dom_equal(expected, datetime_local_field("post", "written_on"))
   end
 
-  def test_datetime_local_field_with_datetime_value
-    expected = %{<input id="post_written_on" name="post[written_on]" type="datetime-local" value="2004-06-15T01:02:03" />}
-    @post.written_on = DateTime.new(2004, 6, 15, 1, 2, 3)
-    assert_dom_equal(expected, datetime_local_field("post", "written_on"))
-  end
-
-  def test_datetime_local_field_with_extra_attrs
-    expected = %{<input id="post_written_on" step="60" max="2010-08-15T10:25:00" min="2000-06-15T20:45:30" name="post[written_on]" type="datetime-local" value="2004-06-15T01:02:03" />}
-    @post.written_on = DateTime.new(2004, 6, 15, 1, 2, 3)
-    min_value = DateTime.new(2000, 6, 15, 20, 45, 30)
-    max_value = DateTime.new(2010, 8, 15, 10, 25, 00)
-    step = 60
-    assert_dom_equal(expected, datetime_local_field("post", "written_on", min: min_value, max: max_value, step: step))
-  end
-
-  def test_datetime_local_field_with_timewithzone_value
-    previous_time_zone, Time.zone = Time.zone, 'UTC'
-    expected = %{<input id="post_written_on" name="post[written_on]" type="datetime-local" value="2004-06-15T15:30:45" />}
-    @post.written_on = Time.zone.parse('2004-06-15 15:30:45')
-    assert_dom_equal(expected, datetime_local_field("post", "written_on"))
-  ensure
-    Time.zone = previous_time_zone
-  end
-
-  def test_datetime_local_field_with_nil_value
-    expected = %{<input id="post_written_on" name="post[written_on]" type="datetime-local" />}
-    @post.written_on = nil
-    assert_dom_equal(expected, datetime_local_field("post", "written_on"))
-  end
-
-  def test_datetime_local_field_with_string_values_for_min_and_max
-    expected = %{<input id="post_written_on" max="2010-08-15T10:25:00" min="2000-06-15T20:45:30" name="post[written_on]" type="datetime-local" value="2004-06-15T01:02:03" />}
-    @post.written_on = DateTime.new(2004, 6, 15, 1, 2, 3)
-    min_value = "2000-06-15T20:45:30"
-    max_value = "2010-08-15T10:25:00"
-    assert_dom_equal(expected, datetime_local_field("post", "written_on", min: min_value, max: max_value))
-  end
-
-  def test_datetime_local_field_with_invalid_string_values_for_min_and_max
-    expected = %{<input id="post_written_on" name="post[written_on]" type="datetime-local" value="2004-06-15T01:02:03" />}
-    @post.written_on = DateTime.new(2004, 6, 15, 1, 2, 3)
-    min_value = "foo"
-    max_value = "bar"
-    assert_dom_equal(expected, datetime_local_field("post", "written_on", min: min_value, max: max_value))
-  end
-
   def test_month_field
     expected = %{<input id="post_written_on" name="post[written_on]" type="month" value="2004-06" />}
     assert_dom_equal(expected, month_field("post", "written_on"))
@@ -1288,9 +1240,9 @@ class FormHelperTest < ActionView::TestCase
   end
 
   def test_month_field_with_timewithzone_value
-    previous_time_zone, Time.zone = Time.zone, 'UTC'
+    previous_time_zone, Time.zone = Time.zone, "UTC"
     expected = %{<input id="post_written_on" name="post[written_on]" type="month" value="2004-06" />}
-    @post.written_on = Time.zone.parse('2004-06-15 15:30:45')
+    @post.written_on = Time.zone.parse("2004-06-15 15:30:45")
     assert_dom_equal(expected, month_field("post", "written_on"))
   ensure
     Time.zone = previous_time_zone
@@ -1323,9 +1275,9 @@ class FormHelperTest < ActionView::TestCase
   end
 
   def test_week_field_with_timewithzone_value
-    previous_time_zone, Time.zone = Time.zone, 'UTC'
+    previous_time_zone, Time.zone = Time.zone, "UTC"
     expected = %{<input id="post_written_on" name="post[written_on]" type="week" value="2004-W25" />}
-    @post.written_on = Time.zone.parse('2004-06-15 15:30:45')
+    @post.written_on = Time.zone.parse("2004-06-15 15:30:45")
     assert_dom_equal(expected, week_field("post", "written_on"))
   ensure
     Time.zone = previous_time_zone
@@ -1434,7 +1386,7 @@ class FormHelperTest < ActionView::TestCase
     )
     assert_dom_equal(
       '<select name="post[secret]"></select>',
-      select("post", "secret", [], {}, "id" => nil)
+      select("post", "secret", [], {}, { "id" => nil })
     )
     assert_dom_equal(
       text_field("post", "title", "id" => nil),
@@ -1484,26 +1436,26 @@ class FormHelperTest < ActionView::TestCase
   def test_index_with_nil_id
     assert_dom_equal(
       '<input name="post[5][title]" type="text" value="Hello World" />',
-      text_field("post", "title", "index" => 5, 'id' => nil)
+      text_field("post", "title", "index" => 5, "id" => nil)
     )
     assert_dom_equal(
       %{<textarea name="post[5][body]">\nBack to the hill and over it again!</textarea>},
-      text_area("post", "body", "index" => 5, 'id' => nil)
+      text_area("post", "body", "index" => 5, "id" => nil)
     )
     assert_dom_equal(
       '<input name="post[5][secret]" type="hidden" value="0" /><input checked="checked" name="post[5][secret]" type="checkbox" value="1" />',
-      check_box("post", "secret", "index" => 5, 'id' => nil)
+      check_box("post", "secret", "index" => 5, "id" => nil)
     )
     assert_dom_equal(
-      text_field("post", "title", "index" => 5, 'id' => nil),
+      text_field("post", "title", "index" => 5, "id" => nil),
       text_field("post", "title", index: 5, id: nil)
     )
     assert_dom_equal(
-      text_area("post", "body", "index" => 5, 'id' => nil),
+      text_area("post", "body", "index" => 5, "id" => nil),
       text_area("post", "body", index: 5, id: nil)
     )
     assert_dom_equal(
-      check_box("post", "secret", "index" => 5, 'id' => nil),
+      check_box("post", "secret", "index" => 5, "id" => nil),
       check_box("post", "secret", index: 5, id: nil)
     )
   end
@@ -1516,7 +1468,7 @@ class FormHelperTest < ActionView::TestCase
     )
     assert_dom_equal(
       %{<input id="post_#{pid}_title" name="post[#{pid}][title]" type="text" value="Hello World" />},
-      text_field("post[]","title")
+      text_field("post[]", "title")
     )
     assert_dom_equal(
       %{<textarea id="post_#{pid}_body" name="post[#{pid}][body]">\nBack to the hill and over it again!</textarea>},
@@ -1526,10 +1478,10 @@ class FormHelperTest < ActionView::TestCase
       %{<input name="post[#{pid}][secret]" type="hidden" value="0" /><input checked="checked" id="post_#{pid}_secret" name="post[#{pid}][secret]" type="checkbox" value="1" />},
       check_box("post[]", "secret")
     )
-   assert_dom_equal(
+    assert_dom_equal(
       %{<input checked="checked" id="post_#{pid}_title_hello_world" name="post[#{pid}][title]" type="radio" value="Hello World" />},
       radio_button("post[]", "title", "Hello World")
-    )
+     )
     assert_dom_equal(
       %{<input id="post_#{pid}_title_goodbye_world" name="post[#{pid}][title]" type="radio" value="Goodbye World" />},
       radio_button("post[]", "title", "Goodbye World")
@@ -1550,10 +1502,10 @@ class FormHelperTest < ActionView::TestCase
       %{<input name="post[#{pid}][secret]" type="hidden" value="0" /><input checked="checked" name="post[#{pid}][secret]" type="checkbox" value="1" />},
       check_box("post[]", "secret", id: nil)
     )
-   assert_dom_equal(
-     %{<input checked="checked" name="post[#{pid}][title]" type="radio" value="Hello World" />},
-      radio_button("post[]", "title", "Hello World", id: nil)
-    )
+    assert_dom_equal(
+      %{<input checked="checked" name="post[#{pid}][title]" type="radio" value="Hello World" />},
+       radio_button("post[]", "title", "Hello World", id: nil)
+     )
     assert_dom_equal(
       %{<input name="post[#{pid}][title]" type="radio" value="Goodbye World" />},
       radio_button("post[]", "title", "Goodbye World", id: nil)
@@ -1562,50 +1514,82 @@ class FormHelperTest < ActionView::TestCase
 
   def test_form_for_requires_block
     error = assert_raises(ArgumentError) do
-      form_for(@post, html: { id: 'create-post' })
+      form_for(@post, html: { id: "create-post" })
     end
     assert_equal "Missing block", error.message
   end
 
   def test_form_for_requires_arguments
     error = assert_raises(ArgumentError) do
-      form_for(nil, html: { id: 'create-post' }) do
+      form_for(nil, html: { id: "create-post" }) do
       end
     end
     assert_equal "First argument in form cannot contain nil or be empty", error.message
 
     error = assert_raises(ArgumentError) do
-      form_for([nil, nil], html: { id: 'create-post' }) do
+      form_for([nil, nil], html: { id: "create-post" }) do
       end
     end
     assert_equal "First argument in form cannot contain nil or be empty", error.message
   end
 
   def test_form_for
-    form_for(@post, html: { id: 'create-post' }) do |f|
+    form_for(@post, html: { id: "create-post" }) do |f|
+      concat f.label(:title) { "The Title" }
+      concat f.text_field(:title)
+      concat f.text_area(:body)
+      concat f.check_box(:secret)
+      concat f.submit("Create post")
+      concat f.button("Create post")
+      concat f.button {
+        concat content_tag(:span, "Create post")
+      }
+    end
+
+    expected = whole_form("/posts/123", "create-post", "edit_post", method: "patch") do
+      "<label for='post_title'>The Title</label>" \
+      "<input name='post[title]' type='text' id='post_title' value='Hello World' />" \
+      "<textarea name='post[body]' id='post_body'>\nBack to the hill and over it again!</textarea>" \
+      "<input name='post[secret]' type='hidden' value='0' />" \
+      "<input name='post[secret]' checked='checked' type='checkbox' id='post_secret' value='1' />" \
+      "<input name='commit' data-disable-with='Create post' type='submit' value='Create post' />" \
+      "<button name='button' type='submit'>Create post</button>" \
+      "<button name='button' type='submit'><span>Create post</span></button>"
+    end
+
+    assert_dom_equal expected, output_buffer
+  end
+
+  def test_form_for_is_not_affected_by_form_with_generates_ids
+    old_value = ActionView::Helpers::FormHelper.form_with_generates_ids
+    ActionView::Helpers::FormHelper.form_with_generates_ids = false
+
+    form_for(@post, html: { id: "create-post" }) do |f|
       concat f.label(:title) { "The Title" }
       concat f.text_field(:title)
       concat f.text_area(:body)
       concat f.check_box(:secret)
-      concat f.submit('Create post')
-      concat f.button('Create post')
+      concat f.submit("Create post")
+      concat f.button("Create post")
       concat f.button {
-        concat content_tag(:span, 'Create post')
+        concat content_tag(:span, "Create post")
       }
     end
 
     expected = whole_form("/posts/123", "create-post", "edit_post", method: "patch") do
-      "<label for='post_title'>The Title</label>" +
-      "<input name='post[title]' type='text' id='post_title' value='Hello World' />" +
-      "<textarea name='post[body]' id='post_body'>\nBack to the hill and over it again!</textarea>" +
-      "<input name='post[secret]' type='hidden' value='0' />" +
-      "<input name='post[secret]' checked='checked' type='checkbox' id='post_secret' value='1' />" +
-      "<input name='commit' data-disable-with='Create post' type='submit' value='Create post' />" +
-      "<button name='button' type='submit'>Create post</button>" +
+      "<label for='post_title'>The Title</label>" \
+      "<input name='post[title]' type='text' id='post_title' value='Hello World' />" \
+      "<textarea name='post[body]' id='post_body'>\nBack to the hill and over it again!</textarea>" \
+      "<input name='post[secret]' type='hidden' value='0' />" \
+      "<input name='post[secret]' checked='checked' type='checkbox' id='post_secret' value='1' />" \
+      "<input name='commit' data-disable-with='Create post' type='submit' value='Create post' />" \
+      "<button name='button' type='submit'>Create post</button>" \
       "<button name='button' type='submit'><span>Create post</span></button>"
     end
 
     assert_dom_equal expected, output_buffer
+  ensure
+    ActionView::Helpers::FormHelper.form_with_generates_ids = old_value
   end
 
   def test_form_for_with_collection_radio_buttons
@@ -1616,10 +1600,10 @@ class FormHelperTest < ActionView::TestCase
     end
 
     expected = whole_form("/posts", "new_post", "new_post") do
-      "<input type='hidden' name='post[active]' value='' />" +
-      "<input id='post_active_true' name='post[active]' type='radio' value='true' />" +
-      "<label for='post_active_true'>true</label>" +
-      "<input checked='checked' id='post_active_false' name='post[active]' type='radio' value='false' />" +
+      "<input type='hidden' name='post[active]' value='' />" \
+      "<input id='post_active_true' name='post[active]' type='radio' value='true' />" \
+      "<label for='post_active_true'>true</label>" \
+      "<input checked='checked' id='post_active_false' name='post[active]' type='radio' value='false' />" \
       "<label for='post_active_false'>false</label>"
     end
 
@@ -1638,12 +1622,12 @@ class FormHelperTest < ActionView::TestCase
     end
 
     expected = whole_form("/posts", "new_post", "new_post") do
-      "<input type='hidden' name='post[active]' value='' />" +
-      "<label for='post_active_true'>"+
-      "<input id='post_active_true' name='post[active]' type='radio' value='true' />" +
-      "true</label>" +
-      "<label for='post_active_false'>"+
-      "<input checked='checked' id='post_active_false' name='post[active]' type='radio' value='false' />" +
+      "<input type='hidden' name='post[active]' value='' />" \
+      "<label for='post_active_true'>" \
+      "<input id='post_active_true' name='post[active]' type='radio' value='true' />" \
+      "true</label>" \
+      "<label for='post_active_false'>" \
+      "<input checked='checked' id='post_active_false' name='post[active]' type='radio' value='false' />" \
       "false</label>"
     end
 
@@ -1664,13 +1648,13 @@ class FormHelperTest < ActionView::TestCase
     end
 
     expected = whole_form("/posts", "new_post_1", "new_post") do
-      "<input type='hidden' name='post[active]' value='' />" +
-      "<label for='post_active_true'>"+
-      "<input id='post_active_true' name='post[active]' type='radio' value='true' />" +
-      "true</label>" +
-      "<label for='post_active_false'>"+
-      "<input checked='checked' id='post_active_false' name='post[active]' type='radio' value='false' />" +
-      "false</label>"+
+      "<input type='hidden' name='post[active]' value='' />" \
+      "<label for='post_active_true'>" \
+      "<input id='post_active_true' name='post[active]' type='radio' value='true' />" \
+      "true</label>" \
+      "<label for='post_active_false'>" \
+      "<input checked='checked' id='post_active_false' name='post[active]' type='radio' value='false' />" \
+      "false</label>" \
       "<input id='post_id' name='post[id]' type='hidden' value='1' />"
     end
 
@@ -1681,15 +1665,15 @@ class FormHelperTest < ActionView::TestCase
     post = Post.new
     def post.active; false; end
 
-    form_for(post, namespace: 'foo') do |f|
+    form_for(post, namespace: "foo") do |f|
       concat f.collection_radio_buttons(:active, [true, false], :to_s, :to_s)
     end
 
     expected = whole_form("/posts", "foo_new_post", "new_post") do
-      "<input type='hidden' name='post[active]' value='' />" +
-      "<input id='foo_post_active_true' name='post[active]' type='radio' value='true' />" +
-      "<label for='foo_post_active_true'>true</label>" +
-      "<input checked='checked' id='foo_post_active_false' name='post[active]' type='radio' value='false' />" +
+      "<input type='hidden' name='post[active]' value='' />" \
+      "<input id='foo_post_active_true' name='post[active]' type='radio' value='true' />" \
+      "<label for='foo_post_active_true'>true</label>" \
+      "<input checked='checked' id='foo_post_active_false' name='post[active]' type='radio' value='false' />" \
       "<label for='foo_post_active_false'>false</label>"
     end
 
@@ -1700,15 +1684,15 @@ class FormHelperTest < ActionView::TestCase
     post = Post.new
     def post.active; false; end
 
-    form_for(post, index: '1') do |f|
+    form_for(post, index: "1") do |f|
       concat f.collection_radio_buttons(:active, [true, false], :to_s, :to_s)
     end
 
     expected = whole_form("/posts", "new_post", "new_post") do
-      "<input type='hidden' name='post[1][active]' value='' />" +
-      "<input id='post_1_active_true' name='post[1][active]' type='radio' value='true' />" +
-      "<label for='post_1_active_true'>true</label>" +
-      "<input checked='checked' id='post_1_active_false' name='post[1][active]' type='radio' value='false' />" +
+      "<input type='hidden' name='post[1][active]' value='' />" \
+      "<input id='post_1_active_true' name='post[1][active]' type='radio' value='true' />" \
+      "<label for='post_1_active_true'>true</label>" \
+      "<input checked='checked' id='post_1_active_false' name='post[1][active]' type='radio' value='false' />" \
       "<label for='post_1_active_false'>false</label>"
     end
 
@@ -1724,12 +1708,12 @@ class FormHelperTest < ActionView::TestCase
     end
 
     expected = whole_form("/posts", "new_post", "new_post") do
-      "<input name='post[tag_ids][]' type='hidden' value='' />" +
-      "<input checked='checked' id='post_tag_ids_1' name='post[tag_ids][]' type='checkbox' value='1' />" +
-      "<label for='post_tag_ids_1'>Tag 1</label>" +
-      "<input id='post_tag_ids_2' name='post[tag_ids][]' type='checkbox' value='2' />" +
-      "<label for='post_tag_ids_2'>Tag 2</label>" +
-      "<input checked='checked' id='post_tag_ids_3' name='post[tag_ids][]' type='checkbox' value='3' />" +
+      "<input name='post[tag_ids][]' type='hidden' value='' />" \
+      "<input checked='checked' id='post_tag_ids_1' name='post[tag_ids][]' type='checkbox' value='1' />" \
+      "<label for='post_tag_ids_1'>Tag 1</label>" \
+      "<input id='post_tag_ids_2' name='post[tag_ids][]' type='checkbox' value='2' />" \
+      "<label for='post_tag_ids_2'>Tag 2</label>" \
+      "<input checked='checked' id='post_tag_ids_3' name='post[tag_ids][]' type='checkbox' value='3' />" \
       "<label for='post_tag_ids_3'>Tag 3</label>"
     end
 
@@ -1748,15 +1732,15 @@ class FormHelperTest < ActionView::TestCase
     end
 
     expected = whole_form("/posts", "new_post", "new_post") do
-      "<input name='post[tag_ids][]' type='hidden' value='' />" +
-      "<label for='post_tag_ids_1'>" +
-      "<input checked='checked' id='post_tag_ids_1' name='post[tag_ids][]' type='checkbox' value='1' />" +
-      "Tag 1</label>" +
-      "<label for='post_tag_ids_2'>" +
-      "<input id='post_tag_ids_2' name='post[tag_ids][]' type='checkbox' value='2' />" +
-      "Tag 2</label>" +
-      "<label for='post_tag_ids_3'>" +
-      "<input checked='checked' id='post_tag_ids_3' name='post[tag_ids][]' type='checkbox' value='3' />" +
+      "<input name='post[tag_ids][]' type='hidden' value='' />" \
+      "<label for='post_tag_ids_1'>" \
+      "<input checked='checked' id='post_tag_ids_1' name='post[tag_ids][]' type='checkbox' value='1' />" \
+      "Tag 1</label>" \
+      "<label for='post_tag_ids_2'>" \
+      "<input id='post_tag_ids_2' name='post[tag_ids][]' type='checkbox' value='2' />" \
+      "Tag 2</label>" \
+      "<label for='post_tag_ids_3'>" \
+      "<input checked='checked' id='post_tag_ids_3' name='post[tag_ids][]' type='checkbox' value='3' />" \
       "Tag 3</label>"
     end
 
@@ -1778,16 +1762,16 @@ class FormHelperTest < ActionView::TestCase
     end
 
     expected = whole_form("/posts", "new_post_1", "new_post") do
-      "<input name='post[tag_ids][]' type='hidden' value='' />"+
-      "<label for='post_tag_ids_1'>" +
-      "<input checked='checked' id='post_tag_ids_1' name='post[tag_ids][]' type='checkbox' value='1' />" +
-      "Tag 1</label>" +
-      "<label for='post_tag_ids_2'>" +
-      "<input id='post_tag_ids_2' name='post[tag_ids][]' type='checkbox' value='2' />" +
-      "Tag 2</label>" +
-      "<label for='post_tag_ids_3'>" +
-      "<input checked='checked' id='post_tag_ids_3' name='post[tag_ids][]' type='checkbox' value='3' />" +
-      "Tag 3</label>" +
+      "<input name='post[tag_ids][]' type='hidden' value='' />" \
+      "<label for='post_tag_ids_1'>" \
+      "<input checked='checked' id='post_tag_ids_1' name='post[tag_ids][]' type='checkbox' value='1' />" \
+      "Tag 1</label>" \
+      "<label for='post_tag_ids_2'>" \
+      "<input id='post_tag_ids_2' name='post[tag_ids][]' type='checkbox' value='2' />" \
+      "Tag 2</label>" \
+      "<label for='post_tag_ids_3'>" \
+      "<input checked='checked' id='post_tag_ids_3' name='post[tag_ids][]' type='checkbox' value='3' />" \
+      "Tag 3</label>" \
       "<input id='post_id' name='post[id]' type='hidden' value='1' />"
     end
 
@@ -1799,13 +1783,13 @@ class FormHelperTest < ActionView::TestCase
     def post.tag_ids; [1]; end
     collection = [[1, "Tag 1"]]
 
-    form_for(post, namespace: 'foo') do |f|
+    form_for(post, namespace: "foo") do |f|
       concat f.collection_check_boxes(:tag_ids, collection, :first, :last)
     end
 
     expected = whole_form("/posts", "foo_new_post", "new_post") do
-      "<input name='post[tag_ids][]' type='hidden' value='' />" +
-      "<input checked='checked' id='foo_post_tag_ids_1' name='post[tag_ids][]' type='checkbox' value='1' />" +
+      "<input name='post[tag_ids][]' type='hidden' value='' />" \
+      "<input checked='checked' id='foo_post_tag_ids_1' name='post[tag_ids][]' type='checkbox' value='1' />" \
       "<label for='foo_post_tag_ids_1'>Tag 1</label>"
     end
 
@@ -1817,13 +1801,13 @@ class FormHelperTest < ActionView::TestCase
     def post.tag_ids; [1]; end
     collection = [[1, "Tag 1"]]
 
-    form_for(post, index: '1') do |f|
+    form_for(post, index: "1") do |f|
       concat f.collection_check_boxes(:tag_ids, collection, :first, :last)
     end
 
     expected = whole_form("/posts", "new_post", "new_post") do
-      "<input name='post[1][tag_ids][]' type='hidden' value='' />" +
-      "<input checked='checked' id='post_1_tag_ids_1' name='post[1][tag_ids][]' type='checkbox' value='1' />" +
+      "<input name='post[1][tag_ids][]' type='hidden' value='' />" \
+      "<input checked='checked' id='post_1_tag_ids_1' name='post[1][tag_ids][]' type='checkbox' value='1' />" \
       "<label for='post_1_tag_ids_1'>Tag 1</label>"
     end
 
@@ -1831,22 +1815,18 @@ class FormHelperTest < ActionView::TestCase
   end
 
   def test_form_for_with_file_field_generate_multipart
-    Post.send :attr_accessor, :file
-
-    form_for(@post, html: { id: 'create-post' }) do |f|
+    form_for(@post, html: { id: "create-post" }) do |f|
       concat f.file_field(:file)
     end
 
     expected = whole_form("/posts/123", "create-post", "edit_post", method: "patch", multipart: true) do
-      "<input name='post[file]' type='hidden' value='' /><input name='post[file]' type='file' id='post_file' />"
+      "<input name='post[file]' type='file' id='post_file' />"
     end
 
     assert_dom_equal expected, output_buffer
   end
 
   def test_fields_for_with_file_field_generate_multipart
-    Comment.send :attr_accessor, :file
-
     form_for(@post) do |f|
       concat f.fields_for(:comment, @post) { |c|
         concat c.file_field(:file)
@@ -1854,7 +1834,7 @@ class FormHelperTest < ActionView::TestCase
     end
 
     expected = whole_form("/posts/123", "edit_post_123", "edit_post", method: "patch", multipart: true) do
-      "<input name='post[comment][file]' type='hidden' value='' /><input name='post[comment][file]' type='file' id='post_comment_file' />"
+      "<input name='post[comment][file]' type='file' id='post_comment_file' />"
     end
 
     assert_dom_equal expected, output_buffer
@@ -1865,7 +1845,7 @@ class FormHelperTest < ActionView::TestCase
       concat f.label(:title)
     end
 
-    expected = whole_form("/posts/123.json", "edit_post_123", "edit_post", method: 'patch') do
+    expected = whole_form("/posts/123.json", "edit_post_123", "edit_post", method: "patch") do
       "<label for='post_title'>Title</label>"
     end
 
@@ -1877,32 +1857,32 @@ class FormHelperTest < ActionView::TestCase
 
     form_for(blog_post) do |f|
       concat f.text_field :title
-      concat f.submit('Edit post')
+      concat f.submit("Edit post")
     end
 
     expected = whole_form("/posts/44", "edit_post_44", "edit_post", method: "patch") do
-      "<input name='post[title]' type='text' id='post_title' value='And his name will be forty and four.' />" +
+      "<input name='post[title]' type='text' id='post_title' value='And his name will be forty and four.' />" \
       "<input name='commit' data-disable-with='Edit post' type='submit' value='Edit post' />"
     end
 
     assert_dom_equal expected, output_buffer
   end
 
-  def test_form_for_with_symbol_object_name
+  def test_form_for_with_symbol_as
     form_for(@post, as: "other_name", html: { id: "create-post" }) do |f|
-      concat f.label(:title, class: 'post_title')
+      concat f.label(:title, class: "post_title")
       concat f.text_field(:title)
       concat f.text_area(:body)
       concat f.check_box(:secret)
-      concat f.submit('Create post')
+      concat f.submit("Create post")
     end
 
-    expected =  whole_form("/posts/123", "create-post", "edit_other_name", method: "patch") do
-      "<label for='other_name_title' class='post_title'>Title</label>" +
-      "<input name='other_name[title]' id='other_name_title' value='Hello World' type='text' />" +
-      "<textarea name='other_name[body]' id='other_name_body'>\nBack to the hill and over it again!</textarea>" +
-      "<input name='other_name[secret]' value='0' type='hidden' />" +
-      "<input name='other_name[secret]' checked='checked' id='other_name_secret' value='1' type='checkbox' />" +
+    expected = whole_form("/posts/123", "create-post", "edit_other_name", method: "patch") do
+      "<label for='other_name_title' class='post_title'>Title</label>" \
+      "<input name='other_name[title]' id='other_name_title' value='Hello World' type='text' />" \
+      "<textarea name='other_name[body]' id='other_name_body'>\nBack to the hill and over it again!</textarea>" \
+      "<input name='other_name[secret]' value='0' type='hidden' />" \
+      "<input name='other_name[secret]' checked='checked' id='other_name_secret' value='1' type='checkbox' />" \
       "<input name='commit' value='Create post' data-disable-with='Create post' type='submit' />"
     end
 
@@ -1913,27 +1893,27 @@ class FormHelperTest < ActionView::TestCase
     obj = Class.new do
       private
 
-      def private_property
-        raise "This method should not be called."
-      end
+        def private_property
+          raise "This method should not be called."
+        end
     end.new
 
-    form_for(obj, as: "other_name", url: '/', html: { id: "edit-other-name" }) do |f|
+    form_for(obj, as: "other_name", url: "/", html: { id: "edit-other-name" }) do |f|
       assert_raise(NoMethodError) { f.hidden_field(:private_property) }
     end
   end
 
   def test_form_for_with_method_as_part_of_html_options
-    form_for(@post, url: '/', html: { id: 'create-post', method: :delete }) do |f|
+    form_for(@post, url: "/", html: { id: "create-post", method: :delete }) do |f|
       concat f.text_field(:title)
       concat f.text_area(:body)
       concat f.check_box(:secret)
     end
 
-    expected =  whole_form("/", "create-post", "edit_post", method: "delete") do
-      "<input name='post[title]' type='text' id='post_title' value='Hello World' />" +
-      "<textarea name='post[body]' id='post_body'>\nBack to the hill and over it again!</textarea>" +
-      "<input name='post[secret]' type='hidden' value='0' />" +
+    expected = whole_form("/", "create-post", "edit_post", method: "delete") do
+      "<input name='post[title]' type='text' id='post_title' value='Hello World' />" \
+      "<textarea name='post[body]' id='post_body'>\nBack to the hill and over it again!</textarea>" \
+      "<input name='post[secret]' type='hidden' value='0' />" \
       "<input name='post[secret]' checked='checked' type='checkbox' id='post_secret' value='1' />"
     end
 
@@ -1941,16 +1921,16 @@ class FormHelperTest < ActionView::TestCase
   end
 
   def test_form_for_with_method
-    form_for(@post, url: '/', method: :delete, html: { id: 'create-post' }) do |f|
+    form_for(@post, url: "/", method: :delete, html: { id: "create-post" }) do |f|
       concat f.text_field(:title)
       concat f.text_area(:body)
       concat f.check_box(:secret)
     end
 
-    expected =  whole_form("/", "create-post", "edit_post", method: "delete") do
-      "<input name='post[title]' type='text' id='post_title' value='Hello World' />" +
-      "<textarea name='post[body]' id='post_body'>\nBack to the hill and over it again!</textarea>" +
-      "<input name='post[secret]' type='hidden' value='0' />" +
+    expected = whole_form("/", "create-post", "edit_post", method: "delete") do
+      "<input name='post[title]' type='text' id='post_title' value='Hello World' />" \
+      "<textarea name='post[body]' id='post_body'>\nBack to the hill and over it again!</textarea>" \
+      "<input name='post[secret]' type='hidden' value='0' />" \
       "<input name='post[secret]' checked='checked' type='checkbox' id='post_secret' value='1' />"
     end
 
@@ -1964,7 +1944,7 @@ class FormHelperTest < ActionView::TestCase
       concat f.search_field(:title)
     end
 
-    expected =  whole_form("/search", "search-post", "new_post", method: "get") do
+    expected = whole_form("/search", "search-post", "new_post", method: "get") do
       "<input name='post[title]' type='search' id='post_title' />"
     end
 
@@ -1972,16 +1952,16 @@ class FormHelperTest < ActionView::TestCase
   end
 
   def test_form_for_with_remote
-    form_for(@post, url: '/', remote: true, html: { id: 'create-post', method: :patch }) do |f|
+    form_for(@post, url: "/", remote: true, html: { id: "create-post", method: :patch }) do |f|
       concat f.text_field(:title)
       concat f.text_area(:body)
       concat f.check_box(:secret)
     end
 
-    expected =  whole_form("/", "create-post", "edit_post", method: "patch", remote: true) do
-      "<input name='post[title]' type='text' id='post_title' value='Hello World' />" +
-      "<textarea name='post[body]' id='post_body'>\nBack to the hill and over it again!</textarea>" +
-      "<input name='post[secret]' type='hidden' value='0' />" +
+    expected = whole_form("/", "create-post", "edit_post", method: "patch", remote: true) do
+      "<input name='post[title]' type='text' id='post_title' value='Hello World' />" \
+      "<textarea name='post[body]' id='post_body'>\nBack to the hill and over it again!</textarea>" \
+      "<input name='post[secret]' type='hidden' value='0' />" \
       "<input name='post[secret]' checked='checked' type='checkbox' id='post_secret' value='1' />"
     end
 
@@ -2013,16 +1993,16 @@ class FormHelperTest < ActionView::TestCase
   end
 
   def test_form_for_with_remote_in_html
-    form_for(@post, url: '/', html: { remote: true, id: 'create-post', method: :patch }) do |f|
+    form_for(@post, url: "/", html: { remote: true, id: "create-post", method: :patch }) do |f|
       concat f.text_field(:title)
       concat f.text_area(:body)
       concat f.check_box(:secret)
     end
 
-    expected =  whole_form("/", "create-post", "edit_post", method: "patch", remote: true) do
-      "<input name='post[title]' type='text' id='post_title' value='Hello World' />" +
-      "<textarea name='post[body]' id='post_body'>\nBack to the hill and over it again!</textarea>" +
-      "<input name='post[secret]' type='hidden' value='0' />" +
+    expected = whole_form("/", "create-post", "edit_post", method: "patch", remote: true) do
+      "<input name='post[title]' type='text' id='post_title' value='Hello World' />" \
+      "<textarea name='post[body]' id='post_body'>\nBack to the hill and over it again!</textarea>" \
+      "<input name='post[secret]' type='hidden' value='0' />" \
       "<input name='post[secret]' checked='checked' type='checkbox' id='post_secret' value='1' />"
     end
 
@@ -2038,10 +2018,10 @@ class FormHelperTest < ActionView::TestCase
         concat f.check_box(:secret)
       end
 
-      expected =  whole_form("/posts", "new_post", "new_post", remote: true) do
-        "<input name='post[title]' type='text' id='post_title' value='Hello World' />" +
-        "<textarea name='post[body]' id='post_body'>\nBack to the hill and over it again!</textarea>" +
-        "<input name='post[secret]' type='hidden' value='0' />" +
+      expected = whole_form("/posts", "new_post", "new_post", remote: true) do
+        "<input name='post[title]' type='text' id='post_title' value='Hello World' />" \
+        "<textarea name='post[body]' id='post_body'>\nBack to the hill and over it again!</textarea>" \
+        "<input name='post[secret]' type='hidden' value='0' />" \
         "<input name='post[secret]' checked='checked' type='checkbox' id='post_secret' value='1' />"
       end
 
@@ -2050,16 +2030,16 @@ class FormHelperTest < ActionView::TestCase
   end
 
   def test_form_for_without_object
-    form_for(:post, html: { id: 'create-post' }) do |f|
+    form_for(:post, html: { id: "create-post" }) do |f|
       concat f.text_field(:title)
       concat f.text_area(:body)
       concat f.check_box(:secret)
     end
 
     expected = whole_form("/", "create-post") do
-      "<input name='post[title]' type='text' id='post_title' value='Hello World' />" +
-      "<textarea name='post[body]' id='post_body'>\nBack to the hill and over it again!</textarea>" +
-      "<input name='post[secret]' type='hidden' value='0' />" +
+      "<input name='post[title]' type='text' id='post_title' value='Hello World' />" \
+      "<textarea name='post[body]' id='post_body'>\nBack to the hill and over it again!</textarea>" \
+      "<input name='post[secret]' type='hidden' value='0' />" \
       "<input name='post[secret]' checked='checked' type='checkbox' id='post_secret' value='1' />"
     end
 
@@ -2074,11 +2054,11 @@ class FormHelperTest < ActionView::TestCase
       concat f.check_box(:secret)
     end
 
-    expected = whole_form('/posts/123', 'edit_post[]', 'edit_post[]', method: 'patch') do
-      "<label for='post_123_title'>Title</label>" +
-      "<input name='post[123][title]' type='text' id='post_123_title' value='Hello World' />" +
-      "<textarea name='post[123][body]' id='post_123_body'>\nBack to the hill and over it again!</textarea>" +
-      "<input name='post[123][secret]' type='hidden' value='0' />" +
+    expected = whole_form("/posts/123", "edit_post[]", "edit_post[]", method: "patch") do
+      "<label for='post_123_title'>Title</label>" \
+      "<input name='post[123][title]' type='text' id='post_123_title' value='Hello World' />" \
+      "<textarea name='post[123][body]' id='post_123_body'>\nBack to the hill and over it again!</textarea>" \
+      "<input name='post[123][secret]' type='hidden' value='0' />" \
       "<input name='post[123][secret]' checked='checked' type='checkbox' id='post_123_secret' value='1' />"
     end
 
@@ -2092,10 +2072,10 @@ class FormHelperTest < ActionView::TestCase
       concat f.check_box(:secret)
     end
 
-    expected = whole_form('/posts/123', 'edit_post[]', 'edit_post[]', method: 'patch') do
-      "<input name='post[][title]' type='text' id='post__title' value='Hello World' />" +
-      "<textarea name='post[][body]' id='post__body'>\nBack to the hill and over it again!</textarea>" +
-      "<input name='post[][secret]' type='hidden' value='0' />" +
+    expected = whole_form("/posts/123", "edit_post[]", "edit_post[]", method: "patch") do
+      "<input name='post[][title]' type='text' id='post__title' value='Hello World' />" \
+      "<textarea name='post[][body]' id='post__body'>\nBack to the hill and over it again!</textarea>" \
+      "<input name='post[][secret]' type='hidden' value='0' />" \
       "<input name='post[][secret]' checked='checked' type='checkbox' id='post__secret' value='1' />"
     end
 
@@ -2104,14 +2084,14 @@ class FormHelperTest < ActionView::TestCase
 
   def test_form_for_label_error_wrapping
     form_for(@post) do |f|
-      concat f.label(:author_name, class: 'label')
+      concat f.label(:author_name, class: "label")
       concat f.text_field(:author_name)
-      concat f.submit('Create post')
+      concat f.submit("Create post")
     end
 
-    expected = whole_form('/posts/123', 'edit_post_123', 'edit_post', method: 'patch') do
-      "<div class='field_with_errors'><label for='post_author_name' class='label'>Author name</label></div>" +
-      "<div class='field_with_errors'><input name='post[author_name]' type='text' id='post_author_name' value='' /></div>" +
+    expected = whole_form("/posts/123", "edit_post_123", "edit_post", method: "patch") do
+      "<div class='field_with_errors'><label for='post_author_name' class='label'>Author name</label></div>" \
+      "<div class='field_with_errors'><input name='post[author_name]' type='text' id='post_author_name' value='' /></div>" \
       "<input name='commit' data-disable-with='Create post' type='submit' value='Create post' />"
     end
 
@@ -2122,14 +2102,14 @@ class FormHelperTest < ActionView::TestCase
     post = remove_instance_variable :@post
 
     form_for(post) do |f|
-      concat f.label(:author_name, class: 'label')
+      concat f.label(:author_name, class: "label")
       concat f.text_field(:author_name)
-      concat f.submit('Create post')
+      concat f.submit("Create post")
     end
 
-    expected = whole_form('/posts/123', 'edit_post_123', 'edit_post', method: 'patch') do
-      "<div class='field_with_errors'><label for='post_author_name' class='label'>Author name</label></div>" +
-      "<div class='field_with_errors'><input name='post[author_name]' type='text' id='post_author_name' value='' /></div>" +
+    expected = whole_form("/posts/123", "edit_post_123", "edit_post", method: "patch") do
+      "<div class='field_with_errors'><label for='post_author_name' class='label'>Author name</label></div>" \
+      "<div class='field_with_errors'><input name='post[author_name]' type='text' id='post_author_name' value='' /></div>" \
       "<input name='commit' data-disable-with='Create post' type='submit' value='Create post' />"
     end
 
@@ -2138,12 +2118,12 @@ class FormHelperTest < ActionView::TestCase
 
   def test_form_for_label_error_wrapping_block_and_non_block_versions
     form_for(@post) do |f|
-      concat f.label(:author_name, 'Name', class: 'label')
-      concat f.label(:author_name, class: 'label') { 'Name' }
+      concat f.label(:author_name, "Name", class: "label")
+      concat f.label(:author_name, class: "label") { "Name" }
     end
 
-    expected = whole_form('/posts/123', 'edit_post_123', 'edit_post', method: 'patch') do
-      "<div class='field_with_errors'><label for='post_author_name' class='label'>Name</label></div>" +
+    expected = whole_form("/posts/123", "edit_post_123", "edit_post", method: "patch") do
+      "<div class='field_with_errors'><label for='post_author_name' class='label'>Name</label></div>" \
       "<div class='field_with_errors'><label for='post_author_name' class='label'>Name</label></div>"
     end
 
@@ -2151,16 +2131,16 @@ class FormHelperTest < ActionView::TestCase
   end
 
   def test_form_for_with_namespace
-    form_for(@post, namespace: 'namespace') do |f|
+    form_for(@post, namespace: "namespace") do |f|
       concat f.text_field(:title)
       concat f.text_area(:body)
       concat f.check_box(:secret)
     end
 
-    expected = whole_form('/posts/123', 'namespace_edit_post_123', 'edit_post', method: 'patch') do
-      "<input name='post[title]' type='text' id='namespace_post_title' value='Hello World' />" +
-      "<textarea name='post[body]' id='namespace_post_body'>\nBack to the hill and over it again!</textarea>" +
-      "<input name='post[secret]' type='hidden' value='0' />" +
+    expected = whole_form("/posts/123", "namespace_edit_post_123", "edit_post", method: "patch") do
+      "<input name='post[title]' type='text' id='namespace_post_title' value='Hello World' />" \
+      "<textarea name='post[body]' id='namespace_post_body'>\nBack to the hill and over it again!</textarea>" \
+      "<input name='post[secret]' type='hidden' value='0' />" \
       "<input name='post[secret]' checked='checked' type='checkbox' id='namespace_post_secret' value='1' />"
     end
 
@@ -2168,21 +2148,21 @@ class FormHelperTest < ActionView::TestCase
   end
 
   def test_form_for_with_namespace_with_date_select
-    form_for(@post, namespace: 'namespace') do |f|
+    form_for(@post, namespace: "namespace") do |f|
       concat f.date_select(:written_on)
     end
 
-    assert_select 'select#namespace_post_written_on_1i'
+    assert_select "select#namespace_post_written_on_1i"
   end
 
   def test_form_for_with_namespace_with_label
-    form_for(@post, namespace: 'namespace') do |f|
+    form_for(@post, namespace: "namespace") do |f|
       concat f.label(:title)
       concat f.text_field(:title)
     end
 
-    expected = whole_form('/posts/123', 'namespace_edit_post_123', 'edit_post', method: 'patch') do
-      "<label for='namespace_post_title'>Title</label>" +
+    expected = whole_form("/posts/123", "namespace_edit_post_123", "edit_post", method: "patch") do
+      "<label for='namespace_post_title'>Title</label>" \
       "<input name='post[title]' type='text' id='namespace_post_title' value='Hello World' />"
     end
 
@@ -2190,11 +2170,11 @@ class FormHelperTest < ActionView::TestCase
   end
 
   def test_form_for_with_namespace_and_as_option
-    form_for(@post, namespace: 'namespace', as: 'custom_name') do |f|
+    form_for(@post, namespace: "namespace", as: "custom_name") do |f|
       concat f.text_field(:title)
     end
 
-    expected = whole_form('/posts/123', 'namespace_edit_custom_name', 'edit_custom_name', method: 'patch') do
+    expected = whole_form("/posts/123", "namespace_edit_custom_name", "edit_custom_name", method: "patch") do
       "<input id='namespace_custom_name_title' name='custom_name[title]' type='text' value='Hello World' />"
     end
 
@@ -2202,25 +2182,25 @@ class FormHelperTest < ActionView::TestCase
   end
 
   def test_two_form_for_with_namespace
-    form_for(@post, namespace: 'namespace_1') do |f|
+    form_for(@post, namespace: "namespace_1") do |f|
       concat f.label(:title)
       concat f.text_field(:title)
     end
 
-    expected_1 = whole_form('/posts/123', 'namespace_1_edit_post_123', 'edit_post', method: 'patch') do
-      "<label for='namespace_1_post_title'>Title</label>" +
+    expected_1 = whole_form("/posts/123", "namespace_1_edit_post_123", "edit_post", method: "patch") do
+      "<label for='namespace_1_post_title'>Title</label>" \
       "<input name='post[title]' type='text' id='namespace_1_post_title' value='Hello World' />"
     end
 
     assert_dom_equal expected_1, output_buffer
 
-    form_for(@post, namespace: 'namespace_2') do |f|
+    form_for(@post, namespace: "namespace_2") do |f|
       concat f.label(:title)
       concat f.text_field(:title)
     end
 
-    expected_2 = whole_form('/posts/123', 'namespace_2_edit_post_123', 'edit_post', method: 'patch') do
-      "<label for='namespace_2_post_title'>Title</label>" +
+    expected_2 = whole_form("/posts/123", "namespace_2_edit_post_123", "edit_post", method: "patch") do
+      "<label for='namespace_2_post_title'>Title</label>" \
       "<input name='post[title]' type='text' id='namespace_2_post_title' value='Hello World' />"
     end
 
@@ -2228,8 +2208,8 @@ class FormHelperTest < ActionView::TestCase
   end
 
   def test_fields_for_with_namespace
-    @comment.body = 'Hello World'
-    form_for(@post, namespace: 'namespace') do |f|
+    @comment.body = "Hello World"
+    form_for(@post, namespace: "namespace") do |f|
       concat f.text_field(:title)
       concat f.text_area(:body)
       concat f.fields_for(@comment) { |c|
@@ -2237,9 +2217,9 @@ class FormHelperTest < ActionView::TestCase
       }
     end
 
-    expected = whole_form('/posts/123', 'namespace_edit_post_123', 'edit_post', method: 'patch') do
-      "<input name='post[title]' type='text' id='namespace_post_title' value='Hello World' />" +
-      "<textarea name='post[body]' id='namespace_post_body'>\nBack to the hill and over it again!</textarea>" +
+    expected = whole_form("/posts/123", "namespace_edit_post_123", "edit_post", method: "patch") do
+      "<input name='post[title]' type='text' id='namespace_post_title' value='Hello World' />" \
+      "<textarea name='post[body]' id='namespace_post_body'>\nBack to the hill and over it again!</textarea>" \
       "<input name='post[comment][body]' type='text' id='namespace_post_comment_body' value='Hello World' />"
     end
 
@@ -2254,7 +2234,7 @@ class FormHelperTest < ActionView::TestCase
           concat f.submit
         end
 
-        expected = whole_form('/posts', 'new_post', 'new_post') do
+        expected = whole_form("/posts", "new_post", "new_post") do
           "<input name='commit' data-disable-with='Create Post' type='submit' value='Create Post' />"
         end
 
@@ -2269,8 +2249,8 @@ class FormHelperTest < ActionView::TestCase
         concat f.submit
       end
 
-      expected = whole_form('/posts/123', 'edit_post_123', 'edit_post', method: 'patch') do
-      "<input name='commit' data-disable-with='Confirm Post changes' type='submit' value='Confirm Post changes' />"
+      expected = whole_form("/posts/123", "edit_post_123", "edit_post", method: "patch") do
+        "<input name='commit' data-disable-with='Confirm Post changes' type='submit' value='Confirm Post changes' />"
       end
 
       assert_dom_equal expected, output_buffer
@@ -2284,7 +2264,7 @@ class FormHelperTest < ActionView::TestCase
       end
 
       expected = whole_form do
-      "<input name='commit' class='extra' data-disable-with='Save changes' type='submit' value='Save changes' />"
+        "<input name='commit' class='extra' data-disable-with='Save changes' type='submit' value='Save changes' />"
       end
 
       assert_dom_equal expected, output_buffer
@@ -2297,8 +2277,8 @@ class FormHelperTest < ActionView::TestCase
         concat f.submit
       end
 
-      expected = whole_form('/posts/123', 'edit_another_post', 'edit_another_post', method: 'patch') do
-      "<input name='commit' data-disable-with='Update your Post' type='submit' value='Update your Post' />"
+      expected = whole_form("/posts/123", "edit_another_post", "edit_another_post", method: "patch") do
+        "<input name='commit' data-disable-with='Update your Post' type='submit' value='Update your Post' />"
       end
 
       assert_dom_equal expected, output_buffer
@@ -2306,14 +2286,14 @@ class FormHelperTest < ActionView::TestCase
   end
 
   def test_nested_fields_for
-    @comment.body = 'Hello World'
+    @comment.body = "Hello World"
     form_for(@post) do |f|
       concat f.fields_for(@comment) { |c|
         concat c.text_field(:body)
       }
     end
 
-    expected = whole_form('/posts/123', 'edit_post_123', 'edit_post', method: 'patch') do
+    expected = whole_form("/posts/123", "edit_post_123", "edit_post", method: "patch") do
       "<input name='post[comment][body]' type='text' id='post_comment_body' value='Hello World' />"
     end
 
@@ -2323,10 +2303,10 @@ class FormHelperTest < ActionView::TestCase
   def test_deep_nested_fields_for
     @comment.save
     form_for(:posts) do |f|
-      f.fields_for('post[]', @post) do |f2|
+      f.fields_for("post[]", @post) do |f2|
         f2.text_field(:id)
         @post.comments.each do |comment|
-          concat f2.fields_for('comment[]', comment) { |c|
+          concat f2.fields_for("comment[]", comment) { |c|
             concat c.text_field(:name)
           }
         end
@@ -2340,18 +2320,19 @@ class FormHelperTest < ActionView::TestCase
     assert_dom_equal expected, output_buffer
   end
 
-
   def test_nested_fields_for_with_nested_collections
-    form_for(@post, as: 'post[]') do |f|
+    form_for(@post, as: "post[]") do |f|
       concat f.text_field(:title)
-      concat f.fields_for('comment[]', @comment) { |c|
+      concat f.fields_for("comment[]", @comment) { |c|
         concat c.text_field(:name)
       }
+      concat f.text_field(:body)
     end
 
-    expected = whole_form('/posts/123', 'edit_post[]', 'edit_post[]', method: 'patch') do
-      "<input name='post[123][title]' type='text' id='post_123_title' value='Hello World' />" +
-      "<input name='post[123][comment][][name]' type='text' id='post_123_comment__name' value='new comment' />"
+    expected = whole_form("/posts/123", "edit_post[]", "edit_post[]", method: "patch") do
+      "<input name='post[123][title]' type='text' id='post_123_title' value='Hello World' />" \
+      "<input name='post[123][comment][][name]' type='text' id='post_123_comment__name' value='new comment' />" \
+      "<input name='post[123][body]' type='text' id='post_123_body' value='Back to the hill and over it again!' />"
     end
 
     assert_dom_equal expected, output_buffer
@@ -2360,13 +2341,13 @@ class FormHelperTest < ActionView::TestCase
   def test_nested_fields_for_with_index_and_parent_fields
     form_for(@post, index: 1) do |c|
       concat c.text_field(:title)
-      concat c.fields_for('comment', @comment, index: 1) { |r|
+      concat c.fields_for("comment", @comment, index: 1) { |r|
         concat r.text_field(:name)
       }
     end
 
-    expected = whole_form('/posts/123', 'edit_post_123', 'edit_post', method: 'patch') do
-      "<input name='post[1][title]' type='text' id='post_1_title' value='Hello World' />" +
+    expected = whole_form("/posts/123", "edit_post_123", "edit_post", method: "patch") do
+      "<input name='post[1][title]' type='text' id='post_1_title' value='Hello World' />" \
       "<input name='post[1][comment][1][name]' type='text' id='post_1_comment_1_name' value='new comment' />"
     end
 
@@ -2380,7 +2361,7 @@ class FormHelperTest < ActionView::TestCase
       }
     end
 
-    expected = whole_form('/posts/123', 'edit_post_123', 'edit_post', method: 'patch') do
+    expected = whole_form("/posts/123", "edit_post_123", "edit_post", method: "patch") do
       "<input name='post[1][comment][title]' type='text' id='post_1_comment_title' value='Hello World' />"
     end
 
@@ -2394,7 +2375,7 @@ class FormHelperTest < ActionView::TestCase
       }
     end
 
-    expected = whole_form('/posts/123', 'edit_post_123', 'edit_post', method: 'patch') do
+    expected = whole_form("/posts/123", "edit_post_123", "edit_post", method: "patch") do
       "<input name='post[1][comment][5][title]' type='text' id='post_1_comment_5_title' value='Hello World' />"
     end
 
@@ -2408,7 +2389,7 @@ class FormHelperTest < ActionView::TestCase
       }
     end
 
-    expected = whole_form('/posts/123', 'edit_post[]', 'edit_post[]', method: 'patch') do
+    expected = whole_form("/posts/123", "edit_post[]", "edit_post[]", method: "patch") do
       "<input name='post[123][comment][title]' type='text' id='post_123_comment_title' value='Hello World' />"
     end
 
@@ -2422,7 +2403,7 @@ class FormHelperTest < ActionView::TestCase
       }
     end
 
-    expected = whole_form('/posts/123', 'edit_post_123', 'edit_post', method: 'patch') do
+    expected = whole_form("/posts/123", "edit_post_123", "edit_post", method: "patch") do
       "<input name='post[comment][5][title]' type='radio' id='post_comment_5_title_hello' value='hello' />"
     end
 
@@ -2436,7 +2417,7 @@ class FormHelperTest < ActionView::TestCase
       }
     end
 
-    expected = whole_form('/posts/123', 'edit_post[]', 'edit_post[]', method: 'patch') do
+    expected = whole_form("/posts/123", "edit_post[]", "edit_post[]", method: "patch") do
       "<input name='post[123][comment][123][title]' type='text' id='post_123_comment_123_title' value='Hello World' />"
     end
 
@@ -2456,9 +2437,9 @@ class FormHelperTest < ActionView::TestCase
       }
     end
 
-    expected = whole_form('/posts/123', 'edit_post[]', 'edit_post[]', method: 'patch') do
+    expected = whole_form("/posts/123", "edit_post[]", "edit_post[]", method: "patch") do
       "<input name='post[123][comment][5][title]' type='text' id='post_123_comment_5_title' value='Hello World' />"
-    end + whole_form('/posts/123', 'edit_post', 'edit_post', method: 'patch') do
+    end + whole_form("/posts/123", "edit_post", "edit_post", method: "patch") do
       "<input name='post[1][comment][123][title]' type='text' id='post_1_comment_123_title' value='Hello World' />"
     end
 
@@ -2475,8 +2456,8 @@ class FormHelperTest < ActionView::TestCase
       }
     end
 
-    expected = whole_form('/posts/123', 'edit_post_123', 'edit_post', method: 'patch') do
-      '<input name="post[title]" type="text" id="post_title" value="Hello World" />' +
+    expected = whole_form("/posts/123", "edit_post_123", "edit_post", method: "patch") do
+      '<input name="post[title]" type="text" id="post_title" value="Hello World" />' \
         '<input id="post_author_attributes_name" name="post[author_attributes][name]" type="text" value="new author" />'
     end
 
@@ -2502,11 +2483,11 @@ class FormHelperTest < ActionView::TestCase
       }
     end
 
-   expected = whole_form('/posts/123', 'edit_post_123', 'edit_post', method: 'patch') do
-     '<input name="post[title]" type="text" id="post_title" value="Hello World" />' +
-     '<input id="post_author_attributes_name" name="post[author_attributes][name]" type="text" value="author #321" />' +
-     '<input id="post_author_attributes_id" name="post[author_attributes][id]" type="hidden" value="321" />'
-   end
+    expected = whole_form("/posts/123", "edit_post_123", "edit_post", method: "patch") do
+      '<input name="post[title]" type="text" id="post_title" value="Hello World" />' \
+      '<input id="post_author_attributes_name" name="post[author_attributes][name]" type="text" value="author #321" />' \
+      '<input id="post_author_attributes_id" name="post[author_attributes][id]" type="hidden" value="321" />'
+    end
 
     assert_dom_equal expected, output_buffer
   end
@@ -2521,9 +2502,9 @@ class FormHelperTest < ActionView::TestCase
       }
     end
 
-    expected = whole_form('/posts/123', 'edit_post_123', 'edit_post', method: 'patch') do
-      '<input name="post[title]" type="text" id="post_title" value="Hello World" />' +
-      '<input id="post_author_attributes_name" name="post[author_attributes][name]" type="text" value="author #321" />' +
+    expected = whole_form("/posts/123", "edit_post_123", "edit_post", method: "patch") do
+      '<input name="post[title]" type="text" id="post_title" value="Hello World" />' \
+      '<input id="post_author_attributes_name" name="post[author_attributes][name]" type="text" value="author #321" />' \
       '<input id="post_author_attributes_id" name="post[author_attributes][id]" type="hidden" value="321" />'
     end
 
@@ -2540,8 +2521,8 @@ class FormHelperTest < ActionView::TestCase
       }
     end
 
-    expected = whole_form('/posts/123', 'edit_post_123', 'edit_post', method: 'patch') do
-      '<input name="post[title]" type="text" id="post_title" value="Hello World" />' +
+    expected = whole_form("/posts/123", "edit_post_123", "edit_post", method: "patch") do
+      '<input name="post[title]" type="text" id="post_title" value="Hello World" />' \
       '<input id="post_author_attributes_name" name="post[author_attributes][name]" type="text" value="author #321" />'
     end
 
@@ -2558,8 +2539,8 @@ class FormHelperTest < ActionView::TestCase
       }
     end
 
-    expected = whole_form('/posts/123', 'edit_post_123', 'edit_post', method: 'patch') do
-      '<input name="post[title]" type="text" id="post_title" value="Hello World" />' +
+    expected = whole_form("/posts/123", "edit_post_123", "edit_post", method: "patch") do
+      '<input name="post[title]" type="text" id="post_title" value="Hello World" />' \
       '<input id="post_author_attributes_name" name="post[author_attributes][name]" type="text" value="author #321" />'
     end
 
@@ -2576,9 +2557,9 @@ class FormHelperTest < ActionView::TestCase
       }
     end
 
-    expected = whole_form('/posts/123', 'edit_post_123', 'edit_post', method: 'patch') do
-      '<input name="post[title]" type="text" id="post_title" value="Hello World" />' +
-      '<input id="post_author_attributes_name" name="post[author_attributes][name]" type="text" value="author #321" />' +
+    expected = whole_form("/posts/123", "edit_post_123", "edit_post", method: "patch") do
+      '<input name="post[title]" type="text" id="post_title" value="Hello World" />' \
+      '<input id="post_author_attributes_name" name="post[author_attributes][name]" type="text" value="author #321" />' \
       '<input id="post_author_attributes_id" name="post[author_attributes][id]" type="hidden" value="321" />'
     end
 
@@ -2596,9 +2577,9 @@ class FormHelperTest < ActionView::TestCase
       }
     end
 
-    expected = whole_form('/posts/123', 'edit_post_123', 'edit_post', method: 'patch') do
-      '<input name="post[title]" type="text" id="post_title" value="Hello World" />' +
-      '<input id="post_author_attributes_id" name="post[author_attributes][id]" type="hidden" value="321" />' +
+    expected = whole_form("/posts/123", "edit_post_123", "edit_post", method: "patch") do
+      '<input name="post[title]" type="text" id="post_title" value="Hello World" />' \
+      '<input id="post_author_attributes_id" name="post[author_attributes][id]" type="hidden" value="321" />' \
       '<input id="post_author_attributes_name" name="post[author_attributes][name]" type="text" value="author #321" />'
     end
 
@@ -2617,11 +2598,11 @@ class FormHelperTest < ActionView::TestCase
       end
     end
 
-    expected = whole_form('/posts/123', 'edit_post_123', 'edit_post', method: 'patch') do
-      '<input name="post[title]" type="text" id="post_title" value="Hello World" />' +
-      '<input id="post_comments_attributes_0_name" name="post[comments_attributes][0][name]" type="text" value="comment #1" />' +
-      '<input id="post_comments_attributes_0_id" name="post[comments_attributes][0][id]" type="hidden" value="1" />' +
-      '<input id="post_comments_attributes_1_name" name="post[comments_attributes][1][name]" type="text" value="comment #2" />' +
+    expected = whole_form("/posts/123", "edit_post_123", "edit_post", method: "patch") do
+      '<input name="post[title]" type="text" id="post_title" value="Hello World" />' \
+      '<input id="post_comments_attributes_0_name" name="post[comments_attributes][0][name]" type="text" value="comment #1" />' \
+      '<input id="post_comments_attributes_0_id" name="post[comments_attributes][0][id]" type="hidden" value="1" />' \
+      '<input id="post_comments_attributes_1_name" name="post[comments_attributes][1][name]" type="text" value="comment #2" />' \
       '<input id="post_comments_attributes_1_id" name="post[comments_attributes][1][id]" type="hidden" value="2" />'
     end
 
@@ -2644,11 +2625,11 @@ class FormHelperTest < ActionView::TestCase
       end
     end
 
-    expected = whole_form('/posts/123', 'edit_post_123', 'edit_post', method: 'patch') do
-      '<input name="post[title]" type="text" id="post_title" value="Hello World" />' +
-      '<input id="post_author_attributes_name" name="post[author_attributes][name]" type="text" value="author #321" />' +
-      '<input id="post_author_attributes_id" name="post[author_attributes][id]" type="hidden" value="321" />' +
-      '<input id="post_comments_attributes_0_name" name="post[comments_attributes][0][name]" type="text" value="comment #1" />' +
+    expected = whole_form("/posts/123", "edit_post_123", "edit_post", method: "patch") do
+      '<input name="post[title]" type="text" id="post_title" value="Hello World" />' \
+      '<input id="post_author_attributes_name" name="post[author_attributes][name]" type="text" value="author #321" />' \
+      '<input id="post_author_attributes_id" name="post[author_attributes][id]" type="hidden" value="321" />' \
+      '<input id="post_comments_attributes_0_name" name="post[comments_attributes][0][name]" type="text" value="comment #1" />' \
       '<input id="post_comments_attributes_1_name" name="post[comments_attributes][1][name]" type="text" value="comment #2" />'
     end
 
@@ -2671,10 +2652,10 @@ class FormHelperTest < ActionView::TestCase
       end
     end
 
-    expected = whole_form('/posts/123', 'edit_post_123', 'edit_post', method: 'patch') do
-      '<input name="post[title]" type="text" id="post_title" value="Hello World" />' +
-      '<input id="post_author_attributes_name" name="post[author_attributes][name]" type="text" value="author #321" />' +
-      '<input id="post_comments_attributes_0_name" name="post[comments_attributes][0][name]" type="text" value="comment #1" />' +
+    expected = whole_form("/posts/123", "edit_post_123", "edit_post", method: "patch") do
+      '<input name="post[title]" type="text" id="post_title" value="Hello World" />' \
+      '<input id="post_author_attributes_name" name="post[author_attributes][name]" type="text" value="author #321" />' \
+      '<input id="post_comments_attributes_0_name" name="post[comments_attributes][0][name]" type="text" value="comment #1" />' \
       '<input id="post_comments_attributes_1_name" name="post[comments_attributes][1][name]" type="text" value="comment #2" />'
     end
 
@@ -2697,11 +2678,11 @@ class FormHelperTest < ActionView::TestCase
       end
     end
 
-    expected = whole_form('/posts/123', 'edit_post_123', 'edit_post', method: 'patch') do
-      '<input name="post[title]" type="text" id="post_title" value="Hello World" />' +
-      '<input id="post_author_attributes_name" name="post[author_attributes][name]" type="text" value="author #321" />' +
-      '<input id="post_author_attributes_id" name="post[author_attributes][id]" type="hidden" value="321" />' +
-      '<input id="post_comments_attributes_0_name" name="post[comments_attributes][0][name]" type="text" value="comment #1" />' +
+    expected = whole_form("/posts/123", "edit_post_123", "edit_post", method: "patch") do
+      '<input name="post[title]" type="text" id="post_title" value="Hello World" />' \
+      '<input id="post_author_attributes_name" name="post[author_attributes][name]" type="text" value="author #321" />' \
+      '<input id="post_author_attributes_id" name="post[author_attributes][id]" type="hidden" value="321" />' \
+      '<input id="post_comments_attributes_0_name" name="post[comments_attributes][0][name]" type="text" value="comment #1" />' \
       '<input id="post_comments_attributes_1_name" name="post[comments_attributes][1][name]" type="text" value="comment #2" />'
     end
 
@@ -2720,11 +2701,11 @@ class FormHelperTest < ActionView::TestCase
       end
     end
 
-    expected = whole_form('/posts/123', 'edit_post_123', 'edit_post', method: 'patch') do
-      '<input name="post[title]" type="text" id="post_title" value="Hello World" />' +
-      '<input id="post_comments_attributes_0_name" name="post[comments_attributes][0][name]" type="text" value="comment #1" />' +
-      '<input id="post_comments_attributes_0_id" name="post[comments_attributes][0][id]" type="hidden" value="1" />' +
-      '<input id="post_comments_attributes_1_name" name="post[comments_attributes][1][name]" type="text" value="comment #2" />' +
+    expected = whole_form("/posts/123", "edit_post_123", "edit_post", method: "patch") do
+      '<input name="post[title]" type="text" id="post_title" value="Hello World" />' \
+      '<input id="post_comments_attributes_0_name" name="post[comments_attributes][0][name]" type="text" value="comment #1" />' \
+      '<input id="post_comments_attributes_0_id" name="post[comments_attributes][0][id]" type="hidden" value="1" />' \
+      '<input id="post_comments_attributes_1_name" name="post[comments_attributes][1][name]" type="text" value="comment #2" />' \
       '<input id="post_comments_attributes_1_id" name="post[comments_attributes][1][id]" type="hidden" value="2" />'
     end
 
@@ -2744,11 +2725,11 @@ class FormHelperTest < ActionView::TestCase
       end
     end
 
-    expected = whole_form('/posts/123', 'edit_post_123', 'edit_post', method: 'patch') do
-      '<input name="post[title]" type="text" id="post_title" value="Hello World" />' +
-      '<input id="post_comments_attributes_0_id" name="post[comments_attributes][0][id]" type="hidden" value="1" />' +
-      '<input id="post_comments_attributes_0_name" name="post[comments_attributes][0][name]" type="text" value="comment #1" />' +
-      '<input id="post_comments_attributes_1_id" name="post[comments_attributes][1][id]" type="hidden" value="2" />' +
+    expected = whole_form("/posts/123", "edit_post_123", "edit_post", method: "patch") do
+      '<input name="post[title]" type="text" id="post_title" value="Hello World" />' \
+      '<input id="post_comments_attributes_0_id" name="post[comments_attributes][0][id]" type="hidden" value="1" />' \
+      '<input id="post_comments_attributes_0_name" name="post[comments_attributes][0][name]" type="text" value="comment #1" />' \
+      '<input id="post_comments_attributes_1_id" name="post[comments_attributes][1][id]" type="hidden" value="2" />' \
       '<input id="post_comments_attributes_1_name" name="post[comments_attributes][1][name]" type="text" value="comment #2" />'
     end
 
@@ -2767,9 +2748,9 @@ class FormHelperTest < ActionView::TestCase
       end
     end
 
-    expected = whole_form('/posts/123', 'edit_post_123', 'edit_post', method: 'patch') do
-      '<input name="post[title]" type="text" id="post_title" value="Hello World" />' +
-      '<input id="post_comments_attributes_0_name" name="post[comments_attributes][0][name]" type="text" value="new comment" />' +
+    expected = whole_form("/posts/123", "edit_post_123", "edit_post", method: "patch") do
+      '<input name="post[title]" type="text" id="post_title" value="Hello World" />' \
+      '<input id="post_comments_attributes_0_name" name="post[comments_attributes][0][name]" type="text" value="new comment" />' \
       '<input id="post_comments_attributes_1_name" name="post[comments_attributes][1][name]" type="text" value="new comment" />'
     end
 
@@ -2788,10 +2769,10 @@ class FormHelperTest < ActionView::TestCase
       end
     end
 
-    expected = whole_form('/posts/123', 'edit_post_123', 'edit_post', method: 'patch') do
-      '<input name="post[title]" type="text" id="post_title" value="Hello World" />' +
-      '<input id="post_comments_attributes_0_name" name="post[comments_attributes][0][name]" type="text" value="comment #321" />' +
-      '<input id="post_comments_attributes_0_id" name="post[comments_attributes][0][id]" type="hidden" value="321" />' +
+    expected = whole_form("/posts/123", "edit_post_123", "edit_post", method: "patch") do
+      '<input name="post[title]" type="text" id="post_title" value="Hello World" />' \
+      '<input id="post_comments_attributes_0_name" name="post[comments_attributes][0][name]" type="text" value="comment #321" />' \
+      '<input id="post_comments_attributes_0_id" name="post[comments_attributes][0][id]" type="hidden" value="321" />' \
       '<input id="post_comments_attributes_1_name" name="post[comments_attributes][1][name]" type="text" value="new comment" />'
     end
 
@@ -2806,7 +2787,7 @@ class FormHelperTest < ActionView::TestCase
       end
     end
 
-    expected = whole_form('/posts/123', 'edit_post_123', 'edit_post', method: 'patch') do
+    expected = whole_form("/posts/123", "edit_post_123", "edit_post", method: "patch") do
       '<input name="post[title]" type="text" id="post_title" value="Hello World" />'
     end
 
@@ -2823,11 +2804,11 @@ class FormHelperTest < ActionView::TestCase
       }
     end
 
-    expected = whole_form('/posts/123', 'edit_post_123', 'edit_post', method: 'patch') do
-      '<input name="post[title]" type="text" id="post_title" value="Hello World" />' +
-      '<input id="post_comments_attributes_0_name" name="post[comments_attributes][0][name]" type="text" value="comment #1" />' +
-      '<input id="post_comments_attributes_0_id" name="post[comments_attributes][0][id]" type="hidden" value="1" />' +
-      '<input id="post_comments_attributes_1_name" name="post[comments_attributes][1][name]" type="text" value="comment #2" />' +
+    expected = whole_form("/posts/123", "edit_post_123", "edit_post", method: "patch") do
+      '<input name="post[title]" type="text" id="post_title" value="Hello World" />' \
+      '<input id="post_comments_attributes_0_name" name="post[comments_attributes][0][name]" type="text" value="comment #1" />' \
+      '<input id="post_comments_attributes_0_id" name="post[comments_attributes][0][id]" type="hidden" value="1" />' \
+      '<input id="post_comments_attributes_1_name" name="post[comments_attributes][1][name]" type="text" value="comment #2" />' \
       '<input id="post_comments_attributes_1_id" name="post[comments_attributes][1][id]" type="hidden" value="2" />'
     end
 
@@ -2844,11 +2825,11 @@ class FormHelperTest < ActionView::TestCase
       }
     end
 
-    expected = whole_form('/posts/123', 'edit_post_123', 'edit_post', method: 'patch') do
-      '<input name="post[title]" type="text" id="post_title" value="Hello World" />' +
-      '<input id="post_comments_attributes_0_name" name="post[comments_attributes][0][name]" type="text" value="comment #1" />' +
-      '<input id="post_comments_attributes_0_id" name="post[comments_attributes][0][id]" type="hidden" value="1" />' +
-      '<input id="post_comments_attributes_1_name" name="post[comments_attributes][1][name]" type="text" value="comment #2" />' +
+    expected = whole_form("/posts/123", "edit_post_123", "edit_post", method: "patch") do
+      '<input name="post[title]" type="text" id="post_title" value="Hello World" />' \
+      '<input id="post_comments_attributes_0_name" name="post[comments_attributes][0][name]" type="text" value="comment #1" />' \
+      '<input id="post_comments_attributes_0_id" name="post[comments_attributes][0][id]" type="hidden" value="1" />' \
+      '<input id="post_comments_attributes_1_name" name="post[comments_attributes][1][name]" type="text" value="comment #2" />' \
       '<input id="post_comments_attributes_1_id" name="post[comments_attributes][1][id]" type="hidden" value="2" />'
     end
 
@@ -2858,7 +2839,7 @@ class FormHelperTest < ActionView::TestCase
   def test_nested_fields_label_translation_with_more_than_10_records
     @post.comments = Array.new(11) { |id| Comment.new(id + 1) }
 
-    params = 11.times.map { ['post.comments.body', default: [:"comment.body", ''], scope: "helpers.label"] }
+    params = 11.times.map { ["post.comments.body", default: [:"comment.body", ""], scope: "helpers.label"] }
     assert_called_with(I18n, :t, params, returns: "Write body here") do
       form_for(@post) do |f|
         f.fields_for(:comments) do |cf|
@@ -2879,11 +2860,11 @@ class FormHelperTest < ActionView::TestCase
       }
     end
 
-    expected = whole_form('/posts/123', 'edit_post_123', 'edit_post', method: 'patch') do
-      '<input name="post[title]" type="text" id="post_title" value="Hello World" />' +
-      '<input id="post_comments_attributes_0_name" name="post[comments_attributes][0][name]" type="text" value="comment #1" />' +
-      '<input id="post_comments_attributes_0_id" name="post[comments_attributes][0][id]" type="hidden" value="1" />' +
-      '<input id="post_comments_attributes_1_name" name="post[comments_attributes][1][name]" type="text" value="comment #2" />' +
+    expected = whole_form("/posts/123", "edit_post_123", "edit_post", method: "patch") do
+      '<input name="post[title]" type="text" id="post_title" value="Hello World" />' \
+      '<input id="post_comments_attributes_0_name" name="post[comments_attributes][0][name]" type="text" value="comment #1" />' \
+      '<input id="post_comments_attributes_0_id" name="post[comments_attributes][0][id]" type="hidden" value="1" />' \
+      '<input id="post_comments_attributes_1_name" name="post[comments_attributes][1][name]" type="text" value="comment #2" />' \
       '<input id="post_comments_attributes_1_id" name="post[comments_attributes][1][id]" type="hidden" value="2" />'
     end
 
@@ -2902,10 +2883,10 @@ class FormHelperTest < ActionView::TestCase
       }
     end
 
-    expected = whole_form('/posts/123', 'edit_post_123', 'edit_post', method: 'patch') do
-      '<input name="post[title]" type="text" id="post_title" value="Hello World" />' +
-      '<input id="post_comments_attributes_0_name" name="post[comments_attributes][0][name]" type="text" value="comment #321" />' +
-      '<input id="post_comments_attributes_0_id" name="post[comments_attributes][0][id]" type="hidden" value="321" />' +
+    expected = whole_form("/posts/123", "edit_post_123", "edit_post", method: "patch") do
+      '<input name="post[title]" type="text" id="post_title" value="Hello World" />' \
+      '<input id="post_comments_attributes_0_name" name="post[comments_attributes][0][name]" type="text" value="comment #321" />' \
+      '<input id="post_comments_attributes_0_id" name="post[comments_attributes][0][id]" type="hidden" value="321" />' \
       '<input id="post_comments_attributes_1_name" name="post[comments_attributes][1][name]" type="text" value="new comment" />'
     end
 
@@ -2917,13 +2898,13 @@ class FormHelperTest < ActionView::TestCase
     @post.comments = []
 
     form_for(@post) do |f|
-      concat f.fields_for(:comments, Comment.new(321), child_index: 'abc') { |cf|
+      concat f.fields_for(:comments, Comment.new(321), child_index: "abc") { |cf|
         concat cf.text_field(:name)
       }
     end
 
-    expected = whole_form('/posts/123', 'edit_post_123', 'edit_post', method: 'patch') do
-      '<input id="post_comments_attributes_abc_name" name="post[comments_attributes][abc][name]" type="text" value="comment #321" />' +
+    expected = whole_form("/posts/123", "edit_post_123", "edit_post", method: "patch") do
+      '<input id="post_comments_attributes_abc_name" name="post[comments_attributes][abc][name]" type="text" value="comment #321" />' \
       '<input id="post_comments_attributes_abc_id" name="post[comments_attributes][abc][id]" type="hidden" value="321" />'
     end
 
@@ -2934,13 +2915,13 @@ class FormHelperTest < ActionView::TestCase
     @post.comments = []
 
     form_for(@post) do |f|
-      concat f.fields_for(:comments, Comment.new(321), child_index: -> { 'abc' } ) { |cf|
+      concat f.fields_for(:comments, Comment.new(321), child_index: -> { "abc" }) { |cf|
         concat cf.text_field(:name)
       }
     end
 
-    expected = whole_form('/posts/123', 'edit_post_123', 'edit_post', method: 'patch') do
-      '<input id="post_comments_attributes_abc_name" name="post[comments_attributes][abc][name]" type="text" value="comment #321" />' +
+    expected = whole_form("/posts/123", "edit_post_123", "edit_post", method: "patch") do
+      '<input id="post_comments_attributes_abc_name" name="post[comments_attributes][abc][name]" type="text" value="comment #321" />' \
       '<input id="post_comments_attributes_abc_id" name="post[comments_attributes][abc][id]" type="hidden" value="321" />'
     end
 
@@ -2957,13 +2938,13 @@ class FormHelperTest < ActionView::TestCase
     @post.comments = FakeAssociationProxy.new
 
     form_for(@post) do |f|
-      concat f.fields_for(:comments, Comment.new(321), child_index: 'abc') { |cf|
+      concat f.fields_for(:comments, Comment.new(321), child_index: "abc") { |cf|
         concat cf.text_field(:name)
       }
     end
 
-    expected = whole_form('/posts/123', 'edit_post_123', 'edit_post', method: 'patch') do
-      '<input id="post_comments_attributes_abc_name" name="post[comments_attributes][abc][name]" type="text" value="comment #321" />' +
+    expected = whole_form("/posts/123", "edit_post_123", "edit_post", method: "patch") do
+      '<input id="post_comments_attributes_abc_name" name="post[comments_attributes][abc][name]" type="text" value="comment #321" />' \
       '<input id="post_comments_attributes_abc_id" name="post[comments_attributes][abc][id]" type="hidden" value="321" />'
     end
 
@@ -2977,7 +2958,7 @@ class FormHelperTest < ActionView::TestCase
       expected = 0
       @post.comments.each do |comment|
         f.fields_for(:comments, comment) { |cf|
-          assert_equal cf.index, expected
+          assert_equal expected, cf.index
           expected += 1
         }
       end
@@ -2991,7 +2972,7 @@ class FormHelperTest < ActionView::TestCase
       expected = 0
       @post.comments.each do |comment|
         f.fields_for(:comments, comment) { |cf|
-          assert_equal cf.index, expected
+          assert_equal expected, cf.index
           expected += 1
         }
       end
@@ -3004,7 +2985,7 @@ class FormHelperTest < ActionView::TestCase
     form_for(@post) do |f|
       expected = 0
       f.fields_for(:comments, @post.comments) { |cf|
-        assert_equal cf.index, expected
+        assert_equal expected, cf.index
         expected += 1
       }
     end
@@ -3014,8 +2995,8 @@ class FormHelperTest < ActionView::TestCase
     @post.comments = []
 
     form_for(@post) do |f|
-      f.fields_for(:comments, Comment.new(321), child_index: 'abc') { |cf|
-        assert_equal cf.index, 'abc'
+      f.fields_for(:comments, Comment.new(321), child_index: "abc") { |cf|
+        assert_equal "abc", cf.index
       }
     end
   end
@@ -3040,7 +3021,7 @@ class FormHelperTest < ActionView::TestCase
           concat trf.text_field(:value)
         }
       }
-      concat f.fields_for('tags', @post.tags[1]) { |tf|
+      concat f.fields_for("tags", @post.tags[1]) { |tf|
         concat tf.text_field(:value)
         concat tf.fields_for(:relevances, TagRelevance.new(31415)) { |trf|
           concat trf.text_field(:value)
@@ -3048,18 +3029,18 @@ class FormHelperTest < ActionView::TestCase
       }
     end
 
-    expected = whole_form('/posts/123', 'edit_post_123', 'edit_post', method: 'patch') do
-      '<input id="post_comments_attributes_0_name" name="post[comments_attributes][0][name]" type="text" value="comment #321" />' +
-      '<input id="post_comments_attributes_0_relevances_attributes_0_value" name="post[comments_attributes][0][relevances_attributes][0][value]" type="text" value="commentrelevance #314" />' +
-      '<input id="post_comments_attributes_0_relevances_attributes_0_id" name="post[comments_attributes][0][relevances_attributes][0][id]" type="hidden" value="314" />' +
-      '<input id="post_comments_attributes_0_id" name="post[comments_attributes][0][id]" type="hidden" value="321" />' +
-      '<input id="post_tags_attributes_0_value" name="post[tags_attributes][0][value]" type="text" value="tag #123" />' +
-      '<input id="post_tags_attributes_0_relevances_attributes_0_value" name="post[tags_attributes][0][relevances_attributes][0][value]" type="text" value="tagrelevance #3141" />' +
-      '<input id="post_tags_attributes_0_relevances_attributes_0_id" name="post[tags_attributes][0][relevances_attributes][0][id]" type="hidden" value="3141" />' +
-      '<input id="post_tags_attributes_0_id" name="post[tags_attributes][0][id]" type="hidden" value="123" />' +
-      '<input id="post_tags_attributes_1_value" name="post[tags_attributes][1][value]" type="text" value="tag #456" />' +
-      '<input id="post_tags_attributes_1_relevances_attributes_0_value" name="post[tags_attributes][1][relevances_attributes][0][value]" type="text" value="tagrelevance #31415" />' +
-      '<input id="post_tags_attributes_1_relevances_attributes_0_id" name="post[tags_attributes][1][relevances_attributes][0][id]" type="hidden" value="31415" />' +
+    expected = whole_form("/posts/123", "edit_post_123", "edit_post", method: "patch") do
+      '<input id="post_comments_attributes_0_name" name="post[comments_attributes][0][name]" type="text" value="comment #321" />' \
+      '<input id="post_comments_attributes_0_relevances_attributes_0_value" name="post[comments_attributes][0][relevances_attributes][0][value]" type="text" value="commentrelevance #314" />' \
+      '<input id="post_comments_attributes_0_relevances_attributes_0_id" name="post[comments_attributes][0][relevances_attributes][0][id]" type="hidden" value="314" />' \
+      '<input id="post_comments_attributes_0_id" name="post[comments_attributes][0][id]" type="hidden" value="321" />' \
+      '<input id="post_tags_attributes_0_value" name="post[tags_attributes][0][value]" type="text" value="tag #123" />' \
+      '<input id="post_tags_attributes_0_relevances_attributes_0_value" name="post[tags_attributes][0][relevances_attributes][0][value]" type="text" value="tagrelevance #3141" />' \
+      '<input id="post_tags_attributes_0_relevances_attributes_0_id" name="post[tags_attributes][0][relevances_attributes][0][id]" type="hidden" value="3141" />' \
+      '<input id="post_tags_attributes_0_id" name="post[tags_attributes][0][id]" type="hidden" value="123" />' \
+      '<input id="post_tags_attributes_1_value" name="post[tags_attributes][1][value]" type="text" value="tag #456" />' \
+      '<input id="post_tags_attributes_1_relevances_attributes_0_value" name="post[tags_attributes][1][relevances_attributes][0][value]" type="text" value="tagrelevance #31415" />' \
+      '<input id="post_tags_attributes_1_relevances_attributes_0_id" name="post[tags_attributes][1][relevances_attributes][0][id]" type="hidden" value="31415" />' \
       '<input id="post_tags_attributes_1_id" name="post[tags_attributes][1][id]" type="hidden" value="456" />'
     end
 
@@ -3075,7 +3056,7 @@ class FormHelperTest < ActionView::TestCase
       }
     end
 
-    expected = whole_form('/posts/123', 'edit_post_123', 'edit_post', method: 'patch') do
+    expected = whole_form("/posts/123", "edit_post_123", "edit_post", method: "patch") do
       '<input id="post_author_attributes_name" name="post[author_attributes][name]" type="text" value="hash backed author" />'
     end
 
@@ -3090,9 +3071,9 @@ class FormHelperTest < ActionView::TestCase
     end
 
     expected =
-      "<input name='post[title]' type='text' id='post_title' value='Hello World' />" +
-      "<textarea name='post[body]' id='post_body'>\nBack to the hill and over it again!</textarea>" +
-      "<input name='post[secret]' type='hidden' value='0' />" +
+      "<input name='post[title]' type='text' id='post_title' value='Hello World' />" \
+      "<textarea name='post[body]' id='post_body'>\nBack to the hill and over it again!</textarea>" \
+      "<input name='post[secret]' type='hidden' value='0' />" \
       "<input name='post[secret]' checked='checked' type='checkbox' id='post_secret' value='1' />"
 
     assert_dom_equal expected, output_buffer
@@ -3106,9 +3087,9 @@ class FormHelperTest < ActionView::TestCase
     end
 
     expected =
-      "<input name='post[123][title]' type='text' id='post_123_title' value='Hello World' />" +
-      "<textarea name='post[123][body]' id='post_123_body'>\nBack to the hill and over it again!</textarea>" +
-      "<input name='post[123][secret]' type='hidden' value='0' />" +
+      "<input name='post[123][title]' type='text' id='post_123_title' value='Hello World' />" \
+      "<textarea name='post[123][body]' id='post_123_body'>\nBack to the hill and over it again!</textarea>" \
+      "<input name='post[123][secret]' type='hidden' value='0' />" \
       "<input name='post[123][secret]' checked='checked' type='checkbox' id='post_123_secret' value='1' />"
 
     assert_dom_equal expected, output_buffer
@@ -3122,9 +3103,9 @@ class FormHelperTest < ActionView::TestCase
     end
 
     expected =
-      "<input name='post[][title]' type='text' id='post__title' value='Hello World' />" +
-      "<textarea name='post[][body]' id='post__body'>\nBack to the hill and over it again!</textarea>" +
-      "<input name='post[][secret]' type='hidden' value='0' />" +
+      "<input name='post[][title]' type='text' id='post__title' value='Hello World' />" \
+      "<textarea name='post[][body]' id='post__body'>\nBack to the hill and over it again!</textarea>" \
+      "<input name='post[][secret]' type='hidden' value='0' />" \
       "<input name='post[][secret]' checked='checked' type='checkbox' id='post__secret' value='1' />"
 
     assert_dom_equal expected, output_buffer
@@ -3138,9 +3119,9 @@ class FormHelperTest < ActionView::TestCase
     end
 
     expected =
-      "<input name='post[abc][title]' type='text' id='post_abc_title' value='Hello World' />" +
-      "<textarea name='post[abc][body]' id='post_abc_body'>\nBack to the hill and over it again!</textarea>" +
-      "<input name='post[abc][secret]' type='hidden' value='0' />" +
+      "<input name='post[abc][title]' type='text' id='post_abc_title' value='Hello World' />" \
+      "<textarea name='post[abc][body]' id='post_abc_body'>\nBack to the hill and over it again!</textarea>" \
+      "<input name='post[abc][secret]' type='hidden' value='0' />" \
       "<input name='post[abc][secret]' checked='checked' type='checkbox' id='post_abc_secret' value='1' />"
 
     assert_dom_equal expected, output_buffer
@@ -3154,9 +3135,9 @@ class FormHelperTest < ActionView::TestCase
     end
 
     expected =
-      "<input name='post[title]' type='text' id='post_title' value='Hello World' />" +
-      "<textarea name='post[body]' id='post_body'>\nBack to the hill and over it again!</textarea>" +
-      "<input name='post[secret]' type='hidden' value='0' />" +
+      "<input name='post[title]' type='text' id='post_title' value='Hello World' />" \
+      "<textarea name='post[body]' id='post_body'>\nBack to the hill and over it again!</textarea>" \
+      "<input name='post[secret]' type='hidden' value='0' />" \
       "<input name='post[secret]' checked='checked' type='checkbox' id='post_secret' value='1' />"
 
     assert_dom_equal expected, output_buffer
@@ -3170,9 +3151,9 @@ class FormHelperTest < ActionView::TestCase
     end
 
     expected =
-      "<input name='post[title]' type='text' id='post_title' value='Hello World' />" +
-      "<textarea name='post[body]' id='post_body'>\nBack to the hill and over it again!</textarea>" +
-      "<input name='post[secret]' type='hidden' value='0' />" +
+      "<input name='post[title]' type='text' id='post_title' value='Hello World' />" \
+      "<textarea name='post[body]' id='post_body'>\nBack to the hill and over it again!</textarea>" \
+      "<input name='post[secret]' type='hidden' value='0' />" \
       "<input name='post[secret]' checked='checked' type='checkbox' id='post_secret' value='1' />"
 
     assert_dom_equal expected, output_buffer
@@ -3184,7 +3165,7 @@ class FormHelperTest < ActionView::TestCase
       concat f.text_field(:title)
     end
 
-    assert_dom_equal "<label for=\"author_post_title\">Title</label>" +
+    assert_dom_equal "<label for=\"author_post_title\">Title</label>" \
     "<input name='author[post][title]' type='text' id='author_post_title' value='Hello World' />",
       output_buffer
   end
@@ -3195,17 +3176,17 @@ class FormHelperTest < ActionView::TestCase
       concat f.text_field(:title)
     end
 
-    assert_dom_equal "<label for=\"author_post_1_title\">Title</label>" +
+    assert_dom_equal "<label for=\"author_post_1_title\">Title</label>" \
       "<input name='author[post][1][title]' type='text' id='author_post_1_title' value='Hello World' />",
       output_buffer
   end
 
   def test_form_builder_does_not_have_form_for_method
-    assert !ActionView::Helpers::FormBuilder.instance_methods.include?(:form_for)
+    assert_not_includes ActionView::Helpers::FormBuilder.instance_methods, :form_for
   end
 
   def test_form_for_and_fields_for
-    form_for(@post, as: :post, html: { id: 'create-post' }) do |post_form|
+    form_for(@post, as: :post, html: { id: "create-post" }) do |post_form|
       concat post_form.text_field(:title)
       concat post_form.text_area(:body)
 
@@ -3214,10 +3195,10 @@ class FormHelperTest < ActionView::TestCase
       }
     end
 
-    expected = whole_form('/posts/123', 'create-post', 'edit_post', method: 'patch') do
-      "<input name='post[title]' type='text' id='post_title' value='Hello World' />" +
-      "<textarea name='post[body]' id='post_body'>\nBack to the hill and over it again!</textarea>" +
-      "<input name='parent_post[secret]' type='hidden' value='0' />" +
+    expected = whole_form("/posts/123", "create-post", "edit_post", method: "patch") do
+      "<input name='post[title]' type='text' id='post_title' value='Hello World' />" \
+      "<textarea name='post[body]' id='post_body'>\nBack to the hill and over it again!</textarea>" \
+      "<input name='parent_post[secret]' type='hidden' value='0' />" \
       "<input name='parent_post[secret]' checked='checked' type='checkbox' id='parent_post_secret' value='1' />"
     end
 
@@ -3225,7 +3206,7 @@ class FormHelperTest < ActionView::TestCase
   end
 
   def test_form_for_and_fields_for_with_object
-    form_for(@post, as: :post, html: { id: 'create-post' }) do |post_form|
+    form_for(@post, as: :post, html: { id: "create-post" }) do |post_form|
       concat post_form.text_field(:title)
       concat post_form.text_area(:body)
 
@@ -3234,9 +3215,9 @@ class FormHelperTest < ActionView::TestCase
       }
     end
 
-    expected = whole_form('/posts/123', 'create-post', 'edit_post', method: 'patch') do
-      "<input name='post[title]' type='text' id='post_title' value='Hello World' />" +
-      "<textarea name='post[body]' id='post_body'>\nBack to the hill and over it again!</textarea>" +
+    expected = whole_form("/posts/123", "create-post", "edit_post", method: "patch") do
+      "<input name='post[title]' type='text' id='post_title' value='Hello World' />" \
+      "<textarea name='post[body]' id='post_body'>\nBack to the hill and over it again!</textarea>" \
       "<input name='post[comment][name]' type='text' id='post_comment_name' value='new comment' />"
     end
 
@@ -3250,7 +3231,7 @@ class FormHelperTest < ActionView::TestCase
       }
     end
 
-    expected = whole_form('/posts/123', 'edit_post_123', 'edit_post', method: 'patch') do
+    expected = whole_form("/posts/123", "edit_post_123", "edit_post", method: "patch") do
       "<input name='post[category][name]' type='text' id='post_category_name' />"
     end
 
@@ -3274,9 +3255,9 @@ class FormHelperTest < ActionView::TestCase
       concat f.check_box(:secret)
     end
 
-    expected = whole_form('/posts/123', 'edit_post_123', 'edit_post', method: 'patch') do
-      "<label for='title'>Title:</label> <input name='post[title]' type='text' id='post_title' value='Hello World' /><br/>" +
-      "<label for='body'>Body:</label> <textarea name='post[body]' id='post_body'>\nBack to the hill and over it again!</textarea><br/>" +
+    expected = whole_form("/posts/123", "edit_post_123", "edit_post", method: "patch") do
+      "<label for='title'>Title:</label> <input name='post[title]' type='text' id='post_title' value='Hello World' /><br/>" \
+      "<label for='body'>Body:</label> <textarea name='post[body]' id='post_body'>\nBack to the hill and over it again!</textarea><br/>" \
       "<label for='secret'>Secret:</label> <input name='post[secret]' type='hidden' value='0' /><input name='post[secret]' checked='checked' type='checkbox' id='post_secret' value='1' /><br/>"
     end
 
@@ -3293,9 +3274,9 @@ class FormHelperTest < ActionView::TestCase
       concat f.check_box(:secret)
     end
 
-    expected = whole_form('/posts/123', 'edit_post_123', 'edit_post', method: 'patch') do
-      "<label for='title'>Title:</label> <input name='post[title]' type='text' id='post_title' value='Hello World' /><br/>" +
-      "<label for='body'>Body:</label> <textarea name='post[body]' id='post_body'>\nBack to the hill and over it again!</textarea><br/>" +
+    expected = whole_form("/posts/123", "edit_post_123", "edit_post", method: "patch") do
+      "<label for='title'>Title:</label> <input name='post[title]' type='text' id='post_title' value='Hello World' /><br/>" \
+      "<label for='body'>Body:</label> <textarea name='post[body]' id='post_body'>\nBack to the hill and over it again!</textarea><br/>" \
       "<label for='secret'>Secret:</label> <input name='post[secret]' type='hidden' value='0' /><input name='post[secret]' checked='checked' type='checkbox' id='post_secret' value='1' /><br/>"
     end
 
@@ -3312,7 +3293,7 @@ class FormHelperTest < ActionView::TestCase
       concat f.text_field(:title)
     end
 
-    expected = whole_form('/posts/123', 'edit_post_123', 'edit_post', method: 'patch') do
+    expected = whole_form("/posts/123", "edit_post_123", "edit_post", method: "patch") do
       "<label for='title'>Title:</label> <input name='post[title]' type='text' id='post_title' value='Hello World' /><br/>"
     end
 
@@ -3353,8 +3334,8 @@ class FormHelperTest < ActionView::TestCase
     end
 
     expected =
-      "<label for='title'>Title:</label> <input name='post[title]' type='text' id='post_title' value='Hello World' /><br/>" +
-      "<label for='body'>Body:</label> <textarea name='post[body]' id='post_body'>\nBack to the hill and over it again!</textarea><br/>" +
+      "<label for='title'>Title:</label> <input name='post[title]' type='text' id='post_title' value='Hello World' /><br/>" \
+      "<label for='body'>Body:</label> <textarea name='post[body]' id='post_body'>\nBack to the hill and over it again!</textarea><br/>" \
       "<label for='secret'>Secret:</label> <input name='post[secret]' type='hidden' value='0' /><input name='post[secret]' checked='checked' type='checkbox' id='post_secret' value='1' /><br/>"
 
     assert_dom_equal expected, output_buffer
@@ -3366,7 +3347,7 @@ class FormHelperTest < ActionView::TestCase
     form_for(@post, builder: LabelledFormBuilder) do |f|
       f.fields_for(:comments, Comment.new) do |nested_fields|
         klass = nested_fields.class
-        ''
+        ""
       end
     end
 
@@ -3377,9 +3358,9 @@ class FormHelperTest < ActionView::TestCase
     klass = nil
 
     form_for(@post, builder: LabelledFormBuilder) do |f|
-      f.fields_for(:comments, Comment.new, index: 'foo') do |nested_fields|
+      f.fields_for(:comments, Comment.new, index: "foo") do |nested_fields|
         klass = nested_fields.class
-        ''
+        ""
       end
     end
 
@@ -3391,10 +3372,10 @@ class FormHelperTest < ActionView::TestCase
 
     form_for(@post, builder: LabelledFormBuilder) do |f|
       path = f.to_partial_path
-      ''
+      ""
     end
 
-    assert_equal 'labelled_form', path
+    assert_equal "labelled_form", path
   end
 
   class LabelledFormBuilderSubclass < LabelledFormBuilder; end
@@ -3405,7 +3386,7 @@ class FormHelperTest < ActionView::TestCase
     form_for(@post, builder: LabelledFormBuilder) do |f|
       f.fields_for(:comments, Comment.new, builder: LabelledFormBuilderSubclass) do |nested_fields|
         klass = nested_fields.class
-        ''
+        ""
       end
     end
 
@@ -3413,23 +3394,23 @@ class FormHelperTest < ActionView::TestCase
   end
 
   def test_form_for_with_html_options_adds_options_to_form_tag
-    form_for(@post, html: { id: 'some_form', class: 'some_class', multipart: true }) do |f| end
+    form_for(@post, html: { id: "some_form", class: "some_class", multipart: true }) do |f| end
     expected = whole_form("/posts/123", "some_form", "some_class", method: "patch", multipart: "multipart/form-data")
 
     assert_dom_equal expected, output_buffer
   end
 
   def test_form_for_with_string_url_option
-    form_for(@post, url: 'http://www.otherdomain.com') do |f| end
+    form_for(@post, url: "http://www.otherdomain.com") do |f| end
 
     assert_dom_equal whole_form("http://www.otherdomain.com", "edit_post_123", "edit_post", method: "patch"), output_buffer
   end
 
   def test_form_for_with_hash_url_option
-    form_for(@post, url: { controller: 'controller', action: 'action' }) do |f| end
+    form_for(@post, url: { controller: "controller", action: "action" }) do |f| end
 
-    assert_equal 'controller', @url_for_options[:controller]
-    assert_equal 'action', @url_for_options[:action]
+    assert_equal "controller", @url_for_options[:controller]
+    assert_equal "action", @url_for_options[:action]
   end
 
   def test_form_for_with_record_url_option
@@ -3520,54 +3501,54 @@ class FormHelperTest < ActionView::TestCase
       end
     end
 
-    form_for(@post, builder: builder_class) { }
-    assert_equal 1, initialization_count, 'form builder instantiated more than once'
+    form_for(@post, builder: builder_class) {}
+    assert_equal 1, initialization_count, "form builder instantiated more than once"
   end
 
-  protected
+  private
 
-  def hidden_fields(options = {})
-    method = options[:method]
+    def hidden_fields(options = {})
+      method = options[:method]
 
-    if options.fetch(:enforce_utf8, true)
-      txt = %{<input name="utf8" type="hidden" value="&#x2713;" />}
-    else
-      txt = ''
-    end
+      if options.fetch(:enforce_utf8, true)
+        txt = %{<input name="utf8" type="hidden" value="&#x2713;" />}.dup
+      else
+        txt = "".dup
+      end
 
-    if method && !%w(get post).include?(method.to_s)
-      txt << %{<input name="_method" type="hidden" value="#{method}" />}
-    end
+      if method && !%w(get post).include?(method.to_s)
+        txt << %{<input name="_method" type="hidden" value="#{method}" />}
+      end
 
-    txt
-  end
+      txt
+    end
 
-  def form_text(action = "/", id = nil, html_class = nil, remote = nil, multipart = nil, method = nil)
-    txt =  %{<form accept-charset="UTF-8" action="#{action}"}
-    txt << %{ enctype="multipart/form-data"} if multipart
-    txt << %{ data-remote="true"} if remote
-    txt << %{ class="#{html_class}"} if html_class
-    txt << %{ id="#{id}"} if id
-    method = method.to_s == "get" ? "get" : "post"
-    txt << %{ method="#{method}">}
-  end
+    def form_text(action = "/", id = nil, html_class = nil, remote = nil, multipart = nil, method = nil)
+      txt =  %{<form accept-charset="UTF-8" action="#{action}"}.dup
+      txt << %{ enctype="multipart/form-data"} if multipart
+      txt << %{ data-remote="true"} if remote
+      txt << %{ class="#{html_class}"} if html_class
+      txt << %{ id="#{id}"} if id
+      method = method.to_s == "get" ? "get" : "post"
+      txt << %{ method="#{method}">}
+    end
 
-  def whole_form(action = "/", id = nil, html_class = nil, options = {})
-    contents = block_given? ? yield : ""
+    def whole_form(action = "/", id = nil, html_class = nil, options = {})
+      contents = block_given? ? yield : ""
 
-    method, remote, multipart = options.values_at(:method, :remote, :multipart)
+      method, remote, multipart = options.values_at(:method, :remote, :multipart)
 
-    form_text(action, id, html_class, remote, multipart, method) + hidden_fields(options.slice :method, :enforce_utf8) + contents + "</form>"
-  end
+      form_text(action, id, html_class, remote, multipart, method) + hidden_fields(options.slice :method, :enforce_utf8) + contents + "</form>"
+    end
 
-  def protect_against_forgery?
-    false
-  end
+    def protect_against_forgery?
+      false
+    end
 
-  def with_locale(testing_locale = :label)
-    old_locale, I18n.locale = I18n.locale, testing_locale
-    yield
-  ensure
-    I18n.locale = old_locale
-  end
+    def with_locale(testing_locale = :label)
+      old_locale, I18n.locale = I18n.locale, testing_locale
+      yield
+    ensure
+      I18n.locale = old_locale
+    end
 end
diff --git a/actionview/test/template/form_options_helper_i18n_test.rb b/actionview/test/template/form_options_helper_i18n_test.rb
index 26ede09a5f..21295fa547 100644
--- a/actionview/test/template/form_options_helper_i18n_test.rb
+++ b/actionview/test/template/form_options_helper_i18n_test.rb
@@ -1,12 +1,14 @@
-require 'abstract_unit'
+# frozen_string_literal: true
+
+require "abstract_unit"
 
 class FormOptionsHelperI18nTests < ActionView::TestCase
   tests ActionView::Helpers::FormOptionsHelper
 
   def setup
-    @prompt_message = 'Select!'
+    @prompt_message = "Select!"
     I18n.backend.send(:init_translations)
-    I18n.backend.store_translations :en, :helpers => { :select => { :prompt => @prompt_message } }
+    I18n.backend.store_translations :en, helpers: { select: { prompt: @prompt_message } }
   end
 
   def teardown
@@ -14,15 +16,15 @@ class FormOptionsHelperI18nTests < ActionView::TestCase
   end
 
   def test_select_with_prompt_true_translates_prompt_message
-    assert_called_with(I18n, :translate, ['helpers.select.prompt', { :default => 'Please select' }]) do
-      select('post', 'category', [], :prompt => true)
+    assert_called_with(I18n, :translate, ["helpers.select.prompt", { default: "Please select" }]) do
+      select("post", "category", [], prompt: true)
     end
   end
 
   def test_select_with_translated_prompt
     assert_dom_equal(
       %Q(<select id="post_category" name="post[category]"><option value="">#{@prompt_message}</option>\n</select>),
-      select('post', 'category', [], :prompt => true)
+      select("post", "category", [], prompt: true)
     )
   end
 end
diff --git a/actionview/test/template/form_options_helper_test.rb b/actionview/test/template/form_options_helper_test.rb
index 7a5904f151..642f450f91 100644
--- a/actionview/test/template/form_options_helper_test.rb
+++ b/actionview/test/template/form_options_helper_test.rb
@@ -1,4 +1,6 @@
-require 'abstract_unit'
+# frozen_string_literal: true
+
+require "abstract_unit"
 
 class Map < Hash
   def category
@@ -6,15 +8,24 @@ class Map < Hash
   end
 end
 
+class CustomEnumerable
+  include Enumerable
+
+  def each
+    yield "one"
+    yield "two"
+  end
+end
+
 class FormOptionsHelperTest < ActionView::TestCase
   tests ActionView::Helpers::FormOptionsHelper
 
   silence_warnings do
-    Post        = Struct.new('Post', :title, :author_name, :body, :secret, :written_on, :category, :origin, :allow_comments)
-    Continent   = Struct.new('Continent', :continent_name, :countries)
-    Country     = Struct.new('Country', :country_id, :country_name)
-    Firm        = Struct.new('Firm', :time_zone)
-    Album       = Struct.new('Album', :id, :title, :genre)
+    Post        = Struct.new("Post", :title, :author_name, :body, :secret, :written_on, :category, :origin, :allow_comments)
+    Continent   = Struct.new("Continent", :continent_name, :countries)
+    Country     = Struct.new("Country", :country_id, :country_name)
+    Firm        = Struct.new("Firm", :time_zone)
+    Album       = Struct.new("Album", :id, :title, :genre)
   end
 
   module FakeZones
@@ -57,7 +68,6 @@ class FormOptionsHelperTest < ActionView::TestCase
     )
   end
 
-
   def test_collection_options_with_preselected_value
     assert_dom_equal(
       "<option value=\"&lt;Abe&gt;\">&lt;Abe&gt; went home</option>\n<option value=\"Babe\" selected=\"selected\">Babe went home</option>\n<option value=\"Cabe\">Cabe went home</option>",
@@ -66,44 +76,44 @@ class FormOptionsHelperTest < ActionView::TestCase
   end
 
   def test_collection_options_with_preselected_value_array
-      assert_dom_equal(
-        "<option value=\"&lt;Abe&gt;\">&lt;Abe&gt; went home</option>\n<option value=\"Babe\" selected=\"selected\">Babe went home</option>\n<option value=\"Cabe\" selected=\"selected\">Cabe went home</option>",
-        options_from_collection_for_select(dummy_posts, "author_name", "title", [ "Babe", "Cabe" ])
-      )
+    assert_dom_equal(
+      "<option value=\"&lt;Abe&gt;\">&lt;Abe&gt; went home</option>\n<option value=\"Babe\" selected=\"selected\">Babe went home</option>\n<option value=\"Cabe\" selected=\"selected\">Cabe went home</option>",
+      options_from_collection_for_select(dummy_posts, "author_name", "title", [ "Babe", "Cabe" ])
+    )
   end
 
   def test_collection_options_with_proc_for_selected
     assert_dom_equal(
       "<option value=\"&lt;Abe&gt;\">&lt;Abe&gt; went home</option>\n<option value=\"Babe\" selected=\"selected\">Babe went home</option>\n<option value=\"Cabe\">Cabe went home</option>",
-      options_from_collection_for_select(dummy_posts, "author_name", "title", lambda{|p| p.author_name == 'Babe' })
+      options_from_collection_for_select(dummy_posts, "author_name", "title", lambda { |p| p.author_name == "Babe" })
     )
   end
 
   def test_collection_options_with_disabled_value
     assert_dom_equal(
       "<option value=\"&lt;Abe&gt;\">&lt;Abe&gt; went home</option>\n<option value=\"Babe\" disabled=\"disabled\">Babe went home</option>\n<option value=\"Cabe\">Cabe went home</option>",
-      options_from_collection_for_select(dummy_posts, "author_name", "title", :disabled => "Babe")
+      options_from_collection_for_select(dummy_posts, "author_name", "title", disabled: "Babe")
     )
   end
 
   def test_collection_options_with_disabled_array
     assert_dom_equal(
       "<option value=\"&lt;Abe&gt;\">&lt;Abe&gt; went home</option>\n<option value=\"Babe\" disabled=\"disabled\">Babe went home</option>\n<option value=\"Cabe\" disabled=\"disabled\">Cabe went home</option>",
-      options_from_collection_for_select(dummy_posts, "author_name", "title", :disabled => [ "Babe", "Cabe" ])
+      options_from_collection_for_select(dummy_posts, "author_name", "title", disabled: [ "Babe", "Cabe" ])
     )
   end
 
   def test_collection_options_with_preselected_and_disabled_value
     assert_dom_equal(
       "<option value=\"&lt;Abe&gt;\">&lt;Abe&gt; went home</option>\n<option value=\"Babe\" disabled=\"disabled\">Babe went home</option>\n<option value=\"Cabe\" selected=\"selected\">Cabe went home</option>",
-      options_from_collection_for_select(dummy_posts, "author_name", "title", :selected => "Cabe", :disabled => "Babe")
+      options_from_collection_for_select(dummy_posts, "author_name", "title", selected: "Cabe", disabled: "Babe")
     )
   end
 
   def test_collection_options_with_proc_for_disabled
     assert_dom_equal(
       "<option value=\"&lt;Abe&gt;\">&lt;Abe&gt; went home</option>\n<option value=\"Babe\" disabled=\"disabled\">Babe went home</option>\n<option value=\"Cabe\" disabled=\"disabled\">Cabe went home</option>",
-      options_from_collection_for_select(dummy_posts, "author_name", "title", :disabled => lambda {|p| %w(Babe Cabe).include?(p.author_name)})
+      options_from_collection_for_select(dummy_posts, "author_name", "title", disabled: lambda { |p| %w(Babe Cabe).include?(p.author_name) })
     )
   end
 
@@ -124,7 +134,7 @@ class FormOptionsHelperTest < ActionView::TestCase
   def test_collection_options_with_element_attributes
     assert_dom_equal(
       "<option value=\"USA\" class=\"bold\">USA</option>",
-      options_from_collection_for_select([[ "USA", "USA", { :class => 'bold' } ]], :first, :second)
+      options_from_collection_for_select([[ "USA", "USA", { class: "bold" } ]], :first, :second)
     )
   end
 
@@ -147,8 +157,8 @@ class FormOptionsHelperTest < ActionView::TestCase
     assert_dom_equal(
       "<option selected=\"selected\" type=\"Coach\" value=\"1\">Richard Bandler</option>\n<option type=\"Coachee\" value=\"1\">Richard Bandler</option>",
       options_for_select([
-        ['Richard Bandler', 1, { type: 'Coach', selected: 'selected' }],
-        ['Richard Bandler', 1, { type: 'Coachee' }]
+        ["Richard Bandler", 1, { type: "Coach", selected: "selected" }],
+        ["Richard Bandler", 1, { type: "Coachee" }]
       ])
     )
   end
@@ -157,8 +167,8 @@ class FormOptionsHelperTest < ActionView::TestCase
     assert_dom_equal(
       "<option disabled=\"disabled\" type=\"Coach\" value=\"1\">Richard Bandler</option>\n<option type=\"Coachee\" value=\"1\">Richard Bandler</option>",
       options_for_select([
-        ['Richard Bandler', 1, { type: 'Coach', disabled: 'disabled' }],
-        ['Richard Bandler', 1, { type: 'Coachee' }]
+        ["Richard Bandler", 1, { type: "Coach", disabled: "disabled" }],
+        ["Richard Bandler", 1, { type: "Coachee" }]
       ])
     )
   end
@@ -171,37 +181,37 @@ class FormOptionsHelperTest < ActionView::TestCase
   end
 
   def test_array_options_for_select_with_selection_array
-      assert_dom_equal(
-        "<option value=\"Denmark\">Denmark</option>\n<option value=\"&lt;USA&gt;\" selected=\"selected\">&lt;USA&gt;</option>\n<option value=\"Sweden\" selected=\"selected\">Sweden</option>",
-        options_for_select([ "Denmark", "<USA>", "Sweden" ], [ "<USA>", "Sweden" ])
-      )
+    assert_dom_equal(
+      "<option value=\"Denmark\">Denmark</option>\n<option value=\"&lt;USA&gt;\" selected=\"selected\">&lt;USA&gt;</option>\n<option value=\"Sweden\" selected=\"selected\">Sweden</option>",
+      options_for_select([ "Denmark", "<USA>", "Sweden" ], [ "<USA>", "Sweden" ])
+    )
   end
 
   def test_array_options_for_select_with_disabled_value
     assert_dom_equal(
       "<option value=\"Denmark\">Denmark</option>\n<option value=\"&lt;USA&gt;\" disabled=\"disabled\">&lt;USA&gt;</option>\n<option value=\"Sweden\">Sweden</option>",
-      options_for_select([ "Denmark", "<USA>", "Sweden" ], :disabled => "<USA>")
+      options_for_select([ "Denmark", "<USA>", "Sweden" ], disabled: "<USA>")
     )
   end
 
   def test_array_options_for_select_with_disabled_array
     assert_dom_equal(
       "<option value=\"Denmark\">Denmark</option>\n<option value=\"&lt;USA&gt;\" disabled=\"disabled\">&lt;USA&gt;</option>\n<option value=\"Sweden\" disabled=\"disabled\">Sweden</option>",
-      options_for_select([ "Denmark", "<USA>", "Sweden" ], :disabled => ["<USA>", "Sweden"])
+      options_for_select([ "Denmark", "<USA>", "Sweden" ], disabled: ["<USA>", "Sweden"])
     )
   end
 
   def test_array_options_for_select_with_selection_and_disabled_value
     assert_dom_equal(
       "<option value=\"Denmark\" selected=\"selected\">Denmark</option>\n<option value=\"&lt;USA&gt;\" disabled=\"disabled\">&lt;USA&gt;</option>\n<option value=\"Sweden\">Sweden</option>",
-      options_for_select([ "Denmark", "<USA>", "Sweden" ], :selected => "Denmark", :disabled => "<USA>")
+      options_for_select([ "Denmark", "<USA>", "Sweden" ], selected: "Denmark", disabled: "<USA>")
     )
   end
 
   def test_boolean_array_options_for_select_with_selection_and_disabled_value
     assert_dom_equal(
       "<option value=\"true\">true</option>\n<option value=\"false\" selected=\"selected\">false</option>",
-      options_for_select([ true, false ], :selected => false, :disabled => nil)
+      options_for_select([ true, false ], selected: false, disabled: nil)
     )
   end
 
@@ -213,18 +223,18 @@ class FormOptionsHelperTest < ActionView::TestCase
   end
 
   def test_array_options_for_string_include_in_other_string_bug_fix
-      assert_dom_equal(
-        "<option value=\"ruby\">ruby</option>\n<option value=\"rubyonrails\" selected=\"selected\">rubyonrails</option>",
-        options_for_select([ "ruby", "rubyonrails" ], "rubyonrails")
-      )
-      assert_dom_equal(
-        "<option value=\"ruby\" selected=\"selected\">ruby</option>\n<option value=\"rubyonrails\">rubyonrails</option>",
-        options_for_select([ "ruby", "rubyonrails" ], "ruby")
-      )
-      assert_dom_equal(
-        %(<option value="ruby" selected="selected">ruby</option>\n<option value="rubyonrails">rubyonrails</option>\n<option value=""></option>),
-        options_for_select([ "ruby", "rubyonrails", nil ], "ruby")
-      )
+    assert_dom_equal(
+      "<option value=\"ruby\">ruby</option>\n<option value=\"rubyonrails\" selected=\"selected\">rubyonrails</option>",
+      options_for_select([ "ruby", "rubyonrails" ], "rubyonrails")
+    )
+    assert_dom_equal(
+      "<option value=\"ruby\" selected=\"selected\">ruby</option>\n<option value=\"rubyonrails\">rubyonrails</option>",
+      options_for_select([ "ruby", "rubyonrails" ], "ruby")
+    )
+    assert_dom_equal(
+      %(<option value="ruby" selected="selected">ruby</option>\n<option value="rubyonrails">rubyonrails</option>\n<option value=""></option>),
+      options_for_select([ "ruby", "rubyonrails", nil ], "ruby")
+    )
   end
 
   def test_hash_options_for_select
@@ -259,64 +269,64 @@ class FormOptionsHelperTest < ActionView::TestCase
   end
 
   def test_collection_options_with_preselected_value_as_string_and_option_value_is_integer
-    albums = [ Album.new(1, "first","rap"), Album.new(2, "second","pop")]
+    albums = [ Album.new(1, "first", "rap"), Album.new(2, "second", "pop")]
     assert_dom_equal(
-    %(<option selected="selected" value="1">rap</option>\n<option value="2">pop</option>),
-    options_from_collection_for_select(albums, "id", "genre", :selected => "1")
+      %(<option selected="selected" value="1">rap</option>\n<option value="2">pop</option>),
+      options_from_collection_for_select(albums, "id", "genre", selected: "1")
     )
   end
 
   def test_collection_options_with_preselected_value_as_integer_and_option_value_is_string
-    albums = [ Album.new("1", "first","rap"), Album.new("2", "second","pop")]
+    albums = [ Album.new("1", "first", "rap"), Album.new("2", "second", "pop")]
 
     assert_dom_equal(
-    %(<option selected="selected" value="1">rap</option>\n<option value="2">pop</option>),
-    options_from_collection_for_select(albums, "id", "genre", :selected => 1)
+      %(<option selected="selected" value="1">rap</option>\n<option value="2">pop</option>),
+      options_from_collection_for_select(albums, "id", "genre", selected: 1)
     )
   end
 
   def test_collection_options_with_preselected_value_as_string_and_option_value_is_float
-    albums = [ Album.new(1.0, "first","rap"), Album.new(2.0, "second","pop")]
+    albums = [ Album.new(1.0, "first", "rap"), Album.new(2.0, "second", "pop")]
 
     assert_dom_equal(
-    %(<option value="1.0">rap</option>\n<option value="2.0" selected="selected">pop</option>),
-    options_from_collection_for_select(albums, "id", "genre", :selected => "2.0")
+      %(<option value="1.0">rap</option>\n<option value="2.0" selected="selected">pop</option>),
+      options_from_collection_for_select(albums, "id", "genre", selected: "2.0")
     )
   end
 
   def test_collection_options_with_preselected_value_as_nil
-    albums = [ Album.new(1.0, "first","rap"), Album.new(2.0, "second","pop")]
+    albums = [ Album.new(1.0, "first", "rap"), Album.new(2.0, "second", "pop")]
 
     assert_dom_equal(
-    %(<option value="1.0">rap</option>\n<option value="2.0">pop</option>),
-    options_from_collection_for_select(albums, "id", "genre", :selected => nil)
+      %(<option value="1.0">rap</option>\n<option value="2.0">pop</option>),
+      options_from_collection_for_select(albums, "id", "genre", selected: nil)
     )
   end
 
   def test_collection_options_with_disabled_value_as_nil
-    albums = [ Album.new(1.0, "first","rap"), Album.new(2.0, "second","pop")]
+    albums = [ Album.new(1.0, "first", "rap"), Album.new(2.0, "second", "pop")]
 
     assert_dom_equal(
-    %(<option value="1.0">rap</option>\n<option value="2.0">pop</option>),
-    options_from_collection_for_select(albums, "id", "genre", :disabled => nil)
+      %(<option value="1.0">rap</option>\n<option value="2.0">pop</option>),
+      options_from_collection_for_select(albums, "id", "genre", disabled: nil)
     )
   end
 
   def test_collection_options_with_disabled_value_as_array
-    albums = [ Album.new(1.0, "first","rap"), Album.new(2.0, "second","pop")]
+    albums = [ Album.new(1.0, "first", "rap"), Album.new(2.0, "second", "pop")]
 
     assert_dom_equal(
-    %(<option disabled="disabled" value="1.0">rap</option>\n<option disabled="disabled" value="2.0">pop</option>),
-    options_from_collection_for_select(albums, "id", "genre", :disabled => ["1.0", 2.0])
+      %(<option disabled="disabled" value="1.0">rap</option>\n<option disabled="disabled" value="2.0">pop</option>),
+      options_from_collection_for_select(albums, "id", "genre", disabled: ["1.0", 2.0])
     )
   end
 
   def test_collection_options_with_preselected_values_as_string_array_and_option_value_is_float
-    albums = [ Album.new(1.0, "first","rap"), Album.new(2.0, "second","pop"), Album.new(3.0, "third","country") ]
+    albums = [ Album.new(1.0, "first", "rap"), Album.new(2.0, "second", "pop"), Album.new(3.0, "third", "country") ]
 
     assert_dom_equal(
-    %(<option value="1.0" selected="selected">rap</option>\n<option value="2.0">pop</option>\n<option value="3.0" selected="selected">country</option>),
-    options_from_collection_for_select(albums, "id", "genre", ["1.0","3.0"])
+      %(<option value="1.0" selected="selected">rap</option>\n<option value="2.0">pop</option>\n<option value="3.0" selected="selected">country</option>),
+      options_from_collection_for_select(albums, "id", "genre", ["1.0", "3.0"])
     )
   end
 
@@ -327,6 +337,22 @@ class FormOptionsHelperTest < ActionView::TestCase
     )
   end
 
+  def test_option_groups_from_collection_for_select_with_callable_group_method
+    group_proc = Proc.new { |c| c.countries }
+    assert_dom_equal(
+      "<optgroup label=\"&lt;Africa&gt;\"><option value=\"&lt;sa&gt;\">&lt;South Africa&gt;</option>\n<option value=\"so\">Somalia</option></optgroup><optgroup label=\"Europe\"><option value=\"dk\" selected=\"selected\">Denmark</option>\n<option value=\"ie\">Ireland</option></optgroup>",
+      option_groups_from_collection_for_select(dummy_continents, group_proc, "continent_name", "country_id", "country_name", "dk")
+    )
+  end
+
+  def test_option_groups_from_collection_for_select_with_callable_group_label_method
+    label_proc = Proc.new { |c| c.continent_name }
+    assert_dom_equal(
+      "<optgroup label=\"&lt;Africa&gt;\"><option value=\"&lt;sa&gt;\">&lt;South Africa&gt;</option>\n<option value=\"so\">Somalia</option></optgroup><optgroup label=\"Europe\"><option value=\"dk\" selected=\"selected\">Denmark</option>\n<option value=\"ie\">Ireland</option></optgroup>",
+      option_groups_from_collection_for_select(dummy_continents, "countries", label_proc, "country_id", "country_name", "dk")
+    )
+  end
+
   def test_option_groups_from_collection_for_select_returns_html_safe_string
     assert option_groups_from_collection_for_select(dummy_continents, "countries", "continent_name", "country_id", "country_name", "dk").html_safe?
   end
@@ -336,9 +362,9 @@ class FormOptionsHelperTest < ActionView::TestCase
       "<optgroup label=\"North America\"><option value=\"US\">United States</option>\n<option value=\"Canada\">Canada</option></optgroup><optgroup label=\"Europe\"><option value=\"GB\">Great Britain</option>\n<option value=\"Germany\">Germany</option></optgroup>",
       grouped_options_for_select([
          ["North America",
-             [['United States','US'],"Canada"]],
+             [["United States", "US"], "Canada"]],
          ["Europe",
-             [["Great Britain","GB"], "Germany"]]
+             [["Great Britain", "GB"], "Germany"]]
        ])
     )
   end
@@ -347,8 +373,8 @@ class FormOptionsHelperTest < ActionView::TestCase
     assert_dom_equal(
       "<optgroup label=\"North America\" data-foo=\"bar\"><option value=\"US\">United States</option>\n<option value=\"Canada\">Canada</option></optgroup><optgroup label=\"Europe\" disabled=\"disabled\"><option value=\"GB\">Great Britain</option>\n<option value=\"Germany\">Germany</option></optgroup>",
       grouped_options_for_select([
-         ["North America", [['United States','US'],"Canada"], :data => { :foo => 'bar' }],
-         ["Europe", [["Great Britain","GB"], "Germany"], :disabled => 'disabled']
+         ["North America", [["United States", "US"], "Canada"], data: { foo: "bar" }],
+         ["Europe", [["Great Britain", "GB"], "Germany"], disabled: "disabled"]
        ])
     )
   end
@@ -357,110 +383,110 @@ class FormOptionsHelperTest < ActionView::TestCase
     assert_dom_equal(
       "<optgroup label=\"----------\"><option value=\"US\">US</option>\n<option value=\"Canada\">Canada</option></optgroup><optgroup label=\"----------\"><option value=\"GB\">GB</option>\n<option value=\"Germany\">Germany</option></optgroup>",
 
-      grouped_options_for_select([['US',"Canada"] , ["GB", "Germany"]], nil, divider: "----------")
+      grouped_options_for_select([["US", "Canada"], ["GB", "Germany"]], nil, divider: "----------")
     )
   end
 
   def test_grouped_options_for_select_with_selected_and_prompt
     assert_dom_equal(
-        "<option value=\"\">Choose a product...</option><optgroup label=\"Hats\"><option value=\"Baseball Cap\">Baseball Cap</option>\n<option selected=\"selected\" value=\"Cowboy Hat\">Cowboy Hat</option></optgroup>",
-        grouped_options_for_select([["Hats", ["Baseball Cap","Cowboy Hat"]]], "Cowboy Hat", prompt: "Choose a product...")
+      "<option value=\"\">Choose a product...</option><optgroup label=\"Hats\"><option value=\"Baseball Cap\">Baseball Cap</option>\n<option selected=\"selected\" value=\"Cowboy Hat\">Cowboy Hat</option></optgroup>",
+      grouped_options_for_select([["Hats", ["Baseball Cap", "Cowboy Hat"]]], "Cowboy Hat", prompt: "Choose a product...")
     )
   end
 
   def test_grouped_options_for_select_with_selected_and_prompt_true
     assert_dom_equal(
-        "<option value=\"\">Please select</option><optgroup label=\"Hats\"><option value=\"Baseball Cap\">Baseball Cap</option>\n<option selected=\"selected\" value=\"Cowboy Hat\">Cowboy Hat</option></optgroup>",
-        grouped_options_for_select([["Hats", ["Baseball Cap","Cowboy Hat"]]], "Cowboy Hat", prompt: true)
+      "<option value=\"\">Please select</option><optgroup label=\"Hats\"><option value=\"Baseball Cap\">Baseball Cap</option>\n<option selected=\"selected\" value=\"Cowboy Hat\">Cowboy Hat</option></optgroup>",
+      grouped_options_for_select([["Hats", ["Baseball Cap", "Cowboy Hat"]]], "Cowboy Hat", prompt: true)
     )
   end
 
   def test_grouped_options_for_select_returns_html_safe_string
-    assert grouped_options_for_select([["Hats", ["Baseball Cap","Cowboy Hat"]]]).html_safe?
+    assert grouped_options_for_select([["Hats", ["Baseball Cap", "Cowboy Hat"]]]).html_safe?
   end
 
   def test_grouped_options_for_select_with_prompt_returns_html_escaped_string
     assert_dom_equal(
       "<option value=\"\">&lt;Choose One&gt;</option><optgroup label=\"Hats\"><option value=\"Baseball Cap\">Baseball Cap</option>\n<option value=\"Cowboy Hat\">Cowboy Hat</option></optgroup>",
-      grouped_options_for_select([["Hats", ["Baseball Cap","Cowboy Hat"]]], nil, prompt: '<Choose One>'))
+      grouped_options_for_select([["Hats", ["Baseball Cap", "Cowboy Hat"]]], nil, prompt: "<Choose One>"))
   end
 
   def test_optgroups_with_with_options_with_hash
     assert_dom_equal(
-       "<optgroup label=\"North America\"><option value=\"United States\">United States</option>\n<option value=\"Canada\">Canada</option></optgroup><optgroup label=\"Europe\"><option value=\"Denmark\">Denmark</option>\n<option value=\"Germany\">Germany</option></optgroup>",
-       grouped_options_for_select({'North America' => ['United States','Canada'], 'Europe' => ['Denmark','Germany']})
+      "<optgroup label=\"North America\"><option value=\"United States\">United States</option>\n<option value=\"Canada\">Canada</option></optgroup><optgroup label=\"Europe\"><option value=\"Denmark\">Denmark</option>\n<option value=\"Germany\">Germany</option></optgroup>",
+      grouped_options_for_select("North America" => ["United States", "Canada"], "Europe" => ["Denmark", "Germany"])
     )
   end
 
   def test_time_zone_options_no_params
     opts = time_zone_options_for_select
-    assert_dom_equal "<option value=\"A\">A</option>\n" +
-                 "<option value=\"B\">B</option>\n" +
-                 "<option value=\"C\">C</option>\n" +
-                 "<option value=\"D\">D</option>\n" +
+    assert_dom_equal "<option value=\"A\">A</option>\n" \
+                 "<option value=\"B\">B</option>\n" \
+                 "<option value=\"C\">C</option>\n" \
+                 "<option value=\"D\">D</option>\n" \
                  "<option value=\"E\">E</option>",
                  opts
   end
 
   def test_time_zone_options_with_selected
-    opts = time_zone_options_for_select( "D" )
-    assert_dom_equal "<option value=\"A\">A</option>\n" +
-                 "<option value=\"B\">B</option>\n" +
-                 "<option value=\"C\">C</option>\n" +
-                 "<option value=\"D\" selected=\"selected\">D</option>\n" +
+    opts = time_zone_options_for_select("D")
+    assert_dom_equal "<option value=\"A\">A</option>\n" \
+                 "<option value=\"B\">B</option>\n" \
+                 "<option value=\"C\">C</option>\n" \
+                 "<option value=\"D\" selected=\"selected\">D</option>\n" \
                  "<option value=\"E\">E</option>",
                  opts
   end
 
   def test_time_zone_options_with_unknown_selected
-    opts = time_zone_options_for_select( "K" )
-    assert_dom_equal "<option value=\"A\">A</option>\n" +
-                 "<option value=\"B\">B</option>\n" +
-                 "<option value=\"C\">C</option>\n" +
-                 "<option value=\"D\">D</option>\n" +
+    opts = time_zone_options_for_select("K")
+    assert_dom_equal "<option value=\"A\">A</option>\n" \
+                 "<option value=\"B\">B</option>\n" \
+                 "<option value=\"C\">C</option>\n" \
+                 "<option value=\"D\">D</option>\n" \
                  "<option value=\"E\">E</option>",
                  opts
   end
 
   def test_time_zone_options_with_priority_zones
-    zones = [ ActiveSupport::TimeZone.new( "B" ), ActiveSupport::TimeZone.new( "E" ) ]
-    opts = time_zone_options_for_select( nil, zones )
-    assert_dom_equal "<option value=\"B\">B</option>\n" +
-                 "<option value=\"E\">E</option>" +
-                 "<option value=\"\" disabled=\"disabled\">-------------</option>\n" +
-                 "<option value=\"A\">A</option>\n" +
-                 "<option value=\"C\">C</option>\n" +
+    zones = [ ActiveSupport::TimeZone.new("B"), ActiveSupport::TimeZone.new("E") ]
+    opts = time_zone_options_for_select(nil, zones)
+    assert_dom_equal "<option value=\"B\">B</option>\n" \
+                 "<option value=\"E\">E</option>" \
+                 "<option value=\"\" disabled=\"disabled\">-------------</option>\n" \
+                 "<option value=\"A\">A</option>\n" \
+                 "<option value=\"C\">C</option>\n" \
                  "<option value=\"D\">D</option>",
                  opts
   end
 
   def test_time_zone_options_with_selected_priority_zones
-    zones = [ ActiveSupport::TimeZone.new( "B" ), ActiveSupport::TimeZone.new( "E" ) ]
-    opts = time_zone_options_for_select( "E", zones )
-    assert_dom_equal "<option value=\"B\">B</option>\n" +
-                 "<option value=\"E\" selected=\"selected\">E</option>" +
-                 "<option value=\"\" disabled=\"disabled\">-------------</option>\n" +
-                 "<option value=\"A\">A</option>\n" +
-                 "<option value=\"C\">C</option>\n" +
+    zones = [ ActiveSupport::TimeZone.new("B"), ActiveSupport::TimeZone.new("E") ]
+    opts = time_zone_options_for_select("E", zones)
+    assert_dom_equal "<option value=\"B\">B</option>\n" \
+                 "<option value=\"E\" selected=\"selected\">E</option>" \
+                 "<option value=\"\" disabled=\"disabled\">-------------</option>\n" \
+                 "<option value=\"A\">A</option>\n" \
+                 "<option value=\"C\">C</option>\n" \
                  "<option value=\"D\">D</option>",
                  opts
   end
 
   def test_time_zone_options_with_unselected_priority_zones
-    zones = [ ActiveSupport::TimeZone.new( "B" ), ActiveSupport::TimeZone.new( "E" ) ]
-    opts = time_zone_options_for_select( "C", zones )
-    assert_dom_equal "<option value=\"B\">B</option>\n" +
-                 "<option value=\"E\">E</option>" +
-                 "<option value=\"\" disabled=\"disabled\">-------------</option>\n" +
-                 "<option value=\"A\">A</option>\n" +
-                 "<option value=\"C\" selected=\"selected\">C</option>\n" +
+    zones = [ ActiveSupport::TimeZone.new("B"), ActiveSupport::TimeZone.new("E") ]
+    opts = time_zone_options_for_select("C", zones)
+    assert_dom_equal "<option value=\"B\">B</option>\n" \
+                 "<option value=\"E\">E</option>" \
+                 "<option value=\"\" disabled=\"disabled\">-------------</option>\n" \
+                 "<option value=\"A\">A</option>\n" \
+                 "<option value=\"C\" selected=\"selected\">C</option>\n" \
                  "<option value=\"D\">D</option>",
                  opts
   end
 
   def test_time_zone_options_with_priority_zones_does_not_mutate_time_zones
     original_zones = ActiveSupport::TimeZone.all.dup
-    zones = [ ActiveSupport::TimeZone.new( "B" ), ActiveSupport::TimeZone.new( "E" ) ]
+    zones = [ ActiveSupport::TimeZone.new("B"), ActiveSupport::TimeZone.new("E") ]
     time_zone_options_for_select(nil, zones)
     assert_equal original_zones, ActiveSupport::TimeZone.all
   end
@@ -481,7 +507,7 @@ class FormOptionsHelperTest < ActionView::TestCase
   def test_select_without_multiple
     assert_dom_equal(
       "<select id=\"post_category\" name=\"post[category]\"></select>",
-      select(:post, :category, "", {}, :multiple => false)
+      select(:post, :category, "", {}, { multiple: false })
     )
   end
 
@@ -495,9 +521,9 @@ class FormOptionsHelperTest < ActionView::TestCase
 
     assert_dom_equal(
       [
-        %Q{<select id="post_origin" name="post[origin]"><optgroup label="&lt;Africa&gt;"><option value="&lt;sa&gt;">&lt;South Africa&gt;</option>},
-        %Q{<option value="so">Somalia</option></optgroup><optgroup label="Europe"><option value="dk">Denmark</option>},
-        %Q{<option value="ie">Ireland</option></optgroup></select>},
+        '<select id="post_origin" name="post[origin]"><optgroup label="&lt;Africa&gt;"><option value="&lt;sa&gt;">&lt;South Africa&gt;</option>',
+        '<option value="so">Somalia</option></optgroup><optgroup label="Europe"><option value="dk">Denmark</option>',
+        '<option value="ie">Ireland</option></optgroup></select>',
       ].join("\n"),
       select("post", "origin", countries_by_continent)
     )
@@ -513,9 +539,9 @@ class FormOptionsHelperTest < ActionView::TestCase
 
     assert_dom_equal(
       [
-        %Q{<select id="post_origin" name="post[origin]"><optgroup label="&lt;Africa&gt;"><option value="&lt;sa&gt;">&lt;South Africa&gt;</option>},
-        %Q{<option value="so">Somalia</option></optgroup><optgroup label="Europe"><option value="dk">Denmark</option>},
-        %Q{<option value="ie">Ireland</option></optgroup></select>},
+        '<select id="post_origin" name="post[origin]"><optgroup label="&lt;Africa&gt;"><option value="&lt;sa&gt;">&lt;South Africa&gt;</option>',
+        '<option value="so">Somalia</option></optgroup><optgroup label="Europe"><option value="dk">Denmark</option>',
+        '<option value="ie">Ireland</option></optgroup></select>',
       ].join("\n"),
       select("post", "origin", countries_by_continent)
     )
@@ -561,7 +587,7 @@ class FormOptionsHelperTest < ActionView::TestCase
     @post = Post.new
     @post.category = "<mus>"
 
-    output_buffer = fields_for :post, @post, :index => 108 do |f|
+    output_buffer = fields_for :post, @post, index: 108 do |f|
       concat f.select(:category, %w( abe <mus> hest))
     end
 
@@ -591,7 +617,7 @@ class FormOptionsHelperTest < ActionView::TestCase
     options = raw("<option value=\"abe\">abe</option><option value=\"mus\">mus</option><option value=\"hest\">hest</option>")
 
     output_buffer = fields_for :post, @post do |f|
-      concat f.select(:category, options, :prompt => 'The prompt')
+      concat f.select(:category, options, prompt: "The prompt")
     end
 
     assert_dom_equal(
@@ -629,7 +655,7 @@ class FormOptionsHelperTest < ActionView::TestCase
   end
 
   def test_select_with_multiple_to_add_hidden_input
-    output_buffer =  select(:post, :category, "", {}, :multiple => true)
+    output_buffer = select(:post, :category, "", {}, { multiple: true })
     assert_dom_equal(
       "<input type=\"hidden\" name=\"post[category][]\" value=\"\"/><select multiple=\"multiple\" id=\"post_category\" name=\"post[category][]\"></select>",
       output_buffer
@@ -637,7 +663,7 @@ class FormOptionsHelperTest < ActionView::TestCase
   end
 
   def test_select_with_multiple_and_without_hidden_input
-    output_buffer =  select(:post, :category, "", {:include_hidden => false}, :multiple => true)
+    output_buffer = select(:post, :category, "", { include_hidden: false }, { multiple: true })
     assert_dom_equal(
       "<select multiple=\"multiple\" id=\"post_category\" name=\"post[category][]\"></select>",
       output_buffer
@@ -645,7 +671,7 @@ class FormOptionsHelperTest < ActionView::TestCase
   end
 
   def test_select_with_multiple_and_with_explicit_name_ending_with_brackets
-    output_buffer =  select(:post, :category, [], {include_hidden: false}, multiple: true, name: 'post[category][]')
+    output_buffer = select(:post, :category, [], { include_hidden: false }, { multiple: true, name: "post[category][]" })
     assert_dom_equal(
       "<select multiple=\"multiple\" id=\"post_category\" name=\"post[category][]\"></select>",
       output_buffer
@@ -653,7 +679,7 @@ class FormOptionsHelperTest < ActionView::TestCase
   end
 
   def test_select_with_multiple_and_disabled_to_add_disabled_hidden_input
-    output_buffer =  select(:post, :category, "", {}, :multiple => true, :disabled => true)
+    output_buffer = select(:post, :category, "", {}, { multiple: true, disabled: true })
     assert_dom_equal(
       "<input disabled=\"disabled\"type=\"hidden\" name=\"post[category][]\" value=\"\"/><select multiple=\"multiple\" disabled=\"disabled\" id=\"post_category\" name=\"post[category][]\"></select>",
       output_buffer
@@ -665,14 +691,14 @@ class FormOptionsHelperTest < ActionView::TestCase
     @post.category = "<mus>"
     assert_dom_equal(
       "<select id=\"post_category\" name=\"post[category]\"><option value=\"\"></option>\n<option value=\"abe\">abe</option>\n<option value=\"&lt;mus&gt;\" selected=\"selected\">&lt;mus&gt;</option>\n<option value=\"hest\">hest</option></select>",
-      select("post", "category", %w( abe <mus> hest), :include_blank => true)
+      select("post", "category", %w( abe <mus> hest), include_blank: true)
     )
   end
 
   def test_select_with_include_blank_false_and_required
     @post = Post.new
     @post.category = "<mus>"
-    e = assert_raises(ArgumentError) { select("post", "category", %w( abe <mus> hest), { include_blank: false }, required: 'required') }
+    e = assert_raises(ArgumentError) { select("post", "category", %w( abe <mus> hest), { include_blank: false }, { required: "required" }) }
     assert_match(/include_blank cannot be false for a required field./, e.message)
   end
 
@@ -681,7 +707,7 @@ class FormOptionsHelperTest < ActionView::TestCase
     @post.category = "<mus>"
     assert_dom_equal(
       "<select id=\"post_category\" name=\"post[category]\"><option value=\"\">None</option>\n<option value=\"abe\">abe</option>\n<option value=\"&lt;mus&gt;\" selected=\"selected\">&lt;mus&gt;</option>\n<option value=\"hest\">hest</option></select>",
-      select("post", "category", %w( abe <mus> hest), :include_blank => 'None')
+      select("post", "category", %w( abe <mus> hest), include_blank: "None")
     )
   end
 
@@ -690,7 +716,7 @@ class FormOptionsHelperTest < ActionView::TestCase
     @post.category = "<mus>"
     assert_dom_equal(
       "<select id=\"post_category\" name=\"post[category]\"><option value=\"\">&lt;None&gt;</option>\n<option value=\"abe\">abe</option>\n<option value=\"&lt;mus&gt;\" selected=\"selected\">&lt;mus&gt;</option>\n<option value=\"hest\">hest</option></select>",
-      select("post", "category", %w( abe <mus> hest), :include_blank => '<None>')
+      select("post", "category", %w( abe <mus> hest), include_blank: "<None>")
     )
   end
 
@@ -699,7 +725,7 @@ class FormOptionsHelperTest < ActionView::TestCase
     @post.category = ""
     assert_dom_equal(
       "<select id=\"post_category\" name=\"post[category]\"><option value=\"\">Please select</option>\n<option value=\"abe\">abe</option>\n<option value=\"&lt;mus&gt;\">&lt;mus&gt;</option>\n<option value=\"hest\">hest</option></select>",
-      select("post", "category", %w( abe <mus> hest), :prompt => true)
+      select("post", "category", %w( abe <mus> hest), prompt: true)
     )
   end
 
@@ -708,7 +734,7 @@ class FormOptionsHelperTest < ActionView::TestCase
     @post.category = "<mus>"
     assert_dom_equal(
       "<select id=\"post_category\" name=\"post[category]\"><option value=\"abe\">abe</option>\n<option value=\"&lt;mus&gt;\" selected=\"selected\">&lt;mus&gt;</option>\n<option value=\"hest\">hest</option></select>",
-      select("post", "category", %w( abe <mus> hest), :prompt => true)
+      select("post", "category", %w( abe <mus> hest), prompt: true)
     )
   end
 
@@ -717,7 +743,7 @@ class FormOptionsHelperTest < ActionView::TestCase
     @post.category = ""
     assert_dom_equal(
       "<select id=\"post_category\" name=\"post[category]\"><option value=\"\">The prompt</option>\n<option value=\"abe\">abe</option>\n<option value=\"&lt;mus&gt;\">&lt;mus&gt;</option>\n<option value=\"hest\">hest</option></select>",
-      select("post", "category", %w( abe <mus> hest), :prompt => 'The prompt')
+      select("post", "category", %w( abe <mus> hest), prompt: "The prompt")
     )
   end
 
@@ -725,7 +751,7 @@ class FormOptionsHelperTest < ActionView::TestCase
     @post = Post.new
     assert_dom_equal(
       "<select id=\"post_category\" name=\"post[category]\"><option value=\"\">&lt;The prompt&gt;</option>\n<option value=\"abe\">abe</option>\n<option value=\"&lt;mus&gt;\">&lt;mus&gt;</option>\n<option value=\"hest\">hest</option></select>",
-      select("post", "category", %w( abe <mus> hest), :prompt => '<The prompt>')
+      select("post", "category", %w( abe <mus> hest), prompt: "<The prompt>")
     )
   end
 
@@ -734,16 +760,25 @@ class FormOptionsHelperTest < ActionView::TestCase
     @post.category = ""
     assert_dom_equal(
       "<select id=\"post_category\" name=\"post[category]\"><option value=\"\">Please select</option>\n<option value=\"\"></option>\n<option value=\"abe\">abe</option>\n<option value=\"&lt;mus&gt;\">&lt;mus&gt;</option>\n<option value=\"hest\">hest</option></select>",
-      select("post", "category", %w( abe <mus> hest), :prompt => true, :include_blank => true)
+      select("post", "category", %w( abe <mus> hest), prompt: true, include_blank: true)
     )
   end
 
-  def test_empty
+  def test_select_with_empty
     @post = Post.new
     @post.category = ""
     assert_dom_equal(
       "<select id=\"post_category\" name=\"post[category]\"><option value=\"\">Please select</option>\n<option value=\"\"></option>\n</select>",
-      select("post", "category", [], :prompt => true, :include_blank => true)
+      select("post", "category", [], prompt: true, include_blank: true)
+    )
+  end
+
+  def test_select_with_html_options
+    @post = Post.new
+    @post.category = ""
+    assert_dom_equal(
+      "<select class=\"disabled\" disabled=\"disabled\" name=\"post[category]\" id=\"post_category\"><option value=\"\">Please select</option>\n<option value=\"\"></option>\n</select>",
+      select("post", "category", [], { prompt: true, include_blank: true }, { class: "disabled", disabled: true })
     )
   end
 
@@ -759,42 +794,42 @@ class FormOptionsHelperTest < ActionView::TestCase
   def test_required_select
     assert_dom_equal(
       %(<select id="post_category" name="post[category]" required="required"><option value=""></option>\n<option value="abe">abe</option>\n<option value="mus">mus</option>\n<option value="hest">hest</option></select>),
-      select("post", "category", %w(abe mus hest), {}, required: true)
+      select("post", "category", %w(abe mus hest), {}, { required: true })
     )
   end
 
   def test_required_select_with_include_blank_prompt
     assert_dom_equal(
       %(<select id="post_category" name="post[category]" required="required"><option value="">Select one</option>\n<option value="abe">abe</option>\n<option value="mus">mus</option>\n<option value="hest">hest</option></select>),
-      select("post", "category", %w(abe mus hest), { include_blank: "Select one" }, required: true)
+      select("post", "category", %w(abe mus hest), { include_blank: "Select one" }, { required: true })
     )
   end
 
   def test_required_select_with_prompt
     assert_dom_equal(
       %(<select id="post_category" name="post[category]" required="required"><option value="">Select one</option>\n<option value="abe">abe</option>\n<option value="mus">mus</option>\n<option value="hest">hest</option></select>),
-      select("post", "category", %w(abe mus hest), { prompt: "Select one" }, required: true)
+      select("post", "category", %w(abe mus hest), { prompt: "Select one" }, { required: true })
     )
   end
 
   def test_required_select_display_size_equals_to_one
     assert_dom_equal(
       %(<select id="post_category" name="post[category]" required="required" size="1"><option value=""></option>\n<option value="abe">abe</option>\n<option value="mus">mus</option>\n<option value="hest">hest</option></select>),
-      select("post", "category", %w(abe mus hest), {}, required: true, size: 1)
+      select("post", "category", %w(abe mus hest), {}, { required: true, size: 1 })
     )
   end
 
   def test_required_select_with_display_size_bigger_than_one
     assert_dom_equal(
       %(<select id="post_category" name="post[category]" required="required" size="2"><option value="abe">abe</option>\n<option value="mus">mus</option>\n<option value="hest">hest</option></select>),
-      select("post", "category", %w(abe mus hest), {}, required: true, size: 2)
+      select("post", "category", %w(abe mus hest), {}, { required: true, size: 2 })
     )
   end
 
   def test_required_select_with_multiple_option
     assert_dom_equal(
       %(<input name="post[category][]" type="hidden" value=""/><select id="post_category" multiple="multiple" name="post[category][]" required="required"><option value="abe">abe</option>\n<option value="mus">mus</option>\n<option value="hest">hest</option></select>),
-      select("post", "category", %w(abe mus hest), {}, required: true, multiple: true)
+      select("post", "category", %w(abe mus hest), {}, { required: true, multiple: true })
     )
   end
 
@@ -803,7 +838,7 @@ class FormOptionsHelperTest < ActionView::TestCase
     @post.category = ""
     assert_dom_equal(
       "<select id=\"post_category\" name=\"post[category]\"><option value=\"\">Please select</option>\n<option value=\"\"></option>\n<option value=\"1\">1</option></select>",
-      select("post", "category", [1], :prompt => true, :include_blank => true)
+      select("post", "category", [1], prompt: true, include_blank: true)
     )
   end
 
@@ -812,7 +847,7 @@ class FormOptionsHelperTest < ActionView::TestCase
     @post.category = ""
     assert_dom_equal(
       "<select id=\"post_category\" name=\"post[category]\"><option value=\"\">Please select</option>\n<option value=\"\"></option>\n<option value=\"number\">Number</option>\n<option value=\"text\">Text</option>\n<option value=\"boolean\">Yes/No</option></select>",
-      select("post", "category", [["Number", "number"], ["Text", "text"], ["Yes/No", "boolean"]], :prompt => true, :include_blank => true)
+      select("post", "category", [["Number", "number"], ["Text", "text"], ["Yes/No", "boolean"]], prompt: true, include_blank: true)
     )
   end
 
@@ -821,7 +856,7 @@ class FormOptionsHelperTest < ActionView::TestCase
     @post.category = "<mus>"
     assert_dom_equal(
       "<select id=\"post_category\" name=\"post[category]\"><option value=\"abe\" selected=\"selected\">abe</option>\n<option value=\"&lt;mus&gt;\">&lt;mus&gt;</option>\n<option value=\"hest\">hest</option></select>",
-      select("post", "category", %w( abe <mus> hest ), :selected => 'abe')
+      select("post", "category", %w( abe <mus> hest ), selected: "abe")
     )
   end
 
@@ -833,14 +868,14 @@ class FormOptionsHelperTest < ActionView::TestCase
 
     assert_dom_equal(
       expected,
-      select("album[]", "genre", %w[rap rock country], {}, { :index => nil })
+      select("album[]", "genre", %w[rap rock country], {}, { index: nil })
     )
   end
 
   def test_select_escapes_options
     assert_dom_equal(
       '<select id="post_title" name="post[title]">&lt;script&gt;alert(1)&lt;/script&gt;</select>',
-      select('post', 'title', '<script>alert(1)</script>')
+      select("post", "title", "<script>alert(1)</script>")
     )
   end
 
@@ -849,7 +884,7 @@ class FormOptionsHelperTest < ActionView::TestCase
     @post.category = "<mus>"
     assert_dom_equal(
       "<select id=\"post_category\" name=\"post[category]\"><option value=\"abe\">abe</option>\n<option value=\"&lt;mus&gt;\">&lt;mus&gt;</option>\n<option value=\"hest\">hest</option></select>",
-      select("post", "category", %w( abe <mus> hest ), :selected => nil)
+      select("post", "category", %w( abe <mus> hest ), selected: nil)
     )
   end
 
@@ -858,7 +893,7 @@ class FormOptionsHelperTest < ActionView::TestCase
     @post.category = "<mus>"
     assert_dom_equal(
       "<select id=\"post_category\" name=\"post[category]\"><option value=\"abe\">abe</option>\n<option value=\"&lt;mus&gt;\" selected=\"selected\">&lt;mus&gt;</option>\n<option value=\"hest\" disabled=\"disabled\">hest</option></select>",
-      select("post", "category", %w( abe <mus> hest ), :disabled => 'hest')
+      select("post", "category", %w( abe <mus> hest ), disabled: "hest")
     )
   end
 
@@ -866,7 +901,7 @@ class FormOptionsHelperTest < ActionView::TestCase
     @post = Post.new
     assert_dom_equal(
       "<select id=\"post_locale\" name=\"post[locale]\"><option value=\"en\">en</option>\n<option value=\"ru\" selected=\"selected\">ru</option></select>",
-      select("post", "locale", %w( en ru ), :selected => 'ru')
+      select("post", "locale", %w( en ru ), selected: "ru")
     )
   end
 
@@ -874,7 +909,7 @@ class FormOptionsHelperTest < ActionView::TestCase
     @post = Post.new
     assert_dom_equal(
       "<select id=\"post_category\" name=\"post[category]\"><option value=\"one\">one</option>\n<option selected=\"selected\" value=\"two\">two</option></select>",
-      select("post", "category", %w( one two ), :selected => 'two', :prompt => true)
+      select("post", "category", %w( one two ), selected: "two", prompt: true)
     )
   end
 
@@ -883,7 +918,7 @@ class FormOptionsHelperTest < ActionView::TestCase
     @post.category = "<mus>"
     assert_dom_equal(
       "<select id=\"post_category\" name=\"post[category]\"><option value=\"abe\" disabled=\"disabled\">abe</option>\n<option value=\"&lt;mus&gt;\" selected=\"selected\">&lt;mus&gt;</option>\n<option value=\"hest\" disabled=\"disabled\">hest</option></select>",
-      select("post", "category", %w( abe <mus> hest ), :disabled => ['hest', 'abe'])
+      select("post", "category", %w( abe <mus> hest ), disabled: ["hest", "abe"])
     )
   end
 
@@ -896,6 +931,14 @@ class FormOptionsHelperTest < ActionView::TestCase
     )
   end
 
+  def test_select_with_enumerable
+    @post = Post.new
+    assert_dom_equal(
+      "<select id=\"post_category\" name=\"post[category]\"><option value=\"one\">one</option>\n<option value=\"two\">two</option></select>",
+      select("post", "category", CustomEnumerable.new)
+    )
+  end
+
   def test_collection_select
     @post = Post.new
     @post.author_name = "Babe"
@@ -924,7 +967,7 @@ class FormOptionsHelperTest < ActionView::TestCase
     @post = Post.new
     @post.author_name = "Babe"
 
-    output_buffer = fields_for :post, @post, :index => 815 do |f|
+    output_buffer = fields_for :post, @post, index: 815 do |f|
       concat f.collection_select(:author_name, dummy_posts, :author_name, :author_name)
     end
 
@@ -955,7 +998,7 @@ class FormOptionsHelperTest < ActionView::TestCase
 
     assert_dom_equal(
       "<select id=\"post_author_name\" name=\"post[author_name]\" style=\"width: 200px\"><option value=\"\"></option>\n<option value=\"&lt;Abe&gt;\">&lt;Abe&gt;</option>\n<option value=\"Babe\" selected=\"selected\">Babe</option>\n<option value=\"Cabe\">Cabe</option></select>",
-      collection_select("post", "author_name", dummy_posts, "author_name", "author_name", { :include_blank => true }, "style" => "width: 200px")
+      collection_select("post", "author_name", dummy_posts, "author_name", "author_name", { include_blank: true }, { "style" => "width: 200px" })
     )
   end
 
@@ -965,7 +1008,7 @@ class FormOptionsHelperTest < ActionView::TestCase
 
     assert_dom_equal(
       "<select id=\"post_author_name\" name=\"post[author_name]\" style=\"width: 200px\"><option value=\"\">No Selection</option>\n<option value=\"&lt;Abe&gt;\">&lt;Abe&gt;</option>\n<option value=\"Babe\" selected=\"selected\">Babe</option>\n<option value=\"Cabe\">Cabe</option></select>",
-      collection_select("post", "author_name", dummy_posts, "author_name", "author_name", { :include_blank => 'No Selection' }, "style" => "width: 200px")
+      collection_select("post", "author_name", dummy_posts, "author_name", "author_name", { include_blank: "No Selection" }, { "style" => "width: 200px" })
     )
   end
 
@@ -976,10 +1019,10 @@ class FormOptionsHelperTest < ActionView::TestCase
     expected = "<input type=\"hidden\" name=\"post[author_name][]\" value=\"\"/><select id=\"post_author_name\" name=\"post[author_name][]\" multiple=\"multiple\"><option value=\"\"></option>\n<option value=\"&lt;Abe&gt;\">&lt;Abe&gt;</option>\n<option value=\"Babe\" selected=\"selected\">Babe</option>\n<option value=\"Cabe\">Cabe</option></select>"
 
     # Should suffix default name with [].
-    assert_dom_equal expected, collection_select("post", "author_name", dummy_posts, "author_name", "author_name", { :include_blank => true }, :multiple => true)
+    assert_dom_equal expected, collection_select("post", "author_name", dummy_posts, "author_name", "author_name", { include_blank: true }, { multiple: true })
 
     # Shouldn't suffix custom name with [].
-    assert_dom_equal expected, collection_select("post", "author_name", dummy_posts, "author_name", "author_name", { :include_blank => true, :name => 'post[author_name][]' }, :multiple => true)
+    assert_dom_equal expected, collection_select("post", "author_name", dummy_posts, "author_name", "author_name", { include_blank: true, name: "post[author_name][]" }, { multiple: true })
   end
 
   def test_collection_select_with_blank_and_selected
@@ -988,7 +1031,7 @@ class FormOptionsHelperTest < ActionView::TestCase
 
     assert_dom_equal(
       %{<select id="post_author_name" name="post[author_name]"><option value=""></option>\n<option value="&lt;Abe&gt;" selected="selected">&lt;Abe&gt;</option>\n<option value="Babe">Babe</option>\n<option value="Cabe">Cabe</option></select>},
-      collection_select("post", "author_name", dummy_posts, "author_name", "author_name", {:include_blank => true, :selected => "<Abe>"})
+      collection_select("post", "author_name", dummy_posts, "author_name", "author_name", include_blank: true, selected: "<Abe>")
     )
   end
 
@@ -998,7 +1041,7 @@ class FormOptionsHelperTest < ActionView::TestCase
 
     assert_dom_equal(
       "<select id=\"post_author_name\" name=\"post[author_name]\"><option value=\"&lt;Abe&gt;\">&lt;Abe&gt;</option>\n<option value=\"Babe\" selected=\"selected\">Babe</option>\n<option value=\"Cabe\" disabled=\"disabled\">Cabe</option></select>",
-      collection_select("post", "author_name", dummy_posts, "author_name", "author_name", :disabled => 'Cabe')
+      collection_select("post", "author_name", dummy_posts, "author_name", "author_name", disabled: "Cabe")
     )
   end
 
@@ -1022,13 +1065,13 @@ class FormOptionsHelperTest < ActionView::TestCase
 
   def test_time_zone_select
     @firm = Firm.new("D")
-    html = time_zone_select( "firm", "time_zone" )
-    assert_dom_equal "<select id=\"firm_time_zone\" name=\"firm[time_zone]\">" +
-                 "<option value=\"A\">A</option>\n" +
-                 "<option value=\"B\">B</option>\n" +
-                 "<option value=\"C\">C</option>\n" +
-                 "<option value=\"D\" selected=\"selected\">D</option>\n" +
-                 "<option value=\"E\">E</option>" +
+    html = time_zone_select("firm", "time_zone")
+    assert_dom_equal "<select id=\"firm_time_zone\" name=\"firm[time_zone]\">" \
+                 "<option value=\"A\">A</option>\n" \
+                 "<option value=\"B\">B</option>\n" \
+                 "<option value=\"C\">C</option>\n" \
+                 "<option value=\"D\" selected=\"selected\">D</option>\n" \
+                 "<option value=\"E\">E</option>" \
                  "</select>",
                  html
   end
@@ -1041,12 +1084,12 @@ class FormOptionsHelperTest < ActionView::TestCase
     end
 
     assert_dom_equal(
-      "<select id=\"firm_time_zone\" name=\"firm[time_zone]\">" +
-      "<option value=\"A\">A</option>\n" +
-      "<option value=\"B\">B</option>\n" +
-      "<option value=\"C\">C</option>\n" +
-      "<option value=\"D\" selected=\"selected\">D</option>\n" +
-      "<option value=\"E\">E</option>" +
+      "<select id=\"firm_time_zone\" name=\"firm[time_zone]\">" \
+      "<option value=\"A\">A</option>\n" \
+      "<option value=\"B\">B</option>\n" \
+      "<option value=\"C\">C</option>\n" \
+      "<option value=\"D\" selected=\"selected\">D</option>\n" \
+      "<option value=\"E\">E</option>" \
       "</select>",
       output_buffer
     )
@@ -1055,17 +1098,17 @@ class FormOptionsHelperTest < ActionView::TestCase
   def test_time_zone_select_under_fields_for_with_index
     @firm = Firm.new("D")
 
-    output_buffer = fields_for :firm, @firm, :index => 305 do |f|
+    output_buffer = fields_for :firm, @firm, index: 305 do |f|
       concat f.time_zone_select(:time_zone)
     end
 
     assert_dom_equal(
-      "<select id=\"firm_305_time_zone\" name=\"firm[305][time_zone]\">" +
-      "<option value=\"A\">A</option>\n" +
-      "<option value=\"B\">B</option>\n" +
-      "<option value=\"C\">C</option>\n" +
-      "<option value=\"D\" selected=\"selected\">D</option>\n" +
-      "<option value=\"E\">E</option>" +
+      "<select id=\"firm_305_time_zone\" name=\"firm[305][time_zone]\">" \
+      "<option value=\"A\">A</option>\n" \
+      "<option value=\"B\">B</option>\n" \
+      "<option value=\"C\">C</option>\n" \
+      "<option value=\"D\" selected=\"selected\">D</option>\n" \
+      "<option value=\"E\">E</option>" \
       "</select>",
       output_buffer
     )
@@ -1080,12 +1123,12 @@ class FormOptionsHelperTest < ActionView::TestCase
     end
 
     assert_dom_equal(
-      "<select id=\"firm_305_time_zone\" name=\"firm[305][time_zone]\">" +
-      "<option value=\"A\">A</option>\n" +
-      "<option value=\"B\">B</option>\n" +
-      "<option value=\"C\">C</option>\n" +
-      "<option value=\"D\" selected=\"selected\">D</option>\n" +
-      "<option value=\"E\">E</option>" +
+      "<select id=\"firm_305_time_zone\" name=\"firm[305][time_zone]\">" \
+      "<option value=\"A\">A</option>\n" \
+      "<option value=\"B\">B</option>\n" \
+      "<option value=\"C\">C</option>\n" \
+      "<option value=\"D\" selected=\"selected\">D</option>\n" \
+      "<option value=\"E\">E</option>" \
       "</select>",
       output_buffer
     )
@@ -1093,28 +1136,28 @@ class FormOptionsHelperTest < ActionView::TestCase
 
   def test_time_zone_select_with_blank
     @firm = Firm.new("D")
-    html = time_zone_select("firm", "time_zone", nil, :include_blank => true)
-    assert_dom_equal "<select id=\"firm_time_zone\" name=\"firm[time_zone]\">" +
-                 "<option value=\"\"></option>\n" +
-                 "<option value=\"A\">A</option>\n" +
-                 "<option value=\"B\">B</option>\n" +
-                 "<option value=\"C\">C</option>\n" +
-                 "<option value=\"D\" selected=\"selected\">D</option>\n" +
-                 "<option value=\"E\">E</option>" +
+    html = time_zone_select("firm", "time_zone", nil, include_blank: true)
+    assert_dom_equal "<select id=\"firm_time_zone\" name=\"firm[time_zone]\">" \
+                 "<option value=\"\"></option>\n" \
+                 "<option value=\"A\">A</option>\n" \
+                 "<option value=\"B\">B</option>\n" \
+                 "<option value=\"C\">C</option>\n" \
+                 "<option value=\"D\" selected=\"selected\">D</option>\n" \
+                 "<option value=\"E\">E</option>" \
                  "</select>",
                  html
   end
 
   def test_time_zone_select_with_blank_as_string
     @firm = Firm.new("D")
-    html = time_zone_select("firm", "time_zone", nil, :include_blank => 'No Zone')
-    assert_dom_equal "<select id=\"firm_time_zone\" name=\"firm[time_zone]\">" +
-                 "<option value=\"\">No Zone</option>\n" +
-                 "<option value=\"A\">A</option>\n" +
-                 "<option value=\"B\">B</option>\n" +
-                 "<option value=\"C\">C</option>\n" +
-                 "<option value=\"D\" selected=\"selected\">D</option>\n" +
-                 "<option value=\"E\">E</option>" +
+    html = time_zone_select("firm", "time_zone", nil, include_blank: "No Zone")
+    assert_dom_equal "<select id=\"firm_time_zone\" name=\"firm[time_zone]\">" \
+                 "<option value=\"\">No Zone</option>\n" \
+                 "<option value=\"A\">A</option>\n" \
+                 "<option value=\"B\">B</option>\n" \
+                 "<option value=\"C\">C</option>\n" \
+                 "<option value=\"D\" selected=\"selected\">D</option>\n" \
+                 "<option value=\"E\">E</option>" \
                  "</select>",
                  html
   end
@@ -1122,64 +1165,64 @@ class FormOptionsHelperTest < ActionView::TestCase
   def test_time_zone_select_with_style
     @firm = Firm.new("D")
     html = time_zone_select("firm", "time_zone", nil, {},
-      "style" => "color: red")
-    assert_dom_equal "<select id=\"firm_time_zone\" name=\"firm[time_zone]\" style=\"color: red\">" +
-                 "<option value=\"A\">A</option>\n" +
-                 "<option value=\"B\">B</option>\n" +
-                 "<option value=\"C\">C</option>\n" +
-                 "<option value=\"D\" selected=\"selected\">D</option>\n" +
-                 "<option value=\"E\">E</option>" +
+      { "style" => "color: red" })
+    assert_dom_equal "<select id=\"firm_time_zone\" name=\"firm[time_zone]\" style=\"color: red\">" \
+                 "<option value=\"A\">A</option>\n" \
+                 "<option value=\"B\">B</option>\n" \
+                 "<option value=\"C\">C</option>\n" \
+                 "<option value=\"D\" selected=\"selected\">D</option>\n" \
+                 "<option value=\"E\">E</option>" \
                  "</select>",
                  html
     assert_dom_equal html, time_zone_select("firm", "time_zone", nil, {},
-      :style => "color: red")
+      { style: "color: red" })
   end
 
   def test_time_zone_select_with_blank_and_style
     @firm = Firm.new("D")
     html = time_zone_select("firm", "time_zone", nil,
-      { :include_blank => true }, "style" => "color: red")
-    assert_dom_equal "<select id=\"firm_time_zone\" name=\"firm[time_zone]\" style=\"color: red\">" +
-                 "<option value=\"\"></option>\n" +
-                 "<option value=\"A\">A</option>\n" +
-                 "<option value=\"B\">B</option>\n" +
-                 "<option value=\"C\">C</option>\n" +
-                 "<option value=\"D\" selected=\"selected\">D</option>\n" +
-                 "<option value=\"E\">E</option>" +
+      { include_blank: true }, { "style" => "color: red" })
+    assert_dom_equal "<select id=\"firm_time_zone\" name=\"firm[time_zone]\" style=\"color: red\">" \
+                 "<option value=\"\"></option>\n" \
+                 "<option value=\"A\">A</option>\n" \
+                 "<option value=\"B\">B</option>\n" \
+                 "<option value=\"C\">C</option>\n" \
+                 "<option value=\"D\" selected=\"selected\">D</option>\n" \
+                 "<option value=\"E\">E</option>" \
                  "</select>",
                  html
     assert_dom_equal html, time_zone_select("firm", "time_zone", nil,
-      { :include_blank => true }, :style => "color: red")
+      { include_blank: true }, { style: "color: red" })
   end
 
   def test_time_zone_select_with_blank_as_string_and_style
     @firm = Firm.new("D")
     html = time_zone_select("firm", "time_zone", nil,
-      { :include_blank => 'No Zone' }, "style" => "color: red")
-    assert_dom_equal "<select id=\"firm_time_zone\" name=\"firm[time_zone]\" style=\"color: red\">" +
-                 "<option value=\"\">No Zone</option>\n" +
-                 "<option value=\"A\">A</option>\n" +
-                 "<option value=\"B\">B</option>\n" +
-                 "<option value=\"C\">C</option>\n" +
-                 "<option value=\"D\" selected=\"selected\">D</option>\n" +
-                 "<option value=\"E\">E</option>" +
+      { include_blank: "No Zone" }, { "style" => "color: red" })
+    assert_dom_equal "<select id=\"firm_time_zone\" name=\"firm[time_zone]\" style=\"color: red\">" \
+                 "<option value=\"\">No Zone</option>\n" \
+                 "<option value=\"A\">A</option>\n" \
+                 "<option value=\"B\">B</option>\n" \
+                 "<option value=\"C\">C</option>\n" \
+                 "<option value=\"D\" selected=\"selected\">D</option>\n" \
+                 "<option value=\"E\">E</option>" \
                  "</select>",
                  html
     assert_dom_equal html, time_zone_select("firm", "time_zone", nil,
-      { :include_blank => 'No Zone' }, :style => "color: red")
+      { include_blank: "No Zone" }, { style: "color: red" })
   end
 
   def test_time_zone_select_with_priority_zones
     @firm = Firm.new("D")
     zones = [ ActiveSupport::TimeZone.new("A"), ActiveSupport::TimeZone.new("D") ]
-    html = time_zone_select("firm", "time_zone", zones )
-    assert_dom_equal "<select id=\"firm_time_zone\" name=\"firm[time_zone]\">" +
-                 "<option value=\"A\">A</option>\n" +
-                 "<option value=\"D\" selected=\"selected\">D</option>" +
-                 "<option value=\"\" disabled=\"disabled\">-------------</option>\n" +
-                 "<option value=\"B\">B</option>\n" +
-                 "<option value=\"C\">C</option>\n" +
-                 "<option value=\"E\">E</option>" +
+    html = time_zone_select("firm", "time_zone", zones)
+    assert_dom_equal "<select id=\"firm_time_zone\" name=\"firm[time_zone]\">" \
+                 "<option value=\"A\">A</option>\n" \
+                 "<option value=\"D\" selected=\"selected\">D</option>" \
+                 "<option value=\"\" disabled=\"disabled\">-------------</option>\n" \
+                 "<option value=\"B\">B</option>\n" \
+                 "<option value=\"C\">C</option>\n" \
+                 "<option value=\"E\">E</option>" \
                  "</select>",
                  html
   end
@@ -1192,13 +1235,13 @@ class FormOptionsHelperTest < ActionView::TestCase
     end
 
     html = time_zone_select("firm", "time_zone", /A|D/)
-    assert_dom_equal "<select id=\"firm_time_zone\" name=\"firm[time_zone]\">" +
-                 "<option value=\"A\">A</option>\n" +
-                 "<option value=\"D\" selected=\"selected\">D</option>" +
-                 "<option value=\"\" disabled=\"disabled\">-------------</option>\n" +
-                 "<option value=\"B\">B</option>\n" +
-                 "<option value=\"C\">C</option>\n" +
-                 "<option value=\"E\">E</option>" +
+    assert_dom_equal "<select id=\"firm_time_zone\" name=\"firm[time_zone]\">" \
+                 "<option value=\"A\">A</option>\n" \
+                 "<option value=\"D\" selected=\"selected\">D</option>" \
+                 "<option value=\"\" disabled=\"disabled\">-------------</option>\n" \
+                 "<option value=\"B\">B</option>\n" \
+                 "<option value=\"C\">C</option>\n" \
+                 "<option value=\"E\">E</option>" \
                  "</select>",
                  html
   end
@@ -1213,42 +1256,61 @@ class FormOptionsHelperTest < ActionView::TestCase
     end
 
     html = time_zone_select("firm", "time_zone", /A|D/)
-    assert_dom_equal "<select id=\"firm_time_zone\" name=\"firm[time_zone]\">" +
-                 "<option value=\"\" disabled=\"disabled\">-------------</option>\n" +
-                 "<option value=\"A\">A</option>\n" +
-                 "<option value=\"B\">B</option>\n" +
-                 "<option value=\"C\">C</option>\n" +
-                 "<option value=\"D\" selected=\"selected\">D</option>\n" +
-                 "<option value=\"E\">E</option>" +
+    assert_dom_equal "<select id=\"firm_time_zone\" name=\"firm[time_zone]\">" \
+                 "<option value=\"\" disabled=\"disabled\">-------------</option>\n" \
+                 "<option value=\"A\">A</option>\n" \
+                 "<option value=\"B\">B</option>\n" \
+                 "<option value=\"C\">C</option>\n" \
+                 "<option value=\"D\" selected=\"selected\">D</option>\n" \
+                 "<option value=\"E\">E</option>" \
                  "</select>",
                  html
   end
 
-  def test_time_zone_select_with_default_time_zone_and_nil_value
-     @firm = Firm.new()
-     @firm.time_zone = nil
+  def test_time_zone_select_with_priority_zones_and_errors
+    @firm = Firm.new("D")
+    @firm.extend ActiveModel::Validations
+    @firm.errors[:time_zone] << "invalid"
+    zones = [ ActiveSupport::TimeZone.new("A"), ActiveSupport::TimeZone.new("D") ]
+    html = time_zone_select("firm", "time_zone", zones)
+    assert_dom_equal "<div class=\"field_with_errors\">" \
+                 "<select id=\"firm_time_zone\" name=\"firm[time_zone]\">" \
+                 "<option value=\"A\">A</option>\n" \
+                 "<option value=\"D\" selected=\"selected\">D</option>" \
+                 "<option value=\"\" disabled=\"disabled\">-------------</option>\n" \
+                 "<option value=\"B\">B</option>\n" \
+                 "<option value=\"C\">C</option>\n" \
+                 "<option value=\"E\">E</option>" \
+                 "</select>" \
+                 "</div>",
+                 html
+  end
 
-     html = time_zone_select( "firm", "time_zone", nil, :default => 'B' )
-     assert_dom_equal "<select id=\"firm_time_zone\" name=\"firm[time_zone]\">" +
-                   "<option value=\"A\">A</option>\n" +
-                   "<option value=\"B\" selected=\"selected\">B</option>\n" +
-                   "<option value=\"C\">C</option>\n" +
-                   "<option value=\"D\">D</option>\n" +
-                   "<option value=\"E\">E</option>" +
-                   "</select>",
-                   html
+  def test_time_zone_select_with_default_time_zone_and_nil_value
+    @firm = Firm.new()
+    @firm.time_zone = nil
+
+    html = time_zone_select("firm", "time_zone", nil, default: "B")
+    assert_dom_equal "<select id=\"firm_time_zone\" name=\"firm[time_zone]\">" \
+                  "<option value=\"A\">A</option>\n" \
+                  "<option value=\"B\" selected=\"selected\">B</option>\n" \
+                  "<option value=\"C\">C</option>\n" \
+                  "<option value=\"D\">D</option>\n" \
+                  "<option value=\"E\">E</option>" \
+                  "</select>",
+                  html
   end
 
   def test_time_zone_select_with_default_time_zone_and_value
-    @firm = Firm.new('D')
-
-    html = time_zone_select( "firm", "time_zone", nil, :default => 'B' )
-    assert_dom_equal "<select id=\"firm_time_zone\" name=\"firm[time_zone]\">" +
-                  "<option value=\"A\">A</option>\n" +
-                  "<option value=\"B\">B</option>\n" +
-                  "<option value=\"C\">C</option>\n" +
-                  "<option value=\"D\" selected=\"selected\">D</option>\n" +
-                  "<option value=\"E\">E</option>" +
+    @firm = Firm.new("D")
+
+    html = time_zone_select("firm", "time_zone", nil, default: "B")
+    assert_dom_equal "<select id=\"firm_time_zone\" name=\"firm[time_zone]\">" \
+                  "<option value=\"A\">A</option>\n" \
+                  "<option value=\"B\">B</option>\n" \
+                  "<option value=\"C\">C</option>\n" \
+                  "<option value=\"D\" selected=\"selected\">D</option>\n" \
+                  "<option value=\"E\">E</option>" \
                   "</select>",
                   html
   end
@@ -1256,86 +1318,86 @@ class FormOptionsHelperTest < ActionView::TestCase
   def test_options_for_select_with_element_attributes
     assert_dom_equal(
       "<option value=\"&lt;Denmark&gt;\" class=\"bold\">&lt;Denmark&gt;</option>\n<option value=\"USA\" onclick=\"alert(&#39;Hello World&#39;);\">USA</option>\n<option value=\"Sweden\">Sweden</option>\n<option value=\"Germany\">Germany</option>",
-      options_for_select([ [ "<Denmark>", { :class => 'bold' } ], [ "USA", { :onclick => "alert('Hello World');" } ], [ "Sweden" ], "Germany" ])
+      options_for_select([ [ "<Denmark>", { class: "bold" } ], [ "USA", { onclick: "alert('Hello World');" } ], [ "Sweden" ], "Germany" ])
     )
   end
 
   def test_options_for_select_with_data_element
     assert_dom_equal(
       "<option value=\"&lt;Denmark&gt;\" data-test=\"bold\">&lt;Denmark&gt;</option>",
-      options_for_select([ [ "<Denmark>", { :data => { :test => 'bold' } } ] ])
+      options_for_select([ [ "<Denmark>", { data: { test: "bold" } } ] ])
     )
   end
 
   def test_options_for_select_with_data_element_with_special_characters
     assert_dom_equal(
       "<option value=\"&lt;Denmark&gt;\" data-test=\"&lt;bold&gt;\">&lt;Denmark&gt;</option>",
-      options_for_select([ [ "<Denmark>", { :data => { :test => '<bold>' } } ] ])
+      options_for_select([ [ "<Denmark>", { data: { test: "<bold>" } } ] ])
     )
   end
 
   def test_options_for_select_with_element_attributes_and_selection
     assert_dom_equal(
       "<option value=\"&lt;Denmark&gt;\">&lt;Denmark&gt;</option>\n<option value=\"USA\" class=\"bold\" selected=\"selected\">USA</option>\n<option value=\"Sweden\">Sweden</option>",
-      options_for_select([ "<Denmark>", [ "USA", { :class => 'bold' } ], "Sweden" ], "USA")
+      options_for_select([ "<Denmark>", [ "USA", { class: "bold" } ], "Sweden" ], "USA")
     )
   end
 
   def test_options_for_select_with_element_attributes_and_selection_array
     assert_dom_equal(
       "<option value=\"&lt;Denmark&gt;\">&lt;Denmark&gt;</option>\n<option value=\"USA\" class=\"bold\" selected=\"selected\">USA</option>\n<option value=\"Sweden\" selected=\"selected\">Sweden</option>",
-      options_for_select([ "<Denmark>", [ "USA", { :class => 'bold' } ], "Sweden" ], [ "USA", "Sweden" ])
+      options_for_select([ "<Denmark>", [ "USA", { class: "bold" } ], "Sweden" ], [ "USA", "Sweden" ])
     )
   end
 
   def test_options_for_select_with_special_characters
     assert_dom_equal(
       "<option value=\"&lt;Denmark&gt;\" onclick=\"alert(&quot;&lt;code&gt;&quot;)\">&lt;Denmark&gt;</option>",
-      options_for_select([ [ "<Denmark>", { :onclick => %(alert("<code>")) } ] ])
+      options_for_select([ [ "<Denmark>", { onclick: %(alert("<code>")) } ] ])
     )
   end
 
   def test_option_html_attributes_with_no_array_element
-    assert_equal({}, option_html_attributes('foo'))
+    assert_equal({}, option_html_attributes("foo"))
   end
 
   def test_option_html_attributes_without_hash
-    assert_equal({}, option_html_attributes([ 'foo', 'bar' ]))
+    assert_equal({}, option_html_attributes([ "foo", "bar" ]))
   end
 
   def test_option_html_attributes_with_single_element_hash
     assert_equal(
-      {:class => 'fancy'},
-      option_html_attributes([ 'foo', 'bar', { :class => 'fancy' } ])
+      { class: "fancy" },
+      option_html_attributes([ "foo", "bar", { class: "fancy" } ])
     )
   end
 
   def test_option_html_attributes_with_multiple_element_hash
     assert_equal(
-      {:class => 'fancy', 'onclick' => "alert('Hello World');"},
-      option_html_attributes([ 'foo', 'bar', { :class => 'fancy', 'onclick' => "alert('Hello World');" } ])
+      { :class => "fancy", "onclick" => "alert('Hello World');" },
+      option_html_attributes([ "foo", "bar", { :class => "fancy", "onclick" => "alert('Hello World');" } ])
     )
   end
 
   def test_option_html_attributes_with_multiple_hashes
     assert_equal(
-      {:class => 'fancy', 'onclick' => "alert('Hello World');"},
-      option_html_attributes([ 'foo', 'bar', { :class => 'fancy' }, { 'onclick' => "alert('Hello World');" } ])
+      { :class => "fancy", "onclick" => "alert('Hello World');" },
+      option_html_attributes([ "foo", "bar", { class: "fancy" }, { "onclick" => "alert('Hello World');" } ])
     )
   end
 
   def test_option_html_attributes_with_multiple_hashes_does_not_modify_them
-    options1 = { class: 'fancy' }
+    options1 = { class: "fancy" }
     options2 = { onclick: "alert('Hello World');" }
-    option_html_attributes([ 'foo', 'bar', options1, options2 ])
+    option_html_attributes([ "foo", "bar", options1, options2 ])
 
-    assert_equal({ class: 'fancy' }, options1)
+    assert_equal({ class: "fancy" }, options1)
     assert_equal({ onclick: "alert('Hello World');" }, options2)
   end
 
   def test_grouped_collection_select
     @post = Post.new
-    @post.origin = 'dk'
+    @post.origin = "dk"
 
     assert_dom_equal(
       %Q{<select id="post_origin" name="post[origin]"><optgroup label="&lt;Africa&gt;"><option value="&lt;sa&gt;">&lt;South Africa&gt;</option>\n<option value="so">Somalia</option></optgroup><optgroup label="Europe"><option value="dk" selected="selected">Denmark</option>\n<option value="ie">Ireland</option></optgroup></select>},
@@ -1348,7 +1410,7 @@ class FormOptionsHelperTest < ActionView::TestCase
 
     assert_dom_equal(
       %Q{<select id="post_origin" name="post[origin]"><optgroup label="&lt;Africa&gt;"><option value="&lt;sa&gt;">&lt;South Africa&gt;</option>\n<option value="so">Somalia</option></optgroup><optgroup label="Europe"><option value="dk" selected="selected">Denmark</option>\n<option value="ie">Ireland</option></optgroup></select>},
-      grouped_collection_select("post", "origin", dummy_continents, :countries, :continent_name, :country_id, :country_name, :selected => 'dk')
+      grouped_collection_select("post", "origin", dummy_continents, :countries, :continent_name, :country_id, :country_name, selected: "dk")
     )
   end
 
@@ -1357,13 +1419,13 @@ class FormOptionsHelperTest < ActionView::TestCase
 
     assert_dom_equal(
       %Q{<select id="post_origin" name="post[origin]"><optgroup label="&lt;Africa&gt;"><option value="&lt;sa&gt;">&lt;South Africa&gt;</option>\n<option value="so">Somalia</option></optgroup><optgroup label="Europe"><option disabled="disabled" value="dk">Denmark</option>\n<option value="ie">Ireland</option></optgroup></select>},
-      grouped_collection_select("post", "origin", dummy_continents, :countries, :continent_name, :country_id, :country_name, :disabled => 'dk')
+      grouped_collection_select("post", "origin", dummy_continents, :countries, :continent_name, :country_id, :country_name, disabled: "dk")
     )
   end
 
   def test_grouped_collection_select_under_fields_for
     @post = Post.new
-    @post.origin = 'dk'
+    @post.origin = "dk"
 
     output_buffer = fields_for :post, @post do |f|
       concat f.grouped_collection_select("origin", dummy_continents, :countries, :continent_name, :country_id, :country_name)
@@ -1377,14 +1439,14 @@ class FormOptionsHelperTest < ActionView::TestCase
 
   private
 
-  def dummy_posts
-    [ Post.new("<Abe> went home", "<Abe>", "To a little house", "shh!"),
-      Post.new("Babe went home", "Babe", "To a little house", "shh!"),
-      Post.new("Cabe went home", "Cabe", "To a little house", "shh!") ]
-  end
+    def dummy_posts
+      [ Post.new("<Abe> went home", "<Abe>", "To a little house", "shh!"),
+        Post.new("Babe went home", "Babe", "To a little house", "shh!"),
+        Post.new("Cabe went home", "Cabe", "To a little house", "shh!") ]
+    end
 
-  def dummy_continents
-    [ Continent.new("<Africa>", [Country.new("<sa>", "<South Africa>"), Country.new("so", "Somalia")]),
-      Continent.new("Europe", [Country.new("dk", "Denmark"), Country.new("ie", "Ireland")]) ]
-  end
+    def dummy_continents
+      [ Continent.new("<Africa>", [Country.new("<sa>", "<South Africa>"), Country.new("so", "Somalia")]),
+        Continent.new("Europe", [Country.new("dk", "Denmark"), Country.new("ie", "Ireland")]) ]
+    end
 end
diff --git a/actionview/test/template/form_tag_helper_test.rb b/actionview/test/template/form_tag_helper_test.rb
index 5b0b708618..5e328ebf53 100644
--- a/actionview/test/template/form_tag_helper_test.rb
+++ b/actionview/test/template/form_tag_helper_test.rb
@@ -1,10 +1,22 @@
-require 'abstract_unit'
+# frozen_string_literal: true
+
+require "abstract_unit"
 
 class FormTagHelperTest < ActionView::TestCase
   include RenderERBUtils
 
   tests ActionView::Helpers::FormTagHelper
 
+  class WithActiveStorageRoutesControllers < ActionController::Base
+    test_routes do
+      post "/rails/active_storage/direct_uploads" => "active_storage/direct_uploads#create", as: :rails_direct_uploads
+    end
+
+    def url_options
+      { host: "testtwo.host" }
+    end
+  end
+
   def setup
     super
     @controller = BasicController.new
@@ -14,7 +26,7 @@ class FormTagHelperTest < ActionView::TestCase
     method = options[:method]
     enforce_utf8 = options.fetch(:enforce_utf8, true)
 
-    ''.tap do |txt|
+    "".dup.tap do |txt|
       if enforce_utf8
         txt << %{<input name="utf8" type="hidden" value="&#x2713;" />}
       end
@@ -30,7 +42,7 @@ class FormTagHelperTest < ActionView::TestCase
 
     method = method.to_s == "get" ? "get" : "post"
 
-    txt =  %{<form accept-charset="UTF-8" action="#{action}"}
+    txt =  %{<form accept-charset="UTF-8" action="#{action}"}.dup
     txt << %{ enctype="multipart/form-data"} if enctype
     txt << %{ data-remote="true"} if remote
     txt << %{ class="#{html_class}"} if html_class
@@ -65,20 +77,20 @@ class FormTagHelperTest < ActionView::TestCase
   end
 
   def test_check_box_tag_disabled
-    actual = check_box_tag "admin","1", false, disabled: true
+    actual = check_box_tag "admin", "1", false, disabled: true
     expected = %(<input id="admin" disabled="disabled" name="admin" type="checkbox" value="1" />)
     assert_dom_equal expected, actual
   end
 
   def test_check_box_tag_default_checked
-    actual = check_box_tag "admin","1", true
+    actual = check_box_tag "admin", "1", true
     expected = %(<input id="admin" checked="checked" name="admin" type="checkbox" value="1" />)
     assert_dom_equal expected, actual
   end
 
   def test_check_box_tag_id_sanitized
     label_elem = root_elem(check_box_tag("project[2][admin]"))
-    assert_match VALID_HTML_ID, label_elem['id']
+    assert_match VALID_HTML_ID, label_elem["id"]
   end
 
   def test_form_tag
@@ -88,54 +100,54 @@ class FormTagHelperTest < ActionView::TestCase
   end
 
   def test_form_tag_multipart
-    actual = form_tag({}, { 'multipart' => true })
-    expected = whole_form("http://www.example.com", :enctype => true)
+    actual = form_tag({}, { "multipart" => true })
+    expected = whole_form("http://www.example.com", enctype: true)
     assert_dom_equal expected, actual
   end
 
   def test_form_tag_with_method_patch
-    actual = form_tag({}, { :method => :patch })
-    expected = whole_form("http://www.example.com", :method => :patch)
+    actual = form_tag({}, { method: :patch })
+    expected = whole_form("http://www.example.com", method: :patch)
     assert_dom_equal expected, actual
   end
 
   def test_form_tag_with_method_put
-    actual = form_tag({}, { :method => :put })
-    expected = whole_form("http://www.example.com", :method => :put)
+    actual = form_tag({}, { method: :put })
+    expected = whole_form("http://www.example.com", method: :put)
     assert_dom_equal expected, actual
   end
 
   def test_form_tag_with_method_delete
-    actual = form_tag({}, { :method => :delete })
+    actual = form_tag({}, { method: :delete })
 
-    expected = whole_form("http://www.example.com", :method => :delete)
+    expected = whole_form("http://www.example.com", method: :delete)
     assert_dom_equal expected, actual
   end
 
   def test_form_tag_with_remote
-    actual = form_tag({}, :remote => true)
+    actual = form_tag({}, { remote: true })
 
-    expected = whole_form("http://www.example.com", :remote => true)
+    expected = whole_form("http://www.example.com", remote: true)
     assert_dom_equal expected, actual
   end
 
   def test_form_tag_with_remote_false
-    actual = form_tag({}, :remote => false)
+    actual = form_tag({}, { remote: false })
 
     expected = whole_form
     assert_dom_equal expected, actual
   end
 
   def test_form_tag_enforce_utf8_true
-    actual = form_tag({}, { :enforce_utf8 => true })
-    expected = whole_form("http://www.example.com", :enforce_utf8 => true)
+    actual = form_tag({}, { enforce_utf8: true })
+    expected = whole_form("http://www.example.com", enforce_utf8: true)
     assert_dom_equal expected, actual
     assert actual.html_safe?
   end
 
   def test_form_tag_enforce_utf8_false
-    actual = form_tag({}, { :enforce_utf8 => false })
-    expected = whole_form("http://www.example.com", :enforce_utf8 => false)
+    actual = form_tag({}, { enforce_utf8: false })
+    expected = whole_form("http://www.example.com", enforce_utf8: false)
     assert_dom_equal expected, actual
     assert actual.html_safe?
   end
@@ -150,7 +162,7 @@ class FormTagHelperTest < ActionView::TestCase
   def test_form_tag_with_block_and_method_in_erb
     output_buffer = render_erb("<%= form_tag('http://www.example.com', :method => :put) do %>Hello world!<% end %>")
 
-    expected = whole_form("http://www.example.com", :method => "put") do
+    expected = whole_form("http://www.example.com", method: "put") do
       "Hello world!"
     end
 
@@ -165,7 +177,7 @@ class FormTagHelperTest < ActionView::TestCase
 
   def test_hidden_field_tag_id_sanitized
     input_elem = root_elem(hidden_field_tag("item[][title]"))
-    assert_match VALID_HTML_ID, input_elem['id']
+    assert_match VALID_HTML_ID, input_elem["id"]
   end
 
   def test_file_field_tag
@@ -173,7 +185,34 @@ class FormTagHelperTest < ActionView::TestCase
   end
 
   def test_file_field_tag_with_options
-    assert_dom_equal "<input name=\"picsplz\" type=\"file\" id=\"picsplz\" class=\"pix\"/>", file_field_tag("picsplz", :class => "pix")
+    assert_dom_equal "<input name=\"picsplz\" type=\"file\" id=\"picsplz\" class=\"pix\"/>", file_field_tag("picsplz", class: "pix")
+  end
+
+  def test_file_field_tag_with_direct_upload_when_rails_direct_uploads_url_is_not_defined
+    assert_dom_equal(
+      "<input name=\"picsplz\" type=\"file\" id=\"picsplz\" class=\"pix\"/>",
+      file_field_tag("picsplz", class: "pix", direct_upload: true)
+    )
+  end
+
+  def test_file_field_tag_with_direct_upload_when_rails_direct_uploads_url_is_defined
+    @controller = WithActiveStorageRoutesControllers.new
+
+    assert_dom_equal(
+      "<input name=\"picsplz\" type=\"file\" id=\"picsplz\" class=\"pix\" data-direct-upload-url=\"http://testtwo.host/rails/active_storage/direct_uploads\"/>",
+      file_field_tag("picsplz", class: "pix", direct_upload: true)
+    )
+  end
+
+  def test_file_field_tag_with_direct_upload_dont_mutate_arguments
+    original_options = { class: "pix", direct_upload: true }
+
+    assert_dom_equal(
+      "<input name=\"picsplz\" type=\"file\" id=\"picsplz\" class=\"pix\"/>",
+      file_field_tag("picsplz", original_options)
+    )
+
+    assert_equal({ class: "pix", direct_upload: true }, original_options)
   end
 
   def test_password_field_tag
@@ -183,7 +222,7 @@ class FormTagHelperTest < ActionView::TestCase
   end
 
   def test_multiple_field_tags_with_same_options
-    options = {class: 'important'}
+    options = { class: "important" }
     assert_dom_equal %(<input name="title" type="file" id="title" class="important"/>), file_field_tag("title", options)
     assert_dom_equal %(<input type="password" name="title" id="title" value="Hello!" class="important" />), password_field_tag("title", "Hello!", options)
     assert_dom_equal %(<input type="text" name="title" id="title" value="Hello!" class="important" />), text_field_tag("title", "Hello!", options)
@@ -210,7 +249,7 @@ class FormTagHelperTest < ActionView::TestCase
     expected = %(<input id="person_gender_m" name="person[gender]" type="radio" value="m" />)
     assert_dom_equal expected, actual
 
-    actual = radio_button_tag('ctrlname', 'apache2.2')
+    actual = radio_button_tag("ctrlname", "apache2.2")
     expected = %(<input id="ctrlname_apache2.2" name="ctrlname" type="radio" value="apache2.2" />)
     assert_dom_equal expected, actual
   end
@@ -235,7 +274,7 @@ class FormTagHelperTest < ActionView::TestCase
 
   def test_select_tag_id_sanitized
     input_elem = root_elem(select_tag("project[1]people", "<option>david</option>"))
-    assert_match VALID_HTML_ID, input_elem['id']
+    assert_match VALID_HTML_ID, input_elem["id"]
   end
 
   def test_select_tag_with_include_blank
@@ -251,19 +290,19 @@ class FormTagHelperTest < ActionView::TestCase
   end
 
   def test_select_tag_with_include_blank_string
-    actual = select_tag "places", raw("<option>Home</option><option>Work</option><option>Pub</option>"), include_blank: 'Choose'
+    actual = select_tag "places", raw("<option>Home</option><option>Work</option><option>Pub</option>"), include_blank: "Choose"
     expected = %(<select id="places" name="places"><option value="">Choose</option><option>Home</option><option>Work</option><option>Pub</option></select>)
     assert_dom_equal expected, actual
   end
 
   def test_select_tag_with_prompt
-    actual = select_tag "places", raw("<option>Home</option><option>Work</option><option>Pub</option>"), :prompt => "string"
+    actual = select_tag "places", raw("<option>Home</option><option>Work</option><option>Pub</option>"), prompt: "string"
     expected = %(<select id="places" name="places"><option value="">string</option><option>Home</option><option>Work</option><option>Pub</option></select>)
     assert_dom_equal expected, actual
   end
 
   def test_select_tag_escapes_prompt
-    actual = select_tag "places", raw("<option>Home</option><option>Work</option><option>Pub</option>"), :prompt => "<script>alert(1337)</script>"
+    actual = select_tag "places", raw("<option>Home</option><option>Work</option><option>Pub</option>"), prompt: "<script>alert(1337)</script>"
     expected = %(<select id="places" name="places"><option value="">&lt;script&gt;alert(1337)&lt;/script&gt;</option><option>Home</option><option>Work</option><option>Pub</option></select>)
     assert_dom_equal expected, actual
   end
@@ -275,13 +314,13 @@ class FormTagHelperTest < ActionView::TestCase
   end
 
   def test_select_tag_with_nil_option_tags_and_include_blank
-    actual = select_tag "places", nil, :include_blank => true
+    actual = select_tag "places", nil, include_blank: true
     expected = %(<select id="places" name="places"><option value="" label=" "></option></select>)
     assert_dom_equal expected, actual
   end
 
   def test_select_tag_with_nil_option_tags_and_prompt
-    actual = select_tag "places", nil, :prompt => "string"
+    actual = select_tag "places", nil, prompt: "string"
     expected = %(<select id="places" name="places"><option value="">string</option></select>)
     assert_dom_equal expected, actual
   end
@@ -293,36 +332,36 @@ class FormTagHelperTest < ActionView::TestCase
   end
 
   def test_text_area_tag_size_symbol
-    actual = text_area_tag "body", "hello world", :size => "20x40"
+    actual = text_area_tag "body", "hello world", size: "20x40"
     expected = %(<textarea cols="20" id="body" name="body" rows="40">\nhello world</textarea>)
     assert_dom_equal expected, actual
   end
 
   def test_text_area_tag_should_disregard_size_if_its_given_as_an_integer
-    actual = text_area_tag "body", "hello world", :size => 20
+    actual = text_area_tag "body", "hello world", size: 20
     expected = %(<textarea id="body" name="body">\nhello world</textarea>)
     assert_dom_equal expected, actual
   end
 
   def test_text_area_tag_id_sanitized
     input_elem = root_elem(text_area_tag("item[][description]"))
-    assert_match VALID_HTML_ID, input_elem['id']
+    assert_match VALID_HTML_ID, input_elem["id"]
   end
 
   def test_text_area_tag_escape_content
-    actual = text_area_tag "body", "<b>hello world</b>", :size => "20x40"
+    actual = text_area_tag "body", "<b>hello world</b>", size: "20x40"
     expected = %(<textarea cols="20" id="body" name="body" rows="40">\n&lt;b&gt;hello world&lt;/b&gt;</textarea>)
     assert_dom_equal expected, actual
   end
 
   def test_text_area_tag_unescaped_content
-    actual = text_area_tag "body", "<b>hello world</b>", :size => "20x40", :escape => false
+    actual = text_area_tag "body", "<b>hello world</b>", size: "20x40", escape: false
     expected = %(<textarea cols="20" id="body" name="body" rows="40">\n<b>hello world</b></textarea>)
     assert_dom_equal expected, actual
   end
 
   def test_text_area_tag_unescaped_nil_content
-    actual = text_area_tag "body", nil, :escape => false
+    actual = text_area_tag "body", nil, escape: false
     expected = %(<textarea id="body" name="body">\n</textarea>)
     assert_dom_equal expected, actual
   end
@@ -340,11 +379,17 @@ class FormTagHelperTest < ActionView::TestCase
   end
 
   def test_text_field_tag_size_symbol
-    actual = text_field_tag "title", "Hello!", :size => 75
+    actual = text_field_tag "title", "Hello!", size: 75
     expected = %(<input id="title" name="title" size="75" type="text" value="Hello!" />)
     assert_dom_equal expected, actual
   end
 
+  def test_text_field_tag_with_ac_parameters
+    actual = text_field_tag "title", ActionController::Parameters.new(key: "value")
+    expected = %(<input id="title" name="title" type="text" value="{&quot;key&quot;=&gt;&quot;value&quot;}" />)
+    assert_dom_equal expected, actual
+  end
+
   def test_text_field_tag_size_string
     actual = text_field_tag "title", "Hello!", "size" => "75"
     expected = %(<input id="title" name="title" size="75" type="text" value="Hello!" />)
@@ -352,7 +397,7 @@ class FormTagHelperTest < ActionView::TestCase
   end
 
   def test_text_field_tag_maxlength_symbol
-    actual = text_field_tag "title", "Hello!", :maxlength => 75
+    actual = text_field_tag "title", "Hello!", maxlength: 75
     expected = %(<input id="title" name="title" maxlength="75" type="text" value="Hello!" />)
     assert_dom_equal expected, actual
   end
@@ -370,20 +415,20 @@ class FormTagHelperTest < ActionView::TestCase
   end
 
   def test_text_field_tag_with_placeholder_option
-    actual = text_field_tag "title", "Hello!", placeholder: 'Enter search term...'
+    actual = text_field_tag "title", "Hello!", placeholder: "Enter search term..."
     expected = %(<input id="title" name="title" placeholder="Enter search term..." type="text" value="Hello!" />)
     assert_dom_equal expected, actual
   end
 
   def test_text_field_tag_with_multiple_options
-    actual = text_field_tag "title", "Hello!", :size => 70, :maxlength => 80
+    actual = text_field_tag "title", "Hello!", size: 70, maxlength: 80
     expected = %(<input id="title" name="title" size="70" maxlength="80" type="text" value="Hello!" />)
     assert_dom_equal expected, actual
   end
 
   def test_text_field_tag_id_sanitized
     input_elem = root_elem(text_field_tag("item[][title]"))
-    assert_match VALID_HTML_ID, input_elem['id']
+    assert_match VALID_HTML_ID, input_elem["id"]
   end
 
   def test_label_tag_without_text
@@ -412,11 +457,11 @@ class FormTagHelperTest < ActionView::TestCase
 
   def test_label_tag_id_sanitized
     label_elem = root_elem(label_tag("item[title]"))
-    assert_match VALID_HTML_ID, label_elem['for']
+    assert_match VALID_HTML_ID, label_elem["for"]
   end
 
   def test_label_tag_with_block
-    assert_dom_equal('<label>Blocked</label>', label_tag { "Blocked" })
+    assert_dom_equal("<label>Blocked</label>", label_tag { "Blocked" })
   end
 
   def test_label_tag_with_block_and_argument
@@ -425,21 +470,21 @@ class FormTagHelperTest < ActionView::TestCase
   end
 
   def test_label_tag_with_block_and_argument_and_options
-    output = label_tag("clock", :id => "label_clock") { "Grandfather" }
+    output = label_tag("clock", id: "label_clock") { "Grandfather" }
     assert_dom_equal('<label for="clock" id="label_clock">Grandfather</label>', output)
   end
 
   def test_boolean_options
-    assert_dom_equal %(<input checked="checked" disabled="disabled" id="admin" name="admin" readonly="readonly" type="checkbox" value="1" />), check_box_tag("admin", 1, true, 'disabled' => true, :readonly => "yes")
-    assert_dom_equal %(<input checked="checked" id="admin" name="admin" type="checkbox" value="1" />), check_box_tag("admin", 1, true, :disabled => false, :readonly => nil)
-    assert_dom_equal %(<input type="checkbox" />), tag(:input, :type => "checkbox", :checked => false)
-    assert_dom_equal %(<select id="people" multiple="multiple" name="people[]"><option>david</option></select>), select_tag("people", raw("<option>david</option>"), :multiple => true)
-    assert_dom_equal %(<select id="people_" multiple="multiple" name="people[]"><option>david</option></select>), select_tag("people[]", raw("<option>david</option>"), :multiple => true)
-    assert_dom_equal %(<select id="people" name="people"><option>david</option></select>), select_tag("people", raw("<option>david</option>"), :multiple => nil)
+    assert_dom_equal %(<input checked="checked" disabled="disabled" id="admin" name="admin" readonly="readonly" type="checkbox" value="1" />), check_box_tag("admin", 1, true, "disabled" => true, :readonly => "yes")
+    assert_dom_equal %(<input checked="checked" id="admin" name="admin" type="checkbox" value="1" />), check_box_tag("admin", 1, true, disabled: false, readonly: nil)
+    assert_dom_equal %(<input type="checkbox" />), tag(:input, type: "checkbox", checked: false)
+    assert_dom_equal %(<select id="people" multiple="multiple" name="people[]"><option>david</option></select>), select_tag("people", raw("<option>david</option>"), multiple: true)
+    assert_dom_equal %(<select id="people_" multiple="multiple" name="people[]"><option>david</option></select>), select_tag("people[]", raw("<option>david</option>"), multiple: true)
+    assert_dom_equal %(<select id="people" name="people"><option>david</option></select>), select_tag("people", raw("<option>david</option>"), multiple: nil)
   end
 
   def test_stringify_symbol_keys
-    actual = text_field_tag "title", "Hello!", :id => "admin"
+    actual = text_field_tag "title", "Hello!", id: "admin"
     expected = %(<input id="admin" name="title" type="text" value="Hello!" />)
     assert_dom_equal expected, actual
   end
@@ -447,7 +492,7 @@ class FormTagHelperTest < ActionView::TestCase
   def test_submit_tag
     assert_dom_equal(
       %(<input name='commit' data-disable-with="Saving..." onclick="alert(&#39;hello!&#39;)" type="submit" value="Save" />),
-      submit_tag("Save", :onclick => "alert('hello!')", :data => { :disable_with => "Saving..." })
+      submit_tag("Save", onclick: "alert('hello!')", data: { disable_with: "Saving..." })
     )
   end
 
@@ -471,42 +516,49 @@ class FormTagHelperTest < ActionView::TestCase
   def test_submit_tag_having_data_disable_with_string
     assert_dom_equal(
       %(<input data-disable-with="Processing..." data-confirm="Are you sure?" name='commit' type="submit" value="Save" />),
-      submit_tag("Save", { "data-disable-with" => "Processing...", "data-confirm" => "Are you sure?" })
+      submit_tag("Save", "data-disable-with" => "Processing...", "data-confirm" => "Are you sure?")
     )
   end
 
   def test_submit_tag_having_data_disable_with_boolean
     assert_dom_equal(
       %(<input data-confirm="Are you sure?" name='commit' type="submit" value="Save" />),
-      submit_tag("Save", { "data-disable-with" => false, "data-confirm" => "Are you sure?" })
+      submit_tag("Save", "data-disable-with" => false, "data-confirm" => "Are you sure?")
     )
   end
 
   def test_submit_tag_having_data_hash_disable_with_boolean
     assert_dom_equal(
       %(<input data-confirm="Are you sure?" name='commit' type="submit" value="Save" />),
-      submit_tag("Save", { :data => { :confirm => "Are you sure?", :disable_with => false } })
+      submit_tag("Save", data: { confirm: "Are you sure?", disable_with: false })
     )
   end
 
   def test_submit_tag_with_no_onclick_options
     assert_dom_equal(
       %(<input name='commit' data-disable-with="Saving..." type="submit" value="Save" />),
-      submit_tag("Save", :data => { :disable_with => "Saving..." })
+      submit_tag("Save", data: { disable_with: "Saving..." })
     )
   end
 
   def test_submit_tag_with_confirmation
     assert_dom_equal(
       %(<input name='commit' type='submit' value='Save' data-confirm="Are you sure?" data-disable-with="Save" />),
-      submit_tag("Save", :data => { :confirm => "Are you sure?" })
+      submit_tag("Save", data: { confirm: "Are you sure?" })
     )
   end
 
   def test_submit_tag_doesnt_have_data_disable_with_twice
     assert_equal(
       %(<input type="submit" name="commit" value="Save" data-confirm="Are you sure?" data-disable-with="Processing..." />),
-      submit_tag("Save", { "data-disable-with" => "Processing...", "data-confirm" => "Are you sure?" })
+      submit_tag("Save", "data-disable-with" => "Processing...", "data-confirm" => "Are you sure?")
+    )
+  end
+
+  def test_submit_tag_doesnt_have_data_disable_with_twice_with_hash
+    assert_equal(
+      %(<input type="submit" name="commit" value="Save" data-disable-with="Processing..." />),
+      submit_tag("Save", data: { disable_with: "Processing..." })
     )
   end
 
@@ -517,7 +569,6 @@ class FormTagHelperTest < ActionView::TestCase
     )
   end
 
-
   def test_button_tag
     assert_dom_equal(
       %(<button name="button" type="submit">Button</button>),
@@ -528,56 +579,56 @@ class FormTagHelperTest < ActionView::TestCase
   def test_button_tag_with_submit_type
     assert_dom_equal(
       %(<button name="button" type="submit">Save</button>),
-      button_tag("Save", :type => "submit")
+      button_tag("Save", type: "submit")
     )
   end
 
   def test_button_tag_with_button_type
     assert_dom_equal(
       %(<button name="button" type="button">Button</button>),
-      button_tag("Button", :type => "button")
+      button_tag("Button", type: "button")
     )
   end
 
   def test_button_tag_with_reset_type
     assert_dom_equal(
       %(<button name="button" type="reset">Reset</button>),
-      button_tag("Reset", :type => "reset")
+      button_tag("Reset", type: "reset")
     )
   end
 
   def test_button_tag_with_disabled_option
     assert_dom_equal(
       %(<button name="button" type="reset" disabled="disabled">Reset</button>),
-      button_tag("Reset", :type => "reset", :disabled => true)
+      button_tag("Reset", type: "reset", disabled: true)
     )
   end
 
   def test_button_tag_escape_content
     assert_dom_equal(
       %(<button name="button" type="reset" disabled="disabled">&lt;b&gt;Reset&lt;/b&gt;</button>),
-      button_tag("<b>Reset</b>", :type => "reset", :disabled => true)
+      button_tag("<b>Reset</b>", type: "reset", disabled: true)
     )
   end
 
   def test_button_tag_with_block
-    assert_dom_equal('<button name="button" type="submit">Content</button>', button_tag { 'Content' })
+    assert_dom_equal('<button name="button" type="submit">Content</button>', button_tag { "Content" })
   end
 
   def test_button_tag_with_block_and_options
-    output = button_tag(:name => 'temptation', :type => 'button') { content_tag(:strong, 'Do not press me') }
+    output = button_tag(name: "temptation", type: "button") { content_tag(:strong, "Do not press me") }
     assert_dom_equal('<button name="temptation" type="button"><strong>Do not press me</strong></button>', output)
   end
 
   def test_button_tag_defaults_with_block_and_options
-    output = button_tag(:name => 'temptation', :value => 'within') { content_tag(:strong, 'Do not press me') }
+    output = button_tag(name: "temptation", value: "within") { content_tag(:strong, "Do not press me") }
     assert_dom_equal('<button name="temptation" value="within" type="submit" ><strong>Do not press me</strong></button>', output)
   end
 
   def test_button_tag_with_confirmation
     assert_dom_equal(
       %(<button name="button" type="submit" data-confirm="Are you sure?">Save</button>),
-      button_tag("Save", :type => "submit", :data => { :confirm => "Are you sure?" })
+      button_tag("Save", type: "submit", data: { confirm: "Are you sure?" })
     )
   end
 
@@ -590,8 +641,8 @@ class FormTagHelperTest < ActionView::TestCase
 
   def test_image_submit_tag_with_confirmation
     assert_dom_equal(
-      %(<input alt="Save" type="image" src="/images/save.gif" data-confirm="Are you sure?" />),
-      image_submit_tag("save.gif", :data => { :confirm => "Are you sure?" })
+      %(<input type="image" src="/images/save.gif" data-confirm="Are you sure?" />),
+      image_submit_tag("save.gif", data: { confirm: "Are you sure?" })
     )
   end
 
@@ -621,10 +672,8 @@ class FormTagHelperTest < ActionView::TestCase
   end
 
   def test_datetime_field_tag
-    expected = %{<input id="appointment" name="appointment" type="datetime" />}
-    assert_deprecated do
-      assert_dom_equal(expected, datetime_field_tag("appointment"))
-    end
+    expected = %{<input id="appointment" name="appointment" type="datetime-local" />}
+    assert_dom_equal(expected, datetime_field_tag("appointment"))
   end
 
   def test_datetime_local_field_tag
@@ -654,12 +703,12 @@ class FormTagHelperTest < ActionView::TestCase
 
   def test_number_field_tag
     expected = %{<input name="quantity" max="9" id="quantity" type="number" min="1" />}
-    assert_dom_equal(expected, number_field_tag("quantity", nil, :in => 1...10))
+    assert_dom_equal(expected, number_field_tag("quantity", nil, in: 1...10))
   end
 
   def test_range_input_tag
     expected = %{<input name="volume" step="0.1" max="11" id="volume" type="range" min="0" />}
-    assert_dom_equal(expected, range_field_tag("volume", nil, :in => 0..11, :step => 0.1))
+    assert_dom_equal(expected, range_field_tag("volume", nil, in: 0..11, step: 0.1))
   end
 
   def test_field_set_tag_in_erb
@@ -695,33 +744,33 @@ class FormTagHelperTest < ActionView::TestCase
   end
 
   def test_text_area_tag_options_symbolize_keys_side_effects
-    options = { :option => "random_option" }
+    options = { option: "random_option" }
     text_area_tag "body", "hello world", options
-    assert_equal options, { :option => "random_option" }
+    assert_equal({ option: "random_option" }, options)
   end
 
   def test_submit_tag_options_symbolize_keys_side_effects
-    options = { :option => "random_option" }
+    options = { option: "random_option" }
     submit_tag "submit value", options
-    assert_equal options, { :option => "random_option" }
+    assert_equal({ option: "random_option" }, options)
   end
 
   def test_button_tag_options_symbolize_keys_side_effects
-    options = { :option => "random_option" }
+    options = { option: "random_option" }
     button_tag "button value", options
-    assert_equal options, { :option => "random_option" }
+    assert_equal({ option: "random_option" }, options)
   end
 
   def test_image_submit_tag_options_symbolize_keys_side_effects
-    options = { :option => "random_option" }
+    options = { option: "random_option" }
     image_submit_tag "submit source", options
-    assert_equal options, { :option => "random_option" }
+    assert_equal({ option: "random_option" }, options)
   end
 
   def test_image_label_tag_options_symbolize_keys_side_effects
-    options = { :option => "random_option" }
+    options = { option: "random_option" }
     label_tag "submit source", "title", options
-    assert_equal options, { :option => "random_option" }
+    assert_equal({ option: "random_option" }, options)
   end
 
   def protect_against_forgery?
@@ -730,7 +779,7 @@ class FormTagHelperTest < ActionView::TestCase
 
   private
 
-  def root_elem(rendered_content)
-    Nokogiri::HTML::DocumentFragment.parse(rendered_content).children.first # extract from nodeset
-  end
+    def root_elem(rendered_content)
+      Nokogiri::HTML::DocumentFragment.parse(rendered_content).children.first # extract from nodeset
+    end
 end
diff --git a/actionview/test/template/html_test.rb b/actionview/test/template/html_test.rb
index 549c12c88c..5cdff74d60 100644
--- a/actionview/test/template/html_test.rb
+++ b/actionview/test/template/html_test.rb
@@ -1,17 +1,19 @@
-require 'abstract_unit'
+# frozen_string_literal: true
+
+require "abstract_unit"
 
 class HTMLTest < ActiveSupport::TestCase
-  test 'formats returns symbol for recognized MIME type' do
-    assert_equal [:html], ActionView::Template::HTML.new('', :html).formats
+  test "formats returns symbol for recognized MIME type" do
+    assert_equal [:html], ActionView::Template::HTML.new("", :html).formats
   end
 
-  test 'formats returns string for recognized MIME type when MIME does not have symbol' do
+  test "formats returns string for recognized MIME type when MIME does not have symbol" do
     foo = Mime::Type.lookup("foo")
     assert_nil foo.to_sym
-    assert_equal ['foo'], ActionView::Template::HTML.new('', foo).formats
+    assert_equal ["foo"], ActionView::Template::HTML.new("", foo).formats
   end
 
-  test 'formats returns string for unknown MIME type' do
-    assert_equal ['foo'], ActionView::Template::HTML.new('', 'foo').formats
+  test "formats returns string for unknown MIME type" do
+    assert_equal ["foo"], ActionView::Template::HTML.new("", "foo").formats
   end
 end
diff --git a/actionview/test/template/javascript_helper_test.rb b/actionview/test/template/javascript_helper_test.rb
index 9f1535ef53..a72bc6c2fe 100644
--- a/actionview/test/template/javascript_helper_test.rb
+++ b/actionview/test/template/javascript_helper_test.rb
@@ -1,14 +1,20 @@
-require 'abstract_unit'
+# frozen_string_literal: true
+
+require "abstract_unit"
 
 class JavaScriptHelperTest < ActionView::TestCase
   tests ActionView::Helpers::JavaScriptHelper
 
   attr_accessor :output_buffer
+  attr_reader :request
 
   setup do
     @old_escape_html_entities_in_json = ActiveSupport.escape_html_entities_in_json
-    ActiveSupport.escape_html_entities_in_json  = true
+    ActiveSupport.escape_html_entities_in_json = true
     @template = self
+    @request = Class.new do
+      def send_early_hints(links) end
+    end.new
   end
 
   def teardown
@@ -16,12 +22,12 @@ class JavaScriptHelperTest < ActionView::TestCase
   end
 
   def test_escape_javascript
-    assert_equal '', escape_javascript(nil)
+    assert_equal "", escape_javascript(nil)
     assert_equal %(This \\"thing\\" is really\\n netos\\'), escape_javascript(%(This "thing" is really\n netos'))
-    assert_equal %(backslash\\\\test), escape_javascript( %(backslash\\test) )
+    assert_equal %(backslash\\\\test), escape_javascript(%(backslash\\test))
     assert_equal %(dont <\\/close> tags), escape_javascript(%(dont </close> tags))
-    assert_equal %(unicode &#x2028; newline), escape_javascript(%(unicode \342\200\250 newline).force_encoding(Encoding::UTF_8).encode!)
-    assert_equal %(unicode &#x2029; newline), escape_javascript(%(unicode \342\200\251 newline).force_encoding(Encoding::UTF_8).encode!)
+    assert_equal %(unicode &#x2028; newline), escape_javascript(%(unicode \342\200\250 newline).dup.force_encoding(Encoding::UTF_8).encode!)
+    assert_equal %(unicode &#x2029; newline), escape_javascript(%(unicode \342\200\251 newline).dup.force_encoding(Encoding::UTF_8).encode!)
 
     assert_equal %(dont <\\/close> tags), j(%(dont </close> tags))
   end
@@ -36,24 +42,24 @@ class JavaScriptHelperTest < ActionView::TestCase
   end
 
   def test_javascript_tag
-    self.output_buffer = 'foo'
+    self.output_buffer = "foo"
 
     assert_dom_equal "<script>\n//<![CDATA[\nalert('hello')\n//]]>\n</script>",
       javascript_tag("alert('hello')")
 
-    assert_equal 'foo', output_buffer, 'javascript_tag without a block should not concat to output_buffer'
+    assert_equal "foo", output_buffer, "javascript_tag without a block should not concat to output_buffer"
   end
 
   # Setting the :extname option will control what extension (if any) is appended to the url for assets
   def test_javascript_include_tag
-    assert_dom_equal "<script src='/foo.js'></script>",  javascript_include_tag('/foo')
-    assert_dom_equal "<script src='/foo'></script>",     javascript_include_tag('/foo', extname: false )
-    assert_dom_equal "<script src='/foo.bar'></script>", javascript_include_tag('/foo', extname: '.bar' )
+    assert_dom_equal "<script src='/foo.js'></script>",  javascript_include_tag("/foo")
+    assert_dom_equal "<script src='/foo'></script>",     javascript_include_tag("/foo", extname: false)
+    assert_dom_equal "<script src='/foo.bar'></script>", javascript_include_tag("/foo", extname: ".bar")
   end
 
   def test_javascript_tag_with_options
     assert_dom_equal "<script id=\"the_js_tag\">\n//<![CDATA[\nalert('hello')\n//]]>\n</script>",
-      javascript_tag("alert('hello')", :id => "the_js_tag")
+      javascript_tag("alert('hello')", id: "the_js_tag")
   end
 
   def test_javascript_cdata_section
diff --git a/actionview/test/template/log_subscriber_test.rb b/actionview/test/template/log_subscriber_test.rb
index 7683444bf0..7f4fd25573 100644
--- a/actionview/test/template/log_subscriber_test.rb
+++ b/actionview/test/template/log_subscriber_test.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require "abstract_unit"
 require "active_support/log_subscriber/test_helper"
 require "action_view/log_subscriber"
@@ -8,11 +10,14 @@ class AVLogSubscriberTest < ActiveSupport::TestCase
 
   def setup
     super
-    view_paths = ActionController::Base.view_paths
+
+    view_paths     = ActionController::Base.view_paths
     lookup_context = ActionView::LookupContext.new(view_paths, {}, ["test"])
-    renderer = ActionView::Renderer.new(lookup_context)
-    @view = ActionView::Base.new(renderer, {})
+    renderer       = ActionView::Renderer.new(lookup_context)
+    @view          = ActionView::Base.new(renderer, {})
+
     ActionView::LogSubscriber.attach_to :action_view
+
     unless Rails.respond_to?(:root)
       @defined_root = true
       def Rails.root; :defined_root; end # Minitest `stub` expects the method to be defined.
@@ -21,18 +26,32 @@ class AVLogSubscriberTest < ActiveSupport::TestCase
 
   def teardown
     super
+
     ActiveSupport::LogSubscriber.log_subscribers.clear
+
     # We need to undef `root`, RenderTestCases don't want this to be defined
-    Rails.instance_eval { undef :root } if @defined_root
+    Rails.instance_eval { undef :root } if defined?(@defined_root)
   end
 
   def set_logger(logger)
     ActionView::Base.logger = logger
   end
 
+  def set_cache_controller
+    controller = ActionController::Base.new
+    controller.perform_caching = true
+    controller.cache_store = ActiveSupport::Cache::MemoryStore.new
+    @view.controller = controller
+  end
+
+  def set_view_cache_dependencies
+    def @view.view_cache_dependencies; []; end
+    def @view.combined_fragment_cache_key(*); "ahoy `controller` dependency"; end
+  end
+
   def test_render_file_template
     Rails.stub(:root, File.expand_path(FIXTURE_LOAD_PATH)) do
-      @view.render(:file => "test/hello_world")
+      @view.render(file: "test/hello_world")
       wait
 
       assert_equal 2, @logger.logged(:info).size
@@ -43,7 +62,7 @@ class AVLogSubscriberTest < ActiveSupport::TestCase
 
   def test_render_text_template
     Rails.stub(:root, File.expand_path(FIXTURE_LOAD_PATH)) do
-      @view.render(:text => "TEXT")
+      @view.render(plain: "TEXT")
       wait
 
       assert_equal 2, @logger.logged(:info).size
@@ -54,7 +73,7 @@ class AVLogSubscriberTest < ActiveSupport::TestCase
 
   def test_render_inline_template
     Rails.stub(:root, File.expand_path(FIXTURE_LOAD_PATH)) do
-      @view.render(:inline => "<%= 'TEXT' %>")
+      @view.render(inline: "<%= 'TEXT' %>")
       wait
 
       assert_equal 2, @logger.logged(:info).size
@@ -63,29 +82,106 @@ class AVLogSubscriberTest < ActiveSupport::TestCase
     end
   end
 
-  def test_render_partial_template
+  def test_render_partial_with_implicit_path
     Rails.stub(:root, File.expand_path(FIXTURE_LOAD_PATH)) do
-      @view.render(:partial => "test/customer")
+      @view.render(Customer.new("david"), greeting: "hi")
       wait
 
       assert_equal 1, @logger.logged(:info).size
-      assert_match(/Rendered test\/_customer.erb/, @logger.logged(:info).last)
+      assert_match(/Rendered customers\/_customer\.html\.erb/, @logger.logged(:info).last)
     end
   end
 
-  def test_render_partial_with_implicit_path
+  def test_render_partial_with_cache_missed
     Rails.stub(:root, File.expand_path(FIXTURE_LOAD_PATH)) do
-      @view.render(Customer.new("david"), :greeting => "hi")
+      set_view_cache_dependencies
+      set_cache_controller
+
+      @view.render(partial: "test/cached_customer", locals: { cached_customer: Customer.new("david") })
       wait
 
       assert_equal 1, @logger.logged(:info).size
-      assert_match(/Rendered customers\/_customer\.html\.erb/, @logger.logged(:info).last)
+      assert_match(/Rendered test\/_cached_customer\.erb (.*) \[cache miss\]/, @logger.logged(:info).last)
+    end
+  end
+
+  def test_render_partial_with_cache_hitted
+    Rails.stub(:root, File.expand_path(FIXTURE_LOAD_PATH)) do
+      set_view_cache_dependencies
+      set_cache_controller
+
+      # Second render should hit cache.
+      @view.render(partial: "test/cached_customer", locals: { cached_customer: Customer.new("david") })
+      @view.render(partial: "test/cached_customer", locals: { cached_customer: Customer.new("david") })
+      wait
+
+      assert_equal 2, @logger.logged(:info).size
+      assert_match(/Rendered test\/_cached_customer\.erb (.*) \[cache hit\]/, @logger.logged(:info).last)
+    end
+  end
+
+  def test_render_uncached_outer_partial_with_inner_cached_partial_wont_mix_cache_hits_or_misses
+    Rails.stub(:root, File.expand_path(FIXTURE_LOAD_PATH)) do
+      set_view_cache_dependencies
+      set_cache_controller
+
+      @view.render(partial: "test/nested_cached_customer", locals: { cached_customer: Customer.new("Stan") })
+      wait
+      *, cached_inner, uncached_outer = @logger.logged(:info)
+      assert_match(/Rendered test\/_cached_customer\.erb (.*) \[cache miss\]/, cached_inner)
+      assert_match(/Rendered test\/_nested_cached_customer\.erb \(.*?ms\)$/, uncached_outer)
+
+      # Second render hits the cache for the _cached_customer partial. Outer template's log shouldn't be affected.
+      @view.render(partial: "test/nested_cached_customer", locals: { cached_customer: Customer.new("Stan") })
+      wait
+      *, cached_inner, uncached_outer = @logger.logged(:info)
+      assert_match(/Rendered test\/_cached_customer\.erb (.*) \[cache hit\]/, cached_inner)
+      assert_match(/Rendered test\/_nested_cached_customer\.erb \(.*?ms\)$/, uncached_outer)
+    end
+  end
+
+  def test_render_cached_outer_partial_with_cached_inner_partial
+    Rails.stub(:root, File.expand_path(FIXTURE_LOAD_PATH)) do
+      set_view_cache_dependencies
+      set_cache_controller
+
+      @view.render(partial: "test/cached_nested_cached_customer", locals: { cached_customer: Customer.new("Stan") })
+      wait
+      *, cached_inner, cached_outer = @logger.logged(:info)
+      assert_match(/Rendered test\/_cached_customer\.erb (.*) \[cache miss\]/, cached_inner)
+      assert_match(/Rendered test\/_cached_nested_cached_customer\.erb (.*) \[cache miss\]/, cached_outer)
+
+      # One render: inner partial skipped, because the outer has been cached.
+      assert_difference -> { @logger.logged(:info).size }, +1 do
+        @view.render(partial: "test/cached_nested_cached_customer", locals: { cached_customer: Customer.new("Stan") })
+        wait
+      end
+      assert_match(/Rendered test\/_cached_nested_cached_customer\.erb (.*) \[cache hit\]/, @logger.logged(:info).last)
+    end
+  end
+
+  def test_render_partial_with_cache_hitted_and_missed
+    Rails.stub(:root, File.expand_path(FIXTURE_LOAD_PATH)) do
+      set_view_cache_dependencies
+      set_cache_controller
+
+      @view.render(partial: "test/cached_customer", locals: { cached_customer: Customer.new("david") })
+      wait
+      assert_match(/Rendered test\/_cached_customer\.erb (.*) \[cache miss\]/, @logger.logged(:info).last)
+
+      @view.render(partial: "test/cached_customer", locals: { cached_customer: Customer.new("david") })
+      wait
+      assert_match(/Rendered test\/_cached_customer\.erb (.*) \[cache hit\]/, @logger.logged(:info).last)
+
+      @view.render(partial: "test/cached_customer", locals: { cached_customer: Customer.new("Stan") })
+      wait
+      assert_match(/Rendered test\/_cached_customer\.erb (.*) \[cache miss\]/, @logger.logged(:info).last)
     end
   end
 
   def test_render_collection_template
     Rails.stub(:root, File.expand_path(FIXTURE_LOAD_PATH)) do
-      @view.render(:partial => "test/customer", :collection => [ Customer.new("david"), Customer.new("mary") ])
+      @view.render(partial: "test/customer", collection: [ Customer.new("david"), Customer.new("mary") ])
       wait
 
       assert_equal 1, @logger.logged(:info).size
@@ -95,7 +191,7 @@ class AVLogSubscriberTest < ActiveSupport::TestCase
 
   def test_render_collection_with_implicit_path
     Rails.stub(:root, File.expand_path(FIXTURE_LOAD_PATH)) do
-      @view.render([ Customer.new("david"), Customer.new("mary") ], :greeting => "hi")
+      @view.render([ Customer.new("david"), Customer.new("mary") ], greeting: "hi")
       wait
 
       assert_equal 1, @logger.logged(:info).size
@@ -105,7 +201,7 @@ class AVLogSubscriberTest < ActiveSupport::TestCase
 
   def test_render_collection_template_without_path
     Rails.stub(:root, File.expand_path(FIXTURE_LOAD_PATH)) do
-      @view.render([ GoodCustomer.new("david"), Customer.new("mary") ], :greeting => "hi")
+      @view.render([ GoodCustomer.new("david"), Customer.new("mary") ], greeting: "hi")
       wait
 
       assert_equal 1, @logger.logged(:info).size
@@ -115,11 +211,10 @@ class AVLogSubscriberTest < ActiveSupport::TestCase
 
   def test_render_collection_with_cached_set
     Rails.stub(:root, File.expand_path(FIXTURE_LOAD_PATH)) do
-      def @view.view_cache_dependencies; []; end
-      def @view.fragment_cache_key(*); 'ahoy `controller` dependency'; end
+      set_view_cache_dependencies
 
-      @view.render(partial: 'customers/customer', collection: [ Customer.new('david'), Customer.new('mary') ], cached: true,
-        locals: { greeting: 'hi' })
+      @view.render(partial: "customers/customer", collection: [ Customer.new("david"), Customer.new("mary") ], cached: true,
+        locals: { greeting: "hi" })
       wait
 
       assert_equal 1, @logger.logged(:info).size
diff --git a/actionview/test/template/lookup_context_test.rb b/actionview/test/template/lookup_context_test.rb
index 2e3a3f9bae..402ee9b6ae 100644
--- a/actionview/test/template/lookup_context_test.rb
+++ b/actionview/test/template/lookup_context_test.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require "abstract_unit"
 require "abstract_controller/rendering"
 
@@ -120,8 +122,8 @@ class LookupContextTest < ActiveSupport::TestCase
 
     @lookup_context.with_fallbacks do
       assert_equal 3, @lookup_context.view_paths.size
-      assert @lookup_context.view_paths.include?(ActionView::FallbackFileSystemResolver.new(""))
-      assert @lookup_context.view_paths.include?(ActionView::FallbackFileSystemResolver.new("/"))
+      assert_includes @lookup_context.view_paths, ActionView::FallbackFileSystemResolver.new("")
+      assert_includes @lookup_context.view_paths, ActionView::FallbackFileSystemResolver.new("/")
     end
   end
 
@@ -279,10 +281,9 @@ class TestMissingTemplate < ActiveSupport::TestCase
 
   test "if a single prefix is passed as a string and the lookup fails, MissingTemplate accepts it" do
     e = assert_raise ActionView::MissingTemplate do
-      details = {:handlers=>[], :formats=>[], :variants=>[], :locale=>[]}
+      details = { handlers: [], formats: [], variants: [], locale: [] }
       @lookup_context.view_paths.find("foo", "parent", true, details)
     end
     assert_match %r{Missing partial parent/_foo with .* Searched in:\n  \* "/Path/to/views"\n}, e.message
   end
-
 end
diff --git a/actionview/test/template/number_helper_test.rb b/actionview/test/template/number_helper_test.rb
index ace3e950b8..e92bf66203 100644
--- a/actionview/test/template/number_helper_test.rb
+++ b/actionview/test/template/number_helper_test.rb
@@ -1,10 +1,12 @@
+# frozen_string_literal: true
+
 require "abstract_unit"
 
 class NumberHelperTest < ActionView::TestCase
   tests ActionView::Helpers::NumberHelper
 
   def test_number_to_phone
-    assert_equal nil, number_to_phone(nil)
+    assert_nil number_to_phone(nil)
     assert_equal "555-1234", number_to_phone(5551234)
     assert_equal "(800) 555-1212 x 123", number_to_phone(8005551212, area_code: true, extension: 123)
     assert_equal "+18005551212", number_to_phone(8005551212, country_code: 1, delimiter: "")
@@ -13,23 +15,23 @@ class NumberHelperTest < ActionView::TestCase
   end
 
   def test_number_to_currency
-    assert_equal nil, number_to_currency(nil)
+    assert_nil number_to_currency(nil)
     assert_equal "$1,234,567,890.50", number_to_currency(1234567890.50)
     assert_equal "$1,234,567,892", number_to_currency(1234567891.50, precision: 0)
     assert_equal "1,234,567,890.50 - K&#269;", number_to_currency("-1234567890.50", unit: raw("K&#269;"), format: "%n %u", negative_format: "%n - %u")
     assert_equal "&amp;pound;1,234,567,890.50", number_to_currency("1234567890.50", unit: "&pound;")
     assert_equal "&lt;b&gt;1,234,567,890.50&lt;/b&gt; $", number_to_currency("1234567890.50", format: "<b>%n</b> %u")
     assert_equal "&lt;b&gt;1,234,567,890.50&lt;/b&gt; $", number_to_currency("-1234567890.50", negative_format: "<b>%n</b> %u")
-    assert_equal "&lt;b&gt;1,234,567,890.50&lt;/b&gt; $", number_to_currency("-1234567890.50", 'negative_format' => "<b>%n</b> %u")
-    assert_equal '₹ 12,30,000.00', number_to_currency(1230000, delimiter_pattern: /(\d+?)(?=(\d\d)+(\d)(?!\d))/, unit: '₹', format: "%u %n")
+    assert_equal "&lt;b&gt;1,234,567,890.50&lt;/b&gt; $", number_to_currency("-1234567890.50", "negative_format" => "<b>%n</b> %u")
+    assert_equal "₹ 12,30,000.00", number_to_currency(1230000, delimiter_pattern: /(\d+?)(?=(\d\d)+(\d)(?!\d))/, unit: "₹", format: "%u %n")
   end
 
   def test_number_to_percentage
-    assert_equal nil, number_to_percentage(nil)
+    assert_nil number_to_percentage(nil)
     assert_equal "100.000%", number_to_percentage(100)
-    assert_equal "100.000 %", number_to_percentage(100, format: '%n %')
-    assert_equal "&lt;b&gt;100.000&lt;/b&gt; %", number_to_percentage(100, format: '<b>%n</b> %')
-    assert_equal "<b>100.000</b> %", number_to_percentage(100, format: raw('<b>%n</b> %'))
+    assert_equal "100.000 %", number_to_percentage(100, format: "%n %")
+    assert_equal "&lt;b&gt;100.000&lt;/b&gt; %", number_to_percentage(100, format: "<b>%n</b> %")
+    assert_equal "<b>100.000</b> %", number_to_percentage(100, format: raw("<b>%n</b> %"))
     assert_equal "100%", number_to_percentage(100, precision: 0)
     assert_equal "123.4%", number_to_percentage(123.400, precision: 3, strip_insignificant_zeros: true)
     assert_equal "1.000,000%", number_to_percentage(1000, delimiter: ".", separator: ",")
@@ -43,13 +45,13 @@ class NumberHelperTest < ActionView::TestCase
   end
 
   def test_number_with_delimiter
-    assert_equal nil, number_with_delimiter(nil)
+    assert_nil number_with_delimiter(nil)
     assert_equal "12,345,678", number_with_delimiter(12345678)
     assert_equal "0", number_with_delimiter(0)
   end
 
   def test_number_with_precision
-    assert_equal nil, number_with_precision(nil)
+    assert_nil number_with_precision(nil)
     assert_equal "-111.235", number_with_precision(-111.2346)
     assert_equal "111.00", number_with_precision(111, precision: 2)
     assert_equal "0.00100", number_with_precision(0.001, precision: 5)
@@ -57,13 +59,13 @@ class NumberHelperTest < ActionView::TestCase
   end
 
   def test_number_to_human_size
-    assert_equal nil, number_to_human_size(nil)
+    assert_nil number_to_human_size(nil)
     assert_equal "3 Bytes", number_to_human_size(3.14159265)
     assert_equal "1.2 MB", number_to_human_size(1234567, precision: 2)
   end
 
   def test_number_to_human
-    assert_equal nil,   number_to_human(nil)
+    assert_nil number_to_human(nil)
     assert_equal "0",   number_to_human(0)
     assert_equal "1.23 Thousand", number_to_human(1234)
     assert_equal "489.0 Thousand", number_to_human(489000, precision: 4, strip_insignificant_zeros: false)
@@ -71,27 +73,27 @@ class NumberHelperTest < ActionView::TestCase
 
   def test_number_to_human_escape_units
     volume = { unit: "<b>ml</b>", thousand: "<b>lt</b>", million: "<b>m3</b>", trillion: "<b>km3</b>", quadrillion: "<b>Pl</b>" }
-    assert_equal '123 &lt;b&gt;lt&lt;/b&gt;', number_to_human(123456, :units => volume)
-    assert_equal '12 &lt;b&gt;ml&lt;/b&gt;', number_to_human(12, :units => volume)
-    assert_equal '1.23 &lt;b&gt;m3&lt;/b&gt;', number_to_human(1234567, :units => volume)
-    assert_equal '1.23 &lt;b&gt;km3&lt;/b&gt;', number_to_human(1_234_567_000_000, :units => volume)
-    assert_equal '1.23 &lt;b&gt;Pl&lt;/b&gt;', number_to_human(1_234_567_000_000_000, :units => volume)
+    assert_equal "123 &lt;b&gt;lt&lt;/b&gt;", number_to_human(123456, units: volume)
+    assert_equal "12 &lt;b&gt;ml&lt;/b&gt;", number_to_human(12, units: volume)
+    assert_equal "1.23 &lt;b&gt;m3&lt;/b&gt;", number_to_human(1234567, units: volume)
+    assert_equal "1.23 &lt;b&gt;km3&lt;/b&gt;", number_to_human(1_234_567_000_000, units: volume)
+    assert_equal "1.23 &lt;b&gt;Pl&lt;/b&gt;", number_to_human(1_234_567_000_000_000, units: volume)
 
-    #Including fractionals
+    # Including fractionals
     distance = { mili: "<b>mm</b>", centi: "<b>cm</b>", deci: "<b>dm</b>", unit: "<b>m</b>",
                  ten: "<b>dam</b>", hundred: "<b>hm</b>", thousand: "<b>km</b>",
-                 micro: "<b>um</b>", nano: "<b>nm</b>", pico: "<b>pm</b>", femto: "<b>fm</b>"}
-    assert_equal '1.23 &lt;b&gt;mm&lt;/b&gt;', number_to_human(0.00123, :units => distance)
-    assert_equal '1.23 &lt;b&gt;cm&lt;/b&gt;', number_to_human(0.0123, :units => distance)
-    assert_equal '1.23 &lt;b&gt;dm&lt;/b&gt;', number_to_human(0.123, :units => distance)
-    assert_equal '1.23 &lt;b&gt;m&lt;/b&gt;', number_to_human(1.23, :units => distance)
-    assert_equal '1.23 &lt;b&gt;dam&lt;/b&gt;', number_to_human(12.3, :units => distance)
-    assert_equal '1.23 &lt;b&gt;hm&lt;/b&gt;', number_to_human(123, :units => distance)
-    assert_equal '1.23 &lt;b&gt;km&lt;/b&gt;', number_to_human(1230, :units => distance)
-    assert_equal '1.23 &lt;b&gt;um&lt;/b&gt;', number_to_human(0.00000123, :units => distance)
-    assert_equal '1.23 &lt;b&gt;nm&lt;/b&gt;', number_to_human(0.00000000123, :units => distance)
-    assert_equal '1.23 &lt;b&gt;pm&lt;/b&gt;', number_to_human(0.00000000000123, :units => distance)
-    assert_equal '1.23 &lt;b&gt;fm&lt;/b&gt;', number_to_human(0.00000000000000123, :units => distance)
+                 micro: "<b>um</b>", nano: "<b>nm</b>", pico: "<b>pm</b>", femto: "<b>fm</b>" }
+    assert_equal "1.23 &lt;b&gt;mm&lt;/b&gt;", number_to_human(0.00123, units: distance)
+    assert_equal "1.23 &lt;b&gt;cm&lt;/b&gt;", number_to_human(0.0123, units: distance)
+    assert_equal "1.23 &lt;b&gt;dm&lt;/b&gt;", number_to_human(0.123, units: distance)
+    assert_equal "1.23 &lt;b&gt;m&lt;/b&gt;", number_to_human(1.23, units: distance)
+    assert_equal "1.23 &lt;b&gt;dam&lt;/b&gt;", number_to_human(12.3, units: distance)
+    assert_equal "1.23 &lt;b&gt;hm&lt;/b&gt;", number_to_human(123, units: distance)
+    assert_equal "1.23 &lt;b&gt;km&lt;/b&gt;", number_to_human(1230, units: distance)
+    assert_equal "1.23 &lt;b&gt;um&lt;/b&gt;", number_to_human(0.00000123, units: distance)
+    assert_equal "1.23 &lt;b&gt;nm&lt;/b&gt;", number_to_human(0.00000000123, units: distance)
+    assert_equal "1.23 &lt;b&gt;pm&lt;/b&gt;", number_to_human(0.00000000000123, units: distance)
+    assert_equal "1.23 &lt;b&gt;fm&lt;/b&gt;", number_to_human(0.00000000000000123, units: distance)
   end
 
   def test_number_helpers_escape_delimiter_and_separator
@@ -116,9 +118,9 @@ class NumberHelperTest < ActionView::TestCase
   end
 
   def test_number_to_human_with_custom_translation_scope
-    I18n.backend.store_translations 'ts',
-      :custom_units_for_number_to_human => {:mili => "mm", :centi => "cm", :deci => "dm", :unit => "m", :ten => "dam", :hundred => "hm", :thousand => "km"}
-    assert_equal "1.01 cm", number_to_human(0.0101, :locale => 'ts', :units => :custom_units_for_number_to_human)
+    I18n.backend.store_translations "ts",
+      custom_units_for_number_to_human: { mili: "mm", centi: "cm", deci: "dm", unit: "m", ten: "dam", hundred: "hm", thousand: "km" }
+    assert_equal "1.01 cm", number_to_human(0.0101, locale: "ts", units: :custom_units_for_number_to_human)
   ensure
     I18n.reload!
   end
diff --git a/actionview/test/template/output_safety_helper_test.rb b/actionview/test/template/output_safety_helper_test.rb
index b940c9dd36..b5e9a77105 100644
--- a/actionview/test/template/output_safety_helper_test.rb
+++ b/actionview/test/template/output_safety_helper_test.rb
@@ -1,4 +1,6 @@
-require 'abstract_unit'
+# frozen_string_literal: true
+
+require "abstract_unit"
 
 class OutputSafetyHelperTest < ActionView::TestCase
   tests ActionView::Helpers::OutputSafetyHelper
@@ -26,11 +28,27 @@ class OutputSafetyHelperTest < ActionView::TestCase
   end
 
   test "safe_join should work recursively similarly to Array.join" do
-    joined = safe_join(['a',['b','c']], ':')
-    assert_equal 'a:b:c', joined
+    joined = safe_join(["a", ["b", "c"]], ":")
+    assert_equal "a:b:c", joined
 
-    joined = safe_join(['"a"',['<b>','<c>']], ' <br/> ')
-    assert_equal '&quot;a&quot; &lt;br/&gt; &lt;b&gt; &lt;br/&gt; &lt;c&gt;', joined
+    joined = safe_join(['"a"', ["<b>", "<c>"]], " <br/> ")
+    assert_equal "&quot;a&quot; &lt;br/&gt; &lt;b&gt; &lt;br/&gt; &lt;c&gt;", joined
+  end
+
+  test "safe_join should return the safe string separated by $, when second argument is not passed" do
+    default_delimeter = $,
+
+    begin
+      $, = nil
+      joined = safe_join(["a", "b"])
+      assert_equal "ab", joined
+
+      $, = "|"
+      joined = safe_join(["a", "b"])
+      assert_equal "a|b", joined
+    ensure
+      $, = default_delimeter
+    end
   end
 
   test "to_sentence should escape non-html_safe values" do
@@ -50,9 +68,9 @@ class OutputSafetyHelperTest < ActionView::TestCase
   end
 
   test "to_sentence connector words are checked for html safety" do
-    assert_equal "one & two, and three", to_sentence(['one', 'two', 'three'], words_connector: ' & '.html_safe)
-    assert_equal "one & two", to_sentence(['one', 'two'], two_words_connector: ' & '.html_safe)
-    assert_equal "one, two &lt;script&gt;alert(1)&lt;/script&gt; three", to_sentence(['one', 'two', 'three'], last_word_connector: ' <script>alert(1)</script> ')
+    assert_equal "one & two, and three", to_sentence(["one", "two", "three"], words_connector: " & ".html_safe)
+    assert_equal "one & two", to_sentence(["one", "two"], two_words_connector: " & ".html_safe)
+    assert_equal "one, two &lt;script&gt;alert(1)&lt;/script&gt; three", to_sentence(["one", "two", "three"], last_word_connector: " <script>alert(1)</script> ")
   end
 
   test "to_sentence should not escape html_safe values" do
@@ -67,24 +85,35 @@ class OutputSafetyHelperTest < ActionView::TestCase
   end
 
   test "to_sentence handles blank strings" do
-    actual = to_sentence(['', 'two', 'three'])
+    actual = to_sentence(["", "two", "three"])
     assert actual.html_safe?
     assert_equal ", two, and three", actual
   end
 
   test "to_sentence handles nil values" do
-    actual = to_sentence([nil, 'two', 'three'])
+    actual = to_sentence([nil, "two", "three"])
     assert actual.html_safe?
     assert_equal ", two, and three", actual
   end
 
   test "to_sentence still supports ActiveSupports Array#to_sentence arguments" do
-    assert_equal "one two, and three", to_sentence(['one', 'two', 'three'], words_connector: ' ')
-    assert_equal "one & two, and three", to_sentence(['one', 'two', 'three'], words_connector: ' & '.html_safe)
-    assert_equal "onetwo, and three", to_sentence(['one', 'two', 'three'], words_connector: nil)
-    assert_equal "one, two, and also three", to_sentence(['one', 'two', 'three'], last_word_connector: ', and also ')
-    assert_equal "one, twothree", to_sentence(['one', 'two', 'three'], last_word_connector: nil)
-    assert_equal "one, two three", to_sentence(['one', 'two', 'three'], last_word_connector: ' ')
-    assert_equal "one, two and three", to_sentence(['one', 'two', 'three'], last_word_connector: ' and ')
+    assert_equal "one two, and three", to_sentence(["one", "two", "three"], words_connector: " ")
+    assert_equal "one & two, and three", to_sentence(["one", "two", "three"], words_connector: " & ".html_safe)
+    assert_equal "onetwo, and three", to_sentence(["one", "two", "three"], words_connector: nil)
+    assert_equal "one, two, and also three", to_sentence(["one", "two", "three"], last_word_connector: ", and also ")
+    assert_equal "one, twothree", to_sentence(["one", "two", "three"], last_word_connector: nil)
+    assert_equal "one, two three", to_sentence(["one", "two", "three"], last_word_connector: " ")
+    assert_equal "one, two and three", to_sentence(["one", "two", "three"], last_word_connector: " and ")
+  end
+
+  test "to_sentence is not affected by $," do
+    separator_was = $,
+    $, = "|"
+    begin
+      assert_equal "one and two", to_sentence(["one", "two"])
+      assert_equal "one, two, and three", to_sentence(["one", "two", "three"])
+    ensure
+      $, = separator_was
+    end
   end
 end
diff --git a/actionview/test/template/partial_iteration_test.rb b/actionview/test/template/partial_iteration_test.rb
index 695f9f1bef..06bbdabac0 100644
--- a/actionview/test/template/partial_iteration_test.rb
+++ b/actionview/test/template/partial_iteration_test.rb
@@ -1,5 +1,7 @@
-require 'abstract_unit'
-require 'action_view/renderer/partial_renderer'
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "action_view/renderer/partial_renderer"
 
 class PartialIterationTest < ActiveSupport::TestCase
   def test_has_size_and_index
diff --git a/actionview/test/template/record_identifier_test.rb b/actionview/test/template/record_identifier_test.rb
index 04898c0b0e..29012e943d 100644
--- a/actionview/test/template/record_identifier_test.rb
+++ b/actionview/test/template/record_identifier_test.rb
@@ -1,5 +1,7 @@
-require 'abstract_unit'
-require 'controller/fake_models'
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "controller/fake_models"
 
 class RecordIdentifierTest < ActiveSupport::TestCase
   include ActionView::RecordIdentifier
@@ -7,8 +9,8 @@ class RecordIdentifierTest < ActiveSupport::TestCase
   def setup
     @klass  = Comment
     @record = @klass.new
-    @singular = 'comment'
-    @plural = 'comments'
+    @singular = "comment"
+    @plural = "comments"
   end
 
   def test_dom_id_with_new_record
@@ -73,7 +75,7 @@ class RecordIdentifierWithoutActiveModelTest < ActiveSupport::TestCase
   end
 
   def test_dom_class
-    assert_equal 'airplane', dom_class(@record)
+    assert_equal "airplane", dom_class(@record)
   end
 
   def test_dom_class_with_prefix
@@ -86,6 +88,6 @@ class RecordIdentifierWithoutActiveModelTest < ActiveSupport::TestCase
   end
 
   def test_dom_class_as_singleton_method
-    assert_equal 'airplane', ActionView::RecordIdentifier.dom_class(@record)
+    assert_equal "airplane", ActionView::RecordIdentifier.dom_class(@record)
   end
 end
diff --git a/actionview/test/template/record_tag_helper_test.rb b/actionview/test/template/record_tag_helper_test.rb
index bfc5d04bed..7bbbfccdd0 100644
--- a/actionview/test/template/record_tag_helper_test.rb
+++ b/actionview/test/template/record_tag_helper_test.rb
@@ -1,4 +1,6 @@
-require 'abstract_unit'
+# frozen_string_literal: true
+
+require "abstract_unit"
 
 class RecordTagPost
   extend ActiveModel::Naming
@@ -14,7 +16,6 @@ class RecordTagPost
 end
 
 class RecordTagHelperTest < ActionView::TestCase
-
   tests ActionView::Helpers::RecordTagHelper
 
   def setup
diff --git a/actionview/test/template/render_test.rb b/actionview/test/template/render_test.rb
index ad93236d32..8782eb4430 100644
--- a/actionview/test/template/render_test.rb
+++ b/actionview/test/template/render_test.rb
@@ -1,25 +1,27 @@
-require 'abstract_unit'
-require 'controller/fake_models'
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "controller/fake_models"
 
 class TestController < ActionController::Base
 end
 
 module RenderTestCases
   def setup_view(paths)
-    @assigns = { :secret => 'in the sauce' }
+    @assigns = { secret: "in the sauce" }
     @view = Class.new(ActionView::Base) do
       def view_cache_dependencies; end
 
-      def fragment_cache_key(key)
-        ActiveSupport::Cache.expand_cache_key(key, :views)
+      def combined_fragment_cache_key(key)
+        [ :views, key ]
       end
     end.new(paths, @assigns)
 
     @controller_view = TestController.new.view_context
 
     # Reload and register danish language for testing
-    I18n.backend.store_translations 'da', {}
-    I18n.backend.store_translations 'pt-BR', {}
+    I18n.backend.store_translations "da", {}
+    I18n.backend.store_translations "pt-BR", {}
 
     # Ensure original are still the same since we are reindexing view paths
     assert_equal ORIGINAL_LOCALES, I18n.available_locales.map(&:to_s).sort
@@ -27,121 +29,132 @@ module RenderTestCases
 
   def test_render_without_options
     e = assert_raises(ArgumentError) { @view.render() }
-    assert_match(/You invoked render but did not give any of (.+) option./, e.message)
+    assert_match(/You invoked render but did not give any of (.+) option\./, e.message)
   end
 
   def test_render_file
-    assert_equal "Hello world!", @view.render(:file => "test/hello_world")
+    assert_equal "Hello world!", @view.render(file: "test/hello_world")
   end
 
   # Test if :formats, :locale etc. options are passed correctly to the resolvers.
   def test_render_file_with_format
-    assert_match "<h1>No Comment</h1>", @view.render(:file => "comments/empty", :formats => [:html])
-    assert_match "<error>No Comment</error>", @view.render(:file => "comments/empty", :formats => [:xml])
-    assert_match "<error>No Comment</error>", @view.render(:file => "comments/empty", :formats => :xml)
+    assert_match "<h1>No Comment</h1>", @view.render(file: "comments/empty", formats: [:html])
+    assert_match "<error>No Comment</error>", @view.render(file: "comments/empty", formats: [:xml])
+    assert_match "<error>No Comment</error>", @view.render(file: "comments/empty", formats: :xml)
   end
 
   def test_render_template_with_format
-    assert_match "<h1>No Comment</h1>", @view.render(:template => "comments/empty", :formats => [:html])
-    assert_match "<error>No Comment</error>", @view.render(:template => "comments/empty", :formats => [:xml])
+    assert_match "<h1>No Comment</h1>", @view.render(template: "comments/empty", formats: [:html])
+    assert_match "<error>No Comment</error>", @view.render(template: "comments/empty", formats: [:xml])
   end
 
   def test_rendered_format_without_format
-    @view.render(:inline => "test")
+    @view.render(inline: "test")
     assert_equal :html, @view.lookup_context.rendered_format
   end
 
   def test_render_partial_implicitly_use_format_of_the_rendered_template
     @view.lookup_context.formats = [:json]
-    assert_equal "Hello world", @view.render(:template => "test/one", :formats => [:html])
+    assert_equal "Hello world", @view.render(template: "test/one", formats: [:html])
   end
 
   def test_render_partial_implicitly_use_format_of_the_rendered_partial
     @view.lookup_context.formats = [:html]
-    assert_equal "Third level", @view.render(:template => "test/html_template")
+    assert_equal "Third level", @view.render(template: "test/html_template")
   end
 
   def test_render_partial_use_last_prepended_format_for_partials_with_the_same_names
     @view.lookup_context.formats = [:html]
-    assert_equal "\nHTML Template, but JSON partial", @view.render(:template => "test/change_priority")
+    assert_equal "\nHTML Template, but JSON partial", @view.render(template: "test/change_priority")
   end
 
   def test_render_template_with_a_missing_partial_of_another_format
     @view.lookup_context.formats = [:html]
     e = assert_raise ActionView::Template::Error do
-      @view.render(:template => "with_format", :formats => [:json])
+      @view.render(template: "with_format", formats: [:json])
     end
     assert_includes(e.message, "Missing partial /_missing with {:locale=>[:en], :formats=>[:json], :variants=>[], :handlers=>[:raw, :erb, :html, :builder, :ruby]}.")
   end
 
   def test_render_file_with_locale
-    assert_equal "<h1>Kein Kommentar</h1>", @view.render(:file => "comments/empty", :locale => [:de])
-    assert_equal "<h1>Kein Kommentar</h1>", @view.render(:file => "comments/empty", :locale => :de)
+    assert_equal "<h1>Kein Kommentar</h1>", @view.render(file: "comments/empty", locale: [:de])
+    assert_equal "<h1>Kein Kommentar</h1>", @view.render(file: "comments/empty", locale: :de)
   end
 
   def test_render_template_with_locale
-    assert_equal "<h1>Kein Kommentar</h1>", @view.render(:template => "comments/empty", :locale => [:de])
+    assert_equal "<h1>Kein Kommentar</h1>", @view.render(template: "comments/empty", locale: [:de])
+  end
+
+  def test_render_template_with_variants
+    assert_equal "<h1>No Comment</h1>\n", @view.render(template: "comments/empty", variants: :grid)
   end
 
   def test_render_file_with_handlers
-    assert_equal "<h1>No Comment</h1>\n", @view.render(:file => "comments/empty", :handlers => [:builder])
-    assert_equal "<h1>No Comment</h1>\n", @view.render(:file => "comments/empty", :handlers => :builder)
+    assert_equal "<h1>No Comment</h1>\n", @view.render(file: "comments/empty", handlers: [:builder])
+    assert_equal "<h1>No Comment</h1>\n", @view.render(file: "comments/empty", handlers: :builder)
   end
 
   def test_render_template_with_handlers
-    assert_equal "<h1>No Comment</h1>\n", @view.render(:template => "comments/empty", :handlers => [:builder])
+    assert_equal "<h1>No Comment</h1>\n", @view.render(template: "comments/empty", handlers: [:builder])
   end
 
   def test_render_raw_template_with_handlers
-    assert_equal "<%= hello_world %>\n", @view.render(:template => "plain_text")
+    assert_equal "<%= hello_world %>\n", @view.render(template: "plain_text")
   end
 
   def test_render_raw_template_with_quotes
-    assert_equal %q;Here are some characters: !@#$%^&*()-="'}{`; + "\n", @view.render(:template => "plain_text_with_characters")
+    assert_equal %q;Here are some characters: !@#$%^&*()-="'}{`; + "\n", @view.render(template: "plain_text_with_characters")
+  end
+
+  def test_render_raw_is_html_safe_and_does_not_escape_output
+    buffer = ActiveSupport::SafeBuffer.new
+    buffer << @view.render(file: "plain_text")
+    assert_equal true, buffer.html_safe?
+    assert_equal buffer, "<%= hello_world %>\n"
   end
 
   def test_render_ruby_template_with_handlers
-    assert_equal "Hello from Ruby code", @view.render(:template => "ruby_template")
+    assert_equal "Hello from Ruby code", @view.render(template: "ruby_template")
   end
 
   def test_render_ruby_template_inline
-    assert_equal '4', @view.render(:inline => "(2**2).to_s", :type => :ruby)
+    assert_equal "4", @view.render(inline: "(2**2).to_s", type: :ruby)
   end
 
   def test_render_file_with_localization_on_context_level
     old_locale, @view.locale = @view.locale, :da
-    assert_equal "Hey verden", @view.render(:file => "test/hello_world")
+    assert_equal "Hey verden", @view.render(file: "test/hello_world")
   ensure
     @view.locale = old_locale
   end
 
   def test_render_file_with_dashed_locale
     old_locale, @view.locale = @view.locale, :"pt-BR"
-    assert_equal "Ola mundo", @view.render(:file => "test/hello_world")
+    assert_equal "Ola mundo", @view.render(file: "test/hello_world")
   ensure
     @view.locale = old_locale
   end
 
   def test_render_file_at_top_level
-    assert_equal 'Elastica', @view.render(:file => '/shared')
+    assert_equal "Elastica", @view.render(file: "/shared")
   end
 
   def test_render_file_with_full_path
-    template_path = File.join(File.dirname(__FILE__), '../fixtures/test/hello_world')
-    assert_equal "Hello world!", @view.render(:file => template_path)
+    template_path = File.expand_path("../fixtures/test/hello_world", __dir__)
+    assert_equal "Hello world!", @view.render(file: template_path)
   end
 
   def test_render_file_with_instance_variables
-    assert_equal "The secret is in the sauce\n", @view.render(:file => "test/render_file_with_ivar")
+    assert_equal "The secret is in the sauce\n", @view.render(file: "test/render_file_with_ivar")
   end
 
   def test_render_file_with_locals
-    locals = { :secret => 'in the sauce' }
-    assert_equal "The secret is in the sauce\n", @view.render(:file => "test/render_file_with_locals", :locals => locals)
+    locals = { secret: "in the sauce" }
+    assert_equal "The secret is in the sauce\n", @view.render(file: "test/render_file_with_locals", locals: locals)
   end
 
   def test_render_file_not_using_full_path_with_dot_in_path
-    assert_equal "The secret is in the sauce\n", @view.render(:file => "test/dot.directory/render_file_with_ivar")
+    assert_equal "The secret is in the sauce\n", @view.render(file: "test/dot.directory/render_file_with_ivar")
   end
 
   def test_render_partial_from_default
@@ -149,84 +162,88 @@ module RenderTestCases
   end
 
   def test_render_outside_path
-    assert File.exist?(File.join(File.dirname(__FILE__), '../../test/abstract_unit.rb'))
+    assert File.exist?(File.expand_path("../../test/abstract_unit.rb", __dir__))
     assert_raises ActionView::MissingTemplate do
-      @view.render(:template => "../\\../test/abstract_unit.rb")
+      @view.render(template: "../\\../test/abstract_unit.rb")
     end
   end
 
   def test_render_partial
-    assert_equal "only partial", @view.render(:partial => "test/partial_only")
+    assert_equal "only partial", @view.render(partial: "test/partial_only")
   end
 
   def test_render_partial_with_format
-    assert_equal 'partial html', @view.render(:partial => 'test/partial')
+    assert_equal "partial html", @view.render(partial: "test/partial")
+  end
+
+  def test_render_partial_with_variants
+    assert_equal "<h1>Partial with variants</h1>\n", @view.render(partial: "test/partial_with_variants", variants: :grid)
   end
 
   def test_render_partial_with_selected_format
-    assert_equal 'partial html', @view.render(:partial => 'test/partial', :formats => :html)
-    assert_equal 'partial js', @view.render(:partial => 'test/partial', :formats => [:js])
+    assert_equal "partial html", @view.render(partial: "test/partial", formats: :html)
+    assert_equal "partial js", @view.render(partial: "test/partial", formats: [:js])
   end
 
   def test_render_partial_at_top_level
     # file fixtures/_top_level_partial_only (not fixtures/test)
-    assert_equal 'top level partial', @view.render(:partial => '/top_level_partial_only')
+    assert_equal "top level partial", @view.render(partial: "/top_level_partial_only")
   end
 
   def test_render_partial_with_format_at_top_level
     # file fixtures/_top_level_partial.html (not fixtures/test, with format extension)
-    assert_equal 'top level partial html', @view.render(:partial => '/top_level_partial')
+    assert_equal "top level partial html", @view.render(partial: "/top_level_partial")
   end
 
   def test_render_partial_with_locals
-    assert_equal "5", @view.render(:partial => "test/counter", :locals => { :counter_counter => 5 })
+    assert_equal "5", @view.render(partial: "test/counter", locals: { counter_counter: 5 })
   end
 
   def test_render_partial_with_locals_from_default
-    assert_equal "only partial", @view.render("test/partial_only", :counter_counter => 5)
+    assert_equal "only partial", @view.render("test/partial_only", counter_counter: 5)
   end
 
   def test_render_partial_with_number
-    assert_nothing_raised { @view.render(:partial => "test/200") }
+    assert_nothing_raised { @view.render(partial: "test/200") }
   end
 
   def test_render_partial_with_missing_filename
-    assert_raises(ActionView::MissingTemplate) { @view.render(:partial => "test/") }
+    assert_raises(ActionView::MissingTemplate) { @view.render(partial: "test/") }
   end
 
   def test_render_partial_with_incompatible_object
-    e = assert_raises(ArgumentError) { @view.render(:partial => nil) }
+    e = assert_raises(ArgumentError) { @view.render(partial: nil) }
     assert_equal "'#{nil.inspect}' is not an ActiveModel-compatible object. It must implement :to_partial_path.", e.message
   end
 
   def test_render_partial_starting_with_a_capital
-    assert_nothing_raised { @view.render(:partial => 'test/FooBar') }
+    assert_nothing_raised { @view.render(partial: "test/FooBar") }
   end
 
   def test_render_partial_with_hyphen
-    assert_nothing_raised { @view.render(:partial => "test/a-in") }
+    assert_nothing_raised { @view.render(partial: "test/a-in") }
   end
 
   def test_render_partial_with_unicode_text
-    assert_nothing_raised { @view.render(:partial => "test/🍣") }
+    assert_nothing_raised { @view.render(partial: "test/🍣") }
   end
 
   def test_render_partial_with_invalid_option_as
-    e = assert_raises(ArgumentError) { @view.render(:partial => "test/partial_only", :as => 'a-in') }
-    assert_equal "The value (a-in) of the option `as` is not a valid Ruby identifier; " +
-      "make sure it starts with lowercase letter, " +
+    e = assert_raises(ArgumentError) { @view.render(partial: "test/partial_only", as: "a-in") }
+    assert_equal "The value (a-in) of the option `as` is not a valid Ruby identifier; " \
+      "make sure it starts with lowercase letter, " \
       "and is followed by any combination of letters, numbers and underscores.", e.message
   end
 
   def test_render_partial_with_hyphen_and_invalid_option_as
-    e = assert_raises(ArgumentError) { @view.render(:partial => "test/a-in", :as => 'a-in') }
-    assert_equal "The value (a-in) of the option `as` is not a valid Ruby identifier; " +
-      "make sure it starts with lowercase letter, " +
+    e = assert_raises(ArgumentError) { @view.render(partial: "test/a-in", as: "a-in") }
+    assert_equal "The value (a-in) of the option `as` is not a valid Ruby identifier; " \
+      "make sure it starts with lowercase letter, " \
       "and is followed by any combination of letters, numbers and underscores.", e.message
   end
 
   def test_render_partial_with_errors
-    e = assert_raises(ActionView::Template::Error) { @view.render(:partial => "test/raise") }
+    e = assert_raises(ActionView::Template::Error) { @view.render(partial: "test/raise") }
     assert_match %r!method.*doesnt_exist!, e.message
     assert_equal "", e.sub_template_message
     assert_equal "1", e.line_number
@@ -235,7 +252,7 @@ module RenderTestCases
   end
 
   def test_render_error_indentation
-    e = assert_raises(ActionView::Template::Error) { @view.render(:partial => "test/raise_indentation") }
+    e = assert_raises(ActionView::Template::Error) { @view.render(partial: "test/raise_indentation") }
     error_lines = e.annoted_source_code
     assert_match %r!error\shere!, e.message
     assert_equal "11", e.line_number
@@ -244,15 +261,15 @@ module RenderTestCases
   end
 
   def test_render_sub_template_with_errors
-    e = assert_raises(ActionView::Template::Error) { @view.render(:template => "test/sub_template_raise") }
+    e = assert_raises(ActionView::Template::Error) { @view.render(template: "test/sub_template_raise") }
     assert_match %r!method.*doesnt_exist!, e.message
-    assert_equal "Trace of template inclusion: #{File.expand_path("#{FIXTURE_LOAD_PATH}/test/sub_template_raise.html.erb")}", e.sub_template_message
+    assert_match %r{Trace of template inclusion: .*test/sub_template_raise\.html\.erb}, e.sub_template_message
     assert_equal "1", e.line_number
     assert_equal File.expand_path("#{FIXTURE_LOAD_PATH}/test/_raise.html.erb"), e.file_name
   end
 
   def test_render_file_with_errors
-    e = assert_raises(ActionView::Template::Error) { @view.render(:file => File.expand_path("test/_raise", FIXTURE_LOAD_PATH)) }
+    e = assert_raises(ActionView::Template::Error) { @view.render(file: File.expand_path("test/_raise", FIXTURE_LOAD_PATH)) }
     assert_match %r!method.*doesnt_exist!, e.message
     assert_equal "", e.sub_template_message
     assert_equal "1", e.line_number
@@ -261,109 +278,126 @@ module RenderTestCases
   end
 
   def test_render_object
-    assert_equal "Hello: david", @view.render(:partial => "test/customer", :object => Customer.new("david"))
-    assert_equal "FalseClass", @view.render(:partial => "test/klass", :object => false)
-    assert_equal "NilClass", @view.render(:partial => "test/klass", :object => nil)
+    assert_equal "Hello: david", @view.render(partial: "test/customer", object: Customer.new("david"))
+    assert_equal "FalseClass", @view.render(partial: "test/klass", object: false)
+    assert_equal "NilClass", @view.render(partial: "test/klass", object: nil)
   end
 
   def test_render_object_with_array
-    assert_equal "[1, 2, 3]", @view.render(:partial => "test/object_inspector", :object => [1, 2, 3])
+    assert_equal "[1, 2, 3]", @view.render(partial: "test/object_inspector", object: [1, 2, 3])
   end
 
   def test_render_partial_collection
-    assert_equal "Hello: davidHello: mary", @view.render(:partial => "test/customer", :collection => [ Customer.new("david"), Customer.new("mary") ])
+    assert_equal "Hello: davidHello: mary", @view.render(partial: "test/customer", collection: [ Customer.new("david"), Customer.new("mary") ])
   end
 
   def test_render_partial_collection_with_partial_name_containing_dot
     assert_equal "Hello: davidHello: mary",
-      @view.render(:partial => "test/customer.mobile", :collection => [ Customer.new("david"), Customer.new("mary") ])
+      @view.render(partial: "test/customer.mobile", collection: [ Customer.new("david"), Customer.new("mary") ])
   end
 
   def test_render_partial_collection_as_by_string
     assert_equal "david david davidmary mary mary",
-      @view.render(:partial => "test/customer_with_var", :collection => [ Customer.new("david"), Customer.new("mary") ], :as => 'customer')
+      @view.render(partial: "test/customer_with_var", collection: [ Customer.new("david"), Customer.new("mary") ], as: "customer")
   end
 
   def test_render_partial_collection_as_by_symbol
     assert_equal "david david davidmary mary mary",
-      @view.render(:partial => "test/customer_with_var", :collection => [ Customer.new("david"), Customer.new("mary") ], :as => :customer)
+      @view.render(partial: "test/customer_with_var", collection: [ Customer.new("david"), Customer.new("mary") ], as: :customer)
   end
 
   def test_render_partial_collection_without_as
     assert_equal "local_inspector,local_inspector_counter,local_inspector_iteration",
-      @view.render(:partial => "test/local_inspector", :collection => [ Customer.new("mary") ])
+      @view.render(partial: "test/local_inspector", collection: [ Customer.new("mary") ])
+  end
+
+  def test_render_partial_collection_with_different_partials_still_provides_partial_iteration
+    a = {}
+    b = {}
+    def a.to_partial_path; "test/partial_iteration_1"; end
+    def b.to_partial_path; "test/partial_iteration_2"; end
+
+    assert_equal "local-variable\nlocal-variable", @controller_view.render([a, b])
   end
 
   def test_render_partial_with_empty_collection_should_return_nil
-    assert_nil @view.render(:partial => "test/customer", :collection => [])
+    assert_nil @view.render(partial: "test/customer", collection: [])
   end
 
   def test_render_partial_with_nil_collection_should_return_nil
-    assert_nil @view.render(:partial => "test/customer", :collection => nil)
+    assert_nil @view.render(partial: "test/customer", collection: nil)
+  end
+
+  def test_render_partial_collection_for_non_array
+    customers = Enumerator.new do |y|
+      y.yield(Customer.new("david"))
+      y.yield(Customer.new("mary"))
+    end
+    assert_equal "Hello: davidHello: mary", @view.render(partial: "test/customer", collection: customers)
   end
 
   def test_render_partial_without_object_does_not_put_partial_name_to_local_assigns
-    assert_equal 'false', @view.render(partial: 'test/partial_name_in_local_assigns')
+    assert_equal "false", @view.render(partial: "test/partial_name_in_local_assigns")
   end
 
   def test_render_partial_with_nil_object_puts_partial_name_to_local_assigns
-    assert_equal 'true', @view.render(partial: 'test/partial_name_in_local_assigns', object: nil)
+    assert_equal "true", @view.render(partial: "test/partial_name_in_local_assigns", object: nil)
   end
 
   def test_render_partial_with_nil_values_in_collection
-    assert_equal "Hello: davidHello: Anonymous", @view.render(:partial => "test/customer", :collection => [ Customer.new("david"), nil ])
+    assert_equal "Hello: davidHello: Anonymous", @view.render(partial: "test/customer", collection: [ Customer.new("david"), nil ])
   end
 
   def test_render_partial_with_layout_using_collection_and_template
-    assert_equal "<b>Hello: Amazon</b><b>Hello: Yahoo</b>", @view.render(:partial => "test/customer", :layout => 'test/b_layout_for_partial', :collection => [ Customer.new("Amazon"), Customer.new("Yahoo") ])
+    assert_equal "<b>Hello: Amazon</b><b>Hello: Yahoo</b>", @view.render(partial: "test/customer", layout: "test/b_layout_for_partial", collection: [ Customer.new("Amazon"), Customer.new("Yahoo") ])
   end
 
   def test_render_partial_with_layout_using_collection_and_template_makes_current_item_available_in_layout
     assert_equal '<b class="amazon">Hello: Amazon</b><b class="yahoo">Hello: Yahoo</b>',
-      @view.render(:partial => "test/customer", :layout => 'test/b_layout_for_partial_with_object', :collection => [ Customer.new("Amazon"), Customer.new("Yahoo") ])
+      @view.render(partial: "test/customer", layout: "test/b_layout_for_partial_with_object", collection: [ Customer.new("Amazon"), Customer.new("Yahoo") ])
   end
 
   def test_render_partial_with_layout_using_collection_and_template_makes_current_item_counter_available_in_layout
     assert_equal '<b data-counter="0">Hello: Amazon</b><b data-counter="1">Hello: Yahoo</b>',
-      @view.render(:partial => "test/customer", :layout => 'test/b_layout_for_partial_with_object_counter', :collection => [ Customer.new("Amazon"), Customer.new("Yahoo") ])
+      @view.render(partial: "test/customer", layout: "test/b_layout_for_partial_with_object_counter", collection: [ Customer.new("Amazon"), Customer.new("Yahoo") ])
   end
 
   def test_render_partial_with_layout_using_object_and_template_makes_object_available_in_layout
     assert_equal '<b class="amazon">Hello: Amazon</b>',
-      @view.render(:partial => "test/customer", :layout => 'test/b_layout_for_partial_with_object', :object => Customer.new("Amazon"))
+      @view.render(partial: "test/customer", layout: "test/b_layout_for_partial_with_object", object: Customer.new("Amazon"))
   end
 
   def test_render_partial_with_empty_array_should_return_nil
-    assert_nil @view.render(:partial => [])
+    assert_nil @view.render(partial: [])
   end
 
   def test_render_partial_using_string
-    assert_equal "Hello: Anonymous", @controller_view.render('customer')
+    assert_equal "Hello: Anonymous", @controller_view.render("customer")
   end
 
   def test_render_partial_with_locals_using_string
-    assert_equal "Hola: david", @controller_view.render('customer_greeting', :greeting => 'Hola', :customer_greeting => Customer.new("david"))
+    assert_equal "Hola: david", @controller_view.render("customer_greeting", greeting: "Hola", customer_greeting: Customer.new("david"))
   end
 
   def test_render_partial_with_object_uses_render_partial_path
     assert_equal "Hello: lifo",
-      @controller_view.render(:partial => Customer.new("lifo"), :locals => {:greeting => "Hello"})
+      @controller_view.render(partial: Customer.new("lifo"), locals: { greeting: "Hello" })
   end
 
   def test_render_partial_with_object_and_format_uses_render_partial_path
     assert_equal "<greeting>Hello</greeting><name>lifo</name>",
-      @controller_view.render(:partial => Customer.new("lifo"), :formats => :xml, :locals => {:greeting => "Hello"})
+      @controller_view.render(partial: Customer.new("lifo"), formats: :xml, locals: { greeting: "Hello" })
   end
 
   def test_render_partial_using_object
     assert_equal "Hello: lifo",
-      @controller_view.render(Customer.new("lifo"), :greeting => "Hello")
+      @controller_view.render(Customer.new("lifo"), greeting: "Hello")
   end
 
   def test_render_partial_using_collection
     customers = [ Customer.new("Amazon"), Customer.new("Yahoo") ]
     assert_equal "Hello: AmazonHello: Yahoo",
-      @controller_view.render(customers, :greeting => "Hello")
+      @controller_view.render(customers, greeting: "Hello")
   end
 
   def test_render_partial_using_collection_without_path
@@ -378,44 +412,42 @@ module RenderTestCases
     assert_equal :partial_name_local_variable, exception.cause.name
   end
 
-  # TODO: The reason for this test is unclear, improve documentation
-  def test_render_partial_and_fallback_to_layout
-    assert_equal "Before (Josh)\n\nAfter", @view.render(:partial => "test/layout_for_partial", :locals => { :name => "Josh" })
+  def test_render_partial_with_no_block_given_to_yield
+    assert_equal "Before (Josh)\n\nAfter", @view.render(partial: "test/layout_for_partial", locals: { name: "Josh" })
   end
 
-  # TODO: The reason for this test is unclear, improve documentation
-  def test_render_missing_xml_partial_and_raise_missing_template
+  def test_render_partial_with_non_existent_format_and_raise_missing_template
     @view.formats = [:xml]
-    assert_raises(ActionView::MissingTemplate) { @view.render(:partial => "test/layout_for_partial") }
+    assert_raises(ActionView::MissingTemplate) { @view.render(partial: "test/layout_for_partial") }
   ensure
     @view.formats = nil
   end
 
   def test_render_layout_with_block_and_other_partial_inside
-    render = @view.render(:layout => "test/layout_with_partial_and_yield") { "Yield!" }
+    render = @view.render(layout: "test/layout_with_partial_and_yield") { "Yield!" }
     assert_equal "Before\npartial html\nYield!\nAfter\n", render
   end
 
   def test_render_inline
-    assert_equal "Hello, World!", @view.render(:inline => "Hello, World!")
+    assert_equal "Hello, World!", @view.render(inline: "Hello, World!")
   end
 
   def test_render_inline_with_locals
-    assert_equal "Hello, Josh!", @view.render(:inline => "Hello, <%= name %>!", :locals => { :name => "Josh" })
+    assert_equal "Hello, Josh!", @view.render(inline: "Hello, <%= name %>!", locals: { name: "Josh" })
   end
 
   def test_render_fallbacks_to_erb_for_unknown_types
-    assert_equal "Hello, World!", @view.render(:inline => "Hello, World!", :type => :bar)
+    assert_equal "Hello, World!", @view.render(inline: "Hello, World!", type: :bar)
   end
 
   CustomHandler = lambda do |template|
-    "@output_buffer = ''\n" +
+    "@output_buffer = ''.dup\n" \
       "@output_buffer << 'source: #{template.source.inspect}'\n"
   end
 
   def test_render_inline_with_render_from_to_proc
     ActionView::Template.register_template_handler :ruby_handler, :source.to_proc
-    assert_equal '3', @view.render(inline: "(1 + 2).to_s", type: :ruby_handler)
+    assert_equal "3", @view.render(inline: "(1 + 2).to_s", type: :ruby_handler)
   ensure
     ActionView::Template.unregister_template_handler :ruby_handler
   end
@@ -435,17 +467,17 @@ module RenderTestCases
   end
 
   def test_render_body
-    assert_equal 'some body', @view.render(body: 'some body')
+    assert_equal "some body", @view.render(body: "some body")
   end
 
   def test_render_plain
-    assert_equal 'some plaintext', @view.render(plain: 'some plaintext')
+    assert_equal "some plaintext", @view.render(plain: "some plaintext")
   end
 
   def test_render_knows_about_types_registered_when_extensions_are_checked_earlier_in_initialization
     ActionView::Template::Handlers.extensions
     ActionView::Template.register_template_handler :foo, CustomHandler
-    assert ActionView::Template::Handlers.extensions.include?(:foo)
+    assert_includes ActionView::Template::Handlers.extensions, :foo
   ensure
     ActionView::Template.unregister_template_handler :foo
   end
@@ -460,57 +492,55 @@ module RenderTestCases
   end
 
   def test_render_ignores_templates_with_malformed_template_handlers
-    ActiveSupport::Deprecation.silence do
-      %w(malformed malformed.erb malformed.html.erb malformed.en.html.erb).each do |name|
-        assert File.exist?(File.expand_path("#{FIXTURE_LOAD_PATH}/test/malformed/#{name}~")), "Malformed file (#{name}~) which should be ignored does not exists"
-        assert_raises(ActionView::MissingTemplate) { @view.render(:file => "test/malformed/#{name}") }
-      end
+    %w(malformed malformed.erb malformed.html.erb malformed.en.html.erb).each do |name|
+      assert File.exist?(File.expand_path("#{FIXTURE_LOAD_PATH}/test/malformed/#{name}~")), "Malformed file (#{name}~) which should be ignored does not exists"
+      assert_raises(ActionView::MissingTemplate) { @view.render(file: "test/malformed/#{name}") }
     end
   end
 
   def test_render_with_layout
     assert_equal %(<title></title>\nHello world!\n),
-      @view.render(:file => "test/hello_world", :layout => "layouts/yield")
+      @view.render(file: "test/hello_world", layout: "layouts/yield")
   end
 
   def test_render_with_layout_which_has_render_inline
     assert_equal %(welcome\nHello world!\n),
-      @view.render(:file => "test/hello_world", :layout => "layouts/yield_with_render_inline_inside")
+      @view.render(file: "test/hello_world", layout: "layouts/yield_with_render_inline_inside")
   end
 
   def test_render_with_layout_which_renders_another_partial
     assert_equal %(partial html\nHello world!\n),
-      @view.render(:file => "test/hello_world", :layout => "layouts/yield_with_render_partial_inside")
+      @view.render(file: "test/hello_world", layout: "layouts/yield_with_render_partial_inside")
   end
 
   def test_render_partial_with_html_only_extension
     assert_equal %(<h1>partial html</h1>\nHello world!\n),
-      @view.render(:file => "test/hello_world", :layout => "layouts/render_partial_html")
+      @view.render(file: "test/hello_world", layout: "layouts/render_partial_html")
   end
 
   def test_render_layout_with_block_and_yield
     assert_equal %(Content from block!\n),
-      @view.render(:layout => "layouts/yield_only") { "Content from block!" }
+      @view.render(layout: "layouts/yield_only") { "Content from block!" }
   end
 
   def test_render_layout_with_block_and_yield_with_params
     assert_equal %(Yield! Content from block!\n),
-      @view.render(:layout => "layouts/yield_with_params") { |param| "#{param} Content from block!" }
+      @view.render(layout: "layouts/yield_with_params") { |param| "#{param} Content from block!" }
   end
 
   def test_render_layout_with_block_which_renders_another_partial_and_yields
     assert_equal %(partial html\nContent from block!\n),
-      @view.render(:layout => "layouts/partial_and_yield") { "Content from block!" }
+      @view.render(layout: "layouts/partial_and_yield") { "Content from block!" }
   end
 
   def test_render_partial_and_layout_without_block_with_locals
     assert_equal %(Before (Foo!)\npartial html\nAfter),
-      @view.render(:partial => 'test/partial', :layout => 'test/layout_for_partial', :locals => { :name => 'Foo!'})
+      @view.render(partial: "test/partial", layout: "test/layout_for_partial", locals: { name: "Foo!" })
   end
 
   def test_render_partial_and_layout_without_block_with_locals_and_rendering_another_partial
     assert_equal %(Before (Foo!)\npartial html\npartial with partial\n\nAfter),
-      @view.render(:partial => 'test/partial_with_partial', :layout => 'test/layout_for_partial', :locals => { :name => 'Foo!'})
+      @view.render(partial: "test/partial_with_partial", layout: "test/layout_for_partial", locals: { name: "Foo!" })
   end
 
   def test_render_partial_shortcut_with_block_content
@@ -520,42 +550,42 @@ module RenderTestCases
 
   def test_render_layout_with_a_nested_render_layout_call
     assert_equal %(Before (Foo!)\nBefore (Bar!)\npartial html\nAfter\npartial with layout\n\nAfter),
-      @view.render(:partial => 'test/partial_with_layout', :layout => 'test/layout_for_partial', :locals => { :name => 'Foo!'})
+      @view.render(partial: "test/partial_with_layout", layout: "test/layout_for_partial", locals: { name: "Foo!" })
   end
 
   def test_render_layout_with_a_nested_render_layout_call_using_block_with_render_partial
     assert_equal %(Before (Foo!)\nBefore (Bar!)\n\n  partial html\n\nAfterpartial with layout\n\nAfter),
-      @view.render(:partial => 'test/partial_with_layout_block_partial', :layout => 'test/layout_for_partial', :locals => { :name => 'Foo!'})
+      @view.render(partial: "test/partial_with_layout_block_partial", layout: "test/layout_for_partial", locals: { name: "Foo!" })
   end
 
   def test_render_layout_with_a_nested_render_layout_call_using_block_with_render_content
     assert_equal %(Before (Foo!)\nBefore (Bar!)\n\n  Content from inside layout!\n\nAfterpartial with layout\n\nAfter),
-      @view.render(:partial => 'test/partial_with_layout_block_content', :layout => 'test/layout_for_partial', :locals => { :name => 'Foo!'})
+      @view.render(partial: "test/partial_with_layout_block_content", layout: "test/layout_for_partial", locals: { name: "Foo!" })
   end
 
   def test_render_partial_with_layout_raises_descriptive_error
-    e = assert_raises(ActionView::MissingTemplate) { @view.render(partial: 'test/partial', layout: true) }
+    e = assert_raises(ActionView::MissingTemplate) { @view.render(partial: "test/partial", layout: true) }
     assert_match "Missing partial /_true with", e.message
   end
 
   def test_render_with_nested_layout
     assert_equal %(<title>title</title>\n\n<div id="column">column</div>\n<div id="content">content</div>\n),
-      @view.render(:file => "test/nested_layout", :layout => "layouts/yield")
+      @view.render(file: "test/nested_layout", layout: "layouts/yield")
   end
 
   def test_render_with_file_in_layout
     assert_equal %(\n<title>title</title>\n\n),
-      @view.render(:file => "test/layout_render_file")
+      @view.render(file: "test/layout_render_file")
   end
 
   def test_render_layout_with_object
     assert_equal %(<title>David</title>),
-      @view.render(:file => "test/layout_render_object")
+      @view.render(file: "test/layout_render_object")
   end
 
   def test_render_with_passing_couple_extensions_to_one_register_template_handler_function_call
     ActionView::Template.register_template_handler :foo1, :foo2, CustomHandler
-    assert_equal @view.render(inline: "Hello, World!", type: :foo1), @view.render(inline: "Hello, World!", type: :foo2)
+    assert_equal @view.render(inline: "Hello, World!".dup, type: :foo1), @view.render(inline: "Hello, World!".dup, type: :foo2)
   ensure
     ActionView::Template.unregister_template_handler :foo1, :foo2
   end
@@ -600,7 +630,7 @@ class LazyViewRenderTest < ActiveSupport::TestCase
 
   def test_render_utf8_template_with_magic_comment
     with_external_encoding Encoding::ASCII_8BIT do
-      result = @view.render(:file => "test/utf8_magic", :formats => [:html], :layouts => "layouts/yield")
+      result = @view.render(file: "test/utf8_magic", formats: [:html], layouts: "layouts/yield")
       assert_equal Encoding::UTF_8, result.encoding
       assert_equal "\nРусский \nтекст\n\nUTF-8\nUTF-8\nUTF-8\n", result
     end
@@ -608,7 +638,7 @@ class LazyViewRenderTest < ActiveSupport::TestCase
 
   def test_render_utf8_template_with_default_external_encoding
     with_external_encoding Encoding::UTF_8 do
-      result = @view.render(:file => "test/utf8", :formats => [:html], :layouts => "layouts/yield")
+      result = @view.render(file: "test/utf8", formats: [:html], layouts: "layouts/yield")
       assert_equal Encoding::UTF_8, result.encoding
       assert_equal "Русский текст\n\nUTF-8\nUTF-8\nUTF-8\n", result
     end
@@ -616,15 +646,15 @@ class LazyViewRenderTest < ActiveSupport::TestCase
 
   def test_render_utf8_template_with_incompatible_external_encoding
     with_external_encoding Encoding::SHIFT_JIS do
-      e = assert_raises(ActionView::Template::Error) { @view.render(:file => "test/utf8", :formats => [:html], :layouts => "layouts/yield") }
-      assert_match 'Your template was not saved as valid Shift_JIS', e.cause.message
+      e = assert_raises(ActionView::Template::Error) { @view.render(file: "test/utf8", formats: [:html], layouts: "layouts/yield") }
+      assert_match "Your template was not saved as valid Shift_JIS", e.cause.message
     end
   end
 
   def test_render_utf8_template_with_partial_with_incompatible_encoding
     with_external_encoding Encoding::SHIFT_JIS do
-      e = assert_raises(ActionView::Template::Error) { @view.render(:file => "test/utf8_magic_with_bare_partial", :formats => [:html], :layouts => "layouts/yield") }
-      assert_match 'Your template was not saved as valid Shift_JIS', e.cause.message
+      e = assert_raises(ActionView::Template::Error) { @view.render(file: "test/utf8_magic_with_bare_partial", formats: [:html], layouts: "layouts/yield") }
+      assert_match "Your template was not saved as valid Shift_JIS", e.cause.message
     end
   end
 
@@ -661,7 +691,7 @@ class CachedCollectionViewRenderTest < ActiveSupport::TestCase
     customer = Customer.new("david", 1)
     key = cache_key(customer, "test/_customer")
 
-    ActionView::PartialRenderer.collection_cache.write(key, 'Cached')
+    ActionView::PartialRenderer.collection_cache.write(key, "Cached")
 
     assert_not_equal "Cached",
       @view.render(partial: "test/customer", collection: [customer])
@@ -671,7 +701,7 @@ class CachedCollectionViewRenderTest < ActiveSupport::TestCase
     customer = Customer.new("david", 1)
     key = cache_key(customer, "test/_customer")
 
-    ActionView::PartialRenderer.collection_cache.write(key, 'Cached')
+    ActionView::PartialRenderer.collection_cache.write(key, "Cached")
 
     assert_equal "Cached",
       @view.render(partial: "test/customer", collection: [customer], cached: true)
@@ -681,7 +711,7 @@ class CachedCollectionViewRenderTest < ActiveSupport::TestCase
     customer = CachedCustomer.new("david", 1)
     key = cache_key(customer, "test/_cached_customer")
 
-    ActionView::PartialRenderer.collection_cache.write(key, 'Cached')
+    ActionView::PartialRenderer.collection_cache.write(key, "Cached")
 
     assert_equal "Cached",
       @view.render(partial: "test/cached_customer", collection: [customer], cached: true)
@@ -690,6 +720,6 @@ class CachedCollectionViewRenderTest < ActiveSupport::TestCase
   private
     def cache_key(*names, virtual_path)
       digest = ActionView::Digestor.digest name: virtual_path, finder: @view.lookup_context, dependencies: []
-      @view.fragment_cache_key([ *names, digest ])
+      @view.combined_fragment_cache_key([ "#{virtual_path}:#{digest}", *names ])
     end
 end
diff --git a/actionview/test/template/resolver_cache_test.rb b/actionview/test/template/resolver_cache_test.rb
index 1081c13db0..8a5db1346a 100644
--- a/actionview/test/template/resolver_cache_test.rb
+++ b/actionview/test/template/resolver_cache_test.rb
@@ -1,4 +1,6 @@
-require 'abstract_unit'
+# frozen_string_literal: true
+
+require "abstract_unit"
 
 class ResolverCacheTest < ActiveSupport::TestCase
   def test_inspect_shields_cache_internals
diff --git a/actionview/test/template/resolver_patterns_test.rb b/actionview/test/template/resolver_patterns_test.rb
index 1a091bd692..1e1a4c5063 100644
--- a/actionview/test/template/resolver_patterns_test.rb
+++ b/actionview/test/template/resolver_patterns_test.rb
@@ -1,19 +1,21 @@
-require 'abstract_unit'
+# frozen_string_literal: true
+
+require "abstract_unit"
 
 class ResolverPatternsTest < ActiveSupport::TestCase
   def setup
-    path = File.expand_path("../../fixtures/", __FILE__)
+    path = File.expand_path("../fixtures", __dir__)
     pattern = ":prefix/{:formats/,}:action{.:formats,}{+:variants,}{.:handlers,}"
     @resolver = ActionView::FileSystemResolver.new(path, pattern)
   end
 
   def test_should_return_empty_list_for_unknown_path
-    templates = @resolver.find_all("unknown", "custom_pattern", false, {locale: [], formats: [:html], variants: [], handlers: [:erb]})
+    templates = @resolver.find_all("unknown", "custom_pattern", false, locale: [], formats: [:html], variants: [], handlers: [:erb])
     assert_equal [], templates, "expected an empty list of templates"
   end
 
   def test_should_return_template_for_declared_path
-    templates = @resolver.find_all("path", "custom_pattern", false, {locale: [], formats: [:html], variants: [], handlers: [:erb]})
+    templates = @resolver.find_all("path", "custom_pattern", false, locale: [], formats: [:html], variants: [], handlers: [:erb])
     assert_equal 1, templates.size, "expected one template"
     assert_equal "Hello custom patterns!", templates.first.source
     assert_equal "custom_pattern/path",    templates.first.virtual_path
@@ -21,7 +23,7 @@ class ResolverPatternsTest < ActiveSupport::TestCase
   end
 
   def test_should_return_all_templates_when_ambiguous_pattern
-    templates = @resolver.find_all("another", "custom_pattern", false, {locale: [], formats: [:html], variants: [], handlers: [:erb]})
+    templates = @resolver.find_all("another", "custom_pattern", false, locale: [], formats: [:html], variants: [], handlers: [:erb])
     assert_equal 2, templates.size, "expected two templates"
     assert_equal "Another template!",      templates[0].source
     assert_equal "custom_pattern/another", templates[0].virtual_path
@@ -30,7 +32,7 @@ class ResolverPatternsTest < ActiveSupport::TestCase
   end
 
   def test_should_return_all_variants_for_any
-    templates = @resolver.find_all("hello_world", "test", false, {locale: [], formats: [:html, :text], variants: :any, handlers: [:erb]})
+    templates = @resolver.find_all("hello_world", "test", false, locale: [], formats: [:html, :text], variants: :any, handlers: [:erb])
     assert_equal 3, templates.size, "expected three templates"
     assert_equal "Hello phone!",       templates[0].source
     assert_equal "test/hello_world",   templates[0].virtual_path
diff --git a/actionview/test/template/sanitize_helper_test.rb b/actionview/test/template/sanitize_helper_test.rb
index efe846a7eb..0e690c82cb 100644
--- a/actionview/test/template/sanitize_helper_test.rb
+++ b/actionview/test/template/sanitize_helper_test.rb
@@ -1,6 +1,8 @@
-require 'abstract_unit'
+# frozen_string_literal: true
 
-# The exhaustive tests are in test/controller/html/sanitizer_test.rb.
+require "abstract_unit"
+
+# The exhaustive tests are in the rails-html-sanitizer gem.
 # This tests that the helpers hook up correctly to the sanitizer classes.
 class SanitizeHelperTest < ActionView::TestCase
   tests ActionView::Helpers::SanitizeHelper
@@ -10,22 +12,24 @@ class SanitizeHelperTest < ActionView::TestCase
     assert_equal "on my mind\nall day long", strip_links("<a href='almost'>on my mind</a>\n<A href='almost'>all day long</A>")
     assert_equal "Magic", strip_links("<a href='http://www.rubyonrails.com/'>Mag<a href='http://www.ruby-lang.org/'>ic")
     assert_equal "My mind\nall <b>day</b> long", strip_links("<a href='almost'>My mind</a>\n<A href='almost'>all <b>day</b> long</A>")
+    assert_equal "&lt;malformed &amp; link", strip_links('<<a href="https://example.org">malformed & link</a>')
   end
 
   def test_sanitize_form
-    assert_equal '', sanitize("<form action=\"/foo/bar\" method=\"post\"><input></form>")
+    assert_equal "", sanitize("<form action=\"/foo/bar\" method=\"post\"><input></form>")
   end
 
   def test_should_sanitize_illegal_style_properties
     raw      = %(display:block; position:absolute; left:0; top:0; width:100%; height:100%; z-index:1; background-color:black; background-image:url(http://www.ragingplatypus.com/i/cam-full.jpg); background-x:center; background-y:center; background-repeat:repeat;)
-    expected = %(display: block; width: 100%; height: 100%; background-color: black; background-x: center; background-y: center;)
-    assert_equal expected, sanitize_css(raw)
+    expected = %r(\Adisplay:\s?block;\s?width:\s?100%;\s?height:\s?100%;\s?background-color:\s?black;\s?background-x:\s?center;\s?background-y:\s?center;\z)
+    assert_match expected, sanitize_css(raw)
   end
 
   def test_strip_tags
     assert_equal("Dont touch me", strip_tags("Dont touch me"))
     assert_equal("This is a test.", strip_tags("<p>This <u>is<u> a <a href='test.html'><strong>test</strong></a>.</p>"))
     assert_equal "This has a  here.", strip_tags("This has a <!-- comment --> here.")
+    assert_equal("Jekyll &amp; Hyde", strip_tags("Jekyll & Hyde"))
     assert_equal "", strip_tags("<script>")
   end
 
diff --git a/actionview/test/template/streaming_render_test.rb b/actionview/test/template/streaming_render_test.rb
index d06ba4ceb0..ef000300cc 100644
--- a/actionview/test/template/streaming_render_test.rb
+++ b/actionview/test/template/streaming_render_test.rb
@@ -1,12 +1,14 @@
-require 'abstract_unit'
+# frozen_string_literal: true
+
+require "abstract_unit"
 
 class TestController < ActionController::Base
 end
 
-class FiberedTest < ActiveSupport::TestCase
+class SetupFiberedBase < ActiveSupport::TestCase
   def setup
     view_paths = ActionController::Base.view_paths
-    @assigns = { :secret => 'in the sauce', :name => nil }
+    @assigns = { secret: "in the sauce", name: nil }
     @view = ActionView::Base.new(view_paths, @assigns)
     @controller_view = TestController.new.view_context
   end
@@ -17,16 +19,18 @@ class FiberedTest < ActiveSupport::TestCase
 
   def buffered_render(options)
     body = render_body(options)
-    string = ""
+    string = "".dup
     body.each do |piece|
       string << piece
     end
     string
   end
+end
 
+class FiberedTest < SetupFiberedBase
   def test_streaming_works
     content = []
-    body = render_body(:template => "test/hello_world", :layout => "layouts/yield")
+    body = render_body(template: "test/hello_world", layout: "layouts/yield")
 
     body.each do |piece|
       content << piece
@@ -40,68 +44,68 @@ class FiberedTest < ActiveSupport::TestCase
   end
 
   def test_render_file
-    assert_equal "Hello world!", buffered_render(:file => "test/hello_world")
+    assert_equal "Hello world!", buffered_render(file: "test/hello_world")
   end
 
   def test_render_file_with_locals
-    locals = { :secret => 'in the sauce' }
-    assert_equal "The secret is in the sauce\n", buffered_render(:file => "test/render_file_with_locals", :locals => locals)
+    locals = { secret: "in the sauce" }
+    assert_equal "The secret is in the sauce\n", buffered_render(file: "test/render_file_with_locals", locals: locals)
   end
 
   def test_render_partial
-    assert_equal "only partial", buffered_render(:partial => "test/partial_only")
+    assert_equal "only partial", buffered_render(partial: "test/partial_only")
   end
 
   def test_render_inline
-    assert_equal "Hello, World!", buffered_render(:inline => "Hello, World!")
+    assert_equal "Hello, World!", buffered_render(inline: "Hello, World!")
   end
 
   def test_render_without_layout
-    assert_equal "Hello world!", buffered_render(:template => "test/hello_world")
+    assert_equal "Hello world!", buffered_render(template: "test/hello_world")
   end
 
   def test_render_with_layout
     assert_equal %(<title></title>\nHello world!\n),
-      buffered_render(:template => "test/hello_world", :layout => "layouts/yield")
+      buffered_render(template: "test/hello_world", layout: "layouts/yield")
   end
 
   def test_render_with_layout_which_has_render_inline
     assert_equal %(welcome\nHello world!\n),
-      buffered_render(:template => "test/hello_world", :layout => "layouts/yield_with_render_inline_inside")
+      buffered_render(template: "test/hello_world", layout: "layouts/yield_with_render_inline_inside")
   end
 
   def test_render_with_layout_which_renders_another_partial
     assert_equal %(partial html\nHello world!\n),
-      buffered_render(:template => "test/hello_world", :layout => "layouts/yield_with_render_partial_inside")
+      buffered_render(template: "test/hello_world", layout: "layouts/yield_with_render_partial_inside")
   end
 
   def test_render_with_nested_layout
     assert_equal %(<title>title</title>\n\n<div id="column">column</div>\n<div id="content">content</div>\n),
-      buffered_render(:template => "test/nested_layout", :layout => "layouts/yield")
+      buffered_render(template: "test/nested_layout", layout: "layouts/yield")
   end
 
   def test_render_with_file_in_layout
     assert_equal %(\n<title>title</title>\n\n),
-      buffered_render(:template => "test/layout_render_file")
+      buffered_render(template: "test/layout_render_file")
   end
 
   def test_render_with_handler_without_streaming_support
-    assert_match "<p>This is grand!</p>", buffered_render(:template => "test/hello")
+    assert_match "<p>This is grand!</p>", buffered_render(template: "test/hello")
   end
 
   def test_render_with_streaming_multiple_yields_provide_and_content_for
     assert_equal "Yes, \nthis works\n like a charm.",
-      buffered_render(:template => "test/streaming", :layout => "layouts/streaming")
+      buffered_render(template: "test/streaming", layout: "layouts/streaming")
   end
 
   def test_render_with_streaming_with_fake_yields_and_streaming_buster
     assert_equal "This won't look\n good.",
-      buffered_render(:template => "test/streaming_buster", :layout => "layouts/streaming")
+      buffered_render(template: "test/streaming_buster", layout: "layouts/streaming")
   end
 
   def test_render_with_nested_streaming_multiple_yields_provide_and_content_for
     assert_equal "?Yes, \n\nthis works\n\n? like a charm.",
-      buffered_render(:template => "test/nested_streaming", :layout => "layouts/streaming")
+      buffered_render(template: "test/nested_streaming", layout: "layouts/streaming")
   end
 
   def test_render_with_streaming_and_capture
@@ -109,3 +113,20 @@ class FiberedTest < ActiveSupport::TestCase
       buffered_render(template: "test/streaming", layout: "layouts/streaming_with_capture")
   end
 end
+
+class FiberedWithLocaleTest < SetupFiberedBase
+  def setup
+    @old_locale = I18n.locale
+    I18n.locale = "da"
+    super
+  end
+
+  def teardown
+    I18n.locale = @old_locale
+  end
+
+  def test_render_with_streaming_and_locale
+    assert_equal "layout.locale: da\nview.locale: da\n\n",
+      buffered_render(template: "test/streaming_with_locale", layout: "layouts/streaming_with_locale")
+  end
+end
diff --git a/actionview/test/template/tag_helper_test.rb b/actionview/test/template/tag_helper_test.rb
index f3956a31f6..a746b9c1b5 100644
--- a/actionview/test/template/tag_helper_test.rb
+++ b/actionview/test/template/tag_helper_test.rb
@@ -1,4 +1,6 @@
-require 'abstract_unit'
+# frozen_string_literal: true
+
+require "abstract_unit"
 
 class TagHelperTest < ActionView::TestCase
   include RenderERBUtils
@@ -7,10 +9,28 @@ class TagHelperTest < ActionView::TestCase
 
   def test_tag
     assert_equal "<br />", tag("br")
-    assert_equal "<br clear=\"left\" />", tag(:br, :clear => "left")
+    assert_equal "<br clear=\"left\" />", tag(:br, clear: "left")
     assert_equal "<br>", tag("br", nil, true)
   end
 
+  def test_tag_builder
+    assert_equal "<span></span>", tag.span
+    assert_equal "<span class=\"bookmark\"></span>", tag.span(class: "bookmark")
+  end
+
+  def test_tag_builder_void_tag
+    assert_equal "<br>", tag.br
+    assert_equal "<br class=\"some_class\">", tag.br(class: "some_class")
+  end
+
+  def test_tag_builder_void_tag_with_forced_content
+    assert_equal "<br>some content</br>", tag.br("some content")
+  end
+
+  def test_tag_builder_is_singleton
+    assert_equal tag, tag
+  end
+
   def test_tag_options
     str = tag("p", "class" => "show", :class => "elsewhere")
     assert_match(/class="show"/, str)
@@ -18,31 +38,76 @@ class TagHelperTest < ActionView::TestCase
   end
 
   def test_tag_options_rejects_nil_option
-    assert_equal "<p />", tag("p", :ignored => nil)
+    assert_equal "<p />", tag("p", ignored: nil)
+  end
+
+  def test_tag_builder_options_rejects_nil_option
+    assert_equal "<p></p>", tag.p(ignored: nil)
   end
 
   def test_tag_options_accepts_false_option
-    assert_equal "<p value=\"false\" />", tag("p", :value => false)
+    assert_equal "<p value=\"false\" />", tag("p", value: false)
+  end
+
+  def test_tag_builder_options_accepts_false_option
+    assert_equal "<p value=\"false\"></p>", tag.p(value: false)
   end
 
   def test_tag_options_accepts_blank_option
-    assert_equal "<p included=\"\" />", tag("p", :included => '')
+    assert_equal "<p included=\"\" />", tag("p", included: "")
+  end
+
+  def test_tag_builder_options_accepts_blank_option
+    assert_equal "<p included=\"\"></p>", tag.p(included: "")
+  end
+
+  def test_tag_options_accepts_symbol_option_when_not_escaping
+    assert_equal "<p value=\"symbol\" />", tag("p", { value: :symbol }, false, false)
+  end
+
+  def test_tag_options_accepts_integer_option_when_not_escaping
+    assert_equal "<p value=\"42\" />", tag("p", { value: 42 }, false, false)
   end
 
   def test_tag_options_converts_boolean_option
     assert_dom_equal '<p disabled="disabled" itemscope="itemscope" multiple="multiple" readonly="readonly" allowfullscreen="allowfullscreen" seamless="seamless" typemustmatch="typemustmatch" sortable="sortable" default="default" inert="inert" truespeed="truespeed" />',
-      tag("p", :disabled => true, :itemscope => true, :multiple => true, :readonly => true, :allowfullscreen => true, :seamless => true, :typemustmatch => true, :sortable => true, :default => true, :inert => true, :truespeed => true)
+      tag("p", disabled: true, itemscope: true, multiple: true, readonly: true, allowfullscreen: true, seamless: true, typemustmatch: true, sortable: true, default: true, inert: true, truespeed: true)
+  end
+
+  def test_tag_builder_options_converts_boolean_option
+    assert_dom_equal '<p disabled="disabled" itemscope="itemscope" multiple="multiple" readonly="readonly" allowfullscreen="allowfullscreen" seamless="seamless" typemustmatch="typemustmatch" sortable="sortable" default="default" inert="inert" truespeed="truespeed" />',
+      tag.p(disabled: true, itemscope: true, multiple: true, readonly: true, allowfullscreen: true, seamless: true, typemustmatch: true, sortable: true, default: true, inert: true, truespeed: true)
   end
 
   def test_content_tag
     assert_equal "<a href=\"create\">Create</a>", content_tag("a", "Create", "href" => "create")
     assert content_tag("a", "Create", "href" => "create").html_safe?
     assert_equal content_tag("a", "Create", "href" => "create"),
-                 content_tag("a", "Create", :href => "create")
+                 content_tag("a", "Create", href: "create")
+    assert_equal "<p>&lt;script&gt;evil_js&lt;/script&gt;</p>",
+                 content_tag(:p, "<script>evil_js</script>")
+    assert_equal "<p><script>evil_js</script></p>",
+                 content_tag(:p, "<script>evil_js</script>", nil, false)
+  end
+
+  def test_tag_builder_with_content
+    assert_equal "<div id=\"post_1\">Content</div>", tag.div("Content", id: "post_1")
+    assert tag.div("Content", id: "post_1").html_safe?
+    assert_equal tag.div("Content", id: "post_1"),
+                 tag.div("Content", "id": "post_1")
     assert_equal "<p>&lt;script&gt;evil_js&lt;/script&gt;</p>",
-                 content_tag(:p, '<script>evil_js</script>')
+                 tag.p("<script>evil_js</script>")
     assert_equal "<p><script>evil_js</script></p>",
-                 content_tag(:p, '<script>evil_js</script>', nil, false)
+                 tag.p("<script>evil_js</script>", escape_attributes: false)
+  end
+
+  def test_tag_builder_nested
+    assert_equal "<div>content</div>",
+                 tag.div { "content" }
+    assert_equal "<div id=\"header\"><span>hello</span></div>",
+                 tag.div(id: "header") { |tag| tag.span "hello" }
+    assert_equal "<div id=\"header\"><div class=\"world\"><span>hello</span></div></div>",
+                 tag.div(id: "header") { |tag| tag.div(class: "world") { tag.span "hello" } }
   end
 
   def test_content_tag_with_block_in_erb
@@ -50,72 +115,138 @@ class TagHelperTest < ActionView::TestCase
     assert_dom_equal "<div>Hello world!</div>", buffer
   end
 
+  def test_tag_builder_with_block_in_erb
+    buffer = render_erb("<%= tag.div do %>Hello world!<% end %>")
+    assert_dom_equal "<div>Hello world!</div>", buffer
+  end
+
   def test_content_tag_with_block_in_erb_containing_non_displayed_erb
     buffer = render_erb("<%= content_tag(:p) do %><% 1 %><% end %>")
     assert_dom_equal "<p></p>", buffer
   end
 
+  def test_tag_builder_with_block_in_erb_containing_non_displayed_erb
+    buffer = render_erb("<%= tag.p do %><% 1 %><% end %>")
+    assert_dom_equal "<p></p>", buffer
+  end
+
   def test_content_tag_with_block_and_options_in_erb
     buffer = render_erb("<%= content_tag(:div, :class => 'green') do %>Hello world!<% end %>")
     assert_dom_equal %(<div class="green">Hello world!</div>), buffer
   end
 
+  def test_tag_builder_with_block_and_options_in_erb
+    buffer = render_erb("<%= tag.div(class: 'green') do %>Hello world!<% end %>")
+    assert_dom_equal %(<div class="green">Hello world!</div>), buffer
+  end
+
   def test_content_tag_with_block_and_options_out_of_erb
-    assert_dom_equal %(<div class="green">Hello world!</div>), content_tag(:div, :class => "green") { "Hello world!" }
+    assert_dom_equal %(<div class="green">Hello world!</div>), content_tag(:div, class: "green") { "Hello world!" }
+  end
+
+  def test_tag_builder_with_block_and_options_out_of_erb
+    assert_dom_equal %(<div class="green">Hello world!</div>), tag.div(class: "green") { "Hello world!" }
   end
 
   def test_content_tag_with_block_and_options_outside_out_of_erb
-    assert_equal content_tag("a", "Create", :href => "create"),
+    assert_equal content_tag("a", "Create", href: "create"),
                  content_tag("a", "href" => "create") { "Create" }
   end
 
+  def test_tag_builder_with_block_and_options_outside_out_of_erb
+    assert_equal tag.a("Create", href: "create"),
+                 tag.a("href": "create") { "Create" }
+  end
+
   def test_content_tag_with_block_and_non_string_outside_out_of_erb
     assert_equal content_tag("p"),
                  content_tag("p") { 3.times { "do_something" } }
   end
 
+  def test_tag_builder_with_block_and_non_string_outside_out_of_erb
+    assert_equal tag.p,
+                 tag.p { 3.times { "do_something" } }
+  end
+
   def test_content_tag_nested_in_content_tag_out_of_erb
     assert_equal content_tag("p", content_tag("b", "Hello")),
                  content_tag("p") { content_tag("b", "Hello") },
                  output_buffer
+    assert_equal tag.p(tag.b("Hello")),
+                 tag.p { tag.b("Hello") },
+                 output_buffer
   end
 
   def test_content_tag_nested_in_content_tag_in_erb
     assert_equal "<p>\n  <b>Hello</b>\n</p>", view.render("test/content_tag_nested_in_content_tag")
+    assert_equal "<p>\n  <b>Hello</b>\n</p>", view.render("test/builder_tag_nested_in_content_tag")
   end
 
   def test_content_tag_with_escaped_array_class
-    str = content_tag('p', "limelight", :class => ["song", "play>"])
+    str = content_tag("p", "limelight", class: ["song", "play>"])
+    assert_equal "<p class=\"song play&gt;\">limelight</p>", str
+
+    str = content_tag("p", "limelight", class: ["song", "play"])
+    assert_equal "<p class=\"song play\">limelight</p>", str
+
+    str = content_tag("p", "limelight", class: ["song", ["play"]])
+    assert_equal "<p class=\"song play\">limelight</p>", str
+  end
+
+  def test_tag_builder_with_escaped_array_class
+    str = tag.p "limelight", class: ["song", "play>"]
     assert_equal "<p class=\"song play&gt;\">limelight</p>", str
 
-    str = content_tag('p', "limelight", :class => ["song", "play"])
+    str = tag.p "limelight", class: ["song", "play"]
     assert_equal "<p class=\"song play\">limelight</p>", str
 
-    str = content_tag('p', "limelight", :class => ["song", ["play"]])
+    str = tag.p "limelight", class: ["song", ["play"]]
     assert_equal "<p class=\"song play\">limelight</p>", str
   end
 
   def test_content_tag_with_unescaped_array_class
-    str = content_tag('p', "limelight", {:class => ["song", "play>"]}, false)
+    str = content_tag("p", "limelight", { class: ["song", "play>"] }, false)
     assert_equal "<p class=\"song play>\">limelight</p>", str
 
-    str = content_tag('p', "limelight", {:class => ["song", ["play>"]]}, false)
+    str = content_tag("p", "limelight", { class: ["song", ["play>"]] }, false)
+    assert_equal "<p class=\"song play>\">limelight</p>", str
+  end
+
+  def test_tag_builder_with_unescaped_array_class
+    str = tag.p "limelight", class: ["song", "play>"], escape_attributes: false
+    assert_equal "<p class=\"song play>\">limelight</p>", str
+
+    str = tag.p "limelight", class: ["song", ["play>"]], escape_attributes: false
     assert_equal "<p class=\"song play>\">limelight</p>", str
   end
 
   def test_content_tag_with_empty_array_class
-    str = content_tag('p', 'limelight', {:class => []})
+    str = content_tag("p", "limelight", class: [])
     assert_equal '<p class="">limelight</p>', str
   end
 
+  def test_tag_builder_with_empty_array_class
+    assert_equal '<p class="">limelight</p>', tag.p("limelight", class: [])
+  end
+
   def test_content_tag_with_unescaped_empty_array_class
-    str = content_tag('p', 'limelight', {:class => []}, false)
+    str = content_tag("p", "limelight", { class: [] }, false)
+    assert_equal '<p class="">limelight</p>', str
+  end
+
+  def test_tag_builder_with_unescaped_empty_array_class
+    str = tag.p "limelight", class: [], escape_attributes: false
     assert_equal '<p class="">limelight</p>', str
   end
 
   def test_content_tag_with_data_attributes
     assert_dom_equal '<p data-number="1" data-string="hello" data-string-with-quotes="double&quot;quote&quot;party&quot;">limelight</p>',
-      content_tag('p', "limelight", data: { number: 1, string: 'hello', string_with_quotes: 'double"quote"party"' })
+      content_tag("p", "limelight", data: { number: 1, string: "hello", string_with_quotes: 'double"quote"party"' })
+  end
+
+  def test_tag_builder_with_data_attributes
+    assert_dom_equal '<p data-number="1" data-string="hello" data-string-with-quotes="double&quot;quote&quot;party&quot;">limelight</p>',
+      tag.p("limelight", data: { number: 1, string: "hello", string_with_quotes: 'double"quote"party"' })
   end
 
   def test_cdata_section
@@ -132,51 +263,95 @@ class TagHelperTest < ActionView::TestCase
   end
 
   def test_escape_once
-    assert_equal '1 &lt; 2 &amp; 3', escape_once('1 < 2 &amp; 3')
+    assert_equal "1 &lt; 2 &amp; 3", escape_once("1 < 2 &amp; 3")
     assert_equal " &#X27; &#x27; &#x03BB; &#X03bb; &quot; &#39; &lt; &gt; ", escape_once(" &#X27; &#x27; &#x03BB; &#X03bb; \" ' < > ")
   end
 
   def test_tag_honors_html_safe_for_param_values
-    ['1&amp;2', '1 &lt; 2', '&#8220;test&#8220;'].each do |escaped|
-      assert_equal %(<a href="#{escaped}" />), tag('a', :href => escaped.html_safe)
+    ["1&amp;2", "1 &lt; 2", "&#8220;test&#8220;"].each do |escaped|
+      assert_equal %(<a href="#{escaped}" />), tag("a", href: escaped.html_safe)
+      assert_equal %(<a href="#{escaped}"></a>), tag.a(href: escaped.html_safe)
     end
   end
 
   def test_tag_honors_html_safe_with_escaped_array_class
-    str = tag('p', :class => ['song>', raw('play>')])
-    assert_equal '<p class="song&gt; play>" />', str
+    assert_equal '<p class="song&gt; play>" />', tag("p", class: ["song>", raw("play>")])
+    assert_equal '<p class="song> play&gt;" />', tag("p", class: [raw("song>"), "play>"])
+  end
+
+  def test_tag_builder_honors_html_safe_with_escaped_array_class
+    assert_equal '<p class="song&gt; play>"></p>', tag.p(class: ["song>", raw("play>")])
+    assert_equal '<p class="song> play&gt;"></p>', tag.p(class: [raw("song>"), "play>"])
+  end
+
+  def test_tag_does_not_honor_html_safe_double_quotes_as_attributes
+    assert_dom_equal '<p title="&quot;">content</p>',
+      content_tag("p", "content", title: '"'.html_safe)
+  end
 
-    str = tag('p', :class => [raw('song>'), 'play>'])
-    assert_equal '<p class="song> play&gt;" />', str
+  def test_data_tag_does_not_honor_html_safe_double_quotes_as_attributes
+    assert_dom_equal '<p data-title="&quot;">content</p>',
+      content_tag("p", "content", data: { title: '"'.html_safe })
   end
 
   def test_skip_invalid_escaped_attributes
-    ['&1;', '&#1dfa3;', '& #123;'].each do |escaped|
-      assert_equal %(<a href="#{escaped.gsub(/&/, '&amp;')}" />), tag('a', :href => escaped)
+    ["&1;", "&#1dfa3;", "& #123;"].each do |escaped|
+      assert_equal %(<a href="#{escaped.gsub(/&/, '&amp;')}" />), tag("a", href: escaped)
+      assert_equal %(<a href="#{escaped.gsub(/&/, '&amp;')}"></a>), tag.a(href: escaped)
     end
   end
 
   def test_disable_escaping
-    assert_equal '<a href="&amp;" />', tag('a', { :href => '&amp;' }, false, false)
+    assert_equal '<a href="&amp;" />', tag("a", { href: "&amp;" }, false, false)
+  end
+
+  def test_tag_builder_disable_escaping
+    assert_equal '<a href="&amp;"></a>', tag.a(href: "&amp;", escape_attributes: false)
+    assert_equal '<a href="&amp;">cnt</a>', tag.a(href: "&amp;", escape_attributes: false) { "cnt" }
+    assert_equal '<br data-hidden="&amp;">', tag.br("data-hidden": "&amp;", escape_attributes: false)
+    assert_equal '<a href="&amp;">content</a>', tag.a("content", href: "&amp;", escape_attributes: false)
+    assert_equal '<a href="&amp;">content</a>', tag.a(href: "&amp;", escape_attributes: false) { "content" }
   end
 
   def test_data_attributes
-    ['data', :data].each { |data|
+    ["data", :data].each { |data|
       assert_dom_equal '<a data-a-float="3.14" data-a-big-decimal="-123.456" data-a-number="1" data-array="[1,2,3]" data-hash="{&quot;key&quot;:&quot;value&quot;}" data-string-with-quotes="double&quot;quote&quot;party&quot;" data-string="hello" data-symbol="foo" />',
-        tag('a', { data => { a_float: 3.14, a_big_decimal: BigDecimal.new("-123.456"), a_number: 1, string: 'hello', symbol: :foo, array: [1, 2, 3], hash: { key: 'value'}, string_with_quotes: 'double"quote"party"' } })
+        tag("a", data => { a_float: 3.14, a_big_decimal: BigDecimal("-123.456"), a_number: 1, string: "hello", symbol: :foo, array: [1, 2, 3], hash: { key: "value" }, string_with_quotes: 'double"quote"party"' })
+      assert_dom_equal '<a data-a-float="3.14" data-a-big-decimal="-123.456" data-a-number="1" data-array="[1,2,3]" data-hash="{&quot;key&quot;:&quot;value&quot;}" data-string-with-quotes="double&quot;quote&quot;party&quot;" data-string="hello" data-symbol="foo" />',
+        tag.a(data: { a_float: 3.14, a_big_decimal: BigDecimal("-123.456"), a_number: 1, string: "hello", symbol: :foo, array: [1, 2, 3], hash: { key: "value" }, string_with_quotes: 'double"quote"party"' })
     }
   end
 
   def test_aria_attributes
-    ['aria', :aria].each { |aria|
+    ["aria", :aria].each { |aria|
+      assert_dom_equal '<a aria-a-float="3.14" aria-a-big-decimal="-123.456" aria-a-number="1" aria-array="[1,2,3]" aria-hash="{&quot;key&quot;:&quot;value&quot;}" aria-string-with-quotes="double&quot;quote&quot;party&quot;" aria-string="hello" aria-symbol="foo" />',
+        tag("a", aria => { a_float: 3.14, a_big_decimal: BigDecimal("-123.456"), a_number: 1, string: "hello", symbol: :foo, array: [1, 2, 3], hash: { key: "value" }, string_with_quotes: 'double"quote"party"' })
       assert_dom_equal '<a aria-a-float="3.14" aria-a-big-decimal="-123.456" aria-a-number="1" aria-array="[1,2,3]" aria-hash="{&quot;key&quot;:&quot;value&quot;}" aria-string-with-quotes="double&quot;quote&quot;party&quot;" aria-string="hello" aria-symbol="foo" />',
-        tag('a', { aria => { a_float: 3.14, a_big_decimal: BigDecimal.new("-123.456"), a_number: 1, string: 'hello', symbol: :foo, array: [1, 2, 3], hash: { key: 'value'}, string_with_quotes: 'double"quote"party"' } })
+        tag.a(aria: { a_float: 3.14, a_big_decimal: BigDecimal("-123.456"), a_number: 1, string: "hello", symbol: :foo, array: [1, 2, 3], hash: { key: "value" }, string_with_quotes: 'double"quote"party"' })
     }
   end
 
   def test_link_to_data_nil_equal
-    div_type1 = content_tag(:div, 'test', { 'data-tooltip' => nil })
-    div_type2 = content_tag(:div, 'test', { data: {tooltip: nil} })
-    assert_dom_equal div_type1, div_type2 
+    div_type1 = content_tag(:div, "test", "data-tooltip" => nil)
+    div_type2 = content_tag(:div, "test", data: { tooltip: nil })
+    assert_dom_equal div_type1, div_type2
+  end
+
+  def test_tag_builder_link_to_data_nil_equal
+    div_type1 = tag.div "test", 'data-tooltip': nil
+    div_type2 = tag.div "test", data: { tooltip: nil }
+    assert_dom_equal div_type1, div_type2
+  end
+
+  def test_tag_builder_allow_call_via_method_object
+    assert_equal "<foo></foo>", tag.method(:foo).call
+  end
+
+  def test_tag_builder_dasherize_names
+    assert_equal "<img-slider></img-slider>", tag.img_slider
+  end
+
+  def test_respond_to
+    assert_respond_to tag, :any_tag
   end
 end
diff --git a/actionview/test/template/template_error_test.rb b/actionview/test/template/template_error_test.rb
index 54c1d53b60..c4dc88e4aa 100644
--- a/actionview/test/template/template_error_test.rb
+++ b/actionview/test/template/template_error_test.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require "abstract_unit"
 
 class TemplateErrorTest < ActiveSupport::TestCase
diff --git a/actionview/test/template/template_test.rb b/actionview/test/template/template_test.rb
index 533c1c3219..3dc14e36e0 100644
--- a/actionview/test/template/template_test.rb
+++ b/actionview/test/template/template_test.rb
@@ -1,4 +1,6 @@
 # encoding: US-ASCII
+# frozen_string_literal: true
+
 require "abstract_unit"
 require "logger"
 
@@ -35,7 +37,7 @@ class TestERBTemplate < ActiveSupport::TestCase
         "<%= @virtual_path %>",
         "partial",
         ERBHandler,
-        :virtual_path => "partial"
+        virtual_path: "partial"
       )
     end
 
@@ -53,7 +55,7 @@ class TestERBTemplate < ActiveSupport::TestCase
   end
 
   def new_template(body = "<%= hello %>", details = { format: :html })
-    ActionView::Template.new(body, "hello template", details.fetch(:handler) { ERBHandler }, {:virtual_path => "hello"}.merge!(details))
+    ActionView::Template.new(body.dup, "hello template", details.fetch(:handler) { ERBHandler }, { virtual_path: "hello" }.merge!(details))
   end
 
   def render(locals = {})
@@ -80,7 +82,7 @@ class TestERBTemplate < ActiveSupport::TestCase
   end
 
   def test_raw_template
-    @template = new_template("<%= hello %>", :handler => ActionView::Template::Handlers::Raw.new)
+    @template = new_template("<%= hello %>", handler: ActionView::Template::Handlers::Raw.new)
     assert_equal "<%= hello %>", render
   end
 
@@ -91,7 +93,7 @@ class TestERBTemplate < ActiveSupport::TestCase
   end
 
   def test_template_does_not_lose_its_source_after_rendering_if_it_does_not_have_a_virtual_path
-    @template = new_template("Hello", :virtual_path => nil)
+    @template = new_template("Hello", virtual_path: nil)
     render
     assert_equal "Hello", @template.source
   end
@@ -99,7 +101,7 @@ class TestERBTemplate < ActiveSupport::TestCase
   def test_locals
     @template = new_template("<%= my_local %>")
     @template.locals = [:my_local]
-    assert_equal "I am a local", render(:my_local => "I am a local")
+    assert_equal "I am a local", render(my_local: "I am a local")
   end
 
   def test_restores_buffer
@@ -116,23 +118,23 @@ class TestERBTemplate < ActiveSupport::TestCase
   end
 
   def test_refresh_with_templates
-    @template = new_template("Hello", :virtual_path => "test/foo/bar")
+    @template = new_template("Hello", virtual_path: "test/foo/bar")
     @template.locals = [:key]
-    assert_called_with(@context.lookup_context, :find_template,["bar", %w(test/foo), false, [:key]], returns: "template") do
+    assert_called_with(@context.lookup_context, :find_template, ["bar", %w(test/foo), false, [:key]], returns: "template") do
       assert_equal "template", @template.refresh(@context)
     end
   end
 
   def test_refresh_with_partials
-    @template = new_template("Hello", :virtual_path => "test/_foo")
+    @template = new_template("Hello", virtual_path: "test/_foo")
     @template.locals = [:key]
-    assert_called_with(@context.lookup_context, :find_template,[ "foo", %w(test), true, [:key]], returns: "partial") do
+    assert_called_with(@context.lookup_context, :find_template, ["foo", %w(test), true, [:key]], returns: "partial") do
       assert_equal "partial", @template.refresh(@context)
     end
   end
 
   def test_refresh_raises_an_error_without_virtual_path
-    @template = new_template("Hello", :virtual_path => nil)
+    @template = new_template("Hello", virtual_path: nil)
     assert_raise RuntimeError do
       @template.refresh(@context)
     end
@@ -171,14 +173,14 @@ class TestERBTemplate < ActiveSupport::TestCase
   # inside Rails.
   def test_lying_with_magic_comment
     assert_raises(ActionView::Template::Error) do
-      @template = new_template("# encoding: UTF-8\nhello \xFCmlat", :virtual_path => nil)
+      @template = new_template("# encoding: UTF-8\nhello \xFCmlat", virtual_path: nil)
       render
     end
   end
 
   def test_encoding_can_be_specified_with_magic_comment_in_erb
     with_external_encoding Encoding::UTF_8 do
-      @template = new_template("<%# encoding: ISO-8859-1 %>hello \xFCmlat", :virtual_path => nil)
+      @template = new_template("<%# encoding: ISO-8859-1 %>hello \xFCmlat", virtual_path: nil)
       assert_equal Encoding::UTF_8, render.encoding
       assert_equal "hello \u{fc}mlat", render
     end
@@ -186,10 +188,12 @@ class TestERBTemplate < ActiveSupport::TestCase
 
   def test_error_when_template_isnt_valid_utf8
     e = assert_raises ActionView::Template::Error do
-      @template = new_template("hello \xFCmlat", :virtual_path => nil)
+      @template = new_template("hello \xFCmlat", virtual_path: nil)
       render
     end
-    assert_match(/\xFC/, e.message)
+    # Hack: We write the regexp this way because the parser of RuboCop
+    # errs with /\xFC/.
+    assert_match(Regexp.new("\xFC"), e.message)
   end
 
   def with_external_encoding(encoding)
diff --git a/actionview/test/template/test_case_test.rb b/actionview/test/template/test_case_test.rb
index d69d5819b6..05e5f21ce4 100644
--- a/actionview/test/template/test_case_test.rb
+++ b/actionview/test/template/test_case_test.rb
@@ -1,20 +1,21 @@
-require 'abstract_unit'
-require 'rails/engine'
+# frozen_string_literal: true
 
-module ActionView
+require "abstract_unit"
+require "rails/engine"
 
+module ActionView
   module ATestHelper
   end
 
   module AnotherTestHelper
     def from_another_helper
-      'Howdy!'
+      "Howdy!"
     end
   end
 
   module ASharedTestHelper
     def from_shared_helper
-      'Holla!'
+      "Holla!"
     end
   end
 
@@ -26,8 +27,8 @@ module ActionView
       def self.included(test_case)
         test_case.class_eval do
           test "helpers defined on ActionView::TestCase are available" do
-            assert test_case.ancestors.include?(ASharedTestHelper)
-            assert_equal 'Holla!', from_shared_helper
+            assert_includes test_case.ancestors, ASharedTestHelper
+            assert_equal "Holla!", from_shared_helper
           end
         end
       end
@@ -51,22 +52,22 @@ module ActionView
     end
 
     test "retrieve non existing config values" do
-      assert_equal nil, ActionView::Base.new.config.something_odd
+      assert_nil ActionView::Base.new.config.something_odd
     end
 
     test "works without testing a helper module" do
-      assert_equal 'Eloy', render('developers/developer', :developer => DeveloperStruct.new('Eloy'))
+      assert_equal "Eloy", render("developers/developer", developer: DeveloperStruct.new("Eloy"))
     end
 
     test "can render a layout with block" do
       assert_equal "Before (ChrisCruft)\n!\nAfter",
-                    render(:layout => "test/layout_for_partial", :locals => {:name => "ChrisCruft"}) {"!"}
+                    render(layout: "test/layout_for_partial", locals: { name: "ChrisCruft" }) { "!" }
     end
 
     helper AnotherTestHelper
     test "additional helper classes can be specified as in a controller" do
-      assert test_case.ancestors.include?(AnotherTestHelper)
-      assert_equal 'Howdy!', from_another_helper
+      assert_includes test_case.ancestors, AnotherTestHelper
+      assert_equal "Howdy!", from_another_helper
     end
 
     test "determine_default_helper_class returns nil if the test name constant resolves to a class" do
@@ -86,7 +87,7 @@ module ActionView
     end
 
     test "uses controller lookup context" do
-      assert_equal self.lookup_context, @controller.lookup_context
+      assert_equal lookup_context, @controller.lookup_context
     end
   end
 
@@ -97,44 +98,44 @@ module ActionView
     tests ATestHelper
     test "tests the specified helper module" do
       assert_equal ATestHelper, test_case.helper_class
-      assert test_case.ancestors.include?(ATestHelper)
+      assert_includes test_case.ancestors, ATestHelper
     end
 
     helper AnotherTestHelper
     test "additional helper classes can be specified as in a controller" do
-      assert test_case.ancestors.include?(AnotherTestHelper)
-      assert_equal 'Howdy!', from_another_helper
+      assert_includes test_case.ancestors, AnotherTestHelper
+      assert_equal "Howdy!", from_another_helper
 
       test_case.helper_class.module_eval do
         def render_from_helper
           from_another_helper
         end
       end
-      assert_equal 'Howdy!', render(:partial => 'test/from_helper')
+      assert_equal "Howdy!", render(partial: "test/from_helper")
     end
   end
 
   class HelperInclusionTest < ActionView::TestCase
     module RenderHelper
       def render_from_helper
-        render :partial => 'customer', :collection => @customers
+        render partial: "customer", collection: @customers
       end
     end
 
     helper RenderHelper
 
     test "helper class that is being tested is always included in view instance" do
-      @controller.controller_path = 'test'
+      @controller.controller_path = "test"
 
-      @customers = [DeveloperStruct.new('Eloy'), DeveloperStruct.new('Manfred')]
-      assert_match(/Hello: EloyHello: Manfred/, render(:partial => 'test/from_helper'))
+      @customers = [DeveloperStruct.new("Eloy"), DeveloperStruct.new("Manfred")]
+      assert_match(/Hello: EloyHello: Manfred/, render(partial: "test/from_helper"))
     end
   end
 
   class ControllerHelperMethod < ActionView::TestCase
     module SomeHelper
       def some_method
-        render :partial => 'test/from_helper'
+        render partial: "test/from_helper"
       end
     end
 
@@ -148,21 +149,21 @@ module ActionView
       EOF
       @controller.class.helper_method :render_from_helper
 
-      assert_equal 'controller_helper_method', some_method
+      assert_equal "controller_helper_method", some_method
     end
   end
 
   class ViewAssignsTest < ActionView::TestCase
     test "view_assigns returns a Hash of user defined ivars" do
-      @a = 'b'
-      @c = 'd'
-      assert_equal({:a => 'b', :c => 'd'}, view_assigns)
+      @a = "b"
+      @c = "d"
+      assert_equal({ a: "b", c: "d" }, view_assigns)
     end
 
     test "view_assigns excludes internal ivars" do
       INTERNAL_IVARS.each do |ivar|
         assert defined?(ivar), "expected #{ivar} to be defined"
-        assert !view_assigns.keys.include?(ivar.to_s.tr('@', '').to_sym), "expected #{ivar} to be excluded from view_assigns"
+        assert_not_includes view_assigns.keys, ivar.to_s.tr("@", "").to_sym, "expected #{ivar} to be excluded from view_assigns"
       end
     end
   end
@@ -174,10 +175,10 @@ module ActionView
       end
     end)
     test "is able to make methods available to the view" do
-      assert_equal 'Word!', render(:partial => 'test/from_helper')
+      assert_equal "Word!", render(partial: "test/from_helper")
     end
 
-    def from_test_case; 'Word!'; end
+    def from_test_case; "Word!"; end
     helper_method :from_test_case
   end
 
@@ -193,7 +194,6 @@ module ActionView
     test "protect_from_forgery? in any helpers returns false" do
       assert !view.help_me
     end
-
   end
 
   class ATestHelperTest < ActionView::TestCase
@@ -202,30 +202,30 @@ module ActionView
 
     test "inflects the name of the helper module to test from the test case class" do
       assert_equal ATestHelper, test_case.helper_class
-      assert test_case.ancestors.include?(ATestHelper)
+      assert_includes test_case.ancestors, ATestHelper
     end
 
     test "a configured test controller is available" do
       assert_kind_of ActionController::Base, controller
-      assert_equal '', controller.controller_path
+      assert_equal "", controller.controller_path
     end
 
     test "no additional helpers should shared across test cases" do
-      assert !test_case.ancestors.include?(AnotherTestHelper)
+      assert_not_includes test_case.ancestors, AnotherTestHelper
       assert_raise(NoMethodError) { send :from_another_helper }
     end
 
     test "is able to use routes" do
-      controller.request.assign_parameters(@routes, 'foo', 'index', {}, '/foo', [])
-      assert_equal '/foo', url_for
-      assert_equal '/bar', url_for(:controller => 'bar')
+      controller.request.assign_parameters(@routes, "foo", "index", {}, "/foo", [])
+      assert_equal "/foo", url_for
+      assert_equal "/bar", url_for(controller: "bar")
     end
 
     test "is able to use named routes" do
       with_routing do |set|
         set.draw { resources :contents }
-        assert_equal 'http://test.host/contents/new', new_content_url
-        assert_equal 'http://test.host/contents/1',   content_url(:id => 1)
+        assert_equal "http://test.host/contents/new", new_content_url
+        assert_equal "http://test.host/contents/1",   content_url(id: 1)
       end
     end
 
@@ -236,7 +236,7 @@ module ActionView
             @routes ||= ActionDispatch::Routing::RouteSet.new
           end
 
-          routes.draw { get "bar", :to => lambda {} }
+          routes.draw { get "bar", to: lambda {} }
 
           def self.call(*)
           end
@@ -244,7 +244,7 @@ module ActionView
 
         set.draw { mount app => "/foo", :as => "foo_app" }
 
-        assert_equal '/foo/bar', foo_app.bar_path
+        assert_equal "/foo/bar", foo_app.bar_path
       end
     end
 
@@ -257,21 +257,21 @@ module ActionView
           end
         end
 
-        assert_equal 'http://test.host/contents/new', render(:partial => 'test/from_helper')
+        assert_equal "http://test.host/contents/new", render(partial: "test/from_helper")
       end
     end
 
     test "is able to render partials with local variables" do
-      assert_equal 'Eloy', render('developers/developer', :developer => DeveloperStruct.new('Eloy'))
-      assert_equal 'Eloy', render(:partial => 'developers/developer',
-                                  :locals => { :developer => DeveloperStruct.new('Eloy') })
+      assert_equal "Eloy", render("developers/developer", developer: DeveloperStruct.new("Eloy"))
+      assert_equal "Eloy", render(partial: "developers/developer",
+                                  locals: { developer: DeveloperStruct.new("Eloy") })
     end
 
     test "is able to render partials from templates and also use instance variables" do
       @controller.controller_path = "test"
 
-      @customers = [DeveloperStruct.new('Eloy'), DeveloperStruct.new('Manfred')]
-      assert_match(/Hello: EloyHello: Manfred/, render(:file => 'test/list'))
+      @customers = [DeveloperStruct.new("Eloy"), DeveloperStruct.new("Manfred")]
+      assert_match(/Hello: EloyHello: Manfred/, render(file: "test/list"))
     end
 
     test "is able to render partials from templates and also use instance variables after view has been referenced" do
@@ -279,37 +279,44 @@ module ActionView
 
       view
 
-      @customers = [DeveloperStruct.new('Eloy'), DeveloperStruct.new('Manfred')]
-      assert_match(/Hello: EloyHello: Manfred/, render(:file => 'test/list'))
+      @customers = [DeveloperStruct.new("Eloy"), DeveloperStruct.new("Manfred")]
+      assert_match(/Hello: EloyHello: Manfred/, render(file: "test/list"))
     end
 
+    test "is able to use helpers that depend on the view flow" do
+      assert_not content_for?(:foo)
+
+      content_for :foo, "bar"
+      assert content_for?(:foo)
+      assert_equal "bar", content_for(:foo)
+    end
   end
 
   class AssertionsTest < ActionView::TestCase
     def render_from_helper
-      form_tag('/foo') do
-        safe_concat render(:text => '<ul><li>foo</li></ul>')
+      form_tag("/foo") do
+        safe_concat render(plain: "<ul><li>foo</li></ul>")
       end
     end
     helper_method :render_from_helper
 
     test "uses the output_buffer for assert_select" do
-      render(:partial => 'test/from_helper')
+      render(partial: "test/from_helper")
 
-      assert_select 'form' do
-        assert_select 'li', :text => 'foo'
+      assert_select "form" do
+        assert_select "li", text: "foo"
       end
     end
 
     test "do not memoize the document_root_element in view tests" do
-      concat form_tag('/foo')
+      concat form_tag("/foo")
 
-      assert_select 'form'
+      assert_select "form"
 
-      concat content_tag(:b, 'Strong', class: 'foo')
+      concat content_tag(:b, "Strong", class: "foo")
 
-      assert_select 'form'
-      assert_select 'b.foo'
+      assert_select "form"
+      assert_select "b.foo"
     end
   end
 
diff --git a/actionview/test/template/test_test.rb b/actionview/test/template/test_test.rb
index e1ff639979..78ba536dfc 100644
--- a/actionview/test/template/test_test.rb
+++ b/actionview/test/template/test_test.rb
@@ -1,4 +1,6 @@
-require 'abstract_unit'
+# frozen_string_literal: true
+
+require "abstract_unit"
 
 module PeopleHelper
   def title(text)
@@ -41,7 +43,7 @@ class PeopleHelperTest < ActionView::TestCase
         extend ActiveModel::Naming
         def to_model; self; end
         def persisted?; true; end
-        def self.name; 'Minitest::Mock'; end
+        def self.name; "Minitest::Mock"; end
       }.new "David"
 
       the_model = nil
@@ -60,7 +62,7 @@ class PeopleHelperTest < ActionView::TestCase
     def with_test_route_set
       with_routing do |set|
         set.draw do
-          get 'people', :to => 'people#index', :as => :people
+          get "people", to: "people#index", as: :people
         end
         yield
       end
@@ -84,7 +86,7 @@ class CrazySymbolHelperTest < ActionView::TestCase
 end
 
 class CrazyStringHelperTest < ActionView::TestCase
-  tests 'people'
+  tests "people"
 
   def test_set_helper_class_using_string
     assert_equal PeopleHelper, self.class.helper_class
diff --git a/actionview/test/template/testing/fixture_resolver_test.rb b/actionview/test/template/testing/fixture_resolver_test.rb
index d6cfa997cd..9954e3500d 100644
--- a/actionview/test/template/testing/fixture_resolver_test.rb
+++ b/actionview/test/template/testing/fixture_resolver_test.rb
@@ -1,15 +1,17 @@
-require 'abstract_unit'
+# frozen_string_literal: true
+
+require "abstract_unit"
 
 class FixtureResolverTest < ActiveSupport::TestCase
   def test_should_return_empty_list_for_unknown_path
     resolver = ActionView::FixtureResolver.new()
-    templates = resolver.find_all("path", "arbitrary", false, {:locale => [], :formats => [:html], :variants => [], :handlers => []})
+    templates = resolver.find_all("path", "arbitrary", false, locale: [], formats: [:html], variants: [], handlers: [])
     assert_equal [], templates, "expected an empty list of templates"
   end
 
   def test_should_return_template_for_declared_path
     resolver = ActionView::FixtureResolver.new("arbitrary/path.erb" => "this text")
-    templates = resolver.find_all("path", "arbitrary", false, {:locale => [], :formats => [:html], :variants => [], :handlers => [:erb]})
+    templates = resolver.find_all("path", "arbitrary", false, locale: [], formats: [:html], variants: [], handlers: [:erb])
     assert_equal 1, templates.size, "expected one template"
     assert_equal "this text",      templates.first.source
     assert_equal "arbitrary/path", templates.first.virtual_path
diff --git a/actionview/test/template/testing/null_resolver_test.rb b/actionview/test/template/testing/null_resolver_test.rb
index 55ec36e753..53364c1d90 100644
--- a/actionview/test/template/testing/null_resolver_test.rb
+++ b/actionview/test/template/testing/null_resolver_test.rb
@@ -1,9 +1,11 @@
-require 'abstract_unit'
+# frozen_string_literal: true
+
+require "abstract_unit"
 
 class NullResolverTest < ActiveSupport::TestCase
   def test_should_return_template_for_any_path
     resolver = ActionView::NullResolver.new()
-    templates = resolver.find_all("path.erb", "arbitrary", false, {:locale => [], :formats => [:html], :handlers => []})
+    templates = resolver.find_all("path.erb", "arbitrary", false, locale: [], formats: [:html], handlers: [])
     assert_equal 1, templates.size, "expected one template"
     assert_equal "Template generated by Null Resolver", templates.first.source
     assert_equal "arbitrary/path.erb", templates.first.virtual_path.to_s
diff --git a/actionview/test/template/text_helper_test.rb b/actionview/test/template/text_helper_test.rb
index 03c7597505..f247de066f 100644
--- a/actionview/test/template/text_helper_test.rb
+++ b/actionview/test/template/text_helper_test.rb
@@ -1,4 +1,6 @@
-require 'abstract_unit'
+# frozen_string_literal: true
+
+require "abstract_unit"
 
 class TextHelperTest < ActionView::TestCase
   tests ActionView::Helpers::TextHelper
@@ -11,9 +13,9 @@ class TextHelperTest < ActionView::TestCase
   end
 
   def test_concat
-    self.output_buffer = 'foo'
-    assert_equal 'foobar', concat('bar')
-    assert_equal 'foobar', output_buffer
+    self.output_buffer = "foo".dup
+    assert_equal "foobar", concat("bar")
+    assert_equal "foobar", output_buffer
   end
 
   def test_simple_format_should_be_html_safe
@@ -38,8 +40,8 @@ class TextHelperTest < ActionView::TestCase
     text = "A\r\n  \nB\n\n\r\n\t\nC\nD".freeze
     assert_equal "<p>A\n<br />  \n<br />B</p>\n\n<p>\t\n<br />C\n<br />D</p>", simple_format(text)
 
-    assert_equal %q(<p class="test">This is a classy test</p>), simple_format("This is a classy test", :class => 'test')
-    assert_equal %Q(<p class="test">para 1</p>\n\n<p class="test">para 2</p>), simple_format("para 1\n\npara 2", :class => 'test')
+    assert_equal '<p class="test">This is a classy test</p>', simple_format("This is a classy test", class: "test")
+    assert_equal %Q(<p class="test">para 1</p>\n\n<p class="test">para 2</p>), simple_format("para 1\n\npara 2", class: "test")
   end
 
   def test_simple_format_should_sanitize_input_when_sanitize_option_is_not_false
@@ -47,20 +49,20 @@ class TextHelperTest < ActionView::TestCase
   end
 
   def test_simple_format_should_sanitize_input_when_sanitize_option_is_true
-    assert_equal '<p><b> test with unsafe string </b>code!</p>',
-      simple_format('<b> test with unsafe string </b><script>code!</script>', {}, sanitize: true)
+    assert_equal "<p><b> test with unsafe string </b>code!</p>",
+      simple_format("<b> test with unsafe string </b><script>code!</script>", {}, { sanitize: true })
   end
 
   def test_simple_format_should_not_sanitize_input_when_sanitize_option_is_false
-    assert_equal "<p><b> test with unsafe string </b><script>code!</script></p>", simple_format("<b> test with unsafe string </b><script>code!</script>", {}, :sanitize => false)
+    assert_equal "<p><b> test with unsafe string </b><script>code!</script></p>", simple_format("<b> test with unsafe string </b><script>code!</script>", {}, { sanitize: false })
   end
 
   def test_simple_format_with_custom_wrapper
-    assert_equal "<div></div>", simple_format(nil, {}, :wrapper_tag => "div")
+    assert_equal "<div></div>", simple_format(nil, {}, { wrapper_tag: "div" })
   end
 
   def test_simple_format_with_custom_wrapper_and_multi_line_breaks
-    assert_equal "<div>We want to put a wrapper...</div>\n\n<div>...right there.</div>", simple_format("We want to put a wrapper...\n\n...right there.", {}, :wrapper_tag => "div")
+    assert_equal "<div>We want to put a wrapper...</div>\n\n<div>...right there.</div>", simple_format("We want to put a wrapper...\n\n...right there.", {}, { wrapper_tag: "div" })
   end
 
   def test_simple_format_should_not_change_the_text_passed
@@ -71,22 +73,22 @@ class TextHelperTest < ActionView::TestCase
   end
 
   def test_simple_format_does_not_modify_the_html_options_hash
-    options = { :class => "foobar"}
+    options = { class: "foobar" }
     passed_options = options.dup
     simple_format("some text", passed_options)
     assert_equal options, passed_options
   end
 
   def test_simple_format_does_not_modify_the_options_hash
-    options = { :wrapper_tag => :div, :sanitize => false }
+    options = { wrapper_tag: :div, sanitize: false }
     passed_options = options.dup
     simple_format("some text", {}, passed_options)
     assert_equal options, passed_options
   end
 
   def test_truncate
-    assert_equal "Hello World!", truncate("Hello World!", :length => 12)
-    assert_equal "Hello Wor...", truncate("Hello World!!", :length => 12)
+    assert_equal "Hello World!", truncate("Hello World!", length: 12)
+    assert_equal "Hello Wor...", truncate("Hello World!!", length: 12)
   end
 
   def test_truncate_should_use_default_length_of_30
@@ -95,21 +97,21 @@ class TextHelperTest < ActionView::TestCase
   end
 
   def test_truncate_with_options_hash
-    assert_equal "This is a string that wil[...]", truncate("This is a string that will go longer then the default truncate length of 30", :omission => "[...]")
-    assert_equal "Hello W...", truncate("Hello World!", :length => 10)
-    assert_equal "Hello[...]", truncate("Hello World!", :omission => "[...]", :length => 10)
-    assert_equal "Hello[...]", truncate("Hello Big World!", :omission => "[...]", :length => 13, :separator => ' ')
-    assert_equal "Hello Big[...]", truncate("Hello Big World!", :omission => "[...]", :length => 14, :separator => ' ')
-    assert_equal "Hello Big[...]", truncate("Hello Big World!", :omission => "[...]", :length => 15, :separator => ' ')
+    assert_equal "This is a string that wil[...]", truncate("This is a string that will go longer then the default truncate length of 30", omission: "[...]")
+    assert_equal "Hello W...", truncate("Hello World!", length: 10)
+    assert_equal "Hello[...]", truncate("Hello World!", omission: "[...]", length: 10)
+    assert_equal "Hello[...]", truncate("Hello Big World!", omission: "[...]", length: 13, separator: " ")
+    assert_equal "Hello Big[...]", truncate("Hello Big World!", omission: "[...]", length: 14, separator: " ")
+    assert_equal "Hello Big[...]", truncate("Hello Big World!", omission: "[...]", length: 15, separator: " ")
   end
 
   def test_truncate_multibyte
-    assert_equal "\354\225\204\353\246\254\353\236\221 \354\225\204\353\246\254 ...".force_encoding(Encoding::UTF_8),
-      truncate("\354\225\204\353\246\254\353\236\221 \354\225\204\353\246\254 \354\225\204\353\235\274\353\246\254\354\230\244".force_encoding(Encoding::UTF_8), :length => 10)
+    assert_equal "\354\225\204\353\246\254\353\236\221 \354\225\204\353\246\254 ...".dup.force_encoding(Encoding::UTF_8),
+      truncate("\354\225\204\353\246\254\353\236\221 \354\225\204\353\246\254 \354\225\204\353\235\274\353\246\254\354\230\244".dup.force_encoding(Encoding::UTF_8), length: 10)
   end
 
   def test_truncate_does_not_modify_the_options_hash
-    options = { :length => 10 }
+    options = { length: 10 }
     passed_options = options.dup
     truncate("some text", passed_options)
     assert_equal options, passed_options
@@ -117,49 +119,49 @@ class TextHelperTest < ActionView::TestCase
 
   def test_truncate_with_link_options
     assert_equal "Here is a long test and ...<a href=\"#\">Continue</a>",
-    truncate("Here is a long test and I need a continue to read link", :length => 27) { link_to 'Continue', '#' }
+    truncate("Here is a long test and I need a continue to read link", length: 27) { link_to "Continue", "#" }
   end
 
   def test_truncate_should_be_html_safe
-    assert truncate("Hello World!", :length => 12).html_safe?
+    assert truncate("Hello World!", length: 12).html_safe?
   end
 
   def test_truncate_should_escape_the_input
-    assert_equal "Hello &lt;sc...", truncate("Hello <script>code!</script>World!!", :length => 12)
+    assert_equal "Hello &lt;sc...", truncate("Hello <script>code!</script>World!!", length: 12)
   end
 
   def test_truncate_should_not_escape_the_input_with_escape_false
-    assert_equal "Hello <sc...", truncate("Hello <script>code!</script>World!!", :length => 12, :escape => false)
+    assert_equal "Hello <sc...", truncate("Hello <script>code!</script>World!!", length: 12, escape: false)
   end
 
   def test_truncate_with_escape_false_should_be_html_safe
-    truncated = truncate("Hello <script>code!</script>World!!", :length => 12, :escape => false)
+    truncated = truncate("Hello <script>code!</script>World!!", length: 12, escape: false)
     assert truncated.html_safe?
   end
 
   def test_truncate_with_block_should_be_html_safe
-    truncated = truncate("Here's a long test and I need a continue to read link", :length => 27) { link_to 'Continue', '#' }
+    truncated = truncate("Here's a long test and I need a continue to read link", length: 27) { link_to "Continue", "#" }
     assert truncated.html_safe?
   end
 
   def test_truncate_with_block_should_escape_the_input
     assert_equal "&lt;script&gt;code!&lt;/script&gt;He...<a href=\"#\">Continue</a>",
-      truncate("<script>code!</script>Here's a long test and I need a continue to read link", :length => 27) { link_to 'Continue', '#' }
+      truncate("<script>code!</script>Here's a long test and I need a continue to read link", length: 27) { link_to "Continue", "#" }
   end
 
   def test_truncate_with_block_should_not_escape_the_input_with_escape_false
     assert_equal "<script>code!</script>He...<a href=\"#\">Continue</a>",
-      truncate("<script>code!</script>Here's a long test and I need a continue to read link", :length => 27, :escape => false) { link_to 'Continue', '#' }
+      truncate("<script>code!</script>Here's a long test and I need a continue to read link", length: 27, escape: false) { link_to "Continue", "#" }
   end
 
   def test_truncate_with_block_with_escape_false_should_be_html_safe
-    truncated = truncate("<script>code!</script>Here's a long test and I need a continue to read link", :length => 27, :escape => false) { link_to 'Continue', '#' }
+    truncated = truncate("<script>code!</script>Here's a long test and I need a continue to read link", length: 27, escape: false) { link_to "Continue", "#" }
     assert truncated.html_safe?
   end
 
   def test_truncate_with_block_should_escape_the_block
     assert_equal "Here is a long test and ...&lt;script&gt;alert(&#39;foo&#39;);&lt;/script&gt;",
-      truncate("Here is a long test and I need a continue to read link", :length => 27) { "<script>alert('foo');</script>" }
+      truncate("Here is a long test and I need a continue to read link", length: 27) { "<script>alert('foo');</script>" }
   end
 
   def test_highlight_should_be_html_safe
@@ -179,7 +181,7 @@ class TextHelperTest < ActionView::TestCase
 
     assert_equal(
       "This is a <b>beautiful</b> morning, but also a <b>beautiful</b> day",
-      highlight("This is a beautiful morning, but also a beautiful day", "beautiful", :highlighter => '<b>\1</b>')
+      highlight("This is a beautiful morning, but also a beautiful day", "beautiful", highlighter: '<b>\1</b>')
     )
 
     assert_equal(
@@ -189,11 +191,11 @@ class TextHelperTest < ActionView::TestCase
   end
 
   def test_highlight_pending
-    assert_equal '   ', highlight('   ', 'blank text is returned verbatim')
+    assert_equal "   ", highlight("   ", "blank text is returned verbatim")
   end
 
   def test_highlight_should_return_blank_string_for_nil
-    assert_equal '', highlight(nil, 'blank string is returned for nil')
+    assert_equal "", highlight(nil, "blank string is returned for nil")
   end
 
   def test_highlight_should_sanitize_input
@@ -206,7 +208,7 @@ class TextHelperTest < ActionView::TestCase
   def test_highlight_should_not_sanitize_if_sanitize_option_if_false
     assert_equal(
       "This is a <mark>beautiful</mark> morning<script>code!</script>",
-      highlight("This is a beautiful morning<script>code!</script>", "beautiful", :sanitize => false)
+      highlight("This is a beautiful morning<script>code!</script>", "beautiful", sanitize: false)
     )
   end
 
@@ -233,7 +235,7 @@ class TextHelperTest < ActionView::TestCase
   end
 
   def test_highlight_with_multiple_phrases_in_one_pass
-    assert_equal %(<em>wow</em> <em>em</em>), highlight('wow em', %w(wow em), :highlighter => '<em>\1</em>')
+    assert_equal %(<em>wow</em> <em>em</em>), highlight("wow em", %w(wow em), highlighter: '<em>\1</em>')
   end
 
   def test_highlight_with_html
@@ -259,12 +261,12 @@ class TextHelperTest < ActionView::TestCase
     )
     assert_equal(
       "<div>abc <b>div</b></div>",
-      highlight("<div>abc div</div>", "div", :highlighter => '<b>\1</b>')
+      highlight("<div>abc div</div>", "div", highlighter: '<b>\1</b>')
     )
   end
 
   def test_highlight_does_not_modify_the_options_hash
-    options = { :highlighter => '<b>\1</b>', :sanitize => false }
+    options = { highlighter: '<b>\1</b>', sanitize: false }
     passed_options = options.dup
     highlight("<div>abc div</div>", "div", passed_options)
     assert_equal options, passed_options
@@ -278,89 +280,89 @@ class TextHelperTest < ActionView::TestCase
   end
 
   def test_excerpt
-    assert_equal("...is a beautiful morn...", excerpt("This is a beautiful morning", "beautiful", :radius => 5))
-    assert_equal("This is a...", excerpt("This is a beautiful morning", "this", :radius => 5))
-    assert_equal("...iful morning", excerpt("This is a beautiful morning", "morning", :radius => 5))
+    assert_equal("...is a beautiful morn...", excerpt("This is a beautiful morning", "beautiful", radius: 5))
+    assert_equal("This is a...", excerpt("This is a beautiful morning", "this", radius: 5))
+    assert_equal("...iful morning", excerpt("This is a beautiful morning", "morning", radius: 5))
     assert_nil excerpt("This is a beautiful morning", "day")
   end
 
   def test_excerpt_with_regex
-    assert_equal('...is a beautiful! mor...', excerpt('This is a beautiful! morning', 'beautiful', :radius => 5))
-    assert_equal('...is a beautiful? mor...', excerpt('This is a beautiful? morning', 'beautiful', :radius => 5))
-    assert_equal('...is a beautiful? mor...', excerpt('This is a beautiful? morning', /\bbeau\w*\b/i, :radius => 5))
-    assert_equal('...is a beautiful? mor...', excerpt('This is a beautiful? morning', /\b(beau\w*)\b/i, :radius => 5))
-    assert_equal("...udge Allen and...", excerpt("This day was challenging for judge Allen and his colleagues.", /\ballen\b/i, :radius => 5))
-    assert_equal("...judge Allen and...", excerpt("This day was challenging for judge Allen and his colleagues.", /\ballen\b/i, :radius => 1, :separator => ' '))
-    assert_equal("...was challenging for...", excerpt("This day was challenging for judge Allen and his colleagues.", /\b(\w*allen\w*)\b/i, :radius => 5))
+    assert_equal("...is a beautiful! mor...", excerpt("This is a beautiful! morning", "beautiful", radius: 5))
+    assert_equal("...is a beautiful? mor...", excerpt("This is a beautiful? morning", "beautiful", radius: 5))
+    assert_equal("...is a beautiful? mor...", excerpt("This is a beautiful? morning", /\bbeau\w*\b/i, radius: 5))
+    assert_equal("...is a beautiful? mor...", excerpt("This is a beautiful? morning", /\b(beau\w*)\b/i, radius: 5))
+    assert_equal("...udge Allen and...", excerpt("This day was challenging for judge Allen and his colleagues.", /\ballen\b/i, radius: 5))
+    assert_equal("...judge Allen and...", excerpt("This day was challenging for judge Allen and his colleagues.", /\ballen\b/i, radius: 1, separator: " "))
+    assert_equal("...was challenging for...", excerpt("This day was challenging for judge Allen and his colleagues.", /\b(\w*allen\w*)\b/i, radius: 5))
   end
 
   def test_excerpt_should_not_be_html_safe
-    assert !excerpt('This is a beautiful! morning', 'beautiful', :radius => 5).html_safe?
+    assert !excerpt("This is a beautiful! morning", "beautiful", radius: 5).html_safe?
   end
 
   def test_excerpt_in_borderline_cases
-    assert_equal("", excerpt("", "", :radius => 0))
-    assert_equal("a", excerpt("a", "a", :radius => 0))
-    assert_equal("...b...", excerpt("abc", "b", :radius => 0))
-    assert_equal("abc", excerpt("abc", "b", :radius => 1))
-    assert_equal("abc...", excerpt("abcd", "b", :radius => 1))
-    assert_equal("...abc", excerpt("zabc", "b", :radius => 1))
-    assert_equal("...abc...", excerpt("zabcd", "b", :radius => 1))
-    assert_equal("zabcd", excerpt("zabcd", "b", :radius => 2))
+    assert_equal("", excerpt("", "", radius: 0))
+    assert_equal("a", excerpt("a", "a", radius: 0))
+    assert_equal("...b...", excerpt("abc", "b", radius: 0))
+    assert_equal("abc", excerpt("abc", "b", radius: 1))
+    assert_equal("abc...", excerpt("abcd", "b", radius: 1))
+    assert_equal("...abc", excerpt("zabc", "b", radius: 1))
+    assert_equal("...abc...", excerpt("zabcd", "b", radius: 1))
+    assert_equal("zabcd", excerpt("zabcd", "b", radius: 2))
 
     # excerpt strips the resulting string before ap-/prepending excerpt_string.
     # whether this behavior is meaningful when excerpt_string is not to be
     # appended is questionable.
-    assert_equal("zabcd", excerpt("  zabcd  ", "b", :radius => 4))
-    assert_equal("...abc...", excerpt("z  abc  d", "b", :radius => 1))
+    assert_equal("zabcd", excerpt("  zabcd  ", "b", radius: 4))
+    assert_equal("...abc...", excerpt("z  abc  d", "b", radius: 1))
   end
 
   def test_excerpt_with_omission
-    assert_equal("[...]is a beautiful morn[...]", excerpt("This is a beautiful morning", "beautiful", :omission => "[...]",:radius => 5))
+    assert_equal("[...]is a beautiful morn[...]", excerpt("This is a beautiful morning", "beautiful", omission: "[...]", radius: 5))
     assert_equal(
       "This is the ultimate supercalifragilisticexpialidoceous very looooooooooooooooooong looooooooooooong beautiful morning with amazing sunshine and awesome tempera[...]",
       excerpt("This is the ultimate supercalifragilisticexpialidoceous very looooooooooooooooooong looooooooooooong beautiful morning with amazing sunshine and awesome temperatures. So what are you gonna do about it?", "very",
-      :omission => "[...]")
+      omission: "[...]")
     )
   end
 
   def test_excerpt_with_utf8
-    assert_equal("...\357\254\203ciency could not be...".force_encoding(Encoding::UTF_8), excerpt("That's why e\357\254\203ciency could not be helped".force_encoding(Encoding::UTF_8), 'could', :radius => 8))
+    assert_equal("...\357\254\203ciency could not be...".dup.force_encoding(Encoding::UTF_8), excerpt("That's why e\357\254\203ciency could not be helped".dup.force_encoding(Encoding::UTF_8), "could", radius: 8))
   end
 
   def test_excerpt_does_not_modify_the_options_hash
-    options = { :omission => "[...]",:radius => 5 }
+    options = { omission: "[...]", radius: 5 }
     passed_options = options.dup
     excerpt("This is a beautiful morning", "beautiful", passed_options)
     assert_equal options, passed_options
   end
 
   def test_excerpt_with_separator
-    options = { :separator => ' ', :radius => 1 }
-    assert_equal('...a very beautiful...', excerpt('This is a very beautiful morning', 'very', options))
-    assert_equal('This is...', excerpt('This is a very beautiful morning', 'this', options))
-    assert_equal('...beautiful morning', excerpt('This is a very beautiful morning', 'morning', options))
+    options = { separator: " ", radius: 1 }
+    assert_equal("...a very beautiful...", excerpt("This is a very beautiful morning", "very", options))
+    assert_equal("This is...", excerpt("This is a very beautiful morning", "this", options))
+    assert_equal("...beautiful morning", excerpt("This is a very beautiful morning", "morning", options))
 
-    options = { :separator => "\n", :radius => 0 }
-    assert_equal("...very long...", excerpt("my very\nvery\nvery long\nstring", 'long', options))
+    options = { separator: "\n", radius: 0 }
+    assert_equal("...very long...", excerpt("my very\nvery\nvery long\nstring", "long", options))
 
-    options = { :separator => "\n", :radius => 1 }
-    assert_equal("...very\nvery long\nstring", excerpt("my very\nvery\nvery long\nstring", 'long', options))
+    options = { separator: "\n", radius: 1 }
+    assert_equal("...very\nvery long\nstring", excerpt("my very\nvery\nvery long\nstring", "long", options))
 
-    assert_equal excerpt('This is a beautiful morning', 'a'),
-                 excerpt('This is a beautiful morning', 'a', separator: nil)
+    assert_equal excerpt("This is a beautiful morning", "a"),
+                 excerpt("This is a beautiful morning", "a", separator: nil)
   end
 
   def test_word_wrap
-    assert_equal("my very very\nvery long\nstring", word_wrap("my very very very long string", :line_width => 15))
+    assert_equal("my very very\nvery long\nstring", word_wrap("my very very very long string", line_width: 15))
   end
 
   def test_word_wrap_with_extra_newlines
-    assert_equal("my very very\nvery long\nstring\n\nwith another\nline", word_wrap("my very very very long string\n\nwith another line", :line_width => 15))
+    assert_equal("my very very\nvery long\nstring\n\nwith another\nline", word_wrap("my very very very long string\n\nwith another line", line_width: 15))
   end
 
   def test_word_wrap_does_not_modify_the_options_hash
-    options = { :line_width => 15 }
+    options = { line_width: 15 }
     passed_options = options.dup
     word_wrap("some text", passed_options)
     assert_equal options, passed_options
@@ -373,12 +375,14 @@ class TextHelperTest < ActionView::TestCase
   def test_pluralization
     assert_equal("1 count", pluralize(1, "count"))
     assert_equal("2 counts", pluralize(2, "count"))
-    assert_equal("1 count", pluralize('1', "count"))
-    assert_equal("2 counts", pluralize('2', "count"))
-    assert_equal("1,066 counts", pluralize('1,066', "count"))
-    assert_equal("1.25 counts", pluralize('1.25', "count"))
-    assert_equal("1.0 count", pluralize('1.0', "count"))
-    assert_equal("1.00 count", pluralize('1.00', "count"))
+    assert_equal("1 count", pluralize("1", "count"))
+    assert_equal("2 counts", pluralize("2", "count"))
+    assert_equal("1,066 counts", pluralize("1,066", "count"))
+    assert_equal("1.25 counts", pluralize("1.25", "count"))
+    assert_equal("1.0 count", pluralize("1.0", "count"))
+    assert_equal("1.00 count", pluralize("1.00", "count"))
+    assert_equal("2 counters", pluralize(2, "count", "counters"))
+    assert_equal("0 counters", pluralize(nil, "count", "counters"))
     assert_equal("2 counters", pluralize(2, "count", plural: "counters"))
     assert_equal("0 counters", pluralize(nil, "count", plural: "counters"))
     assert_equal("2 people", pluralize(2, "person"))
@@ -394,7 +398,7 @@ class TextHelperTest < ActionView::TestCase
       I18n.locale = :de
 
       ActiveSupport::Inflector.inflections(:de) do |inflect|
-        inflect.irregular 'region', 'regionen'
+        inflect.irregular "region", "regionen"
       end
 
       assert_equal("1 region",   pluralize(1, "region"))
@@ -405,12 +409,6 @@ class TextHelperTest < ActionView::TestCase
     end
   end
 
-  def test_deprecated_plural_as_positional_argument
-    assert_deprecated do
-      pluralize(2, 'count', 'counters')
-    end
-  end
-
   def test_cycle_class
     value = Cycle.new("one", 2, "3")
     assert_equal("one", value.to_s)
@@ -458,29 +456,29 @@ class TextHelperTest < ActionView::TestCase
   end
 
   def test_named_cycles
-    assert_equal("1", cycle(1, 2, 3, :name => "numbers"))
-    assert_equal("red", cycle("red", "blue", :name => "colors"))
-    assert_equal("2", cycle(1, 2, 3, :name => "numbers"))
-    assert_equal("blue", cycle("red", "blue", :name => "colors"))
-    assert_equal("3", cycle(1, 2, 3, :name => "numbers"))
-    assert_equal("red", cycle("red", "blue", :name => "colors"))
+    assert_equal("1", cycle(1, 2, 3, name: "numbers"))
+    assert_equal("red", cycle("red", "blue", name: "colors"))
+    assert_equal("2", cycle(1, 2, 3, name: "numbers"))
+    assert_equal("blue", cycle("red", "blue", name: "colors"))
+    assert_equal("3", cycle(1, 2, 3, name: "numbers"))
+    assert_equal("red", cycle("red", "blue", name: "colors"))
   end
 
   def test_current_cycle_with_default_name
-    cycle("even","odd")
+    cycle("even", "odd")
     assert_equal "even", current_cycle
-    cycle("even","odd")
+    cycle("even", "odd")
     assert_equal "odd", current_cycle
-    cycle("even","odd")
+    cycle("even", "odd")
     assert_equal "even", current_cycle
   end
 
   def test_current_cycle_with_named_cycles
-    cycle("red", "blue", :name => "colors")
+    cycle("red", "blue", name: "colors")
     assert_equal "red", current_cycle("colors")
-    cycle("red", "blue", :name => "colors")
+    cycle("red", "blue", name: "colors")
     assert_equal "blue", current_cycle("colors")
-    cycle("red", "blue", :name => "colors")
+    cycle("red", "blue", name: "colors")
     assert_equal "red", current_cycle("colors")
   end
 
@@ -490,19 +488,19 @@ class TextHelperTest < ActionView::TestCase
   end
 
   def test_current_cycle_with_more_than_two_names
-    cycle(1,2,3)
+    cycle(1, 2, 3)
     assert_equal "1", current_cycle
-    cycle(1,2,3)
+    cycle(1, 2, 3)
     assert_equal "2", current_cycle
-    cycle(1,2,3)
+    cycle(1, 2, 3)
     assert_equal "3", current_cycle
-    cycle(1,2,3)
+    cycle(1, 2, 3)
     assert_equal "1", current_cycle
   end
 
   def test_default_named_cycle
     assert_equal("1", cycle(1, 2, 3))
-    assert_equal("2", cycle(1, 2, 3, :name => "default"))
+    assert_equal("2", cycle(1, 2, 3, name: "default"))
     assert_equal("3", cycle(1, 2, 3))
   end
 
@@ -518,13 +516,13 @@ class TextHelperTest < ActionView::TestCase
   end
 
   def test_reset_named_cycle
-    assert_equal("1", cycle(1, 2, 3, :name => "numbers"))
-    assert_equal("red", cycle("red", "blue", :name => "colors"))
+    assert_equal("1", cycle(1, 2, 3, name: "numbers"))
+    assert_equal("red", cycle("red", "blue", name: "colors"))
     reset_cycle("numbers")
-    assert_equal("1", cycle(1, 2, 3, :name => "numbers"))
-    assert_equal("blue", cycle("red", "blue", :name => "colors"))
-    assert_equal("2", cycle(1, 2, 3, :name => "numbers"))
-    assert_equal("red", cycle("red", "blue", :name => "colors"))
+    assert_equal("1", cycle(1, 2, 3, name: "numbers"))
+    assert_equal("blue", cycle("red", "blue", name: "colors"))
+    assert_equal("2", cycle(1, 2, 3, name: "numbers"))
+    assert_equal("red", cycle("red", "blue", name: "colors"))
   end
 
   def test_cycle_no_instance_variable_clashes
diff --git a/actionview/test/template/text_test.rb b/actionview/test/template/text_test.rb
index d899d54589..0c6470df21 100644
--- a/actionview/test/template/text_test.rb
+++ b/actionview/test/template/text_test.rb
@@ -1,17 +1,25 @@
-require 'abstract_unit'
+# frozen_string_literal: true
+
+require "abstract_unit"
 
 class TextTest < ActiveSupport::TestCase
-  test 'formats returns symbol for recognized MIME type' do
-    assert_equal [:text], ActionView::Template::Text.new('', :text).formats
+  test "formats always return :text" do
+    assert_equal [:text], ActionView::Template::Text.new("").formats
+  end
+
+  test "identifier should return 'text template'" do
+    assert_equal "text template", ActionView::Template::Text.new("").identifier
+  end
+
+  test "inspect should return 'text template'" do
+    assert_equal "text template", ActionView::Template::Text.new("").inspect
   end
 
-  test 'formats returns string for recognized MIME type when MIME does not have symbol' do
-    foo = Mime::Type.lookup("foo")
-    assert_nil foo.to_sym
-    assert_equal ['foo'], ActionView::Template::Text.new('', foo).formats
+  test "to_str should return a given string" do
+    assert_equal "a cat", ActionView::Template::Text.new("a cat").to_str
   end
 
-  test 'formats returns string for unknown MIME type' do
-    assert_equal ['foo'], ActionView::Template::Text.new('', 'foo').formats
+  test "render should return a given string" do
+    assert_equal "a dog", ActionView::Template::Text.new("a dog").render
   end
 end
diff --git a/actionview/test/template/translation_helper_test.rb b/actionview/test/template/translation_helper_test.rb
index 38b9284767..8956a584ff 100644
--- a/actionview/test/template/translation_helper_test.rb
+++ b/actionview/test/template/translation_helper_test.rb
@@ -1,9 +1,11 @@
-require 'abstract_unit'
+# frozen_string_literal: true
+
+require "abstract_unit"
 
 module I18n
   class CustomExceptionHandler
     def self.call(exception, locale, key, options)
-      'from CustomExceptionHandler'
+      "from CustomExceptionHandler"
     end
   end
 end
@@ -15,22 +17,22 @@ class TranslationHelperTest < ActiveSupport::TestCase
 
   setup do
     I18n.backend.store_translations(:en,
-      :translations => {
-        :templates => {
-          :found => { :foo => 'Foo' },
-          :array => { :foo => { :bar => 'Foo Bar' } },
-          :default => { :foo => 'Foo' }
+      translations: {
+        templates: {
+          found: { foo: "Foo" },
+          array: { foo: { bar: "Foo Bar" } },
+          default: { foo: "Foo" }
         },
-        :foo => 'Foo',
-        :hello => '<a>Hello World</a>',
-        :html => '<a>Hello World</a>',
-        :hello_html => '<a>Hello World</a>',
-        :interpolated_html => '<a>Hello %{word}</a>',
-        :array_html => %w(foo bar),
-        :array => %w(foo bar),
-        :count_html => {
-          :one   => '<a>One %{count}</a>',
-          :other => '<a>Other %{count}</a>'
+        foo: "Foo",
+        hello: "<a>Hello World</a>",
+        html: "<a>Hello World</a>",
+        hello_html: "<a>Hello World</a>",
+        interpolated_html: "<a>Hello %{word}</a>",
+        array_html: %w(foo bar),
+        array: %w(foo bar),
+        count_html: {
+          one: "<a>One %{count}</a>",
+          other: "<a>Other %{count}</a>"
         }
       }
     )
@@ -42,8 +44,8 @@ class TranslationHelperTest < ActiveSupport::TestCase
   end
 
   def test_delegates_setting_to_i18n
-    assert_called_with(I18n, :translate, [:foo, :locale => 'en', :raise => true], returns: "") do
-      translate :foo, :locale => 'en'
+    assert_called_with(I18n, :translate, [:foo, locale: "en", raise: true], returns: "") do
+      translate :foo, locale: "en"
     end
   end
 
@@ -58,7 +60,7 @@ class TranslationHelperTest < ActiveSupport::TestCase
     old_value = ActionView::Base.debug_missing_translation
     ActionView::Base.debug_missing_translation = false
 
-    expected = 'translation missing: en.translations.missing'
+    expected = "translation missing: en.translations.missing"
     assert_equal expected, translate(:"translations.missing")
   ensure
     ActionView::Base.debug_missing_translation = old_value
@@ -78,10 +80,10 @@ class TranslationHelperTest < ActiveSupport::TestCase
 
   def test_returns_missing_translation_message_does_filters_out_i18n_options
     expected = '<span class="translation_missing" title="translation missing: en.translations.missing, year: 2015">Missing</span>'
-    assert_equal expected, translate(:"translations.missing", year: '2015', default: [])
+    assert_equal expected, translate(:"translations.missing", year: "2015", default: [])
 
     expected = '<span class="translation_missing" title="translation missing: en.scoped.translations.missing, year: 2015">Missing</span>'
-    assert_equal expected, translate(:"translations.missing", year: '2015', scope: %i(scoped))
+    assert_equal expected, translate(:"translations.missing", year: "2015", scope: %i(scoped))
   end
 
   def test_raises_missing_translation_message_with_raise_config_option
@@ -96,14 +98,14 @@ class TranslationHelperTest < ActiveSupport::TestCase
 
   def test_raises_missing_translation_message_with_raise_option
     assert_raise(I18n::MissingTranslationData) do
-      translate(:"translations.missing", :raise => true)
+      translate(:"translations.missing", raise: true)
     end
   end
 
   def test_uses_custom_exception_handler_when_specified
     old_exception_handler = I18n.exception_handler
     I18n.exception_handler = I18n::CustomExceptionHandler
-    assert_equal 'from CustomExceptionHandler', translate(:"translations.missing", raise: false)
+    assert_equal "from CustomExceptionHandler", translate(:"translations.missing", raise: false)
   ensure
     I18n.exception_handler = old_exception_handler
   end
@@ -111,7 +113,7 @@ class TranslationHelperTest < ActiveSupport::TestCase
   def test_uses_custom_exception_handler_when_specified_for_html
     old_exception_handler = I18n.exception_handler
     I18n.exception_handler = I18n::CustomExceptionHandler
-    assert_equal 'from CustomExceptionHandler', translate(:"translations.missing_html", raise: false)
+    assert_equal "from CustomExceptionHandler", translate(:"translations.missing_html", raise: false)
   ensure
     I18n.exception_handler = old_exception_handler
   end
@@ -122,20 +124,20 @@ class TranslationHelperTest < ActiveSupport::TestCase
   end
 
   def test_finds_translation_scoped_by_partial
-    assert_equal 'Foo', view.render(:file => 'translations/templates/found').strip
+    assert_equal "Foo", view.render(file: "translations/templates/found").strip
   end
 
   def test_finds_array_of_translations_scoped_by_partial
-    assert_equal 'Foo Bar', @view.render(:file => 'translations/templates/array').strip
+    assert_equal "Foo Bar", @view.render(file: "translations/templates/array").strip
   end
 
   def test_default_lookup_scoped_by_partial
-    assert_equal 'Foo', view.render(:file => 'translations/templates/default').strip
+    assert_equal "Foo", view.render(file: "translations/templates/default").strip
   end
 
   def test_missing_translation_scoped_by_partial
     expected = '<span class="translation_missing" title="translation missing: en.translations.templates.missing.missing">Missing</span>'
-    assert_equal expected, view.render(:file => 'translations/templates/missing').strip
+    assert_equal expected, view.render(file: "translations/templates/missing").strip
   end
 
   def test_translate_does_not_mark_plain_text_as_safe_html
@@ -152,14 +154,14 @@ class TranslationHelperTest < ActiveSupport::TestCase
 
   def test_translate_escapes_interpolations_in_translations_with_a_html_suffix
     word_struct = Struct.new(:to_s)
-    assert_equal '<a>Hello &lt;World&gt;</a>', translate(:'translations.interpolated_html', :word => '<World>')
-    assert_equal '<a>Hello &lt;World&gt;</a>', translate(:'translations.interpolated_html', :word => word_struct.new("<World>"))
+    assert_equal "<a>Hello &lt;World&gt;</a>", translate(:'translations.interpolated_html', word: "<World>")
+    assert_equal "<a>Hello &lt;World&gt;</a>", translate(:'translations.interpolated_html', word: word_struct.new("<World>"))
   end
 
   def test_translate_with_html_count
-    assert_equal '<a>One 1</a>', translate(:'translations.count_html', :count => 1)
-    assert_equal '<a>Other 2</a>', translate(:'translations.count_html', :count => 2)
-    assert_equal '<a>Other &lt;One&gt;</a>', translate(:'translations.count_html', :count => '<One>')
+    assert_equal "<a>One 1</a>", translate(:'translations.count_html', count: 1)
+    assert_equal "<a>Other 2</a>", translate(:'translations.count_html', count: 2)
+    assert_equal "<a>Other &lt;One&gt;</a>", translate(:'translations.count_html', count: "<One>")
   end
 
   def test_translation_returning_an_array_ignores_html_suffix
@@ -167,13 +169,13 @@ class TranslationHelperTest < ActiveSupport::TestCase
   end
 
   def test_translate_with_default_named_html
-    translation = translate(:'translations.missing', :default => :'translations.hello_html')
-    assert_equal '<a>Hello World</a>', translation
+    translation = translate(:'translations.missing', default: :'translations.hello_html')
+    assert_equal "<a>Hello World</a>", translation
     assert_equal true, translation.html_safe?
   end
 
   def test_translate_with_missing_default
-    translation = translate(:'translations.missing', :default => :'translations.missing_html')
+    translation = translate(:'translations.missing', default: :'translations.missing_html')
     expected = '<span class="translation_missing" title="translation missing: en.translations.missing_html">Missing Html</span>'
     assert_equal expected, translation
     assert_equal true, translation.html_safe?
@@ -181,31 +183,31 @@ class TranslationHelperTest < ActiveSupport::TestCase
 
   def test_translate_with_missing_default_and_raise_option
     assert_raise(I18n::MissingTranslationData) do
-      translate(:'translations.missing', :default => :'translations.missing_html', :raise => true)
+      translate(:'translations.missing', default: :'translations.missing_html', raise: true)
     end
   end
 
   def test_translate_with_two_defaults_named_html
-    translation = translate(:'translations.missing', :default => [:'translations.missing_html', :'translations.hello_html'])
-    assert_equal '<a>Hello World</a>', translation
+    translation = translate(:'translations.missing', default: [:'translations.missing_html', :'translations.hello_html'])
+    assert_equal "<a>Hello World</a>", translation
     assert_equal true, translation.html_safe?
   end
 
   def test_translate_with_last_default_named_html
-    translation = translate(:'translations.missing', :default => [:'translations.missing', :'translations.hello_html'])
-    assert_equal '<a>Hello World</a>', translation
+    translation = translate(:'translations.missing', default: [:'translations.missing', :'translations.hello_html'])
+    assert_equal "<a>Hello World</a>", translation
     assert_equal true, translation.html_safe?
   end
 
   def test_translate_with_last_default_not_named_html
-    translation = translate(:'translations.missing', :default => [:'translations.missing_html', :'translations.foo'])
-    assert_equal 'Foo', translation
+    translation = translate(:'translations.missing', default: [:'translations.missing_html', :'translations.foo'])
+    assert_equal "Foo", translation
     assert_equal false, translation.html_safe?
   end
 
   def test_translate_with_string_default
-    translation = translate(:'translations.missing', default: 'A Generic String')
-    assert_equal 'A Generic String', translation
+    translation = translate(:'translations.missing', default: "A Generic String")
+    assert_equal "A Generic String", translation
   end
 
   def test_translate_with_object_default
@@ -214,13 +216,13 @@ class TranslationHelperTest < ActiveSupport::TestCase
   end
 
   def test_translate_with_array_of_string_defaults
-    translation = translate(:'translations.missing', default: ['A Generic String', 'Second generic string'])
-    assert_equal 'A Generic String', translation
+    translation = translate(:'translations.missing', default: ["A Generic String", "Second generic string"])
+    assert_equal "A Generic String", translation
   end
 
   def test_translate_with_array_of_defaults_with_nil
-    translation = translate(:'translations.missing', default: [:'also_missing', nil, 'A Generic String'])
-    assert_equal 'A Generic String', translation
+    translation = translate(:'translations.missing', default: [:'also_missing', nil, "A Generic String"])
+    assert_equal "A Generic String", translation
   end
 
   def test_translate_with_array_of_array_default
diff --git a/actionview/test/template/url_helper_test.rb b/actionview/test/template/url_helper_test.rb
index ab56d80de3..0cd0386cac 100644
--- a/actionview/test/template/url_helper_test.rb
+++ b/actionview/test/template/url_helper_test.rb
@@ -1,15 +1,15 @@
-require 'abstract_unit'
+# frozen_string_literal: true
 
-class UrlHelperTest < ActiveSupport::TestCase
+require "abstract_unit"
 
+class UrlHelperTest < ActiveSupport::TestCase
   # In a few cases, the helper proxies to 'controller'
   # or request.
   #
   # In those cases, we'll set up a simple mock
   attr_accessor :controller, :request
 
-  cattr_accessor :request_forgery
-  self.request_forgery = false
+  cattr_accessor :request_forgery, default: false
 
   routes = ActionDispatch::Routing::RouteSet.new
   routes.draw do
@@ -17,6 +17,10 @@ class UrlHelperTest < ActiveSupport::TestCase
     get "/other" => "foo#other"
     get "/article/:id" => "foo#article", :as => :article
     get "/category/:category" => "foo#category"
+
+    scope :engine do
+      get "/" => "foo#bar"
+    end
   end
 
   include ActionView::Helpers::UrlHelper
@@ -43,59 +47,59 @@ class UrlHelperTest < ActiveSupport::TestCase
   end
 
   def test_url_for_with_back
-    referer = 'http://www.example.com/referer'
+    referer = "http://www.example.com/referer"
     @controller = Struct.new(:request).new(Struct.new(:env).new("HTTP_REFERER" => referer))
 
-    assert_equal 'http://www.example.com/referer', url_for(:back)
+    assert_equal "http://www.example.com/referer", url_for(:back)
   end
 
   def test_url_for_with_back_and_no_referer
     @controller = Struct.new(:request).new(Struct.new(:env).new({}))
-    assert_equal 'javascript:history.back()', url_for(:back)
+    assert_equal "javascript:history.back()", url_for(:back)
   end
 
   def test_url_for_with_back_and_no_controller
     @controller = nil
-    assert_equal 'javascript:history.back()', url_for(:back)
+    assert_equal "javascript:history.back()", url_for(:back)
   end
 
   def test_url_for_with_back_and_javascript_referer
-    referer = 'javascript:alert(document.cookie)'
+    referer = "javascript:alert(document.cookie)"
     @controller = Struct.new(:request).new(Struct.new(:env).new("HTTP_REFERER" => referer))
-    assert_equal 'javascript:history.back()', url_for(:back)
+    assert_equal "javascript:history.back()", url_for(:back)
   end
 
   def test_url_for_with_invalid_referer
-    referer = 'THIS IS NOT A URL'
+    referer = "THIS IS NOT A URL"
     @controller = Struct.new(:request).new(Struct.new(:env).new("HTTP_REFERER" => referer))
-    assert_equal 'javascript:history.back()', url_for(:back)
+    assert_equal "javascript:history.back()", url_for(:back)
   end
 
   def test_to_form_params_with_hash
     assert_equal(
-      [{ name: :name, value: 'David' }, { name: :nationality, value: 'Danish' }],
-      to_form_params(name: 'David', nationality: 'Danish')
+      [{ name: :name, value: "David" }, { name: :nationality, value: "Danish" }],
+      to_form_params(name: "David", nationality: "Danish")
     )
   end
 
   def test_to_form_params_with_nested_hash
     assert_equal(
-      [{ name: 'country[name]', value: 'Denmark' }],
-      to_form_params(country: { name: 'Denmark' })
+      [{ name: "country[name]", value: "Denmark" }],
+      to_form_params(country: { name: "Denmark" })
     )
   end
 
   def test_to_form_params_with_array_nested_in_hash
     assert_equal(
-      [{ name: 'countries[]', value: 'Denmark' }, { name: 'countries[]', value: 'Sweden' }],
-      to_form_params(countries: ['Denmark', 'Sweden'])
+      [{ name: "countries[]", value: "Denmark" }, { name: "countries[]", value: "Sweden" }],
+      to_form_params(countries: ["Denmark", "Sweden"])
     )
   end
 
   def test_to_form_params_with_namespace
     assert_equal(
-      [{ name: 'country[name]', value: 'Denmark' }],
-      to_form_params({name: 'Denmark'}, 'country')
+      [{ name: "country[name]", value: "Denmark" }],
+      to_form_params({ name: "Denmark" }, "country")
     )
   end
 
@@ -122,11 +126,11 @@ class UrlHelperTest < ActiveSupport::TestCase
   end
 
   def test_button_to_with_form_class
-    assert_dom_equal %{<form method="post" action="http://www.example.com" class="custom-class"><input type="submit" value="Hello" /></form>}, button_to("Hello", "http://www.example.com", form_class: 'custom-class')
+    assert_dom_equal %{<form method="post" action="http://www.example.com" class="custom-class"><input type="submit" value="Hello" /></form>}, button_to("Hello", "http://www.example.com", form_class: "custom-class")
   end
 
   def test_button_to_with_form_class_escapes
-    assert_dom_equal %{<form method="post" action="http://www.example.com" class="&lt;script&gt;evil_js&lt;/script&gt;"><input type="submit" value="Hello" /></form>}, button_to("Hello", "http://www.example.com", form_class: '<script>evil_js</script>')
+    assert_dom_equal %{<form method="post" action="http://www.example.com" class="&lt;script&gt;evil_js&lt;/script&gt;"><input type="submit" value="Hello" /></form>}, button_to("Hello", "http://www.example.com", form_class: "<script>evil_js</script>")
   end
 
   def test_button_to_with_query
@@ -211,7 +215,7 @@ class UrlHelperTest < ActiveSupport::TestCase
   def test_button_to_with_block
     assert_dom_equal(
       %{<form method="post" action="http://www.example.com" class="button_to"><button type="submit"><span>Hello</span></button></form>},
-      button_to("http://www.example.com") { content_tag(:span, 'Hello') }
+      button_to("http://www.example.com") { content_tag(:span, "Hello") }
     )
   end
 
@@ -222,17 +226,48 @@ class UrlHelperTest < ActiveSupport::TestCase
     )
   end
 
+  class FakeParams
+    def initialize(permitted = true)
+      @permitted = permitted
+    end
+
+    def permitted?
+      @permitted
+    end
+
+    def to_h
+      if permitted?
+        { foo: :bar, baz: "quux" }
+      else
+        raise ArgumentError
+      end
+    end
+  end
+
+  def test_button_to_with_permitted_strong_params
+    assert_dom_equal(
+      %{<form action="http://www.example.com" class="button_to" method="post"><input type="submit" value="Hello" /><input type="hidden" name="baz" value="quux" /><input type="hidden" name="foo" value="bar" /></form>},
+      button_to("Hello", "http://www.example.com", params: FakeParams.new)
+    )
+  end
+
+  def test_button_to_with_unpermitted_strong_params
+    assert_raises(ArgumentError) do
+      button_to("Hello", "http://www.example.com", params: FakeParams.new(false))
+    end
+  end
+
   def test_button_to_with_nested_hash_params
     assert_dom_equal(
       %{<form action="http://www.example.com" class="button_to" method="post"><input type="submit" value="Hello" /><input type="hidden" name="foo[bar]" value="baz" /></form>},
-      button_to("Hello", "http://www.example.com", params: { foo: { bar: 'baz' } })
+      button_to("Hello", "http://www.example.com", params: { foo: { bar: "baz" } })
     )
   end
 
   def test_button_to_with_nested_array_params
     assert_dom_equal(
       %{<form action="http://www.example.com" class="button_to" method="post"><input type="submit" value="Hello" /><input type="hidden" name="foo[]" value="bar" /></form>},
-      button_to("Hello", "http://www.example.com", params: { foo: ['bar'] })
+      button_to("Hello", "http://www.example.com", params: { foo: ["bar"] })
     )
   end
 
@@ -241,13 +276,13 @@ class UrlHelperTest < ActiveSupport::TestCase
   end
 
   def test_link_tag_without_host_option
-    assert_dom_equal(%{<a href="/">Test Link</a>}, link_to('Test Link', url_hash))
+    assert_dom_equal(%{<a href="/">Test Link</a>}, link_to("Test Link", url_hash))
   end
 
   def test_link_tag_with_host_option
     hash = hash_for(host: "www.example.com")
     expected = %{<a href="http://www.example.com/">Test Link</a>}
-    assert_dom_equal(expected, link_to('Test Link', hash))
+    assert_dom_equal(expected, link_to("Test Link", hash))
   end
 
   def test_link_tag_with_query
@@ -261,15 +296,15 @@ class UrlHelperTest < ActiveSupport::TestCase
   end
 
   def test_link_tag_with_back
-    env = {"HTTP_REFERER" => "http://www.example.com/referer"}
+    env = { "HTTP_REFERER" => "http://www.example.com/referer" }
     @controller = Struct.new(:request).new(Struct.new(:env).new(env))
     expected = %{<a href="#{env["HTTP_REFERER"]}">go back</a>}
-    assert_dom_equal expected, link_to('go back', :back)
+    assert_dom_equal expected, link_to("go back", :back)
   end
 
   def test_link_tag_with_back_and_no_referer
     @controller = Struct.new(:request).new(Struct.new(:env).new({}))
-    link = link_to('go back', :back)
+    link = link_to("go back", :back)
     assert_dom_equal %{<a href="javascript:history.back()">go back</a>}, link
   end
 
@@ -329,7 +364,7 @@ class UrlHelperTest < ActiveSupport::TestCase
   def test_link_to_with_string_remote_in_non_html_options
     assert_dom_equal(
       %{<a href="/" data-remote="true">Hello</a>},
-      link_to("Hello", hash_for('remote' => true), {})
+      link_to("Hello", hash_for("remote" => true), {})
     )
   end
 
@@ -350,14 +385,14 @@ class UrlHelperTest < ActiveSupport::TestCase
   def test_link_tag_using_delete_javascript_and_href
     assert_dom_equal(
       %{<a href="\#" rel="nofollow" data-method="delete">Destroy</a>},
-      link_to("Destroy", "http://www.example.com", method: :delete, href: '#')
+      link_to("Destroy", "http://www.example.com", method: :delete, href: "#")
     )
   end
 
   def test_link_tag_using_post_javascript_and_rel
     assert_dom_equal(
       %{<a href="http://www.example.com" data-method="post" rel="example nofollow">Hello</a>},
-      link_to("Hello", "http://www.example.com", method: :post, rel: 'example')
+      link_to("Hello", "http://www.example.com", method: :post, rel: "example")
     )
   end
 
@@ -371,24 +406,24 @@ class UrlHelperTest < ActiveSupport::TestCase
   def test_link_tag_using_delete_javascript_and_href_and_confirm
     assert_dom_equal(
       %{<a href="\#" rel="nofollow" data-confirm="Are you serious?" data-method="delete">Destroy</a>},
-      link_to("Destroy", "http://www.example.com", method: :delete, href: '#', data: { confirm: "Are you serious?" })
+      link_to("Destroy", "http://www.example.com", method: :delete, href: "#", data: { confirm: "Are you serious?" })
     )
   end
 
   def test_link_tag_with_block
     assert_dom_equal %{<a href="/"><span>Example site</span></a>},
-      link_to('/') { content_tag(:span, 'Example site') }
+      link_to("/") { content_tag(:span, "Example site") }
   end
 
   def test_link_tag_with_block_and_html_options
     assert_dom_equal %{<a class="special" href="/"><span>Example site</span></a>},
-      link_to('/', class: "special") { content_tag(:span, 'Example site') }
+      link_to("/", class: "special") { content_tag(:span, "Example site") }
   end
 
   def test_link_tag_using_block_and_hash
     assert_dom_equal(
       %{<a href="/"><span>Example site</span></a>},
-      link_to(url_hash) { content_tag(:span, 'Example site') }
+      link_to(url_hash) { content_tag(:span, "Example site") }
     )
   end
 
@@ -452,7 +487,7 @@ class UrlHelperTest < ActiveSupport::TestCase
   end
 
   def test_current_page_with_http_head_method
-    @request = request_for_url("/", :method => :head)
+    @request = request_for_url("/", method: :head)
     assert current_page?(url_hash)
     assert current_page?("http://www.example.com/")
   end
@@ -470,6 +505,21 @@ class UrlHelperTest < ActiveSupport::TestCase
     assert current_page?("http://www.example.com/")
   end
 
+  def test_current_page_considering_params
+    @request = request_for_url("/?order=desc&page=1")
+
+    assert !current_page?(url_hash, check_parameters: true)
+    assert !current_page?(url_hash.merge(check_parameters: true))
+    assert !current_page?(ActionController::Parameters.new(url_hash.merge(check_parameters: true)).permit!)
+    assert !current_page?("http://www.example.com/", check_parameters: true)
+  end
+
+  def test_current_page_considering_params_when_options_does_not_respond_to_to_hash
+    @request = request_for_url("/?order=desc&page=1")
+
+    assert !current_page?(:back, check_parameters: false)
+  end
+
   def test_current_page_with_params_that_match
     @request = request_for_url("/?order=desc&page=1")
 
@@ -477,22 +527,22 @@ class UrlHelperTest < ActiveSupport::TestCase
     assert current_page?("http://www.example.com/?order=desc&page=1")
   end
 
-  def test_current_page_with_not_get_verb
-    @request = request_for_url("/events", method: :post)
+  def test_current_page_with_scope_that_match
+    @request = request_for_url("/engine/")
 
-    assert !current_page?('/events')
+    assert current_page?("/engine")
   end
 
   def test_current_page_with_escaped_params
     @request = request_for_url("/category/administra%c3%a7%c3%a3o")
 
-    assert current_page?(controller: 'foo', action: 'category', category: 'administração')
+    assert current_page?(controller: "foo", action: "category", category: "administração")
   end
 
   def test_current_page_with_escaped_params_with_different_encoding
     @request = request_for_url("/")
-    @request.stub(:path, "/category/administra%c3%a7%c3%a3o".force_encoding(Encoding::ASCII_8BIT)) do
-      assert current_page?(:controller => 'foo', :action => 'category', category: 'administração')
+    @request.stub(:path, "/category/administra%c3%a7%c3%a3o".dup.force_encoding(Encoding::ASCII_8BIT)) do
+      assert current_page?(controller: "foo", action: "category", category: "administração")
       assert current_page?("http://www.example.com/category/administra%c3%a7%c3%a3o")
     end
   end
@@ -500,7 +550,19 @@ class UrlHelperTest < ActiveSupport::TestCase
   def test_current_page_with_double_escaped_params
     @request = request_for_url("/category/administra%c3%a7%c3%a3o?callback_url=http%3a%2f%2fexample.com%2ffoo")
 
-    assert current_page?(controller: 'foo', action: 'category', category: 'administração', callback_url: 'http://example.com/foo')
+    assert current_page?(controller: "foo", action: "category", category: "administração", callback_url: "http://example.com/foo")
+  end
+
+  def test_current_page_with_trailing_slash
+    @request = request_for_url("/posts")
+
+    assert current_page?("/posts/")
+  end
+
+  def test_current_page_with_not_get_verb
+    @request = request_for_url("/events", method: :post)
+
+    assert !current_page?("/events")
   end
 
   def test_link_unless_current
@@ -521,7 +583,7 @@ class UrlHelperTest < ActiveSupport::TestCase
     @request = request_for_url("/?order=desc&page=1")
 
     assert_equal "Showing",
-      link_to_unless_current("Showing", hash_for(order: 'desc', page: '1'))
+      link_to_unless_current("Showing", hash_for(order: "desc", page: "1"))
     assert_equal "Showing",
       link_to_unless_current("Showing", "http://www.example.com/?order=desc&page=1")
 
@@ -564,8 +626,8 @@ class UrlHelperTest < ActiveSupport::TestCase
 
   def test_mail_to_with_special_characters
     assert_dom_equal(
-      %{<a href="mailto:%23%21%24%25%26%27%2A%2B-%2F%3D%3F%5E_%60%7B%7D%7C%7E@example.org">#!$%&amp;&#39;*+-/=?^_`{}|~@example.org</a>},
-      mail_to("#!$%&'*+-/=?^_`{}|~@example.org")
+      %{<a href="mailto:%23%21%24%25%26%27%2A%2B-%2F%3D%3F%5E_%60%7B%7D%7C@example.org">#!$%&amp;&#39;*+-/=?^_`{}|@example.org</a>},
+      mail_to("#!$%&'*+-/=?^_`{}|@example.org")
     )
   end
 
@@ -577,13 +639,13 @@ class UrlHelperTest < ActiveSupport::TestCase
 
     assert_dom_equal(
       %{<a href="mailto:me@example.com?body=This%20is%20the%20body%20of%20the%20message.&amp;subject=This%20is%20an%20example%20email">My email</a>},
-      mail_to("me@example.com", "My email", cc: '', bcc: '', subject: "This is an example email", body: "This is the body of the message.")
+      mail_to("me@example.com", "My email", cc: "", bcc: "", subject: "This is an example email", body: "This is the body of the message.")
     )
   end
 
   def test_mail_to_with_img
     assert_dom_equal %{<a href="mailto:feedback@example.com"><img src="/feedback.png" /></a>},
-      mail_to('feedback@example.com', raw('<img src="/feedback.png" />'))
+      mail_to("feedback@example.com", raw('<img src="/feedback.png" />'))
   end
 
   def test_mail_to_with_html_safe_string
@@ -606,22 +668,22 @@ class UrlHelperTest < ActiveSupport::TestCase
 
   def test_mail_to_with_block
     assert_dom_equal %{<a href="mailto:me@example.com"><span>Email me</span></a>},
-      mail_to('me@example.com') { content_tag(:span, 'Email me') }
+      mail_to("me@example.com") { content_tag(:span, "Email me") }
   end
 
   def test_mail_to_with_block_and_options
     assert_dom_equal %{<a class="special" href="mailto:me@example.com?cc=ccaddress%40example.com"><span>Email me</span></a>},
-      mail_to('me@example.com', cc: "ccaddress@example.com", class: "special") { content_tag(:span, 'Email me') }
+      mail_to("me@example.com", cc: "ccaddress@example.com", class: "special") { content_tag(:span, "Email me") }
   end
 
   def test_mail_to_does_not_modify_html_options_hash
-    options = { class: 'special' }
-    mail_to 'me@example.com', 'ME!', options
-    assert_equal({ class: 'special' }, options)
+    options = { class: "special" }
+    mail_to "me@example.com", "ME!", options
+    assert_equal({ class: "special" }, options)
   end
 
   def protect_against_forgery?
-    self.request_forgery
+    request_forgery
   end
 
   def form_authenticity_token(*args)
@@ -631,46 +693,39 @@ class UrlHelperTest < ActiveSupport::TestCase
   def request_forgery_protection_token
     "form_token"
   end
-
-  private
-    def sort_query_string_params(uri)
-      path, qs = uri.split('?')
-      qs = qs.split('&amp;').sort.join('&amp;') if qs
-      qs ? "#{path}?#{qs}" : path
-    end
 end
 
 class UrlHelperControllerTest < ActionController::TestCase
   class UrlHelperController < ActionController::Base
     test_routes do
-      get 'url_helper_controller_test/url_helper/show/:id',
-        to: 'url_helper_controller_test/url_helper#show',
+      get "url_helper_controller_test/url_helper/show/:id",
+        to: "url_helper_controller_test/url_helper#show",
         as: :show
 
-      get 'url_helper_controller_test/url_helper/profile/:name',
-        to: 'url_helper_controller_test/url_helper#show',
+      get "url_helper_controller_test/url_helper/profile/:name",
+        to: "url_helper_controller_test/url_helper#show",
         as: :profile
 
-      get 'url_helper_controller_test/url_helper/show_named_route',
-        to: 'url_helper_controller_test/url_helper#show_named_route',
+      get "url_helper_controller_test/url_helper/show_named_route",
+        to: "url_helper_controller_test/url_helper#show_named_route",
         as: :show_named_route
 
       ActiveSupport::Deprecation.silence do
         get "/:controller(/:action(/:id))"
       end
 
-      get 'url_helper_controller_test/url_helper/normalize_recall_params',
+      get "url_helper_controller_test/url_helper/normalize_recall_params",
         to: UrlHelperController.action(:normalize_recall),
         as: :normalize_recall_params
 
-      get '/url_helper_controller_test/url_helper/override_url_helper/default',
-        to: 'url_helper_controller_test/url_helper#override_url_helper',
+      get "/url_helper_controller_test/url_helper/override_url_helper/default",
+        to: "url_helper_controller_test/url_helper#override_url_helper",
         as: :override_url_helper
     end
 
     def show
       if params[:name]
-        render inline: 'ok'
+        render inline: "ok"
       else
         redirect_to profile_path(params[:id])
       end
@@ -685,23 +740,23 @@ class UrlHelperControllerTest < ActionController::TestCase
     end
 
     def nil_url_for
-      render inline: '<%= url_for(nil) %>'
+      render inline: "<%= url_for(nil) %>"
     end
 
     def normalize_recall_params
-      render inline: '<%= normalize_recall_params_path %>'
+      render inline: "<%= normalize_recall_params_path %>"
     end
 
     def recall_params_not_changed
-      render inline: '<%= url_for(action: :show_url_for) %>'
+      render inline: "<%= url_for(action: :show_url_for) %>"
     end
 
     def override_url_helper
-      render inline: '<%= override_url_helper_path %>'
+      render inline: "<%= override_url_helper_path %>"
     end
 
     def override_url_helper_path
-      '/url_helper_controller_test/url_helper/override_url_helper/override'
+      "/url_helper_controller_test/url_helper/override_url_helper/override"
     end
     helper_method :override_url_helper_path
   end
@@ -710,58 +765,58 @@ class UrlHelperControllerTest < ActionController::TestCase
 
   def test_url_for_shows_only_path
     get :show_url_for
-    assert_equal '/url_helper_controller_test/url_helper/show_url_for', @response.body
+    assert_equal "/url_helper_controller_test/url_helper/show_url_for", @response.body
   end
 
   def test_named_route_url_shows_host_and_path
-    get :show_named_route, params: { kind: 'url' }
-    assert_equal 'http://test.host/url_helper_controller_test/url_helper/show_named_route',
+    get :show_named_route, params: { kind: "url" }
+    assert_equal "http://test.host/url_helper_controller_test/url_helper/show_named_route",
       @response.body
   end
 
   def test_named_route_path_shows_only_path
-    get :show_named_route, params: { kind: 'path' }
-    assert_equal '/url_helper_controller_test/url_helper/show_named_route', @response.body
+    get :show_named_route, params: { kind: "path" }
+    assert_equal "/url_helper_controller_test/url_helper/show_named_route", @response.body
   end
 
   def test_url_for_nil_returns_current_path
     get :nil_url_for
-    assert_equal '/url_helper_controller_test/url_helper/nil_url_for', @response.body
+    assert_equal "/url_helper_controller_test/url_helper/nil_url_for", @response.body
   end
 
   def test_named_route_should_show_host_and_path_using_controller_default_url_options
     class << @controller
       def default_url_options
-        { host: 'testtwo.host' }
+        { host: "testtwo.host" }
       end
     end
 
-    get :show_named_route, params: { kind: 'url' }
-    assert_equal 'http://testtwo.host/url_helper_controller_test/url_helper/show_named_route', @response.body
+    get :show_named_route, params: { kind: "url" }
+    assert_equal "http://testtwo.host/url_helper_controller_test/url_helper/show_named_route", @response.body
   end
 
   def test_recall_params_should_be_normalized
     get :normalize_recall_params
-    assert_equal '/url_helper_controller_test/url_helper/normalize_recall_params', @response.body
+    assert_equal "/url_helper_controller_test/url_helper/normalize_recall_params", @response.body
   end
 
   def test_recall_params_should_not_be_changed
     get :recall_params_not_changed
-    assert_equal '/url_helper_controller_test/url_helper/show_url_for', @response.body
+    assert_equal "/url_helper_controller_test/url_helper/show_url_for", @response.body
   end
 
   def test_recall_params_should_normalize_id
-    get :show, params: { id: '123' }
+    get :show, params: { id: "123" }
     assert_equal 302, @response.status
-    assert_equal 'http://test.host/url_helper_controller_test/url_helper/profile/123', @response.location
+    assert_equal "http://test.host/url_helper_controller_test/url_helper/profile/123", @response.location
 
-    get :show, params: { name: '123' }
-    assert_equal 'ok', @response.body
+    get :show, params: { name: "123" }
+    assert_equal "ok", @response.body
   end
 
   def test_url_helper_can_be_overridden
     get :override_url_helper
-    assert_equal '/url_helper_controller_test/url_helper/override_url_helper/override', @response.body
+    assert_equal "/url_helper_controller_test/url_helper/override_url_helper/override", @response.body
   end
 end
 
@@ -778,9 +833,9 @@ class TasksController < ActionController::Base
     render_default
   end
 
-  protected
+  private
     def render_default
-      render inline: "<%= link_to_unless_current('tasks', tasks_path) %>\n" +
+      render inline: "<%= link_to_unless_current('tasks', tasks_path) %>\n" \
         "<%= link_to_unless_current('tasks', tasks_url) %>"
     end
 end
@@ -835,6 +890,11 @@ class WorkshopsController < ActionController::Base
     @workshop = Workshop.new(params[:id])
     render inline: "<%= url_for(@workshop) %>\n<%= link_to('Workshop', @workshop) %>"
   end
+
+  def edit
+    @workshop = Workshop.new(params[:id])
+    render inline: "<%= current_page?(@workshop) %>"
+  end
 end
 
 class SessionsController < ActionController::Base
@@ -899,4 +959,11 @@ class PolymorphicControllerTest < ActionController::TestCase
     get :edit, params: { workshop_id: 1, id: 1, format: "json"  }
     assert_equal %{/workshops/1/sessions/1.json\n<a href="/workshops/1/sessions/1.json">Session</a>}, @response.body
   end
+
+  def test_current_page_when_options_does_not_respond_to_to_hash
+    @controller = WorkshopsController.new
+
+    get :edit, params: { id: 1 }
+    assert_equal "false", @response.body
+  end
 end
diff --git a/actionview/test/tmp/.gitkeep b/actionview/test/tmp/.keep
index e69de29bb2..e69de29bb2 100644
--- a/actionview/test/tmp/.gitkeep
+++ b/actionview/test/tmp/.keep
diff --git a/actionview/test/ujs/.gitignore b/actionview/test/ujs/.gitignore
new file mode 100644
index 0000000000..31dbbff57c
--- /dev/null
+++ b/actionview/test/ujs/.gitignore
@@ -0,0 +1 @@
+/log
diff --git a/actionview/test/ujs/config.ru b/actionview/test/ujs/config.ru
new file mode 100644
index 0000000000..7cd3a16acb
--- /dev/null
+++ b/actionview/test/ujs/config.ru
@@ -0,0 +1,6 @@
+# frozen_string_literal: true
+
+$LOAD_PATH.unshift __dir__
+require "server"
+
+run UJS::Server
diff --git a/actionview/test/ujs/public/test/.eslintrc.yml b/actionview/test/ujs/public/test/.eslintrc.yml
new file mode 100644
index 0000000000..06d7dd36ea
--- /dev/null
+++ b/actionview/test/ujs/public/test/.eslintrc.yml
@@ -0,0 +1,21 @@
+env:
+  browser: true
+extends: eslint:recommended
+rules:
+  no-undef: off
+  no-unused-vars: off
+  indent: off
+  linebreak-style: ['error', 'unix']
+  quotes: ['error', 'single']
+  semi: ['error', 'never']
+  no-shadow: ['error'] # Prevent potential errors
+  no-console: 'off'
+  # styles
+  space-before-function-paren: ['error', 'never']
+  space-before-blocks: 'error'
+  brace-style: ['error', '1tbs', { allowSingleLine: true }]
+  key-spacing: 'error'
+  array-bracket-spacing: 'error'
+  comma-spacing: 'error'
+  comma-dangle: 'off'
+  eol-last: 'error'
diff --git a/actionview/test/ujs/public/test/call-ajax.js b/actionview/test/ujs/public/test/call-ajax.js
new file mode 100644
index 0000000000..49e64cad5c
--- /dev/null
+++ b/actionview/test/ujs/public/test/call-ajax.js
@@ -0,0 +1,27 @@
+(function() {
+
+module('call-ajax', {
+  setup: function() {
+    $('#qunit-fixture')
+      .append($('<a />', { href: '#' }))
+  }
+})
+
+asyncTest('call ajax without "ajax:beforeSend"', 1, function() {
+
+  var link = $('#qunit-fixture a')
+  link.bindNative('click', function() {
+    Rails.ajax({
+      type: 'get',
+      url: '/',
+      success: function() {
+        ok(true, 'calling request in ajax:success')
+      }
+    })
+  })
+
+  link.triggerNative('click')
+  setTimeout(function() { start() }, 13)
+})
+
+})()
diff --git a/actionview/test/ujs/public/test/call-remote-callbacks.js b/actionview/test/ujs/public/test/call-remote-callbacks.js
new file mode 100644
index 0000000000..48763f6301
--- /dev/null
+++ b/actionview/test/ujs/public/test/call-remote-callbacks.js
@@ -0,0 +1,239 @@
+(function() {
+
+module('call-remote-callbacks', {
+  setup: function() {
+    $('#qunit-fixture').append($('<form />', {
+      action: '/echo', method: 'get', 'data-remote': 'true'
+    }))
+  },
+  teardown: function() {
+    $(document).undelegate('form[data-remote]', 'ajax:beforeSend')
+    $(document).undelegate('form[data-remote]', 'ajax:before')
+    $(document).undelegate('form[data-remote]', 'ajax:send')
+    $(document).undelegate('form[data-remote]', 'ajax:complete')
+    $(document).undelegate('form[data-remote]', 'ajax:success')
+    $(document).unbind('iframe:loading')
+  }
+})
+
+function submit(fn) {
+  var form = $('form')
+
+  if (fn) fn(form)
+  form.triggerNative('submit')
+
+  setTimeout(function() { start() }, 13)
+}
+
+asyncTest('modifying form fields with "ajax:before" sends modified data in request', 3, function() {
+  $('form[data-remote]')
+    .append($('<input type="text" name="user_name" value="john">'))
+    .append($('<input type="text" name="removed_user_name" value="john">'))
+    .bindNative('ajax:before', function() {
+      var form = $(this)
+      form
+        .append($('<input />', {name: 'other_user_name', value: 'jonathan'}))
+        .find('input[name="removed_user_name"]').remove()
+      form
+        .find('input[name="user_name"]').val('steve')
+    })
+
+  submit(function(form) {
+    form.bindNative('ajax:success', function(e, data, status, xhr) {
+      equal(data.params.user_name, 'steve', 'modified field value should have been submitted')
+      equal(data.params.other_user_name, 'jonathan', 'added field value should have been submitted')
+      equal(data.params.removed_user_name, undefined, 'removed field value should be undefined')
+    })
+  })
+})
+
+asyncTest('modifying data("type") with "ajax:before" requests new dataType in request', 1, function() {
+  $('form[data-remote]').data('type', 'html')
+    .bindNative('ajax:before', function() {
+      this.setAttribute('data-type', 'xml')
+    })
+
+  submit(function(form) {
+    form.bindNative('ajax:beforeSend', function(e, xhr, settings) {
+      equal(settings.dataType, 'xml', 'modified dataType should have been requested')
+    })
+  })
+})
+
+asyncTest('setting data("with-credentials",true) with "ajax:before" uses new setting in request', 1, function() {
+  $('form[data-remote]').data('with-credentials', false)
+    .bindNative('ajax:before', function() {
+      this.setAttribute('data-with-credentials', true)
+    })
+
+  submit(function(form) {
+    form.bindNative('ajax:beforeSend', function(e, xhr, settings) {
+      equal(settings.withCredentials, true, 'setting modified in ajax:before should have forced withCredentials request')
+    })
+  })
+})
+
+asyncTest('stopping the "ajax:beforeSend" event aborts the request', 1, function() {
+  submit(function(form) {
+    form.bindNative('ajax:beforeSend', function() {
+      ok(true, 'aborting request in ajax:beforeSend')
+      return false
+    })
+    form.unbind('ajax:send').bindNative('ajax:send', function() {
+      ok(false, 'ajax:send should not run')
+    })
+    form.bindNative('ajax:error', function(e, response, status, xhr) {
+      ok(false, 'ajax:error should not run')
+    })
+    form.bindNative('ajax:complete', function() {
+      ok(false, 'ajax:complete should not run')
+    })
+  })
+})
+
+function skipIt() {
+  // This test cannot work due to the security feature in browsers which makes the value
+  // attribute of file input fields readonly, so it cannot be set with default value.
+  // This is what the test would look like though if browsers let us automate this test.
+  asyncTest('non-blank file form input field should abort remote request, but submit normally', 5, function() {
+    var form = $('form[data-remote]')
+          .append($('<input type="file" name="attachment" value="default.png">'))
+          .bindNative('ajax:beforeSend', function() {
+            ok(false, 'ajax:beforeSend should not run')
+          })
+          .bind('iframe:loading', function() {
+            ok(true, 'form should get submitted')
+          })
+          .bindNative('ajax:aborted:file', function(e, data) {
+            ok(data.length == 1, 'ajax:aborted:file event is passed all non-blank file inputs (jQuery objects)')
+            ok(data.first().is('input[name="attachment"]'), 'ajax:aborted:file adds non-blank file input to data')
+            ok(true, 'ajax:aborted:file event should run')
+          })
+          .triggerNative('submit')
+
+    setTimeout(function() {
+      form.find('input[type="file"]').val('')
+      form.unbind('ajax:beforeSend')
+      submit()
+    }, 13)
+  })
+
+  asyncTest('file form input field should not abort remote request if file form input does not have a name attribute', 5, function() {
+    var form = $('form[data-remote]')
+          .append($('<input type="file" value="default.png">'))
+          .bindNative('ajax:beforeSend', function() {
+            ok(true, 'ajax:beforeSend should run')
+          })
+          .bind('iframe:loading', function() {
+            ok(true, 'form should get submitted')
+          })
+          .bindNative('ajax:aborted:file', function(e, data) {
+            ok(false, 'ajax:aborted:file should not run')
+          })
+          .triggerNative('submit')
+
+    setTimeout(function() {
+      form.find('input[type="file"]').val('')
+      form.unbind('ajax:beforeSend')
+      submit()
+    }, 13)
+  })
+
+  asyncTest('blank file input field should abort request entirely if handler bound to "ajax:aborted:file" event that returns false', 1, function() {
+    var form = $('form[data-remote]')
+          .append($('<input type="file" name="attachment" value="default.png">'))
+          .bindNative('ajax:beforeSend', function() {
+            ok(false, 'ajax:beforeSend should not run')
+          })
+          .bind('iframe:loading', function() {
+            ok(false, 'form should not get submitted')
+          })
+          .bindNative('ajax:aborted:file', function() {
+            return false
+          })
+          .triggerNative('submit')
+
+    setTimeout(function() {
+      form.find('input[type="file"]').val('')
+      form.unbind('ajax:beforeSend')
+      submit()
+    }, 13)
+  })
+}
+
+asyncTest('"ajax:beforeSend" can be observed and stopped with event delegation', 1, function() {
+  $(document).delegate('form[data-remote]', 'ajax:beforeSend', function() {
+    ok(true, 'ajax:beforeSend observed with event delegation')
+    return false
+  })
+
+  submit(function(form) {
+    form.unbind('ajax:send').bindNative('ajax:send', function() {
+      ok(false, 'ajax:send should not run')
+    })
+    form.bindNative('ajax:complete', function() {
+      ok(false, 'ajax:complete should not run')
+    })
+  })
+})
+
+asyncTest('"ajax:beforeSend", "ajax:send", "ajax:success" and "ajax:complete" are triggered', 8, function() {
+  submit(function(form) {
+    form.bindNative('ajax:beforeSend', function(e, xhr, settings) {
+      ok(xhr.setRequestHeader, 'first argument to "ajax:beforeSend" should be an XHR object')
+      equal(settings.url, '/echo', 'second argument to "ajax:beforeSend" should be a settings object')
+    })
+    form.bindNative('ajax:send', function(e, xhr) {
+      ok(xhr.abort, 'first argument to "ajax:send" should be an XHR object')
+    })
+    form.bindNative('ajax:success', function(e, data, status, xhr) {
+      ok(data.REQUEST_METHOD, 'first argument to ajax:success should be a data object')
+      equal(status, 'OK', 'second argument to ajax:success should be a status string')
+      ok(xhr.getResponseHeader, 'third argument to "ajax:success" should be an XHR object')
+    })
+    form.bindNative('ajax:complete', function(e, xhr, status) {
+      ok(xhr.getResponseHeader, 'first argument to "ajax:complete" should be an XHR object')
+      equal(status, 'OK', 'second argument to ajax:complete should be a status string')
+    })
+  })
+})
+
+asyncTest('"ajax:beforeSend", "ajax:send", "ajax:error" and "ajax:complete" are triggered on error', 8, function() {
+  submit(function(form) {
+    form.attr('action', '/error')
+    form.bindNative('ajax:beforeSend', function(arg) { ok(true, 'ajax:beforeSend') })
+    form.bindNative('ajax:send', function(arg) { ok(true, 'ajax:send') })
+    form.bindNative('ajax:error', function(e, response, status, xhr) {
+      equal(response, '', 'first argument to ajax:error should be an HTTP status response')
+      equal(status, 'Forbidden', 'second argument to ajax:error should be a status string')
+      ok(xhr.getResponseHeader, 'third argument to "ajax:error" should be an XHR object')
+      // Opera returns "0" for HTTP code
+      equal(xhr.status, window.opera ? 0 : 403, 'status code should be 403')
+    })
+    form.bindNative('ajax:complete', function(e, xhr, status) {
+      ok(xhr.getResponseHeader, 'first argument to "ajax:complete" should be an XHR object')
+      equal(status, 'Forbidden', 'second argument to ajax:complete should be a status string')
+    })
+  })
+})
+
+asyncTest('binding to ajax callbacks via .delegate() triggers handlers properly', 4, function() {
+  $(document)
+    .delegate('form[data-remote]', 'ajax:beforeSend', function() {
+      ok(true, 'ajax:beforeSend handler is triggered')
+    })
+    .delegate('form[data-remote]', 'ajax:send', function() {
+      ok(true, 'ajax:send handler is triggered')
+    })
+    .delegate('form[data-remote]', 'ajax:success', function() {
+      ok(true, 'ajax:success handler is triggered')
+    })
+    .delegate('form[data-remote]', 'ajax:complete', function() {
+      ok(true, 'ajax:complete handler is triggered')
+    })
+  $('form[data-remote]').triggerNative('submit')
+
+  setTimeout(function() { start() }, 13)
+})
+
+})()
diff --git a/actionview/test/ujs/public/test/call-remote.js b/actionview/test/ujs/public/test/call-remote.js
new file mode 100644
index 0000000000..5932195363
--- /dev/null
+++ b/actionview/test/ujs/public/test/call-remote.js
@@ -0,0 +1,275 @@
+(function() {
+
+function buildForm(attrs) {
+  attrs = $.extend({ action: '/echo', 'data-remote': 'true' }, attrs)
+
+  $('#qunit-fixture').append($('<form />', attrs))
+    .find('form').append($('<input type="text" name="user_name" value="john">'))
+}
+
+module('call-remote')
+
+function submit(fn) {
+  $('form')
+    .bindNative('ajax:success', fn)
+    .bindNative('ajax:complete', function() { start() })
+    .triggerNative('submit')
+}
+
+asyncTest('form method is read from "method" and not from "data-method"', 1, function() {
+  buildForm({ method: 'post', 'data-method': 'get' })
+
+  submit(function(e, data, status, xhr) {
+    App.assertPostRequest(data)
+  })
+})
+
+asyncTest('form method is not read from "data-method" attribute in case of missing "method"', 1, function() {
+  buildForm({ 'data-method': 'put' })
+
+  submit(function(e, data, status, xhr) {
+    App.assertGetRequest(data)
+  })
+})
+
+asyncTest('form method is read from submit button "formmethod" if submit is triggered by that button', 1, function() {
+  var submitButton = $('<input type="submit" formmethod="get">')
+  buildForm({ method: 'post' })
+
+  $('#qunit-fixture').find('form').append(submitButton)
+    .bindNative('ajax:success', function(e, data, status, xhr) {
+      App.assertGetRequest(data)
+    })
+    .bindNative('ajax:complete', function() { start() })
+
+  submitButton.triggerNative('click')
+})
+
+asyncTest('form default method is GET', 1, function() {
+  buildForm()
+
+  submit(function(e, data, status, xhr) {
+    App.assertGetRequest(data)
+  })
+})
+
+asyncTest('form url is picked up from "action"', 1, function() {
+  buildForm({ method: 'post' })
+
+  submit(function(e, data, status, xhr) {
+    App.assertRequestPath(data, '/echo')
+  })
+})
+
+asyncTest('form url is read from "action" not "href"', 1, function() {
+  buildForm({ method: 'post', href: '/echo2' })
+
+  submit(function(e, data, status, xhr) {
+    App.assertRequestPath(data, '/echo')
+  })
+})
+
+asyncTest('form url is read from submit button "formaction" if submit is triggered by that button', 1, function() {
+  var submitButton = $('<input type="submit" formaction="/echo">')
+  buildForm({ method: 'post', href: '/echo2' })
+
+  $('#qunit-fixture').find('form').append(submitButton)
+    .bindNative('ajax:success', function(e, data, status, xhr) {
+      App.assertRequestPath(data, '/echo')
+    })
+    .bindNative('ajax:complete', function() { start() })
+
+  submitButton.triggerNative('click')
+})
+
+asyncTest('prefer JS, but accept any format', 1, function() {
+  buildForm({ method: 'post' })
+
+  submit(function(e, data, status, xhr) {
+    var accept = data.HTTP_ACCEPT
+    ok(accept.match(/text\/javascript.+\*\/\*/), 'Accept: ' + accept)
+  })
+})
+
+asyncTest('JS code should be executed', 1, function() {
+  buildForm({ method: 'post', 'data-type': 'script' })
+
+  $('form').append('<input type="text" name="content_type" value="text/javascript">')
+  $('form').append('<input type="text" name="content" value="ok(true, \'remote code should be run\')">')
+
+  submit()
+})
+
+asyncTest('ecmascript code should be executed', 1, function() {
+  buildForm({ method: 'post', 'data-type': 'script' })
+
+  $('form').append('<input type="text" name="content_type" value="application/ecmascript">')
+  $('form').append('<input type="text" name="content" value="ok(true, \'remote code should be run\')">')
+
+  submit()
+})
+
+asyncTest('execution of JS code does not modify current DOM', 1, function() {
+  var docLength, newDocLength
+  function getDocLength() {
+    return document.documentElement.outerHTML.length
+  }
+
+  buildForm({ method: 'post', 'data-type': 'script' })
+
+  $('form').append('<input type="text" name="content_type" value="text/javascript">')
+  $('form').append('<input type="text" name="content" value="\'remote code should be run\'">')
+
+  docLength = getDocLength()
+
+  submit(function() {
+    newDocLength = getDocLength()
+    ok(docLength === newDocLength, 'executed JS should not present in the document')
+  })
+})
+
+asyncTest('XML document should be parsed', 1, function() {
+  buildForm({ method: 'post', 'data-type': 'html' })
+
+  $('form').append('<input type="text" name="content_type" value="application/xml">')
+  $('form').append('<input type="text" name="content" value="<p>hello</p>">')
+
+  submit(function(e, data, status, xhr) {
+    ok(data instanceof Document, 'returned data should be an XML document')
+  })
+})
+
+asyncTest('accept application/json if "data-type" is json', 1, function() {
+  buildForm({ method: 'post', 'data-type': 'json' })
+
+  submit(function(e, data, status, xhr) {
+    equal(data.HTTP_ACCEPT, 'application/json, text/javascript, */*; q=0.01')
+  })
+})
+
+asyncTest('allow empty "data-remote" attribute', 1, function() {
+  var form = $('#qunit-fixture').append($('<form action="/echo" data-remote />')).find('form')
+
+  submit(function() {
+    ok(true, 'form with empty "data-remote" attribute is also allowed')
+  })
+})
+
+asyncTest('query string in form action should be stripped in a GET request in normal submit', 1, function() {
+  buildForm({ action: '/echo?param1=abc', 'data-remote': 'false' })
+
+  $(document).one('iframe:loaded', function(e, data) {
+    equal(data.params.param1, undefined, '"param1" should not be passed to server')
+    start()
+  })
+
+  $('#qunit-fixture form').triggerNative('submit')
+})
+
+asyncTest('query string in form action should be stripped in a GET request in ajax submit', 1, function() {
+  buildForm({ action: '/echo?param1=abc' })
+
+  submit(function(e, data, status, xhr) {
+    equal(data.params.param1, undefined, '"param1" should not be passed to server')
+  })
+})
+
+asyncTest('query string in form action should not be stripped in a POST request in normal submit', 1, function() {
+  buildForm({ action: '/echo?param1=abc', method: 'post', 'data-remote': 'false' })
+
+  $(document).one('iframe:loaded', function(e, data) {
+    equal(data.params.param1, 'abc', '"param1" should be passed to server')
+    start()
+  })
+
+  $('#qunit-fixture form').triggerNative('submit')
+})
+
+asyncTest('query string in form action should not be stripped in a POST request in ajax submit', 1, function() {
+  buildForm({ action: '/echo?param1=abc', method: 'post' })
+
+  submit(function(e, data, status, xhr) {
+    equal(data.params.param1, 'abc', '"param1" should be passed to server')
+  })
+})
+
+asyncTest('allow empty form "action"', 1, function() {
+  var currentLocation, ajaxLocation
+
+  buildForm({ action: '' })
+
+  $('#qunit-fixture').find('form')
+    .bindNative('ajax:beforeSend', function(e, xhr, settings) {
+      // Get current location (the same way jQuery does)
+      try {
+        currentLocation = location.href
+      } catch(err) {
+        currentLocation = document.createElement( 'a' )
+        currentLocation.href = ''
+        currentLocation = currentLocation.href
+      }
+      currentLocation = currentLocation.replace(/\?.*$/, '')
+
+      // Actual location (strip out settings.data that jQuery serializes and appends)
+      // HACK: can no longer use settings.data below to see what was appended to URL, as of
+      // jQuery 1.6.3 (see http://bugs.jquery.com/ticket/10202 and https://github.com/jquery/jquery/pull/544)
+      ajaxLocation = settings.url.replace('user_name=john', '').replace(/&$/, '').replace(/\?$/, '')
+      equal(ajaxLocation.match(/^(.*)/)[1], currentLocation, 'URL should be current page by default')
+
+      // Prevent the request from actually getting sent to the current page and
+      // causing an error.
+      return false
+    })
+    .triggerNative('submit')
+
+  setTimeout(function() { start() }, 13)
+})
+
+asyncTest('sends CSRF token in custom header', 1, function() {
+  buildForm({ method: 'post' })
+  $('#qunit-fixture').append('<meta name="csrf-token" content="cf50faa3fe97702ca1ae" />')
+
+  submit(function(e, data, status, xhr) {
+    equal(data.HTTP_X_CSRF_TOKEN, 'cf50faa3fe97702ca1ae', 'X-CSRF-Token header should be sent')
+  })
+})
+
+asyncTest('intelligently guesses crossDomain behavior when target URL has a different protocol and/or hostname', 1, function() {
+
+  // Don't set data-cross-domain here, just set action to be a different domain than localhost
+  buildForm({ action: 'http://www.alfajango.com' })
+  $('#qunit-fixture').append('<meta name="csrf-token" content="cf50faa3fe97702ca1ae" />')
+
+  $('#qunit-fixture').find('form')
+    .bindNative('ajax:beforeSend', function(evt, req, settings) {
+
+      equal(settings.crossDomain, true, 'crossDomain should be set to true')
+
+      // prevent request from actually getting sent off-domain
+      return false
+    })
+    .triggerNative('submit')
+
+  setTimeout(function() { start() }, 13)
+})
+
+asyncTest('intelligently guesses crossDomain behavior when target URL consists of only a path', 1, function() {
+
+  // Don't set data-cross-domain here, just set action to be a different domain than localhost
+  buildForm({ action: '/just/a/path' })
+  $('#qunit-fixture').append('<meta name="csrf-token" content="cf50faa3fe97702ca1ae" />')
+
+  $('#qunit-fixture').find('form')
+    .bindNative('ajax:beforeSend', function(evt, req, settings) {
+
+      equal(settings.crossDomain, false, 'crossDomain should be set to false')
+
+      // prevent request from actually getting sent off-domain
+      return false
+    })
+    .triggerNative('submit')
+
+  setTimeout(function() { start() }, 13)
+})
+
+})()
diff --git a/actionview/test/ujs/public/test/csrf-refresh.js b/actionview/test/ujs/public/test/csrf-refresh.js
new file mode 100644
index 0000000000..e302042542
--- /dev/null
+++ b/actionview/test/ujs/public/test/csrf-refresh.js
@@ -0,0 +1,24 @@
+(function() {
+
+module('csrf-refresh', {})
+
+asyncTest('refresh all csrf tokens', 1, function() {
+  var correctToken = 'cf50faa3fe97702ca1ae'
+
+  var form = $('<form />')
+  var input = $('<input>').attr({ type: 'hidden', name: 'authenticity_token', id: 'authenticity_token', value: 'foo' })
+  input.appendTo(form)
+
+  $('#qunit-fixture')
+    .append('<meta name="csrf-param" content="authenticity_token"/>')
+    .append('<meta name="csrf-token" content="' + correctToken + '"/>')
+    .append(form)
+
+  $.rails.refreshCSRFTokens()
+  currentToken = $('#qunit-fixture #authenticity_token').val()
+
+  start()
+  equal(currentToken, correctToken)
+})
+
+})()
diff --git a/actionview/test/ujs/public/test/csrf-token.js b/actionview/test/ujs/public/test/csrf-token.js
new file mode 100644
index 0000000000..388b40e057
--- /dev/null
+++ b/actionview/test/ujs/public/test/csrf-token.js
@@ -0,0 +1,27 @@
+(function() {
+
+module('csrf-token', {})
+
+asyncTest('find csrf token', 1, function() {
+  var correctToken = 'cf50faa3fe97702ca1ae'
+
+  $('#qunit-fixture').append('<meta name="csrf-token" content="' + correctToken + '"/>')
+
+  currentToken = $.rails.csrfToken()
+
+  start()
+  equal(currentToken, correctToken)
+})
+
+asyncTest('find csrf param', 1, function() {
+  var correctParam = 'authenticity_token'
+
+  $('#qunit-fixture').append('<meta name="csrf-param" content="' + correctParam + '"/>')
+
+  currentParam = $.rails.csrfParam()
+
+  start()
+  equal(currentParam, correctParam)
+})
+
+})()
diff --git a/actionview/test/ujs/public/test/data-confirm.js b/actionview/test/ujs/public/test/data-confirm.js
new file mode 100644
index 0000000000..d1ea82ea7e
--- /dev/null
+++ b/actionview/test/ujs/public/test/data-confirm.js
@@ -0,0 +1,316 @@
+module('data-confirm', {
+  setup: function() {
+    $('#qunit-fixture').append($('<a />', {
+      href: '/echo',
+      'data-remote': 'true',
+      'data-confirm': 'Are you absolutely sure?',
+      text: 'my social security number'
+    }))
+
+    $('#qunit-fixture').append($('<button />', {
+      'data-url': '/echo',
+      'data-remote': 'true',
+      'data-confirm': 'Are you absolutely sure?',
+      text: 'Click me'
+    }))
+
+    $('#qunit-fixture').append($('<form />', {
+      id: 'confirm',
+      action: '/echo',
+      'data-remote': 'true'
+    }))
+
+    $('#qunit-fixture').append($('<input />', {
+      type: 'submit',
+      form: 'confirm',
+      'data-confirm': 'Are you absolutely sure?'
+    }))
+
+    $('#qunit-fixture').append($('<button />', {
+      type: 'submit',
+      form: 'confirm',
+      disabled: 'disabled',
+      'data-confirm': 'Are you absolutely sure?'
+    }))
+
+    this.windowConfirm = window.confirm
+  },
+  teardown: function() {
+    window.confirm = this.windowConfirm
+  }
+})
+
+asyncTest('clicking on a link with data-confirm attribute. Confirm yes.', 6, function() {
+  var message
+  // auto-confirm:
+  window.confirm = function(msg) { message = msg; return true }
+
+  $('a[data-confirm]')
+    .bindNative('confirm:complete', function(e, data) {
+      App.assertCallbackInvoked('confirm:complete')
+      ok(data == true, 'confirm:complete passes in confirm answer (true)')
+    })
+    .bindNative('ajax:success', function(e, data, status, xhr) {
+      App.assertCallbackInvoked('ajax:success')
+      App.assertRequestPath(data, '/echo')
+      App.assertGetRequest(data)
+
+      equal(message, 'Are you absolutely sure?')
+      start()
+    })
+    .triggerNative('click')
+})
+
+asyncTest('clicking on a button with data-confirm attribute. Confirm yes.', 6, function() {
+  var message
+  // auto-confirm:
+  window.confirm = function(msg) { message = msg; return true }
+
+  $('button[data-confirm]')
+    .bindNative('confirm:complete', function(e, data) {
+      App.assertCallbackInvoked('confirm:complete')
+      ok(data == true, 'confirm:complete passes in confirm answer (true)')
+    })
+    .bindNative('ajax:success', function(e, data, status, xhr) {
+      App.assertCallbackInvoked('ajax:success')
+      App.assertRequestPath(data, '/echo')
+      App.assertGetRequest(data)
+
+      equal(message, 'Are you absolutely sure?')
+      start()
+    })
+    .triggerNative('click')
+})
+
+asyncTest('clicking on a link with data-confirm attribute. Confirm No.', 3, function() {
+  var message
+  // auto-decline:
+  window.confirm = function(msg) { message = msg; return false }
+
+  $('a[data-confirm]')
+    .bindNative('confirm:complete', function(e, data) {
+      App.assertCallbackInvoked('confirm:complete')
+      ok(data == false, 'confirm:complete passes in confirm answer (false)')
+    })
+    .bindNative('ajax:beforeSend', function(e, data, status, xhr) {
+      App.assertCallbackNotInvoked('ajax:beforeSend')
+    })
+    .triggerNative('click')
+
+  setTimeout(function() {
+    equal(message, 'Are you absolutely sure?')
+    start()
+  }, 50)
+})
+
+asyncTest('clicking on a button with data-confirm attribute. Confirm No.', 3, function() {
+  var message
+  // auto-decline:
+  window.confirm = function(msg) { message = msg; return false }
+
+  $('button[data-confirm]')
+    .bindNative('confirm:complete', function(e, data) {
+      App.assertCallbackInvoked('confirm:complete')
+      ok(data == false, 'confirm:complete passes in confirm answer (false)')
+    })
+    .bindNative('ajax:beforeSend', function(e, data, status, xhr) {
+      App.assertCallbackNotInvoked('ajax:beforeSend')
+    })
+    .triggerNative('click')
+
+  setTimeout(function() {
+    equal(message, 'Are you absolutely sure?')
+    start()
+  }, 50)
+})
+
+asyncTest('clicking on a button with data-confirm attribute. Confirm error.', 3, function() {
+  var message
+  // auto-decline:
+  window.confirm = function(msg) { message = msg; throw 'some random error' }
+
+  $('button[data-confirm]')
+    .bindNative('confirm:complete', function(e, data) {
+      App.assertCallbackInvoked('confirm:complete')
+      ok(data == false, 'confirm:complete passes in confirm answer (false)')
+    })
+    .bindNative('ajax:beforeSend', function(e, data, status, xhr) {
+      App.assertCallbackNotInvoked('ajax:beforeSend')
+    })
+    .triggerNative('click')
+
+  setTimeout(function() {
+    equal(message, 'Are you absolutely sure?')
+    start()
+  }, 50)
+})
+
+asyncTest('clicking on a submit button with form and data-confirm attributes. Confirm No.', 3, function() {
+  var message
+  // auto-decline:
+  window.confirm = function(msg) { message = msg; return false }
+
+  $('input[type=submit][form]')
+    .bindNative('confirm:complete', function(e, data) {
+      App.assertCallbackInvoked('confirm:complete')
+      ok(data == false, 'confirm:complete passes in confirm answer (false)')
+    })
+    .bindNative('ajax:beforeSend', function(e, data, status, xhr) {
+      App.assertCallbackNotInvoked('ajax:beforeSend')
+    })
+    .triggerNative('click')
+
+  setTimeout(function() {
+    equal(message, 'Are you absolutely sure?')
+    start()
+  }, 50)
+})
+
+asyncTest('binding to confirm event of a link and returning false', 1, function() {
+  // redefine confirm function so we can make sure it's not called
+  window.confirm = function(msg) {
+    ok(false, 'confirm dialog should not be called')
+  }
+
+  $('a[data-confirm]')
+    .bindNative('confirm', function() {
+      App.assertCallbackInvoked('confirm')
+      return false
+    })
+    .bindNative('confirm:complete', function() {
+      App.assertCallbackNotInvoked('confirm:complete')
+    })
+    .triggerNative('click')
+
+  setTimeout(function() {
+    start()
+  }, 50)
+})
+
+asyncTest('binding to confirm event of a button and returning false', 1, function() {
+  // redefine confirm function so we can make sure it's not called
+  window.confirm = function(msg) {
+    ok(false, 'confirm dialog should not be called')
+  }
+
+  $('button[data-confirm]')
+    .bindNative('confirm', function() {
+      App.assertCallbackInvoked('confirm')
+      return false
+    })
+    .bindNative('confirm:complete', function() {
+      App.assertCallbackNotInvoked('confirm:complete')
+    })
+    .triggerNative('click')
+
+  setTimeout(function() {
+    start()
+  }, 50)
+})
+
+asyncTest('binding to confirm:complete event of a link and returning false', 2, function() {
+  // auto-confirm:
+  window.confirm = function(msg) {
+    ok(true, 'confirm dialog should be called')
+    return true
+  }
+
+  $('a[data-confirm]')
+    .bindNative('confirm:complete', function() {
+      App.assertCallbackInvoked('confirm:complete')
+      return false
+    })
+    .bindNative('ajax:beforeSend', function() {
+      App.assertCallbackNotInvoked('ajax:beforeSend')
+    })
+    .triggerNative('click')
+
+  setTimeout(function() {
+    start()
+  }, 50)
+})
+
+asyncTest('binding to confirm:complete event of a button and returning false', 2, function() {
+  // auto-confirm:
+  window.confirm = function(msg) {
+    ok(true, 'confirm dialog should be called')
+    return true
+  }
+
+  $('button[data-confirm]')
+    .bindNative('confirm:complete', function() {
+      App.assertCallbackInvoked('confirm:complete')
+      return false
+    })
+    .bindNative('ajax:beforeSend', function() {
+      App.assertCallbackNotInvoked('ajax:beforeSend')
+    })
+    .triggerNative('click')
+
+  setTimeout(function() {
+    start()
+  }, 50)
+})
+
+asyncTest('a button inside a form only confirms once', 1, function() {
+  var confirmations = 0
+  window.confirm = function(msg) {
+    confirmations++
+    return true
+  }
+
+  $('#qunit-fixture').append($('<form />').append($('<button />', {
+    'data-remote': 'true',
+    'data-confirm': 'Are you absolutely sure?',
+    text: 'Click me'
+  })))
+
+  $('form > button[data-confirm]').triggerNative('click')
+
+  ok(confirmations === 1, 'confirmation counter should be 1, but it was ' + confirmations)
+  start()
+})
+
+asyncTest('clicking on the children of a link should also trigger a confirm', 6, function() {
+  var message
+  // auto-confirm:
+  window.confirm = function(msg) { message = msg; return true }
+
+  $('a[data-confirm]')
+    .html('<strong>Click me</strong>')
+    .bindNative('confirm:complete', function(e, data) {
+      App.assertCallbackInvoked('confirm:complete')
+      ok(data == true, 'confirm:complete passes in confirm answer (true)')
+    })
+    .bindNative('ajax:success', function(e, data, status, xhr) {
+      App.assertCallbackInvoked('ajax:success')
+      App.assertRequestPath(data, '/echo')
+      App.assertGetRequest(data)
+
+      equal(message, 'Are you absolutely sure?')
+      start()
+    })
+    .find('strong')
+    .triggerNative('click')
+})
+
+asyncTest('clicking on the children of a disabled button should not trigger a confirm.', 1, function() {
+  var message
+  // auto-decline:
+  window.confirm = function(msg) { message = msg; return false }
+
+  $('button[data-confirm][disabled]')
+    .html('<strong>Click me</strong>')
+    .bindNative('confirm', function() {
+      App.assertCallbackNotInvoked('confirm')
+    })
+    .find('strong')
+    .bindNative('click', function() {
+      App.assertCallbackInvoked('click')
+    })
+    .triggerNative('click')
+
+  setTimeout(function() {
+    start()
+  }, 50)
+})
diff --git a/actionview/test/ujs/public/test/data-disable-with.js b/actionview/test/ujs/public/test/data-disable-with.js
new file mode 100644
index 0000000000..b29cbbc867
--- /dev/null
+++ b/actionview/test/ujs/public/test/data-disable-with.js
@@ -0,0 +1,391 @@
+module('data-disable-with', {
+  setup: function() {
+    $('#qunit-fixture').append($('<form />', {
+      action: '/echo',
+      'data-remote': 'true',
+      method: 'post'
+    }))
+      .find('form')
+      .append($('<input type="text" data-disable-with="processing ..." name="user_name" value="john" />'))
+
+    $('#qunit-fixture').append($('<form />', {
+      action: '/echo',
+      method: 'post',
+      id: 'not_remote'
+    }))
+      .find('form:last')
+      // WEEIRDD: the form won't submit to an iframe if the button is name="submit" (??!)
+      .append($('<input type="submit" data-disable-with="submitting ..." name="submit2" value="Submit" />'))
+
+    $('#qunit-fixture').append($('<a />', {
+      text: 'Click me',
+      href: '/echo',
+      'data-disable-with': 'clicking...'
+    }))
+
+    $('#qunit-fixture').append($('<input />', {
+      type: 'submit',
+      form: 'not_remote',
+      'data-disable-with': 'form attr submitting',
+      name: 'submit3',
+      value: 'Form Attr Submit'
+    }))
+
+    $('#qunit-fixture').append($('<button />', {
+      text: 'Click me',
+      'data-remote': true,
+      'data-url': '/echo',
+      'data-disable-with': 'clicking...'
+    }))
+  },
+  teardown: function() {
+    $(document).unbind('iframe:loaded')
+  }
+})
+
+asyncTest('form input field with "data-disable-with" attribute', 7, function() {
+  var form = $('form[data-remote]'), input = form.find('input[type=text]')
+
+  App.checkEnabledState(input, 'john')
+
+  form.bindNative('ajax:success', function(e, data) {
+    setTimeout(function() {
+      App.checkEnabledState(input, 'john')
+      equal(data.params.user_name, 'john')
+      start()
+    }, 13)
+  })
+  form.triggerNative('submit')
+
+  App.checkDisabledState(input, 'processing ...')
+})
+
+asyncTest('blank form input field with "data-disable-with" attribute', 7, function() {
+  var form = $('form[data-remote]'), input = form.find('input[type=text]')
+
+  input.val('')
+  App.checkEnabledState(input, '')
+
+  form.bindNative('ajax:success', function(e, data) {
+    setTimeout(function() {
+      App.checkEnabledState(input, '')
+      equal(data.params.user_name, '')
+      start()
+    }, 13)
+  })
+  form.triggerNative('submit')
+
+  App.checkDisabledState(input, 'processing ...')
+})
+
+asyncTest('form button with "data-disable-with" attribute', 6, function() {
+  var form = $('form[data-remote]'), button = $('<button data-disable-with="submitting ..." name="submit2">Submit</button>')
+  form.append(button)
+
+  App.checkEnabledState(button, 'Submit')
+
+  form.bindNative('ajax:success', function(e, data) {
+    setTimeout(function() {
+      App.checkEnabledState(button, 'Submit')
+      start()
+    }, 13)
+  })
+  form.triggerNative('submit')
+
+  App.checkDisabledState(button, 'submitting ...')
+})
+
+asyncTest('form input[type=submit][data-disable-with] disables', 6, function() {
+  var form = $('form:not([data-remote])'), input = form.find('input[type=submit]')
+
+  App.checkEnabledState(input, 'Submit')
+
+  $(document).bind('iframe:loaded', function(e, data) {
+    setTimeout(function() {
+      App.checkDisabledState(input, 'submitting ...')
+      start()
+    }, 30)
+  })
+  form.triggerNative('submit')
+
+  setTimeout(function() {
+    App.checkDisabledState(input, 'submitting ...')
+  }, 30)
+})
+
+test('form input[type=submit][data-disable-with] re-enables when `pageshow` event is triggered', function() {
+  var form = $('form:not([data-remote])'), input = form.find('input[type=submit]')
+
+  App.checkEnabledState(input, 'Submit')
+
+  // Emulate the disabled state without submitting the form at all, what is the
+  // state after going back on firefox after submitting a form.
+  //
+  // See https://github.com/rails/jquery-ujs/issues/357
+  $.rails.disableElement(form[0])
+
+  App.checkDisabledState(input, 'submitting ...')
+
+  $(window).triggerNative('pageshow')
+
+  App.checkEnabledState(input, 'Submit')
+})
+
+asyncTest('form[data-remote] input[type=submit][data-disable-with] is replaced in ajax callback', 2, function() {
+  var form = $('form:not([data-remote])').attr('data-remote', 'true'), origFormContents = form.html()
+
+  form.bindNative('ajax:success', function() {
+    form.html(origFormContents)
+
+    setTimeout(function() {
+      var input = form.find('input[type=submit]')
+      App.checkEnabledState(input, 'Submit')
+      start()
+    }, 30)
+  }).triggerNative('submit')
+})
+
+asyncTest('form[data-remote] input[data-disable-with] is replaced with disabled field in ajax callback', 2, function() {
+  var form = $('form:not([data-remote])').attr('data-remote', 'true'), input = form.find('input[type=submit]'),
+      newDisabledInput = input.clone().attr('disabled', 'disabled')
+
+  form.bindNative('ajax:success', function() {
+    input.replaceWith(newDisabledInput)
+
+    setTimeout(function() {
+      App.checkEnabledState(newDisabledInput, 'Submit')
+      start()
+    }, 30)
+  }).triggerNative('submit')
+})
+
+asyncTest('form input[type=submit][data-disable-with] using "form" attribute disables', 6, function() {
+  var form = $('#not_remote'), input = $('input[form=not_remote]')
+  App.checkEnabledState(input, 'Form Attr Submit')
+
+  $(document).bind('iframe:loaded', function(e, data) {
+    setTimeout(function() {
+      App.checkDisabledState(input, 'form attr submitting')
+      start()
+    }, 30)
+  })
+  form.triggerNative('submit')
+
+  setTimeout(function() {
+    App.checkDisabledState(input, 'form attr submitting')
+  }, 30)
+
+})
+
+asyncTest('form[data-remote] textarea[data-disable-with] attribute', 3, function() {
+  var form = $('form[data-remote]'),
+      textarea = $('<textarea data-disable-with="processing ..." name="user_bio">born, lived, died.</textarea>').appendTo(form)
+
+  form.bindNative('ajax:success', function(e, data) {
+    setTimeout(function() {
+      equal(data.params.user_bio, 'born, lived, died.')
+      start()
+    }, 13)
+  })
+  form.triggerNative('submit')
+
+  App.checkDisabledState(textarea, 'processing ...')
+})
+
+asyncTest('a[data-disable-with] disables', 4, function() {
+  var link = $('a[data-disable-with]')
+
+  App.checkEnabledState(link, 'Click me')
+
+  link.triggerNative('click')
+  App.checkDisabledState(link, 'clicking...')
+  start()
+})
+
+test('a[data-disable-with] re-enables when `pageshow` event is triggered', function() {
+  var link = $('a[data-disable-with]')
+
+  App.checkEnabledState(link, 'Click me')
+
+  link.triggerNative('click')
+  App.checkDisabledState(link, 'clicking...')
+
+  $(window).triggerNative('pageshow')
+  App.checkEnabledState(link, 'Click me')
+})
+
+asyncTest('a[data-remote][data-disable-with] disables and re-enables', 6, function() {
+  var link = $('a[data-disable-with]').attr('data-remote', true)
+
+  App.checkEnabledState(link, 'Click me')
+
+  link
+    .bindNative('ajax:beforeSend', function() {
+      App.checkDisabledState(link, 'clicking...')
+    })
+    .bindNative('ajax:complete', function() {
+      setTimeout( function() {
+        App.checkEnabledState(link, 'Click me')
+        start()
+      }, 15)
+    })
+    .triggerNative('click')
+})
+
+asyncTest('a[data-remote][data-disable-with] re-enables when `ajax:before` event is cancelled', 6, function() {
+  var link = $('a[data-disable-with]').attr('data-remote', true)
+
+  App.checkEnabledState(link, 'Click me')
+
+  link
+    .bindNative('ajax:before', function() {
+      App.checkDisabledState(link, 'clicking...')
+      return false
+    })
+    .triggerNative('click')
+
+  setTimeout(function() {
+    App.checkEnabledState(link, 'Click me')
+    start()
+  }, 30)
+})
+
+asyncTest('a[data-remote][data-disable-with] re-enables when `ajax:beforeSend` event is cancelled', 6, function() {
+  var link = $('a[data-disable-with]').attr('data-remote', true)
+
+  App.checkEnabledState(link, 'Click me')
+
+  link
+    .bindNative('ajax:beforeSend', function() {
+      App.checkDisabledState(link, 'clicking...')
+      return false
+    })
+    .triggerNative('click')
+
+  setTimeout(function() {
+    App.checkEnabledState(link, 'Click me')
+    start()
+  }, 30)
+})
+
+asyncTest('a[data-remote][data-disable-with] re-enables when `ajax:error` event is triggered', 6, function() {
+  var link = $('a[data-disable-with]').attr('data-remote', true).attr('href', '/error')
+
+  App.checkEnabledState(link, 'Click me')
+
+  link
+    .bindNative('ajax:beforeSend', function() {
+      App.checkDisabledState(link, 'clicking...')
+    })
+    .triggerNative('click')
+
+  setTimeout(function() {
+    App.checkEnabledState(link, 'Click me')
+    start()
+  }, 30)
+})
+
+asyncTest('form[data-remote] input|button|textarea[data-disable-with] does not disable when `ajax:beforeSend` event is cancelled', 8, function() {
+  var form = $('form[data-remote]'),
+      input = form.find('input:text'),
+      button = $('<button data-disable-with="submitting ..." name="submit2">Submit</button>').appendTo(form),
+      textarea = $('<textarea data-disable-with="processing ..." name="user_bio">born, lived, died.</textarea>').appendTo(form),
+      submit = $('<input type="submit" data-disable-with="submitting ..." name="submit2" value="Submit" />').appendTo(form)
+
+  form
+    .bindNative('ajax:beforeSend', function() {
+      return false
+    })
+    .triggerNative('submit')
+
+  App.checkEnabledState(input, 'john')
+  App.checkEnabledState(button, 'Submit')
+  App.checkEnabledState(textarea, 'born, lived, died.')
+  App.checkEnabledState(submit, 'Submit')
+
+  start()
+})
+
+asyncTest('ctrl-clicking on a link does not disables the link', 6, function() {
+  var link = $('a[data-disable-with]')
+
+  App.checkEnabledState(link, 'Click me')
+
+  link.triggerNative('click', { metaKey: true })
+  App.checkEnabledState(link, 'Click me')
+
+  link.triggerNative('click', { metaKey: true })
+  App.checkEnabledState(link, 'Click me')
+  start()
+})
+
+asyncTest('button[data-remote][data-disable-with] disables and re-enables', 6, function() {
+  var button = $('button[data-remote][data-disable-with]')
+
+  App.checkEnabledState(button, 'Click me')
+
+  button
+    .bindNative('ajax:send', function() {
+      App.checkDisabledState(button, 'clicking...')
+    })
+    .bindNative('ajax:complete', function() {
+      setTimeout( function() {
+        App.checkEnabledState(button, 'Click me')
+        start()
+      }, 15)
+    })
+    .triggerNative('click')
+})
+
+asyncTest('button[data-remote][data-disable-with] re-enables when `ajax:before` event is cancelled', 6, function() {
+  var button = $('button[data-remote][data-disable-with]')
+
+  App.checkEnabledState(button, 'Click me')
+
+  button
+    .bindNative('ajax:before', function() {
+      App.checkDisabledState(button, 'clicking...')
+      return false
+    })
+    .triggerNative('click')
+
+  setTimeout(function() {
+    App.checkEnabledState(button, 'Click me')
+    start()
+  }, 30)
+})
+
+asyncTest('button[data-remote][data-disable-with] re-enables when `ajax:beforeSend` event is cancelled', 6, function() {
+  var button = $('button[data-remote][data-disable-with]')
+
+  App.checkEnabledState(button, 'Click me')
+
+  button
+    .bindNative('ajax:beforeSend', function() {
+      App.checkDisabledState(button, 'clicking...')
+      return false
+    })
+    .triggerNative('click')
+
+  setTimeout(function() {
+    App.checkEnabledState(button, 'Click me')
+    start()
+  }, 30)
+})
+
+asyncTest('button[data-remote][data-disable-with] re-enables when `ajax:error` event is triggered', 6, function() {
+  var button = $('a[data-disable-with]').attr('data-remote', true).attr('href', '/error')
+
+  App.checkEnabledState(button, 'Click me')
+
+  button
+    .bindNative('ajax:send', function() {
+      App.checkDisabledState(button, 'clicking...')
+    })
+    .triggerNative('click')
+
+  setTimeout(function() {
+    App.checkEnabledState(button, 'Click me')
+    start()
+  }, 30)
+})
diff --git a/actionview/test/ujs/public/test/data-disable.js b/actionview/test/ujs/public/test/data-disable.js
new file mode 100644
index 0000000000..ccc38cf9ae
--- /dev/null
+++ b/actionview/test/ujs/public/test/data-disable.js
@@ -0,0 +1,321 @@
+module('data-disable', {
+  setup: function() {
+    $('#qunit-fixture').append($('<form />', {
+      action: '/echo',
+      'data-remote': 'true',
+      method: 'post'
+    }))
+      .find('form')
+      .append($('<input type="text" data-disable name="user_name" value="john" />'))
+
+    $('#qunit-fixture').append($('<form />', {
+      action: '/echo',
+      method: 'post'
+    }))
+      .find('form:last')
+      // WEEIRDD: the form won't submit to an iframe if the button is name="submit" (??!)
+      .append($('<input type="submit" data-disable name="submit2" value="Submit" />'))
+
+    $('#qunit-fixture').append($('<a />', {
+      text: 'Click me',
+      href: '/echo',
+      'data-disable': 'true'
+    }))
+
+    $('#qunit-fixture').append($('<button />', {
+      text: 'Click me',
+      'data-remote': true,
+      'data-url': '/echo',
+      'data-disable': 'true'
+    }))
+  },
+  teardown: function() {
+    $(document).unbind('iframe:loaded')
+  }
+})
+
+asyncTest('form input field with "data-disable" attribute', 7, function() {
+  var form = $('form[data-remote]'), input = form.find('input[type=text]')
+
+  App.checkEnabledState(input, 'john')
+
+  form.bindNative('ajax:success', function(e, data) {
+    setTimeout(function() {
+      App.checkEnabledState(input, 'john')
+      equal(data.params.user_name, 'john')
+      start()
+    }, 13)
+  })
+  form.triggerNative('submit')
+
+  App.checkDisabledState(input, 'john')
+})
+
+asyncTest('form button with "data-disable" attribute', 7, function() {
+  var form = $('form[data-remote]'), button = $('<button data-disable name="submit2">Submit</button>')
+  form.append(button)
+
+  App.checkEnabledState(button, 'Submit')
+
+  form.bindNative('ajax:success', function(e, data) {
+    setTimeout(function() {
+      App.checkEnabledState(button, 'Submit')
+      start()
+    }, 13)
+  })
+  form.triggerNative('submit')
+
+  App.checkDisabledState(button, 'Submit')
+  equal(button.data('ujs:enable-with'), undefined)
+})
+
+asyncTest('form input[type=submit][data-disable] disables', 6, function() {
+  var form = $('form:not([data-remote])'), input = form.find('input[type=submit]')
+
+  App.checkEnabledState(input, 'Submit')
+
+  // WEEIRDD: attaching this handler makes the test work in IE7
+  $(document).bind('iframe:loading', function(e, f) {})
+
+  $(document).bind('iframe:loaded', function(e, data) {
+    setTimeout(function() {
+      App.checkDisabledState(input, 'Submit')
+      start()
+    }, 30)
+  })
+  form.triggerNative('submit')
+
+  setTimeout(function() {
+    App.checkDisabledState(input, 'Submit')
+  }, 30)
+})
+
+asyncTest('form[data-remote] input[type=submit][data-disable] is replaced in ajax callback', 2, function() {
+  var form = $('form:not([data-remote])').attr('data-remote', 'true'), origFormContents = form.html()
+
+  form.bindNative('ajax:success', function() {
+    form.html(origFormContents)
+
+    setTimeout(function() {
+      var input = form.find('input[type=submit]')
+      App.checkEnabledState(input, 'Submit')
+      start()
+    }, 30)
+  }).triggerNative('submit')
+})
+
+asyncTest('form[data-remote] input[data-disable] is replaced with disabled field in ajax callback', 2, function() {
+  var form = $('form:not([data-remote])').attr('data-remote', 'true'), input = form.find('input[type=submit]'),
+      newDisabledInput = input.clone().attr('disabled', 'disabled')
+
+  form.bindNative('ajax:success', function() {
+    input.replaceWith(newDisabledInput)
+
+    setTimeout(function() {
+      App.checkEnabledState(newDisabledInput, 'Submit')
+      start()
+    }, 30)
+  }).triggerNative('submit')
+})
+
+asyncTest('form[data-remote] textarea[data-disable] attribute', 3, function() {
+  var form = $('form[data-remote]'),
+      textarea = $('<textarea data-disable name="user_bio">born, lived, died.</textarea>').appendTo(form)
+
+  form.bindNative('ajax:success', function(e, data) {
+    setTimeout(function() {
+      equal(data.params.user_bio, 'born, lived, died.')
+      start()
+    }, 13)
+  })
+  form.triggerNative('submit')
+
+  App.checkDisabledState(textarea, 'born, lived, died.')
+})
+
+asyncTest('a[data-disable] disables', 5, function() {
+  var link = $('a[data-disable]')
+
+  App.checkEnabledState(link, 'Click me')
+
+  link.triggerNative('click')
+  App.checkDisabledState(link, 'Click me')
+  equal(link.data('ujs:enable-with'), undefined)
+  start()
+})
+
+asyncTest('a[data-remote][data-disable] disables and re-enables', 6, function() {
+  var link = $('a[data-disable]').attr('data-remote', true)
+
+  App.checkEnabledState(link, 'Click me')
+
+  link
+    .bindNative('ajax:send', function() {
+      App.checkDisabledState(link, 'Click me')
+    })
+    .bindNative('ajax:complete', function() {
+      setTimeout( function() {
+        App.checkEnabledState(link, 'Click me')
+        start()
+      }, 15)
+    })
+    .triggerNative('click')
+})
+
+asyncTest('a[data-remote][data-disable] re-enables when `ajax:before` event is cancelled', 6, function() {
+  var link = $('a[data-disable]').attr('data-remote', true)
+
+  App.checkEnabledState(link, 'Click me')
+
+  link
+    .bindNative('ajax:before', function() {
+      App.checkDisabledState(link, 'Click me')
+      return false
+    })
+    .triggerNative('click')
+
+  setTimeout(function() {
+    App.checkEnabledState(link, 'Click me')
+    start()
+  }, 30)
+})
+
+asyncTest('a[data-remote][data-disable] re-enables when `ajax:beforeSend` event is cancelled', 6, function() {
+  var link = $('a[data-disable]').attr('data-remote', true)
+
+  App.checkEnabledState(link, 'Click me')
+
+  link
+    .bindNative('ajax:beforeSend', function() {
+      App.checkDisabledState(link, 'Click me')
+      return false
+    })
+    .triggerNative('click')
+
+  setTimeout(function() {
+    App.checkEnabledState(link, 'Click me')
+    start()
+  }, 30)
+})
+
+asyncTest('a[data-remote][data-disable] re-enables when `ajax:error` event is triggered', 6, function() {
+  var link = $('a[data-disable]').attr('data-remote', true).attr('href', '/error')
+
+  App.checkEnabledState(link, 'Click me')
+
+  link
+    .bindNative('ajax:send', function() {
+      App.checkDisabledState(link, 'Click me')
+    })
+    .triggerNative('click')
+
+  setTimeout(function() {
+    App.checkEnabledState(link, 'Click me')
+    start()
+  }, 30)
+})
+
+asyncTest('form[data-remote] input|button|textarea[data-disable] does not disable when `ajax:beforeSend` event is cancelled', 8, function() {
+  var form = $('form[data-remote]'),
+      input = form.find('input:text'),
+      button = $('<button data-disable="submitting ..." name="submit2">Submit</button>').appendTo(form),
+      textarea = $('<textarea data-disable name="user_bio">born, lived, died.</textarea>').appendTo(form),
+      submit = $('<input type="submit" data-disable="submitting ..." name="submit2" value="Submit" />').appendTo(form)
+
+  form
+    .bindNative('ajax:beforeSend', function() {
+      return false
+    })
+    .triggerNative('submit')
+
+  App.checkEnabledState(input, 'john')
+  App.checkEnabledState(button, 'Submit')
+  App.checkEnabledState(textarea, 'born, lived, died.')
+  App.checkEnabledState(submit, 'Submit')
+
+  start()
+})
+
+asyncTest('ctrl-clicking on a link does not disables the link', 6, function() {
+  var link = $('a[data-disable]')
+
+  App.checkEnabledState(link, 'Click me')
+
+  link.triggerNative('click', { metaKey: true })
+  App.checkEnabledState(link, 'Click me')
+
+  link.triggerNative('click', { ctrlKey: true })
+  App.checkEnabledState(link, 'Click me')
+  start()
+})
+
+asyncTest('button[data-remote][data-disable] disables and re-enables', 6, function() {
+  var button = $('button[data-remote][data-disable]')
+
+  App.checkEnabledState(button, 'Click me')
+
+  button
+    .bindNative('ajax:send', function() {
+      App.checkDisabledState(button, 'Click me')
+    })
+    .bindNative('ajax:complete', function() {
+      setTimeout( function() {
+        App.checkEnabledState(button, 'Click me')
+        start()
+      }, 15)
+    })
+    .triggerNative('click')
+})
+
+asyncTest('button[data-remote][data-disable] re-enables when `ajax:before` event is cancelled', 6, function() {
+  var button = $('button[data-remote][data-disable]')
+
+  App.checkEnabledState(button, 'Click me')
+
+  button
+    .bindNative('ajax:before', function() {
+      App.checkDisabledState(button, 'Click me')
+      return false
+    })
+    .triggerNative('click')
+
+  setTimeout(function() {
+    App.checkEnabledState(button, 'Click me')
+    start()
+  }, 30)
+})
+
+asyncTest('button[data-remote][data-disable] re-enables when `ajax:beforeSend` event is cancelled', 6, function() {
+  var button = $('button[data-remote][data-disable]')
+
+  App.checkEnabledState(button, 'Click me')
+
+  button
+    .bindNative('ajax:beforeSend', function() {
+      App.checkDisabledState(button, 'Click me')
+      return false
+    })
+    .triggerNative('click')
+
+  setTimeout(function() {
+    App.checkEnabledState(button, 'Click me')
+    start()
+  }, 30)
+})
+
+asyncTest('button[data-remote][data-disable] re-enables when `ajax:error` event is triggered', 6, function() {
+  var button = $('a[data-disable]').attr('data-remote', true).attr('href', '/error')
+
+  App.checkEnabledState(button, 'Click me')
+
+  button
+    .bindNative('ajax:send', function() {
+      App.checkDisabledState(button, 'Click me')
+    })
+    .triggerNative('click')
+
+  setTimeout(function() {
+    App.checkEnabledState(button, 'Click me')
+    start()
+  }, 30)
+})
diff --git a/actionview/test/ujs/public/test/data-method.js b/actionview/test/ujs/public/test/data-method.js
new file mode 100644
index 0000000000..47d940c577
--- /dev/null
+++ b/actionview/test/ujs/public/test/data-method.js
@@ -0,0 +1,85 @@
+(function() {
+
+module('data-method', {
+  setup: function() {
+    $('#qunit-fixture').append($('<a />', {
+      href: '/echo', 'data-method': 'delete', text: 'destroy!'
+    }))
+  },
+  teardown: function() {
+    $(document).unbind('iframe:loaded')
+  }
+})
+
+function submit(fn, options) {
+  $(document).bind('iframe:loaded', function(e, data) {
+    fn(data)
+    start()
+  })
+
+  $('#qunit-fixture').find('a')
+    .triggerNative('click')
+}
+
+asyncTest('link with "data-method" set to "delete"', 3, function() {
+  submit(function(data) {
+    equal(data.REQUEST_METHOD, 'DELETE')
+    strictEqual(data.params.authenticity_token, undefined)
+    strictEqual(data.HTTP_X_CSRF_TOKEN, undefined)
+  })
+})
+
+asyncTest('click on the child of link with "data-method"', 3, function() {
+  $(document).bind('iframe:loaded', function(e, data) {
+    equal(data.REQUEST_METHOD, 'DELETE')
+    strictEqual(data.params.authenticity_token, undefined)
+    strictEqual(data.HTTP_X_CSRF_TOKEN, undefined)
+    start()
+  })
+  $('#qunit-fixture a').html('<strong>destroy!</strong>').find('strong').triggerNative('click')
+})
+
+asyncTest('link with "data-method" and CSRF', 1, function() {
+  $('#qunit-fixture')
+    .append('<meta name="csrf-param" content="authenticity_token"/>')
+    .append('<meta name="csrf-token" content="cf50faa3fe97702ca1ae"/>')
+
+  submit(function(data) {
+    equal(data.params.authenticity_token, 'cf50faa3fe97702ca1ae')
+  })
+})
+
+asyncTest('link "target" should be carried over to generated form', 1, function() {
+  $('a[data-method]').attr('target', 'super-special-frame')
+  submit(function(data) {
+    equal(data.params._target, 'super-special-frame')
+  })
+})
+
+asyncTest('link with "data-method" and cross origin', 1, function() {
+  var data = {}
+
+  $('#qunit-fixture')
+    .append('<meta name="csrf-param" content="authenticity_token"/>')
+    .append('<meta name="csrf-token" content="cf50faa3fe97702ca1ae"/>')
+
+  $(document).on('submit', 'form', function(e) {
+    $(e.currentTarget).serializeArray().map(function(item) {
+      data[item.name] = item.value
+    })
+
+    return false
+  })
+
+  var link = $('#qunit-fixture').find('a')
+
+  link.attr('href', 'http://www.alfajango.com')
+
+  link.triggerNative('click')
+
+  start()
+
+  notEqual(data.authenticity_token, 'cf50faa3fe97702ca1ae')
+})
+
+})()
diff --git a/actionview/test/ujs/public/test/data-remote.js b/actionview/test/ujs/public/test/data-remote.js
new file mode 100644
index 0000000000..cbbd4e6c92
--- /dev/null
+++ b/actionview/test/ujs/public/test/data-remote.js
@@ -0,0 +1,440 @@
+(function() {
+
+function buildSelect(attrs) {
+  attrs = $.extend({
+    'name': 'user_data', 'data-remote': 'true', 'data-url': '/echo', 'data-params': 'data1=value1'
+  }, attrs)
+
+  $('#qunit-fixture').append(
+    $('<select />', attrs)
+      .append($('<option />', {value: 'optionValue1', text: 'option1'}))
+      .append($('<option />', {value: 'optionValue2', text: 'option2'}))
+  )
+}
+
+module('data-remote', {
+  setup: function() {
+    $('#qunit-fixture')
+      .append($('<a />', {
+        href: '/echo',
+        'data-remote': 'true',
+        'data-params': 'data1=value1&data2=value2',
+        text: 'my address'
+      }))
+      .append($('<button />', {
+        'data-url': '/echo',
+        'data-remote': 'true',
+        'data-params': 'data1=value1&data2=value2',
+        text: 'my button'
+      }))
+      .append($('<form />', {
+        action: '/echo',
+        'data-remote': 'true',
+        method: 'post',
+        id: 'my-remote-form'
+      }))
+      .append($('<a />', {
+        href: '/echo',
+        'data-remote': 'true',
+        disabled: 'disabled',
+        text: 'Disabed link'
+      }))
+      .find('form').append($('<input type="text" name="user_name" value="john">'))
+
+  }
+})
+
+asyncTest('ctrl-clicking on a link does not fire ajaxyness', 0, function() {
+  var link = $('a[data-remote]')
+
+  // Ideally, we'd setup an iframe to intercept normal link clicks
+  // and add a test to make sure the iframe:loaded event is triggered.
+  // However, jquery doesn't actually cause a native `click` event and
+  // follow links using `trigger('click')`, it only fires bindings.
+  link
+    .removeAttr('data-params')
+    .bindNative('ajax:beforeSend', function() {
+      ok(false, 'ajax should not be triggered')
+    })
+
+  link.triggerNative('click', { metaKey: true })
+  link.triggerNative('click', { ctrlKey: true })
+
+  setTimeout(function() { start() }, 13)
+})
+
+asyncTest('ctrl-clicking on a link still fires ajax for non-GET links and for links with "data-params"', 2, function() {
+  var link = $('a[data-remote]')
+
+  link
+    .removeAttr('data-params')
+    .attr('data-method', 'POST')
+    .bindNative('ajax:beforeSend', function() {
+      ok(true, 'ajax should be triggered')
+    })
+    .triggerNative('click', { metaKey: true })
+
+  link
+    .removeAttr('data-method')
+    .attr('data-params', 'name=steve')
+    .triggerNative('click', { metaKey: true })
+
+  setTimeout(function() { start() }, 13)
+})
+
+asyncTest('clicking on a link with data-remote attribute', 5, function() {
+  $('a[data-remote]')
+    .bindNative('ajax:success', function(e, data, status, xhr) {
+      App.assertCallbackInvoked('ajax:success')
+      App.assertRequestPath(data, '/echo')
+      equal(data.params.data1, 'value1', 'ajax arguments should have key data1 with right value')
+      equal(data.params.data2, 'value2', 'ajax arguments should have key data2 with right value')
+      App.assertGetRequest(data)
+    })
+    .bindNative('ajax:complete', function() { start() })
+    .triggerNative('click')
+})
+
+asyncTest('clicking on a link with both query string in href and data-params', 4, function() {
+  $('a[data-remote]')
+    .attr('href', '/echo?data3=value3')
+    .bindNative('ajax:success', function(e, data, status, xhr) {
+      App.assertGetRequest(data)
+      equal(data.params.data1, 'value1', 'ajax arguments should have key data1 with right value')
+      equal(data.params.data2, 'value2', 'ajax arguments should have key data2 with right value')
+      equal(data.params.data3, 'value3', 'query string in url should be passed to server with right value')
+    })
+    .bindNative('ajax:complete', function() { start() })
+    .triggerNative('click')
+})
+
+asyncTest('clicking on a link with both query string in href and data-params with POST method', 4, function() {
+  $('a[data-remote]')
+    .attr('href', '/echo?data3=value3')
+    .attr('data-method', 'post')
+    .bindNative('ajax:success', function(e, data, status, xhr) {
+      App.assertPostRequest(data)
+      equal(data.params.data1, 'value1', 'ajax arguments should have key data1 with right value')
+      equal(data.params.data2, 'value2', 'ajax arguments should have key data2 with right value')
+      equal(data.params.data3, 'value3', 'query string in url should be passed to server with right value')
+    })
+    .bindNative('ajax:complete', function() { start() })
+    .triggerNative('click')
+})
+
+asyncTest('clicking on a link with disabled attribute', 0, function() {
+  $('a[disabled]')
+  .bindNative('ajax:before', function(e, data, status, xhr) {
+    App.assertCallbackNotInvoked('ajax:success')
+  })
+  .bindNative('ajax:complete', function() { start() })
+  .triggerNative('click')
+
+  setTimeout(function() {
+    start()
+  }, 13)
+})
+
+asyncTest('clicking on a button with data-remote attribute', 5, function() {
+  $('button[data-remote]')
+    .bindNative('ajax:success', function(e, data, status, xhr) {
+      App.assertCallbackInvoked('ajax:success')
+      App.assertRequestPath(data, '/echo')
+      equal(data.params.data1, 'value1', 'ajax arguments should have key data1 with right value')
+      equal(data.params.data2, 'value2', 'ajax arguments should have key data2 with right value')
+      App.assertGetRequest(data)
+    })
+    .bindNative('ajax:complete', function() { start() })
+    .triggerNative('click')
+})
+
+asyncTest('changing a select option with data-remote attribute', 5, function() {
+  buildSelect()
+
+  $('select[data-remote]')
+    .bindNative('ajax:success', function(e, data, status, xhr) {
+      App.assertCallbackInvoked('ajax:success')
+      App.assertRequestPath(data, '/echo')
+      equal(data.params.user_data, 'optionValue2', 'ajax arguments should have key term with right value')
+      equal(data.params.data1, 'value1', 'ajax arguments should have key data1 with right value')
+      App.assertGetRequest(data)
+    })
+    .bindNative('ajax:complete', function() { start() })
+    .val('optionValue2')
+    .triggerNative('change')
+})
+
+asyncTest('submitting form with data-remote attribute', 4, function() {
+  $('form[data-remote]')
+    .bindNative('ajax:success', function(e, data, status, xhr) {
+      App.assertCallbackInvoked('ajax:success')
+      App.assertRequestPath(data, '/echo')
+      equal(data.params.user_name, 'john', 'ajax arguments should have key user_name with right value')
+      App.assertPostRequest(data)
+    })
+    .bindNative('ajax:complete', function() { start() })
+    .triggerNative('submit')
+})
+
+asyncTest('submitting form with data-remote attribute should include inputs in a fieldset only once', 3, function() {
+  $('form[data-remote]')
+    .append('<fieldset><input name="items[]" value="Item" /></fieldset>')
+    .bindNative('ajax:success', function(e, data, status, xhr) {
+      App.assertCallbackInvoked('ajax:success')
+      equal(data.params.items.length, 1, 'ajax arguments should only have the item once')
+      App.assertPostRequest(data)
+    })
+    .bindNative('ajax:complete', function() {
+      $('form[data-remote], fieldset').remove()
+      start()
+    })
+    .triggerNative('submit')
+})
+
+asyncTest('submitting form with data-remote attribute submits input with matching [form] attribute', 6, function() {
+  $('#qunit-fixture')
+    .append($('<input type="text" name="user_data" value="value1" form="my-remote-form">'))
+    .append($('<input type="text" name="user_email" value="from@example.com" disabled="disabled" form="my-remote-form">'))
+
+  $('form[data-remote]')
+    .bindNative('ajax:success', function(e, data, status, xhr) {
+      App.assertCallbackInvoked('ajax:success')
+      App.assertRequestPath(data, '/echo')
+      equal(data.params.user_name, 'john', 'ajax arguments should have key user_name with right value')
+      equal(data.params.user_data, 'value1', 'ajax arguments should have key user_data with right value')
+      equal(data.params.user_email, undefined, 'ajax arguments should not have disabled field')
+      App.assertPostRequest(data)
+    })
+    .bindNative('ajax:complete', function() { start() })
+    .triggerNative('submit')
+})
+
+asyncTest('submitting form with data-remote attribute by clicking button with matching [form] attribute', 5, function() {
+  $('form[data-remote]')
+    .bindNative('ajax:success', function(e, data, status, xhr) {
+      App.assertCallbackInvoked('ajax:success')
+      App.assertRequestPath(data, '/echo')
+      equal(data.params.user_name, 'john', 'ajax arguments should have key user_name with right value')
+      equal(data.params.user_data, 'value2', 'ajax arguments should have key user_data with right value')
+      App.assertPostRequest(data)
+    })
+    .bindNative('ajax:complete', function() { start() })
+
+  $('<button />', {
+        type: 'submit',
+        name: 'user_data',
+        value: 'value1',
+        form: 'my-remote-form'
+      })
+    .appendTo($('#qunit-fixture'))
+
+  $('<button />', {
+      type: 'submit',
+      name: 'user_data',
+      value: 'value2',
+      form: 'my-remote-form'
+    })
+    .appendTo($('#qunit-fixture'))
+    .triggerNative('click')
+})
+
+asyncTest('form\'s submit bindings in browsers that don\'t support submit bubbling', 5, function() {
+  var form = $('form[data-remote]'), directBindingCalled = false
+
+  ok(!directBindingCalled, 'nothing is called')
+
+  form
+    .append($('<input type="submit" />'))
+    .bindNative('submit', function(event) {
+      ok(event.type == 'submit', 'submit event handlers are called with submit event')
+      ok(true, 'binding handler is called')
+      directBindingCalled = true
+    })
+    .bindNative('ajax:beforeSend', function() {
+      ok(true, 'form being submitted via ajax')
+      ok(directBindingCalled, 'binding handler already called')
+    })
+    .bindNative('ajax:complete', function() {
+      start()
+    })
+
+    if(!$.support.submitBubbles) {
+      // Must indrectly submit form via click to trigger jQuery's manual submit bubbling in IE
+      form.find('input[type=submit]')
+      .triggerNative('click')
+    } else {
+      form.triggerNative('submit')
+    }
+})
+
+asyncTest('returning false in form\'s submit bindings in non-submit-bubbling browsers', 1, function() {
+  var form = $('form[data-remote]')
+
+  form
+    .append($('<input type="submit" />'))
+    .bindNative('submit', function() {
+      ok(true, 'binding handler is called')
+      return false
+    })
+    .bindNative('ajax:beforeSend', function() {
+      ok(false, 'form should not be submitted')
+    })
+
+    if (!$.support.submitBubbles) {
+      // Must indrectly submit form via click to trigger jQuery's manual submit bubbling in IE
+      form.find('input[type=submit]').triggerNative('click')
+    } else {
+      form.triggerNative('submit')
+    }
+
+    setTimeout(function() { start() }, 13)
+})
+
+asyncTest('clicking on a link with falsy "data-remote" attribute does not fire ajaxyness', 0, function() {
+  $('a[data-remote]')
+    .attr('data-remote', 'false')
+    .bindNative('ajax:beforeSend', function() {
+      ok(false, 'ajax should not be triggered')
+    })
+    .bindNative('click', function() {
+      return false
+    })
+    .triggerNative('click')
+
+  setTimeout(function() { start() }, 20)
+})
+
+asyncTest('ctrl-clicking on a link with falsy "data-remote" attribute does not fire ajaxyness even if "data-params" present', 0, function() {
+  var link = $('a[data-remote]')
+
+  link
+    .removeAttr('data-params')
+    .attr('data-remote', 'false')
+    .attr('data-method', 'POST')
+    .bindNative('ajax:beforeSend', function() {
+      ok(false, 'ajax should not be triggered')
+    })
+    .bindNative('click', function() {
+      return false
+    })
+    .triggerNative('click', { metaKey: true })
+
+  link
+    .removeAttr('data-method')
+    .attr('data-params', 'name=steve')
+    .triggerNative('click', { metaKey: true })
+
+  setTimeout(function() { start() }, 20)
+})
+
+asyncTest('clicking on a button with falsy "data-remote" attribute', 0, function() {
+  $('button[data-remote]:first')
+    .attr('data-remote', 'false')
+    .bindNative('ajax:beforeSend', function() {
+      ok(false, 'ajax should not be triggered')
+    })
+    .bindNative('click', function() {
+      return false
+    })
+    .triggerNative('click')
+
+  setTimeout(function() { start() }, 20)
+})
+
+asyncTest('submitting a form with falsy "data-remote" attribute', 0, function() {
+  $('form[data-remote]:first')
+    .attr('data-remote', 'false')
+    .bindNative('ajax:beforeSend', function() {
+      ok(false, 'ajax should not be triggered')
+    })
+    .bindNative('submit', function() {
+      return false
+    })
+    .triggerNative('submit')
+
+  setTimeout(function() { start() }, 20)
+})
+
+asyncTest('changing a select option with falsy "data-remote" attribute', 0, function() {
+  buildSelect({'data-remote': 'false'})
+
+  $('select[data-remote=false]:first')
+    .bindNative('ajax:beforeSend', function() {
+      ok(false, 'ajax should not be triggered')
+    })
+    .val('optionValue2')
+    .triggerNative('change')
+
+  setTimeout(function() { start() }, 20)
+})
+
+asyncTest('form should be serialized correctly', 6, function() {
+  $('form')
+    .append('<textarea name="textarea">textarea</textarea>')
+    .append('<input type="checkbox" name="checkbox[]" value="0" />')
+    .append('<input type="checkbox" checked="checked" name="checkbox[]" value="1" />')
+    .append('<input type="radio" checked="checked" name="radio" value="0" />')
+    .append('<input type="radio" name="radio" value="1" />')
+    .append('<select multiple="multiple" name="select[]">\
+      <option value="1" selected>1</option>\
+      <option value="2" selected>2</option>\
+      <option value="3">3</option>\
+      <option selected>4</option>\
+    </select>')
+    .bindNative('ajax:success', function(e, data, status, xhr) {
+      equal(data.params.checkbox.length, 1)
+      equal(data.params.checkbox[0], '1')
+      equal(data.params.radio, '0')
+      equal(data.params.select.length, 3)
+      equal(data.params.select[2], '4')
+      equal(data.params.textarea, 'textarea')
+
+      start()
+    })
+    .triggerNative('submit')
+})
+
+asyncTest('form buttons should only be serialized when clicked', 4, function() {
+  $('form')
+    .append('<input type="submit" name="submit1" value="submit1" />')
+    .append('<button name="submit2" value="submit2" />')
+    .append('<button name="submit3" value="submit3" />')
+    .bindNative('ajax:success', function(e, data, status, xhr) {
+      equal(data.params.submit1, undefined)
+      equal(data.params.submit2, 'submit2')
+      equal(data.params.submit3, undefined)
+      equal(data['rack.request.form_vars'], 'user_name=john&submit2=submit2')
+
+      start()
+    })
+    .find('[name=submit2]').triggerNative('click')
+})
+
+asyncTest('changing a select option without "data-url" attribute still fires ajax request to current location', 1, function() {
+  var currentLocation, ajaxLocation
+
+  buildSelect({'data-url': ''})
+
+  $('select[data-remote]')
+    .bindNative('ajax:beforeSend', function(e, xhr, settings) {
+      // Get current location (the same way jQuery does)
+      try {
+        currentLocation = location.href
+      } catch(err) {
+        currentLocation = document.createElement( 'a' )
+        currentLocation.href = ''
+        currentLocation = currentLocation.href
+      }
+
+      ajaxLocation = settings.url.replace(settings.data, '').replace(/&$/, '').replace(/\?$/, '')
+      equal(ajaxLocation, currentLocation, 'URL should be current page by default')
+
+      return false
+    })
+    .val('optionValue2')
+    .triggerNative('change')
+
+  setTimeout(function() { start() }, 20)
+})
+
+})()
diff --git a/actionview/test/ujs/public/test/override.js b/actionview/test/ujs/public/test/override.js
new file mode 100644
index 0000000000..299c7018cc
--- /dev/null
+++ b/actionview/test/ujs/public/test/override.js
@@ -0,0 +1,56 @@
+(function() {
+
+var realHref
+
+module('override', {
+  setup: function() {
+    realHref = $.rails.href
+    $('#qunit-fixture')
+      .append($('<a />', {
+        href: '/real/href', 'data-remote': 'true', 'data-method': 'delete', 'data-href': '/data/href'
+      }))
+  },
+  teardown: function() {
+    $.rails.href = realHref
+  }
+})
+
+asyncTest('the getter for an element\'s href is publicly accessible', 1, function() {
+  ok($.rails.href)
+  start()
+})
+
+asyncTest('the getter for an element\'s href is overridable', 1, function() {
+  $.rails.href = function(element) { return $(element).data('href') }
+  $('#qunit-fixture a')
+    .bindNative('ajax:beforeSend', function(e, xhr, options) {
+      equal('/data/href', options.url)
+      return false
+    })
+    .triggerNative('click')
+  start()
+})
+
+asyncTest('the getter for an element\'s href works normally if not overridden', 1, function() {
+  $('#qunit-fixture a')
+    .bindNative('ajax:beforeSend', function(e, xhr, options) {
+      equal(location.protocol + '//' + location.host + '/real/href', options.url)
+      return false
+    })
+    .triggerNative('click')
+  start()
+})
+
+asyncTest('the event selector strings are overridable', 1, function() {
+  ok($.rails.linkClickSelector.indexOf(', a[data-custom-remote-link]') != -1, 'linkClickSelector contains custom selector')
+  start()
+})
+
+asyncTest('including rails-ujs multiple times throws error', 1, function() {
+  throws(function() {
+    Rails.start()
+  }, 'appending rails.js again throws error')
+  setTimeout(function() { start() }, 50)
+})
+
+})()
diff --git a/actionview/test/ujs/public/test/settings.js b/actionview/test/ujs/public/test/settings.js
new file mode 100644
index 0000000000..299c71bb00
--- /dev/null
+++ b/actionview/test/ujs/public/test/settings.js
@@ -0,0 +1,116 @@
+var App = App || {}
+
+App.assertCallbackInvoked = function(callbackName) {
+  ok(true, callbackName + ' callback should have been invoked')
+}
+
+App.assertCallbackNotInvoked = function(callbackName) {
+  ok(false, callbackName + ' callback should not have been invoked')
+}
+
+App.assertGetRequest = function(requestEnv) {
+  equal(requestEnv['REQUEST_METHOD'], 'GET', 'request type should be GET')
+}
+
+App.assertPostRequest = function(requestEnv) {
+  equal(requestEnv['REQUEST_METHOD'], 'POST', 'request type should be POST')
+}
+
+App.assertRequestPath = function(requestEnv, path) {
+  equal(requestEnv['PATH_INFO'], path, 'request should be sent to right url')
+}
+
+App.getVal = function(el) {
+  return el.is('input,textarea,select') ? el.val() : el.text()
+}
+
+App.disabled = function(el) {
+  return el.is('input,textarea,select,button') ?
+    (el.is(':disabled') && $.rails.getData(el[0], 'ujs:disabled')) :
+    $.rails.getData(el[0], 'ujs:disabled')
+}
+
+App.checkEnabledState = function(el, text) {
+  ok(!App.disabled(el), el.get(0).tagName + ' should not be disabled')
+  equal(App.getVal(el), text, el.get(0).tagName + ' text should be original value')
+}
+
+App.checkDisabledState = function(el, text) {
+  ok(App.disabled(el), el.get(0).tagName + ' should be disabled')
+  equal(App.getVal(el), text, el.get(0).tagName + ' text should be disabled value')
+}
+
+// hijacks normal form submit; lets it submit to an iframe to prevent
+// navigating away from the test suite
+$(document).bind('submit', function(e) {
+  if (!e.isDefaultPrevented()) {
+    var form = $(e.target), action = form.attr('action'),
+        name = 'form-frame' + jQuery.guid++,
+        iframe = $('<iframe name="' + name + '" />'),
+        iframeInput = '<input name="iframe" value="true" type="hidden" />'
+        targetInput = '<input name="_target" value="' + (form.attr('target') || '') + '" type="hidden" />'
+
+    if (action && action.indexOf('iframe') < 0) {
+      if (action.indexOf('?') < 0) {
+        form.attr('action', action + '?iframe=true')
+      } else {
+        form.attr('action', action + '&iframe=true')
+      }
+    }
+    form.attr('target', name).append(iframeInput, targetInput)
+    $('#qunit-fixture').append(iframe)
+    $.event.trigger('iframe:loading', form)
+  }
+})
+
+var _MouseEvent = window.MouseEvent
+
+try {
+  new _MouseEvent()
+} catch (e) {
+  _MouseEvent = function(type, options) {
+    var evt = document.createEvent('MouseEvents')
+    evt.initMouseEvent(type, options.bubbles, options.cancelable, window, options.detail, 0, 0, 80, 20, options.ctrlKey, options.altKey, options.shiftKey, options.metaKey, 0, null)
+    return evt
+  }
+}
+
+$.fn.extend({
+  // trigger a native click event
+  triggerNative: function(type, options) {
+    var el = this[0],
+        event,
+        Evt = {
+          'click': _MouseEvent,
+          'change': Event,
+          'pageshow': PageTransitionEvent,
+          'submit': Event
+        }[type]
+
+    options = options || {}
+    options.bubbles = true
+    options.cancelable = true
+
+    event = new Evt(type, options)
+
+    el.dispatchEvent(event)
+
+    if (type === 'submit' && !event.defaultPrevented) {
+      el.submit()
+    }
+    return this
+  },
+  bindNative: function(event, handler) {
+    if (!handler) return this
+
+    this.bind(event, function(e) {
+      var args = []
+      if (e.originalEvent.detail) {
+        args = e.originalEvent.detail.slice()
+      }
+      args.unshift(e)
+      return handler.apply(this, args)
+    })
+    return this
+  }
+})
diff --git a/actionview/test/ujs/public/vendor/jquery-2.2.0.js b/actionview/test/ujs/public/vendor/jquery-2.2.0.js
new file mode 100644
index 0000000000..1e0ba99740
--- /dev/null
+++ b/actionview/test/ujs/public/vendor/jquery-2.2.0.js
@@ -0,0 +1,9831 @@
+/*!
+ * jQuery JavaScript Library v2.2.0
+ * http://jquery.com/
+ *
+ * Includes Sizzle.js
+ * http://sizzlejs.com/
+ *
+ * Copyright jQuery Foundation and other contributors
+ * Released under the MIT license
+ * http://jquery.org/license
+ *
+ * Date: 2016-01-08T20:02Z
+ */
+
+(function( global, factory ) {
+
+	if ( typeof module === "object" && typeof module.exports === "object" ) {
+		// For CommonJS and CommonJS-like environments where a proper `window`
+		// is present, execute the factory and get jQuery.
+		// For environments that do not have a `window` with a `document`
+		// (such as Node.js), expose a factory as module.exports.
+		// This accentuates the need for the creation of a real `window`.
+		// e.g. var jQuery = require("jquery")(window);
+		// See ticket #14549 for more info.
+		module.exports = global.document ?
+			factory( global, true ) :
+			function( w ) {
+				if ( !w.document ) {
+					throw new Error( "jQuery requires a window with a document" );
+				}
+				return factory( w );
+			};
+	} else {
+		factory( global );
+	}
+
+// Pass this if window is not defined yet
+}(typeof window !== "undefined" ? window : this, function( window, noGlobal ) {
+
+// Support: Firefox 18+
+// Can't be in strict mode, several libs including ASP.NET trace
+// the stack via arguments.caller.callee and Firefox dies if
+// you try to trace through "use strict" call chains. (#13335)
+//"use strict";
+var arr = [];
+
+var document = window.document;
+
+var slice = arr.slice;
+
+var concat = arr.concat;
+
+var push = arr.push;
+
+var indexOf = arr.indexOf;
+
+var class2type = {};
+
+var toString = class2type.toString;
+
+var hasOwn = class2type.hasOwnProperty;
+
+var support = {};
+
+
+
+var
+	version = "2.2.0",
+
+	// Define a local copy of jQuery
+	jQuery = function( selector, context ) {
+
+		// The jQuery object is actually just the init constructor 'enhanced'
+		// Need init if jQuery is called (just allow error to be thrown if not included)
+		return new jQuery.fn.init( selector, context );
+	},
+
+	// Support: Android<4.1
+	// Make sure we trim BOM and NBSP
+	rtrim = /^[\s\uFEFF\xA0]+|[\s\uFEFF\xA0]+$/g,
+
+	// Matches dashed string for camelizing
+	rmsPrefix = /^-ms-/,
+	rdashAlpha = /-([\da-z])/gi,
+
+	// Used by jQuery.camelCase as callback to replace()
+	fcamelCase = function( all, letter ) {
+		return letter.toUpperCase();
+	};
+
+jQuery.fn = jQuery.prototype = {
+
+	// The current version of jQuery being used
+	jquery: version,
+
+	constructor: jQuery,
+
+	// Start with an empty selector
+	selector: "",
+
+	// The default length of a jQuery object is 0
+	length: 0,
+
+	toArray: function() {
+		return slice.call( this );
+	},
+
+	// Get the Nth element in the matched element set OR
+	// Get the whole matched element set as a clean array
+	get: function( num ) {
+		return num != null ?
+
+			// Return just the one element from the set
+			( num < 0 ? this[ num + this.length ] : this[ num ] ) :
+
+			// Return all the elements in a clean array
+			slice.call( this );
+	},
+
+	// Take an array of elements and push it onto the stack
+	// (returning the new matched element set)
+	pushStack: function( elems ) {
+
+		// Build a new jQuery matched element set
+		var ret = jQuery.merge( this.constructor(), elems );
+
+		// Add the old object onto the stack (as a reference)
+		ret.prevObject = this;
+		ret.context = this.context;
+
+		// Return the newly-formed element set
+		return ret;
+	},
+
+	// Execute a callback for every element in the matched set.
+	each: function( callback ) {
+		return jQuery.each( this, callback );
+	},
+
+	map: function( callback ) {
+		return this.pushStack( jQuery.map( this, function( elem, i ) {
+			return callback.call( elem, i, elem );
+		} ) );
+	},
+
+	slice: function() {
+		return this.pushStack( slice.apply( this, arguments ) );
+	},
+
+	first: function() {
+		return this.eq( 0 );
+	},
+
+	last: function() {
+		return this.eq( -1 );
+	},
+
+	eq: function( i ) {
+		var len = this.length,
+			j = +i + ( i < 0 ? len : 0 );
+		return this.pushStack( j >= 0 && j < len ? [ this[ j ] ] : [] );
+	},
+
+	end: function() {
+		return this.prevObject || this.constructor();
+	},
+
+	// For internal use only.
+	// Behaves like an Array's method, not like a jQuery method.
+	push: push,
+	sort: arr.sort,
+	splice: arr.splice
+};
+
+jQuery.extend = jQuery.fn.extend = function() {
+	var options, name, src, copy, copyIsArray, clone,
+		target = arguments[ 0 ] || {},
+		i = 1,
+		length = arguments.length,
+		deep = false;
+
+	// Handle a deep copy situation
+	if ( typeof target === "boolean" ) {
+		deep = target;
+
+		// Skip the boolean and the target
+		target = arguments[ i ] || {};
+		i++;
+	}
+
+	// Handle case when target is a string or something (possible in deep copy)
+	if ( typeof target !== "object" && !jQuery.isFunction( target ) ) {
+		target = {};
+	}
+
+	// Extend jQuery itself if only one argument is passed
+	if ( i === length ) {
+		target = this;
+		i--;
+	}
+
+	for ( ; i < length; i++ ) {
+
+		// Only deal with non-null/undefined values
+		if ( ( options = arguments[ i ] ) != null ) {
+
+			// Extend the base object
+			for ( name in options ) {
+				src = target[ name ];
+				copy = options[ name ];
+
+				// Prevent never-ending loop
+				if ( target === copy ) {
+					continue;
+				}
+
+				// Recurse if we're merging plain objects or arrays
+				if ( deep && copy && ( jQuery.isPlainObject( copy ) ||
+					( copyIsArray = jQuery.isArray( copy ) ) ) ) {
+
+					if ( copyIsArray ) {
+						copyIsArray = false;
+						clone = src && jQuery.isArray( src ) ? src : [];
+
+					} else {
+						clone = src && jQuery.isPlainObject( src ) ? src : {};
+					}
+
+					// Never move original objects, clone them
+					target[ name ] = jQuery.extend( deep, clone, copy );
+
+				// Don't bring in undefined values
+				} else if ( copy !== undefined ) {
+					target[ name ] = copy;
+				}
+			}
+		}
+	}
+
+	// Return the modified object
+	return target;
+};
+
+jQuery.extend( {
+
+	// Unique for each copy of jQuery on the page
+	expando: "jQuery" + ( version + Math.random() ).replace( /\D/g, "" ),
+
+	// Assume jQuery is ready without the ready module
+	isReady: true,
+
+	error: function( msg ) {
+		throw new Error( msg );
+	},
+
+	noop: function() {},
+
+	isFunction: function( obj ) {
+		return jQuery.type( obj ) === "function";
+	},
+
+	isArray: Array.isArray,
+
+	isWindow: function( obj ) {
+		return obj != null && obj === obj.window;
+	},
+
+	isNumeric: function( obj ) {
+
+		// parseFloat NaNs numeric-cast false positives (null|true|false|"")
+		// ...but misinterprets leading-number strings, particularly hex literals ("0x...")
+		// subtraction forces infinities to NaN
+		// adding 1 corrects loss of precision from parseFloat (#15100)
+		var realStringObj = obj && obj.toString();
+		return !jQuery.isArray( obj ) && ( realStringObj - parseFloat( realStringObj ) + 1 ) >= 0;
+	},
+
+	isPlainObject: function( obj ) {
+
+		// Not plain objects:
+		// - Any object or value whose internal [[Class]] property is not "[object Object]"
+		// - DOM nodes
+		// - window
+		if ( jQuery.type( obj ) !== "object" || obj.nodeType || jQuery.isWindow( obj ) ) {
+			return false;
+		}
+
+		if ( obj.constructor &&
+				!hasOwn.call( obj.constructor.prototype, "isPrototypeOf" ) ) {
+			return false;
+		}
+
+		// If the function hasn't returned already, we're confident that
+		// |obj| is a plain object, created by {} or constructed with new Object
+		return true;
+	},
+
+	isEmptyObject: function( obj ) {
+		var name;
+		for ( name in obj ) {
+			return false;
+		}
+		return true;
+	},
+
+	type: function( obj ) {
+		if ( obj == null ) {
+			return obj + "";
+		}
+
+		// Support: Android<4.0, iOS<6 (functionish RegExp)
+		return typeof obj === "object" || typeof obj === "function" ?
+			class2type[ toString.call( obj ) ] || "object" :
+			typeof obj;
+	},
+
+	// Evaluates a script in a global context
+	globalEval: function( code ) {
+		var script,
+			indirect = eval;
+
+		code = jQuery.trim( code );
+
+		if ( code ) {
+
+			// If the code includes a valid, prologue position
+			// strict mode pragma, execute code by injecting a
+			// script tag into the document.
+			if ( code.indexOf( "use strict" ) === 1 ) {
+				script = document.createElement( "script" );
+				script.text = code;
+				document.head.appendChild( script ).parentNode.removeChild( script );
+			} else {
+
+				// Otherwise, avoid the DOM node creation, insertion
+				// and removal by using an indirect global eval
+
+				indirect( code );
+			}
+		}
+	},
+
+	// Convert dashed to camelCase; used by the css and data modules
+	// Support: IE9-11+
+	// Microsoft forgot to hump their vendor prefix (#9572)
+	camelCase: function( string ) {
+		return string.replace( rmsPrefix, "ms-" ).replace( rdashAlpha, fcamelCase );
+	},
+
+	nodeName: function( elem, name ) {
+		return elem.nodeName && elem.nodeName.toLowerCase() === name.toLowerCase();
+	},
+
+	each: function( obj, callback ) {
+		var length, i = 0;
+
+		if ( isArrayLike( obj ) ) {
+			length = obj.length;
+			for ( ; i < length; i++ ) {
+				if ( callback.call( obj[ i ], i, obj[ i ] ) === false ) {
+					break;
+				}
+			}
+		} else {
+			for ( i in obj ) {
+				if ( callback.call( obj[ i ], i, obj[ i ] ) === false ) {
+					break;
+				}
+			}
+		}
+
+		return obj;
+	},
+
+	// Support: Android<4.1
+	trim: function( text ) {
+		return text == null ?
+			"" :
+			( text + "" ).replace( rtrim, "" );
+	},
+
+	// results is for internal usage only
+	makeArray: function( arr, results ) {
+		var ret = results || [];
+
+		if ( arr != null ) {
+			if ( isArrayLike( Object( arr ) ) ) {
+				jQuery.merge( ret,
+					typeof arr === "string" ?
+					[ arr ] : arr
+				);
+			} else {
+				push.call( ret, arr );
+			}
+		}
+
+		return ret;
+	},
+
+	inArray: function( elem, arr, i ) {
+		return arr == null ? -1 : indexOf.call( arr, elem, i );
+	},
+
+	merge: function( first, second ) {
+		var len = +second.length,
+			j = 0,
+			i = first.length;
+
+		for ( ; j < len; j++ ) {
+			first[ i++ ] = second[ j ];
+		}
+
+		first.length = i;
+
+		return first;
+	},
+
+	grep: function( elems, callback, invert ) {
+		var callbackInverse,
+			matches = [],
+			i = 0,
+			length = elems.length,
+			callbackExpect = !invert;
+
+		// Go through the array, only saving the items
+		// that pass the validator function
+		for ( ; i < length; i++ ) {
+			callbackInverse = !callback( elems[ i ], i );
+			if ( callbackInverse !== callbackExpect ) {
+				matches.push( elems[ i ] );
+			}
+		}
+
+		return matches;
+	},
+
+	// arg is for internal usage only
+	map: function( elems, callback, arg ) {
+		var length, value,
+			i = 0,
+			ret = [];
+
+		// Go through the array, translating each of the items to their new values
+		if ( isArrayLike( elems ) ) {
+			length = elems.length;
+			for ( ; i < length; i++ ) {
+				value = callback( elems[ i ], i, arg );
+
+				if ( value != null ) {
+					ret.push( value );
+				}
+			}
+
+		// Go through every key on the object,
+		} else {
+			for ( i in elems ) {
+				value = callback( elems[ i ], i, arg );
+
+				if ( value != null ) {
+					ret.push( value );
+				}
+			}
+		}
+
+		// Flatten any nested arrays
+		return concat.apply( [], ret );
+	},
+
+	// A global GUID counter for objects
+	guid: 1,
+
+	// Bind a function to a context, optionally partially applying any
+	// arguments.
+	proxy: function( fn, context ) {
+		var tmp, args, proxy;
+
+		if ( typeof context === "string" ) {
+			tmp = fn[ context ];
+			context = fn;
+			fn = tmp;
+		}
+
+		// Quick check to determine if target is callable, in the spec
+		// this throws a TypeError, but we will just return undefined.
+		if ( !jQuery.isFunction( fn ) ) {
+			return undefined;
+		}
+
+		// Simulated bind
+		args = slice.call( arguments, 2 );
+		proxy = function() {
+			return fn.apply( context || this, args.concat( slice.call( arguments ) ) );
+		};
+
+		// Set the guid of unique handler to the same of original handler, so it can be removed
+		proxy.guid = fn.guid = fn.guid || jQuery.guid++;
+
+		return proxy;
+	},
+
+	now: Date.now,
+
+	// jQuery.support is not used in Core but other projects attach their
+	// properties to it so it needs to exist.
+	support: support
+} );
+
+// JSHint would error on this code due to the Symbol not being defined in ES5.
+// Defining this global in .jshintrc would create a danger of using the global
+// unguarded in another place, it seems safer to just disable JSHint for these
+// three lines.
+/* jshint ignore: start */
+if ( typeof Symbol === "function" ) {
+	jQuery.fn[ Symbol.iterator ] = arr[ Symbol.iterator ];
+}
+/* jshint ignore: end */
+
+// Populate the class2type map
+jQuery.each( "Boolean Number String Function Array Date RegExp Object Error Symbol".split( " " ),
+function( i, name ) {
+	class2type[ "[object " + name + "]" ] = name.toLowerCase();
+} );
+
+function isArrayLike( obj ) {
+
+	// Support: iOS 8.2 (not reproducible in simulator)
+	// `in` check used to prevent JIT error (gh-2145)
+	// hasOwn isn't used here due to false negatives
+	// regarding Nodelist length in IE
+	var length = !!obj && "length" in obj && obj.length,
+		type = jQuery.type( obj );
+
+	if ( type === "function" || jQuery.isWindow( obj ) ) {
+		return false;
+	}
+
+	return type === "array" || length === 0 ||
+		typeof length === "number" && length > 0 && ( length - 1 ) in obj;
+}
+var Sizzle =
+/*!
+ * Sizzle CSS Selector Engine v2.2.1
+ * http://sizzlejs.com/
+ *
+ * Copyright jQuery Foundation and other contributors
+ * Released under the MIT license
+ * http://jquery.org/license
+ *
+ * Date: 2015-10-17
+ */
+(function( window ) {
+
+var i,
+	support,
+	Expr,
+	getText,
+	isXML,
+	tokenize,
+	compile,
+	select,
+	outermostContext,
+	sortInput,
+	hasDuplicate,
+
+	// Local document vars
+	setDocument,
+	document,
+	docElem,
+	documentIsHTML,
+	rbuggyQSA,
+	rbuggyMatches,
+	matches,
+	contains,
+
+	// Instance-specific data
+	expando = "sizzle" + 1 * new Date(),
+	preferredDoc = window.document,
+	dirruns = 0,
+	done = 0,
+	classCache = createCache(),
+	tokenCache = createCache(),
+	compilerCache = createCache(),
+	sortOrder = function( a, b ) {
+		if ( a === b ) {
+			hasDuplicate = true;
+		}
+		return 0;
+	},
+
+	// General-purpose constants
+	MAX_NEGATIVE = 1 << 31,
+
+	// Instance methods
+	hasOwn = ({}).hasOwnProperty,
+	arr = [],
+	pop = arr.pop,
+	push_native = arr.push,
+	push = arr.push,
+	slice = arr.slice,
+	// Use a stripped-down indexOf as it's faster than native
+	// http://jsperf.com/thor-indexof-vs-for/5
+	indexOf = function( list, elem ) {
+		var i = 0,
+			len = list.length;
+		for ( ; i < len; i++ ) {
+			if ( list[i] === elem ) {
+				return i;
+			}
+		}
+		return -1;
+	},
+
+	booleans = "checked|selected|async|autofocus|autoplay|controls|defer|disabled|hidden|ismap|loop|multiple|open|readonly|required|scoped",
+
+	// Regular expressions
+
+	// http://www.w3.org/TR/css3-selectors/#whitespace
+	whitespace = "[\\x20\\t\\r\\n\\f]",
+
+	// http://www.w3.org/TR/CSS21/syndata.html#value-def-identifier
+	identifier = "(?:\\\\.|[\\w-]|[^\\x00-\\xa0])+",
+
+	// Attribute selectors: http://www.w3.org/TR/selectors/#attribute-selectors
+	attributes = "\\[" + whitespace + "*(" + identifier + ")(?:" + whitespace +
+		// Operator (capture 2)
+		"*([*^$|!~]?=)" + whitespace +
+		// "Attribute values must be CSS identifiers [capture 5] or strings [capture 3 or capture 4]"
+		"*(?:'((?:\\\\.|[^\\\\'])*)'|\"((?:\\\\.|[^\\\\\"])*)\"|(" + identifier + "))|)" + whitespace +
+		"*\\]",
+
+	pseudos = ":(" + identifier + ")(?:\\((" +
+		// To reduce the number of selectors needing tokenize in the preFilter, prefer arguments:
+		// 1. quoted (capture 3; capture 4 or capture 5)
+		"('((?:\\\\.|[^\\\\'])*)'|\"((?:\\\\.|[^\\\\\"])*)\")|" +
+		// 2. simple (capture 6)
+		"((?:\\\\.|[^\\\\()[\\]]|" + attributes + ")*)|" +
+		// 3. anything else (capture 2)
+		".*" +
+		")\\)|)",
+
+	// Leading and non-escaped trailing whitespace, capturing some non-whitespace characters preceding the latter
+	rwhitespace = new RegExp( whitespace + "+", "g" ),
+	rtrim = new RegExp( "^" + whitespace + "+|((?:^|[^\\\\])(?:\\\\.)*)" + whitespace + "+$", "g" ),
+
+	rcomma = new RegExp( "^" + whitespace + "*," + whitespace + "*" ),
+	rcombinators = new RegExp( "^" + whitespace + "*([>+~]|" + whitespace + ")" + whitespace + "*" ),
+
+	rattributeQuotes = new RegExp( "=" + whitespace + "*([^\\]'\"]*?)" + whitespace + "*\\]", "g" ),
+
+	rpseudo = new RegExp( pseudos ),
+	ridentifier = new RegExp( "^" + identifier + "$" ),
+
+	matchExpr = {
+		"ID": new RegExp( "^#(" + identifier + ")" ),
+		"CLASS": new RegExp( "^\\.(" + identifier + ")" ),
+		"TAG": new RegExp( "^(" + identifier + "|[*])" ),
+		"ATTR": new RegExp( "^" + attributes ),
+		"PSEUDO": new RegExp( "^" + pseudos ),
+		"CHILD": new RegExp( "^:(only|first|last|nth|nth-last)-(child|of-type)(?:\\(" + whitespace +
+			"*(even|odd|(([+-]|)(\\d*)n|)" + whitespace + "*(?:([+-]|)" + whitespace +
+			"*(\\d+)|))" + whitespace + "*\\)|)", "i" ),
+		"bool": new RegExp( "^(?:" + booleans + ")$", "i" ),
+		// For use in libraries implementing .is()
+		// We use this for POS matching in `select`
+		"needsContext": new RegExp( "^" + whitespace + "*[>+~]|:(even|odd|eq|gt|lt|nth|first|last)(?:\\(" +
+			whitespace + "*((?:-\\d)?\\d*)" + whitespace + "*\\)|)(?=[^-]|$)", "i" )
+	},
+
+	rinputs = /^(?:input|select|textarea|button)$/i,
+	rheader = /^h\d$/i,
+
+	rnative = /^[^{]+\{\s*\[native \w/,
+
+	// Easily-parseable/retrievable ID or TAG or CLASS selectors
+	rquickExpr = /^(?:#([\w-]+)|(\w+)|\.([\w-]+))$/,
+
+	rsibling = /[+~]/,
+	rescape = /'|\\/g,
+
+	// CSS escapes http://www.w3.org/TR/CSS21/syndata.html#escaped-characters
+	runescape = new RegExp( "\\\\([\\da-f]{1,6}" + whitespace + "?|(" + whitespace + ")|.)", "ig" ),
+	funescape = function( _, escaped, escapedWhitespace ) {
+		var high = "0x" + escaped - 0x10000;
+		// NaN means non-codepoint
+		// Support: Firefox<24
+		// Workaround erroneous numeric interpretation of +"0x"
+		return high !== high || escapedWhitespace ?
+			escaped :
+			high < 0 ?
+				// BMP codepoint
+				String.fromCharCode( high + 0x10000 ) :
+				// Supplemental Plane codepoint (surrogate pair)
+				String.fromCharCode( high >> 10 | 0xD800, high & 0x3FF | 0xDC00 );
+	},
+
+	// Used for iframes
+	// See setDocument()
+	// Removing the function wrapper causes a "Permission Denied"
+	// error in IE
+	unloadHandler = function() {
+		setDocument();
+	};
+
+// Optimize for push.apply( _, NodeList )
+try {
+	push.apply(
+		(arr = slice.call( preferredDoc.childNodes )),
+		preferredDoc.childNodes
+	);
+	// Support: Android<4.0
+	// Detect silently failing push.apply
+	arr[ preferredDoc.childNodes.length ].nodeType;
+} catch ( e ) {
+	push = { apply: arr.length ?
+
+		// Leverage slice if possible
+		function( target, els ) {
+			push_native.apply( target, slice.call(els) );
+		} :
+
+		// Support: IE<9
+		// Otherwise append directly
+		function( target, els ) {
+			var j = target.length,
+				i = 0;
+			// Can't trust NodeList.length
+			while ( (target[j++] = els[i++]) ) {}
+			target.length = j - 1;
+		}
+	};
+}
+
+function Sizzle( selector, context, results, seed ) {
+	var m, i, elem, nid, nidselect, match, groups, newSelector,
+		newContext = context && context.ownerDocument,
+
+		// nodeType defaults to 9, since context defaults to document
+		nodeType = context ? context.nodeType : 9;
+
+	results = results || [];
+
+	// Return early from calls with invalid selector or context
+	if ( typeof selector !== "string" || !selector ||
+		nodeType !== 1 && nodeType !== 9 && nodeType !== 11 ) {
+
+		return results;
+	}
+
+	// Try to shortcut find operations (as opposed to filters) in HTML documents
+	if ( !seed ) {
+
+		if ( ( context ? context.ownerDocument || context : preferredDoc ) !== document ) {
+			setDocument( context );
+		}
+		context = context || document;
+
+		if ( documentIsHTML ) {
+
+			// If the selector is sufficiently simple, try using a "get*By*" DOM method
+			// (excepting DocumentFragment context, where the methods don't exist)
+			if ( nodeType !== 11 && (match = rquickExpr.exec( selector )) ) {
+
+				// ID selector
+				if ( (m = match[1]) ) {
+
+					// Document context
+					if ( nodeType === 9 ) {
+						if ( (elem = context.getElementById( m )) ) {
+
+							// Support: IE, Opera, Webkit
+							// TODO: identify versions
+							// getElementById can match elements by name instead of ID
+							if ( elem.id === m ) {
+								results.push( elem );
+								return results;
+							}
+						} else {
+							return results;
+						}
+
+					// Element context
+					} else {
+
+						// Support: IE, Opera, Webkit
+						// TODO: identify versions
+						// getElementById can match elements by name instead of ID
+						if ( newContext && (elem = newContext.getElementById( m )) &&
+							contains( context, elem ) &&
+							elem.id === m ) {
+
+							results.push( elem );
+							return results;
+						}
+					}
+
+				// Type selector
+				} else if ( match[2] ) {
+					push.apply( results, context.getElementsByTagName( selector ) );
+					return results;
+
+				// Class selector
+				} else if ( (m = match[3]) && support.getElementsByClassName &&
+					context.getElementsByClassName ) {
+
+					push.apply( results, context.getElementsByClassName( m ) );
+					return results;
+				}
+			}
+
+			// Take advantage of querySelectorAll
+			if ( support.qsa &&
+				!compilerCache[ selector + " " ] &&
+				(!rbuggyQSA || !rbuggyQSA.test( selector )) ) {
+
+				if ( nodeType !== 1 ) {
+					newContext = context;
+					newSelector = selector;
+
+				// qSA looks outside Element context, which is not what we want
+				// Thanks to Andrew Dupont for this workaround technique
+				// Support: IE <=8
+				// Exclude object elements
+				} else if ( context.nodeName.toLowerCase() !== "object" ) {
+
+					// Capture the context ID, setting it first if necessary
+					if ( (nid = context.getAttribute( "id" )) ) {
+						nid = nid.replace( rescape, "\\$&" );
+					} else {
+						context.setAttribute( "id", (nid = expando) );
+					}
+
+					// Prefix every selector in the list
+					groups = tokenize( selector );
+					i = groups.length;
+					nidselect = ridentifier.test( nid ) ? "#" + nid : "[id='" + nid + "']";
+					while ( i-- ) {
+						groups[i] = nidselect + " " + toSelector( groups[i] );
+					}
+					newSelector = groups.join( "," );
+
+					// Expand context for sibling selectors
+					newContext = rsibling.test( selector ) && testContext( context.parentNode ) ||
+						context;
+				}
+
+				if ( newSelector ) {
+					try {
+						push.apply( results,
+							newContext.querySelectorAll( newSelector )
+						);
+						return results;
+					} catch ( qsaError ) {
+					} finally {
+						if ( nid === expando ) {
+							context.removeAttribute( "id" );
+						}
+					}
+				}
+			}
+		}
+	}
+
+	// All others
+	return select( selector.replace( rtrim, "$1" ), context, results, seed );
+}
+
+/**
+ * Create key-value caches of limited size
+ * @returns {function(string, object)} Returns the Object data after storing it on itself with
+ *	property name the (space-suffixed) string and (if the cache is larger than Expr.cacheLength)
+ *	deleting the oldest entry
+ */
+function createCache() {
+	var keys = [];
+
+	function cache( key, value ) {
+		// Use (key + " ") to avoid collision with native prototype properties (see Issue #157)
+		if ( keys.push( key + " " ) > Expr.cacheLength ) {
+			// Only keep the most recent entries
+			delete cache[ keys.shift() ];
+		}
+		return (cache[ key + " " ] = value);
+	}
+	return cache;
+}
+
+/**
+ * Mark a function for special use by Sizzle
+ * @param {Function} fn The function to mark
+ */
+function markFunction( fn ) {
+	fn[ expando ] = true;
+	return fn;
+}
+
+/**
+ * Support testing using an element
+ * @param {Function} fn Passed the created div and expects a boolean result
+ */
+function assert( fn ) {
+	var div = document.createElement("div");
+
+	try {
+		return !!fn( div );
+	} catch (e) {
+		return false;
+	} finally {
+		// Remove from its parent by default
+		if ( div.parentNode ) {
+			div.parentNode.removeChild( div );
+		}
+		// release memory in IE
+		div = null;
+	}
+}
+
+/**
+ * Adds the same handler for all of the specified attrs
+ * @param {String} attrs Pipe-separated list of attributes
+ * @param {Function} handler The method that will be applied
+ */
+function addHandle( attrs, handler ) {
+	var arr = attrs.split("|"),
+		i = arr.length;
+
+	while ( i-- ) {
+		Expr.attrHandle[ arr[i] ] = handler;
+	}
+}
+
+/**
+ * Checks document order of two siblings
+ * @param {Element} a
+ * @param {Element} b
+ * @returns {Number} Returns less than 0 if a precedes b, greater than 0 if a follows b
+ */
+function siblingCheck( a, b ) {
+	var cur = b && a,
+		diff = cur && a.nodeType === 1 && b.nodeType === 1 &&
+			( ~b.sourceIndex || MAX_NEGATIVE ) -
+			( ~a.sourceIndex || MAX_NEGATIVE );
+
+	// Use IE sourceIndex if available on both nodes
+	if ( diff ) {
+		return diff;
+	}
+
+	// Check if b follows a
+	if ( cur ) {
+		while ( (cur = cur.nextSibling) ) {
+			if ( cur === b ) {
+				return -1;
+			}
+		}
+	}
+
+	return a ? 1 : -1;
+}
+
+/**
+ * Returns a function to use in pseudos for input types
+ * @param {String} type
+ */
+function createInputPseudo( type ) {
+	return function( elem ) {
+		var name = elem.nodeName.toLowerCase();
+		return name === "input" && elem.type === type;
+	};
+}
+
+/**
+ * Returns a function to use in pseudos for buttons
+ * @param {String} type
+ */
+function createButtonPseudo( type ) {
+	return function( elem ) {
+		var name = elem.nodeName.toLowerCase();
+		return (name === "input" || name === "button") && elem.type === type;
+	};
+}
+
+/**
+ * Returns a function to use in pseudos for positionals
+ * @param {Function} fn
+ */
+function createPositionalPseudo( fn ) {
+	return markFunction(function( argument ) {
+		argument = +argument;
+		return markFunction(function( seed, matches ) {
+			var j,
+				matchIndexes = fn( [], seed.length, argument ),
+				i = matchIndexes.length;
+
+			// Match elements found at the specified indexes
+			while ( i-- ) {
+				if ( seed[ (j = matchIndexes[i]) ] ) {
+					seed[j] = !(matches[j] = seed[j]);
+				}
+			}
+		});
+	});
+}
+
+/**
+ * Checks a node for validity as a Sizzle context
+ * @param {Element|Object=} context
+ * @returns {Element|Object|Boolean} The input node if acceptable, otherwise a falsy value
+ */
+function testContext( context ) {
+	return context && typeof context.getElementsByTagName !== "undefined" && context;
+}
+
+// Expose support vars for convenience
+support = Sizzle.support = {};
+
+/**
+ * Detects XML nodes
+ * @param {Element|Object} elem An element or a document
+ * @returns {Boolean} True iff elem is a non-HTML XML node
+ */
+isXML = Sizzle.isXML = function( elem ) {
+	// documentElement is verified for cases where it doesn't yet exist
+	// (such as loading iframes in IE - #4833)
+	var documentElement = elem && (elem.ownerDocument || elem).documentElement;
+	return documentElement ? documentElement.nodeName !== "HTML" : false;
+};
+
+/**
+ * Sets document-related variables once based on the current document
+ * @param {Element|Object} [doc] An element or document object to use to set the document
+ * @returns {Object} Returns the current document
+ */
+setDocument = Sizzle.setDocument = function( node ) {
+	var hasCompare, parent,
+		doc = node ? node.ownerDocument || node : preferredDoc;
+
+	// Return early if doc is invalid or already selected
+	if ( doc === document || doc.nodeType !== 9 || !doc.documentElement ) {
+		return document;
+	}
+
+	// Update global variables
+	document = doc;
+	docElem = document.documentElement;
+	documentIsHTML = !isXML( document );
+
+	// Support: IE 9-11, Edge
+	// Accessing iframe documents after unload throws "permission denied" errors (jQuery #13936)
+	if ( (parent = document.defaultView) && parent.top !== parent ) {
+		// Support: IE 11
+		if ( parent.addEventListener ) {
+			parent.addEventListener( "unload", unloadHandler, false );
+
+		// Support: IE 9 - 10 only
+		} else if ( parent.attachEvent ) {
+			parent.attachEvent( "onunload", unloadHandler );
+		}
+	}
+
+	/* Attributes
+	---------------------------------------------------------------------- */
+
+	// Support: IE<8
+	// Verify that getAttribute really returns attributes and not properties
+	// (excepting IE8 booleans)
+	support.attributes = assert(function( div ) {
+		div.className = "i";
+		return !div.getAttribute("className");
+	});
+
+	/* getElement(s)By*
+	---------------------------------------------------------------------- */
+
+	// Check if getElementsByTagName("*") returns only elements
+	support.getElementsByTagName = assert(function( div ) {
+		div.appendChild( document.createComment("") );
+		return !div.getElementsByTagName("*").length;
+	});
+
+	// Support: IE<9
+	support.getElementsByClassName = rnative.test( document.getElementsByClassName );
+
+	// Support: IE<10
+	// Check if getElementById returns elements by name
+	// The broken getElementById methods don't pick up programatically-set names,
+	// so use a roundabout getElementsByName test
+	support.getById = assert(function( div ) {
+		docElem.appendChild( div ).id = expando;
+		return !document.getElementsByName || !document.getElementsByName( expando ).length;
+	});
+
+	// ID find and filter
+	if ( support.getById ) {
+		Expr.find["ID"] = function( id, context ) {
+			if ( typeof context.getElementById !== "undefined" && documentIsHTML ) {
+				var m = context.getElementById( id );
+				return m ? [ m ] : [];
+			}
+		};
+		Expr.filter["ID"] = function( id ) {
+			var attrId = id.replace( runescape, funescape );
+			return function( elem ) {
+				return elem.getAttribute("id") === attrId;
+			};
+		};
+	} else {
+		// Support: IE6/7
+		// getElementById is not reliable as a find shortcut
+		delete Expr.find["ID"];
+
+		Expr.filter["ID"] =  function( id ) {
+			var attrId = id.replace( runescape, funescape );
+			return function( elem ) {
+				var node = typeof elem.getAttributeNode !== "undefined" &&
+					elem.getAttributeNode("id");
+				return node && node.value === attrId;
+			};
+		};
+	}
+
+	// Tag
+	Expr.find["TAG"] = support.getElementsByTagName ?
+		function( tag, context ) {
+			if ( typeof context.getElementsByTagName !== "undefined" ) {
+				return context.getElementsByTagName( tag );
+
+			// DocumentFragment nodes don't have gEBTN
+			} else if ( support.qsa ) {
+				return context.querySelectorAll( tag );
+			}
+		} :
+
+		function( tag, context ) {
+			var elem,
+				tmp = [],
+				i = 0,
+				// By happy coincidence, a (broken) gEBTN appears on DocumentFragment nodes too
+				results = context.getElementsByTagName( tag );
+
+			// Filter out possible comments
+			if ( tag === "*" ) {
+				while ( (elem = results[i++]) ) {
+					if ( elem.nodeType === 1 ) {
+						tmp.push( elem );
+					}
+				}
+
+				return tmp;
+			}
+			return results;
+		};
+
+	// Class
+	Expr.find["CLASS"] = support.getElementsByClassName && function( className, context ) {
+		if ( typeof context.getElementsByClassName !== "undefined" && documentIsHTML ) {
+			return context.getElementsByClassName( className );
+		}
+	};
+
+	/* QSA/matchesSelector
+	---------------------------------------------------------------------- */
+
+	// QSA and matchesSelector support
+
+	// matchesSelector(:active) reports false when true (IE9/Opera 11.5)
+	rbuggyMatches = [];
+
+	// qSa(:focus) reports false when true (Chrome 21)
+	// We allow this because of a bug in IE8/9 that throws an error
+	// whenever `document.activeElement` is accessed on an iframe
+	// So, we allow :focus to pass through QSA all the time to avoid the IE error
+	// See http://bugs.jquery.com/ticket/13378
+	rbuggyQSA = [];
+
+	if ( (support.qsa = rnative.test( document.querySelectorAll )) ) {
+		// Build QSA regex
+		// Regex strategy adopted from Diego Perini
+		assert(function( div ) {
+			// Select is set to empty string on purpose
+			// This is to test IE's treatment of not explicitly
+			// setting a boolean content attribute,
+			// since its presence should be enough
+			// http://bugs.jquery.com/ticket/12359
+			docElem.appendChild( div ).innerHTML = "<a id='" + expando + "'></a>" +
+				"<select id='" + expando + "-\r\\' msallowcapture=''>" +
+				"<option selected=''></option></select>";
+
+			// Support: IE8, Opera 11-12.16
+			// Nothing should be selected when empty strings follow ^= or $= or *=
+			// The test attribute must be unknown in Opera but "safe" for WinRT
+			// http://msdn.microsoft.com/en-us/library/ie/hh465388.aspx#attribute_section
+			if ( div.querySelectorAll("[msallowcapture^='']").length ) {
+				rbuggyQSA.push( "[*^$]=" + whitespace + "*(?:''|\"\")" );
+			}
+
+			// Support: IE8
+			// Boolean attributes and "value" are not treated correctly
+			if ( !div.querySelectorAll("[selected]").length ) {
+				rbuggyQSA.push( "\\[" + whitespace + "*(?:value|" + booleans + ")" );
+			}
+
+			// Support: Chrome<29, Android<4.4, Safari<7.0+, iOS<7.0+, PhantomJS<1.9.8+
+			if ( !div.querySelectorAll( "[id~=" + expando + "-]" ).length ) {
+				rbuggyQSA.push("~=");
+			}
+
+			// Webkit/Opera - :checked should return selected option elements
+			// http://www.w3.org/TR/2011/REC-css3-selectors-20110929/#checked
+			// IE8 throws error here and will not see later tests
+			if ( !div.querySelectorAll(":checked").length ) {
+				rbuggyQSA.push(":checked");
+			}
+
+			// Support: Safari 8+, iOS 8+
+			// https://bugs.webkit.org/show_bug.cgi?id=136851
+			// In-page `selector#id sibing-combinator selector` fails
+			if ( !div.querySelectorAll( "a#" + expando + "+*" ).length ) {
+				rbuggyQSA.push(".#.+[+~]");
+			}
+		});
+
+		assert(function( div ) {
+			// Support: Windows 8 Native Apps
+			// The type and name attributes are restricted during .innerHTML assignment
+			var input = document.createElement("input");
+			input.setAttribute( "type", "hidden" );
+			div.appendChild( input ).setAttribute( "name", "D" );
+
+			// Support: IE8
+			// Enforce case-sensitivity of name attribute
+			if ( div.querySelectorAll("[name=d]").length ) {
+				rbuggyQSA.push( "name" + whitespace + "*[*^$|!~]?=" );
+			}
+
+			// FF 3.5 - :enabled/:disabled and hidden elements (hidden elements are still enabled)
+			// IE8 throws error here and will not see later tests
+			if ( !div.querySelectorAll(":enabled").length ) {
+				rbuggyQSA.push( ":enabled", ":disabled" );
+			}
+
+			// Opera 10-11 does not throw on post-comma invalid pseudos
+			div.querySelectorAll("*,:x");
+			rbuggyQSA.push(",.*:");
+		});
+	}
+
+	if ( (support.matchesSelector = rnative.test( (matches = docElem.matches ||
+		docElem.webkitMatchesSelector ||
+		docElem.mozMatchesSelector ||
+		docElem.oMatchesSelector ||
+		docElem.msMatchesSelector) )) ) {
+
+		assert(function( div ) {
+			// Check to see if it's possible to do matchesSelector
+			// on a disconnected node (IE 9)
+			support.disconnectedMatch = matches.call( div, "div" );
+
+			// This should fail with an exception
+			// Gecko does not error, returns false instead
+			matches.call( div, "[s!='']:x" );
+			rbuggyMatches.push( "!=", pseudos );
+		});
+	}
+
+	rbuggyQSA = rbuggyQSA.length && new RegExp( rbuggyQSA.join("|") );
+	rbuggyMatches = rbuggyMatches.length && new RegExp( rbuggyMatches.join("|") );
+
+	/* Contains
+	---------------------------------------------------------------------- */
+	hasCompare = rnative.test( docElem.compareDocumentPosition );
+
+	// Element contains another
+	// Purposefully self-exclusive
+	// As in, an element does not contain itself
+	contains = hasCompare || rnative.test( docElem.contains ) ?
+		function( a, b ) {
+			var adown = a.nodeType === 9 ? a.documentElement : a,
+				bup = b && b.parentNode;
+			return a === bup || !!( bup && bup.nodeType === 1 && (
+				adown.contains ?
+					adown.contains( bup ) :
+					a.compareDocumentPosition && a.compareDocumentPosition( bup ) & 16
+			));
+		} :
+		function( a, b ) {
+			if ( b ) {
+				while ( (b = b.parentNode) ) {
+					if ( b === a ) {
+						return true;
+					}
+				}
+			}
+			return false;
+		};
+
+	/* Sorting
+	---------------------------------------------------------------------- */
+
+	// Document order sorting
+	sortOrder = hasCompare ?
+	function( a, b ) {
+
+		// Flag for duplicate removal
+		if ( a === b ) {
+			hasDuplicate = true;
+			return 0;
+		}
+
+		// Sort on method existence if only one input has compareDocumentPosition
+		var compare = !a.compareDocumentPosition - !b.compareDocumentPosition;
+		if ( compare ) {
+			return compare;
+		}
+
+		// Calculate position if both inputs belong to the same document
+		compare = ( a.ownerDocument || a ) === ( b.ownerDocument || b ) ?
+			a.compareDocumentPosition( b ) :
+
+			// Otherwise we know they are disconnected
+			1;
+
+		// Disconnected nodes
+		if ( compare & 1 ||
+			(!support.sortDetached && b.compareDocumentPosition( a ) === compare) ) {
+
+			// Choose the first element that is related to our preferred document
+			if ( a === document || a.ownerDocument === preferredDoc && contains(preferredDoc, a) ) {
+				return -1;
+			}
+			if ( b === document || b.ownerDocument === preferredDoc && contains(preferredDoc, b) ) {
+				return 1;
+			}
+
+			// Maintain original order
+			return sortInput ?
+				( indexOf( sortInput, a ) - indexOf( sortInput, b ) ) :
+				0;
+		}
+
+		return compare & 4 ? -1 : 1;
+	} :
+	function( a, b ) {
+		// Exit early if the nodes are identical
+		if ( a === b ) {
+			hasDuplicate = true;
+			return 0;
+		}
+
+		var cur,
+			i = 0,
+			aup = a.parentNode,
+			bup = b.parentNode,
+			ap = [ a ],
+			bp = [ b ];
+
+		// Parentless nodes are either documents or disconnected
+		if ( !aup || !bup ) {
+			return a === document ? -1 :
+				b === document ? 1 :
+				aup ? -1 :
+				bup ? 1 :
+				sortInput ?
+				( indexOf( sortInput, a ) - indexOf( sortInput, b ) ) :
+				0;
+
+		// If the nodes are siblings, we can do a quick check
+		} else if ( aup === bup ) {
+			return siblingCheck( a, b );
+		}
+
+		// Otherwise we need full lists of their ancestors for comparison
+		cur = a;
+		while ( (cur = cur.parentNode) ) {
+			ap.unshift( cur );
+		}
+		cur = b;
+		while ( (cur = cur.parentNode) ) {
+			bp.unshift( cur );
+		}
+
+		// Walk down the tree looking for a discrepancy
+		while ( ap[i] === bp[i] ) {
+			i++;
+		}
+
+		return i ?
+			// Do a sibling check if the nodes have a common ancestor
+			siblingCheck( ap[i], bp[i] ) :
+
+			// Otherwise nodes in our document sort first
+			ap[i] === preferredDoc ? -1 :
+			bp[i] === preferredDoc ? 1 :
+			0;
+	};
+
+	return document;
+};
+
+Sizzle.matches = function( expr, elements ) {
+	return Sizzle( expr, null, null, elements );
+};
+
+Sizzle.matchesSelector = function( elem, expr ) {
+	// Set document vars if needed
+	if ( ( elem.ownerDocument || elem ) !== document ) {
+		setDocument( elem );
+	}
+
+	// Make sure that attribute selectors are quoted
+	expr = expr.replace( rattributeQuotes, "='$1']" );
+
+	if ( support.matchesSelector && documentIsHTML &&
+		!compilerCache[ expr + " " ] &&
+		( !rbuggyMatches || !rbuggyMatches.test( expr ) ) &&
+		( !rbuggyQSA     || !rbuggyQSA.test( expr ) ) ) {
+
+		try {
+			var ret = matches.call( elem, expr );
+
+			// IE 9's matchesSelector returns false on disconnected nodes
+			if ( ret || support.disconnectedMatch ||
+					// As well, disconnected nodes are said to be in a document
+					// fragment in IE 9
+					elem.document && elem.document.nodeType !== 11 ) {
+				return ret;
+			}
+		} catch (e) {}
+	}
+
+	return Sizzle( expr, document, null, [ elem ] ).length > 0;
+};
+
+Sizzle.contains = function( context, elem ) {
+	// Set document vars if needed
+	if ( ( context.ownerDocument || context ) !== document ) {
+		setDocument( context );
+	}
+	return contains( context, elem );
+};
+
+Sizzle.attr = function( elem, name ) {
+	// Set document vars if needed
+	if ( ( elem.ownerDocument || elem ) !== document ) {
+		setDocument( elem );
+	}
+
+	var fn = Expr.attrHandle[ name.toLowerCase() ],
+		// Don't get fooled by Object.prototype properties (jQuery #13807)
+		val = fn && hasOwn.call( Expr.attrHandle, name.toLowerCase() ) ?
+			fn( elem, name, !documentIsHTML ) :
+			undefined;
+
+	return val !== undefined ?
+		val :
+		support.attributes || !documentIsHTML ?
+			elem.getAttribute( name ) :
+			(val = elem.getAttributeNode(name)) && val.specified ?
+				val.value :
+				null;
+};
+
+Sizzle.error = function( msg ) {
+	throw new Error( "Syntax error, unrecognized expression: " + msg );
+};
+
+/**
+ * Document sorting and removing duplicates
+ * @param {ArrayLike} results
+ */
+Sizzle.uniqueSort = function( results ) {
+	var elem,
+		duplicates = [],
+		j = 0,
+		i = 0;
+
+	// Unless we *know* we can detect duplicates, assume their presence
+	hasDuplicate = !support.detectDuplicates;
+	sortInput = !support.sortStable && results.slice( 0 );
+	results.sort( sortOrder );
+
+	if ( hasDuplicate ) {
+		while ( (elem = results[i++]) ) {
+			if ( elem === results[ i ] ) {
+				j = duplicates.push( i );
+			}
+		}
+		while ( j-- ) {
+			results.splice( duplicates[ j ], 1 );
+		}
+	}
+
+	// Clear input after sorting to release objects
+	// See https://github.com/jquery/sizzle/pull/225
+	sortInput = null;
+
+	return results;
+};
+
+/**
+ * Utility function for retrieving the text value of an array of DOM nodes
+ * @param {Array|Element} elem
+ */
+getText = Sizzle.getText = function( elem ) {
+	var node,
+		ret = "",
+		i = 0,
+		nodeType = elem.nodeType;
+
+	if ( !nodeType ) {
+		// If no nodeType, this is expected to be an array
+		while ( (node = elem[i++]) ) {
+			// Do not traverse comment nodes
+			ret += getText( node );
+		}
+	} else if ( nodeType === 1 || nodeType === 9 || nodeType === 11 ) {
+		// Use textContent for elements
+		// innerText usage removed for consistency of new lines (jQuery #11153)
+		if ( typeof elem.textContent === "string" ) {
+			return elem.textContent;
+		} else {
+			// Traverse its children
+			for ( elem = elem.firstChild; elem; elem = elem.nextSibling ) {
+				ret += getText( elem );
+			}
+		}
+	} else if ( nodeType === 3 || nodeType === 4 ) {
+		return elem.nodeValue;
+	}
+	// Do not include comment or processing instruction nodes
+
+	return ret;
+};
+
+Expr = Sizzle.selectors = {
+
+	// Can be adjusted by the user
+	cacheLength: 50,
+
+	createPseudo: markFunction,
+
+	match: matchExpr,
+
+	attrHandle: {},
+
+	find: {},
+
+	relative: {
+		">": { dir: "parentNode", first: true },
+		" ": { dir: "parentNode" },
+		"+": { dir: "previousSibling", first: true },
+		"~": { dir: "previousSibling" }
+	},
+
+	preFilter: {
+		"ATTR": function( match ) {
+			match[1] = match[1].replace( runescape, funescape );
+
+			// Move the given value to match[3] whether quoted or unquoted
+			match[3] = ( match[3] || match[4] || match[5] || "" ).replace( runescape, funescape );
+
+			if ( match[2] === "~=" ) {
+				match[3] = " " + match[3] + " ";
+			}
+
+			return match.slice( 0, 4 );
+		},
+
+		"CHILD": function( match ) {
+			/* matches from matchExpr["CHILD"]
+				1 type (only|nth|...)
+				2 what (child|of-type)
+				3 argument (even|odd|\d*|\d*n([+-]\d+)?|...)
+				4 xn-component of xn+y argument ([+-]?\d*n|)
+				5 sign of xn-component
+				6 x of xn-component
+				7 sign of y-component
+				8 y of y-component
+			*/
+			match[1] = match[1].toLowerCase();
+
+			if ( match[1].slice( 0, 3 ) === "nth" ) {
+				// nth-* requires argument
+				if ( !match[3] ) {
+					Sizzle.error( match[0] );
+				}
+
+				// numeric x and y parameters for Expr.filter.CHILD
+				// remember that false/true cast respectively to 0/1
+				match[4] = +( match[4] ? match[5] + (match[6] || 1) : 2 * ( match[3] === "even" || match[3] === "odd" ) );
+				match[5] = +( ( match[7] + match[8] ) || match[3] === "odd" );
+
+			// other types prohibit arguments
+			} else if ( match[3] ) {
+				Sizzle.error( match[0] );
+			}
+
+			return match;
+		},
+
+		"PSEUDO": function( match ) {
+			var excess,
+				unquoted = !match[6] && match[2];
+
+			if ( matchExpr["CHILD"].test( match[0] ) ) {
+				return null;
+			}
+
+			// Accept quoted arguments as-is
+			if ( match[3] ) {
+				match[2] = match[4] || match[5] || "";
+
+			// Strip excess characters from unquoted arguments
+			} else if ( unquoted && rpseudo.test( unquoted ) &&
+				// Get excess from tokenize (recursively)
+				(excess = tokenize( unquoted, true )) &&
+				// advance to the next closing parenthesis
+				(excess = unquoted.indexOf( ")", unquoted.length - excess ) - unquoted.length) ) {
+
+				// excess is a negative index
+				match[0] = match[0].slice( 0, excess );
+				match[2] = unquoted.slice( 0, excess );
+			}
+
+			// Return only captures needed by the pseudo filter method (type and argument)
+			return match.slice( 0, 3 );
+		}
+	},
+
+	filter: {
+
+		"TAG": function( nodeNameSelector ) {
+			var nodeName = nodeNameSelector.replace( runescape, funescape ).toLowerCase();
+			return nodeNameSelector === "*" ?
+				function() { return true; } :
+				function( elem ) {
+					return elem.nodeName && elem.nodeName.toLowerCase() === nodeName;
+				};
+		},
+
+		"CLASS": function( className ) {
+			var pattern = classCache[ className + " " ];
+
+			return pattern ||
+				(pattern = new RegExp( "(^|" + whitespace + ")" + className + "(" + whitespace + "|$)" )) &&
+				classCache( className, function( elem ) {
+					return pattern.test( typeof elem.className === "string" && elem.className || typeof elem.getAttribute !== "undefined" && elem.getAttribute("class") || "" );
+				});
+		},
+
+		"ATTR": function( name, operator, check ) {
+			return function( elem ) {
+				var result = Sizzle.attr( elem, name );
+
+				if ( result == null ) {
+					return operator === "!=";
+				}
+				if ( !operator ) {
+					return true;
+				}
+
+				result += "";
+
+				return operator === "=" ? result === check :
+					operator === "!=" ? result !== check :
+					operator === "^=" ? check && result.indexOf( check ) === 0 :
+					operator === "*=" ? check && result.indexOf( check ) > -1 :
+					operator === "$=" ? check && result.slice( -check.length ) === check :
+					operator === "~=" ? ( " " + result.replace( rwhitespace, " " ) + " " ).indexOf( check ) > -1 :
+					operator === "|=" ? result === check || result.slice( 0, check.length + 1 ) === check + "-" :
+					false;
+			};
+		},
+
+		"CHILD": function( type, what, argument, first, last ) {
+			var simple = type.slice( 0, 3 ) !== "nth",
+				forward = type.slice( -4 ) !== "last",
+				ofType = what === "of-type";
+
+			return first === 1 && last === 0 ?
+
+				// Shortcut for :nth-*(n)
+				function( elem ) {
+					return !!elem.parentNode;
+				} :
+
+				function( elem, context, xml ) {
+					var cache, uniqueCache, outerCache, node, nodeIndex, start,
+						dir = simple !== forward ? "nextSibling" : "previousSibling",
+						parent = elem.parentNode,
+						name = ofType && elem.nodeName.toLowerCase(),
+						useCache = !xml && !ofType,
+						diff = false;
+
+					if ( parent ) {
+
+						// :(first|last|only)-(child|of-type)
+						if ( simple ) {
+							while ( dir ) {
+								node = elem;
+								while ( (node = node[ dir ]) ) {
+									if ( ofType ?
+										node.nodeName.toLowerCase() === name :
+										node.nodeType === 1 ) {
+
+										return false;
+									}
+								}
+								// Reverse direction for :only-* (if we haven't yet done so)
+								start = dir = type === "only" && !start && "nextSibling";
+							}
+							return true;
+						}
+
+						start = [ forward ? parent.firstChild : parent.lastChild ];
+
+						// non-xml :nth-child(...) stores cache data on `parent`
+						if ( forward && useCache ) {
+
+							// Seek `elem` from a previously-cached index
+
+							// ...in a gzip-friendly way
+							node = parent;
+							outerCache = node[ expando ] || (node[ expando ] = {});
+
+							// Support: IE <9 only
+							// Defend against cloned attroperties (jQuery gh-1709)
+							uniqueCache = outerCache[ node.uniqueID ] ||
+								(outerCache[ node.uniqueID ] = {});
+
+							cache = uniqueCache[ type ] || [];
+							nodeIndex = cache[ 0 ] === dirruns && cache[ 1 ];
+							diff = nodeIndex && cache[ 2 ];
+							node = nodeIndex && parent.childNodes[ nodeIndex ];
+
+							while ( (node = ++nodeIndex && node && node[ dir ] ||
+
+								// Fallback to seeking `elem` from the start
+								(diff = nodeIndex = 0) || start.pop()) ) {
+
+								// When found, cache indexes on `parent` and break
+								if ( node.nodeType === 1 && ++diff && node === elem ) {
+									uniqueCache[ type ] = [ dirruns, nodeIndex, diff ];
+									break;
+								}
+							}
+
+						} else {
+							// Use previously-cached element index if available
+							if ( useCache ) {
+								// ...in a gzip-friendly way
+								node = elem;
+								outerCache = node[ expando ] || (node[ expando ] = {});
+
+								// Support: IE <9 only
+								// Defend against cloned attroperties (jQuery gh-1709)
+								uniqueCache = outerCache[ node.uniqueID ] ||
+									(outerCache[ node.uniqueID ] = {});
+
+								cache = uniqueCache[ type ] || [];
+								nodeIndex = cache[ 0 ] === dirruns && cache[ 1 ];
+								diff = nodeIndex;
+							}
+
+							// xml :nth-child(...)
+							// or :nth-last-child(...) or :nth(-last)?-of-type(...)
+							if ( diff === false ) {
+								// Use the same loop as above to seek `elem` from the start
+								while ( (node = ++nodeIndex && node && node[ dir ] ||
+									(diff = nodeIndex = 0) || start.pop()) ) {
+
+									if ( ( ofType ?
+										node.nodeName.toLowerCase() === name :
+										node.nodeType === 1 ) &&
+										++diff ) {
+
+										// Cache the index of each encountered element
+										if ( useCache ) {
+											outerCache = node[ expando ] || (node[ expando ] = {});
+
+											// Support: IE <9 only
+											// Defend against cloned attroperties (jQuery gh-1709)
+											uniqueCache = outerCache[ node.uniqueID ] ||
+												(outerCache[ node.uniqueID ] = {});
+
+											uniqueCache[ type ] = [ dirruns, diff ];
+										}
+
+										if ( node === elem ) {
+											break;
+										}
+									}
+								}
+							}
+						}
+
+						// Incorporate the offset, then check against cycle size
+						diff -= last;
+						return diff === first || ( diff % first === 0 && diff / first >= 0 );
+					}
+				};
+		},
+
+		"PSEUDO": function( pseudo, argument ) {
+			// pseudo-class names are case-insensitive
+			// http://www.w3.org/TR/selectors/#pseudo-classes
+			// Prioritize by case sensitivity in case custom pseudos are added with uppercase letters
+			// Remember that setFilters inherits from pseudos
+			var args,
+				fn = Expr.pseudos[ pseudo ] || Expr.setFilters[ pseudo.toLowerCase() ] ||
+					Sizzle.error( "unsupported pseudo: " + pseudo );
+
+			// The user may use createPseudo to indicate that
+			// arguments are needed to create the filter function
+			// just as Sizzle does
+			if ( fn[ expando ] ) {
+				return fn( argument );
+			}
+
+			// But maintain support for old signatures
+			if ( fn.length > 1 ) {
+				args = [ pseudo, pseudo, "", argument ];
+				return Expr.setFilters.hasOwnProperty( pseudo.toLowerCase() ) ?
+					markFunction(function( seed, matches ) {
+						var idx,
+							matched = fn( seed, argument ),
+							i = matched.length;
+						while ( i-- ) {
+							idx = indexOf( seed, matched[i] );
+							seed[ idx ] = !( matches[ idx ] = matched[i] );
+						}
+					}) :
+					function( elem ) {
+						return fn( elem, 0, args );
+					};
+			}
+
+			return fn;
+		}
+	},
+
+	pseudos: {
+		// Potentially complex pseudos
+		"not": markFunction(function( selector ) {
+			// Trim the selector passed to compile
+			// to avoid treating leading and trailing
+			// spaces as combinators
+			var input = [],
+				results = [],
+				matcher = compile( selector.replace( rtrim, "$1" ) );
+
+			return matcher[ expando ] ?
+				markFunction(function( seed, matches, context, xml ) {
+					var elem,
+						unmatched = matcher( seed, null, xml, [] ),
+						i = seed.length;
+
+					// Match elements unmatched by `matcher`
+					while ( i-- ) {
+						if ( (elem = unmatched[i]) ) {
+							seed[i] = !(matches[i] = elem);
+						}
+					}
+				}) :
+				function( elem, context, xml ) {
+					input[0] = elem;
+					matcher( input, null, xml, results );
+					// Don't keep the element (issue #299)
+					input[0] = null;
+					return !results.pop();
+				};
+		}),
+
+		"has": markFunction(function( selector ) {
+			return function( elem ) {
+				return Sizzle( selector, elem ).length > 0;
+			};
+		}),
+
+		"contains": markFunction(function( text ) {
+			text = text.replace( runescape, funescape );
+			return function( elem ) {
+				return ( elem.textContent || elem.innerText || getText( elem ) ).indexOf( text ) > -1;
+			};
+		}),
+
+		// "Whether an element is represented by a :lang() selector
+		// is based solely on the element's language value
+		// being equal to the identifier C,
+		// or beginning with the identifier C immediately followed by "-".
+		// The matching of C against the element's language value is performed case-insensitively.
+		// The identifier C does not have to be a valid language name."
+		// http://www.w3.org/TR/selectors/#lang-pseudo
+		"lang": markFunction( function( lang ) {
+			// lang value must be a valid identifier
+			if ( !ridentifier.test(lang || "") ) {
+				Sizzle.error( "unsupported lang: " + lang );
+			}
+			lang = lang.replace( runescape, funescape ).toLowerCase();
+			return function( elem ) {
+				var elemLang;
+				do {
+					if ( (elemLang = documentIsHTML ?
+						elem.lang :
+						elem.getAttribute("xml:lang") || elem.getAttribute("lang")) ) {
+
+						elemLang = elemLang.toLowerCase();
+						return elemLang === lang || elemLang.indexOf( lang + "-" ) === 0;
+					}
+				} while ( (elem = elem.parentNode) && elem.nodeType === 1 );
+				return false;
+			};
+		}),
+
+		// Miscellaneous
+		"target": function( elem ) {
+			var hash = window.location && window.location.hash;
+			return hash && hash.slice( 1 ) === elem.id;
+		},
+
+		"root": function( elem ) {
+			return elem === docElem;
+		},
+
+		"focus": function( elem ) {
+			return elem === document.activeElement && (!document.hasFocus || document.hasFocus()) && !!(elem.type || elem.href || ~elem.tabIndex);
+		},
+
+		// Boolean properties
+		"enabled": function( elem ) {
+			return elem.disabled === false;
+		},
+
+		"disabled": function( elem ) {
+			return elem.disabled === true;
+		},
+
+		"checked": function( elem ) {
+			// In CSS3, :checked should return both checked and selected elements
+			// http://www.w3.org/TR/2011/REC-css3-selectors-20110929/#checked
+			var nodeName = elem.nodeName.toLowerCase();
+			return (nodeName === "input" && !!elem.checked) || (nodeName === "option" && !!elem.selected);
+		},
+
+		"selected": function( elem ) {
+			// Accessing this property makes selected-by-default
+			// options in Safari work properly
+			if ( elem.parentNode ) {
+				elem.parentNode.selectedIndex;
+			}
+
+			return elem.selected === true;
+		},
+
+		// Contents
+		"empty": function( elem ) {
+			// http://www.w3.org/TR/selectors/#empty-pseudo
+			// :empty is negated by element (1) or content nodes (text: 3; cdata: 4; entity ref: 5),
+			//   but not by others (comment: 8; processing instruction: 7; etc.)
+			// nodeType < 6 works because attributes (2) do not appear as children
+			for ( elem = elem.firstChild; elem; elem = elem.nextSibling ) {
+				if ( elem.nodeType < 6 ) {
+					return false;
+				}
+			}
+			return true;
+		},
+
+		"parent": function( elem ) {
+			return !Expr.pseudos["empty"]( elem );
+		},
+
+		// Element/input types
+		"header": function( elem ) {
+			return rheader.test( elem.nodeName );
+		},
+
+		"input": function( elem ) {
+			return rinputs.test( elem.nodeName );
+		},
+
+		"button": function( elem ) {
+			var name = elem.nodeName.toLowerCase();
+			return name === "input" && elem.type === "button" || name === "button";
+		},
+
+		"text": function( elem ) {
+			var attr;
+			return elem.nodeName.toLowerCase() === "input" &&
+				elem.type === "text" &&
+
+				// Support: IE<8
+				// New HTML5 attribute values (e.g., "search") appear with elem.type === "text"
+				( (attr = elem.getAttribute("type")) == null || attr.toLowerCase() === "text" );
+		},
+
+		// Position-in-collection
+		"first": createPositionalPseudo(function() {
+			return [ 0 ];
+		}),
+
+		"last": createPositionalPseudo(function( matchIndexes, length ) {
+			return [ length - 1 ];
+		}),
+
+		"eq": createPositionalPseudo(function( matchIndexes, length, argument ) {
+			return [ argument < 0 ? argument + length : argument ];
+		}),
+
+		"even": createPositionalPseudo(function( matchIndexes, length ) {
+			var i = 0;
+			for ( ; i < length; i += 2 ) {
+				matchIndexes.push( i );
+			}
+			return matchIndexes;
+		}),
+
+		"odd": createPositionalPseudo(function( matchIndexes, length ) {
+			var i = 1;
+			for ( ; i < length; i += 2 ) {
+				matchIndexes.push( i );
+			}
+			return matchIndexes;
+		}),
+
+		"lt": createPositionalPseudo(function( matchIndexes, length, argument ) {
+			var i = argument < 0 ? argument + length : argument;
+			for ( ; --i >= 0; ) {
+				matchIndexes.push( i );
+			}
+			return matchIndexes;
+		}),
+
+		"gt": createPositionalPseudo(function( matchIndexes, length, argument ) {
+			var i = argument < 0 ? argument + length : argument;
+			for ( ; ++i < length; ) {
+				matchIndexes.push( i );
+			}
+			return matchIndexes;
+		})
+	}
+};
+
+Expr.pseudos["nth"] = Expr.pseudos["eq"];
+
+// Add button/input type pseudos
+for ( i in { radio: true, checkbox: true, file: true, password: true, image: true } ) {
+	Expr.pseudos[ i ] = createInputPseudo( i );
+}
+for ( i in { submit: true, reset: true } ) {
+	Expr.pseudos[ i ] = createButtonPseudo( i );
+}
+
+// Easy API for creating new setFilters
+function setFilters() {}
+setFilters.prototype = Expr.filters = Expr.pseudos;
+Expr.setFilters = new setFilters();
+
+tokenize = Sizzle.tokenize = function( selector, parseOnly ) {
+	var matched, match, tokens, type,
+		soFar, groups, preFilters,
+		cached = tokenCache[ selector + " " ];
+
+	if ( cached ) {
+		return parseOnly ? 0 : cached.slice( 0 );
+	}
+
+	soFar = selector;
+	groups = [];
+	preFilters = Expr.preFilter;
+
+	while ( soFar ) {
+
+		// Comma and first run
+		if ( !matched || (match = rcomma.exec( soFar )) ) {
+			if ( match ) {
+				// Don't consume trailing commas as valid
+				soFar = soFar.slice( match[0].length ) || soFar;
+			}
+			groups.push( (tokens = []) );
+		}
+
+		matched = false;
+
+		// Combinators
+		if ( (match = rcombinators.exec( soFar )) ) {
+			matched = match.shift();
+			tokens.push({
+				value: matched,
+				// Cast descendant combinators to space
+				type: match[0].replace( rtrim, " " )
+			});
+			soFar = soFar.slice( matched.length );
+		}
+
+		// Filters
+		for ( type in Expr.filter ) {
+			if ( (match = matchExpr[ type ].exec( soFar )) && (!preFilters[ type ] ||
+				(match = preFilters[ type ]( match ))) ) {
+				matched = match.shift();
+				tokens.push({
+					value: matched,
+					type: type,
+					matches: match
+				});
+				soFar = soFar.slice( matched.length );
+			}
+		}
+
+		if ( !matched ) {
+			break;
+		}
+	}
+
+	// Return the length of the invalid excess
+	// if we're just parsing
+	// Otherwise, throw an error or return tokens
+	return parseOnly ?
+		soFar.length :
+		soFar ?
+			Sizzle.error( selector ) :
+			// Cache the tokens
+			tokenCache( selector, groups ).slice( 0 );
+};
+
+function toSelector( tokens ) {
+	var i = 0,
+		len = tokens.length,
+		selector = "";
+	for ( ; i < len; i++ ) {
+		selector += tokens[i].value;
+	}
+	return selector;
+}
+
+function addCombinator( matcher, combinator, base ) {
+	var dir = combinator.dir,
+		checkNonElements = base && dir === "parentNode",
+		doneName = done++;
+
+	return combinator.first ?
+		// Check against closest ancestor/preceding element
+		function( elem, context, xml ) {
+			while ( (elem = elem[ dir ]) ) {
+				if ( elem.nodeType === 1 || checkNonElements ) {
+					return matcher( elem, context, xml );
+				}
+			}
+		} :
+
+		// Check against all ancestor/preceding elements
+		function( elem, context, xml ) {
+			var oldCache, uniqueCache, outerCache,
+				newCache = [ dirruns, doneName ];
+
+			// We can't set arbitrary data on XML nodes, so they don't benefit from combinator caching
+			if ( xml ) {
+				while ( (elem = elem[ dir ]) ) {
+					if ( elem.nodeType === 1 || checkNonElements ) {
+						if ( matcher( elem, context, xml ) ) {
+							return true;
+						}
+					}
+				}
+			} else {
+				while ( (elem = elem[ dir ]) ) {
+					if ( elem.nodeType === 1 || checkNonElements ) {
+						outerCache = elem[ expando ] || (elem[ expando ] = {});
+
+						// Support: IE <9 only
+						// Defend against cloned attroperties (jQuery gh-1709)
+						uniqueCache = outerCache[ elem.uniqueID ] || (outerCache[ elem.uniqueID ] = {});
+
+						if ( (oldCache = uniqueCache[ dir ]) &&
+							oldCache[ 0 ] === dirruns && oldCache[ 1 ] === doneName ) {
+
+							// Assign to newCache so results back-propagate to previous elements
+							return (newCache[ 2 ] = oldCache[ 2 ]);
+						} else {
+							// Reuse newcache so results back-propagate to previous elements
+							uniqueCache[ dir ] = newCache;
+
+							// A match means we're done; a fail means we have to keep checking
+							if ( (newCache[ 2 ] = matcher( elem, context, xml )) ) {
+								return true;
+							}
+						}
+					}
+				}
+			}
+		};
+}
+
+function elementMatcher( matchers ) {
+	return matchers.length > 1 ?
+		function( elem, context, xml ) {
+			var i = matchers.length;
+			while ( i-- ) {
+				if ( !matchers[i]( elem, context, xml ) ) {
+					return false;
+				}
+			}
+			return true;
+		} :
+		matchers[0];
+}
+
+function multipleContexts( selector, contexts, results ) {
+	var i = 0,
+		len = contexts.length;
+	for ( ; i < len; i++ ) {
+		Sizzle( selector, contexts[i], results );
+	}
+	return results;
+}
+
+function condense( unmatched, map, filter, context, xml ) {
+	var elem,
+		newUnmatched = [],
+		i = 0,
+		len = unmatched.length,
+		mapped = map != null;
+
+	for ( ; i < len; i++ ) {
+		if ( (elem = unmatched[i]) ) {
+			if ( !filter || filter( elem, context, xml ) ) {
+				newUnmatched.push( elem );
+				if ( mapped ) {
+					map.push( i );
+				}
+			}
+		}
+	}
+
+	return newUnmatched;
+}
+
+function setMatcher( preFilter, selector, matcher, postFilter, postFinder, postSelector ) {
+	if ( postFilter && !postFilter[ expando ] ) {
+		postFilter = setMatcher( postFilter );
+	}
+	if ( postFinder && !postFinder[ expando ] ) {
+		postFinder = setMatcher( postFinder, postSelector );
+	}
+	return markFunction(function( seed, results, context, xml ) {
+		var temp, i, elem,
+			preMap = [],
+			postMap = [],
+			preexisting = results.length,
+
+			// Get initial elements from seed or context
+			elems = seed || multipleContexts( selector || "*", context.nodeType ? [ context ] : context, [] ),
+
+			// Prefilter to get matcher input, preserving a map for seed-results synchronization
+			matcherIn = preFilter && ( seed || !selector ) ?
+				condense( elems, preMap, preFilter, context, xml ) :
+				elems,
+
+			matcherOut = matcher ?
+				// If we have a postFinder, or filtered seed, or non-seed postFilter or preexisting results,
+				postFinder || ( seed ? preFilter : preexisting || postFilter ) ?
+
+					// ...intermediate processing is necessary
+					[] :
+
+					// ...otherwise use results directly
+					results :
+				matcherIn;
+
+		// Find primary matches
+		if ( matcher ) {
+			matcher( matcherIn, matcherOut, context, xml );
+		}
+
+		// Apply postFilter
+		if ( postFilter ) {
+			temp = condense( matcherOut, postMap );
+			postFilter( temp, [], context, xml );
+
+			// Un-match failing elements by moving them back to matcherIn
+			i = temp.length;
+			while ( i-- ) {
+				if ( (elem = temp[i]) ) {
+					matcherOut[ postMap[i] ] = !(matcherIn[ postMap[i] ] = elem);
+				}
+			}
+		}
+
+		if ( seed ) {
+			if ( postFinder || preFilter ) {
+				if ( postFinder ) {
+					// Get the final matcherOut by condensing this intermediate into postFinder contexts
+					temp = [];
+					i = matcherOut.length;
+					while ( i-- ) {
+						if ( (elem = matcherOut[i]) ) {
+							// Restore matcherIn since elem is not yet a final match
+							temp.push( (matcherIn[i] = elem) );
+						}
+					}
+					postFinder( null, (matcherOut = []), temp, xml );
+				}
+
+				// Move matched elements from seed to results to keep them synchronized
+				i = matcherOut.length;
+				while ( i-- ) {
+					if ( (elem = matcherOut[i]) &&
+						(temp = postFinder ? indexOf( seed, elem ) : preMap[i]) > -1 ) {
+
+						seed[temp] = !(results[temp] = elem);
+					}
+				}
+			}
+
+		// Add elements to results, through postFinder if defined
+		} else {
+			matcherOut = condense(
+				matcherOut === results ?
+					matcherOut.splice( preexisting, matcherOut.length ) :
+					matcherOut
+			);
+			if ( postFinder ) {
+				postFinder( null, results, matcherOut, xml );
+			} else {
+				push.apply( results, matcherOut );
+			}
+		}
+	});
+}
+
+function matcherFromTokens( tokens ) {
+	var checkContext, matcher, j,
+		len = tokens.length,
+		leadingRelative = Expr.relative[ tokens[0].type ],
+		implicitRelative = leadingRelative || Expr.relative[" "],
+		i = leadingRelative ? 1 : 0,
+
+		// The foundational matcher ensures that elements are reachable from top-level context(s)
+		matchContext = addCombinator( function( elem ) {
+			return elem === checkContext;
+		}, implicitRelative, true ),
+		matchAnyContext = addCombinator( function( elem ) {
+			return indexOf( checkContext, elem ) > -1;
+		}, implicitRelative, true ),
+		matchers = [ function( elem, context, xml ) {
+			var ret = ( !leadingRelative && ( xml || context !== outermostContext ) ) || (
+				(checkContext = context).nodeType ?
+					matchContext( elem, context, xml ) :
+					matchAnyContext( elem, context, xml ) );
+			// Avoid hanging onto element (issue #299)
+			checkContext = null;
+			return ret;
+		} ];
+
+	for ( ; i < len; i++ ) {
+		if ( (matcher = Expr.relative[ tokens[i].type ]) ) {
+			matchers = [ addCombinator(elementMatcher( matchers ), matcher) ];
+		} else {
+			matcher = Expr.filter[ tokens[i].type ].apply( null, tokens[i].matches );
+
+			// Return special upon seeing a positional matcher
+			if ( matcher[ expando ] ) {
+				// Find the next relative operator (if any) for proper handling
+				j = ++i;
+				for ( ; j < len; j++ ) {
+					if ( Expr.relative[ tokens[j].type ] ) {
+						break;
+					}
+				}
+				return setMatcher(
+					i > 1 && elementMatcher( matchers ),
+					i > 1 && toSelector(
+						// If the preceding token was a descendant combinator, insert an implicit any-element `*`
+						tokens.slice( 0, i - 1 ).concat({ value: tokens[ i - 2 ].type === " " ? "*" : "" })
+					).replace( rtrim, "$1" ),
+					matcher,
+					i < j && matcherFromTokens( tokens.slice( i, j ) ),
+					j < len && matcherFromTokens( (tokens = tokens.slice( j )) ),
+					j < len && toSelector( tokens )
+				);
+			}
+			matchers.push( matcher );
+		}
+	}
+
+	return elementMatcher( matchers );
+}
+
+function matcherFromGroupMatchers( elementMatchers, setMatchers ) {
+	var bySet = setMatchers.length > 0,
+		byElement = elementMatchers.length > 0,
+		superMatcher = function( seed, context, xml, results, outermost ) {
+			var elem, j, matcher,
+				matchedCount = 0,
+				i = "0",
+				unmatched = seed && [],
+				setMatched = [],
+				contextBackup = outermostContext,
+				// We must always have either seed elements or outermost context
+				elems = seed || byElement && Expr.find["TAG"]( "*", outermost ),
+				// Use integer dirruns iff this is the outermost matcher
+				dirrunsUnique = (dirruns += contextBackup == null ? 1 : Math.random() || 0.1),
+				len = elems.length;
+
+			if ( outermost ) {
+				outermostContext = context === document || context || outermost;
+			}
+
+			// Add elements passing elementMatchers directly to results
+			// Support: IE<9, Safari
+			// Tolerate NodeList properties (IE: "length"; Safari: <number>) matching elements by id
+			for ( ; i !== len && (elem = elems[i]) != null; i++ ) {
+				if ( byElement && elem ) {
+					j = 0;
+					if ( !context && elem.ownerDocument !== document ) {
+						setDocument( elem );
+						xml = !documentIsHTML;
+					}
+					while ( (matcher = elementMatchers[j++]) ) {
+						if ( matcher( elem, context || document, xml) ) {
+							results.push( elem );
+							break;
+						}
+					}
+					if ( outermost ) {
+						dirruns = dirrunsUnique;
+					}
+				}
+
+				// Track unmatched elements for set filters
+				if ( bySet ) {
+					// They will have gone through all possible matchers
+					if ( (elem = !matcher && elem) ) {
+						matchedCount--;
+					}
+
+					// Lengthen the array for every element, matched or not
+					if ( seed ) {
+						unmatched.push( elem );
+					}
+				}
+			}
+
+			// `i` is now the count of elements visited above, and adding it to `matchedCount`
+			// makes the latter nonnegative.
+			matchedCount += i;
+
+			// Apply set filters to unmatched elements
+			// NOTE: This can be skipped if there are no unmatched elements (i.e., `matchedCount`
+			// equals `i`), unless we didn't visit _any_ elements in the above loop because we have
+			// no element matchers and no seed.
+			// Incrementing an initially-string "0" `i` allows `i` to remain a string only in that
+			// case, which will result in a "00" `matchedCount` that differs from `i` but is also
+			// numerically zero.
+			if ( bySet && i !== matchedCount ) {
+				j = 0;
+				while ( (matcher = setMatchers[j++]) ) {
+					matcher( unmatched, setMatched, context, xml );
+				}
+
+				if ( seed ) {
+					// Reintegrate element matches to eliminate the need for sorting
+					if ( matchedCount > 0 ) {
+						while ( i-- ) {
+							if ( !(unmatched[i] || setMatched[i]) ) {
+								setMatched[i] = pop.call( results );
+							}
+						}
+					}
+
+					// Discard index placeholder values to get only actual matches
+					setMatched = condense( setMatched );
+				}
+
+				// Add matches to results
+				push.apply( results, setMatched );
+
+				// Seedless set matches succeeding multiple successful matchers stipulate sorting
+				if ( outermost && !seed && setMatched.length > 0 &&
+					( matchedCount + setMatchers.length ) > 1 ) {
+
+					Sizzle.uniqueSort( results );
+				}
+			}
+
+			// Override manipulation of globals by nested matchers
+			if ( outermost ) {
+				dirruns = dirrunsUnique;
+				outermostContext = contextBackup;
+			}
+
+			return unmatched;
+		};
+
+	return bySet ?
+		markFunction( superMatcher ) :
+		superMatcher;
+}
+
+compile = Sizzle.compile = function( selector, match /* Internal Use Only */ ) {
+	var i,
+		setMatchers = [],
+		elementMatchers = [],
+		cached = compilerCache[ selector + " " ];
+
+	if ( !cached ) {
+		// Generate a function of recursive functions that can be used to check each element
+		if ( !match ) {
+			match = tokenize( selector );
+		}
+		i = match.length;
+		while ( i-- ) {
+			cached = matcherFromTokens( match[i] );
+			if ( cached[ expando ] ) {
+				setMatchers.push( cached );
+			} else {
+				elementMatchers.push( cached );
+			}
+		}
+
+		// Cache the compiled function
+		cached = compilerCache( selector, matcherFromGroupMatchers( elementMatchers, setMatchers ) );
+
+		// Save selector and tokenization
+		cached.selector = selector;
+	}
+	return cached;
+};
+
+/**
+ * A low-level selection function that works with Sizzle's compiled
+ *  selector functions
+ * @param {String|Function} selector A selector or a pre-compiled
+ *  selector function built with Sizzle.compile
+ * @param {Element} context
+ * @param {Array} [results]
+ * @param {Array} [seed] A set of elements to match against
+ */
+select = Sizzle.select = function( selector, context, results, seed ) {
+	var i, tokens, token, type, find,
+		compiled = typeof selector === "function" && selector,
+		match = !seed && tokenize( (selector = compiled.selector || selector) );
+
+	results = results || [];
+
+	// Try to minimize operations if there is only one selector in the list and no seed
+	// (the latter of which guarantees us context)
+	if ( match.length === 1 ) {
+
+		// Reduce context if the leading compound selector is an ID
+		tokens = match[0] = match[0].slice( 0 );
+		if ( tokens.length > 2 && (token = tokens[0]).type === "ID" &&
+				support.getById && context.nodeType === 9 && documentIsHTML &&
+				Expr.relative[ tokens[1].type ] ) {
+
+			context = ( Expr.find["ID"]( token.matches[0].replace(runescape, funescape), context ) || [] )[0];
+			if ( !context ) {
+				return results;
+
+			// Precompiled matchers will still verify ancestry, so step up a level
+			} else if ( compiled ) {
+				context = context.parentNode;
+			}
+
+			selector = selector.slice( tokens.shift().value.length );
+		}
+
+		// Fetch a seed set for right-to-left matching
+		i = matchExpr["needsContext"].test( selector ) ? 0 : tokens.length;
+		while ( i-- ) {
+			token = tokens[i];
+
+			// Abort if we hit a combinator
+			if ( Expr.relative[ (type = token.type) ] ) {
+				break;
+			}
+			if ( (find = Expr.find[ type ]) ) {
+				// Search, expanding context for leading sibling combinators
+				if ( (seed = find(
+					token.matches[0].replace( runescape, funescape ),
+					rsibling.test( tokens[0].type ) && testContext( context.parentNode ) || context
+				)) ) {
+
+					// If seed is empty or no tokens remain, we can return early
+					tokens.splice( i, 1 );
+					selector = seed.length && toSelector( tokens );
+					if ( !selector ) {
+						push.apply( results, seed );
+						return results;
+					}
+
+					break;
+				}
+			}
+		}
+	}
+
+	// Compile and execute a filtering function if one is not provided
+	// Provide `match` to avoid retokenization if we modified the selector above
+	( compiled || compile( selector, match ) )(
+		seed,
+		context,
+		!documentIsHTML,
+		results,
+		!context || rsibling.test( selector ) && testContext( context.parentNode ) || context
+	);
+	return results;
+};
+
+// One-time assignments
+
+// Sort stability
+support.sortStable = expando.split("").sort( sortOrder ).join("") === expando;
+
+// Support: Chrome 14-35+
+// Always assume duplicates if they aren't passed to the comparison function
+support.detectDuplicates = !!hasDuplicate;
+
+// Initialize against the default document
+setDocument();
+
+// Support: Webkit<537.32 - Safari 6.0.3/Chrome 25 (fixed in Chrome 27)
+// Detached nodes confoundingly follow *each other*
+support.sortDetached = assert(function( div1 ) {
+	// Should return 1, but returns 4 (following)
+	return div1.compareDocumentPosition( document.createElement("div") ) & 1;
+});
+
+// Support: IE<8
+// Prevent attribute/property "interpolation"
+// http://msdn.microsoft.com/en-us/library/ms536429%28VS.85%29.aspx
+if ( !assert(function( div ) {
+	div.innerHTML = "<a href='#'></a>";
+	return div.firstChild.getAttribute("href") === "#" ;
+}) ) {
+	addHandle( "type|href|height|width", function( elem, name, isXML ) {
+		if ( !isXML ) {
+			return elem.getAttribute( name, name.toLowerCase() === "type" ? 1 : 2 );
+		}
+	});
+}
+
+// Support: IE<9
+// Use defaultValue in place of getAttribute("value")
+if ( !support.attributes || !assert(function( div ) {
+	div.innerHTML = "<input/>";
+	div.firstChild.setAttribute( "value", "" );
+	return div.firstChild.getAttribute( "value" ) === "";
+}) ) {
+	addHandle( "value", function( elem, name, isXML ) {
+		if ( !isXML && elem.nodeName.toLowerCase() === "input" ) {
+			return elem.defaultValue;
+		}
+	});
+}
+
+// Support: IE<9
+// Use getAttributeNode to fetch booleans when getAttribute lies
+if ( !assert(function( div ) {
+	return div.getAttribute("disabled") == null;
+}) ) {
+	addHandle( booleans, function( elem, name, isXML ) {
+		var val;
+		if ( !isXML ) {
+			return elem[ name ] === true ? name.toLowerCase() :
+					(val = elem.getAttributeNode( name )) && val.specified ?
+					val.value :
+				null;
+		}
+	});
+}
+
+return Sizzle;
+
+})( window );
+
+
+
+jQuery.find = Sizzle;
+jQuery.expr = Sizzle.selectors;
+jQuery.expr[ ":" ] = jQuery.expr.pseudos;
+jQuery.uniqueSort = jQuery.unique = Sizzle.uniqueSort;
+jQuery.text = Sizzle.getText;
+jQuery.isXMLDoc = Sizzle.isXML;
+jQuery.contains = Sizzle.contains;
+
+
+
+var dir = function( elem, dir, until ) {
+	var matched = [],
+		truncate = until !== undefined;
+
+	while ( ( elem = elem[ dir ] ) && elem.nodeType !== 9 ) {
+		if ( elem.nodeType === 1 ) {
+			if ( truncate && jQuery( elem ).is( until ) ) {
+				break;
+			}
+			matched.push( elem );
+		}
+	}
+	return matched;
+};
+
+
+var siblings = function( n, elem ) {
+	var matched = [];
+
+	for ( ; n; n = n.nextSibling ) {
+		if ( n.nodeType === 1 && n !== elem ) {
+			matched.push( n );
+		}
+	}
+
+	return matched;
+};
+
+
+var rneedsContext = jQuery.expr.match.needsContext;
+
+var rsingleTag = ( /^<([\w-]+)\s*\/?>(?:<\/\1>|)$/ );
+
+
+
+var risSimple = /^.[^:#\[\.,]*$/;
+
+// Implement the identical functionality for filter and not
+function winnow( elements, qualifier, not ) {
+	if ( jQuery.isFunction( qualifier ) ) {
+		return jQuery.grep( elements, function( elem, i ) {
+			/* jshint -W018 */
+			return !!qualifier.call( elem, i, elem ) !== not;
+		} );
+
+	}
+
+	if ( qualifier.nodeType ) {
+		return jQuery.grep( elements, function( elem ) {
+			return ( elem === qualifier ) !== not;
+		} );
+
+	}
+
+	if ( typeof qualifier === "string" ) {
+		if ( risSimple.test( qualifier ) ) {
+			return jQuery.filter( qualifier, elements, not );
+		}
+
+		qualifier = jQuery.filter( qualifier, elements );
+	}
+
+	return jQuery.grep( elements, function( elem ) {
+		return ( indexOf.call( qualifier, elem ) > -1 ) !== not;
+	} );
+}
+
+jQuery.filter = function( expr, elems, not ) {
+	var elem = elems[ 0 ];
+
+	if ( not ) {
+		expr = ":not(" + expr + ")";
+	}
+
+	return elems.length === 1 && elem.nodeType === 1 ?
+		jQuery.find.matchesSelector( elem, expr ) ? [ elem ] : [] :
+		jQuery.find.matches( expr, jQuery.grep( elems, function( elem ) {
+			return elem.nodeType === 1;
+		} ) );
+};
+
+jQuery.fn.extend( {
+	find: function( selector ) {
+		var i,
+			len = this.length,
+			ret = [],
+			self = this;
+
+		if ( typeof selector !== "string" ) {
+			return this.pushStack( jQuery( selector ).filter( function() {
+				for ( i = 0; i < len; i++ ) {
+					if ( jQuery.contains( self[ i ], this ) ) {
+						return true;
+					}
+				}
+			} ) );
+		}
+
+		for ( i = 0; i < len; i++ ) {
+			jQuery.find( selector, self[ i ], ret );
+		}
+
+		// Needed because $( selector, context ) becomes $( context ).find( selector )
+		ret = this.pushStack( len > 1 ? jQuery.unique( ret ) : ret );
+		ret.selector = this.selector ? this.selector + " " + selector : selector;
+		return ret;
+	},
+	filter: function( selector ) {
+		return this.pushStack( winnow( this, selector || [], false ) );
+	},
+	not: function( selector ) {
+		return this.pushStack( winnow( this, selector || [], true ) );
+	},
+	is: function( selector ) {
+		return !!winnow(
+			this,
+
+			// If this is a positional/relative selector, check membership in the returned set
+			// so $("p:first").is("p:last") won't return true for a doc with two "p".
+			typeof selector === "string" && rneedsContext.test( selector ) ?
+				jQuery( selector ) :
+				selector || [],
+			false
+		).length;
+	}
+} );
+
+
+// Initialize a jQuery object
+
+
+// A central reference to the root jQuery(document)
+var rootjQuery,
+
+	// A simple way to check for HTML strings
+	// Prioritize #id over <tag> to avoid XSS via location.hash (#9521)
+	// Strict HTML recognition (#11290: must start with <)
+	rquickExpr = /^(?:\s*(<[\w\W]+>)[^>]*|#([\w-]*))$/,
+
+	init = jQuery.fn.init = function( selector, context, root ) {
+		var match, elem;
+
+		// HANDLE: $(""), $(null), $(undefined), $(false)
+		if ( !selector ) {
+			return this;
+		}
+
+		// Method init() accepts an alternate rootjQuery
+		// so migrate can support jQuery.sub (gh-2101)
+		root = root || rootjQuery;
+
+		// Handle HTML strings
+		if ( typeof selector === "string" ) {
+			if ( selector[ 0 ] === "<" &&
+				selector[ selector.length - 1 ] === ">" &&
+				selector.length >= 3 ) {
+
+				// Assume that strings that start and end with <> are HTML and skip the regex check
+				match = [ null, selector, null ];
+
+			} else {
+				match = rquickExpr.exec( selector );
+			}
+
+			// Match html or make sure no context is specified for #id
+			if ( match && ( match[ 1 ] || !context ) ) {
+
+				// HANDLE: $(html) -> $(array)
+				if ( match[ 1 ] ) {
+					context = context instanceof jQuery ? context[ 0 ] : context;
+
+					// Option to run scripts is true for back-compat
+					// Intentionally let the error be thrown if parseHTML is not present
+					jQuery.merge( this, jQuery.parseHTML(
+						match[ 1 ],
+						context && context.nodeType ? context.ownerDocument || context : document,
+						true
+					) );
+
+					// HANDLE: $(html, props)
+					if ( rsingleTag.test( match[ 1 ] ) && jQuery.isPlainObject( context ) ) {
+						for ( match in context ) {
+
+							// Properties of context are called as methods if possible
+							if ( jQuery.isFunction( this[ match ] ) ) {
+								this[ match ]( context[ match ] );
+
+							// ...and otherwise set as attributes
+							} else {
+								this.attr( match, context[ match ] );
+							}
+						}
+					}
+
+					return this;
+
+				// HANDLE: $(#id)
+				} else {
+					elem = document.getElementById( match[ 2 ] );
+
+					// Support: Blackberry 4.6
+					// gEBID returns nodes no longer in the document (#6963)
+					if ( elem && elem.parentNode ) {
+
+						// Inject the element directly into the jQuery object
+						this.length = 1;
+						this[ 0 ] = elem;
+					}
+
+					this.context = document;
+					this.selector = selector;
+					return this;
+				}
+
+			// HANDLE: $(expr, $(...))
+			} else if ( !context || context.jquery ) {
+				return ( context || root ).find( selector );
+
+			// HANDLE: $(expr, context)
+			// (which is just equivalent to: $(context).find(expr)
+			} else {
+				return this.constructor( context ).find( selector );
+			}
+
+		// HANDLE: $(DOMElement)
+		} else if ( selector.nodeType ) {
+			this.context = this[ 0 ] = selector;
+			this.length = 1;
+			return this;
+
+		// HANDLE: $(function)
+		// Shortcut for document ready
+		} else if ( jQuery.isFunction( selector ) ) {
+			return root.ready !== undefined ?
+				root.ready( selector ) :
+
+				// Execute immediately if ready is not present
+				selector( jQuery );
+		}
+
+		if ( selector.selector !== undefined ) {
+			this.selector = selector.selector;
+			this.context = selector.context;
+		}
+
+		return jQuery.makeArray( selector, this );
+	};
+
+// Give the init function the jQuery prototype for later instantiation
+init.prototype = jQuery.fn;
+
+// Initialize central reference
+rootjQuery = jQuery( document );
+
+
+var rparentsprev = /^(?:parents|prev(?:Until|All))/,
+
+	// Methods guaranteed to produce a unique set when starting from a unique set
+	guaranteedUnique = {
+		children: true,
+		contents: true,
+		next: true,
+		prev: true
+	};
+
+jQuery.fn.extend( {
+	has: function( target ) {
+		var targets = jQuery( target, this ),
+			l = targets.length;
+
+		return this.filter( function() {
+			var i = 0;
+			for ( ; i < l; i++ ) {
+				if ( jQuery.contains( this, targets[ i ] ) ) {
+					return true;
+				}
+			}
+		} );
+	},
+
+	closest: function( selectors, context ) {
+		var cur,
+			i = 0,
+			l = this.length,
+			matched = [],
+			pos = rneedsContext.test( selectors ) || typeof selectors !== "string" ?
+				jQuery( selectors, context || this.context ) :
+				0;
+
+		for ( ; i < l; i++ ) {
+			for ( cur = this[ i ]; cur && cur !== context; cur = cur.parentNode ) {
+
+				// Always skip document fragments
+				if ( cur.nodeType < 11 && ( pos ?
+					pos.index( cur ) > -1 :
+
+					// Don't pass non-elements to Sizzle
+					cur.nodeType === 1 &&
+						jQuery.find.matchesSelector( cur, selectors ) ) ) {
+
+					matched.push( cur );
+					break;
+				}
+			}
+		}
+
+		return this.pushStack( matched.length > 1 ? jQuery.uniqueSort( matched ) : matched );
+	},
+
+	// Determine the position of an element within the set
+	index: function( elem ) {
+
+		// No argument, return index in parent
+		if ( !elem ) {
+			return ( this[ 0 ] && this[ 0 ].parentNode ) ? this.first().prevAll().length : -1;
+		}
+
+		// Index in selector
+		if ( typeof elem === "string" ) {
+			return indexOf.call( jQuery( elem ), this[ 0 ] );
+		}
+
+		// Locate the position of the desired element
+		return indexOf.call( this,
+
+			// If it receives a jQuery object, the first element is used
+			elem.jquery ? elem[ 0 ] : elem
+		);
+	},
+
+	add: function( selector, context ) {
+		return this.pushStack(
+			jQuery.uniqueSort(
+				jQuery.merge( this.get(), jQuery( selector, context ) )
+			)
+		);
+	},
+
+	addBack: function( selector ) {
+		return this.add( selector == null ?
+			this.prevObject : this.prevObject.filter( selector )
+		);
+	}
+} );
+
+function sibling( cur, dir ) {
+	while ( ( cur = cur[ dir ] ) && cur.nodeType !== 1 ) {}
+	return cur;
+}
+
+jQuery.each( {
+	parent: function( elem ) {
+		var parent = elem.parentNode;
+		return parent && parent.nodeType !== 11 ? parent : null;
+	},
+	parents: function( elem ) {
+		return dir( elem, "parentNode" );
+	},
+	parentsUntil: function( elem, i, until ) {
+		return dir( elem, "parentNode", until );
+	},
+	next: function( elem ) {
+		return sibling( elem, "nextSibling" );
+	},
+	prev: function( elem ) {
+		return sibling( elem, "previousSibling" );
+	},
+	nextAll: function( elem ) {
+		return dir( elem, "nextSibling" );
+	},
+	prevAll: function( elem ) {
+		return dir( elem, "previousSibling" );
+	},
+	nextUntil: function( elem, i, until ) {
+		return dir( elem, "nextSibling", until );
+	},
+	prevUntil: function( elem, i, until ) {
+		return dir( elem, "previousSibling", until );
+	},
+	siblings: function( elem ) {
+		return siblings( ( elem.parentNode || {} ).firstChild, elem );
+	},
+	children: function( elem ) {
+		return siblings( elem.firstChild );
+	},
+	contents: function( elem ) {
+		return elem.contentDocument || jQuery.merge( [], elem.childNodes );
+	}
+}, function( name, fn ) {
+	jQuery.fn[ name ] = function( until, selector ) {
+		var matched = jQuery.map( this, fn, until );
+
+		if ( name.slice( -5 ) !== "Until" ) {
+			selector = until;
+		}
+
+		if ( selector && typeof selector === "string" ) {
+			matched = jQuery.filter( selector, matched );
+		}
+
+		if ( this.length > 1 ) {
+
+			// Remove duplicates
+			if ( !guaranteedUnique[ name ] ) {
+				jQuery.uniqueSort( matched );
+			}
+
+			// Reverse order for parents* and prev-derivatives
+			if ( rparentsprev.test( name ) ) {
+				matched.reverse();
+			}
+		}
+
+		return this.pushStack( matched );
+	};
+} );
+var rnotwhite = ( /\S+/g );
+
+
+
+// Convert String-formatted options into Object-formatted ones
+function createOptions( options ) {
+	var object = {};
+	jQuery.each( options.match( rnotwhite ) || [], function( _, flag ) {
+		object[ flag ] = true;
+	} );
+	return object;
+}
+
+/*
+ * Create a callback list using the following parameters:
+ *
+ *	options: an optional list of space-separated options that will change how
+ *			the callback list behaves or a more traditional option object
+ *
+ * By default a callback list will act like an event callback list and can be
+ * "fired" multiple times.
+ *
+ * Possible options:
+ *
+ *	once:			will ensure the callback list can only be fired once (like a Deferred)
+ *
+ *	memory:			will keep track of previous values and will call any callback added
+ *					after the list has been fired right away with the latest "memorized"
+ *					values (like a Deferred)
+ *
+ *	unique:			will ensure a callback can only be added once (no duplicate in the list)
+ *
+ *	stopOnFalse:	interrupt callings when a callback returns false
+ *
+ */
+jQuery.Callbacks = function( options ) {
+
+	// Convert options from String-formatted to Object-formatted if needed
+	// (we check in cache first)
+	options = typeof options === "string" ?
+		createOptions( options ) :
+		jQuery.extend( {}, options );
+
+	var // Flag to know if list is currently firing
+		firing,
+
+		// Last fire value for non-forgettable lists
+		memory,
+
+		// Flag to know if list was already fired
+		fired,
+
+		// Flag to prevent firing
+		locked,
+
+		// Actual callback list
+		list = [],
+
+		// Queue of execution data for repeatable lists
+		queue = [],
+
+		// Index of currently firing callback (modified by add/remove as needed)
+		firingIndex = -1,
+
+		// Fire callbacks
+		fire = function() {
+
+			// Enforce single-firing
+			locked = options.once;
+
+			// Execute callbacks for all pending executions,
+			// respecting firingIndex overrides and runtime changes
+			fired = firing = true;
+			for ( ; queue.length; firingIndex = -1 ) {
+				memory = queue.shift();
+				while ( ++firingIndex < list.length ) {
+
+					// Run callback and check for early termination
+					if ( list[ firingIndex ].apply( memory[ 0 ], memory[ 1 ] ) === false &&
+						options.stopOnFalse ) {
+
+						// Jump to end and forget the data so .add doesn't re-fire
+						firingIndex = list.length;
+						memory = false;
+					}
+				}
+			}
+
+			// Forget the data if we're done with it
+			if ( !options.memory ) {
+				memory = false;
+			}
+
+			firing = false;
+
+			// Clean up if we're done firing for good
+			if ( locked ) {
+
+				// Keep an empty list if we have data for future add calls
+				if ( memory ) {
+					list = [];
+
+				// Otherwise, this object is spent
+				} else {
+					list = "";
+				}
+			}
+		},
+
+		// Actual Callbacks object
+		self = {
+
+			// Add a callback or a collection of callbacks to the list
+			add: function() {
+				if ( list ) {
+
+					// If we have memory from a past run, we should fire after adding
+					if ( memory && !firing ) {
+						firingIndex = list.length - 1;
+						queue.push( memory );
+					}
+
+					( function add( args ) {
+						jQuery.each( args, function( _, arg ) {
+							if ( jQuery.isFunction( arg ) ) {
+								if ( !options.unique || !self.has( arg ) ) {
+									list.push( arg );
+								}
+							} else if ( arg && arg.length && jQuery.type( arg ) !== "string" ) {
+
+								// Inspect recursively
+								add( arg );
+							}
+						} );
+					} )( arguments );
+
+					if ( memory && !firing ) {
+						fire();
+					}
+				}
+				return this;
+			},
+
+			// Remove a callback from the list
+			remove: function() {
+				jQuery.each( arguments, function( _, arg ) {
+					var index;
+					while ( ( index = jQuery.inArray( arg, list, index ) ) > -1 ) {
+						list.splice( index, 1 );
+
+						// Handle firing indexes
+						if ( index <= firingIndex ) {
+							firingIndex--;
+						}
+					}
+				} );
+				return this;
+			},
+
+			// Check if a given callback is in the list.
+			// If no argument is given, return whether or not list has callbacks attached.
+			has: function( fn ) {
+				return fn ?
+					jQuery.inArray( fn, list ) > -1 :
+					list.length > 0;
+			},
+
+			// Remove all callbacks from the list
+			empty: function() {
+				if ( list ) {
+					list = [];
+				}
+				return this;
+			},
+
+			// Disable .fire and .add
+			// Abort any current/pending executions
+			// Clear all callbacks and values
+			disable: function() {
+				locked = queue = [];
+				list = memory = "";
+				return this;
+			},
+			disabled: function() {
+				return !list;
+			},
+
+			// Disable .fire
+			// Also disable .add unless we have memory (since it would have no effect)
+			// Abort any pending executions
+			lock: function() {
+				locked = queue = [];
+				if ( !memory ) {
+					list = memory = "";
+				}
+				return this;
+			},
+			locked: function() {
+				return !!locked;
+			},
+
+			// Call all callbacks with the given context and arguments
+			fireWith: function( context, args ) {
+				if ( !locked ) {
+					args = args || [];
+					args = [ context, args.slice ? args.slice() : args ];
+					queue.push( args );
+					if ( !firing ) {
+						fire();
+					}
+				}
+				return this;
+			},
+
+			// Call all the callbacks with the given arguments
+			fire: function() {
+				self.fireWith( this, arguments );
+				return this;
+			},
+
+			// To know if the callbacks have already been called at least once
+			fired: function() {
+				return !!fired;
+			}
+		};
+
+	return self;
+};
+
+
+jQuery.extend( {
+
+	Deferred: function( func ) {
+		var tuples = [
+
+				// action, add listener, listener list, final state
+				[ "resolve", "done", jQuery.Callbacks( "once memory" ), "resolved" ],
+				[ "reject", "fail", jQuery.Callbacks( "once memory" ), "rejected" ],
+				[ "notify", "progress", jQuery.Callbacks( "memory" ) ]
+			],
+			state = "pending",
+			promise = {
+				state: function() {
+					return state;
+				},
+				always: function() {
+					deferred.done( arguments ).fail( arguments );
+					return this;
+				},
+				then: function( /* fnDone, fnFail, fnProgress */ ) {
+					var fns = arguments;
+					return jQuery.Deferred( function( newDefer ) {
+						jQuery.each( tuples, function( i, tuple ) {
+							var fn = jQuery.isFunction( fns[ i ] ) && fns[ i ];
+
+							// deferred[ done | fail | progress ] for forwarding actions to newDefer
+							deferred[ tuple[ 1 ] ]( function() {
+								var returned = fn && fn.apply( this, arguments );
+								if ( returned && jQuery.isFunction( returned.promise ) ) {
+									returned.promise()
+										.progress( newDefer.notify )
+										.done( newDefer.resolve )
+										.fail( newDefer.reject );
+								} else {
+									newDefer[ tuple[ 0 ] + "With" ](
+										this === promise ? newDefer.promise() : this,
+										fn ? [ returned ] : arguments
+									);
+								}
+							} );
+						} );
+						fns = null;
+					} ).promise();
+				},
+
+				// Get a promise for this deferred
+				// If obj is provided, the promise aspect is added to the object
+				promise: function( obj ) {
+					return obj != null ? jQuery.extend( obj, promise ) : promise;
+				}
+			},
+			deferred = {};
+
+		// Keep pipe for back-compat
+		promise.pipe = promise.then;
+
+		// Add list-specific methods
+		jQuery.each( tuples, function( i, tuple ) {
+			var list = tuple[ 2 ],
+				stateString = tuple[ 3 ];
+
+			// promise[ done | fail | progress ] = list.add
+			promise[ tuple[ 1 ] ] = list.add;
+
+			// Handle state
+			if ( stateString ) {
+				list.add( function() {
+
+					// state = [ resolved | rejected ]
+					state = stateString;
+
+				// [ reject_list | resolve_list ].disable; progress_list.lock
+				}, tuples[ i ^ 1 ][ 2 ].disable, tuples[ 2 ][ 2 ].lock );
+			}
+
+			// deferred[ resolve | reject | notify ]
+			deferred[ tuple[ 0 ] ] = function() {
+				deferred[ tuple[ 0 ] + "With" ]( this === deferred ? promise : this, arguments );
+				return this;
+			};
+			deferred[ tuple[ 0 ] + "With" ] = list.fireWith;
+		} );
+
+		// Make the deferred a promise
+		promise.promise( deferred );
+
+		// Call given func if any
+		if ( func ) {
+			func.call( deferred, deferred );
+		}
+
+		// All done!
+		return deferred;
+	},
+
+	// Deferred helper
+	when: function( subordinate /* , ..., subordinateN */ ) {
+		var i = 0,
+			resolveValues = slice.call( arguments ),
+			length = resolveValues.length,
+
+			// the count of uncompleted subordinates
+			remaining = length !== 1 ||
+				( subordinate && jQuery.isFunction( subordinate.promise ) ) ? length : 0,
+
+			// the master Deferred.
+			// If resolveValues consist of only a single Deferred, just use that.
+			deferred = remaining === 1 ? subordinate : jQuery.Deferred(),
+
+			// Update function for both resolve and progress values
+			updateFunc = function( i, contexts, values ) {
+				return function( value ) {
+					contexts[ i ] = this;
+					values[ i ] = arguments.length > 1 ? slice.call( arguments ) : value;
+					if ( values === progressValues ) {
+						deferred.notifyWith( contexts, values );
+					} else if ( !( --remaining ) ) {
+						deferred.resolveWith( contexts, values );
+					}
+				};
+			},
+
+			progressValues, progressContexts, resolveContexts;
+
+		// Add listeners to Deferred subordinates; treat others as resolved
+		if ( length > 1 ) {
+			progressValues = new Array( length );
+			progressContexts = new Array( length );
+			resolveContexts = new Array( length );
+			for ( ; i < length; i++ ) {
+				if ( resolveValues[ i ] && jQuery.isFunction( resolveValues[ i ].promise ) ) {
+					resolveValues[ i ].promise()
+						.progress( updateFunc( i, progressContexts, progressValues ) )
+						.done( updateFunc( i, resolveContexts, resolveValues ) )
+						.fail( deferred.reject );
+				} else {
+					--remaining;
+				}
+			}
+		}
+
+		// If we're not waiting on anything, resolve the master
+		if ( !remaining ) {
+			deferred.resolveWith( resolveContexts, resolveValues );
+		}
+
+		return deferred.promise();
+	}
+} );
+
+
+// The deferred used on DOM ready
+var readyList;
+
+jQuery.fn.ready = function( fn ) {
+
+	// Add the callback
+	jQuery.ready.promise().done( fn );
+
+	return this;
+};
+
+jQuery.extend( {
+
+	// Is the DOM ready to be used? Set to true once it occurs.
+	isReady: false,
+
+	// A counter to track how many items to wait for before
+	// the ready event fires. See #6781
+	readyWait: 1,
+
+	// Hold (or release) the ready event
+	holdReady: function( hold ) {
+		if ( hold ) {
+			jQuery.readyWait++;
+		} else {
+			jQuery.ready( true );
+		}
+	},
+
+	// Handle when the DOM is ready
+	ready: function( wait ) {
+
+		// Abort if there are pending holds or we're already ready
+		if ( wait === true ? --jQuery.readyWait : jQuery.isReady ) {
+			return;
+		}
+
+		// Remember that the DOM is ready
+		jQuery.isReady = true;
+
+		// If a normal DOM Ready event fired, decrement, and wait if need be
+		if ( wait !== true && --jQuery.readyWait > 0 ) {
+			return;
+		}
+
+		// If there are functions bound, to execute
+		readyList.resolveWith( document, [ jQuery ] );
+
+		// Trigger any bound ready events
+		if ( jQuery.fn.triggerHandler ) {
+			jQuery( document ).triggerHandler( "ready" );
+			jQuery( document ).off( "ready" );
+		}
+	}
+} );
+
+/**
+ * The ready event handler and self cleanup method
+ */
+function completed() {
+	document.removeEventListener( "DOMContentLoaded", completed );
+	window.removeEventListener( "load", completed );
+	jQuery.ready();
+}
+
+jQuery.ready.promise = function( obj ) {
+	if ( !readyList ) {
+
+		readyList = jQuery.Deferred();
+
+		// Catch cases where $(document).ready() is called
+		// after the browser event has already occurred.
+		// Support: IE9-10 only
+		// Older IE sometimes signals "interactive" too soon
+		if ( document.readyState === "complete" ||
+			( document.readyState !== "loading" && !document.documentElement.doScroll ) ) {
+
+			// Handle it asynchronously to allow scripts the opportunity to delay ready
+			window.setTimeout( jQuery.ready );
+
+		} else {
+
+			// Use the handy event callback
+			document.addEventListener( "DOMContentLoaded", completed );
+
+			// A fallback to window.onload, that will always work
+			window.addEventListener( "load", completed );
+		}
+	}
+	return readyList.promise( obj );
+};
+
+// Kick off the DOM ready check even if the user does not
+jQuery.ready.promise();
+
+
+
+
+// Multifunctional method to get and set values of a collection
+// The value/s can optionally be executed if it's a function
+var access = function( elems, fn, key, value, chainable, emptyGet, raw ) {
+	var i = 0,
+		len = elems.length,
+		bulk = key == null;
+
+	// Sets many values
+	if ( jQuery.type( key ) === "object" ) {
+		chainable = true;
+		for ( i in key ) {
+			access( elems, fn, i, key[ i ], true, emptyGet, raw );
+		}
+
+	// Sets one value
+	} else if ( value !== undefined ) {
+		chainable = true;
+
+		if ( !jQuery.isFunction( value ) ) {
+			raw = true;
+		}
+
+		if ( bulk ) {
+
+			// Bulk operations run against the entire set
+			if ( raw ) {
+				fn.call( elems, value );
+				fn = null;
+
+			// ...except when executing function values
+			} else {
+				bulk = fn;
+				fn = function( elem, key, value ) {
+					return bulk.call( jQuery( elem ), value );
+				};
+			}
+		}
+
+		if ( fn ) {
+			for ( ; i < len; i++ ) {
+				fn(
+					elems[ i ], key, raw ?
+					value :
+					value.call( elems[ i ], i, fn( elems[ i ], key ) )
+				);
+			}
+		}
+	}
+
+	return chainable ?
+		elems :
+
+		// Gets
+		bulk ?
+			fn.call( elems ) :
+			len ? fn( elems[ 0 ], key ) : emptyGet;
+};
+var acceptData = function( owner ) {
+
+	// Accepts only:
+	//  - Node
+	//    - Node.ELEMENT_NODE
+	//    - Node.DOCUMENT_NODE
+	//  - Object
+	//    - Any
+	/* jshint -W018 */
+	return owner.nodeType === 1 || owner.nodeType === 9 || !( +owner.nodeType );
+};
+
+
+
+
+function Data() {
+	this.expando = jQuery.expando + Data.uid++;
+}
+
+Data.uid = 1;
+
+Data.prototype = {
+
+	register: function( owner, initial ) {
+		var value = initial || {};
+
+		// If it is a node unlikely to be stringify-ed or looped over
+		// use plain assignment
+		if ( owner.nodeType ) {
+			owner[ this.expando ] = value;
+
+		// Otherwise secure it in a non-enumerable, non-writable property
+		// configurability must be true to allow the property to be
+		// deleted with the delete operator
+		} else {
+			Object.defineProperty( owner, this.expando, {
+				value: value,
+				writable: true,
+				configurable: true
+			} );
+		}
+		return owner[ this.expando ];
+	},
+	cache: function( owner ) {
+
+		// We can accept data for non-element nodes in modern browsers,
+		// but we should not, see #8335.
+		// Always return an empty object.
+		if ( !acceptData( owner ) ) {
+			return {};
+		}
+
+		// Check if the owner object already has a cache
+		var value = owner[ this.expando ];
+
+		// If not, create one
+		if ( !value ) {
+			value = {};
+
+			// We can accept data for non-element nodes in modern browsers,
+			// but we should not, see #8335.
+			// Always return an empty object.
+			if ( acceptData( owner ) ) {
+
+				// If it is a node unlikely to be stringify-ed or looped over
+				// use plain assignment
+				if ( owner.nodeType ) {
+					owner[ this.expando ] = value;
+
+				// Otherwise secure it in a non-enumerable property
+				// configurable must be true to allow the property to be
+				// deleted when data is removed
+				} else {
+					Object.defineProperty( owner, this.expando, {
+						value: value,
+						configurable: true
+					} );
+				}
+			}
+		}
+
+		return value;
+	},
+	set: function( owner, data, value ) {
+		var prop,
+			cache = this.cache( owner );
+
+		// Handle: [ owner, key, value ] args
+		if ( typeof data === "string" ) {
+			cache[ data ] = value;
+
+		// Handle: [ owner, { properties } ] args
+		} else {
+
+			// Copy the properties one-by-one to the cache object
+			for ( prop in data ) {
+				cache[ prop ] = data[ prop ];
+			}
+		}
+		return cache;
+	},
+	get: function( owner, key ) {
+		return key === undefined ?
+			this.cache( owner ) :
+			owner[ this.expando ] && owner[ this.expando ][ key ];
+	},
+	access: function( owner, key, value ) {
+		var stored;
+
+		// In cases where either:
+		//
+		//   1. No key was specified
+		//   2. A string key was specified, but no value provided
+		//
+		// Take the "read" path and allow the get method to determine
+		// which value to return, respectively either:
+		//
+		//   1. The entire cache object
+		//   2. The data stored at the key
+		//
+		if ( key === undefined ||
+				( ( key && typeof key === "string" ) && value === undefined ) ) {
+
+			stored = this.get( owner, key );
+
+			return stored !== undefined ?
+				stored : this.get( owner, jQuery.camelCase( key ) );
+		}
+
+		// When the key is not a string, or both a key and value
+		// are specified, set or extend (existing objects) with either:
+		//
+		//   1. An object of properties
+		//   2. A key and value
+		//
+		this.set( owner, key, value );
+
+		// Since the "set" path can have two possible entry points
+		// return the expected data based on which path was taken[*]
+		return value !== undefined ? value : key;
+	},
+	remove: function( owner, key ) {
+		var i, name, camel,
+			cache = owner[ this.expando ];
+
+		if ( cache === undefined ) {
+			return;
+		}
+
+		if ( key === undefined ) {
+			this.register( owner );
+
+		} else {
+
+			// Support array or space separated string of keys
+			if ( jQuery.isArray( key ) ) {
+
+				// If "name" is an array of keys...
+				// When data is initially created, via ("key", "val") signature,
+				// keys will be converted to camelCase.
+				// Since there is no way to tell _how_ a key was added, remove
+				// both plain key and camelCase key. #12786
+				// This will only penalize the array argument path.
+				name = key.concat( key.map( jQuery.camelCase ) );
+			} else {
+				camel = jQuery.camelCase( key );
+
+				// Try the string as a key before any manipulation
+				if ( key in cache ) {
+					name = [ key, camel ];
+				} else {
+
+					// If a key with the spaces exists, use it.
+					// Otherwise, create an array by matching non-whitespace
+					name = camel;
+					name = name in cache ?
+						[ name ] : ( name.match( rnotwhite ) || [] );
+				}
+			}
+
+			i = name.length;
+
+			while ( i-- ) {
+				delete cache[ name[ i ] ];
+			}
+		}
+
+		// Remove the expando if there's no more data
+		if ( key === undefined || jQuery.isEmptyObject( cache ) ) {
+
+			// Support: Chrome <= 35-45+
+			// Webkit & Blink performance suffers when deleting properties
+			// from DOM nodes, so set to undefined instead
+			// https://code.google.com/p/chromium/issues/detail?id=378607
+			if ( owner.nodeType ) {
+				owner[ this.expando ] = undefined;
+			} else {
+				delete owner[ this.expando ];
+			}
+		}
+	},
+	hasData: function( owner ) {
+		var cache = owner[ this.expando ];
+		return cache !== undefined && !jQuery.isEmptyObject( cache );
+	}
+};
+var dataPriv = new Data();
+
+var dataUser = new Data();
+
+
+
+//	Implementation Summary
+//
+//	1. Enforce API surface and semantic compatibility with 1.9.x branch
+//	2. Improve the module's maintainability by reducing the storage
+//		paths to a single mechanism.
+//	3. Use the same single mechanism to support "private" and "user" data.
+//	4. _Never_ expose "private" data to user code (TODO: Drop _data, _removeData)
+//	5. Avoid exposing implementation details on user objects (eg. expando properties)
+//	6. Provide a clear path for implementation upgrade to WeakMap in 2014
+
+var rbrace = /^(?:\{[\w\W]*\}|\[[\w\W]*\])$/,
+	rmultiDash = /[A-Z]/g;
+
+function dataAttr( elem, key, data ) {
+	var name;
+
+	// If nothing was found internally, try to fetch any
+	// data from the HTML5 data-* attribute
+	if ( data === undefined && elem.nodeType === 1 ) {
+		name = "data-" + key.replace( rmultiDash, "-$&" ).toLowerCase();
+		data = elem.getAttribute( name );
+
+		if ( typeof data === "string" ) {
+			try {
+				data = data === "true" ? true :
+					data === "false" ? false :
+					data === "null" ? null :
+
+					// Only convert to a number if it doesn't change the string
+					+data + "" === data ? +data :
+					rbrace.test( data ) ? jQuery.parseJSON( data ) :
+					data;
+			} catch ( e ) {}
+
+			// Make sure we set the data so it isn't changed later
+			dataUser.set( elem, key, data );
+		} else {
+			data = undefined;
+		}
+	}
+	return data;
+}
+
+jQuery.extend( {
+	hasData: function( elem ) {
+		return dataUser.hasData( elem ) || dataPriv.hasData( elem );
+	},
+
+	data: function( elem, name, data ) {
+		return dataUser.access( elem, name, data );
+	},
+
+	removeData: function( elem, name ) {
+		dataUser.remove( elem, name );
+	},
+
+	// TODO: Now that all calls to _data and _removeData have been replaced
+	// with direct calls to dataPriv methods, these can be deprecated.
+	_data: function( elem, name, data ) {
+		return dataPriv.access( elem, name, data );
+	},
+
+	_removeData: function( elem, name ) {
+		dataPriv.remove( elem, name );
+	}
+} );
+
+jQuery.fn.extend( {
+	data: function( key, value ) {
+		var i, name, data,
+			elem = this[ 0 ],
+			attrs = elem && elem.attributes;
+
+		// Gets all values
+		if ( key === undefined ) {
+			if ( this.length ) {
+				data = dataUser.get( elem );
+
+				if ( elem.nodeType === 1 && !dataPriv.get( elem, "hasDataAttrs" ) ) {
+					i = attrs.length;
+					while ( i-- ) {
+
+						// Support: IE11+
+						// The attrs elements can be null (#14894)
+						if ( attrs[ i ] ) {
+							name = attrs[ i ].name;
+							if ( name.indexOf( "data-" ) === 0 ) {
+								name = jQuery.camelCase( name.slice( 5 ) );
+								dataAttr( elem, name, data[ name ] );
+							}
+						}
+					}
+					dataPriv.set( elem, "hasDataAttrs", true );
+				}
+			}
+
+			return data;
+		}
+
+		// Sets multiple values
+		if ( typeof key === "object" ) {
+			return this.each( function() {
+				dataUser.set( this, key );
+			} );
+		}
+
+		return access( this, function( value ) {
+			var data, camelKey;
+
+			// The calling jQuery object (element matches) is not empty
+			// (and therefore has an element appears at this[ 0 ]) and the
+			// `value` parameter was not undefined. An empty jQuery object
+			// will result in `undefined` for elem = this[ 0 ] which will
+			// throw an exception if an attempt to read a data cache is made.
+			if ( elem && value === undefined ) {
+
+				// Attempt to get data from the cache
+				// with the key as-is
+				data = dataUser.get( elem, key ) ||
+
+					// Try to find dashed key if it exists (gh-2779)
+					// This is for 2.2.x only
+					dataUser.get( elem, key.replace( rmultiDash, "-$&" ).toLowerCase() );
+
+				if ( data !== undefined ) {
+					return data;
+				}
+
+				camelKey = jQuery.camelCase( key );
+
+				// Attempt to get data from the cache
+				// with the key camelized
+				data = dataUser.get( elem, camelKey );
+				if ( data !== undefined ) {
+					return data;
+				}
+
+				// Attempt to "discover" the data in
+				// HTML5 custom data-* attrs
+				data = dataAttr( elem, camelKey, undefined );
+				if ( data !== undefined ) {
+					return data;
+				}
+
+				// We tried really hard, but the data doesn't exist.
+				return;
+			}
+
+			// Set the data...
+			camelKey = jQuery.camelCase( key );
+			this.each( function() {
+
+				// First, attempt to store a copy or reference of any
+				// data that might've been store with a camelCased key.
+				var data = dataUser.get( this, camelKey );
+
+				// For HTML5 data-* attribute interop, we have to
+				// store property names with dashes in a camelCase form.
+				// This might not apply to all properties...*
+				dataUser.set( this, camelKey, value );
+
+				// *... In the case of properties that might _actually_
+				// have dashes, we need to also store a copy of that
+				// unchanged property.
+				if ( key.indexOf( "-" ) > -1 && data !== undefined ) {
+					dataUser.set( this, key, value );
+				}
+			} );
+		}, null, value, arguments.length > 1, null, true );
+	},
+
+	removeData: function( key ) {
+		return this.each( function() {
+			dataUser.remove( this, key );
+		} );
+	}
+} );
+
+
+jQuery.extend( {
+	queue: function( elem, type, data ) {
+		var queue;
+
+		if ( elem ) {
+			type = ( type || "fx" ) + "queue";
+			queue = dataPriv.get( elem, type );
+
+			// Speed up dequeue by getting out quickly if this is just a lookup
+			if ( data ) {
+				if ( !queue || jQuery.isArray( data ) ) {
+					queue = dataPriv.access( elem, type, jQuery.makeArray( data ) );
+				} else {
+					queue.push( data );
+				}
+			}
+			return queue || [];
+		}
+	},
+
+	dequeue: function( elem, type ) {
+		type = type || "fx";
+
+		var queue = jQuery.queue( elem, type ),
+			startLength = queue.length,
+			fn = queue.shift(),
+			hooks = jQuery._queueHooks( elem, type ),
+			next = function() {
+				jQuery.dequeue( elem, type );
+			};
+
+		// If the fx queue is dequeued, always remove the progress sentinel
+		if ( fn === "inprogress" ) {
+			fn = queue.shift();
+			startLength--;
+		}
+
+		if ( fn ) {
+
+			// Add a progress sentinel to prevent the fx queue from being
+			// automatically dequeued
+			if ( type === "fx" ) {
+				queue.unshift( "inprogress" );
+			}
+
+			// Clear up the last queue stop function
+			delete hooks.stop;
+			fn.call( elem, next, hooks );
+		}
+
+		if ( !startLength && hooks ) {
+			hooks.empty.fire();
+		}
+	},
+
+	// Not public - generate a queueHooks object, or return the current one
+	_queueHooks: function( elem, type ) {
+		var key = type + "queueHooks";
+		return dataPriv.get( elem, key ) || dataPriv.access( elem, key, {
+			empty: jQuery.Callbacks( "once memory" ).add( function() {
+				dataPriv.remove( elem, [ type + "queue", key ] );
+			} )
+		} );
+	}
+} );
+
+jQuery.fn.extend( {
+	queue: function( type, data ) {
+		var setter = 2;
+
+		if ( typeof type !== "string" ) {
+			data = type;
+			type = "fx";
+			setter--;
+		}
+
+		if ( arguments.length < setter ) {
+			return jQuery.queue( this[ 0 ], type );
+		}
+
+		return data === undefined ?
+			this :
+			this.each( function() {
+				var queue = jQuery.queue( this, type, data );
+
+				// Ensure a hooks for this queue
+				jQuery._queueHooks( this, type );
+
+				if ( type === "fx" && queue[ 0 ] !== "inprogress" ) {
+					jQuery.dequeue( this, type );
+				}
+			} );
+	},
+	dequeue: function( type ) {
+		return this.each( function() {
+			jQuery.dequeue( this, type );
+		} );
+	},
+	clearQueue: function( type ) {
+		return this.queue( type || "fx", [] );
+	},
+
+	// Get a promise resolved when queues of a certain type
+	// are emptied (fx is the type by default)
+	promise: function( type, obj ) {
+		var tmp,
+			count = 1,
+			defer = jQuery.Deferred(),
+			elements = this,
+			i = this.length,
+			resolve = function() {
+				if ( !( --count ) ) {
+					defer.resolveWith( elements, [ elements ] );
+				}
+			};
+
+		if ( typeof type !== "string" ) {
+			obj = type;
+			type = undefined;
+		}
+		type = type || "fx";
+
+		while ( i-- ) {
+			tmp = dataPriv.get( elements[ i ], type + "queueHooks" );
+			if ( tmp && tmp.empty ) {
+				count++;
+				tmp.empty.add( resolve );
+			}
+		}
+		resolve();
+		return defer.promise( obj );
+	}
+} );
+var pnum = ( /[+-]?(?:\d*\.|)\d+(?:[eE][+-]?\d+|)/ ).source;
+
+var rcssNum = new RegExp( "^(?:([+-])=|)(" + pnum + ")([a-z%]*)$", "i" );
+
+
+var cssExpand = [ "Top", "Right", "Bottom", "Left" ];
+
+var isHidden = function( elem, el ) {
+
+		// isHidden might be called from jQuery#filter function;
+		// in that case, element will be second argument
+		elem = el || elem;
+		return jQuery.css( elem, "display" ) === "none" ||
+			!jQuery.contains( elem.ownerDocument, elem );
+	};
+
+
+
+function adjustCSS( elem, prop, valueParts, tween ) {
+	var adjusted,
+		scale = 1,
+		maxIterations = 20,
+		currentValue = tween ?
+			function() { return tween.cur(); } :
+			function() { return jQuery.css( elem, prop, "" ); },
+		initial = currentValue(),
+		unit = valueParts && valueParts[ 3 ] || ( jQuery.cssNumber[ prop ] ? "" : "px" ),
+
+		// Starting value computation is required for potential unit mismatches
+		initialInUnit = ( jQuery.cssNumber[ prop ] || unit !== "px" && +initial ) &&
+			rcssNum.exec( jQuery.css( elem, prop ) );
+
+	if ( initialInUnit && initialInUnit[ 3 ] !== unit ) {
+
+		// Trust units reported by jQuery.css
+		unit = unit || initialInUnit[ 3 ];
+
+		// Make sure we update the tween properties later on
+		valueParts = valueParts || [];
+
+		// Iteratively approximate from a nonzero starting point
+		initialInUnit = +initial || 1;
+
+		do {
+
+			// If previous iteration zeroed out, double until we get *something*.
+			// Use string for doubling so we don't accidentally see scale as unchanged below
+			scale = scale || ".5";
+
+			// Adjust and apply
+			initialInUnit = initialInUnit / scale;
+			jQuery.style( elem, prop, initialInUnit + unit );
+
+		// Update scale, tolerating zero or NaN from tween.cur()
+		// Break the loop if scale is unchanged or perfect, or if we've just had enough.
+		} while (
+			scale !== ( scale = currentValue() / initial ) && scale !== 1 && --maxIterations
+		);
+	}
+
+	if ( valueParts ) {
+		initialInUnit = +initialInUnit || +initial || 0;
+
+		// Apply relative offset (+=/-=) if specified
+		adjusted = valueParts[ 1 ] ?
+			initialInUnit + ( valueParts[ 1 ] + 1 ) * valueParts[ 2 ] :
+			+valueParts[ 2 ];
+		if ( tween ) {
+			tween.unit = unit;
+			tween.start = initialInUnit;
+			tween.end = adjusted;
+		}
+	}
+	return adjusted;
+}
+var rcheckableType = ( /^(?:checkbox|radio)$/i );
+
+var rtagName = ( /<([\w:-]+)/ );
+
+var rscriptType = ( /^$|\/(?:java|ecma)script/i );
+
+
+
+// We have to close these tags to support XHTML (#13200)
+var wrapMap = {
+
+	// Support: IE9
+	option: [ 1, "<select multiple='multiple'>", "</select>" ],
+
+	// XHTML parsers do not magically insert elements in the
+	// same way that tag soup parsers do. So we cannot shorten
+	// this by omitting <tbody> or other required elements.
+	thead: [ 1, "<table>", "</table>" ],
+	col: [ 2, "<table><colgroup>", "</colgroup></table>" ],
+	tr: [ 2, "<table><tbody>", "</tbody></table>" ],
+	td: [ 3, "<table><tbody><tr>", "</tr></tbody></table>" ],
+
+	_default: [ 0, "", "" ]
+};
+
+// Support: IE9
+wrapMap.optgroup = wrapMap.option;
+
+wrapMap.tbody = wrapMap.tfoot = wrapMap.colgroup = wrapMap.caption = wrapMap.thead;
+wrapMap.th = wrapMap.td;
+
+
+function getAll( context, tag ) {
+
+	// Support: IE9-11+
+	// Use typeof to avoid zero-argument method invocation on host objects (#15151)
+	var ret = typeof context.getElementsByTagName !== "undefined" ?
+			context.getElementsByTagName( tag || "*" ) :
+			typeof context.querySelectorAll !== "undefined" ?
+				context.querySelectorAll( tag || "*" ) :
+			[];
+
+	return tag === undefined || tag && jQuery.nodeName( context, tag ) ?
+		jQuery.merge( [ context ], ret ) :
+		ret;
+}
+
+
+// Mark scripts as having already been evaluated
+function setGlobalEval( elems, refElements ) {
+	var i = 0,
+		l = elems.length;
+
+	for ( ; i < l; i++ ) {
+		dataPriv.set(
+			elems[ i ],
+			"globalEval",
+			!refElements || dataPriv.get( refElements[ i ], "globalEval" )
+		);
+	}
+}
+
+
+var rhtml = /<|&#?\w+;/;
+
+function buildFragment( elems, context, scripts, selection, ignored ) {
+	var elem, tmp, tag, wrap, contains, j,
+		fragment = context.createDocumentFragment(),
+		nodes = [],
+		i = 0,
+		l = elems.length;
+
+	for ( ; i < l; i++ ) {
+		elem = elems[ i ];
+
+		if ( elem || elem === 0 ) {
+
+			// Add nodes directly
+			if ( jQuery.type( elem ) === "object" ) {
+
+				// Support: Android<4.1, PhantomJS<2
+				// push.apply(_, arraylike) throws on ancient WebKit
+				jQuery.merge( nodes, elem.nodeType ? [ elem ] : elem );
+
+			// Convert non-html into a text node
+			} else if ( !rhtml.test( elem ) ) {
+				nodes.push( context.createTextNode( elem ) );
+
+			// Convert html into DOM nodes
+			} else {
+				tmp = tmp || fragment.appendChild( context.createElement( "div" ) );
+
+				// Deserialize a standard representation
+				tag = ( rtagName.exec( elem ) || [ "", "" ] )[ 1 ].toLowerCase();
+				wrap = wrapMap[ tag ] || wrapMap._default;
+				tmp.innerHTML = wrap[ 1 ] + jQuery.htmlPrefilter( elem ) + wrap[ 2 ];
+
+				// Descend through wrappers to the right content
+				j = wrap[ 0 ];
+				while ( j-- ) {
+					tmp = tmp.lastChild;
+				}
+
+				// Support: Android<4.1, PhantomJS<2
+				// push.apply(_, arraylike) throws on ancient WebKit
+				jQuery.merge( nodes, tmp.childNodes );
+
+				// Remember the top-level container
+				tmp = fragment.firstChild;
+
+				// Ensure the created nodes are orphaned (#12392)
+				tmp.textContent = "";
+			}
+		}
+	}
+
+	// Remove wrapper from fragment
+	fragment.textContent = "";
+
+	i = 0;
+	while ( ( elem = nodes[ i++ ] ) ) {
+
+		// Skip elements already in the context collection (trac-4087)
+		if ( selection && jQuery.inArray( elem, selection ) > -1 ) {
+			if ( ignored ) {
+				ignored.push( elem );
+			}
+			continue;
+		}
+
+		contains = jQuery.contains( elem.ownerDocument, elem );
+
+		// Append to fragment
+		tmp = getAll( fragment.appendChild( elem ), "script" );
+
+		// Preserve script evaluation history
+		if ( contains ) {
+			setGlobalEval( tmp );
+		}
+
+		// Capture executables
+		if ( scripts ) {
+			j = 0;
+			while ( ( elem = tmp[ j++ ] ) ) {
+				if ( rscriptType.test( elem.type || "" ) ) {
+					scripts.push( elem );
+				}
+			}
+		}
+	}
+
+	return fragment;
+}
+
+
+( function() {
+	var fragment = document.createDocumentFragment(),
+		div = fragment.appendChild( document.createElement( "div" ) ),
+		input = document.createElement( "input" );
+
+	// Support: Android 4.0-4.3, Safari<=5.1
+	// Check state lost if the name is set (#11217)
+	// Support: Windows Web Apps (WWA)
+	// `name` and `type` must use .setAttribute for WWA (#14901)
+	input.setAttribute( "type", "radio" );
+	input.setAttribute( "checked", "checked" );
+	input.setAttribute( "name", "t" );
+
+	div.appendChild( input );
+
+	// Support: Safari<=5.1, Android<4.2
+	// Older WebKit doesn't clone checked state correctly in fragments
+	support.checkClone = div.cloneNode( true ).cloneNode( true ).lastChild.checked;
+
+	// Support: IE<=11+
+	// Make sure textarea (and checkbox) defaultValue is properly cloned
+	div.innerHTML = "<textarea>x</textarea>";
+	support.noCloneChecked = !!div.cloneNode( true ).lastChild.defaultValue;
+} )();
+
+
+var
+	rkeyEvent = /^key/,
+	rmouseEvent = /^(?:mouse|pointer|contextmenu|drag|drop)|click/,
+	rtypenamespace = /^([^.]*)(?:\.(.+)|)/;
+
+function returnTrue() {
+	return true;
+}
+
+function returnFalse() {
+	return false;
+}
+
+// Support: IE9
+// See #13393 for more info
+function safeActiveElement() {
+	try {
+		return document.activeElement;
+	} catch ( err ) { }
+}
+
+function on( elem, types, selector, data, fn, one ) {
+	var origFn, type;
+
+	// Types can be a map of types/handlers
+	if ( typeof types === "object" ) {
+
+		// ( types-Object, selector, data )
+		if ( typeof selector !== "string" ) {
+
+			// ( types-Object, data )
+			data = data || selector;
+			selector = undefined;
+		}
+		for ( type in types ) {
+			on( elem, type, selector, data, types[ type ], one );
+		}
+		return elem;
+	}
+
+	if ( data == null && fn == null ) {
+
+		// ( types, fn )
+		fn = selector;
+		data = selector = undefined;
+	} else if ( fn == null ) {
+		if ( typeof selector === "string" ) {
+
+			// ( types, selector, fn )
+			fn = data;
+			data = undefined;
+		} else {
+
+			// ( types, data, fn )
+			fn = data;
+			data = selector;
+			selector = undefined;
+		}
+	}
+	if ( fn === false ) {
+		fn = returnFalse;
+	} else if ( !fn ) {
+		return this;
+	}
+
+	if ( one === 1 ) {
+		origFn = fn;
+		fn = function( event ) {
+
+			// Can use an empty set, since event contains the info
+			jQuery().off( event );
+			return origFn.apply( this, arguments );
+		};
+
+		// Use same guid so caller can remove using origFn
+		fn.guid = origFn.guid || ( origFn.guid = jQuery.guid++ );
+	}
+	return elem.each( function() {
+		jQuery.event.add( this, types, fn, data, selector );
+	} );
+}
+
+/*
+ * Helper functions for managing events -- not part of the public interface.
+ * Props to Dean Edwards' addEvent library for many of the ideas.
+ */
+jQuery.event = {
+
+	global: {},
+
+	add: function( elem, types, handler, data, selector ) {
+
+		var handleObjIn, eventHandle, tmp,
+			events, t, handleObj,
+			special, handlers, type, namespaces, origType,
+			elemData = dataPriv.get( elem );
+
+		// Don't attach events to noData or text/comment nodes (but allow plain objects)
+		if ( !elemData ) {
+			return;
+		}
+
+		// Caller can pass in an object of custom data in lieu of the handler
+		if ( handler.handler ) {
+			handleObjIn = handler;
+			handler = handleObjIn.handler;
+			selector = handleObjIn.selector;
+		}
+
+		// Make sure that the handler has a unique ID, used to find/remove it later
+		if ( !handler.guid ) {
+			handler.guid = jQuery.guid++;
+		}
+
+		// Init the element's event structure and main handler, if this is the first
+		if ( !( events = elemData.events ) ) {
+			events = elemData.events = {};
+		}
+		if ( !( eventHandle = elemData.handle ) ) {
+			eventHandle = elemData.handle = function( e ) {
+
+				// Discard the second event of a jQuery.event.trigger() and
+				// when an event is called after a page has unloaded
+				return typeof jQuery !== "undefined" && jQuery.event.triggered !== e.type ?
+					jQuery.event.dispatch.apply( elem, arguments ) : undefined;
+			};
+		}
+
+		// Handle multiple events separated by a space
+		types = ( types || "" ).match( rnotwhite ) || [ "" ];
+		t = types.length;
+		while ( t-- ) {
+			tmp = rtypenamespace.exec( types[ t ] ) || [];
+			type = origType = tmp[ 1 ];
+			namespaces = ( tmp[ 2 ] || "" ).split( "." ).sort();
+
+			// There *must* be a type, no attaching namespace-only handlers
+			if ( !type ) {
+				continue;
+			}
+
+			// If event changes its type, use the special event handlers for the changed type
+			special = jQuery.event.special[ type ] || {};
+
+			// If selector defined, determine special event api type, otherwise given type
+			type = ( selector ? special.delegateType : special.bindType ) || type;
+
+			// Update special based on newly reset type
+			special = jQuery.event.special[ type ] || {};
+
+			// handleObj is passed to all event handlers
+			handleObj = jQuery.extend( {
+				type: type,
+				origType: origType,
+				data: data,
+				handler: handler,
+				guid: handler.guid,
+				selector: selector,
+				needsContext: selector && jQuery.expr.match.needsContext.test( selector ),
+				namespace: namespaces.join( "." )
+			}, handleObjIn );
+
+			// Init the event handler queue if we're the first
+			if ( !( handlers = events[ type ] ) ) {
+				handlers = events[ type ] = [];
+				handlers.delegateCount = 0;
+
+				// Only use addEventListener if the special events handler returns false
+				if ( !special.setup ||
+					special.setup.call( elem, data, namespaces, eventHandle ) === false ) {
+
+					if ( elem.addEventListener ) {
+						elem.addEventListener( type, eventHandle );
+					}
+				}
+			}
+
+			if ( special.add ) {
+				special.add.call( elem, handleObj );
+
+				if ( !handleObj.handler.guid ) {
+					handleObj.handler.guid = handler.guid;
+				}
+			}
+
+			// Add to the element's handler list, delegates in front
+			if ( selector ) {
+				handlers.splice( handlers.delegateCount++, 0, handleObj );
+			} else {
+				handlers.push( handleObj );
+			}
+
+			// Keep track of which events have ever been used, for event optimization
+			jQuery.event.global[ type ] = true;
+		}
+
+	},
+
+	// Detach an event or set of events from an element
+	remove: function( elem, types, handler, selector, mappedTypes ) {
+
+		var j, origCount, tmp,
+			events, t, handleObj,
+			special, handlers, type, namespaces, origType,
+			elemData = dataPriv.hasData( elem ) && dataPriv.get( elem );
+
+		if ( !elemData || !( events = elemData.events ) ) {
+			return;
+		}
+
+		// Once for each type.namespace in types; type may be omitted
+		types = ( types || "" ).match( rnotwhite ) || [ "" ];
+		t = types.length;
+		while ( t-- ) {
+			tmp = rtypenamespace.exec( types[ t ] ) || [];
+			type = origType = tmp[ 1 ];
+			namespaces = ( tmp[ 2 ] || "" ).split( "." ).sort();
+
+			// Unbind all events (on this namespace, if provided) for the element
+			if ( !type ) {
+				for ( type in events ) {
+					jQuery.event.remove( elem, type + types[ t ], handler, selector, true );
+				}
+				continue;
+			}
+
+			special = jQuery.event.special[ type ] || {};
+			type = ( selector ? special.delegateType : special.bindType ) || type;
+			handlers = events[ type ] || [];
+			tmp = tmp[ 2 ] &&
+				new RegExp( "(^|\\.)" + namespaces.join( "\\.(?:.*\\.|)" ) + "(\\.|$)" );
+
+			// Remove matching events
+			origCount = j = handlers.length;
+			while ( j-- ) {
+				handleObj = handlers[ j ];
+
+				if ( ( mappedTypes || origType === handleObj.origType ) &&
+					( !handler || handler.guid === handleObj.guid ) &&
+					( !tmp || tmp.test( handleObj.namespace ) ) &&
+					( !selector || selector === handleObj.selector ||
+						selector === "**" && handleObj.selector ) ) {
+					handlers.splice( j, 1 );
+
+					if ( handleObj.selector ) {
+						handlers.delegateCount--;
+					}
+					if ( special.remove ) {
+						special.remove.call( elem, handleObj );
+					}
+				}
+			}
+
+			// Remove generic event handler if we removed something and no more handlers exist
+			// (avoids potential for endless recursion during removal of special event handlers)
+			if ( origCount && !handlers.length ) {
+				if ( !special.teardown ||
+					special.teardown.call( elem, namespaces, elemData.handle ) === false ) {
+
+					jQuery.removeEvent( elem, type, elemData.handle );
+				}
+
+				delete events[ type ];
+			}
+		}
+
+		// Remove data and the expando if it's no longer used
+		if ( jQuery.isEmptyObject( events ) ) {
+			dataPriv.remove( elem, "handle events" );
+		}
+	},
+
+	dispatch: function( event ) {
+
+		// Make a writable jQuery.Event from the native event object
+		event = jQuery.event.fix( event );
+
+		var i, j, ret, matched, handleObj,
+			handlerQueue = [],
+			args = slice.call( arguments ),
+			handlers = ( dataPriv.get( this, "events" ) || {} )[ event.type ] || [],
+			special = jQuery.event.special[ event.type ] || {};
+
+		// Use the fix-ed jQuery.Event rather than the (read-only) native event
+		args[ 0 ] = event;
+		event.delegateTarget = this;
+
+		// Call the preDispatch hook for the mapped type, and let it bail if desired
+		if ( special.preDispatch && special.preDispatch.call( this, event ) === false ) {
+			return;
+		}
+
+		// Determine handlers
+		handlerQueue = jQuery.event.handlers.call( this, event, handlers );
+
+		// Run delegates first; they may want to stop propagation beneath us
+		i = 0;
+		while ( ( matched = handlerQueue[ i++ ] ) && !event.isPropagationStopped() ) {
+			event.currentTarget = matched.elem;
+
+			j = 0;
+			while ( ( handleObj = matched.handlers[ j++ ] ) &&
+				!event.isImmediatePropagationStopped() ) {
+
+				// Triggered event must either 1) have no namespace, or 2) have namespace(s)
+				// a subset or equal to those in the bound event (both can have no namespace).
+				if ( !event.rnamespace || event.rnamespace.test( handleObj.namespace ) ) {
+
+					event.handleObj = handleObj;
+					event.data = handleObj.data;
+
+					ret = ( ( jQuery.event.special[ handleObj.origType ] || {} ).handle ||
+						handleObj.handler ).apply( matched.elem, args );
+
+					if ( ret !== undefined ) {
+						if ( ( event.result = ret ) === false ) {
+							event.preventDefault();
+							event.stopPropagation();
+						}
+					}
+				}
+			}
+		}
+
+		// Call the postDispatch hook for the mapped type
+		if ( special.postDispatch ) {
+			special.postDispatch.call( this, event );
+		}
+
+		return event.result;
+	},
+
+	handlers: function( event, handlers ) {
+		var i, matches, sel, handleObj,
+			handlerQueue = [],
+			delegateCount = handlers.delegateCount,
+			cur = event.target;
+
+		// Support (at least): Chrome, IE9
+		// Find delegate handlers
+		// Black-hole SVG <use> instance trees (#13180)
+		//
+		// Support: Firefox<=42+
+		// Avoid non-left-click in FF but don't block IE radio events (#3861, gh-2343)
+		if ( delegateCount && cur.nodeType &&
+			( event.type !== "click" || isNaN( event.button ) || event.button < 1 ) ) {
+
+			for ( ; cur !== this; cur = cur.parentNode || this ) {
+
+				// Don't check non-elements (#13208)
+				// Don't process clicks on disabled elements (#6911, #8165, #11382, #11764)
+				if ( cur.nodeType === 1 && ( cur.disabled !== true || event.type !== "click" ) ) {
+					matches = [];
+					for ( i = 0; i < delegateCount; i++ ) {
+						handleObj = handlers[ i ];
+
+						// Don't conflict with Object.prototype properties (#13203)
+						sel = handleObj.selector + " ";
+
+						if ( matches[ sel ] === undefined ) {
+							matches[ sel ] = handleObj.needsContext ?
+								jQuery( sel, this ).index( cur ) > -1 :
+								jQuery.find( sel, this, null, [ cur ] ).length;
+						}
+						if ( matches[ sel ] ) {
+							matches.push( handleObj );
+						}
+					}
+					if ( matches.length ) {
+						handlerQueue.push( { elem: cur, handlers: matches } );
+					}
+				}
+			}
+		}
+
+		// Add the remaining (directly-bound) handlers
+		if ( delegateCount < handlers.length ) {
+			handlerQueue.push( { elem: this, handlers: handlers.slice( delegateCount ) } );
+		}
+
+		return handlerQueue;
+	},
+
+	// Includes some event props shared by KeyEvent and MouseEvent
+	props: ( "altKey bubbles cancelable ctrlKey currentTarget detail eventPhase " +
+		"metaKey relatedTarget shiftKey target timeStamp view which" ).split( " " ),
+
+	fixHooks: {},
+
+	keyHooks: {
+		props: "char charCode key keyCode".split( " " ),
+		filter: function( event, original ) {
+
+			// Add which for key events
+			if ( event.which == null ) {
+				event.which = original.charCode != null ? original.charCode : original.keyCode;
+			}
+
+			return event;
+		}
+	},
+
+	mouseHooks: {
+		props: ( "button buttons clientX clientY offsetX offsetY pageX pageY " +
+			"screenX screenY toElement" ).split( " " ),
+		filter: function( event, original ) {
+			var eventDoc, doc, body,
+				button = original.button;
+
+			// Calculate pageX/Y if missing and clientX/Y available
+			if ( event.pageX == null && original.clientX != null ) {
+				eventDoc = event.target.ownerDocument || document;
+				doc = eventDoc.documentElement;
+				body = eventDoc.body;
+
+				event.pageX = original.clientX +
+					( doc && doc.scrollLeft || body && body.scrollLeft || 0 ) -
+					( doc && doc.clientLeft || body && body.clientLeft || 0 );
+				event.pageY = original.clientY +
+					( doc && doc.scrollTop  || body && body.scrollTop  || 0 ) -
+					( doc && doc.clientTop  || body && body.clientTop  || 0 );
+			}
+
+			// Add which for click: 1 === left; 2 === middle; 3 === right
+			// Note: button is not normalized, so don't use it
+			if ( !event.which && button !== undefined ) {
+				event.which = ( button & 1 ? 1 : ( button & 2 ? 3 : ( button & 4 ? 2 : 0 ) ) );
+			}
+
+			return event;
+		}
+	},
+
+	fix: function( event ) {
+		if ( event[ jQuery.expando ] ) {
+			return event;
+		}
+
+		// Create a writable copy of the event object and normalize some properties
+		var i, prop, copy,
+			type = event.type,
+			originalEvent = event,
+			fixHook = this.fixHooks[ type ];
+
+		if ( !fixHook ) {
+			this.fixHooks[ type ] = fixHook =
+				rmouseEvent.test( type ) ? this.mouseHooks :
+				rkeyEvent.test( type ) ? this.keyHooks :
+				{};
+		}
+		copy = fixHook.props ? this.props.concat( fixHook.props ) : this.props;
+
+		event = new jQuery.Event( originalEvent );
+
+		i = copy.length;
+		while ( i-- ) {
+			prop = copy[ i ];
+			event[ prop ] = originalEvent[ prop ];
+		}
+
+		// Support: Cordova 2.5 (WebKit) (#13255)
+		// All events should have a target; Cordova deviceready doesn't
+		if ( !event.target ) {
+			event.target = document;
+		}
+
+		// Support: Safari 6.0+, Chrome<28
+		// Target should not be a text node (#504, #13143)
+		if ( event.target.nodeType === 3 ) {
+			event.target = event.target.parentNode;
+		}
+
+		return fixHook.filter ? fixHook.filter( event, originalEvent ) : event;
+	},
+
+	special: {
+		load: {
+
+			// Prevent triggered image.load events from bubbling to window.load
+			noBubble: true
+		},
+		focus: {
+
+			// Fire native event if possible so blur/focus sequence is correct
+			trigger: function() {
+				if ( this !== safeActiveElement() && this.focus ) {
+					this.focus();
+					return false;
+				}
+			},
+			delegateType: "focusin"
+		},
+		blur: {
+			trigger: function() {
+				if ( this === safeActiveElement() && this.blur ) {
+					this.blur();
+					return false;
+				}
+			},
+			delegateType: "focusout"
+		},
+		click: {
+
+			// For checkbox, fire native event so checked state will be right
+			trigger: function() {
+				if ( this.type === "checkbox" && this.click && jQuery.nodeName( this, "input" ) ) {
+					this.click();
+					return false;
+				}
+			},
+
+			// For cross-browser consistency, don't fire native .click() on links
+			_default: function( event ) {
+				return jQuery.nodeName( event.target, "a" );
+			}
+		},
+
+		beforeunload: {
+			postDispatch: function( event ) {
+
+				// Support: Firefox 20+
+				// Firefox doesn't alert if the returnValue field is not set.
+				if ( event.result !== undefined && event.originalEvent ) {
+					event.originalEvent.returnValue = event.result;
+				}
+			}
+		}
+	}
+};
+
+jQuery.removeEvent = function( elem, type, handle ) {
+
+	// This "if" is needed for plain objects
+	if ( elem.removeEventListener ) {
+		elem.removeEventListener( type, handle );
+	}
+};
+
+jQuery.Event = function( src, props ) {
+
+	// Allow instantiation without the 'new' keyword
+	if ( !( this instanceof jQuery.Event ) ) {
+		return new jQuery.Event( src, props );
+	}
+
+	// Event object
+	if ( src && src.type ) {
+		this.originalEvent = src;
+		this.type = src.type;
+
+		// Events bubbling up the document may have been marked as prevented
+		// by a handler lower down the tree; reflect the correct value.
+		this.isDefaultPrevented = src.defaultPrevented ||
+				src.defaultPrevented === undefined &&
+
+				// Support: Android<4.0
+				src.returnValue === false ?
+			returnTrue :
+			returnFalse;
+
+	// Event type
+	} else {
+		this.type = src;
+	}
+
+	// Put explicitly provided properties onto the event object
+	if ( props ) {
+		jQuery.extend( this, props );
+	}
+
+	// Create a timestamp if incoming event doesn't have one
+	this.timeStamp = src && src.timeStamp || jQuery.now();
+
+	// Mark it as fixed
+	this[ jQuery.expando ] = true;
+};
+
+// jQuery.Event is based on DOM3 Events as specified by the ECMAScript Language Binding
+// http://www.w3.org/TR/2003/WD-DOM-Level-3-Events-20030331/ecma-script-binding.html
+jQuery.Event.prototype = {
+	constructor: jQuery.Event,
+	isDefaultPrevented: returnFalse,
+	isPropagationStopped: returnFalse,
+	isImmediatePropagationStopped: returnFalse,
+
+	preventDefault: function() {
+		var e = this.originalEvent;
+
+		this.isDefaultPrevented = returnTrue;
+
+		if ( e ) {
+			e.preventDefault();
+		}
+	},
+	stopPropagation: function() {
+		var e = this.originalEvent;
+
+		this.isPropagationStopped = returnTrue;
+
+		if ( e ) {
+			e.stopPropagation();
+		}
+	},
+	stopImmediatePropagation: function() {
+		var e = this.originalEvent;
+
+		this.isImmediatePropagationStopped = returnTrue;
+
+		if ( e ) {
+			e.stopImmediatePropagation();
+		}
+
+		this.stopPropagation();
+	}
+};
+
+// Create mouseenter/leave events using mouseover/out and event-time checks
+// so that event delegation works in jQuery.
+// Do the same for pointerenter/pointerleave and pointerover/pointerout
+//
+// Support: Safari 7 only
+// Safari sends mouseenter too often; see:
+// https://code.google.com/p/chromium/issues/detail?id=470258
+// for the description of the bug (it existed in older Chrome versions as well).
+jQuery.each( {
+	mouseenter: "mouseover",
+	mouseleave: "mouseout",
+	pointerenter: "pointerover",
+	pointerleave: "pointerout"
+}, function( orig, fix ) {
+	jQuery.event.special[ orig ] = {
+		delegateType: fix,
+		bindType: fix,
+
+		handle: function( event ) {
+			var ret,
+				target = this,
+				related = event.relatedTarget,
+				handleObj = event.handleObj;
+
+			// For mouseenter/leave call the handler if related is outside the target.
+			// NB: No relatedTarget if the mouse left/entered the browser window
+			if ( !related || ( related !== target && !jQuery.contains( target, related ) ) ) {
+				event.type = handleObj.origType;
+				ret = handleObj.handler.apply( this, arguments );
+				event.type = fix;
+			}
+			return ret;
+		}
+	};
+} );
+
+jQuery.fn.extend( {
+	on: function( types, selector, data, fn ) {
+		return on( this, types, selector, data, fn );
+	},
+	one: function( types, selector, data, fn ) {
+		return on( this, types, selector, data, fn, 1 );
+	},
+	off: function( types, selector, fn ) {
+		var handleObj, type;
+		if ( types && types.preventDefault && types.handleObj ) {
+
+			// ( event )  dispatched jQuery.Event
+			handleObj = types.handleObj;
+			jQuery( types.delegateTarget ).off(
+				handleObj.namespace ?
+					handleObj.origType + "." + handleObj.namespace :
+					handleObj.origType,
+				handleObj.selector,
+				handleObj.handler
+			);
+			return this;
+		}
+		if ( typeof types === "object" ) {
+
+			// ( types-object [, selector] )
+			for ( type in types ) {
+				this.off( type, selector, types[ type ] );
+			}
+			return this;
+		}
+		if ( selector === false || typeof selector === "function" ) {
+
+			// ( types [, fn] )
+			fn = selector;
+			selector = undefined;
+		}
+		if ( fn === false ) {
+			fn = returnFalse;
+		}
+		return this.each( function() {
+			jQuery.event.remove( this, types, fn, selector );
+		} );
+	}
+} );
+
+
+var
+	rxhtmlTag = /<(?!area|br|col|embed|hr|img|input|link|meta|param)(([\w:-]+)[^>]*)\/>/gi,
+
+	// Support: IE 10-11, Edge 10240+
+	// In IE/Edge using regex groups here causes severe slowdowns.
+	// See https://connect.microsoft.com/IE/feedback/details/1736512/
+	rnoInnerhtml = /<script|<style|<link/i,
+
+	// checked="checked" or checked
+	rchecked = /checked\s*(?:[^=]|=\s*.checked.)/i,
+	rscriptTypeMasked = /^true\/(.*)/,
+	rcleanScript = /^\s*<!(?:\[CDATA\[|--)|(?:\]\]|--)>\s*$/g;
+
+function manipulationTarget( elem, content ) {
+	if ( jQuery.nodeName( elem, "table" ) &&
+		jQuery.nodeName( content.nodeType !== 11 ? content : content.firstChild, "tr" ) ) {
+
+		return elem.getElementsByTagName( "tbody" )[ 0 ] || elem;
+	}
+
+	return elem;
+}
+
+// Replace/restore the type attribute of script elements for safe DOM manipulation
+function disableScript( elem ) {
+	elem.type = ( elem.getAttribute( "type" ) !== null ) + "/" + elem.type;
+	return elem;
+}
+function restoreScript( elem ) {
+	var match = rscriptTypeMasked.exec( elem.type );
+
+	if ( match ) {
+		elem.type = match[ 1 ];
+	} else {
+		elem.removeAttribute( "type" );
+	}
+
+	return elem;
+}
+
+function cloneCopyEvent( src, dest ) {
+	var i, l, type, pdataOld, pdataCur, udataOld, udataCur, events;
+
+	if ( dest.nodeType !== 1 ) {
+		return;
+	}
+
+	// 1. Copy private data: events, handlers, etc.
+	if ( dataPriv.hasData( src ) ) {
+		pdataOld = dataPriv.access( src );
+		pdataCur = dataPriv.set( dest, pdataOld );
+		events = pdataOld.events;
+
+		if ( events ) {
+			delete pdataCur.handle;
+			pdataCur.events = {};
+
+			for ( type in events ) {
+				for ( i = 0, l = events[ type ].length; i < l; i++ ) {
+					jQuery.event.add( dest, type, events[ type ][ i ] );
+				}
+			}
+		}
+	}
+
+	// 2. Copy user data
+	if ( dataUser.hasData( src ) ) {
+		udataOld = dataUser.access( src );
+		udataCur = jQuery.extend( {}, udataOld );
+
+		dataUser.set( dest, udataCur );
+	}
+}
+
+// Fix IE bugs, see support tests
+function fixInput( src, dest ) {
+	var nodeName = dest.nodeName.toLowerCase();
+
+	// Fails to persist the checked state of a cloned checkbox or radio button.
+	if ( nodeName === "input" && rcheckableType.test( src.type ) ) {
+		dest.checked = src.checked;
+
+	// Fails to return the selected option to the default selected state when cloning options
+	} else if ( nodeName === "input" || nodeName === "textarea" ) {
+		dest.defaultValue = src.defaultValue;
+	}
+}
+
+function domManip( collection, args, callback, ignored ) {
+
+	// Flatten any nested arrays
+	args = concat.apply( [], args );
+
+	var fragment, first, scripts, hasScripts, node, doc,
+		i = 0,
+		l = collection.length,
+		iNoClone = l - 1,
+		value = args[ 0 ],
+		isFunction = jQuery.isFunction( value );
+
+	// We can't cloneNode fragments that contain checked, in WebKit
+	if ( isFunction ||
+			( l > 1 && typeof value === "string" &&
+				!support.checkClone && rchecked.test( value ) ) ) {
+		return collection.each( function( index ) {
+			var self = collection.eq( index );
+			if ( isFunction ) {
+				args[ 0 ] = value.call( this, index, self.html() );
+			}
+			domManip( self, args, callback, ignored );
+		} );
+	}
+
+	if ( l ) {
+		fragment = buildFragment( args, collection[ 0 ].ownerDocument, false, collection, ignored );
+		first = fragment.firstChild;
+
+		if ( fragment.childNodes.length === 1 ) {
+			fragment = first;
+		}
+
+		// Require either new content or an interest in ignored elements to invoke the callback
+		if ( first || ignored ) {
+			scripts = jQuery.map( getAll( fragment, "script" ), disableScript );
+			hasScripts = scripts.length;
+
+			// Use the original fragment for the last item
+			// instead of the first because it can end up
+			// being emptied incorrectly in certain situations (#8070).
+			for ( ; i < l; i++ ) {
+				node = fragment;
+
+				if ( i !== iNoClone ) {
+					node = jQuery.clone( node, true, true );
+
+					// Keep references to cloned scripts for later restoration
+					if ( hasScripts ) {
+
+						// Support: Android<4.1, PhantomJS<2
+						// push.apply(_, arraylike) throws on ancient WebKit
+						jQuery.merge( scripts, getAll( node, "script" ) );
+					}
+				}
+
+				callback.call( collection[ i ], node, i );
+			}
+
+			if ( hasScripts ) {
+				doc = scripts[ scripts.length - 1 ].ownerDocument;
+
+				// Reenable scripts
+				jQuery.map( scripts, restoreScript );
+
+				// Evaluate executable scripts on first document insertion
+				for ( i = 0; i < hasScripts; i++ ) {
+					node = scripts[ i ];
+					if ( rscriptType.test( node.type || "" ) &&
+						!dataPriv.access( node, "globalEval" ) &&
+						jQuery.contains( doc, node ) ) {
+
+						if ( node.src ) {
+
+							// Optional AJAX dependency, but won't run scripts if not present
+							if ( jQuery._evalUrl ) {
+								jQuery._evalUrl( node.src );
+							}
+						} else {
+							jQuery.globalEval( node.textContent.replace( rcleanScript, "" ) );
+						}
+					}
+				}
+			}
+		}
+	}
+
+	return collection;
+}
+
+function remove( elem, selector, keepData ) {
+	var node,
+		nodes = selector ? jQuery.filter( selector, elem ) : elem,
+		i = 0;
+
+	for ( ; ( node = nodes[ i ] ) != null; i++ ) {
+		if ( !keepData && node.nodeType === 1 ) {
+			jQuery.cleanData( getAll( node ) );
+		}
+
+		if ( node.parentNode ) {
+			if ( keepData && jQuery.contains( node.ownerDocument, node ) ) {
+				setGlobalEval( getAll( node, "script" ) );
+			}
+			node.parentNode.removeChild( node );
+		}
+	}
+
+	return elem;
+}
+
+jQuery.extend( {
+	htmlPrefilter: function( html ) {
+		return html.replace( rxhtmlTag, "<$1></$2>" );
+	},
+
+	clone: function( elem, dataAndEvents, deepDataAndEvents ) {
+		var i, l, srcElements, destElements,
+			clone = elem.cloneNode( true ),
+			inPage = jQuery.contains( elem.ownerDocument, elem );
+
+		// Fix IE cloning issues
+		if ( !support.noCloneChecked && ( elem.nodeType === 1 || elem.nodeType === 11 ) &&
+				!jQuery.isXMLDoc( elem ) ) {
+
+			// We eschew Sizzle here for performance reasons: http://jsperf.com/getall-vs-sizzle/2
+			destElements = getAll( clone );
+			srcElements = getAll( elem );
+
+			for ( i = 0, l = srcElements.length; i < l; i++ ) {
+				fixInput( srcElements[ i ], destElements[ i ] );
+			}
+		}
+
+		// Copy the events from the original to the clone
+		if ( dataAndEvents ) {
+			if ( deepDataAndEvents ) {
+				srcElements = srcElements || getAll( elem );
+				destElements = destElements || getAll( clone );
+
+				for ( i = 0, l = srcElements.length; i < l; i++ ) {
+					cloneCopyEvent( srcElements[ i ], destElements[ i ] );
+				}
+			} else {
+				cloneCopyEvent( elem, clone );
+			}
+		}
+
+		// Preserve script evaluation history
+		destElements = getAll( clone, "script" );
+		if ( destElements.length > 0 ) {
+			setGlobalEval( destElements, !inPage && getAll( elem, "script" ) );
+		}
+
+		// Return the cloned set
+		return clone;
+	},
+
+	cleanData: function( elems ) {
+		var data, elem, type,
+			special = jQuery.event.special,
+			i = 0;
+
+		for ( ; ( elem = elems[ i ] ) !== undefined; i++ ) {
+			if ( acceptData( elem ) ) {
+				if ( ( data = elem[ dataPriv.expando ] ) ) {
+					if ( data.events ) {
+						for ( type in data.events ) {
+							if ( special[ type ] ) {
+								jQuery.event.remove( elem, type );
+
+							// This is a shortcut to avoid jQuery.event.remove's overhead
+							} else {
+								jQuery.removeEvent( elem, type, data.handle );
+							}
+						}
+					}
+
+					// Support: Chrome <= 35-45+
+					// Assign undefined instead of using delete, see Data#remove
+					elem[ dataPriv.expando ] = undefined;
+				}
+				if ( elem[ dataUser.expando ] ) {
+
+					// Support: Chrome <= 35-45+
+					// Assign undefined instead of using delete, see Data#remove
+					elem[ dataUser.expando ] = undefined;
+				}
+			}
+		}
+	}
+} );
+
+jQuery.fn.extend( {
+
+	// Keep domManip exposed until 3.0 (gh-2225)
+	domManip: domManip,
+
+	detach: function( selector ) {
+		return remove( this, selector, true );
+	},
+
+	remove: function( selector ) {
+		return remove( this, selector );
+	},
+
+	text: function( value ) {
+		return access( this, function( value ) {
+			return value === undefined ?
+				jQuery.text( this ) :
+				this.empty().each( function() {
+					if ( this.nodeType === 1 || this.nodeType === 11 || this.nodeType === 9 ) {
+						this.textContent = value;
+					}
+				} );
+		}, null, value, arguments.length );
+	},
+
+	append: function() {
+		return domManip( this, arguments, function( elem ) {
+			if ( this.nodeType === 1 || this.nodeType === 11 || this.nodeType === 9 ) {
+				var target = manipulationTarget( this, elem );
+				target.appendChild( elem );
+			}
+		} );
+	},
+
+	prepend: function() {
+		return domManip( this, arguments, function( elem ) {
+			if ( this.nodeType === 1 || this.nodeType === 11 || this.nodeType === 9 ) {
+				var target = manipulationTarget( this, elem );
+				target.insertBefore( elem, target.firstChild );
+			}
+		} );
+	},
+
+	before: function() {
+		return domManip( this, arguments, function( elem ) {
+			if ( this.parentNode ) {
+				this.parentNode.insertBefore( elem, this );
+			}
+		} );
+	},
+
+	after: function() {
+		return domManip( this, arguments, function( elem ) {
+			if ( this.parentNode ) {
+				this.parentNode.insertBefore( elem, this.nextSibling );
+			}
+		} );
+	},
+
+	empty: function() {
+		var elem,
+			i = 0;
+
+		for ( ; ( elem = this[ i ] ) != null; i++ ) {
+			if ( elem.nodeType === 1 ) {
+
+				// Prevent memory leaks
+				jQuery.cleanData( getAll( elem, false ) );
+
+				// Remove any remaining nodes
+				elem.textContent = "";
+			}
+		}
+
+		return this;
+	},
+
+	clone: function( dataAndEvents, deepDataAndEvents ) {
+		dataAndEvents = dataAndEvents == null ? false : dataAndEvents;
+		deepDataAndEvents = deepDataAndEvents == null ? dataAndEvents : deepDataAndEvents;
+
+		return this.map( function() {
+			return jQuery.clone( this, dataAndEvents, deepDataAndEvents );
+		} );
+	},
+
+	html: function( value ) {
+		return access( this, function( value ) {
+			var elem = this[ 0 ] || {},
+				i = 0,
+				l = this.length;
+
+			if ( value === undefined && elem.nodeType === 1 ) {
+				return elem.innerHTML;
+			}
+
+			// See if we can take a shortcut and just use innerHTML
+			if ( typeof value === "string" && !rnoInnerhtml.test( value ) &&
+				!wrapMap[ ( rtagName.exec( value ) || [ "", "" ] )[ 1 ].toLowerCase() ] ) {
+
+				value = jQuery.htmlPrefilter( value );
+
+				try {
+					for ( ; i < l; i++ ) {
+						elem = this[ i ] || {};
+
+						// Remove element nodes and prevent memory leaks
+						if ( elem.nodeType === 1 ) {
+							jQuery.cleanData( getAll( elem, false ) );
+							elem.innerHTML = value;
+						}
+					}
+
+					elem = 0;
+
+				// If using innerHTML throws an exception, use the fallback method
+				} catch ( e ) {}
+			}
+
+			if ( elem ) {
+				this.empty().append( value );
+			}
+		}, null, value, arguments.length );
+	},
+
+	replaceWith: function() {
+		var ignored = [];
+
+		// Make the changes, replacing each non-ignored context element with the new content
+		return domManip( this, arguments, function( elem ) {
+			var parent = this.parentNode;
+
+			if ( jQuery.inArray( this, ignored ) < 0 ) {
+				jQuery.cleanData( getAll( this ) );
+				if ( parent ) {
+					parent.replaceChild( elem, this );
+				}
+			}
+
+		// Force callback invocation
+		}, ignored );
+	}
+} );
+
+jQuery.each( {
+	appendTo: "append",
+	prependTo: "prepend",
+	insertBefore: "before",
+	insertAfter: "after",
+	replaceAll: "replaceWith"
+}, function( name, original ) {
+	jQuery.fn[ name ] = function( selector ) {
+		var elems,
+			ret = [],
+			insert = jQuery( selector ),
+			last = insert.length - 1,
+			i = 0;
+
+		for ( ; i <= last; i++ ) {
+			elems = i === last ? this : this.clone( true );
+			jQuery( insert[ i ] )[ original ]( elems );
+
+			// Support: QtWebKit
+			// .get() because push.apply(_, arraylike) throws
+			push.apply( ret, elems.get() );
+		}
+
+		return this.pushStack( ret );
+	};
+} );
+
+
+var iframe,
+	elemdisplay = {
+
+		// Support: Firefox
+		// We have to pre-define these values for FF (#10227)
+		HTML: "block",
+		BODY: "block"
+	};
+
+/**
+ * Retrieve the actual display of a element
+ * @param {String} name nodeName of the element
+ * @param {Object} doc Document object
+ */
+
+// Called only from within defaultDisplay
+function actualDisplay( name, doc ) {
+	var elem = jQuery( doc.createElement( name ) ).appendTo( doc.body ),
+
+		display = jQuery.css( elem[ 0 ], "display" );
+
+	// We don't have any data stored on the element,
+	// so use "detach" method as fast way to get rid of the element
+	elem.detach();
+
+	return display;
+}
+
+/**
+ * Try to determine the default display value of an element
+ * @param {String} nodeName
+ */
+function defaultDisplay( nodeName ) {
+	var doc = document,
+		display = elemdisplay[ nodeName ];
+
+	if ( !display ) {
+		display = actualDisplay( nodeName, doc );
+
+		// If the simple way fails, read from inside an iframe
+		if ( display === "none" || !display ) {
+
+			// Use the already-created iframe if possible
+			iframe = ( iframe || jQuery( "<iframe frameborder='0' width='0' height='0'/>" ) )
+				.appendTo( doc.documentElement );
+
+			// Always write a new HTML skeleton so Webkit and Firefox don't choke on reuse
+			doc = iframe[ 0 ].contentDocument;
+
+			// Support: IE
+			doc.write();
+			doc.close();
+
+			display = actualDisplay( nodeName, doc );
+			iframe.detach();
+		}
+
+		// Store the correct default display
+		elemdisplay[ nodeName ] = display;
+	}
+
+	return display;
+}
+var rmargin = ( /^margin/ );
+
+var rnumnonpx = new RegExp( "^(" + pnum + ")(?!px)[a-z%]+$", "i" );
+
+var getStyles = function( elem ) {
+
+		// Support: IE<=11+, Firefox<=30+ (#15098, #14150)
+		// IE throws on elements created in popups
+		// FF meanwhile throws on frame elements through "defaultView.getComputedStyle"
+		var view = elem.ownerDocument.defaultView;
+
+		if ( !view.opener ) {
+			view = window;
+		}
+
+		return view.getComputedStyle( elem );
+	};
+
+var swap = function( elem, options, callback, args ) {
+	var ret, name,
+		old = {};
+
+	// Remember the old values, and insert the new ones
+	for ( name in options ) {
+		old[ name ] = elem.style[ name ];
+		elem.style[ name ] = options[ name ];
+	}
+
+	ret = callback.apply( elem, args || [] );
+
+	// Revert the old values
+	for ( name in options ) {
+		elem.style[ name ] = old[ name ];
+	}
+
+	return ret;
+};
+
+
+var documentElement = document.documentElement;
+
+
+
+( function() {
+	var pixelPositionVal, boxSizingReliableVal, pixelMarginRightVal, reliableMarginLeftVal,
+		container = document.createElement( "div" ),
+		div = document.createElement( "div" );
+
+	// Finish early in limited (non-browser) environments
+	if ( !div.style ) {
+		return;
+	}
+
+	// Support: IE9-11+
+	// Style of cloned element affects source element cloned (#8908)
+	div.style.backgroundClip = "content-box";
+	div.cloneNode( true ).style.backgroundClip = "";
+	support.clearCloneStyle = div.style.backgroundClip === "content-box";
+
+	container.style.cssText = "border:0;width:8px;height:0;top:0;left:-9999px;" +
+		"padding:0;margin-top:1px;position:absolute";
+	container.appendChild( div );
+
+	// Executing both pixelPosition & boxSizingReliable tests require only one layout
+	// so they're executed at the same time to save the second computation.
+	function computeStyleTests() {
+		div.style.cssText =
+
+			// Support: Firefox<29, Android 2.3
+			// Vendor-prefix box-sizing
+			"-webkit-box-sizing:border-box;-moz-box-sizing:border-box;box-sizing:border-box;" +
+			"position:relative;display:block;" +
+			"margin:auto;border:1px;padding:1px;" +
+			"top:1%;width:50%";
+		div.innerHTML = "";
+		documentElement.appendChild( container );
+
+		var divStyle = window.getComputedStyle( div );
+		pixelPositionVal = divStyle.top !== "1%";
+		reliableMarginLeftVal = divStyle.marginLeft === "2px";
+		boxSizingReliableVal = divStyle.width === "4px";
+
+		// Support: Android 4.0 - 4.3 only
+		// Some styles come back with percentage values, even though they shouldn't
+		div.style.marginRight = "50%";
+		pixelMarginRightVal = divStyle.marginRight === "4px";
+
+		documentElement.removeChild( container );
+	}
+
+	jQuery.extend( support, {
+		pixelPosition: function() {
+
+			// This test is executed only once but we still do memoizing
+			// since we can use the boxSizingReliable pre-computing.
+			// No need to check if the test was already performed, though.
+			computeStyleTests();
+			return pixelPositionVal;
+		},
+		boxSizingReliable: function() {
+			if ( boxSizingReliableVal == null ) {
+				computeStyleTests();
+			}
+			return boxSizingReliableVal;
+		},
+		pixelMarginRight: function() {
+
+			// Support: Android 4.0-4.3
+			// We're checking for boxSizingReliableVal here instead of pixelMarginRightVal
+			// since that compresses better and they're computed together anyway.
+			if ( boxSizingReliableVal == null ) {
+				computeStyleTests();
+			}
+			return pixelMarginRightVal;
+		},
+		reliableMarginLeft: function() {
+
+			// Support: IE <=8 only, Android 4.0 - 4.3 only, Firefox <=3 - 37
+			if ( boxSizingReliableVal == null ) {
+				computeStyleTests();
+			}
+			return reliableMarginLeftVal;
+		},
+		reliableMarginRight: function() {
+
+			// Support: Android 2.3
+			// Check if div with explicit width and no margin-right incorrectly
+			// gets computed margin-right based on width of container. (#3333)
+			// WebKit Bug 13343 - getComputedStyle returns wrong value for margin-right
+			// This support function is only executed once so no memoizing is needed.
+			var ret,
+				marginDiv = div.appendChild( document.createElement( "div" ) );
+
+			// Reset CSS: box-sizing; display; margin; border; padding
+			marginDiv.style.cssText = div.style.cssText =
+
+				// Support: Android 2.3
+				// Vendor-prefix box-sizing
+				"-webkit-box-sizing:content-box;box-sizing:content-box;" +
+				"display:block;margin:0;border:0;padding:0";
+			marginDiv.style.marginRight = marginDiv.style.width = "0";
+			div.style.width = "1px";
+			documentElement.appendChild( container );
+
+			ret = !parseFloat( window.getComputedStyle( marginDiv ).marginRight );
+
+			documentElement.removeChild( container );
+			div.removeChild( marginDiv );
+
+			return ret;
+		}
+	} );
+} )();
+
+
+function curCSS( elem, name, computed ) {
+	var width, minWidth, maxWidth, ret,
+		style = elem.style;
+
+	computed = computed || getStyles( elem );
+
+	// Support: IE9
+	// getPropertyValue is only needed for .css('filter') (#12537)
+	if ( computed ) {
+		ret = computed.getPropertyValue( name ) || computed[ name ];
+
+		if ( ret === "" && !jQuery.contains( elem.ownerDocument, elem ) ) {
+			ret = jQuery.style( elem, name );
+		}
+
+		// A tribute to the "awesome hack by Dean Edwards"
+		// Android Browser returns percentage for some values,
+		// but width seems to be reliably pixels.
+		// This is against the CSSOM draft spec:
+		// http://dev.w3.org/csswg/cssom/#resolved-values
+		if ( !support.pixelMarginRight() && rnumnonpx.test( ret ) && rmargin.test( name ) ) {
+
+			// Remember the original values
+			width = style.width;
+			minWidth = style.minWidth;
+			maxWidth = style.maxWidth;
+
+			// Put in the new values to get a computed value out
+			style.minWidth = style.maxWidth = style.width = ret;
+			ret = computed.width;
+
+			// Revert the changed values
+			style.width = width;
+			style.minWidth = minWidth;
+			style.maxWidth = maxWidth;
+		}
+	}
+
+	return ret !== undefined ?
+
+		// Support: IE9-11+
+		// IE returns zIndex value as an integer.
+		ret + "" :
+		ret;
+}
+
+
+function addGetHookIf( conditionFn, hookFn ) {
+
+	// Define the hook, we'll check on the first run if it's really needed.
+	return {
+		get: function() {
+			if ( conditionFn() ) {
+
+				// Hook not needed (or it's not possible to use it due
+				// to missing dependency), remove it.
+				delete this.get;
+				return;
+			}
+
+			// Hook needed; redefine it so that the support test is not executed again.
+			return ( this.get = hookFn ).apply( this, arguments );
+		}
+	};
+}
+
+
+var
+
+	// Swappable if display is none or starts with table
+	// except "table", "table-cell", or "table-caption"
+	// See here for display values: https://developer.mozilla.org/en-US/docs/CSS/display
+	rdisplayswap = /^(none|table(?!-c[ea]).+)/,
+
+	cssShow = { position: "absolute", visibility: "hidden", display: "block" },
+	cssNormalTransform = {
+		letterSpacing: "0",
+		fontWeight: "400"
+	},
+
+	cssPrefixes = [ "Webkit", "O", "Moz", "ms" ],
+	emptyStyle = document.createElement( "div" ).style;
+
+// Return a css property mapped to a potentially vendor prefixed property
+function vendorPropName( name ) {
+
+	// Shortcut for names that are not vendor prefixed
+	if ( name in emptyStyle ) {
+		return name;
+	}
+
+	// Check for vendor prefixed names
+	var capName = name[ 0 ].toUpperCase() + name.slice( 1 ),
+		i = cssPrefixes.length;
+
+	while ( i-- ) {
+		name = cssPrefixes[ i ] + capName;
+		if ( name in emptyStyle ) {
+			return name;
+		}
+	}
+}
+
+function setPositiveNumber( elem, value, subtract ) {
+
+	// Any relative (+/-) values have already been
+	// normalized at this point
+	var matches = rcssNum.exec( value );
+	return matches ?
+
+		// Guard against undefined "subtract", e.g., when used as in cssHooks
+		Math.max( 0, matches[ 2 ] - ( subtract || 0 ) ) + ( matches[ 3 ] || "px" ) :
+		value;
+}
+
+function augmentWidthOrHeight( elem, name, extra, isBorderBox, styles ) {
+	var i = extra === ( isBorderBox ? "border" : "content" ) ?
+
+		// If we already have the right measurement, avoid augmentation
+		4 :
+
+		// Otherwise initialize for horizontal or vertical properties
+		name === "width" ? 1 : 0,
+
+		val = 0;
+
+	for ( ; i < 4; i += 2 ) {
+
+		// Both box models exclude margin, so add it if we want it
+		if ( extra === "margin" ) {
+			val += jQuery.css( elem, extra + cssExpand[ i ], true, styles );
+		}
+
+		if ( isBorderBox ) {
+
+			// border-box includes padding, so remove it if we want content
+			if ( extra === "content" ) {
+				val -= jQuery.css( elem, "padding" + cssExpand[ i ], true, styles );
+			}
+
+			// At this point, extra isn't border nor margin, so remove border
+			if ( extra !== "margin" ) {
+				val -= jQuery.css( elem, "border" + cssExpand[ i ] + "Width", true, styles );
+			}
+		} else {
+
+			// At this point, extra isn't content, so add padding
+			val += jQuery.css( elem, "padding" + cssExpand[ i ], true, styles );
+
+			// At this point, extra isn't content nor padding, so add border
+			if ( extra !== "padding" ) {
+				val += jQuery.css( elem, "border" + cssExpand[ i ] + "Width", true, styles );
+			}
+		}
+	}
+
+	return val;
+}
+
+function getWidthOrHeight( elem, name, extra ) {
+
+	// Start with offset property, which is equivalent to the border-box value
+	var valueIsBorderBox = true,
+		val = name === "width" ? elem.offsetWidth : elem.offsetHeight,
+		styles = getStyles( elem ),
+		isBorderBox = jQuery.css( elem, "boxSizing", false, styles ) === "border-box";
+
+	// Support: IE11 only
+	// In IE 11 fullscreen elements inside of an iframe have
+	// 100x too small dimensions (gh-1764).
+	if ( document.msFullscreenElement && window.top !== window ) {
+
+		// Support: IE11 only
+		// Running getBoundingClientRect on a disconnected node
+		// in IE throws an error.
+		if ( elem.getClientRects().length ) {
+			val = Math.round( elem.getBoundingClientRect()[ name ] * 100 );
+		}
+	}
+
+	// Some non-html elements return undefined for offsetWidth, so check for null/undefined
+	// svg - https://bugzilla.mozilla.org/show_bug.cgi?id=649285
+	// MathML - https://bugzilla.mozilla.org/show_bug.cgi?id=491668
+	if ( val <= 0 || val == null ) {
+
+		// Fall back to computed then uncomputed css if necessary
+		val = curCSS( elem, name, styles );
+		if ( val < 0 || val == null ) {
+			val = elem.style[ name ];
+		}
+
+		// Computed unit is not pixels. Stop here and return.
+		if ( rnumnonpx.test( val ) ) {
+			return val;
+		}
+
+		// Check for style in case a browser which returns unreliable values
+		// for getComputedStyle silently falls back to the reliable elem.style
+		valueIsBorderBox = isBorderBox &&
+			( support.boxSizingReliable() || val === elem.style[ name ] );
+
+		// Normalize "", auto, and prepare for extra
+		val = parseFloat( val ) || 0;
+	}
+
+	// Use the active box-sizing model to add/subtract irrelevant styles
+	return ( val +
+		augmentWidthOrHeight(
+			elem,
+			name,
+			extra || ( isBorderBox ? "border" : "content" ),
+			valueIsBorderBox,
+			styles
+		)
+	) + "px";
+}
+
+function showHide( elements, show ) {
+	var display, elem, hidden,
+		values = [],
+		index = 0,
+		length = elements.length;
+
+	for ( ; index < length; index++ ) {
+		elem = elements[ index ];
+		if ( !elem.style ) {
+			continue;
+		}
+
+		values[ index ] = dataPriv.get( elem, "olddisplay" );
+		display = elem.style.display;
+		if ( show ) {
+
+			// Reset the inline display of this element to learn if it is
+			// being hidden by cascaded rules or not
+			if ( !values[ index ] && display === "none" ) {
+				elem.style.display = "";
+			}
+
+			// Set elements which have been overridden with display: none
+			// in a stylesheet to whatever the default browser style is
+			// for such an element
+			if ( elem.style.display === "" && isHidden( elem ) ) {
+				values[ index ] = dataPriv.access(
+					elem,
+					"olddisplay",
+					defaultDisplay( elem.nodeName )
+				);
+			}
+		} else {
+			hidden = isHidden( elem );
+
+			if ( display !== "none" || !hidden ) {
+				dataPriv.set(
+					elem,
+					"olddisplay",
+					hidden ? display : jQuery.css( elem, "display" )
+				);
+			}
+		}
+	}
+
+	// Set the display of most of the elements in a second loop
+	// to avoid the constant reflow
+	for ( index = 0; index < length; index++ ) {
+		elem = elements[ index ];
+		if ( !elem.style ) {
+			continue;
+		}
+		if ( !show || elem.style.display === "none" || elem.style.display === "" ) {
+			elem.style.display = show ? values[ index ] || "" : "none";
+		}
+	}
+
+	return elements;
+}
+
+jQuery.extend( {
+
+	// Add in style property hooks for overriding the default
+	// behavior of getting and setting a style property
+	cssHooks: {
+		opacity: {
+			get: function( elem, computed ) {
+				if ( computed ) {
+
+					// We should always get a number back from opacity
+					var ret = curCSS( elem, "opacity" );
+					return ret === "" ? "1" : ret;
+				}
+			}
+		}
+	},
+
+	// Don't automatically add "px" to these possibly-unitless properties
+	cssNumber: {
+		"animationIterationCount": true,
+		"columnCount": true,
+		"fillOpacity": true,
+		"flexGrow": true,
+		"flexShrink": true,
+		"fontWeight": true,
+		"lineHeight": true,
+		"opacity": true,
+		"order": true,
+		"orphans": true,
+		"widows": true,
+		"zIndex": true,
+		"zoom": true
+	},
+
+	// Add in properties whose names you wish to fix before
+	// setting or getting the value
+	cssProps: {
+		"float": "cssFloat"
+	},
+
+	// Get and set the style property on a DOM Node
+	style: function( elem, name, value, extra ) {
+
+		// Don't set styles on text and comment nodes
+		if ( !elem || elem.nodeType === 3 || elem.nodeType === 8 || !elem.style ) {
+			return;
+		}
+
+		// Make sure that we're working with the right name
+		var ret, type, hooks,
+			origName = jQuery.camelCase( name ),
+			style = elem.style;
+
+		name = jQuery.cssProps[ origName ] ||
+			( jQuery.cssProps[ origName ] = vendorPropName( origName ) || origName );
+
+		// Gets hook for the prefixed version, then unprefixed version
+		hooks = jQuery.cssHooks[ name ] || jQuery.cssHooks[ origName ];
+
+		// Check if we're setting a value
+		if ( value !== undefined ) {
+			type = typeof value;
+
+			// Convert "+=" or "-=" to relative numbers (#7345)
+			if ( type === "string" && ( ret = rcssNum.exec( value ) ) && ret[ 1 ] ) {
+				value = adjustCSS( elem, name, ret );
+
+				// Fixes bug #9237
+				type = "number";
+			}
+
+			// Make sure that null and NaN values aren't set (#7116)
+			if ( value == null || value !== value ) {
+				return;
+			}
+
+			// If a number was passed in, add the unit (except for certain CSS properties)
+			if ( type === "number" ) {
+				value += ret && ret[ 3 ] || ( jQuery.cssNumber[ origName ] ? "" : "px" );
+			}
+
+			// Support: IE9-11+
+			// background-* props affect original clone's values
+			if ( !support.clearCloneStyle && value === "" && name.indexOf( "background" ) === 0 ) {
+				style[ name ] = "inherit";
+			}
+
+			// If a hook was provided, use that value, otherwise just set the specified value
+			if ( !hooks || !( "set" in hooks ) ||
+				( value = hooks.set( elem, value, extra ) ) !== undefined ) {
+
+				style[ name ] = value;
+			}
+
+		} else {
+
+			// If a hook was provided get the non-computed value from there
+			if ( hooks && "get" in hooks &&
+				( ret = hooks.get( elem, false, extra ) ) !== undefined ) {
+
+				return ret;
+			}
+
+			// Otherwise just get the value from the style object
+			return style[ name ];
+		}
+	},
+
+	css: function( elem, name, extra, styles ) {
+		var val, num, hooks,
+			origName = jQuery.camelCase( name );
+
+		// Make sure that we're working with the right name
+		name = jQuery.cssProps[ origName ] ||
+			( jQuery.cssProps[ origName ] = vendorPropName( origName ) || origName );
+
+		// Try prefixed name followed by the unprefixed name
+		hooks = jQuery.cssHooks[ name ] || jQuery.cssHooks[ origName ];
+
+		// If a hook was provided get the computed value from there
+		if ( hooks && "get" in hooks ) {
+			val = hooks.get( elem, true, extra );
+		}
+
+		// Otherwise, if a way to get the computed value exists, use that
+		if ( val === undefined ) {
+			val = curCSS( elem, name, styles );
+		}
+
+		// Convert "normal" to computed value
+		if ( val === "normal" && name in cssNormalTransform ) {
+			val = cssNormalTransform[ name ];
+		}
+
+		// Make numeric if forced or a qualifier was provided and val looks numeric
+		if ( extra === "" || extra ) {
+			num = parseFloat( val );
+			return extra === true || isFinite( num ) ? num || 0 : val;
+		}
+		return val;
+	}
+} );
+
+jQuery.each( [ "height", "width" ], function( i, name ) {
+	jQuery.cssHooks[ name ] = {
+		get: function( elem, computed, extra ) {
+			if ( computed ) {
+
+				// Certain elements can have dimension info if we invisibly show them
+				// but it must have a current display style that would benefit
+				return rdisplayswap.test( jQuery.css( elem, "display" ) ) &&
+					elem.offsetWidth === 0 ?
+						swap( elem, cssShow, function() {
+							return getWidthOrHeight( elem, name, extra );
+						} ) :
+						getWidthOrHeight( elem, name, extra );
+			}
+		},
+
+		set: function( elem, value, extra ) {
+			var matches,
+				styles = extra && getStyles( elem ),
+				subtract = extra && augmentWidthOrHeight(
+					elem,
+					name,
+					extra,
+					jQuery.css( elem, "boxSizing", false, styles ) === "border-box",
+					styles
+				);
+
+			// Convert to pixels if value adjustment is needed
+			if ( subtract && ( matches = rcssNum.exec( value ) ) &&
+				( matches[ 3 ] || "px" ) !== "px" ) {
+
+				elem.style[ name ] = value;
+				value = jQuery.css( elem, name );
+			}
+
+			return setPositiveNumber( elem, value, subtract );
+		}
+	};
+} );
+
+jQuery.cssHooks.marginLeft = addGetHookIf( support.reliableMarginLeft,
+	function( elem, computed ) {
+		if ( computed ) {
+			return ( parseFloat( curCSS( elem, "marginLeft" ) ) ||
+				elem.getBoundingClientRect().left -
+					swap( elem, { marginLeft: 0 }, function() {
+						return elem.getBoundingClientRect().left;
+					} )
+				) + "px";
+		}
+	}
+);
+
+// Support: Android 2.3
+jQuery.cssHooks.marginRight = addGetHookIf( support.reliableMarginRight,
+	function( elem, computed ) {
+		if ( computed ) {
+			return swap( elem, { "display": "inline-block" },
+				curCSS, [ elem, "marginRight" ] );
+		}
+	}
+);
+
+// These hooks are used by animate to expand properties
+jQuery.each( {
+	margin: "",
+	padding: "",
+	border: "Width"
+}, function( prefix, suffix ) {
+	jQuery.cssHooks[ prefix + suffix ] = {
+		expand: function( value ) {
+			var i = 0,
+				expanded = {},
+
+				// Assumes a single number if not a string
+				parts = typeof value === "string" ? value.split( " " ) : [ value ];
+
+			for ( ; i < 4; i++ ) {
+				expanded[ prefix + cssExpand[ i ] + suffix ] =
+					parts[ i ] || parts[ i - 2 ] || parts[ 0 ];
+			}
+
+			return expanded;
+		}
+	};
+
+	if ( !rmargin.test( prefix ) ) {
+		jQuery.cssHooks[ prefix + suffix ].set = setPositiveNumber;
+	}
+} );
+
+jQuery.fn.extend( {
+	css: function( name, value ) {
+		return access( this, function( elem, name, value ) {
+			var styles, len,
+				map = {},
+				i = 0;
+
+			if ( jQuery.isArray( name ) ) {
+				styles = getStyles( elem );
+				len = name.length;
+
+				for ( ; i < len; i++ ) {
+					map[ name[ i ] ] = jQuery.css( elem, name[ i ], false, styles );
+				}
+
+				return map;
+			}
+
+			return value !== undefined ?
+				jQuery.style( elem, name, value ) :
+				jQuery.css( elem, name );
+		}, name, value, arguments.length > 1 );
+	},
+	show: function() {
+		return showHide( this, true );
+	},
+	hide: function() {
+		return showHide( this );
+	},
+	toggle: function( state ) {
+		if ( typeof state === "boolean" ) {
+			return state ? this.show() : this.hide();
+		}
+
+		return this.each( function() {
+			if ( isHidden( this ) ) {
+				jQuery( this ).show();
+			} else {
+				jQuery( this ).hide();
+			}
+		} );
+	}
+} );
+
+
+function Tween( elem, options, prop, end, easing ) {
+	return new Tween.prototype.init( elem, options, prop, end, easing );
+}
+jQuery.Tween = Tween;
+
+Tween.prototype = {
+	constructor: Tween,
+	init: function( elem, options, prop, end, easing, unit ) {
+		this.elem = elem;
+		this.prop = prop;
+		this.easing = easing || jQuery.easing._default;
+		this.options = options;
+		this.start = this.now = this.cur();
+		this.end = end;
+		this.unit = unit || ( jQuery.cssNumber[ prop ] ? "" : "px" );
+	},
+	cur: function() {
+		var hooks = Tween.propHooks[ this.prop ];
+
+		return hooks && hooks.get ?
+			hooks.get( this ) :
+			Tween.propHooks._default.get( this );
+	},
+	run: function( percent ) {
+		var eased,
+			hooks = Tween.propHooks[ this.prop ];
+
+		if ( this.options.duration ) {
+			this.pos = eased = jQuery.easing[ this.easing ](
+				percent, this.options.duration * percent, 0, 1, this.options.duration
+			);
+		} else {
+			this.pos = eased = percent;
+		}
+		this.now = ( this.end - this.start ) * eased + this.start;
+
+		if ( this.options.step ) {
+			this.options.step.call( this.elem, this.now, this );
+		}
+
+		if ( hooks && hooks.set ) {
+			hooks.set( this );
+		} else {
+			Tween.propHooks._default.set( this );
+		}
+		return this;
+	}
+};
+
+Tween.prototype.init.prototype = Tween.prototype;
+
+Tween.propHooks = {
+	_default: {
+		get: function( tween ) {
+			var result;
+
+			// Use a property on the element directly when it is not a DOM element,
+			// or when there is no matching style property that exists.
+			if ( tween.elem.nodeType !== 1 ||
+				tween.elem[ tween.prop ] != null && tween.elem.style[ tween.prop ] == null ) {
+				return tween.elem[ tween.prop ];
+			}
+
+			// Passing an empty string as a 3rd parameter to .css will automatically
+			// attempt a parseFloat and fallback to a string if the parse fails.
+			// Simple values such as "10px" are parsed to Float;
+			// complex values such as "rotate(1rad)" are returned as-is.
+			result = jQuery.css( tween.elem, tween.prop, "" );
+
+			// Empty strings, null, undefined and "auto" are converted to 0.
+			return !result || result === "auto" ? 0 : result;
+		},
+		set: function( tween ) {
+
+			// Use step hook for back compat.
+			// Use cssHook if its there.
+			// Use .style if available and use plain properties where available.
+			if ( jQuery.fx.step[ tween.prop ] ) {
+				jQuery.fx.step[ tween.prop ]( tween );
+			} else if ( tween.elem.nodeType === 1 &&
+				( tween.elem.style[ jQuery.cssProps[ tween.prop ] ] != null ||
+					jQuery.cssHooks[ tween.prop ] ) ) {
+				jQuery.style( tween.elem, tween.prop, tween.now + tween.unit );
+			} else {
+				tween.elem[ tween.prop ] = tween.now;
+			}
+		}
+	}
+};
+
+// Support: IE9
+// Panic based approach to setting things on disconnected nodes
+Tween.propHooks.scrollTop = Tween.propHooks.scrollLeft = {
+	set: function( tween ) {
+		if ( tween.elem.nodeType && tween.elem.parentNode ) {
+			tween.elem[ tween.prop ] = tween.now;
+		}
+	}
+};
+
+jQuery.easing = {
+	linear: function( p ) {
+		return p;
+	},
+	swing: function( p ) {
+		return 0.5 - Math.cos( p * Math.PI ) / 2;
+	},
+	_default: "swing"
+};
+
+jQuery.fx = Tween.prototype.init;
+
+// Back Compat <1.8 extension point
+jQuery.fx.step = {};
+
+
+
+
+var
+	fxNow, timerId,
+	rfxtypes = /^(?:toggle|show|hide)$/,
+	rrun = /queueHooks$/;
+
+// Animations created synchronously will run synchronously
+function createFxNow() {
+	window.setTimeout( function() {
+		fxNow = undefined;
+	} );
+	return ( fxNow = jQuery.now() );
+}
+
+// Generate parameters to create a standard animation
+function genFx( type, includeWidth ) {
+	var which,
+		i = 0,
+		attrs = { height: type };
+
+	// If we include width, step value is 1 to do all cssExpand values,
+	// otherwise step value is 2 to skip over Left and Right
+	includeWidth = includeWidth ? 1 : 0;
+	for ( ; i < 4 ; i += 2 - includeWidth ) {
+		which = cssExpand[ i ];
+		attrs[ "margin" + which ] = attrs[ "padding" + which ] = type;
+	}
+
+	if ( includeWidth ) {
+		attrs.opacity = attrs.width = type;
+	}
+
+	return attrs;
+}
+
+function createTween( value, prop, animation ) {
+	var tween,
+		collection = ( Animation.tweeners[ prop ] || [] ).concat( Animation.tweeners[ "*" ] ),
+		index = 0,
+		length = collection.length;
+	for ( ; index < length; index++ ) {
+		if ( ( tween = collection[ index ].call( animation, prop, value ) ) ) {
+
+			// We're done with this property
+			return tween;
+		}
+	}
+}
+
+function defaultPrefilter( elem, props, opts ) {
+	/* jshint validthis: true */
+	var prop, value, toggle, tween, hooks, oldfire, display, checkDisplay,
+		anim = this,
+		orig = {},
+		style = elem.style,
+		hidden = elem.nodeType && isHidden( elem ),
+		dataShow = dataPriv.get( elem, "fxshow" );
+
+	// Handle queue: false promises
+	if ( !opts.queue ) {
+		hooks = jQuery._queueHooks( elem, "fx" );
+		if ( hooks.unqueued == null ) {
+			hooks.unqueued = 0;
+			oldfire = hooks.empty.fire;
+			hooks.empty.fire = function() {
+				if ( !hooks.unqueued ) {
+					oldfire();
+				}
+			};
+		}
+		hooks.unqueued++;
+
+		anim.always( function() {
+
+			// Ensure the complete handler is called before this completes
+			anim.always( function() {
+				hooks.unqueued--;
+				if ( !jQuery.queue( elem, "fx" ).length ) {
+					hooks.empty.fire();
+				}
+			} );
+		} );
+	}
+
+	// Height/width overflow pass
+	if ( elem.nodeType === 1 && ( "height" in props || "width" in props ) ) {
+
+		// Make sure that nothing sneaks out
+		// Record all 3 overflow attributes because IE9-10 do not
+		// change the overflow attribute when overflowX and
+		// overflowY are set to the same value
+		opts.overflow = [ style.overflow, style.overflowX, style.overflowY ];
+
+		// Set display property to inline-block for height/width
+		// animations on inline elements that are having width/height animated
+		display = jQuery.css( elem, "display" );
+
+		// Test default display if display is currently "none"
+		checkDisplay = display === "none" ?
+			dataPriv.get( elem, "olddisplay" ) || defaultDisplay( elem.nodeName ) : display;
+
+		if ( checkDisplay === "inline" && jQuery.css( elem, "float" ) === "none" ) {
+			style.display = "inline-block";
+		}
+	}
+
+	if ( opts.overflow ) {
+		style.overflow = "hidden";
+		anim.always( function() {
+			style.overflow = opts.overflow[ 0 ];
+			style.overflowX = opts.overflow[ 1 ];
+			style.overflowY = opts.overflow[ 2 ];
+		} );
+	}
+
+	// show/hide pass
+	for ( prop in props ) {
+		value = props[ prop ];
+		if ( rfxtypes.exec( value ) ) {
+			delete props[ prop ];
+			toggle = toggle || value === "toggle";
+			if ( value === ( hidden ? "hide" : "show" ) ) {
+
+				// If there is dataShow left over from a stopped hide or show
+				// and we are going to proceed with show, we should pretend to be hidden
+				if ( value === "show" && dataShow && dataShow[ prop ] !== undefined ) {
+					hidden = true;
+				} else {
+					continue;
+				}
+			}
+			orig[ prop ] = dataShow && dataShow[ prop ] || jQuery.style( elem, prop );
+
+		// Any non-fx value stops us from restoring the original display value
+		} else {
+			display = undefined;
+		}
+	}
+
+	if ( !jQuery.isEmptyObject( orig ) ) {
+		if ( dataShow ) {
+			if ( "hidden" in dataShow ) {
+				hidden = dataShow.hidden;
+			}
+		} else {
+			dataShow = dataPriv.access( elem, "fxshow", {} );
+		}
+
+		// Store state if its toggle - enables .stop().toggle() to "reverse"
+		if ( toggle ) {
+			dataShow.hidden = !hidden;
+		}
+		if ( hidden ) {
+			jQuery( elem ).show();
+		} else {
+			anim.done( function() {
+				jQuery( elem ).hide();
+			} );
+		}
+		anim.done( function() {
+			var prop;
+
+			dataPriv.remove( elem, "fxshow" );
+			for ( prop in orig ) {
+				jQuery.style( elem, prop, orig[ prop ] );
+			}
+		} );
+		for ( prop in orig ) {
+			tween = createTween( hidden ? dataShow[ prop ] : 0, prop, anim );
+
+			if ( !( prop in dataShow ) ) {
+				dataShow[ prop ] = tween.start;
+				if ( hidden ) {
+					tween.end = tween.start;
+					tween.start = prop === "width" || prop === "height" ? 1 : 0;
+				}
+			}
+		}
+
+	// If this is a noop like .hide().hide(), restore an overwritten display value
+	} else if ( ( display === "none" ? defaultDisplay( elem.nodeName ) : display ) === "inline" ) {
+		style.display = display;
+	}
+}
+
+function propFilter( props, specialEasing ) {
+	var index, name, easing, value, hooks;
+
+	// camelCase, specialEasing and expand cssHook pass
+	for ( index in props ) {
+		name = jQuery.camelCase( index );
+		easing = specialEasing[ name ];
+		value = props[ index ];
+		if ( jQuery.isArray( value ) ) {
+			easing = value[ 1 ];
+			value = props[ index ] = value[ 0 ];
+		}
+
+		if ( index !== name ) {
+			props[ name ] = value;
+			delete props[ index ];
+		}
+
+		hooks = jQuery.cssHooks[ name ];
+		if ( hooks && "expand" in hooks ) {
+			value = hooks.expand( value );
+			delete props[ name ];
+
+			// Not quite $.extend, this won't overwrite existing keys.
+			// Reusing 'index' because we have the correct "name"
+			for ( index in value ) {
+				if ( !( index in props ) ) {
+					props[ index ] = value[ index ];
+					specialEasing[ index ] = easing;
+				}
+			}
+		} else {
+			specialEasing[ name ] = easing;
+		}
+	}
+}
+
+function Animation( elem, properties, options ) {
+	var result,
+		stopped,
+		index = 0,
+		length = Animation.prefilters.length,
+		deferred = jQuery.Deferred().always( function() {
+
+			// Don't match elem in the :animated selector
+			delete tick.elem;
+		} ),
+		tick = function() {
+			if ( stopped ) {
+				return false;
+			}
+			var currentTime = fxNow || createFxNow(),
+				remaining = Math.max( 0, animation.startTime + animation.duration - currentTime ),
+
+				// Support: Android 2.3
+				// Archaic crash bug won't allow us to use `1 - ( 0.5 || 0 )` (#12497)
+				temp = remaining / animation.duration || 0,
+				percent = 1 - temp,
+				index = 0,
+				length = animation.tweens.length;
+
+			for ( ; index < length ; index++ ) {
+				animation.tweens[ index ].run( percent );
+			}
+
+			deferred.notifyWith( elem, [ animation, percent, remaining ] );
+
+			if ( percent < 1 && length ) {
+				return remaining;
+			} else {
+				deferred.resolveWith( elem, [ animation ] );
+				return false;
+			}
+		},
+		animation = deferred.promise( {
+			elem: elem,
+			props: jQuery.extend( {}, properties ),
+			opts: jQuery.extend( true, {
+				specialEasing: {},
+				easing: jQuery.easing._default
+			}, options ),
+			originalProperties: properties,
+			originalOptions: options,
+			startTime: fxNow || createFxNow(),
+			duration: options.duration,
+			tweens: [],
+			createTween: function( prop, end ) {
+				var tween = jQuery.Tween( elem, animation.opts, prop, end,
+						animation.opts.specialEasing[ prop ] || animation.opts.easing );
+				animation.tweens.push( tween );
+				return tween;
+			},
+			stop: function( gotoEnd ) {
+				var index = 0,
+
+					// If we are going to the end, we want to run all the tweens
+					// otherwise we skip this part
+					length = gotoEnd ? animation.tweens.length : 0;
+				if ( stopped ) {
+					return this;
+				}
+				stopped = true;
+				for ( ; index < length ; index++ ) {
+					animation.tweens[ index ].run( 1 );
+				}
+
+				// Resolve when we played the last frame; otherwise, reject
+				if ( gotoEnd ) {
+					deferred.notifyWith( elem, [ animation, 1, 0 ] );
+					deferred.resolveWith( elem, [ animation, gotoEnd ] );
+				} else {
+					deferred.rejectWith( elem, [ animation, gotoEnd ] );
+				}
+				return this;
+			}
+		} ),
+		props = animation.props;
+
+	propFilter( props, animation.opts.specialEasing );
+
+	for ( ; index < length ; index++ ) {
+		result = Animation.prefilters[ index ].call( animation, elem, props, animation.opts );
+		if ( result ) {
+			if ( jQuery.isFunction( result.stop ) ) {
+				jQuery._queueHooks( animation.elem, animation.opts.queue ).stop =
+					jQuery.proxy( result.stop, result );
+			}
+			return result;
+		}
+	}
+
+	jQuery.map( props, createTween, animation );
+
+	if ( jQuery.isFunction( animation.opts.start ) ) {
+		animation.opts.start.call( elem, animation );
+	}
+
+	jQuery.fx.timer(
+		jQuery.extend( tick, {
+			elem: elem,
+			anim: animation,
+			queue: animation.opts.queue
+		} )
+	);
+
+	// attach callbacks from options
+	return animation.progress( animation.opts.progress )
+		.done( animation.opts.done, animation.opts.complete )
+		.fail( animation.opts.fail )
+		.always( animation.opts.always );
+}
+
+jQuery.Animation = jQuery.extend( Animation, {
+	tweeners: {
+		"*": [ function( prop, value ) {
+			var tween = this.createTween( prop, value );
+			adjustCSS( tween.elem, prop, rcssNum.exec( value ), tween );
+			return tween;
+		} ]
+	},
+
+	tweener: function( props, callback ) {
+		if ( jQuery.isFunction( props ) ) {
+			callback = props;
+			props = [ "*" ];
+		} else {
+			props = props.match( rnotwhite );
+		}
+
+		var prop,
+			index = 0,
+			length = props.length;
+
+		for ( ; index < length ; index++ ) {
+			prop = props[ index ];
+			Animation.tweeners[ prop ] = Animation.tweeners[ prop ] || [];
+			Animation.tweeners[ prop ].unshift( callback );
+		}
+	},
+
+	prefilters: [ defaultPrefilter ],
+
+	prefilter: function( callback, prepend ) {
+		if ( prepend ) {
+			Animation.prefilters.unshift( callback );
+		} else {
+			Animation.prefilters.push( callback );
+		}
+	}
+} );
+
+jQuery.speed = function( speed, easing, fn ) {
+	var opt = speed && typeof speed === "object" ? jQuery.extend( {}, speed ) : {
+		complete: fn || !fn && easing ||
+			jQuery.isFunction( speed ) && speed,
+		duration: speed,
+		easing: fn && easing || easing && !jQuery.isFunction( easing ) && easing
+	};
+
+	opt.duration = jQuery.fx.off ? 0 : typeof opt.duration === "number" ?
+		opt.duration : opt.duration in jQuery.fx.speeds ?
+			jQuery.fx.speeds[ opt.duration ] : jQuery.fx.speeds._default;
+
+	// Normalize opt.queue - true/undefined/null -> "fx"
+	if ( opt.queue == null || opt.queue === true ) {
+		opt.queue = "fx";
+	}
+
+	// Queueing
+	opt.old = opt.complete;
+
+	opt.complete = function() {
+		if ( jQuery.isFunction( opt.old ) ) {
+			opt.old.call( this );
+		}
+
+		if ( opt.queue ) {
+			jQuery.dequeue( this, opt.queue );
+		}
+	};
+
+	return opt;
+};
+
+jQuery.fn.extend( {
+	fadeTo: function( speed, to, easing, callback ) {
+
+		// Show any hidden elements after setting opacity to 0
+		return this.filter( isHidden ).css( "opacity", 0 ).show()
+
+			// Animate to the value specified
+			.end().animate( { opacity: to }, speed, easing, callback );
+	},
+	animate: function( prop, speed, easing, callback ) {
+		var empty = jQuery.isEmptyObject( prop ),
+			optall = jQuery.speed( speed, easing, callback ),
+			doAnimation = function() {
+
+				// Operate on a copy of prop so per-property easing won't be lost
+				var anim = Animation( this, jQuery.extend( {}, prop ), optall );
+
+				// Empty animations, or finishing resolves immediately
+				if ( empty || dataPriv.get( this, "finish" ) ) {
+					anim.stop( true );
+				}
+			};
+			doAnimation.finish = doAnimation;
+
+		return empty || optall.queue === false ?
+			this.each( doAnimation ) :
+			this.queue( optall.queue, doAnimation );
+	},
+	stop: function( type, clearQueue, gotoEnd ) {
+		var stopQueue = function( hooks ) {
+			var stop = hooks.stop;
+			delete hooks.stop;
+			stop( gotoEnd );
+		};
+
+		if ( typeof type !== "string" ) {
+			gotoEnd = clearQueue;
+			clearQueue = type;
+			type = undefined;
+		}
+		if ( clearQueue && type !== false ) {
+			this.queue( type || "fx", [] );
+		}
+
+		return this.each( function() {
+			var dequeue = true,
+				index = type != null && type + "queueHooks",
+				timers = jQuery.timers,
+				data = dataPriv.get( this );
+
+			if ( index ) {
+				if ( data[ index ] && data[ index ].stop ) {
+					stopQueue( data[ index ] );
+				}
+			} else {
+				for ( index in data ) {
+					if ( data[ index ] && data[ index ].stop && rrun.test( index ) ) {
+						stopQueue( data[ index ] );
+					}
+				}
+			}
+
+			for ( index = timers.length; index--; ) {
+				if ( timers[ index ].elem === this &&
+					( type == null || timers[ index ].queue === type ) ) {
+
+					timers[ index ].anim.stop( gotoEnd );
+					dequeue = false;
+					timers.splice( index, 1 );
+				}
+			}
+
+			// Start the next in the queue if the last step wasn't forced.
+			// Timers currently will call their complete callbacks, which
+			// will dequeue but only if they were gotoEnd.
+			if ( dequeue || !gotoEnd ) {
+				jQuery.dequeue( this, type );
+			}
+		} );
+	},
+	finish: function( type ) {
+		if ( type !== false ) {
+			type = type || "fx";
+		}
+		return this.each( function() {
+			var index,
+				data = dataPriv.get( this ),
+				queue = data[ type + "queue" ],
+				hooks = data[ type + "queueHooks" ],
+				timers = jQuery.timers,
+				length = queue ? queue.length : 0;
+
+			// Enable finishing flag on private data
+			data.finish = true;
+
+			// Empty the queue first
+			jQuery.queue( this, type, [] );
+
+			if ( hooks && hooks.stop ) {
+				hooks.stop.call( this, true );
+			}
+
+			// Look for any active animations, and finish them
+			for ( index = timers.length; index--; ) {
+				if ( timers[ index ].elem === this && timers[ index ].queue === type ) {
+					timers[ index ].anim.stop( true );
+					timers.splice( index, 1 );
+				}
+			}
+
+			// Look for any animations in the old queue and finish them
+			for ( index = 0; index < length; index++ ) {
+				if ( queue[ index ] && queue[ index ].finish ) {
+					queue[ index ].finish.call( this );
+				}
+			}
+
+			// Turn off finishing flag
+			delete data.finish;
+		} );
+	}
+} );
+
+jQuery.each( [ "toggle", "show", "hide" ], function( i, name ) {
+	var cssFn = jQuery.fn[ name ];
+	jQuery.fn[ name ] = function( speed, easing, callback ) {
+		return speed == null || typeof speed === "boolean" ?
+			cssFn.apply( this, arguments ) :
+			this.animate( genFx( name, true ), speed, easing, callback );
+	};
+} );
+
+// Generate shortcuts for custom animations
+jQuery.each( {
+	slideDown: genFx( "show" ),
+	slideUp: genFx( "hide" ),
+	slideToggle: genFx( "toggle" ),
+	fadeIn: { opacity: "show" },
+	fadeOut: { opacity: "hide" },
+	fadeToggle: { opacity: "toggle" }
+}, function( name, props ) {
+	jQuery.fn[ name ] = function( speed, easing, callback ) {
+		return this.animate( props, speed, easing, callback );
+	};
+} );
+
+jQuery.timers = [];
+jQuery.fx.tick = function() {
+	var timer,
+		i = 0,
+		timers = jQuery.timers;
+
+	fxNow = jQuery.now();
+
+	for ( ; i < timers.length; i++ ) {
+		timer = timers[ i ];
+
+		// Checks the timer has not already been removed
+		if ( !timer() && timers[ i ] === timer ) {
+			timers.splice( i--, 1 );
+		}
+	}
+
+	if ( !timers.length ) {
+		jQuery.fx.stop();
+	}
+	fxNow = undefined;
+};
+
+jQuery.fx.timer = function( timer ) {
+	jQuery.timers.push( timer );
+	if ( timer() ) {
+		jQuery.fx.start();
+	} else {
+		jQuery.timers.pop();
+	}
+};
+
+jQuery.fx.interval = 13;
+jQuery.fx.start = function() {
+	if ( !timerId ) {
+		timerId = window.setInterval( jQuery.fx.tick, jQuery.fx.interval );
+	}
+};
+
+jQuery.fx.stop = function() {
+	window.clearInterval( timerId );
+
+	timerId = null;
+};
+
+jQuery.fx.speeds = {
+	slow: 600,
+	fast: 200,
+
+	// Default speed
+	_default: 400
+};
+
+
+// Based off of the plugin by Clint Helfers, with permission.
+// http://web.archive.org/web/20100324014747/http://blindsignals.com/index.php/2009/07/jquery-delay/
+jQuery.fn.delay = function( time, type ) {
+	time = jQuery.fx ? jQuery.fx.speeds[ time ] || time : time;
+	type = type || "fx";
+
+	return this.queue( type, function( next, hooks ) {
+		var timeout = window.setTimeout( next, time );
+		hooks.stop = function() {
+			window.clearTimeout( timeout );
+		};
+	} );
+};
+
+
+( function() {
+	var input = document.createElement( "input" ),
+		select = document.createElement( "select" ),
+		opt = select.appendChild( document.createElement( "option" ) );
+
+	input.type = "checkbox";
+
+	// Support: iOS<=5.1, Android<=4.2+
+	// Default value for a checkbox should be "on"
+	support.checkOn = input.value !== "";
+
+	// Support: IE<=11+
+	// Must access selectedIndex to make default options select
+	support.optSelected = opt.selected;
+
+	// Support: Android<=2.3
+	// Options inside disabled selects are incorrectly marked as disabled
+	select.disabled = true;
+	support.optDisabled = !opt.disabled;
+
+	// Support: IE<=11+
+	// An input loses its value after becoming a radio
+	input = document.createElement( "input" );
+	input.value = "t";
+	input.type = "radio";
+	support.radioValue = input.value === "t";
+} )();
+
+
+var boolHook,
+	attrHandle = jQuery.expr.attrHandle;
+
+jQuery.fn.extend( {
+	attr: function( name, value ) {
+		return access( this, jQuery.attr, name, value, arguments.length > 1 );
+	},
+
+	removeAttr: function( name ) {
+		return this.each( function() {
+			jQuery.removeAttr( this, name );
+		} );
+	}
+} );
+
+jQuery.extend( {
+	attr: function( elem, name, value ) {
+		var ret, hooks,
+			nType = elem.nodeType;
+
+		// Don't get/set attributes on text, comment and attribute nodes
+		if ( nType === 3 || nType === 8 || nType === 2 ) {
+			return;
+		}
+
+		// Fallback to prop when attributes are not supported
+		if ( typeof elem.getAttribute === "undefined" ) {
+			return jQuery.prop( elem, name, value );
+		}
+
+		// All attributes are lowercase
+		// Grab necessary hook if one is defined
+		if ( nType !== 1 || !jQuery.isXMLDoc( elem ) ) {
+			name = name.toLowerCase();
+			hooks = jQuery.attrHooks[ name ] ||
+				( jQuery.expr.match.bool.test( name ) ? boolHook : undefined );
+		}
+
+		if ( value !== undefined ) {
+			if ( value === null ) {
+				jQuery.removeAttr( elem, name );
+				return;
+			}
+
+			if ( hooks && "set" in hooks &&
+				( ret = hooks.set( elem, value, name ) ) !== undefined ) {
+				return ret;
+			}
+
+			elem.setAttribute( name, value + "" );
+			return value;
+		}
+
+		if ( hooks && "get" in hooks && ( ret = hooks.get( elem, name ) ) !== null ) {
+			return ret;
+		}
+
+		ret = jQuery.find.attr( elem, name );
+
+		// Non-existent attributes return null, we normalize to undefined
+		return ret == null ? undefined : ret;
+	},
+
+	attrHooks: {
+		type: {
+			set: function( elem, value ) {
+				if ( !support.radioValue && value === "radio" &&
+					jQuery.nodeName( elem, "input" ) ) {
+					var val = elem.value;
+					elem.setAttribute( "type", value );
+					if ( val ) {
+						elem.value = val;
+					}
+					return value;
+				}
+			}
+		}
+	},
+
+	removeAttr: function( elem, value ) {
+		var name, propName,
+			i = 0,
+			attrNames = value && value.match( rnotwhite );
+
+		if ( attrNames && elem.nodeType === 1 ) {
+			while ( ( name = attrNames[ i++ ] ) ) {
+				propName = jQuery.propFix[ name ] || name;
+
+				// Boolean attributes get special treatment (#10870)
+				if ( jQuery.expr.match.bool.test( name ) ) {
+
+					// Set corresponding property to false
+					elem[ propName ] = false;
+				}
+
+				elem.removeAttribute( name );
+			}
+		}
+	}
+} );
+
+// Hooks for boolean attributes
+boolHook = {
+	set: function( elem, value, name ) {
+		if ( value === false ) {
+
+			// Remove boolean attributes when set to false
+			jQuery.removeAttr( elem, name );
+		} else {
+			elem.setAttribute( name, name );
+		}
+		return name;
+	}
+};
+jQuery.each( jQuery.expr.match.bool.source.match( /\w+/g ), function( i, name ) {
+	var getter = attrHandle[ name ] || jQuery.find.attr;
+
+	attrHandle[ name ] = function( elem, name, isXML ) {
+		var ret, handle;
+		if ( !isXML ) {
+
+			// Avoid an infinite loop by temporarily removing this function from the getter
+			handle = attrHandle[ name ];
+			attrHandle[ name ] = ret;
+			ret = getter( elem, name, isXML ) != null ?
+				name.toLowerCase() :
+				null;
+			attrHandle[ name ] = handle;
+		}
+		return ret;
+	};
+} );
+
+
+
+
+var rfocusable = /^(?:input|select|textarea|button)$/i,
+	rclickable = /^(?:a|area)$/i;
+
+jQuery.fn.extend( {
+	prop: function( name, value ) {
+		return access( this, jQuery.prop, name, value, arguments.length > 1 );
+	},
+
+	removeProp: function( name ) {
+		return this.each( function() {
+			delete this[ jQuery.propFix[ name ] || name ];
+		} );
+	}
+} );
+
+jQuery.extend( {
+	prop: function( elem, name, value ) {
+		var ret, hooks,
+			nType = elem.nodeType;
+
+		// Don't get/set properties on text, comment and attribute nodes
+		if ( nType === 3 || nType === 8 || nType === 2 ) {
+			return;
+		}
+
+		if ( nType !== 1 || !jQuery.isXMLDoc( elem ) ) {
+
+			// Fix name and attach hooks
+			name = jQuery.propFix[ name ] || name;
+			hooks = jQuery.propHooks[ name ];
+		}
+
+		if ( value !== undefined ) {
+			if ( hooks && "set" in hooks &&
+				( ret = hooks.set( elem, value, name ) ) !== undefined ) {
+				return ret;
+			}
+
+			return ( elem[ name ] = value );
+		}
+
+		if ( hooks && "get" in hooks && ( ret = hooks.get( elem, name ) ) !== null ) {
+			return ret;
+		}
+
+		return elem[ name ];
+	},
+
+	propHooks: {
+		tabIndex: {
+			get: function( elem ) {
+
+				// elem.tabIndex doesn't always return the
+				// correct value when it hasn't been explicitly set
+				// http://fluidproject.org/blog/2008/01/09/getting-setting-and-removing-tabindex-values-with-javascript/
+				// Use proper attribute retrieval(#12072)
+				var tabindex = jQuery.find.attr( elem, "tabindex" );
+
+				return tabindex ?
+					parseInt( tabindex, 10 ) :
+					rfocusable.test( elem.nodeName ) ||
+						rclickable.test( elem.nodeName ) && elem.href ?
+							0 :
+							-1;
+			}
+		}
+	},
+
+	propFix: {
+		"for": "htmlFor",
+		"class": "className"
+	}
+} );
+
+if ( !support.optSelected ) {
+	jQuery.propHooks.selected = {
+		get: function( elem ) {
+			var parent = elem.parentNode;
+			if ( parent && parent.parentNode ) {
+				parent.parentNode.selectedIndex;
+			}
+			return null;
+		}
+	};
+}
+
+jQuery.each( [
+	"tabIndex",
+	"readOnly",
+	"maxLength",
+	"cellSpacing",
+	"cellPadding",
+	"rowSpan",
+	"colSpan",
+	"useMap",
+	"frameBorder",
+	"contentEditable"
+], function() {
+	jQuery.propFix[ this.toLowerCase() ] = this;
+} );
+
+
+
+
+var rclass = /[\t\r\n\f]/g;
+
+function getClass( elem ) {
+	return elem.getAttribute && elem.getAttribute( "class" ) || "";
+}
+
+jQuery.fn.extend( {
+	addClass: function( value ) {
+		var classes, elem, cur, curValue, clazz, j, finalValue,
+			i = 0;
+
+		if ( jQuery.isFunction( value ) ) {
+			return this.each( function( j ) {
+				jQuery( this ).addClass( value.call( this, j, getClass( this ) ) );
+			} );
+		}
+
+		if ( typeof value === "string" && value ) {
+			classes = value.match( rnotwhite ) || [];
+
+			while ( ( elem = this[ i++ ] ) ) {
+				curValue = getClass( elem );
+				cur = elem.nodeType === 1 &&
+					( " " + curValue + " " ).replace( rclass, " " );
+
+				if ( cur ) {
+					j = 0;
+					while ( ( clazz = classes[ j++ ] ) ) {
+						if ( cur.indexOf( " " + clazz + " " ) < 0 ) {
+							cur += clazz + " ";
+						}
+					}
+
+					// Only assign if different to avoid unneeded rendering.
+					finalValue = jQuery.trim( cur );
+					if ( curValue !== finalValue ) {
+						elem.setAttribute( "class", finalValue );
+					}
+				}
+			}
+		}
+
+		return this;
+	},
+
+	removeClass: function( value ) {
+		var classes, elem, cur, curValue, clazz, j, finalValue,
+			i = 0;
+
+		if ( jQuery.isFunction( value ) ) {
+			return this.each( function( j ) {
+				jQuery( this ).removeClass( value.call( this, j, getClass( this ) ) );
+			} );
+		}
+
+		if ( !arguments.length ) {
+			return this.attr( "class", "" );
+		}
+
+		if ( typeof value === "string" && value ) {
+			classes = value.match( rnotwhite ) || [];
+
+			while ( ( elem = this[ i++ ] ) ) {
+				curValue = getClass( elem );
+
+				// This expression is here for better compressibility (see addClass)
+				cur = elem.nodeType === 1 &&
+					( " " + curValue + " " ).replace( rclass, " " );
+
+				if ( cur ) {
+					j = 0;
+					while ( ( clazz = classes[ j++ ] ) ) {
+
+						// Remove *all* instances
+						while ( cur.indexOf( " " + clazz + " " ) > -1 ) {
+							cur = cur.replace( " " + clazz + " ", " " );
+						}
+					}
+
+					// Only assign if different to avoid unneeded rendering.
+					finalValue = jQuery.trim( cur );
+					if ( curValue !== finalValue ) {
+						elem.setAttribute( "class", finalValue );
+					}
+				}
+			}
+		}
+
+		return this;
+	},
+
+	toggleClass: function( value, stateVal ) {
+		var type = typeof value;
+
+		if ( typeof stateVal === "boolean" && type === "string" ) {
+			return stateVal ? this.addClass( value ) : this.removeClass( value );
+		}
+
+		if ( jQuery.isFunction( value ) ) {
+			return this.each( function( i ) {
+				jQuery( this ).toggleClass(
+					value.call( this, i, getClass( this ), stateVal ),
+					stateVal
+				);
+			} );
+		}
+
+		return this.each( function() {
+			var className, i, self, classNames;
+
+			if ( type === "string" ) {
+
+				// Toggle individual class names
+				i = 0;
+				self = jQuery( this );
+				classNames = value.match( rnotwhite ) || [];
+
+				while ( ( className = classNames[ i++ ] ) ) {
+
+					// Check each className given, space separated list
+					if ( self.hasClass( className ) ) {
+						self.removeClass( className );
+					} else {
+						self.addClass( className );
+					}
+				}
+
+			// Toggle whole class name
+			} else if ( value === undefined || type === "boolean" ) {
+				className = getClass( this );
+				if ( className ) {
+
+					// Store className if set
+					dataPriv.set( this, "__className__", className );
+				}
+
+				// If the element has a class name or if we're passed `false`,
+				// then remove the whole classname (if there was one, the above saved it).
+				// Otherwise bring back whatever was previously saved (if anything),
+				// falling back to the empty string if nothing was stored.
+				if ( this.setAttribute ) {
+					this.setAttribute( "class",
+						className || value === false ?
+						"" :
+						dataPriv.get( this, "__className__" ) || ""
+					);
+				}
+			}
+		} );
+	},
+
+	hasClass: function( selector ) {
+		var className, elem,
+			i = 0;
+
+		className = " " + selector + " ";
+		while ( ( elem = this[ i++ ] ) ) {
+			if ( elem.nodeType === 1 &&
+				( " " + getClass( elem ) + " " ).replace( rclass, " " )
+					.indexOf( className ) > -1
+			) {
+				return true;
+			}
+		}
+
+		return false;
+	}
+} );
+
+
+
+
+var rreturn = /\r/g;
+
+jQuery.fn.extend( {
+	val: function( value ) {
+		var hooks, ret, isFunction,
+			elem = this[ 0 ];
+
+		if ( !arguments.length ) {
+			if ( elem ) {
+				hooks = jQuery.valHooks[ elem.type ] ||
+					jQuery.valHooks[ elem.nodeName.toLowerCase() ];
+
+				if ( hooks &&
+					"get" in hooks &&
+					( ret = hooks.get( elem, "value" ) ) !== undefined
+				) {
+					return ret;
+				}
+
+				ret = elem.value;
+
+				return typeof ret === "string" ?
+
+					// Handle most common string cases
+					ret.replace( rreturn, "" ) :
+
+					// Handle cases where value is null/undef or number
+					ret == null ? "" : ret;
+			}
+
+			return;
+		}
+
+		isFunction = jQuery.isFunction( value );
+
+		return this.each( function( i ) {
+			var val;
+
+			if ( this.nodeType !== 1 ) {
+				return;
+			}
+
+			if ( isFunction ) {
+				val = value.call( this, i, jQuery( this ).val() );
+			} else {
+				val = value;
+			}
+
+			// Treat null/undefined as ""; convert numbers to string
+			if ( val == null ) {
+				val = "";
+
+			} else if ( typeof val === "number" ) {
+				val += "";
+
+			} else if ( jQuery.isArray( val ) ) {
+				val = jQuery.map( val, function( value ) {
+					return value == null ? "" : value + "";
+				} );
+			}
+
+			hooks = jQuery.valHooks[ this.type ] || jQuery.valHooks[ this.nodeName.toLowerCase() ];
+
+			// If set returns undefined, fall back to normal setting
+			if ( !hooks || !( "set" in hooks ) || hooks.set( this, val, "value" ) === undefined ) {
+				this.value = val;
+			}
+		} );
+	}
+} );
+
+jQuery.extend( {
+	valHooks: {
+		option: {
+			get: function( elem ) {
+
+				// Support: IE<11
+				// option.value not trimmed (#14858)
+				return jQuery.trim( elem.value );
+			}
+		},
+		select: {
+			get: function( elem ) {
+				var value, option,
+					options = elem.options,
+					index = elem.selectedIndex,
+					one = elem.type === "select-one" || index < 0,
+					values = one ? null : [],
+					max = one ? index + 1 : options.length,
+					i = index < 0 ?
+						max :
+						one ? index : 0;
+
+				// Loop through all the selected options
+				for ( ; i < max; i++ ) {
+					option = options[ i ];
+
+					// IE8-9 doesn't update selected after form reset (#2551)
+					if ( ( option.selected || i === index ) &&
+
+							// Don't return options that are disabled or in a disabled optgroup
+							( support.optDisabled ?
+								!option.disabled : option.getAttribute( "disabled" ) === null ) &&
+							( !option.parentNode.disabled ||
+								!jQuery.nodeName( option.parentNode, "optgroup" ) ) ) {
+
+						// Get the specific value for the option
+						value = jQuery( option ).val();
+
+						// We don't need an array for one selects
+						if ( one ) {
+							return value;
+						}
+
+						// Multi-Selects return an array
+						values.push( value );
+					}
+				}
+
+				return values;
+			},
+
+			set: function( elem, value ) {
+				var optionSet, option,
+					options = elem.options,
+					values = jQuery.makeArray( value ),
+					i = options.length;
+
+				while ( i-- ) {
+					option = options[ i ];
+					if ( option.selected =
+							jQuery.inArray( jQuery.valHooks.option.get( option ), values ) > -1
+					) {
+						optionSet = true;
+					}
+				}
+
+				// Force browsers to behave consistently when non-matching value is set
+				if ( !optionSet ) {
+					elem.selectedIndex = -1;
+				}
+				return values;
+			}
+		}
+	}
+} );
+
+// Radios and checkboxes getter/setter
+jQuery.each( [ "radio", "checkbox" ], function() {
+	jQuery.valHooks[ this ] = {
+		set: function( elem, value ) {
+			if ( jQuery.isArray( value ) ) {
+				return ( elem.checked = jQuery.inArray( jQuery( elem ).val(), value ) > -1 );
+			}
+		}
+	};
+	if ( !support.checkOn ) {
+		jQuery.valHooks[ this ].get = function( elem ) {
+			return elem.getAttribute( "value" ) === null ? "on" : elem.value;
+		};
+	}
+} );
+
+
+
+
+// Return jQuery for attributes-only inclusion
+
+
+var rfocusMorph = /^(?:focusinfocus|focusoutblur)$/;
+
+jQuery.extend( jQuery.event, {
+
+	trigger: function( event, data, elem, onlyHandlers ) {
+
+		var i, cur, tmp, bubbleType, ontype, handle, special,
+			eventPath = [ elem || document ],
+			type = hasOwn.call( event, "type" ) ? event.type : event,
+			namespaces = hasOwn.call( event, "namespace" ) ? event.namespace.split( "." ) : [];
+
+		cur = tmp = elem = elem || document;
+
+		// Don't do events on text and comment nodes
+		if ( elem.nodeType === 3 || elem.nodeType === 8 ) {
+			return;
+		}
+
+		// focus/blur morphs to focusin/out; ensure we're not firing them right now
+		if ( rfocusMorph.test( type + jQuery.event.triggered ) ) {
+			return;
+		}
+
+		if ( type.indexOf( "." ) > -1 ) {
+
+			// Namespaced trigger; create a regexp to match event type in handle()
+			namespaces = type.split( "." );
+			type = namespaces.shift();
+			namespaces.sort();
+		}
+		ontype = type.indexOf( ":" ) < 0 && "on" + type;
+
+		// Caller can pass in a jQuery.Event object, Object, or just an event type string
+		event = event[ jQuery.expando ] ?
+			event :
+			new jQuery.Event( type, typeof event === "object" && event );
+
+		// Trigger bitmask: & 1 for native handlers; & 2 for jQuery (always true)
+		event.isTrigger = onlyHandlers ? 2 : 3;
+		event.namespace = namespaces.join( "." );
+		event.rnamespace = event.namespace ?
+			new RegExp( "(^|\\.)" + namespaces.join( "\\.(?:.*\\.|)" ) + "(\\.|$)" ) :
+			null;
+
+		// Clean up the event in case it is being reused
+		event.result = undefined;
+		if ( !event.target ) {
+			event.target = elem;
+		}
+
+		// Clone any incoming data and prepend the event, creating the handler arg list
+		data = data == null ?
+			[ event ] :
+			jQuery.makeArray( data, [ event ] );
+
+		// Allow special events to draw outside the lines
+		special = jQuery.event.special[ type ] || {};
+		if ( !onlyHandlers && special.trigger && special.trigger.apply( elem, data ) === false ) {
+			return;
+		}
+
+		// Determine event propagation path in advance, per W3C events spec (#9951)
+		// Bubble up to document, then to window; watch for a global ownerDocument var (#9724)
+		if ( !onlyHandlers && !special.noBubble && !jQuery.isWindow( elem ) ) {
+
+			bubbleType = special.delegateType || type;
+			if ( !rfocusMorph.test( bubbleType + type ) ) {
+				cur = cur.parentNode;
+			}
+			for ( ; cur; cur = cur.parentNode ) {
+				eventPath.push( cur );
+				tmp = cur;
+			}
+
+			// Only add window if we got to document (e.g., not plain obj or detached DOM)
+			if ( tmp === ( elem.ownerDocument || document ) ) {
+				eventPath.push( tmp.defaultView || tmp.parentWindow || window );
+			}
+		}
+
+		// Fire handlers on the event path
+		i = 0;
+		while ( ( cur = eventPath[ i++ ] ) && !event.isPropagationStopped() ) {
+
+			event.type = i > 1 ?
+				bubbleType :
+				special.bindType || type;
+
+			// jQuery handler
+			handle = ( dataPriv.get( cur, "events" ) || {} )[ event.type ] &&
+				dataPriv.get( cur, "handle" );
+			if ( handle ) {
+				handle.apply( cur, data );
+			}
+
+			// Native handler
+			handle = ontype && cur[ ontype ];
+			if ( handle && handle.apply && acceptData( cur ) ) {
+				event.result = handle.apply( cur, data );
+				if ( event.result === false ) {
+					event.preventDefault();
+				}
+			}
+		}
+		event.type = type;
+
+		// If nobody prevented the default action, do it now
+		if ( !onlyHandlers && !event.isDefaultPrevented() ) {
+
+			if ( ( !special._default ||
+				special._default.apply( eventPath.pop(), data ) === false ) &&
+				acceptData( elem ) ) {
+
+				// Call a native DOM method on the target with the same name name as the event.
+				// Don't do default actions on window, that's where global variables be (#6170)
+				if ( ontype && jQuery.isFunction( elem[ type ] ) && !jQuery.isWindow( elem ) ) {
+
+					// Don't re-trigger an onFOO event when we call its FOO() method
+					tmp = elem[ ontype ];
+
+					if ( tmp ) {
+						elem[ ontype ] = null;
+					}
+
+					// Prevent re-triggering of the same event, since we already bubbled it above
+					jQuery.event.triggered = type;
+					elem[ type ]();
+					jQuery.event.triggered = undefined;
+
+					if ( tmp ) {
+						elem[ ontype ] = tmp;
+					}
+				}
+			}
+		}
+
+		return event.result;
+	},
+
+	// Piggyback on a donor event to simulate a different one
+	simulate: function( type, elem, event ) {
+		var e = jQuery.extend(
+			new jQuery.Event(),
+			event,
+			{
+				type: type,
+				isSimulated: true
+
+				// Previously, `originalEvent: {}` was set here, so stopPropagation call
+				// would not be triggered on donor event, since in our own
+				// jQuery.event.stopPropagation function we had a check for existence of
+				// originalEvent.stopPropagation method, so, consequently it would be a noop.
+				//
+				// But now, this "simulate" function is used only for events
+				// for which stopPropagation() is noop, so there is no need for that anymore.
+				//
+				// For the compat branch though, guard for "click" and "submit"
+				// events is still used, but was moved to jQuery.event.stopPropagation function
+				// because `originalEvent` should point to the original event for the constancy
+				// with other events and for more focused logic
+			}
+		);
+
+		jQuery.event.trigger( e, null, elem );
+
+		if ( e.isDefaultPrevented() ) {
+			event.preventDefault();
+		}
+	}
+
+} );
+
+jQuery.fn.extend( {
+
+	trigger: function( type, data ) {
+		return this.each( function() {
+			jQuery.event.trigger( type, data, this );
+		} );
+	},
+	triggerHandler: function( type, data ) {
+		var elem = this[ 0 ];
+		if ( elem ) {
+			return jQuery.event.trigger( type, data, elem, true );
+		}
+	}
+} );
+
+
+jQuery.each( ( "blur focus focusin focusout load resize scroll unload click dblclick " +
+	"mousedown mouseup mousemove mouseover mouseout mouseenter mouseleave " +
+	"change select submit keydown keypress keyup error contextmenu" ).split( " " ),
+	function( i, name ) {
+
+	// Handle event binding
+	jQuery.fn[ name ] = function( data, fn ) {
+		return arguments.length > 0 ?
+			this.on( name, null, data, fn ) :
+			this.trigger( name );
+	};
+} );
+
+jQuery.fn.extend( {
+	hover: function( fnOver, fnOut ) {
+		return this.mouseenter( fnOver ).mouseleave( fnOut || fnOver );
+	}
+} );
+
+
+
+
+support.focusin = "onfocusin" in window;
+
+
+// Support: Firefox
+// Firefox doesn't have focus(in | out) events
+// Related ticket - https://bugzilla.mozilla.org/show_bug.cgi?id=687787
+//
+// Support: Chrome, Safari
+// focus(in | out) events fire after focus & blur events,
+// which is spec violation - http://www.w3.org/TR/DOM-Level-3-Events/#events-focusevent-event-order
+// Related ticket - https://code.google.com/p/chromium/issues/detail?id=449857
+if ( !support.focusin ) {
+	jQuery.each( { focus: "focusin", blur: "focusout" }, function( orig, fix ) {
+
+		// Attach a single capturing handler on the document while someone wants focusin/focusout
+		var handler = function( event ) {
+			jQuery.event.simulate( fix, event.target, jQuery.event.fix( event ) );
+		};
+
+		jQuery.event.special[ fix ] = {
+			setup: function() {
+				var doc = this.ownerDocument || this,
+					attaches = dataPriv.access( doc, fix );
+
+				if ( !attaches ) {
+					doc.addEventListener( orig, handler, true );
+				}
+				dataPriv.access( doc, fix, ( attaches || 0 ) + 1 );
+			},
+			teardown: function() {
+				var doc = this.ownerDocument || this,
+					attaches = dataPriv.access( doc, fix ) - 1;
+
+				if ( !attaches ) {
+					doc.removeEventListener( orig, handler, true );
+					dataPriv.remove( doc, fix );
+
+				} else {
+					dataPriv.access( doc, fix, attaches );
+				}
+			}
+		};
+	} );
+}
+var location = window.location;
+
+var nonce = jQuery.now();
+
+var rquery = ( /\?/ );
+
+
+
+// Support: Android 2.3
+// Workaround failure to string-cast null input
+jQuery.parseJSON = function( data ) {
+	return JSON.parse( data + "" );
+};
+
+
+// Cross-browser xml parsing
+jQuery.parseXML = function( data ) {
+	var xml;
+	if ( !data || typeof data !== "string" ) {
+		return null;
+	}
+
+	// Support: IE9
+	try {
+		xml = ( new window.DOMParser() ).parseFromString( data, "text/xml" );
+	} catch ( e ) {
+		xml = undefined;
+	}
+
+	if ( !xml || xml.getElementsByTagName( "parsererror" ).length ) {
+		jQuery.error( "Invalid XML: " + data );
+	}
+	return xml;
+};
+
+
+var
+	rhash = /#.*$/,
+	rts = /([?&])_=[^&]*/,
+	rheaders = /^(.*?):[ \t]*([^\r\n]*)$/mg,
+
+	// #7653, #8125, #8152: local protocol detection
+	rlocalProtocol = /^(?:about|app|app-storage|.+-extension|file|res|widget):$/,
+	rnoContent = /^(?:GET|HEAD)$/,
+	rprotocol = /^\/\//,
+
+	/* Prefilters
+	 * 1) They are useful to introduce custom dataTypes (see ajax/jsonp.js for an example)
+	 * 2) These are called:
+	 *    - BEFORE asking for a transport
+	 *    - AFTER param serialization (s.data is a string if s.processData is true)
+	 * 3) key is the dataType
+	 * 4) the catchall symbol "*" can be used
+	 * 5) execution will start with transport dataType and THEN continue down to "*" if needed
+	 */
+	prefilters = {},
+
+	/* Transports bindings
+	 * 1) key is the dataType
+	 * 2) the catchall symbol "*" can be used
+	 * 3) selection will start with transport dataType and THEN go to "*" if needed
+	 */
+	transports = {},
+
+	// Avoid comment-prolog char sequence (#10098); must appease lint and evade compression
+	allTypes = "*/".concat( "*" ),
+
+	// Anchor tag for parsing the document origin
+	originAnchor = document.createElement( "a" );
+	originAnchor.href = location.href;
+
+// Base "constructor" for jQuery.ajaxPrefilter and jQuery.ajaxTransport
+function addToPrefiltersOrTransports( structure ) {
+
+	// dataTypeExpression is optional and defaults to "*"
+	return function( dataTypeExpression, func ) {
+
+		if ( typeof dataTypeExpression !== "string" ) {
+			func = dataTypeExpression;
+			dataTypeExpression = "*";
+		}
+
+		var dataType,
+			i = 0,
+			dataTypes = dataTypeExpression.toLowerCase().match( rnotwhite ) || [];
+
+		if ( jQuery.isFunction( func ) ) {
+
+			// For each dataType in the dataTypeExpression
+			while ( ( dataType = dataTypes[ i++ ] ) ) {
+
+				// Prepend if requested
+				if ( dataType[ 0 ] === "+" ) {
+					dataType = dataType.slice( 1 ) || "*";
+					( structure[ dataType ] = structure[ dataType ] || [] ).unshift( func );
+
+				// Otherwise append
+				} else {
+					( structure[ dataType ] = structure[ dataType ] || [] ).push( func );
+				}
+			}
+		}
+	};
+}
+
+// Base inspection function for prefilters and transports
+function inspectPrefiltersOrTransports( structure, options, originalOptions, jqXHR ) {
+
+	var inspected = {},
+		seekingTransport = ( structure === transports );
+
+	function inspect( dataType ) {
+		var selected;
+		inspected[ dataType ] = true;
+		jQuery.each( structure[ dataType ] || [], function( _, prefilterOrFactory ) {
+			var dataTypeOrTransport = prefilterOrFactory( options, originalOptions, jqXHR );
+			if ( typeof dataTypeOrTransport === "string" &&
+				!seekingTransport && !inspected[ dataTypeOrTransport ] ) {
+
+				options.dataTypes.unshift( dataTypeOrTransport );
+				inspect( dataTypeOrTransport );
+				return false;
+			} else if ( seekingTransport ) {
+				return !( selected = dataTypeOrTransport );
+			}
+		} );
+		return selected;
+	}
+
+	return inspect( options.dataTypes[ 0 ] ) || !inspected[ "*" ] && inspect( "*" );
+}
+
+// A special extend for ajax options
+// that takes "flat" options (not to be deep extended)
+// Fixes #9887
+function ajaxExtend( target, src ) {
+	var key, deep,
+		flatOptions = jQuery.ajaxSettings.flatOptions || {};
+
+	for ( key in src ) {
+		if ( src[ key ] !== undefined ) {
+			( flatOptions[ key ] ? target : ( deep || ( deep = {} ) ) )[ key ] = src[ key ];
+		}
+	}
+	if ( deep ) {
+		jQuery.extend( true, target, deep );
+	}
+
+	return target;
+}
+
+/* Handles responses to an ajax request:
+ * - finds the right dataType (mediates between content-type and expected dataType)
+ * - returns the corresponding response
+ */
+function ajaxHandleResponses( s, jqXHR, responses ) {
+
+	var ct, type, finalDataType, firstDataType,
+		contents = s.contents,
+		dataTypes = s.dataTypes;
+
+	// Remove auto dataType and get content-type in the process
+	while ( dataTypes[ 0 ] === "*" ) {
+		dataTypes.shift();
+		if ( ct === undefined ) {
+			ct = s.mimeType || jqXHR.getResponseHeader( "Content-Type" );
+		}
+	}
+
+	// Check if we're dealing with a known content-type
+	if ( ct ) {
+		for ( type in contents ) {
+			if ( contents[ type ] && contents[ type ].test( ct ) ) {
+				dataTypes.unshift( type );
+				break;
+			}
+		}
+	}
+
+	// Check to see if we have a response for the expected dataType
+	if ( dataTypes[ 0 ] in responses ) {
+		finalDataType = dataTypes[ 0 ];
+	} else {
+
+		// Try convertible dataTypes
+		for ( type in responses ) {
+			if ( !dataTypes[ 0 ] || s.converters[ type + " " + dataTypes[ 0 ] ] ) {
+				finalDataType = type;
+				break;
+			}
+			if ( !firstDataType ) {
+				firstDataType = type;
+			}
+		}
+
+		// Or just use first one
+		finalDataType = finalDataType || firstDataType;
+	}
+
+	// If we found a dataType
+	// We add the dataType to the list if needed
+	// and return the corresponding response
+	if ( finalDataType ) {
+		if ( finalDataType !== dataTypes[ 0 ] ) {
+			dataTypes.unshift( finalDataType );
+		}
+		return responses[ finalDataType ];
+	}
+}
+
+/* Chain conversions given the request and the original response
+ * Also sets the responseXXX fields on the jqXHR instance
+ */
+function ajaxConvert( s, response, jqXHR, isSuccess ) {
+	var conv2, current, conv, tmp, prev,
+		converters = {},
+
+		// Work with a copy of dataTypes in case we need to modify it for conversion
+		dataTypes = s.dataTypes.slice();
+
+	// Create converters map with lowercased keys
+	if ( dataTypes[ 1 ] ) {
+		for ( conv in s.converters ) {
+			converters[ conv.toLowerCase() ] = s.converters[ conv ];
+		}
+	}
+
+	current = dataTypes.shift();
+
+	// Convert to each sequential dataType
+	while ( current ) {
+
+		if ( s.responseFields[ current ] ) {
+			jqXHR[ s.responseFields[ current ] ] = response;
+		}
+
+		// Apply the dataFilter if provided
+		if ( !prev && isSuccess && s.dataFilter ) {
+			response = s.dataFilter( response, s.dataType );
+		}
+
+		prev = current;
+		current = dataTypes.shift();
+
+		if ( current ) {
+
+		// There's only work to do if current dataType is non-auto
+			if ( current === "*" ) {
+
+				current = prev;
+
+			// Convert response if prev dataType is non-auto and differs from current
+			} else if ( prev !== "*" && prev !== current ) {
+
+				// Seek a direct converter
+				conv = converters[ prev + " " + current ] || converters[ "* " + current ];
+
+				// If none found, seek a pair
+				if ( !conv ) {
+					for ( conv2 in converters ) {
+
+						// If conv2 outputs current
+						tmp = conv2.split( " " );
+						if ( tmp[ 1 ] === current ) {
+
+							// If prev can be converted to accepted input
+							conv = converters[ prev + " " + tmp[ 0 ] ] ||
+								converters[ "* " + tmp[ 0 ] ];
+							if ( conv ) {
+
+								// Condense equivalence converters
+								if ( conv === true ) {
+									conv = converters[ conv2 ];
+
+								// Otherwise, insert the intermediate dataType
+								} else if ( converters[ conv2 ] !== true ) {
+									current = tmp[ 0 ];
+									dataTypes.unshift( tmp[ 1 ] );
+								}
+								break;
+							}
+						}
+					}
+				}
+
+				// Apply converter (if not an equivalence)
+				if ( conv !== true ) {
+
+					// Unless errors are allowed to bubble, catch and return them
+					if ( conv && s.throws ) {
+						response = conv( response );
+					} else {
+						try {
+							response = conv( response );
+						} catch ( e ) {
+							return {
+								state: "parsererror",
+								error: conv ? e : "No conversion from " + prev + " to " + current
+							};
+						}
+					}
+				}
+			}
+		}
+	}
+
+	return { state: "success", data: response };
+}
+
+jQuery.extend( {
+
+	// Counter for holding the number of active queries
+	active: 0,
+
+	// Last-Modified header cache for next request
+	lastModified: {},
+	etag: {},
+
+	ajaxSettings: {
+		url: location.href,
+		type: "GET",
+		isLocal: rlocalProtocol.test( location.protocol ),
+		global: true,
+		processData: true,
+		async: true,
+		contentType: "application/x-www-form-urlencoded; charset=UTF-8",
+		/*
+		timeout: 0,
+		data: null,
+		dataType: null,
+		username: null,
+		password: null,
+		cache: null,
+		throws: false,
+		traditional: false,
+		headers: {},
+		*/
+
+		accepts: {
+			"*": allTypes,
+			text: "text/plain",
+			html: "text/html",
+			xml: "application/xml, text/xml",
+			json: "application/json, text/javascript"
+		},
+
+		contents: {
+			xml: /\bxml\b/,
+			html: /\bhtml/,
+			json: /\bjson\b/
+		},
+
+		responseFields: {
+			xml: "responseXML",
+			text: "responseText",
+			json: "responseJSON"
+		},
+
+		// Data converters
+		// Keys separate source (or catchall "*") and destination types with a single space
+		converters: {
+
+			// Convert anything to text
+			"* text": String,
+
+			// Text to html (true = no transformation)
+			"text html": true,
+
+			// Evaluate text as a json expression
+			"text json": jQuery.parseJSON,
+
+			// Parse text as xml
+			"text xml": jQuery.parseXML
+		},
+
+		// For options that shouldn't be deep extended:
+		// you can add your own custom options here if
+		// and when you create one that shouldn't be
+		// deep extended (see ajaxExtend)
+		flatOptions: {
+			url: true,
+			context: true
+		}
+	},
+
+	// Creates a full fledged settings object into target
+	// with both ajaxSettings and settings fields.
+	// If target is omitted, writes into ajaxSettings.
+	ajaxSetup: function( target, settings ) {
+		return settings ?
+
+			// Building a settings object
+			ajaxExtend( ajaxExtend( target, jQuery.ajaxSettings ), settings ) :
+
+			// Extending ajaxSettings
+			ajaxExtend( jQuery.ajaxSettings, target );
+	},
+
+	ajaxPrefilter: addToPrefiltersOrTransports( prefilters ),
+	ajaxTransport: addToPrefiltersOrTransports( transports ),
+
+	// Main method
+	ajax: function( url, options ) {
+
+		// If url is an object, simulate pre-1.5 signature
+		if ( typeof url === "object" ) {
+			options = url;
+			url = undefined;
+		}
+
+		// Force options to be an object
+		options = options || {};
+
+		var transport,
+
+			// URL without anti-cache param
+			cacheURL,
+
+			// Response headers
+			responseHeadersString,
+			responseHeaders,
+
+			// timeout handle
+			timeoutTimer,
+
+			// Url cleanup var
+			urlAnchor,
+
+			// To know if global events are to be dispatched
+			fireGlobals,
+
+			// Loop variable
+			i,
+
+			// Create the final options object
+			s = jQuery.ajaxSetup( {}, options ),
+
+			// Callbacks context
+			callbackContext = s.context || s,
+
+			// Context for global events is callbackContext if it is a DOM node or jQuery collection
+			globalEventContext = s.context &&
+				( callbackContext.nodeType || callbackContext.jquery ) ?
+					jQuery( callbackContext ) :
+					jQuery.event,
+
+			// Deferreds
+			deferred = jQuery.Deferred(),
+			completeDeferred = jQuery.Callbacks( "once memory" ),
+
+			// Status-dependent callbacks
+			statusCode = s.statusCode || {},
+
+			// Headers (they are sent all at once)
+			requestHeaders = {},
+			requestHeadersNames = {},
+
+			// The jqXHR state
+			state = 0,
+
+			// Default abort message
+			strAbort = "canceled",
+
+			// Fake xhr
+			jqXHR = {
+				readyState: 0,
+
+				// Builds headers hashtable if needed
+				getResponseHeader: function( key ) {
+					var match;
+					if ( state === 2 ) {
+						if ( !responseHeaders ) {
+							responseHeaders = {};
+							while ( ( match = rheaders.exec( responseHeadersString ) ) ) {
+								responseHeaders[ match[ 1 ].toLowerCase() ] = match[ 2 ];
+							}
+						}
+						match = responseHeaders[ key.toLowerCase() ];
+					}
+					return match == null ? null : match;
+				},
+
+				// Raw string
+				getAllResponseHeaders: function() {
+					return state === 2 ? responseHeadersString : null;
+				},
+
+				// Caches the header
+				setRequestHeader: function( name, value ) {
+					var lname = name.toLowerCase();
+					if ( !state ) {
+						name = requestHeadersNames[ lname ] = requestHeadersNames[ lname ] || name;
+						requestHeaders[ name ] = value;
+					}
+					return this;
+				},
+
+				// Overrides response content-type header
+				overrideMimeType: function( type ) {
+					if ( !state ) {
+						s.mimeType = type;
+					}
+					return this;
+				},
+
+				// Status-dependent callbacks
+				statusCode: function( map ) {
+					var code;
+					if ( map ) {
+						if ( state < 2 ) {
+							for ( code in map ) {
+
+								// Lazy-add the new callback in a way that preserves old ones
+								statusCode[ code ] = [ statusCode[ code ], map[ code ] ];
+							}
+						} else {
+
+							// Execute the appropriate callbacks
+							jqXHR.always( map[ jqXHR.status ] );
+						}
+					}
+					return this;
+				},
+
+				// Cancel the request
+				abort: function( statusText ) {
+					var finalText = statusText || strAbort;
+					if ( transport ) {
+						transport.abort( finalText );
+					}
+					done( 0, finalText );
+					return this;
+				}
+			};
+
+		// Attach deferreds
+		deferred.promise( jqXHR ).complete = completeDeferred.add;
+		jqXHR.success = jqXHR.done;
+		jqXHR.error = jqXHR.fail;
+
+		// Remove hash character (#7531: and string promotion)
+		// Add protocol if not provided (prefilters might expect it)
+		// Handle falsy url in the settings object (#10093: consistency with old signature)
+		// We also use the url parameter if available
+		s.url = ( ( url || s.url || location.href ) + "" ).replace( rhash, "" )
+			.replace( rprotocol, location.protocol + "//" );
+
+		// Alias method option to type as per ticket #12004
+		s.type = options.method || options.type || s.method || s.type;
+
+		// Extract dataTypes list
+		s.dataTypes = jQuery.trim( s.dataType || "*" ).toLowerCase().match( rnotwhite ) || [ "" ];
+
+		// A cross-domain request is in order when the origin doesn't match the current origin.
+		if ( s.crossDomain == null ) {
+			urlAnchor = document.createElement( "a" );
+
+			// Support: IE8-11+
+			// IE throws exception if url is malformed, e.g. http://example.com:80x/
+			try {
+				urlAnchor.href = s.url;
+
+				// Support: IE8-11+
+				// Anchor's host property isn't correctly set when s.url is relative
+				urlAnchor.href = urlAnchor.href;
+				s.crossDomain = originAnchor.protocol + "//" + originAnchor.host !==
+					urlAnchor.protocol + "//" + urlAnchor.host;
+			} catch ( e ) {
+
+				// If there is an error parsing the URL, assume it is crossDomain,
+				// it can be rejected by the transport if it is invalid
+				s.crossDomain = true;
+			}
+		}
+
+		// Convert data if not already a string
+		if ( s.data && s.processData && typeof s.data !== "string" ) {
+			s.data = jQuery.param( s.data, s.traditional );
+		}
+
+		// Apply prefilters
+		inspectPrefiltersOrTransports( prefilters, s, options, jqXHR );
+
+		// If request was aborted inside a prefilter, stop there
+		if ( state === 2 ) {
+			return jqXHR;
+		}
+
+		// We can fire global events as of now if asked to
+		// Don't fire events if jQuery.event is undefined in an AMD-usage scenario (#15118)
+		fireGlobals = jQuery.event && s.global;
+
+		// Watch for a new set of requests
+		if ( fireGlobals && jQuery.active++ === 0 ) {
+			jQuery.event.trigger( "ajaxStart" );
+		}
+
+		// Uppercase the type
+		s.type = s.type.toUpperCase();
+
+		// Determine if request has content
+		s.hasContent = !rnoContent.test( s.type );
+
+		// Save the URL in case we're toying with the If-Modified-Since
+		// and/or If-None-Match header later on
+		cacheURL = s.url;
+
+		// More options handling for requests with no content
+		if ( !s.hasContent ) {
+
+			// If data is available, append data to url
+			if ( s.data ) {
+				cacheURL = ( s.url += ( rquery.test( cacheURL ) ? "&" : "?" ) + s.data );
+
+				// #9682: remove data so that it's not used in an eventual retry
+				delete s.data;
+			}
+
+			// Add anti-cache in url if needed
+			if ( s.cache === false ) {
+				s.url = rts.test( cacheURL ) ?
+
+					// If there is already a '_' parameter, set its value
+					cacheURL.replace( rts, "$1_=" + nonce++ ) :
+
+					// Otherwise add one to the end
+					cacheURL + ( rquery.test( cacheURL ) ? "&" : "?" ) + "_=" + nonce++;
+			}
+		}
+
+		// Set the If-Modified-Since and/or If-None-Match header, if in ifModified mode.
+		if ( s.ifModified ) {
+			if ( jQuery.lastModified[ cacheURL ] ) {
+				jqXHR.setRequestHeader( "If-Modified-Since", jQuery.lastModified[ cacheURL ] );
+			}
+			if ( jQuery.etag[ cacheURL ] ) {
+				jqXHR.setRequestHeader( "If-None-Match", jQuery.etag[ cacheURL ] );
+			}
+		}
+
+		// Set the correct header, if data is being sent
+		if ( s.data && s.hasContent && s.contentType !== false || options.contentType ) {
+			jqXHR.setRequestHeader( "Content-Type", s.contentType );
+		}
+
+		// Set the Accepts header for the server, depending on the dataType
+		jqXHR.setRequestHeader(
+			"Accept",
+			s.dataTypes[ 0 ] && s.accepts[ s.dataTypes[ 0 ] ] ?
+				s.accepts[ s.dataTypes[ 0 ] ] +
+					( s.dataTypes[ 0 ] !== "*" ? ", " + allTypes + "; q=0.01" : "" ) :
+				s.accepts[ "*" ]
+		);
+
+		// Check for headers option
+		for ( i in s.headers ) {
+			jqXHR.setRequestHeader( i, s.headers[ i ] );
+		}
+
+		// Allow custom headers/mimetypes and early abort
+		if ( s.beforeSend &&
+			( s.beforeSend.call( callbackContext, jqXHR, s ) === false || state === 2 ) ) {
+
+			// Abort if not done already and return
+			return jqXHR.abort();
+		}
+
+		// Aborting is no longer a cancellation
+		strAbort = "abort";
+
+		// Install callbacks on deferreds
+		for ( i in { success: 1, error: 1, complete: 1 } ) {
+			jqXHR[ i ]( s[ i ] );
+		}
+
+		// Get transport
+		transport = inspectPrefiltersOrTransports( transports, s, options, jqXHR );
+
+		// If no transport, we auto-abort
+		if ( !transport ) {
+			done( -1, "No Transport" );
+		} else {
+			jqXHR.readyState = 1;
+
+			// Send global event
+			if ( fireGlobals ) {
+				globalEventContext.trigger( "ajaxSend", [ jqXHR, s ] );
+			}
+
+			// If request was aborted inside ajaxSend, stop there
+			if ( state === 2 ) {
+				return jqXHR;
+			}
+
+			// Timeout
+			if ( s.async && s.timeout > 0 ) {
+				timeoutTimer = window.setTimeout( function() {
+					jqXHR.abort( "timeout" );
+				}, s.timeout );
+			}
+
+			try {
+				state = 1;
+				transport.send( requestHeaders, done );
+			} catch ( e ) {
+
+				// Propagate exception as error if not done
+				if ( state < 2 ) {
+					done( -1, e );
+
+				// Simply rethrow otherwise
+				} else {
+					throw e;
+				}
+			}
+		}
+
+		// Callback for when everything is done
+		function done( status, nativeStatusText, responses, headers ) {
+			var isSuccess, success, error, response, modified,
+				statusText = nativeStatusText;
+
+			// Called once
+			if ( state === 2 ) {
+				return;
+			}
+
+			// State is "done" now
+			state = 2;
+
+			// Clear timeout if it exists
+			if ( timeoutTimer ) {
+				window.clearTimeout( timeoutTimer );
+			}
+
+			// Dereference transport for early garbage collection
+			// (no matter how long the jqXHR object will be used)
+			transport = undefined;
+
+			// Cache response headers
+			responseHeadersString = headers || "";
+
+			// Set readyState
+			jqXHR.readyState = status > 0 ? 4 : 0;
+
+			// Determine if successful
+			isSuccess = status >= 200 && status < 300 || status === 304;
+
+			// Get response data
+			if ( responses ) {
+				response = ajaxHandleResponses( s, jqXHR, responses );
+			}
+
+			// Convert no matter what (that way responseXXX fields are always set)
+			response = ajaxConvert( s, response, jqXHR, isSuccess );
+
+			// If successful, handle type chaining
+			if ( isSuccess ) {
+
+				// Set the If-Modified-Since and/or If-None-Match header, if in ifModified mode.
+				if ( s.ifModified ) {
+					modified = jqXHR.getResponseHeader( "Last-Modified" );
+					if ( modified ) {
+						jQuery.lastModified[ cacheURL ] = modified;
+					}
+					modified = jqXHR.getResponseHeader( "etag" );
+					if ( modified ) {
+						jQuery.etag[ cacheURL ] = modified;
+					}
+				}
+
+				// if no content
+				if ( status === 204 || s.type === "HEAD" ) {
+					statusText = "nocontent";
+
+				// if not modified
+				} else if ( status === 304 ) {
+					statusText = "notmodified";
+
+				// If we have data, let's convert it
+				} else {
+					statusText = response.state;
+					success = response.data;
+					error = response.error;
+					isSuccess = !error;
+				}
+			} else {
+
+				// Extract error from statusText and normalize for non-aborts
+				error = statusText;
+				if ( status || !statusText ) {
+					statusText = "error";
+					if ( status < 0 ) {
+						status = 0;
+					}
+				}
+			}
+
+			// Set data for the fake xhr object
+			jqXHR.status = status;
+			jqXHR.statusText = ( nativeStatusText || statusText ) + "";
+
+			// Success/Error
+			if ( isSuccess ) {
+				deferred.resolveWith( callbackContext, [ success, statusText, jqXHR ] );
+			} else {
+				deferred.rejectWith( callbackContext, [ jqXHR, statusText, error ] );
+			}
+
+			// Status-dependent callbacks
+			jqXHR.statusCode( statusCode );
+			statusCode = undefined;
+
+			if ( fireGlobals ) {
+				globalEventContext.trigger( isSuccess ? "ajaxSuccess" : "ajaxError",
+					[ jqXHR, s, isSuccess ? success : error ] );
+			}
+
+			// Complete
+			completeDeferred.fireWith( callbackContext, [ jqXHR, statusText ] );
+
+			if ( fireGlobals ) {
+				globalEventContext.trigger( "ajaxComplete", [ jqXHR, s ] );
+
+				// Handle the global AJAX counter
+				if ( !( --jQuery.active ) ) {
+					jQuery.event.trigger( "ajaxStop" );
+				}
+			}
+		}
+
+		return jqXHR;
+	},
+
+	getJSON: function( url, data, callback ) {
+		return jQuery.get( url, data, callback, "json" );
+	},
+
+	getScript: function( url, callback ) {
+		return jQuery.get( url, undefined, callback, "script" );
+	}
+} );
+
+jQuery.each( [ "get", "post" ], function( i, method ) {
+	jQuery[ method ] = function( url, data, callback, type ) {
+
+		// Shift arguments if data argument was omitted
+		if ( jQuery.isFunction( data ) ) {
+			type = type || callback;
+			callback = data;
+			data = undefined;
+		}
+
+		// The url can be an options object (which then must have .url)
+		return jQuery.ajax( jQuery.extend( {
+			url: url,
+			type: method,
+			dataType: type,
+			data: data,
+			success: callback
+		}, jQuery.isPlainObject( url ) && url ) );
+	};
+} );
+
+
+jQuery._evalUrl = function( url ) {
+	return jQuery.ajax( {
+		url: url,
+
+		// Make this explicit, since user can override this through ajaxSetup (#11264)
+		type: "GET",
+		dataType: "script",
+		async: false,
+		global: false,
+		"throws": true
+	} );
+};
+
+
+jQuery.fn.extend( {
+	wrapAll: function( html ) {
+		var wrap;
+
+		if ( jQuery.isFunction( html ) ) {
+			return this.each( function( i ) {
+				jQuery( this ).wrapAll( html.call( this, i ) );
+			} );
+		}
+
+		if ( this[ 0 ] ) {
+
+			// The elements to wrap the target around
+			wrap = jQuery( html, this[ 0 ].ownerDocument ).eq( 0 ).clone( true );
+
+			if ( this[ 0 ].parentNode ) {
+				wrap.insertBefore( this[ 0 ] );
+			}
+
+			wrap.map( function() {
+				var elem = this;
+
+				while ( elem.firstElementChild ) {
+					elem = elem.firstElementChild;
+				}
+
+				return elem;
+			} ).append( this );
+		}
+
+		return this;
+	},
+
+	wrapInner: function( html ) {
+		if ( jQuery.isFunction( html ) ) {
+			return this.each( function( i ) {
+				jQuery( this ).wrapInner( html.call( this, i ) );
+			} );
+		}
+
+		return this.each( function() {
+			var self = jQuery( this ),
+				contents = self.contents();
+
+			if ( contents.length ) {
+				contents.wrapAll( html );
+
+			} else {
+				self.append( html );
+			}
+		} );
+	},
+
+	wrap: function( html ) {
+		var isFunction = jQuery.isFunction( html );
+
+		return this.each( function( i ) {
+			jQuery( this ).wrapAll( isFunction ? html.call( this, i ) : html );
+		} );
+	},
+
+	unwrap: function() {
+		return this.parent().each( function() {
+			if ( !jQuery.nodeName( this, "body" ) ) {
+				jQuery( this ).replaceWith( this.childNodes );
+			}
+		} ).end();
+	}
+} );
+
+
+jQuery.expr.filters.hidden = function( elem ) {
+	return !jQuery.expr.filters.visible( elem );
+};
+jQuery.expr.filters.visible = function( elem ) {
+
+	// Support: Opera <= 12.12
+	// Opera reports offsetWidths and offsetHeights less than zero on some elements
+	// Use OR instead of AND as the element is not visible if either is true
+	// See tickets #10406 and #13132
+	return elem.offsetWidth > 0 || elem.offsetHeight > 0 || elem.getClientRects().length > 0;
+};
+
+
+
+
+var r20 = /%20/g,
+	rbracket = /\[\]$/,
+	rCRLF = /\r?\n/g,
+	rsubmitterTypes = /^(?:submit|button|image|reset|file)$/i,
+	rsubmittable = /^(?:input|select|textarea|keygen)/i;
+
+function buildParams( prefix, obj, traditional, add ) {
+	var name;
+
+	if ( jQuery.isArray( obj ) ) {
+
+		// Serialize array item.
+		jQuery.each( obj, function( i, v ) {
+			if ( traditional || rbracket.test( prefix ) ) {
+
+				// Treat each array item as a scalar.
+				add( prefix, v );
+
+			} else {
+
+				// Item is non-scalar (array or object), encode its numeric index.
+				buildParams(
+					prefix + "[" + ( typeof v === "object" && v != null ? i : "" ) + "]",
+					v,
+					traditional,
+					add
+				);
+			}
+		} );
+
+	} else if ( !traditional && jQuery.type( obj ) === "object" ) {
+
+		// Serialize object item.
+		for ( name in obj ) {
+			buildParams( prefix + "[" + name + "]", obj[ name ], traditional, add );
+		}
+
+	} else {
+
+		// Serialize scalar item.
+		add( prefix, obj );
+	}
+}
+
+// Serialize an array of form elements or a set of
+// key/values into a query string
+jQuery.param = function( a, traditional ) {
+	var prefix,
+		s = [],
+		add = function( key, value ) {
+
+			// If value is a function, invoke it and return its value
+			value = jQuery.isFunction( value ) ? value() : ( value == null ? "" : value );
+			s[ s.length ] = encodeURIComponent( key ) + "=" + encodeURIComponent( value );
+		};
+
+	// Set traditional to true for jQuery <= 1.3.2 behavior.
+	if ( traditional === undefined ) {
+		traditional = jQuery.ajaxSettings && jQuery.ajaxSettings.traditional;
+	}
+
+	// If an array was passed in, assume that it is an array of form elements.
+	if ( jQuery.isArray( a ) || ( a.jquery && !jQuery.isPlainObject( a ) ) ) {
+
+		// Serialize the form elements
+		jQuery.each( a, function() {
+			add( this.name, this.value );
+		} );
+
+	} else {
+
+		// If traditional, encode the "old" way (the way 1.3.2 or older
+		// did it), otherwise encode params recursively.
+		for ( prefix in a ) {
+			buildParams( prefix, a[ prefix ], traditional, add );
+		}
+	}
+
+	// Return the resulting serialization
+	return s.join( "&" ).replace( r20, "+" );
+};
+
+jQuery.fn.extend( {
+	serialize: function() {
+		return jQuery.param( this.serializeArray() );
+	},
+	serializeArray: function() {
+		return this.map( function() {
+
+			// Can add propHook for "elements" to filter or add form elements
+			var elements = jQuery.prop( this, "elements" );
+			return elements ? jQuery.makeArray( elements ) : this;
+		} )
+		.filter( function() {
+			var type = this.type;
+
+			// Use .is( ":disabled" ) so that fieldset[disabled] works
+			return this.name && !jQuery( this ).is( ":disabled" ) &&
+				rsubmittable.test( this.nodeName ) && !rsubmitterTypes.test( type ) &&
+				( this.checked || !rcheckableType.test( type ) );
+		} )
+		.map( function( i, elem ) {
+			var val = jQuery( this ).val();
+
+			return val == null ?
+				null :
+				jQuery.isArray( val ) ?
+					jQuery.map( val, function( val ) {
+						return { name: elem.name, value: val.replace( rCRLF, "\r\n" ) };
+					} ) :
+					{ name: elem.name, value: val.replace( rCRLF, "\r\n" ) };
+		} ).get();
+	}
+} );
+
+
+jQuery.ajaxSettings.xhr = function() {
+	try {
+		return new window.XMLHttpRequest();
+	} catch ( e ) {}
+};
+
+var xhrSuccessStatus = {
+
+		// File protocol always yields status code 0, assume 200
+		0: 200,
+
+		// Support: IE9
+		// #1450: sometimes IE returns 1223 when it should be 204
+		1223: 204
+	},
+	xhrSupported = jQuery.ajaxSettings.xhr();
+
+support.cors = !!xhrSupported && ( "withCredentials" in xhrSupported );
+support.ajax = xhrSupported = !!xhrSupported;
+
+jQuery.ajaxTransport( function( options ) {
+	var callback, errorCallback;
+
+	// Cross domain only allowed if supported through XMLHttpRequest
+	if ( support.cors || xhrSupported && !options.crossDomain ) {
+		return {
+			send: function( headers, complete ) {
+				var i,
+					xhr = options.xhr();
+
+				xhr.open(
+					options.type,
+					options.url,
+					options.async,
+					options.username,
+					options.password
+				);
+
+				// Apply custom fields if provided
+				if ( options.xhrFields ) {
+					for ( i in options.xhrFields ) {
+						xhr[ i ] = options.xhrFields[ i ];
+					}
+				}
+
+				// Override mime type if needed
+				if ( options.mimeType && xhr.overrideMimeType ) {
+					xhr.overrideMimeType( options.mimeType );
+				}
+
+				// X-Requested-With header
+				// For cross-domain requests, seeing as conditions for a preflight are
+				// akin to a jigsaw puzzle, we simply never set it to be sure.
+				// (it can always be set on a per-request basis or even using ajaxSetup)
+				// For same-domain requests, won't change header if already provided.
+				if ( !options.crossDomain && !headers[ "X-Requested-With" ] ) {
+					headers[ "X-Requested-With" ] = "XMLHttpRequest";
+				}
+
+				// Set headers
+				for ( i in headers ) {
+					xhr.setRequestHeader( i, headers[ i ] );
+				}
+
+				// Callback
+				callback = function( type ) {
+					return function() {
+						if ( callback ) {
+							callback = errorCallback = xhr.onload =
+								xhr.onerror = xhr.onabort = xhr.onreadystatechange = null;
+
+							if ( type === "abort" ) {
+								xhr.abort();
+							} else if ( type === "error" ) {
+
+								// Support: IE9
+								// On a manual native abort, IE9 throws
+								// errors on any property access that is not readyState
+								if ( typeof xhr.status !== "number" ) {
+									complete( 0, "error" );
+								} else {
+									complete(
+
+										// File: protocol always yields status 0; see #8605, #14207
+										xhr.status,
+										xhr.statusText
+									);
+								}
+							} else {
+								complete(
+									xhrSuccessStatus[ xhr.status ] || xhr.status,
+									xhr.statusText,
+
+									// Support: IE9 only
+									// IE9 has no XHR2 but throws on binary (trac-11426)
+									// For XHR2 non-text, let the caller handle it (gh-2498)
+									( xhr.responseType || "text" ) !== "text"  ||
+									typeof xhr.responseText !== "string" ?
+										{ binary: xhr.response } :
+										{ text: xhr.responseText },
+									xhr.getAllResponseHeaders()
+								);
+							}
+						}
+					};
+				};
+
+				// Listen to events
+				xhr.onload = callback();
+				errorCallback = xhr.onerror = callback( "error" );
+
+				// Support: IE9
+				// Use onreadystatechange to replace onabort
+				// to handle uncaught aborts
+				if ( xhr.onabort !== undefined ) {
+					xhr.onabort = errorCallback;
+				} else {
+					xhr.onreadystatechange = function() {
+
+						// Check readyState before timeout as it changes
+						if ( xhr.readyState === 4 ) {
+
+							// Allow onerror to be called first,
+							// but that will not handle a native abort
+							// Also, save errorCallback to a variable
+							// as xhr.onerror cannot be accessed
+							window.setTimeout( function() {
+								if ( callback ) {
+									errorCallback();
+								}
+							} );
+						}
+					};
+				}
+
+				// Create the abort callback
+				callback = callback( "abort" );
+
+				try {
+
+					// Do send the request (this may raise an exception)
+					xhr.send( options.hasContent && options.data || null );
+				} catch ( e ) {
+
+					// #14683: Only rethrow if this hasn't been notified as an error yet
+					if ( callback ) {
+						throw e;
+					}
+				}
+			},
+
+			abort: function() {
+				if ( callback ) {
+					callback();
+				}
+			}
+		};
+	}
+} );
+
+
+
+
+// Install script dataType
+jQuery.ajaxSetup( {
+	accepts: {
+		script: "text/javascript, application/javascript, " +
+			"application/ecmascript, application/x-ecmascript"
+	},
+	contents: {
+		script: /\b(?:java|ecma)script\b/
+	},
+	converters: {
+		"text script": function( text ) {
+			jQuery.globalEval( text );
+			return text;
+		}
+	}
+} );
+
+// Handle cache's special case and crossDomain
+jQuery.ajaxPrefilter( "script", function( s ) {
+	if ( s.cache === undefined ) {
+		s.cache = false;
+	}
+	if ( s.crossDomain ) {
+		s.type = "GET";
+	}
+} );
+
+// Bind script tag hack transport
+jQuery.ajaxTransport( "script", function( s ) {
+
+	// This transport only deals with cross domain requests
+	if ( s.crossDomain ) {
+		var script, callback;
+		return {
+			send: function( _, complete ) {
+				script = jQuery( "<script>" ).prop( {
+					charset: s.scriptCharset,
+					src: s.url
+				} ).on(
+					"load error",
+					callback = function( evt ) {
+						script.remove();
+						callback = null;
+						if ( evt ) {
+							complete( evt.type === "error" ? 404 : 200, evt.type );
+						}
+					}
+				);
+
+				// Use native DOM manipulation to avoid our domManip AJAX trickery
+				document.head.appendChild( script[ 0 ] );
+			},
+			abort: function() {
+				if ( callback ) {
+					callback();
+				}
+			}
+		};
+	}
+} );
+
+
+
+
+var oldCallbacks = [],
+	rjsonp = /(=)\?(?=&|$)|\?\?/;
+
+// Default jsonp settings
+jQuery.ajaxSetup( {
+	jsonp: "callback",
+	jsonpCallback: function() {
+		var callback = oldCallbacks.pop() || ( jQuery.expando + "_" + ( nonce++ ) );
+		this[ callback ] = true;
+		return callback;
+	}
+} );
+
+// Detect, normalize options and install callbacks for jsonp requests
+jQuery.ajaxPrefilter( "json jsonp", function( s, originalSettings, jqXHR ) {
+
+	var callbackName, overwritten, responseContainer,
+		jsonProp = s.jsonp !== false && ( rjsonp.test( s.url ) ?
+			"url" :
+			typeof s.data === "string" &&
+				( s.contentType || "" )
+					.indexOf( "application/x-www-form-urlencoded" ) === 0 &&
+				rjsonp.test( s.data ) && "data"
+		);
+
+	// Handle iff the expected data type is "jsonp" or we have a parameter to set
+	if ( jsonProp || s.dataTypes[ 0 ] === "jsonp" ) {
+
+		// Get callback name, remembering preexisting value associated with it
+		callbackName = s.jsonpCallback = jQuery.isFunction( s.jsonpCallback ) ?
+			s.jsonpCallback() :
+			s.jsonpCallback;
+
+		// Insert callback into url or form data
+		if ( jsonProp ) {
+			s[ jsonProp ] = s[ jsonProp ].replace( rjsonp, "$1" + callbackName );
+		} else if ( s.jsonp !== false ) {
+			s.url += ( rquery.test( s.url ) ? "&" : "?" ) + s.jsonp + "=" + callbackName;
+		}
+
+		// Use data converter to retrieve json after script execution
+		s.converters[ "script json" ] = function() {
+			if ( !responseContainer ) {
+				jQuery.error( callbackName + " was not called" );
+			}
+			return responseContainer[ 0 ];
+		};
+
+		// Force json dataType
+		s.dataTypes[ 0 ] = "json";
+
+		// Install callback
+		overwritten = window[ callbackName ];
+		window[ callbackName ] = function() {
+			responseContainer = arguments;
+		};
+
+		// Clean-up function (fires after converters)
+		jqXHR.always( function() {
+
+			// If previous value didn't exist - remove it
+			if ( overwritten === undefined ) {
+				jQuery( window ).removeProp( callbackName );
+
+			// Otherwise restore preexisting value
+			} else {
+				window[ callbackName ] = overwritten;
+			}
+
+			// Save back as free
+			if ( s[ callbackName ] ) {
+
+				// Make sure that re-using the options doesn't screw things around
+				s.jsonpCallback = originalSettings.jsonpCallback;
+
+				// Save the callback name for future use
+				oldCallbacks.push( callbackName );
+			}
+
+			// Call if it was a function and we have a response
+			if ( responseContainer && jQuery.isFunction( overwritten ) ) {
+				overwritten( responseContainer[ 0 ] );
+			}
+
+			responseContainer = overwritten = undefined;
+		} );
+
+		// Delegate to script
+		return "script";
+	}
+} );
+
+
+
+
+// Support: Safari 8+
+// In Safari 8 documents created via document.implementation.createHTMLDocument
+// collapse sibling forms: the second one becomes a child of the first one.
+// Because of that, this security measure has to be disabled in Safari 8.
+// https://bugs.webkit.org/show_bug.cgi?id=137337
+support.createHTMLDocument = ( function() {
+	var body = document.implementation.createHTMLDocument( "" ).body;
+	body.innerHTML = "<form></form><form></form>";
+	return body.childNodes.length === 2;
+} )();
+
+
+// Argument "data" should be string of html
+// context (optional): If specified, the fragment will be created in this context,
+// defaults to document
+// keepScripts (optional): If true, will include scripts passed in the html string
+jQuery.parseHTML = function( data, context, keepScripts ) {
+	if ( !data || typeof data !== "string" ) {
+		return null;
+	}
+	if ( typeof context === "boolean" ) {
+		keepScripts = context;
+		context = false;
+	}
+
+	// Stop scripts or inline event handlers from being executed immediately
+	// by using document.implementation
+	context = context || ( support.createHTMLDocument ?
+		document.implementation.createHTMLDocument( "" ) :
+		document );
+
+	var parsed = rsingleTag.exec( data ),
+		scripts = !keepScripts && [];
+
+	// Single tag
+	if ( parsed ) {
+		return [ context.createElement( parsed[ 1 ] ) ];
+	}
+
+	parsed = buildFragment( [ data ], context, scripts );
+
+	if ( scripts && scripts.length ) {
+		jQuery( scripts ).remove();
+	}
+
+	return jQuery.merge( [], parsed.childNodes );
+};
+
+
+// Keep a copy of the old load method
+var _load = jQuery.fn.load;
+
+/**
+ * Load a url into a page
+ */
+jQuery.fn.load = function( url, params, callback ) {
+	if ( typeof url !== "string" && _load ) {
+		return _load.apply( this, arguments );
+	}
+
+	var selector, type, response,
+		self = this,
+		off = url.indexOf( " " );
+
+	if ( off > -1 ) {
+		selector = jQuery.trim( url.slice( off ) );
+		url = url.slice( 0, off );
+	}
+
+	// If it's a function
+	if ( jQuery.isFunction( params ) ) {
+
+		// We assume that it's the callback
+		callback = params;
+		params = undefined;
+
+	// Otherwise, build a param string
+	} else if ( params && typeof params === "object" ) {
+		type = "POST";
+	}
+
+	// If we have elements to modify, make the request
+	if ( self.length > 0 ) {
+		jQuery.ajax( {
+			url: url,
+
+			// If "type" variable is undefined, then "GET" method will be used.
+			// Make value of this field explicit since
+			// user can override it through ajaxSetup method
+			type: type || "GET",
+			dataType: "html",
+			data: params
+		} ).done( function( responseText ) {
+
+			// Save response for use in complete callback
+			response = arguments;
+
+			self.html( selector ?
+
+				// If a selector was specified, locate the right elements in a dummy div
+				// Exclude scripts to avoid IE 'Permission Denied' errors
+				jQuery( "<div>" ).append( jQuery.parseHTML( responseText ) ).find( selector ) :
+
+				// Otherwise use the full result
+				responseText );
+
+		// If the request succeeds, this function gets "data", "status", "jqXHR"
+		// but they are ignored because response was set above.
+		// If it fails, this function gets "jqXHR", "status", "error"
+		} ).always( callback && function( jqXHR, status ) {
+			self.each( function() {
+				callback.apply( self, response || [ jqXHR.responseText, status, jqXHR ] );
+			} );
+		} );
+	}
+
+	return this;
+};
+
+
+
+
+// Attach a bunch of functions for handling common AJAX events
+jQuery.each( [
+	"ajaxStart",
+	"ajaxStop",
+	"ajaxComplete",
+	"ajaxError",
+	"ajaxSuccess",
+	"ajaxSend"
+], function( i, type ) {
+	jQuery.fn[ type ] = function( fn ) {
+		return this.on( type, fn );
+	};
+} );
+
+
+
+
+jQuery.expr.filters.animated = function( elem ) {
+	return jQuery.grep( jQuery.timers, function( fn ) {
+		return elem === fn.elem;
+	} ).length;
+};
+
+
+
+
+/**
+ * Gets a window from an element
+ */
+function getWindow( elem ) {
+	return jQuery.isWindow( elem ) ? elem : elem.nodeType === 9 && elem.defaultView;
+}
+
+jQuery.offset = {
+	setOffset: function( elem, options, i ) {
+		var curPosition, curLeft, curCSSTop, curTop, curOffset, curCSSLeft, calculatePosition,
+			position = jQuery.css( elem, "position" ),
+			curElem = jQuery( elem ),
+			props = {};
+
+		// Set position first, in-case top/left are set even on static elem
+		if ( position === "static" ) {
+			elem.style.position = "relative";
+		}
+
+		curOffset = curElem.offset();
+		curCSSTop = jQuery.css( elem, "top" );
+		curCSSLeft = jQuery.css( elem, "left" );
+		calculatePosition = ( position === "absolute" || position === "fixed" ) &&
+			( curCSSTop + curCSSLeft ).indexOf( "auto" ) > -1;
+
+		// Need to be able to calculate position if either
+		// top or left is auto and position is either absolute or fixed
+		if ( calculatePosition ) {
+			curPosition = curElem.position();
+			curTop = curPosition.top;
+			curLeft = curPosition.left;
+
+		} else {
+			curTop = parseFloat( curCSSTop ) || 0;
+			curLeft = parseFloat( curCSSLeft ) || 0;
+		}
+
+		if ( jQuery.isFunction( options ) ) {
+
+			// Use jQuery.extend here to allow modification of coordinates argument (gh-1848)
+			options = options.call( elem, i, jQuery.extend( {}, curOffset ) );
+		}
+
+		if ( options.top != null ) {
+			props.top = ( options.top - curOffset.top ) + curTop;
+		}
+		if ( options.left != null ) {
+			props.left = ( options.left - curOffset.left ) + curLeft;
+		}
+
+		if ( "using" in options ) {
+			options.using.call( elem, props );
+
+		} else {
+			curElem.css( props );
+		}
+	}
+};
+
+jQuery.fn.extend( {
+	offset: function( options ) {
+		if ( arguments.length ) {
+			return options === undefined ?
+				this :
+				this.each( function( i ) {
+					jQuery.offset.setOffset( this, options, i );
+				} );
+		}
+
+		var docElem, win,
+			elem = this[ 0 ],
+			box = { top: 0, left: 0 },
+			doc = elem && elem.ownerDocument;
+
+		if ( !doc ) {
+			return;
+		}
+
+		docElem = doc.documentElement;
+
+		// Make sure it's not a disconnected DOM node
+		if ( !jQuery.contains( docElem, elem ) ) {
+			return box;
+		}
+
+		box = elem.getBoundingClientRect();
+		win = getWindow( doc );
+		return {
+			top: box.top + win.pageYOffset - docElem.clientTop,
+			left: box.left + win.pageXOffset - docElem.clientLeft
+		};
+	},
+
+	position: function() {
+		if ( !this[ 0 ] ) {
+			return;
+		}
+
+		var offsetParent, offset,
+			elem = this[ 0 ],
+			parentOffset = { top: 0, left: 0 };
+
+		// Fixed elements are offset from window (parentOffset = {top:0, left: 0},
+		// because it is its only offset parent
+		if ( jQuery.css( elem, "position" ) === "fixed" ) {
+
+			// Assume getBoundingClientRect is there when computed position is fixed
+			offset = elem.getBoundingClientRect();
+
+		} else {
+
+			// Get *real* offsetParent
+			offsetParent = this.offsetParent();
+
+			// Get correct offsets
+			offset = this.offset();
+			if ( !jQuery.nodeName( offsetParent[ 0 ], "html" ) ) {
+				parentOffset = offsetParent.offset();
+			}
+
+			// Add offsetParent borders
+			// Subtract offsetParent scroll positions
+			parentOffset.top += jQuery.css( offsetParent[ 0 ], "borderTopWidth", true ) -
+				offsetParent.scrollTop();
+			parentOffset.left += jQuery.css( offsetParent[ 0 ], "borderLeftWidth", true ) -
+				offsetParent.scrollLeft();
+		}
+
+		// Subtract parent offsets and element margins
+		return {
+			top: offset.top - parentOffset.top - jQuery.css( elem, "marginTop", true ),
+			left: offset.left - parentOffset.left - jQuery.css( elem, "marginLeft", true )
+		};
+	},
+
+	// This method will return documentElement in the following cases:
+	// 1) For the element inside the iframe without offsetParent, this method will return
+	//    documentElement of the parent window
+	// 2) For the hidden or detached element
+	// 3) For body or html element, i.e. in case of the html node - it will return itself
+	//
+	// but those exceptions were never presented as a real life use-cases
+	// and might be considered as more preferable results.
+	//
+	// This logic, however, is not guaranteed and can change at any point in the future
+	offsetParent: function() {
+		return this.map( function() {
+			var offsetParent = this.offsetParent;
+
+			while ( offsetParent && jQuery.css( offsetParent, "position" ) === "static" ) {
+				offsetParent = offsetParent.offsetParent;
+			}
+
+			return offsetParent || documentElement;
+		} );
+	}
+} );
+
+// Create scrollLeft and scrollTop methods
+jQuery.each( { scrollLeft: "pageXOffset", scrollTop: "pageYOffset" }, function( method, prop ) {
+	var top = "pageYOffset" === prop;
+
+	jQuery.fn[ method ] = function( val ) {
+		return access( this, function( elem, method, val ) {
+			var win = getWindow( elem );
+
+			if ( val === undefined ) {
+				return win ? win[ prop ] : elem[ method ];
+			}
+
+			if ( win ) {
+				win.scrollTo(
+					!top ? val : win.pageXOffset,
+					top ? val : win.pageYOffset
+				);
+
+			} else {
+				elem[ method ] = val;
+			}
+		}, method, val, arguments.length );
+	};
+} );
+
+// Support: Safari<7-8+, Chrome<37-44+
+// Add the top/left cssHooks using jQuery.fn.position
+// Webkit bug: https://bugs.webkit.org/show_bug.cgi?id=29084
+// Blink bug: https://code.google.com/p/chromium/issues/detail?id=229280
+// getComputedStyle returns percent when specified for top/left/bottom/right;
+// rather than make the css module depend on the offset module, just check for it here
+jQuery.each( [ "top", "left" ], function( i, prop ) {
+	jQuery.cssHooks[ prop ] = addGetHookIf( support.pixelPosition,
+		function( elem, computed ) {
+			if ( computed ) {
+				computed = curCSS( elem, prop );
+
+				// If curCSS returns percentage, fallback to offset
+				return rnumnonpx.test( computed ) ?
+					jQuery( elem ).position()[ prop ] + "px" :
+					computed;
+			}
+		}
+	);
+} );
+
+
+// Create innerHeight, innerWidth, height, width, outerHeight and outerWidth methods
+jQuery.each( { Height: "height", Width: "width" }, function( name, type ) {
+	jQuery.each( { padding: "inner" + name, content: type, "": "outer" + name },
+		function( defaultExtra, funcName ) {
+
+		// Margin is only for outerHeight, outerWidth
+		jQuery.fn[ funcName ] = function( margin, value ) {
+			var chainable = arguments.length && ( defaultExtra || typeof margin !== "boolean" ),
+				extra = defaultExtra || ( margin === true || value === true ? "margin" : "border" );
+
+			return access( this, function( elem, type, value ) {
+				var doc;
+
+				if ( jQuery.isWindow( elem ) ) {
+
+					// As of 5/8/2012 this will yield incorrect results for Mobile Safari, but there
+					// isn't a whole lot we can do. See pull request at this URL for discussion:
+					// https://github.com/jquery/jquery/pull/764
+					return elem.document.documentElement[ "client" + name ];
+				}
+
+				// Get document width or height
+				if ( elem.nodeType === 9 ) {
+					doc = elem.documentElement;
+
+					// Either scroll[Width/Height] or offset[Width/Height] or client[Width/Height],
+					// whichever is greatest
+					return Math.max(
+						elem.body[ "scroll" + name ], doc[ "scroll" + name ],
+						elem.body[ "offset" + name ], doc[ "offset" + name ],
+						doc[ "client" + name ]
+					);
+				}
+
+				return value === undefined ?
+
+					// Get width or height on the element, requesting but not forcing parseFloat
+					jQuery.css( elem, type, extra ) :
+
+					// Set width or height on the element
+					jQuery.style( elem, type, value, extra );
+			}, type, chainable ? margin : undefined, chainable, null );
+		};
+	} );
+} );
+
+
+jQuery.fn.extend( {
+
+	bind: function( types, data, fn ) {
+		return this.on( types, null, data, fn );
+	},
+	unbind: function( types, fn ) {
+		return this.off( types, null, fn );
+	},
+
+	delegate: function( selector, types, data, fn ) {
+		return this.on( types, selector, data, fn );
+	},
+	undelegate: function( selector, types, fn ) {
+
+		// ( namespace ) or ( selector, types [, fn] )
+		return arguments.length === 1 ?
+			this.off( selector, "**" ) :
+			this.off( types, selector || "**", fn );
+	},
+	size: function() {
+		return this.length;
+	}
+} );
+
+jQuery.fn.andSelf = jQuery.fn.addBack;
+
+
+
+
+// Register as a named AMD module, since jQuery can be concatenated with other
+// files that may use define, but not via a proper concatenation script that
+// understands anonymous AMD modules. A named AMD is safest and most robust
+// way to register. Lowercase jquery is used because AMD module names are
+// derived from file names, and jQuery is normally delivered in a lowercase
+// file name. Do this after creating the global so that if an AMD module wants
+// to call noConflict to hide this version of jQuery, it will work.
+
+// Note that for maximum portability, libraries that are not jQuery should
+// declare themselves as anonymous modules, and avoid setting a global if an
+// AMD loader is present. jQuery is a special case. For more information, see
+// https://github.com/jrburke/requirejs/wiki/Updating-existing-libraries#wiki-anon
+
+if ( typeof define === "function" && define.amd ) {
+	define( "jquery", [], function() {
+		return jQuery;
+	} );
+}
+
+
+
+var
+
+	// Map over jQuery in case of overwrite
+	_jQuery = window.jQuery,
+
+	// Map over the $ in case of overwrite
+	_$ = window.$;
+
+jQuery.noConflict = function( deep ) {
+	if ( window.$ === jQuery ) {
+		window.$ = _$;
+	}
+
+	if ( deep && window.jQuery === jQuery ) {
+		window.jQuery = _jQuery;
+	}
+
+	return jQuery;
+};
+
+// Expose jQuery and $ identifiers, even in AMD
+// (#7102#comment:10, https://github.com/jquery/jquery/pull/557)
+// and CommonJS for browser emulators (#13566)
+if ( !noGlobal ) {
+	window.jQuery = window.$ = jQuery;
+}
+
+return jQuery;
+}));
diff --git a/actionview/test/ujs/public/vendor/jquery.metadata.js b/actionview/test/ujs/public/vendor/jquery.metadata.js
new file mode 100644
index 0000000000..5b5253cdf7
--- /dev/null
+++ b/actionview/test/ujs/public/vendor/jquery.metadata.js
@@ -0,0 +1,122 @@
+/*
+ * Metadata - jQuery plugin for parsing metadata from elements
+ *
+ * Copyright (c) 2006 John Resig, Yehuda Katz, J�örn Zaefferer, Paul McLanahan
+ *
+ * Dual licensed under the MIT and GPL licenses:
+ *   http://www.opensource.org/licenses/mit-license.php
+ *   http://www.gnu.org/licenses/gpl.html
+ *
+ * Revision: $Id: jquery.metadata.js 4187 2007-12-16 17:15:27Z joern.zaefferer $
+ *
+ */
+
+/**
+ * Sets the type of metadata to use. Metadata is encoded in JSON, and each property
+ * in the JSON will become a property of the element itself.
+ *
+ * There are three supported types of metadata storage:
+ *
+ *   attr:  Inside an attribute. The name parameter indicates *which* attribute.
+ *          
+ *   class: Inside the class attribute, wrapped in curly braces: { }
+ *   
+ *   elem:  Inside a child element (e.g. a script tag). The
+ *          name parameter indicates *which* element.
+ *          
+ * The metadata for an element is loaded the first time the element is accessed via jQuery.
+ *
+ * As a result, you can define the metadata type, use $(expr) to load the metadata into the elements
+ * matched by expr, then redefine the metadata type and run another $(expr) for other elements.
+ * 
+ * @name $.metadata.setType
+ *
+ * @example <p id="one" class="some_class {item_id: 1, item_label: 'Label'}">This is a p</p>
+ * @before $.metadata.setType("class")
+ * @after $("#one").metadata().item_id == 1; $("#one").metadata().item_label == "Label"
+ * @desc Reads metadata from the class attribute
+ * 
+ * @example <p id="one" class="some_class" data="{item_id: 1, item_label: 'Label'}">This is a p</p>
+ * @before $.metadata.setType("attr", "data")
+ * @after $("#one").metadata().item_id == 1; $("#one").metadata().item_label == "Label"
+ * @desc Reads metadata from a "data" attribute
+ * 
+ * @example <p id="one" class="some_class"><script>{item_id: 1, item_label: 'Label'}</script>This is a p</p>
+ * @before $.metadata.setType("elem", "script")
+ * @after $("#one").metadata().item_id == 1; $("#one").metadata().item_label == "Label"
+ * @desc Reads metadata from a nested script element
+ * 
+ * @param String type The encoding type
+ * @param String name The name of the attribute to be used to get metadata (optional)
+ * @cat Plugins/Metadata
+ * @descr Sets the type of encoding to be used when loading metadata for the first time
+ * @type undefined
+ * @see metadata()
+ */
+
+(function($) {
+
+$.extend({
+	metadata : {
+		defaults : {
+			type: 'class',
+			name: 'metadata',
+			cre: /({.*})/,
+			single: 'metadata'
+		},
+		setType: function( type, name ){
+			this.defaults.type = type;
+			this.defaults.name = name;
+		},
+		get: function( elem, opts ){
+			var settings = $.extend({},this.defaults,opts);
+			// check for empty string in single property
+			if ( !settings.single.length ) settings.single = 'metadata';
+			
+			var data = $.data(elem, settings.single);
+			// returned cached data if it already exists
+			if ( data ) return data;
+			
+			data = "{}";
+			
+			if ( settings.type == "class" ) {
+				var m = settings.cre.exec( elem.className );
+				if ( m )
+					data = m[1];
+			} else if ( settings.type == "elem" ) {
+				if( !elem.getElementsByTagName )
+					return undefined;
+				var e = elem.getElementsByTagName(settings.name);
+				if ( e.length )
+					data = $.trim(e[0].innerHTML);
+			} else if ( elem.getAttribute != undefined ) {
+				var attr = elem.getAttribute( settings.name );
+				if ( attr )
+					data = attr;
+			}
+			
+			if ( data.indexOf( '{' ) <0 )
+			data = "{" + data + "}";
+			
+			data = eval("(" + data + ")");
+			
+			$.data( elem, settings.single, data );
+			return data;
+		}
+	}
+});
+
+/**
+ * Returns the metadata object for the first member of the jQuery object.
+ *
+ * @name metadata
+ * @descr Returns element's metadata object
+ * @param Object opts An object containing settings to override the defaults
+ * @type jQuery
+ * @cat Plugins/Metadata
+ */
+$.fn.metadata = function( opts ){
+	return $.metadata.get( this[0], opts );
+};
+
+})(jQuery);
\ No newline at end of file
diff --git a/actionview/test/ujs/public/vendor/qunit.css b/actionview/test/ujs/public/vendor/qunit.css
new file mode 100644
index 0000000000..93026e3ba3
--- /dev/null
+++ b/actionview/test/ujs/public/vendor/qunit.css
@@ -0,0 +1,237 @@
+/*!
+ * QUnit 1.14.0
+ * http://qunitjs.com/
+ *
+ * Copyright 2013 jQuery Foundation and other contributors
+ * Released under the MIT license
+ * http://jquery.org/license
+ *
+ * Date: 2014-01-31T16:40Z
+ */
+
+/** Font Family and Sizes */
+
+#qunit-tests, #qunit-header, #qunit-banner, #qunit-testrunner-toolbar, #qunit-userAgent, #qunit-testresult {
+	font-family: "Helvetica Neue Light", "HelveticaNeue-Light", "Helvetica Neue", Calibri, Helvetica, Arial, sans-serif;
+}
+
+#qunit-testrunner-toolbar, #qunit-userAgent, #qunit-testresult, #qunit-tests li { font-size: small; }
+#qunit-tests { font-size: smaller; }
+
+
+/** Resets */
+
+#qunit-tests, #qunit-header, #qunit-banner, #qunit-userAgent, #qunit-testresult, #qunit-modulefilter {
+	margin: 0;
+	padding: 0;
+}
+
+
+/** Header */
+
+#qunit-header {
+	padding: 0.5em 0 0.5em 1em;
+
+	color: #8699A4;
+	background-color: #0D3349;
+
+	font-size: 1.5em;
+	line-height: 1em;
+	font-weight: 400;
+
+	border-radius: 5px 5px 0 0;
+}
+
+#qunit-header a {
+	text-decoration: none;
+	color: #C2CCD1;
+}
+
+#qunit-header a:hover,
+#qunit-header a:focus {
+	color: #FFF;
+}
+
+#qunit-testrunner-toolbar label {
+	display: inline-block;
+	padding: 0 0.5em 0 0.1em;
+}
+
+#qunit-banner {
+	height: 5px;
+}
+
+#qunit-testrunner-toolbar {
+	padding: 0.5em 0 0.5em 2em;
+	color: #5E740B;
+	background-color: #EEE;
+	overflow: hidden;
+}
+
+#qunit-userAgent {
+	padding: 0.5em 0 0.5em 2.5em;
+	background-color: #2B81AF;
+	color: #FFF;
+	text-shadow: rgba(0, 0, 0, 0.5) 2px 2px 1px;
+}
+
+#qunit-modulefilter-container {
+	float: right;
+}
+
+/** Tests: Pass/Fail */
+
+#qunit-tests {
+	list-style-position: inside;
+}
+
+#qunit-tests li {
+	padding: 0.4em 0.5em 0.4em 2.5em;
+	border-bottom: 1px solid #FFF;
+	list-style-position: inside;
+}
+
+#qunit-tests.hidepass li.pass, #qunit-tests.hidepass li.running  {
+	display: none;
+}
+
+#qunit-tests li strong {
+	cursor: pointer;
+}
+
+#qunit-tests li a {
+	padding: 0.5em;
+	color: #C2CCD1;
+	text-decoration: none;
+}
+#qunit-tests li a:hover,
+#qunit-tests li a:focus {
+	color: #000;
+}
+
+#qunit-tests li .runtime {
+	float: right;
+	font-size: smaller;
+}
+
+.qunit-assert-list {
+	margin-top: 0.5em;
+	padding: 0.5em;
+
+	background-color: #FFF;
+
+	border-radius: 5px;
+}
+
+.qunit-collapsed {
+	display: none;
+}
+
+#qunit-tests table {
+	border-collapse: collapse;
+	margin-top: 0.2em;
+}
+
+#qunit-tests th {
+	text-align: right;
+	vertical-align: top;
+	padding: 0 0.5em 0 0;
+}
+
+#qunit-tests td {
+	vertical-align: top;
+}
+
+#qunit-tests pre {
+	margin: 0;
+	white-space: pre-wrap;
+	word-wrap: break-word;
+}
+
+#qunit-tests del {
+	background-color: #E0F2BE;
+	color: #374E0C;
+	text-decoration: none;
+}
+
+#qunit-tests ins {
+	background-color: #FFCACA;
+	color: #500;
+	text-decoration: none;
+}
+
+/*** Test Counts */
+
+#qunit-tests b.counts                       { color: #000; }
+#qunit-tests b.passed                       { color: #5E740B; }
+#qunit-tests b.failed                       { color: #710909; }
+
+#qunit-tests li li {
+	padding: 5px;
+	background-color: #FFF;
+	border-bottom: none;
+	list-style-position: inside;
+}
+
+/*** Passing Styles */
+
+#qunit-tests li li.pass {
+	color: #3C510C;
+	background-color: #FFF;
+	border-left: 10px solid #C6E746;
+}
+
+#qunit-tests .pass                          { color: #528CE0; background-color: #D2E0E6; }
+#qunit-tests .pass .test-name               { color: #366097; }
+
+#qunit-tests .pass .test-actual,
+#qunit-tests .pass .test-expected           { color: #999; }
+
+#qunit-banner.qunit-pass                    { background-color: #C6E746; }
+
+/*** Failing Styles */
+
+#qunit-tests li li.fail {
+	color: #710909;
+	background-color: #FFF;
+	border-left: 10px solid #EE5757;
+	white-space: pre;
+}
+
+#qunit-tests > li:last-child {
+	border-radius: 0 0 5px 5px;
+}
+
+#qunit-tests .fail                          { color: #000; background-color: #EE5757; }
+#qunit-tests .fail .test-name,
+#qunit-tests .fail .module-name             { color: #000; }
+
+#qunit-tests .fail .test-actual             { color: #EE5757; }
+#qunit-tests .fail .test-expected           { color: #008000; }
+
+#qunit-banner.qunit-fail                    { background-color: #EE5757; }
+
+
+/** Result */
+
+#qunit-testresult {
+	padding: 0.5em 0.5em 0.5em 2.5em;
+
+	color: #2B81AF;
+	background-color: #D2E0E6;
+
+	border-bottom: 1px solid #FFF;
+}
+#qunit-testresult .module-name {
+	font-weight: 700;
+}
+
+/** Fixture */
+
+#qunit-fixture {
+	position: absolute;
+	top: -10000px;
+	left: -10000px;
+	width: 1000px;
+	height: 1000px;
+}
diff --git a/actionview/test/ujs/public/vendor/qunit.js b/actionview/test/ujs/public/vendor/qunit.js
new file mode 100644
index 0000000000..50a9e6455d
--- /dev/null
+++ b/actionview/test/ujs/public/vendor/qunit.js
@@ -0,0 +1,2288 @@
+/*!
+ * QUnit 1.14.0
+ * http://qunitjs.com/
+ *
+ * Copyright 2013 jQuery Foundation and other contributors
+ * Released under the MIT license
+ * http://jquery.org/license
+ *
+ * Date: 2014-01-31T16:40Z
+ */
+
+(function( window ) {
+
+var QUnit,
+	assert,
+	config,
+	onErrorFnPrev,
+	testId = 0,
+	fileName = (sourceFromStacktrace( 0 ) || "" ).replace(/(:\d+)+\)?/, "").replace(/.+\//, ""),
+	toString = Object.prototype.toString,
+	hasOwn = Object.prototype.hasOwnProperty,
+	// Keep a local reference to Date (GH-283)
+	Date = window.Date,
+	setTimeout = window.setTimeout,
+	clearTimeout = window.clearTimeout,
+	defined = {
+		document: typeof window.document !== "undefined",
+		setTimeout: typeof window.setTimeout !== "undefined",
+		sessionStorage: (function() {
+			var x = "qunit-test-string";
+			try {
+				sessionStorage.setItem( x, x );
+				sessionStorage.removeItem( x );
+				return true;
+			} catch( e ) {
+				return false;
+			}
+		}())
+	},
+	/**
+	 * Provides a normalized error string, correcting an issue
+	 * with IE 7 (and prior) where Error.prototype.toString is
+	 * not properly implemented
+	 *
+	 * Based on https://es5.github.io/#x15.11.4.4
+	 *
+	 * @param {String|Error} error
+	 * @return {String} error message
+	 */
+	errorString = function( error ) {
+		var name, message,
+			errorString = error.toString();
+		if ( errorString.substring( 0, 7 ) === "[object" ) {
+			name = error.name ? error.name.toString() : "Error";
+			message = error.message ? error.message.toString() : "";
+			if ( name && message ) {
+				return name + ": " + message;
+			} else if ( name ) {
+				return name;
+			} else if ( message ) {
+				return message;
+			} else {
+				return "Error";
+			}
+		} else {
+			return errorString;
+		}
+	},
+	/**
+	 * Makes a clone of an object using only Array or Object as base,
+	 * and copies over the own enumerable properties.
+	 *
+	 * @param {Object} obj
+	 * @return {Object} New object with only the own properties (recursively).
+	 */
+	objectValues = function( obj ) {
+		// Grunt 0.3.x uses an older version of jshint that still has jshint/jshint#392.
+		/*jshint newcap: false */
+		var key, val,
+			vals = QUnit.is( "array", obj ) ? [] : {};
+		for ( key in obj ) {
+			if ( hasOwn.call( obj, key ) ) {
+				val = obj[key];
+				vals[key] = val === Object(val) ? objectValues(val) : val;
+			}
+		}
+		return vals;
+	};
+
+
+// Root QUnit object.
+// `QUnit` initialized at top of scope
+QUnit = {
+
+	// call on start of module test to prepend name to all tests
+	module: function( name, testEnvironment ) {
+		config.currentModule = name;
+		config.currentModuleTestEnvironment = testEnvironment;
+		config.modules[name] = true;
+	},
+
+	asyncTest: function( testName, expected, callback ) {
+		if ( arguments.length === 2 ) {
+			callback = expected;
+			expected = null;
+		}
+
+		QUnit.test( testName, expected, callback, true );
+	},
+
+	test: function( testName, expected, callback, async ) {
+		var test,
+			nameHtml = "<span class='test-name'>" + escapeText( testName ) + "</span>";
+
+		if ( arguments.length === 2 ) {
+			callback = expected;
+			expected = null;
+		}
+
+		if ( config.currentModule ) {
+			nameHtml = "<span class='module-name'>" + escapeText( config.currentModule ) + "</span>: " + nameHtml;
+		}
+
+		test = new Test({
+			nameHtml: nameHtml,
+			testName: testName,
+			expected: expected,
+			async: async,
+			callback: callback,
+			module: config.currentModule,
+			moduleTestEnvironment: config.currentModuleTestEnvironment,
+			stack: sourceFromStacktrace( 2 )
+		});
+
+		if ( !validTest( test ) ) {
+			return;
+		}
+
+		test.queue();
+	},
+
+	// Specify the number of expected assertions to guarantee that failed test (no assertions are run at all) don't slip through.
+	expect: function( asserts ) {
+		if (arguments.length === 1) {
+			config.current.expected = asserts;
+		} else {
+			return config.current.expected;
+		}
+	},
+
+	start: function( count ) {
+		// QUnit hasn't been initialized yet.
+		// Note: RequireJS (et al) may delay onLoad
+		if ( config.semaphore === undefined ) {
+			QUnit.begin(function() {
+				// This is triggered at the top of QUnit.load, push start() to the event loop, to allow QUnit.load to finish first
+				setTimeout(function() {
+					QUnit.start( count );
+				});
+			});
+			return;
+		}
+
+		config.semaphore -= count || 1;
+		// don't start until equal number of stop-calls
+		if ( config.semaphore > 0 ) {
+			return;
+		}
+		// ignore if start is called more often then stop
+		if ( config.semaphore < 0 ) {
+			config.semaphore = 0;
+			QUnit.pushFailure( "Called start() while already started (QUnit.config.semaphore was 0 already)", null, sourceFromStacktrace(2) );
+			return;
+		}
+		// A slight delay, to avoid any current callbacks
+		if ( defined.setTimeout ) {
+			setTimeout(function() {
+				if ( config.semaphore > 0 ) {
+					return;
+				}
+				if ( config.timeout ) {
+					clearTimeout( config.timeout );
+				}
+
+				config.blocking = false;
+				process( true );
+			}, 13);
+		} else {
+			config.blocking = false;
+			process( true );
+		}
+	},
+
+	stop: function( count ) {
+		config.semaphore += count || 1;
+		config.blocking = true;
+
+		if ( config.testTimeout && defined.setTimeout ) {
+			clearTimeout( config.timeout );
+			config.timeout = setTimeout(function() {
+				QUnit.ok( false, "Test timed out" );
+				config.semaphore = 1;
+				QUnit.start();
+			}, config.testTimeout );
+		}
+	}
+};
+
+// We use the prototype to distinguish between properties that should
+// be exposed as globals (and in exports) and those that shouldn't
+(function() {
+	function F() {}
+	F.prototype = QUnit;
+	QUnit = new F();
+	// Make F QUnit's constructor so that we can add to the prototype later
+	QUnit.constructor = F;
+}());
+
+/**
+ * Config object: Maintain internal state
+ * Later exposed as QUnit.config
+ * `config` initialized at top of scope
+ */
+config = {
+	// The queue of tests to run
+	queue: [],
+
+	// block until document ready
+	blocking: true,
+
+	// when enabled, show only failing tests
+	// gets persisted through sessionStorage and can be changed in UI via checkbox
+	hidepassed: false,
+
+	// by default, run previously failed tests first
+	// very useful in combination with "Hide passed tests" checked
+	reorder: true,
+
+	// by default, modify document.title when suite is done
+	altertitle: true,
+
+	// by default, scroll to top of the page when suite is done
+	scrolltop: true,
+
+	// when enabled, all tests must call expect()
+	requireExpects: false,
+
+	// add checkboxes that are persisted in the query-string
+	// when enabled, the id is set to `true` as a `QUnit.config` property
+	urlConfig: [
+		{
+			id: "noglobals",
+			label: "Check for Globals",
+			tooltip: "Enabling this will test if any test introduces new properties on the `window` object. Stored as query-strings."
+		},
+		{
+			id: "notrycatch",
+			label: "No try-catch",
+			tooltip: "Enabling this will run tests outside of a try-catch block. Makes debugging exceptions in IE reasonable. Stored as query-strings."
+		}
+	],
+
+	// Set of all modules.
+	modules: {},
+
+	// logging callback queues
+	begin: [],
+	done: [],
+	log: [],
+	testStart: [],
+	testDone: [],
+	moduleStart: [],
+	moduleDone: []
+};
+
+// Initialize more QUnit.config and QUnit.urlParams
+(function() {
+	var i, current,
+		location = window.location || { search: "", protocol: "file:" },
+		params = location.search.slice( 1 ).split( "&" ),
+		length = params.length,
+		urlParams = {};
+
+	if ( params[ 0 ] ) {
+		for ( i = 0; i < length; i++ ) {
+			current = params[ i ].split( "=" );
+			current[ 0 ] = decodeURIComponent( current[ 0 ] );
+
+			// allow just a key to turn on a flag, e.g., test.html?noglobals
+			current[ 1 ] = current[ 1 ] ? decodeURIComponent( current[ 1 ] ) : true;
+			if ( urlParams[ current[ 0 ] ] ) {
+				urlParams[ current[ 0 ] ] = [].concat( urlParams[ current[ 0 ] ], current[ 1 ] );
+			} else {
+				urlParams[ current[ 0 ] ] = current[ 1 ];
+			}
+		}
+	}
+
+	QUnit.urlParams = urlParams;
+
+	// String search anywhere in moduleName+testName
+	config.filter = urlParams.filter;
+
+	// Exact match of the module name
+	config.module = urlParams.module;
+
+	config.testNumber = [];
+	if ( urlParams.testNumber ) {
+
+		// Ensure that urlParams.testNumber is an array
+		urlParams.testNumber = [].concat( urlParams.testNumber );
+		for ( i = 0; i < urlParams.testNumber.length; i++ ) {
+			current = urlParams.testNumber[ i ];
+			config.testNumber.push( parseInt( current, 10 ) );
+		}
+	}
+
+	// Figure out if we're running the tests from a server or not
+	QUnit.isLocal = location.protocol === "file:";
+}());
+
+extend( QUnit, {
+
+	config: config,
+
+	// Initialize the configuration options
+	init: function() {
+		extend( config, {
+			stats: { all: 0, bad: 0 },
+			moduleStats: { all: 0, bad: 0 },
+			started: +new Date(),
+			updateRate: 1000,
+			blocking: false,
+			autostart: true,
+			autorun: false,
+			filter: "",
+			queue: [],
+			semaphore: 1
+		});
+
+		var tests, banner, result,
+			qunit = id( "qunit" );
+
+		if ( qunit ) {
+			qunit.innerHTML =
+				"<h1 id='qunit-header'>" + escapeText( document.title ) + "</h1>" +
+				"<h2 id='qunit-banner'></h2>" +
+				"<div id='qunit-testrunner-toolbar'></div>" +
+				"<h2 id='qunit-userAgent'></h2>" +
+				"<ol id='qunit-tests'></ol>";
+		}
+
+		tests = id( "qunit-tests" );
+		banner = id( "qunit-banner" );
+		result = id( "qunit-testresult" );
+
+		if ( tests ) {
+			tests.innerHTML = "";
+		}
+
+		if ( banner ) {
+			banner.className = "";
+		}
+
+		if ( result ) {
+			result.parentNode.removeChild( result );
+		}
+
+		if ( tests ) {
+			result = document.createElement( "p" );
+			result.id = "qunit-testresult";
+			result.className = "result";
+			tests.parentNode.insertBefore( result, tests );
+			result.innerHTML = "Running...<br/>&nbsp;";
+		}
+	},
+
+	// Resets the test setup. Useful for tests that modify the DOM.
+	/*
+	DEPRECATED: Use multiple tests instead of resetting inside a test.
+	Use testStart or testDone for custom cleanup.
+	This method will throw an error in 2.0, and will be removed in 2.1
+	*/
+	reset: function() {
+		var fixture = id( "qunit-fixture" );
+		if ( fixture ) {
+			fixture.innerHTML = config.fixture;
+		}
+	},
+
+	// Safe object type checking
+	is: function( type, obj ) {
+		return QUnit.objectType( obj ) === type;
+	},
+
+	objectType: function( obj ) {
+		if ( typeof obj === "undefined" ) {
+			return "undefined";
+		}
+
+		// Consider: typeof null === object
+		if ( obj === null ) {
+			return "null";
+		}
+
+		var match = toString.call( obj ).match(/^\[object\s(.*)\]$/),
+			type = match && match[1] || "";
+
+		switch ( type ) {
+			case "Number":
+				if ( isNaN(obj) ) {
+					return "nan";
+				}
+				return "number";
+			case "String":
+			case "Boolean":
+			case "Array":
+			case "Date":
+			case "RegExp":
+			case "Function":
+				return type.toLowerCase();
+		}
+		if ( typeof obj === "object" ) {
+			return "object";
+		}
+		return undefined;
+	},
+
+	push: function( result, actual, expected, message ) {
+		if ( !config.current ) {
+			throw new Error( "assertion outside test context, was " + sourceFromStacktrace() );
+		}
+
+		var output, source,
+			details = {
+				module: config.current.module,
+				name: config.current.testName,
+				result: result,
+				message: message,
+				actual: actual,
+				expected: expected
+			};
+
+		message = escapeText( message ) || ( result ? "okay" : "failed" );
+		message = "<span class='test-message'>" + message + "</span>";
+		output = message;
+
+		if ( !result ) {
+			expected = escapeText( QUnit.jsDump.parse(expected) );
+			actual = escapeText( QUnit.jsDump.parse(actual) );
+			output += "<table><tr class='test-expected'><th>Expected: </th><td><pre>" + expected + "</pre></td></tr>";
+
+			if ( actual !== expected ) {
+				output += "<tr class='test-actual'><th>Result: </th><td><pre>" + actual + "</pre></td></tr>";
+				output += "<tr class='test-diff'><th>Diff: </th><td><pre>" + QUnit.diff( expected, actual ) + "</pre></td></tr>";
+			}
+
+			source = sourceFromStacktrace();
+
+			if ( source ) {
+				details.source = source;
+				output += "<tr class='test-source'><th>Source: </th><td><pre>" + escapeText( source ) + "</pre></td></tr>";
+			}
+
+			output += "</table>";
+		}
+
+		runLoggingCallbacks( "log", QUnit, details );
+
+		config.current.assertions.push({
+			result: !!result,
+			message: output
+		});
+	},
+
+	pushFailure: function( message, source, actual ) {
+		if ( !config.current ) {
+			throw new Error( "pushFailure() assertion outside test context, was " + sourceFromStacktrace(2) );
+		}
+
+		var output,
+			details = {
+				module: config.current.module,
+				name: config.current.testName,
+				result: false,
+				message: message
+			};
+
+		message = escapeText( message ) || "error";
+		message = "<span class='test-message'>" + message + "</span>";
+		output = message;
+
+		output += "<table>";
+
+		if ( actual ) {
+			output += "<tr class='test-actual'><th>Result: </th><td><pre>" + escapeText( actual ) + "</pre></td></tr>";
+		}
+
+		if ( source ) {
+			details.source = source;
+			output += "<tr class='test-source'><th>Source: </th><td><pre>" + escapeText( source ) + "</pre></td></tr>";
+		}
+
+		output += "</table>";
+
+		runLoggingCallbacks( "log", QUnit, details );
+
+		config.current.assertions.push({
+			result: false,
+			message: output
+		});
+	},
+
+	url: function( params ) {
+		params = extend( extend( {}, QUnit.urlParams ), params );
+		var key,
+			querystring = "?";
+
+		for ( key in params ) {
+			if ( hasOwn.call( params, key ) ) {
+				querystring += encodeURIComponent( key ) + "=" +
+					encodeURIComponent( params[ key ] ) + "&";
+			}
+		}
+		return window.location.protocol + "//" + window.location.host +
+			window.location.pathname + querystring.slice( 0, -1 );
+	},
+
+	extend: extend,
+	id: id,
+	addEvent: addEvent,
+	addClass: addClass,
+	hasClass: hasClass,
+	removeClass: removeClass
+	// load, equiv, jsDump, diff: Attached later
+});
+
+/**
+ * @deprecated: Created for backwards compatibility with test runner that set the hook function
+ * into QUnit.{hook}, instead of invoking it and passing the hook function.
+ * QUnit.constructor is set to the empty F() above so that we can add to it's prototype here.
+ * Doing this allows us to tell if the following methods have been overwritten on the actual
+ * QUnit object.
+ */
+extend( QUnit.constructor.prototype, {
+
+	// Logging callbacks; all receive a single argument with the listed properties
+	// run test/logs.html for any related changes
+	begin: registerLoggingCallback( "begin" ),
+
+	// done: { failed, passed, total, runtime }
+	done: registerLoggingCallback( "done" ),
+
+	// log: { result, actual, expected, message }
+	log: registerLoggingCallback( "log" ),
+
+	// testStart: { name }
+	testStart: registerLoggingCallback( "testStart" ),
+
+	// testDone: { name, failed, passed, total, runtime }
+	testDone: registerLoggingCallback( "testDone" ),
+
+	// moduleStart: { name }
+	moduleStart: registerLoggingCallback( "moduleStart" ),
+
+	// moduleDone: { name, failed, passed, total }
+	moduleDone: registerLoggingCallback( "moduleDone" )
+});
+
+if ( !defined.document || document.readyState === "complete" ) {
+	config.autorun = true;
+}
+
+QUnit.load = function() {
+	runLoggingCallbacks( "begin", QUnit, {} );
+
+	// Initialize the config, saving the execution queue
+	var banner, filter, i, j, label, len, main, ol, toolbar, val, selection,
+		urlConfigContainer, moduleFilter, userAgent,
+		numModules = 0,
+		moduleNames = [],
+		moduleFilterHtml = "",
+		urlConfigHtml = "",
+		oldconfig = extend( {}, config );
+
+	QUnit.init();
+	extend(config, oldconfig);
+
+	config.blocking = false;
+
+	len = config.urlConfig.length;
+
+	for ( i = 0; i < len; i++ ) {
+		val = config.urlConfig[i];
+		if ( typeof val === "string" ) {
+			val = {
+				id: val,
+				label: val
+			};
+		}
+		config[ val.id ] = QUnit.urlParams[ val.id ];
+		if ( !val.value || typeof val.value === "string" ) {
+			urlConfigHtml += "<input id='qunit-urlconfig-" + escapeText( val.id ) +
+				"' name='" + escapeText( val.id ) +
+				"' type='checkbox'" +
+				( val.value ? " value='" + escapeText( val.value ) + "'" : "" ) +
+				( config[ val.id ] ? " checked='checked'" : "" ) +
+				" title='" + escapeText( val.tooltip ) +
+				"'><label for='qunit-urlconfig-" + escapeText( val.id ) +
+				"' title='" + escapeText( val.tooltip ) + "'>" + val.label + "</label>";
+		} else {
+			urlConfigHtml += "<label for='qunit-urlconfig-" + escapeText( val.id ) +
+				"' title='" + escapeText( val.tooltip ) +
+				"'>" + val.label +
+				": </label><select id='qunit-urlconfig-" + escapeText( val.id ) +
+				"' name='" + escapeText( val.id ) +
+				"' title='" + escapeText( val.tooltip ) +
+				"'><option></option>";
+			selection = false;
+			if ( QUnit.is( "array", val.value ) ) {
+				for ( j = 0; j < val.value.length; j++ ) {
+					urlConfigHtml += "<option value='" + escapeText( val.value[j] ) + "'" +
+						( config[ val.id ] === val.value[j] ?
+							(selection = true) && " selected='selected'" :
+							"" ) +
+						">" + escapeText( val.value[j] ) + "</option>";
+				}
+			} else {
+				for ( j in val.value ) {
+					if ( hasOwn.call( val.value, j ) ) {
+						urlConfigHtml += "<option value='" + escapeText( j ) + "'" +
+							( config[ val.id ] === j ?
+								(selection = true) && " selected='selected'" :
+								"" ) +
+							">" + escapeText( val.value[j] ) + "</option>";
+					}
+				}
+			}
+			if ( config[ val.id ] && !selection ) {
+				urlConfigHtml += "<option value='" + escapeText( config[ val.id ] ) +
+					"' selected='selected' disabled='disabled'>" +
+					escapeText( config[ val.id ] ) +
+					"</option>";
+			}
+			urlConfigHtml += "</select>";
+		}
+	}
+	for ( i in config.modules ) {
+		if ( config.modules.hasOwnProperty( i ) ) {
+			moduleNames.push(i);
+		}
+	}
+	numModules = moduleNames.length;
+	moduleNames.sort( function( a, b ) {
+		return a.localeCompare( b );
+	});
+	moduleFilterHtml += "<label for='qunit-modulefilter'>Module: </label><select id='qunit-modulefilter' name='modulefilter'><option value='' " +
+		( config.module === undefined  ? "selected='selected'" : "" ) +
+		">< All Modules ></option>";
+
+
+	for ( i = 0; i < numModules; i++) {
+			moduleFilterHtml += "<option value='" + escapeText( encodeURIComponent(moduleNames[i]) ) + "' " +
+				( config.module === moduleNames[i] ? "selected='selected'" : "" ) +
+				">" + escapeText(moduleNames[i]) + "</option>";
+	}
+	moduleFilterHtml += "</select>";
+
+	// `userAgent` initialized at top of scope
+	userAgent = id( "qunit-userAgent" );
+	if ( userAgent ) {
+		userAgent.innerHTML = navigator.userAgent;
+	}
+
+	// `banner` initialized at top of scope
+	banner = id( "qunit-header" );
+	if ( banner ) {
+		banner.innerHTML = "<a href='" + QUnit.url({ filter: undefined, module: undefined, testNumber: undefined }) + "'>" + banner.innerHTML + "</a> ";
+	}
+
+	// `toolbar` initialized at top of scope
+	toolbar = id( "qunit-testrunner-toolbar" );
+	if ( toolbar ) {
+		// `filter` initialized at top of scope
+		filter = document.createElement( "input" );
+		filter.type = "checkbox";
+		filter.id = "qunit-filter-pass";
+
+		addEvent( filter, "click", function() {
+			var tmp,
+				ol = id( "qunit-tests" );
+
+			if ( filter.checked ) {
+				ol.className = ol.className + " hidepass";
+			} else {
+				tmp = " " + ol.className.replace( /[\n\t\r]/g, " " ) + " ";
+				ol.className = tmp.replace( / hidepass /, " " );
+			}
+			if ( defined.sessionStorage ) {
+				if (filter.checked) {
+					sessionStorage.setItem( "qunit-filter-passed-tests", "true" );
+				} else {
+					sessionStorage.removeItem( "qunit-filter-passed-tests" );
+				}
+			}
+		});
+
+		if ( config.hidepassed || defined.sessionStorage && sessionStorage.getItem( "qunit-filter-passed-tests" ) ) {
+			filter.checked = true;
+			// `ol` initialized at top of scope
+			ol = id( "qunit-tests" );
+			ol.className = ol.className + " hidepass";
+		}
+		toolbar.appendChild( filter );
+
+		// `label` initialized at top of scope
+		label = document.createElement( "label" );
+		label.setAttribute( "for", "qunit-filter-pass" );
+		label.setAttribute( "title", "Only show tests and assertions that fail. Stored in sessionStorage." );
+		label.innerHTML = "Hide passed tests";
+		toolbar.appendChild( label );
+
+		urlConfigContainer = document.createElement("span");
+		urlConfigContainer.innerHTML = urlConfigHtml;
+		// For oldIE support:
+		// * Add handlers to the individual elements instead of the container
+		// * Use "click" instead of "change" for checkboxes
+		// * Fallback from event.target to event.srcElement
+		addEvents( urlConfigContainer.getElementsByTagName("input"), "click", function( event ) {
+			var params = {},
+				target = event.target || event.srcElement;
+			params[ target.name ] = target.checked ?
+				target.defaultValue || true :
+				undefined;
+			window.location = QUnit.url( params );
+		});
+		addEvents( urlConfigContainer.getElementsByTagName("select"), "change", function( event ) {
+			var params = {},
+				target = event.target || event.srcElement;
+			params[ target.name ] = target.options[ target.selectedIndex ].value || undefined;
+			window.location = QUnit.url( params );
+		});
+		toolbar.appendChild( urlConfigContainer );
+
+		if (numModules > 1) {
+			moduleFilter = document.createElement( "span" );
+			moduleFilter.setAttribute( "id", "qunit-modulefilter-container" );
+			moduleFilter.innerHTML = moduleFilterHtml;
+			addEvent( moduleFilter.lastChild, "change", function() {
+				var selectBox = moduleFilter.getElementsByTagName("select")[0],
+					selectedModule = decodeURIComponent(selectBox.options[selectBox.selectedIndex].value);
+
+				window.location = QUnit.url({
+					module: ( selectedModule === "" ) ? undefined : selectedModule,
+					// Remove any existing filters
+					filter: undefined,
+					testNumber: undefined
+				});
+			});
+			toolbar.appendChild(moduleFilter);
+		}
+	}
+
+	// `main` initialized at top of scope
+	main = id( "qunit-fixture" );
+	if ( main ) {
+		config.fixture = main.innerHTML;
+	}
+
+	if ( config.autostart ) {
+		QUnit.start();
+	}
+};
+
+if ( defined.document ) {
+	addEvent( window, "load", QUnit.load );
+}
+
+// `onErrorFnPrev` initialized at top of scope
+// Preserve other handlers
+onErrorFnPrev = window.onerror;
+
+// Cover uncaught exceptions
+// Returning true will suppress the default browser handler,
+// returning false will let it run.
+window.onerror = function ( error, filePath, linerNr ) {
+	var ret = false;
+	if ( onErrorFnPrev ) {
+		ret = onErrorFnPrev( error, filePath, linerNr );
+	}
+
+	// Treat return value as window.onerror itself does,
+	// Only do our handling if not suppressed.
+	if ( ret !== true ) {
+		if ( QUnit.config.current ) {
+			if ( QUnit.config.current.ignoreGlobalErrors ) {
+				return true;
+			}
+			QUnit.pushFailure( error, filePath + ":" + linerNr );
+		} else {
+			QUnit.test( "global failure", extend( function() {
+				QUnit.pushFailure( error, filePath + ":" + linerNr );
+			}, { validTest: validTest } ) );
+		}
+		return false;
+	}
+
+	return ret;
+};
+
+function done() {
+	config.autorun = true;
+
+	// Log the last module results
+	if ( config.previousModule ) {
+		runLoggingCallbacks( "moduleDone", QUnit, {
+			name: config.previousModule,
+			failed: config.moduleStats.bad,
+			passed: config.moduleStats.all - config.moduleStats.bad,
+			total: config.moduleStats.all
+		});
+	}
+	delete config.previousModule;
+
+	var i, key,
+		banner = id( "qunit-banner" ),
+		tests = id( "qunit-tests" ),
+		runtime = +new Date() - config.started,
+		passed = config.stats.all - config.stats.bad,
+		html = [
+			"Tests completed in ",
+			runtime,
+			" milliseconds.<br/>",
+			"<span class='passed'>",
+			passed,
+			"</span> assertions of <span class='total'>",
+			config.stats.all,
+			"</span> passed, <span class='failed'>",
+			config.stats.bad,
+			"</span> failed."
+		].join( "" );
+
+	if ( banner ) {
+		banner.className = ( config.stats.bad ? "qunit-fail" : "qunit-pass" );
+	}
+
+	if ( tests ) {
+		id( "qunit-testresult" ).innerHTML = html;
+	}
+
+	if ( config.altertitle && defined.document && document.title ) {
+		// show ✖ for good, ✔ for bad suite result in title
+		// use escape sequences in case file gets loaded with non-utf-8-charset
+		document.title = [
+			( config.stats.bad ? "\u2716" : "\u2714" ),
+			document.title.replace( /^[\u2714\u2716] /i, "" )
+		].join( " " );
+	}
+
+	// clear own sessionStorage items if all tests passed
+	if ( config.reorder && defined.sessionStorage && config.stats.bad === 0 ) {
+		// `key` & `i` initialized at top of scope
+		for ( i = 0; i < sessionStorage.length; i++ ) {
+			key = sessionStorage.key( i++ );
+			if ( key.indexOf( "qunit-test-" ) === 0 ) {
+				sessionStorage.removeItem( key );
+			}
+		}
+	}
+
+	// scroll back to top to show results
+	if ( config.scrolltop && window.scrollTo ) {
+		window.scrollTo(0, 0);
+	}
+
+	runLoggingCallbacks( "done", QUnit, {
+		failed: config.stats.bad,
+		passed: passed,
+		total: config.stats.all,
+		runtime: runtime
+	});
+}
+
+/** @return Boolean: true if this test should be ran */
+function validTest( test ) {
+	var include,
+		filter = config.filter && config.filter.toLowerCase(),
+		module = config.module && config.module.toLowerCase(),
+		fullName = ( test.module + ": " + test.testName ).toLowerCase();
+
+	// Internally-generated tests are always valid
+	if ( test.callback && test.callback.validTest === validTest ) {
+		delete test.callback.validTest;
+		return true;
+	}
+
+	if ( config.testNumber.length > 0 ) {
+		if ( inArray( test.testNumber, config.testNumber ) < 0 ) {
+			return false;
+		}
+	}
+
+	if ( module && ( !test.module || test.module.toLowerCase() !== module ) ) {
+		return false;
+	}
+
+	if ( !filter ) {
+		return true;
+	}
+
+	include = filter.charAt( 0 ) !== "!";
+	if ( !include ) {
+		filter = filter.slice( 1 );
+	}
+
+	// If the filter matches, we need to honour include
+	if ( fullName.indexOf( filter ) !== -1 ) {
+		return include;
+	}
+
+	// Otherwise, do the opposite
+	return !include;
+}
+
+// so far supports only Firefox, Chrome and Opera (buggy), Safari (for real exceptions)
+// Later Safari and IE10 are supposed to support error.stack as well
+// See also https://developer.mozilla.org/en/JavaScript/Reference/Global_Objects/Error/Stack
+function extractStacktrace( e, offset ) {
+	offset = offset === undefined ? 3 : offset;
+
+	var stack, include, i;
+
+	if ( e.stacktrace ) {
+		// Opera
+		return e.stacktrace.split( "\n" )[ offset + 3 ];
+	} else if ( e.stack ) {
+		// Firefox, Chrome
+		stack = e.stack.split( "\n" );
+		if (/^error$/i.test( stack[0] ) ) {
+			stack.shift();
+		}
+		if ( fileName ) {
+			include = [];
+			for ( i = offset; i < stack.length; i++ ) {
+				if ( stack[ i ].indexOf( fileName ) !== -1 ) {
+					break;
+				}
+				include.push( stack[ i ] );
+			}
+			if ( include.length ) {
+				return include.join( "\n" );
+			}
+		}
+		return stack[ offset ];
+	} else if ( e.sourceURL ) {
+		// Safari, PhantomJS
+		// hopefully one day Safari provides actual stacktraces
+		// exclude useless self-reference for generated Error objects
+		if ( /qunit.js$/.test( e.sourceURL ) ) {
+			return;
+		}
+		// for actual exceptions, this is useful
+		return e.sourceURL + ":" + e.line;
+	}
+}
+function sourceFromStacktrace( offset ) {
+	try {
+		throw new Error();
+	} catch ( e ) {
+		return extractStacktrace( e, offset );
+	}
+}
+
+/**
+ * Escape text for attribute or text content.
+ */
+function escapeText( s ) {
+	if ( !s ) {
+		return "";
+	}
+	s = s + "";
+	// Both single quotes and double quotes (for attributes)
+	return s.replace( /['"<>&]/g, function( s ) {
+		switch( s ) {
+			case "'":
+				return "&#039;";
+			case "\"":
+				return "&quot;";
+			case "<":
+				return "&lt;";
+			case ">":
+				return "&gt;";
+			case "&":
+				return "&amp;";
+		}
+	});
+}
+
+function synchronize( callback, last ) {
+	config.queue.push( callback );
+
+	if ( config.autorun && !config.blocking ) {
+		process( last );
+	}
+}
+
+function process( last ) {
+	function next() {
+		process( last );
+	}
+	var start = new Date().getTime();
+	config.depth = config.depth ? config.depth + 1 : 1;
+
+	while ( config.queue.length && !config.blocking ) {
+		if ( !defined.setTimeout || config.updateRate <= 0 || ( ( new Date().getTime() - start ) < config.updateRate ) ) {
+			config.queue.shift()();
+		} else {
+			setTimeout( next, 13 );
+			break;
+		}
+	}
+	config.depth--;
+	if ( last && !config.blocking && !config.queue.length && config.depth === 0 ) {
+		done();
+	}
+}
+
+function saveGlobal() {
+	config.pollution = [];
+
+	if ( config.noglobals ) {
+		for ( var key in window ) {
+			if ( hasOwn.call( window, key ) ) {
+				// in Opera sometimes DOM element ids show up here, ignore them
+				if ( /^qunit-test-output/.test( key ) ) {
+					continue;
+				}
+				config.pollution.push( key );
+			}
+		}
+	}
+}
+
+function checkPollution() {
+	var newGlobals,
+		deletedGlobals,
+		old = config.pollution;
+
+	saveGlobal();
+
+	newGlobals = diff( config.pollution, old );
+	if ( newGlobals.length > 0 ) {
+		QUnit.pushFailure( "Introduced global variable(s): " + newGlobals.join(", ") );
+	}
+
+	deletedGlobals = diff( old, config.pollution );
+	if ( deletedGlobals.length > 0 ) {
+		QUnit.pushFailure( "Deleted global variable(s): " + deletedGlobals.join(", ") );
+	}
+}
+
+// returns a new Array with the elements that are in a but not in b
+function diff( a, b ) {
+	var i, j,
+		result = a.slice();
+
+	for ( i = 0; i < result.length; i++ ) {
+		for ( j = 0; j < b.length; j++ ) {
+			if ( result[i] === b[j] ) {
+				result.splice( i, 1 );
+				i--;
+				break;
+			}
+		}
+	}
+	return result;
+}
+
+function extend( a, b ) {
+	for ( var prop in b ) {
+		if ( hasOwn.call( b, prop ) ) {
+			// Avoid "Member not found" error in IE8 caused by messing with window.constructor
+			if ( !( prop === "constructor" && a === window ) ) {
+				if ( b[ prop ] === undefined ) {
+					delete a[ prop ];
+				} else {
+					a[ prop ] = b[ prop ];
+				}
+			}
+		}
+	}
+
+	return a;
+}
+
+/**
+ * @param {HTMLElement} elem
+ * @param {string} type
+ * @param {Function} fn
+ */
+function addEvent( elem, type, fn ) {
+	if ( elem.addEventListener ) {
+
+		// Standards-based browsers
+		elem.addEventListener( type, fn, false );
+	} else if ( elem.attachEvent ) {
+
+		// support: IE <9
+		elem.attachEvent( "on" + type, fn );
+	} else {
+
+		// Caller must ensure support for event listeners is present
+		throw new Error( "addEvent() was called in a context without event listener support" );
+	}
+}
+
+/**
+ * @param {Array|NodeList} elems
+ * @param {string} type
+ * @param {Function} fn
+ */
+function addEvents( elems, type, fn ) {
+	var i = elems.length;
+	while ( i-- ) {
+		addEvent( elems[i], type, fn );
+	}
+}
+
+function hasClass( elem, name ) {
+	return (" " + elem.className + " ").indexOf(" " + name + " ") > -1;
+}
+
+function addClass( elem, name ) {
+	if ( !hasClass( elem, name ) ) {
+		elem.className += (elem.className ? " " : "") + name;
+	}
+}
+
+function removeClass( elem, name ) {
+	var set = " " + elem.className + " ";
+	// Class name may appear multiple times
+	while ( set.indexOf(" " + name + " ") > -1 ) {
+		set = set.replace(" " + name + " " , " ");
+	}
+	// If possible, trim it for prettiness, but not necessarily
+	elem.className = typeof set.trim === "function" ? set.trim() : set.replace(/^\s+|\s+$/g, "");
+}
+
+function id( name ) {
+	return defined.document && document.getElementById && document.getElementById( name );
+}
+
+function registerLoggingCallback( key ) {
+	return function( callback ) {
+		config[key].push( callback );
+	};
+}
+
+// Supports deprecated method of completely overwriting logging callbacks
+function runLoggingCallbacks( key, scope, args ) {
+	var i, callbacks;
+	if ( QUnit.hasOwnProperty( key ) ) {
+		QUnit[ key ].call(scope, args );
+	} else {
+		callbacks = config[ key ];
+		for ( i = 0; i < callbacks.length; i++ ) {
+			callbacks[ i ].call( scope, args );
+		}
+	}
+}
+
+// from jquery.js
+function inArray( elem, array ) {
+	if ( array.indexOf ) {
+		return array.indexOf( elem );
+	}
+
+	for ( var i = 0, length = array.length; i < length; i++ ) {
+		if ( array[ i ] === elem ) {
+			return i;
+		}
+	}
+
+	return -1;
+}
+
+function Test( settings ) {
+	extend( this, settings );
+	this.assertions = [];
+	this.testNumber = ++Test.count;
+}
+
+Test.count = 0;
+
+Test.prototype = {
+	init: function() {
+		var a, b, li,
+			tests = id( "qunit-tests" );
+
+		if ( tests ) {
+			b = document.createElement( "strong" );
+			b.innerHTML = this.nameHtml;
+
+			// `a` initialized at top of scope
+			a = document.createElement( "a" );
+			a.innerHTML = "Rerun";
+			a.href = QUnit.url({ testNumber: this.testNumber });
+
+			li = document.createElement( "li" );
+			li.appendChild( b );
+			li.appendChild( a );
+			li.className = "running";
+			li.id = this.id = "qunit-test-output" + testId++;
+
+			tests.appendChild( li );
+		}
+	},
+	setup: function() {
+		if (
+			// Emit moduleStart when we're switching from one module to another
+			this.module !== config.previousModule ||
+				// They could be equal (both undefined) but if the previousModule property doesn't
+				// yet exist it means this is the first test in a suite that isn't wrapped in a
+				// module, in which case we'll just emit a moduleStart event for 'undefined'.
+				// Without this, reporters can get testStart before moduleStart  which is a problem.
+				!hasOwn.call( config, "previousModule" )
+		) {
+			if ( hasOwn.call( config, "previousModule" ) ) {
+				runLoggingCallbacks( "moduleDone", QUnit, {
+					name: config.previousModule,
+					failed: config.moduleStats.bad,
+					passed: config.moduleStats.all - config.moduleStats.bad,
+					total: config.moduleStats.all
+				});
+			}
+			config.previousModule = this.module;
+			config.moduleStats = { all: 0, bad: 0 };
+			runLoggingCallbacks( "moduleStart", QUnit, {
+				name: this.module
+			});
+		}
+
+		config.current = this;
+
+		this.testEnvironment = extend({
+			setup: function() {},
+			teardown: function() {}
+		}, this.moduleTestEnvironment );
+
+		this.started = +new Date();
+		runLoggingCallbacks( "testStart", QUnit, {
+			name: this.testName,
+			module: this.module
+		});
+
+		/*jshint camelcase:false */
+
+
+		/**
+		 * Expose the current test environment.
+		 *
+		 * @deprecated since 1.12.0: Use QUnit.config.current.testEnvironment instead.
+		 */
+		QUnit.current_testEnvironment = this.testEnvironment;
+
+		/*jshint camelcase:true */
+
+		if ( !config.pollution ) {
+			saveGlobal();
+		}
+		if ( config.notrycatch ) {
+			this.testEnvironment.setup.call( this.testEnvironment, QUnit.assert );
+			return;
+		}
+		try {
+			this.testEnvironment.setup.call( this.testEnvironment, QUnit.assert );
+		} catch( e ) {
+			QUnit.pushFailure( "Setup failed on " + this.testName + ": " + ( e.message || e ), extractStacktrace( e, 1 ) );
+		}
+	},
+	run: function() {
+		config.current = this;
+
+		var running = id( "qunit-testresult" );
+
+		if ( running ) {
+			running.innerHTML = "Running: <br/>" + this.nameHtml;
+		}
+
+		if ( this.async ) {
+			QUnit.stop();
+		}
+
+		this.callbackStarted = +new Date();
+
+		if ( config.notrycatch ) {
+			this.callback.call( this.testEnvironment, QUnit.assert );
+			this.callbackRuntime = +new Date() - this.callbackStarted;
+			return;
+		}
+
+		try {
+			this.callback.call( this.testEnvironment, QUnit.assert );
+			this.callbackRuntime = +new Date() - this.callbackStarted;
+		} catch( e ) {
+			this.callbackRuntime = +new Date() - this.callbackStarted;
+
+			QUnit.pushFailure( "Died on test #" + (this.assertions.length + 1) + " " + this.stack + ": " + ( e.message || e ), extractStacktrace( e, 0 ) );
+			// else next test will carry the responsibility
+			saveGlobal();
+
+			// Restart the tests if they're blocking
+			if ( config.blocking ) {
+				QUnit.start();
+			}
+		}
+	},
+	teardown: function() {
+		config.current = this;
+		if ( config.notrycatch ) {
+			if ( typeof this.callbackRuntime === "undefined" ) {
+				this.callbackRuntime = +new Date() - this.callbackStarted;
+			}
+			this.testEnvironment.teardown.call( this.testEnvironment, QUnit.assert );
+			return;
+		} else {
+			try {
+				this.testEnvironment.teardown.call( this.testEnvironment, QUnit.assert );
+			} catch( e ) {
+				QUnit.pushFailure( "Teardown failed on " + this.testName + ": " + ( e.message || e ), extractStacktrace( e, 1 ) );
+			}
+		}
+		checkPollution();
+	},
+	finish: function() {
+		config.current = this;
+		if ( config.requireExpects && this.expected === null ) {
+			QUnit.pushFailure( "Expected number of assertions to be defined, but expect() was not called.", this.stack );
+		} else if ( this.expected !== null && this.expected !== this.assertions.length ) {
+			QUnit.pushFailure( "Expected " + this.expected + " assertions, but " + this.assertions.length + " were run", this.stack );
+		} else if ( this.expected === null && !this.assertions.length ) {
+			QUnit.pushFailure( "Expected at least one assertion, but none were run - call expect(0) to accept zero assertions.", this.stack );
+		}
+
+		var i, assertion, a, b, time, li, ol,
+			test = this,
+			good = 0,
+			bad = 0,
+			tests = id( "qunit-tests" );
+
+		this.runtime = +new Date() - this.started;
+		config.stats.all += this.assertions.length;
+		config.moduleStats.all += this.assertions.length;
+
+		if ( tests ) {
+			ol = document.createElement( "ol" );
+			ol.className = "qunit-assert-list";
+
+			for ( i = 0; i < this.assertions.length; i++ ) {
+				assertion = this.assertions[i];
+
+				li = document.createElement( "li" );
+				li.className = assertion.result ? "pass" : "fail";
+				li.innerHTML = assertion.message || ( assertion.result ? "okay" : "failed" );
+				ol.appendChild( li );
+
+				if ( assertion.result ) {
+					good++;
+				} else {
+					bad++;
+					config.stats.bad++;
+					config.moduleStats.bad++;
+				}
+			}
+
+			// store result when possible
+			if ( QUnit.config.reorder && defined.sessionStorage ) {
+				if ( bad ) {
+					sessionStorage.setItem( "qunit-test-" + this.module + "-" + this.testName, bad );
+				} else {
+					sessionStorage.removeItem( "qunit-test-" + this.module + "-" + this.testName );
+				}
+			}
+
+			if ( bad === 0 ) {
+				addClass( ol, "qunit-collapsed" );
+			}
+
+			// `b` initialized at top of scope
+			b = document.createElement( "strong" );
+			b.innerHTML = this.nameHtml + " <b class='counts'>(<b class='failed'>" + bad + "</b>, <b class='passed'>" + good + "</b>, " + this.assertions.length + ")</b>";
+
+			addEvent(b, "click", function() {
+				var next = b.parentNode.lastChild,
+					collapsed = hasClass( next, "qunit-collapsed" );
+				( collapsed ? removeClass : addClass )( next, "qunit-collapsed" );
+			});
+
+			addEvent(b, "dblclick", function( e ) {
+				var target = e && e.target ? e.target : window.event.srcElement;
+				if ( target.nodeName.toLowerCase() === "span" || target.nodeName.toLowerCase() === "b" ) {
+					target = target.parentNode;
+				}
+				if ( window.location && target.nodeName.toLowerCase() === "strong" ) {
+					window.location = QUnit.url({ testNumber: test.testNumber });
+				}
+			});
+
+			// `time` initialized at top of scope
+			time = document.createElement( "span" );
+			time.className = "runtime";
+			time.innerHTML = this.runtime + " ms";
+
+			// `li` initialized at top of scope
+			li = id( this.id );
+			li.className = bad ? "fail" : "pass";
+			li.removeChild( li.firstChild );
+			a = li.firstChild;
+			li.appendChild( b );
+			li.appendChild( a );
+			li.appendChild( time );
+			li.appendChild( ol );
+
+		} else {
+			for ( i = 0; i < this.assertions.length; i++ ) {
+				if ( !this.assertions[i].result ) {
+					bad++;
+					config.stats.bad++;
+					config.moduleStats.bad++;
+				}
+			}
+		}
+
+		runLoggingCallbacks( "testDone", QUnit, {
+			name: this.testName,
+			module: this.module,
+			failed: bad,
+			passed: this.assertions.length - bad,
+			total: this.assertions.length,
+			runtime: this.runtime,
+			// DEPRECATED: this property will be removed in 2.0.0, use runtime instead
+			duration: this.runtime
+		});
+
+		QUnit.reset();
+
+		config.current = undefined;
+	},
+
+	queue: function() {
+		var bad,
+			test = this;
+
+		synchronize(function() {
+			test.init();
+		});
+		function run() {
+			// each of these can by async
+			synchronize(function() {
+				test.setup();
+			});
+			synchronize(function() {
+				test.run();
+			});
+			synchronize(function() {
+				test.teardown();
+			});
+			synchronize(function() {
+				test.finish();
+			});
+		}
+
+		// `bad` initialized at top of scope
+		// defer when previous test run passed, if storage is available
+		bad = QUnit.config.reorder && defined.sessionStorage &&
+						+sessionStorage.getItem( "qunit-test-" + this.module + "-" + this.testName );
+
+		if ( bad ) {
+			run();
+		} else {
+			synchronize( run, true );
+		}
+	}
+};
+
+// `assert` initialized at top of scope
+// Assert helpers
+// All of these must either call QUnit.push() or manually do:
+// - runLoggingCallbacks( "log", .. );
+// - config.current.assertions.push({ .. });
+assert = QUnit.assert = {
+	/**
+	 * Asserts rough true-ish result.
+	 * @name ok
+	 * @function
+	 * @example ok( "asdfasdf".length > 5, "There must be at least 5 chars" );
+	 */
+	ok: function( result, msg ) {
+		if ( !config.current ) {
+			throw new Error( "ok() assertion outside test context, was " + sourceFromStacktrace(2) );
+		}
+		result = !!result;
+		msg = msg || ( result ? "okay" : "failed" );
+
+		var source,
+			details = {
+				module: config.current.module,
+				name: config.current.testName,
+				result: result,
+				message: msg
+			};
+
+		msg = "<span class='test-message'>" + escapeText( msg ) + "</span>";
+
+		if ( !result ) {
+			source = sourceFromStacktrace( 2 );
+			if ( source ) {
+				details.source = source;
+				msg += "<table><tr class='test-source'><th>Source: </th><td><pre>" +
+					escapeText( source ) +
+					"</pre></td></tr></table>";
+			}
+		}
+		runLoggingCallbacks( "log", QUnit, details );
+		config.current.assertions.push({
+			result: result,
+			message: msg
+		});
+	},
+
+	/**
+	 * Assert that the first two arguments are equal, with an optional message.
+	 * Prints out both actual and expected values.
+	 * @name equal
+	 * @function
+	 * @example equal( format( "Received {0} bytes.", 2), "Received 2 bytes.", "format() replaces {0} with next argument" );
+	 */
+	equal: function( actual, expected, message ) {
+		/*jshint eqeqeq:false */
+		QUnit.push( expected == actual, actual, expected, message );
+	},
+
+	/**
+	 * @name notEqual
+	 * @function
+	 */
+	notEqual: function( actual, expected, message ) {
+		/*jshint eqeqeq:false */
+		QUnit.push( expected != actual, actual, expected, message );
+	},
+
+	/**
+	 * @name propEqual
+	 * @function
+	 */
+	propEqual: function( actual, expected, message ) {
+		actual = objectValues(actual);
+		expected = objectValues(expected);
+		QUnit.push( QUnit.equiv(actual, expected), actual, expected, message );
+	},
+
+	/**
+	 * @name notPropEqual
+	 * @function
+	 */
+	notPropEqual: function( actual, expected, message ) {
+		actual = objectValues(actual);
+		expected = objectValues(expected);
+		QUnit.push( !QUnit.equiv(actual, expected), actual, expected, message );
+	},
+
+	/**
+	 * @name deepEqual
+	 * @function
+	 */
+	deepEqual: function( actual, expected, message ) {
+		QUnit.push( QUnit.equiv(actual, expected), actual, expected, message );
+	},
+
+	/**
+	 * @name notDeepEqual
+	 * @function
+	 */
+	notDeepEqual: function( actual, expected, message ) {
+		QUnit.push( !QUnit.equiv(actual, expected), actual, expected, message );
+	},
+
+	/**
+	 * @name strictEqual
+	 * @function
+	 */
+	strictEqual: function( actual, expected, message ) {
+		QUnit.push( expected === actual, actual, expected, message );
+	},
+
+	/**
+	 * @name notStrictEqual
+	 * @function
+	 */
+	notStrictEqual: function( actual, expected, message ) {
+		QUnit.push( expected !== actual, actual, expected, message );
+	},
+
+	"throws": function( block, expected, message ) {
+		var actual,
+			expectedOutput = expected,
+			ok = false;
+
+		// 'expected' is optional
+		if ( !message && typeof expected === "string" ) {
+			message = expected;
+			expected = null;
+		}
+
+		config.current.ignoreGlobalErrors = true;
+		try {
+			block.call( config.current.testEnvironment );
+		} catch (e) {
+			actual = e;
+		}
+		config.current.ignoreGlobalErrors = false;
+
+		if ( actual ) {
+
+			// we don't want to validate thrown error
+			if ( !expected ) {
+				ok = true;
+				expectedOutput = null;
+
+			// expected is an Error object
+			} else if ( expected instanceof Error ) {
+				ok = actual instanceof Error &&
+					 actual.name === expected.name &&
+					 actual.message === expected.message;
+
+			// expected is a regexp
+			} else if ( QUnit.objectType( expected ) === "regexp" ) {
+				ok = expected.test( errorString( actual ) );
+
+			// expected is a string
+			} else if ( QUnit.objectType( expected ) === "string" ) {
+				ok = expected === errorString( actual );
+
+			// expected is a constructor
+			} else if ( actual instanceof expected ) {
+				ok = true;
+
+			// expected is a validation function which returns true is validation passed
+			} else if ( expected.call( {}, actual ) === true ) {
+				expectedOutput = null;
+				ok = true;
+			}
+
+			QUnit.push( ok, actual, expectedOutput, message );
+		} else {
+			QUnit.pushFailure( message, null, "No exception was thrown." );
+		}
+	}
+};
+
+/**
+ * @deprecated since 1.8.0
+ * Kept assertion helpers in root for backwards compatibility.
+ */
+extend( QUnit.constructor.prototype, assert );
+
+/**
+ * @deprecated since 1.9.0
+ * Kept to avoid TypeErrors for undefined methods.
+ */
+QUnit.constructor.prototype.raises = function() {
+	QUnit.push( false, false, false, "QUnit.raises has been deprecated since 2012 (fad3c1ea), use QUnit.throws instead" );
+};
+
+/**
+ * @deprecated since 1.0.0, replaced with error pushes since 1.3.0
+ * Kept to avoid TypeErrors for undefined methods.
+ */
+QUnit.constructor.prototype.equals = function() {
+	QUnit.push( false, false, false, "QUnit.equals has been deprecated since 2009 (e88049a0), use QUnit.equal instead" );
+};
+QUnit.constructor.prototype.same = function() {
+	QUnit.push( false, false, false, "QUnit.same has been deprecated since 2009 (e88049a0), use QUnit.deepEqual instead" );
+};
+
+// Test for equality any JavaScript type.
+// Author: Philippe Rathé <prathe@gmail.com>
+QUnit.equiv = (function() {
+
+	// Call the o related callback with the given arguments.
+	function bindCallbacks( o, callbacks, args ) {
+		var prop = QUnit.objectType( o );
+		if ( prop ) {
+			if ( QUnit.objectType( callbacks[ prop ] ) === "function" ) {
+				return callbacks[ prop ].apply( callbacks, args );
+			} else {
+				return callbacks[ prop ]; // or undefined
+			}
+		}
+	}
+
+	// the real equiv function
+	var innerEquiv,
+		// stack to decide between skip/abort functions
+		callers = [],
+		// stack to avoiding loops from circular referencing
+		parents = [],
+		parentsB = [],
+
+		getProto = Object.getPrototypeOf || function ( obj ) {
+			/*jshint camelcase:false */
+			return obj.__proto__;
+		},
+		callbacks = (function () {
+
+			// for string, boolean, number and null
+			function useStrictEquality( b, a ) {
+				/*jshint eqeqeq:false */
+				if ( b instanceof a.constructor || a instanceof b.constructor ) {
+					// to catch short annotation VS 'new' annotation of a
+					// declaration
+					// e.g. var i = 1;
+					// var j = new Number(1);
+					return a == b;
+				} else {
+					return a === b;
+				}
+			}
+
+			return {
+				"string": useStrictEquality,
+				"boolean": useStrictEquality,
+				"number": useStrictEquality,
+				"null": useStrictEquality,
+				"undefined": useStrictEquality,
+
+				"nan": function( b ) {
+					return isNaN( b );
+				},
+
+				"date": function( b, a ) {
+					return QUnit.objectType( b ) === "date" && a.valueOf() === b.valueOf();
+				},
+
+				"regexp": function( b, a ) {
+					return QUnit.objectType( b ) === "regexp" &&
+						// the regex itself
+						a.source === b.source &&
+						// and its modifiers
+						a.global === b.global &&
+						// (gmi) ...
+						a.ignoreCase === b.ignoreCase &&
+						a.multiline === b.multiline &&
+						a.sticky === b.sticky;
+				},
+
+				// - skip when the property is a method of an instance (OOP)
+				// - abort otherwise,
+				// initial === would have catch identical references anyway
+				"function": function() {
+					var caller = callers[callers.length - 1];
+					return caller !== Object && typeof caller !== "undefined";
+				},
+
+				"array": function( b, a ) {
+					var i, j, len, loop, aCircular, bCircular;
+
+					// b could be an object literal here
+					if ( QUnit.objectType( b ) !== "array" ) {
+						return false;
+					}
+
+					len = a.length;
+					if ( len !== b.length ) {
+						// safe and faster
+						return false;
+					}
+
+					// track reference to avoid circular references
+					parents.push( a );
+					parentsB.push( b );
+					for ( i = 0; i < len; i++ ) {
+						loop = false;
+						for ( j = 0; j < parents.length; j++ ) {
+							aCircular = parents[j] === a[i];
+							bCircular = parentsB[j] === b[i];
+							if ( aCircular || bCircular ) {
+								if ( a[i] === b[i] || aCircular && bCircular ) {
+									loop = true;
+								} else {
+									parents.pop();
+									parentsB.pop();
+									return false;
+								}
+							}
+						}
+						if ( !loop && !innerEquiv(a[i], b[i]) ) {
+							parents.pop();
+							parentsB.pop();
+							return false;
+						}
+					}
+					parents.pop();
+					parentsB.pop();
+					return true;
+				},
+
+				"object": function( b, a ) {
+					/*jshint forin:false */
+					var i, j, loop, aCircular, bCircular,
+						// Default to true
+						eq = true,
+						aProperties = [],
+						bProperties = [];
+
+					// comparing constructors is more strict than using
+					// instanceof
+					if ( a.constructor !== b.constructor ) {
+						// Allow objects with no prototype to be equivalent to
+						// objects with Object as their constructor.
+						if ( !(( getProto(a) === null && getProto(b) === Object.prototype ) ||
+							( getProto(b) === null && getProto(a) === Object.prototype ) ) ) {
+								return false;
+						}
+					}
+
+					// stack constructor before traversing properties
+					callers.push( a.constructor );
+
+					// track reference to avoid circular references
+					parents.push( a );
+					parentsB.push( b );
+
+					// be strict: don't ensure hasOwnProperty and go deep
+					for ( i in a ) {
+						loop = false;
+						for ( j = 0; j < parents.length; j++ ) {
+							aCircular = parents[j] === a[i];
+							bCircular = parentsB[j] === b[i];
+							if ( aCircular || bCircular ) {
+								if ( a[i] === b[i] || aCircular && bCircular ) {
+									loop = true;
+								} else {
+									eq = false;
+									break;
+								}
+							}
+						}
+						aProperties.push(i);
+						if ( !loop && !innerEquiv(a[i], b[i]) ) {
+							eq = false;
+							break;
+						}
+					}
+
+					parents.pop();
+					parentsB.pop();
+					callers.pop(); // unstack, we are done
+
+					for ( i in b ) {
+						bProperties.push( i ); // collect b's properties
+					}
+
+					// Ensures identical properties name
+					return eq && innerEquiv( aProperties.sort(), bProperties.sort() );
+				}
+			};
+		}());
+
+	innerEquiv = function() { // can take multiple arguments
+		var args = [].slice.apply( arguments );
+		if ( args.length < 2 ) {
+			return true; // end transition
+		}
+
+		return (function( a, b ) {
+			if ( a === b ) {
+				return true; // catch the most you can
+			} else if ( a === null || b === null || typeof a === "undefined" ||
+					typeof b === "undefined" ||
+					QUnit.objectType(a) !== QUnit.objectType(b) ) {
+				return false; // don't lose time with error prone cases
+			} else {
+				return bindCallbacks(a, callbacks, [ b, a ]);
+			}
+
+			// apply transition with (1..n) arguments
+		}( args[0], args[1] ) && innerEquiv.apply( this, args.splice(1, args.length - 1 )) );
+	};
+
+	return innerEquiv;
+}());
+
+/**
+ * jsDump Copyright (c) 2008 Ariel Flesler - aflesler(at)gmail(dot)com |
+ * http://flesler.blogspot.com Licensed under BSD
+ * (http://www.opensource.org/licenses/bsd-license.php) Date: 5/15/2008
+ *
+ * @projectDescription Advanced and extensible data dumping for Javascript.
+ * @version 1.0.0
+ * @author Ariel Flesler
+ * @link {http://flesler.blogspot.com/2008/05/jsdump-pretty-dump-of-any-javascript.html}
+ */
+QUnit.jsDump = (function() {
+	function quote( str ) {
+		return "\"" + str.toString().replace( /"/g, "\\\"" ) + "\"";
+	}
+	function literal( o ) {
+		return o + "";
+	}
+	function join( pre, arr, post ) {
+		var s = jsDump.separator(),
+			base = jsDump.indent(),
+			inner = jsDump.indent(1);
+		if ( arr.join ) {
+			arr = arr.join( "," + s + inner );
+		}
+		if ( !arr ) {
+			return pre + post;
+		}
+		return [ pre, inner + arr, base + post ].join(s);
+	}
+	function array( arr, stack ) {
+		var i = arr.length, ret = new Array(i);
+		this.up();
+		while ( i-- ) {
+			ret[i] = this.parse( arr[i] , undefined , stack);
+		}
+		this.down();
+		return join( "[", ret, "]" );
+	}
+
+	var reName = /^function (\w+)/,
+		jsDump = {
+			// type is used mostly internally, you can fix a (custom)type in advance
+			parse: function( obj, type, stack ) {
+				stack = stack || [ ];
+				var inStack, res,
+					parser = this.parsers[ type || this.typeOf(obj) ];
+
+				type = typeof parser;
+				inStack = inArray( obj, stack );
+
+				if ( inStack !== -1 ) {
+					return "recursion(" + (inStack - stack.length) + ")";
+				}
+				if ( type === "function" )  {
+					stack.push( obj );
+					res = parser.call( this, obj, stack );
+					stack.pop();
+					return res;
+				}
+				return ( type === "string" ) ? parser : this.parsers.error;
+			},
+			typeOf: function( obj ) {
+				var type;
+				if ( obj === null ) {
+					type = "null";
+				} else if ( typeof obj === "undefined" ) {
+					type = "undefined";
+				} else if ( QUnit.is( "regexp", obj) ) {
+					type = "regexp";
+				} else if ( QUnit.is( "date", obj) ) {
+					type = "date";
+				} else if ( QUnit.is( "function", obj) ) {
+					type = "function";
+				} else if ( typeof obj.setInterval !== undefined && typeof obj.document !== "undefined" && typeof obj.nodeType === "undefined" ) {
+					type = "window";
+				} else if ( obj.nodeType === 9 ) {
+					type = "document";
+				} else if ( obj.nodeType ) {
+					type = "node";
+				} else if (
+					// native arrays
+					toString.call( obj ) === "[object Array]" ||
+					// NodeList objects
+					( typeof obj.length === "number" && typeof obj.item !== "undefined" && ( obj.length ? obj.item(0) === obj[0] : ( obj.item( 0 ) === null && typeof obj[0] === "undefined" ) ) )
+				) {
+					type = "array";
+				} else if ( obj.constructor === Error.prototype.constructor ) {
+					type = "error";
+				} else {
+					type = typeof obj;
+				}
+				return type;
+			},
+			separator: function() {
+				return this.multiline ?	this.HTML ? "<br />" : "\n" : this.HTML ? "&nbsp;" : " ";
+			},
+			// extra can be a number, shortcut for increasing-calling-decreasing
+			indent: function( extra ) {
+				if ( !this.multiline ) {
+					return "";
+				}
+				var chr = this.indentChar;
+				if ( this.HTML ) {
+					chr = chr.replace( /\t/g, "   " ).replace( / /g, "&nbsp;" );
+				}
+				return new Array( this.depth + ( extra || 0 ) ).join(chr);
+			},
+			up: function( a ) {
+				this.depth += a || 1;
+			},
+			down: function( a ) {
+				this.depth -= a || 1;
+			},
+			setParser: function( name, parser ) {
+				this.parsers[name] = parser;
+			},
+			// The next 3 are exposed so you can use them
+			quote: quote,
+			literal: literal,
+			join: join,
+			//
+			depth: 1,
+			// This is the list of parsers, to modify them, use jsDump.setParser
+			parsers: {
+				window: "[Window]",
+				document: "[Document]",
+				error: function(error) {
+					return "Error(\"" + error.message + "\")";
+				},
+				unknown: "[Unknown]",
+				"null": "null",
+				"undefined": "undefined",
+				"function": function( fn ) {
+					var ret = "function",
+						// functions never have name in IE
+						name = "name" in fn ? fn.name : (reName.exec(fn) || [])[1];
+
+					if ( name ) {
+						ret += " " + name;
+					}
+					ret += "( ";
+
+					ret = [ ret, QUnit.jsDump.parse( fn, "functionArgs" ), "){" ].join( "" );
+					return join( ret, QUnit.jsDump.parse(fn,"functionCode" ), "}" );
+				},
+				array: array,
+				nodelist: array,
+				"arguments": array,
+				object: function( map, stack ) {
+					/*jshint forin:false */
+					var ret = [ ], keys, key, val, i;
+					QUnit.jsDump.up();
+					keys = [];
+					for ( key in map ) {
+						keys.push( key );
+					}
+					keys.sort();
+					for ( i = 0; i < keys.length; i++ ) {
+						key = keys[ i ];
+						val = map[ key ];
+						ret.push( QUnit.jsDump.parse( key, "key" ) + ": " + QUnit.jsDump.parse( val, undefined, stack ) );
+					}
+					QUnit.jsDump.down();
+					return join( "{", ret, "}" );
+				},
+				node: function( node ) {
+					var len, i, val,
+						open = QUnit.jsDump.HTML ? "&lt;" : "<",
+						close = QUnit.jsDump.HTML ? "&gt;" : ">",
+						tag = node.nodeName.toLowerCase(),
+						ret = open + tag,
+						attrs = node.attributes;
+
+					if ( attrs ) {
+						for ( i = 0, len = attrs.length; i < len; i++ ) {
+							val = attrs[i].nodeValue;
+							// IE6 includes all attributes in .attributes, even ones not explicitly set.
+							// Those have values like undefined, null, 0, false, "" or "inherit".
+							if ( val && val !== "inherit" ) {
+								ret += " " + attrs[i].nodeName + "=" + QUnit.jsDump.parse( val, "attribute" );
+							}
+						}
+					}
+					ret += close;
+
+					// Show content of TextNode or CDATASection
+					if ( node.nodeType === 3 || node.nodeType === 4 ) {
+						ret += node.nodeValue;
+					}
+
+					return ret + open + "/" + tag + close;
+				},
+				// function calls it internally, it's the arguments part of the function
+				functionArgs: function( fn ) {
+					var args,
+						l = fn.length;
+
+					if ( !l ) {
+						return "";
+					}
+
+					args = new Array(l);
+					while ( l-- ) {
+						// 97 is 'a'
+						args[l] = String.fromCharCode(97+l);
+					}
+					return " " + args.join( ", " ) + " ";
+				},
+				// object calls it internally, the key part of an item in a map
+				key: quote,
+				// function calls it internally, it's the content of the function
+				functionCode: "[code]",
+				// node calls it internally, it's an html attribute value
+				attribute: quote,
+				string: quote,
+				date: quote,
+				regexp: literal,
+				number: literal,
+				"boolean": literal
+			},
+			// if true, entities are escaped ( <, >, \t, space and \n )
+			HTML: false,
+			// indentation unit
+			indentChar: "  ",
+			// if true, items in a collection, are separated by a \n, else just a space.
+			multiline: true
+		};
+
+	return jsDump;
+}());
+
+/*
+ * Javascript Diff Algorithm
+ *  By John Resig (http://ejohn.org/)
+ *  Modified by Chu Alan "sprite"
+ *
+ * Released under the MIT license.
+ *
+ * More Info:
+ *  http://ejohn.org/projects/javascript-diff-algorithm/
+ *
+ * Usage: QUnit.diff(expected, actual)
+ *
+ * QUnit.diff( "the quick brown fox jumped over", "the quick fox jumps over" ) == "the  quick <del>brown </del> fox <del>jumped </del><ins>jumps </ins> over"
+ */
+QUnit.diff = (function() {
+	/*jshint eqeqeq:false, eqnull:true */
+	function diff( o, n ) {
+		var i,
+			ns = {},
+			os = {};
+
+		for ( i = 0; i < n.length; i++ ) {
+			if ( !hasOwn.call( ns, n[i] ) ) {
+				ns[ n[i] ] = {
+					rows: [],
+					o: null
+				};
+			}
+			ns[ n[i] ].rows.push( i );
+		}
+
+		for ( i = 0; i < o.length; i++ ) {
+			if ( !hasOwn.call( os, o[i] ) ) {
+				os[ o[i] ] = {
+					rows: [],
+					n: null
+				};
+			}
+			os[ o[i] ].rows.push( i );
+		}
+
+		for ( i in ns ) {
+			if ( hasOwn.call( ns, i ) ) {
+				if ( ns[i].rows.length === 1 && hasOwn.call( os, i ) && os[i].rows.length === 1 ) {
+					n[ ns[i].rows[0] ] = {
+						text: n[ ns[i].rows[0] ],
+						row: os[i].rows[0]
+					};
+					o[ os[i].rows[0] ] = {
+						text: o[ os[i].rows[0] ],
+						row: ns[i].rows[0]
+					};
+				}
+			}
+		}
+
+		for ( i = 0; i < n.length - 1; i++ ) {
+			if ( n[i].text != null && n[ i + 1 ].text == null && n[i].row + 1 < o.length && o[ n[i].row + 1 ].text == null &&
+						n[ i + 1 ] == o[ n[i].row + 1 ] ) {
+
+				n[ i + 1 ] = {
+					text: n[ i + 1 ],
+					row: n[i].row + 1
+				};
+				o[ n[i].row + 1 ] = {
+					text: o[ n[i].row + 1 ],
+					row: i + 1
+				};
+			}
+		}
+
+		for ( i = n.length - 1; i > 0; i-- ) {
+			if ( n[i].text != null && n[ i - 1 ].text == null && n[i].row > 0 && o[ n[i].row - 1 ].text == null &&
+						n[ i - 1 ] == o[ n[i].row - 1 ]) {
+
+				n[ i - 1 ] = {
+					text: n[ i - 1 ],
+					row: n[i].row - 1
+				};
+				o[ n[i].row - 1 ] = {
+					text: o[ n[i].row - 1 ],
+					row: i - 1
+				};
+			}
+		}
+
+		return {
+			o: o,
+			n: n
+		};
+	}
+
+	return function( o, n ) {
+		o = o.replace( /\s+$/, "" );
+		n = n.replace( /\s+$/, "" );
+
+		var i, pre,
+			str = "",
+			out = diff( o === "" ? [] : o.split(/\s+/), n === "" ? [] : n.split(/\s+/) ),
+			oSpace = o.match(/\s+/g),
+			nSpace = n.match(/\s+/g);
+
+		if ( oSpace == null ) {
+			oSpace = [ " " ];
+		}
+		else {
+			oSpace.push( " " );
+		}
+
+		if ( nSpace == null ) {
+			nSpace = [ " " ];
+		}
+		else {
+			nSpace.push( " " );
+		}
+
+		if ( out.n.length === 0 ) {
+			for ( i = 0; i < out.o.length; i++ ) {
+				str += "<del>" + out.o[i] + oSpace[i] + "</del>";
+			}
+		}
+		else {
+			if ( out.n[0].text == null ) {
+				for ( n = 0; n < out.o.length && out.o[n].text == null; n++ ) {
+					str += "<del>" + out.o[n] + oSpace[n] + "</del>";
+				}
+			}
+
+			for ( i = 0; i < out.n.length; i++ ) {
+				if (out.n[i].text == null) {
+					str += "<ins>" + out.n[i] + nSpace[i] + "</ins>";
+				}
+				else {
+					// `pre` initialized at top of scope
+					pre = "";
+
+					for ( n = out.n[i].row + 1; n < out.o.length && out.o[n].text == null; n++ ) {
+						pre += "<del>" + out.o[n] + oSpace[n] + "</del>";
+					}
+					str += " " + out.n[i].text + nSpace[i] + pre;
+				}
+			}
+		}
+
+		return str;
+	};
+}());
+
+// For browser, export only select globals
+if ( typeof window !== "undefined" ) {
+	extend( window, QUnit.constructor.prototype );
+	window.QUnit = QUnit;
+}
+
+// For CommonJS environments, export everything
+if ( typeof module !== "undefined" && module.exports ) {
+	module.exports = QUnit;
+}
+
+
+// Get a reference to the global object, like window in browsers
+}( (function() {
+	return this;
+})() ));
diff --git a/actionview/test/ujs/server.rb b/actionview/test/ujs/server.rb
new file mode 100644
index 0000000000..7d1bab4b2a
--- /dev/null
+++ b/actionview/test/ujs/server.rb
@@ -0,0 +1,74 @@
+# frozen_string_literal: true
+
+require "rack"
+require "rails"
+require "action_controller/railtie"
+require "action_view/railtie"
+require "blade"
+require "json"
+
+module UJS
+  class Server < Rails::Application
+    routes.append do
+      get "/rails-ujs.js" => Blade::Assets.environment
+      get "/" => "tests#index"
+      match "/echo" => "tests#echo", via: :all
+      get "/error" => proc { |env| [403, {}, []] }
+    end
+
+    config.cache_classes = false
+    config.eager_load = false
+    config.secret_key_base = "59d7a4dbd349fa3838d79e330e39690fc22b931e7dc17d9162f03d633d526fbb92dfdb2dc9804c8be3e199631b9c1fbe43fc3e4fc75730b515851849c728d5c7"
+    config.paths["app/views"].unshift("#{Rails.root}/views")
+    config.public_file_server.enabled = true
+    config.logger = Logger.new(STDOUT)
+    config.log_level = :error
+  end
+end
+
+module TestsHelper
+  def test_to(*names)
+    names = ["/vendor/qunit.js", "settings"] + names
+    names.map { |name| script_tag name }.join("\n").html_safe
+  end
+
+  def script_tag(src)
+    src = "/test/#{src}.js" unless src.index("/")
+    %(<script src="#{src}" type="text/javascript"></script>).html_safe
+  end
+end
+
+class TestsController < ActionController::Base
+  helper TestsHelper
+  layout "application"
+
+  def index
+    render :index
+  end
+
+  def echo
+    data = { params: params.to_unsafe_h }.update(request.env)
+
+    if params[:content_type] && params[:content]
+      render inline: params[:content], content_type: params[:content_type]
+    elsif request.xhr?
+      render json: JSON.generate(data)
+    elsif params[:iframe]
+      payload = JSON.generate(data).gsub("<", "&lt;").gsub(">", "&gt;")
+      html = <<-HTML
+        <script>
+          if (window.top && window.top !== window)
+            window.top.jQuery.event.trigger('iframe:loaded', #{payload})
+        </script>
+        <p>You shouldn't be seeing this. <a href="#{request.env['HTTP_REFERER']}">Go back</a></p>
+      HTML
+
+      render html: html.html_safe
+    else
+      render plain: "ERROR: #{request.path} requested without ajax", status: 404
+    end
+  end
+end
+
+Blade.initialize!
+UJS::Server.initialize!
diff --git a/actionview/test/ujs/views/layouts/application.html.erb b/actionview/test/ujs/views/layouts/application.html.erb
new file mode 100644
index 0000000000..c787e77b84
--- /dev/null
+++ b/actionview/test/ujs/views/layouts/application.html.erb
@@ -0,0 +1,25 @@
+<!DOCTYPE html>
+<html id="html">
+  <head>
+    <title><%= @title %></title>
+    <link href="/vendor/qunit.css" media="screen" rel="stylesheet" type="text/css" media="screen, projection" />
+    <script src="/vendor/jquery-2.2.0.js" type="text/javascript"></script>
+    <script>
+      // This is for test in override.js.
+      // Must go before rails-ujs.
+      document.addEventListener('rails:attachBindings', function() {
+        window.Rails.linkClickSelector += ', a[data-custom-remote-link]';
+        // Hijacks link click before ujs binds any handlers
+        // This is only used for ctrl-clicking test on remote links
+        window.Rails.delegate(document, '#qunit-fixture a', 'click', function(e) {
+          e.preventDefault();
+        });
+      });
+    </script>
+    <%= script_tag "/rails-ujs.js" %>
+  </head>
+
+  <body id="body">
+    <%= yield %>
+  </body>
+</html>
diff --git a/actionview/test/ujs/views/tests/index.html.erb b/actionview/test/ujs/views/tests/index.html.erb
new file mode 100644
index 0000000000..6b16535216
--- /dev/null
+++ b/actionview/test/ujs/views/tests/index.html.erb
@@ -0,0 +1,11 @@
+<% @title = "rails-ujs test" %>
+
+<%= test_to 'data-confirm', 'data-remote', 'data-disable', 'data-disable-with', 'call-remote', 'call-remote-callbacks', 'data-method', 'override', 'csrf-refresh', 'csrf-token', 'call-ajax' %>
+
+<h1 id="qunit-header"><%= @title %></h1>
+<h2 id="qunit-banner"></h2>
+<div id="qunit-testrunner-toolbar"></div>
+<h2 id="qunit-userAgent"></h2>
+<ol id="qunit-tests"></ol>
+
+<div id="qunit-fixture"></div>
diff --git a/activejob/.gitignore b/activejob/.gitignore
deleted file mode 100644
index b3aaf55871..0000000000
--- a/activejob/.gitignore
+++ /dev/null
@@ -1 +0,0 @@
-test/dummy
diff --git a/activejob/CHANGELOG.md b/activejob/CHANGELOG.md
index 5e72c67aea..4453f845f4 100644
--- a/activejob/CHANGELOG.md
+++ b/activejob/CHANGELOG.md
@@ -1,2 +1,12 @@
+## Rails 5.2.0.beta2 (November 28, 2017) ##
 
-Please check [5-0-stable](https://github.com/rails/rails/blob/5-0-stable/activejob/CHANGELOG.md) for previous changes.
+*   No changes.
+
+
+## Rails 5.2.0.beta1 (November 27, 2017) ##
+
+*   Support redis-rb 4.0.
+
+    *Jeremy Daer*
+
+Please check [5-1-stable](https://github.com/rails/rails/blob/5-1-stable/activejob/CHANGELOG.md) for previous changes.
diff --git a/activejob/MIT-LICENSE b/activejob/MIT-LICENSE
index a3ffb46b3f..274211f710 100644
--- a/activejob/MIT-LICENSE
+++ b/activejob/MIT-LICENSE
@@ -1,4 +1,4 @@
-Copyright (c) 2014-2016 David Heinemeier Hansson
+Copyright (c) 2014-2018 David Heinemeier Hansson
 
 Permission is hereby granted, free of charge, to any person obtaining
 a copy of this software and associated documentation files (the
diff --git a/activejob/README.md b/activejob/README.md
index 8becac7753..f1ebb76e08 100644
--- a/activejob/README.md
+++ b/activejob/README.md
@@ -100,7 +100,7 @@ The latest version of Active Job can be installed with RubyGems:
   $ gem install activejob
 ```
 
-Source code can be downloaded as part of the Rails project on GitHub
+Source code can be downloaded as part of the Rails project on GitHub:
 
 * https://github.com/rails/rails/tree/master/activejob
 
@@ -108,7 +108,7 @@ Source code can be downloaded as part of the Rails project on GitHub
 
 Active Job is released under the MIT license:
 
-* http://www.opensource.org/licenses/MIT
+* https://opensource.org/licenses/MIT
 
 
 ## Support
@@ -117,7 +117,7 @@ API documentation is at:
 
 * http://api.rubyonrails.org
 
-Bug reports can be filed for the Ruby on Rails project here:
+Bug reports for the Ruby on Rails project can be filed here:
 
 * https://github.com/rails/rails/issues
 
diff --git a/activejob/Rakefile b/activejob/Rakefile
index e47f17b740..77f3e7f8ff 100644
--- a/activejob/Rakefile
+++ b/activejob/Rakefile
@@ -1,41 +1,43 @@
-require 'rake/testtask'
+# frozen_string_literal: true
 
-#TODO: add qu back to the list after it support Rails 5.1
+require "rake/testtask"
+
+# TODO: add qu back to the list after it support Rails 5.1
 ACTIVEJOB_ADAPTERS = %w(async inline delayed_job que queue_classic resque sidekiq sneakers sucker_punch backburner test)
-ACTIVEJOB_ADAPTERS -= %w(queue_classic) if defined?(JRUBY_VERSION)
+ACTIVEJOB_ADAPTERS.delete("queue_classic") if defined?(JRUBY_VERSION)
 
 task default: :test
-task test: 'test:default'
+task test: "test:default"
 
 task :package
 
 namespace :test do
-  desc 'Run all adapter tests'
+  desc "Run all adapter tests"
   task :default do
     run_without_aborting ACTIVEJOB_ADAPTERS.map { |a| "test:#{a}" }
   end
 
-  desc 'Run all adapter tests in isolation'
+  desc "Run all adapter tests in isolation"
   task :isolated do
     run_without_aborting ACTIVEJOB_ADAPTERS.map { |a| "test:isolated:#{a}" }
   end
 
-  desc 'Run integration tests for all adapters'
+  desc "Run integration tests for all adapters"
   task :integration do
-    run_without_aborting (ACTIVEJOB_ADAPTERS - ['test']).map { |a| "test:integration:#{a}" }
+    run_without_aborting (ACTIVEJOB_ADAPTERS - ["test"]).map { |a| "test:integration:#{a}" }
   end
 
-  task 'env:integration' do
-    ENV['AJ_INTEGRATION_TESTS'] = "1"
+  task "env:integration" do
+    ENV["AJ_INTEGRATION_TESTS"] = "1"
   end
 
   ACTIVEJOB_ADAPTERS.each do |adapter|
-    task("env:#{adapter}") { ENV['AJ_ADAPTER'] = adapter }
+    task("env:#{adapter}") { ENV["AJ_ADAPTER"] = adapter }
 
     Rake::TestTask.new(adapter => "test:env:#{adapter}") do |t|
       t.description = "Run adapter tests for #{adapter}"
-      t.libs << 'test'
-      t.test_files = FileList['test/cases/**/*_test.rb']
+      t.libs << "test"
+      t.test_files = FileList["test/cases/**/*_test.rb"]
       t.verbose = true
       t.warning = false
       t.ruby_opts = ["--dev"] if defined?(JRUBY_VERSION)
@@ -43,18 +45,17 @@ namespace :test do
 
     namespace :isolated do
       task adapter => "test:env:#{adapter}" do
-        dir = File.dirname(__FILE__)
-        Dir.glob("#{dir}/test/cases/**/*_test.rb").all? do |file|
-          sh(Gem.ruby, '-w', "-I#{dir}/lib", "-I#{dir}/test", file)
-        end or raise 'Failures'
+        Dir.glob("#{__dir__}/test/cases/**/*_test.rb").all? do |file|
+          sh(Gem.ruby, "-w", "-I#{__dir__}/lib", "-I#{__dir__}/test", file)
+        end || raise("Failures")
       end
     end
 
     namespace :integration do
-      Rake::TestTask.new(adapter => ["test:env:#{adapter}", 'test:env:integration']) do |t|
+      Rake::TestTask.new(adapter => ["test:env:#{adapter}", "test:env:integration"]) do |t|
         t.description = "Run integration tests for #{adapter}"
-        t.libs << 'test'
-        t.test_files = FileList['test/integration/**/*_test.rb']
+        t.libs << "test"
+        t.test_files = FileList["test/integration/**/*_test.rb"]
         t.verbose = true
         t.warning = false
         t.ruby_opts = ["--dev"] if defined?(JRUBY_VERSION)
diff --git a/activejob/activejob.gemspec b/activejob/activejob.gemspec
index e97bb40abf..71e32f695b 100644
--- a/activejob/activejob.gemspec
+++ b/activejob/activejob.gemspec
@@ -1,23 +1,30 @@
-version = File.read(File.expand_path('../../RAILS_VERSION', __FILE__)).strip
+# frozen_string_literal: true
+
+version = File.read(File.expand_path("../RAILS_VERSION", __dir__)).strip
 
 Gem::Specification.new do |s|
   s.platform    = Gem::Platform::RUBY
-  s.name        = 'activejob'
+  s.name        = "activejob"
   s.version     = version
-  s.summary     = 'Job framework with pluggable queues.'
-  s.description = 'Declare job classes that can be run by a variety of queueing backends.'
+  s.summary     = "Job framework with pluggable queues."
+  s.description = "Declare job classes that can be run by a variety of queueing backends."
+
+  s.required_ruby_version = ">= 2.2.2"
 
-  s.required_ruby_version = '>= 2.2.2'
+  s.license = "MIT"
 
-  s.license = 'MIT'
+  s.author   = "David Heinemeier Hansson"
+  s.email    = "david@loudthinking.com"
+  s.homepage = "http://rubyonrails.org"
 
-  s.author   = 'David Heinemeier Hansson'
-  s.email    = 'david@loudthinking.com'
-  s.homepage = 'http://rubyonrails.org'
+  s.files        = Dir["CHANGELOG.md", "MIT-LICENSE", "README.md", "lib/**/*"]
+  s.require_path = "lib"
 
-  s.files        = Dir['CHANGELOG.md', 'MIT-LICENSE', 'README.md', 'lib/**/*']
-  s.require_path = 'lib'
+  s.metadata = {
+    "source_code_uri" => "https://github.com/rails/rails/tree/v#{version}/activejob",
+    "changelog_uri"   => "https://github.com/rails/rails/blob/v#{version}/activejob/CHANGELOG.md"
+  }
 
-  s.add_dependency 'activesupport', version
-  s.add_dependency 'globalid', '>= 0.3.6'
+  s.add_dependency "activesupport", version
+  s.add_dependency "globalid", ">= 0.3.6"
 end
diff --git a/activejob/bin/test b/activejob/bin/test
new file mode 100755
index 0000000000..c53377cc97
--- /dev/null
+++ b/activejob/bin/test
@@ -0,0 +1,5 @@
+#!/usr/bin/env ruby
+# frozen_string_literal: true
+
+COMPONENT_ROOT = File.expand_path("..", __dir__)
+require_relative "../../tools/test"
diff --git a/activejob/lib/active_job.rb b/activejob/lib/active_job.rb
index 4b9065cf50..626abaa767 100644
--- a/activejob/lib/active_job.rb
+++ b/activejob/lib/active_job.rb
@@ -1,5 +1,7 @@
+# frozen_string_literal: true
+
 #--
-# Copyright (c) 2014-2016 David Heinemeier Hansson
+# Copyright (c) 2014-2018 David Heinemeier Hansson
 #
 # Permission is hereby granted, free of charge, to any person obtaining
 # a copy of this software and associated documentation files (the
@@ -21,10 +23,10 @@
 # WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 #++
 
-require 'active_support'
-require 'active_support/rails'
-require 'active_job/version'
-require 'global_id'
+require "active_support"
+require "active_support/rails"
+require "active_job/version"
+require "global_id"
 
 module ActiveJob
   extend ActiveSupport::Autoload
diff --git a/activejob/lib/active_job/arguments.rb b/activejob/lib/active_job/arguments.rb
index a5c749e5e7..de11e7fcb1 100644
--- a/activejob/lib/active_job/arguments.rb
+++ b/activejob/lib/active_job/arguments.rb
@@ -1,26 +1,16 @@
-require 'active_support/core_ext/hash'
+# frozen_string_literal: true
+
+require "active_support/core_ext/hash"
 
 module ActiveJob
   # Raised when an exception is raised during job arguments deserialization.
   #
   # Wraps the original exception raised as +cause+.
   class DeserializationError < StandardError
-    def initialize(e = nil) #:nodoc:
-      if e
-        ActiveSupport::Deprecation.warn("Passing #original_exception is deprecated and has no effect. " \
-                                        "Exceptions will automatically capture the original exception.", caller)
-      end
-
+    def initialize #:nodoc:
       super("Error while trying to deserialize arguments: #{$!.message}")
       set_backtrace $!.backtrace
     end
-
-    # The original exception that was raised during deserialization of job
-    # arguments.
-    def original_exception
-      ActiveSupport::Deprecation.warn("#original_exception is deprecated. Use #cause instead.", caller)
-      cause
-    end
   end
 
   # Raised when an unsupported argument type is set as a job argument. We
@@ -34,8 +24,8 @@ module ActiveJob
   module Arguments
     extend self
     # :nodoc:
-    # Calls #uniq since Integer, Fixnum, and Bignum are all the same class on Ruby 2.4+
-    TYPE_WHITELIST = [ NilClass, String, Integer, Fixnum, Bignum, Float, BigDecimal, TrueClass, FalseClass ].uniq
+    TYPE_WHITELIST = [ NilClass, String, Integer, Float, BigDecimal, TrueClass, FalseClass ]
+    TYPE_WHITELIST.push(Fixnum, Bignum) unless 1.class == Integer
 
     # Serializes a set of arguments. Whitelisted types are returned
     # as-is. Arrays/Hashes are serialized element by element.
@@ -55,11 +45,11 @@ module ActiveJob
 
     private
       # :nodoc:
-      GLOBALID_KEY = '_aj_globalid'.freeze
+      GLOBALID_KEY = "_aj_globalid".freeze
       # :nodoc:
-      SYMBOL_KEYS_KEY = '_aj_symbol_keys'.freeze
+      SYMBOL_KEYS_KEY = "_aj_symbol_keys".freeze
       # :nodoc:
-      WITH_INDIFFERENT_ACCESS_KEY = '_aj_hash_with_indifferent_access'.freeze
+      WITH_INDIFFERENT_ACCESS_KEY = "_aj_hash_with_indifferent_access".freeze
       private_constant :GLOBALID_KEY, :SYMBOL_KEYS_KEY, :WITH_INDIFFERENT_ACCESS_KEY
 
       def serialize_argument(argument)
@@ -104,7 +94,7 @@ module ActiveJob
       end
 
       def serialized_global_id?(hash)
-        hash.size == 1 and hash.include?(GLOBALID_KEY)
+        hash.size == 1 && hash.include?(GLOBALID_KEY)
       end
 
       def deserialize_global_id(hash)
diff --git a/activejob/lib/active_job/base.rb b/activejob/lib/active_job/base.rb
index ff5c69ddc6..ae112abb2c 100644
--- a/activejob/lib/active_job/base.rb
+++ b/activejob/lib/active_job/base.rb
@@ -1,12 +1,15 @@
-require 'active_job/core'
-require 'active_job/queue_adapter'
-require 'active_job/queue_name'
-require 'active_job/queue_priority'
-require 'active_job/enqueuing'
-require 'active_job/execution'
-require 'active_job/callbacks'
-require 'active_job/logging'
-require 'active_job/translation'
+# frozen_string_literal: true
+
+require "active_job/core"
+require "active_job/queue_adapter"
+require "active_job/queue_name"
+require "active_job/queue_priority"
+require "active_job/enqueuing"
+require "active_job/execution"
+require "active_job/callbacks"
+require "active_job/exceptions"
+require "active_job/logging"
+require "active_job/translation"
 
 module ActiveJob #:nodoc:
   # = Active Job
@@ -62,6 +65,7 @@ module ActiveJob #:nodoc:
     include Enqueuing
     include Execution
     include Callbacks
+    include Exceptions
     include Logging
     include Translation
 
diff --git a/activejob/lib/active_job/callbacks.rb b/activejob/lib/active_job/callbacks.rb
index b206522a60..334b24fb3b 100644
--- a/activejob/lib/active_job/callbacks.rb
+++ b/activejob/lib/active_job/callbacks.rb
@@ -1,10 +1,12 @@
-require 'active_support/callbacks'
+# frozen_string_literal: true
+
+require "active_support/callbacks"
 
 module ActiveJob
   # = Active Job Callbacks
   #
   # Active Job provides hooks during the life cycle of a job. Callbacks allow you
-  # to trigger logic during the life cycle of a job. Available callbacks are:
+  # to trigger logic during this cycle. Available callbacks are:
   #
   # * <tt>before_enqueue</tt>
   # * <tt>around_enqueue</tt>
@@ -13,6 +15,8 @@ module ActiveJob
   # * <tt>around_perform</tt>
   # * <tt>after_perform</tt>
   #
+  # NOTE: Calling the same callback multiple times will overwrite previous callback definitions.
+  #
   module Callbacks
     extend  ActiveSupport::Concern
     include ActiveSupport::Callbacks
diff --git a/activejob/lib/active_job/configured_job.rb b/activejob/lib/active_job/configured_job.rb
index 979280b910..67daf48b36 100644
--- a/activejob/lib/active_job/configured_job.rb
+++ b/activejob/lib/active_job/configured_job.rb
@@ -1,6 +1,8 @@
+# frozen_string_literal: true
+
 module ActiveJob
   class ConfiguredJob #:nodoc:
-    def initialize(job_class, options={})
+    def initialize(job_class, options = {})
       @options = options
       @job_class = job_class
     end
diff --git a/activejob/lib/active_job/core.rb b/activejob/lib/active_job/core.rb
index f7f882c998..879746fc01 100644
--- a/activejob/lib/active_job/core.rb
+++ b/activejob/lib/active_job/core.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActiveJob
   # Provides general behavior that will be included into every Active Job
   # object that inherits from ActiveJob::Base.
@@ -24,6 +26,9 @@ module ActiveJob
       # ID optionally provided by adapter
       attr_accessor :provider_job_id
 
+      # Number of times this job has been executed (which increments on every retry, like after an exception).
+      attr_accessor :executions
+
       # I18n.locale to be used during the job.
       attr_accessor :locale
     end
@@ -33,7 +38,7 @@ module ActiveJob
     module ClassMethods
       # Creates a new job instance from a hash created with +serialize+
       def deserialize(job_data)
-        job = job_data['job_class'].constantize.new
+        job = job_data["job_class"].constantize.new
         job.deserialize(job_data)
         job
       end
@@ -56,7 +61,7 @@ module ActiveJob
       #    VideoJob.set(queue: :some_queue, wait: 5.minutes).perform_later(Video.last)
       #    VideoJob.set(queue: :some_queue, wait_until: Time.now.tomorrow).perform_later(Video.last)
       #    VideoJob.set(queue: :some_queue, wait: 5.minutes, priority: 10).perform_later(Video.last)
-      def set(options={})
+      def set(options = {})
         ConfiguredJob.new(self, options)
       end
     end
@@ -68,18 +73,21 @@ module ActiveJob
       @job_id     = SecureRandom.uuid
       @queue_name = self.class.queue_name
       @priority   = self.class.priority
+      @executions = 0
     end
 
     # Returns a hash with the job data that can safely be passed to the
     # queueing adapter.
     def serialize
       {
-        'job_class'  => self.class.name,
-        'job_id'     => job_id,
-        'queue_name' => queue_name,
-        'priority'   => priority,
-        'arguments'  => serialize_arguments(arguments),
-        'locale'     => I18n.locale.to_s
+        "job_class"  => self.class.name,
+        "job_id"     => job_id,
+        "provider_job_id" => provider_job_id,
+        "queue_name" => queue_name,
+        "priority"   => priority,
+        "arguments"  => serialize_arguments(arguments),
+        "executions" => executions,
+        "locale"     => I18n.locale.to_s
       }
     end
 
@@ -89,26 +97,34 @@ module ActiveJob
     # ==== Examples
     #
     #    class DeliverWebhookJob < ActiveJob::Base
+    #      attr_writer :attempt_number
+    #
+    #      def attempt_number
+    #        @attempt_number ||= 0
+    #      end
+    #
     #      def serialize
-    #        super.merge('attempt_number' => (@attempt_number || 0) + 1)
+    #        super.merge('attempt_number' => attempt_number + 1)
     #      end
     #
     #      def deserialize(job_data)
     #        super
-    #        @attempt_number = job_data['attempt_number']
+    #        self.attempt_number = job_data['attempt_number']
     #      end
     #
-    #      rescue_from(TimeoutError) do |exception|
-    #        raise exception if @attempt_number > 5
+    #      rescue_from(Timeout::Error) do |exception|
+    #        raise exception if attempt_number > 5
     #        retry_job(wait: 10)
     #      end
     #    end
     def deserialize(job_data)
-      self.job_id               = job_data['job_id']
-      self.queue_name           = job_data['queue_name']
-      self.priority             = job_data['priority']
-      self.serialized_arguments = job_data['arguments']
-      self.locale               = job_data['locale'] || I18n.locale.to_s
+      self.job_id               = job_data["job_id"]
+      self.provider_job_id      = job_data["provider_job_id"]
+      self.queue_name           = job_data["queue_name"]
+      self.priority             = job_data["priority"]
+      self.serialized_arguments = job_data["arguments"]
+      self.executions           = job_data["executions"]
+      self.locale               = job_data["locale"] || I18n.locale.to_s
     end
 
     private
diff --git a/activejob/lib/active_job/enqueuing.rb b/activejob/lib/active_job/enqueuing.rb
index 9dc3c0fa57..53cb98fc71 100644
--- a/activejob/lib/active_job/enqueuing.rb
+++ b/activejob/lib/active_job/enqueuing.rb
@@ -1,14 +1,16 @@
-require 'active_job/arguments'
+# frozen_string_literal: true
+
+require "active_job/arguments"
 
 module ActiveJob
-  # Provides behavior for enqueuing and retrying jobs.
+  # Provides behavior for enqueuing jobs.
   module Enqueuing
     extend ActiveSupport::Concern
 
     # Includes the +perform_later+ method for job initialization.
     module ClassMethods
       # Push a job onto the queue. The arguments must be legal JSON types
-      # (string, int, float, nil, true, false, hash or array) or
+      # (+string+, +int+, +float+, +nil+, +true+, +false+, +hash+ or +array+) or
       # GlobalID::Identification instances. Arbitrary Ruby objects
       # are not supported.
       #
@@ -18,37 +20,12 @@ module ActiveJob
         job_or_instantiate(*args).enqueue
       end
 
-      protected
-        def job_or_instantiate(*args)
+      private
+        def job_or_instantiate(*args) # :doc:
           args.first.is_a?(self) ? args.first : new(*args)
         end
     end
 
-    # Reschedules the job to be re-executed. This is useful in combination
-    # with the +rescue_from+ option. When you rescue an exception from your job
-    # you can ask Active Job to retry performing your job.
-    #
-    # ==== Options
-    # * <tt>:wait</tt> - Enqueues the job with the specified delay
-    # * <tt>:wait_until</tt> - Enqueues the job at the time specified
-    # * <tt>:queue</tt> - Enqueues the job on the specified queue
-    # * <tt>:priority</tt> - Enqueues the job with the specified priority
-    #
-    # ==== Examples
-    #
-    #  class SiteScraperJob < ActiveJob::Base
-    #    rescue_from(ErrorLoadingSite) do
-    #      retry_job queue: :low_priority
-    #    end
-    #
-    #    def perform(*args)
-    #      # raise ErrorLoadingSite if cannot scrape
-    #    end
-    #  end
-    def retry_job(options={})
-      enqueue options
-    end
-
     # Enqueues the job to be performed by the queue adapter.
     #
     # ==== Options
@@ -64,14 +41,14 @@ module ActiveJob
     #    my_job_instance.enqueue queue: :important
     #    my_job_instance.enqueue wait_until: Date.tomorrow.midnight
     #    my_job_instance.enqueue priority: 10
-    def enqueue(options={})
+    def enqueue(options = {})
       self.scheduled_at = options[:wait].seconds.from_now.to_f if options[:wait]
       self.scheduled_at = options[:wait_until].to_f if options[:wait_until]
       self.queue_name   = self.class.queue_name_from_part(options[:queue]) if options[:queue]
       self.priority     = options[:priority].to_i if options[:priority]
       run_callbacks :enqueue do
-        if self.scheduled_at
-          self.class.queue_adapter.enqueue_at self, self.scheduled_at
+        if scheduled_at
+          self.class.queue_adapter.enqueue_at self, scheduled_at
         else
           self.class.queue_adapter.enqueue self
         end
diff --git a/activejob/lib/active_job/exceptions.rb b/activejob/lib/active_job/exceptions.rb
new file mode 100644
index 0000000000..8b4a88ba6a
--- /dev/null
+++ b/activejob/lib/active_job/exceptions.rb
@@ -0,0 +1,124 @@
+# frozen_string_literal: true
+
+require "active_support/core_ext/numeric/time"
+
+module ActiveJob
+  # Provides behavior for retrying and discarding jobs on exceptions.
+  module Exceptions
+    extend ActiveSupport::Concern
+
+    module ClassMethods
+      # Catch the exception and reschedule job for re-execution after so many seconds, for a specific number of attempts.
+      # If the exception keeps getting raised beyond the specified number of attempts, the exception is allowed to
+      # bubble up to the underlying queuing system, which may have its own retry mechanism or place it in a
+      # holding queue for inspection.
+      #
+      # You can also pass a block that'll be invoked if the retry attempts fail for custom logic rather than letting
+      # the exception bubble up. This block is yielded with the job instance as the first and the error instance as the second parameter.
+      #
+      # ==== Options
+      # * <tt>:wait</tt> - Re-enqueues the job with a delay specified either in seconds (default: 3 seconds),
+      #   as a computing proc that the number of executions so far as an argument, or as a symbol reference of
+      #   <tt>:exponentially_longer</tt>, which applies the wait algorithm of <tt>(executions ** 4) + 2</tt>
+      #   (first wait 3s, then 18s, then 83s, etc)
+      # * <tt>:attempts</tt> - Re-enqueues the job the specified number of times (default: 5 attempts)
+      # * <tt>:queue</tt> - Re-enqueues the job on a different queue
+      # * <tt>:priority</tt> - Re-enqueues the job with a different priority
+      #
+      # ==== Examples
+      #
+      #  class RemoteServiceJob < ActiveJob::Base
+      #    retry_on CustomAppException # defaults to 3s wait, 5 attempts
+      #    retry_on AnotherCustomAppException, wait: ->(executions) { executions * 2 }
+      #    retry_on(YetAnotherCustomAppException) do |job, exception|
+      #      ExceptionNotifier.caught(exception)
+      #    end
+      #    retry_on ActiveRecord::Deadlocked, wait: 5.seconds, attempts: 3
+      #    retry_on Net::OpenTimeout, wait: :exponentially_longer, attempts: 10
+      #
+      #    def perform(*args)
+      #      # Might raise CustomAppException, AnotherCustomAppException, or YetAnotherCustomAppException for something domain specific
+      #      # Might raise ActiveRecord::Deadlocked when a local db deadlock is detected
+      #      # Might raise Net::OpenTimeout when the remote service is down
+      #    end
+      #  end
+      def retry_on(exception, wait: 3.seconds, attempts: 5, queue: nil, priority: nil)
+        rescue_from exception do |error|
+          if executions < attempts
+            logger.error "Retrying #{self.class} in #{wait} seconds, due to a #{exception}. The original exception was #{error.cause.inspect}."
+            retry_job wait: determine_delay(wait), queue: queue, priority: priority
+          else
+            if block_given?
+              yield self, error
+            else
+              logger.error "Stopped retrying #{self.class} due to a #{exception}, which reoccurred on #{executions} attempts. The original exception was #{error.cause.inspect}."
+              raise error
+            end
+          end
+        end
+      end
+
+      # Discard the job with no attempts to retry, if the exception is raised. This is useful when the subject of the job,
+      # like an Active Record, is no longer available, and the job is thus no longer relevant.
+      #
+      # ==== Example
+      #
+      #  class SearchIndexingJob < ActiveJob::Base
+      #    discard_on ActiveJob::DeserializationError
+      #
+      #    def perform(record)
+      #      # Will raise ActiveJob::DeserializationError if the record can't be deserialized
+      #    end
+      #  end
+      def discard_on(exception)
+        rescue_from exception do |error|
+          logger.error "Discarded #{self.class} due to a #{exception}. The original exception was #{error.cause.inspect}."
+        end
+      end
+    end
+
+    # Reschedules the job to be re-executed. This is useful in combination
+    # with the +rescue_from+ option. When you rescue an exception from your job
+    # you can ask Active Job to retry performing your job.
+    #
+    # ==== Options
+    # * <tt>:wait</tt> - Enqueues the job with the specified delay in seconds
+    # * <tt>:wait_until</tt> - Enqueues the job at the time specified
+    # * <tt>:queue</tt> - Enqueues the job on the specified queue
+    # * <tt>:priority</tt> - Enqueues the job with the specified priority
+    #
+    # ==== Examples
+    #
+    #  class SiteScraperJob < ActiveJob::Base
+    #    rescue_from(ErrorLoadingSite) do
+    #      retry_job queue: :low_priority
+    #    end
+    #
+    #    def perform(*args)
+    #      # raise ErrorLoadingSite if cannot scrape
+    #    end
+    #  end
+    def retry_job(options = {})
+      enqueue options
+    end
+
+    private
+      def determine_delay(seconds_or_duration_or_algorithm)
+        case seconds_or_duration_or_algorithm
+        when :exponentially_longer
+          (executions**4) + 2
+        when ActiveSupport::Duration
+          duration = seconds_or_duration_or_algorithm
+          duration.to_i
+        when Integer
+          seconds = seconds_or_duration_or_algorithm
+          seconds
+        when Proc
+          algorithm = seconds_or_duration_or_algorithm
+          algorithm.call(executions)
+        else
+          raise "Couldn't determine a delay based on #{seconds_or_duration_or_algorithm.inspect}"
+        end
+      end
+  end
+end
diff --git a/activejob/lib/active_job/execution.rb b/activejob/lib/active_job/execution.rb
index 4e4acfc2c2..d75be376ec 100644
--- a/activejob/lib/active_job/execution.rb
+++ b/activejob/lib/active_job/execution.rb
@@ -1,5 +1,7 @@
-require 'active_support/rescuable'
-require 'active_job/arguments'
+# frozen_string_literal: true
+
+require "active_support/rescuable"
+require "active_job/arguments"
 
 module ActiveJob
   module Execution
@@ -31,6 +33,9 @@ module ActiveJob
     def perform_now
       deserialize_arguments_if_needed
       run_callbacks :perform do
+        # Guard against jobs that were persisted before we started counting executions by zeroing out nil counters
+        self.executions = (executions || 0) + 1
+
         perform(*arguments)
       end
     rescue => exception
diff --git a/activejob/lib/active_job/gem_version.rb b/activejob/lib/active_job/gem_version.rb
index 0d50c27938..49dfd4095e 100644
--- a/activejob/lib/active_job/gem_version.rb
+++ b/activejob/lib/active_job/gem_version.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActiveJob
   # Returns the version of the currently loaded Active Job as a <tt>Gem::Version</tt>
   def self.gem_version
@@ -6,9 +8,9 @@ module ActiveJob
 
   module VERSION
     MAJOR = 5
-    MINOR = 1
+    MINOR = 2
     TINY  = 0
-    PRE   = "alpha"
+    PRE   = "beta2"
 
     STRING = [MAJOR, MINOR, TINY, PRE].compact.join(".")
   end
diff --git a/activejob/lib/active_job/logging.rb b/activejob/lib/active_job/logging.rb
index d5c7920131..f53b7eaee5 100644
--- a/activejob/lib/active_job/logging.rb
+++ b/activejob/lib/active_job/logging.rb
@@ -1,14 +1,16 @@
-require 'active_support/core_ext/hash/transform_values'
-require 'active_support/core_ext/string/filters'
-require 'active_support/tagged_logging'
-require 'active_support/logger'
+# frozen_string_literal: true
+
+require "active_support/core_ext/hash/transform_values"
+require "active_support/core_ext/string/filters"
+require "active_support/tagged_logging"
+require "active_support/logger"
 
 module ActiveJob
   module Logging #:nodoc:
     extend ActiveSupport::Concern
 
     included do
-      cattr_accessor(:logger) { ActiveSupport::TaggedLogging.new(ActiveSupport::Logger.new(STDOUT)) }
+      cattr_accessor :logger, default: ActiveSupport::TaggedLogging.new(ActiveSupport::Logger.new(STDOUT))
 
       around_enqueue do |_, block, _|
         tag_logger do
@@ -18,7 +20,7 @@ module ActiveJob
 
       around_perform do |job, block, _|
         tag_logger(job.class.name, job.job_id) do
-          payload = {adapter: job.class.queue_adapter, job: job}
+          payload = { adapter: job.class.queue_adapter, job: job }
           ActiveSupport::Notifications.instrument("perform_start.active_job", payload.dup)
           ActiveSupport::Notifications.instrument("perform.active_job", payload) do
             block.call
@@ -41,7 +43,7 @@ module ActiveJob
       def tag_logger(*tags)
         if logger.respond_to?(:tagged)
           tags.unshift "ActiveJob" unless logger_tagged_by_active_job?
-          logger.tagged(*tags){ yield }
+          logger.tagged(*tags) { yield }
         else
           yield
         end
@@ -51,70 +53,77 @@ module ActiveJob
         logger.formatter.current_tags.include?("ActiveJob")
       end
 
-    class LogSubscriber < ActiveSupport::LogSubscriber #:nodoc:
-      def enqueue(event)
-        info do
-          job = event.payload[:job]
-          "Enqueued #{job.class.name} (Job ID: #{job.job_id}) to #{queue_name(event)}" + args_info(job)
+      class LogSubscriber < ActiveSupport::LogSubscriber #:nodoc:
+        def enqueue(event)
+          info do
+            job = event.payload[:job]
+            "Enqueued #{job.class.name} (Job ID: #{job.job_id}) to #{queue_name(event)}" + args_info(job)
+          end
         end
-      end
 
-      def enqueue_at(event)
-        info do
-          job = event.payload[:job]
-          "Enqueued #{job.class.name} (Job ID: #{job.job_id}) to #{queue_name(event)} at #{scheduled_at(event)}" + args_info(job)
+        def enqueue_at(event)
+          info do
+            job = event.payload[:job]
+            "Enqueued #{job.class.name} (Job ID: #{job.job_id}) to #{queue_name(event)} at #{scheduled_at(event)}" + args_info(job)
+          end
         end
-      end
 
-      def perform_start(event)
-        info do
-          job = event.payload[:job]
-          "Performing #{job.class.name} from #{queue_name(event)}" + args_info(job)
+        def perform_start(event)
+          info do
+            job = event.payload[:job]
+            "Performing #{job.class.name} (Job ID: #{job.job_id}) from #{queue_name(event)}" + args_info(job)
+          end
         end
-      end
 
-      def perform(event)
-        info do
+        def perform(event)
           job = event.payload[:job]
-          "Performed #{job.class.name} from #{queue_name(event)} in #{event.duration.round(2)}ms"
+          ex = event.payload[:exception_object]
+          if ex
+            error do
+              "Error performing #{job.class.name} (Job ID: #{job.job_id}) from #{queue_name(event)} in #{event.duration.round(2)}ms: #{ex.class} (#{ex.message}):\n" + Array(ex.backtrace).join("\n")
+            end
+          else
+            info do
+              "Performed #{job.class.name} (Job ID: #{job.job_id}) from #{queue_name(event)} in #{event.duration.round(2)}ms"
+            end
+          end
         end
-      end
 
-      private
-        def queue_name(event)
-          event.payload[:adapter].class.name.demodulize.remove('Adapter') + "(#{event.payload[:job].queue_name})"
-        end
+        private
+          def queue_name(event)
+            event.payload[:adapter].class.name.demodulize.remove("Adapter") + "(#{event.payload[:job].queue_name})"
+          end
 
-        def args_info(job)
-          if job.arguments.any?
-            ' with arguments: ' +
-              job.arguments.map { |arg| format(arg).inspect }.join(', ')
-          else
-            ''
+          def args_info(job)
+            if job.arguments.any?
+              " with arguments: " +
+                job.arguments.map { |arg| format(arg).inspect }.join(", ")
+            else
+              ""
+            end
           end
-        end
 
-        def format(arg)
-          case arg
-          when Hash
-            arg.transform_values { |value| format(value) }
-          when Array
-            arg.map { |value| format(value) }
-          when GlobalID::Identification
-            arg.to_global_id rescue arg
-          else
-            arg
+          def format(arg)
+            case arg
+            when Hash
+              arg.transform_values { |value| format(value) }
+            when Array
+              arg.map { |value| format(value) }
+            when GlobalID::Identification
+              arg.to_global_id rescue arg
+            else
+              arg
+            end
           end
-        end
 
-        def scheduled_at(event)
-          Time.at(event.payload[:job].scheduled_at).utc
-        end
+          def scheduled_at(event)
+            Time.at(event.payload[:job].scheduled_at).utc
+          end
 
-        def logger
-          ActiveJob::Base.logger
-        end
-    end
+          def logger
+            ActiveJob::Base.logger
+          end
+      end
   end
 end
 
diff --git a/activejob/lib/active_job/queue_adapter.rb b/activejob/lib/active_job/queue_adapter.rb
index 72e4ebf935..dd05800baf 100644
--- a/activejob/lib/active_job/queue_adapter.rb
+++ b/activejob/lib/active_job/queue_adapter.rb
@@ -1,6 +1,6 @@
-require 'active_job/queue_adapters/inline_adapter'
-require 'active_support/core_ext/class/attribute'
-require 'active_support/core_ext/string/inflections'
+# frozen_string_literal: true
+
+require "active_support/core_ext/string/inflections"
 
 module ActiveJob
   # The <tt>ActiveJob::QueueAdapter</tt> module is used to load the
@@ -9,6 +9,7 @@ module ActiveJob
     extend ActiveSupport::Concern
 
     included do
+      class_attribute :_queue_adapter_name, instance_accessor: false, instance_predicate: false
       class_attribute :_queue_adapter, instance_accessor: false, instance_predicate: false
       self.queue_adapter = :async
     end
@@ -21,43 +22,45 @@ module ActiveJob
         _queue_adapter
       end
 
+      def queue_adapter_name
+        _queue_adapter_name
+      end
+
       # Specify the backend queue provider. The default queue adapter
       # is the +:async+ queue. See QueueAdapters for more
       # information.
       def queue_adapter=(name_or_adapter_or_class)
-        self._queue_adapter = interpret_adapter(name_or_adapter_or_class)
+        interpret_adapter(name_or_adapter_or_class)
       end
 
       private
 
-      def interpret_adapter(name_or_adapter_or_class)
-        case name_or_adapter_or_class
-        when Symbol, String
-          ActiveJob::QueueAdapters.lookup(name_or_adapter_or_class).new
-        else
-          if queue_adapter?(name_or_adapter_or_class)
-            name_or_adapter_or_class
-          elsif queue_adapter_class?(name_or_adapter_or_class)
-            ActiveSupport::Deprecation.warn "Passing an adapter class is deprecated " \
-              "and will be removed in Rails 5.1. Please pass an adapter name " \
-              "(.queue_adapter = :#{name_or_adapter_or_class.name.demodulize.remove('Adapter').underscore}) " \
-              "or an instance (.queue_adapter = #{name_or_adapter_or_class.name}.new) instead."
-              name_or_adapter_or_class.new
+        def interpret_adapter(name_or_adapter_or_class)
+          case name_or_adapter_or_class
+          when Symbol, String
+            assign_adapter(name_or_adapter_or_class.to_s,
+                           ActiveJob::QueueAdapters.lookup(name_or_adapter_or_class).new)
           else
-            raise ArgumentError
+            if queue_adapter?(name_or_adapter_or_class)
+              adapter_name = "#{name_or_adapter_or_class.class.name.demodulize.remove('Adapter').underscore}"
+              assign_adapter(adapter_name,
+                             name_or_adapter_or_class)
+            else
+              raise ArgumentError
+            end
           end
         end
-      end
 
-      QUEUE_ADAPTER_METHODS = [:enqueue, :enqueue_at].freeze
+        def assign_adapter(adapter_name, queue_adapter)
+          self._queue_adapter_name = adapter_name
+          self._queue_adapter = queue_adapter
+        end
 
-      def queue_adapter?(object)
-        QUEUE_ADAPTER_METHODS.all? { |meth| object.respond_to?(meth) }
-      end
+        QUEUE_ADAPTER_METHODS = [:enqueue, :enqueue_at].freeze
 
-      def queue_adapter_class?(object)
-        object.is_a?(Class) && QUEUE_ADAPTER_METHODS.all? { |meth| object.public_method_defined?(meth) }
-      end
+        def queue_adapter?(object)
+          QUEUE_ADAPTER_METHODS.all? { |meth| object.respond_to?(meth) }
+        end
     end
   end
 end
diff --git a/activejob/lib/active_job/queue_adapters.rb b/activejob/lib/active_job/queue_adapters.rb
index 71154d8785..c1a1d3c510 100644
--- a/activejob/lib/active_job/queue_adapters.rb
+++ b/activejob/lib/active_job/queue_adapters.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActiveJob
   # == Active Job adapters
   #
@@ -8,7 +10,7 @@ module ActiveJob
   # * {Qu}[https://github.com/bkeepers/qu]
   # * {Que}[https://github.com/chanks/que]
   # * {queue_classic}[https://github.com/QueueClassic/queue_classic]
-  # * {Resque 1.x}[https://github.com/resque/resque/tree/1-x-stable]
+  # * {Resque}[https://github.com/resque/resque]
   # * {Sidekiq}[http://sidekiq.org]
   # * {Sneakers}[https://github.com/jondot/sneakers]
   # * {Sucker Punch}[https://github.com/brandonhilkert/sucker_punch]
@@ -121,7 +123,7 @@ module ActiveJob
     autoload :SuckerPunchAdapter
     autoload :TestAdapter
 
-    ADAPTER = 'Adapter'.freeze
+    ADAPTER = "Adapter".freeze
     private_constant :ADAPTER
 
     class << self
diff --git a/activejob/lib/active_job/queue_adapters/async_adapter.rb b/activejob/lib/active_job/queue_adapters/async_adapter.rb
index 922bc4afce..ebf6f384e3 100644
--- a/activejob/lib/active_job/queue_adapters/async_adapter.rb
+++ b/activejob/lib/active_job/queue_adapters/async_adapter.rb
@@ -1,7 +1,9 @@
-require 'securerandom'
-require 'concurrent/scheduled_task'
-require 'concurrent/executor/thread_pool_executor'
-require 'concurrent/utility/processor_counter'
+# frozen_string_literal: true
+
+require "securerandom"
+require "concurrent/scheduled_task"
+require "concurrent/executor/thread_pool_executor"
+require "concurrent/utility/processor_counter"
 
 module ActiveJob
   module QueueAdapters
@@ -29,7 +31,7 @@ module ActiveJob
     # jobs. Since jobs share a single thread pool, long-running jobs will block
     # short-lived jobs. Fine for dev/test; bad for production.
     class AsyncAdapter
-      # See {Concurrent::ThreadPoolExecutor}[http://ruby-concurrency.github.io/concurrent-ruby/Concurrent/ThreadPoolExecutor.html] for executor options.
+      # See {Concurrent::ThreadPoolExecutor}[https://ruby-concurrency.github.io/concurrent-ruby/Concurrent/ThreadPoolExecutor.html] for executor options.
       def initialize(**executor_options)
         @scheduler = Scheduler.new(**executor_options)
       end
diff --git a/activejob/lib/active_job/queue_adapters/backburner_adapter.rb b/activejob/lib/active_job/queue_adapters/backburner_adapter.rb
index 17703e3e41..0ba93c6e0b 100644
--- a/activejob/lib/active_job/queue_adapters/backburner_adapter.rb
+++ b/activejob/lib/active_job/queue_adapters/backburner_adapter.rb
@@ -1,4 +1,6 @@
-require 'backburner'
+# frozen_string_literal: true
+
+require "backburner"
 
 module ActiveJob
   module QueueAdapters
diff --git a/activejob/lib/active_job/queue_adapters/delayed_job_adapter.rb b/activejob/lib/active_job/queue_adapters/delayed_job_adapter.rb
index 0a785fad3b..8eeef32b99 100644
--- a/activejob/lib/active_job/queue_adapters/delayed_job_adapter.rb
+++ b/activejob/lib/active_job/queue_adapters/delayed_job_adapter.rb
@@ -1,4 +1,6 @@
-require 'delayed_job'
+# frozen_string_literal: true
+
+require "delayed_job"
 
 module ActiveJob
   module QueueAdapters
@@ -32,6 +34,10 @@ module ActiveJob
           @job_data = job_data
         end
 
+        def display_name
+          "#{job_data['job_class']} [#{job_data['job_id']}] from DelayedJob(#{job_data['queue_name']}) with arguments: #{job_data['arguments']}"
+        end
+
         def perform
           Base.execute(job_data)
         end
diff --git a/activejob/lib/active_job/queue_adapters/inline_adapter.rb b/activejob/lib/active_job/queue_adapters/inline_adapter.rb
index 0496f8449e..3d0b590212 100644
--- a/activejob/lib/active_job/queue_adapters/inline_adapter.rb
+++ b/activejob/lib/active_job/queue_adapters/inline_adapter.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActiveJob
   module QueueAdapters
     # == Active Job Inline adapter
diff --git a/activejob/lib/active_job/queue_adapters/qu_adapter.rb b/activejob/lib/active_job/queue_adapters/qu_adapter.rb
index 0e198922fc..bd7003e177 100644
--- a/activejob/lib/active_job/queue_adapters/qu_adapter.rb
+++ b/activejob/lib/active_job/queue_adapters/qu_adapter.rb
@@ -1,4 +1,6 @@
-require 'qu'
+# frozen_string_literal: true
+
+require "qu"
 
 module ActiveJob
   module QueueAdapters
@@ -20,7 +22,7 @@ module ActiveJob
         qu_job = Qu::Payload.new(klass: JobWrapper, args: [job.serialize]).tap do |payload|
           payload.instance_variable_set(:@queue, job.queue_name)
         end.push
-        
+
         # qu_job can be nil depending on the configured backend
         job.provider_job_id = qu_job.id unless qu_job.nil?
         qu_job
@@ -32,7 +34,7 @@ module ActiveJob
 
       class JobWrapper < Qu::Job #:nodoc:
         def initialize(job_data)
-          @job_data  = job_data
+          @job_data = job_data
         end
 
         def perform
diff --git a/activejob/lib/active_job/queue_adapters/que_adapter.rb b/activejob/lib/active_job/queue_adapters/que_adapter.rb
index ab13689747..86b5e07743 100644
--- a/activejob/lib/active_job/queue_adapters/que_adapter.rb
+++ b/activejob/lib/active_job/queue_adapters/que_adapter.rb
@@ -1,4 +1,6 @@
-require 'que'
+# frozen_string_literal: true
+
+require "que"
 
 module ActiveJob
   module QueueAdapters
diff --git a/activejob/lib/active_job/queue_adapters/queue_classic_adapter.rb b/activejob/lib/active_job/queue_adapters/queue_classic_adapter.rb
index 0ee41407d8..ccc1881091 100644
--- a/activejob/lib/active_job/queue_adapters/queue_classic_adapter.rb
+++ b/activejob/lib/active_job/queue_adapters/queue_classic_adapter.rb
@@ -1,4 +1,6 @@
-require 'queue_classic'
+# frozen_string_literal: true
+
+require "queue_classic"
 
 module ActiveJob
   module QueueAdapters
@@ -26,9 +28,9 @@ module ActiveJob
       def enqueue_at(job, timestamp) #:nodoc:
         queue = build_queue(job.queue_name)
         unless queue.respond_to?(:enqueue_at)
-          raise NotImplementedError, 'To be able to schedule jobs with queue_classic ' \
-            'the QC::Queue needs to respond to `enqueue_at(timestamp, method, *args)`. ' \
-            'You can implement this yourself or you can use the queue_classic-later gem.'
+          raise NotImplementedError, "To be able to schedule jobs with queue_classic " \
+            "the QC::Queue needs to respond to `enqueue_at(timestamp, method, *args)`. " \
+            "You can implement this yourself or you can use the queue_classic-later gem."
         end
         qc_job = queue.enqueue_at(timestamp, "#{JobWrapper.name}.perform", job.serialize)
         job.provider_job_id = qc_job["id"] if qc_job.is_a?(Hash)
diff --git a/activejob/lib/active_job/queue_adapters/resque_adapter.rb b/activejob/lib/active_job/queue_adapters/resque_adapter.rb
index 417854afd8..590b4ee98d 100644
--- a/activejob/lib/active_job/queue_adapters/resque_adapter.rb
+++ b/activejob/lib/active_job/queue_adapters/resque_adapter.rb
@@ -1,12 +1,14 @@
-require 'resque'
-require 'active_support/core_ext/enumerable'
-require 'active_support/core_ext/array/access'
+# frozen_string_literal: true
+
+require "resque"
+require "active_support/core_ext/enumerable"
+require "active_support/core_ext/array/access"
 
 begin
-  require 'resque-scheduler'
+  require "resque-scheduler"
 rescue LoadError
   begin
-    require 'resque_scheduler'
+    require "resque_scheduler"
   rescue LoadError
     false
   end
@@ -27,6 +29,7 @@ module ActiveJob
     #   Rails.application.config.active_job.queue_adapter = :resque
     class ResqueAdapter
       def enqueue(job) #:nodoc:
+        JobWrapper.instance_variable_set(:@queue, job.queue_name)
         Resque.enqueue_to job.queue_name, JobWrapper, job.serialize
       end
 
diff --git a/activejob/lib/active_job/queue_adapters/sidekiq_adapter.rb b/activejob/lib/active_job/queue_adapters/sidekiq_adapter.rb
index c321776bf5..f726e6ad93 100644
--- a/activejob/lib/active_job/queue_adapters/sidekiq_adapter.rb
+++ b/activejob/lib/active_job/queue_adapters/sidekiq_adapter.rb
@@ -1,4 +1,6 @@
-require 'sidekiq'
+# frozen_string_literal: true
+
+require "sidekiq"
 
 module ActiveJob
   module QueueAdapters
@@ -16,28 +18,28 @@ module ActiveJob
     #   Rails.application.config.active_job.queue_adapter = :sidekiq
     class SidekiqAdapter
       def enqueue(job) #:nodoc:
-        #Sidekiq::Client does not support symbols as keys
+        # Sidekiq::Client does not support symbols as keys
         job.provider_job_id = Sidekiq::Client.push \
-          'class'   => JobWrapper,
-          'wrapped' => job.class.to_s,
-          'queue'   => job.queue_name,
-          'args'    => [ job.serialize ]
+          "class"   => JobWrapper,
+          "wrapped" => job.class.to_s,
+          "queue"   => job.queue_name,
+          "args"    => [ job.serialize ]
       end
 
       def enqueue_at(job, timestamp) #:nodoc:
         job.provider_job_id = Sidekiq::Client.push \
-          'class'   => JobWrapper,
-          'wrapped' => job.class.to_s,
-          'queue'   => job.queue_name,
-          'args'    => [ job.serialize ],
-          'at'      => timestamp
+          "class"   => JobWrapper,
+          "wrapped" => job.class.to_s,
+          "queue"   => job.queue_name,
+          "args"    => [ job.serialize ],
+          "at"      => timestamp
       end
 
       class JobWrapper #:nodoc:
         include Sidekiq::Worker
 
         def perform(job_data)
-          Base.execute job_data
+          Base.execute job_data.merge("provider_job_id" => jid)
         end
       end
     end
diff --git a/activejob/lib/active_job/queue_adapters/sneakers_adapter.rb b/activejob/lib/active_job/queue_adapters/sneakers_adapter.rb
index d78bdecdcb..de98a950d0 100644
--- a/activejob/lib/active_job/queue_adapters/sneakers_adapter.rb
+++ b/activejob/lib/active_job/queue_adapters/sneakers_adapter.rb
@@ -1,5 +1,7 @@
-require 'sneakers'
-require 'monitor'
+# frozen_string_literal: true
+
+require "sneakers"
+require "monitor"
 
 module ActiveJob
   module QueueAdapters
@@ -33,7 +35,7 @@ module ActiveJob
 
       class JobWrapper #:nodoc:
         include Sneakers::Worker
-        from_queue 'default'
+        from_queue "default"
 
         def work(msg)
           job_data = ActiveSupport::JSON.decode(msg)
diff --git a/activejob/lib/active_job/queue_adapters/sucker_punch_adapter.rb b/activejob/lib/active_job/queue_adapters/sucker_punch_adapter.rb
index 163c8eb212..d09e1e9143 100644
--- a/activejob/lib/active_job/queue_adapters/sucker_punch_adapter.rb
+++ b/activejob/lib/active_job/queue_adapters/sucker_punch_adapter.rb
@@ -1,4 +1,6 @@
-require 'sucker_punch'
+# frozen_string_literal: true
+
+require "sucker_punch"
 
 module ActiveJob
   module QueueAdapters
@@ -31,7 +33,7 @@ module ActiveJob
           delay = timestamp - Time.current.to_f
           JobWrapper.perform_in delay, job.serialize
         else
-          raise NotImplementedError, 'sucker_punch 1.0 does not support `enqueued_at`. Please upgrade to version ~> 2.0.0 to enable this behavior.'
+          raise NotImplementedError, "sucker_punch 1.0 does not support `enqueued_at`. Please upgrade to version ~> 2.0.0 to enable this behavior."
         end
       end
 
diff --git a/activejob/lib/active_job/queue_adapters/test_adapter.rb b/activejob/lib/active_job/queue_adapters/test_adapter.rb
index 9b7b7139f4..885f9ff01c 100644
--- a/activejob/lib/active_job/queue_adapters/test_adapter.rb
+++ b/activejob/lib/active_job/queue_adapters/test_adapter.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActiveJob
   module QueueAdapters
     # == Test adapter for Active Job
@@ -10,7 +12,7 @@ module ActiveJob
     #
     #   Rails.application.config.active_job.queue_adapter = :test
     class TestAdapter
-      attr_accessor(:perform_enqueued_jobs, :perform_enqueued_at_jobs, :filter)
+      attr_accessor(:perform_enqueued_jobs, :perform_enqueued_at_jobs, :filter, :reject)
       attr_writer(:enqueued_jobs, :performed_jobs)
 
       # Provides a store of all the enqueued jobs with the TestAdapter so you can check them.
@@ -38,23 +40,28 @@ module ActiveJob
       end
 
       private
+        def job_to_hash(job, extras = {})
+          { job: job.class, args: job.serialize.fetch("arguments"), queue: job.queue_name }.merge!(extras)
+        end
 
-      def job_to_hash(job, extras = {})
-        { job: job.class, args: job.serialize.fetch('arguments'), queue: job.queue_name }.merge!(extras)
-      end
-
-      def enqueue_or_perform(perform, job, job_data)
-        if perform
-          performed_jobs << job_data
-          Base.execute job.serialize
-        else
-          enqueued_jobs << job_data
+        def enqueue_or_perform(perform, job, job_data)
+          if perform
+            performed_jobs << job_data
+            Base.execute job.serialize
+          else
+            enqueued_jobs << job_data
+          end
         end
-      end
 
-      def filtered?(job)
-        filter && !Array(filter).include?(job.class)
-      end
+        def filtered?(job)
+          if filter
+            !Array(filter).include?(job.class)
+          elsif reject
+            Array(reject).include?(job.class)
+          else
+            false
+          end
+        end
     end
   end
 end
diff --git a/activejob/lib/active_job/queue_name.rb b/activejob/lib/active_job/queue_name.rb
index 65786a49ff..9dc6bc7f2e 100644
--- a/activejob/lib/active_job/queue_name.rb
+++ b/activejob/lib/active_job/queue_name.rb
@@ -1,11 +1,13 @@
+# frozen_string_literal: true
+
 module ActiveJob
   module QueueName
     extend ActiveSupport::Concern
 
     # Includes the ability to override the default queue name and prefix.
     module ClassMethods
-      mattr_accessor(:queue_name_prefix)
-      mattr_accessor(:default_queue_name) { "default" }
+      mattr_accessor :queue_name_prefix
+      mattr_accessor :default_queue_name, default: "default"
 
       # Specifies the name of the queue to process the job on.
       #
@@ -16,7 +18,7 @@ module ActiveJob
       #       post.to_feed!
       #     end
       #   end
-      def queue_as(part_name=nil, &block)
+      def queue_as(part_name = nil, &block)
         if block_given?
           self.queue_name = block
         else
@@ -32,11 +34,8 @@ module ActiveJob
     end
 
     included do
-      class_attribute :queue_name, instance_accessor: false
-      class_attribute :queue_name_delimiter, instance_accessor: false
-
-      self.queue_name = default_queue_name
-      self.queue_name_delimiter = '_' # set default delimiter to '_'
+      class_attribute :queue_name, instance_accessor: false, default: default_queue_name
+      class_attribute :queue_name_delimiter, instance_accessor: false, default: "_"
     end
 
     # Returns the name of the queue the job will be run on.
@@ -46,6 +45,5 @@ module ActiveJob
       end
       @queue_name
     end
-
   end
 end
diff --git a/activejob/lib/active_job/queue_priority.rb b/activejob/lib/active_job/queue_priority.rb
index 01d84910ff..063bccdb01 100644
--- a/activejob/lib/active_job/queue_priority.rb
+++ b/activejob/lib/active_job/queue_priority.rb
@@ -1,10 +1,12 @@
+# frozen_string_literal: true
+
 module ActiveJob
   module QueuePriority
     extend ActiveSupport::Concern
 
     # Includes the ability to override the default queue priority.
     module ClassMethods
-      mattr_accessor(:default_priority)
+      mattr_accessor :default_priority
 
       # Specifies the priority of the queue to create the job with.
       #
@@ -17,7 +19,7 @@ module ActiveJob
       #   end
       #
       # Specify either an argument or a block.
-      def queue_with_priority(priority=nil, &block)
+      def queue_with_priority(priority = nil, &block)
         if block_given?
           self.priority = block
         else
@@ -27,9 +29,7 @@ module ActiveJob
     end
 
     included do
-      class_attribute :priority, instance_accessor: false
-
-      self.priority = default_priority
+      class_attribute :priority, instance_accessor: false, default: default_priority
     end
 
     # Returns the priority that the job will be created with
@@ -39,6 +39,5 @@ module ActiveJob
       end
       @priority
     end
-
   end
 end
diff --git a/activejob/lib/active_job/railtie.rb b/activejob/lib/active_job/railtie.rb
index a47caa4a7e..7b0742a6d2 100644
--- a/activejob/lib/active_job/railtie.rb
+++ b/activejob/lib/active_job/railtie.rb
@@ -1,12 +1,14 @@
-require 'global_id/railtie'
-require 'active_job'
+# frozen_string_literal: true
+
+require "global_id/railtie"
+require "active_job"
 
 module ActiveJob
   # = Active Job Railtie
   class Railtie < Rails::Railtie # :nodoc:
     config.active_job = ActiveSupport::OrderedOptions.new
 
-    initializer 'active_job.logger' do
+    initializer "active_job.logger" do
       ActiveSupport.on_load(:active_job) { self.logger = ::Rails.logger }
     end
 
@@ -15,7 +17,7 @@ module ActiveJob
       options.queue_adapter ||= :async
 
       ActiveSupport.on_load(:active_job) do
-        options.each { |k,v| send("#{k}=", v) }
+        options.each { |k, v| send("#{k}=", v) }
       end
     end
 
diff --git a/activejob/lib/active_job/test_case.rb b/activejob/lib/active_job/test_case.rb
index d894a7b5cd..49cd51bdd0 100644
--- a/activejob/lib/active_job/test_case.rb
+++ b/activejob/lib/active_job/test_case.rb
@@ -1,7 +1,11 @@
-require 'active_support/test_case'
+# frozen_string_literal: true
+
+require "active_support/test_case"
 
 module ActiveJob
   class TestCase < ActiveSupport::TestCase
     include ActiveJob::TestHelper
+
+    ActiveSupport.run_load_hooks(:active_job_test_case, self)
   end
 end
diff --git a/activejob/lib/active_job/test_helper.rb b/activejob/lib/active_job/test_helper.rb
index e16af1947f..1cd2c40c15 100644
--- a/activejob/lib/active_job/test_helper.rb
+++ b/activejob/lib/active_job/test_helper.rb
@@ -1,5 +1,7 @@
-require 'active_support/core_ext/class/subclasses'
-require 'active_support/core_ext/hash/keys'
+# frozen_string_literal: true
+
+require "active_support/core_ext/class/subclasses"
+require "active_support/core_ext/hash/keys"
 
 module ActiveJob
   # Provides helper methods for testing Active Job
@@ -8,16 +10,35 @@ module ActiveJob
       :performed_jobs, :performed_jobs=,
       to: :queue_adapter
 
+    module TestQueueAdapter
+      extend ActiveSupport::Concern
+
+      included do
+        class_attribute :_test_adapter, instance_accessor: false, instance_predicate: false
+      end
+
+      module ClassMethods
+        def queue_adapter
+          self._test_adapter.nil? ? super : self._test_adapter
+        end
+
+        def disable_test_adapter
+          self._test_adapter = nil
+        end
+
+        def enable_test_adapter(test_adapter)
+          self._test_adapter = test_adapter
+        end
+      end
+    end
+
+    ActiveJob::Base.include(TestQueueAdapter)
+
     def before_setup # :nodoc:
       test_adapter = queue_adapter_for_test
 
-      @old_queue_adapters = (ActiveJob::Base.subclasses << ActiveJob::Base).select do |klass|
-        # only override explicitly set adapters, a quirk of `class_attribute`
-        klass.singleton_class.public_instance_methods(false).include?(:_queue_adapter)
-      end.map do |klass|
-        [klass, klass.queue_adapter].tap do
-          klass.queue_adapter = test_adapter
-        end
+      queue_adapter_changed_jobs.each do |klass|
+        klass.enable_test_adapter(test_adapter)
       end
 
       clear_enqueued_jobs
@@ -27,9 +48,8 @@ module ActiveJob
 
     def after_teardown # :nodoc:
       super
-      @old_queue_adapters.each do |(klass, adapter)|
-        klass.queue_adapter = adapter
-      end
+
+      queue_adapter_changed_jobs.each { |klass| klass.disable_test_adapter }
     end
 
     # Specifies the queue adapter to use with all active job test helpers.
@@ -55,7 +75,7 @@ module ActiveJob
     #     assert_enqueued_jobs 2
     #   end
     #
-    # If a block is passed, that block should cause the specified number of
+    # If a block is passed, that block will cause the specified number of
     # jobs to be enqueued.
     #
     #   def test_jobs_again
@@ -69,7 +89,7 @@ module ActiveJob
     #     end
     #   end
     #
-    # The number of times a specific job is enqueued can be asserted.
+    # The number of times a specific job was enqueued can be asserted.
     #
     #   def test_logging_job
     #     assert_enqueued_jobs 1, only: LoggingJob do
@@ -77,14 +97,32 @@ module ActiveJob
     #       HelloJob.perform_later('jeremy')
     #     end
     #   end
-    def assert_enqueued_jobs(number, only: nil)
+    #
+    # The number of times a job except specific class was enqueued can be asserted.
+    #
+    #   def test_logging_job
+    #     assert_enqueued_jobs 1, except: HelloJob do
+    #       LoggingJob.perform_later
+    #       HelloJob.perform_later('jeremy')
+    #     end
+    #   end
+    #
+    # The number of times a job is enqueued to a specific queue can also be asserted.
+    #
+    #   def test_logging_job
+    #     assert_enqueued_jobs 2, queue: 'default' do
+    #       LoggingJob.perform_later
+    #       HelloJob.perform_later('elfassy')
+    #     end
+    #   end
+    def assert_enqueued_jobs(number, only: nil, except: nil, queue: nil)
       if block_given?
-        original_count = enqueued_jobs_size(only: only)
+        original_count = enqueued_jobs_size(only: only, except: except, queue: queue)
         yield
-        new_count = enqueued_jobs_size(only: only)
+        new_count = enqueued_jobs_size(only: only, except: except, queue: queue)
         assert_equal number, new_count - original_count, "#{number} jobs expected, but #{new_count - original_count} were enqueued"
       else
-        actual_count = enqueued_jobs_size(only: only)
+        actual_count = enqueued_jobs_size(only: only, except: except, queue: queue)
         assert_equal number, actual_count, "#{number} jobs expected, but #{actual_count} were enqueued"
       end
     end
@@ -113,11 +151,19 @@ module ActiveJob
     #     end
     #   end
     #
+    # It can be asserted that no jobs except specific class are enqueued:
+    #
+    #   def test_no_logging
+    #     assert_no_enqueued_jobs except: HelloJob do
+    #       HelloJob.perform_later('jeremy')
+    #     end
+    #   end
+    #
     # Note: This assertion is simply a shortcut for:
     #
     #   assert_enqueued_jobs 0, &block
-    def assert_no_enqueued_jobs(only: nil, &block)
-      assert_enqueued_jobs 0, only: only, &block
+    def assert_no_enqueued_jobs(only: nil, except: nil, &block)
+      assert_enqueued_jobs 0, only: only, except: except, &block
     end
 
     # Asserts that the number of performed jobs matches the given number.
@@ -162,6 +208,16 @@ module ActiveJob
     #       end
     #     end
     #
+    # Also if the :except option is specified,
+    # then the job(s) except specific class will be performed.
+    #
+    #     def test_hello_job
+    #       assert_performed_jobs 1, except: LoggingJob do
+    #         HelloJob.perform_later('jeremy')
+    #         LoggingJob.perform_later
+    #       end
+    #     end
+    #
     # An array may also be specified, to support testing multiple jobs.
     #
     #     def test_hello_and_logging_jobs
@@ -173,10 +229,10 @@ module ActiveJob
     #         end
     #       end
     #     end
-    def assert_performed_jobs(number, only: nil)
+    def assert_performed_jobs(number, only: nil, except: nil)
       if block_given?
         original_count = performed_jobs.size
-        perform_enqueued_jobs(only: only) { yield }
+        perform_enqueued_jobs(only: only, except: except) { yield }
         new_count = performed_jobs.size
         assert_equal number, new_count - original_count,
           "#{number} jobs expected, but #{new_count - original_count} were performed"
@@ -214,11 +270,20 @@ module ActiveJob
     #     end
     #   end
     #
+    # Also if the :except option is specified,
+    # then the job(s) except specific class will not be performed.
+    #
+    #   def test_no_logging
+    #     assert_no_performed_jobs except: HelloJob do
+    #       HelloJob.perform_later('jeremy')
+    #     end
+    #   end
+    #
     # Note: This assertion is simply a shortcut for:
     #
     #   assert_performed_jobs 0, &block
-    def assert_no_performed_jobs(only: nil, &block)
-      assert_performed_jobs 0, only: only, &block
+    def assert_no_performed_jobs(only: nil, except: nil, &block)
+      assert_performed_jobs 0, only: only, except: except, &block
     end
 
     # Asserts that the job passed in the block has been enqueued with the given arguments.
@@ -232,16 +297,16 @@ module ActiveJob
     #       MyJob.set(wait_until: Date.tomorrow.noon).perform_later
     #     end
     #   end
-    def assert_enqueued_with(args = {})
+    def assert_enqueued_with(job: nil, args: nil, at: nil, queue: nil)
       original_enqueued_jobs_count = enqueued_jobs.count
-      args.assert_valid_keys(:job, :args, :at, :queue)
-      serialized_args = serialize_args_for_assertion(args)
+      expected = { job: job, args: args, at: at, queue: queue }.compact
+      serialized_args = serialize_args_for_assertion(expected)
       yield
       in_block_jobs = enqueued_jobs.drop(original_enqueued_jobs_count)
-      matching_job = in_block_jobs.find do |job|
-        serialized_args.all? { |key, value| value == job[key] }
+      matching_job = in_block_jobs.find do |in_block_job|
+        serialized_args.all? { |key, value| value == in_block_job[key] }
       end
-      assert matching_job, "No enqueued job found with #{args}"
+      assert matching_job, "No enqueued job found with #{expected}"
       instantiate_job(matching_job)
     end
 
@@ -256,69 +321,128 @@ module ActiveJob
     #       MyJob.set(wait_until: Date.tomorrow.noon).perform_later
     #     end
     #   end
-    def assert_performed_with(args = {})
+    def assert_performed_with(job: nil, args: nil, at: nil, queue: nil)
       original_performed_jobs_count = performed_jobs.count
-      args.assert_valid_keys(:job, :args, :at, :queue)
-      serialized_args = serialize_args_for_assertion(args)
+      expected = { job: job, args: args, at: at, queue: queue }.compact
+      serialized_args = serialize_args_for_assertion(expected)
       perform_enqueued_jobs { yield }
       in_block_jobs = performed_jobs.drop(original_performed_jobs_count)
-      matching_job = in_block_jobs.find do |job|
-        serialized_args.all? { |key, value| value == job[key] }
+      matching_job = in_block_jobs.find do |in_block_job|
+        serialized_args.all? { |key, value| value == in_block_job[key] }
       end
-      assert matching_job, "No performed job found with #{args}"
+      assert matching_job, "No performed job found with #{expected}"
       instantiate_job(matching_job)
     end
 
-    def perform_enqueued_jobs(only: nil)
+    # Performs all enqueued jobs in the duration of the block.
+    #
+    #   def test_perform_enqueued_jobs
+    #     perform_enqueued_jobs do
+    #       MyJob.perform_later(1, 2, 3)
+    #     end
+    #     assert_performed_jobs 1
+    #   end
+    #
+    # This method also supports filtering. If the +:only+ option is specified,
+    # then only the listed job(s) will be performed.
+    #
+    #   def test_perform_enqueued_jobs_with_only
+    #     perform_enqueued_jobs(only: MyJob) do
+    #       MyJob.perform_later(1, 2, 3) # will be performed
+    #       HelloJob.perform_later(1, 2, 3) # will not be performed
+    #     end
+    #     assert_performed_jobs 1
+    #   end
+    #
+    # Also if the +:except+ option is specified,
+    # then the job(s) except specific class will be performed.
+    #
+    #   def test_perform_enqueued_jobs_with_except
+    #     perform_enqueued_jobs(except: HelloJob) do
+    #       MyJob.perform_later(1, 2, 3) # will be performed
+    #       HelloJob.perform_later(1, 2, 3) # will not be performed
+    #     end
+    #     assert_performed_jobs 1
+    #   end
+    #
+    def perform_enqueued_jobs(only: nil, except: nil)
+      validate_option(only: only, except: except)
       old_perform_enqueued_jobs = queue_adapter.perform_enqueued_jobs
       old_perform_enqueued_at_jobs = queue_adapter.perform_enqueued_at_jobs
       old_filter = queue_adapter.filter
+      old_reject = queue_adapter.reject
 
       begin
         queue_adapter.perform_enqueued_jobs = true
         queue_adapter.perform_enqueued_at_jobs = true
         queue_adapter.filter = only
+        queue_adapter.reject = except
         yield
       ensure
         queue_adapter.perform_enqueued_jobs = old_perform_enqueued_jobs
         queue_adapter.perform_enqueued_at_jobs = old_perform_enqueued_at_jobs
         queue_adapter.filter = old_filter
+        queue_adapter.reject = old_reject
       end
     end
 
+    # Accesses the queue_adapter set by ActiveJob::Base.
+    #
+    #   def test_assert_job_has_custom_queue_adapter_set
+    #     assert_instance_of CustomQueueAdapter, HelloJob.queue_adapter
+    #   end
     def queue_adapter
       ActiveJob::Base.queue_adapter
     end
 
     private
-      def clear_enqueued_jobs # :nodoc:
+      def clear_enqueued_jobs
         enqueued_jobs.clear
       end
 
-      def clear_performed_jobs # :nodoc:
+      def clear_performed_jobs
         performed_jobs.clear
       end
 
-      def enqueued_jobs_size(only: nil) # :nodoc:
-        if only
-          enqueued_jobs.count { |job| Array(only).include?(job.fetch(:job)) }
-        else
-          enqueued_jobs.count
+      def enqueued_jobs_size(only: nil, except: nil, queue: nil)
+        validate_option(only: only, except: except)
+        enqueued_jobs.count do |job|
+          job_class = job.fetch(:job)
+          if only
+            next false unless Array(only).include?(job_class)
+          elsif except
+            next false if Array(except).include?(job_class)
+          end
+          if queue
+            next false unless queue.to_s == job.fetch(:queue, job_class.queue_name)
+          end
+          true
         end
       end
 
-      def serialize_args_for_assertion(args) # :nodoc:
+      def serialize_args_for_assertion(args)
         args.dup.tap do |serialized_args|
           serialized_args[:args] = ActiveJob::Arguments.serialize(serialized_args[:args]) if serialized_args[:args]
           serialized_args[:at]   = serialized_args[:at].to_f if serialized_args[:at]
         end
       end
 
-      def instantiate_job(payload) # :nodoc:
+      def instantiate_job(payload)
         job = payload[:job].new(*payload[:args])
         job.scheduled_at = Time.at(payload[:at]) if payload.key?(:at)
         job.queue_name = payload[:queue]
         job
       end
+
+      def queue_adapter_changed_jobs
+        (ActiveJob::Base.descendants << ActiveJob::Base).select do |klass|
+          # only override explicitly set adapters, a quirk of `class_attribute`
+          klass.singleton_class.public_instance_methods(false).include?(:_queue_adapter)
+        end
+      end
+
+      def validate_option(only: nil, except: nil)
+        raise ArgumentError, "Cannot specify both `:only` and `:except` options." if only && except
+      end
   end
 end
diff --git a/activejob/lib/active_job/translation.rb b/activejob/lib/active_job/translation.rb
index 67e4cf4ab9..fb45c80d67 100644
--- a/activejob/lib/active_job/translation.rb
+++ b/activejob/lib/active_job/translation.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActiveJob
   module Translation #:nodoc:
     extend ActiveSupport::Concern
diff --git a/activejob/lib/active_job/version.rb b/activejob/lib/active_job/version.rb
index 971ba9fe0c..eae7da4d05 100644
--- a/activejob/lib/active_job/version.rb
+++ b/activejob/lib/active_job/version.rb
@@ -1,4 +1,6 @@
-require_relative 'gem_version'
+# frozen_string_literal: true
+
+require_relative "gem_version"
 
 module ActiveJob
   # Returns the version of the currently loaded Active Job as a <tt>Gem::Version</tt>
diff --git a/activejob/lib/rails/generators/job/job_generator.rb b/activejob/lib/rails/generators/job/job_generator.rb
index 6e43e4a269..69b4fe7d26 100644
--- a/activejob/lib/rails/generators/job/job_generator.rb
+++ b/activejob/lib/rails/generators/job/job_generator.rb
@@ -1,37 +1,39 @@
-require 'rails/generators/named_base'
+# frozen_string_literal: true
+
+require "rails/generators/named_base"
 
 module Rails # :nodoc:
   module Generators # :nodoc:
     class JobGenerator < Rails::Generators::NamedBase # :nodoc:
-      desc 'This generator creates an active job file at app/jobs'
+      desc "This generator creates an active job file at app/jobs"
 
-      class_option :queue, type: :string, default: 'default', desc: 'The queue name for the generated job'
+      class_option :queue, type: :string, default: "default", desc: "The queue name for the generated job"
 
-      check_class_collision suffix: 'Job'
+      check_class_collision suffix: "Job"
 
       hook_for :test_framework
 
       def self.default_generator_root
-        File.dirname(__FILE__)
+        __dir__
       end
 
       def create_job_file
-        template 'job.rb', File.join('app/jobs', class_path, "#{file_name}_job.rb")
+        template "job.rb", File.join("app/jobs", class_path, "#{file_name}_job.rb")
 
         in_root do
-          if self.behavior == :invoke && !File.exist?(application_job_file_name)
-            template 'application_job.rb', application_job_file_name
+          if behavior == :invoke && !File.exist?(application_job_file_name)
+            template "application_job.rb", application_job_file_name
           end
         end
       end
 
       private
         def application_job_file_name
-           @application_job_file_name ||= if mountable_engine?
-             "app/jobs/#{namespaced_path}/application_job.rb"
-           else
-             'app/jobs/application_job.rb'
-           end
+          @application_job_file_name ||= if mountable_engine?
+            "app/jobs/#{namespaced_path}/application_job.rb"
+          else
+            "app/jobs/application_job.rb"
+          end
         end
     end
   end
diff --git a/activejob/lib/rails/generators/job/templates/application_job.rb.tt b/activejob/lib/rails/generators/job/templates/application_job.rb.tt
new file mode 100644
index 0000000000..f93745a31a
--- /dev/null
+++ b/activejob/lib/rails/generators/job/templates/application_job.rb.tt
@@ -0,0 +1,9 @@
+<% module_namespacing do -%>
+class ApplicationJob < ActiveJob::Base
+  # Automatically retry jobs that encountered a deadlock
+  # retry_on ActiveRecord::Deadlocked
+
+  # Most jobs are safe to ignore if the underlying records are no longer available
+  # discard_on ActiveJob::DeserializationError
+end
+<% end -%>
diff --git a/activejob/lib/rails/generators/job/templates/job.rb b/activejob/lib/rails/generators/job/templates/job.rb.tt
index 4ad2914a45..4ad2914a45 100644
--- a/activejob/lib/rails/generators/job/templates/job.rb
+++ b/activejob/lib/rails/generators/job/templates/job.rb.tt
diff --git a/activejob/test/adapters/async.rb b/activejob/test/adapters/async.rb
index 08eb9658cd..a4fed7c2f7 100644
--- a/activejob/test/adapters/async.rb
+++ b/activejob/test/adapters/async.rb
@@ -1,2 +1,4 @@
+# frozen_string_literal: true
+
 ActiveJob::Base.queue_adapter = :async
 ActiveJob::Base.queue_adapter.immediate = true
diff --git a/activejob/test/adapters/backburner.rb b/activejob/test/adapters/backburner.rb
index 65d05f850b..bc34c78e9c 100644
--- a/activejob/test/adapters/backburner.rb
+++ b/activejob/test/adapters/backburner.rb
@@ -1,3 +1,5 @@
-require 'support/backburner/inline'
+# frozen_string_literal: true
 
-ActiveJob::Base.queue_adapter = :backburner
\ No newline at end of file
+require "support/backburner/inline"
+
+ActiveJob::Base.queue_adapter = :backburner
diff --git a/activejob/test/adapters/delayed_job.rb b/activejob/test/adapters/delayed_job.rb
index afd9c9deb7..904b4c3f90 100644
--- a/activejob/test/adapters/delayed_job.rb
+++ b/activejob/test/adapters/delayed_job.rb
@@ -1,7 +1,8 @@
+# frozen_string_literal: true
+
 ActiveJob::Base.queue_adapter = :delayed_job
 
-$LOAD_PATH << File.dirname(__FILE__) + "/../support/delayed_job"
+$LOAD_PATH << File.expand_path("../support/delayed_job", __dir__)
 
 Delayed::Worker.delay_jobs = false
 Delayed::Worker.backend    = :test
-
diff --git a/activejob/test/adapters/inline.rb b/activejob/test/adapters/inline.rb
index e0092552c4..b1ddcb28f1 100644
--- a/activejob/test/adapters/inline.rb
+++ b/activejob/test/adapters/inline.rb
@@ -1 +1,3 @@
-ActiveJob::Base.queue_adapter = :inline
\ No newline at end of file
+# frozen_string_literal: true
+
+ActiveJob::Base.queue_adapter = :inline
diff --git a/activejob/test/adapters/qu.rb b/activejob/test/adapters/qu.rb
index 7728c843b4..5b471fa347 100644
--- a/activejob/test/adapters/qu.rb
+++ b/activejob/test/adapters/qu.rb
@@ -1,3 +1,5 @@
-require 'qu-immediate'
+# frozen_string_literal: true
+
+require "qu-immediate"
 
 ActiveJob::Base.queue_adapter = :qu
diff --git a/activejob/test/adapters/que.rb b/activejob/test/adapters/que.rb
index e6abc57457..af77b0d4d1 100644
--- a/activejob/test/adapters/que.rb
+++ b/activejob/test/adapters/que.rb
@@ -1,4 +1,6 @@
-require 'support/que/inline'
+# frozen_string_literal: true
+
+require "support/que/inline"
 
 ActiveJob::Base.queue_adapter = :que
 Que.mode = :sync
diff --git a/activejob/test/adapters/queue_classic.rb b/activejob/test/adapters/queue_classic.rb
index ad5ced3cc2..73902a5e62 100644
--- a/activejob/test/adapters/queue_classic.rb
+++ b/activejob/test/adapters/queue_classic.rb
@@ -1,2 +1,4 @@
-require 'support/queue_classic/inline'
+# frozen_string_literal: true
+
+require "support/queue_classic/inline"
 ActiveJob::Base.queue_adapter = :queue_classic
diff --git a/activejob/test/adapters/resque.rb b/activejob/test/adapters/resque.rb
index af7080358d..ad84a49372 100644
--- a/activejob/test/adapters/resque.rb
+++ b/activejob/test/adapters/resque.rb
@@ -1,2 +1,4 @@
+# frozen_string_literal: true
+
 ActiveJob::Base.queue_adapter = :resque
 Resque.inline = true
diff --git a/activejob/test/adapters/sidekiq.rb b/activejob/test/adapters/sidekiq.rb
index cd9d2034de..7df1c36488 100644
--- a/activejob/test/adapters/sidekiq.rb
+++ b/activejob/test/adapters/sidekiq.rb
@@ -1,2 +1,4 @@
-require 'sidekiq/testing/inline'
+# frozen_string_literal: true
+
+require "sidekiq/testing/inline"
 ActiveJob::Base.queue_adapter = :sidekiq
diff --git a/activejob/test/adapters/sneakers.rb b/activejob/test/adapters/sneakers.rb
index 204166a700..38d82aa778 100644
--- a/activejob/test/adapters/sneakers.rb
+++ b/activejob/test/adapters/sneakers.rb
@@ -1,2 +1,4 @@
-require 'support/sneakers/inline'
+# frozen_string_literal: true
+
+require "support/sneakers/inline"
 ActiveJob::Base.queue_adapter = :sneakers
diff --git a/activejob/test/adapters/sucker_punch.rb b/activejob/test/adapters/sucker_punch.rb
index d2d1712946..04bad984d4 100644
--- a/activejob/test/adapters/sucker_punch.rb
+++ b/activejob/test/adapters/sucker_punch.rb
@@ -1,2 +1,4 @@
-require 'sucker_punch/testing/inline'
+# frozen_string_literal: true
+
+require "sucker_punch/testing/inline"
 ActiveJob::Base.queue_adapter = :sucker_punch
diff --git a/activejob/test/adapters/test.rb b/activejob/test/adapters/test.rb
index 7180b38a57..0a1367dacf 100644
--- a/activejob/test/adapters/test.rb
+++ b/activejob/test/adapters/test.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 ActiveJob::Base.queue_adapter = :test
 ActiveJob::Base.queue_adapter.perform_enqueued_jobs = true
 ActiveJob::Base.queue_adapter.perform_enqueued_at_jobs = true
diff --git a/activejob/test/cases/adapter_test.rb b/activejob/test/cases/adapter_test.rb
index 6d75ae9a7c..2c179b2d38 100644
--- a/activejob/test/cases/adapter_test.rb
+++ b/activejob/test/cases/adapter_test.rb
@@ -1,4 +1,6 @@
-require 'helper'
+# frozen_string_literal: true
+
+require "helper"
 
 class AdapterTest < ActiveSupport::TestCase
   test "should load #{ENV['AJ_ADAPTER']} adapter" do
diff --git a/activejob/test/cases/argument_serialization_test.rb b/activejob/test/cases/argument_serialization_test.rb
index 59dc3d7f78..7e7f854da0 100644
--- a/activejob/test/cases/argument_serialization_test.rb
+++ b/activejob/test/cases/argument_serialization_test.rb
@@ -1,25 +1,27 @@
-require 'helper'
-require 'active_job/arguments'
-require 'models/person'
-require 'active_support/core_ext/hash/indifferent_access'
-require 'jobs/kwargs_job'
+# frozen_string_literal: true
+
+require "helper"
+require "active_job/arguments"
+require "models/person"
+require "active_support/core_ext/hash/indifferent_access"
+require "jobs/kwargs_job"
 
 class ArgumentSerializationTest < ActiveSupport::TestCase
   setup do
-    @person = Person.find('5')
+    @person = Person.find("5")
   end
 
   [ nil, 1, 1.0, 1_000_000_000_000_000_000_000,
-    'a', true, false, BigDecimal.new(5),
-    [ 1, 'a' ],
-    { 'a' => 1 }
+    "a", true, false, BigDecimal(5),
+    [ 1, "a" ],
+    { "a" => 1 }
   ].each do |arg|
-    test "serializes #{arg.class} verbatim" do
+    test "serializes #{arg.class} - #{arg} verbatim" do
       assert_arguments_unchanged arg
     end
   end
 
-  [ :a, Object.new, self, Person.find('5').to_gid ].each do |arg|
+  [ :a, Object.new, self, Person.find("5").to_gid ].each do |arg|
     test "does not serialize #{arg.class}" do
       assert_raises ActiveJob::SerializationError do
         ActiveJob::Arguments.serialize [ arg ]
@@ -31,22 +33,22 @@ class ArgumentSerializationTest < ActiveSupport::TestCase
     end
   end
 
-  test 'should convert records to Global IDs' do
+  test "should convert records to Global IDs" do
     assert_arguments_roundtrip [@person]
   end
 
-  test 'should dive deep into arrays and hashes' do
+  test "should dive deep into arrays and hashes" do
     assert_arguments_roundtrip [3, [@person]]
-    assert_arguments_roundtrip [{ 'a' => @person }]
+    assert_arguments_roundtrip [{ "a" => @person }]
   end
 
-  test 'should maintain string and symbol keys' do
+  test "should maintain string and symbol keys" do
     assert_arguments_roundtrip([a: 1, "b" => 2])
   end
 
-  test 'should maintain hash with indifferent access' do
+  test "should maintain hash with indifferent access" do
     symbol_key = { a: 1 }
-    string_key = { 'a' => 1 }
+    string_key = { "a" => 1 }
     indifferent_access = { a: 1 }.with_indifferent_access
 
     assert_not_instance_of ActiveSupport::HashWithIndifferentAccess, perform_round_trip([symbol_key]).first
@@ -54,26 +56,26 @@ class ArgumentSerializationTest < ActiveSupport::TestCase
     assert_instance_of ActiveSupport::HashWithIndifferentAccess, perform_round_trip([indifferent_access]).first
   end
 
-  test 'should disallow non-string/symbol hash keys' do
+  test "should disallow non-string/symbol hash keys" do
     assert_raises ActiveJob::SerializationError do
       ActiveJob::Arguments.serialize [ { 1 => 2 } ]
     end
 
     assert_raises ActiveJob::SerializationError do
-      ActiveJob::Arguments.serialize [ { :a => [{ 2 => 3 }] } ]
+      ActiveJob::Arguments.serialize [ { a: [{ 2 => 3 }] } ]
     end
   end
 
-  test 'should not allow reserved hash keys' do
-    ['_aj_globalid', :_aj_globalid, '_aj_symbol_keys', :_aj_symbol_keys,
-     '_aj_hash_with_indifferent_access', :_aj_hash_with_indifferent_access].each do |key|
+  test "should not allow reserved hash keys" do
+    ["_aj_globalid", :_aj_globalid, "_aj_symbol_keys", :_aj_symbol_keys,
+     "_aj_hash_with_indifferent_access", :_aj_hash_with_indifferent_access].each do |key|
       assert_raises ActiveJob::SerializationError do
         ActiveJob::Arguments.serialize [key => 1]
       end
     end
   end
 
-  test 'should not allow non-primitive objects' do
+  test "should not allow non-primitive objects" do
     assert_raises ActiveJob::SerializationError do
       ActiveJob::Arguments.serialize [Object.new]
     end
@@ -83,17 +85,17 @@ class ArgumentSerializationTest < ActiveSupport::TestCase
     end
   end
 
-  test 'allows for keyword arguments' do
+  test "allows for keyword arguments" do
     KwargsJob.perform_later(argument: 2)
 
     assert_equal "Job with argument: 2", JobBuffer.last_value
   end
 
-  test 'raises a friendly SerializationError for records without ids' do
+  test "raises a friendly SerializationError for records without ids" do
     err = assert_raises ActiveJob::SerializationError do
       ActiveJob::Arguments.serialize [Person.new(nil)]
     end
-    assert_match 'Unable to serialize Person without an id.', err.message
+    assert_match "Unable to serialize Person without an id.", err.message
   end
 
   private
diff --git a/activejob/test/cases/callbacks_test.rb b/activejob/test/cases/callbacks_test.rb
index 9af2380767..df6ce16858 100644
--- a/activejob/test/cases/callbacks_test.rb
+++ b/activejob/test/cases/callbacks_test.rb
@@ -1,10 +1,12 @@
-require 'helper'
-require 'jobs/callback_job'
+# frozen_string_literal: true
 
-require 'active_support/core_ext/object/inclusion'
+require "helper"
+require "jobs/callback_job"
+
+require "active_support/core_ext/object/inclusion"
 
 class CallbacksTest < ActiveSupport::TestCase
-  test 'perform callbacks' do
+  test "perform callbacks" do
     performed_callback_job = CallbackJob.new("A-JOB-ID")
     performed_callback_job.perform_now
     assert "CallbackJob ran before_perform".in? performed_callback_job.history
@@ -13,7 +15,7 @@ class CallbacksTest < ActiveSupport::TestCase
     assert "CallbackJob ran around_perform_stop".in? performed_callback_job.history
   end
 
-  test 'enqueue callbacks' do
+  test "enqueue callbacks" do
     enqueued_callback_job = CallbackJob.perform_later
     assert "CallbackJob ran before_enqueue".in? enqueued_callback_job.history
     assert "CallbackJob ran after_enqueue".in? enqueued_callback_job.history
diff --git a/activejob/test/cases/exceptions_test.rb b/activejob/test/cases/exceptions_test.rb
new file mode 100644
index 0000000000..22fed0a808
--- /dev/null
+++ b/activejob/test/cases/exceptions_test.rb
@@ -0,0 +1,109 @@
+# frozen_string_literal: true
+
+require "helper"
+require "jobs/retry_job"
+
+class ExceptionsTest < ActiveJob::TestCase
+  setup do
+    JobBuffer.clear
+    skip if ActiveJob::Base.queue_adapter.is_a?(ActiveJob::QueueAdapters::InlineAdapter)
+  end
+
+  test "successfully retry job throwing exception against defaults" do
+    perform_enqueued_jobs do
+      RetryJob.perform_later "DefaultsError", 5
+
+      assert_equal [
+        "Raised DefaultsError for the 1st time",
+        "Raised DefaultsError for the 2nd time",
+        "Raised DefaultsError for the 3rd time",
+        "Raised DefaultsError for the 4th time",
+        "Successfully completed job" ], JobBuffer.values
+    end
+  end
+
+  test "successfully retry job throwing exception against higher limit" do
+    perform_enqueued_jobs do
+      RetryJob.perform_later "ShortWaitTenAttemptsError", 9
+      assert_equal 9, JobBuffer.values.count
+    end
+  end
+
+  test "failed retry job when exception kept occurring against defaults" do
+    perform_enqueued_jobs do
+      begin
+        RetryJob.perform_later "DefaultsError", 6
+        assert_equal "Raised DefaultsError for the 5th time", JobBuffer.last_value
+      rescue DefaultsError
+        pass
+      end
+    end
+  end
+
+  test "failed retry job when exception kept occurring against higher limit" do
+    perform_enqueued_jobs do
+      begin
+        RetryJob.perform_later "ShortWaitTenAttemptsError", 11
+        assert_equal "Raised ShortWaitTenAttemptsError for the 10th time", JobBuffer.last_value
+      rescue ShortWaitTenAttemptsError
+        pass
+      end
+    end
+  end
+
+  test "discard job" do
+    perform_enqueued_jobs do
+      RetryJob.perform_later "DiscardableError", 2
+      assert_equal "Raised DiscardableError for the 1st time", JobBuffer.last_value
+    end
+  end
+
+  test "custom handling of job that exceeds retry attempts" do
+    perform_enqueued_jobs do
+      RetryJob.perform_later "CustomCatchError", 6
+      assert_equal "Dealt with a job that failed to retry in a custom way after 6 attempts. Message: CustomCatchError", JobBuffer.last_value
+    end
+  end
+
+  test "long wait job" do
+    travel_to Time.now
+
+    perform_enqueued_jobs do
+      assert_performed_with at: (Time.now + 3600.seconds).to_i do
+        RetryJob.perform_later "LongWaitError", 5
+      end
+    end
+  end
+
+  test "exponentially retrying job" do
+    travel_to Time.now
+
+    perform_enqueued_jobs do
+      assert_performed_with at: (Time.now + 3.seconds).to_i do
+        assert_performed_with at: (Time.now + 18.seconds).to_i do
+          assert_performed_with at: (Time.now + 83.seconds).to_i do
+            assert_performed_with at: (Time.now + 258.seconds).to_i do
+              RetryJob.perform_later "ExponentialWaitTenAttemptsError", 5
+            end
+          end
+        end
+      end
+    end
+  end
+
+  test "custom wait retrying job" do
+    travel_to Time.now
+
+    perform_enqueued_jobs do
+      assert_performed_with at: (Time.now + 2.seconds).to_i do
+        assert_performed_with at: (Time.now + 4.seconds).to_i do
+          assert_performed_with at: (Time.now + 6.seconds).to_i do
+            assert_performed_with at: (Time.now + 8.seconds).to_i do
+              RetryJob.perform_later "CustomWaitTenAttemptsError", 5
+            end
+          end
+        end
+      end
+    end
+  end
+end
diff --git a/activejob/test/cases/job_serialization_test.rb b/activejob/test/cases/job_serialization_test.rb
index fa94209889..440051c427 100644
--- a/activejob/test/cases/job_serialization_test.rb
+++ b/activejob/test/cases/job_serialization_test.rb
@@ -1,8 +1,10 @@
-require 'helper'
-require 'jobs/gid_job'
-require 'jobs/hello_job'
-require 'models/person'
-require 'json'
+# frozen_string_literal: true
+
+require "helper"
+require "jobs/gid_job"
+require "jobs/hello_job"
+require "models/person"
+require "json"
 
 class JobSerializationTest < ActiveSupport::TestCase
   setup do
@@ -10,16 +12,16 @@ class JobSerializationTest < ActiveSupport::TestCase
     @person = Person.find(5)
   end
 
-  test 'serialize job with gid' do
+  test "serialize job with gid" do
     GidJob.perform_later @person
     assert_equal "Person with ID: 5", JobBuffer.last_value
   end
 
-  test 'serialize includes current locale' do
-    assert_equal 'en', HelloJob.new.serialize['locale']
+  test "serialize includes current locale" do
+    assert_equal "en", HelloJob.new.serialize["locale"]
   end
 
-  test 'serialize and deserialize are symmetric' do
+  test "serialize and deserialize are symmetric" do
     # Round trip a job in memory only
     h1 = HelloJob.new
     h1.deserialize(h1.serialize)
@@ -33,15 +35,23 @@ class JobSerializationTest < ActiveSupport::TestCase
     assert_equal h1.serialize, h2.serialize
   end
 
-  test 'deserialize sets locale' do
+  test "deserialize sets locale" do
     job = HelloJob.new
-    job.deserialize 'locale' => 'es'
-    assert_equal 'es', job.locale
+    job.deserialize "locale" => "es"
+    assert_equal "es", job.locale
   end
 
-  test 'deserialize sets default locale' do
+  test "deserialize sets default locale" do
     job = HelloJob.new
     job.deserialize({})
-    assert_equal 'en', job.locale
+    assert_equal "en", job.locale
+  end
+
+  test "serialize stores provider_job_id" do
+    job = HelloJob.new
+    assert_nil job.serialize["provider_job_id"]
+
+    job.provider_job_id = "some value set by adapter"
+    assert_equal job.provider_job_id, job.serialize["provider_job_id"]
   end
 end
diff --git a/activejob/test/cases/logging_test.rb b/activejob/test/cases/logging_test.rb
index bf8a66432a..1f8c4a5573 100644
--- a/activejob/test/cases/logging_test.rb
+++ b/activejob/test/cases/logging_test.rb
@@ -1,11 +1,14 @@
-require 'helper'
+# frozen_string_literal: true
+
+require "helper"
 require "active_support/log_subscriber/test_helper"
-require 'active_support/core_ext/numeric/time'
-require 'jobs/hello_job'
-require 'jobs/logging_job'
-require 'jobs/overridden_logging_job'
-require 'jobs/nested_job'
-require 'models/person'
+require "active_support/core_ext/numeric/time"
+require "jobs/hello_job"
+require "jobs/logging_job"
+require "jobs/overridden_logging_job"
+require "jobs/nested_job"
+require "jobs/rescue_job"
+require "models/person"
 
 class LoggingTest < ActiveSupport::TestCase
   include ActiveSupport::LogSubscriber::TestHelper
@@ -89,21 +92,21 @@ class LoggingTest < ActiveSupport::TestCase
 
   def test_perform_job_logging
     LoggingJob.perform_later "Dummy"
-    assert_match(/Performing LoggingJob from .*? with arguments:.*Dummy/, @logger.messages)
+    assert_match(/Performing LoggingJob \(Job ID: .*?\) from .*? with arguments:.*Dummy/, @logger.messages)
     assert_match(/Dummy, here is it: Dummy/, @logger.messages)
-    assert_match(/Performed LoggingJob from .*? in .*ms/, @logger.messages)
+    assert_match(/Performed LoggingJob \(Job ID: .*?\) from .*? in .*ms/, @logger.messages)
   end
 
   def test_perform_nested_jobs_logging
     NestedJob.perform_later
     assert_match(/\[LoggingJob\] \[.*?\]/, @logger.messages)
     assert_match(/\[ActiveJob\] Enqueued NestedJob \(Job ID: .*\) to/, @logger.messages)
-    assert_match(/\[ActiveJob\] \[NestedJob\] \[NESTED-JOB-ID\] Performing NestedJob from/, @logger.messages)
+    assert_match(/\[ActiveJob\] \[NestedJob\] \[NESTED-JOB-ID\] Performing NestedJob \(Job ID: .*?\) from/, @logger.messages)
     assert_match(/\[ActiveJob\] \[NestedJob\] \[NESTED-JOB-ID\] Enqueued LoggingJob \(Job ID: .*?\) to .* with arguments: "NestedJob"/, @logger.messages)
-    assert_match(/\[ActiveJob\].*\[LoggingJob\] \[LOGGING-JOB-ID\] Performing LoggingJob from .* with arguments: "NestedJob"/, @logger.messages)
+    assert_match(/\[ActiveJob\].*\[LoggingJob\] \[LOGGING-JOB-ID\] Performing LoggingJob \(Job ID: .*?\) from .* with arguments: "NestedJob"/, @logger.messages)
     assert_match(/\[ActiveJob\].*\[LoggingJob\] \[LOGGING-JOB-ID\] Dummy, here is it: NestedJob/, @logger.messages)
-    assert_match(/\[ActiveJob\].*\[LoggingJob\] \[LOGGING-JOB-ID\] Performed LoggingJob from .* in/, @logger.messages)
-    assert_match(/\[ActiveJob\] \[NestedJob\] \[NESTED-JOB-ID\] Performed NestedJob from .* in/, @logger.messages)
+    assert_match(/\[ActiveJob\].*\[LoggingJob\] \[LOGGING-JOB-ID\] Performed LoggingJob \(Job ID: .*?\) from .* in/, @logger.messages)
+    assert_match(/\[ActiveJob\] \[NestedJob\] \[NESTED-JOB-ID\] Performed NestedJob \(Job ID: .*?\) from .* in/, @logger.messages)
   end
 
   def test_enqueue_at_job_logging
@@ -124,4 +127,11 @@ class LoggingTest < ActiveSupport::TestCase
     set_logger ::Logger.new(nil)
     OverriddenLoggingJob.perform_later "Dummy"
   end
+
+  def test_job_error_logging
+    RescueJob.perform_later "other"
+  rescue RescueJob::OtherError
+    assert_match(/Performing RescueJob \(Job ID: .*?\) from .*? with arguments:.*other/, @logger.messages)
+    assert_match(/Error performing RescueJob \(Job ID: .*?\) from .*? in .*ms: RescueJob::OtherError \(Bad hair\):\n.*\brescue_job\.rb:\d+:in `perform'/, @logger.messages)
+  end
 end
diff --git a/activejob/test/cases/queue_adapter_test.rb b/activejob/test/cases/queue_adapter_test.rb
index fb3fdc392f..e71cfa49cf 100644
--- a/activejob/test/cases/queue_adapter_test.rb
+++ b/activejob/test/cases/queue_adapter_test.rb
@@ -1,4 +1,6 @@
-require 'helper'
+# frozen_string_literal: true
+
+require "helper"
 
 module ActiveJob
   module QueueAdapters
@@ -15,36 +17,29 @@ module ActiveJob
 end
 
 class QueueAdapterTest < ActiveJob::TestCase
-  test 'should forbid nonsense arguments' do
+  test "should forbid nonsense arguments" do
     assert_raises(ArgumentError) { ActiveJob::Base.queue_adapter = Mutex }
     assert_raises(ArgumentError) { ActiveJob::Base.queue_adapter = Mutex.new }
   end
 
-  test 'should warn on passing an adapter class' do
-    klass = Class.new do
-      def self.name
-        'fake'
-      end
-
-      def enqueue(*); end
-      def enqueue_at(*); end
-    end
-
-    assert_deprecated { ActiveJob::Base.queue_adapter = klass }
-  end
-
-  test 'should allow overriding the queue_adapter at the child class level without affecting the parent or its sibling' do
+  test "should allow overriding the queue_adapter at the child class level without affecting the parent or its sibling" do
+    ActiveJob::Base.disable_test_adapter
     base_queue_adapter = ActiveJob::Base.queue_adapter
 
     child_job_one = Class.new(ActiveJob::Base)
+    assert_equal child_job_one.queue_adapter_name, ActiveJob::Base.queue_adapter_name
+
     child_job_one.queue_adapter = :stub_one
 
     assert_not_equal ActiveJob::Base.queue_adapter, child_job_one.queue_adapter
+    assert_equal "stub_one", child_job_one.queue_adapter_name
     assert_kind_of ActiveJob::QueueAdapters::StubOneAdapter, child_job_one.queue_adapter
 
     child_job_two = Class.new(ActiveJob::Base)
     child_job_two.queue_adapter = :stub_two
 
+    assert_equal "stub_two", child_job_two.queue_adapter_name
+
     assert_kind_of ActiveJob::QueueAdapters::StubTwoAdapter, child_job_two.queue_adapter
     assert_kind_of ActiveJob::QueueAdapters::StubOneAdapter, child_job_one.queue_adapter, "child_job_one's queue adapter should remain unchanged"
     assert_equal base_queue_adapter, ActiveJob::Base.queue_adapter, "ActiveJob::Base's queue adapter should remain unchanged"
diff --git a/activejob/test/cases/queue_naming_test.rb b/activejob/test/cases/queue_naming_test.rb
index 898016a704..b64a38f91e 100644
--- a/activejob/test/cases/queue_naming_test.rb
+++ b/activejob/test/cases/queue_naming_test.rb
@@ -1,14 +1,16 @@
-require 'helper'
-require 'jobs/hello_job'
-require 'jobs/logging_job'
-require 'jobs/nested_job'
+# frozen_string_literal: true
+
+require "helper"
+require "jobs/hello_job"
+require "jobs/logging_job"
+require "jobs/nested_job"
 
 class QueueNamingTest < ActiveSupport::TestCase
-  test 'name derived from base' do
+  test "name derived from base" do
     assert_equal "default", HelloJob.queue_name
   end
 
-  test 'uses given queue name job' do
+  test "uses given queue name job" do
     original_queue_name = HelloJob.queue_name
 
     begin
@@ -19,7 +21,7 @@ class QueueNamingTest < ActiveSupport::TestCase
     end
   end
 
-  test 'allows a blank queue name' do
+  test "allows a blank queue name" do
     original_queue_name = HelloJob.queue_name
 
     begin
@@ -30,7 +32,7 @@ class QueueNamingTest < ActiveSupport::TestCase
     end
   end
 
-  test 'does not use a nil queue name' do
+  test "does not use a nil queue name" do
     original_queue_name = HelloJob.queue_name
 
     begin
@@ -41,7 +43,7 @@ class QueueNamingTest < ActiveSupport::TestCase
     end
   end
 
-  test 'evals block given to queue_as to determine queue' do
+  test "evals block given to queue_as to determine queue" do
     original_queue_name = HelloJob.queue_name
 
     begin
@@ -52,42 +54,42 @@ class QueueNamingTest < ActiveSupport::TestCase
     end
   end
 
-  test 'can use arguments to determine queue_name in queue_as block' do
+  test "can use arguments to determine queue_name in queue_as block" do
     original_queue_name = HelloJob.queue_name
 
     begin
-      HelloJob.queue_as { self.arguments.first=='1' ? :one : :two }
-      assert_equal "one", HelloJob.new('1').queue_name
-      assert_equal "two", HelloJob.new('3').queue_name
+      HelloJob.queue_as { arguments.first == "1" ? :one : :two }
+      assert_equal "one", HelloJob.new("1").queue_name
+      assert_equal "two", HelloJob.new("3").queue_name
     ensure
       HelloJob.queue_name = original_queue_name
     end
   end
 
-  test 'queue_name_prefix prepended to the queue name with default delimiter' do
+  test "queue_name_prefix prepended to the queue name with default delimiter" do
     original_queue_name_prefix = ActiveJob::Base.queue_name_prefix
     original_queue_name = HelloJob.queue_name
 
     begin
-      ActiveJob::Base.queue_name_prefix = 'aj'
+      ActiveJob::Base.queue_name_prefix = "aj"
       HelloJob.queue_as :low
-      assert_equal 'aj_low', HelloJob.queue_name
+      assert_equal "aj_low", HelloJob.queue_name
     ensure
       ActiveJob::Base.queue_name_prefix = original_queue_name_prefix
       HelloJob.queue_name = original_queue_name
     end
   end
 
-  test 'queue_name_prefix prepended to the queue name with custom delimiter' do
+  test "queue_name_prefix prepended to the queue name with custom delimiter" do
     original_queue_name_prefix = ActiveJob::Base.queue_name_prefix
     original_queue_name_delimiter = ActiveJob::Base.queue_name_delimiter
     original_queue_name = HelloJob.queue_name
 
     begin
-      ActiveJob::Base.queue_name_delimiter = '.'
-      ActiveJob::Base.queue_name_prefix = 'aj'
+      ActiveJob::Base.queue_name_delimiter = "."
+      ActiveJob::Base.queue_name_prefix = "aj"
       HelloJob.queue_as :low
-      assert_equal 'aj.low', HelloJob.queue_name
+      assert_equal "aj.low", HelloJob.queue_name
     ensure
       ActiveJob::Base.queue_name_prefix = original_queue_name_prefix
       ActiveJob::Base.queue_name_delimiter = original_queue_name_delimiter
@@ -95,7 +97,7 @@ class QueueNamingTest < ActiveSupport::TestCase
     end
   end
 
-  test 'uses queue passed to #set' do
+  test "uses queue passed to #set" do
     job = HelloJob.set(queue: :some_queue).perform_later
     assert_equal "some_queue", job.queue_name
   end
diff --git a/activejob/test/cases/queue_priority_test.rb b/activejob/test/cases/queue_priority_test.rb
index ca17b51dad..4b3006ae81 100644
--- a/activejob/test/cases/queue_priority_test.rb
+++ b/activejob/test/cases/queue_priority_test.rb
@@ -1,12 +1,14 @@
-require 'helper'
-require 'jobs/hello_job'
+# frozen_string_literal: true
+
+require "helper"
+require "jobs/hello_job"
 
 class QueuePriorityTest < ActiveSupport::TestCase
-  test 'priority unset by default' do
-    assert_equal nil, HelloJob.priority
+  test "priority unset by default" do
+    assert_nil HelloJob.priority
   end
 
-  test 'uses given priority' do
+  test "uses given priority" do
     original_priority = HelloJob.priority
 
     begin
@@ -17,7 +19,7 @@ class QueuePriorityTest < ActiveSupport::TestCase
     end
   end
 
-  test 'evals block given to priority to determine priority' do
+  test "evals block given to priority to determine priority" do
     original_priority = HelloJob.priority
 
     begin
@@ -28,19 +30,19 @@ class QueuePriorityTest < ActiveSupport::TestCase
     end
   end
 
-  test 'can use arguments to determine priority in priority block' do
+  test "can use arguments to determine priority in priority block" do
     original_priority = HelloJob.priority
 
     begin
-      HelloJob.queue_with_priority { self.arguments.first=='1' ? 99 : 11 }
-      assert_equal 99, HelloJob.new('1').priority
-      assert_equal 11, HelloJob.new('3').priority
+      HelloJob.queue_with_priority { arguments.first == "1" ? 99 : 11 }
+      assert_equal 99, HelloJob.new("1").priority
+      assert_equal 11, HelloJob.new("3").priority
     ensure
       HelloJob.priority = original_priority
     end
   end
 
-  test 'uses priority passed to #set' do
+  test "uses priority passed to #set" do
     job = HelloJob.set(priority: 123).perform_later
     assert_equal 123, job.priority
   end
diff --git a/activejob/test/cases/queuing_test.rb b/activejob/test/cases/queuing_test.rb
index 0eeabbf693..0e843b7215 100644
--- a/activejob/test/cases/queuing_test.rb
+++ b/activejob/test/cases/queuing_test.rb
@@ -1,24 +1,25 @@
-require 'helper'
-require 'jobs/hello_job'
-require 'active_support/core_ext/numeric/time'
+# frozen_string_literal: true
 
+require "helper"
+require "jobs/hello_job"
+require "active_support/core_ext/numeric/time"
 
 class QueuingTest < ActiveSupport::TestCase
   setup do
     JobBuffer.clear
   end
 
-  test 'run queued job' do
+  test "run queued job" do
     HelloJob.perform_later
     assert_equal "David says hello", JobBuffer.last_value
   end
 
-  test 'run queued job with arguments' do
+  test "run queued job with arguments" do
     HelloJob.perform_later "Jamie"
     assert_equal "Jamie says hello", JobBuffer.last_value
   end
 
-  test 'run queued job later' do
+  test "run queued job later" do
     begin
       result = HelloJob.set(wait_until: 1.second.ago).perform_later "Jamie"
       assert result
@@ -27,13 +28,12 @@ class QueuingTest < ActiveSupport::TestCase
     end
   end
 
-  test 'job returned by enqueue has the arguments available' do
+  test "job returned by enqueue has the arguments available" do
     job = HelloJob.perform_later "Jamie"
     assert_equal [ "Jamie" ], job.arguments
   end
 
-
-  test 'job returned by perform_at has the timestamp available' do
+  test "job returned by perform_at has the timestamp available" do
     begin
       job = HelloJob.set(wait_until: Time.utc(2014, 1, 1)).perform_later
       assert_equal Time.utc(2014, 1, 1).to_f, job.scheduled_at
diff --git a/activejob/test/cases/rescue_test.rb b/activejob/test/cases/rescue_test.rb
index 58c9ca8992..da9c87dbf0 100644
--- a/activejob/test/cases/rescue_test.rb
+++ b/activejob/test/cases/rescue_test.rb
@@ -1,34 +1,36 @@
-require 'helper'
-require 'jobs/rescue_job'
-require 'models/person'
+# frozen_string_literal: true
+
+require "helper"
+require "jobs/rescue_job"
+require "models/person"
 
 class RescueTest < ActiveSupport::TestCase
   setup do
     JobBuffer.clear
   end
 
-  test 'rescue perform exception with retry' do
+  test "rescue perform exception with retry" do
     job = RescueJob.new("david")
     job.perform_now
     assert_equal [ "rescued from ArgumentError", "performed beautifully" ], JobBuffer.values
   end
 
-  test 'let through unhandled perform exception' do
+  test "let through unhandled perform exception" do
     job = RescueJob.new("other")
     assert_raises(RescueJob::OtherError) do
       job.perform_now
     end
   end
 
-  test 'rescue from deserialization errors' do
+  test "rescue from deserialization errors" do
     RescueJob.perform_later Person.new(404)
-    assert_includes JobBuffer.values, 'rescued from DeserializationError'
-    assert_includes JobBuffer.values, 'DeserializationError original exception was Person::RecordNotFound'
-    assert_not_includes JobBuffer.values, 'performed beautifully'
+    assert_includes JobBuffer.values, "rescued from DeserializationError"
+    assert_includes JobBuffer.values, "DeserializationError original exception was Person::RecordNotFound"
+    assert_not_includes JobBuffer.values, "performed beautifully"
   end
 
   test "should not wrap DeserializationError in DeserializationError" do
     RescueJob.perform_later [Person.new(404)]
-    assert_includes JobBuffer.values, 'DeserializationError original exception was Person::RecordNotFound'
+    assert_includes JobBuffer.values, "DeserializationError original exception was Person::RecordNotFound"
   end
 end
diff --git a/activejob/test/cases/test_case_test.rb b/activejob/test/cases/test_case_test.rb
index 616454a4b6..4ae2add3a8 100644
--- a/activejob/test/cases/test_case_test.rb
+++ b/activejob/test/cases/test_case_test.rb
@@ -1,7 +1,9 @@
-require 'helper'
-require 'jobs/hello_job'
-require 'jobs/logging_job'
-require 'jobs/nested_job'
+# frozen_string_literal: true
+
+require "helper"
+require "jobs/hello_job"
+require "jobs/logging_job"
+require "jobs/nested_job"
 
 class ActiveJobTestCaseTest < ActiveJob::TestCase
   # this tests that this job class doesn't get its adapter set.
@@ -9,7 +11,7 @@ class ActiveJobTestCaseTest < ActiveJob::TestCase
   # the `class_attribute` inheritance
   class TestClassAttributeInheritanceJob < ActiveJob::Base
     def self.queue_adapter=(*)
-      raise 'Attempting to break `class_attribute` inheritance, bad!'
+      raise "Attempting to break `class_attribute` inheritance, bad!"
     end
   end
 
@@ -18,6 +20,6 @@ class ActiveJobTestCaseTest < ActiveJob::TestCase
   end
 
   def test_set_test_adapter
-    assert_kind_of ActiveJob::QueueAdapters::TestAdapter, self.queue_adapter
+    assert_kind_of ActiveJob::QueueAdapters::TestAdapter, queue_adapter
   end
 end
diff --git a/activejob/test/cases/test_helper_test.rb b/activejob/test/cases/test_helper_test.rb
index 3d863f5e65..66bcd8f3a0 100644
--- a/activejob/test/cases/test_helper_test.rb
+++ b/activejob/test/cases/test_helper_test.rb
@@ -1,17 +1,20 @@
-require 'helper'
-require 'active_support/core_ext/time'
-require 'active_support/core_ext/date'
-require 'jobs/hello_job'
-require 'jobs/logging_job'
-require 'jobs/nested_job'
-require 'jobs/rescue_job'
-require 'models/person'
+# frozen_string_literal: true
+
+require "helper"
+require "active_support/core_ext/time"
+require "active_support/core_ext/date"
+require "jobs/hello_job"
+require "jobs/logging_job"
+require "jobs/nested_job"
+require "jobs/rescue_job"
+require "jobs/inherited_job"
+require "models/person"
 
 class EnqueuedJobsTest < ActiveJob::TestCase
   def test_assert_enqueued_jobs
     assert_nothing_raised do
       assert_enqueued_jobs 1 do
-        HelloJob.perform_later('david')
+        HelloJob.perform_later("david")
       end
     end
   end
@@ -19,23 +22,23 @@ class EnqueuedJobsTest < ActiveJob::TestCase
   def test_repeated_enqueued_jobs_calls
     assert_nothing_raised do
       assert_enqueued_jobs 1 do
-        HelloJob.perform_later('abdelkader')
+        HelloJob.perform_later("abdelkader")
       end
     end
 
     assert_nothing_raised do
       assert_enqueued_jobs 2 do
-        HelloJob.perform_later('sean')
-        HelloJob.perform_later('yves')
+        HelloJob.perform_later("sean")
+        HelloJob.perform_later("yves")
       end
     end
   end
 
   def test_assert_enqueued_jobs_message
-    HelloJob.perform_later('sean')
+    HelloJob.perform_later("sean")
     e = assert_raises Minitest::Assertion do
       assert_enqueued_jobs 2 do
-        HelloJob.perform_later('sean')
+        HelloJob.perform_later("sean")
       end
     end
     assert_match "Expected: 2", e.message
@@ -44,13 +47,13 @@ class EnqueuedJobsTest < ActiveJob::TestCase
 
   def test_assert_enqueued_jobs_with_no_block
     assert_nothing_raised do
-      HelloJob.perform_later('rafael')
+      HelloJob.perform_later("rafael")
       assert_enqueued_jobs 1
     end
 
     assert_nothing_raised do
-      HelloJob.perform_later('aaron')
-      HelloJob.perform_later('matthew')
+      HelloJob.perform_later("aaron")
+      HelloJob.perform_later("matthew")
       assert_enqueued_jobs 3
     end
   end
@@ -72,7 +75,7 @@ class EnqueuedJobsTest < ActiveJob::TestCase
   def test_assert_enqueued_jobs_too_few_sent
     error = assert_raise ActiveSupport::TestCase::Assertion do
       assert_enqueued_jobs 2 do
-        HelloJob.perform_later('xavier')
+        HelloJob.perform_later("xavier")
       end
     end
 
@@ -82,8 +85,8 @@ class EnqueuedJobsTest < ActiveJob::TestCase
   def test_assert_enqueued_jobs_too_many_sent
     error = assert_raise ActiveSupport::TestCase::Assertion do
       assert_enqueued_jobs 1 do
-        HelloJob.perform_later('cristian')
-        HelloJob.perform_later('guillermo')
+        HelloJob.perform_later("cristian")
+        HelloJob.perform_later("guillermo")
       end
     end
 
@@ -93,7 +96,7 @@ class EnqueuedJobsTest < ActiveJob::TestCase
   def test_assert_no_enqueued_jobs_failure
     error = assert_raise ActiveSupport::TestCase::Assertion do
       assert_no_enqueued_jobs do
-        HelloJob.perform_later('jeremy')
+        HelloJob.perform_later("jeremy")
       end
     end
 
@@ -103,12 +106,78 @@ class EnqueuedJobsTest < ActiveJob::TestCase
   def test_assert_enqueued_jobs_with_only_option
     assert_nothing_raised do
       assert_enqueued_jobs 1, only: HelloJob do
-        HelloJob.perform_later('jeremy')
+        HelloJob.perform_later("jeremy")
+        LoggingJob.perform_later
+        LoggingJob.perform_later
+      end
+    end
+  end
+
+  def test_assert_enqueued_jobs_with_except_option
+    assert_nothing_raised do
+      assert_enqueued_jobs 1, except: LoggingJob do
+        HelloJob.perform_later("jeremy")
+        LoggingJob.perform_later
         LoggingJob.perform_later
       end
     end
   end
 
+  def test_assert_enqueued_jobs_with_only_and_except_option
+    error = assert_raise ArgumentError do
+      assert_enqueued_jobs 1, only: HelloJob, except: HelloJob do
+        HelloJob.perform_later("jeremy")
+        LoggingJob.perform_later
+        LoggingJob.perform_later
+      end
+    end
+
+    assert_match(/`:only` and `:except`/, error.message)
+  end
+
+  def test_assert_enqueued_jobs_with_only_and_queue_option
+    assert_nothing_raised do
+      assert_enqueued_jobs 1, only: HelloJob, queue: :some_queue do
+        HelloJob.set(queue: :some_queue).perform_later
+        HelloJob.set(queue: :other_queue).perform_later
+        LoggingJob.perform_later
+      end
+    end
+  end
+
+  def test_assert_enqueued_jobs_with_except_and_queue_option
+    assert_nothing_raised do
+      assert_enqueued_jobs 1, except: LoggingJob, queue: :some_queue do
+        HelloJob.set(queue: :some_queue).perform_later
+        HelloJob.set(queue: :other_queue).perform_later
+        LoggingJob.perform_later
+      end
+    end
+  end
+
+  def test_assert_enqueued_jobs_with_only_and_except_and_queue_option
+    error = assert_raise ArgumentError do
+      assert_enqueued_jobs 1, only: HelloJob, except: HelloJob, queue: :some_queue do
+        HelloJob.set(queue: :some_queue).perform_later
+        HelloJob.set(queue: :other_queue).perform_later
+        LoggingJob.perform_later
+      end
+    end
+
+    assert_match(/`:only` and `:except`/, error.message)
+  end
+
+  def test_assert_enqueued_jobs_with_queue_option
+    assert_nothing_raised do
+      assert_enqueued_jobs 2, queue: :default do
+        HelloJob.perform_later
+        LoggingJob.perform_later
+        HelloJob.set(queue: :other_queue).perform_later
+        LoggingJob.set(queue: :other_queue).perform_later
+      end
+    end
+  end
+
   def test_assert_enqueued_jobs_with_only_option_and_none_sent
     error = assert_raise ActiveSupport::TestCase::Assertion do
       assert_enqueued_jobs 1, only: HelloJob do
@@ -119,10 +188,30 @@ class EnqueuedJobsTest < ActiveJob::TestCase
     assert_match(/1 .* but 0/, error.message)
   end
 
+  def test_assert_enqueued_jobs_with_except_option_and_none_sent
+    error = assert_raise ActiveSupport::TestCase::Assertion do
+      assert_enqueued_jobs 1, except: LoggingJob do
+        LoggingJob.perform_later
+      end
+    end
+
+    assert_match(/1 .* but 0/, error.message)
+  end
+
+  def test_assert_enqueued_jobs_with_only_and_except_option_and_none_sent
+    error = assert_raise ArgumentError do
+      assert_enqueued_jobs 1, only: HelloJob, except: HelloJob do
+        LoggingJob.perform_later
+      end
+    end
+
+    assert_match(/`:only` and `:except`/, error.message)
+  end
+
   def test_assert_enqueued_jobs_with_only_option_and_too_few_sent
     error = assert_raise ActiveSupport::TestCase::Assertion do
       assert_enqueued_jobs 5, only: HelloJob do
-        HelloJob.perform_later('jeremy')
+        HelloJob.perform_later("jeremy")
         4.times { LoggingJob.perform_later }
       end
     end
@@ -130,26 +219,90 @@ class EnqueuedJobsTest < ActiveJob::TestCase
     assert_match(/5 .* but 1/, error.message)
   end
 
+  def test_assert_enqueued_jobs_with_except_option_and_too_few_sent
+    error = assert_raise ActiveSupport::TestCase::Assertion do
+      assert_enqueued_jobs 5, except: LoggingJob do
+        HelloJob.perform_later("jeremy")
+        4.times { LoggingJob.perform_later }
+      end
+    end
+
+    assert_match(/5 .* but 1/, error.message)
+  end
+
+  def test_assert_enqueued_jobs_with_only_and_except_option_and_too_few_sent
+    error = assert_raise ArgumentError do
+      assert_enqueued_jobs 5, only: HelloJob, except: HelloJob do
+        HelloJob.perform_later("jeremy")
+        4.times { LoggingJob.perform_later }
+      end
+    end
+
+    assert_match(/`:only` and `:except`/, error.message)
+  end
+
   def test_assert_enqueued_jobs_with_only_option_and_too_many_sent
     error = assert_raise ActiveSupport::TestCase::Assertion do
       assert_enqueued_jobs 1, only: HelloJob do
-        2.times { HelloJob.perform_later('jeremy') }
+        2.times { HelloJob.perform_later("jeremy") }
       end
     end
 
     assert_match(/1 .* but 2/, error.message)
   end
 
+  def test_assert_enqueued_jobs_with_except_option_and_too_many_sent
+    error = assert_raise ActiveSupport::TestCase::Assertion do
+      assert_enqueued_jobs 1, except: LoggingJob do
+        2.times { HelloJob.perform_later("jeremy") }
+      end
+    end
+
+    assert_match(/1 .* but 2/, error.message)
+  end
+
+  def test_assert_enqueued_jobs_with_only_and_except_option_and_too_many_sent
+    error = assert_raise ArgumentError do
+      assert_enqueued_jobs 1, only: HelloJob, except: HelloJob do
+        2.times { HelloJob.perform_later("jeremy") }
+      end
+    end
+
+    assert_match(/`:only` and `:except`/, error.message)
+  end
+
   def test_assert_enqueued_jobs_with_only_option_as_array
     assert_nothing_raised do
       assert_enqueued_jobs 2, only: [HelloJob, LoggingJob] do
-        HelloJob.perform_later('jeremy')
-        LoggingJob.perform_later('stewie')
-        RescueJob.perform_later('david')
+        HelloJob.perform_later("jeremy")
+        LoggingJob.perform_later("stewie")
+        RescueJob.perform_later("david")
       end
     end
   end
 
+  def test_assert_enqueued_jobs_with_except_option_as_array
+    assert_nothing_raised do
+      assert_enqueued_jobs 1, except: [HelloJob, LoggingJob] do
+        HelloJob.perform_later("jeremy")
+        LoggingJob.perform_later("stewie")
+        RescueJob.perform_later("david")
+      end
+    end
+  end
+
+  def test_assert_enqueued_jobs_with_only_and_except_option_as_array
+    error = assert_raise ArgumentError do
+      assert_enqueued_jobs 2, only: [HelloJob, LoggingJob], except: [HelloJob, LoggingJob] do
+        HelloJob.perform_later("jeremy")
+        LoggingJob.perform_later("stewie")
+        RescueJob.perform_later("david")
+      end
+    end
+
+    assert_match(/`:only` and `:except`/, error.message)
+  end
+
   def test_assert_no_enqueued_jobs_with_only_option
     assert_nothing_raised do
       assert_no_enqueued_jobs only: HelloJob do
@@ -158,10 +311,39 @@ class EnqueuedJobsTest < ActiveJob::TestCase
     end
   end
 
+  def test_assert_no_enqueued_jobs_with_except_option
+    assert_nothing_raised do
+      assert_no_enqueued_jobs except: LoggingJob do
+        LoggingJob.perform_later
+      end
+    end
+  end
+
+  def test_assert_no_enqueued_jobs_with_only_and_except_option
+    error = assert_raise ArgumentError do
+      assert_no_enqueued_jobs only: HelloJob, except: HelloJob do
+        LoggingJob.perform_later
+      end
+    end
+
+    assert_match(/`:only` and `:except`/, error.message)
+  end
+
   def test_assert_no_enqueued_jobs_with_only_option_failure
     error = assert_raise ActiveSupport::TestCase::Assertion do
       assert_no_enqueued_jobs only: HelloJob do
-        HelloJob.perform_later('jeremy')
+        HelloJob.perform_later("jeremy")
+        LoggingJob.perform_later
+      end
+    end
+
+    assert_match(/0 .* but 1/, error.message)
+  end
+
+  def test_assert_no_enqueued_jobs_with_except_option_failure
+    error = assert_raise ActiveSupport::TestCase::Assertion do
+      assert_no_enqueued_jobs except: LoggingJob do
+        HelloJob.perform_later("jeremy")
         LoggingJob.perform_later
       end
     end
@@ -169,6 +351,17 @@ class EnqueuedJobsTest < ActiveJob::TestCase
     assert_match(/0 .* but 1/, error.message)
   end
 
+  def test_assert_no_enqueued_jobs_with_only_and_except_option_failure
+    error = assert_raise ArgumentError do
+      assert_no_enqueued_jobs only: HelloJob, except: HelloJob do
+        HelloJob.perform_later("jeremy")
+        LoggingJob.perform_later
+      end
+    end
+
+    assert_match(/`:only` and `:except`/, error.message)
+  end
+
   def test_assert_no_enqueued_jobs_with_only_option_as_array
     assert_nothing_raised do
       assert_no_enqueued_jobs only: [HelloJob, RescueJob] do
@@ -177,8 +370,27 @@ class EnqueuedJobsTest < ActiveJob::TestCase
     end
   end
 
+  def test_assert_no_enqueued_jobs_with_except_option_as_array
+    assert_nothing_raised do
+      assert_no_enqueued_jobs except: [HelloJob, RescueJob] do
+        HelloJob.perform_later
+        RescueJob.perform_later
+      end
+    end
+  end
+
+  def test_assert_no_enqueued_jobs_with_only_and_except_option_as_array
+    error = assert_raise ArgumentError do
+      assert_no_enqueued_jobs only: [HelloJob, RescueJob], except: [HelloJob, RescueJob] do
+        LoggingJob.perform_later
+      end
+    end
+
+    assert_match(/`:only` and `:except`/, error.message)
+  end
+
   def test_assert_enqueued_job
-    assert_enqueued_with(job: LoggingJob, queue: 'default') do
+    assert_enqueued_with(job: LoggingJob, queue: "default") do
       LoggingJob.set(wait_until: Date.tomorrow.noon).perform_later
     end
   end
@@ -190,19 +402,19 @@ class EnqueuedJobsTest < ActiveJob::TestCase
 
     assert_instance_of LoggingJob, job
     assert_in_delta 5.minutes.from_now, job.scheduled_at, 1
-    assert_equal 'default', job.queue_name
+    assert_equal "default", job.queue_name
     assert_equal [1, 2, 3], job.arguments
   end
 
   def test_assert_enqueued_job_failure
     assert_raise ActiveSupport::TestCase::Assertion do
-      assert_enqueued_with(job: LoggingJob, queue: 'default') do
+      assert_enqueued_with(job: LoggingJob, queue: "default") do
         NestedJob.perform_later
       end
     end
 
     error = assert_raise ActiveSupport::TestCase::Assertion do
-      assert_enqueued_with(job: NestedJob, queue: 'low') do
+      assert_enqueued_with(job: NestedJob, queue: "low") do
         NestedJob.perform_later
       end
     end
@@ -249,23 +461,31 @@ class EnqueuedJobsTest < ActiveJob::TestCase
       HelloJob.perform_later
     end
 
-    assert_equal 2, ActiveJob::Base.queue_adapter.enqueued_jobs.count
+    assert_equal 2, queue_adapter.enqueued_jobs.count
   end
 end
 
 class PerformedJobsTest < ActiveJob::TestCase
   def test_performed_enqueue_jobs_with_only_option_doesnt_leak_outside_the_block
-    assert_equal nil, queue_adapter.filter
+    assert_nil queue_adapter.filter
     perform_enqueued_jobs only: HelloJob do
       assert_equal HelloJob, queue_adapter.filter
     end
-    assert_equal nil, queue_adapter.filter
+    assert_nil queue_adapter.filter
+  end
+
+  def test_performed_enqueue_jobs_with_except_option_doesnt_leak_outside_the_block
+    assert_nil queue_adapter.reject
+    perform_enqueued_jobs except: HelloJob do
+      assert_equal HelloJob, queue_adapter.reject
+    end
+    assert_nil queue_adapter.reject
   end
 
   def test_assert_performed_jobs
     assert_nothing_raised do
       assert_performed_jobs 1 do
-        HelloJob.perform_later('david')
+        HelloJob.perform_later("david")
       end
     end
   end
@@ -273,23 +493,23 @@ class PerformedJobsTest < ActiveJob::TestCase
   def test_repeated_performed_jobs_calls
     assert_nothing_raised do
       assert_performed_jobs 1 do
-        HelloJob.perform_later('abdelkader')
+        HelloJob.perform_later("abdelkader")
       end
     end
 
     assert_nothing_raised do
       assert_performed_jobs 2 do
-        HelloJob.perform_later('sean')
-        HelloJob.perform_later('yves')
+        HelloJob.perform_later("sean")
+        HelloJob.perform_later("yves")
       end
     end
   end
 
   def test_assert_performed_jobs_message
-    HelloJob.perform_later('sean')
+    HelloJob.perform_later("sean")
     e = assert_raises Minitest::Assertion do
       assert_performed_jobs 2 do
-        HelloJob.perform_later('sean')
+        HelloJob.perform_later("sean")
       end
     end
     assert_match "Expected: 2", e.message
@@ -299,15 +519,15 @@ class PerformedJobsTest < ActiveJob::TestCase
   def test_assert_performed_jobs_with_no_block
     assert_nothing_raised do
       perform_enqueued_jobs do
-        HelloJob.perform_later('rafael')
+        HelloJob.perform_later("rafael")
       end
       assert_performed_jobs 1
     end
 
     assert_nothing_raised do
       perform_enqueued_jobs do
-        HelloJob.perform_later('aaron')
-        HelloJob.perform_later('matthew')
+        HelloJob.perform_later("aaron")
+        HelloJob.perform_later("matthew")
         assert_performed_jobs 3
       end
     end
@@ -330,7 +550,7 @@ class PerformedJobsTest < ActiveJob::TestCase
   def test_assert_performed_jobs_too_few_sent
     error = assert_raise ActiveSupport::TestCase::Assertion do
       assert_performed_jobs 2 do
-        HelloJob.perform_later('xavier')
+        HelloJob.perform_later("xavier")
       end
     end
 
@@ -340,8 +560,8 @@ class PerformedJobsTest < ActiveJob::TestCase
   def test_assert_performed_jobs_too_many_sent
     error = assert_raise ActiveSupport::TestCase::Assertion do
       assert_performed_jobs 1 do
-        HelloJob.perform_later('cristian')
-        HelloJob.perform_later('guillermo')
+        HelloJob.perform_later("cristian")
+        HelloJob.perform_later("guillermo")
       end
     end
 
@@ -351,7 +571,7 @@ class PerformedJobsTest < ActiveJob::TestCase
   def test_assert_no_performed_jobs_failure
     error = assert_raise ActiveSupport::TestCase::Assertion do
       assert_no_performed_jobs do
-        HelloJob.perform_later('jeremy')
+        HelloJob.perform_later("jeremy")
       end
     end
 
@@ -361,20 +581,62 @@ class PerformedJobsTest < ActiveJob::TestCase
   def test_assert_performed_jobs_with_only_option
     assert_nothing_raised do
       assert_performed_jobs 1, only: HelloJob do
-        HelloJob.perform_later('jeremy')
+        HelloJob.perform_later("jeremy")
+        LoggingJob.perform_later
+      end
+    end
+  end
+
+  def test_assert_performed_jobs_with_except_option
+    assert_nothing_raised do
+      assert_performed_jobs 1, except: LoggingJob do
+        HelloJob.perform_later("jeremy")
+        LoggingJob.perform_later
+      end
+    end
+  end
+
+  def test_assert_performed_jobs_with_only_and_except_option
+    error = assert_raise ArgumentError do
+      assert_performed_jobs 1, only: HelloJob, except: HelloJob do
+        HelloJob.perform_later("jeremy")
         LoggingJob.perform_later
       end
     end
+
+    assert_match(/`:only` and `:except`/, error.message)
   end
 
   def test_assert_performed_jobs_with_only_option_as_array
     assert_nothing_raised do
       assert_performed_jobs 2, only: [HelloJob, LoggingJob] do
-        HelloJob.perform_later('jeremy')
-        LoggingJob.perform_later('stewie')
-        RescueJob.perform_later('david')
+        HelloJob.perform_later("jeremy")
+        LoggingJob.perform_later("stewie")
+        RescueJob.perform_later("david")
+      end
+    end
+  end
+
+  def test_assert_performed_jobs_with_except_option_as_array
+    assert_nothing_raised do
+      assert_performed_jobs 1, except: [LoggingJob, RescueJob] do
+        HelloJob.perform_later("jeremy")
+        LoggingJob.perform_later("stewie")
+        RescueJob.perform_later("david")
+      end
+    end
+  end
+
+  def test_assert_performed_jobs_with_only_and_except_option_as_array
+    error = assert_raise ArgumentError do
+      assert_performed_jobs 2, only: [HelloJob, LoggingJob], except: [HelloJob, LoggingJob] do
+        HelloJob.perform_later("jeremy")
+        LoggingJob.perform_later("stewie")
+        RescueJob.perform_later("david")
       end
     end
+
+    assert_match(/`:only` and `:except`/, error.message)
   end
 
   def test_assert_performed_jobs_with_only_option_and_none_sent
@@ -387,10 +649,30 @@ class PerformedJobsTest < ActiveJob::TestCase
     assert_match(/1 .* but 0/, error.message)
   end
 
+  def test_assert_performed_jobs_with_except_option_and_none_sent
+    error = assert_raise ActiveSupport::TestCase::Assertion do
+      assert_performed_jobs 1, except: LoggingJob do
+        LoggingJob.perform_later
+      end
+    end
+
+    assert_match(/1 .* but 0/, error.message)
+  end
+
+  def test_assert_performed_jobs_with_only_and_except_option_and_none_sent
+    error = assert_raise ArgumentError do
+      assert_performed_jobs 1, only: HelloJob, except: HelloJob do
+        LoggingJob.perform_later
+      end
+    end
+
+    assert_match(/`:only` and `:except`/, error.message)
+  end
+
   def test_assert_performed_jobs_with_only_option_and_too_few_sent
     error = assert_raise ActiveSupport::TestCase::Assertion do
       assert_performed_jobs 5, only: HelloJob do
-        HelloJob.perform_later('jeremy')
+        HelloJob.perform_later("jeremy")
         4.times { LoggingJob.perform_later }
       end
     end
@@ -398,16 +680,58 @@ class PerformedJobsTest < ActiveJob::TestCase
     assert_match(/5 .* but 1/, error.message)
   end
 
+  def test_assert_performed_jobs_with_except_option_and_too_few_sent
+    error = assert_raise ActiveSupport::TestCase::Assertion do
+      assert_performed_jobs 5, except: LoggingJob do
+        HelloJob.perform_later("jeremy")
+        4.times { LoggingJob.perform_later }
+      end
+    end
+
+    assert_match(/5 .* but 1/, error.message)
+  end
+
+  def test_assert_performed_jobs_with_only_and_except_option_and_too_few_sent
+    error = assert_raise ArgumentError do
+      assert_performed_jobs 5, only: HelloJob, except: HelloJob do
+        HelloJob.perform_later("jeremy")
+        4.times { LoggingJob.perform_later }
+      end
+    end
+
+    assert_match(/`:only` and `:except`/, error.message)
+  end
+
   def test_assert_performed_jobs_with_only_option_and_too_many_sent
     error = assert_raise ActiveSupport::TestCase::Assertion do
       assert_performed_jobs 1, only: HelloJob do
-        2.times { HelloJob.perform_later('jeremy') }
+        2.times { HelloJob.perform_later("jeremy") }
       end
     end
 
     assert_match(/1 .* but 2/, error.message)
   end
 
+  def test_assert_performed_jobs_with_except_option_and_too_many_sent
+    error = assert_raise ActiveSupport::TestCase::Assertion do
+      assert_performed_jobs 1, except: LoggingJob do
+        2.times { HelloJob.perform_later("jeremy") }
+      end
+    end
+
+    assert_match(/1 .* but 2/, error.message)
+  end
+
+  def test_assert_performed_jobs_with_only_and_except_option_and_too_many_sent
+    error = assert_raise ArgumentError do
+      assert_performed_jobs 1, only: HelloJob, except: HelloJob do
+        2.times { HelloJob.perform_later("jeremy") }
+      end
+    end
+
+    assert_match(/`:only` and `:except`/, error.message)
+  end
+
   def test_assert_no_performed_jobs_with_only_option
     assert_nothing_raised do
       assert_no_performed_jobs only: HelloJob do
@@ -416,6 +740,24 @@ class PerformedJobsTest < ActiveJob::TestCase
     end
   end
 
+  def test_assert_no_performed_jobs_with_except_option
+    assert_nothing_raised do
+      assert_no_performed_jobs except: LoggingJob do
+        LoggingJob.perform_later
+      end
+    end
+  end
+
+  def test_assert_no_performed_jobs_with_only_and_except_option
+    error = assert_raise ArgumentError do
+      assert_no_performed_jobs only: HelloJob, except: HelloJob do
+        LoggingJob.perform_later
+      end
+    end
+
+    assert_match(/`:only` and `:except`/, error.message)
+  end
+
   def test_assert_no_performed_jobs_with_only_option_as_array
     assert_nothing_raised do
       assert_no_performed_jobs only: [HelloJob, RescueJob] do
@@ -424,10 +766,29 @@ class PerformedJobsTest < ActiveJob::TestCase
     end
   end
 
+  def test_assert_no_performed_jobs_with_except_option_as_array
+    assert_nothing_raised do
+      assert_no_performed_jobs except: [HelloJob, RescueJob] do
+        HelloJob.perform_later
+        RescueJob.perform_later
+      end
+    end
+  end
+
+  def test_assert_no_performed_jobs_with_only_and_except_option_as_array
+    error = assert_raise ArgumentError do
+      assert_no_performed_jobs only: [HelloJob, RescueJob], except: [HelloJob, RescueJob] do
+        LoggingJob.perform_later
+      end
+    end
+
+    assert_match(/`:only` and `:except`/, error.message)
+  end
+
   def test_assert_no_performed_jobs_with_only_option_failure
     error = assert_raise ActiveSupport::TestCase::Assertion do
       assert_no_performed_jobs only: HelloJob do
-        HelloJob.perform_later('jeremy')
+        HelloJob.perform_later("jeremy")
         LoggingJob.perform_later
       end
     end
@@ -435,21 +796,43 @@ class PerformedJobsTest < ActiveJob::TestCase
     assert_match(/0 .* but 1/, error.message)
   end
 
+  def test_assert_no_performed_jobs_with_except_option_failure
+    error = assert_raise ActiveSupport::TestCase::Assertion do
+      assert_no_performed_jobs except: LoggingJob do
+        HelloJob.perform_later("jeremy")
+        LoggingJob.perform_later
+      end
+    end
+
+    assert_match(/0 .* but 1/, error.message)
+  end
+
+  def test_assert_no_performed_jobs_with_only_and_except_option_failure
+    error = assert_raise ArgumentError do
+      assert_no_performed_jobs only: HelloJob, except: HelloJob do
+        HelloJob.perform_later("jeremy")
+        LoggingJob.perform_later
+      end
+    end
+
+    assert_match(/`:only` and `:except`/, error.message)
+  end
+
   def test_assert_performed_job
-    assert_performed_with(job: NestedJob, queue: 'default') do
+    assert_performed_with(job: NestedJob, queue: "default") do
       NestedJob.perform_later
     end
   end
 
   def test_assert_performed_job_returns
-    job = assert_performed_with(job: NestedJob, queue: 'default') do
+    job = assert_performed_with(job: NestedJob, queue: "default") do
       NestedJob.perform_later
     end
 
     assert_instance_of NestedJob, job
     assert_nil job.scheduled_at
     assert_equal [], job.arguments
-    assert_equal 'default', job.queue_name
+    assert_equal "default", job.queue_name
   end
 
   def test_assert_performed_job_failure
@@ -460,8 +843,8 @@ class PerformedJobsTest < ActiveJob::TestCase
     end
 
     assert_raise ActiveSupport::TestCase::Assertion do
-      assert_performed_with(job: HelloJob, queue: 'low') do
-        HelloJob.set(queue: 'important').perform_later
+      assert_performed_with(job: HelloJob, queue: "low") do
+        HelloJob.set(queue: "important").perform_later
       end
     end
   end
@@ -506,7 +889,7 @@ class PerformedJobsTest < ActiveJob::TestCase
       HelloJob.perform_later
     end
 
-    assert_equal 2, ActiveJob::Base.queue_adapter.performed_jobs.count
+    assert_equal 2, queue_adapter.performed_jobs.count
   end
 end
 
@@ -521,3 +904,26 @@ class OverrideQueueAdapterTest < ActiveJob::TestCase
     assert_instance_of CustomQueueAdapter, HelloJob.queue_adapter
   end
 end
+
+class InheritedJobTest < ActiveJob::TestCase
+  def test_queue_adapter_is_test_adapter
+    assert_instance_of ActiveJob::QueueAdapters::TestAdapter, InheritedJob.queue_adapter
+  end
+end
+
+class QueueAdapterJobTest < ActiveJob::TestCase
+  def before_setup
+    @original_autoload_paths = ActiveSupport::Dependencies.autoload_paths
+    ActiveSupport::Dependencies.autoload_paths = %w(test/jobs)
+    super
+  end
+
+  def after_teardown
+    ActiveSupport::Dependencies.autoload_paths = @original_autoload_paths
+    super
+  end
+
+  def test_queue_adapter_is_test_adapter
+    assert_instance_of ActiveJob::QueueAdapters::TestAdapter, QueueAdapterJob.queue_adapter
+  end
+end
diff --git a/activejob/test/cases/translation_test.rb b/activejob/test/cases/translation_test.rb
index d5e3aaf9e3..6a0d6d3e54 100644
--- a/activejob/test/cases/translation_test.rb
+++ b/activejob/test/cases/translation_test.rb
@@ -1,18 +1,20 @@
-require 'helper'
-require 'jobs/translated_hello_job'
+# frozen_string_literal: true
+
+require "helper"
+require "jobs/translated_hello_job"
 
 class TranslationTest < ActiveSupport::TestCase
   setup do
     JobBuffer.clear
     I18n.available_locales = [:en, :de]
-    @job = TranslatedHelloJob.new('Johannes')
+    @job = TranslatedHelloJob.new("Johannes")
   end
 
   teardown do
     I18n.available_locales = [:en]
   end
 
-  test 'it performs the job in the given locale' do
+  test "it performs the job in the given locale" do
     @job.locale = :de
     @job.perform_now
     assert_equal "Johannes says Guten Tag", JobBuffer.last_value
diff --git a/activejob/test/helper.rb b/activejob/test/helper.rb
index 54b6076f09..694232d7ef 100644
--- a/activejob/test/helper.rb
+++ b/activejob/test/helper.rb
@@ -1,16 +1,18 @@
-require 'active_job'
-require 'support/job_buffer'
+# frozen_string_literal: true
 
-ActiveSupport.halt_callback_chains_on_return_false = false
-GlobalID.app = 'aj'
+require "active_job"
+require "support/job_buffer"
 
-@adapter  = ENV['AJ_ADAPTER'] || 'inline'
+GlobalID.app = "aj"
 
-if ENV['AJ_INTEGRATION_TESTS']
-  require 'support/integration/helper'
+@adapter = ENV["AJ_ADAPTER"] || "inline"
+puts "Using #{@adapter}"
+
+if ENV["AJ_INTEGRATION_TESTS"]
+  require "support/integration/helper"
 else
   ActiveJob::Base.logger = Logger.new(nil)
   require "adapters/#{@adapter}"
 end
 
-require 'active_support/testing/autorun'
+require "active_support/testing/autorun"
diff --git a/activejob/test/integration/queuing_test.rb b/activejob/test/integration/queuing_test.rb
index 40f27500a5..32ef485c45 100644
--- a/activejob/test/integration/queuing_test.rb
+++ b/activejob/test/integration/queuing_test.rb
@@ -1,16 +1,19 @@
-require 'helper'
-require 'jobs/logging_job'
-require 'jobs/hello_job'
-require 'active_support/core_ext/numeric/time'
+# frozen_string_literal: true
+
+require "helper"
+require "jobs/logging_job"
+require "jobs/hello_job"
+require "jobs/provider_jid_job"
+require "active_support/core_ext/numeric/time"
 
 class QueuingTest < ActiveSupport::TestCase
-  test 'should run jobs enqueued on a listening queue' do
+  test "should run jobs enqueued on a listening queue" do
     TestJob.perform_later @id
     wait_for_jobs_to_finish_for(5.seconds)
     assert job_executed
   end
 
-  test 'should not run jobs queued on a non-listening queue' do
+  test "should not run jobs queued on a non-listening queue" do
     skip if adapter_is?(:inline, :async, :sucker_punch, :que)
     old_queue = TestJob.queue_name
 
@@ -24,17 +27,39 @@ class QueuingTest < ActiveSupport::TestCase
     end
   end
 
-  test 'should supply a wrapped class name to Sidekiq' do
+  test "should supply a wrapped class name to Sidekiq" do
     skip unless adapter_is?(:sidekiq)
     Sidekiq::Testing.fake! do
       ::HelloJob.perform_later
       hash = ActiveJob::QueueAdapters::SidekiqAdapter::JobWrapper.jobs.first
-      assert_equal "ActiveJob::QueueAdapters::SidekiqAdapter::JobWrapper", hash['class']
-      assert_equal "HelloJob", hash['wrapped']
+      assert_equal "ActiveJob::QueueAdapters::SidekiqAdapter::JobWrapper", hash["class"]
+      assert_equal "HelloJob", hash["wrapped"]
+    end
+  end
+
+  test "should access provider_job_id inside Sidekiq job" do
+    skip unless adapter_is?(:sidekiq)
+    Sidekiq::Testing.inline! do
+      job = ::ProviderJidJob.perform_later
+      assert_equal "Provider Job ID: #{job.provider_job_id}", JobBuffer.last_value
     end
   end
 
-  test 'should not run job enqueued in the future' do
+  test "should supply a wrapped class name to DelayedJob" do
+    skip unless adapter_is?(:delayed_job)
+    ::HelloJob.perform_later
+    job = Delayed::Job.first
+    assert_match(/HelloJob \[[0-9a-f-]+\] from DelayedJob\(default\) with arguments: \[\]/, job.name)
+  end
+
+  test "resque JobWrapper should have instance variable queue" do
+    skip unless adapter_is?(:resque)
+    job = ::HelloJob.set(wait: 5.seconds).perform_later
+    hash = Resque.decode(Resque.find_delayed_selection { true }[0])
+    assert_equal hash["queue"], job.queue_name
+  end
+
+  test "should not run job enqueued in the future" do
     begin
       TestJob.set(wait: 10.minutes).perform_later @id
       wait_for_jobs_to_finish_for(5.seconds)
@@ -44,7 +69,7 @@ class QueuingTest < ActiveSupport::TestCase
     end
   end
 
-  test 'should run job enqueued in the future at the specified time' do
+  test "should run job enqueued in the future at the specified time" do
     begin
       TestJob.set(wait: 5.seconds).perform_later @id
       wait_for_jobs_to_finish_for(2.seconds)
@@ -56,19 +81,19 @@ class QueuingTest < ActiveSupport::TestCase
     end
   end
 
-  test 'should supply a provider_job_id when available for immediate jobs' do
+  test "should supply a provider_job_id when available for immediate jobs" do
     skip unless adapter_is?(:async, :delayed_job, :sidekiq, :qu, :que, :queue_classic)
     test_job = TestJob.perform_later @id
-    assert test_job.provider_job_id, 'Provider job id should be set by provider'
+    assert test_job.provider_job_id, "Provider job id should be set by provider"
   end
 
-  test 'should supply a provider_job_id when available for delayed jobs' do
+  test "should supply a provider_job_id when available for delayed jobs" do
     skip unless adapter_is?(:async, :delayed_job, :sidekiq, :que, :queue_classic)
     delayed_test_job = TestJob.set(wait: 1.minute).perform_later @id
-    assert delayed_test_job.provider_job_id, 'Provider job id should by set for delayed jobs by provider'
+    assert delayed_test_job.provider_job_id, "Provider job id should by set for delayed jobs by provider"
   end
 
-  test 'current locale is kept while running perform_later' do
+  test "current locale is kept while running perform_later" do
     skip if adapter_is?(:inline)
 
     begin
@@ -78,14 +103,14 @@ class QueuingTest < ActiveSupport::TestCase
       TestJob.perform_later @id
       wait_for_jobs_to_finish_for(5.seconds)
       assert job_executed
-      assert_equal 'de', job_executed_in_locale
+      assert_equal "de", job_executed_in_locale
     ensure
       I18n.available_locales = [:en]
       I18n.locale = :en
     end
   end
 
-  test 'should run job with higher priority first' do
+  test "should run job with higher priority first" do
     skip unless adapter_is?(:delayed_job, :que)
 
     wait_until = Time.now + 3.seconds
diff --git a/activejob/lib/rails/generators/job/templates/application_job.rb b/activejob/test/jobs/application_job.rb
index 0b113b950e..d92ffddcb5 100644
--- a/activejob/lib/rails/generators/job/templates/application_job.rb
+++ b/activejob/test/jobs/application_job.rb
@@ -1,4 +1,4 @@
-<% module_namespacing do -%>
+# frozen_string_literal: true
+
 class ApplicationJob < ActiveJob::Base
 end
-<% end -%>
diff --git a/activejob/test/jobs/callback_job.rb b/activejob/test/jobs/callback_job.rb
index 891ed9464e..436cb55492 100644
--- a/activejob/test/jobs/callback_job.rb
+++ b/activejob/test/jobs/callback_job.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class CallbackJob < ActiveJob::Base
   before_perform ->(job) { job.history << "CallbackJob ran before_perform" }
   after_perform ->(job) { job.history << "CallbackJob ran after_perform" }
@@ -17,7 +19,6 @@ class CallbackJob < ActiveJob::Base
     job.history << "CallbackJob ran around_enqueue_stop"
   end
 
-
   def perform(person = "david")
     # NOTHING!
   end
@@ -25,5 +26,4 @@ class CallbackJob < ActiveJob::Base
   def history
     @history ||= []
   end
-
 end
diff --git a/activejob/test/jobs/gid_job.rb b/activejob/test/jobs/gid_job.rb
index e485bfa2dd..2136f57e05 100644
--- a/activejob/test/jobs/gid_job.rb
+++ b/activejob/test/jobs/gid_job.rb
@@ -1,8 +1,9 @@
-require_relative '../support/job_buffer'
+# frozen_string_literal: true
+
+require_relative "../support/job_buffer"
 
 class GidJob < ActiveJob::Base
   def perform(person)
     JobBuffer.add("Person with ID: #{person.id}")
   end
 end
-
diff --git a/activejob/test/jobs/hello_job.rb b/activejob/test/jobs/hello_job.rb
index 022fa58e4a..404df6150a 100644
--- a/activejob/test/jobs/hello_job.rb
+++ b/activejob/test/jobs/hello_job.rb
@@ -1,4 +1,6 @@
-require_relative '../support/job_buffer'
+# frozen_string_literal: true
+
+require_relative "../support/job_buffer"
 
 class HelloJob < ActiveJob::Base
   def perform(greeter = "David")
diff --git a/activejob/test/jobs/inherited_job.rb b/activejob/test/jobs/inherited_job.rb
new file mode 100644
index 0000000000..14f852ed06
--- /dev/null
+++ b/activejob/test/jobs/inherited_job.rb
@@ -0,0 +1,7 @@
+# frozen_string_literal: true
+
+require_relative "application_job"
+
+class InheritedJob < ApplicationJob
+  self.queue_adapter = :inline
+end
diff --git a/activejob/test/jobs/kwargs_job.rb b/activejob/test/jobs/kwargs_job.rb
index 2df17d15ae..b86b06bada 100644
--- a/activejob/test/jobs/kwargs_job.rb
+++ b/activejob/test/jobs/kwargs_job.rb
@@ -1,4 +1,6 @@
-require_relative '../support/job_buffer'
+# frozen_string_literal: true
+
+require_relative "../support/job_buffer"
 
 class KwargsJob < ActiveJob::Base
   def perform(argument: 1)
diff --git a/activejob/test/jobs/logging_job.rb b/activejob/test/jobs/logging_job.rb
index d84ed8589b..4605fa6937 100644
--- a/activejob/test/jobs/logging_job.rb
+++ b/activejob/test/jobs/logging_job.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class LoggingJob < ActiveJob::Base
   def perform(dummy)
     logger.info "Dummy, here is it: #{dummy}"
@@ -7,4 +9,3 @@ class LoggingJob < ActiveJob::Base
     "LOGGING-JOB-ID"
   end
 end
-
diff --git a/activejob/test/jobs/nested_job.rb b/activejob/test/jobs/nested_job.rb
index 8c4ec549a6..aafad0dba9 100644
--- a/activejob/test/jobs/nested_job.rb
+++ b/activejob/test/jobs/nested_job.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class NestedJob < ActiveJob::Base
   def perform
     LoggingJob.perform_later "NestedJob"
@@ -7,4 +9,3 @@ class NestedJob < ActiveJob::Base
     "NESTED-JOB-ID"
   end
 end
-
diff --git a/activejob/test/jobs/overridden_logging_job.rb b/activejob/test/jobs/overridden_logging_job.rb
index 2b17a65142..2ee363637d 100644
--- a/activejob/test/jobs/overridden_logging_job.rb
+++ b/activejob/test/jobs/overridden_logging_job.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class OverriddenLoggingJob < ActiveJob::Base
   def perform(dummy)
     logger.info "Dummy, here is it: #{dummy}"
diff --git a/activejob/test/jobs/provider_jid_job.rb b/activejob/test/jobs/provider_jid_job.rb
new file mode 100644
index 0000000000..dacd09afdc
--- /dev/null
+++ b/activejob/test/jobs/provider_jid_job.rb
@@ -0,0 +1,9 @@
+# frozen_string_literal: true
+
+require_relative "../support/job_buffer"
+
+class ProviderJidJob < ActiveJob::Base
+  def perform
+    JobBuffer.add("Provider Job ID: #{provider_job_id}")
+  end
+end
diff --git a/activejob/test/jobs/queue_adapter_job.rb b/activejob/test/jobs/queue_adapter_job.rb
new file mode 100644
index 0000000000..1c31a60ba2
--- /dev/null
+++ b/activejob/test/jobs/queue_adapter_job.rb
@@ -0,0 +1,5 @@
+# frozen_string_literal: true
+
+class QueueAdapterJob < ActiveJob::Base
+  self.queue_adapter = :inline
+end
diff --git a/activejob/test/jobs/queue_as_job.rb b/activejob/test/jobs/queue_as_job.rb
index 897aef52e5..0feee99e87 100644
--- a/activejob/test/jobs/queue_as_job.rb
+++ b/activejob/test/jobs/queue_as_job.rb
@@ -1,4 +1,6 @@
-require_relative '../support/job_buffer'
+# frozen_string_literal: true
+
+require_relative "../support/job_buffer"
 
 class QueueAsJob < ActiveJob::Base
   MY_QUEUE = :low_priority
diff --git a/activejob/test/jobs/rescue_job.rb b/activejob/test/jobs/rescue_job.rb
index 4f6376c850..d142cec1ea 100644
--- a/activejob/test/jobs/rescue_job.rb
+++ b/activejob/test/jobs/rescue_job.rb
@@ -1,16 +1,18 @@
-require_relative '../support/job_buffer'
+# frozen_string_literal: true
+
+require_relative "../support/job_buffer"
 
 class RescueJob < ActiveJob::Base
   class OtherError < StandardError; end
 
   rescue_from(ArgumentError) do
-    JobBuffer.add('rescued from ArgumentError')
+    JobBuffer.add("rescued from ArgumentError")
     arguments[0] = "DIFFERENT!"
     retry_job
   end
 
   rescue_from(ActiveJob::DeserializationError) do |e|
-    JobBuffer.add('rescued from DeserializationError')
+    JobBuffer.add("rescued from DeserializationError")
     JobBuffer.add("DeserializationError original exception was #{e.cause.class.name}")
   end
 
@@ -19,9 +21,9 @@ class RescueJob < ActiveJob::Base
     when "david"
       raise ArgumentError, "Hair too good"
     when "other"
-      raise OtherError
+      raise OtherError, "Bad hair"
     else
-      JobBuffer.add('performed beautifully')
+      JobBuffer.add("performed beautifully")
     end
   end
 end
diff --git a/activejob/test/jobs/retry_job.rb b/activejob/test/jobs/retry_job.rb
new file mode 100644
index 0000000000..9aa99d9a21
--- /dev/null
+++ b/activejob/test/jobs/retry_job.rb
@@ -0,0 +1,31 @@
+# frozen_string_literal: true
+
+require_relative "../support/job_buffer"
+require "active_support/core_ext/integer/inflections"
+
+class DefaultsError < StandardError; end
+class LongWaitError < StandardError; end
+class ShortWaitTenAttemptsError < StandardError; end
+class ExponentialWaitTenAttemptsError < StandardError; end
+class CustomWaitTenAttemptsError < StandardError; end
+class CustomCatchError < StandardError; end
+class DiscardableError < StandardError; end
+
+class RetryJob < ActiveJob::Base
+  retry_on DefaultsError
+  retry_on LongWaitError, wait: 1.hour, attempts: 10
+  retry_on ShortWaitTenAttemptsError, wait: 1.second, attempts: 10
+  retry_on ExponentialWaitTenAttemptsError, wait: :exponentially_longer, attempts: 10
+  retry_on CustomWaitTenAttemptsError, wait: ->(executions) { executions * 2 }, attempts: 10
+  retry_on(CustomCatchError) { |job, exception| JobBuffer.add("Dealt with a job that failed to retry in a custom way after #{job.arguments.second} attempts. Message: #{exception.message}") }
+  discard_on DiscardableError
+
+  def perform(raising, attempts)
+    if executions < attempts
+      JobBuffer.add("Raised #{raising} for the #{executions.ordinalize} time")
+      raise raising.constantize
+    else
+      JobBuffer.add("Successfully completed job")
+    end
+  end
+end
diff --git a/activejob/test/jobs/translated_hello_job.rb b/activejob/test/jobs/translated_hello_job.rb
index 9657cd3f54..a0a68b4040 100644
--- a/activejob/test/jobs/translated_hello_job.rb
+++ b/activejob/test/jobs/translated_hello_job.rb
@@ -1,8 +1,10 @@
-require_relative '../support/job_buffer'
+# frozen_string_literal: true
+
+require_relative "../support/job_buffer"
 
 class TranslatedHelloJob < ActiveJob::Base
   def perform(greeter = "David")
-    translations = { en: 'Hello', de: 'Guten Tag' }
+    translations = { en: "Hello", de: "Guten Tag" }
     hello        = translations[I18n.locale]
 
     JobBuffer.add("#{greeter} says #{hello}")
diff --git a/activejob/test/models/person.rb b/activejob/test/models/person.rb
index 76a8f40616..9a3bfab25f 100644
--- a/activejob/test/models/person.rb
+++ b/activejob/test/models/person.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Person
   class RecordNotFound < StandardError; end
 
@@ -6,7 +8,7 @@ class Person
   attr_reader :id
 
   def self.find(id)
-    raise RecordNotFound.new("Cannot find person with ID=404") if id.to_i==404
+    raise RecordNotFound.new("Cannot find person with ID=404") if id.to_i == 404
     new(id)
   end
 
diff --git a/activejob/test/support/backburner/inline.rb b/activejob/test/support/backburner/inline.rb
index f761b53e27..6c708c0b7b 100644
--- a/activejob/test/support/backburner/inline.rb
+++ b/activejob/test/support/backburner/inline.rb
@@ -1,8 +1,10 @@
-require 'backburner'
+# frozen_string_literal: true
+
+require "backburner"
 
 Backburner::Worker.class_eval do
   class << self; alias_method :original_enqueue, :enqueue; end
-  def self.enqueue(job_class, args=[], opts={})
+  def self.enqueue(job_class, args = [], opts = {})
     job_class.perform(*args)
   end
-end
\ No newline at end of file
+end
diff --git a/activejob/test/support/delayed_job/delayed/backend/test.rb b/activejob/test/support/delayed_job/delayed/backend/test.rb
index f80ec3a5a6..1691896b7c 100644
--- a/activejob/test/support/delayed_job/delayed/backend/test.rb
+++ b/activejob/test/support/delayed_job/delayed/backend/test.rb
@@ -1,5 +1,7 @@
-#copied from https://github.com/collectiveidea/delayed_job/blob/master/spec/delayed/backend/test.rb
-require 'ostruct'
+# frozen_string_literal: true
+
+# copied from https://github.com/collectiveidea/delayed_job/blob/master/spec/delayed/backend/test.rb
+require "ostruct"
 
 # An in-memory backend suitable only for testing. Tries to behave as if it were an ORM.
 module Delayed
@@ -19,14 +21,13 @@ module Delayed
 
         include Delayed::Backend::Base
 
-        cattr_accessor :id
-        self.id = 0
+        cattr_accessor :id, default: 0
 
         def initialize(hash = {})
           self.attempts = 0
           self.priority = 0
           self.id = (self.class.id += 1)
-          hash.each{|k,v| send(:"#{k}=", v)}
+          hash.each { |k, v| send(:"#{k}=", v) }
         end
 
         @jobs = []
@@ -49,7 +50,7 @@ module Delayed
         def self.create!(*args); create(*args); end
 
         def self.clear_locks!(worker_name)
-          all.select{|j| j.locked_by == worker_name}.each {|j| j.locked_by = nil; j.locked_at = nil}
+          all.select { |j| j.locked_by == worker_name }.each { |j| j.locked_by = nil; j.locked_at = nil }
         end
 
         # Find a few candidate jobs to run (in case some immediately get locked by others).
@@ -60,10 +61,10 @@ module Delayed
             !j.failed?
           end
 
-          jobs = jobs.select{|j| Worker.queues.include?(j.queue)}   if Worker.queues.any?
-          jobs = jobs.select{|j| j.priority >= Worker.min_priority} if Worker.min_priority
-          jobs = jobs.select{|j| j.priority <= Worker.max_priority} if Worker.max_priority
-          jobs.sort_by{|j| [j.priority, j.run_at]}[0..limit-1]
+          jobs = jobs.select { |j| Worker.queues.include?(j.queue) }   if Worker.queues.any?
+          jobs = jobs.select { |j| j.priority >= Worker.min_priority } if Worker.min_priority
+          jobs = jobs.select { |j| j.priority <= Worker.max_priority } if Worker.max_priority
+          jobs.sort_by { |j| [j.priority, j.run_at] }[0..limit - 1]
         end
 
         # Lock this job for this worker.
@@ -76,7 +77,7 @@ module Delayed
             self.locked_by = worker
           end
 
-          return true
+          true
         end
 
         def self.db_time_now
@@ -84,7 +85,7 @@ module Delayed
         end
 
         def update_attributes(attrs = {})
-          attrs.each{|k,v| send(:"#{k}=", v)}
+          attrs.each { |k, v| send(:"#{k}=", v) }
           save
         end
 
diff --git a/activejob/test/support/integration/adapters/async.rb b/activejob/test/support/integration/adapters/async.rb
index 44ab98437a..ba9674d7a1 100644
--- a/activejob/test/support/integration/adapters/async.rb
+++ b/activejob/test/support/integration/adapters/async.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module AsyncJobsManager
   def setup
     ActiveJob::Base.queue_adapter = :async
diff --git a/activejob/test/support/integration/adapters/backburner.rb b/activejob/test/support/integration/adapters/backburner.rb
index 2e82562948..eb179011d9 100644
--- a/activejob/test/support/integration/adapters/backburner.rb
+++ b/activejob/test/support/integration/adapters/backburner.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module BackburnerJobsManager
   def setup
     ActiveJob::Base.queue_adapter = :backburner
@@ -23,16 +25,15 @@ module BackburnerJobsManager
   end
 
   def tube
-    @tube ||= Beaneater::Tube.new(Backburner::Worker.connection, "backburner.worker.queue.integration-tests") # backburner dasherizes the queue name
+    @tube ||= Beaneater::Tube.new(@worker.connection, "backburner.worker.queue.integration-tests") # backburner dasherizes the queue name
   end
 
   def can_run?
     begin
-      Backburner::Worker.connection.send :connect!
+      @worker = Backburner::Worker.new
     rescue
       return false
     end
     true
   end
 end
-
diff --git a/activejob/test/support/integration/adapters/delayed_job.rb b/activejob/test/support/integration/adapters/delayed_job.rb
index 0b591964bc..fc9bae47fa 100644
--- a/activejob/test/support/integration/adapters/delayed_job.rb
+++ b/activejob/test/support/integration/adapters/delayed_job.rb
@@ -1,5 +1,7 @@
-require 'delayed_job'
-require 'delayed_job_active_record'
+# frozen_string_literal: true
+
+require "delayed_job"
+require "delayed_job_active_record"
 
 module DelayedJobJobsManager
   def setup
@@ -16,5 +18,6 @@ module DelayedJobJobsManager
 
   def stop_workers
     @worker.stop
+    @thread.join
   end
 end
diff --git a/activejob/test/support/integration/adapters/inline.rb b/activejob/test/support/integration/adapters/inline.rb
index 83c38f706f..10a97fb941 100644
--- a/activejob/test/support/integration/adapters/inline.rb
+++ b/activejob/test/support/integration/adapters/inline.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module InlineJobsManager
   def setup
     ActiveJob::Base.queue_adapter = :inline
@@ -12,4 +14,3 @@ module InlineJobsManager
   def stop_workers
   end
 end
-
diff --git a/activejob/test/support/integration/adapters/qu.rb b/activejob/test/support/integration/adapters/qu.rb
index 256ddb3cf3..67db03e279 100644
--- a/activejob/test/support/integration/adapters/qu.rb
+++ b/activejob/test/support/integration/adapters/qu.rb
@@ -1,9 +1,11 @@
+# frozen_string_literal: true
+
 module QuJobsManager
   def setup
-    require 'qu-rails'
-    require 'qu-redis'
+    require "qu-rails"
+    require "qu-redis"
     ActiveJob::Base.queue_adapter = :qu
-    ENV['REDISTOGO_URL'] = "redis://127.0.0.1:6379/12"
+    ENV["REDISTOGO_URL"] = "redis://127.0.0.1:6379/12"
     backend = Qu::Backend::Redis.new
     backend.namespace = "active_jobs_int_test"
     Qu.backend  = backend
diff --git a/activejob/test/support/integration/adapters/que.rb b/activejob/test/support/integration/adapters/que.rb
index 0cd8952a28..2a771b08c7 100644
--- a/activejob/test/support/integration/adapters/que.rb
+++ b/activejob/test/support/integration/adapters/que.rb
@@ -1,6 +1,8 @@
+# frozen_string_literal: true
+
 module QueJobsManager
   def setup
-    require 'sequel'
+    require "sequel"
     ActiveJob::Base.queue_adapter = :que
     Que.mode = :off
     Que.worker_count = 1
@@ -11,9 +13,9 @@ module QueJobsManager
   end
 
   def start_workers
-    que_url = ENV['QUE_DATABASE_URL'] || 'postgres:///active_jobs_que_int_test'
+    que_url = ENV["QUE_DATABASE_URL"] || "postgres:///active_jobs_que_int_test"
     uri = URI.parse(que_url)
-    user = uri.user||ENV['USER']
+    user = uri.user || ENV["USER"]
     pass = uri.password
     db   = uri.path[1..-1]
     %x{#{"PGPASSWORD=\"#{pass}\"" if pass} psql -c 'drop database if exists "#{db}"' -U #{user} -t template1}
diff --git a/activejob/test/support/integration/adapters/queue_classic.rb b/activejob/test/support/integration/adapters/queue_classic.rb
index 29c04bf625..1b0685a971 100644
--- a/activejob/test/support/integration/adapters/queue_classic.rb
+++ b/activejob/test/support/integration/adapters/queue_classic.rb
@@ -1,8 +1,10 @@
+# frozen_string_literal: true
+
 module QueueClassicJobsManager
   def setup
-    ENV['QC_DATABASE_URL'] ||= 'postgres:///active_jobs_qc_int_test'
-    ENV['QC_RAILS_DATABASE'] = 'false'
-    ENV['QC_LISTEN_TIME']    = "0.5"
+    ENV["QC_DATABASE_URL"] ||= "postgres:///active_jobs_qc_int_test"
+    ENV["QC_RAILS_DATABASE"] = "false"
+    ENV["QC_LISTEN_TIME"]    = "0.5"
     ActiveJob::Base.queue_adapter = :queue_classic
   end
 
@@ -11,8 +13,8 @@ module QueueClassicJobsManager
   end
 
   def start_workers
-    uri = URI.parse(ENV['QC_DATABASE_URL'])
-    user = uri.user||ENV['USER']
+    uri = URI.parse(ENV["QC_DATABASE_URL"])
+    user = uri.user || ENV["USER"]
     pass = uri.password
     db   = uri.path[1..-1]
     %x{#{"PGPASSWORD=\"#{pass}\"" if pass} psql -c 'drop database if exists "#{db}"' -U #{user} -t template1}
@@ -22,7 +24,7 @@ module QueueClassicJobsManager
     QC.default_conn_adapter.disconnect
     QC.default_conn_adapter = nil
     @pid = fork do
-      worker = QC::Worker.new(q_name: 'integration_tests')
+      worker = QC::Worker.new(q_name: "integration_tests")
       worker.start
     end
 
@@ -32,6 +34,6 @@ module QueueClassicJobsManager
   end
 
   def stop_workers
-    Process.kill 'HUP', @pid
+    Process.kill "HUP", @pid
   end
 end
diff --git a/activejob/test/support/integration/adapters/resque.rb b/activejob/test/support/integration/adapters/resque.rb
index 912f4bc387..2ed8302277 100644
--- a/activejob/test/support/integration/adapters/resque.rb
+++ b/activejob/test/support/integration/adapters/resque.rb
@@ -1,11 +1,14 @@
+# frozen_string_literal: true
+
 module ResqueJobsManager
   def setup
     ActiveJob::Base.queue_adapter = :resque
-    Resque.redis = Redis::Namespace.new 'active_jobs_int_test', redis: Redis.connect(url: "redis://127.0.0.1:6379/12", :thread_safe => true)
+    Resque.redis = Redis::Namespace.new "active_jobs_int_test", redis: Redis.new(url: "redis://127.0.0.1:6379/12", thread_safe: true)
     Resque.logger = Rails.logger
     unless can_run?
       puts "Cannot run integration tests for resque. To be able to run integration tests for resque you need to install and start redis.\n"
-      exit
+      status = ENV["CI"] ? false : true
+      exit status
     end
   end
 
@@ -39,11 +42,8 @@ module ResqueJobsManager
   end
 
   def can_run?
-    begin
-      Resque.redis.client.connect
-    rescue
-      return false
-    end
-    true
+    Resque.redis.ping == "PONG"
+  rescue
+    false
   end
 end
diff --git a/activejob/test/support/integration/adapters/sidekiq.rb b/activejob/test/support/integration/adapters/sidekiq.rb
index 2f19d7dacc..c79de12eaf 100644
--- a/activejob/test/support/integration/adapters/sidekiq.rb
+++ b/activejob/test/support/integration/adapters/sidekiq.rb
@@ -1,15 +1,17 @@
-require 'sidekiq/api'
+# frozen_string_literal: true
 
-require 'sidekiq/testing'
+require "sidekiq/api"
+
+require "sidekiq/testing"
 Sidekiq::Testing.disable!
 
 module SidekiqJobsManager
-
   def setup
     ActiveJob::Base.queue_adapter = :sidekiq
     unless can_run?
       puts "Cannot run integration tests for sidekiq. To be able to run integration tests for sidekiq you need to install and start redis.\n"
-      exit
+      status = ENV["CI"] ? false : true
+      exit status
     end
   end
 
@@ -29,7 +31,7 @@ module SidekiqJobsManager
       # Sidekiq is not warning-clean :(
       $VERBOSE = false
 
-      $stdin.reopen('/dev/null')
+      $stdin.reopen(File::NULL)
       $stdout.sync = true
       $stderr.sync = true
 
@@ -49,12 +51,12 @@ module SidekiqJobsManager
         self_write.puts("TERM")
       end
 
-      require 'sidekiq/launcher'
-      sidekiq = Sidekiq::Launcher.new({queues: ["integration_tests"],
+      require "sidekiq/cli"
+      require "sidekiq/launcher"
+      sidekiq = Sidekiq::Launcher.new(queues: ["integration_tests"],
                                        environment: "test",
                                        concurrency: 1,
-                                       timeout: 1,
-                                      })
+                                       timeout: 1)
       Sidekiq.average_scheduled_poll_interval = 0.5
       Sidekiq.options[:poll_interval_average] = 1
       begin
@@ -79,7 +81,7 @@ module SidekiqJobsManager
 
   def stop_workers
     if @pid
-      Process.kill 'TERM', @pid
+      Process.kill "TERM", @pid
       Process.wait @pid
     end
   end
diff --git a/activejob/test/support/integration/adapters/sneakers.rb b/activejob/test/support/integration/adapters/sneakers.rb
index 875803a2d8..965e6e2e6c 100644
--- a/activejob/test/support/integration/adapters/sneakers.rb
+++ b/activejob/test/support/integration/adapters/sneakers.rb
@@ -1,6 +1,8 @@
-require 'sneakers/runner'
-require 'sneakers/publisher'
-require 'timeout'
+# frozen_string_literal: true
+
+require "sneakers/runner"
+require "sneakers/publisher"
+require "timeout"
 
 module Sneakers
   class Publisher
@@ -12,20 +14,19 @@ module Sneakers
   end
 end
 
-
 module SneakersJobsManager
   def setup
     ActiveJob::Base.queue_adapter = :sneakers
-    Sneakers.configure  :heartbeat => 2,
-                        :amqp => 'amqp://guest:guest@localhost:5672',
-                        :vhost => '/',
-                        :exchange => 'active_jobs_sneakers_int_test',
-                        :exchange_type => :direct,
-                        :daemonize => true,
-                        :threads => 1,
-                        :workers => 1,
-                        :pid_path => Rails.root.join("tmp/sneakers.pid").to_s,
-                        :log => Rails.root.join("log/sneakers.log").to_s
+    Sneakers.configure  heartbeat: 2,
+                        amqp: "amqp://guest:guest@localhost:5672",
+                        vhost: "/",
+                        exchange: "active_jobs_sneakers_int_test",
+                        exchange_type: :direct,
+                        daemonize: true,
+                        threads: 1,
+                        workers: 1,
+                        pid_path: Rails.root.join("tmp/sneakers.pid").to_s,
+                        log: Rails.root.join("log/sneakers.log").to_s
     unless can_run?
       puts "Cannot run integration tests for sneakers. To be able to run integration tests for sneakers you need to install and start rabbitmq.\n"
       exit
@@ -40,7 +41,7 @@ module SneakersJobsManager
     @pid = fork do
       queues = %w(integration_tests)
       workers = queues.map do |q|
-        worker_klass = "ActiveJobWorker"+Digest::MD5.hexdigest(q)
+        worker_klass = "ActiveJobWorker" + Digest::MD5.hexdigest(q)
         Sneakers.const_set(worker_klass, Class.new(ActiveJob::QueueAdapters::SneakersAdapter::JobWrapper) do
           from_queue q
         end)
@@ -60,8 +61,8 @@ module SneakersJobsManager
   end
 
   def stop_workers
-    Process.kill 'TERM', @pid
-    Process.kill 'TERM', File.open(Rails.root.join("tmp/sneakers.pid").to_s).read.to_i
+    Process.kill "TERM", @pid
+    Process.kill "TERM", File.open(Rails.root.join("tmp/sneakers.pid").to_s).read.to_i
   rescue
   end
 
@@ -74,7 +75,7 @@ module SneakersJobsManager
     true
   end
 
-  protected
+  private
     def bunny_publisher
       @bunny_publisher ||= begin
         p = ActiveJob::QueueAdapters::SneakersAdapter::JobWrapper.send(:publisher)
@@ -86,5 +87,4 @@ module SneakersJobsManager
     def bunny_queue
       @queue ||= bunny_publisher.exchange.channel.queue "integration_tests", durable: true
     end
-
 end
diff --git a/activejob/test/support/integration/adapters/sucker_punch.rb b/activejob/test/support/integration/adapters/sucker_punch.rb
index 9c0d66b469..099d412c8f 100644
--- a/activejob/test/support/integration/adapters/sucker_punch.rb
+++ b/activejob/test/support/integration/adapters/sucker_punch.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module SuckerPunchJobsManager
   def setup
     ActiveJob::Base.queue_adapter = :sucker_punch
diff --git a/activejob/test/support/integration/dummy_app_template.rb b/activejob/test/support/integration/dummy_app_template.rb
index a0ef38b0b2..7ea78c3350 100644
--- a/activejob/test/support/integration/dummy_app_template.rb
+++ b/activejob/test/support/integration/dummy_app_template.rb
@@ -1,29 +1,30 @@
-if ENV['AJ_ADAPTER'] == 'delayed_job'
+# frozen_string_literal: true
+
+if ENV["AJ_ADAPTER"] == "delayed_job"
   generate "delayed_job:active_record", "--quiet"
 end
 
-rails_command("db:migrate")
-
-initializer 'activejob.rb', <<-CODE
-require "#{File.expand_path("../jobs_manager.rb",  __FILE__)}"
+initializer "activejob.rb", <<-CODE
+require "#{File.expand_path("jobs_manager.rb",  __dir__)}"
 JobsManager.current_manager.setup
 CODE
 
-initializer 'i18n.rb', <<-CODE
+initializer "i18n.rb", <<-CODE
 I18n.available_locales = [:en, :de]
 CODE
 
-file 'app/jobs/test_job.rb', <<-CODE
+file "app/jobs/test_job.rb", <<-CODE
 class TestJob < ActiveJob::Base
   queue_as :integration_tests
 
   def perform(x)
-    File.open(Rails.root.join("tmp/\#{x}"), "wb+") do |f|
+    File.open(Rails.root.join("tmp/\#{x}.new"), "wb+") do |f|
       f.write Marshal.dump({
         "locale" => I18n.locale.to_s || "en",
         "executed_at" => Time.now.to_r
       })
     end
+    File.rename(Rails.root.join("tmp/\#{x}.new"), Rails.root.join("tmp/\#{x}"))
   end
 end
 CODE
diff --git a/activejob/test/support/integration/helper.rb b/activejob/test/support/integration/helper.rb
index 4a1b0bfbcb..a02d874e2e 100644
--- a/activejob/test/support/integration/helper.rb
+++ b/activejob/test/support/integration/helper.rb
@@ -1,12 +1,15 @@
+# frozen_string_literal: true
+
 puts "\n\n*** rake aj:integration:#{ENV['AJ_ADAPTER']} ***\n"
 
 ENV["RAILS_ENV"] = "test"
 ActiveJob::Base.queue_name_prefix = nil
 
-require 'rails/generators/rails/app/app_generator'
+require "rails/generators/rails/app/app_generator"
 
+require "tmpdir"
 dummy_app_path     = Dir.mktmpdir + "/dummy"
-dummy_app_template = File.expand_path("../dummy_app_template.rb",  __FILE__)
+dummy_app_template = File.expand_path("dummy_app_template.rb",  __dir__)
 args = Rails::Generators::ARGVScrubber.new(["new", dummy_app_path, "--skip-gemfile", "--skip-bundle",
   "--skip-git", "--skip-spring", "-d", "sqlite3", "--skip-javascript", "--force", "--quiet",
   "--template", dummy_app_template]).prepare!
@@ -14,12 +17,13 @@ Rails::Generators::AppGenerator.start args
 
 require "#{dummy_app_path}/config/environment.rb"
 
-ActiveRecord::Migrator.migrations_paths = [ Rails.root.join('db/migrate').to_s ]
-require 'rails/test_help'
+ActiveRecord::Migrator.migrations_paths = [ Rails.root.join("db/migrate").to_s ]
+ActiveRecord::Tasks::DatabaseTasks.migrate
+require "rails/test_help"
 
 Rails.backtrace_cleaner.remove_silencers!
 
-require_relative 'test_case_helpers'
+require_relative "test_case_helpers"
 ActiveSupport::TestCase.include(TestCaseHelpers)
 
 JobsManager.current_manager.start_workers
diff --git a/activejob/test/support/integration/jobs_manager.rb b/activejob/test/support/integration/jobs_manager.rb
index 78d48e8d9a..4775f52b2f 100644
--- a/activejob/test/support/integration/jobs_manager.rb
+++ b/activejob/test/support/integration/jobs_manager.rb
@@ -1,9 +1,11 @@
+# frozen_string_literal: true
+
 class JobsManager
   @@managers = {}
   attr :adapter_name
 
   def self.current_manager
-    @@managers[ENV['AJ_ADAPTER']] ||= new(ENV['AJ_ADAPTER'])
+    @@managers[ENV["AJ_ADAPTER"]] ||= new(ENV["AJ_ADAPTER"])
   end
 
   def initialize(adapter_name)
diff --git a/activejob/test/support/integration/test_case_helpers.rb b/activejob/test/support/integration/test_case_helpers.rb
index fdf25c67a1..f02a32a38e 100644
--- a/activejob/test/support/integration/test_case_helpers.rb
+++ b/activejob/test/support/integration/test_case_helpers.rb
@@ -1,6 +1,6 @@
-require 'active_support/concern'
-require 'active_support/core_ext/string/inflections'
-require 'support/integration/jobs_manager'
+# frozen_string_literal: true
+
+require "support/integration/jobs_manager"
 
 module TestCaseHelpers
   extend ActiveSupport::Concern
@@ -18,7 +18,7 @@ module TestCaseHelpers
     end
   end
 
-  protected
+  private
 
     def jobs_manager
       JobsManager.current_manager
@@ -29,11 +29,10 @@ module TestCaseHelpers
     end
 
     def adapter_is?(*adapter_class_symbols)
-      adapter = ActiveJob::Base.queue_adapter.class.name.demodulize.chomp('Adapter').underscore
-      adapter_class_symbols.map(&:to_s).include? adapter
+      adapter_class_symbols.map(&:to_s).include? ActiveJob::Base.queue_adapter_name
     end
 
-    def wait_for_jobs_to_finish_for(seconds=60)
+    def wait_for_jobs_to_finish_for(seconds = 60)
       begin
         Timeout.timeout(seconds) do
           while !job_executed do
@@ -48,7 +47,7 @@ module TestCaseHelpers
       Dummy::Application.root.join("tmp/#{id}")
     end
 
-    def job_executed(id=@id)
+    def job_executed(id = @id)
       job_file(id).exist?
     end
 
@@ -56,11 +55,11 @@ module TestCaseHelpers
       Marshal.load(File.binread(job_file(id)))
     end
 
-    def job_executed_at(id=@id)
+    def job_executed_at(id = @id)
       job_data(id)["executed_at"]
     end
 
-    def job_executed_in_locale(id=@id)
+    def job_executed_in_locale(id = @id)
       job_data(id)["locale"]
     end
 end
diff --git a/activejob/test/support/job_buffer.rb b/activejob/test/support/job_buffer.rb
index 620cb5288d..45a6437685 100644
--- a/activejob/test/support/job_buffer.rb
+++ b/activejob/test/support/job_buffer.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module JobBuffer
   class << self
     def clear
diff --git a/activejob/test/support/que/inline.rb b/activejob/test/support/que/inline.rb
index 0950e52d28..4ca65c1cd4 100644
--- a/activejob/test/support/que/inline.rb
+++ b/activejob/test/support/que/inline.rb
@@ -1,4 +1,6 @@
-require 'que'
+# frozen_string_literal: true
+
+require "que"
 
 Que::Job.class_eval do
   class << self; alias_method :original_enqueue, :enqueue; end
@@ -9,6 +11,6 @@ Que::Job.class_eval do
       options.delete(:priority)
       args << options unless options.empty?
     end
-    self.run(*args)
+    run(*args)
   end
 end
diff --git a/activejob/test/support/queue_classic/inline.rb b/activejob/test/support/queue_classic/inline.rb
index 5743d5bbb5..ca3cd4581b 100644
--- a/activejob/test/support/queue_classic/inline.rb
+++ b/activejob/test/support/queue_classic/inline.rb
@@ -1,21 +1,23 @@
-require 'queue_classic'
+# frozen_string_literal: true
+
+require "queue_classic"
 
 module QC
   class Queue
     def enqueue(method, *args)
-      receiver_str, _, message = method.rpartition('.')
+      receiver_str, _, message = method.rpartition(".")
       receiver = eval(receiver_str)
       receiver.send(message, *args)
     end
 
     def enqueue_in(seconds, method, *args)
-      receiver_str, _, message = method.rpartition('.')
+      receiver_str, _, message = method.rpartition(".")
       receiver = eval(receiver_str)
       receiver.send(message, *args)
     end
 
     def enqueue_at(not_before, method, *args)
-      receiver_str, _, message = method.rpartition('.')
+      receiver_str, _, message = method.rpartition(".")
       receiver = eval(receiver_str)
       receiver.send(message, *args)
     end
diff --git a/activejob/test/support/sneakers/inline.rb b/activejob/test/support/sneakers/inline.rb
index 16d9b830fa..92b69ee3bc 100644
--- a/activejob/test/support/sneakers/inline.rb
+++ b/activejob/test/support/sneakers/inline.rb
@@ -1,10 +1,12 @@
-require 'sneakers'
+# frozen_string_literal: true
+
+require "sneakers"
 
 module Sneakers
   module Worker
     module ClassMethods
       def enqueue(msg)
-        worker = self.new(nil, nil, {})
+        worker = new(nil, nil, {})
         worker.work(*msg)
       end
     end
diff --git a/activemodel/CHANGELOG.md b/activemodel/CHANGELOG.md
index 206699c036..b67a803b9d 100644
--- a/activemodel/CHANGELOG.md
+++ b/activemodel/CHANGELOG.md
@@ -1,2 +1,60 @@
+*   Fix to working before/after validation callbacks on multiple contexts.
 
-Please check [5-0-stable](https://github.com/rails/rails/blob/5-0-stable/activemodel/CHANGELOG.md) for previous changes.
+    *Yoshiyuki Hirano*
+
+## Rails 5.2.0.beta2 (November 28, 2017) ##
+
+*   No changes.
+
+
+## Rails 5.2.0.beta1 (November 27, 2017) ##
+
+*   Execute `ConfirmationValidator` validation when `_confirmation`'s value is `false`.
+
+    *bogdanvlviv*
+
+*   Allow passing a Proc or Symbol to length validator options.
+
+    *Matt Rohrer*
+
+*   Add method `#merge!` for `ActiveModel::Errors`.
+
+    *Jahfer Husain*
+
+*   Fix regression in numericality validator when comparing Decimal and Float input
+    values with more scale than the schema.
+
+    *Bradley Priest*
+
+*   Fix methods `#keys`, `#values` in `ActiveModel::Errors`.
+
+    Change `#keys` to only return the keys that don't have empty messages.
+
+    Change `#values` to only return the not empty values.
+
+    Example:
+
+        # Before
+        person = Person.new
+        person.errors.keys     # => []
+        person.errors.values   # => []
+        person.errors.messages # => {}
+        person.errors[:name]   # => []
+        person.errors.messages # => {:name => []}
+        person.errors.keys     # => [:name]
+        person.errors.values   # => [[]]
+
+        # After
+        person = Person.new
+        person.errors.keys     # => []
+        person.errors.values   # => []
+        person.errors.messages # => {}
+        person.errors[:name]   # => []
+        person.errors.messages # => {:name => []}
+        person.errors.keys     # => []
+        person.errors.values   # => []
+
+    *bogdanvlviv*
+
+
+Please check [5-1-stable](https://github.com/rails/rails/blob/5-1-stable/activemodel/CHANGELOG.md) for previous changes.
diff --git a/activemodel/MIT-LICENSE b/activemodel/MIT-LICENSE
index 8573eb1225..1cb3add0fc 100644
--- a/activemodel/MIT-LICENSE
+++ b/activemodel/MIT-LICENSE
@@ -1,4 +1,4 @@
-Copyright (c) 2004-2016 David Heinemeier Hansson
+Copyright (c) 2004-2018 David Heinemeier Hansson
 
 Permission is hereby granted, free of charge, to any person obtaining
 a copy of this software and associated documentation files (the
diff --git a/activemodel/README.rdoc b/activemodel/README.rdoc
index 77f5761993..1aaf4813ea 100644
--- a/activemodel/README.rdoc
+++ b/activemodel/README.rdoc
@@ -246,16 +246,16 @@ Source code can be downloaded as part of the Rails project on GitHub
 
 Active Model is released under the MIT license:
 
-* http://www.opensource.org/licenses/MIT
+* https://opensource.org/licenses/MIT
 
 
 == Support
 
-API documentation is at
+API documentation is at:
 
 * http://api.rubyonrails.org
 
-Bug reports can be filed for the Ruby on Rails project here:
+Bug reports for the Ruby on Rails project can be filed here:
 
 * https://github.com/rails/rails/issues
 
diff --git a/activemodel/Rakefile b/activemodel/Rakefile
index 036815a987..d39f50a962 100644
--- a/activemodel/Rakefile
+++ b/activemodel/Rakefile
@@ -1,14 +1,14 @@
-require 'rake/testtask'
+# frozen_string_literal: true
 
-dir = File.dirname(__FILE__)
+require "rake/testtask"
 
-task :default => :test
+task default: :test
 
 task :package
 
 Rake::TestTask.new do |t|
   t.libs << "test"
-  t.test_files = Dir.glob("#{dir}/test/cases/**/*_test.rb")
+  t.test_files = Dir.glob("#{__dir__}/test/cases/**/*_test.rb")
   t.warning = true
   t.verbose = true
   t.ruby_opts = ["--dev"] if defined?(JRUBY_VERSION)
@@ -16,8 +16,8 @@ end
 
 namespace :test do
   task :isolated do
-    Dir.glob("#{dir}/test/**/*_test.rb").all? do |file|
-      sh(Gem.ruby, '-w', "-I#{dir}/lib", "-I#{dir}/test", file)
-    end or raise "Failures"
+    Dir.glob("#{__dir__}/test/**/*_test.rb").all? do |file|
+      sh(Gem.ruby, "-w", "-I#{__dir__}/lib", "-I#{__dir__}/test", file)
+    end || raise("Failures")
   end
 end
diff --git a/activemodel/activemodel.gemspec b/activemodel/activemodel.gemspec
index 1c3997b864..a070a2898c 100644
--- a/activemodel/activemodel.gemspec
+++ b/activemodel/activemodel.gemspec
@@ -1,22 +1,29 @@
-version = File.read(File.expand_path('../../RAILS_VERSION', __FILE__)).strip
+# frozen_string_literal: true
+
+version = File.read(File.expand_path("../RAILS_VERSION", __dir__)).strip
 
 Gem::Specification.new do |s|
   s.platform    = Gem::Platform::RUBY
-  s.name        = 'activemodel'
+  s.name        = "activemodel"
   s.version     = version
-  s.summary     = 'A toolkit for building modeling frameworks (part of Rails).'
-  s.description = 'A toolkit for building modeling frameworks like Active Record. Rich support for attributes, callbacks, validations, serialization, internationalization, and testing.'
+  s.summary     = "A toolkit for building modeling frameworks (part of Rails)."
+  s.description = "A toolkit for building modeling frameworks like Active Record. Rich support for attributes, callbacks, validations, serialization, internationalization, and testing."
+
+  s.required_ruby_version = ">= 2.2.2"
 
-  s.required_ruby_version = '>= 2.2.2'
+  s.license = "MIT"
 
-  s.license = 'MIT'
+  s.author   = "David Heinemeier Hansson"
+  s.email    = "david@loudthinking.com"
+  s.homepage = "http://rubyonrails.org"
 
-  s.author   = 'David Heinemeier Hansson'
-  s.email    = 'david@loudthinking.com'
-  s.homepage = 'http://rubyonrails.org'
+  s.files        = Dir["CHANGELOG.md", "MIT-LICENSE", "README.rdoc", "lib/**/*"]
+  s.require_path = "lib"
 
-  s.files        = Dir['CHANGELOG.md', 'MIT-LICENSE', 'README.rdoc', 'lib/**/*']
-  s.require_path = 'lib'
+  s.metadata = {
+    "source_code_uri" => "https://github.com/rails/rails/tree/v#{version}/activemodel",
+    "changelog_uri"   => "https://github.com/rails/rails/blob/v#{version}/activemodel/CHANGELOG.md"
+  }
 
-  s.add_dependency 'activesupport', version
+  s.add_dependency "activesupport", version
 end
diff --git a/activemodel/bin/test b/activemodel/bin/test
index 404cabba51..c53377cc97 100755
--- a/activemodel/bin/test
+++ b/activemodel/bin/test
@@ -1,4 +1,5 @@
 #!/usr/bin/env ruby
-COMPONENT_ROOT = File.expand_path("../../", __FILE__)
-require File.expand_path("../tools/test", COMPONENT_ROOT)
-exit Minitest.run(ARGV)
+# frozen_string_literal: true
+
+COMPONENT_ROOT = File.expand_path("..", __dir__)
+require_relative "../../tools/test"
diff --git a/activemodel/lib/active_model.rb b/activemodel/lib/active_model.rb
index 7de259a60d..bc10d6b4b9 100644
--- a/activemodel/lib/active_model.rb
+++ b/activemodel/lib/active_model.rb
@@ -1,5 +1,7 @@
+# frozen_string_literal: true
+
 #--
-# Copyright (c) 2004-2016 David Heinemeier Hansson
+# Copyright (c) 2004-2018 David Heinemeier Hansson
 #
 # Permission is hereby granted, free of charge, to any person obtaining
 # a copy of this software and associated documentation files (the
@@ -21,37 +23,39 @@
 # WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 #++
 
-require 'active_support'
-require 'active_support/rails'
-require 'active_model/version'
+require "active_support"
+require "active_support/rails"
+require "active_model/version"
 
 module ActiveModel
   extend ActiveSupport::Autoload
 
+  autoload :Attribute
+  autoload :Attributes
   autoload :AttributeAssignment
   autoload :AttributeMethods
-  autoload :BlockValidator, 'active_model/validator'
+  autoload :BlockValidator, "active_model/validator"
   autoload :Callbacks
   autoload :Conversion
   autoload :Dirty
-  autoload :EachValidator, 'active_model/validator'
+  autoload :EachValidator, "active_model/validator"
   autoload :ForbiddenAttributesProtection
   autoload :Lint
   autoload :Model
-  autoload :Name, 'active_model/naming'
+  autoload :Name, "active_model/naming"
   autoload :Naming
   autoload :SecurePassword
   autoload :Serialization
-  autoload :TestCase
   autoload :Translation
+  autoload :Type
   autoload :Validations
   autoload :Validator
 
   eager_autoload do
     autoload :Errors
-    autoload :RangeError, 'active_model/errors'
-    autoload :StrictValidationFailed, 'active_model/errors'
-    autoload :UnknownAttributeError, 'active_model/errors'
+    autoload :RangeError, "active_model/errors"
+    autoload :StrictValidationFailed, "active_model/errors"
+    autoload :UnknownAttributeError, "active_model/errors"
   end
 
   module Serializers
@@ -69,5 +73,5 @@ module ActiveModel
 end
 
 ActiveSupport.on_load(:i18n) do
-  I18n.load_path << File.dirname(__FILE__) + '/active_model/locale/en.yml'
+  I18n.load_path << File.expand_path("active_model/locale/en.yml", __dir__)
 end
diff --git a/activerecord/lib/active_record/attribute.rb b/activemodel/lib/active_model/attribute.rb
index 9530f134d0..27f3e38e31 100644
--- a/activerecord/lib/active_record/attribute.rb
+++ b/activemodel/lib/active_model/attribute.rb
@@ -1,4 +1,8 @@
-module ActiveRecord
+# frozen_string_literal: true
+
+require "active_support/core_ext/object/duplicable"
+
+module ActiveModel
   class Attribute # :nodoc:
     class << self
       def from_database(name, value, type)
@@ -65,7 +69,7 @@ module ActiveRecord
 
     def with_value_from_user(value)
       type.assert_valid_value(value)
-      self.class.from_user(name, value, type, self)
+      self.class.from_user(name, value, type, original_attribute || self)
     end
 
     def with_value_from_database(value)
@@ -122,7 +126,7 @@ module ActiveRecord
 
     def encode_with(coder)
       coder["name"] = name
-      coder["value_before_type_cast"] = value_before_type_cast if value_before_type_cast
+      coder["value_before_type_cast"] = value_before_type_cast unless value_before_type_cast.nil?
       coder["type"] = type if type
       coder["original_attribute"] = original_attribute if original_attribute
       coder["value"] = value if defined?(@value)
@@ -130,108 +134,114 @@ module ActiveRecord
 
     protected
 
-    attr_reader :original_attribute
-    alias_method :assigned?, :original_attribute
+      attr_reader :original_attribute
+      alias_method :assigned?, :original_attribute
 
-    def initialize_dup(other)
-      if defined?(@value) && @value.duplicable?
-        @value = @value.dup
+      def original_value_for_database
+        if assigned?
+          original_attribute.original_value_for_database
+        else
+          _original_value_for_database
+        end
       end
-    end
-
-    def changed_from_assignment?
-      assigned? && type.changed?(original_value, value, value_before_type_cast)
-    end
 
-    def original_value_for_database
-      if assigned?
-        original_attribute.original_value_for_database
-      else
-        _original_value_for_database
+    private
+      def initialize_dup(other)
+        if defined?(@value) && @value.duplicable?
+          @value = @value.dup
+        end
       end
-    end
-
-    def _original_value_for_database
-      value_for_database
-    end
 
-    class FromDatabase < Attribute # :nodoc:
-      def type_cast(value)
-        type.deserialize(value)
+      def changed_from_assignment?
+        assigned? && type.changed?(original_value, value, value_before_type_cast)
       end
 
       def _original_value_for_database
-        value_before_type_cast
+        type.serialize(original_value)
       end
-    end
 
-    class FromUser < Attribute # :nodoc:
-      def type_cast(value)
-        type.cast(value)
-      end
+      class FromDatabase < Attribute # :nodoc:
+        def type_cast(value)
+          type.deserialize(value)
+        end
 
-      def came_from_user?
-        true
+        def _original_value_for_database
+          value_before_type_cast
+        end
       end
-    end
 
-    class WithCastValue < Attribute # :nodoc:
-      def type_cast(value)
-        value
-      end
+      class FromUser < Attribute # :nodoc:
+        def type_cast(value)
+          type.cast(value)
+        end
 
-      def changed_in_place_from?(old_value)
-        false
+        def came_from_user?
+          !type.value_constructed_by_mass_assignment?(value_before_type_cast)
+        end
       end
-    end
 
-    class Null < Attribute # :nodoc:
-      def initialize(name)
-        super(name, nil, Type::Value.new)
-      end
+      class WithCastValue < Attribute # :nodoc:
+        def type_cast(value)
+          value
+        end
 
-      def type_cast(*)
-        nil
+        def changed_in_place?
+          false
+        end
       end
 
-      def with_type(type)
-        self.class.with_cast_value(name, nil, type)
-      end
+      class Null < Attribute # :nodoc:
+        def initialize(name)
+          super(name, nil, Type.default_value)
+        end
 
-      def with_value_from_database(value)
-        raise ActiveModel::MissingAttributeError, "can't write unknown attribute `#{name}`"
-      end
-      alias_method :with_value_from_user, :with_value_from_database
-    end
+        def type_cast(*)
+          nil
+        end
 
-    class Uninitialized < Attribute # :nodoc:
-      UNINITIALIZED_ORIGINAL_VALUE = Object.new
+        def with_type(type)
+          self.class.with_cast_value(name, nil, type)
+        end
 
-      def initialize(name, type)
-        super(name, nil, type)
+        def with_value_from_database(value)
+          raise ActiveModel::MissingAttributeError, "can't write unknown attribute `#{name}`"
+        end
+        alias_method :with_value_from_user, :with_value_from_database
       end
 
-      def value
-        if block_given?
-          yield name
+      class Uninitialized < Attribute # :nodoc:
+        UNINITIALIZED_ORIGINAL_VALUE = Object.new
+
+        def initialize(name, type)
+          super(name, nil, type)
         end
-      end
 
-      def original_value
-        UNINITIALIZED_ORIGINAL_VALUE
-      end
+        def value
+          if block_given?
+            yield name
+          end
+        end
 
-      def value_for_database
-      end
+        def original_value
+          UNINITIALIZED_ORIGINAL_VALUE
+        end
 
-      def initialized?
-        false
-      end
+        def value_for_database
+        end
+
+        def initialized?
+          false
+        end
 
-      def with_type(type)
-        self.class.new(name, type)
+        def forgetting_assignment
+          dup
+        end
+
+        def with_type(type)
+          self.class.new(name, type)
+        end
       end
-    end
-    private_constant :FromDatabase, :FromUser, :Null, :Uninitialized, :WithCastValue
+
+      private_constant :FromDatabase, :FromUser, :Null, :Uninitialized, :WithCastValue
   end
 end
diff --git a/activerecord/lib/active_record/attribute/user_provided_default.rb b/activemodel/lib/active_model/attribute/user_provided_default.rb
index 4580813364..f274b687d4 100644
--- a/activerecord/lib/active_record/attribute/user_provided_default.rb
+++ b/activemodel/lib/active_model/attribute/user_provided_default.rb
@@ -1,6 +1,8 @@
-require 'active_record/attribute'
+# frozen_string_literal: true
 
-module ActiveRecord
+require "active_model/attribute"
+
+module ActiveModel
   class Attribute # :nodoc:
     class UserProvidedDefault < FromUser # :nodoc:
       def initialize(name, value, type, database_default)
@@ -22,7 +24,7 @@ module ActiveRecord
 
       protected
 
-      attr_reader :user_provided_value
+        attr_reader :user_provided_value
     end
   end
 end
diff --git a/activemodel/lib/active_model/attribute_assignment.rb b/activemodel/lib/active_model/attribute_assignment.rb
index 62014cd1cd..aa931119ff 100644
--- a/activemodel/lib/active_model/attribute_assignment.rb
+++ b/activemodel/lib/active_model/attribute_assignment.rb
@@ -1,4 +1,6 @@
-require 'active_support/core_ext/hash/keys'
+# frozen_string_literal: true
+
+require "active_support/core_ext/hash/keys"
 
 module ActiveModel
   module AttributeAssignment
@@ -19,15 +21,15 @@ module ActiveModel
     #   cat = Cat.new
     #   cat.assign_attributes(name: "Gorby", status: "yawning")
     #   cat.name # => 'Gorby'
-    #   cat.status => 'yawning'
+    #   cat.status # => 'yawning'
     #   cat.assign_attributes(status: "sleeping")
     #   cat.name # => 'Gorby'
-    #   cat.status => 'sleeping'
+    #   cat.status # => 'sleeping'
     def assign_attributes(new_attributes)
       if !new_attributes.respond_to?(:stringify_keys)
         raise ArgumentError, "When assigning attributes, you must pass a hash as an argument."
       end
-      return if new_attributes.nil? || new_attributes.empty?
+      return if new_attributes.empty?
 
       attributes = new_attributes.stringify_keys
       _assign_attributes(sanitize_for_mass_assignment(attributes))
@@ -35,18 +37,19 @@ module ActiveModel
 
     private
 
-    def _assign_attributes(attributes)
-      attributes.each do |k, v|
-        _assign_attribute(k, v)
+      def _assign_attributes(attributes)
+        attributes.each do |k, v|
+          _assign_attribute(k, v)
+        end
       end
-    end
 
-    def _assign_attribute(k, v)
-      if respond_to?("#{k}=")
-        public_send("#{k}=", v)
-      else
-        raise UnknownAttributeError.new(self, k)
+      def _assign_attribute(k, v)
+        setter = :"#{k}="
+        if respond_to?(setter)
+          public_send(setter, v)
+        else
+          raise UnknownAttributeError.new(self, k)
+        end
       end
-    end
   end
 end
diff --git a/activemodel/lib/active_model/attribute_methods.rb b/activemodel/lib/active_model/attribute_methods.rb
index cc6285f932..888a431e5f 100644
--- a/activemodel/lib/active_model/attribute_methods.rb
+++ b/activemodel/lib/active_model/attribute_methods.rb
@@ -1,5 +1,6 @@
-require 'concurrent/map'
-require 'mutex_m'
+# frozen_string_literal: true
+
+require "concurrent/map"
 
 module ActiveModel
   # Raised when an attribute is not defined.
@@ -68,9 +69,8 @@ module ActiveModel
     CALL_COMPILABLE_REGEXP = /\A[a-zA-Z_]\w*[!?]?\z/
 
     included do
-      class_attribute :attribute_aliases, :attribute_method_matchers, instance_writer: false
-      self.attribute_aliases = {}
-      self.attribute_method_matchers = [ClassMethods::AttributeMethodMatcher.new]
+      class_attribute :attribute_aliases, instance_writer: false, default: {}
+      class_attribute :attribute_method_matchers, instance_writer: false, default: [ ClassMethods::AttributeMethodMatcher.new ]
     end
 
     module ClassMethods
@@ -289,7 +289,7 @@ module ActiveModel
             generate_method = "define_method_#{matcher.method_missing_target}"
 
             if respond_to?(generate_method, true)
-              send(generate_method, attr_name)
+              send(generate_method, attr_name.to_s)
             else
               define_proxy_call true, generated_attribute_methods, method_name, matcher.method_missing_target, attr_name.to_s
             end
@@ -328,18 +328,15 @@ module ActiveModel
         attribute_method_matchers_cache.clear
       end
 
-      def generated_attribute_methods #:nodoc:
-        @generated_attribute_methods ||= Module.new {
-          extend Mutex_m
-        }.tap { |mod| include mod }
-      end
+      private
+        def generated_attribute_methods
+          @generated_attribute_methods ||= Module.new.tap { |mod| include mod }
+        end
 
-      protected
-        def instance_method_already_implemented?(method_name) #:nodoc:
+        def instance_method_already_implemented?(method_name)
           generated_attribute_methods.method_defined?(method_name)
         end
 
-      private
         # The methods +method_missing+ and +respond_to?+ of this module are
         # invoked often in a typical rails, both of which invoke the method
         # +matched_attribute_method+. The latter method iterates through an
@@ -349,11 +346,11 @@ module ActiveModel
         # used to alleviate the GC, which ultimately also speeds up the app
         # significantly (in our case our test suite finishes 10% faster with
         # this cache).
-        def attribute_method_matchers_cache #:nodoc:
+        def attribute_method_matchers_cache
           @attribute_method_matchers_cache ||= Concurrent::Map.new(initial_capacity: 4)
         end
 
-        def attribute_method_matchers_matching(method_name) #:nodoc:
+        def attribute_method_matchers_matching(method_name)
           attribute_method_matchers_cache.compute_if_absent(method_name) do
             # Must try to match prefixes/suffixes first, or else the matcher with no prefix/suffix
             # will match every time.
@@ -365,8 +362,8 @@ module ActiveModel
         # Define a method `name` in `mod` that dispatches to `send`
         # using the given `extra` args. This falls back on `define_method`
         # and `send` if the given names cannot be compiled.
-        def define_proxy_call(include_private, mod, name, send, *extra) #:nodoc:
-          defn = if name =~ NAME_COMPILABLE_REGEXP
+        def define_proxy_call(include_private, mod, name, send, *extra)
+          defn = if NAME_COMPILABLE_REGEXP.match?(name)
             "def #{name}(*args)"
           else
             "define_method(:'#{name}') do |*args|"
@@ -374,7 +371,7 @@ module ActiveModel
 
           extra = (extra.map!(&:inspect) << "*args").join(", ".freeze)
 
-          target = if send =~ CALL_COMPILABLE_REGEXP
+          target = if CALL_COMPILABLE_REGEXP.match?(send)
             "#{"self." unless include_private}#{send}(#{extra})"
           else
             "send(:'#{send}', #{extra})"
@@ -393,7 +390,7 @@ module ActiveModel
           AttributeMethodMatch = Struct.new(:target, :attr_name, :method_name)
 
           def initialize(options = {})
-            @prefix, @suffix = options.fetch(:prefix, ''), options.fetch(:suffix, '')
+            @prefix, @suffix = options.fetch(:prefix, ""), options.fetch(:suffix, "")
             @regex = /^(?:#{Regexp.escape(@prefix)})(.*)(?:#{Regexp.escape(@suffix)})$/
             @method_missing_target = "#{@prefix}attribute#{@suffix}"
             @method_name = "#{prefix}%s#{suffix}"
@@ -458,12 +455,11 @@ module ActiveModel
       end
     end
 
-    protected
-      def attribute_method?(attr_name) #:nodoc:
+    private
+      def attribute_method?(attr_name)
         respond_to_without_attributes?(:attributes) && attributes.include?(attr_name)
       end
 
-    private
       # Returns a struct representing the matching attribute method.
       # The struct's attributes are prefix, base and suffix.
       def matched_attribute_method(method_name)
@@ -474,5 +470,9 @@ module ActiveModel
       def missing_attribute(attr_name, stack)
         raise ActiveModel::MissingAttributeError, "missing attribute: #{attr_name}", stack
       end
+
+      def _read_attribute(attr)
+        __send__(attr)
+      end
   end
 end
diff --git a/activemodel/lib/active_model/attribute_mutation_tracker.rb b/activemodel/lib/active_model/attribute_mutation_tracker.rb
new file mode 100644
index 0000000000..c67e1b809a
--- /dev/null
+++ b/activemodel/lib/active_model/attribute_mutation_tracker.rb
@@ -0,0 +1,116 @@
+# frozen_string_literal: true
+
+require "active_support/core_ext/hash/indifferent_access"
+
+module ActiveModel
+  class AttributeMutationTracker # :nodoc:
+    OPTION_NOT_GIVEN = Object.new
+
+    def initialize(attributes)
+      @attributes = attributes
+      @forced_changes = Set.new
+    end
+
+    def changed_values
+      attr_names.each_with_object({}.with_indifferent_access) do |attr_name, result|
+        if changed?(attr_name)
+          result[attr_name] = attributes[attr_name].original_value
+        end
+      end
+    end
+
+    def changes
+      attr_names.each_with_object({}.with_indifferent_access) do |attr_name, result|
+        change = change_to_attribute(attr_name)
+        if change
+          result[attr_name] = change
+        end
+      end
+    end
+
+    def change_to_attribute(attr_name)
+      attr_name = attr_name.to_s
+      if changed?(attr_name)
+        [attributes[attr_name].original_value, attributes.fetch_value(attr_name)]
+      end
+    end
+
+    def any_changes?
+      attr_names.any? { |attr| changed?(attr) }
+    end
+
+    def changed?(attr_name, from: OPTION_NOT_GIVEN, to: OPTION_NOT_GIVEN)
+      attr_name = attr_name.to_s
+      forced_changes.include?(attr_name) ||
+        attributes[attr_name].changed? &&
+        (OPTION_NOT_GIVEN == from || attributes[attr_name].original_value == from) &&
+        (OPTION_NOT_GIVEN == to || attributes[attr_name].value == to)
+    end
+
+    def changed_in_place?(attr_name)
+      attributes[attr_name.to_s].changed_in_place?
+    end
+
+    def forget_change(attr_name)
+      attr_name = attr_name.to_s
+      attributes[attr_name] = attributes[attr_name].forgetting_assignment
+      forced_changes.delete(attr_name)
+    end
+
+    def original_value(attr_name)
+      attributes[attr_name.to_s].original_value
+    end
+
+    def force_change(attr_name)
+      forced_changes << attr_name.to_s
+    end
+
+    # TODO Change this to private once we've dropped Ruby 2.2 support.
+    # Workaround for Ruby 2.2 "private attribute?" warning.
+    protected
+
+      attr_reader :attributes, :forced_changes
+
+    private
+
+      def attr_names
+        attributes.keys
+      end
+  end
+
+  class NullMutationTracker # :nodoc:
+    include Singleton
+
+    def changed_values(*)
+      {}
+    end
+
+    def changes(*)
+      {}
+    end
+
+    def change_to_attribute(attr_name)
+    end
+
+    def any_changes?(*)
+      false
+    end
+
+    def changed?(*)
+      false
+    end
+
+    def changed_in_place?(*)
+      false
+    end
+
+    def forget_change(*)
+    end
+
+    def original_value(*)
+    end
+
+    def force_change(*)
+    end
+  end
+end
diff --git a/activerecord/lib/active_record/attribute_set.rb b/activemodel/lib/active_model/attribute_set.rb
index 720d5f8b7c..54a5dd4064 100644
--- a/activerecord/lib/active_record/attribute_set.rb
+++ b/activemodel/lib/active_model/attribute_set.rb
@@ -1,9 +1,11 @@
-require 'active_record/attribute_set/builder'
-require 'active_record/attribute_set/yaml_encoder'
+# frozen_string_literal: true
 
-module ActiveRecord
+require "active_model/attribute_set/builder"
+require "active_model/attribute_set/yaml_encoder"
+
+module ActiveModel
   class AttributeSet # :nodoc:
-    delegate :each_value, to: :attributes
+    delegate :each_value, :fetch, :except, to: :attributes
 
     def initialize(attributes)
       @attributes = attributes
@@ -64,7 +66,7 @@ module ActiveRecord
     end
 
     def deep_dup
-      dup.tap do |copy|
+      self.class.allocate.tap do |copy|
         copy.instance_variable_set(:@attributes, attributes.deep_dup)
       end
     end
@@ -100,12 +102,12 @@ module ActiveRecord
 
     protected
 
-    attr_reader :attributes
+      attr_reader :attributes
 
     private
 
-    def initialized_attributes
-      attributes.select { |_, attr| attr.initialized? }
-    end
+      def initialized_attributes
+        attributes.select { |_, attr| attr.initialized? }
+      end
   end
 end
diff --git a/activerecord/lib/active_record/attribute_set/builder.rb b/activemodel/lib/active_model/attribute_set/builder.rb
index 24a255efc1..758eb830fc 100644
--- a/activerecord/lib/active_record/attribute_set/builder.rb
+++ b/activemodel/lib/active_model/attribute_set/builder.rb
@@ -1,35 +1,34 @@
-require 'active_record/attribute'
+# frozen_string_literal: true
 
-module ActiveRecord
+require "active_model/attribute"
+
+module ActiveModel
   class AttributeSet # :nodoc:
     class Builder # :nodoc:
-      attr_reader :types, :always_initialized
+      attr_reader :types, :default_attributes
 
-      def initialize(types, always_initialized = nil)
+      def initialize(types, default_attributes = {})
         @types = types
-        @always_initialized = always_initialized
+        @default_attributes = default_attributes
       end
 
       def build_from_database(values = {}, additional_types = {})
-        if always_initialized && !values.key?(always_initialized)
-          values[always_initialized] = nil
-        end
-
-        attributes = LazyAttributeHash.new(types, values, additional_types)
+        attributes = LazyAttributeHash.new(types, values, additional_types, default_attributes)
         AttributeSet.new(attributes)
       end
     end
   end
 
   class LazyAttributeHash # :nodoc:
-    delegate :transform_values, :each_key, :each_value, to: :materialize
+    delegate :transform_values, :each_key, :each_value, :fetch, :except, to: :materialize
 
-    def initialize(types, values, additional_types)
+    def initialize(types, values, additional_types, default_attributes)
       @types = types
       @values = values
       @additional_types = additional_types
       @materialized = false
       @delegate_hash = {}
+      @default_attributes = default_attributes
     end
 
     def key?(key)
@@ -76,33 +75,50 @@ module ActiveRecord
       end
     end
 
+    def marshal_dump
+      materialize
+    end
+
+    def marshal_load(delegate_hash)
+      @delegate_hash = delegate_hash
+      @types = {}
+      @values = {}
+      @additional_types = {}
+      @materialized = true
+    end
+
     protected
 
-    attr_reader :types, :values, :additional_types, :delegate_hash
+      attr_reader :types, :values, :additional_types, :delegate_hash, :default_attributes
 
-    def materialize
-      unless @materialized
-        values.each_key { |key| self[key] }
-        types.each_key { |key| self[key] }
-        unless frozen?
-          @materialized = true
+      def materialize
+        unless @materialized
+          values.each_key { |key| self[key] }
+          types.each_key { |key| self[key] }
+          unless frozen?
+            @materialized = true
+          end
         end
+        delegate_hash
       end
-      delegate_hash
-    end
 
     private
 
-    def assign_default_value(name)
-      type = additional_types.fetch(name, types[name])
-      value_present = true
-      value = values.fetch(name) { value_present = false }
-
-      if value_present
-        delegate_hash[name] = Attribute.from_database(name, value, type)
-      elsif types.key?(name)
-        delegate_hash[name] = Attribute.uninitialized(name, type)
+      def assign_default_value(name)
+        type = additional_types.fetch(name, types[name])
+        value_present = true
+        value = values.fetch(name) { value_present = false }
+
+        if value_present
+          delegate_hash[name] = Attribute.from_database(name, value, type)
+        elsif types.key?(name)
+          attr = default_attributes[name]
+          if attr
+            delegate_hash[name] = attr.dup
+          else
+            delegate_hash[name] = Attribute.uninitialized(name, type)
+          end
+        end
       end
-    end
   end
 end
diff --git a/activerecord/lib/active_record/attribute_set/yaml_encoder.rb b/activemodel/lib/active_model/attribute_set/yaml_encoder.rb
index 6208048231..4ea945b956 100644
--- a/activerecord/lib/active_record/attribute_set/yaml_encoder.rb
+++ b/activemodel/lib/active_model/attribute_set/yaml_encoder.rb
@@ -1,14 +1,16 @@
-module ActiveRecord
+# frozen_string_literal: true
+
+module ActiveModel
   class AttributeSet
     # Attempts to do more intelligent YAML dumping of an
-    # ActiveRecord::AttributeSet to reduce the size of the resulting string
-    class YAMLEncoder
+    # ActiveModel::AttributeSet to reduce the size of the resulting string
+    class YAMLEncoder # :nodoc:
       def initialize(default_types)
         @default_types = default_types
       end
 
       def encode(attribute_set, coder)
-        coder['concise_attributes'] = attribute_set.each_value.map do |attr|
+        coder["concise_attributes"] = attribute_set.each_value.map do |attr|
           if attr.type.equal?(default_types[attr.name])
             attr.with_type(nil)
           else
@@ -18,10 +20,10 @@ module ActiveRecord
       end
 
       def decode(coder)
-        if coder['attributes']
-          coder['attributes']
+        if coder["attributes"]
+          coder["attributes"]
         else
-          attributes_hash = Hash[coder['concise_attributes'].map do |attr|
+          attributes_hash = Hash[coder["concise_attributes"].map do |attr|
             if attr.type.nil?
               attr = attr.with_type(default_types[attr.name])
             end
@@ -33,7 +35,7 @@ module ActiveRecord
 
       protected
 
-      attr_reader :default_types
+        attr_reader :default_types
     end
   end
 end
diff --git a/activemodel/lib/active_model/attributes.rb b/activemodel/lib/active_model/attributes.rb
new file mode 100644
index 0000000000..cac461b549
--- /dev/null
+++ b/activemodel/lib/active_model/attributes.rb
@@ -0,0 +1,108 @@
+# frozen_string_literal: true
+
+require "active_support/core_ext/object/deep_dup"
+require "active_model/attribute_set"
+require "active_model/attribute/user_provided_default"
+
+module ActiveModel
+  module Attributes #:nodoc:
+    extend ActiveSupport::Concern
+    include ActiveModel::AttributeMethods
+
+    included do
+      attribute_method_suffix "="
+      class_attribute :attribute_types, :_default_attributes, instance_accessor: false
+      self.attribute_types = Hash.new(Type.default_value)
+      self._default_attributes = AttributeSet.new({})
+    end
+
+    module ClassMethods
+      def attribute(name, type = Type::Value.new, **options)
+        name = name.to_s
+        if type.is_a?(Symbol)
+          type = ActiveModel::Type.lookup(type, **options.except(:default))
+        end
+        self.attribute_types = attribute_types.merge(name => type)
+        define_default_attribute(name, options.fetch(:default, NO_DEFAULT_PROVIDED), type)
+        define_attribute_methods(name)
+      end
+
+      private
+
+        def define_method_attribute=(name)
+          safe_name = name.unpack("h*".freeze).first
+          ActiveModel::AttributeMethods::AttrNames.set_name_cache safe_name, name
+
+          generated_attribute_methods.module_eval <<-STR, __FILE__, __LINE__ + 1
+            def __temp__#{safe_name}=(value)
+              name = ::ActiveModel::AttributeMethods::AttrNames::ATTR_#{safe_name}
+              write_attribute(name, value)
+            end
+            alias_method #{(name + '=').inspect}, :__temp__#{safe_name}=
+            undef_method :__temp__#{safe_name}=
+          STR
+        end
+
+        NO_DEFAULT_PROVIDED = Object.new # :nodoc:
+        private_constant :NO_DEFAULT_PROVIDED
+
+        def define_default_attribute(name, value, type)
+          self._default_attributes = _default_attributes.deep_dup
+          if value == NO_DEFAULT_PROVIDED
+            default_attribute = _default_attributes[name].with_type(type)
+          else
+            default_attribute = Attribute::UserProvidedDefault.new(
+              name,
+              value,
+              type,
+              _default_attributes.fetch(name.to_s) { nil },
+            )
+          end
+          _default_attributes[name] = default_attribute
+        end
+    end
+
+    def initialize(*)
+      @attributes = self.class._default_attributes.deep_dup
+      super
+    end
+
+    private
+
+      def write_attribute(attr_name, value)
+        name = if self.class.attribute_alias?(attr_name)
+          self.class.attribute_alias(attr_name).to_s
+        else
+          attr_name.to_s
+        end
+
+        @attributes.write_from_user(name, value)
+        value
+      end
+
+      def attribute(attr_name)
+        name = if self.class.attribute_alias?(attr_name)
+          self.class.attribute_alias(attr_name).to_s
+        else
+          attr_name.to_s
+        end
+        @attributes.fetch_value(name)
+      end
+
+      # Handle *= for method_missing.
+      def attribute=(attribute_name, value)
+        write_attribute(attribute_name, value)
+      end
+  end
+
+  module AttributeMethods #:nodoc:
+    AttrNames = Module.new {
+      def self.set_name_cache(name, value)
+        const_name = "ATTR_#{name}"
+        unless const_defined? const_name
+          const_set const_name, value.dup.freeze
+        end
+      end
+    }
+  end
+end
diff --git a/activemodel/lib/active_model/callbacks.rb b/activemodel/lib/active_model/callbacks.rb
index 0d6a3dc52d..8fa9680cb1 100644
--- a/activemodel/lib/active_model/callbacks.rb
+++ b/activemodel/lib/active_model/callbacks.rb
@@ -1,4 +1,6 @@
-require 'active_support/core_ext/array/extract_options'
+# frozen_string_literal: true
+
+require "active_support/core_ext/array/extract_options"
 
 module ActiveModel
   # == Active \Model \Callbacks
@@ -56,6 +58,9 @@ module ActiveModel
   #
   # Would only create the +after_create+ and +before_create+ callback methods in
   # your class.
+  #
+  # NOTE: Calling the same callback multiple times will overwrite previous callback definitions.
+  #
   module Callbacks
     def self.extended(base) #:nodoc:
       base.class_eval do
@@ -98,12 +103,11 @@ module ActiveModel
     #     end
     #   end
     #
-    # NOTE: +method_name+ passed to `define_model_callbacks` must not end with
-    # `!`, `?` or `=`.
+    # NOTE: +method_name+ passed to define_model_callbacks must not end with
+    # <tt>!</tt>, <tt>?</tt> or <tt>=</tt>.
     def define_model_callbacks(*callbacks)
       options = callbacks.extract_options!
       options = {
-        terminator: deprecated_false_terminator,
         skip_after_callbacks_if_terminated: true,
         scope: [:kind, :name],
         only: [:before, :around, :after]
@@ -122,28 +126,28 @@ module ActiveModel
 
     private
 
-    def _define_before_model_callback(klass, callback) #:nodoc:
-      klass.define_singleton_method("before_#{callback}") do |*args, &block|
-        set_callback(:"#{callback}", :before, *args, &block)
+      def _define_before_model_callback(klass, callback)
+        klass.define_singleton_method("before_#{callback}") do |*args, &block|
+          set_callback(:"#{callback}", :before, *args, &block)
+        end
       end
-    end
 
-    def _define_around_model_callback(klass, callback) #:nodoc:
-      klass.define_singleton_method("around_#{callback}") do |*args, &block|
-        set_callback(:"#{callback}", :around, *args, &block)
+      def _define_around_model_callback(klass, callback)
+        klass.define_singleton_method("around_#{callback}") do |*args, &block|
+          set_callback(:"#{callback}", :around, *args, &block)
+        end
       end
-    end
 
-    def _define_after_model_callback(klass, callback) #:nodoc:
-      klass.define_singleton_method("after_#{callback}") do |*args, &block|
-        options = args.extract_options!
-        options[:prepend] = true
-        conditional = ActiveSupport::Callbacks::Conditionals::Value.new { |v|
-          v != false
-        }
-        options[:if] = Array(options[:if]) << conditional
-        set_callback(:"#{callback}", :after, *(args << options), &block)
+      def _define_after_model_callback(klass, callback)
+        klass.define_singleton_method("after_#{callback}") do |*args, &block|
+          options = args.extract_options!
+          options[:prepend] = true
+          conditional = ActiveSupport::Callbacks::Conditionals::Value.new { |v|
+            v != false
+          }
+          options[:if] = Array(options[:if]) << conditional
+          set_callback(:"#{callback}", :after, *(args << options), &block)
+        end
       end
-    end
   end
 end
diff --git a/activemodel/lib/active_model/conversion.rb b/activemodel/lib/active_model/conversion.rb
index a932ada45c..cdc1282817 100644
--- a/activemodel/lib/active_model/conversion.rb
+++ b/activemodel/lib/active_model/conversion.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActiveModel
   # == Active \Model \Conversion
   #
@@ -46,9 +48,13 @@ module ActiveModel
     #   class Person
     #     include ActiveModel::Conversion
     #     attr_accessor :id
+    #
+    #     def initialize(id)
+    #       @id = id
+    #     end
     #   end
     #
-    #   person = Person.create(id: 1)
+    #   person = Person.new(1)
     #   person.to_key # => [1]
     def to_key
       key = respond_to?(:id) && id
@@ -61,15 +67,20 @@ module ActiveModel
     #   class Person
     #     include ActiveModel::Conversion
     #     attr_accessor :id
+    #
+    #     def initialize(id)
+    #       @id = id
+    #     end
+    #
     #     def persisted?
     #       true
     #     end
     #   end
     #
-    #   person = Person.create(id: 1)
+    #   person = Person.new(1)
     #   person.to_param # => "1"
     def to_param
-      (persisted? && key = to_key) ? key.join('-') : nil
+      (persisted? && key = to_key) ? key.join("-") : nil
     end
 
     # Returns a +string+ identifying the path associated with the object.
diff --git a/activemodel/lib/active_model/dirty.rb b/activemodel/lib/active_model/dirty.rb
index 90047c3c12..d2ebd18107 100644
--- a/activemodel/lib/active_model/dirty.rb
+++ b/activemodel/lib/active_model/dirty.rb
@@ -1,5 +1,8 @@
-require 'active_support/hash_with_indifferent_access'
-require 'active_support/core_ext/object/duplicable'
+# frozen_string_literal: true
+
+require "active_support/hash_with_indifferent_access"
+require "active_support/core_ext/object/duplicable"
+require "active_model/attribute_mutation_tracker"
 
 module ActiveModel
   # == Active \Model \Dirty
@@ -26,8 +29,8 @@ module ActiveModel
   #
   #     define_attribute_methods :name
   #
-  #     def initialize(name)
-  #       @name = name
+  #     def initialize
+  #       @name = nil
   #     end
   #
   #     def name
@@ -58,7 +61,7 @@ module ActiveModel
   #
   # A newly instantiated +Person+ object is unchanged:
   #
-  #   person = Person.new("Uncle Bob")
+  #   person = Person.new
   #   person.changed? # => false
   #
   # Change the name:
@@ -66,11 +69,11 @@ module ActiveModel
   #   person.name = 'Bob'
   #   person.changed?       # => true
   #   person.name_changed?  # => true
-  #   person.name_changed?(from: "Uncle Bob", to: "Bob") # => true
-  #   person.name_was       # => "Uncle Bob"
-  #   person.name_change    # => ["Uncle Bob", "Bob"]
+  #   person.name_changed?(from: nil, to: "Bob") # => true
+  #   person.name_was       # => nil
+  #   person.name_change    # => [nil, "Bob"]
   #   person.name = 'Bill'
-  #   person.name_change    # => ["Uncle Bob", "Bill"]
+  #   person.name_change    # => [nil, "Bill"]
   #
   # Save the changes:
   #
@@ -80,9 +83,9 @@ module ActiveModel
   #
   # Reset the changes:
   #
-  #   person.previous_changes         # => {"name" => ["Uncle Bob", "Bill"]}
+  #   person.previous_changes         # => {"name" => [nil, "Bill"]}
   #   person.name_previously_changed? # => true
-  #   person.name_previous_change     # => ["Uncle Bob", "Bill"]
+  #   person.name_previous_change     # => [nil, "Bill"]
   #   person.reload!
   #   person.previous_changes         # => {}
   #
@@ -123,9 +126,27 @@ module ActiveModel
     private_constant :OPTION_NOT_GIVEN
 
     included do
-      attribute_method_suffix '_changed?', '_change', '_will_change!', '_was'
-      attribute_method_suffix '_previously_changed?', '_previous_change'
-      attribute_method_affix prefix: 'restore_', suffix: '!'
+      attribute_method_suffix "_changed?", "_change", "_will_change!", "_was"
+      attribute_method_suffix "_previously_changed?", "_previous_change"
+      attribute_method_affix prefix: "restore_", suffix: "!"
+    end
+
+    def initialize_dup(other) # :nodoc:
+      super
+      if self.class.respond_to?(:_default_attributes)
+        @attributes = self.class._default_attributes.map do |attr|
+          attr.with_value_from_user(@attributes.fetch_value(attr.name))
+        end
+      end
+      @mutations_from_database = nil
+    end
+
+    def changes_applied # :nodoc:
+      @previously_changed = changes
+      @mutations_before_last_save = mutations_from_database
+      @attributes_changed_by_setter = ActiveSupport::HashWithIndifferentAccess.new
+      forget_attribute_assignments
+      @mutations_from_database = nil
     end
 
     # Returns +true+ if any of the attributes have unsaved changes, +false+ otherwise.
@@ -146,6 +167,60 @@ module ActiveModel
       changed_attributes.keys
     end
 
+    # Handles <tt>*_changed?</tt> for +method_missing+.
+    def attribute_changed?(attr, from: OPTION_NOT_GIVEN, to: OPTION_NOT_GIVEN) # :nodoc:
+      !!changes_include?(attr) &&
+        (to == OPTION_NOT_GIVEN || to == _read_attribute(attr)) &&
+        (from == OPTION_NOT_GIVEN || from == changed_attributes[attr])
+    end
+
+    # Handles <tt>*_was</tt> for +method_missing+.
+    def attribute_was(attr) # :nodoc:
+      attribute_changed?(attr) ? changed_attributes[attr] : _read_attribute(attr)
+    end
+
+    # Handles <tt>*_previously_changed?</tt> for +method_missing+.
+    def attribute_previously_changed?(attr) #:nodoc:
+      previous_changes_include?(attr)
+    end
+
+    # Restore all previous data of the provided attributes.
+    def restore_attributes(attributes = changed)
+      attributes.each { |attr| restore_attribute! attr }
+    end
+
+    # Clears all dirty data: current changes and previous changes.
+    def clear_changes_information
+      @previously_changed = ActiveSupport::HashWithIndifferentAccess.new
+      @mutations_before_last_save = nil
+      @attributes_changed_by_setter = ActiveSupport::HashWithIndifferentAccess.new
+      forget_attribute_assignments
+      @mutations_from_database = nil
+    end
+
+    def clear_attribute_changes(attr_names)
+      attributes_changed_by_setter.except!(*attr_names)
+      attr_names.each do |attr_name|
+        clear_attribute_change(attr_name)
+      end
+    end
+
+    # Returns a hash of the attributes with unsaved changes indicating their original
+    # values like <tt>attr => original value</tt>.
+    #
+    #   person.name # => "bob"
+    #   person.name = 'robert'
+    #   person.changed_attributes # => {"name" => "bob"}
+    def changed_attributes
+      # This should only be set by methods which will call changed_attributes
+      # multiple times when it is known that the computed value cannot change.
+      if defined?(@cached_changed_attributes)
+        @cached_changed_attributes
+      else
+        attributes_changed_by_setter.reverse_merge(mutations_from_database.changed_values).freeze
+      end
+    end
+
     # Returns a hash of changed attributes indicating their original
     # and new values like <tt>attr => [original value, new value]</tt>.
     #
@@ -153,7 +228,9 @@ module ActiveModel
     #   person.name = 'bob'
     #   person.changes # => { "name" => ["bill", "bob"] }
     def changes
-      ActiveSupport::HashWithIndifferentAccess[changed.map { |attr| [attr, attribute_change(attr)] }]
+      cache_changed_attributes do
+        ActiveSupport::HashWithIndifferentAccess[changed.map { |attr| [attr, attribute_change(attr)] }]
+      end
     end
 
     # Returns a hash of attributes that were changed before the model was saved.
@@ -164,45 +241,51 @@ module ActiveModel
     #   person.previous_changes # => {"name" => ["bob", "robert"]}
     def previous_changes
       @previously_changed ||= ActiveSupport::HashWithIndifferentAccess.new
+      @previously_changed.merge(mutations_before_last_save.changes)
     end
 
-    # Returns a hash of the attributes with unsaved changes indicating their original
-    # values like <tt>attr => original value</tt>.
-    #
-    #   person.name # => "bob"
-    #   person.name = 'robert'
-    #   person.changed_attributes # => {"name" => "bob"}
-    def changed_attributes
-      @changed_attributes ||= ActiveSupport::HashWithIndifferentAccess.new
+    def attribute_changed_in_place?(attr_name) # :nodoc:
+      mutations_from_database.changed_in_place?(attr_name)
     end
 
-    # Handles <tt>*_changed?</tt> for +method_missing+.
-    def attribute_changed?(attr, from: OPTION_NOT_GIVEN, to: OPTION_NOT_GIVEN) # :nodoc:
-      !!changes_include?(attr) &&
-        (to == OPTION_NOT_GIVEN || to == __send__(attr)) &&
-        (from == OPTION_NOT_GIVEN || from == changed_attributes[attr])
-    end
+    private
+      def clear_attribute_change(attr_name)
+        mutations_from_database.forget_change(attr_name)
+      end
 
-    # Handles <tt>*_was</tt> for +method_missing+.
-    def attribute_was(attr) # :nodoc:
-      attribute_changed?(attr) ? changed_attributes[attr] : __send__(attr)
-    end
+      def mutations_from_database
+        unless defined?(@mutations_from_database)
+          @mutations_from_database = nil
+        end
+        @mutations_from_database ||= if defined?(@attributes)
+          ActiveModel::AttributeMutationTracker.new(@attributes)
+        else
+          NullMutationTracker.instance
+        end
+      end
 
-    # Handles <tt>*_previously_changed?</tt> for +method_missing+.
-    def attribute_previously_changed?(attr) #:nodoc:
-      previous_changes_include?(attr)
-    end
+      def forget_attribute_assignments
+        @attributes = @attributes.map(&:forgetting_assignment) if defined?(@attributes)
+      end
 
-    # Restore all previous data of the provided attributes.
-    def restore_attributes(attributes = changed)
-      attributes.each { |attr| restore_attribute! attr }
-    end
+      def mutations_before_last_save
+        @mutations_before_last_save ||= ActiveModel::NullMutationTracker.instance
+      end
 
-    private
+      def cache_changed_attributes
+        @cached_changed_attributes = changed_attributes
+        yield
+      ensure
+        clear_changed_attributes_cache
+      end
+
+      def clear_changed_attributes_cache
+        remove_instance_variable(:@cached_changed_attributes) if defined?(@cached_changed_attributes)
+      end
 
       # Returns +true+ if attr_name is changed, +false+ otherwise.
       def changes_include?(attr_name)
-        attributes_changed_by_setter.include?(attr_name)
+        attributes_changed_by_setter.include?(attr_name) || mutations_from_database.changed?(attr_name)
       end
       alias attribute_changed_by_setter? changes_include?
 
@@ -212,21 +295,9 @@ module ActiveModel
         previous_changes.include?(attr_name)
       end
 
-      # Removes current changes and makes them accessible through +previous_changes+.
-      def changes_applied # :doc:
-        @previously_changed = changes
-        @changed_attributes = ActiveSupport::HashWithIndifferentAccess.new
-      end
-
-      # Clears all dirty data: current changes and previous changes.
-      def clear_changes_information # :doc:
-        @previously_changed = ActiveSupport::HashWithIndifferentAccess.new
-        @changed_attributes = ActiveSupport::HashWithIndifferentAccess.new
-      end
-
       # Handles <tt>*_change</tt> for +method_missing+.
       def attribute_change(attr)
-        [changed_attributes[attr], __send__(attr)] if attribute_changed?(attr)
+        [changed_attributes[attr], _read_attribute(attr)] if attribute_changed?(attr)
       end
 
       # Handles <tt>*_previous_change</tt> for +method_missing+.
@@ -236,15 +307,16 @@ module ActiveModel
 
       # Handles <tt>*_will_change!</tt> for +method_missing+.
       def attribute_will_change!(attr)
-        return if attribute_changed?(attr)
+        unless attribute_changed?(attr)
+          begin
+            value = _read_attribute(attr)
+            value = value.duplicable? ? value.clone : value
+          rescue TypeError, NoMethodError
+          end
 
-        begin
-          value = __send__(attr)
-          value = value.duplicable? ? value.clone : value
-        rescue TypeError, NoMethodError
+          set_attribute_was(attr, value)
         end
-
-        set_attribute_was(attr, value)
+        mutations_from_database.force_change(attr)
       end
 
       # Handles <tt>restore_*!</tt> for +method_missing+.
@@ -255,18 +327,13 @@ module ActiveModel
         end
       end
 
-      # This is necessary because `changed_attributes` might be overridden in
-      # other implementations (e.g. in `ActiveRecord`)
-      alias_method :attributes_changed_by_setter, :changed_attributes # :nodoc:
+      def attributes_changed_by_setter
+        @attributes_changed_by_setter ||= ActiveSupport::HashWithIndifferentAccess.new
+      end
 
       # Force an attribute to have a particular "before" value
       def set_attribute_was(attr, old_value)
         attributes_changed_by_setter[attr] = old_value
       end
-
-      # Remove changes information for the provided attributes.
-      def clear_attribute_changes(attributes) # :doc:
-        attributes_changed_by_setter.except!(*attributes)
-      end
   end
 end
diff --git a/activemodel/lib/active_model/errors.rb b/activemodel/lib/active_model/errors.rb
index 6f2c8c1c53..275e3f1313 100644
--- a/activemodel/lib/active_model/errors.rb
+++ b/activemodel/lib/active_model/errors.rb
@@ -1,7 +1,9 @@
-require 'active_support/core_ext/array/conversions'
-require 'active_support/core_ext/string/inflections'
-require 'active_support/core_ext/object/deep_dup'
-require 'active_support/core_ext/string/filters'
+# frozen_string_literal: true
+
+require "active_support/core_ext/array/conversions"
+require "active_support/core_ext/string/inflections"
+require "active_support/core_ext/object/deep_dup"
+require "active_support/core_ext/string/filters"
 
 module ActiveModel
   # == Active \Model \Errors
@@ -93,6 +95,18 @@ module ActiveModel
       @details  = other.details.dup
     end
 
+    # Merges the errors from <tt>other</tt>.
+    #
+    # other - The ActiveModel::Errors instance.
+    #
+    # Examples
+    #
+    #   person.errors.merge!(other)
+    def merge!(other)
+      @messages.merge!(other.messages) { |_, ary1, ary2| ary1 + ary2 }
+      @details.merge!(other.details) { |_, ary1, ary2| ary1 + ary2 }
+    end
+
     # Clear the error messages.
     #
     #   person.errors.full_messages # => ["name cannot be nil"]
@@ -110,49 +124,21 @@ module ActiveModel
     #   person.errors.include?(:name) # => true
     #   person.errors.include?(:age)  # => false
     def include?(attribute)
+      attribute = attribute.to_sym
       messages.key?(attribute) && messages[attribute].present?
     end
     alias :has_key? :include?
     alias :key? :include?
 
-    # Get messages for +key+.
-    #
-    #   person.errors.messages   # => {:name=>["cannot be nil"]}
-    #   person.errors.get(:name) # => ["cannot be nil"]
-    #   person.errors.get(:age)  # => []
-    def get(key)
-      ActiveSupport::Deprecation.warn(<<-MESSAGE.squish)
-        ActiveModel::Errors#get is deprecated and will be removed in Rails 5.1.
-
-        To achieve the same use model.errors[:#{key}].
-      MESSAGE
-
-      messages[key]
-    end
-
-    # Set messages for +key+ to +value+.
-    #
-    #   person.errors[:name] # => ["cannot be nil"]
-    #   person.errors.set(:name, ["can't be nil"])
-    #   person.errors[:name] # => ["can't be nil"]
-    def set(key, value)
-      ActiveSupport::Deprecation.warn(<<-MESSAGE.squish)
-        ActiveModel::Errors#set is deprecated and will be removed in Rails 5.1.
-
-        Use model.errors.add(:#{key}, #{value.inspect}) instead.
-      MESSAGE
-
-      messages[key] = value
-    end
-
     # Delete messages for +key+. Returns the deleted messages.
     #
-    #   person.errors[:name]    # => ["cannot be nil"]
+    #   person.errors[:name]        # => ["cannot be nil"]
     #   person.errors.delete(:name) # => ["cannot be nil"]
-    #   person.errors[:name]    # => []
+    #   person.errors[:name]        # => []
     def delete(key)
-      details.delete(key)
-      messages.delete(key)
+      attribute = key.to_sym
+      details.delete(attribute)
+      messages.delete(attribute)
     end
 
     # When passed a symbol or a name of a method, returns an array of errors
@@ -160,33 +146,10 @@ module ActiveModel
     #
     #   person.errors[:name]  # => ["cannot be nil"]
     #   person.errors['name'] # => ["cannot be nil"]
-    #
-    # Note that, if you try to get errors of an attribute which has
-    # no errors associated with it, this method will instantiate
-    # an empty error list for it and +keys+ will return an array
-    # of error keys which includes this attribute.
-    #
-    #   person.errors.keys    # => []
-    #   person.errors[:name]  # => []
-    #   person.errors.keys    # => [:name]
     def [](attribute)
       messages[attribute.to_sym]
     end
 
-    # Adds to the supplied attribute the supplied error message.
-    #
-    #   person.errors[:name] = "must be set"
-    #   person.errors[:name] # => ['must be set']
-    def []=(attribute, error)
-      ActiveSupport::Deprecation.warn(<<-MESSAGE.squish)
-        ActiveModel::Errors#[]= is deprecated and will be removed in Rails 5.1.
-
-        Use model.errors.add(:#{attribute}, #{error.inspect}) instead.
-      MESSAGE
-
-      messages[attribute.to_sym] << error
-    end
-
     # Iterates through each error key, value pair in the error messages hash.
     # Yields the attribute and the error for that attribute. If the attribute
     # has more than one error message, yields once for each error message.
@@ -223,7 +186,9 @@ module ActiveModel
     #   person.errors.messages # => {:name=>["cannot be nil", "must be specified"]}
     #   person.errors.values   # => [["cannot be nil", "must be specified"]]
     def values
-      messages.values
+      messages.select do |key, value|
+        !value.empty?
+      end.values
     end
 
     # Returns all message keys.
@@ -231,7 +196,9 @@ module ActiveModel
     #   person.errors.messages # => {:name=>["cannot be nil", "must be specified"]}
     #   person.errors.keys     # => [:name]
     def keys
-      messages.keys
+      messages.select do |key, value|
+        !value.empty?
+      end.keys
     end
 
     # Returns +true+ if no errors are found, +false+ otherwise.
@@ -255,7 +222,7 @@ module ActiveModel
     #   #    <error>name can't be blank</error>
     #   #    <error>name must be specified</error>
     #   #  </errors>
-    def to_xml(options={})
+    def to_xml(options = {})
       to_a.to_xml({ root: "errors", skip_types: true }.merge!(options))
     end
 
@@ -265,7 +232,7 @@ module ActiveModel
     #
     #   person.errors.as_json                      # => {:name=>["cannot be nil"]}
     #   person.errors.as_json(full_messages: true) # => {:name=>["name cannot be nil"]}
-    def as_json(options=nil)
+    def as_json(options = nil)
       to_hash(options && options[:full_messages])
     end
 
@@ -276,11 +243,11 @@ module ActiveModel
     #   person.errors.to_hash(true) # => {:name=>["name cannot be nil"]}
     def to_hash(full_messages = false)
       if full_messages
-        self.messages.each_with_object({}) do |(attribute, array), messages|
+        messages.each_with_object({}) do |(attribute, array), messages|
           messages[attribute] = array.map { |message| full_message(attribute, message) }
         end
       else
-        self.messages.dup
+        without_default_proc(messages)
       end
     end
 
@@ -338,58 +305,30 @@ module ActiveModel
       messages[attribute.to_sym] << message
     end
 
-    # Will add an error message to each of the attributes in +attributes+
-    # that is empty.
-    #
-    #   person.errors.add_on_empty(:name)
-    #   person.errors.messages
-    #   # => {:name=>["can't be empty"]}
-    def add_on_empty(attributes, options = {})
-      ActiveSupport::Deprecation.warn(<<-MESSAGE.squish)
-        ActiveModel::Errors#add_on_empty is deprecated and will be removed in Rails 5.1.
-
-        To achieve the same use:
-
-          errors.add(attribute, :empty, options) if value.nil? || value.empty?
-      MESSAGE
-
-      Array(attributes).each do |attribute|
-        value = @base.send(:read_attribute_for_validation, attribute)
-        is_empty = value.respond_to?(:empty?) ? value.empty? : false
-        add(attribute, :empty, options) if value.nil? || is_empty
-      end
-    end
-
-    # Will add an error message to each of the attributes in +attributes+ that
-    # is blank (using Object#blank?).
-    #
-    #   person.errors.add_on_blank(:name)
-    #   person.errors.messages
-    #   # => {:name=>["can't be blank"]}
-    def add_on_blank(attributes, options = {})
-      ActiveSupport::Deprecation.warn(<<-MESSAGE.squish)
-        ActiveModel::Errors#add_on_blank is deprecated and will be removed in Rails 5.1.
-
-        To achieve the same use:
-
-          errors.add(attribute, :empty, options) if value.blank?
-      MESSAGE
-
-      Array(attributes).each do |attribute|
-        value = @base.send(:read_attribute_for_validation, attribute)
-        add(attribute, :blank, options) if value.blank?
-      end
-    end
-
     # Returns +true+ if an error on the attribute with the given message is
-    # present, +false+ otherwise. +message+ is treated the same as for +add+.
+    # present, or +false+ otherwise. +message+ is treated the same as for +add+.
     #
     #   person.errors.add :name, :blank
-    #   person.errors.added? :name, :blank # => true
+    #   person.errors.added? :name, :blank           # => true
+    #   person.errors.added? :name, "can't be blank" # => true
+    #
+    # If the error message requires an option, then it returns +true+ with
+    # the correct option, or +false+ with an incorrect or missing option.
+    #
+    #  person.errors.add :name, :too_long, { count: 25 }
+    #  person.errors.added? :name, :too_long, count: 25                     # => true
+    #  person.errors.added? :name, "is too long (maximum is 25 characters)" # => true
+    #  person.errors.added? :name, :too_long, count: 24                     # => false
+    #  person.errors.added? :name, :too_long                                # => false
+    #  person.errors.added? :name, "is too long"                            # => false
     def added?(attribute, message = :invalid, options = {})
-      message = message.call if message.respond_to?(:call)
-      message = normalize_message(attribute, message, options)
-      self[attribute].include? message
+      if message.is_a? Symbol
+        self.details[attribute].map { |e| e[:error] }.include? message
+      else
+        message = message.call if message.respond_to?(:call)
+        message = normalize_message(attribute, message, options)
+        self[attribute].include? message
+      end
     end
 
     # Returns all the full error messages in an array.
@@ -418,6 +357,7 @@ module ActiveModel
     #   person.errors.full_messages_for(:name)
     #   # => ["Name is too short (minimum is 5 characters)", "Name can't be blank"]
     def full_messages_for(attribute)
+      attribute = attribute.to_sym
       messages[attribute].map { |message| full_message(attribute, message) }
     end
 
@@ -426,13 +366,12 @@ module ActiveModel
     #   person.errors.full_message(:name, 'is invalid') # => "Name is invalid"
     def full_message(attribute, message)
       return message if attribute == :base
-      attr_name = attribute.to_s.tr('.', '_').humanize
+      attr_name = attribute.to_s.tr(".", "_").humanize
       attr_name = @base.class.human_attribute_name(attribute, default: attr_name)
-      I18n.t(:"errors.format", {
+      I18n.t(:"errors.format",
         default:  "%{attribute} %{message}",
         attribute: attr_name,
-        message:   message
-      })
+        message:   message)
     end
 
     # Translates an error message in its default scope
@@ -463,21 +402,19 @@ module ActiveModel
       type = options.delete(:message) if options[:message].is_a?(Symbol)
 
       if @base.class.respond_to?(:i18n_scope)
-        defaults = @base.class.lookup_ancestors.map do |klass|
-          [ :"#{@base.class.i18n_scope}.errors.models.#{klass.model_name.i18n_key}.attributes.#{attribute}.#{type}",
-            :"#{@base.class.i18n_scope}.errors.models.#{klass.model_name.i18n_key}.#{type}" ]
+        i18n_scope = @base.class.i18n_scope.to_s
+        defaults = @base.class.lookup_ancestors.flat_map do |klass|
+          [ :"#{i18n_scope}.errors.models.#{klass.model_name.i18n_key}.attributes.#{attribute}.#{type}",
+            :"#{i18n_scope}.errors.models.#{klass.model_name.i18n_key}.#{type}" ]
         end
+        defaults << :"#{i18n_scope}.errors.messages.#{type}"
       else
         defaults = []
       end
 
-      defaults << :"#{@base.class.i18n_scope}.errors.messages.#{type}" if @base.class.respond_to?(:i18n_scope)
       defaults << :"errors.attributes.#{attribute}.#{type}"
       defaults << :"errors.messages.#{type}"
 
-      defaults.compact!
-      defaults.flatten!
-
       key = defaults.shift
       defaults = options.delete(:message) if options[:message]
       value = (attribute != :base ? @base.send(:read_attribute_for_validation, attribute) : nil)
@@ -493,16 +430,23 @@ module ActiveModel
       I18n.translate(key, options)
     end
 
-    def marshal_dump
+    def marshal_dump # :nodoc:
       [@base, without_default_proc(@messages), without_default_proc(@details)]
     end
 
-    def marshal_load(array)
+    def marshal_load(array) # :nodoc:
       @base, @messages, @details = array
       apply_default_array(@messages)
       apply_default_array(@details)
     end
 
+    def init_with(coder) # :nodoc:
+      coder.map.each { |k, v| instance_variable_set(:"@#{k}", v) }
+      @details ||= {}
+      apply_default_array(@messages)
+      apply_default_array(@details)
+    end
+
   private
     def normalize_message(attribute, message, options)
       case message
diff --git a/activemodel/lib/active_model/forbidden_attributes_protection.rb b/activemodel/lib/active_model/forbidden_attributes_protection.rb
index d2c6a89cc2..4b37f80c52 100644
--- a/activemodel/lib/active_model/forbidden_attributes_protection.rb
+++ b/activemodel/lib/active_model/forbidden_attributes_protection.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActiveModel
   # Raised when forbidden attributes are used for mass assignment.
   #
@@ -15,7 +17,7 @@ module ActiveModel
   end
 
   module ForbiddenAttributesProtection # :nodoc:
-    protected
+    private
       def sanitize_for_mass_assignment(attributes)
         if attributes.respond_to?(:permitted?)
           raise ActiveModel::ForbiddenAttributesError if !attributes.permitted?
diff --git a/activemodel/lib/active_model/gem_version.rb b/activemodel/lib/active_model/gem_version.rb
index 4a8ee915cf..3c344fe854 100644
--- a/activemodel/lib/active_model/gem_version.rb
+++ b/activemodel/lib/active_model/gem_version.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActiveModel
   # Returns the version of the currently loaded \Active \Model as a <tt>Gem::Version</tt>
   def self.gem_version
@@ -6,9 +8,9 @@ module ActiveModel
 
   module VERSION
     MAJOR = 5
-    MINOR = 1
+    MINOR = 2
     TINY  = 0
-    PRE   = "alpha"
+    PRE   = "beta2"
 
     STRING = [MAJOR, MINOR, TINY, PRE].compact.join(".")
   end
diff --git a/activemodel/lib/active_model/lint.rb b/activemodel/lib/active_model/lint.rb
index 010eaeb170..34d9ac6c96 100644
--- a/activemodel/lib/active_model/lint.rb
+++ b/activemodel/lib/active_model/lint.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActiveModel
   module Lint
     # == Active \Model \Lint \Tests
@@ -20,7 +22,6 @@ module ActiveModel
     # to <tt>to_model</tt>. It is perfectly fine for <tt>to_model</tt> to return
     # +self+.
     module Tests
-
       # Passes if the object's model responds to <tt>to_key</tt> and if calling
       # this method returns +nil+ when the object is not persisted.
       # Fails otherwise.
diff --git a/activemodel/lib/active_model/model.rb b/activemodel/lib/active_model/model.rb
index dac8d549a7..fc52cd4fdf 100644
--- a/activemodel/lib/active_model/model.rb
+++ b/activemodel/lib/active_model/model.rb
@@ -1,12 +1,13 @@
-module ActiveModel
+# frozen_string_literal: true
 
+module ActiveModel
   # == Active \Model \Basic \Model
   #
   # Includes the required interface for an object to interact with
-  # <tt>ActionPack</tt>, using different <tt>ActiveModel</tt> modules.
+  # Action Pack and Action View, using different Active Model modules.
   # It includes model name introspections, conversions, translations and
   # validations. Besides that, it allows you to initialize the object with a
-  # hash of attributes, pretty much like <tt>ActiveRecord</tt> does.
+  # hash of attributes, pretty much like Active Record does.
   #
   # A minimal implementation could be:
   #
@@ -76,7 +77,7 @@ module ActiveModel
     #   person = Person.new(name: 'bob', age: '18')
     #   person.name # => "bob"
     #   person.age  # => "18"
-    def initialize(attributes={})
+    def initialize(attributes = {})
       assign_attributes(attributes) if attributes
 
       super()
diff --git a/activemodel/lib/active_model/naming.rb b/activemodel/lib/active_model/naming.rb
index d86ef6224e..dfccd03cd8 100644
--- a/activemodel/lib/active_model/naming.rb
+++ b/activemodel/lib/active_model/naming.rb
@@ -1,7 +1,8 @@
-require 'active_support/core_ext/hash/except'
-require 'active_support/core_ext/module/introspection'
-require 'active_support/core_ext/module/remove_method'
-require 'active_support/core_ext/module/delegation'
+# frozen_string_literal: true
+
+require "active_support/core_ext/hash/except"
+require "active_support/core_ext/module/introspection"
+require "active_support/core_ext/module/redefine_method"
 
 module ActiveModel
   class Name
@@ -48,7 +49,7 @@ module ActiveModel
     # :method: <=>
     #
     # :call-seq:
-    #   ==(other)
+    #   <=>(other)
     #
     # Equivalent to <tt>String#<=></tt>.
     #
@@ -149,7 +150,7 @@ module ActiveModel
 
       raise ArgumentError, "Class name cannot be blank. You need to supply a name argument when anonymous class given" if @name.blank?
 
-      @unnamespaced = @name.sub(/^#{namespace.name}::/, '') if namespace
+      @unnamespaced = @name.sub(/^#{namespace.name}::/, "") if namespace
       @klass        = klass
       @singular     = _singularize(@name)
       @plural       = ActiveSupport::Inflector.pluralize(@singular)
@@ -174,7 +175,7 @@ module ActiveModel
     #   BlogPost.model_name.human # => "Blog post"
     #
     # Specify +options+ with additional translating options.
-    def human(options={})
+    def human(options = {})
       return @human unless @klass.respond_to?(:lookup_ancestors) &&
                            @klass.respond_to?(:i18n_scope)
 
@@ -191,9 +192,9 @@ module ActiveModel
 
     private
 
-    def _singularize(string)
-      ActiveSupport::Inflector.underscore(string).tr('/'.freeze, '_'.freeze)
-    end
+      def _singularize(string)
+        ActiveSupport::Inflector.underscore(string).tr("/".freeze, "_".freeze)
+      end
   end
 
   # == Active \Model \Naming
@@ -217,7 +218,7 @@ module ActiveModel
   # provided method below, or rolling your own is required.
   module Naming
     def self.extended(base) #:nodoc:
-      base.remove_possible_method :model_name
+      base.silence_redefinition_of_method :model_name
       base.delegate :model_name, to: :class
     end
 
@@ -235,7 +236,7 @@ module ActiveModel
     #   Person.model_name.plural   # => "people"
     def model_name
       @_model_name ||= begin
-        namespace = self.parents.detect do |n|
+        namespace = parents.detect do |n|
           n.respond_to?(:use_relative_model_naming?) && n.use_relative_model_naming?
         end
         ActiveModel::Name.new(self, namespace)
diff --git a/activemodel/lib/active_model/railtie.rb b/activemodel/lib/active_model/railtie.rb
index 1671eb7bd4..a9cdabba00 100644
--- a/activemodel/lib/active_model/railtie.rb
+++ b/activemodel/lib/active_model/railtie.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require "active_model"
 require "rails"
 
diff --git a/activemodel/lib/active_model/secure_password.rb b/activemodel/lib/active_model/secure_password.rb
index 89da74efa8..86f051f5ce 100644
--- a/activemodel/lib/active_model/secure_password.rb
+++ b/activemodel/lib/active_model/secure_password.rb
@@ -1,9 +1,11 @@
+# frozen_string_literal: true
+
 module ActiveModel
   module SecurePassword
     extend ActiveSupport::Concern
 
-    # BCrypt hash function can handle maximum 72 characters, and if we pass
-    # password of length more than 72 characters it ignores extra characters.
+    # BCrypt hash function can handle maximum 72 bytes, and if we pass
+    # password of length more than 72 bytes it ignores extra characters.
     # Hence need to put a restriction on password length.
     MAX_PASSWORD_LENGTH_ALLOWED = 72
 
@@ -18,7 +20,7 @@ module ActiveModel
       #
       # The following validations are added automatically:
       # * Password must be present on creation
-      # * Password length should be less than or equal to 72 characters
+      # * Password length should be less than or equal to 72 bytes
       # * Confirmation of password (using a +password_confirmation+ attribute)
       #
       # If password confirmation validation is not needed, simply leave out the
@@ -55,7 +57,7 @@ module ActiveModel
         # This is to avoid ActiveModel (and by extension the entire framework)
         # being dependent on a binary library.
         begin
-          require 'bcrypt'
+          require "bcrypt"
         rescue LoadError
           $stderr.puts "You don't have bcrypt installed in your application. Please add it to your Gemfile and run bundle install"
           raise
diff --git a/activemodel/lib/active_model/serialization.rb b/activemodel/lib/active_model/serialization.rb
index 70e10fa06d..47cb81bee5 100644
--- a/activemodel/lib/active_model/serialization.rb
+++ b/activemodel/lib/active_model/serialization.rb
@@ -1,5 +1,7 @@
-require 'active_support/core_ext/hash/except'
-require 'active_support/core_ext/hash/slice'
+# frozen_string_literal: true
+
+require "active_support/core_ext/hash/except"
+require "active_support/core_ext/hash/slice"
 
 module ActiveModel
   # == Active \Model \Serialization
diff --git a/activemodel/lib/active_model/serializers/json.rb b/activemodel/lib/active_model/serializers/json.rb
index b64a8299e6..25e1541d66 100644
--- a/activemodel/lib/active_model/serializers/json.rb
+++ b/activemodel/lib/active_model/serializers/json.rb
@@ -1,4 +1,6 @@
-require 'active_support/json'
+# frozen_string_literal: true
+
+require "active_support/json"
 
 module ActiveModel
   module Serializers
@@ -10,8 +12,7 @@ module ActiveModel
       included do
         extend ActiveModel::Naming
 
-        class_attribute :include_root_in_json, instance_writer: false
-        self.include_root_in_json = false
+        class_attribute :include_root_in_json, instance_writer: false, default: false
       end
 
       # Returns a hash representing the model. Some configuration can be
@@ -134,7 +135,7 @@ module ActiveModel
       #   person.name                  # => "bob"
       #   person.age                   # => 22
       #   person.awesome               # => true
-      def from_json(json, include_root=include_root_in_json)
+      def from_json(json, include_root = include_root_in_json)
         hash = ActiveSupport::JSON.decode(json)
         hash = hash.values.first if include_root
         self.attributes = hash
diff --git a/activemodel/lib/active_model/test_case.rb b/activemodel/lib/active_model/test_case.rb
deleted file mode 100644
index 5004855d56..0000000000
--- a/activemodel/lib/active_model/test_case.rb
+++ /dev/null
@@ -1,4 +0,0 @@
-module ActiveModel #:nodoc:
-  class TestCase < ActiveSupport::TestCase #:nodoc:
-  end
-end
diff --git a/activemodel/lib/active_model/translation.rb b/activemodel/lib/active_model/translation.rb
index 8470915abb..f3d0d3dc27 100644
--- a/activemodel/lib/active_model/translation.rb
+++ b/activemodel/lib/active_model/translation.rb
@@ -1,5 +1,6 @@
-module ActiveModel
+# frozen_string_literal: true
 
+module ActiveModel
   # == Active \Model \Translation
   #
   # Provides integration between your object and the Rails internationalization
@@ -31,7 +32,7 @@ module ActiveModel
     # ActiveModel::Errors#full_messages and
     # ActiveModel::Translation#human_attribute_name.
     def lookup_ancestors
-      self.ancestors.select { |x| x.respond_to?(:model_name) }
+      ancestors.select { |x| x.respond_to?(:model_name) }
     end
 
     # Transforms attribute names into a more human format, such as "First name"
@@ -45,7 +46,7 @@ module ActiveModel
       parts     = attribute.to_s.split(".")
       attribute = parts.pop
       namespace = parts.join("/") unless parts.empty?
-      attributes_scope = "#{self.i18n_scope}.attributes"
+      attributes_scope = "#{i18n_scope}.attributes"
 
       if namespace
         defaults = lookup_ancestors.map do |klass|
diff --git a/activemodel/lib/active_model/type.rb b/activemodel/lib/active_model/type.rb
index 6ec3452478..1d7a26fff5 100644
--- a/activemodel/lib/active_model/type.rb
+++ b/activemodel/lib/active_model/type.rb
@@ -1,22 +1,21 @@
-require 'active_model/type/helpers'
-require 'active_model/type/value'
-
-require 'active_model/type/big_integer'
-require 'active_model/type/binary'
-require 'active_model/type/boolean'
-require 'active_model/type/date'
-require 'active_model/type/date_time'
-require 'active_model/type/decimal'
-require 'active_model/type/decimal_without_scale'
-require 'active_model/type/float'
-require 'active_model/type/immutable_string'
-require 'active_model/type/integer'
-require 'active_model/type/string'
-require 'active_model/type/text'
-require 'active_model/type/time'
-require 'active_model/type/unsigned_integer'
-
-require 'active_model/type/registry'
+# frozen_string_literal: true
+
+require "active_model/type/helpers"
+require "active_model/type/value"
+
+require "active_model/type/big_integer"
+require "active_model/type/binary"
+require "active_model/type/boolean"
+require "active_model/type/date"
+require "active_model/type/date_time"
+require "active_model/type/decimal"
+require "active_model/type/float"
+require "active_model/type/immutable_string"
+require "active_model/type/integer"
+require "active_model/type/string"
+require "active_model/type/time"
+
+require "active_model/type/registry"
 
 module ActiveModel
   module Type
@@ -24,16 +23,8 @@ module ActiveModel
 
     class << self
       attr_accessor :registry # :nodoc:
-      delegate :add_modifier, to: :registry
-
-      # Add a new type to the registry, allowing it to be referenced as a
-      # symbol by ActiveModel::Attributes::ClassMethods#attribute.  If your
-      # type is only meant to be used with a specific database adapter, you can
-      # do so by passing +adapter: :postgresql+. If your type has the same
-      # name as a native type for the current adapter, an exception will be
-      # raised unless you specify an +:override+ option. +override: true+ will
-      # cause your type to be used instead of the native type. +override:
-      # false+ will cause the native type to be used over yours if one exists.
+
+      # Add a new type to the registry, allowing it to be gotten through ActiveModel::Type#lookup
       def register(type_name, klass = nil, **options, &block)
         registry.register(type_name, klass, **options, &block)
       end
@@ -41,6 +32,10 @@ module ActiveModel
       def lookup(*args, **kwargs) # :nodoc:
         registry.lookup(*args, **kwargs)
       end
+
+      def default_value # :nodoc:
+        @default_value ||= Value.new
+      end
     end
 
     register(:big_integer, Type::BigInteger)
@@ -53,7 +48,6 @@ module ActiveModel
     register(:immutable_string, Type::ImmutableString)
     register(:integer, Type::Integer)
     register(:string, Type::String)
-    register(:text, Type::Text)
     register(:time, Type::Time)
   end
 end
diff --git a/activemodel/lib/active_model/type/big_integer.rb b/activemodel/lib/active_model/type/big_integer.rb
index 4168cbfce7..89e43bcc5f 100644
--- a/activemodel/lib/active_model/type/big_integer.rb
+++ b/activemodel/lib/active_model/type/big_integer.rb
@@ -1,13 +1,15 @@
-require 'active_model/type/integer'
+# frozen_string_literal: true
+
+require "active_model/type/integer"
 
 module ActiveModel
   module Type
     class BigInteger < Integer # :nodoc:
       private
 
-      def max_value
-        ::Float::INFINITY
-      end
+        def max_value
+          ::Float::INFINITY
+        end
     end
   end
 end
diff --git a/activemodel/lib/active_model/type/binary.rb b/activemodel/lib/active_model/type/binary.rb
index a0cc45b4c3..dc2eca18be 100644
--- a/activemodel/lib/active_model/type/binary.rb
+++ b/activemodel/lib/active_model/type/binary.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActiveModel
   module Type
     class Binary < Value # :nodoc:
@@ -38,7 +40,7 @@ module ActiveModel
         alias_method :to_str, :to_s
 
         def hex
-          @value.unpack('H*')[0]
+          @value.unpack("H*")[0]
         end
 
         def ==(other)
diff --git a/activemodel/lib/active_model/type/boolean.rb b/activemodel/lib/active_model/type/boolean.rb
index c1bce98c87..bcdbab0343 100644
--- a/activemodel/lib/active_model/type/boolean.rb
+++ b/activemodel/lib/active_model/type/boolean.rb
@@ -1,21 +1,34 @@
+# frozen_string_literal: true
+
 module ActiveModel
   module Type
-    class Boolean < Value # :nodoc:
-      FALSE_VALUES = [false, 0, '0', 'f', 'F', 'false', 'FALSE', 'off', 'OFF'].to_set
+    # == Active \Model \Type \Boolean
+    #
+    # A class that behaves like a boolean type, including rules for coercion of user input.
+    #
+    # === Coercion
+    # Values set from user input will first be coerced into the appropriate ruby type.
+    # Coercion behavior is roughly mapped to Ruby's boolean semantics.
+    #
+    # - "false", "f" , "0", +0+ or any other value in +FALSE_VALUES+ will be coerced to +false+
+    # - Empty strings are coerced to +nil+
+    # - All other values will be coerced to +true+
+    class Boolean < Value
+      FALSE_VALUES = [false, 0, "0", "f", "F", "false", "FALSE", "off", "OFF"].to_set
 
-      def type
+      def type # :nodoc:
         :boolean
       end
 
       private
 
-      def cast_value(value)
-        if value == ''
-          nil
-        else
-          !FALSE_VALUES.include?(value)
+        def cast_value(value)
+          if value == ""
+            nil
+          else
+            !FALSE_VALUES.include?(value)
+          end
         end
-      end
     end
   end
 end
diff --git a/activemodel/lib/active_model/type/date.rb b/activemodel/lib/active_model/type/date.rb
index f74243a22c..8cecc16d0f 100644
--- a/activemodel/lib/active_model/type/date.rb
+++ b/activemodel/lib/active_model/type/date.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActiveModel
   module Type
     class Date < Value # :nodoc:
@@ -7,44 +9,48 @@ module ActiveModel
         :date
       end
 
+      def serialize(value)
+        cast(value)
+      end
+
       def type_cast_for_schema(value)
-        "'#{value.to_s(:db)}'"
+        value.to_s(:db).inspect
       end
 
       private
 
-      def cast_value(value)
-        if value.is_a?(::String)
-          return if value.empty?
-          fast_string_to_date(value) || fallback_string_to_date(value)
-        elsif value.respond_to?(:to_date)
-          value.to_date
-        else
-          value
+        def cast_value(value)
+          if value.is_a?(::String)
+            return if value.empty?
+            fast_string_to_date(value) || fallback_string_to_date(value)
+          elsif value.respond_to?(:to_date)
+            value.to_date
+          else
+            value
+          end
         end
-      end
 
-      ISO_DATE = /\A(\d{4})-(\d\d)-(\d\d)\z/
-      def fast_string_to_date(string)
-        if string =~ ISO_DATE
-          new_date $1.to_i, $2.to_i, $3.to_i
+        ISO_DATE = /\A(\d{4})-(\d\d)-(\d\d)\z/
+        def fast_string_to_date(string)
+          if string =~ ISO_DATE
+            new_date $1.to_i, $2.to_i, $3.to_i
+          end
         end
-      end
 
-      def fallback_string_to_date(string)
-        new_date(*::Date._parse(string, false).values_at(:year, :mon, :mday))
-      end
+        def fallback_string_to_date(string)
+          new_date(*::Date._parse(string, false).values_at(:year, :mon, :mday))
+        end
 
-      def new_date(year, mon, mday)
-        if year && year != 0
-          ::Date.new(year, mon, mday) rescue nil
+        def new_date(year, mon, mday)
+          if year && year != 0
+            ::Date.new(year, mon, mday) rescue nil
+          end
         end
-      end
 
-      def value_from_multiparameter_assignment(*)
-        time = super
-        time && time.to_date
-      end
+        def value_from_multiparameter_assignment(*)
+          time = super
+          time && time.to_date
+        end
     end
   end
 end
diff --git a/activemodel/lib/active_model/type/date_time.rb b/activemodel/lib/active_model/type/date_time.rb
index 2f2df4320f..9641bf45ee 100644
--- a/activemodel/lib/active_model/type/date_time.rb
+++ b/activemodel/lib/active_model/type/date_time.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActiveModel
   module Type
     class DateTime < Value # :nodoc:
@@ -10,35 +12,39 @@ module ActiveModel
         :datetime
       end
 
+      def serialize(value)
+        super(cast(value))
+      end
+
       private
 
-      def cast_value(value)
-        return apply_seconds_precision(value) unless value.is_a?(::String)
-        return if value.empty?
+        def cast_value(value)
+          return apply_seconds_precision(value) unless value.is_a?(::String)
+          return if value.empty?
 
-        fast_string_to_time(value) || fallback_string_to_time(value)
-      end
+          fast_string_to_time(value) || fallback_string_to_time(value)
+        end
 
-      # '0.123456' -> 123456
-      # '1.123456' -> 123456
-      def microseconds(time)
-        time[:sec_fraction] ? (time[:sec_fraction] * 1_000_000).to_i : 0
-      end
+        # '0.123456' -> 123456
+        # '1.123456' -> 123456
+        def microseconds(time)
+          time[:sec_fraction] ? (time[:sec_fraction] * 1_000_000).to_i : 0
+        end
 
-      def fallback_string_to_time(string)
-        time_hash = ::Date._parse(string)
-        time_hash[:sec_fraction] = microseconds(time_hash)
+        def fallback_string_to_time(string)
+          time_hash = ::Date._parse(string)
+          time_hash[:sec_fraction] = microseconds(time_hash)
 
-        new_time(*time_hash.values_at(:year, :mon, :mday, :hour, :min, :sec, :sec_fraction, :offset))
-      end
+          new_time(*time_hash.values_at(:year, :mon, :mday, :hour, :min, :sec, :sec_fraction, :offset))
+        end
 
-      def value_from_multiparameter_assignment(values_hash)
-        missing_parameter = (1..3).detect { |key| !values_hash.key?(key) }
-        if missing_parameter
-          raise ArgumentError, missing_parameter
+        def value_from_multiparameter_assignment(values_hash)
+          missing_parameter = (1..3).detect { |key| !values_hash.key?(key) }
+          if missing_parameter
+            raise ArgumentError, missing_parameter
+          end
+          super
         end
-        super
-      end
     end
   end
 end
diff --git a/activemodel/lib/active_model/type/decimal.rb b/activemodel/lib/active_model/type/decimal.rb
index 11ea327026..e8ee18c00e 100644
--- a/activemodel/lib/active_model/type/decimal.rb
+++ b/activemodel/lib/active_model/type/decimal.rb
@@ -1,9 +1,12 @@
+# frozen_string_literal: true
+
 require "bigdecimal/util"
 
 module ActiveModel
   module Type
     class Decimal < Value # :nodoc:
       include Helpers::Numeric
+      BIGDECIMAL_PRECISION = 18
 
       def type
         :decimal
@@ -15,46 +18,53 @@ module ActiveModel
 
       private
 
-      def cast_value(value)
-        casted_value = case value
-        when ::Float
-          convert_float_to_big_decimal(value)
-        when ::Numeric, ::String
-          BigDecimal(value, precision.to_i)
-        else
-          if value.respond_to?(:to_d)
-            value.to_d
-          else
-            cast_value(value.to_s)
-          end
-        end
+        def cast_value(value)
+          casted_value = \
+            case value
+            when ::Float
+              convert_float_to_big_decimal(value)
+            when ::Numeric
+              BigDecimal(value, precision || BIGDECIMAL_PRECISION)
+            when ::String
+              begin
+                value.to_d
+              rescue ArgumentError
+                BigDecimal(0)
+              end
+            else
+              if value.respond_to?(:to_d)
+                value.to_d
+              else
+                cast_value(value.to_s)
+              end
+            end
 
-        apply_scale(casted_value)
-      end
+          apply_scale(casted_value)
+        end
 
-      def convert_float_to_big_decimal(value)
-        if precision
-          BigDecimal(apply_scale(value), float_precision)
-        else
-          value.to_d
+        def convert_float_to_big_decimal(value)
+          if precision
+            BigDecimal(apply_scale(value), float_precision)
+          else
+            value.to_d
+          end
         end
-      end
 
-      def float_precision
-        if precision.to_i > ::Float::DIG + 1
-          ::Float::DIG + 1
-        else
-          precision.to_i
+        def float_precision
+          if precision.to_i > ::Float::DIG + 1
+            ::Float::DIG + 1
+          else
+            precision.to_i
+          end
         end
-      end
 
-      def apply_scale(value)
-        if scale
-          value.round(scale)
-        else
-          value
+        def apply_scale(value)
+          if scale
+            value.round(scale)
+          else
+            value
+          end
         end
-      end
     end
   end
 end
diff --git a/activemodel/lib/active_model/type/decimal_without_scale.rb b/activemodel/lib/active_model/type/decimal_without_scale.rb
deleted file mode 100644
index 129baa0c10..0000000000
--- a/activemodel/lib/active_model/type/decimal_without_scale.rb
+++ /dev/null
@@ -1,11 +0,0 @@
-require 'active_model/type/big_integer'
-
-module ActiveModel
-  module Type
-    class DecimalWithoutScale < BigInteger # :nodoc:
-      def type
-        :decimal
-      end
-    end
-  end
-end
diff --git a/activemodel/lib/active_model/type/float.rb b/activemodel/lib/active_model/type/float.rb
index 0f925bc7e1..9dbe32e5a6 100644
--- a/activemodel/lib/active_model/type/float.rb
+++ b/activemodel/lib/active_model/type/float.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActiveModel
   module Type
     class Float < Value # :nodoc:
@@ -7,19 +9,28 @@ module ActiveModel
         :float
       end
 
+      def type_cast_for_schema(value)
+        return "::Float::NAN" if value.try(:nan?)
+        case value
+        when ::Float::INFINITY then "::Float::INFINITY"
+        when -::Float::INFINITY then "-::Float::INFINITY"
+        else super
+        end
+      end
+
       alias serialize cast
 
       private
 
-      def cast_value(value)
-        case value
-        when ::Float then value
-        when "Infinity" then ::Float::INFINITY
-        when "-Infinity" then -::Float::INFINITY
-        when "NaN" then ::Float::NAN
-        else value.to_f
+        def cast_value(value)
+          case value
+          when ::Float then value
+          when "Infinity" then ::Float::INFINITY
+          when "-Infinity" then -::Float::INFINITY
+          when "NaN" then ::Float::NAN
+          else value.to_f
+          end
         end
-      end
     end
   end
 end
diff --git a/activemodel/lib/active_model/type/helpers.rb b/activemodel/lib/active_model/type/helpers.rb
index a805a359ab..403f0a9e6b 100644
--- a/activemodel/lib/active_model/type/helpers.rb
+++ b/activemodel/lib/active_model/type/helpers.rb
@@ -1,4 +1,6 @@
-require 'active_model/type/helpers/accepts_multiparameter_time'
-require 'active_model/type/helpers/numeric'
-require 'active_model/type/helpers/mutable'
-require 'active_model/type/helpers/time_value'
+# frozen_string_literal: true
+
+require "active_model/type/helpers/accepts_multiparameter_time"
+require "active_model/type/helpers/numeric"
+require "active_model/type/helpers/mutable"
+require "active_model/type/helpers/time_value"
diff --git a/activemodel/lib/active_model/type/helpers/accepts_multiparameter_time.rb b/activemodel/lib/active_model/type/helpers/accepts_multiparameter_time.rb
index facea12704..ad891f841e 100644
--- a/activemodel/lib/active_model/type/helpers/accepts_multiparameter_time.rb
+++ b/activemodel/lib/active_model/type/helpers/accepts_multiparameter_time.rb
@@ -1,7 +1,9 @@
+# frozen_string_literal: true
+
 module ActiveModel
   module Type
-    module Helpers
-      class AcceptsMultiparameterTime < Module # :nodoc:
+    module Helpers # :nodoc: all
+      class AcceptsMultiparameterTime < Module
         def initialize(defaults: {})
           define_method(:cast) do |value|
             if value.is_a?(Hash)
@@ -19,6 +21,10 @@ module ActiveModel
             end
           end
 
+          define_method(:value_constructed_by_mass_assignment?) do |value|
+            value.is_a?(Hash)
+          end
+
           define_method(:value_from_multiparameter_assignment) do |values_hash|
             defaults.each do |k, v|
               values_hash[k] ||= v
diff --git a/activemodel/lib/active_model/type/helpers/mutable.rb b/activemodel/lib/active_model/type/helpers/mutable.rb
index 4dddbe4e5e..1cbea644c4 100644
--- a/activemodel/lib/active_model/type/helpers/mutable.rb
+++ b/activemodel/lib/active_model/type/helpers/mutable.rb
@@ -1,7 +1,9 @@
+# frozen_string_literal: true
+
 module ActiveModel
   module Type
-    module Helpers
-      module Mutable # :nodoc:
+    module Helpers # :nodoc: all
+      module Mutable
         def cast(value)
           deserialize(serialize(value))
         end
diff --git a/activemodel/lib/active_model/type/helpers/numeric.rb b/activemodel/lib/active_model/type/helpers/numeric.rb
index c883010506..16e14f9e5f 100644
--- a/activemodel/lib/active_model/type/helpers/numeric.rb
+++ b/activemodel/lib/active_model/type/helpers/numeric.rb
@@ -1,14 +1,17 @@
+# frozen_string_literal: true
+
 module ActiveModel
   module Type
-    module Helpers
-      module Numeric # :nodoc:
+    module Helpers # :nodoc: all
+      module Numeric
         def cast(value)
-          value = case value
-                  when true then 1
-                  when false then 0
-                  when ::String then value.presence
-                  else value
-                  end
+          value = \
+            case value
+            when true then 1
+            when false then 0
+            when ::String then value.presence
+            else value
+            end
           super(value)
         end
 
@@ -18,16 +21,16 @@ module ActiveModel
 
         private
 
-        def number_to_non_number?(old_value, new_value_before_type_cast)
-          old_value != nil && non_numeric_string?(new_value_before_type_cast)
-        end
+          def number_to_non_number?(old_value, new_value_before_type_cast)
+            old_value != nil && non_numeric_string?(new_value_before_type_cast)
+          end
 
-        def non_numeric_string?(value)
-          # 'wibble'.to_i will give zero, we want to make sure
-          # that we aren't marking int zero to string zero as
-          # changed.
-          value.to_s !~ /\A-?\d+\.?\d*\z/
-        end
+          def non_numeric_string?(value)
+            # 'wibble'.to_i will give zero, we want to make sure
+            # that we aren't marking int zero to string zero as
+            # changed.
+            value.to_s !~ /\A-?\d+\.?\d*\z/
+          end
       end
     end
   end
diff --git a/activemodel/lib/active_model/type/helpers/time_value.rb b/activemodel/lib/active_model/type/helpers/time_value.rb
index 63993c0d93..250c4021c6 100644
--- a/activemodel/lib/active_model/type/helpers/time_value.rb
+++ b/activemodel/lib/active_model/type/helpers/time_value.rb
@@ -1,9 +1,11 @@
+# frozen_string_literal: true
+
 require "active_support/core_ext/time/zones"
 
 module ActiveModel
   module Type
-    module Helpers
-      module TimeValue # :nodoc:
+    module Helpers # :nodoc: all
+      module TimeValue
         def serialize(value)
           value = apply_seconds_precision(value)
 
@@ -19,7 +21,7 @@ module ActiveModel
         end
 
         def is_utc?
-          ::Time.zone_default.nil? || ::Time.zone_default =~ 'UTC'
+          ::Time.zone_default.nil? || ::Time.zone_default =~ "UTC"
         end
 
         def default_timezone
@@ -33,12 +35,12 @@ module ActiveModel
         def apply_seconds_precision(value)
           return value unless precision && value.respond_to?(:usec)
           number_of_insignificant_digits = 6 - precision
-          round_power = 10 ** number_of_insignificant_digits
-          value.change(usec: value.usec / round_power * round_power)
+          round_power = 10**number_of_insignificant_digits
+          value.change(usec: value.usec - value.usec % round_power)
         end
 
         def type_cast_for_schema(value)
-          "'#{value.to_s(:db)}'"
+          value.to_s(:db).inspect
         end
 
         def user_input_in_time_zone(value)
@@ -47,30 +49,30 @@ module ActiveModel
 
         private
 
-        def new_time(year, mon, mday, hour, min, sec, microsec, offset = nil)
-          # Treat 0000-00-00 00:00:00 as nil.
-          return if year.nil? || (year == 0 && mon == 0 && mday == 0)
+          def new_time(year, mon, mday, hour, min, sec, microsec, offset = nil)
+            # Treat 0000-00-00 00:00:00 as nil.
+            return if year.nil? || (year == 0 && mon == 0 && mday == 0)
 
-          if offset
-            time = ::Time.utc(year, mon, mday, hour, min, sec, microsec) rescue nil
-            return unless time
+            if offset
+              time = ::Time.utc(year, mon, mday, hour, min, sec, microsec) rescue nil
+              return unless time
 
-            time -= offset
-            is_utc? ? time : time.getlocal
-          else
-            ::Time.public_send(default_timezone, year, mon, mday, hour, min, sec, microsec) rescue nil
+              time -= offset
+              is_utc? ? time : time.getlocal
+            else
+              ::Time.public_send(default_timezone, year, mon, mday, hour, min, sec, microsec) rescue nil
+            end
           end
-        end
 
-        ISO_DATETIME = /\A(\d{4})-(\d\d)-(\d\d) (\d\d):(\d\d):(\d\d)(\.\d+)?\z/
+          ISO_DATETIME = /\A(\d{4})-(\d\d)-(\d\d) (\d\d):(\d\d):(\d\d)(\.\d+)?\z/
 
-        # Doesn't handle time zones.
-        def fast_string_to_time(string)
-          if string =~ ISO_DATETIME
-            microsec = ($7.to_r * 1_000_000).to_i
-            new_time $1.to_i, $2.to_i, $3.to_i, $4.to_i, $5.to_i, $6.to_i, microsec
+          # Doesn't handle time zones.
+          def fast_string_to_time(string)
+            if string =~ ISO_DATETIME
+              microsec = ($7.to_r * 1_000_000).to_i
+              new_time $1.to_i, $2.to_i, $3.to_i, $4.to_i, $5.to_i, $6.to_i, microsec
+            end
           end
-        end
       end
     end
   end
diff --git a/activemodel/lib/active_model/type/immutable_string.rb b/activemodel/lib/active_model/type/immutable_string.rb
index 20b8ca0cc4..826bd7038f 100644
--- a/activemodel/lib/active_model/type/immutable_string.rb
+++ b/activemodel/lib/active_model/type/immutable_string.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActiveModel
   module Type
     class ImmutableString < Value # :nodoc:
@@ -16,14 +18,15 @@ module ActiveModel
 
       private
 
-      def cast_value(value)
-        result = case value
-                 when true then "t"
-                 when false then "f"
-                 else value.to_s
-                 end
-        result.freeze
-      end
+        def cast_value(value)
+          result = \
+            case value
+            when true then "t"
+            when false then "f"
+            else value.to_s
+            end
+          result.freeze
+        end
     end
   end
 end
diff --git a/activemodel/lib/active_model/type/integer.rb b/activemodel/lib/active_model/type/integer.rb
index eea2280b22..fe396998a3 100644
--- a/activemodel/lib/active_model/type/integer.rb
+++ b/activemodel/lib/active_model/type/integer.rb
@@ -1,10 +1,12 @@
+# frozen_string_literal: true
+
 module ActiveModel
   module Type
     class Integer < Value # :nodoc:
       include Helpers::Numeric
 
       # Column storage size in bytes.
-      # 4 bytes means a MySQL int or Postgres integer as opposed to smallint etc.
+      # 4 bytes means an integer as opposed to smallint etc.
       DEFAULT_LIMIT = 4
 
       def initialize(*)
@@ -29,38 +31,40 @@ module ActiveModel
         result
       end
 
+      # TODO Change this to private once we've dropped Ruby 2.2 support.
+      # Workaround for Ruby 2.2 "private attribute?" warning.
       protected
 
-      attr_reader :range
+        attr_reader :range
 
       private
 
-      def cast_value(value)
-        case value
-        when true then 1
-        when false then 0
-        else
-          value.to_i rescue nil
+        def cast_value(value)
+          case value
+          when true then 1
+          when false then 0
+          else
+            value.to_i rescue nil
+          end
         end
-      end
 
-      def ensure_in_range(value)
-        unless range.cover?(value)
-          raise ActiveModel::RangeError, "#{value} is out of range for #{self.class} with limit #{_limit}"
+        def ensure_in_range(value)
+          unless range.cover?(value)
+            raise ActiveModel::RangeError, "#{value} is out of range for #{self.class} with limit #{_limit} bytes"
+          end
         end
-      end
 
-      def max_value
-        1 << (_limit * 8 - 1) # 8 bits per byte with one bit for sign
-      end
+        def max_value
+          1 << (_limit * 8 - 1) # 8 bits per byte with one bit for sign
+        end
 
-      def min_value
-        -max_value
-      end
+        def min_value
+          -max_value
+        end
 
-      def _limit
-        self.limit || DEFAULT_LIMIT
-      end
+        def _limit
+          limit || DEFAULT_LIMIT
+        end
     end
   end
 end
diff --git a/activemodel/lib/active_model/type/registry.rb b/activemodel/lib/active_model/type/registry.rb
index adc88eb624..7272d7b0c5 100644
--- a/activemodel/lib/active_model/type/registry.rb
+++ b/activemodel/lib/active_model/type/registry.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActiveModel
   # :stopdoc:
   module Type
@@ -21,19 +23,21 @@ module ActiveModel
         end
       end
 
+      # TODO Change this to private once we've dropped Ruby 2.2 support.
+      # Workaround for Ruby 2.2 "private attribute?" warning.
       protected
 
-      attr_reader :registrations
+        attr_reader :registrations
 
       private
 
-      def registration_klass
-        Registration
-      end
+        def registration_klass
+          Registration
+        end
 
-      def find_registration(symbol, *args)
-        registrations.find { |r| r.matches?(symbol, *args) }
-      end
+        def find_registration(symbol, *args)
+          registrations.find { |r| r.matches?(symbol, *args) }
+        end
     end
 
     class Registration
@@ -55,9 +59,11 @@ module ActiveModel
         type_name == name
       end
 
+      # TODO Change this to private once we've dropped Ruby 2.2 support.
+      # Workaround for Ruby 2.2 "private attribute?" warning.
       protected
 
-      attr_reader :name, :block
+        attr_reader :name, :block
     end
   end
   # :startdoc:
diff --git a/activemodel/lib/active_model/type/string.rb b/activemodel/lib/active_model/type/string.rb
index 8a91410998..36f13945b1 100644
--- a/activemodel/lib/active_model/type/string.rb
+++ b/activemodel/lib/active_model/type/string.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require "active_model/type/immutable_string"
 
 module ActiveModel
@@ -11,9 +13,14 @@ module ActiveModel
 
       private
 
-      def cast_value(value)
-        ::String.new(super)
-      end
+        def cast_value(value)
+          case value
+          when ::String then ::String.new(value)
+          when true then "t".freeze
+          when false then "f".freeze
+          else value.to_s
+          end
+        end
     end
   end
 end
diff --git a/activemodel/lib/active_model/type/text.rb b/activemodel/lib/active_model/type/text.rb
deleted file mode 100644
index 1ad04daba4..0000000000
--- a/activemodel/lib/active_model/type/text.rb
+++ /dev/null
@@ -1,11 +0,0 @@
-require 'active_model/type/string'
-
-module ActiveModel
-  module Type
-    class Text < String # :nodoc:
-      def type
-        :text
-      end
-    end
-  end
-end
diff --git a/activemodel/lib/active_model/type/time.rb b/activemodel/lib/active_model/type/time.rb
index 34e09f0aba..ad7ba0351a 100644
--- a/activemodel/lib/active_model/type/time.rb
+++ b/activemodel/lib/active_model/type/time.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActiveModel
   module Type
     class Time < Value # :nodoc:
@@ -25,22 +27,22 @@ module ActiveModel
 
       private
 
-      def cast_value(value)
-        return value unless value.is_a?(::String)
-        return if value.empty?
-
-        if value =~ /^2000-01-01/
-          dummy_time_value = value
-        else
-          dummy_time_value = "2000-01-01 #{value}"
+        def cast_value(value)
+          return value unless value.is_a?(::String)
+          return if value.empty?
+
+          if value.start_with?("2000-01-01")
+            dummy_time_value = value
+          else
+            dummy_time_value = "2000-01-01 #{value}"
+          end
+
+          fast_string_to_time(dummy_time_value) || begin
+            time_hash = ::Date._parse(dummy_time_value)
+            return if time_hash[:hour].nil?
+            new_time(*time_hash.values_at(:year, :mon, :mday, :hour, :min, :sec, :sec_fraction, :offset))
+          end
         end
-
-        fast_string_to_time(dummy_time_value) || begin
-          time_hash = ::Date._parse(dummy_time_value)
-          return if time_hash[:hour].nil?
-          new_time(*time_hash.values_at(:year, :mon, :mday, :hour, :min, :sec, :sec_fraction, :offset))
-        end
-      end
     end
   end
 end
diff --git a/activemodel/lib/active_model/type/unsigned_integer.rb b/activemodel/lib/active_model/type/unsigned_integer.rb
deleted file mode 100644
index 3f49f9f5f7..0000000000
--- a/activemodel/lib/active_model/type/unsigned_integer.rb
+++ /dev/null
@@ -1,15 +0,0 @@
-module ActiveModel
-  module Type
-    class UnsignedInteger < Integer # :nodoc:
-      private
-
-      def max_value
-        super * 2
-      end
-
-      def min_value
-        0
-      end
-    end
-  end
-end
diff --git a/activemodel/lib/active_model/type/value.rb b/activemodel/lib/active_model/type/value.rb
index 0d2d6873a8..a8ea6a2c22 100644
--- a/activemodel/lib/active_model/type/value.rb
+++ b/activemodel/lib/active_model/type/value.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActiveModel
   module Type
     class Value
@@ -84,6 +86,10 @@ module ActiveModel
         false
       end
 
+      def value_constructed_by_mass_assignment?(_value) # :nodoc:
+        false
+      end
+
       def map(value) # :nodoc:
         yield value
       end
@@ -105,12 +111,12 @@ module ActiveModel
 
       private
 
-      # Convenience method for types which do not need separate type casting
-      # behavior for user and database inputs. Called by Value#cast for
-      # values except +nil+.
-      def cast_value(value) # :doc:
-        value
-      end
+        # Convenience method for types which do not need separate type casting
+        # behavior for user and database inputs. Called by Value#cast for
+        # values except +nil+.
+        def cast_value(value) # :doc:
+          value
+        end
     end
   end
 end
diff --git a/activemodel/lib/active_model/validations.rb b/activemodel/lib/active_model/validations.rb
index a10d2285a2..7f14d102dd 100644
--- a/activemodel/lib/active_model/validations.rb
+++ b/activemodel/lib/active_model/validations.rb
@@ -1,9 +1,10 @@
-require 'active_support/core_ext/array/extract_options'
-require 'active_support/core_ext/hash/keys'
-require 'active_support/core_ext/hash/except'
+# frozen_string_literal: true
 
-module ActiveModel
+require "active_support/core_ext/array/extract_options"
+require "active_support/core_ext/hash/keys"
+require "active_support/core_ext/hash/except"
 
+module ActiveModel
   # == Active \Model \Validations
   #
   # Provides a full validation framework to your objects.
@@ -50,8 +51,7 @@ module ActiveModel
       private :validation_context=
       define_callbacks :validate, scope: :name
 
-      class_attribute :_validators, instance_writer: false
-      self._validators = Hash.new { |h,k| h[k] = [] }
+      class_attribute :_validators, instance_writer: false, default: Hash.new { |h, k| h[k] = [] }
     end
 
     module ClassMethods
@@ -69,7 +69,7 @@ module ActiveModel
       #
       # Options:
       # * <tt>:on</tt> - Specifies the contexts where this validation is active.
-      #   Runs in all validation contexts by default (nil). You can pass a symbol
+      #   Runs in all validation contexts by default +nil+. You can pass a symbol
       #   or an array of symbols. (e.g. <tt>on: :create</tt> or
       #   <tt>on: :custom_validation_context</tt> or
       #   <tt>on: [:create, :custom_validation_context]</tt>)
@@ -135,7 +135,7 @@ module ActiveModel
       #
       # Options:
       # * <tt>:on</tt> - Specifies the contexts where this validation is active.
-      #   Runs in all validation contexts by default (nil). You can pass a symbol
+      #   Runs in all validation contexts by default +nil+. You can pass a symbol
       #   or an array of symbols. (e.g. <tt>on: :create</tt> or
       #   <tt>on: :custom_validation_context</tt> or
       #   <tt>on: [:create, :custom_validation_context]</tt>)
@@ -148,6 +148,9 @@ module ActiveModel
       #   or <tt>unless: Proc.new { |user| user.signup_step <= 2 }</tt>). The
       #   method, proc or string should return or evaluate to a +true+ or +false+
       #   value.
+      #
+      # NOTE: Calling +validate+ multiple times on the same method will overwrite previous definitions.
+      #
       def validate(*args, &block)
         options = args.extract_options!
 
@@ -161,14 +164,14 @@ module ActiveModel
 
         if options.key?(:on)
           options = options.dup
+          options[:on] = Array(options[:on])
           options[:if] = Array(options[:if])
           options[:if].unshift ->(o) {
-            !(Array(options[:on]) & Array(o.validation_context)).empty?
+            !(options[:on] & Array(o.validation_context)).empty?
           }
         end
 
-        args << options
-        set_callback(:validate, *args, &block)
+        set_callback(:validate, *args, options, &block)
       end
 
       # List all validators that are being used to validate the model using
@@ -400,14 +403,14 @@ module ActiveModel
     #   end
     alias :read_attribute_for_validation :send
 
-  protected
+  private
 
-    def run_validations! #:nodoc:
+    def run_validations!
       _run_validate_callbacks
       errors.empty?
     end
 
-    def raise_validation_error
+    def raise_validation_error # :doc:
       raise(ValidationError.new(self))
     end
   end
@@ -433,4 +436,4 @@ module ActiveModel
   end
 end
 
-Dir[File.dirname(__FILE__) + "/validations/*.rb"].each { |file| require file }
+Dir[File.expand_path("validations/*.rb", __dir__)].each { |file| require file }
diff --git a/activemodel/lib/active_model/validations/absence.rb b/activemodel/lib/active_model/validations/absence.rb
index 75bf655578..385d9f27e0 100644
--- a/activemodel/lib/active_model/validations/absence.rb
+++ b/activemodel/lib/active_model/validations/absence.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActiveModel
   module Validations
     # == \Active \Model Absence Validator
@@ -22,7 +24,7 @@ module ActiveModel
       #
       # There is also a list of default options supported by every validator:
       # +:if+, +:unless+, +:on+, +:allow_nil+, +:allow_blank+, and +:strict+.
-      # See <tt>ActiveModel::Validation#validates</tt> for more information
+      # See <tt>ActiveModel::Validations#validates</tt> for more information
       def validates_absence_of(*attr_names)
         validates_with AbsenceValidator, _merge_attributes(attr_names)
       end
diff --git a/activemodel/lib/active_model/validations/acceptance.rb b/activemodel/lib/active_model/validations/acceptance.rb
index a04e5f347e..f35e4dec7f 100644
--- a/activemodel/lib/active_model/validations/acceptance.rb
+++ b/activemodel/lib/active_model/validations/acceptance.rb
@@ -1,5 +1,6 @@
-module ActiveModel
+# frozen_string_literal: true
 
+module ActiveModel
   module Validations
     class AcceptanceValidator < EachValidator # :nodoc:
       def initialize(options)
@@ -15,58 +16,60 @@ module ActiveModel
 
       private
 
-      def setup!(klass)
-        klass.include(LazilyDefineAttributes.new(AttributeDefinition.new(attributes)))
-      end
+        def setup!(klass)
+          klass.include(LazilyDefineAttributes.new(AttributeDefinition.new(attributes)))
+        end
 
-      def acceptable_option?(value)
-        Array(options[:accept]).include?(value)
-      end
+        def acceptable_option?(value)
+          Array(options[:accept]).include?(value)
+        end
 
-      class LazilyDefineAttributes < Module
-        def initialize(attribute_definition)
-          define_method(:respond_to_missing?) do |method_name, include_private=false|
-            super(method_name, include_private) || attribute_definition.matches?(method_name)
-          end
+        class LazilyDefineAttributes < Module
+          def initialize(attribute_definition)
+            define_method(:respond_to_missing?) do |method_name, include_private = false|
+              super(method_name, include_private) || attribute_definition.matches?(method_name)
+            end
 
-          define_method(:method_missing) do |method_name, *args, &block|
-            if attribute_definition.matches?(method_name)
-              attribute_definition.define_on(self.class)
-              send(method_name, *args, &block)
-            else
-              super(method_name, *args, &block)
+            define_method(:method_missing) do |method_name, *args, &block|
+              if attribute_definition.matches?(method_name)
+                attribute_definition.define_on(self.class)
+                send(method_name, *args, &block)
+              else
+                super(method_name, *args, &block)
+              end
             end
           end
         end
-      end
 
-      class AttributeDefinition
-        def initialize(attributes)
-          @attributes = attributes.map(&:to_s)
-        end
+        class AttributeDefinition
+          def initialize(attributes)
+            @attributes = attributes.map(&:to_s)
+          end
 
-        def matches?(method_name)
-          attr_name = convert_to_reader_name(method_name)
-          attributes.include?(attr_name)
-        end
+          def matches?(method_name)
+            attr_name = convert_to_reader_name(method_name)
+            attributes.include?(attr_name)
+          end
 
-        def define_on(klass)
-          attr_readers = attributes.reject { |name| klass.attribute_method?(name) }
-          attr_writers = attributes.reject { |name| klass.attribute_method?("#{name}=") }
-          klass.send(:attr_reader, *attr_readers)
-          klass.send(:attr_writer, *attr_writers)
-        end
+          def define_on(klass)
+            attr_readers = attributes.reject { |name| klass.attribute_method?(name) }
+            attr_writers = attributes.reject { |name| klass.attribute_method?("#{name}=") }
+            klass.send(:attr_reader, *attr_readers)
+            klass.send(:attr_writer, *attr_writers)
+          end
 
-        protected
+          # TODO Change this to private once we've dropped Ruby 2.2 support.
+          # Workaround for Ruby 2.2 "private attribute?" warning.
+          protected
 
-        attr_reader :attributes
+            attr_reader :attributes
 
-        private
+          private
 
-        def convert_to_reader_name(method_name)
-          method_name.to_s.chomp('=')
+            def convert_to_reader_name(method_name)
+              method_name.to_s.chomp("=")
+            end
         end
-      end
     end
 
     module HelperMethods
@@ -94,7 +97,7 @@ module ActiveModel
       #
       # There is also a list of default options supported by every validator:
       # +:if+, +:unless+, +:on+, +:allow_nil+, +:allow_blank+, and +:strict+.
-      # See <tt>ActiveModel::Validation#validates</tt> for more information.
+      # See <tt>ActiveModel::Validations#validates</tt> for more information.
       def validates_acceptance_of(*attr_names)
         validates_with AcceptanceValidator, _merge_attributes(attr_names)
       end
diff --git a/activemodel/lib/active_model/validations/callbacks.rb b/activemodel/lib/active_model/validations/callbacks.rb
index a201f72ed0..887d31ae2a 100644
--- a/activemodel/lib/active_model/validations/callbacks.rb
+++ b/activemodel/lib/active_model/validations/callbacks.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActiveModel
   module Validations
     # == Active \Model \Validation \Callbacks
@@ -23,7 +25,6 @@ module ActiveModel
       included do
         include ActiveSupport::Callbacks
         define_callbacks :validation,
-                         terminator: deprecated_false_terminator,
                          skip_after_callbacks_if_terminated: true,
                          scope: [:kind, :name]
       end
@@ -53,15 +54,18 @@ module ActiveModel
         #   person.valid? # => true
         #   person.name   # => "bob"
         def before_validation(*args, &block)
-          options = args.last
-          if options.is_a?(Hash) && options[:on]
-            options[:if] = Array(options[:if])
+          options = args.extract_options!
+
+          if options.key?(:on)
+            options = options.dup
             options[:on] = Array(options[:on])
+            options[:if] = Array(options[:if])
             options[:if].unshift ->(o) {
-              options[:on].include? o.validation_context
+              !(options[:on] & Array(o.validation_context)).empty?
             }
           end
-          set_callback(:validation, :before, *args, &block)
+
+          set_callback(:validation, :before, *args, options, &block)
         end
 
         # Defines a callback that will get called right after validation.
@@ -92,22 +96,25 @@ module ActiveModel
         #   person.status # => true
         def after_validation(*args, &block)
           options = args.extract_options!
+          options = options.dup
           options[:prepend] = true
-          options[:if] = Array(options[:if])
-          if options[:on]
+
+          if options.key?(:on)
             options[:on] = Array(options[:on])
+            options[:if] = Array(options[:if])
             options[:if].unshift ->(o) {
-              options[:on].include? o.validation_context
+              !(options[:on] & Array(o.validation_context)).empty?
             }
           end
-          set_callback(:validation, :after, *(args << options), &block)
+
+          set_callback(:validation, :after, *args, options, &block)
         end
       end
 
-    protected
+    private
 
       # Overwrite run validations to include callbacks.
-      def run_validations! #:nodoc:
+      def run_validations!
         _run_validation_callbacks { super }
       end
     end
diff --git a/activemodel/lib/active_model/validations/clusivity.rb b/activemodel/lib/active_model/validations/clusivity.rb
index d49af603bb..0b9b5ce6a1 100644
--- a/activemodel/lib/active_model/validations/clusivity.rb
+++ b/activemodel/lib/active_model/validations/clusivity.rb
@@ -1,4 +1,6 @@
-require 'active_support/core_ext/range'
+# frozen_string_literal: true
+
+require "active_support/core_ext/range"
 
 module ActiveModel
   module Validations
@@ -16,12 +18,12 @@ module ActiveModel
 
       def include?(record, value)
         members = if delimiter.respond_to?(:call)
-                    delimiter.call(record)
-                  elsif delimiter.respond_to?(:to_sym)
-                    record.send(delimiter)
-                  else
-                    delimiter
-                  end
+          delimiter.call(record)
+        elsif delimiter.respond_to?(:to_sym)
+          record.send(delimiter)
+        else
+          delimiter
+        end
 
         members.send(inclusion_method(members), value)
       end
diff --git a/activemodel/lib/active_model/validations/confirmation.rb b/activemodel/lib/active_model/validations/confirmation.rb
index 8f8ade90bb..1b5d5b09ab 100644
--- a/activemodel/lib/active_model/validations/confirmation.rb
+++ b/activemodel/lib/active_model/validations/confirmation.rb
@@ -1,5 +1,6 @@
-module ActiveModel
+# frozen_string_literal: true
 
+module ActiveModel
   module Validations
     class ConfirmationValidator < EachValidator # :nodoc:
       def initialize(options)
@@ -8,7 +9,7 @@ module ActiveModel
       end
 
       def validate_each(record, attribute, value)
-        if (confirmed = record.send("#{attribute}_confirmation"))
+        unless (confirmed = record.send("#{attribute}_confirmation")).nil?
           unless confirmation_value_equal?(record, attribute, value, confirmed)
             human_attribute_name = record.class.human_attribute_name(attribute)
             record.errors.add(:"#{attribute}_confirmation", :confirmation, options.except(:case_sensitive).merge!(attribute: human_attribute_name))
@@ -17,23 +18,23 @@ module ActiveModel
       end
 
       private
-      def setup!(klass)
-        klass.send(:attr_reader, *attributes.map do |attribute|
-          :"#{attribute}_confirmation" unless klass.method_defined?(:"#{attribute}_confirmation")
-        end.compact)
+        def setup!(klass)
+          klass.send(:attr_reader, *attributes.map do |attribute|
+            :"#{attribute}_confirmation" unless klass.method_defined?(:"#{attribute}_confirmation")
+          end.compact)
 
-        klass.send(:attr_writer, *attributes.map do |attribute|
-          :"#{attribute}_confirmation" unless klass.method_defined?(:"#{attribute}_confirmation=")
-        end.compact)
-      end
+          klass.send(:attr_writer, *attributes.map do |attribute|
+            :"#{attribute}_confirmation" unless klass.method_defined?(:"#{attribute}_confirmation=")
+          end.compact)
+        end
 
-      def confirmation_value_equal?(record, attribute, value, confirmed)
-        if !options[:case_sensitive] && value.is_a?(String)
-          value.casecmp(confirmed) == 0
-        else
-          value == confirmed
+        def confirmation_value_equal?(record, attribute, value, confirmed)
+          if !options[:case_sensitive] && value.is_a?(String)
+            value.casecmp(confirmed) == 0
+          else
+            value == confirmed
+          end
         end
-      end
     end
 
     module HelperMethods
@@ -70,7 +71,7 @@ module ActiveModel
       #
       # There is also a list of default options supported by every validator:
       # +:if+, +:unless+, +:on+, +:allow_nil+, +:allow_blank+, and +:strict+.
-      # See <tt>ActiveModel::Validation#validates</tt> for more information
+      # See <tt>ActiveModel::Validations#validates</tt> for more information
       def validates_confirmation_of(*attr_names)
         validates_with ConfirmationValidator, _merge_attributes(attr_names)
       end
diff --git a/activemodel/lib/active_model/validations/exclusion.rb b/activemodel/lib/active_model/validations/exclusion.rb
index 6f4276cc2a..3be7ab6ba8 100644
--- a/activemodel/lib/active_model/validations/exclusion.rb
+++ b/activemodel/lib/active_model/validations/exclusion.rb
@@ -1,7 +1,8 @@
+# frozen_string_literal: true
+
 require "active_model/validations/clusivity"
 
 module ActiveModel
-
   module Validations
     class ExclusionValidator < EachValidator # :nodoc:
       include Clusivity
@@ -39,7 +40,7 @@ module ActiveModel
       #
       # There is also a list of default options supported by every validator:
       # +:if+, +:unless+, +:on+, +:allow_nil+, +:allow_blank+, and +:strict+.
-      # See <tt>ActiveModel::Validation#validates</tt> for more information
+      # See <tt>ActiveModel::Validations#validates</tt> for more information
       def validates_exclusion_of(*attr_names)
         validates_with ExclusionValidator, _merge_attributes(attr_names)
       end
diff --git a/activemodel/lib/active_model/validations/format.rb b/activemodel/lib/active_model/validations/format.rb
index 46a2e54fba..7c3f091473 100644
--- a/activemodel/lib/active_model/validations/format.rb
+++ b/activemodel/lib/active_model/validations/format.rb
@@ -1,5 +1,6 @@
-module ActiveModel
+# frozen_string_literal: true
 
+module ActiveModel
   module Validations
     class FormatValidator < EachValidator # :nodoc:
       def validate_each(record, attribute, value)
@@ -8,7 +9,7 @@ module ActiveModel
           record_error(record, attribute, :with, value) if value.to_s !~ regexp
         elsif options[:without]
           regexp = option_call(record, :without)
-          record_error(record, attribute, :without, value) if value.to_s =~ regexp
+          record_error(record, attribute, :without, value) if regexp.match?(value.to_s)
         end
       end
 
@@ -23,33 +24,33 @@ module ActiveModel
 
       private
 
-      def option_call(record, name)
-        option = options[name]
-        option.respond_to?(:call) ? option.call(record) : option
-      end
+        def option_call(record, name)
+          option = options[name]
+          option.respond_to?(:call) ? option.call(record) : option
+        end
 
-      def record_error(record, attribute, name, value)
-        record.errors.add(attribute, :invalid, options.except(name).merge!(value: value))
-      end
+        def record_error(record, attribute, name, value)
+          record.errors.add(attribute, :invalid, options.except(name).merge!(value: value))
+        end
 
-      def check_options_validity(name)
-        if option = options[name]
-          if option.is_a?(Regexp)
-            if options[:multiline] != true && regexp_using_multiline_anchors?(option)
-              raise ArgumentError, "The provided regular expression is using multiline anchors (^ or $), " \
-              "which may present a security risk. Did you mean to use \\A and \\z, or forgot to add the " \
-              ":multiline => true option?"
+        def check_options_validity(name)
+          if option = options[name]
+            if option.is_a?(Regexp)
+              if options[:multiline] != true && regexp_using_multiline_anchors?(option)
+                raise ArgumentError, "The provided regular expression is using multiline anchors (^ or $), " \
+                "which may present a security risk. Did you mean to use \\A and \\z, or forgot to add the " \
+                ":multiline => true option?"
+              end
+            elsif !option.respond_to?(:call)
+              raise ArgumentError, "A regular expression or a proc or lambda must be supplied as :#{name}"
             end
-          elsif !option.respond_to?(:call)
-            raise ArgumentError, "A regular expression or a proc or lambda must be supplied as :#{name}"
           end
         end
-      end
 
-      def regexp_using_multiline_anchors?(regexp)
-        source = regexp.source
-        source.start_with?("^") || (source.end_with?("$") && !source.end_with?("\\$"))
-      end
+        def regexp_using_multiline_anchors?(regexp)
+          source = regexp.source
+          source.start_with?("^") || (source.end_with?("$") && !source.end_with?("\\$"))
+        end
     end
 
     module HelperMethods
@@ -104,7 +105,7 @@ module ActiveModel
       #
       # There is also a list of default options supported by every validator:
       # +:if+, +:unless+, +:on+, +:allow_nil+, +:allow_blank+, and +:strict+.
-      # See <tt>ActiveModel::Validation#validates</tt> for more information
+      # See <tt>ActiveModel::Validations#validates</tt> for more information
       def validates_format_of(*attr_names)
         validates_with FormatValidator, _merge_attributes(attr_names)
       end
diff --git a/activemodel/lib/active_model/validations/helper_methods.rb b/activemodel/lib/active_model/validations/helper_methods.rb
index 2176115334..730173f2f9 100644
--- a/activemodel/lib/active_model/validations/helper_methods.rb
+++ b/activemodel/lib/active_model/validations/helper_methods.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActiveModel
   module Validations
     module HelperMethods # :nodoc:
diff --git a/activemodel/lib/active_model/validations/inclusion.rb b/activemodel/lib/active_model/validations/inclusion.rb
index 03e0ef56d8..3104e7e329 100644
--- a/activemodel/lib/active_model/validations/inclusion.rb
+++ b/activemodel/lib/active_model/validations/inclusion.rb
@@ -1,7 +1,8 @@
+# frozen_string_literal: true
+
 require "active_model/validations/clusivity"
 
 module ActiveModel
-
   module Validations
     class InclusionValidator < EachValidator # :nodoc:
       include Clusivity
@@ -37,7 +38,7 @@ module ActiveModel
       #
       # There is also a list of default options supported by every validator:
       # +:if+, +:unless+, +:on+, +:allow_nil+, +:allow_blank+, and +:strict+.
-      # See <tt>ActiveModel::Validation#validates</tt> for more information
+      # See <tt>ActiveModel::Validations#validates</tt> for more information
       def validates_inclusion_of(*attr_names)
         validates_with InclusionValidator, _merge_attributes(attr_names)
       end
diff --git a/activemodel/lib/active_model/validations/length.rb b/activemodel/lib/active_model/validations/length.rb
index 79297ac119..d6c80b2c5d 100644
--- a/activemodel/lib/active_model/validations/length.rb
+++ b/activemodel/lib/active_model/validations/length.rb
@@ -1,4 +1,4 @@
-require "active_support/core_ext/string/strip"
+# frozen_string_literal: true
 
 module ActiveModel
   module Validations
@@ -6,7 +6,7 @@ module ActiveModel
       MESSAGES  = { is: :wrong_length, minimum: :too_short, maximum: :too_long }.freeze
       CHECKS    = { is: :==, minimum: :>=, maximum: :<= }.freeze
 
-      RESERVED_OPTIONS  = [:minimum, :maximum, :within, :is, :tokenizer, :too_short, :too_long]
+      RESERVED_OPTIONS = [:minimum, :maximum, :within, :is, :too_short, :too_long]
 
       def initialize(options)
         if range = (options.delete(:in) || options.delete(:within))
@@ -18,27 +18,6 @@ module ActiveModel
           options[:minimum] = 1
         end
 
-        if options[:tokenizer]
-          ActiveSupport::Deprecation.warn(<<-EOS.strip_heredoc)
-            The `:tokenizer` option is deprecated, and will be removed in Rails 5.1.
-            You can achieve the same functionality by defining an instance method
-            with the value that you want to validate the length of. For example,
-
-                validates_length_of :essay, minimum: 100,
-                  tokenizer: ->(str) { str.scan(/\w+/) }
-
-            should be written as
-
-                validates_length_of :words_in_essay, minimum: 100
-
-                private
-
-                def words_in_essay
-                  essay.scan(/\w+/)
-                end
-          EOS
-        end
-
         super
       end
 
@@ -46,20 +25,19 @@ module ActiveModel
         keys = CHECKS.keys & options.keys
 
         if keys.empty?
-          raise ArgumentError, 'Range unspecified. Specify the :in, :within, :maximum, :minimum, or :is option.'
+          raise ArgumentError, "Range unspecified. Specify the :in, :within, :maximum, :minimum, or :is option."
         end
 
         keys.each do |key|
           value = options[key]
 
-          unless (value.is_a?(Integer) && value >= 0) || value == Float::INFINITY
-            raise ArgumentError, ":#{key} must be a nonnegative Integer or Infinity"
+          unless (value.is_a?(Integer) && value >= 0) || value == Float::INFINITY || value.is_a?(Symbol) || value.is_a?(Proc)
+            raise ArgumentError, ":#{key} must be a nonnegative Integer, Infinity, Symbol, or Proc"
           end
         end
       end
 
       def validate_each(record, attribute, value)
-        value = tokenize(record, value)
         value_length = value.respond_to?(:length) ? value.length : value.to_s.length
         errors_options = options.except(*RESERVED_OPTIONS)
 
@@ -67,6 +45,12 @@ module ActiveModel
           next unless check_value = options[key]
 
           if !value.nil? || skip_nil_check?(key)
+            case check_value
+            when Proc
+              check_value = check_value.call(record)
+            when Symbol
+              check_value = record.send(check_value)
+            end
             next if value_length.send(validity_check, check_value)
           end
 
@@ -80,24 +64,12 @@ module ActiveModel
       end
 
       private
-      def tokenize(record, value)
-        tokenizer = options[:tokenizer]
-        if tokenizer && value.kind_of?(String)
-          if tokenizer.kind_of?(Proc)
-            tokenizer.call(value)
-          elsif record.respond_to?(tokenizer)
-            record.send(tokenizer, value)
-          end
-        end || value
-      end
-
-      def skip_nil_check?(key)
-        key == :maximum && options[:allow_nil].nil? && options[:allow_blank].nil?
-      end
+        def skip_nil_check?(key)
+          key == :maximum && options[:allow_nil].nil? && options[:allow_blank].nil?
+        end
     end
 
     module HelperMethods
-
       # Validates that the specified attributes match the length restrictions
       # supplied. Only one constraint option can be used at a time apart from
       # +:minimum+ and +:maximum+ that can be combined together:
@@ -146,7 +118,7 @@ module ActiveModel
       #
       # There is also a list of default options supported by every validator:
       # +:if+, +:unless+, +:on+ and +:strict+.
-      # See <tt>ActiveModel::Validation#validates</tt> for more information
+      # See <tt>ActiveModel::Validations#validates</tt> for more information
       def validates_length_of(*attr_names)
         validates_with LengthValidator, _merge_attributes(attr_names)
       end
diff --git a/activemodel/lib/active_model/validations/numericality.rb b/activemodel/lib/active_model/validations/numericality.rb
index 9a0a0655de..31750ba78e 100644
--- a/activemodel/lib/active_model/validations/numericality.rb
+++ b/activemodel/lib/active_model/validations/numericality.rb
@@ -1,5 +1,6 @@
-module ActiveModel
+# frozen_string_literal: true
 
+module ActiveModel
   module Validations
     class NumericalityValidator < EachValidator # :nodoc:
       CHECKS = { greater_than: :>, greater_than_or_equal_to: :>=,
@@ -27,8 +28,6 @@ module ActiveModel
           raw_value = value
         end
 
-        return if options[:allow_nil] && raw_value.nil?
-
         unless is_number?(raw_value)
           record.errors.add(attr_name, :not_a_number, filtered_options(raw_value))
           return
@@ -39,7 +38,9 @@ module ActiveModel
           return
         end
 
-        unless raw_value.is_a?(Numeric)
+        if raw_value.is_a?(Numeric)
+          value = raw_value
+        else
           value = parse_raw_value_as_a_number(raw_value)
         end
 
@@ -64,7 +65,7 @@ module ActiveModel
         end
       end
 
-    protected
+    private
 
       def is_number?(raw_value)
         !parse_raw_value_as_a_number(raw_value).nil?
@@ -73,6 +74,7 @@ module ActiveModel
       end
 
       def parse_raw_value_as_a_number(raw_value)
+        return raw_value.to_i if is_integer?(raw_value)
         Kernel.Float(raw_value) if raw_value !~ /\A0[xX]/
       end
 
@@ -97,8 +99,6 @@ module ActiveModel
         end
       end
 
-      private
-
       def record_attribute_changed_in_place?(record, attr_name)
         record.respond_to?(:attribute_changed_in_place?) &&
           record.attribute_changed_in_place?(attr_name.to_s)
@@ -108,7 +108,7 @@ module ActiveModel
     module HelperMethods
       # Validates whether the value of the specified attribute is numeric by
       # trying to convert it to a float with Kernel.Float (if <tt>only_integer</tt>
-      # is +false+) or applying it to the regular expression <tt>/\A[\+\-]?\d+\Z/</tt>
+      # is +false+) or applying it to the regular expression <tt>/\A[\+\-]?\d+\z/</tt>
       # (if <tt>only_integer</tt> is set to +true+).
       #
       #   class Person < ActiveRecord::Base
@@ -139,7 +139,7 @@ module ActiveModel
       #
       # There is also a list of default options supported by every validator:
       # +:if+, +:unless+, +:on+, +:allow_nil+, +:allow_blank+, and +:strict+ .
-      # See <tt>ActiveModel::Validation#validates</tt> for more information
+      # See <tt>ActiveModel::Validations#validates</tt> for more information
       #
       # The following checks can also be supplied with a proc or a symbol which
       # corresponds to a method:
diff --git a/activemodel/lib/active_model/validations/presence.rb b/activemodel/lib/active_model/validations/presence.rb
index 5d593274eb..8787a75afa 100644
--- a/activemodel/lib/active_model/validations/presence.rb
+++ b/activemodel/lib/active_model/validations/presence.rb
@@ -1,6 +1,6 @@
+# frozen_string_literal: true
 
 module ActiveModel
-
   module Validations
     class PresenceValidator < EachValidator # :nodoc:
       def validate_each(record, attr_name, value)
@@ -30,7 +30,7 @@ module ActiveModel
       #
       # There is also a list of default options supported by every validator:
       # +:if+, +:unless+, +:on+, +:allow_nil+, +:allow_blank+, and +:strict+.
-      # See <tt>ActiveModel::Validation#validates</tt> for more information
+      # See <tt>ActiveModel::Validations#validates</tt> for more information
       def validates_presence_of(*attr_names)
         validates_with PresenceValidator, _merge_attributes(attr_names)
       end
diff --git a/activemodel/lib/active_model/validations/validates.rb b/activemodel/lib/active_model/validations/validates.rb
index 1da4df21e7..e28e7e9219 100644
--- a/activemodel/lib/active_model/validations/validates.rb
+++ b/activemodel/lib/active_model/validations/validates.rb
@@ -1,4 +1,6 @@
-require 'active_support/core_ext/hash/slice'
+# frozen_string_literal: true
+
+require "active_support/core_ext/hash/slice"
 
 module ActiveModel
   module Validations
@@ -18,7 +20,6 @@ module ActiveModel
       #   validates :first_name, length: { maximum: 30 }
       #   validates :age, numericality: true
       #   validates :username, presence: true
-      #   validates :username, uniqueness: true
       #
       # The power of the +validates+ method comes when using custom validators
       # and default validators in one call for a given attribute.
@@ -34,7 +35,7 @@ module ActiveModel
       #     include ActiveModel::Validations
       #     attr_accessor :name, :email
       #
-      #     validates :name, presence: true, uniqueness: true, length: { maximum: 100 }
+      #     validates :name, presence: true, length: { maximum: 100 }
       #     validates :email, presence: true, email: true
       #   end
       #
@@ -72,7 +73,7 @@ module ActiveModel
       # There is also a list of options that could be used along with validators:
       #
       # * <tt>:on</tt> - Specifies the contexts where this validation is active.
-      #   Runs in all validation contexts by default (nil). You can pass a symbol
+      #   Runs in all validation contexts by default +nil+. You can pass a symbol
       #   or an array of symbols. (e.g. <tt>on: :create</tt> or
       #   <tt>on: :custom_validation_context</tt> or
       #   <tt>on: [:create, :custom_validation_context]</tt>)
@@ -94,7 +95,7 @@ module ActiveModel
       # Example:
       #
       #   validates :password, presence: true, confirmation: true, if: :password_required?
-      #   validates :token, uniqueness: true, strict: TokenGenerationException
+      #   validates :token, length: 24, strict: TokenLengthException
       #
       #
       # Finally, the options +:if+, +:unless+, +:on+, +:allow_blank+, +:allow_nil+, +:strict+
@@ -115,7 +116,7 @@ module ActiveModel
           key = "#{key.to_s.camelize}Validator"
 
           begin
-            validator = key.include?('::'.freeze) ? key.constantize : const_get(key)
+            validator = key.include?("::".freeze) ? key.constantize : const_get(key)
           rescue NameError
             raise ArgumentError, "Unknown validator: '#{key}'"
           end
@@ -148,15 +149,15 @@ module ActiveModel
         validates(*(attributes << options))
       end
 
-    protected
+    private
 
       # When creating custom validators, it might be useful to be able to specify
       # additional default keys. This can be done by overwriting this method.
-      def _validates_default_keys # :nodoc:
-        [:if, :unless, :on, :allow_blank, :allow_nil , :strict]
+      def _validates_default_keys
+        [:if, :unless, :on, :allow_blank, :allow_nil, :strict]
       end
 
-      def _parse_validates_options(options) # :nodoc:
+      def _parse_validates_options(options)
         case options
         when TrueClass
           {}
diff --git a/activemodel/lib/active_model/validations/with.rb b/activemodel/lib/active_model/validations/with.rb
index 6de01b3392..d777ac836e 100644
--- a/activemodel/lib/active_model/validations/with.rb
+++ b/activemodel/lib/active_model/validations/with.rb
@@ -1,3 +1,7 @@
+# frozen_string_literal: true
+
+require "active_support/core_ext/array/extract_options"
+
 module ActiveModel
   module Validations
     class WithValidator < EachValidator # :nodoc:
@@ -43,7 +47,7 @@ module ActiveModel
       #
       # Configuration options:
       # * <tt>:on</tt> - Specifies the contexts where this validation is active.
-      #   Runs in all validation contexts by default (nil). You can pass a symbol
+      #   Runs in all validation contexts by default +nil+. You can pass a symbol
       #   or an array of symbols. (e.g. <tt>on: :create</tt> or
       #   <tt>on: :custom_validation_context</tt> or
       #   <tt>on: [:create, :custom_validation_context]</tt>)
@@ -59,7 +63,7 @@ module ActiveModel
       #   The method, proc or string should return or evaluate to a +true+ or
       #   +false+ value.
       # * <tt>:strict</tt> - Specifies whether validation should be strict.
-      #   See <tt>ActiveModel::Validation#validates!</tt> for more information.
+      #   See <tt>ActiveModel::Validations#validates!</tt> for more information.
       #
       # If you pass any additional configuration options, they will be passed
       # to the class and available as +options+:
diff --git a/activemodel/lib/active_model/validator.rb b/activemodel/lib/active_model/validator.rb
index 699f74ed17..e17c3ca7b3 100644
--- a/activemodel/lib/active_model/validator.rb
+++ b/activemodel/lib/active_model/validator.rb
@@ -1,7 +1,8 @@
+# frozen_string_literal: true
+
 require "active_support/core_ext/module/anonymous"
 
 module ActiveModel
-
   # == Active \Model \Validator
   #
   # A simple base class that can be used along with
@@ -83,7 +84,7 @@ module ActiveModel
   #   end
   #
   # It can be useful to access the class that is using that validator when there are prerequisites such
-  # as an +attr_accessor+ being present. This class is accessible via +options[:class]+ in the constructor.
+  # as an +attr_accessor+ being present. This class is accessible via <tt>options[:class]</tt> in the constructor.
   # To setup your validator override the constructor.
   #
   #   class MyValidator < ActiveModel::Validator
@@ -98,20 +99,20 @@ module ActiveModel
     # Returns the kind of the validator.
     #
     #   PresenceValidator.kind   # => :presence
-    #   UniquenessValidator.kind # => :uniqueness
+    #   AcceptanceValidator.kind # => :acceptance
     def self.kind
-      @kind ||= name.split('::').last.underscore.chomp('_validator').to_sym unless anonymous?
+      @kind ||= name.split("::").last.underscore.chomp("_validator").to_sym unless anonymous?
     end
 
     # Accepts options that will be made available through the +options+ reader.
     def initialize(options = {})
-      @options  = options.except(:class).freeze
+      @options = options.except(:class).freeze
     end
 
     # Returns the kind for this validator.
     #
-    #   PresenceValidator.new.kind   # => :presence
-    #   UniquenessValidator.new.kind # => :uniqueness
+    #   PresenceValidator.new(attributes: [:username]).kind # => :presence
+    #   AcceptanceValidator.new(attributes: [:terms]).kind  # => :acceptance
     def kind
       self.class.kind
     end
@@ -142,8 +143,8 @@ module ActiveModel
     end
 
     # Performs validation on the supplied record. By default this will call
-    # +validates_each+ to determine validity therefore subclasses should
-    # override +validates_each+ with validation logic.
+    # +validate_each+ to determine validity therefore subclasses should
+    # override +validate_each+ with validation logic.
     def validate(record)
       attributes.each do |attribute|
         value = record.read_attribute_for_validation(attribute)
@@ -175,8 +176,8 @@ module ActiveModel
 
     private
 
-    def validate_each(record, attribute, value)
-      @block.call(record, attribute, value)
-    end
+      def validate_each(record, attribute, value)
+        @block.call(record, attribute, value)
+      end
   end
 end
diff --git a/activemodel/lib/active_model/version.rb b/activemodel/lib/active_model/version.rb
index 6da3b4117b..dd817f5639 100644
--- a/activemodel/lib/active_model/version.rb
+++ b/activemodel/lib/active_model/version.rb
@@ -1,4 +1,6 @@
-require_relative 'gem_version'
+# frozen_string_literal: true
+
+require_relative "gem_version"
 
 module ActiveModel
   # Returns the version of the currently loaded \Active \Model as a <tt>Gem::Version</tt>
diff --git a/activemodel/test/cases/attribute_assignment_test.rb b/activemodel/test/cases/attribute_assignment_test.rb
index 287bea719c..5ecf0a69c4 100644
--- a/activemodel/test/cases/attribute_assignment_test.rb
+++ b/activemodel/test/cases/attribute_assignment_test.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require "cases/helper"
 require "active_support/core_ext/hash/indifferent_access"
 require "active_support/hash_with_indifferent_access"
@@ -16,9 +18,11 @@ class AttributeAssignmentTest < ActiveModel::TestCase
       raise ErrorFromAttributeWriter
     end
 
+    # TODO Change this to private once we've dropped Ruby 2.2 support.
+    # Workaround for Ruby 2.2 "private attribute?" warning.
     protected
 
-    attr_writer :metadata
+      attr_writer :metadata
   end
 
   class ErrorFromAttributeWriter < StandardError
diff --git a/activemodel/test/cases/attribute_methods_test.rb b/activemodel/test/cases/attribute_methods_test.rb
index e81b7ac424..d2837ec894 100644
--- a/activemodel/test/cases/attribute_methods_test.rb
+++ b/activemodel/test/cases/attribute_methods_test.rb
@@ -1,16 +1,18 @@
-require 'cases/helper'
+# frozen_string_literal: true
+
+require "cases/helper"
 
 class ModelWithAttributes
   include ActiveModel::AttributeMethods
 
   class << self
     define_method(:bar) do
-      'original bar'
+      "original bar"
     end
   end
 
   def attributes
-    { foo: 'value of foo', baz: 'value of baz' }
+    { foo: "value of foo", baz: "value of baz" }
   end
 
 private
@@ -24,7 +26,7 @@ class ModelWithAttributes2
 
   attr_accessor :attributes
 
-  attribute_method_suffix '_test'
+  attribute_method_suffix "_test"
 
 private
   def attribute(name)
@@ -48,7 +50,7 @@ class ModelWithAttributesWithSpaces
   include ActiveModel::AttributeMethods
 
   def attributes
-    { :'foo bar' => 'value of foo bar'}
+    { 'foo bar': "value of foo bar" }
   end
 
 private
@@ -62,12 +64,12 @@ class ModelWithWeirdNamesAttributes
 
   class << self
     define_method(:'c?d') do
-      'original c?d'
+      "original c?d"
     end
   end
 
   def attributes
-    { :'a?b' => 'value of a?b' }
+    { 'a?b': "value of a?b" }
   end
 
 private
@@ -80,7 +82,7 @@ class ModelWithRubyKeywordNamedAttributes
   include ActiveModel::AttributeMethods
 
   def attributes
-    { begin: 'value of begin', end: 'value of end' }
+    { begin: "value of begin", end: "value of end" }
   end
 
 private
@@ -94,16 +96,16 @@ class ModelWithoutAttributesMethod
 end
 
 class AttributeMethodsTest < ActiveModel::TestCase
-  test 'method missing works correctly even if attributes method is not defined' do
+  test "method missing works correctly even if attributes method is not defined" do
     assert_raises(NoMethodError) { ModelWithoutAttributesMethod.new.foo }
   end
 
-  test 'unrelated classes should not share attribute method matchers' do
+  test "unrelated classes should not share attribute method matchers" do
     assert_not_equal ModelWithAttributes.send(:attribute_method_matchers),
                      ModelWithAttributes2.send(:attribute_method_matchers)
   end
 
-  test '#define_attribute_method generates attribute method' do
+  test "#define_attribute_method generates attribute method" do
     begin
       ModelWithAttributes.define_attribute_method(:foo)
 
@@ -114,19 +116,19 @@ class AttributeMethodsTest < ActiveModel::TestCase
     end
   end
 
-  test '#define_attribute_method does not generate attribute method if already defined in attribute module' do
+  test "#define_attribute_method does not generate attribute method if already defined in attribute module" do
     klass = Class.new(ModelWithAttributes)
-    klass.generated_attribute_methods.module_eval do
+    klass.send(:generated_attribute_methods).module_eval do
       def foo
-        '<3'
+        "<3"
       end
     end
     klass.define_attribute_method(:foo)
 
-    assert_equal '<3', klass.new.foo
+    assert_equal "<3", klass.new.foo
   end
 
-  test '#define_attribute_method generates a method that is already defined on the host' do
+  test "#define_attribute_method generates a method that is already defined on the host" do
     klass = Class.new(ModelWithAttributes) do
       def foo
         super
@@ -134,21 +136,21 @@ class AttributeMethodsTest < ActiveModel::TestCase
     end
     klass.define_attribute_method(:foo)
 
-    assert_equal 'value of foo', klass.new.foo
+    assert_equal "value of foo", klass.new.foo
   end
 
-  test '#define_attribute_method generates attribute method with invalid identifier characters' do
+  test "#define_attribute_method generates attribute method with invalid identifier characters" do
     begin
       ModelWithWeirdNamesAttributes.define_attribute_method(:'a?b')
 
       assert_respond_to ModelWithWeirdNamesAttributes.new, :'a?b'
-      assert_equal "value of a?b", ModelWithWeirdNamesAttributes.new.send('a?b')
+      assert_equal "value of a?b", ModelWithWeirdNamesAttributes.new.send("a?b")
     ensure
       ModelWithWeirdNamesAttributes.undefine_attribute_methods
     end
   end
 
-  test '#define_attribute_methods works passing multiple arguments' do
+  test "#define_attribute_methods works passing multiple arguments" do
     begin
       ModelWithAttributes.define_attribute_methods(:foo, :baz)
 
@@ -159,7 +161,7 @@ class AttributeMethodsTest < ActiveModel::TestCase
     end
   end
 
-  test '#define_attribute_methods generates attribute methods' do
+  test "#define_attribute_methods generates attribute methods" do
     begin
       ModelWithAttributes.define_attribute_methods(:foo)
 
@@ -170,7 +172,7 @@ class AttributeMethodsTest < ActiveModel::TestCase
     end
   end
 
-  test '#alias_attribute generates attribute_aliases lookup hash' do
+  test "#alias_attribute generates attribute_aliases lookup hash" do
     klass = Class.new(ModelWithAttributes) do
       define_attribute_methods :foo
       alias_attribute :bar, :foo
@@ -179,7 +181,7 @@ class AttributeMethodsTest < ActiveModel::TestCase
     assert_equal({ "bar" => "foo" }, klass.attribute_aliases)
   end
 
-  test '#define_attribute_methods generates attribute methods with spaces in their names' do
+  test "#define_attribute_methods generates attribute methods with spaces in their names" do
     begin
       ModelWithAttributesWithSpaces.define_attribute_methods(:'foo bar')
 
@@ -190,7 +192,7 @@ class AttributeMethodsTest < ActiveModel::TestCase
     end
   end
 
-  test '#alias_attribute works with attributes with spaces in their names' do
+  test "#alias_attribute works with attributes with spaces in their names" do
     begin
       ModelWithAttributesWithSpaces.define_attribute_methods(:'foo bar')
       ModelWithAttributesWithSpaces.alias_attribute(:'foo_bar', :'foo bar')
@@ -201,7 +203,7 @@ class AttributeMethodsTest < ActiveModel::TestCase
     end
   end
 
-  test '#alias_attribute works with attributes named as a ruby keyword' do
+  test "#alias_attribute works with attributes named as a ruby keyword" do
     begin
       ModelWithRubyKeywordNamedAttributes.define_attribute_methods([:begin, :end])
       ModelWithRubyKeywordNamedAttributes.alias_attribute(:from, :begin)
@@ -214,7 +216,7 @@ class AttributeMethodsTest < ActiveModel::TestCase
     end
   end
 
-  test '#undefine_attribute_methods removes attribute methods' do
+  test "#undefine_attribute_methods removes attribute methods" do
     ModelWithAttributes.define_attribute_methods(:foo)
     ModelWithAttributes.undefine_attribute_methods
 
@@ -222,21 +224,21 @@ class AttributeMethodsTest < ActiveModel::TestCase
     assert_raises(NoMethodError) { ModelWithAttributes.new.foo }
   end
 
-  test 'accessing a suffixed attribute' do
+  test "accessing a suffixed attribute" do
     m = ModelWithAttributes2.new
-    m.attributes = { 'foo' => 'bar' }
+    m.attributes = { "foo" => "bar" }
 
-    assert_equal 'bar', m.foo
-    assert_equal 'bar', m.foo_test
+    assert_equal "bar", m.foo
+    assert_equal "bar", m.foo_test
   end
 
-  test 'should not interfere with method_missing if the attr has a private/protected method' do
+  test "should not interfere with method_missing if the attr has a private/protected method" do
     m = ModelWithAttributes2.new
-    m.attributes = { 'private_method' => '<3', 'protected_method' => 'O_o' }
+    m.attributes = { "private_method" => "<3", "protected_method" => "O_o" }
 
     # dispatches to the *method*, not the attribute
-    assert_equal '<3 <3',   m.send(:private_method)
-    assert_equal 'O_o O_o', m.send(:protected_method)
+    assert_equal "<3 <3",   m.send(:private_method)
+    assert_equal "O_o O_o", m.send(:protected_method)
 
     # sees that a method is already defined, so doesn't intervene
     assert_raises(NoMethodError) { m.private_method }
@@ -245,13 +247,13 @@ class AttributeMethodsTest < ActiveModel::TestCase
 
   class ClassWithProtected
     protected
-    def protected_method
-    end
+      def protected_method
+      end
   end
 
-  test 'should not interfere with respond_to? if the attribute has a private/protected method' do
+  test "should not interfere with respond_to? if the attribute has a private/protected method" do
     m = ModelWithAttributes2.new
-    m.attributes = { 'private_method' => '<3', 'protected_method' => 'O_o' }
+    m.attributes = { "private_method" => "<3", "protected_method" => "O_o" }
 
     assert !m.respond_to?(:private_method)
     assert m.respond_to?(:private_method, true)
@@ -264,9 +266,9 @@ class AttributeMethodsTest < ActiveModel::TestCase
     assert m.respond_to?(:protected_method, true)
   end
 
-  test 'should use attribute_missing to dispatch a missing attribute' do
+  test "should use attribute_missing to dispatch a missing attribute" do
     m = ModelWithAttributes2.new
-    m.attributes = { 'foo' => 'bar' }
+    m.attributes = { "foo" => "bar" }
 
     def m.attribute_missing(match, *args, &block)
       match
@@ -274,8 +276,8 @@ class AttributeMethodsTest < ActiveModel::TestCase
 
     match = m.foo_test
 
-    assert_equal 'foo',            match.attr_name
-    assert_equal 'attribute_test', match.target
-    assert_equal 'foo_test',       match.method_name
+    assert_equal "foo",            match.attr_name
+    assert_equal "attribute_test", match.target
+    assert_equal "foo_test",       match.method_name
   end
 end
diff --git a/activerecord/test/cases/attribute_set_test.rb b/activemodel/test/cases/attribute_set_test.rb
index 7a24b85a36..6e522d6c80 100644
--- a/activerecord/test/cases/attribute_set_test.rb
+++ b/activemodel/test/cases/attribute_set_test.rb
@@ -1,10 +1,13 @@
-require 'cases/helper'
+# frozen_string_literal: true
 
-module ActiveRecord
-  class AttributeSetTest < ActiveRecord::TestCase
+require "cases/helper"
+require "active_model/attribute_set"
+
+module ActiveModel
+  class AttributeSetTest < ActiveModel::TestCase
     test "building a new set from raw attributes" do
       builder = AttributeSet::Builder.new(foo: Type::Integer.new, bar: Type::Float.new)
-      attributes = builder.build_from_database(foo: '1.1', bar: '2.2')
+      attributes = builder.build_from_database(foo: "1.1", bar: "2.2")
 
       assert_equal 1, attributes[:foo].value
       assert_equal 2.2, attributes[:bar].value
@@ -14,7 +17,7 @@ module ActiveRecord
 
     test "building with custom types" do
       builder = AttributeSet::Builder.new(foo: Type::Float.new)
-      attributes = builder.build_from_database({ foo: '3.3', bar: '4.4' }, { bar: Type::Integer.new })
+      attributes = builder.build_from_database({ foo: "3.3", bar: "4.4" }, { bar: Type::Integer.new })
 
       assert_equal 3.3, attributes[:foo].value
       assert_equal 4, attributes[:bar].value
@@ -22,16 +25,16 @@ module ActiveRecord
 
     test "[] returns a null object" do
       builder = AttributeSet::Builder.new(foo: Type::Float.new)
-      attributes = builder.build_from_database(foo: '3.3')
+      attributes = builder.build_from_database(foo: "3.3")
 
-      assert_equal '3.3', attributes[:foo].value_before_type_cast
-      assert_equal nil, attributes[:bar].value_before_type_cast
+      assert_equal "3.3", attributes[:foo].value_before_type_cast
+      assert_nil attributes[:bar].value_before_type_cast
       assert_equal :bar, attributes[:bar].name
     end
 
     test "duping creates a new hash, but does not dup the attributes" do
       builder = AttributeSet::Builder.new(foo: Type::Integer.new, bar: Type::String.new)
-      attributes = builder.build_from_database(foo: 1, bar: 'foo')
+      attributes = builder.build_from_database(foo: 1, bar: "foo")
 
       # Ensure the type cast value is cached
       attributes[:foo].value
@@ -39,17 +42,17 @@ module ActiveRecord
 
       duped = attributes.dup
       duped.write_from_database(:foo, 2)
-      duped[:bar].value << 'bar'
+      duped[:bar].value << "bar"
 
       assert_equal 1, attributes[:foo].value
       assert_equal 2, duped[:foo].value
-      assert_equal 'foobar', attributes[:bar].value
-      assert_equal 'foobar', duped[:bar].value
+      assert_equal "foobar", attributes[:bar].value
+      assert_equal "foobar", duped[:bar].value
     end
 
     test "deep_duping creates a new hash and dups each attribute" do
       builder = AttributeSet::Builder.new(foo: Type::Integer.new, bar: Type::String.new)
-      attributes = builder.build_from_database(foo: 1, bar: 'foo')
+      attributes = builder.build_from_database(foo: 1, bar: "foo")
 
       # Ensure the type cast value is cached
       attributes[:foo].value
@@ -57,12 +60,12 @@ module ActiveRecord
 
       duped = attributes.deep_dup
       duped.write_from_database(:foo, 2)
-      duped[:bar].value << 'bar'
+      duped[:bar].value << "bar"
 
       assert_equal 1, attributes[:foo].value
       assert_equal 2, duped[:foo].value
-      assert_equal 'foo', attributes[:bar].value
-      assert_equal 'foobar', duped[:bar].value
+      assert_equal "foo", attributes[:bar].value
+      assert_equal "foobar", duped[:bar].value
     end
 
     test "freezing cloned set does not freeze original" do
@@ -77,7 +80,7 @@ module ActiveRecord
 
     test "to_hash returns a hash of the type cast values" do
       builder = AttributeSet::Builder.new(foo: Type::Integer.new, bar: Type::Float.new)
-      attributes = builder.build_from_database(foo: '1.1', bar: '2.2')
+      attributes = builder.build_from_database(foo: "1.1", bar: "2.2")
 
       assert_equal({ foo: 1, bar: 2.2 }, attributes.to_hash)
       assert_equal({ foo: 1, bar: 2.2 }, attributes.to_h)
@@ -85,7 +88,7 @@ module ActiveRecord
 
     test "to_hash maintains order" do
       builder = AttributeSet::Builder.new(foo: Type::Integer.new, bar: Type::Float.new)
-      attributes = builder.build_from_database(foo: '2.2', bar: '3.3')
+      attributes = builder.build_from_database(foo: "2.2", bar: "3.3")
 
       attributes[:bar]
       hash = attributes.to_h
@@ -95,9 +98,9 @@ module ActiveRecord
 
     test "values_before_type_cast" do
       builder = AttributeSet::Builder.new(foo: Type::Integer.new, bar: Type::Integer.new)
-      attributes = builder.build_from_database(foo: '1.1', bar: '2.2')
+      attributes = builder.build_from_database(foo: "1.1", bar: "2.2")
 
-      assert_equal({ foo: '1.1', bar: '2.2' }, attributes.values_before_type_cast)
+      assert_equal({ foo: "1.1", bar: "2.2" }, attributes.values_before_type_cast)
     end
 
     test "known columns are built with uninitialized attributes" do
@@ -129,7 +132,7 @@ module ActiveRecord
 
     test "fetch_value returns the value for the given initialized attribute" do
       builder = AttributeSet::Builder.new(foo: Type::Integer.new, bar: Type::Float.new)
-      attributes = builder.build_from_database(foo: '1.1', bar: '2.2')
+      attributes = builder.build_from_database(foo: "1.1", bar: "2.2")
 
       assert_equal 1, attributes.fetch_value(:foo)
       assert_equal 2.2, attributes.fetch_value(:bar)
@@ -150,8 +153,8 @@ module ActiveRecord
 
     test "fetch_value uses the given block for uninitialized attributes" do
       attributes = attributes_with_uninitialized_key
-      value = attributes.fetch_value(:bar) { |n| n.to_s + '!' }
-      assert_equal 'bar!', value
+      value = attributes.fetch_value(:bar) { |n| n.to_s + "!" }
+      assert_equal "bar!", value
     end
 
     test "fetch_value returns nil for uninitialized attributes if no block is given" do
@@ -160,7 +163,8 @@ module ActiveRecord
     end
 
     test "the primary_key is always initialized" do
-      builder = AttributeSet::Builder.new({ foo: Type::Integer.new }, :foo)
+      defaults = { foo: Attribute.from_user(:foo, nil, nil) }
+      builder = AttributeSet::Builder.new({ foo: Type::Integer.new }, defaults)
       attributes = builder.build_from_database
 
       assert attributes.key?(:foo)
@@ -207,7 +211,7 @@ module ActiveRecord
 
     def attributes_with_uninitialized_key
       builder = AttributeSet::Builder.new(foo: Type::Integer.new, bar: Type::Float.new)
-      builder.build_from_database(foo: '1.1')
+      builder.build_from_database(foo: "1.1")
     end
 
     test "freezing doesn't prevent the set from materializing" do
diff --git a/activerecord/test/cases/attribute_test.rb b/activemodel/test/cases/attribute_test.rb
index b1b8639696..14d86cef97 100644
--- a/activerecord/test/cases/attribute_test.rb
+++ b/activemodel/test/cases/attribute_test.rb
@@ -1,7 +1,9 @@
-require 'cases/helper'
+# frozen_string_literal: true
 
-module ActiveRecord
-  class AttributeTest < ActiveRecord::TestCase
+require "cases/helper"
+
+module ActiveModel
+  class AttributeTest < ActiveModel::TestCase
     setup do
       @type = Minitest::Mock.new
     end
@@ -11,91 +13,91 @@ module ActiveRecord
     end
 
     test "from_database + read type casts from database" do
-      @type.expect(:deserialize, 'type cast from database', ['a value'])
-      attribute = Attribute.from_database(nil, 'a value', @type)
+      @type.expect(:deserialize, "type cast from database", ["a value"])
+      attribute = Attribute.from_database(nil, "a value", @type)
 
       type_cast_value = attribute.value
 
-      assert_equal 'type cast from database', type_cast_value
+      assert_equal "type cast from database", type_cast_value
     end
 
     test "from_user + read type casts from user" do
-      @type.expect(:cast, 'type cast from user', ['a value'])
-      attribute = Attribute.from_user(nil, 'a value', @type)
+      @type.expect(:cast, "type cast from user", ["a value"])
+      attribute = Attribute.from_user(nil, "a value", @type)
 
       type_cast_value = attribute.value
 
-      assert_equal 'type cast from user', type_cast_value
+      assert_equal "type cast from user", type_cast_value
     end
 
     test "reading memoizes the value" do
-      @type.expect(:deserialize, 'from the database', ['whatever'])
-      attribute = Attribute.from_database(nil, 'whatever', @type)
+      @type.expect(:deserialize, "from the database", ["whatever"])
+      attribute = Attribute.from_database(nil, "whatever", @type)
 
       type_cast_value = attribute.value
       second_read = attribute.value
 
-      assert_equal 'from the database', type_cast_value
+      assert_equal "from the database", type_cast_value
       assert_same type_cast_value, second_read
     end
 
     test "reading memoizes falsy values" do
-      @type.expect(:deserialize, false, ['whatever'])
-      attribute = Attribute.from_database(nil, 'whatever', @type)
+      @type.expect(:deserialize, false, ["whatever"])
+      attribute = Attribute.from_database(nil, "whatever", @type)
 
       attribute.value
       attribute.value
     end
 
     test "read_before_typecast returns the given value" do
-      attribute = Attribute.from_database(nil, 'raw value', @type)
+      attribute = Attribute.from_database(nil, "raw value", @type)
 
       raw_value = attribute.value_before_type_cast
 
-      assert_equal 'raw value', raw_value
+      assert_equal "raw value", raw_value
     end
 
     test "from_database + read_for_database type casts to and from database" do
-      @type.expect(:deserialize, 'read from database', ['whatever'])
-      @type.expect(:serialize, 'ready for database', ['read from database'])
-      attribute = Attribute.from_database(nil, 'whatever', @type)
+      @type.expect(:deserialize, "read from database", ["whatever"])
+      @type.expect(:serialize, "ready for database", ["read from database"])
+      attribute = Attribute.from_database(nil, "whatever", @type)
 
       serialize = attribute.value_for_database
 
-      assert_equal 'ready for database', serialize
+      assert_equal "ready for database", serialize
     end
 
     test "from_user + read_for_database type casts from the user to the database" do
-      @type.expect(:cast, 'read from user', ['whatever'])
-      @type.expect(:serialize, 'ready for database', ['read from user'])
-      attribute = Attribute.from_user(nil, 'whatever', @type)
+      @type.expect(:cast, "read from user", ["whatever"])
+      @type.expect(:serialize, "ready for database", ["read from user"])
+      attribute = Attribute.from_user(nil, "whatever", @type)
 
       serialize = attribute.value_for_database
 
-      assert_equal 'ready for database', serialize
+      assert_equal "ready for database", serialize
     end
 
     test "duping dups the value" do
-      @type.expect(:deserialize, 'type cast', ['a value'])
-      attribute = Attribute.from_database(nil, 'a value', @type)
+      @type.expect(:deserialize, "type cast".dup, ["a value"])
+      attribute = Attribute.from_database(nil, "a value", @type)
 
       value_from_orig = attribute.value
       value_from_clone = attribute.dup.value
-      value_from_orig << ' foo'
+      value_from_orig << " foo"
 
-      assert_equal 'type cast foo', value_from_orig
-      assert_equal 'type cast', value_from_clone
+      assert_equal "type cast foo", value_from_orig
+      assert_equal "type cast", value_from_clone
     end
 
     test "duping does not dup the value if it is not dupable" do
-      @type.expect(:deserialize, false, ['a value'])
-      attribute = Attribute.from_database(nil, 'a value', @type)
+      @type.expect(:deserialize, false, ["a value"])
+      attribute = Attribute.from_database(nil, "a value", @type)
 
       assert_same attribute.value, attribute.dup.value
     end
 
     test "duping does not eagerly type cast if we have not yet type cast" do
-      attribute = Attribute.from_database(nil, 'a value', @type)
+      attribute = Attribute.from_database(nil, "a value", @type)
       attribute.dup
     end
 
@@ -244,7 +246,7 @@ module ActiveRecord
     end
 
     test "with_type preserves mutations" do
-      attribute = Attribute.from_database(:foo, "", Type::Value.new)
+      attribute = Attribute.from_database(:foo, "".dup, Type::Value.new)
       attribute.value << "1"
 
       assert_equal 1, attribute.with_type(Type::Integer.new).value
diff --git a/activemodel/test/cases/attributes_dirty_test.rb b/activemodel/test/cases/attributes_dirty_test.rb
new file mode 100644
index 0000000000..83a86371e0
--- /dev/null
+++ b/activemodel/test/cases/attributes_dirty_test.rb
@@ -0,0 +1,205 @@
+# frozen_string_literal: true
+
+require "cases/helper"
+
+class AttributesDirtyTest < ActiveModel::TestCase
+  class DirtyModel
+    include ActiveModel::Model
+    include ActiveModel::Attributes
+    include ActiveModel::Dirty
+    attribute :name, :string
+    attribute :color, :string
+    attribute :size, :integer
+
+    def save
+      changes_applied
+    end
+
+    def reload
+      clear_changes_information
+    end
+  end
+
+  setup do
+    @model = DirtyModel.new
+  end
+
+  test "setting attribute will result in change" do
+    assert !@model.changed?
+    assert !@model.name_changed?
+    @model.name = "Ringo"
+    assert @model.changed?
+    assert @model.name_changed?
+  end
+
+  test "list of changed attribute keys" do
+    assert_equal [], @model.changed
+    @model.name = "Paul"
+    assert_equal ["name"], @model.changed
+  end
+
+  test "changes to attribute values" do
+    assert !@model.changes["name"]
+    @model.name = "John"
+    assert_equal [nil, "John"], @model.changes["name"]
+  end
+
+  test "checking if an attribute has changed to a particular value" do
+    @model.name = "Ringo"
+    assert @model.name_changed?(from: nil, to: "Ringo")
+    assert_not @model.name_changed?(from: "Pete", to: "Ringo")
+    assert @model.name_changed?(to: "Ringo")
+    assert_not @model.name_changed?(to: "Pete")
+    assert @model.name_changed?(from: nil)
+    assert_not @model.name_changed?(from: "Pete")
+  end
+
+  test "changes accessible through both strings and symbols" do
+    @model.name = "David"
+    assert_not_nil @model.changes[:name]
+    assert_not_nil @model.changes["name"]
+  end
+
+  test "be consistent with symbols arguments after the changes are applied" do
+    @model.name = "David"
+    assert @model.attribute_changed?(:name)
+    @model.save
+    @model.name = "Rafael"
+    assert @model.attribute_changed?(:name)
+  end
+
+  test "attribute mutation" do
+    @model.name = "Yam"
+    @model.save
+    assert !@model.name_changed?
+    @model.name.replace("Hadad")
+    assert @model.name_changed?
+  end
+
+  test "resetting attribute" do
+    @model.name = "Bob"
+    @model.restore_name!
+    assert_nil @model.name
+    assert !@model.name_changed?
+  end
+
+  test "setting color to same value should not result in change being recorded" do
+    @model.color = "red"
+    assert @model.color_changed?
+    @model.save
+    assert !@model.color_changed?
+    assert !@model.changed?
+    @model.color = "red"
+    assert !@model.color_changed?
+    assert !@model.changed?
+  end
+
+  test "saving should reset model's changed status" do
+    @model.name = "Alf"
+    assert @model.changed?
+    @model.save
+    assert !@model.changed?
+    assert !@model.name_changed?
+  end
+
+  test "saving should preserve previous changes" do
+    @model.name = "Jericho Cane"
+    @model.save
+    assert_equal [nil, "Jericho Cane"], @model.previous_changes["name"]
+  end
+
+  test "setting new attributes should not affect previous changes" do
+    @model.name = "Jericho Cane"
+    @model.save
+    @model.name = "DudeFella ManGuy"
+    assert_equal [nil, "Jericho Cane"], @model.name_previous_change
+  end
+
+  test "saving should preserve model's previous changed status" do
+    @model.name = "Jericho Cane"
+    @model.save
+    assert @model.name_previously_changed?
+  end
+
+  test "previous value is preserved when changed after save" do
+    assert_equal({}, @model.changed_attributes)
+    @model.name = "Paul"
+    assert_equal({ "name" => nil }, @model.changed_attributes)
+
+    @model.save
+
+    @model.name = "John"
+    assert_equal({ "name" => "Paul" }, @model.changed_attributes)
+  end
+
+  test "changing the same attribute multiple times retains the correct original value" do
+    @model.name = "Otto"
+    @model.save
+    @model.name = "DudeFella ManGuy"
+    @model.name = "Mr. Manfredgensonton"
+    assert_equal ["Otto", "Mr. Manfredgensonton"], @model.name_change
+    assert_equal @model.name_was, "Otto"
+  end
+
+  test "using attribute_will_change! with a symbol" do
+    @model.size = 1
+    assert @model.size_changed?
+  end
+
+  test "reload should reset all changes" do
+    @model.name = "Dmitry"
+    @model.name_changed?
+    @model.save
+    @model.name = "Bob"
+
+    assert_equal [nil, "Dmitry"], @model.previous_changes["name"]
+    assert_equal "Dmitry", @model.changed_attributes["name"]
+
+    @model.reload
+
+    assert_equal ActiveSupport::HashWithIndifferentAccess.new, @model.previous_changes
+    assert_equal ActiveSupport::HashWithIndifferentAccess.new, @model.changed_attributes
+  end
+
+  test "restore_attributes should restore all previous data" do
+    @model.name = "Dmitry"
+    @model.color = "Red"
+    @model.save
+    @model.name = "Bob"
+    @model.color = "White"
+
+    @model.restore_attributes
+
+    assert_not @model.changed?
+    assert_equal "Dmitry", @model.name
+    assert_equal "Red", @model.color
+  end
+
+  test "restore_attributes can restore only some attributes" do
+    @model.name = "Dmitry"
+    @model.color = "Red"
+    @model.save
+    @model.name = "Bob"
+    @model.color = "White"
+
+    @model.restore_attributes(["name"])
+
+    assert @model.changed?
+    assert_equal "Dmitry", @model.name
+    assert_equal "White", @model.color
+  end
+
+  test "changing the attribute reports a change only when the cast value changes" do
+    @model.size = "2.3"
+    @model.save
+    @model.size = "2.1"
+
+    assert_equal false, @model.changed?
+
+    @model.size = "5.1"
+
+    assert_equal true, @model.changed?
+    assert_equal true, @model.size_changed?
+    assert_equal({ "size" => [2, 5] }, @model.changes)
+  end
+end
diff --git a/activemodel/test/cases/attributes_test.rb b/activemodel/test/cases/attributes_test.rb
new file mode 100644
index 0000000000..e43bf15335
--- /dev/null
+++ b/activemodel/test/cases/attributes_test.rb
@@ -0,0 +1,68 @@
+# frozen_string_literal: true
+
+require "cases/helper"
+
+module ActiveModel
+  class AttributesTest < ActiveModel::TestCase
+    class ModelForAttributesTest
+      include ActiveModel::Model
+      include ActiveModel::Attributes
+
+      attribute :integer_field, :integer
+      attribute :string_field, :string
+      attribute :decimal_field, :decimal
+      attribute :string_with_default, :string, default: "default string"
+      attribute :date_field, :date, default: -> { Date.new(2016, 1, 1) }
+      attribute :boolean_field, :boolean
+    end
+
+    class ChildModelForAttributesTest < ModelForAttributesTest
+    end
+
+    class GrandchildModelForAttributesTest < ChildModelForAttributesTest
+      attribute :integer_field, :string
+    end
+
+    test "properties assignment" do
+      data = ModelForAttributesTest.new(
+        integer_field: "2.3",
+        string_field: "Rails FTW",
+        decimal_field: "12.3",
+        boolean_field: "0"
+      )
+
+      assert_equal 2, data.integer_field
+      assert_equal "Rails FTW", data.string_field
+      assert_equal BigDecimal("12.3"), data.decimal_field
+      assert_equal "default string", data.string_with_default
+      assert_equal Date.new(2016, 1, 1), data.date_field
+      assert_equal false, data.boolean_field
+
+      data.integer_field = 10
+      data.string_with_default = nil
+      data.boolean_field = "1"
+
+      assert_equal 10, data.integer_field
+      assert_nil data.string_with_default
+      assert_equal true, data.boolean_field
+    end
+
+    test "nonexistent attribute" do
+      assert_raise ActiveModel::UnknownAttributeError do
+        ModelForAttributesTest.new(nonexistent: "nonexistent")
+      end
+    end
+
+    test "children inherit attributes" do
+      data = ChildModelForAttributesTest.new(integer_field: "4.4")
+
+      assert_equal 4, data.integer_field
+    end
+
+    test "children can override parents" do
+      data = GrandchildModelForAttributesTest.new(integer_field: "4.4")
+
+      assert_equal "4.4", data.integer_field
+    end
+  end
+end
diff --git a/activemodel/test/cases/callbacks_test.rb b/activemodel/test/cases/callbacks_test.rb
index e4ecc0adb4..a5d29d0f22 100644
--- a/activemodel/test/cases/callbacks_test.rb
+++ b/activemodel/test/cases/callbacks_test.rb
@@ -1,7 +1,8 @@
+# frozen_string_literal: true
+
 require "cases/helper"
 
 class CallbacksTest < ActiveModel::TestCase
-
   class CallbackValidator
     def around_create(model)
       model.callbacks << :before_around_create
@@ -28,7 +29,7 @@ class CallbacksTest < ActiveModel::TestCase
       false
     end
 
-    ActiveSupport::Deprecation.silence { after_create "@callbacks << :final_callback" }
+    after_create { |model| model.callbacks << :final_callback }
 
     def initialize(options = {})
       @callbacks = []
@@ -64,12 +65,10 @@ class CallbacksTest < ActiveModel::TestCase
     assert_equal model.callbacks.last, :final_callback
   end
 
-  test "the callback chain is halted when a before callback returns false (deprecated)" do
+  test "the callback chain is not halted when a before callback returns false)" do
     model = ModelCallbacks.new(before_create_returns: false)
-    assert_deprecated do
-      model.create
-      assert_equal model.callbacks.last, :before_create
-    end
+    model.create
+    assert_equal model.callbacks.last, :final_callback
   end
 
   test "the callback chain is halted when a callback throws :abort" do
@@ -110,8 +109,8 @@ class CallbacksTest < ActiveModel::TestCase
     end
     extend ActiveModel::Callbacks
     define_model_callbacks :create
-    def callback1; self.history << 'callback1'; end
-    def callback2; self.history << 'callback2'; end
+    def callback1; history << "callback1"; end
+    def callback2; history << "callback2"; end
     def create
       run_callbacks(:create) {}
       self
@@ -128,8 +127,8 @@ class CallbacksTest < ActiveModel::TestCase
   test "after_create callbacks with both callbacks declared in one line" do
     assert_equal ["callback1", "callback2"], Violin1.new.create.history
   end
+
   test "after_create callbacks with both callbacks declared in different lines" do
     assert_equal ["callback1", "callback2"], Violin2.new.create.history
   end
-
 end
diff --git a/activemodel/test/cases/conversion_test.rb b/activemodel/test/cases/conversion_test.rb
index 800cad6d9a..347896ed50 100644
--- a/activemodel/test/cases/conversion_test.rb
+++ b/activemodel/test/cases/conversion_test.rb
@@ -1,6 +1,8 @@
-require 'cases/helper'
-require 'models/contact'
-require 'models/helicopter'
+# frozen_string_literal: true
+
+require "cases/helper"
+require "models/contact"
+require "models/helicopter"
 
 class ConversionTest < ActiveModel::TestCase
   test "to_model default implementation returns self" do
diff --git a/activemodel/test/cases/dirty_test.rb b/activemodel/test/cases/dirty_test.rb
index d17a12ad12..dfe041ff50 100644
--- a/activemodel/test/cases/dirty_test.rb
+++ b/activemodel/test/cases/dirty_test.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require "cases/helper"
 
 class DirtyTest < ActiveModel::TestCase
@@ -62,13 +64,13 @@ class DirtyTest < ActiveModel::TestCase
   test "list of changed attribute keys" do
     assert_equal [], @model.changed
     @model.name = "Paul"
-    assert_equal ['name'], @model.changed
+    assert_equal ["name"], @model.changed
   end
 
   test "changes to attribute values" do
-    assert !@model.changes['name']
+    assert !@model.changes["name"]
     @model.name = "John"
-    assert_equal [nil, "John"], @model.changes['name']
+    assert_equal [nil, "John"], @model.changes["name"]
   end
 
   test "checking if an attribute has changed to a particular value" do
@@ -84,19 +86,19 @@ class DirtyTest < ActiveModel::TestCase
   test "changes accessible through both strings and symbols" do
     @model.name = "David"
     assert_not_nil @model.changes[:name]
-    assert_not_nil @model.changes['name']
+    assert_not_nil @model.changes["name"]
   end
 
   test "be consistent with symbols arguments after the changes are applied" do
     @model.name = "David"
     assert @model.attribute_changed?(:name)
     @model.save
-    @model.name = 'Rafael'
+    @model.name = "Rafael"
     assert @model.attribute_changed?(:name)
   end
 
   test "attribute mutation" do
-    @model.instance_variable_set("@name", "Yam")
+    @model.instance_variable_set("@name", "Yam".dup)
     assert !@model.name_changed?
     @model.name.replace("Hadad")
     assert !@model.name_changed?
@@ -134,7 +136,7 @@ class DirtyTest < ActiveModel::TestCase
   test "saving should preserve previous changes" do
     @model.name = "Jericho Cane"
     @model.save
-    assert_equal [nil, "Jericho Cane"], @model.previous_changes['name']
+    assert_equal [nil, "Jericho Cane"], @model.previous_changes["name"]
   end
 
   test "setting new attributes should not affect previous changes" do
@@ -176,13 +178,13 @@ class DirtyTest < ActiveModel::TestCase
   end
 
   test "reload should reset all changes" do
-    @model.name = 'Dmitry'
+    @model.name = "Dmitry"
     @model.name_changed?
     @model.save
-    @model.name = 'Bob'
+    @model.name = "Bob"
 
-    assert_equal [nil, 'Dmitry'], @model.previous_changes['name']
-    assert_equal 'Dmitry', @model.changed_attributes['name']
+    assert_equal [nil, "Dmitry"], @model.previous_changes["name"]
+    assert_equal "Dmitry", @model.changed_attributes["name"]
 
     @model.reload
 
@@ -191,30 +193,34 @@ class DirtyTest < ActiveModel::TestCase
   end
 
   test "restore_attributes should restore all previous data" do
-    @model.name = 'Dmitry'
-    @model.color = 'Red'
+    @model.name = "Dmitry"
+    @model.color = "Red"
     @model.save
-    @model.name = 'Bob'
-    @model.color = 'White'
+    @model.name = "Bob"
+    @model.color = "White"
 
     @model.restore_attributes
 
     assert_not @model.changed?
-    assert_equal 'Dmitry', @model.name
-    assert_equal 'Red', @model.color
+    assert_equal "Dmitry", @model.name
+    assert_equal "Red", @model.color
   end
 
   test "restore_attributes can restore only some attributes" do
-    @model.name = 'Dmitry'
-    @model.color = 'Red'
+    @model.name = "Dmitry"
+    @model.color = "Red"
     @model.save
-    @model.name = 'Bob'
-    @model.color = 'White'
+    @model.name = "Bob"
+    @model.color = "White"
 
-    @model.restore_attributes(['name'])
+    @model.restore_attributes(["name"])
 
     assert @model.changed?
-    assert_equal 'Dmitry', @model.name
-    assert_equal 'White', @model.color
+    assert_equal "Dmitry", @model.name
+    assert_equal "White", @model.color
+  end
+
+  test "model can be dup-ed without Attributes" do
+    assert @model.dup
   end
 end
diff --git a/activemodel/test/cases/errors_test.rb b/activemodel/test/cases/errors_test.rb
index c90ee7021c..d5c282b620 100644
--- a/activemodel/test/cases/errors_test.rb
+++ b/activemodel/test/cases/errors_test.rb
@@ -1,4 +1,8 @@
+# frozen_string_literal: true
+
 require "cases/helper"
+require "active_support/core_ext/string/strip"
+require "yaml"
 
 class ErrorsTest < ActiveModel::TestCase
   class Person
@@ -29,45 +33,48 @@ class ErrorsTest < ActiveModel::TestCase
 
   def test_delete
     errors = ActiveModel::Errors.new(self)
-    errors[:foo] << 'omg'
-    errors.delete(:foo)
+    errors[:foo] << "omg"
+    errors.delete("foo")
     assert_empty errors[:foo]
   end
 
   def test_include?
     errors = ActiveModel::Errors.new(self)
-    errors[:foo] << 'omg'
-    assert errors.include?(:foo), 'errors should include :foo'
+    errors[:foo] << "omg"
+    assert_includes errors, :foo, "errors should include :foo"
+    assert_includes errors, "foo", "errors should include 'foo' as :foo"
   end
 
   def test_dup
     errors = ActiveModel::Errors.new(self)
-    errors[:foo] << 'bar'
+    errors[:foo] << "bar"
     errors_dup = errors.dup
-    errors_dup[:bar] << 'omg'
+    errors_dup[:bar] << "omg"
     assert_not_same errors_dup.messages, errors.messages
   end
 
   def test_has_key?
     errors = ActiveModel::Errors.new(self)
-    errors[:foo] << 'omg'
-    assert_equal true, errors.has_key?(:foo), 'errors should have key :foo'
+    errors[:foo] << "omg"
+    assert_equal true, errors.has_key?(:foo), "errors should have key :foo"
+    assert_equal true, errors.has_key?("foo"), "errors should have key 'foo' as :foo"
   end
 
   def test_has_no_key
     errors = ActiveModel::Errors.new(self)
-    assert_equal false, errors.has_key?(:name), 'errors should not have key :name'
+    assert_equal false, errors.has_key?(:name), "errors should not have key :name"
   end
 
   def test_key?
     errors = ActiveModel::Errors.new(self)
-    errors[:foo] << 'omg'
-    assert_equal true, errors.key?(:foo), 'errors should have key :foo'
+    errors[:foo] << "omg"
+    assert_equal true, errors.key?(:foo), "errors should have key :foo"
+    assert_equal true, errors.key?("foo"), "errors should have key 'foo' as :foo"
   end
 
   def test_no_key
     errors = ActiveModel::Errors.new(self)
-    assert_equal false, errors.key?(:name), 'errors should not have key :name'
+    assert_equal false, errors.key?(:name), "errors should not have key :name"
   end
 
   test "clear errors" do
@@ -79,24 +86,6 @@ class ErrorsTest < ActiveModel::TestCase
     assert person.errors.empty?
   end
 
-  test "get returns the errors for the provided key" do
-    errors = ActiveModel::Errors.new(self)
-    errors[:foo] << "omg"
-
-    assert_deprecated do
-      assert_equal ["omg"], errors.get(:foo)
-    end
-  end
-
-  test "sets the error with the provided key" do
-    errors = ActiveModel::Errors.new(self)
-    assert_deprecated do
-      errors.set(:foo, "omg")
-    end
-
-    assert_equal({ foo: "omg" }, errors.messages)
-  end
-
   test "error access is indifferent" do
     errors = ActiveModel::Errors.new(self)
     errors[:foo] << "omg"
@@ -112,6 +101,14 @@ class ErrorsTest < ActiveModel::TestCase
     assert_equal ["omg", "zomg"], errors.values
   end
 
+  test "values returns an empty array after try to get a message only" do
+    errors = ActiveModel::Errors.new(self)
+    errors.messages[:foo]
+    errors.messages[:baz]
+
+    assert_equal [], errors.values
+  end
+
   test "keys returns the error keys" do
     errors = ActiveModel::Errors.new(self)
     errors.messages[:foo] << "omg"
@@ -120,12 +117,20 @@ class ErrorsTest < ActiveModel::TestCase
     assert_equal [:foo, :baz], errors.keys
   end
 
+  test "keys returns an empty array after try to get a message only" do
+    errors = ActiveModel::Errors.new(self)
+    errors.messages[:foo]
+    errors.messages[:baz]
+
+    assert_equal [], errors.keys
+  end
+
   test "detecting whether there are errors with empty?, blank?, include?" do
     person = Person.new
     person.errors[:foo]
     assert person.errors.empty?
     assert person.errors.blank?
-    assert !person.errors.include?(:foo)
+    assert_not_includes person.errors, :foo
   end
 
   test "include? does not add a key to messages hash" do
@@ -142,14 +147,6 @@ class ErrorsTest < ActiveModel::TestCase
     assert_equal ["cannot be nil"], person.errors[:name]
   end
 
-  test "assign error" do
-    person = Person.new
-    assert_deprecated do
-      person.errors[:name] = 'should not be nil'
-    end
-    assert_equal ["should not be nil"], person.errors[:name]
-  end
-
   test "add an error message on a specific attribute" do
     person = Person.new
     person.errors.add(:name, "cannot be blank")
@@ -176,10 +173,11 @@ class ErrorsTest < ActiveModel::TestCase
     assert_equal ["cannot be blank"], person.errors[:name]
   end
 
-  test "added? detects if a specific error was added to the object" do
+  test "added? detects indifferent if a specific error was added to the object" do
     person = Person.new
     person.errors.add(:name, "cannot be blank")
     assert person.errors.added?(:name, "cannot be blank")
+    assert person.errors.added?("name", "cannot be blank")
   end
 
   test "added? handles symbol message" do
@@ -219,6 +217,19 @@ class ErrorsTest < ActiveModel::TestCase
     assert !person.errors.added?(:name, "cannot be blank")
   end
 
+  test "added? returns false when checking for an error, but not providing message arguments" do
+    person = Person.new
+    person.errors.add(:name, "cannot be blank")
+    assert !person.errors.added?(:name)
+  end
+
+  test "added? returns false when checking for an error by symbol and a different error with same message is present" do
+    I18n.backend.store_translations("en", errors: { attributes: { name: { wrong: "is wrong", used: "is wrong" } } })
+    person = Person.new
+    person.errors.add(:name, :wrong)
+    assert !person.errors.added?(:name, :used)
+  end
+
   test "size calculates the number of error messages" do
     person = Person.new
     person.errors.add(:name, "cannot be blank")
@@ -244,6 +255,16 @@ class ErrorsTest < ActiveModel::TestCase
     assert_equal({ name: ["cannot be blank"] }, person.errors.to_hash)
   end
 
+  test "to_hash returns a hash without default proc" do
+    person = Person.new
+    assert_nil person.errors.to_hash.default_proc
+  end
+
+  test "as_json returns a hash without default proc" do
+    person = Person.new
+    assert_nil person.errors.as_json.default_proc
+  end
+
   test "full_messages creates a list of error messages with the attribute name included" do
     person = Person.new
     person.errors.add(:name, "cannot be blank")
@@ -251,7 +272,7 @@ class ErrorsTest < ActiveModel::TestCase
     assert_equal ["name cannot be blank", "name cannot be nil"], person.errors.full_messages
   end
 
-  test "full_messages_for contains all the error messages for the given attribute" do
+  test "full_messages_for contains all the error messages for the given attribute indifferent" do
     person = Person.new
     person.errors.add(:name, "cannot be blank")
     person.errors.add(:name, "cannot be nil")
@@ -263,6 +284,7 @@ class ErrorsTest < ActiveModel::TestCase
     person.errors.add(:name, "cannot be blank")
     person.errors.add(:email, "cannot be blank")
     assert_equal ["name cannot be blank"], person.errors.full_messages_for(:name)
+    assert_equal ["name cannot be blank"], person.errors.full_messages_for("name")
   end
 
   test "full_messages_for returns an empty list in case there are no errors for the given attribute" do
@@ -304,72 +326,6 @@ class ErrorsTest < ActiveModel::TestCase
     }
   end
 
-  test "add_on_empty generates message" do
-    person = Person.new
-    assert_called_with(person.errors, :generate_message, [:name, :empty, {}]) do
-      assert_deprecated do
-        person.errors.add_on_empty :name
-      end
-    end
-  end
-
-  test "add_on_empty generates message for multiple attributes" do
-    person = Person.new
-    expected_calls = [ [:name, :empty, {}], [:age, :empty, {}] ]
-    assert_called_with(person.errors, :generate_message, expected_calls) do
-      assert_deprecated do
-        person.errors.add_on_empty [:name, :age]
-      end
-    end
-  end
-
-  test "add_on_empty generates message with custom default message" do
-    person = Person.new
-    assert_called_with(person.errors, :generate_message, [:name, :empty, { message: 'custom' }]) do
-      assert_deprecated do
-        person.errors.add_on_empty :name, message: 'custom'
-      end
-    end
-  end
-
-  test "add_on_empty generates message with empty string value" do
-    person = Person.new
-    person.name = ''
-    assert_called_with(person.errors, :generate_message, [:name, :empty, {}]) do
-      assert_deprecated do
-        person.errors.add_on_empty :name
-      end
-    end
-  end
-
-  test "add_on_blank generates message" do
-    person = Person.new
-    assert_called_with(person.errors, :generate_message, [:name, :blank, {}]) do
-      assert_deprecated do
-        person.errors.add_on_blank :name
-      end
-    end
-  end
-
-  test "add_on_blank generates message for multiple attributes" do
-    person = Person.new
-    expected_calls = [ [:name, :blank, {}], [:age, :blank, {}] ]
-    assert_called_with(person.errors, :generate_message, expected_calls) do
-      assert_deprecated do
-        person.errors.add_on_blank [:name, :age]
-      end
-    end
-  end
-
-  test "add_on_blank generates message with custom default message" do
-    person = Person.new
-    assert_called_with(person.errors, :generate_message, [:name, :blank, { message: 'custom' }]) do
-      assert_deprecated do
-        person.errors.add_on_blank :name, message: 'custom'
-      end
-    end
-  end
-
   test "details returns added error detail" do
     person = Person.new
     person.errors.add(:name, :invalid)
@@ -428,6 +384,18 @@ class ErrorsTest < ActiveModel::TestCase
     assert_equal [:name], person.errors.details.keys
   end
 
+  test "merge errors" do
+    errors = ActiveModel::Errors.new(Person.new)
+    errors.add(:name, :invalid)
+
+    person = Person.new
+    person.errors.add(:name, :blank)
+    person.errors.merge!(errors)
+
+    assert_equal({ name: ["can't be blank", "is invalid"] }, person.errors.messages)
+    assert_equal({ name: [{ error: :blank }, { error: :invalid }] }, person.errors.details)
+  end
+
   test "errors are marshalable" do
     errors = ActiveModel::Errors.new(Person.new)
     errors.add(:name, :invalid)
@@ -436,4 +404,24 @@ class ErrorsTest < ActiveModel::TestCase
     assert_equal errors.messages, serialized.messages
     assert_equal errors.details, serialized.details
   end
+
+  test "errors are backward compatible with the Rails 4.2 format" do
+    yaml = <<-CODE.strip_heredoc
+    --- !ruby/object:ActiveModel::Errors
+    base: &1 !ruby/object:ErrorsTest::Person
+      errors: !ruby/object:ActiveModel::Errors
+        base: *1
+        messages: {}
+    messages: {}
+    CODE
+
+    errors = YAML.load(yaml)
+    errors.add(:name, :invalid)
+    assert_equal({ name: ["is invalid"] }, errors.messages)
+    assert_equal({ name: [{ error: :invalid }] }, errors.details)
+
+    errors.clear
+    assert_equal({}, errors.messages)
+    assert_equal({}, errors.details)
+  end
 end
diff --git a/activemodel/test/cases/forbidden_attributes_protection_test.rb b/activemodel/test/cases/forbidden_attributes_protection_test.rb
index d8d757f52a..0fd0a2f8ee 100644
--- a/activemodel/test/cases/forbidden_attributes_protection_test.rb
+++ b/activemodel/test/cases/forbidden_attributes_protection_test.rb
@@ -1,6 +1,8 @@
-require 'cases/helper'
-require 'active_support/core_ext/hash/indifferent_access'
-require 'models/account'
+# frozen_string_literal: true
+
+require "cases/helper"
+require "active_support/core_ext/hash/indifferent_access"
+require "models/account"
 
 class ProtectedParams
   attr_accessor :permitted
@@ -25,18 +27,18 @@ end
 
 class ActiveModelMassUpdateProtectionTest < ActiveSupport::TestCase
   test "forbidden attributes cannot be used for mass updating" do
-    params = ProtectedParams.new({ "a" => "b" })
+    params = ProtectedParams.new("a" => "b")
     assert_raises(ActiveModel::ForbiddenAttributesError) do
       Account.new.sanitize_for_mass_assignment(params)
     end
   end
 
   test "permitted attributes can be used for mass updating" do
-    params = ProtectedParams.new({ "a" => "b" }).permit!
+    params = ProtectedParams.new("a" => "b").permit!
     assert_equal({ "a" => "b" }, Account.new.sanitize_for_mass_assignment(params))
   end
 
   test "regular attributes should still be allowed" do
-     assert_equal({ a: "b" }, Account.new.sanitize_for_mass_assignment(a: "b"))
+    assert_equal({ a: "b" }, Account.new.sanitize_for_mass_assignment(a: "b"))
   end
 end
diff --git a/activemodel/test/cases/helper.rb b/activemodel/test/cases/helper.rb
index c589fd2c33..91fb9d0a7c 100644
--- a/activemodel/test/cases/helper.rb
+++ b/activemodel/test/cases/helper.rb
@@ -1,4 +1,6 @@
-require 'active_model'
+# frozen_string_literal: true
+
+require "active_model"
 
 # Show backtraces for deprecated behavior for quicker cleanup.
 ActiveSupport::Deprecation.debug = true
@@ -6,18 +8,18 @@ ActiveSupport::Deprecation.debug = true
 # Disable available locale checks to avoid warnings running the test suite.
 I18n.enforce_available_locales = false
 
-require 'active_support/testing/autorun'
-require 'active_support/testing/method_call_assertions'
+require "active_support/testing/autorun"
+require "active_support/testing/method_call_assertions"
 
-# Skips the current run on Rubinius using Minitest::Assertions#skip
-def rubinius_skip(message = '')
-  skip message if RUBY_ENGINE == 'rbx'
-end
-# Skips the current run on JRuby using Minitest::Assertions#skip
-def jruby_skip(message = '')
-  skip message if defined?(JRUBY_VERSION)
-end
-
-class ActiveModel::TestCase
+class ActiveModel::TestCase < ActiveSupport::TestCase
   include ActiveSupport::Testing::MethodCallAssertions
+
+  # Skips the current run on Rubinius using Minitest::Assertions#skip
+  private def rubinius_skip(message = "")
+    skip message if RUBY_ENGINE == "rbx"
+  end
+  # Skips the current run on JRuby using Minitest::Assertions#skip
+  private def jruby_skip(message = "")
+    skip message if defined?(JRUBY_VERSION)
+  end
 end
diff --git a/activemodel/test/cases/lint_test.rb b/activemodel/test/cases/lint_test.rb
index 8faf93c056..d62c80b71a 100644
--- a/activemodel/test/cases/lint_test.rb
+++ b/activemodel/test/cases/lint_test.rb
@@ -1,4 +1,6 @@
-require 'cases/helper'
+# frozen_string_literal: true
+
+require "cases/helper"
 
 class LintTest < ActiveModel::TestCase
   include ActiveModel::Lint::Tests
diff --git a/activemodel/test/cases/model_test.rb b/activemodel/test/cases/model_test.rb
index 3017f3541b..b24d7e3571 100644
--- a/activemodel/test/cases/model_test.rb
+++ b/activemodel/test/cases/model_test.rb
@@ -1,4 +1,6 @@
-require 'cases/helper'
+# frozen_string_literal: true
+
+require "cases/helper"
 
 class ModelTest < ActiveModel::TestCase
   include ActiveModel::Lint::Tests
@@ -9,7 +11,7 @@ class ModelTest < ActiveModel::TestCase
     end
 
     def initialize(*args)
-      @attr ||= 'default value'
+      @attr ||= "default value"
       super
     end
   end
@@ -50,7 +52,7 @@ class ModelTest < ActiveModel::TestCase
       BasicModel.new()
       BasicModel.new(nil)
       BasicModel.new({})
-      SimpleModel.new(attr: 'value')
+      SimpleModel.new(attr: "value")
     end
   end
 
@@ -61,17 +63,17 @@ class ModelTest < ActiveModel::TestCase
 
   def test_mixin_inclusion_chain
     object = BasicModel.new
-    assert_equal 'default value', object.attr
+    assert_equal "default value", object.attr
   end
 
   def test_mixin_initializer_when_args_exist
-    object = BasicModel.new(hello: 'world')
-    assert_equal 'world', object.hello
+    object = BasicModel.new(hello: "world")
+    assert_equal "world", object.hello
   end
 
   def test_mixin_initializer_when_args_dont_exist
     assert_raises(ActiveModel::UnknownAttributeError) do
-      SimpleModel.new(hello: 'world')
+      SimpleModel.new(hello: "world")
     end
   end
 end
diff --git a/activemodel/test/cases/naming_test.rb b/activemodel/test/cases/naming_test.rb
index 7b8287edbf..009f1f47af 100644
--- a/activemodel/test/cases/naming_test.rb
+++ b/activemodel/test/cases/naming_test.rb
@@ -1,8 +1,10 @@
-require 'cases/helper'
-require 'models/contact'
-require 'models/sheep'
-require 'models/track_back'
-require 'models/blog_post'
+# frozen_string_literal: true
+
+require "cases/helper"
+require "models/contact"
+require "models/sheep"
+require "models/track_back"
+require "models/blog_post"
 
 class NamingTest < ActiveModel::TestCase
   def setup
@@ -10,31 +12,31 @@ class NamingTest < ActiveModel::TestCase
   end
 
   def test_singular
-    assert_equal 'post_track_back', @model_name.singular
+    assert_equal "post_track_back", @model_name.singular
   end
 
   def test_plural
-    assert_equal 'post_track_backs', @model_name.plural
+    assert_equal "post_track_backs", @model_name.plural
   end
 
   def test_element
-    assert_equal 'track_back', @model_name.element
+    assert_equal "track_back", @model_name.element
   end
 
   def test_collection
-    assert_equal 'post/track_backs', @model_name.collection
+    assert_equal "post/track_backs", @model_name.collection
   end
 
   def test_human
-    assert_equal 'Track back', @model_name.human
+    assert_equal "Track back", @model_name.human
   end
 
   def test_route_key
-    assert_equal 'post_track_backs', @model_name.route_key
+    assert_equal "post_track_backs", @model_name.route_key
   end
 
   def test_param_key
-    assert_equal 'post_track_back', @model_name.param_key
+    assert_equal "post_track_back", @model_name.param_key
   end
 
   def test_i18n_key
@@ -48,31 +50,31 @@ class NamingWithNamespacedModelInIsolatedNamespaceTest < ActiveModel::TestCase
   end
 
   def test_singular
-    assert_equal 'blog_post', @model_name.singular
+    assert_equal "blog_post", @model_name.singular
   end
 
   def test_plural
-    assert_equal 'blog_posts', @model_name.plural
+    assert_equal "blog_posts", @model_name.plural
   end
 
   def test_element
-    assert_equal 'post', @model_name.element
+    assert_equal "post", @model_name.element
   end
 
   def test_collection
-    assert_equal 'blog/posts', @model_name.collection
+    assert_equal "blog/posts", @model_name.collection
   end
 
   def test_human
-    assert_equal 'Post', @model_name.human
+    assert_equal "Post", @model_name.human
   end
 
   def test_route_key
-    assert_equal 'posts', @model_name.route_key
+    assert_equal "posts", @model_name.route_key
   end
 
   def test_param_key
-    assert_equal 'post', @model_name.param_key
+    assert_equal "post", @model_name.param_key
   end
 
   def test_i18n_key
@@ -86,31 +88,31 @@ class NamingWithNamespacedModelInSharedNamespaceTest < ActiveModel::TestCase
   end
 
   def test_singular
-    assert_equal 'blog_post', @model_name.singular
+    assert_equal "blog_post", @model_name.singular
   end
 
   def test_plural
-    assert_equal 'blog_posts', @model_name.plural
+    assert_equal "blog_posts", @model_name.plural
   end
 
   def test_element
-    assert_equal 'post', @model_name.element
+    assert_equal "post", @model_name.element
   end
 
   def test_collection
-    assert_equal 'blog/posts', @model_name.collection
+    assert_equal "blog/posts", @model_name.collection
   end
 
   def test_human
-    assert_equal 'Post', @model_name.human
+    assert_equal "Post", @model_name.human
   end
 
   def test_route_key
-    assert_equal 'blog_posts', @model_name.route_key
+    assert_equal "blog_posts", @model_name.route_key
   end
 
   def test_param_key
-    assert_equal 'blog_post', @model_name.param_key
+    assert_equal "blog_post", @model_name.param_key
   end
 
   def test_i18n_key
@@ -120,35 +122,35 @@ end
 
 class NamingWithSuppliedModelNameTest < ActiveModel::TestCase
   def setup
-    @model_name = ActiveModel::Name.new(Blog::Post, nil, 'Article')
+    @model_name = ActiveModel::Name.new(Blog::Post, nil, "Article")
   end
 
   def test_singular
-    assert_equal 'article', @model_name.singular
+    assert_equal "article", @model_name.singular
   end
 
   def test_plural
-    assert_equal 'articles', @model_name.plural
+    assert_equal "articles", @model_name.plural
   end
 
   def test_element
-    assert_equal 'article', @model_name.element
+    assert_equal "article", @model_name.element
   end
 
   def test_collection
-    assert_equal 'articles', @model_name.collection
+    assert_equal "articles", @model_name.collection
   end
 
   def test_human
-    assert_equal 'Article', @model_name.human
+    assert_equal "Article", @model_name.human
   end
 
   def test_route_key
-    assert_equal 'articles', @model_name.route_key
+    assert_equal "articles", @model_name.route_key
   end
 
   def test_param_key
-    assert_equal 'article', @model_name.param_key
+    assert_equal "article", @model_name.param_key
   end
 
   def test_i18n_key
@@ -162,31 +164,31 @@ class NamingUsingRelativeModelNameTest < ActiveModel::TestCase
   end
 
   def test_singular
-    assert_equal 'blog_post', @model_name.singular
+    assert_equal "blog_post", @model_name.singular
   end
 
   def test_plural
-    assert_equal 'blog_posts', @model_name.plural
+    assert_equal "blog_posts", @model_name.plural
   end
 
   def test_element
-    assert_equal 'post', @model_name.element
+    assert_equal "post", @model_name.element
   end
 
   def test_collection
-    assert_equal 'blog/posts', @model_name.collection
+    assert_equal "blog/posts", @model_name.collection
   end
 
   def test_human
-    assert_equal 'Post', @model_name.human
+    assert_equal "Post", @model_name.human
   end
 
   def test_route_key
-    assert_equal 'posts', @model_name.route_key
+    assert_equal "posts", @model_name.route_key
   end
 
   def test_param_key
-    assert_equal 'post', @model_name.param_key
+    assert_equal "post", @model_name.param_key
   end
 
   def test_i18n_key
@@ -198,16 +200,16 @@ class NamingHelpersTest < ActiveModel::TestCase
   def setup
     @klass  = Contact
     @record = @klass.new
-    @singular = 'contact'
-    @plural = 'contacts'
+    @singular = "contact"
+    @plural = "contacts"
     @uncountable = Sheep
-    @singular_route_key = 'contact'
-    @route_key = 'contacts'
-    @param_key = 'contact'
+    @singular_route_key = "contact"
+    @route_key = "contacts"
+    @param_key = "contact"
   end
 
   def test_to_model_called_on_record
-    assert_equal 'post_named_track_backs', plural(Post::TrackBack.new)
+    assert_equal "post_named_track_backs", plural(Post::TrackBack.new)
   end
 
   def test_singular
diff --git a/activemodel/test/cases/railtie_test.rb b/activemodel/test/cases/railtie_test.rb
index 96b3b07e50..ff5022e960 100644
--- a/activemodel/test/cases/railtie_test.rb
+++ b/activemodel/test/cases/railtie_test.rb
@@ -1,11 +1,13 @@
-require 'cases/helper'
-require 'active_support/testing/isolation'
+# frozen_string_literal: true
+
+require "cases/helper"
+require "active_support/testing/isolation"
 
 class RailtieTest < ActiveModel::TestCase
   include ActiveSupport::Testing::Isolation
 
   def setup
-    require 'active_model/railtie'
+    require "active_model/railtie"
 
     # Set a fake logger to avoid creating the log directory automatically
     fake_logger = Logger.new(nil)
@@ -16,15 +18,15 @@ class RailtieTest < ActiveModel::TestCase
     end
   end
 
-  test 'secure password min_cost is false in the development environment' do
-    Rails.env = 'development'
+  test "secure password min_cost is false in the development environment" do
+    Rails.env = "development"
     @app.initialize!
 
     assert_equal false, ActiveModel::SecurePassword.min_cost
   end
 
-  test 'secure password min_cost is true in the test environment' do
-    Rails.env = 'test'
+  test "secure password min_cost is true in the test environment" do
+    Rails.env = "test"
     @app.initialize!
 
     assert_equal true, ActiveModel::SecurePassword.min_cost
diff --git a/activemodel/test/cases/secure_password_test.rb b/activemodel/test/cases/secure_password_test.rb
index 6d56c8344a..d19e81a119 100644
--- a/activemodel/test/cases/secure_password_test.rb
+++ b/activemodel/test/cases/secure_password_test.rb
@@ -1,6 +1,8 @@
-require 'cases/helper'
-require 'models/user'
-require 'models/visitor'
+# frozen_string_literal: true
+
+require "cases/helper"
+require "models/user"
+require "models/visitor"
 
 class SecurePasswordTest < ActiveModel::TestCase
   setup do
@@ -13,7 +15,7 @@ class SecurePasswordTest < ActiveModel::TestCase
 
     # Simulate loading an existing user from the DB
     @existing_user = User.new
-    @existing_user.password_digest = BCrypt::Password.create('password', cost: BCrypt::Engine::MIN_COST)
+    @existing_user.password_digest = BCrypt::Password.create("password", cost: BCrypt::Engine::MIN_COST)
   end
 
   teardown do
@@ -29,157 +31,157 @@ class SecurePasswordTest < ActiveModel::TestCase
   end
 
   test "create a new user with validations and valid password/confirmation" do
-    @user.password = 'password'
-    @user.password_confirmation = 'password'
+    @user.password = "password"
+    @user.password_confirmation = "password"
 
-    assert @user.valid?(:create), 'user should be valid'
+    assert @user.valid?(:create), "user should be valid"
 
-    @user.password = 'a' * 72
-    @user.password_confirmation = 'a' * 72
+    @user.password = "a" * 72
+    @user.password_confirmation = "a" * 72
 
-    assert @user.valid?(:create), 'user should be valid'
+    assert @user.valid?(:create), "user should be valid"
   end
 
   test "create a new user with validation and a spaces only password" do
-    @user.password = ' ' * 72
-    assert @user.valid?(:create), 'user should be valid'
+    @user.password = " " * 72
+    assert @user.valid?(:create), "user should be valid"
   end
 
   test "create a new user with validation and a blank password" do
-    @user.password = ''
-    assert !@user.valid?(:create), 'user should be invalid'
+    @user.password = ""
+    assert !@user.valid?(:create), "user should be invalid"
     assert_equal 1, @user.errors.count
     assert_equal ["can't be blank"], @user.errors[:password]
   end
 
   test "create a new user with validation and a nil password" do
     @user.password = nil
-    assert !@user.valid?(:create), 'user should be invalid'
+    assert !@user.valid?(:create), "user should be invalid"
     assert_equal 1, @user.errors.count
     assert_equal ["can't be blank"], @user.errors[:password]
   end
 
-  test 'create a new user with validation and password length greater than 72' do
-    @user.password = 'a' * 73
-    @user.password_confirmation = 'a' * 73
-    assert !@user.valid?(:create), 'user should be invalid'
+  test "create a new user with validation and password length greater than 72" do
+    @user.password = "a" * 73
+    @user.password_confirmation = "a" * 73
+    assert !@user.valid?(:create), "user should be invalid"
     assert_equal 1, @user.errors.count
     assert_equal ["is too long (maximum is 72 characters)"], @user.errors[:password]
   end
 
   test "create a new user with validation and a blank password confirmation" do
-    @user.password = 'password'
-    @user.password_confirmation = ''
-    assert !@user.valid?(:create), 'user should be invalid'
+    @user.password = "password"
+    @user.password_confirmation = ""
+    assert !@user.valid?(:create), "user should be invalid"
     assert_equal 1, @user.errors.count
     assert_equal ["doesn't match Password"], @user.errors[:password_confirmation]
   end
 
   test "create a new user with validation and a nil password confirmation" do
-    @user.password = 'password'
+    @user.password = "password"
     @user.password_confirmation = nil
-    assert @user.valid?(:create), 'user should be valid'
+    assert @user.valid?(:create), "user should be valid"
   end
 
   test "create a new user with validation and an incorrect password confirmation" do
-    @user.password = 'password'
-    @user.password_confirmation = 'something else'
-    assert !@user.valid?(:create), 'user should be invalid'
+    @user.password = "password"
+    @user.password_confirmation = "something else"
+    assert !@user.valid?(:create), "user should be invalid"
     assert_equal 1, @user.errors.count
     assert_equal ["doesn't match Password"], @user.errors[:password_confirmation]
   end
 
   test "update an existing user with validation and no change in password" do
-    assert @existing_user.valid?(:update), 'user should be valid'
+    assert @existing_user.valid?(:update), "user should be valid"
   end
 
   test "update an existing user with validations and valid password/confirmation" do
-    @existing_user.password = 'password'
-    @existing_user.password_confirmation = 'password'
+    @existing_user.password = "password"
+    @existing_user.password_confirmation = "password"
 
-    assert @existing_user.valid?(:update), 'user should be valid'
+    assert @existing_user.valid?(:update), "user should be valid"
 
-    @existing_user.password = 'a' * 72
-    @existing_user.password_confirmation = 'a' * 72
+    @existing_user.password = "a" * 72
+    @existing_user.password_confirmation = "a" * 72
 
-    assert @existing_user.valid?(:update), 'user should be valid'
+    assert @existing_user.valid?(:update), "user should be valid"
   end
 
   test "updating an existing user with validation and a blank password" do
-    @existing_user.password = ''
-    assert @existing_user.valid?(:update), 'user should be valid'
+    @existing_user.password = ""
+    assert @existing_user.valid?(:update), "user should be valid"
   end
 
   test "updating an existing user with validation and a spaces only password" do
-    @user.password = ' ' * 72
-    assert @user.valid?(:update), 'user should be valid'
+    @user.password = " " * 72
+    assert @user.valid?(:update), "user should be valid"
   end
 
   test "updating an existing user with validation and a blank password and password_confirmation" do
-    @existing_user.password = ''
-    @existing_user.password_confirmation = ''
-    assert @existing_user.valid?(:update), 'user should be valid'
+    @existing_user.password = ""
+    @existing_user.password_confirmation = ""
+    assert @existing_user.valid?(:update), "user should be valid"
   end
 
   test "updating an existing user with validation and a nil password" do
     @existing_user.password = nil
-    assert !@existing_user.valid?(:update), 'user should be invalid'
+    assert !@existing_user.valid?(:update), "user should be invalid"
     assert_equal 1, @existing_user.errors.count
     assert_equal ["can't be blank"], @existing_user.errors[:password]
   end
 
-  test 'updating an existing user with validation and password length greater than 72' do
-    @existing_user.password = 'a' * 73
-    @existing_user.password_confirmation = 'a' * 73
-    assert !@existing_user.valid?(:update), 'user should be invalid'
+  test "updating an existing user with validation and password length greater than 72" do
+    @existing_user.password = "a" * 73
+    @existing_user.password_confirmation = "a" * 73
+    assert !@existing_user.valid?(:update), "user should be invalid"
     assert_equal 1, @existing_user.errors.count
     assert_equal ["is too long (maximum is 72 characters)"], @existing_user.errors[:password]
   end
 
   test "updating an existing user with validation and a blank password confirmation" do
-    @existing_user.password = 'password'
-    @existing_user.password_confirmation = ''
-    assert !@existing_user.valid?(:update), 'user should be invalid'
+    @existing_user.password = "password"
+    @existing_user.password_confirmation = ""
+    assert !@existing_user.valid?(:update), "user should be invalid"
     assert_equal 1, @existing_user.errors.count
     assert_equal ["doesn't match Password"], @existing_user.errors[:password_confirmation]
   end
 
   test "updating an existing user with validation and a nil password confirmation" do
-    @existing_user.password = 'password'
+    @existing_user.password = "password"
     @existing_user.password_confirmation = nil
-    assert @existing_user.valid?(:update), 'user should be valid'
+    assert @existing_user.valid?(:update), "user should be valid"
   end
 
   test "updating an existing user with validation and an incorrect password confirmation" do
-    @existing_user.password = 'password'
-    @existing_user.password_confirmation = 'something else'
-    assert !@existing_user.valid?(:update), 'user should be invalid'
+    @existing_user.password = "password"
+    @existing_user.password_confirmation = "something else"
+    assert !@existing_user.valid?(:update), "user should be invalid"
     assert_equal 1, @existing_user.errors.count
     assert_equal ["doesn't match Password"], @existing_user.errors[:password_confirmation]
   end
 
   test "updating an existing user with validation and a blank password digest" do
-    @existing_user.password_digest = ''
-    assert !@existing_user.valid?(:update), 'user should be invalid'
+    @existing_user.password_digest = ""
+    assert !@existing_user.valid?(:update), "user should be invalid"
     assert_equal 1, @existing_user.errors.count
     assert_equal ["can't be blank"], @existing_user.errors[:password]
   end
 
   test "updating an existing user with validation and a nil password digest" do
     @existing_user.password_digest = nil
-    assert !@existing_user.valid?(:update), 'user should be invalid'
+    assert !@existing_user.valid?(:update), "user should be invalid"
     assert_equal 1, @existing_user.errors.count
     assert_equal ["can't be blank"], @existing_user.errors[:password]
   end
 
   test "setting a blank password should not change an existing password" do
-    @existing_user.password = ''
-    assert @existing_user.password_digest == 'password'
+    @existing_user.password = ""
+    assert @existing_user.password_digest == "password"
   end
 
   test "setting a nil password should clear an existing password" do
     @existing_user.password = nil
-    assert_equal nil, @existing_user.password_digest
+    assert_nil @existing_user.password_digest
   end
 
   test "authenticate" do
diff --git a/activemodel/test/cases/serialization_test.rb b/activemodel/test/cases/serialization_test.rb
index 8d3165cd78..9002982e7f 100644
--- a/activemodel/test/cases/serialization_test.rb
+++ b/activemodel/test/cases/serialization_test.rb
@@ -1,5 +1,7 @@
+# frozen_string_literal: true
+
 require "cases/helper"
-require 'active_support/core_ext/object/instance_variables'
+require "active_support/core_ext/object/instance_variables"
 
 class SerializationTest < ActiveModel::TestCase
   class User
@@ -18,14 +20,14 @@ class SerializationTest < ActiveModel::TestCase
 
     def method_missing(method_name, *args)
       if method_name == :bar
-        'i_am_bar'
+        "i_am_bar"
       else
         super
       end
     end
 
     def foo
-      'i_am_foo'
+      "i_am_foo"
     end
   end
 
@@ -40,43 +42,43 @@ class SerializationTest < ActiveModel::TestCase
   end
 
   setup do
-    @user = User.new('David', 'david@example.com', 'male')
+    @user = User.new("David", "david@example.com", "male")
     @user.address = Address.new
     @user.address.street = "123 Lane"
     @user.address.city = "Springfield"
     @user.address.state = "CA"
     @user.address.zip = 11111
-    @user.friends = [User.new('Joe', 'joe@example.com', 'male'),
-                     User.new('Sue', 'sue@example.com', 'female')]
+    @user.friends = [User.new("Joe", "joe@example.com", "male"),
+                     User.new("Sue", "sue@example.com", "female")]
   end
 
   def test_method_serializable_hash_should_work
-    expected = {"name"=>"David", "gender"=>"male", "email"=>"david@example.com"}
+    expected = { "name" => "David", "gender" => "male", "email" => "david@example.com" }
     assert_equal expected, @user.serializable_hash
   end
 
   def test_method_serializable_hash_should_work_with_only_option
-    expected = {"name"=>"David"}
+    expected = { "name" => "David" }
     assert_equal expected, @user.serializable_hash(only: [:name])
   end
 
   def test_method_serializable_hash_should_work_with_except_option
-    expected = {"gender"=>"male", "email"=>"david@example.com"}
+    expected = { "gender" => "male", "email" => "david@example.com" }
     assert_equal expected, @user.serializable_hash(except: [:name])
   end
 
   def test_method_serializable_hash_should_work_with_methods_option
-    expected = {"name"=>"David", "gender"=>"male", "foo"=>"i_am_foo", "bar"=>"i_am_bar", "email"=>"david@example.com"}
+    expected = { "name" => "David", "gender" => "male", "foo" => "i_am_foo", "bar" => "i_am_bar", "email" => "david@example.com" }
     assert_equal expected, @user.serializable_hash(methods: [:foo, :bar])
   end
 
   def test_method_serializable_hash_should_work_with_only_and_methods
-    expected = {"foo"=>"i_am_foo", "bar"=>"i_am_bar"}
+    expected = { "foo" => "i_am_foo", "bar" => "i_am_bar" }
     assert_equal expected, @user.serializable_hash(only: [], methods: [:foo, :bar])
   end
 
   def test_method_serializable_hash_should_work_with_except_and_methods
-    expected = {"gender"=>"male", "foo"=>"i_am_foo", "bar"=>"i_am_bar"}
+    expected = { "gender" => "male", "foo" => "i_am_foo", "bar" => "i_am_bar" }
     assert_equal expected, @user.serializable_hash(except: [:name, :email], methods: [:foo, :bar])
   end
 
@@ -94,21 +96,21 @@ class SerializationTest < ActiveModel::TestCase
   end
 
   def test_include_option_with_singular_association
-    expected = {"name"=>"David", "gender"=>"male", "email"=>"david@example.com",
-                "address"=>{"street"=>"123 Lane", "city"=>"Springfield", "state"=>"CA", "zip"=>11111}}
+    expected = { "name" => "David", "gender" => "male", "email" => "david@example.com",
+                "address" => { "street" => "123 Lane", "city" => "Springfield", "state" => "CA", "zip" => 11111 } }
     assert_equal expected, @user.serializable_hash(include: :address)
   end
 
   def test_include_option_with_plural_association
-    expected = {"email"=>"david@example.com", "gender"=>"male", "name"=>"David",
-                "friends"=>[{"name"=>'Joe', "email"=>'joe@example.com', "gender"=>'male'},
-                           {"name"=>'Sue', "email"=>'sue@example.com', "gender"=>'female'}]}
+    expected = { "email" => "david@example.com", "gender" => "male", "name" => "David",
+                "friends" => [{ "name" => "Joe", "email" => "joe@example.com", "gender" => "male" },
+                           { "name" => "Sue", "email" => "sue@example.com", "gender" => "female" }] }
     assert_equal expected, @user.serializable_hash(include: :friends)
   end
 
   def test_include_option_with_empty_association
     @user.friends = []
-    expected = {"email"=>"david@example.com", "gender"=>"male", "name"=>"David", "friends"=>[]}
+    expected = { "email" => "david@example.com", "gender" => "male", "name" => "David", "friends" => [] }
     assert_equal expected, @user.serializable_hash(include: :friends)
   end
 
@@ -124,52 +126,52 @@ class SerializationTest < ActiveModel::TestCase
 
   def test_include_option_with_ary
     @user.friends = FriendList.new(@user.friends)
-    expected = {"email"=>"david@example.com", "gender"=>"male", "name"=>"David",
-                "friends"=>[{"name"=>'Joe', "email"=>'joe@example.com', "gender"=>'male'},
-                           {"name"=>'Sue', "email"=>'sue@example.com', "gender"=>'female'}]}
+    expected = { "email" => "david@example.com", "gender" => "male", "name" => "David",
+                "friends" => [{ "name" => "Joe", "email" => "joe@example.com", "gender" => "male" },
+                           { "name" => "Sue", "email" => "sue@example.com", "gender" => "female" }] }
     assert_equal expected, @user.serializable_hash(include: :friends)
   end
 
   def test_multiple_includes
-    expected = {"email"=>"david@example.com", "gender"=>"male", "name"=>"David",
-                "address"=>{"street"=>"123 Lane", "city"=>"Springfield", "state"=>"CA", "zip"=>11111},
-                "friends"=>[{"name"=>'Joe', "email"=>'joe@example.com', "gender"=>'male'},
-                           {"name"=>'Sue', "email"=>'sue@example.com', "gender"=>'female'}]}
+    expected = { "email" => "david@example.com", "gender" => "male", "name" => "David",
+                "address" => { "street" => "123 Lane", "city" => "Springfield", "state" => "CA", "zip" => 11111 },
+                "friends" => [{ "name" => "Joe", "email" => "joe@example.com", "gender" => "male" },
+                           { "name" => "Sue", "email" => "sue@example.com", "gender" => "female" }] }
     assert_equal expected, @user.serializable_hash(include: [:address, :friends])
   end
 
   def test_include_with_options
-    expected = {"email"=>"david@example.com", "gender"=>"male", "name"=>"David",
-                "address"=>{"street"=>"123 Lane"}}
+    expected = { "email" => "david@example.com", "gender" => "male", "name" => "David",
+                "address" => { "street" => "123 Lane" } }
     assert_equal expected, @user.serializable_hash(include: { address: { only: "street" } })
   end
 
   def test_nested_include
     @user.friends.first.friends = [@user]
-    expected = {"email"=>"david@example.com", "gender"=>"male", "name"=>"David",
-                "friends"=>[{"name"=>'Joe', "email"=>'joe@example.com', "gender"=>'male',
-                            "friends"=> [{"email"=>"david@example.com", "gender"=>"male", "name"=>"David"}]},
-                            {"name"=>'Sue', "email"=>'sue@example.com', "gender"=>'female', "friends"=> []}]}
+    expected = { "email" => "david@example.com", "gender" => "male", "name" => "David",
+                "friends" => [{ "name" => "Joe", "email" => "joe@example.com", "gender" => "male",
+                            "friends" => [{ "email" => "david@example.com", "gender" => "male", "name" => "David" }] },
+                            { "name" => "Sue", "email" => "sue@example.com", "gender" => "female", "friends" => [] }] }
     assert_equal expected, @user.serializable_hash(include: { friends: { include: :friends } })
   end
 
   def test_only_include
-    expected = {"name"=>"David", "friends" => [{"name" => "Joe"}, {"name" => "Sue"}]}
+    expected = { "name" => "David", "friends" => [{ "name" => "Joe" }, { "name" => "Sue" }] }
     assert_equal expected, @user.serializable_hash(only: :name, include: { friends: { only: :name } })
   end
 
   def test_except_include
-    expected = {"name"=>"David", "email"=>"david@example.com",
-                "friends"=> [{"name" => 'Joe', "email" => 'joe@example.com'},
-                             {"name" => "Sue", "email" => 'sue@example.com'}]}
+    expected = { "name" => "David", "email" => "david@example.com",
+                "friends" => [{ "name" => "Joe", "email" => "joe@example.com" },
+                             { "name" => "Sue", "email" => "sue@example.com" }] }
     assert_equal expected, @user.serializable_hash(except: :gender, include: { friends: { except: :gender } })
   end
 
   def test_multiple_includes_with_options
-    expected = {"email"=>"david@example.com", "gender"=>"male", "name"=>"David",
-                "address"=>{"street"=>"123 Lane"},
-                "friends"=>[{"name"=>'Joe', "email"=>'joe@example.com', "gender"=>'male'},
-                           {"name"=>'Sue', "email"=>'sue@example.com', "gender"=>'female'}]}
-    assert_equal expected, @user.serializable_hash(include: [{ address: {only: "street" } }, :friends])
+    expected = { "email" => "david@example.com", "gender" => "male", "name" => "David",
+                "address" => { "street" => "123 Lane" },
+                "friends" => [{ "name" => "Joe", "email" => "joe@example.com", "gender" => "male" },
+                           { "name" => "Sue", "email" => "sue@example.com", "gender" => "female" }] }
+    assert_equal expected, @user.serializable_hash(include: [{ address: { only: "street" } }, :friends])
   end
 end
diff --git a/activemodel/test/cases/serializers/json_serialization_test.rb b/activemodel/test/cases/serializers/json_serialization_test.rb
index d765a47636..aae98c9fe4 100644
--- a/activemodel/test/cases/serializers/json_serialization_test.rb
+++ b/activemodel/test/cases/serializers/json_serialization_test.rb
@@ -1,15 +1,17 @@
-require 'cases/helper'
-require 'models/contact'
-require 'active_support/core_ext/object/instance_variables'
+# frozen_string_literal: true
+
+require "cases/helper"
+require "models/contact"
+require "active_support/core_ext/object/instance_variables"
 
 class JsonSerializationTest < ActiveModel::TestCase
   def setup
     @contact = Contact.new
-    @contact.name = 'Konata Izumi'
+    @contact.name = "Konata Izumi"
     @contact.age = 16
     @contact.created_at = Time.utc(2006, 8, 1)
     @contact.awesome = true
-    @contact.preferences = { 'shows' => 'anime' }
+    @contact.preferences = { "shows" => "anime" }
   end
 
   test "should not include root in json (class method)" do
@@ -18,7 +20,7 @@ class JsonSerializationTest < ActiveModel::TestCase
     assert_no_match %r{^\{"contact":\{}, json
     assert_match %r{"name":"Konata Izumi"}, json
     assert_match %r{"age":16}, json
-    assert json.include?(%("created_at":#{ActiveSupport::JSON.encode(Time.utc(2006, 8, 1))}))
+    assert_includes json, %("created_at":#{ActiveSupport::JSON.encode(Time.utc(2006, 8, 1))})
     assert_match %r{"awesome":true}, json
     assert_match %r{"preferences":\{"shows":"anime"\}}, json
   end
@@ -32,7 +34,7 @@ class JsonSerializationTest < ActiveModel::TestCase
       assert_match %r{^\{"contact":\{}, json
       assert_match %r{"name":"Konata Izumi"}, json
       assert_match %r{"age":16}, json
-      assert json.include?(%("created_at":#{ActiveSupport::JSON.encode(Time.utc(2006, 8, 1))}))
+      assert_includes json, %("created_at":#{ActiveSupport::JSON.encode(Time.utc(2006, 8, 1))})
       assert_match %r{"awesome":true}, json
       assert_match %r{"preferences":\{"shows":"anime"\}}, json
     ensure
@@ -53,12 +55,12 @@ class JsonSerializationTest < ActiveModel::TestCase
   end
 
   test "should include custom root in json" do
-    json = @contact.to_json(root: 'json_contact')
+    json = @contact.to_json(root: "json_contact")
 
     assert_match %r{^\{"json_contact":\{}, json
     assert_match %r{"name":"Konata Izumi"}, json
     assert_match %r{"age":16}, json
-    assert json.include?(%("created_at":#{ActiveSupport::JSON.encode(Time.utc(2006, 8, 1))}))
+    assert_includes json, %("created_at":#{ActiveSupport::JSON.encode(Time.utc(2006, 8, 1))})
     assert_match %r{"awesome":true}, json
     assert_match %r{"preferences":\{"shows":"anime"\}}, json
   end
@@ -68,7 +70,7 @@ class JsonSerializationTest < ActiveModel::TestCase
 
     assert_match %r{"name":"Konata Izumi"}, json
     assert_match %r{"age":16}, json
-    assert json.include?(%("created_at":#{ActiveSupport::JSON.encode(Time.utc(2006, 8, 1))}))
+    assert_includes json, %("created_at":#{ActiveSupport::JSON.encode(Time.utc(2006, 8, 1))})
     assert_match %r{"awesome":true}, json
     assert_match %r{"preferences":\{"shows":"anime"\}}, json
   end
@@ -79,7 +81,7 @@ class JsonSerializationTest < ActiveModel::TestCase
     assert_match %r{"name":"Konata Izumi"}, json
     assert_match %r{"age":16}, json
     assert_no_match %r{"awesome":true}, json
-    assert !json.include?(%("created_at":#{ActiveSupport::JSON.encode(Time.utc(2006, 8, 1))}))
+    assert_not_includes json, %("created_at":#{ActiveSupport::JSON.encode(Time.utc(2006, 8, 1))})
     assert_no_match %r{"preferences":\{"shows":"anime"\}}, json
   end
 
@@ -89,7 +91,7 @@ class JsonSerializationTest < ActiveModel::TestCase
     assert_no_match %r{"name":"Konata Izumi"}, json
     assert_no_match %r{"age":16}, json
     assert_match %r{"awesome":true}, json
-    assert json.include?(%("created_at":#{ActiveSupport::JSON.encode(Time.utc(2006, 8, 1))}))
+    assert_includes json, %("created_at":#{ActiveSupport::JSON.encode(Time.utc(2006, 8, 1))})
     assert_match %r{"preferences":\{"shows":"anime"\}}, json
   end
 
@@ -134,9 +136,9 @@ class JsonSerializationTest < ActiveModel::TestCase
       json = @contact.as_json
 
       assert_kind_of Hash, json
-      assert_kind_of Hash, json['contact']
+      assert_kind_of Hash, json["contact"]
       %w(name age created_at awesome preferences).each do |field|
-        assert_equal @contact.send(field), json['contact'][field]
+        assert_equal @contact.send(field), json["contact"][field]
       end
     ensure
       Contact.include_root_in_json = original_include_root_in_json
diff --git a/activemodel/test/cases/translation_test.rb b/activemodel/test/cases/translation_test.rb
index 2c89388f14..cd75afec9e 100644
--- a/activemodel/test/cases/translation_test.rb
+++ b/activemodel/test/cases/translation_test.rb
@@ -1,8 +1,9 @@
-require 'cases/helper'
-require 'models/person'
+# frozen_string_literal: true
 
-class ActiveModelI18nTests < ActiveModel::TestCase
+require "cases/helper"
+require "models/person"
 
+class ActiveModelI18nTests < ActiveModel::TestCase
   def setup
     I18n.backend = I18n::Backend::Simple.new
   end
@@ -12,102 +13,101 @@ class ActiveModelI18nTests < ActiveModel::TestCase
   end
 
   def test_translated_model_attributes
-    I18n.backend.store_translations 'en', activemodel: { attributes: { person: { name: 'person name attribute' } } }
-    assert_equal 'person name attribute', Person.human_attribute_name('name')
+    I18n.backend.store_translations "en", activemodel: { attributes: { person: { name: "person name attribute" } } }
+    assert_equal "person name attribute", Person.human_attribute_name("name")
   end
 
   def test_translated_model_attributes_with_default
-    I18n.backend.store_translations 'en', attributes: { name: 'name default attribute' }
-    assert_equal 'name default attribute', Person.human_attribute_name('name')
+    I18n.backend.store_translations "en", attributes: { name: "name default attribute" }
+    assert_equal "name default attribute", Person.human_attribute_name("name")
   end
 
   def test_translated_model_attributes_using_default_option
-    assert_equal 'name default attribute', Person.human_attribute_name('name', default: "name default attribute")
+    assert_equal "name default attribute", Person.human_attribute_name("name", default: "name default attribute")
   end
 
   def test_translated_model_attributes_using_default_option_as_symbol
-    I18n.backend.store_translations 'en', default_name: 'name default attribute'
-    assert_equal 'name default attribute', Person.human_attribute_name('name', default: :default_name)
+    I18n.backend.store_translations "en", default_name: "name default attribute"
+    assert_equal "name default attribute", Person.human_attribute_name("name", default: :default_name)
   end
 
   def test_translated_model_attributes_falling_back_to_default
-    assert_equal 'Name', Person.human_attribute_name('name')
+    assert_equal "Name", Person.human_attribute_name("name")
   end
 
   def test_translated_model_attributes_using_default_option_as_symbol_and_falling_back_to_default
-    assert_equal 'Name', Person.human_attribute_name('name', default: :default_name)
+    assert_equal "Name", Person.human_attribute_name("name", default: :default_name)
   end
 
   def test_translated_model_attributes_with_symbols
-    I18n.backend.store_translations 'en', activemodel: { attributes: { person: { name: 'person name attribute'} } }
-    assert_equal 'person name attribute', Person.human_attribute_name(:name)
+    I18n.backend.store_translations "en", activemodel: { attributes: { person: { name: "person name attribute" } } }
+    assert_equal "person name attribute", Person.human_attribute_name(:name)
   end
 
   def test_translated_model_attributes_with_ancestor
-    I18n.backend.store_translations 'en', activemodel: { attributes: { child: { name: 'child name attribute'} } }
-    assert_equal 'child name attribute', Child.human_attribute_name('name')
+    I18n.backend.store_translations "en", activemodel: { attributes: { child: { name: "child name attribute" } } }
+    assert_equal "child name attribute", Child.human_attribute_name("name")
   end
 
   def test_translated_model_attributes_with_ancestors_fallback
-    I18n.backend.store_translations 'en', activemodel: { attributes: { person: { name: 'person name attribute'} } }
-    assert_equal 'person name attribute', Child.human_attribute_name('name')
+    I18n.backend.store_translations "en", activemodel: { attributes: { person: { name: "person name attribute" } } }
+    assert_equal "person name attribute", Child.human_attribute_name("name")
   end
 
   def test_translated_model_attributes_with_attribute_matching_namespaced_model_name
-    I18n.backend.store_translations 'en', activemodel: { attributes: {
-      person: { gender: 'person gender'},
-      :"person/gender" => { attribute: 'person gender attribute' }
+    I18n.backend.store_translations "en", activemodel: { attributes: {
+      person: { gender: "person gender" },
+      "person/gender": { attribute: "person gender attribute" }
     } }
 
-    assert_equal 'person gender', Person.human_attribute_name('gender')
-    assert_equal 'person gender attribute', Person::Gender.human_attribute_name('attribute')
+    assert_equal "person gender", Person.human_attribute_name("gender")
+    assert_equal "person gender attribute", Person::Gender.human_attribute_name("attribute")
   end
 
   def test_translated_deeply_nested_model_attributes
-    I18n.backend.store_translations 'en', activemodel: { attributes: { :"person/contacts/addresses" => { street: 'Deeply Nested Address Street' } } }
-    assert_equal 'Deeply Nested Address Street', Person.human_attribute_name('contacts.addresses.street')
+    I18n.backend.store_translations "en", activemodel: { attributes: { "person/contacts/addresses": { street: "Deeply Nested Address Street" } } }
+    assert_equal "Deeply Nested Address Street", Person.human_attribute_name("contacts.addresses.street")
   end
 
   def test_translated_nested_model_attributes
-    I18n.backend.store_translations 'en', activemodel: { attributes: { :"person/addresses" => { street: 'Person Address Street' } } }
-    assert_equal 'Person Address Street', Person.human_attribute_name('addresses.street')
+    I18n.backend.store_translations "en", activemodel: { attributes: { "person/addresses": { street: "Person Address Street" } } }
+    assert_equal "Person Address Street", Person.human_attribute_name("addresses.street")
   end
 
   def test_translated_nested_model_attributes_with_namespace_fallback
-    I18n.backend.store_translations 'en', activemodel: { attributes: { addresses: { street: 'Cool Address Street' } } }
-    assert_equal 'Cool Address Street', Person.human_attribute_name('addresses.street')
+    I18n.backend.store_translations "en", activemodel: { attributes: { addresses: { street: "Cool Address Street" } } }
+    assert_equal "Cool Address Street", Person.human_attribute_name("addresses.street")
   end
 
   def test_translated_model_names
-    I18n.backend.store_translations 'en', activemodel: { models: { person: 'person model' } }
-    assert_equal 'person model', Person.model_name.human
+    I18n.backend.store_translations "en", activemodel: { models: { person: "person model" } }
+    assert_equal "person model", Person.model_name.human
   end
 
   def test_translated_model_names_with_sti
-    I18n.backend.store_translations 'en', activemodel: { models: { child: 'child model' } }
-    assert_equal 'child model', Child.model_name.human
+    I18n.backend.store_translations "en", activemodel: { models: { child: "child model" } }
+    assert_equal "child model", Child.model_name.human
   end
 
   def test_translated_model_with_namespace
-    I18n.backend.store_translations 'en', activemodel: { models: { 'person/gender': 'gender model' } }
-    assert_equal 'gender model', Person::Gender.model_name.human
+    I18n.backend.store_translations "en", activemodel: { models: { 'person/gender': "gender model" } }
+    assert_equal "gender model", Person::Gender.model_name.human
   end
 
   def test_translated_model_names_with_ancestors_fallback
-    I18n.backend.store_translations 'en', activemodel: { models: { person: 'person model' } }
-    assert_equal 'person model', Child.model_name.human
+    I18n.backend.store_translations "en", activemodel: { models: { person: "person model" } }
+    assert_equal "person model", Child.model_name.human
   end
 
   def test_human_does_not_modify_options
-    options = { default: 'person model' }
+    options = { default: "person model" }
     Person.model_name.human(options)
-    assert_equal({ default: 'person model' }, options)
+    assert_equal({ default: "person model" }, options)
   end
 
   def test_human_attribute_name_does_not_modify_options
-    options = { default: 'Cool gender' }
-    Person.human_attribute_name('gender', options)
-    assert_equal({ default: 'Cool gender' }, options)
+    options = { default: "Cool gender" }
+    Person.human_attribute_name("gender", options)
+    assert_equal({ default: "Cool gender" }, options)
   end
 end
-
diff --git a/activemodel/test/cases/type/big_integer_test.rb b/activemodel/test/cases/type/big_integer_test.rb
new file mode 100644
index 0000000000..0fa0200df4
--- /dev/null
+++ b/activemodel/test/cases/type/big_integer_test.rb
@@ -0,0 +1,25 @@
+# frozen_string_literal: true
+
+require "cases/helper"
+
+module ActiveModel
+  module Type
+    class BigIntegerTest < ActiveModel::TestCase
+      def test_type_cast_big_integer
+        type = Type::BigInteger.new
+        assert_equal 1, type.cast(1)
+        assert_equal 1, type.cast("1")
+      end
+
+      def test_small_values
+        type = Type::BigInteger.new
+        assert_equal(-9999999999999999999999999999999, type.serialize(-9999999999999999999999999999999))
+      end
+
+      def test_large_values
+        type = Type::BigInteger.new
+        assert_equal 9999999999999999999999999999999, type.serialize(9999999999999999999999999999999)
+      end
+    end
+  end
+end
diff --git a/activemodel/test/cases/type/binary_test.rb b/activemodel/test/cases/type/binary_test.rb
new file mode 100644
index 0000000000..3221a73e49
--- /dev/null
+++ b/activemodel/test/cases/type/binary_test.rb
@@ -0,0 +1,16 @@
+# frozen_string_literal: true
+
+require "cases/helper"
+
+module ActiveModel
+  module Type
+    class BinaryTest < ActiveModel::TestCase
+      def test_type_cast_binary
+        type = Type::Binary.new
+        assert_nil type.cast(nil)
+        assert_equal "1", type.cast("1")
+        assert_equal 1, type.cast(1)
+      end
+    end
+  end
+end
diff --git a/activemodel/test/cases/type/boolean_test.rb b/activemodel/test/cases/type/boolean_test.rb
new file mode 100644
index 0000000000..2d33579595
--- /dev/null
+++ b/activemodel/test/cases/type/boolean_test.rb
@@ -0,0 +1,40 @@
+# frozen_string_literal: true
+
+require "cases/helper"
+
+module ActiveModel
+  module Type
+    class BooleanTest < ActiveModel::TestCase
+      def test_type_cast_boolean
+        type = Type::Boolean.new
+        assert type.cast("").nil?
+        assert type.cast(nil).nil?
+
+        assert type.cast(true)
+        assert type.cast(1)
+        assert type.cast("1")
+        assert type.cast("t")
+        assert type.cast("T")
+        assert type.cast("true")
+        assert type.cast("TRUE")
+        assert type.cast("on")
+        assert type.cast("ON")
+        assert type.cast(" ")
+        assert type.cast("\u3000\r\n")
+        assert type.cast("\u0000")
+        assert type.cast("SOMETHING RANDOM")
+
+        # explicitly check for false vs nil
+        assert_equal false, type.cast(false)
+        assert_equal false, type.cast(0)
+        assert_equal false, type.cast("0")
+        assert_equal false, type.cast("f")
+        assert_equal false, type.cast("F")
+        assert_equal false, type.cast("false")
+        assert_equal false, type.cast("FALSE")
+        assert_equal false, type.cast("off")
+        assert_equal false, type.cast("OFF")
+      end
+    end
+  end
+end
diff --git a/activemodel/test/cases/type/date_test.rb b/activemodel/test/cases/type/date_test.rb
new file mode 100644
index 0000000000..e8cf178612
--- /dev/null
+++ b/activemodel/test/cases/type/date_test.rb
@@ -0,0 +1,20 @@
+# frozen_string_literal: true
+
+require "cases/helper"
+
+module ActiveModel
+  module Type
+    class DateTest < ActiveModel::TestCase
+      def test_type_cast_date
+        type = Type::Date.new
+        assert_nil type.cast(nil)
+        assert_nil type.cast("")
+        assert_nil type.cast(" ")
+        assert_nil type.cast("ABC")
+
+        date_string = ::Time.now.utc.strftime("%F")
+        assert_equal date_string, type.cast(date_string).strftime("%F")
+      end
+    end
+  end
+end
diff --git a/activemodel/test/cases/type/date_time_test.rb b/activemodel/test/cases/type/date_time_test.rb
new file mode 100644
index 0000000000..60f62becc2
--- /dev/null
+++ b/activemodel/test/cases/type/date_time_test.rb
@@ -0,0 +1,39 @@
+# frozen_string_literal: true
+
+require "cases/helper"
+
+module ActiveModel
+  module Type
+    class DateTimeTest < ActiveModel::TestCase
+      def test_type_cast_datetime_and_timestamp
+        type = Type::DateTime.new
+        assert_nil type.cast(nil)
+        assert_nil type.cast("")
+        assert_nil type.cast("  ")
+        assert_nil type.cast("ABC")
+
+        datetime_string = ::Time.now.utc.strftime("%FT%T")
+        assert_equal datetime_string, type.cast(datetime_string).strftime("%FT%T")
+      end
+
+      def test_string_to_time_with_timezone
+        ["UTC", "US/Eastern"].each do |zone|
+          with_timezone_config default: zone do
+            type = Type::DateTime.new
+            assert_equal ::Time.utc(2013, 9, 4, 0, 0, 0), type.cast("Wed, 04 Sep 2013 03:00:00 EAT")
+          end
+        end
+      end
+
+      private
+
+        def with_timezone_config(default:)
+          old_zone_default = ::Time.zone_default
+          ::Time.zone_default = ::Time.find_zone(default)
+          yield
+        ensure
+          ::Time.zone_default = old_zone_default
+        end
+    end
+  end
+end
diff --git a/activemodel/test/cases/type/decimal_test.rb b/activemodel/test/cases/type/decimal_test.rb
index 1950566c0e..c0cf6ce590 100644
--- a/activemodel/test/cases/type/decimal_test.rb
+++ b/activemodel/test/cases/type/decimal_test.rb
@@ -1,19 +1,28 @@
+# frozen_string_literal: true
+
 require "cases/helper"
-require "active_model/type"
 
 module ActiveModel
   module Type
     class DecimalTest < ActiveModel::TestCase
       def test_type_cast_decimal
         type = Decimal.new
-        assert_equal BigDecimal.new("0"), type.cast(BigDecimal.new("0"))
-        assert_equal BigDecimal.new("123"), type.cast(123.0)
-        assert_equal BigDecimal.new("1"), type.cast(:"1")
+        assert_equal BigDecimal("0"), type.cast(BigDecimal("0"))
+        assert_equal BigDecimal("123"), type.cast(123.0)
+        assert_equal BigDecimal("1"), type.cast(:"1")
+      end
+
+      def test_type_cast_decimal_from_invalid_string
+        type = Decimal.new
+        assert_nil type.cast("")
+        assert_equal BigDecimal("1"), type.cast("1ignore")
+        assert_equal BigDecimal("0"), type.cast("bad1")
+        assert_equal BigDecimal("0"), type.cast("bad")
       end
 
       def test_type_cast_decimal_from_float_with_large_precision
         type = Decimal.new(precision: ::Float::DIG + 2)
-        assert_equal BigDecimal.new("123.0"), type.cast(123.0)
+        assert_equal BigDecimal("123.0"), type.cast(123.0)
       end
 
       def test_type_cast_from_float_with_unspecified_precision
@@ -39,7 +48,7 @@ module ActiveModel
       def test_type_cast_decimal_from_object_responding_to_d
         value = Object.new
         def value.to_d
-          BigDecimal.new("1")
+          BigDecimal("1")
         end
         type = Decimal.new
         assert_equal BigDecimal("1"), type.cast(value)
@@ -48,9 +57,9 @@ module ActiveModel
       def test_changed?
         type = Decimal.new
 
-        assert type.changed?(5.0, 5.0, '5.0wibble')
-        assert_not type.changed?(5.0, 5.0, '5.0')
-        assert_not type.changed?(-5.0, -5.0, '-5.0')
+        assert type.changed?(5.0, 5.0, "5.0wibble")
+        assert_not type.changed?(5.0, 5.0, "5.0")
+        assert_not type.changed?(-5.0, -5.0, "-5.0")
       end
 
       def test_scale_is_applied_before_precision_to_prevent_rounding_errors
diff --git a/activemodel/test/cases/type/float_test.rb b/activemodel/test/cases/type/float_test.rb
new file mode 100644
index 0000000000..28318e06f8
--- /dev/null
+++ b/activemodel/test/cases/type/float_test.rb
@@ -0,0 +1,31 @@
+# frozen_string_literal: true
+
+require "cases/helper"
+
+module ActiveModel
+  module Type
+    class FloatTest < ActiveModel::TestCase
+      def test_type_cast_float
+        type = Type::Float.new
+        assert_equal 1.0, type.cast("1")
+      end
+
+      def test_type_cast_float_from_invalid_string
+        type = Type::Float.new
+        assert_nil type.cast("")
+        assert_equal 1.0, type.cast("1ignore")
+        assert_equal 0.0, type.cast("bad1")
+        assert_equal 0.0, type.cast("bad")
+      end
+
+      def test_changing_float
+        type = Type::Float.new
+
+        assert type.changed?(5.0, 5.0, "5wibble")
+        assert_not type.changed?(5.0, 5.0, "5")
+        assert_not type.changed?(5.0, 5.0, "5.0")
+        assert_not type.changed?(nil, nil, nil)
+      end
+    end
+  end
+end
diff --git a/activemodel/test/cases/type/immutable_string_test.rb b/activemodel/test/cases/type/immutable_string_test.rb
new file mode 100644
index 0000000000..751f753ddb
--- /dev/null
+++ b/activemodel/test/cases/type/immutable_string_test.rb
@@ -0,0 +1,22 @@
+# frozen_string_literal: true
+
+require "cases/helper"
+
+module ActiveModel
+  module Type
+    class ImmutableStringTest < ActiveModel::TestCase
+      test "cast strings are frozen" do
+        s = "foo"
+        type = Type::ImmutableString.new
+        assert_equal true, type.cast(s).frozen?
+      end
+
+      test "immutable strings are not duped coming out" do
+        s = "foo"
+        type = Type::ImmutableString.new
+        assert_same s, type.cast(s)
+        assert_same s, type.deserialize(s)
+      end
+    end
+  end
+end
diff --git a/activemodel/test/cases/type/integer_test.rb b/activemodel/test/cases/type/integer_test.rb
index 6603f25c9a..8c5d18c9b3 100644
--- a/activemodel/test/cases/type/integer_test.rb
+++ b/activemodel/test/cases/type/integer_test.rb
@@ -1,16 +1,19 @@
+# frozen_string_literal: true
+
 require "cases/helper"
-require "active_model/type"
+require "active_support/core_ext/numeric/time"
 
 module ActiveModel
   module Type
     class IntegerTest < ActiveModel::TestCase
       test "simple values" do
         type = Type::Integer.new
+        assert_nil type.cast("")
         assert_equal 1, type.cast(1)
-        assert_equal 1, type.cast('1')
-        assert_equal 1, type.cast('1ignore')
-        assert_equal 0, type.cast('bad1')
-        assert_equal 0, type.cast('bad')
+        assert_equal 1, type.cast("1")
+        assert_equal 1, type.cast("1ignore")
+        assert_equal 0, type.cast("bad1")
+        assert_equal 0, type.cast("bad")
         assert_equal 1, type.cast(1.7)
         assert_equal 0, type.cast(false)
         assert_equal 1, type.cast(true)
@@ -19,8 +22,8 @@ module ActiveModel
 
       test "random objects cast to nil" do
         type = Type::Integer.new
-        assert_nil type.cast([1,2])
-        assert_nil type.cast({1 => 2})
+        assert_nil type.cast([1, 2])
+        assert_nil type.cast(1 => 2)
         assert_nil type.cast(1..2)
       end
 
@@ -32,7 +35,7 @@ module ActiveModel
       test "casting nan and infinity" do
         type = Type::Integer.new
         assert_nil type.cast(::Float::NAN)
-        assert_nil type.cast(1.0/0.0)
+        assert_nil type.cast(1.0 / 0.0)
       end
 
       test "casting booleans for database" do
@@ -41,14 +44,20 @@ module ActiveModel
         assert_equal 0, type.serialize(false)
       end
 
+      test "casting duration" do
+        type = Type::Integer.new
+        assert_equal 1800, type.cast(30.minutes)
+        assert_equal 7200, type.cast(2.hours)
+      end
+
       test "changed?" do
         type = Type::Integer.new
 
-        assert type.changed?(5, 5, '5wibble')
-        assert_not type.changed?(5, 5, '5')
-        assert_not type.changed?(5, 5, '5.0')
-        assert_not type.changed?(-5, -5, '-5')
-        assert_not type.changed?(-5, -5, '-5.0')
+        assert type.changed?(5, 5, "5wibble")
+        assert_not type.changed?(5, 5, "5")
+        assert_not type.changed?(5, 5, "5.0")
+        assert_not type.changed?(-5, -5, "-5")
+        assert_not type.changed?(-5, -5, "-5.0")
         assert_not type.changed?(nil, nil, nil)
       end
 
diff --git a/activemodel/test/cases/type/registry_test.rb b/activemodel/test/cases/type/registry_test.rb
index 2a48998a62..0633ea2538 100644
--- a/activemodel/test/cases/type/registry_test.rb
+++ b/activemodel/test/cases/type/registry_test.rb
@@ -1,39 +1,42 @@
+# frozen_string_literal: true
+
 require "cases/helper"
-require "active_model/type"
 
 module ActiveModel
-  class RegistryTest < ActiveModel::TestCase
-    test "a class can be registered for a symbol" do
-      registry = Type::Registry.new
-      registry.register(:foo, ::String)
-      registry.register(:bar, ::Array)
-
-      assert_equal "", registry.lookup(:foo)
-      assert_equal [], registry.lookup(:bar)
-    end
+  module Type
+    class RegistryTest < ActiveModel::TestCase
+      test "a class can be registered for a symbol" do
+        registry = Type::Registry.new
+        registry.register(:foo, ::String)
+        registry.register(:bar, ::Array)
 
-    test "a block can be registered" do
-      registry = Type::Registry.new
-      registry.register(:foo) do |*args|
-        [*args, "block for foo"]
+        assert_equal "", registry.lookup(:foo)
+        assert_equal [], registry.lookup(:bar)
       end
-      registry.register(:bar) do |*args|
-        [*args, "block for bar"]
+
+      test "a block can be registered" do
+        registry = Type::Registry.new
+        registry.register(:foo) do |*args|
+          [*args, "block for foo"]
+        end
+        registry.register(:bar) do |*args|
+          [*args, "block for bar"]
+        end
+
+        assert_equal [:foo, 1, "block for foo"], registry.lookup(:foo, 1)
+        assert_equal [:foo, 2, "block for foo"], registry.lookup(:foo, 2)
+        assert_equal [:bar, 1, 2, 3, "block for bar"], registry.lookup(:bar, 1, 2, 3)
       end
 
-      assert_equal [:foo, 1, "block for foo"], registry.lookup(:foo, 1)
-      assert_equal [:foo, 2, "block for foo"], registry.lookup(:foo, 2)
-      assert_equal [:bar, 1, 2, 3, "block for bar"], registry.lookup(:bar, 1, 2, 3)
-    end
+      test "a reasonable error is given when no type is found" do
+        registry = Type::Registry.new
 
-    test "a reasonable error is given when no type is found" do
-      registry = Type::Registry.new
+        e = assert_raises(ArgumentError) do
+          registry.lookup(:foo)
+        end
 
-      e = assert_raises(ArgumentError) do
-        registry.lookup(:foo)
+        assert_equal "Unknown type :foo", e.message
       end
-
-      assert_equal "Unknown type :foo", e.message
     end
   end
 end
diff --git a/activemodel/test/cases/type/string_test.rb b/activemodel/test/cases/type/string_test.rb
index 7b25a1ef74..825c8bb246 100644
--- a/activemodel/test/cases/type/string_test.rb
+++ b/activemodel/test/cases/type/string_test.rb
@@ -1,27 +1,38 @@
+# frozen_string_literal: true
+
 require "cases/helper"
-require "active_model/type"
 
 module ActiveModel
-  class StringTypeTest < ActiveModel::TestCase
-    test "type casting" do
-      type = Type::String.new
-      assert_equal "t", type.cast(true)
-      assert_equal "f", type.cast(false)
-      assert_equal "123", type.cast(123)
-    end
+  module Type
+    class StringTest < ActiveModel::TestCase
+      test "type casting" do
+        type = Type::String.new
+        assert_equal "t", type.cast(true)
+        assert_equal "f", type.cast(false)
+        assert_equal "123", type.cast(123)
+      end
 
-    test "immutable strings are not duped coming out" do
-      s = "foo"
-      type = Type::ImmutableString.new
-      assert_same s, type.cast(s)
-      assert_same s, type.deserialize(s)
-    end
+      test "cast strings are mutable" do
+        type = Type::String.new
+
+        s = "foo".dup
+        assert_equal false, type.cast(s).frozen?
+        assert_equal false, s.frozen?
+
+        f = "foo".freeze
+        assert_equal false, type.cast(f).frozen?
+        assert_equal true, f.frozen?
+      end
+
+      test "values are duped coming out" do
+        type = Type::String.new
 
-    test "values are duped coming out" do
-      s = "foo"
-      type = Type::String.new
-      assert_not_same s, type.cast(s)
-      assert_not_same s, type.deserialize(s)
+        s = "foo"
+        assert_not_same s, type.cast(s)
+        assert_equal s, type.cast(s)
+        assert_not_same s, type.deserialize(s)
+        assert_equal s, type.deserialize(s)
+      end
     end
   end
 end
diff --git a/activemodel/test/cases/type/time_test.rb b/activemodel/test/cases/type/time_test.rb
new file mode 100644
index 0000000000..f7102d1e97
--- /dev/null
+++ b/activemodel/test/cases/type/time_test.rb
@@ -0,0 +1,22 @@
+# frozen_string_literal: true
+
+require "cases/helper"
+
+module ActiveModel
+  module Type
+    class TimeTest < ActiveModel::TestCase
+      def test_type_cast_time
+        type = Type::Time.new
+        assert_nil type.cast(nil)
+        assert_nil type.cast("")
+        assert_nil type.cast("ABC")
+
+        time_string = ::Time.now.utc.strftime("%T")
+        assert_equal time_string, type.cast(time_string).strftime("%T")
+
+        assert_equal ::Time.utc(2000,  1,  1, 16, 45, 54), type.cast("2015-06-13T19:45:54+03:00")
+        assert_equal ::Time.utc(1999, 12, 31, 21,  7,  8), type.cast("06:07:08+09:00")
+      end
+    end
+  end
+end
diff --git a/activemodel/test/cases/type/value_test.rb b/activemodel/test/cases/type/value_test.rb
new file mode 100644
index 0000000000..55b5d9d584
--- /dev/null
+++ b/activemodel/test/cases/type/value_test.rb
@@ -0,0 +1,15 @@
+# frozen_string_literal: true
+
+require "cases/helper"
+
+module ActiveModel
+  module Type
+    class ValueTest < ActiveModel::TestCase
+      def test_type_equality
+        assert_equal Type::Value.new, Type::Value.new
+        assert_not_equal Type::Value.new, Type::Integer.new
+        assert_not_equal Type::Value.new(precision: 1), Type::Value.new(precision: 2)
+      end
+    end
+  end
+end
diff --git a/activemodel/test/cases/types_test.rb b/activemodel/test/cases/types_test.rb
deleted file mode 100644
index 558c56f157..0000000000
--- a/activemodel/test/cases/types_test.rb
+++ /dev/null
@@ -1,125 +0,0 @@
-require "cases/helper"
-require "active_model/type"
-require "active_support/core_ext/numeric/time"
-
-module ActiveModel
-  class TypesTest < ActiveModel::TestCase
-    def test_type_cast_boolean
-      type = Type::Boolean.new
-      assert type.cast('').nil?
-      assert type.cast(nil).nil?
-
-      assert type.cast(true)
-      assert type.cast(1)
-      assert type.cast('1')
-      assert type.cast('t')
-      assert type.cast('T')
-      assert type.cast('true')
-      assert type.cast('TRUE')
-      assert type.cast('on')
-      assert type.cast('ON')
-      assert type.cast(' ')
-      assert type.cast("\u3000\r\n")
-      assert type.cast("\u0000")
-      assert type.cast('SOMETHING RANDOM')
-
-      # explicitly check for false vs nil
-      assert_equal false, type.cast(false)
-      assert_equal false, type.cast(0)
-      assert_equal false, type.cast('0')
-      assert_equal false, type.cast('f')
-      assert_equal false, type.cast('F')
-      assert_equal false, type.cast('false')
-      assert_equal false, type.cast('FALSE')
-      assert_equal false, type.cast('off')
-      assert_equal false, type.cast('OFF')
-    end
-
-    def test_type_cast_float
-      type = Type::Float.new
-      assert_equal 1.0, type.cast("1")
-    end
-
-    def test_changing_float
-      type = Type::Float.new
-
-      assert type.changed?(5.0, 5.0, '5wibble')
-      assert_not type.changed?(5.0, 5.0, '5')
-      assert_not type.changed?(5.0, 5.0, '5.0')
-      assert_not type.changed?(nil, nil, nil)
-    end
-
-    def test_type_cast_binary
-      type = Type::Binary.new
-      assert_equal nil, type.cast(nil)
-      assert_equal "1", type.cast("1")
-      assert_equal 1, type.cast(1)
-    end
-
-    def test_type_cast_time
-      type = Type::Time.new
-      assert_equal nil, type.cast(nil)
-      assert_equal nil, type.cast('')
-      assert_equal nil, type.cast('ABC')
-
-      time_string = Time.now.utc.strftime("%T")
-      assert_equal time_string, type.cast(time_string).strftime("%T")
-
-      assert_equal ::Time.utc(2000,  1,  1, 16, 45, 54), type.cast('2015-06-13T19:45:54+03:00')
-      assert_equal ::Time.utc(1999, 12, 31, 21,  7,  8), type.cast('06:07:08+09:00')
-    end
-
-    def test_type_cast_datetime_and_timestamp
-      type = Type::DateTime.new
-      assert_equal nil, type.cast(nil)
-      assert_equal nil, type.cast('')
-      assert_equal nil, type.cast('  ')
-      assert_equal nil, type.cast('ABC')
-
-      datetime_string = Time.now.utc.strftime("%FT%T")
-      assert_equal datetime_string, type.cast(datetime_string).strftime("%FT%T")
-    end
-
-    def test_type_cast_date
-      type = Type::Date.new
-      assert_equal nil, type.cast(nil)
-      assert_equal nil, type.cast('')
-      assert_equal nil, type.cast(' ')
-      assert_equal nil, type.cast('ABC')
-
-      date_string = Time.now.utc.strftime("%F")
-      assert_equal date_string, type.cast(date_string).strftime("%F")
-    end
-
-    def test_type_cast_duration_to_integer
-      type = Type::Integer.new
-      assert_equal 1800, type.cast(30.minutes)
-      assert_equal 7200, type.cast(2.hours)
-    end
-
-    def test_string_to_time_with_timezone
-      ["UTC", "US/Eastern"].each do |zone|
-        with_timezone_config default: zone do
-          type = Type::DateTime.new
-          assert_equal Time.utc(2013, 9, 4, 0, 0, 0), type.cast("Wed, 04 Sep 2013 03:00:00 EAT")
-        end
-      end
-    end
-
-    def test_type_equality
-      assert_equal Type::Value.new, Type::Value.new
-      assert_not_equal Type::Value.new, Type::Integer.new
-      assert_not_equal Type::Value.new(precision: 1), Type::Value.new(precision: 2)
-    end
-
-    private
-
-    def with_timezone_config(default:)
-      old_zone_default = ::Time.zone_default
-      ::Time.zone_default = ::Time.find_zone(default)
-      yield
-    ensure
-      ::Time.zone_default = old_zone_default
-    end
-  end
-end
diff --git a/activemodel/test/cases/validations/absence_validation_test.rb b/activemodel/test/cases/validations/absence_validation_test.rb
index 9cbc77dfb5..801577474a 100644
--- a/activemodel/test/cases/validations/absence_validation_test.rb
+++ b/activemodel/test/cases/validations/absence_validation_test.rb
@@ -1,7 +1,9 @@
-require 'cases/helper'
-require 'models/topic'
-require 'models/person'
-require 'models/custom_reader'
+# frozen_string_literal: true
+
+require "cases/helper"
+require "models/topic"
+require "models/person"
+require "models/custom_reader"
 
 class AbsenceValidationTest < ActiveModel::TestCase
   teardown do
@@ -19,7 +21,7 @@ class AbsenceValidationTest < ActiveModel::TestCase
     assert_equal ["must be blank"], t.errors[:title]
     assert_equal ["must be blank"], t.errors[:content]
     t.title = ""
-    t.content  = "something"
+    t.content = "something"
     assert t.invalid?
     assert_equal ["must be blank"], t.errors[:content]
     assert_equal [], t.errors[:title]
diff --git a/activemodel/test/cases/validations/acceptance_validation_test.rb b/activemodel/test/cases/validations/acceptance_validation_test.rb
index d3995ad5af..c5f54b1868 100644
--- a/activemodel/test/cases/validations/acceptance_validation_test.rb
+++ b/activemodel/test/cases/validations/acceptance_validation_test.rb
@@ -1,11 +1,12 @@
-require 'cases/helper'
+# frozen_string_literal: true
 
-require 'models/topic'
-require 'models/reply'
-require 'models/person'
+require "cases/helper"
 
-class AcceptanceValidationTest < ActiveModel::TestCase
+require "models/topic"
+require "models/reply"
+require "models/person"
 
+class AcceptanceValidationTest < ActiveModel::TestCase
   def teardown
     Topic.clear_validators!
   end
@@ -20,7 +21,7 @@ class AcceptanceValidationTest < ActiveModel::TestCase
   def test_terms_of_service_agreement
     Topic.validates_acceptance_of(:terms_of_service)
 
-    t = Topic.new("title" => "We should be confirmed","terms_of_service" => "")
+    t = Topic.new("title" => "We should be confirmed", "terms_of_service" => "")
     assert t.invalid?
     assert_equal ["must be accepted"], t.errors[:terms_of_service]
 
@@ -31,7 +32,7 @@ class AcceptanceValidationTest < ActiveModel::TestCase
   def test_eula
     Topic.validates_acceptance_of(:eula, message: "must be abided")
 
-    t = Topic.new("title" => "We should be confirmed","eula" => "")
+    t = Topic.new("title" => "We should be confirmed", "eula" => "")
     assert t.invalid?
     assert_equal ["must be abided"], t.errors[:eula]
 
diff --git a/activemodel/test/cases/validations/callbacks_test.rb b/activemodel/test/cases/validations/callbacks_test.rb
index 75eb18e795..ff3cf61746 100644
--- a/activemodel/test/cases/validations/callbacks_test.rb
+++ b/activemodel/test/cases/validations/callbacks_test.rb
@@ -1,4 +1,6 @@
-require 'cases/helper'
+# frozen_string_literal: true
+
+require "cases/helper"
 
 class Dog
   include ActiveModel::Validations
@@ -15,37 +17,37 @@ class DogWithMethodCallbacks < Dog
   before_validation :set_before_validation_marker
   after_validation :set_after_validation_marker
 
-  def set_before_validation_marker; self.history << 'before_validation_marker'; end
-  def set_after_validation_marker;  self.history << 'after_validation_marker' ; end
+  def set_before_validation_marker; history << "before_validation_marker"; end
+  def set_after_validation_marker;  history << "after_validation_marker" ; end
 end
 
 class DogValidatorsAreProc < Dog
-  before_validation { self.history << 'before_validation_marker' }
-  after_validation  { self.history << 'after_validation_marker' }
+  before_validation { history << "before_validation_marker" }
+  after_validation  { history << "after_validation_marker" }
 end
 
 class DogWithTwoValidators < Dog
-  before_validation { self.history << 'before_validation_marker1' }
-  before_validation { self.history << 'before_validation_marker2' }
+  before_validation { history << "before_validation_marker1" }
+  before_validation { history << "before_validation_marker2" }
 end
 
-class DogDeprecatedBeforeValidatorReturningFalse < Dog
+class DogBeforeValidatorReturningFalse < Dog
   before_validation { false }
-  before_validation { self.history << 'before_validation_marker2' }
+  before_validation { history << "before_validation_marker2" }
 end
 
 class DogBeforeValidatorThrowingAbort < Dog
   before_validation { throw :abort }
-  before_validation { self.history << 'before_validation_marker2' }
+  before_validation { history << "before_validation_marker2" }
 end
 
 class DogAfterValidatorReturningFalse < Dog
   after_validation { false }
-  after_validation { self.history << 'after_validation_marker' }
+  after_validation { history << "after_validation_marker" }
 end
 
 class DogWithMissingName < Dog
-  before_validation { self.history << 'before_validation_marker' }
+  before_validation { history << "before_validation_marker" }
   validates_presence_of :name
 end
 
@@ -53,8 +55,20 @@ class DogValidatorWithOnCondition < Dog
   before_validation :set_before_validation_marker, on: :create
   after_validation :set_after_validation_marker, on: :create
 
-  def set_before_validation_marker; self.history << 'before_validation_marker'; end
-  def set_after_validation_marker;  self.history << 'after_validation_marker' ; end
+  def set_before_validation_marker; history << "before_validation_marker"; end
+  def set_after_validation_marker;  history << "after_validation_marker" ; end
+end
+
+class DogValidatorWithOnMultipleCondition < Dog
+  before_validation :set_before_validation_marker_on_context_a, on: :context_a
+  before_validation :set_before_validation_marker_on_context_b, on: :context_b
+  after_validation :set_after_validation_marker_on_context_a, on: :context_a
+  after_validation :set_after_validation_marker_on_context_b, on: :context_b
+
+  def set_before_validation_marker_on_context_a; history << "before_validation_marker on context_a"; end
+  def set_before_validation_marker_on_context_b; history << "before_validation_marker on context_b"; end
+  def set_after_validation_marker_on_context_a;  history << "after_validation_marker on context_a" ; end
+  def set_after_validation_marker_on_context_b;  history << "after_validation_marker on context_b" ; end
 end
 
 class DogValidatorWithIfCondition < Dog
@@ -64,16 +78,14 @@ class DogValidatorWithIfCondition < Dog
   after_validation :set_after_validation_marker1, if: -> { true }
   after_validation :set_after_validation_marker2, if: -> { false }
 
-  def set_before_validation_marker1; self.history << 'before_validation_marker1'; end
-  def set_before_validation_marker2; self.history << 'before_validation_marker2' ; end
+  def set_before_validation_marker1; history << "before_validation_marker1"; end
+  def set_before_validation_marker2; history << "before_validation_marker2" ; end
 
-  def set_after_validation_marker1; self.history << 'after_validation_marker1'; end
-  def set_after_validation_marker2; self.history << 'after_validation_marker2' ; end
+  def set_after_validation_marker1; history << "after_validation_marker1"; end
+  def set_after_validation_marker2; history << "after_validation_marker2" ; end
 end
 
-
 class CallbacksWithMethodNamesShouldBeCalled < ActiveModel::TestCase
-
   def test_if_condition_is_respected_for_before_validation
     d = DogValidatorWithIfCondition.new
     d.valid?
@@ -98,22 +110,53 @@ class CallbacksWithMethodNamesShouldBeCalled < ActiveModel::TestCase
     assert_equal [], d.history
   end
 
+  def test_on_multiple_condition_is_respected_for_validation_with_matching_context
+    d = DogValidatorWithOnMultipleCondition.new
+    d.valid?(:context_a)
+    assert_equal ["before_validation_marker on context_a", "after_validation_marker on context_a"], d.history
+
+    d = DogValidatorWithOnMultipleCondition.new
+    d.valid?(:context_b)
+    assert_equal ["before_validation_marker on context_b", "after_validation_marker on context_b"], d.history
+
+    d = DogValidatorWithOnMultipleCondition.new
+    d.valid?([:context_a, :context_b])
+    assert_equal([
+      "before_validation_marker on context_a",
+      "before_validation_marker on context_b",
+      "after_validation_marker on context_a",
+      "after_validation_marker on context_b"
+    ], d.history)
+  end
+
+  def test_on_multiple_condition_is_respected_for_validation_without_matching_context
+    d = DogValidatorWithOnMultipleCondition.new
+    d.valid?(:save)
+    assert_equal [], d.history
+  end
+
+  def test_on_multiple_condition_is_respected_for_validation_without_context
+    d = DogValidatorWithOnMultipleCondition.new
+    d.valid?
+    assert_equal [], d.history
+  end
+
   def test_before_validation_and_after_validation_callbacks_should_be_called
     d = DogWithMethodCallbacks.new
     d.valid?
-    assert_equal ['before_validation_marker', 'after_validation_marker'], d.history
+    assert_equal ["before_validation_marker", "after_validation_marker"], d.history
   end
 
   def test_before_validation_and_after_validation_callbacks_should_be_called_with_proc
     d = DogValidatorsAreProc.new
     d.valid?
-    assert_equal ['before_validation_marker', 'after_validation_marker'], d.history
+    assert_equal ["before_validation_marker", "after_validation_marker"], d.history
   end
 
   def test_before_validation_and_after_validation_callbacks_should_be_called_in_declared_order
     d = DogWithTwoValidators.new
     d.valid?
-    assert_equal ['before_validation_marker1', 'before_validation_marker2'], d.history
+    assert_equal ["before_validation_marker1", "before_validation_marker2"], d.history
   end
 
   def test_further_callbacks_should_not_be_called_if_before_validation_throws_abort
@@ -123,26 +166,23 @@ class CallbacksWithMethodNamesShouldBeCalled < ActiveModel::TestCase
     assert_equal false, output
   end
 
-  def test_deprecated_further_callbacks_should_not_be_called_if_before_validation_returns_false
-    d = DogDeprecatedBeforeValidatorReturningFalse.new
-    assert_deprecated do
-      output = d.valid?
-      assert_equal [], d.history
-      assert_equal false, output
-    end
+  def test_further_callbacks_should_be_called_if_before_validation_returns_false
+    d = DogBeforeValidatorReturningFalse.new
+    output = d.valid?
+    assert_equal ["before_validation_marker2"], d.history
+    assert_equal true, output
   end
 
   def test_further_callbacks_should_be_called_if_after_validation_returns_false
     d = DogAfterValidatorReturningFalse.new
     d.valid?
-    assert_equal ['after_validation_marker'], d.history
+    assert_equal ["after_validation_marker"], d.history
   end
 
   def test_validation_test_should_be_done
     d = DogWithMissingName.new
     output = d.valid?
-    assert_equal ['before_validation_marker'], d.history
+    assert_equal ["before_validation_marker"], d.history
     assert_equal false, output
   end
-
 end
diff --git a/activemodel/test/cases/validations/conditional_validation_test.rb b/activemodel/test/cases/validations/conditional_validation_test.rb
index 296d3b4407..caea8b65ef 100644
--- a/activemodel/test/cases/validations/conditional_validation_test.rb
+++ b/activemodel/test/cases/validations/conditional_validation_test.rb
@@ -1,9 +1,10 @@
-require 'cases/helper'
+# frozen_string_literal: true
 
-require 'models/topic'
+require "cases/helper"
 
-class ConditionalValidationTest < ActiveModel::TestCase
+require "models/topic"
 
+class ConditionalValidationTest < ActiveModel::TestCase
   def teardown
     Topic.clear_validators!
   end
@@ -17,6 +18,22 @@ class ConditionalValidationTest < ActiveModel::TestCase
     assert_equal ["hoo 5"], t.errors["title"]
   end
 
+  def test_if_validation_using_array_of_true_methods
+    Topic.validates_length_of(:title, maximum: 5, too_long: "hoo %{count}", if: [:condition_is_true, :condition_is_true])
+    t = Topic.new("title" => "uhohuhoh", "content" => "whatever")
+    assert t.invalid?
+    assert t.errors[:title].any?
+    assert_equal ["hoo 5"], t.errors["title"]
+  end
+
+  def test_unless_validation_using_array_of_false_methods
+    Topic.validates_length_of(:title, maximum: 5, too_long: "hoo %{count}", unless: [:condition_is_false, :condition_is_false])
+    t = Topic.new("title" => "uhohuhoh", "content" => "whatever")
+    assert t.invalid?
+    assert t.errors[:title].any?
+    assert_equal ["hoo 5"], t.errors["title"]
+  end
+
   def test_unless_validation_using_method_true
     # When the method returns true
     Topic.validates_length_of(:title, maximum: 5, too_long: "hoo %{count}", unless: :condition_is_true)
@@ -25,51 +42,31 @@ class ConditionalValidationTest < ActiveModel::TestCase
     assert_empty t.errors[:title]
   end
 
-  def test_if_validation_using_method_false
-    # When the method returns false
-    Topic.validates_length_of(:title, maximum: 5, too_long: "hoo %{count}", if: :condition_is_true_but_its_not)
+  def test_if_validation_using_array_of_true_and_false_methods
+    Topic.validates_length_of(:title, maximum: 5, too_long: "hoo %{count}", if: [:condition_is_true, :condition_is_false])
     t = Topic.new("title" => "uhohuhoh", "content" => "whatever")
     assert t.valid?
     assert_empty t.errors[:title]
   end
 
-  def test_unless_validation_using_method_false
-    # When the method returns false
-    Topic.validates_length_of(:title, maximum: 5, too_long: "hoo %{count}", unless: :condition_is_true_but_its_not)
-    t = Topic.new("title" => "uhohuhoh", "content" => "whatever")
-    assert t.invalid?
-    assert t.errors[:title].any?
-    assert_equal ["hoo 5"], t.errors["title"]
-  end
-
-  def test_if_validation_using_string_true
-    # When the evaluated string returns true
-    Topic.validates_length_of(:title, maximum: 5, too_long: "hoo %{count}", if: "a = 1; a == 1")
-    t = Topic.new("title" => "uhohuhoh", "content" => "whatever")
-    assert t.invalid?
-    assert t.errors[:title].any?
-    assert_equal ["hoo 5"], t.errors["title"]
-  end
-
-  def test_unless_validation_using_string_true
-    # When the evaluated string returns true
-    Topic.validates_length_of(:title, maximum: 5, too_long: "hoo %{count}", unless: "a = 1; a == 1")
+  def test_unless_validation_using_array_of_true_and_felse_methods
+    Topic.validates_length_of(:title, maximum: 5, too_long: "hoo %{count}", unless: [:condition_is_true, :condition_is_false])
     t = Topic.new("title" => "uhohuhoh", "content" => "whatever")
     assert t.valid?
     assert_empty t.errors[:title]
   end
 
-  def test_if_validation_using_string_false
-    # When the evaluated string returns false
-    Topic.validates_length_of(:title, maximum: 5, too_long: "hoo %{count}", if: "false")
+  def test_if_validation_using_method_false
+    # When the method returns false
+    Topic.validates_length_of(:title, maximum: 5, too_long: "hoo %{count}", if: :condition_is_false)
     t = Topic.new("title" => "uhohuhoh", "content" => "whatever")
     assert t.valid?
     assert_empty t.errors[:title]
   end
 
-  def test_unless_validation_using_string_false
-    # When the evaluated string returns false
-    Topic.validates_length_of(:title, maximum: 5, too_long: "hoo %{count}", unless: "false")
+  def test_unless_validation_using_method_false
+    # When the method returns false
+    Topic.validates_length_of(:title, maximum: 5, too_long: "hoo %{count}", unless: :condition_is_false)
     t = Topic.new("title" => "uhohuhoh", "content" => "whatever")
     assert t.invalid?
     assert t.errors[:title].any?
@@ -98,7 +95,7 @@ class ConditionalValidationTest < ActiveModel::TestCase
   def test_if_validation_using_block_false
     # When the block returns false
     Topic.validates_length_of(:title, maximum: 5, too_long: "hoo %{count}",
-      if: Proc.new { |r| r.title != "uhohuhoh"})
+      if: Proc.new { |r| r.title != "uhohuhoh" })
     t = Topic.new("title" => "uhohuhoh", "content" => "whatever")
     assert t.valid?
     assert_empty t.errors[:title]
@@ -107,32 +104,25 @@ class ConditionalValidationTest < ActiveModel::TestCase
   def test_unless_validation_using_block_false
     # When the block returns false
     Topic.validates_length_of(:title, maximum: 5, too_long: "hoo %{count}",
-      unless: Proc.new { |r| r.title != "uhohuhoh"} )
+      unless: Proc.new { |r| r.title != "uhohuhoh" })
     t = Topic.new("title" => "uhohuhoh", "content" => "whatever")
     assert t.invalid?
     assert t.errors[:title].any?
     assert_equal ["hoo 5"], t.errors["title"]
   end
 
-  # previous implementation of validates_presence_of eval'd the
-  # string with the wrong binding, this regression test is to
-  # ensure that it works correctly
-  def test_validation_with_if_as_string
-    Topic.validates_presence_of(:title)
-    Topic.validates_presence_of(:author_name, if: "title.to_s.match('important')")
-
-    t = Topic.new
-    assert t.invalid?, "A topic without a title should not be valid"
-    assert_empty t.errors[:author_name], "A topic without an 'important' title should not require an author"
-
-    t.title = "Just a title"
-    assert t.valid?, "A topic with a basic title should be valid"
-
-    t.title = "A very important title"
-    assert t.invalid?, "A topic with an important title, but without an author, should not be valid"
-    assert t.errors[:author_name].any?, "A topic with an 'important' title should require an author"
+  def test_validation_using_conbining_if_true_and_unless_true_conditions
+    Topic.validates_length_of(:title, maximum: 5, too_long: "hoo %{count}", if: :condition_is_true, unless: :condition_is_true)
+    t = Topic.new("title" => "uhohuhoh", "content" => "whatever")
+    assert t.valid?
+    assert_empty t.errors[:title]
+  end
 
-    t.author_name = "Hubert J. Farnsworth"
-    assert t.valid?, "A topic with an important title and author should be valid"
+  def test_validation_using_conbining_if_true_and_unless_false_conditions
+    Topic.validates_length_of(:title, maximum: 5, too_long: "hoo %{count}", if: :condition_is_true, unless: :condition_is_false)
+    t = Topic.new("title" => "uhohuhoh", "content" => "whatever")
+    assert t.invalid?
+    assert t.errors[:title].any?
+    assert_equal ["hoo 5"], t.errors["title"]
   end
 end
diff --git a/activemodel/test/cases/validations/confirmation_validation_test.rb b/activemodel/test/cases/validations/confirmation_validation_test.rb
index c56bf1c0ad..8b2c65289b 100644
--- a/activemodel/test/cases/validations/confirmation_validation_test.rb
+++ b/activemodel/test/cases/validations/confirmation_validation_test.rb
@@ -1,10 +1,11 @@
-require 'cases/helper'
+# frozen_string_literal: true
 
-require 'models/topic'
-require 'models/person'
+require "cases/helper"
 
-class ConfirmationValidationTest < ActiveModel::TestCase
+require "models/topic"
+require "models/person"
 
+class ConfirmationValidationTest < ActiveModel::TestCase
   def teardown
     Topic.clear_validators!
   end
@@ -29,13 +30,26 @@ class ConfirmationValidationTest < ActiveModel::TestCase
   def test_title_confirmation
     Topic.validates_confirmation_of(:title)
 
-    t = Topic.new("title" => "We should be confirmed","title_confirmation" => "")
+    t = Topic.new("title" => "We should be confirmed", "title_confirmation" => "")
     assert t.invalid?
 
     t.title_confirmation = "We should be confirmed"
     assert t.valid?
   end
 
+  def test_validates_confirmation_of_with_boolean_attribute
+    Topic.validates_confirmation_of(:approved)
+
+    t = Topic.new(approved: true, approved_confirmation: nil)
+    assert t.valid?
+
+    t.approved_confirmation = false
+    assert t.invalid?
+
+    t.approved_confirmation = true
+    assert t.valid?
+  end
+
   def test_validates_confirmation_of_for_ruby_class
     Person.validates_confirmation_of :karma
 
@@ -56,14 +70,13 @@ class ConfirmationValidationTest < ActiveModel::TestCase
       @old_load_path, @old_backend = I18n.load_path.dup, I18n.backend
       I18n.load_path.clear
       I18n.backend = I18n::Backend::Simple.new
-      I18n.backend.store_translations('en', {
+      I18n.backend.store_translations("en",
         errors: { messages: { confirmation: "doesn't match %{attribute}" } },
-        activemodel: { attributes: { topic: { title: 'Test Title'} } }
-      })
+        activemodel: { attributes: { topic: { title: "Test Title" } } })
 
       Topic.validates_confirmation_of(:title)
 
-      t = Topic.new("title" => "We should be confirmed","title_confirmation" => "")
+      t = Topic.new("title" => "We should be confirmed", "title_confirmation" => "")
       assert t.invalid?
       assert_equal ["doesn't match Test Title"], t.errors[:title_confirmation]
     ensure
diff --git a/activemodel/test/cases/validations/exclusion_validation_test.rb b/activemodel/test/cases/validations/exclusion_validation_test.rb
index 005bc15df5..68d611e904 100644
--- a/activemodel/test/cases/validations/exclusion_validation_test.rb
+++ b/activemodel/test/cases/validations/exclusion_validation_test.rb
@@ -1,11 +1,12 @@
-require 'cases/helper'
-require 'active_support/core_ext/numeric/time'
+# frozen_string_literal: true
 
-require 'models/topic'
-require 'models/person'
+require "cases/helper"
+require "active_support/core_ext/numeric/time"
 
-class ExclusionValidationTest < ActiveModel::TestCase
+require "models/topic"
+require "models/person"
 
+class ExclusionValidationTest < ActiveModel::TestCase
   def teardown
     Topic.clear_validators!
   end
@@ -68,8 +69,8 @@ class ExclusionValidationTest < ActiveModel::TestCase
   def test_validates_exclusion_of_with_range
     Topic.validates_exclusion_of :content, in: ("a".."g")
 
-    assert Topic.new(content: 'g').invalid?
-    assert Topic.new(content: 'h').valid?
+    assert Topic.new(content: "g").invalid?
+    assert Topic.new(content: "h").valid?
   end
 
   def test_validates_exclusion_of_with_time_range
diff --git a/activemodel/test/cases/validations/format_validation_test.rb b/activemodel/test/cases/validations/format_validation_test.rb
index ea4c2ee7df..3ddda2154a 100644
--- a/activemodel/test/cases/validations/format_validation_test.rb
+++ b/activemodel/test/cases/validations/format_validation_test.rb
@@ -1,10 +1,11 @@
-require 'cases/helper'
+# frozen_string_literal: true
 
-require 'models/topic'
-require 'models/person'
+require "cases/helper"
 
-class PresenceValidationTest < ActiveModel::TestCase
+require "models/topic"
+require "models/person"
 
+class PresenceValidationTest < ActiveModel::TestCase
   def teardown
     Topic.clear_validators!
   end
@@ -63,7 +64,7 @@ class PresenceValidationTest < ActiveModel::TestCase
 
   def test_validate_format_with_formatted_message
     Topic.validates_format_of(:title, with: /\AValid Title\z/, message: "can't be %{value}")
-    t = Topic.new(title: 'Invalid title')
+    t = Topic.new(title: "Invalid title")
     assert t.invalid?
     assert_equal ["can't be Invalid title"], t.errors[:title]
   end
@@ -108,7 +109,7 @@ class PresenceValidationTest < ActiveModel::TestCase
   end
 
   def test_validates_format_of_with_lambda
-    Topic.validates_format_of :content, with: lambda { |topic| topic.title == "digit" ? /\A\d+\Z/ : /\A\S+\Z/ }
+    Topic.validates_format_of :content, with: lambda { |topic| topic.title == "digit" ? /\A\d+\z/ : /\A\S+\z/ }
 
     t = Topic.new
     t.title = "digit"
@@ -120,7 +121,7 @@ class PresenceValidationTest < ActiveModel::TestCase
   end
 
   def test_validates_format_of_without_lambda
-    Topic.validates_format_of :content, without: lambda { |topic| topic.title == "characters" ? /\A\d+\Z/ : /\A\S+\Z/ }
+    Topic.validates_format_of :content, without: lambda { |topic| topic.title == "characters" ? /\A\d+\z/ : /\A\S+\z/ }
 
     t = Topic.new
     t.title = "characters"
@@ -132,7 +133,7 @@ class PresenceValidationTest < ActiveModel::TestCase
   end
 
   def test_validates_format_of_for_ruby_class
-    Person.validates_format_of :karma, with: /\A\d+\Z/
+    Person.validates_format_of :karma, with: /\A\d+\z/
 
     p = Person.new
     p.karma = "Pixies"
diff --git a/activemodel/test/cases/validations/i18n_generate_message_validation_test.rb b/activemodel/test/cases/validations/i18n_generate_message_validation_test.rb
index da63df9152..d3e44945db 100644
--- a/activemodel/test/cases/validations/i18n_generate_message_validation_test.rb
+++ b/activemodel/test/cases/validations/i18n_generate_message_validation_test.rb
@@ -1,6 +1,8 @@
+# frozen_string_literal: true
+
 require "cases/helper"
 
-require 'models/person'
+require "models/person"
 
 class I18nGenerateMessageValidationTest < ActiveModel::TestCase
   def setup
@@ -10,29 +12,29 @@ class I18nGenerateMessageValidationTest < ActiveModel::TestCase
 
   # validates_inclusion_of: generate_message(attr_name, :inclusion, message: custom_message, value: value)
   def test_generate_message_inclusion_with_default_message
-    assert_equal 'is not included in the list', @person.errors.generate_message(:title, :inclusion, value: 'title')
+    assert_equal "is not included in the list", @person.errors.generate_message(:title, :inclusion, value: "title")
   end
 
   def test_generate_message_inclusion_with_custom_message
-    assert_equal 'custom message title', @person.errors.generate_message(:title, :inclusion, message: 'custom message %{value}', value: 'title')
+    assert_equal "custom message title", @person.errors.generate_message(:title, :inclusion, message: "custom message %{value}", value: "title")
   end
 
   # validates_exclusion_of: generate_message(attr_name, :exclusion, message: custom_message, value: value)
   def test_generate_message_exclusion_with_default_message
-    assert_equal 'is reserved', @person.errors.generate_message(:title, :exclusion, value: 'title')
+    assert_equal "is reserved", @person.errors.generate_message(:title, :exclusion, value: "title")
   end
 
   def test_generate_message_exclusion_with_custom_message
-    assert_equal 'custom message title', @person.errors.generate_message(:title, :exclusion, message: 'custom message %{value}', value: 'title')
+    assert_equal "custom message title", @person.errors.generate_message(:title, :exclusion, message: "custom message %{value}", value: "title")
   end
 
   # validates_format_of:  generate_message(attr_name, :invalid, message: custom_message, value: value)
   def test_generate_message_invalid_with_default_message
-    assert_equal 'is invalid', @person.errors.generate_message(:title, :invalid, value: 'title')
+    assert_equal "is invalid", @person.errors.generate_message(:title, :invalid, value: "title")
   end
 
   def test_generate_message_invalid_with_custom_message
-    assert_equal 'custom message title', @person.errors.generate_message(:title, :invalid, message: 'custom message %{value}', value: 'title')
+    assert_equal "custom message title", @person.errors.generate_message(:title, :invalid, message: "custom message %{value}", value: "title")
   end
 
   # validates_confirmation_of: generate_message(attr_name, :confirmation, message: custom_message)
@@ -41,7 +43,7 @@ class I18nGenerateMessageValidationTest < ActiveModel::TestCase
   end
 
   def test_generate_message_confirmation_with_custom_message
-    assert_equal 'custom message', @person.errors.generate_message(:title, :confirmation, message: 'custom message')
+    assert_equal "custom message", @person.errors.generate_message(:title, :confirmation, message: "custom message")
   end
 
   # validates_acceptance_of: generate_message(attr_name, :accepted, message: custom_message)
@@ -50,7 +52,7 @@ class I18nGenerateMessageValidationTest < ActiveModel::TestCase
   end
 
   def test_generate_message_accepted_with_custom_message
-    assert_equal 'custom message', @person.errors.generate_message(:title, :accepted, message: 'custom message')
+    assert_equal "custom message", @person.errors.generate_message(:title, :accepted, message: "custom message")
   end
 
   # add_on_empty: generate_message(attr, :empty, message: custom_message)
@@ -59,7 +61,7 @@ class I18nGenerateMessageValidationTest < ActiveModel::TestCase
   end
 
   def test_generate_message_empty_with_custom_message
-    assert_equal 'custom message', @person.errors.generate_message(:title, :empty, message: 'custom message')
+    assert_equal "custom message", @person.errors.generate_message(:title, :empty, message: "custom message")
   end
 
   # validates_presence_of: generate_message(attr, :blank, message: custom_message)
@@ -68,7 +70,7 @@ class I18nGenerateMessageValidationTest < ActiveModel::TestCase
   end
 
   def test_generate_message_blank_with_custom_message
-    assert_equal 'custom message', @person.errors.generate_message(:title, :blank, message: 'custom message')
+    assert_equal "custom message", @person.errors.generate_message(:title, :blank, message: "custom message")
   end
 
   # validates_length_of: generate_message(attr, :too_long, message: custom_message, count: option_value.end)
@@ -81,7 +83,7 @@ class I18nGenerateMessageValidationTest < ActiveModel::TestCase
   end
 
   def test_generate_message_too_long_with_custom_message
-    assert_equal 'custom message 10', @person.errors.generate_message(:title, :too_long, message: 'custom message %{count}', count: 10)
+    assert_equal "custom message 10", @person.errors.generate_message(:title, :too_long, message: "custom message %{count}", count: 10)
   end
 
   # validates_length_of: generate_message(attr, :too_short, default: custom_message, count: option_value.begin)
@@ -94,7 +96,7 @@ class I18nGenerateMessageValidationTest < ActiveModel::TestCase
   end
 
   def test_generate_message_too_short_with_custom_message
-    assert_equal 'custom message 10', @person.errors.generate_message(:title, :too_short, message: 'custom message %{count}', count: 10)
+    assert_equal "custom message 10", @person.errors.generate_message(:title, :too_short, message: "custom message %{count}", count: 10)
   end
 
   # validates_length_of: generate_message(attr, :wrong_length, message: custom_message, count: option_value)
@@ -107,44 +109,44 @@ class I18nGenerateMessageValidationTest < ActiveModel::TestCase
   end
 
   def test_generate_message_wrong_length_with_custom_message
-    assert_equal 'custom message 10', @person.errors.generate_message(:title, :wrong_length, message: 'custom message %{count}', count: 10)
+    assert_equal "custom message 10", @person.errors.generate_message(:title, :wrong_length, message: "custom message %{count}", count: 10)
   end
 
   # validates_numericality_of: generate_message(attr_name, :not_a_number, value: raw_value, message: custom_message)
   def test_generate_message_not_a_number_with_default_message
-    assert_equal "is not a number", @person.errors.generate_message(:title, :not_a_number, value: 'title')
+    assert_equal "is not a number", @person.errors.generate_message(:title, :not_a_number, value: "title")
   end
 
   def test_generate_message_not_a_number_with_custom_message
-    assert_equal 'custom message title', @person.errors.generate_message(:title, :not_a_number, message: 'custom message %{value}', value: 'title')
+    assert_equal "custom message title", @person.errors.generate_message(:title, :not_a_number, message: "custom message %{value}", value: "title")
   end
 
   # validates_numericality_of: generate_message(attr_name, option, value: raw_value, default: custom_message)
   def test_generate_message_greater_than_with_default_message
-    assert_equal "must be greater than 10", @person.errors.generate_message(:title, :greater_than, value: 'title', count: 10)
+    assert_equal "must be greater than 10", @person.errors.generate_message(:title, :greater_than, value: "title", count: 10)
   end
 
   def test_generate_message_greater_than_or_equal_to_with_default_message
-    assert_equal "must be greater than or equal to 10", @person.errors.generate_message(:title, :greater_than_or_equal_to, value: 'title', count: 10)
+    assert_equal "must be greater than or equal to 10", @person.errors.generate_message(:title, :greater_than_or_equal_to, value: "title", count: 10)
   end
 
   def test_generate_message_equal_to_with_default_message
-    assert_equal "must be equal to 10", @person.errors.generate_message(:title, :equal_to, value: 'title', count: 10)
+    assert_equal "must be equal to 10", @person.errors.generate_message(:title, :equal_to, value: "title", count: 10)
   end
 
   def test_generate_message_less_than_with_default_message
-    assert_equal "must be less than 10", @person.errors.generate_message(:title, :less_than, value: 'title', count: 10)
+    assert_equal "must be less than 10", @person.errors.generate_message(:title, :less_than, value: "title", count: 10)
   end
 
   def test_generate_message_less_than_or_equal_to_with_default_message
-    assert_equal "must be less than or equal to 10", @person.errors.generate_message(:title, :less_than_or_equal_to, value: 'title', count: 10)
+    assert_equal "must be less than or equal to 10", @person.errors.generate_message(:title, :less_than_or_equal_to, value: "title", count: 10)
   end
 
   def test_generate_message_odd_with_default_message
-    assert_equal "must be odd", @person.errors.generate_message(:title, :odd, value: 'title', count: 10)
+    assert_equal "must be odd", @person.errors.generate_message(:title, :odd, value: "title", count: 10)
   end
 
   def test_generate_message_even_with_default_message
-    assert_equal "must be even", @person.errors.generate_message(:title, :even, value: 'title', count: 10)
+    assert_equal "must be even", @person.errors.generate_message(:title, :even, value: "title", count: 10)
   end
 end
diff --git a/activemodel/test/cases/validations/i18n_validation_test.rb b/activemodel/test/cases/validations/i18n_validation_test.rb
index 09d7226b5a..9cfe189d0e 100644
--- a/activemodel/test/cases/validations/i18n_validation_test.rb
+++ b/activemodel/test/cases/validations/i18n_validation_test.rb
@@ -1,8 +1,9 @@
+# frozen_string_literal: true
+
 require "cases/helper"
-require 'models/person'
+require "models/person"
 
 class I18nValidationTest < ActiveModel::TestCase
-
   def setup
     Person.clear_validators!
     @person = Person.new
@@ -10,7 +11,7 @@ class I18nValidationTest < ActiveModel::TestCase
     @old_load_path, @old_backend = I18n.load_path.dup, I18n.backend
     I18n.load_path.clear
     I18n.backend = I18n::Backend::Simple.new
-    I18n.backend.store_translations('en', errors: { messages: { custom: nil } })
+    I18n.backend.store_translations("en", errors: { messages: { custom: nil } })
   end
 
   def teardown
@@ -21,23 +22,23 @@ class I18nValidationTest < ActiveModel::TestCase
   end
 
   def test_full_message_encoding
-    I18n.backend.store_translations('en', errors: {
-      messages: { too_short: '猫舌' } })
+    I18n.backend.store_translations("en", errors: {
+      messages: { too_short: "猫舌" } })
     Person.validates_length_of :title, within: 3..5
     @person.valid?
-    assert_equal ['Title 猫舌'], @person.errors.full_messages
+    assert_equal ["Title 猫舌"], @person.errors.full_messages
   end
 
   def test_errors_full_messages_translates_human_attribute_name_for_model_attributes
-    @person.errors.add(:name, 'not found')
-    assert_called_with(Person, :human_attribute_name, [:name, default: 'Name'], returns: "Person's name") do
+    @person.errors.add(:name, "not found")
+    assert_called_with(Person, :human_attribute_name, [:name, default: "Name"], returns: "Person's name") do
       assert_equal ["Person's name not found"], @person.errors.full_messages
     end
   end
 
   def test_errors_full_messages_uses_format
-    I18n.backend.store_translations('en', errors: { format: "Field %{attribute} %{message}" })
-    @person.errors.add('name', 'empty')
+    I18n.backend.store_translations("en", errors: { format: "Field %{attribute} %{message}" })
+    @person.errors.add("name", "empty")
     assert_equal ["Field Name empty"], @person.errors.full_messages
   end
 
@@ -47,19 +48,19 @@ class I18nValidationTest < ActiveModel::TestCase
   # are used to generate tests to keep things DRY
   #
   COMMON_CASES = [
-  # [ case,                                validation_options,            generate_message_options]
+    # [ case,                              validation_options,            generate_message_options]
     [ "given no options",                  {},                            {}],
     [ "given custom message",              { message: "custom" },         { message: "custom" }],
-    [ "given if condition",                { if:                          lambda { true }},  {}],
-    [ "given unless condition",            { unless:                      lambda { false }}, {}],
+    [ "given if condition",                { if:                          lambda { true } },  {}],
+    [ "given unless condition",            { unless:                      lambda { false } }, {}],
     [ "given option that is not reserved", { format: "jpg" },             { format: "jpg" }]
   ]
 
   COMMON_CASES.each do |name, validation_options, generate_message_options|
     test "validates_confirmation_of on generated message #{name}" do
       Person.validates_confirmation_of :title, validation_options
-      @person.title_confirmation = 'foo'
-      call = [:title_confirmation, :confirmation, generate_message_options.merge(attribute: 'Title')]
+      @person.title_confirmation = "foo"
+      call = [:title_confirmation, :confirmation, generate_message_options.merge(attribute: "Title")]
       assert_called_with(@person.errors, :generate_message, call) do
         @person.valid?
       end
@@ -99,7 +100,7 @@ class I18nValidationTest < ActiveModel::TestCase
   COMMON_CASES.each do |name, validation_options, generate_message_options|
     test "validates_length_of for :too_long generated message #{name}" do
       Person.validates_length_of :title, validation_options.merge(within: 3..5)
-      @person.title = 'this title is too long'
+      @person.title = "this title is too long"
       call = [:title, :too_long, generate_message_options.merge(count: 5)]
       assert_called_with(@person.errors, :generate_message, call) do
         @person.valid?
@@ -120,8 +121,8 @@ class I18nValidationTest < ActiveModel::TestCase
   COMMON_CASES.each do |name, validation_options, generate_message_options|
     test "validates_format_of on generated message #{name}" do
       Person.validates_format_of :title, validation_options.merge(with: /\A[1-9][0-9]*\z/)
-      @person.title = '72x'
-      call = [:title, :invalid, generate_message_options.merge(value: '72x')]
+      @person.title = "72x"
+      call = [:title, :invalid, generate_message_options.merge(value: "72x")]
       assert_called_with(@person.errors, :generate_message, call) do
         @person.valid?
       end
@@ -131,8 +132,8 @@ class I18nValidationTest < ActiveModel::TestCase
   COMMON_CASES.each do |name, validation_options, generate_message_options|
     test "validates_inclusion_of on generated message #{name}" do
       Person.validates_inclusion_of :title, validation_options.merge(in: %w(a b c))
-      @person.title = 'z'
-      call = [:title, :inclusion, generate_message_options.merge(value: 'z')]
+      @person.title = "z"
+      call = [:title, :inclusion, generate_message_options.merge(value: "z")]
       assert_called_with(@person.errors, :generate_message, call) do
         @person.valid?
       end
@@ -142,8 +143,8 @@ class I18nValidationTest < ActiveModel::TestCase
   COMMON_CASES.each do |name, validation_options, generate_message_options|
     test "validates_inclusion_of using :within on generated message #{name}" do
       Person.validates_inclusion_of :title, validation_options.merge(within: %w(a b c))
-      @person.title = 'z'
-      call = [:title, :inclusion, generate_message_options.merge(value: 'z')]
+      @person.title = "z"
+      call = [:title, :inclusion, generate_message_options.merge(value: "z")]
       assert_called_with(@person.errors, :generate_message, call) do
         @person.valid?
       end
@@ -153,8 +154,8 @@ class I18nValidationTest < ActiveModel::TestCase
   COMMON_CASES.each do |name, validation_options, generate_message_options|
     test "validates_exclusion_of generated message #{name}" do
       Person.validates_exclusion_of :title, validation_options.merge(in: %w(a b c))
-      @person.title = 'a'
-      call = [:title, :exclusion, generate_message_options.merge(value: 'a')]
+      @person.title = "a"
+      call = [:title, :exclusion, generate_message_options.merge(value: "a")]
       assert_called_with(@person.errors, :generate_message, call) do
         @person.valid?
       end
@@ -164,8 +165,8 @@ class I18nValidationTest < ActiveModel::TestCase
   COMMON_CASES.each do |name, validation_options, generate_message_options|
     test "validates_exclusion_of using :within generated message #{name}" do
       Person.validates_exclusion_of :title, validation_options.merge(within: %w(a b c))
-      @person.title = 'a'
-      call = [:title, :exclusion, generate_message_options.merge(value: 'a')]
+      @person.title = "a"
+      call = [:title, :exclusion, generate_message_options.merge(value: "a")]
       assert_called_with(@person.errors, :generate_message, call) do
         @person.valid?
       end
@@ -175,8 +176,8 @@ class I18nValidationTest < ActiveModel::TestCase
   COMMON_CASES.each do |name, validation_options, generate_message_options|
     test "validates_numericality_of generated message #{name}" do
       Person.validates_numericality_of :title, validation_options
-      @person.title = 'a'
-      call = [:title, :not_a_number, generate_message_options.merge(value: 'a')]
+      @person.title = "a"
+      call = [:title, :not_a_number, generate_message_options.merge(value: "a")]
       assert_called_with(@person.errors, :generate_message, call) do
         @person.valid?
       end
@@ -186,8 +187,8 @@ class I18nValidationTest < ActiveModel::TestCase
   COMMON_CASES.each do |name, validation_options, generate_message_options|
     test "validates_numericality_of for :only_integer on generated message #{name}" do
       Person.validates_numericality_of :title, validation_options.merge(only_integer: true)
-      @person.title = '0.0'
-      call = [:title, :not_an_integer, generate_message_options.merge(value: '0.0')]
+      @person.title = "0.0"
+      call = [:title, :not_an_integer, generate_message_options.merge(value: "0.0")]
       assert_called_with(@person.errors, :generate_message, call) do
         @person.valid?
       end
@@ -225,35 +226,35 @@ class I18nValidationTest < ActiveModel::TestCase
     end
 
     test "#{validation} finds custom model key translation when #{error_type}" do
-      I18n.backend.store_translations 'en', activemodel: { errors: { models: { person: { attributes: { attribute => { error_type => 'custom message' } } } } } }
-      I18n.backend.store_translations 'en', errors: { messages: { error_type => 'global message'}}
+      I18n.backend.store_translations "en", activemodel: { errors: { models: { person: { attributes: { attribute => { error_type => "custom message" } } } } } }
+      I18n.backend.store_translations "en", errors: { messages: { error_type => "global message" } }
 
       yield(@person, {})
       @person.valid?
-      assert_equal ['custom message'], @person.errors[attribute]
+      assert_equal ["custom message"], @person.errors[attribute]
     end
 
     test "#{validation} finds custom model key translation with interpolation when #{error_type}" do
-      I18n.backend.store_translations 'en', activemodel: { errors: { models: { person: { attributes: { attribute => { error_type => 'custom message with %{extra}' } } } } } }
-      I18n.backend.store_translations 'en', errors: { messages: {error_type => 'global message'} }
+      I18n.backend.store_translations "en", activemodel: { errors: { models: { person: { attributes: { attribute => { error_type => "custom message with %{extra}" } } } } } }
+      I18n.backend.store_translations "en", errors: { messages: { error_type => "global message" } }
 
       yield(@person, { extra: "extra information" })
       @person.valid?
-      assert_equal ['custom message with extra information'], @person.errors[attribute]
+      assert_equal ["custom message with extra information"], @person.errors[attribute]
     end
 
     test "#{validation} finds global default key translation when #{error_type}" do
-      I18n.backend.store_translations 'en', errors: { messages: {error_type => 'global message'} }
+      I18n.backend.store_translations "en", errors: { messages: { error_type => "global message" } }
 
       yield(@person, {})
       @person.valid?
-      assert_equal ['global message'], @person.errors[attribute]
+      assert_equal ["global message"], @person.errors[attribute]
     end
   end
 
   set_expectations_for_validation "validates_confirmation_of", :confirmation do |person, options_to_merge|
     Person.validates_confirmation_of :title, options_to_merge
-    person.title_confirmation = 'foo'
+    person.title_confirmation = "foo"
   end
 
   set_expectations_for_validation "validates_acceptance_of", :accepted do |person, options_to_merge|
@@ -287,17 +288,17 @@ class I18nValidationTest < ActiveModel::TestCase
 
   set_expectations_for_validation "validates_exclusion_of", :exclusion do |person, options_to_merge|
     Person.validates_exclusion_of :title, options_to_merge.merge(in: %w(a b c))
-    person.title = 'a'
+    person.title = "a"
   end
 
   set_expectations_for_validation "validates_numericality_of", :not_a_number do |person, options_to_merge|
     Person.validates_numericality_of :title, options_to_merge
-    person.title = 'a'
+    person.title = "a"
   end
 
   set_expectations_for_validation "validates_numericality_of", :not_an_integer do |person, options_to_merge|
     Person.validates_numericality_of :title, options_to_merge.merge(only_integer: true)
-    person.title = '1.0'
+    person.title = "1.0"
   end
 
   set_expectations_for_validation "validates_numericality_of", :odd do |person, options_to_merge|
@@ -311,7 +312,7 @@ class I18nValidationTest < ActiveModel::TestCase
   end
 
   def test_validations_with_message_symbol_must_translate
-    I18n.backend.store_translations 'en', errors: { messages: { custom_error: "I am a custom error" } }
+    I18n.backend.store_translations "en", errors: { messages: { custom_error: "I am a custom error" } }
     Person.validates_presence_of :title, message: :custom_error
     @person.title = nil
     @person.valid?
@@ -319,7 +320,7 @@ class I18nValidationTest < ActiveModel::TestCase
   end
 
   def test_validates_with_message_symbol_must_translate_per_attribute
-    I18n.backend.store_translations 'en', activemodel: { errors: { models: { person: { attributes: { title: { custom_error: "I am a custom error" } } } } } }
+    I18n.backend.store_translations "en", activemodel: { errors: { models: { person: { attributes: { title: { custom_error: "I am a custom error" } } } } } }
     Person.validates_presence_of :title, message: :custom_error
     @person.title = nil
     @person.valid?
@@ -327,7 +328,7 @@ class I18nValidationTest < ActiveModel::TestCase
   end
 
   def test_validates_with_message_symbol_must_translate_per_model
-    I18n.backend.store_translations 'en', activemodel: { errors: { models: { person: { custom_error: "I am a custom error" } } } }
+    I18n.backend.store_translations "en", activemodel: { errors: { models: { person: { custom_error: "I am a custom error" } } } }
     Person.validates_presence_of :title, message: :custom_error
     @person.title = nil
     @person.valid?
diff --git a/activemodel/test/cases/validations/inclusion_validation_test.rb b/activemodel/test/cases/validations/inclusion_validation_test.rb
index 9bd44175a6..94df0649a9 100644
--- a/activemodel/test/cases/validations/inclusion_validation_test.rb
+++ b/activemodel/test/cases/validations/inclusion_validation_test.rb
@@ -1,17 +1,18 @@
-require 'cases/helper'
-require 'active_support/all'
+# frozen_string_literal: true
 
-require 'models/topic'
-require 'models/person'
+require "cases/helper"
+require "active_support/all"
 
-class InclusionValidationTest < ActiveModel::TestCase
+require "models/topic"
+require "models/person"
 
+class InclusionValidationTest < ActiveModel::TestCase
   def teardown
     Topic.clear_validators!
   end
 
   def test_validates_inclusion_of_range
-    Topic.validates_inclusion_of(:title, in: 'aaa'..'bbb')
+    Topic.validates_inclusion_of(:title, in: "aaa".."bbb")
     assert Topic.new("title" => "bbc", "content" => "abc").invalid?
     assert Topic.new("title" => "aa", "content" => "abc").invalid?
     assert Topic.new("title" => "aaab", "content" => "abc").invalid?
@@ -24,35 +25,35 @@ class InclusionValidationTest < ActiveModel::TestCase
     range_begin = 1.year.ago
     range_end = Time.now
     Topic.validates_inclusion_of(:created_at, in: range_begin..range_end)
-    assert Topic.new(title: 'aaa', created_at: 2.years.ago).invalid?
-    assert Topic.new(title: 'aaa', created_at: 3.months.ago).valid?
-    assert Topic.new(title: 'aaa', created_at: 37.weeks.from_now).invalid?
-    assert Topic.new(title: 'aaa', created_at: range_begin).valid?
-    assert Topic.new(title: 'aaa', created_at: range_end).valid?
+    assert Topic.new(title: "aaa", created_at: 2.years.ago).invalid?
+    assert Topic.new(title: "aaa", created_at: 3.months.ago).valid?
+    assert Topic.new(title: "aaa", created_at: 37.weeks.from_now).invalid?
+    assert Topic.new(title: "aaa", created_at: range_begin).valid?
+    assert Topic.new(title: "aaa", created_at: range_end).valid?
   end
 
   def test_validates_inclusion_of_date_range
     range_begin = 1.year.until(Date.today)
     range_end = Date.today
     Topic.validates_inclusion_of(:created_at, in: range_begin..range_end)
-    assert Topic.new(title: 'aaa', created_at: 2.years.until(Date.today)).invalid?
-    assert Topic.new(title: 'aaa', created_at: 3.months.until(Date.today)).valid?
-    assert Topic.new(title: 'aaa', created_at: 37.weeks.since(Date.today)).invalid?
-    assert Topic.new(title: 'aaa', created_at: 1.year.until(Date.today)).valid?
-    assert Topic.new(title: 'aaa', created_at: Date.today).valid?
-    assert Topic.new(title: 'aaa', created_at: range_begin).valid?
-    assert Topic.new(title: 'aaa', created_at: range_end).valid?
+    assert Topic.new(title: "aaa", created_at: 2.years.until(Date.today)).invalid?
+    assert Topic.new(title: "aaa", created_at: 3.months.until(Date.today)).valid?
+    assert Topic.new(title: "aaa", created_at: 37.weeks.since(Date.today)).invalid?
+    assert Topic.new(title: "aaa", created_at: 1.year.until(Date.today)).valid?
+    assert Topic.new(title: "aaa", created_at: Date.today).valid?
+    assert Topic.new(title: "aaa", created_at: range_begin).valid?
+    assert Topic.new(title: "aaa", created_at: range_end).valid?
   end
 
   def test_validates_inclusion_of_date_time_range
     range_begin = 1.year.until(DateTime.current)
     range_end = DateTime.current
     Topic.validates_inclusion_of(:created_at, in: range_begin..range_end)
-    assert Topic.new(title: 'aaa', created_at: 2.years.until(DateTime.current)).invalid?
-    assert Topic.new(title: 'aaa', created_at: 3.months.until(DateTime.current)).valid?
-    assert Topic.new(title: 'aaa', created_at: 37.weeks.since(DateTime.current)).invalid?
-    assert Topic.new(title: 'aaa', created_at: range_begin).valid?
-    assert Topic.new(title: 'aaa', created_at: range_end).valid?
+    assert Topic.new(title: "aaa", created_at: 2.years.until(DateTime.current)).invalid?
+    assert Topic.new(title: "aaa", created_at: 3.months.until(DateTime.current)).valid?
+    assert Topic.new(title: "aaa", created_at: 37.weeks.since(DateTime.current)).invalid?
+    assert Topic.new(title: "aaa", created_at: range_begin).valid?
+    assert Topic.new(title: "aaa", created_at: range_end).valid?
   end
 
   def test_validates_inclusion_of
@@ -122,7 +123,7 @@ class InclusionValidationTest < ActiveModel::TestCase
   end
 
   def test_validates_inclusion_of_with_lambda
-    Topic.validates_inclusion_of :title, in: lambda{ |topic| topic.author_name == "sikachu" ? %w( monkey elephant ) : %w( abe wasabi ) }
+    Topic.validates_inclusion_of :title, in: lambda { |topic| topic.author_name == "sikachu" ? %w( monkey elephant ) : %w( abe wasabi ) }
 
     t = Topic.new
     t.title = "wasabi"
diff --git a/activemodel/test/cases/validations/length_validation_test.rb b/activemodel/test/cases/validations/length_validation_test.rb
index 11dce1df20..42f76f3e3c 100644
--- a/activemodel/test/cases/validations/length_validation_test.rb
+++ b/activemodel/test/cases/validations/length_validation_test.rb
@@ -1,7 +1,9 @@
-require 'cases/helper'
+# frozen_string_literal: true
 
-require 'models/topic'
-require 'models/person'
+require "cases/helper"
+
+require "models/topic"
+require "models/person"
 
 class LengthValidationTest < ActiveModel::TestCase
   def teardown
@@ -9,7 +11,7 @@ class LengthValidationTest < ActiveModel::TestCase
   end
 
   def test_validates_length_of_with_allow_nil
-    Topic.validates_length_of( :title, is: 5, allow_nil: true )
+    Topic.validates_length_of(:title, is: 5, allow_nil: true)
 
     assert Topic.new("title" => "ab").invalid?
     assert Topic.new("title" => "").invalid?
@@ -18,7 +20,7 @@ class LengthValidationTest < ActiveModel::TestCase
   end
 
   def test_validates_length_of_with_allow_blank
-    Topic.validates_length_of( :title, is: 5, allow_blank: true )
+    Topic.validates_length_of(:title, is: 5, allow_blank: true)
 
     assert Topic.new("title" => "ab").invalid?
     assert Topic.new("title" => "").valid?
@@ -104,7 +106,7 @@ class LengthValidationTest < ActiveModel::TestCase
     assert_equal ["is too short (minimum is 3 characters)"], t.errors[:content]
 
     t.title = "abe"
-    t.content  = "mad"
+    t.content = "mad"
     assert t.valid?
   end
 
@@ -125,7 +127,7 @@ class LengthValidationTest < ActiveModel::TestCase
   def test_optionally_validates_length_of_using_within
     Topic.validates_length_of :title, :content, within: 3..5, allow_nil: true
 
-    t = Topic.new('title' => 'abc', 'content' => 'abcd')
+    t = Topic.new("title" => "abc", "content" => "abcd")
     assert t.valid?
 
     t.title = nil
@@ -161,8 +163,8 @@ class LengthValidationTest < ActiveModel::TestCase
   end
 
   def test_validates_length_of_using_bignum
-    bigmin = 2 ** 30
-    bigmax = 2 ** 32
+    bigmin = 2**30
+    bigmax = 2**32
     bigrange = bigmin...bigmax
     assert_nothing_raised do
       Topic.validates_length_of :title, is: bigmin + 5
@@ -183,7 +185,7 @@ class LengthValidationTest < ActiveModel::TestCase
   end
 
   def test_validates_length_of_custom_errors_for_minimum_with_message
-    Topic.validates_length_of( :title, minimum: 5, message: "boo %{count}" )
+    Topic.validates_length_of(:title, minimum: 5, message: "boo %{count}")
     t = Topic.new("title" => "uhoh", "content" => "whatever")
     assert t.invalid?
     assert t.errors[:title].any?
@@ -191,7 +193,7 @@ class LengthValidationTest < ActiveModel::TestCase
   end
 
   def test_validates_length_of_custom_errors_for_minimum_with_too_short
-    Topic.validates_length_of( :title, minimum: 5, too_short: "hoo %{count}" )
+    Topic.validates_length_of(:title, minimum: 5, too_short: "hoo %{count}")
     t = Topic.new("title" => "uhoh", "content" => "whatever")
     assert t.invalid?
     assert t.errors[:title].any?
@@ -199,7 +201,7 @@ class LengthValidationTest < ActiveModel::TestCase
   end
 
   def test_validates_length_of_custom_errors_for_maximum_with_message
-    Topic.validates_length_of( :title, maximum: 5, message: "boo %{count}" )
+    Topic.validates_length_of(:title, maximum: 5, message: "boo %{count}")
     t = Topic.new("title" => "uhohuhoh", "content" => "whatever")
     assert t.invalid?
     assert t.errors[:title].any?
@@ -220,7 +222,7 @@ class LengthValidationTest < ActiveModel::TestCase
   end
 
   def test_validates_length_of_custom_errors_for_maximum_with_too_long
-    Topic.validates_length_of( :title, maximum: 5, too_long: "hoo %{count}" )
+    Topic.validates_length_of(:title, maximum: 5, too_long: "hoo %{count}")
     t = Topic.new("title" => "uhohuhoh", "content" => "whatever")
     assert t.invalid?
     assert t.errors[:title].any?
@@ -228,21 +230,21 @@ class LengthValidationTest < ActiveModel::TestCase
   end
 
   def test_validates_length_of_custom_errors_for_both_too_short_and_too_long
-    Topic.validates_length_of :title, minimum: 3, maximum: 5, too_short: 'too short', too_long: 'too long'
+    Topic.validates_length_of :title, minimum: 3, maximum: 5, too_short: "too short", too_long: "too long"
 
-    t = Topic.new(title: 'a')
+    t = Topic.new(title: "a")
     assert t.invalid?
     assert t.errors[:title].any?
-    assert_equal ['too short'], t.errors['title']
+    assert_equal ["too short"], t.errors["title"]
 
-    t = Topic.new(title: 'aaaaaa')
+    t = Topic.new(title: "aaaaaa")
     assert t.invalid?
     assert t.errors[:title].any?
-    assert_equal ['too long'], t.errors['title']
+    assert_equal ["too long"], t.errors["title"]
   end
 
   def test_validates_length_of_custom_errors_for_is_with_message
-    Topic.validates_length_of( :title, is: 5, message: "boo %{count}" )
+    Topic.validates_length_of(:title, is: 5, message: "boo %{count}")
     t = Topic.new("title" => "uhohuhoh", "content" => "whatever")
     assert t.invalid?
     assert t.errors[:title].any?
@@ -250,7 +252,7 @@ class LengthValidationTest < ActiveModel::TestCase
   end
 
   def test_validates_length_of_custom_errors_for_is_with_wrong_length
-    Topic.validates_length_of( :title, is: 5, wrong_length: "hoo %{count}" )
+    Topic.validates_length_of(:title, is: 5, wrong_length: "hoo %{count}")
     t = Topic.new("title" => "uhohuhoh", "content" => "whatever")
     assert t.invalid?
     assert t.errors[:title].any?
@@ -289,7 +291,7 @@ class LengthValidationTest < ActiveModel::TestCase
     assert_equal ["is too short (minimum is 3 characters)"], t.errors[:title]
     assert_equal ["is too long (maximum is 5 characters)"], t.errors[:content]
     t.title = "一二三"
-    t.content  = "12三"
+    t.content = "12三"
     assert t.valid?
   end
 
@@ -318,43 +320,6 @@ class LengthValidationTest < ActiveModel::TestCase
     assert_equal ["is the wrong length (should be 5 characters)"], t.errors["title"]
   end
 
-  def test_validates_length_of_with_block
-    assert_deprecated do
-      Topic.validates_length_of(
-        :content,
-        minimum: 5,
-        too_short: "Your essay must be at least %{count} words.",
-        tokenizer: lambda {|str| str.scan(/\w+/) },
-      )
-    end
-    t = Topic.new(content: "this content should be long enough")
-    assert t.valid?
-
-    t.content = "not long enough"
-    assert t.invalid?
-    assert t.errors[:content].any?
-    assert_equal ["Your essay must be at least 5 words."], t.errors[:content]
-  end
-
-
-  def test_validates_length_of_with_symbol
-    assert_deprecated do
-      Topic.validates_length_of(
-        :content,
-        minimum: 5,
-        too_short: "Your essay must be at least %{count} words.",
-        tokenizer: :my_word_tokenizer,
-      )
-    end
-    t = Topic.new(content: "this content should be long enough")
-    assert t.valid?
-
-    t.content = "not long enough"
-    assert t.invalid?
-    assert t.errors[:content].any?
-    assert_equal ["Your essay must be at least 5 words."], t.errors[:content]
-  end
-
   def test_validates_length_of_for_integer
     Topic.validates_length_of(:approved, is: 4)
 
@@ -440,9 +405,40 @@ class LengthValidationTest < ActiveModel::TestCase
 
   def test_validates_with_diff_in_option
     Topic.validates_length_of(:title, is: 5)
-    Topic.validates_length_of(:title, is: 5, if: Proc.new { false } )
+    Topic.validates_length_of(:title, is: 5, if: Proc.new { false })
 
     assert Topic.new("title" => "david").valid?
     assert Topic.new("title" => "david2").invalid?
   end
+
+  def test_validates_length_of_using_proc_as_maximum
+    Topic.validates_length_of :title, maximum: ->(model) { 5 }
+
+    t = Topic.new("title" => "valid", "content" => "whatever")
+    assert t.valid?
+
+    t.title = "notvalid"
+    assert t.invalid?
+    assert t.errors[:title].any?
+    assert_equal ["is too long (maximum is 5 characters)"], t.errors[:title]
+
+    t.title = ""
+    assert t.valid?
+  end
+
+  def test_validates_length_of_using_proc_as_maximum_with_model_method
+    Topic.send(:define_method, :max_title_length, lambda { 5 })
+    Topic.validates_length_of :title, maximum: Proc.new(&:max_title_length)
+
+    t = Topic.new("title" => "valid", "content" => "whatever")
+    assert t.valid?
+
+    t.title = "notvalid"
+    assert t.invalid?
+    assert t.errors[:title].any?
+    assert_equal ["is too long (maximum is 5 characters)"], t.errors[:title]
+
+    t.title = ""
+    assert t.valid?
+  end
 end
diff --git a/activemodel/test/cases/validations/numericality_validation_test.rb b/activemodel/test/cases/validations/numericality_validation_test.rb
index 74a048537d..5413255e6b 100644
--- a/activemodel/test/cases/validations/numericality_validation_test.rb
+++ b/activemodel/test/cases/validations/numericality_validation_test.rb
@@ -1,13 +1,14 @@
-require 'cases/helper'
+# frozen_string_literal: true
 
-require 'models/topic'
-require 'models/person'
+require "cases/helper"
 
-require 'bigdecimal'
-require 'active_support/core_ext/big_decimal'
+require "models/topic"
+require "models/person"
 
-class NumericalityValidationTest < ActiveModel::TestCase
+require "bigdecimal"
+require "active_support/core_ext/big_decimal"
 
+class NumericalityValidationTest < ActiveModel::TestCase
   def teardown
     Topic.clear_validators!
   end
@@ -19,9 +20,9 @@ class NumericalityValidationTest < ActiveModel::TestCase
   INTEGER_STRINGS = %w(0 +0 -0 10 +10 -10 0090 -090)
   FLOATS = [0.0, 10.0, 10.5, -10.5, -0.0001] + FLOAT_STRINGS
   INTEGERS = [0, 10, -10] + INTEGER_STRINGS
-  BIGDECIMAL = BIGDECIMAL_STRINGS.collect! { |bd| BigDecimal.new(bd) }
+  BIGDECIMAL = BIGDECIMAL_STRINGS.collect! { |bd| BigDecimal(bd) }
   JUNK = ["not a number", "42 not a number", "0xdeadbeef", "0xinvalidhex", "0Xdeadbeef", "00-1", "--3", "+-3", "+3-1", "-+019.0", "12.12.13.12", "123\nnot a number"]
-  INFINITY = [1.0/0.0]
+  INFINITY = [1.0 / 0.0]
 
   def test_default_validates_numericality_of
     Topic.validates_numericality_of :approved
@@ -36,6 +37,13 @@ class NumericalityValidationTest < ActiveModel::TestCase
     valid!(NIL + FLOATS + INTEGERS + BIGDECIMAL + INFINITY)
   end
 
+  def test_validates_numericality_of_with_blank_allowed
+    Topic.validates_numericality_of :approved, allow_blank: true
+
+    invalid!(JUNK)
+    valid!(NIL + BLANK + FLOATS + INTEGERS + BIGDECIMAL + INFINITY)
+  end
+
   def test_validates_numericality_of_with_integer_only
     Topic.validates_numericality_of :approved, only_integer: true
 
@@ -51,7 +59,7 @@ class NumericalityValidationTest < ActiveModel::TestCase
   end
 
   def test_validates_numericality_of_with_integer_only_and_symbol_as_value
-    Topic.validates_numericality_of :approved, only_integer: :condition_is_true_but_its_not
+    Topic.validates_numericality_of :approved, only_integer: :condition_is_false
 
     invalid!(NIL + BLANK + JUNK)
     valid!(FLOATS + INTEGERS + BIGDECIMAL + INFINITY)
@@ -68,119 +76,119 @@ class NumericalityValidationTest < ActiveModel::TestCase
   def test_validates_numericality_with_greater_than
     Topic.validates_numericality_of :approved, greater_than: 10
 
-    invalid!([-10, 10], 'must be greater than 10')
+    invalid!([-10, 10], "must be greater than 10")
     valid!([11])
   end
 
   def test_validates_numericality_with_greater_than_using_differing_numeric_types
-    Topic.validates_numericality_of :approved, greater_than: BigDecimal.new('97.18')
+    Topic.validates_numericality_of :approved, greater_than: BigDecimal("97.18")
 
-    invalid!([-97.18, BigDecimal.new('97.18'), BigDecimal('-97.18')], 'must be greater than 97.18')
-    valid!([97.18, 98, BigDecimal.new('98')]) # Notice the 97.18 as a float is greater than 97.18 as a BigDecimal due to floating point precision
+    invalid!([-97.18, BigDecimal("97.18"), BigDecimal("-97.18")], "must be greater than 97.18")
+    valid!([97.19, 98, BigDecimal("98"), BigDecimal("97.19")])
   end
 
   def test_validates_numericality_with_greater_than_using_string_value
     Topic.validates_numericality_of :approved, greater_than: 10
 
-    invalid!(['-10', '9', '9.9', '10'], 'must be greater than 10')
-    valid!(['10.1', '11'])
+    invalid!(["-10", "9", "9.9", "10"], "must be greater than 10")
+    valid!(["10.1", "11"])
   end
 
   def test_validates_numericality_with_greater_than_or_equal
     Topic.validates_numericality_of :approved, greater_than_or_equal_to: 10
 
-    invalid!([-9, 9], 'must be greater than or equal to 10')
+    invalid!([-9, 9], "must be greater than or equal to 10")
     valid!([10])
   end
 
   def test_validates_numericality_with_greater_than_or_equal_using_differing_numeric_types
-    Topic.validates_numericality_of :approved, greater_than_or_equal_to: BigDecimal.new('97.18') 
+    Topic.validates_numericality_of :approved, greater_than_or_equal_to: BigDecimal("97.18")
 
-    invalid!([-97.18, 97.17, 97, BigDecimal.new('97.17'), BigDecimal.new('-97.18')], 'must be greater than or equal to 97.18')
-    valid!([97.18, 98, BigDecimal.new('97.19')])
+    invalid!([-97.18, 97.17, 97, BigDecimal("97.17"), BigDecimal("-97.18")], "must be greater than or equal to 97.18")
+    valid!([97.18, 98, BigDecimal("97.19")])
   end
 
   def test_validates_numericality_with_greater_than_or_equal_using_string_value
     Topic.validates_numericality_of :approved, greater_than_or_equal_to: 10
 
-    invalid!(['-10', '9', '9.9'], 'must be greater than or equal to 10')
-    valid!(['10', '10.1', '11'])
+    invalid!(["-10", "9", "9.9"], "must be greater than or equal to 10")
+    valid!(["10", "10.1", "11"])
   end
 
   def test_validates_numericality_with_equal_to
     Topic.validates_numericality_of :approved, equal_to: 10
 
-    invalid!([-10, 11] + INFINITY, 'must be equal to 10')
+    invalid!([-10, 11] + INFINITY, "must be equal to 10")
     valid!([10])
   end
 
   def test_validates_numericality_with_equal_to_using_differing_numeric_types
-    Topic.validates_numericality_of :approved, equal_to: BigDecimal.new('97.18')
+    Topic.validates_numericality_of :approved, equal_to: BigDecimal("97.18")
 
-    invalid!([-97.18, 97.18], 'must be equal to 97.18')
-    valid!([BigDecimal.new('97.18')])
+    invalid!([-97.18], "must be equal to 97.18")
+    valid!([BigDecimal("97.18")])
   end
 
   def test_validates_numericality_with_equal_to_using_string_value
     Topic.validates_numericality_of :approved, equal_to: 10
 
-    invalid!(['-10', '9', '9.9', '10.1', '11'], 'must be equal to 10')
-    valid!(['10'])
+    invalid!(["-10", "9", "9.9", "10.1", "11"], "must be equal to 10")
+    valid!(["10"])
   end
 
   def test_validates_numericality_with_less_than
     Topic.validates_numericality_of :approved, less_than: 10
 
-    invalid!([10], 'must be less than 10')
+    invalid!([10], "must be less than 10")
     valid!([-9, 9])
   end
 
   def test_validates_numericality_with_less_than_using_differing_numeric_types
-    Topic.validates_numericality_of :approved, less_than: BigDecimal.new('97.18')
+    Topic.validates_numericality_of :approved, less_than: BigDecimal("97.18")
 
-    invalid!([97.18, BigDecimal.new('97.18')], 'must be less than 97.18')
-    valid!([-97.0, 97.0, -97, 97, BigDecimal.new('-97'), BigDecimal.new('97')])
+    invalid!([97.18, BigDecimal("97.18")], "must be less than 97.18")
+    valid!([-97.0, 97.0, -97, 97, BigDecimal("-97"), BigDecimal("97")])
   end
 
   def test_validates_numericality_with_less_than_using_string_value
     Topic.validates_numericality_of :approved, less_than: 10
 
-    invalid!(['10', '10.1', '11'], 'must be less than 10')
-    valid!(['-10', '9', '9.9'])
+    invalid!(["10", "10.1", "11"], "must be less than 10")
+    valid!(["-10", "9", "9.9"])
   end
 
   def test_validates_numericality_with_less_than_or_equal_to
     Topic.validates_numericality_of :approved, less_than_or_equal_to: 10
 
-    invalid!([11], 'must be less than or equal to 10')
+    invalid!([11], "must be less than or equal to 10")
     valid!([-10, 10])
   end
 
   def test_validates_numericality_with_less_than_or_equal_to_using_differing_numeric_types
-    Topic.validates_numericality_of :approved, less_than_or_equal_to: BigDecimal.new('97.18')
+    Topic.validates_numericality_of :approved, less_than_or_equal_to: BigDecimal("97.18")
 
-    invalid!([97.18, 98], 'must be less than or equal to 97.18')
-    valid!([-97.18, BigDecimal.new('-97.18'), BigDecimal.new('97.18')])
+    invalid!([97.19, 98], "must be less than or equal to 97.18")
+    valid!([-97.18, BigDecimal("-97.18"), BigDecimal("97.18")])
   end
 
   def test_validates_numericality_with_less_than_or_equal_using_string_value
     Topic.validates_numericality_of :approved, less_than_or_equal_to: 10
 
-    invalid!(['10.1', '11'], 'must be less than or equal to 10')
-    valid!(['-10', '9', '9.9', '10'])
+    invalid!(["10.1", "11"], "must be less than or equal to 10")
+    valid!(["-10", "9", "9.9", "10"])
   end
 
   def test_validates_numericality_with_odd
     Topic.validates_numericality_of :approved, odd: true
 
-    invalid!([-2, 2], 'must be odd')
+    invalid!([-2, 2], "must be odd")
     valid!([-1, 1])
   end
 
   def test_validates_numericality_with_even
     Topic.validates_numericality_of :approved, even: true
 
-    invalid!([-1, 1], 'must be even')
+    invalid!([-1, 1], "must be even")
     valid!([-2, 2])
   end
 
@@ -201,8 +209,8 @@ class NumericalityValidationTest < ActiveModel::TestCase
   def test_validates_numericality_with_other_than_using_string_value
     Topic.validates_numericality_of :approved, other_than: 0
 
-    invalid!(['0', '0.0'])
-    valid!(['-1', '1.1', '42'])
+    invalid!(["0", "0.0"])
+    valid!(["-1", "1.1", "42"])
   end
 
   def test_validates_numericality_with_proc
@@ -254,35 +262,44 @@ class NumericalityValidationTest < ActiveModel::TestCase
     Person.clear_validators!
   end
 
+  def test_validates_numericality_with_exponent_number
+    base = 10_000_000_000_000_000
+    Topic.validates_numericality_of :approved, less_than_or_equal_to: base
+    topic = Topic.new
+    topic.approved = (base + 1).to_s
+
+    assert topic.invalid?
+  end
+
   def test_validates_numericality_with_invalid_args
-    assert_raise(ArgumentError){ Topic.validates_numericality_of :approved, greater_than_or_equal_to: "foo" }
-    assert_raise(ArgumentError){ Topic.validates_numericality_of :approved, less_than_or_equal_to: "foo" }
-    assert_raise(ArgumentError){ Topic.validates_numericality_of :approved, greater_than: "foo" }
-    assert_raise(ArgumentError){ Topic.validates_numericality_of :approved, less_than: "foo" }
-    assert_raise(ArgumentError){ Topic.validates_numericality_of :approved, equal_to: "foo" }
+    assert_raise(ArgumentError) { Topic.validates_numericality_of :approved, greater_than_or_equal_to: "foo" }
+    assert_raise(ArgumentError) { Topic.validates_numericality_of :approved, less_than_or_equal_to: "foo" }
+    assert_raise(ArgumentError) { Topic.validates_numericality_of :approved, greater_than: "foo" }
+    assert_raise(ArgumentError) { Topic.validates_numericality_of :approved, less_than: "foo" }
+    assert_raise(ArgumentError) { Topic.validates_numericality_of :approved, equal_to: "foo" }
   end
 
   private
 
-  def invalid!(values, error = nil)
-    with_each_topic_approved_value(values) do |topic, value|
-      assert topic.invalid?, "#{value.inspect} not rejected as a number"
-      assert topic.errors[:approved].any?, "FAILED for #{value.inspect}"
-      assert_equal error, topic.errors[:approved].first if error
+    def invalid!(values, error = nil)
+      with_each_topic_approved_value(values) do |topic, value|
+        assert topic.invalid?, "#{value.inspect} not rejected as a number"
+        assert topic.errors[:approved].any?, "FAILED for #{value.inspect}"
+        assert_equal error, topic.errors[:approved].first if error
+      end
     end
-  end
 
-  def valid!(values)
-    with_each_topic_approved_value(values) do |topic, value|
-      assert topic.valid?, "#{value.inspect} not accepted as a number with validation error: #{topic.errors[:approved].first}"
+    def valid!(values)
+      with_each_topic_approved_value(values) do |topic, value|
+        assert topic.valid?, "#{value.inspect} not accepted as a number with validation error: #{topic.errors[:approved].first}"
+      end
     end
-  end
 
-  def with_each_topic_approved_value(values)
-    topic = Topic.new(title: "numeric test", content: "whatever")
-    values.each do |value|
-      topic.approved = value
-      yield topic, value
+    def with_each_topic_approved_value(values)
+      topic = Topic.new(title: "numeric test", content: "whatever")
+      values.each do |value|
+        topic.approved = value
+        yield topic, value
+      end
     end
-  end
 end
diff --git a/activemodel/test/cases/validations/presence_validation_test.rb b/activemodel/test/cases/validations/presence_validation_test.rb
index 59b9db0795..22c2f0af87 100644
--- a/activemodel/test/cases/validations/presence_validation_test.rb
+++ b/activemodel/test/cases/validations/presence_validation_test.rb
@@ -1,11 +1,12 @@
-require 'cases/helper'
+# frozen_string_literal: true
 
-require 'models/topic'
-require 'models/person'
-require 'models/custom_reader'
+require "cases/helper"
 
-class PresenceValidationTest < ActiveModel::TestCase
+require "models/topic"
+require "models/person"
+require "models/custom_reader"
 
+class PresenceValidationTest < ActiveModel::TestCase
   teardown do
     Topic.clear_validators!
     Person.clear_validators!
@@ -21,7 +22,7 @@ class PresenceValidationTest < ActiveModel::TestCase
     assert_equal ["can't be blank"], t.errors[:content]
 
     t.title = "something"
-    t.content  = "   "
+    t.content = "   "
 
     assert t.invalid?
     assert_equal ["can't be blank"], t.errors[:content]
diff --git a/activemodel/test/cases/validations/validates_test.rb b/activemodel/test/cases/validations/validates_test.rb
index 04101f3545..7f32f5dc74 100644
--- a/activemodel/test/cases/validations/validates_test.rb
+++ b/activemodel/test/cases/validations/validates_test.rb
@@ -1,8 +1,10 @@
-require 'cases/helper'
-require 'models/person'
-require 'models/topic'
-require 'models/person_with_validator'
-require 'validators/namespace/email_validator'
+# frozen_string_literal: true
+
+require "cases/helper"
+require "models/person"
+require "models/topic"
+require "models/person_with_validator"
+require "validators/namespace/email_validator"
 
 class ValidatesTest < ActiveModel::TestCase
   setup :reset_callbacks
@@ -17,21 +19,21 @@ class ValidatesTest < ActiveModel::TestCase
   def test_validates_with_messages_empty
     Person.validates :title, presence: { message: "" }
     person = Person.new
-    assert !person.valid?, 'person should not be valid.'
+    assert !person.valid?, "person should not be valid."
   end
 
   def test_validates_with_built_in_validation
     Person.validates :title, numericality: true
     person = Person.new
     person.valid?
-    assert_equal ['is not a number'], person.errors[:title]
+    assert_equal ["is not a number"], person.errors[:title]
   end
 
   def test_validates_with_attribute_specified_as_string
     Person.validates "title", numericality: true
     person = Person.new
     person.valid?
-    assert_equal ['is not a number'], person.errors[:title]
+    assert_equal ["is not a number"], person.errors[:title]
 
     person = Person.new
     person.title = 123
@@ -39,38 +41,44 @@ class ValidatesTest < ActiveModel::TestCase
   end
 
   def test_validates_with_built_in_validation_and_options
-    Person.validates :salary, numericality: { message: 'my custom message' }
+    Person.validates :salary, numericality: { message: "my custom message" }
     person = Person.new
     person.valid?
-    assert_equal ['my custom message'], person.errors[:salary]
+    assert_equal ["my custom message"], person.errors[:salary]
   end
 
   def test_validates_with_validator_class
     Person.validates :karma, email: true
     person = Person.new
     person.valid?
-    assert_equal ['is not an email'], person.errors[:karma]
+    assert_equal ["is not an email"], person.errors[:karma]
   end
 
   def test_validates_with_namespaced_validator_class
-    Person.validates :karma, :'namespace/email' => true
+    Person.validates :karma, 'namespace/email': true
     person = Person.new
     person.valid?
-    assert_equal ['is not an email'], person.errors[:karma]
+    assert_equal ["is not an email"], person.errors[:karma]
   end
 
   def test_validates_with_if_as_local_conditions
-    Person.validates :karma, presence: true, email: { unless: :condition_is_true }
+    Person.validates :karma, presence: true, email: { if: :condition_is_false }
     person = Person.new
     person.valid?
     assert_equal ["can't be blank"], person.errors[:karma]
   end
 
   def test_validates_with_if_as_shared_conditions
-    Person.validates :karma, presence: true, email: true, if: :condition_is_true
+    Person.validates :karma, presence: true, email: true, if: :condition_is_false
+    person = Person.new
+    assert person.valid?
+  end
+
+  def test_validates_with_unless_as_local_conditions
+    Person.validates :karma, presence: true, email: { unless: :condition_is_true }
     person = Person.new
     person.valid?
-    assert_equal ["can't be blank", "is not an email"], person.errors[:karma].sort
+    assert_equal ["can't be blank"], person.errors[:karma]
   end
 
   def test_validates_with_unless_shared_conditions
@@ -89,7 +97,7 @@ class ValidatesTest < ActiveModel::TestCase
     Person.validates :karma, format: /positive|negative/
     person = Person.new
     assert person.invalid?
-    assert_equal ['is invalid'], person.errors[:karma]
+    assert_equal ["is invalid"], person.errors[:karma]
     person.karma = "positive"
     assert person.valid?
   end
@@ -98,7 +106,7 @@ class ValidatesTest < ActiveModel::TestCase
     Person.validates :gender, inclusion: %w(m f)
     person = Person.new
     assert person.invalid?
-    assert_equal ['is not included in the list'], person.errors[:gender]
+    assert_equal ["is not included in the list"], person.errors[:gender]
     person.gender = "m"
     assert person.valid?
   end
@@ -107,16 +115,16 @@ class ValidatesTest < ActiveModel::TestCase
     Person.validates :karma, length: 6..20
     person = Person.new
     assert person.invalid?
-    assert_equal ['is too short (minimum is 6 characters)'], person.errors[:karma]
-    person.karma = 'something'
+    assert_equal ["is too short (minimum is 6 characters)"], person.errors[:karma]
+    person.karma = "something"
     assert person.valid?
   end
 
   def test_validates_with_validator_class_and_options
-    Person.validates :karma, email: { message: 'my custom message' }
+    Person.validates :karma, email: { message: "my custom message" }
     person = Person.new
     person.valid?
-    assert_equal ['my custom message'], person.errors[:karma]
+    assert_equal ["my custom message"], person.errors[:karma]
   end
 
   def test_validates_with_unknown_validator
@@ -127,14 +135,14 @@ class ValidatesTest < ActiveModel::TestCase
     PersonWithValidator.validates :title, presence: true
     person = PersonWithValidator.new
     person.valid?
-    assert_equal ['Local validator'], person.errors[:title]
+    assert_equal ["Local validator"], person.errors[:title]
   end
 
   def test_validates_with_included_validator_and_options
-    PersonWithValidator.validates :title, presence: { custom: ' please' }
+    PersonWithValidator.validates :title, presence: { custom: " please" }
     person = PersonWithValidator.new
     person.valid?
-    assert_equal ['Local validator please'], person.errors[:title]
+    assert_equal ["Local validator please"], person.errors[:title]
   end
 
   def test_validates_with_included_validator_and_wildcard_shortcut
@@ -143,15 +151,15 @@ class ValidatesTest < ActiveModel::TestCase
     person = PersonWithValidator.new
     person.title = "Ms. Pacman"
     person.valid?
-    assert_equal ['does not appear to be like Mr.'], person.errors[:title]
+    assert_equal ["does not appear to be like Mr."], person.errors[:title]
   end
 
   def test_defining_extra_default_keys_for_validates
-    Topic.validates :title, confirmation: true, message: 'Y U NO CONFIRM'
+    Topic.validates :title, confirmation: true, message: "Y U NO CONFIRM"
     topic = Topic.new
     topic.title = "What's happening"
     topic.title_confirmation = "Not this"
     assert !topic.valid?
-    assert_equal ['Y U NO CONFIRM'], topic.errors[:title_confirmation]
+    assert_equal ["Y U NO CONFIRM"], topic.errors[:title_confirmation]
   end
 end
diff --git a/activemodel/test/cases/validations/validations_context_test.rb b/activemodel/test/cases/validations/validations_context_test.rb
index b901a1523e..024eb1882f 100644
--- a/activemodel/test/cases/validations/validations_context_test.rb
+++ b/activemodel/test/cases/validations/validations_context_test.rb
@@ -1,6 +1,8 @@
-require 'cases/helper'
+# frozen_string_literal: true
 
-require 'models/topic'
+require "cases/helper"
+
+require "models/topic"
 
 class ValidationsContextTest < ActiveModel::TestCase
   def teardown
@@ -38,7 +40,7 @@ class ValidationsContextTest < ActiveModel::TestCase
     Topic.validates_with(ValidatorThatAddsErrors, on: :create)
     topic = Topic.new
     assert topic.invalid?(:create), "Validation does run on create if 'on' is set to create"
-    assert topic.errors[:base].include?(ERROR_MESSAGE)
+    assert_includes topic.errors[:base], ERROR_MESSAGE
   end
 
   test "with a class that adds errors on multiple contexts and validating a new model" do
@@ -48,10 +50,10 @@ class ValidationsContextTest < ActiveModel::TestCase
     assert topic.valid?, "Validation ran with no context given when 'on' is set to context1 and context2"
 
     assert topic.invalid?(:context1), "Validation did not run on context1 when 'on' is set to context1 and context2"
-    assert topic.errors[:base].include?(ERROR_MESSAGE)
+    assert_includes topic.errors[:base], ERROR_MESSAGE
 
     assert topic.invalid?(:context2), "Validation did not run on context2 when 'on' is set to context1 and context2"
-    assert topic.errors[:base].include?(ERROR_MESSAGE)
+    assert_includes topic.errors[:base], ERROR_MESSAGE
   end
 
   test "with a class that validating a model for a multiple contexts" do
@@ -62,7 +64,7 @@ class ValidationsContextTest < ActiveModel::TestCase
     assert topic.valid?, "Validation ran with no context given when 'on' is set to context1 and context2"
 
     assert topic.invalid?([:context1, :context2]), "Validation did not run on context1 when 'on' is set to context1 and context2"
-    assert topic.errors[:base].include?(ERROR_MESSAGE)
-    assert topic.errors[:base].include?(ANOTHER_ERROR_MESSAGE)
+    assert_includes topic.errors[:base], ERROR_MESSAGE
+    assert_includes topic.errors[:base], ANOTHER_ERROR_MESSAGE
   end
 end
diff --git a/activemodel/test/cases/validations/with_validation_test.rb b/activemodel/test/cases/validations/with_validation_test.rb
index c73580138d..13ef5e6a31 100644
--- a/activemodel/test/cases/validations/with_validation_test.rb
+++ b/activemodel/test/cases/validations/with_validation_test.rb
@@ -1,9 +1,10 @@
-require 'cases/helper'
+# frozen_string_literal: true
 
-require 'models/topic'
+require "cases/helper"
 
-class ValidatesWithTest < ActiveModel::TestCase
+require "models/topic"
 
+class ValidatesWithTest < ActiveModel::TestCase
   def teardown
     Topic.clear_validators!
   end
@@ -52,7 +53,7 @@ class ValidatesWithTest < ActiveModel::TestCase
     Topic.validates_with(ValidatorThatAddsErrors)
     topic = Topic.new
     assert topic.invalid?, "A class that adds errors causes the record to be invalid"
-    assert topic.errors[:base].include?(ERROR_MESSAGE)
+    assert_includes topic.errors[:base], ERROR_MESSAGE
   end
 
   test "with a class that returns valid" do
@@ -65,45 +66,19 @@ class ValidatesWithTest < ActiveModel::TestCase
     Topic.validates_with(ValidatorThatAddsErrors, OtherValidatorThatAddsErrors)
     topic = Topic.new
     assert topic.invalid?
-    assert topic.errors[:base].include?(ERROR_MESSAGE)
-    assert topic.errors[:base].include?(OTHER_ERROR_MESSAGE)
-  end
-
-  test "with if statements that return false" do
-    Topic.validates_with(ValidatorThatAddsErrors, if: "1 == 2")
-    topic = Topic.new
-    assert topic.valid?
-  end
-
-  test "with if statements that return true" do
-    Topic.validates_with(ValidatorThatAddsErrors, if: "1 == 1")
-    topic = Topic.new
-    assert topic.invalid?
-    assert topic.errors[:base].include?(ERROR_MESSAGE)
-  end
-
-  test "with unless statements that return true" do
-    Topic.validates_with(ValidatorThatAddsErrors, unless: "1 == 1")
-    topic = Topic.new
-    assert topic.valid?
-  end
-
-  test "with unless statements that returns false" do
-    Topic.validates_with(ValidatorThatAddsErrors, unless: "1 == 2")
-    topic = Topic.new
-    assert topic.invalid?
-    assert topic.errors[:base].include?(ERROR_MESSAGE)
+    assert_includes topic.errors[:base], ERROR_MESSAGE
+    assert_includes topic.errors[:base], OTHER_ERROR_MESSAGE
   end
 
   test "passes all configuration options to the validator class" do
     topic = Topic.new
     validator = Minitest::Mock.new
-    validator.expect(:new, validator, [{foo: :bar, if: "1 == 1", class: Topic}])
+    validator.expect(:new, validator, [{ foo: :bar, if: :condition_is_true, class: Topic }])
     validator.expect(:validate, nil, [topic])
     validator.expect(:is_a?, false, [Symbol])
     validator.expect(:is_a?, false, [String])
 
-    Topic.validates_with(validator, if: "1 == 1", foo: :bar)
+    Topic.validates_with(validator, if: :condition_is_true, foo: :bar)
     assert topic.valid?
     validator.verify
   end
@@ -112,7 +87,7 @@ class ValidatesWithTest < ActiveModel::TestCase
     Topic.validates_with(ValidatorThatValidatesOptions, field: :first_name)
     topic = Topic.new
     assert topic.invalid?
-    assert topic.errors[:base].include?(ERROR_MESSAGE)
+    assert_includes topic.errors[:base], ERROR_MESSAGE
   end
 
   test "validates_with each validator" do
@@ -160,7 +135,7 @@ class ValidatesWithTest < ActiveModel::TestCase
 
     topic = Topic.new
     assert !topic.valid?
-    assert_equal ['is missing'], topic.errors[:title]
+    assert_equal ["is missing"], topic.errors[:title]
   end
 
   test "optionally pass in the attribute being validated when validating with an instance method" do
@@ -169,6 +144,6 @@ class ValidatesWithTest < ActiveModel::TestCase
     topic = Topic.new title: "foo"
     assert !topic.valid?
     assert topic.errors[:title].empty?
-    assert_equal ['is missing'], topic.errors[:content]
+    assert_equal ["is missing"], topic.errors[:content]
   end
 end
diff --git a/activemodel/test/cases/validations_test.rb b/activemodel/test/cases/validations_test.rb
index 2a4e9f842f..ab8c41bbd0 100644
--- a/activemodel/test/cases/validations_test.rb
+++ b/activemodel/test/cases/validations_test.rb
@@ -1,11 +1,13 @@
-require 'cases/helper'
+# frozen_string_literal: true
 
-require 'models/topic'
-require 'models/reply'
-require 'models/custom_reader'
+require "cases/helper"
 
-require 'active_support/json'
-require 'active_support/xml_mini'
+require "models/topic"
+require "models/reply"
+require "models/custom_reader"
+
+require "active_support/json"
+require "active_support/xml_mini"
 
 class ValidationsTest < ActiveModel::TestCase
   class CustomStrictValidationException < StandardError; end
@@ -51,10 +53,10 @@ class ValidationsTest < ActiveModel::TestCase
     r = Reply.new
     r.valid?
 
-    errors = r.errors.collect {|attr, messages| [attr.to_s, messages]}
+    errors = r.errors.collect { |attr, messages| [attr.to_s, messages] }
 
-    assert errors.include?(["title", "is Empty"])
-    assert errors.include?(["content", "is Empty"])
+    assert_includes errors, ["title", "is Empty"]
+    assert_includes errors, ["content", "is Empty"]
   end
 
   def test_multiple_errors_per_attr_iteration_with_full_error_composition
@@ -86,8 +88,8 @@ class ValidationsTest < ActiveModel::TestCase
 
     assert_equal ["Reply is not dignifying"], r.errors[:base]
 
-    assert errors.include?("Title is Empty")
-    assert errors.include?("Reply is not dignifying")
+    assert_includes errors, "Title is Empty"
+    assert_includes errors, "Reply is not dignifying"
     assert_equal 2, r.errors.count
   end
 
@@ -101,8 +103,8 @@ class ValidationsTest < ActiveModel::TestCase
 
     assert_equal ["is invalid"], r.errors[:base]
 
-    assert errors.include?("Title is Empty")
-    assert errors.include?("is invalid")
+    assert_includes errors, "Title is Empty"
+    assert_includes errors, "is invalid"
 
     assert_equal 2, r.errors.count
   end
@@ -116,7 +118,7 @@ class ValidationsTest < ActiveModel::TestCase
   def test_validates_each
     hits = 0
     Topic.validates_each(:title, :content, [:title, :content]) do |record, attr|
-      record.errors.add attr, 'gotcha'
+      record.errors.add attr, "gotcha"
       hits += 1
     end
     t = Topic.new("title" => "valid", "content" => "whatever")
@@ -129,7 +131,7 @@ class ValidationsTest < ActiveModel::TestCase
   def test_validates_each_custom_reader
     hits = 0
     CustomReader.validates_each(:title, :content, [:title, :content]) do |record, attr|
-      record.errors.add attr, 'gotcha'
+      record.errors.add attr, "gotcha"
       hits += 1
     end
     t = CustomReader.new("title" => "valid", "content" => "whatever")
@@ -170,7 +172,7 @@ class ValidationsTest < ActiveModel::TestCase
       # A common mistake -- we meant to call 'validates'
       Topic.validate :title, presence: true
     end
-    message = 'Unknown key: :presence. Valid keys are: :on, :if, :unless, :prepend. Perhaps you meant to call `validates` instead of `validate`?'
+    message = "Unknown key: :presence. Valid keys are: :on, :if, :unless, :prepend. Perhaps you meant to call `validates` instead of `validate`?"
     assert_equal message, error.message
   end
 
@@ -198,9 +200,9 @@ class ValidationsTest < ActiveModel::TestCase
     end
 
     assert_nothing_raised do
-      klass.validate :validator_a, if: ->{ true }
+      klass.validate :validator_a, if: -> { true }
       klass.validate :validator_b, prepend: true
-      klass.validate :validator_c, unless: ->{ true }
+      klass.validate :validator_c, unless: -> { true }
     end
 
     t = klass.new
@@ -233,25 +235,25 @@ class ValidationsTest < ActiveModel::TestCase
     assert t.invalid?
     assert_equal "can't be blank", t.errors["title"].first
     Topic.validates_presence_of :title, :author_name
-    Topic.validate {errors.add('author_email_address', 'will never be valid')}
+    Topic.validate { errors.add("author_email_address", "will never be valid") }
     Topic.validates_length_of :title, :content, minimum: 2
 
-    t = Topic.new title: ''
+    t = Topic.new title: ""
     assert t.invalid?
 
     assert_equal :title, key = t.errors.keys[0]
     assert_equal "can't be blank", t.errors[key][0]
-    assert_equal 'is too short (minimum is 2 characters)', t.errors[key][1]
+    assert_equal "is too short (minimum is 2 characters)", t.errors[key][1]
     assert_equal :author_name, key = t.errors.keys[1]
     assert_equal "can't be blank", t.errors[key][0]
     assert_equal :author_email_address, key = t.errors.keys[2]
-    assert_equal 'will never be valid', t.errors[key][0]
+    assert_equal "will never be valid", t.errors[key][0]
     assert_equal :content, key = t.errors.keys[3]
-    assert_equal 'is too short (minimum is 2 characters)', t.errors[key][0]
+    assert_equal "is too short (minimum is 2 characters)", t.errors[key][0]
   end
 
   def test_validation_with_if_and_on
-    Topic.validates_presence_of :title, if: Proc.new{|x| x.author_name = "bad"; true }, on: :update
+    Topic.validates_presence_of :title, if: Proc.new { |x| x.author_name = "bad"; true }, on: :update
 
     t = Topic.new(title: "")
 
@@ -271,7 +273,7 @@ class ValidationsTest < ActiveModel::TestCase
     assert t.invalid?
     assert t.errors[:title].any?
 
-    t.title = 'Things are going to change'
+    t.title = "Things are going to change"
     assert !t.invalid?
   end
 
@@ -332,9 +334,9 @@ class ValidationsTest < ActiveModel::TestCase
     assert topic.invalid?
     assert_equal 3, topic.errors.size
 
-    topic.title = 'Some Title'
-    topic.author_name = 'Some Author'
-    topic.content = 'Some Content Whose Length is more than 10.'
+    topic.title = "Some Title"
+    topic.author_name = "Some Author"
+    topic.content = "Some Content Whose Length is more than 10."
     assert topic.valid?
   end
 
@@ -440,7 +442,7 @@ class ValidationsTest < ActiveModel::TestCase
     assert duped.invalid?
 
     topic.title = nil
-    duped.title = 'Mathematics'
+    duped.title = "Mathematics"
     assert topic.invalid?
     assert duped.valid?
   end
@@ -448,7 +450,7 @@ class ValidationsTest < ActiveModel::TestCase
   def test_validation_with_message_as_proc_that_takes_a_record_as_a_parameter
     Topic.validates_presence_of(:title, message: proc { |record| "You have failed me for the last time, #{record.author_name}." })
 
-    t = Topic.new(author_name: 'Admiral')
+    t = Topic.new(author_name: "Admiral")
     assert t.invalid?
     assert_equal ["You have failed me for the last time, Admiral."], t.errors[:title]
   end
@@ -456,7 +458,7 @@ class ValidationsTest < ActiveModel::TestCase
   def test_validation_with_message_as_proc_that_takes_record_and_data_as_a_parameters
     Topic.validates_presence_of(:title, message: proc { |record, data| "#{data[:attribute]} is missing. You have failed me for the last time, #{record.author_name}." })
 
-    t = Topic.new(author_name: 'Admiral')
+    t = Topic.new(author_name: "Admiral")
     assert t.invalid?
     assert_equal ["Title is missing. You have failed me for the last time, Admiral."], t.errors[:title]
   end
diff --git a/activemodel/test/models/account.rb b/activemodel/test/models/account.rb
index eed668d38f..40408e5708 100644
--- a/activemodel/test/models/account.rb
+++ b/activemodel/test/models/account.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Account
   include ActiveModel::ForbiddenAttributesProtection
 
diff --git a/activemodel/test/models/blog_post.rb b/activemodel/test/models/blog_post.rb
index 46eba857df..d4b02eeaa7 100644
--- a/activemodel/test/models/blog_post.rb
+++ b/activemodel/test/models/blog_post.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module Blog
   def self.use_relative_model_naming?
     true
diff --git a/activemodel/test/models/contact.rb b/activemodel/test/models/contact.rb
index 113ab0bc1f..c40a6d6f0e 100644
--- a/activemodel/test/models/contact.rb
+++ b/activemodel/test/models/contact.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Contact
   extend ActiveModel::Naming
   include ActiveModel::Conversion
diff --git a/activemodel/test/models/custom_reader.rb b/activemodel/test/models/custom_reader.rb
index 2fbcf79c3d..df605e93d9 100644
--- a/activemodel/test/models/custom_reader.rb
+++ b/activemodel/test/models/custom_reader.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class CustomReader
   include ActiveModel::Validations
 
@@ -12,4 +14,4 @@ class CustomReader
   def read_attribute_for_validation(key)
     @data[key]
   end
-end
\ No newline at end of file
+end
diff --git a/activemodel/test/models/helicopter.rb b/activemodel/test/models/helicopter.rb
index 933f3c463a..fe82c463d3 100644
--- a/activemodel/test/models/helicopter.rb
+++ b/activemodel/test/models/helicopter.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Helicopter
   include ActiveModel::Conversion
 end
diff --git a/activemodel/test/models/person.rb b/activemodel/test/models/person.rb
index e896e90f98..8dd8ceadad 100644
--- a/activemodel/test/models/person.rb
+++ b/activemodel/test/models/person.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Person
   include ActiveModel::Validations
   extend  ActiveModel::Translation
@@ -7,6 +9,10 @@ class Person
   def condition_is_true
     true
   end
+
+  def condition_is_false
+    false
+  end
 end
 
 class Person::Gender
diff --git a/activemodel/test/models/person_with_validator.rb b/activemodel/test/models/person_with_validator.rb
index 505ed880c1..44e78cbc29 100644
--- a/activemodel/test/models/person_with_validator.rb
+++ b/activemodel/test/models/person_with_validator.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class PersonWithValidator
   include ActiveModel::Validations
 
diff --git a/activemodel/test/models/reply.rb b/activemodel/test/models/reply.rb
index b77910e671..6bb18f95fe 100644
--- a/activemodel/test/models/reply.rb
+++ b/activemodel/test/models/reply.rb
@@ -1,4 +1,6 @@
-require 'models/topic'
+# frozen_string_literal: true
+
+require "models/topic"
 
 class Reply < Topic
   validate :errors_on_empty_content
diff --git a/activemodel/test/models/sheep.rb b/activemodel/test/models/sheep.rb
index 7aba055c4f..30dd9ce192 100644
--- a/activemodel/test/models/sheep.rb
+++ b/activemodel/test/models/sheep.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Sheep
   extend ActiveModel::Naming
 end
diff --git a/activemodel/test/models/topic.rb b/activemodel/test/models/topic.rb
index fed50bc361..b0af00ee45 100644
--- a/activemodel/test/models/topic.rb
+++ b/activemodel/test/models/topic.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Topic
   include ActiveModel::Validations
   include ActiveModel::Validations::Callbacks
@@ -21,7 +23,7 @@ class Topic
     true
   end
 
-  def condition_is_true_but_its_not
+  def condition_is_false
     false
   end
 
@@ -36,9 +38,4 @@ class Topic
   def my_validation_with_arg(attr)
     errors.add attr, "is missing" unless send(attr)
   end
-
-  def my_word_tokenizer(str)
-   str.scan(/\w+/)
-  end
-
 end
diff --git a/activemodel/test/models/track_back.rb b/activemodel/test/models/track_back.rb
index 768c96ecf0..728a022db5 100644
--- a/activemodel/test/models/track_back.rb
+++ b/activemodel/test/models/track_back.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Post
   class TrackBack
     def to_model
@@ -8,4 +10,4 @@ class Post
   class NamedTrackBack
     extend ActiveModel::Naming
   end
-end
\ No newline at end of file
+end
diff --git a/activemodel/test/models/user.rb b/activemodel/test/models/user.rb
index 1ec6001c48..e98fd8a0a1 100644
--- a/activemodel/test/models/user.rb
+++ b/activemodel/test/models/user.rb
@@ -1,7 +1,9 @@
+# frozen_string_literal: true
+
 class User
   extend ActiveModel::Callbacks
   include ActiveModel::SecurePassword
-  
+
   define_model_callbacks :create
 
   has_secure_password
diff --git a/activemodel/test/models/visitor.rb b/activemodel/test/models/visitor.rb
index 22ad1a3c3d..9da004ffcc 100644
--- a/activemodel/test/models/visitor.rb
+++ b/activemodel/test/models/visitor.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Visitor
   extend ActiveModel::Callbacks
   include ActiveModel::SecurePassword
diff --git a/activemodel/test/validators/email_validator.rb b/activemodel/test/validators/email_validator.rb
index cff47ac230..0c634d8659 100644
--- a/activemodel/test/validators/email_validator.rb
+++ b/activemodel/test/validators/email_validator.rb
@@ -1,6 +1,8 @@
+# frozen_string_literal: true
+
 class EmailValidator < ActiveModel::EachValidator
   def validate_each(record, attribute, value)
     record.errors[attribute] << (options[:message] || "is not an email") unless
-      value =~ /^([^@\s]+)@((?:[-a-z0-9]+\.)+[a-z]{2,})$/i
+      /\A([^@\s]+)@((?:[-a-z0-9]+\.)+[a-z]{2,})\z/i.match?(value)
   end
-end
\ No newline at end of file
+end
diff --git a/activemodel/test/validators/namespace/email_validator.rb b/activemodel/test/validators/namespace/email_validator.rb
index 57e2793ce2..e7815d92dc 100644
--- a/activemodel/test/validators/namespace/email_validator.rb
+++ b/activemodel/test/validators/namespace/email_validator.rb
@@ -1,4 +1,6 @@
-require 'validators/email_validator'
+# frozen_string_literal: true
+
+require "validators/email_validator"
 
 module Namespace
   class EmailValidator < ::EmailValidator
diff --git a/activerecord/CHANGELOG.md b/activerecord/CHANGELOG.md
index 0bd3c2e78c..cbbfad615d 100644
--- a/activerecord/CHANGELOG.md
+++ b/activerecord/CHANGELOG.md
@@ -1,35 +1,574 @@
-*   Ensure hashes can be assigned to attributes created using `composed_of`.
-    Fixes #25210.
+*   Use `count(:all)` in `HasManyAssociation#count_records` to prevent invalid
+    SQL queries for association counting.
+
+    *Klas Eskilson*
+
+*   Fix to invoke callbacks when using `update_attribute`.
+
+    *Mike Busch*
+
+*   Fix `count(:all)` to correctly work `distinct` with custom SELECT list.
+
+    *Ryuta Kamizono*
+
+*   Using subselect for `delete_all` with `limit` or `offset`.
+
+    *Ryuta Kamizono*
+
+*   Undefine attribute methods on descendants when resetting column
+    information.
+
+    *Chris Salzberg*
+
+*   Log database query callers
+
+    Add `verbose_query_logs` configuration option to display the caller
+    of database queries in the log to facilitate N+1 query resolution
+    and other debugging.
+
+    Enabled in development only for new and upgraded applications. Not
+    recommended for use in the production environment since it relies
+    on Ruby's `Kernel#caller_locations` which is fairly slow.
+
+    *Olivier Lacan*
+
+*   Fix conflicts `counter_cache` with `touch: true` by optimistic locking.
+
+    ```
+    # create_table :posts do |t|
+    #   t.integer :comments_count, default: 0
+    #   t.integer :lock_version
+    #   t.timestamps
+    # end
+    class Post < ApplicationRecord
+    end
+
+    # create_table :comments do |t|
+    #   t.belongs_to :post
+    # end
+    class Comment < ApplicationRecord
+      belongs_to :post, touch: true, counter_cache: true
+    end
+    ```
+
+    Before:
+    ```
+    post = Post.create!
+    # => begin transaction
+         INSERT INTO "posts" ("created_at", "updated_at", "lock_version")
+         VALUES ("2017-12-11 21:27:11.387397", "2017-12-11 21:27:11.387397", 0)
+         commit transaction
+
+    comment = Comment.create!(post: post)
+    # => begin transaction
+         INSERT INTO "comments" ("post_id") VALUES (1)
+
+         UPDATE "posts" SET "comments_count" = COALESCE("comments_count", 0) + 1,
+         "lock_version" = COALESCE("lock_version", 0) + 1 WHERE "posts"."id" = 1
+
+         UPDATE "posts" SET "updated_at" = '2017-12-11 21:27:11.398330',
+         "lock_version" = 1 WHERE "posts"."id" = 1 AND "posts"."lock_version" = 0
+         rollback transaction
+    # => ActiveRecord::StaleObjectError: Attempted to touch a stale object: Post.
+
+    Comment.take.destroy!
+    # => begin transaction
+         DELETE FROM "comments" WHERE "comments"."id" = 1
+
+         UPDATE "posts" SET "comments_count" = COALESCE("comments_count", 0) - 1,
+         "lock_version" = COALESCE("lock_version", 0) + 1 WHERE "posts"."id" = 1
+
+         UPDATE "posts" SET "updated_at" = '2017-12-11 21:42:47.785901',
+         "lock_version" = 1 WHERE "posts"."id" = 1 AND "posts"."lock_version" = 0
+         rollback transaction
+    # => ActiveRecord::StaleObjectError: Attempted to touch a stale object: Post.
+    ```
+
+    After:
+    ```
+    post = Post.create!
+    # => begin transaction
+         INSERT INTO "posts" ("created_at", "updated_at", "lock_version")
+         VALUES ("2017-12-11 21:27:11.387397", "2017-12-11 21:27:11.387397", 0)
+         commit transaction
+
+    comment = Comment.create!(post: post)
+    # => begin transaction
+         INSERT INTO "comments" ("post_id") VALUES (1)
+
+         UPDATE "posts" SET "comments_count" = COALESCE("comments_count", 0) + 1,
+         "lock_version" = COALESCE("lock_version", 0) + 1,
+         "updated_at" = '2017-12-11 21:37:09.802642' WHERE "posts"."id" = 1
+         commit transaction
+
+    comment.destroy!
+    # => begin transaction
+         DELETE FROM "comments" WHERE "comments"."id" = 1
+
+         UPDATE "posts" SET "comments_count" = COALESCE("comments_count", 0) - 1,
+         "lock_version" = COALESCE("lock_version", 0) + 1,
+         "updated_at" = '2017-12-11 21:39:02.685520' WHERE "posts"."id" = 1
+         commit transaction
+    ```
+
+    Fixes #31199.
+
+    *bogdanvlviv*
+
+*   Add support for PostgreSQL operator classes to `add_index`.
+
+    Example:
+
+        add_index :users, :name, using: :gist, opclass: { name: :gist_trgm_ops }
+
+    *Greg Navis*
+
+*   Don't allow scopes to be defined which conflict with instance methods on `Relation`.
+
+    Fixes #31120.
+
+    *kinnrot*
+
+
+## Rails 5.2.0.beta2 (November 28, 2017) ##
+
+*   No changes.
+
+
+## Rails 5.2.0.beta1 (November 27, 2017) ##
+
+*   Add new error class `QueryCanceled` which will be raised
+    when canceling statement due to user request.
+
+    *Ryuta Kamizono*
+
+*   Add `#up_only` to database migrations for code that is only relevant when
+    migrating up, e.g. populating a new column.
+
+    *Rich Daley*
+
+*   Require raw SQL fragments to be explicitly marked when used in
+    relation query methods.
+
+    Before:
+    ```
+    Article.order("LENGTH(title)")
+    ```
+
+    After:
+    ```
+    Article.order(Arel.sql("LENGTH(title)"))
+    ```
+
+    This prevents SQL injection if applications use the [strongly
+    discouraged] form `Article.order(params[:my_order])`, under the
+    mistaken belief that only column names will be accepted.
+
+    Raw SQL strings will now cause a deprecation warning, which will
+    become an UnknownAttributeReference error in Rails 6.0. Applications
+    can opt in to the future behavior by setting `allow_unsafe_raw_sql`
+    to `:disabled`.
+
+    Common and judged-safe string values (such as simple column
+    references) are unaffected:
+    ```
+    Article.order("title DESC")
+    ```
+
+    *Ben Toews*
+
+*   `update_all` will now pass its values to `Type#cast` before passing them to
+    `Type#serialize`. This means that `update_all(foo: 'true')` will properly
+    persist a boolean.
 
     *Sean Griffin*
 
-*   Fix logging edge case where if an attribute was of the binary type and
-    was provided as a Hash.
+*   Add new error class `StatementTimeout` which will be raised
+    when statement timeout exceeded.
+
+    *Ryuta Kamizono*
+
+*   Fix `bin/rails db:migrate` with specified `VERSION`.
+    `bin/rails db:migrate` with empty VERSION behaves as without `VERSION`.
+    Check a format of `VERSION`: Allow a migration version number
+    or name of a migration file. Raise error if format of `VERSION` is invalid.
+    Raise error if target migration doesn't exist.
+
+    *bogdanvlviv*
+
+*   Fixed a bug where column orders for an index weren't written to
+    `db/schema.rb` when using the sqlite adapter.
+
+    Fixes #30902.
+
+    *Paul Kuruvilla*
+
+*   Remove deprecated method `#sanitize_conditions`.
+
+    *Rafael Mendonça França*
+
+*   Remove deprecated method `#scope_chain`.
+
+    *Rafael Mendonça França*
+
+*   Remove deprecated configuration `.error_on_ignored_order_or_limit`.
+
+    *Rafael Mendonça França*
+
+*   Remove deprecated arguments from `#verify!`.
+
+    *Rafael Mendonça França*
+
+*   Remove deprecated argument `name` from `#indexes`.
+
+    *Rafael Mendonça França*
+
+*   Remove deprecated method `ActiveRecord::Migrator.schema_migrations_table_name`.
+
+    *Rafael Mendonça França*
+
+*   Remove deprecated method `supports_primary_key?`.
+
+    *Rafael Mendonça França*
+
+*   Remove deprecated method `supports_migrations?`.
+
+    *Rafael Mendonça França*
+
+*   Remove deprecated methods `initialize_schema_migrations_table` and `initialize_internal_metadata_table`.
+
+    *Rafael Mendonça França*
+
+*   Raises when calling `lock!` in a dirty record.
+
+    *Rafael Mendonça França*
+
+*   Remove deprecated support to passing a class to `:class_name` on associations.
+
+    *Rafael Mendonça França*
+
+*   Remove deprecated argument `default` from `index_name_exists?`.
+
+    *Rafael Mendonça França*
+
+*   Remove deprecated support to `quoted_id` when typecasting an Active Record object.
+
+    *Rafael Mendonça França*
+
+*   Fix `bin/rails db:setup` and `bin/rails db:test:prepare` create  wrong
+    ar_internal_metadata's data for a test database.
+
+    Before:
+    ```
+    $ RAILS_ENV=test rails dbconsole
+    > SELECT * FROM ar_internal_metadata;
+    key|value|created_at|updated_at
+    environment|development|2017-09-11 23:14:10.815679|2017-09-11 23:14:10.815679
+    ```
+
+    After:
+    ```
+    $ RAILS_ENV=test rails dbconsole
+    > SELECT * FROM ar_internal_metadata;
+    key|value|created_at|updated_at
+    environment|test|2017-09-11 23:14:10.815679|2017-09-11 23:14:10.815679
+    ```
+
+    Fixes #26731.
+
+    *bogdanvlviv*
+
+*   Fix longer sequence name detection for serial columns.
+
+    Fixes #28332.
+
+    *Ryuta Kamizono*
+
+*   MySQL: Don't lose `auto_increment: true` in the `db/schema.rb`.
+
+    Fixes #30894.
+
+    *Ryuta Kamizono*
+
+*   Fix `COUNT(DISTINCT ...)` for `GROUP BY` with `ORDER BY` and `LIMIT`.
+
+    Fixes #30886.
+
+    *Ryuta Kamizono*
+
+*   PostgreSQL `tsrange` now preserves subsecond precision.
+
+    PostgreSQL 9.1+ introduced range types, and Rails added support for using
+    this datatype in Active Record. However, the serialization of
+    `PostgreSQL::OID::Range` was incomplete, because it did not properly
+    cast the bounds that make up the range. This led to subseconds being
+    dropped in SQL commands:
+
+    Before:
+
+        connection.type_cast(tsrange.serialize(range_value))
+        # => "[2010-01-01 13:30:00 UTC,2011-02-02 19:30:00 UTC)"
+
+    Now:
+
+        connection.type_cast(tsrange.serialize(range_value))
+        # => "[2010-01-01 13:30:00.670277,2011-02-02 19:30:00.745125)"
+
+    *Thomas Cannon*
+
+*   Passing a `Set` to `Relation#where` now behaves the same as passing an
+    array.
+
+    *Sean Griffin*
+
+*   Use given algorithm while removing index from database.
+
+    Fixes #24190.
+
+    *Mehmet Emin İNAÇ*
+
+*   Update payload names for `sql.active_record` instrumentation to be
+    more descriptive.
+
+    Fixes #30586.
+
+    *Jeremy Green*
+
+*   Add new error class `LockWaitTimeout` which will be raised
+    when lock wait timeout exceeded.
+
+    *Gabriel Courtemanche*
+
+*   Remove deprecated `#migration_keys`.
+
+    *Ryuta Kamizono*
+
+*   Automatically guess the inverse associations for STI.
+
+    *Yuichiro Kaneko*
+
+*   Ensure `sum` honors `distinct` on `has_many :through` associations
+
+    Fixes #16791.
+
+    *Aaron Wortham*
+
+*   Add `binary` fixture helper method.
+
+    *Atsushi Yoshida*
+
+*   When using `Relation#or`, extract the common conditions and put them before the OR condition.
+
+    *Maxime Handfield Lapointe*
+
+*   `Relation#or` now accepts two relations who have different values for
+    `references` only, as `references` can be implicitly called by `where`.
+
+    Fixes #29411.
+
+    *Sean Griffin*
+
+*   `ApplicationRecord` is no longer generated when generating models. If you
+    need to generate it, it can be created with `rails g application_record`.
+
+    *Lisa Ugray*
+
+*   Fix `COUNT(DISTINCT ...)` with `ORDER BY` and `LIMIT` to keep the existing select list.
+
+    *Ryuta Kamizono*
+
+*   When a `has_one` association is destroyed by `dependent: destroy`,
+    `destroyed_by_association` will now be set to the reflection, matching the
+    behaviour of `has_many` associations.
+
+    *Lisa Ugray*
+
+*   Fix `unscoped(where: [columns])` removing the wrong bind values
+
+    When the `where` is called on a relation after a `or`, unscoping the column of that later `where` removed
+    bind values used by the `or` instead. (possibly other cases too)
+
+    ```
+    Post.where(id: 1).or(Post.where(id: 2)).where(foo: 3).unscope(where: :foo).to_sql
+    # Currently:
+    #     SELECT "posts".* FROM "posts" WHERE ("posts"."id" = 2 OR "posts"."id" = 3)
+    # With fix:
+    #     SELECT "posts".* FROM "posts" WHERE ("posts"."id" = 1 OR "posts"."id" = 2)
+    ```
+
+    *Maxime Handfield Lapointe*
+
+*   Values constructed using multi-parameter assignment will now use the
+    post-type-cast value for rendering in single-field form inputs.
+
+    *Sean Griffin*
+
+*   `Relation#joins` is no longer affected by the target model's
+    `current_scope`, with the exception of `unscoped`.
+
+    Fixes #29338.
+
+    *Sean Griffin*
+
+*   Change sqlite3 boolean serialization to use 1 and 0
+
+    SQLite natively recognizes 1 and 0 as true and false, but does not natively
+    recognize 't' and 'f' as was previously serialized.
+
+    This change in serialization requires a migration of stored boolean data
+    for SQLite databases, so it's implemented behind a configuration flag
+    whose default false value is deprecated.
+
+    *Lisa Ugray*
+
+*   Skip query caching when working with batches of records (`find_each`, `find_in_batches`,
+    `in_batches`).
+
+    Previously, records would be fetched in batches, but all records would be retained in memory
+    until the end of the request or job.
+
+    *Eugene Kenny*
+
+*   Prevent errors raised by `sql.active_record` notification subscribers from being converted into
+    `ActiveRecord::StatementInvalid` exceptions.
+
+    *Dennis Taylor*
+
+*   Fix eager loading/preloading association with scope including joins.
+
+    Fixes #28324.
+
+    *Ryuta Kamizono*
+
+*   Fix transactions to apply state to child transactions
+
+    Previously, if you had a nested transaction and the outer transaction was rolledback, the record from the
+    inner transaction would still be marked as persisted.
+
+    This change fixes that by applying the state of the parent transaction to the child transaction when the
+    parent transaction is rolledback. This will correctly mark records from the inner transaction as not persisted.
+
+    *Eileen M. Uchitelle*, *Aaron Patterson*
+
+*   Deprecate `set_state` method in `TransactionState`
+
+    Deprecated the `set_state` method in favor of setting the state via specific methods. If you need to mark the
+    state of the transaction you can now use `rollback!`, `commit!` or `nullify!` instead of
+    `set_state(:rolledback)`, `set_state(:committed)`, or `set_state(nil)`.
+
+    *Eileen M. Uchitelle*, *Aaron Patterson*
+
+*   Deprecate delegating to `arel` in `Relation`.
+
+    *Ryuta Kamizono*
+
+*   Fix eager loading to respect `store_full_sti_class` setting.
+
+    *Ryuta Kamizono*
+
+*   Query cache was unavailable when entering the `ActiveRecord::Base.cache` block
+    without being connected.
+
+    *Tsukasa Oishi*
+
+*   Previously, when building records using a `has_many :through` association,
+    if the child records were deleted before the parent was saved, they would
+    still be persisted. Now, if child records are deleted before the parent is saved
+    on a `has_many :through` association, the child records will not be persisted.
+
+    *Tobias Kraze*
+
+*   Merging two relations representing nested joins no longer transforms the joins of
+    the merged relation into LEFT OUTER JOIN. Example to clarify:
+
+    ```
+    Author.joins(:posts).merge(Post.joins(:comments))
+    # Before the change:
+    #=> SELECT ... FROM authors INNER JOIN posts ON ... LEFT OUTER JOIN comments ON...
+
+    # After the change:
+    #=> SELECT ... FROM authors INNER JOIN posts ON ... INNER JOIN comments ON...
+    ```
+
+    TODO: Add to the Rails 5.2 upgrade guide
+
+    *Maxime Handfield Lapointe*
+
+*   `ActiveRecord::Persistence#touch` does not work well when optimistic locking enabled and
+    `locking_column`, without default value, is null in the database.
+
+    *bogdanvlviv*
+
+*   Fix destroying existing object does not work well when optimistic locking enabled and
+    `locking_column` is null in the database.
+
+    *bogdanvlviv*
+
+*   Use bulk INSERT to insert fixtures for better performance.
+
+    *Kir Shatrov*
+
+*   Prevent creation of bind param if casted value is nil.
+
+    *Ryuta Kamizono*
+
+*   Deprecate passing arguments and block at the same time to `count` and `sum` in `ActiveRecord::Calculations`.
+
+    *Ryuta Kamizono*
+
+*   Loading model schema from database is now thread-safe.
+
+    Fixes #28589.
+
+    *Vikrant Chaudhary*, *David Abdemoulaie*
+
+*   Add `ActiveRecord::Base#cache_version` to support recyclable cache keys via the new versioned entries
+    in `ActiveSupport::Cache`. This also means that `ActiveRecord::Base#cache_key` will now return a stable key
+    that does not include a timestamp any more.
+
+    NOTE: This feature is turned off by default, and `#cache_key` will still return cache keys with timestamps
+    until you set `ActiveRecord::Base.cache_versioning = true`. That's the setting for all new apps on Rails 5.2+
+
+    *DHH*
+
+*   Respect `SchemaDumper.ignore_tables` in rake tasks for databases structure dump
+
+    *Rusty Geldmacher*, *Guillermo Iguaran*
+
+*   Add type caster to `RuntimeReflection#alias_name`
+
+    Fixes #28959.
 
     *Jon Moss*
 
-*   Handle JSON deserialization correctly if the column default from database
-    adapter returns `''` instead of `nil`.
+*   Deprecate `supports_statement_cache?`.
 
-    *Johannes Opper*
+    *Ryuta Kamizono*
 
-*   Introduce ActiveRecord::TransactionSerializationError for catching
-    transaction serialization failures or deadlocks.
+*   Raise error `UnknownMigrationVersionError` on the movement of migrations
+    when the current migration does not exist.
 
-    *Erol Fornoles*
+    *bogdanvlviv*
 
-*   PostgreSQL: Fix db:structure:load silent failure on SQL error
+*   Fix `bin/rails db:forward` first migration.
 
-    The command line flag "-v ON_ERROR_STOP=1" should be used
-    when invoking psql to make sure errors are not suppressed.
+    *bogdanvlviv*
 
-    Example:
+*   Support Descending Indexes for MySQL.
+
+    MySQL 8.0.1 and higher supports descending indexes: `DESC` in an index definition is no longer ignored.
+    See https://dev.mysql.com/doc/refman/8.0/en/descending-indexes.html.
+
+    *Ryuta Kamizono*
+
+*   Fix inconsistency with changed attributes when overriding AR attribute reader.
 
-        psql -v ON_ERROR_STOP=1 -q -f awesome-file.sql my-app-db
+    *bogdanvlviv*
 
-    Fixes #23818.
+*   When calling the dynamic fixture accessor method with no arguments, it now returns all fixtures of this type.
+    Previously this method always returned an empty array.
 
-    *Ralin Chimev*
+    *Kevin McPhillips*
 
 
-Please check [5-0-stable](https://github.com/rails/rails/blob/5-0-stable/activerecord/CHANGELOG.md) for previous changes.
+Please check [5-1-stable](https://github.com/rails/rails/blob/5-1-stable/activerecord/CHANGELOG.md) for previous changes.
diff --git a/activerecord/MIT-LICENSE b/activerecord/MIT-LICENSE
index 1f496cf280..cce00cbc3a 100644
--- a/activerecord/MIT-LICENSE
+++ b/activerecord/MIT-LICENSE
@@ -1,4 +1,4 @@
-Copyright (c) 2004-2016 David Heinemeier Hansson
+Copyright (c) 2004-2018 David Heinemeier Hansson
 
 Permission is hereby granted, free of charge, to any person obtaining
 a copy of this software and associated documentation files (the
diff --git a/activerecord/README.rdoc b/activerecord/README.rdoc
index cfbee4d6f7..19650b82ae 100644
--- a/activerecord/README.rdoc
+++ b/activerecord/README.rdoc
@@ -26,7 +26,7 @@ The Product class is automatically mapped to the table named "products",
 which might look like this:
 
    CREATE TABLE products (
-     id int NOT NULL auto_increment,
+     id bigint NOT NULL auto_increment,
      name varchar(255),
      PRIMARY KEY  (id)
    );
@@ -162,7 +162,7 @@ This would also define the following accessors: <tt>Product#name</tt> and
 == Philosophy
 
 Active Record is an implementation of the object-relational mapping (ORM)
-pattern[http://www.martinfowler.com/eaaCatalog/activeRecord.html] by the same
+pattern[https://www.martinfowler.com/eaaCatalog/activeRecord.html] by the same
 name described by Martin Fowler:
 
   "An object that wraps a row in a database table or view,
@@ -199,7 +199,7 @@ Source code can be downloaded as part of the Rails project on GitHub:
 
 Active Record is released under the MIT license:
 
-* http://www.opensource.org/licenses/MIT
+* https://opensource.org/licenses/MIT
 
 
 == Support
@@ -208,7 +208,7 @@ API documentation is at:
 
 * http://api.rubyonrails.org
 
-Bug reports can be filed for the Ruby on Rails project here:
+Bug reports for the Ruby on Rails project can be filed here:
 
 * https://github.com/rails/rails/issues
 
diff --git a/activerecord/RUNNING_UNIT_TESTS.rdoc b/activerecord/RUNNING_UNIT_TESTS.rdoc
index cd22f76d01..60561e2c0f 100644
--- a/activerecord/RUNNING_UNIT_TESTS.rdoc
+++ b/activerecord/RUNNING_UNIT_TESTS.rdoc
@@ -43,5 +43,9 @@ You can override the +connections:+ parameter in either file using the +ARCONN+
 
   $ ARCONN=postgresql bundle exec ruby -Itest test/cases/base_test.rb
 
+Or
+
+  $ bundle exec rake test:postgresql TEST=test/cases/base_test.rb
+
 You can specify a custom location for the config file using the +ARCONFIG+
 environment variable.
diff --git a/activerecord/Rakefile b/activerecord/Rakefile
index 012db35765..591c451da5 100644
--- a/activerecord/Rakefile
+++ b/activerecord/Rakefile
@@ -1,7 +1,9 @@
-require 'rake/testtask'
+# frozen_string_literal: true
 
-require File.expand_path(File.dirname(__FILE__)) + "/test/config"
-require File.expand_path(File.dirname(__FILE__)) + "/test/support/config"
+require "rake/testtask"
+
+require_relative "test/config"
+require_relative "test/support/config"
 
 def run_without_aborting(*tasks)
   errors = []
@@ -17,12 +19,12 @@ def run_without_aborting(*tasks)
   abort "Errors running #{errors.join(', ')}" if errors.any?
 end
 
-desc 'Run mysql2, sqlite, and postgresql tests by default'
-task :default => :test
+desc "Run mysql2, sqlite, and postgresql tests by default"
+task default: :test
 
 task :package
 
-desc 'Run mysql2, sqlite, and postgresql tests'
+desc "Run mysql2, sqlite, and postgresql tests"
 task :test do
   tasks = defined?(JRUBY_VERSION) ?
     %w(test_jdbcmysql test_jdbcsqlite3 test_jdbcpostgresql) :
@@ -39,19 +41,19 @@ namespace :test do
   end
 end
 
-desc 'Build MySQL and PostgreSQL test databases'
+desc "Build MySQL and PostgreSQL test databases"
 namespace :db do
-  task :create => ['db:mysql:build', 'db:postgresql:build']
-  task :drop => ['db:mysql:drop', 'db:postgresql:drop']
+  task create: ["db:mysql:build", "db:postgresql:build"]
+  task drop: ["db:mysql:drop", "db:postgresql:drop"]
 end
 
 %w( mysql2 postgresql sqlite3 sqlite3_mem db2 oracle jdbcmysql jdbcpostgresql jdbcsqlite3 jdbcderby jdbch2 jdbchsqldb ).each do |adapter|
   namespace :test do
     Rake::TestTask.new(adapter => "#{adapter}:env") { |t|
-      adapter_short = adapter == 'db2' ? adapter : adapter[/^[a-z0-9]+/]
-      t.libs << 'test'
-      t.test_files = (Dir.glob( "test/cases/**/*_test.rb" ).reject {
-        |x| x =~ /\/adapters\//
+      adapter_short = adapter == "db2" ? adapter : adapter[/^[a-z0-9]+/]
+      t.libs << "test"
+      t.test_files = (Dir.glob("test/cases/**/*_test.rb").reject {
+        |x| x.include?("/adapters/")
       } + Dir.glob("test/cases/adapters/#{adapter_short}/**/*_test.rb"))
 
       t.warning = true
@@ -61,23 +63,23 @@ end
 
     namespace :isolated do
       task adapter => "#{adapter}:env" do
-        adapter_short = adapter == 'db2' ? adapter : adapter[/^[a-z0-9]+/]
+        adapter_short = adapter == "db2" ? adapter : adapter[/^[a-z0-9]+/]
         puts [adapter, adapter_short].inspect
         (Dir["test/cases/**/*_test.rb"].reject {
-          |x| x =~ /\/adapters\//
+          |x| x.include?("/adapters/")
         } + Dir["test/cases/adapters/#{adapter_short}/**/*_test.rb"]).all? do |file|
-          sh(Gem.ruby, '-w' ,"-Itest", file)
-        end or raise "Failures"
+          sh(Gem.ruby, "-w", "-Itest", file)
+        end || raise("Failures")
       end
     end
   end
 
   namespace adapter do
-    task :test => "test_#{adapter}"
-    task :isolated_test => "isolated_test_#{adapter}"
+    task test: "test_#{adapter}"
+    task isolated_test: "isolated_test_#{adapter}"
 
     # Set the connection environment for the adapter
-    task(:env) { ENV['ARCONN'] = adapter }
+    task(:env) { ENV["ARCONN"] = adapter }
   end
 
   # Make sure the adapter test evaluates the env setting task
@@ -87,59 +89,54 @@ end
 
 namespace :db do
   namespace :mysql do
-    desc 'Build the MySQL test databases'
+    desc "Build the MySQL test databases"
     task :build do
-      config = ARTest.config['connections']['mysql2']
-      %x( mysql --user=#{config['arunit']['username']} --password=#{config['arunit']['password']} -e "create DATABASE #{config['arunit']['database']} DEFAULT CHARACTER SET utf8 DEFAULT COLLATE utf8_unicode_ci ")
-      %x( mysql --user=#{config['arunit2']['username']} --password=#{config['arunit2']['password']} -e "create DATABASE #{config['arunit2']['database']} DEFAULT CHARACTER SET utf8 DEFAULT COLLATE utf8_unicode_ci ")
+      config = ARTest.config["connections"]["mysql2"]
+      %x( mysql --user=#{config["arunit"]["username"]} --password=#{config["arunit"]["password"]} -e "create DATABASE #{config["arunit"]["database"]} DEFAULT CHARACTER SET utf8 DEFAULT COLLATE utf8_unicode_ci ")
+      %x( mysql --user=#{config["arunit2"]["username"]} --password=#{config["arunit2"]["password"]} -e "create DATABASE #{config["arunit2"]["database"]} DEFAULT CHARACTER SET utf8 DEFAULT COLLATE utf8_unicode_ci ")
     end
 
-    desc 'Drop the MySQL test databases'
+    desc "Drop the MySQL test databases"
     task :drop do
-      config = ARTest.config['connections']['mysql2']
-      %x( mysqladmin --user=#{config['arunit']['username']} --password=#{config['arunit']['password']} -f drop #{config['arunit']['database']} )
-      %x( mysqladmin --user=#{config['arunit2']['username']} --password=#{config['arunit2']['password']} -f drop #{config['arunit2']['database']} )
+      config = ARTest.config["connections"]["mysql2"]
+      %x( mysqladmin --user=#{config["arunit"]["username"]} --password=#{config["arunit"]["password"]} -f drop #{config["arunit"]["database"]} )
+      %x( mysqladmin --user=#{config["arunit2"]["username"]} --password=#{config["arunit2"]["password"]} -f drop #{config["arunit2"]["database"]} )
     end
 
-    desc 'Rebuild the MySQL test databases'
-    task :rebuild => [:drop, :build]
+    desc "Rebuild the MySQL test databases"
+    task rebuild: [:drop, :build]
   end
 
   namespace :postgresql do
-    desc 'Build the PostgreSQL test databases'
+    desc "Build the PostgreSQL test databases"
     task :build do
-      config = ARTest.config['connections']['postgresql']
-      %x( createdb -E UTF8 -T template0 #{config['arunit']['database']} )
-      %x( createdb -E UTF8 -T template0 #{config['arunit2']['database']} )
-
-      # prepare hstore
-      if %x( createdb --version ).strip.gsub(/(.*)(\d\.\d\.\d)$/, "\\2") < "9.1.0"
-        puts "Please prepare hstore data type. See http://www.postgresql.org/docs/current/static/hstore.html"
-      end
+      config = ARTest.config["connections"]["postgresql"]
+      %x( createdb -E UTF8 -T template0 #{config["arunit"]["database"]} )
+      %x( createdb -E UTF8 -T template0 #{config["arunit2"]["database"]} )
     end
 
-    desc 'Drop the PostgreSQL test databases'
+    desc "Drop the PostgreSQL test databases"
     task :drop do
-      config = ARTest.config['connections']['postgresql']
-      %x( dropdb #{config['arunit']['database']} )
-      %x( dropdb #{config['arunit2']['database']} )
+      config = ARTest.config["connections"]["postgresql"]
+      %x( dropdb #{config["arunit"]["database"]} )
+      %x( dropdb #{config["arunit2"]["database"]} )
     end
 
-    desc 'Rebuild the PostgreSQL test databases'
-    task :rebuild => [:drop, :build]
+    desc "Rebuild the PostgreSQL test databases"
+    task rebuild: [:drop, :build]
   end
 end
 
-task :build_mysql_databases => 'db:mysql:build'
-task :drop_mysql_databases => 'db:mysql:drop'
-task :rebuild_mysql_databases => 'db:mysql:rebuild'
+task build_mysql_databases: "db:mysql:build"
+task drop_mysql_databases: "db:mysql:drop"
+task rebuild_mysql_databases: "db:mysql:rebuild"
 
-task :build_postgresql_databases => 'db:postgresql:build'
-task :drop_postgresql_databases => 'db:postgresql:drop'
-task :rebuild_postgresql_databases => 'db:postgresql:rebuild'
+task build_postgresql_databases: "db:postgresql:build"
+task drop_postgresql_databases: "db:postgresql:drop"
+task rebuild_postgresql_databases: "db:postgresql:rebuild"
 
 task :lines do
-  load File.expand_path('..', File.dirname(__FILE__)) + '/tools/line_statistics'
+  load File.expand_path("../tools/line_statistics", __dir__)
   files = FileList["lib/active_record/**/*.rb"]
   CodeTools::LineStatistics.new(files).print_loc
 end
diff --git a/activerecord/activerecord.gemspec b/activerecord/activerecord.gemspec
index 881dee13e4..8e42a11df4 100644
--- a/activerecord/activerecord.gemspec
+++ b/activerecord/activerecord.gemspec
@@ -1,28 +1,35 @@
-version = File.read(File.expand_path('../../RAILS_VERSION', __FILE__)).strip
+# frozen_string_literal: true
+
+version = File.read(File.expand_path("../RAILS_VERSION", __dir__)).strip
 
 Gem::Specification.new do |s|
   s.platform    = Gem::Platform::RUBY
-  s.name        = 'activerecord'
+  s.name        = "activerecord"
   s.version     = version
-  s.summary     = 'Object-relational mapper framework (part of Rails).'
-  s.description = 'Databases on Rails. Build a persistent domain model by mapping database tables to Ruby classes. Strong conventions for associations, validations, aggregations, migrations, and testing come baked-in.'
+  s.summary     = "Object-relational mapper framework (part of Rails)."
+  s.description = "Databases on Rails. Build a persistent domain model by mapping database tables to Ruby classes. Strong conventions for associations, validations, aggregations, migrations, and testing come baked-in."
 
-  s.required_ruby_version = '>= 2.2.2'
+  s.required_ruby_version = ">= 2.2.2"
 
-  s.license = 'MIT'
+  s.license = "MIT"
 
-  s.author   = 'David Heinemeier Hansson'
-  s.email    = 'david@loudthinking.com'
-  s.homepage = 'http://rubyonrails.org'
+  s.author   = "David Heinemeier Hansson"
+  s.email    = "david@loudthinking.com"
+  s.homepage = "http://rubyonrails.org"
 
-  s.files        = Dir['CHANGELOG.md', 'MIT-LICENSE', 'README.rdoc', 'examples/**/*', 'lib/**/*']
-  s.require_path = 'lib'
+  s.files        = Dir["CHANGELOG.md", "MIT-LICENSE", "README.rdoc", "examples/**/*", "lib/**/*"]
+  s.require_path = "lib"
 
   s.extra_rdoc_files = %w(README.rdoc)
-  s.rdoc_options.concat ['--main',  'README.rdoc']
+  s.rdoc_options.concat ["--main",  "README.rdoc"]
+
+  s.metadata = {
+    "source_code_uri" => "https://github.com/rails/rails/tree/v#{version}/activerecord",
+    "changelog_uri"   => "https://github.com/rails/rails/blob/v#{version}/activerecord/CHANGELOG.md"
+  }
 
-  s.add_dependency 'activesupport', version
-  s.add_dependency 'activemodel',   version
+  s.add_dependency "activesupport", version
+  s.add_dependency "activemodel",   version
 
-  s.add_dependency 'arel', '~> 7.0'
+  s.add_dependency "arel", ">= 9.0"
 end
diff --git a/activerecord/bin/test b/activerecord/bin/test
index 7417b068bf..83c192531e 100755
--- a/activerecord/bin/test
+++ b/activerecord/bin/test
@@ -1,6 +1,9 @@
 #!/usr/bin/env ruby
-COMPONENT_ROOT = File.expand_path("../../", __FILE__)
-require File.expand_path("../tools/test", COMPONENT_ROOT)
+# frozen_string_literal: true
+
+COMPONENT_ROOT = File.expand_path("..", __dir__)
+require_relative "../../tools/test"
+
 module Minitest
   def self.plugin_active_record_options(opts, options)
     opts.separator ""
@@ -14,6 +17,4 @@ module Minitest
   end
 end
 
-Minitest.extensions.unshift 'active_record'
-
-exit Minitest.run(ARGV)
+Minitest.extensions.unshift "active_record"
diff --git a/activerecord/examples/performance.rb b/activerecord/examples/performance.rb
index c3c46c19c5..1a2c78f39b 100644
--- a/activerecord/examples/performance.rb
+++ b/activerecord/examples/performance.rb
@@ -1,10 +1,12 @@
+# frozen_string_literal: true
+
 require "active_record"
-require 'benchmark/ips'
+require "benchmark/ips"
 
-TIME    = (ENV['BENCHMARK_TIME'] || 20).to_i
-RECORDS = (ENV['BENCHMARK_RECORDS'] || TIME*1000).to_i
+TIME    = (ENV["BENCHMARK_TIME"] || 20).to_i
+RECORDS = (ENV["BENCHMARK_RECORDS"] || TIME * 1000).to_i
 
-conn = { adapter: 'sqlite3', database: ':memory:' }
+conn = { adapter: "sqlite3", database: ":memory:" }
 
 ActiveRecord::Base.establish_connection(conn)
 
@@ -42,26 +44,26 @@ class Exhibit < ActiveRecord::Base
   def self.feel(exhibits) exhibits.each(&:feel) end
 end
 
-def progress_bar(int); print "." if (int%100).zero? ; end
+def progress_bar(int); print "." if (int % 100).zero? ; end
 
-puts 'Generating data...'
+puts "Generating data..."
 
 module ActiveRecord
   class Faker
-    LOREM = %Q{Lorem ipsum dolor sit amet, consectetur adipiscing elit. Suspendisse non aliquet diam. Curabitur vel urna metus, quis malesuada elit.
+    LOREM = "Lorem ipsum dolor sit amet, consectetur adipiscing elit. Suspendisse non aliquet diam. Curabitur vel urna metus, quis malesuada elit.
      Integer consequat tincidunt felis. Etiam non erat dolor. Vivamus imperdiet nibh sit amet diam eleifend id posuere diam malesuada. Mauris at accumsan sem.
      Donec id lorem neque. Fusce erat lorem, ornare eu congue vitae, malesuada quis neque. Maecenas vel urna a velit pretium fermentum. Donec tortor enim,
      tempor venenatis egestas a, tempor sed ipsum. Ut arcu justo, faucibus non imperdiet ac, interdum at diam. Pellentesque ipsum enim, venenatis ut iaculis vitae,
      varius vitae sem. Sed rutrum quam ac elit euismod bibendum. Donec ultricies ultricies magna, at lacinia libero mollis aliquam. Sed ac arcu in tortor elementum
      tincidunt vel interdum sem. Curabitur eget erat arcu. Praesent eget eros leo. Nam magna enim, sollicitudin vehicula scelerisque in, vulputate ut libero.
-     Praesent varius tincidunt commodo}.split
+     Praesent varius tincidunt commodo".split
 
     def self.name
-      LOREM.grep(/^\w*$/).sort_by { rand }.first(2).join ' '
+      LOREM.grep(/^\w*$/).sort_by { rand }.first(2).join " "
     end
 
     def self.email
-      LOREM.grep(/^\w*$/).sort_by { rand }.first(2).join('@') + ".com"
+      LOREM.grep(/^\w*$/).sort_by { rand }.first(2).join("@") + ".com"
     end
   end
 end
@@ -72,7 +74,7 @@ end
 
 # Using the same paragraph for all exhibits because it is very slow
 # to generate unique paragraphs for all exhibits.
-notes = ActiveRecord::Faker::LOREM.join ' '
+notes = ActiveRecord::Faker::LOREM.join " "
 today = Date.today
 
 puts "Inserting #{RECORDS} users and exhibits..."
@@ -95,9 +97,9 @@ puts "Done!\n"
 
 Benchmark.ips(TIME) do |x|
   ar_obj       = Exhibit.find(1)
-  attrs        = { name: 'sam' }
-  attrs_first  = { name: 'sam' }
-  attrs_second = { name: 'tom' }
+  attrs        = { name: "sam" }
+  attrs_first  = { name: "sam" }
+  attrs_second = { name: "tom" }
   exhibit      = {
     name: ActiveRecord::Faker.name,
     notes: notes,
@@ -108,22 +110,22 @@ Benchmark.ips(TIME) do |x|
     ar_obj.id
   end
 
-  x.report 'Model.new (instantiation)' do
+  x.report "Model.new (instantiation)" do
     Exhibit.new
   end
 
-  x.report 'Model.new (setting attributes)' do
+  x.report "Model.new (setting attributes)" do
     Exhibit.new(attrs)
   end
 
-  x.report 'Model.first' do
+  x.report "Model.first" do
     Exhibit.first.look
   end
 
-  x.report 'Model.take' do 
+  x.report "Model.take" do
     Exhibit.take
   end
-  
+
   x.report("Model.all limit(100)") do
     Exhibit.look Exhibit.limit(100)
   end
@@ -140,36 +142,36 @@ Benchmark.ips(TIME) do |x|
     Exhibit.look Exhibit.limit(10000)
   end
 
-  x.report 'Model.named_scope' do
+  x.report "Model.named_scope" do
     Exhibit.limit(10).with_name.with_notes
   end
 
-  x.report 'Model.create' do
+  x.report "Model.create" do
     Exhibit.create(exhibit)
   end
 
-  x.report 'Resource#attributes=' do
+  x.report "Resource#attributes=" do
     e = Exhibit.new(attrs_first)
     e.attributes = attrs_second
   end
 
-  x.report 'Resource#update' do
-    Exhibit.first.update(name: 'bob')
+  x.report "Resource#update" do
+    Exhibit.first.update(name: "bob")
   end
 
-  x.report 'Resource#destroy' do
+  x.report "Resource#destroy" do
     Exhibit.first.destroy
   end
 
-  x.report 'Model.transaction' do
+  x.report "Model.transaction" do
     Exhibit.transaction { Exhibit.new }
   end
 
-  x.report 'Model.find(id)' do
+  x.report "Model.find(id)" do
     User.find(1)
   end
 
-  x.report 'Model.find_by_sql' do
+  x.report "Model.find_by_sql" do
     Exhibit.find_by_sql("SELECT * FROM exhibits WHERE id = #{(rand * 1000 + 1).to_i}").first
   end
 
diff --git a/activerecord/examples/simple.rb b/activerecord/examples/simple.rb
index 5a041e8417..280b786d73 100644
--- a/activerecord/examples/simple.rb
+++ b/activerecord/examples/simple.rb
@@ -1,13 +1,15 @@
-require 'active_record'
+# frozen_string_literal: true
+
+require "active_record"
 
 class Person < ActiveRecord::Base
-  establish_connection adapter: 'sqlite3', database: 'foobar.db'
+  establish_connection adapter: "sqlite3", database: "foobar.db"
   connection.create_table table_name, force: true do |t|
     t.string :name
   end
 end
 
-bob = Person.create!(name: 'bob')
+bob = Person.create!(name: "bob")
 puts Person.all.inspect
 bob.destroy
 puts Person.all.inspect
diff --git a/activerecord/lib/active_record.rb b/activerecord/lib/active_record.rb
index baa497dc98..b4377ad6be 100644
--- a/activerecord/lib/active_record.rb
+++ b/activerecord/lib/active_record.rb
@@ -1,5 +1,7 @@
+# frozen_string_literal: true
+
 #--
-# Copyright (c) 2004-2016 David Heinemeier Hansson
+# Copyright (c) 2004-2018 David Heinemeier Hansson
 #
 # Permission is hereby granted, free of charge, to any person obtaining
 # a copy of this software and associated documentation files (the
@@ -21,18 +23,18 @@
 # WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 #++
 
-require 'active_support'
-require 'active_support/rails'
-require 'active_model'
-require 'arel'
+require "active_support"
+require "active_support/rails"
+require "active_model"
+require "arel"
+require "yaml"
 
-require 'active_record/version'
-require 'active_record/attribute_set'
+require "active_record/version"
+require "active_model/attribute_set"
 
 module ActiveRecord
   extend ActiveSupport::Autoload
 
-  autoload :Attribute
   autoload :Base
   autoload :Callbacks
   autoload :Core
@@ -44,9 +46,8 @@ module ActiveRecord
   autoload :Explain
   autoload :Inheritance
   autoload :Integration
-  autoload :LegacyYamlAdapter
   autoload :Migration
-  autoload :Migrator, 'active_record/migration'
+  autoload :Migrator, "active_record/migration"
   autoload :ModelSchema
   autoload :NestedAttributes
   autoload :NoTouching
@@ -56,7 +57,7 @@ module ActiveRecord
   autoload :Querying
   autoload :CollectionCacheKey
   autoload :ReadonlyAttributes
-  autoload :RecordInvalid, 'active_record/validations'
+  autoload :RecordInvalid, "active_record/validations"
   autoload :Reflection
   autoload :RuntimeRegistry
   autoload :Sanitization
@@ -68,7 +69,6 @@ module ActiveRecord
   autoload :StatementCache
   autoload :Store
   autoload :Suppressor
-  autoload :TableMetadata
   autoload :Timestamp
   autoload :Transactions
   autoload :Translation
@@ -76,9 +76,9 @@ module ActiveRecord
   autoload :SecureToken
 
   eager_autoload do
-    autoload :ActiveRecordError, 'active_record/errors'
-    autoload :ConnectionNotEstablished, 'active_record/errors'
-    autoload :ConnectionAdapters, 'active_record/connection_adapters/abstract_adapter'
+    autoload :ActiveRecordError, "active_record/errors"
+    autoload :ConnectionNotEstablished, "active_record/errors"
+    autoload :ConnectionAdapters, "active_record/connection_adapters/abstract_adapter"
 
     autoload :Aggregations
     autoload :Associations
@@ -86,11 +86,13 @@ module ActiveRecord
     autoload :AttributeMethods
     autoload :AutosaveAssociation
 
+    autoload :LegacyYamlAdapter
+
     autoload :Relation
     autoload :AssociationRelation
     autoload :NullRelation
 
-    autoload_under 'relation' do
+    autoload_under "relation" do
       autoload :QueryMethods
       autoload :FinderMethods
       autoload :Calculations
@@ -101,11 +103,13 @@ module ActiveRecord
     end
 
     autoload :Result
+    autoload :TableMetadata
+    autoload :Type
   end
 
   module Coders
-    autoload :YAMLColumn, 'active_record/coders/yaml_column'
-    autoload :JSON, 'active_record/coders/json'
+    autoload :YAMLColumn, "active_record/coders/yaml_column"
+    autoload :JSON, "active_record/coders/json"
   end
 
   module AttributeMethods
@@ -153,13 +157,13 @@ module ActiveRecord
     extend ActiveSupport::Autoload
 
     autoload :DatabaseTasks
-    autoload :SQLiteDatabaseTasks, 'active_record/tasks/sqlite_database_tasks'
-    autoload :MySQLDatabaseTasks,  'active_record/tasks/mysql_database_tasks'
+    autoload :SQLiteDatabaseTasks, "active_record/tasks/sqlite_database_tasks"
+    autoload :MySQLDatabaseTasks,  "active_record/tasks/mysql_database_tasks"
     autoload :PostgreSQLDatabaseTasks,
-      'active_record/tasks/postgresql_database_tasks'
+      "active_record/tasks/postgresql_database_tasks"
   end
 
-  autoload :TestFixtures, 'active_record/fixtures'
+  autoload :TestFixtures, "active_record/fixtures"
 
   def self.eager_load!
     super
@@ -176,5 +180,9 @@ ActiveSupport.on_load(:active_record) do
 end
 
 ActiveSupport.on_load(:i18n) do
-  I18n.load_path << File.dirname(__FILE__) + '/active_record/locale/en.yml'
+  I18n.load_path << File.expand_path("active_record/locale/en.yml", __dir__)
 end
+
+YAML.load_tags["!ruby/object:ActiveRecord::AttributeSet"] = "ActiveModel::AttributeSet"
+YAML.load_tags["!ruby/object:ActiveRecord::Attribute::FromDatabase"] = "ActiveModel::Attribute::FromDatabase"
+YAML.load_tags["!ruby/object:ActiveRecord::LazyAttributeHash"] = "ActiveModel::LazyAttributeHash"
diff --git a/activerecord/lib/active_record/aggregations.rb b/activerecord/lib/active_record/aggregations.rb
index 8bed5bca28..e5e89734d2 100644
--- a/activerecord/lib/active_record/aggregations.rb
+++ b/activerecord/lib/active_record/aggregations.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActiveRecord
   # See ActiveRecord::Aggregations::ClassMethods for documentation
   module Aggregations
@@ -15,266 +17,268 @@ module ActiveRecord
 
     private
 
-      def clear_aggregation_cache # :nodoc:
+      def clear_aggregation_cache
         @aggregation_cache.clear if persisted?
       end
 
-      def init_internals # :nodoc:
+      def init_internals
         @aggregation_cache = {}
         super
       end
 
-    # Active Record implements aggregation through a macro-like class method called #composed_of
-    # for representing attributes as value objects. It expresses relationships like "Account [is]
-    # composed of Money [among other things]" or "Person [is] composed of [an] address". Each call
-    # to the macro adds a description of how the value objects are created from the attributes of
-    # the entity object (when the entity is initialized either as a new object or from finding an
-    # existing object) and how it can be turned back into attributes (when the entity is saved to
-    # the database).
-    #
-    #   class Customer < ActiveRecord::Base
-    #     composed_of :balance, class_name: "Money", mapping: %w(amount currency)
-    #     composed_of :address, mapping: [ %w(address_street street), %w(address_city city) ]
-    #   end
-    #
-    # The customer class now has the following methods to manipulate the value objects:
-    # * <tt>Customer#balance, Customer#balance=(money)</tt>
-    # * <tt>Customer#address, Customer#address=(address)</tt>
-    #
-    # These methods will operate with value objects like the ones described below:
-    #
-    #  class Money
-    #    include Comparable
-    #    attr_reader :amount, :currency
-    #    EXCHANGE_RATES = { "USD_TO_DKK" => 6 }
-    #
-    #    def initialize(amount, currency = "USD")
-    #      @amount, @currency = amount, currency
-    #    end
-    #
-    #    def exchange_to(other_currency)
-    #      exchanged_amount = (amount * EXCHANGE_RATES["#{currency}_TO_#{other_currency}"]).floor
-    #      Money.new(exchanged_amount, other_currency)
-    #    end
-    #
-    #    def ==(other_money)
-    #      amount == other_money.amount && currency == other_money.currency
-    #    end
-    #
-    #    def <=>(other_money)
-    #      if currency == other_money.currency
-    #        amount <=> other_money.amount
-    #      else
-    #        amount <=> other_money.exchange_to(currency).amount
-    #      end
-    #    end
-    #  end
-    #
-    #  class Address
-    #    attr_reader :street, :city
-    #    def initialize(street, city)
-    #      @street, @city = street, city
-    #    end
-    #
-    #    def close_to?(other_address)
-    #      city == other_address.city
-    #    end
-    #
-    #    def ==(other_address)
-    #      city == other_address.city && street == other_address.street
-    #    end
-    #  end
-    #
-    # Now it's possible to access attributes from the database through the value objects instead. If
-    # you choose to name the composition the same as the attribute's name, it will be the only way to
-    # access that attribute. That's the case with our +balance+ attribute. You interact with the value
-    # objects just like you would with any other attribute:
-    #
-    #   customer.balance = Money.new(20)     # sets the Money value object and the attribute
-    #   customer.balance                     # => Money value object
-    #   customer.balance.exchange_to("DKK")  # => Money.new(120, "DKK")
-    #   customer.balance > Money.new(10)     # => true
-    #   customer.balance == Money.new(20)    # => true
-    #   customer.balance < Money.new(5)      # => false
-    #
-    # Value objects can also be composed of multiple attributes, such as the case of Address. The order
-    # of the mappings will determine the order of the parameters.
-    #
-    #   customer.address_street = "Hyancintvej"
-    #   customer.address_city   = "Copenhagen"
-    #   customer.address        # => Address.new("Hyancintvej", "Copenhagen")
-    #
-    #   customer.address = Address.new("May Street", "Chicago")
-    #   customer.address_street # => "May Street"
-    #   customer.address_city   # => "Chicago"
-    #
-    # == Writing value objects
-    #
-    # Value objects are immutable and interchangeable objects that represent a given value, such as
-    # a Money object representing $5. Two Money objects both representing $5 should be equal (through
-    # methods such as <tt>==</tt> and <tt><=></tt> from Comparable if ranking makes sense). This is
-    # unlike entity objects where equality is determined by identity. An entity class such as Customer can
-    # easily have two different objects that both have an address on Hyancintvej. Entity identity is
-    # determined by object or relational unique identifiers (such as primary keys). Normal
-    # ActiveRecord::Base classes are entity objects.
-    #
-    # It's also important to treat the value objects as immutable. Don't allow the Money object to have
-    # its amount changed after creation. Create a new Money object with the new value instead. The
-    # <tt>Money#exchange_to</tt> method is an example of this. It returns a new value object instead of changing
-    # its own values. Active Record won't persist value objects that have been changed through means
-    # other than the writer method.
-    #
-    # The immutable requirement is enforced by Active Record by freezing any object assigned as a value
-    # object. Attempting to change it afterwards will result in a +RuntimeError+.
-    #
-    # Read more about value objects on http://c2.com/cgi/wiki?ValueObject and on the dangers of not
-    # keeping value objects immutable on http://c2.com/cgi/wiki?ValueObjectsShouldBeImmutable
-    #
-    # == Custom constructors and converters
-    #
-    # By default value objects are initialized by calling the <tt>new</tt> constructor of the value
-    # class passing each of the mapped attributes, in the order specified by the <tt>:mapping</tt>
-    # option, as arguments. If the value class doesn't support this convention then #composed_of allows
-    # a custom constructor to be specified.
-    #
-    # When a new value is assigned to the value object, the default assumption is that the new value
-    # is an instance of the value class. Specifying a custom converter allows the new value to be automatically
-    # converted to an instance of value class if necessary.
-    #
-    # For example, the +NetworkResource+ model has +network_address+ and +cidr_range+ attributes that should be
-    # aggregated using the +NetAddr::CIDR+ value class (http://www.rubydoc.info/gems/netaddr/1.5.0/NetAddr/CIDR).
-    # The constructor for the value class is called +create+ and it expects a CIDR address string as a parameter.
-    # New values can be assigned to the value object using either another +NetAddr::CIDR+ object, a string
-    # or an array. The <tt>:constructor</tt> and <tt>:converter</tt> options can be used to meet
-    # these requirements:
-    #
-    #   class NetworkResource < ActiveRecord::Base
-    #     composed_of :cidr,
-    #                 class_name: 'NetAddr::CIDR',
-    #                 mapping: [ %w(network_address network), %w(cidr_range bits) ],
-    #                 allow_nil: true,
-    #                 constructor: Proc.new { |network_address, cidr_range| NetAddr::CIDR.create("#{network_address}/#{cidr_range}") },
-    #                 converter: Proc.new { |value| NetAddr::CIDR.create(value.is_a?(Array) ? value.join('/') : value) }
-    #   end
-    #
-    #   # This calls the :constructor
-    #   network_resource = NetworkResource.new(network_address: '192.168.0.1', cidr_range: 24)
-    #
-    #   # These assignments will both use the :converter
-    #   network_resource.cidr = [ '192.168.2.1', 8 ]
-    #   network_resource.cidr = '192.168.0.1/24'
-    #
-    #   # This assignment won't use the :converter as the value is already an instance of the value class
-    #   network_resource.cidr = NetAddr::CIDR.create('192.168.2.1/8')
-    #
-    #   # Saving and then reloading will use the :constructor on reload
-    #   network_resource.save
-    #   network_resource.reload
-    #
-    # == Finding records by a value object
-    #
-    # Once a #composed_of relationship is specified for a model, records can be loaded from the database
-    # by specifying an instance of the value object in the conditions hash. The following example
-    # finds all customers with +balance_amount+ equal to 20 and +balance_currency+ equal to "USD":
-    #
-    #   Customer.where(balance: Money.new(20, "USD"))
-    #
-    module ClassMethods
-      # Adds reader and writer methods for manipulating a value object:
-      # <tt>composed_of :address</tt> adds <tt>address</tt> and <tt>address=(new_address)</tt> methods.
-      #
-      # Options are:
-      # * <tt>:class_name</tt> - Specifies the class name of the association. Use it only if that name
-      #   can't be inferred from the part id. So <tt>composed_of :address</tt> will by default be linked
-      #   to the Address class, but if the real class name is +CompanyAddress+, you'll have to specify it
-      #   with this option.
-      # * <tt>:mapping</tt> - Specifies the mapping of entity attributes to attributes of the value
-      #   object. Each mapping is represented as an array where the first item is the name of the
-      #   entity attribute and the second item is the name of the attribute in the value object. The
-      #   order in which mappings are defined determines the order in which attributes are sent to the
-      #   value class constructor.
-      # * <tt>:allow_nil</tt> - Specifies that the value object will not be instantiated when all mapped
-      #   attributes are +nil+. Setting the value object to +nil+ has the effect of writing +nil+ to all
-      #   mapped attributes.
-      #   This defaults to +false+.
-      # * <tt>:constructor</tt> - A symbol specifying the name of the constructor method or a Proc that
-      #   is called to initialize the value object. The constructor is passed all of the mapped attributes,
-      #   in the order that they are defined in the <tt>:mapping option</tt>, as arguments and uses them
-      #   to instantiate a <tt>:class_name</tt> object.
-      #   The default is <tt>:new</tt>.
-      # * <tt>:converter</tt> - A symbol specifying the name of a class method of <tt>:class_name</tt>
-      #   or a Proc that is called when a new value is assigned to the value object. The converter is
-      #   passed the single value that is used in the assignment and is only called if the new value is
-      #   not an instance of <tt>:class_name</tt>. If <tt>:allow_nil</tt> is set to true, the converter
-      #   can return nil to skip the assignment.
-      #
-      # Option examples:
-      #   composed_of :temperature, mapping: %w(reading celsius)
-      #   composed_of :balance, class_name: "Money", mapping: %w(balance amount),
-      #                         converter: Proc.new { |balance| balance.to_money }
-      #   composed_of :address, mapping: [ %w(address_street street), %w(address_city city) ]
-      #   composed_of :gps_location
-      #   composed_of :gps_location, allow_nil: true
-      #   composed_of :ip_address,
-      #               class_name: 'IPAddr',
-      #               mapping: %w(ip to_i),
-      #               constructor: Proc.new { |ip| IPAddr.new(ip, Socket::AF_INET) },
-      #               converter: Proc.new { |ip| ip.is_a?(Integer) ? IPAddr.new(ip, Socket::AF_INET) : IPAddr.new(ip.to_s) }
-      #
-      def composed_of(part_id, options = {})
-        options.assert_valid_keys(:class_name, :mapping, :allow_nil, :constructor, :converter)
+      # Active Record implements aggregation through a macro-like class method called #composed_of
+      # for representing attributes as value objects. It expresses relationships like "Account [is]
+      # composed of Money [among other things]" or "Person [is] composed of [an] address". Each call
+      # to the macro adds a description of how the value objects are created from the attributes of
+      # the entity object (when the entity is initialized either as a new object or from finding an
+      # existing object) and how it can be turned back into attributes (when the entity is saved to
+      # the database).
+      #
+      #   class Customer < ActiveRecord::Base
+      #     composed_of :balance, class_name: "Money", mapping: %w(amount currency)
+      #     composed_of :address, mapping: [ %w(address_street street), %w(address_city city) ]
+      #   end
+      #
+      # The customer class now has the following methods to manipulate the value objects:
+      # * <tt>Customer#balance, Customer#balance=(money)</tt>
+      # * <tt>Customer#address, Customer#address=(address)</tt>
+      #
+      # These methods will operate with value objects like the ones described below:
+      #
+      #  class Money
+      #    include Comparable
+      #    attr_reader :amount, :currency
+      #    EXCHANGE_RATES = { "USD_TO_DKK" => 6 }
+      #
+      #    def initialize(amount, currency = "USD")
+      #      @amount, @currency = amount, currency
+      #    end
+      #
+      #    def exchange_to(other_currency)
+      #      exchanged_amount = (amount * EXCHANGE_RATES["#{currency}_TO_#{other_currency}"]).floor
+      #      Money.new(exchanged_amount, other_currency)
+      #    end
+      #
+      #    def ==(other_money)
+      #      amount == other_money.amount && currency == other_money.currency
+      #    end
+      #
+      #    def <=>(other_money)
+      #      if currency == other_money.currency
+      #        amount <=> other_money.amount
+      #      else
+      #        amount <=> other_money.exchange_to(currency).amount
+      #      end
+      #    end
+      #  end
+      #
+      #  class Address
+      #    attr_reader :street, :city
+      #    def initialize(street, city)
+      #      @street, @city = street, city
+      #    end
+      #
+      #    def close_to?(other_address)
+      #      city == other_address.city
+      #    end
+      #
+      #    def ==(other_address)
+      #      city == other_address.city && street == other_address.street
+      #    end
+      #  end
+      #
+      # Now it's possible to access attributes from the database through the value objects instead. If
+      # you choose to name the composition the same as the attribute's name, it will be the only way to
+      # access that attribute. That's the case with our +balance+ attribute. You interact with the value
+      # objects just like you would with any other attribute:
+      #
+      #   customer.balance = Money.new(20)     # sets the Money value object and the attribute
+      #   customer.balance                     # => Money value object
+      #   customer.balance.exchange_to("DKK")  # => Money.new(120, "DKK")
+      #   customer.balance > Money.new(10)     # => true
+      #   customer.balance == Money.new(20)    # => true
+      #   customer.balance < Money.new(5)      # => false
+      #
+      # Value objects can also be composed of multiple attributes, such as the case of Address. The order
+      # of the mappings will determine the order of the parameters.
+      #
+      #   customer.address_street = "Hyancintvej"
+      #   customer.address_city   = "Copenhagen"
+      #   customer.address        # => Address.new("Hyancintvej", "Copenhagen")
+      #
+      #   customer.address = Address.new("May Street", "Chicago")
+      #   customer.address_street # => "May Street"
+      #   customer.address_city   # => "Chicago"
+      #
+      # == Writing value objects
+      #
+      # Value objects are immutable and interchangeable objects that represent a given value, such as
+      # a Money object representing $5. Two Money objects both representing $5 should be equal (through
+      # methods such as <tt>==</tt> and <tt><=></tt> from Comparable if ranking makes sense). This is
+      # unlike entity objects where equality is determined by identity. An entity class such as Customer can
+      # easily have two different objects that both have an address on Hyancintvej. Entity identity is
+      # determined by object or relational unique identifiers (such as primary keys). Normal
+      # ActiveRecord::Base classes are entity objects.
+      #
+      # It's also important to treat the value objects as immutable. Don't allow the Money object to have
+      # its amount changed after creation. Create a new Money object with the new value instead. The
+      # <tt>Money#exchange_to</tt> method is an example of this. It returns a new value object instead of changing
+      # its own values. Active Record won't persist value objects that have been changed through means
+      # other than the writer method.
+      #
+      # The immutable requirement is enforced by Active Record by freezing any object assigned as a value
+      # object. Attempting to change it afterwards will result in a +RuntimeError+.
+      #
+      # Read more about value objects on http://c2.com/cgi/wiki?ValueObject and on the dangers of not
+      # keeping value objects immutable on http://c2.com/cgi/wiki?ValueObjectsShouldBeImmutable
+      #
+      # == Custom constructors and converters
+      #
+      # By default value objects are initialized by calling the <tt>new</tt> constructor of the value
+      # class passing each of the mapped attributes, in the order specified by the <tt>:mapping</tt>
+      # option, as arguments. If the value class doesn't support this convention then #composed_of allows
+      # a custom constructor to be specified.
+      #
+      # When a new value is assigned to the value object, the default assumption is that the new value
+      # is an instance of the value class. Specifying a custom converter allows the new value to be automatically
+      # converted to an instance of value class if necessary.
+      #
+      # For example, the +NetworkResource+ model has +network_address+ and +cidr_range+ attributes that should be
+      # aggregated using the +NetAddr::CIDR+ value class (http://www.rubydoc.info/gems/netaddr/1.5.0/NetAddr/CIDR).
+      # The constructor for the value class is called +create+ and it expects a CIDR address string as a parameter.
+      # New values can be assigned to the value object using either another +NetAddr::CIDR+ object, a string
+      # or an array. The <tt>:constructor</tt> and <tt>:converter</tt> options can be used to meet
+      # these requirements:
+      #
+      #   class NetworkResource < ActiveRecord::Base
+      #     composed_of :cidr,
+      #                 class_name: 'NetAddr::CIDR',
+      #                 mapping: [ %w(network_address network), %w(cidr_range bits) ],
+      #                 allow_nil: true,
+      #                 constructor: Proc.new { |network_address, cidr_range| NetAddr::CIDR.create("#{network_address}/#{cidr_range}") },
+      #                 converter: Proc.new { |value| NetAddr::CIDR.create(value.is_a?(Array) ? value.join('/') : value) }
+      #   end
+      #
+      #   # This calls the :constructor
+      #   network_resource = NetworkResource.new(network_address: '192.168.0.1', cidr_range: 24)
+      #
+      #   # These assignments will both use the :converter
+      #   network_resource.cidr = [ '192.168.2.1', 8 ]
+      #   network_resource.cidr = '192.168.0.1/24'
+      #
+      #   # This assignment won't use the :converter as the value is already an instance of the value class
+      #   network_resource.cidr = NetAddr::CIDR.create('192.168.2.1/8')
+      #
+      #   # Saving and then reloading will use the :constructor on reload
+      #   network_resource.save
+      #   network_resource.reload
+      #
+      # == Finding records by a value object
+      #
+      # Once a #composed_of relationship is specified for a model, records can be loaded from the database
+      # by specifying an instance of the value object in the conditions hash. The following example
+      # finds all customers with +balance_amount+ equal to 20 and +balance_currency+ equal to "USD":
+      #
+      #   Customer.where(balance: Money.new(20, "USD"))
+      #
+      module ClassMethods
+        # Adds reader and writer methods for manipulating a value object:
+        # <tt>composed_of :address</tt> adds <tt>address</tt> and <tt>address=(new_address)</tt> methods.
+        #
+        # Options are:
+        # * <tt>:class_name</tt> - Specifies the class name of the association. Use it only if that name
+        #   can't be inferred from the part id. So <tt>composed_of :address</tt> will by default be linked
+        #   to the Address class, but if the real class name is +CompanyAddress+, you'll have to specify it
+        #   with this option.
+        # * <tt>:mapping</tt> - Specifies the mapping of entity attributes to attributes of the value
+        #   object. Each mapping is represented as an array where the first item is the name of the
+        #   entity attribute and the second item is the name of the attribute in the value object. The
+        #   order in which mappings are defined determines the order in which attributes are sent to the
+        #   value class constructor.
+        # * <tt>:allow_nil</tt> - Specifies that the value object will not be instantiated when all mapped
+        #   attributes are +nil+. Setting the value object to +nil+ has the effect of writing +nil+ to all
+        #   mapped attributes.
+        #   This defaults to +false+.
+        # * <tt>:constructor</tt> - A symbol specifying the name of the constructor method or a Proc that
+        #   is called to initialize the value object. The constructor is passed all of the mapped attributes,
+        #   in the order that they are defined in the <tt>:mapping option</tt>, as arguments and uses them
+        #   to instantiate a <tt>:class_name</tt> object.
+        #   The default is <tt>:new</tt>.
+        # * <tt>:converter</tt> - A symbol specifying the name of a class method of <tt>:class_name</tt>
+        #   or a Proc that is called when a new value is assigned to the value object. The converter is
+        #   passed the single value that is used in the assignment and is only called if the new value is
+        #   not an instance of <tt>:class_name</tt>. If <tt>:allow_nil</tt> is set to true, the converter
+        #   can return +nil+ to skip the assignment.
+        #
+        # Option examples:
+        #   composed_of :temperature, mapping: %w(reading celsius)
+        #   composed_of :balance, class_name: "Money", mapping: %w(balance amount),
+        #                         converter: Proc.new { |balance| balance.to_money }
+        #   composed_of :address, mapping: [ %w(address_street street), %w(address_city city) ]
+        #   composed_of :gps_location
+        #   composed_of :gps_location, allow_nil: true
+        #   composed_of :ip_address,
+        #               class_name: 'IPAddr',
+        #               mapping: %w(ip to_i),
+        #               constructor: Proc.new { |ip| IPAddr.new(ip, Socket::AF_INET) },
+        #               converter: Proc.new { |ip| ip.is_a?(Integer) ? IPAddr.new(ip, Socket::AF_INET) : IPAddr.new(ip.to_s) }
+        #
+        def composed_of(part_id, options = {})
+          options.assert_valid_keys(:class_name, :mapping, :allow_nil, :constructor, :converter)
 
-        name        = part_id.id2name
-        class_name  = options[:class_name]  || name.camelize
-        mapping     = options[:mapping]     || [ name, name ]
-        mapping     = [ mapping ] unless mapping.first.is_a?(Array)
-        allow_nil   = options[:allow_nil]   || false
-        constructor = options[:constructor] || :new
-        converter   = options[:converter]
+          name        = part_id.id2name
+          class_name  = options[:class_name]  || name.camelize
+          mapping     = options[:mapping]     || [ name, name ]
+          mapping     = [ mapping ] unless mapping.first.is_a?(Array)
+          allow_nil   = options[:allow_nil]   || false
+          constructor = options[:constructor] || :new
+          converter   = options[:converter]
 
-        reader_method(name, class_name, mapping, allow_nil, constructor)
-        writer_method(name, class_name, mapping, allow_nil, converter)
+          reader_method(name, class_name, mapping, allow_nil, constructor)
+          writer_method(name, class_name, mapping, allow_nil, converter)
 
-        reflection = ActiveRecord::Reflection.create(:composed_of, part_id, nil, options, self)
-        Reflection.add_aggregate_reflection self, part_id, reflection
-      end
+          reflection = ActiveRecord::Reflection.create(:composed_of, part_id, nil, options, self)
+          Reflection.add_aggregate_reflection self, part_id, reflection
+        end
 
-      private
-        def reader_method(name, class_name, mapping, allow_nil, constructor)
-          define_method(name) do
-            if @aggregation_cache[name].nil? && (!allow_nil || mapping.any? {|key, _| !_read_attribute(key).nil? })
-              attrs = mapping.collect {|key, _| _read_attribute(key)}
-              object = constructor.respond_to?(:call) ?
-                constructor.call(*attrs) :
-                class_name.constantize.send(constructor, *attrs)
-              @aggregation_cache[name] = object
+        private
+          def reader_method(name, class_name, mapping, allow_nil, constructor)
+            define_method(name) do
+              if @aggregation_cache[name].nil? && (!allow_nil || mapping.any? { |key, _| !_read_attribute(key).nil? })
+                attrs = mapping.collect { |key, _| _read_attribute(key) }
+                object = constructor.respond_to?(:call) ?
+                  constructor.call(*attrs) :
+                  class_name.constantize.send(constructor, *attrs)
+                @aggregation_cache[name] = object
+              end
+              @aggregation_cache[name]
             end
-            @aggregation_cache[name]
           end
-        end
 
-        def writer_method(name, class_name, mapping, allow_nil, converter)
-          define_method("#{name}=") do |part|
-            klass = class_name.constantize
+          def writer_method(name, class_name, mapping, allow_nil, converter)
+            define_method("#{name}=") do |part|
+              klass = class_name.constantize
 
-            unless part.is_a?(klass) || converter.nil? || part.nil?
-              part = converter.respond_to?(:call) ? converter.call(part) : klass.send(converter, part)
-            end
+              unless part.is_a?(klass) || converter.nil? || part.nil?
+                part = converter.respond_to?(:call) ? converter.call(part) : klass.send(converter, part)
+              end
 
-            if part.is_a?(Hash)
-              raise ArgumentError unless part.size == part.keys.max
-              part = klass.new(*part.sort.map(&:last))
-            end
+              hash_from_multiparameter_assignment = part.is_a?(Hash) &&
+                part.each_key.all? { |k| k.is_a?(Integer) }
+              if hash_from_multiparameter_assignment
+                raise ArgumentError unless part.size == part.each_key.max
+                part = klass.new(*part.sort.map(&:last))
+              end
 
-            if part.nil? && allow_nil
-              mapping.each { |key, _| self[key] = nil }
-              @aggregation_cache[name] = nil
-            else
-              mapping.each { |key, value| self[key] = part.send(value) }
-              @aggregation_cache[name] = part.freeze
+              if part.nil? && allow_nil
+                mapping.each { |key, _| self[key] = nil }
+                @aggregation_cache[name] = nil
+              else
+                mapping.each { |key, value| self[key] = part.send(value) }
+                @aggregation_cache[name] = part.freeze
+              end
             end
           end
-        end
-    end
+      end
   end
 end
diff --git a/activerecord/lib/active_record/association_relation.rb b/activerecord/lib/active_record/association_relation.rb
index c18e88e4cf..2b0b2864bc 100644
--- a/activerecord/lib/active_record/association_relation.rb
+++ b/activerecord/lib/active_record/association_relation.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActiveRecord
   class AssociationRelation < Relation
     def initialize(klass, table, predicate_builder, association)
@@ -28,8 +30,11 @@ module ActiveRecord
 
     private
 
-    def exec_queries
-      super.each { |r| @association.set_inverse_instance r }
-    end
+      def exec_queries
+        super do |r|
+          @association.set_inverse_instance r
+          yield r if block_given?
+        end
+      end
   end
 end
diff --git a/activerecord/lib/active_record/associations.rb b/activerecord/lib/active_record/associations.rb
index 3729e22e64..661605d3e5 100644
--- a/activerecord/lib/active_record/associations.rb
+++ b/activerecord/lib/active_record/associations.rb
@@ -1,7 +1,9 @@
-require 'active_support/core_ext/enumerable'
-require 'active_support/core_ext/string/conversions'
-require 'active_support/core_ext/module/remove_method'
-require 'active_record/errors'
+# frozen_string_literal: true
+
+require "active_support/core_ext/enumerable"
+require "active_support/core_ext/string/conversions"
+require "active_support/core_ext/module/remove_method"
+require "active_record/errors"
 
 module ActiveRecord
   class AssociationNotFoundError < ConfigurationError #:nodoc:
@@ -90,13 +92,23 @@ module ActiveRecord
         through_reflection      = reflection.through_reflection
         source_reflection_names = reflection.source_reflection_names
         source_associations     = reflection.through_reflection.klass._reflections.keys
-        super("Could not find the source association(s) #{source_reflection_names.collect(&:inspect).to_sentence(:two_words_connector => ' or ', :last_word_connector => ', or ', :locale => :en)} in model #{through_reflection.klass}. Try 'has_many #{reflection.name.inspect}, :through => #{through_reflection.name.inspect}, :source => <name>'. Is it one of #{source_associations.to_sentence(:two_words_connector => ' or ', :last_word_connector => ', or ', :locale => :en)}?")
+        super("Could not find the source association(s) #{source_reflection_names.collect(&:inspect).to_sentence(two_words_connector: ' or ', last_word_connector: ', or ', locale: :en)} in model #{through_reflection.klass}. Try 'has_many #{reflection.name.inspect}, :through => #{through_reflection.name.inspect}, :source => <name>'. Is it one of #{source_associations.to_sentence(two_words_connector: ' or ', last_word_connector: ', or ', locale: :en)}?")
       else
         super("Could not find the source association(s).")
       end
     end
   end
 
+  class HasManyThroughOrderError < ActiveRecordError #:nodoc:
+    def initialize(owner_class_name = nil, reflection = nil, through_reflection = nil)
+      if owner_class_name && reflection && through_reflection
+        super("Cannot have a has_many :through association '#{owner_class_name}##{reflection.name}' which goes through '#{owner_class_name}##{through_reflection.name}' before the through association is defined.")
+      else
+        super("Cannot have a has_many :through association before the through association is defined.")
+      end
+    end
+  end
+
   class ThroughCantAssociateThroughHasOneOrManyReflection < ActiveRecordError #:nodoc:
     def initialize(owner = nil, reflection = nil)
       if owner && reflection
@@ -107,30 +119,25 @@ module ActiveRecord
     end
   end
 
-  class HasManyThroughCantAssociateThroughHasOneOrManyReflection < ThroughCantAssociateThroughHasOneOrManyReflection #:nodoc:
-  end
+  class AmbiguousSourceReflectionForThroughAssociation < ActiveRecordError # :nodoc:
+    def initialize(klass, macro, association_name, options, possible_sources)
+      example_options = options.dup
+      example_options[:source] = possible_sources.first
 
-  class HasOneThroughCantAssociateThroughHasOneOrManyReflection < ThroughCantAssociateThroughHasOneOrManyReflection #:nodoc:
+      super("Ambiguous source reflection for through association. Please " \
+            "specify a :source directive on your declaration like:\n" \
+            "\n" \
+            "  class #{klass} < ActiveRecord::Base\n" \
+            "    #{macro} :#{association_name}, #{example_options}\n" \
+            "  end"
+           )
+    end
   end
 
-  class HasManyThroughCantAssociateNewRecords < ActiveRecordError #:nodoc:
-    def initialize(owner = nil, reflection = nil)
-      if owner && reflection
-        super("Cannot associate new records through '#{owner.class.name}##{reflection.name}' on '#{reflection.source_reflection.class_name rescue nil}##{reflection.source_reflection.name rescue nil}'. Both records must have an id in order to create the has_many :through record associating them.")
-      else
-        super("Cannot associate new records.")
-      end
-    end
+  class HasManyThroughCantAssociateThroughHasOneOrManyReflection < ThroughCantAssociateThroughHasOneOrManyReflection #:nodoc:
   end
 
-  class HasManyThroughCantDissociateNewRecords < ActiveRecordError #:nodoc:
-    def initialize(owner = nil, reflection = nil)
-      if owner && reflection
-        super("Cannot dissociate new records through '#{owner.class.name}##{reflection.name}' on '#{reflection.source_reflection.class_name rescue nil}##{reflection.source_reflection.name rescue nil}'. Both records must have an id in order to delete the has_many :through record associating them.")
-      else
-        super("Cannot dissociate new records.")
-      end
-    end
+  class HasOneThroughCantAssociateThroughHasOneOrManyReflection < ThroughCantAssociateThroughHasOneOrManyReflection #:nodoc:
   end
 
   class ThroughNestedAssociationsAreReadonly < ActiveRecordError #:nodoc:
@@ -162,16 +169,6 @@ module ActiveRecord
     end
   end
 
-  class ReadOnlyAssociation < ActiveRecordError #:nodoc:
-    def initialize(reflection = nil)
-      if reflection
-        super("Cannot add to a has_many :through association. Try adding to #{reflection.through_reflection.name.inspect}.")
-      else
-        super("Read-only reflection error.")
-      end
-    end
-  end
-
   # This error is raised when trying to destroy a parent instance in N:1 or 1:1 associations
   # (has_many, has_one) when there is at least 1 child associated instance.
   # ex: if @project.tasks.size > 0, DeleteRestrictionError will be raised when trying to destroy @project
@@ -197,33 +194,38 @@ module ActiveRecord
     autoload :CollectionAssociation
     autoload :ForeignAssociation
     autoload :CollectionProxy
-
-    autoload :BelongsToAssociation
-    autoload :BelongsToPolymorphicAssociation
-    autoload :HasManyAssociation
-    autoload :HasManyThroughAssociation
-    autoload :HasOneAssociation
-    autoload :HasOneThroughAssociation
     autoload :ThroughAssociation
 
     module Builder #:nodoc:
-      autoload :Association,           'active_record/associations/builder/association'
-      autoload :SingularAssociation,   'active_record/associations/builder/singular_association'
-      autoload :CollectionAssociation, 'active_record/associations/builder/collection_association'
+      autoload :Association,           "active_record/associations/builder/association"
+      autoload :SingularAssociation,   "active_record/associations/builder/singular_association"
+      autoload :CollectionAssociation, "active_record/associations/builder/collection_association"
 
-      autoload :BelongsTo,           'active_record/associations/builder/belongs_to'
-      autoload :HasOne,              'active_record/associations/builder/has_one'
-      autoload :HasMany,             'active_record/associations/builder/has_many'
-      autoload :HasAndBelongsToMany, 'active_record/associations/builder/has_and_belongs_to_many'
+      autoload :BelongsTo,           "active_record/associations/builder/belongs_to"
+      autoload :HasOne,              "active_record/associations/builder/has_one"
+      autoload :HasMany,             "active_record/associations/builder/has_many"
+      autoload :HasAndBelongsToMany, "active_record/associations/builder/has_and_belongs_to_many"
     end
 
     eager_autoload do
+      autoload :BelongsToAssociation
+      autoload :BelongsToPolymorphicAssociation
+      autoload :HasManyAssociation
+      autoload :HasManyThroughAssociation
+      autoload :HasOneAssociation
+      autoload :HasOneThroughAssociation
+
       autoload :Preloader
       autoload :JoinDependency
       autoload :AssociationScope
       autoload :AliasTracker
     end
 
+    def self.eager_load!
+      super
+      Preloader.eager_load!
+    end
+
     # Returns the association instance for the given name, instantiating it if it doesn't already exist
     def association(name) #:nodoc:
       association = association_instance_get(name)
@@ -255,16 +257,16 @@ module ActiveRecord
 
     private
       # Clears out the association cache.
-      def clear_association_cache # :nodoc:
+      def clear_association_cache
         @association_cache.clear if persisted?
       end
 
-      def init_internals # :nodoc:
+      def init_internals
         @association_cache = {}
         super
       end
 
-      # Returns the specified association instance if it exists, nil otherwise.
+      # Returns the specified association instance if it exists, +nil+ otherwise.
       def association_instance_get(name)
         @association_cache[name]
       end
@@ -274,1560 +276,1579 @@ module ActiveRecord
         @association_cache[name] = association
       end
 
-    # \Associations are a set of macro-like class methods for tying objects together through
-    # foreign keys. They express relationships like "Project has one Project Manager"
-    # or "Project belongs to a Portfolio". Each macro adds a number of methods to the
-    # class which are specialized according to the collection or association symbol and the
-    # options hash. It works much the same way as Ruby's own <tt>attr*</tt>
-    # methods.
-    #
-    #   class Project < ActiveRecord::Base
-    #     belongs_to              :portfolio
-    #     has_one                 :project_manager
-    #     has_many                :milestones
-    #     has_and_belongs_to_many :categories
-    #   end
-    #
-    # The project class now has the following methods (and more) to ease the traversal and
-    # manipulation of its relationships:
-    # * <tt>Project#portfolio, Project#portfolio=(portfolio), Project#portfolio.nil?</tt>
-    # * <tt>Project#project_manager, Project#project_manager=(project_manager), Project#project_manager.nil?,</tt>
-    # * <tt>Project#milestones.empty?, Project#milestones.size, Project#milestones, Project#milestones<<(milestone),</tt>
-    #   <tt>Project#milestones.delete(milestone), Project#milestones.destroy(milestone), Project#milestones.find(milestone_id),</tt>
-    #   <tt>Project#milestones.build, Project#milestones.create</tt>
-    # * <tt>Project#categories.empty?, Project#categories.size, Project#categories, Project#categories<<(category1),</tt>
-    #   <tt>Project#categories.delete(category1), Project#categories.destroy(category1)</tt>
-    #
-    # === A word of warning
-    #
-    # Don't create associations that have the same name as {instance methods}[rdoc-ref:ActiveRecord::Core] of
-    # <tt>ActiveRecord::Base</tt>. Since the association adds a method with that name to
-    # its model, using an association with the same name as one provided by <tt>ActiveRecord::Base</tt> will override the method inherited through <tt>ActiveRecord::Base</tt> and will break things.
-    # For instance, +attributes+ and +connection+ would be bad choices for association names, because those names already exist in the list of <tt>ActiveRecord::Base</tt> instance methods.
-    #
-    # == Auto-generated methods
-    # See also Instance Public methods below for more details.
-    #
-    # === Singular associations (one-to-one)
-    #                                     |            |  belongs_to  |
-    #   generated methods                 | belongs_to | :polymorphic | has_one
-    #   ----------------------------------+------------+--------------+---------
-    #   other(force_reload=false)         |     X      |      X       |    X
-    #   other=(other)                     |     X      |      X       |    X
-    #   build_other(attributes={})        |     X      |              |    X
-    #   create_other(attributes={})       |     X      |              |    X
-    #   create_other!(attributes={})      |     X      |              |    X
-    #
-    # === Collection associations (one-to-many / many-to-many)
-    #                                     |       |          | has_many
-    #   generated methods                 | habtm | has_many | :through
-    #   ----------------------------------+-------+----------+----------
-    #   others(force_reload=false)        |   X   |    X     |    X
-    #   others=(other,other,...)          |   X   |    X     |    X
-    #   other_ids                         |   X   |    X     |    X
-    #   other_ids=(id,id,...)             |   X   |    X     |    X
-    #   others<<                          |   X   |    X     |    X
-    #   others.push                       |   X   |    X     |    X
-    #   others.concat                     |   X   |    X     |    X
-    #   others.build(attributes={})       |   X   |    X     |    X
-    #   others.create(attributes={})      |   X   |    X     |    X
-    #   others.create!(attributes={})     |   X   |    X     |    X
-    #   others.size                       |   X   |    X     |    X
-    #   others.length                     |   X   |    X     |    X
-    #   others.count                      |   X   |    X     |    X
-    #   others.sum(*args)                 |   X   |    X     |    X
-    #   others.empty?                     |   X   |    X     |    X
-    #   others.clear                      |   X   |    X     |    X
-    #   others.delete(other,other,...)    |   X   |    X     |    X
-    #   others.delete_all                 |   X   |    X     |    X
-    #   others.destroy(other,other,...)   |   X   |    X     |    X
-    #   others.destroy_all                |   X   |    X     |    X
-    #   others.find(*args)                |   X   |    X     |    X
-    #   others.exists?                    |   X   |    X     |    X
-    #   others.distinct                   |   X   |    X     |    X
-    #   others.reset                      |   X   |    X     |    X
-    #
-    # === Overriding generated methods
-    #
-    # Association methods are generated in a module that is included into the model class,
-    # which allows you to easily override with your own methods and call the original
-    # generated method with +super+. For example:
-    #
-    #   class Car < ActiveRecord::Base
-    #     belongs_to :owner
-    #     belongs_to :old_owner
-    #     def owner=(new_owner)
-    #       self.old_owner = self.owner
-    #       super
-    #     end
-    #   end
-    #
-    # If your model class is <tt>Project</tt>, the module is
-    # named <tt>Project::GeneratedAssociationMethods</tt>. The +GeneratedAssociationMethods+ module is
-    # included in the model class immediately after the (anonymous) generated attributes methods
-    # module, meaning an association will override the methods for an attribute with the same name.
-    #
-    # == Cardinality and associations
-    #
-    # Active Record associations can be used to describe one-to-one, one-to-many and many-to-many
-    # relationships between models. Each model uses an association to describe its role in
-    # the relation. The #belongs_to association is always used in the model that has
-    # the foreign key.
-    #
-    # === One-to-one
-    #
-    # Use #has_one in the base, and #belongs_to in the associated model.
-    #
-    #   class Employee < ActiveRecord::Base
-    #     has_one :office
-    #   end
-    #   class Office < ActiveRecord::Base
-    #     belongs_to :employee    # foreign key - employee_id
-    #   end
-    #
-    # === One-to-many
-    #
-    # Use #has_many in the base, and #belongs_to in the associated model.
-    #
-    #   class Manager < ActiveRecord::Base
-    #     has_many :employees
-    #   end
-    #   class Employee < ActiveRecord::Base
-    #     belongs_to :manager     # foreign key - manager_id
-    #   end
-    #
-    # === Many-to-many
-    #
-    # There are two ways to build a many-to-many relationship.
-    #
-    # The first way uses a #has_many association with the <tt>:through</tt> option and a join model, so
-    # there are two stages of associations.
-    #
-    #   class Assignment < ActiveRecord::Base
-    #     belongs_to :programmer  # foreign key - programmer_id
-    #     belongs_to :project     # foreign key - project_id
-    #   end
-    #   class Programmer < ActiveRecord::Base
-    #     has_many :assignments
-    #     has_many :projects, through: :assignments
-    #   end
-    #   class Project < ActiveRecord::Base
-    #     has_many :assignments
-    #     has_many :programmers, through: :assignments
-    #   end
-    #
-    # For the second way, use #has_and_belongs_to_many in both models. This requires a join table
-    # that has no corresponding model or primary key.
-    #
-    #   class Programmer < ActiveRecord::Base
-    #     has_and_belongs_to_many :projects       # foreign keys in the join table
-    #   end
-    #   class Project < ActiveRecord::Base
-    #     has_and_belongs_to_many :programmers    # foreign keys in the join table
-    #   end
-    #
-    # Choosing which way to build a many-to-many relationship is not always simple.
-    # If you need to work with the relationship model as its own entity,
-    # use #has_many <tt>:through</tt>. Use #has_and_belongs_to_many when working with legacy schemas or when
-    # you never work directly with the relationship itself.
-    #
-    # == Is it a #belongs_to or #has_one association?
-    #
-    # Both express a 1-1 relationship. The difference is mostly where to place the foreign
-    # key, which goes on the table for the class declaring the #belongs_to relationship.
-    #
-    #   class User < ActiveRecord::Base
-    #     # I reference an account.
-    #     belongs_to :account
-    #   end
-    #
-    #   class Account < ActiveRecord::Base
-    #     # One user references me.
-    #     has_one :user
-    #   end
-    #
-    # The tables for these classes could look something like:
-    #
-    #   CREATE TABLE users (
-    #     id int NOT NULL auto_increment,
-    #     account_id int default NULL,
-    #     name varchar default NULL,
-    #     PRIMARY KEY  (id)
-    #   )
-    #
-    #   CREATE TABLE accounts (
-    #     id int NOT NULL auto_increment,
-    #     name varchar default NULL,
-    #     PRIMARY KEY  (id)
-    #   )
-    #
-    # == Unsaved objects and associations
-    #
-    # You can manipulate objects and associations before they are saved to the database, but
-    # there is some special behavior you should be aware of, mostly involving the saving of
-    # associated objects.
-    #
-    # You can set the <tt>:autosave</tt> option on a #has_one, #belongs_to,
-    # #has_many, or #has_and_belongs_to_many association. Setting it
-    # to +true+ will _always_ save the members, whereas setting it to +false+ will
-    # _never_ save the members. More details about <tt>:autosave</tt> option is available at
-    # AutosaveAssociation.
-    #
-    # === One-to-one associations
-    #
-    # * Assigning an object to a #has_one association automatically saves that object and
-    #   the object being replaced (if there is one), in order to update their foreign
-    #   keys - except if the parent object is unsaved (<tt>new_record? == true</tt>).
-    # * If either of these saves fail (due to one of the objects being invalid), an
-    #   ActiveRecord::RecordNotSaved exception is raised and the assignment is
-    #   cancelled.
-    # * If you wish to assign an object to a #has_one association without saving it,
-    #   use the <tt>#build_association</tt> method (documented below). The object being
-    #   replaced will still be saved to update its foreign key.
-    # * Assigning an object to a #belongs_to association does not save the object, since
-    #   the foreign key field belongs on the parent. It does not save the parent either.
-    #
-    # === Collections
-    #
-    # * Adding an object to a collection (#has_many or #has_and_belongs_to_many) automatically
-    #   saves that object, except if the parent object (the owner of the collection) is not yet
-    #   stored in the database.
-    # * If saving any of the objects being added to a collection (via <tt>push</tt> or similar)
-    #   fails, then <tt>push</tt> returns +false+.
-    # * If saving fails while replacing the collection (via <tt>association=</tt>), an
-    #   ActiveRecord::RecordNotSaved exception is raised and the assignment is
-    #   cancelled.
-    # * You can add an object to a collection without automatically saving it by using the
-    #   <tt>collection.build</tt> method (documented below).
-    # * All unsaved (<tt>new_record? == true</tt>) members of the collection are automatically
-    #   saved when the parent is saved.
-    #
-    # == Customizing the query
-    #
-    # \Associations are built from <tt>Relation</tt> objects, and you can use the Relation syntax
-    # to customize them. For example, to add a condition:
-    #
-    #   class Blog < ActiveRecord::Base
-    #     has_many :published_posts, -> { where(published: true) }, class_name: 'Post'
-    #   end
-    #
-    # Inside the <tt>-> { ... }</tt> block you can use all of the usual Relation methods.
-    #
-    # === Accessing the owner object
-    #
-    # Sometimes it is useful to have access to the owner object when building the query. The owner
-    # is passed as a parameter to the block. For example, the following association would find all
-    # events that occur on the user's birthday:
-    #
-    #   class User < ActiveRecord::Base
-    #     has_many :birthday_events, ->(user) { where(starts_on: user.birthday) }, class_name: 'Event'
-    #   end
-    #
-    # Note: Joining, eager loading and preloading of these associations is not fully possible.
-    # These operations happen before instance creation and the scope will be called with a +nil+ argument.
-    # This can lead to unexpected behavior and is deprecated.
-    #
-    # == Association callbacks
-    #
-    # Similar to the normal callbacks that hook into the life cycle of an Active Record object,
-    # you can also define callbacks that get triggered when you add an object to or remove an
-    # object from an association collection.
-    #
-    #   class Project
-    #     has_and_belongs_to_many :developers, after_add: :evaluate_velocity
-    #
-    #     def evaluate_velocity(developer)
-    #       ...
-    #     end
-    #   end
-    #
-    # It's possible to stack callbacks by passing them as an array. Example:
-    #
-    #   class Project
-    #     has_and_belongs_to_many :developers,
-    #                             after_add: [:evaluate_velocity, Proc.new { |p, d| p.shipping_date = Time.now}]
-    #   end
-    #
-    # Possible callbacks are: +before_add+, +after_add+, +before_remove+ and +after_remove+.
-    #
-    # If any of the +before_add+ callbacks throw an exception, the object will not be
-    # added to the collection.
-    #
-    # Similarly, if any of the +before_remove+ callbacks throw an exception, the object
-    # will not be removed from the collection.
-    #
-    # == Association extensions
-    #
-    # The proxy objects that control the access to associations can be extended through anonymous
-    # modules. This is especially beneficial for adding new finders, creators, and other
-    # factory-type methods that are only used as part of this association.
-    #
-    #   class Account < ActiveRecord::Base
-    #     has_many :people do
-    #       def find_or_create_by_name(name)
-    #         first_name, last_name = name.split(" ", 2)
-    #         find_or_create_by(first_name: first_name, last_name: last_name)
-    #       end
-    #     end
-    #   end
-    #
-    #   person = Account.first.people.find_or_create_by_name("David Heinemeier Hansson")
-    #   person.first_name # => "David"
-    #   person.last_name  # => "Heinemeier Hansson"
-    #
-    # If you need to share the same extensions between many associations, you can use a named
-    # extension module.
-    #
-    #   module FindOrCreateByNameExtension
-    #     def find_or_create_by_name(name)
-    #       first_name, last_name = name.split(" ", 2)
-    #       find_or_create_by(first_name: first_name, last_name: last_name)
-    #     end
-    #   end
-    #
-    #   class Account < ActiveRecord::Base
-    #     has_many :people, -> { extending FindOrCreateByNameExtension }
-    #   end
-    #
-    #   class Company < ActiveRecord::Base
-    #     has_many :people, -> { extending FindOrCreateByNameExtension }
-    #   end
-    #
-    # Some extensions can only be made to work with knowledge of the association's internals.
-    # Extensions can access relevant state using the following methods (where +items+ is the
-    # name of the association):
-    #
-    # * <tt>record.association(:items).owner</tt> - Returns the object the association is part of.
-    # * <tt>record.association(:items).reflection</tt> - Returns the reflection object that describes the association.
-    # * <tt>record.association(:items).target</tt> - Returns the associated object for #belongs_to and #has_one, or
-    #   the collection of associated objects for #has_many and #has_and_belongs_to_many.
-    #
-    # However, inside the actual extension code, you will not have access to the <tt>record</tt> as
-    # above. In this case, you can access <tt>proxy_association</tt>. For example,
-    # <tt>record.association(:items)</tt> and <tt>record.items.proxy_association</tt> will return
-    # the same object, allowing you to make calls like <tt>proxy_association.owner</tt> inside
-    # association extensions.
-    #
-    # == Association Join Models
-    #
-    # Has Many associations can be configured with the <tt>:through</tt> option to use an
-    # explicit join model to retrieve the data. This operates similarly to a
-    # #has_and_belongs_to_many association. The advantage is that you're able to add validations,
-    # callbacks, and extra attributes on the join model. Consider the following schema:
-    #
-    #   class Author < ActiveRecord::Base
-    #     has_many :authorships
-    #     has_many :books, through: :authorships
-    #   end
-    #
-    #   class Authorship < ActiveRecord::Base
-    #     belongs_to :author
-    #     belongs_to :book
-    #   end
-    #
-    #   @author = Author.first
-    #   @author.authorships.collect { |a| a.book } # selects all books that the author's authorships belong to
-    #   @author.books                              # selects all books by using the Authorship join model
-    #
-    # You can also go through a #has_many association on the join model:
-    #
-    #   class Firm < ActiveRecord::Base
-    #     has_many   :clients
-    #     has_many   :invoices, through: :clients
-    #   end
-    #
-    #   class Client < ActiveRecord::Base
-    #     belongs_to :firm
-    #     has_many   :invoices
-    #   end
-    #
-    #   class Invoice < ActiveRecord::Base
-    #     belongs_to :client
-    #   end
-    #
-    #   @firm = Firm.first
-    #   @firm.clients.flat_map { |c| c.invoices } # select all invoices for all clients of the firm
-    #   @firm.invoices                            # selects all invoices by going through the Client join model
-    #
-    # Similarly you can go through a #has_one association on the join model:
-    #
-    #   class Group < ActiveRecord::Base
-    #     has_many   :users
-    #     has_many   :avatars, through: :users
-    #   end
-    #
-    #   class User < ActiveRecord::Base
-    #     belongs_to :group
-    #     has_one    :avatar
-    #   end
-    #
-    #   class Avatar < ActiveRecord::Base
-    #     belongs_to :user
-    #   end
-    #
-    #   @group = Group.first
-    #   @group.users.collect { |u| u.avatar }.compact # select all avatars for all users in the group
-    #   @group.avatars                                # selects all avatars by going through the User join model.
-    #
-    # An important caveat with going through #has_one or #has_many associations on the
-    # join model is that these associations are *read-only*. For example, the following
-    # would not work following the previous example:
-    #
-    #   @group.avatars << Avatar.new   # this would work if User belonged_to Avatar rather than the other way around
-    #   @group.avatars.delete(@group.avatars.last)  # so would this
-    #
-    # == Setting Inverses
-    #
-    # If you are using a #belongs_to on the join model, it is a good idea to set the
-    # <tt>:inverse_of</tt> option on the #belongs_to, which will mean that the following example
-    # works correctly (where <tt>tags</tt> is a #has_many <tt>:through</tt> association):
-    #
-    #   @post = Post.first
-    #   @tag = @post.tags.build name: "ruby"
-    #   @tag.save
-    #
-    # The last line ought to save the through record (a <tt>Tagging</tt>). This will only work if the
-    # <tt>:inverse_of</tt> is set:
-    #
-    #   class Tagging < ActiveRecord::Base
-    #     belongs_to :post
-    #     belongs_to :tag, inverse_of: :taggings
-    #   end
-    #
-    # If you do not set the <tt>:inverse_of</tt> record, the association will
-    # do its best to match itself up with the correct inverse. Automatic
-    # inverse detection only works on #has_many, #has_one, and
-    # #belongs_to associations.
-    #
-    # Extra options on the associations, as defined in the
-    # <tt>AssociationReflection::INVALID_AUTOMATIC_INVERSE_OPTIONS</tt> constant, will
-    # also prevent the association's inverse from being found automatically.
-    #
-    # The automatic guessing of the inverse association uses a heuristic based
-    # on the name of the class, so it may not work for all associations,
-    # especially the ones with non-standard names.
-    #
-    # You can turn off the automatic detection of inverse associations by setting
-    # the <tt>:inverse_of</tt> option to <tt>false</tt> like so:
-    #
-    #   class Tagging < ActiveRecord::Base
-    #     belongs_to :tag, inverse_of: false
-    #   end
-    #
-    # == Nested \Associations
-    #
-    # You can actually specify *any* association with the <tt>:through</tt> option, including an
-    # association which has a <tt>:through</tt> option itself. For example:
-    #
-    #   class Author < ActiveRecord::Base
-    #     has_many :posts
-    #     has_many :comments, through: :posts
-    #     has_many :commenters, through: :comments
-    #   end
-    #
-    #   class Post < ActiveRecord::Base
-    #     has_many :comments
-    #   end
-    #
-    #   class Comment < ActiveRecord::Base
-    #     belongs_to :commenter
-    #   end
-    #
-    #   @author = Author.first
-    #   @author.commenters # => People who commented on posts written by the author
-    #
-    # An equivalent way of setting up this association this would be:
-    #
-    #   class Author < ActiveRecord::Base
-    #     has_many :posts
-    #     has_many :commenters, through: :posts
-    #   end
-    #
-    #   class Post < ActiveRecord::Base
-    #     has_many :comments
-    #     has_many :commenters, through: :comments
-    #   end
-    #
-    #   class Comment < ActiveRecord::Base
-    #     belongs_to :commenter
-    #   end
-    #
-    # When using a nested association, you will not be able to modify the association because there
-    # is not enough information to know what modification to make. For example, if you tried to
-    # add a <tt>Commenter</tt> in the example above, there would be no way to tell how to set up the
-    # intermediate <tt>Post</tt> and <tt>Comment</tt> objects.
-    #
-    # == Polymorphic \Associations
-    #
-    # Polymorphic associations on models are not restricted on what types of models they
-    # can be associated with. Rather, they specify an interface that a #has_many association
-    # must adhere to.
-    #
-    #   class Asset < ActiveRecord::Base
-    #     belongs_to :attachable, polymorphic: true
-    #   end
-    #
-    #   class Post < ActiveRecord::Base
-    #     has_many :assets, as: :attachable         # The :as option specifies the polymorphic interface to use.
-    #   end
-    #
-    #   @asset.attachable = @post
-    #
-    # This works by using a type column in addition to a foreign key to specify the associated
-    # record. In the Asset example, you'd need an +attachable_id+ integer column and an
-    # +attachable_type+ string column.
-    #
-    # Using polymorphic associations in combination with single table inheritance (STI) is
-    # a little tricky. In order for the associations to work as expected, ensure that you
-    # store the base model for the STI models in the type column of the polymorphic
-    # association. To continue with the asset example above, suppose there are guest posts
-    # and member posts that use the posts table for STI. In this case, there must be a +type+
-    # column in the posts table.
-    #
-    # Note: The <tt>attachable_type=</tt> method is being called when assigning an +attachable+.
-    # The +class_name+ of the +attachable+ is passed as a String.
-    #
-    #   class Asset < ActiveRecord::Base
-    #     belongs_to :attachable, polymorphic: true
-    #
-    #     def attachable_type=(class_name)
-    #        super(class_name.constantize.base_class.to_s)
-    #     end
-    #   end
-    #
-    #   class Post < ActiveRecord::Base
-    #     # because we store "Post" in attachable_type now dependent: :destroy will work
-    #     has_many :assets, as: :attachable, dependent: :destroy
-    #   end
-    #
-    #   class GuestPost < Post
-    #   end
-    #
-    #   class MemberPost < Post
-    #   end
-    #
-    # == Caching
-    #
-    # All of the methods are built on a simple caching principle that will keep the result
-    # of the last query around unless specifically instructed not to. The cache is even
-    # shared across methods to make it even cheaper to use the macro-added methods without
-    # worrying too much about performance at the first go.
-    #
-    #   project.milestones             # fetches milestones from the database
-    #   project.milestones.size        # uses the milestone cache
-    #   project.milestones.empty?      # uses the milestone cache
-    #   project.milestones(true).size  # fetches milestones from the database
-    #   project.milestones             # uses the milestone cache
-    #
-    # == Eager loading of associations
-    #
-    # Eager loading is a way to find objects of a certain class and a number of named associations.
-    # It is one of the easiest ways to prevent the dreaded N+1 problem in which fetching 100
-    # posts that each need to display their author triggers 101 database queries. Through the
-    # use of eager loading, the number of queries will be reduced from 101 to 2.
-    #
-    #   class Post < ActiveRecord::Base
-    #     belongs_to :author
-    #     has_many   :comments
-    #   end
-    #
-    # Consider the following loop using the class above:
-    #
-    #   Post.all.each do |post|
-    #     puts "Post:            " + post.title
-    #     puts "Written by:      " + post.author.name
-    #     puts "Last comment on: " + post.comments.first.created_on
-    #   end
-    #
-    # To iterate over these one hundred posts, we'll generate 201 database queries. Let's
-    # first just optimize it for retrieving the author:
-    #
-    #   Post.includes(:author).each do |post|
-    #
-    # This references the name of the #belongs_to association that also used the <tt>:author</tt>
-    # symbol. After loading the posts, find will collect the +author_id+ from each one and load
-    # all the referenced authors with one query. Doing so will cut down the number of queries
-    # from 201 to 102.
-    #
-    # We can improve upon the situation further by referencing both associations in the finder with:
-    #
-    #   Post.includes(:author, :comments).each do |post|
-    #
-    # This will load all comments with a single query. This reduces the total number of queries
-    # to 3. In general, the number of queries will be 1 plus the number of associations
-    # named (except if some of the associations are polymorphic #belongs_to - see below).
-    #
-    # To include a deep hierarchy of associations, use a hash:
-    #
-    #   Post.includes(:author, { comments: { author: :gravatar } }).each do |post|
-    #
-    # The above code will load all the comments and all of their associated
-    # authors and gravatars. You can mix and match any combination of symbols,
-    # arrays, and hashes to retrieve the associations you want to load.
-    #
-    # All of this power shouldn't fool you into thinking that you can pull out huge amounts
-    # of data with no performance penalty just because you've reduced the number of queries.
-    # The database still needs to send all the data to Active Record and it still needs to
-    # be processed. So it's no catch-all for performance problems, but it's a great way to
-    # cut down on the number of queries in a situation as the one described above.
-    #
-    # Since only one table is loaded at a time, conditions or orders cannot reference tables
-    # other than the main one. If this is the case, Active Record falls back to the previously
-    # used LEFT OUTER JOIN based strategy. For example:
-    #
-    #   Post.includes([:author, :comments]).where(['comments.approved = ?', true])
-    #
-    # This will result in a single SQL query with joins along the lines of:
-    # <tt>LEFT OUTER JOIN comments ON comments.post_id = posts.id</tt> and
-    # <tt>LEFT OUTER JOIN authors ON authors.id = posts.author_id</tt>. Note that using conditions
-    # like this can have unintended consequences.
-    # In the above example posts with no approved comments are not returned at all, because
-    # the conditions apply to the SQL statement as a whole and not just to the association.
-    #
-    # You must disambiguate column references for this fallback to happen, for example
-    # <tt>order: "author.name DESC"</tt> will work but <tt>order: "name DESC"</tt> will not.
-    #
-    # If you want to load all posts (including posts with no approved comments) then write
-    # your own LEFT OUTER JOIN query using ON
-    #
-    #   Post.joins("LEFT OUTER JOIN comments ON comments.post_id = posts.id AND comments.approved = '1'")
-    #
-    # In this case it is usually more natural to include an association which has conditions defined on it:
-    #
-    #   class Post < ActiveRecord::Base
-    #     has_many :approved_comments, -> { where(approved: true) }, class_name: 'Comment'
-    #   end
-    #
-    #   Post.includes(:approved_comments)
-    #
-    # This will load posts and eager load the +approved_comments+ association, which contains
-    # only those comments that have been approved.
-    #
-    # If you eager load an association with a specified <tt>:limit</tt> option, it will be ignored,
-    # returning all the associated objects:
-    #
-    #   class Picture < ActiveRecord::Base
-    #     has_many :most_recent_comments, -> { order('id DESC').limit(10) }, class_name: 'Comment'
-    #   end
-    #
-    #   Picture.includes(:most_recent_comments).first.most_recent_comments # => returns all associated comments.
-    #
-    # Eager loading is supported with polymorphic associations.
-    #
-    #   class Address < ActiveRecord::Base
-    #     belongs_to :addressable, polymorphic: true
-    #   end
-    #
-    # A call that tries to eager load the addressable model
-    #
-    #   Address.includes(:addressable)
-    #
-    # This will execute one query to load the addresses and load the addressables with one
-    # query per addressable type.
-    # For example if all the addressables are either of class Person or Company then a total
-    # of 3 queries will be executed. The list of addressable types to load is determined on
-    # the back of the addresses loaded. This is not supported if Active Record has to fallback
-    # to the previous implementation of eager loading and will raise ActiveRecord::EagerLoadPolymorphicError.
-    # The reason is that the parent model's type is a column value so its corresponding table
-    # name cannot be put in the +FROM+/+JOIN+ clauses of that query.
-    #
-    # == Table Aliasing
-    #
-    # Active Record uses table aliasing in the case that a table is referenced multiple times
-    # in a join. If a table is referenced only once, the standard table name is used. The
-    # second time, the table is aliased as <tt>#{reflection_name}_#{parent_table_name}</tt>.
-    # Indexes are appended for any more successive uses of the table name.
-    #
-    #   Post.joins(:comments)
-    #   # => SELECT ... FROM posts INNER JOIN comments ON ...
-    #   Post.joins(:special_comments) # STI
-    #   # => SELECT ... FROM posts INNER JOIN comments ON ... AND comments.type = 'SpecialComment'
-    #   Post.joins(:comments, :special_comments) # special_comments is the reflection name, posts is the parent table name
-    #   # => SELECT ... FROM posts INNER JOIN comments ON ... INNER JOIN comments special_comments_posts
-    #
-    # Acts as tree example:
-    #
-    #   TreeMixin.joins(:children)
-    #   # => SELECT ... FROM mixins INNER JOIN mixins childrens_mixins ...
-    #   TreeMixin.joins(children: :parent)
-    #   # => SELECT ... FROM mixins INNER JOIN mixins childrens_mixins ...
-    #                               INNER JOIN parents_mixins ...
-    #   TreeMixin.joins(children: {parent: :children})
-    #   # => SELECT ... FROM mixins INNER JOIN mixins childrens_mixins ...
-    #                               INNER JOIN parents_mixins ...
-    #                               INNER JOIN mixins childrens_mixins_2
-    #
-    # Has and Belongs to Many join tables use the same idea, but add a <tt>_join</tt> suffix:
-    #
-    #   Post.joins(:categories)
-    #   # => SELECT ... FROM posts INNER JOIN categories_posts ... INNER JOIN categories ...
-    #   Post.joins(categories: :posts)
-    #   # => SELECT ... FROM posts INNER JOIN categories_posts ... INNER JOIN categories ...
-    #                              INNER JOIN categories_posts posts_categories_join INNER JOIN posts posts_categories
-    #   Post.joins(categories: {posts: :categories})
-    #   # => SELECT ... FROM posts INNER JOIN categories_posts ... INNER JOIN categories ...
-    #                              INNER JOIN categories_posts posts_categories_join INNER JOIN posts posts_categories
-    #                              INNER JOIN categories_posts categories_posts_join INNER JOIN categories categories_posts_2
-    #
-    # If you wish to specify your own custom joins using ActiveRecord::QueryMethods#joins method, those table
-    # names will take precedence over the eager associations:
-    #
-    #   Post.joins(:comments).joins("inner join comments ...")
-    #   # => SELECT ... FROM posts INNER JOIN comments_posts ON ... INNER JOIN comments ...
-    #   Post.joins(:comments, :special_comments).joins("inner join comments ...")
-    #   # => SELECT ... FROM posts INNER JOIN comments comments_posts ON ...
-    #                              INNER JOIN comments special_comments_posts ...
-    #                              INNER JOIN comments ...
-    #
-    # Table aliases are automatically truncated according to the maximum length of table identifiers
-    # according to the specific database.
-    #
-    # == Modules
-    #
-    # By default, associations will look for objects within the current module scope. Consider:
-    #
-    #   module MyApplication
-    #     module Business
-    #       class Firm < ActiveRecord::Base
-    #         has_many :clients
-    #       end
-    #
-    #       class Client < ActiveRecord::Base; end
-    #     end
-    #   end
-    #
-    # When <tt>Firm#clients</tt> is called, it will in turn call
-    # <tt>MyApplication::Business::Client.find_all_by_firm_id(firm.id)</tt>.
-    # If you want to associate with a class in another module scope, this can be done by
-    # specifying the complete class name.
-    #
-    #   module MyApplication
-    #     module Business
-    #       class Firm < ActiveRecord::Base; end
-    #     end
-    #
-    #     module Billing
-    #       class Account < ActiveRecord::Base
-    #         belongs_to :firm, class_name: "MyApplication::Business::Firm"
-    #       end
-    #     end
-    #   end
-    #
-    # == Bi-directional associations
-    #
-    # When you specify an association there is usually an association on the associated model
-    # that specifies the same relationship in reverse. For example, with the following models:
-    #
-    #    class Dungeon < ActiveRecord::Base
-    #      has_many :traps
-    #      has_one :evil_wizard
-    #    end
-    #
-    #    class Trap < ActiveRecord::Base
-    #      belongs_to :dungeon
-    #    end
-    #
-    #    class EvilWizard < ActiveRecord::Base
-    #      belongs_to :dungeon
-    #    end
-    #
-    # The +traps+ association on +Dungeon+ and the +dungeon+ association on +Trap+ are
-    # the inverse of each other and the inverse of the +dungeon+ association on +EvilWizard+
-    # is the +evil_wizard+ association on +Dungeon+ (and vice-versa). By default,
-    # Active Record can guess the inverse of the association based on the name
-    # of the class. The result is the following:
-    #
-    #    d = Dungeon.first
-    #    t = d.traps.first
-    #    d.object_id == t.dungeon.object_id # => true
-    #
-    # The +Dungeon+ instances +d+ and <tt>t.dungeon</tt> in the above example refer to
-    # the same in-memory instance since the association matches the name of the class.
-    # The result would be the same if we added +:inverse_of+ to our model definitions:
-    #
-    #    class Dungeon < ActiveRecord::Base
-    #      has_many :traps, inverse_of: :dungeon
-    #      has_one :evil_wizard, inverse_of: :dungeon
-    #    end
-    #
-    #    class Trap < ActiveRecord::Base
-    #      belongs_to :dungeon, inverse_of: :traps
-    #    end
-    #
-    #    class EvilWizard < ActiveRecord::Base
-    #      belongs_to :dungeon, inverse_of: :evil_wizard
-    #    end
-    #
-    # There are limitations to <tt>:inverse_of</tt> support:
-    #
-    # * does not work with <tt>:through</tt> associations.
-    # * does not work with <tt>:polymorphic</tt> associations.
-    # * for #belongs_to associations #has_many inverse associations are ignored.
-    #
-    # For more information, see the documentation for the +:inverse_of+ option.
-    #
-    # == Deleting from associations
-    #
-    # === Dependent associations
-    #
-    # #has_many, #has_one and #belongs_to associations support the <tt>:dependent</tt> option.
-    # This allows you to specify that associated records should be deleted when the owner is
-    # deleted.
-    #
-    # For example:
-    #
-    #     class Author
-    #       has_many :posts, dependent: :destroy
-    #     end
-    #     Author.find(1).destroy # => Will destroy all of the author's posts, too
-    #
-    # The <tt>:dependent</tt> option can have different values which specify how the deletion
-    # is done. For more information, see the documentation for this option on the different
-    # specific association types. When no option is given, the behavior is to do nothing
-    # with the associated records when destroying a record.
-    #
-    # Note that <tt>:dependent</tt> is implemented using Rails' callback
-    # system, which works by processing callbacks in order. Therefore, other
-    # callbacks declared either before or after the <tt>:dependent</tt> option
-    # can affect what it does.
-    #
-    # Note that <tt>:dependent</tt> option is ignored for #has_one <tt>:through</tt> associations.
-    #
-    # === Delete or destroy?
-    #
-    # #has_many and #has_and_belongs_to_many associations have the methods <tt>destroy</tt>,
-    # <tt>delete</tt>, <tt>destroy_all</tt> and <tt>delete_all</tt>.
-    #
-    # For #has_and_belongs_to_many, <tt>delete</tt> and <tt>destroy</tt> are the same: they
-    # cause the records in the join table to be removed.
-    #
-    # For #has_many, <tt>destroy</tt> and <tt>destroy_all</tt> will always call the <tt>destroy</tt> method of the
-    # record(s) being removed so that callbacks are run. However <tt>delete</tt> and <tt>delete_all</tt> will either
-    # do the deletion according to the strategy specified by the <tt>:dependent</tt> option, or
-    # if no <tt>:dependent</tt> option is given, then it will follow the default strategy.
-    # The default strategy is to do nothing (leave the foreign keys with the parent ids set), except for
-    # #has_many <tt>:through</tt>, where the default strategy is <tt>delete_all</tt> (delete
-    # the join records, without running their callbacks).
-    #
-    # There is also a <tt>clear</tt> method which is the same as <tt>delete_all</tt>, except that
-    # it returns the association rather than the records which have been deleted.
-    #
-    # === What gets deleted?
-    #
-    # There is a potential pitfall here: #has_and_belongs_to_many and #has_many <tt>:through</tt>
-    # associations have records in join tables, as well as the associated records. So when we
-    # call one of these deletion methods, what exactly should be deleted?
-    #
-    # The answer is that it is assumed that deletion on an association is about removing the
-    # <i>link</i> between the owner and the associated object(s), rather than necessarily the
-    # associated objects themselves. So with #has_and_belongs_to_many and #has_many
-    # <tt>:through</tt>, the join records will be deleted, but the associated records won't.
-    #
-    # This makes sense if you think about it: if you were to call <tt>post.tags.delete(Tag.find_by(name: 'food'))</tt>
-    # you would want the 'food' tag to be unlinked from the post, rather than for the tag itself
-    # to be removed from the database.
-    #
-    # However, there are examples where this strategy doesn't make sense. For example, suppose
-    # a person has many projects, and each project has many tasks. If we deleted one of a person's
-    # tasks, we would probably not want the project to be deleted. In this scenario, the delete method
-    # won't actually work: it can only be used if the association on the join model is a
-    # #belongs_to. In other situations you are expected to perform operations directly on
-    # either the associated records or the <tt>:through</tt> association.
-    #
-    # With a regular #has_many there is no distinction between the "associated records"
-    # and the "link", so there is only one choice for what gets deleted.
-    #
-    # With #has_and_belongs_to_many and #has_many <tt>:through</tt>, if you want to delete the
-    # associated records themselves, you can always do something along the lines of
-    # <tt>person.tasks.each(&:destroy)</tt>.
-    #
-    # == Type safety with ActiveRecord::AssociationTypeMismatch
-    #
-    # If you attempt to assign an object to an association that doesn't match the inferred
-    # or specified <tt>:class_name</tt>, you'll get an ActiveRecord::AssociationTypeMismatch.
-    #
-    # == Options
-    #
-    # All of the association macros can be specialized through options. This makes cases
-    # more complex than the simple and guessable ones possible.
-    module ClassMethods
-      # Specifies a one-to-many association. The following methods for retrieval and query of
-      # collections of associated objects will be added:
-      #
-      # +collection+ is a placeholder for the symbol passed as the +name+ argument, so
-      # <tt>has_many :clients</tt> would add among others <tt>clients.empty?</tt>.
-      #
-      # [collection(force_reload = false)]
-      #   Returns an array of all the associated objects.
-      #   An empty array is returned if none are found.
-      # [collection<<(object, ...)]
-      #   Adds one or more objects to the collection by setting their foreign keys to the collection's primary key.
-      #   Note that this operation instantly fires update SQL without waiting for the save or update call on the
-      #   parent object, unless the parent object is a new record.
-      #   This will also run validations and callbacks of associated object(s).
-      # [collection.delete(object, ...)]
-      #   Removes one or more objects from the collection by setting their foreign keys to +NULL+.
-      #   Objects will be in addition destroyed if they're associated with <tt>dependent: :destroy</tt>,
-      #   and deleted if they're associated with <tt>dependent: :delete_all</tt>.
-      #
-      #   If the <tt>:through</tt> option is used, then the join records are deleted (rather than
-      #   nullified) by default, but you can specify <tt>dependent: :destroy</tt> or
-      #   <tt>dependent: :nullify</tt> to override this.
-      # [collection.destroy(object, ...)]
-      #   Removes one or more objects from the collection by running <tt>destroy</tt> on
-      #   each record, regardless of any dependent option, ensuring callbacks are run.
-      #
-      #   If the <tt>:through</tt> option is used, then the join records are destroyed
-      #   instead, not the objects themselves.
-      # [collection=objects]
-      #   Replaces the collections content by deleting and adding objects as appropriate. If the <tt>:through</tt>
-      #   option is true callbacks in the join models are triggered except destroy callbacks, since deletion is
-      #   direct by default. You can specify <tt>dependent: :destroy</tt> or
-      #   <tt>dependent: :nullify</tt> to override this.
-      # [collection_singular_ids]
-      #   Returns an array of the associated objects' ids
-      # [collection_singular_ids=ids]
-      #   Replace the collection with the objects identified by the primary keys in +ids+. This
-      #   method loads the models and calls <tt>collection=</tt>. See above.
-      # [collection.clear]
-      #   Removes every object from the collection. This destroys the associated objects if they
-      #   are associated with <tt>dependent: :destroy</tt>, deletes them directly from the
-      #   database if <tt>dependent: :delete_all</tt>, otherwise sets their foreign keys to +NULL+.
-      #   If the <tt>:through</tt> option is true no destroy callbacks are invoked on the join models.
-      #   Join models are directly deleted.
-      # [collection.empty?]
-      #   Returns +true+ if there are no associated objects.
-      # [collection.size]
-      #   Returns the number of associated objects.
-      # [collection.find(...)]
-      #   Finds an associated object according to the same rules as ActiveRecord::FinderMethods#find.
-      # [collection.exists?(...)]
-      #   Checks whether an associated object with the given conditions exists.
-      #   Uses the same rules as ActiveRecord::FinderMethods#exists?.
-      # [collection.build(attributes = {}, ...)]
-      #   Returns one or more new objects of the collection type that have been instantiated
-      #   with +attributes+ and linked to this object through a foreign key, but have not yet
-      #   been saved.
-      # [collection.create(attributes = {})]
-      #   Returns a new object of the collection type that has been instantiated
-      #   with +attributes+, linked to this object through a foreign key, and that has already
-      #   been saved (if it passed the validation). *Note*: This only works if the base model
-      #   already exists in the DB, not if it is a new (unsaved) record!
-      # [collection.create!(attributes = {})]
-      #   Does the same as <tt>collection.create</tt>, but raises ActiveRecord::RecordInvalid
-      #   if the record is invalid.
-      #
-      # === Example
-      #
-      # A <tt>Firm</tt> class declares <tt>has_many :clients</tt>, which will add:
-      # * <tt>Firm#clients</tt> (similar to <tt>Client.where(firm_id: id)</tt>)
-      # * <tt>Firm#clients<<</tt>
-      # * <tt>Firm#clients.delete</tt>
-      # * <tt>Firm#clients.destroy</tt>
-      # * <tt>Firm#clients=</tt>
-      # * <tt>Firm#client_ids</tt>
-      # * <tt>Firm#client_ids=</tt>
-      # * <tt>Firm#clients.clear</tt>
-      # * <tt>Firm#clients.empty?</tt> (similar to <tt>firm.clients.size == 0</tt>)
-      # * <tt>Firm#clients.size</tt> (similar to <tt>Client.count "firm_id = #{id}"</tt>)
-      # * <tt>Firm#clients.find</tt> (similar to <tt>Client.where(firm_id: id).find(id)</tt>)
-      # * <tt>Firm#clients.exists?(name: 'ACME')</tt> (similar to <tt>Client.exists?(name: 'ACME', firm_id: firm.id)</tt>)
-      # * <tt>Firm#clients.build</tt> (similar to <tt>Client.new("firm_id" => id)</tt>)
-      # * <tt>Firm#clients.create</tt> (similar to <tt>c = Client.new("firm_id" => id); c.save; c</tt>)
-      # * <tt>Firm#clients.create!</tt> (similar to <tt>c = Client.new("firm_id" => id); c.save!</tt>)
-      # The declaration can also include an +options+ hash to specialize the behavior of the association.
-      #
-      # === Scopes
-      #
-      # You can pass a second argument +scope+ as a callable (i.e. proc or
-      # lambda) to retrieve a specific set of records or customize the generated
-      # query when you access the associated collection.
-      #
-      # Scope examples:
-      #   has_many :comments, -> { where(author_id: 1) }
-      #   has_many :employees, -> { joins(:address) }
-      #   has_many :posts, ->(post) { where("max_post_length > ?", post.length) }
-      #
-      # === Extensions
-      #
-      # The +extension+ argument allows you to pass a block into a has_many
-      # association. This is useful for adding new finders, creators and other
-      # factory-type methods to be used as part of the association.
-      #
-      # Extension examples:
-      #   has_many :employees do
-      #     def find_or_create_by_name(name)
-      #       first_name, last_name = name.split(" ", 2)
-      #       find_or_create_by(first_name: first_name, last_name: last_name)
+      # \Associations are a set of macro-like class methods for tying objects together through
+      # foreign keys. They express relationships like "Project has one Project Manager"
+      # or "Project belongs to a Portfolio". Each macro adds a number of methods to the
+      # class which are specialized according to the collection or association symbol and the
+      # options hash. It works much the same way as Ruby's own <tt>attr*</tt>
+      # methods.
+      #
+      #   class Project < ActiveRecord::Base
+      #     belongs_to              :portfolio
+      #     has_one                 :project_manager
+      #     has_many                :milestones
+      #     has_and_belongs_to_many :categories
+      #   end
+      #
+      # The project class now has the following methods (and more) to ease the traversal and
+      # manipulation of its relationships:
+      # * <tt>Project#portfolio, Project#portfolio=(portfolio), Project#portfolio.nil?</tt>
+      # * <tt>Project#project_manager, Project#project_manager=(project_manager), Project#project_manager.nil?,</tt>
+      # * <tt>Project#milestones.empty?, Project#milestones.size, Project#milestones, Project#milestones<<(milestone),</tt>
+      #   <tt>Project#milestones.delete(milestone), Project#milestones.destroy(milestone), Project#milestones.find(milestone_id),</tt>
+      #   <tt>Project#milestones.build, Project#milestones.create</tt>
+      # * <tt>Project#categories.empty?, Project#categories.size, Project#categories, Project#categories<<(category1),</tt>
+      #   <tt>Project#categories.delete(category1), Project#categories.destroy(category1)</tt>
+      #
+      # === A word of warning
+      #
+      # Don't create associations that have the same name as {instance methods}[rdoc-ref:ActiveRecord::Core] of
+      # <tt>ActiveRecord::Base</tt>. Since the association adds a method with that name to
+      # its model, using an association with the same name as one provided by <tt>ActiveRecord::Base</tt> will override the method inherited through <tt>ActiveRecord::Base</tt> and will break things.
+      # For instance, +attributes+ and +connection+ would be bad choices for association names, because those names already exist in the list of <tt>ActiveRecord::Base</tt> instance methods.
+      #
+      # == Auto-generated methods
+      # See also Instance Public methods below for more details.
+      #
+      # === Singular associations (one-to-one)
+      #                                     |            |  belongs_to  |
+      #   generated methods                 | belongs_to | :polymorphic | has_one
+      #   ----------------------------------+------------+--------------+---------
+      #   other                             |     X      |      X       |    X
+      #   other=(other)                     |     X      |      X       |    X
+      #   build_other(attributes={})        |     X      |              |    X
+      #   create_other(attributes={})       |     X      |              |    X
+      #   create_other!(attributes={})      |     X      |              |    X
+      #   reload_other                      |     X      |      X       |    X
+      #
+      # === Collection associations (one-to-many / many-to-many)
+      #                                     |       |          | has_many
+      #   generated methods                 | habtm | has_many | :through
+      #   ----------------------------------+-------+----------+----------
+      #   others                            |   X   |    X     |    X
+      #   others=(other,other,...)          |   X   |    X     |    X
+      #   other_ids                         |   X   |    X     |    X
+      #   other_ids=(id,id,...)             |   X   |    X     |    X
+      #   others<<                          |   X   |    X     |    X
+      #   others.push                       |   X   |    X     |    X
+      #   others.concat                     |   X   |    X     |    X
+      #   others.build(attributes={})       |   X   |    X     |    X
+      #   others.create(attributes={})      |   X   |    X     |    X
+      #   others.create!(attributes={})     |   X   |    X     |    X
+      #   others.size                       |   X   |    X     |    X
+      #   others.length                     |   X   |    X     |    X
+      #   others.count                      |   X   |    X     |    X
+      #   others.sum(*args)                 |   X   |    X     |    X
+      #   others.empty?                     |   X   |    X     |    X
+      #   others.clear                      |   X   |    X     |    X
+      #   others.delete(other,other,...)    |   X   |    X     |    X
+      #   others.delete_all                 |   X   |    X     |    X
+      #   others.destroy(other,other,...)   |   X   |    X     |    X
+      #   others.destroy_all                |   X   |    X     |    X
+      #   others.find(*args)                |   X   |    X     |    X
+      #   others.exists?                    |   X   |    X     |    X
+      #   others.distinct                   |   X   |    X     |    X
+      #   others.reset                      |   X   |    X     |    X
+      #   others.reload                     |   X   |    X     |    X
+      #
+      # === Overriding generated methods
+      #
+      # Association methods are generated in a module included into the model
+      # class, making overrides easy. The original generated method can thus be
+      # called with +super+:
+      #
+      #   class Car < ActiveRecord::Base
+      #     belongs_to :owner
+      #     belongs_to :old_owner
+      #
+      #     def owner=(new_owner)
+      #       self.old_owner = self.owner
+      #       super
       #     end
       #   end
       #
-      # === Options
-      # [:class_name]
-      #   Specify the class name of the association. Use it only if that name can't be inferred
-      #   from the association name. So <tt>has_many :products</tt> will by default be linked
-      #   to the +Product+ class, but if the real class name is +SpecialProduct+, you'll have to
-      #   specify it with this option.
-      # [:foreign_key]
-      #   Specify the foreign key used for the association. By default this is guessed to be the name
-      #   of this class in lower-case and "_id" suffixed. So a Person class that makes a #has_many
-      #   association will use "person_id" as the default <tt>:foreign_key</tt>.
-      # [:foreign_type]
-      #   Specify the column used to store the associated object's type, if this is a polymorphic
-      #   association. By default this is guessed to be the name of the polymorphic association
-      #   specified on "as" option with a "_type" suffix. So a class that defines a
-      #   <tt>has_many :tags, as: :taggable</tt> association will use "taggable_type" as the
-      #   default <tt>:foreign_type</tt>.
-      # [:primary_key]
-      #   Specify the name of the column to use as the primary key for the association. By default this is +id+.
-      # [:dependent]
-      #   Controls what happens to the associated objects when
-      #   their owner is destroyed. Note that these are implemented as
-      #   callbacks, and Rails executes callbacks in order. Therefore, other
-      #   similar callbacks may affect the <tt>:dependent</tt> behavior, and the
-      #   <tt>:dependent</tt> behavior may affect other callbacks.
-      #
-      #   * <tt>:destroy</tt> causes all the associated objects to also be destroyed.
-      #   * <tt>:delete_all</tt> causes all the associated objects to be deleted directly from the database (so callbacks will not be executed).
-      #   * <tt>:nullify</tt> causes the foreign keys to be set to +NULL+. Callbacks are not executed.
-      #   * <tt>:restrict_with_exception</tt> causes an exception to be raised if there are any associated records.
-      #   * <tt>:restrict_with_error</tt> causes an error to be added to the owner if there are any associated objects.
-      #
-      #   If using with the <tt>:through</tt> option, the association on the join model must be
-      #   a #belongs_to, and the records which get deleted are the join records, rather than
-      #   the associated records.
-      # [:counter_cache]
-      #   This option can be used to configure a custom named <tt>:counter_cache.</tt> You only need this option,
-      #   when you customized the name of your <tt>:counter_cache</tt> on the #belongs_to association.
-      # [:as]
-      #   Specifies a polymorphic interface (See #belongs_to).
-      # [:through]
-      #   Specifies an association through which to perform the query. This can be any other type
-      #   of association, including other <tt>:through</tt> associations. Options for <tt>:class_name</tt>,
-      #   <tt>:primary_key</tt> and <tt>:foreign_key</tt> are ignored, as the association uses the
-      #   source reflection.
-      #
-      #   If the association on the join model is a #belongs_to, the collection can be modified
-      #   and the records on the <tt>:through</tt> model will be automatically created and removed
-      #   as appropriate. Otherwise, the collection is read-only, so you should manipulate the
-      #   <tt>:through</tt> association directly.
-      #
-      #   If you are going to modify the association (rather than just read from it), then it is
-      #   a good idea to set the <tt>:inverse_of</tt> option on the source association on the
-      #   join model. This allows associated records to be built which will automatically create
-      #   the appropriate join model records when they are saved. (See the 'Association Join Models'
-      #   section above.)
-      # [:source]
-      #   Specifies the source association name used by #has_many <tt>:through</tt> queries.
-      #   Only use it if the name cannot be inferred from the association.
-      #   <tt>has_many :subscribers, through: :subscriptions</tt> will look for either <tt>:subscribers</tt> or
-      #   <tt>:subscriber</tt> on Subscription, unless a <tt>:source</tt> is given.
-      # [:source_type]
-      #   Specifies type of the source association used by #has_many <tt>:through</tt> queries where the source
-      #   association is a polymorphic #belongs_to.
-      # [:validate]
-      #   When set to +true+, validates new objects added to association when saving the parent object. +true+ by default.
-      #   If you want to ensure associated objects are revalidated on every update, use +validates_associated+.
-      # [:autosave]
-      #   If true, always save the associated objects or destroy them if marked for destruction,
-      #   when saving the parent object. If false, never save or destroy the associated objects.
-      #   By default, only save associated objects that are new records. This option is implemented as a
-      #   +before_save+ callback. Because callbacks are run in the order they are defined, associated objects
-      #   may need to be explicitly saved in any user-defined +before_save+ callbacks.
-      #
-      #   Note that NestedAttributes::ClassMethods#accepts_nested_attributes_for sets
-      #   <tt>:autosave</tt> to <tt>true</tt>.
-      # [:inverse_of]
-      #   Specifies the name of the #belongs_to association on the associated object
-      #   that is the inverse of this #has_many association. Does not work in combination
-      #   with <tt>:through</tt> or <tt>:as</tt> options.
-      #   See ActiveRecord::Associations::ClassMethods's overview on Bi-directional associations for more detail.
-      # [:extend]
-      #   Specifies a module or array of modules that will be extended into the association object returned.
-      #   Useful for defining methods on associations, especially when they should be shared between multiple
-      #   association objects.
-      #
-      # Option examples:
-      #   has_many :comments, -> { order("posted_on") }
-      #   has_many :comments, -> { includes(:author) }
-      #   has_many :people, -> { where(deleted: false).order("name") }, class_name: "Person"
-      #   has_many :tracks, -> { order("position") }, dependent: :destroy
-      #   has_many :comments, dependent: :nullify
-      #   has_many :tags, as: :taggable
-      #   has_many :reports, -> { readonly }
-      #   has_many :subscribers, through: :subscriptions, source: :user
-      def has_many(name, scope = nil, options = {}, &extension)
-        reflection = Builder::HasMany.build(self, name, scope, options, &extension)
-        Reflection.add_reflection self, name, reflection
-      end
-
-      # Specifies a one-to-one association with another class. This method should only be used
-      # if the other class contains the foreign key. If the current class contains the foreign key,
-      # then you should use #belongs_to instead. See also ActiveRecord::Associations::ClassMethods's overview
-      # on when to use #has_one and when to use #belongs_to.
-      #
-      # The following methods for retrieval and query of a single associated object will be added:
-      #
-      # +association+ is a placeholder for the symbol passed as the +name+ argument, so
-      # <tt>has_one :manager</tt> would add among others <tt>manager.nil?</tt>.
-      #
-      # [association(force_reload = false)]
-      #   Returns the associated object. +nil+ is returned if none is found.
-      # [association=(associate)]
-      #   Assigns the associate object, extracts the primary key, sets it as the foreign key,
-      #   and saves the associate object. To avoid database inconsistencies, permanently deletes an existing
-      #   associated object when assigning a new one, even if the new one isn't saved to database.
-      # [build_association(attributes = {})]
-      #   Returns a new object of the associated type that has been instantiated
-      #   with +attributes+ and linked to this object through a foreign key, but has not
-      #   yet been saved.
-      # [create_association(attributes = {})]
-      #   Returns a new object of the associated type that has been instantiated
-      #   with +attributes+, linked to this object through a foreign key, and that
-      #   has already been saved (if it passed the validation).
-      # [create_association!(attributes = {})]
-      #   Does the same as <tt>create_association</tt>, but raises ActiveRecord::RecordInvalid
-      #   if the record is invalid.
-      #
-      # === Example
-      #
-      # An Account class declares <tt>has_one :beneficiary</tt>, which will add:
-      # * <tt>Account#beneficiary</tt> (similar to <tt>Beneficiary.where(account_id: id).first</tt>)
-      # * <tt>Account#beneficiary=(beneficiary)</tt> (similar to <tt>beneficiary.account_id = account.id; beneficiary.save</tt>)
-      # * <tt>Account#build_beneficiary</tt> (similar to <tt>Beneficiary.new("account_id" => id)</tt>)
-      # * <tt>Account#create_beneficiary</tt> (similar to <tt>b = Beneficiary.new("account_id" => id); b.save; b</tt>)
-      # * <tt>Account#create_beneficiary!</tt> (similar to <tt>b = Beneficiary.new("account_id" => id); b.save!; b</tt>)
-      #
-      # === Scopes
-      #
-      # You can pass a second argument +scope+ as a callable (i.e. proc or
-      # lambda) to retrieve a specific record or customize the generated query
-      # when you access the associated object.
-      #
-      # Scope examples:
-      #   has_one :author, -> { where(comment_id: 1) }
-      #   has_one :employer, -> { joins(:company) }
-      #   has_one :dob, ->(dob) { where("Date.new(2000, 01, 01) > ?", dob) }
-      #
-      # === Options
-      #
-      # The declaration can also include an +options+ hash to specialize the behavior of the association.
-      #
-      # Options are:
-      # [:class_name]
-      #   Specify the class name of the association. Use it only if that name can't be inferred
-      #   from the association name. So <tt>has_one :manager</tt> will by default be linked to the Manager class, but
-      #   if the real class name is Person, you'll have to specify it with this option.
-      # [:dependent]
-      #   Controls what happens to the associated object when
-      #   its owner is destroyed:
-      #
-      #   * <tt>:destroy</tt> causes the associated object to also be destroyed
-      #   * <tt>:delete</tt> causes the associated object to be deleted directly from the database (so callbacks will not execute)
-      #   * <tt>:nullify</tt> causes the foreign key to be set to +NULL+. Callbacks are not executed.
-      #   * <tt>:restrict_with_exception</tt> causes an exception to be raised if there is an associated record
-      #   * <tt>:restrict_with_error</tt> causes an error to be added to the owner if there is an associated object
-      #
-      #   Note that <tt>:dependent</tt> option is ignored when using <tt>:through</tt> option.
-      # [:foreign_key]
-      #   Specify the foreign key used for the association. By default this is guessed to be the name
-      #   of this class in lower-case and "_id" suffixed. So a Person class that makes a #has_one association
-      #   will use "person_id" as the default <tt>:foreign_key</tt>.
-      # [:foreign_type]
-      #   Specify the column used to store the associated object's type, if this is a polymorphic
-      #   association. By default this is guessed to be the name of the polymorphic association
-      #   specified on "as" option with a "_type" suffix. So a class that defines a
-      #   <tt>has_one :tag, as: :taggable</tt> association will use "taggable_type" as the
-      #   default <tt>:foreign_type</tt>.
-      # [:primary_key]
-      #   Specify the method that returns the primary key used for the association. By default this is +id+.
-      # [:as]
-      #   Specifies a polymorphic interface (See #belongs_to).
-      # [:through]
-      #   Specifies a Join Model through which to perform the query. Options for <tt>:class_name</tt>,
-      #   <tt>:primary_key</tt>, and <tt>:foreign_key</tt> are ignored, as the association uses the
-      #   source reflection. You can only use a <tt>:through</tt> query through a #has_one
-      #   or #belongs_to association on the join model.
-      # [:source]
-      #   Specifies the source association name used by #has_one <tt>:through</tt> queries.
-      #   Only use it if the name cannot be inferred from the association.
-      #   <tt>has_one :favorite, through: :favorites</tt> will look for a
-      #   <tt>:favorite</tt> on Favorite, unless a <tt>:source</tt> is given.
-      # [:source_type]
-      #   Specifies type of the source association used by #has_one <tt>:through</tt> queries where the source
-      #   association is a polymorphic #belongs_to.
-      # [:validate]
-      #   When set to +true+, validates new objects added to association when saving the parent object. +false+ by default.
-      #   If you want to ensure associated objects are revalidated on every update, use +validates_associated+.
-      # [:autosave]
-      #   If true, always save the associated object or destroy it if marked for destruction,
-      #   when saving the parent object. If false, never save or destroy the associated object.
-      #   By default, only save the associated object if it's a new record.
-      #
-      #   Note that NestedAttributes::ClassMethods#accepts_nested_attributes_for sets
-      #   <tt>:autosave</tt> to <tt>true</tt>.
-      # [:inverse_of]
-      #   Specifies the name of the #belongs_to association on the associated object
-      #   that is the inverse of this #has_one association. Does not work in combination
-      #   with <tt>:through</tt> or <tt>:as</tt> options.
-      #   See ActiveRecord::Associations::ClassMethods's overview on Bi-directional associations for more detail.
-      # [:required]
-      #   When set to +true+, the association will also have its presence validated.
-      #   This will validate the association itself, not the id. You can use
-      #   +:inverse_of+ to avoid an extra query during validation.
-      #
-      # Option examples:
-      #   has_one :credit_card, dependent: :destroy  # destroys the associated credit card
-      #   has_one :credit_card, dependent: :nullify  # updates the associated records foreign
-      #                                                 # key value to NULL rather than destroying it
-      #   has_one :last_comment, -> { order('posted_on') }, class_name: "Comment"
-      #   has_one :project_manager, -> { where(role: 'project_manager') }, class_name: "Person"
-      #   has_one :attachment, as: :attachable
-      #   has_one :boss, -> { readonly }
-      #   has_one :club, through: :membership
-      #   has_one :primary_address, -> { where(primary: true) }, through: :addressables, source: :addressable
-      #   has_one :credit_card, required: true
-      def has_one(name, scope = nil, options = {})
-        reflection = Builder::HasOne.build(self, name, scope, options)
-        Reflection.add_reflection self, name, reflection
-      end
-
-      # Specifies a one-to-one association with another class. This method should only be used
-      # if this class contains the foreign key. If the other class contains the foreign key,
-      # then you should use #has_one instead. See also ActiveRecord::Associations::ClassMethods's overview
-      # on when to use #has_one and when to use #belongs_to.
-      #
-      # Methods will be added for retrieval and query for a single associated object, for which
-      # this object holds an id:
-      #
-      # +association+ is a placeholder for the symbol passed as the +name+ argument, so
-      # <tt>belongs_to :author</tt> would add among others <tt>author.nil?</tt>.
-      #
-      # [association(force_reload = false)]
-      #   Returns the associated object. +nil+ is returned if none is found.
-      # [association=(associate)]
-      #   Assigns the associate object, extracts the primary key, and sets it as the foreign key.
-      # [build_association(attributes = {})]
-      #   Returns a new object of the associated type that has been instantiated
-      #   with +attributes+ and linked to this object through a foreign key, but has not yet been saved.
-      # [create_association(attributes = {})]
-      #   Returns a new object of the associated type that has been instantiated
-      #   with +attributes+, linked to this object through a foreign key, and that
-      #   has already been saved (if it passed the validation).
-      # [create_association!(attributes = {})]
-      #   Does the same as <tt>create_association</tt>, but raises ActiveRecord::RecordInvalid
-      #   if the record is invalid.
-      #
-      # === Example
-      #
-      # A Post class declares <tt>belongs_to :author</tt>, which will add:
-      # * <tt>Post#author</tt> (similar to <tt>Author.find(author_id)</tt>)
-      # * <tt>Post#author=(author)</tt> (similar to <tt>post.author_id = author.id</tt>)
-      # * <tt>Post#build_author</tt> (similar to <tt>post.author = Author.new</tt>)
-      # * <tt>Post#create_author</tt> (similar to <tt>post.author = Author.new; post.author.save; post.author</tt>)
-      # * <tt>Post#create_author!</tt> (similar to <tt>post.author = Author.new; post.author.save!; post.author</tt>)
-      # The declaration can also include an +options+ hash to specialize the behavior of the association.
-      #
-      # === Scopes
-      #
-      # You can pass a second argument +scope+ as a callable (i.e. proc or
-      # lambda) to retrieve a specific record or customize the generated query
-      # when you access the associated object.
-      #
-      # Scope examples:
-      #   belongs_to :firm, -> { where(id: 2) }
-      #   belongs_to :user, -> { joins(:friends) }
-      #   belongs_to :level, ->(level) { where("game_level > ?", level.current) }
-      #
-      # === Options
-      #
-      # [:class_name]
-      #   Specify the class name of the association. Use it only if that name can't be inferred
-      #   from the association name. So <tt>belongs_to :author</tt> will by default be linked to the Author class, but
-      #   if the real class name is Person, you'll have to specify it with this option.
-      # [:foreign_key]
-      #   Specify the foreign key used for the association. By default this is guessed to be the name
-      #   of the association with an "_id" suffix. So a class that defines a <tt>belongs_to :person</tt>
-      #   association will use "person_id" as the default <tt>:foreign_key</tt>. Similarly,
-      #   <tt>belongs_to :favorite_person, class_name: "Person"</tt> will use a foreign key
-      #   of "favorite_person_id".
-      # [:foreign_type]
-      #   Specify the column used to store the associated object's type, if this is a polymorphic
-      #   association. By default this is guessed to be the name of the association with a "_type"
-      #   suffix. So a class that defines a <tt>belongs_to :taggable, polymorphic: true</tt>
-      #   association will use "taggable_type" as the default <tt>:foreign_type</tt>.
-      # [:primary_key]
-      #   Specify the method that returns the primary key of associated object used for the association.
-      #   By default this is id.
-      # [:dependent]
-      #   If set to <tt>:destroy</tt>, the associated object is destroyed when this object is. If set to
-      #   <tt>:delete</tt>, the associated object is deleted *without* calling its destroy method.
-      #   This option should not be specified when #belongs_to is used in conjunction with
-      #   a #has_many relationship on another class because of the potential to leave
-      #   orphaned records behind.
-      # [:counter_cache]
-      #   Caches the number of belonging objects on the associate class through the use of CounterCache::ClassMethods#increment_counter
-      #   and CounterCache::ClassMethods#decrement_counter. The counter cache is incremented when an object of this
-      #   class is created and decremented when it's destroyed. This requires that a column
-      #   named <tt>#{table_name}_count</tt> (such as +comments_count+ for a belonging Comment class)
-      #   is used on the associate class (such as a Post class) - that is the migration for
-      #   <tt>#{table_name}_count</tt> is created on the associate class (such that <tt>Post.comments_count</tt> will
-      #   return the count cached, see note below). You can also specify a custom counter
-      #   cache column by providing a column name instead of a +true+/+false+ value to this
-      #   option (e.g., <tt>counter_cache: :my_custom_counter</tt>.)
-      #   Note: Specifying a counter cache will add it to that model's list of readonly attributes
-      #   using +attr_readonly+.
-      # [:polymorphic]
-      #   Specify this association is a polymorphic association by passing +true+.
-      #   Note: If you've enabled the counter cache, then you may want to add the counter cache attribute
-      #   to the +attr_readonly+ list in the associated classes (e.g. <tt>class Post; attr_readonly :comments_count; end</tt>).
-      # [:validate]
-      #   When set to +true+, validates new objects added to association when saving the parent object. +false+ by default.
-      #   If you want to ensure associated objects are revalidated on every update, use +validates_associated+.
-      # [:autosave]
-      #   If true, always save the associated object or destroy it if marked for destruction, when
-      #   saving the parent object.
-      #   If false, never save or destroy the associated object.
-      #   By default, only save the associated object if it's a new record.
-      #
-      #   Note that NestedAttributes::ClassMethods#accepts_nested_attributes_for
-      #   sets <tt>:autosave</tt> to <tt>true</tt>.
-      # [:touch]
-      #   If true, the associated object will be touched (the updated_at/on attributes set to current time)
-      #   when this record is either saved or destroyed. If you specify a symbol, that attribute
-      #   will be updated with the current time in addition to the updated_at/on attribute.
-      #   Please note that with touching no validation is performed and only the +after_touch+,
-      #   +after_commit+ and +after_rollback+ callbacks are executed.
-      # [:inverse_of]
-      #   Specifies the name of the #has_one or #has_many association on the associated
-      #   object that is the inverse of this #belongs_to association. Does not work in
-      #   combination with the <tt>:polymorphic</tt> options.
-      #   See ActiveRecord::Associations::ClassMethods's overview on Bi-directional associations for more detail.
-      # [:optional]
-      #   When set to +true+, the association will not have its presence validated.
-      # [:required]
-      #   When set to +true+, the association will also have its presence validated.
-      #   This will validate the association itself, not the id. You can use
-      #   +:inverse_of+ to avoid an extra query during validation.
-      #   NOTE: <tt>required</tt> is set to <tt>true</tt> by default and is deprecated. If
-      #   you don't want to have association presence validated, use <tt>optional: true</tt>.
-      #
-      # Option examples:
-      #   belongs_to :firm, foreign_key: "client_of"
-      #   belongs_to :person, primary_key: "name", foreign_key: "person_name"
-      #   belongs_to :author, class_name: "Person", foreign_key: "author_id"
-      #   belongs_to :valid_coupon, ->(o) { where "discounts > ?", o.payments_count },
-      #                             class_name: "Coupon", foreign_key: "coupon_id"
-      #   belongs_to :attachable, polymorphic: true
-      #   belongs_to :project, -> { readonly }
-      #   belongs_to :post, counter_cache: true
-      #   belongs_to :comment, touch: true
-      #   belongs_to :company, touch: :employees_last_updated_at
-      #   belongs_to :user, optional: true
-      def belongs_to(name, scope = nil, options = {})
-        reflection = Builder::BelongsTo.build(self, name, scope, options)
-        Reflection.add_reflection self, name, reflection
-      end
-
-      # Specifies a many-to-many relationship with another class. This associates two classes via an
-      # intermediate join table. Unless the join table is explicitly specified as an option, it is
-      # guessed using the lexical order of the class names. So a join between Developer and Project
-      # will give the default join table name of "developers_projects" because "D" precedes "P" alphabetically.
-      # Note that this precedence is calculated using the <tt><</tt> operator for String. This
-      # means that if the strings are of different lengths, and the strings are equal when compared
-      # up to the shortest length, then the longer string is considered of higher
-      # lexical precedence than the shorter one. For example, one would expect the tables "paper_boxes" and "papers"
-      # to generate a join table name of "papers_paper_boxes" because of the length of the name "paper_boxes",
-      # but it in fact generates a join table name of "paper_boxes_papers". Be aware of this caveat, and use the
-      # custom <tt>:join_table</tt> option if you need to.
-      # If your tables share a common prefix, it will only appear once at the beginning. For example,
-      # the tables "catalog_categories" and "catalog_products" generate a join table name of "catalog_categories_products".
-      #
-      # The join table should not have a primary key or a model associated with it. You must manually generate the
-      # join table with a migration such as this:
-      #
-      #   class CreateDevelopersProjectsJoinTable < ActiveRecord::Migration[5.0]
-      #     def change
-      #       create_join_table :developers, :projects
+      # The association methods module is included immediately after the
+      # generated attributes methods module, meaning an association will
+      # override the methods for an attribute with the same name.
+      #
+      # == Cardinality and associations
+      #
+      # Active Record associations can be used to describe one-to-one, one-to-many and many-to-many
+      # relationships between models. Each model uses an association to describe its role in
+      # the relation. The #belongs_to association is always used in the model that has
+      # the foreign key.
+      #
+      # === One-to-one
+      #
+      # Use #has_one in the base, and #belongs_to in the associated model.
+      #
+      #   class Employee < ActiveRecord::Base
+      #     has_one :office
+      #   end
+      #   class Office < ActiveRecord::Base
+      #     belongs_to :employee    # foreign key - employee_id
+      #   end
+      #
+      # === One-to-many
+      #
+      # Use #has_many in the base, and #belongs_to in the associated model.
+      #
+      #   class Manager < ActiveRecord::Base
+      #     has_many :employees
+      #   end
+      #   class Employee < ActiveRecord::Base
+      #     belongs_to :manager     # foreign key - manager_id
+      #   end
+      #
+      # === Many-to-many
+      #
+      # There are two ways to build a many-to-many relationship.
+      #
+      # The first way uses a #has_many association with the <tt>:through</tt> option and a join model, so
+      # there are two stages of associations.
+      #
+      #   class Assignment < ActiveRecord::Base
+      #     belongs_to :programmer  # foreign key - programmer_id
+      #     belongs_to :project     # foreign key - project_id
+      #   end
+      #   class Programmer < ActiveRecord::Base
+      #     has_many :assignments
+      #     has_many :projects, through: :assignments
+      #   end
+      #   class Project < ActiveRecord::Base
+      #     has_many :assignments
+      #     has_many :programmers, through: :assignments
+      #   end
+      #
+      # For the second way, use #has_and_belongs_to_many in both models. This requires a join table
+      # that has no corresponding model or primary key.
+      #
+      #   class Programmer < ActiveRecord::Base
+      #     has_and_belongs_to_many :projects       # foreign keys in the join table
+      #   end
+      #   class Project < ActiveRecord::Base
+      #     has_and_belongs_to_many :programmers    # foreign keys in the join table
+      #   end
+      #
+      # Choosing which way to build a many-to-many relationship is not always simple.
+      # If you need to work with the relationship model as its own entity,
+      # use #has_many <tt>:through</tt>. Use #has_and_belongs_to_many when working with legacy schemas or when
+      # you never work directly with the relationship itself.
+      #
+      # == Is it a #belongs_to or #has_one association?
+      #
+      # Both express a 1-1 relationship. The difference is mostly where to place the foreign
+      # key, which goes on the table for the class declaring the #belongs_to relationship.
+      #
+      #   class User < ActiveRecord::Base
+      #     # I reference an account.
+      #     belongs_to :account
+      #   end
+      #
+      #   class Account < ActiveRecord::Base
+      #     # One user references me.
+      #     has_one :user
+      #   end
+      #
+      # The tables for these classes could look something like:
+      #
+      #   CREATE TABLE users (
+      #     id bigint NOT NULL auto_increment,
+      #     account_id bigint default NULL,
+      #     name varchar default NULL,
+      #     PRIMARY KEY  (id)
+      #   )
+      #
+      #   CREATE TABLE accounts (
+      #     id bigint NOT NULL auto_increment,
+      #     name varchar default NULL,
+      #     PRIMARY KEY  (id)
+      #   )
+      #
+      # == Unsaved objects and associations
+      #
+      # You can manipulate objects and associations before they are saved to the database, but
+      # there is some special behavior you should be aware of, mostly involving the saving of
+      # associated objects.
+      #
+      # You can set the <tt>:autosave</tt> option on a #has_one, #belongs_to,
+      # #has_many, or #has_and_belongs_to_many association. Setting it
+      # to +true+ will _always_ save the members, whereas setting it to +false+ will
+      # _never_ save the members. More details about <tt>:autosave</tt> option is available at
+      # AutosaveAssociation.
+      #
+      # === One-to-one associations
+      #
+      # * Assigning an object to a #has_one association automatically saves that object and
+      #   the object being replaced (if there is one), in order to update their foreign
+      #   keys - except if the parent object is unsaved (<tt>new_record? == true</tt>).
+      # * If either of these saves fail (due to one of the objects being invalid), an
+      #   ActiveRecord::RecordNotSaved exception is raised and the assignment is
+      #   cancelled.
+      # * If you wish to assign an object to a #has_one association without saving it,
+      #   use the <tt>#build_association</tt> method (documented below). The object being
+      #   replaced will still be saved to update its foreign key.
+      # * Assigning an object to a #belongs_to association does not save the object, since
+      #   the foreign key field belongs on the parent. It does not save the parent either.
+      #
+      # === Collections
+      #
+      # * Adding an object to a collection (#has_many or #has_and_belongs_to_many) automatically
+      #   saves that object, except if the parent object (the owner of the collection) is not yet
+      #   stored in the database.
+      # * If saving any of the objects being added to a collection (via <tt>push</tt> or similar)
+      #   fails, then <tt>push</tt> returns +false+.
+      # * If saving fails while replacing the collection (via <tt>association=</tt>), an
+      #   ActiveRecord::RecordNotSaved exception is raised and the assignment is
+      #   cancelled.
+      # * You can add an object to a collection without automatically saving it by using the
+      #   <tt>collection.build</tt> method (documented below).
+      # * All unsaved (<tt>new_record? == true</tt>) members of the collection are automatically
+      #   saved when the parent is saved.
+      #
+      # == Customizing the query
+      #
+      # \Associations are built from <tt>Relation</tt> objects, and you can use the Relation syntax
+      # to customize them. For example, to add a condition:
+      #
+      #   class Blog < ActiveRecord::Base
+      #     has_many :published_posts, -> { where(published: true) }, class_name: 'Post'
+      #   end
+      #
+      # Inside the <tt>-> { ... }</tt> block you can use all of the usual Relation methods.
+      #
+      # === Accessing the owner object
+      #
+      # Sometimes it is useful to have access to the owner object when building the query. The owner
+      # is passed as a parameter to the block. For example, the following association would find all
+      # events that occur on the user's birthday:
+      #
+      #   class User < ActiveRecord::Base
+      #     has_many :birthday_events, ->(user) { where(starts_on: user.birthday) }, class_name: 'Event'
+      #   end
+      #
+      # Note: Joining, eager loading and preloading of these associations is not possible.
+      # These operations happen before instance creation and the scope will be called with a +nil+ argument.
+      #
+      # == Association callbacks
+      #
+      # Similar to the normal callbacks that hook into the life cycle of an Active Record object,
+      # you can also define callbacks that get triggered when you add an object to or remove an
+      # object from an association collection.
+      #
+      #   class Project
+      #     has_and_belongs_to_many :developers, after_add: :evaluate_velocity
+      #
+      #     def evaluate_velocity(developer)
+      #       ...
+      #     end
+      #   end
+      #
+      # It's possible to stack callbacks by passing them as an array. Example:
+      #
+      #   class Project
+      #     has_and_belongs_to_many :developers,
+      #                             after_add: [:evaluate_velocity, Proc.new { |p, d| p.shipping_date = Time.now}]
+      #   end
+      #
+      # Possible callbacks are: +before_add+, +after_add+, +before_remove+ and +after_remove+.
+      #
+      # If any of the +before_add+ callbacks throw an exception, the object will not be
+      # added to the collection.
+      #
+      # Similarly, if any of the +before_remove+ callbacks throw an exception, the object
+      # will not be removed from the collection.
+      #
+      # == Association extensions
+      #
+      # The proxy objects that control the access to associations can be extended through anonymous
+      # modules. This is especially beneficial for adding new finders, creators, and other
+      # factory-type methods that are only used as part of this association.
+      #
+      #   class Account < ActiveRecord::Base
+      #     has_many :people do
+      #       def find_or_create_by_name(name)
+      #         first_name, last_name = name.split(" ", 2)
+      #         find_or_create_by(first_name: first_name, last_name: last_name)
+      #       end
       #     end
       #   end
       #
-      # It's also a good idea to add indexes to each of those columns to speed up the joins process.
-      # However, in MySQL it is advised to add a compound index for both of the columns as MySQL only
-      # uses one index per table during the lookup.
-      #
-      # Adds the following methods for retrieval and query:
-      #
-      # +collection+ is a placeholder for the symbol passed as the +name+ argument, so
-      # <tt>has_and_belongs_to_many :categories</tt> would add among others <tt>categories.empty?</tt>.
-      #
-      # [collection(force_reload = false)]
-      #   Returns an array of all the associated objects.
-      #   An empty array is returned if none are found.
-      # [collection<<(object, ...)]
-      #   Adds one or more objects to the collection by creating associations in the join table
-      #   (<tt>collection.push</tt> and <tt>collection.concat</tt> are aliases to this method).
-      #   Note that this operation instantly fires update SQL without waiting for the save or update call on the
-      #   parent object, unless the parent object is a new record.
-      # [collection.delete(object, ...)]
-      #   Removes one or more objects from the collection by removing their associations from the join table.
-      #   This does not destroy the objects.
-      # [collection.destroy(object, ...)]
-      #   Removes one or more objects from the collection by running destroy on each association in the join table, overriding any dependent option.
-      #   This does not destroy the objects.
-      # [collection=objects]
-      #   Replaces the collection's content by deleting and adding objects as appropriate.
-      # [collection_singular_ids]
-      #   Returns an array of the associated objects' ids.
-      # [collection_singular_ids=ids]
-      #   Replace the collection by the objects identified by the primary keys in +ids+.
-      # [collection.clear]
-      #   Removes every object from the collection. This does not destroy the objects.
-      # [collection.empty?]
-      #   Returns +true+ if there are no associated objects.
-      # [collection.size]
-      #   Returns the number of associated objects.
-      # [collection.find(id)]
-      #   Finds an associated object responding to the +id+ and that
-      #   meets the condition that it has to be associated with this object.
-      #   Uses the same rules as ActiveRecord::FinderMethods#find.
-      # [collection.exists?(...)]
-      #   Checks whether an associated object with the given conditions exists.
-      #   Uses the same rules as ActiveRecord::FinderMethods#exists?.
-      # [collection.build(attributes = {})]
-      #   Returns a new object of the collection type that has been instantiated
-      #   with +attributes+ and linked to this object through the join table, but has not yet been saved.
-      # [collection.create(attributes = {})]
-      #   Returns a new object of the collection type that has been instantiated
-      #   with +attributes+, linked to this object through the join table, and that has already been
-      #   saved (if it passed the validation).
-      #
-      # === Example
-      #
-      # A Developer class declares <tt>has_and_belongs_to_many :projects</tt>, which will add:
-      # * <tt>Developer#projects</tt>
-      # * <tt>Developer#projects<<</tt>
-      # * <tt>Developer#projects.delete</tt>
-      # * <tt>Developer#projects.destroy</tt>
-      # * <tt>Developer#projects=</tt>
-      # * <tt>Developer#project_ids</tt>
-      # * <tt>Developer#project_ids=</tt>
-      # * <tt>Developer#projects.clear</tt>
-      # * <tt>Developer#projects.empty?</tt>
-      # * <tt>Developer#projects.size</tt>
-      # * <tt>Developer#projects.find(id)</tt>
-      # * <tt>Developer#projects.exists?(...)</tt>
-      # * <tt>Developer#projects.build</tt> (similar to <tt>Project.new("developer_id" => id)</tt>)
-      # * <tt>Developer#projects.create</tt> (similar to <tt>c = Project.new("developer_id" => id); c.save; c</tt>)
-      # The declaration may include an +options+ hash to specialize the behavior of the association.
-      #
-      # === Scopes
-      #
-      # You can pass a second argument +scope+ as a callable (i.e. proc or
-      # lambda) to retrieve a specific set of records or customize the generated
-      # query when you access the associated collection.
-      #
-      # Scope examples:
-      #   has_and_belongs_to_many :projects, -> { includes(:milestones, :manager) }
-      #   has_and_belongs_to_many :categories, ->(category) {
-      #     where("default_category = ?", category.name)
-      #   }
-      #
-      # === Extensions
-      #
-      # The +extension+ argument allows you to pass a block into a
-      # has_and_belongs_to_many association. This is useful for adding new
-      # finders, creators and other factory-type methods to be used as part of
-      # the association.
-      #
-      # Extension examples:
-      #   has_and_belongs_to_many :contractors do
+      #   person = Account.first.people.find_or_create_by_name("David Heinemeier Hansson")
+      #   person.first_name # => "David"
+      #   person.last_name  # => "Heinemeier Hansson"
+      #
+      # If you need to share the same extensions between many associations, you can use a named
+      # extension module.
+      #
+      #   module FindOrCreateByNameExtension
       #     def find_or_create_by_name(name)
       #       first_name, last_name = name.split(" ", 2)
       #       find_or_create_by(first_name: first_name, last_name: last_name)
       #     end
       #   end
       #
-      # === Options
-      #
-      # [:class_name]
-      #   Specify the class name of the association. Use it only if that name can't be inferred
-      #   from the association name. So <tt>has_and_belongs_to_many :projects</tt> will by default be linked to the
-      #   Project class, but if the real class name is SuperProject, you'll have to specify it with this option.
-      # [:join_table]
-      #   Specify the name of the join table if the default based on lexical order isn't what you want.
-      #   <b>WARNING:</b> If you're overwriting the table name of either class, the +table_name+ method
-      #   MUST be declared underneath any #has_and_belongs_to_many declaration in order to work.
-      # [:foreign_key]
-      #   Specify the foreign key used for the association. By default this is guessed to be the name
-      #   of this class in lower-case and "_id" suffixed. So a Person class that makes
-      #   a #has_and_belongs_to_many association to Project will use "person_id" as the
-      #   default <tt>:foreign_key</tt>.
-      # [:association_foreign_key]
-      #   Specify the foreign key used for the association on the receiving side of the association.
-      #   By default this is guessed to be the name of the associated class in lower-case and "_id" suffixed.
-      #   So if a Person class makes a #has_and_belongs_to_many association to Project,
-      #   the association will use "project_id" as the default <tt>:association_foreign_key</tt>.
-      # [:validate]
-      #   When set to +true+, validates new objects added to association when saving the parent object. +true+ by default.
-      #   If you want to ensure associated objects are revalidated on every update, use +validates_associated+.
-      # [:autosave]
-      #   If true, always save the associated objects or destroy them if marked for destruction, when
-      #   saving the parent object.
-      #   If false, never save or destroy the associated objects.
-      #   By default, only save associated objects that are new records.
-      #
-      #   Note that NestedAttributes::ClassMethods#accepts_nested_attributes_for sets
-      #   <tt>:autosave</tt> to <tt>true</tt>.
-      #
-      # Option examples:
-      #   has_and_belongs_to_many :projects
-      #   has_and_belongs_to_many :projects, -> { includes(:milestones, :manager) }
-      #   has_and_belongs_to_many :nations, class_name: "Country"
-      #   has_and_belongs_to_many :categories, join_table: "prods_cats"
-      #   has_and_belongs_to_many :categories, -> { readonly }
-      def has_and_belongs_to_many(name, scope = nil, options = {}, &extension)
-        if scope.is_a?(Hash)
-          options = scope
-          scope   = nil
+      #   class Account < ActiveRecord::Base
+      #     has_many :people, -> { extending FindOrCreateByNameExtension }
+      #   end
+      #
+      #   class Company < ActiveRecord::Base
+      #     has_many :people, -> { extending FindOrCreateByNameExtension }
+      #   end
+      #
+      # Some extensions can only be made to work with knowledge of the association's internals.
+      # Extensions can access relevant state using the following methods (where +items+ is the
+      # name of the association):
+      #
+      # * <tt>record.association(:items).owner</tt> - Returns the object the association is part of.
+      # * <tt>record.association(:items).reflection</tt> - Returns the reflection object that describes the association.
+      # * <tt>record.association(:items).target</tt> - Returns the associated object for #belongs_to and #has_one, or
+      #   the collection of associated objects for #has_many and #has_and_belongs_to_many.
+      #
+      # However, inside the actual extension code, you will not have access to the <tt>record</tt> as
+      # above. In this case, you can access <tt>proxy_association</tt>. For example,
+      # <tt>record.association(:items)</tt> and <tt>record.items.proxy_association</tt> will return
+      # the same object, allowing you to make calls like <tt>proxy_association.owner</tt> inside
+      # association extensions.
+      #
+      # == Association Join Models
+      #
+      # Has Many associations can be configured with the <tt>:through</tt> option to use an
+      # explicit join model to retrieve the data. This operates similarly to a
+      # #has_and_belongs_to_many association. The advantage is that you're able to add validations,
+      # callbacks, and extra attributes on the join model. Consider the following schema:
+      #
+      #   class Author < ActiveRecord::Base
+      #     has_many :authorships
+      #     has_many :books, through: :authorships
+      #   end
+      #
+      #   class Authorship < ActiveRecord::Base
+      #     belongs_to :author
+      #     belongs_to :book
+      #   end
+      #
+      #   @author = Author.first
+      #   @author.authorships.collect { |a| a.book } # selects all books that the author's authorships belong to
+      #   @author.books                              # selects all books by using the Authorship join model
+      #
+      # You can also go through a #has_many association on the join model:
+      #
+      #   class Firm < ActiveRecord::Base
+      #     has_many   :clients
+      #     has_many   :invoices, through: :clients
+      #   end
+      #
+      #   class Client < ActiveRecord::Base
+      #     belongs_to :firm
+      #     has_many   :invoices
+      #   end
+      #
+      #   class Invoice < ActiveRecord::Base
+      #     belongs_to :client
+      #   end
+      #
+      #   @firm = Firm.first
+      #   @firm.clients.flat_map { |c| c.invoices } # select all invoices for all clients of the firm
+      #   @firm.invoices                            # selects all invoices by going through the Client join model
+      #
+      # Similarly you can go through a #has_one association on the join model:
+      #
+      #   class Group < ActiveRecord::Base
+      #     has_many   :users
+      #     has_many   :avatars, through: :users
+      #   end
+      #
+      #   class User < ActiveRecord::Base
+      #     belongs_to :group
+      #     has_one    :avatar
+      #   end
+      #
+      #   class Avatar < ActiveRecord::Base
+      #     belongs_to :user
+      #   end
+      #
+      #   @group = Group.first
+      #   @group.users.collect { |u| u.avatar }.compact # select all avatars for all users in the group
+      #   @group.avatars                                # selects all avatars by going through the User join model.
+      #
+      # An important caveat with going through #has_one or #has_many associations on the
+      # join model is that these associations are *read-only*. For example, the following
+      # would not work following the previous example:
+      #
+      #   @group.avatars << Avatar.new   # this would work if User belonged_to Avatar rather than the other way around
+      #   @group.avatars.delete(@group.avatars.last)  # so would this
+      #
+      # == Setting Inverses
+      #
+      # If you are using a #belongs_to on the join model, it is a good idea to set the
+      # <tt>:inverse_of</tt> option on the #belongs_to, which will mean that the following example
+      # works correctly (where <tt>tags</tt> is a #has_many <tt>:through</tt> association):
+      #
+      #   @post = Post.first
+      #   @tag = @post.tags.build name: "ruby"
+      #   @tag.save
+      #
+      # The last line ought to save the through record (a <tt>Tagging</tt>). This will only work if the
+      # <tt>:inverse_of</tt> is set:
+      #
+      #   class Tagging < ActiveRecord::Base
+      #     belongs_to :post
+      #     belongs_to :tag, inverse_of: :taggings
+      #   end
+      #
+      # If you do not set the <tt>:inverse_of</tt> record, the association will
+      # do its best to match itself up with the correct inverse. Automatic
+      # inverse detection only works on #has_many, #has_one, and
+      # #belongs_to associations.
+      #
+      # Extra options on the associations, as defined in the
+      # <tt>AssociationReflection::INVALID_AUTOMATIC_INVERSE_OPTIONS</tt> constant, will
+      # also prevent the association's inverse from being found automatically.
+      #
+      # The automatic guessing of the inverse association uses a heuristic based
+      # on the name of the class, so it may not work for all associations,
+      # especially the ones with non-standard names.
+      #
+      # You can turn off the automatic detection of inverse associations by setting
+      # the <tt>:inverse_of</tt> option to <tt>false</tt> like so:
+      #
+      #   class Tagging < ActiveRecord::Base
+      #     belongs_to :tag, inverse_of: false
+      #   end
+      #
+      # == Nested \Associations
+      #
+      # You can actually specify *any* association with the <tt>:through</tt> option, including an
+      # association which has a <tt>:through</tt> option itself. For example:
+      #
+      #   class Author < ActiveRecord::Base
+      #     has_many :posts
+      #     has_many :comments, through: :posts
+      #     has_many :commenters, through: :comments
+      #   end
+      #
+      #   class Post < ActiveRecord::Base
+      #     has_many :comments
+      #   end
+      #
+      #   class Comment < ActiveRecord::Base
+      #     belongs_to :commenter
+      #   end
+      #
+      #   @author = Author.first
+      #   @author.commenters # => People who commented on posts written by the author
+      #
+      # An equivalent way of setting up this association this would be:
+      #
+      #   class Author < ActiveRecord::Base
+      #     has_many :posts
+      #     has_many :commenters, through: :posts
+      #   end
+      #
+      #   class Post < ActiveRecord::Base
+      #     has_many :comments
+      #     has_many :commenters, through: :comments
+      #   end
+      #
+      #   class Comment < ActiveRecord::Base
+      #     belongs_to :commenter
+      #   end
+      #
+      # When using a nested association, you will not be able to modify the association because there
+      # is not enough information to know what modification to make. For example, if you tried to
+      # add a <tt>Commenter</tt> in the example above, there would be no way to tell how to set up the
+      # intermediate <tt>Post</tt> and <tt>Comment</tt> objects.
+      #
+      # == Polymorphic \Associations
+      #
+      # Polymorphic associations on models are not restricted on what types of models they
+      # can be associated with. Rather, they specify an interface that a #has_many association
+      # must adhere to.
+      #
+      #   class Asset < ActiveRecord::Base
+      #     belongs_to :attachable, polymorphic: true
+      #   end
+      #
+      #   class Post < ActiveRecord::Base
+      #     has_many :assets, as: :attachable         # The :as option specifies the polymorphic interface to use.
+      #   end
+      #
+      #   @asset.attachable = @post
+      #
+      # This works by using a type column in addition to a foreign key to specify the associated
+      # record. In the Asset example, you'd need an +attachable_id+ integer column and an
+      # +attachable_type+ string column.
+      #
+      # Using polymorphic associations in combination with single table inheritance (STI) is
+      # a little tricky. In order for the associations to work as expected, ensure that you
+      # store the base model for the STI models in the type column of the polymorphic
+      # association. To continue with the asset example above, suppose there are guest posts
+      # and member posts that use the posts table for STI. In this case, there must be a +type+
+      # column in the posts table.
+      #
+      # Note: The <tt>attachable_type=</tt> method is being called when assigning an +attachable+.
+      # The +class_name+ of the +attachable+ is passed as a String.
+      #
+      #   class Asset < ActiveRecord::Base
+      #     belongs_to :attachable, polymorphic: true
+      #
+      #     def attachable_type=(class_name)
+      #        super(class_name.constantize.base_class.to_s)
+      #     end
+      #   end
+      #
+      #   class Post < ActiveRecord::Base
+      #     # because we store "Post" in attachable_type now dependent: :destroy will work
+      #     has_many :assets, as: :attachable, dependent: :destroy
+      #   end
+      #
+      #   class GuestPost < Post
+      #   end
+      #
+      #   class MemberPost < Post
+      #   end
+      #
+      # == Caching
+      #
+      # All of the methods are built on a simple caching principle that will keep the result
+      # of the last query around unless specifically instructed not to. The cache is even
+      # shared across methods to make it even cheaper to use the macro-added methods without
+      # worrying too much about performance at the first go.
+      #
+      #   project.milestones             # fetches milestones from the database
+      #   project.milestones.size        # uses the milestone cache
+      #   project.milestones.empty?      # uses the milestone cache
+      #   project.milestones.reload.size # fetches milestones from the database
+      #   project.milestones             # uses the milestone cache
+      #
+      # == Eager loading of associations
+      #
+      # Eager loading is a way to find objects of a certain class and a number of named associations.
+      # It is one of the easiest ways to prevent the dreaded N+1 problem in which fetching 100
+      # posts that each need to display their author triggers 101 database queries. Through the
+      # use of eager loading, the number of queries will be reduced from 101 to 2.
+      #
+      #   class Post < ActiveRecord::Base
+      #     belongs_to :author
+      #     has_many   :comments
+      #   end
+      #
+      # Consider the following loop using the class above:
+      #
+      #   Post.all.each do |post|
+      #     puts "Post:            " + post.title
+      #     puts "Written by:      " + post.author.name
+      #     puts "Last comment on: " + post.comments.first.created_on
+      #   end
+      #
+      # To iterate over these one hundred posts, we'll generate 201 database queries. Let's
+      # first just optimize it for retrieving the author:
+      #
+      #   Post.includes(:author).each do |post|
+      #
+      # This references the name of the #belongs_to association that also used the <tt>:author</tt>
+      # symbol. After loading the posts, +find+ will collect the +author_id+ from each one and load
+      # all of the referenced authors with one query. Doing so will cut down the number of queries
+      # from 201 to 102.
+      #
+      # We can improve upon the situation further by referencing both associations in the finder with:
+      #
+      #   Post.includes(:author, :comments).each do |post|
+      #
+      # This will load all comments with a single query. This reduces the total number of queries
+      # to 3. In general, the number of queries will be 1 plus the number of associations
+      # named (except if some of the associations are polymorphic #belongs_to - see below).
+      #
+      # To include a deep hierarchy of associations, use a hash:
+      #
+      #   Post.includes(:author, { comments: { author: :gravatar } }).each do |post|
+      #
+      # The above code will load all the comments and all of their associated
+      # authors and gravatars. You can mix and match any combination of symbols,
+      # arrays, and hashes to retrieve the associations you want to load.
+      #
+      # All of this power shouldn't fool you into thinking that you can pull out huge amounts
+      # of data with no performance penalty just because you've reduced the number of queries.
+      # The database still needs to send all the data to Active Record and it still needs to
+      # be processed. So it's no catch-all for performance problems, but it's a great way to
+      # cut down on the number of queries in a situation as the one described above.
+      #
+      # Since only one table is loaded at a time, conditions or orders cannot reference tables
+      # other than the main one. If this is the case, Active Record falls back to the previously
+      # used <tt>LEFT OUTER JOIN</tt> based strategy. For example:
+      #
+      #   Post.includes([:author, :comments]).where(['comments.approved = ?', true])
+      #
+      # This will result in a single SQL query with joins along the lines of:
+      # <tt>LEFT OUTER JOIN comments ON comments.post_id = posts.id</tt> and
+      # <tt>LEFT OUTER JOIN authors ON authors.id = posts.author_id</tt>. Note that using conditions
+      # like this can have unintended consequences.
+      # In the above example, posts with no approved comments are not returned at all because
+      # the conditions apply to the SQL statement as a whole and not just to the association.
+      #
+      # You must disambiguate column references for this fallback to happen, for example
+      # <tt>order: "author.name DESC"</tt> will work but <tt>order: "name DESC"</tt> will not.
+      #
+      # If you want to load all posts (including posts with no approved comments), then write
+      # your own <tt>LEFT OUTER JOIN</tt> query using <tt>ON</tt>:
+      #
+      #   Post.joins("LEFT OUTER JOIN comments ON comments.post_id = posts.id AND comments.approved = '1'")
+      #
+      # In this case, it is usually more natural to include an association which has conditions defined on it:
+      #
+      #   class Post < ActiveRecord::Base
+      #     has_many :approved_comments, -> { where(approved: true) }, class_name: 'Comment'
+      #   end
+      #
+      #   Post.includes(:approved_comments)
+      #
+      # This will load posts and eager load the +approved_comments+ association, which contains
+      # only those comments that have been approved.
+      #
+      # If you eager load an association with a specified <tt>:limit</tt> option, it will be ignored,
+      # returning all the associated objects:
+      #
+      #   class Picture < ActiveRecord::Base
+      #     has_many :most_recent_comments, -> { order('id DESC').limit(10) }, class_name: 'Comment'
+      #   end
+      #
+      #   Picture.includes(:most_recent_comments).first.most_recent_comments # => returns all associated comments.
+      #
+      # Eager loading is supported with polymorphic associations.
+      #
+      #   class Address < ActiveRecord::Base
+      #     belongs_to :addressable, polymorphic: true
+      #   end
+      #
+      # A call that tries to eager load the addressable model
+      #
+      #   Address.includes(:addressable)
+      #
+      # This will execute one query to load the addresses and load the addressables with one
+      # query per addressable type.
+      # For example, if all the addressables are either of class Person or Company, then a total
+      # of 3 queries will be executed. The list of addressable types to load is determined on
+      # the back of the addresses loaded. This is not supported if Active Record has to fallback
+      # to the previous implementation of eager loading and will raise ActiveRecord::EagerLoadPolymorphicError.
+      # The reason is that the parent model's type is a column value so its corresponding table
+      # name cannot be put in the +FROM+/+JOIN+ clauses of that query.
+      #
+      # == Table Aliasing
+      #
+      # Active Record uses table aliasing in the case that a table is referenced multiple times
+      # in a join. If a table is referenced only once, the standard table name is used. The
+      # second time, the table is aliased as <tt>#{reflection_name}_#{parent_table_name}</tt>.
+      # Indexes are appended for any more successive uses of the table name.
+      #
+      #   Post.joins(:comments)
+      #   # => SELECT ... FROM posts INNER JOIN comments ON ...
+      #   Post.joins(:special_comments) # STI
+      #   # => SELECT ... FROM posts INNER JOIN comments ON ... AND comments.type = 'SpecialComment'
+      #   Post.joins(:comments, :special_comments) # special_comments is the reflection name, posts is the parent table name
+      #   # => SELECT ... FROM posts INNER JOIN comments ON ... INNER JOIN comments special_comments_posts
+      #
+      # Acts as tree example:
+      #
+      #   TreeMixin.joins(:children)
+      #   # => SELECT ... FROM mixins INNER JOIN mixins childrens_mixins ...
+      #   TreeMixin.joins(children: :parent)
+      #   # => SELECT ... FROM mixins INNER JOIN mixins childrens_mixins ...
+      #                               INNER JOIN parents_mixins ...
+      #   TreeMixin.joins(children: {parent: :children})
+      #   # => SELECT ... FROM mixins INNER JOIN mixins childrens_mixins ...
+      #                               INNER JOIN parents_mixins ...
+      #                               INNER JOIN mixins childrens_mixins_2
+      #
+      # Has and Belongs to Many join tables use the same idea, but add a <tt>_join</tt> suffix:
+      #
+      #   Post.joins(:categories)
+      #   # => SELECT ... FROM posts INNER JOIN categories_posts ... INNER JOIN categories ...
+      #   Post.joins(categories: :posts)
+      #   # => SELECT ... FROM posts INNER JOIN categories_posts ... INNER JOIN categories ...
+      #                              INNER JOIN categories_posts posts_categories_join INNER JOIN posts posts_categories
+      #   Post.joins(categories: {posts: :categories})
+      #   # => SELECT ... FROM posts INNER JOIN categories_posts ... INNER JOIN categories ...
+      #                              INNER JOIN categories_posts posts_categories_join INNER JOIN posts posts_categories
+      #                              INNER JOIN categories_posts categories_posts_join INNER JOIN categories categories_posts_2
+      #
+      # If you wish to specify your own custom joins using ActiveRecord::QueryMethods#joins method, those table
+      # names will take precedence over the eager associations:
+      #
+      #   Post.joins(:comments).joins("inner join comments ...")
+      #   # => SELECT ... FROM posts INNER JOIN comments_posts ON ... INNER JOIN comments ...
+      #   Post.joins(:comments, :special_comments).joins("inner join comments ...")
+      #   # => SELECT ... FROM posts INNER JOIN comments comments_posts ON ...
+      #                              INNER JOIN comments special_comments_posts ...
+      #                              INNER JOIN comments ...
+      #
+      # Table aliases are automatically truncated according to the maximum length of table identifiers
+      # according to the specific database.
+      #
+      # == Modules
+      #
+      # By default, associations will look for objects within the current module scope. Consider:
+      #
+      #   module MyApplication
+      #     module Business
+      #       class Firm < ActiveRecord::Base
+      #         has_many :clients
+      #       end
+      #
+      #       class Client < ActiveRecord::Base; end
+      #     end
+      #   end
+      #
+      # When <tt>Firm#clients</tt> is called, it will in turn call
+      # <tt>MyApplication::Business::Client.find_all_by_firm_id(firm.id)</tt>.
+      # If you want to associate with a class in another module scope, this can be done by
+      # specifying the complete class name.
+      #
+      #   module MyApplication
+      #     module Business
+      #       class Firm < ActiveRecord::Base; end
+      #     end
+      #
+      #     module Billing
+      #       class Account < ActiveRecord::Base
+      #         belongs_to :firm, class_name: "MyApplication::Business::Firm"
+      #       end
+      #     end
+      #   end
+      #
+      # == Bi-directional associations
+      #
+      # When you specify an association, there is usually an association on the associated model
+      # that specifies the same relationship in reverse. For example, with the following models:
+      #
+      #    class Dungeon < ActiveRecord::Base
+      #      has_many :traps
+      #      has_one :evil_wizard
+      #    end
+      #
+      #    class Trap < ActiveRecord::Base
+      #      belongs_to :dungeon
+      #    end
+      #
+      #    class EvilWizard < ActiveRecord::Base
+      #      belongs_to :dungeon
+      #    end
+      #
+      # The +traps+ association on +Dungeon+ and the +dungeon+ association on +Trap+ are
+      # the inverse of each other, and the inverse of the +dungeon+ association on +EvilWizard+
+      # is the +evil_wizard+ association on +Dungeon+ (and vice-versa). By default,
+      # Active Record can guess the inverse of the association based on the name
+      # of the class. The result is the following:
+      #
+      #    d = Dungeon.first
+      #    t = d.traps.first
+      #    d.object_id == t.dungeon.object_id # => true
+      #
+      # The +Dungeon+ instances +d+ and <tt>t.dungeon</tt> in the above example refer to
+      # the same in-memory instance since the association matches the name of the class.
+      # The result would be the same if we added +:inverse_of+ to our model definitions:
+      #
+      #    class Dungeon < ActiveRecord::Base
+      #      has_many :traps, inverse_of: :dungeon
+      #      has_one :evil_wizard, inverse_of: :dungeon
+      #    end
+      #
+      #    class Trap < ActiveRecord::Base
+      #      belongs_to :dungeon, inverse_of: :traps
+      #    end
+      #
+      #    class EvilWizard < ActiveRecord::Base
+      #      belongs_to :dungeon, inverse_of: :evil_wizard
+      #    end
+      #
+      # There are limitations to <tt>:inverse_of</tt> support:
+      #
+      # * does not work with <tt>:through</tt> associations.
+      # * does not work with <tt>:polymorphic</tt> associations.
+      # * inverse associations for #belongs_to associations #has_many are ignored.
+      #
+      # For more information, see the documentation for the +:inverse_of+ option.
+      #
+      # == Deleting from associations
+      #
+      # === Dependent associations
+      #
+      # #has_many, #has_one, and #belongs_to associations support the <tt>:dependent</tt> option.
+      # This allows you to specify that associated records should be deleted when the owner is
+      # deleted.
+      #
+      # For example:
+      #
+      #     class Author
+      #       has_many :posts, dependent: :destroy
+      #     end
+      #     Author.find(1).destroy # => Will destroy all of the author's posts, too
+      #
+      # The <tt>:dependent</tt> option can have different values which specify how the deletion
+      # is done. For more information, see the documentation for this option on the different
+      # specific association types. When no option is given, the behavior is to do nothing
+      # with the associated records when destroying a record.
+      #
+      # Note that <tt>:dependent</tt> is implemented using Rails' callback
+      # system, which works by processing callbacks in order. Therefore, other
+      # callbacks declared either before or after the <tt>:dependent</tt> option
+      # can affect what it does.
+      #
+      # Note that <tt>:dependent</tt> option is ignored for #has_one <tt>:through</tt> associations.
+      #
+      # === Delete or destroy?
+      #
+      # #has_many and #has_and_belongs_to_many associations have the methods <tt>destroy</tt>,
+      # <tt>delete</tt>, <tt>destroy_all</tt> and <tt>delete_all</tt>.
+      #
+      # For #has_and_belongs_to_many, <tt>delete</tt> and <tt>destroy</tt> are the same: they
+      # cause the records in the join table to be removed.
+      #
+      # For #has_many, <tt>destroy</tt> and <tt>destroy_all</tt> will always call the <tt>destroy</tt> method of the
+      # record(s) being removed so that callbacks are run. However <tt>delete</tt> and <tt>delete_all</tt> will either
+      # do the deletion according to the strategy specified by the <tt>:dependent</tt> option, or
+      # if no <tt>:dependent</tt> option is given, then it will follow the default strategy.
+      # The default strategy is to do nothing (leave the foreign keys with the parent ids set), except for
+      # #has_many <tt>:through</tt>, where the default strategy is <tt>delete_all</tt> (delete
+      # the join records, without running their callbacks).
+      #
+      # There is also a <tt>clear</tt> method which is the same as <tt>delete_all</tt>, except that
+      # it returns the association rather than the records which have been deleted.
+      #
+      # === What gets deleted?
+      #
+      # There is a potential pitfall here: #has_and_belongs_to_many and #has_many <tt>:through</tt>
+      # associations have records in join tables, as well as the associated records. So when we
+      # call one of these deletion methods, what exactly should be deleted?
+      #
+      # The answer is that it is assumed that deletion on an association is about removing the
+      # <i>link</i> between the owner and the associated object(s), rather than necessarily the
+      # associated objects themselves. So with #has_and_belongs_to_many and #has_many
+      # <tt>:through</tt>, the join records will be deleted, but the associated records won't.
+      #
+      # This makes sense if you think about it: if you were to call <tt>post.tags.delete(Tag.find_by(name: 'food'))</tt>
+      # you would want the 'food' tag to be unlinked from the post, rather than for the tag itself
+      # to be removed from the database.
+      #
+      # However, there are examples where this strategy doesn't make sense. For example, suppose
+      # a person has many projects, and each project has many tasks. If we deleted one of a person's
+      # tasks, we would probably not want the project to be deleted. In this scenario, the delete method
+      # won't actually work: it can only be used if the association on the join model is a
+      # #belongs_to. In other situations you are expected to perform operations directly on
+      # either the associated records or the <tt>:through</tt> association.
+      #
+      # With a regular #has_many there is no distinction between the "associated records"
+      # and the "link", so there is only one choice for what gets deleted.
+      #
+      # With #has_and_belongs_to_many and #has_many <tt>:through</tt>, if you want to delete the
+      # associated records themselves, you can always do something along the lines of
+      # <tt>person.tasks.each(&:destroy)</tt>.
+      #
+      # == Type safety with ActiveRecord::AssociationTypeMismatch
+      #
+      # If you attempt to assign an object to an association that doesn't match the inferred
+      # or specified <tt>:class_name</tt>, you'll get an ActiveRecord::AssociationTypeMismatch.
+      #
+      # == Options
+      #
+      # All of the association macros can be specialized through options. This makes cases
+      # more complex than the simple and guessable ones possible.
+      module ClassMethods
+        # Specifies a one-to-many association. The following methods for retrieval and query of
+        # collections of associated objects will be added:
+        #
+        # +collection+ is a placeholder for the symbol passed as the +name+ argument, so
+        # <tt>has_many :clients</tt> would add among others <tt>clients.empty?</tt>.
+        #
+        # [collection]
+        #   Returns a Relation of all the associated objects.
+        #   An empty Relation is returned if none are found.
+        # [collection<<(object, ...)]
+        #   Adds one or more objects to the collection by setting their foreign keys to the collection's primary key.
+        #   Note that this operation instantly fires update SQL without waiting for the save or update call on the
+        #   parent object, unless the parent object is a new record.
+        #   This will also run validations and callbacks of associated object(s).
+        # [collection.delete(object, ...)]
+        #   Removes one or more objects from the collection by setting their foreign keys to +NULL+.
+        #   Objects will be in addition destroyed if they're associated with <tt>dependent: :destroy</tt>,
+        #   and deleted if they're associated with <tt>dependent: :delete_all</tt>.
+        #
+        #   If the <tt>:through</tt> option is used, then the join records are deleted (rather than
+        #   nullified) by default, but you can specify <tt>dependent: :destroy</tt> or
+        #   <tt>dependent: :nullify</tt> to override this.
+        # [collection.destroy(object, ...)]
+        #   Removes one or more objects from the collection by running <tt>destroy</tt> on
+        #   each record, regardless of any dependent option, ensuring callbacks are run.
+        #
+        #   If the <tt>:through</tt> option is used, then the join records are destroyed
+        #   instead, not the objects themselves.
+        # [collection=objects]
+        #   Replaces the collections content by deleting and adding objects as appropriate. If the <tt>:through</tt>
+        #   option is true callbacks in the join models are triggered except destroy callbacks, since deletion is
+        #   direct by default. You can specify <tt>dependent: :destroy</tt> or
+        #   <tt>dependent: :nullify</tt> to override this.
+        # [collection_singular_ids]
+        #   Returns an array of the associated objects' ids
+        # [collection_singular_ids=ids]
+        #   Replace the collection with the objects identified by the primary keys in +ids+. This
+        #   method loads the models and calls <tt>collection=</tt>. See above.
+        # [collection.clear]
+        #   Removes every object from the collection. This destroys the associated objects if they
+        #   are associated with <tt>dependent: :destroy</tt>, deletes them directly from the
+        #   database if <tt>dependent: :delete_all</tt>, otherwise sets their foreign keys to +NULL+.
+        #   If the <tt>:through</tt> option is true no destroy callbacks are invoked on the join models.
+        #   Join models are directly deleted.
+        # [collection.empty?]
+        #   Returns +true+ if there are no associated objects.
+        # [collection.size]
+        #   Returns the number of associated objects.
+        # [collection.find(...)]
+        #   Finds an associated object according to the same rules as ActiveRecord::FinderMethods#find.
+        # [collection.exists?(...)]
+        #   Checks whether an associated object with the given conditions exists.
+        #   Uses the same rules as ActiveRecord::FinderMethods#exists?.
+        # [collection.build(attributes = {}, ...)]
+        #   Returns one or more new objects of the collection type that have been instantiated
+        #   with +attributes+ and linked to this object through a foreign key, but have not yet
+        #   been saved.
+        # [collection.create(attributes = {})]
+        #   Returns a new object of the collection type that has been instantiated
+        #   with +attributes+, linked to this object through a foreign key, and that has already
+        #   been saved (if it passed the validation). *Note*: This only works if the base model
+        #   already exists in the DB, not if it is a new (unsaved) record!
+        # [collection.create!(attributes = {})]
+        #   Does the same as <tt>collection.create</tt>, but raises ActiveRecord::RecordInvalid
+        #   if the record is invalid.
+        # [collection.reload]
+        #   Returns a Relation of all of the associated objects, forcing a database read.
+        #   An empty Relation is returned if none are found.
+        #
+        # === Example
+        #
+        # A <tt>Firm</tt> class declares <tt>has_many :clients</tt>, which will add:
+        # * <tt>Firm#clients</tt> (similar to <tt>Client.where(firm_id: id)</tt>)
+        # * <tt>Firm#clients<<</tt>
+        # * <tt>Firm#clients.delete</tt>
+        # * <tt>Firm#clients.destroy</tt>
+        # * <tt>Firm#clients=</tt>
+        # * <tt>Firm#client_ids</tt>
+        # * <tt>Firm#client_ids=</tt>
+        # * <tt>Firm#clients.clear</tt>
+        # * <tt>Firm#clients.empty?</tt> (similar to <tt>firm.clients.size == 0</tt>)
+        # * <tt>Firm#clients.size</tt> (similar to <tt>Client.count "firm_id = #{id}"</tt>)
+        # * <tt>Firm#clients.find</tt> (similar to <tt>Client.where(firm_id: id).find(id)</tt>)
+        # * <tt>Firm#clients.exists?(name: 'ACME')</tt> (similar to <tt>Client.exists?(name: 'ACME', firm_id: firm.id)</tt>)
+        # * <tt>Firm#clients.build</tt> (similar to <tt>Client.new("firm_id" => id)</tt>)
+        # * <tt>Firm#clients.create</tt> (similar to <tt>c = Client.new("firm_id" => id); c.save; c</tt>)
+        # * <tt>Firm#clients.create!</tt> (similar to <tt>c = Client.new("firm_id" => id); c.save!</tt>)
+        # * <tt>Firm#clients.reload</tt>
+        # The declaration can also include an +options+ hash to specialize the behavior of the association.
+        #
+        # === Scopes
+        #
+        # You can pass a second argument +scope+ as a callable (i.e. proc or
+        # lambda) to retrieve a specific set of records or customize the generated
+        # query when you access the associated collection.
+        #
+        # Scope examples:
+        #   has_many :comments, -> { where(author_id: 1) }
+        #   has_many :employees, -> { joins(:address) }
+        #   has_many :posts, ->(blog) { where("max_post_length > ?", blog.max_post_length) }
+        #
+        # === Extensions
+        #
+        # The +extension+ argument allows you to pass a block into a has_many
+        # association. This is useful for adding new finders, creators and other
+        # factory-type methods to be used as part of the association.
+        #
+        # Extension examples:
+        #   has_many :employees do
+        #     def find_or_create_by_name(name)
+        #       first_name, last_name = name.split(" ", 2)
+        #       find_or_create_by(first_name: first_name, last_name: last_name)
+        #     end
+        #   end
+        #
+        # === Options
+        # [:class_name]
+        #   Specify the class name of the association. Use it only if that name can't be inferred
+        #   from the association name. So <tt>has_many :products</tt> will by default be linked
+        #   to the +Product+ class, but if the real class name is +SpecialProduct+, you'll have to
+        #   specify it with this option.
+        # [:foreign_key]
+        #   Specify the foreign key used for the association. By default this is guessed to be the name
+        #   of this class in lower-case and "_id" suffixed. So a Person class that makes a #has_many
+        #   association will use "person_id" as the default <tt>:foreign_key</tt>.
+        # [:foreign_type]
+        #   Specify the column used to store the associated object's type, if this is a polymorphic
+        #   association. By default this is guessed to be the name of the polymorphic association
+        #   specified on "as" option with a "_type" suffix. So a class that defines a
+        #   <tt>has_many :tags, as: :taggable</tt> association will use "taggable_type" as the
+        #   default <tt>:foreign_type</tt>.
+        # [:primary_key]
+        #   Specify the name of the column to use as the primary key for the association. By default this is +id+.
+        # [:dependent]
+        #   Controls what happens to the associated objects when
+        #   their owner is destroyed. Note that these are implemented as
+        #   callbacks, and Rails executes callbacks in order. Therefore, other
+        #   similar callbacks may affect the <tt>:dependent</tt> behavior, and the
+        #   <tt>:dependent</tt> behavior may affect other callbacks.
+        #
+        #   * <tt>:destroy</tt> causes all the associated objects to also be destroyed.
+        #   * <tt>:delete_all</tt> causes all the associated objects to be deleted directly from the database (so callbacks will not be executed).
+        #   * <tt>:nullify</tt> causes the foreign keys to be set to +NULL+. Callbacks are not executed.
+        #   * <tt>:restrict_with_exception</tt> causes an exception to be raised if there are any associated records.
+        #   * <tt>:restrict_with_error</tt> causes an error to be added to the owner if there are any associated objects.
+        #
+        #   If using with the <tt>:through</tt> option, the association on the join model must be
+        #   a #belongs_to, and the records which get deleted are the join records, rather than
+        #   the associated records.
+        #
+        #   If using <tt>dependent: :destroy</tt> on a scoped association, only the scoped objects are destroyed.
+        #   For example, if a Post model defines
+        #   <tt>has_many :comments, -> { where published: true }, dependent: :destroy</tt> and <tt>destroy</tt> is
+        #   called on a post, only published comments are destroyed. This means that any unpublished comments in the
+        #   database would still contain a foreign key pointing to the now deleted post.
+        # [:counter_cache]
+        #   This option can be used to configure a custom named <tt>:counter_cache.</tt> You only need this option,
+        #   when you customized the name of your <tt>:counter_cache</tt> on the #belongs_to association.
+        # [:as]
+        #   Specifies a polymorphic interface (See #belongs_to).
+        # [:through]
+        #   Specifies an association through which to perform the query. This can be any other type
+        #   of association, including other <tt>:through</tt> associations. Options for <tt>:class_name</tt>,
+        #   <tt>:primary_key</tt> and <tt>:foreign_key</tt> are ignored, as the association uses the
+        #   source reflection.
+        #
+        #   If the association on the join model is a #belongs_to, the collection can be modified
+        #   and the records on the <tt>:through</tt> model will be automatically created and removed
+        #   as appropriate. Otherwise, the collection is read-only, so you should manipulate the
+        #   <tt>:through</tt> association directly.
+        #
+        #   If you are going to modify the association (rather than just read from it), then it is
+        #   a good idea to set the <tt>:inverse_of</tt> option on the source association on the
+        #   join model. This allows associated records to be built which will automatically create
+        #   the appropriate join model records when they are saved. (See the 'Association Join Models'
+        #   section above.)
+        # [:source]
+        #   Specifies the source association name used by #has_many <tt>:through</tt> queries.
+        #   Only use it if the name cannot be inferred from the association.
+        #   <tt>has_many :subscribers, through: :subscriptions</tt> will look for either <tt>:subscribers</tt> or
+        #   <tt>:subscriber</tt> on Subscription, unless a <tt>:source</tt> is given.
+        # [:source_type]
+        #   Specifies type of the source association used by #has_many <tt>:through</tt> queries where the source
+        #   association is a polymorphic #belongs_to.
+        # [:validate]
+        #   When set to +true+, validates new objects added to association when saving the parent object. +true+ by default.
+        #   If you want to ensure associated objects are revalidated on every update, use +validates_associated+.
+        # [:autosave]
+        #   If true, always save the associated objects or destroy them if marked for destruction,
+        #   when saving the parent object. If false, never save or destroy the associated objects.
+        #   By default, only save associated objects that are new records. This option is implemented as a
+        #   +before_save+ callback. Because callbacks are run in the order they are defined, associated objects
+        #   may need to be explicitly saved in any user-defined +before_save+ callbacks.
+        #
+        #   Note that NestedAttributes::ClassMethods#accepts_nested_attributes_for sets
+        #   <tt>:autosave</tt> to <tt>true</tt>.
+        # [:inverse_of]
+        #   Specifies the name of the #belongs_to association on the associated object
+        #   that is the inverse of this #has_many association. Does not work in combination
+        #   with <tt>:through</tt> or <tt>:as</tt> options.
+        #   See ActiveRecord::Associations::ClassMethods's overview on Bi-directional associations for more detail.
+        # [:extend]
+        #   Specifies a module or array of modules that will be extended into the association object returned.
+        #   Useful for defining methods on associations, especially when they should be shared between multiple
+        #   association objects.
+        #
+        # Option examples:
+        #   has_many :comments, -> { order("posted_on") }
+        #   has_many :comments, -> { includes(:author) }
+        #   has_many :people, -> { where(deleted: false).order("name") }, class_name: "Person"
+        #   has_many :tracks, -> { order("position") }, dependent: :destroy
+        #   has_many :comments, dependent: :nullify
+        #   has_many :tags, as: :taggable
+        #   has_many :reports, -> { readonly }
+        #   has_many :subscribers, through: :subscriptions, source: :user
+        def has_many(name, scope = nil, **options, &extension)
+          reflection = Builder::HasMany.build(self, name, scope, options, &extension)
+          Reflection.add_reflection self, name, reflection
+        end
+
+        # Specifies a one-to-one association with another class. This method should only be used
+        # if the other class contains the foreign key. If the current class contains the foreign key,
+        # then you should use #belongs_to instead. See also ActiveRecord::Associations::ClassMethods's overview
+        # on when to use #has_one and when to use #belongs_to.
+        #
+        # The following methods for retrieval and query of a single associated object will be added:
+        #
+        # +association+ is a placeholder for the symbol passed as the +name+ argument, so
+        # <tt>has_one :manager</tt> would add among others <tt>manager.nil?</tt>.
+        #
+        # [association]
+        #   Returns the associated object. +nil+ is returned if none is found.
+        # [association=(associate)]
+        #   Assigns the associate object, extracts the primary key, sets it as the foreign key,
+        #   and saves the associate object. To avoid database inconsistencies, permanently deletes an existing
+        #   associated object when assigning a new one, even if the new one isn't saved to database.
+        # [build_association(attributes = {})]
+        #   Returns a new object of the associated type that has been instantiated
+        #   with +attributes+ and linked to this object through a foreign key, but has not
+        #   yet been saved.
+        # [create_association(attributes = {})]
+        #   Returns a new object of the associated type that has been instantiated
+        #   with +attributes+, linked to this object through a foreign key, and that
+        #   has already been saved (if it passed the validation).
+        # [create_association!(attributes = {})]
+        #   Does the same as <tt>create_association</tt>, but raises ActiveRecord::RecordInvalid
+        #   if the record is invalid.
+        # [reload_association]
+        #   Returns the associated object, forcing a database read.
+        #
+        # === Example
+        #
+        # An Account class declares <tt>has_one :beneficiary</tt>, which will add:
+        # * <tt>Account#beneficiary</tt> (similar to <tt>Beneficiary.where(account_id: id).first</tt>)
+        # * <tt>Account#beneficiary=(beneficiary)</tt> (similar to <tt>beneficiary.account_id = account.id; beneficiary.save</tt>)
+        # * <tt>Account#build_beneficiary</tt> (similar to <tt>Beneficiary.new("account_id" => id)</tt>)
+        # * <tt>Account#create_beneficiary</tt> (similar to <tt>b = Beneficiary.new("account_id" => id); b.save; b</tt>)
+        # * <tt>Account#create_beneficiary!</tt> (similar to <tt>b = Beneficiary.new("account_id" => id); b.save!; b</tt>)
+        # * <tt>Account#reload_beneficiary</tt>
+        #
+        # === Scopes
+        #
+        # You can pass a second argument +scope+ as a callable (i.e. proc or
+        # lambda) to retrieve a specific record or customize the generated query
+        # when you access the associated object.
+        #
+        # Scope examples:
+        #   has_one :author, -> { where(comment_id: 1) }
+        #   has_one :employer, -> { joins(:company) }
+        #   has_one :latest_post, ->(blog) { where("created_at > ?", blog.enabled_at) }
+        #
+        # === Options
+        #
+        # The declaration can also include an +options+ hash to specialize the behavior of the association.
+        #
+        # Options are:
+        # [:class_name]
+        #   Specify the class name of the association. Use it only if that name can't be inferred
+        #   from the association name. So <tt>has_one :manager</tt> will by default be linked to the Manager class, but
+        #   if the real class name is Person, you'll have to specify it with this option.
+        # [:dependent]
+        #   Controls what happens to the associated object when
+        #   its owner is destroyed:
+        #
+        #   * <tt>:destroy</tt> causes the associated object to also be destroyed
+        #   * <tt>:delete</tt> causes the associated object to be deleted directly from the database (so callbacks will not execute)
+        #   * <tt>:nullify</tt> causes the foreign key to be set to +NULL+. Callbacks are not executed.
+        #   * <tt>:restrict_with_exception</tt> causes an exception to be raised if there is an associated record
+        #   * <tt>:restrict_with_error</tt> causes an error to be added to the owner if there is an associated object
+        #
+        #   Note that <tt>:dependent</tt> option is ignored when using <tt>:through</tt> option.
+        # [:foreign_key]
+        #   Specify the foreign key used for the association. By default this is guessed to be the name
+        #   of this class in lower-case and "_id" suffixed. So a Person class that makes a #has_one association
+        #   will use "person_id" as the default <tt>:foreign_key</tt>.
+        # [:foreign_type]
+        #   Specify the column used to store the associated object's type, if this is a polymorphic
+        #   association. By default this is guessed to be the name of the polymorphic association
+        #   specified on "as" option with a "_type" suffix. So a class that defines a
+        #   <tt>has_one :tag, as: :taggable</tt> association will use "taggable_type" as the
+        #   default <tt>:foreign_type</tt>.
+        # [:primary_key]
+        #   Specify the method that returns the primary key used for the association. By default this is +id+.
+        # [:as]
+        #   Specifies a polymorphic interface (See #belongs_to).
+        # [:through]
+        #   Specifies a Join Model through which to perform the query. Options for <tt>:class_name</tt>,
+        #   <tt>:primary_key</tt>, and <tt>:foreign_key</tt> are ignored, as the association uses the
+        #   source reflection. You can only use a <tt>:through</tt> query through a #has_one
+        #   or #belongs_to association on the join model.
+        # [:source]
+        #   Specifies the source association name used by #has_one <tt>:through</tt> queries.
+        #   Only use it if the name cannot be inferred from the association.
+        #   <tt>has_one :favorite, through: :favorites</tt> will look for a
+        #   <tt>:favorite</tt> on Favorite, unless a <tt>:source</tt> is given.
+        # [:source_type]
+        #   Specifies type of the source association used by #has_one <tt>:through</tt> queries where the source
+        #   association is a polymorphic #belongs_to.
+        # [:validate]
+        #   When set to +true+, validates new objects added to association when saving the parent object. +false+ by default.
+        #   If you want to ensure associated objects are revalidated on every update, use +validates_associated+.
+        # [:autosave]
+        #   If true, always save the associated object or destroy it if marked for destruction,
+        #   when saving the parent object. If false, never save or destroy the associated object.
+        #   By default, only save the associated object if it's a new record.
+        #
+        #   Note that NestedAttributes::ClassMethods#accepts_nested_attributes_for sets
+        #   <tt>:autosave</tt> to <tt>true</tt>.
+        # [:inverse_of]
+        #   Specifies the name of the #belongs_to association on the associated object
+        #   that is the inverse of this #has_one association. Does not work in combination
+        #   with <tt>:through</tt> or <tt>:as</tt> options.
+        #   See ActiveRecord::Associations::ClassMethods's overview on Bi-directional associations for more detail.
+        # [:required]
+        #   When set to +true+, the association will also have its presence validated.
+        #   This will validate the association itself, not the id. You can use
+        #   +:inverse_of+ to avoid an extra query during validation.
+        #
+        # Option examples:
+        #   has_one :credit_card, dependent: :destroy  # destroys the associated credit card
+        #   has_one :credit_card, dependent: :nullify  # updates the associated records foreign
+        #                                                 # key value to NULL rather than destroying it
+        #   has_one :last_comment, -> { order('posted_on') }, class_name: "Comment"
+        #   has_one :project_manager, -> { where(role: 'project_manager') }, class_name: "Person"
+        #   has_one :attachment, as: :attachable
+        #   has_one :boss, -> { readonly }
+        #   has_one :club, through: :membership
+        #   has_one :primary_address, -> { where(primary: true) }, through: :addressables, source: :addressable
+        #   has_one :credit_card, required: true
+        def has_one(name, scope = nil, **options)
+          reflection = Builder::HasOne.build(self, name, scope, options)
+          Reflection.add_reflection self, name, reflection
         end
 
-        habtm_reflection = ActiveRecord::Reflection::HasAndBelongsToManyReflection.new(name, scope, options, self)
+        # Specifies a one-to-one association with another class. This method should only be used
+        # if this class contains the foreign key. If the other class contains the foreign key,
+        # then you should use #has_one instead. See also ActiveRecord::Associations::ClassMethods's overview
+        # on when to use #has_one and when to use #belongs_to.
+        #
+        # Methods will be added for retrieval and query for a single associated object, for which
+        # this object holds an id:
+        #
+        # +association+ is a placeholder for the symbol passed as the +name+ argument, so
+        # <tt>belongs_to :author</tt> would add among others <tt>author.nil?</tt>.
+        #
+        # [association]
+        #   Returns the associated object. +nil+ is returned if none is found.
+        # [association=(associate)]
+        #   Assigns the associate object, extracts the primary key, and sets it as the foreign key.
+        # [build_association(attributes = {})]
+        #   Returns a new object of the associated type that has been instantiated
+        #   with +attributes+ and linked to this object through a foreign key, but has not yet been saved.
+        # [create_association(attributes = {})]
+        #   Returns a new object of the associated type that has been instantiated
+        #   with +attributes+, linked to this object through a foreign key, and that
+        #   has already been saved (if it passed the validation).
+        # [create_association!(attributes = {})]
+        #   Does the same as <tt>create_association</tt>, but raises ActiveRecord::RecordInvalid
+        #   if the record is invalid.
+        # [reload_association]
+        #   Returns the associated object, forcing a database read.
+        #
+        # === Example
+        #
+        # A Post class declares <tt>belongs_to :author</tt>, which will add:
+        # * <tt>Post#author</tt> (similar to <tt>Author.find(author_id)</tt>)
+        # * <tt>Post#author=(author)</tt> (similar to <tt>post.author_id = author.id</tt>)
+        # * <tt>Post#build_author</tt> (similar to <tt>post.author = Author.new</tt>)
+        # * <tt>Post#create_author</tt> (similar to <tt>post.author = Author.new; post.author.save; post.author</tt>)
+        # * <tt>Post#create_author!</tt> (similar to <tt>post.author = Author.new; post.author.save!; post.author</tt>)
+        # * <tt>Post#reload_author</tt>
+        # The declaration can also include an +options+ hash to specialize the behavior of the association.
+        #
+        # === Scopes
+        #
+        # You can pass a second argument +scope+ as a callable (i.e. proc or
+        # lambda) to retrieve a specific record or customize the generated query
+        # when you access the associated object.
+        #
+        # Scope examples:
+        #   belongs_to :firm, -> { where(id: 2) }
+        #   belongs_to :user, -> { joins(:friends) }
+        #   belongs_to :level, ->(game) { where("game_level > ?", game.current_level) }
+        #
+        # === Options
+        #
+        # [:class_name]
+        #   Specify the class name of the association. Use it only if that name can't be inferred
+        #   from the association name. So <tt>belongs_to :author</tt> will by default be linked to the Author class, but
+        #   if the real class name is Person, you'll have to specify it with this option.
+        # [:foreign_key]
+        #   Specify the foreign key used for the association. By default this is guessed to be the name
+        #   of the association with an "_id" suffix. So a class that defines a <tt>belongs_to :person</tt>
+        #   association will use "person_id" as the default <tt>:foreign_key</tt>. Similarly,
+        #   <tt>belongs_to :favorite_person, class_name: "Person"</tt> will use a foreign key
+        #   of "favorite_person_id".
+        # [:foreign_type]
+        #   Specify the column used to store the associated object's type, if this is a polymorphic
+        #   association. By default this is guessed to be the name of the association with a "_type"
+        #   suffix. So a class that defines a <tt>belongs_to :taggable, polymorphic: true</tt>
+        #   association will use "taggable_type" as the default <tt>:foreign_type</tt>.
+        # [:primary_key]
+        #   Specify the method that returns the primary key of associated object used for the association.
+        #   By default this is id.
+        # [:dependent]
+        #   If set to <tt>:destroy</tt>, the associated object is destroyed when this object is. If set to
+        #   <tt>:delete</tt>, the associated object is deleted *without* calling its destroy method.
+        #   This option should not be specified when #belongs_to is used in conjunction with
+        #   a #has_many relationship on another class because of the potential to leave
+        #   orphaned records behind.
+        # [:counter_cache]
+        #   Caches the number of belonging objects on the associate class through the use of CounterCache::ClassMethods#increment_counter
+        #   and CounterCache::ClassMethods#decrement_counter. The counter cache is incremented when an object of this
+        #   class is created and decremented when it's destroyed. This requires that a column
+        #   named <tt>#{table_name}_count</tt> (such as +comments_count+ for a belonging Comment class)
+        #   is used on the associate class (such as a Post class) - that is the migration for
+        #   <tt>#{table_name}_count</tt> is created on the associate class (such that <tt>Post.comments_count</tt> will
+        #   return the count cached, see note below). You can also specify a custom counter
+        #   cache column by providing a column name instead of a +true+/+false+ value to this
+        #   option (e.g., <tt>counter_cache: :my_custom_counter</tt>.)
+        #   Note: Specifying a counter cache will add it to that model's list of readonly attributes
+        #   using +attr_readonly+.
+        # [:polymorphic]
+        #   Specify this association is a polymorphic association by passing +true+.
+        #   Note: If you've enabled the counter cache, then you may want to add the counter cache attribute
+        #   to the +attr_readonly+ list in the associated classes (e.g. <tt>class Post; attr_readonly :comments_count; end</tt>).
+        # [:validate]
+        #   When set to +true+, validates new objects added to association when saving the parent object. +false+ by default.
+        #   If you want to ensure associated objects are revalidated on every update, use +validates_associated+.
+        # [:autosave]
+        #   If true, always save the associated object or destroy it if marked for destruction, when
+        #   saving the parent object.
+        #   If false, never save or destroy the associated object.
+        #   By default, only save the associated object if it's a new record.
+        #
+        #   Note that NestedAttributes::ClassMethods#accepts_nested_attributes_for
+        #   sets <tt>:autosave</tt> to <tt>true</tt>.
+        # [:touch]
+        #   If true, the associated object will be touched (the updated_at/on attributes set to current time)
+        #   when this record is either saved or destroyed. If you specify a symbol, that attribute
+        #   will be updated with the current time in addition to the updated_at/on attribute.
+        #   Please note that with touching no validation is performed and only the +after_touch+,
+        #   +after_commit+ and +after_rollback+ callbacks are executed.
+        # [:inverse_of]
+        #   Specifies the name of the #has_one or #has_many association on the associated
+        #   object that is the inverse of this #belongs_to association. Does not work in
+        #   combination with the <tt>:polymorphic</tt> options.
+        #   See ActiveRecord::Associations::ClassMethods's overview on Bi-directional associations for more detail.
+        # [:optional]
+        #   When set to +true+, the association will not have its presence validated.
+        # [:required]
+        #   When set to +true+, the association will also have its presence validated.
+        #   This will validate the association itself, not the id. You can use
+        #   +:inverse_of+ to avoid an extra query during validation.
+        #   NOTE: <tt>required</tt> is set to <tt>true</tt> by default and is deprecated. If
+        #   you don't want to have association presence validated, use <tt>optional: true</tt>.
+        # [:default]
+        #   Provide a callable (i.e. proc or lambda) to specify that the association should
+        #   be initialized with a particular record before validation.
+        #
+        # Option examples:
+        #   belongs_to :firm, foreign_key: "client_of"
+        #   belongs_to :person, primary_key: "name", foreign_key: "person_name"
+        #   belongs_to :author, class_name: "Person", foreign_key: "author_id"
+        #   belongs_to :valid_coupon, ->(o) { where "discounts > ?", o.payments_count },
+        #                             class_name: "Coupon", foreign_key: "coupon_id"
+        #   belongs_to :attachable, polymorphic: true
+        #   belongs_to :project, -> { readonly }
+        #   belongs_to :post, counter_cache: true
+        #   belongs_to :comment, touch: true
+        #   belongs_to :company, touch: :employees_last_updated_at
+        #   belongs_to :user, optional: true
+        #   belongs_to :account, default: -> { company.account }
+        def belongs_to(name, scope = nil, **options)
+          reflection = Builder::BelongsTo.build(self, name, scope, options)
+          Reflection.add_reflection self, name, reflection
+        end
 
-        builder = Builder::HasAndBelongsToMany.new name, self, options
+        # Specifies a many-to-many relationship with another class. This associates two classes via an
+        # intermediate join table. Unless the join table is explicitly specified as an option, it is
+        # guessed using the lexical order of the class names. So a join between Developer and Project
+        # will give the default join table name of "developers_projects" because "D" precedes "P" alphabetically.
+        # Note that this precedence is calculated using the <tt><</tt> operator for String. This
+        # means that if the strings are of different lengths, and the strings are equal when compared
+        # up to the shortest length, then the longer string is considered of higher
+        # lexical precedence than the shorter one. For example, one would expect the tables "paper_boxes" and "papers"
+        # to generate a join table name of "papers_paper_boxes" because of the length of the name "paper_boxes",
+        # but it in fact generates a join table name of "paper_boxes_papers". Be aware of this caveat, and use the
+        # custom <tt>:join_table</tt> option if you need to.
+        # If your tables share a common prefix, it will only appear once at the beginning. For example,
+        # the tables "catalog_categories" and "catalog_products" generate a join table name of "catalog_categories_products".
+        #
+        # The join table should not have a primary key or a model associated with it. You must manually generate the
+        # join table with a migration such as this:
+        #
+        #   class CreateDevelopersProjectsJoinTable < ActiveRecord::Migration[5.0]
+        #     def change
+        #       create_join_table :developers, :projects
+        #     end
+        #   end
+        #
+        # It's also a good idea to add indexes to each of those columns to speed up the joins process.
+        # However, in MySQL it is advised to add a compound index for both of the columns as MySQL only
+        # uses one index per table during the lookup.
+        #
+        # Adds the following methods for retrieval and query:
+        #
+        # +collection+ is a placeholder for the symbol passed as the +name+ argument, so
+        # <tt>has_and_belongs_to_many :categories</tt> would add among others <tt>categories.empty?</tt>.
+        #
+        # [collection]
+        #   Returns a Relation of all the associated objects.
+        #   An empty Relation is returned if none are found.
+        # [collection<<(object, ...)]
+        #   Adds one or more objects to the collection by creating associations in the join table
+        #   (<tt>collection.push</tt> and <tt>collection.concat</tt> are aliases to this method).
+        #   Note that this operation instantly fires update SQL without waiting for the save or update call on the
+        #   parent object, unless the parent object is a new record.
+        # [collection.delete(object, ...)]
+        #   Removes one or more objects from the collection by removing their associations from the join table.
+        #   This does not destroy the objects.
+        # [collection.destroy(object, ...)]
+        #   Removes one or more objects from the collection by running destroy on each association in the join table, overriding any dependent option.
+        #   This does not destroy the objects.
+        # [collection=objects]
+        #   Replaces the collection's content by deleting and adding objects as appropriate.
+        # [collection_singular_ids]
+        #   Returns an array of the associated objects' ids.
+        # [collection_singular_ids=ids]
+        #   Replace the collection by the objects identified by the primary keys in +ids+.
+        # [collection.clear]
+        #   Removes every object from the collection. This does not destroy the objects.
+        # [collection.empty?]
+        #   Returns +true+ if there are no associated objects.
+        # [collection.size]
+        #   Returns the number of associated objects.
+        # [collection.find(id)]
+        #   Finds an associated object responding to the +id+ and that
+        #   meets the condition that it has to be associated with this object.
+        #   Uses the same rules as ActiveRecord::FinderMethods#find.
+        # [collection.exists?(...)]
+        #   Checks whether an associated object with the given conditions exists.
+        #   Uses the same rules as ActiveRecord::FinderMethods#exists?.
+        # [collection.build(attributes = {})]
+        #   Returns a new object of the collection type that has been instantiated
+        #   with +attributes+ and linked to this object through the join table, but has not yet been saved.
+        # [collection.create(attributes = {})]
+        #   Returns a new object of the collection type that has been instantiated
+        #   with +attributes+, linked to this object through the join table, and that has already been
+        #   saved (if it passed the validation).
+        # [collection.reload]
+        #   Returns a Relation of all of the associated objects, forcing a database read.
+        #   An empty Relation is returned if none are found.
+        #
+        # === Example
+        #
+        # A Developer class declares <tt>has_and_belongs_to_many :projects</tt>, which will add:
+        # * <tt>Developer#projects</tt>
+        # * <tt>Developer#projects<<</tt>
+        # * <tt>Developer#projects.delete</tt>
+        # * <tt>Developer#projects.destroy</tt>
+        # * <tt>Developer#projects=</tt>
+        # * <tt>Developer#project_ids</tt>
+        # * <tt>Developer#project_ids=</tt>
+        # * <tt>Developer#projects.clear</tt>
+        # * <tt>Developer#projects.empty?</tt>
+        # * <tt>Developer#projects.size</tt>
+        # * <tt>Developer#projects.find(id)</tt>
+        # * <tt>Developer#projects.exists?(...)</tt>
+        # * <tt>Developer#projects.build</tt> (similar to <tt>Project.new("developer_id" => id)</tt>)
+        # * <tt>Developer#projects.create</tt> (similar to <tt>c = Project.new("developer_id" => id); c.save; c</tt>)
+        # * <tt>Developer#projects.reload</tt>
+        # The declaration may include an +options+ hash to specialize the behavior of the association.
+        #
+        # === Scopes
+        #
+        # You can pass a second argument +scope+ as a callable (i.e. proc or
+        # lambda) to retrieve a specific set of records or customize the generated
+        # query when you access the associated collection.
+        #
+        # Scope examples:
+        #   has_and_belongs_to_many :projects, -> { includes(:milestones, :manager) }
+        #   has_and_belongs_to_many :categories, ->(post) {
+        #     where("default_category = ?", post.default_category)
+        #
+        # === Extensions
+        #
+        # The +extension+ argument allows you to pass a block into a
+        # has_and_belongs_to_many association. This is useful for adding new
+        # finders, creators and other factory-type methods to be used as part of
+        # the association.
+        #
+        # Extension examples:
+        #   has_and_belongs_to_many :contractors do
+        #     def find_or_create_by_name(name)
+        #       first_name, last_name = name.split(" ", 2)
+        #       find_or_create_by(first_name: first_name, last_name: last_name)
+        #     end
+        #   end
+        #
+        # === Options
+        #
+        # [:class_name]
+        #   Specify the class name of the association. Use it only if that name can't be inferred
+        #   from the association name. So <tt>has_and_belongs_to_many :projects</tt> will by default be linked to the
+        #   Project class, but if the real class name is SuperProject, you'll have to specify it with this option.
+        # [:join_table]
+        #   Specify the name of the join table if the default based on lexical order isn't what you want.
+        #   <b>WARNING:</b> If you're overwriting the table name of either class, the +table_name+ method
+        #   MUST be declared underneath any #has_and_belongs_to_many declaration in order to work.
+        # [:foreign_key]
+        #   Specify the foreign key used for the association. By default this is guessed to be the name
+        #   of this class in lower-case and "_id" suffixed. So a Person class that makes
+        #   a #has_and_belongs_to_many association to Project will use "person_id" as the
+        #   default <tt>:foreign_key</tt>.
+        # [:association_foreign_key]
+        #   Specify the foreign key used for the association on the receiving side of the association.
+        #   By default this is guessed to be the name of the associated class in lower-case and "_id" suffixed.
+        #   So if a Person class makes a #has_and_belongs_to_many association to Project,
+        #   the association will use "project_id" as the default <tt>:association_foreign_key</tt>.
+        # [:validate]
+        #   When set to +true+, validates new objects added to association when saving the parent object. +true+ by default.
+        #   If you want to ensure associated objects are revalidated on every update, use +validates_associated+.
+        # [:autosave]
+        #   If true, always save the associated objects or destroy them if marked for destruction, when
+        #   saving the parent object.
+        #   If false, never save or destroy the associated objects.
+        #   By default, only save associated objects that are new records.
+        #
+        #   Note that NestedAttributes::ClassMethods#accepts_nested_attributes_for sets
+        #   <tt>:autosave</tt> to <tt>true</tt>.
+        #
+        # Option examples:
+        #   has_and_belongs_to_many :projects
+        #   has_and_belongs_to_many :projects, -> { includes(:milestones, :manager) }
+        #   has_and_belongs_to_many :nations, class_name: "Country"
+        #   has_and_belongs_to_many :categories, join_table: "prods_cats"
+        #   has_and_belongs_to_many :categories, -> { readonly }
+        def has_and_belongs_to_many(name, scope = nil, **options, &extension)
+          habtm_reflection = ActiveRecord::Reflection::HasAndBelongsToManyReflection.new(name, scope, options, self)
 
-        join_model = builder.through_model
+          builder = Builder::HasAndBelongsToMany.new name, self, options
 
-        const_set join_model.name, join_model
-        private_constant join_model.name
+          join_model = builder.through_model
 
-        middle_reflection = builder.middle_reflection join_model
+          const_set join_model.name, join_model
+          private_constant join_model.name
 
-        Builder::HasMany.define_callbacks self, middle_reflection
-        Reflection.add_reflection self, middle_reflection.name, middle_reflection
-        middle_reflection.parent_reflection = habtm_reflection
+          middle_reflection = builder.middle_reflection join_model
 
-        include Module.new {
-          class_eval <<-RUBY, __FILE__, __LINE__ + 1
-          def destroy_associations
-            association(:#{middle_reflection.name}).delete_all(:delete_all)
-            association(:#{name}).reset
-            super
-          end
-          RUBY
-        }
+          Builder::HasMany.define_callbacks self, middle_reflection
+          Reflection.add_reflection self, middle_reflection.name, middle_reflection
+          middle_reflection.parent_reflection = habtm_reflection
 
-        hm_options = {}
-        hm_options[:through] = middle_reflection.name
-        hm_options[:source] = join_model.right_reflection.name
+          include Module.new {
+            class_eval <<-RUBY, __FILE__, __LINE__ + 1
+              def destroy_associations
+                association(:#{middle_reflection.name}).delete_all(:delete_all)
+                association(:#{name}).reset
+                super
+              end
+            RUBY
+          }
 
-        [:before_add, :after_add, :before_remove, :after_remove, :autosave, :validate, :join_table, :class_name, :extend].each do |k|
-          hm_options[k] = options[k] if options.key? k
-        end
+          hm_options = {}
+          hm_options[:through] = middle_reflection.name
+          hm_options[:source] = join_model.right_reflection.name
 
-        has_many name, scope, hm_options, &extension
-        self._reflections[name.to_s].parent_reflection = habtm_reflection
+          [:before_add, :after_add, :before_remove, :after_remove, :autosave, :validate, :join_table, :class_name, :extend].each do |k|
+            hm_options[k] = options[k] if options.key? k
+          end
+
+          has_many name, scope, hm_options, &extension
+          _reflections[name.to_s].parent_reflection = habtm_reflection
+        end
       end
-    end
   end
 end
diff --git a/activerecord/lib/active_record/associations/alias_tracker.rb b/activerecord/lib/active_record/associations/alias_tracker.rb
index 021bc32237..14881cfe17 100644
--- a/activerecord/lib/active_record/associations/alias_tracker.rb
+++ b/activerecord/lib/active_record/associations/alias_tracker.rb
@@ -1,41 +1,39 @@
-require 'active_support/core_ext/string/conversions'
+# frozen_string_literal: true
+
+require "active_support/core_ext/string/conversions"
 
 module ActiveRecord
   module Associations
     # Keeps track of table aliases for ActiveRecord::Associations::JoinDependency
     class AliasTracker # :nodoc:
-      attr_reader :aliases
-
-      def self.create(connection, initial_table, type_caster)
-        aliases = Hash.new(0)
-        aliases[initial_table] = 1
-        new connection, aliases, type_caster
-      end
-
-      def self.create_with_joins(connection, initial_table, joins, type_caster)
+      def self.create(connection, initial_table, joins)
         if joins.empty?
-          create(connection, initial_table, type_caster)
+          aliases = Hash.new(0)
         else
           aliases = Hash.new { |h, k|
             h[k] = initial_count_for(connection, k, joins)
           }
-          aliases[initial_table] = 1
-          new connection, aliases, type_caster
         end
+        aliases[initial_table] = 1
+        new(connection, aliases)
       end
 
       def self.initial_count_for(connection, name, table_joins)
-        # quoted_name should be downcased as some database adapters (Oracle) return quoted name in uppercase
-        quoted_name = connection.quote_table_name(name).downcase
+        quoted_name = nil
 
         counts = table_joins.map do |join|
           if join.is_a?(Arel::Nodes::StringJoin)
+            # quoted_name should be case ignored as some database adapters (Oracle) return quoted name in uppercase
+            quoted_name ||= connection.quote_table_name(name)
+
             # Table names + table aliases
-            join.left.downcase.scan(
-              /join(?:\s+\w+)?\s+(\S+\s+)?#{quoted_name}\son/
+            join.left.scan(
+              /JOIN(?:\s+\w+)?\s+(?:\S+\s+)?(?:#{quoted_name}|#{name})\sON/i
             ).size
           elsif join.respond_to? :left
-            join.left.table_name == name ? 1 : 0
+            join.left.name == name ? 1 : 0
+          elsif join.is_a?(Hash)
+            join.fetch(name, 0)
           else
             # this branch is reached by two tests:
             #
@@ -53,17 +51,16 @@ module ActiveRecord
       end
 
       # table_joins is an array of arel joins which might conflict with the aliases we assign here
-      def initialize(connection, aliases, type_caster)
+      def initialize(connection, aliases)
         @aliases    = aliases
         @connection = connection
-        @type_caster = type_caster
       end
 
-      def aliased_table_for(table_name, aliased_name)
+      def aliased_table_for(table_name, aliased_name, type_caster)
         if aliases[table_name].zero?
           # If it's zero, we can have our table_name
           aliases[table_name] = 1
-          Arel::Table.new(table_name, type_caster: @type_caster)
+          Arel::Table.new(table_name, type_caster: type_caster)
         else
           # Otherwise, we need to use an alias
           aliased_name = @connection.table_alias_for(aliased_name)
@@ -76,10 +73,12 @@ module ActiveRecord
           else
             aliased_name
           end
-          Arel::Table.new(table_name, type_caster: @type_caster).alias(table_alias)
+          Arel::Table.new(table_name, type_caster: type_caster).alias(table_alias)
         end
       end
 
+      attr_reader :aliases
+
       private
 
         def truncate(name)
diff --git a/activerecord/lib/active_record/associations/association.rb b/activerecord/lib/active_record/associations/association.rb
index 62e867a353..ca1f9f1650 100644
--- a/activerecord/lib/active_record/associations/association.rb
+++ b/activerecord/lib/active_record/associations/association.rb
@@ -1,4 +1,6 @@
-require 'active_support/core_ext/array/wrap'
+# frozen_string_literal: true
+
+require "active_support/core_ext/array/wrap"
 
 module ActiveRecord
   module Associations
@@ -19,7 +21,7 @@ module ActiveRecord
       attr_reader :owner, :target, :reflection
       attr_accessor :inversed
 
-      delegate :options, :to => :reflection
+      delegate :options, to: :reflection
 
       def initialize(owner, reflection)
         reflection.check_validity!
@@ -30,14 +32,6 @@ module ActiveRecord
         reset_scope
       end
 
-      # Returns the name of the table of the associated class:
-      #
-      #   post.comments.aliased_table_name # => "comments"
-      #
-      def aliased_table_name
-        klass.table_name
-      end
-
       # Resets the \loaded flag to +false+ and sets the \target to +nil+.
       def reset
         @loaded = false
@@ -83,7 +77,7 @@ module ActiveRecord
       end
 
       def scope
-        target_scope.merge(association_scope)
+        target_scope.merge!(association_scope)
       end
 
       # The scope for this association.
@@ -94,7 +88,7 @@ module ActiveRecord
       # actually gets built.
       def association_scope
         if klass
-          @association_scope ||= AssociationScope.scope(self, klass.connection)
+          @association_scope ||= AssociationScope.scope(self)
         end
       end
 
@@ -112,6 +106,15 @@ module ActiveRecord
         record
       end
 
+      # Remove the inverse association, if possible
+      def remove_inverse_instance(record)
+        if invertible_for?(record)
+          inverse = record.association(inverse_reflection_for(record).name)
+          inverse.target = nil
+          inverse.inversed = false
+        end
+      end
+
       # Returns the class of the target. belongs_to polymorphic overrides this to look at the
       # polymorphic_type field on the owner.
       def klass
@@ -124,6 +127,16 @@ module ActiveRecord
         AssociationRelation.create(klass, klass.arel_table, klass.predicate_builder, self).merge!(klass.all)
       end
 
+      def extensions
+        extensions = klass.default_extensions | reflection.extensions
+
+        if reflection.scope
+          extensions |= reflection.scope_for(klass.unscoped, owner).extensions
+        end
+
+        extensions
+      end
+
       # Loads the \target if needed and returns it.
       #
       # This method is abstract in the sense that it relies on +find_target+,
@@ -143,14 +156,6 @@ module ActiveRecord
         reset
       end
 
-      def interpolate(sql, record = nil)
-        if sql.respond_to?(:to_proc)
-          owner.instance_exec(record, &sql)
-        else
-          sql
-        end
-      end
-
       # We can't dump @reflection since it contains the scope proc
       def marshal_dump
         ivars = (instance_variables - [:@reflection]).map { |name| [name, instance_variable_get(name)] }
@@ -166,14 +171,25 @@ module ActiveRecord
       def initialize_attributes(record, except_from_scope_attributes = nil) #:nodoc:
         except_from_scope_attributes ||= {}
         skip_assign = [reflection.foreign_key, reflection.type].compact
-        assigned_keys = record.changed
+        assigned_keys = record.changed_attribute_names_to_save
         assigned_keys += except_from_scope_attributes.keys.map(&:to_s)
-        attributes = create_scope.except(*(assigned_keys - skip_assign))
-        record.assign_attributes(attributes)
+        attributes = scope_for_create.except!(*(assigned_keys - skip_assign))
+        record.send(:_assign_attributes, attributes) if attributes.any?
         set_inverse_instance(record)
       end
 
+      def create(attributes = {}, &block)
+        _create_record(attributes, &block)
+      end
+
+      def create!(attributes = {}, &block)
+        _create_record(attributes, true, &block)
+      end
+
       private
+        def scope_for_create
+          scope.scope_for_create
+        end
 
         def find_target?
           !loaded? && (!owner.new_record? || foreign_key_present?) && klass
@@ -246,7 +262,7 @@ module ActiveRecord
         # so that when stale_state is different from the value stored on the last find_target,
         # the target is stale.
         #
-        # This is only relevant to certain associations, which is why it returns nil by default.
+        # This is only relevant to certain associations, which is why it returns +nil+ by default.
         def stale_state
         end
 
@@ -257,7 +273,7 @@ module ActiveRecord
         end
 
         # Returns true if statement cache should be skipped on the association reader.
-        def skip_statement_cache?
+        def skip_statement_cache?(scope)
           reflection.has_scope? ||
             scope.eager_loading? ||
             klass.scope_attributes? ||
diff --git a/activerecord/lib/active_record/associations/association_scope.rb b/activerecord/lib/active_record/associations/association_scope.rb
index 15844de0bc..11967e0571 100644
--- a/activerecord/lib/active_record/associations/association_scope.rb
+++ b/activerecord/lib/active_record/associations/association_scope.rb
@@ -1,8 +1,10 @@
+# frozen_string_literal: true
+
 module ActiveRecord
   module Associations
     class AssociationScope #:nodoc:
-      def self.scope(association, connection)
-        INSTANCE.scope(association, connection)
+      def self.scope(association)
+        INSTANCE.scope(association)
       end
 
       def self.create(&block)
@@ -16,20 +18,15 @@ module ActiveRecord
 
       INSTANCE = create
 
-      def scope(association, connection)
+      def scope(association)
         klass = association.klass
         reflection = association.reflection
         scope = klass.unscoped
         owner = association.owner
-        alias_tracker = AliasTracker.create connection, association.klass.table_name, klass.type_caster
-        chain_head, chain_tail = get_chain(reflection, association, alias_tracker)
-
-        scope.extending! Array(reflection.options[:extend])
-        add_constraints(scope, owner, klass, reflection, chain_head, chain_tail)
-      end
+        chain = get_chain(reflection, association, scope.alias_tracker)
 
-      def join_type
-        Arel::Nodes::InnerJoin
+        scope.extending! reflection.extensions
+        add_constraints(scope, owner, chain)
       end
 
       def self.get_bind_values(owner, chain)
@@ -49,117 +46,123 @@ module ActiveRecord
         binds
       end
 
+      # TODO Change this to private once we've dropped Ruby 2.2 support.
+      # Workaround for Ruby 2.2 "private attribute?" warning.
       protected
 
-      attr_reader :value_transformation
+        attr_reader :value_transformation
 
       private
-      def join(table, constraint)
-        table.create_join(table, table.create_on(constraint), join_type)
-      end
+        def join(table, constraint)
+          table.create_join(table, table.create_on(constraint))
+        end
+
+        def last_chain_scope(scope, reflection, owner)
+          join_keys = reflection.join_keys
+          key = join_keys.key
+          foreign_key = join_keys.foreign_key
 
-      def last_chain_scope(scope, table, reflection, owner, association_klass)
-        join_keys = reflection.join_keys(association_klass)
-        key = join_keys.key
-        foreign_key = join_keys.foreign_key
+          table = reflection.aliased_table
+          value = transform_value(owner[foreign_key])
+          scope = apply_scope(scope, table, key, value)
 
-        value = transform_value(owner[foreign_key])
-        scope = scope.where(table.name => { key => value })
+          if reflection.type
+            polymorphic_type = transform_value(owner.class.base_class.name)
+            scope = apply_scope(scope, table, reflection.type, polymorphic_type)
+          end
 
-        if reflection.type
-          polymorphic_type = transform_value(owner.class.base_class.name)
-          scope = scope.where(table.name => { reflection.type => polymorphic_type })
+          scope
         end
 
-        scope
-      end
+        def transform_value(value)
+          value_transformation.call(value)
+        end
 
-      def transform_value(value)
-        value_transformation.call(value)
-      end
+        def next_chain_scope(scope, reflection, next_reflection)
+          join_keys = reflection.join_keys
+          key = join_keys.key
+          foreign_key = join_keys.foreign_key
 
-      def next_chain_scope(scope, table, reflection, association_klass, foreign_table, next_reflection)
-        join_keys = reflection.join_keys(association_klass)
-        key = join_keys.key
-        foreign_key = join_keys.foreign_key
+          table = reflection.aliased_table
+          foreign_table = next_reflection.aliased_table
+          constraint = table[key].eq(foreign_table[foreign_key])
 
-        constraint = table[key].eq(foreign_table[foreign_key])
+          if reflection.type
+            value = transform_value(next_reflection.klass.base_class.name)
+            scope = apply_scope(scope, table, reflection.type, value)
+          end
 
-        if reflection.type
-          value = transform_value(next_reflection.klass.base_class.name)
-          scope = scope.where(table.name => { reflection.type => value })
+          scope.joins!(join(foreign_table, constraint))
         end
 
-        scope = scope.joins(join(foreign_table, constraint))
-      end
+        class ReflectionProxy < SimpleDelegator # :nodoc:
+          attr_reader :aliased_table
 
-      class ReflectionProxy < SimpleDelegator # :nodoc:
-        attr_accessor :next
-        attr_reader :alias_name
+          def initialize(reflection, aliased_table)
+            super(reflection)
+            @aliased_table = aliased_table
+          end
 
-        def initialize(reflection, alias_name)
-          super(reflection)
-          @alias_name = alias_name
+          def all_includes; nil; end
         end
 
-        def all_includes; nil; end
-      end
-
-      def get_chain(reflection, association, tracker)
-        name = reflection.name
-        runtime_reflection = Reflection::RuntimeReflection.new(reflection, association)
-        previous_reflection = runtime_reflection
-        reflection.chain.drop(1).each do |refl|
-          alias_name = tracker.aliased_table_for(refl.table_name, refl.alias_candidate(name))
-          proxy = ReflectionProxy.new(refl, alias_name)
-          previous_reflection.next = proxy
-          previous_reflection = proxy
+        def get_chain(reflection, association, tracker)
+          name = reflection.name
+          chain = [Reflection::RuntimeReflection.new(reflection, association)]
+          reflection.chain.drop(1).each do |refl|
+            aliased_table = tracker.aliased_table_for(
+              refl.table_name,
+              refl.alias_candidate(name),
+              refl.klass.type_caster
+            )
+            chain << ReflectionProxy.new(refl, aliased_table)
+          end
+          chain
         end
-        [runtime_reflection, previous_reflection]
-      end
-
-      def add_constraints(scope, owner, association_klass, refl, chain_head, chain_tail)
-        owner_reflection = chain_tail
-        table = owner_reflection.alias_name
-        scope = last_chain_scope(scope, table, owner_reflection, owner, association_klass)
 
-        reflection = chain_head
-        while reflection
-          table = reflection.alias_name
+        def add_constraints(scope, owner, chain)
+          scope = last_chain_scope(scope, chain.last, owner)
 
-          unless reflection == chain_tail
-            next_reflection = reflection.next
-            foreign_table = next_reflection.alias_name
-            scope = next_chain_scope(scope, table, reflection, association_klass, foreign_table, next_reflection)
+          chain.each_cons(2) do |reflection, next_reflection|
+            scope = next_chain_scope(scope, reflection, next_reflection)
           end
 
-          # Exclude the scope of the association itself, because that
-          # was already merged in the #scope method.
-          reflection.constraints.each do |scope_chain_item|
-            item  = eval_scope(reflection.klass, scope_chain_item, owner)
+          chain_head = chain.first
+          chain.reverse_each do |reflection|
+            # Exclude the scope of the association itself, because that
+            # was already merged in the #scope method.
+            reflection.constraints.each do |scope_chain_item|
+              item = eval_scope(reflection, scope_chain_item, owner)
 
-            if scope_chain_item == refl.scope
-              scope.merge! item.except(:where, :includes)
-            end
+              if scope_chain_item == chain_head.scope
+                scope.merge! item.except(:where, :includes)
+              end
 
-            reflection.all_includes do
-              scope.includes! item.includes_values
-            end
+              reflection.all_includes do
+                scope.includes! item.includes_values
+              end
 
-            scope.unscope!(*item.unscope_values)
-            scope.where_clause += item.where_clause
-            scope.order_values |= item.order_values
+              scope.unscope!(*item.unscope_values)
+              scope.where_clause += item.where_clause
+              scope.order_values |= item.order_values
+            end
           end
 
-          reflection = reflection.next
+          scope
         end
 
-        scope
-      end
+        def apply_scope(scope, table, key, value)
+          if scope.table == table
+            scope.where!(key => value)
+          else
+            scope.where!(table.name => { key => value })
+          end
+        end
 
-      def eval_scope(klass, scope, owner)
-        klass.unscoped.instance_exec(owner, &scope)
-      end
+        def eval_scope(reflection, scope, owner)
+          relation = reflection.build_scope(reflection.aliased_table)
+          relation.instance_exec(owner, &scope) || relation
+        end
     end
   end
 end
diff --git a/activerecord/lib/active_record/associations/belongs_to_association.rb b/activerecord/lib/active_record/associations/belongs_to_association.rb
index 24997370b2..bd2012df84 100644
--- a/activerecord/lib/active_record/associations/belongs_to_association.rb
+++ b/activerecord/lib/active_record/associations/belongs_to_association.rb
@@ -1,8 +1,9 @@
+# frozen_string_literal: true
+
 module ActiveRecord
-  # = Active Record Belongs To Association
   module Associations
+    # = Active Record Belongs To Association
     class BelongsToAssociation < SingularAssociation #:nodoc:
-
       def handle_dependency
         target.send(options[:dependent]) if load_target
       end
@@ -11,17 +12,24 @@ module ActiveRecord
         if record
           raise_on_type_mismatch!(record)
           update_counters_on_replace(record)
-          replace_keys(record)
           set_inverse_instance(record)
           @updated = true
         else
           decrement_counters
-          remove_keys
         end
 
         self.target = record
       end
 
+      def target=(record)
+        replace_keys(record)
+        super
+      end
+
+      def default(&block)
+        writer(owner.instance_exec(&block)) if reader.nil?
+      end
+
       def reset
         super
         @updated = false
@@ -44,9 +52,9 @@ module ActiveRecord
         def update_counters(by)
           if require_counter_update? && foreign_key_present?
             if target && !stale_target?
-              target.increment!(reflection.counter_cache_column, by)
+              target.increment!(reflection.counter_cache_column, by, touch: reflection.options[:touch])
             else
-              klass.update_counters(target_id, reflection.counter_cache_column => by)
+              klass.update_counters(target_id, reflection.counter_cache_column => by, touch: reflection.options[:touch])
             end
           end
         end
@@ -73,11 +81,8 @@ module ActiveRecord
         end
 
         def replace_keys(record)
-          owner[reflection.foreign_key] = record._read_attribute(reflection.association_primary_key(record.class))
-        end
-
-        def remove_keys
-          owner[reflection.foreign_key] = nil
+          owner[reflection.foreign_key] = record ?
+            record._read_attribute(reflection.association_primary_key(record.class)) : nil
         end
 
         def foreign_key_present?
diff --git a/activerecord/lib/active_record/associations/belongs_to_polymorphic_association.rb b/activerecord/lib/active_record/associations/belongs_to_polymorphic_association.rb
index b710cf6bdb..55d789c66a 100644
--- a/activerecord/lib/active_record/associations/belongs_to_polymorphic_association.rb
+++ b/activerecord/lib/active_record/associations/belongs_to_polymorphic_association.rb
@@ -1,6 +1,8 @@
+# frozen_string_literal: true
+
 module ActiveRecord
-  # = Active Record Belongs To Polymorphic Association
   module Associations
+    # = Active Record Belongs To Polymorphic Association
     class BelongsToPolymorphicAssociation < BelongsToAssociation #:nodoc:
       def klass
         type = owner[reflection.foreign_type]
@@ -11,12 +13,7 @@ module ActiveRecord
 
         def replace_keys(record)
           super
-          owner[reflection.foreign_type] = record.class.base_class.name
-        end
-
-        def remove_keys
-          super
-          owner[reflection.foreign_type] = nil
+          owner[reflection.foreign_type] = record ? record.class.base_class.name : nil
         end
 
         def different_target?(record)
diff --git a/activerecord/lib/active_record/associations/builder/association.rb b/activerecord/lib/active_record/associations/builder/association.rb
index d0534056d9..ca3032d967 100644
--- a/activerecord/lib/active_record/associations/builder/association.rb
+++ b/activerecord/lib/active_record/associations/builder/association.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 # This is the parent Association class which defines the variables
 # used by all associations.
 #
@@ -36,11 +38,6 @@ module ActiveRecord::Associations::Builder # :nodoc:
     def self.create_reflection(model, name, scope, options, extension = nil)
       raise ArgumentError, "association names must be a Symbol" unless name.kind_of?(Symbol)
 
-      if scope.is_a?(Hash)
-        options = scope
-        scope   = nil
-      end
-
       validate_options(options)
 
       scope = build_scope(scope, extension)
diff --git a/activerecord/lib/active_record/associations/builder/belongs_to.rb b/activerecord/lib/active_record/associations/builder/belongs_to.rb
index 3121e70a04..c161454c1a 100644
--- a/activerecord/lib/active_record/associations/builder/belongs_to.rb
+++ b/activerecord/lib/active_record/associations/builder/belongs_to.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActiveRecord::Associations::Builder # :nodoc:
   class BelongsTo < SingularAssociation #:nodoc:
     def self.macro
@@ -5,7 +7,7 @@ module ActiveRecord::Associations::Builder # :nodoc:
     end
 
     def self.valid_options(options)
-      super + [:polymorphic, :touch, :counter_cache, :optional]
+      super + [:polymorphic, :touch, :counter_cache, :optional, :default]
     end
 
     def self.valid_dependent_options
@@ -16,6 +18,7 @@ module ActiveRecord::Associations::Builder # :nodoc:
       super
       add_counter_cache_callbacks(model, reflection) if reflection.options[:counter_cache]
       add_touch_callbacks(model, reflection)         if reflection.options[:touch]
+      add_default_callbacks(model, reflection)       if reflection.options[:default]
     end
 
     def self.define_accessors(mixin, reflection)
@@ -31,21 +34,19 @@ module ActiveRecord::Associations::Builder # :nodoc:
           foreign_key  = reflection.foreign_key
           cache_column = reflection.counter_cache_column
 
-          if (@_after_create_counter_called ||= false)
-            @_after_create_counter_called = false
-          elsif (@_after_replace_counter_called ||= false)
+          if (@_after_replace_counter_called ||= false)
             @_after_replace_counter_called = false
-          elsif attribute_changed?(foreign_key) && !new_record?
+          elsif saved_change_to_attribute?(foreign_key) && !new_record?
             if reflection.polymorphic?
-              model     = attribute(reflection.foreign_type).try(:constantize)
-              model_was = attribute_was(reflection.foreign_type).try(:constantize)
+              model     = attribute_in_database(reflection.foreign_type).try(:constantize)
+              model_was = attribute_before_last_save(reflection.foreign_type).try(:constantize)
             else
               model     = reflection.klass
               model_was = reflection.klass
             end
 
-            foreign_key_was = attribute_was foreign_key
-            foreign_key     = attribute foreign_key
+            foreign_key_was = attribute_before_last_save foreign_key
+            foreign_key     = attribute_in_database foreign_key
 
             if foreign_key && model.respond_to?(:increment_counter)
               model.increment_counter(cache_column, foreign_key)
@@ -70,14 +71,16 @@ module ActiveRecord::Associations::Builder # :nodoc:
       klass.attr_readonly cache_column if klass && klass.respond_to?(:attr_readonly)
     end
 
-    def self.touch_record(o, foreign_key, name, touch, touch_method) # :nodoc:
-      old_foreign_id = o.changed_attributes[foreign_key]
+    def self.touch_record(o, changes, foreign_key, name, touch, touch_method) # :nodoc:
+      old_foreign_id = changes[foreign_key] && changes[foreign_key].first
 
       if old_foreign_id
         association = o.association(name)
         reflection = association.reflection
         if reflection.polymorphic?
-          klass = o.public_send("#{reflection.foreign_type}_was").constantize
+          foreign_type = reflection.foreign_type
+          klass = changes[foreign_type] && changes[foreign_type].first || o.public_send(foreign_type)
+          klass = klass.constantize
         else
           klass = association.klass
         end
@@ -107,13 +110,23 @@ module ActiveRecord::Associations::Builder # :nodoc:
       n           = reflection.name
       touch       = reflection.options[:touch]
 
-      callback = lambda { |record|
-        BelongsTo.touch_record(record, foreign_key, n, touch, belongs_to_touch_method)
-      }
+      callback = lambda { |changes_method| lambda { |record|
+        BelongsTo.touch_record(record, record.send(changes_method), foreign_key, n, touch, belongs_to_touch_method)
+      }}
+
+      unless reflection.counter_cache_column
+        model.after_create callback.(:saved_changes), if: :saved_changes?
+        model.after_destroy callback.(:changes_to_save)
+      end
 
-      model.after_save    callback, if: :changed?
-      model.after_touch   callback
-      model.after_destroy callback
+      model.after_update callback.(:saved_changes), if: :saved_changes?
+      model.after_touch callback.(:changes_to_save)
+    end
+
+    def self.add_default_callbacks(model, reflection)
+      model.before_validation lambda { |o|
+        o.association(reflection.name).default(&reflection.options[:default])
+      }
     end
 
     def self.add_destroy_callbacks(model, reflection)
diff --git a/activerecord/lib/active_record/associations/builder/collection_association.rb b/activerecord/lib/active_record/associations/builder/collection_association.rb
index f25bd7ca9f..35a72c3850 100644
--- a/activerecord/lib/active_record/associations/builder/collection_association.rb
+++ b/activerecord/lib/active_record/associations/builder/collection_association.rb
@@ -1,10 +1,9 @@
-# This class is inherited by the has_many and has_many_and_belongs_to_many association classes
+# frozen_string_literal: true
 
-require 'active_record/associations'
+require "active_record/associations"
 
 module ActiveRecord::Associations::Builder # :nodoc:
   class CollectionAssociation < Association #:nodoc:
-
     CALLBACKS = [:before_add, :after_add, :before_remove, :after_remove]
 
     def self.valid_options(options)
diff --git a/activerecord/lib/active_record/associations/builder/has_and_belongs_to_many.rb b/activerecord/lib/active_record/associations/builder/has_and_belongs_to_many.rb
index 5fbd79d118..1981da11a2 100644
--- a/activerecord/lib/active_record/associations/builder/has_and_belongs_to_many.rb
+++ b/activerecord/lib/active_record/associations/builder/has_and_belongs_to_many.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActiveRecord::Associations::Builder # :nodoc:
   class HasAndBelongsToMany # :nodoc:
     class JoinTableResolver # :nodoc:
@@ -16,9 +18,9 @@ module ActiveRecord::Associations::Builder # :nodoc:
 
         private
 
-        def klass
-          @lhs_class.send(:compute_type, @rhs_class_name)
-        end
+          def klass
+            @lhs_class.send(:compute_type, @rhs_class_name)
+          end
       end
 
       def self.build(lhs_class, name, options)
@@ -28,7 +30,7 @@ module ActiveRecord::Associations::Builder # :nodoc:
           class_name = options.fetch(:class_name) {
             name.to_s.camelize.singularize
           }
-          KnownClass.new lhs_class, class_name
+          KnownClass.new lhs_class, class_name.to_s
         end
       end
     end
@@ -45,7 +47,7 @@ module ActiveRecord::Associations::Builder # :nodoc:
       habtm = JoinTableResolver.build lhs_model, association_name, options
 
       join_model = Class.new(ActiveRecord::Base) {
-        class << self;
+        class << self
           attr_accessor :left_model
           attr_accessor :name
           attr_accessor :table_name_resolver
@@ -76,9 +78,11 @@ module ActiveRecord::Associations::Builder # :nodoc:
           left_model.retrieve_connection
         end
 
-        def self.primary_key
-          false
-        end
+        private
+
+          def self.suppress_composite_primary_key(pk)
+            pk unless pk.is_a?(Array)
+          end
       }
 
       join_model.name                = "HABTM_#{association_name.to_s.camelize}"
@@ -92,7 +96,7 @@ module ActiveRecord::Associations::Builder # :nodoc:
 
     def middle_reflection(join_model)
       middle_name = [lhs_model.name.downcase.pluralize,
-                     association_name].join('_'.freeze).gsub('::'.freeze, '_'.freeze).to_sym
+                     association_name].join("_".freeze).gsub("::".freeze, "_".freeze).to_sym
       middle_options = middle_options join_model
 
       HasMany.create_reflection(lhs_model,
@@ -103,29 +107,29 @@ module ActiveRecord::Associations::Builder # :nodoc:
 
     private
 
-    def middle_options(join_model)
-      middle_options = {}
-      middle_options[:class_name] = "#{lhs_model.name}::#{join_model.name}"
-      middle_options[:source] = join_model.left_reflection.name
-      if options.key? :foreign_key
-        middle_options[:foreign_key] = options[:foreign_key]
+      def middle_options(join_model)
+        middle_options = {}
+        middle_options[:class_name] = "#{lhs_model.name}::#{join_model.name}"
+        middle_options[:source] = join_model.left_reflection.name
+        if options.key? :foreign_key
+          middle_options[:foreign_key] = options[:foreign_key]
+        end
+        middle_options
       end
-      middle_options
-    end
 
-    def belongs_to_options(options)
-      rhs_options = {}
+      def belongs_to_options(options)
+        rhs_options = {}
 
-      if options.key? :class_name
-        rhs_options[:foreign_key] = options[:class_name].to_s.foreign_key
-        rhs_options[:class_name] = options[:class_name]
-      end
+        if options.key? :class_name
+          rhs_options[:foreign_key] = options[:class_name].to_s.foreign_key
+          rhs_options[:class_name] = options[:class_name]
+        end
 
-      if options.key? :association_foreign_key
-        rhs_options[:foreign_key] = options[:association_foreign_key]
-      end
+        if options.key? :association_foreign_key
+          rhs_options[:foreign_key] = options[:association_foreign_key]
+        end
 
-      rhs_options
-    end
+        rhs_options
+      end
   end
 end
diff --git a/activerecord/lib/active_record/associations/builder/has_many.rb b/activerecord/lib/active_record/associations/builder/has_many.rb
index 7864d4c536..5b9617bc6d 100644
--- a/activerecord/lib/active_record/associations/builder/has_many.rb
+++ b/activerecord/lib/active_record/associations/builder/has_many.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActiveRecord::Associations::Builder # :nodoc:
   class HasMany < CollectionAssociation #:nodoc:
     def self.macro
diff --git a/activerecord/lib/active_record/associations/builder/has_one.rb b/activerecord/lib/active_record/associations/builder/has_one.rb
index 4de846d12b..bfb37d6eee 100644
--- a/activerecord/lib/active_record/associations/builder/has_one.rb
+++ b/activerecord/lib/active_record/associations/builder/has_one.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActiveRecord::Associations::Builder # :nodoc:
   class HasOne < SingularAssociation #:nodoc:
     def self.macro
diff --git a/activerecord/lib/active_record/associations/builder/singular_association.rb b/activerecord/lib/active_record/associations/builder/singular_association.rb
index bb96202a22..0a02ef4cc1 100644
--- a/activerecord/lib/active_record/associations/builder/singular_association.rb
+++ b/activerecord/lib/active_record/associations/builder/singular_association.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 # This class is inherited by the has_one and belongs_to association classes
 
 module ActiveRecord::Associations::Builder # :nodoc:
@@ -8,7 +10,16 @@ module ActiveRecord::Associations::Builder # :nodoc:
 
     def self.define_accessors(model, reflection)
       super
-      define_constructors(model.generated_association_methods, reflection.name) if reflection.constructable?
+      mixin = model.generated_association_methods
+      name = reflection.name
+
+      define_constructors(mixin, name) if reflection.constructable?
+
+      mixin.class_eval <<-CODE, __FILE__, __LINE__ + 1
+        def reload_#{name}
+          association(:#{name}).force_reload_reader
+        end
+      CODE
     end
 
     # Defines the (build|create)_association methods for belongs_to or has_one association
diff --git a/activerecord/lib/active_record/associations/collection_association.rb b/activerecord/lib/active_record/associations/collection_association.rb
index 0eaa0a4f36..de8afc9ccb 100644
--- a/activerecord/lib/active_record/associations/collection_association.rb
+++ b/activerecord/lib/active_record/associations/collection_association.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActiveRecord
   module Associations
     # = Active Record Association Collection
@@ -24,28 +26,14 @@ module ActiveRecord
     # If you need to work on all current children, new and existing records,
     # +load_target+ and the +loaded+ flag are your friends.
     class CollectionAssociation < Association #:nodoc:
-
       # Implements the reader method, e.g. foo.items for Foo.has_many :items
-      def reader(force_reload = false)
-        if force_reload
-          ActiveSupport::Deprecation.warn(<<-MSG.squish)
-            Passing an argument to force an association to reload is now
-            deprecated and will be removed in Rails 5.1. Please call `reload`
-            on the result collection proxy instead.
-          MSG
-
-          klass.uncached { reload }
-        elsif stale_target?
+      def reader
+        if stale_target?
           reload
         end
 
-        if null_scope?
-          # Cache the proxy separately before the owner has an id
-          # or else a post-save proxy will still lack the id
-          @null_proxy ||= CollectionProxy.create(klass, self)
-        else
-          @proxy ||= CollectionProxy.create(klass, self)
-        end
+        @proxy ||= CollectionProxy.create(klass, self)
+        @proxy.reset_scope
       end
 
       # Implements the writer method, e.g. foo.items= for Foo.has_many :items
@@ -56,105 +44,58 @@ module ActiveRecord
       # Implements the ids reader method, e.g. foo.item_ids for Foo.has_many :items
       def ids_reader
         if loaded?
-          load_target.map do |record|
-            record.send(reflection.association_primary_key)
-          end
+          target.pluck(reflection.association_primary_key)
         else
-          @association_ids ||= (
-            column = "#{reflection.quoted_table_name}.#{reflection.association_primary_key}"
-            scope.pluck(column)
-          )
+          @association_ids ||= scope.pluck(reflection.association_primary_key)
         end
       end
 
       # Implements the ids writer method, e.g. foo.item_ids= for Foo.has_many :items
       def ids_writer(ids)
-        pk_type = reflection.primary_key_type
+        primary_key = reflection.association_primary_key
+        pk_type = klass.type_for_attribute(primary_key.to_s)
         ids = Array(ids).reject(&:blank?)
         ids.map! { |i| pk_type.cast(i) }
-        records = klass.where(reflection.association_primary_key => ids).index_by do |r|
-          r.send(reflection.association_primary_key)
-        end.values_at(*ids)
-        replace(records)
-      end
 
-      def reset
-        super
-        @target = []
-      end
-
-      def select(*fields)
-        if block_given?
-          load_target.select.each { |e| yield e }
-        else
-          scope.select(*fields)
-        end
-      end
+        records = klass.where(primary_key => ids).index_by do |r|
+          r.public_send(primary_key)
+        end.values_at(*ids).compact
 
-      def find(*args)
-        if block_given?
-          load_target.find(*args) { |*block_args| yield(*block_args) }
+        if records.size != ids.size
+          found_ids = records.map { |record| record.public_send(primary_key) }
+          not_found_ids = ids - found_ids
+          klass.all.raise_record_not_found_exception!(ids, records.size, ids.size, primary_key, not_found_ids)
         else
-          if options[:inverse_of] && loaded?
-            args_flatten = args.flatten
-            raise RecordNotFound, "Couldn't find #{scope.klass.name} without an ID" if args_flatten.blank?
-            result = find_by_scan(*args)
-
-            result_size = Array(result).size
-            if !result || result_size != args_flatten.size
-              scope.raise_record_not_found_exception!(args_flatten, result_size, args_flatten.size)
-            else
-              result
-            end
-          else
-            scope.find(*args)
-          end
+          replace(records)
         end
       end
 
-      def first(*args)
-        first_nth_or_last(:first, *args)
-      end
-
-      def second(*args)
-        first_nth_or_last(:second, *args)
-      end
-
-      def third(*args)
-        first_nth_or_last(:third, *args)
-      end
-
-      def fourth(*args)
-        first_nth_or_last(:fourth, *args)
-      end
-
-      def fifth(*args)
-        first_nth_or_last(:fifth, *args)
-      end
-
-      def forty_two(*args)
-        first_nth_or_last(:forty_two, *args)
+      def reset
+        super
+        @target = []
+        @association_ids = nil
       end
 
-      def third_to_last(*args)
-        first_nth_or_last(:third_to_last, *args)
-      end
+      def find(*args)
+        if options[:inverse_of] && loaded?
+          args_flatten = args.flatten
+          model = scope.klass
 
-      def second_to_last(*args)
-        first_nth_or_last(:second_to_last, *args)
-      end
+          if args_flatten.blank?
+            error_message = "Couldn't find #{model.name} without an ID"
+            raise RecordNotFound.new(error_message, model.name, model.primary_key, args)
+          end
 
-      def last(*args)
-        first_nth_or_last(:last, *args)
-      end
+          result = find_by_scan(*args)
 
-      def take(n = nil)
-        if loaded?
-          n ? target.take(n) : target.first
-        else
-          scope.take(n).tap do |record|
-            set_inverse_instance record if record.is_a? ActiveRecord::Base
+          result_size = Array(result).size
+          if !result || result_size != args_flatten.size
+            scope.raise_record_not_found_exception!(args_flatten, result_size, args_flatten.size)
+          else
+            result
           end
+        else
+          scope.find(*args)
         end
       end
 
@@ -168,14 +109,6 @@ module ActiveRecord
         end
       end
 
-      def create(attributes = {}, &block)
-        _create_record(attributes, &block)
-      end
-
-      def create!(attributes = {}, &block)
-        _create_record(attributes, true, &block)
-      end
-
       # Add +records+ to this association. Returns +self+ so method calls may
       # be chained. Since << flattens its argument list and inserts each record,
       # +push+ and +concat+ behave identically.
@@ -223,12 +156,12 @@ module ActiveRecord
         end
 
         dependent = if dependent
-                      dependent
-                    elsif options[:dependent] == :destroy
-                      :delete_all
-                    else
-                      options[:dependent]
-                    end
+          dependent
+        elsif options[:dependent] == :destroy
+          :delete_all
+        else
+          options[:dependent]
+        end
 
         delete_or_nullify_all_records(dependent).tap do
           reset
@@ -246,31 +179,6 @@ module ActiveRecord
         end
       end
 
-      # Returns the number of records. If no arguments are given, it counts all
-      # columns using SQL. If one argument is given, it counts only the passed
-      # column using SQL. If a block is given, it counts the number of records
-      # yielding a true value.
-      def count(column_name = nil)
-        return super if block_given?
-        relation = scope
-        if association_scope.distinct_value
-          # This is needed because 'SELECT count(DISTINCT *)..' is not valid SQL.
-          column_name ||= reflection.klass.primary_key
-          relation = relation.distinct
-        end
-
-        value = relation.count(column_name)
-
-        limit  = options[:limit]
-        offset = options[:offset]
-
-        if limit || offset
-          [ [value - offset.to_i, 0].max, limit.to_i ].min
-        else
-          value
-        end
-      end
-
       # Removes +records+ from this association calling +before_remove+ and
       # +after_remove+ callbacks.
       #
@@ -279,12 +187,7 @@ module ActiveRecord
       # are actually removed from the database, that depends precisely on
       # +delete_records+. They are in any case removed from the collection.
       def delete(*records)
-        return if records.empty?
-        _options = records.extract_options!
-        dependent = _options[:dependent] || options[:dependent]
-
-        records = find(records) if records.any? { |record| record.kind_of?(Integer) || record.kind_of?(String) }
-        delete_or_destroy(records, dependent)
+        delete_or_destroy(records, options[:dependent])
       end
 
       # Deletes the +records+ and removes them from this association calling
@@ -293,8 +196,6 @@ module ActiveRecord
       # Note that this method removes records from the database ignoring the
       # +:dependent+ option.
       def destroy(*records)
-        return if records.empty?
-        records = find(records) if records.any? { |record| record.kind_of?(Integer) || record.kind_of?(String) }
         delete_or_destroy(records, :destroy)
       end
 
@@ -310,14 +211,10 @@ module ActiveRecord
       # +count_records+, which is a method descendants have to provide.
       def size
         if !find_target? || loaded?
-          if association_scope.distinct_value
-            target.uniq.size
-          else
-            target.size
-          end
-        elsif !loaded? && !association_scope.group_values.empty?
+          target.size
+        elsif !association_scope.group_values.empty?
           load_target.size
-        elsif !loaded? && !association_scope.distinct_value && target.is_a?(Array)
+        elsif !association_scope.distinct_value && target.is_a?(Array)
           unsaved_records = target.select(&:new_record?)
           unsaved_records.size + count_records
         else
@@ -325,15 +222,6 @@ module ActiveRecord
         end
       end
 
-      # Returns the size of the collection calling +size+ on the target.
-      #
-      # If the collection has been already loaded +length+ and +size+ are
-      # equivalent. If not and you are going to need the records anyway this
-      # method will take one less query. Otherwise +size+ is more efficient.
-      def length
-        load_target.size
-      end
-
       # Returns true if the collection is empty.
       #
       # If the collection has been loaded
@@ -350,36 +238,6 @@ module ActiveRecord
         end
       end
 
-      # Returns true if the collections is not empty.
-      # If block given, loads all records and checks for one or more matches.
-      # Otherwise, equivalent to +!collection.empty?+.
-      def any?
-        if block_given?
-          load_target.any? { |*block_args| yield(*block_args) }
-        else
-          !empty?
-        end
-      end
-
-      # Returns true if the collection has more than 1 record.
-      # If block given, loads all records and checks for two or more matches.
-      # Otherwise, equivalent to +collection.size > 1+.
-      def many?
-        if block_given?
-          load_target.many? { |*block_args| yield(*block_args) }
-        else
-          size > 1
-        end
-      end
-
-      def distinct
-        seen = {}
-        load_target.find_all do |record|
-          seen[record.id] = true unless seen.key?(record.id)
-        end
-      end
-      alias uniq distinct
-
       # Replace this collection with +other_array+. This will perform a diff
       # and delete/add only records that have changed.
       def replace(other_array)
@@ -426,29 +284,9 @@ module ActiveRecord
         replace_on_target(record, index, skip_callbacks, &block)
       end
 
-      def replace_on_target(record, index, skip_callbacks)
-        callback(:before_add, record) unless skip_callbacks
-
-        was_loaded = loaded?
-        yield(record) if block_given?
-
-        unless !was_loaded && loaded?
-          if index
-            @target[index] = record
-          else
-            @target << record
-          end
-        end
-
-        callback(:after_add, record) unless skip_callbacks
-        set_inverse_instance(record)
-
-        record
-      end
-
-      def scope(opts = {})
-        scope = super()
-        scope.none! if opts.fetch(:nullify, true) && null_scope?
+      def scope
+        scope = super
+        scope.none! if null_scope?
         scope
       end
 
@@ -456,26 +294,28 @@ module ActiveRecord
         owner.new_record? && !foreign_key_present?
       end
 
+      def find_from_target?
+        loaded? ||
+          owner.new_record? ||
+          target.any? { |record| record.new_record? || record.changed? }
+      end
+
       private
-      def get_records
-        return scope.to_a if skip_statement_cache?
 
-        conn = klass.connection
-        sc = reflection.association_scope_cache(conn, owner) do
-          StatementCache.create(conn) { |params|
-            as = AssociationScope.create { params.bind }
-            target_scope.merge as.scope(self, conn)
-          }
-        end
+        def find_target
+          scope = self.scope
+          return scope.to_a if skip_statement_cache?(scope)
 
-        binds = AssociationScope.get_bind_values(owner, reflection.chain)
-        sc.execute binds, klass, klass.connection
-      end
+          conn = klass.connection
+          sc = reflection.association_scope_cache(conn, owner) do |params|
+            as = AssociationScope.create { params.bind }
+            target_scope.merge!(as.scope(self))
+          end
 
-        def find_target
-          records = get_records
-          records.each { |record| set_inverse_instance(record) }
-          records
+          binds = AssociationScope.get_bind_values(owner, reflection.chain)
+          sc.execute(binds, conn) do |record|
+            set_inverse_instance(record)
+          end
         end
 
         # We have some records loaded from the database (persisted) and some that are
@@ -495,7 +335,7 @@ module ActiveRecord
           persisted.map! do |record|
             if mem_record = memory.delete(record)
 
-              ((record.attribute_names & mem_record.attribute_names) - mem_record.changes.keys).each do |name|
+              ((record.attribute_names & mem_record.attribute_names) - mem_record.changed_attribute_names_to_save).each do |name|
                 mem_record[name] = record[name]
               end
 
@@ -519,22 +359,27 @@ module ActiveRecord
             transaction do
               add_to_target(build_record(attributes)) do |record|
                 yield(record) if block_given?
-                insert_record(record, true, raise)
+                insert_record(record, true, raise) {
+                  @_was_loaded = loaded?
+                  @association_ids = nil
+                }
               end
             end
           end
         end
 
         # Do the relevant stuff to insert the given record into the association collection.
-        def insert_record(record, validate = true, raise = false)
-          raise NotImplementedError
-        end
-
-        def create_scope
-          scope.scope_for_create.stringify_keys
+        def insert_record(record, validate = true, raise = false, &block)
+          if raise
+            record.save!(validate: validate, &block)
+          else
+            record.save(validate: validate, &block)
+          end
         end
 
         def delete_or_destroy(records, method)
+          return if records.empty?
+          records = find(records) if records.any? { |record| record.kind_of?(Integer) || record.kind_of?(String) }
           records = records.flatten
           records.each { |record| raise_on_type_mismatch!(record) }
           existing_records = records.reject(&:new_record?)
@@ -555,8 +400,9 @@ module ActiveRecord
           records.each { |record| callback(:after_remove, record) }
         end
 
-        # Delete the given records from the association, using one of the methods :destroy,
-        # :delete_all or :nullify (or nil, in which case a default is used).
+        # Delete the given records from the association,
+        # using one of the methods +:destroy+, +:delete_all+
+        # or +:nullify+ (or +nil+, in which case a default is used).
         def delete_records(records, method)
           raise NotImplementedError
         end
@@ -581,19 +427,46 @@ module ActiveRecord
           end
         end
 
-        def concat_records(records, should_raise = false)
+        def concat_records(records, raise = false)
           result = true
 
           records.each do |record|
             raise_on_type_mismatch!(record)
-            add_to_target(record) do |rec|
-              result &&= insert_record(rec, true, should_raise) unless owner.new_record?
+            add_to_target(record) do
+              unless owner.new_record?
+                result &&= insert_record(record, true, raise) {
+                  @_was_loaded = loaded?
+                  @association_ids = nil
+                }
+              end
             end
           end
 
           result && records
         end
 
+        def replace_on_target(record, index, skip_callbacks)
+          callback(:before_add, record) unless skip_callbacks
+
+          set_inverse_instance(record)
+
+          @_was_loaded = true
+
+          yield(record) if block_given?
+
+          if index
+            target[index] = record
+          elsif @_was_loaded || !loaded?
+            target << record
+          end
+
+          callback(:after_add, record) unless skip_callbacks
+
+          record
+        ensure
+          @_was_loaded = nil
+        end
+
         def callback(method, record)
           callbacks_for(method).each do |callback|
             callback.call(method, owner, record)
@@ -605,25 +478,6 @@ module ActiveRecord
           owner.class.send(full_callback_name)
         end
 
-        # Should we deal with assoc.first or assoc.last by issuing an independent query to
-        # the database, or by getting the target, and then taking the first/last item from that?
-        #
-        # If the args is just a non-empty options hash, go to the database.
-        #
-        # Otherwise, go to the database only if none of the following are true:
-        #   * target already loaded
-        #   * owner is new record
-        #   * target contains new or changed record(s)
-        def fetch_first_nth_or_last_using_find?(args)
-          if args.first.is_a?(Hash)
-            true
-          else
-            !(loaded? ||
-              owner.new_record? ||
-              target.any? { |record| record.new_record? || record.changed? })
-          end
-        end
-
         def include_in_memory?(record)
           if reflection.is_a?(ActiveRecord::Reflection::ThroughReflection)
             assoc = owner.association(reflection.through_reflection.name)
@@ -650,16 +504,6 @@ module ActiveRecord
             load_target.select { |r| ids.include?(r.id.to_s) }
           end
         end
-
-        # Fetches the first/last using SQL if possible, otherwise from the target array.
-        def first_nth_or_last(type, *args)
-          args.shift if args.first.is_a?(Hash) && args.first.empty?
-
-          collection = fetch_first_nth_or_last_using_find?(args) ? scope : load_target
-          collection.send(type, *args).tap do |record|
-            set_inverse_instance record if record.is_a? ActiveRecord::Base
-          end
-        end
     end
   end
 end
diff --git a/activerecord/lib/active_record/associations/collection_proxy.rb b/activerecord/lib/active_record/associations/collection_proxy.rb
index 5d1e7ffb73..8b4a48a38c 100644
--- a/activerecord/lib/active_record/associations/collection_proxy.rb
+++ b/activerecord/lib/active_record/associations/collection_proxy.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActiveRecord
   module Associations
     # Association proxies in Active Record are middlemen between the object that
@@ -28,13 +30,12 @@ module ActiveRecord
     # is computed directly through SQL and does not trigger by itself the
     # instantiation of the actual post records.
     class CollectionProxy < Relation
-      delegate(*(ActiveRecord::Calculations.public_instance_methods - [:count]), to: :scope)
-      delegate :find_nth, to: :scope
-
       def initialize(klass, association) #:nodoc:
         @association = association
         super klass, klass.arel_table, klass.predicate_builder
-        merge! association.scope(nullify: false)
+
+        extensions = association.extensions
+        extend(*extensions) if extensions.any?
       end
 
       def target
@@ -54,6 +55,12 @@ module ActiveRecord
         @association.loaded?
       end
 
+      ##
+      # :method: select
+      #
+      # :call-seq:
+      #   select(*fields, &block)
+      #
       # Works in two ways.
       #
       # *First:* Specify a subset of fields to be selected from the result set.
@@ -76,7 +83,7 @@ module ActiveRecord
       #   #      #<Pet id: nil, name: "Choo-Choo">
       #   #    ]
       #
-      #   person.pets.select(:id, :name )
+      #   person.pets.select(:id, :name)
       #   # => [
       #   #      #<Pet id: 1, name: "Fancy-Fancy">,
       #   #      #<Pet id: 2, name: "Spook">,
@@ -101,15 +108,6 @@ module ActiveRecord
       #   #      #<Pet id: 2, name: "Spook", person_id: 1>,
       #   #      #<Pet id: 3, name: "Choo-Choo", person_id: 1>
       #   #    ]
-      #
-      #   person.pets.select(:name) { |pet| pet.name =~ /oo/ }
-      #   # => [
-      #   #      #<Pet id: 2, name: "Spook">,
-      #   #      #<Pet id: 3, name: "Choo-Choo">
-      #   #    ]
-      def select(*fields, &block)
-        @association.select(*fields, &block)
-      end
 
       # Finds an object in the collection responding to the +id+. Uses the same
       # rules as ActiveRecord::Base.find. Returns ActiveRecord::RecordNotFound
@@ -137,10 +135,17 @@ module ActiveRecord
       #   #       #<Pet id: 2, name: "Spook", person_id: 1>,
       #   #       #<Pet id: 3, name: "Choo-Choo", person_id: 1>
       #   #    ]
-      def find(*args, &block)
-        @association.find(*args, &block)
+      def find(*args)
+        return super if block_given?
+        @association.find(*args)
       end
 
+      ##
+      # :method: first
+      #
+      # :call-seq:
+      #   first(limit = nil)
+      #
       # Returns the first record, or the first +n+ records, from the collection.
       # If the collection is empty, the first form returns +nil+, and the second
       # form returns an empty array.
@@ -167,45 +172,63 @@ module ActiveRecord
       #   another_person_without.pets          # => []
       #   another_person_without.pets.first    # => nil
       #   another_person_without.pets.first(3) # => []
-      def first(*args)
-        @association.first(*args)
-      end
 
+      ##
+      # :method: second
+      #
+      # :call-seq:
+      #   second()
+      #
       # Same as #first except returns only the second record.
-      def second(*args)
-        @association.second(*args)
-      end
 
+      ##
+      # :method: third
+      #
+      # :call-seq:
+      #   third()
+      #
       # Same as #first except returns only the third record.
-      def third(*args)
-        @association.third(*args)
-      end
 
+      ##
+      # :method: fourth
+      #
+      # :call-seq:
+      #   fourth()
+      #
       # Same as #first except returns only the fourth record.
-      def fourth(*args)
-        @association.fourth(*args)
-      end
 
+      ##
+      # :method: fifth
+      #
+      # :call-seq:
+      #   fifth()
+      #
       # Same as #first except returns only the fifth record.
-      def fifth(*args)
-        @association.fifth(*args)
-      end
 
+      ##
+      # :method: forty_two
+      #
+      # :call-seq:
+      #   forty_two()
+      #
       # Same as #first except returns only the forty second record.
       # Also known as accessing "the reddit".
-      def forty_two(*args)
-        @association.forty_two(*args)
-      end
 
+      ##
+      # :method: third_to_last
+      #
+      # :call-seq:
+      #   third_to_last()
+      #
       # Same as #first except returns only the third-to-last record.
-      def third_to_last(*args)
-        @association.third_to_last(*args)
-      end
 
+      ##
+      # :method: second_to_last
+      #
+      # :call-seq:
+      #   second_to_last()
+      #
       # Same as #first except returns only the second-to-last record.
-      def second_to_last(*args)
-        @association.second_to_last(*args)
-      end
 
       # Returns the last record, or the last +n+ records, from the collection.
       # If the collection is empty, the first form returns +nil+, and the second
@@ -233,8 +256,9 @@ module ActiveRecord
       #   another_person_without.pets         # => []
       #   another_person_without.pets.last    # => nil
       #   another_person_without.pets.last(3) # => []
-      def last(*args)
-        @association.last(*args)
+      def last(limit = nil)
+        load_target if find_from_target?
+        super
       end
 
       # Gives a record (or N records if a parameter is supplied) from the collection
@@ -262,8 +286,9 @@ module ActiveRecord
       #   another_person_without.pets         # => []
       #   another_person_without.pets.take    # => nil
       #   another_person_without.pets.take(2) # => []
-      def take(n = nil)
-        @association.take(n)
+      def take(limit = nil)
+        load_target if find_from_target?
+        super
       end
 
       # Returns a new object of the collection type that has been instantiated
@@ -696,6 +721,12 @@ module ActiveRecord
         @association.destroy(*records)
       end
 
+      ##
+      # :method: distinct
+      #
+      # :call-seq:
+      #   distinct(value = true)
+      #
       # Specifies whether the records should be unique or not.
       #
       #   class Person < ActiveRecord::Base
@@ -710,11 +741,28 @@ module ActiveRecord
       #
       #   person.pets.select(:name).distinct
       #   # => [#<Pet name: "Fancy-Fancy">]
-      def distinct
-        @association.distinct
+      #
+      #   person.pets.select(:name).distinct.distinct(false)
+      #   # => [
+      #   #      #<Pet name: "Fancy-Fancy">,
+      #   #      #<Pet name: "Fancy-Fancy">
+      #   #    ]
+
+      #--
+      def calculate(operation, column_name)
+        null_scope? ? scope.calculate(operation, column_name) : super
+      end
+
+      def pluck(*column_names)
+        null_scope? ? scope.pluck(*column_names) : super
       end
-      alias uniq distinct
 
+      ##
+      # :method: count
+      #
+      # :call-seq:
+      #   count(column_name = nil, &block)
+      #
       # Count all records.
       #
       #   class Person < ActiveRecord::Base
@@ -734,9 +782,6 @@ module ActiveRecord
       # perform the count using Ruby.
       #
       #   person.pets.count { |pet| pet.name.include?('-') } # => 2
-      def count(column_name = nil, &block)
-        @association.count(column_name, &block)
-      end
 
       # Returns the size of the collection. If the collection hasn't been loaded,
       # it executes a <tt>SELECT COUNT(*)</tt> query. Else it calls <tt>collection.size</tt>.
@@ -766,6 +811,12 @@ module ActiveRecord
         @association.size
       end
 
+      ##
+      # :method: length
+      #
+      # :call-seq:
+      #   length()
+      #
       # Returns the size of the collection calling +size+ on the target.
       # If the collection has been already loaded, +length+ and +size+ are
       # equivalent. If not and you are going to need the records anyway this
@@ -786,14 +837,11 @@ module ActiveRecord
       #   #       #<Pet id: 2, name: "Spook", person_id: 1>,
       #   #       #<Pet id: 3, name: "Choo-Choo", person_id: 1>
       #   #    ]
-      def length
-        @association.length
-      end
 
       # Returns +true+ if the collection is empty. If the collection has been
       # loaded it is equivalent
       # to <tt>collection.size.zero?</tt>. If the collection has not been loaded,
-      # it is equivalent to <tt>collection.exists?</tt>. If the collection has
+      # it is equivalent to <tt>!collection.exists?</tt>. If the collection has
       # not already been loaded and you are going to fetch the records anyway it
       # is better to check <tt>collection.length.zero?</tt>.
       #
@@ -812,6 +860,12 @@ module ActiveRecord
         @association.empty?
       end
 
+      ##
+      # :method: any?
+      #
+      # :call-seq:
+      #   any?()
+      #
       # Returns +true+ if the collection is not empty.
       #
       #   class Person < ActiveRecord::Base
@@ -841,10 +895,13 @@ module ActiveRecord
       #     pet.group == 'dogs'
       #   end
       #   # => true
-      def any?(&block)
-        @association.any?(&block)
-      end
 
+      ##
+      # :method: many?
+      #
+      # :call-seq:
+      #   many?()
+      #
       # Returns true if the collection has more than one record.
       # Equivalent to <tt>collection.size > 1</tt>.
       #
@@ -879,9 +936,6 @@ module ActiveRecord
       #     pet.group == 'cats'
       #   end
       #   # => true
-      def many?(&block)
-        @association.many?(&block)
-      end
 
       # Returns +true+ if the given +record+ is present in the collection.
       #
@@ -897,27 +951,14 @@ module ActiveRecord
         !!@association.include?(record)
       end
 
-      def arel #:nodoc:
-        scope.arel
-      end
-
       def proxy_association
         @association
       end
 
-      # We don't want this object to be put on the scoping stack, because
-      # that could create an infinite loop where we call an @association
-      # method, which gets the current scope, which is this object, which
-      # delegates to @association, and so on.
-      def scoping
-        @association.scope.scoping { yield }
-      end
-
       # Returns a <tt>Relation</tt> object for the records in this association
       def scope
-        @association.scope
+        @scope ||= @association.scope
       end
-      alias spawn scope
 
       # Equivalent to <tt>Array#==</tt>. Returns +true+ if the two arrays
       # contain the same number of elements and if each element is equal
@@ -947,6 +988,12 @@ module ActiveRecord
         load_target == other
       end
 
+      ##
+      # :method: to_ary
+      #
+      # :call-seq:
+      #   to_ary()
+      #
       # Returns a new array of objects from the collection. If the collection
       # hasn't been loaded, it fetches the records from the database.
       #
@@ -980,10 +1027,6 @@ module ActiveRecord
       #   #       #<Pet id: 5, name: "Brain", person_id: 1>,
       #   #       #<Pet id: 6, name: "Boss",  person_id: 1>
       #   #    ]
-      def to_ary
-        load_target.dup
-      end
-      alias_method :to_a, :to_ary
 
       def records # :nodoc:
         load_target
@@ -1031,7 +1074,6 @@ module ActiveRecord
       end
 
       # Reloads the collection from the database. Returns +self+.
-      # Equivalent to <tt>collection(true)</tt>.
       #
       #   class Person < ActiveRecord::Base
       #     has_many :pets
@@ -1045,12 +1087,9 @@ module ActiveRecord
       #
       #   person.pets.reload # fetches pets from the database
       #   # => [#<Pet id: 1, name: "Snoop", group: "dogs", person_id: 1>]
-      #
-      #   person.pets(true)  # fetches pets from the database
-      #   # => [#<Pet id: 1, name: "Snoop", group: "dogs", person_id: 1>]
       def reload
         proxy_association.reload
-        self
+        reset_scope
       end
 
       # Unloads the association. Returns +self+.
@@ -1072,8 +1111,47 @@ module ActiveRecord
       def reset
         proxy_association.reset
         proxy_association.reset_scope
+        reset_scope
+      end
+
+      def reset_scope # :nodoc:
+        @offsets = {}
+        @scope = nil
         self
       end
+
+      delegate_methods = [
+        QueryMethods,
+        SpawnMethods,
+      ].flat_map { |klass|
+        klass.public_instance_methods(false)
+      } - self.public_instance_methods(false) - [:select] + [:scoping]
+
+      delegate(*delegate_methods, to: :scope)
+
+      private
+
+        def find_nth_with_limit(index, limit)
+          load_target if find_from_target?
+          super
+        end
+
+        def find_nth_from_last(index)
+          load_target if find_from_target?
+          super
+        end
+
+        def null_scope?
+          @association.null_scope?
+        end
+
+        def find_from_target?
+          @association.find_from_target?
+        end
+
+        def exec_queries
+          load_target
+        end
     end
   end
 end
diff --git a/activerecord/lib/active_record/associations/foreign_association.rb b/activerecord/lib/active_record/associations/foreign_association.rb
index 3ceec0ee46..40010cde03 100644
--- a/activerecord/lib/active_record/associations/foreign_association.rb
+++ b/activerecord/lib/active_record/associations/foreign_association.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActiveRecord::Associations
   module ForeignAssociation # :nodoc:
     def foreign_key_present?
diff --git a/activerecord/lib/active_record/associations/has_many_association.rb b/activerecord/lib/active_record/associations/has_many_association.rb
index a9f6aaafef..cf85a87fa7 100644
--- a/activerecord/lib/active_record/associations/has_many_association.rb
+++ b/activerecord/lib/active_record/associations/has_many_association.rb
@@ -1,6 +1,8 @@
+# frozen_string_literal: true
+
 module ActiveRecord
-  # = Active Record Has Many Association
   module Associations
+    # = Active Record Has Many Association
     # This is the proxy that handles a has many association.
     #
     # If the association has a <tt>:through</tt> option further specialization
@@ -16,37 +18,22 @@ module ActiveRecord
         when :restrict_with_error
           unless empty?
             record = owner.class.human_attribute_name(reflection.name).downcase
-            message = owner.errors.generate_message(:base, :'restrict_dependent_destroy.many', record: record, raise: true) rescue nil
-            if message
-              ActiveSupport::Deprecation.warn(<<-MESSAGE.squish)
-                The error key `:'restrict_dependent_destroy.many'` has been deprecated and will be removed in Rails 5.1.
-                Please use `:'restrict_dependent_destroy.has_many'` instead.
-              MESSAGE
-            end
-            owner.errors.add(:base, message || :'restrict_dependent_destroy.has_many', record: record)
+            owner.errors.add(:base, :'restrict_dependent_destroy.has_many', record: record)
             throw(:abort)
           end
 
+        when :destroy
+          # No point in executing the counter update since we're going to destroy the parent anyway
+          load_target.each { |t| t.destroyed_by_association = reflection }
+          destroy_all
         else
-          if options[:dependent] == :destroy
-            # No point in executing the counter update since we're going to destroy the parent anyway
-            load_target.each { |t| t.destroyed_by_association = reflection }
-            destroy_all
-          else
-            delete_all
-          end
+          delete_all
         end
       end
 
       def insert_record(record, validate = true, raise = false)
         set_owner_attributes(record)
-        set_inverse_instance(record)
-
-        if raise
-          record.save!(:validate => validate)
-        else
-          record.save(:validate => validate)
-        end
+        super
       end
 
       def empty?
@@ -74,15 +61,15 @@ module ActiveRecord
         # the loaded flag is set to true as well.
         def count_records
           count = if reflection.has_cached_counter?
-            owner._read_attribute reflection.counter_cache_column
+            owner._read_attribute(reflection.counter_cache_column).to_i
           else
-            scope.count
+            scope.count(:all)
           end
 
           # If there's nothing in the database and @target has no new records
           # we are certain the current target is an empty array. This is a
           # documented side-effect of the method that may avoid an extra SELECT.
-          @target ||= [] and loaded! if count == 0
+          (@target ||= []) && loaded! if count == 0
 
           [association_scope.limit_value, count].compact.min
         end
@@ -110,7 +97,7 @@ module ActiveRecord
         end
 
         def delete_or_nullify_all_records(method)
-          count = delete_count(method, self.scope)
+          count = delete_count(method, scope)
           update_counter(-count)
         end
 
diff --git a/activerecord/lib/active_record/associations/has_many_through_association.rb b/activerecord/lib/active_record/associations/has_many_through_association.rb
index 36fc381343..adbf52b87c 100644
--- a/activerecord/lib/active_record/associations/has_many_through_association.rb
+++ b/activerecord/lib/active_record/associations/has_many_through_association.rb
@@ -1,6 +1,8 @@
+# frozen_string_literal: true
+
 module ActiveRecord
-  # = Active Record Has Many Through Association
   module Associations
+    # = Active Record Has Many Through Association
     class HasManyThroughAssociation < HasManyAssociation #:nodoc:
       include ThroughAssociation
 
@@ -38,10 +40,8 @@ module ActiveRecord
       def insert_record(record, validate = true, raise = false)
         ensure_not_nested
 
-        if raise
-          record.save!(:validate => validate)
-        else
-          return unless record.save(:validate => validate)
+        if record.new_record? || record.has_changes_to_save?
+          return unless super
         end
 
         save_through_record(record)
@@ -86,7 +86,10 @@ module ActiveRecord
         end
 
         def save_through_record(record)
-          build_through_record(record).save!
+          association = build_through_record(record)
+          if association.changed?
+            association.save!
+          end
         ensure
           @through_records.delete(record.object_id)
         end
@@ -108,6 +111,11 @@ module ActiveRecord
           record
         end
 
+        def remove_records(existing_records, records, method)
+          super
+          delete_through_records(records)
+        end
+
         def target_reflection_has_associated_record?
           !(through_reflection.belongs_to? && owner[through_reflection.foreign_key].blank?)
         end
@@ -146,7 +154,7 @@ module ActiveRecord
               stmt.from scope.klass.arel_table
               stmt.wheres = arel.constraints
 
-              count = scope.klass.connection.delete(stmt, 'SQL', scope.bound_attributes)
+              count = scope.klass.connection.delete(stmt, "SQL")
             end
           when :nullify
             count = scope.update_all(source_reflection.foreign_key => nil)
@@ -196,7 +204,7 @@ module ActiveRecord
 
         def find_target
           return [] unless target_reflection_has_associated_record?
-          get_records
+          super
         end
 
         # NOTE - not sure that we can actually cope with inverses here
diff --git a/activerecord/lib/active_record/associations/has_one_association.rb b/activerecord/lib/active_record/associations/has_one_association.rb
index 0fe9b2e81b..7953b89f61 100644
--- a/activerecord/lib/active_record/associations/has_one_association.rb
+++ b/activerecord/lib/active_record/associations/has_one_association.rb
@@ -1,6 +1,8 @@
+# frozen_string_literal: true
+
 module ActiveRecord
-  # = Active Record Has One Association
   module Associations
+    # = Active Record Has One Association
     class HasOneAssociation < SingularAssociation #:nodoc:
       include ForeignAssociation
 
@@ -12,14 +14,7 @@ module ActiveRecord
         when :restrict_with_error
           if load_target
             record = owner.class.human_attribute_name(reflection.name).downcase
-            message = owner.errors.generate_message(:base, :'restrict_dependent_destroy.one', record: record, raise: true) rescue nil
-            if message
-              ActiveSupport::Deprecation.warn(<<-MESSAGE.squish)
-                The error key `:'restrict_dependent_destroy.one'` has been deprecated and will be removed in Rails 5.1.
-                Please use `:'restrict_dependent_destroy.has_one'` instead.
-              MESSAGE
-            end
-            owner.errors.add(:base, message || :'restrict_dependent_destroy.has_one', record: record)
+            owner.errors.add(:base, :'restrict_dependent_destroy.has_one', record: record)
             throw(:abort)
           end
 
@@ -32,10 +27,10 @@ module ActiveRecord
         raise_on_type_mismatch!(record) if record
         load_target
 
-        return self.target if !(target || record)
+        return target unless target || record
 
         assigning_another_record = target != record
-        if assigning_another_record || record.changed?
+        if assigning_another_record || record.has_changes_to_save?
           save &&= owner.persisted?
 
           transaction_if(save) do
@@ -60,12 +55,13 @@ module ActiveRecord
       def delete(method = options[:dependent])
         if load_target
           case method
-            when :delete
-              target.delete
-            when :destroy
-              target.destroy
-            when :nullify
-              target.update_columns(reflection.foreign_key => nil) if target.persisted?
+          when :delete
+            target.delete
+          when :destroy
+            target.destroyed_by_association = reflection
+            target.destroy
+          when :nullify
+            target.update_columns(reflection.foreign_key => nil) if target.persisted?
           end
         end
       end
@@ -82,18 +78,20 @@ module ActiveRecord
 
         def remove_target!(method)
           case method
-            when :delete
-              target.delete
-            when :destroy
-              target.destroy
-            else
-              nullify_owner_attributes(target)
-
-              if target.persisted? && owner.persisted? && !target.save
-                set_owner_attributes(target)
-                raise RecordNotSaved, "Failed to remove the existing associated #{reflection.name}. " +
-                                      "The record failed to save after its foreign key was set to nil."
-              end
+          when :delete
+            target.delete
+          when :destroy
+            target.destroyed_by_association = reflection
+            target.destroy
+          else
+            nullify_owner_attributes(target)
+            remove_inverse_instance(target)
+
+            if target.persisted? && owner.persisted? && !target.save
+              set_owner_attributes(target)
+              raise RecordNotSaved, "Failed to remove the existing associated #{reflection.name}. " \
+                                    "The record failed to save after its foreign key was set to nil."
+            end
           end
         end
 
diff --git a/activerecord/lib/active_record/associations/has_one_through_association.rb b/activerecord/lib/active_record/associations/has_one_through_association.rb
index 08e0ec691f..36746f9115 100644
--- a/activerecord/lib/active_record/associations/has_one_through_association.rb
+++ b/activerecord/lib/active_record/associations/has_one_through_association.rb
@@ -1,6 +1,8 @@
+# frozen_string_literal: true
+
 module ActiveRecord
-  # = Active Record Has One Through Association
   module Associations
+    # = Active Record Has One Through Association
     class HasOneThroughAssociation < HasOneAssociation #:nodoc:
       include ThroughAssociation
 
@@ -15,13 +17,17 @@ module ActiveRecord
           ensure_not_nested
 
           through_proxy  = owner.association(through_reflection.name)
-          through_record = through_proxy.send(:load_target)
+          through_record = through_proxy.load_target
 
           if through_record && !record
             through_record.destroy
           elsif record
             attributes = construct_join_attributes(record)
 
+            if through_record && through_record.destroyed?
+              through_record = through_proxy.tap(&:reload).target
+            end
+
             if through_record
               through_record.update(attributes)
             elsif owner.new_record?
diff --git a/activerecord/lib/active_record/associations/join_dependency.rb b/activerecord/lib/active_record/associations/join_dependency.rb
index 491152bbcb..df4bf07999 100644
--- a/activerecord/lib/active_record/associations/join_dependency.rb
+++ b/activerecord/lib/active_record/associations/join_dependency.rb
@@ -1,18 +1,20 @@
+# frozen_string_literal: true
+
 module ActiveRecord
   module Associations
     class JoinDependency # :nodoc:
-      autoload :JoinBase,        'active_record/associations/join_dependency/join_base'
-      autoload :JoinAssociation, 'active_record/associations/join_dependency/join_association'
+      autoload :JoinBase,        "active_record/associations/join_dependency/join_base"
+      autoload :JoinAssociation, "active_record/associations/join_dependency/join_association"
 
       class Aliases # :nodoc:
         def initialize(tables)
           @tables = tables
-          @alias_cache = tables.each_with_object({}) { |table,h|
-            h[table.node] = table.columns.each_with_object({}) { |column,i|
+          @alias_cache = tables.each_with_object({}) { |table, h|
+            h[table.node] = table.columns.each_with_object({}) { |column, i|
               i[column.name] = column.alias
             }
           }
-          @name_and_alias_cache = tables.each_with_object({}) { |table,h|
+          @name_and_alias_cache = tables.each_with_object({}) { |table, h|
             h[table.node] = table.columns.map { |column|
               [column.name, column.alias]
             }
@@ -32,21 +34,15 @@ module ActiveRecord
           @alias_cache[node][column]
         end
 
-        class Table < Struct.new(:node, :columns) # :nodoc:
-          def table
-            Arel::Nodes::TableAlias.new node.table, node.aliased_table_name
-          end
-
+        Table = Struct.new(:node, :columns) do # :nodoc:
           def column_aliases
-            t = table
+            t = node.table
             columns.map { |column| t[column.name].as Arel.sql column.alias }
           end
         end
         Column = Struct.new(:name, :alias)
       end
 
-      attr_reader :alias_tracker, :base_klass, :join_root
-
       def self.make_tree(associations)
         hash = {}
         walk_tree associations, hash
@@ -62,7 +58,7 @@ module ActiveRecord
             walk_tree assoc, hash
           end
         when Hash
-          associations.each do |k,v|
+          associations.each do |k, v|
             cache = hash[k] ||= {}
             walk_tree v, cache
           end
@@ -92,11 +88,11 @@ module ActiveRecord
       #    associations # => [:appointments]
       #    joins # =>  []
       #
-      def initialize(base, associations, joins, eager_loading: true)
-        @alias_tracker = AliasTracker.create_with_joins(base.connection, base.table_name, joins, base.type_caster)
+      def initialize(base, table, associations, alias_tracker, eager_loading: true)
+        @alias_tracker = alias_tracker
         @eager_loading = eager_loading
         tree = self.class.make_tree associations
-        @join_root = JoinBase.new base, build(tree, base)
+        @join_root = JoinBase.new(base, table, build(tree, base))
         @join_root.children.each { |child| construct_tables! @join_root, child }
       end
 
@@ -104,37 +100,32 @@ module ActiveRecord
         join_root.drop(1).map!(&:reflection)
       end
 
-      def join_constraints(outer_joins, join_type)
+      def join_constraints(joins_to_add, join_type)
         joins = join_root.children.flat_map { |child|
-
-          if join_type == Arel::Nodes::OuterJoin
-            make_left_outer_joins join_root, child
-          else
-            make_inner_joins join_root, child
-          end
+          make_join_constraints(join_root, child, join_type)
         }
 
-        joins.concat outer_joins.flat_map { |oj|
+        joins.concat joins_to_add.flat_map { |oj|
           if join_root.match? oj.join_root
             walk join_root, oj.join_root
           else
             oj.join_root.children.flat_map { |child|
-              make_outer_joins oj.join_root, child
+              make_join_constraints(oj.join_root, child, join_type)
             }
           end
         }
       end
 
       def aliases
-        Aliases.new join_root.each_with_index.map { |join_part,i|
-          columns = join_part.column_names.each_with_index.map { |column_name,j|
+        @aliases ||= Aliases.new join_root.each_with_index.map { |join_part, i|
+          columns = join_part.column_names.each_with_index.map { |column_name, j|
             Aliases::Column.new column_name, "t#{i}_r#{j}"
           }
           Aliases::Table.new(join_part, columns)
         }
       end
 
-      def instantiate(result_set, aliases)
+      def instantiate(result_set, &block)
         primary_key = aliases.column_alias(join_root, join_root.primary_key)
 
         seen = Hash.new { |i, object_id|
@@ -143,7 +134,7 @@ module ActiveRecord
           }
         }
 
-        model_cache = Hash.new { |h,klass| h[klass] = {} }
+        model_cache = Hash.new { |h, klass| h[klass] = {} }
         parents = model_cache[join_root]
         column_aliases = aliases.column_aliases join_root
 
@@ -154,10 +145,10 @@ module ActiveRecord
           class_name: join_root.base_klass.name
         }
 
-        message_bus.instrument('instantiation.active_record', payload) do
+        message_bus.instrument("instantiation.active_record", payload) do
           result_set.each { |row_hash|
             parent_key = primary_key ? row_hash[primary_key] : row_hash
-            parent = parents[parent_key] ||= join_root.instantiate(row_hash, column_aliases)
+            parent = parents[parent_key] ||= join_root.instantiate(row_hash, column_aliases, &block)
             construct(parent, join_root, row_hash, result_set, seen, model_cache, aliases)
           }
         end
@@ -165,136 +156,134 @@ module ActiveRecord
         parents.values
       end
 
-      private
+      protected
+        attr_reader :alias_tracker, :base_klass, :join_root
 
-      def make_constraints(parent, child, tables, join_type)
-        chain         = child.reflection.chain
-        foreign_table = parent.table
-        foreign_klass = parent.base_klass
-        child.join_constraints(foreign_table, foreign_klass, child, join_type, tables, child.reflection.scope_chain, chain)
-      end
+      private
 
-      def make_outer_joins(parent, child)
-        tables    = table_aliases_for(parent, child)
-        join_type = Arel::Nodes::OuterJoin
-        info      = make_constraints parent, child, tables, join_type
+        def make_constraints(parent, child, tables, join_type)
+          chain         = child.reflection.chain
+          foreign_table = parent.table
+          foreign_klass = parent.base_klass
+          child.join_constraints(foreign_table, foreign_klass, join_type, tables, chain)
+        end
 
-        [info] + child.children.flat_map { |c| make_outer_joins(child, c) }
-      end
+        def make_outer_joins(parent, child)
+          join_type = Arel::Nodes::OuterJoin
+          make_join_constraints(parent, child, join_type, true)
+        end
 
-      def make_left_outer_joins(parent, child)
-        tables    = child.tables
-        join_type = Arel::Nodes::OuterJoin
-        info      = make_constraints parent, child, tables, join_type
+        def make_join_constraints(parent, child, join_type, aliasing = false)
+          tables = aliasing ? table_aliases_for(parent, child) : child.tables
+          joins  = make_constraints(parent, child, tables, join_type)
 
-        [info] + child.children.flat_map { |c| make_left_outer_joins(child, c) }
-      end
+          joins.concat child.children.flat_map { |c| make_join_constraints(child, c, join_type, aliasing) }
+        end
 
-      def make_inner_joins(parent, child)
-        tables    = child.tables
-        join_type = Arel::Nodes::InnerJoin
-        info      = make_constraints parent, child, tables, join_type
+        def table_aliases_for(parent, node)
+          node.reflection.chain.map { |reflection|
+            alias_tracker.aliased_table_for(
+              reflection.table_name,
+              table_alias_for(reflection, parent, reflection != node.reflection),
+              reflection.klass.type_caster
+            )
+          }
+        end
 
-        [info] + child.children.flat_map { |c| make_inner_joins(child, c) }
-      end
+        def construct_tables!(parent, node)
+          node.tables = table_aliases_for(parent, node)
+          node.children.each { |child| construct_tables! node, child }
+        end
 
-      def table_aliases_for(parent, node)
-        node.reflection.chain.map { |reflection|
-          alias_tracker.aliased_table_for(
-            reflection.table_name,
-            table_alias_for(reflection, parent, reflection != node.reflection)
-          )
-        }
-      end
+        def table_alias_for(reflection, parent, join)
+          name = "#{reflection.plural_name}_#{parent.table_name}"
+          join ? "#{name}_join" : name
+        end
 
-      def construct_tables!(parent, node)
-        node.tables = table_aliases_for(parent, node)
-        node.children.each { |child| construct_tables! node, child }
-      end
+        def walk(left, right)
+          intersection, missing = right.children.map { |node1|
+            [left.children.find { |node2| node1.match? node2 }, node1]
+          }.partition(&:first)
 
-      def table_alias_for(reflection, parent, join)
-        name = "#{reflection.plural_name}_#{parent.table_name}"
-        name << "_join" if join
-        name
-      end
+          ojs = missing.flat_map { |_, n| make_outer_joins left, n }
+          intersection.flat_map { |l, r| walk l, r }.concat ojs
+        end
 
-      def walk(left, right)
-        intersection, missing = right.children.map { |node1|
-          [left.children.find { |node2| node1.match? node2 }, node1]
-        }.partition(&:first)
+        def find_reflection(klass, name)
+          klass._reflect_on_association(name) ||
+            raise(ConfigurationError, "Can't join '#{klass.name}' to association named '#{name}'; perhaps you misspelled it?")
+        end
 
-        ojs = missing.flat_map { |_,n| make_outer_joins left, n }
-        intersection.flat_map { |l,r| walk l, r }.concat ojs
-      end
+        def build(associations, base_klass)
+          associations.map do |name, right|
+            reflection = find_reflection base_klass, name
+            reflection.check_validity!
+            reflection.check_eager_loadable!
 
-      def find_reflection(klass, name)
-        klass._reflect_on_association(name) or
-          raise ConfigurationError, "Can't join '#{ klass.name }' to association named '#{ name }'; perhaps you misspelled it?"
-      end
+            if reflection.polymorphic?
+              next unless @eager_loading
+              raise EagerLoadPolymorphicError.new(reflection)
+            end
 
-      def build(associations, base_klass)
-        associations.map do |name, right|
-          reflection = find_reflection base_klass, name
-          reflection.check_validity!
-          reflection.check_eager_loadable!
+            JoinAssociation.new(reflection, build(right, reflection.klass), alias_tracker)
+          end.compact
+        end
 
-          if reflection.polymorphic?
-            next unless @eager_loading
-            raise EagerLoadPolymorphicError.new(reflection)
+        def construct(ar_parent, parent, row, rs, seen, model_cache, aliases)
+          return if ar_parent.nil?
+
+          parent.children.each do |node|
+            if node.reflection.collection?
+              other = ar_parent.association(node.reflection.name)
+              other.loaded!
+            elsif ar_parent.association_cached?(node.reflection.name)
+              model = ar_parent.association(node.reflection.name).target
+              construct(model, node, row, rs, seen, model_cache, aliases)
+              next
+            end
+
+            key = aliases.column_alias(node, node.primary_key)
+            id = row[key]
+            if id.nil?
+              nil_association = ar_parent.association(node.reflection.name)
+              nil_association.loaded!
+              next
+            end
+
+            model = seen[ar_parent.object_id][node.base_klass][id]
+
+            if model
+              construct(model, node, row, rs, seen, model_cache, aliases)
+            else
+              model = construct_model(ar_parent, node, row, model_cache, id, aliases)
+
+              if node.reflection.scope &&
+                  node.reflection.scope_for(node.base_klass.unscoped).readonly_value
+                model.readonly!
+              end
+
+              seen[ar_parent.object_id][node.base_klass][id] = model
+              construct(model, node, row, rs, seen, model_cache, aliases)
+            end
           end
+        end
 
-          JoinAssociation.new reflection, build(right, reflection.klass)
-        end.compact
-      end
+        def construct_model(record, node, row, model_cache, id, aliases)
+          other = record.association(node.reflection.name)
 
-      def construct(ar_parent, parent, row, rs, seen, model_cache, aliases)
-        return if ar_parent.nil?
+          model = model_cache[node][id] ||=
+            node.instantiate(row, aliases.column_aliases(node)) do |m|
+              other.set_inverse_instance(m)
+            end
 
-        parent.children.each do |node|
           if node.reflection.collection?
-            other = ar_parent.association(node.reflection.name)
-            other.loaded!
-          elsif ar_parent.association_cached?(node.reflection.name)
-            model = ar_parent.association(node.reflection.name).target
-            construct(model, node, row, rs, seen, model_cache, aliases)
-            next
-          end
-
-          key = aliases.column_alias(node, node.primary_key)
-          id = row[key]
-          if id.nil?
-            nil_association = ar_parent.association(node.reflection.name)
-            nil_association.loaded!
-            next
-          end
-
-          model = seen[ar_parent.object_id][node.base_klass][id]
-
-          if model
-            construct(model, node, row, rs, seen, model_cache, aliases)
+            other.target.push(model)
           else
-            model = construct_model(ar_parent, node, row, model_cache, id, aliases)
-            model.readonly!
-            seen[ar_parent.object_id][node.base_klass][id] = model
-            construct(model, node, row, rs, seen, model_cache, aliases)
+            other.target = model
           end
-        end
-      end
-
-      def construct_model(record, node, row, model_cache, id, aliases)
-        model = model_cache[node][id] ||= node.instantiate(row,
-                                                           aliases.column_aliases(node))
-        other = record.association(node.reflection.name)
 
-        if node.reflection.collection?
-          other.target.push(model)
-        else
-          other.target = model
+          model
         end
-
-        other.set_inverse_instance(model)
-        model
-      end
     end
   end
 end
diff --git a/activerecord/lib/active_record/associations/join_dependency/join_association.rb b/activerecord/lib/active_record/associations/join_dependency/join_association.rb
index c5fbe0d1d1..221c791bf8 100644
--- a/activerecord/lib/active_record/associations/join_dependency/join_association.rb
+++ b/activerecord/lib/active_record/associations/join_dependency/join_association.rb
@@ -1,4 +1,6 @@
-require 'active_record/associations/join_dependency/join_part'
+# frozen_string_literal: true
+
+require "active_record/associations/join_dependency/join_part"
 
 module ActiveRecord
   module Associations
@@ -9,11 +11,12 @@ module ActiveRecord
 
         attr_accessor :tables
 
-        def initialize(reflection, children)
+        def initialize(reflection, children, alias_tracker)
           super(reflection.klass, children)
 
-          @reflection      = reflection
-          @tables          = nil
+          @alias_tracker = alias_tracker
+          @reflection    = reflection
+          @tables        = nil
         end
 
         def match?(other)
@@ -21,113 +24,42 @@ module ActiveRecord
           super && reflection == other.reflection
         end
 
-        JoinInformation = Struct.new :joins, :binds
-
-        def join_constraints(foreign_table, foreign_klass, node, join_type, tables, scope_chain, chain)
+        def join_constraints(foreign_table, foreign_klass, join_type, tables, chain)
           joins         = []
-          binds         = []
           tables        = tables.reverse
 
-          scope_chain_index = 0
-          scope_chain = scope_chain.reverse
-
           # The chain starts with the target table, but we want to end with it here (makes
           # more sense in this context), so we reverse
           chain.reverse_each do |reflection|
             table = tables.shift
             klass = reflection.klass
 
-            join_keys   = reflection.join_keys(klass)
-            key         = join_keys.key
-            foreign_key = join_keys.foreign_key
-
-            constraint = build_constraint(klass, table, key, foreign_table, foreign_key)
+            constraint = reflection.build_join_constraint(table, foreign_table)
 
-            predicate_builder = PredicateBuilder.new(TableMetadata.new(klass, table))
-            scope_chain_items = scope_chain[scope_chain_index].map do |item|
-              if item.is_a?(Relation)
-                item
-              else
-                ActiveRecord::Relation.create(klass, table, predicate_builder)
-                  .instance_exec(node, &item)
-              end
-            end
-            scope_chain_index += 1
-
-            klass_scope =
-              if klass.current_scope
-                klass.current_scope.clone
-              else
-                relation = ActiveRecord::Relation.create(
-                  klass,
-                  table,
-                  predicate_builder,
-                )
-                klass.send(:build_default_scope, relation)
-              end
-            scope_chain_items.concat [klass_scope].compact
-
-            rel = scope_chain_items.inject(scope_chain_items.shift) do |left, right|
-              left.merge right
-            end
-
-            if rel && !rel.arel.constraints.empty?
-              binds += rel.bound_attributes
-              constraint = constraint.and rel.arel.constraints
-            end
+            joins << table.create_join(table, table.create_on(constraint), join_type)
 
-            if reflection.type
-              value = foreign_klass.base_class.name
-              column = klass.columns_hash[reflection.type.to_s]
+            join_scope = reflection.join_scope(table, foreign_klass)
+            arel = join_scope.arel(alias_tracker.aliases)
 
-              binds << Relation::QueryAttribute.new(column.name, value, klass.type_for_attribute(column.name))
-              constraint = constraint.and klass.arel_attribute(reflection.type, table).eq(Arel::Nodes::BindParam.new)
+            if arel.constraints.any?
+              joins.concat arel.join_sources
+              right = joins.last.right
+              right.expr = right.expr.and(arel.constraints)
             end
 
-            joins << table.create_join(table, table.create_on(constraint), join_type)
-
             # The current table in this iteration becomes the foreign table in the next
             foreign_table, foreign_klass = table, klass
           end
 
-          JoinInformation.new joins, binds
-        end
-
-        #  Builds equality condition.
-        #
-        #  Example:
-        #
-        #  class Physician < ActiveRecord::Base
-        #    has_many :appointments
-        #  end
-        #
-        #  If I execute `Physician.joins(:appointments).to_a` then
-        #    klass         # => Physician
-        #    table         # => #<Arel::Table @name="appointments" ...>
-        #    key           # =>  physician_id
-        #    foreign_table # => #<Arel::Table @name="physicians" ...>
-        #    foreign_key   # => id
-        #
-        def build_constraint(klass, table, key, foreign_table, foreign_key)
-          constraint = table[key].eq(foreign_table[foreign_key])
-
-          if klass.finder_needs_type_condition?
-            constraint = table.create_and([
-              constraint,
-              klass.send(:type_condition, table)
-            ])
-          end
-
-          constraint
+          joins
         end
 
         def table
           tables.first
         end
 
-        def aliased_table_name
-          table.table_alias || table.name
-        end
+        protected
+          attr_reader :alias_tracker
       end
     end
   end
diff --git a/activerecord/lib/active_record/associations/join_dependency/join_base.rb b/activerecord/lib/active_record/associations/join_dependency/join_base.rb
index 3a26c25737..988b4e8fa2 100644
--- a/activerecord/lib/active_record/associations/join_dependency/join_base.rb
+++ b/activerecord/lib/active_record/associations/join_dependency/join_base.rb
@@ -1,20 +1,21 @@
-require 'active_record/associations/join_dependency/join_part'
+# frozen_string_literal: true
+
+require "active_record/associations/join_dependency/join_part"
 
 module ActiveRecord
   module Associations
     class JoinDependency # :nodoc:
       class JoinBase < JoinPart # :nodoc:
-        def match?(other)
-          return true if self == other
-          super && base_klass == other.base_klass
-        end
+        attr_reader :table
 
-        def table
-          base_klass.arel_table
+        def initialize(base_klass, table, children)
+          super(base_klass, children)
+          @table = table
         end
 
-        def aliased_table_name
-          base_klass.table_name
+        def match?(other)
+          return true if self == other
+          super && base_klass == other.base_klass
         end
       end
     end
diff --git a/activerecord/lib/active_record/associations/join_dependency/join_part.rb b/activerecord/lib/active_record/associations/join_dependency/join_part.rb
index 9c6573f913..2181f308bf 100644
--- a/activerecord/lib/active_record/associations/join_dependency/join_part.rb
+++ b/activerecord/lib/active_record/associations/join_dependency/join_part.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActiveRecord
   module Associations
     class JoinDependency # :nodoc:
@@ -15,17 +17,13 @@ module ActiveRecord
         # association.
         attr_reader :base_klass, :children
 
-        delegate :table_name, :column_names, :primary_key, :to => :base_klass
+        delegate :table_name, :column_names, :primary_key, to: :base_klass
 
         def initialize(base_klass, children)
           @base_klass = base_klass
           @children = children
         end
 
-        def name
-          reflection.name
-        end
-
         def match?(other)
           self.class == other.class
         end
@@ -40,11 +38,6 @@ module ActiveRecord
           raise NotImplementedError
         end
 
-        # The alias for the active_record's table
-        def aliased_table_name
-          raise NotImplementedError
-        end
-
         def extract_record(row, column_names_with_alias)
           # This code is performance critical as it is called per row.
           # see: https://github.com/rails/rails/pull/12185
@@ -62,8 +55,8 @@ module ActiveRecord
           hash
         end
 
-        def instantiate(row, aliases)
-          base_klass.instantiate(extract_record(row, aliases))
+        def instantiate(row, aliases, &block)
+          base_klass.instantiate(extract_record(row, aliases), &block)
         end
       end
     end
diff --git a/activerecord/lib/active_record/associations/preloader.rb b/activerecord/lib/active_record/associations/preloader.rb
index e64af84e1a..e1087be9b3 100644
--- a/activerecord/lib/active_record/associations/preloader.rb
+++ b/activerecord/lib/active_record/associations/preloader.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActiveRecord
   module Associations
     # Implements the details of eager loading of Active Record associations.
@@ -42,20 +44,10 @@ module ActiveRecord
       extend ActiveSupport::Autoload
 
       eager_autoload do
-        autoload :Association,           'active_record/associations/preloader/association'
-        autoload :SingularAssociation,   'active_record/associations/preloader/singular_association'
-        autoload :CollectionAssociation, 'active_record/associations/preloader/collection_association'
-        autoload :ThroughAssociation,    'active_record/associations/preloader/through_association'
-
-        autoload :HasMany,             'active_record/associations/preloader/has_many'
-        autoload :HasManyThrough,      'active_record/associations/preloader/has_many_through'
-        autoload :HasOne,              'active_record/associations/preloader/has_one'
-        autoload :HasOneThrough,       'active_record/associations/preloader/has_one_through'
-        autoload :BelongsTo,           'active_record/associations/preloader/belongs_to'
+        autoload :Association,        "active_record/associations/preloader/association"
+        autoload :ThroughAssociation, "active_record/associations/preloader/through_association"
       end
 
-      NULL_RELATION = Struct.new(:values, :where_clause, :joins_values).new({}, Relation::WhereClause.empty, [])
-
       # Eager loads the named associations for the given Active Record record(s).
       #
       # In this description, 'association name' shall refer to the name passed
@@ -91,14 +83,13 @@ module ActiveRecord
       #   { author: :avatar }
       #   [ :books, { author: :avatar } ]
       def preload(records, associations, preload_scope = nil)
-        records       = Array.wrap(records).compact.uniq
-        associations  = Array.wrap(associations)
-        preload_scope = preload_scope || NULL_RELATION
+        records = records.compact
 
         if records.empty?
           []
         else
-          associations.flat_map { |association|
+          records.uniq!
+          Array.wrap(associations).flat_map { |association|
             preloaders_on association, records, preload_scope
           }
         end
@@ -106,108 +97,97 @@ module ActiveRecord
 
       private
 
-      # Loads all the given data into +records+ for the +association+.
-      def preloaders_on(association, records, scope)
-        case association
-        when Hash
-          preloaders_for_hash(association, records, scope)
-        when Symbol
-          preloaders_for_one(association, records, scope)
-        when String
-          preloaders_for_one(association.to_sym, records, scope)
-        else
-          raise ArgumentError, "#{association.inspect} was not recognized for preload"
+        # Loads all the given data into +records+ for the +association+.
+        def preloaders_on(association, records, scope)
+          case association
+          when Hash
+            preloaders_for_hash(association, records, scope)
+          when Symbol
+            preloaders_for_one(association, records, scope)
+          when String
+            preloaders_for_one(association.to_sym, records, scope)
+          else
+            raise ArgumentError, "#{association.inspect} was not recognized for preload"
+          end
         end
-      end
 
-      def preloaders_for_hash(association, records, scope)
-        association.flat_map { |parent, child|
-          loaders = preloaders_for_one parent, records, scope
+        def preloaders_for_hash(association, records, scope)
+          association.flat_map { |parent, child|
+            loaders = preloaders_for_one parent, records, scope
 
-          recs = loaders.flat_map(&:preloaded_records).uniq
-          loaders.concat Array.wrap(child).flat_map { |assoc|
-            preloaders_on assoc, recs, scope
+            recs = loaders.flat_map(&:preloaded_records).uniq
+            loaders.concat Array.wrap(child).flat_map { |assoc|
+              preloaders_on assoc, recs, scope
+            }
+            loaders
           }
-          loaders
-        }
-      end
+        end
 
-      # Loads all the given data into +records+ for a singular +association+.
-      #
-      # Functions by instantiating a preloader class such as Preloader::HasManyThrough and
-      # call the +run+ method for each passed in class in the +records+ argument.
-      #
-      # Not all records have the same class, so group then preload group on the reflection
-      # itself so that if various subclass share the same association then we do not split
-      # them unnecessarily
-      #
-      # Additionally, polymorphic belongs_to associations can have multiple associated
-      # classes, depending on the polymorphic_type field. So we group by the classes as
-      # well.
-      def preloaders_for_one(association, records, scope)
-        grouped_records(association, records).flat_map do |reflection, klasses|
-          klasses.map do |rhs_klass, rs|
-            loader = preloader_for(reflection, rs, rhs_klass).new(rhs_klass, rs, reflection, scope)
-            loader.run self
-            loader
+        # Loads all the given data into +records+ for a singular +association+.
+        #
+        # Functions by instantiating a preloader class such as Preloader::HasManyThrough and
+        # call the +run+ method for each passed in class in the +records+ argument.
+        #
+        # Not all records have the same class, so group then preload group on the reflection
+        # itself so that if various subclass share the same association then we do not split
+        # them unnecessarily
+        #
+        # Additionally, polymorphic belongs_to associations can have multiple associated
+        # classes, depending on the polymorphic_type field. So we group by the classes as
+        # well.
+        def preloaders_for_one(association, records, scope)
+          grouped_records(association, records).flat_map do |reflection, klasses|
+            klasses.map do |rhs_klass, rs|
+              loader = preloader_for(reflection, rs).new(rhs_klass, rs, reflection, scope)
+              loader.run self
+              loader
+            end
           end
         end
-      end
 
-      def grouped_records(association, records)
-        h = {}
-        records.each do |record|
-          next unless record
-          assoc = record.association(association)
-          klasses = h[assoc.reflection] ||= {}
-          (klasses[assoc.klass] ||= []) << record
+        def grouped_records(association, records)
+          h = {}
+          records.each do |record|
+            next unless record
+            assoc = record.association(association)
+            next unless assoc.klass
+            klasses = h[assoc.reflection] ||= {}
+            (klasses[assoc.klass] ||= []) << record
+          end
+          h
         end
-        h
-      end
 
-      class AlreadyLoaded # :nodoc:
-        attr_reader :owners, :reflection
+        class AlreadyLoaded # :nodoc:
+          def initialize(klass, owners, reflection, preload_scope)
+            @owners = owners
+            @reflection = reflection
+          end
 
-        def initialize(klass, owners, reflection, preload_scope)
-          @owners = owners
-          @reflection = reflection
-        end
+          def run(preloader); end
 
-        def run(preloader); end
+          def preloaded_records
+            owners.flat_map { |owner| owner.association(reflection.name).target }
+          end
 
-        def preloaded_records
-          owners.flat_map { |owner| owner.association(reflection.name).target }
+          protected
+            attr_reader :owners, :reflection
         end
-      end
 
-      class NullPreloader # :nodoc:
-        def self.new(klass, owners, reflection, preload_scope); self; end
-        def self.run(preloader); end
-        def self.preloaded_records; []; end
-        def self.owners; []; end
-      end
-
-      # Returns a class containing the logic needed to load preload the data
-      # and attach it to a relation. For example +Preloader::Association+ or
-      # +Preloader::HasManyThrough+. The class returned implements a `run` method
-      # that accepts a preloader.
-      def preloader_for(reflection, owners, rhs_klass)
-        return NullPreloader unless rhs_klass
+        # Returns a class containing the logic needed to load preload the data
+        # and attach it to a relation. The class returned implements a `run` method
+        # that accepts a preloader.
+        def preloader_for(reflection, owners)
+          if owners.first.association(reflection.name).loaded?
+            return AlreadyLoaded
+          end
+          reflection.check_preloadable!
 
-        if owners.first.association(reflection.name).loaded?
-          return AlreadyLoaded
-        end
-        reflection.check_preloadable!
-
-        case reflection.macro
-        when :has_many
-          reflection.options[:through] ? HasManyThrough : HasMany
-        when :has_one
-          reflection.options[:through] ? HasOneThrough : HasOne
-        when :belongs_to
-          BelongsTo
+          if reflection.options[:through]
+            ThroughAssociation
+          else
+            Association
+          end
         end
-      end
     end
   end
 end
diff --git a/activerecord/lib/active_record/associations/preloader/association.rb b/activerecord/lib/active_record/associations/preloader/association.rb
index 3032bc786e..735da152b7 100644
--- a/activerecord/lib/active_record/associations/preloader/association.rb
+++ b/activerecord/lib/active_record/associations/preloader/association.rb
@@ -1,8 +1,9 @@
+# frozen_string_literal: true
+
 module ActiveRecord
   module Associations
     class Preloader
       class Association #:nodoc:
-        attr_reader :owners, :reflection, :preload_scope, :model, :klass
         attr_reader :preloaded_records
 
         def initialize(klass, owners, reflection, preload_scope)
@@ -11,149 +12,119 @@ module ActiveRecord
           @reflection    = reflection
           @preload_scope = preload_scope
           @model         = owners.first && owners.first.class
-          @scope         = nil
           @preloaded_records = []
         end
 
         def run(preloader)
-          preload(preloader)
-        end
-
-        def preload(preloader)
-          raise NotImplementedError
-        end
-
-        def scope
-          @scope ||= build_scope
-        end
-
-        def records_for(ids)
-          query_scope(ids)
-        end
-
-        def query_scope(ids)
-          scope.where(association_key_name => ids)
-        end
-
-        def table
-          klass.arel_table
-        end
-
-        # The name of the key on the associated records
-        def association_key_name
-          raise NotImplementedError
-        end
+          records = load_records do |record|
+            owner = owners_by_key[convert_key(record[association_key_name])]
+            association = owner.association(reflection.name)
+            association.set_inverse_instance(record)
+          end
 
-        # This is overridden by HABTM as the condition should be on the foreign_key column in
-        # the join table
-        def association_key
-          klass.arel_attribute(association_key_name, table)
+          owners.each do |owner|
+            associate_records_to_owner(owner, records[convert_key(owner[owner_key_name])] || [])
+          end
         end
 
-        # The name of the key on the model which declares the association
-        def owner_key_name
-          raise NotImplementedError
-        end
-
-        def options
-          reflection.options
-        end
+        protected
+          attr_reader :owners, :reflection, :preload_scope, :model, :klass
 
         private
+          # The name of the key on the associated records
+          def association_key_name
+            reflection.join_primary_key(klass)
+          end
 
-        def associated_records_by_owner(preloader)
-          records = load_records
-          owners.each_with_object({}) do |owner, result|
-            result[owner] = records[convert_key(owner[owner_key_name])] || []
+          # The name of the key on the model which declares the association
+          def owner_key_name
+            reflection.join_foreign_key
           end
-        end
 
-        def owner_keys
-          unless defined?(@owner_keys)
-            @owner_keys = owners.map do |owner|
-              owner[owner_key_name]
+          def associate_records_to_owner(owner, records)
+            association = owner.association(reflection.name)
+            if reflection.collection?
+              association.loaded!
+              association.target.concat(records)
+            else
+              association.target = records.first
             end
-            @owner_keys.uniq!
-            @owner_keys.compact!
           end
-          @owner_keys
-        end
-
-        def key_conversion_required?
-          @key_conversion_required ||= association_key_type != owner_key_type
-        end
 
-        def convert_key(key)
-          if key_conversion_required?
-            key.to_s
-          else
-            key
+          def owner_keys
+            @owner_keys ||= owners_by_key.keys
           end
-        end
-
-        def association_key_type
-          @klass.type_for_attribute(association_key_name.to_s).type
-        end
-
-        def owner_key_type
-          @model.type_for_attribute(owner_key_name.to_s).type
-        end
 
-        def load_records
-          return {} if owner_keys.empty?
-          # Some databases impose a limit on the number of ids in a list (in Oracle it's 1000)
-          # Make several smaller queries if necessary or make one query if the adapter supports it
-          slices  = owner_keys.each_slice(klass.connection.in_clause_length || owner_keys.size)
-          @preloaded_records = slices.flat_map do |slice|
-            records_for(slice)
-          end
-          @preloaded_records.group_by do |record| 
-            convert_key(record[association_key_name])
+          def owners_by_key
+            unless defined?(@owners_by_key)
+              @owners_by_key = owners.each_with_object({}) do |owner, h|
+                key = convert_key(owner[owner_key_name])
+                h[key] = owner if key
+              end
+            end
+            @owners_by_key
           end
-        end
 
-        def reflection_scope
-          @reflection_scope ||= reflection.scope ? klass.unscoped.instance_exec(nil, &reflection.scope) : klass.unscoped
-        end
-
-        def build_scope
-          scope = klass.unscoped
+          def key_conversion_required?
+            unless defined?(@key_conversion_required)
+              @key_conversion_required = (association_key_type != owner_key_type)
+            end
 
-          values = reflection_scope.values
-          preload_values = preload_scope.values
+            @key_conversion_required
+          end
 
-          scope.where_clause = reflection_scope.where_clause + preload_scope.where_clause
-          scope.references_values = Array(values[:references]) + Array(preload_values[:references])
+          def convert_key(key)
+            if key_conversion_required?
+              key.to_s
+            else
+              key
+            end
+          end
 
-          if preload_values[:select] || values[:select]
-            scope._select!(preload_values[:select] || values[:select])
+          def association_key_type
+            @klass.type_for_attribute(association_key_name.to_s).type
           end
-          scope.includes! preload_values[:includes] || values[:includes]
-          if preload_scope.joins_values.any?
-            scope.joins!(preload_scope.joins_values)
-          else
-            scope.joins!(reflection_scope.joins_values)
+
+          def owner_key_type
+            @model.type_for_attribute(owner_key_name.to_s).type
           end
 
-          if order_values = preload_values[:order] || values[:order]
-            scope.order!(order_values)
+          def load_records(&block)
+            return {} if owner_keys.empty?
+            # Some databases impose a limit on the number of ids in a list (in Oracle it's 1000)
+            # Make several smaller queries if necessary or make one query if the adapter supports it
+            slices = owner_keys.each_slice(klass.connection.in_clause_length || owner_keys.size)
+            @preloaded_records = slices.flat_map do |slice|
+              records_for(slice, &block)
+            end
+            @preloaded_records.group_by do |record|
+              convert_key(record[association_key_name])
+            end
           end
 
-          if preload_values[:reordering] || values[:reordering]
-            scope.reordering_value = true
+          def records_for(ids, &block)
+            scope.where(association_key_name => ids).load(&block)
           end
 
-          if preload_values[:readonly] || values[:readonly]
-            scope.readonly!
+          def scope
+            @scope ||= build_scope
           end
 
-          if options[:as]
-            scope.where!(klass.table_name => { reflection.type => model.base_class.sti_name })
+          def reflection_scope
+            @reflection_scope ||= reflection.scope ? reflection.scope_for(klass.unscoped) : klass.unscoped
           end
 
-          scope.unscope_values = Array(values[:unscope]) + Array(preload_values[:unscope])
-          klass.default_scoped.merge(scope)
-        end
+          def build_scope
+            scope = klass.scope_for_association
+
+            if reflection.type
+              scope.where!(reflection.type => model.base_class.sti_name)
+            end
+
+            scope.merge!(reflection_scope) if reflection.scope
+            scope.merge!(preload_scope) if preload_scope
+            scope
+          end
       end
     end
   end
diff --git a/activerecord/lib/active_record/associations/preloader/belongs_to.rb b/activerecord/lib/active_record/associations/preloader/belongs_to.rb
deleted file mode 100644
index 5091d4717a..0000000000
--- a/activerecord/lib/active_record/associations/preloader/belongs_to.rb
+++ /dev/null
@@ -1,17 +0,0 @@
-module ActiveRecord
-  module Associations
-    class Preloader
-      class BelongsTo < SingularAssociation #:nodoc:
-
-        def association_key_name
-          reflection.options[:primary_key] || klass && klass.primary_key
-        end
-
-        def owner_key_name
-          reflection.foreign_key
-        end
-
-      end
-    end
-  end
-end
diff --git a/activerecord/lib/active_record/associations/preloader/collection_association.rb b/activerecord/lib/active_record/associations/preloader/collection_association.rb
deleted file mode 100644
index 9939280fa4..0000000000
--- a/activerecord/lib/active_record/associations/preloader/collection_association.rb
+++ /dev/null
@@ -1,18 +0,0 @@
-module ActiveRecord
-  module Associations
-    class Preloader
-      class CollectionAssociation < Association #:nodoc:
-        private
-
-        def preload(preloader)
-          associated_records_by_owner(preloader).each do |owner, records|
-            association = owner.association(reflection.name)
-            association.loaded!
-            association.target.concat(records)
-            records.each { |record| association.set_inverse_instance(record) }
-          end
-        end
-      end
-    end
-  end
-end
diff --git a/activerecord/lib/active_record/associations/preloader/has_many.rb b/activerecord/lib/active_record/associations/preloader/has_many.rb
deleted file mode 100644
index 3ea91a8c11..0000000000
--- a/activerecord/lib/active_record/associations/preloader/has_many.rb
+++ /dev/null
@@ -1,17 +0,0 @@
-module ActiveRecord
-  module Associations
-    class Preloader
-      class HasMany < CollectionAssociation #:nodoc:
-
-        def association_key_name
-          reflection.foreign_key
-        end
-
-        def owner_key_name
-          reflection.active_record_primary_key
-        end
-
-      end
-    end
-  end
-end
diff --git a/activerecord/lib/active_record/associations/preloader/has_many_through.rb b/activerecord/lib/active_record/associations/preloader/has_many_through.rb
deleted file mode 100644
index 2029871f39..0000000000
--- a/activerecord/lib/active_record/associations/preloader/has_many_through.rb
+++ /dev/null
@@ -1,19 +0,0 @@
-module ActiveRecord
-  module Associations
-    class Preloader
-      class HasManyThrough < CollectionAssociation #:nodoc:
-        include ThroughAssociation
-
-        def associated_records_by_owner(preloader)
-          records_by_owner = super
-
-          if reflection_scope.distinct_value
-            records_by_owner.each_value(&:uniq!)
-          end
-
-          records_by_owner
-        end
-      end
-    end
-  end
-end
diff --git a/activerecord/lib/active_record/associations/preloader/has_one.rb b/activerecord/lib/active_record/associations/preloader/has_one.rb
deleted file mode 100644
index c4add621ca..0000000000
--- a/activerecord/lib/active_record/associations/preloader/has_one.rb
+++ /dev/null
@@ -1,15 +0,0 @@
-module ActiveRecord
-  module Associations
-    class Preloader
-      class HasOne < SingularAssociation #:nodoc:
-        def association_key_name
-          reflection.foreign_key
-        end
-
-        def owner_key_name
-          reflection.active_record_primary_key
-        end
-      end
-    end
-  end
-end
diff --git a/activerecord/lib/active_record/associations/preloader/has_one_through.rb b/activerecord/lib/active_record/associations/preloader/has_one_through.rb
deleted file mode 100644
index f063f85574..0000000000
--- a/activerecord/lib/active_record/associations/preloader/has_one_through.rb
+++ /dev/null
@@ -1,9 +0,0 @@
-module ActiveRecord
-  module Associations
-    class Preloader
-      class HasOneThrough < SingularAssociation #:nodoc:
-        include ThroughAssociation
-      end
-    end
-  end
-end
diff --git a/activerecord/lib/active_record/associations/preloader/singular_association.rb b/activerecord/lib/active_record/associations/preloader/singular_association.rb
deleted file mode 100644
index f60647a81e..0000000000
--- a/activerecord/lib/active_record/associations/preloader/singular_association.rb
+++ /dev/null
@@ -1,21 +0,0 @@
-module ActiveRecord
-  module Associations
-    class Preloader
-      class SingularAssociation < Association #:nodoc:
-
-        private
-
-        def preload(preloader)
-          associated_records_by_owner(preloader).each do |owner, associated_records|
-            record = associated_records.first
-
-            association = owner.association(reflection.name)
-            association.target = record
-            association.set_inverse_instance(record) if record
-          end
-        end
-
-      end
-    end
-  end
-end
diff --git a/activerecord/lib/active_record/associations/preloader/through_association.rb b/activerecord/lib/active_record/associations/preloader/through_association.rb
index b0203909ce..a6b7ab80a2 100644
--- a/activerecord/lib/active_record/associations/preloader/through_association.rb
+++ b/activerecord/lib/active_record/associations/preloader/through_association.rb
@@ -1,108 +1,106 @@
+# frozen_string_literal: true
+
 module ActiveRecord
   module Associations
     class Preloader
-      module ThroughAssociation #:nodoc:
-        def through_reflection
-          reflection.through_reflection
-        end
+      class ThroughAssociation < Association # :nodoc:
+        def run(preloader)
+          already_loaded     = owners.first.association(through_reflection.name).loaded?
+          through_scope      = through_scope()
+          reflection_scope   = target_reflection_scope
+          through_preloaders = preloader.preload(owners, through_reflection.name, through_scope)
+          middle_records     = through_preloaders.flat_map(&:preloaded_records)
+          preloaders         = preloader.preload(middle_records, source_reflection.name, reflection_scope)
+          @preloaded_records = preloaders.flat_map(&:preloaded_records)
 
-        def source_reflection
-          reflection.source_reflection
+          owners.each do |owner|
+            through_records = Array(owner.association(through_reflection.name).target)
+            if already_loaded
+              if source_type = reflection.options[:source_type]
+                through_records = through_records.select do |record|
+                  record[reflection.foreign_type] == source_type
+                end
+              end
+            else
+              owner.association(through_reflection.name).reset if through_scope
+            end
+            result = through_records.flat_map do |record|
+              association = record.association(source_reflection.name)
+              target = association.target
+              association.reset if preload_scope
+              target
+            end
+            result.compact!
+            if reflection_scope
+              result.sort_by! { |rhs| preload_index[rhs] } if reflection_scope.order_values.any?
+              result.uniq! if reflection_scope.distinct_value
+            end
+            associate_records_to_owner(owner, result)
+          end
         end
 
-        def associated_records_by_owner(preloader)
-          preloader.preload(owners,
-                            through_reflection.name,
-                            through_scope)
-
-          through_records = owners.map do |owner|
-            association = owner.association through_reflection.name
-
-            center = target_records_from_association(association)
-            [owner, Array(center)]
+        private
+          def through_reflection
+            reflection.through_reflection
           end
 
-          reset_association owners, through_reflection.name
-
-          middle_records = through_records.flat_map { |(_,rec)| rec }
-
-          preloaders = preloader.preload(middle_records,
-                                         source_reflection.name,
-                                         reflection_scope)
-
-          @preloaded_records = preloaders.flat_map(&:preloaded_records)
+          def source_reflection
+            reflection.source_reflection
+          end
 
-          middle_to_pl = preloaders.each_with_object({}) do |pl,h|
-            pl.owners.each { |middle|
-              h[middle] = pl
-            }
+          def preload_index
+            @preload_index ||= @preloaded_records.each_with_object({}).with_index do |(id, result), index|
+              result[id] = index
+            end
           end
 
-          through_records.each_with_object({}) do |(lhs,center), records_by_owner|
-            pl_to_middle = center.group_by { |record| middle_to_pl[record] }
+          def through_scope
+            scope = through_reflection.klass.unscoped
+            options = reflection.options
 
-            records_by_owner[lhs] = pl_to_middle.flat_map do |pl, middles|
-              rhs_records = middles.flat_map { |r|
-                association = r.association source_reflection.name
+            if options[:source_type]
+              scope.where! reflection.foreign_type => options[:source_type]
+            elsif !reflection_scope.where_clause.empty?
+              scope.where_clause = reflection_scope.where_clause
+              values = reflection_scope.values
 
-                target_records_from_association(association)
-              }.compact
+              if includes = values[:includes]
+                scope.includes!(source_reflection.name => includes)
+              else
+                scope.includes!(source_reflection.name)
+              end
 
-              # Respect the order on `reflection_scope` if it exists, else use the natural order.
-              if reflection_scope.values[:order].present?
-                @id_map ||= id_to_index_map @preloaded_records
-                rhs_records.sort_by { |rhs| @id_map[rhs] }
+              if values[:references] && !values[:references].empty?
+                scope.references!(values[:references])
               else
-                rhs_records
+                scope.references!(source_reflection.table_name)
               end
-            end
-          end
-        end
 
-        private
+              if joins = values[:joins]
+                scope.joins!(source_reflection.name => joins)
+              end
 
-        def id_to_index_map(ids)
-          id_map = {}
-          ids.each_with_index { |id, index| id_map[id] = index }
-          id_map
-        end
+              if left_outer_joins = values[:left_outer_joins]
+                scope.left_outer_joins!(source_reflection.name => left_outer_joins)
+              end
 
-        def reset_association(owners, association_name)
-          should_reset = (through_scope != through_reflection.klass.unscoped) ||
-             (reflection.options[:source_type] && through_reflection.collection?)
+              if scope.eager_loading? && order_values = values[:order]
+                scope = scope.order(order_values)
+              end
+            end
 
-          # Don't cache the association - we would only be caching a subset
-          if should_reset
-            owners.each { |owner|
-              owner.association(association_name).reset
-            }
+            scope unless scope.empty_scope?
           end
-        end
 
-
-        def through_scope
-          scope = through_reflection.klass.unscoped
-
-          if options[:source_type]
-            scope.where! reflection.foreign_type => options[:source_type]
-          else
-            unless reflection_scope.where_clause.empty?
-              scope.includes_values = Array(reflection_scope.values[:includes] || options[:source])
-              scope.where_clause = reflection_scope.where_clause
-            end
-
-            scope.references! reflection_scope.values[:references]
-            if scope.eager_loading? && order_values = reflection_scope.values[:order]
-              scope = scope.order(order_values)
+          def target_reflection_scope
+            if preload_scope
+              reflection_scope.merge(preload_scope)
+            elsif reflection.scope
+              reflection_scope
+            else
+              nil
             end
           end
-
-          scope
-        end
-
-        def target_records_from_association(association)
-          association.loaded? ? association.target : association.reader
-        end
       end
     end
   end
diff --git a/activerecord/lib/active_record/associations/singular_association.rb b/activerecord/lib/active_record/associations/singular_association.rb
index f913f0852a..441bd715e4 100644
--- a/activerecord/lib/active_record/associations/singular_association.rb
+++ b/activerecord/lib/active_record/associations/singular_association.rb
@@ -1,17 +1,11 @@
+# frozen_string_literal: true
+
 module ActiveRecord
   module Associations
     class SingularAssociation < Association #:nodoc:
       # Implements the reader method, e.g. foo.bar for Foo.has_one :bar
-      def reader(force_reload = false)
-        if force_reload && klass
-          ActiveSupport::Deprecation.warn(<<-MSG.squish)
-            Passing an argument to force an association to reload is now
-            deprecated and will be removed in Rails 5.1. Please call `reload`
-            on the parent object instead.
-          MSG
-
-          klass.uncached { reload }
-        elsif !loaded? || stale_target?
+      def reader
+        if !loaded? || stale_target?
           reload
         end
 
@@ -23,14 +17,6 @@ module ActiveRecord
         replace(record)
       end
 
-      def create(attributes = {}, &block)
-        _create_record(attributes, &block)
-      end
-
-      def create!(attributes = {}, &block)
-        _create_record(attributes, true, &block)
-      end
-
       def build(attributes = {})
         record = build_record(attributes)
         yield(record) if block_given?
@@ -38,31 +24,34 @@ module ActiveRecord
         record
       end
 
-      private
+      # Implements the reload reader method, e.g. foo.reload_bar for
+      # Foo.has_one :bar
+      def force_reload_reader
+        klass.uncached { reload }
+        target
+      end
 
-        def create_scope
-          scope.scope_for_create.stringify_keys.except(klass.primary_key)
+      private
+        def scope_for_create
+          super.except!(klass.primary_key)
         end
 
-        def get_records
-          return scope.limit(1).records if skip_statement_cache?
+        def find_target
+          scope = self.scope
+          return scope.take if skip_statement_cache?(scope)
 
           conn = klass.connection
-          sc = reflection.association_scope_cache(conn, owner) do
-            StatementCache.create(conn) { |params|
-              as = AssociationScope.create { params.bind }
-              target_scope.merge(as.scope(self, conn)).limit(1)
-            }
+          sc = reflection.association_scope_cache(conn, owner) do |params|
+            as = AssociationScope.create { params.bind }
+            target_scope.merge!(as.scope(self)).limit(1)
           end
 
           binds = AssociationScope.get_bind_values(owner, reflection.chain)
-          sc.execute binds, klass, klass.connection
-        end
-
-        def find_target
-          if record = get_records.first
+          sc.execute(binds, conn) do |record|
             set_inverse_instance record
-          end
+          end.first
+        rescue ::RangeError
+          nil
         end
 
         def replace(record)
@@ -74,6 +63,10 @@ module ActiveRecord
         end
 
         def _create_record(attributes, raise_error = false)
+          unless owner.persisted?
+            raise ActiveRecord::RecordNotSaved, "You cannot call create unless the parent is saved"
+          end
+
           record = build_record(attributes)
           yield(record) if block_given?
           saved = record.save
diff --git a/activerecord/lib/active_record/associations/through_association.rb b/activerecord/lib/active_record/associations/through_association.rb
index d0ec3e8015..bce2a95ce1 100644
--- a/activerecord/lib/active_record/associations/through_association.rb
+++ b/activerecord/lib/active_record/associations/through_association.rb
@@ -1,11 +1,12 @@
+# frozen_string_literal: true
+
 module ActiveRecord
-  # = Active Record Through Association
   module Associations
+    # = Active Record Through Association
     module ThroughAssociation #:nodoc:
+      delegate :source_reflection, :through_reflection, to: :reflection
 
-      delegate :source_reflection, :through_reflection, :to => :reflection
-
-      protected
+      private
 
         # We merge in these scopes for two reasons:
         #
@@ -14,7 +15,7 @@ module ActiveRecord
         def target_scope
           scope = super
           reflection.chain.drop(1).each do |reflection|
-            relation = reflection.klass.all
+            relation = reflection.klass.scope_for_association
             scope.merge!(
               relation.except(:select, :create_with, :includes, :preload, :joins, :eager_load)
             )
@@ -22,8 +23,6 @@ module ActiveRecord
           scope
         end
 
-      private
-
         # Construct attributes for :through pointing to owner and associate. This is used by the
         # methods which create and delete records on the association.
         #
diff --git a/activerecord/lib/active_record/attribute_assignment.rb b/activerecord/lib/active_record/attribute_assignment.rb
index b96d8e9352..8b0d9aab01 100644
--- a/activerecord/lib/active_record/attribute_assignment.rb
+++ b/activerecord/lib/active_record/attribute_assignment.rb
@@ -1,4 +1,6 @@
-require 'active_model/forbidden_attributes_protection'
+# frozen_string_literal: true
+
+require "active_model/forbidden_attributes_protection"
 
 module ActiveRecord
   module AttributeAssignment
@@ -12,80 +14,80 @@ module ActiveRecord
 
     private
 
-    def _assign_attributes(attributes) # :nodoc:
-      multi_parameter_attributes  = {}
-      nested_parameter_attributes = {}
+      def _assign_attributes(attributes)
+        multi_parameter_attributes  = {}
+        nested_parameter_attributes = {}
 
-      attributes.each do |k, v|
-        if k.include?("(")
-          multi_parameter_attributes[k] = attributes.delete(k)
-        elsif v.is_a?(Hash)
-          nested_parameter_attributes[k] = attributes.delete(k)
+        attributes.each do |k, v|
+          if k.include?("(")
+            multi_parameter_attributes[k] = attributes.delete(k)
+          elsif v.is_a?(Hash)
+            nested_parameter_attributes[k] = attributes.delete(k)
+          end
         end
-      end
-      super(attributes)
+        super(attributes)
 
-      assign_nested_parameter_attributes(nested_parameter_attributes) unless nested_parameter_attributes.empty?
-      assign_multiparameter_attributes(multi_parameter_attributes) unless multi_parameter_attributes.empty?
-    end
+        assign_nested_parameter_attributes(nested_parameter_attributes) unless nested_parameter_attributes.empty?
+        assign_multiparameter_attributes(multi_parameter_attributes) unless multi_parameter_attributes.empty?
+      end
 
-    # Assign any deferred nested attributes after the base attributes have been set.
-    def assign_nested_parameter_attributes(pairs)
-      pairs.each { |k, v| _assign_attribute(k, v) }
-    end
+      # Assign any deferred nested attributes after the base attributes have been set.
+      def assign_nested_parameter_attributes(pairs)
+        pairs.each { |k, v| _assign_attribute(k, v) }
+      end
 
-    # Instantiates objects for all attribute classes that needs more than one constructor parameter. This is done
-    # by calling new on the column type or aggregation type (through composed_of) object with these parameters.
-    # So having the pairs written_on(1) = "2004", written_on(2) = "6", written_on(3) = "24", will instantiate
-    # written_on (a date type) with Date.new("2004", "6", "24"). You can also specify a typecast character in the
-    # parentheses to have the parameters typecasted before they're used in the constructor. Use i for Integer and
-    # f for Float. If all the values for a given attribute are empty, the attribute will be set to +nil+.
-    def assign_multiparameter_attributes(pairs)
-      execute_callstack_for_multiparameter_attributes(
-        extract_callstack_for_multiparameter_attributes(pairs)
-      )
-    end
+      # Instantiates objects for all attribute classes that needs more than one constructor parameter. This is done
+      # by calling new on the column type or aggregation type (through composed_of) object with these parameters.
+      # So having the pairs written_on(1) = "2004", written_on(2) = "6", written_on(3) = "24", will instantiate
+      # written_on (a date type) with Date.new("2004", "6", "24"). You can also specify a typecast character in the
+      # parentheses to have the parameters typecasted before they're used in the constructor. Use i for Integer and
+      # f for Float. If all the values for a given attribute are empty, the attribute will be set to +nil+.
+      def assign_multiparameter_attributes(pairs)
+        execute_callstack_for_multiparameter_attributes(
+          extract_callstack_for_multiparameter_attributes(pairs)
+        )
+      end
 
-    def execute_callstack_for_multiparameter_attributes(callstack)
-      errors = []
-      callstack.each do |name, values_with_empty_parameters|
-        begin
-          if values_with_empty_parameters.each_value.all?(&:nil?)
-            values = nil
-          else
-            values = values_with_empty_parameters
+      def execute_callstack_for_multiparameter_attributes(callstack)
+        errors = []
+        callstack.each do |name, values_with_empty_parameters|
+          begin
+            if values_with_empty_parameters.each_value.all?(&:nil?)
+              values = nil
+            else
+              values = values_with_empty_parameters
+            end
+            send("#{name}=", values)
+          rescue => ex
+            errors << AttributeAssignmentError.new("error on assignment #{values_with_empty_parameters.values.inspect} to #{name} (#{ex.message})", ex, name)
           end
-          send("#{name}=", values)
-        rescue => ex
-          errors << AttributeAssignmentError.new("error on assignment #{values_with_empty_parameters.values.inspect} to #{name} (#{ex.message})", ex, name)
+        end
+        unless errors.empty?
+          error_descriptions = errors.map(&:message).join(",")
+          raise MultiparameterAssignmentErrors.new(errors), "#{errors.size} error(s) on assignment of multiparameter attributes [#{error_descriptions}]"
         end
       end
-      unless errors.empty?
-        error_descriptions = errors.map(&:message).join(",")
-        raise MultiparameterAssignmentErrors.new(errors), "#{errors.size} error(s) on assignment of multiparameter attributes [#{error_descriptions}]"
-      end
-    end
 
-    def extract_callstack_for_multiparameter_attributes(pairs)
-      attributes = {}
+      def extract_callstack_for_multiparameter_attributes(pairs)
+        attributes = {}
 
-      pairs.each do |(multiparameter_name, value)|
-        attribute_name = multiparameter_name.split("(").first
-        attributes[attribute_name] ||= {}
+        pairs.each do |(multiparameter_name, value)|
+          attribute_name = multiparameter_name.split("(").first
+          attributes[attribute_name] ||= {}
 
-        parameter_value = value.empty? ? nil : type_cast_attribute_value(multiparameter_name, value)
-        attributes[attribute_name][find_parameter_position(multiparameter_name)] ||= parameter_value
-      end
+          parameter_value = value.empty? ? nil : type_cast_attribute_value(multiparameter_name, value)
+          attributes[attribute_name][find_parameter_position(multiparameter_name)] ||= parameter_value
+        end
 
-      attributes
-    end
+        attributes
+      end
 
-    def type_cast_attribute_value(multiparameter_name, value)
-      multiparameter_name =~ /\([0-9]*([if])\)/ ? value.send("to_" + $1) : value
-    end
+      def type_cast_attribute_value(multiparameter_name, value)
+        multiparameter_name =~ /\([0-9]*([if])\)/ ? value.send("to_" + $1) : value
+      end
 
-    def find_parameter_position(multiparameter_name)
-      multiparameter_name.scan(/\(([0-9]*).*\)/).first.first.to_i
-    end
+      def find_parameter_position(multiparameter_name)
+        multiparameter_name.scan(/\(([0-9]*).*\)/).first.first.to_i
+      end
   end
 end
diff --git a/activerecord/lib/active_record/attribute_decorators.rb b/activerecord/lib/active_record/attribute_decorators.rb
index 7d0ae32411..98b7805c0a 100644
--- a/activerecord/lib/active_record/attribute_decorators.rb
+++ b/activerecord/lib/active_record/attribute_decorators.rb
@@ -1,19 +1,42 @@
+# frozen_string_literal: true
+
 module ActiveRecord
   module AttributeDecorators # :nodoc:
     extend ActiveSupport::Concern
 
     included do
-      class_attribute :attribute_type_decorations, instance_accessor: false # :internal:
-      self.attribute_type_decorations = TypeDecorator.new
+      class_attribute :attribute_type_decorations, instance_accessor: false, default: TypeDecorator.new # :internal:
     end
 
     module ClassMethods # :nodoc:
+      # This method is an internal API used to create class macros such as
+      # +serialize+, and features like time zone aware attributes.
+      #
+      # Used to wrap the type of an attribute in a new type.
+      # When the schema for a model is loaded, attributes with the same name as
+      # +column_name+ will have their type yielded to the given block. The
+      # return value of that block will be used instead.
+      #
+      # Subsequent calls where +column_name+ and +decorator_name+ are the same
+      # will override the previous decorator, not decorate twice. This can be
+      # used to create idempotent class macros like +serialize+
       def decorate_attribute_type(column_name, decorator_name, &block)
         matcher = ->(name, _) { name == column_name.to_s }
         key = "_#{column_name}_#{decorator_name}"
         decorate_matching_attribute_types(matcher, key, &block)
       end
 
+      # This method is an internal API used to create higher level features like
+      # time zone aware attributes.
+      #
+      # When the schema for a model is loaded, +matcher+ will be called for each
+      # attribute with its name and type. If the matcher returns a truthy value,
+      # the type will then be yielded to the given block, and the return value
+      # of that block will replace the type.
+      #
+      # Subsequent calls to this method with the same value for +decorator_name+
+      # will replace the previous decorator, not decorate twice. This can be
+      # used to ensure that class macros are idempotent.
       def decorate_matching_attribute_types(matcher, decorator_name, &block)
         reload_schema_from_cache
         decorator_name = decorator_name.to_s
@@ -24,13 +47,13 @@ module ActiveRecord
 
       private
 
-      def load_schema!
-        super
-        attribute_types.each do |name, type|
-          decorated_type = attribute_type_decorations.apply(name, type)
-          define_attribute(name, decorated_type)
+        def load_schema!
+          super
+          attribute_types.each do |name, type|
+            decorated_type = attribute_type_decorations.apply(name, type)
+            define_attribute(name, decorated_type)
+          end
         end
-      end
     end
 
     class TypeDecorator # :nodoc:
@@ -53,15 +76,15 @@ module ActiveRecord
 
       private
 
-      def decorators_for(name, type)
-        matching(name, type).map(&:last)
-      end
+        def decorators_for(name, type)
+          matching(name, type).map(&:last)
+        end
 
-      def matching(name, type)
-        @decorations.values.select do |(matcher, _)|
-          matcher.call(name, type)
+        def matching(name, type)
+          @decorations.values.select do |(matcher, _)|
+            matcher.call(name, type)
+          end
         end
-      end
     end
   end
 end
diff --git a/activerecord/lib/active_record/attribute_methods.rb b/activerecord/lib/active_record/attribute_methods.rb
index 1fb5eb28cd..64f81ca582 100644
--- a/activerecord/lib/active_record/attribute_methods.rb
+++ b/activerecord/lib/active_record/attribute_methods.rb
@@ -1,7 +1,6 @@
-require 'active_support/core_ext/enumerable'
-require 'active_support/core_ext/string/filters'
-require 'mutex_m'
-require 'concurrent/map'
+# frozen_string_literal: true
+
+require "mutex_m"
 
 module ActiveRecord
   # = Active Record Attribute Methods
@@ -34,7 +33,9 @@ module ActiveRecord
 
     BLACKLISTED_CLASS_METHODS = %w(private public protected allocate new name parent superclass)
 
-    class GeneratedAttributeMethods < Module; end # :nodoc:
+    class GeneratedAttributeMethods < Module #:nodoc:
+      include Mutex_m
+    end
 
     module ClassMethods
       def inherited(child_class) #:nodoc:
@@ -43,7 +44,7 @@ module ActiveRecord
       end
 
       def initialize_generated_modules # :nodoc:
-        @generated_attribute_methods = GeneratedAttributeMethods.new { extend Mutex_m }
+        @generated_attribute_methods = GeneratedAttributeMethods.new
         @attribute_methods_generated = false
         include @generated_attribute_methods
 
@@ -62,7 +63,6 @@ module ActiveRecord
           super(attribute_names)
           @attribute_methods_generated = true
         end
-        true
       end
 
       def undefine_attribute_methods # :nodoc:
@@ -148,7 +148,7 @@ module ActiveRecord
       #   Person.attribute_method?(:age=)    # => true
       #   Person.attribute_method?(:nothing) # => false
       def attribute_method?(attribute)
-        super || (table_exists? && column_names.include?(attribute.to_s.sub(/=$/, '')))
+        super || (table_exists? && column_names.include?(attribute.to_s.sub(/=$/, "")))
       end
 
       # Returns an array of column names as strings if it's not an abstract class and
@@ -161,10 +161,50 @@ module ActiveRecord
       #   # => ["id", "created_at", "updated_at", "name", "age"]
       def attribute_names
         @attribute_names ||= if !abstract_class? && table_exists?
-            attribute_types.keys
-          else
-            []
-          end
+          attribute_types.keys
+        else
+          []
+        end
+      end
+
+      # Regexp whitelist. Matches the following:
+      #   "#{table_name}.#{column_name}"
+      #   "#{column_name}"
+      COLUMN_NAME_WHITELIST = /\A(?:\w+\.)?\w+\z/i
+
+      # Regexp whitelist. Matches the following:
+      #   "#{table_name}.#{column_name}"
+      #   "#{table_name}.#{column_name} #{direction}"
+      #   "#{column_name}"
+      #   "#{column_name} #{direction}"
+      COLUMN_NAME_ORDER_WHITELIST = /\A(?:\w+\.)?\w+(?:\s+asc|\s+desc)?\z/i
+
+      def enforce_raw_sql_whitelist(args, whitelist: COLUMN_NAME_WHITELIST) # :nodoc:
+        unexpected = args.reject do |arg|
+          arg.kind_of?(Arel::Node) ||
+            arg.is_a?(Arel::Nodes::SqlLiteral) ||
+            arg.is_a?(Arel::Attributes::Attribute) ||
+            arg.to_s.split(/\s*,\s*/).all? { |part| whitelist.match?(part) }
+        end
+
+        return if unexpected.none?
+
+        if allow_unsafe_raw_sql == :deprecated
+          ActiveSupport::Deprecation.warn(
+            "Dangerous query method (method whose arguments are used as raw " \
+            "SQL) called with non-attribute argument(s): " \
+            "#{unexpected.map(&:inspect).join(", ")}. Non-attribute " \
+            "arguments will be disallowed in Rails 6.0. This method should " \
+            "not be called with user-provided values, such as request " \
+            "parameters or model attributes. Known-safe values can be passed " \
+            "by wrapping them in Arel.sql()."
+          )
+        else
+          raise(ActiveRecord::UnknownAttributeReference,
+            "Query method called with non-attribute argument(s): " +
+            unexpected.map(&:inspect).join(", ")
+          )
+        end
       end
 
       # Returns true if the given attribute exists, otherwise false.
@@ -209,13 +249,13 @@ module ActiveRecord
     #   end
     #
     #   person = Person.new
-    #   person.respond_to(:name)    # => true
-    #   person.respond_to(:name=)   # => true
-    #   person.respond_to(:name?)   # => true
-    #   person.respond_to('age')    # => true
-    #   person.respond_to('age=')   # => true
-    #   person.respond_to('age?')   # => true
-    #   person.respond_to(:nothing) # => false
+    #   person.respond_to?(:name)    # => true
+    #   person.respond_to?(:name=)   # => true
+    #   person.respond_to?(:name?)   # => true
+    #   person.respond_to?('age')    # => true
+    #   person.respond_to?('age=')   # => true
+    #   person.respond_to?('age?')   # => true
+    #   person.respond_to?(:nothing) # => false
     def respond_to?(name, include_private = false)
       return false unless super
 
@@ -236,7 +276,7 @@ module ActiveRecord
         return has_attribute?(name)
       end
 
-      return true
+      true
     end
 
     # Returns +true+ if the given attribute is in the attributes hash, otherwise +false+.
@@ -279,9 +319,8 @@ module ActiveRecord
     # Returns an <tt>#inspect</tt>-like string for the value of the
     # attribute +attr_name+. String attributes are truncated up to 50
     # characters, Date and Time attributes are returned in the
-    # <tt>:db</tt> format, Array attributes are truncated up to 10 values.
-    # Other attributes return the value of <tt>#inspect</tt> without
-    # modification.
+    # <tt>:db</tt> format. Other attributes return the value of
+    # <tt>#inspect</tt> without modification.
     #
     #   person = Person.create!(name: 'David Heinemeier Hansson ' * 3)
     #
@@ -292,7 +331,7 @@ module ActiveRecord
     #   # => "\"2012-10-22 00:15:07\""
     #
     #   person.attribute_for_inspect(:tag_ids)
-    #   # => "[1, 2, 3, 4, 5, 6, 7, 8, 9, 10, ...]"
+    #   # => "[1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11]"
     def attribute_for_inspect(attr_name)
       value = read_attribute(attr_name)
 
@@ -300,9 +339,6 @@ module ActiveRecord
         "#{value[0, 50]}...".inspect
       elsif value.is_a?(Date) || value.is_a?(Time)
         %("#{value.to_s(:db)}")
-      elsif value.is_a?(Array) && value.size > 10
-        inspected = value.first(10).inspect
-        %(#{inspected[0...-1]}, ...])
       else
         value.inspect
       end
@@ -398,65 +434,58 @@ module ActiveRecord
 
     protected
 
-    def clone_attribute_value(reader_method, attribute_name) # :nodoc:
-      value = send(reader_method, attribute_name)
-      value.duplicable? ? value.clone : value
-    rescue TypeError, NoMethodError
-      value
-    end
-
-    def arel_attributes_with_values_for_create(attribute_names) # :nodoc:
-      arel_attributes_with_values(attributes_for_create(attribute_names))
-    end
+      def attribute_method?(attr_name) # :nodoc:
+        # We check defined? because Syck calls respond_to? before actually calling initialize.
+        defined?(@attributes) && @attributes.key?(attr_name)
+      end
 
-    def arel_attributes_with_values_for_update(attribute_names) # :nodoc:
-      arel_attributes_with_values(attributes_for_update(attribute_names))
-    end
+    private
 
-    def attribute_method?(attr_name) # :nodoc:
-      # We check defined? because Syck calls respond_to? before actually calling initialize.
-      defined?(@attributes) && @attributes.key?(attr_name)
-    end
+      def arel_attributes_with_values_for_create(attribute_names)
+        arel_attributes_with_values(attributes_for_create(attribute_names))
+      end
 
-    private
+      def arel_attributes_with_values_for_update(attribute_names)
+        arel_attributes_with_values(attributes_for_update(attribute_names))
+      end
 
-    # Returns a Hash of the Arel::Attributes and attribute values that have been
-    # typecasted for use in an Arel insert/update method.
-    def arel_attributes_with_values(attribute_names)
-      attrs = {}
-      arel_table = self.class.arel_table
+      # Returns a Hash of the Arel::Attributes and attribute values that have been
+      # typecasted for use in an Arel insert/update method.
+      def arel_attributes_with_values(attribute_names)
+        attrs = {}
+        arel_table = self.class.arel_table
 
-      attribute_names.each do |name|
-        attrs[arel_table[name]] = typecasted_attribute_value(name)
+        attribute_names.each do |name|
+          attrs[arel_table[name]] = typecasted_attribute_value(name)
+        end
+        attrs
       end
-      attrs
-    end
 
-    # Filters the primary keys and readonly attributes from the attribute names.
-    def attributes_for_update(attribute_names)
-      attribute_names.reject do |name|
-        readonly_attribute?(name)
+      # Filters the primary keys and readonly attributes from the attribute names.
+      def attributes_for_update(attribute_names)
+        attribute_names.reject do |name|
+          readonly_attribute?(name)
+        end
       end
-    end
 
-    # Filters out the primary keys, from the attribute names, when the primary
-    # key is to be generated (e.g. the id attribute has no value).
-    def attributes_for_create(attribute_names)
-      attribute_names.reject do |name|
-        pk_attribute?(name) && id.nil?
+      # Filters out the primary keys, from the attribute names, when the primary
+      # key is to be generated (e.g. the id attribute has no value).
+      def attributes_for_create(attribute_names)
+        attribute_names.reject do |name|
+          pk_attribute?(name) && id.nil?
+        end
       end
-    end
 
-    def readonly_attribute?(name)
-      self.class.readonly_attributes.include?(name)
-    end
+      def readonly_attribute?(name)
+        self.class.readonly_attributes.include?(name)
+      end
 
-    def pk_attribute?(name)
-      name == self.class.primary_key
-    end
+      def pk_attribute?(name)
+        name == self.class.primary_key
+      end
 
-    def typecasted_attribute_value(name)
-      _read_attribute(name)
-    end
+      def typecasted_attribute_value(name)
+        _read_attribute(name)
+      end
   end
 end
diff --git a/activerecord/lib/active_record/attribute_methods/before_type_cast.rb b/activerecord/lib/active_record/attribute_methods/before_type_cast.rb
index 1db6776688..5941f51a1a 100644
--- a/activerecord/lib/active_record/attribute_methods/before_type_cast.rb
+++ b/activerecord/lib/active_record/attribute_methods/before_type_cast.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActiveRecord
   module AttributeMethods
     # = Active Record Attribute Methods Before Type Cast
@@ -63,14 +65,14 @@ module ActiveRecord
 
       private
 
-      # Handle *_before_type_cast for method_missing.
-      def attribute_before_type_cast(attribute_name)
-        read_attribute_before_type_cast(attribute_name)
-      end
+        # Handle *_before_type_cast for method_missing.
+        def attribute_before_type_cast(attribute_name)
+          read_attribute_before_type_cast(attribute_name)
+        end
 
-      def attribute_came_from_user?(attribute_name)
-        @attributes[attribute_name].came_from_user?
-      end
+        def attribute_came_from_user?(attribute_name)
+          @attributes[attribute_name].came_from_user?
+        end
     end
   end
 end
diff --git a/activerecord/lib/active_record/attribute_methods/dirty.rb b/activerecord/lib/active_record/attribute_methods/dirty.rb
index 0bcfa5f00d..3de6fe566d 100644
--- a/activerecord/lib/active_record/attribute_methods/dirty.rb
+++ b/activerecord/lib/active_record/attribute_methods/dirty.rb
@@ -1,9 +1,10 @@
-require 'active_support/core_ext/module/attribute_accessors'
-require 'active_record/attribute_mutation_tracker'
+# frozen_string_literal: true
+
+require "active_support/core_ext/module/attribute_accessors"
 
 module ActiveRecord
   module AttributeMethods
-    module Dirty # :nodoc:
+    module Dirty
       extend ActiveSupport::Concern
 
       include ActiveModel::Dirty
@@ -13,139 +14,132 @@ module ActiveRecord
           raise "You cannot include Dirty after Timestamp"
         end
 
-        class_attribute :partial_writes, instance_writer: false
-        self.partial_writes = true
-      end
+        class_attribute :partial_writes, instance_writer: false, default: true
 
-      # Attempts to +save+ the record and clears changed attributes if successful.
-      def save(*)
-        if status = super
-          changes_applied
-        end
-        status
-      end
+        after_create { changes_applied }
+        after_update { changes_applied }
 
-      # Attempts to <tt>save!</tt> the record and clears changed attributes if successful.
-      def save!(*)
-        super.tap do
-          changes_applied
-        end
+        # Attribute methods for "changed in last call to save?"
+        attribute_method_affix(prefix: "saved_change_to_", suffix: "?")
+        attribute_method_prefix("saved_change_to_")
+        attribute_method_suffix("_before_last_save")
+
+        # Attribute methods for "will change if I call save?"
+        attribute_method_affix(prefix: "will_save_change_to_", suffix: "?")
+        attribute_method_suffix("_change_to_be_saved", "_in_database")
       end
 
       # <tt>reload</tt> the record and clears changed attributes.
       def reload(*)
         super.tap do
-          @mutation_tracker = nil
-          @previous_mutation_tracker = nil
-          @changed_attributes = HashWithIndifferentAccess.new
+          @previously_changed = ActiveSupport::HashWithIndifferentAccess.new
+          @mutations_before_last_save = nil
+          @attributes_changed_by_setter = ActiveSupport::HashWithIndifferentAccess.new
+          @mutations_from_database = nil
         end
       end
 
-      def initialize_dup(other) # :nodoc:
-        super
-        @attributes = self.class._default_attributes.map do |attr|
-          attr.with_value_from_user(@attributes.fetch_value(attr.name))
-        end
-        @mutation_tracker = nil
+      # Did this attribute change when we last saved? This method can be invoked
+      # as +saved_change_to_name?+ instead of <tt>saved_change_to_attribute?("name")</tt>.
+      # Behaves similarly to +attribute_changed?+. This method is useful in
+      # after callbacks to determine if the call to save changed a certain
+      # attribute.
+      #
+      # ==== Options
+      #
+      # +from+ When passed, this method will return false unless the original
+      # value is equal to the given option
+      #
+      # +to+ When passed, this method will return false unless the value was
+      # changed to the given value
+      def saved_change_to_attribute?(attr_name, **options)
+        mutations_before_last_save.changed?(attr_name, **options)
       end
 
-      def changes_applied
-        @previous_mutation_tracker = mutation_tracker
-        @changed_attributes = HashWithIndifferentAccess.new
-        store_original_attributes
+      # Returns the change to an attribute during the last save. If the
+      # attribute was changed, the result will be an array containing the
+      # original value and the saved value.
+      #
+      # Behaves similarly to +attribute_change+. This method is useful in after
+      # callbacks, to see the change in an attribute that just occurred
+      #
+      # This method can be invoked as +saved_change_to_name+ in instead of
+      # <tt>saved_change_to_attribute("name")</tt>
+      def saved_change_to_attribute(attr_name)
+        mutations_before_last_save.change_to_attribute(attr_name)
       end
 
-      def clear_changes_information
-        @previous_mutation_tracker = nil
-        @changed_attributes = HashWithIndifferentAccess.new
-        store_original_attributes
+      # Returns the original value of an attribute before the last save.
+      # Behaves similarly to +attribute_was+. This method is useful in after
+      # callbacks to get the original value of an attribute before the save that
+      # just occurred
+      def attribute_before_last_save(attr_name)
+        mutations_before_last_save.original_value(attr_name)
       end
 
-      def raw_write_attribute(attr_name, *)
-        result = super
-        clear_attribute_change(attr_name)
-        result
+      # Did the last call to +save+ have any changes to change?
+      def saved_changes?
+        mutations_before_last_save.any_changes?
       end
 
-      def clear_attribute_changes(attr_names)
-        super
-        attr_names.each do |attr_name|
-          clear_attribute_change(attr_name)
-        end
+      # Returns a hash containing all the changes that were just saved.
+      def saved_changes
+        mutations_before_last_save.changes
       end
 
-      def changed_attributes
-        # This should only be set by methods which will call changed_attributes
-        # multiple times when it is known that the computed value cannot change.
-        if defined?(@cached_changed_attributes)
-          @cached_changed_attributes
-        else
-          super.reverse_merge(mutation_tracker.changed_values).freeze
-        end
+      # Alias for +attribute_changed?+
+      def will_save_change_to_attribute?(attr_name, **options)
+        mutations_from_database.changed?(attr_name, **options)
       end
 
-      def changes
-        cache_changed_attributes do
-          super
-        end
+      # Alias for +attribute_change+
+      def attribute_change_to_be_saved(attr_name)
+        mutations_from_database.change_to_attribute(attr_name)
       end
 
-      def previous_changes
-        previous_mutation_tracker.changes
+      # Alias for +attribute_was+
+      def attribute_in_database(attr_name)
+        mutations_from_database.original_value(attr_name)
       end
 
-      def attribute_changed_in_place?(attr_name)
-        mutation_tracker.changed_in_place?(attr_name)
+      # Alias for +changed?+
+      def has_changes_to_save?
+        mutations_from_database.any_changes?
       end
 
-      private
-
-      def mutation_tracker
-        unless defined?(@mutation_tracker)
-          @mutation_tracker = nil
-        end
-        @mutation_tracker ||= AttributeMutationTracker.new(@attributes)
+      # Alias for +changes+
+      def changes_to_save
+        mutations_from_database.changes
       end
 
-      def changes_include?(attr_name)
-        super || mutation_tracker.changed?(attr_name)
+      # Alias for +changed+
+      def changed_attribute_names_to_save
+        changes_to_save.keys
       end
 
-      def clear_attribute_change(attr_name)
-        mutation_tracker.forget_change(attr_name)
+      # Alias for +changed_attributes+
+      def attributes_in_database
+        changes_to_save.transform_values(&:first)
       end
 
-      def _update_record(*)
-        partial_writes? ? super(keys_for_partial_write) : super
-      end
-
-      def _create_record(*)
-        partial_writes? ? super(keys_for_partial_write) : super
-      end
-
-      def keys_for_partial_write
-        changed & self.class.column_names
-      end
-
-      def store_original_attributes
-        @attributes = @attributes.map(&:forgetting_assignment)
-        @mutation_tracker = nil
-      end
+      private
+        def write_attribute_without_type_cast(attr_name, _)
+          result = super
+          clear_attribute_change(attr_name)
+          result
+        end
 
-      def previous_mutation_tracker
-        @previous_mutation_tracker ||= NullMutationTracker.instance
-      end
+        def _update_record(*)
+          partial_writes? ? super(keys_for_partial_write) : super
+        end
 
-      def cache_changed_attributes
-        @cached_changed_attributes = changed_attributes
-        yield
-      ensure
-        clear_changed_attributes_cache
-      end
+        def _create_record(*)
+          partial_writes? ? super(keys_for_partial_write) : super
+        end
 
-      def clear_changed_attributes_cache
-        remove_instance_variable(:@cached_changed_attributes) if defined?(@cached_changed_attributes)
-      end
+        def keys_for_partial_write
+          changed_attribute_names_to_save & self.class.column_names
+        end
     end
   end
 end
diff --git a/activerecord/lib/active_record/attribute_methods/primary_key.rb b/activerecord/lib/active_record/attribute_methods/primary_key.rb
index 0d5cb8b37c..d8fc046e10 100644
--- a/activerecord/lib/active_record/attribute_methods/primary_key.rb
+++ b/activerecord/lib/active_record/attribute_methods/primary_key.rb
@@ -1,4 +1,6 @@
-require 'set'
+# frozen_string_literal: true
+
+require "set"
 
 module ActiveRecord
   module AttributeMethods
@@ -8,23 +10,22 @@ module ActiveRecord
       # Returns this record's primary key value wrapped in an array if one is
       # available.
       def to_key
-        sync_with_transaction_state
-        key = self.id
+        key = id
         [key] if key
       end
 
       # Returns the primary key value.
       def id
-        if pk = self.class.primary_key
-          sync_with_transaction_state
-          _read_attribute(pk)
-        end
+        sync_with_transaction_state
+        primary_key = self.class.primary_key
+        _read_attribute(primary_key) if primary_key
       end
 
       # Sets the primary key value.
       def id=(value)
         sync_with_transaction_state
-        write_attribute(self.class.primary_key, value) if self.class.primary_key
+        primary_key = self.class.primary_key
+        _write_attribute(primary_key, value) if primary_key
       end
 
       # Queries the primary key value.
@@ -45,84 +46,98 @@ module ActiveRecord
         attribute_was(self.class.primary_key)
       end
 
-      protected
-
-      def attribute_method?(attr_name)
-        attr_name == 'id' || super
+      def id_in_database
+        sync_with_transaction_state
+        attribute_in_database(self.class.primary_key)
       end
 
-      module ClassMethods
-        def define_method_attribute(attr_name)
-          super
+      private
 
-          if attr_name == primary_key && attr_name != 'id'
-            generated_attribute_methods.send(:alias_method, :id, primary_key)
-          end
+        def attribute_method?(attr_name)
+          attr_name == "id" || super
         end
 
-        ID_ATTRIBUTE_METHODS = %w(id id= id? id_before_type_cast id_was).to_set
+        module ClassMethods
+          ID_ATTRIBUTE_METHODS = %w(id id= id? id_before_type_cast id_was id_in_database).to_set
 
-        def dangerous_attribute_method?(method_name)
-          super && !ID_ATTRIBUTE_METHODS.include?(method_name)
-        end
+          def instance_method_already_implemented?(method_name)
+            super || primary_key && ID_ATTRIBUTE_METHODS.include?(method_name)
+          end
 
-        # Defines the primary key field -- can be overridden in subclasses.
-        # Overwriting will negate any effect of the +primary_key_prefix_type+
-        # setting, though.
-        def primary_key
-          @primary_key = reset_primary_key unless defined? @primary_key
-          @primary_key
-        end
+          def dangerous_attribute_method?(method_name)
+            super && !ID_ATTRIBUTE_METHODS.include?(method_name)
+          end
 
-        # Returns a quoted version of the primary key name, used to construct
-        # SQL statements.
-        def quoted_primary_key
-          @quoted_primary_key ||= connection.quote_column_name(primary_key)
-        end
+          # Defines the primary key field -- can be overridden in subclasses.
+          # Overwriting will negate any effect of the +primary_key_prefix_type+
+          # setting, though.
+          def primary_key
+            @primary_key = reset_primary_key unless defined? @primary_key
+            @primary_key
+          end
 
-        def reset_primary_key #:nodoc:
-          if self == base_class
-            self.primary_key = get_primary_key(base_class.name)
-          else
-            self.primary_key = base_class.primary_key
+          # Returns a quoted version of the primary key name, used to construct
+          # SQL statements.
+          def quoted_primary_key
+            @quoted_primary_key ||= connection.quote_column_name(primary_key)
           end
-        end
 
-        def get_primary_key(base_name) #:nodoc:
-          if base_name && primary_key_prefix_type == :table_name
-            base_name.foreign_key(false)
-          elsif base_name && primary_key_prefix_type == :table_name_with_underscore
-            base_name.foreign_key
-          else
-            if ActiveRecord::Base != self && table_exists?
-              connection.schema_cache.primary_keys(table_name)
+          def reset_primary_key #:nodoc:
+            if self == base_class
+              self.primary_key = get_primary_key(base_class.name)
             else
-              'id'
+              self.primary_key = base_class.primary_key
             end
           end
-        end
 
-        # Sets the name of the primary key column.
-        #
-        #   class Project < ActiveRecord::Base
-        #     self.primary_key = 'sysid'
-        #   end
-        #
-        # You can also define the #primary_key method yourself:
-        #
-        #   class Project < ActiveRecord::Base
-        #     def self.primary_key
-        #       'foo_' + super
-        #     end
-        #   end
-        #
-        #   Project.primary_key # => "foo_id"
-        def primary_key=(value)
-          @primary_key        = value && value.to_s
-          @quoted_primary_key = nil
-          @attributes_builder = nil
+          def get_primary_key(base_name) #:nodoc:
+            if base_name && primary_key_prefix_type == :table_name
+              base_name.foreign_key(false)
+            elsif base_name && primary_key_prefix_type == :table_name_with_underscore
+              base_name.foreign_key
+            else
+              if ActiveRecord::Base != self && table_exists?
+                pk = connection.schema_cache.primary_keys(table_name)
+                suppress_composite_primary_key(pk)
+              else
+                "id"
+              end
+            end
+          end
+
+          # Sets the name of the primary key column.
+          #
+          #   class Project < ActiveRecord::Base
+          #     self.primary_key = 'sysid'
+          #   end
+          #
+          # You can also define the #primary_key method yourself:
+          #
+          #   class Project < ActiveRecord::Base
+          #     def self.primary_key
+          #       'foo_' + super
+          #     end
+          #   end
+          #
+          #   Project.primary_key # => "foo_id"
+          def primary_key=(value)
+            @primary_key        = value && value.to_s
+            @quoted_primary_key = nil
+            @attributes_builder = nil
+          end
+
+          private
+
+            def suppress_composite_primary_key(pk)
+              return pk unless pk.is_a?(Array)
+
+              warn <<-WARNING.strip_heredoc
+                WARNING: Active Record does not support composite primary key.
+
+                #{table_name} has composite primary key. Composite primary key is ignored.
+              WARNING
+            end
         end
-      end
     end
   end
 end
diff --git a/activerecord/lib/active_record/attribute_methods/query.rb b/activerecord/lib/active_record/attribute_methods/query.rb
index 10498f4322..6757e9b66a 100644
--- a/activerecord/lib/active_record/attribute_methods/query.rb
+++ b/activerecord/lib/active_record/attribute_methods/query.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActiveRecord
   module AttributeMethods
     module Query
diff --git a/activerecord/lib/active_record/attribute_methods/read.rb b/activerecord/lib/active_record/attribute_methods/read.rb
index ab2ecaa7c5..4077250583 100644
--- a/activerecord/lib/active_record/attribute_methods/read.rb
+++ b/activerecord/lib/active_record/attribute_methods/read.rb
@@ -1,55 +1,66 @@
+# frozen_string_literal: true
+
 module ActiveRecord
   module AttributeMethods
     module Read
       extend ActiveSupport::Concern
 
-      module ClassMethods
-        protected
+      module ClassMethods # :nodoc:
+        private
 
-        # We want to generate the methods via module_eval rather than
-        # define_method, because define_method is slower on dispatch.
-        # Evaluating many similar methods may use more memory as the instruction
-        # sequences are duplicated and cached (in MRI).  define_method may
-        # be slower on dispatch, but if you're careful about the closure
-        # created, then define_method will consume much less memory.
-        #
-        # But sometimes the database might return columns with
-        # characters that are not allowed in normal method names (like
-        # 'my_column(omg)'. So to work around this we first define with
-        # the __temp__ identifier, and then use alias method to rename
-        # it to what we want.
-        #
-        # We are also defining a constant to hold the frozen string of
-        # the attribute name. Using a constant means that we do not have
-        # to allocate an object on each call to the attribute method.
-        # Making it frozen means that it doesn't get duped when used to
-        # key the @attributes in read_attribute.
-        def define_method_attribute(name)
-          safe_name = name.unpack('h*'.freeze).first
-          temp_method = "__temp__#{safe_name}"
+          # We want to generate the methods via module_eval rather than
+          # define_method, because define_method is slower on dispatch.
+          # Evaluating many similar methods may use more memory as the instruction
+          # sequences are duplicated and cached (in MRI).  define_method may
+          # be slower on dispatch, but if you're careful about the closure
+          # created, then define_method will consume much less memory.
+          #
+          # But sometimes the database might return columns with
+          # characters that are not allowed in normal method names (like
+          # 'my_column(omg)'. So to work around this we first define with
+          # the __temp__ identifier, and then use alias method to rename
+          # it to what we want.
+          #
+          # We are also defining a constant to hold the frozen string of
+          # the attribute name. Using a constant means that we do not have
+          # to allocate an object on each call to the attribute method.
+          # Making it frozen means that it doesn't get duped when used to
+          # key the @attributes in read_attribute.
+          def define_method_attribute(name)
+            safe_name = name.unpack("h*".freeze).first
+            temp_method = "__temp__#{safe_name}"
 
-          ActiveRecord::AttributeMethods::AttrNames.set_name_cache safe_name, name
+            ActiveRecord::AttributeMethods::AttrNames.set_name_cache safe_name, name
+            sync_with_transaction_state = "sync_with_transaction_state" if name == primary_key
 
-          generated_attribute_methods.module_eval <<-STR, __FILE__, __LINE__ + 1
-            def #{temp_method}
-              name = ::ActiveRecord::AttributeMethods::AttrNames::ATTR_#{safe_name}
-              _read_attribute(name) { |n| missing_attribute(n, caller) }
-            end
-          STR
+            generated_attribute_methods.module_eval <<-STR, __FILE__, __LINE__ + 1
+              def #{temp_method}
+                #{sync_with_transaction_state}
+                name = ::ActiveRecord::AttributeMethods::AttrNames::ATTR_#{safe_name}
+                _read_attribute(name) { |n| missing_attribute(n, caller) }
+              end
+            STR
 
-          generated_attribute_methods.module_eval do
-            alias_method name, temp_method
-            undef_method temp_method
+            generated_attribute_methods.module_eval do
+              alias_method name, temp_method
+              undef_method temp_method
+            end
           end
-        end
       end
 
       # Returns the value of the attribute identified by <tt>attr_name</tt> after
       # it has been typecast (for example, "2004-12-12" in a date column is cast
       # to a date object, like Date.new(2004, 12, 12)).
       def read_attribute(attr_name, &block)
-        name = attr_name.to_s
-        name = self.class.primary_key if name == 'id'.freeze
+        name = if self.class.attribute_alias?(attr_name)
+          self.class.attribute_alias(attr_name).to_s
+        else
+          attr_name.to_s
+        end
+
+        primary_key = self.class.primary_key
+        name = primary_key if name == "id".freeze && primary_key
+        sync_with_transaction_state if name == primary_key
         _read_attribute(name, &block)
       end
 
@@ -69,7 +80,6 @@ module ActiveRecord
 
       alias :attribute :_read_attribute
       private :attribute
-
     end
   end
 end
diff --git a/activerecord/lib/active_record/attribute_methods/serialization.rb b/activerecord/lib/active_record/attribute_methods/serialization.rb
index 65978aea2a..ebc2baed34 100644
--- a/activerecord/lib/active_record/attribute_methods/serialization.rb
+++ b/activerecord/lib/active_record/attribute_methods/serialization.rb
@@ -1,8 +1,20 @@
+# frozen_string_literal: true
+
 module ActiveRecord
   module AttributeMethods
     module Serialization
       extend ActiveSupport::Concern
 
+      class ColumnNotSerializableError < StandardError
+        def initialize(name, type)
+          super <<-EOS.strip_heredoc
+            Column `#{name}` of type #{type.class} does not support `serialize` feature.
+            Usually it means that you are trying to use `serialize`
+            on a column that already implements serialization natively.
+          EOS
+        end
+      end
+
       module ClassMethods
         # If you have an attribute that needs to be saved to the database as an
         # object, and retrieved as the same object, then specify the name of that
@@ -26,7 +38,7 @@ module ActiveRecord
         # ==== Parameters
         #
         # * +attr_name+ - The field name that should be serialized.
-        # * +class_name_or_coder+ - Optional, a coder object, which responds to `.load` / `.dump`
+        # * +class_name_or_coder+ - Optional, a coder object, which responds to +.load+ and +.dump+
         #   or a class name that the object type should be equal to.
         #
         # ==== Example
@@ -50,17 +62,28 @@ module ActiveRecord
           # to ensure special objects (e.g. Active Record models) are dumped correctly
           # using the #as_json hook.
           coder = if class_name_or_coder == ::JSON
-                    Coders::JSON
-                  elsif [:load, :dump].all? { |x| class_name_or_coder.respond_to?(x) }
-                    class_name_or_coder
-                  else
-                    Coders::YAMLColumn.new(class_name_or_coder)
-                  end
+            Coders::JSON
+          elsif [:load, :dump].all? { |x| class_name_or_coder.respond_to?(x) }
+            class_name_or_coder
+          else
+            Coders::YAMLColumn.new(attr_name, class_name_or_coder)
+          end
 
           decorate_attribute_type(attr_name, :serialize) do |type|
+            if type_incompatible_with_serialize?(type, class_name_or_coder)
+              raise ColumnNotSerializableError.new(attr_name, type)
+            end
+
             Type::Serialized.new(type, coder)
           end
         end
+
+        private
+
+          def type_incompatible_with_serialize?(type, class_name)
+            type.is_a?(ActiveRecord::Type::Json) && class_name == ::JSON ||
+              type.respond_to?(:type_cast_array, true) && class_name == ::Array
+          end
       end
     end
   end
diff --git a/activerecord/lib/active_record/attribute_methods/time_zone_conversion.rb b/activerecord/lib/active_record/attribute_methods/time_zone_conversion.rb
index e160460286..d2b7817b45 100644
--- a/activerecord/lib/active_record/attribute_methods/time_zone_conversion.rb
+++ b/activerecord/lib/active_record/attribute_methods/time_zone_conversion.rb
@@ -1,4 +1,4 @@
-require 'active_support/core_ext/string/strip'
+# frozen_string_literal: true
 
 module ActiveRecord
   module AttributeMethods
@@ -26,90 +26,65 @@ module ActiveRecord
 
         private
 
-        def convert_time_to_time_zone(value)
-          return if value.nil?
+          def convert_time_to_time_zone(value)
+            return if value.nil?
 
-          if value.acts_like?(:time)
-            value.in_time_zone
-          elsif value.is_a?(::Float)
-            value
-          else
-            map_avoiding_infinite_recursion(value) { |v| convert_time_to_time_zone(v) }
+            if value.acts_like?(:time)
+              value.in_time_zone
+            elsif value.is_a?(::Float)
+              value
+            else
+              map_avoiding_infinite_recursion(value) { |v| convert_time_to_time_zone(v) }
+            end
           end
-        end
 
-        def set_time_zone_without_conversion(value)
-          ::Time.zone.local_to_utc(value).in_time_zone
-        end
+          def set_time_zone_without_conversion(value)
+            ::Time.zone.local_to_utc(value).try(:in_time_zone) if value
+          end
 
-        def map_avoiding_infinite_recursion(value)
-          map(value) do |v|
-            if value.equal?(v)
-              nil
-            else
-              yield(v)
+          def map_avoiding_infinite_recursion(value)
+            map(value) do |v|
+              if value.equal?(v)
+                nil
+              else
+                yield(v)
+              end
             end
           end
-        end
       end
 
       extend ActiveSupport::Concern
 
       included do
-        mattr_accessor :time_zone_aware_attributes, instance_writer: false
-        self.time_zone_aware_attributes = false
-
-        class_attribute :skip_time_zone_conversion_for_attributes, instance_writer: false
-        self.skip_time_zone_conversion_for_attributes = []
+        mattr_accessor :time_zone_aware_attributes, instance_writer: false, default: false
 
-        class_attribute :time_zone_aware_types, instance_writer: false
-        self.time_zone_aware_types = [:datetime, :not_explicitly_configured]
+        class_attribute :skip_time_zone_conversion_for_attributes, instance_writer: false, default: []
+        class_attribute :time_zone_aware_types, instance_writer: false, default: [ :datetime, :time ]
       end
 
-      module ClassMethods
+      module ClassMethods # :nodoc:
         private
 
-        def inherited(subclass)
-          # We need to apply this decorator here, rather than on module inclusion. The closure
-          # created by the matcher would otherwise evaluate for `ActiveRecord::Base`, not the
-          # sub class being decorated. As such, changes to `time_zone_aware_attributes`, or
-          # `skip_time_zone_conversion_for_attributes` would not be picked up.
-          subclass.class_eval do
-            matcher = ->(name, type) { create_time_zone_conversion_attribute?(name, type) }
-            decorate_matching_attribute_types(matcher, :_time_zone_conversion) do |type|
-              TimeZoneConverter.new(type)
+          def inherited(subclass)
+            super
+            # We need to apply this decorator here, rather than on module inclusion. The closure
+            # created by the matcher would otherwise evaluate for `ActiveRecord::Base`, not the
+            # sub class being decorated. As such, changes to `time_zone_aware_attributes`, or
+            # `skip_time_zone_conversion_for_attributes` would not be picked up.
+            subclass.class_eval do
+              matcher = ->(name, type) { create_time_zone_conversion_attribute?(name, type) }
+              decorate_matching_attribute_types(matcher, :_time_zone_conversion) do |type|
+                TimeZoneConverter.new(type)
+              end
             end
           end
-          super
-        end
-
-        def create_time_zone_conversion_attribute?(name, cast_type)
-          enabled_for_column = time_zone_aware_attributes &&
-            !self.skip_time_zone_conversion_for_attributes.include?(name.to_sym)
-          result = enabled_for_column &&
-            time_zone_aware_types.include?(cast_type.type)
-
-          if enabled_for_column &&
-            !result &&
-            cast_type.type == :time &&
-            time_zone_aware_types.include?(:not_explicitly_configured)
-            ActiveSupport::Deprecation.warn(<<-MESSAGE.strip_heredoc)
-              Time columns will become time zone aware in Rails 5.1. This
-              still causes `String`s to be parsed as if they were in `Time.zone`,
-              and `Time`s to be converted to `Time.zone`.
 
-              To keep the old behavior, you must add the following to your initializer:
+          def create_time_zone_conversion_attribute?(name, cast_type)
+            enabled_for_column = time_zone_aware_attributes &&
+              !skip_time_zone_conversion_for_attributes.include?(name.to_sym)
 
-                  config.active_record.time_zone_aware_types = [:datetime]
-
-              To silence this deprecation warning, add the following:
-
-                  config.active_record.time_zone_aware_types = [:datetime, :time]
-            MESSAGE
+            enabled_for_column && time_zone_aware_types.include?(cast_type.type)
           end
-
-          result
-        end
       end
     end
   end
diff --git a/activerecord/lib/active_record/attribute_methods/write.rb b/activerecord/lib/active_record/attribute_methods/write.rb
index 70c2d2f25d..bb0ec6a8c3 100644
--- a/activerecord/lib/active_record/attribute_methods/write.rb
+++ b/activerecord/lib/active_record/attribute_methods/write.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActiveRecord
   module AttributeMethods
     module Write
@@ -7,53 +9,60 @@ module ActiveRecord
         attribute_method_suffix "="
       end
 
-      module ClassMethods
-        protected
-
-        def define_method_attribute=(name)
-          safe_name = name.unpack('h*'.freeze).first
-          ActiveRecord::AttributeMethods::AttrNames.set_name_cache safe_name, name
-
-          generated_attribute_methods.module_eval <<-STR, __FILE__, __LINE__ + 1
-            def __temp__#{safe_name}=(value)
-              name = ::ActiveRecord::AttributeMethods::AttrNames::ATTR_#{safe_name}
-              write_attribute(name, value)
-            end
-            alias_method #{(name + '=').inspect}, :__temp__#{safe_name}=
-            undef_method :__temp__#{safe_name}=
-          STR
-        end
+      module ClassMethods # :nodoc:
+        private
+
+          def define_method_attribute=(name)
+            safe_name = name.unpack("h*".freeze).first
+            ActiveRecord::AttributeMethods::AttrNames.set_name_cache safe_name, name
+            sync_with_transaction_state = "sync_with_transaction_state" if name == primary_key
+
+            generated_attribute_methods.module_eval <<-STR, __FILE__, __LINE__ + 1
+              def __temp__#{safe_name}=(value)
+                name = ::ActiveRecord::AttributeMethods::AttrNames::ATTR_#{safe_name}
+                #{sync_with_transaction_state}
+                _write_attribute(name, value)
+              end
+              alias_method #{(name + '=').inspect}, :__temp__#{safe_name}=
+              undef_method :__temp__#{safe_name}=
+            STR
+          end
       end
 
       # Updates the attribute identified by <tt>attr_name</tt> with the
       # specified +value+. Empty strings for Integer and Float columns are
       # turned into +nil+.
       def write_attribute(attr_name, value)
-        write_attribute_with_type_cast(attr_name, value, true)
-      end
+        name = if self.class.attribute_alias?(attr_name)
+          self.class.attribute_alias(attr_name).to_s
+        else
+          attr_name.to_s
+        end
 
-      def raw_write_attribute(attr_name, value) # :nodoc:
-        write_attribute_with_type_cast(attr_name, value, false)
+        primary_key = self.class.primary_key
+        name = primary_key if name == "id".freeze && primary_key
+        sync_with_transaction_state if name == primary_key
+        _write_attribute(name, value)
       end
 
-      private
-      # Handle *= for method_missing.
-      def attribute=(attribute_name, value)
-        write_attribute(attribute_name, value)
+      # This method exists to avoid the expensive primary_key check internally, without
+      # breaking compatibility with the write_attribute API
+      def _write_attribute(attr_name, value) # :nodoc:
+        @attributes.write_from_user(attr_name.to_s, value)
+        value
       end
 
-      def write_attribute_with_type_cast(attr_name, value, should_type_cast)
-        attr_name = attr_name.to_s
-        attr_name = self.class.primary_key if attr_name == 'id' && self.class.primary_key
-
-        if should_type_cast
-          @attributes.write_from_user(attr_name, value)
-        else
-          @attributes.write_cast_value(attr_name, value)
+      private
+        def write_attribute_without_type_cast(attr_name, value)
+          name = attr_name.to_s
+          @attributes.write_cast_value(name, value)
+          value
         end
 
-        value
-      end
+        # Handle *= for method_missing.
+        def attribute=(attribute_name, value)
+          _write_attribute(attribute_name, value)
+        end
     end
   end
 end
diff --git a/activerecord/lib/active_record/attribute_mutation_tracker.rb b/activerecord/lib/active_record/attribute_mutation_tracker.rb
deleted file mode 100644
index 0133b4d0be..0000000000
--- a/activerecord/lib/active_record/attribute_mutation_tracker.rb
+++ /dev/null
@@ -1,70 +0,0 @@
-module ActiveRecord
-  class AttributeMutationTracker # :nodoc:
-    def initialize(attributes)
-      @attributes = attributes
-    end
-
-    def changed_values
-      attr_names.each_with_object({}.with_indifferent_access) do |attr_name, result|
-        if changed?(attr_name)
-          result[attr_name] = attributes[attr_name].original_value
-        end
-      end
-    end
-
-    def changes
-      attr_names.each_with_object({}.with_indifferent_access) do |attr_name, result|
-        if changed?(attr_name)
-          result[attr_name] = [attributes[attr_name].original_value, attributes.fetch_value(attr_name)]
-        end
-      end
-    end
-
-    def changed?(attr_name)
-      attr_name = attr_name.to_s
-      attributes[attr_name].changed?
-    end
-
-    def changed_in_place?(attr_name)
-      attributes[attr_name].changed_in_place?
-    end
-
-    def forget_change(attr_name)
-      attr_name = attr_name.to_s
-      attributes[attr_name] = attributes[attr_name].forgetting_assignment
-    end
-
-    protected
-
-    attr_reader :attributes
-
-    private
-
-    def attr_names
-      attributes.keys
-    end
-  end
-
-  class NullMutationTracker # :nodoc:
-    include Singleton
-
-    def changed_values
-      {}
-    end
-
-    def changes
-      {}
-    end
-
-    def changed?(*)
-      false
-    end
-
-    def changed_in_place?(*)
-      false
-    end
-
-    def forget_change(*)
-    end
-  end
-end
diff --git a/activerecord/lib/active_record/attributes.rb b/activerecord/lib/active_record/attributes.rb
index 519de271c3..35150889d9 100644
--- a/activerecord/lib/active_record/attributes.rb
+++ b/activerecord/lib/active_record/attributes.rb
@@ -1,4 +1,6 @@
-require 'active_record/attribute/user_provided_default'
+# frozen_string_literal: true
+
+require "active_model/attribute/user_provided_default"
 
 module ActiveRecord
   # See ActiveRecord::Attributes::ClassMethods for documentation
@@ -6,8 +8,7 @@ module ActiveRecord
     extend ActiveSupport::Concern
 
     included do
-      class_attribute :attributes_to_define_after_schema_loads, instance_accessor: false # :internal:
-      self.attributes_to_define_after_schema_loads = {}
+      class_attribute :attributes_to_define_after_schema_loads, instance_accessor: false, default: {} # :internal:
     end
 
     module ClassMethods
@@ -34,10 +35,10 @@ module ActiveRecord
       # is not passed, the previous default value (if any) will be used.
       # Otherwise, the default will be +nil+.
       #
-      # +array+ (PG only) specifies that the type should be an array (see the
+      # +array+ (PostgreSQL only) specifies that the type should be an array (see the
       # examples below).
       #
-      # +range+ (PG only) specifies that the type should be a range (see the
+      # +range+ (PostgreSQL only) specifies that the type should be a range (see the
       # examples below).
       #
       # ==== Examples
@@ -56,7 +57,7 @@ module ActiveRecord
       #   store_listing = StoreListing.new(price_in_cents: '10.1')
       #
       #   # before
-      #   store_listing.price_in_cents # => BigDecimal.new(10.1)
+      #   store_listing.price_in_cents # => BigDecimal(10.1)
       #
       #   class StoreListing < ActiveRecord::Base
       #     attribute :price_in_cents, :integer
@@ -116,7 +117,7 @@ module ActiveRecord
       # Users may also define their own custom types, as long as they respond
       # to the methods defined on the value type. The method +deserialize+ or
       # +cast+ will be called on your type object, with raw input from the
-      # database or from your controllers. See ActiveRecord::Type::Value for the
+      # database or from your controllers. See ActiveModel::Type::Value for the
       # expected API. It is recommended that your type objects inherit from an
       # existing type, or from ActiveRecord::Type::Value
       #
@@ -143,7 +144,7 @@ module ActiveRecord
       #   store_listing.price_in_cents # => 1000
       #
       # For more details on creating custom types, see the documentation for
-      # ActiveRecord::Type::Value. For more details on registering your types
+      # ActiveModel::Type::Value. For more details on registering your types
       # to be referenced by a symbol, see ActiveRecord::Type.register. You can
       # also pass a type object directly, in place of a symbol.
       #
@@ -190,8 +191,8 @@ module ActiveRecord
       # The type of an attribute is given the opportunity to change how dirty
       # tracking is performed. The methods +changed?+ and +changed_in_place?+
       # will be called from ActiveModel::Dirty. See the documentation for those
-      # methods in ActiveRecord::Type::Value for more details.
-      def attribute(name, cast_type, **options)
+      # methods in ActiveModel::Type::Value for more details.
+      def attribute(name, cast_type = Type::Value.new, **options)
         name = name.to_s
         reload_schema_from_cache
 
@@ -242,24 +243,24 @@ module ActiveRecord
 
       private
 
-      NO_DEFAULT_PROVIDED = Object.new # :nodoc:
-      private_constant :NO_DEFAULT_PROVIDED
+        NO_DEFAULT_PROVIDED = Object.new # :nodoc:
+        private_constant :NO_DEFAULT_PROVIDED
 
-      def define_default_attribute(name, value, type, from_user:)
-        if value == NO_DEFAULT_PROVIDED
-          default_attribute = _default_attributes[name].with_type(type)
-        elsif from_user
-          default_attribute = Attribute::UserProvidedDefault.new(
-            name,
-            value,
-            type,
-            _default_attributes[name],
-          )
-        else
-          default_attribute = Attribute.from_database(name, value, type)
+        def define_default_attribute(name, value, type, from_user:)
+          if value == NO_DEFAULT_PROVIDED
+            default_attribute = _default_attributes[name].with_type(type)
+          elsif from_user
+            default_attribute = ActiveModel::Attribute::UserProvidedDefault.new(
+              name,
+              value,
+              type,
+              _default_attributes.fetch(name.to_s) { nil },
+            )
+          else
+            default_attribute = ActiveModel::Attribute.from_database(name, value, type)
+          end
+          _default_attributes[name] = default_attribute
         end
-        _default_attributes[name] = default_attribute
-      end
     end
   end
 end
diff --git a/activerecord/lib/active_record/autosave_association.rb b/activerecord/lib/active_record/autosave_association.rb
index 06c7482bf9..a1250c3835 100644
--- a/activerecord/lib/active_record/autosave_association.rb
+++ b/activerecord/lib/active_record/autosave_association.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActiveRecord
   # = Active Record Autosave Association
   #
@@ -140,8 +142,7 @@ module ActiveRecord
 
     included do
       Associations::Builder::Association.extensions << AssociationBuilderExtension
-      mattr_accessor :index_nested_attribute_errors, instance_writer: false
-      self.index_nested_attribute_errors = false
+      mattr_accessor :index_nested_attribute_errors, instance_writer: false, default: false
     end
 
     module ClassMethods # :nodoc:
@@ -154,10 +155,10 @@ module ActiveRecord
             # Loop prevention for validation of associations
             unless @_already_called[name]
               begin
-                @_already_called[name]=true
+                @_already_called[name] = true
                 result = instance_eval(&block)
               ensure
-                @_already_called[name]=false
+                @_already_called[name] = false
               end
             end
 
@@ -181,6 +182,7 @@ module ActiveRecord
 
           if reflection.collection?
             before_save :before_save_collection_association
+            after_save :after_save_collection_association
 
             define_non_cyclic_method(save_method) { save_collection_association(reflection) }
             # Doesn't use after_save as that would save associations added in after_create/after_update twice
@@ -215,13 +217,7 @@ module ActiveRecord
               method = :validate_single_association
             end
 
-            define_non_cyclic_method(validation_method) do
-              send(method, reflection)
-              # TODO: remove the following line as soon as the return value of
-              # callbacks is ignored, that is, returning `false` does not
-              # display a deprecation warning or halts the callback chain.
-              true
-            end
+            define_non_cyclic_method(validation_method) { send(method, reflection) }
             validate validation_method
             after_validation :_ensure_no_duplicate_errors
           end
@@ -267,7 +263,7 @@ module ActiveRecord
     # Returns whether or not this record has been changed in any way (including whether
     # any of its nested autosave associations are likewise changed)
     def changed_for_autosave?
-      new_record? || changed? || marked_for_destruction? || nested_records_changed_for_autosave?
+      new_record? || has_changes_to_save? || marked_for_destruction? || nested_records_changed_for_autosave?
     end
 
     private
@@ -325,30 +321,24 @@ module ActiveRecord
       # Returns whether or not the association is valid and applies any errors to
       # the parent, <tt>self</tt>, if it wasn't. Skips any <tt>:autosave</tt>
       # enabled records if they're marked_for_destruction? or destroyed.
-      def association_valid?(reflection, record, index=nil)
+      def association_valid?(reflection, record, index = nil)
         return true if record.destroyed? || (reflection.options[:autosave] && record.marked_for_destruction?)
 
-        validation_context = self.validation_context unless [:create, :update].include?(self.validation_context)
-        unless valid = record.valid?(validation_context)
+        context = validation_context unless [:create, :update].include?(validation_context)
+
+        unless valid = record.valid?(context)
           if reflection.options[:autosave]
             indexed_attribute = !index.nil? && (reflection.options[:index_errors] || ActiveRecord::Base.index_nested_attribute_errors)
 
             record.errors.each do |attribute, message|
-              if indexed_attribute
-                attribute = "#{reflection.name}[#{index}].#{attribute}"
-              else
-                attribute = "#{reflection.name}.#{attribute}"
-              end
+              attribute = normalize_reflection_attribute(indexed_attribute, reflection, index, attribute)
               errors[attribute] << message
               errors[attribute].uniq!
             end
 
             record.errors.details.each_key do |attribute|
-              if indexed_attribute
-                reflection_attribute = "#{reflection.name}[#{index}].#{attribute}"
-              else
-                reflection_attribute = "#{reflection.name}.#{attribute}"
-              end
+              reflection_attribute =
+                normalize_reflection_attribute(indexed_attribute, reflection, index, attribute).to_sym
 
               record.errors.details[attribute].each do |error|
                 errors.details[reflection_attribute] << error
@@ -362,11 +352,22 @@ module ActiveRecord
         valid
       end
 
+      def normalize_reflection_attribute(indexed_attribute, reflection, index, attribute)
+        if indexed_attribute
+          "#{reflection.name}[#{index}].#{attribute}"
+        else
+          "#{reflection.name}.#{attribute}"
+        end
+      end
+
       # Is used as a before_save callback to check while saving a collection
       # association whether or not the parent was a new record before saving.
       def before_save_collection_association
         @new_record_before_save = new_record?
-        true
+      end
+
+      def after_save_collection_association
+        @new_record_before_save = false
       end
 
       # Saves any new associated records, or all loaded autosave associations if
@@ -381,6 +382,9 @@ module ActiveRecord
         if association = association_instance_get(reflection.name)
           autosave = reflection.options[:autosave]
 
+          # reconstruct the scope now that we know the owner's id
+          association.reset_scope
+
           if records = associated_records_to_validate_or_save(association, @new_record_before_save, autosave)
             if autosave
               records_to_destroy = records.select(&:marked_for_destruction?)
@@ -400,15 +404,12 @@ module ActiveRecord
                   association.insert_record(record) unless reflection.nested?
                 end
               elsif autosave
-                saved = record.save(:validate => false)
+                saved = record.save(validate: false)
               end
 
               raise ActiveRecord::Rollback unless saved
             end
           end
-
-          # reconstruct the scope now that we know the owner's id
-          association.reset_scope if association.respond_to?(:reset_scope)
         end
       end
 
@@ -435,9 +436,12 @@ module ActiveRecord
             if (autosave && record.changed_for_autosave?) || new_record? || record_changed?(reflection, record, key)
               unless reflection.through_reflection
                 record[reflection.foreign_key] = key
+                if inverse_reflection = reflection.inverse_of
+                  record.association(inverse_reflection.name).loaded!
+                end
               end
 
-              saved = record.save(:validate => !autosave)
+              saved = record.save(validate: !autosave)
               raise ActiveRecord::Rollback if !saved && autosave
               saved
             end
@@ -449,7 +453,7 @@ module ActiveRecord
       def record_changed?(reflection, record, key)
         record.new_record? ||
           (record.has_attribute?(reflection.foreign_key) && record[reflection.foreign_key] != key) ||
-          record.attribute_changed?(reflection.foreign_key)
+          record.will_save_change_to_attribute?(reflection.foreign_key)
       end
 
       # Saves the associated record if it's new or <tt>:autosave</tt> is enabled.
@@ -457,7 +461,9 @@ module ActiveRecord
       # In addition, it will destroy the association if it was marked for destruction.
       def save_belongs_to_association(reflection)
         association = association_instance_get(reflection.name)
-        record      = association && association.load_target
+        return unless association && association.loaded? && !association.stale_target?
+
+        record = association.load_target
         if record && !record.destroyed?
           autosave = reflection.options[:autosave]
 
@@ -465,7 +471,7 @@ module ActiveRecord
             self[reflection.foreign_key] = nil
             record.destroy
           elsif autosave != false
-            saved = record.save(:validate => !autosave) if record.new_record? || (autosave && record.changed_for_autosave?)
+            saved = record.save(validate: !autosave) if record.new_record? || (autosave && record.changed_for_autosave?)
 
             if association.updated?
               association_id = record.send(reflection.options[:primary_key] || :id)
diff --git a/activerecord/lib/active_record/base.rb b/activerecord/lib/active_record/base.rb
index 6a1a27ce41..b7ad944cec 100644
--- a/activerecord/lib/active_record/base.rb
+++ b/activerecord/lib/active_record/base.rb
@@ -1,25 +1,28 @@
-require 'yaml'
-require 'active_support/benchmarkable'
-require 'active_support/dependencies'
-require 'active_support/descendants_tracker'
-require 'active_support/time'
-require 'active_support/core_ext/module/attribute_accessors'
-require 'active_support/core_ext/array/extract_options'
-require 'active_support/core_ext/hash/deep_merge'
-require 'active_support/core_ext/hash/slice'
-require 'active_support/core_ext/hash/transform_values'
-require 'active_support/core_ext/string/behavior'
-require 'active_support/core_ext/kernel/singleton_class'
-require 'active_support/core_ext/module/introspection'
-require 'active_support/core_ext/object/duplicable'
-require 'active_support/core_ext/class/subclasses'
-require 'active_record/attribute_decorators'
-require 'active_record/errors'
-require 'active_record/log_subscriber'
-require 'active_record/explain_subscriber'
-require 'active_record/relation/delegation'
-require 'active_record/attributes'
-require 'active_record/type_caster'
+# frozen_string_literal: true
+
+require "yaml"
+require "active_support/benchmarkable"
+require "active_support/dependencies"
+require "active_support/descendants_tracker"
+require "active_support/time"
+require "active_support/core_ext/module/attribute_accessors"
+require "active_support/core_ext/array/extract_options"
+require "active_support/core_ext/hash/deep_merge"
+require "active_support/core_ext/hash/slice"
+require "active_support/core_ext/hash/transform_values"
+require "active_support/core_ext/string/behavior"
+require "active_support/core_ext/kernel/singleton_class"
+require "active_support/core_ext/module/introspection"
+require "active_support/core_ext/object/duplicable"
+require "active_support/core_ext/class/subclasses"
+require "active_record/attribute_decorators"
+require "active_record/define_callbacks"
+require "active_record/errors"
+require "active_record/log_subscriber"
+require "active_record/explain_subscriber"
+require "active_record/relation/delegation"
+require "active_record/attributes"
+require "active_record/type_caster"
 
 module ActiveRecord #:nodoc:
   # = Active Record
@@ -303,6 +306,7 @@ module ActiveRecord #:nodoc:
     include AttributeDecorators
     include Locking::Optimistic
     include Locking::Pessimistic
+    include DefineCallbacks
     include AttributeMethods
     include Callbacks
     include Timestamp
@@ -312,8 +316,8 @@ module ActiveRecord #:nodoc:
     include NestedAttributes
     include Aggregations
     include Transactions
-    include NoTouching
     include TouchLater
+    include NoTouching
     include Reflection
     include Serialization
     include Store
diff --git a/activerecord/lib/active_record/callbacks.rb b/activerecord/lib/active_record/callbacks.rb
index 95de6937af..9dbdf845bd 100644
--- a/activerecord/lib/active_record/callbacks.rb
+++ b/activerecord/lib/active_record/callbacks.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActiveRecord
   # = Active Record \Callbacks
   #
@@ -96,9 +98,9 @@ module ActiveRecord
   # == Types of callbacks
   #
   # There are four types of callbacks accepted by the callback macros: Method references (symbol), callback objects,
-  # inline methods (using a proc), and inline eval methods (using a string). Method references and callback objects
+  # inline methods (using a proc). Method references and callback objects
   # are the recommended approaches, inline methods using a proc are sometimes appropriate (such as for
-  # creating mix-ins), and inline eval methods are deprecated.
+  # creating mix-ins).
   #
   # The method reference callbacks work by specifying a protected or private method available in the object, like this:
   #
@@ -225,6 +227,55 @@ module ActiveRecord
   #
   # This way, the +before_destroy+ gets executed before the <tt>dependent: :destroy</tt> is called, and the data is still available.
   #
+  # Also, there are cases when you want several callbacks of the same type to
+  # be executed in order.
+  #
+  # For example:
+  #
+  #   class Topic < ActiveRecord::Base
+  #     has_many :children
+  #
+  #     after_save :log_children
+  #     after_save :do_something_else
+  #
+  #     private
+  #
+  #     def log_children
+  #       # Child processing
+  #     end
+  #
+  #     def do_something_else
+  #       # Something else
+  #     end
+  #   end
+  #
+  # In this case the +log_children+ gets executed before +do_something_else+.
+  # The same applies to all non-transactional callbacks.
+  #
+  # In case there are multiple transactional callbacks as seen below, the order
+  # is reversed.
+  #
+  # For example:
+  #
+  #   class Topic < ActiveRecord::Base
+  #     has_many :children
+  #
+  #     after_commit :log_children
+  #     after_commit :do_something_else
+  #
+  #     private
+  #
+  #     def log_children
+  #       # Child processing
+  #     end
+  #
+  #     def do_something_else
+  #       # Something else
+  #     end
+  #   end
+  #
+  # In this case the +do_something_else+ gets executed before +log_children+.
+  #
   # == \Transactions
   #
   # The entire callback chain of a {#save}[rdoc-ref:Persistence#save], {#save!}[rdoc-ref:Persistence#save!],
@@ -265,17 +316,6 @@ module ActiveRecord
       :before_destroy, :around_destroy, :after_destroy, :after_commit, :after_rollback
     ]
 
-    module ClassMethods # :nodoc:
-      include ActiveModel::Callbacks
-    end
-
-    included do
-      include ActiveModel::Validations::Callbacks
-
-      define_model_callbacks :initialize, :find, :touch, :only => :after
-      define_model_callbacks :save, :create, :update, :destroy
-    end
-
     def destroy #:nodoc:
       @_destroy_callback_already_called ||= false
       return if @_destroy_callback_already_called
@@ -294,15 +334,15 @@ module ActiveRecord
 
   private
 
-    def create_or_update(*) #:nodoc:
+    def create_or_update(*)
       _run_save_callbacks { super }
     end
 
-    def _create_record #:nodoc:
+    def _create_record
       _run_create_callbacks { super }
     end
 
-    def _update_record(*) #:nodoc:
+    def _update_record(*)
       _run_update_callbacks { super }
     end
   end
diff --git a/activerecord/lib/active_record/coders/json.rb b/activerecord/lib/active_record/coders/json.rb
index cb185a881e..a69b38487e 100644
--- a/activerecord/lib/active_record/coders/json.rb
+++ b/activerecord/lib/active_record/coders/json.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActiveRecord
   module Coders # :nodoc:
     class JSON # :nodoc:
diff --git a/activerecord/lib/active_record/coders/yaml_column.rb b/activerecord/lib/active_record/coders/yaml_column.rb
index 2456b8ad8c..11559141c7 100644
--- a/activerecord/lib/active_record/coders/yaml_column.rb
+++ b/activerecord/lib/active_record/coders/yaml_column.rb
@@ -1,12 +1,14 @@
-require 'yaml'
+# frozen_string_literal: true
+
+require "yaml"
 
 module ActiveRecord
   module Coders # :nodoc:
     class YAMLColumn # :nodoc:
-
       attr_accessor :object_class
 
-      def initialize(object_class = Object)
+      def initialize(attr_name, object_class = Object)
+        @attr_name = attr_name
         @object_class = object_class
         check_arity_of_constructor
       end
@@ -14,37 +16,35 @@ module ActiveRecord
       def dump(obj)
         return if obj.nil?
 
-        assert_valid_value(obj)
+        assert_valid_value(obj, action: "dump")
         YAML.dump obj
       end
 
       def load(yaml)
         return object_class.new if object_class != Object && yaml.nil?
-        return yaml unless yaml.is_a?(String) && yaml =~ /^---/
+        return yaml unless yaml.is_a?(String) && /^---/.match?(yaml)
         obj = YAML.load(yaml)
 
-        assert_valid_value(obj)
+        assert_valid_value(obj, action: "load")
         obj ||= object_class.new if object_class != Object
 
         obj
       end
 
-      def assert_valid_value(obj)
+      def assert_valid_value(obj, action:)
         unless obj.nil? || obj.is_a?(object_class)
           raise SerializationTypeMismatch,
-            "Attribute was supposed to be a #{object_class}, but was a #{obj.class}. -- #{obj.inspect}"
+            "can't #{action} `#{@attr_name}`: was supposed to be a #{object_class}, but was a #{obj.class}. -- #{obj.inspect}"
         end
       end
 
       private
 
-      def check_arity_of_constructor
-        begin
+        def check_arity_of_constructor
           load(nil)
         rescue ArgumentError
           raise ArgumentError, "Cannot serialize #{object_class}. Classes passed to `serialize` must have a 0 argument constructor."
         end
-      end
     end
   end
 end
diff --git a/activerecord/lib/active_record/collection_cache_key.rb b/activerecord/lib/active_record/collection_cache_key.rb
index 8d41c0d799..0520591f4f 100644
--- a/activerecord/lib/active_record/collection_cache_key.rb
+++ b/activerecord/lib/active_record/collection_cache_key.rb
@@ -1,24 +1,37 @@
+# frozen_string_literal: true
+
 module ActiveRecord
   module CollectionCacheKey
-
     def collection_cache_key(collection = all, timestamp_column = :updated_at) # :nodoc:
-      query_signature = Digest::MD5.hexdigest(collection.to_sql)
+      query_signature = ActiveSupport::Digest.hexdigest(collection.to_sql)
       key = "#{collection.model_name.cache_key}/query-#{query_signature}"
 
-      if collection.loaded?
-        size = collection.size
+      if collection.loaded? || collection.distinct_value
+        size = collection.records.size
         if size > 0
-          timestamp = collection.max_by(&timestamp_column).public_send(timestamp_column)
+          timestamp = collection.max_by(&timestamp_column)._read_attribute(timestamp_column)
         end
       else
+        if collection.eager_loading?
+          collection = collection.send(:apply_join_dependency)
+        end
         column_type = type_for_attribute(timestamp_column.to_s)
-        column = "#{connection.quote_table_name(collection.table_name)}.#{connection.quote_column_name(timestamp_column)}"
+        column = connection.column_name_from_arel_node(collection.arel_attribute(timestamp_column))
+        select_values = "COUNT(*) AS #{connection.quote_column_name("size")}, MAX(%s) AS timestamp"
+
+        if collection.has_limit_or_offset?
+          query = collection.select(column)
+          subquery_alias = "subquery_for_cache_key"
+          subquery_column = "#{subquery_alias}.#{timestamp_column}"
+          subquery = query.arel.as(subquery_alias)
+          arel = Arel::SelectManager.new(subquery).project(select_values % subquery_column)
+        else
+          query = collection.unscope(:order)
+          query.select_values = [select_values % column]
+          arel = query.arel
+        end
 
-        query = collection
-          .unscope(:select)
-          .select("COUNT(*) AS #{connection.quote_column_name("size")}", "MAX(#{column}) AS timestamp")
-          .unscope(:order)
-        result = connection.select_one(query)
+        result = connection.select_one(arel, nil)
 
         if result.blank?
           size = 0
diff --git a/activerecord/lib/active_record/connection_adapters/abstract/connection_pool.rb b/activerecord/lib/active_record/connection_adapters/abstract/connection_pool.rb
index eb5a742f2d..c730584902 100644
--- a/activerecord/lib/active_record/connection_adapters/abstract/connection_pool.rb
+++ b/activerecord/lib/active_record/connection_adapters/abstract/connection_pool.rb
@@ -1,6 +1,8 @@
-require 'thread'
-require 'concurrent/map'
-require 'monitor'
+# frozen_string_literal: true
+
+require "thread"
+require "concurrent/map"
+require "monitor"
 
 module ActiveRecord
   # Raised when a connection could not be obtained within the connection
@@ -61,30 +63,25 @@ module ActiveRecord
     # There are several connection-pooling-related options that you can add to
     # your database connection configuration:
     #
-    # * +pool+: number indicating size of connection pool (default 5)
-    # * +checkout_timeout+: number of seconds to block and wait for a connection
-    #   before giving up and raising a timeout error (default 5 seconds).
-    # * +reaping_frequency+: frequency in seconds to periodically run the
-    #   Reaper, which attempts to find and recover connections from dead
-    #   threads, which can occur if a programmer forgets to close a
-    #   connection at the end of a thread or a thread dies unexpectedly.
-    #   Regardless of this setting, the Reaper will be invoked before every
-    #   blocking wait. (Default nil, which means don't schedule the Reaper).
+    # * +pool+: maximum number of connections the pool may manage (default 5).
+    # * +idle_timeout+: number of seconds that a connection will be kept
+    #   unused in the pool before it is automatically disconnected (default
+    #   300 seconds). Set this to zero to keep connections forever.
+    # * +checkout_timeout+: number of seconds to wait for a connection to
+    #   become available before giving up and raising a timeout error (default
+    #   5 seconds).
     #
     #--
     # Synchronization policy:
     # * all public methods can be called outside +synchronize+
-    # * access to these i-vars needs to be in +synchronize+:
+    # * access to these instance variables needs to be in +synchronize+:
     #   * @connections
     #   * @now_connecting
     # * private methods that require being called in a +synchronize+ blocks
     #   are now explicitly documented
     class ConnectionPool
-      # Threadsafe, fair, FIFO queue.  Meant to be used by ConnectionPool
-      # with which it shares a Monitor.  But could be a generic Queue.
-      #
-      # The Queue in stdlib's 'thread' could replace this class except
-      # stdlib's doesn't support waiting with a timeout.
+      # Threadsafe, fair, LIFO queue.  Meant to be used by ConnectionPool
+      # with which it shares a Monitor.
       class Queue
         def initialize(lock = Monitor.new)
           @lock = lock
@@ -116,7 +113,7 @@ module ActiveRecord
           end
         end
 
-        # If +element+ is in the queue, remove and return it, or nil.
+        # If +element+ is in the queue, remove and return it, or +nil+.
         def delete(element)
           synchronize do
             @queue.delete(element)
@@ -135,7 +132,7 @@ module ActiveRecord
         # If +timeout+ is not given, remove and return the head the
         # queue if the number of available elements is strictly
         # greater than the number of threads currently waiting (that
-        # is, don't jump ahead in line).  Otherwise, return nil.
+        # is, don't jump ahead in line).  Otherwise, return +nil+.
         #
         # If +timeout+ is given, block if there is no element
         # available, waiting up to +timeout+ seconds for an element to
@@ -150,61 +147,61 @@ module ActiveRecord
 
         private
 
-        def internal_poll(timeout)
-          no_wait_poll || (timeout && wait_poll(timeout))
-        end
+          def internal_poll(timeout)
+            no_wait_poll || (timeout && wait_poll(timeout))
+          end
 
-        def synchronize(&block)
-          @lock.synchronize(&block)
-        end
+          def synchronize(&block)
+            @lock.synchronize(&block)
+          end
 
-        # Test if the queue currently contains any elements.
-        def any?
-          !@queue.empty?
-        end
+          # Test if the queue currently contains any elements.
+          def any?
+            !@queue.empty?
+          end
 
-        # A thread can remove an element from the queue without
-        # waiting if and only if the number of currently available
-        # connections is strictly greater than the number of waiting
-        # threads.
-        def can_remove_no_wait?
-          @queue.size > @num_waiting
-        end
+          # A thread can remove an element from the queue without
+          # waiting if and only if the number of currently available
+          # connections is strictly greater than the number of waiting
+          # threads.
+          def can_remove_no_wait?
+            @queue.size > @num_waiting
+          end
 
-        # Removes and returns the head of the queue if possible, or nil.
-        def remove
-          @queue.shift
-        end
+          # Removes and returns the head of the queue if possible, or +nil+.
+          def remove
+            @queue.pop
+          end
 
-        # Remove and return the head the queue if the number of
-        # available elements is strictly greater than the number of
-        # threads currently waiting.  Otherwise, return nil.
-        def no_wait_poll
-          remove if can_remove_no_wait?
-        end
+          # Remove and return the head the queue if the number of
+          # available elements is strictly greater than the number of
+          # threads currently waiting.  Otherwise, return +nil+.
+          def no_wait_poll
+            remove if can_remove_no_wait?
+          end
 
-        # Waits on the queue up to +timeout+ seconds, then removes and
-        # returns the head of the queue.
-        def wait_poll(timeout)
-          @num_waiting += 1
+          # Waits on the queue up to +timeout+ seconds, then removes and
+          # returns the head of the queue.
+          def wait_poll(timeout)
+            @num_waiting += 1
 
-          t0 = Time.now
-          elapsed = 0
-          loop do
-            @cond.wait(timeout - elapsed)
+            t0 = Time.now
+            elapsed = 0
+            loop do
+              @cond.wait(timeout - elapsed)
 
-            return remove if any?
+              return remove if any?
 
-            elapsed = Time.now - t0
-            if elapsed >= timeout
-              msg = 'could not obtain a connection from the pool within %0.3f seconds (waited %0.3f seconds); all pooled connections were in use' %
-                [timeout, elapsed]
-              raise ConnectionTimeoutError, msg
+              elapsed = Time.now - t0
+              if elapsed >= timeout
+                msg = "could not obtain a connection from the pool within %0.3f seconds (waited %0.3f seconds); all pooled connections were in use" %
+                  [timeout, elapsed]
+                raise ConnectionTimeoutError, msg
+              end
             end
+          ensure
+            @num_waiting -= 1
           end
-        ensure
-          @num_waiting -= 1
-        end
       end
 
       # Adds the ability to turn a basic fair FIFO queue into one
@@ -268,25 +265,25 @@ module ActiveRecord
       # Connections must be leased while holding the main pool mutex. This is
       # an internal subclass that also +.leases+ returned connections while
       # still in queue's critical section (queue synchronizes with the same
-      # +@lock+ as the main pool) so that a returned connection is already
+      # <tt>@lock</tt> as the main pool) so that a returned connection is already
       # leased and there is no need to re-enter synchronized block.
       class ConnectionLeasingQueue < Queue # :nodoc:
         include BiasableQueue
 
         private
-        def internal_poll(timeout)
-          conn = super
-          conn.lease if conn
-          conn
-        end
+          def internal_poll(timeout)
+            conn = super
+            conn.lease if conn
+            conn
+          end
       end
 
-      # Every +frequency+ seconds, the reaper will call +reap+ on +pool+.
-      # A reaper instantiated with a nil frequency will never reap the
-      # connection pool.
+      # Every +frequency+ seconds, the reaper will call +reap+ and +flush+ on
+      # +pool+. A reaper instantiated with a zero frequency will never reap
+      # the connection pool.
       #
-      # Configure the frequency by setting "reaping_frequency" in your
-      # database yaml file.
+      # Configure the frequency by setting +reaping_frequency+ in your database
+      # yaml file (default 60 seconds).
       class Reaper
         attr_reader :pool, :frequency
 
@@ -296,17 +293,19 @@ module ActiveRecord
         end
 
         def run
-          return unless frequency
+          return unless frequency && frequency > 0
           Thread.new(frequency, pool) { |t, p|
             loop do
               sleep t
               p.reap
+              p.flush
             end
           }
         end
       end
 
       include MonitorMixin
+      include QueryCache::ConnectionPoolConfiguration
 
       attr_accessor :automatic_reconnect, :checkout_timeout, :schema_cache
       attr_reader :spec, :connections, :size, :reaper
@@ -323,23 +322,25 @@ module ActiveRecord
         @spec = spec
 
         @checkout_timeout = (spec.config[:checkout_timeout] && spec.config[:checkout_timeout].to_f) || 5
-        @reaper = Reaper.new(self, (spec.config[:reaping_frequency] && spec.config[:reaping_frequency].to_f))
-        @reaper.run
+        if @idle_timeout = spec.config.fetch(:idle_timeout, 300)
+          @idle_timeout = @idle_timeout.to_f
+          @idle_timeout = nil if @idle_timeout <= 0
+        end
 
         # default max pool size to 5
         @size = (spec.config[:pool] && spec.config[:pool].to_i) || 5
 
-        # The cache of threads mapped to reserved connections, the sole purpose
-        # of the cache is to speed-up +connection+ method, it is not the authoritative
-        # registry of which thread owns which connection, that is tracked by
-        # +connection.owner+ attr on each +connection+ instance.
+        # This variable tracks the cache of threads mapped to reserved connections, with the
+        # sole purpose of speeding up the +connection+ method. It is not the authoritative
+        # registry of which thread owns which connection. Connection ownership is tracked by
+        # the +connection.owner+ attr on each +connection+ instance.
         # The invariant works like this: if there is mapping of <tt>thread => conn</tt>,
-        # then that +thread+ does indeed own that +conn+, however an absence of a such
-        # mapping does not mean that the +thread+ doesn't own the said connection, in
+        # then that +thread+ does indeed own that +conn+. However, an absence of a such
+        # mapping does not mean that the +thread+ doesn't own the said connection. In
         # that case +conn.owner+ attr should be consulted.
-        # Access and modification of +@thread_cached_conns+ does not require
+        # Access and modification of <tt>@thread_cached_conns</tt> does not require
         # synchronization.
-        @thread_cached_conns = Concurrent::Map.new(:initial_capacity => @size)
+        @thread_cached_conns = Concurrent::Map.new(initial_capacity: @size)
 
         @connections         = []
         @automatic_reconnect = true
@@ -349,10 +350,25 @@ module ActiveRecord
         # currently in the process of independently establishing connections to the DB.
         @now_connecting = 0
 
-        # A boolean toggle that allows/disallows new connections.
-        @new_cons_enabled = true
+        @threads_blocking_new_connections = 0
 
         @available = ConnectionLeasingQueue.new self
+
+        @lock_thread = false
+
+        # +reaping_frequency+ is configurable mostly for historical reasons, but it could
+        # also be useful if someone wants a very low +idle_timeout+.
+        reaping_frequency = spec.config.fetch(:reaping_frequency, 60)
+        @reaper = Reaper.new(self, reaping_frequency && reaping_frequency.to_f)
+        @reaper.run
+      end
+
+      def lock_thread=(lock_thread)
+        if lock_thread
+          @lock_thread = Thread.current
+        else
+          @lock_thread = nil
+        end
       end
 
       # Retrieve the connection associated with the current thread, or call
@@ -361,13 +377,13 @@ module ActiveRecord
       # #connection can be called any number of times; the connection is
       # held in a cache keyed by a thread.
       def connection
-        @thread_cached_conns[connection_cache_key(Thread.current)] ||= checkout
+        @thread_cached_conns[connection_cache_key(@lock_thread || Thread.current)] ||= checkout
       end
 
-      # Is there an open connection that is being used for the current thread?
+      # Returns true if there is an open connection being used for the current thread.
       #
       # This method only works for connections that have been obtained through
-      # #connection or #with_connection methods, connections obtained through
+      # #connection or #with_connection methods. Connections obtained through
       # #checkout will not be detected by #active_connection?
       def active_connection?
         @thread_cached_conns[connection_cache_key(Thread.current)]
@@ -415,7 +431,10 @@ module ActiveRecord
         with_exclusively_acquired_all_connections(raise_on_acquisition_timeout) do
           synchronize do
             @connections.each do |conn|
-              checkin conn
+              if conn.in_use?
+                conn.steal!
+                checkin conn
+              end
               conn.disconnect!
             end
             @connections = []
@@ -426,14 +445,29 @@ module ActiveRecord
 
       # Disconnects all connections in the pool, and clears the pool.
       #
-      # The pool first tries to gain ownership of all connections, if unable to
+      # The pool first tries to gain ownership of all connections. If unable to
       # do so within a timeout interval (default duration is
-      # <tt>spec.config[:checkout_timeout] * 2</tt> seconds), the pool is forcefully
+      # <tt>spec.config[:checkout_timeout] * 2</tt> seconds), then the pool is forcefully
       # disconnected without any regard for other connection owning threads.
       def disconnect!
         disconnect(false)
       end
 
+      # Discards all connections in the pool (even if they're currently
+      # leased!), along with the pool itself. Any further interaction with the
+      # pool (except #spec and #schema_cache) is undefined.
+      #
+      # See AbstractAdapter#discard!
+      def discard! # :nodoc:
+        synchronize do
+          return if @connections.nil? # already discarded
+          @connections.each do |conn|
+            conn.discard!
+          end
+          @connections = @available = @thread_cached_conns = nil
+        end
+      end
+
       # Clears the cache which maps classes and re-connects connections that
       # require reloading.
       #
@@ -442,41 +476,27 @@ module ActiveRecord
       #   connections in the pool within a timeout interval (default duration is
       #   <tt>spec.config[:checkout_timeout] * 2</tt> seconds).
       def clear_reloadable_connections(raise_on_acquisition_timeout = true)
-        num_new_conns_required = 0
-
         with_exclusively_acquired_all_connections(raise_on_acquisition_timeout) do
           synchronize do
             @connections.each do |conn|
-              checkin conn
+              if conn.in_use?
+                conn.steal!
+                checkin conn
+              end
               conn.disconnect! if conn.requires_reloading?
             end
             @connections.delete_if(&:requires_reloading?)
-
             @available.clear
-
-            if @connections.size < @size
-              # because of the pruning done by this method, we might be running
-              # low on connections, while threads stuck in queue are helpless
-              # (not being able to establish new connections for themselves),
-              # see also more detailed explanation in +remove+
-              num_new_conns_required = num_waiting_in_queue - @connections.size
-            end
-
-            @connections.each do |conn|
-              @available.add conn
-            end
           end
         end
-
-        bulk_make_new_connections(num_new_conns_required) if num_new_conns_required > 0
       end
 
       # Clears the cache which maps classes and re-connects connections that
       # require reloading.
       #
-      # The pool first tries to gain ownership of all connections, if unable to
+      # The pool first tries to gain ownership of all connections. If unable to
       # do so within a timeout interval (default duration is
-      # <tt>spec.config[:checkout_timeout] * 2</tt> seconds), the pool forcefully
+      # <tt>spec.config[:checkout_timeout] * 2</tt> seconds), then the pool forcefully
       # clears the cache and reloads connections without any regard for other
       # connection owning threads.
       def clear_reloadable_connections!
@@ -507,14 +527,16 @@ module ActiveRecord
       # +conn+: an AbstractAdapter object, which was obtained by earlier by
       # calling #checkout on this pool.
       def checkin(conn)
-        synchronize do
-          remove_connection_from_thread_cache conn
+        conn.lock.synchronize do
+          synchronize do
+            remove_connection_from_thread_cache conn
 
-          conn._run_checkin_callbacks do
-            conn.expire
-          end
+            conn._run_checkin_callbacks do
+              conn.expire
+            end
 
-          @available.add conn
+            @available.add conn
+          end
         end
       end
 
@@ -530,20 +552,20 @@ module ActiveRecord
           @available.delete conn
 
           # @available.any_waiting? => true means that prior to removing this
-          # conn, the pool was at its max size (@connections.size == @size)
-          # this would mean that any threads stuck waiting in the queue wouldn't
+          # conn, the pool was at its max size (@connections.size == @size).
+          # This would mean that any threads stuck waiting in the queue wouldn't
           # know they could checkout_new_connection, so let's do it for them.
           # Because condition-wait loop is encapsulated in the Queue class
           # (that in turn is oblivious to ConnectionPool implementation), threads
-          # that are "stuck" there are helpless, they have no way of creating
+          # that are "stuck" there are helpless. They have no way of creating
           # new connections and are completely reliant on us feeding available
           # connections into the Queue.
           needs_new_connection = @available.any_waiting?
         end
 
         # This is intentionally done outside of the synchronized section as we
-        # would like not to hold the main mutex while checking out new connections,
-        # thus there is some chance that needs_new_connection information is now
+        # would like not to hold the main mutex while checking out new connections.
+        # Thus there is some chance that needs_new_connection information is now
         # stale, we can live with that (bulk_make_new_connections will make
         # sure not to exceed the pool's @size limit).
         bulk_make_new_connections(1) if needs_new_connection
@@ -556,225 +578,291 @@ module ActiveRecord
         stale_connections = synchronize do
           @connections.select do |conn|
             conn.in_use? && !conn.owner.alive?
+          end.each do |conn|
+            conn.steal!
           end
         end
 
         stale_connections.each do |conn|
-          synchronize do
-            if conn.active?
-              conn.reset!
-              checkin conn
-            else
-              remove conn
-            end
+          if conn.active?
+            conn.reset!
+            checkin conn
+          else
+            remove conn
           end
         end
       end
 
+      # Disconnect all connections that have been idle for at least
+      # +minimum_idle+ seconds. Connections currently checked out, or that were
+      # checked in less than +minimum_idle+ seconds ago, are unaffected.
+      def flush(minimum_idle = @idle_timeout)
+        return if minimum_idle.nil?
+
+        idle_connections = synchronize do
+          @connections.select do |conn|
+            !conn.in_use? && conn.seconds_idle >= minimum_idle
+          end.each do |conn|
+            conn.lease
+
+            @available.delete conn
+            @connections.delete conn
+          end
+        end
+
+        idle_connections.each do |conn|
+          conn.disconnect!
+        end
+      end
+
+      # Disconnect all currently idle connections. Connections currently checked
+      # out are unaffected.
+      def flush!
+        reap
+        flush(-1)
+      end
+
       def num_waiting_in_queue # :nodoc:
         @available.num_waiting
       end
 
-      private
-      #--
-      # this is unfortunately not concurrent
-      def bulk_make_new_connections(num_new_conns_needed)
-        num_new_conns_needed.times do
-          # try_to_checkout_new_connection will not exceed pool's @size limit
-          if new_conn = try_to_checkout_new_connection
-            # make the new_conn available to the starving threads stuck @available Queue
-            checkin(new_conn)
-          end
-        end
-      end
-
-      #--
-      # From the discussion on GitHub:
-      #  https://github.com/rails/rails/pull/14938#commitcomment-6601951
-      # This hook-in method allows for easier monkey-patching fixes needed by
-      # JRuby users that use Fibers.
-      def connection_cache_key(thread)
-        thread
-      end
-
-      # Take control of all existing connections so a "group" action such as
-      # reload/disconnect can be performed safely. It is no longer enough to
-      # wrap it in +synchronize+ because some pool's actions are allowed
-      # to be performed outside of the main +synchronize+ block.
-      def with_exclusively_acquired_all_connections(raise_on_acquisition_timeout = true)
-        with_new_connections_blocked do
-          attempt_to_checkout_all_existing_connections(raise_on_acquisition_timeout)
-          yield
+      # Return connection pool's usage statistic
+      # Example:
+      #
+      #    ActiveRecord::Base.connection_pool.stat # => { size: 15, connections: 1, busy: 1, dead: 0, idle: 0, waiting: 0, checkout_timeout: 5 }
+      def stat
+        synchronize do
+          {
+            size: size,
+            connections: @connections.size,
+            busy: @connections.count { |c| c.in_use? && c.owner.alive? },
+            dead: @connections.count { |c| c.in_use? && !c.owner.alive? },
+            idle: @connections.count { |c| !c.in_use? },
+            waiting: num_waiting_in_queue,
+            checkout_timeout: checkout_timeout
+          }
         end
       end
 
-      def attempt_to_checkout_all_existing_connections(raise_on_acquisition_timeout = true)
-        collected_conns = synchronize do
-          # account for our own connections
-          @connections.select {|conn| conn.owner == Thread.current}
+      private
+        #--
+        # this is unfortunately not concurrent
+        def bulk_make_new_connections(num_new_conns_needed)
+          num_new_conns_needed.times do
+            # try_to_checkout_new_connection will not exceed pool's @size limit
+            if new_conn = try_to_checkout_new_connection
+              # make the new_conn available to the starving threads stuck @available Queue
+              checkin(new_conn)
+            end
+          end
         end
 
-        newly_checked_out = []
-        timeout_time      = Time.now + (@checkout_timeout * 2)
+        #--
+        # From the discussion on GitHub:
+        #  https://github.com/rails/rails/pull/14938#commitcomment-6601951
+        # This hook-in method allows for easier monkey-patching fixes needed by
+        # JRuby users that use Fibers.
+        def connection_cache_key(thread)
+          thread
+        end
 
-        @available.with_a_bias_for(Thread.current) do
-          loop do
-            synchronize do
-              return if collected_conns.size == @connections.size && @now_connecting == 0
-              remaining_timeout = timeout_time - Time.now
-              remaining_timeout = 0 if remaining_timeout < 0
-              conn = checkout_for_exclusive_access(remaining_timeout)
-              collected_conns   << conn
-              newly_checked_out << conn
-            end
+        # Take control of all existing connections so a "group" action such as
+        # reload/disconnect can be performed safely. It is no longer enough to
+        # wrap it in +synchronize+ because some pool's actions are allowed
+        # to be performed outside of the main +synchronize+ block.
+        def with_exclusively_acquired_all_connections(raise_on_acquisition_timeout = true)
+          with_new_connections_blocked do
+            attempt_to_checkout_all_existing_connections(raise_on_acquisition_timeout)
+            yield
           end
         end
-      rescue ExclusiveConnectionTimeoutError
-        # <tt>raise_on_acquisition_timeout == false</tt> means we are directed to ignore any
-        # timeouts and are expected to just give up: we've obtained as many connections
-        # as possible, note that in a case like that we don't return any of the
-        # +newly_checked_out+ connections.
 
-        if raise_on_acquisition_timeout
+        def attempt_to_checkout_all_existing_connections(raise_on_acquisition_timeout = true)
+          collected_conns = synchronize do
+            # account for our own connections
+            @connections.select { |conn| conn.owner == Thread.current }
+          end
+
+          newly_checked_out = []
+          timeout_time      = Time.now + (@checkout_timeout * 2)
+
+          @available.with_a_bias_for(Thread.current) do
+            loop do
+              synchronize do
+                return if collected_conns.size == @connections.size && @now_connecting == 0
+                remaining_timeout = timeout_time - Time.now
+                remaining_timeout = 0 if remaining_timeout < 0
+                conn = checkout_for_exclusive_access(remaining_timeout)
+                collected_conns   << conn
+                newly_checked_out << conn
+              end
+            end
+          end
+        rescue ExclusiveConnectionTimeoutError
+          # <tt>raise_on_acquisition_timeout == false</tt> means we are directed to ignore any
+          # timeouts and are expected to just give up: we've obtained as many connections
+          # as possible, note that in a case like that we don't return any of the
+          # +newly_checked_out+ connections.
+
+          if raise_on_acquisition_timeout
+            release_newly_checked_out = true
+            raise
+          end
+        rescue Exception # if something else went wrong
+          # this can't be a "naked" rescue, because we have should return conns
+          # even for non-StandardErrors
           release_newly_checked_out = true
           raise
+        ensure
+          if release_newly_checked_out && newly_checked_out
+            # releasing only those conns that were checked out in this method, conns
+            # checked outside this method (before it was called) are not for us to release
+            newly_checked_out.each { |conn| checkin(conn) }
+          end
         end
-      rescue Exception # if something else went wrong
-        # this can't be a "naked" rescue, because we have should return conns
-        # even for non-StandardErrors
-        release_newly_checked_out = true
-        raise
-      ensure
-        if release_newly_checked_out && newly_checked_out
-          # releasing only those conns that were checked out in this method, conns
-          # checked outside this method (before it was called) are not for us to release
-          newly_checked_out.each {|conn| checkin(conn)}
-        end
-      end
-
-      #--
-      # Must be called in a synchronize block.
-      def checkout_for_exclusive_access(checkout_timeout)
-        checkout(checkout_timeout)
-      rescue ConnectionTimeoutError
-        # this block can't be easily moved into attempt_to_checkout_all_existing_connections's
-        # rescue block, because doing so would put it outside of synchronize section, without
-        # being in a critical section thread_report might become inaccurate
-        msg = "could not obtain ownership of all database connections in #{checkout_timeout} seconds"
 
-        thread_report = []
-        @connections.each do |conn|
-          unless conn.owner == Thread.current
-            thread_report << "#{conn} is owned by #{conn.owner}"
+        #--
+        # Must be called in a synchronize block.
+        def checkout_for_exclusive_access(checkout_timeout)
+          checkout(checkout_timeout)
+        rescue ConnectionTimeoutError
+          # this block can't be easily moved into attempt_to_checkout_all_existing_connections's
+          # rescue block, because doing so would put it outside of synchronize section, without
+          # being in a critical section thread_report might become inaccurate
+          msg = "could not obtain ownership of all database connections in #{checkout_timeout} seconds".dup
+
+          thread_report = []
+          @connections.each do |conn|
+            unless conn.owner == Thread.current
+              thread_report << "#{conn} is owned by #{conn.owner}"
+            end
           end
+
+          msg << " (#{thread_report.join(', ')})" if thread_report.any?
+
+          raise ExclusiveConnectionTimeoutError, msg
         end
 
-        msg << " (#{thread_report.join(', ')})" if thread_report.any?
+        def with_new_connections_blocked
+          synchronize do
+            @threads_blocking_new_connections += 1
+          end
 
-        raise ExclusiveConnectionTimeoutError, msg
-      end
+          yield
+        ensure
+          num_new_conns_required = 0
 
-      def with_new_connections_blocked
-        previous_value = nil
-        synchronize do
-          previous_value, @new_cons_enabled = @new_cons_enabled, false
-        end
-        yield
-      ensure
-        synchronize { @new_cons_enabled = previous_value }
-      end
+          synchronize do
+            @threads_blocking_new_connections -= 1
 
-      # Acquire a connection by one of 1) immediately removing one
-      # from the queue of available connections, 2) creating a new
-      # connection if the pool is not at capacity, 3) waiting on the
-      # queue for a connection to become available.
-      #
-      # Raises:
-      # - ActiveRecord::ConnectionTimeoutError if a connection could not be acquired
-      #
-      #--
-      # Implementation detail: the connection returned by +acquire_connection+
-      # will already be "+connection.lease+ -ed" to the current thread.
-      def acquire_connection(checkout_timeout)
-        # NOTE: we rely on +@available.poll+ and +try_to_checkout_new_connection+ to
-        # +conn.lease+ the returned connection (and to do this in a +synchronized+
-        # section), this is not the cleanest implementation, as ideally we would
-        # <tt>synchronize { conn.lease }</tt> in this method, but by leaving it to +@available.poll+
-        # and +try_to_checkout_new_connection+ we can piggyback on +synchronize+ sections
-        # of the said methods and avoid an additional +synchronize+ overhead.
-        if conn = @available.poll || try_to_checkout_new_connection
-          conn
-        else
-          reap
-          @available.poll(checkout_timeout)
+            if @threads_blocking_new_connections.zero?
+              @available.clear
+
+              num_new_conns_required = num_waiting_in_queue
+
+              @connections.each do |conn|
+                next if conn.in_use?
+
+                @available.add conn
+                num_new_conns_required -= 1
+              end
+            end
+          end
+
+          bulk_make_new_connections(num_new_conns_required) if num_new_conns_required > 0
         end
-      end
 
-      #--
-      # if owner_thread param is omitted, this must be called in synchronize block
-      def remove_connection_from_thread_cache(conn, owner_thread = conn.owner)
-        @thread_cached_conns.delete_pair(connection_cache_key(owner_thread), conn)
-      end
-      alias_method :release, :remove_connection_from_thread_cache
+        # Acquire a connection by one of 1) immediately removing one
+        # from the queue of available connections, 2) creating a new
+        # connection if the pool is not at capacity, 3) waiting on the
+        # queue for a connection to become available.
+        #
+        # Raises:
+        # - ActiveRecord::ConnectionTimeoutError if a connection could not be acquired
+        #
+        #--
+        # Implementation detail: the connection returned by +acquire_connection+
+        # will already be "+connection.lease+ -ed" to the current thread.
+        def acquire_connection(checkout_timeout)
+          # NOTE: we rely on <tt>@available.poll</tt> and +try_to_checkout_new_connection+ to
+          # +conn.lease+ the returned connection (and to do this in a +synchronized+
+          # section). This is not the cleanest implementation, as ideally we would
+          # <tt>synchronize { conn.lease }</tt> in this method, but by leaving it to <tt>@available.poll</tt>
+          # and +try_to_checkout_new_connection+ we can piggyback on +synchronize+ sections
+          # of the said methods and avoid an additional +synchronize+ overhead.
+          if conn = @available.poll || try_to_checkout_new_connection
+            conn
+          else
+            reap
+            @available.poll(checkout_timeout)
+          end
+        end
 
-      def new_connection
-        Base.send(spec.adapter_method, spec.config).tap do |conn|
-          conn.schema_cache = schema_cache.dup if schema_cache
+        #--
+        # if owner_thread param is omitted, this must be called in synchronize block
+        def remove_connection_from_thread_cache(conn, owner_thread = conn.owner)
+          @thread_cached_conns.delete_pair(connection_cache_key(owner_thread), conn)
         end
-      end
+        alias_method :release, :remove_connection_from_thread_cache
 
-      # If the pool is not at a +@size+ limit, establish new connection. Connecting
-      # to the DB is done outside main synchronized section.
-      #--
-      # Implementation constraint: a newly established connection returned by this
-      # method must be in the +.leased+ state.
-      def try_to_checkout_new_connection
-        # first in synchronized section check if establishing new conns is allowed
-        # and increment @now_connecting, to prevent overstepping this pool's @size
-        # constraint
-        do_checkout = synchronize do
-          if @new_cons_enabled && (@connections.size + @now_connecting) < @size
-            @now_connecting += 1
+        def new_connection
+          Base.send(spec.adapter_method, spec.config).tap do |conn|
+            conn.schema_cache = schema_cache.dup if schema_cache
           end
         end
-        if do_checkout
-          begin
-            # if successfully incremented @now_connecting establish new connection
-            # outside of synchronized section
-            conn = checkout_new_connection
-          ensure
-            synchronize do
-              if conn
-                adopt_connection(conn)
-                # returned conn needs to be already leased
-                conn.lease
+
+        # If the pool is not at a <tt>@size</tt> limit, establish new connection. Connecting
+        # to the DB is done outside main synchronized section.
+        #--
+        # Implementation constraint: a newly established connection returned by this
+        # method must be in the +.leased+ state.
+        def try_to_checkout_new_connection
+          # first in synchronized section check if establishing new conns is allowed
+          # and increment @now_connecting, to prevent overstepping this pool's @size
+          # constraint
+          do_checkout = synchronize do
+            if @threads_blocking_new_connections.zero? && (@connections.size + @now_connecting) < @size
+              @now_connecting += 1
+            end
+          end
+          if do_checkout
+            begin
+              # if successfully incremented @now_connecting establish new connection
+              # outside of synchronized section
+              conn = checkout_new_connection
+            ensure
+              synchronize do
+                if conn
+                  adopt_connection(conn)
+                  # returned conn needs to be already leased
+                  conn.lease
+                end
+                @now_connecting -= 1
               end
-              @now_connecting -= 1
             end
           end
         end
-      end
 
-      def adopt_connection(conn)
-        conn.pool = self
-        @connections << conn
-      end
+        def adopt_connection(conn)
+          conn.pool = self
+          @connections << conn
+        end
 
-      def checkout_new_connection
-        raise ConnectionNotEstablished unless @automatic_reconnect
-        new_connection
-      end
+        def checkout_new_connection
+          raise ConnectionNotEstablished unless @automatic_reconnect
+          new_connection
+        end
 
-      def checkout_and_verify(c)
-        c._run_checkout_callbacks do
-          c.verify!
+        def checkout_and_verify(c)
+          c._run_checkout_callbacks do
+            c.verify!
+          end
+          c
+        rescue
+          remove c
+          c.disconnect!
+          raise
         end
-        c
-      rescue
-        remove c
-        c.disconnect!
-        raise
-      end
     end
 
     # ConnectionHandler is a collection of ConnectionPool objects. It is used
@@ -789,7 +877,7 @@ module ActiveRecord
     #   end
     #
     #   class Book < ActiveRecord::Base
-    #     establish_connection "library_db"
+    #     establish_connection :library_db
     #   end
     #
     #   class ScaryBook < Book
@@ -821,15 +909,35 @@ module ActiveRecord
     # All Active Record models use this handler to determine the connection pool that they
     # should use.
     #
-    # The ConnectionHandler class is not coupled with the Active models, as it has no knowlodge
-    # about the model. The model, needs to pass a specification name to the handler,
-    # in order to lookup the correct connection pool.
+    # The ConnectionHandler class is not coupled with the Active models, as it has no knowledge
+    # about the model. The model needs to pass a specification name to the handler,
+    # in order to look up the correct connection pool.
     class ConnectionHandler
+      def self.unowned_pool_finalizer(pid_map) # :nodoc:
+        lambda do |_|
+          discard_unowned_pools(pid_map)
+        end
+      end
+
+      def self.discard_unowned_pools(pid_map) # :nodoc:
+        pid_map.each do |pid, pools|
+          pools.values.compact.each(&:discard!) unless pid == Process.pid
+        end
+      end
+
       def initialize
         # These caches are keyed by spec.name (ConnectionSpecification#name).
-        @owner_to_pool = Concurrent::Map.new(:initial_capacity => 2) do |h,k|
-          h[k] = Concurrent::Map.new(:initial_capacity => 2)
+        @owner_to_pool = Concurrent::Map.new(initial_capacity: 2) do |h, k|
+          # Discard the parent's connection pools immediately; we have no need
+          # of them
+          ConnectionHandler.discard_unowned_pools(h)
+
+          h[k] = Concurrent::Map.new(initial_capacity: 2)
         end
+
+        # Backup finalizer: if the forked child never needed a pool, the above
+        # early discard has not occurred
+        ObjectSpace.define_finalizer self, ConnectionHandler.unowned_pool_finalizer(@owner_to_pool)
       end
 
       def connection_pool_list
@@ -842,7 +950,21 @@ module ActiveRecord
         spec = resolver.spec(config)
 
         remove_connection(spec.name)
-        owner_to_pool[spec.name] = ConnectionAdapters::ConnectionPool.new(spec)
+
+        message_bus = ActiveSupport::Notifications.instrumenter
+        payload = {
+          connection_id: object_id
+        }
+        if spec
+          payload[:spec_name] = spec.name
+          payload[:config] = spec.config
+        end
+
+        message_bus.instrument("!connection.active_record", payload) do
+          owner_to_pool[spec.name] = ConnectionAdapters::ConnectionPool.new(spec)
+        end
+
+        owner_to_pool[spec.name]
       end
 
       # Returns true if there are any active connections among the connection
@@ -869,13 +991,20 @@ module ActiveRecord
         connection_pool_list.each(&:disconnect!)
       end
 
+      # Disconnects all currently idle connections.
+      #
+      # See ConnectionPool#flush! for details.
+      def flush_idle_connections!
+        connection_pool_list.each(&:flush!)
+      end
+
       # Locate the connection of the nearest super class. This can be an
       # active or defined connection: if it is the latter, it will be
       # opened and set as the active connection for the class it was defined
       # for (not necessarily the current class).
       def retrieve_connection(spec_name) #:nodoc:
         pool = retrieve_connection_pool(spec_name)
-        raise ConnectionNotEstablished, "No connection pool with id '#{spec_name}' found." unless pool
+        raise ConnectionNotEstablished, "No connection pool with '#{spec_name}' found." unless pool
         pool.connection
       end
 
@@ -888,7 +1017,7 @@ module ActiveRecord
 
       # Remove the connection for this class. This will close the active
       # connection and the defined connection (if they exist). The result
-      # can be used as an argument for establish_connection, for easily
+      # can be used as an argument for #establish_connection, for easily
       # re-establishing the connection.
       def remove_connection(spec_name)
         if pool = owner_to_pool.delete(spec_name)
@@ -920,14 +1049,14 @@ module ActiveRecord
 
       private
 
-      def owner_to_pool
-        @owner_to_pool[Process.pid]
-      end
+        def owner_to_pool
+          @owner_to_pool[Process.pid]
+        end
 
-      def pool_from_any_process_for(spec_name)
-        owner_to_pool = @owner_to_pool.values.find { |v| v[spec_name] }
-        owner_to_pool && owner_to_pool[spec_name]
-      end
+        def pool_from_any_process_for(spec_name)
+          owner_to_pool = @owner_to_pool.values.reverse.find { |v| v[spec_name] }
+          owner_to_pool && owner_to_pool[spec_name]
+        end
     end
   end
 end
diff --git a/activerecord/lib/active_record/connection_adapters/abstract/database_limits.rb b/activerecord/lib/active_record/connection_adapters/abstract/database_limits.rb
index 6711049588..7a9e7add24 100644
--- a/activerecord/lib/active_record/connection_adapters/abstract/database_limits.rb
+++ b/activerecord/lib/active_record/connection_adapters/abstract/database_limits.rb
@@ -1,7 +1,8 @@
+# frozen_string_literal: true
+
 module ActiveRecord
   module ConnectionAdapters # :nodoc:
     module DatabaseLimits
-
       # Returns the maximum length of a table alias.
       def table_alias_length
         255
@@ -47,7 +48,7 @@ module ActiveRecord
       end
 
       # Returns the maximum number of elements in an IN (x,y,z) clause.
-      # nil means no limit.
+      # +nil+ means no limit.
       def in_clause_length
         nil
       end
@@ -61,7 +62,6 @@ module ActiveRecord
       def joins_per_query
         256
       end
-
     end
   end
 end
diff --git a/activerecord/lib/active_record/connection_adapters/abstract/database_statements.rb b/activerecord/lib/active_record/connection_adapters/abstract/database_statements.rb
index 507a925d32..36048bee03 100644
--- a/activerecord/lib/active_record/connection_adapters/abstract/database_statements.rb
+++ b/activerecord/lib/active_record/connection_adapters/abstract/database_statements.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActiveRecord
   module ConnectionAdapters # :nodoc:
     module DatabaseStatements
@@ -7,29 +9,43 @@ module ActiveRecord
       end
 
       # Converts an arel AST to SQL
-      def to_sql(arel, binds = [])
-        if arel.respond_to?(:ast)
-          collected = visitor.accept(arel.ast, collector)
-          collected.compile(binds.dup, self)
+      def to_sql(arel_or_sql_string, binds = [])
+        sql, _ = to_sql_and_binds(arel_or_sql_string, binds)
+        sql
+      end
+
+      def to_sql_and_binds(arel_or_sql_string, binds = []) # :nodoc:
+        if arel_or_sql_string.respond_to?(:ast)
+          unless binds.empty?
+            raise "Passing bind parameters with an arel AST is forbidden. " \
+              "The values must be stored on the AST directly"
+          end
+          sql, binds = visitor.accept(arel_or_sql_string.ast, collector).value
+          [sql.freeze, binds || []]
         else
-          arel
+          [arel_or_sql_string.dup.freeze, binds]
         end
       end
+      private :to_sql_and_binds
 
       # This is used in the StatementCache object. It returns an object that
       # can be used to query the database repeatedly.
-      def cacheable_query(arel) # :nodoc:
+      def cacheable_query(klass, arel) # :nodoc:
         if prepared_statements
-          ActiveRecord::StatementCache.query visitor, arel.ast
+          sql, binds = visitor.accept(arel.ast, collector).value
+          query = klass.query(sql)
         else
-          ActiveRecord::StatementCache.partial_query visitor, arel.ast, collector
+          collector = PartialQueryCollector.new
+          parts, binds = visitor.accept(arel.ast, collector).value
+          query = klass.partial_query(parts)
         end
+        [query, binds]
       end
 
       # Returns an ActiveRecord::Result instance.
       def select_all(arel, name = nil, binds = [], preparable: nil)
-        arel, binds = binds_from_relation arel, binds
-        sql = to_sql(arel, binds)
+        arel = arel_from_relation(arel)
+        sql, binds = to_sql_and_binds(arel, binds)
         if !prepared_statements || (arel.is_a?(String) && preparable.nil?)
           preparable = false
         else
@@ -50,23 +66,31 @@ module ActiveRecord
 
       # Returns a single value from a record
       def select_value(arel, name = nil, binds = [])
-        arel, binds = binds_from_relation arel, binds
-        if result = select_rows(to_sql(arel, binds), name, binds).first
-          result.first
-        end
+        single_value_from_rows(select_rows(arel, name, binds))
       end
 
       # Returns an array of the values of the first column in a select:
       #   select_values("SELECT id FROM companies LIMIT 3") => [1,2,3]
       def select_values(arel, name = nil, binds = [])
-        arel, binds = binds_from_relation arel, binds
-        select_rows(to_sql(arel, binds), name, binds).map(&:first)
+        select_rows(arel, name, binds).map(&:first)
       end
 
       # Returns an array of arrays containing the field values.
       # Order is the same as that returned by +columns+.
-      def select_rows(sql, name = nil, binds = [])
-        exec_query(sql, name, binds).rows
+      def select_rows(arel, name = nil, binds = [])
+        select_all(arel, name, binds).rows
+      end
+
+      def query_value(sql, name = nil) # :nodoc:
+        single_value_from_rows(query(sql, name))
+      end
+
+      def query_values(sql, name = nil) # :nodoc:
+        query(sql, name).map(&:first)
+      end
+
+      def query(sql, name = nil) # :nodoc:
+        exec_query(sql, name).rows
       end
 
       # Executes the SQL statement in the context of this connection and returns
@@ -81,21 +105,22 @@ module ActiveRecord
       # Executes +sql+ statement in the context of this connection using
       # +binds+ as the bind substitutes. +name+ is logged along with
       # the executed +sql+ statement.
-      def exec_query(sql, name = 'SQL', binds = [], prepare: false)
+      def exec_query(sql, name = "SQL", binds = [], prepare: false)
         raise NotImplementedError
       end
 
       # Executes insert +sql+ statement in the context of this connection using
       # +binds+ as the bind substitutes. +name+ is logged along with
       # the executed +sql+ statement.
-      def exec_insert(sql, name, binds, pk = nil, sequence_name = nil)
+      def exec_insert(sql, name = nil, binds = [], pk = nil, sequence_name = nil)
+        sql, binds = sql_for_insert(sql, pk, nil, sequence_name, binds)
         exec_query(sql, name, binds)
       end
 
       # Executes delete +sql+ statement in the context of this connection using
       # +binds+ as the bind substitutes. +name+ is logged along with
       # the executed +sql+ statement.
-      def exec_delete(sql, name, binds)
+      def exec_delete(sql, name = nil, binds = [])
         exec_query(sql, name, binds)
       end
 
@@ -107,46 +132,43 @@ module ActiveRecord
       # Executes update +sql+ statement in the context of this connection using
       # +binds+ as the bind substitutes. +name+ is logged along with
       # the executed +sql+ statement.
-      def exec_update(sql, name, binds)
+      def exec_update(sql, name = nil, binds = [])
         exec_query(sql, name, binds)
       end
 
       # Executes an INSERT query and returns the new record's ID
       #
-      # +id_value+ will be returned unless the value is nil, in
+      # +id_value+ will be returned unless the value is +nil+, in
       # which case the database will attempt to calculate the last inserted
       # id and return that value.
       #
       # If the next id was calculated in advance (as in Oracle), it should be
       # passed in as +id_value+.
       def insert(arel, name = nil, pk = nil, id_value = nil, sequence_name = nil, binds = [])
-        sql, binds, pk, sequence_name = sql_for_insert(to_sql(arel, binds), pk, id_value, sequence_name, binds)
+        sql, binds = to_sql_and_binds(arel, binds)
         value = exec_insert(sql, name, binds, pk, sequence_name)
         id_value || last_inserted_id(value)
       end
       alias create insert
-      alias insert_sql insert
-      deprecate insert_sql: :insert
 
       # Executes the update statement and returns the number of rows affected.
       def update(arel, name = nil, binds = [])
-        exec_update(to_sql(arel, binds), name, binds)
+        sql, binds = to_sql_and_binds(arel, binds)
+        exec_update(sql, name, binds)
       end
-      alias update_sql update
-      deprecate update_sql: :update
 
       # Executes the delete statement and returns the number of rows affected.
       def delete(arel, name = nil, binds = [])
-        exec_delete(to_sql(arel, binds), name, binds)
+        sql, binds = to_sql_and_binds(arel, binds)
+        exec_delete(sql, name, binds)
       end
-      alias delete_sql delete
-      deprecate delete_sql: :delete
 
       # Returns +true+ when the connection adapter supports prepared statement
       # caching, otherwise returns +false+
-      def supports_statement_cache?
-        false
+      def supports_statement_cache? # :nodoc:
+        true
       end
+      deprecate :supports_statement_cache?
 
       # Runs the given block in a database transaction, and returns the result
       # of the block.
@@ -159,7 +181,7 @@ module ActiveRecord
       #
       # In order to get around this problem, #transaction will emulate the effect
       # of nested transactions, by using savepoints:
-      # http://dev.mysql.com/doc/refman/5.7/en/savepoint.html
+      # https://dev.mysql.com/doc/refman/5.7/en/savepoint.html
       # Savepoints are supported by MySQL and PostgreSQL. SQLite3 version >= '3.6.8'
       # supports savepoints.
       #
@@ -211,7 +233,7 @@ module ActiveRecord
       # You should consult the documentation for your database to understand the
       # semantics of these different levels:
       #
-      # * http://www.postgresql.org/docs/current/static/transaction-iso.html
+      # * https://www.postgresql.org/docs/current/static/transaction-iso.html
       # * https://dev.mysql.com/doc/refman/5.7/en/set-transaction.html
       #
       # An ActiveRecord::TransactionIsolationError will be raised if:
@@ -244,7 +266,7 @@ module ActiveRecord
       end
 
       def reset_transaction #:nodoc:
-        @transaction_manager = TransactionManager.new(self)
+        @transaction_manager = ConnectionAdapters::TransactionManager.new(self)
       end
 
       # Register a record with the current transaction so that its after_commit and after_rollback callbacks
@@ -302,6 +324,9 @@ module ActiveRecord
 
       # Inserts the given fixture into the table. Overridden in adapters that require
       # something beyond a simple insert (eg. Oracle).
+      # Most of adapters should implement `insert_fixtures` that leverages bulk SQL insert.
+      # We keep this method to provide fallback
+      # for databases like sqlite that do not support bulk inserts.
       def insert_fixture(fixture, table_name)
         fixture = fixture.stringify_keys
 
@@ -314,16 +339,52 @@ module ActiveRecord
             raise Fixture::FixtureError, %(table "#{table_name}" has no column named #{name.inspect}.)
           end
         end
-        key_list = fixture.keys.map { |name| quote_column_name(name) }
-        value_list = prepare_binds_for_database(binds).map do |value|
-          begin
-            quote(value)
-          rescue TypeError
-            quote(YAML.dump(value))
+
+        table = Arel::Table.new(table_name)
+
+        values = binds.map do |bind|
+          value = with_yaml_fallback(bind.value_for_database)
+          [table[bind.name], value]
+        end
+
+        manager = Arel::InsertManager.new
+        manager.into(table)
+        manager.insert(values)
+        execute manager.to_sql, "Fixture Insert"
+      end
+
+      # Inserts a set of fixtures into the table. Overridden in adapters that require
+      # something beyond a simple insert (eg. Oracle).
+      def insert_fixtures(fixtures, table_name)
+        return if fixtures.empty?
+
+        columns = schema_cache.columns_hash(table_name)
+
+        values = fixtures.map do |fixture|
+          fixture = fixture.stringify_keys
+
+          unknown_columns = fixture.keys - columns.keys
+          if unknown_columns.any?
+            raise Fixture::FixtureError, %(table "#{table_name}" has no columns named #{unknown_columns.map(&:inspect).join(', ')}.)
+          end
+
+          columns.map do |name, column|
+            if fixture.key?(name)
+              type = lookup_cast_type_from_column(column)
+              bind = Relation::QueryAttribute.new(name, fixture[name], type)
+              with_yaml_fallback(bind.value_for_database)
+            else
+              Arel.sql("DEFAULT")
+            end
           end
         end
 
-        execute "INSERT INTO #{quote_table_name(table_name)} (#{key_list.join(', ')}) VALUES (#{value_list.join(', ')})", 'Fixture Insert'
+        table = Arel::Table.new(table_name)
+        manager = Arel::InsertManager.new
+        manager.into(table)
+        columns.each_key { |column| manager.columns << table[column] }
+        manager.values = manager.create_values_list(values)
+        execute manager.to_sql, "Fixtures Insert"
       end
 
       def empty_insert_statement_value
@@ -333,17 +394,12 @@ module ActiveRecord
       # Sanitizes the given LIMIT parameter in order to prevent SQL injection.
       #
       # The +limit+ may be anything that can evaluate to a string via #to_s. It
-      # should look like an integer, or a comma-delimited list of integers, or
-      # an Arel SQL literal.
+      # should look like an integer, or an Arel SQL literal.
       #
       # Returns Integer and Arel::Nodes::SqlLiteral limits as is.
-      # Returns the sanitized limit parameter, either as an integer, or as a
-      # string which contains a comma-delimited list of integers.
       def sanitize_limit(limit)
         if limit.is_a?(Integer) || limit.is_a?(Arel::Nodes::SqlLiteral)
           limit
-        elsif limit.to_s.include?(',')
-          Arel.sql limit.to_s.split(',').map{ |i| Integer(i) }.join(',')
         else
           Integer(limit)
         end
@@ -359,7 +415,7 @@ module ActiveRecord
       end
       alias join_to_delete join_to_update
 
-      protected
+      private
 
         # Returns a subquery for the given key using the join information.
         def subquery_for(key, select)
@@ -378,19 +434,57 @@ module ActiveRecord
         end
 
         def sql_for_insert(sql, pk, id_value, sequence_name, binds)
-          [sql, binds, pk, sequence_name]
+          [sql, binds]
         end
 
         def last_inserted_id(result)
-          row = result.rows.first
+          single_value_from_rows(result.rows)
+        end
+
+        def single_value_from_rows(rows)
+          row = rows.first
           row && row.first
         end
 
-        def binds_from_relation(relation, binds)
-          if relation.is_a?(Relation) && binds.empty?
-            relation, binds = relation.arel, relation.bound_attributes
+        def arel_from_relation(relation)
+          if relation.is_a?(Relation)
+            relation.arel
+          else
+            relation
+          end
+        end
+
+        # Fixture value is quoted by Arel, however scalar values
+        # are not quotable. In this case we want to convert
+        # the column value to YAML.
+        def with_yaml_fallback(value)
+          if value.is_a?(Hash) || value.is_a?(Array)
+            YAML.dump(value)
+          else
+            value
+          end
+        end
+
+        class PartialQueryCollector
+          def initialize
+            @parts = []
+            @binds = []
+          end
+
+          def <<(str)
+            @parts << str
+            self
+          end
+
+          def add_bind(obj)
+            @binds << obj
+            @parts << Arel::Nodes::BindParam.new(1)
+            self
+          end
+
+          def value
+            [@parts, @binds]
           end
-          [relation, binds]
         end
     end
   end
diff --git a/activerecord/lib/active_record/connection_adapters/abstract/query_cache.rb b/activerecord/lib/active_record/connection_adapters/abstract/query_cache.rb
index 0bdfd4f900..25622e34c8 100644
--- a/activerecord/lib/active_record/connection_adapters/abstract/query_cache.rb
+++ b/activerecord/lib/active_record/connection_adapters/abstract/query_cache.rb
@@ -1,9 +1,16 @@
+# frozen_string_literal: true
+
+require "concurrent/map"
+
 module ActiveRecord
   module ConnectionAdapters # :nodoc:
     module QueryCache
       class << self
         def included(base) #:nodoc:
           dirties_query_cache base, :insert, :update, :delete, :rollback_to_savepoint, :rollback_db_transaction
+
+          base.set_callback :checkout, :after, :configure_query_cache!
+          base.set_callback :checkin, :after, :disable_query_cache!
         end
 
         def dirties_query_cache(base, *method_names)
@@ -18,11 +25,32 @@ module ActiveRecord
         end
       end
 
+      module ConnectionPoolConfiguration
+        def initialize(*)
+          super
+          @query_cache_enabled = Concurrent::Map.new { false }
+        end
+
+        def enable_query_cache!
+          @query_cache_enabled[connection_cache_key(Thread.current)] = true
+          connection.enable_query_cache! if active_connection?
+        end
+
+        def disable_query_cache!
+          @query_cache_enabled.delete connection_cache_key(Thread.current)
+          connection.disable_query_cache! if active_connection?
+        end
+
+        def query_cache_enabled
+          @query_cache_enabled[connection_cache_key(Thread.current)]
+        end
+      end
+
       attr_reader :query_cache, :query_cache_enabled
 
       def initialize(*)
         super
-        @query_cache         = Hash.new { |h,sql| h[sql] = {} }
+        @query_cache         = Hash.new { |h, sql| h[sql] = {} }
         @query_cache_enabled = false
       end
 
@@ -41,6 +69,7 @@ module ActiveRecord
 
       def disable_query_cache!
         @query_cache_enabled = false
+        clear_query_cache
       end
 
       # Disable the query cache within the block.
@@ -58,14 +87,16 @@ module ActiveRecord
       # the same SQL query and repeatedly return the same result each time, silently
       # undermining the randomness you were expecting.
       def clear_query_cache
-        @query_cache.clear
+        @lock.synchronize do
+          @query_cache.clear
+        end
       end
 
       def select_all(arel, name = nil, binds = [], preparable: nil)
         if @query_cache_enabled && !locked?(arel)
-          arel, binds = binds_from_relation arel, binds
-          sql = to_sql(arel, binds)
-          cache_sql(sql, binds) { super(sql, name, binds, preparable: preparable) }
+          arel = arel_from_relation(arel)
+          sql, binds = to_sql_and_binds(arel, binds)
+          cache_sql(sql, name, binds) { super(sql, name, binds, preparable: preparable) }
         else
           super
         end
@@ -73,23 +104,37 @@ module ActiveRecord
 
       private
 
-      def cache_sql(sql, binds)
-        result =
-          if @query_cache[sql].key?(binds)
-            ActiveSupport::Notifications.instrument("sql.active_record",
-              :sql => sql, :binds => binds, :name => "CACHE", :connection_id => object_id)
-            @query_cache[sql][binds]
-          else
-            @query_cache[sql][binds] = yield
+        def cache_sql(sql, name, binds)
+          @lock.synchronize do
+            result =
+              if @query_cache[sql].key?(binds)
+                ActiveSupport::Notifications.instrument(
+                  "sql.active_record",
+                  sql: sql,
+                  binds: binds,
+                  type_casted_binds: -> { type_casted_binds(binds) },
+                  name: name,
+                  connection_id: object_id,
+                  cached: true,
+                )
+                @query_cache[sql][binds]
+              else
+                @query_cache[sql][binds] = yield
+              end
+            result.dup
           end
-        result.dup
-      end
+        end
 
-      # If arel is locked this is a SELECT ... FOR UPDATE or somesuch. Such
-      # queries should not be cached.
-      def locked?(arel)
-        arel.respond_to?(:locked) && arel.locked
-      end
+        # If arel is locked this is a SELECT ... FOR UPDATE or somesuch. Such
+        # queries should not be cached.
+        def locked?(arel)
+          arel = arel.arel if arel.is_a?(Relation)
+          arel.respond_to?(:locked) && arel.locked
+        end
+
+        def configure_query_cache!
+          enable_query_cache! if pool.query_cache_enabled
+        end
     end
   end
 end
diff --git a/activerecord/lib/active_record/connection_adapters/abstract/quoting.rb b/activerecord/lib/active_record/connection_adapters/abstract/quoting.rb
index 860ef17dca..92e46ccf9f 100644
--- a/activerecord/lib/active_record/connection_adapters/abstract/quoting.rb
+++ b/activerecord/lib/active_record/connection_adapters/abstract/quoting.rb
@@ -1,22 +1,18 @@
-require 'active_support/core_ext/big_decimal/conversions'
+# frozen_string_literal: true
+
+require "active_support/core_ext/big_decimal/conversions"
+require "active_support/multibyte/chars"
 
 module ActiveRecord
   module ConnectionAdapters # :nodoc:
     module Quoting
       # Quotes the column value to help prevent
-      # {SQL injection attacks}[http://en.wikipedia.org/wiki/SQL_injection].
-      def quote(value, column = nil)
-        # records are quoted as their primary key
-        return value.quoted_id if value.respond_to?(:quoted_id)
+      # {SQL injection attacks}[https://en.wikipedia.org/wiki/SQL_injection].
+      def quote(value)
+        value = id_value_for_database(value) if value.is_a?(Base)
 
-        if column
-          ActiveSupport::Deprecation.warn(<<-MSG.squish)
-            Passing a column to `quote` has been deprecated. It is only used
-            for type casting, which should be handled elsewhere. See
-            https://github.com/rails/arel/commit/6160bfbda1d1781c3b08a33ec4955f170e95be11
-            for more information.
-          MSG
-          value = type_cast_from_column(column, value)
+        if value.respond_to?(:value_for_database)
+          value = value.value_for_database
         end
 
         _quote(value)
@@ -26,9 +22,7 @@ module ActiveRecord
       # SQLite does not understand dates, so this method will convert a Date
       # to a String.
       def type_cast(value, column = nil)
-        if value.respond_to?(:quoted_id) && value.respond_to?(:id)
-          return value.id
-        end
+        value = id_value_for_database(value) if value.is_a?(Base)
 
         if column
           value = type_cast_from_column(column, value)
@@ -63,17 +57,6 @@ module ActiveRecord
         lookup_cast_type(column.sql_type)
       end
 
-      def fetch_type_metadata(sql_type)
-        cast_type = lookup_cast_type(sql_type)
-        SqlTypeMetadata.new(
-          sql_type: sql_type,
-          type: cast_type.type,
-          limit: cast_type.limit,
-          precision: cast_type.precision,
-          scale: cast_type.scale,
-        )
-      end
-
       # Quotes a string, escaping any ' (single quote) and \ (backslash)
       # characters.
       def quote_string(s)
@@ -112,19 +95,19 @@ module ActiveRecord
       end
 
       def quoted_true
-        "'t'"
+        "TRUE".freeze
       end
 
       def unquoted_true
-        't'
+        true
       end
 
       def quoted_false
-        "'f'"
+        "FALSE".freeze
       end
 
       def unquoted_false
-        'f'
+        false
       end
 
       # Quote date/time values for use in SQL input. Includes microseconds
@@ -147,52 +130,70 @@ module ActiveRecord
       end
 
       def quoted_time(value) # :nodoc:
-        quoted_date(value).sub(/\A2000-01-01 /, '')
+        quoted_date(value).sub(/\A2000-01-01 /, "")
       end
 
-      def prepare_binds_for_database(binds) # :nodoc:
-        binds.map(&:value_for_database)
+      def quoted_binary(value) # :nodoc:
+        "'#{quote_string(value.to_s)}'"
+      end
+
+      def type_casted_binds(binds) # :nodoc:
+        if binds.first.is_a?(Array)
+          binds.map { |column, value| type_cast(value, column) }
+        else
+          binds.map { |attr| type_cast(attr.value_for_database) }
+        end
       end
 
       private
+        def lookup_cast_type(sql_type)
+          type_map.lookup(sql_type)
+        end
 
-      def types_which_need_no_typecasting
-        [nil, Numeric, String]
-      end
-
-      def _quote(value)
-        case value
-        when String, ActiveSupport::Multibyte::Chars, Type::Binary::Data
-          "'#{quote_string(value.to_s)}'"
-        when true       then quoted_true
-        when false      then quoted_false
-        when nil        then "NULL"
-        # BigDecimals need to be put in a non-normalized form and quoted.
-        when BigDecimal then value.to_s('F')
-        when Numeric, ActiveSupport::Duration then value.to_s
-        when Type::Time::Value then "'#{quoted_time(value)}'"
-        when Date, Time then "'#{quoted_date(value)}'"
-        when Symbol     then "'#{quote_string(value.to_s)}'"
-        when Class      then "'#{value}'"
-        else raise TypeError, "can't quote #{value.class.name}"
+        def id_value_for_database(value)
+          if primary_key = value.class.primary_key
+            value.instance_variable_get(:@attributes)[primary_key].value_for_database
+          end
         end
-      end
 
-      def _type_cast(value)
-        case value
-        when Symbol, ActiveSupport::Multibyte::Chars, Type::Binary::Data
-          value.to_s
-        when true       then unquoted_true
-        when false      then unquoted_false
-        # BigDecimals need to be put in a non-normalized form and quoted.
-        when BigDecimal then value.to_s('F')
-        when Type::Time::Value then quoted_time(value)
-        when Date, Time then quoted_date(value)
-        when *types_which_need_no_typecasting
-          value
-        else raise TypeError
+        def types_which_need_no_typecasting
+          [nil, Numeric, String]
+        end
+
+        def _quote(value)
+          case value
+          when String, ActiveSupport::Multibyte::Chars
+            "'#{quote_string(value.to_s)}'"
+          when true       then quoted_true
+          when false      then quoted_false
+          when nil        then "NULL"
+          # BigDecimals need to be put in a non-normalized form and quoted.
+          when BigDecimal then value.to_s("F")
+          when Numeric, ActiveSupport::Duration then value.to_s
+          when Type::Binary::Data then quoted_binary(value)
+          when Type::Time::Value then "'#{quoted_time(value)}'"
+          when Date, Time then "'#{quoted_date(value)}'"
+          when Symbol     then "'#{quote_string(value.to_s)}'"
+          when Class      then "'#{value}'"
+          else raise TypeError, "can't quote #{value.class.name}"
+          end
+        end
+
+        def _type_cast(value)
+          case value
+          when Symbol, ActiveSupport::Multibyte::Chars, Type::Binary::Data
+            value.to_s
+          when true       then unquoted_true
+          when false      then unquoted_false
+          # BigDecimals need to be put in a non-normalized form and quoted.
+          when BigDecimal then value.to_s("F")
+          when Type::Time::Value then quoted_time(value)
+          when Date, Time then quoted_date(value)
+          when *types_which_need_no_typecasting
+            value
+          else raise TypeError
+          end
         end
-      end
     end
   end
 end
diff --git a/activerecord/lib/active_record/connection_adapters/abstract/savepoints.rb b/activerecord/lib/active_record/connection_adapters/abstract/savepoints.rb
index 3a06f75292..52a796b926 100644
--- a/activerecord/lib/active_record/connection_adapters/abstract/savepoints.rb
+++ b/activerecord/lib/active_record/connection_adapters/abstract/savepoints.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActiveRecord
   module ConnectionAdapters
     module Savepoints
diff --git a/activerecord/lib/active_record/connection_adapters/abstract/schema_creation.rb b/activerecord/lib/active_record/connection_adapters/abstract/schema_creation.rb
index 6add697eeb..4a191d337c 100644
--- a/activerecord/lib/active_record/connection_adapters/abstract/schema_creation.rb
+++ b/activerecord/lib/active_record/connection_adapters/abstract/schema_creation.rb
@@ -1,4 +1,6 @@
-require 'active_support/core_ext/string/strip'
+# frozen_string_literal: true
+
+require "active_support/core_ext/string/strip"
 
 module ActiveRecord
   module ConnectionAdapters
@@ -15,32 +17,32 @@ module ActiveRecord
         end
 
         delegate :quote_column_name, :quote_table_name, :quote_default_expression, :type_to_sql,
-          :options_include_default?, :supports_indexes_in_create?, :supports_foreign_keys?, :foreign_key_options, to: :@conn
+          :options_include_default?, :supports_indexes_in_create?, :supports_foreign_keys_in_create?, :foreign_key_options, to: :@conn
         private :quote_column_name, :quote_table_name, :quote_default_expression, :type_to_sql,
-          :options_include_default?, :supports_indexes_in_create?, :supports_foreign_keys?, :foreign_key_options
+          :options_include_default?, :supports_indexes_in_create?, :supports_foreign_keys_in_create?, :foreign_key_options
 
         private
 
           def visit_AlterTable(o)
-            sql = "ALTER TABLE #{quote_table_name(o.name)} "
-            sql << o.adds.map { |col| accept col }.join(' ')
-            sql << o.foreign_key_adds.map { |fk| visit_AddForeignKey fk }.join(' ')
-            sql << o.foreign_key_drops.map { |fk| visit_DropForeignKey fk }.join(' ')
+            sql = "ALTER TABLE #{quote_table_name(o.name)} ".dup
+            sql << o.adds.map { |col| accept col }.join(" ")
+            sql << o.foreign_key_adds.map { |fk| visit_AddForeignKey fk }.join(" ")
+            sql << o.foreign_key_drops.map { |fk| visit_DropForeignKey fk }.join(" ")
           end
 
           def visit_ColumnDefinition(o)
-            o.sql_type ||= type_to_sql(o.type, o.limit, o.precision, o.scale)
-            column_sql = "#{quote_column_name(o.name)} #{o.sql_type}"
+            o.sql_type = type_to_sql(o.type, o.options)
+            column_sql = "#{quote_column_name(o.name)} #{o.sql_type}".dup
             add_column_options!(column_sql, column_options(o)) unless o.type == :primary_key
             column_sql
           end
 
           def visit_AddColumnDefinition(o)
-            "ADD #{accept(o.column)}"
+            "ADD #{accept(o.column)}".dup
           end
 
           def visit_TableDefinition(o)
-            create_sql = "CREATE#{' TEMPORARY' if o.temporary} TABLE #{quote_table_name(o.name)} "
+            create_sql = "CREATE#{' TEMPORARY' if o.temporary} TABLE #{quote_table_name(o.name)} ".dup
 
             statements = o.columns.map { |c| accept c }
             statements << accept(o.primary_keys) if o.primary_keys
@@ -49,18 +51,18 @@ module ActiveRecord
               statements.concat(o.indexes.map { |column_name, options| index_in_create(o.name, column_name, options) })
             end
 
-            if supports_foreign_keys?
+            if supports_foreign_keys_in_create?
               statements.concat(o.foreign_keys.map { |to_table, options| foreign_key_in_create(o.name, to_table, options) })
             end
 
             create_sql << "(#{statements.join(', ')})" if statements.present?
             add_table_options!(create_sql, table_options(o))
-            create_sql << " AS #{@conn.to_sql(o.as)}" if o.as
+            create_sql << " AS #{to_sql(o.as)}" if o.as
             create_sql
           end
 
           def visit_PrimaryKeyDefinition(o)
-            "PRIMARY KEY (#{o.name.join(', ')})"
+            "PRIMARY KEY (#{o.name.map { |name| quote_column_name(name) }.join(', ')})"
           end
 
           def visit_ForeignKeyDefinition(o)
@@ -93,20 +95,11 @@ module ActiveRecord
             if options_sql = options[:options]
               create_sql << " #{options_sql}"
             end
+            create_sql
           end
 
           def column_options(o)
-            column_options = {}
-            column_options[:null] = o.null unless o.null.nil?
-            column_options[:default] = o.default unless o.default.nil?
-            column_options[:column] = o
-            column_options[:first] = o.first
-            column_options[:after] = o.after
-            column_options[:auto_increment] = o.auto_increment
-            column_options[:primary_key] = o.primary_key
-            column_options[:collation] = o.collation
-            column_options[:comment] = o.comment
-            column_options
+            o.options.merge(column: o)
           end
 
           def add_column_options!(sql, options)
@@ -124,6 +117,11 @@ module ActiveRecord
             sql
           end
 
+          def to_sql(sql)
+            sql = sql.to_sql if sql.respond_to?(:to_sql)
+            sql
+          end
+
           def foreign_key_in_create(from_table, to_table, options)
             options = foreign_key_options(from_table, to_table, options)
             accept ForeignKeyDefinition.new(from_table, to_table, options)
@@ -143,5 +141,6 @@ module ActiveRecord
           end
       end
     end
+    SchemaCreation = AbstractAdapter::SchemaCreation # :nodoc:
   end
 end
diff --git a/activerecord/lib/active_record/connection_adapters/abstract/schema_definitions.rb b/activerecord/lib/active_record/connection_adapters/abstract/schema_definitions.rb
index 8dbafc5a4b..0594b4b485 100644
--- a/activerecord/lib/active_record/connection_adapters/abstract/schema_definitions.rb
+++ b/activerecord/lib/active_record/connection_adapters/abstract/schema_definitions.rb
@@ -1,32 +1,77 @@
+# frozen_string_literal: true
+
 module ActiveRecord
   module ConnectionAdapters #:nodoc:
     # Abstract representation of an index definition on a table. Instances of
     # this type are typically created and returned by methods in database
-    # adapters. e.g. ActiveRecord::ConnectionAdapters::AbstractMysqlAdapter#indexes
-    class IndexDefinition < Struct.new(:table, :name, :unique, :columns, :lengths, :orders, :where, :type, :using, :comment) #:nodoc:
+    # adapters. e.g. ActiveRecord::ConnectionAdapters::MySQL::SchemaStatements#indexes
+    class IndexDefinition # :nodoc:
+      attr_reader :table, :name, :unique, :columns, :lengths, :orders, :opclasses, :where, :type, :using, :comment
+
+      def initialize(
+        table, name,
+        unique = false,
+        columns = [],
+        lengths: {},
+        orders: {},
+        opclasses: {},
+        where: nil,
+        type: nil,
+        using: nil,
+        comment: nil
+      )
+        @table = table
+        @name = name
+        @unique = unique
+        @columns = columns
+        @lengths = concise_options(lengths)
+        @orders = concise_options(orders)
+        @opclasses = concise_options(opclasses)
+        @where = where
+        @type = type
+        @using = using
+        @comment = comment
+      end
+
+      private
+        def concise_options(options)
+          if columns.size == options.size && options.values.uniq.size == 1
+            options.values.first
+          else
+            options
+          end
+        end
     end
 
     # Abstract representation of a column definition. Instances of this type
     # are typically created by methods in TableDefinition, and added to the
     # +columns+ attribute of said TableDefinition object, in order to be used
     # for generating a number of table creation or table changing SQL statements.
-    class ColumnDefinition < Struct.new(:name, :type, :limit, :precision, :scale, :default, :null, :first, :after, :auto_increment, :primary_key, :collation, :sql_type, :comment) #:nodoc:
-
+    ColumnDefinition = Struct.new(:name, :type, :options, :sql_type) do # :nodoc:
       def primary_key?
-        primary_key || type.to_sym == :primary_key
+        options[:primary_key]
       end
-    end
 
-    class AddColumnDefinition < Struct.new(:column) # :nodoc:
-    end
+      [:limit, :precision, :scale, :default, :null, :collation, :comment].each do |option_name|
+        module_eval <<-CODE, __FILE__, __LINE__ + 1
+          def #{option_name}
+            options[:#{option_name}]
+          end
 
-    class ChangeColumnDefinition < Struct.new(:column, :name) #:nodoc:
+          def #{option_name}=(value)
+            options[:#{option_name}] = value
+          end
+        CODE
+      end
     end
 
-    class PrimaryKeyDefinition < Struct.new(:name) # :nodoc:
-    end
+    AddColumnDefinition = Struct.new(:column) # :nodoc:
 
-    class ForeignKeyDefinition < Struct.new(:from_table, :to_table, :options) #:nodoc:
+    ChangeColumnDefinition = Struct.new(:column, :name) #:nodoc:
+
+    PrimaryKeyDefinition = Struct.new(:name) # :nodoc:
+
+    ForeignKeyDefinition = Struct.new(:from_table, :to_table, :options) do #:nodoc:
       def name
         options[:name]
       end
@@ -51,6 +96,11 @@ module ActiveRecord
         options[:primary_key] != default_primary_key
       end
 
+      def validate?
+        options.fetch(:validate, true)
+      end
+      alias validated? validate?
+
       def defined_for?(to_table_ord = nil, to_table: nil, **options)
         if to_table_ord
           self.to_table == to_table_ord.to_s
@@ -61,9 +111,9 @@ module ActiveRecord
       end
 
       private
-      def default_primary_key
-        "id"
-      end
+        def default_primary_key
+          "id"
+        end
     end
 
     class ReferenceDefinition # :nodoc:
@@ -72,7 +122,7 @@ module ActiveRecord
         polymorphic: false,
         index: true,
         foreign_key: false,
-        type: :integer,
+        type: :bigint,
         **options
       )
         @name = name
@@ -101,53 +151,51 @@ module ActiveRecord
         end
       end
 
+      # TODO Change this to private once we've dropped Ruby 2.2 support.
+      # Workaround for Ruby 2.2 "private attribute?" warning.
       protected
 
-      attr_reader :name, :polymorphic, :index, :foreign_key, :type, :options
+        attr_reader :name, :polymorphic, :index, :foreign_key, :type, :options
 
       private
 
-      def as_options(value, default = {})
-        if value.is_a?(Hash)
-          value
-        else
-          default
+        def as_options(value)
+          value.is_a?(Hash) ? value : {}
         end
-      end
 
-      def polymorphic_options
-        as_options(polymorphic, options)
-      end
+        def polymorphic_options
+          as_options(polymorphic).merge(options.slice(:null, :first, :after))
+        end
 
-      def index_options
-        as_options(index)
-      end
+        def index_options
+          as_options(index)
+        end
 
-      def foreign_key_options
-        as_options(foreign_key).merge(column: column_name)
-      end
+        def foreign_key_options
+          as_options(foreign_key).merge(column: column_name)
+        end
 
-      def columns
-        result = [[column_name, type, options]]
-        if polymorphic
-          result.unshift(["#{name}_type", :string, polymorphic_options])
+        def columns
+          result = [[column_name, type, options]]
+          if polymorphic
+            result.unshift(["#{name}_type", :string, polymorphic_options])
+          end
+          result
         end
-        result
-      end
 
-      def column_name
-        "#{name}_id"
-      end
+        def column_name
+          "#{name}_id"
+        end
 
-      def column_names
-        columns.map(&:first)
-      end
+        def column_names
+          columns.map(&:first)
+        end
 
-      def foreign_table_name
-        foreign_key_options.fetch(:to_table) do
-          Base.pluralize_table_names ? name.to_s.pluralize : name
+        def foreign_table_name
+          foreign_key_options.fetch(:to_table) do
+            Base.pluralize_table_names ? name.to_s.pluralize : name
+          end
         end
-      end
     end
 
     module ColumnMethods
@@ -172,10 +220,12 @@ module ActiveRecord
         :decimal,
         :float,
         :integer,
+        :json,
         :string,
         :text,
         :time,
         :timestamp,
+        :virtual,
       ].each do |column_type|
         module_eval <<-CODE, __FILE__, __LINE__ + 1
           def #{column_type}(*args, **options)
@@ -212,7 +262,7 @@ module ActiveRecord
 
       def initialize(name, temporary = false, options = nil, as = nil, comment: nil)
         @columns_hash = {}
-        @indexes = {}
+        @indexes = []
         @foreign_keys = []
         @primary_keys = nil
         @temporary = temporary
@@ -304,7 +354,7 @@ module ActiveRecord
       #   end
       def column(name, type, options = {})
         name = name.to_s
-        type = type.to_sym
+        type = type.to_sym if type
         options = options.dup
 
         if @columns_hash[name] && @columns_hash[name].primary_key?
@@ -328,7 +378,7 @@ module ActiveRecord
       #
       #   index(:account_id, name: 'index_projects_on_account_id')
       def index(column_name, options = {})
-        indexes[column_name] = options
+        indexes << [column_name, options]
       end
 
       def foreign_key(table_name, options = {}) # :nodoc:
@@ -342,9 +392,7 @@ module ActiveRecord
       # <tt>:updated_at</tt> to the table. See {connection.add_timestamps}[rdoc-ref:SchemaStatements#add_timestamps]
       #
       #   t.timestamps null: false
-      def timestamps(*args)
-        options = args.extract_options!
-
+      def timestamps(**options)
         options[:null] = false if options[:null].nil?
 
         column(:created_at, :datetime, options)
@@ -358,38 +406,38 @@ module ActiveRecord
       #
       # See {connection.add_reference}[rdoc-ref:SchemaStatements#add_reference] for details of the options you can use.
       def references(*args, **options)
-        args.each do |col|
-          ReferenceDefinition.new(col, **options).add_to(self)
+        args.each do |ref_name|
+          ReferenceDefinition.new(ref_name, options).add_to(self)
         end
       end
       alias :belongs_to :references
 
-      def new_column_definition(name, type, options) # :nodoc:
+      def new_column_definition(name, type, **options) # :nodoc:
+        if integer_like_primary_key?(type, options)
+          type = integer_like_primary_key_type(type, options)
+        end
         type = aliased_types(type.to_s, type)
-        column = create_column_definition name, type
-
-        column.limit       = options[:limit]
-        column.precision   = options[:precision]
-        column.scale       = options[:scale]
-        column.default     = options[:default]
-        column.null        = options[:null]
-        column.first       = options[:first]
-        column.after       = options[:after]
-        column.auto_increment = options[:auto_increment]
-        column.primary_key = type == :primary_key || options[:primary_key]
-        column.collation   = options[:collation]
-        column.comment     = options[:comment]
-        column
+        options[:primary_key] ||= type == :primary_key
+        options[:null] = false if options[:primary_key]
+        create_column_definition(name, type, options)
       end
 
       private
-      def create_column_definition(name, type)
-        ColumnDefinition.new name, type
-      end
+        def create_column_definition(name, type, options)
+          ColumnDefinition.new(name, type, options)
+        end
 
-      def aliased_types(name, fallback)
-        'timestamp' == name ? :datetime : fallback
-      end
+        def aliased_types(name, fallback)
+          "timestamp" == name ? :datetime : fallback
+        end
+
+        def integer_like_primary_key?(type, options)
+          options[:primary_key] && [:integer, :bigint].include?(type) && !options.key?(:default)
+        end
+
+        def integer_like_primary_key_type(type, options)
+          type
+        end
     end
 
     class AlterTable # :nodoc:
@@ -478,7 +526,7 @@ module ActiveRecord
 
       # Checks to see if a column exists.
       #
-      # t.string(:name) unless t.column_exists?(:name, :string)
+      #  t.string(:name) unless t.column_exists?(:name, :string)
       #
       # See {connection.column_exists?}[rdoc-ref:SchemaStatements#column_exists?]
       def column_exists?(column_name, type = nil, options = {})
@@ -499,9 +547,9 @@ module ActiveRecord
 
       # Checks to see if an index exists.
       #
-      # unless t.index_exists?(:branch_id)
-      #   t.index(:branch_id)
-      # end
+      #  unless t.index_exists?(:branch_id)
+      #    t.index(:branch_id)
+      #  end
       #
       # See {connection.index_exists?}[rdoc-ref:SchemaStatements#index_exists?]
       def index_exists?(column_name, options = {})
@@ -592,8 +640,7 @@ module ActiveRecord
       #  t.belongs_to(:supplier, foreign_key: true)
       #
       # See {connection.add_reference}[rdoc-ref:SchemaStatements#add_reference] for details of the options you can use.
-      def references(*args)
-        options = args.extract_options!
+      def references(*args, **options)
         args.each do |ref_name|
           @base.add_reference(name, ref_name, options)
         end
@@ -606,8 +653,7 @@ module ActiveRecord
       #  t.remove_belongs_to(:supplier, polymorphic: true)
       #
       # See {connection.remove_reference}[rdoc-ref:SchemaStatements#remove_reference]
-      def remove_references(*args)
-        options = args.extract_options!
+      def remove_references(*args, **options)
         args.each do |ref_name|
           @base.remove_reference(name, ref_name, options)
         end
diff --git a/activerecord/lib/active_record/connection_adapters/abstract/schema_dumper.rb b/activerecord/lib/active_record/connection_adapters/abstract/schema_dumper.rb
index 677a4c6bd0..1926603474 100644
--- a/activerecord/lib/active_record/connection_adapters/abstract/schema_dumper.rb
+++ b/activerecord/lib/active_record/connection_adapters/abstract/schema_dumper.rb
@@ -1,105 +1,95 @@
+# frozen_string_literal: true
+
+require "active_support/core_ext/hash/compact"
+
 module ActiveRecord
   module ConnectionAdapters # :nodoc:
-    # The goal of this module is to move Adapter specific column
-    # definitions to the Adapter instead of having it in the schema
-    # dumper itself. This code represents the normal case.
-    # We can then redefine how certain data types may be handled in the schema dumper on the
-    # Adapter level by over-writing this code inside the database specific adapters
-    module ColumnDumper
-      def column_spec(column)
-        spec = Hash[prepare_column_options(column).map { |k, v| [k, "#{k}: #{v}"] }]
-        spec[:name] = column.name.inspect
-        spec[:type] = schema_type(column).to_s
-        spec
-      end
-
-      def column_spec_for_primary_key(column)
-        return {} if default_primary_key?(column)
-        spec = { id: schema_type(column).inspect }
-        spec.merge!(prepare_column_options(column).except!(:null))
+    class SchemaDumper < SchemaDumper # :nodoc:
+      def self.create(connection, options)
+        new(connection, options)
       end
 
-      # This can be overridden on an Adapter level basis to support other
-      # extended datatypes (Example: Adding an array option in the
-      # PostgreSQL::ColumnDumper)
-      def prepare_column_options(column)
-        spec = {}
-
-        if limit = schema_limit(column)
-          spec[:limit] = limit
+      private
+        def column_spec(column)
+          [schema_type_with_virtual(column), prepare_column_options(column)]
         end
 
-        if precision = schema_precision(column)
-          spec[:precision] = precision
+        def column_spec_for_primary_key(column)
+          return {} if default_primary_key?(column)
+          spec = { id: schema_type(column).inspect }
+          spec.merge!(prepare_column_options(column).except!(:null))
+          spec[:default] ||= "nil" if explicit_primary_key_default?(column)
+          spec
         end
 
-        if scale = schema_scale(column)
-          spec[:scale] = scale
+        def prepare_column_options(column)
+          spec = {}
+          spec[:limit] = schema_limit(column)
+          spec[:precision] = schema_precision(column)
+          spec[:scale] = schema_scale(column)
+          spec[:default] = schema_default(column)
+          spec[:null] = "false" unless column.null
+          spec[:collation] = schema_collation(column)
+          spec[:comment] = column.comment.inspect if column.comment.present?
+          spec.compact!
+          spec
         end
 
-        default = schema_default(column) if column.has_default?
-        spec[:default]   = default unless default.nil?
-
-        spec[:null] = 'false' unless column.null
-
-        if collation = schema_collation(column)
-          spec[:collation] = collation
+        def default_primary_key?(column)
+          schema_type(column) == :bigint
         end
 
-        spec[:comment] = column.comment.inspect if column.comment.present?
-
-        spec
-      end
-
-      # Lists the valid migration options
-      def migration_keys
-        [:name, :limit, :precision, :scale, :default, :null, :collation, :comment]
-      end
-
-      private
+        def explicit_primary_key_default?(column)
+          false
+        end
 
-      def default_primary_key?(column)
-        schema_type(column) == :integer
-      end
+        def schema_type_with_virtual(column)
+          if @connection.supports_virtual_columns? && column.virtual?
+            :virtual
+          else
+            schema_type(column)
+          end
+        end
 
-      def schema_type(column)
-        if column.bigint?
-          :bigint
-        else
-          column.type
+        def schema_type(column)
+          if column.bigint?
+            :bigint
+          else
+            column.type
+          end
         end
-      end
 
-      def schema_limit(column)
-        limit = column.limit unless column.bigint?
-        limit.inspect if limit && limit != native_database_types[column.type][:limit]
-      end
+        def schema_limit(column)
+          limit = column.limit unless column.bigint?
+          limit.inspect if limit && limit != @connection.native_database_types[column.type][:limit]
+        end
 
-      def schema_precision(column)
-        column.precision.inspect if column.precision
-      end
+        def schema_precision(column)
+          column.precision.inspect if column.precision
+        end
 
-      def schema_scale(column)
-        column.scale.inspect if column.scale
-      end
+        def schema_scale(column)
+          column.scale.inspect if column.scale
+        end
 
-      def schema_default(column)
-        type = lookup_cast_type_from_column(column)
-        default = type.deserialize(column.default)
-        if default.nil?
-          schema_expression(column)
-        else
-          type.type_cast_for_schema(default)
+        def schema_default(column)
+          return unless column.has_default?
+          type = @connection.lookup_cast_type_from_column(column)
+          default = type.deserialize(column.default)
+          if default.nil?
+            schema_expression(column)
+          else
+            type.type_cast_for_schema(default)
+          end
         end
-      end
 
-      def schema_expression(column)
-        "-> { #{column.default_function.inspect} }" if column.default_function
-      end
+        def schema_expression(column)
+          "-> { #{column.default_function.inspect} }" if column.default_function
+        end
 
-      def schema_collation(column)
-        column.collation.inspect if column.collation
-      end
+        def schema_collation(column)
+          column.collation.inspect if column.collation
+        end
     end
   end
 end
diff --git a/activerecord/lib/active_record/connection_adapters/abstract/schema_statements.rb b/activerecord/lib/active_record/connection_adapters/abstract/schema_statements.rb
index eec0bc8518..4f58b0242c 100644
--- a/activerecord/lib/active_record/connection_adapters/abstract/schema_statements.rb
+++ b/activerecord/lib/active_record/connection_adapters/abstract/schema_statements.rb
@@ -1,6 +1,8 @@
-require 'active_record/migration/join_table'
-require 'active_support/core_ext/string/access'
-require 'digest'
+# frozen_string_literal: true
+
+require "active_record/migration/join_table"
+require "active_support/core_ext/string/access"
+require "digest/sha2"
 
 module ActiveRecord
   module ConnectionAdapters # :nodoc:
@@ -25,12 +27,14 @@ module ActiveRecord
 
       # Truncates a table alias according to the limits of the current adapter.
       def table_alias_for(table_name)
-        table_name[0...table_alias_length].tr('.', '_')
+        table_name[0...table_alias_length].tr(".", "_")
       end
 
       # Returns the relation names useable to back Active Record models.
       # For most adapters this means all #tables and #views.
       def data_sources
+        query_values(data_source_sql, "SCHEMA")
+      rescue NotImplementedError
         tables | views
       end
 
@@ -39,12 +43,14 @@ module ActiveRecord
       #   data_source_exists?(:ebooks)
       #
       def data_source_exists?(name)
+        query_values(data_source_sql(name), "SCHEMA").any? if name.present?
+      rescue NotImplementedError
         data_sources.include?(name.to_s)
       end
 
       # Returns an array of table names defined in the database.
-      def tables(name = nil)
-        raise NotImplementedError, "#tables is not implemented"
+      def tables
+        query_values(data_source_sql(type: "BASE TABLE"), "SCHEMA")
       end
 
       # Checks to see if the table +table_name+ exists on the database.
@@ -52,12 +58,14 @@ module ActiveRecord
       #   table_exists?(:developers)
       #
       def table_exists?(table_name)
+        query_values(data_source_sql(table_name, type: "BASE TABLE"), "SCHEMA").any? if table_name.present?
+      rescue NotImplementedError
         tables.include?(table_name.to_s)
       end
 
       # Returns an array of view names defined in the database.
       def views
-        raise NotImplementedError, "#views is not implemented"
+        query_values(data_source_sql(type: "VIEW"), "SCHEMA")
       end
 
       # Checks to see if the view +view_name+ exists on the database.
@@ -65,11 +73,15 @@ module ActiveRecord
       #   view_exists?(:ebooks)
       #
       def view_exists?(view_name)
+        query_values(data_source_sql(view_name, type: "VIEW"), "SCHEMA").any? if view_name.present?
+      rescue NotImplementedError
         views.include?(view_name.to_s)
       end
 
       # Returns an array of indexes for the given table.
-      # def indexes(table_name, name = nil) end
+      def indexes(table_name)
+        raise NotImplementedError, "#indexes is not implemented"
+      end
 
       # Checks to see if an index exists on a table for a given index definition.
       #
@@ -95,10 +107,12 @@ module ActiveRecord
         indexes(table_name).any? { |i| checks.all? { |check| check[i] } }
       end
 
-      # Returns an array of Column objects for the table specified by +table_name+.
-      # See the concrete implementation for details on the expected parameter values.
+      # Returns an array of +Column+ objects for the table specified by +table_name+.
       def columns(table_name)
-        raise NotImplementedError, "#columns is not implemented"
+        table_name = table_name.to_s
+        column_definitions(table_name).map do |field|
+          new_column_from_field(table_name, field)
+        end
       end
 
       # Checks to see if a column exists in a given table.
@@ -120,7 +134,7 @@ module ActiveRecord
         checks = []
         checks << lambda { |c| c.name == column_name }
         checks << lambda { |c| c.type == type } if type
-        (migration_keys - [:name]).each do |attr|
+        column_options_keys.each do |attr|
           checks << lambda { |c| c.send(attr) == options[attr] } if options.key?(attr)
         end
 
@@ -129,14 +143,9 @@ module ActiveRecord
 
       # Returns just a table's primary key
       def primary_key(table_name)
-        pks = primary_keys(table_name)
-        warn <<-WARNING.strip_heredoc if pks.count > 1
-          WARNING: Rails does not support composite primary key.
-
-          #{table_name} has composite primary key. Composite primary key is ignored.
-        WARNING
-
-        pks.first if pks.one?
+        pk = primary_keys(table_name)
+        pk = pk.first unless pk.size > 1
+        pk
       end
 
       # Creates a new table with the name +table_name+. +table_name+ may either
@@ -179,7 +188,9 @@ module ActiveRecord
       #   A Symbol can be used to specify the type of the generated primary key column.
       # [<tt>:primary_key</tt>]
       #   The name of the primary key, if one is to be added automatically.
-      #   Defaults to +id+. If <tt>:id</tt> is false this option is ignored.
+      #   Defaults to +id+. If <tt>:id</tt> is false, then this option is ignored.
+      #
+      #   If an array is passed, a composite primary key will be created.
       #
       #   Note that Active Record models will automatically detect their
       #   primary key. This can be avoided by using
@@ -205,7 +216,7 @@ module ActiveRecord
       # generates:
       #
       #   CREATE TABLE suppliers (
-      #     id int auto_increment PRIMARY KEY
+      #     id bigint auto_increment PRIMARY KEY
       #   ) ENGINE=InnoDB DEFAULT CHARSET=utf8
       #
       # ====== Rename the primary key column
@@ -217,7 +228,7 @@ module ActiveRecord
       # generates:
       #
       #   CREATE TABLE objects (
-      #     guid int auto_increment PRIMARY KEY,
+      #     guid bigint auto_increment PRIMARY KEY,
       #     name varchar(80)
       #   )
       #
@@ -234,18 +245,35 @@ module ActiveRecord
       #     label varchar
       #   )
       #
+      # ====== Create a composite primary key
+      #
+      #   create_table(:orders, primary_key: [:product_id, :client_id]) do |t|
+      #     t.belongs_to :product
+      #     t.belongs_to :client
+      #   end
+      #
+      # generates:
+      #
+      #   CREATE TABLE order (
+      #       product_id bigint NOT NULL,
+      #       client_id bigint NOT NULL
+      #   );
+      #
+      #   ALTER TABLE ONLY "orders"
+      #     ADD CONSTRAINT orders_pkey PRIMARY KEY (product_id, client_id);
+      #
       # ====== Do not add a primary key column
       #
       #   create_table(:categories_suppliers, id: false) do |t|
-      #     t.column :category_id, :integer
-      #     t.column :supplier_id, :integer
+      #     t.column :category_id, :bigint
+      #     t.column :supplier_id, :bigint
       #   end
       #
       # generates:
       #
       #   CREATE TABLE categories_suppliers (
-      #     category_id int,
-      #     supplier_id int
+      #     category_id bigint,
+      #     supplier_id bigint
       #   )
       #
       # ====== Create a temporary table based on a query
@@ -276,23 +304,23 @@ module ActiveRecord
 
         yield td if block_given?
 
-        if options[:force] && data_source_exists?(table_name)
-          drop_table(table_name, options)
+        if options[:force]
+          drop_table(table_name, **options, if_exists: true)
         end
 
         result = execute schema_creation.accept td
 
         unless supports_indexes_in_create?
-          td.indexes.each_pair do |column_name, index_options|
+          td.indexes.each do |column_name, index_options|
             add_index(table_name, column_name, index_options)
           end
         end
 
         if supports_comments? && !supports_comments_in_create?
-          change_table_comment(table_name, comment) if comment
+          change_table_comment(table_name, comment) if comment.present?
 
           td.columns.each do |column|
-            change_column_comment(table_name, column.name, column.comment) if column.comment
+            change_column_comment(table_name, column.name, column.comment) if column.comment.present?
           end
         end
 
@@ -305,9 +333,9 @@ module ActiveRecord
       #   # Creates a table called 'assemblies_parts' with no id.
       #   create_join_table(:assemblies, :parts)
       #
-      # You can pass a +options+ hash can include the following keys:
+      # You can pass an +options+ hash which can include the following keys:
       # [<tt>:table_name</tt>]
-      #   Sets the table name overriding the default
+      #   Sets the table name, overriding the default.
       # [<tt>:column_options</tt>]
       #   Any extra options you want appended to the columns definition.
       # [<tt>:options</tt>]
@@ -333,22 +361,20 @@ module ActiveRecord
       # generates:
       #
       #   CREATE TABLE assemblies_parts (
-      #     assembly_id int NOT NULL,
-      #     part_id int NOT NULL,
+      #     assembly_id bigint NOT NULL,
+      #     part_id bigint NOT NULL,
       #   ) ENGINE=InnoDB DEFAULT CHARSET=utf8
       #
-      def create_join_table(table_1, table_2, options = {})
+      def create_join_table(table_1, table_2, column_options: {}, **options)
         join_table_name = find_join_table_name(table_1, table_2, options)
 
-        column_options = options.delete(:column_options) || {}
-        column_options.reverse_merge!(null: false)
-        type = column_options.delete(:type) || :integer
+        column_options.reverse_merge!(null: false, index: false)
 
-        t1_column, t2_column = [table_1, table_2].map{ |t| t.to_s.singularize.foreign_key }
+        t1_ref, t2_ref = [table_1, table_2].map { |t| t.to_s.singularize }
 
         create_table(join_table_name, options.merge!(id: false)) do |td|
-          td.send type, t1_column, column_options
-          td.send type, t2_column, column_options
+          td.references t1_ref, column_options
+          td.references t2_ref, column_options
           yield td if block_given?
         end
       end
@@ -380,6 +406,8 @@ module ActiveRecord
       #
       #   Defaults to false.
       #
+      #   Only supported on the MySQL adapter, ignored elsewhere.
+      #
       # ====== Add a column
       #
       #   change_table(:suppliers) do |t|
@@ -404,7 +432,7 @@ module ActiveRecord
       #     t.references :company
       #   end
       #
-      # Creates a <tt>company_id(integer)</tt> column.
+      # Creates a <tt>company_id(bigint)</tt> column.
       #
       # ====== Add a polymorphic foreign key column
       #
@@ -412,7 +440,7 @@ module ActiveRecord
       #    t.belongs_to :company, polymorphic: true
       #  end
       #
-      # Creates <tt>company_type(varchar)</tt> and <tt>company_id(integer)</tt> columns.
+      # Creates <tt>company_type(varchar)</tt> and <tt>company_id(bigint)</tt> columns.
       #
       # ====== Remove a column
       #
@@ -433,7 +461,7 @@ module ActiveRecord
       #    t.remove_index :company_id
       #  end
       #
-      # See also Table for details on all of the various column transformation.
+      # See also Table for details on all of the various column transformations.
       def change_table(table_name, options = {})
         if supports_bulk_alter? && options[:bulk]
           recorder = ActiveRecord::Migration::CommandRecorder.new(self)
@@ -483,19 +511,21 @@ module ActiveRecord
       #
       # Available options are (none of these exists by default):
       # * <tt>:limit</tt> -
-      #   Requests a maximum column length. This is number of characters for a <tt>:string</tt> column
+      #   Requests a maximum column length. This is the number of characters for a <tt>:string</tt> column
       #   and number of bytes for <tt>:text</tt>, <tt>:binary</tt> and <tt>:integer</tt> columns.
+      #   This option is ignored by some backends.
       # * <tt>:default</tt> -
-      #   The column's default value. Use nil for NULL.
+      #   The column's default value. Use +nil+ for +NULL+.
       # * <tt>:null</tt> -
-      #   Allows or disallows +NULL+ values in the column. This option could
-      #   have been named <tt>:null_allowed</tt>.
+      #   Allows or disallows +NULL+ values in the column.
       # * <tt>:precision</tt> -
       #   Specifies the precision for the <tt>:decimal</tt> and <tt>:numeric</tt> columns.
       # * <tt>:scale</tt> -
       #   Specifies the scale for the <tt>:decimal</tt> and <tt>:numeric</tt> columns.
+      # * <tt>:comment</tt> -
+      #   Specifies the comment for the column. This option is ignored by some backends.
       #
-      # Note: The precision is the total number of significant digits
+      # Note: The precision is the total number of significant digits,
       # and the scale is the number of digits that can be stored following
       # the decimal point. For example, the number 123.45 has a precision of 5
       # and a scale of 2. A decimal with a precision of 5 and a scale of 2 can
@@ -516,7 +546,7 @@ module ActiveRecord
       #   Default is (38,0).
       # * DB2: <tt>:precision</tt> [1..63], <tt>:scale</tt> [0..62].
       #   Default unknown.
-      # * SqlServer?: <tt>:precision</tt> [1..38], <tt>:scale</tt> [0..38].
+      # * SqlServer: <tt>:precision</tt> [1..38], <tt>:scale</tt> [0..38].
       #   Default (38,0).
       #
       # == Examples
@@ -538,6 +568,10 @@ module ActiveRecord
       #  add_column(:measurements, :huge_integer, :decimal, precision: 30)
       #  # ALTER TABLE "measurements" ADD "huge_integer" decimal(30)
       #
+      #  # Defines a column that stores an array of a type.
+      #  add_column(:users, :skills, :text, array: true)
+      #  # ALTER TABLE "users" ADD "skills" text[]
+      #
       #  # Defines a column with a database-specific type.
       #  add_column(:shapes, :triangle, 'polygon')
       #  # ALTER TABLE "shapes" ADD "triangle" polygon
@@ -564,9 +598,9 @@ module ActiveRecord
       #
       # The +type+ and +options+ parameters will be ignored if present. It can be helpful
       # to provide these in a migration's +change+ method so it can be reverted.
-      # In that case, +type+ and +options+ will be used by add_column.
+      # In that case, +type+ and +options+ will be used by #add_column.
       def remove_column(table_name, column_name, type = nil, options = {})
-        execute "ALTER TABLE #{quote_table_name(table_name)} DROP #{quote_column_name(column_name)}"
+        execute "ALTER TABLE #{quote_table_name(table_name)} #{remove_column_for_alter(table_name, column_name, type, options)}"
       end
 
       # Changes the column's definition according to the new options.
@@ -704,6 +738,28 @@ module ActiveRecord
       #
       # Note: only supported by PostgreSQL and MySQL
       #
+      # ====== Creating an index with a specific operator class
+      #
+      #   add_index(:developers, :name, using: 'gist', opclass: :gist_trgm_ops)
+      #
+      # generates:
+      #
+      #   CREATE INDEX developers_on_name ON developers USING gist (name gist_trgm_ops) -- PostgreSQL
+      #
+      #   add_index(:developers, [:name, :city], using: 'gist', opclass: { city: :gist_trgm_ops })
+      #
+      # generates:
+      #
+      #   CREATE INDEX developers_on_name_and_city ON developers USING gist (name, city gist_trgm_ops) -- PostgreSQL
+      #
+      #   add_index(:developers, [:name, :city], using: 'gist', opclass: :gist_trgm_ops)
+      #
+      # generates:
+      #
+      #   CREATE INDEX developers_on_name_and_city ON developers USING gist (name gist_trgm_ops, city gist_trgm_ops) -- PostgreSQL
+      #
+      # Note: only supported by PostgreSQL
+      #
       # ====== Creating an index with a specific type
       #
       #   add_index(:developers, :name, type: :fulltext)
@@ -750,7 +806,7 @@ module ActiveRecord
       def rename_index(table_name, old_name, new_name)
         validate_index_length!(table_name, new_name)
 
-        # this is a naive implementation; some DBs may support this more efficiently (Postgres, for instance)
+        # this is a naive implementation; some DBs may support this more efficiently (PostgreSQL, for instance)
         old_index_def = indexes(table_name).detect { |i| i.name == old_name }
         return unless old_index_def
         add_index(table_name, old_index_def.columns, name: new_name, unique: old_index_def.unique)
@@ -767,30 +823,26 @@ module ActiveRecord
             raise ArgumentError, "You must specify the index name"
           end
         else
-          index_name(table_name, :column => options)
+          index_name(table_name, index_name_options(options))
         end
       end
 
       # Verifies the existence of an index with a given name.
-      #
-      # The default argument is returned if the underlying implementation does not define the indexes method,
-      # as there's no way to determine the correct answer in that case.
-      def index_name_exists?(table_name, index_name, default)
-        return default unless respond_to?(:indexes)
+      def index_name_exists?(table_name, index_name)
         index_name = index_name.to_s
         indexes(table_name).detect { |i| i.name == index_name }
       end
 
-      # Adds a reference. The reference column is an integer by default,
+      # Adds a reference. The reference column is a bigint by default,
       # the <tt>:type</tt> option can be used to specify a different type.
       # Optionally adds a +_type+ column, if <tt>:polymorphic</tt> option is provided.
       # #add_reference and #add_belongs_to are acceptable.
       #
       # The +options+ hash can include the following keys:
       # [<tt>:type</tt>]
-      #   The reference column type. Defaults to +:integer+.
+      #   The reference column type. Defaults to +:bigint+.
       # [<tt>:index</tt>]
-      #   Add an appropriate index. Defaults to false.
+      #   Add an appropriate index. Defaults to true.
       #   See #add_index for usage of this option.
       # [<tt>:foreign_key</tt>]
       #   Add an appropriate foreign key constraint. Defaults to false.
@@ -799,7 +851,7 @@ module ActiveRecord
       # [<tt>:null</tt>]
       #   Whether the column allows nulls. Defaults to true.
       #
-      # ====== Create a user_id integer column
+      # ====== Create a user_id bigint column
       #
       #   add_reference(:products, :user)
       #
@@ -827,8 +879,8 @@ module ActiveRecord
       #
       #   add_reference(:products, :supplier, foreign_key: {to_table: :firms})
       #
-      def add_reference(table_name, *args)
-        ReferenceDefinition.new(*args).add_to(update_table_definition(table_name, self))
+      def add_reference(table_name, ref_name, **options)
+        ReferenceDefinition.new(ref_name, options).add_to(update_table_definition(table_name, self))
       end
       alias :add_belongs_to :add_reference
 
@@ -855,6 +907,7 @@ module ActiveRecord
           else
             foreign_key_options = { to_table: reference_name }
           end
+          foreign_key_options[:column] ||= "#{ref_name}_id"
           remove_foreign_key(table_name, **foreign_key_options)
         end
 
@@ -911,6 +964,8 @@ module ActiveRecord
       #   Action that happens <tt>ON DELETE</tt>. Valid values are +:nullify+, +:cascade+ and +:restrict+
       # [<tt>:on_update</tt>]
       #   Action that happens <tt>ON UPDATE</tt>. Valid values are +:nullify+, +:cascade+ and +:restrict+
+      # [<tt>:validate</tt>]
+      #   (Postgres only) Specify whether or not the constraint should be validated. Defaults to +true+.
       def add_foreign_key(from_table, to_table, options = {})
         return unless supports_foreign_keys?
 
@@ -952,29 +1007,19 @@ module ActiveRecord
 
       # Checks to see if a foreign key exists on a table for a given foreign key definition.
       #
-      #   # Check a foreign key exists
+      #   # Checks to see if a foreign key exists.
       #   foreign_key_exists?(:accounts, :branches)
       #
-      #   # Check a foreign key on a specified column exists
+      #   # Checks to see if a foreign key on a specified column exists.
       #   foreign_key_exists?(:accounts, column: :owner_id)
       #
-      #   # Check a foreign key with a custom name exists
+      #   # Checks to see if a foreign key with a custom name exists.
       #   foreign_key_exists?(:accounts, name: "special_fk_name")
       #
       def foreign_key_exists?(from_table, options_or_to_table = {})
         foreign_key_for(from_table, options_or_to_table).present?
       end
 
-      def foreign_key_for(from_table, options_or_to_table = {}) # :nodoc:
-        return unless supports_foreign_keys?
-        foreign_keys(from_table).detect {|fk| fk.defined_for? options_or_to_table }
-      end
-
-      def foreign_key_for!(from_table, options_or_to_table = {}) # :nodoc:
-        foreign_key_for(from_table, options_or_to_table) or \
-          raise ArgumentError, "Table '#{from_table}' has no foreign key for #{options_or_to_table}"
-      end
-
       def foreign_key_column_for(table_name) # :nodoc:
         prefix = Base.table_name_prefix
         suffix = Base.table_name_suffix
@@ -990,33 +1035,8 @@ module ActiveRecord
       end
 
       def dump_schema_information #:nodoc:
-        versions = ActiveRecord::SchemaMigration.order('version').pluck(:version)
-        insert_versions_sql(versions)
-      end
-
-      def insert_versions_sql(versions) # :nodoc:
-        sm_table = ActiveRecord::Migrator.schema_migrations_table_name
-
-        if supports_multi_insert?
-          sql = "INSERT INTO #{sm_table} (version) VALUES "
-          sql << versions.map {|v| "('#{v}')" }.join(', ')
-          sql << ";\n\n"
-          sql
-        else
-          versions.map { |version|
-            "INSERT INTO #{sm_table} (version) VALUES ('#{version}');"
-          }.join "\n\n"
-        end
-      end
-
-      # Should not be called normally, but this operation is non-destructive.
-      # The migrations module handles this automatically.
-      def initialize_schema_migrations_table
-        ActiveRecord::SchemaMigration.create_table
-      end
-
-      def initialize_internal_metadata_table
-        ActiveRecord::InternalMetadata.create_table
+        versions = ActiveRecord::SchemaMigration.all_versions
+        insert_versions_sql(versions) if versions.any?
       end
 
       def internal_string_options_for_primary_key # :nodoc:
@@ -1026,29 +1046,35 @@ module ActiveRecord
       def assume_migrated_upto_version(version, migrations_paths)
         migrations_paths = Array(migrations_paths)
         version = version.to_i
-        sm_table = quote_table_name(ActiveRecord::Migrator.schema_migrations_table_name)
+        sm_table = quote_table_name(ActiveRecord::SchemaMigration.table_name)
 
-        migrated = select_values("SELECT version FROM #{sm_table}").map(&:to_i)
-        paths = migrations_paths.map {|p| "#{p}/[0-9]*_*.rb" }
-        versions = Dir[*paths].map do |filename|
-          filename.split('/').last.split('_').first.to_i
+        migrated = ActiveRecord::SchemaMigration.all_versions.map(&:to_i)
+        versions = ActiveRecord::Migrator.migration_files(migrations_paths).map do |file|
+          ActiveRecord::Migrator.parse_migration_filename(file).first.to_i
         end
 
         unless migrated.include?(version)
-          execute "INSERT INTO #{sm_table} (version) VALUES ('#{version}')"
+          execute "INSERT INTO #{sm_table} (version) VALUES (#{quote(version)})"
         end
 
-        inserting = (versions - migrated).select {|v| v < version}
+        inserting = (versions - migrated).select { |v| v < version }
         if inserting.any?
-          if (duplicate = inserting.detect {|v| inserting.count(v) > 1})
+          if (duplicate = inserting.detect { |v| inserting.count(v) > 1 })
             raise "Duplicate migration #{duplicate}. Please renumber your migrations to resolve the conflict."
           end
-          execute insert_versions_sql(inserting)
+          if supports_multi_insert?
+            execute insert_versions_sql(inserting)
+          else
+            inserting.each do |v|
+              execute insert_versions_sql(v)
+            end
+          end
         end
       end
 
-      def type_to_sql(type, limit = nil, precision = nil, scale = nil) #:nodoc:
-        if native = native_database_types[type.to_sym]
+      def type_to_sql(type, limit: nil, precision: nil, scale: nil, **) # :nodoc:
+        type = type.to_sym if type
+        if native = native_database_types[type]
           column_type_sql = (native.is_a?(Hash) ? native[:name] : native).dup
 
           if type == :decimal # ignore limit, use precision and scale
@@ -1064,7 +1090,7 @@ module ActiveRecord
               raise ArgumentError, "Error adding decimal column: precision cannot be empty if scale is specified"
             end
 
-          elsif [:datetime, :time].include?(type) && precision ||= native[:precision]
+          elsif [:datetime, :timestamp, :time, :interval].include?(type) && precision ||= native[:precision]
             if (0..6) === precision
               column_type_sql << "(#{precision})"
             else
@@ -1081,7 +1107,7 @@ module ActiveRecord
       end
 
       # Given a set of columns and an ORDER BY clause, returns the columns for a SELECT DISTINCT.
-      # PostgreSQL, MySQL, and Oracle overrides this for custom DISTINCT syntax - they
+      # PostgreSQL, MySQL, and Oracle override this for custom DISTINCT syntax - they
       # require the order columns appear in the SELECT.
       #
       #   columns_for_distinct("posts.id", ["posts.created_at desc"])
@@ -1116,18 +1142,14 @@ module ActiveRecord
       end
 
       def add_index_options(table_name, column_name, comment: nil, **options) # :nodoc:
-        if column_name.is_a?(String) && /\W/ === column_name
-          column_names = column_name
-        else
-          column_names = Array(column_name)
-        end
+        column_names = index_column_names(column_name)
 
-        options.assert_valid_keys(:unique, :order, :name, :where, :length, :internal, :using, :algorithm, :type)
+        options.assert_valid_keys(:unique, :order, :name, :where, :length, :internal, :using, :algorithm, :type, :opclass)
 
         index_type = options[:type].to_s if options.key?(:type)
         index_type ||= options[:unique] ? "UNIQUE" : ""
         index_name = options[:name].to_s if options.key?(:name)
-        index_name ||= index_name(table_name, index_name_options(column_names))
+        index_name ||= index_name(table_name, column_names)
 
         if options.key?(:algorithm)
           algorithm = index_algorithms.fetch(options[:algorithm]) {
@@ -1143,7 +1165,7 @@ module ActiveRecord
 
         validate_index_length!(table_name, index_name, options.fetch(:internal, false))
 
-        if data_source_exists?(table_name) && index_name_exists?(table_name, index_name, false)
+        if data_source_exists?(table_name) && index_name_exists?(table_name, index_name)
           raise ArgumentError, "Index name '#{index_name}' on table '#{table_name}' already exists"
         end
         index_columns = quoted_columns_for_index(column_names, options).join(", ")
@@ -1161,59 +1183,68 @@ module ActiveRecord
       end
 
       # Changes the comment for a column or removes it if +nil+.
-      def change_column_comment(table_name, column_name, comment) #:nodoc:
+      def change_column_comment(table_name, column_name, comment)
         raise NotImplementedError, "#{self.class} does not support changing column comments"
       end
 
-      protected
-        def add_index_sort_order(option_strings, column_names, options = {})
-          if options.is_a?(Hash) && order = options[:order]
-            case order
-            when Hash
-              column_names.each {|name| option_strings[name] += " #{order[name].upcase}" if order.has_key?(name)}
-            when String
-              column_names.each {|name| option_strings[name] += " #{order.upcase}"}
-            end
-          end
+      def create_schema_dumper(options) # :nodoc:
+        SchemaDumper.create(self, options)
+      end
 
-          return option_strings
+      private
+        def column_options_keys
+          [:limit, :precision, :scale, :default, :null, :collation, :comment]
         end
 
-        # Overridden by the MySQL adapter for supporting index lengths
-        def quoted_columns_for_index(column_names, options = {})
-          return [column_names] if column_names.is_a?(String)
+        def add_index_sort_order(quoted_columns, **options)
+          orders = options_for_index_columns(options[:order])
+          quoted_columns.each do |name, column|
+            column << " #{orders[name].upcase}" if orders[name].present?
+          end
+        end
 
-          option_strings = Hash[column_names.map {|name| [name, '']}]
+        def options_for_index_columns(options)
+          if options.is_a?(Hash)
+            options.symbolize_keys
+          else
+            Hash.new { |hash, column| hash[column] = options }
+          end
+        end
 
-          # add index sort order if supported
+        # Overridden by the MySQL adapter for supporting index lengths and by
+        # the PostgreSQL adapter for supporting operator classes.
+        def add_options_for_index_columns(quoted_columns, **options)
           if supports_index_sort_order?
-            option_strings = add_index_sort_order(option_strings, column_names, options)
+            quoted_columns = add_index_sort_order(quoted_columns, options)
           end
 
-          column_names.map {|name| quote_column_name(name) + option_strings[name]}
+          quoted_columns
+        end
+
+        def quoted_columns_for_index(column_names, **options)
+          return [column_names] if column_names.is_a?(String)
+
+          quoted_columns = Hash[column_names.map { |name| [name.to_sym, quote_column_name(name).dup] }]
+          add_options_for_index_columns(quoted_columns, options).values
         end
 
         def index_name_for_remove(table_name, options = {})
           return options[:name] if can_remove_index_by_name?(options)
 
-          # if the adapter doesn't support the indexes call the best we can do
-          # is return the default index name for the options provided
-          return index_name(table_name, options) unless respond_to?(:indexes)
-
           checks = []
 
           if options.is_a?(Hash)
             checks << lambda { |i| i.name == options[:name].to_s } if options.key?(:name)
-            column_names = Array(options[:column]).map(&:to_s)
+            column_names = index_column_names(options[:column])
           else
-            column_names = Array(options).map(&:to_s)
+            column_names = index_column_names(options)
           end
 
-          if column_names.any?
-            checks << lambda { |i| i.columns.join('_and_') == column_names.join('_and_') }
+          if column_names.present?
+            checks << lambda { |i| index_name(table_name, i.columns) == index_name(table_name, column_names) }
           end
 
-          raise ArgumentError "No name or columns specified" if checks.none?
+          raise ArgumentError, "No name or columns specified" if checks.none?
 
           matching_indexes = indexes(table_name).select { |i| checks.all? { |check| check[i] } }
 
@@ -1249,50 +1280,126 @@ module ActiveRecord
           end
         end
 
-      private
-      def create_table_definition(*args)
-        TableDefinition.new(*args)
-      end
+        def schema_creation
+          SchemaCreation.new(self)
+        end
 
-      def create_alter_table(name)
-        AlterTable.new create_table_definition(name)
-      end
+        def create_table_definition(*args)
+          TableDefinition.new(*args)
+        end
 
-      def index_name_options(column_names) # :nodoc:
-        if column_names.is_a?(String)
-          column_names = column_names.scan(/\w+/).join('_')
+        def create_alter_table(name)
+          AlterTable.new create_table_definition(name)
         end
 
-        { column: column_names }
-      end
+        def fetch_type_metadata(sql_type)
+          cast_type = lookup_cast_type(sql_type)
+          SqlTypeMetadata.new(
+            sql_type: sql_type,
+            type: cast_type.type,
+            limit: cast_type.limit,
+            precision: cast_type.precision,
+            scale: cast_type.scale,
+          )
+        end
 
-      def foreign_key_name(table_name, options) # :nodoc:
-        identifier = "#{table_name}_#{options.fetch(:column)}_fk"
-        hashed_identifier = Digest::SHA256.hexdigest(identifier).first(10)
-        options.fetch(:name) do
-          "fk_rails_#{hashed_identifier}"
+        def index_column_names(column_names)
+          if column_names.is_a?(String) && /\W/.match?(column_names)
+            column_names
+          else
+            Array(column_names)
+          end
         end
-      end
 
-      def validate_index_length!(table_name, new_name, internal = false) # :nodoc:
-        max_index_length = internal ? index_name_length : allowed_index_name_length
+        def index_name_options(column_names)
+          if column_names.is_a?(String) && /\W/.match?(column_names)
+            column_names = column_names.scan(/\w+/).join("_")
+          end
 
-        if new_name.length > max_index_length
-          raise ArgumentError, "Index name '#{new_name}' on table '#{table_name}' is too long; the limit is #{allowed_index_name_length} characters"
+          { column: column_names }
         end
-      end
 
-      def extract_new_default_value(default_or_changes)
-        if default_or_changes.is_a?(Hash) && default_or_changes.has_key?(:from) && default_or_changes.has_key?(:to)
-          default_or_changes[:to]
-        else
-          default_or_changes
+        def foreign_key_name(table_name, options)
+          options.fetch(:name) do
+            identifier = "#{table_name}_#{options.fetch(:column)}_fk"
+            hashed_identifier = Digest::SHA256.hexdigest(identifier).first(10)
+
+            "fk_rails_#{hashed_identifier}"
+          end
         end
-      end
 
-      def can_remove_index_by_name?(options)
-        options.is_a?(Hash) && options.key?(:name) && options.except(:name, :algorithm).empty?
-      end
+        def foreign_key_for(from_table, options_or_to_table = {})
+          return unless supports_foreign_keys?
+          foreign_keys(from_table).detect { |fk| fk.defined_for? options_or_to_table }
+        end
+
+        def foreign_key_for!(from_table, options_or_to_table = {})
+          foreign_key_for(from_table, options_or_to_table) || \
+            raise(ArgumentError, "Table '#{from_table}' has no foreign key for #{options_or_to_table}")
+        end
+
+        def extract_foreign_key_action(specifier)
+          case specifier
+          when "CASCADE"; :cascade
+          when "SET NULL"; :nullify
+          when "RESTRICT"; :restrict
+          end
+        end
+
+        def validate_index_length!(table_name, new_name, internal = false)
+          max_index_length = internal ? index_name_length : allowed_index_name_length
+
+          if new_name.length > max_index_length
+            raise ArgumentError, "Index name '#{new_name}' on table '#{table_name}' is too long; the limit is #{allowed_index_name_length} characters"
+          end
+        end
+
+        def extract_new_default_value(default_or_changes)
+          if default_or_changes.is_a?(Hash) && default_or_changes.has_key?(:from) && default_or_changes.has_key?(:to)
+            default_or_changes[:to]
+          else
+            default_or_changes
+          end
+        end
+
+        def can_remove_index_by_name?(options)
+          options.is_a?(Hash) && options.key?(:name) && options.except(:name, :algorithm).empty?
+        end
+
+        def add_column_for_alter(table_name, column_name, type, options = {})
+          td = create_table_definition(table_name)
+          cd = td.new_column_definition(column_name, type, options)
+          schema_creation.accept(AddColumnDefinition.new(cd))
+        end
+
+        def remove_column_for_alter(table_name, column_name, type = nil, options = {})
+          "DROP COLUMN #{quote_column_name(column_name)}"
+        end
+
+        def remove_columns_for_alter(table_name, *column_names)
+          column_names.map { |column_name| remove_column_for_alter(table_name, column_name) }
+        end
+
+        def insert_versions_sql(versions)
+          sm_table = quote_table_name(ActiveRecord::SchemaMigration.table_name)
+
+          if versions.is_a?(Array)
+            sql = "INSERT INTO #{sm_table} (version) VALUES\n".dup
+            sql << versions.map { |v| "(#{quote(v)})" }.join(",\n")
+            sql << ";\n\n"
+            sql
+          else
+            "INSERT INTO #{sm_table} (version) VALUES (#{quote(versions)});"
+          end
+        end
+
+        def data_source_sql(name = nil, type: nil)
+          raise NotImplementedError
+        end
+
+        def quoted_scope(name = nil, type: nil)
+          raise NotImplementedError
+        end
     end
   end
 end
diff --git a/activerecord/lib/active_record/connection_adapters/abstract/transaction.rb b/activerecord/lib/active_record/connection_adapters/abstract/transaction.rb
index ca795cb1ad..d9ac8db6a8 100644
--- a/activerecord/lib/active_record/connection_adapters/abstract/transaction.rb
+++ b/activerecord/lib/active_record/connection_adapters/abstract/transaction.rb
@@ -1,10 +1,15 @@
+# frozen_string_literal: true
+
 module ActiveRecord
   module ConnectionAdapters
     class TransactionState
-      VALID_STATES = Set.new([:committed, :rolledback, nil])
-
       def initialize(state = nil)
         @state = state
+        @children = []
+      end
+
+      def add_child(state)
+        @children << state
       end
 
       def finalized?
@@ -19,15 +24,43 @@ module ActiveRecord
         @state == :rolledback
       end
 
+      def fully_completed?
+        completed?
+      end
+
       def completed?
         committed? || rolledback?
       end
 
       def set_state(state)
-        unless VALID_STATES.include?(state)
+        ActiveSupport::Deprecation.warn(<<-MSG.squish)
+          The set_state method is deprecated and will be removed in
+          Rails 6.0. Please use rollback! or commit! to set transaction
+          state directly.
+        MSG
+        case state
+        when :rolledback
+          rollback!
+        when :committed
+          commit!
+        when nil
+          nullify!
+        else
           raise ArgumentError, "Invalid transaction state: #{state}"
         end
-        @state = state
+      end
+
+      def rollback!
+        @children.each { |c| c.rollback! }
+        @state = :rolledback
+      end
+
+      def commit!
+        @state = :committed
+      end
+
+      def nullify!
+        @state = nil
       end
     end
 
@@ -41,7 +74,6 @@ module ActiveRecord
     end
 
     class Transaction #:nodoc:
-
       attr_reader :connection, :state, :records, :savepoint_name
       attr_writer :joinable
 
@@ -58,7 +90,7 @@ module ActiveRecord
       end
 
       def rollback
-        @state.set_state(:rolledback)
+        @state.rollback!
       end
 
       def rollback_records
@@ -73,7 +105,7 @@ module ActiveRecord
       end
 
       def commit
-        @state.set_state(:committed)
+        @state.commit!
       end
 
       def before_commit_records
@@ -101,9 +133,11 @@ module ActiveRecord
     end
 
     class SavepointTransaction < Transaction
-
-      def initialize(connection, savepoint_name, options, *args)
+      def initialize(connection, savepoint_name, parent_transaction, options, *args)
         super(connection, options, *args)
+
+        parent_transaction.state.add_child(@state)
+
         if options[:isolation]
           raise ActiveRecord::TransactionIsolationError, "cannot set transaction isolation in a nested transaction"
         end
@@ -124,7 +158,6 @@ module ActiveRecord
     end
 
     class RealTransaction < Transaction
-
       def initialize(connection, options, *args)
         super
         if options[:isolation]
@@ -152,57 +185,67 @@ module ActiveRecord
       end
 
       def begin_transaction(options = {})
-        run_commit_callbacks = !current_transaction.joinable?
-        transaction =
-          if @stack.empty?
-            RealTransaction.new(@connection, options, run_commit_callbacks: run_commit_callbacks)
-          else
-            SavepointTransaction.new(@connection, "active_record_#{@stack.size}", options,
-                                     run_commit_callbacks: run_commit_callbacks)
-          end
+        @connection.lock.synchronize do
+          run_commit_callbacks = !current_transaction.joinable?
+          transaction =
+            if @stack.empty?
+              RealTransaction.new(@connection, options, run_commit_callbacks: run_commit_callbacks)
+            else
+              SavepointTransaction.new(@connection, "active_record_#{@stack.size}", @stack.last, options,
+                                       run_commit_callbacks: run_commit_callbacks)
+            end
 
-        @stack.push(transaction)
-        transaction
+          @stack.push(transaction)
+          transaction
+        end
       end
 
       def commit_transaction
-        transaction = @stack.last
+        @connection.lock.synchronize do
+          transaction = @stack.last
 
-        begin
-          transaction.before_commit_records
-        ensure
-          @stack.pop
-        end
+          begin
+            transaction.before_commit_records
+          ensure
+            @stack.pop
+          end
 
-        transaction.commit
-        transaction.commit_records
+          transaction.commit
+          transaction.commit_records
+        end
       end
 
       def rollback_transaction(transaction = nil)
-        transaction ||= @stack.pop
-        transaction.rollback
-        transaction.rollback_records
+        @connection.lock.synchronize do
+          transaction ||= @stack.pop
+          transaction.rollback
+          transaction.rollback_records
+        end
       end
 
       def within_new_transaction(options = {})
-        transaction = begin_transaction options
-        yield
-      rescue Exception => error
-        if transaction
-          rollback_transaction
-          after_failure_actions(transaction, error)
-        end
-        raise
-      ensure
-        unless error
-          if Thread.current.status == 'aborting'
-            rollback_transaction if transaction
-          else
-            begin
-              commit_transaction
-            rescue Exception
-              rollback_transaction(transaction) unless transaction.state.completed?
-              raise
+        @connection.lock.synchronize do
+          begin
+            transaction = begin_transaction options
+            yield
+          rescue Exception => error
+            if transaction
+              rollback_transaction
+              after_failure_actions(transaction, error)
+            end
+            raise
+          ensure
+            unless error
+              if Thread.current.status == "aborting"
+                rollback_transaction if transaction
+              else
+                begin
+                  commit_transaction if transaction
+                rescue Exception
+                  rollback_transaction(transaction) unless transaction.state.completed?
+                  raise
+                end
+              end
             end
           end
         end
@@ -226,7 +269,6 @@ module ActiveRecord
           return unless error.is_a?(ActiveRecord::PreparedStatementCacheExpired)
           @connection.clear_cache!
         end
-
     end
   end
 end
diff --git a/activerecord/lib/active_record/connection_adapters/abstract_adapter.rb b/activerecord/lib/active_record/connection_adapters/abstract_adapter.rb
index d4b9e301bc..fc80d332f9 100644
--- a/activerecord/lib/active_record/connection_adapters/abstract_adapter.rb
+++ b/activerecord/lib/active_record/connection_adapters/abstract_adapter.rb
@@ -1,11 +1,15 @@
-require 'active_record/type'
-require 'active_record/connection_adapters/determine_if_preparable_visitor'
-require 'active_record/connection_adapters/schema_cache'
-require 'active_record/connection_adapters/sql_type_metadata'
-require 'active_record/connection_adapters/abstract/schema_dumper'
-require 'active_record/connection_adapters/abstract/schema_creation'
-require 'arel/collectors/bind'
-require 'arel/collectors/sql_string'
+# frozen_string_literal: true
+
+require "active_record/connection_adapters/determine_if_preparable_visitor"
+require "active_record/connection_adapters/schema_cache"
+require "active_record/connection_adapters/sql_type_metadata"
+require "active_record/connection_adapters/abstract/schema_dumper"
+require "active_record/connection_adapters/abstract/schema_creation"
+require "active_support/concurrency/load_interlock_aware_monitor"
+require "arel/collectors/bind"
+require "arel/collectors/composite"
+require "arel/collectors/sql_string"
+require "arel/collectors/substitute_binds"
 
 module ActiveRecord
   module ConnectionAdapters # :nodoc:
@@ -14,7 +18,7 @@ module ActiveRecord
     autoload :Column
     autoload :ConnectionSpecification
 
-    autoload_at 'active_record/connection_adapters/abstract/schema_definitions' do
+    autoload_at "active_record/connection_adapters/abstract/schema_definitions" do
       autoload :IndexDefinition
       autoload :ColumnDefinition
       autoload :ChangeColumnDefinition
@@ -25,11 +29,11 @@ module ActiveRecord
       autoload :ReferenceDefinition
     end
 
-    autoload_at 'active_record/connection_adapters/abstract/connection_pool' do
+    autoload_at "active_record/connection_adapters/abstract/connection_pool" do
       autoload :ConnectionHandler
     end
 
-    autoload_under 'abstract' do
+    autoload_under "abstract" do
       autoload :SchemaStatements
       autoload :DatabaseStatements
       autoload :DatabaseLimits
@@ -39,7 +43,7 @@ module ActiveRecord
       autoload :Savepoints
     end
 
-    autoload_at 'active_record/connection_adapters/abstract/transaction' do
+    autoload_at "active_record/connection_adapters/abstract/transaction" do
       autoload :TransactionManager
       autoload :NullTransaction
       autoload :RealTransaction
@@ -61,20 +65,19 @@ module ActiveRecord
     # Most of the methods in the adapter are useful during migrations. Most
     # notably, the instance methods provided by SchemaStatements are very useful.
     class AbstractAdapter
-      ADAPTER_NAME = 'Abstract'.freeze
+      ADAPTER_NAME = "Abstract".freeze
+      include ActiveSupport::Callbacks
+      define_callbacks :checkout, :checkin
+
       include Quoting, DatabaseStatements, SchemaStatements
       include DatabaseLimits
       include QueryCache
-      include ActiveSupport::Callbacks
-      include ColumnDumper
       include Savepoints
 
       SIMPLE_INT = /\A\d+\z/
 
-      define_callbacks :checkout, :checkin
-
       attr_accessor :visitor, :pool
-      attr_reader :schema_cache, :owner, :logger
+      attr_reader :schema_cache, :owner, :logger, :prepared_statements, :lock
       alias :in_use? :owner
 
       def self.type_cast_config_to_integer(config)
@@ -93,8 +96,6 @@ module ActiveRecord
         end
       end
 
-      attr_reader :prepared_statements
-
       def initialize(connection, logger = nil, config = {}) # :nodoc:
         super()
 
@@ -104,9 +105,11 @@ module ActiveRecord
         @logger              = logger
         @config              = config
         @pool                = nil
+        @idle_since          = Concurrent.monotonic_time
         @schema_cache        = SchemaCache.new self
         @quoted_column_names, @quoted_table_names = {}, {}
-        @visitor             = arel_visitor
+        @visitor = arel_visitor
+        @lock = ActiveSupport::Concurrency::LoadInterlockAwareMonitor.new
 
         if self.class.type_cast_config_to_boolean(config.fetch(:prepared_statements) { true })
           @prepared_statements = true
@@ -120,55 +123,26 @@ module ActiveRecord
         include Comparable
 
         def initialize(version_string)
-          @version = version_string.split('.').map(&:to_i)
+          @version = version_string.split(".").map(&:to_i)
         end
 
         def <=>(version_string)
-          @version <=> version_string.split('.').map(&:to_i)
-        end
-      end
-
-      class BindCollector < Arel::Collectors::Bind
-        def compile(bvs, conn)
-          casted_binds = conn.prepare_binds_for_database(bvs)
-          super(casted_binds.map { |value| conn.quote(value) })
-        end
-      end
-
-      class SQLString < Arel::Collectors::SQLString
-        def compile(bvs, conn)
-          super(bvs)
-        end
-      end
-
-      def collector
-        if prepared_statements
-          SQLString.new
-        else
-          BindCollector.new
+          @version <=> version_string.split(".").map(&:to_i)
         end
       end
 
-      def arel_visitor # :nodoc:
-        Arel::Visitors::ToSql.new(self)
-      end
-
-      def valid_type?(type)
-        false
-      end
-
-      def schema_creation
-        SchemaCreation.new self
+      def valid_type?(type) # :nodoc:
+        !native_database_types[type].nil?
       end
 
       # this method must only be called while holding connection pool's mutex
       def lease
         if in_use?
-          msg = 'Cannot lease connection, '
+          msg = "Cannot lease connection, ".dup
           if @owner == Thread.current
-            msg << 'it is already leased by the current thread.'
+            msg << "it is already leased by the current thread."
           else
-            msg << "it is already in use by a different thread: #{@owner}. " <<
+            msg << "it is already in use by a different thread: #{@owner}. " \
                    "Current thread: #{Thread.current}."
           end
           raise ActiveRecordError, msg
@@ -184,7 +158,37 @@ module ActiveRecord
 
       # this method must only be called while holding connection pool's mutex
       def expire
-        @owner = nil
+        if in_use?
+          if @owner != Thread.current
+            raise ActiveRecordError, "Cannot expire connection, " \
+              "it is owned by a different thread: #{@owner}. " \
+              "Current thread: #{Thread.current}."
+          end
+
+          @idle_since = Concurrent.monotonic_time
+          @owner = nil
+        else
+          raise ActiveRecordError, "Cannot expire connection, it is not currently leased."
+        end
+      end
+
+      # this method must only be called while holding connection pool's mutex (and a desire for segfaults)
+      def steal! # :nodoc:
+        if in_use?
+          if @owner != Thread.current
+            pool.send :remove_connection_from_thread_cache, self, @owner
+
+            @owner = Thread.current
+          end
+        else
+          raise ActiveRecordError, "Cannot steal connection, it is not currently leased."
+        end
+      end
+
+      # Seconds since this connection was returned to the pool
+      def seconds_idle # :nodoc:
+        return 0 if in_use?
+        Concurrent.monotonic_time - @idle_since
       end
 
       def unprepared_statement
@@ -200,17 +204,6 @@ module ActiveRecord
         self.class::ADAPTER_NAME
       end
 
-      # Does this adapter support migrations?
-      def supports_migrations?
-        false
-      end
-
-      # Can this adapter determine the primary key for tables not attached
-      # to an Active Record class, such as join tables?
-      def supports_primary_key?
-        false
-      end
-
       # Does this adapter support DDL rollbacks in transactions? That is, would
       # CREATE TABLE or ALTER TABLE get rolled back by a transaction?
       def supports_ddl_transactions?
@@ -279,6 +272,17 @@ module ActiveRecord
         false
       end
 
+      # Does this adapter support creating invalid constraints?
+      def supports_validate_constraints?
+        false
+      end
+
+      # Does this adapter support creating foreign key constraints
+      # in the same statement as creating the table?
+      def supports_foreign_keys_in_create?
+        supports_foreign_keys?
+      end
+
       # Does this adapter support views?
       def supports_views?
         false
@@ -309,6 +313,11 @@ module ActiveRecord
         true
       end
 
+      # Does this adapter support virtual columns?
+      def supports_virtual_columns?
+        false
+      end
+
       # This is meant to be implemented by the adapters that support extensions
       def disable_extension(name)
       end
@@ -371,6 +380,19 @@ module ActiveRecord
         reset_transaction
       end
 
+      # Immediately forget this connection ever existed. Unlike disconnect!,
+      # this will not communicate with the server.
+      #
+      # After calling this method, the behavior of all other methods becomes
+      # undefined. This is called internally just before a forked process gets
+      # rid of a connection that belonged to its parent.
+      def discard!
+        # This should be overridden by concrete adapters.
+        #
+        # Prevent @connection's finalizer from touching the socket, or
+        # otherwise communicating with its server, when it is collected.
+      end
+
       # Reset the state of this connection, directing the DBMS to clear
       # transactions and other connection-related server-side state. Usually a
       # database-dependent operation.
@@ -396,13 +418,13 @@ module ActiveRecord
       # Checks whether the connection to the database is still active (i.e. not stale).
       # This is done under the hood by calling #active?. If the connection
       # is no longer active, then this method will reconnect to the database.
-      def verify!(*ignored)
+      def verify!
         reconnect! unless active?
       end
 
       # Provides access to the underlying database driver for this adapter. For
       # example, this method returns a Mysql2::Client object in case of Mysql2Adapter,
-      # and a PGconn object in case of PostgreSQLAdapter.
+      # and a PG::Connection object in case of PostgreSQLAdapter.
       #
       # This is useful for when you need to call a proprietary method such as
       # PostgreSQL's lo_* methods.
@@ -410,19 +432,15 @@ module ActiveRecord
         @connection
       end
 
-      def case_sensitive_comparison(table, attribute, column, value)
-        if value.nil?
-          table[attribute].eq(value)
-        else
-          table[attribute].eq(Arel::Nodes::BindParam.new)
-        end
+      def case_sensitive_comparison(table, attribute, column, value) # :nodoc:
+        table[attribute].eq(value)
       end
 
-      def case_insensitive_comparison(table, attribute, column, value)
+      def case_insensitive_comparison(table, attribute, column, value) # :nodoc:
         if can_perform_case_insensitive_comparison_for?(column)
-          table[attribute].lower.eq(table.lower(Arel::Nodes::BindParam.new))
+          table[attribute].lower.eq(table.lower(value))
         else
-          table[attribute].eq(Arel::Nodes::BindParam.new)
+          table[attribute].eq(value)
         end
       end
 
@@ -436,152 +454,165 @@ module ActiveRecord
         pool.checkin self
       end
 
-      def type_map # :nodoc:
-        @type_map ||= Type::TypeMap.new.tap do |mapping|
-          initialize_type_map(mapping)
-        end
+      def column_name_for_operation(operation, node) # :nodoc:
+        column_name_from_arel_node(node)
       end
 
-      def new_column(name, default, sql_type_metadata, null, table_name, default_function = nil, collation = nil) # :nodoc:
-        Column.new(name, default, sql_type_metadata, null, table_name, default_function, collation)
+      def column_name_from_arel_node(node) # :nodoc:
+        visitor.accept(node, Arel::Collectors::SQLString.new).value
       end
 
-      def lookup_cast_type(sql_type) # :nodoc:
-        type_map.lookup(sql_type)
+      def default_index_type?(index) # :nodoc:
+        index.using.nil?
       end
 
-      def column_name_for_operation(operation, node) # :nodoc:
-        visitor.accept(node, collector).value
-      end
-
-      def combine_bind_parameters(
-        from_clause: [],
-        join_clause: [],
-        where_clause: [],
-        having_clause: [],
-        limit: nil,
-        offset: nil
-      ) # :nodoc:
-        result = from_clause + join_clause + where_clause + having_clause
-        if limit
-          result << limit
-        end
-        if offset
-          result << offset
+      private
+        def type_map
+          @type_map ||= Type::TypeMap.new.tap do |mapping|
+            initialize_type_map(mapping)
+          end
         end
-        result
-      end
-
-      protected
-
-      def initialize_type_map(m) # :nodoc:
-        register_class_with_limit m, %r(boolean)i,       Type::Boolean
-        register_class_with_limit m, %r(char)i,          Type::String
-        register_class_with_limit m, %r(binary)i,        Type::Binary
-        register_class_with_limit m, %r(text)i,          Type::Text
-        register_class_with_precision m, %r(date)i,      Type::Date
-        register_class_with_precision m, %r(time)i,      Type::Time
-        register_class_with_precision m, %r(datetime)i,  Type::DateTime
-        register_class_with_limit m, %r(float)i,         Type::Float
-        register_class_with_limit m, %r(int)i,           Type::Integer
-
-        m.alias_type %r(blob)i,      'binary'
-        m.alias_type %r(clob)i,      'text'
-        m.alias_type %r(timestamp)i, 'datetime'
-        m.alias_type %r(numeric)i,   'decimal'
-        m.alias_type %r(number)i,    'decimal'
-        m.alias_type %r(double)i,    'float'
-
-        m.register_type(%r(decimal)i) do |sql_type|
-          scale = extract_scale(sql_type)
-          precision = extract_precision(sql_type)
-
-          if scale == 0
-            # FIXME: Remove this class as well
-            Type::DecimalWithoutScale.new(precision: precision)
-          else
-            Type::Decimal.new(precision: precision, scale: scale)
+
+        def initialize_type_map(m = type_map)
+          register_class_with_limit m, %r(boolean)i,       Type::Boolean
+          register_class_with_limit m, %r(char)i,          Type::String
+          register_class_with_limit m, %r(binary)i,        Type::Binary
+          register_class_with_limit m, %r(text)i,          Type::Text
+          register_class_with_precision m, %r(date)i,      Type::Date
+          register_class_with_precision m, %r(time)i,      Type::Time
+          register_class_with_precision m, %r(datetime)i,  Type::DateTime
+          register_class_with_limit m, %r(float)i,         Type::Float
+          register_class_with_limit m, %r(int)i,           Type::Integer
+
+          m.alias_type %r(blob)i,      "binary"
+          m.alias_type %r(clob)i,      "text"
+          m.alias_type %r(timestamp)i, "datetime"
+          m.alias_type %r(numeric)i,   "decimal"
+          m.alias_type %r(number)i,    "decimal"
+          m.alias_type %r(double)i,    "float"
+
+          m.register_type %r(^json)i, Type::Json.new
+
+          m.register_type(%r(decimal)i) do |sql_type|
+            scale = extract_scale(sql_type)
+            precision = extract_precision(sql_type)
+
+            if scale == 0
+              # FIXME: Remove this class as well
+              Type::DecimalWithoutScale.new(precision: precision)
+            else
+              Type::Decimal.new(precision: precision, scale: scale)
+            end
           end
         end
-      end
 
-      def reload_type_map # :nodoc:
-        type_map.clear
-        initialize_type_map(type_map)
-      end
+        def reload_type_map
+          type_map.clear
+          initialize_type_map
+        end
 
-      def register_class_with_limit(mapping, key, klass) # :nodoc:
-        mapping.register_type(key) do |*args|
-          limit = extract_limit(args.last)
-          klass.new(limit: limit)
+        def register_class_with_limit(mapping, key, klass)
+          mapping.register_type(key) do |*args|
+            limit = extract_limit(args.last)
+            klass.new(limit: limit)
+          end
         end
-      end
 
-      def register_class_with_precision(mapping, key, klass) # :nodoc:
-        mapping.register_type(key) do |*args|
-          precision = extract_precision(args.last)
-          klass.new(precision: precision)
+        def register_class_with_precision(mapping, key, klass)
+          mapping.register_type(key) do |*args|
+            precision = extract_precision(args.last)
+            klass.new(precision: precision)
+          end
         end
-      end
 
-      def extract_scale(sql_type) # :nodoc:
-        case sql_type
+        def extract_scale(sql_type)
+          case sql_type
           when /\((\d+)\)/ then 0
           when /\((\d+)(,(\d+))\)/ then $3.to_i
+          end
         end
-      end
 
-      def extract_precision(sql_type) # :nodoc:
-        $1.to_i if sql_type =~ /\((\d+)(,\d+)?\)/
-      end
+        def extract_precision(sql_type)
+          $1.to_i if sql_type =~ /\((\d+)(,\d+)?\)/
+        end
 
-      def extract_limit(sql_type) # :nodoc:
-        case sql_type
-        when /^bigint/i
-          8
-        when /\((.*)\)/
-          $1.to_i
+        def extract_limit(sql_type)
+          case sql_type
+          when /^bigint/i
+            8
+          when /\((.*)\)/
+            $1.to_i
+          end
         end
-      end
 
-      def translate_exception_class(e, sql)
-        begin
-          message = "#{e.class.name}: #{e.message}: #{sql}"
-        rescue Encoding::CompatibilityError
-          message = "#{e.class.name}: #{e.message.force_encoding sql.encoding}: #{sql}"
+        def translate_exception_class(e, sql)
+          begin
+            message = "#{e.class.name}: #{e.message}: #{sql}"
+          rescue Encoding::CompatibilityError
+            message = "#{e.class.name}: #{e.message.force_encoding sql.encoding}: #{sql}"
+          end
+
+          exception = translate_exception(e, message)
+          exception.set_backtrace e.backtrace
+          exception
         end
 
-        exception = translate_exception(e, message)
-        exception.set_backtrace e.backtrace
-        exception
-      end
+        def log(sql, name = "SQL", binds = [], type_casted_binds = [], statement_name = nil) # :doc:
+          @instrumenter.instrument(
+            "sql.active_record",
+            sql:               sql,
+            name:              name,
+            binds:             binds,
+            type_casted_binds: type_casted_binds,
+            statement_name:    statement_name,
+            connection_id:     object_id) do
+            begin
+              @lock.synchronize do
+                yield
+              end
+            rescue => e
+              raise translate_exception_class(e, sql)
+            end
+          end
+        end
 
-      def log(sql, name = "SQL", binds = [], statement_name = nil)
-        @instrumenter.instrument(
-          "sql.active_record",
-          :sql            => sql,
-          :name           => name,
-          :connection_id  => object_id,
-          :statement_name => statement_name,
-          :binds          => binds) { yield }
-      rescue => e
-        raise translate_exception_class(e, sql)
-      end
+        def translate_exception(exception, message)
+          # override in derived class
+          case exception
+          when RuntimeError
+            exception
+          else
+            ActiveRecord::StatementInvalid.new(message)
+          end
+        end
 
-      def translate_exception(exception, message)
-        # override in derived class
-        ActiveRecord::StatementInvalid.new(message)
-      end
+        def without_prepared_statement?(binds)
+          !prepared_statements || binds.empty?
+        end
 
-      def without_prepared_statement?(binds)
-        !prepared_statements || binds.empty?
-      end
+        def column_for(table_name, column_name)
+          column_name = column_name.to_s
+          columns(table_name).detect { |c| c.name == column_name } ||
+            raise(ActiveRecordError, "No such column: #{table_name}.#{column_name}")
+        end
 
-      def column_for(table_name, column_name) # :nodoc:
-        column_name = column_name.to_s
-        columns(table_name).detect { |c| c.name == column_name } ||
-          raise(ActiveRecordError, "No such column: #{table_name}.#{column_name}")
-      end
+        def collector
+          if prepared_statements
+            Arel::Collectors::Composite.new(
+              Arel::Collectors::SQLString.new,
+              Arel::Collectors::Bind.new,
+            )
+          else
+            Arel::Collectors::SubstituteBinds.new(
+              self,
+              Arel::Collectors::SQLString.new,
+            )
+          end
+        end
+
+        def arel_visitor
+          Arel::Visitors::ToSql.new(self)
+        end
     end
   end
 end
diff --git a/activerecord/lib/active_record/connection_adapters/abstract_mysql_adapter.rb b/activerecord/lib/active_record/connection_adapters/abstract_mysql_adapter.rb
index 718a6c5b91..0afdd959f5 100644
--- a/activerecord/lib/active_record/connection_adapters/abstract_mysql_adapter.rb
+++ b/activerecord/lib/active_record/connection_adapters/abstract_mysql_adapter.rb
@@ -1,32 +1,23 @@
-require 'active_record/connection_adapters/abstract_adapter'
-require 'active_record/connection_adapters/statement_pool'
-require 'active_record/connection_adapters/mysql/column'
-require 'active_record/connection_adapters/mysql/explain_pretty_printer'
-require 'active_record/connection_adapters/mysql/quoting'
-require 'active_record/connection_adapters/mysql/schema_creation'
-require 'active_record/connection_adapters/mysql/schema_definitions'
-require 'active_record/connection_adapters/mysql/schema_dumper'
-require 'active_record/connection_adapters/mysql/type_metadata'
-
-require 'active_support/core_ext/string/strip'
+# frozen_string_literal: true
+
+require "active_record/connection_adapters/abstract_adapter"
+require "active_record/connection_adapters/statement_pool"
+require "active_record/connection_adapters/mysql/column"
+require "active_record/connection_adapters/mysql/explain_pretty_printer"
+require "active_record/connection_adapters/mysql/quoting"
+require "active_record/connection_adapters/mysql/schema_creation"
+require "active_record/connection_adapters/mysql/schema_definitions"
+require "active_record/connection_adapters/mysql/schema_dumper"
+require "active_record/connection_adapters/mysql/schema_statements"
+require "active_record/connection_adapters/mysql/type_metadata"
+
+require "active_support/core_ext/string/strip"
 
 module ActiveRecord
   module ConnectionAdapters
     class AbstractMysqlAdapter < AbstractAdapter
       include MySQL::Quoting
-      include MySQL::ColumnDumper
-
-      def update_table_definition(table_name, base) # :nodoc:
-        MySQL::Table.new(table_name, base)
-      end
-
-      def schema_creation # :nodoc:
-        MySQL::SchemaCreation.new(self)
-      end
-
-      def arel_visitor # :nodoc:
-        Arel::Visitors::MySQL.new(self)
-      end
+      include MySQL::SchemaStatements
 
       ##
       # :singleton-method:
@@ -35,17 +26,17 @@ module ActiveRecord
       # to your application.rb file:
       #
       #   ActiveRecord::ConnectionAdapters::Mysql2Adapter.emulate_booleans = false
-      class_attribute :emulate_booleans
-      self.emulate_booleans = true
+      class_attribute :emulate_booleans, default: true
 
       NATIVE_DATABASE_TYPES = {
-        primary_key: "int auto_increment PRIMARY KEY",
+        primary_key: "bigint auto_increment PRIMARY KEY",
         string:      { name: "varchar", limit: 255 },
         text:        { name: "text", limit: 65535 },
         integer:     { name: "int", limit: 4 },
-        float:       { name: "float" },
+        float:       { name: "float", limit: 24 },
         decimal:     { name: "decimal" },
         datetime:    { name: "datetime" },
+        timestamp:   { name: "timestamp" },
         time:        { name: "time" },
         date:        { name: "date" },
         binary:      { name: "blob", limit: 65535 },
@@ -53,10 +44,7 @@ module ActiveRecord
         json:        { name: "json" },
       }
 
-      INDEX_TYPES  = [:fulltext, :spatial]
-      INDEX_USINGS = [:btree, :hash]
-
-      class StatementPool < ConnectionAdapters::StatementPool
+      class StatementPool < ConnectionAdapters::StatementPool # :nodoc:
         private def dealloc(stmt)
           stmt[:stmt].close
         end
@@ -67,50 +55,25 @@ module ActiveRecord
 
         @statements = StatementPool.new(self.class.type_cast_config_to_integer(config[:statement_limit]))
 
-        if version < '5.0.0'
-          raise "Your version of MySQL (#{full_version.match(/^\d+\.\d+\.\d+/)[0]}) is too old. Active Record supports MySQL >= 5.0."
+        if version < "5.1.10"
+          raise "Your version of MySQL (#{version_string}) is too old. Active Record supports MySQL >= 5.1.10."
         end
       end
 
-      CHARSETS_OF_4BYTES_MAXLEN = ['utf8mb4', 'utf16', 'utf16le', 'utf32']
-
-      def internal_string_options_for_primary_key # :nodoc:
-        super.tap { |options|
-          options[:collation] = collation.sub(/\A[^_]+/, 'utf8') if CHARSETS_OF_4BYTES_MAXLEN.include?(charset)
-        }
-      end
-
       def version #:nodoc:
-        @version ||= Version.new(full_version.match(/^\d+\.\d+\.\d+/)[0])
+        @version ||= Version.new(version_string)
       end
 
       def mariadb? # :nodoc:
-        full_version =~ /mariadb/i
-      end
-
-      # Returns true, since this connection adapter supports migrations.
-      def supports_migrations?
-        true
-      end
-
-      def supports_primary_key?
-        true
+        /mariadb/i.match?(full_version)
       end
 
       def supports_bulk_alter? #:nodoc:
         true
       end
 
-      # Returns true, since this connection adapter supports prepared statement
-      # caching.
-      def supports_statement_cache?
-        true
-      end
-
-      # Technically MySQL allows to create indexes with the sort order syntax
-      # but at the moment (5.5) it doesn't yet implement them
       def supports_index_sort_order?
-        true
+        !mariadb? && version >= "8.0.1"
       end
 
       def supports_transaction_isolation?
@@ -135,9 +98,17 @@ module ActiveRecord
 
       def supports_datetime_with_precision?
         if mariadb?
-          version >= '5.3.0'
+          version >= "5.3.0"
         else
-          version >= '5.6.4'
+          version >= "5.6.4"
+        end
+      end
+
+      def supports_virtual_columns?
+        if mariadb?
+          version >= "5.2.0"
+        else
+          version >= "5.7.5"
         end
       end
 
@@ -146,11 +117,11 @@ module ActiveRecord
       end
 
       def get_advisory_lock(lock_name, timeout = 0) # :nodoc:
-        select_value("SELECT GET_LOCK(#{quote(lock_name)}, #{timeout})") == 1
+        query_value("SELECT GET_LOCK(#{quote(lock_name.to_s)}, #{timeout})") == 1
       end
 
       def release_advisory_lock(lock_name) # :nodoc:
-        select_value("SELECT RELEASE_LOCK(#{quote(lock_name)})") == 1
+        query_value("SELECT RELEASE_LOCK(#{quote(lock_name.to_s)})") == 1
       end
 
       def native_database_types
@@ -158,7 +129,7 @@ module ActiveRecord
       end
 
       def index_algorithms
-        { default: 'ALGORITHM = DEFAULT', copy: 'ALGORITHM = COPY', inplace: 'ALGORITHM = INPLACE' }
+        { default: "ALGORITHM = DEFAULT".dup, copy: "ALGORITHM = COPY".dup, inplace: "ALGORITHM = INPLACE".dup }
       end
 
       # HELPER METHODS ===========================================
@@ -169,10 +140,6 @@ module ActiveRecord
         raise NotImplementedError
       end
 
-      def new_column(*args) #:nodoc:
-        MySQL::Column.new(*args)
-      end
-
       # Must return the MySQL error number from the exception, if the exception has an
       # error number.
       def error_number(exception) # :nodoc:
@@ -182,7 +149,7 @@ module ActiveRecord
       # REFERENTIAL INTEGRITY ====================================
 
       def disable_referential_integrity #:nodoc:
-        old = select_value("SELECT @@FOREIGN_KEY_CHECKS")
+        old = query_value("SELECT @@FOREIGN_KEY_CHECKS")
 
         begin
           update("SET FOREIGN_KEY_CHECKS = 0")
@@ -207,7 +174,7 @@ module ActiveRecord
       def explain(arel, binds = [])
         sql     = "EXPLAIN #{to_sql(arel, binds)}"
         start   = Time.now
-        result  = exec_query(sql, 'EXPLAIN', binds)
+        result  = exec_query(sql, "EXPLAIN", binds)
         elapsed = Time.now - start
 
         MySQL::ExplainPrettyPrinter.new.pp(result, elapsed)
@@ -215,7 +182,11 @@ module ActiveRecord
 
       # Executes the SQL statement in the context of this connection.
       def execute(sql, name = nil)
-        log(sql, name) { @connection.query(sql) }
+        log(sql, name) do
+          ActiveSupport::Dependencies.interlock.permit_concurrent_loads do
+            @connection.query(sql)
+          end
+        end
       end
 
       # Mysql2Adapter doesn't have to free a result after using it, but we use this method
@@ -293,137 +264,38 @@ module ActiveRecord
       end
 
       def current_database
-        select_value 'SELECT DATABASE() as db'
+        query_value("SELECT database()", "SCHEMA")
       end
 
       # Returns the database character set.
       def charset
-        show_variable 'character_set_database'
+        show_variable "character_set_database"
       end
 
       # Returns the database collation strategy.
       def collation
-        show_variable 'collation_database'
-      end
-
-      def tables(name = nil) # :nodoc:
-        ActiveSupport::Deprecation.warn(<<-MSG.squish)
-          #tables currently returns both tables and views.
-          This behavior is deprecated and will be changed with Rails 5.1 to only return tables.
-          Use #data_sources instead.
-        MSG
-
-        if name
-          ActiveSupport::Deprecation.warn(<<-MSG.squish)
-            Passing arguments to #tables is deprecated without replacement.
-          MSG
-        end
-
-        data_sources
-      end
-
-      def data_sources
-        sql = "SELECT table_name FROM information_schema.tables "
-        sql << "WHERE table_schema = #{quote(@config[:database])}"
-
-        select_values(sql, 'SCHEMA')
+        show_variable "collation_database"
       end
 
       def truncate(table_name, name = nil)
         execute "TRUNCATE TABLE #{quote_table_name(table_name)}", name
       end
 
-      def table_exists?(table_name)
-        # Update lib/active_record/internal_metadata.rb when this gets removed
-        ActiveSupport::Deprecation.warn(<<-MSG.squish)
-          #table_exists? currently checks both tables and views.
-          This behavior is deprecated and will be changed with Rails 5.1 to only check tables.
-          Use #data_source_exists? instead.
-        MSG
-
-        data_source_exists?(table_name)
-      end
-
-      def data_source_exists?(table_name)
-        return false unless table_name.present?
-
-        schema, name = extract_schema_qualified_name(table_name)
-
-        sql = "SELECT table_name FROM information_schema.tables "
-        sql << "WHERE table_schema = #{quote(schema)} AND table_name = #{quote(name)}"
-
-        select_values(sql, 'SCHEMA').any?
-      end
-
-      def views # :nodoc:
-        select_values("SHOW FULL TABLES WHERE table_type = 'VIEW'", 'SCHEMA')
-      end
-
-      def view_exists?(view_name) # :nodoc:
-        return false unless view_name.present?
-
-        schema, name = extract_schema_qualified_name(view_name)
-
-        sql = "SELECT table_name FROM information_schema.tables WHERE table_type = 'VIEW'"
-        sql << " AND table_schema = #{quote(schema)} AND table_name = #{quote(name)}"
-
-        select_values(sql, 'SCHEMA').any?
-      end
-
-      # Returns an array of indexes for the given table.
-      def indexes(table_name, name = nil) #:nodoc:
-        indexes = []
-        current_index = nil
-        execute_and_free("SHOW KEYS FROM #{quote_table_name(table_name)}", 'SCHEMA') do |result|
-          each_hash(result) do |row|
-            if current_index != row[:Key_name]
-              next if row[:Key_name] == 'PRIMARY' # skip the primary key
-              current_index = row[:Key_name]
-
-              mysql_index_type = row[:Index_type].downcase.to_sym
-              index_type  = INDEX_TYPES.include?(mysql_index_type)  ? mysql_index_type : nil
-              index_using = INDEX_USINGS.include?(mysql_index_type) ? mysql_index_type : nil
-              indexes << IndexDefinition.new(row[:Table], row[:Key_name], row[:Non_unique].to_i == 0, [], [], nil, nil, index_type, index_using, row[:Index_comment].presence)
-            end
-
-            indexes.last.columns << row[:Column_name]
-            indexes.last.lengths << row[:Sub_part]
-          end
-        end
-
-        indexes
-      end
-
-      # Returns an array of +Column+ objects for the table specified by +table_name+.
-      def columns(table_name) # :nodoc:
-        table_name = table_name.to_s
-        column_definitions(table_name).map do |field|
-          type_metadata = fetch_type_metadata(field[:Type], field[:Extra])
-          if type_metadata.type == :datetime && field[:Default] == "CURRENT_TIMESTAMP"
-            default, default_function = nil, field[:Default]
-          else
-            default, default_function = field[:Default], nil
-          end
-          new_column(field[:Field], default, type_metadata, field[:Null] == "YES", table_name, default_function, field[:Collation], comment: field[:Comment].presence)
-        end
-      end
-
       def table_comment(table_name) # :nodoc:
-        select_value(<<-SQL.strip_heredoc, 'SCHEMA')
+        scope = quoted_scope(table_name)
+
+        query_value(<<-SQL.strip_heredoc, "SCHEMA").presence
           SELECT table_comment
           FROM information_schema.tables
-          WHERE table_name=#{quote(table_name)}
+          WHERE table_schema = #{scope[:schema]}
+            AND table_name = #{scope[:name]}
         SQL
       end
 
-      def create_table(table_name, **options) #:nodoc:
-        super(table_name, options: 'ENGINE=InnoDB', **options)
-      end
-
       def bulk_change_table(table_name, operations) #:nodoc:
         sqls = operations.flat_map do |command, args|
           table, arguments = args.shift, args
-          method = :"#{command}_sql"
+          method = :"#{command}_for_alter"
 
           if respond_to?(method, true)
             send(method, table, *arguments)
@@ -435,6 +307,11 @@ module ActiveRecord
         execute("ALTER TABLE #{quote_table_name(table_name)} #{sqls}")
       end
 
+      def change_table_comment(table_name, comment) #:nodoc:
+        comment = "" if comment.nil?
+        execute("ALTER TABLE #{quote_table_name(table_name)} COMMENT #{quote(comment)}")
+      end
+
       # Renames a table.
       #
       # Example:
@@ -460,7 +337,6 @@ module ActiveRecord
       # it can be helpful to provide these in a migration's +change+ method so it can be reverted.
       # In that case, +options+ and the block will be used by create_table.
       def drop_table(table_name, options = {})
-        create_table_info_cache.delete(table_name) if create_table_info_cache.key?(table_name)
         execute "DROP#{' TEMPORARY' if options[:temporary]} TABLE#{' IF EXISTS' if options[:if_exists]} #{quote_table_name(table_name)}#{' CASCADE' if options[:force] == :cascade}"
       end
 
@@ -476,113 +352,125 @@ module ActiveRecord
 
       def change_column_default(table_name, column_name, default_or_changes) #:nodoc:
         default = extract_new_default_value(default_or_changes)
-        column = column_for(table_name, column_name)
-        change_column table_name, column_name, column.sql_type, :default => default
+        change_column table_name, column_name, nil, default: default
       end
 
       def change_column_null(table_name, column_name, null, default = nil) #:nodoc:
-        column = column_for(table_name, column_name)
-
         unless null || default.nil?
           execute("UPDATE #{quote_table_name(table_name)} SET #{quote_column_name(column_name)}=#{quote(default)} WHERE #{quote_column_name(column_name)} IS NULL")
         end
 
-        change_column table_name, column_name, column.sql_type, :null => null
+        change_column table_name, column_name, nil, null: null
+      end
+
+      def change_column_comment(table_name, column_name, comment) #:nodoc:
+        change_column table_name, column_name, nil, comment: comment
       end
 
       def change_column(table_name, column_name, type, options = {}) #:nodoc:
-        execute("ALTER TABLE #{quote_table_name(table_name)} #{change_column_sql(table_name, column_name, type, options)}")
+        execute("ALTER TABLE #{quote_table_name(table_name)} #{change_column_for_alter(table_name, column_name, type, options)}")
       end
 
       def rename_column(table_name, column_name, new_column_name) #:nodoc:
-        execute("ALTER TABLE #{quote_table_name(table_name)} #{rename_column_sql(table_name, column_name, new_column_name)}")
+        execute("ALTER TABLE #{quote_table_name(table_name)} #{rename_column_for_alter(table_name, column_name, new_column_name)}")
         rename_column_indexes(table_name, column_name, new_column_name)
       end
 
       def add_index(table_name, column_name, options = {}) #:nodoc:
         index_name, index_type, index_columns, _, index_algorithm, index_using, comment = add_index_options(table_name, column_name, options)
-        sql = "CREATE #{index_type} INDEX #{quote_column_name(index_name)} #{index_using} ON #{quote_table_name(table_name)} (#{index_columns}) #{index_algorithm}"
+        sql = "CREATE #{index_type} INDEX #{quote_column_name(index_name)} #{index_using} ON #{quote_table_name(table_name)} (#{index_columns}) #{index_algorithm}".dup
         execute add_sql_comment!(sql, comment)
       end
 
       def add_sql_comment!(sql, comment) # :nodoc:
-        sql << " COMMENT #{quote(comment)}" if comment
+        sql << " COMMENT #{quote(comment)}" if comment.present?
         sql
       end
 
       def foreign_keys(table_name)
         raise ArgumentError unless table_name.present?
 
-        schema, name = extract_schema_qualified_name(table_name)
-
-        fk_info = select_all <<-SQL.strip_heredoc
-          SELECT fk.referenced_table_name as 'to_table'
-                ,fk.referenced_column_name as 'primary_key'
-                ,fk.column_name as 'column'
-                ,fk.constraint_name as 'name'
-          FROM information_schema.key_column_usage fk
-          WHERE fk.referenced_column_name is not null
-            AND fk.table_schema = #{quote(schema)}
-            AND fk.table_name = #{quote(name)}
+        scope = quoted_scope(table_name)
+
+        fk_info = exec_query(<<-SQL.strip_heredoc, "SCHEMA")
+          SELECT fk.referenced_table_name AS 'to_table',
+                 fk.referenced_column_name AS 'primary_key',
+                 fk.column_name AS 'column',
+                 fk.constraint_name AS 'name',
+                 rc.update_rule AS 'on_update',
+                 rc.delete_rule AS 'on_delete'
+          FROM information_schema.referential_constraints rc
+          JOIN information_schema.key_column_usage fk
+          USING (constraint_schema, constraint_name)
+          WHERE fk.referenced_column_name IS NOT NULL
+            AND fk.table_schema = #{scope[:schema]}
+            AND fk.table_name = #{scope[:name]}
+            AND rc.constraint_schema = #{scope[:schema]}
+            AND rc.table_name = #{scope[:name]}
         SQL
 
-        create_table_info = create_table_info(table_name)
-
         fk_info.map do |row|
           options = {
-            column: row['column'],
-            name: row['name'],
-            primary_key: row['primary_key']
+            column: row["column"],
+            name: row["name"],
+            primary_key: row["primary_key"]
           }
 
-          options[:on_update] = extract_foreign_key_action(create_table_info, row['name'], "UPDATE")
-          options[:on_delete] = extract_foreign_key_action(create_table_info, row['name'], "DELETE")
+          options[:on_update] = extract_foreign_key_action(row["on_update"])
+          options[:on_delete] = extract_foreign_key_action(row["on_delete"])
 
-          ForeignKeyDefinition.new(table_name, row['to_table'], options)
+          ForeignKeyDefinition.new(table_name, row["to_table"], options)
         end
       end
 
-      def table_options(table_name)
+      def table_options(table_name) # :nodoc:
+        table_options = {}
+
         create_table_info = create_table_info(table_name)
 
         # strip create_definitions and partition_options
-        raw_table_options = create_table_info.sub(/\A.*\n\) /m, '').sub(/\n\/\*!.*\*\/\n\z/m, '').strip
+        raw_table_options = create_table_info.sub(/\A.*\n\) /m, "").sub(/\n\/\*!.*\*\/\n\z/m, "").strip
 
         # strip AUTO_INCREMENT
         raw_table_options.sub!(/(ENGINE=\w+)(?: AUTO_INCREMENT=\d+)/, '\1')
 
+        table_options[:options] = raw_table_options
+
         # strip COMMENT
-        raw_table_options.sub!(/ COMMENT='.+'/, '')
+        if raw_table_options.sub!(/ COMMENT='.+'/, "")
+          table_options[:comment] = table_comment(table_name)
+        end
 
-        raw_table_options
+        table_options
       end
 
       # Maps logical Rails types to MySQL-specific data types.
-      def type_to_sql(type, limit = nil, precision = nil, scale = nil, unsigned = nil)
-        sql = case type.to_s
-        when 'integer'
-          integer_to_sql(limit)
-        when 'text'
-          text_to_sql(limit)
-        when 'blob'
-          binary_to_sql(limit)
-        when 'binary'
-          if (0..0xfff) === limit
-            "varbinary(#{limit})"
-          else
+      def type_to_sql(type, limit: nil, precision: nil, scale: nil, unsigned: nil, **) # :nodoc:
+        sql = \
+          case type.to_s
+          when "integer"
+            integer_to_sql(limit)
+          when "text"
+            text_to_sql(limit)
+          when "blob"
             binary_to_sql(limit)
+          when "binary"
+            if (0..0xfff) === limit
+              "varbinary(#{limit})"
+            else
+              binary_to_sql(limit)
+            end
+          else
+            super
           end
-        else
-          super(type, limit, precision, scale)
-        end
 
-        sql << ' unsigned' if unsigned && type != :primary_key
+        sql = "#{sql} unsigned" if unsigned && type != :primary_key
         sql
       end
 
       # SHOW VARIABLES LIKE 'name'
       def show_variable(name)
-        select_value("SELECT @@#{name}", 'SCHEMA')
+        query_value("SELECT @@#{name}", "SCHEMA")
       rescue ActiveRecord::StatementInvalid
         nil
       end
@@ -590,21 +478,21 @@ module ActiveRecord
       def primary_keys(table_name) # :nodoc:
         raise ArgumentError unless table_name.present?
 
-        schema, name = extract_schema_qualified_name(table_name)
+        scope = quoted_scope(table_name)
 
-        select_values(<<-SQL.strip_heredoc, 'SCHEMA')
+        query_values(<<-SQL.strip_heredoc, "SCHEMA")
           SELECT column_name
           FROM information_schema.key_column_usage
           WHERE constraint_name = 'PRIMARY'
-            AND table_schema = #{quote(schema)}
-            AND table_name = #{quote(name)}
+            AND table_schema = #{scope[:schema]}
+            AND table_name = #{scope[:name]}
           ORDER BY ordinal_position
         SQL
       end
 
-      def case_sensitive_comparison(table, attribute, column, value)
-        if !value.nil? && column.collation && !column.case_sensitive?
-          table[attribute].eq(Arel::Nodes::Bin.new(Arel::Nodes::BindParam.new))
+      def case_sensitive_comparison(table, attribute, column, value) # :nodoc:
+        if column.collation && !column.case_sensitive?
+          table[attribute].eq(Arel::Nodes::Bin.new(value))
         else
           super
         end
@@ -624,362 +512,351 @@ module ActiveRecord
           # Convert Arel node to string
           s = s.to_sql unless s.is_a?(String)
           # Remove any ASC/DESC modifiers
-          s.gsub(/\s+(?:ASC|DESC)\b/i, '')
+          s.gsub(/\s+(?:ASC|DESC)\b/i, "")
         }.reject(&:blank?).map.with_index { |column, i| "#{column} AS alias_#{i}" }
 
-        [super, *order_columns].join(', ')
+        [super, *order_columns].join(", ")
       end
 
       def strict_mode?
         self.class.type_cast_config_to_boolean(@config.fetch(:strict, true))
       end
 
-      def valid_type?(type)
-        !native_database_types[type].nil?
+      def default_index_type?(index) # :nodoc:
+        index.using == :btree || super
       end
 
-      protected
+      def insert_fixtures(*)
+        without_sql_mode("NO_AUTO_VALUE_ON_ZERO") { super }
+      end
 
-      def initialize_type_map(m) # :nodoc:
-        super
+      private
 
-        register_class_with_limit m, %r(char)i, MysqlString
+        def without_sql_mode(mode)
+          result = execute("SELECT @@SESSION.sql_mode")
+          current_mode = result.first[0]
+          return yield unless current_mode.include?(mode)
 
-        m.register_type %r(tinytext)i,   Type::Text.new(limit: 2**8 - 1)
-        m.register_type %r(tinyblob)i,   Type::Binary.new(limit: 2**8 - 1)
-        m.register_type %r(text)i,       Type::Text.new(limit: 2**16 - 1)
-        m.register_type %r(blob)i,       Type::Binary.new(limit: 2**16 - 1)
-        m.register_type %r(mediumtext)i, Type::Text.new(limit: 2**24 - 1)
-        m.register_type %r(mediumblob)i, Type::Binary.new(limit: 2**24 - 1)
-        m.register_type %r(longtext)i,   Type::Text.new(limit: 2**32 - 1)
-        m.register_type %r(longblob)i,   Type::Binary.new(limit: 2**32 - 1)
-        m.register_type %r(^float)i,     Type::Float.new(limit: 24)
-        m.register_type %r(^double)i,    Type::Float.new(limit: 53)
-        m.register_type %r(^json)i,      MysqlJson.new
+          sql_mode = "REPLACE(@@sql_mode, '#{mode}', '')"
+          execute("SET @@SESSION.sql_mode = #{sql_mode}")
+          yield
+        ensure
+          sql_mode = "CONCAT(@@sql_mode, ',#{mode}')"
+          execute("SET @@SESSION.sql_mode = #{sql_mode}")
+        end
 
-        register_integer_type m, %r(^bigint)i,    limit: 8
-        register_integer_type m, %r(^int)i,       limit: 4
-        register_integer_type m, %r(^mediumint)i, limit: 3
-        register_integer_type m, %r(^smallint)i,  limit: 2
-        register_integer_type m, %r(^tinyint)i,   limit: 1
+        def initialize_type_map(m = type_map)
+          super
 
-        m.register_type %r(^tinyint\(1\))i, Type::Boolean.new if emulate_booleans
-        m.alias_type %r(year)i,          'integer'
-        m.alias_type %r(bit)i,           'binary'
+          register_class_with_limit m, %r(char)i, MysqlString
+
+          m.register_type %r(tinytext)i,   Type::Text.new(limit: 2**8 - 1)
+          m.register_type %r(tinyblob)i,   Type::Binary.new(limit: 2**8 - 1)
+          m.register_type %r(text)i,       Type::Text.new(limit: 2**16 - 1)
+          m.register_type %r(blob)i,       Type::Binary.new(limit: 2**16 - 1)
+          m.register_type %r(mediumtext)i, Type::Text.new(limit: 2**24 - 1)
+          m.register_type %r(mediumblob)i, Type::Binary.new(limit: 2**24 - 1)
+          m.register_type %r(longtext)i,   Type::Text.new(limit: 2**32 - 1)
+          m.register_type %r(longblob)i,   Type::Binary.new(limit: 2**32 - 1)
+          m.register_type %r(^float)i,     Type::Float.new(limit: 24)
+          m.register_type %r(^double)i,    Type::Float.new(limit: 53)
+
+          register_integer_type m, %r(^bigint)i,    limit: 8
+          register_integer_type m, %r(^int)i,       limit: 4
+          register_integer_type m, %r(^mediumint)i, limit: 3
+          register_integer_type m, %r(^smallint)i,  limit: 2
+          register_integer_type m, %r(^tinyint)i,   limit: 1
+
+          m.register_type %r(^tinyint\(1\))i, Type::Boolean.new if emulate_booleans
+          m.alias_type %r(year)i,          "integer"
+          m.alias_type %r(bit)i,           "binary"
+
+          m.register_type(%r(enum)i) do |sql_type|
+            limit = sql_type[/^enum\((.+)\)/i, 1]
+              .split(",").map { |enum| enum.strip.length - 2 }.max
+            MysqlString.new(limit: limit)
+          end
 
-        m.register_type(%r(enum)i) do |sql_type|
-          limit = sql_type[/^enum\((.+)\)/i, 1]
-            .split(',').map{|enum| enum.strip.length - 2}.max
-          MysqlString.new(limit: limit)
+          m.register_type(%r(^set)i) do |sql_type|
+            limit = sql_type[/^set\((.+)\)/i, 1]
+              .split(",").map { |set| set.strip.length - 1 }.sum - 1
+            MysqlString.new(limit: limit)
+          end
         end
 
-        m.register_type(%r(^set)i) do |sql_type|
-          limit = sql_type[/^set\((.+)\)/i, 1]
-            .split(',').map{|set| set.strip.length - 1}.sum - 1
-          MysqlString.new(limit: limit)
+        def register_integer_type(mapping, key, options)
+          mapping.register_type(key) do |sql_type|
+            if /\bunsigned\b/.match?(sql_type)
+              Type::UnsignedInteger.new(options)
+            else
+              Type::Integer.new(options)
+            end
+          end
         end
-      end
 
-      def register_integer_type(mapping, key, options) # :nodoc:
-        mapping.register_type(key) do |sql_type|
-          if /\bunsigned\z/ === sql_type
-            Type::UnsignedInteger.new(options)
+        def extract_precision(sql_type)
+          if /\A(?:date)?time(?:stamp)?\b/.match?(sql_type)
+            super || 0
           else
-            Type::Integer.new(options)
+            super
           end
         end
-      end
-
-      def extract_precision(sql_type)
-        if /time/ === sql_type
-          super || 0
-        else
-          super
-        end
-      end
-
-      def fetch_type_metadata(sql_type, extra = "")
-        MySQL::TypeMetadata.new(super(sql_type), extra: extra, strict: strict_mode?)
-      end
 
-      def add_index_length(option_strings, column_names, options = {})
-        if options.is_a?(Hash) && length = options[:length]
-          case length
-          when Hash
-            column_names.each {|name| option_strings[name] += "(#{length[name]})" if length.has_key?(name) && length[name].present?}
-          when Integer
-            column_names.each {|name| option_strings[name] += "(#{length})"}
+        # See https://dev.mysql.com/doc/refman/5.7/en/error-messages-server.html
+        ER_DUP_ENTRY            = 1062
+        ER_NOT_NULL_VIOLATION   = 1048
+        ER_DO_NOT_HAVE_DEFAULT  = 1364
+        ER_NO_REFERENCED_ROW_2  = 1452
+        ER_DATA_TOO_LONG        = 1406
+        ER_OUT_OF_RANGE         = 1264
+        ER_LOCK_DEADLOCK        = 1213
+        ER_CANNOT_ADD_FOREIGN   = 1215
+        ER_CANNOT_CREATE_TABLE  = 1005
+        ER_LOCK_WAIT_TIMEOUT    = 1205
+        ER_QUERY_INTERRUPTED    = 1317
+        ER_QUERY_TIMEOUT        = 3024
+
+        def translate_exception(exception, message)
+          case error_number(exception)
+          when ER_DUP_ENTRY
+            RecordNotUnique.new(message)
+          when ER_NO_REFERENCED_ROW_2
+            InvalidForeignKey.new(message)
+          when ER_CANNOT_ADD_FOREIGN
+            mismatched_foreign_key(message)
+          when ER_CANNOT_CREATE_TABLE
+            if message.include?("errno: 150")
+              mismatched_foreign_key(message)
+            else
+              super
+            end
+          when ER_DATA_TOO_LONG
+            ValueTooLong.new(message)
+          when ER_OUT_OF_RANGE
+            RangeError.new(message)
+          when ER_NOT_NULL_VIOLATION, ER_DO_NOT_HAVE_DEFAULT
+            NotNullViolation.new(message)
+          when ER_LOCK_DEADLOCK
+            Deadlocked.new(message)
+          when ER_LOCK_WAIT_TIMEOUT
+            LockWaitTimeout.new(message)
+          when ER_QUERY_TIMEOUT
+            StatementTimeout.new(message)
+          when ER_QUERY_INTERRUPTED
+            QueryCanceled.new(message)
+          else
+            super
           end
         end
 
-        return option_strings
-      end
-
-      def quoted_columns_for_index(column_names, options = {})
-        option_strings = Hash[column_names.map {|name| [name, '']}]
-
-        # add index length
-        option_strings = add_index_length(option_strings, column_names, options)
+        def change_column_for_alter(table_name, column_name, type, options = {})
+          column = column_for(table_name, column_name)
+          type ||= column.sql_type
 
-        # add index sort order
-        option_strings = add_index_sort_order(option_strings, column_names, options)
+          unless options.key?(:default)
+            options[:default] = column.default
+          end
 
-        column_names.map {|name| quote_column_name(name) + option_strings[name]}
-      end
+          unless options.key?(:null)
+            options[:null] = column.null
+          end
 
-      # See https://dev.mysql.com/doc/refman/5.7/en/error-messages-server.html
-      ER_DUP_ENTRY            = 1062
-      ER_NO_REFERENCED_ROW_2  = 1452
-      ER_DATA_TOO_LONG        = 1406
-      ER_LOCK_DEADLOCK        = 1213
+          unless options.key?(:comment)
+            options[:comment] = column.comment
+          end
 
-      def translate_exception(exception, message)
-        case error_number(exception)
-        when ER_DUP_ENTRY
-          RecordNotUnique.new(message)
-        when ER_NO_REFERENCED_ROW_2
-          InvalidForeignKey.new(message)
-        when ER_DATA_TOO_LONG
-          ValueTooLong.new(message)
-        when ER_LOCK_DEADLOCK
-          TransactionSerializationError.new(message)
-        else
-          super
+          td = create_table_definition(table_name)
+          cd = td.new_column_definition(column.name, type, options)
+          schema_creation.accept(ChangeColumnDefinition.new(cd, column.name))
         end
-      end
-
-      def add_column_sql(table_name, column_name, type, options = {})
-        td = create_table_definition(table_name)
-        cd = td.new_column_definition(column_name, type, options)
-        schema_creation.accept(AddColumnDefinition.new(cd))
-      end
 
-      def change_column_sql(table_name, column_name, type, options = {})
-        column = column_for(table_name, column_name)
+        def rename_column_for_alter(table_name, column_name, new_column_name)
+          column  = column_for(table_name, column_name)
+          options = {
+            default: column.default,
+            null: column.null,
+            auto_increment: column.auto_increment?
+          }
 
-        unless options_include_default?(options)
-          options[:default] = column.default
+          current_type = exec_query("SHOW COLUMNS FROM #{quote_table_name(table_name)} LIKE #{quote(column_name)}", "SCHEMA").first["Type"]
+          td = create_table_definition(table_name)
+          cd = td.new_column_definition(new_column_name, current_type, options)
+          schema_creation.accept(ChangeColumnDefinition.new(cd, column.name))
         end
 
-        unless options.has_key?(:null)
-          options[:null] = column.null
+        def add_index_for_alter(table_name, column_name, options = {})
+          index_name, index_type, index_columns, _, index_algorithm, index_using = add_index_options(table_name, column_name, options)
+          index_algorithm[0, 0] = ", " if index_algorithm.present?
+          "ADD #{index_type} INDEX #{quote_column_name(index_name)} #{index_using} (#{index_columns})#{index_algorithm}"
         end
 
-        td = create_table_definition(table_name)
-        cd = td.new_column_definition(column.name, type, options)
-        schema_creation.accept(ChangeColumnDefinition.new(cd, column.name))
-      end
-
-      def rename_column_sql(table_name, column_name, new_column_name)
-        column  = column_for(table_name, column_name)
-        options = {
-          default: column.default,
-          null: column.null,
-          auto_increment: column.auto_increment?
-        }
-
-        current_type = select_one("SHOW COLUMNS FROM #{quote_table_name(table_name)} LIKE '#{column_name}'", 'SCHEMA')["Type"]
-        td = create_table_definition(table_name)
-        cd = td.new_column_definition(new_column_name, current_type, options)
-        schema_creation.accept(ChangeColumnDefinition.new(cd, column.name))
-      end
-
-      def remove_column_sql(table_name, column_name, type = nil, options = {})
-        "DROP #{quote_column_name(column_name)}"
-      end
-
-      def remove_columns_sql(table_name, *column_names)
-        column_names.map {|column_name| remove_column_sql(table_name, column_name) }
-      end
-
-      def add_index_sql(table_name, column_name, options = {})
-        index_name, index_type, index_columns, _, index_algorithm, index_using = add_index_options(table_name, column_name, options)
-        index_algorithm[0, 0] = ", " if index_algorithm.present?
-        "ADD #{index_type} INDEX #{quote_column_name(index_name)} #{index_using} (#{index_columns})#{index_algorithm}"
-      end
-
-      def remove_index_sql(table_name, options = {})
-        index_name = index_name_for_remove(table_name, options)
-        "DROP INDEX #{index_name}"
-      end
-
-      def add_timestamps_sql(table_name, options = {})
-        [add_column_sql(table_name, :created_at, :datetime, options), add_column_sql(table_name, :updated_at, :datetime, options)]
-      end
+        def remove_index_for_alter(table_name, options = {})
+          index_name = index_name_for_remove(table_name, options)
+          "DROP INDEX #{quote_column_name(index_name)}"
+        end
 
-      def remove_timestamps_sql(table_name, options = {})
-        [remove_column_sql(table_name, :updated_at), remove_column_sql(table_name, :created_at)]
-      end
+        def add_timestamps_for_alter(table_name, options = {})
+          [add_column_for_alter(table_name, :created_at, :datetime, options), add_column_for_alter(table_name, :updated_at, :datetime, options)]
+        end
 
-      private
+        def remove_timestamps_for_alter(table_name, options = {})
+          [remove_column_for_alter(table_name, :updated_at), remove_column_for_alter(table_name, :created_at)]
+        end
 
-      # MySQL is too stupid to create a temporary table for use subquery, so we have
-      # to give it some prompting in the form of a subsubquery. Ugh!
-      def subquery_for(key, select)
-        subsubselect = select.clone
-        subsubselect.projections = [key]
+        # MySQL is too stupid to create a temporary table for use subquery, so we have
+        # to give it some prompting in the form of a subsubquery. Ugh!
+        def subquery_for(key, select)
+          subselect = select.clone
+          subselect.projections = [key]
 
-        # Materialize subquery by adding distinct
-        # to work with MySQL 5.7.6 which sets optimizer_switch='derived_merge=on'
-        subsubselect.distinct unless select.limit || select.offset || select.orders.any?
+          # Materialize subquery by adding distinct
+          # to work with MySQL 5.7.6 which sets optimizer_switch='derived_merge=on'
+          subselect.distinct unless select.limit || select.offset || select.orders.any?
 
-        subselect = Arel::SelectManager.new(select.engine)
-        subselect.project Arel.sql(key.name)
-        subselect.from subsubselect.as('__active_record_temp')
-      end
+          key_name = quote_column_name(key.name)
+          Arel::SelectManager.new(subselect.as("__active_record_temp")).project(Arel.sql(key_name))
+        end
 
-      def supports_rename_index?
-        mariadb? ? false : version >= '5.7.6'
-      end
+        def supports_rename_index?
+          mariadb? ? false : version >= "5.7.6"
+        end
 
-      def configure_connection
-        variables = @config.fetch(:variables, {}).stringify_keys
+        def configure_connection
+          variables = @config.fetch(:variables, {}).stringify_keys
 
-        # By default, MySQL 'where id is null' selects the last inserted id; Turn this off.
-        variables['sql_auto_is_null'] = 0
+          # By default, MySQL 'where id is null' selects the last inserted id; Turn this off.
+          variables["sql_auto_is_null"] = 0
 
-        # Increase timeout so the server doesn't disconnect us.
-        wait_timeout = @config[:wait_timeout]
-        wait_timeout = 2147483 unless wait_timeout.is_a?(Integer)
-        variables['wait_timeout'] = self.class.type_cast_config_to_integer(wait_timeout)
+          # Increase timeout so the server doesn't disconnect us.
+          wait_timeout = self.class.type_cast_config_to_integer(@config[:wait_timeout])
+          wait_timeout = 2147483 unless wait_timeout.is_a?(Integer)
+          variables["wait_timeout"] = wait_timeout
 
-        defaults = [':default', :default].to_set
+          defaults = [":default", :default].to_set
 
-        # Make MySQL reject illegal values rather than truncating or blanking them, see
-        # http://dev.mysql.com/doc/refman/5.7/en/sql-mode.html#sqlmode_strict_all_tables
-        # If the user has provided another value for sql_mode, don't replace it.
-        if sql_mode = variables.delete('sql_mode')
-          sql_mode = quote(sql_mode)
-        elsif !defaults.include?(strict_mode?)
-          if strict_mode?
-            sql_mode = "CONCAT(@@sql_mode, ',STRICT_ALL_TABLES')"
-          else
-            sql_mode = "REPLACE(@@sql_mode, 'STRICT_TRANS_TABLES', '')"
-            sql_mode = "REPLACE(#{sql_mode}, 'STRICT_ALL_TABLES', '')"
-            sql_mode = "REPLACE(#{sql_mode}, 'TRADITIONAL', '')"
+          # Make MySQL reject illegal values rather than truncating or blanking them, see
+          # https://dev.mysql.com/doc/refman/5.7/en/sql-mode.html#sqlmode_strict_all_tables
+          # If the user has provided another value for sql_mode, don't replace it.
+          if sql_mode = variables.delete("sql_mode")
+            sql_mode = quote(sql_mode)
+          elsif !defaults.include?(strict_mode?)
+            if strict_mode?
+              sql_mode = "CONCAT(@@sql_mode, ',STRICT_ALL_TABLES')"
+            else
+              sql_mode = "REPLACE(@@sql_mode, 'STRICT_TRANS_TABLES', '')"
+              sql_mode = "REPLACE(#{sql_mode}, 'STRICT_ALL_TABLES', '')"
+              sql_mode = "REPLACE(#{sql_mode}, 'TRADITIONAL', '')"
+            end
+            sql_mode = "CONCAT(#{sql_mode}, ',NO_AUTO_VALUE_ON_ZERO')"
           end
-          sql_mode = "CONCAT(#{sql_mode}, ',NO_AUTO_VALUE_ON_ZERO')"
-        end
-        sql_mode_assignment = "@@SESSION.sql_mode = #{sql_mode}, " if sql_mode
-
-        # NAMES does not have an equals sign, see
-        # http://dev.mysql.com/doc/refman/5.7/en/set-statement.html#id944430
-        # (trailing comma because variable_assignments will always have content)
-        if @config[:encoding]
-          encoding = "NAMES #{@config[:encoding]}"
-          encoding << " COLLATE #{@config[:collation]}" if @config[:collation]
-          encoding << ", "
-        end
-
-        # Gather up all of the SET variables...
-        variable_assignments = variables.map do |k, v|
-          if defaults.include?(v)
-            "@@SESSION.#{k} = DEFAULT" # Sets the value to the global or compile default
-          elsif !v.nil?
-            "@@SESSION.#{k} = #{quote(v)}"
+          sql_mode_assignment = "@@SESSION.sql_mode = #{sql_mode}, " if sql_mode
+
+          # NAMES does not have an equals sign, see
+          # https://dev.mysql.com/doc/refman/5.7/en/set-names.html
+          # (trailing comma because variable_assignments will always have content)
+          if @config[:encoding]
+            encoding = "NAMES #{@config[:encoding]}".dup
+            encoding << " COLLATE #{@config[:collation]}" if @config[:collation]
+            encoding << ", "
           end
-          # or else nil; compact to clear nils out
-        end.compact.join(', ')
 
-        # ...and send them all in one query
-        @connection.query  "SET #{encoding} #{sql_mode_assignment} #{variable_assignments}"
-      end
+          # Gather up all of the SET variables...
+          variable_assignments = variables.map do |k, v|
+            if defaults.include?(v)
+              "@@SESSION.#{k} = DEFAULT" # Sets the value to the global or compile default
+            elsif !v.nil?
+              "@@SESSION.#{k} = #{quote(v)}"
+            end
+            # or else nil; compact to clear nils out
+          end.compact.join(", ")
 
-      def column_definitions(table_name) # :nodoc:
-        execute_and_free("SHOW FULL FIELDS FROM #{quote_table_name(table_name)}", 'SCHEMA') do |result|
-          each_hash(result)
+          # ...and send them all in one query
+          execute "SET #{encoding} #{sql_mode_assignment} #{variable_assignments}"
         end
-      end
 
-      def extract_foreign_key_action(structure, name, action) # :nodoc:
-        if structure =~ /CONSTRAINT #{quote_column_name(name)} FOREIGN KEY .* REFERENCES .* ON #{action} (CASCADE|SET NULL|RESTRICT)/
-          case $1
-          when 'CASCADE'; :cascade
-          when 'SET NULL'; :nullify
+        def column_definitions(table_name) # :nodoc:
+          execute_and_free("SHOW FULL FIELDS FROM #{quote_table_name(table_name)}", "SCHEMA") do |result|
+            each_hash(result)
           end
         end
-      end
-
-      def create_table_info_cache # :nodoc:
-        @create_table_info_cache ||= {}
-      end
 
-      def create_table_info(table_name) # :nodoc:
-        create_table_info_cache[table_name] ||= select_one("SHOW CREATE TABLE #{quote_table_name(table_name)}")["Create Table"]
-      end
-
-      def create_table_definition(*args) # :nodoc:
-        MySQL::TableDefinition.new(*args)
-      end
-
-      def extract_schema_qualified_name(string) # :nodoc:
-        schema, name = string.to_s.scan(/[^`.\s]+|`[^`]*`/)
-        schema, name = @config[:database], schema unless name
-        [schema, name]
-      end
+        def create_table_info(table_name) # :nodoc:
+          exec_query("SHOW CREATE TABLE #{quote_table_name(table_name)}", "SCHEMA").first["Create Table"]
+        end
 
-      def integer_to_sql(limit) # :nodoc:
-        case limit
-        when 1; 'tinyint'
-        when 2; 'smallint'
-        when 3; 'mediumint'
-        when nil, 4; 'int'
-        when 5..8; 'bigint'
-        else raise(ActiveRecordError, "No integer type has byte size #{limit}")
+        def arel_visitor
+          Arel::Visitors::MySQL.new(self)
         end
-      end
 
-      def text_to_sql(limit) # :nodoc:
-        case limit
-        when 0..0xff;               'tinytext'
-        when nil, 0x100..0xffff;    'text'
-        when 0x10000..0xffffff;     'mediumtext'
-        when 0x1000000..0xffffffff; 'longtext'
-        else raise(ActiveRecordError, "No text type has byte length #{limit}")
+        def mismatched_foreign_key(message)
+          parts = message.scan(/`(\w+)`[ $)]/).flatten
+          MismatchedForeignKey.new(
+            self,
+            message: message,
+            table: parts[0],
+            foreign_key: parts[1],
+            target_table: parts[2],
+            primary_key: parts[3],
+          )
         end
-      end
 
-      def binary_to_sql(limit) # :nodoc:
-        case limit
-        when 0..0xff;               'tinyblob'
-        when nil, 0x100..0xffff;    'blob'
-        when 0x10000..0xffffff;     'mediumblob'
-        when 0x1000000..0xffffffff; 'longblob'
-        else raise(ActiveRecordError, "No binary type has byte length #{limit}")
+        def integer_to_sql(limit) # :nodoc:
+          case limit
+          when 1; "tinyint"
+          when 2; "smallint"
+          when 3; "mediumint"
+          when nil, 4; "int"
+          when 5..8; "bigint"
+          else raise(ActiveRecordError, "No integer type has byte size #{limit}. Use a decimal with scale 0 instead.")
+          end
         end
-      end
 
-      class MysqlJson < Type::Internal::AbstractJson # :nodoc:
-        def changed_in_place?(raw_old_value, new_value)
-          # Normalization is required because MySQL JSON data format includes
-          # the space between the elements.
-          super(serialize(deserialize(raw_old_value)), new_value)
+        def text_to_sql(limit) # :nodoc:
+          case limit
+          when 0..0xff;               "tinytext"
+          when nil, 0x100..0xffff;    "text"
+          when 0x10000..0xffffff;     "mediumtext"
+          when 0x1000000..0xffffffff; "longtext"
+          else raise(ActiveRecordError, "No text type has byte length #{limit}")
+          end
         end
-      end
 
-      class MysqlString < Type::String # :nodoc:
-        def serialize(value)
-          case value
-          when true then MySQL::Quoting::QUOTED_TRUE
-          when false then MySQL::Quoting::QUOTED_FALSE
-          else super
+        def binary_to_sql(limit) # :nodoc:
+          case limit
+          when 0..0xff;               "tinyblob"
+          when nil, 0x100..0xffff;    "blob"
+          when 0x10000..0xffffff;     "mediumblob"
+          when 0x1000000..0xffffffff; "longblob"
+          else raise(ActiveRecordError, "No binary type has byte length #{limit}")
           end
         end
 
-        private
+        def version_string
+          full_version.match(/^(?:5\.5\.5-)?(\d+\.\d+\.\d+)/)[1]
+        end
 
-        def cast_value(value)
-          case value
-          when true then MySQL::Quoting::QUOTED_TRUE
-          when false then MySQL::Quoting::QUOTED_FALSE
-          else super
+        class MysqlString < Type::String # :nodoc:
+          def serialize(value)
+            case value
+            when true then "1"
+            when false then "0"
+            else super
+            end
           end
+
+          private
+
+            def cast_value(value)
+              case value
+              when true then "1"
+              when false then "0"
+              else super
+              end
+            end
         end
-      end
 
-      ActiveRecord::Type.register(:json, MysqlJson, adapter: :mysql2)
-      ActiveRecord::Type.register(:string, MysqlString, adapter: :mysql2)
-      ActiveRecord::Type.register(:unsigned_integer, Type::UnsignedInteger, adapter: :mysql2)
+        ActiveRecord::Type.register(:string, MysqlString, adapter: :mysql2)
+        ActiveRecord::Type.register(:unsigned_integer, Type::UnsignedInteger, adapter: :mysql2)
     end
   end
 end
diff --git a/activerecord/lib/active_record/connection_adapters/column.rb b/activerecord/lib/active_record/connection_adapters/column.rb
index 28f0c8686a..5d81de9fe1 100644
--- a/activerecord/lib/active_record/connection_adapters/column.rb
+++ b/activerecord/lib/active_record/connection_adapters/column.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActiveRecord
   # :stopdoc:
   module ConnectionAdapters
@@ -9,11 +11,11 @@ module ActiveRecord
 
       # Instantiates a new column in the table.
       #
-      # +name+ is the column's name, such as <tt>supplier_id</tt> in <tt>supplier_id int</tt>.
+      # +name+ is the column's name, such as <tt>supplier_id</tt> in <tt>supplier_id bigint</tt>.
       # +default+ is the type-casted default value, such as +new+ in <tt>sales_stage varchar(20) default 'new'</tt>.
       # +sql_type_metadata+ is various information about the type of the column
       # +null+ determines if this column allows +NULL+ values.
-      def initialize(name, default, sql_type_metadata = nil, null = true, table_name = nil, default_function = nil, collation = nil, comment: nil)
+      def initialize(name, default, sql_type_metadata = nil, null = true, table_name = nil, default_function = nil, collation = nil, comment: nil, **)
         @name = name.freeze
         @table_name = table_name
         @sql_type_metadata = sql_type_metadata
@@ -29,7 +31,7 @@ module ActiveRecord
       end
 
       def bigint?
-        /\Abigint\b/ === sql_type
+        /\Abigint\b/.match?(sql_type)
       end
 
       # Returns the human name of the column name.
@@ -40,6 +42,28 @@ module ActiveRecord
         Base.human_attribute_name(@name)
       end
 
+      def init_with(coder)
+        @name = coder["name"]
+        @table_name = coder["table_name"]
+        @sql_type_metadata = coder["sql_type_metadata"]
+        @null = coder["null"]
+        @default = coder["default"]
+        @default_function = coder["default_function"]
+        @collation = coder["collation"]
+        @comment = coder["comment"]
+      end
+
+      def encode_with(coder)
+        coder["name"] = @name
+        coder["table_name"] = @table_name
+        coder["sql_type_metadata"] = @sql_type_metadata
+        coder["null"] = @null
+        coder["default"] = @default
+        coder["default_function"] = @default_function
+        coder["collation"] = @collation
+        coder["comment"] = @comment
+      end
+
       def ==(other)
         other.is_a?(Column) &&
           attributes_for_hash == other.attributes_for_hash
@@ -52,9 +76,9 @@ module ActiveRecord
 
       protected
 
-      def attributes_for_hash
-        [self.class, name, default, sql_type_metadata, null, table_name, default_function, collation]
-      end
+        def attributes_for_hash
+          [self.class, name, default, sql_type_metadata, null, table_name, default_function, collation]
+        end
     end
 
     class NullColumn < Column
diff --git a/activerecord/lib/active_record/connection_adapters/connection_specification.rb b/activerecord/lib/active_record/connection_adapters/connection_specification.rb
index 346916337e..508132accb 100644
--- a/activerecord/lib/active_record/connection_adapters/connection_specification.rb
+++ b/activerecord/lib/active_record/connection_adapters/connection_specification.rb
@@ -1,4 +1,6 @@
-require 'uri'
+# frozen_string_literal: true
+
+require "uri"
 
 module ActiveRecord
   module ConnectionAdapters
@@ -19,7 +21,6 @@ module ActiveRecord
 
       # Expands a connection string into a hash.
       class ConnectionUrlResolver # :nodoc:
-
         # == Example
         #
         #   url = "postgresql://foo:bar@localhost:9000/foo_test?pool=5&timeout=3000"
@@ -37,11 +38,11 @@ module ActiveRecord
         def initialize(url)
           raise "Database URL cannot be empty" if url.blank?
           @uri     = uri_parser.parse(url)
-          @adapter = @uri.scheme && @uri.scheme.tr('-', '_')
+          @adapter = @uri.scheme && @uri.scheme.tr("-", "_")
           @adapter = "postgresql" if @adapter == "postgres"
 
           if @uri.opaque
-            @uri.opaque, @query = @uri.opaque.split('?', 2)
+            @uri.opaque, @query = @uri.opaque.split("?", 2)
           else
             @query = @uri.query
           end
@@ -49,65 +50,65 @@ module ActiveRecord
 
         # Converts the given URL to a full connection hash.
         def to_hash
-          config = raw_config.reject { |_,value| value.blank? }
-          config.map { |key,value| config[key] = uri_parser.unescape(value) if value.is_a? String }
+          config = raw_config.reject { |_, value| value.blank? }
+          config.map { |key, value| config[key] = uri_parser.unescape(value) if value.is_a? String }
           config
         end
 
         private
 
-        def uri
-          @uri
-        end
+          def uri
+            @uri
+          end
 
-        def uri_parser
-          @uri_parser ||= URI::Parser.new
-        end
+          def uri_parser
+            @uri_parser ||= URI::Parser.new
+          end
 
-        # Converts the query parameters of the URI into a hash.
-        #
-        #   "localhost?pool=5&reaping_frequency=2"
-        #   # => { "pool" => "5", "reaping_frequency" => "2" }
-        #
-        # returns empty hash if no query present.
-        #
-        #   "localhost"
-        #   # => {}
-        def query_hash
-          Hash[(@query || '').split("&").map { |pair| pair.split("=") }]
-        end
+          # Converts the query parameters of the URI into a hash.
+          #
+          #   "localhost?pool=5&reaping_frequency=2"
+          #   # => { "pool" => "5", "reaping_frequency" => "2" }
+          #
+          # returns empty hash if no query present.
+          #
+          #   "localhost"
+          #   # => {}
+          def query_hash
+            Hash[(@query || "").split("&").map { |pair| pair.split("=") }]
+          end
 
-        def raw_config
-          if uri.opaque
-            query_hash.merge({
-              "adapter"  => @adapter,
-              "database" => uri.opaque })
-          else
-            query_hash.merge({
-              "adapter"  => @adapter,
-              "username" => uri.user,
-              "password" => uri.password,
-              "port"     => uri.port,
-              "database" => database_from_path,
-              "host"     => uri.hostname })
+          def raw_config
+            if uri.opaque
+              query_hash.merge(
+                "adapter"  => @adapter,
+                "database" => uri.opaque)
+            else
+              query_hash.merge(
+                "adapter"  => @adapter,
+                "username" => uri.user,
+                "password" => uri.password,
+                "port"     => uri.port,
+                "database" => database_from_path,
+                "host"     => uri.hostname)
+            end
           end
-        end
 
-        # Returns name of the database.
-        def database_from_path
-          if @adapter == 'sqlite3'
-            # 'sqlite3:/foo' is absolute, because that makes sense. The
-            # corresponding relative version, 'sqlite3:foo', is handled
-            # elsewhere, as an "opaque".
+          # Returns name of the database.
+          def database_from_path
+            if @adapter == "sqlite3"
+              # 'sqlite3:/foo' is absolute, because that makes sense. The
+              # corresponding relative version, 'sqlite3:foo', is handled
+              # elsewhere, as an "opaque".
 
-            uri.path
-          else
-            # Only SQLite uses a filename as the "database" name; for
-            # anything else, a leading slash would be silly.
+              uri.path
+            else
+              # Only SQLite uses a filename as the "database" name; for
+              # anything else, a leading slash would be silly.
 
-            uri.path.sub(%r{^/}, "")
+              uri.path.sub(%r{^/}, "")
+            end
           end
-        end
       end
 
       ##
@@ -150,9 +151,18 @@ module ActiveRecord
         # Expands each key in @configurations hash into fully resolved hash
         def resolve_all
           config = configurations.dup
+
+          if env = ActiveRecord::ConnectionHandling::DEFAULT_ENV.call
+            env_config = config[env] if config[env].is_a?(Hash) && !(config[env].key?("adapter") || config[env].key?("url"))
+          end
+
+          config.reject! { |k, v| v.is_a?(Hash) && !(v.key?("adapter") || v.key?("url")) }
+          config.merge! env_config if env_config
+
           config.each do |key, value|
             config[key] = resolve(value) if value
           end
+
           config
         end
 
@@ -173,13 +183,25 @@ module ActiveRecord
 
           raise(AdapterNotSpecified, "database configuration does not specify adapter") unless spec.key?(:adapter)
 
+          # Require the adapter itself and give useful feedback about
+          #   1. Missing adapter gems and
+          #   2. Adapter gems' missing dependencies.
           path_to_adapter = "active_record/connection_adapters/#{spec[:adapter]}_adapter"
           begin
             require path_to_adapter
-          rescue Gem::LoadError => e
-            raise Gem::LoadError, "Specified '#{spec[:adapter]}' for database adapter, but the gem is not loaded. Add `gem '#{e.name}'` to your Gemfile (and ensure its version is at the minimum required by ActiveRecord)."
           rescue LoadError => e
-            raise LoadError, "Could not load '#{path_to_adapter}'. Make sure that the adapter in config/database.yml is valid. If you use an adapter other than 'mysql2', 'postgresql' or 'sqlite3' add the necessary adapter gem to the Gemfile.", e.backtrace
+            # We couldn't require the adapter itself. Raise an exception that
+            # points out config typos and missing gems.
+            if e.path == path_to_adapter
+              # We can assume that a non-builtin adapter was specified, so it's
+              # either misspelled or missing from Gemfile.
+              raise e.class, "Could not load the '#{spec[:adapter]}' Active Record adapter. Ensure that the adapter is spelled correctly in config/database.yml and that you've added the necessary adapter gem to your Gemfile.", e.backtrace
+
+            # Bubbled up from the adapter require. Prefix the exception message
+            # with some guidance about how to address it and reraise.
+            else
+              raise e.class, "Error loading the '#{spec[:adapter]}' Active Record adapter. Missing a gem it depends on? #{e.message}", e.backtrace
+            end
           end
 
           adapter_method = "#{spec[:adapter]}_connection"
@@ -193,72 +215,72 @@ module ActiveRecord
 
         private
 
-        # Returns fully resolved connection, accepts hash, string or symbol.
-        # Always returns a hash.
-        #
-        # == Examples
-        #
-        # Symbol representing current environment.
-        #
-        #   Resolver.new("production" => {}).resolve_connection(:production)
-        #   # => {}
-        #
-        # One layer deep hash of connection values.
-        #
-        #   Resolver.new({}).resolve_connection("adapter" => "sqlite3")
-        #   # => { "adapter" => "sqlite3" }
-        #
-        # Connection URL.
-        #
-        #   Resolver.new({}).resolve_connection("postgresql://localhost/foo")
-        #   # => { "host" => "localhost", "database" => "foo", "adapter" => "postgresql" }
-        #
-        def resolve_connection(spec)
-          case spec
-          when Symbol
-            resolve_symbol_connection spec
-          when String
-            resolve_url_connection spec
-          when Hash
-            resolve_hash_connection spec
+          # Returns fully resolved connection, accepts hash, string or symbol.
+          # Always returns a hash.
+          #
+          # == Examples
+          #
+          # Symbol representing current environment.
+          #
+          #   Resolver.new("production" => {}).resolve_connection(:production)
+          #   # => {}
+          #
+          # One layer deep hash of connection values.
+          #
+          #   Resolver.new({}).resolve_connection("adapter" => "sqlite3")
+          #   # => { "adapter" => "sqlite3" }
+          #
+          # Connection URL.
+          #
+          #   Resolver.new({}).resolve_connection("postgresql://localhost/foo")
+          #   # => { "host" => "localhost", "database" => "foo", "adapter" => "postgresql" }
+          #
+          def resolve_connection(spec)
+            case spec
+            when Symbol
+              resolve_symbol_connection spec
+            when String
+              resolve_url_connection spec
+            when Hash
+              resolve_hash_connection spec
+            end
           end
-        end
 
-        # Takes the environment such as +:production+ or +:development+.
-        # This requires that the @configurations was initialized with a key that
-        # matches.
-        #
-        #   Resolver.new("production" => {}).resolve_symbol_connection(:production)
-        #   # => {}
-        #
-        def resolve_symbol_connection(spec)
-          if config = configurations[spec.to_s]
-            resolve_connection(config).merge("name" => spec.to_s)
-          else
-            raise(AdapterNotSpecified, "'#{spec}' database is not configured. Available: #{configurations.keys.inspect}")
+          # Takes the environment such as +:production+ or +:development+.
+          # This requires that the @configurations was initialized with a key that
+          # matches.
+          #
+          #   Resolver.new("production" => {}).resolve_symbol_connection(:production)
+          #   # => {}
+          #
+          def resolve_symbol_connection(spec)
+            if config = configurations[spec.to_s]
+              resolve_connection(config).merge("name" => spec.to_s)
+            else
+              raise(AdapterNotSpecified, "'#{spec}' database is not configured. Available: #{configurations.keys.inspect}")
+            end
           end
-        end
 
-        # Accepts a hash. Expands the "url" key that contains a
-        # URL database connection to a full connection
-        # hash and merges with the rest of the hash.
-        # Connection details inside of the "url" key win any merge conflicts
-        def resolve_hash_connection(spec)
-          if spec["url"] && spec["url"] !~ /^jdbc:/
-            connection_hash = resolve_url_connection(spec.delete("url"))
-            spec.merge!(connection_hash)
+          # Accepts a hash. Expands the "url" key that contains a
+          # URL database connection to a full connection
+          # hash and merges with the rest of the hash.
+          # Connection details inside of the "url" key win any merge conflicts
+          def resolve_hash_connection(spec)
+            if spec["url"] && spec["url"] !~ /^jdbc:/
+              connection_hash = resolve_url_connection(spec.delete("url"))
+              spec.merge!(connection_hash)
+            end
+            spec
           end
-          spec
-        end
 
-        # Takes a connection URL.
-        #
-        #   Resolver.new({}).resolve_url_connection("postgresql://localhost/foo")
-        #   # => { "host" => "localhost", "database" => "foo", "adapter" => "postgresql" }
-        #
-        def resolve_url_connection(url)
-          ConnectionUrlResolver.new(url).to_hash
-        end
+          # Takes a connection URL.
+          #
+          #   Resolver.new({}).resolve_url_connection("postgresql://localhost/foo")
+          #   # => { "host" => "localhost", "database" => "foo", "adapter" => "postgresql" }
+          #
+          def resolve_url_connection(url)
+            ConnectionUrlResolver.new(url).to_hash
+          end
       end
     end
   end
diff --git a/activerecord/lib/active_record/connection_adapters/determine_if_preparable_visitor.rb b/activerecord/lib/active_record/connection_adapters/determine_if_preparable_visitor.rb
index 0fdc185c45..3dcb916d99 100644
--- a/activerecord/lib/active_record/connection_adapters/determine_if_preparable_visitor.rb
+++ b/activerecord/lib/active_record/connection_adapters/determine_if_preparable_visitor.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActiveRecord
   module ConnectionAdapters
     module DetermineIfPreparableVisitor
diff --git a/activerecord/lib/active_record/connection_adapters/mysql/column.rb b/activerecord/lib/active_record/connection_adapters/mysql/column.rb
index 9c45fdd44a..fa1541019d 100644
--- a/activerecord/lib/active_record/connection_adapters/mysql/column.rb
+++ b/activerecord/lib/active_record/connection_adapters/mysql/column.rb
@@ -1,48 +1,25 @@
+# frozen_string_literal: true
+
 module ActiveRecord
   module ConnectionAdapters
     module MySQL
       class Column < ConnectionAdapters::Column # :nodoc:
-        delegate :strict, :extra, to: :sql_type_metadata, allow_nil: true
-
-        def initialize(*)
-          super
-          assert_valid_default
-          extract_default
-        end
-
-        def has_default?
-          return false if blob_or_text_column? # MySQL forbids defaults on blob and text columns
-          super
-        end
-
-        def blob_or_text_column?
-          /\A(?:tiny|medium|long)?blob\b/ === sql_type || type == :text
-        end
+        delegate :extra, to: :sql_type_metadata, allow_nil: true
 
         def unsigned?
-          /\bunsigned\z/ === sql_type
+          /\bunsigned(?: zerofill)?\z/.match?(sql_type)
         end
 
         def case_sensitive?
-          collation && collation !~ /_ci\z/
+          collation && !/_ci\z/.match?(collation)
         end
 
         def auto_increment?
-          extra == 'auto_increment'
-        end
-
-        private
-
-        def extract_default
-          if blob_or_text_column?
-            @default = null || strict ? nil : ''
-          end
+          extra == "auto_increment"
         end
 
-        def assert_valid_default
-          if blob_or_text_column? && default.present?
-            raise ArgumentError, "#{type} columns cannot have a default value: #{default.inspect}"
-          end
+        def virtual?
+          /\b(?:VIRTUAL|STORED|PERSISTENT)\b/.match?(extra)
         end
       end
     end
diff --git a/activerecord/lib/active_record/connection_adapters/mysql/database_statements.rb b/activerecord/lib/active_record/connection_adapters/mysql/database_statements.rb
index 13c9b6cbd9..a058a72872 100644
--- a/activerecord/lib/active_record/connection_adapters/mysql/database_statements.rb
+++ b/activerecord/lib/active_record/connection_adapters/mysql/database_statements.rb
@@ -1,9 +1,11 @@
+# frozen_string_literal: true
+
 module ActiveRecord
   module ConnectionAdapters
     module MySQL
       module DatabaseStatements
         # Returns an ActiveRecord::Result instance.
-        def select_all(arel, name = nil, binds = [], preparable: nil)
+        def select_all(*) # :nodoc:
           result = if ExplainRegistry.collect? && prepared_statements
             unprepared_statement { super }
           else
@@ -13,40 +15,20 @@ module ActiveRecord
           result
         end
 
-        # Returns a record hash with the column names as keys and column values
-        # as values.
-        def select_one(arel, name = nil, binds = [])
-          arel, binds = binds_from_relation(arel, binds)
-          @connection.query_options.merge!(as: :hash)
-          select_result(to_sql(arel, binds), name, binds) do |result|
-            @connection.next_result while @connection.more_results?
-            result.first
-          end
-        ensure
-          @connection.query_options.merge!(as: :array)
-        end
-
-        # Returns an array of arrays containing the field values.
-        # Order is the same as that returned by +columns+.
-        def select_rows(sql, name = nil, binds = [])
-          select_result(sql, name, binds) do |result|
-            @connection.next_result while @connection.more_results?
-            result.to_a
-          end
+        def query(sql, name = nil) # :nodoc:
+          execute(sql, name).to_a
         end
 
         # Executes the SQL statement in the context of this connection.
         def execute(sql, name = nil)
-          if @connection
-            # make sure we carry over any changes to ActiveRecord::Base.default_timezone that have been
-            # made since we established the connection
-            @connection.query_options[:database_timezone] = ActiveRecord::Base.default_timezone
-          end
+          # make sure we carry over any changes to ActiveRecord::Base.default_timezone that have been
+          # made since we established the connection
+          @connection.query_options[:database_timezone] = ActiveRecord::Base.default_timezone
 
           super
         end
 
-        def exec_query(sql, name = 'SQL', binds = [], prepare: false)
+        def exec_query(sql, name = "SQL", binds = [], prepare: false)
           if without_prepared_statement?(binds)
             execute_and_free(sql, name) do |result|
               ActiveRecord::Result.new(result.fields, result.to_a) if result
@@ -58,7 +40,7 @@ module ActiveRecord
           end
         end
 
-        def exec_delete(sql, name, binds)
+        def exec_delete(sql, name = nil, binds = [])
           if without_prepared_statement?(binds)
             execute_and_free(sql, name) { @connection.affected_rows }
           else
@@ -67,58 +49,48 @@ module ActiveRecord
         end
         alias :exec_update :exec_delete
 
-        protected
-
-        def last_inserted_id(result)
-          @connection.last_id
-        end
-
         private
 
-        def select_result(sql, name = nil, binds = [])
-          if without_prepared_statement?(binds)
-            execute_and_free(sql, name) { |result| yield result }
-          else
-            exec_stmt_and_free(sql, name, binds, cache_stmt: true) { |_, result| yield result }
+          def last_inserted_id(result)
+            @connection.last_id
           end
-        end
 
-        def exec_stmt_and_free(sql, name, binds, cache_stmt: false)
-          if @connection
+          def exec_stmt_and_free(sql, name, binds, cache_stmt: false)
             # make sure we carry over any changes to ActiveRecord::Base.default_timezone that have been
             # made since we established the connection
             @connection.query_options[:database_timezone] = ActiveRecord::Base.default_timezone
-          end
-
-          type_casted_binds = binds.map { |attr| type_cast(attr.value_for_database) }
 
-          log(sql, name, binds) do
-            if cache_stmt
-              cache = @statements[sql] ||= {
-                stmt: @connection.prepare(sql)
-              }
-              stmt = cache[:stmt]
-            else
-              stmt = @connection.prepare(sql)
-            end
+            type_casted_binds = type_casted_binds(binds)
 
-            begin
-              result = stmt.execute(*type_casted_binds)
-            rescue Mysql2::Error => e
+            log(sql, name, binds, type_casted_binds) do
               if cache_stmt
-                @statements.delete(sql)
+                cache = @statements[sql] ||= {
+                  stmt: @connection.prepare(sql)
+                }
+                stmt = cache[:stmt]
               else
-                stmt.close
+                stmt = @connection.prepare(sql)
+              end
+
+              begin
+                result = ActiveSupport::Dependencies.interlock.permit_concurrent_loads do
+                  stmt.execute(*type_casted_binds)
+                end
+              rescue Mysql2::Error => e
+                if cache_stmt
+                  @statements.delete(sql)
+                else
+                  stmt.close
+                end
+                raise e
               end
-              raise e
-            end
 
-            ret = yield stmt, result
-            result.free if result
-            stmt.close unless cache_stmt
-            ret
+              ret = yield stmt, result
+              result.free if result
+              stmt.close unless cache_stmt
+              ret
+            end
           end
-        end
       end
     end
   end
diff --git a/activerecord/lib/active_record/connection_adapters/mysql/explain_pretty_printer.rb b/activerecord/lib/active_record/connection_adapters/mysql/explain_pretty_printer.rb
index 1820853196..20c3c83664 100644
--- a/activerecord/lib/active_record/connection_adapters/mysql/explain_pretty_printer.rb
+++ b/activerecord/lib/active_record/connection_adapters/mysql/explain_pretty_printer.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActiveRecord
   module ConnectionAdapters
     module MySQL
@@ -36,34 +38,34 @@ module ActiveRecord
 
         private
 
-        def compute_column_widths(result)
-          [].tap do |widths|
-            result.columns.each_with_index do |column, i|
-              cells_in_column = [column] + result.rows.map {|r| r[i].nil? ? 'NULL' : r[i].to_s}
-              widths << cells_in_column.map(&:length).max
+          def compute_column_widths(result)
+            [].tap do |widths|
+              result.columns.each_with_index do |column, i|
+                cells_in_column = [column] + result.rows.map { |r| r[i].nil? ? "NULL" : r[i].to_s }
+                widths << cells_in_column.map(&:length).max
+              end
             end
           end
-        end
 
-        def build_separator(widths)
-          padding = 1
-          '+' + widths.map {|w| '-' * (w + (padding*2))}.join('+') + '+'
-        end
+          def build_separator(widths)
+            padding = 1
+            "+" + widths.map { |w| "-" * (w + (padding * 2)) }.join("+") + "+"
+          end
 
-        def build_cells(items, widths)
-          cells = []
-          items.each_with_index do |item, i|
-            item = 'NULL' if item.nil?
-            justifier = item.is_a?(Numeric) ? 'rjust' : 'ljust'
-            cells << item.to_s.send(justifier, widths[i])
+          def build_cells(items, widths)
+            cells = []
+            items.each_with_index do |item, i|
+              item = "NULL" if item.nil?
+              justifier = item.is_a?(Numeric) ? "rjust" : "ljust"
+              cells << item.to_s.send(justifier, widths[i])
+            end
+            "| " + cells.join(" | ") + " |"
           end
-          '| ' + cells.join(' | ') + ' |'
-        end
 
-        def build_footer(nrows, elapsed)
-          rows_label = nrows == 1 ? 'row' : 'rows'
-          "#{nrows} #{rows_label} in set (%.2f sec)" % elapsed
-        end
+          def build_footer(nrows, elapsed)
+            rows_label = nrows == 1 ? "row" : "rows"
+            "#{nrows} #{rows_label} in set (%.2f sec)" % elapsed
+          end
       end
     end
   end
diff --git a/activerecord/lib/active_record/connection_adapters/mysql/quoting.rb b/activerecord/lib/active_record/connection_adapters/mysql/quoting.rb
index fbab654112..be038403b8 100644
--- a/activerecord/lib/active_record/connection_adapters/mysql/quoting.rb
+++ b/activerecord/lib/active_record/connection_adapters/mysql/quoting.rb
@@ -1,29 +1,21 @@
+# frozen_string_literal: true
+
 module ActiveRecord
   module ConnectionAdapters
     module MySQL
       module Quoting # :nodoc:
-        QUOTED_TRUE, QUOTED_FALSE = '1', '0'
-
         def quote_column_name(name)
-          @quoted_column_names[name] ||= "`#{super.gsub('`', '``')}`"
+          @quoted_column_names[name] ||= "`#{super.gsub('`', '``')}`".freeze
         end
 
         def quote_table_name(name)
-          @quoted_table_names[name] ||= super.gsub('.', '`.`')
-        end
-
-        def quoted_true
-          QUOTED_TRUE
+          @quoted_table_names[name] ||= super.gsub(".", "`.`").freeze
         end
 
         def unquoted_true
           1
         end
 
-        def quoted_false
-          QUOTED_FALSE
-        end
-
         def unquoted_false
           0
         end
@@ -32,17 +24,18 @@ module ActiveRecord
           if supports_datetime_with_precision?
             super
           else
-            super.sub(/\.\d{6}\z/, '')
+            super.sub(/\.\d{6}\z/, "")
           end
         end
 
-        private
+        def quoted_binary(value)
+          "x'#{value.hex}'"
+        end
 
-        def _quote(value)
-          if value.is_a?(Type::Binary::Data)
-            "x'#{value.hex}'"
-          else
-            super
+        def _type_cast(value)
+          case value
+          when Date, Time then value
+          else super
           end
         end
       end
diff --git a/activerecord/lib/active_record/connection_adapters/mysql/schema_creation.rb b/activerecord/lib/active_record/connection_adapters/mysql/schema_creation.rb
index fd2dc2aee8..75377693c6 100644
--- a/activerecord/lib/active_record/connection_adapters/mysql/schema_creation.rb
+++ b/activerecord/lib/active_record/connection_adapters/mysql/schema_creation.rb
@@ -1,66 +1,72 @@
+# frozen_string_literal: true
+
 module ActiveRecord
   module ConnectionAdapters
     module MySQL
-      class SchemaCreation < AbstractAdapter::SchemaCreation
-        delegate :add_sql_comment!, to: :@conn
-        private :add_sql_comment!
+      class SchemaCreation < AbstractAdapter::SchemaCreation # :nodoc:
+        delegate :add_sql_comment!, :mariadb?, to: :@conn
+        private :add_sql_comment!, :mariadb?
 
         private
 
-        def visit_DropForeignKey(name)
-          "DROP FOREIGN KEY #{name}"
-        end
+          def visit_DropForeignKey(name)
+            "DROP FOREIGN KEY #{name}"
+          end
 
-        def visit_ColumnDefinition(o)
-          o.sql_type = type_to_sql(o.type, o.limit, o.precision, o.scale, o.unsigned)
-          super
-        end
+          def visit_AddColumnDefinition(o)
+            add_column_position!(super, column_options(o.column))
+          end
 
-        def visit_AddColumnDefinition(o)
-          add_column_position!(super, column_options(o.column))
-        end
+          def visit_ChangeColumnDefinition(o)
+            change_column_sql = "CHANGE #{quote_column_name(o.name)} #{accept(o.column)}".dup
+            add_column_position!(change_column_sql, column_options(o.column))
+          end
 
-        def visit_ChangeColumnDefinition(o)
-          change_column_sql = "CHANGE #{quote_column_name(o.name)} #{accept(o.column)}"
-          add_column_position!(change_column_sql, column_options(o.column))
-        end
+          def add_table_options!(create_sql, options)
+            add_sql_comment!(super, options[:comment])
+          end
 
-        def add_table_options!(create_sql, options)
-          add_sql_comment!(super, options[:comment])
-        end
+          def add_column_options!(sql, options)
+            # By default, TIMESTAMP columns are NOT NULL, cannot contain NULL values,
+            # and assigning NULL assigns the current timestamp. To permit a TIMESTAMP
+            # column to contain NULL, explicitly declare it with the NULL attribute.
+            # See https://dev.mysql.com/doc/refman/5.7/en/timestamp-initialization.html
+            if /\Atimestamp\b/.match?(options[:column].sql_type) && !options[:primary_key]
+              sql << " NULL" unless options[:null] == false || options_include_default?(options)
+            end
 
-        def column_options(o)
-          column_options = super
-          column_options[:charset] = o.charset
-          column_options
-        end
+            if charset = options[:charset]
+              sql << " CHARACTER SET #{charset}"
+            end
 
-        def add_column_options!(sql, options)
-          if charset = options[:charset]
-            sql << " CHARACTER SET #{charset}"
-          end
+            if collation = options[:collation]
+              sql << " COLLATE #{collation}"
+            end
+
+            if as = options[:as]
+              sql << " AS (#{as})"
+              if options[:stored]
+                sql << (mariadb? ? " PERSISTENT" : " STORED")
+              end
+            end
 
-          if collation = options[:collation]
-            sql << " COLLATE #{collation}"
+            add_sql_comment!(super, options[:comment])
           end
 
-          add_sql_comment!(super, options[:comment])
-        end
+          def add_column_position!(sql, options)
+            if options[:first]
+              sql << " FIRST"
+            elsif options[:after]
+              sql << " AFTER #{quote_column_name(options[:after])}"
+            end
 
-        def add_column_position!(sql, options)
-          if options[:first]
-            sql << " FIRST"
-          elsif options[:after]
-            sql << " AFTER #{quote_column_name(options[:after])}"
+            sql
           end
 
-          sql
-        end
-
-        def index_in_create(table_name, column_name, options)
-          index_name, index_type, index_columns, _, _, index_using, comment = @conn.add_index_options(table_name, column_name, options)
-          add_sql_comment!("#{index_type} INDEX #{quote_column_name(index_name)} #{index_using} (#{index_columns})", comment)
-        end
+          def index_in_create(table_name, column_name, options)
+            index_name, index_type, index_columns, _, _, index_using, comment = @conn.add_index_options(table_name, column_name, options)
+            add_sql_comment!("#{index_type} INDEX #{quote_column_name(index_name)} #{index_using} (#{index_columns})".dup, comment)
+          end
       end
     end
   end
diff --git a/activerecord/lib/active_record/connection_adapters/mysql/schema_definitions.rb b/activerecord/lib/active_record/connection_adapters/mysql/schema_definitions.rb
index 157e75dbf7..2ed4ad16ae 100644
--- a/activerecord/lib/active_record/connection_adapters/mysql/schema_definitions.rb
+++ b/activerecord/lib/active_record/connection_adapters/mysql/schema_definitions.rb
@@ -1,12 +1,9 @@
+# frozen_string_literal: true
+
 module ActiveRecord
   module ConnectionAdapters
     module MySQL
       module ColumnMethods
-        def primary_key(name, type = :primary_key, **options)
-          options[:auto_increment] = true if type == :bigint && !options.key?(:default)
-          super
-        end
-
         def blob(*args, **options)
           args.each { |name| column(name, :blob, options) }
         end
@@ -35,10 +32,6 @@ module ActiveRecord
           args.each { |name| column(name, :longtext, options) }
         end
 
-        def json(*args, **options)
-          args.each { |name| column(name, :json, options) }
-        end
-
         def unsigned_integer(*args, **options)
           args.each { |name| column(name, :unsigned_integer, options) }
         end
@@ -56,33 +49,34 @@ module ActiveRecord
         end
       end
 
-      class ColumnDefinition < ActiveRecord::ConnectionAdapters::ColumnDefinition
-        attr_accessor :charset, :unsigned
-      end
-
       class TableDefinition < ActiveRecord::ConnectionAdapters::TableDefinition
         include ColumnMethods
 
-        def new_column_definition(name, type, options) # :nodoc:
-          column = super
-          case column.type
+        def new_column_definition(name, type, **options) # :nodoc:
+          case type
+          when :virtual
+            type = options[:type]
           when :primary_key
-            column.type = :integer
-            column.auto_increment = true
+            type = :integer
+            options[:limit] ||= 8
+            options[:primary_key] = true
           when /\Aunsigned_(?<type>.+)\z/
-            column.type = $~[:type].to_sym
-            column.unsigned = true
+            type = $~[:type].to_sym
+            options[:unsigned] = true
           end
-          column.unsigned ||= options[:unsigned]
-          column.charset = options[:charset]
-          column
+
+          super
         end
 
         private
+          def aliased_types(name, fallback)
+            fallback
+          end
 
-        def create_column_definition(name, type)
-          MySQL::ColumnDefinition.new(name, type)
-        end
+          def integer_like_primary_key_type(type, options)
+            options[:auto_increment] = true
+            type
+          end
       end
 
       class Table < ActiveRecord::ConnectionAdapters::Table
diff --git a/activerecord/lib/active_record/connection_adapters/mysql/schema_dumper.rb b/activerecord/lib/active_record/connection_adapters/mysql/schema_dumper.rb
index 2ba9657f24..d23178e43c 100644
--- a/activerecord/lib/active_record/connection_adapters/mysql/schema_dumper.rb
+++ b/activerecord/lib/active_record/connection_adapters/mysql/schema_dumper.rb
@@ -1,53 +1,79 @@
+# frozen_string_literal: true
+
 module ActiveRecord
   module ConnectionAdapters
     module MySQL
-      module ColumnDumper
-        def column_spec_for_primary_key(column)
-          if column.bigint?
-            spec = { id: :bigint.inspect }
-            spec[:default] = schema_default(column) || 'nil' unless column.auto_increment?
-          else
+      class SchemaDumper < ConnectionAdapters::SchemaDumper # :nodoc:
+        private
+          def prepare_column_options(column)
             spec = super
+            spec[:unsigned] = "true" if column.unsigned?
+            spec[:auto_increment] = "true" if column.auto_increment?
+
+            if @connection.supports_virtual_columns? && column.virtual?
+              spec[:as] = extract_expression_for_virtual_column(column)
+              spec[:stored] = "true" if /\b(?:STORED|PERSISTENT)\b/.match?(column.extra)
+              spec = { type: schema_type(column).inspect }.merge!(spec)
+            end
+
+            spec
           end
-          spec[:unsigned] = 'true' if column.unsigned?
-          spec
-        end
 
-        def prepare_column_options(column)
-          spec = super
-          spec[:unsigned] = 'true' if column.unsigned?
-          spec
-        end
+          def column_spec_for_primary_key(column)
+            spec = super
+            spec.delete(:auto_increment) if column.type == :integer && column.auto_increment?
+            spec
+          end
 
-        def migration_keys
-          super + [:unsigned]
-        end
+          def default_primary_key?(column)
+            super && column.auto_increment? && !column.unsigned?
+          end
 
-        private
+          def explicit_primary_key_default?(column)
+            column.type == :integer && !column.auto_increment?
+          end
 
-        def default_primary_key?(column)
-          super && column.auto_increment?
-        end
+          def schema_type(column)
+            case column.sql_type
+            when /\Atimestamp\b/
+              :timestamp
+            when "tinyblob"
+              :blob
+            else
+              super
+            end
+          end
 
-        def schema_type(column)
-          if column.sql_type == 'tinyblob'
-            :blob
-          else
-            super
+          def schema_precision(column)
+            super unless /\A(?:date)?time(?:stamp)?\b/.match?(column.sql_type) && column.precision == 0
           end
-        end
 
-        def schema_precision(column)
-          super unless /time/ === column.sql_type && column.precision == 0
-        end
+          def schema_collation(column)
+            if column.collation && table_name = column.table_name
+              @table_collation_cache ||= {}
+              @table_collation_cache[table_name] ||=
+                @connection.exec_query("SHOW TABLE STATUS LIKE #{@connection.quote(table_name)}", "SCHEMA").first["Collation"]
+              column.collation.inspect if column.collation != @table_collation_cache[table_name]
+            end
+          end
 
-        def schema_collation(column)
-          if column.collation && table_name = column.table_name
-            @table_collation_cache ||= {}
-            @table_collation_cache[table_name] ||= select_one("SHOW TABLE STATUS LIKE '#{table_name}'")["Collation"]
-            column.collation.inspect if column.collation != @table_collation_cache[table_name]
+          def extract_expression_for_virtual_column(column)
+            if @connection.mariadb? && @connection.version < "10.2.5"
+              create_table_info = @connection.send(:create_table_info, column.table_name)
+              column_name = @connection.quote_column_name(column.name)
+              if %r/#{column_name} #{Regexp.quote(column.sql_type)}(?: COLLATE \w+)? AS \((?<expression>.+?)\) #{column.extra}/ =~ create_table_info
+                $~[:expression].inspect
+              end
+            else
+              scope = @connection.send(:quoted_scope, column.table_name)
+              column_name = @connection.quote(column.name)
+              sql = "SELECT generation_expression FROM information_schema.columns" \
+                    " WHERE table_schema = #{scope[:schema]}" \
+                    "   AND table_name = #{scope[:name]}" \
+                    "   AND column_name = #{column_name}"
+              @connection.query_value(sql, "SCHEMA").inspect
+            end
           end
-        end
       end
     end
   end
diff --git a/activerecord/lib/active_record/connection_adapters/mysql/schema_statements.rb b/activerecord/lib/active_record/connection_adapters/mysql/schema_statements.rb
new file mode 100644
index 0000000000..ce50590651
--- /dev/null
+++ b/activerecord/lib/active_record/connection_adapters/mysql/schema_statements.rb
@@ -0,0 +1,148 @@
+# frozen_string_literal: true
+
+module ActiveRecord
+  module ConnectionAdapters
+    module MySQL
+      module SchemaStatements # :nodoc:
+        # Returns an array of indexes for the given table.
+        def indexes(table_name)
+          indexes = []
+          current_index = nil
+          execute_and_free("SHOW KEYS FROM #{quote_table_name(table_name)}", "SCHEMA") do |result|
+            each_hash(result) do |row|
+              if current_index != row[:Key_name]
+                next if row[:Key_name] == "PRIMARY" # skip the primary key
+                current_index = row[:Key_name]
+
+                mysql_index_type = row[:Index_type].downcase.to_sym
+                case mysql_index_type
+                when :fulltext, :spatial
+                  index_type = mysql_index_type
+                when :btree, :hash
+                  index_using = mysql_index_type
+                end
+
+                indexes << [
+                  row[:Table],
+                  row[:Key_name],
+                  row[:Non_unique].to_i == 0,
+                  [],
+                  lengths: {},
+                  orders: {},
+                  type: index_type,
+                  using: index_using,
+                  comment: row[:Index_comment].presence
+                ]
+              end
+
+              indexes.last[-2] << row[:Column_name]
+              indexes.last[-1][:lengths].merge!(row[:Column_name] => row[:Sub_part].to_i) if row[:Sub_part]
+              indexes.last[-1][:orders].merge!(row[:Column_name] => :desc) if row[:Collation] == "D"
+            end
+          end
+
+          indexes.map { |index| IndexDefinition.new(*index) }
+        end
+
+        def remove_column(table_name, column_name, type = nil, options = {})
+          if foreign_key_exists?(table_name, column: column_name)
+            remove_foreign_key(table_name, column: column_name)
+          end
+          super
+        end
+
+        def internal_string_options_for_primary_key
+          super.tap do |options|
+            if CHARSETS_OF_4BYTES_MAXLEN.include?(charset) && (mariadb? || version < "8.0.0")
+              options[:collation] = collation.sub(/\A[^_]+/, "utf8")
+            end
+          end
+        end
+
+        def update_table_definition(table_name, base)
+          MySQL::Table.new(table_name, base)
+        end
+
+        def create_schema_dumper(options)
+          MySQL::SchemaDumper.create(self, options)
+        end
+
+        private
+          CHARSETS_OF_4BYTES_MAXLEN = ["utf8mb4", "utf16", "utf16le", "utf32"]
+
+          def schema_creation
+            MySQL::SchemaCreation.new(self)
+          end
+
+          def create_table_definition(*args)
+            MySQL::TableDefinition.new(*args)
+          end
+
+          def new_column_from_field(table_name, field)
+            type_metadata = fetch_type_metadata(field[:Type], field[:Extra])
+            if type_metadata.type == :datetime && /\ACURRENT_TIMESTAMP(?:\(\))?\z/i.match?(field[:Default])
+              default, default_function = nil, "CURRENT_TIMESTAMP"
+            else
+              default, default_function = field[:Default], nil
+            end
+
+            MySQL::Column.new(
+              field[:Field],
+              default,
+              type_metadata,
+              field[:Null] == "YES",
+              table_name,
+              default_function,
+              field[:Collation],
+              comment: field[:Comment].presence
+            )
+          end
+
+          def fetch_type_metadata(sql_type, extra = "")
+            MySQL::TypeMetadata.new(super(sql_type), extra: extra)
+          end
+
+          def extract_foreign_key_action(specifier)
+            super unless specifier == "RESTRICT"
+          end
+
+          def add_index_length(quoted_columns, **options)
+            lengths = options_for_index_columns(options[:length])
+            quoted_columns.each do |name, column|
+              column << "(#{lengths[name]})" if lengths[name].present?
+            end
+          end
+
+          def add_options_for_index_columns(quoted_columns, **options)
+            quoted_columns = add_index_length(quoted_columns, options)
+            super
+          end
+
+          def data_source_sql(name = nil, type: nil)
+            scope = quoted_scope(name, type: type)
+
+            sql = "SELECT table_name FROM information_schema.tables".dup
+            sql << " WHERE table_schema = #{scope[:schema]}"
+            sql << " AND table_name = #{scope[:name]}" if scope[:name]
+            sql << " AND table_type = #{scope[:type]}" if scope[:type]
+            sql
+          end
+
+          def quoted_scope(name = nil, type: nil)
+            schema, name = extract_schema_qualified_name(name)
+            scope = {}
+            scope[:schema] = schema ? quote(schema) : "database()"
+            scope[:name] = quote(name) if name
+            scope[:type] = quote(type) if type
+            scope
+          end
+
+          def extract_schema_qualified_name(string)
+            schema, name = string.to_s.scan(/[^`.\s]+|`[^`]*`/)
+            schema, name = nil, schema unless name
+            [schema, name]
+          end
+      end
+    end
+  end
+end
diff --git a/activerecord/lib/active_record/connection_adapters/mysql/type_metadata.rb b/activerecord/lib/active_record/connection_adapters/mysql/type_metadata.rb
index e1e3f7b472..7ad0944d51 100644
--- a/activerecord/lib/active_record/connection_adapters/mysql/type_metadata.rb
+++ b/activerecord/lib/active_record/connection_adapters/mysql/type_metadata.rb
@@ -1,14 +1,17 @@
+# frozen_string_literal: true
+
 module ActiveRecord
   module ConnectionAdapters
     module MySQL
       class TypeMetadata < DelegateClass(SqlTypeMetadata) # :nodoc:
-        attr_reader :extra, :strict
+        undef to_yaml if method_defined?(:to_yaml)
+
+        attr_reader :extra
 
-        def initialize(type_metadata, extra: "", strict: false)
+        def initialize(type_metadata, extra: "")
           super(type_metadata)
           @type_metadata = type_metadata
           @extra = extra
-          @strict = strict
         end
 
         def ==(other)
@@ -23,9 +26,9 @@ module ActiveRecord
 
         protected
 
-        def attributes_for_hash
-          [self.class, @type_metadata, extra, strict]
-        end
+          def attributes_for_hash
+            [self.class, @type_metadata, extra]
+          end
       end
     end
   end
diff --git a/activerecord/lib/active_record/connection_adapters/mysql2_adapter.rb b/activerecord/lib/active_record/connection_adapters/mysql2_adapter.rb
index 22d35f1db5..bfdc7995f0 100644
--- a/activerecord/lib/active_record/connection_adapters/mysql2_adapter.rb
+++ b/activerecord/lib/active_record/connection_adapters/mysql2_adapter.rb
@@ -1,25 +1,22 @@
-require 'active_record/connection_adapters/abstract_mysql_adapter'
-require 'active_record/connection_adapters/mysql/database_statements'
+# frozen_string_literal: true
 
-gem 'mysql2', '>= 0.3.18', '< 0.5'
-require 'mysql2'
-raise 'mysql2 0.4.3 is not supported. Please upgrade to 0.4.4+' if Mysql2::VERSION == '0.4.3'
+require "active_record/connection_adapters/abstract_mysql_adapter"
+require "active_record/connection_adapters/mysql/database_statements"
+
+gem "mysql2", "~> 0.4.4"
+require "mysql2"
 
 module ActiveRecord
   module ConnectionHandling # :nodoc:
     # Establishes a connection to the database that's used by all Active Record objects.
     def mysql2_connection(config)
       config = config.symbolize_keys
-
-      config[:username] = 'root' if config[:username].nil?
       config[:flags] ||= 0
 
-      if Mysql2::Client.const_defined? :FOUND_ROWS
-        if config[:flags].kind_of? Array
-          config[:flags].push "FOUND_ROWS".freeze
-        else
-          config[:flags] |= Mysql2::Client::FOUND_ROWS
-        end
+      if config[:flags].kind_of? Array
+        config[:flags].push "FOUND_ROWS".freeze
+      else
+        config[:flags] |= Mysql2::Client::FOUND_ROWS
       end
 
       client = Mysql2::Client.new(config)
@@ -35,7 +32,7 @@ module ActiveRecord
 
   module ConnectionAdapters
     class Mysql2Adapter < AbstractMysqlAdapter
-      ADAPTER_NAME = 'Mysql2'.freeze
+      ADAPTER_NAME = "Mysql2".freeze
 
       include MySQL::DatabaseStatements
 
@@ -46,7 +43,7 @@ module ActiveRecord
       end
 
       def supports_json?
-        !mariadb? && version >= '5.7.8'
+        !mariadb? && version >= "5.7.8"
       end
 
       def supports_comments?
@@ -65,7 +62,7 @@ module ActiveRecord
 
       def each_hash(result) # :nodoc:
         if block_given?
-          result.each(:as => :hash, :symbolize_keys => true) do |row|
+          result.each(as: :hash, symbolize_keys: true) do |row|
             yield row
           end
         else
@@ -90,7 +87,6 @@ module ActiveRecord
       #++
 
       def active?
-        return false unless @connection
         @connection.ping
       end
 
@@ -105,27 +101,29 @@ module ActiveRecord
       # Otherwise, this method does nothing.
       def disconnect!
         super
-        unless @connection.nil?
-          @connection.close
-          @connection = nil
-        end
+        @connection.close
+      end
+
+      def discard! # :nodoc:
+        @connection.automatic_close = false
+        @connection = nil
       end
 
       private
 
-      def connect
-        @connection = Mysql2::Client.new(@config)
-        configure_connection
-      end
+        def connect
+          @connection = Mysql2::Client.new(@config)
+          configure_connection
+        end
 
-      def configure_connection
-        @connection.query_options.merge!(:as => :array)
-        super
-      end
+        def configure_connection
+          @connection.query_options.merge!(as: :array)
+          super
+        end
 
-      def full_version
-        @full_version ||= @connection.server_info[:version]
-      end
+        def full_version
+          @full_version ||= @connection.server_info[:version]
+        end
     end
   end
 end
diff --git a/activerecord/lib/active_record/connection_adapters/postgresql/column.rb b/activerecord/lib/active_record/connection_adapters/postgresql/column.rb
index 3ad1911a28..469ef3f5a0 100644
--- a/activerecord/lib/active_record/connection_adapters/postgresql/column.rb
+++ b/activerecord/lib/active_record/connection_adapters/postgresql/column.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActiveRecord
   module ConnectionAdapters
     # PostgreSQL-specific extensions to column definitions in a table.
@@ -5,11 +7,38 @@ module ActiveRecord
       delegate :array, :oid, :fmod, to: :sql_type_metadata
       alias :array? :array
 
+      def initialize(*, max_identifier_length: 63, **)
+        super
+        @max_identifier_length = max_identifier_length
+      end
+
       def serial?
         return unless default_function
 
-        %r{\Anextval\('"?#{table_name}_#{name}_seq"?'::regclass\)\z} === default_function
+        if %r{\Anextval\('"?(?<sequence_name>.+_(?<suffix>seq\d*))"?'::regclass\)\z} =~ default_function
+          sequence_name_from_parts(table_name, name, suffix) == sequence_name
+        end
       end
+
+      protected
+        attr_reader :max_identifier_length
+
+      private
+        def sequence_name_from_parts(table_name, column_name, suffix)
+          over_length = [table_name, column_name, suffix].map(&:length).sum + 2 - max_identifier_length
+
+          if over_length > 0
+            column_name_length = [(max_identifier_length - suffix.length - 2) / 2, column_name.length].min
+            over_length -= column_name.length - column_name_length
+            column_name = column_name[0, column_name_length - [over_length, 0].min]
+          end
+
+          if over_length > 0
+            table_name = table_name[0, table_name.length - over_length]
+          end
+
+          "#{table_name}_#{column_name}_#{suffix}"
+        end
     end
   end
 end
diff --git a/activerecord/lib/active_record/connection_adapters/postgresql/database_statements.rb b/activerecord/lib/active_record/connection_adapters/postgresql/database_statements.rb
index 6f2e03b370..8db2a645af 100644
--- a/activerecord/lib/active_record/connection_adapters/postgresql/database_statements.rb
+++ b/activerecord/lib/active_record/connection_adapters/postgresql/database_statements.rb
@@ -1,38 +1,12 @@
+# frozen_string_literal: true
+
 module ActiveRecord
   module ConnectionAdapters
     module PostgreSQL
       module DatabaseStatements
         def explain(arel, binds = [])
           sql = "EXPLAIN #{to_sql(arel, binds)}"
-          PostgreSQL::ExplainPrettyPrinter.new.pp(exec_query(sql, 'EXPLAIN', binds))
-        end
-
-        def select_value(arel, name = nil, binds = [])
-          arel, binds = binds_from_relation arel, binds
-          sql = to_sql(arel, binds)
-          execute_and_clear(sql, name, binds) do |result|
-            result.getvalue(0, 0) if result.ntuples > 0 && result.nfields > 0
-          end
-        end
-
-        def select_values(arel, name = nil, binds = [])
-          arel, binds = binds_from_relation arel, binds
-          sql = to_sql(arel, binds)
-          execute_and_clear(sql, name, binds) do |result|
-            if result.nfields > 0
-              result.column_values(0)
-            else
-              []
-            end
-          end
-        end
-
-        # Executes a SELECT query and returns an array of rows. Each row is an
-        # array of field values.
-        def select_rows(sql, name = nil, binds = [])
-          execute_and_clear(sql, name, binds) do |result|
-            result.values
-          end
+          PostgreSQL::ExplainPrettyPrinter.new.pp(exec_query(sql, "EXPLAIN", binds))
         end
 
         # The internal PostgreSQL identifier of the money data type.
@@ -74,9 +48,9 @@ module ActiveRecord
               #  (2) $12.345.678,12
               case data
               when /^-?\D+[\d,]+\.\d{2}$/  # (1)
-                data.gsub!(/[^-\d.]/, '')
+                data.gsub!(/[^-\d.]/, "")
               when /^-?\D+[\d.]+,\d{2}$/  # (2)
-                data.gsub!(/[^-\d,]/, '').sub!(/,/, '.')
+                data.gsub!(/[^-\d,]/, "").sub!(/,/, ".")
               end
             end
           end
@@ -85,21 +59,25 @@ module ActiveRecord
         # Queries the database and returns the results in an Array-like object
         def query(sql, name = nil) #:nodoc:
           log(sql, name) do
-            result_as_array @connection.async_exec(sql)
+            ActiveSupport::Dependencies.interlock.permit_concurrent_loads do
+              result_as_array @connection.async_exec(sql)
+            end
           end
         end
 
-        # Executes an SQL statement, returning a PGresult object on success
-        # or raising a PGError exception otherwise.
-        # Note: the PGresult object is manually memory managed; if you don't
-        # need it specifically, you many want consider the exec_query wrapper.
+        # Executes an SQL statement, returning a PG::Result object on success
+        # or raising a PG::Error exception otherwise.
+        # Note: the PG::Result object is manually memory managed; if you don't
+        # need it specifically, you may want consider the <tt>exec_query</tt> wrapper.
         def execute(sql, name = nil)
           log(sql, name) do
-            @connection.async_exec(sql)
+            ActiveSupport::Dependencies.interlock.permit_concurrent_loads do
+              @connection.async_exec(sql)
+            end
           end
         end
 
-        def exec_query(sql, name = 'SQL', binds = [], prepare: false)
+        def exec_query(sql, name = "SQL", binds = [], prepare: false)
           execute_and_clear(sql, name, binds, prepare: prepare) do |result|
             types = {}
             fields = result.fields
@@ -112,8 +90,8 @@ module ActiveRecord
           end
         end
 
-        def exec_delete(sql, name = 'SQL', binds = [])
-          execute_and_clear(sql, name, binds) {|result| result.cmd_tuples }
+        def exec_delete(sql, name = nil, binds = [])
+          execute_and_clear(sql, name, binds) { |result| result.cmd_tuples }
         end
         alias :exec_update :exec_delete
 
@@ -124,24 +102,29 @@ module ActiveRecord
             pk = primary_key(table_ref) if table_ref
           end
 
-          if pk && use_insert_returning?
+          if pk = suppress_composite_primary_key(pk)
             sql = "#{sql} RETURNING #{quote_column_name(pk)}"
           end
 
           super
         end
+        private :sql_for_insert
 
-        def exec_insert(sql, name, binds, pk = nil, sequence_name = nil)
-          val = exec_query(sql, name, binds)
-          if !use_insert_returning? && pk
+        def exec_insert(sql, name = nil, binds = [], pk = nil, sequence_name = nil)
+          if use_insert_returning? || pk == false
+            super
+          else
+            result = exec_query(sql, name, binds)
             unless sequence_name
               table_ref = extract_table_ref_from_insert_sql(sql)
-              sequence_name = default_sequence_name(table_ref, pk)
-              return val unless sequence_name
+              if table_ref
+                pk = primary_key(table_ref) if pk.nil?
+                pk = suppress_composite_primary_key(pk)
+                sequence_name = default_sequence_name(table_ref, pk)
+              end
+              return result unless sequence_name
             end
             last_insert_id_result(sequence_name)
-          else
-            val
           end
         end
 
@@ -164,6 +147,16 @@ module ActiveRecord
         def exec_rollback_db_transaction
           execute "ROLLBACK"
         end
+
+        private
+          # Returns the current ID of a table's sequence.
+          def last_insert_id_result(sequence_name)
+            exec_query("SELECT currval(#{quote(sequence_name)})", "SQL")
+          end
+
+          def suppress_composite_primary_key(pk)
+            pk unless pk.is_a?(Array)
+          end
       end
     end
   end
diff --git a/activerecord/lib/active_record/connection_adapters/postgresql/explain_pretty_printer.rb b/activerecord/lib/active_record/connection_adapters/postgresql/explain_pretty_printer.rb
index 789b88912c..086a5dcc15 100644
--- a/activerecord/lib/active_record/connection_adapters/postgresql/explain_pretty_printer.rb
+++ b/activerecord/lib/active_record/connection_adapters/postgresql/explain_pretty_printer.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActiveRecord
   module ConnectionAdapters
     module PostgreSQL
@@ -26,12 +28,12 @@ module ActiveRecord
           pp = []
 
           pp << header.center(width).rstrip
-          pp << '-' * width
+          pp << "-" * width
 
-          pp += lines.map {|line| " #{line}"}
+          pp += lines.map { |line| " #{line}" }
 
           nrows = result.rows.length
-          rows_label = nrows == 1 ? 'row' : 'rows'
+          rows_label = nrows == 1 ? "row" : "rows"
           pp << "(#{nrows} #{rows_label})"
 
           pp.join("\n") + "\n"
diff --git a/activerecord/lib/active_record/connection_adapters/postgresql/oid.rb b/activerecord/lib/active_record/connection_adapters/postgresql/oid.rb
index 68752cdd80..542ca75d3e 100644
--- a/activerecord/lib/active_record/connection_adapters/postgresql/oid.rb
+++ b/activerecord/lib/active_record/connection_adapters/postgresql/oid.rb
@@ -1,25 +1,27 @@
-require 'active_record/connection_adapters/postgresql/oid/array'
-require 'active_record/connection_adapters/postgresql/oid/bit'
-require 'active_record/connection_adapters/postgresql/oid/bit_varying'
-require 'active_record/connection_adapters/postgresql/oid/bytea'
-require 'active_record/connection_adapters/postgresql/oid/cidr'
-require 'active_record/connection_adapters/postgresql/oid/date_time'
-require 'active_record/connection_adapters/postgresql/oid/decimal'
-require 'active_record/connection_adapters/postgresql/oid/enum'
-require 'active_record/connection_adapters/postgresql/oid/hstore'
-require 'active_record/connection_adapters/postgresql/oid/inet'
-require 'active_record/connection_adapters/postgresql/oid/json'
-require 'active_record/connection_adapters/postgresql/oid/jsonb'
-require 'active_record/connection_adapters/postgresql/oid/money'
-require 'active_record/connection_adapters/postgresql/oid/point'
-require 'active_record/connection_adapters/postgresql/oid/rails_5_1_point'
-require 'active_record/connection_adapters/postgresql/oid/range'
-require 'active_record/connection_adapters/postgresql/oid/specialized_string'
-require 'active_record/connection_adapters/postgresql/oid/uuid'
-require 'active_record/connection_adapters/postgresql/oid/vector'
-require 'active_record/connection_adapters/postgresql/oid/xml'
+# frozen_string_literal: true
 
-require 'active_record/connection_adapters/postgresql/oid/type_map_initializer'
+require "active_record/connection_adapters/postgresql/oid/array"
+require "active_record/connection_adapters/postgresql/oid/bit"
+require "active_record/connection_adapters/postgresql/oid/bit_varying"
+require "active_record/connection_adapters/postgresql/oid/bytea"
+require "active_record/connection_adapters/postgresql/oid/cidr"
+require "active_record/connection_adapters/postgresql/oid/date_time"
+require "active_record/connection_adapters/postgresql/oid/decimal"
+require "active_record/connection_adapters/postgresql/oid/enum"
+require "active_record/connection_adapters/postgresql/oid/hstore"
+require "active_record/connection_adapters/postgresql/oid/inet"
+require "active_record/connection_adapters/postgresql/oid/jsonb"
+require "active_record/connection_adapters/postgresql/oid/money"
+require "active_record/connection_adapters/postgresql/oid/oid"
+require "active_record/connection_adapters/postgresql/oid/point"
+require "active_record/connection_adapters/postgresql/oid/legacy_point"
+require "active_record/connection_adapters/postgresql/oid/range"
+require "active_record/connection_adapters/postgresql/oid/specialized_string"
+require "active_record/connection_adapters/postgresql/oid/uuid"
+require "active_record/connection_adapters/postgresql/oid/vector"
+require "active_record/connection_adapters/postgresql/oid/xml"
+
+require "active_record/connection_adapters/postgresql/oid/type_map_initializer"
 
 module ActiveRecord
   module ConnectionAdapters
diff --git a/activerecord/lib/active_record/connection_adapters/postgresql/oid/array.rb b/activerecord/lib/active_record/connection_adapters/postgresql/oid/array.rb
index 87593ef704..d6852082ac 100644
--- a/activerecord/lib/active_record/connection_adapters/postgresql/oid/array.rb
+++ b/activerecord/lib/active_record/connection_adapters/postgresql/oid/array.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActiveRecord
   module ConnectionAdapters
     module PostgreSQL
@@ -5,10 +7,12 @@ module ActiveRecord
         class Array < Type::Value # :nodoc:
           include Type::Helpers::Mutable
 
+          Data = Struct.new(:encoder, :values) # :nodoc:
+
           attr_reader :subtype, :delimiter
-          delegate :type, :user_input_in_time_zone, :limit, to: :subtype
+          delegate :type, :user_input_in_time_zone, :limit, :precision, :scale, to: :subtype
 
-          def initialize(subtype, delimiter = ',')
+          def initialize(subtype, delimiter = ",")
             @subtype = subtype
             @delimiter = delimiter
 
@@ -17,8 +21,11 @@ module ActiveRecord
           end
 
           def deserialize(value)
-            if value.is_a?(::String)
+            case value
+            when ::String
               type_cast_array(@pg_decoder.decode(value), :deserialize)
+            when Data
+              type_cast_array(value.values, :deserialize)
             else
               super
             end
@@ -33,7 +40,8 @@ module ActiveRecord
 
           def serialize(value)
             if value.is_a?(::Array)
-              @pg_encoder.encode(type_cast_array(value, :serialize))
+              casted_values = type_cast_array(value, :serialize)
+              Data.new(@pg_encoder, casted_values)
             else
               super
             end
@@ -54,15 +62,19 @@ module ActiveRecord
             value.map(&block)
           end
 
+          def changed_in_place?(raw_old_value, new_value)
+            deserialize(raw_old_value) != new_value
+          end
+
           private
 
-          def type_cast_array(value, method)
-            if value.is_a?(::Array)
-              value.map { |item| type_cast_array(item, method) }
-            else
-              @subtype.public_send(method, value)
+            def type_cast_array(value, method)
+              if value.is_a?(::Array)
+                value.map { |item| type_cast_array(item, method) }
+              else
+                @subtype.public_send(method, value)
+              end
             end
-          end
         end
       end
     end
diff --git a/activerecord/lib/active_record/connection_adapters/postgresql/oid/bit.rb b/activerecord/lib/active_record/connection_adapters/postgresql/oid/bit.rb
index ea0fa2517f..587e95d192 100644
--- a/activerecord/lib/active_record/connection_adapters/postgresql/oid/bit.rb
+++ b/activerecord/lib/active_record/connection_adapters/postgresql/oid/bit.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActiveRecord
   module ConnectionAdapters
     module PostgreSQL
@@ -7,7 +9,7 @@ module ActiveRecord
             :bit
           end
 
-          def cast(value)
+          def cast_value(value)
             if ::String === value
               case value
               when /^0x/i
@@ -16,7 +18,7 @@ module ActiveRecord
                 value                    # Bit-string notation
               end
             else
-              value
+              value.to_s
             end
           end
 
@@ -34,16 +36,18 @@ module ActiveRecord
             end
 
             def binary?
-              /\A[01]*\Z/ === value
+              /\A[01]*\Z/.match?(value)
             end
 
             def hex?
-              /\A[0-9A-F]*\Z/i === value
+              /\A[0-9A-F]*\Z/i.match?(value)
             end
 
+            # TODO Change this to private once we've dropped Ruby 2.2 support.
+            # Workaround for Ruby 2.2 "private attribute?" warning.
             protected
 
-            attr_reader :value
+              attr_reader :value
           end
         end
       end
diff --git a/activerecord/lib/active_record/connection_adapters/postgresql/oid/bit_varying.rb b/activerecord/lib/active_record/connection_adapters/postgresql/oid/bit_varying.rb
index 4c21097d48..dc7079dda2 100644
--- a/activerecord/lib/active_record/connection_adapters/postgresql/oid/bit_varying.rb
+++ b/activerecord/lib/active_record/connection_adapters/postgresql/oid/bit_varying.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActiveRecord
   module ConnectionAdapters
     module PostgreSQL
diff --git a/activerecord/lib/active_record/connection_adapters/postgresql/oid/bytea.rb b/activerecord/lib/active_record/connection_adapters/postgresql/oid/bytea.rb
index 8f9d6e7f9b..a3c60ecef6 100644
--- a/activerecord/lib/active_record/connection_adapters/postgresql/oid/bytea.rb
+++ b/activerecord/lib/active_record/connection_adapters/postgresql/oid/bytea.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActiveRecord
   module ConnectionAdapters
     module PostgreSQL
@@ -6,7 +8,7 @@ module ActiveRecord
           def deserialize(value)
             return if value.nil?
             return value.to_s if value.is_a?(Type::Binary::Data)
-            PGconn.unescape_bytea(super)
+            PG::Connection.unescape_bytea(super)
           end
         end
       end
diff --git a/activerecord/lib/active_record/connection_adapters/postgresql/oid/cidr.rb b/activerecord/lib/active_record/connection_adapters/postgresql/oid/cidr.rb
index 838cb63281..66e99d9404 100644
--- a/activerecord/lib/active_record/connection_adapters/postgresql/oid/cidr.rb
+++ b/activerecord/lib/active_record/connection_adapters/postgresql/oid/cidr.rb
@@ -1,4 +1,6 @@
-require 'ipaddr'
+# frozen_string_literal: true
+
+require "ipaddr"
 
 module ActiveRecord
   module ConnectionAdapters
diff --git a/activerecord/lib/active_record/connection_adapters/postgresql/oid/date_time.rb b/activerecord/lib/active_record/connection_adapters/postgresql/oid/date_time.rb
index 424769f765..cd667422f5 100644
--- a/activerecord/lib/active_record/connection_adapters/postgresql/oid/date_time.rb
+++ b/activerecord/lib/active_record/connection_adapters/postgresql/oid/date_time.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActiveRecord
   module ConnectionAdapters
     module PostgreSQL
@@ -5,8 +7,8 @@ module ActiveRecord
         class DateTime < Type::DateTime # :nodoc:
           def cast_value(value)
             case value
-            when 'infinity' then ::Float::INFINITY
-            when '-infinity' then -::Float::INFINITY
+            when "infinity" then ::Float::INFINITY
+            when "-infinity" then -::Float::INFINITY
             when / BC$/
               astronomical_year = format("%04d", -value[/^\d+/].to_i + 1)
               super(value.sub(/ BC$/, "").sub(/^\d+/, astronomical_year))
diff --git a/activerecord/lib/active_record/connection_adapters/postgresql/oid/decimal.rb b/activerecord/lib/active_record/connection_adapters/postgresql/oid/decimal.rb
index 43d22c8daf..e7d33855c4 100644
--- a/activerecord/lib/active_record/connection_adapters/postgresql/oid/decimal.rb
+++ b/activerecord/lib/active_record/connection_adapters/postgresql/oid/decimal.rb
@@ -1,10 +1,12 @@
+# frozen_string_literal: true
+
 module ActiveRecord
   module ConnectionAdapters
     module PostgreSQL
       module OID # :nodoc:
         class Decimal < Type::Decimal # :nodoc:
           def infinity(options = {})
-            BigDecimal.new("Infinity") * (options[:negative] ? -1 : 1)
+            BigDecimal("Infinity") * (options[:negative] ? -1 : 1)
           end
         end
       end
diff --git a/activerecord/lib/active_record/connection_adapters/postgresql/oid/enum.rb b/activerecord/lib/active_record/connection_adapters/postgresql/oid/enum.rb
index 91d339f32c..f70f09ad95 100644
--- a/activerecord/lib/active_record/connection_adapters/postgresql/oid/enum.rb
+++ b/activerecord/lib/active_record/connection_adapters/postgresql/oid/enum.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActiveRecord
   module ConnectionAdapters
     module PostgreSQL
@@ -9,9 +11,9 @@ module ActiveRecord
 
           private
 
-          def cast_value(value)
-            value.to_s
-          end
+            def cast_value(value)
+              value.to_s
+            end
         end
       end
     end
diff --git a/activerecord/lib/active_record/connection_adapters/postgresql/oid/hstore.rb b/activerecord/lib/active_record/connection_adapters/postgresql/oid/hstore.rb
index 9270fc9f21..aabe83b85d 100644
--- a/activerecord/lib/active_record/connection_adapters/postgresql/oid/hstore.rb
+++ b/activerecord/lib/active_record/connection_adapters/postgresql/oid/hstore.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActiveRecord
   module ConnectionAdapters
     module PostgreSQL
@@ -12,8 +14,8 @@ module ActiveRecord
           def deserialize(value)
             if value.is_a?(::String)
               ::Hash[value.scan(HstorePair).map { |k, v|
-                v = v.upcase == 'NULL' ? nil : v.gsub(/\A"(.*)"\Z/m,'\1').gsub(/\\(.)/, '\1')
-                k = k.gsub(/\A"(.*)"\Z/m,'\1').gsub(/\\(.)/, '\1')
+                v = v.upcase == "NULL" ? nil : v.gsub(/\A"(.*)"\Z/m, '\1').gsub(/\\(.)/, '\1')
+                k = k.gsub(/\A"(.*)"\Z/m, '\1').gsub(/\\(.)/, '\1')
                 [k, v]
               }]
             else
@@ -23,7 +25,9 @@ module ActiveRecord
 
           def serialize(value)
             if value.is_a?(::Hash)
-              value.map { |k, v| "#{escape_hstore(k)}=>#{escape_hstore(v)}" }.join(', ')
+              value.map { |k, v| "#{escape_hstore(k)}=>#{escape_hstore(v)}" }.join(", ")
+            elsif value.respond_to?(:to_unsafe_h)
+              serialize(value.to_unsafe_h)
             else
               value
             end
@@ -33,25 +37,33 @@ module ActiveRecord
             ActiveRecord::Store::StringKeyedHashAccessor
           end
 
+          # Will compare the Hash equivalents of +raw_old_value+ and +new_value+.
+          # By comparing hashes, this avoids an edge case where the order of
+          # the keys change between the two hashes, and they would not be marked
+          # as equal.
+          def changed_in_place?(raw_old_value, new_value)
+            deserialize(raw_old_value) != new_value
+          end
+
           private
 
-          HstorePair = begin
-            quoted_string = /"[^"\\]*(?:\\.[^"\\]*)*"/
-            unquoted_string = /(?:\\.|[^\s,])[^\s=,\\]*(?:\\.[^\s=,\\]*|=[^,>])*/
-            /(#{quoted_string}|#{unquoted_string})\s*=>\s*(#{quoted_string}|#{unquoted_string})/
-          end
+            HstorePair = begin
+              quoted_string = /"[^"\\]*(?:\\.[^"\\]*)*"/
+              unquoted_string = /(?:\\.|[^\s,])[^\s=,\\]*(?:\\.[^\s=,\\]*|=[^,>])*/
+              /(#{quoted_string}|#{unquoted_string})\s*=>\s*(#{quoted_string}|#{unquoted_string})/
+            end
 
-          def escape_hstore(value)
-            if value.nil?
-              'NULL'
-            else
-              if value == ""
-                '""'
+            def escape_hstore(value)
+              if value.nil?
+                "NULL"
               else
-                '"%s"' % value.to_s.gsub(/(["\\])/, '\\\\\1')
+                if value == ""
+                  '""'
+                else
+                  '"%s"' % value.to_s.gsub(/(["\\])/, '\\\\\1')
+                end
               end
             end
-          end
         end
       end
     end
diff --git a/activerecord/lib/active_record/connection_adapters/postgresql/oid/inet.rb b/activerecord/lib/active_record/connection_adapters/postgresql/oid/inet.rb
index 96486fa65b..55be71fd26 100644
--- a/activerecord/lib/active_record/connection_adapters/postgresql/oid/inet.rb
+++ b/activerecord/lib/active_record/connection_adapters/postgresql/oid/inet.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActiveRecord
   module ConnectionAdapters
     module PostgreSQL
diff --git a/activerecord/lib/active_record/connection_adapters/postgresql/oid/jsonb.rb b/activerecord/lib/active_record/connection_adapters/postgresql/oid/jsonb.rb
index 87391b5dc7..e0216f1089 100644
--- a/activerecord/lib/active_record/connection_adapters/postgresql/oid/jsonb.rb
+++ b/activerecord/lib/active_record/connection_adapters/postgresql/oid/jsonb.rb
@@ -1,21 +1,13 @@
+# frozen_string_literal: true
+
 module ActiveRecord
   module ConnectionAdapters
     module PostgreSQL
       module OID # :nodoc:
-        class Jsonb < Json # :nodoc:
+        class Jsonb < Type::Json # :nodoc:
           def type
             :jsonb
           end
-
-          def changed_in_place?(raw_old_value, new_value)
-            # Postgres does not preserve insignificant whitespaces when
-            # round-tripping jsonb columns. This causes some false positives for
-            # the comparison here. Therefore, we need to parse and re-dump the
-            # raw value here to ensure the insignificant whitespaces are
-            # consistent with our encoder's output.
-            raw_old_value = serialize(deserialize(raw_old_value))
-            super(raw_old_value, new_value)
-          end
         end
       end
     end
diff --git a/activerecord/lib/active_record/connection_adapters/postgresql/oid/legacy_point.rb b/activerecord/lib/active_record/connection_adapters/postgresql/oid/legacy_point.rb
new file mode 100644
index 0000000000..7b057a8452
--- /dev/null
+++ b/activerecord/lib/active_record/connection_adapters/postgresql/oid/legacy_point.rb
@@ -0,0 +1,45 @@
+# frozen_string_literal: true
+
+module ActiveRecord
+  module ConnectionAdapters
+    module PostgreSQL
+      module OID # :nodoc:
+        class LegacyPoint < Type::Value # :nodoc:
+          include Type::Helpers::Mutable
+
+          def type
+            :point
+          end
+
+          def cast(value)
+            case value
+            when ::String
+              if value[0] == "(" && value[-1] == ")"
+                value = value[1...-1]
+              end
+              cast(value.split(","))
+            when ::Array
+              value.map { |v| Float(v) }
+            else
+              value
+            end
+          end
+
+          def serialize(value)
+            if value.is_a?(::Array)
+              "(#{number_for_point(value[0])},#{number_for_point(value[1])})"
+            else
+              super
+            end
+          end
+
+          private
+
+            def number_for_point(number)
+              number.to_s.gsub(/\.0$/, "")
+            end
+        end
+      end
+    end
+  end
+end
diff --git a/activerecord/lib/active_record/connection_adapters/postgresql/oid/money.rb b/activerecord/lib/active_record/connection_adapters/postgresql/oid/money.rb
index dcc12ae2a4..6434377b57 100644
--- a/activerecord/lib/active_record/connection_adapters/postgresql/oid/money.rb
+++ b/activerecord/lib/active_record/connection_adapters/postgresql/oid/money.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActiveRecord
   module ConnectionAdapters
     module PostgreSQL
@@ -22,12 +24,12 @@ module ActiveRecord
             #  (3) -$2.55
             #  (4) ($2.55)
 
-            value.sub!(/^\((.+)\)$/, '-\1') # (4)
+            value = value.sub(/^\((.+)\)$/, '-\1') # (4)
             case value
             when /^-?\D+[\d,]+\.\d{2}$/  # (1)
-              value.gsub!(/[^-\d.]/, '')
+              value.gsub!(/[^-\d.]/, "")
             when /^-?\D+[\d.]+,\d{2}$/  # (2)
-              value.gsub!(/[^-\d,]/, '').sub!(/,/, '.')
+              value.gsub!(/[^-\d,]/, "").sub!(/,/, ".")
             end
 
             super(value)
diff --git a/activerecord/lib/active_record/connection_adapters/postgresql/oid/json.rb b/activerecord/lib/active_record/connection_adapters/postgresql/oid/oid.rb
index dbc879ffd4..d8c044320d 100644
--- a/activerecord/lib/active_record/connection_adapters/postgresql/oid/json.rb
+++ b/activerecord/lib/active_record/connection_adapters/postgresql/oid/oid.rb
@@ -1,8 +1,13 @@
+# frozen_string_literal: true
+
 module ActiveRecord
   module ConnectionAdapters
     module PostgreSQL
       module OID # :nodoc:
-        class Json < Type::Internal::AbstractJson
+        class Oid < Type::Integer # :nodoc:
+          def type
+            :oid
+          end
         end
       end
     end
diff --git a/activerecord/lib/active_record/connection_adapters/postgresql/oid/point.rb b/activerecord/lib/active_record/connection_adapters/postgresql/oid/point.rb
index bf565bcf47..02a9c506f6 100644
--- a/activerecord/lib/active_record/connection_adapters/postgresql/oid/point.rb
+++ b/activerecord/lib/active_record/connection_adapters/postgresql/oid/point.rb
@@ -1,4 +1,8 @@
+# frozen_string_literal: true
+
 module ActiveRecord
+  Point = Struct.new(:x, :y)
+
   module ConnectionAdapters
     module PostgreSQL
       module OID # :nodoc:
@@ -12,20 +16,34 @@ module ActiveRecord
           def cast(value)
             case value
             when ::String
-              if value[0] == '(' && value[-1] == ')'
+              return if value.blank?
+
+              if value[0] == "(" && value[-1] == ")"
                 value = value[1...-1]
               end
-              cast(value.split(','))
+              x, y = value.split(",")
+              build_point(x, y)
             when ::Array
-              value.map { |v| Float(v) }
+              build_point(*value)
             else
               value
             end
           end
 
           def serialize(value)
-            if value.is_a?(::Array)
-              "(#{number_for_point(value[0])},#{number_for_point(value[1])})"
+            case value
+            when ActiveRecord::Point
+              "(#{number_for_point(value.x)},#{number_for_point(value.y)})"
+            when ::Array
+              serialize(build_point(*value))
+            else
+              super
+            end
+          end
+
+          def type_cast_for_schema(value)
+            if ActiveRecord::Point === value
+              [value.x, value.y]
             else
               super
             end
@@ -33,9 +51,13 @@ module ActiveRecord
 
           private
 
-          def number_for_point(number)
-            number.to_s.gsub(/\.0$/, '')
-          end
+            def number_for_point(number)
+              number.to_s.gsub(/\.0$/, "")
+            end
+
+            def build_point(x, y)
+              ActiveRecord::Point.new(Float(x), Float(y))
+            end
         end
       end
     end
diff --git a/activerecord/lib/active_record/connection_adapters/postgresql/oid/rails_5_1_point.rb b/activerecord/lib/active_record/connection_adapters/postgresql/oid/rails_5_1_point.rb
deleted file mode 100644
index 4da240edb2..0000000000
--- a/activerecord/lib/active_record/connection_adapters/postgresql/oid/rails_5_1_point.rb
+++ /dev/null
@@ -1,52 +0,0 @@
-module ActiveRecord
-  Point = Struct.new(:x, :y)
-
-  module ConnectionAdapters
-    module PostgreSQL
-      module OID # :nodoc:
-        class Rails51Point < Type::Value # :nodoc:
-          include Type::Helpers::Mutable
-
-          def type
-            :point
-          end
-
-          def cast(value)
-            case value
-            when ::String
-              return if value.blank?
-              
-              if value[0] == '(' && value[-1] == ')'
-                value = value[1...-1]
-              end
-              x, y = value.split(",")
-              build_point(x, y)
-            when ::Array
-              build_point(*value)
-            else
-              value
-            end
-          end
-
-          def serialize(value)
-            if value.is_a?(ActiveRecord::Point)
-              "(#{number_for_point(value.x)},#{number_for_point(value.y)})"
-            else
-              super
-            end
-          end
-
-          private
-
-          def number_for_point(number)
-            number.to_s.gsub(/\.0$/, '')
-          end
-
-          def build_point(x, y)
-            ActiveRecord::Point.new(Float(x), Float(y))
-          end
-        end
-      end
-    end
-  end
-end
diff --git a/activerecord/lib/active_record/connection_adapters/postgresql/oid/range.rb b/activerecord/lib/active_record/connection_adapters/postgresql/oid/range.rb
index a8d2310035..a89aa5ea09 100644
--- a/activerecord/lib/active_record/connection_adapters/postgresql/oid/range.rb
+++ b/activerecord/lib/active_record/connection_adapters/postgresql/oid/range.rb
@@ -1,4 +1,4 @@
-require 'active_support/core_ext/string/filters'
+# frozen_string_literal: true
 
 module ActiveRecord
   module ConnectionAdapters
@@ -14,11 +14,11 @@ module ActiveRecord
           end
 
           def type_cast_for_schema(value)
-            value.inspect.gsub('Infinity', '::Float::INFINITY')
+            value.inspect.gsub("Infinity", "::Float::INFINITY")
           end
 
           def cast_value(value)
-            return if value == 'empty'
+            return if value == "empty"
             return value unless value.is_a?(::String)
 
             extracted = extract_bounds(value)
@@ -35,7 +35,7 @@ module ActiveRecord
             if value.is_a?(::Range)
               from = type_cast_single_for_database(value.begin)
               to = type_cast_single_for_database(value.end)
-              "[#{from},#{to}#{value.exclude_end? ? ')' : ']'}"
+              ::Range.new(from, to, value.exclude_end?)
             else
               super
             end
@@ -55,37 +55,37 @@ module ActiveRecord
 
           private
 
-          def type_cast_single(value)
-            infinity?(value) ? value : @subtype.deserialize(value)
-          end
+            def type_cast_single(value)
+              infinity?(value) ? value : @subtype.deserialize(value)
+            end
 
-          def type_cast_single_for_database(value)
-            infinity?(value) ? '' : @subtype.serialize(value)
-          end
+            def type_cast_single_for_database(value)
+              infinity?(value) ? "" : @subtype.serialize(value)
+            end
 
-          def extract_bounds(value)
-            from, to = value[1..-2].split(',')
-            {
-              from:          (value[1] == ',' || from == '-infinity') ? infinity(negative: true) : from,
-              to:            (value[-2] == ',' || to == 'infinity') ? infinity : to,
-              exclude_start: (value[0] == '('),
-              exclude_end:   (value[-1] == ')')
-            }
-          end
+            def extract_bounds(value)
+              from, to = value[1..-2].split(",")
+              {
+                from:          (value[1] == "," || from == "-infinity") ? infinity(negative: true) : from,
+                to:            (value[-2] == "," || to == "infinity") ? infinity : to,
+                exclude_start: (value[0] == "("),
+                exclude_end:   (value[-1] == ")")
+              }
+            end
 
-          def infinity(negative: false)
-            if subtype.respond_to?(:infinity)
-              subtype.infinity(negative: negative)
-            elsif negative
-              -::Float::INFINITY
-            else
-              ::Float::INFINITY
+            def infinity(negative: false)
+              if subtype.respond_to?(:infinity)
+                subtype.infinity(negative: negative)
+              elsif negative
+                -::Float::INFINITY
+              else
+                ::Float::INFINITY
+              end
             end
-          end
 
-          def infinity?(value)
-            value.respond_to?(:infinite?) && value.infinite?
-          end
+            def infinity?(value)
+              value.respond_to?(:infinite?) && value.infinite?
+            end
         end
       end
     end
diff --git a/activerecord/lib/active_record/connection_adapters/postgresql/oid/specialized_string.rb b/activerecord/lib/active_record/connection_adapters/postgresql/oid/specialized_string.rb
index 2d2fede4e8..4ad1344f05 100644
--- a/activerecord/lib/active_record/connection_adapters/postgresql/oid/specialized_string.rb
+++ b/activerecord/lib/active_record/connection_adapters/postgresql/oid/specialized_string.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActiveRecord
   module ConnectionAdapters
     module PostgreSQL
@@ -5,8 +7,9 @@ module ActiveRecord
         class SpecializedString < Type::String # :nodoc:
           attr_reader :type
 
-          def initialize(type)
+          def initialize(type, **options)
             @type = type
+            super(options)
           end
         end
       end
diff --git a/activerecord/lib/active_record/connection_adapters/postgresql/oid/type_map_initializer.rb b/activerecord/lib/active_record/connection_adapters/postgresql/oid/type_map_initializer.rb
index 6155e53632..231278c184 100644
--- a/activerecord/lib/active_record/connection_adapters/postgresql/oid/type_map_initializer.rb
+++ b/activerecord/lib/active_record/connection_adapters/postgresql/oid/type_map_initializer.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActiveRecord
   module ConnectionAdapters
     module PostgreSQL
@@ -13,13 +15,13 @@ module ActiveRecord
           end
 
           def run(records)
-            nodes = records.reject { |row| @store.key? row['oid'].to_i }
-            mapped, nodes = nodes.partition { |row| @store.key? row['typname'] }
-            ranges, nodes = nodes.partition { |row| row['typtype'] == 'r'.freeze }
-            enums, nodes = nodes.partition { |row| row['typtype'] == 'e'.freeze }
-            domains, nodes = nodes.partition { |row| row['typtype'] == 'd'.freeze }
-            arrays, nodes = nodes.partition { |row| row['typinput'] == 'array_in'.freeze }
-            composites, nodes = nodes.partition { |row| row['typelem'].to_i != 0 }
+            nodes = records.reject { |row| @store.key? row["oid"].to_i }
+            mapped, nodes = nodes.partition { |row| @store.key? row["typname"] }
+            ranges, nodes = nodes.partition { |row| row["typtype"] == "r".freeze }
+            enums, nodes = nodes.partition { |row| row["typtype"] == "e".freeze }
+            domains, nodes = nodes.partition { |row| row["typtype"] == "d".freeze }
+            arrays, nodes = nodes.partition { |row| row["typinput"] == "array_in".freeze }
+            composites, nodes = nodes.partition { |row| row["typelem"].to_i != 0 }
 
             mapped.each     { |row| register_mapped_type(row)    }
             enums.each      { |row| register_enum_type(row)      }
@@ -29,8 +31,8 @@ module ActiveRecord
             composites.each { |row| register_composite_type(row) }
           end
 
-          def query_conditions_for_initial_load(type_map)
-            known_type_names = type_map.keys.map { |n| "'#{n}'" }
+          def query_conditions_for_initial_load
+            known_type_names = @store.keys.map { |n| "'#{n}'" }
             known_type_types = %w('r' 'e' 'd')
             <<-SQL % [known_type_names.join(", "), known_type_types.join(", ")]
               WHERE
@@ -42,66 +44,66 @@ module ActiveRecord
           end
 
           private
-          def register_mapped_type(row)
-            alias_type row['oid'], row['typname']
-          end
+            def register_mapped_type(row)
+              alias_type row["oid"], row["typname"]
+            end
 
-          def register_enum_type(row)
-            register row['oid'], OID::Enum.new
-          end
+            def register_enum_type(row)
+              register row["oid"], OID::Enum.new
+            end
 
-          def register_array_type(row)
-            register_with_subtype(row['oid'], row['typelem'].to_i) do |subtype|
-              OID::Array.new(subtype, row['typdelim'])
+            def register_array_type(row)
+              register_with_subtype(row["oid"], row["typelem"].to_i) do |subtype|
+                OID::Array.new(subtype, row["typdelim"])
+              end
             end
-          end
 
-          def register_range_type(row)
-            register_with_subtype(row['oid'], row['rngsubtype'].to_i) do |subtype|
-              OID::Range.new(subtype, row['typname'].to_sym)
+            def register_range_type(row)
+              register_with_subtype(row["oid"], row["rngsubtype"].to_i) do |subtype|
+                OID::Range.new(subtype, row["typname"].to_sym)
+              end
             end
-          end
 
-          def register_domain_type(row)
-            if base_type = @store.lookup(row["typbasetype"].to_i)
-              register row['oid'], base_type
-            else
-              warn "unknown base type (OID: #{row["typbasetype"]}) for domain #{row["typname"]}."
+            def register_domain_type(row)
+              if base_type = @store.lookup(row["typbasetype"].to_i)
+                register row["oid"], base_type
+              else
+                warn "unknown base type (OID: #{row["typbasetype"]}) for domain #{row["typname"]}."
+              end
             end
-          end
 
-          def register_composite_type(row)
-            if subtype = @store.lookup(row['typelem'].to_i)
-              register row['oid'], OID::Vector.new(row['typdelim'], subtype)
+            def register_composite_type(row)
+              if subtype = @store.lookup(row["typelem"].to_i)
+                register row["oid"], OID::Vector.new(row["typdelim"], subtype)
+              end
             end
-          end
 
-          def register(oid, oid_type = nil, &block)
-            oid = assert_valid_registration(oid, oid_type || block)
-            if block_given?
-              @store.register_type(oid, &block)
-            else
-              @store.register_type(oid, oid_type)
+            def register(oid, oid_type = nil, &block)
+              oid = assert_valid_registration(oid, oid_type || block)
+              if block_given?
+                @store.register_type(oid, &block)
+              else
+                @store.register_type(oid, oid_type)
+              end
             end
-          end
 
-          def alias_type(oid, target)
-            oid = assert_valid_registration(oid, target)
-            @store.alias_type(oid, target)
-          end
+            def alias_type(oid, target)
+              oid = assert_valid_registration(oid, target)
+              @store.alias_type(oid, target)
+            end
 
-          def register_with_subtype(oid, target_oid)
-            if @store.key?(target_oid)
-              register(oid) do |_, *args|
-                yield @store.lookup(target_oid, *args)
+            def register_with_subtype(oid, target_oid)
+              if @store.key?(target_oid)
+                register(oid) do |_, *args|
+                  yield @store.lookup(target_oid, *args)
+                end
               end
             end
-          end
 
-          def assert_valid_registration(oid, oid_type)
-            raise ArgumentError, "can't register nil type for OID #{oid}" if oid_type.nil?
-            oid.to_i
-          end
+            def assert_valid_registration(oid, oid_type)
+              raise ArgumentError, "can't register nil type for OID #{oid}" if oid_type.nil?
+              oid.to_i
+            end
         end
       end
     end
diff --git a/activerecord/lib/active_record/connection_adapters/postgresql/oid/uuid.rb b/activerecord/lib/active_record/connection_adapters/postgresql/oid/uuid.rb
index 5e839228e9..bc9b8dbfcf 100644
--- a/activerecord/lib/active_record/connection_adapters/postgresql/oid/uuid.rb
+++ b/activerecord/lib/active_record/connection_adapters/postgresql/oid/uuid.rb
@@ -1,9 +1,11 @@
+# frozen_string_literal: true
+
 module ActiveRecord
   module ConnectionAdapters
     module PostgreSQL
       module OID # :nodoc:
         class Uuid < Type::Value # :nodoc:
-          ACCEPTABLE_UUID = %r{\A\{?([a-fA-F0-9]{4}-?){8}\}?\z}x
+          ACCEPTABLE_UUID = %r{\A(\{)?([a-fA-F0-9]{4}-?){8}(?(1)\}|)\z}
 
           alias_method :serialize, :deserialize
 
diff --git a/activerecord/lib/active_record/connection_adapters/postgresql/oid/vector.rb b/activerecord/lib/active_record/connection_adapters/postgresql/oid/vector.rb
index b26e876b54..88ef626a16 100644
--- a/activerecord/lib/active_record/connection_adapters/postgresql/oid/vector.rb
+++ b/activerecord/lib/active_record/connection_adapters/postgresql/oid/vector.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActiveRecord
   module ConnectionAdapters
     module PostgreSQL
diff --git a/activerecord/lib/active_record/connection_adapters/postgresql/oid/xml.rb b/activerecord/lib/active_record/connection_adapters/postgresql/oid/xml.rb
index d40d837cee..042f32fdc3 100644
--- a/activerecord/lib/active_record/connection_adapters/postgresql/oid/xml.rb
+++ b/activerecord/lib/active_record/connection_adapters/postgresql/oid/xml.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActiveRecord
   module ConnectionAdapters
     module PostgreSQL
diff --git a/activerecord/lib/active_record/connection_adapters/postgresql/quoting.rb b/activerecord/lib/active_record/connection_adapters/postgresql/quoting.rb
index 6414459cd1..9fdeab06c1 100644
--- a/activerecord/lib/active_record/connection_adapters/postgresql/quoting.rb
+++ b/activerecord/lib/active_record/connection_adapters/postgresql/quoting.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActiveRecord
   module ConnectionAdapters
     module PostgreSQL
@@ -28,12 +30,12 @@ module ActiveRecord
         # - "schema.name".table_name
         # - "schema.name"."table.name"
         def quote_table_name(name) # :nodoc:
-          @quoted_table_names[name] ||= Utils.extract_schema_qualified_name(name.to_s).quoted
+          @quoted_table_names[name] ||= Utils.extract_schema_qualified_name(name.to_s).quoted.freeze
         end
 
         # Quotes schema names for use in SQL queries.
         def quote_schema_name(name)
-          PGconn.quote_ident(name)
+          PG::Connection.quote_ident(name)
         end
 
         def quote_table_name_for_assignment(table, attr)
@@ -42,7 +44,7 @@ module ActiveRecord
 
         # Quotes column names for use in SQL queries.
         def quote_column_name(name) # :nodoc:
-          @quoted_column_names[name] ||= PGconn.quote_ident(super)
+          @quoted_column_names[name] ||= PG::Connection.quote_ident(super).freeze
         end
 
         # Quote date/time values for use in SQL input.
@@ -55,10 +57,14 @@ module ActiveRecord
           end
         end
 
+        def quoted_binary(value) # :nodoc:
+          "'#{escape_bytea(value.to_s)}'"
+        end
+
         def quote_default_expression(value, column) # :nodoc:
           if value.is_a?(Proc)
             value.call
-          elsif column.type == :uuid && value =~ /\(\)/
+          elsif column.type == :uuid && value.is_a?(String) && /\(\)/.match?(value)
             value # Does not quote function default values for UUID columns
           elsif column.respond_to?(:array?)
             value = type_cast_from_column(column, value)
@@ -73,43 +79,81 @@ module ActiveRecord
         end
 
         private
+          def lookup_cast_type(sql_type)
+            super(query_value("SELECT #{quote(sql_type)}::regtype::oid", "SCHEMA").to_i)
+          end
 
-        def _quote(value)
-          case value
-          when Type::Binary::Data
-            "'#{escape_bytea(value.to_s)}'"
-          when OID::Xml::Data
-            "xml '#{quote_string(value.to_s)}'"
-          when OID::Bit::Data
-            if value.binary?
-              "B'#{value}'"
-            elsif value.hex?
-              "X'#{value}'"
+          def _quote(value)
+            case value
+            when OID::Xml::Data
+              "xml '#{quote_string(value.to_s)}'"
+            when OID::Bit::Data
+              if value.binary?
+                "B'#{value}'"
+              elsif value.hex?
+                "X'#{value}'"
+              end
+            when Float
+              if value.infinite? || value.nan?
+                "'#{value}'"
+              else
+                super
+              end
+            when OID::Array::Data
+              _quote(encode_array(value))
+            when Range
+              _quote(encode_range(value))
+            else
+              super
             end
-          when Float
-            if value.infinite? || value.nan?
-              "'#{value}'"
+          end
+
+          def _type_cast(value)
+            case value
+            when Type::Binary::Data
+              # Return a bind param hash with format as binary.
+              # See https://deveiate.org/code/pg/PG/Connection.html#method-i-exec_prepared-doc
+              # for more information
+              { value: value.to_s, format: 1 }
+            when OID::Xml::Data, OID::Bit::Data
+              value.to_s
+            when OID::Array::Data
+              encode_array(value)
+            when Range
+              encode_range(value)
             else
               super
             end
-          else
-            super
           end
-        end
 
-        def _type_cast(value)
-          case value
-          when Type::Binary::Data
-            # Return a bind param hash with format as binary.
-            # See http://deveiate.org/code/pg/PGconn.html#method-i-exec_prepared-doc
-            # for more information
-            { value: value.to_s, format: 1 }
-          when OID::Xml::Data, OID::Bit::Data
-            value.to_s
-          else
-            super
+          def encode_array(array_data)
+            encoder = array_data.encoder
+            values = type_cast_array(array_data.values)
+
+            result = encoder.encode(values)
+            if encoding = determine_encoding_of_strings_in_array(values)
+              result.force_encoding(encoding)
+            end
+            result
+          end
+
+          def encode_range(range)
+            "[#{type_cast(range.first)},#{type_cast(range.last)}#{range.exclude_end? ? ')' : ']'}"
+          end
+
+          def determine_encoding_of_strings_in_array(value)
+            case value
+            when ::Array then determine_encoding_of_strings_in_array(value.first)
+            when ::String then value.encoding
+            end
+          end
+
+          def type_cast_array(values)
+            case values
+            when ::Array then values.map { |item| type_cast_array(item) }
+            else _type_cast(values)
+            end
           end
-        end
       end
     end
   end
diff --git a/activerecord/lib/active_record/connection_adapters/postgresql/referential_integrity.rb b/activerecord/lib/active_record/connection_adapters/postgresql/referential_integrity.rb
index 44a7338bf5..8df91c988b 100644
--- a/activerecord/lib/active_record/connection_adapters/postgresql/referential_integrity.rb
+++ b/activerecord/lib/active_record/connection_adapters/postgresql/referential_integrity.rb
@@ -1,27 +1,24 @@
+# frozen_string_literal: true
+
 module ActiveRecord
   module ConnectionAdapters
     module PostgreSQL
       module ReferentialIntegrity # :nodoc:
-        def supports_disable_referential_integrity? # :nodoc:
-          true
-        end
-
         def disable_referential_integrity # :nodoc:
-          if supports_disable_referential_integrity?
-            original_exception = nil
+          original_exception = nil
 
-            begin
-              transaction(requires_new: true) do
-                execute(tables.collect { |name| "ALTER TABLE #{quote_table_name(name)} DISABLE TRIGGER ALL" }.join(";"))
-              end
-            rescue ActiveRecord::ActiveRecordError => e
-              original_exception = e
+          begin
+            transaction(requires_new: true) do
+              execute(tables.collect { |name| "ALTER TABLE #{quote_table_name(name)} DISABLE TRIGGER ALL" }.join(";"))
             end
+          rescue ActiveRecord::ActiveRecordError => e
+            original_exception = e
+          end
 
-            begin
-              yield
-            rescue ActiveRecord::InvalidForeignKey => e
-              warn <<-WARNING
+          begin
+            yield
+          rescue ActiveRecord::InvalidForeignKey => e
+            warn <<-WARNING
 WARNING: Rails was not able to disable referential integrity.
 
 This is most likely caused due to missing permissions.
@@ -30,17 +27,14 @@ Rails needs superuser privileges to disable referential integrity.
     cause: #{original_exception.try(:message)}
 
               WARNING
-              raise e
-            end
+            raise e
+          end
 
-            begin
-              transaction(requires_new: true) do
-                execute(tables.collect { |name| "ALTER TABLE #{quote_table_name(name)} ENABLE TRIGGER ALL" }.join(";"))
-              end
-            rescue ActiveRecord::ActiveRecordError
+          begin
+            transaction(requires_new: true) do
+              execute(tables.collect { |name| "ALTER TABLE #{quote_table_name(name)} ENABLE TRIGGER ALL" }.join(";"))
             end
-          else
-            yield
+          rescue ActiveRecord::ActiveRecordError
           end
         end
       end
diff --git a/activerecord/lib/active_record/connection_adapters/postgresql/schema_creation.rb b/activerecord/lib/active_record/connection_adapters/postgresql/schema_creation.rb
new file mode 100644
index 0000000000..8e381a92cf
--- /dev/null
+++ b/activerecord/lib/active_record/connection_adapters/postgresql/schema_creation.rb
@@ -0,0 +1,29 @@
+# frozen_string_literal: true
+
+module ActiveRecord
+  module ConnectionAdapters
+    module PostgreSQL
+      class SchemaCreation < AbstractAdapter::SchemaCreation # :nodoc:
+        private
+          def visit_AlterTable(o)
+            super << o.constraint_validations.map { |fk| visit_ValidateConstraint fk }.join(" ")
+          end
+
+          def visit_AddForeignKey(o)
+            super.dup.tap { |sql| sql << " NOT VALID" unless o.validate? }
+          end
+
+          def visit_ValidateConstraint(name)
+            "VALIDATE CONSTRAINT #{quote_column_name(name)}"
+          end
+
+          def add_column_options!(sql, options)
+            if options[:collation]
+              sql << " COLLATE \"#{options[:collation]}\""
+            end
+            super
+          end
+      end
+    end
+  end
+end
diff --git a/activerecord/lib/active_record/connection_adapters/postgresql/schema_definitions.rb b/activerecord/lib/active_record/connection_adapters/postgresql/schema_definitions.rb
index 6399bddbee..6047217fcd 100644
--- a/activerecord/lib/active_record/connection_adapters/postgresql/schema_definitions.rb
+++ b/activerecord/lib/active_record/connection_adapters/postgresql/schema_definitions.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActiveRecord
   module ConnectionAdapters
     module PostgreSQL
@@ -11,11 +13,22 @@ module ActiveRecord
         #     t.timestamps
         #   end
         #
-        # By default, this will use the +uuid_generate_v4()+ function from the
-        # +uuid-ossp+ extension, which MUST be enabled on your database. To enable
-        # the +uuid-ossp+ extension, you can use the +enable_extension+ method in your
-        # migrations. To use a UUID primary key without +uuid-ossp+ enabled, you can
-        # set the +:default+ option to +nil+:
+        # By default, this will use the +gen_random_uuid()+ function from the
+        # +pgcrypto+ extension. As that extension is only available in
+        # PostgreSQL 9.4+, for earlier versions an explicit default can be set
+        # to use +uuid_generate_v4()+ from the +uuid-ossp+ extension instead:
+        #
+        #   create_table :stuffs, id: false do |t|
+        #     t.primary_key :id, :uuid, default: "uuid_generate_v4()"
+        #     t.uuid :foo_id
+        #     t.timestamps
+        #   end
+        #
+        # To enable the appropriate extension, which is a requirement, use
+        # the +enable_extension+ method in your migrations.
+        #
+        # To use a UUID primary key without any of the extensions, set the
+        # +:default+ option to +nil+:
         #
         #   create_table :stuffs, id: false do |t|
         #     t.primary_key :id, :uuid, default: nil
@@ -23,15 +36,18 @@ module ActiveRecord
         #     t.timestamps
         #   end
         #
-        # You may also pass a different UUID generation function from +uuid-ossp+
-        # or another library.
+        # You may also pass a custom stored procedure that returns a UUID or use a
+        # different UUID generation function from another library.
         #
         # Note that setting the UUID primary key default value to +nil+ will
         # require you to assure that you always provide a UUID value before saving
         # a record (as primary keys cannot be +nil+). This might be done via the
         # +SecureRandom.uuid+ method and a +before_save+ callback, for instance.
         def primary_key(name, type = :primary_key, **options)
-          options[:default] = options.fetch(:default, 'uuid_generate_v4()') if type == :uuid
+          if type == :uuid
+            options[:default] = options.fetch(:default, "gen_random_uuid()")
+          end
+
           super
         end
 
@@ -67,6 +83,10 @@ module ActiveRecord
           args.each { |name| column(name, :inet, options) }
         end
 
+        def interval(*args, **options)
+          args.each { |name| column(name, :interval, options) }
+        end
+
         def int4range(*args, **options)
           args.each { |name| column(name, :int4range, options) }
         end
@@ -75,10 +95,6 @@ module ActiveRecord
           args.each { |name| column(name, :int8range, options) }
         end
 
-        def json(*args, **options)
-          args.each { |name| column(name, :json, options) }
-        end
-
         def jsonb(*args, **options)
           args.each { |name| column(name, :jsonb, options) }
         end
@@ -99,6 +115,10 @@ module ActiveRecord
           args.each { |name| column(name, :numrange, options) }
         end
 
+        def oid(*args, **options)
+          args.each { |name| column(name, :oid, options) }
+        end
+
         def point(*args, **options)
           args.each { |name| column(name, :point, options) }
         end
@@ -152,29 +172,35 @@ module ActiveRecord
         end
       end
 
-      class ColumnDefinition < ActiveRecord::ConnectionAdapters::ColumnDefinition
-        attr_accessor :array
-      end
-
       class TableDefinition < ActiveRecord::ConnectionAdapters::TableDefinition
         include ColumnMethods
 
-        def new_column_definition(name, type, options) # :nodoc:
-          column = super
-          column.array = options[:array]
-          column
-        end
-
         private
-
-          def create_column_definition(name, type)
-            PostgreSQL::ColumnDefinition.new name, type
+          def integer_like_primary_key_type(type, options)
+            if type == :bigint || options[:limit] == 8
+              :bigserial
+            else
+              :serial
+            end
           end
       end
 
       class Table < ActiveRecord::ConnectionAdapters::Table
         include ColumnMethods
       end
+
+      class AlterTable < ActiveRecord::ConnectionAdapters::AlterTable
+        attr_reader :constraint_validations
+
+        def initialize(td)
+          super
+          @constraint_validations = []
+        end
+
+        def validate_constraint(name)
+          @constraint_validations << name
+        end
+      end
     end
   end
 end
diff --git a/activerecord/lib/active_record/connection_adapters/postgresql/schema_dumper.rb b/activerecord/lib/active_record/connection_adapters/postgresql/schema_dumper.rb
index a1e10fd364..84643d20da 100644
--- a/activerecord/lib/active_record/connection_adapters/postgresql/schema_dumper.rb
+++ b/activerecord/lib/active_record/connection_adapters/postgresql/schema_dumper.rb
@@ -1,46 +1,49 @@
+# frozen_string_literal: true
+
 module ActiveRecord
   module ConnectionAdapters
     module PostgreSQL
-      module ColumnDumper
-        def column_spec_for_primary_key(column)
-          spec = super
-          if schema_type(column) == :uuid
-            spec[:default] ||= 'nil'
-          end
-          spec
-        end
+      class SchemaDumper < ConnectionAdapters::SchemaDumper # :nodoc:
+        private
 
-        # Adds +:array+ option to the default set
-        def prepare_column_options(column)
-          spec = super
-          spec[:array] = 'true' if column.array?
-          spec
-        end
+          def extensions(stream)
+            extensions = @connection.extensions
+            if extensions.any?
+              stream.puts "  # These are extensions that must be enabled in order to support this database"
+              extensions.sort.each do |extension|
+                stream.puts "  enable_extension #{extension.inspect}"
+              end
+              stream.puts
+            end
+          end
 
-        # Adds +:array+ as a valid migration key
-        def migration_keys
-          super + [:array]
-        end
+          def prepare_column_options(column)
+            spec = super
+            spec[:array] = "true" if column.array?
+            spec
+          end
 
-        private
+          def default_primary_key?(column)
+            schema_type(column) == :bigserial
+          end
 
-        def default_primary_key?(column)
-          schema_type(column) == :serial
-        end
+          def explicit_primary_key_default?(column)
+            column.type == :uuid || (column.type == :integer && !column.serial?)
+          end
 
-        def schema_type(column)
-          return super unless column.serial?
+          def schema_type(column)
+            return super unless column.serial?
 
-          if column.bigint?
-            :bigserial
-          else
-            :serial
+            if column.bigint?
+              :bigserial
+            else
+              :serial
+            end
           end
-        end
 
-        def schema_expression(column)
-          super unless column.serial?
-        end
+          def schema_expression(column)
+            super unless column.serial?
+          end
       end
     end
   end
diff --git a/activerecord/lib/active_record/connection_adapters/postgresql/schema_statements.rb b/activerecord/lib/active_record/connection_adapters/postgresql/schema_statements.rb
index f6860b9aba..bf5fbb30e1 100644
--- a/activerecord/lib/active_record/connection_adapters/postgresql/schema_statements.rb
+++ b/activerecord/lib/active_record/connection_adapters/postgresql/schema_statements.rb
@@ -1,24 +1,8 @@
-require 'active_support/core_ext/string/strip'
+# frozen_string_literal: true
 
 module ActiveRecord
   module ConnectionAdapters
     module PostgreSQL
-      class SchemaCreation < AbstractAdapter::SchemaCreation
-        private
-
-        def visit_ColumnDefinition(o)
-          o.sql_type = type_to_sql(o.type, o.limit, o.precision, o.scale, o.array)
-          super
-        end
-
-        def add_column_options!(sql, options)
-          if options[:collation]
-            sql << " COLLATE \"#{options[:collation]}\""
-          end
-          super
-        end
-      end
-
       module SchemaStatements
         # Drops the database specified on the +name+ attribute
         # and creates it again using the provided +options+.
@@ -36,26 +20,26 @@ module ActiveRecord
         #   create_database config[:database], config
         #   create_database 'foo_development', encoding: 'unicode'
         def create_database(name, options = {})
-          options = { encoding: 'utf8' }.merge!(options.symbolize_keys)
+          options = { encoding: "utf8" }.merge!(options.symbolize_keys)
 
           option_string = options.inject("") do |memo, (key, value)|
             memo += case key
-            when :owner
-              " OWNER = \"#{value}\""
-            when :template
-              " TEMPLATE = \"#{value}\""
-            when :encoding
-              " ENCODING = '#{value}'"
-            when :collation
-              " LC_COLLATE = '#{value}'"
-            when :ctype
-              " LC_CTYPE = '#{value}'"
-            when :tablespace
-              " TABLESPACE = \"#{value}\""
-            when :connection_limit
-              " CONNECTION LIMIT = #{value}"
+                    when :owner
+                      " OWNER = \"#{value}\""
+                    when :template
+                      " TEMPLATE = \"#{value}\""
+                    when :encoding
+                      " ENCODING = '#{value}'"
+                    when :collation
+                      " LC_COLLATE = '#{value}'"
+                    when :ctype
+                      " LC_CTYPE = '#{value}'"
+                    when :tablespace
+                      " TABLESPACE = \"#{value}\""
+                    when :connection_limit
+                      " CONNECTION LIMIT = #{value}"
             else
-              ""
+                      ""
             end
           end
 
@@ -70,123 +54,48 @@ module ActiveRecord
           execute "DROP DATABASE IF EXISTS #{quote_table_name(name)}"
         end
 
-        # Returns the list of all tables in the schema search path.
-        def tables(name = nil)
-          if name
-            ActiveSupport::Deprecation.warn(<<-MSG.squish)
-              Passing arguments to #tables is deprecated without replacement.
-            MSG
-          end
-
-          select_values("SELECT tablename FROM pg_tables WHERE schemaname = ANY(current_schemas(false))", 'SCHEMA')
-        end
-
-        def data_sources # :nodoc
-          select_values(<<-SQL, 'SCHEMA')
-            SELECT c.relname
-            FROM pg_class c
-            LEFT JOIN pg_namespace n ON n.oid = c.relnamespace
-            WHERE c.relkind IN ('r', 'v','m') -- (r)elation/table, (v)iew, (m)aterialized view
-            AND n.nspname = ANY (current_schemas(false))
-          SQL
-        end
-
-        # Returns true if table exists.
-        # If the schema is not specified as part of +name+ then it will only find tables within
-        # the current schema search path (regardless of permissions to access tables in other schemas)
-        def table_exists?(name)
-          ActiveSupport::Deprecation.warn(<<-MSG.squish)
-            #table_exists? currently checks both tables and views.
-            This behavior is deprecated and will be changed with Rails 5.1 to only check tables.
-            Use #data_source_exists? instead.
-          MSG
-
-          data_source_exists?(name)
-        end
-
-        def data_source_exists?(name)
-          name = Utils.extract_schema_qualified_name(name.to_s)
-          return false unless name.identifier
-
-          select_value(<<-SQL, 'SCHEMA').to_i > 0
-              SELECT COUNT(*)
-              FROM pg_class c
-              LEFT JOIN pg_namespace n ON n.oid = c.relnamespace
-              WHERE c.relkind IN ('r','v','m') -- (r)elation/table, (v)iew, (m)aterialized view
-              AND c.relname = '#{name.identifier}'
-              AND n.nspname = #{name.schema ? "'#{name.schema}'" : 'ANY (current_schemas(false))'}
-          SQL
-        end
-
-        def views # :nodoc:
-          select_values(<<-SQL, 'SCHEMA')
-            SELECT c.relname
-            FROM pg_class c
-            LEFT JOIN pg_namespace n ON n.oid = c.relnamespace
-            WHERE c.relkind IN ('v','m') -- (v)iew, (m)aterialized view
-            AND n.nspname = ANY (current_schemas(false))
-          SQL
-        end
-
-        def view_exists?(view_name) # :nodoc:
-          name = Utils.extract_schema_qualified_name(view_name.to_s)
-          return false unless name.identifier
-
-          select_values(<<-SQL, 'SCHEMA').any?
-            SELECT c.relname
-            FROM pg_class c
-            LEFT JOIN pg_namespace n ON n.oid = c.relnamespace
-            WHERE c.relkind IN ('v','m') -- (v)iew, (m)aterialized view
-            AND c.relname = '#{name.identifier}'
-            AND n.nspname = #{name.schema ? "'#{name.schema}'" : 'ANY (current_schemas(false))'}
-          SQL
-        end
-
         def drop_table(table_name, options = {}) # :nodoc:
           execute "DROP TABLE#{' IF EXISTS' if options[:if_exists]} #{quote_table_name(table_name)}#{' CASCADE' if options[:force] == :cascade}"
         end
 
         # Returns true if schema exists.
         def schema_exists?(name)
-          select_value("SELECT COUNT(*) FROM pg_namespace WHERE nspname = '#{name}'", 'SCHEMA').to_i > 0
+          query_value("SELECT COUNT(*) FROM pg_namespace WHERE nspname = #{quote(name)}", "SCHEMA").to_i > 0
         end
 
         # Verifies existence of an index with a given name.
-        def index_name_exists?(table_name, index_name, default)
-          table = Utils.extract_schema_qualified_name(table_name.to_s)
-          index = Utils.extract_schema_qualified_name(index_name.to_s)
+        def index_name_exists?(table_name, index_name)
+          table = quoted_scope(table_name)
+          index = quoted_scope(index_name)
 
-          select_value(<<-SQL, 'SCHEMA').to_i > 0
+          query_value(<<-SQL, "SCHEMA").to_i > 0
             SELECT COUNT(*)
             FROM pg_class t
             INNER JOIN pg_index d ON t.oid = d.indrelid
             INNER JOIN pg_class i ON d.indexrelid = i.oid
             LEFT JOIN pg_namespace n ON n.oid = i.relnamespace
             WHERE i.relkind = 'i'
-              AND i.relname = '#{index.identifier}'
-              AND t.relname = '#{table.identifier}'
-              AND n.nspname = #{index.schema ? "'#{index.schema}'" : 'ANY (current_schemas(false))'}
+              AND i.relname = #{index[:name]}
+              AND t.relname = #{table[:name]}
+              AND n.nspname = #{index[:schema]}
           SQL
         end
 
         # Returns an array of indexes for the given table.
-        def indexes(table_name, name = nil)
-          table = Utils.extract_schema_qualified_name(table_name.to_s)
+        def indexes(table_name) # :nodoc:
+          scope = quoted_scope(table_name)
 
-          result = query(<<-SQL, 'SCHEMA')
+          result = query(<<-SQL, "SCHEMA")
             SELECT distinct i.relname, d.indisunique, d.indkey, pg_get_indexdef(d.indexrelid), t.oid,
-                            pg_catalog.obj_description(i.oid, 'pg_class') AS comment,
-            (SELECT COUNT(*) FROM pg_opclass o
-               JOIN (SELECT unnest(string_to_array(d.indclass::text, ' '))::int oid) c
-                 ON o.oid = c.oid WHERE o.opcdefault = 'f')
+                            pg_catalog.obj_description(i.oid, 'pg_class') AS comment
             FROM pg_class t
             INNER JOIN pg_index d ON t.oid = d.indrelid
             INNER JOIN pg_class i ON d.indexrelid = i.oid
             LEFT JOIN pg_namespace n ON n.oid = i.relnamespace
             WHERE i.relkind = 'i'
               AND d.indisprimary = 'f'
-              AND t.relname = '#{table.identifier}'
-              AND n.nspname = #{table.schema ? "'#{table.schema}'" : 'ANY (current_schemas(false))'}
+              AND t.relname = #{scope[:name]}
+              AND n.nspname = #{scope[:schema]}
             ORDER BY i.relname
           SQL
 
@@ -197,11 +106,13 @@ module ActiveRecord
             inddef = row[3]
             oid = row[4]
             comment = row[5]
-            opclass = row[6]
 
             using, expressions, where = inddef.scan(/ USING (\w+?) \((.+?)\)(?: WHERE (.+))?\z/).flatten
 
-            if indkey.include?(0) || opclass > 0
+            orders = {}
+            opclasses = {}
+
+            if indkey.include?(0)
               columns = expressions
             else
               columns = Hash[query(<<-SQL.strip_heredoc, "SCHEMA")].values_at(*indkey).compact
@@ -211,76 +122,77 @@ module ActiveRecord
                 AND a.attnum IN (#{indkey.join(",")})
               SQL
 
-              # add info on sort order for columns (only desc order is explicitly specified, asc is the default)
-              orders = Hash[
-                expressions.scan(/(\w+) DESC/).flatten.map { |order_column| [order_column, :desc] }
-              ]
+              # add info on sort order (only desc order is explicitly specified, asc is the default)
+              # and non-default opclasses
+              expressions.scan(/(\w+)(?: (?!DESC)(\w+))?(?: (DESC))?/).each do |column, opclass, desc|
+                opclasses[column] = opclass.to_sym if opclass
+                orders[column] = :desc if desc
+              end
             end
 
-            IndexDefinition.new(table_name, index_name, unique, columns, [], orders, where, nil, using.to_sym, comment.presence)
-          end.compact
-        end
-
-        # Returns the list of all column definitions for a table.
-        def columns(table_name) # :nodoc:
-          table_name = table_name.to_s
-          column_definitions(table_name).map do |column_name, type, default, notnull, oid, fmod, collation, comment|
-            oid = oid.to_i
-            fmod = fmod.to_i
-            type_metadata = fetch_type_metadata(column_name, type, oid, fmod)
-            default_value = extract_value_from_default(default)
-            default_function = extract_default_function(default_value, default)
-            new_column(column_name, default_value, type_metadata, !notnull, table_name, default_function, collation, comment: comment.presence)
+            IndexDefinition.new(
+              table_name,
+              index_name,
+              unique,
+              columns,
+              orders: orders,
+              opclasses: opclasses,
+              where: where,
+              using: using.to_sym,
+              comment: comment.presence
+            )
           end
         end
 
-        def new_column(*args) # :nodoc:
-          PostgreSQLColumn.new(*args)
+        def table_options(table_name) # :nodoc:
+          if comment = table_comment(table_name)
+            { comment: comment }
+          end
         end
 
         # Returns a comment stored in database for given table
         def table_comment(table_name) # :nodoc:
-          name = Utils.extract_schema_qualified_name(table_name.to_s)
-          if name.identifier
-            select_value(<<-SQL.strip_heredoc, 'SCHEMA')
+          scope = quoted_scope(table_name, type: "BASE TABLE")
+          if scope[:name]
+            query_value(<<-SQL.strip_heredoc, "SCHEMA")
               SELECT pg_catalog.obj_description(c.oid, 'pg_class')
               FROM pg_catalog.pg_class c
                 LEFT JOIN pg_namespace n ON n.oid = c.relnamespace
-              WHERE c.relname = #{quote(name.identifier)}
-                AND c.relkind IN ('r') -- (r)elation/table
-                AND n.nspname = #{name.schema ? quote(name.schema) : 'ANY (current_schemas(false))'}
+              WHERE c.relname = #{scope[:name]}
+                AND c.relkind IN (#{scope[:type]})
+                AND n.nspname = #{scope[:schema]}
             SQL
           end
         end
 
         # Returns the current database name.
         def current_database
-          select_value('select current_database()', 'SCHEMA')
+          query_value("SELECT current_database()", "SCHEMA")
         end
 
         # Returns the current schema name.
         def current_schema
-          select_value('SELECT current_schema', 'SCHEMA')
+          query_value("SELECT current_schema", "SCHEMA")
         end
 
         # Returns the current database encoding format.
         def encoding
-          select_value("SELECT pg_encoding_to_char(encoding) FROM pg_database WHERE datname LIKE '#{current_database}'", 'SCHEMA')
+          query_value("SELECT pg_encoding_to_char(encoding) FROM pg_database WHERE datname = current_database()", "SCHEMA")
         end
 
         # Returns the current database collation.
         def collation
-          select_value("SELECT datcollate FROM pg_database WHERE datname LIKE '#{current_database}'", 'SCHEMA')
+          query_value("SELECT datcollate FROM pg_database WHERE datname = current_database()", "SCHEMA")
         end
 
         # Returns the current database ctype.
         def ctype
-          select_value("SELECT datctype FROM pg_database WHERE datname LIKE '#{current_database}'", 'SCHEMA')
+          query_value("SELECT datctype FROM pg_database WHERE datname = current_database()", "SCHEMA")
         end
 
         # Returns an array of schema names.
         def schema_names
-          select_values(<<-SQL, 'SCHEMA')
+          query_values(<<-SQL, "SCHEMA")
             SELECT nspname
               FROM pg_namespace
              WHERE nspname !~ '^pg_.*'
@@ -290,7 +202,7 @@ module ActiveRecord
         end
 
         # Creates a schema for the given schema name.
-        def create_schema schema_name
+        def create_schema(schema_name)
           execute "CREATE SCHEMA #{quote_schema_name(schema_name)}"
         end
 
@@ -301,42 +213,42 @@ module ActiveRecord
 
         # Sets the schema search path to a string of comma-separated schema names.
         # Names beginning with $ have to be quoted (e.g. $user => '$user').
-        # See: http://www.postgresql.org/docs/current/static/ddl-schemas.html
+        # See: https://www.postgresql.org/docs/current/static/ddl-schemas.html
         #
         # This should be not be called manually but set in database.yml.
         def schema_search_path=(schema_csv)
           if schema_csv
-            execute("SET search_path TO #{schema_csv}", 'SCHEMA')
+            execute("SET search_path TO #{schema_csv}", "SCHEMA")
             @schema_search_path = schema_csv
           end
         end
 
         # Returns the active schema search path.
         def schema_search_path
-          @schema_search_path ||= select_value('SHOW search_path', 'SCHEMA')
+          @schema_search_path ||= query_value("SHOW search_path", "SCHEMA")
         end
 
         # Returns the current client message level.
         def client_min_messages
-          select_value('SHOW client_min_messages', 'SCHEMA')
+          query_value("SHOW client_min_messages", "SCHEMA")
         end
 
         # Set the client message level.
         def client_min_messages=(level)
-          execute("SET client_min_messages TO '#{level}'", 'SCHEMA')
+          execute("SET client_min_messages TO '#{level}'", "SCHEMA")
         end
 
         # Returns the sequence name for a table's primary key or some other specified key.
-        def default_sequence_name(table_name, pk = nil) #:nodoc:
-          result = serial_sequence(table_name, pk || 'id')
+        def default_sequence_name(table_name, pk = "id") #:nodoc:
+          result = serial_sequence(table_name, pk)
           return nil unless result
           Utils.extract_schema_qualified_name(result).to_s
         rescue ActiveRecord::StatementInvalid
-          PostgreSQL::Name.new(nil, "#{table_name}_#{pk || 'id'}_seq").to_s
+          PostgreSQL::Name.new(nil, "#{table_name}_#{pk}_seq").to_s
         end
 
         def serial_sequence(table, column)
-          select_value("SELECT pg_get_serial_sequence('#{table}', '#{column}')", 'SCHEMA')
+          query_value("SELECT pg_get_serial_sequence(#{quote(table)}, #{quote(column)})", "SCHEMA")
         end
 
         # Sets the sequence of a table's primary key to the specified value.
@@ -347,7 +259,7 @@ module ActiveRecord
             if sequence
               quoted_sequence = quote_table_name(sequence)
 
-              select_value("SELECT setval('#{quoted_sequence}', #{value})", 'SCHEMA')
+              query_value("SELECT setval(#{quote(quoted_sequence)}, #{value})", "SCHEMA")
             else
               @logger.warn "#{table} has primary key #{pk} with no default sequence." if @logger
             end
@@ -356,7 +268,7 @@ module ActiveRecord
 
         # Resets the sequence of a table's primary key to the maximum value.
         def reset_pk_sequence!(table, pk = nil, sequence = nil) #:nodoc:
-          unless pk and sequence
+          unless pk && sequence
             default_pk, default_sequence = pk_and_sequence_for(table)
 
             pk ||= default_pk
@@ -369,10 +281,16 @@ module ActiveRecord
 
           if pk && sequence
             quoted_sequence = quote_table_name(sequence)
+            max_pk = query_value("SELECT MAX(#{quote_column_name pk}) FROM #{quote_table_name(table)}", "SCHEMA")
+            if max_pk.nil?
+              if postgresql_version >= 100000
+                minvalue = query_value("SELECT seqmin FROM pg_sequence WHERE seqrelid = #{quote(quoted_sequence)}::regclass", "SCHEMA")
+              else
+                minvalue = query_value("SELECT min_value FROM #{quoted_sequence}", "SCHEMA")
+              end
+            end
 
-            select_value(<<-end_sql, 'SCHEMA')
-              SELECT setval('#{quoted_sequence}', (SELECT COALESCE(MAX(#{quote_column_name pk})+(SELECT increment_by FROM #{quoted_sequence}), (SELECT min_value FROM #{quoted_sequence})) FROM #{quote_table_name(table)}), false)
-            end_sql
+            query_value("SELECT setval(#{quote(quoted_sequence)}, #{max_pk ? max_pk : minvalue}, #{max_pk ? true : false})", "SCHEMA")
           end
         end
 
@@ -380,7 +298,7 @@ module ActiveRecord
         def pk_and_sequence_for(table) #:nodoc:
           # First try looking for a sequence with a dependency on the
           # given table's primary key.
-          result = query(<<-end_sql, 'SCHEMA')[0]
+          result = query(<<-end_sql, "SCHEMA")[0]
             SELECT attr.attname, nsp.nspname, seq.relname
             FROM pg_class      seq,
                  pg_attribute  attr,
@@ -396,11 +314,11 @@ module ActiveRecord
               AND seq.relnamespace  = nsp.oid
               AND cons.contype      = 'p'
               AND dep.classid       = 'pg_class'::regclass
-              AND dep.refobjid      = '#{quote_table_name(table)}'::regclass
+              AND dep.refobjid      = #{quote(quote_table_name(table))}::regclass
           end_sql
 
-          if result.nil? or result.empty?
-            result = query(<<-end_sql, 'SCHEMA')[0]
+          if result.nil? || result.empty?
+            result = query(<<-end_sql, "SCHEMA")[0]
               SELECT attr.attname, nsp.nspname,
                 CASE
                   WHEN pg_get_expr(def.adbin, def.adrelid) !~* 'nextval' THEN NULL
@@ -414,7 +332,7 @@ module ActiveRecord
               JOIN pg_attrdef     def  ON (adrelid = attrelid AND adnum = attnum)
               JOIN pg_constraint  cons ON (conrelid = adrelid AND adnum = conkey[1])
               JOIN pg_namespace   nsp  ON (t.relnamespace = nsp.oid)
-              WHERE t.oid = '#{quote_table_name(table)}'::regclass
+              WHERE t.oid = #{quote(quote_table_name(table))}::regclass
                 AND cons.contype = 'p'
                 AND pg_get_expr(def.adbin, def.adrelid) ~* 'nextval|uuid_generate'
             end_sql
@@ -431,17 +349,18 @@ module ActiveRecord
         end
 
         def primary_keys(table_name) # :nodoc:
-          select_values(<<-SQL.strip_heredoc, 'SCHEMA')
-            WITH pk_constraint AS (
-              SELECT conrelid, unnest(conkey) AS connum FROM pg_constraint
-              WHERE contype = 'p'
-                AND conrelid = '#{quote_table_name(table_name)}'::regclass
-            ), cons AS (
-              SELECT conrelid, connum, row_number() OVER() AS rownum FROM pk_constraint
-            )
-            SELECT attr.attname FROM pg_attribute attr
-            INNER JOIN cons ON attr.attrelid = cons.conrelid AND attr.attnum = cons.connum
-            ORDER BY cons.rownum
+          query_values(<<-SQL.strip_heredoc, "SCHEMA")
+            SELECT a.attname
+              FROM (
+                     SELECT indrelid, indkey, generate_subscripts(indkey, 1) idx
+                       FROM pg_index
+                      WHERE indrelid = #{quote(quote_table_name(table_name))}::regclass
+                        AND indisprimary
+                   ) i
+              JOIN pg_attribute a
+                ON a.attrelid = i.indrelid
+               AND a.attnum = i.indkey[i.idx]
+             ORDER BY i.idx
           SQL
         end
 
@@ -455,14 +374,15 @@ module ActiveRecord
           clear_cache!
           execute "ALTER TABLE #{quote_table_name(table_name)} RENAME TO #{quote_table_name(new_name)}"
           pk, seq = pk_and_sequence_for(new_name)
-          if seq && seq.identifier == "#{table_name}_#{pk}_seq"
-            new_seq = "#{new_name}_#{pk}_seq"
+          if pk
             idx = "#{table_name}_pkey"
             new_idx = "#{new_name}_pkey"
-            execute "ALTER TABLE #{seq.quoted} RENAME TO #{quote_table_name(new_seq)}"
             execute "ALTER INDEX #{quote_table_name(idx)} RENAME TO #{quote_table_name(new_idx)}"
+            if seq && seq.identifier == "#{table_name}_#{pk}_seq"
+              new_seq = "#{new_name}_#{pk}_seq"
+              execute "ALTER TABLE #{seq.quoted} RENAME TO #{quote_table_name(new_seq)}"
+            end
           end
-
           rename_table_indexes(table_name, new_name)
         end
 
@@ -474,50 +394,23 @@ module ActiveRecord
 
         def change_column(table_name, column_name, type, options = {}) #:nodoc:
           clear_cache!
-          quoted_table_name = quote_table_name(table_name)
-          quoted_column_name = quote_column_name(column_name)
-          sql_type = type_to_sql(type, options[:limit], options[:precision], options[:scale], options[:array])
-          sql = "ALTER TABLE #{quoted_table_name} ALTER COLUMN #{quoted_column_name} TYPE #{sql_type}"
-          if options[:collation]
-            sql << " COLLATE \"#{options[:collation]}\""
-          end
-          if options[:using]
-            sql << " USING #{options[:using]}"
-          elsif options[:cast_as]
-            cast_as_type = type_to_sql(options[:cast_as], options[:limit], options[:precision], options[:scale], options[:array])
-            sql << " USING CAST(#{quoted_column_name} AS #{cast_as_type})"
-          end
-          execute sql
-
-          change_column_default(table_name, column_name, options[:default]) if options_include_default?(options)
-          change_column_null(table_name, column_name, options[:null], options[:default]) if options.key?(:null)
-          change_column_comment(table_name, column_name, options[:comment]) if options.key?(:comment)
+          sqls, procs = change_column_for_alter(table_name, column_name, type, options)
+          execute "ALTER TABLE #{quote_table_name(table_name)} #{sqls.join(", ")}"
+          procs.each(&:call)
         end
 
         # Changes the default value of a table column.
         def change_column_default(table_name, column_name, default_or_changes) # :nodoc:
-          clear_cache!
-          column = column_for(table_name, column_name)
-          return unless column
-
-          default = extract_new_default_value(default_or_changes)
-          alter_column_query = "ALTER TABLE #{quote_table_name(table_name)} ALTER COLUMN #{quote_column_name(column_name)} %s"
-          if default.nil?
-            # <tt>DEFAULT NULL</tt> results in the same behavior as <tt>DROP DEFAULT</tt>. However, PostgreSQL will
-            # cast the default to the columns type, which leaves us with a default like "default NULL::character varying".
-            execute alter_column_query % "DROP DEFAULT"
-          else
-            execute alter_column_query % "SET DEFAULT #{quote_default_expression(default, column)}"
-          end
+          execute "ALTER TABLE #{quote_table_name(table_name)} #{change_column_default_for_alter(table_name, column_name, default_or_changes)}"
         end
 
         def change_column_null(table_name, column_name, null, default = nil) #:nodoc:
           clear_cache!
           unless null || default.nil?
             column = column_for(table_name, column_name)
-            execute("UPDATE #{quote_table_name(table_name)} SET #{quote_column_name(column_name)}=#{quote_default_expression(default, column)} WHERE #{quote_column_name(column_name)} IS NULL") if column
+            execute "UPDATE #{quote_table_name(table_name)} SET #{quote_column_name(column_name)}=#{quote_default_expression(default, column)} WHERE #{quote_column_name(column_name)} IS NULL" if column
           end
-          execute("ALTER TABLE #{quote_table_name(table_name)} ALTER #{quote_column_name(column_name)} #{null ? 'DROP' : 'SET'} NOT NULL")
+          execute "ALTER TABLE #{quote_table_name(table_name)} #{change_column_null_for_alter(table_name, column_name, null, default)}"
         end
 
         # Adds comment for given table column or drops it if +comment+ is a +nil+
@@ -540,8 +433,8 @@ module ActiveRecord
         end
 
         def add_index(table_name, column_name, options = {}) #:nodoc:
-          index_name, index_type, index_columns, index_options, index_algorithm, index_using, comment = add_index_options(table_name, column_name, options)
-          execute("CREATE #{index_type} INDEX #{index_algorithm} #{quote_column_name(index_name)} ON #{quote_table_name(table_name)} #{index_using} (#{index_columns})#{index_options}").tap do
+          index_name, index_type, index_columns_and_opclasses, index_options, index_algorithm, index_using, comment = add_index_options(table_name, column_name, options)
+          execute("CREATE #{index_type} INDEX #{index_algorithm} #{quote_column_name(index_name)} ON #{quote_table_name(table_name)} #{index_using} (#{index_columns_and_opclasses})#{index_options}").tap do
             execute "COMMENT ON INDEX #{quote_column_name(index_name)} IS #{quote(comment)}" if comment
           end
         end
@@ -579,8 +472,9 @@ module ActiveRecord
         end
 
         def foreign_keys(table_name)
-          fk_info = select_all <<-SQL.strip_heredoc
-            SELECT t2.oid::regclass::text AS to_table, a1.attname AS column, a2.attname AS primary_key, c.conname AS name, c.confupdtype AS on_update, c.confdeltype AS on_delete
+          scope = quoted_scope(table_name)
+          fk_info = exec_query(<<-SQL.strip_heredoc, "SCHEMA")
+            SELECT t2.oid::regclass::text AS to_table, a1.attname AS column, a2.attname AS primary_key, c.conname AS name, c.confupdtype AS on_update, c.confdeltype AS on_delete, c.convalidated AS valid
             FROM pg_constraint c
             JOIN pg_class t1 ON c.conrelid = t1.oid
             JOIN pg_class t2 ON c.confrelid = t2.oid
@@ -588,94 +482,261 @@ module ActiveRecord
             JOIN pg_attribute a2 ON a2.attnum = c.confkey[1] AND a2.attrelid = t2.oid
             JOIN pg_namespace t3 ON c.connamespace = t3.oid
             WHERE c.contype = 'f'
-              AND t1.relname = #{quote(table_name)}
-              AND t3.nspname = ANY (current_schemas(false))
+              AND t1.relname = #{scope[:name]}
+              AND t3.nspname = #{scope[:schema]}
             ORDER BY c.conname
           SQL
 
           fk_info.map do |row|
             options = {
-              column: row['column'],
-              name: row['name'],
-              primary_key: row['primary_key']
+              column: row["column"],
+              name: row["name"],
+              primary_key: row["primary_key"]
             }
 
-            options[:on_delete] = extract_foreign_key_action(row['on_delete'])
-            options[:on_update] = extract_foreign_key_action(row['on_update'])
+            options[:on_delete] = extract_foreign_key_action(row["on_delete"])
+            options[:on_update] = extract_foreign_key_action(row["on_update"])
+            options[:validate] = row["valid"]
 
-            ForeignKeyDefinition.new(table_name, row['to_table'], options)
+            ForeignKeyDefinition.new(table_name, row["to_table"], options)
           end
         end
 
-        def extract_foreign_key_action(specifier) # :nodoc:
-          case specifier
-          when 'c'; :cascade
-          when 'n'; :nullify
-          when 'r'; :restrict
-          end
-        end
-
-        def index_name_length
-          63
-        end
-
         # Maps logical Rails types to PostgreSQL-specific data types.
-        def type_to_sql(type, limit = nil, precision = nil, scale = nil, array = nil)
-          sql = case type.to_s
-          when 'binary'
-            # PostgreSQL doesn't support limits on binary (bytea) columns.
-            # The hard limit is 1GB, because of a 32-bit size field, and TOAST.
-            case limit
-            when nil, 0..0x3fffffff; super(type)
-            else raise(ActiveRecordError, "No binary type has byte size #{limit}.")
-            end
-          when 'text'
-            # PostgreSQL doesn't support limits on text columns.
-            # The hard limit is 1GB, according to section 8.3 in the manual.
-            case limit
-            when nil, 0..0x3fffffff; super(type)
-            else raise(ActiveRecordError, "The limit on text can be at most 1GB - 1byte.")
-            end
-          when 'integer'
-            case limit
-            when 1, 2; 'smallint'
-            when nil, 3, 4; 'integer'
-            when 5..8; 'bigint'
-            else raise(ActiveRecordError, "No integer type has byte size #{limit}. Use a numeric with scale 0 instead.")
+        def type_to_sql(type, limit: nil, precision: nil, scale: nil, array: nil, **) # :nodoc:
+          sql = \
+            case type.to_s
+            when "binary"
+              # PostgreSQL doesn't support limits on binary (bytea) columns.
+              # The hard limit is 1GB, because of a 32-bit size field, and TOAST.
+              case limit
+              when nil, 0..0x3fffffff; super(type)
+              else raise(ActiveRecordError, "No binary type has byte size #{limit}.")
+              end
+            when "text"
+              # PostgreSQL doesn't support limits on text columns.
+              # The hard limit is 1GB, according to section 8.3 in the manual.
+              case limit
+              when nil, 0..0x3fffffff; super(type)
+              else raise(ActiveRecordError, "The limit on text can be at most 1GB - 1byte.")
+              end
+            when "integer"
+              case limit
+              when 1, 2; "smallint"
+              when nil, 3, 4; "integer"
+              when 5..8; "bigint"
+              else raise(ActiveRecordError, "No integer type has byte size #{limit}. Use a numeric with scale 0 instead.")
+              end
+            else
+              super
             end
-          else
-            super(type, limit, precision, scale)
-          end
 
-          sql << '[]' if array && type != :primary_key
+          sql = "#{sql}[]" if array && type != :primary_key
           sql
         end
 
         # PostgreSQL requires the ORDER BY columns in the select list for distinct queries, and
         # requires that the ORDER BY include the distinct column.
         def columns_for_distinct(columns, orders) #:nodoc:
-          order_columns = orders.reject(&:blank?).map{ |s|
+          order_columns = orders.reject(&:blank?).map { |s|
               # Convert Arel node to string
               s = s.to_sql unless s.is_a?(String)
               # Remove any ASC/DESC modifiers
-              s.gsub(/\s+(?:ASC|DESC)\b/i, '')
-               .gsub(/\s+NULLS\s+(?:FIRST|LAST)\b/i, '')
+              s.gsub(/\s+(?:ASC|DESC)\b/i, "")
+               .gsub(/\s+NULLS\s+(?:FIRST|LAST)\b/i, "")
             }.reject(&:blank?).map.with_index { |column, i| "#{column} AS alias_#{i}" }
 
-          [super, *order_columns].join(', ')
+          [super, *order_columns].join(", ")
         end
 
-        def fetch_type_metadata(column_name, sql_type, oid, fmod)
-          cast_type = get_oid_type(oid, fmod, column_name, sql_type)
-          simple_type = SqlTypeMetadata.new(
-            sql_type: sql_type,
-            type: cast_type.type,
-            limit: cast_type.limit,
-            precision: cast_type.precision,
-            scale: cast_type.scale,
-          )
-          PostgreSQLTypeMetadata.new(simple_type, oid: oid, fmod: fmod)
+        def update_table_definition(table_name, base) # :nodoc:
+          PostgreSQL::Table.new(table_name, base)
         end
+
+        def create_schema_dumper(options) # :nodoc:
+          PostgreSQL::SchemaDumper.create(self, options)
+        end
+
+        # Validates the given constraint.
+        #
+        # Validates the constraint named +constraint_name+ on +accounts+.
+        #
+        #   validate_constraint :accounts, :constraint_name
+        def validate_constraint(table_name, constraint_name)
+          return unless supports_validate_constraints?
+
+          at = create_alter_table table_name
+          at.validate_constraint constraint_name
+
+          execute schema_creation.accept(at)
+        end
+
+        # Validates the given foreign key.
+        #
+        # Validates the foreign key on +accounts.branch_id+.
+        #
+        #   validate_foreign_key :accounts, :branches
+        #
+        # Validates the foreign key on +accounts.owner_id+.
+        #
+        #   validate_foreign_key :accounts, column: :owner_id
+        #
+        # Validates the foreign key named +special_fk_name+ on the +accounts+ table.
+        #
+        #   validate_foreign_key :accounts, name: :special_fk_name
+        #
+        # The +options+ hash accepts the same keys as SchemaStatements#add_foreign_key.
+        def validate_foreign_key(from_table, options_or_to_table = {})
+          return unless supports_validate_constraints?
+
+          fk_name_to_validate = foreign_key_for!(from_table, options_or_to_table).name
+
+          validate_constraint from_table, fk_name_to_validate
+        end
+
+        private
+          def schema_creation
+            PostgreSQL::SchemaCreation.new(self)
+          end
+
+          def create_table_definition(*args)
+            PostgreSQL::TableDefinition.new(*args)
+          end
+
+          def create_alter_table(name)
+            PostgreSQL::AlterTable.new create_table_definition(name)
+          end
+
+          def new_column_from_field(table_name, field)
+            column_name, type, default, notnull, oid, fmod, collation, comment = field
+            type_metadata = fetch_type_metadata(column_name, type, oid.to_i, fmod.to_i)
+            default_value = extract_value_from_default(default)
+            default_function = extract_default_function(default_value, default)
+
+            PostgreSQLColumn.new(
+              column_name,
+              default_value,
+              type_metadata,
+              !notnull,
+              table_name,
+              default_function,
+              collation,
+              comment: comment.presence,
+              max_identifier_length: max_identifier_length
+            )
+          end
+
+          def fetch_type_metadata(column_name, sql_type, oid, fmod)
+            cast_type = get_oid_type(oid, fmod, column_name, sql_type)
+            simple_type = SqlTypeMetadata.new(
+              sql_type: sql_type,
+              type: cast_type.type,
+              limit: cast_type.limit,
+              precision: cast_type.precision,
+              scale: cast_type.scale,
+            )
+            PostgreSQLTypeMetadata.new(simple_type, oid: oid, fmod: fmod)
+          end
+
+          def extract_foreign_key_action(specifier)
+            case specifier
+            when "c"; :cascade
+            when "n"; :nullify
+            when "r"; :restrict
+            end
+          end
+
+          def change_column_sql(table_name, column_name, type, options = {})
+            quoted_column_name = quote_column_name(column_name)
+            sql_type = type_to_sql(type, options)
+            sql = "ALTER COLUMN #{quoted_column_name} TYPE #{sql_type}".dup
+            if options[:collation]
+              sql << " COLLATE \"#{options[:collation]}\""
+            end
+            if options[:using]
+              sql << " USING #{options[:using]}"
+            elsif options[:cast_as]
+              cast_as_type = type_to_sql(options[:cast_as], options)
+              sql << " USING CAST(#{quoted_column_name} AS #{cast_as_type})"
+            end
+
+            sql
+          end
+
+          def change_column_for_alter(table_name, column_name, type, options = {})
+            sqls = [change_column_sql(table_name, column_name, type, options)]
+            procs = []
+            sqls << change_column_default_for_alter(table_name, column_name, options[:default]) if options.key?(:default)
+            sqls << change_column_null_for_alter(table_name, column_name, options[:null], options[:default]) if options.key?(:null)
+            procs << Proc.new { change_column_comment(table_name, column_name, options[:comment]) } if options.key?(:comment)
+
+            [sqls, procs]
+          end
+
+
+          # Changes the default value of a table column.
+          def change_column_default_for_alter(table_name, column_name, default_or_changes) # :nodoc:
+            column = column_for(table_name, column_name)
+            return unless column
+
+            default = extract_new_default_value(default_or_changes)
+            alter_column_query = "ALTER COLUMN #{quote_column_name(column_name)} %s"
+            if default.nil?
+              # <tt>DEFAULT NULL</tt> results in the same behavior as <tt>DROP DEFAULT</tt>. However, PostgreSQL will
+              # cast the default to the columns type, which leaves us with a default like "default NULL::character varying".
+              alter_column_query % "DROP DEFAULT"
+            else
+              alter_column_query % "SET DEFAULT #{quote_default_expression(default, column)}"
+            end
+          end
+
+          def change_column_null_for_alter(table_name, column_name, null, default = nil) #:nodoc:
+            "ALTER #{quote_column_name(column_name)} #{null ? 'DROP' : 'SET'} NOT NULL"
+          end
+
+          def add_index_opclass(quoted_columns, **options)
+            opclasses = options_for_index_columns(options[:opclass])
+            quoted_columns.each do |name, column|
+              column << " #{opclasses[name]}" if opclasses[name].present?
+            end
+          end
+
+          def add_options_for_index_columns(quoted_columns, **options)
+            quoted_columns = add_index_opclass(quoted_columns, options)
+            super
+          end
+
+          def data_source_sql(name = nil, type: nil)
+            scope = quoted_scope(name, type: type)
+            scope[:type] ||= "'r','v','m'" # (r)elation/table, (v)iew, (m)aterialized view
+
+            sql = "SELECT c.relname FROM pg_class c LEFT JOIN pg_namespace n ON n.oid = c.relnamespace".dup
+            sql << " WHERE n.nspname = #{scope[:schema]}"
+            sql << " AND c.relname = #{scope[:name]}" if scope[:name]
+            sql << " AND c.relkind IN (#{scope[:type]})"
+            sql
+          end
+
+          def quoted_scope(name = nil, type: nil)
+            schema, name = extract_schema_qualified_name(name)
+            type = \
+              case type
+              when "BASE TABLE"
+                "'r'"
+              when "VIEW"
+                "'v','m'"
+              end
+            scope = {}
+            scope[:schema] = schema ? quote(schema) : "ANY (current_schemas(false))"
+            scope[:name] = quote(name) if name
+            scope[:type] = type if type
+            scope
+          end
+
+          def extract_schema_qualified_name(string)
+            name = Utils.extract_schema_qualified_name(string.to_s)
+            [name.schema, name.identifier]
+          end
       end
     end
   end
diff --git a/activerecord/lib/active_record/connection_adapters/postgresql/type_metadata.rb b/activerecord/lib/active_record/connection_adapters/postgresql/type_metadata.rb
index b2c49989a4..b252a76caa 100644
--- a/activerecord/lib/active_record/connection_adapters/postgresql/type_metadata.rb
+++ b/activerecord/lib/active_record/connection_adapters/postgresql/type_metadata.rb
@@ -1,6 +1,10 @@
+# frozen_string_literal: true
+
 module ActiveRecord
   module ConnectionAdapters
     class PostgreSQLTypeMetadata < DelegateClass(SqlTypeMetadata)
+      undef to_yaml if method_defined?(:to_yaml)
+
       attr_reader :oid, :fmod, :array
 
       def initialize(type_metadata, oid: nil, fmod: nil)
@@ -8,7 +12,7 @@ module ActiveRecord
         @type_metadata = type_metadata
         @oid = oid
         @fmod = fmod
-        @array = /\[\]$/ === type_metadata.sql_type
+        @array = /\[\]$/.match?(type_metadata.sql_type)
       end
 
       def sql_type
@@ -27,9 +31,9 @@ module ActiveRecord
 
       protected
 
-      def attributes_for_hash
-        [self.class, @type_metadata, oid, fmod]
-      end
+        def attributes_for_hash
+          [self.class, @type_metadata, oid, fmod]
+        end
     end
   end
 end
diff --git a/activerecord/lib/active_record/connection_adapters/postgresql/utils.rb b/activerecord/lib/active_record/connection_adapters/postgresql/utils.rb
index 9a0b80d7d3..bfd300723d 100644
--- a/activerecord/lib/active_record/connection_adapters/postgresql/utils.rb
+++ b/activerecord/lib/active_record/connection_adapters/postgresql/utils.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActiveRecord
   module ConnectionAdapters
     module PostgreSQL
@@ -19,9 +21,9 @@ module ActiveRecord
 
         def quoted
           if schema
-            PGconn.quote_ident(schema) << SEPARATOR << PGconn.quote_ident(identifier)
+            PG::Connection.quote_ident(schema) << SEPARATOR << PG::Connection.quote_ident(identifier)
           else
-            PGconn.quote_ident(identifier)
+            PG::Connection.quote_ident(identifier)
           end
         end
 
@@ -35,6 +37,12 @@ module ActiveRecord
         end
 
         protected
+
+          def parts
+            @parts ||= [@schema, @identifier].compact
+          end
+
+        private
           def unquote(part)
             if part && part.start_with?('"')
               part[1..-2]
@@ -42,10 +50,6 @@ module ActiveRecord
               part
             end
           end
-
-          def parts
-            @parts ||= [@schema, @identifier].compact
-          end
       end
 
       module Utils # :nodoc:
@@ -53,7 +57,7 @@ module ActiveRecord
 
         # Returns an instance of <tt>ActiveRecord::ConnectionAdapters::PostgreSQL::Name</tt>
         # extracted from +string+.
-        # +schema+ is nil if not specified in +string+.
+        # +schema+ is +nil+ if not specified in +string+.
         # +schema+ and +identifier+ exclude surrounding quotes (regardless of whether provided in +string+)
         # +string+ supports the range of schema/table references understood by PostgreSQL, for example:
         #
diff --git a/activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb b/activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb
index ddfc560747..23fc69d649 100644
--- a/activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb
+++ b/activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb
@@ -1,20 +1,23 @@
+# frozen_string_literal: true
+
 # Make sure we're using pg high enough for type casts and Ruby 2.2+ compatibility
-gem 'pg', '~> 0.18'
-require 'pg'
+gem "pg", "~> 0.18"
+require "pg"
 
 require "active_record/connection_adapters/abstract_adapter"
+require "active_record/connection_adapters/statement_pool"
 require "active_record/connection_adapters/postgresql/column"
 require "active_record/connection_adapters/postgresql/database_statements"
 require "active_record/connection_adapters/postgresql/explain_pretty_printer"
 require "active_record/connection_adapters/postgresql/oid"
 require "active_record/connection_adapters/postgresql/quoting"
 require "active_record/connection_adapters/postgresql/referential_integrity"
+require "active_record/connection_adapters/postgresql/schema_creation"
 require "active_record/connection_adapters/postgresql/schema_definitions"
 require "active_record/connection_adapters/postgresql/schema_dumper"
 require "active_record/connection_adapters/postgresql/schema_statements"
 require "active_record/connection_adapters/postgresql/type_metadata"
 require "active_record/connection_adapters/postgresql/utils"
-require "active_record/connection_adapters/statement_pool"
 
 module ActiveRecord
   module ConnectionHandling # :nodoc:
@@ -28,11 +31,11 @@ module ActiveRecord
       conn_params[:user] = conn_params.delete(:username) if conn_params[:username]
       conn_params[:dbname] = conn_params.delete(:database) if conn_params[:database]
 
-      # Forward only valid config params to PGconn.connect.
-      valid_conn_param_keys = PGconn.conndefaults_hash.keys + [:requiressl]
+      # Forward only valid config params to PG::Connection.connect.
+      valid_conn_param_keys = PG::Connection.conndefaults_hash.keys + [:requiressl]
       conn_params.slice!(*valid_conn_param_keys)
 
-      # The postgres drivers don't allow the creation of an unconnected PGconn object,
+      # The postgres drivers don't allow the creation of an unconnected PG::Connection object,
       # so just pass a nil connection object for the time being.
       ConnectionAdapters::PostgreSQLAdapter.new(nil, logger, conn_params, config)
     end
@@ -61,19 +64,19 @@ module ActiveRecord
     #   defaults to true.
     #
     # Any further options are used as connection parameters to libpq. See
-    # http://www.postgresql.org/docs/current/static/libpq-connect.html for the
+    # https://www.postgresql.org/docs/current/static/libpq-connect.html for the
     # list of parameters.
     #
     # In addition, default connection parameters of libpq can be set per environment variables.
-    # See http://www.postgresql.org/docs/current/static/libpq-envars.html .
+    # See https://www.postgresql.org/docs/current/static/libpq-envars.html .
     class PostgreSQLAdapter < AbstractAdapter
-      ADAPTER_NAME = 'PostgreSQL'.freeze
+      ADAPTER_NAME = "PostgreSQL".freeze
 
       NATIVE_DATABASE_TYPES = {
-        primary_key: "serial primary key",
+        primary_key: "bigserial primary key",
         string:      { name: "character varying" },
         text:        { name: "text" },
-        integer:     { name: "integer" },
+        integer:     { name: "integer", limit: 4 },
         float:       { name: "float" },
         decimal:     { name: "decimal" },
         datetime:    { name: "timestamp" },
@@ -108,6 +111,8 @@ module ActiveRecord
         bit:         { name: "bit" },
         bit_varying: { name: "bit varying" },
         money:       { name: "money" },
+        interval:    { name: "interval" },
+        oid:         { name: "oid" },
       }
 
       OID = PostgreSQL::OID #:nodoc:
@@ -116,21 +121,6 @@ module ActiveRecord
       include PostgreSQL::ReferentialIntegrity
       include PostgreSQL::SchemaStatements
       include PostgreSQL::DatabaseStatements
-      include PostgreSQL::ColumnDumper
-
-      def schema_creation # :nodoc:
-        PostgreSQL::SchemaCreation.new self
-      end
-
-      def arel_visitor # :nodoc:
-        Arel::Visitors::PostgreSQL.new(self)
-      end
-
-      # Returns true, since this connection adapter supports prepared statement
-      # caching.
-      def supports_statement_cache?
-        true
-      end
 
       def supports_index_sort_order?
         true
@@ -152,6 +142,10 @@ module ActiveRecord
         true
       end
 
+      def supports_validate_constraints?
+        true
+      end
+
       def supports_views?
         true
       end
@@ -173,10 +167,10 @@ module ActiveRecord
       end
 
       def index_algorithms
-        { concurrently: 'CONCURRENTLY' }
+        { concurrently: "CONCURRENTLY" }
       end
 
-      class StatementPool < ConnectionAdapters::StatementPool
+      class StatementPool < ConnectionAdapters::StatementPool # :nodoc:
         def initialize(connection, max)
           super(max)
           @connection = connection
@@ -192,14 +186,14 @@ module ActiveRecord
         end
 
         private
-
           def dealloc(key)
             @connection.query "DEALLOCATE #{key}" if connection_active?
+          rescue PG::Error
           end
 
           def connection_active?
-            @connection.status == PGconn::CONNECTION_OK
-          rescue PGError
+            @connection.status == PG::CONNECTION_OK
+          rescue PG::Error
             false
           end
       end
@@ -212,7 +206,7 @@ module ActiveRecord
 
         # @local_tz is initialized as nil to avoid warnings when connect tries to use it
         @local_tz = nil
-        @table_alias_length = nil
+        @max_identifier_length = nil
 
         connect
         add_pg_encoders
@@ -226,14 +220,16 @@ module ActiveRecord
         add_pg_decoders
 
         @type_map = Type::HashLookupTypeMap.new
-        initialize_type_map(type_map)
-        @local_tz = execute('SHOW TIME ZONE', 'SCHEMA').first["TimeZone"]
+        initialize_type_map
+        @local_tz = execute("SHOW TIME ZONE", "SCHEMA").first["TimeZone"]
         @use_insert_returning = @config.key?(:insert_returning) ? self.class.type_cast_config_to_boolean(@config[:insert_returning]) : true
       end
 
       # Clears the prepared statements cache.
       def clear_cache!
-        @statements.clear
+        @lock.synchronize do
+          @statements.clear
+        end
       end
 
       def truncate(table_name, name = nil)
@@ -242,52 +238,55 @@ module ActiveRecord
 
       # Is this connection alive and ready for queries?
       def active?
-        @connection.query 'SELECT 1'
+        @lock.synchronize do
+          @connection.query "SELECT 1"
+        end
         true
-      rescue PGError
+      rescue PG::Error
         false
       end
 
       # Close then reopen the connection.
       def reconnect!
-        super
-        @connection.reset
-        configure_connection
+        @lock.synchronize do
+          super
+          @connection.reset
+          configure_connection
+        end
       end
 
       def reset!
-        clear_cache!
-        reset_transaction
-        unless @connection.transaction_status == ::PG::PQTRANS_IDLE
-          @connection.query 'ROLLBACK'
+        @lock.synchronize do
+          clear_cache!
+          reset_transaction
+          unless @connection.transaction_status == ::PG::PQTRANS_IDLE
+            @connection.query "ROLLBACK"
+          end
+          @connection.query "DISCARD ALL"
+          configure_connection
         end
-        @connection.query 'DISCARD ALL'
-        configure_connection
       end
 
       # Disconnects from the database if already connected. Otherwise, this
       # method does nothing.
       def disconnect!
-        super
-        @connection.close rescue nil
-      end
-
-      def native_database_types #:nodoc:
-        NATIVE_DATABASE_TYPES
+        @lock.synchronize do
+          super
+          @connection.close rescue nil
+        end
       end
 
-      # Returns true, since this connection adapter supports migrations.
-      def supports_migrations?
-        true
+      def discard! # :nodoc:
+        @connection.socket_io.reopen(IO::NULL)
+        @connection = nil
       end
 
-      # Does PostgreSQL support finding primary key on non-Active Record tables?
-      def supports_primary_key? #:nodoc:
-        true
+      def native_database_types #:nodoc:
+        NATIVE_DATABASE_TYPES
       end
 
       def set_standard_conforming_strings
-        execute('SET standard_conforming_strings = on', 'SCHEMA')
+        execute("SET standard_conforming_strings = on", "SCHEMA")
       end
 
       def supports_ddl_transactions?
@@ -306,8 +305,8 @@ module ActiveRecord
         true
       end
 
-      # Range datatypes weren't introduced until PostgreSQL 9.2
       def supports_ranges?
+        # Range datatypes weren't introduced until PostgreSQL 9.2
         postgresql_version >= 90200
       end
 
@@ -315,18 +314,22 @@ module ActiveRecord
         postgresql_version >= 90300
       end
 
+      def supports_pgcrypto_uuid?
+        postgresql_version >= 90400
+      end
+
       def get_advisory_lock(lock_id) # :nodoc:
         unless lock_id.is_a?(Integer) && lock_id.bit_length <= 63
-          raise(ArgumentError, "Postgres requires advisory lock ids to be a signed 64 bit integer")
+          raise(ArgumentError, "PostgreSQL requires advisory lock ids to be a signed 64 bit integer")
         end
-        select_value("SELECT pg_try_advisory_lock(#{lock_id});")
+        query_value("SELECT pg_try_advisory_lock(#{lock_id})")
       end
 
       def release_advisory_lock(lock_id) # :nodoc:
         unless lock_id.is_a?(Integer) && lock_id.bit_length <= 63
-          raise(ArgumentError, "Postgres requires advisory lock ids to be a signed 64 bit integer")
+          raise(ArgumentError, "PostgreSQL requires advisory lock ids to be a signed 64 bit integer")
         end
-        select_value("SELECT pg_advisory_unlock(#{lock_id})")
+        query_value("SELECT pg_advisory_unlock(#{lock_id})")
       end
 
       def enable_extension(name)
@@ -342,49 +345,31 @@ module ActiveRecord
       end
 
       def extension_enabled?(name)
-        if supports_extensions?
-          res = exec_query "SELECT EXISTS(SELECT * FROM pg_available_extensions WHERE name = '#{name}' AND installed_version IS NOT NULL) as enabled",
-            'SCHEMA'
-          res.cast_values.first
-        end
+        res = exec_query("SELECT EXISTS(SELECT * FROM pg_available_extensions WHERE name = '#{name}' AND installed_version IS NOT NULL) as enabled", "SCHEMA")
+        res.cast_values.first
       end
 
       def extensions
-        if supports_extensions?
-          exec_query("SELECT extname from pg_extension", "SCHEMA").cast_values
-        else
-          super
-        end
+        exec_query("SELECT extname FROM pg_extension", "SCHEMA").cast_values
       end
 
       # Returns the configured supported identifier length supported by PostgreSQL
-      def table_alias_length
-        @table_alias_length ||= query('SHOW max_identifier_length', 'SCHEMA')[0][0].to_i
+      def max_identifier_length
+        @max_identifier_length ||= query_value("SHOW max_identifier_length", "SCHEMA").to_i
       end
+      alias table_alias_length max_identifier_length
+      alias index_name_length max_identifier_length
 
       # Set the authorized user for this session
       def session_auth=(user)
         clear_cache!
-        exec_query "SET SESSION AUTHORIZATION #{user}"
+        execute("SET SESSION AUTHORIZATION #{user}")
       end
 
       def use_insert_returning?
         @use_insert_returning
       end
 
-      def valid_type?(type)
-        !native_database_types[type].nil?
-      end
-
-      def update_table_definition(table_name, base) #:nodoc:
-        PostgreSQL::Table.new(table_name, base)
-      end
-
-      def lookup_cast_type(sql_type) # :nodoc:
-        oid = execute("SELECT #{quote(sql_type)}::regtype::oid", "SCHEMA").first['oid'].to_i
-        super(oid)
-      end
-
       def column_name_for_operation(operation, node) # :nodoc:
         OPERATION_ALIASES.fetch(operation) { operation.downcase }
       end
@@ -400,92 +385,110 @@ module ActiveRecord
         @connection.server_version
       end
 
-      protected
+      def default_index_type?(index) # :nodoc:
+        index.using == :btree || super
+      end
 
-        # See http://www.postgresql.org/docs/current/static/errcodes-appendix.html
+      private
+        # See https://www.postgresql.org/docs/current/static/errcodes-appendix.html
         VALUE_LIMIT_VIOLATION = "22001"
+        NUMERIC_VALUE_OUT_OF_RANGE = "22003"
+        NOT_NULL_VIOLATION    = "23502"
         FOREIGN_KEY_VIOLATION = "23503"
         UNIQUE_VIOLATION      = "23505"
         SERIALIZATION_FAILURE = "40001"
+        DEADLOCK_DETECTED     = "40P01"
+        LOCK_NOT_AVAILABLE    = "55P03"
+        QUERY_CANCELED        = "57014"
 
         def translate_exception(exception, message)
           return exception unless exception.respond_to?(:result)
 
-          case exception.result.try(:error_field, PGresult::PG_DIAG_SQLSTATE)
+          case exception.result.try(:error_field, PG::PG_DIAG_SQLSTATE)
           when UNIQUE_VIOLATION
             RecordNotUnique.new(message)
           when FOREIGN_KEY_VIOLATION
             InvalidForeignKey.new(message)
           when VALUE_LIMIT_VIOLATION
             ValueTooLong.new(message)
+          when NUMERIC_VALUE_OUT_OF_RANGE
+            RangeError.new(message)
+          when NOT_NULL_VIOLATION
+            NotNullViolation.new(message)
           when SERIALIZATION_FAILURE
-            TransactionSerializationError.new(message)
+            SerializationFailure.new(message)
+          when DEADLOCK_DETECTED
+            Deadlocked.new(message)
+          when LOCK_NOT_AVAILABLE
+            LockWaitTimeout.new(message)
+          when QUERY_CANCELED
+            QueryCanceled.new(message)
           else
             super
           end
         end
 
-      private
-
-        def get_oid_type(oid, fmod, column_name, sql_type = '') # :nodoc:
+        def get_oid_type(oid, fmod, column_name, sql_type = "".freeze)
           if !type_map.key?(oid)
-            load_additional_types(type_map, [oid])
+            load_additional_types([oid])
           end
 
           type_map.fetch(oid, fmod, sql_type) {
             warn "unknown OID #{oid}: failed to recognize type of '#{column_name}'. It will be treated as String."
-            Type::Value.new.tap do |cast_type|
+            Type.default_value.tap do |cast_type|
               type_map.register_type(oid, cast_type)
             end
           }
         end
 
-        def initialize_type_map(m) # :nodoc:
-          register_class_with_limit m, 'int2', Type::Integer
-          register_class_with_limit m, 'int4', Type::Integer
-          register_class_with_limit m, 'int8', Type::Integer
-          m.alias_type 'oid', 'int2'
-          m.register_type 'float4', Type::Float.new
-          m.alias_type 'float8', 'float4'
-          m.register_type 'text', Type::Text.new
-          register_class_with_limit m, 'varchar', Type::String
-          m.alias_type 'char', 'varchar'
-          m.alias_type 'name', 'varchar'
-          m.alias_type 'bpchar', 'varchar'
-          m.register_type 'bool', Type::Boolean.new
-          register_class_with_limit m, 'bit', OID::Bit
-          register_class_with_limit m, 'varbit', OID::BitVarying
-          m.alias_type 'timestamptz', 'timestamp'
-          m.register_type 'date', Type::Date.new
-
-          m.register_type 'money', OID::Money.new
-          m.register_type 'bytea', OID::Bytea.new
-          m.register_type 'point', OID::Point.new
-          m.register_type 'hstore', OID::Hstore.new
-          m.register_type 'json', OID::Json.new
-          m.register_type 'jsonb', OID::Jsonb.new
-          m.register_type 'cidr', OID::Cidr.new
-          m.register_type 'inet', OID::Inet.new
-          m.register_type 'uuid', OID::Uuid.new
-          m.register_type 'xml', OID::Xml.new
-          m.register_type 'tsvector', OID::SpecializedString.new(:tsvector)
-          m.register_type 'macaddr', OID::SpecializedString.new(:macaddr)
-          m.register_type 'citext', OID::SpecializedString.new(:citext)
-          m.register_type 'ltree', OID::SpecializedString.new(:ltree)
-          m.register_type 'line', OID::SpecializedString.new(:line)
-          m.register_type 'lseg', OID::SpecializedString.new(:lseg)
-          m.register_type 'box', OID::SpecializedString.new(:box)
-          m.register_type 'path', OID::SpecializedString.new(:path)
-          m.register_type 'polygon', OID::SpecializedString.new(:polygon)
-          m.register_type 'circle', OID::SpecializedString.new(:circle)
-
-          # FIXME: why are we keeping these types as strings?
-          m.alias_type 'interval', 'varchar'
-
-          register_class_with_precision m, 'time', Type::Time
-          register_class_with_precision m, 'timestamp', OID::DateTime
-
-          m.register_type 'numeric' do |_, fmod, sql_type|
+        def initialize_type_map(m = type_map)
+          m.register_type "int2", Type::Integer.new(limit: 2)
+          m.register_type "int4", Type::Integer.new(limit: 4)
+          m.register_type "int8", Type::Integer.new(limit: 8)
+          m.register_type "oid", OID::Oid.new
+          m.register_type "float4", Type::Float.new
+          m.alias_type "float8", "float4"
+          m.register_type "text", Type::Text.new
+          register_class_with_limit m, "varchar", Type::String
+          m.alias_type "char", "varchar"
+          m.alias_type "name", "varchar"
+          m.alias_type "bpchar", "varchar"
+          m.register_type "bool", Type::Boolean.new
+          register_class_with_limit m, "bit", OID::Bit
+          register_class_with_limit m, "varbit", OID::BitVarying
+          m.alias_type "timestamptz", "timestamp"
+          m.register_type "date", Type::Date.new
+
+          m.register_type "money", OID::Money.new
+          m.register_type "bytea", OID::Bytea.new
+          m.register_type "point", OID::Point.new
+          m.register_type "hstore", OID::Hstore.new
+          m.register_type "json", Type::Json.new
+          m.register_type "jsonb", OID::Jsonb.new
+          m.register_type "cidr", OID::Cidr.new
+          m.register_type "inet", OID::Inet.new
+          m.register_type "uuid", OID::Uuid.new
+          m.register_type "xml", OID::Xml.new
+          m.register_type "tsvector", OID::SpecializedString.new(:tsvector)
+          m.register_type "macaddr", OID::SpecializedString.new(:macaddr)
+          m.register_type "citext", OID::SpecializedString.new(:citext)
+          m.register_type "ltree", OID::SpecializedString.new(:ltree)
+          m.register_type "line", OID::SpecializedString.new(:line)
+          m.register_type "lseg", OID::SpecializedString.new(:lseg)
+          m.register_type "box", OID::SpecializedString.new(:box)
+          m.register_type "path", OID::SpecializedString.new(:path)
+          m.register_type "polygon", OID::SpecializedString.new(:polygon)
+          m.register_type "circle", OID::SpecializedString.new(:circle)
+
+          m.register_type "interval" do |_, _, sql_type|
+            precision = extract_precision(sql_type)
+            OID::SpecializedString.new(:interval, precision: precision)
+          end
+
+          register_class_with_precision m, "time", Type::Time
+          register_class_with_precision m, "timestamp", OID::DateTime
+
+          m.register_type "numeric" do |_, fmod, sql_type|
             precision = extract_precision(sql_type)
             scale = extract_scale(sql_type)
 
@@ -505,56 +508,45 @@ module ActiveRecord
             end
           end
 
-          load_additional_types(m)
-        end
-
-        def extract_limit(sql_type) # :nodoc:
-          case sql_type
-          when /^bigint/i, /^int8/i
-            8
-          when /^smallint/i
-            2
-          else
-            super
-          end
+          load_additional_types
         end
 
         # Extracts the value from a PostgreSQL column default definition.
-        def extract_value_from_default(default) # :nodoc:
+        def extract_value_from_default(default)
           case default
             # Quoted types
-            when /\A[\(B]?'(.*)'.*::"?([\w. ]+)"?(?:\[\])?\z/m
-              # The default 'now'::date is CURRENT_DATE
-              if $1 == "now".freeze && $2 == "date".freeze
-                nil
-              else
-                $1.gsub("''".freeze, "'".freeze)
-              end
+          when /\A[\(B]?'(.*)'.*::"?([\w. ]+)"?(?:\[\])?\z/m
+            # The default 'now'::date is CURRENT_DATE
+            if $1 == "now".freeze && $2 == "date".freeze
+              nil
+            else
+              $1.gsub("''".freeze, "'".freeze)
+            end
             # Boolean types
-            when 'true'.freeze, 'false'.freeze
-              default
+          when "true".freeze, "false".freeze
+            default
             # Numeric types
-            when /\A\(?(-?\d+(\.\d*)?)\)?(::bigint)?\z/
-              $1
+          when /\A\(?(-?\d+(\.\d*)?)\)?(::bigint)?\z/
+            $1
             # Object identifier types
-            when /\A-?\d+\z/
-              $1
-            else
-              # Anything else is blank, some user type, or some function
-              # and we can't know the value of that, so return nil.
-              nil
+          when /\A-?\d+\z/
+            $1
+          else
+            # Anything else is blank, some user type, or some function
+            # and we can't know the value of that, so return nil.
+            nil
           end
         end
 
-        def extract_default_function(default_value, default) # :nodoc:
+        def extract_default_function(default_value, default)
           default if has_default_function?(default_value, default)
         end
 
-        def has_default_function?(default_value, default) # :nodoc:
-          !default_value && (%r{\w+\(.*\)|\(.*\)::\w+} === default)
+        def has_default_function?(default_value, default)
+          !default_value && %r{\w+\(.*\)|\(.*\)::\w+|CURRENT_DATE|CURRENT_TIMESTAMP}.match?(default)
         end
 
-        def load_additional_types(type_map, oids = nil) # :nodoc:
+        def load_additional_types(oids = nil)
           initializer = OID::TypeMapInitializer.new(type_map)
 
           if supports_ranges?
@@ -573,10 +565,10 @@ module ActiveRecord
           if oids
             query += "WHERE t.oid::integer IN (%s)" % oids.join(", ")
           else
-            query += initializer.query_conditions_for_initial_load(type_map)
+            query += initializer.query_conditions_for_initial_load
           end
 
-          execute_and_clear(query, 'SCHEMA', []) do |records|
+          execute_and_clear(query, "SCHEMA", []) do |records|
             initializer.run(records)
           end
         end
@@ -597,16 +589,22 @@ module ActiveRecord
         end
 
         def exec_no_cache(sql, name, binds)
-          type_casted_binds = binds.map { |attr| type_cast(attr.value_for_database) }
-          log(sql, name, binds) { @connection.async_exec(sql, type_casted_binds) }
+          type_casted_binds = type_casted_binds(binds)
+          log(sql, name, binds, type_casted_binds) do
+            ActiveSupport::Dependencies.interlock.permit_concurrent_loads do
+              @connection.async_exec(sql, type_casted_binds)
+            end
+          end
         end
 
         def exec_cache(sql, name, binds)
           stmt_key = prepare_statement(sql)
-          type_casted_binds = binds.map { |attr| type_cast(attr.value_for_database) }
+          type_casted_binds = type_casted_binds(binds)
 
-          log(sql, name, binds, stmt_key) do
-            @connection.exec_prepared(stmt_key, type_casted_binds)
+          log(sql, name, binds, type_casted_binds, stmt_key) do
+            ActiveSupport::Dependencies.interlock.permit_concurrent_loads do
+              @connection.exec_prepared(stmt_key, type_casted_binds)
+            end
           end
         rescue ActiveRecord::StatementInvalid => e
           raise unless is_cached_plan_failure?(e)
@@ -616,8 +614,10 @@ module ActiveRecord
           if in_transaction?
             raise ActiveRecord::PreparedStatementCacheExpired.new(e.cause.message)
           else
-            # outside of transactions we can simply flush this query and retry
-            @statements.delete sql_key(sql)
+            @lock.synchronize do
+              # outside of transactions we can simply flush this query and retry
+              @statements.delete sql_key(sql)
+            end
             retry
           end
         end
@@ -630,11 +630,11 @@ module ActiveRecord
         # ActiveRecord::PreparedStatementCacheExpired
         #
         # Check here for more details:
-        # http://git.postgresql.org/gitweb/?p=postgresql.git;a=blob;f=src/backend/utils/cache/plancache.c#l573
-        CACHED_PLAN_HEURISTIC = 'cached plan must not change result type'.freeze
+        # https://git.postgresql.org/gitweb/?p=postgresql.git;a=blob;f=src/backend/utils/cache/plancache.c#l573
+        CACHED_PLAN_HEURISTIC = "cached plan must not change result type".freeze
         def is_cached_plan_failure?(e)
           pgerror = e.cause
-          code = pgerror.result.result_error_field(PGresult::PG_DIAG_SQLSTATE)
+          code = pgerror.result.result_error_field(PG::PG_DIAG_SQLSTATE)
           code == FEATURE_NOT_SUPPORTED && pgerror.message.include?(CACHED_PLAN_HEURISTIC)
         rescue
           false
@@ -653,25 +653,27 @@ module ActiveRecord
         # Prepare the statement if it hasn't been prepared, return
         # the statement key.
         def prepare_statement(sql)
-          sql_key = sql_key(sql)
-          unless @statements.key? sql_key
-            nextkey = @statements.next_key
-            begin
-              @connection.prepare nextkey, sql
-            rescue => e
-              raise translate_exception_class(e, sql)
+          @lock.synchronize do
+            sql_key = sql_key(sql)
+            unless @statements.key? sql_key
+              nextkey = @statements.next_key
+              begin
+                @connection.prepare nextkey, sql
+              rescue => e
+                raise translate_exception_class(e, sql)
+              end
+              # Clear the queue
+              @connection.get_last_result
+              @statements[sql_key] = nextkey
             end
-            # Clear the queue
-            @connection.get_last_result
-            @statements[sql_key] = nextkey
+            @statements[sql_key]
           end
-          @statements[sql_key]
         end
 
         # Connects to a PostgreSQL server and sets up the adapter depending on the
         # connected server's characteristics.
         def connect
-          @connection = PGconn.connect(@connection_parameters)
+          @connection = PG.connect(@connection_parameters)
           configure_connection
         rescue ::PG::Error => error
           if error.message.include?("does not exist")
@@ -687,39 +689,36 @@ module ActiveRecord
           if @config[:encoding]
             @connection.set_client_encoding(@config[:encoding])
           end
-          self.client_min_messages = @config[:min_messages] || 'warning'
+          self.client_min_messages = @config[:min_messages] || "warning"
           self.schema_search_path = @config[:schema_search_path] || @config[:schema_order]
 
           # Use standard-conforming strings so we don't have to do the E'...' dance.
           set_standard_conforming_strings
 
+          variables = @config.fetch(:variables, {}).stringify_keys
+
           # If using Active Record's time zone support configure the connection to return
           # TIMESTAMP WITH ZONE types in UTC.
-          # (SET TIME ZONE does not use an equals sign like other SET variables)
-          if ActiveRecord::Base.default_timezone == :utc
-            execute("SET time zone 'UTC'", 'SCHEMA')
-          elsif @local_tz
-            execute("SET time zone '#{@local_tz}'", 'SCHEMA')
+          unless variables["timezone"]
+            if ActiveRecord::Base.default_timezone == :utc
+              variables["timezone"] = "UTC"
+            elsif @local_tz
+              variables["timezone"] = @local_tz
+            end
           end
 
           # SET statements from :variables config hash
-          # http://www.postgresql.org/docs/current/static/sql-set.html
-          variables = @config[:variables] || {}
+          # https://www.postgresql.org/docs/current/static/sql-set.html
           variables.map do |k, v|
-            if v == ':default' || v == :default
+            if v == ":default" || v == :default
               # Sets the value to the global or compile default
-              execute("SET SESSION #{k} TO DEFAULT", 'SCHEMA')
+              execute("SET SESSION #{k} TO DEFAULT", "SCHEMA")
             elsif !v.nil?
-              execute("SET SESSION #{k} TO #{quote(v)}", 'SCHEMA')
+              execute("SET SESSION #{k} TO #{quote(v)}", "SCHEMA")
             end
           end
         end
 
-        # Returns the current ID of a table's sequence.
-        def last_insert_id_result(sequence_name) # :nodoc:
-          exec_query("SELECT currval('#{sequence_name}')", 'SQL')
-        end
-
         # Returns the list of a table's column names, data types, and default values.
         #
         # The underlying query is roughly:
@@ -738,28 +737,28 @@ module ActiveRecord
         # Query implementation notes:
         #  - format_type includes the column size constraint, e.g. varchar(50)
         #  - ::regclass is a function that gives the id for a table name
-        def column_definitions(table_name) # :nodoc:
-          query(<<-end_sql, 'SCHEMA')
+        def column_definitions(table_name)
+          query(<<-end_sql, "SCHEMA")
               SELECT a.attname, format_type(a.atttypid, a.atttypmod),
                      pg_get_expr(d.adbin, d.adrelid), a.attnotnull, a.atttypid, a.atttypmod,
-             (SELECT c.collname FROM pg_collation c, pg_type t
-               WHERE c.oid = a.attcollation AND t.oid = a.atttypid AND a.attcollation <> t.typcollation),
-                     col_description(a.attrelid, a.attnum) AS comment
-                FROM pg_attribute a LEFT JOIN pg_attrdef d
-                  ON a.attrelid = d.adrelid AND a.attnum = d.adnum
-               WHERE a.attrelid = '#{quote_table_name(table_name)}'::regclass
+                     c.collname, col_description(a.attrelid, a.attnum) AS comment
+                FROM pg_attribute a
+                LEFT JOIN pg_attrdef d ON a.attrelid = d.adrelid AND a.attnum = d.adnum
+                LEFT JOIN pg_type t ON a.atttypid = t.oid
+                LEFT JOIN pg_collation c ON a.attcollation = c.oid AND a.attcollation <> t.typcollation
+               WHERE a.attrelid = #{quote(quote_table_name(table_name))}::regclass
                  AND a.attnum > 0 AND NOT a.attisdropped
                ORDER BY a.attnum
           end_sql
         end
 
-        def extract_table_ref_from_insert_sql(sql) # :nodoc:
+        def extract_table_ref_from_insert_sql(sql)
           sql[/into\s("[A-Za-z0-9_."\[\]\s]+"|[A-Za-z0-9_."\[\]]+)\s*/im]
           $1.strip if $1
         end
 
-        def create_table_definition(*args) # :nodoc:
-          PostgreSQL::TableDefinition.new(*args)
+        def arel_visitor
+          Arel::Visitors::PostgreSQL.new(self)
         end
 
         def can_perform_case_insensitive_comparison_for?(column)
@@ -768,10 +767,14 @@ module ActiveRecord
             sql = <<-end_sql
               SELECT exists(
                 SELECT * FROM pg_proc
+                WHERE proname = 'lower'
+                  AND proargtypes = ARRAY[#{quote column.sql_type}::regtype]::oidvector
+              ) OR exists(
+                SELECT * FROM pg_proc
                 INNER JOIN pg_cast
-                  ON casttarget::text::oidvector = proargtypes
+                  ON ARRAY[casttarget]::oidvector = proargtypes
                 WHERE proname = 'lower'
-                  AND castsource = '#{column.sql_type}'::regtype::oid
+                  AND castsource = #{quote column.sql_type}::regtype
               )
             end_sql
             execute_and_clear(sql, "SCHEMA", []) do |result|
@@ -785,19 +788,18 @@ module ActiveRecord
           map[Integer] = PG::TextEncoder::Integer.new
           map[TrueClass] = PG::TextEncoder::Boolean.new
           map[FalseClass] = PG::TextEncoder::Boolean.new
-          map[Float] = PG::TextEncoder::Float.new
           @connection.type_map_for_queries = map
         end
 
         def add_pg_decoders
           coders_by_name = {
-            'int2' => PG::TextDecoder::Integer,
-            'int4' => PG::TextDecoder::Integer,
-            'int8' => PG::TextDecoder::Integer,
-            'oid' => PG::TextDecoder::Integer,
-            'float4' => PG::TextDecoder::Float,
-            'float8' => PG::TextDecoder::Float,
-            'bool' => PG::TextDecoder::Boolean,
+            "int2" => PG::TextDecoder::Integer,
+            "int4" => PG::TextDecoder::Integer,
+            "int8" => PG::TextDecoder::Integer,
+            "oid" => PG::TextDecoder::Integer,
+            "float4" => PG::TextDecoder::Float,
+            "float8" => PG::TextDecoder::Float,
+            "bool" => PG::TextDecoder::Boolean,
           }
           known_coder_types = coders_by_name.keys.map { |n| quote(n) }
           query = <<-SQL % known_coder_types.join(", ")
@@ -807,7 +809,7 @@ module ActiveRecord
           SQL
           coders = execute_and_clear(query, "SCHEMA", []) do |result|
             result
-              .map { |row| construct_coder(row, coders_by_name[row['typname']]) }
+              .map { |row| construct_coder(row, coders_by_name[row["typname"]]) }
               .compact
           end
 
@@ -818,7 +820,7 @@ module ActiveRecord
 
         def construct_coder(row, coder_class)
           return unless coder_class
-          coder_class.new(oid: row['oid'].to_i, name: row['typname'])
+          coder_class.new(oid: row["oid"].to_i, name: row["typname"])
         end
 
         ActiveRecord::Type.add_modifier({ array: true }, OID::Array, adapter: :postgresql)
@@ -832,11 +834,10 @@ module ActiveRecord
         ActiveRecord::Type.register(:enum, OID::Enum, adapter: :postgresql)
         ActiveRecord::Type.register(:hstore, OID::Hstore, adapter: :postgresql)
         ActiveRecord::Type.register(:inet, OID::Inet, adapter: :postgresql)
-        ActiveRecord::Type.register(:json, OID::Json, adapter: :postgresql)
         ActiveRecord::Type.register(:jsonb, OID::Jsonb, adapter: :postgresql)
         ActiveRecord::Type.register(:money, OID::Money, adapter: :postgresql)
-        ActiveRecord::Type.register(:point, OID::Rails51Point, adapter: :postgresql)
-        ActiveRecord::Type.register(:legacy_point, OID::Point, adapter: :postgresql)
+        ActiveRecord::Type.register(:point, OID::Point, adapter: :postgresql)
+        ActiveRecord::Type.register(:legacy_point, OID::LegacyPoint, adapter: :postgresql)
         ActiveRecord::Type.register(:uuid, OID::Uuid, adapter: :postgresql)
         ActiveRecord::Type.register(:vector, OID::Vector, adapter: :postgresql)
         ActiveRecord::Type.register(:xml, OID::Xml, adapter: :postgresql)
diff --git a/activerecord/lib/active_record/connection_adapters/schema_cache.rb b/activerecord/lib/active_record/connection_adapters/schema_cache.rb
index eee142378c..f34b6733da 100644
--- a/activerecord/lib/active_record/connection_adapters/schema_cache.rb
+++ b/activerecord/lib/active_record/connection_adapters/schema_cache.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActiveRecord
   module ConnectionAdapters
     class SchemaCache
@@ -21,6 +23,22 @@ module ActiveRecord
         @data_sources = @data_sources.dup
       end
 
+      def encode_with(coder)
+        coder["columns"] = @columns
+        coder["columns_hash"] = @columns_hash
+        coder["primary_keys"] = @primary_keys
+        coder["data_sources"] = @data_sources
+        coder["version"] = ActiveRecord::Migrator.current_version
+      end
+
+      def init_with(coder)
+        @columns = coder["columns"]
+        @columns_hash = coder["columns_hash"]
+        @primary_keys = coder["primary_keys"]
+        @data_sources = coder["data_sources"]
+        @version = coder["version"]
+      end
+
       def primary_keys(table_name)
         @primary_keys[table_name] ||= data_source_exists?(table_name) ? connection.primary_key(table_name) : nil
       end
@@ -32,9 +50,6 @@ module ActiveRecord
 
         @data_sources[name] = connection.data_source_exists?(name)
       end
-      alias table_exists? data_source_exists?
-      deprecate :table_exists? => "use #data_source_exists? instead"
-
 
       # Add internal cache for table with +table_name+.
       def add(table_name)
@@ -48,8 +63,6 @@ module ActiveRecord
       def data_sources(name)
         @data_sources[name]
       end
-      alias tables data_sources
-      deprecate :tables => "use #data_sources instead"
 
       # Get the columns for a table
       def columns(table_name)
@@ -84,8 +97,6 @@ module ActiveRecord
         @primary_keys.delete name
         @data_sources.delete name
       end
-      alias clear_table_cache! clear_data_source_cache!
-      deprecate :clear_table_cache! => "use #clear_data_source_cache! instead"
 
       def marshal_dump
         # if we get current version during initialization, it happens stack over flow.
diff --git a/activerecord/lib/active_record/connection_adapters/sql_type_metadata.rb b/activerecord/lib/active_record/connection_adapters/sql_type_metadata.rb
index ccb7e154ee..8489bcbf1d 100644
--- a/activerecord/lib/active_record/connection_adapters/sql_type_metadata.rb
+++ b/activerecord/lib/active_record/connection_adapters/sql_type_metadata.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActiveRecord
   # :stopdoc:
   module ConnectionAdapters
@@ -24,9 +26,9 @@ module ActiveRecord
 
       protected
 
-      def attributes_for_hash
-        [self.class, sql_type, type, limit, precision, scale]
-      end
+        def attributes_for_hash
+          [self.class, sql_type, type, limit, precision, scale]
+        end
     end
   end
 end
diff --git a/activerecord/lib/active_record/connection_adapters/sqlite3/explain_pretty_printer.rb b/activerecord/lib/active_record/connection_adapters/sqlite3/explain_pretty_printer.rb
index a946f5ebd0..832fdfe5c4 100644
--- a/activerecord/lib/active_record/connection_adapters/sqlite3/explain_pretty_printer.rb
+++ b/activerecord/lib/active_record/connection_adapters/sqlite3/explain_pretty_printer.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActiveRecord
   module ConnectionAdapters
     module SQLite3
@@ -10,7 +12,7 @@ module ActiveRecord
         #
         def pp(result)
           result.rows.map do |row|
-            row.join('|')
+            row.join("|")
           end.join("\n") + "\n"
         end
       end
diff --git a/activerecord/lib/active_record/connection_adapters/sqlite3/quoting.rb b/activerecord/lib/active_record/connection_adapters/sqlite3/quoting.rb
index d5a181d3e2..8042dbfea2 100644
--- a/activerecord/lib/active_record/connection_adapters/sqlite3/quoting.rb
+++ b/activerecord/lib/active_record/connection_adapters/sqlite3/quoting.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActiveRecord
   module ConnectionAdapters
     module SQLite3
@@ -11,37 +13,49 @@ module ActiveRecord
         end
 
         def quote_column_name(name)
-          @quoted_column_names[name] ||= %Q("#{super.gsub('"', '""')}")
+          @quoted_column_names[name] ||= %Q("#{super.gsub('"', '""')}").freeze
         end
 
         def quoted_time(value)
           quoted_date(value)
         end
 
-        private
+        def quoted_binary(value)
+          "x'#{value.hex}'"
+        end
 
-        def _quote(value)
-          if value.is_a?(Type::Binary::Data)
-            "x'#{value.hex}'"
-          else
-            super
-          end
+        def quoted_true
+          ActiveRecord::ConnectionAdapters::SQLite3Adapter.represent_boolean_as_integer ? "1".freeze : "'t'".freeze
         end
 
-        def _type_cast(value)
-          case value
-          when BigDecimal
-            value.to_f
-          when String
-            if value.encoding == Encoding::ASCII_8BIT
-              super(value.encode(Encoding::UTF_8))
+        def unquoted_true
+          ActiveRecord::ConnectionAdapters::SQLite3Adapter.represent_boolean_as_integer ? 1 : "t".freeze
+        end
+
+        def quoted_false
+          ActiveRecord::ConnectionAdapters::SQLite3Adapter.represent_boolean_as_integer ? "0".freeze : "'f'".freeze
+        end
+
+        def unquoted_false
+          ActiveRecord::ConnectionAdapters::SQLite3Adapter.represent_boolean_as_integer ? 0 : "f".freeze
+        end
+
+        private
+
+          def _type_cast(value)
+            case value
+            when BigDecimal
+              value.to_f
+            when String
+              if value.encoding == Encoding::ASCII_8BIT
+                super(value.encode(Encoding::UTF_8))
+              else
+                super
+              end
             else
               super
             end
-          else
-            super
           end
-        end
       end
     end
   end
diff --git a/activerecord/lib/active_record/connection_adapters/sqlite3/schema_creation.rb b/activerecord/lib/active_record/connection_adapters/sqlite3/schema_creation.rb
index 70c0d28830..b842561317 100644
--- a/activerecord/lib/active_record/connection_adapters/sqlite3/schema_creation.rb
+++ b/activerecord/lib/active_record/connection_adapters/sqlite3/schema_creation.rb
@@ -1,15 +1,10 @@
+# frozen_string_literal: true
+
 module ActiveRecord
   module ConnectionAdapters
     module SQLite3
-      class SchemaCreation < AbstractAdapter::SchemaCreation
+      class SchemaCreation < AbstractAdapter::SchemaCreation # :nodoc:
         private
-
-          def column_options(o)
-            options = super
-            options[:null] = false if o.primary_key
-            options
-          end
-
           def add_column_options!(sql, options)
             if options[:collation]
               sql << " COLLATE \"#{options[:collation]}\""
diff --git a/activerecord/lib/active_record/connection_adapters/sqlite3/schema_definitions.rb b/activerecord/lib/active_record/connection_adapters/sqlite3/schema_definitions.rb
new file mode 100644
index 0000000000..c9855019c1
--- /dev/null
+++ b/activerecord/lib/active_record/connection_adapters/sqlite3/schema_definitions.rb
@@ -0,0 +1,19 @@
+# frozen_string_literal: true
+
+module ActiveRecord
+  module ConnectionAdapters
+    module SQLite3
+      class TableDefinition < ActiveRecord::ConnectionAdapters::TableDefinition
+        def references(*args, **options)
+          super(*args, type: :integer, **options)
+        end
+        alias :belongs_to :references
+
+        private
+          def integer_like_primary_key_type(type, options)
+            :primary_key
+          end
+      end
+    end
+  end
+end
diff --git a/activerecord/lib/active_record/connection_adapters/sqlite3/schema_dumper.rb b/activerecord/lib/active_record/connection_adapters/sqlite3/schema_dumper.rb
new file mode 100644
index 0000000000..621678ec65
--- /dev/null
+++ b/activerecord/lib/active_record/connection_adapters/sqlite3/schema_dumper.rb
@@ -0,0 +1,18 @@
+# frozen_string_literal: true
+
+module ActiveRecord
+  module ConnectionAdapters
+    module SQLite3
+      class SchemaDumper < ConnectionAdapters::SchemaDumper # :nodoc:
+        private
+          def default_primary_key?(column)
+            schema_type(column) == :integer
+          end
+
+          def explicit_primary_key_default?(column)
+            column.bigint?
+          end
+      end
+    end
+  end
+end
diff --git a/activerecord/lib/active_record/connection_adapters/sqlite3/schema_statements.rb b/activerecord/lib/active_record/connection_adapters/sqlite3/schema_statements.rb
new file mode 100644
index 0000000000..58e5138e02
--- /dev/null
+++ b/activerecord/lib/active_record/connection_adapters/sqlite3/schema_statements.rb
@@ -0,0 +1,102 @@
+# frozen_string_literal: true
+
+module ActiveRecord
+  module ConnectionAdapters
+    module SQLite3
+      module SchemaStatements # :nodoc:
+        # Returns an array of indexes for the given table.
+        def indexes(table_name)
+          exec_query("PRAGMA index_list(#{quote_table_name(table_name)})", "SCHEMA").map do |row|
+            index_sql = query_value(<<-SQL, "SCHEMA")
+              SELECT sql
+              FROM sqlite_master
+              WHERE name = #{quote(row['name'])} AND type = 'index'
+              UNION ALL
+              SELECT sql
+              FROM sqlite_temp_master
+              WHERE name = #{quote(row['name'])} AND type = 'index'
+            SQL
+
+            /\sWHERE\s+(?<where>.+)$/i =~ index_sql
+
+            columns = exec_query("PRAGMA index_info(#{quote(row['name'])})", "SCHEMA").map do |col|
+              col["name"]
+            end
+
+            # Add info on sort order for columns (only desc order is explicitly specified, asc is
+            # the default)
+            orders = {}
+            if index_sql # index_sql can be null in case of primary key indexes
+              index_sql.scan(/"(\w+)" DESC/).flatten.each { |order_column|
+                orders[order_column] = :desc
+              }
+            end
+
+            IndexDefinition.new(
+              table_name,
+              row["name"],
+              row["unique"] != 0,
+              columns,
+              where: where,
+              orders: orders
+            )
+          end
+        end
+
+        def create_schema_dumper(options)
+          SQLite3::SchemaDumper.create(self, options)
+        end
+
+        private
+          def schema_creation
+            SQLite3::SchemaCreation.new(self)
+          end
+
+          def create_table_definition(*args)
+            SQLite3::TableDefinition.new(*args)
+          end
+
+          def new_column_from_field(table_name, field)
+            default = \
+              case field["dflt_value"]
+              when /^null$/i
+                nil
+              when /^'(.*)'$/m
+                $1.gsub("''", "'")
+              when /^"(.*)"$/m
+                $1.gsub('""', '"')
+              else
+                field["dflt_value"]
+              end
+
+            type_metadata = fetch_type_metadata(field["type"])
+            Column.new(field["name"], default, type_metadata, field["notnull"].to_i == 0, table_name, nil, field["collation"])
+          end
+
+          def data_source_sql(name = nil, type: nil)
+            scope = quoted_scope(name, type: type)
+            scope[:type] ||= "'table','view'"
+
+            sql = "SELECT name FROM sqlite_master WHERE name <> 'sqlite_sequence'".dup
+            sql << " AND name = #{scope[:name]}" if scope[:name]
+            sql << " AND type IN (#{scope[:type]})"
+            sql
+          end
+
+          def quoted_scope(name = nil, type: nil)
+            type = \
+              case type
+              when "BASE TABLE"
+                "'table'"
+              when "VIEW"
+                "'view'"
+              end
+            scope = {}
+            scope[:name] = quote(name) if name
+            scope[:type] = type if type
+            scope
+          end
+      end
+    end
+  end
+end
diff --git a/activerecord/lib/active_record/connection_adapters/sqlite3_adapter.rb b/activerecord/lib/active_record/connection_adapters/sqlite3_adapter.rb
index eb2268157b..441c7cd28f 100644
--- a/activerecord/lib/active_record/connection_adapters/sqlite3_adapter.rb
+++ b/activerecord/lib/active_record/connection_adapters/sqlite3_adapter.rb
@@ -1,11 +1,16 @@
-require 'active_record/connection_adapters/abstract_adapter'
-require 'active_record/connection_adapters/statement_pool'
-require 'active_record/connection_adapters/sqlite3/explain_pretty_printer'
-require 'active_record/connection_adapters/sqlite3/quoting'
-require 'active_record/connection_adapters/sqlite3/schema_creation'
+# frozen_string_literal: true
 
-gem 'sqlite3', '~> 1.3.6'
-require 'sqlite3'
+require "active_record/connection_adapters/abstract_adapter"
+require "active_record/connection_adapters/statement_pool"
+require "active_record/connection_adapters/sqlite3/explain_pretty_printer"
+require "active_record/connection_adapters/sqlite3/quoting"
+require "active_record/connection_adapters/sqlite3/schema_creation"
+require "active_record/connection_adapters/sqlite3/schema_definitions"
+require "active_record/connection_adapters/sqlite3/schema_dumper"
+require "active_record/connection_adapters/sqlite3/schema_statements"
+
+gem "sqlite3", "~> 1.3.6"
+require "sqlite3"
 
 module ActiveRecord
   module ConnectionHandling # :nodoc:
@@ -18,7 +23,7 @@ module ActiveRecord
       # Allow database path relative to Rails.root, but only if the database
       # path is not the special path that tells sqlite to build a database only
       # in memory.
-      if ':memory:' != config[:database]
+      if ":memory:" != config[:database]
         config[:database] = File.expand_path(config[:database], Rails.root) if defined?(Rails.root)
         dirname = File.dirname(config[:database])
         Dir.mkdir(dirname) unless File.directory?(dirname)
@@ -26,7 +31,7 @@ module ActiveRecord
 
       db = SQLite3::Database.new(
         config[:database].to_s,
-        :results_as_hash => true
+        results_as_hash: true
       )
 
       db.busy_timeout(ConnectionAdapters::SQLite3Adapter.type_cast_config_to_integer(config[:timeout])) if config[:timeout]
@@ -49,12 +54,13 @@ module ActiveRecord
     #
     # * <tt>:database</tt> - Path to the database file.
     class SQLite3Adapter < AbstractAdapter
-      ADAPTER_NAME = 'SQLite'.freeze
+      ADAPTER_NAME = "SQLite".freeze
 
       include SQLite3::Quoting
+      include SQLite3::SchemaStatements
 
       NATIVE_DATABASE_TYPES = {
-        primary_key:  'INTEGER PRIMARY KEY AUTOINCREMENT NOT NULL',
+        primary_key:  "integer PRIMARY KEY AUTOINCREMENT NOT NULL",
         string:       { name: "varchar" },
         text:         { name: "text" },
         integer:      { name: "integer" },
@@ -64,23 +70,32 @@ module ActiveRecord
         time:         { name: "time" },
         date:         { name: "date" },
         binary:       { name: "blob" },
-        boolean:      { name: "boolean" }
+        boolean:      { name: "boolean" },
+        json:         { name: "json" },
       }
 
-      class StatementPool < ConnectionAdapters::StatementPool
-        private
-
-        def dealloc(stmt)
-          stmt[:stmt].close unless stmt[:stmt].closed?
-        end
-      end
-
-      def schema_creation # :nodoc:
-        SQLite3::SchemaCreation.new self
-      end
+      ##
+      # :singleton-method:
+      # Indicates whether boolean values are stored in sqlite3 databases as 1
+      # and 0 or 't' and 'f'. Leaving <tt>ActiveRecord::ConnectionAdapters::SQLite3Adapter.represent_boolean_as_integer</tt>
+      # set to false is deprecated. SQLite databases have used 't' and 'f' to
+      # serialize boolean values and must have old data converted to 1 and 0
+      # (its native boolean serialization) before setting this flag to true.
+      # Conversion can be accomplished by setting up a rake task which runs
+      #
+      #   ExampleModel.where("boolean_column = 't'").update_all(boolean_column: 1)
+      #   ExampleModel.where("boolean_column = 'f'").update_all(boolean_column: 0)
+      # for all models and all boolean columns, after which the flag must be set
+      # to true by adding the following to your <tt>application.rb</tt> file:
+      #
+      #   Rails.application.config.active_record.sqlite3.represent_boolean_as_integer = true
+      class_attribute :represent_boolean_as_integer, default: false
 
-      def arel_visitor # :nodoc:
-        Arel::Visitors::SQLite.new(self)
+      class StatementPool < ConnectionAdapters::StatementPool # :nodoc:
+        private
+          def dealloc(stmt)
+            stmt[:stmt].close unless stmt[:stmt].closed?
+          end
       end
 
       def initialize(connection, logger, connection_options, config)
@@ -88,6 +103,8 @@ module ActiveRecord
 
         @active     = nil
         @statements = StatementPool.new(self.class.type_cast_config_to_integer(config[:statement_limit]))
+
+        configure_connection
       end
 
       def supports_ddl_transactions?
@@ -99,38 +116,31 @@ module ActiveRecord
       end
 
       def supports_partial_index?
-        sqlite_version >= '3.8.0'
-      end
-
-      # Returns true, since this connection adapter supports prepared statement
-      # caching.
-      def supports_statement_cache?
-        true
+        sqlite_version >= "3.8.0"
       end
 
-      # Returns true, since this connection adapter supports migrations.
-      def supports_migrations? #:nodoc:
+      def requires_reloading?
         true
       end
 
-      def supports_primary_key? #:nodoc:
-        true
+      def supports_foreign_keys_in_create?
+        sqlite_version >= "3.6.19"
       end
 
-      def requires_reloading?
+      def supports_views?
         true
       end
 
-      def supports_views?
+      def supports_datetime_with_precision?
         true
       end
 
-      def supports_datetime_with_precision?
+      def supports_json?
         true
       end
 
       def supports_multi_insert?
-        sqlite_version >= '3.7.11'
+        sqlite_version >= "3.7.11"
       end
 
       def active?
@@ -154,12 +164,8 @@ module ActiveRecord
         true
       end
 
-      def valid_type?(type)
-        true
-      end
-
       # Returns 62. SQLite supports index names up to 64
-      # characters. The rest is used by rails internally to perform
+      # characters. The rest is used by Rails internally to perform
       # temporary rename operations
       def allowed_index_name_length
         index_name_length - 2
@@ -178,47 +184,62 @@ module ActiveRecord
         true
       end
 
+      # REFERENTIAL INTEGRITY ====================================
+
+      def disable_referential_integrity # :nodoc:
+        old = query_value("PRAGMA foreign_keys")
+
+        begin
+          execute("PRAGMA foreign_keys = OFF")
+          yield
+        ensure
+          execute("PRAGMA foreign_keys = #{old}")
+        end
+      end
+
       #--
       # DATABASE STATEMENTS ======================================
       #++
 
       def explain(arel, binds = [])
         sql = "EXPLAIN QUERY PLAN #{to_sql(arel, binds)}"
-        SQLite3::ExplainPrettyPrinter.new.pp(exec_query(sql, 'EXPLAIN', []))
+        SQLite3::ExplainPrettyPrinter.new.pp(exec_query(sql, "EXPLAIN", []))
       end
 
       def exec_query(sql, name = nil, binds = [], prepare: false)
-        type_casted_binds = binds.map { |attr| type_cast(attr.value_for_database) }
-
-        log(sql, name, binds) do
-          # Don't cache statements if they are not prepared
-          unless prepare
-            stmt    = @connection.prepare(sql)
-            begin
-              cols    = stmt.columns
-              unless without_prepared_statement?(binds)
-                stmt.bind_params(type_casted_binds)
+        type_casted_binds = type_casted_binds(binds)
+
+        log(sql, name, binds, type_casted_binds) do
+          ActiveSupport::Dependencies.interlock.permit_concurrent_loads do
+            # Don't cache statements if they are not prepared
+            unless prepare
+              stmt = @connection.prepare(sql)
+              begin
+                cols = stmt.columns
+                unless without_prepared_statement?(binds)
+                  stmt.bind_params(type_casted_binds)
+                end
+                records = stmt.to_a
+              ensure
+                stmt.close
               end
+            else
+              cache = @statements[sql] ||= {
+                stmt: @connection.prepare(sql)
+              }
+              stmt = cache[:stmt]
+              cols = cache[:cols] ||= stmt.columns
+              stmt.reset!
+              stmt.bind_params(type_casted_binds)
               records = stmt.to_a
-            ensure
-              stmt.close
             end
-            stmt = records
-          else
-            cache = @statements[sql] ||= {
-              :stmt => @connection.prepare(sql)
-            }
-            stmt = cache[:stmt]
-            cols = cache[:cols] ||= stmt.columns
-            stmt.reset!
-            stmt.bind_params(type_casted_binds)
-          end
 
-          ActiveRecord::Result.new(cols, stmt.to_a)
+            ActiveRecord::Result.new(cols, records)
+          end
         end
       end
 
-      def exec_delete(sql, name = 'SQL', binds = [])
+      def exec_delete(sql, name = "SQL", binds = [])
         exec_query(sql, name, binds)
         @connection.changes
       end
@@ -229,123 +250,30 @@ module ActiveRecord
       end
 
       def execute(sql, name = nil) #:nodoc:
-        log(sql, name) { @connection.execute(sql) }
+        log(sql, name) do
+          ActiveSupport::Dependencies.interlock.permit_concurrent_loads do
+            @connection.execute(sql)
+          end
+        end
       end
 
       def begin_db_transaction #:nodoc:
-        log('begin transaction',nil) { @connection.transaction }
+        log("begin transaction", nil) { @connection.transaction }
       end
 
       def commit_db_transaction #:nodoc:
-        log('commit transaction',nil) { @connection.commit }
+        log("commit transaction", nil) { @connection.commit }
       end
 
       def exec_rollback_db_transaction #:nodoc:
-        log('rollback transaction',nil) { @connection.rollback }
+        log("rollback transaction", nil) { @connection.rollback }
       end
 
       # SCHEMA STATEMENTS ========================================
 
-      def tables(name = nil) # :nodoc:
-        ActiveSupport::Deprecation.warn(<<-MSG.squish)
-          #tables currently returns both tables and views.
-          This behavior is deprecated and will be changed with Rails 5.1 to only return tables.
-          Use #data_sources instead.
-        MSG
-
-        if name
-          ActiveSupport::Deprecation.warn(<<-MSG.squish)
-            Passing arguments to #tables is deprecated without replacement.
-          MSG
-        end
-
-        data_sources
-      end
-
-      def data_sources
-        select_values("SELECT name FROM sqlite_master WHERE type IN ('table','view') AND name <> 'sqlite_sequence'", 'SCHEMA')
-      end
-
-      def table_exists?(table_name)
-        ActiveSupport::Deprecation.warn(<<-MSG.squish)
-          #table_exists? currently checks both tables and views.
-          This behavior is deprecated and will be changed with Rails 5.1 to only check tables.
-          Use #data_source_exists? instead.
-        MSG
-
-        data_source_exists?(table_name)
-      end
-
-      def data_source_exists?(table_name)
-        return false unless table_name.present?
-
-        sql = "SELECT name FROM sqlite_master WHERE type IN ('table','view') AND name <> 'sqlite_sequence'"
-        sql << " AND name = #{quote(table_name)}"
-
-        select_values(sql, 'SCHEMA').any?
-      end
-
-      def views # :nodoc:
-        select_values("SELECT name FROM sqlite_master WHERE type = 'view' AND name <> 'sqlite_sequence'", 'SCHEMA')
-      end
-
-      def view_exists?(view_name) # :nodoc:
-        return false unless view_name.present?
-
-        sql = "SELECT name FROM sqlite_master WHERE type = 'view' AND name <> 'sqlite_sequence'"
-        sql << " AND name = #{quote(view_name)}"
-
-        select_values(sql, 'SCHEMA').any?
-      end
-
-      # Returns an array of +Column+ objects for the table specified by +table_name+.
-      def columns(table_name) # :nodoc:
-        table_name = table_name.to_s
-        table_structure(table_name).map do |field|
-          case field["dflt_value"]
-          when /^null$/i
-            field["dflt_value"] = nil
-          when /^'(.*)'$/m
-            field["dflt_value"] = $1.gsub("''", "'")
-          when /^"(.*)"$/m
-            field["dflt_value"] = $1.gsub('""', '"')
-          end
-
-          collation = field['collation']
-          sql_type = field['type']
-          type_metadata = fetch_type_metadata(sql_type)
-          new_column(field['name'], field['dflt_value'], type_metadata, field['notnull'].to_i == 0, table_name, nil, collation)
-        end
-      end
-
-      # Returns an array of indexes for the given table.
-      def indexes(table_name, name = nil) #:nodoc:
-        exec_query("PRAGMA index_list(#{quote_table_name(table_name)})", 'SCHEMA').map do |row|
-          sql = <<-SQL
-            SELECT sql
-            FROM sqlite_master
-            WHERE name=#{quote(row['name'])} AND type='index'
-            UNION ALL
-            SELECT sql
-            FROM sqlite_temp_master
-            WHERE name=#{quote(row['name'])} AND type='index'
-          SQL
-          index_sql = exec_query(sql).first['sql']
-          match = /\sWHERE\s+(.+)$/i.match(index_sql)
-          where = match[1] if match
-          IndexDefinition.new(
-            table_name,
-            row['name'],
-            row['unique'] != 0,
-            exec_query("PRAGMA index_info('#{row['name']}')", "SCHEMA").map { |col|
-              col['name']
-            }, nil, nil, where)
-        end
-      end
-
       def primary_keys(table_name) # :nodoc:
-        pks = table_structure(table_name).select { |f| f['pk'] > 0 }
-        pks.sort_by { |f| f['pk'] }.map { |f| f['name'] }
+        pks = table_structure(table_name).select { |f| f["pk"] > 0 }
+        pks.sort_by { |f| f["pk"] }.map { |f| f["name"] }
       end
 
       def remove_index(table_name, options = {}) #:nodoc:
@@ -362,14 +290,14 @@ module ActiveRecord
         rename_table_indexes(table_name, new_name)
       end
 
-      # See: http://www.sqlite.org/lang_altertable.html
+      # See: https://www.sqlite.org/lang_altertable.html
       # SQLite has an additional restriction on the ALTER TABLE statement
       def valid_alter_table_type?(type)
         type.to_sym != :primary_key
       end
 
       def add_column(table_name, column_name, type, options = {}) #:nodoc:
-        if valid_alter_table_type?(type)
+        if valid_alter_table_type?(type) && !options[:primary_key]
           super(table_name, column_name, type, options)
         else
           alter_table(table_name) do |definition|
@@ -403,14 +331,13 @@ module ActiveRecord
 
       def change_column(table_name, column_name, type, options = {}) #:nodoc:
         alter_table(table_name) do |definition|
-          include_default = options_include_default?(options)
           definition[column_name].instance_eval do
             self.type    = type
             self.limit   = options[:limit] if options.include?(:limit)
-            self.default = options[:default] if include_default
+            self.default = options[:default] if options.include?(:default)
             self.null    = options[:null] if options.include?(:null)
             self.precision = options[:precision] if options.include?(:precision)
-            self.scale   = options[:scale] if options.include?(:scale)
+            self.scale = options[:scale] if options.include?(:scale)
             self.collation = options[:collation] if options.include?(:collation)
           end
         end
@@ -418,51 +345,83 @@ module ActiveRecord
 
       def rename_column(table_name, column_name, new_column_name) #:nodoc:
         column = column_for(table_name, column_name)
-        alter_table(table_name, rename: {column.name => new_column_name.to_s})
+        alter_table(table_name, rename: { column.name => new_column_name.to_s })
         rename_column_indexes(table_name, column.name, new_column_name)
       end
 
-      protected
+      def add_reference(table_name, ref_name, **options) # :nodoc:
+        super(table_name, ref_name, type: :integer, **options)
+      end
+      alias :add_belongs_to :add_reference
+
+      def foreign_keys(table_name)
+        fk_info = exec_query("PRAGMA foreign_key_list(#{quote(table_name)})", "SCHEMA")
+        fk_info.map do |row|
+          options = {
+            column: row["from"],
+            primary_key: row["to"],
+            on_delete: extract_foreign_key_action(row["on_delete"]),
+            on_update: extract_foreign_key_action(row["on_update"])
+          }
+          ForeignKeyDefinition.new(table_name, row["table"], options)
+        end
+      end
+
+      def insert_fixtures(rows, table_name)
+        rows.each do |row|
+          insert_fixture(row, table_name)
+        end
+      end
+
+      private
+        def initialize_type_map(m = type_map)
+          super
+          register_class_with_limit m, %r(int)i, SQLite3Integer
+        end
 
         def table_structure(table_name)
-          structure = exec_query("PRAGMA table_info(#{quote_table_name(table_name)})", 'SCHEMA')
+          structure = exec_query("PRAGMA table_info(#{quote_table_name(table_name)})", "SCHEMA")
           raise(ActiveRecord::StatementInvalid, "Could not find table '#{table_name}'") if structure.empty?
           table_structure_with_collation(table_name, structure)
         end
+        alias column_definitions table_structure
 
-        def alter_table(table_name, options = {}) #:nodoc:
+        def alter_table(table_name, options = {})
           altered_table_name = "a#{table_name}"
-          caller = lambda {|definition| yield definition if block_given?}
+          caller = lambda { |definition| yield definition if block_given? }
 
           transaction do
             move_table(table_name, altered_table_name,
-              options.merge(:temporary => true))
+              options.merge(temporary: true))
             move_table(altered_table_name, table_name, &caller)
           end
         end
 
-        def move_table(from, to, options = {}, &block) #:nodoc:
+        def move_table(from, to, options = {}, &block)
           copy_table(from, to, options, &block)
           drop_table(from)
         end
 
-        def copy_table(from, to, options = {}) #:nodoc:
+        def copy_table(from, to, options = {})
           from_primary_key = primary_key(from)
           options[:id] = false
           create_table(to, options) do |definition|
             @definition = definition
-            @definition.primary_key(from_primary_key) if from_primary_key.present?
+            if from_primary_key.is_a?(Array)
+              @definition.primary_keys from_primary_key
+            end
             columns(from).each do |column|
               column_name = options[:rename] ?
                 (options[:rename][column.name] ||
                  options[:rename][column.name.to_sym] ||
                  column.name) : column.name
-              next if column_name == from_primary_key
 
               @definition.column(column_name, column.type,
-                :limit => column.limit, :default => column.default,
-                :precision => column.precision, :scale => column.scale,
-                :null => column.null, collation: column.collation)
+                limit: column.limit, default: column.default,
+                precision: column.precision, scale: column.scale,
+                null: column.null, collation: column.collation,
+                primary_key: column_name == from_primary_key
+              )
             end
             yield @definition if block_given?
           end
@@ -472,9 +431,12 @@ module ActiveRecord
             options[:rename] || {})
         end
 
-        def copy_table_indexes(from, to, rename = {}) #:nodoc:
+        def copy_table_indexes(from, to, rename = {})
           indexes(from).each do |index|
             name = index.name
+            # indexes sqlite creates for internal use start with `sqlite_` and
+            # don't need to be copied
+            next if name.starts_with?("sqlite_")
             if to == "a#{from}"
               name = "t#{name}"
             elsif from == "a#{to}"
@@ -482,7 +444,7 @@ module ActiveRecord
             end
 
             to_column_names = columns(to).map(&:name)
-            columns = index.columns.map {|c| rename[c] || c }.select do |column|
+            columns = index.columns.map { |c| rename[c] || c }.select do |column|
               to_column_names.include?(column)
             end
 
@@ -490,26 +452,27 @@ module ActiveRecord
               # index name can't be the same
               opts = { name: name.gsub(/(^|_)(#{from})_/, "\\1#{to}_"), internal: true }
               opts[:unique] = true if index.unique
+              opts[:where] = index.where if index.where
               add_index(to, columns, opts)
             end
           end
         end
 
-        def copy_table_contents(from, to, columns, rename = {}) #:nodoc:
-          column_mappings = Hash[columns.map {|name| [name, name]}]
+        def copy_table_contents(from, to, columns, rename = {})
+          column_mappings = Hash[columns.map { |name| [name, name] }]
           rename.each { |a| column_mappings[a.last] = a.first }
           from_columns = columns(from).collect(&:name)
-          columns = columns.find_all{|col| from_columns.include?(column_mappings[col])}
+          columns = columns.find_all { |col| from_columns.include?(column_mappings[col]) }
           from_columns_to_copy = columns.map { |col| column_mappings[col] }
-          quoted_columns = columns.map { |col| quote_column_name(col) } * ','
-          quoted_from_columns = from_columns_to_copy.map { |col| quote_column_name(col) } * ','
+          quoted_columns = columns.map { |col| quote_column_name(col) } * ","
+          quoted_from_columns = from_columns_to_copy.map { |col| quote_column_name(col) } * ","
 
           exec_query("INSERT INTO #{quote_table_name(to)} (#{quoted_columns})
                      SELECT #{quoted_from_columns} FROM #{quote_table_name(from)}")
         end
 
         def sqlite_version
-          @sqlite_version ||= SQLite3Adapter::Version.new(select_value('select sqlite_version(*)'))
+          @sqlite_version ||= SQLite3Adapter::Version.new(query_value("SELECT sqlite_version(*)"))
         end
 
         def translate_exception(exception, message)
@@ -520,42 +483,47 @@ module ActiveRecord
           #   column *column_name* is not unique
           when /column(s)? .* (is|are) not unique/, /UNIQUE constraint failed: .*/
             RecordNotUnique.new(message)
+          when /.* may not be NULL/, /NOT NULL constraint failed: .*/
+            NotNullViolation.new(message)
+          when /FOREIGN KEY constraint failed/i
+            InvalidForeignKey.new(message)
           else
             super
           end
         end
 
-      private
         COLLATE_REGEX = /.*\"(\w+)\".*collate\s+\"(\w+)\".*/i.freeze
 
         def table_structure_with_collation(table_name, basic_structure)
           collation_hash = {}
-          sql            = "SELECT sql FROM
-                              (SELECT * FROM sqlite_master UNION ALL
-                               SELECT * FROM sqlite_temp_master)
-                            WHERE type='table' and name='#{ table_name }' \;"
+          sql = <<-SQL
+            SELECT sql FROM
+              (SELECT * FROM sqlite_master UNION ALL
+               SELECT * FROM sqlite_temp_master)
+            WHERE type = 'table' AND name = #{quote(table_name)}
+          SQL
 
           # Result will have following sample string
           # CREATE TABLE "users" ("id" INTEGER PRIMARY KEY AUTOINCREMENT NOT NULL,
           #                       "password_digest" varchar COLLATE "NOCASE");
-          result = exec_query(sql, 'SCHEMA').first
+          result = exec_query(sql, "SCHEMA").first
 
           if result
             # Splitting with left parentheses and picking up last will return all
             # columns separated with comma(,).
-            columns_string = result["sql"].split('(').last
+            columns_string = result["sql"].split("(").last
 
-            columns_string.split(',').each do |column_string|
+            columns_string.split(",").each do |column_string|
               # This regex will match the column name and collation type and will save
               # the value in $1 and $2 respectively.
-              collation_hash[$1] = $2 if (COLLATE_REGEX =~ column_string)
+              collation_hash[$1] = $2 if COLLATE_REGEX =~ column_string
             end
 
             basic_structure.map! do |column|
-              column_name = column['name']
+              column_name = column["name"]
 
               if collation_hash.has_key? column_name
-                column['collation'] = collation_hash[column_name]
+                column["collation"] = collation_hash[column_name]
               end
 
               column
@@ -564,6 +532,26 @@ module ActiveRecord
             basic_structure.to_hash
           end
         end
+
+        def arel_visitor
+          Arel::Visitors::SQLite.new(self)
+        end
+
+        def configure_connection
+          execute("PRAGMA foreign_keys = ON", "SCHEMA")
+        end
+
+        class SQLite3Integer < Type::Integer # :nodoc:
+          private
+            def _limit
+              # INTEGER storage class can be stored 8 bytes value.
+              # See https://www.sqlite.org/datatype3.html#storage_classes_and_datatypes
+              limit || 8
+            end
+        end
+
+        ActiveRecord::Type.register(:integer, SQLite3Integer, adapter: :sqlite3)
     end
+    ActiveSupport.run_load_hooks(:active_record_sqlite3adapter, SQLite3Adapter)
   end
 end
diff --git a/activerecord/lib/active_record/connection_adapters/statement_pool.rb b/activerecord/lib/active_record/connection_adapters/statement_pool.rb
index 9b0ed3e08b..46bd831da7 100644
--- a/activerecord/lib/active_record/connection_adapters/statement_pool.rb
+++ b/activerecord/lib/active_record/connection_adapters/statement_pool.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActiveRecord
   module ConnectionAdapters
     class StatementPool # :nodoc:
@@ -6,7 +8,7 @@ module ActiveRecord
       DEFAULT_STATEMENT_LIMIT = 1000
 
       def initialize(statement_limit = nil)
-        @cache = Hash.new { |h,pid| h[pid] = {} }
+        @cache = Hash.new { |h, pid| h[pid] = {} }
         @statement_limit = statement_limit || DEFAULT_STATEMENT_LIMIT
       end
 
@@ -47,13 +49,13 @@ module ActiveRecord
 
       private
 
-      def cache
-        @cache[Process.pid]
-      end
+        def cache
+          @cache[Process.pid]
+        end
 
-      def dealloc(stmt)
-        raise NotImplementedError
-      end
+        def dealloc(stmt)
+          raise NotImplementedError
+        end
     end
   end
 end
diff --git a/activerecord/lib/active_record/connection_handling.rb b/activerecord/lib/active_record/connection_handling.rb
index 99fdef67d0..88d28dc52a 100644
--- a/activerecord/lib/active_record/connection_handling.rb
+++ b/activerecord/lib/active_record/connection_handling.rb
@@ -1,6 +1,8 @@
+# frozen_string_literal: true
+
 module ActiveRecord
   module ConnectionHandling
-    RAILS_ENV   = -> { (Rails.env if defined?(Rails.env)) || ENV["RAILS_ENV"] || ENV["RACK_ENV"] }
+    RAILS_ENV   = -> { (Rails.env if defined?(Rails.env)) || ENV["RAILS_ENV"].presence || ENV["RACK_ENV"].presence }
     DEFAULT_ENV = -> { RAILS_ENV.call || "default_env" }
 
     # Establishes the connection to the database. Accepts a hash as input where
@@ -73,7 +75,7 @@ module ActiveRecord
       private
         def config
           @raw_config.dup.tap do |cfg|
-            if url = ENV['DATABASE_URL']
+            if url = ENV["DATABASE_URL"]
               cfg[@env] ||= {}
               cfg[@env]["url"] ||= url
             end
@@ -98,14 +100,6 @@ module ActiveRecord
       @connection_specification_name
     end
 
-    def connection_id
-      ActiveRecord::RuntimeRegistry.connection_id ||= Thread.current.object_id
-    end
-
-    def connection_id=(connection_id)
-      ActiveRecord::RuntimeRegistry.connection_id = connection_id
-    end
-
     # Returns the configuration of the associated connection as a hash:
     #
     #  ActiveRecord::Base.connection_config
@@ -117,7 +111,7 @@ module ActiveRecord
     end
 
     def connection_pool
-      connection_handler.retrieve_connection_pool(connection_specification_name) or raise ConnectionNotEstablished
+      connection_handler.retrieve_connection_pool(connection_specification_name) || raise(ConnectionNotEstablished)
     end
 
     def retrieve_connection
@@ -146,6 +140,6 @@ module ActiveRecord
     end
 
     delegate :clear_active_connections!, :clear_reloadable_connections!,
-      :clear_all_connections!, :to => :connection_handler
+      :clear_all_connections!, :flush_idle_connections!, to: :connection_handler
   end
 end
diff --git a/activerecord/lib/active_record/core.rb b/activerecord/lib/active_record/core.rb
index de337b24d6..88810cb328 100644
--- a/activerecord/lib/active_record/core.rb
+++ b/activerecord/lib/active_record/core.rb
@@ -1,7 +1,8 @@
-require 'thread'
-require 'active_support/core_ext/hash/indifferent_access'
-require 'active_support/core_ext/object/duplicable'
-require 'active_support/core_ext/string/filters'
+# frozen_string_literal: true
+
+require "active_support/core_ext/hash/indifferent_access"
+require "active_support/core_ext/string/filters"
+require "concurrent/map"
 
 module ActiveRecord
   module Core
@@ -17,6 +18,13 @@ module ActiveRecord
       mattr_accessor :logger, instance_writer: false
 
       ##
+      # :singleton-method:
+      #
+      # Specifies if the methods calling database queries should be logged below
+      # their relevant queries. Defaults to false.
+      mattr_accessor :verbose_query_logs, instance_writer: false, default: false
+
+      ##
       # Contains the database configuration - as is typically stored in config/database.yml -
       # as a Hash.
       #
@@ -56,8 +64,7 @@ module ActiveRecord
       # :singleton-method:
       # Determines whether to use Time.utc (using :utc) or Time.local (using :local) when pulling
       # dates and times from the database. This is set to :utc by default.
-      mattr_accessor :default_timezone, instance_writer: false
-      self.default_timezone = :utc
+      mattr_accessor :default_timezone, instance_writer: false, default: :utc
 
       ##
       # :singleton-method:
@@ -67,22 +74,27 @@ module ActiveRecord
       # ActiveRecord::Schema file which can be loaded into any database that
       # supports migrations. Use :ruby if you want to have different database
       # adapters for, e.g., your development and test environments.
-      mattr_accessor :schema_format, instance_writer: false
-      self.schema_format = :ruby
+      mattr_accessor :schema_format, instance_writer: false, default: :ruby
 
       ##
       # :singleton-method:
-      # Specifies if an error should be raised on query limit or order being
+      # Specifies if an error should be raised if the query has an order being
       # ignored when doing batch queries. Useful in applications where the
-      # limit or scope being ignored is error-worthy, rather than a warning.
-      mattr_accessor :error_on_ignored_order_or_limit, instance_writer: false
-      self.error_on_ignored_order_or_limit = false
+      # scope being ignored is error-worthy, rather than a warning.
+      mattr_accessor :error_on_ignored_order, instance_writer: false, default: false
+
+      # :singleton-method:
+      # Specify the behavior for unsafe raw query methods. Values are as follows
+      #   deprecated - Warnings are logged when unsafe raw SQL is passed to
+      #                query methods.
+      #   disabled   - Unsafe raw SQL passed to query methods results in
+      #                UnknownAttributeReference exception.
+      mattr_accessor :allow_unsafe_raw_sql, instance_writer: false, default: :deprecated
 
       ##
       # :singleton-method:
       # Specify whether or not to use timestamps for migration versions
-      mattr_accessor :timestamped_migrations, instance_writer: false
-      self.timestamped_migrations = true
+      mattr_accessor :timestamped_migrations, instance_writer: false, default: true
 
       ##
       # :singleton-method:
@@ -90,8 +102,7 @@ module ActiveRecord
       # db:migrate rake task. This is true by default, which is useful for the
       # development environment. This should ideally be false in the production
       # environment where dumping schema is rarely needed.
-      mattr_accessor :dump_schema_after_migration, instance_writer: false
-      self.dump_schema_after_migration = true
+      mattr_accessor :dump_schema_after_migration, instance_writer: false, default: true
 
       ##
       # :singleton-method:
@@ -100,8 +111,7 @@ module ActiveRecord
       # schema_search_path are dumped. Use :all to dump all schemas regardless
       # of schema_search_path, or a string of comma separated schemas for a
       # custom list.
-      mattr_accessor :dump_schemas, instance_writer: false
-      self.dump_schemas = :schema_search_path
+      mattr_accessor :dump_schemas, instance_writer: false, default: :schema_search_path
 
       ##
       # :singleton-method:
@@ -110,7 +120,6 @@ module ActiveRecord
       # be used to identify queries which load thousands of records and
       # potentially cause memory bloat.
       mattr_accessor :warn_on_records_fetched_greater_than, instance_writer: false
-      self.warn_on_records_fetched_greater_than = nil
 
       mattr_accessor :maintain_test_schema, instance_accessor: false
 
@@ -129,14 +138,14 @@ module ActiveRecord
       self.default_connection_handler = ConnectionAdapters::ConnectionHandler.new
     end
 
-    module ClassMethods
+    module ClassMethods # :nodoc:
       def allocate
         define_attribute_methods
         super
       end
 
       def initialize_find_by_cache # :nodoc:
-        @find_by_statement_cache = { true => {}.extend(Mutex_m), false => {}.extend(Mutex_m) }
+        @find_by_statement_cache = { true => Concurrent::Map.new, false => Concurrent::Map.new }
       end
 
       def inherited(child_class) # :nodoc:
@@ -151,41 +160,36 @@ module ActiveRecord
         return super if block_given? ||
                         primary_key.nil? ||
                         scope_attributes? ||
-                        columns_hash.include?(inheritance_column) ||
-                        ids.first.kind_of?(Array)
-
-        id  = ids.first
-        if ActiveRecord::Base === id
-          id = id.id
-          ActiveSupport::Deprecation.warn(<<-MSG.squish)
-            You are passing an instance of ActiveRecord::Base to `find`.
-            Please pass the id of the object by calling `.id`.
-          MSG
-        end
+                        columns_hash.include?(inheritance_column)
+
+        id = ids.first
+
+        return super if StatementCache.unsupported_value?(id)
 
         key = primary_key
 
         statement = cached_find_by_statement(key) { |params|
           where(key => params.bind).limit(1)
         }
-        record = statement.execute([id], self, connection).first
+
+        record = statement.execute([id], connection).first
         unless record
           raise RecordNotFound.new("Couldn't find #{name} with '#{primary_key}'=#{id}",
                                    name, primary_key, id)
         end
         record
-      rescue RangeError
+      rescue ::RangeError
         raise RecordNotFound.new("Couldn't find #{name} with an out of range value for '#{primary_key}'",
                                  name, primary_key)
       end
 
       def find_by(*args) # :nodoc:
-        return super if scope_attributes? || !(Hash === args.first) || reflect_on_all_aggregations.any?
+        return super if scope_attributes? || reflect_on_all_aggregations.any?
 
         hash = args.first
 
-        return super if hash.values.any? { |v|
-          v.nil? || Array === v || Hash === v || Relation === v
+        return super if !(Hash === hash) || hash.values.any? { |v|
+          StatementCache.unsupported_value?(v)
         }
 
         # We can't cache Post.find_by(author: david) ...yet
@@ -200,16 +204,16 @@ module ActiveRecord
           where(wheres).limit(1)
         }
         begin
-          statement.execute(hash.values, self, connection).first
+          statement.execute(hash.values, connection).first
         rescue TypeError
           raise ActiveRecord::StatementInvalid
-        rescue RangeError
+        rescue ::RangeError
           nil
         end
       end
 
       def find_by!(*args) # :nodoc:
-        find_by(*args) or raise RecordNotFound.new("Couldn't find #{name}", name)
+        find_by(*args) || raise(RecordNotFound.new("Couldn't find #{name}", name))
       end
 
       def initialize_generated_modules # :nodoc:
@@ -219,7 +223,9 @@ module ActiveRecord
       def generated_association_methods
         @generated_association_methods ||= begin
           mod = const_set(:GeneratedAssociationMethods, Module.new)
+          private_constant :GeneratedAssociationMethods
           include mod
+
           mod
         end
       end
@@ -233,14 +239,14 @@ module ActiveRecord
         elsif !connected?
           "#{super} (call '#{super}.connection' to establish a connection)"
         elsif table_exists?
-          attr_list = attribute_types.map { |name, type| "#{name}: #{type.type}" } * ', '
+          attr_list = attribute_types.map { |name, type| "#{name}: #{type.type}" } * ", "
           "#{super}(#{attr_list})"
         else
           "#{super}(Table doesn't exist)"
         end
       end
 
-      # Overwrite the default class equality method to provide support for association proxies.
+      # Overwrite the default class equality method to provide support for decorated models.
       def ===(object)
         object.is_a?(self)
       end
@@ -248,22 +254,12 @@ module ActiveRecord
       # Returns an instance of <tt>Arel::Table</tt> loaded with the current table name.
       #
       #   class Post < ActiveRecord::Base
-      #     scope :published_and_commented, -> { published.and(self.arel_table[:comments_count].gt(0)) }
+      #     scope :published_and_commented, -> { published.and(arel_table[:comments_count].gt(0)) }
       #   end
       def arel_table # :nodoc:
         @arel_table ||= Arel::Table.new(table_name, type_caster: type_caster)
       end
 
-      # Returns the Arel engine.
-      def arel_engine # :nodoc:
-        @arel_engine ||=
-          if Base == self || connection_handler.retrieve_connection_pool(connection_specification_name)
-            self
-          else
-            superclass.arel_engine
-          end
-      end
-
       def arel_attribute(name, table = arel_table) # :nodoc:
         name = attribute_alias(name) if attribute_alias?(name)
         table[name]
@@ -279,26 +275,25 @@ module ActiveRecord
 
       private
 
-      def cached_find_by_statement(key, &block) # :nodoc:
-        cache = @find_by_statement_cache[connection.prepared_statements]
-        cache[key] || cache.synchronize {
-          cache[key] ||= StatementCache.create(connection, &block)
-        }
-      end
+        def cached_find_by_statement(key, &block)
+          cache = @find_by_statement_cache[connection.prepared_statements]
+          cache.compute_if_absent(key) { StatementCache.create(connection, &block) }
+        end
 
-      def relation # :nodoc:
-        relation = Relation.create(self, arel_table, predicate_builder)
+        def relation
+          relation = Relation.create(self, arel_table, predicate_builder)
 
-        if finder_needs_type_condition? && !ignore_default_scope?
-          relation.where(type_condition).create_with(inheritance_column.to_sym => sti_name)
-        else
-          relation
+          if finder_needs_type_condition? && !ignore_default_scope?
+            relation.where!(type_condition)
+            relation.create_with!(inheritance_column.to_s => sti_name)
+          else
+            relation
+          end
         end
-      end
 
-      def table_metadata # :nodoc:
-        TableMetadata.new(self, arel_table)
-      end
+        def table_metadata
+          TableMetadata.new(self, arel_table)
+        end
     end
 
     # New objects can be instantiated as either empty (pass no construction parameter) or pre-set with
@@ -310,8 +305,8 @@ module ActiveRecord
     #   # Instantiates a single new object
     #   User.new(first_name: 'Jamie')
     def initialize(attributes = nil)
-      @attributes = self.class._default_attributes.deep_dup
       self.class.define_attribute_methods
+      @attributes = self.class._default_attributes.deep_dup
 
       init_internals
       initialize_internals_callback
@@ -342,10 +337,12 @@ module ActiveRecord
 
       init_internals
 
-      @new_record = coder['new_record']
+      @new_record = coder["new_record"]
 
       self.class.define_attribute_methods
 
+      yield self if block_given?
+
       _run_find_callbacks
       _run_initialize_callbacks
 
@@ -405,8 +402,8 @@ module ActiveRecord
     #   coder # => {"attributes" => {"id" => nil, ... }}
     def encode_with(coder)
       self.class.yaml_encoder.encode(@attributes, coder)
-      coder['new_record'] = new_record?
-      coder['active_record_yaml_version'] = 2
+      coder["new_record"] = new_record?
+      coder["active_record_yaml_version"] = 2
     end
 
     # Returns true if +comparison_object+ is the same exact object, or +comparison_object+
@@ -430,7 +427,7 @@ module ActiveRecord
     #   [ Person.find(1), Person.find(2), Person.find(3) ] & [ Person.find(1), Person.find(4) ] # => [ Person.find(1) ]
     def hash
       if id
-        [self.class, id].hash
+        self.class.hash ^ id.hash
       else
         super
       end
@@ -452,7 +449,7 @@ module ActiveRecord
     # Allows sort on objects
     def <=>(other_object)
       if other_object.is_a?(self.class)
-        self.to_key <=> other_object.to_key
+        to_key <=> other_object.to_key
       else
         super
       end
@@ -478,14 +475,15 @@ module ActiveRecord
       # We check defined?(@attributes) not to issue warnings if the object is
       # allocated but not initialized.
       inspection = if defined?(@attributes) && @attributes
-                     self.class.column_names.collect { |name|
-                       if has_attribute?(name)
-                         "#{name}: #{attribute_for_inspect(name)}"
-                       end
-                     }.compact.join(", ")
-                   else
-                     "not initialized"
-                   end
+        self.class.attribute_names.collect do |name|
+          if has_attribute?(name)
+            "#{name}: #{attribute_for_inspect(name)}"
+          end
+        end.compact.join(", ")
+      else
+        "not initialized"
+      end
+
       "#<#{self.class} #{inspection}>"
     end
 
@@ -496,64 +494,63 @@ module ActiveRecord
       pp.object_address_group(self) do
         if defined?(@attributes) && @attributes
           column_names = self.class.column_names.select { |name| has_attribute?(name) || new_record? }
-          pp.seplist(column_names, proc { pp.text ',' }) do |column_name|
+          pp.seplist(column_names, proc { pp.text "," }) do |column_name|
             column_value = read_attribute(column_name)
-            pp.breakable ' '
+            pp.breakable " "
             pp.group(1) do
               pp.text column_name
-              pp.text ':'
+              pp.text ":"
               pp.breakable
               pp.pp column_value
             end
           end
         else
-          pp.breakable ' '
-          pp.text 'not initialized'
+          pp.breakable " "
+          pp.text "not initialized"
         end
       end
     end
 
     # Returns a hash of the given methods with their names as keys and returned values as values.
     def slice(*methods)
-      Hash[methods.map! { |method| [method, public_send(method)] }].with_indifferent_access
+      Hash[methods.flatten.map! { |method| [method, public_send(method)] }].with_indifferent_access
     end
 
     private
 
-    # Under Ruby 1.9, Array#flatten will call #to_ary (recursively) on each of the elements
-    # of the array, and then rescues from the possible NoMethodError. If those elements are
-    # ActiveRecord::Base's, then this triggers the various method_missing's that we have,
-    # which significantly impacts upon performance.
-    #
-    # So we can avoid the method_missing hit by explicitly defining #to_ary as nil here.
-    #
-    # See also http://tenderlovemaking.com/2011/06/28/til-its-ok-to-return-nil-from-to_ary.html
-    def to_ary # :nodoc:
-      nil
-    end
+      # +Array#flatten+ will call +#to_ary+ (recursively) on each of the elements of
+      # the array, and then rescues from the possible +NoMethodError+. If those elements are
+      # +ActiveRecord::Base+'s, then this triggers the various +method_missing+'s that we have,
+      # which significantly impacts upon performance.
+      #
+      # So we can avoid the +method_missing+ hit by explicitly defining +#to_ary+ as +nil+ here.
+      #
+      # See also https://tenderlovemaking.com/2011/06/28/til-its-ok-to-return-nil-from-to_ary.html
+      def to_ary
+        nil
+      end
 
-    def init_internals
-      @readonly                 = false
-      @destroyed                = false
-      @marked_for_destruction   = false
-      @destroyed_by_association = nil
-      @new_record               = true
-      @txn                      = nil
-      @_start_transaction_state = {}
-      @transaction_state        = nil
-    end
+      def init_internals
+        @readonly                 = false
+        @destroyed                = false
+        @marked_for_destruction   = false
+        @destroyed_by_association = nil
+        @new_record               = true
+        @_start_transaction_state = {}
+        @transaction_state        = nil
+      end
 
-    def initialize_internals_callback
-    end
+      def initialize_internals_callback
+      end
 
-    def thaw
-      if frozen?
-        @attributes = @attributes.dup
+      def thaw
+        if frozen?
+          @attributes = @attributes.dup
+        end
       end
-    end
 
-    def custom_inspect_method_defined?
-      self.class.instance_method(:inspect).owner != ActiveRecord::Base.instance_method(:inspect).owner
-    end
+      def custom_inspect_method_defined?
+        self.class.instance_method(:inspect).owner != ActiveRecord::Base.instance_method(:inspect).owner
+      end
   end
 end
diff --git a/activerecord/lib/active_record/counter_cache.rb b/activerecord/lib/active_record/counter_cache.rb
index 1b6817554d..ee4f818cbf 100644
--- a/activerecord/lib/active_record/counter_cache.rb
+++ b/activerecord/lib/active_record/counter_cache.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActiveRecord
   # = Active Record Counter Cache
   module CounterCache
@@ -12,13 +14,21 @@ module ActiveRecord
       #
       # * +id+ - The id of the object you wish to reset a counter on.
       # * +counters+ - One or more association counters to reset. Association name or counter name can be given.
+      # * <tt>:touch</tt> - Touch timestamp columns when updating.
+      #   Pass +true+ to touch +updated_at+ and/or +updated_on+. Pass a symbol to
+      #   touch that column or an array of symbols to touch just those ones.
       #
       # ==== Examples
       #
-      #   # For Post with id #1 records reset the comments_count
+      #   # For the Post with id #1, reset the comments_count
       #   Post.reset_counters(1, :comments)
-      def reset_counters(id, *counters)
+      #
+      #   # Like above, but also touch the +updated_at+ and/or +updated_on+
+      #   # attributes.
+      #   Post.reset_counters(1, :comments, touch: true)
+      def reset_counters(id, *counters, touch: nil)
         object = find(id)
+
         counters.each do |counter_association|
           has_many_association = _reflect_on_association(counter_association)
           unless has_many_association
@@ -26,7 +36,7 @@ module ActiveRecord
             has_many_association = has_many.find { |association| association.counter_cache_column && association.counter_cache_column.to_sym == counter_association.to_sym }
             counter_association = has_many_association.plural_name if has_many_association
           end
-          raise ArgumentError, "'#{self.name}' has no association called '#{counter_association}'" unless has_many_association
+          raise ArgumentError, "'#{name}' has no association called '#{counter_association}'" unless has_many_association
 
           if has_many_association.is_a? ActiveRecord::Reflection::ThroughReflection
             has_many_association = has_many_association.through_reflection
@@ -37,11 +47,13 @@ module ActiveRecord
           reflection   = child_class._reflections.values.find { |e| e.belongs_to? && e.foreign_key.to_s == foreign_key && e.options[:counter_cache].present? }
           counter_name = reflection.counter_cache_column
 
-          unscoped.where(primary_key => object.id).update_all(
-            counter_name => object.send(counter_association).count(:all)
-          )
+          updates = { counter_name.to_sym => object.send(counter_association).count(:all) }
+          updates.merge!(touch_updates(touch)) if touch
+
+          unscoped.where(primary_key => object.id).update_all(updates)
         end
-        return true
+
+        true
       end
 
       # A generic "counter updater" implementation, intended primarily to be
@@ -55,6 +67,9 @@ module ActiveRecord
       # * +id+ - The id of the object you wish to update a counter on or an array of ids.
       # * +counters+ - A Hash containing the names of the fields
       #   to update as keys and the amount to update the field by as values.
+      # * <tt>:touch</tt> option - Touch timestamp columns when updating.
+      #   Pass +true+ to touch +updated_at+ and/or +updated_on+. Pass a symbol to
+      #   touch that column or an array of symbols to touch just those ones.
       #
       # ==== Examples
       #
@@ -73,14 +88,30 @@ module ActiveRecord
       #   # UPDATE posts
       #   #    SET comment_count = COALESCE(comment_count, 0) + 1
       #   #  WHERE id IN (10, 15)
+      #
+      #   # For the Posts with id of 10 and 15, increment the comment_count by 1
+      #   # and update the updated_at value for each counter.
+      #   Post.update_counters [10, 15], comment_count: 1, touch: true
+      #   # Executes the following SQL:
+      #   # UPDATE posts
+      #   #    SET comment_count = COALESCE(comment_count, 0) + 1,
+      #   #    `updated_at` = '2016-10-13T09:59:23-05:00'
+      #   #  WHERE id IN (10, 15)
       def update_counters(id, counters)
+        touch = counters.delete(:touch)
+
         updates = counters.map do |counter_name, value|
-          operator = value < 0 ? '-' : '+'
+          operator = value < 0 ? "-" : "+"
           quoted_column = connection.quote_column_name(counter_name)
           "#{quoted_column} = COALESCE(#{quoted_column}, 0) #{operator} #{value.abs}"
         end
 
-        unscoped.where(primary_key => id).update_all updates.join(', ')
+        if touch
+          touch_updates = touch_updates(touch)
+          updates << sanitize_sql_for_assignment(touch_updates) unless touch_updates.empty?
+        end
+
+        unscoped.where(primary_key => id).update_all updates.join(", ")
       end
 
       # Increment a numeric field by one, via a direct SQL update.
@@ -94,13 +125,20 @@ module ActiveRecord
       #
       # * +counter_name+ - The name of the field that should be incremented.
       # * +id+ - The id of the object that should be incremented or an array of ids.
+      # * <tt>:touch</tt> - Touch timestamp columns when updating.
+      #   Pass +true+ to touch +updated_at+ and/or +updated_on+. Pass a symbol to
+      #   touch that column or an array of symbols to touch just those ones.
       #
       # ==== Examples
       #
       #   # Increment the posts_count column for the record with an id of 5
       #   DiscussionBoard.increment_counter(:posts_count, 5)
-      def increment_counter(counter_name, id)
-        update_counters(id, counter_name => 1)
+      #
+      #   # Increment the posts_count column for the record with an id of 5
+      #   # and update the updated_at value.
+      #   DiscussionBoard.increment_counter(:posts_count, 5, touch: true)
+      def increment_counter(counter_name, id, touch: nil)
+        update_counters(id, counter_name => 1, touch: touch)
       end
 
       # Decrement a numeric field by one, via a direct SQL update.
@@ -112,14 +150,28 @@ module ActiveRecord
       #
       # * +counter_name+ - The name of the field that should be decremented.
       # * +id+ - The id of the object that should be decremented or an array of ids.
+      # * <tt>:touch</tt> - Touch timestamp columns when updating.
+      #   Pass +true+ to touch +updated_at+ and/or +updated_on+. Pass a symbol to
+      #   touch that column or an array of symbols to touch just those ones.
       #
       # ==== Examples
       #
       #   # Decrement the posts_count column for the record with an id of 5
       #   DiscussionBoard.decrement_counter(:posts_count, 5)
-      def decrement_counter(counter_name, id)
-        update_counters(id, counter_name => -1)
+      #
+      #   # Decrement the posts_count column for the record with an id of 5
+      #   # and update the updated_at value.
+      #   DiscussionBoard.decrement_counter(:posts_count, 5, touch: true)
+      def decrement_counter(counter_name, id, touch: nil)
+        update_counters(id, counter_name => -1, touch: touch)
       end
+
+      private
+        def touch_updates(touch)
+          touch = timestamp_attributes_for_update_in_model if touch == true
+          touch_time = current_time_from_proper_timezone
+          Array(touch).map { |column| [ column, touch_time ] }.to_h
+        end
     end
 
     private
@@ -130,7 +182,6 @@ module ActiveRecord
         each_counter_cached_associations do |association|
           if send(association.reflection.name)
             association.increment_counters
-            @_after_create_counter_called = true
           end
         end
 
@@ -159,6 +210,5 @@ module ActiveRecord
           yield association(name.to_sym) if reflection.belongs_to? && reflection.counter_cache_column
         end
       end
-
   end
 end
diff --git a/activerecord/lib/active_record/define_callbacks.rb b/activerecord/lib/active_record/define_callbacks.rb
new file mode 100644
index 0000000000..87ecd7cec5
--- /dev/null
+++ b/activerecord/lib/active_record/define_callbacks.rb
@@ -0,0 +1,22 @@
+# frozen_string_literal: true
+
+module ActiveRecord
+  # This module exists because ActiveRecord::AttributeMethods::Dirty needs to
+  # define callbacks, but continue to have its version of +save+ be the super
+  # method of ActiveRecord::Callbacks. This will be removed when the removal
+  # of deprecated code removes this need.
+  module DefineCallbacks
+    extend ActiveSupport::Concern
+
+    module ClassMethods # :nodoc:
+      include ActiveModel::Callbacks
+    end
+
+    included do
+      include ActiveModel::Validations::Callbacks
+
+      define_model_callbacks :initialize, :find, :touch, only: :after
+      define_model_callbacks :save, :create, :update, :destroy
+    end
+  end
+end
diff --git a/activerecord/lib/active_record/dynamic_matchers.rb b/activerecord/lib/active_record/dynamic_matchers.rb
index b6dd6814db..3bb8c6f4e3 100644
--- a/activerecord/lib/active_record/dynamic_matchers.rb
+++ b/activerecord/lib/active_record/dynamic_matchers.rb
@@ -1,121 +1,122 @@
+# frozen_string_literal: true
+
 module ActiveRecord
   module DynamicMatchers #:nodoc:
-    def respond_to?(name, include_private = false)
-      if self == Base
-        super
-      else
+    private
+      def respond_to_missing?(name, _)
+        if self == Base
+          super
+        else
+          match = Method.match(self, name)
+          match && match.valid? || super
+        end
+      end
+
+      def method_missing(name, *arguments, &block)
         match = Method.match(self, name)
-        match && match.valid? || super
+
+        if match && match.valid?
+          match.define
+          send(name, *arguments, &block)
+        else
+          super
+        end
       end
-    end
 
-    private
+      class Method
+        @matchers = []
 
-    def method_missing(name, *arguments, &block)
-      match = Method.match(self, name)
+        class << self
+          attr_reader :matchers
 
-      if match && match.valid?
-        match.define
-        send(name, *arguments, &block)
-      else
-        super
-      end
-    end
+          def match(model, name)
+            klass = matchers.find { |k| k.pattern.match?(name) }
+            klass.new(model, name) if klass
+          end
 
-    class Method
-      @matchers = []
+          def pattern
+            @pattern ||= /\A#{prefix}_([_a-zA-Z]\w*)#{suffix}\Z/
+          end
 
-      class << self
-        attr_reader :matchers
+          def prefix
+            raise NotImplementedError
+          end
 
-        def match(model, name)
-          klass = matchers.find { |k| name =~ k.pattern }
-          klass.new(model, name) if klass
+          def suffix
+            ""
+          end
         end
 
-        def pattern
-          @pattern ||= /\A#{prefix}_([_a-zA-Z]\w*)#{suffix}\Z/
-        end
+        attr_reader :model, :name, :attribute_names
 
-        def prefix
-          raise NotImplementedError
+        def initialize(model, name)
+          @model           = model
+          @name            = name.to_s
+          @attribute_names = @name.match(self.class.pattern)[1].split("_and_")
+          @attribute_names.map! { |n| @model.attribute_aliases[n] || n }
         end
 
-        def suffix
-          ''
+        def valid?
+          attribute_names.all? { |name| model.columns_hash[name] || model.reflect_on_aggregation(name.to_sym) }
         end
-      end
-
-      attr_reader :model, :name, :attribute_names
 
-      def initialize(model, name)
-        @model           = model
-        @name            = name.to_s
-        @attribute_names = @name.match(self.class.pattern)[1].split('_and_')
-        @attribute_names.map! { |n| @model.attribute_aliases[n] || n }
-      end
+        def define
+          model.class_eval <<-CODE, __FILE__, __LINE__ + 1
+            def self.#{name}(#{signature})
+              #{body}
+            end
+          CODE
+        end
 
-      def valid?
-        attribute_names.all? { |name| model.columns_hash[name] || model.reflect_on_aggregation(name.to_sym) }
-      end
+        private
 
-      def define
-        model.class_eval <<-CODE, __FILE__, __LINE__ + 1
-          def self.#{name}(#{signature})
-            #{body}
+          def body
+            "#{finder}(#{attributes_hash})"
           end
-        CODE
-      end
-
-      private
-
-      def body
-        "#{finder}(#{attributes_hash})"
-      end
 
-      # The parameters in the signature may have reserved Ruby words, in order
-      # to prevent errors, we start each param name with `_`.
-      def signature
-        attribute_names.map { |name| "_#{name}" }.join(', ')
-      end
+          # The parameters in the signature may have reserved Ruby words, in order
+          # to prevent errors, we start each param name with `_`.
+          def signature
+            attribute_names.map { |name| "_#{name}" }.join(", ")
+          end
 
-      # Given that the parameters starts with `_`, the finder needs to use the
-      # same parameter name.
-      def attributes_hash
-        "{" + attribute_names.map { |name| ":#{name} => _#{name}" }.join(',') + "}"
-      end
+          # Given that the parameters starts with `_`, the finder needs to use the
+          # same parameter name.
+          def attributes_hash
+            "{" + attribute_names.map { |name| ":#{name} => _#{name}" }.join(",") + "}"
+          end
 
-      def finder
-        raise NotImplementedError
+          def finder
+            raise NotImplementedError
+          end
       end
-    end
 
-    class FindBy < Method
-      Method.matchers << self
+      class FindBy < Method
+        Method.matchers << self
 
-      def self.prefix
-        "find_by"
-      end
+        def self.prefix
+          "find_by"
+        end
 
-      def finder
-        "find_by"
+        def finder
+          "find_by"
+        end
       end
-    end
 
-    class FindByBang < Method
-      Method.matchers << self
+      class FindByBang < Method
+        Method.matchers << self
 
-      def self.prefix
-        "find_by"
-      end
+        def self.prefix
+          "find_by"
+        end
 
-      def self.suffix
-        "!"
-      end
+        def self.suffix
+          "!"
+        end
 
-      def finder
-        "find_by!"
+        def finder
+          "find_by!"
+        end
       end
-    end
   end
 end
diff --git a/activerecord/lib/active_record/enum.rb b/activerecord/lib/active_record/enum.rb
index 7be332fb97..1a3e6e4d09 100644
--- a/activerecord/lib/active_record/enum.rb
+++ b/activerecord/lib/active_record/enum.rb
@@ -1,4 +1,6 @@
-require 'active_support/core_ext/object/deep_dup'
+# frozen_string_literal: true
+
+require "active_support/core_ext/object/deep_dup"
 
 module ActiveRecord
   # Declare an enum attribute where the values map to integers in the database,
@@ -95,8 +97,7 @@ module ActiveRecord
 
   module Enum
     def self.extended(base) # :nodoc:
-      base.class_attribute(:defined_enums, instance_writer: false)
-      base.defined_enums = {}
+      base.class_attribute(:defined_enums, instance_writer: false, default: {})
     end
 
     def inherited(base) # :nodoc:
@@ -105,6 +106,8 @@ module ActiveRecord
     end
 
     class EnumType < Type::Value # :nodoc:
+      delegate :type, to: :subtype
+
       def initialize(name, mapping, subtype)
         @name = name
         @mapping = mapping
@@ -138,9 +141,11 @@ module ActiveRecord
         end
       end
 
+      # TODO Change this to private once we've dropped Ruby 2.2 support.
+      # Workaround for Ruby 2.2 "private attribute?" warning.
       protected
 
-      attr_reader :name, :mapping, :subtype
+        attr_reader :name, :mapping, :subtype
     end
 
     def enum(definitions)
@@ -150,22 +155,24 @@ module ActiveRecord
       definitions.each do |name, values|
         # statuses = { }
         enum_values = ActiveSupport::HashWithIndifferentAccess.new
-        name        = name.to_sym
+        name = name.to_s
 
         # def self.statuses() statuses end
-        detect_enum_conflict!(name, name.to_s.pluralize, true)
-        klass.singleton_class.send(:define_method, name.to_s.pluralize) { enum_values }
+        detect_enum_conflict!(name, name.pluralize, true)
+        singleton_class.send(:define_method, name.pluralize) { enum_values }
+        defined_enums[name] = enum_values
 
         detect_enum_conflict!(name, name)
         detect_enum_conflict!(name, "#{name}=")
 
-        decorate_attribute_type(name, :enum) do |subtype|
-          EnumType.new(name, enum_values, subtype)
+        attr = attribute_alias?(name) ? attribute_alias(name) : name
+        decorate_attribute_type(attr, :enum) do |subtype|
+          EnumType.new(attr, enum_values, subtype)
         end
 
         _enum_methods_module.module_eval do
           pairs = values.respond_to?(:each_pair) ? values.each_pair : values.each_with_index
-          pairs.each do |value, i|
+          pairs.each do |label, value|
             if enum_prefix == true
               prefix = "#{name}_"
             elsif enum_prefix
@@ -177,23 +184,23 @@ module ActiveRecord
               suffix = "_#{enum_suffix}"
             end
 
-            value_method_name = "#{prefix}#{value}#{suffix}"
-            enum_values[value] = i
+            value_method_name = "#{prefix}#{label}#{suffix}"
+            enum_values[label] = value
+            label = label.to_s
 
-            # def active?() status == 0 end
+            # def active?() status == "active" end
             klass.send(:detect_enum_conflict!, name, "#{value_method_name}?")
-            define_method("#{value_method_name}?") { self[name] == value.to_s }
+            define_method("#{value_method_name}?") { self[attr] == label }
 
-            # def active!() update! status: :active end
+            # def active!() update!(status: 0) end
             klass.send(:detect_enum_conflict!, name, "#{value_method_name}!")
-            define_method("#{value_method_name}!") { update! name => value }
+            define_method("#{value_method_name}!") { update!(attr => value) }
 
-            # scope :active, -> { where status: 0 }
+            # scope :active, -> { where(status: 0) }
             klass.send(:detect_enum_conflict!, name, value_method_name, true)
-            klass.scope value_method_name, -> { where(name => value) }
+            klass.scope value_method_name, -> { where(attr => value) }
           end
         end
-        defined_enums[name.to_s] = enum_values
       end
     end
 
@@ -213,18 +220,20 @@ module ActiveRecord
 
       def detect_enum_conflict!(enum_name, method_name, klass_method = false)
         if klass_method && dangerous_class_method?(method_name)
-          raise_conflict_error(enum_name, method_name, type: 'class')
+          raise_conflict_error(enum_name, method_name, type: "class")
+        elsif klass_method && method_defined_within?(method_name, Relation)
+          raise_conflict_error(enum_name, method_name, type: "class", source: Relation.name)
         elsif !klass_method && dangerous_attribute_method?(method_name)
           raise_conflict_error(enum_name, method_name)
         elsif !klass_method && method_defined_within?(method_name, _enum_methods_module, Module)
-          raise_conflict_error(enum_name, method_name, source: 'another enum')
+          raise_conflict_error(enum_name, method_name, source: "another enum")
         end
       end
 
-      def raise_conflict_error(enum_name, method_name, type: 'instance', source: 'Active Record')
+      def raise_conflict_error(enum_name, method_name, type: "instance", source: "Active Record")
         raise ArgumentError, ENUM_CONFLICT_MESSAGE % {
           enum: enum_name,
-          klass: self.name,
+          klass: name,
           type: type,
           method: method_name,
           source: source
diff --git a/activerecord/lib/active_record/errors.rb b/activerecord/lib/active_record/errors.rb
index 38e4fbec8b..efcbd44776 100644
--- a/activerecord/lib/active_record/errors.rb
+++ b/activerecord/lib/active_record/errors.rb
@@ -1,5 +1,6 @@
-module ActiveRecord
+# frozen_string_literal: true
 
+module ActiveRecord
   # = Active Record Errors
   #
   # Generic Active Record exception class.
@@ -44,7 +45,7 @@ module ActiveRecord
 
   # Raised when connection to the database could not been established (for example when
   # {ActiveRecord::Base.connection=}[rdoc-ref:ConnectionHandling#connection]
-  # is given a nil object).
+  # is given a +nil+ object).
   class ConnectionNotEstablished < ActiveRecordError
   end
 
@@ -96,20 +97,9 @@ module ActiveRecord
   #
   # Wraps the underlying database error as +cause+.
   class StatementInvalid < ActiveRecordError
-
-    def initialize(message = nil, original_exception = nil)
-      if original_exception
-        ActiveSupport::Deprecation.warn("Passing #original_exception is deprecated and has no effect. " \
-                                        "Exceptions will automatically capture the original exception.", caller)
-      end
-
+    def initialize(message = nil)
       super(message || $!.try(:message))
     end
-
-    def original_exception
-      ActiveSupport::Deprecation.warn("#original_exception is deprecated. Use #cause instead.", caller)
-      cause
-    end
   end
 
   # Defunct wrapper class kept for compatibility.
@@ -117,7 +107,7 @@ module ActiveRecord
   class WrappedDatabaseException < StatementInvalid
   end
 
-  # Raised when a record cannot be inserted because it would violate a uniqueness constraint.
+  # Raised when a record cannot be inserted or updated because it would violate a uniqueness constraint.
   class RecordNotUnique < WrappedDatabaseException
   end
 
@@ -125,10 +115,46 @@ module ActiveRecord
   class InvalidForeignKey < WrappedDatabaseException
   end
 
+  # Raised when a foreign key constraint cannot be added because the column type does not match the referenced column type.
+  class MismatchedForeignKey < StatementInvalid
+    def initialize(adapter = nil, message: nil, table: nil, foreign_key: nil, target_table: nil, primary_key: nil)
+      @adapter = adapter
+      if table
+        msg = <<-EOM.strip_heredoc
+          Column `#{foreign_key}` on table `#{table}` has a type of `#{column_type(table, foreign_key)}`.
+          This does not match column `#{primary_key}` on `#{target_table}`, which has type `#{column_type(target_table, primary_key)}`.
+          To resolve this issue, change the type of the `#{foreign_key}` column on `#{table}` to be :integer. (For example `t.integer #{foreign_key}`).
+        EOM
+      else
+        msg = <<-EOM
+          There is a mismatch between the foreign key and primary key column types.
+          Verify that the foreign key column type and the primary key of the associated table match types.
+        EOM
+      end
+      if message
+        msg << "\nOriginal message: #{message}"
+      end
+      super(msg)
+    end
+
+    private
+      def column_type(table, column)
+        @adapter.columns(table).detect { |c| c.name == column }.sql_type
+      end
+  end
+
+  # Raised when a record cannot be inserted or updated because it would violate a not null constraint.
+  class NotNullViolation < StatementInvalid
+  end
+
   # Raised when a record cannot be inserted or updated because a value too long for a column type.
   class ValueTooLong < StatementInvalid
   end
 
+  # Raised when values that executed are out of range.
+  class RangeError < StatementInvalid
+  end
+
   # Raised when number of bind variables in statement given to +:condition+ key
   # (for example, when using {ActiveRecord::Base.find}[rdoc-ref:FinderMethods#find] method)
   # does not match number of expected values supplied.
@@ -143,7 +169,7 @@ module ActiveRecord
   class NoDatabaseError < StatementInvalid
   end
 
-  # Raised when Postgres returns 'cached plan must not change result type' and
+  # Raised when PostgreSQL returns 'cached plan must not change result type' and
   # we cannot retry gracefully (e.g. inside a transaction)
   class PreparedStatementCacheExpired < StatementInvalid
   end
@@ -166,7 +192,6 @@ module ActiveRecord
         super("Stale object error.")
       end
     end
-
   end
 
   # Raised when association is being configured improperly or user tries to use
@@ -285,18 +310,65 @@ module ActiveRecord
   class TransactionIsolationError < ActiveRecordError
   end
 
-  # TransactionSerializationError will be raised when a transaction is rolled
+  # TransactionRollbackError will be raised when a transaction is rolled
   # back by the database due to a serialization failure or a deadlock.
   #
   # See the following:
   #
-  # * http://www.postgresql.org/docs/current/static/transaction-iso.html
+  # * https://www.postgresql.org/docs/current/static/transaction-iso.html
   # * https://dev.mysql.com/doc/refman/5.7/en/error-messages-server.html#error_er_lock_deadlock
-  class TransactionSerializationError < ActiveRecordError
+  class TransactionRollbackError < StatementInvalid
+  end
+
+  # SerializationFailure will be raised when a transaction is rolled
+  # back by the database due to a serialization failure.
+  class SerializationFailure < TransactionRollbackError
+  end
+
+  # Deadlocked will be raised when a transaction is rolled
+  # back by the database when a deadlock is encountered.
+  class Deadlocked < TransactionRollbackError
   end
 
   # IrreversibleOrderError is raised when a relation's order is too complex for
   # +reverse_order+ to automatically reverse.
   class IrreversibleOrderError < ActiveRecordError
   end
+
+  # LockWaitTimeout will be raised when lock wait timeout exceeded.
+  class LockWaitTimeout < StatementInvalid
+  end
+
+  # StatementTimeout will be raised when statement timeout exceeded.
+  class StatementTimeout < StatementInvalid
+  end
+
+  # QueryCanceled will be raised when canceling statement due to user request.
+  class QueryCanceled < StatementInvalid
+  end
+
+  # UnknownAttributeReference is raised when an unknown and potentially unsafe
+  # value is passed to a query method when allow_unsafe_raw_sql is set to
+  # :disabled. For example, passing a non column name value to a relation's
+  # #order method might cause this exception.
+  #
+  # When working around this exception, caution should be taken to avoid SQL
+  # injection vulnerabilities when passing user-provided values to query
+  # methods. Known-safe values can be passed to query methods by wrapping them
+  # in Arel.sql.
+  #
+  # For example, with allow_unsafe_raw_sql set to :disabled, the following
+  # code would raise this exception:
+  #
+  #   Post.order("length(title)").first
+  #
+  # The desired result can be accomplished by wrapping the known-safe string
+  # in Arel.sql:
+  #
+  #   Post.order(Arel.sql("length(title)")).first
+  #
+  # Again, such a workaround should *not* be used when passing user-provided
+  # values, such as request parameters or model attributes to query methods.
+  class UnknownAttributeReference < ActiveRecordError
+  end
 end
diff --git a/activerecord/lib/active_record/explain.rb b/activerecord/lib/active_record/explain.rb
index 727a9befc1..7ccb938888 100644
--- a/activerecord/lib/active_record/explain.rb
+++ b/activerecord/lib/active_record/explain.rb
@@ -1,5 +1,6 @@
-require 'active_support/lazy_load_hooks'
-require 'active_record/explain_registry'
+# frozen_string_literal: true
+
+require "active_record/explain_registry"
 
 module ActiveRecord
   module Explain
@@ -16,15 +17,14 @@ module ActiveRecord
     # Makes the adapter execute EXPLAIN for the tuples of queries and bindings.
     # Returns a formatted string ready to be logged.
     def exec_explain(queries) # :nodoc:
-      str = queries.map do |sql, bind|
-        [].tap do |msg|
-          msg << "EXPLAIN for: #{sql}"
-          unless bind.empty?
-            bind_msg = bind.map {|col, val| [col.name, val]}.inspect
-            msg.last << " #{bind_msg}"
-          end
-          msg << connection.explain(sql, bind)
-        end.join("\n")
+      str = queries.map do |sql, binds|
+        msg = "EXPLAIN for: #{sql}".dup
+        unless binds.empty?
+          msg << " "
+          msg << binds.map { |attr| render_bind(attr) }.inspect
+        end
+        msg << "\n"
+        msg << connection.explain(sql, binds)
       end.join("\n")
 
       # Overriding inspect to be more human readable, especially in the console.
@@ -34,5 +34,17 @@ module ActiveRecord
 
       str
     end
+
+    private
+
+      def render_bind(attr)
+        value = if attr.type.binary? && attr.value
+          "<#{attr.value_for_database.to_s.bytesize} bytes of binary data>"
+        else
+          connection.type_cast(attr.value_for_database)
+        end
+
+        [attr.name, value]
+      end
   end
 end
diff --git a/activerecord/lib/active_record/explain_registry.rb b/activerecord/lib/active_record/explain_registry.rb
index b652932f9c..7fd078941a 100644
--- a/activerecord/lib/active_record/explain_registry.rb
+++ b/activerecord/lib/active_record/explain_registry.rb
@@ -1,4 +1,6 @@
-require 'active_support/per_thread_registry'
+# frozen_string_literal: true
+
+require "active_support/per_thread_registry"
 
 module ActiveRecord
   # This is a thread locals registry for EXPLAIN. For example
diff --git a/activerecord/lib/active_record/explain_subscriber.rb b/activerecord/lib/active_record/explain_subscriber.rb
index 90bcf5a205..a86217abc0 100644
--- a/activerecord/lib/active_record/explain_subscriber.rb
+++ b/activerecord/lib/active_record/explain_subscriber.rb
@@ -1,5 +1,7 @@
-require 'active_support/notifications'
-require 'active_record/explain_registry'
+# frozen_string_literal: true
+
+require "active_support/notifications"
+require "active_record/explain_registry"
 
 module ActiveRecord
   class ExplainSubscriber # :nodoc:
@@ -18,10 +20,13 @@ module ActiveRecord
     #
     # On the other hand, we want to monitor the performance of our real database
     # queries, not the performance of the access to the query cache.
-    IGNORED_PAYLOADS = %w(SCHEMA EXPLAIN CACHE)
+    IGNORED_PAYLOADS = %w(SCHEMA EXPLAIN)
     EXPLAINED_SQLS = /\A\s*(with|select|update|delete|insert)\b/i
     def ignore_payload?(payload)
-      payload[:exception] || IGNORED_PAYLOADS.include?(payload[:name]) || payload[:sql] !~ EXPLAINED_SQLS
+      payload[:exception] ||
+        payload[:cached] ||
+        IGNORED_PAYLOADS.include?(payload[:name]) ||
+        payload[:sql] !~ EXPLAINED_SQLS
     end
 
     ActiveSupport::Notifications.subscribe("sql.active_record", new)
diff --git a/activerecord/lib/active_record/fixture_set/file.rb b/activerecord/lib/active_record/fixture_set/file.rb
index e4a44244e2..f1ea0e022f 100644
--- a/activerecord/lib/active_record/fixture_set/file.rb
+++ b/activerecord/lib/active_record/fixture_set/file.rb
@@ -1,5 +1,7 @@
-require 'erb'
-require 'yaml'
+# frozen_string_literal: true
+
+require "erb"
+require "yaml"
 
 module ActiveRecord
   class FixtureSet
@@ -24,21 +26,21 @@ module ActiveRecord
       end
 
       def model_class
-        config_row['model_class']
+        config_row["model_class"]
       end
 
       private
         def rows
-          @rows ||= raw_rows.reject { |fixture_name, _| fixture_name == '_fixture' }
+          @rows ||= raw_rows.reject { |fixture_name, _| fixture_name == "_fixture" }
         end
 
         def config_row
           @config_row ||= begin
-            row = raw_rows.find { |fixture_name, _| fixture_name == '_fixture' }
+            row = raw_rows.find { |fixture_name, _| fixture_name == "_fixture" }
             if row
               row.last
             else
-              {'model_class': nil}
+              { 'model_class': nil }
             end
           end
         end
@@ -66,10 +68,13 @@ module ActiveRecord
         # Validate our unmarshalled data.
         def validate(data)
           unless Hash === data || YAML::Omap === data
-            raise Fixture::FormatError, 'fixture is not a hash'
+            raise Fixture::FormatError, "fixture is not a hash: #{@file}"
           end
 
-          raise Fixture::FormatError unless data.all? { |name, row| Hash === row }
+          invalid = data.reject { |_, row| Hash === row }
+          if invalid.any?
+            raise Fixture::FormatError, "fixture key is not a hash: #{@file}, keys: #{invalid.keys.inspect}"
+          end
           data
         end
     end
diff --git a/activerecord/lib/active_record/fixtures.rb b/activerecord/lib/active_record/fixtures.rb
index 51bf12d0bf..86f13d75d5 100644
--- a/activerecord/lib/active_record/fixtures.rb
+++ b/activerecord/lib/active_record/fixtures.rb
@@ -1,11 +1,13 @@
-require 'erb'
-require 'yaml'
-require 'zlib'
-require 'set'
-require 'active_support/dependencies'
-require 'active_support/core_ext/digest/uuid'
-require 'active_record/fixture_set/file'
-require 'active_record/errors'
+# frozen_string_literal: true
+
+require "erb"
+require "yaml"
+require "zlib"
+require "set"
+require "active_support/dependencies"
+require "active_support/core_ext/digest/uuid"
+require "active_record/fixture_set/file"
+require "active_record/errors"
 
 module ActiveRecord
   class FixtureClassNotFound < ActiveRecord::ActiveRecordError #:nodoc:
@@ -70,13 +72,32 @@ module ActiveRecord
   # test. To ensure consistent data, the environment deletes the fixtures before running the load.
   #
   # In addition to being available in the database, the fixture's data may also be accessed by
-  # using a special dynamic method, which has the same name as the model, and accepts the
-  # name of the fixture to instantiate:
+  # using a special dynamic method, which has the same name as the model.
+  #
+  # Passing in a fixture name to this dynamic method returns the fixture matching this name:
   #
-  #   test "find" do
+  #   test "find one" do
   #     assert_equal "Ruby on Rails", web_sites(:rubyonrails).name
   #   end
   #
+  # Passing in multiple fixture names returns all fixtures matching these names:
+  #
+  #   test "find all by name" do
+  #     assert_equal 2, web_sites(:rubyonrails, :google).length
+  #   end
+  #
+  # Passing in no arguments returns all fixtures:
+  #
+  #   test "find all" do
+  #     assert_equal 2, web_sites.length
+  #   end
+  #
+  # Passing in any fixture name that does not exist will raise <tt>StandardError</tt>:
+  #
+  #   test "find by name that does not exist" do
+  #     assert_raise(StandardError) { web_sites(:reddit) }
+  #   end
+  #
   # Alternatively, you may enable auto-instantiation of the fixture data. For instance, take the
   # following tests:
   #
@@ -88,7 +109,7 @@ module ActiveRecord
   #     assert_equal "Ruby on Rails", @rubyonrails.name
   #   end
   #
-  # In order to use these methods to access fixtured data within your testcases, you must specify one of the
+  # In order to use these methods to access fixtured data within your test cases, you must specify one of the
   # following in your ActiveSupport::TestCase-derived class:
   #
   # - to fully enable instantiated fixtures (enable alternate methods #1 and #2 above)
@@ -103,7 +124,7 @@ module ActiveRecord
   #
   # = Dynamic fixtures with ERB
   #
-  # Some times you don't care about the content of the fixtures as much as you care about the volume.
+  # Sometimes you don't care about the content of the fixtures as much as you care about the volume.
   # In these cases, you can mix ERB in with your YAML fixtures to create a bunch of fixtures for load
   # testing, like:
   #
@@ -126,7 +147,7 @@ module ActiveRecord
   # unwanted inter-test dependencies. Methods used by multiple fixtures should be defined in a module
   # that is included in ActiveRecord::FixtureSet.context_class.
   #
-  # - define a helper method in `test_helper.rb`
+  # - define a helper method in <tt>test_helper.rb</tt>
   #     module FixtureFileHelpers
   #       def file_sha(path)
   #         Digest::SHA2.hexdigest(File.read(Rails.root.join('test/fixtures', path)))
@@ -415,9 +436,9 @@ module ActiveRecord
     # possibly in a folder with the same name.
     #++
 
-    MAX_ID = 2 ** 30 - 1
+    MAX_ID = 2**30 - 1
 
-    @@all_cached_fixtures = Hash.new { |h,k| h[k] = {} }
+    @@all_cached_fixtures = Hash.new { |h, k| h[k] = {} }
 
     def self.default_fixture_model_name(fixture_set_name, config = ActiveRecord::Base) # :nodoc:
       config.pluralize_table_names ?
@@ -426,9 +447,9 @@ module ActiveRecord
     end
 
     def self.default_fixture_table_name(fixture_set_name, config = ActiveRecord::Base) # :nodoc:
-       "#{ config.table_name_prefix }"\
-       "#{ fixture_set_name.tr('/', '_') }"\
-       "#{ config.table_name_suffix }".to_sym
+      "#{ config.table_name_prefix }"\
+      "#{ fixture_set_name.tr('/', '_') }"\
+      "#{ config.table_name_suffix }".to_sym
     end
 
     def self.reset_cache
@@ -473,8 +494,7 @@ module ActiveRecord
       end
     end
 
-    cattr_accessor :all_loaded_fixtures
-    self.all_loaded_fixtures = {}
+    cattr_accessor :all_loaded_fixtures, default: {}
 
     class ClassCache
       def initialize(class_names, config)
@@ -494,18 +514,18 @@ module ActiveRecord
 
       private
 
-      def insert_class(class_names, name, klass)
-        # We only want to deal with AR objects.
-        if klass && klass < ActiveRecord::Base
-          class_names[name] = klass
-        else
-          class_names[name] = nil
+        def insert_class(class_names, name, klass)
+          # We only want to deal with AR objects.
+          if klass && klass < ActiveRecord::Base
+            class_names[name] = klass
+          else
+            class_names[name] = nil
+          end
         end
-      end
 
-      def default_fixture_model(fs_name, config)
-        ActiveRecord::FixtureSet.default_fixture_model_name(fs_name, config)
-      end
+        def default_fixture_model(fs_name, config)
+          ActiveRecord::FixtureSet.default_fixture_model_name(fs_name, config)
+        end
     end
 
     def self.create_fixtures(fixtures_directory, fixture_set_names, class_names = {}, config = ActiveRecord::Base)
@@ -535,23 +555,21 @@ module ActiveRecord
 
           update_all_loaded_fixtures fixtures_map
 
-          connection.transaction(:requires_new => true) do
-            deleted_tables = Set.new
+          connection.transaction(requires_new: true) do
+            deleted_tables = Hash.new { |h, k| h[k] = Set.new }
             fixture_sets.each do |fs|
               conn = fs.model_class.respond_to?(:connection) ? fs.model_class.connection : connection
               table_rows = fs.table_rows
 
               table_rows.each_key do |table|
-                unless deleted_tables.include? table
-                  conn.delete "DELETE FROM #{conn.quote_table_name(table)}", 'Fixture Delete'
+                unless deleted_tables[conn].include? table
+                  conn.delete "DELETE FROM #{conn.quote_table_name(table)}", "Fixture Delete"
                 end
-                deleted_tables << table
+                deleted_tables[conn] << table
               end
 
               table_rows.each do |fixture_set_name, rows|
-                rows.each do |row|
-                  conn.insert_fixture(row, fixture_set_name)
-                end
+                conn.insert_fixtures(rows, fixture_set_name)
               end
 
               # Cap primary key sequences to max(pk).
@@ -597,18 +615,18 @@ module ActiveRecord
 
       @fixtures = read_fixture_files(path)
 
-      @connection  = connection
+      @connection = connection
 
-      @table_name = ( model_class.respond_to?(:table_name) ?
+      @table_name = (model_class.respond_to?(:table_name) ?
                       model_class.table_name :
-                      self.class.default_fixture_table_name(name, config) )
+                      self.class.default_fixture_table_name(name, config))
     end
 
     def [](x)
       fixtures[x]
     end
 
-    def []=(k,v)
+    def []=(k, v)
       fixtures[k] = v
     end
 
@@ -626,10 +644,10 @@ module ActiveRecord
       now = config.default_timezone == :utc ? Time.now.utc : Time.now
 
       # allow a standard key to be used for doing defaults in YAML
-      fixtures.delete('DEFAULTS')
+      fixtures.delete("DEFAULTS")
 
       # track any join tables we need to insert later
-      rows = Hash.new { |h,table| h[table] = [] }
+      rows = Hash.new { |h, table| h[table] = [] }
 
       rows[table_name] = fixtures.map do |label, fixture|
         row = fixture.to_hash
@@ -799,7 +817,6 @@ module ActiveRecord
       def yaml_file_path(path)
         "#{path}.yml"
       end
-
   end
 
   class Fixture #:nodoc:
@@ -859,33 +876,13 @@ module ActiveRecord
     end
 
     included do
-      class_attribute :fixture_path, :instance_writer => false
-      class_attribute :fixture_table_names
-      class_attribute :fixture_class_names
-      class_attribute :use_transactional_tests
-      class_attribute :use_transactional_fixtures
-      class_attribute :use_instantiated_fixtures # true, false, or :no_instances
-      class_attribute :pre_loaded_fixtures
-      class_attribute :config
-
-      singleton_class.deprecate 'use_transactional_fixtures=' => 'use use_transactional_tests= instead'
-
-      self.fixture_table_names = []
-      self.use_instantiated_fixtures = false
-      self.pre_loaded_fixtures = false
-      self.config = ActiveRecord::Base
-
-      self.fixture_class_names = {}
-
-      silence_warnings do
-        define_singleton_method :use_transactional_tests do
-          if use_transactional_fixtures.nil?
-            true
-          else
-            use_transactional_fixtures
-          end
-        end
-      end
+      class_attribute :fixture_path, instance_writer: false
+      class_attribute :fixture_table_names, default: []
+      class_attribute :fixture_class_names, default: {}
+      class_attribute :use_transactional_tests, default: true
+      class_attribute :use_instantiated_fixtures, default: false # true, false, or :no_instances
+      class_attribute :pre_loaded_fixtures, default: false
+      class_attribute :config, default: ActiveRecord::Base
     end
 
     module ClassMethods
@@ -898,12 +895,12 @@ module ActiveRecord
       #
       # The keys must be the fixture names, that coincide with the short paths to the fixture files.
       def set_fixture_class(class_names = {})
-        self.fixture_class_names = self.fixture_class_names.merge(class_names.stringify_keys)
+        self.fixture_class_names = fixture_class_names.merge(class_names.stringify_keys)
       end
 
       def fixtures(*fixture_set_names)
         if fixture_set_names.first == :all
-          fixture_set_names = Dir["#{fixture_path}/{**,*}/*.{yml}"]
+          fixture_set_names = Dir["#{fixture_path}/{**,*}/*.{yml}"].uniq
           fixture_set_names.map! { |f| f[(fixture_path.to_s.size + 1)..-5] }
         else
           fixture_set_names = fixture_set_names.flatten.map(&:to_s)
@@ -918,10 +915,12 @@ module ActiveRecord
         methods = Module.new do
           fixture_set_names.each do |fs_name|
             fs_name = fs_name.to_s
-            accessor_name = fs_name.tr('/', '_').to_sym
+            accessor_name = fs_name.tr("/", "_").to_sym
 
             define_method(accessor_name) do |*fixture_names|
               force_reload = fixture_names.pop if fixture_names.last == true || fixture_names.last == :reload
+              return_single_record = fixture_names.size == 1
+              fixture_names = @loaded_fixtures[fs_name].fixtures.keys if fixture_names.empty?
 
               @fixture_cache[fs_name] ||= {}
 
@@ -936,7 +935,7 @@ module ActiveRecord
                 end
               end
 
-              instances.size == 1 ? instances.first : instances
+              return_single_record ? instances.first : instances
             end
             private accessor_name
           end
@@ -962,12 +961,13 @@ module ActiveRecord
 
     def setup_fixtures(config = ActiveRecord::Base)
       if pre_loaded_fixtures && !use_transactional_tests
-        raise RuntimeError, 'pre_loaded_fixtures requires use_transactional_tests'
+        raise RuntimeError, "pre_loaded_fixtures requires use_transactional_tests"
       end
 
       @fixture_cache = {}
       @fixture_connections = []
       @@already_loaded_fixtures ||= {}
+      @connection_subscriber = nil
 
       # Load fixtures once and begin transaction.
       if run_in_transaction?
@@ -977,10 +977,33 @@ module ActiveRecord
           @loaded_fixtures = load_fixtures(config)
           @@already_loaded_fixtures[self.class] = @loaded_fixtures
         end
+
+        # Begin transactions for connections already established
         @fixture_connections = enlist_fixture_connections
         @fixture_connections.each do |connection|
           connection.begin_transaction joinable: false
+          connection.pool.lock_thread = true
         end
+
+        # When connections are established in the future, begin a transaction too
+        @connection_subscriber = ActiveSupport::Notifications.subscribe("!connection.active_record") do |_, _, _, _, payload|
+          spec_name = payload[:spec_name] if payload.key?(:spec_name)
+
+          if spec_name
+            begin
+              connection = ActiveRecord::Base.connection_handler.retrieve_connection(spec_name)
+            rescue ConnectionNotEstablished
+              connection = nil
+            end
+
+            if connection && !@fixture_connections.include?(connection)
+              connection.begin_transaction joinable: false
+              connection.pool.lock_thread = true
+              @fixture_connections << connection
+            end
+          end
+        end
+
       # Load fixtures for every test.
       else
         ActiveRecord::FixtureSet.reset_cache
@@ -995,8 +1018,10 @@ module ActiveRecord
     def teardown_fixtures
       # Rollback changes if a transaction is active.
       if run_in_transaction?
+        ActiveSupport::Notifications.unsubscribe(@connection_subscriber) if @connection_subscriber
         @fixture_connections.each do |connection|
           connection.rollback_transaction if connection.transaction_open?
+          connection.pool.lock_thread = false
         end
         @fixture_connections.clear
       else
@@ -1018,10 +1043,10 @@ module ActiveRecord
 
       def instantiate_fixtures
         if pre_loaded_fixtures
-          raise RuntimeError, 'Load fixtures before instantiating them.' if ActiveRecord::FixtureSet.all_loaded_fixtures.empty?
+          raise RuntimeError, "Load fixtures before instantiating them." if ActiveRecord::FixtureSet.all_loaded_fixtures.empty?
           ActiveRecord::FixtureSet.instantiate_all_loaded_fixtures(self, load_instances?)
         else
-          raise RuntimeError, 'Load fixtures before instantiating them.' if @loaded_fixtures.nil?
+          raise RuntimeError, "Load fixtures before instantiating them." if @loaded_fixtures.nil?
           @loaded_fixtures.each_value do |fixture_set|
             ActiveRecord::FixtureSet.instantiate_fixtures(self, fixture_set, load_instances?)
           end
@@ -1040,6 +1065,10 @@ class ActiveRecord::FixtureSet::RenderContext # :nodoc:
       def get_binding
         binding()
       end
+
+      def binary(path)
+        %(!!binary "#{Base64.strict_encode64(File.read(path))}")
+      end
     end
   end
 end
diff --git a/activerecord/lib/active_record/gem_version.rb b/activerecord/lib/active_record/gem_version.rb
index f33456a744..7e47dac016 100644
--- a/activerecord/lib/active_record/gem_version.rb
+++ b/activerecord/lib/active_record/gem_version.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActiveRecord
   # Returns the version of the currently loaded Active Record as a <tt>Gem::Version</tt>
   def self.gem_version
@@ -6,9 +8,9 @@ module ActiveRecord
 
   module VERSION
     MAJOR = 5
-    MINOR = 1
+    MINOR = 2
     TINY  = 0
-    PRE   = "alpha"
+    PRE   = "beta2"
 
     STRING = [MAJOR, MINOR, TINY, PRE].compact.join(".")
   end
diff --git a/activerecord/lib/active_record/inheritance.rb b/activerecord/lib/active_record/inheritance.rb
index 899683ee4f..f3fe610c09 100644
--- a/activerecord/lib/active_record/inheritance.rb
+++ b/activerecord/lib/active_record/inheritance.rb
@@ -1,4 +1,6 @@
-require 'active_support/core_ext/hash/indifferent_access'
+# frozen_string_literal: true
+
+require "active_support/core_ext/hash/indifferent_access"
 
 module ActiveRecord
   # == Single table inheritance
@@ -19,7 +21,7 @@ module ActiveRecord
   # Be aware that because the type column is an attribute on the record every new
   # subclass will instantly be marked as dirty and the type column will be included
   # in the list of changed attributes on the record. This is different from non
-  # STI classes:
+  # Single Table Inheritance(STI) classes:
   #
   #   Company.new.changed? # => false
   #   Firm.new.changed?    # => true
@@ -30,29 +32,28 @@ module ActiveRecord
   # for differentiating between them or reloading the right type with find.
   #
   # Note, all the attributes for all the cases are kept in the same table. Read more:
-  # http://www.martinfowler.com/eaaCatalog/singleTableInheritance.html
+  # https://www.martinfowler.com/eaaCatalog/singleTableInheritance.html
   #
   module Inheritance
     extend ActiveSupport::Concern
 
     included do
       # Determines whether to store the full constant name including namespace when using STI.
-      class_attribute :store_full_sti_class, instance_writer: false
-      self.store_full_sti_class = true
+      # This is true, by default.
+      class_attribute :store_full_sti_class, instance_writer: false, default: true
     end
 
     module ClassMethods
       # Determines if one of the attributes passed in is the inheritance column,
       # and if the inheritance column is attr accessible, it initializes an
       # instance of the given subclass instead of the base class.
-      def new(*args, &block)
+      def new(attributes = nil, &block)
         if abstract_class? || self == Base
           raise NotImplementedError, "#{self} is an abstract class and cannot be instantiated."
         end
 
-        attrs = args.first
         if has_attribute?(inheritance_column)
-          subclass = subclass_from_attributes(attrs)
+          subclass = subclass_from_attributes(attributes)
 
           if subclass.nil? && base_class == self
             subclass = subclass_from_attributes(column_defaults)
@@ -60,7 +61,7 @@ module ActiveRecord
         end
 
         if subclass && subclass != self
-          subclass.new(*args, &block)
+          subclass.new(attributes, &block)
         else
           super
         end
@@ -129,87 +130,100 @@ module ActiveRecord
         store_full_sti_class ? name : name.demodulize
       end
 
+      def inherited(subclass)
+        subclass.instance_variable_set(:@_type_candidates_cache, Concurrent::Map.new)
+        super
+      end
+
       protected
 
-      # Returns the class type of the record using the current module as a prefix. So descendants of
-      # MyApp::Business::Account would appear as MyApp::Business::AccountSubclass.
-      def compute_type(type_name)
-        if type_name.match(/^::/)
-          # If the type is prefixed with a scope operator then we assume that
-          # the type_name is an absolute reference.
-          ActiveSupport::Dependencies.constantize(type_name)
-        else
-          # Build a list of candidates to search for
-          candidates = []
-          name.scan(/::|$/) { candidates.unshift "#{$`}::#{type_name}" }
-          candidates << type_name
-
-          candidates.each do |candidate|
-            constant = ActiveSupport::Dependencies.safe_constantize(candidate)
-            return constant if candidate == constant.to_s
+        # Returns the class type of the record using the current module as a prefix. So descendants of
+        # MyApp::Business::Account would appear as MyApp::Business::AccountSubclass.
+        def compute_type(type_name)
+          if type_name.start_with?("::".freeze)
+            # If the type is prefixed with a scope operator then we assume that
+            # the type_name is an absolute reference.
+            ActiveSupport::Dependencies.constantize(type_name)
+          else
+            type_candidate = @_type_candidates_cache[type_name]
+            if type_candidate && type_constant = ActiveSupport::Dependencies.safe_constantize(type_candidate)
+              return type_constant
+            end
+
+            # Build a list of candidates to search for
+            candidates = []
+            name.scan(/::|$/) { candidates.unshift "#{$`}::#{type_name}" }
+            candidates << type_name
+
+            candidates.each do |candidate|
+              constant = ActiveSupport::Dependencies.safe_constantize(candidate)
+              if candidate == constant.to_s
+                @_type_candidates_cache[type_name] = candidate
+                return constant
+              end
+            end
+
+            raise NameError.new("uninitialized constant #{candidates.first}", candidates.first)
           end
-
-          raise NameError.new("uninitialized constant #{candidates.first}", candidates.first)
         end
-      end
 
       private
 
-      # Called by +instantiate+ to decide which class to use for a new
-      # record instance. For single-table inheritance, we check the record
-      # for a +type+ column and return the corresponding class.
-      def discriminate_class_for_record(record)
-        if using_single_table_inheritance?(record)
-          find_sti_class(record[inheritance_column])
-        else
-          super
+        # Called by +instantiate+ to decide which class to use for a new
+        # record instance. For single-table inheritance, we check the record
+        # for a +type+ column and return the corresponding class.
+        def discriminate_class_for_record(record)
+          if using_single_table_inheritance?(record)
+            find_sti_class(record[inheritance_column])
+          else
+            super
+          end
         end
-      end
 
-      def using_single_table_inheritance?(record)
-        record[inheritance_column].present? && has_attribute?(inheritance_column)
-      end
+        def using_single_table_inheritance?(record)
+          record[inheritance_column].present? && has_attribute?(inheritance_column)
+        end
 
-      def find_sti_class(type_name)
-        type_name = base_class.type_for_attribute(inheritance_column).cast(type_name)
-        subclass = begin
-          if store_full_sti_class
-            ActiveSupport::Dependencies.constantize(type_name)
-          else
-            compute_type(type_name)
+        def find_sti_class(type_name)
+          type_name = base_class.type_for_attribute(inheritance_column).cast(type_name)
+          subclass = begin
+            if store_full_sti_class
+              ActiveSupport::Dependencies.constantize(type_name)
+            else
+              compute_type(type_name)
+            end
+          rescue NameError
+            raise SubclassNotFound,
+              "The single-table inheritance mechanism failed to locate the subclass: '#{type_name}'. " \
+              "This error is raised because the column '#{inheritance_column}' is reserved for storing the class in case of inheritance. " \
+              "Please rename this column if you didn't intend it to be used for storing the inheritance class " \
+              "or overwrite #{name}.inheritance_column to use another column for that information."
           end
-        rescue NameError
-          raise SubclassNotFound,
-            "The single-table inheritance mechanism failed to locate the subclass: '#{type_name}'. " \
-            "This error is raised because the column '#{inheritance_column}' is reserved for storing the class in case of inheritance. " \
-            "Please rename this column if you didn't intend it to be used for storing the inheritance class " \
-            "or overwrite #{name}.inheritance_column to use another column for that information."
-        end
-        unless subclass == self || descendants.include?(subclass)
-          raise SubclassNotFound, "Invalid single-table inheritance type: #{subclass.name} is not a subclass of #{name}"
+          unless subclass == self || descendants.include?(subclass)
+            raise SubclassNotFound, "Invalid single-table inheritance type: #{subclass.name} is not a subclass of #{name}"
+          end
+          subclass
         end
-        subclass
-      end
 
-      def type_condition(table = arel_table)
-        sti_column = arel_attribute(inheritance_column, table)
-        sti_names  = ([self] + descendants).map(&:sti_name)
+        def type_condition(table = arel_table)
+          sti_column = arel_attribute(inheritance_column, table)
+          sti_names  = ([self] + descendants).map(&:sti_name)
 
-        sti_column.in(sti_names)
-      end
+          sti_column.in(sti_names)
+        end
 
-      # Detect the subclass from the inheritance column of attrs. If the inheritance column value
-      # is not self or a valid subclass, raises ActiveRecord::SubclassNotFound
-      def subclass_from_attributes(attrs)
-        attrs = attrs.to_h if attrs.respond_to?(:permitted?)
-        if attrs.is_a?(Hash)
-          subclass_name = attrs.with_indifferent_access[inheritance_column]
+        # Detect the subclass from the inheritance column of attrs. If the inheritance column value
+        # is not self or a valid subclass, raises ActiveRecord::SubclassNotFound
+        def subclass_from_attributes(attrs)
+          attrs = attrs.to_h if attrs.respond_to?(:permitted?)
+          if attrs.is_a?(Hash)
+            subclass_name = attrs[inheritance_column] || attrs[inheritance_column.to_sym]
 
-          if subclass_name.present?
-            find_sti_class(subclass_name)
+            if subclass_name.present?
+              find_sti_class(subclass_name)
+            end
           end
         end
-      end
     end
 
     def initialize_dup(other)
@@ -219,21 +233,21 @@ module ActiveRecord
 
     private
 
-    def initialize_internals_callback
-      super
-      ensure_proper_type
-    end
+      def initialize_internals_callback
+        super
+        ensure_proper_type
+      end
 
-    # Sets the attribute used for single table inheritance to this class name if this is not the
-    # ActiveRecord::Base descendant.
-    # Considering the hierarchy Reply < Message < ActiveRecord::Base, this makes it possible to
-    # do Reply.new without having to set <tt>Reply[Reply.inheritance_column] = "Reply"</tt> yourself.
-    # No such attribute would be set for objects of the Message class in that example.
-    def ensure_proper_type
-      klass = self.class
-      if klass.finder_needs_type_condition?
-        write_attribute(klass.inheritance_column, klass.sti_name)
+      # Sets the attribute used for single table inheritance to this class name if this is not the
+      # ActiveRecord::Base descendant.
+      # Considering the hierarchy Reply < Message < ActiveRecord::Base, this makes it possible to
+      # do Reply.new without having to set <tt>Reply[Reply.inheritance_column] = "Reply"</tt> yourself.
+      # No such attribute would be set for objects of the Message class in that example.
+      def ensure_proper_type
+        klass = self.class
+        if klass.finder_needs_type_condition?
+          _write_attribute(klass.inheritance_column, klass.sti_name)
+        end
       end
-    end
   end
 end
diff --git a/activerecord/lib/active_record/integration.rb b/activerecord/lib/active_record/integration.rb
index 466c8509a4..6cf26a9792 100644
--- a/activerecord/lib/active_record/integration.rb
+++ b/activerecord/lib/active_record/integration.rb
@@ -1,4 +1,6 @@
-require 'active_support/core_ext/string/filters'
+# frozen_string_literal: true
+
+require "active_support/core_ext/string/filters"
 
 module ActiveRecord
   module Integration
@@ -7,17 +9,24 @@ module ActiveRecord
     included do
       ##
       # :singleton-method:
-      # Indicates the format used to generate the timestamp in the cache key.
-      # Accepts any of the symbols in <tt>Time::DATE_FORMATS</tt>.
+      # Indicates the format used to generate the timestamp in the cache key, if
+      # versioning is off. Accepts any of the symbols in <tt>Time::DATE_FORMATS</tt>.
       #
       # This is +:usec+, by default.
-      class_attribute :cache_timestamp_format, :instance_writer => false
-      self.cache_timestamp_format = :usec
+      class_attribute :cache_timestamp_format, instance_writer: false, default: :usec
+
+      ##
+      # :singleton-method:
+      # Indicates whether to use a stable #cache_key method that is accompanied
+      # by a changing version in the #cache_version method.
+      #
+      # This is +false+, by default until Rails 6.0.
+      class_attribute :cache_versioning, instance_writer: false, default: false
     end
 
-    # Returns a String, which Action Pack uses for constructing a URL to this
-    # object. The default implementation returns this record's id as a String,
-    # or nil if this record's unsaved.
+    # Returns a +String+, which Action Pack uses for constructing a URL to this
+    # object. The default implementation returns this record's id as a +String+,
+    # or +nil+ if this record's unsaved.
     #
     # For example, suppose that you have a User model, and that you have a
     # <tt>resources :users</tt> route. Normally, +user_path+ will
@@ -42,29 +51,62 @@ module ActiveRecord
       id && id.to_s # Be sure to stringify the id for routes
     end
 
-    # Returns a cache key that can be used to identify this record.
+    # Returns a stable cache key that can be used to identify this record.
     #
     #   Product.new.cache_key     # => "products/new"
-    #   Product.find(5).cache_key # => "products/5" (updated_at not available)
-    #   Person.find(5).cache_key  # => "people/5-20071224150000" (updated_at available)
+    #   Product.find(5).cache_key # => "products/5"
     #
-    # You can also pass a list of named timestamps, and the newest in the list will be
-    # used to generate the key:
+    # If ActiveRecord::Base.cache_versioning is turned off, as it was in Rails 5.1 and earlier,
+    # the cache key will also include a version.
     #
-    #   Person.find(5).cache_key(:updated_at, :last_reviewed_at)
+    #   Product.cache_versioning = false
+    #   Person.find(5).cache_key  # => "people/5-20071224150000" (updated_at available)
     def cache_key(*timestamp_names)
-      case
-      when new_record?
+      if new_record?
         "#{model_name.cache_key}/new"
-      when timestamp_names.any?
-        timestamp = max_updated_column_timestamp(timestamp_names)
-        timestamp = timestamp.utc.to_s(cache_timestamp_format)
-        "#{model_name.cache_key}/#{id}-#{timestamp}"
-      when timestamp = max_updated_column_timestamp
-        timestamp = timestamp.utc.to_s(cache_timestamp_format)
-        "#{model_name.cache_key}/#{id}-#{timestamp}"
       else
-        "#{model_name.cache_key}/#{id}"
+        if cache_version && timestamp_names.none?
+          "#{model_name.cache_key}/#{id}"
+        else
+          timestamp = if timestamp_names.any?
+            ActiveSupport::Deprecation.warn(<<-MSG.squish)
+              Specifying a timestamp name for #cache_key has been deprecated in favor of
+              the explicit #cache_version method that can be overwritten.
+            MSG
+
+            max_updated_column_timestamp(timestamp_names)
+          else
+            max_updated_column_timestamp
+          end
+
+          if timestamp
+            timestamp = timestamp.utc.to_s(cache_timestamp_format)
+            "#{model_name.cache_key}/#{id}-#{timestamp}"
+          else
+            "#{model_name.cache_key}/#{id}"
+          end
+        end
+      end
+    end
+
+    # Returns a cache version that can be used together with the cache key to form
+    # a recyclable caching scheme. By default, the #updated_at column is used for the
+    # cache_version, but this method can be overwritten to return something else.
+    #
+    # Note, this method will return nil if ActiveRecord::Base.cache_versioning is set to
+    # +false+ (which it is by default until Rails 6.0).
+    def cache_version
+      if cache_versioning && timestamp = try(:updated_at)
+        timestamp.utc.to_s(:usec)
+      end
+    end
+
+    # Returns a cache key along with the version.
+    def cache_key_with_version
+      if version = cache_version
+        "#{cache_key}-#{version}"
+      else
+        cache_key
       end
     end
 
@@ -86,7 +128,7 @@ module ActiveRecord
       #
       #   user = User.find_by(name: 'David Heinemeier Hansson')
       #   user.id         # => 125
-      #   user_path(user) # => "/users/125-david"
+      #   user_path(user) # => "/users/125-david-heinemeier"
       #
       # Because the generated param begins with the record's +id+, it is
       # suitable for passing to +find+. In a controller, for example:
@@ -100,7 +142,7 @@ module ActiveRecord
           define_method :to_param do
             if (default = super()) &&
                  (result = send(method_name).to_s).present? &&
-                   (param = result.squish.truncate(20, separator: /\s/, omission: nil).parameterize).present?
+                   (param = result.squish.parameterize.truncate(20, separator: /-/, omission: "")).present?
               "#{default}-#{param}"
             else
               default
diff --git a/activerecord/lib/active_record/internal_metadata.rb b/activerecord/lib/active_record/internal_metadata.rb
index 17a5dc1d1b..5a65edf27e 100644
--- a/activerecord/lib/active_record/internal_metadata.rb
+++ b/activerecord/lib/active_record/internal_metadata.rb
@@ -1,5 +1,7 @@
-require 'active_record/scoping/default'
-require 'active_record/scoping/named'
+# frozen_string_literal: true
+
+require "active_record/scoping/default"
+require "active_record/scoping/named"
 
 module ActiveRecord
   # This class is used to create a table that keeps track of values and keys such
@@ -14,10 +16,6 @@ module ActiveRecord
         "#{table_name_prefix}#{ActiveRecord::Base.internal_metadata_table_name}#{table_name_suffix}"
       end
 
-      def original_table_name
-        "#{table_name_prefix}active_record_internal_metadatas#{table_name_suffix}"
-      end
-
       def []=(key, value)
         find_or_initialize_by(key: key).update_attributes!(value: value)
       end
@@ -27,20 +25,11 @@ module ActiveRecord
       end
 
       def table_exists?
-        ActiveSupport::Deprecation.silence { connection.table_exists?(table_name) }
-      end
-
-      def original_table_exists?
-        # This method will be removed in Rails 5.1
-        # Since it is only necessary when `active_record_internal_metadatas` could exist
-        ActiveSupport::Deprecation.silence { connection.table_exists?(original_table_name) }
+        connection.table_exists?(table_name)
       end
 
       # Creates an internal metadata table with columns +key+ and +value+
       def create_table
-        if original_table_exists?
-          connection.rename_table(original_table_name, table_name)
-        end
         unless table_exists?
           key_options = connection.internal_string_options_for_primary_key
 
diff --git a/activerecord/lib/active_record/legacy_yaml_adapter.rb b/activerecord/lib/active_record/legacy_yaml_adapter.rb
index c7683f68c7..ffa095dd94 100644
--- a/activerecord/lib/active_record/legacy_yaml_adapter.rb
+++ b/activerecord/lib/active_record/legacy_yaml_adapter.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActiveRecord
   module LegacyYamlAdapter
     def self.convert(klass, coder)
@@ -6,7 +8,7 @@ module ActiveRecord
       case coder["active_record_yaml_version"]
       when 1, 2 then coder
       else
-        if coder["attributes"].is_a?(AttributeSet)
+        if coder["attributes"].is_a?(ActiveModel::AttributeSet)
           Rails420.convert(klass, coder)
         else
           Rails41.convert(klass, coder)
diff --git a/activerecord/lib/active_record/locking/optimistic.rb b/activerecord/lib/active_record/locking/optimistic.rb
index 67b8efac66..e1e24e2814 100644
--- a/activerecord/lib/active_record/locking/optimistic.rb
+++ b/activerecord/lib/active_record/locking/optimistic.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActiveRecord
   module Locking
     # == What is Optimistic Locking
@@ -51,8 +53,7 @@ module ActiveRecord
       extend ActiveSupport::Concern
 
       included do
-        class_attribute :lock_optimistically, instance_writer: false
-        self.lock_optimistically = true
+        class_attribute :lock_optimistically, instance_writer: false, default: true
       end
 
       def locking_enabled? #:nodoc:
@@ -60,13 +61,14 @@ module ActiveRecord
       end
 
       private
+
         def increment_lock
           lock_col = self.class.locking_column
-          previous_lock_value = send(lock_col).to_i
-          send(lock_col + '=', previous_lock_value + 1)
+          previous_lock_value = send(lock_col)
+          send("#{lock_col}=", previous_lock_value + 1)
         end
 
-        def _create_record(attribute_names = self.attribute_names, *) # :nodoc:
+        def _create_record(attribute_names = self.attribute_names, *)
           if locking_enabled?
             # We always want to persist the locking version, even if we don't detect
             # a change from the default, since the database might have no default
@@ -75,23 +77,24 @@ module ActiveRecord
           super
         end
 
-        def _update_record(attribute_names = self.attribute_names) #:nodoc:
+        def _update_record(attribute_names = self.attribute_names)
           return super unless locking_enabled?
           return 0 if attribute_names.empty?
 
-          lock_col = self.class.locking_column
-          previous_lock_value = send(lock_col).to_i
-          increment_lock
+          begin
+            lock_col = self.class.locking_column
 
-          attribute_names += [lock_col]
-          attribute_names.uniq!
+            previous_lock_value = read_attribute_before_type_cast(lock_col)
+
+            increment_lock
+
+            attribute_names.push(lock_col)
 
-          begin
             relation = self.class.unscoped
 
             affected_rows = relation.where(
               self.class.primary_key => id,
-              lock_col => previous_lock_value,
+              lock_col => previous_lock_value
             ).update_all(
               attributes_for_update(attribute_names).map do |name|
                 [name, _read_attribute(name)]
@@ -104,9 +107,10 @@ module ActiveRecord
 
             affected_rows
 
-          # If something went wrong, revert the version.
+          # If something went wrong, revert the locking_column value.
           rescue Exception
-            send(lock_col + '=', previous_lock_value)
+            send("#{lock_col}=", previous_lock_value.to_i)
+
             raise
           end
         end
@@ -126,65 +130,64 @@ module ActiveRecord
 
           if locking_enabled?
             locking_column = self.class.locking_column
-            relation = relation.where(locking_column => _read_attribute(locking_column))
+            relation = relation.where(locking_column => read_attribute_before_type_cast(locking_column))
           end
 
           relation
         end
 
-      module ClassMethods
-        DEFAULT_LOCKING_COLUMN = 'lock_version'
+        module ClassMethods
+          DEFAULT_LOCKING_COLUMN = "lock_version"
 
-        # Returns true if the +lock_optimistically+ flag is set to true
-        # (which it is, by default) and the table includes the
-        # +locking_column+ column (defaults to +lock_version+).
-        def locking_enabled?
-          lock_optimistically && columns_hash[locking_column]
-        end
+          # Returns true if the +lock_optimistically+ flag is set to true
+          # (which it is, by default) and the table includes the
+          # +locking_column+ column (defaults to +lock_version+).
+          def locking_enabled?
+            lock_optimistically && columns_hash[locking_column]
+          end
 
-        # Set the column to use for optimistic locking. Defaults to +lock_version+.
-        def locking_column=(value)
-          reload_schema_from_cache
-          @locking_column = value.to_s
-        end
+          # Set the column to use for optimistic locking. Defaults to +lock_version+.
+          def locking_column=(value)
+            reload_schema_from_cache
+            @locking_column = value.to_s
+          end
 
-        # The version column used for optimistic locking. Defaults to +lock_version+.
-        def locking_column
-          @locking_column = DEFAULT_LOCKING_COLUMN unless defined?(@locking_column)
-          @locking_column
-        end
+          # The version column used for optimistic locking. Defaults to +lock_version+.
+          def locking_column
+            @locking_column = DEFAULT_LOCKING_COLUMN unless defined?(@locking_column)
+            @locking_column
+          end
 
-        # Reset the column used for optimistic locking back to the +lock_version+ default.
-        def reset_locking_column
-          self.locking_column = DEFAULT_LOCKING_COLUMN
-        end
+          # Reset the column used for optimistic locking back to the +lock_version+ default.
+          def reset_locking_column
+            self.locking_column = DEFAULT_LOCKING_COLUMN
+          end
 
-        # Make sure the lock version column gets updated when counters are
-        # updated.
-        def update_counters(id, counters)
-          counters = counters.merge(locking_column => 1) if locking_enabled?
-          super
-        end
+          # Make sure the lock version column gets updated when counters are
+          # updated.
+          def update_counters(id, counters)
+            counters = counters.merge(locking_column => 1) if locking_enabled?
+            super
+          end
 
-        private
-
-        # We need to apply this decorator here, rather than on module inclusion. The closure
-        # created by the matcher would otherwise evaluate for `ActiveRecord::Base`, not the
-        # sub class being decorated. As such, changes to `lock_optimistically`, or
-        # `locking_column` would not be picked up.
-        def inherited(subclass)
-          subclass.class_eval do
-            is_lock_column = ->(name, _) { lock_optimistically && name == locking_column }
-            decorate_matching_attribute_types(is_lock_column, :_optimistic_locking) do |type|
-              LockingType.new(type)
+          private
+
+            # We need to apply this decorator here, rather than on module inclusion. The closure
+            # created by the matcher would otherwise evaluate for `ActiveRecord::Base`, not the
+            # sub class being decorated. As such, changes to `lock_optimistically`, or
+            # `locking_column` would not be picked up.
+            def inherited(subclass)
+              subclass.class_eval do
+                is_lock_column = ->(name, _) { lock_optimistically && name == locking_column }
+                decorate_matching_attribute_types(is_lock_column, :_optimistic_locking) do |type|
+                  LockingType.new(type)
+                end
+              end
+              super
             end
-          end
-          super
         end
-      end
     end
 
-
     # In de/serialize we change `nil` to 0, so that we can allow passing
     # `nil` values to `lock_version`, and not result in `ActiveRecord::StaleObjectError`
     # during update record.
@@ -198,11 +201,11 @@ module ActiveRecord
       end
 
       def init_with(coder)
-        __setobj__(coder['subtype'])
+        __setobj__(coder["subtype"])
       end
 
       def encode_with(coder)
-        coder['subtype'] = __getobj__
+        coder["subtype"] = __getobj__
       end
     end
   end
diff --git a/activerecord/lib/active_record/locking/pessimistic.rb b/activerecord/lib/active_record/locking/pessimistic.rb
index 8ecdf76b72..bb85c47e06 100644
--- a/activerecord/lib/active_record/locking/pessimistic.rb
+++ b/activerecord/lib/active_record/locking/pessimistic.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActiveRecord
   module Locking
     # Locking::Pessimistic provides support for row-level locking using
@@ -51,15 +53,25 @@ module ActiveRecord
     #   end
     #
     # Database-specific information on row locking:
-    #   MySQL: http://dev.mysql.com/doc/refman/5.7/en/innodb-locking-reads.html
-    #   PostgreSQL: http://www.postgresql.org/docs/current/interactive/sql-select.html#SQL-FOR-UPDATE-SHARE
+    #   MySQL: https://dev.mysql.com/doc/refman/5.7/en/innodb-locking-reads.html
+    #   PostgreSQL: https://www.postgresql.org/docs/current/interactive/sql-select.html#SQL-FOR-UPDATE-SHARE
     module Pessimistic
       # Obtain a row lock on this record. Reloads the record to obtain the requested
       # lock. Pass an SQL locking clause to append the end of the SELECT statement
       # or pass true for "FOR UPDATE" (the default, an exclusive row lock). Returns
       # the locked record.
       def lock!(lock = true)
-        reload(:lock => lock) if persisted?
+        if persisted?
+          if changed?
+            raise(<<-MSG.squish)
+              Locking a record with unpersisted changes is not supported. Use
+              `save` to persist the changes, or `reload` to discard them
+              explicitly.
+            MSG
+          end
+
+          reload(lock: lock)
+        end
         self
       end
 
diff --git a/activerecord/lib/active_record/log_subscriber.rb b/activerecord/lib/active_record/log_subscriber.rb
index 8e32af1c49..9234029c22 100644
--- a/activerecord/lib/active_record/log_subscriber.rb
+++ b/activerecord/lib/active_record/log_subscriber.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActiveRecord
   class LogSubscriber < ActiveSupport::LogSubscriber
     IGNORE_PAYLOAD_NAMES = ["SCHEMA", "EXPLAIN"]
@@ -15,40 +17,24 @@ module ActiveRecord
       rt
     end
 
-    def initialize
-      super
-      @odd = false
-    end
-
-    def render_bind(attribute)
-      value = if attribute.type.binary? && attribute.value
-        if attribute.value.is_a?(Hash)
-          "<#{attribute.value_for_database.to_s.bytesize} bytes of binary data>"
-        else
-          "<#{attribute.value.bytesize} bytes of binary data>"
-        end
-      else
-        attribute.value_for_database
-      end
-
-      [attribute.name, value]
-    end
-
     def sql(event)
-      return unless logger.debug?
-
       self.class.runtime += event.duration
+      return unless logger.debug?
 
       payload = event.payload
 
       return if IGNORE_PAYLOAD_NAMES.include?(payload[:name])
 
       name  = "#{payload[:name]} (#{event.duration.round(1)}ms)"
+      name  = "CACHE #{name}" if payload[:cached]
       sql   = payload[:sql]
       binds = nil
 
       unless (payload[:binds] || []).empty?
-        binds = "  " + payload[:binds].map { |attr| render_bind(attr) }.inspect
+        casted_params = type_casted_binds(payload[:type_casted_binds])
+        binds = "  " + payload[:binds].zip(casted_params).map { |attr, value|
+          render_bind(attr, value)
+        }.inspect
       end
 
       name = colorize_payload_name(name, payload[:name])
@@ -58,17 +44,30 @@ module ActiveRecord
     end
 
     private
+      def type_casted_binds(casted_binds)
+        casted_binds.respond_to?(:call) ? casted_binds.call : casted_binds
+      end
 
-    def colorize_payload_name(name, payload_name)
-      if payload_name.blank? || payload_name == "SQL" # SQL vs Model Load/Exists
-        color(name, MAGENTA, true)
-      else
-        color(name, CYAN, true)
+      def render_bind(attr, value)
+        if attr.is_a?(Array)
+          attr = attr.first
+        elsif attr.type.binary? && attr.value
+          value = "<#{attr.value_for_database.to_s.bytesize} bytes of binary data>"
+        end
+
+        [attr && attr.name, value]
       end
-    end
 
-    def sql_color(sql)
-      case sql
+      def colorize_payload_name(name, payload_name)
+        if payload_name.blank? || payload_name == "SQL" # SQL vs Model Load/Exists
+          color(name, MAGENTA, true)
+        else
+          color(name, CYAN, true)
+        end
+      end
+
+      def sql_color(sql)
+        case sql
         when /\A\s*rollback/mi
           RED
         when /select .*for update/mi, /\A\s*lock/mi
@@ -85,12 +84,53 @@ module ActiveRecord
           CYAN
         else
           MAGENTA
+        end
       end
-    end
 
-    def logger
-      ActiveRecord::Base.logger
-    end
+      def logger
+        ActiveRecord::Base.logger
+      end
+
+      def debug(progname = nil, &block)
+        return unless super
+
+        if ActiveRecord::Base.verbose_query_logs
+          log_query_source
+        end
+      end
+
+      def log_query_source
+        source_line, line_number = extract_callstack(caller_locations)
+
+        if source_line
+          if defined?(::Rails.root)
+            app_root = "#{::Rails.root.to_s}/".freeze
+            source_line = source_line.sub(app_root, "")
+          end
+
+          logger.debug("  ↳ #{ source_line }:#{ line_number }")
+        end
+      end
+
+      def extract_callstack(callstack)
+        line = callstack.find do |frame|
+          frame.absolute_path && !ignored_callstack(frame.absolute_path)
+        end
+
+        offending_line = line || callstack.first
+
+        [
+          offending_line.path,
+          offending_line.lineno
+        ]
+      end
+
+      RAILS_GEM_ROOT = File.expand_path("../../../..", __FILE__) + "/"
+
+      def ignored_callstack(path)
+        path.start_with?(RAILS_GEM_ROOT) ||
+        path.start_with?(RbConfig::CONFIG["rubylibdir"])
+      end
   end
 end
 
diff --git a/activerecord/lib/active_record/migration.rb b/activerecord/lib/active_record/migration.rb
index 81fe053fe1..f6648a4e3d 100644
--- a/activerecord/lib/active_record/migration.rb
+++ b/activerecord/lib/active_record/migration.rb
@@ -1,5 +1,8 @@
+# frozen_string_literal: true
+
+require "set"
+require "zlib"
 require "active_support/core_ext/module/attribute_accessors"
-require 'set'
 
 module ActiveRecord
   class MigrationError < ActiveRecordError#:nodoc:
@@ -126,9 +129,9 @@ module ActiveRecord
   class PendingMigrationError < MigrationError#:nodoc:
     def initialize(message = nil)
       if !message && defined?(Rails.env)
-        super("Migrations are pending. To resolve this issue, run:\n\n\tbin/rails db:migrate RAILS_ENV=#{::Rails.env}")
+        super("Migrations are pending. To resolve this issue, run:\n\n        bin/rails db:migrate RAILS_ENV=#{::Rails.env}")
       elsif !message
-        super("Migrations are pending. To resolve this issue, run:\n\n\tbin/rails db:migrate")
+        super("Migrations are pending. To resolve this issue, run:\n\n        bin/rails db:migrate")
       else
         super
       end
@@ -145,7 +148,7 @@ module ActiveRecord
 
   class NoEnvironmentInSchemaError < MigrationError #:nodoc:
     def initialize
-      msg = "Environment data not found in the schema. To resolve this issue, run: \n\n\tbin/rails db:environment:set"
+      msg = "Environment data not found in the schema. To resolve this issue, run: \n\n        bin/rails db:environment:set"
       if defined?(Rails.env)
         super("#{msg} RAILS_ENV=#{::Rails.env}")
       else
@@ -156,7 +159,7 @@ module ActiveRecord
 
   class ProtectedEnvironmentError < ActiveRecordError #:nodoc:
     def initialize(env = "production")
-      msg = "You are attempting to run a destructive action against your '#{env}' database.\n"
+      msg = "You are attempting to run a destructive action against your '#{env}' database.\n".dup
       msg << "If you are sure you want to continue, run the same command with the environment variable:\n"
       msg << "DISABLE_DATABASE_ENVIRONMENT_CHECK=1"
       super(msg)
@@ -165,10 +168,10 @@ module ActiveRecord
 
   class EnvironmentMismatchError < ActiveRecordError
     def initialize(current: nil, stored: nil)
-      msg =  "You are attempting to modify a database that was last run in `#{ stored }` environment.\n"
+      msg =  "You are attempting to modify a database that was last run in `#{ stored }` environment.\n".dup
       msg << "You are running in `#{ current }` environment. "
       msg << "If you are sure you want to continue, first set the environment using:\n\n"
-      msg << "\tbin/rails db:environment:set"
+      msg << "        bin/rails db:environment:set"
       if defined?(Rails.env)
         super("#{msg} RAILS_ENV=#{::Rails.env}\n\n")
       else
@@ -276,8 +279,10 @@ module ActiveRecord
   #
   # * <tt>change_column(table_name, column_name, type, options)</tt>:  Changes
   #   the column to a different type using the same parameters as add_column.
-  # * <tt>change_column_default(table_name, column_name, default)</tt>: Sets a
-  #   default value for +column_name+ defined by +default+ on +table_name+.
+  # * <tt>change_column_default(table_name, column_name, default_or_changes)</tt>:
+  #   Sets a default value for +column_name+ defined by +default_or_changes+ on
+  #   +table_name+. Passing a hash containing <tt>:from</tt> and <tt>:to</tt>
+  #   as +default_or_changes+ will make this change reversible in the migration.
   # * <tt>change_column_null(table_name, column_name, null, default = nil)</tt>:
   #   Sets or removes a +NOT NULL+ constraint on +column_name+. The +null+ flag
   #   indicates whether the value can be +NULL+. See
@@ -349,9 +354,9 @@ module ActiveRecord
   # to match the structure of your database.
   #
   # To roll the database back to a previous migration version, use
-  # <tt>rails db:migrate VERSION=X</tt> where <tt>X</tt> is the version to which
+  # <tt>rails db:rollback VERSION=X</tt> where <tt>X</tt> is the version to which
   # you wish to downgrade. Alternatively, you can also use the STEP option if you
-  # wish to rollback last few migrations. <tt>rails db:migrate STEP=2</tt> will rollback
+  # wish to rollback last few migrations. <tt>rails db:rollback STEP=2</tt> will rollback
   # the latest two migrations.
   #
   # If any of the migrations throw an <tt>ActiveRecord::IrreversibleMigration</tt> exception,
@@ -509,8 +514,8 @@ module ActiveRecord
   # Remember that you can still open your own transactions, even if you
   # are in a Migration with <tt>self.disable_ddl_transaction!</tt>.
   class Migration
-    autoload :CommandRecorder, 'active_record/migration/command_recorder'
-    autoload :Compatibility, 'active_record/migration/compatibility'
+    autoload :CommandRecorder, "active_record/migration/command_recorder"
+    autoload :Compatibility, "active_record/migration/compatibility"
 
     # This must be defined before the inherited hook, below
     class Current < Migration # :nodoc:
@@ -519,7 +524,10 @@ module ActiveRecord
     def self.inherited(subclass) # :nodoc:
       super
       if subclass.superclass == Migration
-        subclass.include Compatibility::Legacy
+        raise StandardError, "Directly inheriting from ActiveRecord::Migration is not supported. " \
+          "Please specify the Rails release the migration was written for:\n" \
+          "\n" \
+          "  class #{subclass} < ActiveRecord::Migration[4.2]"
       end
     end
 
@@ -542,21 +550,19 @@ module ActiveRecord
       end
 
       def call(env)
-        if connection.supports_migrations?
-          mtime = ActiveRecord::Migrator.last_migration.mtime.to_i
-          if @last_check < mtime
-            ActiveRecord::Migration.check_pending!(connection)
-            @last_check = mtime
-          end
+        mtime = ActiveRecord::Migrator.last_migration.mtime.to_i
+        if @last_check < mtime
+          ActiveRecord::Migration.check_pending!(connection)
+          @last_check = mtime
         end
         @app.call(env)
       end
 
       private
 
-      def connection
-        ActiveRecord::Base.connection
-      end
+        def connection
+          ActiveRecord::Base.connection
+        end
     end
 
     class << self
@@ -575,7 +581,8 @@ module ActiveRecord
       def load_schema_if_pending!
         if ActiveRecord::Migrator.needs_migration? || !ActiveRecord::Migrator.any_migrations?
           # Roundtrip to Rake to allow plugins to hook into database initialization.
-          FileUtils.cd Rails.root do
+          root = defined?(ENGINE_ROOT) ? ENGINE_ROOT : Rails.root
+          FileUtils.cd(root) do
             current_config = Base.connection_config
             Base.clear_all_connections!
             system("bin/rails db:test:prepare")
@@ -686,7 +693,7 @@ module ActiveRecord
       connection.respond_to?(:reverting) && connection.reverting
     end
 
-    class ReversibleBlockHelper < Struct.new(:reverting) # :nodoc:
+    ReversibleBlockHelper = Struct.new(:reverting) do # :nodoc:
       def up
         yield unless reverting
       end
@@ -724,7 +731,25 @@ module ActiveRecord
     #    end
     def reversible
       helper = ReversibleBlockHelper.new(reverting?)
-      execute_block{ yield helper }
+      execute_block { yield helper }
+    end
+
+    # Used to specify an operation that is only run when migrating up
+    # (for example, populating a new column with its initial values).
+    #
+    # In the following example, the new column +published+ will be given
+    # the value +true+ for all existing records.
+    #
+    #    class AddPublishedToPosts < ActiveRecord::Migration[5.2]
+    #      def change
+    #        add_column :posts, :published, :boolean, default: false
+    #        up_only do
+    #          execute "update posts set published = 'true'"
+    #        end
+    #      end
+    #    end
+    def up_only
+      execute_block { yield } unless reverting?
     end
 
     # Runs the given migration classes.
@@ -766,7 +791,7 @@ module ActiveRecord
       when :down then announce "reverting"
       end
 
-      time   = nil
+      time = nil
       ActiveRecord::Base.connection_pool.with_connection do |conn|
         time = Benchmark.measure do
           exec_migration(conn, direction)
@@ -794,7 +819,7 @@ module ActiveRecord
       @connection = nil
     end
 
-    def write(text="")
+    def write(text = "")
       puts(text) if verbose
     end
 
@@ -804,7 +829,7 @@ module ActiveRecord
       write "== %s %s" % [text, "=" * length]
     end
 
-    def say(message, subitem=false)
+    def say(message, subitem = false)
       write "#{subitem ? "   ->" : "--"} #{message}"
     end
 
@@ -829,7 +854,7 @@ module ActiveRecord
     end
 
     def method_missing(method, *arguments, &block)
-      arg_list = arguments.map(&:inspect) * ', '
+      arg_list = arguments.map(&:inspect) * ", "
 
       say_with_time "#{method}(#{arg_list})" do
         unless connection.respond_to? :revert
@@ -859,15 +884,17 @@ module ActiveRecord
         source_migrations.each do |migration|
           source = File.binread(migration.filename)
           inserted_comment = "# This migration comes from #{scope} (originally #{migration.version})\n"
-          if /\A#.*\b(?:en)?coding:\s*\S+/ =~ source
+          magic_comments = "".dup
+          loop do
             # If we have a magic comment in the original migration,
             # insert our comment after the first newline(end of the magic comment line)
             # so the magic keep working.
             # Note that magic comments must be at the first line(except sh-bang).
-            source[/\n/] = "\n#{inserted_comment}"
-          else
-            source = "#{inserted_comment}#{source}"
+            source.sub!(/\A(?:#.*\b(?:en)?coding:\s*\S+|#\s*frozen_string_literal:\s*(?:true|false)).*\n/) do |magic_comment|
+              magic_comments << magic_comment; ""
+            end || break
           end
+          source = "#{magic_comments}#{inserted_comment}#{source}"
 
           if duplicate = destination_migrations.detect { |m| m.name == migration.name }
             if options[:on_skip] && duplicate.scope != scope.to_s
@@ -921,19 +948,18 @@ module ActiveRecord
     end
 
     private
-    def execute_block
-      if connection.respond_to? :execute_block
-        super # use normal delegation to record the block
-      else
-        yield
+      def execute_block
+        if connection.respond_to? :execute_block
+          super # use normal delegation to record the block
+        else
+          yield
+        end
       end
-    end
   end
 
   # MigrationProxy is used to defer loading of the actual migration classes
   # until they are needed
-  class MigrationProxy < Struct.new(:name, :version, :filename, :scope)
-
+  MigrationProxy = Struct.new(:name, :version, :filename, :scope) do
     def initialize(name, version, filename, scope)
       super
       @migration = nil
@@ -959,7 +985,6 @@ module ActiveRecord
         require(File.expand_path(filename))
         name.constantize.new(name, version)
       end
-
   end
 
   class NullMigration < MigrationProxy #:nodoc:
@@ -990,11 +1015,11 @@ module ActiveRecord
         end
       end
 
-      def rollback(migrations_paths, steps=1)
+      def rollback(migrations_paths, steps = 1)
         move(:down, migrations_paths, steps)
       end
 
-      def forward(migrations_paths, steps=1)
+      def forward(migrations_paths, steps = 1)
         move(:up, migrations_paths, steps)
       end
 
@@ -1020,26 +1045,21 @@ module ActiveRecord
         new(:up, migrations(migrations_paths), nil)
       end
 
-      def schema_migrations_table_name
-        SchemaMigration.table_name
-      end
-
-      def get_all_versions(connection = Base.connection)
-        ActiveSupport::Deprecation.silence do
-          if connection.table_exists?(schema_migrations_table_name)
-            SchemaMigration.all.map { |x| x.version.to_i }.sort
-          else
-            []
-          end
+      def get_all_versions
+        if SchemaMigration.table_exists?
+          SchemaMigration.all_versions.map(&:to_i)
+        else
+          []
         end
       end
 
-      def current_version(connection = Base.connection)
-        get_all_versions(connection).max || 0
+      def current_version(connection = nil)
+        get_all_versions.max || 0
+      rescue ActiveRecord::NoDatabaseError
       end
 
-      def needs_migration?(connection = Base.connection)
-        (migrations(migrations_paths).collect(&:version) - get_all_versions(connection)).size > 0
+      def needs_migration?(connection = nil)
+        (migrations(migrations_paths).collect(&:version) - get_all_versions).size > 0
       end
 
       def any_migrations?
@@ -1051,15 +1071,11 @@ module ActiveRecord
       end
 
       def migrations_paths
-        @migrations_paths ||= ['db/migrate']
+        @migrations_paths ||= ["db/migrate"]
         # just to not break things if someone uses: migrations_path = some_string
         Array(@migrations_paths)
       end
 
-      def match_to_migration_filename?(filename) # :nodoc:
-        File.basename(filename) =~ Migration::MigrationFilenameRegexp
-      end
-
       def parse_migration_filename(filename) # :nodoc:
         File.basename(filename).scan(Migration::MigrationFilenameRegexp).first
       end
@@ -1067,9 +1083,7 @@ module ActiveRecord
       def migrations(paths)
         paths = Array(paths)
 
-        files = Dir[*paths.map { |p| "#{p}/**/[0-9]*_*.rb" }]
-
-        migrations = files.map do |file|
+        migrations = migration_files(paths).map do |file|
           version, name, scope = parse_migration_filename(file)
           raise IllegalMigrationNameError.new(file) unless version
           version = version.to_i
@@ -1081,23 +1095,53 @@ module ActiveRecord
         migrations.sort_by(&:version)
       end
 
+      def migrations_status(paths)
+        paths = Array(paths)
+
+        db_list = ActiveRecord::SchemaMigration.normalized_versions
+
+        file_list = migration_files(paths).map do |file|
+          version, name, scope = parse_migration_filename(file)
+          raise IllegalMigrationNameError.new(file) unless version
+          version = ActiveRecord::SchemaMigration.normalize_migration_number(version)
+          status = db_list.delete(version) ? "up" : "down"
+          [status, version, (name + scope).humanize]
+        end.compact
+
+        db_list.map! do |version|
+          ["up", version, "********** NO FILE **********"]
+        end
+
+        (db_list + file_list).sort_by { |_, version, _| version }
+      end
+
+      def migration_files(paths)
+        Dir[*paths.flat_map { |path| "#{path}/**/[0-9]*_*.rb" }]
+      end
+
       private
 
       def move(direction, migrations_paths, steps)
         migrator = new(direction, migrations(migrations_paths))
-        start_index = migrator.migrations.index(migrator.current_migration)
 
-        if start_index
-          finish = migrator.migrations[start_index + steps]
-          version = finish ? finish.version : 0
-          send(direction, migrations_paths, version)
+        if current_version != 0 && !migrator.current_migration
+          raise UnknownMigrationVersionError.new(current_version)
         end
+
+        start_index =
+          if current_version == 0
+            0
+          else
+            migrator.migrations.index(migrator.current_migration)
+          end
+
+        finish = migrator.migrations[start_index + steps]
+        version = finish ? finish.version : 0
+        send(direction, migrations_paths, version)
       end
     end
 
     def initialize(direction, migrations, target_version = nil)
-      raise StandardError.new("This database does not yet support migrations") unless Base.connection.supports_migrations?
-
       @direction         = direction
       @target_version    = target_version
       @migrated_versions = nil
@@ -1105,8 +1149,8 @@ module ActiveRecord
 
       validate(@migrations)
 
-      Base.connection.initialize_schema_migrations_table
-      Base.connection.initialize_internal_metadata_table
+      ActiveRecord::SchemaMigration.create_table
+      ActiveRecord::InternalMetadata.create_table
     end
 
     def current_version
@@ -1164,146 +1208,148 @@ module ActiveRecord
 
     private
 
-    # Used for running a specific migration.
-    def run_without_lock
-      migration = migrations.detect { |m| m.version == @target_version }
-      raise UnknownMigrationVersionError.new(@target_version) if migration.nil?
-      execute_migration_in_transaction(migration, @direction)
-
-      record_environment
-    end
+      # Used for running a specific migration.
+      def run_without_lock
+        migration = migrations.detect { |m| m.version == @target_version }
+        raise UnknownMigrationVersionError.new(@target_version) if migration.nil?
+        result = execute_migration_in_transaction(migration, @direction)
 
-    # Used for running multiple migrations up to or down to a certain value.
-    def migrate_without_lock
-      if invalid_target?
-        raise UnknownMigrationVersionError.new(@target_version)
+        record_environment
+        result
       end
 
-      runnable.each do |migration|
-        execute_migration_in_transaction(migration, @direction)
-      end
+      # Used for running multiple migrations up to or down to a certain value.
+      def migrate_without_lock
+        if invalid_target?
+          raise UnknownMigrationVersionError.new(@target_version)
+        end
 
-      record_environment
-    end
+        result = runnable.each do |migration|
+          execute_migration_in_transaction(migration, @direction)
+        end
 
-    # Stores the current environment in the database.
-    def record_environment
-      return if down?
-      ActiveRecord::InternalMetadata[:environment] = ActiveRecord::Migrator.current_environment
-    end
+        record_environment
+        result
+      end
 
-    def ran?(migration)
-      migrated.include?(migration.version.to_i)
-    end
+      # Stores the current environment in the database.
+      def record_environment
+        return if down?
+        ActiveRecord::InternalMetadata[:environment] = ActiveRecord::Migrator.current_environment
+      end
 
-    # Return true if a valid version is not provided.
-    def invalid_target?
-      !target && @target_version && @target_version > 0
-    end
+      def ran?(migration)
+        migrated.include?(migration.version.to_i)
+      end
+
+      # Return true if a valid version is not provided.
+      def invalid_target?
+        @target_version && @target_version != 0 && !target
+      end
 
-    def execute_migration_in_transaction(migration, direction)
-      return if down? && !migrated.include?(migration.version.to_i)
-      return if up?   &&  migrated.include?(migration.version.to_i)
+      def execute_migration_in_transaction(migration, direction)
+        return if down? && !migrated.include?(migration.version.to_i)
+        return if up?   &&  migrated.include?(migration.version.to_i)
 
-      Base.logger.info "Migrating to #{migration.name} (#{migration.version})" if Base.logger
+        Base.logger.info "Migrating to #{migration.name} (#{migration.version})" if Base.logger
 
-      ddl_transaction(migration) do
-        migration.migrate(direction)
-        record_version_state_after_migrating(migration.version)
+        ddl_transaction(migration) do
+          migration.migrate(direction)
+          record_version_state_after_migrating(migration.version)
+        end
+      rescue => e
+        msg = "An error has occurred, ".dup
+        msg << "this and " if use_transaction?(migration)
+        msg << "all later migrations canceled:\n\n#{e}"
+        raise StandardError, msg, e.backtrace
       end
-    rescue => e
-      msg = "An error has occurred, "
-      msg << "this and " if use_transaction?(migration)
-      msg << "all later migrations canceled:\n\n#{e}"
-      raise StandardError, msg, e.backtrace
-    end
 
-    def target
-      migrations.detect { |m| m.version == @target_version }
-    end
+      def target
+        migrations.detect { |m| m.version == @target_version }
+      end
 
-    def finish
-      migrations.index(target) || migrations.size - 1
-    end
+      def finish
+        migrations.index(target) || migrations.size - 1
+      end
 
-    def start
-      up? ? 0 : (migrations.index(current) || 0)
-    end
+      def start
+        up? ? 0 : (migrations.index(current) || 0)
+      end
 
-    def validate(migrations)
-      name ,= migrations.group_by(&:name).find { |_,v| v.length > 1 }
-      raise DuplicateMigrationNameError.new(name) if name
+      def validate(migrations)
+        name, = migrations.group_by(&:name).find { |_, v| v.length > 1 }
+        raise DuplicateMigrationNameError.new(name) if name
 
-      version ,= migrations.group_by(&:version).find { |_,v| v.length > 1 }
-      raise DuplicateMigrationVersionError.new(version) if version
-    end
+        version, = migrations.group_by(&:version).find { |_, v| v.length > 1 }
+        raise DuplicateMigrationVersionError.new(version) if version
+      end
 
-    def record_version_state_after_migrating(version)
-      if down?
-        migrated.delete(version)
-        ActiveRecord::SchemaMigration.where(:version => version.to_s).delete_all
-      else
-        migrated << version
-        ActiveRecord::SchemaMigration.create!(version: version.to_s)
+      def record_version_state_after_migrating(version)
+        if down?
+          migrated.delete(version)
+          ActiveRecord::SchemaMigration.where(version: version.to_s).delete_all
+        else
+          migrated << version
+          ActiveRecord::SchemaMigration.create!(version: version.to_s)
+        end
       end
-    end
 
-    def self.last_stored_environment
-      return nil if current_version == 0
-      raise NoEnvironmentInSchemaError unless ActiveRecord::InternalMetadata.table_exists?
+      def self.last_stored_environment
+        return nil if current_version == 0
+        raise NoEnvironmentInSchemaError unless ActiveRecord::InternalMetadata.table_exists?
 
-      environment = ActiveRecord::InternalMetadata[:environment]
-      raise NoEnvironmentInSchemaError unless environment
-      environment
-    end
+        environment = ActiveRecord::InternalMetadata[:environment]
+        raise NoEnvironmentInSchemaError unless environment
+        environment
+      end
 
-    def self.current_environment
-      ActiveRecord::ConnectionHandling::DEFAULT_ENV.call
-    end
+      def self.current_environment
+        ActiveRecord::ConnectionHandling::DEFAULT_ENV.call
+      end
 
-    def self.protected_environment?
-      ActiveRecord::Base.protected_environments.include?(last_stored_environment) if last_stored_environment
-    end
+      def self.protected_environment?
+        ActiveRecord::Base.protected_environments.include?(last_stored_environment) if last_stored_environment
+      end
 
-    def up?
-      @direction == :up
-    end
+      def up?
+        @direction == :up
+      end
 
-    def down?
-      @direction == :down
-    end
+      def down?
+        @direction == :down
+      end
 
-    # Wrap the migration in a transaction only if supported by the adapter.
-    def ddl_transaction(migration)
-      if use_transaction?(migration)
-        Base.transaction { yield }
-      else
-        yield
+      # Wrap the migration in a transaction only if supported by the adapter.
+      def ddl_transaction(migration)
+        if use_transaction?(migration)
+          Base.transaction { yield }
+        else
+          yield
+        end
       end
-    end
 
-    def use_transaction?(migration)
-      !migration.disable_ddl_transaction && Base.connection.supports_ddl_transactions?
-    end
+      def use_transaction?(migration)
+        !migration.disable_ddl_transaction && Base.connection.supports_ddl_transactions?
+      end
 
-    def use_advisory_lock?
-      Base.connection.supports_advisory_locks?
-    end
+      def use_advisory_lock?
+        Base.connection.supports_advisory_locks?
+      end
 
-    def with_advisory_lock
-      lock_id = generate_migrator_advisory_lock_id
-      got_lock = Base.connection.get_advisory_lock(lock_id)
-      raise ConcurrentMigrationError unless got_lock
-      load_migrated # reload schema_migrations to be sure it wasn't changed by another process before we got the lock
-      yield
-    ensure
-      Base.connection.release_advisory_lock(lock_id) if got_lock
-    end
+      def with_advisory_lock
+        lock_id = generate_migrator_advisory_lock_id
+        got_lock = Base.connection.get_advisory_lock(lock_id)
+        raise ConcurrentMigrationError unless got_lock
+        load_migrated # reload schema_migrations to be sure it wasn't changed by another process before we got the lock
+        yield
+      ensure
+        Base.connection.release_advisory_lock(lock_id) if got_lock
+      end
 
-    MIGRATOR_SALT = 2053462845
-    def generate_migrator_advisory_lock_id
-      db_name_hash = Zlib.crc32(Base.connection.current_database)
-      MIGRATOR_SALT * db_name_hash
-    end
+      MIGRATOR_SALT = 2053462845
+      def generate_migrator_advisory_lock_id
+        db_name_hash = Zlib.crc32(Base.connection.current_database)
+        MIGRATOR_SALT * db_name_hash
+      end
   end
 end
diff --git a/activerecord/lib/active_record/migration/command_recorder.rb b/activerecord/lib/active_record/migration/command_recorder.rb
index 0fa665c7e0..81ef4828f8 100644
--- a/activerecord/lib/active_record/migration/command_recorder.rb
+++ b/activerecord/lib/active_record/migration/command_recorder.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActiveRecord
   class Migration
     # <tt>ActiveRecord::Migration::CommandRecorder</tt> records commands done during
@@ -92,10 +94,6 @@ module ActiveRecord
         send(method, args, &block)
       end
 
-      def respond_to?(*args) # :nodoc:
-        super || delegate.respond_to?(*args)
-      end
-
       ReversibleAndIrreversibleMethods.each do |method|
         class_eval <<-EOV, __FILE__, __LINE__ + 1
           def #{method}(*args, &block)          # def create_table(*args, &block)
@@ -112,127 +110,131 @@ module ActiveRecord
 
       private
 
-      module StraightReversions
-        private
-        { transaction:       :transaction,
-          execute_block:     :execute_block,
-          create_table:      :drop_table,
-          create_join_table: :drop_join_table,
-          add_column:        :remove_column,
-          add_timestamps:    :remove_timestamps,
-          add_reference:     :remove_reference,
-          enable_extension:  :disable_extension
-        }.each do |cmd, inv|
-          [[inv, cmd], [cmd, inv]].uniq.each do |method, inverse|
-            class_eval <<-EOV, __FILE__, __LINE__ + 1
-              def invert_#{method}(args, &block)    # def invert_create_table(args, &block)
-                [:#{inverse}, args, block]          #   [:drop_table, args, block]
-              end                                   # end
-            EOV
-          end
+        module StraightReversions # :nodoc:
+          private
+            { transaction:       :transaction,
+              execute_block:     :execute_block,
+              create_table:      :drop_table,
+              create_join_table: :drop_join_table,
+              add_column:        :remove_column,
+              add_timestamps:    :remove_timestamps,
+              add_reference:     :remove_reference,
+              enable_extension:  :disable_extension
+            }.each do |cmd, inv|
+              [[inv, cmd], [cmd, inv]].uniq.each do |method, inverse|
+                class_eval <<-EOV, __FILE__, __LINE__ + 1
+                  def invert_#{method}(args, &block)    # def invert_create_table(args, &block)
+                    [:#{inverse}, args, block]          #   [:drop_table, args, block]
+                  end                                   # end
+                EOV
+              end
+            end
         end
-      end
 
-      include StraightReversions
+        include StraightReversions
 
-      def invert_drop_table(args, &block)
-        if args.size == 1 && block == nil
-          raise ActiveRecord::IrreversibleMigration, "To avoid mistakes, drop_table is only reversible if given options or a block (can be empty)."
+        def invert_drop_table(args, &block)
+          if args.size == 1 && block == nil
+            raise ActiveRecord::IrreversibleMigration, "To avoid mistakes, drop_table is only reversible if given options or a block (can be empty)."
+          end
+          super
         end
-        super
-      end
 
-      def invert_rename_table(args)
-        [:rename_table, args.reverse]
-      end
+        def invert_rename_table(args)
+          [:rename_table, args.reverse]
+        end
 
-      def invert_remove_column(args)
-        raise ActiveRecord::IrreversibleMigration, "remove_column is only reversible if given a type." if args.size <= 2
-        super
-      end
+        def invert_remove_column(args)
+          raise ActiveRecord::IrreversibleMigration, "remove_column is only reversible if given a type." if args.size <= 2
+          super
+        end
 
-      def invert_rename_index(args)
-        [:rename_index, [args.first] + args.last(2).reverse]
-      end
+        def invert_rename_index(args)
+          [:rename_index, [args.first] + args.last(2).reverse]
+        end
 
-      def invert_rename_column(args)
-        [:rename_column, [args.first] + args.last(2).reverse]
-      end
+        def invert_rename_column(args)
+          [:rename_column, [args.first] + args.last(2).reverse]
+        end
 
-      def invert_add_index(args)
-        table, columns, options = *args
-        options ||= {}
+        def invert_add_index(args)
+          table, columns, options = *args
+          options ||= {}
 
-        index_name = options[:name]
-        options_hash = index_name ? { name: index_name } : { column: columns }
+          options_hash = options.slice(:name, :algorithm)
+          options_hash[:column] = columns if !options_hash[:name]
 
-        [:remove_index, [table, options_hash]]
-      end
+          [:remove_index, [table, options_hash]]
+        end
 
-      def invert_remove_index(args)
-        table, options_or_column = *args
-        if (options = options_or_column).is_a?(Hash)
-          unless options[:column]
-            raise ActiveRecord::IrreversibleMigration, "remove_index is only reversible if given a :column option."
+        def invert_remove_index(args)
+          table, options_or_column = *args
+          if (options = options_or_column).is_a?(Hash)
+            unless options[:column]
+              raise ActiveRecord::IrreversibleMigration, "remove_index is only reversible if given a :column option."
+            end
+            options = options.dup
+            [:add_index, [table, options.delete(:column), options]]
+          elsif (column = options_or_column).present?
+            [:add_index, [table, column]]
           end
-          options = options.dup
-          [:add_index, [table, options.delete(:column), options]]
-        elsif (column = options_or_column).present?
-          [:add_index, [table, column]]
         end
-      end
 
-      alias :invert_add_belongs_to :invert_add_reference
-      alias :invert_remove_belongs_to :invert_remove_reference
+        alias :invert_add_belongs_to :invert_add_reference
+        alias :invert_remove_belongs_to :invert_remove_reference
 
-      def invert_change_column_default(args)
-        table, column, options = *args
+        def invert_change_column_default(args)
+          table, column, options = *args
 
-        unless options && options.is_a?(Hash) && options.has_key?(:from) && options.has_key?(:to)
-          raise ActiveRecord::IrreversibleMigration, "change_column_default is only reversible if given a :from and :to option."
+          unless options && options.is_a?(Hash) && options.has_key?(:from) && options.has_key?(:to)
+            raise ActiveRecord::IrreversibleMigration, "change_column_default is only reversible if given a :from and :to option."
+          end
+
+          [:change_column_default, [table, column, from: options[:to], to: options[:from]]]
         end
 
-        [:change_column_default, [table, column, from: options[:to], to: options[:from]]]
-      end
+        def invert_change_column_null(args)
+          args[2] = !args[2]
+          [:change_column_null, args]
+        end
 
-      def invert_change_column_null(args)
-        args[2] = !args[2]
-        [:change_column_null, args]
-      end
+        def invert_add_foreign_key(args)
+          from_table, to_table, add_options = args
+          add_options ||= {}
 
-      def invert_add_foreign_key(args)
-        from_table, to_table, add_options = args
-        add_options ||= {}
+          if add_options[:name]
+            options = { name: add_options[:name] }
+          elsif add_options[:column]
+            options = { column: add_options[:column] }
+          else
+            options = to_table
+          end
 
-        if add_options[:name]
-          options = { name: add_options[:name] }
-        elsif add_options[:column]
-          options = { column: add_options[:column] }
-        else
-          options = to_table
+          [:remove_foreign_key, [from_table, options]]
         end
 
-        [:remove_foreign_key, [from_table, options]]
-      end
+        def invert_remove_foreign_key(args)
+          from_table, to_table, remove_options = args
+          raise ActiveRecord::IrreversibleMigration, "remove_foreign_key is only reversible if given a second table" if to_table.nil? || to_table.is_a?(Hash)
 
-      def invert_remove_foreign_key(args)
-        from_table, to_table, remove_options = args
-        raise ActiveRecord::IrreversibleMigration, "remove_foreign_key is only reversible if given a second table" if to_table.nil? || to_table.is_a?(Hash)
+          reversed_args = [from_table, to_table]
+          reversed_args << remove_options if remove_options
 
-        reversed_args = [from_table, to_table]
-        reversed_args << remove_options if remove_options
+          [:add_foreign_key, reversed_args]
+        end
 
-        [:add_foreign_key, reversed_args]
-      end
+        def respond_to_missing?(method, _)
+          super || delegate.respond_to?(method)
+        end
 
-      # Forwards any missing method call to the \target.
-      def method_missing(method, *args, &block)
-        if @delegate.respond_to?(method)
-          @delegate.send(method, *args, &block)
-        else
-          super
+        # Forwards any missing method call to the \target.
+        def method_missing(method, *args, &block)
+          if delegate.respond_to?(method)
+            delegate.public_send(method, *args, &block)
+          else
+            super
+          end
         end
-      end
     end
   end
 end
diff --git a/activerecord/lib/active_record/migration/compatibility.rb b/activerecord/lib/active_record/migration/compatibility.rb
index 74833f938f..7ae8073478 100644
--- a/activerecord/lib/active_record/migration/compatibility.rb
+++ b/activerecord/lib/active_record/migration/compatibility.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActiveRecord
   class Migration
     module Compatibility # :nodoc: all
@@ -5,15 +7,124 @@ module ActiveRecord
         version = version.to_s
         name = "V#{version.tr('.', '_')}"
         unless const_defined?(name)
-          versions = constants.grep(/\AV[0-9_]+\z/).map { |s| s.to_s.delete('V').tr('_', '.').inspect }
+          versions = constants.grep(/\AV[0-9_]+\z/).map { |s| s.to_s.delete("V").tr("_", ".").inspect }
           raise ArgumentError, "Unknown migration version #{version.inspect}; expected one of #{versions.sort.join(', ')}"
         end
         const_get(name)
       end
 
-      V5_1 = Current
+      V5_2 = Current
+
+      class V5_1 < V5_2
+        def change_column(table_name, column_name, type, options = {})
+          if adapter_name == "PostgreSQL"
+            clear_cache!
+            sql = connection.send(:change_column_sql, table_name, column_name, type, options)
+            execute "ALTER TABLE #{quote_table_name(table_name)} #{sql}"
+            change_column_default(table_name, column_name, options[:default]) if options.key?(:default)
+            change_column_null(table_name, column_name, options[:null], options[:default]) if options.key?(:null)
+            change_column_comment(table_name, column_name, options[:comment]) if options.key?(:comment)
+          else
+            super
+          end
+        end
+
+        def create_table(table_name, options = {})
+          if adapter_name == "Mysql2"
+            super(table_name, options: "ENGINE=InnoDB", **options)
+          else
+            super
+          end
+        end
+      end
+
+      class V5_0 < V5_1
+        module TableDefinition
+          def primary_key(name, type = :primary_key, **options)
+            type = :integer if type == :primary_key
+            super
+          end
+
+          def references(*args, **options)
+            super(*args, type: :integer, **options)
+          end
+          alias :belongs_to :references
+        end
+
+        def create_table(table_name, options = {})
+          if adapter_name == "PostgreSQL"
+            if options[:id] == :uuid && !options.key?(:default)
+              options[:default] = "uuid_generate_v4()"
+            end
+          end
+
+          unless adapter_name == "Mysql2" && options[:id] == :bigint
+            if [:integer, :bigint].include?(options[:id]) && !options.key?(:default)
+              options[:default] = nil
+            end
+          end
+
+          # Since 5.1 PostgreSQL adapter uses bigserial type for primary
+          # keys by default and MySQL uses bigint. This compat layer makes old migrations utilize
+          # serial/int type instead -- the way it used to work before 5.1.
+          unless options.key?(:id)
+            options[:id] = :integer
+          end
+
+          if block_given?
+            super do |t|
+              yield compatible_table_definition(t)
+            end
+          else
+            super
+          end
+        end
+
+        def change_table(table_name, options = {})
+          if block_given?
+            super do |t|
+              yield compatible_table_definition(t)
+            end
+          else
+            super
+          end
+        end
+
+        def create_join_table(table_1, table_2, column_options: {}, **options)
+          column_options.reverse_merge!(type: :integer)
+
+          if block_given?
+            super do |t|
+              yield compatible_table_definition(t)
+            end
+          else
+            super
+          end
+        end
+
+        def add_column(table_name, column_name, type, options = {})
+          if type == :primary_key
+            type = :integer
+            options[:primary_key] = true
+          end
+          super
+        end
+
+        def add_reference(table_name, ref_name, **options)
+          super(table_name, ref_name, type: :integer, **options)
+        end
+        alias :add_belongs_to :add_reference
+
+        private
+          def compatible_table_definition(t)
+            class << t
+              prepend TableDefinition
+            end
+            t
+          end
+      end
 
-      module FourTwoShared
+      class V4_2 < V5_0
         module TableDefinition
           def references(*, **options)
             options[:index] ||= false
@@ -21,7 +132,7 @@ module ActiveRecord
           end
           alias :belongs_to :references
 
-          def timestamps(*, **options)
+          def timestamps(**options)
             options[:null] = true if options[:null].nil?
             super
           end
@@ -29,11 +140,8 @@ module ActiveRecord
 
         def create_table(table_name, options = {})
           if block_given?
-            super(table_name, options) do |t|
-              class << t
-                prepend TableDefinition
-              end
-              yield t
+            super do |t|
+              yield compatible_table_definition(t)
             end
           else
             super
@@ -42,11 +150,8 @@ module ActiveRecord
 
         def change_table(table_name, options = {})
           if block_given?
-            super(table_name, options) do |t|
-              class << t
-                prepend TableDefinition
-              end
-              yield t
+            super do |t|
+              yield compatible_table_definition(t)
             end
           else
             super
@@ -59,7 +164,7 @@ module ActiveRecord
         end
         alias :add_belongs_to :add_reference
 
-        def add_timestamps(*, **options)
+        def add_timestamps(_, **options)
           options[:null] = true if options[:null].nil?
           super
         end
@@ -82,47 +187,30 @@ module ActiveRecord
         end
 
         private
-
-        def index_name_for_remove(table_name, options = {})
-          index_name = index_name(table_name, options)
-
-          unless index_name_exists?(table_name, index_name, true)
-            if options.is_a?(Hash) && options.has_key?(:name)
-              options_without_column = options.dup
-              options_without_column.delete :column
-              index_name_without_column = index_name(table_name, options_without_column)
-
-              return index_name_without_column if index_name_exists?(table_name, index_name_without_column, false)
+          def compatible_table_definition(t)
+            class << t
+              prepend TableDefinition
             end
-
-            raise ArgumentError, "Index name '#{index_name}' on table '#{table_name}' does not exist"
+            super
           end
 
-          index_name
-        end
-      end
+          def index_name_for_remove(table_name, options = {})
+            index_name = index_name(table_name, options)
 
-      class V5_0 < V5_1
-      end
+            unless index_name_exists?(table_name, index_name)
+              if options.is_a?(Hash) && options.has_key?(:name)
+                options_without_column = options.dup
+                options_without_column.delete :column
+                index_name_without_column = index_name(table_name, options_without_column)
 
-      class V4_2 < V5_0
-        # 4.2 is defined as a module because it needs to be shared with
-        # Legacy. When the time comes, V5_0 should be defined straight
-        # in its class.
-        include FourTwoShared
-      end
+                return index_name_without_column if index_name_exists?(table_name, index_name_without_column)
+              end
 
-      module Legacy
-        include FourTwoShared
+              raise ArgumentError, "Index name '#{index_name}' on table '#{table_name}' does not exist"
+            end
 
-        def migrate(*)
-          ActiveSupport::Deprecation.warn \
-            "Directly inheriting from ActiveRecord::Migration is deprecated. " \
-            "Please specify the Rails release the migration was written for:\n" \
-            "\n" \
-            "  class #{self.class.name} < ActiveRecord::Migration[4.2]"
-          super
-        end
+            index_name
+          end
       end
     end
   end
diff --git a/activerecord/lib/active_record/migration/join_table.rb b/activerecord/lib/active_record/migration/join_table.rb
index 05569fadbd..9abb289bb0 100644
--- a/activerecord/lib/active_record/migration/join_table.rb
+++ b/activerecord/lib/active_record/migration/join_table.rb
@@ -1,15 +1,17 @@
+# frozen_string_literal: true
+
 module ActiveRecord
   class Migration
     module JoinTable #:nodoc:
       private
 
-      def find_join_table_name(table_1, table_2, options = {})
-        options.delete(:table_name) || join_table_name(table_1, table_2)
-      end
+        def find_join_table_name(table_1, table_2, options = {})
+          options.delete(:table_name) || join_table_name(table_1, table_2)
+        end
 
-      def join_table_name(table_1, table_2)
-        ModelSchema.derive_join_table_name(table_1, table_2).to_sym
-      end
+        def join_table_name(table_1, table_2)
+          ModelSchema.derive_join_table_name(table_1, table_2).to_sym
+        end
     end
   end
 end
diff --git a/activerecord/lib/active_record/model_schema.rb b/activerecord/lib/active_record/model_schema.rb
index 7996c32bbc..fa7537c1a3 100644
--- a/activerecord/lib/active_record/model_schema.rb
+++ b/activerecord/lib/active_record/model_schema.rb
@@ -1,78 +1,123 @@
+# frozen_string_literal: true
+
+require "monitor"
+
 module ActiveRecord
   module ModelSchema
     extend ActiveSupport::Concern
 
+    ##
+    # :singleton-method: primary_key_prefix_type
+    # :call-seq: primary_key_prefix_type
+    #
+    # The prefix type that will be prepended to every primary key column name.
+    # The options are +:table_name+ and +:table_name_with_underscore+. If the first is specified,
+    # the Product class will look for "productid" instead of "id" as the primary column. If the
+    # latter is specified, the Product class will look for "product_id" instead of "id". Remember
+    # that this is a global setting for all Active Records.
+
+    ##
+    # :singleton-method: primary_key_prefix_type=
+    # :call-seq: primary_key_prefix_type=(prefix_type)
+    #
+    # Sets the prefix type that will be prepended to every primary key column name.
+    # The options are +:table_name+ and +:table_name_with_underscore+. If the first is specified,
+    # the Product class will look for "productid" instead of "id" as the primary column. If the
+    # latter is specified, the Product class will look for "product_id" instead of "id". Remember
+    # that this is a global setting for all Active Records.
+
+    ##
+    # :singleton-method: table_name_prefix
+    # :call-seq: table_name_prefix
+    #
+    # The prefix string to prepend to every table name.
+
+    ##
+    # :singleton-method: table_name_prefix=
+    # :call-seq: table_name_prefix=(prefix)
+    #
+    # Sets the prefix string to prepend to every table name. So if set to "basecamp_", all table
+    # names will be named like "basecamp_projects", "basecamp_people", etc. This is a convenient
+    # way of creating a namespace for tables in a shared database. By default, the prefix is the
+    # empty string.
+    #
+    # If you are organising your models within modules you can add a prefix to the models within
+    # a namespace by defining a singleton method in the parent module called table_name_prefix which
+    # returns your chosen prefix.
+
+    ##
+    # :singleton-method: table_name_suffix
+    # :call-seq: table_name_suffix
+    #
+    # The suffix string to append to every table name.
+
+    ##
+    # :singleton-method: table_name_suffix=
+    # :call-seq: table_name_suffix=(suffix)
+    #
+    # Works like +table_name_prefix=+, but appends instead of prepends (set to "_basecamp" gives "projects_basecamp",
+    # "people_basecamp"). By default, the suffix is the empty string.
+    #
+    # If you are organising your models within modules, you can add a suffix to the models within
+    # a namespace by defining a singleton method in the parent module called table_name_suffix which
+    # returns your chosen suffix.
+
+    ##
+    # :singleton-method: schema_migrations_table_name
+    # :call-seq: schema_migrations_table_name
+    #
+    # The name of the schema migrations table. By default, the value is <tt>"schema_migrations"</tt>.
+
+    ##
+    # :singleton-method: schema_migrations_table_name=
+    # :call-seq: schema_migrations_table_name=(table_name)
+    #
+    # Sets the name of the schema migrations table.
+
+    ##
+    # :singleton-method: internal_metadata_table_name
+    # :call-seq: internal_metadata_table_name
+    #
+    # The name of the internal metadata table. By default, the value is <tt>"ar_internal_metadata"</tt>.
+
+    ##
+    # :singleton-method: internal_metadata_table_name=
+    # :call-seq: internal_metadata_table_name=(table_name)
+    #
+    # Sets the name of the internal metadata table.
+
+    ##
+    # :singleton-method: pluralize_table_names
+    # :call-seq: pluralize_table_names
+    #
+    # Indicates whether table names should be the pluralized versions of the corresponding class names.
+    # If true, the default table name for a Product class will be "products". If false, it would just be "product".
+    # See table_name for the full rules on table/class naming. This is true, by default.
+
+    ##
+    # :singleton-method: pluralize_table_names=
+    # :call-seq: pluralize_table_names=(value)
+    #
+    # Set whether table names should be the pluralized versions of the corresponding class names.
+    # If true, the default table name for a Product class will be "products". If false, it would just be "product".
+    # See table_name for the full rules on table/class naming. This is true, by default.
+
     included do
-      ##
-      # :singleton-method:
-      # Accessor for the prefix type that will be prepended to every primary key column name.
-      # The options are :table_name and :table_name_with_underscore. If the first is specified,
-      # the Product class will look for "productid" instead of "id" as the primary column. If the
-      # latter is specified, the Product class will look for "product_id" instead of "id". Remember
-      # that this is a global setting for all Active Records.
       mattr_accessor :primary_key_prefix_type, instance_writer: false
 
-      ##
-      # :singleton-method:
-      # Accessor for the name of the prefix string to prepend to every table name. So if set
-      # to "basecamp_", all table names will be named like "basecamp_projects", "basecamp_people",
-      # etc. This is a convenient way of creating a namespace for tables in a shared database.
-      # By default, the prefix is the empty string.
-      #
-      # If you are organising your models within modules you can add a prefix to the models within
-      # a namespace by defining a singleton method in the parent module called table_name_prefix which
-      # returns your chosen prefix.
-      class_attribute :table_name_prefix, instance_writer: false
-      self.table_name_prefix = ""
-
-      ##
-      # :singleton-method:
-      # Works like +table_name_prefix+, but appends instead of prepends (set to "_basecamp" gives "projects_basecamp",
-      # "people_basecamp"). By default, the suffix is the empty string.
-      #
-      # If you are organising your models within modules, you can add a suffix to the models within
-      # a namespace by defining a singleton method in the parent module called table_name_suffix which
-      # returns your chosen suffix.
-      class_attribute :table_name_suffix, instance_writer: false
-      self.table_name_suffix = ""
-
-      ##
-      # :singleton-method:
-      # Accessor for the name of the schema migrations table. By default, the value is "schema_migrations"
-      class_attribute :schema_migrations_table_name, instance_accessor: false
-      self.schema_migrations_table_name = "schema_migrations"
-
-      ##
-      # :singleton-method:
-      # Accessor for the name of the internal metadata table. By default, the value is "ar_internal_metadata"
-      class_attribute :internal_metadata_table_name, instance_accessor: false
-      self.internal_metadata_table_name = "ar_internal_metadata"
-
-      ##
-      # :singleton-method:
-      # Accessor for an array of names of environments where destructive actions should be prohibited. By default,
-      # the value is ["production"]
-      class_attribute :protected_environments, instance_accessor: false
-      self.protected_environments = ["production"]
+      class_attribute :table_name_prefix, instance_writer: false, default: ""
+      class_attribute :table_name_suffix, instance_writer: false, default: ""
+      class_attribute :schema_migrations_table_name, instance_accessor: false, default: "schema_migrations"
+      class_attribute :internal_metadata_table_name, instance_accessor: false, default: "ar_internal_metadata"
+      class_attribute :pluralize_table_names, instance_writer: false, default: true
 
-      ##
-      # :singleton-method:
-      # Indicates whether table names should be the pluralized versions of the corresponding class names.
-      # If true, the default table name for a Product class will be +products+. If false, it would just be +product+.
-      # See table_name for the full rules on table/class naming. This is true, by default.
-      class_attribute :pluralize_table_names, instance_writer: false
-      self.pluralize_table_names = true
-
-      ##
-      # :singleton-method:
-      # Accessor for the list of columns names the model should ignore. Ignored columns won't have attribute
-      # accessors defined, and won't be referenced in SQL queries.
-      class_attribute :ignored_columns, instance_accessor: false
+      self.protected_environments = ["production"]
+      self.inheritance_column = "type"
       self.ignored_columns = [].freeze
 
-      self.inheritance_column = 'type'
-
       delegate :type_for_attribute, to: :class
+
+      initialize_load_schema_monitor
     end
 
     # Derives the join table name for +first_table+ and +second_table+. The
@@ -173,11 +218,26 @@ module ActiveRecord
       end
 
       def full_table_name_prefix #:nodoc:
-        (parents.detect{ |p| p.respond_to?(:table_name_prefix) } || self).table_name_prefix
+        (parents.detect { |p| p.respond_to?(:table_name_prefix) } || self).table_name_prefix
       end
 
       def full_table_name_suffix #:nodoc:
-        (parents.detect {|p| p.respond_to?(:table_name_suffix) } || self).table_name_suffix
+        (parents.detect { |p| p.respond_to?(:table_name_suffix) } || self).table_name_suffix
+      end
+
+      # The array of names of environments where destructive actions should be prohibited. By default,
+      # the value is <tt>["production"]</tt>.
+      def protected_environments
+        if defined?(@protected_environments)
+          @protected_environments
+        else
+          superclass.protected_environments
+        end
+      end
+
+      # Sets an array of names of environments where destructive actions should be prohibited.
+      def protected_environments=(environments)
+        @protected_environments = environments.map(&:to_s)
       end
 
       # Defines the name of the table column which will store the class name on single-table
@@ -199,6 +259,22 @@ module ActiveRecord
         @explicit_inheritance_column = true
       end
 
+      # The list of columns names the model should ignore. Ignored columns won't have attribute
+      # accessors defined, and won't be referenced in SQL queries.
+      def ignored_columns
+        if defined?(@ignored_columns)
+          @ignored_columns
+        else
+          superclass.ignored_columns
+        end
+      end
+
+      # Sets the columns names the model should ignore. Ignored columns won't have attribute
+      # accessors defined, and won't be referenced in SQL queries.
+      def ignored_columns=(columns)
+        @ignored_columns = columns.map(&:to_s)
+      end
+
       def sequence_name
         if base_class == self
           @sequence_name ||= reset_sequence_name
@@ -213,7 +289,7 @@ module ActiveRecord
       end
 
       # Sets the name of the sequence to use when generating ids to the given
-      # value, or (if the value is nil or false) to the value returned by the
+      # value, or (if the value is +nil+ or +false+) to the value returned by the
       # given block. This is required for Oracle and is useful for any
       # database which relies on sequences for primary key generation.
       #
@@ -249,7 +325,11 @@ module ActiveRecord
       end
 
       def attributes_builder # :nodoc:
-        @attributes_builder ||= AttributeSet::Builder.new(attribute_types, primary_key)
+        unless defined?(@attributes_builder) && @attributes_builder
+          defaults = _default_attributes.except(*(column_names - [primary_key]))
+          @attributes_builder = ActiveModel::AttributeSet::Builder.new(attribute_types, defaults)
+        end
+        @attributes_builder
       end
 
       def columns_hash # :nodoc:
@@ -264,11 +344,11 @@ module ActiveRecord
 
       def attribute_types # :nodoc:
         load_schema
-        @attribute_types ||= Hash.new(Type::Value.new)
+        @attribute_types ||= Hash.new(Type.default_value)
       end
 
       def yaml_encoder # :nodoc:
-        @yaml_encoder ||= AttributeSet::YAMLEncoder.new(attribute_types)
+        @yaml_encoder ||= ActiveModel::AttributeSet::YAMLEncoder.new(attribute_types)
       end
 
       # Returns the type of the attribute with the given name, after applying
@@ -282,19 +362,23 @@ module ActiveRecord
       #
       # +attr_name+ The name of the attribute to retrieve the type for. Must be
       # a string
-      def type_for_attribute(attr_name)
-        attribute_types[attr_name]
+      def type_for_attribute(attr_name, &block)
+        if block
+          attribute_types.fetch(attr_name, &block)
+        else
+          attribute_types[attr_name]
+        end
       end
 
       # Returns a hash where the keys are column names and the values are
       # default values when instantiating the Active Record object for this table.
       def column_defaults
         load_schema
-        _default_attributes.to_hash
+        @column_defaults ||= _default_attributes.to_hash
       end
 
       def _default_attributes # :nodoc:
-        @default_attributes ||= AttributeSet.new({})
+        @default_attributes ||= ActiveModel::AttributeSet.new({})
       end
 
       # Returns an array of column names as strings.
@@ -305,7 +389,12 @@ module ActiveRecord
       # Returns an array of column objects where the primary id, all columns ending in "_id" or "_count",
       # and columns used for single table inheritance have been removed.
       def content_columns
-        @content_columns ||= columns.reject { |c| c.name == primary_key || c.name =~ /(_id|_count)$/ || c.name == inheritance_column }
+        @content_columns ||= columns.reject do |c|
+          c.name == primary_key ||
+          c.name == inheritance_column ||
+          c.name.end_with?("_id") ||
+          c.name.end_with?("_count")
+        end
       end
 
       # Resets all the cached information about columns, which will cause them
@@ -336,100 +425,95 @@ module ActiveRecord
       #  end
       def reset_column_information
         connection.clear_cache!
-        undefine_attribute_methods
+        ([self] + descendants).each(&:undefine_attribute_methods)
         connection.schema_cache.clear_data_source_cache!(table_name)
 
         reload_schema_from_cache
+        initialize_find_by_cache
       end
 
-      private
-
-      def schema_loaded?
-        defined?(@columns_hash) && @columns_hash
-      end
+      protected
 
-      def load_schema
-        unless schema_loaded?
-          load_schema!
+        def initialize_load_schema_monitor
+          @load_schema_monitor = Monitor.new
         end
-      end
 
-      def load_schema!
-        @columns_hash = connection.schema_cache.columns_hash(table_name).except(*ignored_columns)
-        @columns_hash.each do |name, column|
-          warn_if_deprecated_type(column)
-          define_attribute(
-            name,
-            connection.lookup_cast_type_from_column(column),
-            default: column.default,
-            user_provided_default: false
-          )
+      private
+
+        def inherited(child_class)
+          super
+          child_class.initialize_load_schema_monitor
         end
-      end
 
-      def reload_schema_from_cache
-        @arel_engine = nil
-        @arel_table = nil
-        @column_names = nil
-        @attribute_types = nil
-        @content_columns = nil
-        @default_attributes = nil
-        @inheritance_column = nil unless defined?(@explicit_inheritance_column) && @explicit_inheritance_column
-        @attributes_builder = nil
-        @columns = nil
-        @columns_hash = nil
-        @attribute_names = nil
-        @yaml_encoder = nil
-        direct_descendants.each do |descendant|
-          descendant.send(:reload_schema_from_cache)
+        def schema_loaded?
+          defined?(@schema_loaded) && @schema_loaded
         end
-      end
 
-      # Guesses the table name, but does not decorate it with prefix and suffix information.
-      def undecorated_table_name(class_name = base_class.name)
-        table_name = class_name.to_s.demodulize.underscore
-        pluralize_table_names ? table_name.pluralize : table_name
-      end
+        def load_schema
+          return if schema_loaded?
+          @load_schema_monitor.synchronize do
+            return if defined?(@columns_hash) && @columns_hash
 
-      # Computes and returns a table name according to default conventions.
-      def compute_table_name
-        base = base_class
-        if self == base
-          # Nested classes are prefixed with singular parent table name.
-          if parent < Base && !parent.abstract_class?
-            contained = parent.table_name
-            contained = contained.singularize if parent.pluralize_table_names
-            contained += '_'
-          end
+            load_schema!
 
-          "#{full_table_name_prefix}#{contained}#{undecorated_table_name(name)}#{full_table_name_suffix}"
-        else
-          # STI subclasses always use their superclass' table.
-          base.table_name
+            @schema_loaded = true
+          end
         end
-      end
 
-      def warn_if_deprecated_type(column)
-        return if attributes_to_define_after_schema_loads.key?(column.name)
-        if column.respond_to?(:oid) && column.sql_type.start_with?("point")
-          if column.array?
-            array_arguments = ", array: true"
-          else
-            array_arguments = ""
+        def load_schema!
+          @columns_hash = connection.schema_cache.columns_hash(table_name).except(*ignored_columns)
+          @columns_hash.each do |name, column|
+            define_attribute(
+              name,
+              connection.lookup_cast_type_from_column(column),
+              default: column.default,
+              user_provided_default: false
+            )
           end
-          ActiveSupport::Deprecation.warn(<<-WARNING.strip_heredoc)
-            The behavior of the `:point` type will be changing in Rails 5.1 to
-            return a `Point` object, rather than an `Array`. If you'd like to
-            keep the old behavior, you can add this line to #{self.name}:
+        end
 
-              attribute :#{column.name}, :legacy_point#{array_arguments}
+        def reload_schema_from_cache
+          @arel_table = nil
+          @column_names = nil
+          @attribute_types = nil
+          @content_columns = nil
+          @default_attributes = nil
+          @column_defaults = nil
+          @inheritance_column = nil unless defined?(@explicit_inheritance_column) && @explicit_inheritance_column
+          @attributes_builder = nil
+          @columns = nil
+          @columns_hash = nil
+          @schema_loaded = false
+          @attribute_names = nil
+          @yaml_encoder = nil
+          direct_descendants.each do |descendant|
+            descendant.send(:reload_schema_from_cache)
+          end
+        end
 
-            If you'd like the new behavior today, you can add this line:
+        # Guesses the table name, but does not decorate it with prefix and suffix information.
+        def undecorated_table_name(class_name = base_class.name)
+          table_name = class_name.to_s.demodulize.underscore
+          pluralize_table_names ? table_name.pluralize : table_name
+        end
 
-              attribute :#{column.name}, :point#{array_arguments}
-          WARNING
+        # Computes and returns a table name according to default conventions.
+        def compute_table_name
+          base = base_class
+          if self == base
+            # Nested classes are prefixed with singular parent table name.
+            if parent < Base && !parent.abstract_class?
+              contained = parent.table_name
+              contained = contained.singularize if parent.pluralize_table_names
+              contained += "_"
+            end
+
+            "#{full_table_name_prefix}#{contained}#{undecorated_table_name(name)}#{full_table_name_suffix}"
+          else
+            # STI subclasses always use their superclass' table.
+            base.table_name
+          end
         end
-      end
     end
   end
 end
diff --git a/activerecord/lib/active_record/nested_attributes.rb b/activerecord/lib/active_record/nested_attributes.rb
index fe68869143..fa20bce3a9 100644
--- a/activerecord/lib/active_record/nested_attributes.rb
+++ b/activerecord/lib/active_record/nested_attributes.rb
@@ -1,6 +1,9 @@
-require 'active_support/core_ext/hash/except'
-require 'active_support/core_ext/object/try'
-require 'active_support/core_ext/hash/indifferent_access'
+# frozen_string_literal: true
+
+require "active_support/core_ext/hash/except"
+require "active_support/core_ext/module/redefine_method"
+require "active_support/core_ext/object/try"
+require "active_support/core_ext/hash/indifferent_access"
 
 module ActiveRecord
   module NestedAttributes #:nodoc:
@@ -10,8 +13,7 @@ module ActiveRecord
     extend ActiveSupport::Concern
 
     included do
-      class_attribute :nested_attributes_options, instance_writer: false
-      self.nested_attributes_options = {}
+      class_attribute :nested_attributes_options, instance_writer: false, default: {}
     end
 
     # = Active Record Nested Attributes
@@ -61,6 +63,18 @@ module ActiveRecord
     #   member.update params[:member]
     #   member.avatar.icon # => 'sad'
     #
+    # If you want to update the current avatar without providing the id, you must add <tt>:update_only</tt> option.
+    #
+    #   class Member < ActiveRecord::Base
+    #     has_one :avatar
+    #     accepts_nested_attributes_for :avatar, update_only: true
+    #   end
+    #
+    #   params = { member: { avatar_attributes: { icon: 'sad' } } }
+    #   member.update params[:member]
+    #   member.avatar.id # => 2
+    #   member.avatar.icon # => 'sad'
+    #
     # By default you will only be able to set and update attributes on the
     # associated model. If you want to destroy the associated model through the
     # attributes hash, you have to enable it first using the
@@ -267,7 +281,7 @@ module ActiveRecord
     #   member.avatar_attributes = {icon: 'sad'}
     #   member.avatar.width # => 200
     module ClassMethods
-      REJECT_ALL_BLANK_PROC = proc { |attributes| attributes.all? { |key, value| key == '_destroy' || value.blank? } }
+      REJECT_ALL_BLANK_PROC = proc { |attributes| attributes.all? { |key, value| key == "_destroy" || value.blank? } }
 
       # Defines an attributes writer for the specified association(s).
       #
@@ -317,7 +331,7 @@ module ActiveRecord
       #   # creates avatar_attributes= and posts_attributes=
       #   accepts_nested_attributes_for :avatar, :posts, allow_destroy: true
       def accepts_nested_attributes_for(*attr_names)
-        options = { :allow_destroy => false, :update_only => false }
+        options = { allow_destroy: false, update_only: false }
         options.update(attr_names.extract_options!)
         options.assert_valid_keys(:allow_destroy, :reject_if, :limit, :update_only)
         options[:reject_if] = REJECT_ALL_BLANK_PROC if options[:reject_if] == :all_blank
@@ -341,27 +355,25 @@ module ActiveRecord
 
       private
 
-      # Generates a writer method for this association. Serves as a point for
-      # accessing the objects in the association. For example, this method
-      # could generate the following:
-      #
-      #   def pirate_attributes=(attributes)
-      #     assign_nested_attributes_for_one_to_one_association(:pirate, attributes)
-      #   end
-      #
-      # This redirects the attempts to write objects in an association through
-      # the helper methods defined below. Makes it seem like the nested
-      # associations are just regular associations.
-      def generate_association_writer(association_name, type)
-        generated_association_methods.module_eval <<-eoruby, __FILE__, __LINE__ + 1
-          if method_defined?(:#{association_name}_attributes=)
-            remove_method(:#{association_name}_attributes=)
-          end
-          def #{association_name}_attributes=(attributes)
-            assign_nested_attributes_for_#{type}_association(:#{association_name}, attributes)
-          end
-        eoruby
-      end
+        # Generates a writer method for this association. Serves as a point for
+        # accessing the objects in the association. For example, this method
+        # could generate the following:
+        #
+        #   def pirate_attributes=(attributes)
+        #     assign_nested_attributes_for_one_to_one_association(:pirate, attributes)
+        #   end
+        #
+        # This redirects the attempts to write objects in an association through
+        # the helper methods defined below. Makes it seem like the nested
+        # associations are just regular associations.
+        def generate_association_writer(association_name, type)
+          generated_association_methods.module_eval <<-eoruby, __FILE__, __LINE__ + 1
+            silence_redefinition_of_method :#{association_name}_attributes=
+            def #{association_name}_attributes=(attributes)
+              assign_nested_attributes_for_#{type}_association(:#{association_name}, attributes)
+            end
+          eoruby
+        end
     end
 
     # Returns ActiveRecord::AutosaveAssociation::marked_for_destruction? It's
@@ -375,213 +387,214 @@ module ActiveRecord
 
     private
 
-    # Attribute hash keys that should not be assigned as normal attributes.
-    # These hash keys are nested attributes implementation details.
-    UNASSIGNABLE_KEYS = %w( id _destroy )
-
-    # Assigns the given attributes to the association.
-    #
-    # If an associated record does not yet exist, one will be instantiated. If
-    # an associated record already exists, the method's behavior depends on
-    # the value of the update_only option. If update_only is +false+ and the
-    # given attributes include an <tt>:id</tt> that matches the existing record's
-    # id, then the existing record will be modified. If no <tt>:id</tt> is provided
-    # it will be replaced with a new record. If update_only is +true+ the existing
-    # record will be modified regardless of whether an <tt>:id</tt> is provided.
-    #
-    # If the given attributes include a matching <tt>:id</tt> attribute, or
-    # update_only is true, and a <tt>:_destroy</tt> key set to a truthy value,
-    # then the existing record will be marked for destruction.
-    def assign_nested_attributes_for_one_to_one_association(association_name, attributes)
-      options = self.nested_attributes_options[association_name]
-      if attributes.respond_to?(:permitted?)
-        attributes = attributes.to_h
-      end
-      attributes = attributes.with_indifferent_access
-      existing_record = send(association_name)
+      # Attribute hash keys that should not be assigned as normal attributes.
+      # These hash keys are nested attributes implementation details.
+      UNASSIGNABLE_KEYS = %w( id _destroy )
+
+      # Assigns the given attributes to the association.
+      #
+      # If an associated record does not yet exist, one will be instantiated. If
+      # an associated record already exists, the method's behavior depends on
+      # the value of the update_only option. If update_only is +false+ and the
+      # given attributes include an <tt>:id</tt> that matches the existing record's
+      # id, then the existing record will be modified. If no <tt>:id</tt> is provided
+      # it will be replaced with a new record. If update_only is +true+ the existing
+      # record will be modified regardless of whether an <tt>:id</tt> is provided.
+      #
+      # If the given attributes include a matching <tt>:id</tt> attribute, or
+      # update_only is true, and a <tt>:_destroy</tt> key set to a truthy value,
+      # then the existing record will be marked for destruction.
+      def assign_nested_attributes_for_one_to_one_association(association_name, attributes)
+        options = nested_attributes_options[association_name]
+        if attributes.respond_to?(:permitted?)
+          attributes = attributes.to_h
+        end
+        attributes = attributes.with_indifferent_access
+        existing_record = send(association_name)
 
-      if (options[:update_only] || !attributes['id'].blank?) && existing_record &&
-          (options[:update_only] || existing_record.id.to_s == attributes['id'].to_s)
-        assign_to_or_mark_for_destruction(existing_record, attributes, options[:allow_destroy]) unless call_reject_if(association_name, attributes)
+        if (options[:update_only] || !attributes["id"].blank?) && existing_record &&
+            (options[:update_only] || existing_record.id.to_s == attributes["id"].to_s)
+          assign_to_or_mark_for_destruction(existing_record, attributes, options[:allow_destroy]) unless call_reject_if(association_name, attributes)
 
-      elsif attributes['id'].present?
-        raise_nested_attributes_record_not_found!(association_name, attributes['id'])
+        elsif attributes["id"].present?
+          raise_nested_attributes_record_not_found!(association_name, attributes["id"])
 
-      elsif !reject_new_record?(association_name, attributes)
-        assignable_attributes = attributes.except(*UNASSIGNABLE_KEYS)
+        elsif !reject_new_record?(association_name, attributes)
+          assignable_attributes = attributes.except(*UNASSIGNABLE_KEYS)
 
-        if existing_record && existing_record.new_record?
-          existing_record.assign_attributes(assignable_attributes)
-          association(association_name).initialize_attributes(existing_record)
-        else
-          method = "build_#{association_name}"
-          if respond_to?(method)
-            send(method, assignable_attributes)
+          if existing_record && existing_record.new_record?
+            existing_record.assign_attributes(assignable_attributes)
+            association(association_name).initialize_attributes(existing_record)
           else
-            raise ArgumentError, "Cannot build association `#{association_name}'. Are you trying to build a polymorphic one-to-one association?"
+            method = "build_#{association_name}"
+            if respond_to?(method)
+              send(method, assignable_attributes)
+            else
+              raise ArgumentError, "Cannot build association `#{association_name}'. Are you trying to build a polymorphic one-to-one association?"
+            end
           end
         end
       end
-    end
 
-    # Assigns the given attributes to the collection association.
-    #
-    # Hashes with an <tt>:id</tt> value matching an existing associated record
-    # will update that record. Hashes without an <tt>:id</tt> value will build
-    # a new record for the association. Hashes with a matching <tt>:id</tt>
-    # value and a <tt>:_destroy</tt> key set to a truthy value will mark the
-    # matched record for destruction.
-    #
-    # For example:
-    #
-    #   assign_nested_attributes_for_collection_association(:people, {
-    #     '1' => { id: '1', name: 'Peter' },
-    #     '2' => { name: 'John' },
-    #     '3' => { id: '2', _destroy: true }
-    #   })
-    #
-    # Will update the name of the Person with ID 1, build a new associated
-    # person with the name 'John', and mark the associated Person with ID 2
-    # for destruction.
-    #
-    # Also accepts an Array of attribute hashes:
-    #
-    #   assign_nested_attributes_for_collection_association(:people, [
-    #     { id: '1', name: 'Peter' },
-    #     { name: 'John' },
-    #     { id: '2', _destroy: true }
-    #   ])
-    def assign_nested_attributes_for_collection_association(association_name, attributes_collection)
-      options = self.nested_attributes_options[association_name]
-      if attributes_collection.respond_to?(:permitted?)
-        attributes_collection = attributes_collection.to_h
-      end
+      # Assigns the given attributes to the collection association.
+      #
+      # Hashes with an <tt>:id</tt> value matching an existing associated record
+      # will update that record. Hashes without an <tt>:id</tt> value will build
+      # a new record for the association. Hashes with a matching <tt>:id</tt>
+      # value and a <tt>:_destroy</tt> key set to a truthy value will mark the
+      # matched record for destruction.
+      #
+      # For example:
+      #
+      #   assign_nested_attributes_for_collection_association(:people, {
+      #     '1' => { id: '1', name: 'Peter' },
+      #     '2' => { name: 'John' },
+      #     '3' => { id: '2', _destroy: true }
+      #   })
+      #
+      # Will update the name of the Person with ID 1, build a new associated
+      # person with the name 'John', and mark the associated Person with ID 2
+      # for destruction.
+      #
+      # Also accepts an Array of attribute hashes:
+      #
+      #   assign_nested_attributes_for_collection_association(:people, [
+      #     { id: '1', name: 'Peter' },
+      #     { name: 'John' },
+      #     { id: '2', _destroy: true }
+      #   ])
+      def assign_nested_attributes_for_collection_association(association_name, attributes_collection)
+        options = nested_attributes_options[association_name]
+        if attributes_collection.respond_to?(:permitted?)
+          attributes_collection = attributes_collection.to_h
+        end
 
-      unless attributes_collection.is_a?(Hash) || attributes_collection.is_a?(Array)
-        raise ArgumentError, "Hash or Array expected, got #{attributes_collection.class.name} (#{attributes_collection.inspect})"
-      end
+        unless attributes_collection.is_a?(Hash) || attributes_collection.is_a?(Array)
+          raise ArgumentError, "Hash or Array expected for attribute `#{association_name}`, got #{attributes_collection.class.name} (#{attributes_collection.inspect})"
+        end
 
-      check_record_limit!(options[:limit], attributes_collection)
+        check_record_limit!(options[:limit], attributes_collection)
 
-      if attributes_collection.is_a? Hash
-        keys = attributes_collection.keys
-        attributes_collection = if keys.include?('id') || keys.include?(:id)
-          [attributes_collection]
-        else
-          attributes_collection.values
+        if attributes_collection.is_a? Hash
+          keys = attributes_collection.keys
+          attributes_collection = if keys.include?("id") || keys.include?(:id)
+            [attributes_collection]
+          else
+            attributes_collection.values
+          end
         end
-      end
-
-      association = association(association_name)
 
-      existing_records = if association.loaded?
-        association.target
-      else
-        attribute_ids = attributes_collection.map {|a| a['id'] || a[:id] }.compact
-        attribute_ids.empty? ? [] : association.scope.where(association.klass.primary_key => attribute_ids)
-      end
+        association = association(association_name)
 
-      attributes_collection.each do |attributes|
-        if attributes.respond_to?(:permitted?)
-          attributes = attributes.to_h
+        existing_records = if association.loaded?
+          association.target
+        else
+          attribute_ids = attributes_collection.map { |a| a["id"] || a[:id] }.compact
+          attribute_ids.empty? ? [] : association.scope.where(association.klass.primary_key => attribute_ids)
         end
-        attributes = attributes.with_indifferent_access
 
-        if attributes['id'].blank?
-          unless reject_new_record?(association_name, attributes)
-            association.build(attributes.except(*UNASSIGNABLE_KEYS))
+        attributes_collection.each do |attributes|
+          if attributes.respond_to?(:permitted?)
+            attributes = attributes.to_h
           end
-        elsif existing_record = existing_records.detect { |record| record.id.to_s == attributes['id'].to_s }
-          unless call_reject_if(association_name, attributes)
-            # Make sure we are operating on the actual object which is in the association's
-            # proxy_target array (either by finding it, or adding it if not found)
-            # Take into account that the proxy_target may have changed due to callbacks
-            target_record = association.target.detect { |record| record.id.to_s == attributes['id'].to_s }
-            if target_record
-              existing_record = target_record
-            else
-              association.add_to_target(existing_record, :skip_callbacks)
-            end
+          attributes = attributes.with_indifferent_access
 
-            assign_to_or_mark_for_destruction(existing_record, attributes, options[:allow_destroy])
+          if attributes["id"].blank?
+            unless reject_new_record?(association_name, attributes)
+              association.build(attributes.except(*UNASSIGNABLE_KEYS))
+            end
+          elsif existing_record = existing_records.detect { |record| record.id.to_s == attributes["id"].to_s }
+            unless call_reject_if(association_name, attributes)
+              # Make sure we are operating on the actual object which is in the association's
+              # proxy_target array (either by finding it, or adding it if not found)
+              # Take into account that the proxy_target may have changed due to callbacks
+              target_record = association.target.detect { |record| record.id.to_s == attributes["id"].to_s }
+              if target_record
+                existing_record = target_record
+              else
+                association.add_to_target(existing_record, :skip_callbacks)
+              end
+
+              assign_to_or_mark_for_destruction(existing_record, attributes, options[:allow_destroy])
+            end
+          else
+            raise_nested_attributes_record_not_found!(association_name, attributes["id"])
           end
-        else
-          raise_nested_attributes_record_not_found!(association_name, attributes['id'])
         end
       end
-    end
 
-    # Takes in a limit and checks if the attributes_collection has too many
-    # records. It accepts limit in the form of symbol, proc, or
-    # number-like object (anything that can be compared with an integer).
-    #
-    # Raises TooManyRecords error if the attributes_collection is
-    # larger than the limit.
-    def check_record_limit!(limit, attributes_collection)
-      if limit
-        limit = case limit
-        when Symbol
-          send(limit)
-        when Proc
-          limit.call
-        else
-          limit
-        end
+      # Takes in a limit and checks if the attributes_collection has too many
+      # records. It accepts limit in the form of symbol, proc, or
+      # number-like object (anything that can be compared with an integer).
+      #
+      # Raises TooManyRecords error if the attributes_collection is
+      # larger than the limit.
+      def check_record_limit!(limit, attributes_collection)
+        if limit
+          limit = \
+            case limit
+            when Symbol
+              send(limit)
+            when Proc
+              limit.call
+            else
+              limit
+            end
 
-        if limit && attributes_collection.size > limit
-          raise TooManyRecords, "Maximum #{limit} records are allowed. Got #{attributes_collection.size} records instead."
+          if limit && attributes_collection.size > limit
+            raise TooManyRecords, "Maximum #{limit} records are allowed. Got #{attributes_collection.size} records instead."
+          end
         end
       end
-    end
 
-    # Updates a record with the +attributes+ or marks it for destruction if
-    # +allow_destroy+ is +true+ and has_destroy_flag? returns +true+.
-    def assign_to_or_mark_for_destruction(record, attributes, allow_destroy)
-      record.assign_attributes(attributes.except(*UNASSIGNABLE_KEYS))
-      record.mark_for_destruction if has_destroy_flag?(attributes) && allow_destroy
-    end
+      # Updates a record with the +attributes+ or marks it for destruction if
+      # +allow_destroy+ is +true+ and has_destroy_flag? returns +true+.
+      def assign_to_or_mark_for_destruction(record, attributes, allow_destroy)
+        record.assign_attributes(attributes.except(*UNASSIGNABLE_KEYS))
+        record.mark_for_destruction if has_destroy_flag?(attributes) && allow_destroy
+      end
 
-    # Determines if a hash contains a truthy _destroy key.
-    def has_destroy_flag?(hash)
-      Type::Boolean.new.cast(hash['_destroy'])
-    end
+      # Determines if a hash contains a truthy _destroy key.
+      def has_destroy_flag?(hash)
+        Type::Boolean.new.cast(hash["_destroy"])
+      end
 
-    # Determines if a new record should be rejected by checking
-    # has_destroy_flag? or if a <tt>:reject_if</tt> proc exists for this
-    # association and evaluates to +true+.
-    def reject_new_record?(association_name, attributes)
-      will_be_destroyed?(association_name, attributes) || call_reject_if(association_name, attributes)
-    end
+      # Determines if a new record should be rejected by checking
+      # has_destroy_flag? or if a <tt>:reject_if</tt> proc exists for this
+      # association and evaluates to +true+.
+      def reject_new_record?(association_name, attributes)
+        will_be_destroyed?(association_name, attributes) || call_reject_if(association_name, attributes)
+      end
 
-    # Determines if a record with the particular +attributes+ should be
-    # rejected by calling the reject_if Symbol or Proc (if defined).
-    # The reject_if option is defined by +accepts_nested_attributes_for+.
-    #
-    # Returns false if there is a +destroy_flag+ on the attributes.
-    def call_reject_if(association_name, attributes)
-      return false if will_be_destroyed?(association_name, attributes)
+      # Determines if a record with the particular +attributes+ should be
+      # rejected by calling the reject_if Symbol or Proc (if defined).
+      # The reject_if option is defined by +accepts_nested_attributes_for+.
+      #
+      # Returns false if there is a +destroy_flag+ on the attributes.
+      def call_reject_if(association_name, attributes)
+        return false if will_be_destroyed?(association_name, attributes)
 
-      case callback = self.nested_attributes_options[association_name][:reject_if]
-      when Symbol
-        method(callback).arity == 0 ? send(callback) : send(callback, attributes)
-      when Proc
-        callback.call(attributes)
+        case callback = nested_attributes_options[association_name][:reject_if]
+        when Symbol
+          method(callback).arity == 0 ? send(callback) : send(callback, attributes)
+        when Proc
+          callback.call(attributes)
+        end
       end
-    end
 
-    # Only take into account the destroy flag if <tt>:allow_destroy</tt> is true
-    def will_be_destroyed?(association_name, attributes)
-      allow_destroy?(association_name) && has_destroy_flag?(attributes)
-    end
+      # Only take into account the destroy flag if <tt>:allow_destroy</tt> is true
+      def will_be_destroyed?(association_name, attributes)
+        allow_destroy?(association_name) && has_destroy_flag?(attributes)
+      end
 
-    def allow_destroy?(association_name)
-      self.nested_attributes_options[association_name][:allow_destroy]
-    end
+      def allow_destroy?(association_name)
+        nested_attributes_options[association_name][:allow_destroy]
+      end
 
-    def raise_nested_attributes_record_not_found!(association_name, record_id)
-      model = self.class._reflect_on_association(association_name).klass.name
-      raise RecordNotFound.new("Couldn't find #{model} with ID=#{record_id} for #{self.class.name} with ID=#{id}",
-                               model, 'id', record_id)
-    end
+      def raise_nested_attributes_record_not_found!(association_name, record_id)
+        model = self.class._reflect_on_association(association_name).klass.name
+        raise RecordNotFound.new("Couldn't find #{model} with ID=#{record_id} for #{self.class.name} with ID=#{id}",
+                                 model, "id", record_id)
+      end
   end
 end
diff --git a/activerecord/lib/active_record/no_touching.rb b/activerecord/lib/active_record/no_touching.rb
index edb5066fa0..754c891884 100644
--- a/activerecord/lib/active_record/no_touching.rb
+++ b/activerecord/lib/active_record/no_touching.rb
@@ -1,10 +1,12 @@
+# frozen_string_literal: true
+
 module ActiveRecord
   # = Active Record No Touching
   module NoTouching
     extend ActiveSupport::Concern
 
     module ClassMethods
-      # Lets you selectively disable calls to `touch` for the
+      # Lets you selectively disable calls to +touch+ for the
       # duration of a block.
       #
       # ==== Examples
@@ -45,6 +47,10 @@ module ActiveRecord
       NoTouching.applied_to?(self.class)
     end
 
+    def touch_later(*) # :nodoc:
+      super unless no_touching?
+    end
+
     def touch(*) # :nodoc:
       super unless no_touching?
     end
diff --git a/activerecord/lib/active_record/null_relation.rb b/activerecord/lib/active_record/null_relation.rb
index 1ab4e0404f..cf0de0fdeb 100644
--- a/activerecord/lib/active_record/null_relation.rb
+++ b/activerecord/lib/active_record/null_relation.rb
@@ -1,14 +1,12 @@
+# frozen_string_literal: true
+
 module ActiveRecord
   module NullRelation # :nodoc:
-    def exec_queries
-      @records = [].freeze
-    end
-
     def pluck(*column_names)
       []
     end
 
-    def delete_all(_conditions = nil)
+    def delete_all
       0
     end
 
@@ -20,10 +18,6 @@ module ActiveRecord
       0
     end
 
-    def size
-      calculate :size, nil
-    end
-
     def empty?
       true
     end
@@ -48,33 +42,12 @@ module ActiveRecord
       ""
     end
 
-    def count(*)
-      calculate :count, nil
-    end
-
-    def sum(*)
-      calculate :sum, nil
-    end
-
-    def average(*)
-      calculate :average, nil
-    end
-
-    def minimum(*)
-      calculate :minimum, nil
-    end
-
-    def maximum(*)
-      calculate :maximum, nil
-    end
-
     def calculate(operation, _column_name)
-      if [:count, :sum, :size].include? operation
+      case operation
+      when :count, :sum
         group_values.any? ? Hash.new : 0
-      elsif [:average, :minimum, :maximum].include?(operation) && group_values.any?
-        Hash.new
-      else
-        nil
+      when :average, :minimum, :maximum
+        group_values.any? ? Hash.new : nil
       end
     end
 
@@ -85,5 +58,11 @@ module ActiveRecord
     def or(other)
       other.spawn
     end
+
+    private
+
+      def exec_queries
+        @records = [].freeze
+      end
   end
 end
diff --git a/activerecord/lib/active_record/persistence.rb b/activerecord/lib/active_record/persistence.rb
index afed5e5e85..462e5e7aaf 100644
--- a/activerecord/lib/active_record/persistence.rb
+++ b/activerecord/lib/active_record/persistence.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActiveRecord
   # = Active Record \Persistence
   module Persistence
@@ -63,10 +65,136 @@ module ActiveRecord
       #
       # See <tt>ActiveRecord::Inheritance#discriminate_class_for_record</tt> to see
       # how this "single-table" inheritance mapping is implemented.
-      def instantiate(attributes, column_types = {})
+      def instantiate(attributes, column_types = {}, &block)
         klass = discriminate_class_for_record(attributes)
         attributes = klass.attributes_builder.build_from_database(attributes, column_types)
-        klass.allocate.init_with('attributes' => attributes, 'new_record' => false)
+        klass.allocate.init_with("attributes" => attributes, "new_record" => false, &block)
+      end
+
+      # Updates an object (or multiple objects) and saves it to the database, if validations pass.
+      # The resulting object is returned whether the object was saved successfully to the database or not.
+      #
+      # ==== Parameters
+      #
+      # * +id+ - This should be the id or an array of ids to be updated.
+      # * +attributes+ - This should be a hash of attributes or an array of hashes.
+      #
+      # ==== Examples
+      #
+      #   # Updates one record
+      #   Person.update(15, user_name: "Samuel", group: "expert")
+      #
+      #   # Updates multiple records
+      #   people = { 1 => { "first_name" => "David" }, 2 => { "first_name" => "Jeremy" } }
+      #   Person.update(people.keys, people.values)
+      #
+      #   # Updates multiple records from the result of a relation
+      #   people = Person.where(group: "expert")
+      #   people.update(group: "masters")
+      #
+      # Note: Updating a large number of records will run an UPDATE
+      # query for each record, which may cause a performance issue.
+      # When running callbacks is not needed for each record update,
+      # it is preferred to use {update_all}[rdoc-ref:Relation#update_all]
+      # for updating all records in a single query.
+      def update(id = :all, attributes)
+        if id.is_a?(Array)
+          id.map { |one_id| find(one_id) }.each_with_index { |object, idx|
+            object.update(attributes[idx])
+          }
+        elsif id == :all
+          all.each { |record| record.update(attributes) }
+        else
+          if ActiveRecord::Base === id
+            raise ArgumentError,
+              "You are passing an instance of ActiveRecord::Base to `update`. " \
+              "Please pass the id of the object by calling `.id`."
+          end
+          object = find(id)
+          object.update(attributes)
+          object
+        end
+      end
+
+      # Destroy an object (or multiple objects) that has the given id. The object is instantiated first,
+      # therefore all callbacks and filters are fired off before the object is deleted. This method is
+      # less efficient than #delete but allows cleanup methods and other actions to be run.
+      #
+      # This essentially finds the object (or multiple objects) with the given id, creates a new object
+      # from the attributes, and then calls destroy on it.
+      #
+      # ==== Parameters
+      #
+      # * +id+ - This should be the id or an array of ids to be destroyed.
+      #
+      # ==== Examples
+      #
+      #   # Destroy a single object
+      #   Todo.destroy(1)
+      #
+      #   # Destroy multiple objects
+      #   todos = [1,2,3]
+      #   Todo.destroy(todos)
+      def destroy(id)
+        if id.is_a?(Array)
+          find(id).each(&:destroy)
+        else
+          find(id).destroy
+        end
+      end
+
+      # Deletes the row with a primary key matching the +id+ argument, using a
+      # SQL +DELETE+ statement, and returns the number of rows deleted. Active
+      # Record objects are not instantiated, so the object's callbacks are not
+      # executed, including any <tt>:dependent</tt> association options.
+      #
+      # You can delete multiple rows at once by passing an Array of <tt>id</tt>s.
+      #
+      # Note: Although it is often much faster than the alternative, #destroy,
+      # skipping callbacks might bypass business logic in your application
+      # that ensures referential integrity or performs other essential jobs.
+      #
+      # ==== Examples
+      #
+      #   # Delete a single row
+      #   Todo.delete(1)
+      #
+      #   # Delete multiple rows
+      #   Todo.delete([2,3,4])
+      def delete(id_or_array)
+        where(primary_key => id_or_array).delete_all
+      end
+
+      def _insert_record(values) # :nodoc:
+        primary_key_value = nil
+
+        if primary_key && Hash === values
+          arel_primary_key = arel_attribute(primary_key)
+          primary_key_value = values[arel_primary_key]
+
+          if !primary_key_value && prefetch_primary_key?
+            primary_key_value = next_sequence_value
+            values[arel_primary_key] = primary_key_value
+          end
+        end
+
+        if values.empty?
+          im = arel_table.compile_insert(connection.empty_insert_statement_value)
+          im.into arel_table
+        else
+          im = arel_table.compile_insert(_substitute_values(values))
+        end
+
+        connection.insert(im, "#{self} Create", primary_key || false, primary_key_value)
+      end
+
+      def _update_record(values, id, id_was) # :nodoc:
+        bind = predicate_builder.build_bind_attribute(primary_key, id_was || id)
+        um = arel_table.where(
+          arel_attribute(primary_key).eq(bind)
+        ).compile_update(_substitute_values(values), primary_key)
+
+        connection.update(um, "#{self} Update")
       end
 
       private
@@ -78,6 +206,13 @@ module ActiveRecord
         def discriminate_class_for_record(record)
           self
         end
+
+        def _substitute_values(values)
+          values.map do |attr, value|
+            bind = predicate_builder.build_bind_attribute(attr.name, value)
+            [attr, bind]
+          end
+        end
     end
 
     # Returns true if this object hasn't been saved yet -- that is, a record
@@ -100,6 +235,10 @@ module ActiveRecord
       !(@new_record || @destroyed)
     end
 
+    ##
+    # :call-seq:
+    #   save(*args)
+    #
     # Saves the model.
     #
     # If the model is new, a record gets created in the database, otherwise
@@ -107,7 +246,7 @@ module ActiveRecord
     #
     # By default, save always runs validations. If any of them fail the action
     # is cancelled and #save returns +false+, and the record won't be saved. However, if you supply
-    # validate: false, validations are bypassed altogether. See
+    # <tt>validate: false</tt>, validations are bypassed altogether. See
     # ActiveRecord::Validations for more information.
     #
     # By default, #save also sets the +updated_at+/+updated_on+ attributes to
@@ -121,12 +260,16 @@ module ActiveRecord
     #
     # Attributes marked as readonly are silently ignored if the record is
     # being updated.
-    def save(*args)
-      create_or_update(*args)
+    def save(*args, &block)
+      create_or_update(*args, &block)
     rescue ActiveRecord::RecordInvalid
       false
     end
 
+    ##
+    # :call-seq:
+    #   save!(*args)
+    #
     # Saves the model.
     #
     # If the model is new, a record gets created in the database, otherwise
@@ -134,7 +277,7 @@ module ActiveRecord
     #
     # By default, #save! always runs validations. If any of them fail
     # ActiveRecord::RecordInvalid gets raised, and the record won't be saved. However, if you supply
-    # validate: false, validations are bypassed altogether. See
+    # <tt>validate: false</tt>, validations are bypassed altogether. See
     # ActiveRecord::Validations for more information.
     #
     # By default, #save! also sets the +updated_at+/+updated_on+ attributes to
@@ -148,8 +291,10 @@ module ActiveRecord
     #
     # Attributes marked as readonly are silently ignored if the record is
     # being updated.
-    def save!(*args)
-      create_or_update(*args) || raise(RecordNotSaved.new("Failed to save the record", self))
+    #
+    # Unless an error is raised, returns true.
+    def save!(*args, &block)
+      create_or_update(*args, &block) || raise(RecordNotSaved.new("Failed to save the record", self))
     end
 
     # Deletes the record in the database and freezes this instance to
@@ -165,7 +310,7 @@ module ActiveRecord
     # callbacks or any <tt>:dependent</tt> association
     # options, use <tt>#destroy</tt>.
     def delete
-      self.class.delete(id) if persisted?
+      _relation_for_itself.delete_all if persisted?
       @destroyed = true
       freeze
     end
@@ -178,10 +323,14 @@ module ActiveRecord
     # and #destroy returns +false+.
     # See ActiveRecord::Callbacks for further details.
     def destroy
-      raise ReadOnlyRecord, "#{self.class} is marked as readonly" if readonly?
+      _raise_readonly_record_error if readonly?
       destroy_associations
       self.class.connection.add_transaction_record(self)
-      destroy_row if persisted?
+      @_trigger_destroy_callback = if persisted?
+        destroy_row > 0
+      else
+        true
+      end
       @destroyed = true
       freeze
     end
@@ -212,7 +361,7 @@ module ActiveRecord
     def becomes(klass)
       became = klass.new
       became.instance_variable_set("@attributes", @attributes)
-      became.instance_variable_set("@mutation_tracker", @mutation_tracker) if defined?(@mutation_tracker)
+      became.instance_variable_set("@mutations_from_database", @mutations_from_database) if defined?(@mutations_from_database)
       became.instance_variable_set("@changed_attributes", attributes_changed_by_setter)
       became.instance_variable_set("@new_record", new_record?)
       became.instance_variable_set("@destroyed", destroyed?)
@@ -252,7 +401,8 @@ module ActiveRecord
       name = name.to_s
       verify_readonly_attribute(name)
       public_send("#{name}=", value)
-      save(validate: false) if changed?
+
+      save(validate: false)
     end
 
     # Updates the attributes of the model from the passed-in hash and saves the
@@ -311,10 +461,10 @@ module ActiveRecord
         verify_readonly_attribute(key.to_s)
       end
 
-      updated_count = self.class.unscoped.where(self.class.primary_key => id).update_all(attributes)
+      updated_count = _relation_for_itself.update_all(attributes)
 
       attributes.each do |k, v|
-        raw_write_attribute(k, v)
+        write_attribute_without_type_cast(k, v)
       end
 
       updated_count == 1
@@ -329,14 +479,16 @@ module ActiveRecord
       self
     end
 
-    # Wrapper around #increment that saves the record. This method differs from
-    # its non-bang version in that it passes through the attribute setter.
-    # Saving is not subjected to validation checks. Returns +true+ if the
-    # record could be saved.
-    def increment!(attribute, by = 1)
+    # Wrapper around #increment that writes the update to the database.
+    # Only +attribute+ is updated; the record itself is not saved.
+    # This means that any other modified attributes will still be dirty.
+    # Validations and callbacks are skipped. Supports the +touch+ option from
+    # +update_counters+, see that for more.
+    # Returns +self+.
+    def increment!(attribute, by = 1, touch: nil)
       increment(attribute, by)
-      change = public_send(attribute) - (attribute_was(attribute.to_s) || 0)
-      self.class.update_counters(id, attribute => change)
+      change = public_send(attribute) - (attribute_in_database(attribute.to_s) || 0)
+      self.class.update_counters(id, attribute => change, touch: touch)
       clear_attribute_change(attribute) # eww
       self
     end
@@ -348,12 +500,14 @@ module ActiveRecord
       increment(attribute, -by)
     end
 
-    # Wrapper around #decrement that saves the record. This method differs from
-    # its non-bang version in the sense that it passes through the attribute setter.
-    # Saving is not subjected to validation checks. Returns +true+ if the
-    # record could be saved.
-    def decrement!(attribute, by = 1)
-      increment!(attribute, -by)
+    # Wrapper around #decrement that writes the update to the database.
+    # Only +attribute+ is updated; the record itself is not saved.
+    # This means that any other modified attributes will still be dirty.
+    # Validations and callbacks are skipped. Supports the +touch+ option from
+    # +update_counters+, see that for more.
+    # Returns +self+.
+    def decrement!(attribute, by = 1, touch: nil)
+      increment!(attribute, -by, touch: touch)
     end
 
     # Assigns to +attribute+ the boolean opposite of <tt>attribute?</tt>. So
@@ -383,8 +537,8 @@ module ActiveRecord
 
     # Reloads the record from the database.
     #
-    # This method finds record by its primary key (which could be assigned manually) and
-    # modifies the receiver in-place:
+    # This method finds the record by its primary key (which could be assigned
+    # manually) and modifies the receiver in-place:
     #
     #   account = Account.new
     #   # => #<Account id: nil, email: nil>
@@ -439,7 +593,7 @@ module ActiveRecord
           self.class.unscoped { self.class.find(id) }
         end
 
-      @attributes = fresh_object.instance_variable_get('@attributes')
+      @attributes = fresh_object.instance_variable_get("@attributes")
       @new_record = false
       self
     end
@@ -479,7 +633,12 @@ module ActiveRecord
     #   ball.touch(:updated_at)   # => raises ActiveRecordError
     #
     def touch(*names, time: nil)
-      raise ActiveRecordError, "cannot touch on a new record object" unless persisted?
+      unless persisted?
+        raise ActiveRecordError, <<-MSG.squish
+          cannot touch on a new or destroyed record object. Consider using
+          persisted?, new_record?, or destroyed? before touching
+        MSG
+      end
 
       time ||= current_time_from_proper_timezone
       attributes = timestamp_attributes_for_update_in_model
@@ -493,22 +652,22 @@ module ActiveRecord
           changes[column] = write_attribute(column, time)
         end
 
-        clear_attribute_changes(changes.keys)
-        primary_key = self.class.primary_key
-        scope = self.class.unscoped.where(primary_key => _read_attribute(primary_key))
+        scope = _relation_for_itself
 
         if locking_enabled?
           locking_column = self.class.locking_column
-          scope = scope.where(locking_column => _read_attribute(locking_column))
+          scope = scope.where(locking_column => read_attribute_before_type_cast(locking_column))
           changes[locking_column] = increment_lock
         end
 
+        clear_attribute_changes(changes.keys)
         result = scope.update_all(changes) == 1
 
         if !result && locking_enabled?
           raise ActiveRecord::StaleObjectError.new(self, "touch")
         end
 
+        @_trigger_update_callback = result
         result
       else
         true
@@ -526,12 +685,16 @@ module ActiveRecord
     end
 
     def relation_for_destroy
+      _relation_for_itself
+    end
+
+    def _relation_for_itself
       self.class.unscoped.where(self.class.primary_key => id)
     end
 
-    def create_or_update(*args)
-      raise ReadOnlyRecord, "#{self.class} is marked as readonly" if readonly?
-      result = new_record? ? _create_record : _update_record(*args)
+    def create_or_update(*args, &block)
+      _raise_readonly_record_error if readonly?
+      result = new_record? ? _create_record(&block) : _update_record(*args, &block)
       result != false
     end
 
@@ -540,10 +703,16 @@ module ActiveRecord
     def _update_record(attribute_names = self.attribute_names)
       attributes_values = arel_attributes_with_values_for_update(attribute_names)
       if attributes_values.empty?
-        0
+        rows_affected = 0
+        @_trigger_update_callback = true
       else
-        self.class.unscoped._update_record attributes_values, id, id_was
+        rows_affected = self.class._update_record(attributes_values, id, id_in_database)
+        @_trigger_update_callback = rows_affected > 0
       end
+
+      yield(self) if block_given?
+
+      rows_affected
     end
 
     # Creates a record with values matching those of the instance attributes
@@ -551,10 +720,13 @@ module ActiveRecord
     def _create_record(attribute_names = self.attribute_names)
       attributes_values = arel_attributes_with_values_for_create(attribute_names)
 
-      new_id = self.class.unscoped.insert attributes_values
+      new_id = self.class._insert_record(attributes_values)
       self.id ||= new_id if self.class.primary_key
 
       @new_record = false
+
+      yield(self) if block_given?
+
       id
     end
 
@@ -572,5 +744,9 @@ module ActiveRecord
     def belongs_to_touch_method
       :touch
     end
+
+    def _raise_readonly_record_error
+      raise ReadOnlyRecord, "#{self.class} is marked as readonly"
+    end
   end
 end
diff --git a/activerecord/lib/active_record/query_cache.rb b/activerecord/lib/active_record/query_cache.rb
index 07d863d15e..8e23128333 100644
--- a/activerecord/lib/active_record/query_cache.rb
+++ b/activerecord/lib/active_record/query_cache.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActiveRecord
   # = Active Record Query Cache
   class QueryCache
@@ -5,49 +7,46 @@ module ActiveRecord
       # Enable the query cache within the block if Active Record is configured.
       # If it's not, it will execute the given block.
       def cache(&block)
-        if connected?
-          connection.cache(&block)
-        else
+        if configurations.empty?
           yield
+        else
+          connection.cache(&block)
         end
       end
 
       # Disable the query cache within the block if Active Record is configured.
       # If it's not, it will execute the given block.
       def uncached(&block)
-        if connected?
-          connection.uncached(&block)
-        else
+        if configurations.empty?
           yield
+        else
+          connection.uncached(&block)
         end
       end
     end
 
     def self.run
-      connection    = ActiveRecord::Base.connection
-      enabled       = connection.query_cache_enabled
-      connection_id = ActiveRecord::Base.connection_id
-      connection.enable_query_cache!
+      ActiveRecord::Base.connection_handler.connection_pool_list.map do |pool|
+        caching_was_enabled = pool.query_cache_enabled
+
+        pool.enable_query_cache!
 
-      [enabled, connection_id]
+        [pool, caching_was_enabled]
+      end
     end
 
-    def self.complete(state)
-      enabled, connection_id = state
+    def self.complete(caching_pools)
+      caching_pools.each do |pool, caching_was_enabled|
+        pool.disable_query_cache! unless caching_was_enabled
+      end
 
-      ActiveRecord::Base.connection_id = connection_id
-      ActiveRecord::Base.connection.clear_query_cache
-      ActiveRecord::Base.connection.disable_query_cache! unless enabled
+      ActiveRecord::Base.connection_handler.connection_pool_list.each do |pool|
+        pool.release_connection if pool.active_connection? && !pool.connection.transaction_open?
+      end
     end
 
     def self.install_executor_hooks(executor = ActiveSupport::Executor)
       executor.register_hook(self)
-
-      executor.to_complete do
-        unless ActiveRecord::Base.connection.transaction_open?
-          ActiveRecord::Base.clear_active_connections!
-        end
-      end
     end
   end
 end
diff --git a/activerecord/lib/active_record/querying.rb b/activerecord/lib/active_record/querying.rb
index 53ddd95bb0..3996d5661f 100644
--- a/activerecord/lib/active_record/querying.rb
+++ b/activerecord/lib/active_record/querying.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActiveRecord
   module Querying
     delegate :find, :take, :take!, :first, :first!, :last, :last!, :exists?, :any?, :many?, :none?, :one?, to: :all
@@ -5,11 +7,11 @@ module ActiveRecord
     delegate :first_or_create, :first_or_create!, :first_or_initialize, to: :all
     delegate :find_or_create_by, :find_or_create_by!, :find_or_initialize_by, to: :all
     delegate :find_by, :find_by!, to: :all
-    delegate :destroy, :destroy_all, :delete, :delete_all, :update, :update_all, to: :all
+    delegate :destroy_all, :delete_all, :update_all, to: :all
     delegate :find_each, :find_in_batches, :in_batches, to: :all
     delegate :select, :group, :order, :except, :reorder, :limit, :offset, :joins, :left_joins, :left_outer_joins, :or,
-             :where, :rewhere, :preload, :eager_load, :includes, :from, :lock, :readonly,
-             :having, :create_with, :uniq, :distinct, :references, :none, :unscope, to: :all
+             :where, :rewhere, :preload, :eager_load, :includes, :from, :lock, :readonly, :extending,
+             :having, :create_with, :distinct, :references, :none, :unscope, :merge, to: :all
     delegate :count, :average, :minimum, :maximum, :sum, :calculate, to: :all
     delegate :pluck, :ids, to: :all
 
@@ -35,7 +37,7 @@ module ActiveRecord
     #
     #   Post.find_by_sql ["SELECT title FROM posts WHERE author = ? AND created > ?", author_id, start_date]
     #   Post.find_by_sql ["SELECT body FROM comments WHERE author = :user_id OR approved_by = :user_id", { :user_id => user_id }]
-    def find_by_sql(sql, binds = [], preparable: nil)
+    def find_by_sql(sql, binds = [], preparable: nil, &block)
       result_set = connection.select_all(sanitize_sql(sql), "#{name} Load", binds, preparable: preparable)
       column_types = result_set.column_types.dup
       columns_hash.each_key { |k| column_types.delete k }
@@ -46,8 +48,8 @@ module ActiveRecord
         class_name: name
       }
 
-      message_bus.instrument('instantiation.active_record', payload) do
-        result_set.map { |record| instantiate(record, column_types) }
+      message_bus.instrument("instantiation.active_record", payload) do
+        result_set.map { |record| instantiate(record, column_types, &block) }
       end
     end
 
@@ -62,8 +64,7 @@ module ActiveRecord
     #
     # * +sql+ - An SQL statement which should return a count query from the database, see the example above.
     def count_by_sql(sql)
-      sql = sanitize_conditions(sql)
-      connection.select_value(sql, "#{name} Count").to_i
+      connection.select_value(sanitize_sql(sql), "#{name} Count").to_i
     end
   end
 end
diff --git a/activerecord/lib/active_record/railtie.rb b/activerecord/lib/active_record/railtie.rb
index 98ea425d16..4538ed6a5f 100644
--- a/activerecord/lib/active_record/railtie.rb
+++ b/activerecord/lib/active_record/railtie.rb
@@ -1,9 +1,11 @@
+# frozen_string_literal: true
+
 require "active_record"
 require "rails"
 require "active_model/railtie"
 
 # For now, action_controller must always be present with
-# rails, so let's make sure that it gets required before
+# Rails, so let's make sure that it gets required before
 # here. This is needed for correctly setting up the middleware.
 # In the future, this might become an optional require.
 require "action_controller/railtie"
@@ -13,20 +15,22 @@ module ActiveRecord
   class Railtie < Rails::Railtie # :nodoc:
     config.active_record = ActiveSupport::OrderedOptions.new
 
-    config.app_generators.orm :active_record, :migration => true,
-                                              :timestamps => true
+    config.app_generators.orm :active_record, migration: true,
+                                              timestamps: true
 
     config.action_dispatch.rescue_responses.merge!(
-      'ActiveRecord::RecordNotFound'   => :not_found,
-      'ActiveRecord::StaleObjectError' => :conflict,
-      'ActiveRecord::RecordInvalid'    => :unprocessable_entity,
-      'ActiveRecord::RecordNotSaved'   => :unprocessable_entity
+      "ActiveRecord::RecordNotFound"   => :not_found,
+      "ActiveRecord::StaleObjectError" => :conflict,
+      "ActiveRecord::RecordInvalid"    => :unprocessable_entity,
+      "ActiveRecord::RecordNotSaved"   => :unprocessable_entity
     )
 
-
     config.active_record.use_schema_cache_dump = true
     config.active_record.maintain_test_schema = true
 
+    config.active_record.sqlite3 = ActiveSupport::OrderedOptions.new
+    config.active_record.sqlite3.represent_boolean_as_integer = nil
+
     config.eager_load_namespaces << ActiveRecord
 
     rake_tasks do
@@ -35,8 +39,8 @@ module ActiveRecord
           ActiveRecord::Tasks::DatabaseTasks.database_configuration = Rails.application.config.database_configuration
 
           if defined?(ENGINE_ROOT) && engine = Rails::Engine.find(ENGINE_ROOT)
-            if engine.paths['db/migrate'].existent
-              ActiveRecord::Tasks::DatabaseTasks.migrations_paths += engine.paths['db/migrate'].to_a
+            if engine.paths["db/migrate"].existent
+              ActiveRecord::Tasks::DatabaseTasks.migrations_paths += engine.paths["db/migrate"].to_a
             end
           end
         end
@@ -83,15 +87,18 @@ module ActiveRecord
       if config.active_record.delete(:use_schema_cache_dump)
         config.after_initialize do |app|
           ActiveSupport.on_load(:active_record) do
-            filename = File.join(app.config.paths["db"].first, "schema_cache.dump")
+            filename = File.join(app.config.paths["db"].first, "schema_cache.yml")
 
             if File.file?(filename)
-              cache = Marshal.load File.binread filename
-              if cache.version == ActiveRecord::Migrator.current_version
-                self.connection.schema_cache = cache
-                self.connection_pool.schema_cache = cache.dup
+              current_version = ActiveRecord::Migrator.current_version
+              next if current_version.nil?
+
+              cache = YAML.load(File.read(filename))
+              if cache.version == current_version
+                connection.schema_cache = cache
+                connection_pool.schema_cache = cache.dup
               else
-                warn "Ignoring db/schema_cache.dump because it has expired. The current schema version is #{ActiveRecord::Migrator.current_version}, but the one in the cache is #{cache.version}."
+                warn "Ignoring db/schema_cache.yml because it has expired. The current schema version is #{current_version}, but the one in the cache is #{cache.version}."
               end
             end
           end
@@ -102,14 +109,16 @@ module ActiveRecord
     initializer "active_record.warn_on_records_fetched_greater_than" do
       if config.active_record.warn_on_records_fetched_greater_than
         ActiveSupport.on_load(:active_record) do
-          require 'active_record/relation/record_fetch_warning'
+          require "active_record/relation/record_fetch_warning"
         end
       end
     end
 
     initializer "active_record.set_configs" do |app|
       ActiveSupport.on_load(:active_record) do
-        app.config.active_record.each do |k,v|
+        configs = app.config.active_record.dup
+        configs.delete(:sqlite3)
+        configs.each do |k, v|
           send "#{k}=", v
         end
       end
@@ -167,5 +176,51 @@ end_warning
       path = app.paths["db"].first
       config.watchable_files.concat ["#{path}/schema.rb", "#{path}/structure.sql"]
     end
+
+    initializer "active_record.clear_active_connections" do
+      config.after_initialize do
+        ActiveSupport.on_load(:active_record) do
+          # Ideally the application doesn't connect to the database during boot,
+          # but sometimes it does. In case it did, we want to empty out the
+          # connection pools so that a non-database-using process (e.g. a master
+          # process in a forking server model) doesn't retain a needless
+          # connection. If it was needed, the incremental cost of reestablishing
+          # this connection is trivial: the rest of the pool would need to be
+          # populated anyway.
+
+          clear_active_connections!
+          flush_idle_connections!
+        end
+      end
+    end
+
+    initializer "active_record.check_represent_sqlite3_boolean_as_integer" do
+      config.after_initialize do
+        ActiveSupport.on_load(:active_record_sqlite3adapter) do
+          represent_boolean_as_integer = Rails.application.config.active_record.sqlite3.delete(:represent_boolean_as_integer)
+          unless represent_boolean_as_integer.nil?
+            ActiveRecord::ConnectionAdapters::SQLite3Adapter.represent_boolean_as_integer = represent_boolean_as_integer
+          end
+
+          unless ActiveRecord::ConnectionAdapters::SQLite3Adapter.represent_boolean_as_integer
+            ActiveSupport::Deprecation.warn <<-MSG
+Leaving `ActiveRecord::ConnectionAdapters::SQLite3Adapter.represent_boolean_as_integer`
+set to false is deprecated. SQLite databases have used 't' and 'f' to serialize
+boolean values and must have old data converted to 1 and 0 (its native boolean
+serialization) before setting this flag to true. Conversion can be accomplished
+by setting up a rake task which runs
+
+  ExampleModel.where("boolean_column = 't'").update_all(boolean_column: 1)
+  ExampleModel.where("boolean_column = 'f'").update_all(boolean_column: 0)
+
+for all models and all boolean columns, after which the flag must be set to
+true by adding the following to your application.rb file:
+
+  Rails.application.config.active_record.sqlite3.represent_boolean_as_integer = true
+MSG
+          end
+        end
+      end
+    end
   end
 end
diff --git a/activerecord/lib/active_record/railties/console_sandbox.rb b/activerecord/lib/active_record/railties/console_sandbox.rb
index 604a220303..8917638a5d 100644
--- a/activerecord/lib/active_record/railties/console_sandbox.rb
+++ b/activerecord/lib/active_record/railties/console_sandbox.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 ActiveRecord::Base.connection.begin_transaction(joinable: false)
 
 at_exit do
diff --git a/activerecord/lib/active_record/railties/controller_runtime.rb b/activerecord/lib/active_record/railties/controller_runtime.rb
index 8727e46cb3..2ae733f657 100644
--- a/activerecord/lib/active_record/railties/controller_runtime.rb
+++ b/activerecord/lib/active_record/railties/controller_runtime.rb
@@ -1,15 +1,21 @@
-require 'active_support/core_ext/module/attr_internal'
-require 'active_record/log_subscriber'
+# frozen_string_literal: true
+
+require "active_support/core_ext/module/attr_internal"
+require "active_record/log_subscriber"
 
 module ActiveRecord
   module Railties # :nodoc:
     module ControllerRuntime #:nodoc:
       extend ActiveSupport::Concern
 
+    # TODO Change this to private once we've dropped Ruby 2.2 support.
+    # Workaround for Ruby 2.2 "private attribute?" warning.
     protected
 
       attr_internal :db_runtime
 
+    private
+
       def process_action(action, *args)
         # We also need to reset the runtime before each action
         # because of queries in middleware or in cases we are streaming
@@ -19,7 +25,7 @@ module ActiveRecord
       end
 
       def cleanup_view_runtime
-        if logger.info? && ActiveRecord::Base.connected?
+        if logger && logger.info? && ActiveRecord::Base.connected?
           db_rt_before_render = ActiveRecord::LogSubscriber.reset_runtime
           self.db_runtime = (db_runtime || 0) + db_rt_before_render
           runtime = super
diff --git a/activerecord/lib/active_record/railties/databases.rake b/activerecord/lib/active_record/railties/databases.rake
index fc1b62ee96..fce3e1c5cf 100644
--- a/activerecord/lib/active_record/railties/databases.rake
+++ b/activerecord/lib/active_record/railties/databases.rake
@@ -1,40 +1,42 @@
-require 'active_record'
+# frozen_string_literal: true
+
+require "active_record"
 
 db_namespace = namespace :db do
   desc "Set the environment value for the database"
-  task "environment:set" => [:environment, :load_config] do
+  task "environment:set" => :load_config do
     ActiveRecord::InternalMetadata.create_table
     ActiveRecord::InternalMetadata[:environment] = ActiveRecord::Migrator.current_environment
   end
 
-  task :check_protected_environments => [:environment, :load_config] do
+  task check_protected_environments: :load_config do
     ActiveRecord::Tasks::DatabaseTasks.check_protected_environments!
   end
 
-  task :load_config do
+  task load_config: :environment do
     ActiveRecord::Base.configurations       = ActiveRecord::Tasks::DatabaseTasks.database_configuration || {}
     ActiveRecord::Migrator.migrations_paths = ActiveRecord::Tasks::DatabaseTasks.migrations_paths
   end
 
   namespace :create do
-    task :all => :load_config do
+    task all: :load_config do
       ActiveRecord::Tasks::DatabaseTasks.create_all
     end
   end
 
-  desc 'Creates the database from DATABASE_URL or config/database.yml for the current RAILS_ENV (use db:create:all to create all databases in the config). Without RAILS_ENV or when RAILS_ENV is development, it defaults to creating the development and test databases.'
-  task :create => [:load_config] do
+  desc "Creates the database from DATABASE_URL or config/database.yml for the current RAILS_ENV (use db:create:all to create all databases in the config). Without RAILS_ENV or when RAILS_ENV is development, it defaults to creating the development and test databases."
+  task create: [:load_config] do
     ActiveRecord::Tasks::DatabaseTasks.create_current
   end
 
   namespace :drop do
-    task :all => [:load_config, :check_protected_environments] do
+    task all: [:load_config, :check_protected_environments] do
       ActiveRecord::Tasks::DatabaseTasks.drop_all
     end
   end
 
-  desc 'Drops the database from DATABASE_URL or config/database.yml for the current RAILS_ENV (use db:drop:all to drop all databases in the config). Without RAILS_ENV or when RAILS_ENV is development, it defaults to dropping the development and test databases.'
-  task :drop => [:load_config, :check_protected_environments] do
+  desc "Drops the database from DATABASE_URL or config/database.yml for the current RAILS_ENV (use db:drop:all to drop all databases in the config). Without RAILS_ENV or when RAILS_ENV is development, it defaults to dropping the development and test databases."
+  task drop: [:load_config, :check_protected_environments] do
     db_namespace["drop:_unsafe"].invoke
   end
 
@@ -43,20 +45,20 @@ db_namespace = namespace :db do
   end
 
   namespace :purge do
-    task :all => [:load_config, :check_protected_environments] do
+    task all: [:load_config, :check_protected_environments] do
       ActiveRecord::Tasks::DatabaseTasks.purge_all
     end
   end
 
   # desc "Empty the database from DATABASE_URL or config/database.yml for the current RAILS_ENV (use db:purge:all to purge all databases in the config). Without RAILS_ENV it defaults to purging the development and test databases."
-  task :purge => [:load_config, :check_protected_environments] do
+  task purge: [:load_config, :check_protected_environments] do
     ActiveRecord::Tasks::DatabaseTasks.purge_current
   end
 
   desc "Migrate the database (options: VERSION=x, VERBOSE=false, SCOPE=blog)."
-  task :migrate => [:environment, :load_config] do
+  task migrate: :load_config do
     ActiveRecord::Tasks::DatabaseTasks.migrate
-    db_namespace['_dump'].invoke
+    db_namespace["_dump"].invoke
   end
 
   # IMPORTANT: This task won't dump the schema if ActiveRecord::Base.dump_schema_after_migration is set to false
@@ -71,160 +73,159 @@ db_namespace = namespace :db do
     end
     # Allow this task to be called as many times as required. An example is the
     # migrate:redo task, which calls other two internally that depend on this one.
-    db_namespace['_dump'].reenable
+    db_namespace["_dump"].reenable
   end
 
   namespace :migrate do
     # desc  'Rollbacks the database one migration and re migrate up (options: STEP=x, VERSION=x).'
-    task :redo => [:environment, :load_config] do
-      if ENV['VERSION']
-        db_namespace['migrate:down'].invoke
-        db_namespace['migrate:up'].invoke
+    task redo: :load_config do
+      raise "Empty VERSION provided" if ENV["VERSION"] && ENV["VERSION"].empty?
+
+      if ENV["VERSION"]
+        db_namespace["migrate:down"].invoke
+        db_namespace["migrate:up"].invoke
       else
-        db_namespace['rollback'].invoke
-        db_namespace['migrate'].invoke
+        db_namespace["rollback"].invoke
+        db_namespace["migrate"].invoke
       end
     end
 
     # desc 'Resets your database using your migrations for the current environment'
-    task :reset => ['db:drop', 'db:create', 'db:migrate']
+    task reset: ["db:drop", "db:create", "db:migrate"]
 
     # desc 'Runs the "up" for a given migration VERSION.'
-    task :up => [:environment, :load_config] do
-      version = ENV['VERSION'] ? ENV['VERSION'].to_i : nil
-      raise 'VERSION is required' unless version
-      ActiveRecord::Migrator.run(:up, ActiveRecord::Tasks::DatabaseTasks.migrations_paths, version)
-      db_namespace['_dump'].invoke
+    task up: :load_config do
+      raise "VERSION is required" if !ENV["VERSION"] || ENV["VERSION"].empty?
+
+      ActiveRecord::Tasks::DatabaseTasks.check_target_version
+
+      ActiveRecord::Migrator.run(
+        :up,
+        ActiveRecord::Tasks::DatabaseTasks.migrations_paths,
+        ActiveRecord::Tasks::DatabaseTasks.target_version
+      )
+      db_namespace["_dump"].invoke
     end
 
     # desc 'Runs the "down" for a given migration VERSION.'
-    task :down => [:environment, :load_config] do
-      version = ENV['VERSION'] ? ENV['VERSION'].to_i : nil
-      raise 'VERSION is required - To go down one migration, run db:rollback' unless version
-      ActiveRecord::Migrator.run(:down, ActiveRecord::Tasks::DatabaseTasks.migrations_paths, version)
-      db_namespace['_dump'].invoke
+    task down: :load_config do
+      raise "VERSION is required - To go down one migration, use db:rollback" if !ENV["VERSION"] || ENV["VERSION"].empty?
+
+      ActiveRecord::Tasks::DatabaseTasks.check_target_version
+
+      ActiveRecord::Migrator.run(
+        :down,
+        ActiveRecord::Tasks::DatabaseTasks.migrations_paths,
+        ActiveRecord::Tasks::DatabaseTasks.target_version
+      )
+      db_namespace["_dump"].invoke
     end
 
-    desc 'Display status of migrations'
-    task :status => [:environment, :load_config] do
+    desc "Display status of migrations"
+    task status: :load_config do
       unless ActiveRecord::SchemaMigration.table_exists?
-        abort 'Schema migrations table does not exist yet.'
+        abort "Schema migrations table does not exist yet."
       end
-      db_list = ActiveRecord::SchemaMigration.normalized_versions
-
-      file_list =
-          ActiveRecord::Tasks::DatabaseTasks.migrations_paths.flat_map do |path|
-            Dir.foreach(path).map do |file|
-              next unless ActiveRecord::Migrator.match_to_migration_filename?(file)
-
-              version, name, scope = ActiveRecord::Migrator.parse_migration_filename(file)
-              version = ActiveRecord::SchemaMigration.normalize_migration_number(version)
-              status = db_list.delete(version) ? 'up' : 'down'
-              [status, version, (name + scope).humanize]
-            end.compact
-          end
 
-      db_list.map! do |version|
-        ['up', version, '********** NO FILE **********']
-      end
       # output
       puts "\ndatabase: #{ActiveRecord::Base.connection_config[:database]}\n\n"
       puts "#{'Status'.center(8)}  #{'Migration ID'.ljust(14)}  Migration Name"
       puts "-" * 50
-      (db_list + file_list).sort_by { |_, version, _| version }.each do |status, version, name|
+      paths = ActiveRecord::Tasks::DatabaseTasks.migrations_paths
+      ActiveRecord::Migrator.migrations_status(paths).each do |status, version, name|
         puts "#{status.center(8)}  #{version.ljust(14)}  #{name}"
       end
       puts
     end
   end
 
-  desc 'Rolls the schema back to the previous version (specify steps w/ STEP=n).'
-  task :rollback => [:environment, :load_config] do
-    step = ENV['STEP'] ? ENV['STEP'].to_i : 1
+  desc "Rolls the schema back to the previous version (specify steps w/ STEP=n)."
+  task rollback: :load_config do
+    step = ENV["STEP"] ? ENV["STEP"].to_i : 1
     ActiveRecord::Migrator.rollback(ActiveRecord::Tasks::DatabaseTasks.migrations_paths, step)
-    db_namespace['_dump'].invoke
+    db_namespace["_dump"].invoke
   end
 
   # desc 'Pushes the schema to the next version (specify steps w/ STEP=n).'
-  task :forward => [:environment, :load_config] do
-    step = ENV['STEP'] ? ENV['STEP'].to_i : 1
+  task forward: :load_config do
+    step = ENV["STEP"] ? ENV["STEP"].to_i : 1
     ActiveRecord::Migrator.forward(ActiveRecord::Tasks::DatabaseTasks.migrations_paths, step)
-    db_namespace['_dump'].invoke
+    db_namespace["_dump"].invoke
   end
 
   # desc 'Drops and recreates the database from db/schema.rb for the current environment and loads the seeds.'
-  task :reset => [ 'db:drop', 'db:setup' ]
+  task reset: [ "db:drop", "db:setup" ]
 
   # desc "Retrieves the charset for the current environment's database"
-  task :charset => [:environment, :load_config] do
+  task charset: :load_config do
     puts ActiveRecord::Tasks::DatabaseTasks.charset_current
   end
 
   # desc "Retrieves the collation for the current environment's database"
-  task :collation => [:environment, :load_config] do
+  task collation: :load_config do
     begin
       puts ActiveRecord::Tasks::DatabaseTasks.collation_current
     rescue NoMethodError
-      $stderr.puts 'Sorry, your database adapter is not supported yet. Feel free to submit a patch.'
+      $stderr.puts "Sorry, your database adapter is not supported yet. Feel free to submit a patch."
     end
   end
 
-  desc 'Retrieves the current schema version number'
-  task :version => [:environment, :load_config] do
+  desc "Retrieves the current schema version number"
+  task version: :load_config do
     puts "Current version: #{ActiveRecord::Migrator.current_version}"
   end
 
   # desc "Raises an error if there are pending migrations"
-  task :abort_if_pending_migrations => [:environment, :load_config] do
+  task abort_if_pending_migrations: :load_config do
     pending_migrations = ActiveRecord::Migrator.open(ActiveRecord::Tasks::DatabaseTasks.migrations_paths).pending_migrations
 
     if pending_migrations.any?
       puts "You have #{pending_migrations.size} pending #{pending_migrations.size > 1 ? 'migrations:' : 'migration:'}"
       pending_migrations.each do |pending_migration|
-        puts '  %4d %s' % [pending_migration.version, pending_migration.name]
+        puts "  %4d %s" % [pending_migration.version, pending_migration.name]
       end
       abort %{Run `rails db:migrate` to update your database then try again.}
     end
   end
 
-  desc 'Creates the database, loads the schema, and initializes with the seed data (use db:reset to also drop the database first)'
-  task :setup => ['db:schema:load_if_ruby', 'db:structure:load_if_sql', :seed]
+  desc "Creates the database, loads the schema, and initializes with the seed data (use db:reset to also drop the database first)"
+  task setup: ["db:schema:load_if_ruby", "db:structure:load_if_sql", :seed]
 
-  desc 'Loads the seed data from db/seeds.rb'
+  desc "Loads the seed data from db/seeds.rb"
   task :seed do
-    db_namespace['abort_if_pending_migrations'].invoke
+    db_namespace["abort_if_pending_migrations"].invoke
     ActiveRecord::Tasks::DatabaseTasks.load_seed
   end
 
   namespace :fixtures do
     desc "Loads fixtures into the current environment's database. Load specific fixtures using FIXTURES=x,y. Load from subdirectory in test/fixtures using FIXTURES_DIR=z. Specify an alternative path (eg. spec/fixtures) using FIXTURES_PATH=spec/fixtures."
-    task :load => [:environment, :load_config] do
-      require 'active_record/fixtures'
+    task load: :load_config do
+      require "active_record/fixtures"
 
       base_dir = ActiveRecord::Tasks::DatabaseTasks.fixtures_path
 
-      fixtures_dir = if ENV['FIXTURES_DIR']
-                       File.join base_dir, ENV['FIXTURES_DIR']
-                     else
-                       base_dir
-                     end
+      fixtures_dir = if ENV["FIXTURES_DIR"]
+        File.join base_dir, ENV["FIXTURES_DIR"]
+      else
+        base_dir
+      end
 
-      fixture_files = if ENV['FIXTURES']
-                        ENV['FIXTURES'].split(',')
-                      else
-                        # The use of String#[] here is to support namespaced fixtures
-                        Dir["#{fixtures_dir}/**/*.yml"].map {|f| f[(fixtures_dir.size + 1)..-5] }
-                      end
+      fixture_files = if ENV["FIXTURES"]
+        ENV["FIXTURES"].split(",")
+      else
+        # The use of String#[] here is to support namespaced fixtures.
+        Dir["#{fixtures_dir}/**/*.yml"].map { |f| f[(fixtures_dir.size + 1)..-5] }
+      end
 
       ActiveRecord::FixtureSet.create_fixtures(fixtures_dir, fixture_files)
     end
 
     # desc "Search for a fixture given a LABEL or ID. Specify an alternative path (eg. spec/fixtures) using FIXTURES_PATH=spec/fixtures."
-    task :identify => [:environment, :load_config] do
-      require 'active_record/fixtures'
+    task identify: :load_config do
+      require "active_record/fixtures"
 
-      label, id = ENV['LABEL'], ENV['ID']
-      raise 'LABEL or ID required' if label.blank? && id.blank?
+      label, id = ENV["LABEL"], ENV["ID"]
+      raise "LABEL or ID required" if label.blank? && id.blank?
 
       puts %Q(The fixture ID for "#{label}" is #{ActiveRecord::FixtureSet.identify(label)}.) if label
 
@@ -245,39 +246,36 @@ db_namespace = namespace :db do
   end
 
   namespace :schema do
-    desc 'Creates a db/schema.rb file that is portable against any DB supported by Active Record'
-    task :dump => [:environment, :load_config] do
-      require 'active_record/schema_dumper'
-      filename = ENV['SCHEMA'] || File.join(ActiveRecord::Tasks::DatabaseTasks.db_dir, 'schema.rb')
+    desc "Creates a db/schema.rb file that is portable against any DB supported by Active Record"
+    task dump: :load_config do
+      require "active_record/schema_dumper"
+      filename = ENV["SCHEMA"] || File.join(ActiveRecord::Tasks::DatabaseTasks.db_dir, "schema.rb")
       File.open(filename, "w:utf-8") do |file|
         ActiveRecord::SchemaDumper.dump(ActiveRecord::Base.connection, file)
       end
-      db_namespace['schema:dump'].reenable
+      db_namespace["schema:dump"].reenable
     end
 
-    desc 'Loads a schema.rb file into the database'
-    task :load => [:environment, :load_config, :check_protected_environments] do
-      ActiveRecord::Tasks::DatabaseTasks.load_schema_current(:ruby, ENV['SCHEMA'])
+    desc "Loads a schema.rb file into the database"
+    task load: [:load_config, :check_protected_environments] do
+      ActiveRecord::Tasks::DatabaseTasks.load_schema_current(:ruby, ENV["SCHEMA"])
     end
 
-    task :load_if_ruby => ['db:create', :environment] do
+    task load_if_ruby: ["db:create", :environment] do
       db_namespace["schema:load"].invoke if ActiveRecord::Base.schema_format == :ruby
     end
 
     namespace :cache do
-      desc 'Creates a db/schema_cache.dump file.'
-      task :dump => [:environment, :load_config] do
-        con = ActiveRecord::Base.connection
-        filename = File.join(ActiveRecord::Tasks::DatabaseTasks.db_dir, "schema_cache.dump")
-
-        con.schema_cache.clear!
-        con.data_sources.each { |table| con.schema_cache.add(table) }
-        open(filename, 'wb') { |f| f.write(Marshal.dump(con.schema_cache)) }
+      desc "Creates a db/schema_cache.yml file."
+      task dump: :load_config do
+        conn = ActiveRecord::Base.connection
+        filename = File.join(ActiveRecord::Tasks::DatabaseTasks.db_dir, "schema_cache.yml")
+        ActiveRecord::Tasks::DatabaseTasks.dump_schema_cache(conn, filename)
       end
 
-      desc 'Clears a db/schema_cache.dump file.'
-      task :clear => [:environment, :load_config] do
-        filename = File.join(ActiveRecord::Tasks::DatabaseTasks.db_dir, "schema_cache.dump")
+      desc "Clears a db/schema_cache.yml file."
+      task clear: :load_config do
+        filename = File.join(ActiveRecord::Tasks::DatabaseTasks.db_dir, "schema_cache.yml")
         rm_f filename, verbose: false
       end
     end
@@ -285,57 +283,48 @@ db_namespace = namespace :db do
   end
 
   namespace :structure do
-    desc 'Dumps the database structure to db/structure.sql. Specify another file with SCHEMA=db/my_structure.sql'
-    task :dump => [:environment, :load_config] do
-      filename = ENV['SCHEMA'] || File.join(ActiveRecord::Tasks::DatabaseTasks.db_dir, "structure.sql")
+    desc "Dumps the database structure to db/structure.sql. Specify another file with SCHEMA=db/my_structure.sql"
+    task dump: :load_config do
+      filename = ENV["SCHEMA"] || File.join(ActiveRecord::Tasks::DatabaseTasks.db_dir, "structure.sql")
       current_config = ActiveRecord::Tasks::DatabaseTasks.current_config
       ActiveRecord::Tasks::DatabaseTasks.structure_dump(current_config, filename)
 
-      if ActiveRecord::Base.connection.supports_migrations? &&
-          ActiveRecord::SchemaMigration.table_exists?
+      if ActiveRecord::SchemaMigration.table_exists?
         File.open(filename, "a") do |f|
           f.puts ActiveRecord::Base.connection.dump_schema_information
           f.print "\n"
         end
       end
-      db_namespace['structure:dump'].reenable
+      db_namespace["structure:dump"].reenable
     end
 
     desc "Recreates the databases from the structure.sql file"
-    task :load => [:environment, :load_config, :check_protected_environments] do
-      ActiveRecord::Tasks::DatabaseTasks.load_schema_current(:sql, ENV['SCHEMA'])
+    task load: [:load_config, :check_protected_environments] do
+      ActiveRecord::Tasks::DatabaseTasks.load_schema_current(:sql, ENV["SCHEMA"])
     end
 
-    task :load_if_sql => ['db:create', :environment] do
+    task load_if_sql: ["db:create", :environment] do
       db_namespace["structure:load"].invoke if ActiveRecord::Base.schema_format == :sql
     end
   end
 
   namespace :test do
-
-    task :deprecated do
-      Rake.application.top_level_tasks.grep(/^db:test:/).each do |task|
-        $stderr.puts "WARNING: #{task} is deprecated. The Rails test helper now maintains " \
-                     "your test schema automatically, see the release notes for details."
-      end
-    end
-
     # desc "Recreate the test database from the current schema"
-    task :load => %w(db:test:purge) do
+    task load: %w(db:test:purge) do
       case ActiveRecord::Base.schema_format
-        when :ruby
-          db_namespace["test:load_schema"].invoke
-        when :sql
-          db_namespace["test:load_structure"].invoke
+      when :ruby
+        db_namespace["test:load_schema"].invoke
+      when :sql
+        db_namespace["test:load_structure"].invoke
       end
     end
 
     # desc "Recreate the test database from an existent schema.rb file"
-    task :load_schema => %w(db:test:purge) do
+    task load_schema: %w(db:test:purge) do
       begin
         should_reconnect = ActiveRecord::Base.connection_pool.active_connection?
         ActiveRecord::Schema.verbose = false
-        ActiveRecord::Tasks::DatabaseTasks.load_schema ActiveRecord::Base.configurations['test'], :ruby, ENV['SCHEMA']
+        ActiveRecord::Tasks::DatabaseTasks.load_schema ActiveRecord::Base.configurations["test"], :ruby, ENV["SCHEMA"], "test"
       ensure
         if should_reconnect
           ActiveRecord::Base.establish_connection(ActiveRecord::Base.configurations[ActiveRecord::Tasks::DatabaseTasks.env])
@@ -344,35 +333,19 @@ db_namespace = namespace :db do
     end
 
     # desc "Recreate the test database from an existent structure.sql file"
-    task :load_structure => %w(db:test:purge) do
-      ActiveRecord::Tasks::DatabaseTasks.load_schema ActiveRecord::Base.configurations['test'], :sql, ENV['SCHEMA']
+    task load_structure: %w(db:test:purge) do
+      ActiveRecord::Tasks::DatabaseTasks.load_schema ActiveRecord::Base.configurations["test"], :sql, ENV["SCHEMA"], "test"
     end
 
-    # desc "Recreate the test database from a fresh schema"
-    task :clone => %w(db:test:deprecated environment) do
-      case ActiveRecord::Base.schema_format
-        when :ruby
-          db_namespace["test:clone_schema"].invoke
-        when :sql
-          db_namespace["test:clone_structure"].invoke
-      end
-    end
-
-    # desc "Recreate the test database from a fresh schema.rb file"
-    task :clone_schema => %w(db:test:deprecated db:schema:dump db:test:load_schema)
-
-    # desc "Recreate the test database from a fresh structure.sql file"
-    task :clone_structure => %w(db:test:deprecated db:structure:dump db:test:load_structure)
-
     # desc "Empty the test database"
-    task :purge => %w(environment load_config check_protected_environments) do
-      ActiveRecord::Tasks::DatabaseTasks.purge ActiveRecord::Base.configurations['test']
+    task purge: %w(load_config check_protected_environments) do
+      ActiveRecord::Tasks::DatabaseTasks.purge ActiveRecord::Base.configurations["test"]
     end
 
     # desc 'Load the test schema'
-    task :prepare => %w(environment load_config) do
+    task prepare: :load_config do
       unless ActiveRecord::Base.configurations.blank?
-        db_namespace['test:load'].invoke
+        db_namespace["test:load"].invoke
       end
     end
   end
@@ -381,13 +354,13 @@ end
 namespace :railties do
   namespace :install do
     # desc "Copies missing migrations from Railties (e.g. engines). You can specify Railties to use with FROM=railtie1,railtie2"
-    task :migrations => :'db:load_config' do
-      to_load = ENV['FROM'].blank? ? :all : ENV['FROM'].split(",").map(&:strip)
+    task migrations: :'db:load_config' do
+      to_load = ENV["FROM"].blank? ? :all : ENV["FROM"].split(",").map(&:strip)
       railties = {}
       Rails.application.migration_railties.each do |railtie|
         next unless to_load == :all || to_load.include?(railtie.railtie_name)
 
-        if railtie.respond_to?(:paths) && (path = railtie.paths['db/migrate'].first)
+        if railtie.respond_to?(:paths) && (path = railtie.paths["db/migrate"].first)
           railties[railtie.railtie_name] = path
         end
       end
@@ -401,7 +374,7 @@ namespace :railties do
       end
 
       ActiveRecord::Migration.copy(ActiveRecord::Tasks::DatabaseTasks.migrations_paths.first, railties,
-                                    :on_skip => on_skip, :on_copy => on_copy)
+                                    on_skip: on_skip, on_copy: on_copy)
     end
   end
 end
diff --git a/activerecord/lib/active_record/railties/jdbcmysql_error.rb b/activerecord/lib/active_record/railties/jdbcmysql_error.rb
deleted file mode 100644
index 6a38211bff..0000000000
--- a/activerecord/lib/active_record/railties/jdbcmysql_error.rb
+++ /dev/null
@@ -1,16 +0,0 @@
-#FIXME Remove if ArJdbcMysql will give.
-module ArJdbcMySQL #:nodoc:
-  class Error < StandardError #:nodoc:
-    attr_accessor :error_number, :sql_state
-
-    def initialize msg
-      super
-      @error_number = nil
-      @sql_state    = nil
-    end
-
-    # Mysql gem compatibility
-    alias_method :errno, :error_number
-    alias_method :error, :message
-  end
-end
diff --git a/activerecord/lib/active_record/readonly_attributes.rb b/activerecord/lib/active_record/readonly_attributes.rb
index ce78f1756d..7bc26993d5 100644
--- a/activerecord/lib/active_record/readonly_attributes.rb
+++ b/activerecord/lib/active_record/readonly_attributes.rb
@@ -1,22 +1,23 @@
+# frozen_string_literal: true
+
 module ActiveRecord
   module ReadonlyAttributes
     extend ActiveSupport::Concern
 
     included do
-      class_attribute :_attr_readonly, instance_accessor: false
-      self._attr_readonly = []
+      class_attribute :_attr_readonly, instance_accessor: false, default: []
     end
 
     module ClassMethods
       # Attributes listed as readonly will be used to create a new record but update operations will
       # ignore these fields.
       def attr_readonly(*attributes)
-        self._attr_readonly = Set.new(attributes.map(&:to_s)) + (self._attr_readonly || [])
+        self._attr_readonly = Set.new(attributes.map(&:to_s)) + (_attr_readonly || [])
       end
 
       # Returns an array of all the attributes that have been specified as readonly.
       def readonly_attributes
-        self._attr_readonly
+        _attr_readonly
       end
     end
   end
diff --git a/activerecord/lib/active_record/reflection.rb b/activerecord/lib/active_record/reflection.rb
index bf398b0d40..a3f8bfd1f1 100644
--- a/activerecord/lib/active_record/reflection.rb
+++ b/activerecord/lib/active_record/reflection.rb
@@ -1,5 +1,7 @@
-require 'thread'
-require 'active_support/core_ext/string/filters'
+# frozen_string_literal: true
+
+require "active_support/core_ext/string/filters"
+require "concurrent/map"
 
 module ActiveRecord
   # = Active Record Reflection
@@ -7,25 +9,24 @@ module ActiveRecord
     extend ActiveSupport::Concern
 
     included do
-      class_attribute :_reflections, instance_writer: false
-      class_attribute :aggregate_reflections, instance_writer: false
-      self._reflections = {}
-      self.aggregate_reflections = {}
+      class_attribute :_reflections, instance_writer: false, default: {}
+      class_attribute :aggregate_reflections, instance_writer: false, default: {}
     end
 
     def self.create(macro, name, scope, options, ar)
-      klass = case macro
-              when :composed_of
-                AggregateReflection
-              when :has_many
-                HasManyReflection
-              when :has_one
-                HasOneReflection
-              when :belongs_to
-                BelongsToReflection
-              else
-                raise "Unsupported Macro: #{macro}"
-              end
+      klass = \
+        case macro
+        when :composed_of
+          AggregateReflection
+        when :has_many
+          HasManyReflection
+        when :has_one
+          HasOneReflection
+        when :belongs_to
+          BelongsToReflection
+        else
+          raise "Unsupported Macro: #{macro}"
+        end
 
       reflection = klass.new(name, scope, options, ar)
       options[:through] ? ThroughReflection.new(reflection) : reflection
@@ -135,8 +136,8 @@ module ActiveRecord
     #         BelongsToReflection
     #         HasAndBelongsToManyReflection
     #     ThroughReflection
-    #       PolymorphicReflection
-    #         RuntimeReflection
+    #     PolymorphicReflection
+    #     RuntimeReflection
     class AbstractReflection # :nodoc:
       def through_reflection?
         false
@@ -152,14 +153,6 @@ module ActiveRecord
         klass.new(attributes, &block)
       end
 
-      def quoted_table_name
-        klass.quoted_table_name
-      end
-
-      def primary_key_type
-        klass.type_for_attribute(klass.primary_key)
-      end
-
       # Returns the class name for the macro.
       #
       # <tt>composed_of :balance, class_name: 'Money'</tt> returns <tt>'Money'</tt>
@@ -170,12 +163,56 @@ module ActiveRecord
 
       JoinKeys = Struct.new(:key, :foreign_key) # :nodoc:
 
-      def join_keys(association_klass)
-        JoinKeys.new(foreign_key, active_record_primary_key)
+      def join_keys
+        @join_keys ||= get_join_keys(klass)
+      end
+
+      # Returns a list of scopes that should be applied for this Reflection
+      # object when querying the database.
+      def scopes
+        scope ? [scope] : []
+      end
+
+      def build_join_constraint(table, foreign_table)
+        key         = join_keys.key
+        foreign_key = join_keys.foreign_key
+
+        constraint = table[key].eq(foreign_table[foreign_key])
+
+        if klass.finder_needs_type_condition?
+          table.create_and([constraint, klass.send(:type_condition, table)])
+        else
+          constraint
+        end
+      end
+
+      def join_scope(table, foreign_klass)
+        predicate_builder = predicate_builder(table)
+        scope_chain_items = join_scopes(table, predicate_builder)
+        klass_scope       = klass_join_scope(table, predicate_builder)
+
+        if type
+          klass_scope.where!(type => foreign_klass.base_class.sti_name)
+        end
+
+        scope_chain_items.inject(klass_scope, &:merge!)
+      end
+
+      def join_scopes(table, predicate_builder) # :nodoc:
+        if scope
+          [scope_for(build_scope(table, predicate_builder))]
+        else
+          []
+        end
+      end
+
+      def klass_join_scope(table, predicate_builder) # :nodoc:
+        relation = build_scope(table, predicate_builder)
+        klass.scope_for_association(relation)
       end
 
       def constraints
-        scope_chain.flatten
+        chain.flat_map(&:scopes)
       end
 
       def counter_cache_column
@@ -247,6 +284,36 @@ module ActiveRecord
       def chain
         collect_join_chain
       end
+
+      def get_join_keys(association_klass)
+        JoinKeys.new(join_primary_key(association_klass), join_foreign_key)
+      end
+
+      def build_scope(table, predicate_builder = predicate_builder(table))
+        Relation.create(klass, table, predicate_builder)
+      end
+
+      def join_primary_key(*)
+        foreign_key
+      end
+
+      def join_foreign_key
+        active_record_primary_key
+      end
+
+      protected
+        def actual_source_reflection # FIXME: this is a horrible name
+          self
+        end
+
+      private
+        def predicate_builder(table)
+          PredicateBuilder.new(TableMetadata.new(klass, table))
+        end
+
+        def primary_key(klass)
+          klass.primary_key || raise(UnknownPrimaryKey.new(klass))
+        end
     end
 
     # Base class for AggregateReflection and AssociationReflection. Objects of
@@ -281,7 +348,6 @@ module ActiveRecord
       end
 
       def autosave=(autosave)
-        @automatic_inverse_of = false
         @options[:autosave] = autosave
         parent_reflection = self.parent_reflection
         if parent_reflection
@@ -293,6 +359,17 @@ module ActiveRecord
       #
       # <tt>composed_of :balance, class_name: 'Money'</tt> returns the Money class
       # <tt>has_many :clients</tt> returns the Client class
+      #
+      #   class Company < ActiveRecord::Base
+      #     has_many :clients
+      #   end
+      #
+      #   Company.reflect_on_association(:clients).klass
+      #   # => Client
+      #
+      # <b>Note:</b> Do not call +klass.new+ or +klass.create+ to instantiate
+      # a new association object. Use +build_association+ or +create_association+
+      # instead. This allows plugins to hook into association object creation.
       def klass
         @klass ||= compute_class(class_name)
       end
@@ -311,14 +388,17 @@ module ActiveRecord
           active_record == other_aggregation.active_record
       end
 
+      def scope_for(relation, owner = nil)
+        relation.instance_exec(owner, &scope) || relation
+      end
+
       private
         def derive_class_name
           name.to_s.camelize
         end
     end
 
-
-    # Holds all the meta-data about an aggregation as it was specified in the
+    # Holds all the metadata about an aggregation as it was specified in the
     # Active Record class.
     class AggregateReflection < MacroReflection #:nodoc:
       def mapping
@@ -327,25 +407,9 @@ module ActiveRecord
       end
     end
 
-    # Holds all the meta-data about an association as it was specified in the
+    # Holds all the metadata about an association as it was specified in the
     # Active Record class.
     class AssociationReflection < MacroReflection #:nodoc:
-      # Returns the target association's class.
-      #
-      #   class Author < ActiveRecord::Base
-      #     has_many :books
-      #   end
-      #
-      #   Author.reflect_on_association(:books).klass
-      #   # => Book
-      #
-      # <b>Note:</b> Do not call +klass.new+ or +klass.create+ to instantiate
-      # a new association object. Use +build_association+ or +create_association+
-      # instead. This allows plugins to hook into association object creation.
-      def klass
-        @klass ||= compute_class(class_name)
-      end
-
       def compute_class(name)
         active_record.send(:compute_type, name)
       end
@@ -355,22 +419,22 @@ module ActiveRecord
 
       def initialize(name, scope, options, active_record)
         super
-        @automatic_inverse_of = nil
         @type         = options[:as] && (options[:foreign_type] || "#{options[:as]}_type")
-        @foreign_type = options[:foreign_type] || "#{name}_type"
+        @foreign_type = options[:polymorphic] && (options[:foreign_type] || "#{name}_type")
         @constructable = calculate_constructable(macro, options)
-        @association_scope_cache = {}
-        @scope_lock = Mutex.new
+        @association_scope_cache = Concurrent::Map.new
+
+        if options[:class_name] && options[:class_name].class == Class
+          raise ArgumentError, "A class was passed to `:class_name` but we are expecting a string."
+        end
       end
 
-      def association_scope_cache(conn, owner)
+      def association_scope_cache(conn, owner, &block)
         key = conn.prepared_statements
         if polymorphic?
           key = [key, owner._read_attribute(@foreign_type)]
         end
-        @association_scope_cache[key] ||= @scope_lock.synchronize {
-          @association_scope_cache[key] ||= yield
-        }
+        @association_scope_cache.compute_if_absent(key) { StatementCache.create(conn, &block) }
       end
 
       def constructable? # :nodoc:
@@ -416,7 +480,7 @@ module ActiveRecord
       alias :check_eager_loadable! :check_preloadable!
 
       def join_id_for(owner) # :nodoc:
-        owner[active_record_primary_key]
+        owner[join_foreign_key]
       end
 
       def through_reflection
@@ -443,12 +507,6 @@ module ActiveRecord
         false
       end
 
-      # An array of arrays of scopes. Each item in the outside array corresponds to a reflection
-      # in the #chain.
-      def scope_chain
-        scope ? [[scope]] : [[]]
-      end
-
       def has_scope?
         scope
       end
@@ -505,7 +563,7 @@ module ActiveRecord
       end
 
       VALID_AUTOMATIC_INVERSE_MACROS = [:has_many, :has_one, :belongs_to]
-      INVALID_AUTOMATIC_INVERSE_OPTIONS = [:conditions, :through, :polymorphic, :foreign_key]
+      INVALID_AUTOMATIC_INVERSE_OPTIONS = [:conditions, :through, :foreign_key]
 
       def add_as_source(seed)
         seed
@@ -519,11 +577,9 @@ module ActiveRecord
         seed + [self]
       end
 
-      protected
-
-        def actual_source_reflection # FIXME: this is a horrible name
-          self
-        end
+      def extensions
+        Array(options[:extend])
+      end
 
       private
 
@@ -533,18 +589,16 @@ module ActiveRecord
 
         # Attempts to find the inverse association name automatically.
         # If it cannot find a suitable inverse association name, it returns
-        # nil.
+        # +nil+.
         def inverse_name
-          options.fetch(:inverse_of) do
-            if @automatic_inverse_of == false
-              nil
-            else
-              @automatic_inverse_of ||= automatic_inverse_of
-            end
+          unless defined?(@inverse_name)
+            @inverse_name = options.fetch(:inverse_of) { automatic_inverse_of }
           end
+
+          @inverse_name
         end
 
-        # returns either false or the inverse association name that it finds.
+        # returns either +nil+ or the inverse association name that it finds.
         def automatic_inverse_of
           if can_find_inverse_of_automatically?(self)
             inverse_name = ActiveSupport::Inflector.underscore(options[:as] || active_record.name.demodulize).to_sym
@@ -561,8 +615,6 @@ module ActiveRecord
               return inverse_name
             end
           end
-
-          false
         end
 
         # Checks if the inverse reflection that is returned from the
@@ -574,7 +626,7 @@ module ActiveRecord
         # from calling +klass+, +reflection+ will already be set to false.
         def valid_inverse_reflection?(reflection)
           reflection &&
-            klass.name == reflection.active_record.name &&
+            klass <= reflection.active_record &&
             can_find_inverse_of_automatically?(reflection)
         end
 
@@ -582,9 +634,8 @@ module ActiveRecord
         # us from being able to guess the inverse automatically. First, the
         # <tt>inverse_of</tt> option cannot be set to false. Second, we must
         # have <tt>has_many</tt>, <tt>has_one</tt>, <tt>belongs_to</tt> associations.
-        # Third, we must not have options such as <tt>:polymorphic</tt> or
-        # <tt>:foreign_key</tt> which prevent us from correctly guessing the
-        # inverse association.
+        # Third, we must not have options such as <tt>:foreign_key</tt>
+        # which prevent us from correctly guessing the inverse association.
         #
         # Anything with a scope can additionally ruin our attempt at finding an
         # inverse, so we exclude reflections with scopes.
@@ -614,10 +665,6 @@ module ActiveRecord
         def derive_join_table
           ModelSchema.derive_join_table_name active_record.table_name, klass.table_name
         end
-
-        def primary_key(klass)
-          klass.primary_key || raise(UnknownPrimaryKey.new(klass))
-        end
     end
 
     class HasManyReflection < AssociationReflection # :nodoc:
@@ -632,6 +679,10 @@ module ActiveRecord
           Associations::HasManyAssociation
         end
       end
+
+      def association_primary_key(klass = nil)
+        primary_key(klass || self.klass)
+      end
     end
 
     class HasOneReflection < AssociationReflection # :nodoc:
@@ -667,13 +718,12 @@ module ActiveRecord
         end
       end
 
-      def join_keys(association_klass)
-        key = polymorphic? ? association_primary_key(association_klass) : association_primary_key
-        JoinKeys.new(key, foreign_key)
+      def join_primary_key(klass = nil)
+        polymorphic? ? association_primary_key(klass) : association_primary_key
       end
 
-      def join_id_for(owner) # :nodoc:
-        owner[foreign_key]
+      def join_foreign_key
+        foreign_key
       end
 
       private
@@ -684,10 +734,6 @@ module ActiveRecord
     end
 
     class HasAndBelongsToManyReflection < AssociationReflection # :nodoc:
-      def initialize(name, scope, options, active_record)
-        super
-      end
-
       def macro; :has_and_belongs_to_many; end
 
       def collection?
@@ -695,16 +741,15 @@ module ActiveRecord
       end
     end
 
-    # Holds all the meta-data about a :through association as it was specified
+    # Holds all the metadata about a :through association as it was specified
     # in the Active Record class.
     class ThroughReflection < AbstractReflection #:nodoc:
-      attr_reader :delegate_reflection
-      delegate :foreign_key, :foreign_type, :association_foreign_key,
-               :active_record_primary_key, :type, :to => :source_reflection
+      delegate :foreign_key, :foreign_type, :association_foreign_key, :join_id_for,
+               :active_record_primary_key, :type, :get_join_keys, to: :source_reflection
 
       def initialize(delegate_reflection)
         @delegate_reflection = delegate_reflection
-        @klass         = delegate_reflection.options[:anonymous_class]
+        @klass = delegate_reflection.options[:anonymous_class]
         @source_reflection_name = delegate_reflection.options[:source]
       end
 
@@ -782,45 +827,12 @@ module ActiveRecord
         through_reflection.clear_association_scope_cache
       end
 
-      # Consider the following example:
-      #
-      #   class Person
-      #     has_many :articles
-      #     has_many :comment_tags, through: :articles
-      #   end
-      #
-      #   class Article
-      #     has_many :comments
-      #     has_many :comment_tags, through: :comments, source: :tags
-      #   end
-      #
-      #   class Comment
-      #     has_many :tags
-      #   end
-      #
-      # There may be scopes on Person.comment_tags, Article.comment_tags and/or Comment.tags,
-      # but only Comment.tags will be represented in the #chain. So this method creates an array
-      # of scopes corresponding to the chain.
-      def scope_chain
-        @scope_chain ||= begin
-          scope_chain = source_reflection.scope_chain.map(&:dup)
-
-          # Add to it the scope from this reflection (if any)
-          scope_chain.first << scope if scope
-
-          through_scope_chain = through_reflection.scope_chain.map(&:dup)
-
-          if options[:source_type]
-            type = foreign_type
-            source_type = options[:source_type]
-            through_scope_chain.first << lambda { |object|
-              where(type => source_type)
-            }
-          end
+      def scopes
+        source_reflection.scopes + super
+      end
 
-          # Recursively fill out the rest of the array from the through reflection
-          scope_chain + through_scope_chain
-        end
+      def join_scopes(table, predicate_builder) # :nodoc:
+        source_reflection.join_scopes(table, predicate_builder) + super
       end
 
       def has_scope?
@@ -829,10 +841,6 @@ module ActiveRecord
           through_reflection.has_scope?
       end
 
-      def join_keys(association_klass)
-        source_reflection.join_keys(association_klass)
-      end
-
       # A through association is nested if there would be more than one join table
       def nested?
         source_reflection.through_reflection? || through_reflection.through_reflection?
@@ -871,15 +879,13 @@ module ActiveRecord
         }
 
         if names.length > 1
-          example_options = options.dup
-          example_options[:source] = source_reflection_names.first
-          ActiveSupport::Deprecation.warn \
-            "Ambiguous source reflection for through association. Please " \
-            "specify a :source directive on your declaration like:\n" \
-            "\n" \
-            "  class #{active_record.name} < ActiveRecord::Base\n" \
-            "    #{macro} :#{name}, #{example_options}\n" \
-            "  end"
+          raise AmbiguousSourceReflectionForThroughAssociation.new(
+            active_record.name,
+            macro,
+            name,
+            options,
+            source_reflection_names
+          )
         end
 
         @source_reflection_name = names.first
@@ -893,10 +899,6 @@ module ActiveRecord
         through_reflection.options
       end
 
-      def join_id_for(owner) # :nodoc:
-        source_reflection.join_id_for(owner)
-      end
-
       def check_validity!
         if through_reflection.nil?
           raise HasManyThroughAssociationNotFoundError.new(active_record.name, self)
@@ -926,6 +928,14 @@ module ActiveRecord
           raise HasOneThroughCantAssociateThroughCollection.new(active_record.name, self, through_reflection)
         end
 
+        if parent_reflection.nil?
+          reflections = active_record.reflections.keys.map(&:to_sym)
+
+          if reflections.index(through_reflection.name) > reflections.index(name)
+            raise HasManyThroughOrderError.new(active_record.name, self, through_reflection)
+          end
+        end
+
         check_validity_of_inverse!
       end
 
@@ -947,28 +957,27 @@ module ActiveRecord
         collect_join_reflections(seed + [self])
       end
 
-      def collect_join_reflections(seed)
-        a = source_reflection.add_as_source seed
-        if options[:source_type]
-          through_reflection.add_as_polymorphic_through self, a
-        else
-          through_reflection.add_as_through a
-        end
-      end
-
+      # TODO Change this to private once we've dropped Ruby 2.2 support.
+      # Workaround for Ruby 2.2 "private attribute?" warning.
       protected
+        attr_reader :delegate_reflection
 
         def actual_source_reflection # FIXME: this is a horrible name
-          source_reflection.send(:actual_source_reflection)
+          source_reflection.actual_source_reflection
         end
 
-        def primary_key(klass)
-          klass.primary_key || raise(UnknownPrimaryKey.new(klass))
+      private
+        def collect_join_reflections(seed)
+          a = source_reflection.add_as_source seed
+          if options[:source_type]
+            through_reflection.add_as_polymorphic_through self, a
+          else
+            through_reflection.add_as_through a
+          end
         end
 
         def inverse_name; delegate_reflection.send(:inverse_name); end
 
-      private
         def derive_class_name
           # get the class_name of the belongs_to association of the through reflection
           options[:source_type] || source_reflection.class_name
@@ -978,52 +987,35 @@ module ActiveRecord
           public_instance_methods
 
         delegate(*delegate_methods, to: :delegate_reflection)
-
     end
 
-    class PolymorphicReflection < ThroughReflection # :nodoc:
+    class PolymorphicReflection < AbstractReflection # :nodoc:
+      delegate :klass, :scope, :plural_name, :type, :get_join_keys, :scope_for, to: :@reflection
+
       def initialize(reflection, previous_reflection)
         @reflection = reflection
         @previous_reflection = previous_reflection
       end
 
-      def klass
-        @reflection.klass
-      end
-
-      def scope
-        @reflection.scope
-      end
-
-      def table_name
-        @reflection.table_name
-      end
-
-      def plural_name
-        @reflection.plural_name
-      end
-
-      def join_keys(association_klass)
-        @reflection.join_keys(association_klass)
-      end
-
-      def type
-        @reflection.type
+      def join_scopes(table, predicate_builder) # :nodoc:
+        scopes = @previous_reflection.join_scopes(table, predicate_builder) + super
+        scopes << build_scope(table, predicate_builder).instance_exec(nil, &source_type_scope)
       end
 
       def constraints
-        @reflection.constraints + [source_type_info]
+        @reflection.constraints + [source_type_scope]
       end
 
-      def source_type_info
-        type = @previous_reflection.foreign_type
-        source_type = @previous_reflection.options[:source_type]
-        lambda { |object| where(type => source_type) }
-      end
+      private
+        def source_type_scope
+          type = @previous_reflection.foreign_type
+          source_type = @previous_reflection.options[:source_type]
+          lambda { |object| where(type => source_type) }
+        end
     end
 
-    class RuntimeReflection < PolymorphicReflection # :nodoc:
-      attr_accessor :next
+    class RuntimeReflection < AbstractReflection # :nodoc:
+      delegate :scope, :type, :constraints, :get_join_keys, to: :@reflection
 
       def initialize(reflection, association)
         @reflection = reflection
@@ -1034,24 +1026,8 @@ module ActiveRecord
         @association.klass
       end
 
-      def table_name
-        klass.table_name
-      end
-
-      def constraints
-        @reflection.constraints
-      end
-
-      def source_type_info
-        @reflection.source_type_info
-      end
-
-      def alias_candidate(name)
-        "#{plural_name}_#{name}_join"
-      end
-
-      def alias_name
-        Arel::Table.new(table_name)
+      def aliased_table
+        @aliased_table ||= Arel::Table.new(table_name, type_caster: klass.type_caster)
       end
 
       def all_includes; yield; end
diff --git a/activerecord/lib/active_record/relation.rb b/activerecord/lib/active_record/relation.rb
index 7a1552856b..4df3864d07 100644
--- a/activerecord/lib/active_record/relation.rb
+++ b/activerecord/lib/active_record/relation.rb
@@ -1,16 +1,16 @@
-require "arel/collectors/bind"
+# frozen_string_literal: true
 
 module ActiveRecord
   # = Active Record \Relation
   class Relation
     MULTI_VALUE_METHODS  = [:includes, :eager_load, :preload, :select, :group,
-                            :order, :joins, :left_joins, :left_outer_joins, :references,
+                            :order, :joins, :left_outer_joins, :references,
                             :extending, :unscope]
 
     SINGLE_VALUE_METHODS = [:limit, :offset, :lock, :readonly, :reordering,
-                            :reverse_order, :distinct, :create_with]
+                            :reverse_order, :distinct, :create_with, :skip_query_cache]
     CLAUSE_METHODS = [:where, :having, :from]
-    INVALID_METHODS_FOR_DELETE_ALL = [:limit, :distinct, :offset, :group, :having]
+    INVALID_METHODS_FOR_DELETE_ALL = [:distinct, :group, :having]
 
     VALUE_METHODS = MULTI_VALUE_METHODS + SINGLE_VALUE_METHODS + CLAUSE_METHODS
 
@@ -20,6 +20,7 @@ module ActiveRecord
     attr_reader :table, :klass, :loaded, :predicate_builder
     alias :model :klass
     alias :loaded? :loaded
+    alias :locked? :lock_value
 
     def initialize(klass, table, predicate_builder, values = {})
       @klass  = klass
@@ -31,80 +32,10 @@ module ActiveRecord
     end
 
     def initialize_copy(other)
-      # This method is a hot spot, so for now, use Hash[] to dup the hash.
-      #   https://bugs.ruby-lang.org/issues/7166
-      @values        = Hash[@values]
+      @values = @values.dup
       reset
     end
 
-    def insert(values) # :nodoc:
-      primary_key_value = nil
-
-      if primary_key && Hash === values
-        primary_key_value = values[values.keys.find { |k|
-          k.name == primary_key
-        }]
-
-        if !primary_key_value && klass.prefetch_primary_key?
-          primary_key_value = klass.next_sequence_value
-          values[arel_attribute(klass.primary_key)] = primary_key_value
-        end
-      end
-
-      im = arel.create_insert
-      im.into @table
-
-      substitutes, binds = substitute_values values
-
-      if values.empty? # empty insert
-        im.values = Arel.sql(connection.empty_insert_statement_value)
-      else
-        im.insert substitutes
-      end
-
-      @klass.connection.insert(
-        im,
-        'SQL',
-        primary_key,
-        primary_key_value,
-        nil,
-        binds)
-    end
-
-    def _update_record(values, id, id_was) # :nodoc:
-      substitutes, binds = substitute_values values
-
-      scope = @klass.unscoped
-
-      if @klass.finder_needs_type_condition?
-        scope.unscope!(where: @klass.inheritance_column)
-      end
-
-      relation = scope.where(@klass.primary_key => (id_was || id))
-      bvs = binds + relation.bound_attributes
-      um = relation
-        .arel
-        .compile_update(substitutes, @klass.primary_key)
-
-      @klass.connection.update(
-        um,
-        'SQL',
-        bvs,
-      )
-    end
-
-    def substitute_values(values) # :nodoc:
-      binds = []
-      substitutes = []
-
-      values.each do |arel_attr, value|
-        binds.push QueryAttribute.new(arel_attr.name, value, klass.type_for_attribute(arel_attr.name))
-        substitutes.push [arel_attr, Arel::Nodes::BindParam.new]
-      end
-
-      [substitutes, binds]
-    end
-
     def arel_attribute(name) # :nodoc:
       klass.arel_attribute(name, table)
     end
@@ -121,8 +52,8 @@ module ActiveRecord
     #
     #   user = users.new { |user| user.name = 'Oscar' }
     #   user.name # => Oscar
-    def new(*args, &block)
-      scoping { @klass.new(*args, &block) }
+    def new(attributes = nil, &block)
+      scoping { klass.new(scope_for_create(attributes), &block) }
     end
 
     alias build new
@@ -146,8 +77,12 @@ module ActiveRecord
     #
     #   users.create(name: nil) # validation on name
     #   # => #<User id: nil, name: nil, ...>
-    def create(*args, &block)
-      scoping { @klass.create(*args, &block) }
+    def create(attributes = nil, &block)
+      if attributes.is_a?(Array)
+        attributes.collect { |attr| create(attr, &block) }
+      else
+        scoping { klass.create(scope_for_create(attributes), &block) }
+      end
     end
 
     # Similar to #create, but calls
@@ -156,8 +91,12 @@ module ActiveRecord
     #
     # Expects arguments in the same format as
     # {ActiveRecord::Base.create!}[rdoc-ref:Persistence::ClassMethods#create!].
-    def create!(*args, &block)
-      scoping { @klass.create!(*args, &block) }
+    def create!(attributes = nil, &block)
+      if attributes.is_a?(Array)
+        attributes.collect { |attr| create!(attr, &block) }
+      else
+        scoping { klass.create!(scope_for_create(attributes), &block) }
+      end
     end
 
     def first_or_create(attributes = nil, &block) # :nodoc:
@@ -247,14 +186,14 @@ module ActiveRecord
     # Please see further details in the
     # {Active Record Query Interface guide}[http://guides.rubyonrails.org/active_record_querying.html#running-explain].
     def explain
-      #TODO: Fix for binds.
       exec_explain(collecting_queries_for_explain { exec_queries })
     end
 
     # Converts relation objects to Array.
-    def to_a
+    def to_ary
       records.dup
     end
+    alias to_a to_ary
 
     def records # :nodoc:
       load
@@ -266,10 +205,6 @@ module ActiveRecord
       coder.represent_seq(nil, records)
     end
 
-    def as_json(options = nil) #:nodoc:
-      records.as_json(options)
-    end
-
     # Returns size of the records.
     def size
       loaded? ? @records.length : count(:all)
@@ -278,8 +213,7 @@ module ActiveRecord
     # Returns true if there are no records.
     def empty?
       return @records.empty? if loaded?
-
-      limit_value == 0 || !exists?
+      !exists?
     end
 
     # Returns true if there are no records.
@@ -342,7 +276,7 @@ module ActiveRecord
     # Please check unscoped if you want to remove all previous scopes (including
     # the default_scope) during the execution of a block.
     def scoping
-      previous, klass.current_scope = klass.current_scope, self
+      previous, klass.current_scope = klass.current_scope(true), self
       yield
     ensure
       klass.current_scope = previous
@@ -367,15 +301,23 @@ module ActiveRecord
     #
     #   # Update all books that match conditions, but limit it to 5 ordered by date
     #   Book.where('title LIKE ?', '%Rails%').order(:created_at).limit(5).update_all(author: 'David')
+    #
+    #   # Update all invoices and set the number column to its id value.
+    #   Invoice.update_all('number = id')
     def update_all(updates)
       raise ArgumentError, "Empty list of attributes to change" if updates.blank?
 
+      if eager_loading?
+        relation = apply_join_dependency
+        return relation.update_all(updates)
+      end
+
       stmt = Arel::UpdateManager.new
 
-      stmt.set Arel.sql(@klass.send(:sanitize_sql_for_assignment, updates))
+      stmt.set Arel.sql(@klass.sanitize_sql_for_assignment(updates))
       stmt.table(table)
 
-      if joins_values.any?
+      if has_join_values? || offset_value
         @klass.connection.join_to_update(stmt, arel, arel_attribute(primary_key))
       else
         stmt.key = arel_attribute(primary_key)
@@ -384,52 +326,7 @@ module ActiveRecord
         stmt.wheres = arel.constraints
       end
 
-      @klass.connection.update stmt, 'SQL', bound_attributes
-    end
-
-    # Updates an object (or multiple objects) and saves it to the database, if validations pass.
-    # The resulting object is returned whether the object was saved successfully to the database or not.
-    #
-    # ==== Parameters
-    #
-    # * +id+ - This should be the id or an array of ids to be updated.
-    # * +attributes+ - This should be a hash of attributes or an array of hashes.
-    #
-    # ==== Examples
-    #
-    #   # Updates one record
-    #   Person.update(15, user_name: 'Samuel', group: 'expert')
-    #
-    #   # Updates multiple records
-    #   people = { 1 => { "first_name" => "David" }, 2 => { "first_name" => "Jeremy" } }
-    #   Person.update(people.keys, people.values)
-    #
-    #   # Updates multiple records from the result of a relation
-    #   people = Person.where(group: 'expert')
-    #   people.update(group: 'masters')
-    #
-    # Note: Updating a large number of records will run an
-    # UPDATE query for each record, which may cause a performance
-    # issue. So if it is not needed to run callbacks for each update, it is
-    # preferred to use #update_all for updating all records using
-    # a single query.
-    def update(id = :all, attributes)
-      if id.is_a?(Array)
-        id.map.with_index { |one_id, idx| update(one_id, attributes[idx]) }
-      elsif id == :all
-        records.each { |record| record.update(attributes) }
-      else
-        if ActiveRecord::Base === id
-          id = id.id
-          ActiveSupport::Deprecation.warn(<<-MSG.squish)
-            You are passing an instance of ActiveRecord::Base to `update`.
-            Please pass the id of the object by calling `.id`.
-          MSG
-        end
-        object = find(id)
-        object.update(attributes)
-        object
-      end
+      @klass.connection.update stmt, "#{@klass} Update All"
     end
 
     # Destroys the records by instantiating each
@@ -448,43 +345,8 @@ module ActiveRecord
     # ==== Examples
     #
     #   Person.where(age: 0..18).destroy_all
-    def destroy_all(conditions = nil)
-      if conditions
-        ActiveSupport::Deprecation.warn(<<-MESSAGE.squish)
-          Passing conditions to destroy_all is deprecated and will be removed in Rails 5.1.
-          To achieve the same use where(conditions).destroy_all.
-        MESSAGE
-        where(conditions).destroy_all
-      else
-        records.each(&:destroy).tap { reset }
-      end
-    end
-
-    # Destroy an object (or multiple objects) that has the given id. The object is instantiated first,
-    # therefore all callbacks and filters are fired off before the object is deleted. This method is
-    # less efficient than #delete but allows cleanup methods and other actions to be run.
-    #
-    # This essentially finds the object (or multiple objects) with the given id, creates a new object
-    # from the attributes, and then calls destroy on it.
-    #
-    # ==== Parameters
-    #
-    # * +id+ - Can be either an Integer or an Array of Integers.
-    #
-    # ==== Examples
-    #
-    #   # Destroy a single object
-    #   Todo.destroy(1)
-    #
-    #   # Destroy multiple objects
-    #   todos = [1,2,3]
-    #   Todo.destroy(todos)
-    def destroy(id)
-      if id.is_a?(Array)
-        id.map { |one_id| destroy(one_id) }
-      else
-        find(id).destroy
-      end
+    def destroy_all
+      records.each(&:destroy).tap { reset }
     end
 
     # Deletes the records without instantiating the records
@@ -503,66 +365,35 @@ module ActiveRecord
     #
     # If an invalid method is supplied, #delete_all raises an ActiveRecordError:
     #
-    #   Post.limit(100).delete_all
-    #   # => ActiveRecord::ActiveRecordError: delete_all doesn't support limit
-    def delete_all(conditions = nil)
-      invalid_methods = INVALID_METHODS_FOR_DELETE_ALL.select { |method|
-        if MULTI_VALUE_METHODS.include?(method)
-          send("#{method}_values").any?
-        elsif SINGLE_VALUE_METHODS.include?(method)
-          send("#{method}_value")
-        elsif CLAUSE_METHODS.include?(method)
-          send("#{method}_clause").any?
-        end
-      }
+    #   Post.distinct.delete_all
+    #   # => ActiveRecord::ActiveRecordError: delete_all doesn't support distinct
+    def delete_all
+      invalid_methods = INVALID_METHODS_FOR_DELETE_ALL.select do |method|
+        value = get_value(method)
+        SINGLE_VALUE_METHODS.include?(method) ? value : value.any?
+      end
       if invalid_methods.any?
         raise ActiveRecordError.new("delete_all doesn't support #{invalid_methods.join(', ')}")
       end
 
-      if conditions
-        ActiveSupport::Deprecation.warn(<<-MESSAGE.squish)
-          Passing conditions to delete_all is deprecated and will be removed in Rails 5.1.
-          To achieve the same use where(conditions).delete_all.
-        MESSAGE
-        where(conditions).delete_all
-      else
-        stmt = Arel::DeleteManager.new
-        stmt.from(table)
-
-        if joins_values.any?
-          @klass.connection.join_to_delete(stmt, arel, arel_attribute(primary_key))
-        else
-          stmt.wheres = arel.constraints
-        end
+      if eager_loading?
+        relation = apply_join_dependency
+        return relation.delete_all
+      end
 
-        affected = @klass.connection.delete(stmt, 'SQL', bound_attributes)
+      stmt = Arel::DeleteManager.new
+      stmt.from(table)
 
-        reset
-        affected
+      if has_join_values? || has_limit_or_offset?
+        @klass.connection.join_to_delete(stmt, arel, arel_attribute(primary_key))
+      else
+        stmt.wheres = arel.constraints
       end
-    end
 
-    # Deletes the row with a primary key matching the +id+ argument, using a
-    # SQL +DELETE+ statement, and returns the number of rows deleted. Active
-    # Record objects are not instantiated, so the object's callbacks are not
-    # executed, including any <tt>:dependent</tt> association options.
-    #
-    # You can delete multiple rows at once by passing an Array of <tt>id</tt>s.
-    #
-    # Note: Although it is often much faster than the alternative,
-    # #destroy, skipping callbacks might bypass business logic in
-    # your application that ensures referential integrity or performs other
-    # essential jobs.
-    #
-    # ==== Examples
-    #
-    #   # Delete a single row
-    #   Todo.delete(1)
-    #
-    #   # Delete multiple rows
-    #   Todo.delete([2,3,4])
-    def delete(id_or_array)
-      where(primary_key => id_or_array).delete_all
+      affected = @klass.connection.delete(stmt, "#{@klass} Destroy")
+
+      reset
+      affected
     end
 
     # Causes the records to be loaded from the database if they have not
@@ -571,8 +402,8 @@ module ActiveRecord
     # return value is the relation itself, not the records.
     #
     #   Post.where(published: true).load # => #<ActiveRecord::Relation>
-    def load
-      exec_queries unless loaded?
+    def load(&block)
+      exec_queries(&block) unless loaded?
 
       self
     end
@@ -584,8 +415,7 @@ module ActiveRecord
     end
 
     def reset
-      @last = @to_sql = @order_clause = @scope_for_create = @arel = @loaded = nil
-      @should_eager_load = @join_dependency = nil
+      @to_sql = @arel = @loaded = @should_eager_load = nil
       @records = [].freeze
       @offsets = {}
       self
@@ -597,19 +427,16 @@ module ActiveRecord
     #   # => SELECT "users".* FROM "users"  WHERE "users"."name" = 'Oscar'
     def to_sql
       @to_sql ||= begin
-                    relation   = self
-                    connection = klass.connection
-                    visitor    = connection.visitor
+                    relation = self
 
                     if eager_loading?
-                      find_with_associations { |rel| relation = rel }
+                      find_with_associations { |rel, _| relation = rel }
                     end
 
-                    binds = relation.bound_attributes
-                    binds = connection.prepare_binds_for_database(binds)
-                    binds.map! { |value| connection.quote(value) }
-                    collect = visitor.accept(relation.arel.ast, Arel::Collectors::Bind.new)
-                    collect.substitute_binds(binds).join
+                    conn = klass.connection
+                    conn.unprepared_statement {
+                      conn.to_sql(relation.arel)
+                    }
                   end
     end
 
@@ -617,12 +444,14 @@ module ActiveRecord
     #
     #   User.where(name: 'Oscar').where_values_hash
     #   # => {name: "Oscar"}
-    def where_values_hash(relation_table_name = table_name)
+    def where_values_hash(relation_table_name = klass.table_name)
       where_clause.to_h(relation_table_name)
     end
 
-    def scope_for_create
-      @scope_for_create ||= where_values_hash.merge(create_with_value)
+    def scope_for_create(attributes = nil)
+      scope = where_values_hash.merge!(create_with_value.stringify_keys)
+      scope.merge!(attributes) if attributes
+      scope
     end
 
     # Returns true if relation needs eager loading.
@@ -640,15 +469,6 @@ module ActiveRecord
       includes_values & joins_values
     end
 
-    # {#uniq}[rdoc-ref:QueryMethods#uniq] and
-    # {#uniq!}[rdoc-ref:QueryMethods#uniq!] are silently deprecated.
-    # #uniq_value delegates to #distinct_value to maintain backwards compatibility.
-    # Use #distinct_value instead.
-    def uniq_value
-      distinct_value
-    end
-    deprecate uniq_value: :distinct_value
-
     # Compares two relations for equality.
     def ==(other)
       case other
@@ -662,7 +482,7 @@ module ActiveRecord
     end
 
     def pretty_print(q)
-      q.pp(self.records)
+      q.pp(records)
     end
 
     # Returns true if relation is blank.
@@ -671,16 +491,31 @@ module ActiveRecord
     end
 
     def values
-      Hash[@values]
+      @values.dup
     end
 
     def inspect
-      entries = records.take([limit_value, 11].compact.min).map!(&:inspect)
-      entries[10] = '...' if entries.size == 11
+      subject = loaded? ? records : self
+      entries = subject.take([limit_value, 11].compact.min).map!(&:inspect)
+
+      entries[10] = "..." if entries.size == 11
 
       "#<#{self.class.name} [#{entries.join(', ')}]>"
     end
 
+    def empty_scope? # :nodoc:
+      @values == klass.unscoped.values
+    end
+
+    def has_limit_or_offset? # :nodoc:
+      limit_value || offset_value
+    end
+
+    def alias_tracker(joins = [], aliases = nil) # :nodoc:
+      joins += [aliases] if aliases
+      ActiveRecord::Associations::AliasTracker.create(connection, table.name, joins)
+    end
+
     protected
 
       def load_records(records)
@@ -690,48 +525,77 @@ module ActiveRecord
 
     private
 
-    def exec_queries
-      @records = eager_loading? ? find_with_associations.freeze : @klass.find_by_sql(arel, bound_attributes).freeze
-
-      preload = preload_values
-      preload +=  includes_values unless eager_loading?
-      preloader = build_preloader
-      preload.each do |associations|
-        preloader.preload @records, associations
+      def has_join_values?
+        joins_values.any? || left_outer_joins_values.any?
       end
 
-      @records.each(&:readonly!) if readonly_value
-
-      @loaded = true
-      @records
-    end
-
-    def build_preloader
-      ActiveRecord::Associations::Preloader.new
-    end
+      def exec_queries(&block)
+        skip_query_cache_if_necessary do
+          @records =
+            if eager_loading?
+              find_with_associations do |relation, join_dependency|
+                if ActiveRecord::NullRelation === relation
+                  []
+                else
+                  rows = connection.select_all(relation.arel, "SQL")
+                  join_dependency.instantiate(rows, &block)
+                end.freeze
+              end
+            else
+              klass.find_by_sql(arel, &block).freeze
+            end
+
+          preload = preload_values
+          preload += includes_values unless eager_loading?
+          preloader = nil
+          preload.each do |associations|
+            preloader ||= build_preloader
+            preloader.preload @records, associations
+          end
+
+          @records.each(&:readonly!) if readonly_value
+
+          @loaded = true
+          @records
+        end
+      end
 
-    def references_eager_loaded_tables?
-      joined_tables = arel.join_sources.map do |join|
-        if join.is_a?(Arel::Nodes::StringJoin)
-          tables_in_string(join.left)
+      def skip_query_cache_if_necessary
+        if skip_query_cache_value
+          uncached do
+            yield
+          end
         else
-          [join.left.table_name, join.left.table_alias]
+          yield
         end
       end
 
-      joined_tables += [table.name, table.table_alias]
+      def build_preloader
+        ActiveRecord::Associations::Preloader.new
+      end
+
+      def references_eager_loaded_tables?
+        joined_tables = arel.join_sources.map do |join|
+          if join.is_a?(Arel::Nodes::StringJoin)
+            tables_in_string(join.left)
+          else
+            [join.left.table_name, join.left.table_alias]
+          end
+        end
 
-      # always convert table names to downcase as in Oracle quoted table names are in uppercase
-      joined_tables = joined_tables.flatten.compact.map(&:downcase).uniq
+        joined_tables += [table.name, table.table_alias]
 
-      (references_values - joined_tables).any?
-    end
+        # always convert table names to downcase as in Oracle quoted table names are in uppercase
+        joined_tables = joined_tables.flatten.compact.map(&:downcase).uniq
 
-    def tables_in_string(string)
-      return [] if string.blank?
-      # always convert table names to downcase as in Oracle quoted table names are in uppercase
-      # ignore raw_sql_ that is used by Oracle adapter as alias for limit/offset subqueries
-      string.scan(/([a-zA-Z_][.\w]+).?\./).flatten.map(&:downcase).uniq - ['raw_sql_']
-    end
+        (references_values - joined_tables).any?
+      end
+
+      def tables_in_string(string)
+        return [] if string.blank?
+        # always convert table names to downcase as in Oracle quoted table names are in uppercase
+        # ignore raw_sql_ that is used by Oracle adapter as alias for limit/offset subqueries
+        string.scan(/([a-zA-Z_][.\w]+).?\./).flatten.map(&:downcase).uniq - ["raw_sql_"]
+      end
   end
 end
diff --git a/activerecord/lib/active_record/relation/batches.rb b/activerecord/lib/active_record/relation/batches.rb
index 3639625722..561869017a 100644
--- a/activerecord/lib/active_record/relation/batches.rb
+++ b/activerecord/lib/active_record/relation/batches.rb
@@ -1,8 +1,10 @@
+# frozen_string_literal: true
+
 require "active_record/relation/batches/batch_enumerator"
 
 module ActiveRecord
   module Batches
-    ORDER_OR_LIMIT_IGNORED_MESSAGE = "Scoped order and limit are ignored, it's forced to be batch order and batch size."
+    ORDER_IGNORE_MESSAGE = "Scoped order is ignored, it's forced to be batch order."
 
     # Looping through a collection of records from the database
     # (using the Scoping::Named::ClassMethods.all method, for example)
@@ -30,19 +32,28 @@ module ActiveRecord
     #   end
     #
     # ==== Options
-    # * <tt>:batch_size</tt> - Specifies the size of the batch. Default to 1000.
+    # * <tt>:batch_size</tt> - Specifies the size of the batch. Defaults to 1000.
     # * <tt>:start</tt> - Specifies the primary key value to start from, inclusive of the value.
     # * <tt>:finish</tt> - Specifies the primary key value to end at, inclusive of the value.
     # * <tt>:error_on_ignore</tt> - Overrides the application config to specify if an error should be raised when
-    #                               the order and limit have to be ignored due to batching.
+    #   an order is present in the relation.
+    #
+    # Limits are honored, and if present there is no requirement for the batch
+    # size: it can be less than, equal to, or greater than the limit.
+    #
+    # The options +start+ and +finish+ are especially useful if you want
+    # multiple workers dealing with the same processing queue. You can make
+    # worker 1 handle all the records between id 1 and 9999 and worker 2
+    # handle from 10000 and beyond by setting the +:start+ and +:finish+
+    # option on each worker.
     #
-    # This is especially useful if you want multiple workers dealing with
-    # the same processing queue. You can make worker 1 handle all the records
-    # between id 0 and 10,000 and worker 2 handle from 10,000 and beyond
-    # (by setting the +:start+ and +:finish+ option on each worker).
+    #   # In worker 1, let's process until 9999 records.
+    #   Person.find_each(finish: 9_999) do |person|
+    #     person.party_all_night!
+    #   end
     #
-    #   # Let's process for a batch of 2000 records, skipping the first 2000 rows
-    #   Person.find_each(start: 2000, batch_size: 2000) do |person|
+    #   # In worker 2, let's process from record 10_000 and onwards.
+    #   Person.find_each(start: 10_000) do |person|
     #     person.party_all_night!
     #   end
     #
@@ -51,8 +62,8 @@ module ActiveRecord
     # work. This also means that this method only works when the primary key is
     # orderable (e.g. an integer or string).
     #
-    # NOTE: You can't set the limit either, that's used to control
-    # the batch sizes.
+    # NOTE: By its nature, batch processing is subject to race conditions if
+    # other processes are modifying the database.
     def find_each(start: nil, finish: nil, batch_size: 1000, error_on_ignore: nil)
       if block_given?
         find_in_batches(start: start, finish: finish, batch_size: batch_size, error_on_ignore: error_on_ignore) do |records|
@@ -85,19 +96,23 @@ module ActiveRecord
     # To be yielded each record one by one, use #find_each instead.
     #
     # ==== Options
-    # * <tt>:batch_size</tt> - Specifies the size of the batch. Default to 1000.
+    # * <tt>:batch_size</tt> - Specifies the size of the batch. Defaults to 1000.
     # * <tt>:start</tt> - Specifies the primary key value to start from, inclusive of the value.
     # * <tt>:finish</tt> - Specifies the primary key value to end at, inclusive of the value.
     # * <tt>:error_on_ignore</tt> - Overrides the application config to specify if an error should be raised when
-    #                               the order and limit have to be ignored due to batching.
+    #   an order is present in the relation.
+    #
+    # Limits are honored, and if present there is no requirement for the batch
+    # size: it can be less than, equal to, or greater than the limit.
     #
-    # This is especially useful if you want multiple workers dealing with
-    # the same processing queue. You can make worker 1 handle all the records
-    # between id 0 and 10,000 and worker 2 handle from 10,000 and beyond
-    # (by setting the +:start+ and +:finish+ option on each worker).
+    # The options +start+ and +finish+ are especially useful if you want
+    # multiple workers dealing with the same processing queue. You can make
+    # worker 1 handle all the records between id 1 and 9999 and worker 2
+    # handle from 10000 and beyond by setting the +:start+ and +:finish+
+    # option on each worker.
     #
-    #   # Let's process the next 2000 records
-    #   Person.find_in_batches(start: 2000, batch_size: 2000) do |group|
+    #   # Let's process from record 10_000 on.
+    #   Person.find_in_batches(start: 10_000) do |group|
     #     group.each { |person| person.party_all_night! }
     #   end
     #
@@ -106,8 +121,8 @@ module ActiveRecord
     # work. This also means that this method only works when the primary key is
     # orderable (e.g. an integer or string).
     #
-    # NOTE: You can't set the limit either, that's used to control
-    # the batch sizes.
+    # NOTE: By its nature, batch processing is subject to race conditions if
+    # other processes are modifying the database.
     def find_in_batches(start: nil, finish: nil, batch_size: 1000, error_on_ignore: nil)
       relation = self
       unless block_given?
@@ -132,9 +147,9 @@ module ActiveRecord
     # If you do not provide a block to #in_batches, it will return a
     # BatchEnumerator which is enumerable.
     #
-    #   Person.in_batches.with_index do |relation, batch_index|
+    #   Person.in_batches.each_with_index do |relation, batch_index|
     #     puts "Processing relation ##{batch_index}"
-    #     relation.each { |relation| relation.delete_all }
+    #     relation.delete_all
     #   end
     #
     # Examples of calling methods on the returned BatchEnumerator object:
@@ -144,22 +159,24 @@ module ActiveRecord
     #   Person.in_batches.each_record(&:party_all_night!)
     #
     # ==== Options
-    # * <tt>:of</tt> - Specifies the size of the batch. Default to 1000.
-    # * <tt>:load</tt> - Specifies if the relation should be loaded. Default to false.
+    # * <tt>:of</tt> - Specifies the size of the batch. Defaults to 1000.
+    # * <tt>:load</tt> - Specifies if the relation should be loaded. Defaults to false.
     # * <tt>:start</tt> - Specifies the primary key value to start from, inclusive of the value.
     # * <tt>:finish</tt> - Specifies the primary key value to end at, inclusive of the value.
     # * <tt>:error_on_ignore</tt> - Overrides the application config to specify if an error should be raised when
-    #                               the order and limit have to be ignored due to batching.
+    #   an order is present in the relation.
+    #
+    # Limits are honored, and if present there is no requirement for the batch
+    # size, it can be less than, equal, or greater than the limit.
     #
-    # This is especially useful if you want to work with the
-    # ActiveRecord::Relation object instead of the array of records, or if
-    # you want multiple workers dealing with the same processing queue. You can
-    # make worker 1 handle all the records between id 0 and 10,000 and worker 2
-    # handle from 10,000 and beyond (by setting the +:start+ and +:finish+
-    # option on each worker).
+    # The options +start+ and +finish+ are especially useful if you want
+    # multiple workers dealing with the same processing queue. You can make
+    # worker 1 handle all the records between id 1 and 9999 and worker 2
+    # handle from 10000 and beyond by setting the +:start+ and +:finish+
+    # option on each worker.
     #
-    #   # Let's process the next 2000 records
-    #   Person.in_batches(of: 2000, start: 2000).update_all(awesome: true)
+    #   # Let's process from record 10_000 on.
+    #   Person.in_batches(start: 10_000).update_all(awesome: true)
     #
     # An example of calling where query method on the relation:
     #
@@ -176,34 +193,41 @@ module ActiveRecord
     #
     # NOTE: It's not possible to set the order. That is automatically set to
     # ascending on the primary key ("id ASC") to make the batch ordering
-    # consistent. Therefore the primary key must be orderable, e.g an integer
+    # consistent. Therefore the primary key must be orderable, e.g. an integer
     # or a string.
     #
-    # NOTE: You can't set the limit either, that's used to control the batch
-    # sizes.
+    # NOTE: By its nature, batch processing is subject to race conditions if
+    # other processes are modifying the database.
     def in_batches(of: 1000, start: nil, finish: nil, load: false, error_on_ignore: nil)
       relation = self
       unless block_given?
         return BatchEnumerator.new(of: of, start: start, finish: finish, relation: self)
       end
 
-      if arel.orders.present? || arel.taken.present?
-        act_on_order_or_limit_ignored(error_on_ignore)
+      if arel.orders.present?
+        act_on_ignored_order(error_on_ignore)
       end
 
-      relation = relation.reorder(batch_order).limit(of)
+      batch_limit = of
+      if limit_value
+        remaining   = limit_value
+        batch_limit = remaining if remaining < batch_limit
+      end
+
+      relation = relation.reorder(batch_order).limit(batch_limit)
       relation = apply_limits(relation, start, finish)
+      relation.skip_query_cache! # Retaining the results in the query cache would undermine the point of batching
       batch_relation = relation
 
       loop do
         if load
           records = batch_relation.records
           ids = records.map(&:id)
-          yielded_relation = self.where(primary_key => ids)
+          yielded_relation = where(primary_key => ids)
           yielded_relation.load_records(records)
         else
           ids = batch_relation.pluck(primary_key)
-          yielded_relation = self.where(primary_key => ids)
+          yielded_relation = where(primary_key => ids)
         end
 
         break if ids.empty?
@@ -213,31 +237,51 @@ module ActiveRecord
 
         yield yielded_relation
 
-        break if ids.length < of
-        batch_relation = relation.where(arel_attribute(primary_key).gt(primary_key_offset))
+        break if ids.length < batch_limit
+
+        if limit_value
+          remaining -= ids.length
+
+          if remaining == 0
+            # Saves a useless iteration when the limit is a multiple of the
+            # batch size.
+            break
+          elsif remaining < batch_limit
+            relation = relation.limit(remaining)
+          end
+        end
+
+        attr = Relation::QueryAttribute.new(primary_key, primary_key_offset, klass.type_for_attribute(primary_key))
+        batch_relation = relation.where(arel_attribute(primary_key).gt(Arel::Nodes::BindParam.new(attr)))
       end
     end
 
     private
 
-    def apply_limits(relation, start, finish)
-      relation = relation.where(arel_attribute(primary_key).gteq(start)) if start
-      relation = relation.where(arel_attribute(primary_key).lteq(finish)) if finish
-      relation
-    end
+      def apply_limits(relation, start, finish)
+        if start
+          attr = Relation::QueryAttribute.new(primary_key, start, klass.type_for_attribute(primary_key))
+          relation = relation.where(arel_attribute(primary_key).gteq(Arel::Nodes::BindParam.new(attr)))
+        end
+        if finish
+          attr = Relation::QueryAttribute.new(primary_key, finish, klass.type_for_attribute(primary_key))
+          relation = relation.where(arel_attribute(primary_key).lteq(Arel::Nodes::BindParam.new(attr)))
+        end
+        relation
+      end
 
-    def batch_order
-      "#{quoted_table_name}.#{quoted_primary_key} ASC"
-    end
+      def batch_order
+        arel_attribute(primary_key).asc
+      end
 
-    def act_on_order_or_limit_ignored(error_on_ignore)
-      raise_error = (error_on_ignore.nil? ? self.klass.error_on_ignored_order_or_limit : error_on_ignore)
+      def act_on_ignored_order(error_on_ignore)
+        raise_error = (error_on_ignore.nil? ? klass.error_on_ignored_order : error_on_ignore)
 
-      if raise_error
-        raise ArgumentError.new(ORDER_OR_LIMIT_IGNORED_MESSAGE)
-      elsif logger
-        logger.warn(ORDER_OR_LIMIT_IGNORED_MESSAGE)
+        if raise_error
+          raise ArgumentError.new(ORDER_IGNORE_MESSAGE)
+        elsif logger
+          logger.warn(ORDER_IGNORE_MESSAGE)
+        end
       end
-    end
   end
 end
diff --git a/activerecord/lib/active_record/relation/batches/batch_enumerator.rb b/activerecord/lib/active_record/relation/batches/batch_enumerator.rb
index 333b3a63cf..49697da3bf 100644
--- a/activerecord/lib/active_record/relation/batches/batch_enumerator.rb
+++ b/activerecord/lib/active_record/relation/batches/batch_enumerator.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActiveRecord
   module Batches
     class BatchEnumerator
@@ -7,7 +9,7 @@ module ActiveRecord
         @of       = of
         @relation = relation
         @start = start
-        @finish   = finish
+        @finish = finish
       end
 
       # Looping through a collection of records from the database (using the
diff --git a/activerecord/lib/active_record/relation/calculations.rb b/activerecord/lib/active_record/relation/calculations.rb
index d6d92b8607..cb0b06cfdc 100644
--- a/activerecord/lib/active_record/relation/calculations.rb
+++ b/activerecord/lib/active_record/relation/calculations.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActiveRecord
   module Calculations
     # Count the records.
@@ -38,10 +40,16 @@ module ActiveRecord
     # between databases. In invalid cases, an error from the database is thrown.
     def count(column_name = nil)
       if block_given?
-        to_a.count { |*block_args| yield(*block_args) }
-      else
-        calculate(:count, column_name)
+        unless column_name.nil?
+          ActiveSupport::Deprecation.warn \
+            "When `count' is called with a block, it ignores other arguments. " \
+            "This behavior is now deprecated and will result in an ArgumentError in Rails 6.0."
+        end
+
+        return super()
       end
+
+      calculate(:count, column_name)
     end
 
     # Calculates the average value on a given column. Returns +nil+ if there's
@@ -75,8 +83,17 @@ module ActiveRecord
     # #calculate for examples with options.
     #
     #   Person.sum(:age) # => 4562
-    def sum(column_name = nil, &block)
-      return super(&block) if block_given?
+    def sum(column_name = nil)
+      if block_given?
+        unless column_name.nil?
+          ActiveSupport::Deprecation.warn \
+            "When `sum' is called with a block, it ignores other arguments. " \
+            "This behavior is now deprecated and will result in an ArgumentError in Rails 6.0."
+        end
+
+        return super()
+      end
+
       calculate(:sum, column_name)
     end
 
@@ -112,12 +129,11 @@ module ActiveRecord
     #        ...
     #      end
     def calculate(operation, column_name)
-      if column_name.is_a?(Symbol) && attribute_alias?(column_name)
-        column_name = attribute_alias(column_name)
-      end
-
       if has_include?(column_name)
-        construct_relation_for_association_calculations.calculate(operation, column_name)
+        relation = apply_join_dependency
+        relation.distinct! if operation.to_s.downcase == "count"
+
+        relation.calculate(operation, column_name)
       else
         perform_calculation(operation, column_name)
       end
@@ -160,17 +176,19 @@ module ActiveRecord
     #
     def pluck(*column_names)
       if loaded? && (column_names.map(&:to_s) - @klass.attribute_names - @klass.attribute_aliases.keys).empty?
-        return @records.pluck(*column_names)
+        return records.pluck(*column_names)
       end
 
       if has_include?(column_names.first)
-        construct_relation_for_association_calculations.pluck(*column_names)
+        relation = apply_join_dependency
+        relation.pluck(*column_names)
       else
+        enforce_raw_sql_whitelist(column_names)
         relation = spawn
         relation.select_values = column_names.map { |cn|
           @klass.has_attribute?(cn) || @klass.attribute_alias?(cn) ? arel_attribute(cn) : cn
         }
-        result = klass.connection.select_all(relation.arel, nil, bound_attributes)
+        result = skip_query_cache_if_necessary { klass.connection.select_all(relation.arel, nil) }
         result.cast_values(klass.attribute_types)
       end
     end
@@ -185,201 +203,205 @@ module ActiveRecord
 
     private
 
-    def has_include?(column_name)
-      eager_loading? || (includes_values.present? && column_name && column_name != :all)
-    end
-
-    def perform_calculation(operation, column_name)
-      operation = operation.to_s.downcase
-
-      # If #count is used with #distinct (i.e. `relation.distinct.count`) it is
-      # considered distinct.
-      distinct = self.distinct_value
-
-      if operation == "count"
-        column_name ||= select_for_count
+      def has_include?(column_name)
+        eager_loading? || (includes_values.present? && column_name && column_name != :all)
+      end
 
-        unless arel.ast.grep(Arel::Nodes::OuterJoin).empty?
-          distinct = true
+      def perform_calculation(operation, column_name)
+        operation = operation.to_s.downcase
+
+        # If #count is used with #distinct (i.e. `relation.distinct.count`) it is
+        # considered distinct.
+        distinct = distinct_value
+
+        if operation == "count"
+          column_name ||= select_for_count
+          if column_name == :all
+            if distinct && (group_values.any? || select_values.empty? && order_values.empty?)
+              column_name = primary_key
+            end
+          elsif column_name =~ /\s*DISTINCT[\s(]+/i
+            distinct = nil
+          end
         end
 
-        column_name = primary_key if column_name == :all && distinct
-        distinct = nil if column_name =~ /\s*DISTINCT[\s(]+/i
-      end
-
-      if group_values.any?
-        execute_grouped_calculation(operation, column_name, distinct)
-      else
-        execute_simple_calculation(operation, column_name, distinct)
+        if group_values.any?
+          execute_grouped_calculation(operation, column_name, distinct)
+        else
+          execute_simple_calculation(operation, column_name, distinct)
+        end
       end
-    end
 
-    def aggregate_column(column_name)
-      return column_name if Arel::Expressions === column_name
+      def aggregate_column(column_name)
+        return column_name if Arel::Expressions === column_name
 
-      if @klass.column_names.include?(column_name.to_s)
-        Arel::Attribute.new(@klass.unscoped.table, column_name)
-      else
-        Arel.sql(column_name == :all ? "*" : column_name.to_s)
+        if @klass.has_attribute?(column_name.to_s) || @klass.attribute_alias?(column_name.to_s)
+          @klass.arel_attribute(column_name)
+        else
+          Arel.sql(column_name == :all ? "*" : column_name.to_s)
+        end
       end
-    end
-
-    def operation_over_aggregate_column(column, operation, distinct)
-      operation == 'count' ? column.count(distinct) : column.send(operation)
-    end
 
-    def execute_simple_calculation(operation, column_name, distinct) #:nodoc:
-      # PostgreSQL doesn't like ORDER BY when there are no GROUP BY
-      relation = unscope(:order)
-
-      column_alias = column_name
+      def operation_over_aggregate_column(column, operation, distinct)
+        operation == "count" ? column.count(distinct) : column.send(operation)
+      end
 
-      if operation == "count" && (relation.limit_value || relation.offset_value)
-        # Shortcut when limit is zero.
-        return 0 if relation.limit_value == 0
+      def execute_simple_calculation(operation, column_name, distinct) #:nodoc:
+        column_alias = column_name
 
-        query_builder = build_count_subquery(relation, column_name, distinct)
-      else
-        column = aggregate_column(column_name)
+        if operation == "count" && (column_name == :all && distinct || has_limit_or_offset?)
+          # Shortcut when limit is zero.
+          return 0 if limit_value == 0
 
-        select_value = operation_over_aggregate_column(column, operation, distinct)
+          query_builder = build_count_subquery(spawn, column_name, distinct)
+        else
+          # PostgreSQL doesn't like ORDER BY when there are no GROUP BY
+          relation = unscope(:order).distinct!(false)
 
-        column_alias = select_value.alias
-        column_alias ||= @klass.connection.column_name_for_operation(operation, select_value)
-        relation.select_values = [select_value]
+          column = aggregate_column(column_name)
 
-        query_builder = relation.arel
-      end
+          select_value = operation_over_aggregate_column(column, operation, distinct)
+          if operation == "sum" && distinct
+            select_value.distinct = true
+          end
 
-      result = @klass.connection.select_all(query_builder, nil, bound_attributes)
-      row    = result.first
-      value  = row && row.values.first
-      column = result.column_types.fetch(column_alias) do
-        type_for(column_name)
-      end
+          column_alias = select_value.alias
+          column_alias ||= @klass.connection.column_name_for_operation(operation, select_value)
+          relation.select_values = [select_value]
 
-      type_cast_calculated_value(value, column, operation)
-    end
+          query_builder = relation.arel
+        end
 
-    def execute_grouped_calculation(operation, column_name, distinct) #:nodoc:
-      group_attrs = group_values
+        result = skip_query_cache_if_necessary { @klass.connection.select_all(query_builder, nil) }
+        row    = result.first
+        value  = row && row.values.first
+        type   = result.column_types.fetch(column_alias) do
+          type_for(column_name)
+        end
 
-      if group_attrs.first.respond_to?(:to_sym)
-        association  = @klass._reflect_on_association(group_attrs.first)
-        associated   = group_attrs.size == 1 && association && association.belongs_to? # only count belongs_to associations
-        group_fields = Array(associated ? association.foreign_key : group_attrs)
-      else
-        group_fields = group_attrs
+        type_cast_calculated_value(value, type, operation)
       end
-      group_fields = arel_columns(group_fields)
 
-      group_aliases = group_fields.map { |field| column_alias_for(field) }
-      group_columns = group_aliases.zip(group_fields)
-
-      if operation == 'count' && column_name == :all
-        aggregate_alias = 'count_all'
-      else
-        aggregate_alias = column_alias_for([operation, column_name].join(' '))
-      end
+      def execute_grouped_calculation(operation, column_name, distinct) #:nodoc:
+        group_attrs = group_values
 
-      select_values = [
-        operation_over_aggregate_column(
-          aggregate_column(column_name),
-          operation,
-          distinct).as(aggregate_alias)
-      ]
-      select_values += select_values unless having_clause.empty?
-
-      select_values.concat group_columns.map { |aliaz, field|
-        if field.respond_to?(:as)
-          field.as(aliaz)
+        if group_attrs.first.respond_to?(:to_sym)
+          association  = @klass._reflect_on_association(group_attrs.first)
+          associated   = group_attrs.size == 1 && association && association.belongs_to? # only count belongs_to associations
+          group_fields = Array(associated ? association.foreign_key : group_attrs)
         else
-          "#{field} AS #{aliaz}"
+          group_fields = group_attrs
         end
-      }
-
-      relation = except(:group)
-      relation.group_values  = group_fields
-      relation.select_values = select_values
+        group_fields = arel_columns(group_fields)
 
-      calculated_data = @klass.connection.select_all(relation, nil, relation.bound_attributes)
+        group_aliases = group_fields.map { |field| column_alias_for(field) }
+        group_columns = group_aliases.zip(group_fields)
 
-      if association
-        key_ids     = calculated_data.collect { |row| row[group_aliases.first] }
-        key_records = association.klass.base_class.where(association.klass.base_class.primary_key => key_ids)
-        key_records = Hash[key_records.map { |r| [r.id, r] }]
-      end
+        if operation == "count" && column_name == :all
+          aggregate_alias = "count_all"
+        else
+          aggregate_alias = column_alias_for([operation, column_name].join(" "))
+        end
 
-      Hash[calculated_data.map do |row|
-        key = group_columns.map { |aliaz, col_name|
-          column = calculated_data.column_types.fetch(aliaz) do
-            type_for(col_name)
+        select_values = [
+          operation_over_aggregate_column(
+            aggregate_column(column_name),
+            operation,
+            distinct).as(aggregate_alias)
+        ]
+        select_values += self.select_values unless having_clause.empty?
+
+        select_values.concat group_columns.map { |aliaz, field|
+          if field.respond_to?(:as)
+            field.as(aliaz)
+          else
+            "#{field} AS #{aliaz}"
           end
-          type_cast_calculated_value(row[aliaz], column)
         }
-        key = key.first if key.size == 1
-        key = key_records[key] if associated
 
-        column_type = calculated_data.column_types.fetch(aggregate_alias) { type_for(column_name) }
-        [key, type_cast_calculated_value(row[aggregate_alias], column_type, operation)]
-      end]
-    end
+        relation = except(:group).distinct!(false)
+        relation.group_values  = group_fields
+        relation.select_values = select_values
 
-    # Converts the given keys to the value that the database adapter returns as
-    # a usable column name:
-    #
-    #   column_alias_for("users.id")                 # => "users_id"
-    #   column_alias_for("sum(id)")                  # => "sum_id"
-    #   column_alias_for("count(distinct users.id)") # => "count_distinct_users_id"
-    #   column_alias_for("count(*)")                 # => "count_all"
-    def column_alias_for(keys)
-      if keys.respond_to? :name
-        keys = "#{keys.relation.name}.#{keys.name}"
+        calculated_data = skip_query_cache_if_necessary { @klass.connection.select_all(relation.arel, nil) }
+
+        if association
+          key_ids     = calculated_data.collect { |row| row[group_aliases.first] }
+          key_records = association.klass.base_class.where(association.klass.base_class.primary_key => key_ids)
+          key_records = Hash[key_records.map { |r| [r.id, r] }]
+        end
+
+        Hash[calculated_data.map do |row|
+          key = group_columns.map { |aliaz, col_name|
+            type = type_for(col_name) do
+              calculated_data.column_types.fetch(aliaz, Type.default_value)
+            end
+            type_cast_calculated_value(row[aliaz], type)
+          }
+          key = key.first if key.size == 1
+          key = key_records[key] if associated
+
+          type = calculated_data.column_types.fetch(aggregate_alias) { type_for(column_name) }
+          [key, type_cast_calculated_value(row[aggregate_alias], type, operation)]
+        end]
       end
 
-      table_name = keys.to_s.downcase
-      table_name.gsub!(/\*/, 'all')
-      table_name.gsub!(/\W+/, ' ')
-      table_name.strip!
-      table_name.gsub!(/ +/, '_')
+      # Converts the given keys to the value that the database adapter returns as
+      # a usable column name:
+      #
+      #   column_alias_for("users.id")                 # => "users_id"
+      #   column_alias_for("sum(id)")                  # => "sum_id"
+      #   column_alias_for("count(distinct users.id)") # => "count_distinct_users_id"
+      #   column_alias_for("count(*)")                 # => "count_all"
+      def column_alias_for(keys)
+        if keys.respond_to? :name
+          keys = "#{keys.relation.name}.#{keys.name}"
+        end
 
-      @klass.connection.table_alias_for(table_name)
-    end
+        table_name = keys.to_s.downcase
+        table_name.gsub!(/\*/, "all")
+        table_name.gsub!(/\W+/, " ")
+        table_name.strip!
+        table_name.gsub!(/ +/, "_")
 
-    def type_for(field)
-      field_name = field.respond_to?(:name) ? field.name.to_s : field.to_s.split('.').last
-      @klass.type_for_attribute(field_name)
-    end
+        @klass.connection.table_alias_for(table_name)
+      end
 
-    def type_cast_calculated_value(value, type, operation = nil)
-      case operation
-        when 'count'   then value.to_i
-        when 'sum'     then type.deserialize(value || 0)
-        when 'average' then value.respond_to?(:to_d) ? value.to_d : value
+      def type_for(field, &block)
+        field_name = field.respond_to?(:name) ? field.name.to_s : field.to_s.split(".").last
+        @klass.type_for_attribute(field_name, &block)
+      end
+
+      def type_cast_calculated_value(value, type, operation = nil)
+        case operation
+        when "count"   then value.to_i
+        when "sum"     then type.deserialize(value || 0)
+        when "average" then value.respond_to?(:to_d) ? value.to_d : value
         else type.deserialize(value)
+        end
       end
-    end
 
-    def select_for_count
-      if select_values.present?
-        return select_values.first if select_values.one?
-        select_values.join(", ")
-      else
-        :all
+      def select_for_count
+        if select_values.present?
+          return select_values.first if select_values.one?
+          select_values.join(", ")
+        else
+          :all
+        end
       end
-    end
 
-    def build_count_subquery(relation, column_name, distinct)
-      column_alias = Arel.sql('count_column')
-      subquery_alias = Arel.sql('subquery_for_count')
+      def build_count_subquery(relation, column_name, distinct)
+        if column_name == :all
+          relation.select_values = [ Arel.sql(FinderMethods::ONE_AS_ONE) ] unless distinct
+        else
+          column_alias = Arel.sql("count_column")
+          relation.select_values = [ aggregate_column(column_name).as(column_alias) ]
+        end
 
-      aliased_column = aggregate_column(column_name == :all ? 1 : column_name).as(column_alias)
-      relation.select_values = [aliased_column]
-      subquery = relation.arel.as(subquery_alias)
+        subquery = relation.arel.as(Arel.sql("subquery_for_count"))
+        select_value = operation_over_aggregate_column(column_alias || Arel.star, "count", false)
 
-      sm = Arel::SelectManager.new relation.engine
-      select_value = operation_over_aggregate_column(column_alias, 'count', distinct)
-      sm.project(select_value).from(subquery)
-    end
+        Arel::SelectManager.new(subquery).project(select_value)
+      end
   end
 end
diff --git a/activerecord/lib/active_record/relation/delegation.rb b/activerecord/lib/active_record/relation/delegation.rb
index 2484cb3264..4863befec8 100644
--- a/activerecord/lib/active_record/relation/delegation.rb
+++ b/activerecord/lib/active_record/relation/delegation.rb
@@ -1,4 +1,4 @@
-require 'active_support/concern'
+# frozen_string_literal: true
 
 module ActiveRecord
   module Delegation # :nodoc:
@@ -17,7 +17,10 @@ module ActiveRecord
           delegate = Class.new(klass) {
             include ClassSpecificRelation
           }
-          const_set klass.name.gsub('::'.freeze, '_'.freeze), delegate
+          mangled_name = klass.name.gsub("::".freeze, "_".freeze)
+          const_set mangled_name, delegate
+          private_constant mangled_name
+
           cache[klass] = delegate
         end
       end
@@ -35,12 +38,12 @@ module ActiveRecord
     # may vary depending on the klass of a relation, so we create a subclass of Relation
     # for each different klass, and the delegations are compiled into that subclass only.
 
-    delegate :to_xml, :encode_with, :length, :collect, :map, :each, :all?, :include?, :to_ary, :join,
-             :[], :&, :|, :+, :-, :sample, :reverse, :compact, :in_groups, :in_groups_of,
-             :shuffle, :split, to: :records
+    delegate :to_xml, :encode_with, :length, :each, :uniq, :join,
+             :[], :&, :|, :+, :-, :sample, :reverse, :rotate, :compact, :in_groups, :in_groups_of,
+             :to_sentence, :to_formatted_s, :as_json,
+             :shuffle, :split, :slice, :index, :rindex, to: :records
 
-    delegate :table_name, :quoted_table_name, :primary_key, :quoted_primary_key,
-             :connection, :columns_hash, :to => :klass
+    delegate :primary_key, :connection, to: :klass
 
     module ClassSpecificRelation # :nodoc:
       extend ActiveSupport::Concern
@@ -58,7 +61,7 @@ module ActiveRecord
           @delegation_mutex.synchronize do
             return if method_defined?(method)
 
-            if method.to_s =~ /\A[a-zA-Z_]\w*[!?]?\z/
+            if /\A[a-zA-Z_]\w*[!?]?\z/.match?(method)
               module_eval <<-RUBY, __FILE__, __LINE__ + 1
                 def #{method}(*args, &block)
                   scoping { @klass.#{method}(*args, &block) }
@@ -71,28 +74,22 @@ module ActiveRecord
             end
           end
         end
+      end
 
-        def delegate(method, opts = {})
-          @delegation_mutex.synchronize do
-            return if method_defined?(method)
+      private
+
+        def method_missing(method, *args, &block)
+          if @klass.respond_to?(method)
+            self.class.delegate_to_scoped_klass(method)
+            scoping { @klass.public_send(method, *args, &block) }
+          elsif arel.respond_to?(method)
+            ActiveSupport::Deprecation.warn \
+              "Delegating #{method} to arel is deprecated and will be removed in Rails 6.0."
+            arel.public_send(method, *args, &block)
+          else
             super
           end
         end
-      end
-
-      protected
-
-      def method_missing(method, *args, &block)
-        if @klass.respond_to?(method)
-          self.class.delegate_to_scoped_klass(method)
-          scoping { @klass.public_send(method, *args, &block) }
-        elsif arel.respond_to?(method)
-          self.class.delegate method, :to => :arel
-          arel.public_send(method, *args, &block)
-        else
-          super
-        end
-      end
     end
 
     module ClassMethods # :nodoc:
@@ -102,26 +99,14 @@ module ActiveRecord
 
       private
 
-      def relation_class_for(klass)
-        klass.relation_delegate_class(self)
-      end
-    end
-
-    def respond_to?(method, include_private = false)
-      super || @klass.respond_to?(method, include_private) ||
-        arel.respond_to?(method, include_private)
+        def relation_class_for(klass)
+          klass.relation_delegate_class(self)
+        end
     end
 
-    protected
-
-    def method_missing(method, *args, &block)
-      if @klass.respond_to?(method)
-        scoping { @klass.public_send(method, *args, &block) }
-      elsif arel.respond_to?(method)
-        arel.public_send(method, *args, &block)
-      else
-        super
+    private
+      def respond_to_missing?(method, _)
+        super || @klass.respond_to?(method) || arel.respond_to?(method)
       end
-    end
   end
 end
diff --git a/activerecord/lib/active_record/relation/finder_methods.rb b/activerecord/lib/active_record/relation/finder_methods.rb
index d255cad91b..ff06ecbee1 100644
--- a/activerecord/lib/active_record/relation/finder_methods.rb
+++ b/activerecord/lib/active_record/relation/finder_methods.rb
@@ -1,8 +1,10 @@
-require 'active_support/core_ext/string/filters'
+# frozen_string_literal: true
+
+require "active_support/core_ext/string/filters"
 
 module ActiveRecord
   module FinderMethods
-    ONE_AS_ONE = '1 AS one'
+    ONE_AS_ONE = "1 AS one"
 
     # Find by id - This can either be a specific id (1), a list of ids (1, 5, 6), or an array of ids ([5, 6, 10]).
     # If one or more records can not be found for the requested ids, then RecordNotFound will be raised. If the primary key
@@ -16,9 +18,10 @@ module ActiveRecord
     #   Person.find([1])        # returns an array for the object with ID = 1
     #   Person.where("administrator = 1").order("created_on DESC").find(1)
     #
-    # NOTE: The returned records may not be in the same order as the ids you
-    # provide since database rows are unordered. You'd need to provide an explicit QueryMethods#order
-    # option if you want the results are sorted.
+    # NOTE: The returned records are in the same order as the ids you provide.
+    # If you want the results to be sorted by database, you can use ActiveRecord::QueryMethods#where
+    # method and provide an explicit ActiveRecord::QueryMethods#order option.
+    # But ActiveRecord::QueryMethods#where method doesn't raise ActiveRecord::RecordNotFound.
     #
     # ==== Find with lock
     #
@@ -76,7 +79,7 @@ module ActiveRecord
     #   Post.find_by "published_at < ?", 2.weeks.ago
     def find_by(arg, *args)
       where(arg, *args).take
-    rescue RangeError
+    rescue ::RangeError
       nil
     end
 
@@ -84,9 +87,9 @@ module ActiveRecord
     # an ActiveRecord::RecordNotFound error.
     def find_by!(arg, *args)
       where(arg, *args).take!
-    rescue RangeError
+    rescue ::RangeError
       raise RecordNotFound.new("Couldn't find #{@klass.name} with an out of range value",
-                               @klass.name)
+                               @klass.name, @klass.primary_key)
     end
 
     # Gives a record (or N records if a parameter is supplied) without any implied
@@ -97,13 +100,13 @@ module ActiveRecord
     #   Person.take(5) # returns 5 objects fetched by SELECT * FROM people LIMIT 5
     #   Person.where(["name LIKE '%?'", name]).take
     def take(limit = nil)
-      limit ? limit(limit).to_a : find_take
+      limit ? find_take_with_limit(limit) : find_take
     end
 
     # Same as #take but raises ActiveRecord::RecordNotFound if no record
     # is found. Note that #take! accepts no arguments.
     def take!
-      take or raise RecordNotFound.new("Couldn't find #{@klass.name} with [#{arel.where_sql(@klass.arel_engine)}]")
+      take || raise_record_not_found_exception!
     end
 
     # Find the first record (or first N records if a parameter is supplied).
@@ -117,7 +120,7 @@ module ActiveRecord
     #
     def first(limit = nil)
       if limit
-        find_nth_with_limit_and_offset(0, limit, offset: offset_index)
+        find_nth_with_limit(0, limit)
       else
         find_nth 0
       end
@@ -126,7 +129,7 @@ module ActiveRecord
     # Same as #first but raises ActiveRecord::RecordNotFound if no record
     # is found. Note that #first! accepts no arguments.
     def first!
-      find_nth! 0
+      first || raise_record_not_found_exception!
     end
 
     # Find the last record (or last N records if a parameter is supplied).
@@ -147,25 +150,16 @@ module ActiveRecord
     def last(limit = nil)
       return find_last(limit) if loaded? || limit_value
 
-      result = limit(limit || 1)
-      result.order!(arel_attribute(primary_key)) if order_values.empty? && primary_key
+      result = ordered_relation.limit(limit)
       result = result.reverse_order!
 
       limit ? result.reverse : result.first
-    rescue ActiveRecord::IrreversibleOrderError
-      ActiveSupport::Deprecation.warn(<<-WARNING.squish)
-          Finding a last element by loading the relation when SQL ORDER
-          can not be reversed is deprecated.
-          Rails 5.1 will raise ActiveRecord::IrreversibleOrderError in this case.
-          Please call `to_a.last` if you still want to load the relation.
-      WARNING
-      find_last(limit)
     end
 
     # Same as #last but raises ActiveRecord::RecordNotFound if no record
     # is found. Note that #last! accepts no arguments.
     def last!
-      last or raise RecordNotFound.new("Couldn't find #{@klass.name} with [#{arel.where_sql(@klass.arel_engine)}]")
+      last || raise_record_not_found_exception!
     end
 
     # Find the second record.
@@ -181,7 +175,7 @@ module ActiveRecord
     # Same as #second but raises ActiveRecord::RecordNotFound if no record
     # is found.
     def second!
-      find_nth! 1
+      second || raise_record_not_found_exception!
     end
 
     # Find the third record.
@@ -197,7 +191,7 @@ module ActiveRecord
     # Same as #third but raises ActiveRecord::RecordNotFound if no record
     # is found.
     def third!
-      find_nth! 2
+      third || raise_record_not_found_exception!
     end
 
     # Find the fourth record.
@@ -213,7 +207,7 @@ module ActiveRecord
     # Same as #fourth but raises ActiveRecord::RecordNotFound if no record
     # is found.
     def fourth!
-      find_nth! 3
+      fourth || raise_record_not_found_exception!
     end
 
     # Find the fifth record.
@@ -229,7 +223,7 @@ module ActiveRecord
     # Same as #fifth but raises ActiveRecord::RecordNotFound if no record
     # is found.
     def fifth!
-      find_nth! 4
+      fifth || raise_record_not_found_exception!
     end
 
     # Find the forty-second record. Also known as accessing "the reddit".
@@ -245,7 +239,7 @@ module ActiveRecord
     # Same as #forty_two but raises ActiveRecord::RecordNotFound if no record
     # is found.
     def forty_two!
-      find_nth! 41
+      forty_two || raise_record_not_found_exception!
     end
 
     # Find the third-to-last record.
@@ -261,7 +255,7 @@ module ActiveRecord
     # Same as #third_to_last but raises ActiveRecord::RecordNotFound if no record
     # is found.
     def third_to_last!
-      find_nth_from_last 3 or raise RecordNotFound.new("Couldn't find #{@klass.name} with [#{arel.where_sql(@klass.arel_engine)}]")
+      third_to_last || raise_record_not_found_exception!
     end
 
     # Find the second-to-last record.
@@ -277,7 +271,7 @@ module ActiveRecord
     # Same as #second_to_last but raises ActiveRecord::RecordNotFound if no record
     # is found.
     def second_to_last!
-      find_nth_from_last 2 or raise RecordNotFound.new("Couldn't find #{@klass.name} with [#{arel.where_sql(@klass.arel_engine)}]")
+      second_to_last || raise_record_not_found_exception!
     end
 
     # Returns true if a record exists in the table that matches the +id+ or
@@ -291,7 +285,7 @@ module ActiveRecord
     # * Hash - Finds the record that matches these +find+-style conditions
     #   (such as <tt>{name: 'David'}</tt>).
     # * +false+ - Returns always +false+.
-    # * No args - Returns +false+ if the table is empty, +true+ otherwise.
+    # * No args - Returns +false+ if the relation is empty, +true+ otherwise.
     #
     # For more information about specifying conditions as a hash or array,
     # see the Conditions section in the introduction to ActiveRecord::Base.
@@ -307,33 +301,26 @@ module ActiveRecord
     #   Person.exists?(name: 'David')
     #   Person.exists?(false)
     #   Person.exists?
+    #   Person.where(name: 'Spartacus', rating: 4).exists?
     def exists?(conditions = :none)
       if Base === conditions
-        conditions = conditions.id
-        ActiveSupport::Deprecation.warn(<<-MSG.squish)
+        raise ArgumentError, <<-MSG.squish
           You are passing an instance of ActiveRecord::Base to `exists?`.
           Please pass the id of the object by calling `.id`.
         MSG
       end
 
-      return false if !conditions
-
-      relation = apply_join_dependency(self, construct_join_dependency(eager_loading: false))
-      return false if ActiveRecord::NullRelation === relation
-
-      relation = relation.except(:select, :order).select(ONE_AS_ONE).limit(1)
+      return false if !conditions || limit_value == 0
 
-      case conditions
-      when Array, Hash
-        relation = relation.where(conditions)
-      else
-        unless conditions == :none
-          relation = relation.where(primary_key => conditions)
-        end
+      if eager_loading?
+        relation = apply_join_dependency(construct_join_dependency(eager_loading: false))
+        return relation.exists?(conditions)
       end
 
-      connection.select_value(relation, "#{name} Exists", relation.bound_attributes) ? true : false
-    rescue RangeError
+      relation = construct_relation_for_exists(conditions)
+
+      skip_query_cache_if_necessary { connection.select_value(relation.arel, "#{name} Exists") } ? true : false
+    rescue ::RangeError
       false
     end
 
@@ -345,248 +332,240 @@ module ActiveRecord
     # of results obtained should be provided in the +result_size+ argument and
     # the expected number of results should be provided in the +expected_size+
     # argument.
-    def raise_record_not_found_exception!(ids, result_size, expected_size) #:nodoc:
-      conditions = arel.where_sql(@klass.arel_engine)
+    def raise_record_not_found_exception!(ids = nil, result_size = nil, expected_size = nil, key = primary_key, not_found_ids = nil) # :nodoc:
+      conditions = arel.where_sql(@klass)
       conditions = " [#{conditions}]" if conditions
-
-      if Array(ids).size == 1
-        error = "Couldn't find #{@klass.name} with '#{primary_key}'=#{ids}#{conditions}"
+      name = @klass.name
+
+      if ids.nil?
+        error = "Couldn't find #{name}".dup
+        error << " with#{conditions}" if conditions
+        raise RecordNotFound.new(error, name, key)
+      elsif Array(ids).size == 1
+        error = "Couldn't find #{name} with '#{key}'=#{ids}#{conditions}"
+        raise RecordNotFound.new(error, name, key, ids)
       else
-        error = "Couldn't find all #{@klass.name.pluralize} with '#{primary_key}': "
-        error << "(#{ids.join(", ")})#{conditions} (found #{result_size} results, but was looking for #{expected_size})"
+        error = "Couldn't find all #{name.pluralize} with '#{key}': ".dup
+        error << "(#{ids.join(", ")})#{conditions} (found #{result_size} results, but was looking for #{expected_size})."
+        error << " Couldn't find #{name.pluralize(not_found_ids.size)} with #{key.to_s.pluralize(not_found_ids.size)} #{not_found_ids.join(', ')}." if not_found_ids
+        raise RecordNotFound.new(error, name, key, ids)
       end
-
-      raise RecordNotFound, error
     end
 
     private
 
-    def offset_index
-      offset_value || 0
-    end
+      def offset_index
+        offset_value || 0
+      end
 
-    def find_with_associations
-      # NOTE: the JoinDependency constructed here needs to know about
-      #       any joins already present in `self`, so pass them in
-      #
-      # failing to do so means that in cases like activerecord/test/cases/associations/inner_join_association_test.rb:136
-      # incorrect SQL is generated. In that case, the join dependency for
-      # SpecialCategorizations is constructed without knowledge of the
-      # preexisting join in joins_values to categorizations (by way of
-      # the `has_many :through` for categories).
-      #
-      join_dependency = construct_join_dependency(joins_values)
-
-      aliases  = join_dependency.aliases
-      relation = select aliases.columns
-      relation = apply_join_dependency(relation, join_dependency)
-
-      if block_given?
-        yield relation
-      else
-        if ActiveRecord::NullRelation === relation
-          []
+      def find_with_associations
+        # NOTE: the JoinDependency constructed here needs to know about
+        #       any joins already present in `self`, so pass them in
+        #
+        # failing to do so means that in cases like activerecord/test/cases/associations/inner_join_association_test.rb:136
+        # incorrect SQL is generated. In that case, the join dependency for
+        # SpecialCategorizations is constructed without knowledge of the
+        # preexisting join in joins_values to categorizations (by way of
+        # the `has_many :through` for categories).
+        #
+        join_dependency = construct_join_dependency
+
+        relation = apply_join_dependency(join_dependency)
+        relation._select!(join_dependency.aliases.columns)
+
+        yield relation, join_dependency
+      end
+
+      def construct_relation_for_exists(conditions)
+        relation = except(:select, :distinct, :order)._select!(ONE_AS_ONE).limit!(1)
+
+        case conditions
+        when Array, Hash
+          relation.where!(conditions)
         else
-          arel = relation.arel
-          rows = connection.select_all(arel, 'SQL', relation.bound_attributes)
-          join_dependency.instantiate(rows, aliases)
+          relation.where!(primary_key => conditions) unless conditions == :none
         end
-      end
-    end
 
-    def construct_join_dependency(joins = [], eager_loading: true)
-      including = eager_load_values + includes_values
-      ActiveRecord::Associations::JoinDependency.new(@klass, including, joins, eager_loading: eager_loading)
-    end
+        relation
+      end
 
-    def construct_relation_for_association_calculations
-      apply_join_dependency(self, construct_join_dependency(joins_values))
-    end
+      def construct_join_dependency(eager_loading: true)
+        including = eager_load_values + includes_values
+        ActiveRecord::Associations::JoinDependency.new(
+          klass, table, including, alias_tracker(joins_values), eager_loading: eager_loading
+        )
+      end
 
-    def apply_join_dependency(relation, join_dependency)
-      relation = relation.except(:includes, :eager_load, :preload)
-      relation = relation.joins join_dependency
+      def apply_join_dependency(join_dependency = construct_join_dependency)
+        relation = except(:includes, :eager_load, :preload).joins!(join_dependency)
 
-      if using_limitable_reflections?(join_dependency.reflections)
-        relation
-      else
-        if relation.limit_value
-          limited_ids = limited_ids_for(relation)
-          limited_ids.empty? ? relation.none! : relation.where!(primary_key => limited_ids)
+        if using_limitable_reflections?(join_dependency.reflections)
+          relation
+        else
+          if relation.limit_value
+            limited_ids = limited_ids_for(relation)
+            limited_ids.empty? ? relation.none! : relation.where!(primary_key => limited_ids)
+          end
+          relation.except(:limit, :offset)
         end
-        relation.except(:limit, :offset)
       end
-    end
 
-    def limited_ids_for(relation)
-      values = @klass.connection.columns_for_distinct(
-        "#{quoted_table_name}.#{quoted_primary_key}", relation.order_values)
+      def limited_ids_for(relation)
+        values = @klass.connection.columns_for_distinct(
+          connection.column_name_from_arel_node(arel_attribute(primary_key)),
+          relation.order_values
+        )
 
-      relation = relation.except(:select).select(values).distinct!
-      arel = relation.arel
+        relation = relation.except(:select).select(values).distinct!
 
-      id_rows = @klass.connection.select_all(arel, 'SQL', relation.bound_attributes)
-      id_rows.map {|row| row[primary_key]}
-    end
+        id_rows = skip_query_cache_if_necessary { @klass.connection.select_all(relation.arel, "SQL") }
+        id_rows.map { |row| row[primary_key] }
+      end
 
-    def using_limitable_reflections?(reflections)
-      reflections.none?(&:collection?)
-    end
+      def using_limitable_reflections?(reflections)
+        reflections.none?(&:collection?)
+      end
 
-    protected
+      def find_with_ids(*ids)
+        raise UnknownPrimaryKey.new(@klass) if primary_key.nil?
 
-    def find_with_ids(*ids)
-      raise UnknownPrimaryKey.new(@klass) if primary_key.nil?
+        expects_array = ids.first.kind_of?(Array)
+        return ids.first if expects_array && ids.first.empty?
 
-      expects_array = ids.first.kind_of?(Array)
-      return ids.first if expects_array && ids.first.empty?
+        ids = ids.flatten.compact.uniq
 
-      ids = ids.flatten.compact.uniq
+        model_name = @klass.name
 
-      case ids.size
-      when 0
-        raise RecordNotFound, "Couldn't find #{@klass.name} without an ID"
-      when 1
-        result = find_one(ids.first)
-        expects_array ? [ result ] : result
-      else
-        find_some(ids)
+        case ids.size
+        when 0
+          error_message = "Couldn't find #{model_name} without an ID"
+          raise RecordNotFound.new(error_message, model_name, primary_key)
+        when 1
+          result = find_one(ids.first)
+          expects_array ? [ result ] : result
+        else
+          find_some(ids)
+        end
+      rescue ::RangeError
+        error_message = "Couldn't find #{model_name} with an out of range ID"
+        raise RecordNotFound.new(error_message, model_name, primary_key, ids)
       end
-    rescue RangeError
-      raise RecordNotFound, "Couldn't find #{@klass.name} with an out of range ID"
-    end
 
-    def find_one(id)
-      if ActiveRecord::Base === id
-        id = id.id
-        ActiveSupport::Deprecation.warn(<<-MSG.squish)
-          You are passing an instance of ActiveRecord::Base to `find`.
-          Please pass the id of the object by calling `.id`.
-        MSG
-      end
+      def find_one(id)
+        if ActiveRecord::Base === id
+          raise ArgumentError, <<-MSG.squish
+            You are passing an instance of ActiveRecord::Base to `find`.
+            Please pass the id of the object by calling `.id`.
+          MSG
+        end
 
-      relation = where(primary_key => id)
-      record = relation.take
+        relation = where(primary_key => id)
+        record = relation.take
 
-      raise_record_not_found_exception!(id, 0, 1) unless record
+        raise_record_not_found_exception!(id, 0, 1) unless record
 
-      record
-    end
+        record
+      end
 
-    def find_some(ids)
-      return find_some_ordered(ids) unless order_values.present?
+      def find_some(ids)
+        return find_some_ordered(ids) unless order_values.present?
 
-      result = where(primary_key => ids).to_a
+        result = where(primary_key => ids).to_a
 
-      expected_size =
-        if limit_value && ids.size > limit_value
-          limit_value
-        else
-          ids.size
-        end
+        expected_size =
+          if limit_value && ids.size > limit_value
+            limit_value
+          else
+            ids.size
+          end
 
-      # 11 ids with limit 3, offset 9 should give 2 results.
-      if offset_value && (ids.size - offset_value < expected_size)
-        expected_size = ids.size - offset_value
-      end
+        # 11 ids with limit 3, offset 9 should give 2 results.
+        if offset_value && (ids.size - offset_value < expected_size)
+          expected_size = ids.size - offset_value
+        end
 
-      if result.size == expected_size
-        result
-      else
-        raise_record_not_found_exception!(ids, result.size, expected_size)
+        if result.size == expected_size
+          result
+        else
+          raise_record_not_found_exception!(ids, result.size, expected_size)
+        end
       end
-    end
 
-    def find_some_ordered(ids)
-      ids = ids.slice(offset_value || 0, limit_value || ids.size) || []
+      def find_some_ordered(ids)
+        ids = ids.slice(offset_value || 0, limit_value || ids.size) || []
 
-      result = except(:limit, :offset).where(primary_key => ids).records
+        result = except(:limit, :offset).where(primary_key => ids).records
 
-      if result.size == ids.size
-        pk_type = @klass.type_for_attribute(primary_key)
+        if result.size == ids.size
+          pk_type = @klass.type_for_attribute(primary_key)
 
-        records_by_id = result.index_by(&:id)
-        ids.map { |id| records_by_id.fetch(pk_type.cast(id)) }
-      else
-        raise_record_not_found_exception!(ids, result.size, ids.size)
+          records_by_id = result.index_by(&:id)
+          ids.map { |id| records_by_id.fetch(pk_type.cast(id)) }
+        else
+          raise_record_not_found_exception!(ids, result.size, ids.size)
+        end
       end
-    end
 
-    def find_take
-      if loaded?
-        @records.first
-      else
-        @take ||= limit(1).records.first
+      def find_take
+        if loaded?
+          records.first
+        else
+          @take ||= limit(1).records.first
+        end
       end
-    end
 
-    def find_nth(index, offset = nil)
-      # TODO: once the offset argument is removed we rely on offset_index
-      # within find_nth_with_limit, rather than pass it in via
-      # find_nth_with_limit_and_offset
-      if offset
-        ActiveSupport::Deprecation.warn(<<-MSG.squish)
-          Passing an offset argument to find_nth is deprecated,
-          please use Relation#offset instead.
-        MSG
-      end
-      if loaded?
-        @records[index]
-      else
-        offset ||= offset_index
-        @offsets[offset + index] ||= find_nth_with_limit_and_offset(index, 1, offset: offset).first
+      def find_take_with_limit(limit)
+        if loaded?
+          records.take(limit)
+        else
+          limit(limit).to_a
+        end
       end
-    end
-
-    def find_nth!(index)
-      find_nth(index) or raise RecordNotFound.new("Couldn't find #{@klass.name} with [#{arel.where_sql(@klass.arel_engine)}]")
-    end
 
-    def find_nth_with_limit(index, limit)
-      # TODO: once the offset argument is removed from find_nth,
-      # find_nth_with_limit_and_offset can be merged into this method
-      relation = if order_values.empty? && primary_key
-                   order(arel_attribute(primary_key).asc)
-                 else
-                   self
-                 end
-
-      relation = relation.offset(index) unless index.zero?
-      relation.limit(limit).to_a
-    end
+      def find_nth(index)
+        @offsets[offset_index + index] ||= find_nth_with_limit(index, 1).first
+      end
 
-    def find_nth_from_last(index)
-      if loaded?
-        @records[-index]
-      else
-        relation = if order_values.empty? && primary_key
-                     order(arel_attribute(primary_key).asc)
-                   else
-                     self
-                   end
-
-        relation.to_a[-index]
-        # TODO: can be made more performant on large result sets by
-        # for instance, last(index)[-index] (which would require
-        # refactoring the last(n) finder method to make test suite pass),
-        # or by using a combination of reverse_order, limit, and offset,
-        # e.g., reverse_order.offset(index-1).first
+      def find_nth_with_limit(index, limit)
+        if loaded?
+          records[index, limit] || []
+        else
+          relation = ordered_relation
+
+          if limit_value.nil? || index < limit_value
+            relation = relation.offset(offset_index + index) unless index.zero?
+            relation.limit(limit).to_a
+          else
+            []
+          end
+        end
       end
-    end
 
-    private
+      def find_nth_from_last(index)
+        if loaded?
+          records[-index]
+        else
+          relation = ordered_relation
+
+          relation.to_a[-index]
+          # TODO: can be made more performant on large result sets by
+          # for instance, last(index)[-index] (which would require
+          # refactoring the last(n) finder method to make test suite pass),
+          # or by using a combination of reverse_order, limit, and offset,
+          # e.g., reverse_order.offset(index-1).first
+        end
+      end
 
-    def find_nth_with_limit_and_offset(index, limit, offset:) # :nodoc:
-      if loaded?
-        @records[index, limit]
-      else
-        index += offset
-        find_nth_with_limit(index, limit)
+      def find_last(limit)
+        limit ? records.last(limit) : records.last
       end
-    end
 
-    def find_last(limit)
-      limit ? records.last(limit) : records.last
-    end
+      def ordered_relation
+        if order_values.empty? && primary_key
+          order(arel_attribute(primary_key).asc)
+        else
+          self
+        end
+      end
   end
 end
diff --git a/activerecord/lib/active_record/relation/from_clause.rb b/activerecord/lib/active_record/relation/from_clause.rb
index 8945cb0cc5..c53a682aee 100644
--- a/activerecord/lib/active_record/relation/from_clause.rb
+++ b/activerecord/lib/active_record/relation/from_clause.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActiveRecord
   class Relation
     class FromClause # :nodoc:
@@ -8,14 +10,6 @@ module ActiveRecord
         @name = name
       end
 
-      def binds
-        if value.is_a?(Relation)
-          value.bound_attributes
-        else
-          []
-        end
-      end
-
       def merge(other)
         self
       end
diff --git a/activerecord/lib/active_record/relation/merger.rb b/activerecord/lib/active_record/relation/merger.rb
index 396638d74d..b736b21525 100644
--- a/activerecord/lib/active_record/relation/merger.rb
+++ b/activerecord/lib/active_record/relation/merger.rb
@@ -1,4 +1,6 @@
-require 'active_support/core_ext/hash/keys'
+# frozen_string_literal: true
+
+require "active_support/core_ext/hash/keys"
 
 module ActiveRecord
   class Relation
@@ -83,85 +85,82 @@ module ActiveRecord
 
       private
 
-      def merge_preloads
-        return if other.preload_values.empty? && other.includes_values.empty?
+        def merge_preloads
+          return if other.preload_values.empty? && other.includes_values.empty?
 
-        if other.klass == relation.klass
-          relation.preload!(*other.preload_values) unless other.preload_values.empty?
-          relation.includes!(other.includes_values) unless other.includes_values.empty?
-        else
-          reflection = relation.klass.reflect_on_all_associations.find do |r|
-            r.class_name == other.klass.name
-          end || return
+          if other.klass == relation.klass
+            relation.preload!(*other.preload_values) unless other.preload_values.empty?
+            relation.includes!(other.includes_values) unless other.includes_values.empty?
+          else
+            reflection = relation.klass.reflect_on_all_associations.find do |r|
+              r.class_name == other.klass.name
+            end || return
 
-          unless other.preload_values.empty?
-            relation.preload! reflection.name => other.preload_values
-          end
+            unless other.preload_values.empty?
+              relation.preload! reflection.name => other.preload_values
+            end
 
-          unless other.includes_values.empty?
-            relation.includes! reflection.name => other.includes_values
+            unless other.includes_values.empty?
+              relation.includes! reflection.name => other.includes_values
+            end
           end
         end
-      end
 
-      def merge_joins
-        return if other.joins_values.blank?
+        def merge_joins
+          return if other.joins_values.blank?
 
-        if other.klass == relation.klass
-          relation.joins!(*other.joins_values)
-        else
-          joins_dependency, rest = other.joins_values.partition do |join|
-            case join
-            when Hash, Symbol, Array
-              true
-            else
-              false
+          if other.klass == relation.klass
+            relation.joins!(*other.joins_values)
+          else
+            alias_tracker = nil
+            joins_dependency = other.joins_values.map do |join|
+              case join
+              when Hash, Symbol, Array
+                alias_tracker ||= other.alias_tracker
+                ActiveRecord::Associations::JoinDependency.new(
+                  other.klass, other.table, join, alias_tracker
+                )
+              else
+                join
+              end
             end
-          end
 
-          join_dependency = ActiveRecord::Associations::JoinDependency.new(other.klass,
-                                                                           joins_dependency,
-                                                                           [])
-          relation.joins! rest
-
-          @relation = relation.joins join_dependency
+            relation.joins!(*joins_dependency)
+          end
         end
-      end
 
-      def merge_multi_values
-        if other.reordering_value
-          # override any order specified in the original relation
-          relation.reorder! other.order_values
-        elsif other.order_values
-          # merge in order_values from relation
-          relation.order! other.order_values
+        def merge_multi_values
+          if other.reordering_value
+            # override any order specified in the original relation
+            relation.reorder! other.order_values
+          elsif other.order_values.any?
+            # merge in order_values from relation
+            relation.order! other.order_values
+          end
+
+          extensions = other.extensions - relation.extensions
+          relation.extending!(*extensions) if extensions.any?
         end
 
-        relation.extend(*other.extending_values) unless other.extending_values.blank?
-      end
+        def merge_single_values
+          relation.lock_value ||= other.lock_value if other.lock_value
 
-      def merge_single_values
-        if relation.from_clause.empty?
-          relation.from_clause = other.from_clause
+          unless other.create_with_value.blank?
+            relation.create_with_value = (relation.create_with_value || {}).merge(other.create_with_value)
+          end
         end
-        relation.lock_value ||= other.lock_value
 
-        unless other.create_with_value.blank?
-          relation.create_with_value = (relation.create_with_value || {}).merge(other.create_with_value)
-        end
-      end
+        def merge_clauses
+          if relation.from_clause.empty? && !other.from_clause.empty?
+            relation.from_clause = other.from_clause
+          end
 
-      CLAUSE_METHOD_NAMES = CLAUSE_METHODS.map do |name|
-        ["#{name}_clause", "#{name}_clause="]
-      end
+          where_clause = relation.where_clause.merge(other.where_clause)
+          relation.where_clause = where_clause unless where_clause.empty?
 
-      def merge_clauses
-        CLAUSE_METHOD_NAMES.each do |(reader, writer)|
-          clause = relation.send(reader)
-          other_clause = other.send(reader)
-          relation.send(writer, clause.merge(other_clause))
+          having_clause = relation.having_clause.merge(other.having_clause)
+          relation.having_clause = having_clause unless having_clause.empty?
         end
-      end
     end
   end
 end
diff --git a/activerecord/lib/active_record/relation/predicate_builder.rb b/activerecord/lib/active_record/relation/predicate_builder.rb
index ecce949370..885c26d7aa 100644
--- a/activerecord/lib/active_record/relation/predicate_builder.rb
+++ b/activerecord/lib/active_record/relation/predicate_builder.rb
@@ -1,14 +1,7 @@
+# frozen_string_literal: true
+
 module ActiveRecord
   class PredicateBuilder # :nodoc:
-    require 'active_record/relation/predicate_builder/array_handler'
-    require 'active_record/relation/predicate_builder/association_query_handler'
-    require 'active_record/relation/predicate_builder/base_handler'
-    require 'active_record/relation/predicate_builder/basic_object_handler'
-    require 'active_record/relation/predicate_builder/class_handler'
-    require 'active_record/relation/predicate_builder/polymorphic_array_handler'
-    require 'active_record/relation/predicate_builder/range_handler'
-    require 'active_record/relation/predicate_builder/relation_handler'
-
     delegate :resolve_column_aliases, to: :table
 
     def initialize(table)
@@ -16,14 +9,11 @@ module ActiveRecord
       @handlers = []
 
       register_handler(BasicObject, BasicObjectHandler.new(self))
-      register_handler(Class, ClassHandler.new(self))
       register_handler(Base, BaseHandler.new(self))
       register_handler(Range, RangeHandler.new(self))
-      register_handler(RangeHandler::RangeWithBinds, RangeHandler.new(self))
       register_handler(Relation, RelationHandler.new)
       register_handler(Array, ArrayHandler.new(self))
-      register_handler(AssociationQueryValue, AssociationQueryHandler.new(self))
-      register_handler(PolymorphicArrayValue, PolymorphicArrayHandler.new(self))
+      register_handler(Set, ArrayHandler.new(self))
     end
 
     def build_from_hash(attributes)
@@ -31,28 +21,13 @@ module ActiveRecord
       expand_from_hash(attributes)
     end
 
-    def create_binds(attributes)
-      attributes = convert_dot_notation_to_hash(attributes)
-      create_binds_for_hash(attributes)
-    end
-
-    def expand(column, value)
-      # Find the foreign key when using queries such as:
-      # Post.where(author: author)
-      #
-      # For polymorphic relationships, find the foreign key and type:
-      # PriceEstimate.where(estimate_of: treasure)
-      value = AssociationQueryHandler.value_for(table, column, value) if table.associated_with?(column)
-      build(table.arel_attribute(column), value)
-    end
-
     def self.references(attributes)
       attributes.map do |key, value|
         if value.is_a?(Hash)
           key
         else
           key = key.to_s
-          key.split('.'.freeze).first if key.include?('.'.freeze)
+          key.split(".".freeze).first if key.include?(".".freeze)
         end
       end.compact
     end
@@ -76,93 +51,84 @@ module ActiveRecord
       handler_for(value).call(attribute, value)
     end
 
-    protected
-
-    attr_reader :table
-
-    def expand_from_hash(attributes)
-      return ["1=0"] if attributes.empty?
-
-      attributes.flat_map do |key, value|
-        if value.is_a?(Hash)
-          associated_predicate_builder(key).expand_from_hash(value)
-        else
-          expand(key, value)
-        end
-      end
+    def build_bind_attribute(column_name, value)
+      attr = Relation::QueryAttribute.new(column_name.to_s, value, table.type(column_name))
+      Arel::Nodes::BindParam.new(attr)
     end
 
+    protected
 
-    def create_binds_for_hash(attributes)
-      result = attributes.dup
-      binds = []
-
-      attributes.each do |column_name, value|
-        case value
-        when Hash
-          attrs, bvs = associated_predicate_builder(column_name).create_binds_for_hash(value)
-          result[column_name] = attrs
-          binds += bvs
-        when Relation
-          binds += value.bound_attributes
-        when Range
-          first = value.begin
-          last = value.end
-          unless first.respond_to?(:infinite?) && first.infinite?
-            binds << build_bind_param(column_name, first)
-            first = Arel::Nodes::BindParam.new
-          end
-          unless last.respond_to?(:infinite?) && last.infinite?
-            binds << build_bind_param(column_name, last)
-            last = Arel::Nodes::BindParam.new
-          end
-
-          result[column_name] = RangeHandler::RangeWithBinds.new(first, last, value.exclude_end?)
-        else
-          if can_be_bound?(column_name, value)
-            result[column_name] = Arel::Nodes::BindParam.new
-            binds << build_bind_param(column_name, value)
+      attr_reader :table
+
+      def expand_from_hash(attributes)
+        return ["1=0"] if attributes.empty?
+
+        attributes.flat_map do |key, value|
+          if value.is_a?(Hash) && !table.has_column?(key)
+            associated_predicate_builder(key).expand_from_hash(value)
+          elsif table.associated_with?(key)
+            # Find the foreign key when using queries such as:
+            # Post.where(author: author)
+            #
+            # For polymorphic relationships, find the foreign key and type:
+            # PriceEstimate.where(estimate_of: treasure)
+            associated_table = table.associated_table(key)
+            if associated_table.polymorphic_association?
+              case value.is_a?(Array) ? value.first : value
+              when Base, Relation
+                value = [value] unless value.is_a?(Array)
+                klass = PolymorphicArrayValue
+              end
+            end
+
+            klass ||= AssociationQueryValue
+            queries = klass.new(associated_table, value).queries.map do |query|
+              expand_from_hash(query).reduce(&:and)
+            end
+            queries.reduce(&:or)
+          # FIXME: Deprecate this and provide a public API to force equality
+          elsif (value.is_a?(Range) || value.is_a?(Array)) &&
+            table.type(key.to_s).respond_to?(:subtype)
+            BasicObjectHandler.new(self).call(table.arel_attribute(key), value)
+          else
+            build(table.arel_attribute(key), value)
           end
         end
       end
 
-      [result, binds]
-    end
-
     private
 
-    def associated_predicate_builder(association_name)
-      self.class.new(table.associated_table(association_name))
-    end
-
-    def convert_dot_notation_to_hash(attributes)
-      dot_notation = attributes.select do |k, v|
-        k.include?(".".freeze) && !v.is_a?(Hash)
+      def associated_predicate_builder(association_name)
+        self.class.new(table.associated_table(association_name))
       end
 
-      dot_notation.each_key do |key|
-        table_name, column_name = key.split(".".freeze)
-        value = attributes.delete(key)
-        attributes[table_name] ||= {}
-
-        attributes[table_name] = attributes[table_name].merge(column_name => value)
-      end
+      def convert_dot_notation_to_hash(attributes)
+        dot_notation = attributes.select do |k, v|
+          k.include?(".".freeze) && !v.is_a?(Hash)
+        end
 
-      attributes
-    end
+        dot_notation.each_key do |key|
+          table_name, column_name = key.split(".".freeze)
+          value = attributes.delete(key)
+          attributes[table_name] ||= {}
 
-    def handler_for(object)
-      @handlers.detect { |klass, _| klass === object }.last
-    end
+          attributes[table_name] = attributes[table_name].merge(column_name => value)
+        end
 
-    def can_be_bound?(column_name, value)
-      !value.nil? &&
-        handler_for(value).is_a?(BasicObjectHandler) &&
-        !table.associated_with?(column_name)
-    end
+        attributes
+      end
 
-    def build_bind_param(column_name, value)
-      Relation::QueryAttribute.new(column_name.to_s, value, table.type(column_name))
-    end
+      def handler_for(object)
+        @handlers.detect { |klass, _| klass === object }.last
+      end
   end
 end
+
+require "active_record/relation/predicate_builder/array_handler"
+require "active_record/relation/predicate_builder/base_handler"
+require "active_record/relation/predicate_builder/basic_object_handler"
+require "active_record/relation/predicate_builder/range_handler"
+require "active_record/relation/predicate_builder/relation_handler"
+
+require "active_record/relation/predicate_builder/association_query_value"
+require "active_record/relation/predicate_builder/polymorphic_array_value"
diff --git a/activerecord/lib/active_record/relation/predicate_builder/array_handler.rb b/activerecord/lib/active_record/relation/predicate_builder/array_handler.rb
index 95dbd6a77f..2fd75c8958 100644
--- a/activerecord/lib/active_record/relation/predicate_builder/array_handler.rb
+++ b/activerecord/lib/active_record/relation/predicate_builder/array_handler.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActiveRecord
   class PredicateBuilder
     class ArrayHandler # :nodoc:
@@ -6,18 +8,21 @@ module ActiveRecord
       end
 
       def call(attribute, value)
+        return attribute.in([]) if value.empty?
+
         values = value.map { |x| x.is_a?(Base) ? x.id : x }
         nils, values = values.partition(&:nil?)
-
-        return attribute.in([]) if values.empty? && nils.empty?
-
         ranges, values = values.partition { |v| v.is_a?(Range) }
 
         values_predicate =
           case values.length
           when 0 then NullPredicate
           when 1 then predicate_builder.build(attribute, values.first)
-          else attribute.in(values)
+          else
+            bind_values = values.map do |v|
+              predicate_builder.build_bind_attribute(attribute.name, v)
+            end
+            attribute.in(bind_values)
           end
 
         unless nils.empty?
@@ -26,18 +31,18 @@ module ActiveRecord
 
         array_predicates = ranges.map { |range| predicate_builder.build(attribute, range) }
         array_predicates.unshift(values_predicate)
-        array_predicates.inject { |composite, predicate| composite.or(predicate) }
+        array_predicates.inject(&:or)
       end
 
       protected
 
-      attr_reader :predicate_builder
+        attr_reader :predicate_builder
 
-      module NullPredicate # :nodoc:
-        def self.or(other)
-          other
+        module NullPredicate # :nodoc:
+          def self.or(other)
+            other
+          end
         end
-      end
     end
   end
 end
diff --git a/activerecord/lib/active_record/relation/predicate_builder/association_query_handler.rb b/activerecord/lib/active_record/relation/predicate_builder/association_query_handler.rb
deleted file mode 100644
index 413cb9fd84..0000000000
--- a/activerecord/lib/active_record/relation/predicate_builder/association_query_handler.rb
+++ /dev/null
@@ -1,89 +0,0 @@
-module ActiveRecord
-  class PredicateBuilder
-    class AssociationQueryHandler # :nodoc:
-      def self.value_for(table, column, value)
-        associated_table = table.associated_table(column)
-        klass = if associated_table.polymorphic_association? && ::Array === value && value.first.is_a?(Base)
-          PolymorphicArrayValue
-        else
-          AssociationQueryValue
-        end
-
-        klass.new(associated_table, value)
-      end
-
-      def initialize(predicate_builder)
-        @predicate_builder = predicate_builder
-      end
-
-      def call(attribute, value)
-        queries = {}
-
-        table = value.associated_table
-        if value.base_class
-          queries[table.association_foreign_type.to_s] = value.base_class.name
-        end
-
-        queries[table.association_foreign_key.to_s] = value.ids
-        predicate_builder.build_from_hash(queries)
-      end
-
-      protected
-
-      attr_reader :predicate_builder
-    end
-
-    class AssociationQueryValue # :nodoc:
-      attr_reader :associated_table, :value
-
-      def initialize(associated_table, value)
-        @associated_table = associated_table
-        @value = value
-      end
-
-      def ids
-        case value
-        when Relation
-          value.select(primary_key)
-        when Array
-          value.map { |v| convert_to_id(v) }
-        else
-          convert_to_id(value)
-        end
-      end
-
-      def base_class
-        if associated_table.polymorphic_association?
-          @base_class ||= polymorphic_base_class_from_value
-        end
-      end
-
-      private
-
-      def primary_key
-        associated_table.association_primary_key(base_class)
-      end
-
-      def polymorphic_base_class_from_value
-        case value
-        when Relation
-          value.klass.base_class
-        when Array
-          val = value.compact.first
-          val.class.base_class if val.is_a?(Base)
-        when Base
-          value.class.base_class
-        end
-      end
-
-      def convert_to_id(value)
-        case value
-        when Base
-          value._read_attribute(primary_key)
-        else
-          value
-        end
-      end
-    end
-  end
-end
diff --git a/activerecord/lib/active_record/relation/predicate_builder/association_query_value.rb b/activerecord/lib/active_record/relation/predicate_builder/association_query_value.rb
new file mode 100644
index 0000000000..28c7483c95
--- /dev/null
+++ b/activerecord/lib/active_record/relation/predicate_builder/association_query_value.rb
@@ -0,0 +1,46 @@
+# frozen_string_literal: true
+
+module ActiveRecord
+  class PredicateBuilder
+    class AssociationQueryValue # :nodoc:
+      def initialize(associated_table, value)
+        @associated_table = associated_table
+        @value = value
+      end
+
+      def queries
+        [associated_table.association_join_foreign_key.to_s => ids]
+      end
+
+      # TODO Change this to private once we've dropped Ruby 2.2 support.
+      # Workaround for Ruby 2.2 "private attribute?" warning.
+      protected
+        attr_reader :associated_table, :value
+
+      private
+        def ids
+          case value
+          when Relation
+            value.select_values.empty? ? value.select(primary_key) : value
+          when Array
+            value.map { |v| convert_to_id(v) }
+          else
+            convert_to_id(value)
+          end
+        end
+
+        def primary_key
+          associated_table.association_join_primary_key
+        end
+
+        def convert_to_id(value)
+          case value
+          when Base
+            value._read_attribute(primary_key)
+          else
+            value
+          end
+        end
+    end
+  end
+end
diff --git a/activerecord/lib/active_record/relation/predicate_builder/base_handler.rb b/activerecord/lib/active_record/relation/predicate_builder/base_handler.rb
index 6fa5b16f73..112821135f 100644
--- a/activerecord/lib/active_record/relation/predicate_builder/base_handler.rb
+++ b/activerecord/lib/active_record/relation/predicate_builder/base_handler.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActiveRecord
   class PredicateBuilder
     class BaseHandler # :nodoc:
@@ -11,7 +13,7 @@ module ActiveRecord
 
       protected
 
-      attr_reader :predicate_builder
+        attr_reader :predicate_builder
     end
   end
 end
diff --git a/activerecord/lib/active_record/relation/predicate_builder/basic_object_handler.rb b/activerecord/lib/active_record/relation/predicate_builder/basic_object_handler.rb
index 6cec75dc0a..34db266f05 100644
--- a/activerecord/lib/active_record/relation/predicate_builder/basic_object_handler.rb
+++ b/activerecord/lib/active_record/relation/predicate_builder/basic_object_handler.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActiveRecord
   class PredicateBuilder
     class BasicObjectHandler # :nodoc:
@@ -6,12 +8,13 @@ module ActiveRecord
       end
 
       def call(attribute, value)
-        attribute.eq(value)
+        bind = predicate_builder.build_bind_attribute(attribute.name, value)
+        attribute.eq(bind)
       end
 
       protected
 
-      attr_reader :predicate_builder
+        attr_reader :predicate_builder
     end
   end
 end
diff --git a/activerecord/lib/active_record/relation/predicate_builder/class_handler.rb b/activerecord/lib/active_record/relation/predicate_builder/class_handler.rb
deleted file mode 100644
index ed313fc9d4..0000000000
--- a/activerecord/lib/active_record/relation/predicate_builder/class_handler.rb
+++ /dev/null
@@ -1,27 +0,0 @@
-module ActiveRecord
-  class PredicateBuilder
-    class ClassHandler # :nodoc:
-      def initialize(predicate_builder)
-        @predicate_builder = predicate_builder
-      end
-
-      def call(attribute, value)
-        print_deprecation_warning
-        predicate_builder.build(attribute, value.name)
-      end
-
-      protected
-
-      attr_reader :predicate_builder
-
-      private
-
-      def print_deprecation_warning
-        ActiveSupport::Deprecation.warn(<<-MSG.squish)
-          Passing a class as a value in an Active Record query is deprecated and
-          will be removed. Pass a string instead.
-        MSG
-      end
-    end
-  end
-end
diff --git a/activerecord/lib/active_record/relation/predicate_builder/polymorphic_array_handler.rb b/activerecord/lib/active_record/relation/predicate_builder/polymorphic_array_handler.rb
deleted file mode 100644
index b6c6240343..0000000000
--- a/activerecord/lib/active_record/relation/predicate_builder/polymorphic_array_handler.rb
+++ /dev/null
@@ -1,57 +0,0 @@
-module ActiveRecord
-  class PredicateBuilder
-    class PolymorphicArrayHandler # :nodoc:
-      def initialize(predicate_builder)
-        @predicate_builder = predicate_builder
-      end
-
-      def call(attribute, value)
-        table = value.associated_table
-        queries = value.type_to_ids_mapping.map do |type, ids|
-          { table.association_foreign_type.to_s => type, table.association_foreign_key.to_s => ids }
-        end
-
-        predicates = queries.map { |query| predicate_builder.build_from_hash(query) }
-
-        if predicates.size > 1
-          type_and_ids_predicates = predicates.map { |type_predicate, id_predicate| Arel::Nodes::Grouping.new(type_predicate.and(id_predicate)) }
-          type_and_ids_predicates.inject(&:or)
-        else
-          predicates.first
-        end
-      end
-
-      protected
-
-      attr_reader :predicate_builder
-    end
-
-    class PolymorphicArrayValue # :nodoc:
-      attr_reader :associated_table, :values
-
-      def initialize(associated_table, values)
-        @associated_table = associated_table
-        @values = values
-      end
-
-      def type_to_ids_mapping
-        default_hash = Hash.new { |hsh, key| hsh[key] = [] }
-        values.each_with_object(default_hash) { |value, hash| hash[base_class(value).name] << convert_to_id(value) }
-      end
-
-      private
-
-      def primary_key(value)
-        associated_table.association_primary_key(base_class(value))
-      end
-
-      def base_class(value)
-        value.class.base_class
-      end
-
-      def convert_to_id(value)
-        value._read_attribute(primary_key(value))
-      end
-    end
-  end
-end
diff --git a/activerecord/lib/active_record/relation/predicate_builder/polymorphic_array_value.rb b/activerecord/lib/active_record/relation/predicate_builder/polymorphic_array_value.rb
new file mode 100644
index 0000000000..e8e2f2c626
--- /dev/null
+++ b/activerecord/lib/active_record/relation/predicate_builder/polymorphic_array_value.rb
@@ -0,0 +1,54 @@
+# frozen_string_literal: true
+
+module ActiveRecord
+  class PredicateBuilder
+    class PolymorphicArrayValue # :nodoc:
+      def initialize(associated_table, values)
+        @associated_table = associated_table
+        @values = values
+      end
+
+      def queries
+        type_to_ids_mapping.map do |type, ids|
+          {
+            associated_table.association_foreign_type.to_s => type,
+            associated_table.association_foreign_key.to_s => ids
+          }
+        end
+      end
+
+      # TODO Change this to private once we've dropped Ruby 2.2 support.
+      # Workaround for Ruby 2.2 "private attribute?" warning.
+      protected
+        attr_reader :associated_table, :values
+
+      private
+        def type_to_ids_mapping
+          default_hash = Hash.new { |hsh, key| hsh[key] = [] }
+          values.each_with_object(default_hash) { |value, hash| hash[base_class(value).name] << convert_to_id(value) }
+        end
+
+        def primary_key(value)
+          associated_table.association_join_primary_key(base_class(value))
+        end
+
+        def base_class(value)
+          case value
+          when Base
+            value.class.base_class
+          when Relation
+            value.klass.base_class
+          end
+        end
+
+        def convert_to_id(value)
+          case value
+          when Base
+            value._read_attribute(primary_key(value))
+          when Relation
+            value.select(primary_key(value))
+          end
+        end
+    end
+  end
+end
diff --git a/activerecord/lib/active_record/relation/predicate_builder/range_handler.rb b/activerecord/lib/active_record/relation/predicate_builder/range_handler.rb
index 306d4694ae..6d16579708 100644
--- a/activerecord/lib/active_record/relation/predicate_builder/range_handler.rb
+++ b/activerecord/lib/active_record/relation/predicate_builder/range_handler.rb
@@ -1,33 +1,41 @@
+# frozen_string_literal: true
+
 module ActiveRecord
   class PredicateBuilder
     class RangeHandler # :nodoc:
-      RangeWithBinds = Struct.new(:begin, :end, :exclude_end?)
+      class RangeWithBinds < Struct.new(:begin, :end)
+        def exclude_end?
+          false
+        end
+      end
 
       def initialize(predicate_builder)
         @predicate_builder = predicate_builder
       end
 
       def call(attribute, value)
+        begin_bind = predicate_builder.build_bind_attribute(attribute.name, value.begin)
+        end_bind = predicate_builder.build_bind_attribute(attribute.name, value.end)
         if value.begin.respond_to?(:infinite?) && value.begin.infinite?
           if value.end.respond_to?(:infinite?) && value.end.infinite?
             attribute.not_in([])
           elsif value.exclude_end?
-            attribute.lt(value.end)
+            attribute.lt(end_bind)
           else
-            attribute.lteq(value.end)
+            attribute.lteq(end_bind)
           end
         elsif value.end.respond_to?(:infinite?) && value.end.infinite?
-          attribute.gteq(value.begin)
+          attribute.gteq(begin_bind)
         elsif value.exclude_end?
-          attribute.gteq(value.begin).and(attribute.lt(value.end))
+          attribute.gteq(begin_bind).and(attribute.lt(end_bind))
         else
-          attribute.between(value)
+          attribute.between(RangeWithBinds.new(begin_bind, end_bind))
         end
       end
 
       protected
 
-      attr_reader :predicate_builder
+        attr_reader :predicate_builder
     end
   end
 end
diff --git a/activerecord/lib/active_record/relation/predicate_builder/relation_handler.rb b/activerecord/lib/active_record/relation/predicate_builder/relation_handler.rb
index 8a910a82fe..c8bbfa5051 100644
--- a/activerecord/lib/active_record/relation/predicate_builder/relation_handler.rb
+++ b/activerecord/lib/active_record/relation/predicate_builder/relation_handler.rb
@@ -1,7 +1,13 @@
+# frozen_string_literal: true
+
 module ActiveRecord
   class PredicateBuilder
     class RelationHandler # :nodoc:
       def call(attribute, value)
+        if value.eager_loading?
+          value = value.send(:apply_join_dependency)
+        end
+
         if value.select_values.empty?
           value = value.select(value.arel_attribute(value.klass.primary_key))
         end
diff --git a/activerecord/lib/active_record/relation/query_attribute.rb b/activerecord/lib/active_record/relation/query_attribute.rb
index 7ba964e802..3532f28858 100644
--- a/activerecord/lib/active_record/relation/query_attribute.rb
+++ b/activerecord/lib/active_record/relation/query_attribute.rb
@@ -1,8 +1,10 @@
-require 'active_record/attribute'
+# frozen_string_literal: true
+
+require "active_model/attribute"
 
 module ActiveRecord
   class Relation
-    class QueryAttribute < Attribute # :nodoc:
+    class QueryAttribute < ActiveModel::Attribute # :nodoc:
       def type_cast(value)
         value
       end
@@ -14,6 +16,11 @@ module ActiveRecord
       def with_cast_value(value)
         QueryAttribute.new(name, value, type)
       end
+
+      def nil?
+        !value_before_type_cast.is_a?(StatementCache::Substitute) &&
+          (value_before_type_cast.nil? || value_for_database.nil?)
+      end
     end
   end
 end
diff --git a/activerecord/lib/active_record/relation/query_methods.rb b/activerecord/lib/active_record/relation/query_methods.rb
index 8a87015e44..0296101f81 100644
--- a/activerecord/lib/active_record/relation/query_methods.rb
+++ b/activerecord/lib/active_record/relation/query_methods.rb
@@ -1,9 +1,10 @@
+# frozen_string_literal: true
+
 require "active_record/relation/from_clause"
 require "active_record/relation/query_attribute"
 require "active_record/relation/where_clause"
 require "active_record/relation/where_clause_factory"
-require 'active_model/forbidden_attributes_protection'
-require 'active_support/core_ext/string/filters'
+require "active_model/forbidden_attributes_protection"
 
 module ActiveRecord
   module QueryMethods
@@ -55,79 +56,26 @@ module ActiveRecord
     end
 
     FROZEN_EMPTY_ARRAY = [].freeze
-    Relation::MULTI_VALUE_METHODS.each do |name|
-      class_eval <<-CODE, __FILE__, __LINE__ + 1
-        def #{name}_values
-          @values[:#{name}] || FROZEN_EMPTY_ARRAY
-        end
+    FROZEN_EMPTY_HASH = {}.freeze
 
-        def #{name}_values=(values)
-          assert_mutability!
-          @values[:#{name}] = values
+    Relation::VALUE_METHODS.each do |name|
+      method_name = \
+        case name
+        when *Relation::MULTI_VALUE_METHODS then "#{name}_values"
+        when *Relation::SINGLE_VALUE_METHODS then "#{name}_value"
+        when *Relation::CLAUSE_METHODS then "#{name}_clause"
         end
-      CODE
-    end
-
-    (Relation::SINGLE_VALUE_METHODS - [:create_with]).each do |name|
       class_eval <<-CODE, __FILE__, __LINE__ + 1
-        def #{name}_value                    # def readonly_value
-          @values[:#{name}]                  #   @values[:readonly]
+        def #{method_name}                   # def includes_values
+          get_value(#{name.inspect})         #   get_value(:includes)
         end                                  # end
-      CODE
-    end
 
-    Relation::SINGLE_VALUE_METHODS.each do |name|
-      class_eval <<-CODE, __FILE__, __LINE__ + 1
-        def #{name}_value=(value)            # def readonly_value=(value)
-          assert_mutability!                 #   assert_mutability!
-          @values[:#{name}] = value          #   @values[:readonly] = value
+        def #{method_name}=(value)           # def includes_values=(value)
+          set_value(#{name.inspect}, value)  #   set_value(:includes, value)
         end                                  # end
       CODE
     end
 
-    Relation::CLAUSE_METHODS.each do |name|
-      class_eval <<-CODE, __FILE__, __LINE__ + 1
-        def #{name}_clause                           # def where_clause
-          @values[:#{name}] || new_#{name}_clause    #   @values[:where] || new_where_clause
-        end                                          # end
-                                                     #
-        def #{name}_clause=(value)                   # def where_clause=(value)
-          assert_mutability!                         #   assert_mutability!
-          @values[:#{name}] = value                  #   @values[:where] = value
-        end                                          # end
-      CODE
-    end
-
-    def bound_attributes
-      if limit_value && !string_containing_comma?(limit_value)
-        limit_bind = Attribute.with_cast_value(
-          "LIMIT".freeze,
-          connection.sanitize_limit(limit_value),
-          Type::Value.new,
-        )
-      end
-      if offset_value
-        offset_bind = Attribute.with_cast_value(
-          "OFFSET".freeze,
-          offset_value.to_i,
-          Type::Value.new,
-        )
-      end
-      connection.combine_bind_parameters(
-        from_clause: from_clause.binds,
-        join_clause: arel.bind_values,
-        where_clause: where_clause.binds,
-        having_clause: having_clause.binds,
-        limit: limit_bind,
-        offset: offset_bind,
-      )
-    end
-
-    FROZEN_EMPTY_HASH = {}.freeze
-    def create_with_value # :nodoc:
-      @values[:create_with] || FROZEN_EMPTY_HASH
-    end
-
     alias extensions extending_values
 
     # Specify relationships to be included in the result set. For
@@ -231,12 +179,13 @@ module ActiveRecord
 
     # Works in two unique ways.
     #
-    # First: takes a block so it can be used just like +Array#select+.
+    # First: takes a block so it can be used just like <tt>Array#select</tt>.
     #
     #   Model.all.select { |m| m.field == value }
     #
     # This will build an array of objects from the database for the scope,
-    # converting them into an array and iterating through them using +Array#select+.
+    # converting them into an array and iterating through them using
+    # <tt>Array#select</tt>.
     #
     # Second: Modifies the SELECT statement for the query so that only certain
     # fields are retrieved:
@@ -269,8 +218,15 @@ module ActiveRecord
     #   Model.select(:field).first.other_field
     #   # => ActiveModel::MissingAttributeError: missing attribute: other_field
     def select(*fields)
-      return super if block_given?
-      raise ArgumentError, 'Call this with at least one field' if fields.empty?
+      if block_given?
+        if fields.any?
+          raise ArgumentError, "`select' with block doesn't take arguments."
+        end
+
+        return super()
+      end
+
+      raise ArgumentError, "Call `select' with at least one field" if fields.empty?
       spawn._select!(*fields)
     end
 
@@ -339,6 +295,7 @@ module ActiveRecord
       spawn.order!(*args)
     end
 
+    # Same as #order but operates on relation in-place instead of copying.
     def order!(*args) # :nodoc:
       preprocess_order_args(args)
 
@@ -360,6 +317,7 @@ module ActiveRecord
       spawn.reorder!(*args)
     end
 
+    # Same as #reorder but operates on relation in-place instead of copying.
     def reorder!(*args) # :nodoc:
       preprocess_order_args(args)
 
@@ -417,7 +375,10 @@ module ActiveRecord
       args.each do |scope|
         case scope
         when Symbol
-          symbol_unscoping(scope)
+          if !VALID_UNSCOPING_VALUES.include?(scope)
+            raise ArgumentError, "Called unscope() with invalid unscoping argument ':#{scope}'. Valid arguments are :#{VALID_UNSCOPING_VALUES.to_a.join(", :")}."
+          end
+          set_value(scope, nil)
         when Hash
           scope.each do |key, target_value|
             if key != :where
@@ -482,20 +443,17 @@ module ActiveRecord
     #   => SELECT "users".* FROM "users" LEFT OUTER JOIN "posts" ON "posts"."user_id" = "users"."id"
     #
     def left_outer_joins(*args)
-      check_if_method_has_arguments!(:left_outer_joins, args)
-
-      args.compact!
-      args.flatten!
-
+      check_if_method_has_arguments!(__callee__, args)
       spawn.left_outer_joins!(*args)
     end
     alias :left_joins :left_outer_joins
 
     def left_outer_joins!(*args) # :nodoc:
+      args.compact!
+      args.flatten!
       self.left_outer_joins_values += args
       self
     end
-    alias :left_joins! :left_outer_joins!
 
     # Returns a new relation, which is the result of filtering the current relation
     # according to the conditions in the arguments.
@@ -676,7 +634,8 @@ module ActiveRecord
       end
 
       self.where_clause = self.where_clause.or(other.where_clause)
-      self.having_clause = self.having_clause.or(other.having_clause)
+      self.having_clause = having_clause.or(other.having_clause)
+      self.references_values += other.references_values
 
       self
     end
@@ -707,13 +666,6 @@ module ActiveRecord
     end
 
     def limit!(value) # :nodoc:
-      if string_containing_comma?(value)
-        # Remove `string_containing_comma?` when removing this deprecation
-        ActiveSupport::Deprecation.warn(<<-WARNING.squish)
-          Passing a string to limit in the form "1,2" is deprecated and will be
-          removed in Rails 5.1. Please call `offset` explicitly instead.
-        WARNING
-      end
       self.limit_value = value
       self
     end
@@ -780,7 +732,7 @@ module ActiveRecord
     #   end
     #
     def none
-      where("1=0").extending!(NullRelation)
+      spawn.none!
     end
 
     def none! # :nodoc:
@@ -824,7 +776,7 @@ module ActiveRecord
         value = sanitize_forbidden_attributes(value)
         self.create_with_value = create_with_value.merge(value)
       else
-        self.create_with_value = {}
+        self.create_with_value = FROZEN_EMPTY_HASH
       end
 
       self
@@ -865,16 +817,12 @@ module ActiveRecord
     def distinct(value = true)
       spawn.distinct!(value)
     end
-    alias uniq distinct
-    deprecate uniq: :distinct
 
     # Like #distinct, but modifies relation in place.
     def distinct!(value = true) # :nodoc:
       self.distinct_value = value
       self
     end
-    alias uniq! distinct!
-    deprecate uniq!: :distinct!
 
     # Used to extend a scope with additional methods, either through
     # a module or through a block provided.
@@ -944,293 +892,322 @@ module ActiveRecord
       self
     end
 
-    # Returns the Arel object associated with the relation.
-    def arel # :nodoc:
-      @arel ||= build_arel
+    def skip_query_cache! # :nodoc:
+      self.skip_query_cache_value = true
+      self
     end
 
-    private
-
-    def assert_mutability!
-      raise ImmutableRelation if @loaded
-      raise ImmutableRelation if defined?(@arel) && @arel
+    # Returns the Arel object associated with the relation.
+    def arel(aliases = nil) # :nodoc:
+      @arel ||= build_arel(aliases)
     end
 
-    def build_arel
-      arel = Arel::SelectManager.new(table)
-
-      build_joins(arel, joins_values.flatten) unless joins_values.empty?
-      build_left_outer_joins(arel, left_outer_joins_values.flatten) unless left_outer_joins_values.empty?
-
-      arel.where(where_clause.ast) unless where_clause.empty?
-      arel.having(having_clause.ast) unless having_clause.empty?
-      if limit_value
-        if string_containing_comma?(limit_value)
-          arel.take(connection.sanitize_limit(limit_value))
-        else
-          arel.take(Arel::Nodes::BindParam.new)
-        end
+    protected
+      # Returns a relation value with a given name
+      def get_value(name) # :nodoc:
+        @values[name] || default_value_for(name)
       end
-      arel.skip(Arel::Nodes::BindParam.new) if offset_value
-      arel.group(*arel_columns(group_values.uniq.reject(&:blank?))) unless group_values.empty?
-
-      build_order(arel)
 
-      build_select(arel)
-
-      arel.distinct(distinct_value)
-      arel.from(build_from) unless from_clause.empty?
-      arel.lock(lock_value) if lock_value
+      # Sets the relation value with the given name
+      def set_value(name, value) # :nodoc:
+        assert_mutability!
+        @values[name] = value
+      end
 
-      arel
-    end
+    private
 
-    def symbol_unscoping(scope)
-      if !VALID_UNSCOPING_VALUES.include?(scope)
-        raise ArgumentError, "Called unscope() with invalid unscoping argument ':#{scope}'. Valid arguments are :#{VALID_UNSCOPING_VALUES.to_a.join(", :")}."
+      def assert_mutability!
+        raise ImmutableRelation if @loaded
+        raise ImmutableRelation if defined?(@arel) && @arel
       end
 
-      clause_method = Relation::CLAUSE_METHODS.include?(scope)
-      multi_val_method = Relation::MULTI_VALUE_METHODS.include?(scope)
-      if clause_method
-        unscope_code = "#{scope}_clause="
-      else
-        unscope_code = "#{scope}_value#{'s' if multi_val_method}="
-      end
+      def build_arel(aliases)
+        arel = Arel::SelectManager.new(table)
+
+        aliases = build_joins(arel, joins_values.flatten, aliases) unless joins_values.empty?
+        build_left_outer_joins(arel, left_outer_joins_values.flatten, aliases) unless left_outer_joins_values.empty?
+
+        arel.where(where_clause.ast) unless where_clause.empty?
+        arel.having(having_clause.ast) unless having_clause.empty?
+        if limit_value
+          limit_attribute = ActiveModel::Attribute.with_cast_value(
+            "LIMIT".freeze,
+            connection.sanitize_limit(limit_value),
+            Type.default_value,
+          )
+          arel.take(Arel::Nodes::BindParam.new(limit_attribute))
+        end
+        if offset_value
+          offset_attribute = ActiveModel::Attribute.with_cast_value(
+            "OFFSET".freeze,
+            offset_value.to_i,
+            Type.default_value,
+          )
+          arel.skip(Arel::Nodes::BindParam.new(offset_attribute))
+        end
+        arel.group(*arel_columns(group_values.uniq.reject(&:blank?))) unless group_values.empty?
 
-      case scope
-      when :order
-        result = []
-      else
-        result = [] if multi_val_method
-      end
+        build_order(arel)
 
-      self.send(unscope_code, result)
-    end
+        build_select(arel)
 
-    def build_from
-      opts = from_clause.value
-      name = from_clause.name
-      case opts
-      when Relation
-        name ||= 'subquery'
-        opts.arel.as(name.to_s)
-      else
-        opts
+        arel.distinct(distinct_value)
+        arel.from(build_from) unless from_clause.empty?
+        arel.lock(lock_value) if lock_value
+
+        arel
       end
-    end
 
-    def build_left_outer_joins(manager, outer_joins)
-      buckets = outer_joins.group_by do |join|
-        case join
-        when Hash, Symbol, Array
-          :association_join
+      def build_from
+        opts = from_clause.value
+        name = from_clause.name
+        case opts
+        when Relation
+          if opts.eager_loading?
+            opts = opts.send(:apply_join_dependency)
+          end
+          name ||= "subquery"
+          opts.arel.as(name.to_s)
         else
-          raise ArgumentError, 'only Hash, Symbol and Array are allowed'
+          opts
         end
       end
 
-      build_join_query(manager, buckets, Arel::Nodes::OuterJoin)
-    end
-
-    def build_joins(manager, joins)
-      buckets = joins.group_by do |join|
-        case join
-        when String
-          :string_join
-        when Hash, Symbol, Array
-          :association_join
-        when ActiveRecord::Associations::JoinDependency
-          :stashed_join
-        when Arel::Nodes::Join
-          :join_node
-        else
-          raise 'unknown class: %s' % join.class.name
+      def build_left_outer_joins(manager, outer_joins, aliases)
+        buckets = outer_joins.group_by do |join|
+          case join
+          when Hash, Symbol, Array
+            :association_join
+          else
+            raise ArgumentError, "only Hash, Symbol and Array are allowed"
+          end
         end
-      end
 
-      build_join_query(manager, buckets, Arel::Nodes::InnerJoin)
-    end
+        build_join_query(manager, buckets, Arel::Nodes::OuterJoin, aliases)
+      end
 
-    def build_join_query(manager, buckets, join_type)
-      buckets.default = []
+      def build_joins(manager, joins, aliases)
+        buckets = joins.group_by do |join|
+          case join
+          when String
+            :string_join
+          when Hash, Symbol, Array
+            :association_join
+          when ActiveRecord::Associations::JoinDependency
+            :stashed_join
+          when Arel::Nodes::Join
+            :join_node
+          else
+            raise "unknown class: %s" % join.class.name
+          end
+        end
 
-      association_joins         = buckets[:association_join]
-      stashed_association_joins = buckets[:stashed_join]
-      join_nodes                = buckets[:join_node].uniq
-      string_joins              = buckets[:string_join].map(&:strip).uniq
+        build_join_query(manager, buckets, Arel::Nodes::InnerJoin, aliases)
+      end
 
-      join_list = join_nodes + convert_join_strings_to_ast(manager, string_joins)
+      def build_join_query(manager, buckets, join_type, aliases)
+        buckets.default = []
 
-      join_dependency = ActiveRecord::Associations::JoinDependency.new(
-        @klass,
-        association_joins,
-        join_list
-      )
+        association_joins         = buckets[:association_join]
+        stashed_association_joins = buckets[:stashed_join]
+        join_nodes                = buckets[:join_node].uniq
+        string_joins              = buckets[:string_join].map(&:strip).uniq
 
-      join_infos = join_dependency.join_constraints stashed_association_joins, join_type
+        join_list = join_nodes + convert_join_strings_to_ast(manager, string_joins)
+        alias_tracker = alias_tracker(join_list, aliases)
 
-      join_infos.each do |info|
-        info.joins.each { |join| manager.from(join) }
-        manager.bind_values.concat info.binds
-      end
+        join_dependency = ActiveRecord::Associations::JoinDependency.new(
+          klass, table, association_joins, alias_tracker
+        )
 
-      manager.join_sources.concat(join_list)
+        joins = join_dependency.join_constraints(stashed_association_joins, join_type)
+        joins.each { |join| manager.from(join) }
 
-      manager
-    end
+        manager.join_sources.concat(join_list)
 
-    def convert_join_strings_to_ast(table, joins)
-      joins
-        .flatten
-        .reject(&:blank?)
-        .map { |join| table.create_string_join(Arel.sql(join)) }
-    end
+        alias_tracker.aliases
+      end
 
-    def build_select(arel)
-      if select_values.any?
-        arel.project(*arel_columns(select_values.uniq))
-      else
-        arel.project(@klass.arel_table[Arel.star])
+      def convert_join_strings_to_ast(table, joins)
+        joins
+          .flatten
+          .reject(&:blank?)
+          .map { |join| table.create_string_join(Arel.sql(join)) }
       end
-    end
 
-    def arel_columns(columns)
-      columns.map do |field|
-        if (Symbol === field || String === field) && (klass.has_attribute?(field) || klass.attribute_alias?(field)) && !from_clause.value
-          arel_attribute(field)
-        elsif Symbol === field
-          connection.quote_table_name(field.to_s)
+      def build_select(arel)
+        if select_values.any?
+          arel.project(*arel_columns(select_values.uniq))
+        elsif klass.ignored_columns.any?
+          arel.project(*klass.column_names.map { |field| arel_attribute(field) })
         else
-          field
+          arel.project(table[Arel.star])
         end
       end
-    end
 
-    def reverse_sql_order(order_query)
-      if order_query.empty?
-        return [arel_attribute(primary_key).desc] if primary_key
-        raise IrreversibleOrderError,
-          "Relation has no current order and table has no primary key to be used as default order"
+      def arel_columns(columns)
+        columns.map do |field|
+          if (Symbol === field || String === field) && (klass.has_attribute?(field) || klass.attribute_alias?(field)) && !from_clause.value
+            arel_attribute(field)
+          elsif Symbol === field
+            connection.quote_table_name(field.to_s)
+          else
+            field
+          end
+        end
       end
 
-      order_query.flat_map do |o|
-        case o
-        when Arel::Attribute
-          o.desc
-        when Arel::Nodes::Ordering
-          o.reverse
-        when String
-          if does_not_support_reverse?(o)
-            raise IrreversibleOrderError, "Order #{o.inspect} can not be reversed automatically"
-          end
-          o.split(',').map! do |s|
-            s.strip!
-            s.gsub!(/\sasc\Z/i, ' DESC') || s.gsub!(/\sdesc\Z/i, ' ASC') || s.concat(' DESC')
+      def reverse_sql_order(order_query)
+        if order_query.empty?
+          return [arel_attribute(primary_key).desc] if primary_key
+          raise IrreversibleOrderError,
+            "Relation has no current order and table has no primary key to be used as default order"
+        end
+
+        order_query.flat_map do |o|
+          case o
+          when Arel::Attribute
+            o.desc
+          when Arel::Nodes::Ordering
+            o.reverse
+          when String
+            if does_not_support_reverse?(o)
+              raise IrreversibleOrderError, "Order #{o.inspect} can not be reversed automatically"
+            end
+            o.split(",").map! do |s|
+              s.strip!
+              s.gsub!(/\sasc\Z/i, " DESC") || s.gsub!(/\sdesc\Z/i, " ASC") || (s << " DESC")
+            end
+          else
+            o
           end
-        else
-          o
         end
       end
-    end
-
-    def does_not_support_reverse?(order)
-      #uses sql function with multiple arguments
-      order =~ /\([^()]*,[^()]*\)/ ||
-        # uses "nulls first" like construction
-        order =~ /nulls (first|last)\Z/i
-    end
 
-    def build_order(arel)
-      orders = order_values.uniq
-      orders.reject!(&:blank?)
+      def does_not_support_reverse?(order)
+        # Account for String subclasses like Arel::Nodes::SqlLiteral that
+        # override methods like #count.
+        order = String.new(order) unless order.instance_of?(String)
 
-      arel.order(*orders) unless orders.empty?
-    end
+        # Uses SQL function with multiple arguments.
+        (order.include?(",") && order.split(",").find { |section| section.count("(") != section.count(")") }) ||
+          # Uses "nulls first" like construction.
+          /nulls (first|last)\Z/i.match?(order)
+      end
 
-    VALID_DIRECTIONS = [:asc, :desc, :ASC, :DESC,
-                        'asc', 'desc', 'ASC', 'DESC'] # :nodoc:
+      def build_order(arel)
+        orders = order_values.uniq
+        orders.reject!(&:blank?)
 
-    def validate_order_args(args)
-      args.each do |arg|
-        next unless arg.is_a?(Hash)
-        arg.each do |_key, value|
-          raise ArgumentError, "Direction \"#{value}\" is invalid. Valid " \
-                               "directions are: #{VALID_DIRECTIONS.inspect}" unless VALID_DIRECTIONS.include?(value)
-        end
+        arel.order(*orders) unless orders.empty?
       end
-    end
 
-    def preprocess_order_args(order_args)
-      order_args.map! do |arg|
-        klass.send(:sanitize_sql_for_order, arg)
-      end
-      order_args.flatten!
-      validate_order_args(order_args)
+      VALID_DIRECTIONS = [:asc, :desc, :ASC, :DESC,
+                          "asc", "desc", "ASC", "DESC"].to_set # :nodoc:
 
-      references = order_args.grep(String)
-      references.map! { |arg| arg =~ /^([a-zA-Z]\w*)\.(\w+)/ && $1 }.compact!
-      references!(references) if references.any?
+      def validate_order_args(args)
+        args.each do |arg|
+          next unless arg.is_a?(Hash)
+          arg.each do |_key, value|
+            unless VALID_DIRECTIONS.include?(value)
+              raise ArgumentError,
+                "Direction \"#{value}\" is invalid. Valid directions are: #{VALID_DIRECTIONS.to_a.inspect}"
+            end
+          end
+        end
+      end
 
-      # if a symbol is given we prepend the quoted table name
-      order_args.map! do |arg|
-        case arg
-        when Symbol
-          arel_attribute(arg).asc
-        when Hash
-          arg.map { |field, dir|
-            arel_attribute(field).send(dir.downcase)
-          }
-        else
-          arg
+      def preprocess_order_args(order_args)
+        order_args.map! do |arg|
+          klass.sanitize_sql_for_order(arg)
         end
-      end.flatten!
-    end
+        order_args.flatten!
 
-    # Checks to make sure that the arguments are not blank. Note that if some
-    # blank-like object were initially passed into the query method, then this
-    # method will not raise an error.
-    #
-    # Example:
-    #
-    #    Post.references()   # raises an error
-    #    Post.references([]) # does not raise an error
-    #
-    # This particular method should be called with a method_name and the args
-    # passed into that method as an input. For example:
-    #
-    # def references(*args)
-    #   check_if_method_has_arguments!("references", args)
-    #   ...
-    # end
-    def check_if_method_has_arguments!(method_name, args)
-      if args.blank?
-        raise ArgumentError, "The method .#{method_name}() must contain arguments."
+        @klass.enforce_raw_sql_whitelist(
+          order_args.flat_map { |a| a.is_a?(Hash) ? a.keys : a },
+          whitelist: AttributeMethods::ClassMethods::COLUMN_NAME_ORDER_WHITELIST
+        )
+
+        validate_order_args(order_args)
+
+        references = order_args.grep(String)
+        references.map! { |arg| arg =~ /^\W?(\w+)\W?\./ && $1 }.compact!
+        references!(references) if references.any?
+
+        # if a symbol is given we prepend the quoted table name
+        order_args.map! do |arg|
+          case arg
+          when Symbol
+            arel_attribute(arg).asc
+          when Hash
+            arg.map { |field, dir|
+              case field
+              when Arel::Nodes::SqlLiteral
+                field.send(dir.downcase)
+              else
+                arel_attribute(field).send(dir.downcase)
+              end
+            }
+          else
+            arg
+          end
+        end.flatten!
       end
-    end
 
-    def structurally_incompatible_values_for_or(other)
-      Relation::SINGLE_VALUE_METHODS.reject { |m| send("#{m}_value") == other.send("#{m}_value") } +
-        (Relation::MULTI_VALUE_METHODS - [:extending]).reject { |m| send("#{m}_values") == other.send("#{m}_values") } +
-        (Relation::CLAUSE_METHODS - [:having, :where]).reject { |m| send("#{m}_clause") == other.send("#{m}_clause") }
-    end
+      # Checks to make sure that the arguments are not blank. Note that if some
+      # blank-like object were initially passed into the query method, then this
+      # method will not raise an error.
+      #
+      # Example:
+      #
+      #    Post.references()   # raises an error
+      #    Post.references([]) # does not raise an error
+      #
+      # This particular method should be called with a method_name and the args
+      # passed into that method as an input. For example:
+      #
+      # def references(*args)
+      #   check_if_method_has_arguments!("references", args)
+      #   ...
+      # end
+      def check_if_method_has_arguments!(method_name, args)
+        if args.blank?
+          raise ArgumentError, "The method .#{method_name}() must contain arguments."
+        end
+      end
 
-    def new_where_clause
-      Relation::WhereClause.empty
-    end
-    alias new_having_clause new_where_clause
+      STRUCTURAL_OR_METHODS = Relation::VALUE_METHODS - [:extending, :where, :having, :unscope, :references]
+      def structurally_incompatible_values_for_or(other)
+        STRUCTURAL_OR_METHODS.reject do |method|
+          get_value(method) == other.get_value(method)
+        end
+      end
 
-    def where_clause_factory
-      @where_clause_factory ||= Relation::WhereClauseFactory.new(klass, predicate_builder)
-    end
-    alias having_clause_factory where_clause_factory
+      def where_clause_factory
+        @where_clause_factory ||= Relation::WhereClauseFactory.new(klass, predicate_builder)
+      end
+      alias having_clause_factory where_clause_factory
+
+      DEFAULT_VALUES = {
+        create_with: FROZEN_EMPTY_HASH,
+        readonly: false,
+        where: Relation::WhereClause.empty,
+        having: Relation::WhereClause.empty,
+        from: Relation::FromClause.empty
+      }
+
+      Relation::MULTI_VALUE_METHODS.each do |value|
+        DEFAULT_VALUES[value] ||= FROZEN_EMPTY_ARRAY
+      end
 
-    def new_from_clause
-      Relation::FromClause.empty
-    end
+      Relation::SINGLE_VALUE_METHODS.each do |value|
+        DEFAULT_VALUES[value] = nil if DEFAULT_VALUES[value].nil?
+      end
 
-    def string_containing_comma?(value)
-      ::String === value && value.include?(",")
-    end
+      def default_value_for(name)
+        DEFAULT_VALUES.fetch(name) do
+          raise ArgumentError, "unknown relation value #{name.inspect}"
+        end
+      end
   end
 end
diff --git a/activerecord/lib/active_record/relation/record_fetch_warning.rb b/activerecord/lib/active_record/relation/record_fetch_warning.rb
index dbd08811fa..a7d07d23e1 100644
--- a/activerecord/lib/active_record/relation/record_fetch_warning.rb
+++ b/activerecord/lib/active_record/relation/record_fetch_warning.rb
@@ -1,16 +1,18 @@
+# frozen_string_literal: true
+
 module ActiveRecord
   class Relation
     module RecordFetchWarning
       # When this module is prepended to ActiveRecord::Relation and
-      # `config.active_record.warn_on_records_fetched_greater_than` is
+      # +config.active_record.warn_on_records_fetched_greater_than+ is
       # set to an integer, if the number of records a query returns is
-      # greater than the value of `warn_on_records_fetched_greater_than`,
+      # greater than the value of +warn_on_records_fetched_greater_than+,
       # a warning is logged. This allows for the detection of queries that
       # return a large number of records, which could cause memory bloat.
       #
       # In most cases, fetching large number of records can be performed
       # efficiently using the ActiveRecord::Batches methods.
-      # See active_record/lib/relation/batches.rb for more information.
+      # See ActiveRecord::Batches for more information.
       def exec_queries
         QueryRegistry.reset
 
diff --git a/activerecord/lib/active_record/relation/spawn_methods.rb b/activerecord/lib/active_record/relation/spawn_methods.rb
index d5c18a2a4a..617d8de8b2 100644
--- a/activerecord/lib/active_record/relation/spawn_methods.rb
+++ b/activerecord/lib/active_record/relation/spawn_methods.rb
@@ -1,10 +1,11 @@
-require 'active_support/core_ext/hash/except'
-require 'active_support/core_ext/hash/slice'
-require 'active_record/relation/merger'
+# frozen_string_literal: true
+
+require "active_support/core_ext/hash/except"
+require "active_support/core_ext/hash/slice"
+require "active_record/relation/merger"
 
 module ActiveRecord
   module SpawnMethods
-
     # This is overridden by Associations::CollectionProxy
     def spawn #:nodoc:
       clone
@@ -67,7 +68,7 @@ module ActiveRecord
 
     private
 
-      def relation_with(values) # :nodoc:
+      def relation_with(values)
         result = Relation.create(klass, table, predicate_builder, values)
         result.extend(*extending_values) if extending_values.any?
         result
diff --git a/activerecord/lib/active_record/relation/where_clause.rb b/activerecord/lib/active_record/relation/where_clause.rb
index 89396b518c..a502713e56 100644
--- a/activerecord/lib/active_record/relation/where_clause.rb
+++ b/activerecord/lib/active_record/relation/where_clause.rb
@@ -1,68 +1,63 @@
+# frozen_string_literal: true
+
 module ActiveRecord
   class Relation
     class WhereClause # :nodoc:
-      attr_reader :binds
-
       delegate :any?, :empty?, to: :predicates
 
-      def initialize(predicates, binds)
+      def initialize(predicates)
         @predicates = predicates
-        @binds = binds
       end
 
       def +(other)
         WhereClause.new(
           predicates + other.predicates,
-          binds + other.binds,
+        )
+      end
+
+      def -(other)
+        WhereClause.new(
+          predicates - other.predicates,
         )
       end
 
       def merge(other)
         WhereClause.new(
           predicates_unreferenced_by(other) + other.predicates,
-          non_conflicting_binds(other) + other.binds,
         )
       end
 
       def except(*columns)
-        WhereClause.new(
-          predicates_except(columns),
-          binds_except(columns),
-        )
+        WhereClause.new(except_predicates(columns))
       end
 
       def or(other)
-        if empty?
-          self
-        elsif other.empty?
-          other
+        left = self - other
+        common = self - left
+        right = other - common
+
+        if left.empty? || right.empty?
+          common
         else
-          WhereClause.new(
-            [ast.or(other.ast)],
-            binds + other.binds
+          or_clause = WhereClause.new(
+            [left.ast.or(right.ast)],
           )
+          common + or_clause
         end
       end
 
       def to_h(table_name = nil)
-        equalities = predicates.grep(Arel::Nodes::Equality)
+        equalities = equalities(predicates)
         if table_name
           equalities = equalities.select do |node|
             node.left.relation.name == table_name
           end
         end
 
-        binds = self.binds.map { |attr| [attr.name, attr.value] }.to_h
-
         equalities.map { |node|
-          name = node.left.name
-          [name, binds.fetch(name.to_s) {
-            case node.right
-            when Array then node.right.map(&:val)
-            when Arel::Nodes::Casted, Arel::Nodes::Quoted
-              node.right.val
-            end
-          }]
+          name = node.left.name.to_s
+          value = extract_node_value(node.right)
+          [name, value]
         }.to_h
       end
 
@@ -72,103 +67,120 @@ module ActiveRecord
 
       def ==(other)
         other.is_a?(WhereClause) &&
-          predicates == other.predicates &&
-          binds == other.binds
+          predicates == other.predicates
       end
 
       def invert
-        WhereClause.new(inverted_predicates, binds)
+        WhereClause.new(inverted_predicates)
       end
 
       def self.empty
-        @empty ||= new([], [])
+        @empty ||= new([])
       end
 
       protected
 
-      attr_reader :predicates
+        attr_reader :predicates
 
-      def referenced_columns
-        @referenced_columns ||= begin
-          equality_nodes = predicates.select { |n| equality_node?(n) }
-          Set.new(equality_nodes, &:left)
+        def referenced_columns
+          @referenced_columns ||= begin
+            equality_nodes = predicates.select { |n| equality_node?(n) }
+            Set.new(equality_nodes, &:left)
+          end
         end
-      end
 
       private
+        def equalities(predicates)
+          equalities = []
+
+          predicates.each do |node|
+            case node
+            when Arel::Nodes::Equality
+              equalities << node
+            when Arel::Nodes::And
+              equalities.concat equalities(node.children)
+            end
+          end
 
-      def predicates_unreferenced_by(other)
-        predicates.reject do |n|
-          equality_node?(n) && other.referenced_columns.include?(n.left)
+          equalities
         end
-      end
 
-      def equality_node?(node)
-        node.respond_to?(:operator) && node.operator == :==
-      end
-
-      def non_conflicting_binds(other)
-        conflicts = referenced_columns & other.referenced_columns
-        conflicts.map! { |node| node.name.to_s }
-        binds.reject { |attr| conflicts.include?(attr.name) }
-      end
+        def predicates_unreferenced_by(other)
+          predicates.reject do |n|
+            equality_node?(n) && other.referenced_columns.include?(n.left)
+          end
+        end
 
-      def inverted_predicates
-        predicates.map { |node| invert_predicate(node) }
-      end
+        def equality_node?(node)
+          node.respond_to?(:operator) && node.operator == :==
+        end
 
-      def invert_predicate(node)
-        case node
-        when NilClass
-          raise ArgumentError, 'Invalid argument for .where.not(), got nil.'
-        when Arel::Nodes::In
-          Arel::Nodes::NotIn.new(node.left, node.right)
-        when Arel::Nodes::Equality
-          Arel::Nodes::NotEqual.new(node.left, node.right)
-        when String
-          Arel::Nodes::Not.new(Arel::Nodes::SqlLiteral.new(node))
-        else
-          Arel::Nodes::Not.new(node)
+        def inverted_predicates
+          predicates.map { |node| invert_predicate(node) }
         end
-      end
 
-      def predicates_except(columns)
-        predicates.reject do |node|
+        def invert_predicate(node)
           case node
-          when Arel::Nodes::Between, Arel::Nodes::In, Arel::Nodes::NotIn, Arel::Nodes::Equality, Arel::Nodes::NotEqual, Arel::Nodes::LessThan, Arel::Nodes::LessThanOrEqual, Arel::Nodes::GreaterThan, Arel::Nodes::GreaterThanOrEqual
-            subrelation = (node.left.kind_of?(Arel::Attributes::Attribute) ? node.left : node.right)
-            columns.include?(subrelation.name.to_s)
+          when NilClass
+            raise ArgumentError, "Invalid argument for .where.not(), got nil."
+          when Arel::Nodes::In
+            Arel::Nodes::NotIn.new(node.left, node.right)
+          when Arel::Nodes::Equality
+            Arel::Nodes::NotEqual.new(node.left, node.right)
+          when String
+            Arel::Nodes::Not.new(Arel::Nodes::SqlLiteral.new(node))
+          else
+            Arel::Nodes::Not.new(node)
           end
         end
-      end
 
-      def binds_except(columns)
-        binds.reject do |attr|
-          columns.include?(attr.name)
+        def except_predicates(columns)
+          predicates.reject do |node|
+            case node
+            when Arel::Nodes::Between, Arel::Nodes::In, Arel::Nodes::NotIn, Arel::Nodes::Equality, Arel::Nodes::NotEqual, Arel::Nodes::LessThan, Arel::Nodes::LessThanOrEqual, Arel::Nodes::GreaterThan, Arel::Nodes::GreaterThanOrEqual
+              subrelation = (node.left.kind_of?(Arel::Attributes::Attribute) ? node.left : node.right)
+              columns.include?(subrelation.name.to_s)
+            end
+          end
         end
-      end
 
-      def predicates_with_wrapped_sql_literals
-        non_empty_predicates.map do |node|
-          if Arel::Nodes::Equality === node
-            node
-          else
-            wrap_sql_literal(node)
+        def predicates_with_wrapped_sql_literals
+          non_empty_predicates.map do |node|
+            case node
+            when Arel::Nodes::SqlLiteral, ::String
+              wrap_sql_literal(node)
+            else node
+            end
           end
         end
-      end
 
-      ARRAY_WITH_EMPTY_STRING = ['']
-      def non_empty_predicates
-        predicates - ARRAY_WITH_EMPTY_STRING
-      end
+        ARRAY_WITH_EMPTY_STRING = [""]
+        def non_empty_predicates
+          predicates - ARRAY_WITH_EMPTY_STRING
+        end
 
-      def wrap_sql_literal(node)
-        if ::String === node
-          node = Arel.sql(node)
+        def wrap_sql_literal(node)
+          if ::String === node
+            node = Arel.sql(node)
+          end
+          Arel::Nodes::Grouping.new(node)
+        end
+
+        def extract_node_value(node)
+          case node
+          when Array
+            node.map { |v| extract_node_value(v) }
+          when Arel::Nodes::Casted, Arel::Nodes::Quoted
+            node.val
+          when Arel::Nodes::BindParam
+            value = node.value
+            if value.respond_to?(:value_before_type_cast)
+              value.value_before_type_cast
+            else
+              value
+            end
+          end
         end
-        Arel::Nodes::Grouping.new(node)
-      end
     end
   end
 end
diff --git a/activerecord/lib/active_record/relation/where_clause_factory.rb b/activerecord/lib/active_record/relation/where_clause_factory.rb
index dbf172a577..4ae94f4bfe 100644
--- a/activerecord/lib/active_record/relation/where_clause_factory.rb
+++ b/activerecord/lib/active_record/relation/where_clause_factory.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActiveRecord
   class Relation
     class WhereClauseFactory # :nodoc:
@@ -7,32 +9,27 @@ module ActiveRecord
       end
 
       def build(opts, other)
-        binds = []
-
         case opts
         when String, Array
-          parts = [klass.send(:sanitize_sql, other.empty? ? opts : ([opts] + other))]
+          parts = [klass.sanitize_sql(other.empty? ? opts : ([opts] + other))]
         when Hash
           attributes = predicate_builder.resolve_column_aliases(opts)
           attributes = klass.send(:expand_hash_conditions_for_aggregates, attributes)
           attributes.stringify_keys!
 
-          attributes, binds = predicate_builder.create_binds(attributes)
-
           parts = predicate_builder.build_from_hash(attributes)
         when Arel::Nodes::Node
           parts = [opts]
-          binds = other
         else
           raise ArgumentError, "Unsupported argument type: #{opts} (#{opts.class})"
         end
 
-        WhereClause.new(parts, binds)
+        WhereClause.new(parts)
       end
 
       protected
 
-      attr_reader :klass, :predicate_builder
+        attr_reader :klass, :predicate_builder
     end
   end
 end
diff --git a/activerecord/lib/active_record/result.rb b/activerecord/lib/active_record/result.rb
index 8e6cd6c82f..e54e8086dd 100644
--- a/activerecord/lib/active_record/result.rb
+++ b/activerecord/lib/active_record/result.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActiveRecord
   ###
   # This class encapsulates a result returned from calling
@@ -32,8 +34,6 @@ module ActiveRecord
   class Result
     include Enumerable
 
-    IDENTITY_TYPE = Type::Value.new # :nodoc:
-
     attr_reader :columns, :rows, :column_types
 
     def initialize(columns, rows, column_types = {})
@@ -43,10 +43,15 @@ module ActiveRecord
       @column_types = column_types
     end
 
+    # Returns the number of elements in the rows array.
     def length
       @rows.length
     end
 
+    # Calls the given block once for each element in row collection, passing
+    # row as parameter.
+    #
+    # Returns an +Enumerator+ if no block is given.
     def each
       if block_given?
         hash_rows.each { |row| yield row }
@@ -55,6 +60,7 @@ module ActiveRecord
       end
     end
 
+    # Returns an array of hashes representing each row record.
     def to_hash
       hash_rows
     end
@@ -62,11 +68,12 @@ module ActiveRecord
     alias :map! :map
     alias :collect! :map
 
-    # Returns true if there are no records.
+    # Returns true if there are no records, otherwise false.
     def empty?
       rows.empty?
     end
 
+    # Returns an array of hashes representing each row record.
     def to_ary
       hash_rows
     end
@@ -75,8 +82,18 @@ module ActiveRecord
       hash_rows[idx]
     end
 
+    # Returns the first record from the rows collection.
+    # If the rows collection is empty, returns +nil+.
+    def first
+      return nil if @rows.empty?
+      Hash[@columns.zip(@rows.first)]
+    end
+
+    # Returns the last record from the rows collection.
+    # If the rows collection is empty, returns +nil+.
     def last
-      hash_rows.last
+      return nil if @rows.empty?
+      Hash[@columns.zip(@rows.last)]
     end
 
     def cast_values(type_overrides = {}) # :nodoc:
@@ -97,36 +114,36 @@ module ActiveRecord
 
     private
 
-    def column_type(name, type_overrides = {})
-      type_overrides.fetch(name) do
-        column_types.fetch(name, IDENTITY_TYPE)
+      def column_type(name, type_overrides = {})
+        type_overrides.fetch(name) do
+          column_types.fetch(name, Type.default_value)
+        end
       end
-    end
 
-    def hash_rows
-      @hash_rows ||=
-        begin
-          # We freeze the strings to prevent them getting duped when
-          # used as keys in ActiveRecord::Base's @attributes hash
-          columns = @columns.map { |c| c.dup.freeze }
-          @rows.map { |row|
-            # In the past we used Hash[columns.zip(row)]
-            #  though elegant, the verbose way is much more efficient
-            #  both time and memory wise cause it avoids a big array allocation
-            #  this method is called a lot and needs to be micro optimised
-            hash = {}
-
-            index = 0
-            length = columns.length
-
-            while index < length
-              hash[columns[index]] = row[index]
-              index += 1
-            end
-
-            hash
-          }
-        end
-    end
+      def hash_rows
+        @hash_rows ||=
+          begin
+            # We freeze the strings to prevent them getting duped when
+            # used as keys in ActiveRecord::Base's @attributes hash
+            columns = @columns.map { |c| c.dup.freeze }
+            @rows.map { |row|
+              # In the past we used Hash[columns.zip(row)]
+              #  though elegant, the verbose way is much more efficient
+              #  both time and memory wise cause it avoids a big array allocation
+              #  this method is called a lot and needs to be micro optimised
+              hash = {}
+
+              index = 0
+              length = columns.length
+
+              while index < length
+                hash[columns[index]] = row[index]
+                index += 1
+              end
+
+              hash
+            }
+          end
+      end
   end
 end
diff --git a/activerecord/lib/active_record/runtime_registry.rb b/activerecord/lib/active_record/runtime_registry.rb
index 56e88bc661..4975cb8967 100644
--- a/activerecord/lib/active_record/runtime_registry.rb
+++ b/activerecord/lib/active_record/runtime_registry.rb
@@ -1,4 +1,6 @@
-require 'active_support/per_thread_registry'
+# frozen_string_literal: true
+
+require "active_support/per_thread_registry"
 
 module ActiveRecord
   # This is a thread locals registry for Active Record. For example:
@@ -12,9 +14,9 @@ module ActiveRecord
   class RuntimeRegistry # :nodoc:
     extend ActiveSupport::PerThreadRegistry
 
-    attr_accessor :connection_handler, :sql_runtime, :connection_id
+    attr_accessor :connection_handler, :sql_runtime
 
-    [:connection_handler, :sql_runtime, :connection_id].each do |val|
+    [:connection_handler, :sql_runtime].each do |val|
       class_eval %{ def self.#{val}; instance.#{val}; end }, __FILE__, __LINE__
       class_eval %{ def self.#{val}=(x); instance.#{val}=x; end }, __FILE__, __LINE__
     end
diff --git a/activerecord/lib/active_record/sanitization.rb b/activerecord/lib/active_record/sanitization.rb
index a9e1fd0dad..58da106092 100644
--- a/activerecord/lib/active_record/sanitization.rb
+++ b/activerecord/lib/active_record/sanitization.rb
@@ -1,17 +1,10 @@
+# frozen_string_literal: true
+
 module ActiveRecord
   module Sanitization
     extend ActiveSupport::Concern
 
     module ClassMethods
-      # Used to sanitize objects before they're used in an SQL SELECT statement.
-      # Delegates to {connection.quote}[rdoc-ref:ConnectionAdapters::Quoting#quote].
-      def sanitize(object) # :nodoc:
-        connection.quote(object)
-      end
-      alias_method :quote_value, :sanitize
-
-      protected
-
       # Accepts an array or string of SQL conditions and sanitizes
       # them into a valid SQL fragment for a WHERE clause.
       #
@@ -34,8 +27,7 @@ module ActiveRecord
         else        condition
         end
       end
-      alias_method :sanitize_sql, :sanitize_sql_for_conditions
-      alias_method :sanitize_conditions, :sanitize_sql
+      alias :sanitize_sql :sanitize_sql_for_conditions
 
       # Accepts an array, hash, or string of SQL conditions and sanitizes
       # them into a valid SQL fragment for a SET clause.
@@ -46,12 +38,12 @@ module ActiveRecord
       #   sanitize_sql_for_assignment(["name=:name and group_id=:group_id", name: nil, group_id: 4])
       #   # => "name=NULL and group_id=4"
       #
-      #   Post.send(:sanitize_sql_for_assignment, { name: nil, group_id: 4 })
+      #   Post.sanitize_sql_for_assignment({ name: nil, group_id: 4 })
       #   # => "`posts`.`name` = NULL, `posts`.`group_id` = 4"
       #
       #   sanitize_sql_for_assignment("name=NULL and group_id='4'")
       #   # => "name=NULL and group_id='4'"
-      def sanitize_sql_for_assignment(assignments, default_table_name = self.table_name)
+      def sanitize_sql_for_assignment(assignments, default_table_name = table_name)
         case assignments
         when Array; sanitize_sql_array(assignments)
         when Hash;  sanitize_sql_hash_for_assignment(assignments, default_table_name)
@@ -68,47 +60,23 @@ module ActiveRecord
       #   sanitize_sql_for_order("id ASC")
       #   # => "id ASC"
       def sanitize_sql_for_order(condition)
-        if condition.is_a?(Array) && condition.first.to_s.include?('?')
-          sanitize_sql_array(condition)
+        if condition.is_a?(Array) && condition.first.to_s.include?("?")
+          enforce_raw_sql_whitelist([condition.first],
+            whitelist: AttributeMethods::ClassMethods::COLUMN_NAME_ORDER_WHITELIST
+          )
+
+          # Ensure we aren't dealing with a subclass of String that might
+          # override methods we use (eg. Arel::Nodes::SqlLiteral).
+          if condition.first.kind_of?(String) && !condition.first.instance_of?(String)
+            condition = [String.new(condition.first), *condition[1..-1]]
+          end
+
+          Arel.sql(sanitize_sql_array(condition))
         else
           condition
         end
       end
 
-      # Accepts a hash of SQL conditions and replaces those attributes
-      # that correspond to a {#composed_of}[rdoc-ref:Aggregations::ClassMethods#composed_of]
-      # relationship with their expanded aggregate attribute values.
-      #
-      # Given:
-      #
-      #   class Person < ActiveRecord::Base
-      #     composed_of :address, class_name: "Address",
-      #       mapping: [%w(address_street street), %w(address_city city)]
-      #   end
-      #
-      # Then:
-      #
-      #   { address: Address.new("813 abc st.", "chicago") }
-      #   # => { address_street: "813 abc st.", address_city: "chicago" }
-      def expand_hash_conditions_for_aggregates(attrs)
-        expanded_attrs = {}
-        attrs.each do |attr, value|
-          if aggregation = reflect_on_aggregation(attr.to_sym)
-            mapping = aggregation.mapping
-            mapping.each do |field_attr, aggregate_attr|
-              if mapping.size == 1 && !value.respond_to?(aggregate_attr)
-                expanded_attrs[field_attr] = value
-              else
-                expanded_attrs[field_attr] = value.send(aggregate_attr)
-              end
-            end
-          else
-            expanded_attrs[attr] = value
-          end
-        end
-        expanded_attrs
-      end
-
       # Sanitizes a hash of attribute/value pairs into SQL conditions for a SET clause.
       #
       #   sanitize_sql_hash_for_assignment({ status: nil, group_id: 1 }, "posts")
@@ -116,9 +84,10 @@ module ActiveRecord
       def sanitize_sql_hash_for_assignment(attrs, table)
         c = connection
         attrs.map do |attr, value|
-          value = type_for_attribute(attr.to_s).serialize(value)
+          type = type_for_attribute(attr.to_s)
+          value = type.serialize(type.cast(value))
           "#{c.quote_table_name_for_assignment(table, attr)} = #{c.quote(value)}"
-        end.join(', ')
+        end.join(", ")
       end
 
       # Sanitizes a +string+ so that it is safe to use within an SQL
@@ -153,9 +122,9 @@ module ActiveRecord
       #   # => "name='foo''bar' and group_id='4'"
       def sanitize_sql_array(ary)
         statement, *values = ary
-        if values.first.is_a?(Hash) && statement =~ /:\w+/
+        if values.first.is_a?(Hash) && /:\w+/.match?(statement)
           replace_named_bind_variables(statement, values.first)
-        elsif statement.include?('?')
+        elsif statement.include?("?")
           replace_bind_variables(statement, values)
         elsif statement.blank?
           statement
@@ -164,57 +133,87 @@ module ActiveRecord
         end
       end
 
-      def replace_bind_variables(statement, values) # :nodoc:
-        raise_if_bind_arity_mismatch(statement, statement.count('?'), values.size)
-        bound = values.dup
-        c = connection
-        statement.gsub(/\?/) do
-          replace_bind_variable(bound.shift, c)
+      private
+        # Accepts a hash of SQL conditions and replaces those attributes
+        # that correspond to a {#composed_of}[rdoc-ref:Aggregations::ClassMethods#composed_of]
+        # relationship with their expanded aggregate attribute values.
+        #
+        # Given:
+        #
+        #   class Person < ActiveRecord::Base
+        #     composed_of :address, class_name: "Address",
+        #       mapping: [%w(address_street street), %w(address_city city)]
+        #   end
+        #
+        # Then:
+        #
+        #   { address: Address.new("813 abc st.", "chicago") }
+        #   # => { address_street: "813 abc st.", address_city: "chicago" }
+        def expand_hash_conditions_for_aggregates(attrs) # :doc:
+          expanded_attrs = {}
+          attrs.each do |attr, value|
+            if aggregation = reflect_on_aggregation(attr.to_sym)
+              mapping = aggregation.mapping
+              mapping.each do |field_attr, aggregate_attr|
+                if mapping.size == 1 && !value.respond_to?(aggregate_attr)
+                  expanded_attrs[field_attr] = value
+                else
+                  expanded_attrs[field_attr] = value.send(aggregate_attr)
+                end
+              end
+            else
+              expanded_attrs[attr] = value
+            end
+          end
+          expanded_attrs
         end
-      end
 
-      def replace_bind_variable(value, c = connection) # :nodoc:
-        if ActiveRecord::Relation === value
-          value.to_sql
-        else
-          quote_bound_value(value, c)
+        def replace_bind_variables(statement, values)
+          raise_if_bind_arity_mismatch(statement, statement.count("?"), values.size)
+          bound = values.dup
+          c = connection
+          statement.gsub(/\?/) do
+            replace_bind_variable(bound.shift, c)
+          end
         end
-      end
 
-      def replace_named_bind_variables(statement, bind_vars) # :nodoc:
-        statement.gsub(/(:?):([a-zA-Z]\w*)/) do |match|
-          if $1 == ':' # skip postgresql casts
-            match # return the whole match
-          elsif bind_vars.include?(match = $2.to_sym)
-            replace_bind_variable(bind_vars[match])
+        def replace_bind_variable(value, c = connection)
+          if ActiveRecord::Relation === value
+            value.to_sql
           else
-            raise PreparedStatementInvalid, "missing value for :#{match} in #{statement}"
+            quote_bound_value(value, c)
           end
         end
-      end
 
-      def quote_bound_value(value, c = connection) # :nodoc:
-        if value.respond_to?(:map) && !value.acts_like?(:string)
-          if value.respond_to?(:empty?) && value.empty?
-            c.quote(nil)
-          else
-            value.map { |v| c.quote(v) }.join(',')
+        def replace_named_bind_variables(statement, bind_vars)
+          statement.gsub(/(:?):([a-zA-Z]\w*)/) do |match|
+            if $1 == ":" # skip postgresql casts
+              match # return the whole match
+            elsif bind_vars.include?(match = $2.to_sym)
+              replace_bind_variable(bind_vars[match])
+            else
+              raise PreparedStatementInvalid, "missing value for :#{match} in #{statement}"
+            end
           end
-        else
-          c.quote(value)
         end
-      end
 
-      def raise_if_bind_arity_mismatch(statement, expected, provided) # :nodoc:
-        unless expected == provided
-          raise PreparedStatementInvalid, "wrong number of bind variables (#{provided} for #{expected}) in: #{statement}"
+        def quote_bound_value(value, c = connection)
+          if value.respond_to?(:map) && !value.acts_like?(:string)
+            if value.respond_to?(:empty?) && value.empty?
+              c.quote(nil)
+            else
+              value.map { |v| c.quote(v) }.join(",")
+            end
+          else
+            c.quote(value)
+          end
         end
-      end
-    end
 
-    # TODO: Deprecate this
-    def quoted_id # :nodoc:
-      self.class.quote_value(@attributes[self.class.primary_key].value_for_database)
+        def raise_if_bind_arity_mismatch(statement, expected, provided)
+          unless expected == provided
+            raise PreparedStatementInvalid, "wrong number of bind variables (#{provided} for #{expected}) in: #{statement}"
+          end
+        end
     end
   end
 end
diff --git a/activerecord/lib/active_record/schema.rb b/activerecord/lib/active_record/schema.rb
index 784a02d2c3..1e121f2a09 100644
--- a/activerecord/lib/active_record/schema.rb
+++ b/activerecord/lib/active_record/schema.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActiveRecord
   # = Active Record \Schema
   #
@@ -37,10 +39,10 @@ module ActiveRecord
     # The +info+ hash is optional, and if given is used to define metadata
     # about the current schema (currently, only the schema's version):
     #
-    #   ActiveRecord::Schema.define(version: 20380119000001) do
+    #   ActiveRecord::Schema.define(version: 2038_01_19_000001) do
     #     ...
     #   end
-    def self.define(info={}, &block)
+    def self.define(info = {}, &block)
       new.define(info, &block)
     end
 
@@ -48,7 +50,7 @@ module ActiveRecord
       instance_eval(&block)
 
       if info[:version].present?
-        initialize_schema_migrations_table
+        ActiveRecord::SchemaMigration.create_table
         connection.assume_migrated_upto_version(info[:version], migrations_paths)
       end
 
@@ -61,7 +63,7 @@ module ActiveRecord
       #
       #   ActiveRecord::Schema.new.migrations_paths
       #   # => ["db/migrate"] # Rails migration path by default.
-      def migrations_paths # :nodoc:
+      def migrations_paths
         ActiveRecord::Migrator.migrations_paths
       end
   end
diff --git a/activerecord/lib/active_record/schema_dumper.rb b/activerecord/lib/active_record/schema_dumper.rb
index d769376d1a..16ccba6b6c 100644
--- a/activerecord/lib/active_record/schema_dumper.rb
+++ b/activerecord/lib/active_record/schema_dumper.rb
@@ -1,4 +1,6 @@
-require 'stringio'
+# frozen_string_literal: true
+
+require "stringio"
 
 module ActiveRecord
   # = Active Record Schema Dumper
@@ -11,14 +13,13 @@ module ActiveRecord
     ##
     # :singleton-method:
     # A list of tables which should not be dumped to the schema.
-    # Acceptable values are strings as well as regexp.
-    # This setting is only used if ActiveRecord::Base.schema_format == :ruby
-    cattr_accessor :ignore_tables
-    @@ignore_tables = []
+    # Acceptable values are strings as well as regexp if ActiveRecord::Base.schema_format == :ruby.
+    # Only strings are accepted if ActiveRecord::Base.schema_format == :sql.
+    cattr_accessor :ignore_tables, default: []
 
     class << self
-      def dump(connection=ActiveRecord::Base.connection, stream=STDOUT, config = ActiveRecord::Base)
-        new(connection, generate_options(config)).dump(stream)
+      def dump(connection = ActiveRecord::Base.connection, stream = STDOUT, config = ActiveRecord::Base)
+        connection.create_schema_dumper(generate_options(config)).dump(stream)
         stream
       end
 
@@ -47,9 +48,18 @@ module ActiveRecord
         @options = options
       end
 
-      def header(stream)
-        define_params = @version ? "version: #{@version}" : ""
+      # turns 20170404131909 into "2017_04_04_131909"
+      def formatted_version
+        stringified = @version.to_s
+        return stringified unless stringified.length == 14
+        stringified.insert(4, "_").insert(7, "_").insert(10, "_")
+      end
+
+      def define_params
+        @version ? "version: #{formatted_version}" : ""
+      end
 
+      def header(stream)
         stream.puts <<HEADER
 # This file is auto-generated from the current state of the database. Instead
 # of editing this file, please use the migrations feature of Active Record to
@@ -72,20 +82,12 @@ HEADER
         stream.puts "end"
       end
 
+      # extensions are only supported by PostgreSQL
       def extensions(stream)
-        return unless @connection.supports_extensions?
-        extensions = @connection.extensions
-        if extensions.any?
-          stream.puts "  # These are extensions that must be enabled in order to support this database"
-          extensions.each do |extension|
-            stream.puts "  enable_extension #{extension.inspect}"
-          end
-          stream.puts
-        end
       end
 
       def tables(stream)
-        sorted_tables = @connection.data_sources.sort - @connection.views
+        sorted_tables = @connection.tables.sort
 
         sorted_tables.each do |table_name|
           table(table_name, stream) unless ignored?(table_name)
@@ -105,73 +107,38 @@ HEADER
           tbl = StringIO.new
 
           # first dump primary key column
-          if @connection.respond_to?(:primary_keys)
-            pk = @connection.primary_keys(table)
-            pk = pk.first unless pk.size > 1
-          else
-            pk = @connection.primary_key(table)
-          end
+          pk = @connection.primary_key(table)
 
           tbl.print "  create_table #{remove_prefix_and_suffix(table).inspect}"
 
           case pk
           when String
-            tbl.print ", primary_key: #{pk.inspect}" unless pk == 'id'
+            tbl.print ", primary_key: #{pk.inspect}" unless pk == "id"
             pkcol = columns.detect { |c| c.name == pk }
-            pkcolspec = @connection.column_spec_for_primary_key(pkcol)
+            pkcolspec = column_spec_for_primary_key(pkcol)
             if pkcolspec.present?
-              pkcolspec.each do |key, value|
-                tbl.print ", #{key}: #{value}"
-              end
+              tbl.print ", #{format_colspec(pkcolspec)}"
             end
           when Array
             tbl.print ", primary_key: #{pk.inspect}"
           else
             tbl.print ", id: false"
           end
-          tbl.print ", force: :cascade"
 
           table_options = @connection.table_options(table)
-          tbl.print ", options: #{table_options.inspect}" unless table_options.blank?
-
-          if comment = @connection.table_comment(table).presence
-            tbl.print ", comment: #{comment.inspect}"
+          if table_options.present?
+            tbl.print ", #{format_options(table_options)}"
           end
 
-          tbl.puts " do |t|"
+          tbl.puts ", force: :cascade do |t|"
 
           # then dump all non-primary key columns
-          column_specs = columns.map do |column|
+          columns.each do |column|
             raise StandardError, "Unknown type '#{column.sql_type}' for column '#{column.name}'" unless @connection.valid_type?(column.type)
             next if column.name == pk
-            @connection.column_spec(column)
-          end.compact
-
-          # find all migration keys used in this table
-          keys = @connection.migration_keys
-
-          # figure out the lengths for each column based on above keys
-          lengths = keys.map { |key|
-            column_specs.map { |spec|
-              spec[key] ? spec[key].length + 2 : 0
-            }.max
-          }
-
-          # the string we're going to sprintf our values against, with standardized column widths
-          format_string = lengths.map{ |len| "%-#{len}s" }
-
-          # find the max length for the 'type' column, which is special
-          type_length = column_specs.map{ |column| column[:type].length }.max
-
-          # add column type definition to our format string
-          format_string.unshift "    t.%-#{type_length}s "
-
-          format_string *= ''
-
-          column_specs.each do |colspec|
-            values = keys.zip(lengths).map{ |key, len| colspec.key?(key) ? colspec[key] + ", " : " " * len }
-            values.unshift colspec[:type]
-            tbl.print((format_string % values).gsub(/,\s*$/, ''))
+            type, colspec = column_spec(column)
+            tbl.print "    t.#{type} #{column.name.inspect}"
+            tbl.print ", #{format_colspec(colspec)}" if colspec.present?
             tbl.puts
           end
 
@@ -187,8 +154,6 @@ HEADER
           stream.puts "#   #{e.message}"
           stream.puts
         end
-
-        stream
       end
 
       # Keep it for indexing materialized views
@@ -196,7 +161,7 @@ HEADER
         if (indexes = @connection.indexes(table)).any?
           add_index_statements = indexes.map do |index|
             table_name = remove_prefix_and_suffix(index.table).inspect
-            "  add_index #{([table_name]+index_parts(index)).join(', ')}"
+            "  add_index #{([table_name] + index_parts(index)).join(', ')}"
           end
 
           stream.puts add_index_statements.sort.join("\n")
@@ -218,15 +183,12 @@ HEADER
           index.columns.inspect,
           "name: #{index.name.inspect}",
         ]
-        index_parts << 'unique: true' if index.unique
-
-        index_lengths = (index.lengths || []).compact
-        index_parts << "length: #{Hash[index.columns.zip(index.lengths)].inspect}" if index_lengths.any?
-
-        index_orders = index.orders || {}
-        index_parts << "order: #{index.orders.inspect}" if index_orders.any?
+        index_parts << "unique: true" if index.unique
+        index_parts << "length: #{format_index_parts(index.lengths)}" if index.lengths.present?
+        index_parts << "order: #{format_index_parts(index.orders)}" if index.orders.present?
+        index_parts << "opclass: #{format_index_parts(index.opclasses)}" if index.opclasses.present?
         index_parts << "where: #{index.where.inspect}" if index.where
-        index_parts << "using: #{index.using.inspect}" if index.using
+        index_parts << "using: #{index.using.inspect}" if !@connection.default_index_type?(index)
         index_parts << "type: #{index.type.inspect}" if index.type
         index_parts << "comment: #{index.comment.inspect}" if index.comment
         index_parts
@@ -262,8 +224,26 @@ HEADER
         end
       end
 
+      def format_colspec(colspec)
+        colspec.map { |key, value| "#{key}: #{value}" }.join(", ")
+      end
+
+      def format_options(options)
+        options.map { |key, value| "#{key}: #{value.inspect}" }.join(", ")
+      end
+
+      def format_index_parts(options)
+        if options.is_a?(Hash)
+          "{ #{format_options(options)} }"
+        else
+          options.inspect
+        end
+      end
+
       def remove_prefix_and_suffix(table)
-        table.gsub(/^(#{@options[:table_name_prefix]})(.+)(#{@options[:table_name_suffix]})$/,  "\\2")
+        prefix = Regexp.escape(@options[:table_name_prefix].to_s)
+        suffix = Regexp.escape(@options[:table_name_suffix].to_s)
+        table.sub(/\A#{prefix}(.+)#{suffix}\z/, "\\1")
       end
 
       def ignored?(table_name)
diff --git a/activerecord/lib/active_record/schema_migration.rb b/activerecord/lib/active_record/schema_migration.rb
index b6cb233e03..f2d8b038fa 100644
--- a/activerecord/lib/active_record/schema_migration.rb
+++ b/activerecord/lib/active_record/schema_migration.rb
@@ -1,5 +1,7 @@
-require 'active_record/scoping/default'
-require 'active_record/scoping/named'
+# frozen_string_literal: true
+
+require "active_record/scoping/default"
+require "active_record/scoping/named"
 
 module ActiveRecord
   # This class is used to create a table that keeps track of which migrations
@@ -17,7 +19,7 @@ module ActiveRecord
       end
 
       def table_exists?
-        ActiveSupport::Deprecation.silence { connection.table_exists?(table_name) }
+        connection.table_exists?(table_name)
       end
 
       def create_table
@@ -39,7 +41,11 @@ module ActiveRecord
       end
 
       def normalized_versions
-        pluck(:version).map { |v| normalize_migration_number v }
+        all_versions.map { |v| normalize_migration_number v }
+      end
+
+      def all_versions
+        order(:version).pluck(:version)
       end
     end
 
diff --git a/activerecord/lib/active_record/scoping.rb b/activerecord/lib/active_record/scoping.rb
index 7794af8ca4..01ac56570a 100644
--- a/activerecord/lib/active_record/scoping.rb
+++ b/activerecord/lib/active_record/scoping.rb
@@ -1,4 +1,6 @@
-require 'active_support/per_thread_registry'
+# frozen_string_literal: true
+
+require "active_support/per_thread_registry"
 
 module ActiveRecord
   module Scoping
@@ -9,23 +11,23 @@ module ActiveRecord
       include Named
     end
 
-    module ClassMethods
-      def current_scope #:nodoc:
-        ScopeRegistry.value_for(:current_scope, self)
+    module ClassMethods # :nodoc:
+      def current_scope(skip_inherited_scope = false)
+        ScopeRegistry.value_for(:current_scope, self, skip_inherited_scope)
       end
 
-      def current_scope=(scope) #:nodoc:
+      def current_scope=(scope)
         ScopeRegistry.set_value_for(:current_scope, self, scope)
       end
 
       # Collects attributes from scopes that should be applied when creating
       # an AR instance for the particular class this is called on.
-      def scope_attributes # :nodoc:
+      def scope_attributes
         all.scope_for_create
       end
 
       # Are there attributes associated with this scope?
-      def scope_attributes? # :nodoc:
+      def scope_attributes?
         current_scope
       end
     end
@@ -33,9 +35,8 @@ module ActiveRecord
     def populate_with_current_scope_attributes # :nodoc:
       return unless self.class.scope_attributes?
 
-      self.class.scope_attributes.each do |att,value|
-        send("#{att}=", value) if respond_to?("#{att}=")
-      end
+      attributes = self.class.scope_attributes
+      _assign_attributes(attributes) if attributes.any?
     end
 
     def initialize_internals_callback # :nodoc:
@@ -75,8 +76,9 @@ module ActiveRecord
       end
 
       # Obtains the value for a given +scope_type+ and +model+.
-      def value_for(scope_type, model)
+      def value_for(scope_type, model, skip_inherited_scope = false)
         raise_invalid_scope_type!(scope_type)
+        return @registry[scope_type][model.name] if skip_inherited_scope
         klass = model
         base = model.base_class
         while klass <= base
@@ -94,11 +96,11 @@ module ActiveRecord
 
       private
 
-      def raise_invalid_scope_type!(scope_type)
-        if !VALID_SCOPE_TYPES.include?(scope_type)
-          raise ArgumentError, "Invalid scope type '#{scope_type}' sent to the registry. Scope types must be included in VALID_SCOPE_TYPES"
+        def raise_invalid_scope_type!(scope_type)
+          if !VALID_SCOPE_TYPES.include?(scope_type)
+            raise ArgumentError, "Invalid scope type '#{scope_type}' sent to the registry. Scope types must be included in VALID_SCOPE_TYPES"
+          end
         end
-      end
     end
   end
 end
diff --git a/activerecord/lib/active_record/scoping/default.rb b/activerecord/lib/active_record/scoping/default.rb
index 9eab59ac78..8c612df27a 100644
--- a/activerecord/lib/active_record/scoping/default.rb
+++ b/activerecord/lib/active_record/scoping/default.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActiveRecord
   module Scoping
     module Default
@@ -5,11 +7,8 @@ module ActiveRecord
 
       included do
         # Stores the default scope for the class.
-        class_attribute :default_scopes, instance_writer: false, instance_predicate: false
-        class_attribute :default_scope_override, instance_writer: false, instance_predicate: false
-
-        self.default_scopes = []
-        self.default_scope_override = nil
+        class_attribute :default_scopes, instance_writer: false, instance_predicate: false, default: []
+        class_attribute :default_scope_override, instance_writer: false, instance_predicate: false, default: nil
       end
 
       module ClassMethods
@@ -44,105 +43,109 @@ module ActiveRecord
           self.current_scope = nil
         end
 
-        protected
+        private
+
+          # Use this macro in your model to set a default scope for all operations on
+          # the model.
+          #
+          #   class Article < ActiveRecord::Base
+          #     default_scope { where(published: true) }
+          #   end
+          #
+          #   Article.all # => SELECT * FROM articles WHERE published = true
+          #
+          # The #default_scope is also applied while creating/building a record.
+          # It is not applied while updating a record.
+          #
+          #   Article.new.published    # => true
+          #   Article.create.published # => true
+          #
+          # (You can also pass any object which responds to +call+ to the
+          # +default_scope+ macro, and it will be called when building the
+          # default scope.)
+          #
+          # If you use multiple #default_scope declarations in your model then
+          # they will be merged together:
+          #
+          #   class Article < ActiveRecord::Base
+          #     default_scope { where(published: true) }
+          #     default_scope { where(rating: 'G') }
+          #   end
+          #
+          #   Article.all # => SELECT * FROM articles WHERE published = true AND rating = 'G'
+          #
+          # This is also the case with inheritance and module includes where the
+          # parent or module defines a #default_scope and the child or including
+          # class defines a second one.
+          #
+          # If you need to do more complex things with a default scope, you can
+          # alternatively define it as a class method:
+          #
+          #   class Article < ActiveRecord::Base
+          #     def self.default_scope
+          #       # Should return a scope, you can call 'super' here etc.
+          #     end
+          #   end
+          def default_scope(scope = nil) # :doc:
+            scope = Proc.new if block_given?
+
+            if scope.is_a?(Relation) || !scope.respond_to?(:call)
+              raise ArgumentError,
+                "Support for calling #default_scope without a block is removed. For example instead " \
+                "of `default_scope where(color: 'red')`, please use " \
+                "`default_scope { where(color: 'red') }`. (Alternatively you can just redefine " \
+                "self.default_scope.)"
+            end
 
-        # Use this macro in your model to set a default scope for all operations on
-        # the model.
-        #
-        #   class Article < ActiveRecord::Base
-        #     default_scope { where(published: true) }
-        #   end
-        #
-        #   Article.all # => SELECT * FROM articles WHERE published = true
-        #
-        # The #default_scope is also applied while creating/building a record.
-        # It is not applied while updating a record.
-        #
-        #   Article.new.published    # => true
-        #   Article.create.published # => true
-        #
-        # (You can also pass any object which responds to +call+ to the
-        # +default_scope+ macro, and it will be called when building the
-        # default scope.)
-        #
-        # If you use multiple #default_scope declarations in your model then
-        # they will be merged together:
-        #
-        #   class Article < ActiveRecord::Base
-        #     default_scope { where(published: true) }
-        #     default_scope { where(rating: 'G') }
-        #   end
-        #
-        #   Article.all # => SELECT * FROM articles WHERE published = true AND rating = 'G'
-        #
-        # This is also the case with inheritance and module includes where the
-        # parent or module defines a #default_scope and the child or including
-        # class defines a second one.
-        #
-        # If you need to do more complex things with a default scope, you can
-        # alternatively define it as a class method:
-        #
-        #   class Article < ActiveRecord::Base
-        #     def self.default_scope
-        #       # Should return a scope, you can call 'super' here etc.
-        #     end
-        #   end
-        def default_scope(scope = nil)
-          scope = Proc.new if block_given?
-
-          if scope.is_a?(Relation) || !scope.respond_to?(:call)
-            raise ArgumentError,
-              "Support for calling #default_scope without a block is removed. For example instead " \
-              "of `default_scope where(color: 'red')`, please use " \
-              "`default_scope { where(color: 'red') }`. (Alternatively you can just redefine " \
-              "self.default_scope.)"
+            self.default_scopes += [scope]
           end
 
-          self.default_scopes += [scope]
-        end
-
-        def build_default_scope(base_rel = nil) # :nodoc:
-          return if abstract_class?
+          def build_default_scope(base_rel = nil)
+            return if abstract_class?
 
-          if self.default_scope_override.nil?
-            self.default_scope_override = !Base.is_a?(method(:default_scope).owner)
-          end
+            if default_scope_override.nil?
+              self.default_scope_override = !Base.is_a?(method(:default_scope).owner)
+            end
 
-          if self.default_scope_override
-            # The user has defined their own default scope method, so call that
-            evaluate_default_scope { default_scope }
-          elsif default_scopes.any?
-            base_rel ||= relation
-            evaluate_default_scope do
-              default_scopes.inject(base_rel) do |default_scope, scope|
-                scope = scope.respond_to?(:to_proc) ? scope : scope.method(:call)
-                default_scope.merge(base_rel.instance_exec(&scope))
+            if default_scope_override
+              # The user has defined their own default scope method, so call that
+              evaluate_default_scope do
+                if scope = default_scope
+                  (base_rel ||= relation).merge!(scope)
+                end
+              end
+            elsif default_scopes.any?
+              base_rel ||= relation
+              evaluate_default_scope do
+                default_scopes.inject(base_rel) do |default_scope, scope|
+                  scope = scope.respond_to?(:to_proc) ? scope : scope.method(:call)
+                  default_scope.merge!(base_rel.instance_exec(&scope))
+                end
               end
             end
           end
-        end
 
-        def ignore_default_scope? # :nodoc:
-          ScopeRegistry.value_for(:ignore_default_scope, base_class)
-        end
+          def ignore_default_scope?
+            ScopeRegistry.value_for(:ignore_default_scope, base_class)
+          end
 
-        def ignore_default_scope=(ignore) # :nodoc:
-          ScopeRegistry.set_value_for(:ignore_default_scope, base_class, ignore)
-        end
+          def ignore_default_scope=(ignore)
+            ScopeRegistry.set_value_for(:ignore_default_scope, base_class, ignore)
+          end
 
-        # The ignore_default_scope flag is used to prevent an infinite recursion
-        # situation where a default scope references a scope which has a default
-        # scope which references a scope...
-        def evaluate_default_scope # :nodoc:
-          return if ignore_default_scope?
-
-          begin
-            self.ignore_default_scope = true
-            yield
-          ensure
-            self.ignore_default_scope = false
+          # The ignore_default_scope flag is used to prevent an infinite recursion
+          # situation where a default scope references a scope which has a default
+          # scope which references a scope...
+          def evaluate_default_scope
+            return if ignore_default_scope?
+
+            begin
+              self.ignore_default_scope = true
+              yield
+            ensure
+              self.ignore_default_scope = false
+            end
           end
-        end
       end
     end
   end
diff --git a/activerecord/lib/active_record/scoping/named.rb b/activerecord/lib/active_record/scoping/named.rb
index 5395bd6076..752655aa05 100644
--- a/activerecord/lib/active_record/scoping/named.rb
+++ b/activerecord/lib/active_record/scoping/named.rb
@@ -1,6 +1,8 @@
-require 'active_support/core_ext/array'
-require 'active_support/core_ext/hash/except'
-require 'active_support/core_ext/kernel/singleton_class'
+# frozen_string_literal: true
+
+require "active_support/core_ext/array"
+require "active_support/core_ext/hash/except"
+require "active_support/core_ext/kernel/singleton_class"
 
 module ActiveRecord
   # = Active Record \Named \Scopes
@@ -22,27 +24,45 @@ module ActiveRecord
         # You can define a scope that applies to all finders using
         # {default_scope}[rdoc-ref:Scoping::Default::ClassMethods#default_scope].
         def all
+          current_scope = self.current_scope
+
           if current_scope
-            current_scope.clone
+            if self == current_scope.klass
+              current_scope.clone
+            else
+              relation.merge!(current_scope)
+            end
           else
             default_scoped
           end
         end
 
-        def default_scoped # :nodoc:
-          scope = build_default_scope
+        def scope_for_association(scope = relation) # :nodoc:
+          current_scope = self.current_scope
+
+          if current_scope && current_scope.empty_scope?
+            scope
+          else
+            default_scoped(scope)
+          end
+        end
+
+        def default_scoped(scope = relation) # :nodoc:
+          build_default_scope(scope) || scope
+        end
 
-          if scope
-            relation.spawn.merge!(scope)
+        def default_extensions # :nodoc:
+          if scope = current_scope || build_default_scope
+            scope.extensions
           else
-            relation
+            []
           end
         end
 
         # Adds a class method for retrieving and querying objects.
         # The method is intended to return an ActiveRecord::Relation
         # object, which is composable with other scopes.
-        # If it returns nil or false, an
+        # If it returns +nil+ or +false+, an
         # {all}[rdoc-ref:Scoping::Named::ClassMethods#all] scope is returned instead.
         #
         # A \scope represents a narrowing of a database query, such as
@@ -142,7 +162,7 @@ module ActiveRecord
         #   Article.featured.titles
         def scope(name, body, &block)
           unless body.respond_to?(:call)
-            raise ArgumentError, 'The scope body needs to be callable.'
+            raise ArgumentError, "The scope body needs to be callable."
           end
 
           if dangerous_class_method?(name)
@@ -151,34 +171,40 @@ module ActiveRecord
               "a class method with the same name."
           end
 
+          if method_defined_within?(name, Relation)
+            raise ArgumentError, "You tried to define a scope named \"#{name}\" " \
+              "on the model \"#{self.name}\", but ActiveRecord::Relation already defined " \
+              "an instance method with the same name."
+          end
+
           valid_scope_name?(name)
           extension = Module.new(&block) if block
 
           if body.respond_to?(:to_proc)
             singleton_class.send(:define_method, name) do |*args|
-              scope = all.scoping { instance_exec(*args, &body) }
+              scope = all
+              scope = scope.instance_exec(*args, &body) || scope
               scope = scope.extending(extension) if extension
-
-              scope || all
+              scope
             end
           else
             singleton_class.send(:define_method, name) do |*args|
-              scope = all.scoping { body.call(*args) }
+              scope = all
+              scope = scope.scoping { body.call(*args) || scope }
               scope = scope.extending(extension) if extension
-
-              scope || all
+              scope
             end
           end
         end
 
-      protected
+        private
 
-        def valid_scope_name?(name)
-          if respond_to?(name, true)
-            logger.warn "Creating scope :#{name}. " \
-                        "Overwriting existing method #{self.name}.#{name}."
+          def valid_scope_name?(name)
+            if respond_to?(name, true) && logger
+              logger.warn "Creating scope :#{name}. " \
+                "Overwriting existing method #{self.name}.#{name}."
+            end
           end
-        end
       end
     end
   end
diff --git a/activerecord/lib/active_record/secure_token.rb b/activerecord/lib/active_record/secure_token.rb
index 8abda2ac49..bcdb33901b 100644
--- a/activerecord/lib/active_record/secure_token.rb
+++ b/activerecord/lib/active_record/secure_token.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActiveRecord
   module SecureToken
     extend ActiveSupport::Concern
@@ -25,9 +27,9 @@ module ActiveRecord
       # You're encouraged to add a unique index in the database to deal with this even more unlikely scenario.
       def has_secure_token(attribute = :token)
         # Load securerandom only when has_secure_token is used.
-        require 'active_support/core_ext/securerandom'
+        require "active_support/core_ext/securerandom"
         define_method("regenerate_#{attribute}") { update! attribute => self.class.generate_unique_secure_token }
-        before_create { self.send("#{attribute}=", self.class.generate_unique_secure_token) unless self.send("#{attribute}?")}
+        before_create { send("#{attribute}=", self.class.generate_unique_secure_token) unless send("#{attribute}?") }
       end
 
       def generate_unique_secure_token
diff --git a/activerecord/lib/active_record/serialization.rb b/activerecord/lib/active_record/serialization.rb
index 5a408e7b8e..741fea43ce 100644
--- a/activerecord/lib/active_record/serialization.rb
+++ b/activerecord/lib/active_record/serialization.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActiveRecord #:nodoc:
   # = Active Record \Serialization
   module Serialization
@@ -9,7 +11,7 @@ module ActiveRecord #:nodoc:
     end
 
     def serializable_hash(options = nil)
-      options = options.try(:clone) || {}
+      options = options.try(:dup) || {}
 
       options[:except] = Array(options[:except]).map(&:to_s)
       options[:except] |= Array(self.class.inheritance_column)
diff --git a/activerecord/lib/active_record/statement_cache.rb b/activerecord/lib/active_record/statement_cache.rb
index 6c896ccea6..59acd63a0f 100644
--- a/activerecord/lib/active_record/statement_cache.rb
+++ b/activerecord/lib/active_record/statement_cache.rb
@@ -1,5 +1,6 @@
-module ActiveRecord
+# frozen_string_literal: true
 
+module ActiveRecord
   # Statement cache is used to cache a single statement in order to avoid creating the AST again.
   # Initializing the cache is done by passing the statement in the create block:
   #
@@ -8,12 +9,12 @@ module ActiveRecord
   #   end
   #
   # The cached statement is executed by using the
-  # [connection.execute]{rdoc-ref:ConnectionAdapters::DatabaseStatements#execute} method:
+  # {connection.execute}[rdoc-ref:ConnectionAdapters::DatabaseStatements#execute] method:
   #
-  #   cache.execute([], Book, Book.connection)
+  #   cache.execute([], Book.connection)
   #
   # The relation returned by the block is cached, and for each
-  # [execute]{rdoc-ref:ConnectionAdapters::DatabaseStatements#execute}
+  # {execute}[rdoc-ref:ConnectionAdapters::DatabaseStatements#execute]
   # call the cached relation gets duped. Database is queried when +to_a+ is called on the relation.
   #
   # If you want to cache the statement without the values you can use the +bind+ method of the
@@ -25,7 +26,7 @@ module ActiveRecord
   #
   # And pass the bind values as the first argument of +execute+ call.
   #
-  #   cache.execute(["my book"], Book, Book.connection)
+  #   cache.execute(["my book"], Book.connection)
   class StatementCache # :nodoc:
     class Substitute; end # :nodoc:
 
@@ -40,28 +41,27 @@ module ActiveRecord
     end
 
     class PartialQuery < Query # :nodoc:
-      def initialize values
+      def initialize(values)
         @values = values
-        @indexes = values.each_with_index.find_all { |thing,i|
+        @indexes = values.each_with_index.find_all { |thing, i|
           Arel::Nodes::BindParam === thing
         }.map(&:last)
       end
 
       def sql_for(binds, connection)
         val = @values.dup
-        binds = connection.prepare_binds_for_database(binds)
-        @indexes.each { |i| val[i] = connection.quote(binds.shift) }
+        casted_binds = binds.map(&:value_for_database)
+        @indexes.each { |i| val[i] = connection.quote(casted_binds.shift) }
         val.join
       end
     end
 
-    def self.query(visitor, ast)
-      Query.new visitor.accept(ast, Arel::Collectors::SQLString.new).value
+    def self.query(sql)
+      Query.new(sql)
     end
 
-    def self.partial_query(visitor, ast, collector)
-      collected = visitor.accept(ast, collector).value
-      PartialQuery.new collected
+    def self.partial_query(values)
+      PartialQuery.new(values)
     end
 
     class Params # :nodoc:
@@ -70,7 +70,7 @@ module ActiveRecord
 
     class BindMap # :nodoc:
       def initialize(bound_attributes)
-        @indexes   = []
+        @indexes = []
         @bound_attributes = bound_attributes
 
         bound_attributes.each_with_index do |attr, i|
@@ -82,32 +82,40 @@ module ActiveRecord
 
       def bind(values)
         bas = @bound_attributes.dup
-        @indexes.each_with_index { |offset,i| bas[offset] = bas[offset].with_cast_value(values[i]) }
+        @indexes.each_with_index { |offset, i| bas[offset] = bas[offset].with_cast_value(values[i]) }
         bas
       end
     end
 
-    attr_reader :bind_map, :query_builder
-
     def self.create(connection, block = Proc.new)
-      relation      = block.call Params.new
-      bind_map      = BindMap.new relation.bound_attributes
-      query_builder = connection.cacheable_query relation.arel
-      new query_builder, bind_map
+      relation = block.call Params.new
+      query_builder, binds = connection.cacheable_query(self, relation.arel)
+      bind_map = BindMap.new(binds)
+      new(query_builder, bind_map, relation.klass)
     end
 
-    def initialize(query_builder, bind_map)
+    def initialize(query_builder, bind_map, klass)
       @query_builder = query_builder
-      @bind_map      = bind_map
+      @bind_map = bind_map
+      @klass = klass
     end
 
-    def execute(params, klass, connection)
+    def execute(params, connection, &block)
       bind_values = bind_map.bind params
 
       sql = query_builder.sql_for bind_values, connection
 
-      klass.find_by_sql(sql, bind_values, preparable: true)
+      klass.find_by_sql(sql, bind_values, preparable: true, &block)
+    end
+
+    def self.unsupported_value?(value)
+      case value
+      when NilClass, Array, Range, Hash, Relation, Base then true
+      end
     end
-    alias :call :execute
+
+    protected
+
+      attr_reader :query_builder, :bind_map, :klass
   end
 end
diff --git a/activerecord/lib/active_record/store.rb b/activerecord/lib/active_record/store.rb
index 1b407f7702..202b82fa61 100644
--- a/activerecord/lib/active_record/store.rb
+++ b/activerecord/lib/active_record/store.rb
@@ -1,4 +1,6 @@
-require 'active_support/core_ext/hash/indifferent_access'
+# frozen_string_literal: true
+
+require "active_support/core_ext/hash/indifferent_access"
 
 module ActiveRecord
   # Store gives you a thin wrapper around serialize for the purpose of storing hashes in a single column.
@@ -78,7 +80,7 @@ module ActiveRecord
 
     module ClassMethods
       def store(store_attribute, options = {})
-        serialize store_attribute, IndifferentCoder.new(options[:coder])
+        serialize store_attribute, IndifferentCoder.new(store_attribute, options[:coder])
         store_accessor(store_attribute, options[:accessors]) if options.has_key? :accessors
       end
 
@@ -114,25 +116,24 @@ module ActiveRecord
 
       def stored_attributes
         parent = superclass.respond_to?(:stored_attributes) ? superclass.stored_attributes : {}
-        if self.local_stored_attributes
-          parent.merge!(self.local_stored_attributes) { |k, a, b| a | b }
+        if local_stored_attributes
+          parent.merge!(local_stored_attributes) { |k, a, b| a | b }
         end
         parent
       end
     end
 
-    protected
-      def read_store_attribute(store_attribute, key)
+    private
+      def read_store_attribute(store_attribute, key) # :doc:
         accessor = store_accessor_for(store_attribute)
         accessor.read(self, store_attribute, key)
       end
 
-      def write_store_attribute(store_attribute, key, value)
+      def write_store_attribute(store_attribute, key, value) # :doc:
         accessor = store_accessor_for(store_attribute)
         accessor.write(self, store_attribute, key, value)
       end
 
-    private
       def store_accessor_for(store_attribute)
         type_for_attribute(store_attribute.to_s).accessor
       end
@@ -177,34 +178,34 @@ module ActiveRecord
         end
       end
 
-    class IndifferentCoder # :nodoc:
-      def initialize(coder_or_class_name)
-        @coder =
-          if coder_or_class_name.respond_to?(:load) && coder_or_class_name.respond_to?(:dump)
-            coder_or_class_name
-          else
-            ActiveRecord::Coders::YAMLColumn.new(coder_or_class_name || Object)
-          end
-      end
+      class IndifferentCoder # :nodoc:
+        def initialize(attr_name, coder_or_class_name)
+          @coder =
+            if coder_or_class_name.respond_to?(:load) && coder_or_class_name.respond_to?(:dump)
+              coder_or_class_name
+            else
+              ActiveRecord::Coders::YAMLColumn.new(attr_name, coder_or_class_name || Object)
+            end
+        end
 
-      def dump(obj)
-        @coder.dump self.class.as_indifferent_hash(obj)
-      end
+        def dump(obj)
+          @coder.dump self.class.as_indifferent_hash(obj)
+        end
 
-      def load(yaml)
-        self.class.as_indifferent_hash(@coder.load(yaml || ''))
-      end
+        def load(yaml)
+          self.class.as_indifferent_hash(@coder.load(yaml || ""))
+        end
 
-      def self.as_indifferent_hash(obj)
-        case obj
-        when ActiveSupport::HashWithIndifferentAccess
-          obj
-        when Hash
-          obj.with_indifferent_access
-        else
-          ActiveSupport::HashWithIndifferentAccess.new
+        def self.as_indifferent_hash(obj)
+          case obj
+          when ActiveSupport::HashWithIndifferentAccess
+            obj
+          when Hash
+            obj.with_indifferent_access
+          else
+            ActiveSupport::HashWithIndifferentAccess.new
+          end
         end
       end
-    end
   end
 end
diff --git a/activerecord/lib/active_record/suppressor.rb b/activerecord/lib/active_record/suppressor.rb
index d9acb1a1dc..8cdb8e0765 100644
--- a/activerecord/lib/active_record/suppressor.rb
+++ b/activerecord/lib/active_record/suppressor.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActiveRecord
   # ActiveRecord::Suppressor prevents the receiver from being saved during
   # a given block.
diff --git a/activerecord/lib/active_record/table_metadata.rb b/activerecord/lib/active_record/table_metadata.rb
index a1326aa359..0459cbdc59 100644
--- a/activerecord/lib/active_record/table_metadata.rb
+++ b/activerecord/lib/active_record/table_metadata.rb
@@ -1,7 +1,8 @@
+# frozen_string_literal: true
+
 module ActiveRecord
   class TableMetadata # :nodoc:
-    delegate :foreign_type, :foreign_key, to: :association, prefix: true
-    delegate :association_primary_key, to: :association
+    delegate :foreign_type, :foreign_key, :join_primary_key, :join_foreign_key, to: :association, prefix: true
 
     def initialize(klass, arel_table, association = nil)
       @klass = klass
@@ -10,9 +11,7 @@ module ActiveRecord
     end
 
     def resolve_column_aliases(hash)
-      # This method is a hot spot, so for now, use Hash[] to dup the hash.
-      #   https://bugs.ruby-lang.org/issues/7166
-      new_hash = Hash[hash]
+      new_hash = hash.dup
       hash.each do |key, _|
         if (key.is_a?(Symbol)) && klass.attribute_alias?(key)
           new_hash[klass.attribute_alias(key)] = new_hash.delete(key)
@@ -33,20 +32,24 @@ module ActiveRecord
       if klass
         klass.type_for_attribute(column_name.to_s)
       else
-        Type::Value.new
+        Type.default_value
       end
     end
 
+    def has_column?(column_name)
+      klass && klass.columns_hash.key?(column_name.to_s)
+    end
+
     def associated_with?(association_name)
       klass && klass._reflect_on_association(association_name)
     end
 
     def associated_table(table_name)
-      return self if table_name == arel_table.name
-
-      association = klass._reflect_on_association(table_name) || klass._reflect_on_association(table_name.singularize)
+      association = klass._reflect_on_association(table_name) || klass._reflect_on_association(table_name.to_s.singularize)
 
-      if association && !association.polymorphic?
+      if !association && table_name == arel_table.name
+        return self
+      elsif association && !association.polymorphic?
         association_klass = association.klass
         arel_table = association_klass.arel_table.alias(table_name)
       else
@@ -62,8 +65,10 @@ module ActiveRecord
       association && association.polymorphic?
     end
 
+    # TODO Change this to private once we've dropped Ruby 2.2 support.
+    # Workaround for Ruby 2.2 "private attribute?" warning.
     protected
 
-    attr_reader :klass, :arel_table, :association
+      attr_reader :klass, :arel_table, :association
   end
 end
diff --git a/activerecord/lib/active_record/tasks/database_tasks.rb b/activerecord/lib/active_record/tasks/database_tasks.rb
index e3e665e149..4657e51e6d 100644
--- a/activerecord/lib/active_record/tasks/database_tasks.rb
+++ b/activerecord/lib/active_record/tasks/database_tasks.rb
@@ -1,4 +1,4 @@
-require 'active_support/core_ext/string/filters'
+# frozen_string_literal: true
 
 module ActiveRecord
   module Tasks # :nodoc:
@@ -35,15 +35,25 @@ module ActiveRecord
     #
     #   DatabaseTasks.create_current('production')
     module DatabaseTasks
+      ##
+      # :singleton-method:
+      # Extra flags passed to database CLI tool (mysqldump/pg_dump) when calling db:structure:dump
+      mattr_accessor :structure_dump_flags, instance_accessor: false
+
+      ##
+      # :singleton-method:
+      # Extra flags passed to database CLI tool when calling db:structure:load
+      mattr_accessor :structure_load_flags, instance_accessor: false
+
       extend self
 
       attr_writer :current_config, :db_dir, :migrations_paths, :fixtures_path, :root, :env, :seed_loader
       attr_accessor :database_configuration
 
-      LOCAL_HOSTS    = ['127.0.0.1', 'localhost']
+      LOCAL_HOSTS = ["127.0.0.1", "localhost"]
 
       def check_protected_environments!
-        unless ENV['DISABLE_DATABASE_ENVIRONMENT_CHECK']
+        unless ENV["DISABLE_DATABASE_ENVIRONMENT_CHECK"]
           current = ActiveRecord::Migrator.current_environment
           stored  = ActiveRecord::Migrator.last_stored_environment
 
@@ -63,24 +73,24 @@ module ActiveRecord
         @tasks[pattern] = task
       end
 
-      register_task(/mysql/,        ActiveRecord::Tasks::MySQLDatabaseTasks)
-      register_task(/postgresql/,   ActiveRecord::Tasks::PostgreSQLDatabaseTasks)
-      register_task(/sqlite/,       ActiveRecord::Tasks::SQLiteDatabaseTasks)
+      register_task(/mysql/,        "ActiveRecord::Tasks::MySQLDatabaseTasks")
+      register_task(/postgresql/,   "ActiveRecord::Tasks::PostgreSQLDatabaseTasks")
+      register_task(/sqlite/,       "ActiveRecord::Tasks::SQLiteDatabaseTasks")
 
       def db_dir
         @db_dir ||= Rails.application.config.paths["db"].first
       end
 
       def migrations_paths
-        @migrations_paths ||= Rails.application.paths['db/migrate'].to_a
+        @migrations_paths ||= Rails.application.paths["db/migrate"].to_a
       end
 
       def fixtures_path
-        @fixtures_path ||= if ENV['FIXTURES_PATH']
-                             File.join(root, ENV['FIXTURES_PATH'])
-                           else
-                             File.join(root, 'test', 'fixtures')
-                           end
+        @fixtures_path ||= if ENV["FIXTURES_PATH"]
+          File.join(root, ENV["FIXTURES_PATH"])
+        else
+          File.join(root, "test", "fixtures")
+        end
       end
 
       def root
@@ -96,7 +106,7 @@ module ActiveRecord
       end
 
       def current_config(options = {})
-        options.reverse_merge! :env => env
+        options.reverse_merge! env: env
         if options.has_key?(:config)
           @current_config = options[:config]
         else
@@ -106,7 +116,7 @@ module ActiveRecord
 
       def create(*arguments)
         configuration = arguments.first
-        class_for_adapter(configuration['adapter']).new(*arguments).create
+        class_for_adapter(configuration["adapter"]).new(*arguments).create
         $stdout.puts "Created database '#{configuration['database']}'"
       rescue DatabaseAlreadyExists
         $stderr.puts "Database '#{configuration['database']}' already exists"
@@ -133,7 +143,7 @@ module ActiveRecord
 
       def drop(*arguments)
         configuration = arguments.first
-        class_for_adapter(configuration['adapter']).new(*arguments).drop
+        class_for_adapter(configuration["adapter"]).new(*arguments).drop
         $stdout.puts "Dropped database '#{configuration['database']}'"
       rescue ActiveRecord::NoDatabaseError
         $stderr.puts "Database '#{configuration['database']}' does not exist"
@@ -154,11 +164,12 @@ module ActiveRecord
       end
 
       def migrate
-        verbose = ENV["VERBOSE"] ? ENV["VERBOSE"] == "true" : true
-        version = ENV["VERSION"] ? ENV["VERSION"].to_i : nil
-        scope   = ENV['SCOPE']
+        check_target_version
+
+        verbose = ENV["VERBOSE"] ? ENV["VERBOSE"] != "false" : true
+        scope = ENV["SCOPE"]
         verbose_was, Migration.verbose = Migration.verbose, verbose
-        Migrator.migrate(migrations_paths, version) do |migration|
+        Migrator.migrate(migrations_paths, target_version) do |migration|
           scope.blank? || scope == migration.scope
         end
         ActiveRecord::Base.clear_cache!
@@ -166,13 +177,23 @@ module ActiveRecord
         Migration.verbose = verbose_was
       end
 
+      def check_target_version
+        if target_version && !(Migration::MigrationFilenameRegexp.match?(ENV["VERSION"]) || /\A\d+\z/.match?(ENV["VERSION"]))
+          raise "Invalid format of target version: `VERSION=#{ENV['VERSION']}`"
+        end
+      end
+
+      def target_version
+        ENV["VERSION"].to_i if ENV["VERSION"] && !ENV["VERSION"].empty?
+      end
+
       def charset_current(environment = env)
         charset ActiveRecord::Base.configurations[environment]
       end
 
       def charset(*arguments)
         configuration = arguments.first
-        class_for_adapter(configuration['adapter']).new(*arguments).charset
+        class_for_adapter(configuration["adapter"]).new(*arguments).charset
       end
 
       def collation_current(environment = env)
@@ -181,11 +202,11 @@ module ActiveRecord
 
       def collation(*arguments)
         configuration = arguments.first
-        class_for_adapter(configuration['adapter']).new(*arguments).collation
+        class_for_adapter(configuration["adapter"]).new(*arguments).collation
       end
 
       def purge(configuration)
-        class_for_adapter(configuration['adapter']).new(configuration).purge
+        class_for_adapter(configuration["adapter"]).new(configuration).purge
       end
 
       def purge_all
@@ -204,39 +225,31 @@ module ActiveRecord
       def structure_dump(*arguments)
         configuration = arguments.first
         filename = arguments.delete_at 1
-        class_for_adapter(configuration['adapter']).new(*arguments).structure_dump(filename)
+        class_for_adapter(configuration["adapter"]).new(*arguments).structure_dump(filename, structure_dump_flags)
       end
 
       def structure_load(*arguments)
         configuration = arguments.first
         filename = arguments.delete_at 1
-        class_for_adapter(configuration['adapter']).new(*arguments).structure_load(filename)
+        class_for_adapter(configuration["adapter"]).new(*arguments).structure_load(filename, structure_load_flags)
       end
 
-      def load_schema(configuration, format = ActiveRecord::Base.schema_format, file = nil) # :nodoc:
+      def load_schema(configuration, format = ActiveRecord::Base.schema_format, file = nil, environment = env) # :nodoc:
         file ||= schema_file(format)
 
+        check_schema_file(file)
+        ActiveRecord::Base.establish_connection(configuration)
+
         case format
         when :ruby
-          check_schema_file(file)
-          ActiveRecord::Base.establish_connection(configuration)
           load(file)
         when :sql
-          check_schema_file(file)
           structure_load(configuration, file)
         else
           raise ArgumentError, "unknown format #{format.inspect}"
         end
         ActiveRecord::InternalMetadata.create_table
-        ActiveRecord::InternalMetadata[:environment] = ActiveRecord::Migrator.current_environment
-      end
-
-      def load_schema_for(*args)
-        ActiveSupport::Deprecation.warn(<<-MSG.squish)
-          This method was renamed to `#load_schema` and will be removed in the future.
-          Use `#load_schema` instead.
-        MSG
-        load_schema(*args)
+        ActiveRecord::InternalMetadata[:environment] = environment
       end
 
       def schema_file(format = ActiveRecord::Base.schema_format)
@@ -249,16 +262,16 @@ module ActiveRecord
       end
 
       def load_schema_current(format = ActiveRecord::Base.schema_format, file = nil, environment = env)
-        each_current_configuration(environment) { |configuration|
-          load_schema configuration, format, file
+        each_current_configuration(environment) { |configuration, configuration_environment|
+          load_schema configuration, format, file, configuration_environment
         }
         ActiveRecord::Base.establish_connection(environment.to_sym)
       end
 
       def check_schema_file(filename)
         unless File.exist?(filename)
-          message = %{#{filename} doesn't exist yet. Run `rails db:migrate` to create it, then try again.}
-          message << %{ If you do not intend to use a database, you should instead alter #{Rails.root}/config/application.rb to limit the frameworks that will be loaded.} if defined?(::Rails)
+          message = %{#{filename} doesn't exist yet. Run `rails db:migrate` to create it, then try again.}.dup
+          message << %{ If you do not intend to use a database, you should instead alter #{Rails.root}/config/application.rb to limit the frameworks that will be loaded.} if defined?(::Rails.root)
           Kernel.abort message
         end
       end
@@ -267,47 +280,58 @@ module ActiveRecord
         if seed_loader
           seed_loader.load_seed
         else
-          raise "You tried to load seed data, but no seed loader is specified. Please specify seed " +
-                "loader with ActiveRecord::Tasks::DatabaseTasks.seed_loader = your_seed_loader\n" +
+          raise "You tried to load seed data, but no seed loader is specified. Please specify seed " \
+                "loader with ActiveRecord::Tasks::DatabaseTasks.seed_loader = your_seed_loader\n" \
                 "Seed loader should respond to load_seed method"
         end
       end
 
+      # Dumps the schema cache in YAML format for the connection into the file
+      #
+      # ==== Examples:
+      #   ActiveRecord::Tasks::DatabaseTasks.dump_schema_cache(ActiveRecord::Base.connection, "tmp/schema_dump.yaml")
+      def dump_schema_cache(conn, filename)
+        conn.schema_cache.clear!
+        conn.data_sources.each { |table| conn.schema_cache.add(table) }
+        open(filename, "wb") { |f| f.write(YAML.dump(conn.schema_cache)) }
+      end
+
       private
 
-      def class_for_adapter(adapter)
-        key = @tasks.keys.detect { |pattern| adapter[pattern] }
-        unless key
-          raise DatabaseNotSupported, "Rake tasks not supported by '#{adapter}' adapter"
+        def class_for_adapter(adapter)
+          _key, task = @tasks.each_pair.detect { |pattern, _task| adapter[pattern] }
+          unless task
+            raise DatabaseNotSupported, "Rake tasks not supported by '#{adapter}' adapter"
+          end
+          task.is_a?(String) ? task.constantize : task
         end
-        @tasks[key]
-      end
 
-      def each_current_configuration(environment)
-        environments = [environment]
-        environments << 'test' if environment == 'development'
+        def each_current_configuration(environment)
+          environments = [environment]
+          environments << "test" if environment == "development"
 
-        configurations = ActiveRecord::Base.configurations.values_at(*environments)
-        configurations.compact.each do |configuration|
-          yield configuration unless configuration['database'].blank?
+          ActiveRecord::Base.configurations.slice(*environments).each do |configuration_environment, configuration|
+            next unless configuration["database"]
+
+            yield configuration, configuration_environment
+          end
         end
-      end
 
-      def each_local_configuration
-        ActiveRecord::Base.configurations.each_value do |configuration|
-          next unless configuration['database']
+        def each_local_configuration
+          ActiveRecord::Base.configurations.each_value do |configuration|
+            next unless configuration["database"]
 
-          if local_database?(configuration)
-            yield configuration
-          else
-            $stderr.puts "This task only modifies local databases. #{configuration['database']} is on a remote host."
+            if local_database?(configuration)
+              yield configuration
+            else
+              $stderr.puts "This task only modifies local databases. #{configuration['database']} is on a remote host."
+            end
           end
         end
-      end
 
-      def local_database?(configuration)
-        configuration['host'].blank? || LOCAL_HOSTS.include?(configuration['host'])
-      end
+        def local_database?(configuration)
+          configuration["host"].blank? || LOCAL_HOSTS.include?(configuration["host"])
+        end
     end
   end
 end
diff --git a/activerecord/lib/active_record/tasks/mysql_database_tasks.rb b/activerecord/lib/active_record/tasks/mysql_database_tasks.rb
index b1a0ad0115..e697fa6def 100644
--- a/activerecord/lib/active_record/tasks/mysql_database_tasks.rb
+++ b/activerecord/lib/active_record/tasks/mysql_database_tasks.rb
@@ -1,8 +1,8 @@
+# frozen_string_literal: true
+
 module ActiveRecord
   module Tasks # :nodoc:
     class MySQLDatabaseTasks # :nodoc:
-      ACCESS_DENIED_ERROR = 1045
-
       delegate :connection, :establish_connection, to: ActiveRecord::Base
 
       def initialize(configuration)
@@ -11,38 +11,24 @@ module ActiveRecord
 
       def create
         establish_connection configuration_without_database
-        connection.create_database configuration['database'], creation_options
+        connection.create_database configuration["database"], creation_options
         establish_connection configuration
       rescue ActiveRecord::StatementInvalid => error
-        if /database exists/ === error.message
+        if error.message.include?("database exists")
           raise DatabaseAlreadyExists
         else
           raise
         end
-      rescue error_class => error
-        if error.respond_to?(:errno) && error.errno == ACCESS_DENIED_ERROR
-          $stdout.print error.message
-          establish_connection root_configuration_without_database
-          connection.create_database configuration['database'], creation_options
-          if configuration['username'] != 'root'
-            connection.execute grant_statement.gsub(/\s+/, ' ').strip
-          end
-          establish_connection configuration
-        else
-          $stderr.puts error.inspect
-          $stderr.puts "Couldn't create database for #{configuration.inspect}, #{creation_options.inspect}"
-          $stderr.puts "(If you set the charset manually, make sure you have a matching collation)" if configuration['encoding']
-        end
       end
 
       def drop
         establish_connection configuration
-        connection.drop_database configuration['database']
+        connection.drop_database configuration["database"]
       end
 
       def purge
         establish_connection configuration
-        connection.recreate_database configuration['database'], creation_options
+        connection.recreate_database configuration["database"], creation_options
       end
 
       def charset
@@ -53,100 +39,77 @@ module ActiveRecord
         connection.collation
       end
 
-      def structure_dump(filename)
+      def structure_dump(filename, extra_flags)
         args = prepare_command_options
         args.concat(["--result-file", "#{filename}"])
         args.concat(["--no-data"])
         args.concat(["--routines"])
         args.concat(["--skip-comments"])
+
+        ignore_tables = ActiveRecord::SchemaDumper.ignore_tables
+        if ignore_tables.any?
+          args += ignore_tables.map { |table| "--ignore-table=#{configuration['database']}.#{table}" }
+        end
+
         args.concat(["#{configuration['database']}"])
+        args.unshift(*extra_flags) if extra_flags
 
-        run_cmd('mysqldump', args, 'dumping')
+        run_cmd("mysqldump", args, "dumping")
       end
 
-      def structure_load(filename)
+      def structure_load(filename, extra_flags)
         args = prepare_command_options
-        args.concat(['--execute', %{SET FOREIGN_KEY_CHECKS = 0; SOURCE #{filename}; SET FOREIGN_KEY_CHECKS = 1}])
+        args.concat(["--execute", %{SET FOREIGN_KEY_CHECKS = 0; SOURCE #{filename}; SET FOREIGN_KEY_CHECKS = 1}])
         args.concat(["--database", "#{configuration['database']}"])
+        args.unshift(*extra_flags) if extra_flags
 
-        run_cmd('mysql', args, 'loading')
+        run_cmd("mysql", args, "loading")
       end
 
       private
 
-      def configuration
-        @configuration
-      end
-
-      def configuration_without_database
-        configuration.merge('database' => nil)
-      end
-
-      def creation_options
-        Hash.new.tap do |options|
-          options[:charset]     = configuration['encoding']   if configuration.include? 'encoding'
-          options[:collation]   = configuration['collation']  if configuration.include? 'collation'
+        def configuration
+          @configuration
         end
-      end
 
-      def error_class
-        if configuration['adapter'] =~ /jdbc/
-          require 'active_record/railties/jdbcmysql_error'
-          ArJdbcMySQL::Error
-        elsif defined?(Mysql2)
-          Mysql2::Error
-        else
-          StandardError
+        def configuration_without_database
+          configuration.merge("database" => nil)
         end
-      end
-
-      def grant_statement
-        <<-SQL
-GRANT ALL PRIVILEGES ON #{configuration['database']}.*
-  TO '#{configuration['username']}'@'localhost'
-IDENTIFIED BY '#{configuration['password']}' WITH GRANT OPTION;
-        SQL
-      end
 
-      def root_configuration_without_database
-        configuration_without_database.merge(
-          'username' => 'root',
-          'password' => root_password
-        )
-      end
-
-      def root_password
-        $stdout.print "Please provide the root password for your MySQL installation\n>"
-        $stdin.gets.strip
-      end
+        def creation_options
+          Hash.new.tap do |options|
+            options[:charset]     = configuration["encoding"]   if configuration.include? "encoding"
+            options[:collation]   = configuration["collation"]  if configuration.include? "collation"
+          end
+        end
 
-      def prepare_command_options
-        args = {
-          'host'      => '--host',
-          'port'      => '--port',
-          'socket'    => '--socket',
-          'username'  => '--user',
-          'password'  => '--password',
-          'encoding'  => '--default-character-set',
-          'sslca'     => '--ssl-ca',
-          'sslcert'   => '--ssl-cert',
-          'sslcapath' => '--ssl-capath',
-          'sslcipher' => '--ssl-cipher',
-          'sslkey'    => '--ssl-key'
-        }.map { |opt, arg| "#{arg}=#{configuration[opt]}" if configuration[opt] }.compact
-
-        args
-      end
+        def prepare_command_options
+          args = {
+            "host"      => "--host",
+            "port"      => "--port",
+            "socket"    => "--socket",
+            "username"  => "--user",
+            "password"  => "--password",
+            "encoding"  => "--default-character-set",
+            "sslca"     => "--ssl-ca",
+            "sslcert"   => "--ssl-cert",
+            "sslcapath" => "--ssl-capath",
+            "sslcipher" => "--ssl-cipher",
+            "sslkey"    => "--ssl-key"
+          }.map { |opt, arg| "#{arg}=#{configuration[opt]}" if configuration[opt] }.compact
+
+          args
+        end
 
-      def run_cmd(cmd, args, action)
-        fail run_cmd_error(cmd, args, action) unless Kernel.system(cmd, *args)
-      end
+        def run_cmd(cmd, args, action)
+          fail run_cmd_error(cmd, args, action) unless Kernel.system(cmd, *args)
+        end
 
-      def run_cmd_error(cmd, args, action)
-        msg = "failed to execute: `#{cmd}`\n"
-        msg << "Please check the output above for any errors and make sure that `#{cmd}` is installed in your PATH and has proper permissions.\n\n"
-        msg
-      end
+        def run_cmd_error(cmd, args, action)
+          msg = "failed to execute: `#{cmd}`\n".dup
+          msg << "Please check the output above for any errors and make sure that `#{cmd}` is installed in your PATH and has proper permissions.\n\n"
+          msg
+        end
     end
   end
 end
diff --git a/activerecord/lib/active_record/tasks/postgresql_database_tasks.rb b/activerecord/lib/active_record/tasks/postgresql_database_tasks.rb
index b19ab57ee4..647e066137 100644
--- a/activerecord/lib/active_record/tasks/postgresql_database_tasks.rb
+++ b/activerecord/lib/active_record/tasks/postgresql_database_tasks.rb
@@ -1,8 +1,13 @@
+# frozen_string_literal: true
+
+require "tempfile"
+
 module ActiveRecord
   module Tasks # :nodoc:
     class PostgreSQLDatabaseTasks # :nodoc:
-      DEFAULT_ENCODING = ENV['CHARSET'] || 'utf8'
-      ON_ERROR_STOP_1 = 'ON_ERROR_STOP=1'.freeze
+      DEFAULT_ENCODING = ENV["CHARSET"] || "utf8"
+      ON_ERROR_STOP_1 = "ON_ERROR_STOP=1".freeze
+      SQL_COMMENT_BEGIN = "--".freeze
 
       delegate :connection, :establish_connection, :clear_active_connections!,
         to: ActiveRecord::Base
@@ -13,11 +18,11 @@ module ActiveRecord
 
       def create(master_established = false)
         establish_master_connection unless master_established
-        connection.create_database configuration['database'],
-          configuration.merge('encoding' => encoding)
+        connection.create_database configuration["database"],
+          configuration.merge("encoding" => encoding)
         establish_connection configuration
       rescue ActiveRecord::StatementInvalid => error
-        if /database .* already exists/ === error.message
+        if error.cause.is_a?(PG::DuplicateDatabase)
           raise DatabaseAlreadyExists
         else
           raise
@@ -26,7 +31,7 @@ module ActiveRecord
 
       def drop
         establish_master_connection
-        connection.drop_database configuration['database']
+        connection.drop_database configuration["database"]
       end
 
       def charset
@@ -43,69 +48,96 @@ module ActiveRecord
         create true
       end
 
-      def structure_dump(filename)
+      def structure_dump(filename, extra_flags)
         set_psql_env
 
-        search_path = case ActiveRecord::Base.dump_schemas
-        when :schema_search_path
-          configuration['schema_search_path']
-        when :all
-          nil
-        when String
-          ActiveRecord::Base.dump_schemas
-        end
+        search_path = \
+          case ActiveRecord::Base.dump_schemas
+          when :schema_search_path
+            configuration["schema_search_path"]
+          when :all
+            nil
+          when String
+            ActiveRecord::Base.dump_schemas
+          end
 
-        args = ['-s', '-x', '-O', '-f', filename]
+        args = ["-s", "-x", "-O", "-f", filename]
+        args.concat(Array(extra_flags)) if extra_flags
         unless search_path.blank?
-          args += search_path.split(',').map do |part|
+          args += search_path.split(",").map do |part|
             "--schema=#{part.strip}"
           end
         end
-        args << configuration['database']
-        run_cmd('pg_dump', args, 'dumping')
+
+        ignore_tables = ActiveRecord::SchemaDumper.ignore_tables
+        if ignore_tables.any?
+          args += ignore_tables.flat_map { |table| ["-T", table] }
+        end
+
+        args << configuration["database"]
+        run_cmd("pg_dump", args, "dumping")
+        remove_sql_header_comments(filename)
         File.open(filename, "a") { |f| f << "SET search_path TO #{connection.schema_search_path};\n\n" }
       end
 
-      def structure_load(filename)
+      def structure_load(filename, extra_flags)
         set_psql_env
-        args = [ '-v', ON_ERROR_STOP_1, '-q', '-f', filename, configuration['database'] ]
-        run_cmd('psql', args, 'loading' )
+        args = ["-v", ON_ERROR_STOP_1, "-q", "-f", filename]
+        args.concat(Array(extra_flags)) if extra_flags
+        args << configuration["database"]
+        run_cmd("psql", args, "loading")
       end
 
       private
 
-      def configuration
-        @configuration
-      end
+        def configuration
+          @configuration
+        end
 
-      def encoding
-        configuration['encoding'] || DEFAULT_ENCODING
-      end
+        def encoding
+          configuration["encoding"] || DEFAULT_ENCODING
+        end
 
-      def establish_master_connection
-        establish_connection configuration.merge(
-          'database'           => 'postgres',
-          'schema_search_path' => 'public'
-        )
-      end
+        def establish_master_connection
+          establish_connection configuration.merge(
+            "database"           => "postgres",
+            "schema_search_path" => "public"
+          )
+        end
 
-      def set_psql_env
-        ENV['PGHOST']     = configuration['host']          if configuration['host']
-        ENV['PGPORT']     = configuration['port'].to_s     if configuration['port']
-        ENV['PGPASSWORD'] = configuration['password'].to_s if configuration['password']
-        ENV['PGUSER']     = configuration['username'].to_s if configuration['username']
-      end
+        def set_psql_env
+          ENV["PGHOST"]     = configuration["host"]          if configuration["host"]
+          ENV["PGPORT"]     = configuration["port"].to_s     if configuration["port"]
+          ENV["PGPASSWORD"] = configuration["password"].to_s if configuration["password"]
+          ENV["PGUSER"]     = configuration["username"].to_s if configuration["username"]
+        end
 
-      def run_cmd(cmd, args, action)
-        fail run_cmd_error(cmd, args, action) unless Kernel.system(cmd, *args)
-      end
+        def run_cmd(cmd, args, action)
+          fail run_cmd_error(cmd, args, action) unless Kernel.system(cmd, *args)
+        end
 
-      def run_cmd_error(cmd, args, action)
-        msg = "failed to execute:\n"
-        msg << "#{cmd} #{args.join(' ')}\n\n"
-        msg << "Please check the output above for any errors and make sure that `#{cmd}` is installed in your PATH and has proper permissions.\n\n"
-        msg
-      end
+        def run_cmd_error(cmd, args, action)
+          msg = "failed to execute:\n".dup
+          msg << "#{cmd} #{args.join(' ')}\n\n"
+          msg << "Please check the output above for any errors and make sure that `#{cmd}` is installed in your PATH and has proper permissions.\n\n"
+          msg
+        end
+
+        def remove_sql_header_comments(filename)
+          removing_comments = true
+          tempfile = Tempfile.open("uncommented_structure.sql")
+          begin
+            File.foreach(filename) do |line|
+              unless removing_comments && (line.start_with?(SQL_COMMENT_BEGIN) || line.blank?)
+                tempfile << line
+                removing_comments = false
+              end
+            end
+          ensure
+            tempfile.close
+          end
+          FileUtils.cp(tempfile.path, filename)
+        end
     end
   end
 end
diff --git a/activerecord/lib/active_record/tasks/sqlite_database_tasks.rb b/activerecord/lib/active_record/tasks/sqlite_database_tasks.rb
index 9ec3c8a94a..dfe599c4dd 100644
--- a/activerecord/lib/active_record/tasks/sqlite_database_tasks.rb
+++ b/activerecord/lib/active_record/tasks/sqlite_database_tasks.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActiveRecord
   module Tasks # :nodoc:
     class SQLiteDatabaseTasks # :nodoc:
@@ -8,20 +10,20 @@ module ActiveRecord
       end
 
       def create
-        raise DatabaseAlreadyExists if File.exist?(configuration['database'])
+        raise DatabaseAlreadyExists if File.exist?(configuration["database"])
 
         establish_connection configuration
         connection
       end
 
       def drop
-        require 'pathname'
-        path = Pathname.new configuration['database']
+        require "pathname"
+        path = Pathname.new configuration["database"]
         file = path.absolute? ? path.to_s : File.join(root, path)
 
         FileUtils.rm(file)
       rescue Errno::ENOENT => error
-        raise NoDatabaseError.new(error.message, error)
+        raise NoDatabaseError.new(error.message)
       end
 
       def purge
@@ -35,25 +37,47 @@ module ActiveRecord
         connection.encoding
       end
 
-      def structure_dump(filename)
-        dbfile = configuration['database']
-        `sqlite3 #{dbfile} .schema > #{filename}`
+      def structure_dump(filename, extra_flags)
+        args = []
+        args.concat(Array(extra_flags)) if extra_flags
+        args << configuration["database"]
+
+        ignore_tables = ActiveRecord::SchemaDumper.ignore_tables
+        if ignore_tables.any?
+          condition = ignore_tables.map { |table| connection.quote(table) }.join(", ")
+          args << "SELECT sql FROM sqlite_master WHERE tbl_name NOT IN (#{condition}) ORDER BY tbl_name, type DESC, name"
+        else
+          args << ".schema"
+        end
+        run_cmd("sqlite3", args, filename)
       end
 
-      def structure_load(filename)
-        dbfile = configuration['database']
-        `sqlite3 #{dbfile} < "#{filename}"`
+      def structure_load(filename, extra_flags)
+        dbfile = configuration["database"]
+        flags = extra_flags.join(" ") if extra_flags
+        `sqlite3 #{flags} #{dbfile} < "#{filename}"`
       end
 
       private
 
-      def configuration
-        @configuration
-      end
+        def configuration
+          @configuration
+        end
 
-      def root
-        @root
-      end
+        def root
+          @root
+        end
+
+        def run_cmd(cmd, args, out)
+          fail run_cmd_error(cmd, args) unless Kernel.system(cmd, *args, out: out)
+        end
+
+        def run_cmd_error(cmd, args)
+          msg = "failed to execute:\n".dup
+          msg << "#{cmd} #{args.join(' ')}\n\n"
+          msg << "Please check the output above for any errors and make sure that `#{cmd}` is installed in your PATH and has proper permissions.\n\n"
+          msg
+        end
     end
   end
 end
diff --git a/activerecord/lib/active_record/timestamp.rb b/activerecord/lib/active_record/timestamp.rb
index d9c18a5e38..5da3759e5a 100644
--- a/activerecord/lib/active_record/timestamp.rb
+++ b/activerecord/lib/active_record/timestamp.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActiveRecord
   # = Active Record \Timestamp
   #
@@ -42,8 +44,7 @@ module ActiveRecord
     extend ActiveSupport::Concern
 
     included do
-      class_attribute :record_timestamps
-      self.record_timestamps = true
+      class_attribute :record_timestamps, default: true
     end
 
     def initialize_dup(other) # :nodoc:
@@ -51,16 +52,42 @@ module ActiveRecord
       clear_timestamp_attributes
     end
 
+    class_methods do
+      private
+        def timestamp_attributes_for_create_in_model
+          timestamp_attributes_for_create.select { |c| column_names.include?(c) }
+        end
+
+        def timestamp_attributes_for_update_in_model
+          timestamp_attributes_for_update.select { |c| column_names.include?(c) }
+        end
+
+        def all_timestamp_attributes_in_model
+          timestamp_attributes_for_create_in_model + timestamp_attributes_for_update_in_model
+        end
+
+        def timestamp_attributes_for_create
+          ["created_at", "created_on"]
+        end
+
+        def timestamp_attributes_for_update
+          ["updated_at", "updated_on"]
+        end
+
+        def current_time_from_proper_timezone
+          default_timezone == :utc ? Time.now.utc : Time.now
+        end
+    end
+
   private
 
     def _create_record
-      if self.record_timestamps
+      if record_timestamps
         current_time = current_time_from_proper_timezone
 
-        all_timestamp_attributes.each do |column|
-          column = column.to_s
-          if has_attribute?(column) && !attribute_present?(column)
-            write_attribute(column, current_time)
+        all_timestamp_attributes_in_model.each do |column|
+          if !attribute_present?(column)
+            _write_attribute(column, current_time)
           end
         end
       end
@@ -73,43 +100,34 @@ module ActiveRecord
         current_time = current_time_from_proper_timezone
 
         timestamp_attributes_for_update_in_model.each do |column|
-          column = column.to_s
-          next if attribute_changed?(column)
-          write_attribute(column, current_time)
+          next if will_save_change_to_attribute?(column)
+          _write_attribute(column, current_time)
         end
       end
       super(*args)
     end
 
     def should_record_timestamps?
-      self.record_timestamps && (!partial_writes? || changed?)
+      record_timestamps && (!partial_writes? || has_changes_to_save?)
     end
 
     def timestamp_attributes_for_create_in_model
-      timestamp_attributes_for_create.select { |c| self.class.column_names.include?(c.to_s) }
+      self.class.send(:timestamp_attributes_for_create_in_model)
     end
 
     def timestamp_attributes_for_update_in_model
-      timestamp_attributes_for_update.select { |c| self.class.column_names.include?(c.to_s) }
+      self.class.send(:timestamp_attributes_for_update_in_model)
     end
 
     def all_timestamp_attributes_in_model
-      timestamp_attributes_for_create_in_model + timestamp_attributes_for_update_in_model
+      self.class.send(:all_timestamp_attributes_in_model)
     end
 
-    def timestamp_attributes_for_update
-      [:updated_at, :updated_on]
-    end
-
-    def timestamp_attributes_for_create
-      [:created_at, :created_on]
-    end
-
-    def all_timestamp_attributes
-      timestamp_attributes_for_create + timestamp_attributes_for_update
+    def current_time_from_proper_timezone
+      self.class.send(:current_time_from_proper_timezone)
     end
 
-    def max_updated_column_timestamp(timestamp_names = timestamp_attributes_for_update)
+    def max_updated_column_timestamp(timestamp_names = timestamp_attributes_for_update_in_model)
       timestamp_names
         .map { |attr| self[attr] }
         .compact
@@ -117,10 +135,6 @@ module ActiveRecord
         .max
     end
 
-    def current_time_from_proper_timezone
-      self.class.default_timezone == :utc ? Time.now.utc : Time.now
-    end
-
     # Clear attributes and changed_attributes
     def clear_timestamp_attributes
       all_timestamp_attributes_in_model.each do |attribute_name|
diff --git a/activerecord/lib/active_record/touch_later.rb b/activerecord/lib/active_record/touch_later.rb
index 9a80a63e28..f70b7c50a2 100644
--- a/activerecord/lib/active_record/touch_later.rb
+++ b/activerecord/lib/active_record/touch_later.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActiveRecord
   # = Active Record Touch Later
   module TouchLater
@@ -8,7 +10,12 @@ module ActiveRecord
     end
 
     def touch_later(*names) # :nodoc:
-      raise ActiveRecordError, "cannot touch on a new record object" unless persisted?
+      unless persisted?
+        raise ActiveRecordError, <<-MSG.squish
+          cannot touch on a new or destroyed record object. Consider using
+          persisted?, new_record?, or destroyed? before touching
+        MSG
+      end
 
       @_defer_touch_attrs ||= timestamp_attributes_for_update_in_model
       @_defer_touch_attrs |= names
@@ -20,7 +27,7 @@ module ActiveRecord
       # touch the parents as we are not calling the after_save callbacks
       self.class.reflect_on_all_associations(:belongs_to).each do |r|
         if touch = r.options[:touch]
-          ActiveRecord::Associations::Builder::BelongsTo.touch_record(self, r.foreign_key, r.name, touch, :touch_later)
+          ActiveRecord::Associations::Builder::BelongsTo.touch_record(self, changes_to_save, r.foreign_key, r.name, touch, :touch_later)
         end
       end
     end
@@ -53,6 +60,5 @@ module ActiveRecord
       def belongs_to_touch_method
         :touch_later
       end
-
   end
 end
diff --git a/activerecord/lib/active_record/transactions.rb b/activerecord/lib/active_record/transactions.rb
index 77c2845d88..97cba5d1c7 100644
--- a/activerecord/lib/active_record/transactions.rb
+++ b/activerecord/lib/active_record/transactions.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActiveRecord
   # See ActiveRecord::Transactions::ClassMethods for documentation.
   module Transactions
@@ -11,7 +13,6 @@ module ActiveRecord
                        :before_commit_without_transaction_enrollment,
                        :commit_without_transaction_enrollment,
                        :rollback_without_transaction_enrollment,
-                       terminator: deprecated_false_terminator,
                        scope: [:kind, :name]
     end
 
@@ -124,7 +125,7 @@ module ActiveRecord
     #     # statement will cause a PostgreSQL error, even though the unique
     #     # constraint is no longer violated:
     #     Number.create(i: 1)
-    #     # => "PGError: ERROR:  current transaction is aborted, commands
+    #     # => "PG::Error: ERROR:  current transaction is aborted, commands
     #     #     ignored until end of transaction block"
     #   end
     #
@@ -169,7 +170,7 @@ module ActiveRecord
     # writing, the only database that we're aware of that supports true nested
     # transactions, is MS-SQL. Because of this, Active Record emulates nested
     # transactions by using savepoints on MySQL and PostgreSQL. See
-    # http://dev.mysql.com/doc/refman/5.7/en/savepoint.html
+    # https://dev.mysql.com/doc/refman/5.7/en/savepoint.html
     # for more information about savepoints.
     #
     # === \Callbacks
@@ -189,8 +190,8 @@ module ActiveRecord
     #
     # === Caveats
     #
-    # If you're on MySQL, then do not use DDL operations in nested transactions
-    # blocks that are emulated with savepoints. That is, do not execute statements
+    # If you're on MySQL, then do not use Data Definition Language (DDL) operations in nested
+    # transactions blocks that are emulated with savepoints. That is, do not execute statements
     # like 'CREATE TABLE' inside such blocks. This is because MySQL automatically
     # releases all savepoints upon executing a DDL operation. When +transaction+
     # is finished and tries to release the savepoint it created earlier, a
@@ -274,35 +275,25 @@ module ActiveRecord
         set_callback(:rollback_without_transaction_enrollment, :after, *args, &block)
       end
 
-      def raise_in_transactional_callbacks
-        ActiveSupport::Deprecation.warn('ActiveRecord::Base.raise_in_transactional_callbacks is deprecated and will be removed without replacement.')
-        true
-      end
-
-      def raise_in_transactional_callbacks=(value)
-        ActiveSupport::Deprecation.warn('ActiveRecord::Base.raise_in_transactional_callbacks= is deprecated, has no effect and will be removed without replacement.')
-        value
-      end
-
       private
 
-      def set_options_for_callbacks!(args, enforced_options = {})
-        options = args.extract_options!.merge!(enforced_options)
-        args << options
+        def set_options_for_callbacks!(args, enforced_options = {})
+          options = args.extract_options!.merge!(enforced_options)
+          args << options
 
-        if options[:on]
-          fire_on = Array(options[:on])
-          assert_valid_transaction_action(fire_on)
-          options[:if] = Array(options[:if])
-          options[:if] << "transaction_include_any_action?(#{fire_on})"
+          if options[:on]
+            fire_on = Array(options[:on])
+            assert_valid_transaction_action(fire_on)
+            options[:if] = Array(options[:if])
+            options[:if].unshift(-> { transaction_include_any_action?(fire_on) })
+          end
         end
-      end
 
-      def assert_valid_transaction_action(actions)
-        if (actions - ACTIONS).any?
-          raise ArgumentError, ":on conditions for after_commit and after_rollback callbacks have to be one of #{ACTIONS}"
+        def assert_valid_transaction_action(actions)
+          if (actions - ACTIONS).any?
+            raise ArgumentError, ":on conditions for after_commit and after_rollback callbacks have to be one of #{ACTIONS}"
+          end
         end
-      end
     end
 
     # See ActiveRecord::Transactions::ClassMethods for detailed documentation.
@@ -407,103 +398,102 @@ module ActiveRecord
       end
     end
 
-    protected
-
-    # Save the new record state and id of a record so it can be restored later if a transaction fails.
-    def remember_transaction_record_state #:nodoc:
-      @_start_transaction_state[:id] = id
-      @_start_transaction_state.reverse_merge!(
-        new_record: @new_record,
-        destroyed: @destroyed,
-        frozen?: frozen?,
-      )
-      @_start_transaction_state[:level] = (@_start_transaction_state[:level] || 0) + 1
-    end
+    private
 
-    # Clear the new record state and id of a record.
-    def clear_transaction_record_state #:nodoc:
-      @_start_transaction_state[:level] = (@_start_transaction_state[:level] || 0) - 1
-      force_clear_transaction_record_state if @_start_transaction_state[:level] < 1
-    end
+      # Save the new record state and id of a record so it can be restored later if a transaction fails.
+      def remember_transaction_record_state
+        @_start_transaction_state[:id] = id
+        @_start_transaction_state.reverse_merge!(
+          new_record: @new_record,
+          destroyed: @destroyed,
+          frozen?: frozen?,
+        )
+        @_start_transaction_state[:level] = (@_start_transaction_state[:level] || 0) + 1
+      end
 
-    # Force to clear the transaction record state.
-    def force_clear_transaction_record_state #:nodoc:
-      @_start_transaction_state.clear
-    end
+      # Clear the new record state and id of a record.
+      def clear_transaction_record_state
+        @_start_transaction_state[:level] = (@_start_transaction_state[:level] || 0) - 1
+        force_clear_transaction_record_state if @_start_transaction_state[:level] < 1
+      end
+
+      # Force to clear the transaction record state.
+      def force_clear_transaction_record_state
+        @_start_transaction_state.clear
+      end
 
-    # Restore the new record state and id of a record that was previously saved by a call to save_record_state.
-    def restore_transaction_record_state(force = false) #:nodoc:
-      unless @_start_transaction_state.empty?
-        transaction_level = (@_start_transaction_state[:level] || 0) - 1
-        if transaction_level < 1 || force
-          restore_state = @_start_transaction_state
-          thaw
-          @new_record = restore_state[:new_record]
-          @destroyed  = restore_state[:destroyed]
-          pk = self.class.primary_key
-          if pk && read_attribute(pk) != restore_state[:id]
-            write_attribute(pk, restore_state[:id])
+      # Restore the new record state and id of a record that was previously saved by a call to save_record_state.
+      def restore_transaction_record_state(force = false)
+        unless @_start_transaction_state.empty?
+          transaction_level = (@_start_transaction_state[:level] || 0) - 1
+          if transaction_level < 1 || force
+            restore_state = @_start_transaction_state
+            thaw
+            @new_record = restore_state[:new_record]
+            @destroyed  = restore_state[:destroyed]
+            pk = self.class.primary_key
+            if pk && _read_attribute(pk) != restore_state[:id]
+              _write_attribute(pk, restore_state[:id])
+            end
+            freeze if restore_state[:frozen?]
           end
-          freeze if restore_state[:frozen?]
         end
       end
-    end
 
-    # Determine if a record was created or destroyed in a transaction. State should be one of :new_record or :destroyed.
-    def transaction_record_state(state) #:nodoc:
-      @_start_transaction_state[state]
-    end
+      # Determine if a record was created or destroyed in a transaction. State should be one of :new_record or :destroyed.
+      def transaction_record_state(state)
+        @_start_transaction_state[state]
+      end
 
-    # Determine if a transaction included an action for :create, :update, or :destroy. Used in filtering callbacks.
-    def transaction_include_any_action?(actions) #:nodoc:
-      actions.any? do |action|
-        case action
-        when :create
-          transaction_record_state(:new_record)
-        when :destroy
-          destroyed?
-        when :update
-          !(transaction_record_state(:new_record) || destroyed?)
+      # Determine if a transaction included an action for :create, :update, or :destroy. Used in filtering callbacks.
+      def transaction_include_any_action?(actions)
+        actions.any? do |action|
+          case action
+          when :create
+            transaction_record_state(:new_record)
+          when :destroy
+            defined?(@_trigger_destroy_callback) && @_trigger_destroy_callback
+          when :update
+            !(transaction_record_state(:new_record) || destroyed?) &&
+              (defined?(@_trigger_update_callback) && @_trigger_update_callback)
+          end
         end
       end
-    end
 
-    private
-
-    def set_transaction_state(state) # :nodoc:
-      @transaction_state = state
-    end
+      def set_transaction_state(state)
+        @transaction_state = state
+      end
 
-    def has_transactional_callbacks? # :nodoc:
-      !_rollback_callbacks.empty? || !_commit_callbacks.empty? || !_before_commit_callbacks.empty?
-    end
+      def has_transactional_callbacks?
+        !_rollback_callbacks.empty? || !_commit_callbacks.empty? || !_before_commit_callbacks.empty?
+      end
 
-    # Updates the attributes on this particular Active Record object so that
-    # if it's associated with a transaction, then the state of the Active Record
-    # object will be updated to reflect the current state of the transaction
-    #
-    # The +@transaction_state+ variable stores the states of the associated
-    # transaction. This relies on the fact that a transaction can only be in
-    # one rollback or commit (otherwise a list of states would be required)
-    # Each Active Record object inside of a transaction carries that transaction's
-    # TransactionState.
-    #
-    # This method checks to see if the ActiveRecord object's state reflects
-    # the TransactionState, and rolls back or commits the Active Record object
-    # as appropriate.
-    #
-    # Since Active Record objects can be inside multiple transactions, this
-    # method recursively goes through the parent of the TransactionState and
-    # checks if the Active Record object reflects the state of the object.
-    def sync_with_transaction_state
-      update_attributes_from_transaction_state(@transaction_state)
-    end
+      # Updates the attributes on this particular Active Record object so that
+      # if it's associated with a transaction, then the state of the Active Record
+      # object will be updated to reflect the current state of the transaction.
+      #
+      # The <tt>@transaction_state</tt> variable stores the states of the associated
+      # transaction. This relies on the fact that a transaction can only be in
+      # one rollback or commit (otherwise a list of states would be required).
+      # Each Active Record object inside of a transaction carries that transaction's
+      # TransactionState.
+      #
+      # This method checks to see if the ActiveRecord object's state reflects
+      # the TransactionState, and rolls back or commits the Active Record object
+      # as appropriate.
+      #
+      # Since Active Record objects can be inside multiple transactions, this
+      # method recursively goes through the parent of the TransactionState and
+      # checks if the Active Record object reflects the state of the object.
+      def sync_with_transaction_state
+        update_attributes_from_transaction_state(@transaction_state)
+      end
 
-    def update_attributes_from_transaction_state(transaction_state)
-      if transaction_state && transaction_state.finalized?
-        restore_transaction_record_state if transaction_state.rolledback?
-        clear_transaction_record_state
+      def update_attributes_from_transaction_state(transaction_state)
+        if transaction_state && transaction_state.finalized?
+          restore_transaction_record_state if transaction_state.rolledback?
+          clear_transaction_record_state if transaction_state.fully_completed?
+        end
       end
-    end
   end
 end
diff --git a/activerecord/lib/active_record/translation.rb b/activerecord/lib/active_record/translation.rb
index ddcb5f2a7a..3cf70eafb8 100644
--- a/activerecord/lib/active_record/translation.rb
+++ b/activerecord/lib/active_record/translation.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActiveRecord
   module Translation
     include ActiveModel::Translation
diff --git a/activerecord/lib/active_record/type.rb b/activerecord/lib/active_record/type.rb
index 4911d93dd9..c303186ef2 100644
--- a/activerecord/lib/active_record/type.rb
+++ b/activerecord/lib/active_record/type.rb
@@ -1,17 +1,22 @@
-require 'active_model/type'
+# frozen_string_literal: true
 
-require 'active_record/type/internal/abstract_json'
-require 'active_record/type/internal/timezone'
+require "active_model/type"
 
-require 'active_record/type/date'
-require 'active_record/type/date_time'
-require 'active_record/type/time'
+require "active_record/type/internal/timezone"
 
-require 'active_record/type/serialized'
-require 'active_record/type/adapter_specific_registry'
+require "active_record/type/date"
+require "active_record/type/date_time"
+require "active_record/type/decimal_without_scale"
+require "active_record/type/json"
+require "active_record/type/time"
+require "active_record/type/text"
+require "active_record/type/unsigned_integer"
 
-require 'active_record/type/type_map'
-require 'active_record/type/hash_lookup_type_map'
+require "active_record/type/serialized"
+require "active_record/type/adapter_specific_registry"
+
+require "active_record/type/type_map"
+require "active_record/type/hash_lookup_type_map"
 
 module ActiveRecord
   module Type
@@ -37,6 +42,10 @@ module ActiveRecord
         registry.lookup(*args, adapter: adapter, **kwargs)
       end
 
+      def default_value # :nodoc:
+        @default_value ||= Value.new
+      end
+
       private
 
       def current_adapter_name
@@ -49,12 +58,9 @@ module ActiveRecord
     Binary = ActiveModel::Type::Binary
     Boolean = ActiveModel::Type::Boolean
     Decimal = ActiveModel::Type::Decimal
-    DecimalWithoutScale = ActiveModel::Type::DecimalWithoutScale
     Float = ActiveModel::Type::Float
     Integer = ActiveModel::Type::Integer
     String = ActiveModel::Type::String
-    Text = ActiveModel::Type::Text
-    UnsignedInteger = ActiveModel::Type::UnsignedInteger
     Value = ActiveModel::Type::Value
 
     register(:big_integer, Type::BigInteger, override: false)
@@ -65,6 +71,7 @@ module ActiveRecord
     register(:decimal, Type::Decimal, override: false)
     register(:float, Type::Float, override: false)
     register(:integer, Type::Integer, override: false)
+    register(:json, Type::Json, override: false)
     register(:string, Type::String, override: false)
     register(:text, Type::Text, override: false)
     register(:time, Type::Time, override: false)
diff --git a/activerecord/lib/active_record/type/adapter_specific_registry.rb b/activerecord/lib/active_record/type/adapter_specific_registry.rb
index d440eac619..e7468aa542 100644
--- a/activerecord/lib/active_record/type/adapter_specific_registry.rb
+++ b/activerecord/lib/active_record/type/adapter_specific_registry.rb
@@ -1,4 +1,6 @@
-require 'active_model/type/registry'
+# frozen_string_literal: true
+
+require "active_model/type/registry"
 
 module ActiveRecord
   # :stopdoc:
@@ -10,15 +12,15 @@ module ActiveRecord
 
       private
 
-      def registration_klass
-        Registration
-      end
+        def registration_klass
+          Registration
+        end
 
-      def find_registration(symbol, *args)
-        registrations
-          .select { |registration| registration.matches?(symbol, *args) }
-          .max
-      end
+        def find_registration(symbol, *args)
+          registrations
+            .select { |registration| registration.matches?(symbol, *args) }
+            .max
+        end
     end
 
     class Registration
@@ -50,44 +52,46 @@ module ActiveRecord
         priority <=> other.priority
       end
 
+      # TODO Change this to private once we've dropped Ruby 2.2 support.
+      # Workaround for Ruby 2.2 "private attribute?" warning.
       protected
 
-      attr_reader :name, :block, :adapter, :override
-
-      def priority
-        result = 0
-        if adapter
-          result |= 1
-        end
-        if override
-          result |= 2
+        attr_reader :name, :block, :adapter, :override
+
+        def priority
+          result = 0
+          if adapter
+            result |= 1
+          end
+          if override
+            result |= 2
+          end
+          result
         end
-        result
-      end
 
-      def priority_except_adapter
-        priority & 0b111111100
-      end
+        def priority_except_adapter
+          priority & 0b111111100
+        end
 
       private
 
-      def matches_adapter?(adapter: nil, **)
-        (self.adapter.nil? || adapter == self.adapter)
-      end
+        def matches_adapter?(adapter: nil, **)
+          (self.adapter.nil? || adapter == self.adapter)
+        end
 
-      def conflicts_with?(other)
-        same_priority_except_adapter?(other) &&
-          has_adapter_conflict?(other)
-      end
+        def conflicts_with?(other)
+          same_priority_except_adapter?(other) &&
+            has_adapter_conflict?(other)
+        end
 
-      def same_priority_except_adapter?(other)
-        priority_except_adapter == other.priority_except_adapter
-      end
+        def same_priority_except_adapter?(other)
+          priority_except_adapter == other.priority_except_adapter
+        end
 
-      def has_adapter_conflict?(other)
-        (override.nil? && other.adapter) ||
-          (adapter && other.override.nil?)
-      end
+        def has_adapter_conflict?(other)
+          (override.nil? && other.adapter) ||
+            (adapter && other.override.nil?)
+        end
     end
 
     class DecorationRegistration < Registration
@@ -110,17 +114,19 @@ module ActiveRecord
         super | 4
       end
 
+      # TODO Change this to private once we've dropped Ruby 2.2 support.
+      # Workaround for Ruby 2.2 "private attribute?" warning.
       protected
 
-      attr_reader :options, :klass
+        attr_reader :options, :klass
 
       private
 
-      def matches_options?(**kwargs)
-        options.all? do |key, value|
-          kwargs[key] == value
+        def matches_options?(**kwargs)
+          options.all? do |key, value|
+            kwargs[key] == value
+          end
         end
-      end
     end
   end
 
diff --git a/activerecord/lib/active_record/type/date.rb b/activerecord/lib/active_record/type/date.rb
index ccafed054e..8177074a20 100644
--- a/activerecord/lib/active_record/type/date.rb
+++ b/activerecord/lib/active_record/type/date.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActiveRecord
   module Type
     class Date < ActiveModel::Type::Date
diff --git a/activerecord/lib/active_record/type/date_time.rb b/activerecord/lib/active_record/type/date_time.rb
index 1fb9380ecd..4acde6b9f8 100644
--- a/activerecord/lib/active_record/type/date_time.rb
+++ b/activerecord/lib/active_record/type/date_time.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActiveRecord
   module Type
     class DateTime < ActiveModel::Type::DateTime
diff --git a/activerecord/lib/active_record/type/decimal_without_scale.rb b/activerecord/lib/active_record/type/decimal_without_scale.rb
new file mode 100644
index 0000000000..a207940dc7
--- /dev/null
+++ b/activerecord/lib/active_record/type/decimal_without_scale.rb
@@ -0,0 +1,15 @@
+# frozen_string_literal: true
+
+module ActiveRecord
+  module Type
+    class DecimalWithoutScale < ActiveModel::Type::BigInteger # :nodoc:
+      def type
+        :decimal
+      end
+
+      def type_cast_for_schema(value)
+        value.to_s.inspect
+      end
+    end
+  end
+end
diff --git a/activerecord/lib/active_record/type/hash_lookup_type_map.rb b/activerecord/lib/active_record/type/hash_lookup_type_map.rb
index 3b01e3f8ca..db9853fbcc 100644
--- a/activerecord/lib/active_record/type/hash_lookup_type_map.rb
+++ b/activerecord/lib/active_record/type/hash_lookup_type_map.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActiveRecord
   module Type
     class HashLookupTypeMap < TypeMap # :nodoc:
@@ -15,9 +17,9 @@ module ActiveRecord
 
       private
 
-      def perform_fetch(type, *args, &block)
-        @mapping.fetch(type, block).call(type, *args)
-      end
+        def perform_fetch(type, *args, &block)
+          @mapping.fetch(type, block).call(type, *args)
+        end
     end
   end
 end
diff --git a/activerecord/lib/active_record/type/internal/abstract_json.rb b/activerecord/lib/active_record/type/internal/abstract_json.rb
deleted file mode 100644
index 513c938088..0000000000
--- a/activerecord/lib/active_record/type/internal/abstract_json.rb
+++ /dev/null
@@ -1,29 +0,0 @@
-module ActiveRecord
-  module Type
-    module Internal # :nodoc:
-      class AbstractJson < ActiveModel::Type::Value # :nodoc:
-        include ActiveModel::Type::Helpers::Mutable
-
-        def type
-          :json
-        end
-
-        def deserialize(value)
-          if value.is_a?(::String)
-            ::ActiveSupport::JSON.decode(value) rescue nil
-          else
-            value
-          end
-        end
-
-        def serialize(value)
-          ::ActiveSupport::JSON.encode(value)
-        end
-
-        def accessor
-          ActiveRecord::Store::StringKeyedHashAccessor
-        end
-      end
-    end
-  end
-end
diff --git a/activerecord/lib/active_record/type/internal/timezone.rb b/activerecord/lib/active_record/type/internal/timezone.rb
index 947e06158a..3059755752 100644
--- a/activerecord/lib/active_record/type/internal/timezone.rb
+++ b/activerecord/lib/active_record/type/internal/timezone.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActiveRecord
   module Type
     module Internal
diff --git a/activerecord/lib/active_record/type/json.rb b/activerecord/lib/active_record/type/json.rb
new file mode 100644
index 0000000000..3f9ff22796
--- /dev/null
+++ b/activerecord/lib/active_record/type/json.rb
@@ -0,0 +1,30 @@
+# frozen_string_literal: true
+
+module ActiveRecord
+  module Type
+    class Json < ActiveModel::Type::Value
+      include ActiveModel::Type::Helpers::Mutable
+
+      def type
+        :json
+      end
+
+      def deserialize(value)
+        return value unless value.is_a?(::String)
+        ActiveSupport::JSON.decode(value) rescue nil
+      end
+
+      def serialize(value)
+        ActiveSupport::JSON.encode(value) unless value.nil?
+      end
+
+      def changed_in_place?(raw_old_value, new_value)
+        deserialize(raw_old_value) != new_value
+      end
+
+      def accessor
+        ActiveRecord::Store::StringKeyedHashAccessor
+      end
+    end
+  end
+end
diff --git a/activerecord/lib/active_record/type/serialized.rb b/activerecord/lib/active_record/type/serialized.rb
index a3a5241780..e882784691 100644
--- a/activerecord/lib/active_record/type/serialized.rb
+++ b/activerecord/lib/active_record/type/serialized.rb
@@ -1,6 +1,10 @@
+# frozen_string_literal: true
+
 module ActiveRecord
   module Type
     class Serialized < DelegateClass(ActiveModel::Type::Value) # :nodoc:
+      undef to_yaml if method_defined?(:to_yaml)
+
       include ActiveModel::Type::Helpers::Mutable
 
       attr_reader :subtype, :coder
@@ -43,21 +47,21 @@ module ActiveRecord
 
       def assert_valid_value(value)
         if coder.respond_to?(:assert_valid_value)
-          coder.assert_valid_value(value)
+          coder.assert_valid_value(value, action: "serialize")
         end
       end
 
       private
 
-      def default_value?(value)
-        value == coder.load(nil)
-      end
+        def default_value?(value)
+          value == coder.load(nil)
+        end
 
-      def encoded(value)
-        unless default_value?(value)
-          coder.dump(value)
+        def encoded(value)
+          unless default_value?(value)
+            coder.dump(value)
+          end
         end
-      end
     end
   end
 end
diff --git a/activerecord/lib/active_record/type/text.rb b/activerecord/lib/active_record/type/text.rb
new file mode 100644
index 0000000000..6d19696671
--- /dev/null
+++ b/activerecord/lib/active_record/type/text.rb
@@ -0,0 +1,11 @@
+# frozen_string_literal: true
+
+module ActiveRecord
+  module Type
+    class Text < ActiveModel::Type::String # :nodoc:
+      def type
+        :text
+      end
+    end
+  end
+end
diff --git a/activerecord/lib/active_record/type/time.rb b/activerecord/lib/active_record/type/time.rb
index 7da49e43c7..f4da1ecf2c 100644
--- a/activerecord/lib/active_record/type/time.rb
+++ b/activerecord/lib/active_record/type/time.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActiveRecord
   module Type
     class Time < ActiveModel::Type::Time
@@ -17,4 +19,3 @@ module ActiveRecord
     end
   end
 end
-
diff --git a/activerecord/lib/active_record/type/type_map.rb b/activerecord/lib/active_record/type/type_map.rb
index 850a7a4e09..fc40b460f0 100644
--- a/activerecord/lib/active_record/type/type_map.rb
+++ b/activerecord/lib/active_record/type/type_map.rb
@@ -1,4 +1,6 @@
-require 'concurrent/map'
+# frozen_string_literal: true
+
+require "concurrent/map"
 
 module ActiveRecord
   module Type
@@ -11,7 +13,7 @@ module ActiveRecord
       end
 
       def lookup(lookup_key, *args)
-        fetch(lookup_key, *args) { default_value }
+        fetch(lookup_key, *args) { Type.default_value }
       end
 
       def fetch(lookup_key, *args, &block)
@@ -44,21 +46,17 @@ module ActiveRecord
 
       private
 
-      def perform_fetch(lookup_key, *args)
-        matching_pair = @mapping.reverse_each.detect do |key, _|
-          key === lookup_key
-        end
+        def perform_fetch(lookup_key, *args)
+          matching_pair = @mapping.reverse_each.detect do |key, _|
+            key === lookup_key
+          end
 
-        if matching_pair
-          matching_pair.last.call(lookup_key, *args)
-        else
-          yield lookup_key, *args
+          if matching_pair
+            matching_pair.last.call(lookup_key, *args)
+          else
+            yield lookup_key, *args
+          end
         end
-      end
-
-      def default_value
-        @default_value ||= ActiveModel::Type::Value.new
-      end
     end
   end
 end
diff --git a/activerecord/lib/active_record/type/unsigned_integer.rb b/activerecord/lib/active_record/type/unsigned_integer.rb
new file mode 100644
index 0000000000..4619528f81
--- /dev/null
+++ b/activerecord/lib/active_record/type/unsigned_integer.rb
@@ -0,0 +1,17 @@
+# frozen_string_literal: true
+
+module ActiveRecord
+  module Type
+    class UnsignedInteger < ActiveModel::Type::Integer # :nodoc:
+      private
+
+        def max_value
+          super * 2
+        end
+
+        def min_value
+          0
+        end
+    end
+  end
+end
diff --git a/activerecord/lib/active_record/type_caster.rb b/activerecord/lib/active_record/type_caster.rb
index accc339d00..2e5f45fa3d 100644
--- a/activerecord/lib/active_record/type_caster.rb
+++ b/activerecord/lib/active_record/type_caster.rb
@@ -1,5 +1,7 @@
-require 'active_record/type_caster/map'
-require 'active_record/type_caster/connection'
+# frozen_string_literal: true
+
+require "active_record/type_caster/map"
+require "active_record/type_caster/connection"
 
 module ActiveRecord
   module TypeCaster # :nodoc:
diff --git a/activerecord/lib/active_record/type_caster/connection.rb b/activerecord/lib/active_record/type_caster/connection.rb
index 7ed8dcc313..af4e4e37e2 100644
--- a/activerecord/lib/active_record/type_caster/connection.rb
+++ b/activerecord/lib/active_record/type_caster/connection.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActiveRecord
   module TypeCaster
     class Connection # :nodoc:
@@ -12,18 +14,20 @@ module ActiveRecord
         connection.type_cast_from_column(column, value)
       end
 
+      # TODO Change this to private once we've dropped Ruby 2.2 support.
+      # Workaround for Ruby 2.2 "private attribute?" warning.
       protected
 
-      attr_reader :table_name
-      delegate :connection, to: :@klass
+        attr_reader :table_name
+        delegate :connection, to: :@klass
 
       private
 
-      def column_for(attribute_name)
-        if connection.schema_cache.data_source_exists?(table_name)
-          connection.schema_cache.columns_hash(table_name)[attribute_name.to_s]
+        def column_for(attribute_name)
+          if connection.schema_cache.data_source_exists?(table_name)
+            connection.schema_cache.columns_hash(table_name)[attribute_name.to_s]
+          end
         end
-      end
     end
   end
 end
diff --git a/activerecord/lib/active_record/type_caster/map.rb b/activerecord/lib/active_record/type_caster/map.rb
index 3a367b3999..d51350ba83 100644
--- a/activerecord/lib/active_record/type_caster/map.rb
+++ b/activerecord/lib/active_record/type_caster/map.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActiveRecord
   module TypeCaster
     class Map # :nodoc:
@@ -11,9 +13,11 @@ module ActiveRecord
         type.serialize(value)
       end
 
+      # TODO Change this to private once we've dropped Ruby 2.2 support.
+      # Workaround for Ruby 2.2 "private attribute?" warning.
       protected
 
-      attr_reader :types
+        attr_reader :types
     end
   end
 end
diff --git a/activerecord/lib/active_record/validations.rb b/activerecord/lib/active_record/validations.rb
index ecaf04e39e..ca27a3f0ab 100644
--- a/activerecord/lib/active_record/validations.rb
+++ b/activerecord/lib/active_record/validations.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActiveRecord
   # = Active Record \RecordInvalid
   #
@@ -40,13 +42,13 @@ module ActiveRecord
     # The validation process on save can be skipped by passing <tt>validate: false</tt>.
     # The regular {ActiveRecord::Base#save}[rdoc-ref:Persistence#save] method is replaced
     # with this when the validations module is mixed in, which it is by default.
-    def save(options={})
+    def save(options = {})
       perform_validations(options) ? super : false
     end
 
     # Attempts to save the record just like {ActiveRecord::Base#save}[rdoc-ref:Base#save] but
     # will raise an ActiveRecord::RecordInvalid exception instead of returning +false+ if the record is not valid.
-    def save!(options={})
+    def save!(options = {})
       perform_validations(options) ? super : raise_validation_error
     end
 
@@ -68,7 +70,7 @@ module ActiveRecord
 
     alias_method :validate, :valid?
 
-  protected
+  private
 
     def default_validation_context
       new_record? ? :create : :update
@@ -78,7 +80,7 @@ module ActiveRecord
       raise(RecordInvalid.new(self))
     end
 
-    def perform_validations(options={}) # :nodoc:
+    def perform_validations(options = {})
       options[:validate] == false || valid?(options[:context])
     end
   end
diff --git a/activerecord/lib/active_record/validations/absence.rb b/activerecord/lib/active_record/validations/absence.rb
index 641d041f3d..6afb9eabd2 100644
--- a/activerecord/lib/active_record/validations/absence.rb
+++ b/activerecord/lib/active_record/validations/absence.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActiveRecord
   module Validations
     class AbsenceValidator < ActiveModel::Validations::AbsenceValidator # :nodoc:
diff --git a/activerecord/lib/active_record/validations/associated.rb b/activerecord/lib/active_record/validations/associated.rb
index b14db85167..3538aeec22 100644
--- a/activerecord/lib/active_record/validations/associated.rb
+++ b/activerecord/lib/active_record/validations/associated.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActiveRecord
   module Validations
     class AssociatedValidator < ActiveModel::EachValidator #:nodoc:
@@ -37,7 +39,7 @@ module ActiveRecord
       #
       # * <tt>:message</tt> - A custom error message (default is: "is invalid").
       # * <tt>:on</tt> - Specifies the contexts where this validation is active.
-      #   Runs in all validation contexts by default (nil). You can pass a symbol
+      #   Runs in all validation contexts by default +nil+. You can pass a symbol
       #   or an array of symbols. (e.g. <tt>on: :create</tt> or
       #   <tt>on: :custom_validation_context</tt> or
       #   <tt>on: [:create, :custom_validation_context]</tt>)
diff --git a/activerecord/lib/active_record/validations/length.rb b/activerecord/lib/active_record/validations/length.rb
index 0e0cebce4a..f47b14ae3a 100644
--- a/activerecord/lib/active_record/validations/length.rb
+++ b/activerecord/lib/active_record/validations/length.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActiveRecord
   module Validations
     class LengthValidator < ActiveModel::Validations::LengthValidator # :nodoc:
diff --git a/activerecord/lib/active_record/validations/presence.rb b/activerecord/lib/active_record/validations/presence.rb
index ad82ea66c4..75e97e1997 100644
--- a/activerecord/lib/active_record/validations/presence.rb
+++ b/activerecord/lib/active_record/validations/presence.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActiveRecord
   module Validations
     class PresenceValidator < ActiveModel::Validations::PresenceValidator # :nodoc:
@@ -44,7 +46,7 @@ module ActiveRecord
       # Configuration options:
       # * <tt>:message</tt> - A custom error message (default is: "can't be blank").
       # * <tt>:on</tt> - Specifies the contexts where this validation is active.
-      #   Runs in all validation contexts by default (nil). You can pass a symbol
+      #   Runs in all validation contexts by default +nil+. You can pass a symbol
       #   or an array of symbols. (e.g. <tt>on: :create</tt> or
       #   <tt>on: :custom_validation_context</tt> or
       #   <tt>on: [:create, :custom_validation_context]</tt>)
@@ -57,7 +59,7 @@ module ActiveRecord
       #   or <tt>unless: Proc.new { |user| user.signup_step <= 2 }</tt>). The method,
       #   proc or string should return or evaluate to a +true+ or +false+ value.
       # * <tt>:strict</tt> - Specifies whether validation should be strict.
-      #   See ActiveModel::Validation#validates! for more information.
+      #   See ActiveModel::Validations#validates! for more information.
       def validates_presence_of(*attr_names)
         validates_with PresenceValidator, _merge_attributes(attr_names)
       end
diff --git a/activerecord/lib/active_record/validations/uniqueness.rb b/activerecord/lib/active_record/validations/uniqueness.rb
index ec9f498c40..4c2c5dd852 100644
--- a/activerecord/lib/active_record/validations/uniqueness.rb
+++ b/activerecord/lib/active_record/validations/uniqueness.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActiveRecord
   module Validations
     class UniquenessValidator < ActiveModel::EachValidator # :nodoc:
@@ -6,24 +8,27 @@ module ActiveRecord
           raise ArgumentError, "#{options[:conditions]} was passed as :conditions but is not callable. " \
                                "Pass a callable instead: `conditions: -> { where(approved: true) }`"
         end
+        unless Array(options[:scope]).all? { |scope| scope.respond_to?(:to_sym) }
+          raise ArgumentError, "#{options[:scope]} is not supported format for :scope option. " \
+            "Pass a symbol or an array of symbols instead: `scope: :user_id`"
+        end
         super({ case_sensitive: true }.merge!(options))
         @klass = options[:class]
       end
 
       def validate_each(record, attribute, value)
         finder_class = find_finder_class_for(record)
-        table = finder_class.arel_table
         value = map_enum_attribute(finder_class, attribute, value)
 
-        relation = build_relation(finder_class, table, attribute, value)
+        relation = build_relation(finder_class, attribute, value)
         if record.persisted?
           if finder_class.primary_key
-            relation = relation.where.not(finder_class.primary_key => record.id_was || record.id)
+            relation = relation.where.not(finder_class.primary_key => record.id_in_database || record.id)
           else
             raise UnknownPrimaryKey.new(finder_class, "Can not validate uniqueness for persisted record without primary key.")
           end
         end
-        relation = scope_relation(record, table, relation)
+        relation = scope_relation(record, relation)
         relation = relation.merge(options[:conditions]) if options[:conditions]
 
         if relation.exists?
@@ -34,13 +39,13 @@ module ActiveRecord
         end
       end
 
-    protected
+    private
       # The check for an existing value should be run from a class that
       # isn't abstract. This means working down from the current class
       # (self), to the first non-abstract class. Since classes don't know
       # their subclasses, we have to build the hierarchy between self and
       # the record's class.
-      def find_finder_class_for(record) #:nodoc:
+      def find_finder_class_for(record)
         class_hierarchy = [record.class]
 
         while class_hierarchy.first != @klass
@@ -50,43 +55,42 @@ module ActiveRecord
         class_hierarchy.detect { |klass| !klass.abstract_class? }
       end
 
-      def build_relation(klass, table, attribute, value) #:nodoc:
+      def build_relation(klass, attribute, value)
         if reflection = klass._reflect_on_association(attribute)
           attribute = reflection.foreign_key
           value = value.attributes[reflection.klass.primary_key] unless value.nil?
         end
 
+        if value.nil?
+          return klass.unscoped.where!(attribute => value)
+        end
+
         # the attribute may be an aliased attribute
         if klass.attribute_alias?(attribute)
           attribute = klass.attribute_alias(attribute)
         end
 
         attribute_name = attribute.to_s
+        value = klass.predicate_builder.build_bind_attribute(attribute_name, value)
 
+        table = klass.arel_table
         column = klass.columns_hash[attribute_name]
-        cast_type = klass.type_for_attribute(attribute_name)
 
-        comparison = if !options[:case_sensitive] && !value.nil?
+        comparison = if !options[:case_sensitive]
           # will use SQL LOWER function before comparison, unless it detects a case insensitive collation
           klass.connection.case_insensitive_comparison(table, attribute, column, value)
         else
           klass.connection.case_sensitive_comparison(table, attribute, column, value)
         end
-        if value.nil?
-          klass.unscoped.where(comparison)
-        else
-          bind = Relation::QueryAttribute.new(attribute_name, value, cast_type)
-          klass.unscoped.where(comparison, bind)
-        end
+        klass.unscoped.where!(comparison)
       end
 
-      def scope_relation(record, table, relation)
+      def scope_relation(record, relation)
         Array(options[:scope]).each do |scope_item|
-          if reflection = record.class._reflect_on_association(scope_item)
-            scope_value = record.send(reflection.foreign_key)
-            scope_item  = reflection.foreign_key
+          scope_value = if record.class._reflect_on_association(scope_item)
+            record.association(scope_item).reader
           else
-            scope_value = record._read_attribute(scope_item)
+            record._read_attribute(scope_item)
           end
           relation = relation.where(scope_item => scope_value)
         end
@@ -201,9 +205,7 @@ module ActiveRecord
       #                                      | # Boom! We now have a duplicate
       #                                      | # title!
       #
-      # This could even happen if you use transactions with the 'serializable'
-      # isolation level. The best way to work around this problem is to add a unique
-      # index to the database table using
+      # The best way to work around this problem is to add a unique index to the database table using
       # {connection.add_index}[rdoc-ref:ConnectionAdapters::SchemaStatements#add_index].
       # In the rare case that a race condition occurs, the database will guarantee
       # the field's uniqueness.
@@ -215,7 +217,7 @@ module ActiveRecord
       # can catch it and restart the transaction (e.g. by telling the user
       # that the title already exists, and asking them to re-enter the title).
       # This technique is also known as
-      # {optimistic concurrency control}[http://en.wikipedia.org/wiki/Optimistic_concurrency_control].
+      # {optimistic concurrency control}[https://en.wikipedia.org/wiki/Optimistic_concurrency_control].
       #
       # The bundled ActiveRecord::ConnectionAdapters distinguish unique index
       # constraint errors from other types of database errors by throwing an
diff --git a/activerecord/lib/active_record/version.rb b/activerecord/lib/active_record/version.rb
index cf76a13b44..6b0d82d8fc 100644
--- a/activerecord/lib/active_record/version.rb
+++ b/activerecord/lib/active_record/version.rb
@@ -1,4 +1,6 @@
-require_relative 'gem_version'
+# frozen_string_literal: true
+
+require_relative "gem_version"
 
 module ActiveRecord
   # Returns the version of the currently loaded ActiveRecord as a <tt>Gem::Version</tt>
diff --git a/activerecord/lib/rails/generators/active_record.rb b/activerecord/lib/rails/generators/active_record.rb
index dc29213235..a7e5e373a7 100644
--- a/activerecord/lib/rails/generators/active_record.rb
+++ b/activerecord/lib/rails/generators/active_record.rb
@@ -1,7 +1,9 @@
-require 'rails/generators/named_base'
-require 'rails/generators/active_model'
-require 'rails/generators/active_record/migration'
-require 'active_record'
+# frozen_string_literal: true
+
+require "rails/generators/named_base"
+require "rails/generators/active_model"
+require "rails/generators/active_record/migration"
+require "active_record"
 
 module ActiveRecord
   module Generators # :nodoc:
@@ -10,7 +12,7 @@ module ActiveRecord
 
       # Set the current directory as base for the inherited generators.
       def self.base_root
-        File.dirname(__FILE__)
+        __dir__
       end
     end
   end
diff --git a/activerecord/lib/rails/generators/active_record/application_record/application_record_generator.rb b/activerecord/lib/rails/generators/active_record/application_record/application_record_generator.rb
new file mode 100644
index 0000000000..35d5664400
--- /dev/null
+++ b/activerecord/lib/rails/generators/active_record/application_record/application_record_generator.rb
@@ -0,0 +1,27 @@
+# frozen_string_literal: true
+
+require "rails/generators/active_record"
+
+module ActiveRecord
+  module Generators # :nodoc:
+    class ApplicationRecordGenerator < ::Rails::Generators::Base # :nodoc:
+      source_root File.expand_path("templates", __dir__)
+
+      # FIXME: Change this file to a symlink once RubyGems 2.5.0 is required.
+      def create_application_record
+        template "application_record.rb", application_record_file_name
+      end
+
+      private
+
+        def application_record_file_name
+          @application_record_file_name ||=
+            if namespaced?
+              "app/models/#{namespaced_path}/application_record.rb"
+            else
+              "app/models/application_record.rb"
+            end
+        end
+    end
+  end
+end
diff --git a/activerecord/lib/rails/generators/active_record/model/templates/application_record.rb b/activerecord/lib/rails/generators/active_record/application_record/templates/application_record.rb.tt
index 60050e0bf8..60050e0bf8 100644
--- a/activerecord/lib/rails/generators/active_record/model/templates/application_record.rb
+++ b/activerecord/lib/rails/generators/active_record/application_record/templates/application_record.rb.tt
diff --git a/activerecord/lib/rails/generators/active_record/migration.rb b/activerecord/lib/rails/generators/active_record/migration.rb
index c2b2209638..4ceb502c5d 100644
--- a/activerecord/lib/rails/generators/active_record/migration.rb
+++ b/activerecord/lib/rails/generators/active_record/migration.rb
@@ -1,4 +1,6 @@
-require 'rails/generators/migration'
+# frozen_string_literal: true
+
+require "rails/generators/migration"
 
 module ActiveRecord
   module Generators # :nodoc:
@@ -20,6 +22,14 @@ module ActiveRecord
           key_type = options[:primary_key_type]
           ", id: :#{key_type}" if key_type
         end
+
+        def db_migrate_path
+          if defined?(Rails.application) && Rails.application
+            Rails.application.config.paths["db/migrate"].to_ary.first
+          else
+            "db/migrate"
+          end
+        end
     end
   end
 end
diff --git a/activerecord/lib/rails/generators/active_record/migration/migration_generator.rb b/activerecord/lib/rails/generators/active_record/migration/migration_generator.rb
index 4e5872b585..856fcc5897 100644
--- a/activerecord/lib/rails/generators/active_record/migration/migration_generator.rb
+++ b/activerecord/lib/rails/generators/active_record/migration/migration_generator.rb
@@ -1,58 +1,63 @@
-require 'rails/generators/active_record'
+# frozen_string_literal: true
+
+require "rails/generators/active_record"
 
 module ActiveRecord
   module Generators # :nodoc:
     class MigrationGenerator < Base # :nodoc:
-      argument :attributes, :type => :array, :default => [], :banner => "field[:type][:index] field[:type][:index]"
+      argument :attributes, type: :array, default: [], banner: "field[:type][:index] field[:type][:index]"
 
       class_option :primary_key_type, type: :string, desc: "The type for primary key"
 
       def create_migration_file
         set_local_assigns!
         validate_file_name!
-        migration_template @migration_template, "db/migrate/#{file_name}.rb"
+        migration_template @migration_template, File.join(db_migrate_path, "#{file_name}.rb")
       end
 
+      # TODO Change this to private once we've dropped Ruby 2.2 support.
+      # Workaround for Ruby 2.2 "private attribute?" warning.
       protected
-      attr_reader :migration_action, :join_tables
+        attr_reader :migration_action, :join_tables
+
+      private
 
-      # Sets the default migration template that is being used for the generation of the migration.
-      # Depending on command line arguments, the migration template and the table name instance
-      # variables are set up.
-      def set_local_assigns!
-        @migration_template = "migration.rb"
-        case file_name
-        when /^(add|remove)_.*_(?:to|from)_(.*)/
-          @migration_action = $1
-          @table_name       = normalize_table_name($2)
-        when /join_table/
-          if attributes.length == 2
-            @migration_action = 'join'
-            @join_tables      = pluralize_table_names? ? attributes.map(&:plural_name) : attributes.map(&:singular_name)
+        # Sets the default migration template that is being used for the generation of the migration.
+        # Depending on command line arguments, the migration template and the table name instance
+        # variables are set up.
+        def set_local_assigns!
+          @migration_template = "migration.rb"
+          case file_name
+          when /^(add)_.*_to_(.*)/, /^(remove)_.*?_from_(.*)/
+            @migration_action = $1
+            @table_name       = normalize_table_name($2)
+          when /join_table/
+            if attributes.length == 2
+              @migration_action = "join"
+              @join_tables      = pluralize_table_names? ? attributes.map(&:plural_name) : attributes.map(&:singular_name)
 
-            set_index_names
+              set_index_names
+            end
+          when /^create_(.+)/
+            @table_name = normalize_table_name($1)
+            @migration_template = "create_table_migration.rb"
           end
-        when /^create_(.+)/
-          @table_name = normalize_table_name($1)
-          @migration_template = "create_table_migration.rb"
         end
-      end
 
-      def set_index_names
-        attributes.each_with_index do |attr, i|
-          attr.index_name = [attr, attributes[i - 1]].map{ |a| index_name_for(a) }
+        def set_index_names
+          attributes.each_with_index do |attr, i|
+            attr.index_name = [attr, attributes[i - 1]].map { |a| index_name_for(a) }
+          end
         end
-      end
 
-      def index_name_for(attribute)
-        if attribute.foreign_key?
-          attribute.name
-        else
-          attribute.name.singularize.foreign_key
-        end.to_sym
-      end
+        def index_name_for(attribute)
+          if attribute.foreign_key?
+            attribute.name
+          else
+            attribute.name.singularize.foreign_key
+          end.to_sym
+        end
 
-      private
         def attributes_with_index
           attributes.select { |a| !a.reference? && a.has_index? }
         end
@@ -60,7 +65,7 @@ module ActiveRecord
         # A migration file name can only contain underscores (_), lowercase characters,
         # and numbers 0-9. Any other file name will raise an IllegalMigrationNameError.
         def validate_file_name!
-          unless file_name =~ /^[_a-z0-9]+$/
+          unless /^[_a-z0-9]+$/.match?(file_name)
             raise IllegalMigrationNameError.new(file_name)
           end
         end
diff --git a/activerecord/lib/rails/generators/active_record/migration/templates/create_table_migration.rb b/activerecord/lib/rails/generators/active_record/migration/templates/create_table_migration.rb.tt
index 5f7201cfe1..5f7201cfe1 100644
--- a/activerecord/lib/rails/generators/active_record/migration/templates/create_table_migration.rb
+++ b/activerecord/lib/rails/generators/active_record/migration/templates/create_table_migration.rb.tt
diff --git a/activerecord/lib/rails/generators/active_record/migration/templates/migration.rb b/activerecord/lib/rails/generators/active_record/migration/templates/migration.rb.tt
index 481c70201b..481c70201b 100644
--- a/activerecord/lib/rails/generators/active_record/migration/templates/migration.rb
+++ b/activerecord/lib/rails/generators/active_record/migration/templates/migration.rb.tt
diff --git a/activerecord/lib/rails/generators/active_record/model/model_generator.rb b/activerecord/lib/rails/generators/active_record/model/model_generator.rb
index 0d72913258..25e54f3ac8 100644
--- a/activerecord/lib/rails/generators/active_record/model/model_generator.rb
+++ b/activerecord/lib/rails/generators/active_record/model/model_generator.rb
@@ -1,9 +1,11 @@
-require 'rails/generators/active_record'
+# frozen_string_literal: true
+
+require "rails/generators/active_record"
 
 module ActiveRecord
   module Generators # :nodoc:
     class ModelGenerator < Base # :nodoc:
-      argument :attributes, :type => :array, :default => [], :banner => "field[:type][:index] field[:type][:index]"
+      argument :attributes, type: :array, default: [], banner: "field[:type][:index] field[:type][:index]"
 
       check_class_collision
 
@@ -17,52 +19,29 @@ module ActiveRecord
       def create_migration_file
         return unless options[:migration] && options[:parent].nil?
         attributes.each { |a| a.attr_options.delete(:index) if a.reference? && !a.has_index? } if options[:indexes] == false
-        migration_template "../../migration/templates/create_table_migration.rb", "db/migrate/create_#{table_name}.rb"
+        migration_template "../../migration/templates/create_table_migration.rb", File.join(db_migrate_path, "create_#{table_name}.rb")
       end
 
       def create_model_file
-        generate_application_record
-        template 'model.rb', File.join('app/models', class_path, "#{file_name}.rb")
+        template "model.rb", File.join("app/models", class_path, "#{file_name}.rb")
       end
 
       def create_module_file
         return if regular_class_path.empty?
-        generate_application_record
-        template 'module.rb', File.join('app/models', "#{class_path.join('/')}.rb") if behavior == :invoke
+        template "module.rb", File.join("app/models", "#{class_path.join('/')}.rb") if behavior == :invoke
       end
 
       hook_for :test_framework
 
-      protected
+      private
 
         def attributes_with_index
           attributes.select { |a| !a.reference? && a.has_index? }
         end
 
-        # FIXME: Change this file to a symlink once RubyGems 2.5.0 is required.
-        def generate_application_record
-          if self.behavior == :invoke && !application_record_exist?
-            template 'application_record.rb', application_record_file_name
-          end
-        end
-
         # Used by the migration template to determine the parent name of the model
         def parent_class_name
-          options[:parent] || 'ApplicationRecord'
-        end
-
-        def application_record_exist?
-          file_exist = nil
-          in_root { file_exist = File.exist?(application_record_file_name) }
-          file_exist
-        end
-
-        def application_record_file_name
-          @application_record_file_name ||= if mountable_engine?
-            "app/models/#{namespaced_path}/application_record.rb"
-          else
-            'app/models/application_record.rb'
-          end
+          options[:parent] || "ApplicationRecord"
         end
     end
   end
diff --git a/activerecord/lib/rails/generators/active_record/model/templates/model.rb b/activerecord/lib/rails/generators/active_record/model/templates/model.rb.tt
index 55dc65c8ad..55dc65c8ad 100644
--- a/activerecord/lib/rails/generators/active_record/model/templates/model.rb
+++ b/activerecord/lib/rails/generators/active_record/model/templates/model.rb.tt
diff --git a/activerecord/lib/rails/generators/active_record/model/templates/module.rb b/activerecord/lib/rails/generators/active_record/model/templates/module.rb.tt
index a3bf1c37b6..a3bf1c37b6 100644
--- a/activerecord/lib/rails/generators/active_record/model/templates/module.rb
+++ b/activerecord/lib/rails/generators/active_record/model/templates/module.rb.tt
diff --git a/activerecord/test/active_record/connection_adapters/fake_adapter.rb b/activerecord/test/active_record/connection_adapters/fake_adapter.rb
index 43c817e057..f977b2997b 100644
--- a/activerecord/test/active_record/connection_adapters/fake_adapter.rb
+++ b/activerecord/test/active_record/connection_adapters/fake_adapter.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActiveRecord
   module ConnectionHandling
     def fake_connection(config)
@@ -9,7 +11,7 @@ module ActiveRecord
     class FakeAdapter < AbstractAdapter
       attr_accessor :data_sources, :primary_keys
 
-      @columns = Hash.new { |h,k| h[k] = [] }
+      @columns = Hash.new { |h, k| h[k] = [] }
       class << self
         attr_reader :columns
       end
diff --git a/activerecord/test/assets/schema_dump_5_1.yml b/activerecord/test/assets/schema_dump_5_1.yml
new file mode 100644
index 0000000000..f37977daf2
--- /dev/null
+++ b/activerecord/test/assets/schema_dump_5_1.yml
@@ -0,0 +1,345 @@
+--- !ruby/object:ActiveRecord::ConnectionAdapters::SchemaCache
+columns:
+  posts:
+  - &1 !ruby/object:ActiveRecord::ConnectionAdapters::Column
+    name: id
+    table_name: posts
+    sql_type_metadata: !ruby/object:ActiveRecord::ConnectionAdapters::SqlTypeMetadata
+      sql_type: INTEGER
+      type: :integer
+      limit: 
+      precision: 
+      scale: 
+    'null': false
+    default: 
+    default_function: 
+    collation: 
+    comment: 
+  - &2 !ruby/object:ActiveRecord::ConnectionAdapters::Column
+    name: author_id
+    table_name: posts
+    sql_type_metadata: !ruby/object:ActiveRecord::ConnectionAdapters::SqlTypeMetadata
+      sql_type: integer
+      type: :integer
+      limit: 
+      precision: 
+      scale: 
+    'null': true
+    default: 
+    default_function: 
+    collation: 
+    comment: 
+  - &3 !ruby/object:ActiveRecord::ConnectionAdapters::Column
+    name: title
+    table_name: posts
+    sql_type_metadata: !ruby/object:ActiveRecord::ConnectionAdapters::SqlTypeMetadata
+      sql_type: varchar
+      type: :string
+      limit: 
+      precision: 
+      scale: 
+    'null': false
+    default: 
+    default_function: 
+    collation: 
+    comment: 
+  - &4 !ruby/object:ActiveRecord::ConnectionAdapters::Column
+    name: body
+    table_name: posts
+    sql_type_metadata: !ruby/object:ActiveRecord::ConnectionAdapters::SqlTypeMetadata
+      sql_type: text
+      type: :text
+      limit: 
+      precision: 
+      scale: 
+    'null': false
+    default: 
+    default_function: 
+    collation: 
+    comment: 
+  - &5 !ruby/object:ActiveRecord::ConnectionAdapters::Column
+    name: type
+    table_name: posts
+    sql_type_metadata: !ruby/object:ActiveRecord::ConnectionAdapters::SqlTypeMetadata
+      sql_type: varchar
+      type: :string
+      limit: 
+      precision: 
+      scale: 
+    'null': true
+    default: 
+    default_function: 
+    collation: 
+    comment: 
+  - &6 !ruby/object:ActiveRecord::ConnectionAdapters::Column
+    name: comments_count
+    table_name: posts
+    sql_type_metadata: !ruby/object:ActiveRecord::ConnectionAdapters::SqlTypeMetadata
+      sql_type: integer
+      type: :integer
+      limit: 
+      precision: 
+      scale: 
+    'null': true
+    default: '0'
+    default_function: 
+    collation: 
+    comment: 
+  - &7 !ruby/object:ActiveRecord::ConnectionAdapters::Column
+    name: taggings_with_delete_all_count
+    table_name: posts
+    sql_type_metadata: !ruby/object:ActiveRecord::ConnectionAdapters::SqlTypeMetadata
+      sql_type: integer
+      type: :integer
+      limit: 
+      precision: 
+      scale: 
+    'null': true
+    default: '0'
+    default_function: 
+    collation: 
+    comment: 
+  - &8 !ruby/object:ActiveRecord::ConnectionAdapters::Column
+    name: taggings_with_destroy_count
+    table_name: posts
+    sql_type_metadata: !ruby/object:ActiveRecord::ConnectionAdapters::SqlTypeMetadata
+      sql_type: integer
+      type: :integer
+      limit: 
+      precision: 
+      scale: 
+    'null': true
+    default: '0'
+    default_function: 
+    collation: 
+    comment: 
+  - &9 !ruby/object:ActiveRecord::ConnectionAdapters::Column
+    name: tags_count
+    table_name: posts
+    sql_type_metadata: !ruby/object:ActiveRecord::ConnectionAdapters::SqlTypeMetadata
+      sql_type: integer
+      type: :integer
+      limit: 
+      precision: 
+      scale: 
+    'null': true
+    default: '0'
+    default_function: 
+    collation: 
+    comment: 
+  - &10 !ruby/object:ActiveRecord::ConnectionAdapters::Column
+    name: tags_with_destroy_count
+    table_name: posts
+    sql_type_metadata: !ruby/object:ActiveRecord::ConnectionAdapters::SqlTypeMetadata
+      sql_type: integer
+      type: :integer
+      limit: 
+      precision: 
+      scale: 
+    'null': true
+    default: '0'
+    default_function: 
+    collation: 
+    comment: 
+  - &11 !ruby/object:ActiveRecord::ConnectionAdapters::Column
+    name: tags_with_nullify_count
+    table_name: posts
+    sql_type_metadata: !ruby/object:ActiveRecord::ConnectionAdapters::SqlTypeMetadata
+      sql_type: integer
+      type: :integer
+      limit: 
+      precision: 
+      scale: 
+    'null': true
+    default: '0'
+    default_function: 
+    collation: 
+    comment: 
+columns_hash:
+  posts:
+    id: *1
+    author_id: *2
+    title: *3
+    body: *4
+    type: *5
+    comments_count: *6
+    taggings_with_delete_all_count: *7
+    taggings_with_destroy_count: *8
+    tags_count: *9
+    tags_with_destroy_count: *10
+    tags_with_nullify_count: *11
+primary_keys:
+  posts: id
+data_sources:
+  ar_internal_metadata: true
+  table_with_autoincrement: true
+  accounts: true
+  admin_accounts: true
+  admin_users: true
+  aircraft: true
+  articles: true
+  articles_magazines: true
+  articles_tags: true
+  audit_logs: true
+  authors: true
+  author_addresses: true
+  author_favorites: true
+  auto_id_tests: true
+  binaries: true
+  birds: true
+  books: true
+  booleans: true
+  bulbs: true
+  CamelCase: true
+  cars: true
+  carriers: true
+  categories: true
+  categories_posts: true
+  categorizations: true
+  citations: true
+  clubs: true
+  collections: true
+  colnametests: true
+  columns: true
+  comments: true
+  companies: true
+  content: true
+  content_positions: true
+  vegetables: true
+  computers: true
+  computers_developers: true
+  contracts: true
+  customers: true
+  customer_carriers: true
+  dashboards: true
+  developers: true
+  developers_projects: true
+  dog_lovers: true
+  dogs: true
+  doubloons: true
+  edges: true
+  engines: true
+  entrants: true
+  essays: true
+  events: true
+  eyes: true
+  funny_jokes: true
+  cold_jokes: true
+  friendships: true
+  goofy_string_id: true
+  having: true
+  guids: true
+  guitars: true
+  inept_wizards: true
+  integer_limits: true
+  invoices: true
+  iris: true
+  items: true
+  jobs: true
+  jobs_pool: true
+  keyboards: true
+  legacy_things: true
+  lessons: true
+  lessons_students: true
+  students: true
+  lint_models: true
+  line_items: true
+  lions: true
+  lock_without_defaults: true
+  lock_without_defaults_cust: true
+  magazines: true
+  mateys: true
+  members: true
+  member_details: true
+  member_friends: true
+  memberships: true
+  member_types: true
+  mentors: true
+  minivans: true
+  minimalistics: true
+  mixed_case_monkeys: true
+  mixins: true
+  movies: true
+  notifications: true
+  numeric_data: true
+  orders: true
+  organizations: true
+  owners: true
+  paint_colors: true
+  paint_textures: true
+  parrots: true
+  parrots_pirates: true
+  parrots_treasures: true
+  people: true
+  peoples_treasures: true
+  personal_legacy_things: true
+  pets: true
+  pets_treasures: true
+  pirates: true
+  posts: true
+  serialized_posts: true
+  images: true
+  price_estimates: true
+  products: true
+  product_types: true
+  projects: true
+  randomly_named_table1: true
+  randomly_named_table2: true
+  randomly_named_table3: true
+  ratings: true
+  readers: true
+  references: true
+  shape_expressions: true
+  ships: true
+  ship_parts: true
+  prisoners: true
+  shop_accounts: true
+  speedometers: true
+  sponsors: true
+  string_key_objects: true
+  subscribers: true
+  subscriptions: true
+  tags: true
+  taggings: true
+  tasks: true
+  topics: true
+  toys: true
+  traffic_lights: true
+  treasures: true
+  tuning_pegs: true
+  tyres: true
+  variants: true
+  vertices: true
+  warehouse-things: true
+  circles: true
+  squares: true
+  triangles: true
+  non_poly_ones: true
+  non_poly_twos: true
+  men: true
+  faces: true
+  interests: true
+  zines: true
+  wheels: true
+  countries: true
+  treaties: true
+  countries_treaties: true
+  liquid: true
+  molecules: true
+  electrons: true
+  weirds: true
+  nodes: true
+  trees: true
+  hotels: true
+  departments: true
+  cake_designers: true
+  drink_designers: true
+  chefs: true
+  recipes: true
+  records: true
+  overloaded_types: true
+  users: true
+  test_with_keyword_column_name: true
+  fk_test_has_pk: true
+  fk_test_has_fk: true
+version: 0
diff --git a/activerecord/test/cases/adapter_test.rb b/activerecord/test/cases/adapter_test.rb
index 34e3bc9d66..9aaa2852d0 100644
--- a/activerecord/test/cases/adapter_test.rb
+++ b/activerecord/test/cases/adapter_test.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require "cases/helper"
 require "models/book"
 require "models/post"
@@ -30,101 +32,102 @@ module ActiveRecord
       assert_nothing_raised { Book.destroy(0) }
     end
 
-    def test_tables
-      tables = nil
-      ActiveSupport::Deprecation.silence { tables = @connection.tables }
-      assert tables.include?("accounts")
-      assert tables.include?("authors")
-      assert tables.include?("tasks")
-      assert tables.include?("topics")
+    def test_valid_column
+      @connection.native_database_types.each_key do |type|
+        assert @connection.valid_type?(type)
+      end
     end
 
-    def test_table_exists?
-      ActiveSupport::Deprecation.silence do
-        assert @connection.table_exists?("accounts")
-        assert !@connection.table_exists?("nonexistingtable")
-        assert !@connection.table_exists?(nil)
-      end
+    def test_invalid_column
+      assert_not @connection.valid_type?(:foobar)
     end
 
-    def test_table_exists_checking_both_tables_and_views_is_deprecated
-      assert_deprecated { @connection.table_exists?("accounts") }
+    def test_tables
+      tables = @connection.tables
+      assert_includes tables, "accounts"
+      assert_includes tables, "authors"
+      assert_includes tables, "tasks"
+      assert_includes tables, "topics"
+    end
+
+    def test_table_exists?
+      assert @connection.table_exists?("accounts")
+      assert @connection.table_exists?(:accounts)
+      assert_not @connection.table_exists?("nonexistingtable")
+      assert_not @connection.table_exists?("'")
+      assert_not @connection.table_exists?(nil)
     end
 
     def test_data_sources
       data_sources = @connection.data_sources
-      assert data_sources.include?("accounts")
-      assert data_sources.include?("authors")
-      assert data_sources.include?("tasks")
-      assert data_sources.include?("topics")
+      assert_includes data_sources, "accounts"
+      assert_includes data_sources, "authors"
+      assert_includes data_sources, "tasks"
+      assert_includes data_sources, "topics"
     end
 
     def test_data_source_exists?
       assert @connection.data_source_exists?("accounts")
       assert @connection.data_source_exists?(:accounts)
       assert_not @connection.data_source_exists?("nonexistingtable")
+      assert_not @connection.data_source_exists?("'")
       assert_not @connection.data_source_exists?(nil)
     end
 
     def test_indexes
       idx_name = "accounts_idx"
 
-      if @connection.respond_to?(:indexes)
-        indexes = @connection.indexes("accounts")
-        assert indexes.empty?
-
-        @connection.add_index :accounts, :firm_id, :name => idx_name
-        indexes = @connection.indexes("accounts")
-        assert_equal "accounts", indexes.first.table
-        assert_equal idx_name, indexes.first.name
-        assert !indexes.first.unique
-        assert_equal ["firm_id"], indexes.first.columns
-      else
-        warn "#{@connection.class} does not respond to #indexes"
-      end
+      indexes = @connection.indexes("accounts")
+      assert indexes.empty?
 
+      @connection.add_index :accounts, :firm_id, name: idx_name
+      indexes = @connection.indexes("accounts")
+      assert_equal "accounts", indexes.first.table
+      assert_equal idx_name, indexes.first.name
+      assert !indexes.first.unique
+      assert_equal ["firm_id"], indexes.first.columns
     ensure
-      @connection.remove_index(:accounts, :name => idx_name) rescue nil
+      @connection.remove_index(:accounts, name: idx_name) rescue nil
     end
 
     def test_remove_index_when_name_and_wrong_column_name_specified
       index_name = "accounts_idx"
 
-      @connection.add_index :accounts, :firm_id, :name => index_name
+      @connection.add_index :accounts, :firm_id, name: index_name
       assert_raises ArgumentError do
-        @connection.remove_index :accounts, :name => index_name, :column => :wrong_column_name
+        @connection.remove_index :accounts, name: index_name, column: :wrong_column_name
       end
     ensure
-      @connection.remove_index(:accounts, :name => index_name)
+      @connection.remove_index(:accounts, name: index_name)
     end
 
     def test_current_database
       if @connection.respond_to?(:current_database)
-        assert_equal ARTest.connection_config['arunit']['database'], @connection.current_database
+        assert_equal ARTest.connection_config["arunit"]["database"], @connection.current_database
       end
     end
 
     if current_adapter?(:Mysql2Adapter)
       def test_charset
         assert_not_nil @connection.charset
-        assert_not_equal 'character_set_database', @connection.charset
-        assert_equal @connection.show_variable('character_set_database'), @connection.charset
+        assert_not_equal "character_set_database", @connection.charset
+        assert_equal @connection.show_variable("character_set_database"), @connection.charset
       end
 
       def test_collation
         assert_not_nil @connection.collation
-        assert_not_equal 'collation_database', @connection.collation
-        assert_equal @connection.show_variable('collation_database'), @connection.collation
+        assert_not_equal "collation_database", @connection.collation
+        assert_equal @connection.show_variable("collation_database"), @connection.collation
       end
 
       def test_show_nonexistent_variable_returns_nil
-        assert_nil @connection.show_variable('foo_bar_baz')
+        assert_nil @connection.show_variable("foo_bar_baz")
       end
 
       def test_not_specifying_database_name_for_cross_database_selects
         begin
           assert_nothing_raised do
-            ActiveRecord::Base.establish_connection(ActiveRecord::Base.configurations['arunit'].except(:database))
+            ActiveRecord::Base.establish_connection(ActiveRecord::Base.configurations["arunit"].except(:database))
 
             config = ARTest.connection_config
             ActiveRecord::Base.connection.execute(
@@ -145,9 +148,9 @@ module ActiveRecord
         alias_method :table_alias_length,     :test_table_alias_length
       end
 
-      assert_equal 'posts',      @connection.table_alias_for('posts')
-      assert_equal 'posts_comm', @connection.table_alias_for('posts_comments')
-      assert_equal 'dbo_posts',  @connection.table_alias_for('dbo.posts')
+      assert_equal "posts",      @connection.table_alias_for("posts")
+      assert_equal "posts_comm", @connection.table_alias_for("posts_comments")
+      assert_equal "dbo_posts",  @connection.table_alias_for("dbo.posts")
 
       class << @connection
         remove_method :table_alias_length
@@ -155,26 +158,6 @@ module ActiveRecord
       end
     end
 
-    # test resetting sequences in odd tables in PostgreSQL
-    if ActiveRecord::Base.connection.respond_to?(:reset_pk_sequence!)
-      require 'models/movie'
-      require 'models/subscriber'
-
-      def test_reset_empty_table_with_custom_pk
-        Movie.delete_all
-        Movie.connection.reset_pk_sequence! 'movies'
-        assert_equal 1, Movie.create(:name => 'fight club').id
-      end
-
-      def test_reset_table_with_non_integer_pk
-        Subscriber.delete_all
-        Subscriber.connection.reset_pk_sequence! 'subscribers'
-        sub = Subscriber.new(:name => 'robert drake')
-        sub.id = 'bob drake'
-        assert_nothing_raised { sub.save! }
-      end
-    end
-
     def test_uniqueness_violations_are_translated_to_specific_exception
       @connection.execute "INSERT INTO subscribers(nick) VALUES('me')"
       error = assert_raises(ActiveRecord::RecordNotUnique) do
@@ -184,59 +167,52 @@ module ActiveRecord
       assert_not_nil error.cause
     end
 
-    unless current_adapter?(:SQLite3Adapter)
-      def test_foreign_key_violations_are_translated_to_specific_exception
-        error = assert_raises(ActiveRecord::InvalidForeignKey) do
-          # Oracle adapter uses prefetched primary key values from sequence and passes them to connection adapter insert method
-          if @connection.prefetch_primary_key?
-            id_value = @connection.next_sequence_value(@connection.default_sequence_name("fk_test_has_fk", "id"))
-            @connection.execute "INSERT INTO fk_test_has_fk (id, fk_id) VALUES (#{id_value},0)"
-          else
-            @connection.execute "INSERT INTO fk_test_has_fk (fk_id) VALUES (0)"
-          end
-        end
-
-        assert_not_nil error.cause
+    def test_not_null_violations_are_translated_to_specific_exception
+      error = assert_raises(ActiveRecord::NotNullViolation) do
+        Post.create
       end
 
-      def test_foreign_key_violations_are_translated_to_specific_exception_with_validate_false
-        klass_has_fk = Class.new(ActiveRecord::Base) do
-          self.table_name = 'fk_test_has_fk'
-        end
+      assert_not_nil error.cause
+    end
 
-        error = assert_raises(ActiveRecord::InvalidForeignKey) do
-          has_fk = klass_has_fk.new
-          has_fk.fk_id = 1231231231
-          has_fk.save(validate: false)
+    unless current_adapter?(:SQLite3Adapter)
+      def test_value_limit_violations_are_translated_to_specific_exception
+        error = assert_raises(ActiveRecord::ValueTooLong) do
+          Event.create(title: "abcdefgh")
         end
 
         assert_not_nil error.cause
       end
 
-      def test_value_limit_violations_are_translated_to_specific_exception
-        error = assert_raises(ActiveRecord::ValueTooLong) do
-          Event.create(title: 'abcdefgh')
+      def test_numeric_value_out_of_ranges_are_translated_to_specific_exception
+        error = assert_raises(ActiveRecord::RangeError) do
+          Book.connection.create("INSERT INTO books(author_id) VALUES (9223372036854775808)")
         end
 
         assert_not_nil error.cause
       end
     end
 
-    def test_disable_referential_integrity
-      assert_nothing_raised do
-        @connection.disable_referential_integrity do
-          # Oracle adapter uses prefetched primary key values from sequence and passes them to connection adapter insert method
-          if @connection.prefetch_primary_key?
-            id_value = @connection.next_sequence_value(@connection.default_sequence_name("fk_test_has_fk", "id"))
-            @connection.execute "INSERT INTO fk_test_has_fk (id, fk_id) VALUES (#{id_value},0)"
-          else
-            @connection.execute "INSERT INTO fk_test_has_fk (fk_id) VALUES (0)"
-          end
-          # should delete created record as otherwise disable_referential_integrity will try to enable constraints after executed block
-          # and will fail (at least on Oracle)
-          @connection.execute "DELETE FROM fk_test_has_fk"
-        end
+    def test_exceptions_from_notifications_are_not_translated
+      original_error = StandardError.new("This StandardError shouldn't get translated")
+      subscriber = ActiveSupport::Notifications.subscribe("sql.active_record") { raise original_error }
+      actual_error = assert_raises(StandardError) do
+        @connection.execute("SELECT * FROM posts")
+      end
+
+      assert_equal original_error, actual_error
+
+    ensure
+      ActiveSupport::Notifications.unsubscribe(subscriber) if subscriber
+    end
+
+    def test_database_related_exceptions_are_translated_to_statement_invalid
+      error = assert_raises(ActiveRecord::StatementInvalid) do
+        @connection.execute("This is a syntax error")
       end
+
+      assert_instance_of ActiveRecord::StatementInvalid, error
+      assert_kind_of Exception, error.cause
     end
 
     def test_select_all_always_return_activerecord_result
@@ -244,22 +220,61 @@ module ActiveRecord
       assert result.is_a?(ActiveRecord::Result)
     end
 
+    if ActiveRecord::Base.connection.prepared_statements
+      def test_select_all_with_legacy_binds
+        post = Post.create!(title: "foo", body: "bar")
+        expected = @connection.select_all("SELECT * FROM posts WHERE id = #{post.id}")
+        result = @connection.select_all("SELECT * FROM posts WHERE id = #{Arel::Nodes::BindParam.new(nil).to_sql}", nil, [[nil, post.id]])
+        assert_equal expected.to_hash, result.to_hash
+      end
+
+      def test_insert_update_delete_with_legacy_binds
+        binds = [[nil, 1]]
+        bind_param = Arel::Nodes::BindParam.new(nil)
+
+        id = @connection.insert("INSERT INTO events(id) VALUES (#{bind_param.to_sql})", nil, nil, nil, nil, binds)
+        assert_equal 1, id
+
+        @connection.update("UPDATE events SET title = 'foo' WHERE id = #{bind_param.to_sql}", nil, binds)
+        result = @connection.select_all("SELECT * FROM events WHERE id = #{bind_param.to_sql}", nil, binds)
+        assert_equal({ "id" => 1, "title" => "foo" }, result.first)
+
+        @connection.delete("DELETE FROM events WHERE id = #{bind_param.to_sql}", nil, binds)
+        result = @connection.select_all("SELECT * FROM events WHERE id = #{bind_param.to_sql}", nil, binds)
+        assert_nil result.first
+      end
+
+      def test_insert_update_delete_with_binds
+        binds = [Relation::QueryAttribute.new("id", 1, Type.default_value)]
+        bind_param = Arel::Nodes::BindParam.new(nil)
+
+        id = @connection.insert("INSERT INTO events(id) VALUES (#{bind_param.to_sql})", nil, nil, nil, nil, binds)
+        assert_equal 1, id
+
+        @connection.update("UPDATE events SET title = 'foo' WHERE id = #{bind_param.to_sql}", nil, binds)
+        result = @connection.select_all("SELECT * FROM events WHERE id = #{bind_param.to_sql}", nil, binds)
+        assert_equal({ "id" => 1, "title" => "foo" }, result.first)
+
+        @connection.delete("DELETE FROM events WHERE id = #{bind_param.to_sql}", nil, binds)
+        result = @connection.select_all("SELECT * FROM events WHERE id = #{bind_param.to_sql}", nil, binds)
+        assert_nil result.first
+      end
+    end
+
     def test_select_methods_passing_a_association_relation
-      author = Author.create!(name: 'john')
-      Post.create!(author: author, title: 'foo', body: 'bar')
-      query = author.posts.where(title: 'foo').select(:title)
-      assert_equal({"title" => "foo"}, @connection.select_one(query.arel, nil, query.bound_attributes))
-      assert_equal({"title" => "foo"}, @connection.select_one(query))
+      author = Author.create!(name: "john")
+      Post.create!(author: author, title: "foo", body: "bar")
+      query = author.posts.where(title: "foo").select(:title)
+      assert_equal({ "title" => "foo" }, @connection.select_one(query))
       assert @connection.select_all(query).is_a?(ActiveRecord::Result)
       assert_equal "foo", @connection.select_value(query)
       assert_equal ["foo"], @connection.select_values(query)
     end
 
     def test_select_methods_passing_a_relation
-      Post.create!(title: 'foo', body: 'bar')
-      query = Post.where(title: 'foo').select(:title)
-      assert_equal({"title" => "foo"}, @connection.select_one(query.arel, nil, query.bound_attributes))
-      assert_equal({"title" => "foo"}, @connection.select_one(query))
+      Post.create!(title: "foo", body: "bar")
+      query = Post.where(title: "foo").select(:title)
+      assert_equal({ "title" => "foo" }, @connection.select_one(query))
       assert @connection.select_all(query).is_a?(ActiveRecord::Result)
       assert_equal "foo", @connection.select_value(query)
       assert_equal ["foo"], @connection.select_values(query)
@@ -271,25 +286,68 @@ module ActiveRecord
 
     unless current_adapter?(:PostgreSQLAdapter)
       def test_log_invalid_encoding
-        error = assert_raise ActiveRecord::StatementInvalid do
+        error = assert_raises RuntimeError do
           @connection.send :log, "SELECT 'ы' FROM DUAL" do
-            raise 'ы'.force_encoding(Encoding::ASCII_8BIT)
+            raise "ы".dup.force_encoding(Encoding::ASCII_8BIT)
           end
         end
 
-        assert_not_nil error.cause
+        assert_equal "ы", error.message
       end
     end
+  end
+
+  class AdapterForeignKeyTest < ActiveRecord::TestCase
+    self.use_transactional_tests = false
+
+    def setup
+      @connection = ActiveRecord::Base.connection
+    end
 
-    if current_adapter?(:Mysql2Adapter, :SQLite3Adapter)
-      def test_tables_returning_both_tables_and_views_is_deprecated
-        assert_deprecated { @connection.tables }
+    def test_foreign_key_violations_are_translated_to_specific_exception_with_validate_false
+      klass_has_fk = Class.new(ActiveRecord::Base) do
+        self.table_name = "fk_test_has_fk"
       end
+
+      error = assert_raises(ActiveRecord::InvalidForeignKey) do
+        has_fk = klass_has_fk.new
+        has_fk.fk_id = 1231231231
+        has_fk.save(validate: false)
+      end
+
+      assert_not_nil error.cause
     end
 
-    def test_passing_arguments_to_tables_is_deprecated
-      assert_deprecated { @connection.tables(:books) }
+    def test_foreign_key_violations_are_translated_to_specific_exception
+      error = assert_raises(ActiveRecord::InvalidForeignKey) do
+        insert_into_fk_test_has_fk
+      end
+
+      assert_not_nil error.cause
     end
+
+    def test_disable_referential_integrity
+      assert_nothing_raised do
+        @connection.disable_referential_integrity do
+          insert_into_fk_test_has_fk
+          # should delete created record as otherwise disable_referential_integrity will try to enable constraints
+          # after executed block and will fail (at least on Oracle)
+          @connection.execute "DELETE FROM fk_test_has_fk"
+        end
+      end
+    end
+
+    private
+
+      def insert_into_fk_test_has_fk
+        # Oracle adapter uses prefetched primary key values from sequence and passes them to connection adapter insert method
+        if @connection.prefetch_primary_key?
+          id_value = @connection.next_sequence_value(@connection.default_sequence_name("fk_test_has_fk", "id"))
+          @connection.execute "INSERT INTO fk_test_has_fk (id,fk_id) VALUES (#{id_value},0)"
+        else
+          @connection.execute "INSERT INTO fk_test_has_fk (fk_id) VALUES (0)"
+        end
+      end
   end
 
   class AdapterTestWithoutTransaction < ActiveRecord::TestCase
@@ -322,5 +380,25 @@ module ActiveRecord
         assert !@connection.transaction_open?
       end
     end
+
+    # test resetting sequences in odd tables in PostgreSQL
+    if ActiveRecord::Base.connection.respond_to?(:reset_pk_sequence!)
+      require "models/movie"
+      require "models/subscriber"
+
+      def test_reset_empty_table_with_custom_pk
+        Movie.delete_all
+        Movie.connection.reset_pk_sequence! "movies"
+        assert_equal 1, Movie.create(name: "fight club").id
+      end
+
+      def test_reset_table_with_non_integer_pk
+        Subscriber.delete_all
+        Subscriber.connection.reset_pk_sequence! "subscribers"
+        sub = Subscriber.new(name: "robert drake")
+        sub.id = "bob drake"
+        assert_nothing_raised { sub.save! }
+      end
+    end
   end
 end
diff --git a/activerecord/test/cases/adapters/mysql2/active_schema_test.rb b/activerecord/test/cases/adapters/mysql2/active_schema_test.rb
index 95d1f6b8a3..6931b085a8 100644
--- a/activerecord/test/cases/adapters/mysql2/active_schema_test.rb
+++ b/activerecord/test/cases/adapters/mysql2/active_schema_test.rb
@@ -1,5 +1,7 @@
+# frozen_string_literal: true
+
 require "cases/helper"
-require 'support/connection_helper'
+require "support/connection_helper"
 
 class Mysql2ActiveSchemaTest < ActiveRecord::Mysql2TestCase
   include ConnectionHelper
@@ -7,7 +9,7 @@ class Mysql2ActiveSchemaTest < ActiveRecord::Mysql2TestCase
   def setup
     ActiveRecord::Base.connection.singleton_class.class_eval do
       alias_method :execute_without_stub, :execute
-      def execute(sql, name = nil) return sql end
+      def execute(sql, name = nil) sql end
     end
   end
 
@@ -21,56 +23,59 @@ class Mysql2ActiveSchemaTest < ActiveRecord::Mysql2TestCase
     def (ActiveRecord::Base.connection).index_name_exists?(*); false; end
 
     expected = "CREATE  INDEX `index_people_on_last_name`  ON `people` (`last_name`) "
-    assert_equal expected, add_index(:people, :last_name, :length => nil)
+    assert_equal expected, add_index(:people, :last_name, length: nil)
 
     expected = "CREATE  INDEX `index_people_on_last_name`  ON `people` (`last_name`(10)) "
-    assert_equal expected, add_index(:people, :last_name, :length => 10)
+    assert_equal expected, add_index(:people, :last_name, length: 10)
 
     expected = "CREATE  INDEX `index_people_on_last_name_and_first_name`  ON `people` (`last_name`(15), `first_name`(15)) "
-    assert_equal expected, add_index(:people, [:last_name, :first_name], :length => 15)
+    assert_equal expected, add_index(:people, [:last_name, :first_name], length: 15)
+    assert_equal expected, add_index(:people, ["last_name", "first_name"], length: 15)
 
     expected = "CREATE  INDEX `index_people_on_last_name_and_first_name`  ON `people` (`last_name`(15), `first_name`) "
-    assert_equal expected, add_index(:people, [:last_name, :first_name], :length => {:last_name => 15})
+    assert_equal expected, add_index(:people, [:last_name, :first_name], length: { last_name: 15 })
+    assert_equal expected, add_index(:people, ["last_name", "first_name"], length: { last_name: 15 })
 
     expected = "CREATE  INDEX `index_people_on_last_name_and_first_name`  ON `people` (`last_name`(15), `first_name`(10)) "
-    assert_equal expected, add_index(:people, [:last_name, :first_name], :length => {:last_name => 15, :first_name => 10})
+    assert_equal expected, add_index(:people, [:last_name, :first_name], length: { last_name: 15, first_name: 10 })
+    assert_equal expected, add_index(:people, ["last_name", :first_name], length: { last_name: 15, "first_name" => 10 })
 
     %w(SPATIAL FULLTEXT UNIQUE).each do |type|
       expected = "CREATE #{type} INDEX `index_people_on_last_name`  ON `people` (`last_name`) "
-      assert_equal expected, add_index(:people, :last_name, :type => type)
+      assert_equal expected, add_index(:people, :last_name, type: type)
     end
 
     %w(btree hash).each do |using|
       expected = "CREATE  INDEX `index_people_on_last_name` USING #{using} ON `people` (`last_name`) "
-      assert_equal expected, add_index(:people, :last_name, :using => using)
+      assert_equal expected, add_index(:people, :last_name, using: using)
     end
 
     expected = "CREATE  INDEX `index_people_on_last_name` USING btree ON `people` (`last_name`(10)) "
-    assert_equal expected, add_index(:people, :last_name, :length => 10, :using => :btree)
+    assert_equal expected, add_index(:people, :last_name, length: 10, using: :btree)
 
     expected = "CREATE  INDEX `index_people_on_last_name` USING btree ON `people` (`last_name`(10)) ALGORITHM = COPY"
-    assert_equal expected, add_index(:people, :last_name, :length => 10, using: :btree, algorithm: :copy)
+    assert_equal expected, add_index(:people, :last_name, length: 10, using: :btree, algorithm: :copy)
 
     assert_raise ArgumentError do
       add_index(:people, :last_name, algorithm: :coyp)
     end
 
     expected = "CREATE  INDEX `index_people_on_last_name_and_first_name` USING btree ON `people` (`last_name`(15), `first_name`(15)) "
-    assert_equal expected, add_index(:people, [:last_name, :first_name], :length => 15, :using => :btree)
+    assert_equal expected, add_index(:people, [:last_name, :first_name], length: 15, using: :btree)
   end
 
   def test_index_in_create
     def (ActiveRecord::Base.connection).data_source_exists?(*); false; end
 
     %w(SPATIAL FULLTEXT UNIQUE).each do |type|
-      expected = "CREATE TABLE `people` (#{type} INDEX `index_people_on_last_name`  (`last_name`)) ENGINE=InnoDB"
+      expected = "CREATE TABLE `people` (#{type} INDEX `index_people_on_last_name`  (`last_name`))"
       actual = ActiveRecord::Base.connection.create_table(:people, id: false) do |t|
         t.index :last_name, type: type
       end
       assert_equal expected, actual
     end
 
-    expected = "CREATE TABLE `people` ( INDEX `index_people_on_last_name` USING btree (`last_name`(10))) ENGINE=InnoDB"
+    expected = "CREATE TABLE `people` ( INDEX `index_people_on_last_name` USING btree (`last_name`(10)))"
     actual = ActiveRecord::Base.connection.create_table(:people, id: false) do |t|
       t.index :last_name, length: 10, using: :btree
     end
@@ -89,8 +94,8 @@ class Mysql2ActiveSchemaTest < ActiveRecord::Mysql2TestCase
       assert_equal expected, actual
     end
 
-    expected = "ALTER TABLE `peaple` ADD  INDEX `index_peaple_on_last_name` USING btree (`last_name`(10)), ALGORITHM = COPY"
-    actual = ActiveRecord::Base.connection.change_table(:peaple, bulk: true) do |t|
+    expected = "ALTER TABLE `people` ADD  INDEX `index_people_on_last_name` USING btree (`last_name`(10)), ALGORITHM = COPY"
+    actual = ActiveRecord::Base.connection.change_table(:people, bulk: true) do |t|
       t.index :last_name, length: 10, using: :btree, algorithm: :copy
     end
     assert_equal expected, actual
@@ -102,13 +107,13 @@ class Mysql2ActiveSchemaTest < ActiveRecord::Mysql2TestCase
 
   def test_create_mysql_database_with_encoding
     assert_equal "CREATE DATABASE `matt` DEFAULT CHARACTER SET `utf8`", create_database(:matt)
-    assert_equal "CREATE DATABASE `aimonetti` DEFAULT CHARACTER SET `latin1`", create_database(:aimonetti, {:charset => 'latin1'})
-    assert_equal "CREATE DATABASE `matt_aimonetti` DEFAULT CHARACTER SET `big5` COLLATE `big5_chinese_ci`", create_database(:matt_aimonetti, {:charset => :big5, :collation => :big5_chinese_ci})
+    assert_equal "CREATE DATABASE `aimonetti` DEFAULT CHARACTER SET `latin1`", create_database(:aimonetti, charset: "latin1")
+    assert_equal "CREATE DATABASE `matt_aimonetti` DEFAULT CHARACTER SET `big5` COLLATE `big5_chinese_ci`", create_database(:matt_aimonetti, charset: :big5, collation: :big5_chinese_ci)
   end
 
   def test_recreate_mysql_database_with_encoding
-    create_database(:luca, {:charset => 'latin1'})
-    assert_equal "CREATE DATABASE `luca` DEFAULT CHARACTER SET `latin1`", recreate_database(:luca, {:charset => 'latin1'})
+    create_database(:luca, charset: "latin1")
+    assert_equal "CREATE DATABASE `luca` DEFAULT CHARACTER SET `latin1`", recreate_database(:luca, charset: "latin1")
   end
 
   def test_add_column
@@ -116,11 +121,11 @@ class Mysql2ActiveSchemaTest < ActiveRecord::Mysql2TestCase
   end
 
   def test_add_column_with_limit
-    assert_equal "ALTER TABLE `people` ADD `key` varchar(32)", add_column(:people, :key, :string, :limit => 32)
+    assert_equal "ALTER TABLE `people` ADD `key` varchar(32)", add_column(:people, :key, :string, limit: 32)
   end
 
   def test_drop_table_with_specific_database
-    assert_equal "DROP TABLE `otherdb`.`people`", drop_table('otherdb.people')
+    assert_equal "DROP TABLE `otherdb`.`people`", drop_table("otherdb.people")
   end
 
   def test_add_timestamps
@@ -128,8 +133,8 @@ class Mysql2ActiveSchemaTest < ActiveRecord::Mysql2TestCase
       begin
         ActiveRecord::Base.connection.create_table :delete_me
         ActiveRecord::Base.connection.add_timestamps :delete_me, null: true
-        assert column_present?('delete_me', 'updated_at', 'datetime')
-        assert column_present?('delete_me', 'created_at', 'datetime')
+        assert column_present?("delete_me", "updated_at", "datetime")
+        assert column_present?("delete_me", "created_at", "datetime")
       ensure
         ActiveRecord::Base.connection.drop_table :delete_me rescue nil
       end
@@ -142,9 +147,9 @@ class Mysql2ActiveSchemaTest < ActiveRecord::Mysql2TestCase
         ActiveRecord::Base.connection.create_table :delete_me do |t|
           t.timestamps null: true
         end
-        ActiveRecord::Base.connection.remove_timestamps :delete_me, { null: true }
-        assert !column_present?('delete_me', 'updated_at', 'datetime')
-        assert !column_present?('delete_me', 'created_at', 'datetime')
+        ActiveRecord::Base.connection.remove_timestamps :delete_me, null: true
+        assert !column_present?("delete_me", "updated_at", "datetime")
+        assert !column_present?("delete_me", "created_at", "datetime")
       ensure
         ActiveRecord::Base.connection.drop_table :delete_me rescue nil
       end
@@ -155,7 +160,7 @@ class Mysql2ActiveSchemaTest < ActiveRecord::Mysql2TestCase
     ActiveRecord::Base.connection.stubs(:data_source_exists?).with(:temp).returns(false)
     ActiveRecord::Base.connection.stubs(:index_name_exists?).with(:index_temp_on_zip).returns(false)
 
-    expected = "CREATE TEMPORARY TABLE `temp` ( INDEX `index_temp_on_zip`  (`zip`)) ENGINE=InnoDB AS SELECT id, name, zip FROM a_really_complicated_query"
+    expected = "CREATE TEMPORARY TABLE `temp` ( INDEX `index_temp_on_zip`  (`zip`)) AS SELECT id, name, zip FROM a_really_complicated_query"
     actual = ActiveRecord::Base.connection.create_table(:temp, temporary: true, as: "SELECT id, name, zip FROM a_really_complicated_query") do |t|
       t.index :zip
     end
@@ -185,6 +190,6 @@ class Mysql2ActiveSchemaTest < ActiveRecord::Mysql2TestCase
 
     def column_present?(table_name, column_name, type)
       results = ActiveRecord::Base.connection.select_all("SHOW FIELDS FROM #{table_name} LIKE '#{column_name}'")
-      results.first && results.first['Type'] == type
+      results.first && results.first["Type"] == type
     end
 end
diff --git a/activerecord/test/cases/adapters/mysql2/auto_increment_test.rb b/activerecord/test/cases/adapters/mysql2/auto_increment_test.rb
new file mode 100644
index 0000000000..4c67633946
--- /dev/null
+++ b/activerecord/test/cases/adapters/mysql2/auto_increment_test.rb
@@ -0,0 +1,34 @@
+# frozen_string_literal: true
+
+require "cases/helper"
+require "support/schema_dumping_helper"
+
+class Mysql2AutoIncrementTest < ActiveRecord::Mysql2TestCase
+  include SchemaDumpingHelper
+
+  def setup
+    @connection = ActiveRecord::Base.connection
+  end
+
+  def teardown
+    @connection.drop_table :auto_increments, if_exists: true
+  end
+
+  def test_auto_increment_without_primary_key
+    @connection.create_table :auto_increments, id: false, force: true do |t|
+      t.integer :id, null: false, auto_increment: true
+      t.index :id
+    end
+    output = dump_table_schema("auto_increments")
+    assert_match(/t\.integer\s+"id",\s+null: false,\s+auto_increment: true$/, output)
+  end
+
+  def test_auto_increment_with_composite_primary_key
+    @connection.create_table :auto_increments, primary_key: [:id, :created_at], force: true do |t|
+      t.integer :id, null: false, auto_increment: true
+      t.datetime :created_at, null: false
+    end
+    output = dump_table_schema("auto_increments")
+    assert_match(/t\.integer\s+"id",\s+null: false,\s+auto_increment: true$/, output)
+  end
+end
diff --git a/activerecord/test/cases/adapters/mysql2/bind_parameter_test.rb b/activerecord/test/cases/adapters/mysql2/bind_parameter_test.rb
index abdf3dbf5b..825bddfb73 100644
--- a/activerecord/test/cases/adapters/mysql2/bind_parameter_test.rb
+++ b/activerecord/test/cases/adapters/mysql2/bind_parameter_test.rb
@@ -1,5 +1,7 @@
+# frozen_string_literal: true
+
 require "cases/helper"
-require 'models/topic'
+require "models/topic"
 
 module ActiveRecord
   module ConnectionAdapters
@@ -20,7 +22,7 @@ module ActiveRecord
 
         def test_create_question_marks
           str = "foo?bar"
-          x   = Topic.create!(:title => str, :content => str)
+          x   = Topic.create!(title: str, content: str)
           x.reload
           assert_equal str, x.title
           assert_equal str, x.content
@@ -39,7 +41,7 @@ module ActiveRecord
 
         def test_create_null_bytes
           str = "foo\0bar"
-          x   = Topic.create!(:title => str, :content => str)
+          x   = Topic.create!(title: str, content: str)
           x.reload
           assert_equal str, x.title
           assert_equal str, x.content
diff --git a/activerecord/test/cases/adapters/mysql2/boolean_test.rb b/activerecord/test/cases/adapters/mysql2/boolean_test.rb
index 739bb275ce..db09b30361 100644
--- a/activerecord/test/cases/adapters/mysql2/boolean_test.rb
+++ b/activerecord/test/cases/adapters/mysql2/boolean_test.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require "cases/helper"
 
 class Mysql2BooleanTest < ActiveRecord::Mysql2TestCase
@@ -38,7 +40,7 @@ class Mysql2BooleanTest < ActiveRecord::Mysql2TestCase
     assert_equal :string, string_column.type
   end
 
-  test "test type casting with emulated booleans" do
+  test "type casting with emulated booleans" do
     emulate_booleans true
 
     boolean = BooleanType.create!(archived: true, published: true)
@@ -55,7 +57,7 @@ class Mysql2BooleanTest < ActiveRecord::Mysql2TestCase
     assert_equal 0, @connection.type_cast(false)
   end
 
-  test "test type casting without emulated booleans" do
+  test "type casting without emulated booleans" do
     emulate_booleans false
 
     boolean = BooleanType.create!(archived: true, published: true)
@@ -86,11 +88,11 @@ class Mysql2BooleanTest < ActiveRecord::Mysql2TestCase
   end
 
   def boolean_column
-    BooleanType.columns.find { |c| c.name == 'archived' }
+    BooleanType.columns.find { |c| c.name == "archived" }
   end
 
   def string_column
-    BooleanType.columns.find { |c| c.name == 'published' }
+    BooleanType.columns.find { |c| c.name == "published" }
   end
 
   def emulate_booleans(value)
diff --git a/activerecord/test/cases/adapters/mysql2/case_sensitivity_test.rb b/activerecord/test/cases/adapters/mysql2/case_sensitivity_test.rb
index 9cb05119a2..fd5f712f1a 100644
--- a/activerecord/test/cases/adapters/mysql2/case_sensitivity_test.rb
+++ b/activerecord/test/cases/adapters/mysql2/case_sensitivity_test.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require "cases/helper"
 
 class Mysql2CaseSensitivityTest < ActiveRecord::Mysql2TestCase
@@ -7,46 +9,46 @@ class Mysql2CaseSensitivityTest < ActiveRecord::Mysql2TestCase
   repair_validations(CollationTest)
 
   def test_columns_include_collation_different_from_table
-    assert_equal 'utf8_bin', CollationTest.columns_hash['string_cs_column'].collation
-    assert_equal 'utf8_general_ci', CollationTest.columns_hash['string_ci_column'].collation
+    assert_equal "utf8_bin", CollationTest.columns_hash["string_cs_column"].collation
+    assert_equal "utf8_general_ci", CollationTest.columns_hash["string_ci_column"].collation
   end
 
   def test_case_sensitive
-    assert !CollationTest.columns_hash['string_ci_column'].case_sensitive?
-    assert CollationTest.columns_hash['string_cs_column'].case_sensitive?
+    assert !CollationTest.columns_hash["string_ci_column"].case_sensitive?
+    assert CollationTest.columns_hash["string_cs_column"].case_sensitive?
   end
 
   def test_case_insensitive_comparison_for_ci_column
-    CollationTest.validates_uniqueness_of(:string_ci_column, :case_sensitive => false)
-    CollationTest.create!(:string_ci_column => 'A')
-    invalid = CollationTest.new(:string_ci_column => 'a')
+    CollationTest.validates_uniqueness_of(:string_ci_column, case_sensitive: false)
+    CollationTest.create!(string_ci_column: "A")
+    invalid = CollationTest.new(string_ci_column: "a")
     queries = assert_sql { invalid.save }
     ci_uniqueness_query = queries.detect { |q| q.match(/string_ci_column/) }
     assert_no_match(/lower/i, ci_uniqueness_query)
   end
 
   def test_case_insensitive_comparison_for_cs_column
-    CollationTest.validates_uniqueness_of(:string_cs_column, :case_sensitive => false)
-    CollationTest.create!(:string_cs_column => 'A')
-    invalid = CollationTest.new(:string_cs_column => 'a')
+    CollationTest.validates_uniqueness_of(:string_cs_column, case_sensitive: false)
+    CollationTest.create!(string_cs_column: "A")
+    invalid = CollationTest.new(string_cs_column: "a")
     queries = assert_sql { invalid.save }
-    cs_uniqueness_query = queries.detect { |q| q.match(/string_cs_column/)}
+    cs_uniqueness_query = queries.detect { |q| q.match(/string_cs_column/) }
     assert_match(/lower/i, cs_uniqueness_query)
   end
 
   def test_case_sensitive_comparison_for_ci_column
-    CollationTest.validates_uniqueness_of(:string_ci_column, :case_sensitive => true)
-    CollationTest.create!(:string_ci_column => 'A')
-    invalid = CollationTest.new(:string_ci_column => 'A')
+    CollationTest.validates_uniqueness_of(:string_ci_column, case_sensitive: true)
+    CollationTest.create!(string_ci_column: "A")
+    invalid = CollationTest.new(string_ci_column: "A")
     queries = assert_sql { invalid.save }
     ci_uniqueness_query = queries.detect { |q| q.match(/string_ci_column/) }
     assert_match(/binary/i, ci_uniqueness_query)
   end
 
   def test_case_sensitive_comparison_for_cs_column
-    CollationTest.validates_uniqueness_of(:string_cs_column, :case_sensitive => true)
-    CollationTest.create!(:string_cs_column => 'A')
-    invalid = CollationTest.new(:string_cs_column => 'A')
+    CollationTest.validates_uniqueness_of(:string_cs_column, case_sensitive: true)
+    CollationTest.create!(string_cs_column: "A")
+    invalid = CollationTest.new(string_cs_column: "A")
     queries = assert_sql { invalid.save }
     cs_uniqueness_query = queries.detect { |q| q.match(/string_cs_column/) }
     assert_no_match(/binary/i, cs_uniqueness_query)
@@ -54,8 +56,8 @@ class Mysql2CaseSensitivityTest < ActiveRecord::Mysql2TestCase
 
   def test_case_sensitive_comparison_for_binary_column
     CollationTest.validates_uniqueness_of(:binary_column, case_sensitive: true)
-    CollationTest.create!(binary_column: 'A')
-    invalid = CollationTest.new(binary_column: 'A')
+    CollationTest.create!(binary_column: "A")
+    invalid = CollationTest.new(binary_column: "A")
     queries = assert_sql { invalid.save }
     bin_uniqueness_query = queries.detect { |q| q.match(/binary_column/) }
     assert_no_match(/\bBINARY\b/, bin_uniqueness_query)
diff --git a/activerecord/test/cases/adapters/mysql2/charset_collation_test.rb b/activerecord/test/cases/adapters/mysql2/charset_collation_test.rb
index c8028b6b36..d0c57de65d 100644
--- a/activerecord/test/cases/adapters/mysql2/charset_collation_test.rb
+++ b/activerecord/test/cases/adapters/mysql2/charset_collation_test.rb
@@ -1,5 +1,7 @@
+# frozen_string_literal: true
+
 require "cases/helper"
-require 'support/schema_dumping_helper'
+require "support/schema_dumping_helper"
 
 class Mysql2CharsetCollationTest < ActiveRecord::Mysql2TestCase
   include SchemaDumpingHelper
@@ -8,8 +10,8 @@ class Mysql2CharsetCollationTest < ActiveRecord::Mysql2TestCase
   setup do
     @connection = ActiveRecord::Base.connection
     @connection.create_table :charset_collations, force: true do |t|
-      t.string :string_ascii_bin, charset: 'ascii', collation: 'ascii_bin'
-      t.text :text_ucs2_unicode_ci, charset: 'ucs2', collation: 'ucs2_unicode_ci'
+      t.string :string_ascii_bin, charset: "ascii", collation: "ascii_bin"
+      t.text :text_ucs2_unicode_ci, charset: "ucs2", collation: "ucs2_unicode_ci"
     end
   end
 
@@ -18,37 +20,37 @@ class Mysql2CharsetCollationTest < ActiveRecord::Mysql2TestCase
   end
 
   test "string column with charset and collation" do
-    column = @connection.columns(:charset_collations).find { |c| c.name == 'string_ascii_bin' }
+    column = @connection.columns(:charset_collations).find { |c| c.name == "string_ascii_bin" }
     assert_equal :string, column.type
-    assert_equal 'ascii_bin', column.collation
+    assert_equal "ascii_bin", column.collation
   end
 
   test "text column with charset and collation" do
-    column = @connection.columns(:charset_collations).find { |c| c.name == 'text_ucs2_unicode_ci' }
+    column = @connection.columns(:charset_collations).find { |c| c.name == "text_ucs2_unicode_ci" }
     assert_equal :text, column.type
-    assert_equal 'ucs2_unicode_ci', column.collation
+    assert_equal "ucs2_unicode_ci", column.collation
   end
 
   test "add column with charset and collation" do
-    @connection.add_column :charset_collations, :title, :string, charset: 'utf8', collation: 'utf8_bin'
+    @connection.add_column :charset_collations, :title, :string, charset: "utf8", collation: "utf8_bin"
 
-    column = @connection.columns(:charset_collations).find { |c| c.name == 'title' }
+    column = @connection.columns(:charset_collations).find { |c| c.name == "title" }
     assert_equal :string, column.type
-    assert_equal 'utf8_bin', column.collation
+    assert_equal "utf8_bin", column.collation
   end
 
   test "change column with charset and collation" do
-    @connection.add_column :charset_collations, :description, :string, charset: 'utf8', collation: 'utf8_unicode_ci'
-    @connection.change_column :charset_collations, :description, :text, charset: 'utf8', collation: 'utf8_general_ci'
+    @connection.add_column :charset_collations, :description, :string, charset: "utf8", collation: "utf8_unicode_ci"
+    @connection.change_column :charset_collations, :description, :text, charset: "utf8", collation: "utf8_general_ci"
 
-    column = @connection.columns(:charset_collations).find { |c| c.name == 'description' }
+    column = @connection.columns(:charset_collations).find { |c| c.name == "description" }
     assert_equal :text, column.type
-    assert_equal 'utf8_general_ci', column.collation
+    assert_equal "utf8_general_ci", column.collation
   end
 
   test "schema dump includes collation" do
     output = dump_table_schema("charset_collations")
-    assert_match %r{t.string\s+"string_ascii_bin",\s+collation: "ascii_bin"$}, output
-    assert_match %r{t.text\s+"text_ucs2_unicode_ci",\s+collation: "ucs2_unicode_ci"$}, output
+    assert_match %r{t\.string\s+"string_ascii_bin",\s+collation: "ascii_bin"$}, output
+    assert_match %r{t\.text\s+"text_ucs2_unicode_ci",\s+collation: "ucs2_unicode_ci"$}, output
   end
 end
diff --git a/activerecord/test/cases/adapters/mysql2/connection_test.rb b/activerecord/test/cases/adapters/mysql2/connection_test.rb
index fe610ae951..13b4096671 100644
--- a/activerecord/test/cases/adapters/mysql2/connection_test.rb
+++ b/activerecord/test/cases/adapters/mysql2/connection_test.rb
@@ -1,5 +1,7 @@
+# frozen_string_literal: true
+
 require "cases/helper"
-require 'support/connection_helper'
+require "support/connection_helper"
 
 class Mysql2ConnectionTest < ActiveRecord::Mysql2TestCase
   include ConnectionHelper
@@ -9,7 +11,7 @@ class Mysql2ConnectionTest < ActiveRecord::Mysql2TestCase
   def setup
     super
     @subscriber = SQLSubscriber.new
-    @subscription = ActiveSupport::Notifications.subscribe('sql.active_record', @subscriber)
+    @subscription = ActiveSupport::Notifications.subscribe("sql.active_record", @subscriber)
     @connection = ActiveRecord::Base.connection
   end
 
@@ -20,9 +22,9 @@ class Mysql2ConnectionTest < ActiveRecord::Mysql2TestCase
 
   def test_bad_connection
     assert_raise ActiveRecord::NoDatabaseError do
-      configuration = ActiveRecord::Base.configurations['arunit'].merge(database: 'inexistent_activerecord_unittest')
+      configuration = ActiveRecord::Base.configurations["arunit"].merge(database: "inexistent_activerecord_unittest")
       connection = ActiveRecord::Base.mysql2_connection(configuration)
-      connection.drop_table 'ex', if_exists: true
+      connection.drop_table "ex", if_exists: true
     end
   end
 
@@ -39,17 +41,17 @@ class Mysql2ConnectionTest < ActiveRecord::Mysql2TestCase
 
   def test_no_automatic_reconnection_after_timeout
     assert @connection.active?
-    @connection.update('set @@wait_timeout=1')
+    @connection.update("set @@wait_timeout=1")
     sleep 2
     assert !@connection.active?
-
+  ensure
     # Repair all fixture connections so other tests won't break.
     @fixture_connections.each(&:verify!)
   end
 
   def test_successful_reconnection_after_timeout_with_manual_reconnect
     assert @connection.active?
-    @connection.update('set @@wait_timeout=1')
+    @connection.update("set @@wait_timeout=1")
     sleep 2
     @connection.reconnect!
     assert @connection.active?
@@ -57,15 +59,53 @@ class Mysql2ConnectionTest < ActiveRecord::Mysql2TestCase
 
   def test_successful_reconnection_after_timeout_with_verify
     assert @connection.active?
-    @connection.update('set @@wait_timeout=1')
+    @connection.update("set @@wait_timeout=1")
     sleep 2
     @connection.verify!
     assert @connection.active?
   end
 
+  def test_execute_after_disconnect
+    @connection.disconnect!
+
+    error = assert_raise(ActiveRecord::StatementInvalid) do
+      @connection.execute("SELECT 1")
+    end
+    assert_kind_of Mysql2::Error, error.cause
+  end
+
+  def test_quote_after_disconnect
+    @connection.disconnect!
+
+    assert_raise(Mysql2::Error) do
+      @connection.quote("string")
+    end
+  end
+
+  def test_active_after_disconnect
+    @connection.disconnect!
+    assert_equal false, @connection.active?
+  end
+
+  def test_wait_timeout_as_string
+    run_without_connection do |orig_connection|
+      ActiveRecord::Base.establish_connection(orig_connection.merge(wait_timeout: "60"))
+      result = ActiveRecord::Base.connection.select_value("SELECT @@SESSION.wait_timeout")
+      assert_equal 60, result
+    end
+  end
+
+  def test_wait_timeout_as_url
+    run_without_connection do |orig_connection|
+      ActiveRecord::Base.establish_connection(orig_connection.merge("url" => "mysql2:///?wait_timeout=60"))
+      result = ActiveRecord::Base.connection.select_value("SELECT @@SESSION.wait_timeout")
+      assert_equal 60, result
+    end
+  end
+
   def test_mysql_connection_collation_is_configured
-    assert_equal 'utf8_unicode_ci', @connection.show_variable('collation_connection')
-    assert_equal 'utf8_general_ci', ARUnit2Model.connection.show_variable('collation_connection')
+    assert_equal "utf8_unicode_ci", @connection.show_variable("collation_connection")
+    assert_equal "utf8_general_ci", ARUnit2Model.connection.show_variable("collation_connection")
   end
 
   def test_mysql_default_in_strict_mode
@@ -92,29 +132,29 @@ class Mysql2ConnectionTest < ActiveRecord::Mysql2TestCase
 
   def test_mysql_sql_mode_variable_overrides_strict_mode
     run_without_connection do |orig_connection|
-      ActiveRecord::Base.establish_connection(orig_connection.deep_merge(variables: { 'sql_mode' => 'ansi' }))
-      result = ActiveRecord::Base.connection.select_value('SELECT @@SESSION.sql_mode')
+      ActiveRecord::Base.establish_connection(orig_connection.deep_merge(variables: { "sql_mode" => "ansi" }))
+      result = ActiveRecord::Base.connection.select_value("SELECT @@SESSION.sql_mode")
       assert_no_match %r(STRICT_ALL_TABLES), result
     end
   end
 
-  def test_passing_arbitary_flags_to_adapter
+  def test_passing_arbitrary_flags_to_adapter
     run_without_connection do |orig_connection|
-      ActiveRecord::Base.establish_connection(orig_connection.merge({flags: Mysql2::Client::COMPRESS}))
-      assert_equal (Mysql2::Client::COMPRESS |  Mysql2::Client::FOUND_ROWS), ActiveRecord::Base.connection.raw_connection.query_options[:flags]
+      ActiveRecord::Base.establish_connection(orig_connection.merge(flags: Mysql2::Client::COMPRESS))
+      assert_equal (Mysql2::Client::COMPRESS | Mysql2::Client::FOUND_ROWS), ActiveRecord::Base.connection.raw_connection.query_options[:flags]
     end
   end
 
   def test_passing_flags_by_array_to_adapter
     run_without_connection do |orig_connection|
-      ActiveRecord::Base.establish_connection(orig_connection.merge({flags: ['COMPRESS'] }))
+      ActiveRecord::Base.establish_connection(orig_connection.merge(flags: ["COMPRESS"]))
       assert_equal ["COMPRESS", "FOUND_ROWS"], ActiveRecord::Base.connection.raw_connection.query_options[:flags]
     end
   end
 
   def test_mysql_set_session_variable
     run_without_connection do |orig_connection|
-      ActiveRecord::Base.establish_connection(orig_connection.deep_merge({:variables => {:default_week_format => 3}}))
+      ActiveRecord::Base.establish_connection(orig_connection.deep_merge(variables: { default_week_format: 3 }))
       session_mode = ActiveRecord::Base.connection.exec_query "SELECT @@SESSION.DEFAULT_WEEK_FORMAT"
       assert_equal 3, session_mode.rows.first.first.to_i
     end
@@ -122,7 +162,7 @@ class Mysql2ConnectionTest < ActiveRecord::Mysql2TestCase
 
   def test_mysql_set_session_variable_to_default
     run_without_connection do |orig_connection|
-      ActiveRecord::Base.establish_connection(orig_connection.deep_merge({:variables => {:default_week_format => :default}}))
+      ActiveRecord::Base.establish_connection(orig_connection.deep_merge(variables: { default_week_format: :default }))
       global_mode = ActiveRecord::Base.connection.exec_query "SELECT @@GLOBAL.DEFAULT_WEEK_FORMAT"
       session_mode = ActiveRecord::Base.connection.exec_query "SELECT @@SESSION.DEFAULT_WEEK_FORMAT"
       assert_equal global_mode.rows, session_mode.rows
@@ -130,14 +170,14 @@ class Mysql2ConnectionTest < ActiveRecord::Mysql2TestCase
   end
 
   def test_logs_name_show_variable
-    @connection.show_variable 'foo'
+    @connection.show_variable "foo"
     assert_equal "SCHEMA", @subscriber.logged[0][1]
   end
 
-  def test_logs_name_rename_column_sql
+  def test_logs_name_rename_column_for_alter
     @connection.execute "CREATE TABLE `bar_baz` (`foo` varchar(255))"
     @subscriber.logged.clear
-    @connection.send(:rename_column_sql, 'bar_baz', 'foo', 'foo2')
+    @connection.send(:rename_column_for_alter, "bar_baz", "foo", "foo2")
     assert_equal "SCHEMA", @subscriber.logged[0][1]
   ensure
     @connection.execute "DROP TABLE `bar_baz`"
@@ -155,19 +195,19 @@ class Mysql2ConnectionTest < ActiveRecord::Mysql2TestCase
     released_lock = @connection.release_advisory_lock(lock_name)
     assert released_lock, "expected release_advisory_lock to return true but it didn't"
 
-    assert test_lock_free(lock_name), 'expected the test lock to be available after releasing'
+    assert test_lock_free(lock_name), "expected the test lock to be available after releasing"
   end
 
   def test_release_non_existent_advisory_lock
     lock_name = "fake lock'n'name"
     released_non_existent_lock = @connection.release_advisory_lock(lock_name)
     assert_equal released_non_existent_lock, false,
-      'expected release_advisory_lock to return false when there was no lock to release'
+      "expected release_advisory_lock to return false when there was no lock to release"
   end
 
-  protected
+  private
 
-  def test_lock_free(lock_name)
-    @connection.select_value("SELECT IS_FREE_LOCK(#{@connection.quote(lock_name)})") == 1
-  end
+    def test_lock_free(lock_name)
+      @connection.select_value("SELECT IS_FREE_LOCK(#{@connection.quote(lock_name)})") == 1
+    end
 end
diff --git a/activerecord/test/cases/adapters/mysql2/datetime_precision_quoting_test.rb b/activerecord/test/cases/adapters/mysql2/datetime_precision_quoting_test.rb
index e349c67c93..fa54f39992 100644
--- a/activerecord/test/cases/adapters/mysql2/datetime_precision_quoting_test.rb
+++ b/activerecord/test/cases/adapters/mysql2/datetime_precision_quoting_test.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require "cases/helper"
 
 class Mysql2DatetimePrecisionQuotingTest < ActiveRecord::Mysql2TestCase
@@ -5,24 +7,28 @@ class Mysql2DatetimePrecisionQuotingTest < ActiveRecord::Mysql2TestCase
     @connection = ActiveRecord::Base.connection
   end
 
-  test 'microsecond precision for MySQL gte 5.6.4' do
-    stub_version '5.6.4'
-    assert_microsecond_precision
+  test "microsecond precision for MySQL gte 5.6.4" do
+    stub_version "5.6.4" do
+      assert_microsecond_precision
+    end
   end
 
-  test 'no microsecond precision for MySQL lt 5.6.4' do
-    stub_version '5.6.3'
-    assert_no_microsecond_precision
+  test "no microsecond precision for MySQL lt 5.6.4" do
+    stub_version "5.6.3" do
+      assert_no_microsecond_precision
+    end
   end
 
-  test 'microsecond precision for MariaDB gte 5.3.0' do
-    stub_version '5.5.5-10.1.8-MariaDB-log'
-    assert_microsecond_precision
+  test "microsecond precision for MariaDB gte 5.3.0" do
+    stub_version "5.5.5-10.1.8-MariaDB-log" do
+      assert_microsecond_precision
+    end
   end
 
-  test 'no microsecond precision for MariaDB lt 5.3.0' do
-    stub_version '5.2.9-MariaDB'
-    assert_no_microsecond_precision
+  test "no microsecond precision for MariaDB lt 5.3.0" do
+    stub_version "5.2.9-MariaDB" do
+      assert_no_microsecond_precision
+    end
   end
 
   private
@@ -41,5 +47,8 @@ class Mysql2DatetimePrecisionQuotingTest < ActiveRecord::Mysql2TestCase
     def stub_version(full_version_string)
       @connection.stubs(:full_version).returns(full_version_string)
       @connection.remove_instance_variable(:@version) if @connection.instance_variable_defined?(:@version)
+      yield
+    ensure
+      @connection.remove_instance_variable(:@version) if @connection.instance_variable_defined?(:@version)
     end
 end
diff --git a/activerecord/test/cases/adapters/mysql2/enum_test.rb b/activerecord/test/cases/adapters/mysql2/enum_test.rb
index 35dbc76d1b..108bec832c 100644
--- a/activerecord/test/cases/adapters/mysql2/enum_test.rb
+++ b/activerecord/test/cases/adapters/mysql2/enum_test.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require "cases/helper"
 
 class Mysql2EnumTest < ActiveRecord::Mysql2TestCase
@@ -5,22 +7,17 @@ class Mysql2EnumTest < ActiveRecord::Mysql2TestCase
   end
 
   def test_enum_limit
-    column = EnumTest.columns_hash['enum_column']
+    column = EnumTest.columns_hash["enum_column"]
     assert_equal 8, column.limit
   end
 
-  def test_should_not_be_blob_or_text_column
-    column = EnumTest.columns_hash['enum_column']
-    assert_not column.blob_or_text_column?
-  end
-
   def test_should_not_be_unsigned
-    column = EnumTest.columns_hash['enum_column']
+    column = EnumTest.columns_hash["enum_column"]
     assert_not column.unsigned?
   end
 
   def test_should_not_be_bigint
-    column = EnumTest.columns_hash['enum_column']
+    column = EnumTest.columns_hash["enum_column"]
     assert_not column.bigint?
   end
 end
diff --git a/activerecord/test/cases/adapters/mysql2/explain_test.rb b/activerecord/test/cases/adapters/mysql2/explain_test.rb
index b783b5fcd9..b8e778f0b0 100644
--- a/activerecord/test/cases/adapters/mysql2/explain_test.rb
+++ b/activerecord/test/cases/adapters/mysql2/explain_test.rb
@@ -1,21 +1,23 @@
+# frozen_string_literal: true
+
 require "cases/helper"
-require 'models/developer'
-require 'models/computer'
+require "models/author"
+require "models/post"
 
 class Mysql2ExplainTest < ActiveRecord::Mysql2TestCase
-  fixtures :developers
+  fixtures :authors
 
   def test_explain_for_one_query
-    explain = Developer.where(id: 1).explain
-    assert_match %(EXPLAIN for: SELECT `developers`.* FROM `developers` WHERE `developers`.`id` = 1), explain
-    assert_match %r(developers |.* const), explain
+    explain = Author.where(id: 1).explain
+    assert_match %(EXPLAIN for: SELECT `authors`.* FROM `authors` WHERE `authors`.`id` = 1), explain
+    assert_match %r(authors |.* const), explain
   end
 
   def test_explain_with_eager_loading
-    explain = Developer.where(id: 1).includes(:audit_logs).explain
-    assert_match %(EXPLAIN for: SELECT `developers`.* FROM `developers` WHERE `developers`.`id` = 1), explain
-    assert_match %r(developers |.* const), explain
-    assert_match %(EXPLAIN for: SELECT `audit_logs`.* FROM `audit_logs` WHERE `audit_logs`.`developer_id` = 1), explain
-    assert_match %r(audit_logs |.* ALL), explain
+    explain = Author.where(id: 1).includes(:posts).explain
+    assert_match %(EXPLAIN for: SELECT `authors`.* FROM `authors` WHERE `authors`.`id` = 1), explain
+    assert_match %r(authors |.* const), explain
+    assert_match %(EXPLAIN for: SELECT `posts`.* FROM `posts` WHERE `posts`.`author_id` = 1), explain
+    assert_match %r(posts |.* ALL), explain
   end
 end
diff --git a/activerecord/test/cases/adapters/mysql2/json_test.rb b/activerecord/test/cases/adapters/mysql2/json_test.rb
index 9c3fef1b59..de78ba91f5 100644
--- a/activerecord/test/cases/adapters/mysql2/json_test.rb
+++ b/activerecord/test/cases/adapters/mysql2/json_test.rb
@@ -1,179 +1,24 @@
-require 'cases/helper'
-require 'support/schema_dumping_helper'
+# frozen_string_literal: true
 
-if ActiveRecord::Base.connection.supports_json?
-class Mysql2JSONTest < ActiveRecord::Mysql2TestCase
-  include SchemaDumpingHelper
-  self.use_transactional_tests = false
-
-  class JsonDataType < ActiveRecord::Base
-    self.table_name = 'json_data_type'
-
-    store_accessor :settings, :resolution
-  end
+require "cases/helper"
+require "cases/json_shared_test_cases"
 
-  def setup
-    @connection = ActiveRecord::Base.connection
-    begin
-      @connection.create_table('json_data_type') do |t|
-        t.json 'payload'
-        t.json 'settings'
+if ActiveRecord::Base.connection.supports_json?
+  class Mysql2JSONTest < ActiveRecord::Mysql2TestCase
+    include JSONSharedTestCases
+    self.use_transactional_tests = false
+
+    def setup
+      super
+      @connection.create_table("json_data_type") do |t|
+        t.json "payload"
+        t.json "settings"
       end
     end
-  end
-
-  def teardown
-    @connection.drop_table :json_data_type, if_exists: true
-    JsonDataType.reset_column_information
-  end
-
-  def test_column
-    column = JsonDataType.columns_hash["payload"]
-    assert_equal :json, column.type
-    assert_equal 'json', column.sql_type
-
-    type = JsonDataType.type_for_attribute("payload")
-    assert_not type.binary?
-  end
-
-  def test_change_table_supports_json
-    @connection.change_table('json_data_type') do |t|
-      t.json 'users'
-    end
-    JsonDataType.reset_column_information
-    column = JsonDataType.columns_hash['users']
-    assert_equal :json, column.type
-  end
-
-  def test_schema_dumping
-    output = dump_table_schema("json_data_type")
-    assert_match(/t\.json\s+"settings"/, output)
-  end
-
-  def test_cast_value_on_write
-    x = JsonDataType.new payload: {"string" => "foo", :symbol => :bar}
-    assert_equal({"string" => "foo", :symbol => :bar}, x.payload_before_type_cast)
-    assert_equal({"string" => "foo", "symbol" => "bar"}, x.payload)
-    x.save
-    assert_equal({"string" => "foo", "symbol" => "bar"}, x.reload.payload)
-  end
-
-  def test_type_cast_json
-    type = JsonDataType.type_for_attribute("payload")
-
-    data = "{\"a_key\":\"a_value\"}"
-    hash = type.deserialize(data)
-    assert_equal({'a_key' => 'a_value'}, hash)
-    assert_equal({'a_key' => 'a_value'}, type.deserialize(data))
-
-    assert_equal({}, type.deserialize("{}"))
-    assert_equal({'key'=>nil}, type.deserialize('{"key": null}'))
-    assert_equal({'c'=>'}','"a"'=>'b "a b'}, type.deserialize(%q({"c":"}", "\"a\"":"b \"a b"})))
-  end
-
-  def test_rewrite
-    @connection.execute "insert into json_data_type (payload) VALUES ('{\"k\":\"v\"}')"
-    x = JsonDataType.first
-    x.payload = { '"a\'' => 'b' }
-    assert x.save!
-  end
-
-  def test_select
-    @connection.execute "insert into json_data_type (payload) VALUES ('{\"k\":\"v\"}')"
-    x = JsonDataType.first
-    assert_equal({'k' => 'v'}, x.payload)
-  end
-
-  def test_select_multikey
-    @connection.execute %q|insert into json_data_type (payload) VALUES ('{"k1":"v1", "k2":"v2", "k3":[1,2,3]}')|
-    x = JsonDataType.first
-    assert_equal({'k1' => 'v1', 'k2' => 'v2', 'k3' => [1,2,3]}, x.payload)
-  end
-
-  def test_null_json
-    @connection.execute %q|insert into json_data_type (payload) VALUES(null)|
-    x = JsonDataType.first
-    assert_equal(nil, x.payload)
-  end
-
-  def test_select_array_json_value
-    @connection.execute %q|insert into json_data_type (payload) VALUES ('["v0",{"k1":"v1"}]')|
-    x = JsonDataType.first
-    assert_equal(['v0', {'k1' => 'v1'}], x.payload)
-  end
-
-  def test_rewrite_array_json_value
-    @connection.execute %q|insert into json_data_type (payload) VALUES ('["v0",{"k1":"v1"}]')|
-    x = JsonDataType.first
-    x.payload = ['v1', {'k2' => 'v2'}, 'v3']
-    assert x.save!
-  end
-
-  def test_with_store_accessors
-    x = JsonDataType.new(resolution: "320×480")
-    assert_equal "320×480", x.resolution
-
-    x.save!
-    x = JsonDataType.first
-    assert_equal "320×480", x.resolution
-
-    x.resolution = "640×1136"
-    x.save!
 
-    x = JsonDataType.first
-    assert_equal "640×1136", x.resolution
-  end
-
-  def test_duplication_with_store_accessors
-    x = JsonDataType.new(resolution: "320×480")
-    assert_equal "320×480", x.resolution
-
-    y = x.dup
-    assert_equal "320×480", y.resolution
-  end
-
-  def test_yaml_round_trip_with_store_accessors
-    x = JsonDataType.new(resolution: "320×480")
-    assert_equal "320×480", x.resolution
-
-    y = YAML.load(YAML.dump(x))
-    assert_equal "320×480", y.resolution
-  end
-
-  def test_changes_in_place
-    json = JsonDataType.new
-    assert_not json.changed?
-
-    json.payload = { 'one' => 'two' }
-    assert json.changed?
-    assert json.payload_changed?
-
-    json.save!
-    assert_not json.changed?
-
-    json.payload['three'] = 'four'
-    assert json.payload_changed?
-
-    json.save!
-    json.reload
-
-    assert_equal({ 'one' => 'two', 'three' => 'four' }, json.payload)
-    assert_not json.changed?
-  end
-
-  def test_assigning_string_literal
-    json = JsonDataType.create(payload: "foo")
-    assert_equal "foo", json.payload
-  end
-
-  def test_assigning_number
-    json = JsonDataType.create(payload: 1.234)
-    assert_equal 1.234, json.payload
-  end
-
-  def test_assigning_boolean
-    json = JsonDataType.create(payload: true)
-    assert_equal true, json.payload
+    private
+      def column_type
+        :json
+      end
   end
 end
-end
diff --git a/activerecord/test/cases/adapters/mysql2/mysql2_adapter_test.rb b/activerecord/test/cases/adapters/mysql2/mysql2_adapter_test.rb
index 61dd0828d0..d18fb97e05 100644
--- a/activerecord/test/cases/adapters/mysql2/mysql2_adapter_test.rb
+++ b/activerecord/test/cases/adapters/mysql2/mysql2_adapter_test.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require "cases/helper"
 require "support/ddl_helper"
 
@@ -11,23 +13,12 @@ class Mysql2AdapterTest < ActiveRecord::Mysql2TestCase
   def test_exec_query_nothing_raises_with_no_result_queries
     assert_nothing_raised do
       with_example_table do
-        @conn.exec_query('INSERT INTO ex (number) VALUES (1)')
-        @conn.exec_query('DELETE FROM ex WHERE number = 1')
+        @conn.exec_query("INSERT INTO ex (number) VALUES (1)")
+        @conn.exec_query("DELETE FROM ex WHERE number = 1")
       end
     end
   end
 
-  def test_valid_column
-    with_example_table do
-      column = @conn.columns('ex').find { |col| col.name == 'id' }
-      assert @conn.valid_type?(column.type)
-    end
-  end
-
-  def test_invalid_column
-    assert_not @conn.valid_type?(:foobar)
-  end
-
   def test_columns_for_distinct_zero_orders
     assert_equal "posts.id",
       @conn.columns_for_distinct("posts.id", [])
@@ -45,8 +36,8 @@ class Mysql2AdapterTest < ActiveRecord::Mysql2TestCase
 
   def test_columns_for_distinct_with_case
     assert_equal(
-      'posts.id, CASE WHEN author.is_active THEN UPPER(author.name) ELSE UPPER(author.email) END AS alias_0',
-      @conn.columns_for_distinct('posts.id',
+      "posts.id, CASE WHEN author.is_active THEN UPPER(author.name) ELSE UPPER(author.email) END AS alias_0",
+      @conn.columns_for_distinct("posts.id",
         ["CASE WHEN author.is_active THEN UPPER(author.name) ELSE UPPER(author.email) END"])
     )
   end
@@ -65,9 +56,22 @@ class Mysql2AdapterTest < ActiveRecord::Mysql2TestCase
       @conn.columns_for_distinct("posts.id", [order])
   end
 
-  private
+  def test_errors_for_bigint_fks_on_integer_pk_table
+    # table old_cars has primary key of integer
 
-  def with_example_table(definition = 'id int auto_increment primary key, number int, data varchar(255)', &block)
-    super(@conn, 'ex', definition, &block)
+    error = assert_raises(ActiveRecord::MismatchedForeignKey) do
+      @conn.add_reference :engines, :old_car
+      @conn.add_foreign_key :engines, :old_cars
+    end
+
+    assert_match "Column `old_car_id` on table `engines` has a type of `bigint(20)`", error.message
+    assert_not_nil error.cause
+    @conn.exec_query("ALTER TABLE engines DROP COLUMN old_car_id")
   end
+
+  private
+
+    def with_example_table(definition = "id int auto_increment primary key, number int, data varchar(255)", &block)
+      super(@conn, "ex", definition, &block)
+    end
 end
diff --git a/activerecord/test/cases/adapters/mysql2/reserved_word_test.rb b/activerecord/test/cases/adapters/mysql2/reserved_word_test.rb
deleted file mode 100644
index ffb4e2c5cf..0000000000
--- a/activerecord/test/cases/adapters/mysql2/reserved_word_test.rb
+++ /dev/null
@@ -1,152 +0,0 @@
-require "cases/helper"
-
-# a suite of tests to ensure the ConnectionAdapters#MysqlAdapter can handle tables with
-# reserved word names (ie: group, order, values, etc...)
-class Mysql2ReservedWordTest < ActiveRecord::Mysql2TestCase
-  class Group < ActiveRecord::Base
-    Group.table_name = 'group'
-    belongs_to :select
-    has_one :values
-  end
-
-  class Select < ActiveRecord::Base
-    Select.table_name = 'select'
-    has_many :groups
-  end
-
-  class Values < ActiveRecord::Base
-    Values.table_name = 'values'
-  end
-
-  class Distinct < ActiveRecord::Base
-    Distinct.table_name = 'distinct'
-    has_and_belongs_to_many :selects
-    has_many :values, :through => :groups
-  end
-
-  def setup
-    @connection = ActiveRecord::Base.connection
-
-    # we call execute directly here (and do similar below) because ActiveRecord::Base#create_table()
-    # will fail with these table names if these test cases fail
-
-    create_tables_directly 'group'=>'id int auto_increment primary key, `order` varchar(255), select_id int',
-      'select'=>'id int auto_increment primary key',
-      'values'=>'id int auto_increment primary key, group_id int',
-      'distinct'=>'id int auto_increment primary key',
-      'distinct_select'=>'distinct_id int, select_id int'
-  end
-
-  teardown do
-    drop_tables_directly ['group', 'select', 'values', 'distinct', 'distinct_select', 'order']
-  end
-
-  # create tables with reserved-word names and columns
-  def test_create_tables
-    assert_nothing_raised {
-      @connection.create_table :order do |t|
-        t.column :group, :string
-      end
-    }
-  end
-
-  # rename tables with reserved-word names
-  def test_rename_tables
-    assert_nothing_raised { @connection.rename_table(:group, :order) }
-  end
-
-  # alter column with a reserved-word name in a table with a reserved-word name
-  def test_change_columns
-    assert_nothing_raised { @connection.change_column_default(:group, :order, 'whatever') }
-    #the quoting here will reveal any double quoting issues in change_column's interaction with the column method in the adapter
-    assert_nothing_raised { @connection.change_column('group', 'order', :Int, :default => 0) }
-    assert_nothing_raised { @connection.rename_column(:group, :order, :values) }
-  end
-
-  # introspect table with reserved word name
-  def test_introspect
-    assert_nothing_raised { @connection.columns(:group) }
-    assert_nothing_raised { @connection.indexes(:group) }
-  end
-
-  #fixtures
-  self.use_instantiated_fixtures = true
-  self.use_transactional_tests = false
-
-  #activerecord model class with reserved-word table name
-  def test_activerecord_model
-    create_test_fixtures :select, :distinct, :group, :values, :distinct_select
-    x = nil
-    assert_nothing_raised { x = Group.new }
-    x.order = 'x'
-    assert_nothing_raised { x.save }
-    x.order = 'y'
-    assert_nothing_raised { x.save }
-    assert_nothing_raised { Group.find_by_order('y') }
-    assert_nothing_raised { Group.find(1) }
-  end
-
-  # has_one association with reserved-word table name
-  def test_has_one_associations
-    create_test_fixtures :select, :distinct, :group, :values, :distinct_select
-    v = nil
-    assert_nothing_raised { v = Group.find(1).values }
-    assert_equal 2, v.id
-  end
-
-  # belongs_to association with reserved-word table name
-  def test_belongs_to_associations
-    create_test_fixtures :select, :distinct, :group, :values, :distinct_select
-    gs = nil
-    assert_nothing_raised { gs = Select.find(2).groups }
-    assert_equal gs.length, 2
-    assert(gs.collect(&:id).sort == [2, 3])
-  end
-
-  # has_and_belongs_to_many with reserved-word table name
-  def test_has_and_belongs_to_many
-    create_test_fixtures :select, :distinct, :group, :values, :distinct_select
-    s = nil
-    assert_nothing_raised { s = Distinct.find(1).selects }
-    assert_equal s.length, 2
-    assert(s.collect(&:id).sort == [1, 2])
-  end
-
-  # activerecord model introspection with reserved-word table and column names
-  def test_activerecord_introspection
-    assert_nothing_raised { Group.table_exists? }
-    assert_nothing_raised { Group.columns }
-  end
-
-  # Calculations
-  def test_calculations_work_with_reserved_words
-    assert_nothing_raised { Group.count }
-  end
-
-  def test_associations_work_with_reserved_words
-    assert_nothing_raised { Select.all.merge!(:includes => [:groups]).to_a }
-  end
-
-  #the following functions were added to DRY test cases
-
-  private
-  # custom fixture loader, uses FixtureSet#create_fixtures and appends base_path to the current file's path
-  def create_test_fixtures(*fixture_names)
-    ActiveRecord::FixtureSet.create_fixtures(FIXTURES_ROOT + "/reserved_words", fixture_names)
-  end
-
-  # custom drop table, uses execute on connection to drop a table if it exists. note: escapes table_name
-  def drop_tables_directly(table_names, connection = @connection)
-    table_names.each do |name|
-      connection.drop_table name, if_exists: true
-    end
-  end
-
-  # custom create table, uses execute on connection to create a table, note: escapes table_name, does NOT escape columns
-  def create_tables_directly (tables, connection = @connection)
-    tables.each do |table_name, column_properties|
-      connection.execute("CREATE TABLE `#{table_name}` ( #{column_properties} )")
-    end
-  end
-
-end
diff --git a/activerecord/test/cases/adapters/mysql2/schema_migrations_test.rb b/activerecord/test/cases/adapters/mysql2/schema_migrations_test.rb
index 7c89fda582..62abd694bb 100644
--- a/activerecord/test/cases/adapters/mysql2/schema_migrations_test.rb
+++ b/activerecord/test/cases/adapters/mysql2/schema_migrations_test.rb
@@ -1,6 +1,10 @@
+# frozen_string_literal: true
+
 require "cases/helper"
 
 class SchemaMigrationsTest < ActiveRecord::Mysql2TestCase
+  self.use_transactional_tests = false
+
   def test_renaming_index_on_foreign_key
     connection.add_index "engines", "car_id"
     connection.add_foreign_key :engines, :cars, name: "fk_engines_cars"
@@ -16,9 +20,9 @@ class SchemaMigrationsTest < ActiveRecord::Mysql2TestCase
       table_name = ActiveRecord::SchemaMigration.table_name
       connection.drop_table table_name, if_exists: true
 
-      connection.initialize_schema_migrations_table
+      ActiveRecord::SchemaMigration.create_table
 
-      assert connection.column_exists?(table_name, :version, :string, collation: 'utf8_general_ci')
+      assert connection.column_exists?(table_name, :version, :string)
     end
   end
 
@@ -27,33 +31,35 @@ class SchemaMigrationsTest < ActiveRecord::Mysql2TestCase
       table_name = ActiveRecord::InternalMetadata.table_name
       connection.drop_table table_name, if_exists: true
 
-      connection.initialize_internal_metadata_table
+      ActiveRecord::InternalMetadata.create_table
 
-      assert connection.column_exists?(table_name, :key, :string, collation: 'utf8_general_ci')
+      assert connection.column_exists?(table_name, :key, :string)
     end
+  ensure
+    ActiveRecord::InternalMetadata[:environment] = ActiveRecord::Migrator.current_environment
   end
 
   private
 
-  def with_encoding_utf8mb4
-    database_name = connection.current_database
-    database_info = connection.select_one("SELECT * FROM information_schema.schemata WHERE schema_name = '#{database_name}'")
+    def with_encoding_utf8mb4
+      database_name = connection.current_database
+      database_info = connection.select_one("SELECT * FROM information_schema.schemata WHERE schema_name = '#{database_name}'")
 
-    original_charset = database_info["DEFAULT_CHARACTER_SET_NAME"]
-    original_collation = database_info["DEFAULT_COLLATION_NAME"]
+      original_charset = database_info["DEFAULT_CHARACTER_SET_NAME"]
+      original_collation = database_info["DEFAULT_COLLATION_NAME"]
 
-    execute("ALTER DATABASE #{database_name} DEFAULT CHARACTER SET utf8mb4")
+      execute("ALTER DATABASE #{database_name} DEFAULT CHARACTER SET utf8mb4")
 
-    yield
-  ensure
-    execute("ALTER DATABASE #{database_name} DEFAULT CHARACTER SET #{original_charset} COLLATE #{original_collation}")
-  end
+      yield
+    ensure
+      execute("ALTER DATABASE #{database_name} DEFAULT CHARACTER SET #{original_charset} COLLATE #{original_collation}")
+    end
 
-  def connection
-    @connection ||= ActiveRecord::Base.connection
-  end
+    def connection
+      @connection ||= ActiveRecord::Base.connection
+    end
 
-  def execute(sql)
-    connection.execute(sql)
-  end
+    def execute(sql)
+      connection.execute(sql)
+    end
 end
diff --git a/activerecord/test/cases/adapters/mysql2/schema_test.rb b/activerecord/test/cases/adapters/mysql2/schema_test.rb
index 43957791b1..b587e756cf 100644
--- a/activerecord/test/cases/adapters/mysql2/schema_test.rb
+++ b/activerecord/test/cases/adapters/mysql2/schema_test.rb
@@ -1,6 +1,8 @@
+# frozen_string_literal: true
+
 require "cases/helper"
-require 'models/post'
-require 'models/comment'
+require "models/post"
+require "models/comment"
 
 module ActiveRecord
   module ConnectionAdapters
@@ -16,7 +18,7 @@ module ActiveRecord
         @omgpost = Class.new(ActiveRecord::Base) do
           self.inheritance_column = :disabled
           self.table_name = "#{db}.#{table}"
-          def self.name; 'Post'; end
+          def self.name; "Post"; end
         end
       end
 
@@ -31,13 +33,13 @@ module ActiveRecord
           t.float :float_25, limit: 25
         end
 
-        column_no_limit = @connection.columns(:mysql_doubles).find { |c| c.name == 'float_no_limit' }
-        column_short = @connection.columns(:mysql_doubles).find { |c| c.name == 'float_short' }
-        column_long = @connection.columns(:mysql_doubles).find { |c| c.name == 'float_long' }
+        column_no_limit = @connection.columns(:mysql_doubles).find { |c| c.name == "float_no_limit" }
+        column_short = @connection.columns(:mysql_doubles).find { |c| c.name == "float_short" }
+        column_long = @connection.columns(:mysql_doubles).find { |c| c.name == "float_long" }
 
-        column_23 = @connection.columns(:mysql_doubles).find { |c| c.name == 'float_23' }
-        column_24 = @connection.columns(:mysql_doubles).find { |c| c.name == 'float_24' }
-        column_25 = @connection.columns(:mysql_doubles).find { |c| c.name == 'float_25' }
+        column_23 = @connection.columns(:mysql_doubles).find { |c| c.name == "float_23" }
+        column_24 = @connection.columns(:mysql_doubles).find { |c| c.name == "float_24" }
+        column_25 = @connection.columns(:mysql_doubles).find { |c| c.name == "float_25" }
 
         # Mysql floats are precision 0..24, Mysql doubles are precision 25..53
         assert_equal 24, column_no_limit.limit
@@ -56,7 +58,7 @@ module ActiveRecord
       end
 
       def test_primary_key
-        assert_equal 'id', @omgpost.primary_key
+        assert_equal "id", @omgpost.primary_key
       end
 
       def test_data_source_exists?
@@ -69,18 +71,18 @@ module ActiveRecord
       end
 
       def test_dump_indexes
-        index_a_name = 'index_key_tests_on_snack'
-        index_b_name = 'index_key_tests_on_pizza'
-        index_c_name = 'index_key_tests_on_awesome'
+        index_a_name = "index_key_tests_on_snack"
+        index_b_name = "index_key_tests_on_pizza"
+        index_c_name = "index_key_tests_on_awesome"
 
-        table = 'key_tests'
+        table = "key_tests"
 
         indexes = @connection.indexes(table).sort_by(&:name)
-        assert_equal 3,indexes.size
+        assert_equal 3, indexes.size
 
-        index_a = indexes.select{|i| i.name == index_a_name}[0]
-        index_b = indexes.select{|i| i.name == index_b_name}[0]
-        index_c = indexes.select{|i| i.name == index_c_name}[0]
+        index_a = indexes.select { |i| i.name == index_a_name }[0]
+        index_b = indexes.select { |i| i.name == index_b_name }[0]
+        index_c = indexes.select { |i| i.name == index_c_name }[0]
         assert_equal :btree, index_a.using
         assert_nil index_a.type
         assert_equal :btree, index_b.using
@@ -103,3 +105,24 @@ module ActiveRecord
     end
   end
 end
+
+class Mysql2AnsiQuotesTest < ActiveRecord::Mysql2TestCase
+  def setup
+    @connection = ActiveRecord::Base.connection
+    @connection.execute("SET SESSION sql_mode='ANSI_QUOTES'")
+  end
+
+  def teardown
+    @connection.reconnect!
+  end
+
+  def test_primary_key_method_with_ansi_quotes
+    assert_equal "id", @connection.primary_key("topics")
+  end
+
+  def test_foreign_keys_method_with_ansi_quotes
+    fks = @connection.foreign_keys("lessons_students")
+    assert_equal([["lessons_students", "students", :cascade]],
+                 fks.map { |fk| [fk.from_table, fk.to_table, fk.on_delete] })
+  end
+end
diff --git a/activerecord/test/cases/adapters/mysql2/sp_test.rb b/activerecord/test/cases/adapters/mysql2/sp_test.rb
index 4197ba45f1..7b6dce71e9 100644
--- a/activerecord/test/cases/adapters/mysql2/sp_test.rb
+++ b/activerecord/test/cases/adapters/mysql2/sp_test.rb
@@ -1,13 +1,15 @@
+# frozen_string_literal: true
+
 require "cases/helper"
-require 'models/topic'
-require 'models/reply'
+require "models/topic"
+require "models/reply"
 
 class Mysql2StoredProcedureTest < ActiveRecord::Mysql2TestCase
   fixtures :topics
 
   def setup
     @connection = ActiveRecord::Base.connection
-    unless ActiveRecord::Base.connection.version >= '5.6.0'
+    unless ActiveRecord::Base.connection.version >= "5.6.0"
       skip("no stored procedure support")
     end
   end
@@ -15,21 +17,21 @@ class Mysql2StoredProcedureTest < ActiveRecord::Mysql2TestCase
   # Test that MySQL allows multiple results for stored procedures
   #
   # In MySQL 5.6, CLIENT_MULTI_RESULTS is enabled by default.
-  # http://dev.mysql.com/doc/refman/5.6/en/call.html
+  # https://dev.mysql.com/doc/refman/5.6/en/call.html
   def test_multi_results
-    rows = @connection.select_rows('CALL ten();')
+    rows = @connection.select_rows("CALL ten();")
     assert_equal 10, rows[0][0].to_i, "ten() did not return 10 as expected: #{rows.inspect}"
     assert @connection.active?, "Bad connection use by 'Mysql2Adapter.select_rows'"
   end
 
   def test_multi_results_from_select_one
-    row = @connection.select_one('CALL topics(1);')
-    assert_equal 'David', row['author_name']
+    row = @connection.select_one("CALL topics(1);")
+    assert_equal "David", row["author_name"]
     assert @connection.active?, "Bad connection use by 'Mysql2Adapter.select_one'"
   end
 
   def test_multi_results_from_find_by_sql
-    topics = Topic.find_by_sql 'CALL topics(3);'
+    topics = Topic.find_by_sql "CALL topics(3);"
     assert_equal 3, topics.size
     assert @connection.active?, "Bad connection use by 'Mysql2Adapter.select'"
   end
diff --git a/activerecord/test/cases/adapters/mysql2/sql_types_test.rb b/activerecord/test/cases/adapters/mysql2/sql_types_test.rb
index 4926bc2267..e10642cbb4 100644
--- a/activerecord/test/cases/adapters/mysql2/sql_types_test.rb
+++ b/activerecord/test/cases/adapters/mysql2/sql_types_test.rb
@@ -1,14 +1,16 @@
+# frozen_string_literal: true
+
 require "cases/helper"
 
 class Mysql2SqlTypesTest < ActiveRecord::Mysql2TestCase
   def test_binary_types
-    assert_equal 'varbinary(64)', type_to_sql(:binary, 64)
-    assert_equal 'varbinary(4095)', type_to_sql(:binary, 4095)
-    assert_equal 'blob', type_to_sql(:binary, 4096)
-    assert_equal 'blob', type_to_sql(:binary)
+    assert_equal "varbinary(64)", type_to_sql(:binary, 64)
+    assert_equal "varbinary(4095)", type_to_sql(:binary, 4095)
+    assert_equal "blob", type_to_sql(:binary, 4096)
+    assert_equal "blob", type_to_sql(:binary)
   end
 
-  def type_to_sql(*args)
-    ActiveRecord::Base.connection.type_to_sql(*args)
+  def type_to_sql(type, limit = nil)
+    ActiveRecord::Base.connection.type_to_sql(type, limit: limit)
   end
 end
diff --git a/activerecord/test/cases/adapters/mysql2/table_options_test.rb b/activerecord/test/cases/adapters/mysql2/table_options_test.rb
index af121ee7d9..1c92df940f 100644
--- a/activerecord/test/cases/adapters/mysql2/table_options_test.rb
+++ b/activerecord/test/cases/adapters/mysql2/table_options_test.rb
@@ -1,5 +1,7 @@
+# frozen_string_literal: true
+
 require "cases/helper"
-require 'support/schema_dumping_helper'
+require "support/schema_dumping_helper"
 
 class Mysql2TableOptionsTest < ActiveRecord::Mysql2TestCase
   include SchemaDumpingHelper
@@ -15,28 +17,103 @@ class Mysql2TableOptionsTest < ActiveRecord::Mysql2TestCase
   test "table options with ENGINE" do
     @connection.create_table "mysql_table_options", force: true, options: "ENGINE=MyISAM"
     output = dump_table_schema("mysql_table_options")
-    options = %r{create_table "mysql_table_options", force: :cascade, options: "(?<options>.*)"}.match(output)[:options]
+    options = %r{create_table "mysql_table_options", options: "(?<options>.*)"}.match(output)[:options]
     assert_match %r{ENGINE=MyISAM}, options
   end
 
   test "table options with ROW_FORMAT" do
     @connection.create_table "mysql_table_options", force: true, options: "ROW_FORMAT=REDUNDANT"
     output = dump_table_schema("mysql_table_options")
-    options = %r{create_table "mysql_table_options", force: :cascade, options: "(?<options>.*)"}.match(output)[:options]
+    options = %r{create_table "mysql_table_options", options: "(?<options>.*)"}.match(output)[:options]
     assert_match %r{ROW_FORMAT=REDUNDANT}, options
   end
 
   test "table options with CHARSET" do
     @connection.create_table "mysql_table_options", force: true, options: "CHARSET=utf8mb4"
     output = dump_table_schema("mysql_table_options")
-    options = %r{create_table "mysql_table_options", force: :cascade, options: "(?<options>.*)"}.match(output)[:options]
+    options = %r{create_table "mysql_table_options", options: "(?<options>.*)"}.match(output)[:options]
     assert_match %r{CHARSET=utf8mb4}, options
   end
 
   test "table options with COLLATE" do
     @connection.create_table "mysql_table_options", force: true, options: "COLLATE=utf8mb4_bin"
     output = dump_table_schema("mysql_table_options")
-    options = %r{create_table "mysql_table_options", force: :cascade, options: "(?<options>.*)"}.match(output)[:options]
+    options = %r{create_table "mysql_table_options", options: "(?<options>.*)"}.match(output)[:options]
     assert_match %r{COLLATE=utf8mb4_bin}, options
   end
 end
+
+class Mysql2DefaultEngineOptionSchemaDumpTest < ActiveRecord::Mysql2TestCase
+  include SchemaDumpingHelper
+  self.use_transactional_tests = false
+
+  def setup
+    @verbose_was = ActiveRecord::Migration.verbose
+    ActiveRecord::Migration.verbose = false
+  end
+
+  def teardown
+    ActiveRecord::Base.connection.drop_table "mysql_table_options", if_exists: true
+    ActiveRecord::Migration.verbose = @verbose_was
+    ActiveRecord::SchemaMigration.delete_all rescue nil
+  end
+
+  test "schema dump includes ENGINE=InnoDB if not provided" do
+    ActiveRecord::Base.connection.create_table "mysql_table_options", force: true
+
+    output  = dump_table_schema("mysql_table_options")
+    options = %r{create_table "mysql_table_options", options: "(?<options>.*)"}.match(output)[:options]
+    assert_match %r{ENGINE=InnoDB}, options
+  end
+
+  test "schema dump includes ENGINE=InnoDB in legacy migrations" do
+    migration = Class.new(ActiveRecord::Migration[5.1]) do
+      def migrate(x)
+        create_table "mysql_table_options", force: true
+      end
+    end.new
+
+    ActiveRecord::Migrator.new(:up, [migration]).migrate
+
+    output  = dump_table_schema("mysql_table_options")
+    options = %r{create_table "mysql_table_options", options: "(?<options>.*)"}.match(output)[:options]
+    assert_match %r{ENGINE=InnoDB}, options
+  end
+end
+
+class Mysql2DefaultEngineOptionSqlOutputTest < ActiveRecord::Mysql2TestCase
+  self.use_transactional_tests = false
+
+  def setup
+    @logger_was  = ActiveRecord::Base.logger
+    @log         = StringIO.new
+    @verbose_was = ActiveRecord::Migration.verbose
+    ActiveRecord::Base.logger = ActiveSupport::Logger.new(@log)
+    ActiveRecord::Migration.verbose = false
+  end
+
+  def teardown
+    ActiveRecord::Base.logger       = @logger_was
+    ActiveRecord::Migration.verbose = @verbose_was
+    ActiveRecord::Base.connection.drop_table "mysql_table_options", if_exists: true
+    ActiveRecord::SchemaMigration.delete_all rescue nil
+  end
+
+  test "new migrations do not contain default ENGINE=InnoDB option" do
+    ActiveRecord::Base.connection.create_table "mysql_table_options", force: true
+
+    assert_no_match %r{ENGINE=InnoDB}, @log.string
+  end
+
+  test "legacy migrations contain default ENGINE=InnoDB option" do
+    migration = Class.new(ActiveRecord::Migration[5.1]) do
+      def migrate(x)
+        create_table "mysql_table_options", force: true
+      end
+    end.new
+
+    ActiveRecord::Migrator.new(:up, [migration]).migrate
+
+    assert_match %r{ENGINE=InnoDB}, @log.string
+  end
+end
diff --git a/activerecord/test/cases/adapters/mysql2/transaction_test.rb b/activerecord/test/cases/adapters/mysql2/transaction_test.rb
index 0e37c70e5c..f921515c10 100644
--- a/activerecord/test/cases/adapters/mysql2/transaction_test.rb
+++ b/activerecord/test/cases/adapters/mysql2/transaction_test.rb
@@ -1,22 +1,27 @@
+# frozen_string_literal: true
+
 require "cases/helper"
-require 'support/connection_helper'
+require "support/connection_helper"
 
 module ActiveRecord
   class Mysql2TransactionTest < ActiveRecord::Mysql2TestCase
     self.use_transactional_tests = false
 
     class Sample < ActiveRecord::Base
-      self.table_name = 'samples'
+      self.table_name = "samples"
     end
 
     setup do
+      @abort, Thread.abort_on_exception = Thread.abort_on_exception, false
+      Thread.report_on_exception, @original_report_on_exception = false, Thread.report_on_exception if Thread.respond_to?(:report_on_exception)
+
       @connection = ActiveRecord::Base.connection
       @connection.clear_cache!
 
       @connection.transaction do
-        @connection.drop_table 'samples', if_exists: true
-        @connection.create_table('samples') do |t|
-          t.integer 'value'
+        @connection.drop_table "samples", if_exists: true
+        @connection.create_table("samples") do |t|
+          t.integer "value"
         end
       end
 
@@ -24,38 +29,120 @@ module ActiveRecord
     end
 
     teardown do
-      @connection.drop_table 'samples', if_exists: true
+      @connection.drop_table "samples", if_exists: true
+
+      Thread.abort_on_exception = @abort
+      Thread.report_on_exception = @original_report_on_exception if Thread.respond_to?(:report_on_exception)
     end
 
-    test "raises error when a serialization failure occurs" do
-      assert_raises(ActiveRecord::TransactionSerializationError) do
+    test "raises Deadlocked when a deadlock is encountered" do
+      assert_raises(ActiveRecord::Deadlocked) do
+        barrier = Concurrent::CyclicBarrier.new(2)
+
+        s1 = Sample.create value: 1
+        s2 = Sample.create value: 2
+
         thread = Thread.new do
-          Sample.transaction isolation: :serializable do
-            Sample.delete_all
+          Sample.transaction do
+            s1.lock!
+            barrier.wait
+            s2.update_attributes value: 1
+          end
+        end
 
-            10.times do |i|
-              sleep 0.1
+        begin
+          Sample.transaction do
+            s2.lock!
+            barrier.wait
+            s1.update_attributes value: 2
+          end
+        ensure
+          thread.join
+        end
+      end
+    end
 
-              Sample.create value: i
-            end
+    test "raises LockWaitTimeout when lock wait timeout exceeded" do
+      assert_raises(ActiveRecord::LockWaitTimeout) do
+        s = Sample.create!(value: 1)
+        latch1 = Concurrent::CountDownLatch.new
+        latch2 = Concurrent::CountDownLatch.new
+
+        thread = Thread.new do
+          Sample.transaction do
+            Sample.lock.find(s.id)
+            latch1.count_down
+            latch2.wait
           end
         end
 
-        sleep 0.1
+        begin
+          Sample.transaction do
+            latch1.wait
+            Sample.connection.execute("SET innodb_lock_wait_timeout = 1")
+            Sample.lock.find(s.id)
+          end
+        ensure
+          Sample.connection.execute("SET innodb_lock_wait_timeout = DEFAULT")
+          latch2.count_down
+          thread.join
+        end
+      end
+    end
 
-        Sample.transaction isolation: :serializable do
-          Sample.delete_all
+    test "raises StatementTimeout when statement timeout exceeded" do
+      skip unless ActiveRecord::Base.connection.show_variable("max_execution_time")
+      assert_raises(ActiveRecord::StatementTimeout) do
+        s = Sample.create!(value: 1)
+        latch1 = Concurrent::CountDownLatch.new
+        latch2 = Concurrent::CountDownLatch.new
 
-          10.times do |i|
-            sleep 0.1
+        thread = Thread.new do
+          Sample.transaction do
+            Sample.lock.find(s.id)
+            latch1.count_down
+            latch2.wait
+          end
+        end
 
-            Sample.create value: i
+        begin
+          Sample.transaction do
+            latch1.wait
+            Sample.connection.execute("SET max_execution_time = 1")
+            Sample.lock.find(s.id)
           end
+        ensure
+          Sample.connection.execute("SET max_execution_time = DEFAULT")
+          latch2.count_down
+          thread.join
+        end
+      end
+    end
 
-          sleep 1
+    test "raises QueryCanceled when canceling statement due to user request" do
+      assert_raises(ActiveRecord::QueryCanceled) do
+        s = Sample.create!(value: 1)
+        latch = Concurrent::CountDownLatch.new
+
+        thread = Thread.new do
+          Sample.transaction do
+            Sample.lock.find(s.id)
+            latch.count_down
+            sleep(0.5)
+            conn = Sample.connection
+            pid = conn.query_value("SELECT id FROM information_schema.processlist WHERE info LIKE '% FOR UPDATE'")
+            conn.execute("KILL QUERY #{pid}")
+          end
         end
 
-        thread.join
+        begin
+          Sample.transaction do
+            latch.wait
+            Sample.lock.find(s.id)
+          end
+        ensure
+          thread.join
+        end
       end
     end
   end
diff --git a/activerecord/test/cases/adapters/mysql2/unsigned_type_test.rb b/activerecord/test/cases/adapters/mysql2/unsigned_type_test.rb
index 3df11ce11b..b01f5d7f5a 100644
--- a/activerecord/test/cases/adapters/mysql2/unsigned_type_test.rb
+++ b/activerecord/test/cases/adapters/mysql2/unsigned_type_test.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require "cases/helper"
 require "support/schema_dumping_helper"
 
@@ -15,6 +17,7 @@ class Mysql2UnsignedTypeTest < ActiveRecord::Mysql2TestCase
       t.bigint  :unsigned_bigint,  unsigned: true
       t.float   :unsigned_float,   unsigned: true
       t.decimal :unsigned_decimal, unsigned: true, precision: 10, scale: 2
+      t.column  :unsigned_zerofill, "int unsigned zerofill"
     end
   end
 
@@ -34,10 +37,10 @@ class Mysql2UnsignedTypeTest < ActiveRecord::Mysql2TestCase
     assert_raise(ActiveModel::RangeError) do
       UnsignedType.create(unsigned_bigint: -10)
     end
-    assert_raise(ActiveRecord::StatementInvalid) do
+    assert_raise(ActiveRecord::RangeError) do
       UnsignedType.create(unsigned_float: -10.0)
     end
-    assert_raise(ActiveRecord::StatementInvalid) do
+    assert_raise(ActiveRecord::RangeError) do
       UnsignedType.create(unsigned_decimal: -10.0)
     end
   end
@@ -50,16 +53,16 @@ class Mysql2UnsignedTypeTest < ActiveRecord::Mysql2TestCase
       t.unsigned_decimal :unsigned_decimal_t, precision: 10, scale: 2
     end
 
-    @connection.columns("unsigned_types").select { |c| /^unsigned_/ === c.name }.each do |column|
+    @connection.columns("unsigned_types").select { |c| /^unsigned_/.match?(c.name) }.each do |column|
       assert column.unsigned?
     end
   end
 
   test "schema dump includes unsigned option" do
     schema = dump_table_schema "unsigned_types"
-    assert_match %r{t.integer\s+"unsigned_integer",\s+unsigned: true$}, schema
-    assert_match %r{t.bigint\s+"unsigned_bigint",\s+unsigned: true$}, schema
-    assert_match %r{t.float\s+"unsigned_float",\s+limit: 24,\s+unsigned: true$}, schema
-    assert_match %r{t.decimal\s+"unsigned_decimal",\s+precision: 10,\s+scale: 2,\s+unsigned: true$}, schema
+    assert_match %r{t\.integer\s+"unsigned_integer",\s+unsigned: true$}, schema
+    assert_match %r{t\.bigint\s+"unsigned_bigint",\s+unsigned: true$}, schema
+    assert_match %r{t\.float\s+"unsigned_float",\s+unsigned: true$}, schema
+    assert_match %r{t\.decimal\s+"unsigned_decimal",\s+precision: 10,\s+scale: 2,\s+unsigned: true$}, schema
   end
 end
diff --git a/activerecord/test/cases/adapters/mysql2/virtual_column_test.rb b/activerecord/test/cases/adapters/mysql2/virtual_column_test.rb
new file mode 100644
index 0000000000..ffde8ed4d8
--- /dev/null
+++ b/activerecord/test/cases/adapters/mysql2/virtual_column_test.rb
@@ -0,0 +1,61 @@
+# frozen_string_literal: true
+
+require "cases/helper"
+require "support/schema_dumping_helper"
+
+if ActiveRecord::Base.connection.supports_virtual_columns?
+  class Mysql2VirtualColumnTest < ActiveRecord::Mysql2TestCase
+    include SchemaDumpingHelper
+
+    self.use_transactional_tests = false
+
+    class VirtualColumn < ActiveRecord::Base
+    end
+
+    def setup
+      @connection = ActiveRecord::Base.connection
+      @connection.create_table :virtual_columns, force: true do |t|
+        t.string  :name
+        t.virtual :upper_name,  type: :string,  as: "UPPER(`name`)"
+        t.virtual :name_length, type: :integer, as: "LENGTH(`name`)", stored: true
+      end
+      VirtualColumn.create(name: "Rails")
+    end
+
+    def teardown
+      @connection.drop_table :virtual_columns, if_exists: true
+      VirtualColumn.reset_column_information
+    end
+
+    def test_virtual_column
+      column = VirtualColumn.columns_hash["upper_name"]
+      assert_predicate column, :virtual?
+      assert_match %r{\bVIRTUAL\b}, column.extra
+      assert_equal "RAILS", VirtualColumn.take.upper_name
+    end
+
+    def test_stored_column
+      column = VirtualColumn.columns_hash["name_length"]
+      assert_predicate column, :virtual?
+      assert_match %r{\b(?:STORED|PERSISTENT)\b}, column.extra
+      assert_equal 5, VirtualColumn.take.name_length
+    end
+
+    def test_change_table
+      @connection.change_table :virtual_columns do |t|
+        t.virtual :lower_name, type: :string, as: "LOWER(name)"
+      end
+      VirtualColumn.reset_column_information
+      column = VirtualColumn.columns_hash["lower_name"]
+      assert_predicate column, :virtual?
+      assert_match %r{\bVIRTUAL\b}, column.extra
+      assert_equal "rails", VirtualColumn.take.lower_name
+    end
+
+    def test_schema_dumping
+      output = dump_table_schema("virtual_columns")
+      assert_match(/t\.virtual\s+"upper_name",\s+type: :string,\s+as: "(?:UPPER|UCASE)\(`name`\)"$/i, output)
+      assert_match(/t\.virtual\s+"name_length",\s+type: :integer,\s+as: "LENGTH\(`name`\)",\s+stored: true$/i, output)
+    end
+  end
+end
diff --git a/activerecord/test/cases/adapters/postgresql/active_schema_test.rb b/activerecord/test/cases/adapters/postgresql/active_schema_test.rb
index 439e2ce6f7..99c53dadeb 100644
--- a/activerecord/test/cases/adapters/postgresql/active_schema_test.rb
+++ b/activerecord/test/cases/adapters/postgresql/active_schema_test.rb
@@ -1,4 +1,6 @@
-require 'cases/helper'
+# frozen_string_literal: true
+
+require "cases/helper"
 
 class PostgresqlActiveSchemaTest < ActiveRecord::PostgreSQLTestCase
   def setup
@@ -15,12 +17,12 @@ class PostgresqlActiveSchemaTest < ActiveRecord::PostgreSQLTestCase
 
   def test_create_database_with_encoding
     assert_equal %(CREATE DATABASE "matt" ENCODING = 'utf8'), create_database(:matt)
-    assert_equal %(CREATE DATABASE "aimonetti" ENCODING = 'latin1'), create_database(:aimonetti, :encoding => :latin1)
-    assert_equal %(CREATE DATABASE "aimonetti" ENCODING = 'latin1'), create_database(:aimonetti, 'encoding' => :latin1)
+    assert_equal %(CREATE DATABASE "aimonetti" ENCODING = 'latin1'), create_database(:aimonetti, encoding: :latin1)
+    assert_equal %(CREATE DATABASE "aimonetti" ENCODING = 'latin1'), create_database(:aimonetti, "encoding" => :latin1)
   end
 
   def test_create_database_with_collation_and_ctype
-    assert_equal %(CREATE DATABASE "aimonetti" ENCODING = 'UTF8' LC_COLLATE = 'ja_JP.UTF8' LC_CTYPE = 'ja_JP.UTF8'), create_database(:aimonetti, :encoding => :"UTF8", :collation => :"ja_JP.UTF8", :ctype => :"ja_JP.UTF8")
+    assert_equal %(CREATE DATABASE "aimonetti" ENCODING = 'UTF8' LC_COLLATE = 'ja_JP.UTF8' LC_CTYPE = 'ja_JP.UTF8'), create_database(:aimonetti, encoding: :"UTF8", collation: :"ja_JP.UTF8", ctype: :"ja_JP.UTF8")
   end
 
   def test_add_index
@@ -31,14 +33,18 @@ class PostgresqlActiveSchemaTest < ActiveRecord::PostgreSQLTestCase
     assert_equal expected, add_index(:people, :last_name, unique: true, where: "state = 'active'")
 
     expected = %(CREATE UNIQUE INDEX  "index_people_on_lower_last_name" ON "people"  (lower(last_name)))
-    assert_equal expected, add_index(:people, 'lower(last_name)', unique: true)
+    assert_equal expected, add_index(:people, "lower(last_name)", unique: true)
 
     expected = %(CREATE UNIQUE INDEX  "index_people_on_last_name_varchar_pattern_ops" ON "people"  (last_name varchar_pattern_ops))
-    assert_equal expected, add_index(:people, 'last_name varchar_pattern_ops', unique: true)
+    assert_equal expected, add_index(:people, "last_name varchar_pattern_ops", unique: true)
 
     expected = %(CREATE  INDEX CONCURRENTLY "index_people_on_last_name" ON "people"  ("last_name"))
     assert_equal expected, add_index(:people, :last_name, algorithm: :concurrently)
 
+    expected = %(CREATE  INDEX  "index_people_on_last_name_and_first_name" ON "people"  ("last_name" DESC, "first_name" ASC))
+    assert_equal expected, add_index(:people, [:last_name, :first_name], order: { last_name: :desc, first_name: :asc })
+    assert_equal expected, add_index(:people, ["last_name", :first_name], order: { last_name: :desc, "first_name" => :asc })
+
     %w(gin gist hash btree).each do |type|
       expected = %(CREATE  INDEX  "index_people_on_last_name" ON "people" USING #{type} ("last_name"))
       assert_equal expected, add_index(:people, :last_name, using: type)
@@ -50,9 +56,12 @@ class PostgresqlActiveSchemaTest < ActiveRecord::PostgreSQLTestCase
       assert_equal expected, add_index(:people, :last_name, using: type, unique: true, where: "state = 'active'")
 
       expected = %(CREATE UNIQUE INDEX  "index_people_on_lower_last_name" ON "people" USING #{type} (lower(last_name)))
-      assert_equal expected, add_index(:people, 'lower(last_name)', using: type, unique: true)
+      assert_equal expected, add_index(:people, "lower(last_name)", using: type, unique: true)
     end
 
+    expected = %(CREATE  INDEX  "index_people_on_last_name" ON "people" USING gist ("last_name" bpchar_pattern_ops))
+    assert_equal expected, add_index(:people, :last_name, using: :gist, opclass: { last_name: :bpchar_pattern_ops })
+
     assert_raise ArgumentError do
       add_index(:people, :last_name, algorithm: :copy)
     end
@@ -63,7 +72,7 @@ class PostgresqlActiveSchemaTest < ActiveRecord::PostgreSQLTestCase
   def test_remove_index
     # remove_index calls index_name_for_remove which can't work since execute is stubbed
     ActiveRecord::ConnectionAdapters::PostgreSQLAdapter.send(:define_method, :index_name_for_remove) do |*|
-      'index_people_on_last_name'
+      "index_people_on_last_name"
     end
 
     expected = %(DROP INDEX CONCURRENTLY "index_people_on_last_name")
@@ -81,6 +90,12 @@ class PostgresqlActiveSchemaTest < ActiveRecord::PostgreSQLTestCase
     assert_equal expected, remove_index(:people, name: "index_people_on_last_name", algorithm: :concurrently)
   end
 
+  def test_remove_index_with_wrong_option
+    assert_raises ArgumentError do
+      remove_index(:people, coulmn: :last_name)
+    end
+  end
+
   private
     def method_missing(method_symbol, *arguments)
       ActiveRecord::Base.connection.send(method_symbol, *arguments)
diff --git a/activerecord/test/cases/adapters/postgresql/array_test.rb b/activerecord/test/cases/adapters/postgresql/array_test.rb
index 380a90d765..0e9e86f425 100644
--- a/activerecord/test/cases/adapters/postgresql/array_test.rb
+++ b/activerecord/test/cases/adapters/postgresql/array_test.rb
@@ -1,63 +1,100 @@
+# frozen_string_literal: true
+
 require "cases/helper"
-require 'support/schema_dumping_helper'
+require "support/schema_dumping_helper"
 
 class PostgresqlArrayTest < ActiveRecord::PostgreSQLTestCase
   include SchemaDumpingHelper
   include InTimeZone
 
   class PgArray < ActiveRecord::Base
-    self.table_name = 'pg_arrays'
+    self.table_name = "pg_arrays"
   end
 
   def setup
     @connection = ActiveRecord::Base.connection
 
-    enable_extension!('hstore', @connection)
+    enable_extension!("hstore", @connection)
 
     @connection.transaction do
-      @connection.create_table('pg_arrays') do |t|
-        t.string 'tags', array: true
-        t.integer 'ratings', array: true
+      @connection.create_table("pg_arrays") do |t|
+        t.string "tags", array: true, limit: 255
+        t.integer "ratings", array: true
         t.datetime :datetimes, array: true
         t.hstore :hstores, array: true
+        t.decimal :decimals, array: true, default: [], precision: 10, scale: 2
+        t.timestamp :timestamps, array: true, default: [], precision: 6
       end
     end
     PgArray.reset_column_information
-    @column = PgArray.columns_hash['tags']
+    @column = PgArray.columns_hash["tags"]
     @type = PgArray.type_for_attribute("tags")
   end
 
   teardown do
-    @connection.drop_table 'pg_arrays', if_exists: true
-    disable_extension!('hstore', @connection)
+    @connection.drop_table "pg_arrays", if_exists: true
+    disable_extension!("hstore", @connection)
   end
 
   def test_column
     assert_equal :string, @column.type
-    assert_equal "character varying", @column.sql_type
+    assert_equal "character varying(255)", @column.sql_type
     assert @column.array?
     assert_not @type.binary?
 
-    ratings_column = PgArray.columns_hash['ratings']
+    ratings_column = PgArray.columns_hash["ratings"]
     assert_equal :integer, ratings_column.type
     assert ratings_column.array?
   end
 
+  def test_not_compatible_with_serialize_array
+    new_klass = Class.new(PgArray) do
+      serialize :tags, Array
+    end
+    assert_raises(ActiveRecord::AttributeMethods::Serialization::ColumnNotSerializableError) do
+      new_klass.new
+    end
+  end
+
+  class MyTags
+    def initialize(tags); @tags = tags end
+    def to_a; @tags end
+    def self.load(tags); new(tags) end
+    def self.dump(object); object.to_a end
+  end
+
+  def test_array_with_serialized_attributes
+    new_klass = Class.new(PgArray) do
+      serialize :tags, MyTags
+    end
+
+    new_klass.create!(tags: MyTags.new(["one", "two"]))
+    record = new_klass.first
+
+    assert_instance_of MyTags, record.tags
+    assert_equal ["one", "two"], record.tags.to_a
+
+    record.tags = MyTags.new(["three", "four"])
+    record.save!
+
+    assert_equal ["three", "four"], record.reload.tags.to_a
+  end
+
   def test_default
-    @connection.add_column 'pg_arrays', 'score', :integer, array: true, default: [4, 4, 2]
+    @connection.add_column "pg_arrays", "score", :integer, array: true, default: [4, 4, 2]
     PgArray.reset_column_information
 
-    assert_equal([4, 4, 2], PgArray.column_defaults['score'])
+    assert_equal([4, 4, 2], PgArray.column_defaults["score"])
     assert_equal([4, 4, 2], PgArray.new.score)
   ensure
     PgArray.reset_column_information
   end
 
   def test_default_strings
-    @connection.add_column 'pg_arrays', 'names', :string, array: true, default: ["foo", "bar"]
+    @connection.add_column "pg_arrays", "names", :string, array: true, default: ["foo", "bar"]
     PgArray.reset_column_information
 
-    assert_equal(["foo", "bar"], PgArray.column_defaults['names'])
+    assert_equal(["foo", "bar"], PgArray.column_defaults["names"])
     assert_equal(["foo", "bar"], PgArray.new.names)
   ensure
     PgArray.reset_column_information
@@ -68,10 +105,10 @@ class PostgresqlArrayTest < ActiveRecord::PostgreSQLTestCase
     @connection.change_column :pg_arrays, :snippets, :text, array: true, default: []
 
     PgArray.reset_column_information
-    column = PgArray.columns_hash['snippets']
+    column = PgArray.columns_hash["snippets"]
 
     assert_equal :text, column.type
-    assert_equal [], PgArray.column_defaults['snippets']
+    assert_equal [], PgArray.column_defaults["snippets"]
     assert column.array?
   end
 
@@ -88,17 +125,17 @@ class PostgresqlArrayTest < ActiveRecord::PostgreSQLTestCase
     @connection.change_column_default :pg_arrays, :tags, []
 
     PgArray.reset_column_information
-    assert_equal [], PgArray.column_defaults['tags']
+    assert_equal [], PgArray.column_defaults["tags"]
   end
 
   def test_type_cast_array
-    assert_equal(['1', '2', '3'], @type.deserialize('{1,2,3}'))
-    assert_equal([], @type.deserialize('{}'))
-    assert_equal([nil], @type.deserialize('{NULL}'))
+    assert_equal(["1", "2", "3"], @type.deserialize("{1,2,3}"))
+    assert_equal([], @type.deserialize("{}"))
+    assert_equal([nil], @type.deserialize("{NULL}"))
   end
 
   def test_type_cast_integers
-    x = PgArray.new(ratings: ['1', '2'])
+    x = PgArray.new(ratings: ["1", "2"])
 
     assert_equal([1, 2], x.ratings)
 
@@ -110,22 +147,23 @@ class PostgresqlArrayTest < ActiveRecord::PostgreSQLTestCase
 
   def test_schema_dump_with_shorthand
     output = dump_table_schema "pg_arrays"
-    assert_match %r[t\.string\s+"tags",\s+array: true], output
+    assert_match %r[t\.string\s+"tags",\s+limit: 255,\s+array: true], output
     assert_match %r[t\.integer\s+"ratings",\s+array: true], output
+    assert_match %r[t\.decimal\s+"decimals",\s+precision: 10,\s+scale: 2,\s+default: \[\],\s+array: true], output
   end
 
   def test_select_with_strings
     @connection.execute "insert into pg_arrays (tags) VALUES ('{1,2,3}')"
     x = PgArray.first
-    assert_equal(['1','2','3'], x.tags)
+    assert_equal(["1", "2", "3"], x.tags)
   end
 
   def test_rewrite_with_strings
     @connection.execute "insert into pg_arrays (tags) VALUES ('{1,2,3}')"
     x = PgArray.first
-    x.tags = ['1','2','3','4']
+    x.tags = ["1", "2", "3", "4"]
     x.save!
-    assert_equal ['1','2','3','4'], x.reload.tags
+    assert_equal ["1", "2", "3", "4"], x.reload.tags
   end
 
   def test_select_with_integers
@@ -137,25 +175,25 @@ class PostgresqlArrayTest < ActiveRecord::PostgreSQLTestCase
   def test_rewrite_with_integers
     @connection.execute "insert into pg_arrays (ratings) VALUES ('{1,2,3}')"
     x = PgArray.first
-    x.ratings = [2, '3', 4]
+    x.ratings = [2, "3", 4]
     x.save!
     assert_equal [2, 3, 4], x.reload.ratings
   end
 
   def test_multi_dimensional_with_strings
-    assert_cycle(:tags, [[['1'], ['2']], [['2'], ['3']]])
+    assert_cycle(:tags, [[["1"], ["2"]], [["2"], ["3"]]])
   end
 
   def test_with_empty_strings
-    assert_cycle(:tags, [ '1', '2', '', '4', '', '5' ])
+    assert_cycle(:tags, [ "1", "2", "", "4", "", "5" ])
   end
 
   def test_with_multi_dimensional_empty_strings
-    assert_cycle(:tags, [[['1', '2'], ['', '4'], ['', '5']]])
+    assert_cycle(:tags, [[["1", "2"], ["", "4"], ["", "5"]]])
   end
 
   def test_with_arbitrary_whitespace
-    assert_cycle(:tags, [[['1', '2'], ['    ', '4'], ['    ', '5']]])
+    assert_cycle(:tags, [[["1", "2"], ["    ", "4"], ["    ", "5"]]])
   end
 
   def test_multi_dimensional_with_integers
@@ -163,34 +201,45 @@ class PostgresqlArrayTest < ActiveRecord::PostgreSQLTestCase
   end
 
   def test_strings_with_quotes
-    assert_cycle(:tags, ['this has','some "s that need to be escaped"'])
+    assert_cycle(:tags, ["this has", 'some "s that need to be escaped"'])
   end
 
   def test_strings_with_commas
-    assert_cycle(:tags, ['this,has','many,values'])
+    assert_cycle(:tags, ["this,has", "many,values"])
   end
 
   def test_strings_with_array_delimiters
-    assert_cycle(:tags, ['{','}'])
+    assert_cycle(:tags, ["{", "}"])
   end
 
   def test_strings_with_null_strings
-    assert_cycle(:tags, ['NULL','NULL'])
+    assert_cycle(:tags, ["NULL", "NULL"])
   end
 
   def test_contains_nils
-    assert_cycle(:tags, ['1',nil,nil])
+    assert_cycle(:tags, ["1", nil, nil])
   end
 
   def test_insert_fixture
     tag_values = ["val1", "val2", "val3_with_'_multiple_quote_'_chars"]
-    @connection.insert_fixture({"tags" => tag_values}, "pg_arrays" )
+    @connection.insert_fixture({ "tags" => tag_values }, "pg_arrays")
+    assert_equal(PgArray.last.tags, tag_values)
+  end
+
+  def test_insert_fixtures
+    tag_values = ["val1", "val2", "val3_with_'_multiple_quote_'_chars"]
+    @connection.insert_fixtures([{ "tags" => tag_values }], "pg_arrays")
     assert_equal(PgArray.last.tags, tag_values)
   end
 
   def test_attribute_for_inspect_for_array_field
+    record = PgArray.new { |a| a.ratings = (1..10).to_a }
+    assert_equal("[1, 2, 3, 4, 5, 6, 7, 8, 9, 10]", record.attribute_for_inspect(:ratings))
+  end
+
+  def test_attribute_for_inspect_for_array_field_for_large_array
     record = PgArray.new { |a| a.ratings = (1..11).to_a }
-    assert_equal("[1, 2, 3, 4, 5, 6, 7, 8, 9, 10, ...]", record.attribute_for_inspect(:ratings))
+    assert_equal("[1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11]", record.attribute_for_inspect(:ratings))
   end
 
   def test_escaping
@@ -206,17 +255,18 @@ class PostgresqlArrayTest < ActiveRecord::PostgreSQLTestCase
     x = PgArray.create!(tags: tags)
     x.reload
 
-    assert_equal x.tags_before_type_cast, PgArray.type_for_attribute('tags').serialize(tags)
+    refute x.changed?
   end
 
   def test_quoting_non_standard_delimiters
     strings = ["hello,", "world;"]
     oid = ActiveRecord::ConnectionAdapters::PostgreSQL::OID
-    comma_delim = oid::Array.new(ActiveRecord::Type::String.new, ',')
-    semicolon_delim = oid::Array.new(ActiveRecord::Type::String.new, ';')
+    comma_delim = oid::Array.new(ActiveRecord::Type::String.new, ",")
+    semicolon_delim = oid::Array.new(ActiveRecord::Type::String.new, ";")
+    conn = PgArray.connection
 
-    assert_equal %({"hello,",world;}), comma_delim.serialize(strings)
-    assert_equal %({hello,;"world;"}), semicolon_delim.serialize(strings)
+    assert_equal %({"hello,",world;}), conn.type_cast(comma_delim.serialize(strings))
+    assert_equal %({hello,;"world;"}), conn.type_cast(semicolon_delim.serialize(strings))
   end
 
   def test_mutate_array
@@ -231,13 +281,13 @@ class PostgresqlArrayTest < ActiveRecord::PostgreSQLTestCase
   end
 
   def test_mutate_value_in_array
-    x = PgArray.create!(hstores: [{ a: 'a' }, { b: 'b' }])
+    x = PgArray.create!(hstores: [{ a: "a" }, { b: "b" }])
 
-    x.hstores.first['a'] = 'c'
+    x.hstores.first["a"] = "c"
     x.save!
     x.reload
 
-    assert_equal [{ 'a' => 'c' }, { 'b' => 'b' }], x.hstores
+    assert_equal [{ "a" => "c" }, { "b" => "b" }], x.hstores
     assert_not x.changed?
   end
 
@@ -285,6 +335,12 @@ class PostgresqlArrayTest < ActiveRecord::PostgreSQLTestCase
     assert_equal record.tags, record.reload.tags
   end
 
+  def test_where_by_attribute_with_array
+    tags = ["black", "blue"]
+    record = PgArray.create!(tags: tags)
+    assert_equal record, PgArray.where(tags: tags).take
+  end
+
   def test_uniqueness_validation
     klass = Class.new(PgArray) do
       validates_uniqueness_of :tags
@@ -300,18 +356,33 @@ class PostgresqlArrayTest < ActiveRecord::PostgreSQLTestCase
     assert_equal ["has already been taken"], e2.errors[:tags], "Should have uniqueness message for tags"
   end
 
-  private
-  def assert_cycle field, array
-    # test creation
-    x = PgArray.create!(field => array)
-    x.reload
-    assert_equal(array, x.public_send(field))
+  def test_encoding_arrays_of_utf8_strings
+    arrays_of_utf8_strings = %w(nový ファイル)
+    assert_equal arrays_of_utf8_strings, @type.deserialize(@type.serialize(arrays_of_utf8_strings))
+    assert_equal [arrays_of_utf8_strings], @type.deserialize(@type.serialize([arrays_of_utf8_strings]))
+  end
 
-    # test updating
-    x = PgArray.create!(field => [])
-    x.public_send("#{field}=", array)
-    x.save!
-    x.reload
-    assert_equal(array, x.public_send(field))
+  def test_precision_is_respected_on_timestamp_columns
+    time = Time.now.change(usec: 123)
+    record = PgArray.create!(timestamps: [time])
+
+    assert_equal 123, record.timestamps.first.usec
+    record.reload
+    assert_equal 123, record.timestamps.first.usec
   end
+
+  private
+    def assert_cycle(field, array)
+      # test creation
+      x = PgArray.create!(field => array)
+      x.reload
+      assert_equal(array, x.public_send(field))
+
+      # test updating
+      x = PgArray.create!(field => [])
+      x.public_send("#{field}=", array)
+      x.save!
+      x.reload
+      assert_equal(array, x.public_send(field))
+    end
 end
diff --git a/activerecord/test/cases/adapters/postgresql/bit_string_test.rb b/activerecord/test/cases/adapters/postgresql/bit_string_test.rb
index cec6081aec..df04299569 100644
--- a/activerecord/test/cases/adapters/postgresql/bit_string_test.rb
+++ b/activerecord/test/cases/adapters/postgresql/bit_string_test.rb
@@ -1,6 +1,8 @@
+# frozen_string_literal: true
+
 require "cases/helper"
-require 'support/connection_helper'
-require 'support/schema_dumping_helper'
+require "support/connection_helper"
+require "support/schema_dumping_helper"
 
 class PostgresqlBitStringTest < ActiveRecord::PostgreSQLTestCase
   include ConnectionHelper
@@ -10,7 +12,7 @@ class PostgresqlBitStringTest < ActiveRecord::PostgreSQLTestCase
 
   def setup
     @connection = ActiveRecord::Base.connection
-    @connection.create_table('postgresql_bit_strings', :force => true) do |t|
+    @connection.create_table("postgresql_bit_strings", force: true) do |t|
       t.bit :a_bit, default: "00000011", limit: 8
       t.bit_varying :a_bit_varying, default: "0011", limit: 4
       t.bit :another_bit
@@ -20,7 +22,7 @@ class PostgresqlBitStringTest < ActiveRecord::PostgreSQLTestCase
 
   def teardown
     return unless @connection
-    @connection.drop_table 'postgresql_bit_strings', if_exists: true
+    @connection.drop_table "postgresql_bit_strings", if_exists: true
   end
 
   def test_bit_string_column
@@ -44,10 +46,10 @@ class PostgresqlBitStringTest < ActiveRecord::PostgreSQLTestCase
   end
 
   def test_default
-    assert_equal "00000011", PostgresqlBitString.column_defaults['a_bit']
+    assert_equal "00000011", PostgresqlBitString.column_defaults["a_bit"]
     assert_equal "00000011", PostgresqlBitString.new.a_bit
 
-    assert_equal "0011", PostgresqlBitString.column_defaults['a_bit_varying']
+    assert_equal "0011", PostgresqlBitString.column_defaults["a_bit_varying"]
     assert_equal "0011", PostgresqlBitString.new.a_bit_varying
   end
 
@@ -65,10 +67,11 @@ class PostgresqlBitStringTest < ActiveRecord::PostgreSQLTestCase
   end
 
   def test_roundtrip
-    PostgresqlBitString.create! a_bit: "00001010", a_bit_varying: "0101"
-    record = PostgresqlBitString.first
+    record = PostgresqlBitString.create!(a_bit: "00001010", a_bit_varying: "0101")
     assert_equal "00001010", record.a_bit
     assert_equal "0101", record.a_bit_varying
+    assert_nil record.another_bit
+    assert_nil record.another_bit_varying
 
     record.a_bit = "11111111"
     record.a_bit_varying = "0xF"
diff --git a/activerecord/test/cases/adapters/postgresql/bytea_test.rb b/activerecord/test/cases/adapters/postgresql/bytea_test.rb
index 7adc070430..a6bee113ff 100644
--- a/activerecord/test/cases/adapters/postgresql/bytea_test.rb
+++ b/activerecord/test/cases/adapters/postgresql/bytea_test.rb
@@ -1,29 +1,31 @@
+# frozen_string_literal: true
+
 require "cases/helper"
-require 'support/schema_dumping_helper'
+require "support/schema_dumping_helper"
 
 class PostgresqlByteaTest < ActiveRecord::PostgreSQLTestCase
   include SchemaDumpingHelper
 
   class ByteaDataType < ActiveRecord::Base
-    self.table_name = 'bytea_data_type'
+    self.table_name = "bytea_data_type"
   end
 
   def setup
     @connection = ActiveRecord::Base.connection
     begin
       @connection.transaction do
-        @connection.create_table('bytea_data_type') do |t|
-          t.binary 'payload'
-          t.binary 'serialized'
+        @connection.create_table("bytea_data_type") do |t|
+          t.binary "payload"
+          t.binary "serialized"
         end
       end
     end
-    @column = ByteaDataType.columns_hash['payload']
+    @column = ByteaDataType.columns_hash["payload"]
     @type = ByteaDataType.type_for_attribute("payload")
   end
 
   teardown do
-    @connection.drop_table 'bytea_data_type', if_exists: true
+    @connection.drop_table "bytea_data_type", if_exists: true
   end
 
   def test_column
@@ -32,9 +34,9 @@ class PostgresqlByteaTest < ActiveRecord::PostgreSQLTestCase
   end
 
   def test_binary_columns_are_limitless_the_upper_limit_is_one_GB
-    assert_equal 'bytea', @connection.type_to_sql(:binary, 100_000)
+    assert_equal "bytea", @connection.type_to_sql(:binary, limit: 100_000)
     assert_raise ActiveRecord::ActiveRecordError do
-      @connection.type_to_sql :binary, 4294967295
+      @connection.type_to_sql(:binary, limit: 4294967295)
     end
   end
 
@@ -42,17 +44,17 @@ class PostgresqlByteaTest < ActiveRecord::PostgreSQLTestCase
     assert @column
 
     data = "\u001F\x8B"
-    assert_equal('UTF-8', data.encoding.name)
-    assert_equal('ASCII-8BIT', @type.deserialize(data).encoding.name)
+    assert_equal("UTF-8", data.encoding.name)
+    assert_equal("ASCII-8BIT", @type.deserialize(data).encoding.name)
   end
 
   def test_type_cast_binary_value
-    data = "\u001F\x8B".force_encoding("BINARY")
+    data = "\u001F\x8B".dup.force_encoding("BINARY")
     assert_equal(data, @type.deserialize(data))
   end
 
   def test_type_case_nil
-    assert_equal(nil, @type.deserialize(nil))
+    assert_nil(@type.deserialize(nil))
   end
 
   def test_read_value
@@ -66,7 +68,7 @@ class PostgresqlByteaTest < ActiveRecord::PostgreSQLTestCase
   def test_read_nil_value
     @connection.execute "insert into bytea_data_type (payload) VALUES (null)"
     record = ByteaDataType.first
-    assert_equal(nil, record.payload)
+    assert_nil(record.payload)
     record.delete
   end
 
@@ -88,14 +90,15 @@ class PostgresqlByteaTest < ActiveRecord::PostgreSQLTestCase
   def test_via_to_sql_with_complicating_connection
     Thread.new do
       other_conn = ActiveRecord::Base.connection
-      other_conn.execute('SET standard_conforming_strings = off')
+      other_conn.execute("SET standard_conforming_strings = off")
+      other_conn.execute("SET escape_string_warning = off")
     end.join
 
     test_via_to_sql
   end
 
   def test_write_binary
-    data = File.read(File.join(File.dirname(__FILE__), '..', '..', '..', 'assets', 'example.log'))
+    data = File.read(File.join(__dir__, "..", "..", "..", "assets", "example.log"))
     assert(data.size > 1)
     record = ByteaDataType.create(payload: data)
     assert_not record.new_record?
@@ -106,8 +109,8 @@ class PostgresqlByteaTest < ActiveRecord::PostgreSQLTestCase
   def test_write_nil
     record = ByteaDataType.create(payload: nil)
     assert_not record.new_record?
-    assert_equal(nil, record.payload)
-    assert_equal(nil, ByteaDataType.where(id: record.id).first.payload)
+    assert_nil(record.payload)
+    assert_nil(ByteaDataType.where(id: record.id).first.payload)
   end
 
   class Serializer
diff --git a/activerecord/test/cases/adapters/postgresql/case_insensitive_test.rb b/activerecord/test/cases/adapters/postgresql/case_insensitive_test.rb
new file mode 100644
index 0000000000..305e033642
--- /dev/null
+++ b/activerecord/test/cases/adapters/postgresql/case_insensitive_test.rb
@@ -0,0 +1,28 @@
+# frozen_string_literal: true
+
+require "cases/helper"
+
+class PostgresqlCaseInsensitiveTest < ActiveRecord::PostgreSQLTestCase
+  class Default < ActiveRecord::Base; end
+
+  def test_case_insensitiveness
+    connection = ActiveRecord::Base.connection
+    table = Default.arel_table
+
+    column = Default.columns_hash["char1"]
+    comparison = connection.case_insensitive_comparison table, :char1, column, nil
+    assert_match(/lower/i, comparison.to_sql)
+
+    column = Default.columns_hash["char2"]
+    comparison = connection.case_insensitive_comparison table, :char2, column, nil
+    assert_match(/lower/i, comparison.to_sql)
+
+    column = Default.columns_hash["char3"]
+    comparison = connection.case_insensitive_comparison table, :char3, column, nil
+    assert_match(/lower/i, comparison.to_sql)
+
+    column = Default.columns_hash["multiline_default"]
+    comparison = connection.case_insensitive_comparison table, :multiline_default, column, nil
+    assert_match(/lower/i, comparison.to_sql)
+  end
+end
diff --git a/activerecord/test/cases/adapters/postgresql/change_schema_test.rb b/activerecord/test/cases/adapters/postgresql/change_schema_test.rb
index bc12df668d..adf461a9cc 100644
--- a/activerecord/test/cases/adapters/postgresql/change_schema_test.rb
+++ b/activerecord/test/cases/adapters/postgresql/change_schema_test.rb
@@ -1,4 +1,6 @@
-require 'cases/helper'
+# frozen_string_literal: true
+
+require "cases/helper"
 
 module ActiveRecord
   class Migration
@@ -19,17 +21,17 @@ module ActiveRecord
 
       def test_change_string_to_date
         connection.change_column :strings, :somedate, :timestamp, using: 'CAST("somedate" AS timestamp)'
-        assert_equal :datetime, connection.columns(:strings).find { |c| c.name == 'somedate' }.type
+        assert_equal :datetime, connection.columns(:strings).find { |c| c.name == "somedate" }.type
       end
 
       def test_change_type_with_symbol
         connection.change_column :strings, :somedate, :timestamp, cast_as: :timestamp
-        assert_equal :datetime, connection.columns(:strings).find { |c| c.name == 'somedate' }.type
+        assert_equal :datetime, connection.columns(:strings).find { |c| c.name == "somedate" }.type
       end
 
       def test_change_type_with_array
         connection.change_column :strings, :somedate, :timestamp, array: true, cast_as: :timestamp
-        column = connection.columns(:strings).find { |c| c.name == 'somedate' }
+        column = connection.columns(:strings).find { |c| c.name == "somedate" }
         assert_equal :datetime, column.type
         assert column.array?
       end
diff --git a/activerecord/test/cases/adapters/postgresql/cidr_test.rb b/activerecord/test/cases/adapters/postgresql/cidr_test.rb
index 52f2a0096c..f20958fbd2 100644
--- a/activerecord/test/cases/adapters/postgresql/cidr_test.rb
+++ b/activerecord/test/cases/adapters/postgresql/cidr_test.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require "cases/helper"
 require "ipaddr"
 
diff --git a/activerecord/test/cases/adapters/postgresql/citext_test.rb b/activerecord/test/cases/adapters/postgresql/citext_test.rb
index bd62041e79..a25f102bad 100644
--- a/activerecord/test/cases/adapters/postgresql/citext_test.rb
+++ b/activerecord/test/cases/adapters/postgresql/citext_test.rb
@@ -1,78 +1,78 @@
-require 'cases/helper'
-require 'support/schema_dumping_helper'
-
-if ActiveRecord::Base.connection.supports_extensions?
-  class PostgresqlCitextTest < ActiveRecord::PostgreSQLTestCase
-    include SchemaDumpingHelper
-    class Citext < ActiveRecord::Base
-      self.table_name = 'citexts'
-    end
+# frozen_string_literal: true
 
-    def setup
-      @connection = ActiveRecord::Base.connection
+require "cases/helper"
+require "support/schema_dumping_helper"
 
-      enable_extension!('citext', @connection)
+class PostgresqlCitextTest < ActiveRecord::PostgreSQLTestCase
+  include SchemaDumpingHelper
+  class Citext < ActiveRecord::Base
+    self.table_name = "citexts"
+  end
 
-      @connection.create_table('citexts') do |t|
-        t.citext 'cival'
-      end
-    end
+  def setup
+    @connection = ActiveRecord::Base.connection
 
-    teardown do
-      @connection.drop_table 'citexts', if_exists: true
-      disable_extension!('citext', @connection)
-    end
+    enable_extension!("citext", @connection)
 
-    def test_citext_enabled
-      assert @connection.extension_enabled?('citext')
+    @connection.create_table("citexts") do |t|
+      t.citext "cival"
     end
+  end
 
-    def test_column
-      column = Citext.columns_hash['cival']
-      assert_equal :citext, column.type
-      assert_equal 'citext', column.sql_type
-      assert_not column.array?
+  teardown do
+    @connection.drop_table "citexts", if_exists: true
+    disable_extension!("citext", @connection)
+  end
 
-      type = Citext.type_for_attribute('cival')
-      assert_not type.binary?
-    end
+  def test_citext_enabled
+    assert @connection.extension_enabled?("citext")
+  end
 
-    def test_change_table_supports_json
-      @connection.transaction do
-        @connection.change_table('citexts') do |t|
-          t.citext 'username'
-        end
-        Citext.reset_column_information
-        column = Citext.columns_hash['username']
-        assert_equal :citext, column.type
+  def test_column
+    column = Citext.columns_hash["cival"]
+    assert_equal :citext, column.type
+    assert_equal "citext", column.sql_type
+    assert_not column.array?
 
-        raise ActiveRecord::Rollback # reset the schema change
+    type = Citext.type_for_attribute("cival")
+    assert_not type.binary?
+  end
+
+  def test_change_table_supports_json
+    @connection.transaction do
+      @connection.change_table("citexts") do |t|
+        t.citext "username"
       end
-    ensure
       Citext.reset_column_information
+      column = Citext.columns_hash["username"]
+      assert_equal :citext, column.type
+
+      raise ActiveRecord::Rollback # reset the schema change
     end
+  ensure
+    Citext.reset_column_information
+  end
 
-    def test_write
-      x = Citext.new(cival: 'Some CI Text')
-      x.save!
-      citext = Citext.first
-      assert_equal "Some CI Text", citext.cival
+  def test_write
+    x = Citext.new(cival: "Some CI Text")
+    x.save!
+    citext = Citext.first
+    assert_equal "Some CI Text", citext.cival
 
-      citext.cival = "Some NEW CI Text"
-      citext.save!
+    citext.cival = "Some NEW CI Text"
+    citext.save!
 
-      assert_equal "Some NEW CI Text", citext.reload.cival
-    end
+    assert_equal "Some NEW CI Text", citext.reload.cival
+  end
 
-    def test_select_case_insensitive
-      @connection.execute "insert into citexts (cival) values('Cased Text')"
-      x = Citext.where(cival: 'cased text').first
-      assert_equal 'Cased Text', x.cival
-    end
+  def test_select_case_insensitive
+    @connection.execute "insert into citexts (cival) values('Cased Text')"
+    x = Citext.where(cival: "cased text").first
+    assert_equal "Cased Text", x.cival
+  end
 
-    def test_schema_dump_with_shorthand
-      output = dump_table_schema("citexts")
-      assert_match %r[t\.citext "cival"], output
-    end
+  def test_schema_dump_with_shorthand
+    output = dump_table_schema("citexts")
+    assert_match %r[t\.citext "cival"], output
   end
 end
diff --git a/activerecord/test/cases/adapters/postgresql/collation_test.rb b/activerecord/test/cases/adapters/postgresql/collation_test.rb
index 8470329c35..7468f4c4f8 100644
--- a/activerecord/test/cases/adapters/postgresql/collation_test.rb
+++ b/activerecord/test/cases/adapters/postgresql/collation_test.rb
@@ -1,5 +1,7 @@
+# frozen_string_literal: true
+
 require "cases/helper"
-require 'support/schema_dumping_helper'
+require "support/schema_dumping_helper"
 
 class PostgresqlCollationTest < ActiveRecord::PostgreSQLTestCase
   include SchemaDumpingHelper
@@ -7,8 +9,8 @@ class PostgresqlCollationTest < ActiveRecord::PostgreSQLTestCase
   def setup
     @connection = ActiveRecord::Base.connection
     @connection.create_table :postgresql_collations, force: true do |t|
-      t.string :string_c, collation: 'C'
-      t.text :text_posix, collation: 'POSIX'
+      t.string :string_c, collation: "C"
+      t.text :text_posix, collation: "POSIX"
     end
   end
 
@@ -17,37 +19,37 @@ class PostgresqlCollationTest < ActiveRecord::PostgreSQLTestCase
   end
 
   test "string column with collation" do
-    column = @connection.columns(:postgresql_collations).find { |c| c.name == 'string_c' }
+    column = @connection.columns(:postgresql_collations).find { |c| c.name == "string_c" }
     assert_equal :string, column.type
-    assert_equal 'C', column.collation
+    assert_equal "C", column.collation
   end
 
   test "text column with collation" do
-    column = @connection.columns(:postgresql_collations).find { |c| c.name == 'text_posix' }
+    column = @connection.columns(:postgresql_collations).find { |c| c.name == "text_posix" }
     assert_equal :text, column.type
-    assert_equal 'POSIX', column.collation
+    assert_equal "POSIX", column.collation
   end
 
   test "add column with collation" do
-    @connection.add_column :postgresql_collations, :title, :string, collation: 'C'
+    @connection.add_column :postgresql_collations, :title, :string, collation: "C"
 
-    column = @connection.columns(:postgresql_collations).find { |c| c.name == 'title' }
+    column = @connection.columns(:postgresql_collations).find { |c| c.name == "title" }
     assert_equal :string, column.type
-    assert_equal 'C', column.collation
+    assert_equal "C", column.collation
   end
 
   test "change column with collation" do
     @connection.add_column :postgresql_collations, :description, :string
-    @connection.change_column :postgresql_collations, :description, :text, collation: 'POSIX'
+    @connection.change_column :postgresql_collations, :description, :text, collation: "POSIX"
 
-    column = @connection.columns(:postgresql_collations).find { |c| c.name == 'description' }
+    column = @connection.columns(:postgresql_collations).find { |c| c.name == "description" }
     assert_equal :text, column.type
-    assert_equal 'POSIX', column.collation
+    assert_equal "POSIX", column.collation
   end
 
   test "schema dump includes collation" do
     output = dump_table_schema("postgresql_collations")
-    assert_match %r{t.string\s+"string_c",\s+collation: "C"$}, output
-    assert_match %r{t.text\s+"text_posix",\s+collation: "POSIX"$}, output
+    assert_match %r{t\.string\s+"string_c",\s+collation: "C"$}, output
+    assert_match %r{t\.text\s+"text_posix",\s+collation: "POSIX"$}, output
   end
 end
diff --git a/activerecord/test/cases/adapters/postgresql/composite_test.rb b/activerecord/test/cases/adapters/postgresql/composite_test.rb
index 1de87e5f01..5da95f7e2c 100644
--- a/activerecord/test/cases/adapters/postgresql/composite_test.rb
+++ b/activerecord/test/cases/adapters/postgresql/composite_test.rb
@@ -1,5 +1,7 @@
+# frozen_string_literal: true
+
 require "cases/helper"
-require 'support/connection_helper'
+require "support/connection_helper"
 
 module PostgresqlCompositeBehavior
   include ConnectionHelper
@@ -20,7 +22,7 @@ module PostgresqlCompositeBehavior
              street VARCHAR(90)
          );
         SQL
-      @connection.create_table('postgresql_composites') do |t|
+      @connection.create_table("postgresql_composites") do |t|
         t.column :address, :full_address
       end
     end
@@ -29,8 +31,8 @@ module PostgresqlCompositeBehavior
   def teardown
     super
 
-    @connection.drop_table 'postgresql_composites', if_exists: true
-    @connection.execute 'DROP TYPE IF EXISTS full_address'
+    @connection.drop_table "postgresql_composites", if_exists: true
+    @connection.execute "DROP TYPE IF EXISTS full_address"
     reset_connection
     PostgresqlComposite.reset_column_information
   end
@@ -69,12 +71,12 @@ class PostgresqlCompositeTest < ActiveRecord::PostgreSQLTestCase
   end
 
   private
-  def ensure_warning_is_issued
-    warning = capture(:stderr) do
-      PostgresqlComposite.columns_hash
+    def ensure_warning_is_issued
+      warning = capture(:stderr) do
+        PostgresqlComposite.columns_hash
+      end
+      assert_match(/unknown OID \d+: failed to recognize type of 'address'\. It will be treated as String\./, warning)
     end
-    assert_match(/unknown OID \d+: failed to recognize type of 'address'\. It will be treated as String\./, warning)
-  end
 end
 
 class PostgresqlCompositeWithCustomOIDTest < ActiveRecord::PostgreSQLTestCase
@@ -104,7 +106,7 @@ class PostgresqlCompositeWithCustomOIDTest < ActiveRecord::PostgreSQLTestCase
   def setup
     super
 
-    @connection.type_map.register_type "full_address", FullAddressType.new
+    @connection.send(:type_map).register_type "full_address", FullAddressType.new
   end
 
   def test_column
@@ -126,7 +128,7 @@ class PostgresqlCompositeWithCustomOIDTest < ActiveRecord::PostgreSQLTestCase
     composite.address = FullAddress.new("Paris", "Rue Basse")
     composite.save!
 
-    assert_equal 'Paris', composite.reload.address.city
-    assert_equal 'Rue Basse', composite.reload.address.street
+    assert_equal "Paris", composite.reload.address.city
+    assert_equal "Rue Basse", composite.reload.address.street
   end
 end
diff --git a/activerecord/test/cases/adapters/postgresql/connection_test.rb b/activerecord/test/cases/adapters/postgresql/connection_test.rb
index f8403bfe1a..81358b8fc4 100644
--- a/activerecord/test/cases/adapters/postgresql/connection_test.rb
+++ b/activerecord/test/cases/adapters/postgresql/connection_test.rb
@@ -1,5 +1,7 @@
+# frozen_string_literal: true
+
 require "cases/helper"
-require 'support/connection_helper'
+require "support/connection_helper"
 
 module ActiveRecord
   class PostgresqlConnectionTest < ActiveRecord::PostgreSQLTestCase
@@ -13,7 +15,7 @@ module ActiveRecord
     def setup
       super
       @subscriber = SQLSubscriber.new
-      @subscription = ActiveSupport::Notifications.subscribe('sql.active_record', @subscriber)
+      @subscription = ActiveSupport::Notifications.subscribe("sql.active_record", @subscriber)
       @connection = ActiveRecord::Base.connection
     end
 
@@ -23,23 +25,29 @@ module ActiveRecord
     end
 
     def test_truncate
-      count = ActiveRecord::Base.connection.execute("select count(*) from comments").first['count'].to_i
+      count = ActiveRecord::Base.connection.execute("select count(*) from comments").first["count"].to_i
       assert_operator count, :>, 0
       ActiveRecord::Base.connection.truncate("comments")
-      count = ActiveRecord::Base.connection.execute("select count(*) from comments").first['count'].to_i
+      count = ActiveRecord::Base.connection.execute("select count(*) from comments").first["count"].to_i
       assert_equal 0, count
     end
 
     def test_encoding
-      assert_not_nil @connection.encoding
+      assert_queries(1) do
+        assert_not_nil @connection.encoding
+      end
     end
 
     def test_collation
-      assert_not_nil @connection.collation
+      assert_queries(1) do
+        assert_not_nil @connection.collation
+      end
     end
 
     def test_ctype
-      assert_not_nil @connection.ctype
+      assert_queries(1) do
+        assert_not_nil @connection.ctype
+      end
     end
 
     def test_default_client_min_messages
@@ -54,85 +62,85 @@ module ActiveRecord
       NonExistentTable.establish_connection(params)
 
       # Verify the connection param has been applied.
-      expect = NonExistentTable.connection.query('show geqo').first.first
-      assert_equal 'off', expect
+      expect = NonExistentTable.connection.query("show geqo").first.first
+      assert_equal "off", expect
     end
 
     def test_reset
-      @connection.query('ROLLBACK')
-      @connection.query('SET geqo TO off')
+      @connection.query("ROLLBACK")
+      @connection.query("SET geqo TO off")
 
       # Verify the setting has been applied.
-      expect = @connection.query('show geqo').first.first
-      assert_equal 'off', expect
+      expect = @connection.query("show geqo").first.first
+      assert_equal "off", expect
 
       @connection.reset!
 
       # Verify the setting has been cleared.
-      expect = @connection.query('show geqo').first.first
-      assert_equal 'on', expect
+      expect = @connection.query("show geqo").first.first
+      assert_equal "on", expect
     end
 
     def test_reset_with_transaction
-      @connection.query('ROLLBACK')
-      @connection.query('SET geqo TO off')
+      @connection.query("ROLLBACK")
+      @connection.query("SET geqo TO off")
 
       # Verify the setting has been applied.
-      expect = @connection.query('show geqo').first.first
-      assert_equal 'off', expect
+      expect = @connection.query("show geqo").first.first
+      assert_equal "off", expect
 
-      @connection.query('BEGIN')
+      @connection.query("BEGIN")
       @connection.reset!
 
       # Verify the setting has been cleared.
-      expect = @connection.query('show geqo').first.first
-      assert_equal 'on', expect
+      expect = @connection.query("show geqo").first.first
+      assert_equal "on", expect
     end
 
     def test_tables_logs_name
-      ActiveSupport::Deprecation.silence { @connection.tables('hello') }
-      assert_equal 'SCHEMA', @subscriber.logged[0][1]
+      @connection.tables
+      assert_equal "SCHEMA", @subscriber.logged[0][1]
     end
 
     def test_indexes_logs_name
-      @connection.indexes('items', 'hello')
-      assert_equal 'SCHEMA', @subscriber.logged[0][1]
+      @connection.indexes("items")
+      assert_equal "SCHEMA", @subscriber.logged[0][1]
     end
 
     def test_table_exists_logs_name
-      ActiveSupport::Deprecation.silence { @connection.table_exists?('items') }
-      assert_equal 'SCHEMA', @subscriber.logged[0][1]
+      @connection.table_exists?("items")
+      assert_equal "SCHEMA", @subscriber.logged[0][1]
     end
 
     def test_table_alias_length_logs_name
-      @connection.instance_variable_set("@table_alias_length", nil)
+      @connection.instance_variable_set("@max_identifier_length", nil)
       @connection.table_alias_length
-      assert_equal 'SCHEMA', @subscriber.logged[0][1]
+      assert_equal "SCHEMA", @subscriber.logged[0][1]
     end
 
     def test_current_database_logs_name
       @connection.current_database
-      assert_equal 'SCHEMA', @subscriber.logged[0][1]
+      assert_equal "SCHEMA", @subscriber.logged[0][1]
     end
 
     def test_encoding_logs_name
       @connection.encoding
-      assert_equal 'SCHEMA', @subscriber.logged[0][1]
+      assert_equal "SCHEMA", @subscriber.logged[0][1]
     end
 
     def test_schema_names_logs_name
       @connection.schema_names
-      assert_equal 'SCHEMA', @subscriber.logged[0][1]
+      assert_equal "SCHEMA", @subscriber.logged[0][1]
     end
 
     if ActiveRecord::Base.connection.prepared_statements
       def test_statement_key_is_logged
         bind = Relation::QueryAttribute.new(nil, 1, Type::Value.new)
-        @connection.exec_query('SELECT $1::integer', 'SQL', [bind], prepare: true)
+        @connection.exec_query("SELECT $1::integer", "SQL", [bind], prepare: true)
         name = @subscriber.payloads.last[:statement_name]
         assert name
         res = @connection.exec_query("EXPLAIN (FORMAT JSON) EXECUTE #{name}(1)")
-        plan = res.column_types['QUERY PLAN'].deserialize res.rows.first.first
+        plan = res.column_types["QUERY PLAN"].deserialize res.rows.first.first
         assert_operator plan.length, :>, 0
       end
     end
@@ -146,7 +154,7 @@ module ActiveRecord
     # To restart PostgreSQL 9.1 on OS X, installed via MacPorts, ...
     # sudo su postgres -c "pg_ctl restart -D /opt/local/var/db/postgresql91/defaultdb/ -m fast"
     def test_reconnection_after_actual_disconnection_with_verify
-      original_connection_pid = @connection.query('select pg_backend_pid()')
+      original_connection_pid = @connection.query("select pg_backend_pid()")
 
       # Sanity check.
       assert @connection.active?
@@ -155,8 +163,8 @@ module ActiveRecord
         secondary_connection = ActiveRecord::Base.connection_pool.checkout
         secondary_connection.query("select pg_terminate_backend(#{original_connection_pid.first.first})")
         ActiveRecord::Base.connection_pool.checkin(secondary_connection)
-      elsif ARTest.config['with_manual_interventions']
-        puts 'Kill the connection now (e.g. by restarting the PostgreSQL ' +
+      elsif ARTest.config["with_manual_interventions"]
+        puts "Kill the connection now (e.g. by restarting the PostgreSQL " \
           'server with the "-m fast" option) and then press enter.'
         $stdin.gets
       else
@@ -172,19 +180,19 @@ module ActiveRecord
 
       # If we get no exception here, then either we re-connected successfully, or
       # we never actually got disconnected.
-      new_connection_pid = @connection.query('select pg_backend_pid()')
+      new_connection_pid = @connection.query("select pg_backend_pid()")
 
       assert_not_equal original_connection_pid, new_connection_pid,
-        "umm -- looks like you didn't break the connection, because we're still " +
+        "umm -- looks like you didn't break the connection, because we're still " \
         "successfully querying with the same connection pid."
-
+    ensure
       # Repair all fixture connections so other tests won't break.
       @fixture_connections.each(&:verify!)
     end
 
     def test_set_session_variable_true
       run_without_connection do |orig_connection|
-        ActiveRecord::Base.establish_connection(orig_connection.deep_merge({:variables => {:debug_print_plan => true}}))
+        ActiveRecord::Base.establish_connection(orig_connection.deep_merge(variables: { debug_print_plan: true }))
         set_true = ActiveRecord::Base.connection.exec_query "SHOW DEBUG_PRINT_PLAN"
         assert_equal set_true.rows, [["on"]]
       end
@@ -192,7 +200,7 @@ module ActiveRecord
 
     def test_set_session_variable_false
       run_without_connection do |orig_connection|
-        ActiveRecord::Base.establish_connection(orig_connection.deep_merge({:variables => {:debug_print_plan => false}}))
+        ActiveRecord::Base.establish_connection(orig_connection.deep_merge(variables: { debug_print_plan: false }))
         set_false = ActiveRecord::Base.connection.exec_query "SHOW DEBUG_PRINT_PLAN"
         assert_equal set_false.rows, [["off"]]
       end
@@ -201,14 +209,21 @@ module ActiveRecord
     def test_set_session_variable_nil
       run_without_connection do |orig_connection|
         # This should be a no-op that does not raise an error
-        ActiveRecord::Base.establish_connection(orig_connection.deep_merge({:variables => {:debug_print_plan => nil}}))
+        ActiveRecord::Base.establish_connection(orig_connection.deep_merge(variables: { debug_print_plan: nil }))
       end
     end
 
     def test_set_session_variable_default
       run_without_connection do |orig_connection|
         # This should execute a query that does not raise an error
-        ActiveRecord::Base.establish_connection(orig_connection.deep_merge({:variables => {:debug_print_plan => :default}}))
+        ActiveRecord::Base.establish_connection(orig_connection.deep_merge(variables: { debug_print_plan: :default }))
+      end
+    end
+
+    def test_set_session_timezone
+      run_without_connection do |orig_connection|
+        ActiveRecord::Base.establish_connection(orig_connection.deep_merge(variables: { timezone: "America/New_York" }))
+        assert_equal "America/New_York", ActiveRecord::Base.connection.query_value("SHOW TIME ZONE")
       end
     end
 
@@ -224,14 +239,14 @@ module ActiveRecord
       got_lock = @connection.get_advisory_lock(lock_id)
       assert got_lock, "get_advisory_lock should have returned true but it didn't"
 
-      advisory_lock = @connection.query(list_advisory_locks).find {|l| l[1] == lock_id}
+      advisory_lock = @connection.query(list_advisory_locks).find { |l| l[1] == lock_id }
       assert advisory_lock,
         "expected to find an advisory lock with lock_id #{lock_id} but there wasn't one"
 
       released_lock = @connection.release_advisory_lock(lock_id)
       assert released_lock, "expected release_advisory_lock to return true but it didn't"
 
-      advisory_locks = @connection.query(list_advisory_locks).select {|l| l[1] == lock_id}
+      advisory_locks = @connection.query(list_advisory_locks).select { |l| l[1] == lock_id }
       assert_empty advisory_locks,
         "expected to have released advisory lock with lock_id #{lock_id} but it was still held"
     end
@@ -241,17 +256,17 @@ module ActiveRecord
       with_warning_suppression do
         released_non_existent_lock = @connection.release_advisory_lock(fake_lock_id)
         assert_equal released_non_existent_lock, false,
-          'expected release_advisory_lock to return false when there was no lock to release'
+          "expected release_advisory_lock to return false when there was no lock to release"
       end
     end
 
-    protected
+    private
 
-    def with_warning_suppression
-      log_level = @connection.client_min_messages
-      @connection.client_min_messages = 'error'
-      yield
-      @connection.client_min_messages = log_level
-    end
+      def with_warning_suppression
+        log_level = @connection.client_min_messages
+        @connection.client_min_messages = "error"
+        yield
+        @connection.client_min_messages = log_level
+      end
   end
 end
diff --git a/activerecord/test/cases/adapters/postgresql/datatype_test.rb b/activerecord/test/cases/adapters/postgresql/datatype_test.rb
index 232c25cb3b..b7535d5c9a 100644
--- a/activerecord/test/cases/adapters/postgresql/datatype_test.rb
+++ b/activerecord/test/cases/adapters/postgresql/datatype_test.rb
@@ -1,6 +1,7 @@
-require "cases/helper"
-require 'support/ddl_helper'
+# frozen_string_literal: true
 
+require "cases/helper"
+require "support/ddl_helper"
 
 class PostgresqlTime < ActiveRecord::Base
 end
@@ -29,17 +30,17 @@ class PostgresqlDataTypeTest < ActiveRecord::PostgreSQLTestCase
   end
 
   def test_data_type_of_time_types
-    assert_equal :string, @first_time.column_for_attribute(:time_interval).type
-    assert_equal :string, @first_time.column_for_attribute(:scaled_time_interval).type
+    assert_equal :interval, @first_time.column_for_attribute(:time_interval).type
+    assert_equal :interval, @first_time.column_for_attribute(:scaled_time_interval).type
   end
 
   def test_data_type_of_oid_types
-    assert_equal :integer, @first_oid.column_for_attribute(:obj_id).type
+    assert_equal :oid, @first_oid.column_for_attribute(:obj_id).type
   end
 
   def test_time_values
-    assert_equal '-1 years -2 days', @first_time.time_interval
-    assert_equal '-21 days', @first_time.scaled_time_interval
+    assert_equal "-1 years -2 days", @first_time.time_interval
+    assert_equal "-21 days", @first_time.scaled_time_interval
   end
 
   def test_oid_values
@@ -47,10 +48,10 @@ class PostgresqlDataTypeTest < ActiveRecord::PostgreSQLTestCase
   end
 
   def test_update_time
-    @first_time.time_interval = '2 years 3 minutes'
+    @first_time.time_interval = "2 years 3 minutes"
     assert @first_time.save
     assert @first_time.reload
-    assert_equal '2 years 00:03:00', @first_time.time_interval
+    assert_equal "2 years 00:03:00", @first_time.time_interval
   end
 
   def test_update_oid
@@ -62,9 +63,9 @@ class PostgresqlDataTypeTest < ActiveRecord::PostgreSQLTestCase
   end
 
   def test_text_columns_are_limitless_the_upper_limit_is_one_GB
-    assert_equal 'text', @connection.type_to_sql(:text, 100_000)
+    assert_equal "text", @connection.type_to_sql(:text, limit: 100_000)
     assert_raise ActiveRecord::ActiveRecordError do
-      @connection.type_to_sql :text, 4294967295
+      @connection.type_to_sql(:text, limit: 4294967295)
     end
   end
 end
@@ -77,15 +78,15 @@ class PostgresqlInternalDataTypeTest < ActiveRecord::PostgreSQLTestCase
   end
 
   def test_name_column_type
-    with_example_table @connection, 'ex', 'data name' do
-      column = @connection.columns('ex').find { |col| col.name == 'data' }
+    with_example_table @connection, "ex", "data name" do
+      column = @connection.columns("ex").find { |col| col.name == "data" }
       assert_equal :string, column.type
     end
   end
 
   def test_char_column_type
-    with_example_table @connection, 'ex', 'data "char"' do
-      column = @connection.columns('ex').find { |col| col.name == 'data' }
+    with_example_table @connection, "ex", 'data "char"' do
+      column = @connection.columns("ex").find { |col| col.name == "data" }
       assert_equal :string, column.type
     end
   end
diff --git a/activerecord/test/cases/adapters/postgresql/domain_test.rb b/activerecord/test/cases/adapters/postgresql/domain_test.rb
index 6102ddacd1..dafbc0a3db 100644
--- a/activerecord/test/cases/adapters/postgresql/domain_test.rb
+++ b/activerecord/test/cases/adapters/postgresql/domain_test.rb
@@ -1,5 +1,7 @@
+# frozen_string_literal: true
+
 require "cases/helper"
-require 'support/connection_helper'
+require "support/connection_helper"
 
 class PostgresqlDomainTest < ActiveRecord::PostgreSQLTestCase
   include ConnectionHelper
@@ -12,15 +14,15 @@ class PostgresqlDomainTest < ActiveRecord::PostgreSQLTestCase
     @connection = ActiveRecord::Base.connection
     @connection.transaction do
       @connection.execute "CREATE DOMAIN custom_money as numeric(8,2)"
-      @connection.create_table('postgresql_domains') do |t|
+      @connection.create_table("postgresql_domains") do |t|
         t.column :price, :custom_money
       end
     end
   end
 
   teardown do
-    @connection.drop_table 'postgresql_domains', if_exists: true
-    @connection.execute 'DROP DOMAIN IF EXISTS custom_money'
+    @connection.drop_table "postgresql_domains", if_exists: true
+    @connection.execute "DROP DOMAIN IF EXISTS custom_money"
     reset_connection
   end
 
@@ -42,6 +44,6 @@ class PostgresqlDomainTest < ActiveRecord::PostgreSQLTestCase
     record.price = "34.15"
     record.save!
 
-    assert_equal BigDecimal.new("34.15"), record.reload.price
+    assert_equal BigDecimal("34.15"), record.reload.price
   end
 end
diff --git a/activerecord/test/cases/adapters/postgresql/enum_test.rb b/activerecord/test/cases/adapters/postgresql/enum_test.rb
index 6816a6514b..3d3cbe11a3 100644
--- a/activerecord/test/cases/adapters/postgresql/enum_test.rb
+++ b/activerecord/test/cases/adapters/postgresql/enum_test.rb
@@ -1,5 +1,7 @@
+# frozen_string_literal: true
+
 require "cases/helper"
-require 'support/connection_helper'
+require "support/connection_helper"
 
 class PostgresqlEnumTest < ActiveRecord::PostgreSQLTestCase
   include ConnectionHelper
@@ -14,15 +16,15 @@ class PostgresqlEnumTest < ActiveRecord::PostgreSQLTestCase
       @connection.execute <<-SQL
         CREATE TYPE mood AS ENUM ('sad', 'ok', 'happy');
       SQL
-      @connection.create_table('postgresql_enums') do |t|
+      @connection.create_table("postgresql_enums") do |t|
         t.column :current_mood, :mood
       end
     end
   end
 
   teardown do
-    @connection.drop_table 'postgresql_enums', if_exists: true
-    @connection.execute 'DROP TYPE IF EXISTS mood'
+    @connection.drop_table "postgresql_enums", if_exists: true
+    @connection.execute "DROP TYPE IF EXISTS mood"
     reset_connection
   end
 
@@ -37,10 +39,10 @@ class PostgresqlEnumTest < ActiveRecord::PostgreSQLTestCase
   end
 
   def test_enum_defaults
-    @connection.add_column 'postgresql_enums', 'good_mood', :mood, default: 'happy'
+    @connection.add_column "postgresql_enums", "good_mood", :mood, default: "happy"
     PostgresqlEnum.reset_column_information
 
-    assert_equal "happy", PostgresqlEnum.column_defaults['good_mood']
+    assert_equal "happy", PostgresqlEnum.column_defaults["good_mood"]
     assert_equal "happy", PostgresqlEnum.new.good_mood
   ensure
     PostgresqlEnum.reset_column_information
diff --git a/activerecord/test/cases/adapters/postgresql/explain_test.rb b/activerecord/test/cases/adapters/postgresql/explain_test.rb
index 29bf2c15ea..be525383e9 100644
--- a/activerecord/test/cases/adapters/postgresql/explain_test.rb
+++ b/activerecord/test/cases/adapters/postgresql/explain_test.rb
@@ -1,20 +1,22 @@
+# frozen_string_literal: true
+
 require "cases/helper"
-require 'models/developer'
-require 'models/computer'
+require "models/author"
+require "models/post"
 
 class PostgreSQLExplainTest < ActiveRecord::PostgreSQLTestCase
-  fixtures :developers
+  fixtures :authors
 
   def test_explain_for_one_query
-    explain = Developer.where(id: 1).explain
-    assert_match %r(EXPLAIN for: SELECT "developers".* FROM "developers" WHERE "developers"."id" = \$?1), explain
+    explain = Author.where(id: 1).explain
+    assert_match %r(EXPLAIN for: SELECT "authors"\.\* FROM "authors" WHERE "authors"\."id" = (?:\$1 \[\["id", 1\]\]|1)), explain
     assert_match %(QUERY PLAN), explain
   end
 
   def test_explain_with_eager_loading
-    explain = Developer.where(id: 1).includes(:audit_logs).explain
+    explain = Author.where(id: 1).includes(:posts).explain
     assert_match %(QUERY PLAN), explain
-    assert_match %r(EXPLAIN for: SELECT "developers".* FROM "developers" WHERE "developers"."id" = \$?1), explain
-    assert_match %(EXPLAIN for: SELECT "audit_logs".* FROM "audit_logs" WHERE "audit_logs"."developer_id" = 1), explain
+    assert_match %r(EXPLAIN for: SELECT "authors"\.\* FROM "authors" WHERE "authors"\."id" = (?:\$1 \[\["id", 1\]\]|1)), explain
+    assert_match %r(EXPLAIN for: SELECT "posts"\.\* FROM "posts" WHERE "posts"\."author_id" = (?:\$1 \[\["author_id", 1\]\]|1)), explain
   end
 end
diff --git a/activerecord/test/cases/adapters/postgresql/extension_migration_test.rb b/activerecord/test/cases/adapters/postgresql/extension_migration_test.rb
index b56c226763..df97ab11e7 100644
--- a/activerecord/test/cases/adapters/postgresql/extension_migration_test.rb
+++ b/activerecord/test/cases/adapters/postgresql/extension_migration_test.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require "cases/helper"
 
 class PostgresqlExtensionMigrationTest < ActiveRecord::PostgreSQLTestCase
@@ -20,10 +22,6 @@ class PostgresqlExtensionMigrationTest < ActiveRecord::PostgreSQLTestCase
 
     @connection = ActiveRecord::Base.connection
 
-    unless @connection.supports_extensions?
-      return skip("no extension support")
-    end
-
     @old_schema_migration_table_name = ActiveRecord::SchemaMigration.table_name
     @old_table_name_prefix = ActiveRecord::Base.table_name_prefix
     @old_table_name_suffix = ActiveRecord::Base.table_name_suffix
diff --git a/activerecord/test/cases/adapters/postgresql/full_text_test.rb b/activerecord/test/cases/adapters/postgresql/full_text_test.rb
index bde7513339..c6f1e1727f 100644
--- a/activerecord/test/cases/adapters/postgresql/full_text_test.rb
+++ b/activerecord/test/cases/adapters/postgresql/full_text_test.rb
@@ -1,5 +1,7 @@
+# frozen_string_literal: true
+
 require "cases/helper"
-require 'support/schema_dumping_helper'
+require "support/schema_dumping_helper"
 
 class PostgresqlFullTextTest < ActiveRecord::PostgreSQLTestCase
   include SchemaDumpingHelper
@@ -7,13 +9,13 @@ class PostgresqlFullTextTest < ActiveRecord::PostgreSQLTestCase
 
   setup do
     @connection = ActiveRecord::Base.connection
-    @connection.create_table('tsvectors') do |t|
-      t.tsvector 'text_vector'
+    @connection.create_table("tsvectors") do |t|
+      t.tsvector "text_vector"
     end
   end
 
   teardown do
-    @connection.drop_table 'tsvectors', if_exists: true
+    @connection.drop_table "tsvectors", if_exists: true
   end
 
   def test_tsvector_column
diff --git a/activerecord/test/cases/adapters/postgresql/geometric_test.rb b/activerecord/test/cases/adapters/postgresql/geometric_test.rb
index 66f0a70394..e1ba00e07b 100644
--- a/activerecord/test/cases/adapters/postgresql/geometric_test.rb
+++ b/activerecord/test/cases/adapters/postgresql/geometric_test.rb
@@ -1,6 +1,8 @@
+# frozen_string_literal: true
+
 require "cases/helper"
-require 'support/connection_helper'
-require 'support/schema_dumping_helper'
+require "support/connection_helper"
+require "support/schema_dumping_helper"
 
 class PostgresqlPointTest < ActiveRecord::PostgreSQLTestCase
   include ConnectionHelper
@@ -18,7 +20,7 @@ class PostgresqlPointTest < ActiveRecord::PostgreSQLTestCase
 
   def setup
     @connection = ActiveRecord::Base.connection
-    @connection.create_table('postgresql_points') do |t|
+    @connection.create_table("postgresql_points") do |t|
       t.point :x
       t.point :y, default: [12.2, 13.3]
       t.point :z, default: "(14.4,15.5)"
@@ -27,22 +29,10 @@ class PostgresqlPointTest < ActiveRecord::PostgreSQLTestCase
       t.point :legacy_y, default: [12.2, 13.3]
       t.point :legacy_z, default: "(14.4,15.5)"
     end
-    @connection.create_table('deprecated_points') do |t|
-      t.point :x
-    end
   end
 
   teardown do
-    @connection.drop_table 'postgresql_points', if_exists: true
-    @connection.drop_table 'deprecated_points', if_exists: true
-  end
-
-  class DeprecatedPoint < ActiveRecord::Base; end
-
-  def test_deprecated_legacy_type
-    assert_deprecated do
-      DeprecatedPoint.new
-    end
+    @connection.drop_table "postgresql_points", if_exists: true
   end
 
   def test_column
@@ -56,10 +46,10 @@ class PostgresqlPointTest < ActiveRecord::PostgreSQLTestCase
   end
 
   def test_default
-    assert_equal ActiveRecord::Point.new(12.2, 13.3), PostgresqlPoint.column_defaults['y']
+    assert_equal ActiveRecord::Point.new(12.2, 13.3), PostgresqlPoint.column_defaults["y"]
     assert_equal ActiveRecord::Point.new(12.2, 13.3), PostgresqlPoint.new.y
 
-    assert_equal ActiveRecord::Point.new(14.4, 15.5), PostgresqlPoint.column_defaults['z']
+    assert_equal ActiveRecord::Point.new(14.4, 15.5), PostgresqlPoint.column_defaults["z"]
     assert_equal ActiveRecord::Point.new(14.4, 15.5), PostgresqlPoint.new.z
   end
 
@@ -105,10 +95,8 @@ class PostgresqlPointTest < ActiveRecord::PostgreSQLTestCase
   end
 
   def test_empty_string_assignment
-    assert_nothing_raised { PostgresqlPoint.new(x: "") }
-
     p = PostgresqlPoint.new(x: "")
-    assert_equal nil, p.x
+    assert_nil p.x
   end
 
   def test_array_of_points_round_trip
@@ -136,10 +124,10 @@ class PostgresqlPointTest < ActiveRecord::PostgreSQLTestCase
   end
 
   def test_legacy_default
-    assert_equal [12.2, 13.3], PostgresqlPoint.column_defaults['legacy_y']
+    assert_equal [12.2, 13.3], PostgresqlPoint.column_defaults["legacy_y"]
     assert_equal [12.2, 13.3], PostgresqlPoint.new.legacy_y
 
-    assert_equal [14.4, 15.5], PostgresqlPoint.column_defaults['legacy_z']
+    assert_equal [14.4, 15.5], PostgresqlPoint.column_defaults["legacy_z"]
     assert_equal [14.4, 15.5], PostgresqlPoint.new.legacy_z
   end
 
@@ -190,51 +178,51 @@ class PostgresqlGeometricTest < ActiveRecord::PostgreSQLTestCase
   end
 
   teardown do
-    @connection.drop_table 'postgresql_geometrics', if_exists: true
+    @connection.drop_table "postgresql_geometrics", if_exists: true
   end
 
   def test_geometric_types
     g = PostgresqlGeometric.new(
-      :a_line_segment => '(2.0, 3), (5.5, 7.0)',
-      :a_box          => '2.0, 3, 5.5, 7.0',
-      :a_path         => '[(2.0, 3), (5.5, 7.0), (8.5, 11.0)]',
-      :a_polygon      => '((2.0, 3), (5.5, 7.0), (8.5, 11.0))',
-      :a_circle       => '<(5.3, 10.4), 2>'
+      a_line_segment: "(2.0, 3), (5.5, 7.0)",
+      a_box: "2.0, 3, 5.5, 7.0",
+      a_path: "[(2.0, 3), (5.5, 7.0), (8.5, 11.0)]",
+      a_polygon: "((2.0, 3), (5.5, 7.0), (8.5, 11.0))",
+      a_circle: "<(5.3, 10.4), 2>"
     )
 
     g.save!
 
     h = PostgresqlGeometric.find(g.id)
 
-    assert_equal '[(2,3),(5.5,7)]', h.a_line_segment
-    assert_equal '(5.5,7),(2,3)', h.a_box # reordered to store upper right corner then bottom left corner
-    assert_equal '[(2,3),(5.5,7),(8.5,11)]', h.a_path
-    assert_equal '((2,3),(5.5,7),(8.5,11))', h.a_polygon
-    assert_equal '<(5.3,10.4),2>', h.a_circle
+    assert_equal "[(2,3),(5.5,7)]", h.a_line_segment
+    assert_equal "(5.5,7),(2,3)", h.a_box # reordered to store upper right corner then bottom left corner
+    assert_equal "[(2,3),(5.5,7),(8.5,11)]", h.a_path
+    assert_equal "((2,3),(5.5,7),(8.5,11))", h.a_polygon
+    assert_equal "<(5.3,10.4),2>", h.a_circle
   end
 
   def test_alternative_format
     g = PostgresqlGeometric.new(
-      :a_line_segment => '((2.0, 3), (5.5, 7.0))',
-      :a_box          => '(2.0, 3), (5.5, 7.0)',
-      :a_path         => '((2.0, 3), (5.5, 7.0), (8.5, 11.0))',
-      :a_polygon      => '2.0, 3, 5.5, 7.0, 8.5, 11.0',
-      :a_circle       => '((5.3, 10.4), 2)'
+      a_line_segment: "((2.0, 3), (5.5, 7.0))",
+      a_box: "(2.0, 3), (5.5, 7.0)",
+      a_path: "((2.0, 3), (5.5, 7.0), (8.5, 11.0))",
+      a_polygon: "2.0, 3, 5.5, 7.0, 8.5, 11.0",
+      a_circle: "((5.3, 10.4), 2)"
     )
 
     g.save!
 
     h = PostgresqlGeometric.find(g.id)
-    assert_equal '[(2,3),(5.5,7)]', h.a_line_segment
-    assert_equal '(5.5,7),(2,3)', h.a_box   # reordered to store upper right corner then bottom left corner
-    assert_equal '((2,3),(5.5,7),(8.5,11))', h.a_path
-    assert_equal '((2,3),(5.5,7),(8.5,11))', h.a_polygon
-    assert_equal '<(5.3,10.4),2>', h.a_circle
+    assert_equal "[(2,3),(5.5,7)]", h.a_line_segment
+    assert_equal "(5.5,7),(2,3)", h.a_box   # reordered to store upper right corner then bottom left corner
+    assert_equal "((2,3),(5.5,7),(8.5,11))", h.a_path
+    assert_equal "((2,3),(5.5,7),(8.5,11))", h.a_polygon
+    assert_equal "<(5.3,10.4),2>", h.a_circle
   end
 
   def test_geometric_function
-    PostgresqlGeometric.create! a_path: '[(2.0, 3), (5.5, 7.0), (8.5, 11.0)]'  # [ ] is an open path
-    PostgresqlGeometric.create! a_path: '((2.0, 3), (5.5, 7.0), (8.5, 11.0))'  # ( ) is a closed path
+    PostgresqlGeometric.create! a_path: "[(2.0, 3), (5.5, 7.0), (8.5, 11.0)]"  # [ ] is an open path
+    PostgresqlGeometric.create! a_path: "((2.0, 3), (5.5, 7.0), (8.5, 11.0))"  # ( ) is a closed path
 
     objs = PostgresqlGeometric.find_by_sql "SELECT isopen(a_path) FROM postgresql_geometrics ORDER BY id ASC"
     assert_equal [true, false], objs.map(&:isopen)
@@ -270,28 +258,28 @@ class PostgreSQLGeometricLineTest < ActiveRecord::PostgreSQLTestCase
 
   teardown do
     if defined?(@connection)
-      @connection.drop_table 'postgresql_lines', if_exists: true
+      @connection.drop_table "postgresql_lines", if_exists: true
     end
   end
 
   def test_geometric_line_type
     g = PostgresqlLine.new(
-      a_line: '{2.0, 3, 5.5}'
+      a_line: "{2.0, 3, 5.5}"
     )
     g.save!
 
     h = PostgresqlLine.find(g.id)
-    assert_equal '{2,3,5.5}', h.a_line
+    assert_equal "{2,3,5.5}", h.a_line
   end
 
   def test_alternative_format_line_type
     g = PostgresqlLine.new(
-      a_line: '(2.0, 3), (4.0, 6.0)'
+      a_line: "(2.0, 3), (4.0, 6.0)"
     )
     g.save!
 
     h = PostgresqlLine.find(g.id)
-    assert_equal '{1.5,-1,0}', h.a_line
+    assert_equal "{1.5,-1,0}", h.a_line
   end
 
   def test_schema_dumping_for_line_type
@@ -374,12 +362,12 @@ class PostgreSQLGeometricTypesTest < ActiveRecord::PostgreSQLTestCase
 
   private
 
-  def assert_column_exists(column_name)
-    assert connection.column_exists?(table_name, column_name)
-  end
+    def assert_column_exists(column_name)
+      assert connection.column_exists?(table_name, column_name)
+    end
 
-  def assert_type_correct(column_name, type)
-    column = connection.columns(table_name).find { |c| c.name == column_name.to_s }
-    assert_equal type, column.type
-  end
+    def assert_type_correct(column_name, type)
+      column = connection.columns(table_name).find { |c| c.name == column_name.to_s }
+      assert_equal type, column.type
+    end
 end
diff --git a/activerecord/test/cases/adapters/postgresql/hstore_test.rb b/activerecord/test/cases/adapters/postgresql/hstore_test.rb
index 27cc65a643..f09e34b5f2 100644
--- a/activerecord/test/cases/adapters/postgresql/hstore_test.rb
+++ b/activerecord/test/cases/adapters/postgresql/hstore_test.rb
@@ -1,327 +1,353 @@
+# frozen_string_literal: true
+
 require "cases/helper"
-require 'support/schema_dumping_helper'
+require "support/schema_dumping_helper"
 
-if ActiveRecord::Base.connection.supports_extensions?
-  class PostgresqlHstoreTest < ActiveRecord::PostgreSQLTestCase
-    include SchemaDumpingHelper
-    class Hstore < ActiveRecord::Base
-      self.table_name = 'hstores'
+class PostgresqlHstoreTest < ActiveRecord::PostgreSQLTestCase
+  include SchemaDumpingHelper
+  class Hstore < ActiveRecord::Base
+    self.table_name = "hstores"
 
-      store_accessor :settings, :language, :timezone
-    end
+    store_accessor :settings, :language, :timezone
+  end
 
-    def setup
-      @connection = ActiveRecord::Base.connection
+  class FakeParameters
+    def to_unsafe_h
+      { "hi" => "hi" }
+    end
+  end
 
-      unless @connection.extension_enabled?('hstore')
-        @connection.enable_extension 'hstore'
-        @connection.commit_db_transaction
-      end
+  def setup
+    @connection = ActiveRecord::Base.connection
 
-      @connection.reconnect!
+    enable_extension!("hstore", @connection)
 
-      @connection.transaction do
-        @connection.create_table('hstores') do |t|
-          t.hstore 'tags', :default => ''
-          t.hstore 'payload', array: true
-          t.hstore 'settings'
-        end
+    @connection.transaction do
+      @connection.create_table("hstores") do |t|
+        t.hstore "tags", default: ""
+        t.hstore "payload", array: true
+        t.hstore "settings"
       end
-      Hstore.reset_column_information
-      @column = Hstore.columns_hash['tags']
-      @type = Hstore.type_for_attribute("tags")
-    end
-
-    teardown do
-      @connection.drop_table 'hstores', if_exists: true
     end
+    Hstore.reset_column_information
+    @column = Hstore.columns_hash["tags"]
+    @type = Hstore.type_for_attribute("tags")
+  end
 
-    def test_hstore_included_in_extensions
-      assert @connection.respond_to?(:extensions), "connection should have a list of extensions"
-      assert @connection.extensions.include?('hstore'), "extension list should include hstore"
-    end
+  teardown do
+    @connection.drop_table "hstores", if_exists: true
+    disable_extension!("hstore", @connection)
+  end
 
-    def test_disable_enable_hstore
-      assert @connection.extension_enabled?('hstore')
-      @connection.disable_extension 'hstore'
-      assert_not @connection.extension_enabled?('hstore')
-      @connection.enable_extension 'hstore'
-      assert @connection.extension_enabled?('hstore')
-    ensure
-      # Restore column(s) dropped by `drop extension hstore cascade;`
-      load_schema
-    end
+  def test_hstore_included_in_extensions
+    assert @connection.respond_to?(:extensions), "connection should have a list of extensions"
+    assert_includes @connection.extensions, "hstore", "extension list should include hstore"
+  end
 
-    def test_column
-      assert_equal :hstore, @column.type
-      assert_equal "hstore", @column.sql_type
-      assert_not @column.array?
+  def test_disable_enable_hstore
+    assert @connection.extension_enabled?("hstore")
+    @connection.disable_extension "hstore"
+    assert_not @connection.extension_enabled?("hstore")
+    @connection.enable_extension "hstore"
+    assert @connection.extension_enabled?("hstore")
+  ensure
+    # Restore column(s) dropped by `drop extension hstore cascade;`
+    load_schema
+  end
 
-      assert_not @type.binary?
-    end
+  def test_column
+    assert_equal :hstore, @column.type
+    assert_equal "hstore", @column.sql_type
+    assert_not @column.array?
 
-    def test_default
-      @connection.add_column 'hstores', 'permissions', :hstore, default: '"users"=>"read", "articles"=>"write"'
-      Hstore.reset_column_information
+    assert_not @type.binary?
+  end
 
-      assert_equal({"users"=>"read", "articles"=>"write"}, Hstore.column_defaults['permissions'])
-      assert_equal({"users"=>"read", "articles"=>"write"}, Hstore.new.permissions)
-    ensure
-      Hstore.reset_column_information
-    end
+  def test_default
+    @connection.add_column "hstores", "permissions", :hstore, default: '"users"=>"read", "articles"=>"write"'
+    Hstore.reset_column_information
 
-    def test_change_table_supports_hstore
-      @connection.transaction do
-        @connection.change_table('hstores') do |t|
-          t.hstore 'users', default: ''
-        end
-        Hstore.reset_column_information
-        column = Hstore.columns_hash['users']
-        assert_equal :hstore, column.type
+    assert_equal({ "users" => "read", "articles" => "write" }, Hstore.column_defaults["permissions"])
+    assert_equal({ "users" => "read", "articles" => "write" }, Hstore.new.permissions)
+  ensure
+    Hstore.reset_column_information
+  end
 
-        raise ActiveRecord::Rollback # reset the schema change
+  def test_change_table_supports_hstore
+    @connection.transaction do
+      @connection.change_table("hstores") do |t|
+        t.hstore "users", default: ""
       end
-    ensure
       Hstore.reset_column_information
+      column = Hstore.columns_hash["users"]
+      assert_equal :hstore, column.type
+
+      raise ActiveRecord::Rollback # reset the schema change
     end
+  ensure
+    Hstore.reset_column_information
+  end
 
-    def test_hstore_migration
-      hstore_migration = Class.new(ActiveRecord::Migration::Current) do
-        def change
-          change_table("hstores") do |t|
-            t.hstore :keys
-          end
+  def test_hstore_migration
+    hstore_migration = Class.new(ActiveRecord::Migration::Current) do
+      def change
+        change_table("hstores") do |t|
+          t.hstore :keys
         end
       end
-
-      hstore_migration.new.suppress_messages do
-        hstore_migration.migrate(:up)
-        assert_includes @connection.columns(:hstores).map(&:name), "keys"
-        hstore_migration.migrate(:down)
-        assert_not_includes @connection.columns(:hstores).map(&:name), "keys"
-      end
     end
 
-    def test_cast_value_on_write
-      x = Hstore.new tags: {"bool" => true, "number" => 5}
-      assert_equal({"bool" => true, "number" => 5}, x.tags_before_type_cast)
-      assert_equal({"bool" => "true", "number" => "5"}, x.tags)
-      x.save
-      assert_equal({"bool" => "true", "number" => "5"}, x.reload.tags)
+    hstore_migration.new.suppress_messages do
+      hstore_migration.migrate(:up)
+      assert_includes @connection.columns(:hstores).map(&:name), "keys"
+      hstore_migration.migrate(:down)
+      assert_not_includes @connection.columns(:hstores).map(&:name), "keys"
     end
+  end
 
-    def test_type_cast_hstore
-      assert_equal({'1' => '2'}, @type.deserialize("\"1\"=>\"2\""))
-      assert_equal({}, @type.deserialize(""))
-      assert_equal({'key'=>nil}, @type.deserialize('key => NULL'))
-      assert_equal({'c'=>'}','"a"'=>'b "a b'}, @type.deserialize(%q(c=>"}", "\"a\""=>"b \"a b")))
-    end
+  def test_cast_value_on_write
+    x = Hstore.new tags: { "bool" => true, "number" => 5 }
+    assert_equal({ "bool" => true, "number" => 5 }, x.tags_before_type_cast)
+    assert_equal({ "bool" => "true", "number" => "5" }, x.tags)
+    x.save
+    assert_equal({ "bool" => "true", "number" => "5" }, x.reload.tags)
+  end
 
-    def test_with_store_accessors
-      x = Hstore.new(language: "fr", timezone: "GMT")
-      assert_equal "fr", x.language
-      assert_equal "GMT", x.timezone
+  def test_type_cast_hstore
+    assert_equal({ "1" => "2" }, @type.deserialize("\"1\"=>\"2\""))
+    assert_equal({}, @type.deserialize(""))
+    assert_equal({ "key" => nil }, @type.deserialize("key => NULL"))
+    assert_equal({ "c" => "}", '"a"' => 'b "a b' }, @type.deserialize(%q(c=>"}", "\"a\""=>"b \"a b")))
+  end
 
-      x.save!
-      x = Hstore.first
-      assert_equal "fr", x.language
-      assert_equal "GMT", x.timezone
+  def test_with_store_accessors
+    x = Hstore.new(language: "fr", timezone: "GMT")
+    assert_equal "fr", x.language
+    assert_equal "GMT", x.timezone
 
-      x.language = "de"
-      x.save!
+    x.save!
+    x = Hstore.first
+    assert_equal "fr", x.language
+    assert_equal "GMT", x.timezone
 
-      x = Hstore.first
-      assert_equal "de", x.language
-      assert_equal "GMT", x.timezone
-    end
+    x.language = "de"
+    x.save!
 
-    def test_duplication_with_store_accessors
-      x = Hstore.new(language: "fr", timezone: "GMT")
-      assert_equal "fr", x.language
-      assert_equal "GMT", x.timezone
+    x = Hstore.first
+    assert_equal "de", x.language
+    assert_equal "GMT", x.timezone
+  end
 
-      y = x.dup
-      assert_equal "fr", y.language
-      assert_equal "GMT", y.timezone
-    end
+  def test_duplication_with_store_accessors
+    x = Hstore.new(language: "fr", timezone: "GMT")
+    assert_equal "fr", x.language
+    assert_equal "GMT", x.timezone
 
-    def test_yaml_round_trip_with_store_accessors
-      x = Hstore.new(language: "fr", timezone: "GMT")
-      assert_equal "fr", x.language
-      assert_equal "GMT", x.timezone
+    y = x.dup
+    assert_equal "fr", y.language
+    assert_equal "GMT", y.timezone
+  end
 
-      y = YAML.load(YAML.dump(x))
-      assert_equal "fr", y.language
-      assert_equal "GMT", y.timezone
-    end
+  def test_yaml_round_trip_with_store_accessors
+    x = Hstore.new(language: "fr", timezone: "GMT")
+    assert_equal "fr", x.language
+    assert_equal "GMT", x.timezone
 
-    def test_changes_in_place
-      hstore = Hstore.create!(settings: { 'one' => 'two' })
-      hstore.settings['three'] = 'four'
-      hstore.save!
-      hstore.reload
+    y = YAML.load(YAML.dump(x))
+    assert_equal "fr", y.language
+    assert_equal "GMT", y.timezone
+  end
 
-      assert_equal 'four', hstore.settings['three']
-      assert_not hstore.changed?
-    end
+  def test_changes_in_place
+    hstore = Hstore.create!(settings: { "one" => "two" })
+    hstore.settings["three"] = "four"
+    hstore.save!
+    hstore.reload
 
-    def test_gen1
-      assert_equal(%q(" "=>""), @type.serialize({' '=>''}))
-    end
+    assert_equal "four", hstore.settings["three"]
+    assert_not hstore.changed?
+  end
 
-    def test_gen2
-      assert_equal(%q(","=>""), @type.serialize({','=>''}))
-    end
+  def test_dirty_from_user_equal
+    settings = { "alongkey" => "anything", "key" => "value" }
+    hstore = Hstore.create!(settings: settings)
 
-    def test_gen3
-      assert_equal(%q("="=>""), @type.serialize({'='=>''}))
-    end
+    hstore.settings = { "key" => "value", "alongkey" => "anything" }
+    assert_equal settings, hstore.settings
+    refute hstore.changed?
+  end
 
-    def test_gen4
-      assert_equal(%q(">"=>""), @type.serialize({'>'=>''}))
-    end
+  def test_hstore_dirty_from_database_equal
+    settings = { "alongkey" => "anything", "key" => "value" }
+    hstore = Hstore.create!(settings: settings)
+    hstore.reload
 
-    def test_parse1
-      assert_equal({'a'=>nil,'b'=>nil,'c'=>'NuLl','null'=>'c'}, @type.deserialize('a=>null,b=>NuLl,c=>"NuLl",null=>c'))
-    end
+    assert_equal settings, hstore.settings
+    hstore.settings = settings
+    refute hstore.changed?
+  end
 
-    def test_parse2
-      assert_equal({" " => " "},  @type.deserialize("\\ =>\\ "))
-    end
+  def test_gen1
+    assert_equal('" "=>""', @type.serialize(" " => ""))
+  end
 
-    def test_parse3
-      assert_equal({"=" => ">"},  @type.deserialize("==>>"))
-    end
+  def test_gen2
+    assert_equal('","=>""', @type.serialize("," => ""))
+  end
 
-    def test_parse4
-      assert_equal({"=a"=>"q=w"},   @type.deserialize('\=a=>q=w'))
-    end
+  def test_gen3
+    assert_equal('"="=>""', @type.serialize("=" => ""))
+  end
 
-    def test_parse5
-      assert_equal({"=a"=>"q=w"},   @type.deserialize('"=a"=>q\=w'))
-    end
+  def test_gen4
+    assert_equal('">"=>""', @type.serialize(">" => ""))
+  end
 
-    def test_parse6
-      assert_equal({"\"a"=>"q>w"},  @type.deserialize('"\"a"=>q>w'))
-    end
+  def test_parse1
+    assert_equal({ "a" => nil, "b" => nil, "c" => "NuLl", "null" => "c" }, @type.deserialize('a=>null,b=>NuLl,c=>"NuLl",null=>c'))
+  end
 
-    def test_parse7
-      assert_equal({"\"a"=>"q\"w"}, @type.deserialize('\"a=>q"w'))
-    end
+  def test_parse2
+    assert_equal({ " " => " " },  @type.deserialize("\\ =>\\ "))
+  end
 
-    def test_rewrite
-      @connection.execute "insert into hstores (tags) VALUES ('1=>2')"
-      x = Hstore.first
-      x.tags = { '"a\'' => 'b' }
-      assert x.save!
-    end
+  def test_parse3
+    assert_equal({ "=" => ">" },  @type.deserialize("==>>"))
+  end
 
-    def test_select
-      @connection.execute "insert into hstores (tags) VALUES ('1=>2')"
-      x = Hstore.first
-      assert_equal({'1' => '2'}, x.tags)
-    end
+  def test_parse4
+    assert_equal({ "=a" => "q=w" },   @type.deserialize('\=a=>q=w'))
+  end
 
-    def test_array_cycle
-      assert_array_cycle([{"AA" => "BB", "CC" => "DD"}, {"AA" => nil}])
-    end
+  def test_parse5
+    assert_equal({ "=a" => "q=w" },   @type.deserialize('"=a"=>q\=w'))
+  end
 
-    def test_array_strings_with_quotes
-      assert_array_cycle([{'this has' => 'some "s that need to be escaped"'}])
-    end
+  def test_parse6
+    assert_equal({ "\"a" => "q>w" },  @type.deserialize('"\"a"=>q>w'))
+  end
 
-    def test_array_strings_with_commas
-      assert_array_cycle([{'this,has' => 'many,values'}])
-    end
+  def test_parse7
+    assert_equal({ "\"a" => "q\"w" }, @type.deserialize('\"a=>q"w'))
+  end
 
-    def test_array_strings_with_array_delimiters
-      assert_array_cycle(['{' => '}'])
-    end
+  def test_rewrite
+    @connection.execute "insert into hstores (tags) VALUES ('1=>2')"
+    x = Hstore.first
+    x.tags = { '"a\'' => "b" }
+    assert x.save!
+  end
 
-    def test_array_strings_with_null_strings
-      assert_array_cycle([{'NULL' => 'NULL'}])
-    end
+  def test_select
+    @connection.execute "insert into hstores (tags) VALUES ('1=>2')"
+    x = Hstore.first
+    assert_equal({ "1" => "2" }, x.tags)
+  end
 
-    def test_contains_nils
-      assert_array_cycle([{'NULL' => nil}])
-    end
+  def test_array_cycle
+    assert_array_cycle([{ "AA" => "BB", "CC" => "DD" }, { "AA" => nil }])
+  end
 
-    def test_select_multikey
-      @connection.execute "insert into hstores (tags) VALUES ('1=>2,2=>3')"
-      x = Hstore.first
-      assert_equal({'1' => '2', '2' => '3'}, x.tags)
-    end
+  def test_array_strings_with_quotes
+    assert_array_cycle([{ "this has" => 'some "s that need to be escaped"' }])
+  end
 
-    def test_create
-      assert_cycle('a' => 'b', '1' => '2')
-    end
+  def test_array_strings_with_commas
+    assert_array_cycle([{ "this,has" => "many,values" }])
+  end
 
-    def test_nil
-      assert_cycle('a' => nil)
-    end
+  def test_array_strings_with_array_delimiters
+    assert_array_cycle(["{" => "}"])
+  end
 
-    def test_quotes
-      assert_cycle('a' => 'b"ar', '1"foo' => '2')
-    end
+  def test_array_strings_with_null_strings
+    assert_array_cycle([{ "NULL" => "NULL" }])
+  end
 
-    def test_whitespace
-      assert_cycle('a b' => 'b ar', '1"foo' => '2')
-    end
+  def test_contains_nils
+    assert_array_cycle([{ "NULL" => nil }])
+  end
 
-    def test_backslash
-      assert_cycle('a\\b' => 'b\\ar', '1"foo' => '2')
-    end
+  def test_select_multikey
+    @connection.execute "insert into hstores (tags) VALUES ('1=>2,2=>3')"
+    x = Hstore.first
+    assert_equal({ "1" => "2", "2" => "3" }, x.tags)
+  end
 
-    def test_comma
-      assert_cycle('a, b' => 'bar', '1"foo' => '2')
-    end
+  def test_create
+    assert_cycle("a" => "b", "1" => "2")
+  end
 
-    def test_arrow
-      assert_cycle('a=>b' => 'bar', '1"foo' => '2')
-    end
+  def test_nil
+    assert_cycle("a" => nil)
+  end
 
-    def test_quoting_special_characters
-      assert_cycle('ca' => 'cà', 'ac' => 'àc')
-    end
+  def test_quotes
+    assert_cycle("a" => 'b"ar', '1"foo' => "2")
+  end
 
-    def test_multiline
-      assert_cycle("a\nb" => "c\nd")
-    end
+  def test_whitespace
+    assert_cycle("a b" => "b ar", '1"foo' => "2")
+  end
 
-    class TagCollection
-      def initialize(hash); @hash = hash end
-      def to_hash; @hash end
-      def self.load(hash); new(hash) end
-      def self.dump(object); object.to_hash end
-    end
+  def test_backslash
+    assert_cycle('a\\b' => 'b\\ar', '1"foo' => "2")
+  end
 
-    class HstoreWithSerialize < Hstore
-      serialize :tags, TagCollection
-    end
+  def test_comma
+    assert_cycle("a, b" => "bar", '1"foo' => "2")
+  end
 
-    def test_hstore_with_serialized_attributes
-      HstoreWithSerialize.create! tags: TagCollection.new({"one" => "two"})
-      record = HstoreWithSerialize.first
-      assert_instance_of TagCollection, record.tags
-      assert_equal({"one" => "two"}, record.tags.to_hash)
-      record.tags = TagCollection.new("three" => "four")
-      record.save!
-      assert_equal({"three" => "four"}, HstoreWithSerialize.first.tags.to_hash)
-    end
+  def test_arrow
+    assert_cycle("a=>b" => "bar", '1"foo' => "2")
+  end
 
-    def test_clone_hstore_with_serialized_attributes
-      HstoreWithSerialize.create! tags: TagCollection.new({"one" => "two"})
-      record = HstoreWithSerialize.first
-      dupe = record.dup
-      assert_equal({"one" => "two"}, dupe.tags.to_hash)
-    end
+  def test_quoting_special_characters
+    assert_cycle("ca" => "cà", "ac" => "àc")
+  end
 
-    def test_schema_dump_with_shorthand
-      output = dump_table_schema("hstores")
-      assert_match %r[t\.hstore "tags",\s+default: {}], output
-    end
+  def test_multiline
+    assert_cycle("a\nb" => "c\nd")
+  end
+
+  class TagCollection
+    def initialize(hash); @hash = hash end
+    def to_hash; @hash end
+    def self.load(hash); new(hash) end
+    def self.dump(object); object.to_hash end
+  end
+
+  class HstoreWithSerialize < Hstore
+    serialize :tags, TagCollection
+  end
+
+  def test_hstore_with_serialized_attributes
+    HstoreWithSerialize.create! tags: TagCollection.new("one" => "two")
+    record = HstoreWithSerialize.first
+    assert_instance_of TagCollection, record.tags
+    assert_equal({ "one" => "two" }, record.tags.to_hash)
+    record.tags = TagCollection.new("three" => "four")
+    record.save!
+    assert_equal({ "three" => "four" }, HstoreWithSerialize.first.tags.to_hash)
+  end
 
-    private
+  def test_clone_hstore_with_serialized_attributes
+    HstoreWithSerialize.create! tags: TagCollection.new("one" => "two")
+    record = HstoreWithSerialize.first
+    dupe = record.dup
+    assert_equal({ "one" => "two" }, dupe.tags.to_hash)
+  end
+
+  def test_schema_dump_with_shorthand
+    output = dump_table_schema("hstores")
+    assert_match %r[t\.hstore "tags",\s+default: {}], output
+  end
+
+  def test_supports_to_unsafe_h_values
+    assert_equal("\"hi\"=>\"hi\"", @type.serialize(FakeParameters.new))
+  end
+
+  private
     def assert_array_cycle(array)
       # test creation
       x = Hstore.create!(payload: array)
@@ -338,16 +364,15 @@ if ActiveRecord::Base.connection.supports_extensions?
 
     def assert_cycle(hash)
       # test creation
-      x = Hstore.create!(:tags => hash)
+      x = Hstore.create!(tags: hash)
       x.reload
       assert_equal(hash, x.tags)
 
       # test updating
-      x = Hstore.create!(:tags => {})
+      x = Hstore.create!(tags: {})
       x.tags = hash
       x.save!
       x.reload
       assert_equal(hash, x.tags)
     end
-  end
 end
diff --git a/activerecord/test/cases/adapters/postgresql/infinity_test.rb b/activerecord/test/cases/adapters/postgresql/infinity_test.rb
index bfda933fa4..0b18c0c9d7 100644
--- a/activerecord/test/cases/adapters/postgresql/infinity_test.rb
+++ b/activerecord/test/cases/adapters/postgresql/infinity_test.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require "cases/helper"
 
 class PostgresqlInfinityTest < ActiveRecord::PostgreSQLTestCase
@@ -15,7 +17,7 @@ class PostgresqlInfinityTest < ActiveRecord::PostgreSQLTestCase
   end
 
   teardown do
-    @connection.drop_table 'postgresql_infinities', if_exists: true
+    @connection.drop_table "postgresql_infinities", if_exists: true
   end
 
   test "type casting infinity on a float column" do
@@ -25,12 +27,12 @@ class PostgresqlInfinityTest < ActiveRecord::PostgreSQLTestCase
   end
 
   test "type casting string on a float column" do
-    record = PostgresqlInfinity.new(float: 'Infinity')
+    record = PostgresqlInfinity.new(float: "Infinity")
     assert_equal Float::INFINITY, record.float
-    record = PostgresqlInfinity.new(float: '-Infinity')
+    record = PostgresqlInfinity.new(float: "-Infinity")
     assert_equal(-Float::INFINITY, record.float)
-    record = PostgresqlInfinity.new(float: 'NaN')
-    assert_send [record.float, :nan?]
+    record = PostgresqlInfinity.new(float: "NaN")
+    assert record.float.nan?, "Expected #{record.float} to be NaN"
   end
 
   test "update_all with infinity on a float column" do
diff --git a/activerecord/test/cases/adapters/postgresql/integer_test.rb b/activerecord/test/cases/adapters/postgresql/integer_test.rb
index b4e55964b9..3e45b057ff 100644
--- a/activerecord/test/cases/adapters/postgresql/integer_test.rb
+++ b/activerecord/test/cases/adapters/postgresql/integer_test.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require "cases/helper"
 require "active_support/core_ext/numeric/bytes"
 
diff --git a/activerecord/test/cases/adapters/postgresql/json_test.rb b/activerecord/test/cases/adapters/postgresql/json_test.rb
index 663de680b5..ee08841eb3 100644
--- a/activerecord/test/cases/adapters/postgresql/json_test.rb
+++ b/activerecord/test/cases/adapters/postgresql/json_test.rb
@@ -1,196 +1,37 @@
+# frozen_string_literal: true
+
 require "cases/helper"
-require 'support/schema_dumping_helper'
+require "cases/json_shared_test_cases"
 
 module PostgresqlJSONSharedTestCases
-  include SchemaDumpingHelper
-
-  class JsonDataType < ActiveRecord::Base
-    self.table_name = 'json_data_type'
-
-    store_accessor :settings, :resolution
-  end
+  include JSONSharedTestCases
 
   def setup
-    @connection = ActiveRecord::Base.connection
-    begin
-      @connection.create_table('json_data_type') do |t|
-        t.public_send column_type, 'payload', default: {} # t.json 'payload', default: {}
-        t.public_send column_type, 'settings'             # t.json 'settings'
-      end
-    rescue ActiveRecord::StatementInvalid
-      skip "do not test on PostgreSQL without #{column_type} type."
+    super
+    @connection.create_table("json_data_type") do |t|
+      t.public_send column_type, "payload", default: {} # t.json 'payload', default: {}
+      t.public_send column_type, "settings"             # t.json 'settings'
+      t.public_send column_type, "objects", array: true # t.json 'objects', array: true
     end
-  end
-
-  def teardown
-    @connection.drop_table :json_data_type, if_exists: true
-    JsonDataType.reset_column_information
-  end
-
-  def test_column
-    column = JsonDataType.columns_hash["payload"]
-    assert_equal column_type, column.type
-    assert_equal column_type.to_s, column.sql_type
-    assert_not column.array?
-
-    type = JsonDataType.type_for_attribute("payload")
-    assert_not type.binary?
+  rescue ActiveRecord::StatementInvalid
+    skip "do not test on PostgreSQL without #{column_type} type."
   end
 
   def test_default
-    @connection.add_column 'json_data_type', 'permissions', column_type, default: {"users": "read", "posts": ["read", "write"]}
-    JsonDataType.reset_column_information
-
-    assert_equal({"users"=>"read", "posts"=>["read", "write"]}, JsonDataType.column_defaults['permissions'])
-    assert_equal({"users"=>"read", "posts"=>["read", "write"]}, JsonDataType.new.permissions)
-  ensure
-    JsonDataType.reset_column_information
-  end
-
-  def test_change_table_supports_json
-    @connection.transaction do
-      @connection.change_table('json_data_type') do |t|
-        t.public_send column_type, 'users', default: '{}' # t.json 'users', default: '{}'
-      end
-      JsonDataType.reset_column_information
-      column = JsonDataType.columns_hash['users']
-      assert_equal column_type, column.type
-
-      raise ActiveRecord::Rollback # reset the schema change
-    end
-  ensure
-    JsonDataType.reset_column_information
-  end
-
-  def test_schema_dumping
-    output = dump_table_schema("json_data_type")
-    assert_match(/t\.#{column_type.to_s}\s+"payload",\s+default: {}/, output)
-  end
-
-  def test_cast_value_on_write
-    x = JsonDataType.new payload: {"string" => "foo", :symbol => :bar}
-    assert_equal({"string" => "foo", :symbol => :bar}, x.payload_before_type_cast)
-    assert_equal({"string" => "foo", "symbol" => "bar"}, x.payload)
-    x.save
-    assert_equal({"string" => "foo", "symbol" => "bar"}, x.reload.payload)
-  end
-
-  def test_type_cast_json
-    type = JsonDataType.type_for_attribute("payload")
-
-    data = "{\"a_key\":\"a_value\"}"
-    hash = type.deserialize(data)
-    assert_equal({'a_key' => 'a_value'}, hash)
-    assert_equal({'a_key' => 'a_value'}, type.deserialize(data))
-
-    assert_equal({}, type.deserialize("{}"))
-    assert_equal({'key'=>nil}, type.deserialize('{"key": null}'))
-    assert_equal({'c'=>'}','"a"'=>'b "a b'}, type.deserialize(%q({"c":"}", "\"a\"":"b \"a b"})))
-  end
-
-  def test_rewrite
-    @connection.execute "insert into json_data_type (payload) VALUES ('{\"k\":\"v\"}')"
-    x = JsonDataType.first
-    x.payload = { '"a\'' => 'b' }
-    assert x.save!
-  end
-
-  def test_select
-    @connection.execute "insert into json_data_type (payload) VALUES ('{\"k\":\"v\"}')"
-    x = JsonDataType.first
-    assert_equal({'k' => 'v'}, x.payload)
-  end
-
-  def test_select_multikey
-    @connection.execute %q|insert into json_data_type (payload) VALUES ('{"k1":"v1", "k2":"v2", "k3":[1,2,3]}')|
-    x = JsonDataType.first
-    assert_equal({'k1' => 'v1', 'k2' => 'v2', 'k3' => [1,2,3]}, x.payload)
-  end
-
-  def test_null_json
-    @connection.execute %q|insert into json_data_type (payload) VALUES(null)|
-    x = JsonDataType.first
-    assert_equal(nil, x.payload)
-  end
+    @connection.add_column "json_data_type", "permissions", column_type, default: { "users": "read", "posts": ["read", "write"] }
+    klass.reset_column_information
 
-  def test_select_array_json_value
-    @connection.execute %q|insert into json_data_type (payload) VALUES ('["v0",{"k1":"v1"}]')|
-    x = JsonDataType.first
-    assert_equal(['v0', {'k1' => 'v1'}], x.payload)
+    assert_equal({ "users" => "read", "posts" => ["read", "write"] }, klass.column_defaults["permissions"])
+    assert_equal({ "users" => "read", "posts" => ["read", "write"] }, klass.new.permissions)
   end
 
-  def test_rewrite_array_json_value
-    @connection.execute %q|insert into json_data_type (payload) VALUES ('["v0",{"k1":"v1"}]')|
-    x = JsonDataType.first
-    x.payload = ['v1', {'k2' => 'v2'}, 'v3']
-    assert x.save!
-  end
-
-  def test_with_store_accessors
-    x = JsonDataType.new(resolution: "320×480")
-    assert_equal "320×480", x.resolution
-
-    x.save!
-    x = JsonDataType.first
-    assert_equal "320×480", x.resolution
-
-    x.resolution = "640×1136"
+  def test_deserialize_with_array
+    x = klass.new(objects: ["foo" => "bar"])
+    assert_equal ["foo" => "bar"], x.objects
     x.save!
-
-    x = JsonDataType.first
-    assert_equal "640×1136", x.resolution
-  end
-
-  def test_duplication_with_store_accessors
-    x = JsonDataType.new(resolution: "320×480")
-    assert_equal "320×480", x.resolution
-
-    y = x.dup
-    assert_equal "320×480", y.resolution
-  end
-
-  def test_yaml_round_trip_with_store_accessors
-    x = JsonDataType.new(resolution: "320×480")
-    assert_equal "320×480", x.resolution
-
-    y = YAML.load(YAML.dump(x))
-    assert_equal "320×480", y.resolution
-  end
-
-  def test_changes_in_place
-    json = JsonDataType.new
-    assert_not json.changed?
-
-    json.payload = { 'one' => 'two' }
-    assert json.changed?
-    assert json.payload_changed?
-
-    json.save!
-    assert_not json.changed?
-
-    json.payload['three'] = 'four'
-    assert json.payload_changed?
-
-    json.save!
-    json.reload
-
-    assert_equal({ 'one' => 'two', 'three' => 'four' }, json.payload)
-    assert_not json.changed?
-  end
-
-  def test_assigning_string_literal
-    json = JsonDataType.create(payload: "foo")
-    assert_equal "foo", json.payload
-  end
-
-  def test_assigning_number
-    json = JsonDataType.create(payload: 1.234)
-    assert_equal 1.234, json.payload
-  end
-
-  def test_assigning_boolean
-    json = JsonDataType.create(payload: true)
-    assert_equal true, json.payload
+    assert_equal ["foo" => "bar"], x.objects
+    x.reload
+    assert_equal ["foo" => "bar"], x.objects
   end
 end
 
diff --git a/activerecord/test/cases/adapters/postgresql/ltree_test.rb b/activerecord/test/cases/adapters/postgresql/ltree_test.rb
index 56516c82b4..eca29f2892 100644
--- a/activerecord/test/cases/adapters/postgresql/ltree_test.rb
+++ b/activerecord/test/cases/adapters/postgresql/ltree_test.rb
@@ -1,20 +1,22 @@
+# frozen_string_literal: true
+
 require "cases/helper"
-require 'support/schema_dumping_helper'
+require "support/schema_dumping_helper"
 
 class PostgresqlLtreeTest < ActiveRecord::PostgreSQLTestCase
   include SchemaDumpingHelper
   class Ltree < ActiveRecord::Base
-    self.table_name = 'ltrees'
+    self.table_name = "ltrees"
   end
 
   def setup
     @connection = ActiveRecord::Base.connection
 
-    enable_extension!('ltree', @connection)
+    enable_extension!("ltree", @connection)
 
     @connection.transaction do
-      @connection.create_table('ltrees') do |t|
-        t.ltree 'path'
+      @connection.create_table("ltrees") do |t|
+        t.ltree "path"
       end
     end
   rescue ActiveRecord::StatementInvalid
@@ -22,28 +24,28 @@ class PostgresqlLtreeTest < ActiveRecord::PostgreSQLTestCase
   end
 
   teardown do
-    @connection.drop_table 'ltrees', if_exists: true
+    @connection.drop_table "ltrees", if_exists: true
   end
 
   def test_column
-    column = Ltree.columns_hash['path']
+    column = Ltree.columns_hash["path"]
     assert_equal :ltree, column.type
     assert_equal "ltree", column.sql_type
     assert_not column.array?
 
-    type = Ltree.type_for_attribute('path')
+    type = Ltree.type_for_attribute("path")
     assert_not type.binary?
   end
 
   def test_write
-    ltree = Ltree.new(path: '1.2.3.4')
+    ltree = Ltree.new(path: "1.2.3.4")
     assert ltree.save!
   end
 
   def test_select
     @connection.execute "insert into ltrees (path) VALUES ('1.2.3')"
     ltree = Ltree.first
-    assert_equal '1.2.3', ltree.path
+    assert_equal "1.2.3", ltree.path
   end
 
   def test_schema_dump_with_shorthand
diff --git a/activerecord/test/cases/adapters/postgresql/money_test.rb b/activerecord/test/cases/adapters/postgresql/money_test.rb
index c031178479..cc10890fa8 100644
--- a/activerecord/test/cases/adapters/postgresql/money_test.rb
+++ b/activerecord/test/cases/adapters/postgresql/money_test.rb
@@ -1,5 +1,7 @@
+# frozen_string_literal: true
+
 require "cases/helper"
-require 'support/schema_dumping_helper'
+require "support/schema_dumping_helper"
 
 class PostgresqlMoneyTest < ActiveRecord::PostgreSQLTestCase
   include SchemaDumpingHelper
@@ -9,14 +11,14 @@ class PostgresqlMoneyTest < ActiveRecord::PostgreSQLTestCase
   setup do
     @connection = ActiveRecord::Base.connection
     @connection.execute("set lc_monetary = 'C'")
-    @connection.create_table('postgresql_moneys', force: true) do |t|
+    @connection.create_table("postgresql_moneys", force: true) do |t|
       t.money "wealth"
       t.money "depth", default: "150.55"
     end
   end
 
   teardown do
-    @connection.drop_table 'postgresql_moneys', if_exists: true
+    @connection.drop_table "postgresql_moneys", if_exists: true
   end
 
   def test_column
@@ -31,8 +33,8 @@ class PostgresqlMoneyTest < ActiveRecord::PostgreSQLTestCase
   end
 
   def test_default
-    assert_equal BigDecimal.new("150.55"), PostgresqlMoney.column_defaults['depth']
-    assert_equal BigDecimal.new("150.55"), PostgresqlMoney.new.depth
+    assert_equal BigDecimal("150.55"), PostgresqlMoney.column_defaults["depth"]
+    assert_equal BigDecimal("150.55"), PostgresqlMoney.new.depth
   end
 
   def test_money_values
@@ -46,11 +48,11 @@ class PostgresqlMoneyTest < ActiveRecord::PostgreSQLTestCase
   end
 
   def test_money_type_cast
-    type = PostgresqlMoney.type_for_attribute('wealth')
-    assert_equal(12345678.12, type.cast("$12,345,678.12"))
-    assert_equal(12345678.12, type.cast("$12.345.678,12"))
-    assert_equal(-1.15, type.cast("-$1.15"))
-    assert_equal(-2.25, type.cast("($2.25)"))
+    type = PostgresqlMoney.type_for_attribute("wealth")
+    assert_equal(12345678.12, type.cast("$12,345,678.12".dup))
+    assert_equal(12345678.12, type.cast("$12.345.678,12".dup))
+    assert_equal(-1.15, type.cast("-$1.15".dup))
+    assert_equal(-2.25, type.cast("($2.25)".dup))
   end
 
   def test_schema_dumping
@@ -60,10 +62,10 @@ class PostgresqlMoneyTest < ActiveRecord::PostgreSQLTestCase
   end
 
   def test_create_and_update_money
-    money = PostgresqlMoney.create(wealth: "987.65")
+    money = PostgresqlMoney.create(wealth: "987.65".dup)
     assert_equal 987.65, money.wealth
 
-    new_value = BigDecimal.new('123.45')
+    new_value = BigDecimal("123.45")
     money.wealth = new_value
     money.save!
     money.reload
@@ -80,7 +82,7 @@ class PostgresqlMoneyTest < ActiveRecord::PostgreSQLTestCase
 
   def test_update_all_with_money_big_decimal
     money = PostgresqlMoney.create!
-    PostgresqlMoney.update_all(wealth: '123.45'.to_d)
+    PostgresqlMoney.update_all(wealth: "123.45".to_d)
     money.reload
 
     assert_equal 123.45, money.wealth
diff --git a/activerecord/test/cases/adapters/postgresql/network_test.rb b/activerecord/test/cases/adapters/postgresql/network_test.rb
index fe6ee4e2d9..f461544a85 100644
--- a/activerecord/test/cases/adapters/postgresql/network_test.rb
+++ b/activerecord/test/cases/adapters/postgresql/network_test.rb
@@ -1,5 +1,7 @@
+# frozen_string_literal: true
+
 require "cases/helper"
-require 'support/schema_dumping_helper'
+require "support/schema_dumping_helper"
 
 class PostgresqlNetworkTest < ActiveRecord::PostgreSQLTestCase
   include SchemaDumpingHelper
@@ -7,15 +9,15 @@ class PostgresqlNetworkTest < ActiveRecord::PostgreSQLTestCase
 
   setup do
     @connection = ActiveRecord::Base.connection
-    @connection.create_table('postgresql_network_addresses', force: true) do |t|
-      t.inet 'inet_address', default: "192.168.1.1"
-      t.cidr 'cidr_address', default: "192.168.1.0/24"
-      t.macaddr 'mac_address', default: "ff:ff:ff:ff:ff:ff"
+    @connection.create_table("postgresql_network_addresses", force: true) do |t|
+      t.inet "inet_address", default: "192.168.1.1"
+      t.cidr "cidr_address", default: "192.168.1.0/24"
+      t.macaddr "mac_address", default: "ff:ff:ff:ff:ff:ff"
     end
   end
 
   teardown do
-    @connection.drop_table 'postgresql_network_addresses', if_exists: true
+    @connection.drop_table "postgresql_network_addresses", if_exists: true
   end
 
   def test_cidr_column
@@ -49,33 +51,33 @@ class PostgresqlNetworkTest < ActiveRecord::PostgreSQLTestCase
   end
 
   def test_network_types
-    PostgresqlNetworkAddress.create(cidr_address: '192.168.0.0/24',
-                                    inet_address: '172.16.1.254/32',
-                                    mac_address: '01:23:45:67:89:0a')
+    PostgresqlNetworkAddress.create(cidr_address: "192.168.0.0/24",
+                                    inet_address: "172.16.1.254/32",
+                                    mac_address: "01:23:45:67:89:0a")
 
     address = PostgresqlNetworkAddress.first
-    assert_equal IPAddr.new('192.168.0.0/24'), address.cidr_address
-    assert_equal IPAddr.new('172.16.1.254'), address.inet_address
-    assert_equal '01:23:45:67:89:0a', address.mac_address
+    assert_equal IPAddr.new("192.168.0.0/24"), address.cidr_address
+    assert_equal IPAddr.new("172.16.1.254"), address.inet_address
+    assert_equal "01:23:45:67:89:0a", address.mac_address
 
-    address.cidr_address = '10.1.2.3/32'
-    address.inet_address = '10.0.0.0/8'
-    address.mac_address = 'bc:de:f0:12:34:56'
+    address.cidr_address = "10.1.2.3/32"
+    address.inet_address = "10.0.0.0/8"
+    address.mac_address = "bc:de:f0:12:34:56"
 
     address.save!
     assert address.reload
-    assert_equal IPAddr.new('10.1.2.3/32'), address.cidr_address
-    assert_equal IPAddr.new('10.0.0.0/8'), address.inet_address
-    assert_equal 'bc:de:f0:12:34:56', address.mac_address
+    assert_equal IPAddr.new("10.1.2.3/32"), address.cidr_address
+    assert_equal IPAddr.new("10.0.0.0/8"), address.inet_address
+    assert_equal "bc:de:f0:12:34:56", address.mac_address
   end
 
   def test_invalid_network_address
-    invalid_address = PostgresqlNetworkAddress.new(cidr_address: 'invalid addr',
-                                                   inet_address: 'invalid addr')
+    invalid_address = PostgresqlNetworkAddress.new(cidr_address: "invalid addr",
+                                                   inet_address: "invalid addr")
     assert_nil invalid_address.cidr_address
     assert_nil invalid_address.inet_address
-    assert_equal 'invalid addr', invalid_address.cidr_address_before_type_cast
-    assert_equal 'invalid addr', invalid_address.inet_address_before_type_cast
+    assert_equal "invalid addr", invalid_address.cidr_address_before_type_cast
+    assert_equal "invalid addr", invalid_address.inet_address_before_type_cast
     assert invalid_address.save
 
     invalid_address.reload
diff --git a/activerecord/test/cases/adapters/postgresql/numbers_test.rb b/activerecord/test/cases/adapters/postgresql/numbers_test.rb
index ba7e7dc9a3..b53a12254d 100644
--- a/activerecord/test/cases/adapters/postgresql/numbers_test.rb
+++ b/activerecord/test/cases/adapters/postgresql/numbers_test.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require "cases/helper"
 
 class PostgresqlNumberTest < ActiveRecord::PostgreSQLTestCase
@@ -5,14 +7,14 @@ class PostgresqlNumberTest < ActiveRecord::PostgreSQLTestCase
 
   setup do
     @connection = ActiveRecord::Base.connection
-    @connection.create_table('postgresql_numbers', force: true) do |t|
-      t.column 'single', 'REAL'
-      t.column 'double', 'DOUBLE PRECISION'
+    @connection.create_table("postgresql_numbers", force: true) do |t|
+      t.column "single", "REAL"
+      t.column "double", "DOUBLE PRECISION"
     end
   end
 
   teardown do
-    @connection.drop_table 'postgresql_numbers', if_exists: true
+    @connection.drop_table "postgresql_numbers", if_exists: true
   end
 
   def test_data_type
@@ -31,7 +33,7 @@ class PostgresqlNumberTest < ActiveRecord::PostgreSQLTestCase
     assert_equal 123456.789, first.double
     assert_equal(-::Float::INFINITY, second.single)
     assert_equal ::Float::INFINITY, second.double
-    assert_send [third.double, :nan?]
+    assert third.double.nan?, "Expected #{third.double} to be NaN"
   end
 
   def test_update
diff --git a/activerecord/test/cases/adapters/postgresql/postgresql_adapter_test.rb b/activerecord/test/cases/adapters/postgresql/postgresql_adapter_test.rb
index 9832df7839..1951230c8a 100644
--- a/activerecord/test/cases/adapters/postgresql/postgresql_adapter_test.rb
+++ b/activerecord/test/cases/adapters/postgresql/postgresql_adapter_test.rb
@@ -1,6 +1,8 @@
+# frozen_string_literal: true
+
 require "cases/helper"
-require 'support/ddl_helper'
-require 'support/connection_helper'
+require "support/ddl_helper"
+require "support/connection_helper"
 
 module ActiveRecord
   module ConnectionAdapters
@@ -15,163 +17,140 @@ module ActiveRecord
 
       def test_bad_connection
         assert_raise ActiveRecord::NoDatabaseError do
-          configuration = ActiveRecord::Base.configurations['arunit'].merge(database: 'should_not_exist-cinco-dog-db')
+          configuration = ActiveRecord::Base.configurations["arunit"].merge(database: "should_not_exist-cinco-dog-db")
           connection = ActiveRecord::Base.postgresql_connection(configuration)
-          connection.exec_query('SELECT 1')
-        end
-      end
-
-      def test_valid_column
-        with_example_table do
-          column = @connection.columns('ex').find { |col| col.name == 'id' }
-          assert @connection.valid_type?(column.type)
+          connection.exec_query("SELECT 1")
         end
       end
 
-      def test_invalid_column
-        assert_not @connection.valid_type?(:foobar)
-      end
-
       def test_primary_key
         with_example_table do
-          assert_equal 'id', @connection.primary_key('ex')
+          assert_equal "id", @connection.primary_key("ex")
         end
       end
 
       def test_primary_key_works_tables_containing_capital_letters
-        assert_equal 'id', @connection.primary_key('CamelCase')
+        assert_equal "id", @connection.primary_key("CamelCase")
       end
 
       def test_non_standard_primary_key
-        with_example_table 'data character varying(255) primary key' do
-          assert_equal 'data', @connection.primary_key('ex')
+        with_example_table "data character varying(255) primary key" do
+          assert_equal "data", @connection.primary_key("ex")
         end
       end
 
       def test_primary_key_returns_nil_for_no_pk
-        with_example_table 'id integer' do
-          assert_nil @connection.primary_key('ex')
-        end
-      end
-
-      def test_primary_key_raises_error_if_table_not_found
-        assert_raises(ActiveRecord::StatementInvalid) do
-          @connection.primary_key('unobtainium')
+        with_example_table "id integer" do
+          assert_nil @connection.primary_key("ex")
         end
       end
 
       def test_exec_insert_with_returning_disabled
         connection = connection_without_insert_returning
-        result = connection.exec_insert("insert into postgresql_partitioned_table_parent (number) VALUES (1)", nil, [], 'id', 'postgresql_partitioned_table_parent_id_seq')
-        expect = connection.query('select max(id) from postgresql_partitioned_table_parent').first.first
+        result = connection.exec_insert("insert into postgresql_partitioned_table_parent (number) VALUES (1)", nil, [], "id", "postgresql_partitioned_table_parent_id_seq")
+        expect = connection.query("select max(id) from postgresql_partitioned_table_parent").first.first
         assert_equal expect.to_i, result.rows.first.first
       end
 
       def test_exec_insert_with_returning_disabled_and_no_sequence_name_given
         connection = connection_without_insert_returning
-        result = connection.exec_insert("insert into postgresql_partitioned_table_parent (number) VALUES (1)", nil, [], 'id')
-        expect = connection.query('select max(id) from postgresql_partitioned_table_parent').first.first
+        result = connection.exec_insert("insert into postgresql_partitioned_table_parent (number) VALUES (1)", nil, [], "id")
+        expect = connection.query("select max(id) from postgresql_partitioned_table_parent").first.first
         assert_equal expect.to_i, result.rows.first.first
       end
 
       def test_exec_insert_default_values_with_returning_disabled_and_no_sequence_name_given
         connection = connection_without_insert_returning
-        result = connection.exec_insert("insert into postgresql_partitioned_table_parent DEFAULT VALUES", nil, [], 'id')
-        expect = connection.query('select max(id) from postgresql_partitioned_table_parent').first.first
+        result = connection.exec_insert("insert into postgresql_partitioned_table_parent DEFAULT VALUES", nil, [], "id")
+        expect = connection.query("select max(id) from postgresql_partitioned_table_parent").first.first
         assert_equal expect.to_i, result.rows.first.first
       end
 
       def test_exec_insert_default_values_quoted_schema_with_returning_disabled_and_no_sequence_name_given
         connection = connection_without_insert_returning
-        result = connection.exec_insert('insert into "public"."postgresql_partitioned_table_parent" DEFAULT VALUES', nil, [], 'id')
-        expect = connection.query('select max(id) from postgresql_partitioned_table_parent').first.first
+        result = connection.exec_insert('insert into "public"."postgresql_partitioned_table_parent" DEFAULT VALUES', nil, [], "id")
+        expect = connection.query("select max(id) from postgresql_partitioned_table_parent").first.first
         assert_equal expect.to_i, result.rows.first.first
       end
 
-      def test_sql_for_insert_with_returning_disabled
-        connection = connection_without_insert_returning
-        sql, binds = connection.sql_for_insert('sql', nil, nil, nil, 'binds')
-        assert_equal ['sql', 'binds'], [sql, binds]
-      end
-
       def test_serial_sequence
-        assert_equal 'public.accounts_id_seq',
-          @connection.serial_sequence('accounts', 'id')
+        assert_equal "public.accounts_id_seq",
+          @connection.serial_sequence("accounts", "id")
 
         assert_raises(ActiveRecord::StatementInvalid) do
-          @connection.serial_sequence('zomg', 'id')
+          @connection.serial_sequence("zomg", "id")
         end
       end
 
       def test_default_sequence_name
-        assert_equal 'public.accounts_id_seq',
-          @connection.default_sequence_name('accounts', 'id')
+        assert_equal "public.accounts_id_seq",
+          @connection.default_sequence_name("accounts", "id")
 
-        assert_equal 'public.accounts_id_seq',
-          @connection.default_sequence_name('accounts')
+        assert_equal "public.accounts_id_seq",
+          @connection.default_sequence_name("accounts")
       end
 
       def test_default_sequence_name_bad_table
-        assert_equal 'zomg_id_seq',
-          @connection.default_sequence_name('zomg', 'id')
+        assert_equal "zomg_id_seq",
+          @connection.default_sequence_name("zomg", "id")
 
-        assert_equal 'zomg_id_seq',
-          @connection.default_sequence_name('zomg')
+        assert_equal "zomg_id_seq",
+          @connection.default_sequence_name("zomg")
       end
 
       def test_pk_and_sequence_for
         with_example_table do
-          pk, seq = @connection.pk_and_sequence_for('ex')
-          assert_equal 'id', pk
-          assert_equal @connection.default_sequence_name('ex', 'id'), seq.to_s
+          pk, seq = @connection.pk_and_sequence_for("ex")
+          assert_equal "id", pk
+          assert_equal @connection.default_sequence_name("ex", "id"), seq.to_s
         end
       end
 
       def test_pk_and_sequence_for_with_non_standard_primary_key
-        with_example_table 'code serial primary key' do
-          pk, seq = @connection.pk_and_sequence_for('ex')
-          assert_equal 'code', pk
-          assert_equal @connection.default_sequence_name('ex', 'code'), seq.to_s
+        with_example_table "code serial primary key" do
+          pk, seq = @connection.pk_and_sequence_for("ex")
+          assert_equal "code", pk
+          assert_equal @connection.default_sequence_name("ex", "code"), seq.to_s
         end
       end
 
       def test_pk_and_sequence_for_returns_nil_if_no_seq
-        with_example_table 'id integer primary key' do
-          assert_nil @connection.pk_and_sequence_for('ex')
+        with_example_table "id integer primary key" do
+          assert_nil @connection.pk_and_sequence_for("ex")
         end
       end
 
       def test_pk_and_sequence_for_returns_nil_if_no_pk
-        with_example_table 'id integer' do
-          assert_nil @connection.pk_and_sequence_for('ex')
+        with_example_table "id integer" do
+          assert_nil @connection.pk_and_sequence_for("ex")
         end
       end
 
       def test_pk_and_sequence_for_returns_nil_if_table_not_found
-        assert_nil @connection.pk_and_sequence_for('unobtainium')
+        assert_nil @connection.pk_and_sequence_for("unobtainium")
       end
 
       def test_pk_and_sequence_for_with_collision_pg_class_oid
-        @connection.exec_query('create table ex(id serial primary key)')
-        @connection.exec_query('create table ex2(id serial primary key)')
+        @connection.exec_query("create table ex(id serial primary key)")
+        @connection.exec_query("create table ex2(id serial primary key)")
 
         correct_depend_record = [
           "'pg_class'::regclass",
           "'ex_id_seq'::regclass",
-          '0',
+          "0",
           "'pg_class'::regclass",
           "'ex'::regclass",
-          '1',
+          "1",
           "'a'"
         ]
 
         collision_depend_record = [
           "'pg_attrdef'::regclass",
           "'ex2_id_seq'::regclass",
-          '0',
+          "0",
           "'pg_class'::regclass",
           "'ex'::regclass",
-          '1',
+          "1",
           "'a'"
         ]
 
@@ -185,15 +164,15 @@ module ActiveRecord
           "INSERT INTO pg_depend VALUES(#{correct_depend_record.join(',')})"
         )
 
-        seq = @connection.pk_and_sequence_for('ex').last
+        seq = @connection.pk_and_sequence_for("ex").last
         assert_equal PostgreSQL::Name.new("public", "ex_id_seq"), seq
 
         @connection.exec_query(
           "DELETE FROM pg_depend WHERE objid = 'ex2_id_seq'::regclass AND refobjid = 'ex'::regclass AND deptype = 'a'"
         )
       ensure
-        @connection.drop_table 'ex', if_exists: true
-        @connection.drop_table 'ex2', if_exists: true
+        @connection.drop_table "ex", if_exists: true
+        @connection.drop_table "ex2", if_exists: true
       end
 
       def test_table_alias_length
@@ -204,74 +183,77 @@ module ActiveRecord
 
       def test_exec_no_binds
         with_example_table do
-          result = @connection.exec_query('SELECT id, data FROM ex')
+          result = @connection.exec_query("SELECT id, data FROM ex")
           assert_equal 0, result.rows.length
           assert_equal 2, result.columns.length
           assert_equal %w{ id data }, result.columns
 
-          string = @connection.quote('foo')
+          string = @connection.quote("foo")
           @connection.exec_query("INSERT INTO ex (id, data) VALUES (1, #{string})")
-          result = @connection.exec_query('SELECT id, data FROM ex')
+          result = @connection.exec_query("SELECT id, data FROM ex")
           assert_equal 1, result.rows.length
           assert_equal 2, result.columns.length
 
-          assert_equal [[1, 'foo']], result.rows
+          assert_equal [[1, "foo"]], result.rows
         end
       end
 
       if ActiveRecord::Base.connection.prepared_statements
         def test_exec_with_binds
           with_example_table do
-            string = @connection.quote('foo')
+            string = @connection.quote("foo")
             @connection.exec_query("INSERT INTO ex (id, data) VALUES (1, #{string})")
 
             bind = Relation::QueryAttribute.new("id", 1, Type::Value.new)
-            result = @connection.exec_query('SELECT id, data FROM ex WHERE id = $1', nil, [bind])
+            result = @connection.exec_query("SELECT id, data FROM ex WHERE id = $1", nil, [bind])
 
             assert_equal 1, result.rows.length
             assert_equal 2, result.columns.length
 
-            assert_equal [[1, 'foo']], result.rows
+            assert_equal [[1, "foo"]], result.rows
           end
         end
 
         def test_exec_typecasts_bind_vals
           with_example_table do
-            string = @connection.quote('foo')
+            string = @connection.quote("foo")
             @connection.exec_query("INSERT INTO ex (id, data) VALUES (1, #{string})")
 
             bind = Relation::QueryAttribute.new("id", "1-fuu", Type::Integer.new)
-            result = @connection.exec_query('SELECT id, data FROM ex WHERE id = $1', nil, [bind])
+            result = @connection.exec_query("SELECT id, data FROM ex WHERE id = $1", nil, [bind])
 
             assert_equal 1, result.rows.length
             assert_equal 2, result.columns.length
 
-            assert_equal [[1, 'foo']], result.rows
+            assert_equal [[1, "foo"]], result.rows
           end
         end
       end
 
       def test_partial_index
         with_example_table do
-          @connection.add_index 'ex', %w{ id number }, :name => 'partial', :where => "number > 100"
-          index = @connection.indexes('ex').find { |idx| idx.name == 'partial' }
+          @connection.add_index "ex", %w{ id number }, name: "partial", where: "number > 100"
+          index = @connection.indexes("ex").find { |idx| idx.name == "partial" }
           assert_equal "(number > 100)", index.where
         end
       end
 
       def test_expression_index
         with_example_table do
-          @connection.add_index 'ex', 'mod(id, 10), abs(number)', name: 'expression'
-          index = @connection.indexes('ex').find { |idx| idx.name == 'expression' }
-          assert_equal 'mod(id, 10), abs(number)', index.columns
+          @connection.add_index "ex", "mod(id, 10), abs(number)", name: "expression"
+          index = @connection.indexes("ex").find { |idx| idx.name == "expression" }
+          assert_equal "mod(id, 10), abs(number)", index.columns
         end
       end
 
       def test_index_with_opclass
         with_example_table do
-          @connection.add_index 'ex', 'data varchar_pattern_ops', name: 'with_opclass'
-          index = @connection.indexes('ex').find { |idx| idx.name == 'with_opclass' }
-          assert_equal 'data varchar_pattern_ops', index.columns
+          @connection.add_index "ex", "data", opclass: "varchar_pattern_ops"
+          index = @connection.indexes("ex").find { |idx| idx.name == "index_ex_on_data" }
+          assert_equal ["data"], index.columns
+
+          @connection.remove_index "ex", "data"
+          assert_not @connection.indexes("ex").find { |idx| idx.name == "index_ex_on_data" }
         end
       end
 
@@ -292,8 +274,8 @@ module ActiveRecord
 
       def test_columns_for_distinct_with_case
         assert_equal(
-          'posts.id, CASE WHEN author.is_active THEN UPPER(author.name) ELSE UPPER(author.email) END AS alias_0',
-          @connection.columns_for_distinct('posts.id',
+          "posts.id, CASE WHEN author.is_active THEN UPPER(author.name) ELSE UPPER(author.email) END AS alias_0",
+          @connection.columns_for_distinct("posts.id",
             ["CASE WHEN author.is_active THEN UPPER(author.name) ELSE UPPER(author.email) END"])
         )
       end
@@ -344,29 +326,35 @@ module ActiveRecord
         reset_connection
       end
 
-      def test_only_reload_type_map_once_for_every_unknown_type
+      def test_only_reload_type_map_once_for_every_unrecognized_type
+        reset_connection
+        connection = ActiveRecord::Base.connection
+
         silence_warnings do
           assert_queries 2, ignore_none: true do
-            @connection.select_all "SELECT NULL::anyelement"
+            connection.select_all "select 'pg_catalog.pg_class'::regclass"
           end
           assert_queries 1, ignore_none: true do
-            @connection.select_all "SELECT NULL::anyelement"
+            connection.select_all "select 'pg_catalog.pg_class'::regclass"
           end
           assert_queries 2, ignore_none: true do
-            @connection.select_all "SELECT NULL::anyarray"
+            connection.select_all "SELECT NULL::anyarray"
           end
         end
       ensure
         reset_connection
       end
 
-      def test_only_warn_on_first_encounter_of_unknown_oid
+      def test_only_warn_on_first_encounter_of_unrecognized_oid
+        reset_connection
+        connection = ActiveRecord::Base.connection
+
         warning = capture(:stderr) {
-          @connection.select_all "SELECT NULL::anyelement"
-          @connection.select_all "SELECT NULL::anyelement"
-          @connection.select_all "SELECT NULL::anyelement"
+          connection.select_all "select 'pg_catalog.pg_class'::regclass"
+          connection.select_all "select 'pg_catalog.pg_class'::regclass"
+          connection.select_all "select 'pg_catalog.pg_class'::regclass"
         }
-        assert_match(/\Aunknown OID \d+: failed to recognize type of 'anyelement'. It will be treated as String.\n\z/, warning)
+        assert_match(/\Aunknown OID \d+: failed to recognize type of 'regclass'\. It will be treated as String\.\n\z/, warning)
       ensure
         reset_connection
       end
@@ -374,7 +362,7 @@ module ActiveRecord
       def test_unparsed_defaults_are_at_least_set_when_saving
         with_example_table "id SERIAL PRIMARY KEY, number INTEGER NOT NULL DEFAULT (4 + 4) * 2 / 4" do
           number_klass = Class.new(ActiveRecord::Base) do
-            self.table_name = 'ex'
+            self.table_name = "ex"
           end
           column = number_klass.columns_hash["number"]
           assert_nil column.default
@@ -390,13 +378,13 @@ module ActiveRecord
 
       private
 
-      def with_example_table(definition = 'id serial primary key, number integer, data character varying(255)', &block)
-        super(@connection, 'ex', definition, &block)
-      end
+        def with_example_table(definition = "id serial primary key, number integer, data character varying(255)", &block)
+          super(@connection, "ex", definition, &block)
+        end
 
-      def connection_without_insert_returning
-        ActiveRecord::Base.postgresql_connection(ActiveRecord::Base.configurations['arunit'].merge(:insert_returning => false))
-      end
+        def connection_without_insert_returning
+          ActiveRecord::Base.postgresql_connection(ActiveRecord::Base.configurations["arunit"].merge(insert_returning: false))
+        end
     end
   end
 end
diff --git a/activerecord/test/cases/adapters/postgresql/prepared_statements_disabled_test.rb b/activerecord/test/cases/adapters/postgresql/prepared_statements_disabled_test.rb
new file mode 100644
index 0000000000..f7478b50c3
--- /dev/null
+++ b/activerecord/test/cases/adapters/postgresql/prepared_statements_disabled_test.rb
@@ -0,0 +1,27 @@
+# frozen_string_literal: true
+
+require "cases/helper"
+require "models/computer"
+require "models/developer"
+
+class PreparedStatementsDisabledTest < ActiveRecord::PostgreSQLTestCase
+  fixtures :developers
+
+  def setup
+    @conn = ActiveRecord::Base.establish_connection :arunit_without_prepared_statements
+  end
+
+  def teardown
+    @conn.release_connection
+    ActiveRecord::Base.establish_connection :arunit
+  end
+
+  def test_select_query_works_even_when_prepared_statements_are_disabled
+    assert_not Developer.connection.prepared_statements
+
+    david = developers(:david)
+
+    assert_equal david, Developer.where(name: "David").last # With Binds
+    assert_operator Developer.count, :>, 0 # Without Binds
+  end
+end
diff --git a/activerecord/test/cases/adapters/postgresql/prepared_statements_test.rb b/activerecord/test/cases/adapters/postgresql/prepared_statements_test.rb
deleted file mode 100644
index f1519db48b..0000000000
--- a/activerecord/test/cases/adapters/postgresql/prepared_statements_test.rb
+++ /dev/null
@@ -1,22 +0,0 @@
-require "cases/helper"
-require "models/developer"
-
-class PreparedStatementsTest < ActiveRecord::PostgreSQLTestCase
-  fixtures :developers
-
-  def setup
-    @default_prepared_statements = Developer.connection_config[:prepared_statements]
-    Developer.connection_config[:prepared_statements] = false
-  end
-
-  def teardown
-    Developer.connection_config[:prepared_statements] = @default_prepared_statements
-  end
-
-  def nothing_raised_with_falsy_prepared_statements
-    assert_nothing_raised do
-      Developer.where(id: 1)
-    end
-  end
-
-end
diff --git a/activerecord/test/cases/adapters/postgresql/quoting_test.rb b/activerecord/test/cases/adapters/postgresql/quoting_test.rb
index 5e6f4dbbb8..d50dc49276 100644
--- a/activerecord/test/cases/adapters/postgresql/quoting_test.rb
+++ b/activerecord/test/cases/adapters/postgresql/quoting_test.rb
@@ -1,5 +1,6 @@
+# frozen_string_literal: true
+
 require "cases/helper"
-require 'ipaddr'
 
 module ActiveRecord
   module ConnectionAdapters
@@ -10,20 +11,20 @@ module ActiveRecord
         end
 
         def test_type_cast_true
-          assert_equal 't', @conn.type_cast(true)
+          assert_equal true, @conn.type_cast(true)
         end
 
         def test_type_cast_false
-          assert_equal 'f', @conn.type_cast(false)
+          assert_equal false, @conn.type_cast(false)
         end
 
         def test_quote_float_nan
-          nan = 0.0/0
+          nan = 0.0 / 0
           assert_equal "'NaN'", @conn.quote(nan)
         end
 
         def test_quote_float_infinity
-          infinity = 1.0/0
+          infinity = 1.0 / 0
           assert_equal "'Infinity'", @conn.quote(infinity)
         end
 
@@ -36,7 +37,7 @@ module ActiveRecord
         def test_quote_bit_string
           value = "'); SELECT * FROM users; /*\n01\n*/--"
           type = OID::Bit.new
-          assert_equal nil, @conn.quote(type.serialize(value))
+          assert_nil @conn.quote(type.serialize(value))
         end
       end
     end
diff --git a/activerecord/test/cases/adapters/postgresql/range_test.rb b/activerecord/test/cases/adapters/postgresql/range_test.rb
index 0edfa4ed9d..813a8721a2 100644
--- a/activerecord/test/cases/adapters/postgresql/range_test.rb
+++ b/activerecord/test/cases/adapters/postgresql/range_test.rb
@@ -1,5 +1,7 @@
+# frozen_string_literal: true
+
 require "cases/helper"
-require 'support/connection_helper'
+require "support/connection_helper"
 
 if ActiveRecord::Base.connection.respond_to?(:supports_ranges?) && ActiveRecord::Base.connection.supports_ranges?
   class PostgresqlRange < ActiveRecord::Base
@@ -23,7 +25,7 @@ if ActiveRecord::Base.connection.respond_to?(:supports_ranges?) && ActiveRecord:
             );
 _SQL
 
-          @connection.create_table('postgresql_ranges') do |t|
+          @connection.create_table("postgresql_ranges") do |t|
             t.daterange :date_range
             t.numrange :num_range
             t.tsrange :ts_range
@@ -32,7 +34,7 @@ _SQL
             t.int8range :int8_range
           end
 
-          @connection.add_column 'postgresql_ranges', 'float_range', 'floatrange'
+          @connection.add_column "postgresql_ranges", "float_range", "floatrange"
         end
         PostgresqlRange.reset_column_information
       rescue ActiveRecord::StatementInvalid
@@ -93,8 +95,8 @@ _SQL
     end
 
     teardown do
-      @connection.drop_table 'postgresql_ranges', if_exists: true
-      @connection.execute 'DROP TYPE IF EXISTS floatrange'
+      @connection.drop_table "postgresql_ranges", if_exists: true
+      @connection.execute "DROP TYPE IF EXISTS floatrange"
       reset_connection
     end
 
@@ -132,10 +134,10 @@ _SQL
     end
 
     def test_numrange_values
-      assert_equal BigDecimal.new('0.1')..BigDecimal.new('0.2'), @first_range.num_range
-      assert_equal BigDecimal.new('0.1')...BigDecimal.new('0.2'), @second_range.num_range
-      assert_equal BigDecimal.new('0.1')...BigDecimal.new('Infinity'), @third_range.num_range
-      assert_equal BigDecimal.new('-Infinity')...BigDecimal.new('Infinity'), @fourth_range.num_range
+      assert_equal BigDecimal("0.1")..BigDecimal("0.2"), @first_range.num_range
+      assert_equal BigDecimal("0.1")...BigDecimal("0.2"), @second_range.num_range
+      assert_equal BigDecimal("0.1")...BigDecimal("Infinity"), @third_range.num_range
+      assert_equal BigDecimal("-Infinity")...BigDecimal("Infinity"), @fourth_range.num_range
       assert_nil @empty_range.num_range
     end
 
@@ -148,8 +150,8 @@ _SQL
     end
 
     def test_tstzrange_values
-      assert_equal Time.parse('2010-01-01 09:30:00 UTC')..Time.parse('2011-01-01 17:30:00 UTC'), @first_range.tstz_range
-      assert_equal Time.parse('2010-01-01 09:30:00 UTC')...Time.parse('2011-01-01 17:30:00 UTC'), @second_range.tstz_range
+      assert_equal Time.parse("2010-01-01 09:30:00 UTC")..Time.parse("2011-01-01 17:30:00 UTC"), @first_range.tstz_range
+      assert_equal Time.parse("2010-01-01 09:30:00 UTC")...Time.parse("2011-01-01 17:30:00 UTC"), @second_range.tstz_range
       assert_equal(-Float::INFINITY...Float::INFINITY, @fourth_range.tstz_range)
       assert_nil @empty_range.tstz_range
     end
@@ -183,17 +185,17 @@ _SQL
     end
 
     def test_create_tstzrange
-      tstzrange = Time.parse('2010-01-01 14:30:00 +0100')...Time.parse('2011-02-02 14:30:00 CDT')
+      tstzrange = Time.parse("2010-01-01 14:30:00 +0100")...Time.parse("2011-02-02 14:30:00 CDT")
       round_trip(@new_range, :tstz_range, tstzrange)
       assert_equal @new_range.tstz_range, tstzrange
-      assert_equal @new_range.tstz_range, Time.parse('2010-01-01 13:30:00 UTC')...Time.parse('2011-02-02 19:30:00 UTC')
+      assert_equal @new_range.tstz_range, Time.parse("2010-01-01 13:30:00 UTC")...Time.parse("2011-02-02 19:30:00 UTC")
     end
 
     def test_update_tstzrange
       assert_equal_round_trip(@first_range, :tstz_range,
-                              Time.parse('2010-01-01 14:30:00 CDT')...Time.parse('2011-02-02 14:30:00 CET'))
+                              Time.parse("2010-01-01 14:30:00 CDT")...Time.parse("2011-02-02 14:30:00 CET"))
       assert_nil_round_trip(@first_range, :tstz_range,
-                            Time.parse('2010-01-01 14:30:00 +0100')...Time.parse('2010-01-01 13:30:00 +0000'))
+                            Time.parse("2010-01-01 14:30:00 +0100")...Time.parse("2010-01-01 13:30:00 +0000"))
     end
 
     def test_create_tsrange
@@ -230,16 +232,67 @@ _SQL
       end
     end
 
+    def test_create_tstzrange_preserve_usec
+      tstzrange = Time.parse("2010-01-01 14:30:00.670277 +0100")...Time.parse("2011-02-02 14:30:00.745125 CDT")
+      round_trip(@new_range, :tstz_range, tstzrange)
+      assert_equal @new_range.tstz_range, tstzrange
+      assert_equal @new_range.tstz_range, Time.parse("2010-01-01 13:30:00.670277 UTC")...Time.parse("2011-02-02 19:30:00.745125 UTC")
+    end
+
+    def test_update_tstzrange_preserve_usec
+      assert_equal_round_trip(@first_range, :tstz_range,
+                              Time.parse("2010-01-01 14:30:00.245124 CDT")...Time.parse("2011-02-02 14:30:00.451274 CET"))
+      assert_nil_round_trip(@first_range, :tstz_range,
+                            Time.parse("2010-01-01 14:30:00.245124 +0100")...Time.parse("2010-01-01 13:30:00.245124 +0000"))
+    end
+
+    def test_create_tsrange_preseve_usec
+      tz = ::ActiveRecord::Base.default_timezone
+      assert_equal_round_trip(@new_range, :ts_range,
+                              Time.send(tz, 2010, 1, 1, 14, 30, 0, 125435)...Time.send(tz, 2011, 2, 2, 14, 30, 0, 225435))
+    end
+
+    def test_update_tsrange_preserve_usec
+      tz = ::ActiveRecord::Base.default_timezone
+      assert_equal_round_trip(@first_range, :ts_range,
+                              Time.send(tz, 2010, 1, 1, 14, 30, 0, 142432)...Time.send(tz, 2011, 2, 2, 14, 30, 0, 224242))
+      assert_nil_round_trip(@first_range, :ts_range,
+                            Time.send(tz, 2010, 1, 1, 14, 30, 0, 142432)...Time.send(tz, 2010, 1, 1, 14, 30, 0, 142432))
+    end
+
+    def test_timezone_awareness_tsrange_preserve_usec
+      tz = "Pacific Time (US & Canada)"
+
+      in_time_zone tz do
+        PostgresqlRange.reset_column_information
+        time_string = "2017-09-26 07:30:59.132451 -0700"
+        time = Time.zone.parse(time_string)
+        assert time.usec > 0
+
+        record = PostgresqlRange.new(ts_range: time_string..time_string)
+        assert_equal time..time, record.ts_range
+        assert_equal ActiveSupport::TimeZone[tz], record.ts_range.begin.time_zone
+        assert_equal time.usec, record.ts_range.begin.usec
+
+        record.save!
+        record.reload
+
+        assert_equal time..time, record.ts_range
+        assert_equal ActiveSupport::TimeZone[tz], record.ts_range.begin.time_zone
+        assert_equal time.usec, record.ts_range.begin.usec
+      end
+    end
+
     def test_create_numrange
       assert_equal_round_trip(@new_range, :num_range,
-                              BigDecimal.new('0.5')...BigDecimal.new('1'))
+                              BigDecimal("0.5")...BigDecimal("1"))
     end
 
     def test_update_numrange
       assert_equal_round_trip(@first_range, :num_range,
-                              BigDecimal.new('0.5')...BigDecimal.new('1'))
+                              BigDecimal("0.5")...BigDecimal("1"))
       assert_nil_round_trip(@first_range, :num_range,
-                            BigDecimal.new('0.5')...BigDecimal.new('0.5'))
+                            BigDecimal("0.5")...BigDecimal("0.5"))
     end
 
     def test_create_daterange
@@ -282,6 +335,12 @@ _SQL
       assert_raises(ArgumentError) { PostgresqlRange.create!(tstz_range: "(''2010-01-01 14:30:00+05'', ''2011-01-01 14:30:00-03'']") }
     end
 
+    def test_where_by_attribute_with_range
+      range = 1..100
+      record = PostgresqlRange.create!(int4_range: range)
+      assert_equal record, PostgresqlRange.where(int4_range: range).take
+    end
+
     def test_update_all_with_ranges
       PostgresqlRange.create!
 
diff --git a/activerecord/test/cases/adapters/postgresql/referential_integrity_test.rb b/activerecord/test/cases/adapters/postgresql/referential_integrity_test.rb
index c895ab9db5..0bcc214c24 100644
--- a/activerecord/test/cases/adapters/postgresql/referential_integrity_test.rb
+++ b/activerecord/test/cases/adapters/postgresql/referential_integrity_test.rb
@@ -1,5 +1,7 @@
-require 'cases/helper'
-require 'support/connection_helper'
+# frozen_string_literal: true
+
+require "cases/helper"
+require "support/connection_helper"
 
 class PostgreSQLReferentialIntegrityTest < ActiveRecord::PostgreSQLTestCase
   self.use_transactional_tests = false
@@ -14,7 +16,7 @@ class PostgreSQLReferentialIntegrityTest < ActiveRecord::PostgreSQLTestCase
     def execute(sql)
       if IS_REFERENTIAL_INTEGRITY_SQL.call(sql)
         super "BROKEN;" rescue nil # put transaction in broken state
-        raise ActiveRecord::StatementInvalid, 'PG::InsufficientPrivilege'
+        raise ActiveRecord::StatementInvalid, "PG::InsufficientPrivilege"
       else
         super
       end
@@ -24,7 +26,7 @@ class PostgreSQLReferentialIntegrityTest < ActiveRecord::PostgreSQLTestCase
   module ProgrammerMistake
     def execute(sql)
       if IS_REFERENTIAL_INTEGRITY_SQL.call(sql)
-        raise ArgumentError, 'something is not right.'
+        raise ArgumentError, "something is not right."
       else
         super
       end
@@ -48,10 +50,10 @@ class PostgreSQLReferentialIntegrityTest < ActiveRecord::PostgreSQLTestCase
     warning = capture(:stderr) do
       e = assert_raises(ActiveRecord::InvalidForeignKey) do
         @connection.disable_referential_integrity do
-          raise ActiveRecord::InvalidForeignKey, 'Should be re-raised'
+          raise ActiveRecord::InvalidForeignKey, "Should be re-raised"
         end
       end
-      assert_equal 'Should be re-raised', e.message
+      assert_equal "Should be re-raised", e.message
     end
     assert_match (/WARNING: Rails was not able to disable referential integrity/), warning
     assert_match (/cause: PG::InsufficientPrivilege/), warning
@@ -63,10 +65,10 @@ class PostgreSQLReferentialIntegrityTest < ActiveRecord::PostgreSQLTestCase
     warning = capture(:stderr) do
       e = assert_raises(ActiveRecord::StatementInvalid) do
         @connection.disable_referential_integrity do
-          raise ActiveRecord::StatementInvalid, 'Should be re-raised'
+          raise ActiveRecord::StatementInvalid, "Should be re-raised"
         end
       end
-      assert_equal 'Should be re-raised', e.message
+      assert_equal "Should be re-raised", e.message
     end
     assert warning.blank?, "expected no warnings but got:\n#{warning}"
   end
@@ -105,7 +107,7 @@ class PostgreSQLReferentialIntegrityTest < ActiveRecord::PostgreSQLTestCase
 
   private
 
-  def assert_transaction_is_not_broken
-    assert_equal 1, @connection.select_value("SELECT 1")
-  end
+    def assert_transaction_is_not_broken
+      assert_equal 1, @connection.select_value("SELECT 1")
+    end
 end
diff --git a/activerecord/test/cases/adapters/postgresql/rename_table_test.rb b/activerecord/test/cases/adapters/postgresql/rename_table_test.rb
index bd64bae308..100d247113 100644
--- a/activerecord/test/cases/adapters/postgresql/rename_table_test.rb
+++ b/activerecord/test/cases/adapters/postgresql/rename_table_test.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require "cases/helper"
 
 class PostgresqlRenameTableTest < ActiveRecord::PostgreSQLTestCase
@@ -24,11 +26,11 @@ class PostgresqlRenameTableTest < ActiveRecord::PostgreSQLTestCase
 
   private
 
-  def num_indices_named(name)
-    @connection.execute(<<-SQL).values.length
-      SELECT 1 FROM "pg_index"
-        JOIN "pg_class" ON "pg_index"."indexrelid" = "pg_class"."oid"
-        WHERE "pg_class"."relname" = '#{name}'
-    SQL
-  end
+    def num_indices_named(name)
+      @connection.execute(<<-SQL).values.length
+        SELECT 1 FROM "pg_index"
+          JOIN "pg_class" ON "pg_index"."indexrelid" = "pg_class"."oid"
+          WHERE "pg_class"."relname" = '#{name}'
+      SQL
+    end
 end
diff --git a/activerecord/test/cases/adapters/postgresql/schema_authorization_test.rb b/activerecord/test/cases/adapters/postgresql/schema_authorization_test.rb
index 285a92f60e..fcb0aec81b 100644
--- a/activerecord/test/cases/adapters/postgresql/schema_authorization_test.rb
+++ b/activerecord/test/cases/adapters/postgresql/schema_authorization_test.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require "cases/helper"
 
 class SchemaThing < ActiveRecord::Base
@@ -6,12 +8,12 @@ end
 class SchemaAuthorizationTest < ActiveRecord::PostgreSQLTestCase
   self.use_transactional_tests = false
 
-  TABLE_NAME = 'schema_things'
+  TABLE_NAME = "schema_things"
   COLUMNS = [
-    'id serial primary key',
-    'name character varying(50)'
+    "id serial primary key",
+    "name character varying(50)"
   ]
-  USERS = ['rails_pg_schema_user1', 'rails_pg_schema_user2']
+  USERS = ["rails_pg_schema_user1", "rails_pg_schema_user2"]
 
   def setup
     @connection = ActiveRecord::Base.connection
@@ -45,7 +47,7 @@ class SchemaAuthorizationTest < ActiveRecord::PostgreSQLTestCase
 
   def test_session_auth=
     assert_raise(ActiveRecord::StatementInvalid) do
-      @connection.session_auth = 'DEFAULT'
+      @connection.session_auth = "DEFAULT"
       @connection.execute "SELECT * FROM #{TABLE_NAME}"
     end
   end
@@ -68,31 +70,20 @@ class SchemaAuthorizationTest < ActiveRecord::PostgreSQLTestCase
         USERS.each do |u|
           @connection.clear_cache!
           set_session_auth u
-          assert_equal u, @connection.select_value("SELECT name FROM #{TABLE_NAME} WHERE id = $1", 'SQL', [bind_param(1)])
+          assert_equal u, @connection.select_value("SELECT name FROM #{TABLE_NAME} WHERE id = $1", "SQL", [bind_param(1)])
           set_session_auth
         end
       end
     end
   end
 
-  def test_schema_uniqueness
-    assert_nothing_raised do
-      set_session_auth
-      USERS.each do |u|
-        set_session_auth u
-        assert_equal u, @connection.select_value("SELECT name FROM #{TABLE_NAME} WHERE id = 1")
-        set_session_auth
-      end
-    end
-  end
-
   def test_sequence_schema_caching
     assert_nothing_raised do
       USERS.each do |u|
         set_session_auth u
-        st = SchemaThing.new :name => 'TEST1'
+        st = SchemaThing.new name: "TEST1"
         st.save!
-        st = SchemaThing.new :id => 5, :name => 'TEST2'
+        st = SchemaThing.new id: 5, name: "TEST2"
         st.save!
         set_session_auth
       end
@@ -100,17 +91,17 @@ class SchemaAuthorizationTest < ActiveRecord::PostgreSQLTestCase
   end
 
   def test_tables_in_current_schemas
-    assert !@connection.tables.include?(TABLE_NAME)
+    assert_not_includes @connection.tables, TABLE_NAME
     USERS.each do |u|
       set_session_auth u
-      assert @connection.tables.include?(TABLE_NAME)
+      assert_includes @connection.tables, TABLE_NAME
       set_session_auth
     end
   end
 
   private
-    def set_session_auth auth = nil
-       @connection.session_auth =  auth || 'default'
+    def set_session_auth(auth = nil)
+      @connection.session_auth = auth || "default"
     end
 
     def bind_param(value)
diff --git a/activerecord/test/cases/adapters/postgresql/schema_test.rb b/activerecord/test/cases/adapters/postgresql/schema_test.rb
index 52ef07f654..2c99fa78bd 100644
--- a/activerecord/test/cases/adapters/postgresql/schema_test.rb
+++ b/activerecord/test/cases/adapters/postgresql/schema_test.rb
@@ -1,6 +1,8 @@
+# frozen_string_literal: true
+
 require "cases/helper"
-require 'models/default'
-require 'support/schema_dumping_helper'
+require "models/default"
+require "support/schema_dumping_helper"
 
 module PGSchemaHelper
   def with_schema_search_path(schema_search_path)
@@ -17,32 +19,32 @@ class SchemaTest < ActiveRecord::PostgreSQLTestCase
   include PGSchemaHelper
   self.use_transactional_tests = false
 
-  SCHEMA_NAME = 'test_schema'
-  SCHEMA2_NAME = 'test_schema2'
-  TABLE_NAME = 'things'
-  CAPITALIZED_TABLE_NAME = 'Things'
-  INDEX_A_NAME = 'a_index_things_on_name'
-  INDEX_B_NAME = 'b_index_things_on_different_columns_in_each_schema'
-  INDEX_C_NAME = 'c_index_full_text_search'
-  INDEX_D_NAME = 'd_index_things_on_description_desc'
-  INDEX_E_NAME = 'e_index_things_on_name_vector'
-  INDEX_A_COLUMN = 'name'
-  INDEX_B_COLUMN_S1 = 'email'
-  INDEX_B_COLUMN_S2 = 'moment'
-  INDEX_C_COLUMN = %q{(to_tsvector('english', coalesce(things.name, '')))}
-  INDEX_D_COLUMN = 'description'
-  INDEX_E_COLUMN = 'name_vector'
+  SCHEMA_NAME = "test_schema"
+  SCHEMA2_NAME = "test_schema2"
+  TABLE_NAME = "things"
+  CAPITALIZED_TABLE_NAME = "Things"
+  INDEX_A_NAME = "a_index_things_on_name"
+  INDEX_B_NAME = "b_index_things_on_different_columns_in_each_schema"
+  INDEX_C_NAME = "c_index_full_text_search"
+  INDEX_D_NAME = "d_index_things_on_description_desc"
+  INDEX_E_NAME = "e_index_things_on_name_vector"
+  INDEX_A_COLUMN = "name"
+  INDEX_B_COLUMN_S1 = "email"
+  INDEX_B_COLUMN_S2 = "moment"
+  INDEX_C_COLUMN = "(to_tsvector('english', coalesce(things.name, '')))"
+  INDEX_D_COLUMN = "description"
+  INDEX_E_COLUMN = "name_vector"
   COLUMNS = [
-    'id integer',
-    'name character varying(50)',
-    'email character varying(50)',
-    'description character varying(100)',
-    'name_vector tsvector',
-    'moment timestamp without time zone default now()'
+    "id integer",
+    "name character varying(50)",
+    "email character varying(50)",
+    "description character varying(100)",
+    "name_vector tsvector",
+    "moment timestamp without time zone default now()"
   ]
-  PK_TABLE_NAME = 'table_with_pk'
-  UNMATCHED_SEQUENCE_NAME = 'unmatched_primary_key_default_value_seq'
-  UNMATCHED_PK_TABLE_NAME = 'table_with_unmatched_sequence_for_pk'
+  PK_TABLE_NAME = "table_with_pk"
+  UNMATCHED_SEQUENCE_NAME = "unmatched_primary_key_default_value_seq"
+  UNMATCHED_PK_TABLE_NAME = "table_with_unmatched_sequence_for_pk"
 
   class Thing1 < ActiveRecord::Base
     self.table_name = "test_schema.things"
@@ -61,7 +63,7 @@ class SchemaTest < ActiveRecord::PostgreSQLTestCase
   end
 
   class Thing5 < ActiveRecord::Base
-    self.table_name = 'things'
+    self.table_name = "things"
   end
 
   class Song < ActiveRecord::Base
@@ -91,6 +93,7 @@ class SchemaTest < ActiveRecord::PostgreSQLTestCase
     @connection.execute "CREATE INDEX #{INDEX_E_NAME} ON #{SCHEMA_NAME}.#{TABLE_NAME}  USING gin (#{INDEX_E_COLUMN});"
     @connection.execute "CREATE INDEX #{INDEX_E_NAME} ON #{SCHEMA2_NAME}.#{TABLE_NAME}  USING gin (#{INDEX_E_COLUMN});"
     @connection.execute "CREATE TABLE #{SCHEMA_NAME}.#{PK_TABLE_NAME} (id serial primary key)"
+    @connection.execute "CREATE TABLE #{SCHEMA2_NAME}.#{PK_TABLE_NAME} (id serial primary key)"
     @connection.execute "CREATE SEQUENCE #{SCHEMA_NAME}.#{UNMATCHED_SEQUENCE_NAME}"
     @connection.execute "CREATE TABLE #{SCHEMA_NAME}.#{UNMATCHED_PK_TABLE_NAME} (id integer NOT NULL DEFAULT nextval('#{SCHEMA_NAME}.#{UNMATCHED_SEQUENCE_NAME}'::regclass), CONSTRAINT unmatched_pkey PRIMARY KEY (id))"
   end
@@ -130,7 +133,7 @@ class SchemaTest < ActiveRecord::PostgreSQLTestCase
     ensure
       @connection.drop_schema "test_schema3"
     end
-    assert !@connection.schema_names.include?("test_schema3")
+    assert_not_includes @connection.schema_names, "test_schema3"
   end
 
   def test_drop_schema_if_exists
@@ -168,21 +171,21 @@ class SchemaTest < ActiveRecord::PostgreSQLTestCase
 
   def test_raise_wrapped_exception_on_bad_prepare
     assert_raises(ActiveRecord::StatementInvalid) do
-      @connection.exec_query "select * from developers where id = ?", 'sql', [bind_param(1)]
+      @connection.exec_query "select * from developers where id = ?", "sql", [bind_param(1)]
     end
   end
 
   if ActiveRecord::Base.connection.prepared_statements
     def test_schema_change_with_prepared_stmt
       altered = false
-      @connection.exec_query "select * from developers where id = $1", 'sql', [bind_param(1)]
-      @connection.exec_query "alter table developers add column zomg int", 'sql', []
+      @connection.exec_query "select * from developers where id = $1", "sql", [bind_param(1)]
+      @connection.exec_query "alter table developers add column zomg int", "sql", []
       altered = true
-      @connection.exec_query "select * from developers where id = $1", 'sql', [bind_param(1)]
+      @connection.exec_query "select * from developers where id = $1", "sql", [bind_param(1)]
     ensure
       # We are not using DROP COLUMN IF EXISTS because that syntax is only
       # supported by pg 9.X
-      @connection.exec_query("alter table developers drop column zomg", 'sql', []) if altered
+      @connection.exec_query("alter table developers drop column zomg", "sql", []) if altered
     end
   end
 
@@ -200,7 +203,7 @@ class SchemaTest < ActiveRecord::PostgreSQLTestCase
   end
 
   def test_data_source_exists_when_not_on_schema_search_path
-    with_schema_search_path('PUBLIC') do
+    with_schema_search_path("PUBLIC") do
       assert(!@connection.data_source_exists?(TABLE_NAME), "data_source exists but should not be found")
     end
   end
@@ -246,9 +249,9 @@ class SchemaTest < ActiveRecord::PostgreSQLTestCase
   end
 
   def test_proper_encoding_of_table_name
-    assert_equal '"table_name"', @connection.quote_table_name('table_name')
+    assert_equal '"table_name"', @connection.quote_table_name("table_name")
     assert_equal '"table.name"', @connection.quote_table_name('"table.name"')
-    assert_equal '"schema_name"."table_name"', @connection.quote_table_name('schema_name.table_name')
+    assert_equal '"schema_name"."table_name"', @connection.quote_table_name("schema_name.table_name")
     assert_equal '"schema_name"."table.name"', @connection.quote_table_name('schema_name."table.name"')
     assert_equal '"schema.name"."table_name"', @connection.quote_table_name('"schema.name".table_name')
     assert_equal '"schema.name"."table.name"', @connection.quote_table_name('"schema.name"."table.name"')
@@ -260,25 +263,25 @@ class SchemaTest < ActiveRecord::PostgreSQLTestCase
     assert_equal 0, Thing3.count
     assert_equal 0, Thing4.count
 
-    Thing1.create(:id => 1, :name => "thing1", :email => "thing1@localhost", :moment => Time.now)
+    Thing1.create(id: 1, name: "thing1", email: "thing1@localhost", moment: Time.now)
     assert_equal 1, Thing1.count
     assert_equal 0, Thing2.count
     assert_equal 0, Thing3.count
     assert_equal 0, Thing4.count
 
-    Thing2.create(:id => 1, :name => "thing1", :email => "thing1@localhost", :moment => Time.now)
+    Thing2.create(id: 1, name: "thing1", email: "thing1@localhost", moment: Time.now)
     assert_equal 1, Thing1.count
     assert_equal 1, Thing2.count
     assert_equal 0, Thing3.count
     assert_equal 0, Thing4.count
 
-    Thing3.create(:id => 1, :name => "thing1", :email => "thing1@localhost", :moment => Time.now)
+    Thing3.create(id: 1, name: "thing1", email: "thing1@localhost", moment: Time.now)
     assert_equal 1, Thing1.count
     assert_equal 1, Thing2.count
     assert_equal 1, Thing3.count
     assert_equal 0, Thing4.count
 
-    Thing4.create(:id => 1, :name => "thing1", :email => "thing1@localhost", :moment => Time.now)
+    Thing4.create(id: 1, name: "thing1", email: "thing1@localhost", moment: Time.now)
     assert_equal 1, Thing1.count
     assert_equal 1, Thing2.count
     assert_equal 1, Thing3.count
@@ -287,7 +290,7 @@ class SchemaTest < ActiveRecord::PostgreSQLTestCase
 
   def test_raise_on_unquoted_schema_name
     assert_raises(ActiveRecord::StatementInvalid) do
-      with_schema_search_path '$user,public'
+      with_schema_search_path "$user,public"
     end
   end
 
@@ -301,13 +304,13 @@ class SchemaTest < ActiveRecord::PostgreSQLTestCase
 
   def test_index_name_exists
     with_schema_search_path(SCHEMA_NAME) do
-      assert @connection.index_name_exists?(TABLE_NAME, INDEX_A_NAME, true)
-      assert @connection.index_name_exists?(TABLE_NAME, INDEX_B_NAME, true)
-      assert @connection.index_name_exists?(TABLE_NAME, INDEX_C_NAME, true)
-      assert @connection.index_name_exists?(TABLE_NAME, INDEX_D_NAME, true)
-      assert @connection.index_name_exists?(TABLE_NAME, INDEX_E_NAME, true)
-      assert @connection.index_name_exists?(TABLE_NAME, INDEX_E_NAME, true)
-      assert_not @connection.index_name_exists?(TABLE_NAME, 'missing_index', true)
+      assert @connection.index_name_exists?(TABLE_NAME, INDEX_A_NAME)
+      assert @connection.index_name_exists?(TABLE_NAME, INDEX_B_NAME)
+      assert @connection.index_name_exists?(TABLE_NAME, INDEX_C_NAME)
+      assert @connection.index_name_exists?(TABLE_NAME, INDEX_D_NAME)
+      assert @connection.index_name_exists?(TABLE_NAME, INDEX_E_NAME)
+      assert @connection.index_name_exists?(TABLE_NAME, INDEX_E_NAME)
+      assert_not @connection.index_name_exists?(TABLE_NAME, "missing_index")
     end
   end
 
@@ -332,7 +335,7 @@ class SchemaTest < ActiveRecord::PostgreSQLTestCase
     @connection.execute "CREATE INDEX \"things_Index\" ON #{SCHEMA_NAME}.things (name)"
 
     with_schema_search_path SCHEMA_NAME do
-      assert_nothing_raised { @connection.remove_index "things", name: "things_Index"}
+      assert_nothing_raised { @connection.remove_index "things", name: "things_Index" }
     end
   end
 
@@ -356,21 +359,13 @@ class SchemaTest < ActiveRecord::PostgreSQLTestCase
       %(#{SCHEMA_NAME}."#{PK_TABLE_NAME}"),
       %(#{SCHEMA_NAME}.#{PK_TABLE_NAME})
     ].each do |given|
-      assert_equal 'id', @connection.primary_key(given), "primary key should be found when table referenced as #{given}"
+      assert_equal "id", @connection.primary_key(given), "primary key should be found when table referenced as #{given}"
     end
   end
 
   def test_primary_key_assuming_schema_search_path
-    with_schema_search_path(SCHEMA_NAME) do
-      assert_equal 'id', @connection.primary_key(PK_TABLE_NAME), "primary key should be found"
-    end
-  end
-
-  def test_primary_key_raises_error_if_table_not_found_on_schema_search_path
-    with_schema_search_path(SCHEMA2_NAME) do
-      assert_raises(ActiveRecord::StatementInvalid) do
-        @connection.primary_key(PK_TABLE_NAME)
-      end
+    with_schema_search_path("#{SCHEMA_NAME}, #{SCHEMA2_NAME}") do
+      assert_equal "id", @connection.primary_key(PK_TABLE_NAME), "primary key should be found"
     end
   end
 
@@ -381,19 +376,19 @@ class SchemaTest < ActiveRecord::PostgreSQLTestCase
       %("#{SCHEMA_NAME}"."#{UNMATCHED_PK_TABLE_NAME}")
     ].each do |given|
       pk, seq = @connection.pk_and_sequence_for(given)
-      assert_equal 'id', pk, "primary key should be found when table referenced as #{given}"
+      assert_equal "id", pk, "primary key should be found when table referenced as #{given}"
       assert_equal pg_name.new(SCHEMA_NAME, "#{PK_TABLE_NAME}_id_seq"), seq, "sequence name should be found when table referenced as #{given}" if given == %("#{SCHEMA_NAME}"."#{PK_TABLE_NAME}")
-      assert_equal pg_name.new(SCHEMA_NAME, UNMATCHED_SEQUENCE_NAME), seq, "sequence name should be found when table referenced as #{given}" if given ==  %("#{SCHEMA_NAME}"."#{UNMATCHED_PK_TABLE_NAME}")
+      assert_equal pg_name.new(SCHEMA_NAME, UNMATCHED_SEQUENCE_NAME), seq, "sequence name should be found when table referenced as #{given}" if given == %("#{SCHEMA_NAME}"."#{UNMATCHED_PK_TABLE_NAME}")
     end
   end
 
   def test_current_schema
     {
-      %('$user',public)                        => 'public',
+      %('$user',public)                        => "public",
       SCHEMA_NAME                              => SCHEMA_NAME,
       %(#{SCHEMA2_NAME},#{SCHEMA_NAME},public) => SCHEMA2_NAME,
-      %(public,#{SCHEMA2_NAME},#{SCHEMA_NAME}) => 'public'
-    }.each do |given,expect|
+      %(public,#{SCHEMA2_NAME},#{SCHEMA_NAME}) => "public"
+    }.each do |given, expect|
       with_schema_search_path(given) { assert_equal expect, @connection.current_schema }
     end
   end
@@ -401,7 +396,7 @@ class SchemaTest < ActiveRecord::PostgreSQLTestCase
   def test_prepared_statements_with_multiple_schemas
     [SCHEMA_NAME, SCHEMA2_NAME].each do |schema_name|
       with_schema_search_path schema_name do
-        Thing5.create(:id => 1, :name => "thing inside #{SCHEMA_NAME}", :email => "thing1@localhost", :moment => Time.now)
+        Thing5.create(id: 1, name: "thing inside #{SCHEMA_NAME}", email: "thing1@localhost", moment: Time.now)
       end
     end
 
@@ -414,11 +409,11 @@ class SchemaTest < ActiveRecord::PostgreSQLTestCase
 
   def test_schema_exists?
     {
-      'public'     => true,
+      "public"     => true,
       SCHEMA_NAME  => true,
       SCHEMA2_NAME => true,
-      'darkside'   => false
-    }.each do |given,expect|
+      "darkside"   => false
+    }.each do |given, expect|
       assert_equal expect, @connection.schema_exists?(given)
     end
   end
@@ -442,7 +437,7 @@ class SchemaTest < ActiveRecord::PostgreSQLTestCase
   private
     def columns(table_name)
       @connection.send(:column_definitions, table_name).map do |name, type, default|
-        "#{name} #{type}" + (default ? " default #{default}" : '')
+        "#{name} #{type}" + (default ? " default #{default}" : "")
       end
     end
 
@@ -464,7 +459,7 @@ class SchemaTest < ActiveRecord::PostgreSQLTestCase
         assert_equal :btree, index_d.using
         assert_equal :gin,   index_e.using
 
-        assert_equal :desc,  index_d.orders[INDEX_D_COLUMN]
+        assert_equal :desc,  index_d.orders
       end
     end
 
@@ -505,6 +500,38 @@ class SchemaForeignKeyTest < ActiveRecord::PostgreSQLTestCase
   end
 end
 
+class SchemaIndexOpclassTest < ActiveRecord::PostgreSQLTestCase
+  include SchemaDumpingHelper
+
+  setup do
+    @connection = ActiveRecord::Base.connection
+    @connection.create_table "trains" do |t|
+      t.string :name
+      t.text :description
+    end
+  end
+
+  teardown do
+    @connection.drop_table "trains", if_exists: true
+  end
+
+  def test_string_opclass_is_dumped
+    @connection.execute "CREATE INDEX trains_name_and_description ON trains USING btree(name text_pattern_ops, description text_pattern_ops)"
+
+    output = dump_table_schema "trains"
+
+    assert_match(/opclass: :text_pattern_ops/, output)
+  end
+
+  def test_non_default_opclass_is_dumped
+    @connection.execute "CREATE INDEX trains_name_and_description ON trains USING btree(name, description text_pattern_ops)"
+
+    output = dump_table_schema "trains"
+
+    assert_match(/opclass: \{ description: :text_pattern_ops \}/, output)
+  end
+end
+
 class DefaultsUsingMultipleSchemasAndDomainTest < ActiveRecord::PostgreSQLTestCase
   setup do
     @connection = ActiveRecord::Base.connection
@@ -539,7 +566,7 @@ class DefaultsUsingMultipleSchemasAndDomainTest < ActiveRecord::PostgreSQLTestCa
   end
 
   def test_decimal_defaults_in_new_schema_when_overriding_domain
-    assert_equal BigDecimal.new("3.14159265358979323846"), Default.new.decimal_col, "Default of decimal column was not correctly parsed"
+    assert_equal BigDecimal("3.14159265358979323846"), Default.new.decimal_col, "Default of decimal column was not correctly parsed"
   end
 
   def test_bpchar_defaults_in_new_schema_when_overriding_domain
diff --git a/activerecord/test/cases/adapters/postgresql/serial_test.rb b/activerecord/test/cases/adapters/postgresql/serial_test.rb
index 8abe064bf1..6a99323be5 100644
--- a/activerecord/test/cases/adapters/postgresql/serial_test.rb
+++ b/activerecord/test/cases/adapters/postgresql/serial_test.rb
@@ -1,5 +1,7 @@
+# frozen_string_literal: true
+
 require "cases/helper"
-require 'support/schema_dumping_helper'
+require "support/schema_dumping_helper"
 
 class PostgresqlSerialTest < ActiveRecord::PostgreSQLTestCase
   include SchemaDumpingHelper
@@ -84,3 +86,71 @@ class PostgresqlBigSerialTest < ActiveRecord::PostgreSQLTestCase
     assert_match %r{t\.bigint\s+"serials_id",\s+default: -> \{ "nextval\('postgresql_big_serials_id_seq'::regclass\)" \}$}, output
   end
 end
+
+module SequenceNameDetectionTestCases
+  class CollidedSequenceNameTest < ActiveRecord::PostgreSQLTestCase
+    include SchemaDumpingHelper
+
+    def setup
+      @connection = ActiveRecord::Base.connection
+      @connection.create_table :foo_bar, force: true do |t|
+        t.serial :baz_id
+      end
+      @connection.create_table :foo, force: true do |t|
+        t.serial :bar_id
+        t.bigserial :bar_baz_id
+      end
+    end
+
+    def teardown
+      @connection.drop_table :foo_bar, if_exists: true
+      @connection.drop_table :foo, if_exists: true
+    end
+
+    def test_serial_columns
+      columns = @connection.columns(:foo)
+      columns.each do |column|
+        assert_equal :integer, column.type
+        assert column.serial?
+      end
+    end
+
+    def test_schema_dump_with_collided_sequence_name
+      output = dump_table_schema "foo"
+      assert_match %r{t\.serial\s+"bar_id",\s+null: false$}, output
+      assert_match %r{t\.bigserial\s+"bar_baz_id",\s+null: false$}, output
+    end
+  end
+
+  class LongerSequenceNameDetectionTest < ActiveRecord::PostgreSQLTestCase
+    include SchemaDumpingHelper
+
+    def setup
+      @table_name = "long_table_name_to_test_sequence_name_detection_for_serial_cols"
+      @connection = ActiveRecord::Base.connection
+      @connection.create_table @table_name, force: true do |t|
+        t.serial :seq
+        t.bigserial :bigseq
+      end
+    end
+
+    def teardown
+      @connection.drop_table @table_name, if_exists: true
+    end
+
+    def test_serial_columns
+      columns = @connection.columns(@table_name)
+      columns.each do |column|
+        assert_equal :integer, column.type
+        assert column.serial?
+      end
+    end
+
+    def test_schema_dump_with_long_table_name
+      output = dump_table_schema @table_name
+      assert_match %r{create_table "#{@table_name}", force: :cascade}, output
+      assert_match %r{t\.serial\s+"seq",\s+null: false$}, output
+      assert_match %r{t\.bigserial\s+"bigseq",\s+null: false$}, output
+    end
+  end
+end
diff --git a/activerecord/test/cases/adapters/postgresql/statement_pool_test.rb b/activerecord/test/cases/adapters/postgresql/statement_pool_test.rb
index 5aab246c99..fef4b02b04 100644
--- a/activerecord/test/cases/adapters/postgresql/statement_pool_test.rb
+++ b/activerecord/test/cases/adapters/postgresql/statement_pool_test.rb
@@ -1,15 +1,17 @@
-require 'cases/helper'
+# frozen_string_literal: true
+
+require "cases/helper"
 
 module ActiveRecord
   module ConnectionAdapters
     class PostgreSQLAdapter < AbstractAdapter
-      class InactivePGconn
+      class InactivePgConnection
         def query(*args)
-          raise PGError
+          raise PG::Error
         end
 
         def status
-          PGconn::CONNECTION_BAD
+          PG::CONNECTION_BAD
         end
       end
 
@@ -17,22 +19,22 @@ module ActiveRecord
         if Process.respond_to?(:fork)
           def test_cache_is_per_pid
             cache = StatementPool.new nil, 10
-            cache['foo'] = 'bar'
-            assert_equal 'bar', cache['foo']
+            cache["foo"] = "bar"
+            assert_equal "bar", cache["foo"]
 
             pid = fork {
-              lookup = cache['foo'];
+              lookup = cache["foo"]
               exit!(!lookup)
             }
 
             Process.waitpid pid
-            assert $?.success?, 'process should exit successfully'
+            assert $?.success?, "process should exit successfully"
           end
         end
 
         def test_dealloc_does_not_raise_on_inactive_connection
-          cache = StatementPool.new InactivePGconn.new, 10
-          cache['foo'] = 'bar'
+          cache = StatementPool.new InactivePgConnection.new, 10
+          cache["foo"] = "bar"
           assert_nothing_raised { cache.clear }
         end
       end
diff --git a/activerecord/test/cases/adapters/postgresql/timestamp_test.rb b/activerecord/test/cases/adapters/postgresql/timestamp_test.rb
index 4c4866b46b..b7f213efc8 100644
--- a/activerecord/test/cases/adapters/postgresql/timestamp_test.rb
+++ b/activerecord/test/cases/adapters/postgresql/timestamp_test.rb
@@ -1,6 +1,8 @@
-require 'cases/helper'
-require 'models/developer'
-require 'models/topic'
+# frozen_string_literal: true
+
+require "cases/helper"
+require "models/developer"
+require "models/topic"
 
 class PostgresqlTimestampTest < ActiveRecord::PostgreSQLTestCase
   class PostgresqlTimestampWithZone < ActiveRecord::Base; end
@@ -21,7 +23,7 @@ class PostgresqlTimestampTest < ActiveRecord::PostgreSQLTestCase
       @connection.reconnect!
 
       timestamp = PostgresqlTimestampWithZone.find(1)
-      assert_equal Time.utc(2010,1,1, 11,0,0), timestamp.time
+      assert_equal Time.utc(2010, 1, 1, 11, 0, 0), timestamp.time
       assert_instance_of Time, timestamp.time
     end
   ensure
@@ -32,10 +34,10 @@ class PostgresqlTimestampTest < ActiveRecord::PostgreSQLTestCase
     with_timezone_config default: :local, aware_attributes: false do
       @connection.reconnect!
       # make sure to use a non-UTC time zone
-      @connection.execute("SET time zone 'America/Jamaica'", 'SCHEMA')
+      @connection.execute("SET time zone 'America/Jamaica'", "SCHEMA")
 
       timestamp = PostgresqlTimestampWithZone.find(1)
-      assert_equal Time.utc(2010,1,1, 11,0,0), timestamp.time
+      assert_equal Time.utc(2010, 1, 1, 11, 0, 0), timestamp.time
       assert_instance_of Time, timestamp.time
     end
   ensure
@@ -54,37 +56,37 @@ class PostgresqlTimestampFixtureTest < ActiveRecord::PostgreSQLTestCase
 
   def test_load_infinity_and_beyond
     d = Developer.find_by_sql("select 'infinity'::timestamp as updated_at")
-    assert d.first.updated_at.infinite?, 'timestamp should be infinite'
+    assert d.first.updated_at.infinite?, "timestamp should be infinite"
 
     d = Developer.find_by_sql("select '-infinity'::timestamp as updated_at")
     time = d.first.updated_at
-    assert time.infinite?, 'timestamp should be infinite'
+    assert time.infinite?, "timestamp should be infinite"
     assert_operator time, :<, 0
   end
 
   def test_save_infinity_and_beyond
-    d = Developer.create!(:name => 'aaron', :updated_at => 1.0 / 0.0)
+    d = Developer.create!(name: "aaron", updated_at: 1.0 / 0.0)
     assert_equal(1.0 / 0.0, d.updated_at)
 
-    d = Developer.create!(:name => 'aaron', :updated_at => -1.0 / 0.0)
+    d = Developer.create!(name: "aaron", updated_at: -1.0 / 0.0)
     assert_equal(-1.0 / 0.0, d.updated_at)
   end
 
   def test_bc_timestamp
     date = Date.new(0) - 1.week
-    Developer.create!(:name => "aaron", :updated_at => date)
+    Developer.create!(name: "aaron", updated_at: date)
     assert_equal date, Developer.find_by_name("aaron").updated_at
   end
 
   def test_bc_timestamp_leap_year
     date = Time.utc(-4, 2, 29)
-    Developer.create!(:name => "taihou", :updated_at => date)
+    Developer.create!(name: "taihou", updated_at: date)
     assert_equal date, Developer.find_by_name("taihou").updated_at
   end
 
   def test_bc_timestamp_year_zero
     date = Time.utc(0, 4, 7)
-    Developer.create!(:name => "yahagi", :updated_at => date)
+    Developer.create!(name: "yahagi", updated_at: date)
     assert_equal date, Developer.find_by_name("yahagi").updated_at
   end
 end
diff --git a/activerecord/test/cases/adapters/postgresql/transaction_test.rb b/activerecord/test/cases/adapters/postgresql/transaction_test.rb
index e76705a802..9821b103df 100644
--- a/activerecord/test/cases/adapters/postgresql/transaction_test.rb
+++ b/activerecord/test/cases/adapters/postgresql/transaction_test.rb
@@ -1,21 +1,27 @@
+# frozen_string_literal: true
+
 require "cases/helper"
-require 'support/connection_helper'
+require "support/connection_helper"
+require "concurrent/atomic/cyclic_barrier"
 
 module ActiveRecord
   class PostgresqlTransactionTest < ActiveRecord::PostgreSQLTestCase
     self.use_transactional_tests = false
 
     class Sample < ActiveRecord::Base
-      self.table_name = 'samples'
+      self.table_name = "samples"
     end
 
     setup do
+      @abort, Thread.abort_on_exception = Thread.abort_on_exception, false
+      Thread.report_on_exception, @original_report_on_exception = false, Thread.report_on_exception if Thread.respond_to?(:report_on_exception)
+
       @connection = ActiveRecord::Base.connection
 
       @connection.transaction do
-        @connection.drop_table 'samples', if_exists: true
-        @connection.create_table('samples') do |t|
-          t.integer 'value'
+        @connection.drop_table "samples", if_exists: true
+        @connection.create_table("samples") do |t|
+          t.integer "value"
         end
       end
 
@@ -23,50 +29,162 @@ module ActiveRecord
     end
 
     teardown do
-      @connection.drop_table 'samples', if_exists: true
+      @connection.drop_table "samples", if_exists: true
+
+      Thread.abort_on_exception = @abort
+      Thread.report_on_exception = @original_report_on_exception if Thread.respond_to?(:report_on_exception)
     end
 
-    test "raises error when a serialization failure occurs" do
-      with_warning_suppression do
-        assert_raises(ActiveRecord::TransactionSerializationError) do
-          thread = Thread.new do
-            Sample.transaction isolation: :serializable do
-              Sample.delete_all
+    test "raises SerializationFailure when a serialization failure occurs" do
+      assert_raises(ActiveRecord::SerializationFailure) do
+        before = Concurrent::CyclicBarrier.new(2)
+        after = Concurrent::CyclicBarrier.new(2)
 
-              10.times do |i|
-                sleep 0.1
+        thread = Thread.new do
+          with_warning_suppression do
+            Sample.transaction isolation: :serializable do
+              before.wait
+              Sample.create value: Sample.sum(:value)
+              after.wait
+            end
+          end
+        end
 
-                Sample.create value: i
-              end
+        begin
+          with_warning_suppression do
+            Sample.transaction isolation: :serializable do
+              before.wait
+              Sample.create value: Sample.sum(:value)
+              after.wait
             end
           end
+        ensure
+          thread.join
+        end
+      end
+    end
 
-          sleep 0.1
+    test "raises Deadlocked when a deadlock is encountered" do
+      with_warning_suppression do
+        assert_raises(ActiveRecord::Deadlocked) do
+          barrier = Concurrent::CyclicBarrier.new(2)
 
-          Sample.transaction isolation: :serializable do
-            Sample.delete_all
+          s1 = Sample.create value: 1
+          s2 = Sample.create value: 2
 
-            10.times do |i|
-              sleep 0.1
+          thread = Thread.new do
+            Sample.transaction do
+              s1.lock!
+              barrier.wait
+              s2.update_attributes value: 1
+            end
+          end
 
-              Sample.create value: i
+          begin
+            Sample.transaction do
+              s2.lock!
+              barrier.wait
+              s1.update_attributes value: 2
             end
+          ensure
+            thread.join
+          end
+        end
+      end
+    end
 
-            sleep 1
+    test "raises LockWaitTimeout when lock wait timeout exceeded" do
+      skip unless ActiveRecord::Base.connection.postgresql_version >= 90300
+      assert_raises(ActiveRecord::LockWaitTimeout) do
+        s = Sample.create!(value: 1)
+        latch1 = Concurrent::CountDownLatch.new
+        latch2 = Concurrent::CountDownLatch.new
+
+        thread = Thread.new do
+          Sample.transaction do
+            Sample.lock.find(s.id)
+            latch1.count_down
+            latch2.wait
           end
+        end
 
+        begin
+          Sample.transaction do
+            latch1.wait
+            Sample.connection.execute("SET lock_timeout = 1")
+            Sample.lock.find(s.id)
+          end
+        ensure
+          Sample.connection.execute("SET lock_timeout = DEFAULT")
+          latch2.count_down
           thread.join
         end
       end
     end
 
-    protected
+    test "raises QueryCanceled when statement timeout exceeded" do
+      assert_raises(ActiveRecord::QueryCanceled) do
+        s = Sample.create!(value: 1)
+        latch1 = Concurrent::CountDownLatch.new
+        latch2 = Concurrent::CountDownLatch.new
+
+        thread = Thread.new do
+          Sample.transaction do
+            Sample.lock.find(s.id)
+            latch1.count_down
+            latch2.wait
+          end
+        end
 
-    def with_warning_suppression
-      log_level = @connection.client_min_messages
-      @connection.client_min_messages = 'error'
-      yield
-      @connection.client_min_messages = log_level
+        begin
+          Sample.transaction do
+            latch1.wait
+            Sample.connection.execute("SET statement_timeout = 1")
+            Sample.lock.find(s.id)
+          end
+        ensure
+          Sample.connection.execute("SET statement_timeout = DEFAULT")
+          latch2.count_down
+          thread.join
+        end
+      end
     end
+
+    test "raises QueryCanceled when canceling statement due to user request" do
+      assert_raises(ActiveRecord::QueryCanceled) do
+        s = Sample.create!(value: 1)
+        latch = Concurrent::CountDownLatch.new
+
+        thread = Thread.new do
+          Sample.transaction do
+            Sample.lock.find(s.id)
+            latch.count_down
+            sleep(0.5)
+            conn = Sample.connection
+            pid = conn.query_value("SELECT pid FROM pg_stat_activity WHERE query LIKE '% FOR UPDATE'")
+            conn.execute("SELECT pg_cancel_backend(#{pid})")
+          end
+        end
+
+        begin
+          Sample.transaction do
+            latch.wait
+            Sample.lock.find(s.id)
+          end
+        ensure
+          thread.join
+        end
+      end
+    end
+
+    private
+
+      def with_warning_suppression
+        log_level = ActiveRecord::Base.connection.client_min_messages
+        ActiveRecord::Base.connection.client_min_messages = "error"
+        yield
+      ensure
+        ActiveRecord::Base.connection.client_min_messages = log_level
+      end
   end
 end
diff --git a/activerecord/test/cases/adapters/postgresql/type_lookup_test.rb b/activerecord/test/cases/adapters/postgresql/type_lookup_test.rb
index ea0f0b8fa5..8212ed4263 100644
--- a/activerecord/test/cases/adapters/postgresql/type_lookup_test.rb
+++ b/activerecord/test/cases/adapters/postgresql/type_lookup_test.rb
@@ -1,4 +1,6 @@
-require 'cases/helper'
+# frozen_string_literal: true
+
+require "cases/helper"
 
 class PostgresqlTypeLookupTest < ActiveRecord::PostgreSQLTestCase
   setup do
@@ -6,28 +8,28 @@ class PostgresqlTypeLookupTest < ActiveRecord::PostgreSQLTestCase
   end
 
   test "array delimiters are looked up correctly" do
-    box_array = @connection.type_map.lookup(1020)
-    int_array = @connection.type_map.lookup(1007)
+    box_array = @connection.send(:type_map).lookup(1020)
+    int_array = @connection.send(:type_map).lookup(1007)
 
-    assert_equal ';', box_array.delimiter
-    assert_equal ',', int_array.delimiter
+    assert_equal ";", box_array.delimiter
+    assert_equal ",", int_array.delimiter
   end
 
   test "array types correctly respect registration of subtypes" do
-    int_array = @connection.type_map.lookup(1007, -1, "integer[]")
-    bigint_array = @connection.type_map.lookup(1016, -1, "bigint[]")
+    int_array = @connection.send(:type_map).lookup(1007, -1, "integer[]")
+    bigint_array = @connection.send(:type_map).lookup(1016, -1, "bigint[]")
     big_array = [123456789123456789]
 
     assert_raises(ActiveModel::RangeError) { int_array.serialize(big_array) }
-    assert_equal "{123456789123456789}", bigint_array.serialize(big_array)
+    assert_equal "{123456789123456789}", @connection.type_cast(bigint_array.serialize(big_array))
   end
 
   test "range types correctly respect registration of subtypes" do
-    int_range = @connection.type_map.lookup(3904, -1, "int4range")
-    bigint_range = @connection.type_map.lookup(3926, -1, "int8range")
+    int_range = @connection.send(:type_map).lookup(3904, -1, "int4range")
+    bigint_range = @connection.send(:type_map).lookup(3926, -1, "int8range")
     big_range = 0..123456789123456789
 
     assert_raises(ActiveModel::RangeError) { int_range.serialize(big_range) }
-    assert_equal "[0,123456789123456789]", bigint_range.serialize(big_range)
+    assert_equal "[0,123456789123456789]", @connection.type_cast(bigint_range.serialize(big_range))
   end
 end
diff --git a/activerecord/test/cases/adapters/postgresql/utils_test.rb b/activerecord/test/cases/adapters/postgresql/utils_test.rb
index 095c1826e5..c91884f384 100644
--- a/activerecord/test/cases/adapters/postgresql/utils_test.rb
+++ b/activerecord/test/cases/adapters/postgresql/utils_test.rb
@@ -1,5 +1,7 @@
-require 'cases/helper'
-require 'active_record/connection_adapters/postgresql/utils'
+# frozen_string_literal: true
+
+require "cases/helper"
+require "active_record/connection_adapters/postgresql/utils"
 
 class PostgreSQLUtilsTest < ActiveRecord::PostgreSQLTestCase
   Name = ActiveRecord::ConnectionAdapters::PostgreSQL::Name
@@ -7,14 +9,14 @@ class PostgreSQLUtilsTest < ActiveRecord::PostgreSQLTestCase
 
   def test_extract_schema_qualified_name
     {
-      %(table_name)            => [nil,'table_name'],
-      %("table.name")          => [nil,'table.name'],
+      %(table_name)            => [nil, "table_name"],
+      %("table.name")          => [nil, "table.name"],
       %(schema.table_name)     => %w{schema table_name},
       %("schema".table_name)   => %w{schema table_name},
       %(schema."table_name")   => %w{schema table_name},
       %("schema"."table_name") => %w{schema table_name},
-      %("even spaces".table)   => ['even spaces','table'],
-      %(schema."table.name")   => ['schema', 'table.name']
+      %("even spaces".table)   => ["even spaces", "table"],
+      %(schema."table.name")   => ["schema", "table.name"]
     }.each do |given, expect|
       assert_equal Name.new(*expect), extract_schema_qualified_name(given)
     end
@@ -54,9 +56,9 @@ class PostgreSQLNameTest < ActiveRecord::PostgreSQLTestCase
   end
 
   test "can be used as hash key" do
-    hash = {Name.new("schema", "article_seq") => "success"}
+    hash = { Name.new("schema", "article_seq") => "success" }
     assert_equal "success", hash[Name.new("schema", "article_seq")]
-    assert_equal nil, hash[Name.new("schema", "articles")]
-    assert_equal nil, hash[Name.new("public", "article_seq")]
+    assert_nil hash[Name.new("schema", "articles")]
+    assert_nil hash[Name.new("public", "article_seq")]
   end
 end
diff --git a/activerecord/test/cases/adapters/postgresql/uuid_test.rb b/activerecord/test/cases/adapters/postgresql/uuid_test.rb
index 7628075ad2..c24e0cb330 100644
--- a/activerecord/test/cases/adapters/postgresql/uuid_test.rb
+++ b/activerecord/test/cases/adapters/postgresql/uuid_test.rb
@@ -1,5 +1,7 @@
+# frozen_string_literal: true
+
 require "cases/helper"
-require 'support/schema_dumping_helper'
+require "support/schema_dumping_helper"
 
 module PostgresqlUUIDHelper
   def connection
@@ -9,6 +11,14 @@ module PostgresqlUUIDHelper
   def drop_table(name)
     connection.drop_table name, if_exists: true
   end
+
+  def uuid_function
+    connection.supports_pgcrypto_uuid? ? "gen_random_uuid()" : "uuid_generate_v4()"
+  end
+
+  def uuid_default
+    connection.supports_pgcrypto_uuid? ? {} : { default: uuid_function }
+  end
 end
 
 class PostgresqlUUIDTest < ActiveRecord::PostgreSQLTestCase
@@ -20,10 +30,11 @@ class PostgresqlUUIDTest < ActiveRecord::PostgreSQLTestCase
   end
 
   setup do
-    enable_extension!('uuid-ossp', connection)
+    enable_extension!("uuid-ossp", connection)
+    enable_extension!("pgcrypto",  connection) if connection.supports_pgcrypto_uuid?
 
     connection.create_table "uuid_data_type" do |t|
-      t.uuid 'guid'
+      t.uuid "guid"
     end
   end
 
@@ -31,21 +42,53 @@ class PostgresqlUUIDTest < ActiveRecord::PostgreSQLTestCase
     drop_table "uuid_data_type"
   end
 
+  if ActiveRecord::Base.connection.respond_to?(:supports_pgcrypto_uuid?) &&
+      ActiveRecord::Base.connection.supports_pgcrypto_uuid?
+    def test_uuid_column_default
+      connection.add_column :uuid_data_type, :thingy, :uuid, null: false, default: "gen_random_uuid()"
+      UUIDType.reset_column_information
+      column = UUIDType.columns_hash["thingy"]
+      assert_equal "gen_random_uuid()", column.default_function
+    end
+  end
+
   def test_change_column_default
-    @connection.add_column :uuid_data_type, :thingy, :uuid, null: false, default: "uuid_generate_v1()"
+    connection.add_column :uuid_data_type, :thingy, :uuid, null: false, default: "uuid_generate_v1()"
     UUIDType.reset_column_information
-    column = UUIDType.columns_hash['thingy']
+    column = UUIDType.columns_hash["thingy"]
     assert_equal "uuid_generate_v1()", column.default_function
 
-    @connection.change_column :uuid_data_type, :thingy, :uuid, null: false, default: "uuid_generate_v4()"
-
+    connection.change_column :uuid_data_type, :thingy, :uuid, null: false, default: "uuid_generate_v4()"
     UUIDType.reset_column_information
-    column = UUIDType.columns_hash['thingy']
+    column = UUIDType.columns_hash["thingy"]
     assert_equal "uuid_generate_v4()", column.default_function
   ensure
     UUIDType.reset_column_information
   end
 
+  def test_add_column_with_null_true_and_default_nil
+    connection.add_column :uuid_data_type, :thingy, :uuid, null: true, default: nil
+
+    UUIDType.reset_column_information
+    column = UUIDType.columns_hash["thingy"]
+
+    assert column.null
+    assert_nil column.default
+  end
+
+  def test_add_column_with_default_array
+    connection.add_column :uuid_data_type, :thingy, :uuid, array: true, default: []
+
+    UUIDType.reset_column_information
+    column = UUIDType.columns_hash["thingy"]
+
+    assert column.array?
+    assert_equal "{}", column.default
+
+    schema = dump_table_schema "uuid_data_type"
+    assert_match %r{t\.uuid "thingy", default: \[\], array: true$}, schema
+  end
+
   def test_data_type_of_uuid_types
     column = UUIDType.columns_hash["guid"]
     assert_equal :uuid, column.type
@@ -57,46 +100,48 @@ class PostgresqlUUIDTest < ActiveRecord::PostgreSQLTestCase
   end
 
   def test_treat_blank_uuid_as_nil
-    UUIDType.create! guid: ''
-    assert_equal(nil, UUIDType.last.guid)
+    UUIDType.create! guid: ""
+    assert_nil(UUIDType.last.guid)
   end
 
   def test_treat_invalid_uuid_as_nil
-    uuid = UUIDType.create! guid: 'foobar'
-    assert_equal(nil, uuid.guid)
+    uuid = UUIDType.create! guid: "foobar"
+    assert_nil(uuid.guid)
   end
 
   def test_invalid_uuid_dont_modify_before_type_cast
-    uuid = UUIDType.new guid: 'foobar'
-    assert_equal 'foobar', uuid.guid_before_type_cast
+    uuid = UUIDType.new guid: "foobar"
+    assert_equal "foobar", uuid.guid_before_type_cast
   end
 
   def test_acceptable_uuid_regex
     # Valid uuids
-    ['A0EEBC99-9C0B-4EF8-BB6D-6BB9BD380A11',
-     '{a0eebc99-9c0b-4ef8-bb6d-6bb9bd380a11}',
-     'a0eebc999c0b4ef8bb6d6bb9bd380a11',
-     'a0ee-bc99-9c0b-4ef8-bb6d-6bb9-bd38-0a11',
-     '{a0eebc99-9c0b4ef8-bb6d6bb9-bd380a11}',
+    ["A0EEBC99-9C0B-4EF8-BB6D-6BB9BD380A11",
+     "{a0eebc99-9c0b-4ef8-bb6d-6bb9bd380a11}",
+     "a0eebc999c0b4ef8bb6d6bb9bd380a11",
+     "a0ee-bc99-9c0b-4ef8-bb6d-6bb9-bd38-0a11",
+     "{a0eebc99-9c0b4ef8-bb6d6bb9-bd380a11}",
      # The following is not a valid RFC 4122 UUID, but PG doesn't seem to care,
      # so we shouldn't block it either. (Pay attention to "fb6d" – the "f" here
      # is invalid – it must be one of 8, 9, A, B, a, b according to the spec.)
-     '{a0eebc99-9c0b-4ef8-fb6d-6bb9bd380a11}',
+     "{a0eebc99-9c0b-4ef8-fb6d-6bb9bd380a11}",
     ].each do |valid_uuid|
       uuid = UUIDType.new guid: valid_uuid
       assert_not_nil uuid.guid
     end
 
     # Invalid uuids
-    [['A0EEBC99-9C0B-4EF8-BB6D-6BB9BD380A11'],
+    [["A0EEBC99-9C0B-4EF8-BB6D-6BB9BD380A11"],
      Hash.new,
      0,
      0.0,
      true,
-     'Z0000C99-9C0B-4EF8-BB6D-6BB9BD380A11',
-     'a0eebc999r0b4ef8ab6d6bb9bd380a11',
-     'a0ee-bc99------4ef8-bb6d-6bb9-bd38-0a11',
-     '{a0eebc99-bb6d6bb9-bd380a11}'].each do |invalid_uuid|
+     "Z0000C99-9C0B-4EF8-BB6D-6BB9BD380A11",
+     "a0eebc999r0b4ef8ab6d6bb9bd380a11",
+     "a0ee-bc99------4ef8-bb6d-6bb9-bd38-0a11",
+     "{a0eebc99-bb6d6bb9-bd380a11}",
+     "{a0eebc99-9c0b4ef8-bb6d6bb9-bd380a11",
+     "a0eebc99-9c0b4ef8-bb6d6bb9-bd380a11}"].each do |invalid_uuid|
       uuid = UUIDType.new guid: invalid_uuid
       assert_nil uuid.guid
     end
@@ -142,71 +187,102 @@ class PostgresqlUUIDGenerationTest < ActiveRecord::PostgreSQLTestCase
   include SchemaDumpingHelper
 
   class UUID < ActiveRecord::Base
-    self.table_name = 'pg_uuids'
+    self.table_name = "pg_uuids"
   end
 
   setup do
-    connection.create_table('pg_uuids', id: :uuid, default: 'uuid_generate_v1()') do |t|
-      t.string 'name'
-      t.uuid 'other_uuid', default: 'uuid_generate_v4()'
+    connection.create_table("pg_uuids", id: :uuid, default: "uuid_generate_v1()") do |t|
+      t.string "name"
+      t.uuid "other_uuid", default: "uuid_generate_v4()"
     end
 
     # Create custom PostgreSQL function to generate UUIDs
     # to test dumping tables which columns have defaults with custom functions
     connection.execute <<-SQL
     CREATE OR REPLACE FUNCTION my_uuid_generator() RETURNS uuid
-    AS $$ SELECT * FROM uuid_generate_v4() $$
+    AS $$ SELECT * FROM #{uuid_function} $$
     LANGUAGE SQL VOLATILE;
     SQL
 
     # Create such a table with custom function as default value generator
-    connection.create_table('pg_uuids_2', id: :uuid, default: 'my_uuid_generator()') do |t|
-      t.string 'name'
-      t.uuid 'other_uuid_2', default: 'my_uuid_generator()'
+    connection.create_table("pg_uuids_2", id: :uuid, default: "my_uuid_generator()") do |t|
+      t.string "name"
+      t.uuid "other_uuid_2", default: "my_uuid_generator()"
+    end
+
+    connection.create_table("pg_uuids_3", id: :uuid, **uuid_default) do |t|
+      t.string "name"
     end
   end
 
   teardown do
     drop_table "pg_uuids"
-    drop_table 'pg_uuids_2'
-    connection.execute 'DROP FUNCTION IF EXISTS my_uuid_generator();'
+    drop_table "pg_uuids_2"
+    drop_table "pg_uuids_3"
+    connection.execute "DROP FUNCTION IF EXISTS my_uuid_generator();"
   end
 
-  if ActiveRecord::Base.connection.supports_extensions?
-    def test_id_is_uuid
-      assert_equal :uuid, UUID.columns_hash['id'].type
-      assert UUID.primary_key
-    end
+  def test_id_is_uuid
+    assert_equal :uuid, UUID.columns_hash["id"].type
+    assert UUID.primary_key
+  end
 
-    def test_id_has_a_default
-      u = UUID.create
-      assert_not_nil u.id
-    end
+  def test_id_has_a_default
+    u = UUID.create
+    assert_not_nil u.id
+  end
 
-    def test_auto_create_uuid
-      u = UUID.create
-      u.reload
-      assert_not_nil u.other_uuid
-    end
+  def test_auto_create_uuid
+    u = UUID.create
+    u.reload
+    assert_not_nil u.other_uuid
+  end
 
-    def test_pk_and_sequence_for_uuid_primary_key
-      pk, seq = connection.pk_and_sequence_for('pg_uuids')
-      assert_equal 'id', pk
-      assert_equal nil, seq
-    end
+  def test_pk_and_sequence_for_uuid_primary_key
+    pk, seq = connection.pk_and_sequence_for("pg_uuids")
+    assert_equal "id", pk
+    assert_nil seq
+  end
 
-    def test_schema_dumper_for_uuid_primary_key
-      schema = dump_table_schema "pg_uuids"
-      assert_match(/\bcreate_table "pg_uuids", id: :uuid, default: -> { "uuid_generate_v1\(\)" }/, schema)
-      assert_match(/t\.uuid   "other_uuid", default: -> { "uuid_generate_v4\(\)" }/, schema)
-    end
+  def test_schema_dumper_for_uuid_primary_key
+    schema = dump_table_schema "pg_uuids"
+    assert_match(/\bcreate_table "pg_uuids", id: :uuid, default: -> { "uuid_generate_v1\(\)" }/, schema)
+    assert_match(/t\.uuid "other_uuid", default: -> { "uuid_generate_v4\(\)" }/, schema)
+  end
+
+  def test_schema_dumper_for_uuid_primary_key_with_custom_default
+    schema = dump_table_schema "pg_uuids_2"
+    assert_match(/\bcreate_table "pg_uuids_2", id: :uuid, default: -> { "my_uuid_generator\(\)" }/, schema)
+    assert_match(/t\.uuid "other_uuid_2", default: -> { "my_uuid_generator\(\)" }/, schema)
+  end
 
-    def test_schema_dumper_for_uuid_primary_key_with_custom_default
-      schema = dump_table_schema "pg_uuids_2"
-      assert_match(/\bcreate_table "pg_uuids_2", id: :uuid, default: -> { "my_uuid_generator\(\)" }/, schema)
-      assert_match(/t\.uuid   "other_uuid_2", default: -> { "my_uuid_generator\(\)" }/, schema)
+  def test_schema_dumper_for_uuid_primary_key_default
+    schema = dump_table_schema "pg_uuids_3"
+    if connection.supports_pgcrypto_uuid?
+      assert_match(/\bcreate_table "pg_uuids_3", id: :uuid, default: -> { "gen_random_uuid\(\)" }/, schema)
+    else
+      assert_match(/\bcreate_table "pg_uuids_3", id: :uuid, default: -> { "uuid_generate_v4\(\)" }/, schema)
     end
   end
+
+  def test_schema_dumper_for_uuid_primary_key_default_in_legacy_migration
+    @verbose_was = ActiveRecord::Migration.verbose
+    ActiveRecord::Migration.verbose = false
+
+    migration = Class.new(ActiveRecord::Migration[5.0]) do
+      def version; 101 end
+      def migrate(x)
+        create_table("pg_uuids_4", id: :uuid)
+      end
+    end.new
+    ActiveRecord::Migrator.new(:up, [migration]).migrate
+
+    schema = dump_table_schema "pg_uuids_4"
+    assert_match(/\bcreate_table "pg_uuids_4", id: :uuid, default: -> { "uuid_generate_v4\(\)" }/, schema)
+  ensure
+    drop_table "pg_uuids_4"
+    ActiveRecord::Migration.verbose = @verbose_was
+  end
 end
 
 class PostgresqlUUIDTestNilDefault < ActiveRecord::PostgreSQLTestCase
@@ -214,9 +290,9 @@ class PostgresqlUUIDTestNilDefault < ActiveRecord::PostgreSQLTestCase
   include SchemaDumpingHelper
 
   setup do
-    connection.create_table('pg_uuids', id: false) do |t|
+    connection.create_table("pg_uuids", id: false) do |t|
       t.primary_key :id, :uuid, default: nil
-      t.string 'name'
+      t.string "name"
     end
   end
 
@@ -224,19 +300,36 @@ class PostgresqlUUIDTestNilDefault < ActiveRecord::PostgreSQLTestCase
     drop_table "pg_uuids"
   end
 
-  if ActiveRecord::Base.connection.supports_extensions?
-    def test_id_allows_default_override_via_nil
-      col_desc = connection.execute("SELECT pg_get_expr(d.adbin, d.adrelid) as default
-                                    FROM pg_attribute a
-                                    LEFT JOIN pg_attrdef d ON a.attrelid = d.adrelid AND a.attnum = d.adnum
-                                    WHERE a.attname='id' AND a.attrelid = 'pg_uuids'::regclass").first
-      assert_nil col_desc["default"]
-    end
+  def test_id_allows_default_override_via_nil
+    col_desc = connection.execute("SELECT pg_get_expr(d.adbin, d.adrelid) as default
+                                  FROM pg_attribute a
+                                  LEFT JOIN pg_attrdef d ON a.attrelid = d.adrelid AND a.attnum = d.adnum
+                                  WHERE a.attname='id' AND a.attrelid = 'pg_uuids'::regclass").first
+    assert_nil col_desc["default"]
+  end
 
-    def test_schema_dumper_for_uuid_primary_key_with_default_override_via_nil
-      schema = dump_table_schema "pg_uuids"
-      assert_match(/\bcreate_table "pg_uuids", id: :uuid, default: nil/, schema)
-    end
+  def test_schema_dumper_for_uuid_primary_key_with_default_override_via_nil
+    schema = dump_table_schema "pg_uuids"
+    assert_match(/\bcreate_table "pg_uuids", id: :uuid, default: nil/, schema)
+  end
+
+  def test_schema_dumper_for_uuid_primary_key_with_default_nil_in_legacy_migration
+    @verbose_was = ActiveRecord::Migration.verbose
+    ActiveRecord::Migration.verbose = false
+
+    migration = Class.new(ActiveRecord::Migration[5.0]) do
+      def version; 101 end
+      def migrate(x)
+        create_table("pg_uuids_4", id: :uuid, default: nil)
+      end
+    end.new
+    ActiveRecord::Migrator.new(:up, [migration]).migrate
+
+    schema = dump_table_schema "pg_uuids_4"
+    assert_match(/\bcreate_table "pg_uuids_4", id: :uuid, default: nil/, schema)
+  ensure
+    drop_table "pg_uuids_4"
+    ActiveRecord::Migration.verbose = @verbose_was
   end
 end
 
@@ -244,51 +337,47 @@ class PostgresqlUUIDTestInverseOf < ActiveRecord::PostgreSQLTestCase
   include PostgresqlUUIDHelper
 
   class UuidPost < ActiveRecord::Base
-    self.table_name = 'pg_uuid_posts'
+    self.table_name = "pg_uuid_posts"
     has_many :uuid_comments, inverse_of: :uuid_post
   end
 
   class UuidComment < ActiveRecord::Base
-    self.table_name = 'pg_uuid_comments'
+    self.table_name = "pg_uuid_comments"
     belongs_to :uuid_post
   end
 
   setup do
     connection.transaction do
-      connection.create_table('pg_uuid_posts', id: :uuid) do |t|
-        t.string 'title'
+      connection.create_table("pg_uuid_posts", id: :uuid, **uuid_default) do |t|
+        t.string "title"
       end
-      connection.create_table('pg_uuid_comments', id: :uuid) do |t|
+      connection.create_table("pg_uuid_comments", id: :uuid, **uuid_default) do |t|
         t.references :uuid_post, type: :uuid
-        t.string 'content'
+        t.string "content"
       end
     end
   end
 
   teardown do
-      drop_table "pg_uuid_comments"
-      drop_table "pg_uuid_posts"
+    drop_table "pg_uuid_comments"
+    drop_table "pg_uuid_posts"
   end
 
-  if ActiveRecord::Base.connection.supports_extensions?
-    def test_collection_association_with_uuid
-      post    = UuidPost.create!
-      comment = post.uuid_comments.create!
-      assert post.uuid_comments.find(comment.id)
-    end
-
-    def test_find_with_uuid
-      UuidPost.create!
-      assert_raise ActiveRecord::RecordNotFound do
-        UuidPost.find(123456)
-      end
-
-    end
+  def test_collection_association_with_uuid
+    post    = UuidPost.create!
+    comment = post.uuid_comments.create!
+    assert post.uuid_comments.find(comment.id)
+  end
 
-    def test_find_by_with_uuid
-      UuidPost.create!
-      assert_nil UuidPost.find_by(id: 789)
+  def test_find_with_uuid
+    UuidPost.create!
+    assert_raise ActiveRecord::RecordNotFound do
+      UuidPost.find(123456)
     end
   end
 
+  def test_find_by_with_uuid
+    UuidPost.create!
+    assert_nil UuidPost.find_by(id: 789)
+  end
 end
diff --git a/activerecord/test/cases/adapters/postgresql/xml_test.rb b/activerecord/test/cases/adapters/postgresql/xml_test.rb
index add32699fa..71ead6f7f3 100644
--- a/activerecord/test/cases/adapters/postgresql/xml_test.rb
+++ b/activerecord/test/cases/adapters/postgresql/xml_test.rb
@@ -1,28 +1,30 @@
-require 'cases/helper'
-require 'support/schema_dumping_helper'
+# frozen_string_literal: true
+
+require "cases/helper"
+require "support/schema_dumping_helper"
 
 class PostgresqlXMLTest < ActiveRecord::PostgreSQLTestCase
   include SchemaDumpingHelper
   class XmlDataType < ActiveRecord::Base
-    self.table_name = 'xml_data_type'
+    self.table_name = "xml_data_type"
   end
 
   def setup
     @connection = ActiveRecord::Base.connection
     begin
       @connection.transaction do
-        @connection.create_table('xml_data_type') do |t|
-          t.xml 'payload'
+        @connection.create_table("xml_data_type") do |t|
+          t.xml "payload"
         end
       end
     rescue ActiveRecord::StatementInvalid
       skip "do not test on PG without xml"
     end
-    @column = XmlDataType.columns_hash['payload']
+    @column = XmlDataType.columns_hash["payload"]
   end
 
   teardown do
-    @connection.drop_table 'xml_data_type', if_exists: true
+    @connection.drop_table "xml_data_type", if_exists: true
   end
 
   def test_column
@@ -30,7 +32,7 @@ class PostgresqlXMLTest < ActiveRecord::PostgreSQLTestCase
   end
 
   def test_null_xml
-    @connection.execute %q|insert into xml_data_type (payload) VALUES(null)|
+    @connection.execute "insert into xml_data_type (payload) VALUES(null)"
     assert_nil XmlDataType.first.payload
   end
 
diff --git a/activerecord/test/cases/adapters/sqlite3/collation_test.rb b/activerecord/test/cases/adapters/sqlite3/collation_test.rb
index 58a9469ce5..76c8f7d8dd 100644
--- a/activerecord/test/cases/adapters/sqlite3/collation_test.rb
+++ b/activerecord/test/cases/adapters/sqlite3/collation_test.rb
@@ -1,5 +1,7 @@
+# frozen_string_literal: true
+
 require "cases/helper"
-require 'support/schema_dumping_helper'
+require "support/schema_dumping_helper"
 
 class SQLite3CollationTest < ActiveRecord::SQLite3TestCase
   include SchemaDumpingHelper
@@ -7,8 +9,8 @@ class SQLite3CollationTest < ActiveRecord::SQLite3TestCase
   def setup
     @connection = ActiveRecord::Base.connection
     @connection.create_table :collation_table_sqlite3, force: true do |t|
-      t.string :string_nocase, collation: 'NOCASE'
-      t.text :text_rtrim, collation: 'RTRIM'
+      t.string :string_nocase, collation: "NOCASE"
+      t.text :text_rtrim, collation: "RTRIM"
     end
   end
 
@@ -17,37 +19,37 @@ class SQLite3CollationTest < ActiveRecord::SQLite3TestCase
   end
 
   test "string column with collation" do
-    column = @connection.columns(:collation_table_sqlite3).find { |c| c.name == 'string_nocase' }
+    column = @connection.columns(:collation_table_sqlite3).find { |c| c.name == "string_nocase" }
     assert_equal :string, column.type
-    assert_equal 'NOCASE', column.collation
+    assert_equal "NOCASE", column.collation
   end
 
   test "text column with collation" do
-    column = @connection.columns(:collation_table_sqlite3).find { |c| c.name == 'text_rtrim' }
+    column = @connection.columns(:collation_table_sqlite3).find { |c| c.name == "text_rtrim" }
     assert_equal :text, column.type
-    assert_equal 'RTRIM', column.collation
+    assert_equal "RTRIM", column.collation
   end
 
   test "add column with collation" do
-    @connection.add_column :collation_table_sqlite3, :title, :string, collation: 'RTRIM'
+    @connection.add_column :collation_table_sqlite3, :title, :string, collation: "RTRIM"
 
-    column = @connection.columns(:collation_table_sqlite3).find { |c| c.name == 'title' }
+    column = @connection.columns(:collation_table_sqlite3).find { |c| c.name == "title" }
     assert_equal :string, column.type
-    assert_equal 'RTRIM', column.collation
+    assert_equal "RTRIM", column.collation
   end
 
   test "change column with collation" do
     @connection.add_column :collation_table_sqlite3, :description, :string
-    @connection.change_column :collation_table_sqlite3, :description, :text, collation: 'RTRIM'
+    @connection.change_column :collation_table_sqlite3, :description, :text, collation: "RTRIM"
 
-    column = @connection.columns(:collation_table_sqlite3).find { |c| c.name == 'description' }
+    column = @connection.columns(:collation_table_sqlite3).find { |c| c.name == "description" }
     assert_equal :text, column.type
-    assert_equal 'RTRIM', column.collation
+    assert_equal "RTRIM", column.collation
   end
 
   test "schema dump includes collation" do
     output = dump_table_schema("collation_table_sqlite3")
-    assert_match %r{t.string\s+"string_nocase",\s+collation: "NOCASE"$}, output
-    assert_match %r{t.text\s+"text_rtrim",\s+collation: "RTRIM"$}, output
+    assert_match %r{t\.string\s+"string_nocase",\s+collation: "NOCASE"$}, output
+    assert_match %r{t\.text\s+"text_rtrim",\s+collation: "RTRIM"$}, output
   end
 end
diff --git a/activerecord/test/cases/adapters/sqlite3/copy_table_test.rb b/activerecord/test/cases/adapters/sqlite3/copy_table_test.rb
index 34e3b2e023..ffb1d6afce 100644
--- a/activerecord/test/cases/adapters/sqlite3/copy_table_test.rb
+++ b/activerecord/test/cases/adapters/sqlite3/copy_table_test.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require "cases/helper"
 
 class CopyTableTest < ActiveRecord::SQLite3TestCase
@@ -10,8 +12,8 @@ class CopyTableTest < ActiveRecord::SQLite3TestCase
     end
   end
 
-  def test_copy_table(from = 'customers', to = 'customers2', options = {})
-    assert_nothing_raised {copy_table(from, to, options)}
+  def test_copy_table(from = "customers", to = "customers2", options = {})
+    assert_nothing_raised { copy_table(from, to, options) }
     assert_equal row_count(from), row_count(to)
 
     if block_given?
@@ -24,68 +26,69 @@ class CopyTableTest < ActiveRecord::SQLite3TestCase
   end
 
   def test_copy_table_renaming_column
-    test_copy_table('customers', 'customers2',
-        :rename => {'name' => 'person_name'}) do |from, to, options|
-      expected = column_values(from, 'name')
-      assert_equal expected, column_values(to, 'person_name')
+    test_copy_table("customers", "customers2",
+        rename: { "name" => "person_name" }) do |from, to, options|
+      expected = column_values(from, "name")
+      assert_equal expected, column_values(to, "person_name")
       assert expected.any?, "No values in table: #{expected.inspect}"
     end
   end
 
   def test_copy_table_allows_to_pass_options_to_create_table
-    @connection.create_table('blocker_table')
-    test_copy_table('customers', 'blocker_table', force: true)
+    @connection.create_table("blocker_table")
+    test_copy_table("customers", "blocker_table", force: true)
   end
 
   def test_copy_table_with_index
-    test_copy_table('comments', 'comments_with_index') do
-      @connection.add_index('comments_with_index', ['post_id', 'type'])
-      test_copy_table('comments_with_index', 'comments_with_index2') do
-        assert_equal table_indexes_without_name('comments_with_index'),
-                     table_indexes_without_name('comments_with_index2')
+    test_copy_table("comments", "comments_with_index") do
+      @connection.add_index("comments_with_index", ["post_id", "type"])
+      test_copy_table("comments_with_index", "comments_with_index2") do
+        assert_nil table_indexes_without_name("comments_with_index")
+        assert_nil table_indexes_without_name("comments_with_index2")
       end
     end
   end
 
   def test_copy_table_without_primary_key
-    test_copy_table('developers_projects', 'programmers_projects') do
-      assert_nil @connection.primary_key('programmers_projects')
+    test_copy_table("developers_projects", "programmers_projects") do
+      assert_nil @connection.primary_key("programmers_projects")
     end
   end
 
   def test_copy_table_with_id_col_that_is_not_primary_key
-    test_copy_table('goofy_string_id', 'goofy_string_id2') do
-      original_id = @connection.columns('goofy_string_id').detect{|col| col.name == 'id' }
-      copied_id = @connection.columns('goofy_string_id2').detect{|col| col.name == 'id' }
+    test_copy_table("goofy_string_id", "goofy_string_id2") do
+      original_id = @connection.columns("goofy_string_id").detect { |col| col.name == "id" }
+      copied_id = @connection.columns("goofy_string_id2").detect { |col| col.name == "id" }
       assert_equal original_id.type, copied_id.type
       assert_equal original_id.sql_type, copied_id.sql_type
-      assert_equal original_id.limit, copied_id.limit
+      assert_nil original_id.limit
+      assert_nil copied_id.limit
     end
   end
 
   def test_copy_table_with_unconventional_primary_key
-    test_copy_table('owners', 'owners_unconventional') do
-      original_pk = @connection.primary_key('owners')
-      copied_pk = @connection.primary_key('owners_unconventional')
+    test_copy_table("owners", "owners_unconventional") do
+      original_pk = @connection.primary_key("owners")
+      copied_pk = @connection.primary_key("owners_unconventional")
       assert_equal original_pk, copied_pk
     end
   end
 
   def test_copy_table_with_binary_column
-    test_copy_table 'binaries', 'binaries2'
+    test_copy_table "binaries", "binaries2"
   end
 
-protected
+private
   def copy_table(from, to, options = {})
-    @connection.copy_table(from, to, {:temporary => true}.merge(options))
+    @connection.copy_table(from, to, { temporary: true }.merge(options))
   end
 
   def column_names(table)
-    @connection.table_structure(table).map {|column| column['name']}
+    @connection.table_structure(table).map { |column| column["name"] }
   end
 
   def column_values(table, column)
-    @connection.select_all("SELECT #{column} FROM #{table} ORDER BY id").map {|row| row[column]}
+    @connection.select_all("SELECT #{column} FROM #{table} ORDER BY id").map { |row| row[column] }
   end
 
   def table_indexes_without_name(table)
@@ -93,6 +96,6 @@ protected
   end
 
   def row_count(table)
-    @connection.select_one("SELECT COUNT(*) AS count FROM #{table}")['count']
+    @connection.select_one("SELECT COUNT(*) AS count FROM #{table}")["count"]
   end
 end
diff --git a/activerecord/test/cases/adapters/sqlite3/explain_test.rb b/activerecord/test/cases/adapters/sqlite3/explain_test.rb
index a1a6e5f16a..b6d2ccdb53 100644
--- a/activerecord/test/cases/adapters/sqlite3/explain_test.rb
+++ b/activerecord/test/cases/adapters/sqlite3/explain_test.rb
@@ -1,21 +1,23 @@
+# frozen_string_literal: true
+
 require "cases/helper"
-require 'models/developer'
-require 'models/computer'
+require "models/author"
+require "models/post"
 
 class SQLite3ExplainTest < ActiveRecord::SQLite3TestCase
-  fixtures :developers
+  fixtures :authors
 
   def test_explain_for_one_query
-    explain = Developer.where(id: 1).explain
-    assert_match %r(EXPLAIN for: SELECT "developers".* FROM "developers" WHERE "developers"."id" = (?:\?|1)), explain
-    assert_match(/(SEARCH )?TABLE developers USING (INTEGER )?PRIMARY KEY/, explain)
+    explain = Author.where(id: 1).explain
+    assert_match %r(EXPLAIN for: SELECT "authors"\.\* FROM "authors" WHERE "authors"\."id" = (?:\? \[\["id", 1\]\]|1)), explain
+    assert_match(/(SEARCH )?TABLE authors USING (INTEGER )?PRIMARY KEY/, explain)
   end
 
   def test_explain_with_eager_loading
-    explain = Developer.where(id: 1).includes(:audit_logs).explain
-    assert_match %r(EXPLAIN for: SELECT "developers".* FROM "developers" WHERE "developers"."id" = (?:\?|1)), explain
-    assert_match(/(SEARCH )?TABLE developers USING (INTEGER )?PRIMARY KEY/, explain)
-    assert_match %(EXPLAIN for: SELECT "audit_logs".* FROM "audit_logs" WHERE "audit_logs"."developer_id" = 1), explain
-    assert_match(/(SCAN )?TABLE audit_logs/, explain)
+    explain = Author.where(id: 1).includes(:posts).explain
+    assert_match %r(EXPLAIN for: SELECT "authors"\.\* FROM "authors" WHERE "authors"\."id" = (?:\? \[\["id", 1\]\]|1)), explain
+    assert_match(/(SEARCH )?TABLE authors USING (INTEGER )?PRIMARY KEY/, explain)
+    assert_match %r(EXPLAIN for: SELECT "posts"\.\* FROM "posts" WHERE "posts"\."author_id" = (?:\? \[\["author_id", 1\]\]|1)), explain
+    assert_match(/(SCAN )?TABLE posts/, explain)
   end
 end
diff --git a/activerecord/test/cases/adapters/sqlite3/json_test.rb b/activerecord/test/cases/adapters/sqlite3/json_test.rb
new file mode 100644
index 0000000000..6f247fcd22
--- /dev/null
+++ b/activerecord/test/cases/adapters/sqlite3/json_test.rb
@@ -0,0 +1,29 @@
+# frozen_string_literal: true
+
+require "cases/helper"
+require "cases/json_shared_test_cases"
+
+class SQLite3JSONTest < ActiveRecord::SQLite3TestCase
+  include JSONSharedTestCases
+
+  def setup
+    super
+    @connection.create_table("json_data_type") do |t|
+      t.json "payload", default: {}
+      t.json "settings"
+    end
+  end
+
+  def test_default
+    @connection.add_column "json_data_type", "permissions", column_type, default: { "users": "read", "posts": ["read", "write"] }
+    klass.reset_column_information
+
+    assert_equal({ "users" => "read", "posts" => ["read", "write"] }, klass.column_defaults["permissions"])
+    assert_equal({ "users" => "read", "posts" => ["read", "write"] }, klass.new.permissions)
+  end
+
+  private
+    def column_type
+      :json
+    end
+end
diff --git a/activerecord/test/cases/adapters/sqlite3/quoting_test.rb b/activerecord/test/cases/adapters/sqlite3/quoting_test.rb
index fe2425b845..6fdb353368 100644
--- a/activerecord/test/cases/adapters/sqlite3/quoting_test.rb
+++ b/activerecord/test/cases/adapters/sqlite3/quoting_test.rb
@@ -1,11 +1,17 @@
+# frozen_string_literal: true
+
 require "cases/helper"
-require 'bigdecimal'
-require 'yaml'
-require 'securerandom'
+require "bigdecimal"
+require "securerandom"
 
 class SQLite3QuotingTest < ActiveRecord::SQLite3TestCase
   def setup
     @conn = ActiveRecord::Base.connection
+    @initial_represent_boolean_as_integer = ActiveRecord::ConnectionAdapters::SQLite3Adapter.represent_boolean_as_integer
+  end
+
+  def teardown
+    ActiveRecord::ConnectionAdapters::SQLite3Adapter.represent_boolean_as_integer = @initial_represent_boolean_as_integer
   end
 
   def test_type_cast_binary_encoding_without_logger
@@ -15,71 +21,29 @@ class SQLite3QuotingTest < ActiveRecord::SQLite3TestCase
     assert_equal expected, @conn.type_cast(binary)
   end
 
-  def test_type_cast_symbol
-    assert_equal 'foo', @conn.type_cast(:foo)
-  end
-
-  def test_type_cast_date
-    date = Date.today
-    expected = @conn.quoted_date(date)
-    assert_equal expected, @conn.type_cast(date)
-  end
-
-  def test_type_cast_time
-    time = Time.now
-    expected = @conn.quoted_date(time)
-    assert_equal expected, @conn.type_cast(time)
-  end
-
-  def test_type_cast_numeric
-    assert_equal 10, @conn.type_cast(10)
-    assert_equal 2.2, @conn.type_cast(2.2)
-  end
-
-  def test_type_cast_nil
-    assert_equal nil, @conn.type_cast(nil)
-  end
-
   def test_type_cast_true
-    assert_equal 't', @conn.type_cast(true)
+    ActiveRecord::ConnectionAdapters::SQLite3Adapter.represent_boolean_as_integer = false
+    assert_equal "t", @conn.type_cast(true)
+
+    ActiveRecord::ConnectionAdapters::SQLite3Adapter.represent_boolean_as_integer = true
+    assert_equal 1, @conn.type_cast(true)
   end
 
   def test_type_cast_false
-    assert_equal 'f', @conn.type_cast(false)
+    ActiveRecord::ConnectionAdapters::SQLite3Adapter.represent_boolean_as_integer = false
+    assert_equal "f", @conn.type_cast(false)
+
+    ActiveRecord::ConnectionAdapters::SQLite3Adapter.represent_boolean_as_integer = true
+    assert_equal 0, @conn.type_cast(false)
   end
 
   def test_type_cast_bigdecimal
-    bd = BigDecimal.new '10.0'
+    bd = BigDecimal "10.0"
     assert_equal bd.to_f, @conn.type_cast(bd)
   end
 
-  def test_type_cast_unknown_should_raise_error
-    obj = Class.new.new
-    assert_raise(TypeError) { @conn.type_cast(obj) }
-  end
-
-  def test_type_cast_object_which_responds_to_quoted_id
-    quoted_id_obj = Class.new {
-      def quoted_id
-        "'zomg'"
-      end
-
-      def id
-        10
-      end
-    }.new
-    assert_equal 10, @conn.type_cast(quoted_id_obj)
-
-    quoted_id_obj = Class.new {
-      def quoted_id
-        "'zomg'"
-      end
-    }.new
-    assert_raise(TypeError) { @conn.type_cast(quoted_id_obj) }
-  end
-
   def test_quoting_binary_strings
-    value = "hello".encode('ascii-8bit')
+    value = "hello".encode("ascii-8bit")
     type = ActiveRecord::Type::String.new
 
     assert_equal "'hello'", @conn.quote(type.serialize(value))
diff --git a/activerecord/test/cases/adapters/sqlite3/sqlite3_adapter_test.rb b/activerecord/test/cases/adapters/sqlite3/sqlite3_adapter_test.rb
index bbc9f978bf..cd5d6f17d8 100644
--- a/activerecord/test/cases/adapters/sqlite3/sqlite3_adapter_test.rb
+++ b/activerecord/test/cases/adapters/sqlite3/sqlite3_adapter_test.rb
@@ -1,7 +1,9 @@
+# frozen_string_literal: true
+
 require "cases/helper"
-require 'models/owner'
-require 'tempfile'
-require 'support/ddl_helper'
+require "models/owner"
+require "tempfile"
+require "support/ddl_helper"
 
 module ActiveRecord
   module ConnectionAdapters
@@ -14,22 +16,22 @@ module ActiveRecord
       end
 
       def setup
-        @conn = Base.sqlite3_connection database: ':memory:',
-                                        adapter: 'sqlite3',
+        @conn = Base.sqlite3_connection database: ":memory:",
+                                        adapter: "sqlite3",
                                         timeout: 100
       end
 
       def test_bad_connection
         assert_raise ActiveRecord::NoDatabaseError do
           connection = ActiveRecord::Base.sqlite3_connection(adapter: "sqlite3", database: "/tmp/should/_not/_exist/-cinco-dog.db")
-          connection.drop_table 'ex', if_exists: true
+          connection.drop_table "ex", if_exists: true
         end
       end
 
       unless in_memory_db?
         def test_connect_with_url
           original_connection = ActiveRecord::Base.remove_connection
-          tf = Tempfile.open 'whatever'
+          tf = Tempfile.open "whatever"
           url = "sqlite3:#{tf.path}"
           ActiveRecord::Base.establish_connection(url)
           assert ActiveRecord::Base.connection
@@ -49,26 +51,10 @@ module ActiveRecord
         end
       end
 
-      def test_valid_column
-        with_example_table do
-          column = @conn.columns('ex').find { |col| col.name == 'id' }
-          assert @conn.valid_type?(column.type)
-        end
-      end
-
-      # sqlite3 databases should be able to support any type and not just the
-      # ones mentioned in the native_database_types.
-      #
-      # Therefore test_invalid column should always return true even if the
-      # type is not valid.
-      def test_invalid_column
-        assert @conn.valid_type?(:foobar)
-      end
-
       def test_column_types
-        owner = Owner.create!(name: "hello".encode('ascii-8bit'))
+        owner = Owner.create!(name: "hello".encode("ascii-8bit"))
         owner.reload
-        select = Owner.columns.map { |c| "typeof(#{c.name})" }.join ', '
+        select = Owner.columns.map { |c| "typeof(#{c.name})" }.join ", "
         result = Owner.connection.exec_query <<-esql
           SELECT #{select}
           FROM   #{Owner.table_name}
@@ -83,10 +69,10 @@ module ActiveRecord
       def test_exec_insert
         with_example_table do
           vals = [Relation::QueryAttribute.new("number", 10, Type::Value.new)]
-          @conn.exec_insert('insert into ex (number) VALUES (?)', 'SQL', vals)
+          @conn.exec_insert("insert into ex (number) VALUES (?)", "SQL", vals)
 
           result = @conn.exec_query(
-            'select number from ex where number = ?', 'SQL', vals)
+            "select number from ex where number = ?", "SQL", vals)
 
           assert_equal 1, result.rows.length
           assert_equal 10, result.rows.first.first
@@ -94,8 +80,8 @@ module ActiveRecord
       end
 
       def test_primary_key_returns_nil_for_no_pk
-        with_example_table 'id int, data string' do
-          assert_nil @conn.primary_key('ex')
+        with_example_table "id int, data string" do
+          assert_nil @conn.primary_key("ex")
         end
       end
 
@@ -107,69 +93,69 @@ module ActiveRecord
 
       def test_bad_timeout
         assert_raises(TypeError) do
-          Base.sqlite3_connection database: ':memory:',
-                                  adapter: 'sqlite3',
-                                  timeout: 'usa'
+          Base.sqlite3_connection database: ":memory:",
+                                  adapter: "sqlite3",
+                                  timeout: "usa"
         end
       end
 
       # connection is OK with a nil timeout
       def test_nil_timeout
-        conn = Base.sqlite3_connection database: ':memory:',
-                                       adapter: 'sqlite3',
+        conn = Base.sqlite3_connection database: ":memory:",
+                                       adapter: "sqlite3",
                                        timeout: nil
-        assert conn, 'made a connection'
+        assert conn, "made a connection"
       end
 
       def test_connect
-        assert @conn, 'should have connection'
+        assert @conn, "should have connection"
       end
 
       # sqlite3 defaults to UTF-8 encoding
       def test_encoding
-        assert_equal 'UTF-8', @conn.encoding
+        assert_equal "UTF-8", @conn.encoding
       end
 
       def test_exec_no_binds
-        with_example_table 'id int, data string' do
-          result = @conn.exec_query('SELECT id, data FROM ex')
+        with_example_table "id int, data string" do
+          result = @conn.exec_query("SELECT id, data FROM ex")
           assert_equal 0, result.rows.length
           assert_equal 2, result.columns.length
           assert_equal %w{ id data }, result.columns
 
           @conn.exec_query('INSERT INTO ex (id, data) VALUES (1, "foo")')
-          result = @conn.exec_query('SELECT id, data FROM ex')
+          result = @conn.exec_query("SELECT id, data FROM ex")
           assert_equal 1, result.rows.length
           assert_equal 2, result.columns.length
 
-          assert_equal [[1, 'foo']], result.rows
+          assert_equal [[1, "foo"]], result.rows
         end
       end
 
       def test_exec_query_with_binds
-        with_example_table 'id int, data string' do
+        with_example_table "id int, data string" do
           @conn.exec_query('INSERT INTO ex (id, data) VALUES (1, "foo")')
           result = @conn.exec_query(
-            'SELECT id, data FROM ex WHERE id = ?', nil, [Relation::QueryAttribute.new(nil, 1, Type::Value.new)])
+            "SELECT id, data FROM ex WHERE id = ?", nil, [Relation::QueryAttribute.new(nil, 1, Type::Value.new)])
 
           assert_equal 1, result.rows.length
           assert_equal 2, result.columns.length
 
-          assert_equal [[1, 'foo']], result.rows
+          assert_equal [[1, "foo"]], result.rows
         end
       end
 
       def test_exec_query_typecasts_bind_vals
-        with_example_table 'id int, data string' do
+        with_example_table "id int, data string" do
           @conn.exec_query('INSERT INTO ex (id, data) VALUES (1, "foo")')
 
           result = @conn.exec_query(
-            'SELECT id, data FROM ex WHERE id = ?', nil, [Relation::QueryAttribute.new("id", "1-fuu", Type::Integer.new)])
+            "SELECT id, data FROM ex WHERE id = ?", nil, [Relation::QueryAttribute.new("id", "1-fuu", Type::Integer.new)])
 
           assert_equal 1, result.rows.length
           assert_equal 2, result.columns.length
 
-          assert_equal [[1, 'foo']], result.rows
+          assert_equal [[1, "foo"]], result.rows
         end
       end
 
@@ -181,16 +167,16 @@ module ActiveRecord
             data binary
           )
         eosql
-        str = "\x80".force_encoding("ASCII-8BIT")
-        binary = DualEncoding.new name: 'いただきます！', data: str
+        str = "\x80".dup.force_encoding("ASCII-8BIT")
+        binary = DualEncoding.new name: "いただきます！", data: str
         binary.save!
         assert_equal str, binary.data
       ensure
-        DualEncoding.connection.drop_table 'dual_encodings', if_exists: true
+        DualEncoding.connection.drop_table "dual_encodings", if_exists: true
       end
 
       def test_type_cast_should_not_mutate_encoding
-        name  = 'hello'.force_encoding(Encoding::ASCII_8BIT)
+        name = "hello".dup.force_encoding(Encoding::ASCII_8BIT)
         Owner.create(name: name)
         assert_equal Encoding::ASCII_8BIT, name.encoding
       ensure
@@ -204,8 +190,8 @@ module ActiveRecord
           assert_equal 1, records.length
 
           record = records.first
-          assert_equal 10, record['number']
-          assert_equal 1, record['id']
+          assert_equal 10, record["number"]
+          assert_equal 1, record["id"]
         end
       end
 
@@ -226,7 +212,7 @@ module ActiveRecord
       def test_insert_id_value_returned
         with_example_table do
           sql = "INSERT INTO ex (number) VALUES (10)"
-          idval = 'vuvuzela'
+          idval = "vuvuzela"
           id = @conn.insert(sql, nil, nil, idval)
           assert_equal idval, id
         end
@@ -237,7 +223,7 @@ module ActiveRecord
           2.times do |i|
             @conn.create "INSERT INTO ex (number) VALUES (#{i})"
           end
-          rows = @conn.select_rows 'select number, id from ex'
+          rows = @conn.select_rows "select number, id from ex"
           assert_equal [[0, 1], [1, 2]], rows
         end
       end
@@ -254,7 +240,7 @@ module ActiveRecord
 
       def test_transaction
         with_example_table do
-          count_sql = 'select count(*) from ex'
+          count_sql = "select count(*) from ex"
 
           @conn.begin_db_transaction
           @conn.create "INSERT INTO ex (number) VALUES (10)"
@@ -267,50 +253,36 @@ module ActiveRecord
 
       def test_tables
         with_example_table do
-          ActiveSupport::Deprecation.silence { assert_equal %w{ ex }, @conn.tables }
-          with_example_table 'id integer PRIMARY KEY AUTOINCREMENT, number integer', 'people' do
-            ActiveSupport::Deprecation.silence { assert_equal %w{ ex people }.sort, @conn.tables.sort }
+          assert_equal %w{ ex }, @conn.tables
+          with_example_table "id integer PRIMARY KEY AUTOINCREMENT, number integer", "people" do
+            assert_equal %w{ ex people }.sort, @conn.tables.sort
           end
         end
       end
 
       def test_tables_logs_name
         sql = <<-SQL
-          SELECT name FROM sqlite_master
-          WHERE type IN ('table','view') AND name <> 'sqlite_sequence'
+          SELECT name FROM sqlite_master WHERE name <> 'sqlite_sequence' AND type IN ('table')
         SQL
-        assert_logged [[sql.squish, 'SCHEMA', []]] do
-          ActiveSupport::Deprecation.silence do
-            @conn.tables('hello')
-          end
-        end
-      end
-
-      def test_indexes_logs_name
-        with_example_table do
-          assert_logged [["PRAGMA index_list(\"ex\")", 'SCHEMA', []]] do
-            @conn.indexes('ex', 'hello')
-          end
+        assert_logged [[sql.squish, "SCHEMA", []]] do
+          @conn.tables
         end
       end
 
       def test_table_exists_logs_name
         with_example_table do
           sql = <<-SQL
-            SELECT name FROM sqlite_master
-            WHERE type IN ('table','view') AND name <> 'sqlite_sequence' AND name = 'ex'
+            SELECT name FROM sqlite_master WHERE name <> 'sqlite_sequence' AND name = 'ex' AND type IN ('table')
           SQL
-          assert_logged [[sql.squish, 'SCHEMA', []]] do
-            ActiveSupport::Deprecation.silence do
-              assert @conn.table_exists?('ex')
-            end
+          assert_logged [[sql.squish, "SCHEMA", []]] do
+            assert @conn.table_exists?("ex")
           end
         end
       end
 
       def test_columns
         with_example_table do
-          columns = @conn.columns('ex').sort_by(&:name)
+          columns = @conn.columns("ex").sort_by(&:name)
           assert_equal 2, columns.length
           assert_equal %w{ id number }.sort, columns.map(&:name)
           assert_equal [nil, nil], columns.map(&:default)
@@ -319,17 +291,17 @@ module ActiveRecord
       end
 
       def test_columns_with_default
-        with_example_table 'id integer PRIMARY KEY AUTOINCREMENT, number integer default 10' do
-          column = @conn.columns('ex').find { |x|
-            x.name == 'number'
+        with_example_table "id integer PRIMARY KEY AUTOINCREMENT, number integer default 10" do
+          column = @conn.columns("ex").find { |x|
+            x.name == "number"
           }
-          assert_equal '10', column.default
+          assert_equal "10", column.default
         end
       end
 
       def test_columns_with_not_null
-        with_example_table 'id integer PRIMARY KEY AUTOINCREMENT, number integer not null' do
-          column = @conn.columns('ex').find { |x| x.name == 'number' }
+        with_example_table "id integer PRIMARY KEY AUTOINCREMENT, number integer not null" do
+          column = @conn.columns("ex").find { |x| x.name == "number" }
           assert_not column.null, "column should not be null"
         end
       end
@@ -337,59 +309,169 @@ module ActiveRecord
       def test_indexes_logs
         with_example_table do
           assert_logged [["PRAGMA index_list(\"ex\")", "SCHEMA", []]] do
-            @conn.indexes('ex')
+            @conn.indexes("ex")
           end
         end
       end
 
       def test_no_indexes
-        assert_equal [], @conn.indexes('items')
+        assert_equal [], @conn.indexes("items")
       end
 
       def test_index
         with_example_table do
-          @conn.add_index 'ex', 'id', unique: true, name: 'fun'
-          index = @conn.indexes('ex').find { |idx| idx.name == 'fun' }
+          @conn.add_index "ex", "id", unique: true, name: "fun"
+          index = @conn.indexes("ex").find { |idx| idx.name == "fun" }
 
-          assert_equal 'ex', index.table
-          assert index.unique, 'index is unique'
-          assert_equal ['id'], index.columns
+          assert_equal "ex", index.table
+          assert index.unique, "index is unique"
+          assert_equal ["id"], index.columns
         end
       end
 
       def test_non_unique_index
         with_example_table do
-          @conn.add_index 'ex', 'id', name: 'fun'
-          index = @conn.indexes('ex').find { |idx| idx.name == 'fun' }
-          assert_not index.unique, 'index is not unique'
+          @conn.add_index "ex", "id", name: "fun"
+          index = @conn.indexes("ex").find { |idx| idx.name == "fun" }
+          assert_not index.unique, "index is not unique"
         end
       end
 
       def test_compound_index
         with_example_table do
-          @conn.add_index 'ex', %w{ id number }, name: 'fun'
-          index = @conn.indexes('ex').find { |idx| idx.name == 'fun' }
+          @conn.add_index "ex", %w{ id number }, name: "fun"
+          index = @conn.indexes("ex").find { |idx| idx.name == "fun" }
           assert_equal %w{ id number }.sort, index.columns.sort
         end
       end
 
       def test_primary_key
         with_example_table do
-          assert_equal 'id', @conn.primary_key('ex')
-          with_example_table 'internet integer PRIMARY KEY AUTOINCREMENT, number integer not null', 'foos' do
-            assert_equal 'internet', @conn.primary_key('foos')
+          assert_equal "id", @conn.primary_key("ex")
+          with_example_table "internet integer PRIMARY KEY AUTOINCREMENT, number integer not null", "foos" do
+            assert_equal "internet", @conn.primary_key("foos")
           end
         end
       end
 
       def test_no_primary_key
-        with_example_table 'number integer not null' do
-          assert_nil @conn.primary_key('ex')
+        with_example_table "number integer not null" do
+          assert_nil @conn.primary_key("ex")
+        end
+      end
+
+      class Barcode < ActiveRecord::Base
+        self.primary_key = "code"
+      end
+
+      def test_copy_table_with_existing_records_have_custom_primary_key
+        connection = Barcode.connection
+        connection.create_table(:barcodes, primary_key: "code", id: :string, limit: 42, force: true) do |t|
+          t.text :other_attr
+        end
+        code = "214fe0c2-dd47-46df-b53b-66090b3c1d40"
+        Barcode.create!(code: code, other_attr: "xxx")
+
+        connection.remove_column("barcodes", "other_attr")
+
+        assert_equal code, Barcode.first.id
+      ensure
+        Barcode.reset_column_information
+      end
+
+      def test_copy_table_with_composite_primary_keys
+        connection = Barcode.connection
+        connection.create_table(:barcodes, primary_key: ["region", "code"], force: true) do |t|
+          t.string :region
+          t.string :code
+          t.text :other_attr
+        end
+        region = "US"
+        code = "214fe0c2-dd47-46df-b53b-66090b3c1d40"
+        Barcode.create!(region: region, code: code, other_attr: "xxx")
+
+        connection.remove_column("barcodes", "other_attr")
+
+        assert_equal ["region", "code"], connection.primary_keys("barcodes")
+
+        barcode = Barcode.first
+        assert_equal region, barcode.region
+        assert_equal code, barcode.code
+      ensure
+        Barcode.reset_column_information
+      end
+
+      def test_custom_primary_key_in_create_table
+        connection = Barcode.connection
+        connection.create_table :barcodes, id: false, force: true do |t|
+          t.primary_key :id, :string
+        end
+
+        assert_equal "id", connection.primary_key("barcodes")
+
+        custom_pk = Barcode.columns_hash["id"]
+
+        assert_equal :string, custom_pk.type
+        assert_not custom_pk.null
+      ensure
+        Barcode.reset_column_information
+      end
+
+      def test_custom_primary_key_in_change_table
+        connection = Barcode.connection
+        connection.create_table :barcodes, id: false, force: true do |t|
+          t.integer :dummy
+        end
+        connection.change_table :barcodes do |t|
+          t.primary_key :id, :string
         end
+
+        assert_equal "id", connection.primary_key("barcodes")
+
+        custom_pk = Barcode.columns_hash["id"]
+
+        assert_equal :string, custom_pk.type
+        assert_not custom_pk.null
+      ensure
+        Barcode.reset_column_information
+      end
+
+      def test_add_column_with_custom_primary_key
+        connection = Barcode.connection
+        connection.create_table :barcodes, id: false, force: true do |t|
+          t.integer :dummy
+        end
+        connection.add_column :barcodes, :id, :string, primary_key: true
+
+        assert_equal "id", connection.primary_key("barcodes")
+
+        custom_pk = Barcode.columns_hash["id"]
+
+        assert_equal :string, custom_pk.type
+        assert_not custom_pk.null
+      ensure
+        Barcode.reset_column_information
+      end
+
+      def test_remove_column_preserves_partial_indexes
+        connection = Barcode.connection
+        connection.create_table :barcodes, force: true do |t|
+          t.string :code
+          t.string :region
+          t.boolean :bool_attr
+
+          t.index :code, unique: true, where: :bool_attr, name: "partial"
+        end
+        connection.remove_column :barcodes, :region
+
+        index = connection.indexes("barcodes").find { |idx| idx.name == "partial" }
+        assert_equal "bool_attr", index.where
+      ensure
+        Barcode.reset_column_information
       end
 
       def test_supports_extensions
-        assert_not @conn.supports_extensions?, 'does not support extensions'
+        assert_not @conn.supports_extensions?, "does not support extensions"
       end
 
       def test_respond_to_enable_extension
@@ -402,15 +484,15 @@ module ActiveRecord
 
       def test_statement_closed
         db = ::SQLite3::Database.new(ActiveRecord::Base.
-                                   configurations['arunit']['database'])
+                                   configurations["arunit"]["database"])
         statement = ::SQLite3::Statement.new(db,
-                                           'CREATE TABLE statement_test (number integer not null)')
-        statement.stub(:step, ->{ raise ::SQLite3::BusyException.new('busy') }) do
+                                           "CREATE TABLE statement_test (number integer not null)")
+        statement.stub(:step, -> { raise ::SQLite3::BusyException.new("busy") }) do
           assert_called(statement, :columns, returns: []) do
             assert_called(statement, :close) do
               ::SQLite3::Statement.stub(:new, statement) do
                 assert_raises ActiveRecord::StatementInvalid do
-                  @conn.exec_query 'select * from statement_test'
+                  @conn.exec_query "select * from statement_test"
                 end
               end
             end
@@ -420,22 +502,22 @@ module ActiveRecord
 
       private
 
-      def assert_logged logs
-        subscriber = SQLSubscriber.new
-        subscription = ActiveSupport::Notifications.subscribe('sql.active_record', subscriber)
-        yield
-        assert_equal logs, subscriber.logged
-      ensure
-        ActiveSupport::Notifications.unsubscribe(subscription)
-      end
+        def assert_logged(logs)
+          subscriber = SQLSubscriber.new
+          subscription = ActiveSupport::Notifications.subscribe("sql.active_record", subscriber)
+          yield
+          assert_equal logs, subscriber.logged
+        ensure
+          ActiveSupport::Notifications.unsubscribe(subscription)
+        end
 
-      def with_example_table(definition = nil, table_name = 'ex', &block)
-        definition ||= <<-SQL
-          id integer PRIMARY KEY AUTOINCREMENT,
-          number integer
-        SQL
-        super(@conn, table_name, definition, &block)
-      end
+        def with_example_table(definition = nil, table_name = "ex", &block)
+          definition ||= <<-SQL
+            id integer PRIMARY KEY AUTOINCREMENT,
+            number integer
+          SQL
+          super(@conn, table_name, definition, &block)
+        end
     end
   end
 end
diff --git a/activerecord/test/cases/adapters/sqlite3/sqlite3_create_folder_test.rb b/activerecord/test/cases/adapters/sqlite3/sqlite3_create_folder_test.rb
index 9b675b804b..d70486605f 100644
--- a/activerecord/test/cases/adapters/sqlite3/sqlite3_create_folder_test.rb
+++ b/activerecord/test/cases/adapters/sqlite3/sqlite3_create_folder_test.rb
@@ -1,5 +1,7 @@
+# frozen_string_literal: true
+
 require "cases/helper"
-require 'models/owner'
+require "models/owner"
 
 module ActiveRecord
   module ConnectionAdapters
@@ -8,12 +10,12 @@ module ActiveRecord
         Dir.mktmpdir do |dir|
           begin
             dir = Pathname.new(dir)
-            @conn = Base.sqlite3_connection :database => dir.join("db/foo.sqlite3"),
-                                 :adapter => 'sqlite3',
-                                 :timeout => 100
+            @conn = Base.sqlite3_connection database: dir.join("db/foo.sqlite3"),
+                                 adapter: "sqlite3",
+                                 timeout: 100
 
-            assert Dir.exist? dir.join('db')
-            assert File.exist? dir.join('db/foo.sqlite3')
+            assert Dir.exist? dir.join("db")
+            assert File.exist? dir.join("db/foo.sqlite3")
           ensure
             @conn.disconnect! if @conn
           end
diff --git a/activerecord/test/cases/adapters/sqlite3/statement_pool_test.rb b/activerecord/test/cases/adapters/sqlite3/statement_pool_test.rb
index 24cc6875ab..61002435a4 100644
--- a/activerecord/test/cases/adapters/sqlite3/statement_pool_test.rb
+++ b/activerecord/test/cases/adapters/sqlite3/statement_pool_test.rb
@@ -1,20 +1,21 @@
-require 'cases/helper'
+# frozen_string_literal: true
+
+require "cases/helper"
 
 class SQLite3StatementPoolTest < ActiveRecord::SQLite3TestCase
   if Process.respond_to?(:fork)
     def test_cache_is_per_pid
-
       cache = ActiveRecord::ConnectionAdapters::SQLite3Adapter::StatementPool.new(10)
-      cache['foo'] = 'bar'
-      assert_equal 'bar', cache['foo']
+      cache["foo"] = "bar"
+      assert_equal "bar", cache["foo"]
 
       pid = fork {
-        lookup = cache['foo'];
+        lookup = cache["foo"]
         exit!(!lookup)
       }
 
       Process.waitpid pid
-      assert $?.success?, 'process should exit successfully'
+      assert $?.success?, "process should exit successfully"
     end
   end
 end
diff --git a/activerecord/test/cases/aggregations_test.rb b/activerecord/test/cases/aggregations_test.rb
index 8a728902a8..fbdf2ada4b 100644
--- a/activerecord/test/cases/aggregations_test.rb
+++ b/activerecord/test/cases/aggregations_test.rb
@@ -1,5 +1,7 @@
+# frozen_string_literal: true
+
 require "cases/helper"
-require 'models/customer'
+require "models/customer"
 
 class AggregationsTest < ActiveRecord::TestCase
   fixtures :customers
@@ -25,7 +27,7 @@ class AggregationsTest < ActiveRecord::TestCase
 
   def test_immutable_value_objects
     customers(:david).balance = Money.new(100)
-    assert_raise(RuntimeError) { customers(:david).balance.instance_eval { @amount = 20 } }
+    assert_raise(frozen_error_class) { customers(:david).balance.instance_eval { @amount = 20 } }
   end
 
   def test_inferred_mapping
@@ -51,17 +53,17 @@ class AggregationsTest < ActiveRecord::TestCase
 
     Customer.update_all("gps_location = '24x113'")
     customers(:david).reload
-    assert_equal '24x113', customers(:david)['gps_location']
+    assert_equal "24x113", customers(:david)["gps_location"]
 
-    assert_equal GpsLocation.new('24x113'), customers(:david).gps_location
+    assert_equal GpsLocation.new("24x113"), customers(:david).gps_location
   end
 
   def test_gps_equality
-    assert_equal GpsLocation.new('39x110'), GpsLocation.new('39x110')
+    assert_equal GpsLocation.new("39x110"), GpsLocation.new("39x110")
   end
 
   def test_gps_inequality
-    assert_not_equal GpsLocation.new('39x110'), GpsLocation.new('39x111')
+    assert_not_equal GpsLocation.new("39x110"), GpsLocation.new("39x111")
   end
 
   def test_allow_nil_gps_is_nil
@@ -102,7 +104,7 @@ class AggregationsTest < ActiveRecord::TestCase
   end
 
   def test_nil_assignment_results_in_nil
-    customers(:david).gps_location = GpsLocation.new('39x111')
+    customers(:david).gps_location = GpsLocation.new("39x111")
     assert_not_nil customers(:david).gps_location
     customers(:david).gps_location = nil
     assert_nil customers(:david).gps_location
@@ -129,13 +131,13 @@ class AggregationsTest < ActiveRecord::TestCase
   end
 
   def test_custom_constructor
-    assert_equal 'Barney GUMBLE', customers(:barney).fullname.to_s
+    assert_equal "Barney GUMBLE", customers(:barney).fullname.to_s
     assert_kind_of Fullname, customers(:barney).fullname
   end
 
   def test_custom_converter
-    customers(:barney).fullname = 'Barnoit Gumbleau'
-    assert_equal 'Barnoit GUMBLEAU', customers(:barney).fullname.to_s
+    customers(:barney).fullname = "Barnoit Gumbleau"
+    assert_equal "Barnoit GUMBLEAU", customers(:barney).fullname.to_s
     assert_kind_of Fullname, customers(:barney).fullname
   end
 
@@ -143,17 +145,22 @@ class AggregationsTest < ActiveRecord::TestCase
     customers(:barney).fullname = { first: "Barney", last: "Stinson" }
     assert_equal "Barney STINSON", customers(:barney).name
   end
+
+  def test_assigning_hash_without_custom_converter
+    customers(:barney).fullname_no_converter = { first: "Barney", last: "Stinson" }
+    assert_equal({ first: "Barney", last: "Stinson" }.to_s, customers(:barney).name)
+  end
 end
 
 class OverridingAggregationsTest < ActiveRecord::TestCase
   class DifferentName; end
 
   class Person < ActiveRecord::Base
-    composed_of :composed_of, :mapping => %w(person_first_name first_name)
+    composed_of :composed_of, mapping: %w(person_first_name first_name)
   end
 
   class DifferentPerson < Person
-    composed_of :composed_of, :class_name => 'DifferentName', :mapping => %w(different_person_first_name first_name)
+    composed_of :composed_of, class_name: "DifferentName", mapping: %w(different_person_first_name first_name)
   end
 
   def test_composed_of_aggregation_redefinition_reflections_should_differ_and_not_inherited
diff --git a/activerecord/test/cases/ar_schema_test.rb b/activerecord/test/cases/ar_schema_test.rb
index 9c99689c1e..83974f327e 100644
--- a/activerecord/test/cases/ar_schema_test.rb
+++ b/activerecord/test/cases/ar_schema_test.rb
@@ -1,130 +1,145 @@
+# frozen_string_literal: true
+
 require "cases/helper"
 
-if ActiveRecord::Base.connection.supports_migrations?
+class ActiveRecordSchemaTest < ActiveRecord::TestCase
+  self.use_transactional_tests = false
 
-  class ActiveRecordSchemaTest < ActiveRecord::TestCase
-    self.use_transactional_tests = false
+  setup do
+    @original_verbose = ActiveRecord::Migration.verbose
+    ActiveRecord::Migration.verbose = false
+    @connection = ActiveRecord::Base.connection
+    ActiveRecord::SchemaMigration.drop_table
+  end
 
-    setup do
-      @original_verbose = ActiveRecord::Migration.verbose
-      ActiveRecord::Migration.verbose = false
-      @connection = ActiveRecord::Base.connection
-      ActiveRecord::SchemaMigration.drop_table
-    end
+  teardown do
+    @connection.drop_table :fruits rescue nil
+    @connection.drop_table :nep_fruits rescue nil
+    @connection.drop_table :nep_schema_migrations rescue nil
+    @connection.drop_table :has_timestamps rescue nil
+    @connection.drop_table :multiple_indexes rescue nil
+    ActiveRecord::SchemaMigration.delete_all rescue nil
+    ActiveRecord::Migration.verbose = @original_verbose
+  end
 
-    teardown do
-      @connection.drop_table :fruits rescue nil
-      @connection.drop_table :nep_fruits rescue nil
-      @connection.drop_table :nep_schema_migrations rescue nil
-      @connection.drop_table :has_timestamps rescue nil
-      ActiveRecord::SchemaMigration.delete_all rescue nil
-      ActiveRecord::Migration.verbose = @original_verbose
-    end
+  def test_has_primary_key
+    old_primary_key_prefix_type = ActiveRecord::Base.primary_key_prefix_type
+    ActiveRecord::Base.primary_key_prefix_type = :table_name_with_underscore
+    assert_equal "version", ActiveRecord::SchemaMigration.primary_key
 
-    def test_has_primary_key
-      old_primary_key_prefix_type = ActiveRecord::Base.primary_key_prefix_type
-      ActiveRecord::Base.primary_key_prefix_type = :table_name_with_underscore
-      assert_equal "version", ActiveRecord::SchemaMigration.primary_key
+    ActiveRecord::SchemaMigration.create_table
+    assert_difference "ActiveRecord::SchemaMigration.count", 1 do
+      ActiveRecord::SchemaMigration.create version: 12
+    end
+  ensure
+    ActiveRecord::SchemaMigration.drop_table
+    ActiveRecord::Base.primary_key_prefix_type = old_primary_key_prefix_type
+  end
 
-      ActiveRecord::SchemaMigration.create_table
-      assert_difference "ActiveRecord::SchemaMigration.count", 1 do
-        ActiveRecord::SchemaMigration.create version: 12
+  def test_schema_define
+    ActiveRecord::Schema.define(version: 7) do
+      create_table :fruits do |t|
+        t.column :color, :string
+        t.column :fruit_size, :string  # NOTE: "size" is reserved in Oracle
+        t.column :texture, :string
+        t.column :flavor, :string
       end
-    ensure
-      ActiveRecord::SchemaMigration.drop_table
-      ActiveRecord::Base.primary_key_prefix_type = old_primary_key_prefix_type
     end
 
-    def test_schema_define
-      ActiveRecord::Schema.define(:version => 7) do
-        create_table :fruits do |t|
-          t.column :color, :string
-          t.column :fruit_size, :string  # NOTE: "size" is reserved in Oracle
-          t.column :texture, :string
-          t.column :flavor, :string
-        end
-      end
+    assert_nothing_raised { @connection.select_all "SELECT * FROM fruits" }
+    assert_nothing_raised { @connection.select_all "SELECT * FROM schema_migrations" }
+    assert_equal 7, ActiveRecord::Migrator::current_version
+  end
 
-      assert_nothing_raised { @connection.select_all "SELECT * FROM fruits" }
-      assert_nothing_raised { @connection.select_all "SELECT * FROM schema_migrations" }
-      assert_equal 7, ActiveRecord::Migrator::current_version
+  def test_schema_define_w_table_name_prefix
+    table_name = ActiveRecord::SchemaMigration.table_name
+    old_table_name_prefix = ActiveRecord::Base.table_name_prefix
+    ActiveRecord::Base.table_name_prefix = "nep_"
+    ActiveRecord::SchemaMigration.table_name = "nep_#{table_name}"
+    ActiveRecord::Schema.define(version: 7) do
+      create_table :fruits do |t|
+        t.column :color, :string
+        t.column :fruit_size, :string  # NOTE: "size" is reserved in Oracle
+        t.column :texture, :string
+        t.column :flavor, :string
+      end
     end
+    assert_equal 7, ActiveRecord::Migrator::current_version
+  ensure
+    ActiveRecord::Base.table_name_prefix = old_table_name_prefix
+    ActiveRecord::SchemaMigration.table_name = table_name
+  end
 
-    def test_schema_define_w_table_name_prefix
-      table_name = ActiveRecord::SchemaMigration.table_name
-      old_table_name_prefix = ActiveRecord::Base.table_name_prefix
-      ActiveRecord::Base.table_name_prefix  = "nep_"
-      ActiveRecord::SchemaMigration.table_name = "nep_#{table_name}"
-      ActiveRecord::Schema.define(:version => 7) do
-        create_table :fruits do |t|
-          t.column :color, :string
-          t.column :fruit_size, :string  # NOTE: "size" is reserved in Oracle
-          t.column :texture, :string
-          t.column :flavor, :string
+  def test_schema_raises_an_error_for_invalid_column_type
+    assert_raise NoMethodError do
+      ActiveRecord::Schema.define(version: 8) do
+        create_table :vegetables do |t|
+          t.unknown :color
         end
       end
-      assert_equal 7, ActiveRecord::Migrator::current_version
-    ensure
-      ActiveRecord::Base.table_name_prefix  = old_table_name_prefix
-      ActiveRecord::SchemaMigration.table_name = table_name
     end
+  end
 
-    def test_schema_raises_an_error_for_invalid_column_type
-      assert_raise NoMethodError do
-        ActiveRecord::Schema.define(:version => 8) do
-          create_table :vegetables do |t|
-            t.unknown :color
-          end
-        end
-      end
+  def test_schema_subclass
+    Class.new(ActiveRecord::Schema).define(version: 9) do
+      create_table :fruits
     end
+    assert_nothing_raised { @connection.select_all "SELECT * FROM fruits" }
+  end
+
+  def test_normalize_version
+    assert_equal "118", ActiveRecord::SchemaMigration.normalize_migration_number("0000118")
+    assert_equal "002", ActiveRecord::SchemaMigration.normalize_migration_number("2")
+    assert_equal "017", ActiveRecord::SchemaMigration.normalize_migration_number("0017")
+    assert_equal "20131219224947", ActiveRecord::SchemaMigration.normalize_migration_number("20131219224947")
+  end
 
-    def test_schema_subclass
-      Class.new(ActiveRecord::Schema).define(:version => 9) do
-        create_table :fruits
+  def test_schema_load_with_multiple_indexes_for_column_of_different_names
+    ActiveRecord::Schema.define do
+      create_table :multiple_indexes do |t|
+        t.string "foo"
+        t.index ["foo"], name: "multiple_indexes_foo_1"
+        t.index ["foo"], name: "multiple_indexes_foo_2"
       end
-      assert_nothing_raised { @connection.select_all "SELECT * FROM fruits" }
     end
 
-    def test_normalize_version
-      assert_equal "118", ActiveRecord::SchemaMigration.normalize_migration_number("0000118")
-      assert_equal "002", ActiveRecord::SchemaMigration.normalize_migration_number("2")
-      assert_equal "017", ActiveRecord::SchemaMigration.normalize_migration_number("0017")
-      assert_equal "20131219224947", ActiveRecord::SchemaMigration.normalize_migration_number("20131219224947")
-    end
+    indexes = @connection.indexes("multiple_indexes")
 
-    def test_timestamps_without_null_set_null_to_false_on_create_table
-      ActiveRecord::Schema.define do
-        create_table :has_timestamps do |t|
-          t.timestamps
-        end
-      end
+    assert_equal 2, indexes.length
+    assert_equal ["multiple_indexes_foo_1", "multiple_indexes_foo_2"], indexes.collect(&:name).sort
+  end
 
-      assert !@connection.columns(:has_timestamps).find { |c| c.name == 'created_at' }.null
-      assert !@connection.columns(:has_timestamps).find { |c| c.name == 'updated_at' }.null
+  def test_timestamps_without_null_set_null_to_false_on_create_table
+    ActiveRecord::Schema.define do
+      create_table :has_timestamps do |t|
+        t.timestamps
+      end
     end
 
-    def test_timestamps_without_null_set_null_to_false_on_change_table
-      ActiveRecord::Schema.define do
-        create_table :has_timestamps
+    assert !@connection.columns(:has_timestamps).find { |c| c.name == "created_at" }.null
+    assert !@connection.columns(:has_timestamps).find { |c| c.name == "updated_at" }.null
+  end
 
-        change_table :has_timestamps do |t|
-          t.timestamps default: Time.now
-        end
-      end
+  def test_timestamps_without_null_set_null_to_false_on_change_table
+    ActiveRecord::Schema.define do
+      create_table :has_timestamps
 
-      assert !@connection.columns(:has_timestamps).find { |c| c.name == 'created_at' }.null
-      assert !@connection.columns(:has_timestamps).find { |c| c.name == 'updated_at' }.null
+      change_table :has_timestamps do |t|
+        t.timestamps default: Time.now
+      end
     end
 
-    def test_timestamps_without_null_set_null_to_false_on_add_timestamps
-      ActiveRecord::Schema.define do
-        create_table :has_timestamps
-        add_timestamps :has_timestamps, default: Time.now
-      end
+    assert !@connection.columns(:has_timestamps).find { |c| c.name == "created_at" }.null
+    assert !@connection.columns(:has_timestamps).find { |c| c.name == "updated_at" }.null
+  end
 
-      assert !@connection.columns(:has_timestamps).find { |c| c.name == 'created_at' }.null
-      assert !@connection.columns(:has_timestamps).find { |c| c.name == 'updated_at' }.null
+  def test_timestamps_without_null_set_null_to_false_on_add_timestamps
+    ActiveRecord::Schema.define do
+      create_table :has_timestamps
+      add_timestamps :has_timestamps, default: Time.now
     end
+
+    assert !@connection.columns(:has_timestamps).find { |c| c.name == "created_at" }.null
+    assert !@connection.columns(:has_timestamps).find { |c| c.name == "updated_at" }.null
   end
 end
diff --git a/activerecord/test/cases/associations/association_scope_test.rb b/activerecord/test/cases/associations/association_scope_test.rb
deleted file mode 100644
index 472e270f8c..0000000000
--- a/activerecord/test/cases/associations/association_scope_test.rb
+++ /dev/null
@@ -1,16 +0,0 @@
-require 'cases/helper'
-require 'models/post'
-require 'models/author'
-
-module ActiveRecord
-  module Associations
-    class AssociationScopeTest < ActiveRecord::TestCase
-      test 'does not duplicate conditions' do
-        scope = AssociationScope.scope(Author.new.association(:welcome_posts),
-                                        Author.connection)
-        binds = scope.where_clause.binds.map(&:value)
-        assert_equal binds.uniq, binds
-      end
-    end
-  end
-end
diff --git a/activerecord/test/cases/associations/belongs_to_associations_test.rb b/activerecord/test/cases/associations/belongs_to_associations_test.rb
index 9dadd114a1..0f7a249bf3 100644
--- a/activerecord/test/cases/associations/belongs_to_associations_test.rb
+++ b/activerecord/test/cases/associations/belongs_to_associations_test.rb
@@ -1,28 +1,30 @@
-require 'cases/helper'
-require 'models/developer'
-require 'models/project'
-require 'models/company'
-require 'models/topic'
-require 'models/reply'
-require 'models/computer'
-require 'models/post'
-require 'models/author'
-require 'models/tag'
-require 'models/tagging'
-require 'models/comment'
-require 'models/sponsor'
-require 'models/member'
-require 'models/essay'
-require 'models/toy'
-require 'models/invoice'
-require 'models/line_item'
-require 'models/column'
-require 'models/record'
-require 'models/admin'
-require 'models/admin/user'
-require 'models/ship'
-require 'models/treasure'
-require 'models/parrot'
+# frozen_string_literal: true
+
+require "cases/helper"
+require "models/developer"
+require "models/project"
+require "models/company"
+require "models/topic"
+require "models/reply"
+require "models/computer"
+require "models/post"
+require "models/author"
+require "models/tag"
+require "models/tagging"
+require "models/comment"
+require "models/sponsor"
+require "models/member"
+require "models/essay"
+require "models/toy"
+require "models/invoice"
+require "models/line_item"
+require "models/column"
+require "models/record"
+require "models/admin"
+require "models/admin/user"
+require "models/ship"
+require "models/treasure"
+require "models/parrot"
 
 class BelongsToAssociationsTest < ActiveRecord::TestCase
   fixtures :accounts, :companies, :developers, :projects, :topics,
@@ -43,11 +45,11 @@ class BelongsToAssociationsTest < ActiveRecord::TestCase
     ActiveRecord::SQLCounter.clear_log
     Client.find(3).firm
   ensure
-    assert ActiveRecord::SQLCounter.log_all.all? { |sql| /order by/i !~ sql }, 'ORDER BY was used in the query'
+    assert ActiveRecord::SQLCounter.log_all.all? { |sql| /order by/i !~ sql }, "ORDER BY was used in the query"
   end
 
   def test_belongs_to_with_primary_key
-    client = Client.create(:name => "Primary key client", :firm_name => companies(:first_firm).name)
+    client = Client.create(name: "Primary key client", firm_name: companies(:first_firm).name)
     assert_equal companies(:first_firm).name, client.firm_with_primary_key.name
   end
 
@@ -94,7 +96,7 @@ class BelongsToAssociationsTest < ActiveRecord::TestCase
 
     account = model.new
     assert_not account.valid?
-    assert_equal [{error: :blank}], account.errors.details[:company]
+    assert_equal [{ error: :blank }], account.errors.details[:company]
   ensure
     ActiveRecord::Base.belongs_to_required_by_default = original_value
   end
@@ -111,30 +113,68 @@ class BelongsToAssociationsTest < ActiveRecord::TestCase
 
     account = model.new
     assert_not account.valid?
-    assert_equal [{error: :blank}], account.errors.details[:company]
+    assert_equal [{ error: :blank }], account.errors.details[:company]
   ensure
     ActiveRecord::Base.belongs_to_required_by_default = original_value
   end
 
+  def test_default
+    david = developers(:david)
+    jamis = developers(:jamis)
+
+    model = Class.new(ActiveRecord::Base) do
+      self.table_name = "ships"
+      def self.name; "Temp"; end
+      belongs_to :developer, default: -> { david }
+    end
+
+    ship = model.create!
+    assert_equal david, ship.developer
+
+    ship = model.create!(developer: jamis)
+    assert_equal jamis, ship.developer
+
+    ship.update!(developer: nil)
+    assert_equal david, ship.developer
+  end
+
+  def test_default_with_lambda
+    model = Class.new(ActiveRecord::Base) do
+      self.table_name = "ships"
+      def self.name; "Temp"; end
+      belongs_to :developer, default: -> { default_developer }
+
+      def default_developer
+        Developer.first
+      end
+    end
+
+    ship = model.create!
+    assert_equal developers(:david), ship.developer
+
+    ship = model.create!(developer: developers(:jamis))
+    assert_equal developers(:jamis), ship.developer
+  end
+
   def test_default_scope_on_relations_is_not_cached
     counter = 0
 
     comments = Class.new(ActiveRecord::Base) {
-      self.table_name = 'comments'
-      self.inheritance_column = 'not_there'
+      self.table_name = "comments"
+      self.inheritance_column = "not_there"
 
       posts = Class.new(ActiveRecord::Base) {
-        self.table_name = 'posts'
-        self.inheritance_column = 'not_there'
+        self.table_name = "posts"
+        self.inheritance_column = "not_there"
 
         default_scope -> {
           counter += 1
-          where("id = :inc", :inc => counter)
+          where("id = :inc", inc: counter)
         }
 
-        has_many :comments, :anonymous_class => comments
+        has_many :comments, anonymous_class: comments
       }
-      belongs_to :post, :anonymous_class => posts, :inverse_of => false
+      belongs_to :post, anonymous_class: posts, inverse_of: false
     }
 
     assert_equal 0, counter
@@ -166,7 +206,7 @@ class BelongsToAssociationsTest < ActiveRecord::TestCase
     Admin.const_set "Region", Class.new(ActiveRecord::Base)
 
     e = assert_raise(ActiveRecord::AssociationTypeMismatch) {
-      Admin::RegionalUser.new(region: 'wrong value')
+      Admin::RegionalUser.new(region: "wrong value")
     }
     assert_match(/^Region\([^)]+\) expected, got "wrong value" which is an instance of String\([^)]+\)$/, e.message)
   ensure
@@ -177,6 +217,8 @@ class BelongsToAssociationsTest < ActiveRecord::TestCase
       remove_column :admin_users, :region_id if column_exists?(:admin_users, :region_id)
       drop_table :admin_regions, if_exists: true
     end
+
+    Admin::User.reset_column_information
   end
 
   def test_natural_assignment
@@ -203,14 +245,14 @@ class BelongsToAssociationsTest < ActiveRecord::TestCase
   def test_eager_loading_with_primary_key
     Firm.create("name" => "Apple")
     Client.create("name" => "Citibank", :firm_name => "Apple")
-    citibank_result = Client.all.merge!(:where => {:name => "Citibank"}, :includes => :firm_with_primary_key).first
+    citibank_result = Client.all.merge!(where: { name: "Citibank" }, includes: :firm_with_primary_key).first
     assert citibank_result.association(:firm_with_primary_key).loaded?
   end
 
   def test_eager_loading_with_primary_key_as_symbol
     Firm.create("name" => "Apple")
     Client.create("name" => "Citibank", :firm_name => "Apple")
-    citibank_result = Client.all.merge!(:where => {:name => "Citibank"}, :includes => :firm_with_primary_key_symbols).first
+    citibank_result = Client.all.merge!(where: { name: "Citibank" }, includes: :firm_with_primary_key_symbols).first
     assert citibank_result.association(:firm_with_primary_key_symbols).loaded?
   end
 
@@ -224,7 +266,7 @@ class BelongsToAssociationsTest < ActiveRecord::TestCase
   end
 
   def test_creating_the_belonging_object_with_primary_key
-    client = Client.create(:name => "Primary key client")
+    client = Client.create(name: "Primary key client")
     apple  = client.create_firm_with_primary_key("name" => "Apple")
     assert_equal apple, client.firm_with_primary_key
     client.save
@@ -247,36 +289,36 @@ class BelongsToAssociationsTest < ActiveRecord::TestCase
 
   def test_building_the_belonging_object_with_explicit_sti_base_class
     account = Account.new
-    company = account.build_firm(:type => "Company")
+    company = account.build_firm(type: "Company")
     assert_kind_of Company, company, "Expected #{company.class} to be a Company"
   end
 
   def test_building_the_belonging_object_with_sti_subclass
     account = Account.new
-    company = account.build_firm(:type => "Firm")
+    company = account.build_firm(type: "Firm")
     assert_kind_of Firm, company, "Expected #{company.class} to be a Firm"
   end
 
   def test_building_the_belonging_object_with_an_invalid_type
     account = Account.new
-    assert_raise(ActiveRecord::SubclassNotFound) { account.build_firm(:type => "InvalidType") }
+    assert_raise(ActiveRecord::SubclassNotFound) { account.build_firm(type: "InvalidType") }
   end
 
   def test_building_the_belonging_object_with_an_unrelated_type
     account = Account.new
-    assert_raise(ActiveRecord::SubclassNotFound) { account.build_firm(:type => "Account") }
+    assert_raise(ActiveRecord::SubclassNotFound) { account.build_firm(type: "Account") }
   end
 
   def test_building_the_belonging_object_with_primary_key
-    client = Client.create(:name => "Primary key client")
+    client = Client.create(name: "Primary key client")
     apple  = client.build_firm_with_primary_key("name" => "Apple")
     client.save
     assert_equal apple.name, client.firm_name
   end
 
   def test_create!
-    client  = Client.create!(:name => "Jimmy")
-    account = client.create_account!(:credit_limit => 10)
+    client  = Client.create!(name: "Jimmy")
+    account = client.create_account!(credit_limit: 10)
     assert_equal account, client.account
     assert account.persisted?
     client.save
@@ -285,12 +327,22 @@ class BelongsToAssociationsTest < ActiveRecord::TestCase
   end
 
   def test_failing_create!
-    client  = Client.create!(:name => "Jimmy")
+    client = Client.create!(name: "Jimmy")
     assert_raise(ActiveRecord::RecordInvalid) { client.create_account! }
     assert_not_nil client.account
     assert client.account.new_record?
   end
 
+  def test_reloading_the_belonging_object
+    odegy_account = accounts(:odegy_account)
+
+    assert_equal "Odegy", odegy_account.firm.name
+    Company.where(id: odegy_account.firm_id).update_all(name: "ODEGY")
+    assert_equal "Odegy", odegy_account.firm.name
+
+    assert_equal "ODEGY", odegy_account.reload_firm.name
+  end
+
   def test_natural_assignment_to_nil
     client = Client.find(3)
     client.firm = nil
@@ -301,7 +353,7 @@ class BelongsToAssociationsTest < ActiveRecord::TestCase
   end
 
   def test_natural_assignment_to_nil_with_primary_key
-    client = Client.create(:name => "Primary key client", :firm_name => companies(:first_firm).name)
+    client = Client.create(name: "Primary key client", firm_name: companies(:first_firm).name)
     client.firm_with_primary_key = nil
     client.save
     client.association(:firm_with_primary_key).reload
@@ -325,19 +377,18 @@ class BelongsToAssociationsTest < ActiveRecord::TestCase
     sponsor.association(:sponsorable).reload
     assert_nil sponsor.sponsorable
 
-    sponsor.sponsorable_type = '' # the column doesn't have to be declared NOT NULL
+    sponsor.sponsorable_type = "" # the column doesn't have to be declared NOT NULL
     assert_nil sponsor.association(:sponsorable).send(:klass)
     sponsor.association(:sponsorable).reload
     assert_nil sponsor.sponsorable
 
-    sponsor.sponsorable = Member.new :name => "Bert"
+    sponsor.sponsorable = Member.new name: "Bert"
     assert_equal Member, sponsor.association(:sponsorable).send(:klass)
-    assert_equal "members", sponsor.association(:sponsorable).aliased_table_name
   end
 
   def test_with_polymorphic_and_condition
     sponsor = Sponsor.create
-    member = Member.create :name => "Bert"
+    member = Member.create name: "Bert"
     sponsor.sponsorable = member
 
     assert_equal member, sponsor.sponsorable
@@ -346,16 +397,16 @@ class BelongsToAssociationsTest < ActiveRecord::TestCase
 
   def test_with_select
     assert_equal 1, Company.find(2).firm_with_select.attributes.size
-    assert_equal 1, Company.all.merge!(:includes => :firm_with_select ).find(2).firm_with_select.attributes.size
+    assert_equal 1, Company.all.merge!(includes: :firm_with_select).find(2).firm_with_select.attributes.size
   end
 
   def test_belongs_to_without_counter_cache_option
     # Ship has a conventionally named `treasures_count` column, but the counter_cache
     # option is not given on the association.
-    ship = Ship.create(name: 'Countless')
+    ship = Ship.create(name: "Countless")
 
     assert_no_difference lambda { ship.reload.treasures_count }, "treasures_count should not be changed unless counter_cache is given on the relation" do
-      treasure = Treasure.new(name: 'Gold', ship: ship)
+      treasure = Treasure.new(name: "Gold", ship: ship)
       treasure.save
     end
 
@@ -461,8 +512,8 @@ class BelongsToAssociationsTest < ActiveRecord::TestCase
   end
 
   def test_belongs_to_counter_after_save
-    topic = Topic.create!(:title => "monday night")
-    topic.replies.create!(:title => "re: monday night", :content => "football")
+    topic = Topic.create!(title: "monday night")
+    topic.replies.create!(title: "re: monday night", content: "football")
     assert_equal 1, Topic.find(topic.id)[:replies_count]
 
     topic.save!
@@ -564,8 +615,8 @@ class BelongsToAssociationsTest < ActiveRecord::TestCase
   end
 
   def test_belongs_to_counter_when_update_columns
-    topic = Topic.create!(:title => "37s")
-    topic.replies.create!(:title => "re: 37s", :content => "rails")
+    topic = Topic.create!(title: "37s")
+    topic.replies.create!(title: "re: 37s", content: "rails")
     assert_equal 1, Topic.find(topic.id)[:replies_count]
 
     topic.update_columns(content: "rails is wonderful")
@@ -600,8 +651,7 @@ class BelongsToAssociationsTest < ActiveRecord::TestCase
 
   def test_new_record_with_foreign_key_but_no_object
     client = Client.new("firm_id" => 1)
-    # sometimes tests on Oracle fail if ORDER BY is not provided therefore add always :order with :first
-    assert_equal Firm.all.merge!(:order => "id").first, client.firm_with_basic_id
+    assert_equal Firm.first, client.firm_with_basic_id
   end
 
   def test_setting_foreign_key_after_nil_target_loaded
@@ -626,16 +676,22 @@ class BelongsToAssociationsTest < ActiveRecord::TestCase
     assert_queries(0) { tagging.super_tag }
   end
 
+  def test_dont_find_target_when_saving_foreign_key_after_stale_association_loaded
+    client = Client.create!(name: "Test client", firm_with_basic_id: Firm.find(1))
+    client.firm_id = Firm.create!(name: "Test firm").id
+    assert_queries(1) { client.save! }
+  end
+
   def test_field_name_same_as_foreign_key
     computer = Computer.find(1)
     assert_not_nil computer.developer, ":foreign key == attribute didn't lock up" # '
   end
 
   def test_counter_cache
-    topic = Topic.create :title => "Zoom-zoom-zoom"
+    topic = Topic.create title: "Zoom-zoom-zoom"
     assert_equal 0, topic[:replies_count]
 
-    reply = Reply.create(:title => "re: zoom", :content => "speedy quick!")
+    reply = Reply.create(title: "re: zoom", content: "speedy quick!")
     reply.topic = topic
 
     assert_equal 1, topic.reload[:replies_count]
@@ -646,10 +702,10 @@ class BelongsToAssociationsTest < ActiveRecord::TestCase
   end
 
   def test_counter_cache_double_destroy
-    topic = Topic.create :title => "Zoom-zoom-zoom"
+    topic = Topic.create title: "Zoom-zoom-zoom"
 
     5.times do
-      topic.replies.create(:title => "re: zoom", :content => "speedy quick!")
+      topic.replies.create(title: "re: zoom", content: "speedy quick!")
     end
 
     assert_equal 5, topic.reload[:replies_count]
@@ -666,10 +722,10 @@ class BelongsToAssociationsTest < ActiveRecord::TestCase
   end
 
   def test_concurrent_counter_cache_double_destroy
-    topic = Topic.create :title => "Zoom-zoom-zoom"
+    topic = Topic.create title: "Zoom-zoom-zoom"
 
     5.times do
-      topic.replies.create(:title => "re: zoom", :content => "speedy quick!")
+      topic.replies.create(title: "re: zoom", content: "speedy quick!")
     end
 
     assert_equal 5, topic.reload[:replies_count]
@@ -687,10 +743,10 @@ class BelongsToAssociationsTest < ActiveRecord::TestCase
   end
 
   def test_custom_counter_cache
-    reply = Reply.create(:title => "re: zoom", :content => "speedy quick!")
+    reply = Reply.create(title: "re: zoom", content: "speedy quick!")
     assert_equal 0, reply[:replies_count]
 
-    silly = SillyReply.create(:title => "gaga", :content => "boo-boo")
+    silly = SillyReply.create(title: "gaga", content: "boo-boo")
     silly.reply = reply
 
     assert_equal 1, reply.reload[:replies_count]
@@ -714,7 +770,7 @@ class BelongsToAssociationsTest < ActiveRecord::TestCase
   def test_association_assignment_sticks
     post = Post.first
 
-    author1, author2 = Author.all.merge!(:limit => 2).to_a
+    author1, author2 = Author.all.merge!(limit: 2).to_a
     assert_not_nil author1
     assert_not_nil author2
 
@@ -767,7 +823,7 @@ class BelongsToAssociationsTest < ActiveRecord::TestCase
   def test_polymorphic_assignment_with_primary_key_foreign_type_field_updating
     # should update when assigning a saved record
     essay = Essay.new
-    writer = Author.create(:name => "David")
+    writer = Author.create(name: "David")
     essay.writer = writer
     assert_equal "Author", essay.writer_type
 
@@ -792,7 +848,7 @@ class BelongsToAssociationsTest < ActiveRecord::TestCase
 
   def test_assignment_updates_foreign_id_field_for_new_and_saved_records
     client = Client.new
-    saved_firm = Firm.create :name => "Saved"
+    saved_firm = Firm.create name: "Saved"
     new_firm = Firm.new
 
     client.firm = saved_firm
@@ -804,7 +860,7 @@ class BelongsToAssociationsTest < ActiveRecord::TestCase
 
   def test_polymorphic_assignment_with_primary_key_updates_foreign_id_field_for_new_and_saved_records
     essay = Essay.new
-    saved_writer = Author.create(:name => "David")
+    saved_writer = Author.create(name: "David")
     new_writer = Author.new
 
     essay.writer = saved_writer
@@ -820,7 +876,7 @@ class BelongsToAssociationsTest < ActiveRecord::TestCase
     assert_nil essay.writer_type
 
     essay.writer_id = 1
-    essay.writer_type = 'Author'
+    essay.writer_type = "Author"
 
     essay.writer = nil
     assert_nil essay.writer_id
@@ -842,14 +898,14 @@ class BelongsToAssociationsTest < ActiveRecord::TestCase
 
     assert_nothing_raised do
       Account.find(@account.id).save!
-      Account.all.merge!(:includes => :firm).find(@account.id).save!
+      Account.all.merge!(includes: :firm).find(@account.id).save!
     end
 
     @account.firm.delete
 
     assert_nothing_raised do
       Account.find(@account.id).save!
-      Account.all.merge!(:includes => :firm).find(@account.id).save!
+      Account.all.merge!(includes: :firm).find(@account.id).save!
     end
   end
 
@@ -870,18 +926,18 @@ class BelongsToAssociationsTest < ActiveRecord::TestCase
 
   def test_belongs_to_invalid_dependent_option_raises_exception
     error = assert_raise ArgumentError do
-      Class.new(Author).belongs_to :special_author_address, :dependent => :nullify
+      Class.new(Author).belongs_to :special_author_address, dependent: :nullify
     end
-    assert_equal error.message, 'The :dependent option must be one of [:destroy, :delete], but is :nullify'
+    assert_equal error.message, "The :dependent option must be one of [:destroy, :delete], but is :nullify"
   end
 
   def test_attributes_are_being_set_when_initialized_from_belongs_to_association_with_where_clause
-    new_firm = accounts(:signals37).build_firm(:name => 'Apple')
+    new_firm = accounts(:signals37).build_firm(name: "Apple")
     assert_equal new_firm.name, "Apple"
   end
 
   def test_attributes_are_set_without_error_when_initialized_from_belongs_to_association_with_array_in_where_clause
-    new_account = Account.where(:credit_limit => [ 50, 60 ]).new
+    new_account = Account.where(credit_limit: [ 50, 60 ]).new
     assert_nil new_account.credit_limit
   end
 
@@ -930,7 +986,7 @@ class BelongsToAssociationsTest < ActiveRecord::TestCase
     assert !proxy.stale_target?
     assert_equal members(:groucho), sponsor.sponsorable
 
-    sponsor.sponsorable_type = 'Firm'
+    sponsor.sponsorable_type = "Firm"
 
     assert proxy.stale_target?
     assert_equal companies(:first_firm), sponsor.sponsorable
@@ -955,7 +1011,7 @@ class BelongsToAssociationsTest < ActiveRecord::TestCase
     comment = comments(:greetings)
 
     assert_difference lambda { post.reload.tags_count }, -1 do
-      assert_difference 'comment.reload.tags_count', +1 do
+      assert_difference "comment.reload.tags_count", +1 do
         tagging.taggable = comment
       end
     end
@@ -1002,46 +1058,46 @@ class BelongsToAssociationsTest < ActiveRecord::TestCase
   end
 
   def test_build_with_block
-    client = Client.create(:name => 'Client Company')
+    client = Client.create(name: "Client Company")
 
-    firm = client.build_firm{ |f| f.name = 'Agency Company' }
-    assert_equal 'Agency Company', firm.name
+    firm = client.build_firm { |f| f.name = "Agency Company" }
+    assert_equal "Agency Company", firm.name
   end
 
   def test_create_with_block
-    client = Client.create(:name => 'Client Company')
+    client = Client.create(name: "Client Company")
 
-    firm = client.create_firm{ |f| f.name = 'Agency Company' }
-    assert_equal 'Agency Company', firm.name
+    firm = client.create_firm { |f| f.name = "Agency Company" }
+    assert_equal "Agency Company", firm.name
   end
 
   def test_create_bang_with_block
-    client = Client.create(:name => 'Client Company')
+    client = Client.create(name: "Client Company")
 
-    firm = client.create_firm!{ |f| f.name = 'Agency Company' }
-    assert_equal 'Agency Company', firm.name
+    firm = client.create_firm! { |f| f.name = "Agency Company" }
+    assert_equal "Agency Company", firm.name
   end
 
   def test_should_set_foreign_key_on_create_association
-    client = Client.create! :name => "fuu"
+    client = Client.create! name: "fuu"
 
-    firm = client.create_firm :name => "baa"
+    firm = client.create_firm name: "baa"
     assert_equal firm.id, client.client_of
   end
 
   def test_should_set_foreign_key_on_create_association!
-    client = Client.create! :name => "fuu"
+    client = Client.create! name: "fuu"
 
-    firm = client.create_firm! :name => "baa"
+    firm = client.create_firm! name: "baa"
     assert_equal firm.id, client.client_of
   end
 
   def test_self_referential_belongs_to_with_counter_cache_assigning_nil
-    comment = Comment.create! :post => posts(:thinking), :body => "fuu"
+    comment = Comment.create! post: posts(:thinking), body: "fuu"
     comment.parent = nil
     comment.save!
 
-    assert_equal nil, comment.reload.parent
+    assert_nil comment.reload.parent
     assert_equal 0, comments(:greetings).reload.children_count
   end
 
@@ -1056,9 +1112,23 @@ class BelongsToAssociationsTest < ActiveRecord::TestCase
     assert_equal 1, parent.reload.children_count
   end
 
+  def test_belongs_to_with_out_of_range_value_assigning
+    model = Class.new(Comment) do
+      def self.name; "Temp"; end
+      validates :post, presence: true
+    end
+
+    comment = model.new
+    comment.post_id = 9223372036854775808 # out of range in the bigint
+
+    assert_nil comment.post
+    assert_not comment.valid?
+    assert_equal [{ error: :blank }], comment.errors.details[:post]
+  end
+
   def test_polymorphic_with_custom_primary_key
     toy = Toy.create!
-    sponsor = Sponsor.create!(:sponsorable => toy)
+    sponsor = Sponsor.create!(sponsorable: toy)
 
     assert_equal toy, sponsor.reload.sponsorable
   end
@@ -1077,7 +1147,7 @@ class BelongsToAssociationsTest < ActiveRecord::TestCase
 
   def test_reflect_the_most_recent_change
     author1, author2 = Author.limit(2)
-    post = Post.new(:title => "foo", :body=> "bar")
+    post = Post.new(title: "foo", body: "bar")
 
     post.author    = author1
     post.author_id = author2.id
@@ -1086,8 +1156,8 @@ class BelongsToAssociationsTest < ActiveRecord::TestCase
     assert_equal post.author_id, author2.id
   end
 
-  test 'dangerous association name raises ArgumentError' do
-    [:errors, 'errors', :save, 'save'].each do |name|
+  test "dangerous association name raises ArgumentError" do
+    [:errors, "errors", :save, "save"].each do |name|
       assert_raises(ArgumentError, "Association #{name} should not be allowed") do
         Class.new(ActiveRecord::Base) do
           belongs_to name
@@ -1096,16 +1166,21 @@ class BelongsToAssociationsTest < ActiveRecord::TestCase
     end
   end
 
-  test 'belongs_to works with model called Record' do
+  test "belongs_to works with model called Record" do
     record = Record.create!
     Column.create! record: record
     assert_equal 1, Column.count
   end
 
-  def test_association_force_reload_with_only_true_is_deprecated
-    client = Client.find(3)
+  def test_multiple_counter_cache_with_after_create_update
+    post = posts(:welcome)
+    parent = comments(:greetings)
 
-    assert_deprecated { client.firm(true) }
+    assert_difference "parent.reload.children_count", +1 do
+      assert_difference "post.reload.comments_count", +1 do
+        CommentWithAfterCreateUpdate.create(body: "foo", post: post, parent: parent)
+      end
+    end
   end
 end
 
diff --git a/activerecord/test/cases/associations/bidirectional_destroy_dependencies_test.rb b/activerecord/test/cases/associations/bidirectional_destroy_dependencies_test.rb
index 2b867965ba..88221b012e 100644
--- a/activerecord/test/cases/associations/bidirectional_destroy_dependencies_test.rb
+++ b/activerecord/test/cases/associations/bidirectional_destroy_dependencies_test.rb
@@ -1,5 +1,7 @@
-require 'cases/helper'
-require 'models/content'
+# frozen_string_literal: true
+
+require "cases/helper"
+require "models/content"
 
 class BidirectionalDestroyDependenciesTest < ActiveRecord::TestCase
   fixtures :content, :content_positions
diff --git a/activerecord/test/cases/associations/callbacks_test.rb b/activerecord/test/cases/associations/callbacks_test.rb
index a4298a25a6..e096cd4a0b 100644
--- a/activerecord/test/cases/associations/callbacks_test.rb
+++ b/activerecord/test/cases/associations/callbacks_test.rb
@@ -1,13 +1,15 @@
+# frozen_string_literal: true
+
 require "cases/helper"
-require 'models/post'
-require 'models/author'
-require 'models/project'
-require 'models/developer'
-require 'models/computer'
-require 'models/company'
+require "models/post"
+require "models/author"
+require "models/project"
+require "models/developer"
+require "models/computer"
+require "models/company"
 
 class AssociationCallbacksTest < ActiveRecord::TestCase
-  fixtures :posts, :authors, :projects, :developers
+  fixtures :posts, :authors, :author_addresses, :projects, :developers
 
   def setup
     @david = authors(:david)
@@ -61,20 +63,20 @@ class AssociationCallbacksTest < ActiveRecord::TestCase
   end
 
   def test_has_many_callbacks_with_create
-    morten = Author.create :name => "Morten"
-    post = morten.posts_with_proc_callbacks.create! :title => "Hello", :body => "How are you doing?"
+    morten = Author.create name: "Morten"
+    post = morten.posts_with_proc_callbacks.create! title: "Hello", body: "How are you doing?"
     assert_equal ["before_adding<new>", "after_adding#{post.id}"], morten.post_log
   end
 
   def test_has_many_callbacks_with_create!
-    morten = Author.create! :name => "Morten"
-    post = morten.posts_with_proc_callbacks.create :title => "Hello", :body => "How are you doing?"
+    morten = Author.create! name: "Morten"
+    post = morten.posts_with_proc_callbacks.create title: "Hello", body: "How are you doing?"
     assert_equal ["before_adding<new>", "after_adding#{post.id}"], morten.post_log
   end
 
   def test_has_many_callbacks_for_save_on_parent
-    jack = Author.new :name => "Jack"
-    jack.posts_with_callbacks.build :title => "Call me back!", :body => "Before you wake up and after you sleep"
+    jack = Author.new name: "Jack"
+    jack.posts_with_callbacks.build title: "Call me back!", body: "Before you wake up and after you sleep"
 
     callback_log = ["before_adding<new>", "after_adding#{jack.posts_with_callbacks.first.id}"]
     assert_equal callback_log, jack.post_log
@@ -84,8 +86,8 @@ class AssociationCallbacksTest < ActiveRecord::TestCase
   end
 
   def test_has_many_callbacks_for_destroy_on_parent
-    firm = Firm.create! :name => "Firm"
-    client = firm.clients.create! :name => "Client"
+    firm = Firm.create! name: "Firm"
+    client = firm.clients.create! name: "Client"
     firm.destroy
 
     assert_equal ["before_remove#{client.id}", "after_remove#{client.id}"], firm.log
@@ -108,14 +110,14 @@ class AssociationCallbacksTest < ActiveRecord::TestCase
     klass = Class.new(Project) do
       def self.name; Project.name; end
       has_and_belongs_to_many :developers_with_callbacks,
-                                :class_name => "Developer",
-                                :before_add => lambda { |o,r|
+                                class_name: "Developer",
+                                before_add: lambda { |o, r|
         dev     = r
         new_dev = r.new_record?
       }
     end
     rec = klass.create!
-    alice = Developer.new(:name => 'alice')
+    alice = Developer.new(name: "alice")
     rec.developers_with_callbacks << alice
     assert_equal alice, dev
     assert_not_nil new_dev
@@ -126,18 +128,17 @@ class AssociationCallbacksTest < ActiveRecord::TestCase
   def test_has_and_belongs_to_many_after_add_called_after_save
     ar = projects(:active_record)
     assert ar.developers_log.empty?
-    alice = Developer.new(:name => 'alice')
+    alice = Developer.new(name: "alice")
     ar.developers_with_callbacks << alice
-    assert_equal"after_adding#{alice.id}", ar.developers_log.last
+    assert_equal "after_adding#{alice.id}", ar.developers_log.last
 
-    bob = ar.developers_with_callbacks.create(:name => 'bob')
+    bob = ar.developers_with_callbacks.create(name: "bob")
     assert_equal "after_adding#{bob.id}", ar.developers_log.last
 
-    ar.developers_with_callbacks.build(:name => 'charlie')
+    ar.developers_with_callbacks.build(name: "charlie")
     assert_equal "after_adding<new>", ar.developers_log.last
   end
 
-
   def test_has_and_belongs_to_many_remove_callback
     david = developers(:david)
     jamis = developers(:jamis)
@@ -160,14 +161,14 @@ class AssociationCallbacksTest < ActiveRecord::TestCase
       activerecord.reload
       assert activerecord.developers_with_callbacks.size == 2
     end
-    activerecord.developers_with_callbacks.flat_map {|d| ["before_removing#{d.id}","after_removing#{d.id}"]}.sort
+    activerecord.developers_with_callbacks.flat_map { |d| ["before_removing#{d.id}", "after_removing#{d.id}"] }.sort
     assert activerecord.developers_with_callbacks.clear
     assert_predicate activerecord.developers_log, :empty?
   end
 
   def test_has_many_and_belongs_to_many_callbacks_for_save_on_parent
-    project = Project.new :name => "Callbacks"
-    project.developers_with_callbacks.build :name => "Jack", :salary => 95000
+    project = Project.new name: "Callbacks"
+    project.developers_with_callbacks.build name: "Jack", salary: 95000
 
     callback_log = ["before_adding<new>", "after_adding<new>"]
     assert_equal callback_log, project.developers_log
@@ -177,14 +178,14 @@ class AssociationCallbacksTest < ActiveRecord::TestCase
   end
 
   def test_dont_add_if_before_callback_raises_exception
-    assert !@david.unchangeable_posts.include?(@authorless)
+    assert_not_includes @david.unchangeable_posts, @authorless
     begin
       @david.unchangeable_posts << @authorless
     rescue Exception
     end
     assert @david.post_log.empty?
-    assert !@david.unchangeable_posts.include?(@authorless)
+    assert_not_includes @david.unchangeable_posts, @authorless
     @david.reload
-    assert !@david.unchangeable_posts.include?(@authorless)
+    assert_not_includes @david.unchangeable_posts, @authorless
   end
 end
diff --git a/activerecord/test/cases/associations/cascaded_eager_loading_test.rb b/activerecord/test/cases/associations/cascaded_eager_loading_test.rb
index 51d8e0523e..e717621928 100644
--- a/activerecord/test/cases/associations/cascaded_eager_loading_test.rb
+++ b/activerecord/test/cases/associations/cascaded_eager_loading_test.rb
@@ -1,56 +1,52 @@
+# frozen_string_literal: true
+
 require "cases/helper"
-require 'models/post'
-require 'models/comment'
-require 'models/author'
-require 'models/categorization'
-require 'models/category'
-require 'models/company'
-require 'models/topic'
-require 'models/reply'
-require 'models/person'
-require 'models/vertex'
-require 'models/edge'
+require "models/post"
+require "models/comment"
+require "models/author"
+require "models/categorization"
+require "models/category"
+require "models/company"
+require "models/topic"
+require "models/reply"
+require "models/person"
+require "models/vertex"
+require "models/edge"
 
 class CascadedEagerLoadingTest < ActiveRecord::TestCase
-  fixtures :authors, :mixins, :companies, :posts, :topics, :accounts, :comments,
+  fixtures :authors, :author_addresses, :mixins, :companies, :posts, :topics, :accounts, :comments,
            :categorizations, :people, :categories, :edges, :vertices
 
   def test_eager_association_loading_with_cascaded_two_levels
-    authors = Author.all.merge!(:includes=>{:posts=>:comments}, :order=>"authors.id").to_a
+    authors = Author.all.merge!(includes: { posts: :comments }, order: "authors.id").to_a
     assert_equal 3, authors.size
     assert_equal 5, authors[0].posts.size
     assert_equal 3, authors[1].posts.size
-    assert_equal 10, authors[0].posts.collect{|post| post.comments.size }.inject(0){|sum,i| sum+i}
+    assert_equal 10, authors[0].posts.collect { |post| post.comments.size }.inject(0) { |sum, i| sum + i }
   end
 
   def test_eager_association_loading_with_cascaded_two_levels_and_one_level
-    authors = Author.all.merge!(:includes=>[{:posts=>:comments}, :categorizations], :order=>"authors.id").to_a
+    authors = Author.all.merge!(includes: [{ posts: :comments }, :categorizations], order: "authors.id").to_a
     assert_equal 3, authors.size
     assert_equal 5, authors[0].posts.size
     assert_equal 3, authors[1].posts.size
-    assert_equal 10, authors[0].posts.collect{|post| post.comments.size }.inject(0){|sum,i| sum+i}
+    assert_equal 10, authors[0].posts.collect { |post| post.comments.size }.inject(0) { |sum, i| sum + i }
     assert_equal 1, authors[0].categorizations.size
     assert_equal 2, authors[1].categorizations.size
   end
 
   def test_eager_association_loading_with_hmt_does_not_table_name_collide_when_joining_associations
-    assert_nothing_raised do
-      Author.joins(:posts).eager_load(:comments).where(:posts => {:tags_count => 1}).to_a
-    end
-    authors = Author.joins(:posts).eager_load(:comments).where(:posts => {:tags_count => 1}).to_a
-    assert_equal 1, assert_no_queries { authors.size }
+    authors = Author.joins(:posts).eager_load(:comments).where(posts: { tags_count: 1 }).to_a
+    assert_equal 3, assert_no_queries { authors.size }
     assert_equal 10, assert_no_queries { authors[0].comments.size }
   end
 
   def test_eager_association_loading_grafts_stashed_associations_to_correct_parent
-    assert_nothing_raised do
-      Person.eager_load(:primary_contact => :primary_contact).where('primary_contacts_people_2.first_name = ?', 'Susan').order('people.id').to_a
-    end
-    assert_equal people(:michael), Person.eager_load(:primary_contact => :primary_contact).where('primary_contacts_people_2.first_name = ?', 'Susan').order('people.id').first
+    assert_equal people(:michael), Person.eager_load(primary_contact: :primary_contact).where("primary_contacts_people_2.first_name = ?", "Susan").order("people.id").first
   end
 
   def test_cascaded_eager_association_loading_with_join_for_count
-    categories = Category.joins(:categorizations).includes([{:posts=>:comments}, :authors])
+    categories = Category.joins(:categorizations).includes([{ posts: :comments }, :authors])
 
     assert_equal 4, categories.count
     assert_equal 4, categories.to_a.count
@@ -59,7 +55,7 @@ class CascadedEagerLoadingTest < ActiveRecord::TestCase
   end
 
   def test_cascaded_eager_association_loading_with_duplicated_includes
-    categories = Category.includes(:categorizations).includes(:categorizations => :author).where("categorizations.id is not null").references(:categorizations)
+    categories = Category.includes(:categorizations).includes(categorizations: :author).where("categorizations.id is not null").references(:categorizations)
     assert_nothing_raised do
       assert_equal 3, categories.count
       assert_equal 3, categories.to_a.size
@@ -67,7 +63,7 @@ class CascadedEagerLoadingTest < ActiveRecord::TestCase
   end
 
   def test_cascaded_eager_association_loading_with_twice_includes_edge_cases
-    categories = Category.includes(:categorizations => :author).includes(:categorizations => :post).where("posts.id is not null").references(:posts)
+    categories = Category.includes(categorizations: :author).includes(categorizations: :post).where("posts.id is not null").references(:posts)
     assert_nothing_raised do
       assert_equal 3, categories.count
       assert_equal 3, categories.to_a.size
@@ -82,29 +78,29 @@ class CascadedEagerLoadingTest < ActiveRecord::TestCase
   end
 
   def test_eager_association_loading_with_cascaded_two_levels_with_two_has_many_associations
-    authors = Author.all.merge!(:includes=>{:posts=>[:comments, :categorizations]}, :order=>"authors.id").to_a
+    authors = Author.all.merge!(includes: { posts: [:comments, :categorizations] }, order: "authors.id").to_a
     assert_equal 3, authors.size
     assert_equal 5, authors[0].posts.size
     assert_equal 3, authors[1].posts.size
-    assert_equal 10, authors[0].posts.collect{|post| post.comments.size }.inject(0){|sum,i| sum+i}
+    assert_equal 10, authors[0].posts.collect { |post| post.comments.size }.inject(0) { |sum, i| sum + i }
   end
 
   def test_eager_association_loading_with_cascaded_two_levels_and_self_table_reference
-    authors = Author.all.merge!(:includes=>{:posts=>[:comments, :author]}, :order=>"authors.id").to_a
+    authors = Author.all.merge!(includes: { posts: [:comments, :author] }, order: "authors.id").to_a
     assert_equal 3, authors.size
     assert_equal 5, authors[0].posts.size
     assert_equal authors(:david).name, authors[0].name
-    assert_equal [authors(:david).name], authors[0].posts.collect{|post| post.author.name}.uniq
+    assert_equal [authors(:david).name], authors[0].posts.collect { |post| post.author.name }.uniq
   end
 
   def test_eager_association_loading_with_cascaded_two_levels_with_condition
-    authors = Author.all.merge!(:includes=>{:posts=>:comments}, :where=>"authors.id=1", :order=>"authors.id").to_a
+    authors = Author.all.merge!(includes: { posts: :comments }, where: "authors.id=1", order: "authors.id").to_a
     assert_equal 1, authors.size
     assert_equal 5, authors[0].posts.size
   end
 
   def test_eager_association_loading_with_cascaded_three_levels_by_ping_pong
-    firms = Firm.all.merge!(:includes=>{:account=>{:firm=>:account}}, :order=>"companies.id").to_a
+    firms = Firm.all.merge!(includes: { account: { firm: :account } }, order: "companies.id").to_a
     assert_equal 2, firms.size
     assert_equal firms.first.account, firms.first.account.firm.account
     assert_equal companies(:first_firm).account, assert_no_queries { firms.first.account.firm.account }
@@ -112,7 +108,7 @@ class CascadedEagerLoadingTest < ActiveRecord::TestCase
   end
 
   def test_eager_association_loading_with_has_many_sti
-    topics = Topic.all.merge!(:includes => :replies, :order => 'topics.id').to_a
+    topics = Topic.all.merge!(includes: :replies, order: "topics.id").to_a
     first, second, = topics(:first).replies.size, topics(:second).replies.size
     assert_no_queries do
       assert_equal first, topics[0].replies.size
@@ -121,11 +117,11 @@ class CascadedEagerLoadingTest < ActiveRecord::TestCase
   end
 
   def test_eager_association_loading_with_has_many_sti_and_subclasses
-    silly = SillyReply.new(:title => "gaga", :content => "boo-boo", :parent_id => 1)
+    silly = SillyReply.new(title: "gaga", content: "boo-boo", parent_id: 1)
     silly.parent_id = 1
     assert silly.save
 
-    topics = Topic.all.merge!(:includes => :replies, :order => ['topics.id', 'replies_topics.id']).to_a
+    topics = Topic.all.merge!(includes: :replies, order: ["topics.id", "replies_topics.id"]).to_a
     assert_no_queries do
       assert_equal 2, topics[0].replies.size
       assert_equal 0, topics[1].replies.size
@@ -133,14 +129,14 @@ class CascadedEagerLoadingTest < ActiveRecord::TestCase
   end
 
   def test_eager_association_loading_with_belongs_to_sti
-    replies = Reply.all.merge!(:includes => :topic, :order => 'topics.id').to_a
-    assert replies.include?(topics(:second))
-    assert !replies.include?(topics(:first))
+    replies = Reply.all.merge!(includes: :topic, order: "topics.id").to_a
+    assert_includes replies, topics(:second)
+    assert_not_includes replies, topics(:first)
     assert_equal topics(:first), assert_no_queries { replies.first.topic }
   end
 
   def test_eager_association_loading_with_multiple_stis_and_order
-    author = Author.all.merge!(:includes => { :posts => [ :special_comments , :very_special_comment ] }, :order => ['authors.name', 'comments.body', 'very_special_comments_posts.body'], :where => 'posts.id = 4').first
+    author = Author.all.merge!(includes: { posts: [ :special_comments, :very_special_comment ] }, order: ["authors.name", "comments.body", "very_special_comments_posts.body"], where: "posts.id = 4").first
     assert_equal authors(:david), author
     assert_no_queries do
       author.posts.first.special_comments
@@ -149,7 +145,7 @@ class CascadedEagerLoadingTest < ActiveRecord::TestCase
   end
 
   def test_eager_association_loading_of_stis_with_multiple_references
-    authors = Author.all.merge!(:includes => { :posts => { :special_comments => { :post => [ :special_comments, :very_special_comment ] } } }, :order => 'comments.body, very_special_comments_posts.body', :where => 'posts.id = 4').to_a
+    authors = Author.all.merge!(includes: { posts: { special_comments: { post: [ :special_comments, :very_special_comment ] } } }, order: "comments.body, very_special_comments_posts.body", where: "posts.id = 4").to_a
     assert_equal [authors(:david)], authors
     assert_no_queries do
       authors.first.posts.first.special_comments.first.post.special_comments
@@ -158,7 +154,7 @@ class CascadedEagerLoadingTest < ActiveRecord::TestCase
   end
 
   def test_eager_association_loading_where_first_level_returns_nil
-    authors = Author.all.merge!(:includes => {:post_about_thinking => :comments}, :order => 'authors.id DESC').to_a
+    authors = Author.all.merge!(includes: { post_about_thinking: :comments }, order: "authors.id DESC").to_a
     assert_equal [authors(:bob), authors(:mary), authors(:david)], authors
     assert_no_queries do
       authors[2].post_about_thinking.comments.first
@@ -166,12 +162,12 @@ class CascadedEagerLoadingTest < ActiveRecord::TestCase
   end
 
   def test_eager_association_loading_with_recursive_cascading_four_levels_has_many_through
-    source = Vertex.all.merge!(:includes=>{:sinks=>{:sinks=>{:sinks=>:sinks}}}, :order => 'vertices.id').first
+    source = Vertex.all.merge!(includes: { sinks: { sinks: { sinks: :sinks } } }, order: "vertices.id").first
     assert_equal vertices(:vertex_4), assert_no_queries { source.sinks.first.sinks.first.sinks.first }
   end
 
   def test_eager_association_loading_with_recursive_cascading_four_levels_has_and_belongs_to_many
-    sink = Vertex.all.merge!(:includes=>{:sources=>{:sources=>{:sources=>:sources}}}, :order => 'vertices.id DESC').first
+    sink = Vertex.all.merge!(includes: { sources: { sources: { sources: :sources } } }, order: "vertices.id DESC").first
     assert_equal vertices(:vertex_1), assert_no_queries { sink.sources.first.sources.first.sources.first.sources.first }
   end
 
@@ -183,6 +179,6 @@ class CascadedEagerLoadingTest < ActiveRecord::TestCase
     assert_equal 1, authors[1].comments.size
     assert_equal 5, authors[0].posts.size
     assert_equal 3, authors[1].posts.size
-    assert_equal 3, authors[0].posts.collect { |post| post.categorizations.size }.inject(0) { |sum, i| sum+i }
+    assert_equal 3, authors[0].posts.collect { |post| post.categorizations.size }.inject(0) { |sum, i| sum + i }
   end
 end
diff --git a/activerecord/test/cases/associations/eager_load_includes_full_sti_class_test.rb b/activerecord/test/cases/associations/eager_load_includes_full_sti_class_test.rb
index 75a6295350..8754889143 100644
--- a/activerecord/test/cases/associations/eager_load_includes_full_sti_class_test.rb
+++ b/activerecord/test/cases/associations/eager_load_includes_full_sti_class_test.rb
@@ -1,36 +1,44 @@
-require 'cases/helper'
-require 'models/post'
-require 'models/tagging'
+# frozen_string_literal: true
+
+require "cases/helper"
+require "models/post"
+require "models/tagging"
 
 module Namespaced
   class Post < ActiveRecord::Base
-    self.table_name = 'posts'
-    has_one :tagging, :as => :taggable, :class_name => 'Tagging'
+    self.table_name = "posts"
+    has_one :tagging, as: :taggable, class_name: "Tagging"
   end
 end
 
 class EagerLoadIncludeFullStiClassNamesTest < ActiveRecord::TestCase
-
   def setup
-    generate_test_objects
+    post = Namespaced::Post.create(title: "Great stuff", body: "This is not", author_id: 1)
+    @tagging = Tagging.create(taggable: post)
+    @old = ActiveRecord::Base.store_full_sti_class
   end
 
-  def generate_test_objects
-    post = Namespaced::Post.create( :title => 'Great stuff', :body => 'This is not', :author_id => 1 )
-    Tagging.create( :taggable => post )
+  def teardown
+    ActiveRecord::Base.store_full_sti_class = @old
   end
 
-  def test_class_names
-    old = ActiveRecord::Base.store_full_sti_class
+  def test_class_names_with_includes
+    ActiveRecord::Base.store_full_sti_class = false
+    post = Namespaced::Post.includes(:tagging).find_by_title("Great stuff")
+    assert_nil post.tagging
+
+    ActiveRecord::Base.store_full_sti_class = true
+    post = Namespaced::Post.includes(:tagging).find_by_title("Great stuff")
+    assert_equal @tagging, post.tagging
+  end
 
+  def test_class_names_with_eager_load
     ActiveRecord::Base.store_full_sti_class = false
-    post = Namespaced::Post.includes(:tagging).find_by_title('Great stuff')
+    post = Namespaced::Post.eager_load(:tagging).find_by_title("Great stuff")
     assert_nil post.tagging
 
     ActiveRecord::Base.store_full_sti_class = true
-    post = Namespaced::Post.includes(:tagging).find_by_title('Great stuff')
-    assert_instance_of Tagging, post.tagging
-  ensure
-    ActiveRecord::Base.store_full_sti_class = old
+    post = Namespaced::Post.eager_load(:tagging).find_by_title("Great stuff")
+    assert_equal @tagging, post.tagging
   end
 end
diff --git a/activerecord/test/cases/associations/eager_load_nested_include_test.rb b/activerecord/test/cases/associations/eager_load_nested_include_test.rb
index f571198079..c5b2b77bd4 100644
--- a/activerecord/test/cases/associations/eager_load_nested_include_test.rb
+++ b/activerecord/test/cases/associations/eager_load_nested_include_test.rb
@@ -1,18 +1,20 @@
-require 'cases/helper'
-require 'models/post'
-require 'models/tag'
-require 'models/author'
-require 'models/comment'
-require 'models/category'
-require 'models/categorization'
-require 'models/tagging'
+# frozen_string_literal: true
+
+require "cases/helper"
+require "models/post"
+require "models/tag"
+require "models/author"
+require "models/comment"
+require "models/category"
+require "models/categorization"
+require "models/tagging"
 
 module Remembered
   extend ActiveSupport::Concern
 
   included do
     after_create :remember
-  protected
+  private
     def remember; self.class.remembered << self; end
   end
 
@@ -23,30 +25,30 @@ module Remembered
 end
 
 class ShapeExpression < ActiveRecord::Base
-  belongs_to :shape, :polymorphic => true
-  belongs_to :paint, :polymorphic => true
+  belongs_to :shape, polymorphic: true
+  belongs_to :paint, polymorphic: true
 end
 
 class Circle < ActiveRecord::Base
-  has_many :shape_expressions, :as => :shape
+  has_many :shape_expressions, as: :shape
   include Remembered
 end
 class Square < ActiveRecord::Base
-  has_many :shape_expressions, :as => :shape
+  has_many :shape_expressions, as: :shape
   include Remembered
 end
 class Triangle < ActiveRecord::Base
-  has_many :shape_expressions, :as => :shape
+  has_many :shape_expressions, as: :shape
   include Remembered
 end
-class PaintColor  < ActiveRecord::Base
-  has_many   :shape_expressions, :as => :paint
-  belongs_to :non_poly, :foreign_key => "non_poly_one_id", :class_name => "NonPolyOne"
+class PaintColor < ActiveRecord::Base
+  has_many   :shape_expressions, as: :paint
+  belongs_to :non_poly, foreign_key: "non_poly_one_id", class_name: "NonPolyOne"
   include Remembered
 end
 class PaintTexture < ActiveRecord::Base
-  has_many   :shape_expressions, :as => :paint
-  belongs_to :non_poly, :foreign_key => "non_poly_two_id", :class_name => "NonPolyTwo"
+  has_many   :shape_expressions, as: :paint
+  belongs_to :non_poly, foreign_key: "non_poly_two_id", class_name: "NonPolyTwo"
   include Remembered
 end
 class NonPolyOne < ActiveRecord::Base
@@ -58,8 +60,6 @@ class NonPolyTwo < ActiveRecord::Base
   include Remembered
 end
 
-
-
 class EagerLoadPolyAssocsTest < ActiveRecord::TestCase
   NUM_SIMPLE_OBJS = 50
   NUM_SHAPE_EXPRESSIONS = 100
@@ -78,19 +78,19 @@ class EagerLoadPolyAssocsTest < ActiveRecord::TestCase
       [Circle, Square, Triangle, NonPolyOne, NonPolyTwo].map(&:create!)
     end
     1.upto(NUM_SIMPLE_OBJS) do
-      PaintColor.create!(:non_poly_one_id => NonPolyOne.sample.id)
-      PaintTexture.create!(:non_poly_two_id => NonPolyTwo.sample.id)
+      PaintColor.create!(non_poly_one_id: NonPolyOne.sample.id)
+      PaintTexture.create!(non_poly_two_id: NonPolyTwo.sample.id)
     end
     1.upto(NUM_SHAPE_EXPRESSIONS) do
       shape_type = [Circle, Square, Triangle].sample
       paint_type = [PaintColor, PaintTexture].sample
-      ShapeExpression.create!(:shape_type => shape_type.to_s, :shape_id => shape_type.sample.id,
-                              :paint_type => paint_type.to_s, :paint_id => paint_type.sample.id)
+      ShapeExpression.create!(shape_type: shape_type.to_s, shape_id: shape_type.sample.id,
+                              paint_type: paint_type.to_s, paint_id: paint_type.sample.id)
     end
   end
 
   def test_include_query
-    res = ShapeExpression.all.merge!(:includes => [ :shape, { :paint => :non_poly } ]).to_a
+    res = ShapeExpression.all.merge!(includes: [ :shape, { paint: :non_poly } ]).to_a
     assert_equal NUM_SHAPE_EXPRESSIONS, res.size
     assert_queries(0) do
       res.each do |se|
@@ -103,10 +103,10 @@ end
 
 class EagerLoadNestedIncludeWithMissingDataTest < ActiveRecord::TestCase
   def setup
-    @davey_mcdave = Author.create(:name => 'Davey McDave')
-    @first_post = @davey_mcdave.posts.create(:title => 'Davey Speaks', :body => 'Expressive wordage')
-    @first_comment = @first_post.comments.create(:body => 'Inflamatory doublespeak')
-    @first_categorization = @davey_mcdave.categorizations.create(:category => Category.first, :post => @first_post)
+    @davey_mcdave = Author.create(name: "Davey McDave")
+    @first_post = @davey_mcdave.posts.create(title: "Davey Speaks", body: "Expressive wordage")
+    @first_comment = @first_post.comments.create(body: "Inflamatory doublespeak")
+    @first_categorization = @davey_mcdave.categorizations.create(category: Category.first, post: @first_post)
   end
 
   teardown do
@@ -119,8 +119,8 @@ class EagerLoadNestedIncludeWithMissingDataTest < ActiveRecord::TestCase
   def test_missing_data_in_a_nested_include_should_not_cause_errors_when_constructing_objects
     assert_nothing_raised do
       # @davey_mcdave doesn't have any author_favorites
-      includes = {:posts => :comments, :categorizations => :category, :author_favorites => :favorite_author }
-      Author.all.merge!(:includes => includes, :where => {:authors => {:name => @davey_mcdave.name}}, :order => 'categories.name').to_a
+      includes = { posts: :comments, categorizations: :category, author_favorites: :favorite_author }
+      Author.all.merge!(includes: includes, where: { authors: { name: @davey_mcdave.name } }, order: "categories.name").to_a
     end
   end
 end
diff --git a/activerecord/test/cases/associations/eager_singularization_test.rb b/activerecord/test/cases/associations/eager_singularization_test.rb
index a61a070331..420a5a805b 100644
--- a/activerecord/test/cases/associations/eager_singularization_test.rb
+++ b/activerecord/test/cases/associations/eager_singularization_test.rb
@@ -1,7 +1,7 @@
-require "cases/helper"
+# frozen_string_literal: true
 
+require "cases/helper"
 
-if ActiveRecord::Base.connection.supports_migrations?
 class EagerSingularizationTest < ActiveRecord::TestCase
   class Virus < ActiveRecord::Base
     belongs_to :octopus
@@ -25,10 +25,10 @@ class EagerSingularizationTest < ActiveRecord::TestCase
 
   class Crisis < ActiveRecord::Base
     has_and_belongs_to_many :messes
-    has_many :analyses, :dependent => :destroy
-    has_many :successes, :through => :analyses
-    has_many :dresses, :dependent => :destroy
-    has_many :compresses, :through => :dresses
+    has_many :analyses, dependent: :destroy
+    has_many :successes, through: :analyses
+    has_many :dresses, dependent: :destroy
+    has_many :compresses, through: :dresses
   end
 
   class Analysis < ActiveRecord::Base
@@ -37,8 +37,8 @@ class EagerSingularizationTest < ActiveRecord::TestCase
   end
 
   class Success < ActiveRecord::Base
-    has_many :analyses, :dependent => :destroy
-    has_many :crises, :through => :analyses
+    has_many :analyses, dependent: :destroy
+    has_many :crises, through: :analyses
   end
 
   class Dress < ActiveRecord::Base
@@ -65,7 +65,7 @@ class EagerSingularizationTest < ActiveRecord::TestCase
     connection.create_table :buses do |t|
       t.column :name, :string
     end
-    connection.create_table :crises_messes, :id => false do |t|
+    connection.create_table :crises_messes, id: false do |t|
       t.column :crisis_id, :integer
       t.column :mess_id, :integer
     end
@@ -104,45 +104,45 @@ class EagerSingularizationTest < ActiveRecord::TestCase
     connection.drop_table :compresses
   end
 
-  def connection
-    ActiveRecord::Base.connection
-  end
-
   def test_eager_no_extra_singularization_belongs_to
     assert_nothing_raised do
-      Virus.all.merge!(:includes => :octopus).to_a
+      Virus.all.merge!(includes: :octopus).to_a
     end
   end
 
   def test_eager_no_extra_singularization_has_one
     assert_nothing_raised do
-      Octopus.all.merge!(:includes => :virus).to_a
+      Octopus.all.merge!(includes: :virus).to_a
     end
   end
 
   def test_eager_no_extra_singularization_has_many
     assert_nothing_raised do
-      Bus.all.merge!(:includes => :passes).to_a
+      Bus.all.merge!(includes: :passes).to_a
     end
   end
 
   def test_eager_no_extra_singularization_has_and_belongs_to_many
     assert_nothing_raised do
-      Crisis.all.merge!(:includes => :messes).to_a
-      Mess.all.merge!(:includes => :crises).to_a
+      Crisis.all.merge!(includes: :messes).to_a
+      Mess.all.merge!(includes: :crises).to_a
     end
   end
 
   def test_eager_no_extra_singularization_has_many_through_belongs_to
     assert_nothing_raised do
-      Crisis.all.merge!(:includes => :successes).to_a
+      Crisis.all.merge!(includes: :successes).to_a
     end
   end
 
   def test_eager_no_extra_singularization_has_many_through_has_many
     assert_nothing_raised do
-      Crisis.all.merge!(:includes => :compresses).to_a
+      Crisis.all.merge!(includes: :compresses).to_a
     end
   end
-end
+
+  private
+    def connection
+      ActiveRecord::Base.connection
+    end
 end
diff --git a/activerecord/test/cases/associations/eager_test.rb b/activerecord/test/cases/associations/eager_test.rb
index 80d9a6083b..2649dc010f 100644
--- a/activerecord/test/cases/associations/eager_test.rb
+++ b/activerecord/test/cases/associations/eager_test.rb
@@ -1,31 +1,33 @@
+# frozen_string_literal: true
+
 require "cases/helper"
-require 'models/post'
-require 'models/tagging'
-require 'models/tag'
-require 'models/comment'
-require 'models/author'
-require 'models/essay'
-require 'models/category'
-require 'models/company'
-require 'models/person'
-require 'models/reader'
-require 'models/owner'
-require 'models/pet'
-require 'models/reference'
-require 'models/job'
-require 'models/subscriber'
-require 'models/subscription'
-require 'models/book'
-require 'models/developer'
-require 'models/computer'
-require 'models/project'
-require 'models/member'
-require 'models/membership'
-require 'models/club'
-require 'models/categorization'
-require 'models/sponsor'
-require 'models/mentor'
-require 'models/contract'
+require "models/post"
+require "models/tagging"
+require "models/tag"
+require "models/comment"
+require "models/author"
+require "models/essay"
+require "models/category"
+require "models/company"
+require "models/person"
+require "models/reader"
+require "models/owner"
+require "models/pet"
+require "models/reference"
+require "models/job"
+require "models/subscriber"
+require "models/subscription"
+require "models/book"
+require "models/developer"
+require "models/computer"
+require "models/project"
+require "models/member"
+require "models/membership"
+require "models/club"
+require "models/categorization"
+require "models/sponsor"
+require "models/mentor"
+require "models/contract"
 
 class EagerAssociationTest < ActiveRecord::TestCase
   fixtures :posts, :comments, :authors, :essays, :author_addresses, :categories, :categories_posts,
@@ -34,42 +36,53 @@ class EagerAssociationTest < ActiveRecord::TestCase
             :developers, :projects, :developers_projects, :members, :memberships, :clubs, :sponsors
 
   def test_eager_with_has_one_through_join_model_with_conditions_on_the_through
-    member = Member.all.merge!(:includes => :favourite_club).find(members(:some_other_guy).id)
+    member = Member.all.merge!(includes: :favourite_club).find(members(:some_other_guy).id)
     assert_nil member.favourite_club
   end
 
+  def test_should_work_inverse_of_with_eager_load
+    author = authors(:david)
+    assert_same author, author.posts.first.author
+    assert_same author, author.posts.eager_load(:comments).first.author
+  end
+
   def test_loading_with_one_association
-    posts = Post.all.merge!(:includes => :comments).to_a
+    posts = Post.all.merge!(includes: :comments).to_a
     post = posts.find { |p| p.id == 1 }
     assert_equal 2, post.comments.size
-    assert post.comments.include?(comments(:greetings))
+    assert_includes post.comments, comments(:greetings)
 
-    post = Post.all.merge!(:includes => :comments, :where => "posts.title = 'Welcome to the weblog'").first
+    post = Post.all.merge!(includes: :comments, where: "posts.title = 'Welcome to the weblog'").first
     assert_equal 2, post.comments.size
-    assert post.comments.include?(comments(:greetings))
+    assert_includes post.comments, comments(:greetings)
 
-    posts = Post.all.merge!(:includes => :last_comment).to_a
+    posts = Post.all.merge!(includes: :last_comment).to_a
     post = posts.find { |p| p.id == 1 }
     assert_equal Post.find(1).last_comment, post.last_comment
   end
 
   def test_loading_with_one_association_with_non_preload
-    posts = Post.all.merge!(:includes => :last_comment, :order => 'comments.id DESC').to_a
+    posts = Post.all.merge!(includes: :last_comment, order: "comments.id DESC").to_a
     post = posts.find { |p| p.id == 1 }
     assert_equal Post.find(1).last_comment, post.last_comment
   end
 
   def test_loading_conditions_with_or
     posts = authors(:david).posts.references(:comments).merge(
-      :includes => :comments,
-      :where => "comments.body like 'Normal%' OR comments.#{QUOTED_TYPE} = 'SpecialComment'"
+      includes: :comments,
+      where: "comments.body like 'Normal%' OR comments.#{QUOTED_TYPE} = 'SpecialComment'"
     ).to_a
     assert_nil posts.detect { |p| p.author_id != authors(:david).id },
       "expected to find only david's posts"
   end
 
+  def test_loading_with_scope_including_joins
+    assert_equal clubs(:boring_club), Member.preload(:general_club).find(1).general_club
+    assert_equal clubs(:boring_club), Member.eager_load(:general_club).find(1).general_club
+  end
+
   def test_with_ordering
-    list = Post.all.merge!(:includes => :comments, :order => "posts.id DESC").to_a
+    list = Post.all.merge!(includes: :comments, order: "posts.id DESC").to_a
     [:other_by_mary, :other_by_bob, :misc_by_mary, :misc_by_bob, :eager_other,
      :sti_habtm, :sti_post_and_comments, :sti_comments, :authorless, :thinking, :welcome
     ].each_with_index do |post, index|
@@ -100,43 +113,43 @@ class EagerAssociationTest < ActiveRecord::TestCase
   end
 
   def test_loading_with_multiple_associations
-    posts = Post.all.merge!(:includes => [ :comments, :author, :categories ], :order => "posts.id").to_a
+    posts = Post.all.merge!(includes: [ :comments, :author, :categories ], order: "posts.id").to_a
     assert_equal 2, posts.first.comments.size
     assert_equal 2, posts.first.categories.size
-    assert posts.first.comments.include?(comments(:greetings))
+    assert_includes posts.first.comments, comments(:greetings)
   end
 
   def test_duplicate_middle_objects
-    comments = Comment.all.merge!(:where => 'post_id = 1', :includes => [:post => :author]).to_a
+    comments = Comment.all.merge!(where: "post_id = 1", includes: [post: :author]).to_a
     assert_no_queries do
-      comments.each {|comment| comment.post.author.name}
+      comments.each { |comment| comment.post.author.name }
     end
   end
 
   def test_preloading_has_many_in_multiple_queries_with_more_ids_than_database_can_handle
     assert_called(Comment.connection, :in_clause_length, returns: 5) do
-      posts = Post.all.merge!(:includes=>:comments).to_a
+      posts = Post.all.merge!(includes: :comments).to_a
       assert_equal 11, posts.size
     end
   end
 
   def test_preloading_has_many_in_one_queries_when_database_has_no_limit_on_ids_it_can_handle
     assert_called(Comment.connection, :in_clause_length, returns: nil) do
-      posts = Post.all.merge!(:includes=>:comments).to_a
+      posts = Post.all.merge!(includes: :comments).to_a
       assert_equal 11, posts.size
     end
   end
 
   def test_preloading_habtm_in_multiple_queries_with_more_ids_than_database_can_handle
     assert_called(Comment.connection, :in_clause_length, times: 2, returns: 5) do
-      posts = Post.all.merge!(:includes=>:categories).to_a
+      posts = Post.all.merge!(includes: :categories).to_a
       assert_equal 11, posts.size
     end
   end
 
   def test_preloading_habtm_in_one_queries_when_database_has_no_limit_on_ids_it_can_handle
     assert_called(Comment.connection, :in_clause_length, times: 2, returns: nil) do
-      posts = Post.all.merge!(:includes=>:categories).to_a
+      posts = Post.all.merge!(includes: :categories).to_a
       assert_equal 11, posts.size
     end
   end
@@ -145,7 +158,7 @@ class EagerAssociationTest < ActiveRecord::TestCase
     assert_called(Comment.connection, :in_clause_length, returns: nil) do
       post = posts(:welcome)
       assert_queries(2) do
-        Post.includes(:comments).where(:id => post.id).to_a
+        Post.includes(:comments).where(id: post.id).to_a
       end
     end
   end
@@ -154,7 +167,7 @@ class EagerAssociationTest < ActiveRecord::TestCase
     assert_called(Comment.connection, :in_clause_length, returns: 1) do
       post1, post2 = posts(:welcome), posts(:thinking)
       assert_queries(3) do
-        Post.includes(:comments).where(:id => [post1.id, post2.id]).to_a
+        Post.includes(:comments).where(id: [post1.id, post2.id]).to_a
       end
     end
   end
@@ -163,50 +176,50 @@ class EagerAssociationTest < ActiveRecord::TestCase
     assert_called(Comment.connection, :in_clause_length, returns: 3) do
       post = posts(:welcome)
       assert_queries(2) do
-        Post.includes(:comments).where(:id => post.id).to_a
+        Post.includes(:comments).where(id: post.id).to_a
       end
     end
   end
 
   def test_including_duplicate_objects_from_belongs_to
-    popular_post = Post.create!(:title => 'foo', :body => "I like cars!")
-    comment = popular_post.comments.create!(:body => "lol")
-    popular_post.readers.create!(:person => people(:michael))
-    popular_post.readers.create!(:person => people(:david))
+    popular_post = Post.create!(title: "foo", body: "I like cars!")
+    comment = popular_post.comments.create!(body: "lol")
+    popular_post.readers.create!(person: people(:michael))
+    popular_post.readers.create!(person: people(:david))
 
-    readers = Reader.all.merge!(:where => ["post_id = ?", popular_post.id],
-                                :includes => {:post => :comments}).to_a
+    readers = Reader.all.merge!(where: ["post_id = ?", popular_post.id],
+                                includes: { post: :comments }).to_a
     readers.each do |reader|
       assert_equal [comment], reader.post.comments
     end
   end
 
   def test_including_duplicate_objects_from_has_many
-    car_post = Post.create!(:title => 'foo', :body => "I like cars!")
+    car_post = Post.create!(title: "foo", body: "I like cars!")
     car_post.categories << categories(:general)
     car_post.categories << categories(:technology)
 
-    comment = car_post.comments.create!(:body => "hmm")
-    categories = Category.all.merge!(:where => { 'posts.id' => car_post.id },
-                                 :includes => {:posts => :comments}).to_a
+    comment = car_post.comments.create!(body: "hmm")
+    categories = Category.all.merge!(where: { "posts.id" => car_post.id },
+                                 includes: { posts: :comments }).to_a
     categories.each do |category|
       assert_equal [comment], category.posts[0].comments
     end
   end
 
   def test_associations_loaded_for_all_records
-    post = Post.create!(:title => 'foo', :body => "I like cars!")
-    SpecialComment.create!(:body => 'Come on!', :post => post)
-    first_category = Category.create! :name => 'First!', :posts => [post]
-    second_category = Category.create! :name => 'Second!', :posts => [post]
+    post = Post.create!(title: "foo", body: "I like cars!")
+    SpecialComment.create!(body: "Come on!", post: post)
+    first_category = Category.create! name: "First!", posts: [post]
+    second_category = Category.create! name: "Second!", posts: [post]
 
-    categories = Category.where(:id => [first_category.id, second_category.id]).includes(:posts => :special_comments)
+    categories = Category.where(id: [first_category.id, second_category.id]).includes(posts: :special_comments)
     assert_equal categories.map { |category| category.posts.first.special_comments.loaded? }, [true, true]
   end
 
   def test_finding_with_includes_on_has_many_association_with_same_include_includes_only_once
     author_id = authors(:david).id
-    author = assert_queries(3) { Author.all.merge!(:includes => {:posts_with_comments => :comments}).find(author_id) } # find the author, then find the posts, then find the comments
+    author = assert_queries(3) { Author.all.merge!(includes: { posts_with_comments: :comments }).find(author_id) } # find the author, then find the posts, then find the comments
     author.posts_with_comments.each do |post_with_comments|
       assert_equal post_with_comments.comments.length, post_with_comments.comments.count
       assert_nil post_with_comments.comments.to_a.uniq!
@@ -217,7 +230,7 @@ class EagerAssociationTest < ActiveRecord::TestCase
     author = authors(:david)
     post = author.post_about_thinking_with_last_comment
     last_comment = post.last_comment
-    author = assert_queries(3) { Author.all.merge!(:includes => {:post_about_thinking_with_last_comment => :last_comment}).find(author.id)} # find the author, then find the posts, then find the comments
+    author = assert_queries(3) { Author.all.merge!(includes: { post_about_thinking_with_last_comment: :last_comment }).find(author.id) } # find the author, then find the posts, then find the comments
     assert_no_queries do
       assert_equal post, author.post_about_thinking_with_last_comment
       assert_equal last_comment, author.post_about_thinking_with_last_comment.last_comment
@@ -228,7 +241,7 @@ class EagerAssociationTest < ActiveRecord::TestCase
     post = posts(:welcome)
     author = post.author
     author_address = author.author_address
-    post = assert_queries(3) { Post.all.merge!(:includes => {:author_with_address => :author_address}).find(post.id) } # find the post, then find the author, then find the address
+    post = assert_queries(3) { Post.all.merge!(includes: { author_with_address: :author_address }).find(post.id) } # find the post, then find the author, then find the address
     assert_no_queries do
       assert_equal author, post.author_with_address
       assert_equal author_address, post.author_with_address.author_address
@@ -238,53 +251,50 @@ class EagerAssociationTest < ActiveRecord::TestCase
   def test_finding_with_includes_on_null_belongs_to_association_with_same_include_includes_only_once
     post = posts(:welcome)
     post.update!(author: nil)
-    post = assert_queries(1) { Post.all.merge!(includes: {author_with_address: :author_address}).find(post.id) }
+    post = assert_queries(1) { Post.all.merge!(includes: { author_with_address: :author_address }).find(post.id) }
     # find the post, then find the author which is null so no query for the author or address
     assert_no_queries do
-      assert_equal nil, post.author_with_address
+      assert_nil post.author_with_address
     end
   end
 
   def test_finding_with_includes_on_null_belongs_to_polymorphic_association
     sponsor = sponsors(:moustache_club_sponsor_for_groucho)
     sponsor.update!(sponsorable: nil)
-    sponsor = assert_queries(1) { Sponsor.all.merge!(:includes => :sponsorable).find(sponsor.id) }
+    sponsor = assert_queries(1) { Sponsor.all.merge!(includes: :sponsorable).find(sponsor.id) }
     assert_no_queries do
-      assert_equal nil, sponsor.sponsorable
+      assert_nil sponsor.sponsorable
     end
   end
 
   def test_finding_with_includes_on_empty_polymorphic_type_column
     sponsor = sponsors(:moustache_club_sponsor_for_groucho)
-    sponsor.update!(sponsorable_type: '', sponsorable_id: nil) # sponsorable_type column might be declared NOT NULL
+    sponsor.update!(sponsorable_type: "", sponsorable_id: nil) # sponsorable_type column might be declared NOT NULL
     sponsor = assert_queries(1) do
-      assert_nothing_raised { Sponsor.all.merge!(:includes => :sponsorable).find(sponsor.id) }
+      assert_nothing_raised { Sponsor.all.merge!(includes: :sponsorable).find(sponsor.id) }
     end
     assert_no_queries do
-      assert_equal nil, sponsor.sponsorable
+      assert_nil sponsor.sponsorable
     end
   end
 
   def test_loading_from_an_association
-    posts = authors(:david).posts.merge(:includes => :comments, :order => "posts.id").to_a
+    posts = authors(:david).posts.merge(includes: :comments, order: "posts.id").to_a
     assert_equal 2, posts.first.comments.size
   end
 
   def test_loading_from_an_association_that_has_a_hash_of_conditions
-    assert_nothing_raised do
-      Author.all.merge!(:includes => :hello_posts_with_hash_conditions).to_a
-    end
-    assert !Author.all.merge!(:includes => :hello_posts_with_hash_conditions).find(authors(:david).id).hello_posts.empty?
+    assert !Author.all.merge!(includes: :hello_posts_with_hash_conditions).find(authors(:david).id).hello_posts.empty?
   end
 
   def test_loading_with_no_associations
-    assert_nil Post.all.merge!(:includes => :author).find(posts(:authorless).id).author
+    assert_nil Post.all.merge!(includes: :author).find(posts(:authorless).id).author
   end
 
   # Regression test for 21c75e5
   def test_nested_loading_does_not_raise_exception_when_association_does_not_exist
     assert_nothing_raised do
-      Post.all.merge!(:includes => {:author => :author_addresss}).find(posts(:authorless).id)
+      Post.all.merge!(includes: { author: :author_addresss }).find(posts(:authorless).id)
     end
   end
 
@@ -292,117 +302,117 @@ class EagerAssociationTest < ActiveRecord::TestCase
     post_id = Comment.where(author_id: nil).where.not(post_id: nil).first.post_id
 
     assert_nothing_raised do
-      Post.preload(:comments => [{:author => :essays}]).find(post_id)
+      Post.preload(comments: [{ author: :essays }]).find(post_id)
     end
   end
 
   def test_nested_loading_through_has_one_association
-    aa = AuthorAddress.all.merge!(:includes => {:author => :posts}).find(author_addresses(:david_address).id)
+    aa = AuthorAddress.all.merge!(includes: { author: :posts }).find(author_addresses(:david_address).id)
     assert_equal aa.author.posts.count, aa.author.posts.length
   end
 
   def test_nested_loading_through_has_one_association_with_order
-    aa = AuthorAddress.all.merge!(:includes => {:author => :posts}, :order => 'author_addresses.id').find(author_addresses(:david_address).id)
+    aa = AuthorAddress.all.merge!(includes: { author: :posts }, order: "author_addresses.id").find(author_addresses(:david_address).id)
     assert_equal aa.author.posts.count, aa.author.posts.length
   end
 
   def test_nested_loading_through_has_one_association_with_order_on_association
-    aa = AuthorAddress.all.merge!(:includes => {:author => :posts}, :order => 'authors.id').find(author_addresses(:david_address).id)
+    aa = AuthorAddress.all.merge!(includes: { author: :posts }, order: "authors.id").find(author_addresses(:david_address).id)
     assert_equal aa.author.posts.count, aa.author.posts.length
   end
 
   def test_nested_loading_through_has_one_association_with_order_on_nested_association
-    aa = AuthorAddress.all.merge!(:includes => {:author => :posts}, :order => 'posts.id').find(author_addresses(:david_address).id)
+    aa = AuthorAddress.all.merge!(includes: { author: :posts }, order: "posts.id").find(author_addresses(:david_address).id)
     assert_equal aa.author.posts.count, aa.author.posts.length
   end
 
   def test_nested_loading_through_has_one_association_with_conditions
     aa = AuthorAddress.references(:author_addresses).merge(
-      :includes => {:author => :posts},
-      :where => "author_addresses.id > 0"
+      includes: { author: :posts },
+      where: "author_addresses.id > 0"
     ).find author_addresses(:david_address).id
     assert_equal aa.author.posts.count, aa.author.posts.length
   end
 
   def test_nested_loading_through_has_one_association_with_conditions_on_association
     aa = AuthorAddress.references(:authors).merge(
-      :includes => {:author => :posts},
-      :where => "authors.id > 0"
+      includes: { author: :posts },
+      where: "authors.id > 0"
     ).find author_addresses(:david_address).id
     assert_equal aa.author.posts.count, aa.author.posts.length
   end
 
   def test_nested_loading_through_has_one_association_with_conditions_on_nested_association
     aa = AuthorAddress.references(:posts).merge(
-      :includes => {:author => :posts},
-      :where => "posts.id > 0"
+      includes: { author: :posts },
+      where: "posts.id > 0"
     ).find author_addresses(:david_address).id
     assert_equal aa.author.posts.count, aa.author.posts.length
   end
 
   def test_eager_association_loading_with_belongs_to_and_foreign_keys
-    pets = Pet.all.merge!(:includes => :owner).to_a
+    pets = Pet.all.merge!(includes: :owner).to_a
     assert_equal 4, pets.length
   end
 
   def test_eager_association_loading_with_belongs_to
-    comments = Comment.all.merge!(:includes => :post).to_a
+    comments = Comment.all.merge!(includes: :post).to_a
     assert_equal 11, comments.length
     titles = comments.map { |c| c.post.title }
-    assert titles.include?(posts(:welcome).title)
-    assert titles.include?(posts(:sti_post_and_comments).title)
+    assert_includes titles, posts(:welcome).title
+    assert_includes titles, posts(:sti_post_and_comments).title
   end
 
   def test_eager_association_loading_with_belongs_to_and_limit
-    comments = Comment.all.merge!(:includes => :post, :limit => 5, :order => 'comments.id').to_a
+    comments = Comment.all.merge!(includes: :post, limit: 5, order: "comments.id").to_a
     assert_equal 5, comments.length
-    assert_equal [1,2,3,5,6], comments.collect(&:id)
+    assert_equal [1, 2, 3, 5, 6], comments.collect(&:id)
   end
 
   def test_eager_association_loading_with_belongs_to_and_limit_and_conditions
-    comments = Comment.all.merge!(:includes => :post, :where => 'post_id = 4', :limit => 3, :order => 'comments.id').to_a
+    comments = Comment.all.merge!(includes: :post, where: "post_id = 4", limit: 3, order: "comments.id").to_a
     assert_equal 3, comments.length
-    assert_equal [5,6,7], comments.collect(&:id)
+    assert_equal [5, 6, 7], comments.collect(&:id)
   end
 
   def test_eager_association_loading_with_belongs_to_and_limit_and_offset
-    comments = Comment.all.merge!(:includes => :post, :limit => 3, :offset => 2, :order => 'comments.id').to_a
+    comments = Comment.all.merge!(includes: :post, limit: 3, offset: 2, order: "comments.id").to_a
     assert_equal 3, comments.length
-    assert_equal [3,5,6], comments.collect(&:id)
+    assert_equal [3, 5, 6], comments.collect(&:id)
   end
 
   def test_eager_association_loading_with_belongs_to_and_limit_and_offset_and_conditions
-    comments = Comment.all.merge!(:includes => :post, :where => 'post_id = 4', :limit => 3, :offset => 1, :order => 'comments.id').to_a
+    comments = Comment.all.merge!(includes: :post, where: "post_id = 4", limit: 3, offset: 1, order: "comments.id").to_a
     assert_equal 3, comments.length
-    assert_equal [6,7,8], comments.collect(&:id)
+    assert_equal [6, 7, 8], comments.collect(&:id)
   end
 
   def test_eager_association_loading_with_belongs_to_and_limit_and_offset_and_conditions_array
-    comments = Comment.all.merge!(:includes => :post, :where => ['post_id = ?',4], :limit => 3, :offset => 1, :order => 'comments.id').to_a
+    comments = Comment.all.merge!(includes: :post, where: ["post_id = ?", 4], limit: 3, offset: 1, order: "comments.id").to_a
     assert_equal 3, comments.length
-    assert_equal [6,7,8], comments.collect(&:id)
+    assert_equal [6, 7, 8], comments.collect(&:id)
   end
 
   def test_eager_association_loading_with_belongs_to_and_conditions_string_with_unquoted_table_name
     assert_nothing_raised do
-      Comment.includes(:post).references(:posts).where('posts.id = ?', 4)
+      Comment.includes(:post).references(:posts).where("posts.id = ?", 4)
     end
   end
 
   def test_eager_association_loading_with_belongs_to_and_conditions_hash
     comments = []
     assert_nothing_raised do
-      comments = Comment.all.merge!(:includes => :post, :where => {:posts => {:id => 4}}, :limit => 3, :order => 'comments.id').to_a
+      comments = Comment.all.merge!(includes: :post, where: { posts: { id: 4 } }, limit: 3, order: "comments.id").to_a
     end
     assert_equal 3, comments.length
-    assert_equal [5,6,7], comments.collect(&:id)
+    assert_equal [5, 6, 7], comments.collect(&:id)
     assert_no_queries do
       comments.first.post
     end
   end
 
   def test_eager_association_loading_with_belongs_to_and_conditions_string_with_quoted_table_name
-    quoted_posts_id= Comment.connection.quote_table_name('posts') + '.' + Comment.connection.quote_column_name('id')
+    quoted_posts_id = Comment.connection.quote_table_name("posts") + "." + Comment.connection.quote_column_name("id")
     assert_nothing_raised do
       Comment.includes(:post).references(:posts).where("#{quoted_posts_id} = ?", 4)
     end
@@ -410,61 +420,61 @@ class EagerAssociationTest < ActiveRecord::TestCase
 
   def test_eager_association_loading_with_belongs_to_and_order_string_with_unquoted_table_name
     assert_nothing_raised do
-      Comment.all.merge!(:includes => :post, :order => 'posts.id').to_a
+      Comment.all.merge!(includes: :post, order: "posts.id").to_a
     end
   end
 
   def test_eager_association_loading_with_belongs_to_and_order_string_with_quoted_table_name
-    quoted_posts_id= Comment.connection.quote_table_name('posts') + '.' + Comment.connection.quote_column_name('id')
+    quoted_posts_id = Comment.connection.quote_table_name("posts") + "." + Comment.connection.quote_column_name("id")
     assert_nothing_raised do
-      Comment.includes(:post).references(:posts).order(quoted_posts_id)
+      Comment.includes(:post).references(:posts).order(Arel.sql(quoted_posts_id))
     end
   end
 
   def test_eager_association_loading_with_belongs_to_and_limit_and_multiple_associations
-    posts = Post.all.merge!(:includes => [:author, :very_special_comment], :limit => 1, :order => 'posts.id').to_a
+    posts = Post.all.merge!(includes: [:author, :very_special_comment], limit: 1, order: "posts.id").to_a
     assert_equal 1, posts.length
     assert_equal [1], posts.collect(&:id)
   end
 
   def test_eager_association_loading_with_belongs_to_and_limit_and_offset_and_multiple_associations
-    posts = Post.all.merge!(:includes => [:author, :very_special_comment], :limit => 1, :offset => 1, :order => 'posts.id').to_a
+    posts = Post.all.merge!(includes: [:author, :very_special_comment], limit: 1, offset: 1, order: "posts.id").to_a
     assert_equal 1, posts.length
     assert_equal [2], posts.collect(&:id)
   end
 
   def test_eager_association_loading_with_belongs_to_inferred_foreign_key_from_association_name
-    author_favorite = AuthorFavorite.all.merge!(:includes => :favorite_author).first
+    author_favorite = AuthorFavorite.all.merge!(includes: :favorite_author).first
     assert_equal authors(:mary), assert_no_queries { author_favorite.favorite_author }
   end
 
   def test_eager_load_belongs_to_quotes_table_and_column_names
     job = Job.includes(:ideal_reference).find jobs(:unicyclist).id
     references(:michael_unicyclist)
-    assert_no_queries{ assert_equal references(:michael_unicyclist), job.ideal_reference}
+    assert_no_queries { assert_equal references(:michael_unicyclist), job.ideal_reference }
   end
 
   def test_eager_load_has_one_quotes_table_and_column_names
-    michael = Person.all.merge!(:includes => :favourite_reference).find(people(:michael).id)
+    michael = Person.all.merge!(includes: :favourite_reference).find(people(:michael).id)
     references(:michael_unicyclist)
-    assert_no_queries{ assert_equal references(:michael_unicyclist), michael.favourite_reference}
+    assert_no_queries { assert_equal references(:michael_unicyclist), michael.favourite_reference }
   end
 
   def test_eager_load_has_many_quotes_table_and_column_names
-    michael = Person.all.merge!(:includes => :references).find(people(:michael).id)
-    references(:michael_magician,:michael_unicyclist)
-    assert_no_queries{ assert_equal references(:michael_magician,:michael_unicyclist), michael.references.sort_by(&:id) }
+    michael = Person.all.merge!(includes: :references).find(people(:michael).id)
+    references(:michael_magician, :michael_unicyclist)
+    assert_no_queries { assert_equal references(:michael_magician, :michael_unicyclist), michael.references.sort_by(&:id) }
   end
 
   def test_eager_load_has_many_through_quotes_table_and_column_names
-    michael = Person.all.merge!(:includes => :jobs).find(people(:michael).id)
+    michael = Person.all.merge!(includes: :jobs).find(people(:michael).id)
     jobs(:magician, :unicyclist)
-    assert_no_queries{ assert_equal jobs(:unicyclist, :magician), michael.jobs.sort_by(&:id) }
+    assert_no_queries { assert_equal jobs(:unicyclist, :magician), michael.jobs.sort_by(&:id) }
   end
 
   def test_eager_load_has_many_with_string_keys
     subscriptions = subscriptions(:webster_awdr, :webster_rfr)
-    subscriber =Subscriber.all.merge!(:includes => :subscriptions).find(subscribers(:second).id)
+    subscriber = Subscriber.all.merge!(includes: :subscriptions).find(subscribers(:second).id)
     assert_equal subscriptions, subscriber.subscriptions.sort_by(&:id)
   end
 
@@ -475,32 +485,32 @@ class EagerAssociationTest < ActiveRecord::TestCase
 
     b = Book.create!
 
-    Subscription.create!(:subscriber_id => "PL", :book_id => b.id)
+    Subscription.create!(subscriber_id: "PL", book_id: b.id)
     s.reload
     s.book_ids = s.book_ids
   end
 
   def test_eager_load_has_many_through_with_string_keys
     books = books(:awdr, :rfr)
-    subscriber = Subscriber.all.merge!(:includes => :books).find(subscribers(:second).id)
+    subscriber = Subscriber.all.merge!(includes: :books).find(subscribers(:second).id)
     assert_equal books, subscriber.books.sort_by(&:id)
   end
 
   def test_eager_load_belongs_to_with_string_keys
     subscriber = subscribers(:second)
-    subscription = Subscription.all.merge!(:includes => :subscriber).find(subscriptions(:webster_awdr).id)
+    subscription = Subscription.all.merge!(includes: :subscriber).find(subscriptions(:webster_awdr).id)
     assert_equal subscriber, subscription.subscriber
   end
 
   def test_eager_association_loading_with_explicit_join
-    posts = Post.all.merge!(:includes => :comments, :joins => "INNER JOIN authors ON posts.author_id = authors.id AND authors.name = 'Mary'", :limit => 1, :order => 'author_id').to_a
+    posts = Post.all.merge!(includes: :comments, joins: "INNER JOIN authors ON posts.author_id = authors.id AND authors.name = 'Mary'", limit: 1, order: "author_id").to_a
     assert_equal 1, posts.length
   end
 
   def test_eager_with_has_many_through
-    posts_with_comments = people(:michael).posts.merge(:includes => :comments, :order => 'posts.id').to_a
-    posts_with_author = people(:michael).posts.merge(:includes => :author, :order => 'posts.id').to_a
-    posts_with_comments_and_author = people(:michael).posts.merge(:includes => [ :comments, :author ], :order => 'posts.id').to_a
+    posts_with_comments = people(:michael).posts.merge(includes: :comments, order: "posts.id").to_a
+    posts_with_author = people(:michael).posts.merge(includes: :author, order: "posts.id").to_a
+    posts_with_comments_and_author = people(:michael).posts.merge(includes: [ :comments, :author ], order: "posts.id").to_a
     assert_equal 2, posts_with_comments.inject(0) { |sum, post| sum + post.comments.size }
     assert_equal authors(:david), assert_no_queries { posts_with_author.first.author }
     assert_equal authors(:david), assert_no_queries { posts_with_comments_and_author.first.author }
@@ -508,35 +518,43 @@ class EagerAssociationTest < ActiveRecord::TestCase
 
   def test_eager_with_has_many_through_a_belongs_to_association
     author = authors(:mary)
-    Post.create!(:author => author, :title => "TITLE", :body => "BODY")
-    author.author_favorites.create(:favorite_author_id => 1)
-    author.author_favorites.create(:favorite_author_id => 2)
-    posts_with_author_favorites = author.posts.merge(:includes => :author_favorites).to_a
+    Post.create!(author: author, title: "TITLE", body: "BODY")
+    author.author_favorites.create(favorite_author_id: 1)
+    author.author_favorites.create(favorite_author_id: 2)
+    posts_with_author_favorites = author.posts.merge(includes: :author_favorites).to_a
     assert_no_queries { posts_with_author_favorites.first.author_favorites.first.author_id }
   end
 
   def test_eager_with_has_many_through_an_sti_join_model
-    author = Author.all.merge!(:includes => :special_post_comments, :order => 'authors.id').first
+    author = Author.all.merge!(includes: :special_post_comments, order: "authors.id").first
     assert_equal [comments(:does_it_hurt)], assert_no_queries { author.special_post_comments }
   end
 
+  def test_preloading_has_many_through_with_implicit_source
+    authors = Author.includes(:very_special_comments).to_a
+    assert_no_queries do
+      special_comment_authors = authors.map { |author| [author.name, author.very_special_comments.size] }
+      assert_equal [["David", 1], ["Mary", 0], ["Bob", 0]], special_comment_authors
+    end
+  end
+
   def test_eager_with_has_many_through_an_sti_join_model_with_conditions_on_both
-    author = Author.all.merge!(:includes => :special_nonexistent_post_comments, :order => 'authors.id').first
+    author = Author.all.merge!(includes: :special_nonexistent_post_comments, order: "authors.id").first
     assert_equal [], author.special_nonexistent_post_comments
   end
 
   def test_eager_with_has_many_through_join_model_with_conditions
-    assert_equal Author.all.merge!(:includes => :hello_post_comments,
-                             :order => 'authors.id').first.hello_post_comments.sort_by(&:id),
-                 Author.all.merge!(:order => 'authors.id').first.hello_post_comments.sort_by(&:id)
+    assert_equal Author.all.merge!(includes: :hello_post_comments,
+                             order: "authors.id").first.hello_post_comments.sort_by(&:id),
+                 Author.all.merge!(order: "authors.id").first.hello_post_comments.sort_by(&:id)
   end
 
   def test_eager_with_has_many_through_join_model_with_conditions_on_top_level
-    assert_equal comments(:more_greetings), Author.all.merge!(:includes => :comments_with_order_and_conditions).find(authors(:david).id).comments_with_order_and_conditions.first
+    assert_equal comments(:more_greetings), Author.all.merge!(includes: :comments_with_order_and_conditions).find(authors(:david).id).comments_with_order_and_conditions.first
   end
 
   def test_eager_with_has_many_through_join_model_with_include
-    author_comments = Author.all.merge!(:includes => :comments_with_include).find(authors(:david).id).comments_with_include.to_a
+    author_comments = Author.all.merge!(includes: :comments_with_include).find(authors(:david).id).comments_with_include.to_a
     assert_no_queries do
       author_comments.first.post.title
     end
@@ -544,7 +562,7 @@ class EagerAssociationTest < ActiveRecord::TestCase
 
   def test_eager_with_has_many_through_with_conditions_join_model_with_include
     post_tags = Post.find(posts(:welcome).id).misc_tags
-    eager_post_tags = Post.all.merge!(:includes => :misc_tags).find(1).misc_tags
+    eager_post_tags = Post.all.merge!(includes: :misc_tags).find(1).misc_tags
     assert_equal post_tags, eager_post_tags
   end
 
@@ -555,67 +573,67 @@ class EagerAssociationTest < ActiveRecord::TestCase
   end
 
   def test_eager_with_has_many_and_limit
-    posts = Post.all.merge!(:order => 'posts.id asc', :includes => [ :author, :comments ], :limit => 2).to_a
+    posts = Post.all.merge!(order: "posts.id asc", includes: [ :author, :comments ], limit: 2).to_a
     assert_equal 2, posts.size
     assert_equal 3, posts.inject(0) { |sum, post| sum + post.comments.size }
   end
 
   def test_eager_with_has_many_and_limit_and_conditions
-    posts = Post.all.merge!(:includes => [ :author, :comments ], :limit => 2, :where => "posts.body = 'hello'", :order => "posts.id").to_a
+    posts = Post.all.merge!(includes: [ :author, :comments ], limit: 2, where: "posts.body = 'hello'", order: "posts.id").to_a
     assert_equal 2, posts.size
-    assert_equal [4,5], posts.collect(&:id)
+    assert_equal [4, 5], posts.collect(&:id)
   end
 
   def test_eager_with_has_many_and_limit_and_conditions_array
-    posts = Post.all.merge!(:includes => [ :author, :comments ], :limit => 2, :where => [ "posts.body = ?", 'hello' ], :order => "posts.id").to_a
+    posts = Post.all.merge!(includes: [ :author, :comments ], limit: 2, where: [ "posts.body = ?", "hello" ], order: "posts.id").to_a
     assert_equal 2, posts.size
-    assert_equal [4,5], posts.collect(&:id)
+    assert_equal [4, 5], posts.collect(&:id)
   end
 
   def test_eager_with_has_many_and_limit_and_conditions_array_on_the_eagers
-    posts = Post.includes(:author, :comments).limit(2).references(:author).where("authors.name = ?", 'David')
+    posts = Post.includes(:author, :comments).limit(2).references(:author).where("authors.name = ?", "David")
     assert_equal 2, posts.size
 
-    count = Post.includes(:author, :comments).limit(2).references(:author).where("authors.name = ?", 'David').count
+    count = Post.includes(:author, :comments).limit(2).references(:author).where("authors.name = ?", "David").count
     assert_equal posts.size, count
   end
 
   def test_eager_with_has_many_and_limit_and_high_offset
-    posts = Post.all.merge!(:includes => [ :author, :comments ], :limit => 2, :offset => 10, :where => { 'authors.name' => 'David' }).to_a
+    posts = Post.all.merge!(includes: [ :author, :comments ], limit: 2, offset: 10, where: { "authors.name" => "David" }).to_a
     assert_equal 0, posts.size
   end
 
   def test_eager_with_has_many_and_limit_and_high_offset_and_multiple_array_conditions
     assert_queries(1) do
       posts = Post.references(:authors, :comments).
-        merge(:includes => [ :author, :comments ], :limit => 2, :offset => 10,
-          :where => [ "authors.name = ? and comments.body = ?", 'David', 'go crazy' ]).to_a
+        merge(includes: [ :author, :comments ], limit: 2, offset: 10,
+          where: [ "authors.name = ? and comments.body = ?", "David", "go crazy" ]).to_a
       assert_equal 0, posts.size
     end
   end
 
   def test_eager_with_has_many_and_limit_and_high_offset_and_multiple_hash_conditions
     assert_queries(1) do
-      posts = Post.all.merge!(:includes => [ :author, :comments ], :limit => 2, :offset => 10,
-        :where => { 'authors.name' => 'David', 'comments.body' => 'go crazy' }).to_a
+      posts = Post.all.merge!(includes: [ :author, :comments ], limit: 2, offset: 10,
+        where: { "authors.name" => "David", "comments.body" => "go crazy" }).to_a
       assert_equal 0, posts.size
     end
   end
 
   def test_count_eager_with_has_many_and_limit_and_high_offset
-    posts = Post.all.merge!(:includes => [ :author, :comments ], :limit => 2, :offset => 10, :where => { 'authors.name' => 'David' }).count(:all)
+    posts = Post.all.merge!(includes: [ :author, :comments ], limit: 2, offset: 10, where: { "authors.name" => "David" }).count(:all)
     assert_equal 0, posts
   end
 
   def test_eager_with_has_many_and_limit_with_no_results
-    posts = Post.all.merge!(:includes => [ :author, :comments ], :limit => 2, :where => "posts.title = 'magic forest'").to_a
+    posts = Post.all.merge!(includes: [ :author, :comments ], limit: 2, where: "posts.title = 'magic forest'").to_a
     assert_equal 0, posts.size
   end
 
   def test_eager_count_performed_on_a_has_many_association_with_multi_table_conditional
     author = authors(:david)
     author_posts_without_comments = author.posts.select { |post| post.comments.blank? }
-    assert_equal author_posts_without_comments.size, author.posts.includes(:comments).where('comments.id is null').references(:comments).count
+    assert_equal author_posts_without_comments.size, author.posts.includes(:comments).where("comments.id is null").references(:comments).count
   end
 
   def test_eager_count_performed_on_a_has_many_through_association_with_multi_table_conditional
@@ -625,13 +643,13 @@ class EagerAssociationTest < ActiveRecord::TestCase
   end
 
   def test_eager_with_has_and_belongs_to_many_and_limit
-    posts = Post.all.merge!(:includes => :categories, :order => "posts.id", :limit => 3).to_a
+    posts = Post.all.merge!(includes: :categories, order: "posts.id", limit: 3).to_a
     assert_equal 3, posts.size
     assert_equal 2, posts[0].categories.size
     assert_equal 1, posts[1].categories.size
     assert_equal 0, posts[2].categories.size
-    assert posts[0].categories.include?(categories(:technology))
-    assert posts[1].categories.include?(categories(:general))
+    assert_includes posts[0].categories, categories(:technology)
+    assert_includes posts[1].categories, categories(:general)
   end
 
   # Since the preloader for habtm gets raw row hashes from the database and then
@@ -691,32 +709,32 @@ class EagerAssociationTest < ActiveRecord::TestCase
   end
 
   def test_eager_association_loading_with_habtm
-    posts = Post.all.merge!(:includes => :categories, :order => "posts.id").to_a
+    posts = Post.all.merge!(includes: :categories, order: "posts.id").to_a
     assert_equal 2, posts[0].categories.size
     assert_equal 1, posts[1].categories.size
     assert_equal 0, posts[2].categories.size
-    assert posts[0].categories.include?(categories(:technology))
-    assert posts[1].categories.include?(categories(:general))
+    assert_includes posts[0].categories, categories(:technology)
+    assert_includes posts[1].categories, categories(:general)
   end
 
   def test_eager_with_inheritance
-    SpecialPost.all.merge!(:includes => [ :comments ]).to_a
+    SpecialPost.all.merge!(includes: [ :comments ]).to_a
   end
 
   def test_eager_has_one_with_association_inheritance
-    post = Post.all.merge!(:includes => [ :very_special_comment ]).find(4)
+    post = Post.all.merge!(includes: [ :very_special_comment ]).find(4)
     assert_equal "VerySpecialComment", post.very_special_comment.class.to_s
   end
 
   def test_eager_has_many_with_association_inheritance
-    post = Post.all.merge!(:includes => [ :special_comments ]).find(4)
+    post = Post.all.merge!(includes: [ :special_comments ]).find(4)
     post.special_comments.each do |special_comment|
       assert special_comment.is_a?(SpecialComment)
     end
   end
 
   def test_eager_habtm_with_association_inheritance
-    post = Post.all.merge!(:includes => [ :special_categories ]).find(6)
+    post = Post.all.merge!(includes: [ :special_categories ]).find(6)
     assert_equal 1, post.special_categories.size
     post.special_categories.each do |special_category|
       assert_equal "SpecialCategory", special_category.class.to_s
@@ -725,8 +743,8 @@ class EagerAssociationTest < ActiveRecord::TestCase
 
   def test_eager_with_has_one_dependent_does_not_destroy_dependent
     assert_not_nil companies(:first_firm).account
-    f = Firm.all.merge!(:includes => :account,
-            :where => ["companies.name = ?", "37signals"]).first
+    f = Firm.all.merge!(includes: :account,
+            where: ["companies.name = ?", "37signals"]).first
     assert_not_nil f.account
     assert_equal companies(:first_firm, :reload).account, f.account
   end
@@ -739,38 +757,45 @@ class EagerAssociationTest < ActiveRecord::TestCase
   end
 
   def test_eager_with_invalid_association_reference
-    assert_raise(ActiveRecord::AssociationNotFoundError, "Association was not found; perhaps you misspelled it?  You specified :include => :monkeys") {
-      Post.all.merge!(:includes=> :monkeys ).find(6)
+    e = assert_raise(ActiveRecord::AssociationNotFoundError) {
+      Post.all.merge!(includes: :monkeys).find(6)
     }
-    assert_raise(ActiveRecord::AssociationNotFoundError, "Association was not found; perhaps you misspelled it?  You specified :include => :monkeys") {
-      Post.all.merge!(:includes=>[ :monkeys ]).find(6)
+    assert_equal("Association named 'monkeys' was not found on Post; perhaps you misspelled it?", e.message)
+
+    e = assert_raise(ActiveRecord::AssociationNotFoundError) {
+      Post.all.merge!(includes: [ :monkeys ]).find(6)
     }
-    assert_raise(ActiveRecord::AssociationNotFoundError, "Association was not found; perhaps you misspelled it?  You specified :include => :monkeys") {
-      Post.all.merge!(:includes=>[ 'monkeys' ]).find(6)
+    assert_equal("Association named 'monkeys' was not found on Post; perhaps you misspelled it?", e.message)
+
+    e = assert_raise(ActiveRecord::AssociationNotFoundError) {
+      Post.all.merge!(includes: [ "monkeys" ]).find(6)
     }
-    assert_raise(ActiveRecord::AssociationNotFoundError, "Association was not found; perhaps you misspelled it?  You specified :include => :monkeys, :elephants") {
-      Post.all.merge!(:includes=>[ :monkeys, :elephants ]).find(6)
+    assert_equal("Association named 'monkeys' was not found on Post; perhaps you misspelled it?", e.message)
+
+    e = assert_raise(ActiveRecord::AssociationNotFoundError) {
+      Post.all.merge!(includes: [ :monkeys, :elephants ]).find(6)
     }
+    assert_equal("Association named 'monkeys' was not found on Post; perhaps you misspelled it?", e.message)
   end
 
   def test_eager_has_many_through_with_order
-    tag = OrderedTag.create(name: 'Foo')
-    post1 = Post.create!(title: 'Beaches', body: "I like beaches!")
-    post2 = Post.create!(title: 'Pools', body: "I like pools!")
+    tag = OrderedTag.create(name: "Foo")
+    post1 = Post.create!(title: "Beaches", body: "I like beaches!")
+    post2 = Post.create!(title: "Pools", body: "I like pools!")
 
-    Tagging.create!(taggable_type: 'Post', taggable_id: post1.id, tag: tag)
-    Tagging.create!(taggable_type: 'Post', taggable_id: post2.id, tag: tag)
+    Tagging.create!(taggable_type: "Post", taggable_id: post1.id, tag: tag)
+    Tagging.create!(taggable_type: "Post", taggable_id: post2.id, tag: tag)
 
     tag_with_includes = OrderedTag.includes(:tagged_posts).find(tag.id)
     assert_equal(tag_with_includes.taggings.map(&:taggable).map(&:title), tag_with_includes.tagged_posts.map(&:title))
   end
 
   def test_eager_has_many_through_multiple_with_order
-    tag1 = OrderedTag.create!(name: 'Bar')
-    tag2 = OrderedTag.create!(name: 'Foo')
+    tag1 = OrderedTag.create!(name: "Bar")
+    tag2 = OrderedTag.create!(name: "Foo")
 
-    post1 = Post.create!(title: 'Beaches', body: "I like beaches!")
-    post2 = Post.create!(title: 'Pools', body: "I like pools!")
+    post1 = Post.create!(title: "Beaches", body: "I like beaches!")
+    post2 = Post.create!(title: "Pools", body: "I like pools!")
 
     Tagging.create!(taggable: post1, tag: tag1)
     Tagging.create!(taggable: post2, tag: tag1)
@@ -786,7 +811,7 @@ class EagerAssociationTest < ActiveRecord::TestCase
   end
 
   def test_eager_with_default_scope
-    developer = EagerDeveloperWithDefaultScope.where(:name => 'David').first
+    developer = EagerDeveloperWithDefaultScope.where(name: "David").first
     projects = Project.order(:id).to_a
     assert_no_queries do
       assert_equal(projects, developer.projects)
@@ -794,7 +819,7 @@ class EagerAssociationTest < ActiveRecord::TestCase
   end
 
   def test_eager_with_default_scope_as_class_method
-    developer = EagerDeveloperWithClassMethodDefaultScope.where(:name => 'David').first
+    developer = EagerDeveloperWithClassMethodDefaultScope.where(name: "David").first
     projects = Project.order(:id).to_a
     assert_no_queries do
       assert_equal(projects, developer.projects)
@@ -811,7 +836,7 @@ class EagerAssociationTest < ActiveRecord::TestCase
   end
 
   def test_eager_with_default_scope_as_class_method_using_find_by_method
-    developer = EagerDeveloperWithClassMethodDefaultScope.find_by(name: 'David')
+    developer = EagerDeveloperWithClassMethodDefaultScope.find_by(name: "David")
     projects = Project.order(:id).to_a
     assert_no_queries do
       assert_equal(projects, developer.projects)
@@ -819,7 +844,7 @@ class EagerAssociationTest < ActiveRecord::TestCase
   end
 
   def test_eager_with_default_scope_as_lambda
-    developer = EagerDeveloperWithLambdaDefaultScope.where(:name => 'David').first
+    developer = EagerDeveloperWithLambdaDefaultScope.where(name: "David").first
     projects = Project.order(:id).to_a
     assert_no_queries do
       assert_equal(projects, developer.projects)
@@ -828,8 +853,8 @@ class EagerAssociationTest < ActiveRecord::TestCase
 
   def test_eager_with_default_scope_as_block
     # warm up the habtm cache
-    EagerDeveloperWithBlockDefaultScope.where(:name => 'David').first.projects
-    developer = EagerDeveloperWithBlockDefaultScope.where(:name => 'David').first
+    EagerDeveloperWithBlockDefaultScope.where(name: "David").first.projects
+    developer = EagerDeveloperWithBlockDefaultScope.where(name: "David").first
     projects = Project.order(:id).to_a
     assert_no_queries do
       assert_equal(projects, developer.projects)
@@ -837,30 +862,26 @@ class EagerAssociationTest < ActiveRecord::TestCase
   end
 
   def test_eager_with_default_scope_as_callable
-    developer = EagerDeveloperWithCallableDefaultScope.where(:name => 'David').first
+    developer = EagerDeveloperWithCallableDefaultScope.where(name: "David").first
     projects = Project.order(:id).to_a
     assert_no_queries do
       assert_equal(projects, developer.projects)
     end
   end
 
-  def find_all_ordered(className, include=nil)
-    className.all.merge!(:order=>"#{className.table_name}.#{className.primary_key}", :includes=>include).to_a
-  end
-
   def test_limited_eager_with_order
     assert_equal(
       posts(:thinking, :sti_comments),
       Post.all.merge!(
-        :includes => [:author, :comments], :where => { 'authors.name' => 'David' },
-        :order => 'UPPER(posts.title)', :limit => 2, :offset => 1
+        includes: [:author, :comments], where: { "authors.name" => "David" },
+        order: Arel.sql("UPPER(posts.title)"), limit: 2, offset: 1
       ).to_a
     )
     assert_equal(
       posts(:sti_post_and_comments, :sti_comments),
       Post.all.merge!(
-        :includes => [:author, :comments], :where => { 'authors.name' => 'David' },
-        :order => 'UPPER(posts.title) DESC', :limit => 2, :offset => 1
+        includes: [:author, :comments], where: { "authors.name" => "David" },
+        order: Arel.sql("UPPER(posts.title) DESC"), limit: 2, offset: 1
       ).to_a
     )
   end
@@ -869,15 +890,15 @@ class EagerAssociationTest < ActiveRecord::TestCase
     assert_equal(
       posts(:thinking, :sti_comments),
       Post.all.merge!(
-        :includes => [:author, :comments], :where => { 'authors.name' => 'David' },
-        :order => ['UPPER(posts.title)', 'posts.id'], :limit => 2, :offset => 1
+        includes: [:author, :comments], where: { "authors.name" => "David" },
+        order: [Arel.sql("UPPER(posts.title)"), "posts.id"], limit: 2, offset: 1
       ).to_a
     )
     assert_equal(
       posts(:sti_post_and_comments, :sti_comments),
       Post.all.merge!(
-        :includes => [:author, :comments], :where => { 'authors.name' => 'David' },
-        :order => ['UPPER(posts.title) DESC', 'posts.id'], :limit => 2, :offset => 1
+        includes: [:author, :comments], where: { "authors.name" => "David" },
+        order: [Arel.sql("UPPER(posts.title) DESC"), "posts.id"], limit: 2, offset: 1
       ).to_a
     )
   end
@@ -886,25 +907,25 @@ class EagerAssociationTest < ActiveRecord::TestCase
     assert_equal(
       people(:david, :susan),
       Person.references(:number1_fans_people).merge(
-        :includes => [:readers, :primary_contact, :number1_fan],
-        :where => "number1_fans_people.first_name like 'M%'",
-        :order => 'people.id', :limit => 2, :offset => 0
+        includes: [:readers, :primary_contact, :number1_fan],
+        where: "number1_fans_people.first_name like 'M%'",
+        order: "people.id", limit: 2, offset: 0
       ).to_a
     )
   end
 
   def test_polymorphic_type_condition
-    post = Post.all.merge!(:includes => :taggings).find(posts(:thinking).id)
-    assert post.taggings.include?(taggings(:thinking_general))
-    post = SpecialPost.all.merge!(:includes => :taggings).find(posts(:thinking).id)
-    assert post.taggings.include?(taggings(:thinking_general))
+    post = Post.all.merge!(includes: :taggings).find(posts(:thinking).id)
+    assert_includes post.taggings, taggings(:thinking_general)
+    post = SpecialPost.all.merge!(includes: :taggings).find(posts(:thinking).id)
+    assert_includes post.taggings, taggings(:thinking_general)
   end
 
   def test_eager_with_multiple_associations_with_same_table_has_many_and_habtm
     # Eager includes of has many and habtm associations aren't necessarily sorted in the same way
     def assert_equal_after_sort(item1, item2, item3 = nil)
-      assert_equal(item1.sort{|a,b| a.id <=> b.id}, item2.sort{|a,b| a.id <=> b.id})
-      assert_equal(item3.sort{|a,b| a.id <=> b.id}, item2.sort{|a,b| a.id <=> b.id}) if item3
+      assert_equal(item1.sort { |a, b| a.id <=> b.id }, item2.sort { |a, b| a.id <=> b.id })
+      assert_equal(item3.sort { |a, b| a.id <=> b.id }, item2.sort { |a, b| a.id <=> b.id }) if item3
     end
     # Test regular association, association with conditions, association with
     # STI, and association with conditions assured not to be true
@@ -933,7 +954,11 @@ class EagerAssociationTest < ActiveRecord::TestCase
     d2 = find_all_ordered(Firm, :account)
     d1.each_index do |i|
       assert_equal(d1[i], d2[i])
-      assert_equal(d1[i].account, d2[i].account)
+      if d1[i].account.nil?
+        assert_nil(d2[i].account)
+      else
+        assert_equal(d1[i].account, d2[i].account)
+      end
     end
   end
 
@@ -943,28 +968,34 @@ class EagerAssociationTest < ActiveRecord::TestCase
     d2 = find_all_ordered(Client, firm_types)
     d1.each_index do |i|
       assert_equal(d1[i], d2[i])
-      firm_types.each { |type| assert_equal(d1[i].send(type), d2[i].send(type)) }
+      firm_types.each do |type|
+        if (expected = d1[i].send(type)).nil?
+          assert_nil(d2[i].send(type))
+        else
+          assert_equal(expected, d2[i].send(type))
+        end
+      end
     end
   end
   def test_eager_with_valid_association_as_string_not_symbol
-    assert_nothing_raised { Post.all.merge!(:includes => 'comments').to_a }
+    assert_nothing_raised { Post.all.merge!(includes: "comments").to_a }
   end
 
   def test_eager_with_floating_point_numbers
     assert_queries(2) do
       # Before changes, the floating point numbers will be interpreted as table names and will cause this to run in one query
-      Comment.all.merge!(:where => "123.456 = 123.456", :includes => :post).to_a
+      Comment.all.merge!(where: "123.456 = 123.456", includes: :post).to_a
     end
   end
 
   def test_preconfigured_includes_with_belongs_to
     author = posts(:welcome).author_with_posts
-    assert_no_queries {assert_equal 5, author.posts.size}
+    assert_no_queries { assert_equal 5, author.posts.size }
   end
 
   def test_preconfigured_includes_with_has_one
     comment = posts(:sti_comments).very_special_comment_with_post
-    assert_no_queries {assert_equal posts(:sti_comments), comment.post}
+    assert_no_queries { assert_equal posts(:sti_comments), comment.post }
   end
 
   def test_eager_association_with_scope_with_joins
@@ -1006,13 +1037,13 @@ class EagerAssociationTest < ActiveRecord::TestCase
   end
 
   def test_association_loading_notification
-    notifications = messages_for('instantiation.active_record') do
-      Developer.all.merge!(:includes => 'projects', :where => { 'developers_projects.access_level' => 1 }, :limit => 5).to_a.size
+    notifications = messages_for("instantiation.active_record") do
+      Developer.all.merge!(includes: "projects", where: { "developers_projects.access_level" => 1 }, limit: 5).to_a.size
     end
 
     message = notifications.first
     payload = message.last
-    count = Developer.all.merge!(:includes => 'projects', :where => { 'developers_projects.access_level' => 1 }, :limit => 5).to_a.size
+    count = Developer.all.merge!(includes: "projects", where: { "developers_projects.access_level" => 1 }, limit: 5).to_a.size
 
     # eagerloaded row count should be greater than just developer count
     assert_operator payload[:record_count], :>, count
@@ -1020,7 +1051,7 @@ class EagerAssociationTest < ActiveRecord::TestCase
   end
 
   def test_base_messages
-    notifications = messages_for('instantiation.active_record') do
+    notifications = messages_for("instantiation.active_record") do
       Developer.all.to_a
     end
     message = notifications.first
@@ -1042,61 +1073,55 @@ class EagerAssociationTest < ActiveRecord::TestCase
   end
 
   def test_load_with_sti_sharing_association
-    assert_queries(2) do #should not do 1 query per subclass
+    assert_queries(2) do # should not do 1 query per subclass
       Comment.includes(:post).to_a
     end
   end
 
   def test_conditions_on_join_table_with_include_and_limit
-    assert_equal 3, Developer.all.merge!(:includes => 'projects', :where => { 'developers_projects.access_level' => 1 }, :limit => 5).to_a.size
+    assert_equal 3, Developer.all.merge!(includes: "projects", where: { "developers_projects.access_level" => 1 }, limit: 5).to_a.size
   end
 
   def test_dont_create_temporary_active_record_instances
     Developer.instance_count = 0
-    developers = Developer.all.merge!(:includes => 'projects', :where => { 'developers_projects.access_level' => 1 }, :limit => 5).to_a
+    developers = Developer.all.merge!(includes: "projects", where: { "developers_projects.access_level" => 1 }, limit: 5).to_a
     assert_equal developers.count, Developer.instance_count
   end
 
   def test_order_on_join_table_with_include_and_limit
-    assert_equal 5, Developer.all.merge!(:includes => 'projects', :order => 'developers_projects.joined_on DESC', :limit => 5).to_a.size
+    assert_equal 5, Developer.all.merge!(includes: "projects", order: "developers_projects.joined_on DESC", limit: 5).to_a.size
   end
 
   def test_eager_loading_with_order_on_joined_table_preloads
     posts = assert_queries(2) do
-      Post.all.merge!(:joins => :comments, :includes => :author, :order => 'comments.id DESC').to_a
+      Post.all.merge!(joins: :comments, includes: :author, order: "comments.id DESC").to_a
     end
     assert_equal posts(:eager_other), posts[1]
-    assert_equal authors(:mary), assert_no_queries { posts[1].author}
+    assert_equal authors(:mary), assert_no_queries { posts[1].author }
   end
 
   def test_eager_loading_with_conditions_on_joined_table_preloads
     posts = assert_queries(2) do
-      Post.all.merge!(:select => 'distinct posts.*', :includes => :author, :joins => [:comments], :where => "comments.body like 'Thank you%'", :order => 'posts.id').to_a
+      Post.all.merge!(select: "distinct posts.*", includes: :author, joins: [:comments], where: "comments.body like 'Thank you%'", order: "posts.id").to_a
     end
     assert_equal [posts(:welcome)], posts
-    assert_equal authors(:david), assert_no_queries { posts[0].author}
+    assert_equal authors(:david), assert_no_queries { posts[0].author }
 
     posts = assert_queries(2) do
-      Post.all.merge!(:select => 'distinct posts.*', :includes => :author, :joins => [:comments], :where => "comments.body like 'Thank you%'", :order => 'posts.id').to_a
-    end
-    assert_equal [posts(:welcome)], posts
-    assert_equal authors(:david), assert_no_queries { posts[0].author}
-
-    posts = assert_queries(2) do
-      Post.all.merge!(:includes => :author, :joins => {:taggings => :tag}, :where => "tags.name = 'General'", :order => 'posts.id').to_a
+      Post.all.merge!(includes: :author, joins: { taggings: :tag }, where: "tags.name = 'General'", order: "posts.id").to_a
     end
     assert_equal posts(:welcome, :thinking), posts
 
     posts = assert_queries(2) do
-      Post.all.merge!(:includes => :author, :joins => {:taggings => {:tag => :taggings}}, :where => "taggings_tags.super_tag_id=2", :order => 'posts.id').to_a
+      Post.all.merge!(includes: :author, joins: { taggings: { tag: :taggings } }, where: "taggings_tags.super_tag_id=2", order: "posts.id").to_a
     end
     assert_equal posts(:welcome, :thinking), posts
   end
 
   def test_preload_has_many_with_association_condition_and_default_scope
-    post = Post.create!(:title => 'Beaches', :body => "I like beaches!")
-    Reader.create! :person => people(:david), :post => post
-    LazyReader.create! :person => people(:susan), :post => post
+    post = Post.create!(title: "Beaches", body: "I like beaches!")
+    Reader.create! person: people(:david), post: post
+    LazyReader.create! person: people(:susan), post: post
 
     assert_equal 1, post.lazy_readers.to_a.size
     assert_equal 2, post.lazy_readers_skimmers_or_not.to_a.size
@@ -1107,39 +1132,39 @@ class EagerAssociationTest < ActiveRecord::TestCase
 
   def test_eager_loading_with_conditions_on_string_joined_table_preloads
     posts = assert_queries(2) do
-      Post.all.merge!(:select => 'distinct posts.*', :includes => :author, :joins => "INNER JOIN comments on comments.post_id = posts.id", :where => "comments.body like 'Thank you%'", :order => 'posts.id').to_a
+      Post.all.merge!(select: "distinct posts.*", includes: :author, joins: "INNER JOIN comments on comments.post_id = posts.id", where: "comments.body like 'Thank you%'", order: "posts.id").to_a
     end
     assert_equal [posts(:welcome)], posts
-    assert_equal authors(:david), assert_no_queries { posts[0].author}
+    assert_equal authors(:david), assert_no_queries { posts[0].author }
 
     posts = assert_queries(2) do
-      Post.all.merge!(:select => 'distinct posts.*', :includes => :author, :joins => ["INNER JOIN comments on comments.post_id = posts.id"], :where => "comments.body like 'Thank you%'", :order => 'posts.id').to_a
+      Post.all.merge!(select: "distinct posts.*", includes: :author, joins: ["INNER JOIN comments on comments.post_id = posts.id"], where: "comments.body like 'Thank you%'", order: "posts.id").to_a
     end
     assert_equal [posts(:welcome)], posts
-    assert_equal authors(:david), assert_no_queries { posts[0].author}
+    assert_equal authors(:david), assert_no_queries { posts[0].author }
   end
 
   def test_eager_loading_with_select_on_joined_table_preloads
     posts = assert_queries(2) do
-      Post.all.merge!(:select => 'posts.*, authors.name as author_name', :includes => :comments, :joins => :author, :order => 'posts.id').to_a
+      Post.all.merge!(select: "posts.*, authors.name as author_name", includes: :comments, joins: :author, order: "posts.id").to_a
     end
-    assert_equal 'David', posts[0].author_name
-    assert_equal posts(:welcome).comments, assert_no_queries { posts[0].comments}
+    assert_equal "David", posts[0].author_name
+    assert_equal posts(:welcome).comments, assert_no_queries { posts[0].comments }
   end
 
   def test_eager_loading_with_conditions_on_join_model_preloads
     authors = assert_queries(2) do
-      Author.all.merge!(:includes => :author_address, :joins => :comments, :where => "posts.title like 'Welcome%'").to_a
+      Author.all.merge!(includes: :author_address, joins: :comments, where: "posts.title like 'Welcome%'").to_a
     end
     assert_equal authors(:david), authors[0]
     assert_equal author_addresses(:david_address), authors[0].author_address
   end
 
   def test_preload_belongs_to_uses_exclusive_scope
-    people = Person.males.merge(:includes => :primary_contact).to_a
+    people = Person.males.merge(includes: :primary_contact).to_a
     assert_not_equal people.length, 0
     people.each do |person|
-      assert_no_queries {assert_not_nil person.primary_contact}
+      assert_no_queries { assert_not_nil person.primary_contact }
       assert_equal Person.find(person.id).primary_contact, person.primary_contact
     end
   end
@@ -1163,9 +1188,9 @@ class EagerAssociationTest < ActiveRecord::TestCase
     expected = Firm.find(1).clients_using_primary_key.sort_by(&:name)
     # Oracle adapter truncates alias to 30 characters
     if current_adapter?(:OracleAdapter)
-      firm = Firm.all.merge!(:includes => :clients_using_primary_key, :order => 'clients_using_primary_keys_companies'[0,30]+'.name').find(1)
+      firm = Firm.all.merge!(includes: :clients_using_primary_key, order: "clients_using_primary_keys_companies"[0, 30] + ".name").find(1)
     else
-      firm = Firm.all.merge!(:includes => :clients_using_primary_key, :order => 'clients_using_primary_keys_companies.name').find(1)
+      firm = Firm.all.merge!(includes: :clients_using_primary_key, order: "clients_using_primary_keys_companies.name").find(1)
     end
     assert_no_queries do
       assert_equal expected, firm.clients_using_primary_key
@@ -1174,7 +1199,7 @@ class EagerAssociationTest < ActiveRecord::TestCase
 
   def test_preload_has_one_using_primary_key
     expected = accounts(:signals37)
-    firm = Firm.all.merge!(:includes => :account_using_primary_key, :order => 'companies.id').first
+    firm = Firm.all.merge!(includes: :account_using_primary_key, order: "companies.id").first
     assert_no_queries do
       assert_equal expected, firm.account_using_primary_key
     end
@@ -1182,35 +1207,35 @@ class EagerAssociationTest < ActiveRecord::TestCase
 
   def test_include_has_one_using_primary_key
     expected = accounts(:signals37)
-    firm = Firm.all.merge!(:includes => :account_using_primary_key, :order => 'accounts.id').to_a.detect {|f| f.id == 1}
+    firm = Firm.all.merge!(includes: :account_using_primary_key, order: "accounts.id").to_a.detect { |f| f.id == 1 }
     assert_no_queries do
       assert_equal expected, firm.account_using_primary_key
     end
   end
 
   def test_preloading_empty_belongs_to
-    c = Client.create!(:name => 'Foo', :client_of => Company.maximum(:id) + 1)
+    c = Client.create!(name: "Foo", client_of: Company.maximum(:id) + 1)
 
     client = assert_queries(2) { Client.preload(:firm).find(c.id) }
     assert_no_queries { assert_nil client.firm }
   end
 
   def test_preloading_empty_belongs_to_polymorphic
-    t = Tagging.create!(:taggable_type => 'Post', :taggable_id => Post.maximum(:id) + 1, :tag => tags(:general))
+    t = Tagging.create!(taggable_type: "Post", taggable_id: Post.maximum(:id) + 1, tag: tags(:general))
 
     tagging = assert_queries(2) { Tagging.preload(:taggable).find(t.id) }
     assert_no_queries { assert_nil tagging.taggable }
   end
 
   def test_preloading_through_empty_belongs_to
-    c = Client.create!(:name => 'Foo', :client_of => Company.maximum(:id) + 1)
+    c = Client.create!(name: "Foo", client_of: Company.maximum(:id) + 1)
 
     client = assert_queries(2) { Client.preload(:accounts).find(c.id) }
     assert_no_queries { assert client.accounts.empty? }
   end
 
   def test_preloading_has_many_through_with_distinct
-    mary = Author.includes(:unique_categorized_posts).where(:id => authors(:mary).id).first
+    mary = Author.includes(:unique_categorized_posts).where(id: authors(:mary).id).first
     assert_equal 1, mary.unique_categorized_posts.length
     assert_equal 1, mary.unique_categorized_post_ids.length
   end
@@ -1238,13 +1263,13 @@ class EagerAssociationTest < ActiveRecord::TestCase
     groucho = members(:groucho)
 
     sponsor = assert_queries(2) {
-      Sponsor.includes(:thing).where(:id => sponsor.id).first
+      Sponsor.includes(:thing).where(id: sponsor.id).first
     }
     assert_no_queries { assert_equal groucho, sponsor.thing }
   end
 
   def test_joins_with_includes_should_preload_via_joins
-    post = assert_queries(1) { Post.includes(:comments).joins(:comments).order('posts.id desc').to_a.first }
+    post = assert_queries(1) { Post.includes(:comments).joins(:comments).order("posts.id desc").to_a.first }
 
     assert_queries(0) do
       assert_not_equal 0, post.comments.to_a.count
@@ -1253,16 +1278,16 @@ class EagerAssociationTest < ActiveRecord::TestCase
 
   def test_join_eager_with_empty_order_should_generate_valid_sql
     assert_nothing_raised do
-      Post.includes(:comments).order("").where(:comments => {:body => "Thank you for the welcome"}).first
+      Post.includes(:comments).order("").where(comments: { body: "Thank you for the welcome" }).first
     end
   end
 
   def test_deep_including_through_habtm
     # warm up habtm cache
-    posts = Post.all.merge!(:includes => {:categories => :categorizations}, :order => "posts.id").to_a
+    posts = Post.all.merge!(includes: { categories: :categorizations }, order: "posts.id").to_a
     posts[0].categories[0].categorizations.length
 
-    posts = Post.all.merge!(:includes => {:categories => :categorizations}, :order => "posts.id").to_a
+    posts = Post.all.merge!(includes: { categories: :categorizations }, order: "posts.id").to_a
     assert_no_queries { assert_equal 2, posts[0].categories[0].categorizations.length }
     assert_no_queries { assert_equal 1, posts[0].categories[1].categorizations.length }
     assert_no_queries { assert_equal 2, posts[1].categories[0].categorizations.length }
@@ -1278,20 +1303,25 @@ class EagerAssociationTest < ActiveRecord::TestCase
     assert_equal projects.last.mentor.developers.first.contracts, projects.last.developers.last.contracts
   end
 
+  def test_preloading_has_many_through_with_custom_scope
+    project = Project.includes(:developers_named_david_with_hash_conditions).find(projects(:active_record).id)
+    assert_equal [developers(:david)], project.developers_named_david_with_hash_conditions
+  end
+
   test "scoping with a circular preload" do
-    assert_equal Comment.find(1), Comment.preload(:post => :comments).scoping { Comment.find(1) }
+    assert_equal Comment.find(1), Comment.preload(post: :comments).scoping { Comment.find(1) }
   end
 
   test "circular preload does not modify unscoped" do
     expected = FirstPost.unscoped.find(2)
-    FirstPost.preload(:comments => :first_post).find(1)
+    FirstPost.preload(comments: :first_post).find(1)
     assert_equal expected, FirstPost.unscoped.find(2)
   end
 
   test "preload ignores the scoping" do
     assert_equal(
       Comment.find(1).post,
-      Post.where('1 = 0').scoping { Comment.preload(:post).find(1).post }
+      Post.where("1 = 0").scoping { Comment.preload(:post).find(1).post }
     )
   end
 
@@ -1316,10 +1346,10 @@ class EagerAssociationTest < ActiveRecord::TestCase
   end
 
   test "works in combination with order(:symbol) and reorder(:symbol)" do
-    author = Author.includes(:posts).references(:posts).order(:name).find_by('posts.title IS NOT NULL')
+    author = Author.includes(:posts).references(:posts).order(:name).find_by("posts.title IS NOT NULL")
     assert_equal authors(:bob), author
 
-    author = Author.includes(:posts).references(:posts).reorder(:name).find_by('posts.title IS NOT NULL')
+    author = Author.includes(:posts).references(:posts).reorder(:name).find_by("posts.title IS NOT NULL")
     assert_equal authors(:bob), author
   end
 
@@ -1346,6 +1376,7 @@ class EagerAssociationTest < ActiveRecord::TestCase
     assert_nothing_raised do
       authors(:david).essays.includes(:writer).any?
       authors(:david).essays.includes(:writer).exists?
+      authors(:david).essays.includes(:owner).where("name IS NOT NULL").exists?
     end
   end
 
@@ -1360,7 +1391,7 @@ class EagerAssociationTest < ActiveRecord::TestCase
 
   test "including associations with where.not adds implicit references" do
     author = assert_queries(2) {
-      Author.includes(:posts).where.not(posts: { title: 'Welcome to the weblog'} ).last
+      Author.includes(:posts).where.not(posts: { title: "Welcome to the weblog" }).last
     }
 
     assert_no_queries {
@@ -1394,7 +1425,7 @@ class EagerAssociationTest < ActiveRecord::TestCase
     exception = assert_raises(ArgumentError) do
       Author.preload(10).to_a
     end
-    assert_equal('10 was not recognized for preload', exception.message)
+    assert_equal("10 was not recognized for preload", exception.message)
   end
 
   test "associations with extensions are not instance dependent" do
@@ -1424,6 +1455,24 @@ class EagerAssociationTest < ActiveRecord::TestCase
     assert david.readonly_comments.first.readonly?
   end
 
+  test "eager-loading non-readonly association" do
+    # has_one
+    firm = Firm.where(id: "1").eager_load(:account).first!
+    assert_not firm.account.readonly?
+
+    # has_and_belongs_to_many
+    project = Project.where(id: "2").eager_load(:developers).first!
+    assert_not project.developers.first.readonly?
+
+    # has_many :through
+    david = Author.where(id: "1").eager_load(:comments).first!
+    assert_not david.comments.first.readonly?
+
+    # belongs_to
+    post = Post.where(id: "1").eager_load(:author).first!
+    assert_not post.author.readonly?
+  end
+
   test "eager-loading readonly association" do
     # has-one
     firm = Firm.where(id: "1").eager_load(:readonly_account).first!
@@ -1438,23 +1487,32 @@ class EagerAssociationTest < ActiveRecord::TestCase
     assert david.readonly_comments.first.readonly?
 
     # belongs_to
-    post = Post.where(id: "1").eager_load(:author).first!
-    assert post.author.readonly?
+    post = Post.where(id: "1").eager_load(:readonly_author).first!
+    assert post.readonly_author.readonly?
   end
 
   test "preloading a polymorphic association with references to the associated table" do
-    post = Post.includes(:tags).references(:tags).where('tags.name = ?', 'General').first
+    post = Post.includes(:tags).references(:tags).where("tags.name = ?", "General").first
     assert_equal posts(:welcome), post
   end
 
   test "eager-loading a polymorphic association with references to the associated table" do
-    post = Post.eager_load(:tags).where('tags.name = ?', 'General').first
+    post = Post.eager_load(:tags).where("tags.name = ?", "General").first
     assert_equal posts(:welcome), post
   end
 
+  test "eager-loading with a polymorphic association and using the existential predicate" do
+    assert_equal true, authors(:david).essays.eager_load(:writer).exists?
+  end
+
   # CollectionProxy#reader is expensive, so the preloader avoids calling it.
   test "preloading has_many_through association avoids calling association.reader" do
     ActiveRecord::Associations::HasManyAssociation.any_instance.expects(:reader).never
     Author.preload(:readonly_comments).first!
   end
+
+  private
+    def find_all_ordered(klass, include = nil)
+      klass.order("#{klass.table_name}.#{klass.primary_key}").includes(include).to_a
+    end
 end
diff --git a/activerecord/test/cases/associations/extension_test.rb b/activerecord/test/cases/associations/extension_test.rb
index b161cde335..5eacb5a3d8 100644
--- a/activerecord/test/cases/associations/extension_test.rb
+++ b/activerecord/test/cases/associations/extension_test.rb
@@ -1,10 +1,12 @@
+# frozen_string_literal: true
+
 require "cases/helper"
-require 'models/post'
-require 'models/comment'
-require 'models/project'
-require 'models/developer'
-require 'models/computer'
-require 'models/company_in_module'
+require "models/post"
+require "models/comment"
+require "models/project"
+require "models/developer"
+require "models/computer"
+require "models/company_in_module"
 
 class AssociationsExtensionsTest < ActiveRecord::TestCase
   fixtures :projects, :developers, :developers_projects, :comments, :posts
@@ -36,6 +38,11 @@ class AssociationsExtensionsTest < ActiveRecord::TestCase
     assert_equal comments(:greetings), posts(:welcome).comments.not_again.find_most_recent
   end
 
+  def test_extension_with_dirty_target
+    comment = posts(:welcome).comments.build(body: "New comment")
+    assert_equal comment, posts(:welcome).comments.with_content("New comment")
+  end
+
   def test_marshalling_extensions
     david = developers(:david)
     assert_equal projects(:action_controller), david.projects.find_most_recent
@@ -45,7 +52,7 @@ class AssociationsExtensionsTest < ActiveRecord::TestCase
     # Marshaling an association shouldn't make it unusable by wiping its reflection.
     assert_not_nil david.association(:projects).reflection
 
-    david_too  = Marshal.load(marshalled)
+    david_too = Marshal.load(marshalled)
     assert_equal projects(:action_controller), david_too.projects.find_most_recent
   end
 
@@ -63,19 +70,25 @@ class AssociationsExtensionsTest < ActiveRecord::TestCase
     extend!(Developer)
     extend!(MyApplication::Business::Developer)
 
-    assert Object.const_get 'DeveloperAssociationNameAssociationExtension'
-    assert MyApplication::Business.const_get 'DeveloperAssociationNameAssociationExtension'
+    assert Object.const_get "DeveloperAssociationNameAssociationExtension"
+    assert MyApplication::Business.const_get "DeveloperAssociationNameAssociationExtension"
   end
 
   def test_proxy_association_after_scoped
     post = posts(:welcome)
     assert_equal post.association(:comments), post.comments.the_association
-    assert_equal post.association(:comments), post.comments.where('1=1').the_association
+    assert_equal post.association(:comments), post.comments.where("1=1").the_association
+  end
+
+  def test_association_with_default_scope
+    assert_raises OopsError do
+      posts(:welcome).comments.destroy_all
+    end
   end
 
   private
 
     def extend!(model)
-      ActiveRecord::Associations::Builder::HasMany.define_extensions(model, :association_name) { }
+      ActiveRecord::Associations::Builder::HasMany.define_extensions(model, :association_name) {}
     end
 end
diff --git a/activerecord/test/cases/associations/has_and_belongs_to_many_associations_test.rb b/activerecord/test/cases/associations/has_and_belongs_to_many_associations_test.rb
index 1bbca84bb2..c817d7267b 100644
--- a/activerecord/test/cases/associations/has_and_belongs_to_many_associations_test.rb
+++ b/activerecord/test/cases/associations/has_and_belongs_to_many_associations_test.rb
@@ -1,84 +1,87 @@
+# frozen_string_literal: true
+
 require "cases/helper"
-require 'models/developer'
-require 'models/computer'
-require 'models/project'
-require 'models/company'
-require 'models/course'
-require 'models/customer'
-require 'models/order'
-require 'models/categorization'
-require 'models/category'
-require 'models/post'
-require 'models/author'
-require 'models/tag'
-require 'models/tagging'
-require 'models/parrot'
-require 'models/person'
-require 'models/pirate'
-require 'models/professor'
-require 'models/treasure'
-require 'models/price_estimate'
-require 'models/club'
-require 'models/member'
-require 'models/membership'
-require 'models/sponsor'
-require 'models/country'
-require 'models/treaty'
-require 'models/vertex'
-require 'models/publisher'
-require 'models/publisher/article'
-require 'models/publisher/magazine'
-require 'active_support/core_ext/string/conversions'
+require "models/developer"
+require "models/computer"
+require "models/project"
+require "models/company"
+require "models/course"
+require "models/customer"
+require "models/order"
+require "models/categorization"
+require "models/category"
+require "models/post"
+require "models/author"
+require "models/tag"
+require "models/tagging"
+require "models/parrot"
+require "models/person"
+require "models/pirate"
+require "models/professor"
+require "models/treasure"
+require "models/price_estimate"
+require "models/club"
+require "models/user"
+require "models/member"
+require "models/membership"
+require "models/sponsor"
+require "models/country"
+require "models/treaty"
+require "models/vertex"
+require "models/publisher"
+require "models/publisher/article"
+require "models/publisher/magazine"
+require "active_support/core_ext/string/conversions"
 
 class ProjectWithAfterCreateHook < ActiveRecord::Base
-  self.table_name = 'projects'
+  self.table_name = "projects"
   has_and_belongs_to_many :developers,
-    :class_name => "DeveloperForProjectWithAfterCreateHook",
-    :join_table => "developers_projects",
-    :foreign_key => "project_id",
-    :association_foreign_key => "developer_id"
+    class_name: "DeveloperForProjectWithAfterCreateHook",
+    join_table: "developers_projects",
+    foreign_key: "project_id",
+    association_foreign_key: "developer_id"
 
   after_create :add_david
 
   def add_david
-    david = DeveloperForProjectWithAfterCreateHook.find_by_name('David')
+    david = DeveloperForProjectWithAfterCreateHook.find_by_name("David")
     david.projects << self
   end
 end
 
 class DeveloperForProjectWithAfterCreateHook < ActiveRecord::Base
-  self.table_name = 'developers'
+  self.table_name = "developers"
   has_and_belongs_to_many :projects,
-    :class_name => "ProjectWithAfterCreateHook",
-    :join_table => "developers_projects",
-    :association_foreign_key => "project_id",
-    :foreign_key => "developer_id"
+    class_name: "ProjectWithAfterCreateHook",
+    join_table: "developers_projects",
+    association_foreign_key: "project_id",
+    foreign_key: "developer_id"
 end
 
 class ProjectWithSymbolsForKeys < ActiveRecord::Base
-  self.table_name = 'projects'
+  self.table_name = "projects"
   has_and_belongs_to_many :developers,
-    :class_name => "DeveloperWithSymbolsForKeys",
-    :join_table => :developers_projects,
-    :foreign_key => :project_id,
-    :association_foreign_key => "developer_id"
+    class_name: "DeveloperWithSymbolsForKeys",
+    join_table: :developers_projects,
+    foreign_key: :project_id,
+    association_foreign_key: "developer_id"
 end
 
 class DeveloperWithSymbolsForKeys < ActiveRecord::Base
-  self.table_name = 'developers'
+  self.table_name = "developers"
   has_and_belongs_to_many :projects,
-    :class_name => "ProjectWithSymbolsForKeys",
-    :join_table => :developers_projects,
-    :association_foreign_key => :project_id,
-    :foreign_key => "developer_id"
+    class_name: "ProjectWithSymbolsForKeys",
+    join_table: :developers_projects,
+    association_foreign_key: :project_id,
+    foreign_key: "developer_id"
 end
 
 class SubDeveloper < Developer
-  self.table_name = 'developers'
+  self.table_name = "developers"
   has_and_belongs_to_many :special_projects,
-    :join_table => 'developers_projects',
-    :foreign_key => "project_id",
-    :association_foreign_key => "developer_id"
+    join_table: "developers_projects",
+    foreign_key: "project_id",
+    association_foreign_key: "developer_id"
 end
 
 class DeveloperWithSymbolClassName < Developer
@@ -88,7 +91,7 @@ end
 class DeveloperWithExtendOption < Developer
   module NamedExtension
     def category
-      'sns'
+      "sns"
     end
   end
 
@@ -96,27 +99,42 @@ class DeveloperWithExtendOption < Developer
 end
 
 class ProjectUnscopingDavidDefaultScope < ActiveRecord::Base
-  self.table_name = 'projects'
-  has_and_belongs_to_many :developers, -> { unscope(where: 'name') },
+  self.table_name = "projects"
+  has_and_belongs_to_many :developers, -> { unscope(where: "name") },
     class_name: "LazyBlockDeveloperCalledDavid",
     join_table: "developers_projects",
     foreign_key: "project_id",
     association_foreign_key: "developer_id"
 end
 
+class Kitchen < ActiveRecord::Base
+  has_one :sink
+end
+
+class Sink < ActiveRecord::Base
+  has_and_belongs_to_many :sources, join_table: :edges
+  belongs_to :kitchen
+  accepts_nested_attributes_for :kitchen
+end
+
+class Source < ActiveRecord::Base
+  self.table_name = "men"
+  has_and_belongs_to_many :sinks, join_table: :edges
+end
+
 class HasAndBelongsToManyAssociationsTest < ActiveRecord::TestCase
   fixtures :accounts, :companies, :categories, :posts, :categories_posts, :developers, :projects, :developers_projects,
            :parrots, :pirates, :parrots_pirates, :treasures, :price_estimates, :tags, :taggings, :computers
 
   def setup_data_for_habtm_case
-    ActiveRecord::Base.connection.execute('delete from countries_treaties')
+    ActiveRecord::Base.connection.execute("delete from countries_treaties")
 
-    country = Country.new(:name => 'India')
-    country.country_id = 'c1'
+    country = Country.new(name: "India")
+    country.country_id = "c1"
     country.save!
 
-    treaty = Treaty.new(:name => 'peace')
-    treaty.treaty_id = 't1'
+    treaty = Treaty.new(name: "peace")
+    treaty.treaty_id = "t1"
     country.treaties << treaty
   end
 
@@ -130,33 +148,33 @@ class HasAndBelongsToManyAssociationsTest < ActiveRecord::TestCase
     setup_data_for_habtm_case
 
     con = ActiveRecord::Base.connection
-    sql = 'select * from countries_treaties'
+    sql = "select * from countries_treaties"
     record = con.select_rows(sql).last
-    assert_equal 'c1', record[0]
-    assert_equal 't1', record[1]
+    assert_equal "c1", record[0]
+    assert_equal "t1", record[1]
   end
 
   def test_proper_usage_of_primary_keys_and_join_table
     setup_data_for_habtm_case
 
-    assert_equal 'country_id', Country.primary_key
-    assert_equal 'treaty_id', Treaty.primary_key
+    assert_equal "country_id", Country.primary_key
+    assert_equal "treaty_id", Treaty.primary_key
 
     country = Country.first
     assert_equal 1, country.treaties.count
   end
 
   def test_join_table_composite_primary_key_should_not_warn
-    country = Country.new(:name => 'India')
-    country.country_id = 'c1'
+    country = Country.new(name: "India")
+    country.country_id = "c1"
     country.save!
 
-    treaty = Treaty.new(:name => 'peace')
-    treaty.treaty_id = 't1'
+    treaty = Treaty.new(name: "peace")
+    treaty.treaty_id = "t1"
     warning = capture(:stderr) do
       country.treaties << treaty
     end
-    assert_no_match(/WARNING: Rails does not support composite primary key\./, warning)
+    assert_no_match(/WARNING: Active Record does not support composite primary key\./, warning)
   end
 
   def test_has_and_belongs_to_many
@@ -168,7 +186,7 @@ class HasAndBelongsToManyAssociationsTest < ActiveRecord::TestCase
     active_record = Project.find(1)
     assert !active_record.developers.empty?
     assert_equal 3, active_record.developers.size
-    assert active_record.developers.include?(david)
+    assert_includes active_record.developers, david
   end
 
   def test_adding_single
@@ -248,8 +266,8 @@ class HasAndBelongsToManyAssociationsTest < ActiveRecord::TestCase
     assert !p.persisted?
     assert aredridel.save
     assert aredridel.persisted?
-    assert_equal no_of_devels+1, Developer.count
-    assert_equal no_of_projects+1, Project.count
+    assert_equal no_of_devels + 1, Developer.count
+    assert_equal no_of_projects + 1, Project.count
     assert_equal 2, aredridel.projects.size
     assert_equal 2, aredridel.projects.reload.size
   end
@@ -257,7 +275,7 @@ class HasAndBelongsToManyAssociationsTest < ActiveRecord::TestCase
   def test_habtm_saving_multiple_relationships
     new_project = Project.new("name" => "Grimetime")
     amount_of_developers = 4
-    developers = (0...amount_of_developers).collect {|i| Developer.create(:name => "JME #{i}") }.reverse
+    developers = (0...amount_of_developers).collect { |i| Developer.create(name: "JME #{i}") }.reverse
 
     new_project.developer_ids = [developers[0].id, developers[1].id]
     new_project.developers_with_callback_ids = [developers[2].id, developers[3].id]
@@ -282,11 +300,10 @@ class HasAndBelongsToManyAssociationsTest < ActiveRecord::TestCase
   end
 
   def test_habtm_collection_size_from_params
-    devel = Developer.new({
+    devel = Developer.new(
       projects_attributes: {
-        '0' => {}
-      }
-    })
+        "0" => {}
+      })
 
     assert_equal 1, devel.projects.size
   end
@@ -322,9 +339,9 @@ class HasAndBelongsToManyAssociationsTest < ActiveRecord::TestCase
   end
 
   def test_build_by_new_record
-    devel = Developer.new(:name => "Marcel", :salary => 75000)
-    devel.projects.build(:name => "Make bed")
-    proj2 = devel.projects.build(:name => "Lie in it")
+    devel = Developer.new(name: "Marcel", salary: 75000)
+    devel.projects.build(name: "Make bed")
+    proj2 = devel.projects.build(name: "Lie in it")
     assert_equal devel.projects.last, proj2
     assert !proj2.persisted?
     devel.save
@@ -346,31 +363,18 @@ class HasAndBelongsToManyAssociationsTest < ActiveRecord::TestCase
     assert_equal Developer.find(1).projects.sort_by(&:id).last, proj  # prove join table is updated
   end
 
-  def test_create_by_new_record
-    devel = Developer.new(:name => "Marcel", :salary => 75000)
-    devel.projects.build(:name => "Make bed")
-    proj2 = devel.projects.build(:name => "Lie in it")
-    assert_equal devel.projects.last, proj2
-    assert !proj2.persisted?
-    devel.save
-    assert devel.persisted?
-    assert proj2.persisted?
-    assert_equal devel.projects.last, proj2
-    assert_equal Developer.find_by_name("Marcel").projects.last, proj2  # prove join table is updated
-  end
-
   def test_creation_respects_hash_condition
     # in Oracle '' is saved as null therefore need to save ' ' in not null column
-    post = categories(:general).post_with_conditions.build(:body => ' ')
+    post = categories(:general).post_with_conditions.build(body: " ")
 
     assert        post.save
-    assert_equal  'Yet Another Testing Title', post.title
+    assert_equal  "Yet Another Testing Title", post.title
 
     # in Oracle '' is saved as null therefore need to save ' ' in not null column
-    another_post = categories(:general).post_with_conditions.create(:body => ' ')
+    another_post = categories(:general).post_with_conditions.create(body: " ")
 
     assert        another_post.persisted?
-    assert_equal  'Yet Another Testing Title', another_post.title
+    assert_equal  "Yet Another Testing Title", another_post.title
   end
 
   def test_distinct_after_the_fact
@@ -379,7 +383,7 @@ class HasAndBelongsToManyAssociationsTest < ActiveRecord::TestCase
     dev.projects << projects(:active_record)
 
     assert_equal 3, dev.projects.size
-    assert_equal 1, dev.projects.distinct.size
+    assert_equal 1, dev.projects.uniq.size
   end
 
   def test_distinct_before_the_fact
@@ -544,7 +548,7 @@ class HasAndBelongsToManyAssociationsTest < ActiveRecord::TestCase
 
     assert_no_queries(ignore_none: false) do
       assert project.developers.loaded?
-      assert project.developers.include?(developer)
+      assert_includes project.developers, developer
     end
   end
 
@@ -555,14 +559,14 @@ class HasAndBelongsToManyAssociationsTest < ActiveRecord::TestCase
     project.reload
     assert ! project.developers.loaded?
     assert_queries(1) do
-      assert project.developers.include?(developer)
+      assert_includes project.developers, developer
     end
     assert ! project.developers.loaded?
   end
 
   def test_include_returns_false_for_non_matching_record_to_verify_scoping
     project = projects(:active_record)
-    developer = Developer.create :name => "Bryan", :salary => 50_000
+    developer = Developer.create name: "Bryan", salary: 50_000
 
     assert ! project.developers.loaded?
     assert ! project.developers.include?(developer)
@@ -576,32 +580,32 @@ class HasAndBelongsToManyAssociationsTest < ActiveRecord::TestCase
 
   def test_dynamic_find_should_respect_association_order
     # Developers are ordered 'name DESC, id DESC'
-    high_id_jamis = projects(:active_record).developers.create(:name => 'Jamis')
+    high_id_jamis = projects(:active_record).developers.create(name: "Jamis")
 
-    assert_equal high_id_jamis, projects(:active_record).developers.merge(:where => "name = 'Jamis'").first
-    assert_equal high_id_jamis, projects(:active_record).developers.find_by_name('Jamis')
+    assert_equal high_id_jamis, projects(:active_record).developers.merge(where: "name = 'Jamis'").first
+    assert_equal high_id_jamis, projects(:active_record).developers.find_by_name("Jamis")
   end
 
   def test_find_should_append_to_association_order
-    ordered_developers = projects(:active_record).developers.order('projects.id')
-    assert_equal ['developers.name desc, developers.id desc', 'projects.id'], ordered_developers.order_values
+    ordered_developers = projects(:active_record).developers.order("projects.id")
+    assert_equal ["developers.name desc, developers.id desc", "projects.id"], ordered_developers.order_values
   end
 
   def test_dynamic_find_all_should_respect_readonly_access
-    projects(:active_record).readonly_developers.each { |d| assert_raise(ActiveRecord::ReadOnlyRecord) { d.save!  } if d.valid?}
+    projects(:active_record).readonly_developers.each { |d| assert_raise(ActiveRecord::ReadOnlyRecord) { d.save!  } if d.valid? }
     projects(:active_record).readonly_developers.each(&:readonly?)
   end
 
   def test_new_with_values_in_collection
-    jamis = DeveloperForProjectWithAfterCreateHook.find_by_name('Jamis')
-    david = DeveloperForProjectWithAfterCreateHook.find_by_name('David')
-    project = ProjectWithAfterCreateHook.new(:name => "Cooking with Bertie")
+    jamis = DeveloperForProjectWithAfterCreateHook.find_by_name("Jamis")
+    david = DeveloperForProjectWithAfterCreateHook.find_by_name("David")
+    project = ProjectWithAfterCreateHook.new(name: "Cooking with Bertie")
     project.developers << jamis
     project.save!
     project.reload
 
-    assert project.developers.include?(jamis)
-    assert project.developers.include?(david)
+    assert_includes project.developers, jamis
+    assert_includes project.developers, david
   end
 
   def test_find_in_association_with_options
@@ -612,8 +616,8 @@ class HasAndBelongsToManyAssociationsTest < ActiveRecord::TestCase
   end
 
   def test_association_with_extend_option
-    eponine = DeveloperWithExtendOption.create(name: 'Eponine')
-    assert_equal 'sns', eponine.projects.category
+    eponine = DeveloperWithExtendOption.create(name: "Eponine")
+    assert_equal "sns", eponine.projects.category
   end
 
   def test_replace_with_less
@@ -628,7 +632,7 @@ class HasAndBelongsToManyAssociationsTest < ActiveRecord::TestCase
     david.projects = [projects(:action_controller), Project.new("name" => "ActionWebSearch")]
     david.save
     assert_equal 2, david.projects.length
-    assert !david.projects.include?(projects(:active_record))
+    assert_not_includes david.projects, projects(:active_record)
   end
 
   def test_replace_on_new_object
@@ -646,9 +650,9 @@ class HasAndBelongsToManyAssociationsTest < ActiveRecord::TestCase
     developer.special_projects << special_project
     developer.reload
 
-    assert developer.projects.include?(special_project)
-    assert developer.special_projects.include?(special_project)
-    assert !developer.special_projects.include?(other_project)
+    assert_includes developer.projects, special_project
+    assert_includes developer.special_projects, special_project
+    assert_not_includes developer.special_projects, other_project
   end
 
   def test_symbol_join_table
@@ -689,7 +693,7 @@ class HasAndBelongsToManyAssociationsTest < ActiveRecord::TestCase
   end
 
   def test_habtm_respects_select_query_method
-    assert_equal ['id'], developers(:david).projects.select(:id).first.attributes.keys
+    assert_equal ["id"], developers(:david).projects.select(:id).first.attributes.keys
   end
 
   def test_join_table_alias
@@ -700,8 +704,8 @@ class HasAndBelongsToManyAssociationsTest < ActiveRecord::TestCase
     assert_equal(
       3,
       Developer.references(:developers_projects_join).merge(
-        :includes => {:projects => :developers},
-        :where => 'projects_developers_projects_join.joined_on IS NOT NULL'
+        includes: { projects: :developers },
+        where: "projects_developers_projects_join.joined_on IS NOT NULL"
       ).to_a.size
     )
   end
@@ -720,15 +724,15 @@ class HasAndBelongsToManyAssociationsTest < ActiveRecord::TestCase
     assert_equal(
       3,
       Developer.references(:developers_projects_join).merge(
-        :includes => {:projects => :developers}, :where => 'projects_developers_projects_join.joined_on IS NOT NULL',
-        :group => group.join(",")
+        includes: { projects: :developers }, where: "projects_developers_projects_join.joined_on IS NOT NULL",
+        group: group.join(",")
       ).to_a.size
     )
   end
 
   def test_find_grouped
-    all_posts_from_category1 = Post.all.merge!(:where => "category_id = 1", :joins => :categories).to_a
-    grouped_posts_of_category1 = Post.all.merge!(:where => "category_id = 1", :group => "author_id", :select => 'count(posts.id) as posts_count', :joins => :categories).to_a
+    all_posts_from_category1 = Post.all.merge!(where: "category_id = 1", joins: :categories).to_a
+    grouped_posts_of_category1 = Post.all.merge!(where: "category_id = 1", group: "author_id", select: "count(posts.id) as posts_count", joins: :categories).to_a
     assert_equal 5, all_posts_from_category1.size
     assert_equal 2, grouped_posts_of_category1.size
   end
@@ -739,8 +743,8 @@ class HasAndBelongsToManyAssociationsTest < ActiveRecord::TestCase
   end
 
   def test_find_scoped_grouped_having
-    assert_equal 2, projects(:active_record).well_payed_salary_groups.to_a.size
-    assert projects(:active_record).well_payed_salary_groups.all? { |g| g.salary > 10000 }
+    assert_equal 2, projects(:active_record).well_paid_salary_groups.to_a.size
+    assert projects(:active_record).well_paid_salary_groups.all? { |g| g.salary > 10000 }
   end
 
   def test_get_ids
@@ -775,7 +779,7 @@ class HasAndBelongsToManyAssociationsTest < ActiveRecord::TestCase
 
   def test_assign_ids_ignoring_blanks
     developer = Developer.new("name" => "Joe")
-    developer.project_ids = [projects(:active_record).id, nil, projects(:action_controller).id, '']
+    developer.project_ids = [projects(:active_record).id, nil, projects(:action_controller).id, ""]
     developer.save
     developer.reload
     assert_equal 2, developer.projects.length
@@ -795,8 +799,8 @@ class HasAndBelongsToManyAssociationsTest < ActiveRecord::TestCase
   end
 
   def test_symbols_as_keys
-    developer = DeveloperWithSymbolsForKeys.new(:name => 'David')
-    project = ProjectWithSymbolsForKeys.new(:name => 'Rails Testing')
+    developer = DeveloperWithSymbolsForKeys.new(name: "David")
+    project = ProjectWithSymbolsForKeys.new(name: "Rails Testing")
     project.developers << developer
     project.save!
 
@@ -809,7 +813,7 @@ class HasAndBelongsToManyAssociationsTest < ActiveRecord::TestCase
   def test_dynamic_find_should_respect_association_include
     # SQL error in sort clause if :include is not included
     # due to Unknown column 'authors.id'
-    assert Category.find(1).posts_with_authors_sorted_by_author_id.find_by_title('Welcome to the weblog')
+    assert Category.find(1).posts_with_authors_sorted_by_author_id.find_by_title("Welcome to the weblog")
   end
 
   def test_count
@@ -841,12 +845,12 @@ class HasAndBelongsToManyAssociationsTest < ActiveRecord::TestCase
   end
 
   def test_attributes_are_being_set_when_initialized_from_habtm_association_with_where_clause
-    new_developer = projects(:action_controller).developers.where(:name => "Marcelo").build
+    new_developer = projects(:action_controller).developers.where(name: "Marcelo").build
     assert_equal new_developer.name, "Marcelo"
   end
 
   def test_attributes_are_being_set_when_initialized_from_habtm_association_with_multiple_where_clauses
-    new_developer = projects(:action_controller).developers.where(:name => "Marcelo").where(:salary => 90_000).build
+    new_developer = projects(:action_controller).developers.where(name: "Marcelo").where(salary: 90_000).build
     assert_equal new_developer.name, "Marcelo"
     assert_equal new_developer.salary, 90_000
   end
@@ -854,7 +858,7 @@ class HasAndBelongsToManyAssociationsTest < ActiveRecord::TestCase
   def test_include_method_in_has_and_belongs_to_many_association_should_return_true_for_instance_added_with_build
     project = Project.new
     developer = project.developers.build
-    assert project.developers.include?(developer)
+    assert_includes project.developers, developer
   end
 
   def test_destruction_does_not_error_without_primary_key
@@ -871,7 +875,7 @@ class HasAndBelongsToManyAssociationsTest < ActiveRecord::TestCase
     projects = Developer.new.projects
     assert_no_queries(ignore_none: false) do
       assert_equal [], projects
-      assert_equal [], projects.where(title: 'omg')
+      assert_equal [], projects.where(title: "omg")
       assert_equal [], projects.pluck(:title)
       assert_equal 0, projects.count
     end
@@ -885,7 +889,7 @@ class HasAndBelongsToManyAssociationsTest < ActiveRecord::TestCase
     treasure.valid?
 
     assert_equal 1, treasure.rich_people.size
-    assert_nil rich_person.first_name, 'should not run associated person validation on create when validate: false'
+    assert_nil rich_person.first_name, "should not run associated person validation on create when validate: false"
   end
 
   def test_association_with_validate_false_does_not_run_associated_validation_callbacks_on_update
@@ -898,11 +902,11 @@ class HasAndBelongsToManyAssociationsTest < ActiveRecord::TestCase
     treasure.valid?
 
     assert_equal 1, treasure.rich_people.size
-    assert_equal person_first_name, rich_person.first_name, 'should not run associated person validation on update when validate: false'
+    assert_equal person_first_name, rich_person.first_name, "should not run associated person validation on update when validate: false"
   end
 
   def test_custom_join_table
-    assert_equal 'edges', Vertex.reflect_on_association(:sources).join_table
+    assert_equal "edges", Vertex.reflect_on_association(:sources).join_table
   end
 
   def test_has_and_belongs_to_many_in_a_namespaced_model_pointing_to_a_namespaced_model
@@ -926,29 +930,24 @@ class HasAndBelongsToManyAssociationsTest < ActiveRecord::TestCase
   def test_redefine_habtm
     child = SubDeveloper.new("name" => "Aredridel")
     child.special_projects << SpecialProject.new("name" => "Special Project")
-    assert child.save, 'child object should be saved'
+    assert child.save, "child object should be saved"
   end
 
   def test_habtm_with_reflection_using_class_name_and_fixtures
-    assert_not_nil Developer._reflections['shared_computers']
+    assert_not_nil Developer._reflections["shared_computers"]
     # Checking the fixture for named association is important here, because it's the only way
     # we've been able to reproduce this bug
-    assert_not_nil File.read(File.expand_path("../../../fixtures/developers.yml", __FILE__)).index("shared_computers")
+    assert_not_nil File.read(File.expand_path("../../fixtures/developers.yml", __dir__)).index("shared_computers")
     assert_equal developers(:david).shared_computers.first, computers(:laptop)
   end
 
   def test_with_symbol_class_name
     assert_nothing_raised do
-      DeveloperWithSymbolClassName.new
+      developer = DeveloperWithSymbolClassName.new
+      developer.projects
     end
   end
 
-  def test_association_force_reload_with_only_true_is_deprecated
-    developer = Developer.find(1)
-
-    assert_deprecated { developer.projects(true) }
-  end
-
   def test_alternate_database
     professor = Professor.create(name: "Plum")
     course = Course.create(name: "Forensics")
@@ -995,4 +994,27 @@ class HasAndBelongsToManyAssociationsTest < ActiveRecord::TestCase
       Project.first.developers_required_by_default.create!(name: "Sean", salary: 50000)
     end
   end
+
+  def test_association_name_is_the_same_as_join_table_name
+    user = User.create!
+    assert_nothing_raised { user.jobs_pool.clear }
+  end
+
+  def test_has_and_belongs_to_many_while_partial_writes_false
+    begin
+      original_partial_writes = ActiveRecord::Base.partial_writes
+      ActiveRecord::Base.partial_writes = false
+      developer = Developer.new(name: "Mehmet Emin İNAÇ")
+      developer.projects << Project.new(name: "Bounty")
+
+      assert developer.save
+    ensure
+      ActiveRecord::Base.partial_writes = original_partial_writes
+    end
+  end
+
+  def test_has_and_belongs_to_many_with_belongs_to
+    sink = Sink.create! kitchen: Kitchen.new, sources: [Source.new]
+    assert_equal 1, sink.sources.count
+  end
 end
diff --git a/activerecord/test/cases/associations/has_many_associations_test.rb b/activerecord/test/cases/associations/has_many_associations_test.rb
index 7ec0dfce7a..18548f8516 100644
--- a/activerecord/test/cases/associations/has_many_associations_test.rb
+++ b/activerecord/test/cases/associations/has_many_associations_test.rb
@@ -1,90 +1,103 @@
+# frozen_string_literal: true
+
 require "cases/helper"
-require 'models/developer'
-require 'models/computer'
-require 'models/project'
-require 'models/company'
-require 'models/contract'
-require 'models/topic'
-require 'models/reply'
-require 'models/category'
-require 'models/image'
-require 'models/post'
-require 'models/author'
-require 'models/essay'
-require 'models/comment'
-require 'models/person'
-require 'models/reader'
-require 'models/tagging'
-require 'models/tag'
-require 'models/invoice'
-require 'models/line_item'
-require 'models/car'
-require 'models/bulb'
-require 'models/engine'
-require 'models/categorization'
-require 'models/minivan'
-require 'models/speedometer'
-require 'models/reference'
-require 'models/job'
-require 'models/college'
-require 'models/student'
-require 'models/pirate'
-require 'models/ship'
-require 'models/ship_part'
-require 'models/treasure'
-require 'models/parrot'
-require 'models/tyre'
-require 'models/subscriber'
-require 'models/subscription'
-require 'models/zine'
-require 'models/interest'
+require "models/developer"
+require "models/computer"
+require "models/project"
+require "models/company"
+require "models/contract"
+require "models/topic"
+require "models/reply"
+require "models/category"
+require "models/image"
+require "models/post"
+require "models/author"
+require "models/essay"
+require "models/comment"
+require "models/person"
+require "models/reader"
+require "models/tagging"
+require "models/tag"
+require "models/invoice"
+require "models/line_item"
+require "models/car"
+require "models/bulb"
+require "models/engine"
+require "models/categorization"
+require "models/minivan"
+require "models/speedometer"
+require "models/reference"
+require "models/job"
+require "models/college"
+require "models/student"
+require "models/pirate"
+require "models/ship"
+require "models/ship_part"
+require "models/treasure"
+require "models/parrot"
+require "models/tyre"
+require "models/subscriber"
+require "models/subscription"
+require "models/zine"
+require "models/interest"
 
 class HasManyAssociationsTestForReorderWithJoinDependency < ActiveRecord::TestCase
-  fixtures :authors, :posts, :comments
+  fixtures :authors, :author_addresses, :posts, :comments
 
   def test_should_generate_valid_sql
     author = authors(:david)
     # this can fail on adapters which require ORDER BY expressions to be included in the SELECT expression
     # if the reorder clauses are not correctly handled
-    assert author.posts_with_comments_sorted_by_comment_id.where('comments.id > 0').reorder('posts.comments_count DESC', 'posts.tags_count DESC').last
+    assert author.posts_with_comments_sorted_by_comment_id.where("comments.id > 0").reorder("posts.comments_count DESC", "posts.tags_count DESC").last
   end
 end
 
 class HasManyAssociationsTestPrimaryKeys < ActiveRecord::TestCase
-  fixtures :authors, :essays, :subscribers, :subscriptions, :people
+  fixtures :authors, :author_addresses, :essays, :subscribers, :subscriptions, :people
 
   def test_custom_primary_key_on_new_record_should_fetch_with_query
-    subscriber = Subscriber.new(nick: 'webster132')
+    subscriber = Subscriber.new(nick: "webster132")
     assert !subscriber.subscriptions.loaded?
 
     assert_queries 1 do
       assert_equal 2, subscriber.subscriptions.size
     end
 
-    assert_equal subscriber.subscriptions, Subscription.where(subscriber_id: 'webster132')
+    assert_equal Subscription.where(subscriber_id: "webster132"), subscriber.subscriptions
   end
 
   def test_association_primary_key_on_new_record_should_fetch_with_query
-    author = Author.new(:name => "David")
+    author = Author.new(name: "David")
     assert !author.essays.loaded?
 
     assert_queries 1 do
       assert_equal 1, author.essays.size
     end
 
-    assert_equal author.essays, Essay.where(writer_id: "David")
+    assert_equal Essay.where(writer_id: "David"), author.essays
   end
 
   def test_has_many_custom_primary_key
     david = authors(:david)
-    assert_equal david.essays, Essay.where(writer_id: "David")
+    assert_equal Essay.where(writer_id: "David"), david.essays
+  end
+
+  def test_ids_on_unloaded_association_with_custom_primary_key
+    david = people(:david)
+    assert_equal Essay.where(writer_id: "David").pluck(:id), david.essay_ids
+  end
+
+  def test_ids_on_loaded_association_with_custom_primary_key
+    david = people(:david)
+    david.essays.load
+    assert_equal Essay.where(writer_id: "David").pluck(:id), david.essay_ids
   end
 
   def test_has_many_assignment_with_custom_primary_key
     david = people(:david)
 
     assert_equal ["A Modest Proposal"], david.essays.map(&:name)
-    david.essays = [Essay.create!(name: "Remote Work" )]
+    david.essays = [Essay.create!(name: "Remote Work")]
     assert_equal ["Remote Work"], david.essays.map(&:name)
   end
 
@@ -100,7 +113,7 @@ end
 
 class HasManyAssociationsTest < ActiveRecord::TestCase
   fixtures :accounts, :categories, :companies, :developers, :projects,
-           :developers_projects, :topics, :authors, :comments,
+           :developers_projects, :topics, :authors, :author_addresses, :comments,
            :posts, :readers, :taggings, :cars, :jobs, :tags,
            :categorizations, :zines, :interests
 
@@ -116,14 +129,14 @@ class HasManyAssociationsTest < ActiveRecord::TestCase
 
   def test_anonymous_has_many
     developer = Class.new(ActiveRecord::Base) {
-      self.table_name = 'developers'
+      self.table_name = "developers"
       dev = self
 
       developer_project = Class.new(ActiveRecord::Base) {
-        self.table_name = 'developers_projects'
-        belongs_to :developer, :anonymous_class => dev
+        self.table_name = "developers_projects"
+        belongs_to :developer, anonymous_class: dev
       }
-      has_many :developer_projects, :anonymous_class => developer_project, :foreign_key => 'developer_id'
+      has_many :developer_projects, anonymous_class: developer_project, foreign_key: "developer_id"
     }
     dev = developer.first
     named = Developer.find(dev.id)
@@ -135,20 +148,20 @@ class HasManyAssociationsTest < ActiveRecord::TestCase
   def test_default_scope_on_relations_is_not_cached
     counter = 0
     posts = Class.new(ActiveRecord::Base) {
-      self.table_name = 'posts'
-      self.inheritance_column = 'not_there'
+      self.table_name = "posts"
+      self.inheritance_column = "not_there"
       post = self
 
       comments = Class.new(ActiveRecord::Base) {
-        self.table_name = 'comments'
-        self.inheritance_column = 'not_there'
-        belongs_to :post, :anonymous_class => post
+        self.table_name = "comments"
+        self.inheritance_column = "not_there"
+        belongs_to :post, anonymous_class: post
         default_scope -> {
           counter += 1
-          where("id = :inc", :inc => counter)
+          where("id = :inc", inc: counter)
         }
       }
-      has_many :comments, :anonymous_class => comments, :foreign_key => 'post_id'
+      has_many :comments, anonymous_class: comments, foreign_key: "post_id"
     }
     assert_equal 0, counter
     post = posts.first
@@ -159,15 +172,15 @@ class HasManyAssociationsTest < ActiveRecord::TestCase
   end
 
   def test_has_many_build_with_options
-    college = College.create(name: 'UFMT')
-    Student.create(active: true, college_id: college.id, name: 'Sarah')
+    college = College.create(name: "UFMT")
+    Student.create(active: true, college_id: college.id, name: "Sarah")
 
     assert_equal college.students, Student.where(active: true, college_id: college.id)
   end
 
   def test_add_record_to_collection_should_change_its_updated_at
-    ship = Ship.create(name: 'dauntless')
-    part = ShipPart.create(name: 'cockpit')
+    ship = Ship.create(name: "dauntless")
+    part = ShipPart.create(name: "cockpit")
     updated_at = part.updated_at
 
     travel(1.second) do
@@ -181,38 +194,38 @@ class HasManyAssociationsTest < ActiveRecord::TestCase
   def test_clear_collection_should_not_change_updated_at
     # GH#17161: .clear calls delete_all (and returns the association),
     # which is intended to not touch associated objects's updated_at field
-    ship = Ship.create(name: 'dauntless')
-    part = ShipPart.create(name: 'cockpit', ship_id: ship.id)
+    ship = Ship.create(name: "dauntless")
+    part = ShipPart.create(name: "cockpit", ship_id: ship.id)
 
     ship.parts.clear
     part.reload
 
-    assert_equal nil, part.ship
+    assert_nil part.ship
     assert !part.updated_at_changed?
   end
 
   def test_create_from_association_should_respect_default_scope
-    car = Car.create(:name => 'honda')
-    assert_equal 'honda', car.name
+    car = Car.create(name: "honda")
+    assert_equal "honda", car.name
 
     bulb = Bulb.create
-    assert_equal 'defaulty', bulb.name
+    assert_equal "defaulty", bulb.name
 
     bulb = car.bulbs.build
-    assert_equal 'defaulty', bulb.name
+    assert_equal "defaulty", bulb.name
 
     bulb = car.bulbs.create
-    assert_equal 'defaulty', bulb.name
+    assert_equal "defaulty", bulb.name
   end
 
   def test_build_and_create_from_association_should_respect_passed_attributes_over_default_scope
-    car = Car.create(name: 'honda')
+    car = Car.create(name: "honda")
 
-    bulb = car.bulbs.build(name: 'exotic')
-    assert_equal 'exotic', bulb.name
+    bulb = car.bulbs.build(name: "exotic")
+    assert_equal "exotic", bulb.name
 
-    bulb = car.bulbs.create(name: 'exotic')
-    assert_equal 'exotic', bulb.name
+    bulb = car.bulbs.create(name: "exotic")
+    assert_equal "exotic", bulb.name
 
     bulb = car.awesome_bulbs.build(frickinawesome: false)
     assert_equal false, bulb.frickinawesome
@@ -225,36 +238,44 @@ class HasManyAssociationsTest < ActiveRecord::TestCase
     author = Author.new
 
     post = author.thinking_posts.build
-    assert_equal 'So I was thinking', post.title
+    assert_equal "So I was thinking", post.title
   end
 
   def test_create_from_association_with_nil_values_should_work
-    car = Car.create(:name => 'honda')
+    car = Car.create(name: "honda")
 
     bulb = car.bulbs.new(nil)
-    assert_equal 'defaulty', bulb.name
+    assert_equal "defaulty", bulb.name
 
     bulb = car.bulbs.build(nil)
-    assert_equal 'defaulty', bulb.name
+    assert_equal "defaulty", bulb.name
 
     bulb = car.bulbs.create(nil)
-    assert_equal 'defaulty', bulb.name
+    assert_equal "defaulty", bulb.name
+  end
+
+  def test_build_from_association_sets_inverse_instance
+    car = Car.new(name: "honda")
+
+    bulb = car.bulbs.build
+    assert_equal car, bulb.car
   end
 
   def test_do_not_call_callbacks_for_delete_all
-    car = Car.create(:name => 'honda')
+    car = Car.create(name: "honda")
     car.funky_bulbs.create!
+    assert_equal 1, car.funky_bulbs.count
     assert_nothing_raised { car.reload.funky_bulbs.delete_all }
-    assert_equal 0, Bulb.count, "bulbs should have been deleted using :delete_all strategy"
+    assert_equal 0, car.funky_bulbs.count, "bulbs should have been deleted using :delete_all strategy"
   end
 
   def test_delete_all_on_association_is_the_same_as_not_loaded
     author = authors :david
-    author.thinking_posts.create!(:body => "test")
+    author.thinking_posts.create!(body: "test")
     author.reload
     expected_sql = capture_sql { author.thinking_posts.delete_all }
 
-    author.thinking_posts.create!(:body => "test")
+    author.thinking_posts.create!(body: "test")
     author.reload
     author.thinking_posts.inspect
     loaded_sql = capture_sql { author.thinking_posts.delete_all }
@@ -263,11 +284,11 @@ class HasManyAssociationsTest < ActiveRecord::TestCase
 
   def test_delete_all_on_association_with_nil_dependency_is_the_same_as_not_loaded
     author = authors :david
-    author.posts.create!(:title => "test", :body => "body")
+    author.posts.create!(title: "test", body: "body")
     author.reload
     expected_sql = capture_sql { author.posts.delete_all }
 
-    author.posts.create!(:title => "test", :body => "body")
+    author.posts.create!(title: "test", body: "body")
     author.reload
     author.posts.to_a
     loaded_sql = capture_sql { author.posts.delete_all }
@@ -282,29 +303,29 @@ class HasManyAssociationsTest < ActiveRecord::TestCase
 
   def test_building_the_associated_object_with_explicit_sti_base_class
     firm = DependentFirm.new
-    company = firm.companies.build(:type => "Company")
+    company = firm.companies.build(type: "Company")
     assert_kind_of Company, company, "Expected #{company.class} to be a Company"
   end
 
   def test_building_the_associated_object_with_sti_subclass
     firm = DependentFirm.new
-    company = firm.companies.build(:type => "Client")
+    company = firm.companies.build(type: "Client")
     assert_kind_of Client, company, "Expected #{company.class} to be a Client"
   end
 
   def test_building_the_associated_object_with_an_invalid_type
     firm = DependentFirm.new
-    assert_raise(ActiveRecord::SubclassNotFound) { firm.companies.build(:type => "Invalid") }
+    assert_raise(ActiveRecord::SubclassNotFound) { firm.companies.build(type: "Invalid") }
   end
 
   def test_building_the_associated_object_with_an_unrelated_type
     firm = DependentFirm.new
-    assert_raise(ActiveRecord::SubclassNotFound) { firm.companies.build(:type => "Account") }
+    assert_raise(ActiveRecord::SubclassNotFound) { firm.companies.build(type: "Account") }
   end
 
   test "building the association with an array" do
     speedometer = Speedometer.new(speedometer_id: "a")
-    data = [{name: "first"}, {name: "second"}]
+    data = [{ name: "first" }, { name: "second" }]
     speedometer.minivans.build(data)
 
     assert_equal 2, speedometer.minivans.size
@@ -313,24 +334,24 @@ class HasManyAssociationsTest < ActiveRecord::TestCase
   end
 
   def test_association_keys_bypass_attribute_protection
-    car = Car.create(:name => 'honda')
+    car = Car.create(name: "honda")
 
     bulb = car.bulbs.new
     assert_equal car.id, bulb.car_id
 
-    bulb = car.bulbs.new :car_id => car.id + 1
+    bulb = car.bulbs.new car_id: car.id + 1
     assert_equal car.id, bulb.car_id
 
     bulb = car.bulbs.build
     assert_equal car.id, bulb.car_id
 
-    bulb = car.bulbs.build :car_id => car.id + 1
+    bulb = car.bulbs.build car_id: car.id + 1
     assert_equal car.id, bulb.car_id
 
     bulb = car.bulbs.create
     assert_equal car.id, bulb.car_id
 
-    bulb = car.bulbs.create :car_id => car.id + 1
+    bulb = car.bulbs.create car_id: car.id + 1
     assert_equal car.id, bulb.car_id
   end
 
@@ -340,19 +361,19 @@ class HasManyAssociationsTest < ActiveRecord::TestCase
     line_item = invoice.line_items.new
     assert_equal invoice.id, line_item.invoice_id
 
-    line_item = invoice.line_items.new :invoice_id => invoice.id + 1
+    line_item = invoice.line_items.new invoice_id: invoice.id + 1
     assert_equal invoice.id, line_item.invoice_id
 
     line_item = invoice.line_items.build
     assert_equal invoice.id, line_item.invoice_id
 
-    line_item = invoice.line_items.build :invoice_id => invoice.id + 1
+    line_item = invoice.line_items.build invoice_id: invoice.id + 1
     assert_equal invoice.id, line_item.invoice_id
 
     line_item = invoice.line_items.create
     assert_equal invoice.id, line_item.invoice_id
 
-    line_item = invoice.line_items.create :invoice_id => invoice.id + 1
+    line_item = invoice.line_items.create invoice_id: invoice.id + 1
     assert_equal invoice.id, line_item.invoice_id
   end
 
@@ -373,64 +394,98 @@ class HasManyAssociationsTest < ActiveRecord::TestCase
   end
 
   def test_no_sql_should_be_fired_if_association_already_loaded
-    Car.create(:name => 'honda')
+    Car.create(name: "honda")
     bulbs = Car.first.bulbs
     bulbs.to_a # to load all instances of bulbs
 
     assert_no_queries do
       bulbs.first()
-      bulbs.first({})
     end
 
     assert_no_queries do
       bulbs.second()
-      bulbs.second({})
     end
 
     assert_no_queries do
       bulbs.third()
-      bulbs.third({})
     end
 
     assert_no_queries do
       bulbs.fourth()
-      bulbs.fourth({})
     end
 
     assert_no_queries do
       bulbs.fifth()
-      bulbs.fifth({})
     end
 
     assert_no_queries do
       bulbs.forty_two()
-      bulbs.forty_two({})
     end
 
     assert_no_queries do
       bulbs.third_to_last()
-      bulbs.third_to_last({})
     end
 
     assert_no_queries do
       bulbs.second_to_last()
-      bulbs.second_to_last({})
     end
 
     assert_no_queries do
       bulbs.last()
-      bulbs.last({})
+    end
+  end
+
+  def test_finder_method_with_dirty_target
+    company = companies(:first_firm)
+    new_clients = []
+    assert_no_queries(ignore_none: false) do
+      new_clients << company.clients_of_firm.build(name: "Another Client")
+      new_clients << company.clients_of_firm.build(name: "Another Client II")
+      new_clients << company.clients_of_firm.build(name: "Another Client III")
+    end
+
+    assert_not company.clients_of_firm.loaded?
+    assert_queries(1) do
+      assert_same new_clients[0], company.clients_of_firm.third
+      assert_same new_clients[1], company.clients_of_firm.fourth
+      assert_same new_clients[2], company.clients_of_firm.fifth
+      assert_same new_clients[0], company.clients_of_firm.third_to_last
+      assert_same new_clients[1], company.clients_of_firm.second_to_last
+      assert_same new_clients[2], company.clients_of_firm.last
+    end
+  end
+
+  def test_finder_bang_method_with_dirty_target
+    company = companies(:first_firm)
+    new_clients = []
+    assert_no_queries(ignore_none: false) do
+      new_clients << company.clients_of_firm.build(name: "Another Client")
+      new_clients << company.clients_of_firm.build(name: "Another Client II")
+      new_clients << company.clients_of_firm.build(name: "Another Client III")
+    end
+
+    assert_not company.clients_of_firm.loaded?
+    assert_queries(1) do
+      assert_same new_clients[0], company.clients_of_firm.third!
+      assert_same new_clients[1], company.clients_of_firm.fourth!
+      assert_same new_clients[2], company.clients_of_firm.fifth!
+      assert_same new_clients[0], company.clients_of_firm.third_to_last!
+      assert_same new_clients[1], company.clients_of_firm.second_to_last!
+      assert_same new_clients[2], company.clients_of_firm.last!
     end
   end
 
   def test_create_resets_cached_counters
-    person = Person.create!(:first_name => 'tenderlove')
+    Reader.delete_all
+
+    person = Person.create!(first_name: "tenderlove")
+
     post   = Post.first
 
     assert_equal [], person.readers
     assert_nil person.readers.find_by_post_id(post.id)
 
-    person.readers.create(:post_id => post.id)
+    person.readers.create(post_id: post.id)
 
     assert_equal 1, person.readers.count
     assert_equal 1, person.readers.length
@@ -438,25 +493,40 @@ class HasManyAssociationsTest < ActiveRecord::TestCase
     assert_equal person, person.readers.first.person
   end
 
-  def force_signal37_to_load_all_clients_of_firm
-    companies(:first_firm).clients_of_firm.each {|f| }
+  def test_update_all_respects_association_scope
+    person = Person.new
+    person.first_name = "Naruto"
+    person.references << Reference.new
+    person.id = 10
+    person.references
+    person.save!
+    assert_equal 1, person.references.update_all(favourite: true)
+  end
+
+  def test_exists_respects_association_scope
+    person = Person.new
+    person.first_name = "Sasuke"
+    person.references << Reference.new
+    person.id = 10
+    person.references
+    person.save!
+    assert_predicate person.references, :exists?
   end
 
-  # sometimes tests on Oracle fail if ORDER BY is not provided therefore add always :order with :first
   def test_counting_with_counter_sql
-    assert_equal 3, Firm.all.merge!(:order => "id").first.clients.count
+    assert_equal 3, Firm.first.clients.count
   end
 
   def test_counting
-    assert_equal 3, Firm.all.merge!(:order => "id").first.plain_clients.count
+    assert_equal 3, Firm.first.plain_clients.count
   end
 
   def test_counting_with_single_hash
-    assert_equal 1, Firm.all.merge!(:order => "id").first.plain_clients.where(:name => "Microsoft").count
+    assert_equal 1, Firm.first.plain_clients.where(name: "Microsoft").count
   end
 
   def test_counting_with_column_name_and_hash
-    assert_equal 3, Firm.all.merge!(:order => "id").first.plain_clients.count(:name)
+    assert_equal 3, Firm.first.plain_clients.count(:name)
   end
 
   def test_counting_with_association_limit
@@ -466,11 +536,11 @@ class HasManyAssociationsTest < ActiveRecord::TestCase
   end
 
   def test_finding
-    assert_equal 3, Firm.all.merge!(:order => "id").first.clients.length
+    assert_equal 3, Firm.first.clients.length
   end
 
   def test_finding_array_compatibility
-    assert_equal 3, Firm.order(:id).find{|f| f.id > 0}.clients.length
+    assert_equal 3, Firm.order(:id).find { |f| f.id > 0 }.clients.length
   end
 
   def test_find_many_with_merged_options
@@ -480,13 +550,13 @@ class HasManyAssociationsTest < ActiveRecord::TestCase
   end
 
   def test_find_should_append_to_association_order
-    ordered_clients =  companies(:first_firm).clients_sorted_desc.order('companies.id')
-    assert_equal ['id DESC', 'companies.id'], ordered_clients.order_values
+    ordered_clients = companies(:first_firm).clients_sorted_desc.order("companies.id")
+    assert_equal ["id DESC", "companies.id"], ordered_clients.order_values
   end
 
   def test_dynamic_find_should_respect_association_order
     assert_equal companies(:another_first_firm_client), companies(:first_firm).clients_sorted_desc.where("type = 'Client'").first
-    assert_equal companies(:another_first_firm_client), companies(:first_firm).clients_sorted_desc.find_by_type('Client')
+    assert_equal companies(:another_first_firm_client), companies(:first_firm).clients_sorted_desc.find_by_type("Client")
   end
 
   def test_taking
@@ -506,16 +576,28 @@ class HasManyAssociationsTest < ActiveRecord::TestCase
   end
 
   def test_taking_with_a_number
+    klass = Class.new(Author) do
+      has_many :posts, -> { order(:id) }
+
+      def self.name
+        "Author"
+      end
+    end
+
     # taking from unloaded Relation
-    bob = Author.find(authors(:bob).id)
+    bob = klass.find(authors(:bob).id)
+    new_post = bob.posts.build
+    assert_not bob.posts.loaded?
     assert_equal [posts(:misc_by_bob)], bob.posts.take(1)
-    bob = Author.find(authors(:bob).id)
     assert_equal [posts(:misc_by_bob), posts(:other_by_bob)], bob.posts.take(2)
+    assert_equal [posts(:misc_by_bob), posts(:other_by_bob), new_post], bob.posts.take(3)
 
     # taking from loaded Relation
-    bob.posts.to_a
-    assert_equal [posts(:misc_by_bob)], authors(:bob).posts.take(1)
-    assert_equal [posts(:misc_by_bob), posts(:other_by_bob)], authors(:bob).posts.take(2)
+    bob.posts.load
+    assert bob.posts.loaded?
+    assert_equal [posts(:misc_by_bob)], bob.posts.take(1)
+    assert_equal [posts(:misc_by_bob), posts(:other_by_bob)], bob.posts.take(2)
+    assert_equal [posts(:misc_by_bob), posts(:other_by_bob), new_post], bob.posts.take(3)
   end
 
   def test_taking_with_inverse_of
@@ -534,46 +616,41 @@ class HasManyAssociationsTest < ActiveRecord::TestCase
   end
 
   def test_finding_default_orders
-    assert_equal "Summit", Firm.all.merge!(:order => "id").first.clients.first.name
+    assert_equal "Summit", Firm.first.clients.first.name
   end
 
   def test_finding_with_different_class_name_and_order
-    assert_equal "Apex", Firm.all.merge!(:order => "id").first.clients_sorted_desc.first.name
+    assert_equal "Apex", Firm.first.clients_sorted_desc.first.name
   end
 
   def test_finding_with_foreign_key
-    assert_equal "Microsoft", Firm.all.merge!(:order => "id").first.clients_of_firm.first.name
+    assert_equal "Microsoft", Firm.first.clients_of_firm.first.name
   end
 
   def test_finding_with_condition
-    assert_equal "Microsoft", Firm.all.merge!(:order => "id").first.clients_like_ms.first.name
+    assert_equal "Microsoft", Firm.first.clients_like_ms.first.name
   end
 
   def test_finding_with_condition_hash
-    assert_equal "Microsoft", Firm.all.merge!(:order => "id").first.clients_like_ms_with_hash_conditions.first.name
+    assert_equal "Microsoft", Firm.first.clients_like_ms_with_hash_conditions.first.name
   end
 
   def test_finding_using_primary_key
-    assert_equal "Summit", Firm.all.merge!(:order => "id").first.clients_using_primary_key.first.name
+    assert_equal "Summit", Firm.first.clients_using_primary_key.first.name
   end
 
   def test_update_all_on_association_accessed_before_save
-    firm = Firm.new(name: 'Firm')
-    clients_proxy_id = firm.clients.object_id
+    firm = Firm.new(name: "Firm")
     firm.clients << Client.first
     firm.save!
-    assert_equal firm.clients.count, firm.clients.update_all(description: 'Great!')
-    assert_not_equal clients_proxy_id, firm.clients.object_id
+    assert_equal firm.clients.count, firm.clients.update_all(description: "Great!")
   end
 
   def test_update_all_on_association_accessed_before_save_with_explicit_foreign_key
-    # We can use the same cached proxy object because the id is available for the scope
-    firm = Firm.new(name: 'Firm', id: 100)
-    clients_proxy_id = firm.clients.object_id
+    firm = Firm.new(name: "Firm", id: 100)
     firm.clients << Client.first
     firm.save!
-    assert_equal firm.clients.count, firm.clients.update_all(description: 'Great!')
-    assert_equal clients_proxy_id, firm.clients.object_id
+    assert_equal firm.clients.count, firm.clients.update_all(description: "Great!")
   end
 
   def test_belongs_to_sanity
@@ -582,7 +659,7 @@ class HasManyAssociationsTest < ActiveRecord::TestCase
   end
 
   def test_find_ids
-    firm = Firm.all.merge!(:order => "id").first
+    firm = Firm.first
 
     assert_raise(ActiveRecord::RecordNotFound) { firm.clients.find }
 
@@ -601,9 +678,23 @@ class HasManyAssociationsTest < ActiveRecord::TestCase
     assert_raise(ActiveRecord::RecordNotFound) { firm.clients.find(2, 99) }
   end
 
+  def test_find_one_message_on_primary_key
+    firm = Firm.first
+
+    e = assert_raises(ActiveRecord::RecordNotFound) do
+      firm.clients.find(0)
+    end
+    assert_equal 0, e.id
+    assert_equal "id", e.primary_key
+    assert_equal "Client", e.model
+    assert_match (/\ACouldn't find Client with 'id'=0/), e.message
+  end
+
   def test_find_ids_and_inverse_of
     force_signal37_to_load_all_clients_of_firm
 
+    assert_predicate companies(:first_firm).clients_of_firm, :loaded?
+
     firm = companies(:first_firm)
     client = firm.clients_of_firm.find(3)
     assert_kind_of Client, client
@@ -614,7 +705,7 @@ class HasManyAssociationsTest < ActiveRecord::TestCase
   end
 
   def test_find_all
-    firm = Firm.all.merge!(:order => "id").first
+    firm = Firm.first
     assert_equal 3, firm.clients.where("#{QUOTED_TYPE} = 'Client'").to_a.length
     assert_equal 1, firm.clients.where("name = 'Summit'").to_a.length
   end
@@ -625,7 +716,7 @@ class HasManyAssociationsTest < ActiveRecord::TestCase
     assert ! firm.clients.loaded?
 
     assert_queries(4) do
-      firm.clients.find_each(:batch_size => 1) {|c| assert_equal firm.id, c.firm_id }
+      firm.clients.find_each(batch_size: 1) { |c| assert_equal firm.id, c.firm_id }
     end
 
     assert ! firm.clients.loaded?
@@ -635,7 +726,7 @@ class HasManyAssociationsTest < ActiveRecord::TestCase
     firm = companies(:first_firm)
 
     assert_queries(2) do
-      firm.clients.where(name: 'Microsoft').find_each(batch_size: 1) do |c|
+      firm.clients.where(name: "Microsoft").find_each(batch_size: 1) do |c|
         assert_equal firm.id, c.firm_id
         assert_equal "Microsoft", c.name
       end
@@ -650,8 +741,8 @@ class HasManyAssociationsTest < ActiveRecord::TestCase
     assert ! firm.clients.loaded?
 
     assert_queries(2) do
-      firm.clients.find_in_batches(:batch_size => 2) do |clients|
-        clients.each {|c| assert_equal firm.id, c.firm_id }
+      firm.clients.find_in_batches(batch_size: 2) do |clients|
+        clients.each { |c| assert_equal firm.id, c.firm_id }
       end
     end
 
@@ -659,30 +750,64 @@ class HasManyAssociationsTest < ActiveRecord::TestCase
   end
 
   def test_find_all_sanitized
-    # sometimes tests on Oracle fail if ORDER BY is not provided therefore add always :order with :first
-    firm = Firm.all.merge!(:order => "id").first
+    firm = Firm.first
     summit = firm.clients.where("name = 'Summit'").to_a
     assert_equal summit, firm.clients.where("name = ?", "Summit").to_a
-    assert_equal summit, firm.clients.where("name = :name", { :name => "Summit" }).to_a
+    assert_equal summit, firm.clients.where("name = :name", name: "Summit").to_a
   end
 
   def test_find_first
-    firm = Firm.all.merge!(:order => "id").first
+    firm = Firm.first
     client2 = Client.find(2)
     assert_equal firm.clients.first, firm.clients.order("id").first
     assert_equal client2, firm.clients.where("#{QUOTED_TYPE} = 'Client'").order("id").first
   end
 
   def test_find_first_sanitized
-    firm = Firm.all.merge!(:order => "id").first
+    firm = Firm.first
     client2 = Client.find(2)
-    assert_equal client2, firm.clients.merge!(:where => ["#{QUOTED_TYPE} = ?", 'Client'], :order => "id").first
-    assert_equal client2, firm.clients.merge!(:where => ["#{QUOTED_TYPE} = :type", { :type => 'Client' }], :order => "id").first
+    assert_equal client2, firm.clients.where("#{QUOTED_TYPE} = ?", "Client").first
+    assert_equal client2, firm.clients.where("#{QUOTED_TYPE} = :type", type: "Client").first
+  end
+
+  def test_find_first_after_reset_scope
+    firm = Firm.first
+    collection = firm.clients
+
+    original_object = collection.first
+    assert_same original_object, collection.first, "Expected second call to #first to cache the same object"
+
+    # It should return a different object, since the association has been reloaded
+    assert_not_same original_object, firm.clients.first, "Expected #first to return a new object"
+  end
+
+  def test_find_first_after_reset
+    firm = Firm.first
+    collection = firm.clients
+
+    original_object = collection.first
+    assert_same original_object, collection.first, "Expected second call to #first to cache the same object"
+    collection.reset
+
+    # It should return a different object, since the association has been reloaded
+    assert_not_same original_object, collection.first, "Expected #first after #reset to return a new object"
+  end
+
+  def test_find_first_after_reload
+    firm = Firm.first
+    collection = firm.clients
+
+    original_object = collection.first
+    assert_same original_object, collection.first, "Expected second call to #first to cache the same object"
+    collection.reload
+
+    # It should return a different object, since the association has been reloaded
+    assert_not_same original_object, collection.first, "Expected #first after #reload to return a new object"
   end
 
   def test_find_all_with_include_and_conditions
     assert_nothing_raised do
-      Developer.all.merge!(:joins => :audit_logs, :where => {'audit_logs.message' => nil, :name => 'Smith'}).to_a
+      Developer.all.merge!(joins: :audit_logs, where: { "audit_logs.message" => nil, :name => "Smith" }).to_a
     end
   end
 
@@ -692,8 +817,8 @@ class HasManyAssociationsTest < ActiveRecord::TestCase
   end
 
   def test_find_grouped
-    all_clients_of_firm1 = Client.all.merge!(:where => "firm_id = 1").to_a
-    grouped_clients_of_firm1 = Client.all.merge!(:where => "firm_id = 1", :group => "firm_id", :select => 'firm_id, count(id) as clients_count').to_a
+    all_clients_of_firm1 = Client.all.merge!(where: "firm_id = 1").to_a
+    grouped_clients_of_firm1 = Client.all.merge!(where: "firm_id = 1", group: "firm_id", select: "firm_id, count(id) as clients_count").to_a
     assert_equal 3, all_clients_of_firm1.size
     assert_equal 1, grouped_clients_of_firm1.size
   end
@@ -706,7 +831,7 @@ class HasManyAssociationsTest < ActiveRecord::TestCase
   end
 
   def test_find_scoped_grouped_having
-    assert_equal 1, authors(:david).popular_grouped_posts.length
+    assert_equal 2, authors(:david).popular_grouped_posts.length
     assert_equal 0, authors(:mary).popular_grouped_posts.length
   end
 
@@ -715,19 +840,28 @@ class HasManyAssociationsTest < ActiveRecord::TestCase
   end
 
   def test_select_query_method
-    assert_equal ['id', 'body'], posts(:welcome).comments.select(:id, :body).first.attributes.keys
+    assert_equal ["id", "body"], posts(:welcome).comments.select(:id, :body).first.attributes.keys
   end
 
   def test_select_with_block
     assert_equal [1], posts(:welcome).comments.select { |c| c.id == 1 }.map(&:id)
   end
 
+  def test_select_with_block_and_dirty_target
+    assert_equal 2, posts(:welcome).comments.select { true }.size
+    posts(:welcome).comments.build
+    assert_equal 3, posts(:welcome).comments.select { true }.size
+  end
+
   def test_select_without_foreign_key
     assert_equal companies(:first_firm).accounts.first.credit_limit, companies(:first_firm).accounts.select(:credit_limit).first.credit_limit
   end
 
   def test_adding
     force_signal37_to_load_all_clients_of_firm
+
+    assert_predicate companies(:first_firm).clients_of_firm, :loaded?
+
     natural = Client.new("name" => "Natural Company")
     companies(:first_firm).clients_of_firm << natural
     assert_equal 3, companies(:first_firm).clients_of_firm.size # checking via the collection
@@ -738,7 +872,7 @@ class HasManyAssociationsTest < ActiveRecord::TestCase
   def test_adding_using_create
     first_firm = companies(:first_firm)
     assert_equal 3, first_firm.plain_clients.size
-    first_firm.plain_clients.create(:name => "Natural Company")
+    first_firm.plain_clients.create(name: "Natural Company")
     assert_equal 4, first_firm.plain_clients.length
     assert_equal 4, first_firm.plain_clients.size
   end
@@ -746,7 +880,7 @@ class HasManyAssociationsTest < ActiveRecord::TestCase
   def test_create_with_bang_on_has_many_when_parent_is_new_raises
     error = assert_raise(ActiveRecord::RecordNotSaved) do
       firm = Firm.new
-      firm.plain_clients.create! :name=>"Whoever"
+      firm.plain_clients.create! name: "Whoever"
     end
 
     assert_equal "You cannot call create unless the parent is saved", error.message
@@ -755,7 +889,7 @@ class HasManyAssociationsTest < ActiveRecord::TestCase
   def test_regular_create_on_has_many_when_parent_is_new_raises
     error = assert_raise(ActiveRecord::RecordNotSaved) do
       firm = Firm.new
-      firm.plain_clients.create :name=>"Whoever"
+      firm.plain_clients.create name: "Whoever"
     end
 
     assert_equal "You cannot call create unless the parent is saved", error.message
@@ -763,7 +897,7 @@ class HasManyAssociationsTest < ActiveRecord::TestCase
 
   def test_create_with_bang_on_has_many_raises_when_record_not_saved
     assert_raise(ActiveRecord::RecordInvalid) do
-      firm = Firm.all.merge!(:order => "id").first
+      firm = Firm.first
       firm.plain_clients.create!
     end
   end
@@ -784,21 +918,24 @@ class HasManyAssociationsTest < ActiveRecord::TestCase
 
   def test_adding_a_collection
     force_signal37_to_load_all_clients_of_firm
+
+    assert_predicate companies(:first_firm).clients_of_firm, :loaded?
+
     companies(:first_firm).clients_of_firm.concat([Client.new("name" => "Natural Company"), Client.new("name" => "Apple")])
     assert_equal 4, companies(:first_firm).clients_of_firm.size
     assert_equal 4, companies(:first_firm).clients_of_firm.reload.size
   end
 
   def test_transactions_when_adding_to_persisted
-    good = Client.new(:name => "Good")
-    bad  = Client.new(:name => "Bad", :raise_on_save => true)
+    good = Client.new(name: "Good")
+    bad  = Client.new(name: "Bad", raise_on_save: true)
 
     begin
       companies(:first_firm).clients_of_firm.concat(good, bad)
     rescue Client::RaisedOnSave
     end
 
-    assert !companies(:first_firm).clients_of_firm.reload.include?(good)
+    assert_not_includes companies(:first_firm).clients_of_firm.reload, good
   end
 
   def test_transactions_when_adding_to_new_record
@@ -840,6 +977,7 @@ class HasManyAssociationsTest < ActiveRecord::TestCase
     company.clients_of_firm.build("name" => "Another Client")
     company.clients_of_firm.build("name" => "Yet Another Client")
     assert_equal 4, company.clients_of_firm.size
+    assert_equal 4, company.clients_of_firm.uniq.size
   end
 
   def test_collection_not_empty_after_building
@@ -863,7 +1001,7 @@ class HasManyAssociationsTest < ActiveRecord::TestCase
 
   def test_build_many
     company = companies(:first_firm)
-    new_clients = assert_no_queries(ignore_none: false) { company.clients_of_firm.build([{"name" => "Another Client"}, {"name" => "Another Client II"}]) }
+    new_clients = assert_no_queries(ignore_none: false) { company.clients_of_firm.build([{ "name" => "Another Client" }, { "name" => "Another Client II" }]) }
     assert_equal 2, new_clients.size
   end
 
@@ -880,7 +1018,7 @@ class HasManyAssociationsTest < ActiveRecord::TestCase
     assert_equal 1, first_topic.replies.length
 
     assert_no_queries do
-      first_topic.replies.build(:title => "Not saved", :content => "Superstars")
+      first_topic.replies.build(title: "Not saved", content: "Superstars")
       assert_equal 2, first_topic.replies.size
     end
 
@@ -889,7 +1027,7 @@ class HasManyAssociationsTest < ActiveRecord::TestCase
 
   def test_build_via_block
     company = companies(:first_firm)
-    new_client = assert_no_queries(ignore_none: false) { company.clients_of_firm.build {|client| client.name = "Another Client" } }
+    new_client = assert_no_queries(ignore_none: false) { company.clients_of_firm.build { |client| client.name = "Another Client" } }
     assert !company.clients_of_firm.loaded?
 
     assert_equal "Another Client", new_client.name
@@ -900,7 +1038,7 @@ class HasManyAssociationsTest < ActiveRecord::TestCase
   def test_build_many_via_block
     company = companies(:first_firm)
     new_clients = assert_no_queries(ignore_none: false) do
-      company.clients_of_firm.build([{"name" => "Another Client"}, {"name" => "Another Client II"}]) do |client|
+      company.clients_of_firm.build([{ "name" => "Another Client" }, { "name" => "Another Client II" }]) do |client|
         client.name = "changed"
       end
     end
@@ -911,7 +1049,7 @@ class HasManyAssociationsTest < ActiveRecord::TestCase
   end
 
   def test_create_without_loading_association
-    first_firm  = companies(:first_firm)
+    first_firm = companies(:first_firm)
     Firm.column_names
     Client.column_names
 
@@ -919,7 +1057,7 @@ class HasManyAssociationsTest < ActiveRecord::TestCase
     first_firm.clients_of_firm.reset
 
     assert_queries(1) do
-      first_firm.clients_of_firm.create(:name => "Superstars")
+      first_firm.clients_of_firm.create(name: "Superstars")
     end
 
     assert_equal 3, first_firm.clients_of_firm.size
@@ -927,6 +1065,9 @@ class HasManyAssociationsTest < ActiveRecord::TestCase
 
   def test_create
     force_signal37_to_load_all_clients_of_firm
+
+    assert_predicate companies(:first_firm).clients_of_firm, :loaded?
+
     new_client = companies(:first_firm).clients_of_firm.create("name" => "Another Client")
     assert new_client.persisted?
     assert_equal new_client, companies(:first_firm).clients_of_firm.last
@@ -934,7 +1075,7 @@ class HasManyAssociationsTest < ActiveRecord::TestCase
   end
 
   def test_create_many
-    companies(:first_firm).clients_of_firm.create([{"name" => "Another Client"}, {"name" => "Another Client II"}])
+    companies(:first_firm).clients_of_firm.create([{ "name" => "Another Client" }, { "name" => "Another Client II" }])
     assert_equal 4, companies(:first_firm).clients_of_firm.reload.size
   end
 
@@ -946,6 +1087,9 @@ class HasManyAssociationsTest < ActiveRecord::TestCase
 
   def test_deleting
     force_signal37_to_load_all_clients_of_firm
+
+    assert_predicate companies(:first_firm).clients_of_firm, :loaded?
+
     companies(:first_firm).clients_of_firm.delete(companies(:first_firm).clients_of_firm.first)
     assert_equal 1, companies(:first_firm).clients_of_firm.size
     assert_equal 1, companies(:first_firm).clients_of_firm.reload.size
@@ -962,7 +1106,7 @@ class HasManyAssociationsTest < ActiveRecord::TestCase
   def test_has_many_without_counter_cache_option
     # Ship has a conventionally named `treasures_count` column, but the counter_cache
     # option is not given on the association.
-    ship = Ship.create(name: 'Countless', treasures_count: 10)
+    ship = Ship.create(name: "Countless", treasures_count: 10)
 
     assert_not Ship.reflect_on_association(:treasures).has_cached_counter?
 
@@ -970,7 +1114,7 @@ class HasManyAssociationsTest < ActiveRecord::TestCase
     assert_equal ship.treasures.size, 0
 
     assert_no_difference lambda { ship.reload.treasures_count }, "treasures_count should not be changed" do
-      ship.treasures.create(name: 'Gold')
+      ship.treasures.create(name: "Gold")
     end
 
     assert_no_difference lambda { ship.reload.treasures_count }, "treasures_count should not be changed" do
@@ -1073,10 +1217,10 @@ class HasManyAssociationsTest < ActiveRecord::TestCase
     assert_equal original_count, topic.replies_count
 
     first_reply = topic.replies.first
-    first_reply.update_attributes(:parent_id => nil)
+    first_reply.update_attributes(parent_id: nil)
     assert_equal original_count - 1, topic.reload.replies_count
 
-    first_reply.update_attributes(:parent_id => topic.id)
+    first_reply.update_attributes(parent_id: topic.id)
     assert_equal original_count, topic.reload.replies_count
   end
 
@@ -1089,17 +1233,20 @@ class HasManyAssociationsTest < ActiveRecord::TestCase
     reply1 = topic1.replies.first
     reply2 = topic2.replies.first
 
-    reply1.update_attributes(:parent_id => topic2.id)
+    reply1.update_attributes(parent_id: topic2.id)
     assert_equal original_count1 - 1, topic1.reload.replies_count
     assert_equal original_count2 + 1, topic2.reload.replies_count
 
-    reply2.update_attributes(:parent_id => topic1.id)
+    reply2.update_attributes(parent_id: topic1.id)
     assert_equal original_count1, topic1.reload.replies_count
     assert_equal original_count2, topic2.reload.replies_count
   end
 
   def test_deleting_a_collection
     force_signal37_to_load_all_clients_of_firm
+
+    assert_predicate companies(:first_firm).clients_of_firm, :loaded?
+
     companies(:first_firm).clients_of_firm.create("name" => "Another Client")
     assert_equal 3, companies(:first_firm).clients_of_firm.size
     companies(:first_firm).clients_of_firm.delete([companies(:first_firm).clients_of_firm[0], companies(:first_firm).clients_of_firm[1], companies(:first_firm).clients_of_firm[2]])
@@ -1109,6 +1256,9 @@ class HasManyAssociationsTest < ActiveRecord::TestCase
 
   def test_delete_all
     force_signal37_to_load_all_clients_of_firm
+
+    assert_predicate companies(:first_firm).clients_of_firm, :loaded?
+
     companies(:first_firm).dependent_clients_of_firm.create("name" => "Another Client")
     clients = companies(:first_firm).dependent_clients_of_firm.to_a
     assert_equal 3, clients.count
@@ -1120,6 +1270,9 @@ class HasManyAssociationsTest < ActiveRecord::TestCase
 
   def test_delete_all_with_not_yet_loaded_association_collection
     force_signal37_to_load_all_clients_of_firm
+
+    assert_predicate companies(:first_firm).clients_of_firm, :loaded?
+
     companies(:first_firm).clients_of_firm.create("name" => "Another Client")
     assert_equal 3, companies(:first_firm).clients_of_firm.size
     companies(:first_firm).clients_of_firm.reset
@@ -1129,8 +1282,8 @@ class HasManyAssociationsTest < ActiveRecord::TestCase
   end
 
   def test_transaction_when_deleting_persisted
-    good = Client.new(:name => "Good")
-    bad  = Client.new(:name => "Bad", :raise_on_destroy => true)
+    good = Client.new(name: "Good")
+    bad  = Client.new(name: "Bad", raise_on_destroy: true)
 
     companies(:first_firm).clients_of_firm = [good, bad]
 
@@ -1171,7 +1324,7 @@ class HasManyAssociationsTest < ActiveRecord::TestCase
   def test_clearing_updates_counter_cache
     topic = Topic.first
 
-    assert_difference 'topic.reload.replies_count', -1 do
+    assert_difference "topic.reload.replies_count", -1 do
       topic.replies.clear
     end
   end
@@ -1180,7 +1333,7 @@ class HasManyAssociationsTest < ActiveRecord::TestCase
     car = Car.first
     car.engines.create!
 
-    assert_difference 'car.reload.engines_count', -1 do
+    assert_difference "car.reload.engines_count", -1 do
       car.engines.clear
     end
   end
@@ -1238,8 +1391,8 @@ class HasManyAssociationsTest < ActiveRecord::TestCase
 
   def test_dependent_association_respects_optional_conditions_on_delete
     firm = companies(:odegy)
-    Client.create(:client_of => firm.id, :name => "BigShot Inc.")
-    Client.create(:client_of => firm.id, :name => "SmallTime Inc.")
+    Client.create(client_of: firm.id, name: "BigShot Inc.")
+    Client.create(client_of: firm.id, name: "SmallTime Inc.")
     # only one of two clients is included in the association due to the :conditions key
     assert_equal 2, Client.where(client_of: firm.id).size
     assert_equal 1, firm.dependent_conditional_clients_of_firm.size
@@ -1250,8 +1403,8 @@ class HasManyAssociationsTest < ActiveRecord::TestCase
 
   def test_dependent_association_respects_optional_sanitized_conditions_on_delete
     firm = companies(:odegy)
-    Client.create(:client_of => firm.id, :name => "BigShot Inc.")
-    Client.create(:client_of => firm.id, :name => "SmallTime Inc.")
+    Client.create(client_of: firm.id, name: "BigShot Inc.")
+    Client.create(client_of: firm.id, name: "SmallTime Inc.")
     # only one of two clients is included in the association due to the :conditions key
     assert_equal 2, Client.where(client_of: firm.id).size
     assert_equal 1, firm.dependent_sanitized_conditional_clients_of_firm.size
@@ -1262,11 +1415,11 @@ class HasManyAssociationsTest < ActiveRecord::TestCase
 
   def test_dependent_association_respects_optional_hash_conditions_on_delete
     firm = companies(:odegy)
-    Client.create(:client_of => firm.id, :name => "BigShot Inc.")
-    Client.create(:client_of => firm.id, :name => "SmallTime Inc.")
+    Client.create(client_of: firm.id, name: "BigShot Inc.")
+    Client.create(client_of: firm.id, name: "SmallTime Inc.")
     # only one of two clients is included in the association due to the :conditions key
     assert_equal 2, Client.where(client_of: firm.id).size
-    assert_equal 1, firm.dependent_sanitized_conditional_clients_of_firm.size
+    assert_equal 1, firm.dependent_hash_conditional_clients_of_firm.size
     firm.destroy
     # only the correctly associated client should have been deleted
     assert_equal 1, Client.where(client_of: firm.id).size
@@ -1289,12 +1442,12 @@ class HasManyAssociationsTest < ActiveRecord::TestCase
     ms_client = companies(:first_firm).clients_like_ms_with_hash_conditions.build
 
     assert        ms_client.save
-    assert_equal  'Microsoft', ms_client.name
+    assert_equal  "Microsoft", ms_client.name
 
     another_ms_client = companies(:first_firm).clients_like_ms_with_hash_conditions.create
 
     assert        another_ms_client.persisted?
-    assert_equal  'Microsoft', another_ms_client.name
+    assert_equal  "Microsoft", another_ms_client.name
   end
 
   def test_clearing_without_initial_access
@@ -1308,7 +1461,10 @@ class HasManyAssociationsTest < ActiveRecord::TestCase
 
   def test_deleting_a_item_which_is_not_in_the_collection
     force_signal37_to_load_all_clients_of_firm
-    summit = Client.find_by_name('Summit')
+
+    assert_predicate companies(:first_firm).clients_of_firm, :loaded?
+
+    summit = Client.find_by_name("Summit")
     companies(:first_firm).clients_of_firm.delete(summit)
     assert_equal 2, companies(:first_firm).clients_of_firm.size
     assert_equal 2, companies(:first_firm).clients_of_firm.reload.size
@@ -1318,7 +1474,7 @@ class HasManyAssociationsTest < ActiveRecord::TestCase
   def test_deleting_by_integer_id
     david = Developer.find(1)
 
-    assert_difference 'david.projects.count', -1 do
+    assert_difference "david.projects.count", -1 do
       assert_equal 1, david.projects.delete(1).size
     end
 
@@ -1328,8 +1484,8 @@ class HasManyAssociationsTest < ActiveRecord::TestCase
   def test_deleting_by_string_id
     david = Developer.find(1)
 
-    assert_difference 'david.projects.count', -1 do
-      assert_equal 1, david.projects.delete('1').size
+    assert_difference "david.projects.count", -1 do
+      assert_equal 1, david.projects.delete("1").size
     end
 
     assert_equal 1, david.projects.size
@@ -1344,6 +1500,8 @@ class HasManyAssociationsTest < ActiveRecord::TestCase
   def test_destroying
     force_signal37_to_load_all_clients_of_firm
 
+    assert_predicate companies(:first_firm).clients_of_firm, :loaded?
+
     assert_difference "Client.count", -1 do
       companies(:first_firm).clients_of_firm.destroy(companies(:first_firm).clients_of_firm.first)
     end
@@ -1355,6 +1513,8 @@ class HasManyAssociationsTest < ActiveRecord::TestCase
   def test_destroying_by_integer_id
     force_signal37_to_load_all_clients_of_firm
 
+    assert_predicate companies(:first_firm).clients_of_firm, :loaded?
+
     assert_difference "Client.count", -1 do
       companies(:first_firm).clients_of_firm.destroy(companies(:first_firm).clients_of_firm.first.id)
     end
@@ -1366,6 +1526,8 @@ class HasManyAssociationsTest < ActiveRecord::TestCase
   def test_destroying_by_string_id
     force_signal37_to_load_all_clients_of_firm
 
+    assert_predicate companies(:first_firm).clients_of_firm, :loaded?
+
     assert_difference "Client.count", -1 do
       companies(:first_firm).clients_of_firm.destroy(companies(:first_firm).clients_of_firm.first.id.to_s)
     end
@@ -1376,6 +1538,9 @@ class HasManyAssociationsTest < ActiveRecord::TestCase
 
   def test_destroying_a_collection
     force_signal37_to_load_all_clients_of_firm
+
+    assert_predicate companies(:first_firm).clients_of_firm, :loaded?
+
     companies(:first_firm).clients_of_firm.create("name" => "Another Client")
     assert_equal 3, companies(:first_firm).clients_of_firm.size
 
@@ -1389,6 +1554,9 @@ class HasManyAssociationsTest < ActiveRecord::TestCase
 
   def test_destroy_all
     force_signal37_to_load_all_clients_of_firm
+
+    assert_predicate companies(:first_firm).clients_of_firm, :loaded?
+
     clients = companies(:first_firm).clients_of_firm.to_a
     assert !clients.empty?, "37signals has clients after load"
     destroyed = companies(:first_firm).clients_of_firm.destroy_all
@@ -1402,17 +1570,16 @@ class HasManyAssociationsTest < ActiveRecord::TestCase
     firm = companies(:first_firm)
     assert_equal 3, firm.clients.size
     firm.destroy
-    assert Client.all.merge!(:where => "firm_id=#{firm.id}").to_a.empty?
+    assert Client.all.merge!(where: "firm_id=#{firm.id}").to_a.empty?
   end
 
   def test_dependence_for_associations_with_hash_condition
     david = authors(:david)
-    assert_difference('Post.count', -1) { assert david.destroy }
+    assert_difference("Post.count", -1) { assert david.destroy }
   end
 
   def test_destroy_dependent_when_deleted_from_association
-    # sometimes tests on Oracle fail if ORDER BY is not provided therefore add always :order with :first
-    firm = Firm.all.merge!(:order => "id").first
+    firm = Firm.first
     assert_equal 3, firm.clients.size
 
     client = firm.clients.first
@@ -1439,7 +1606,7 @@ class HasManyAssociationsTest < ActiveRecord::TestCase
 
     firm.destroy rescue "do nothing"
 
-    assert_equal 3, Client.all.merge!(:where => "firm_id=#{firm.id}").to_a.size
+    assert_equal 3, Client.all.merge!(where: "firm_id=#{firm.id}").to_a.size
   end
 
   def test_dependence_on_account
@@ -1463,38 +1630,18 @@ class HasManyAssociationsTest < ActiveRecord::TestCase
   end
 
   def test_restrict_with_exception
-    firm = RestrictedWithExceptionFirm.create!(:name => 'restrict')
-    firm.companies.create(:name => 'child')
+    firm = RestrictedWithExceptionFirm.create!(name: "restrict")
+    firm.companies.create(name: "child")
 
     assert !firm.companies.empty?
     assert_raise(ActiveRecord::DeleteRestrictionError) { firm.destroy }
-    assert RestrictedWithExceptionFirm.exists?(:name => 'restrict')
-    assert firm.companies.exists?(:name => 'child')
-  end
-
-  def test_restrict_with_error_is_deprecated_using_key_many
-    I18n.backend = I18n::Backend::Simple.new
-    I18n.backend.store_translations :en, activerecord: { errors: { messages: { restrict_dependent_destroy: { many: 'message for deprecated key' } } } }
-
-    firm = RestrictedWithErrorFirm.create!(name: 'restrict')
-    firm.companies.create(name: 'child')
-
-    assert !firm.companies.empty?
-
-    assert_deprecated { firm.destroy }
-
-    assert !firm.errors.empty?
-
-    assert_equal 'message for deprecated key', firm.errors[:base].first
-    assert RestrictedWithErrorFirm.exists?(name: 'restrict')
-    assert firm.companies.exists?(name: 'child')
-  ensure
-    I18n.backend.reload!
+    assert RestrictedWithExceptionFirm.exists?(name: "restrict")
+    assert firm.companies.exists?(name: "child")
   end
 
   def test_restrict_with_error
-    firm = RestrictedWithErrorFirm.create!(:name => 'restrict')
-    firm.companies.create(:name => 'child')
+    firm = RestrictedWithErrorFirm.create!(name: "restrict")
+    firm.companies.create(name: "child")
 
     assert !firm.companies.empty?
 
@@ -1503,15 +1650,15 @@ class HasManyAssociationsTest < ActiveRecord::TestCase
     assert !firm.errors.empty?
 
     assert_equal "Cannot delete record because dependent companies exist", firm.errors[:base].first
-    assert RestrictedWithErrorFirm.exists?(:name => 'restrict')
-    assert firm.companies.exists?(:name => 'child')
+    assert RestrictedWithErrorFirm.exists?(name: "restrict")
+    assert firm.companies.exists?(name: "child")
   end
 
   def test_restrict_with_error_with_locale
     I18n.backend = I18n::Backend::Simple.new
-    I18n.backend.store_translations 'en', activerecord: {attributes: {restricted_with_error_firm: {companies: 'client companies'}}}
-    firm = RestrictedWithErrorFirm.create!(name: 'restrict')
-    firm.companies.create(name: 'child')
+    I18n.backend.store_translations "en", activerecord: { attributes: { restricted_with_error_firm: { companies: "client companies" } } }
+    firm = RestrictedWithErrorFirm.create!(name: "restrict")
+    firm.companies.create(name: "child")
 
     assert !firm.companies.empty?
 
@@ -1520,8 +1667,8 @@ class HasManyAssociationsTest < ActiveRecord::TestCase
     assert !firm.errors.empty?
 
     assert_equal "Cannot delete record because dependent client companies exist", firm.errors[:base].first
-    assert RestrictedWithErrorFirm.exists?(name: 'restrict')
-    assert firm.companies.exists?(name: 'child')
+    assert RestrictedWithErrorFirm.exists?(name: "restrict")
+    assert firm.companies.exists?(name: "child")
   ensure
     I18n.backend.reload!
   end
@@ -1531,10 +1678,10 @@ class HasManyAssociationsTest < ActiveRecord::TestCase
   end
 
   def test_included_in_collection_for_new_records
-    client = Client.create(:name => 'Persisted')
+    client = Client.create(name: "Persisted")
     assert_nil client.client_of
     assert_equal false, Firm.new.clients_of_firm.include?(client),
-     'includes a client that does not belong to any firm'
+     "includes a client that does not belong to any firm"
   end
 
   def test_adding_array_and_collection
@@ -1542,7 +1689,7 @@ class HasManyAssociationsTest < ActiveRecord::TestCase
   end
 
   def test_replace_with_less
-    firm = Firm.all.merge!(:order => "id").first
+    firm = Firm.first
     firm.clients = [companies(:first_client)]
     assert firm.save, "Could not save firm"
     firm.reload
@@ -1556,7 +1703,7 @@ class HasManyAssociationsTest < ActiveRecord::TestCase
   end
 
   def test_replace_with_new
-    firm = Firm.all.merge!(:order => "id").first
+    firm = Firm.first
     firm.clients = [companies(:second_client), Client.new("name" => "New Client")]
     firm.save
     firm.reload
@@ -1589,12 +1736,12 @@ class HasManyAssociationsTest < ActiveRecord::TestCase
       firm.clients = []
     end
 
-    assert_equal [], firm.send('clients=', [])
+    assert_equal [], firm.send("clients=", [])
   end
 
   def test_transactions_when_replacing_on_persisted
-    good = Client.new(:name => "Good")
-    bad  = Client.new(:name => "Bad", :raise_on_save => true)
+    good = Client.new(name: "Good")
+    bad  = Client.new(name: "Bad", raise_on_save: true)
 
     companies(:first_firm).clients_of_firm = [good]
 
@@ -1633,6 +1780,11 @@ class HasManyAssociationsTest < ActiveRecord::TestCase
     assert !company.clients.loaded?
   end
 
+  def test_counter_cache_on_unloaded_association
+    car = Car.create(name: "My AppliCar")
+    assert_equal car.engines.size, 0
+  end
+
   def test_get_ids_ignores_include_option
     assert_equal [readers(:michael_welcome).id], posts(:welcome).readers_with_person_ids
   end
@@ -1657,7 +1809,7 @@ class HasManyAssociationsTest < ActiveRecord::TestCase
     contract_a = Contract.create!
     contract_b = Contract.create!
     Contract.create! # another contract
-    company = Company.new(:name => "Some Company")
+    company = Company.new(name: "Some Company")
 
     company.contract_ids = [contract_a.id, contract_b.id]
     assert_equal [contract_a.id, contract_b.id], company.contract_ids
@@ -1669,8 +1821,8 @@ class HasManyAssociationsTest < ActiveRecord::TestCase
   end
 
   def test_assign_ids_ignoring_blanks
-    firm = Firm.create!(:name => 'Apple')
-    firm.client_ids = [companies(:first_client).id, nil, companies(:second_client).id, '']
+    firm = Firm.create!(name: "Apple")
+    firm.client_ids = [companies(:first_client).id, nil, companies(:second_client).id, ""]
     firm.save!
 
     assert_equal 2, firm.clients.reload.size
@@ -1685,14 +1837,14 @@ class HasManyAssociationsTest < ActiveRecord::TestCase
     [
       lambda { authors(:mary).comment_ids = [comments(:greetings).id, comments(:more_greetings).id] },
       lambda { authors(:mary).comments = [comments(:greetings), comments(:more_greetings)] },
-      lambda { authors(:mary).comments << Comment.create!(:body => "Yay", :post_id => 424242) },
+      lambda { authors(:mary).comments << Comment.create!(body: "Yay", post_id: 424242) },
       lambda { authors(:mary).comments.delete(authors(:mary).comments.first) },
-    ].each {|block| assert_raise(ActiveRecord::HasManyThroughCantAssociateThroughHasOneOrManyReflection, &block) }
+    ].each { |block| assert_raise(ActiveRecord::HasManyThroughCantAssociateThroughHasOneOrManyReflection, &block) }
   end
 
   def test_dynamic_find_should_respect_association_order_for_through
     assert_equal Comment.find(10), authors(:david).comments_desc.where("comments.type = 'SpecialComment'").first
-    assert_equal Comment.find(10), authors(:david).comments_desc.find_by_type('SpecialComment')
+    assert_equal Comment.find(10), authors(:david).comments_desc.find_by_type("SpecialComment")
   end
 
   def test_has_many_through_respects_hash_conditions
@@ -1726,7 +1878,7 @@ class HasManyAssociationsTest < ActiveRecord::TestCase
 
   def test_include_returns_false_for_non_matching_record_to_verify_scoping
     firm = companies(:first_firm)
-    client = Client.create!(:name => 'Not Associated')
+    client = Client.create!(name: "Not Associated")
 
     assert ! firm.clients.loaded?
     assert_equal false, firm.clients.include?(client)
@@ -1755,7 +1907,7 @@ class HasManyAssociationsTest < ActiveRecord::TestCase
 
   def test_calling_first_or_last_on_existing_record_with_build_should_load_association
     firm = companies(:first_firm)
-    firm.clients.build(:name => 'Foo')
+    firm.clients.build(name: "Foo")
     assert !firm.clients.loaded?
 
     assert_queries 1 do
@@ -1769,7 +1921,7 @@ class HasManyAssociationsTest < ActiveRecord::TestCase
 
   def test_calling_first_nth_or_last_on_existing_record_with_create_should_not_load_association
     firm = companies(:first_firm)
-    firm.clients.create(:name => 'Foo')
+    firm.clients.create(name: "Foo")
     assert !firm.clients.loaded?
 
     assert_queries 3 do
@@ -1793,7 +1945,7 @@ class HasManyAssociationsTest < ActiveRecord::TestCase
 
   def test_calling_first_or_last_with_integer_on_association_should_not_load_association
     firm = companies(:first_firm)
-    firm.clients.create(:name => 'Foo')
+    firm.clients.create(name: "Foo")
     assert !firm.clients.loaded?
 
     assert_queries 2 do
@@ -1814,7 +1966,7 @@ class HasManyAssociationsTest < ActiveRecord::TestCase
 
   def test_calling_many_on_loaded_association_should_not_use_query
     firm = companies(:first_firm)
-    firm.clients.collect  # force load
+    firm.clients.load  # force load
     assert_no_queries { assert firm.clients.many? }
   end
 
@@ -1853,7 +2005,7 @@ class HasManyAssociationsTest < ActiveRecord::TestCase
 
   def test_calling_none_on_loaded_association_should_not_use_query
     firm = companies(:first_firm)
-    firm.clients.collect  # force load
+    firm.clients.load  # force load
     assert_no_queries { assert ! firm.clients.none? }
   end
 
@@ -1888,7 +2040,7 @@ class HasManyAssociationsTest < ActiveRecord::TestCase
 
   def test_calling_one_on_loaded_association_should_not_use_query
     firm = companies(:first_firm)
-    firm.clients.collect  # force load
+    firm.clients.load  # force load
     assert_no_queries { assert ! firm.clients.one? }
   end
 
@@ -1923,13 +2075,13 @@ class HasManyAssociationsTest < ActiveRecord::TestCase
     old = ActiveRecord::Base.store_full_sti_class
     ActiveRecord::Base.store_full_sti_class = true
 
-    firm = Namespaced::Firm.create({ :name => 'Some Company' })
-    firm.clients.create({ :name => 'Some Client' })
+    firm = Namespaced::Firm.create(name: "Some Company")
+    firm.clients.create(name: "Some Client")
 
     stats = Namespaced::Firm.all.merge!(
-      :select => "#{Namespaced::Firm.table_name}.id, COUNT(#{Namespaced::Client.table_name}.id) AS num_clients",
-      :joins  => :clients,
-      :group  => "#{Namespaced::Firm.table_name}.id"
+      select: "#{Namespaced::Firm.table_name}.id, COUNT(#{Namespaced::Client.table_name}.id) AS num_clients",
+      joins: :clients,
+      group: "#{Namespaced::Firm.table_name}.id"
     ).find firm.id
     assert_equal 1, stats.num_clients.to_i
   ensure
@@ -1948,15 +2100,9 @@ class HasManyAssociationsTest < ActiveRecord::TestCase
     assert_equal client_association.new.attributes, client_association.send(:new).attributes
   end
 
-  def test_respond_to_private_class_methods
-    client_association = companies(:first_firm).clients
-    assert !client_association.respond_to?(:private_method)
-    assert client_association.respond_to?(:private_method, true)
-  end
-
   def test_creating_using_primary_key
-    firm = Firm.all.merge!(:order => "id").first
-    client = firm.clients_using_primary_key.create!(:name => 'test')
+    firm = Firm.first
+    client = firm.clients_using_primary_key.create!(name: "test")
     assert_equal firm.name, client.firm_name
   end
 
@@ -1979,12 +2125,12 @@ class HasManyAssociationsTest < ActiveRecord::TestCase
   end
 
   def test_attributes_are_being_set_when_initialized_from_has_many_association_with_where_clause
-    new_comment = posts(:welcome).comments.where(:body => "Some content").build
+    new_comment = posts(:welcome).comments.where(body: "Some content").build
     assert_equal new_comment.body, "Some content"
   end
 
   def test_attributes_are_being_set_when_initialized_from_has_many_association_with_multiple_where_clauses
-    new_comment = posts(:welcome).comments.where(:body => "Some content").where(:type => 'SpecialComment').build
+    new_comment = posts(:welcome).comments.where(body: "Some content").where(type: "SpecialComment").build
     assert_equal new_comment.body, "Some content"
     assert_equal new_comment.type, "SpecialComment"
     assert_equal new_comment.post_id, posts(:welcome).id
@@ -1998,7 +2144,7 @@ class HasManyAssociationsTest < ActiveRecord::TestCase
 
   def test_load_target_respects_protected_attributes
     topic = Topic.create!
-    reply = topic.replies.create(:title => "reply 1")
+    reply = topic.replies.create(title: "reply 1")
     reply.approved = false
     reply.save!
 
@@ -2025,7 +2171,7 @@ class HasManyAssociationsTest < ActiveRecord::TestCase
   end
 
   def test_merging_with_custom_attribute_writer
-    bulb = Bulb.new(:color => "red")
+    bulb = Bulb.new(color: "red")
     assert_equal "RED!", bulb.color
 
     car = Car.create!
@@ -2035,13 +2181,13 @@ class HasManyAssociationsTest < ActiveRecord::TestCase
   end
 
   def test_abstract_class_with_polymorphic_has_many
-    post = SubStiPost.create! :title => "fooo", :body => "baa"
-    tagging = Tagging.create! :taggable => post
+    post = SubStiPost.create! title: "fooo", body: "baa"
+    tagging = Tagging.create! taggable: post
     assert_equal [tagging], post.taggings
   end
 
   def test_with_polymorphic_has_many_with_custom_columns_name
-    post = Post.create! :title => 'foo', :body => 'bar'
+    post = Post.create! title: "foo", body: "bar"
     image = Image.create!
 
     post.images << image
@@ -2051,10 +2197,17 @@ class HasManyAssociationsTest < ActiveRecord::TestCase
 
   def test_build_with_polymorphic_has_many_does_not_allow_to_override_type_and_id
     welcome = posts(:welcome)
-    tagging = welcome.taggings.build(:taggable_id => 99, :taggable_type => 'ShouldNotChange')
+    tagging = welcome.taggings.build(taggable_id: 99, taggable_type: "ShouldNotChange")
 
     assert_equal welcome.id, tagging.taggable_id
-    assert_equal 'Post', tagging.taggable_type
+    assert_equal "Post", tagging.taggable_type
+  end
+
+  def test_build_from_polymorphic_association_sets_inverse_instance
+    post = Post.new
+    tagging = post.taggings.build
+
+    assert_equal post, tagging.taggable
   end
 
   def test_dont_call_save_callbacks_twice_on_has_many
@@ -2066,30 +2219,30 @@ class HasManyAssociationsTest < ActiveRecord::TestCase
   end
 
   def test_association_attributes_are_available_to_after_initialize
-    car = Car.create(:name => 'honda')
+    car = Car.create(name: "honda")
     bulb = car.bulbs.build
 
-    assert_equal car.id, bulb.attributes_after_initialize['car_id']
+    assert_equal car.id, bulb.attributes_after_initialize["car_id"]
   end
 
   def test_attributes_are_set_when_initialized_from_has_many_null_relationship
-    car  = Car.new name: 'honda'
-    bulb = car.bulbs.where(name: 'headlight').first_or_initialize
-    assert_equal 'headlight', bulb.name
+    car  = Car.new name: "honda"
+    bulb = car.bulbs.where(name: "headlight").first_or_initialize
+    assert_equal "headlight", bulb.name
   end
 
   def test_attributes_are_set_when_initialized_from_polymorphic_has_many_null_relationship
-    post    = Post.new title: 'title', body: 'bar'
-    tag     = Tag.create!(name: 'foo')
+    post    = Post.new title: "title", body: "bar"
+    tag     = Tag.create!(name: "foo")
 
     tagging = post.taggings.where(tag: tag).first_or_initialize
 
     assert_equal tag.id, tagging.tag_id
-    assert_equal 'Post', tagging.taggable_type
+    assert_equal "Post", tagging.taggable_type
   end
 
   def test_replace
-    car = Car.create(:name => 'honda')
+    car = Car.create(name: "honda")
     bulb1 = car.bulbs.create
     bulb2 = Bulb.create
 
@@ -2100,7 +2253,7 @@ class HasManyAssociationsTest < ActiveRecord::TestCase
   end
 
   def test_replace_returns_target
-    car = Car.create(:name => 'honda')
+    car = Car.create(name: "honda")
     bulb1 = car.bulbs.create
     bulb2 = car.bulbs.create
     bulb3 = Bulb.create
@@ -2117,15 +2270,15 @@ class HasManyAssociationsTest < ActiveRecord::TestCase
   end
 
   test "first_or_initialize adds the record to the association" do
-    firm = Firm.create! name: 'omg'
+    firm = Firm.create! name: "omg"
     client = firm.clients_of_firm.first_or_initialize
     assert_equal [client], firm.clients_of_firm
   end
 
   test "first_or_create adds the record to the association" do
-    firm = Firm.create! name: 'omg'
+    firm = Firm.create! name: "omg"
     firm.clients_of_firm.load_target
-    client = firm.clients_of_firm.first_or_create name: 'lol'
+    client = firm.clients_of_firm.first_or_create name: "lol"
     assert_equal [client], firm.clients_of_firm
     assert_equal [client], firm.reload.clients_of_firm
   end
@@ -2147,7 +2300,7 @@ class HasManyAssociationsTest < ActiveRecord::TestCase
 
     assert_no_queries(ignore_none: false) do
       assert_equal [], post.comments
-      assert_equal [], post.comments.where(body: 'omg')
+      assert_equal [], post.comments.where(body: "omg")
       assert_equal [], post.comments.pluck(:body)
       assert_equal 0,  post.comments.sum(:id)
       assert_equal 0,  post.comments.count
@@ -2168,14 +2321,22 @@ class HasManyAssociationsTest < ActiveRecord::TestCase
   test "association with extend option with multiple extensions" do
     post = posts(:welcome)
     assert_equal "lifo",  post.comments_with_extend_2.author
-    assert_equal "hello", post.comments_with_extend_2.greeting
+    assert_equal "hullo", post.comments_with_extend_2.greeting
+  end
+
+  test "extend option affects per association" do
+    post = posts(:welcome)
+    assert_equal "lifo",  post.comments_with_extend.author
+    assert_equal "lifo",  post.comments_with_extend_2.author
+    assert_equal "hello", post.comments_with_extend.greeting
+    assert_equal "hullo", post.comments_with_extend_2.greeting
   end
 
   test "delete record with complex joins" do
     david = authors(:david)
 
     post = david.posts.first
-    post.type = 'PostWithSpecialCategorization'
+    post.type = "PostWithSpecialCategorization"
     post.save
 
     categorization = post.categorizations.first
@@ -2188,8 +2349,8 @@ class HasManyAssociationsTest < ActiveRecord::TestCase
   end
 
   test "does not duplicate associations when used with natural primary keys" do
-    speedometer = Speedometer.create!(id: '4')
-    speedometer.minivans.create!(minivan_id: 'a-van-red' ,name: 'a van', color: 'red')
+    speedometer = Speedometer.create!(id: "4")
+    speedometer.minivans.create!(minivan_id: "a-van-red", name: "a van", color: "red")
 
     assert_equal 1, speedometer.minivans.to_a.size, "Only one association should be present:\n#{speedometer.minivans.to_a}"
     assert_equal 1, speedometer.reload.minivans.to_a.size
@@ -2205,7 +2366,7 @@ class HasManyAssociationsTest < ActiveRecord::TestCase
   end
 
   test "can unscope and where the default scope of the associated model" do
-    Car.has_many :other_bulbs, -> { unscope(where: [:name]).where(name: 'other') }, class_name: "Bulb"
+    Car.has_many :other_bulbs, -> { unscope(where: [:name]).where(name: "other") }, class_name: "Bulb"
     car = Car.create!
     bulb1 = Bulb.create! name: "defaulty", car: car
     bulb2 = Bulb.create! name: "other",    car: car
@@ -2215,7 +2376,7 @@ class HasManyAssociationsTest < ActiveRecord::TestCase
   end
 
   test "can rewhere the default scope of the associated model" do
-    Car.has_many :old_bulbs, -> { rewhere(name: 'old') }, class_name: "Bulb"
+    Car.has_many :old_bulbs, -> { rewhere(name: "old") }, class_name: "Bulb"
     car = Car.create!
     bulb1 = Bulb.create! name: "defaulty", car: car
     bulb2 = Bulb.create! name: "old",      car: car
@@ -2224,12 +2385,13 @@ class HasManyAssociationsTest < ActiveRecord::TestCase
     assert_equal [bulb2], car.old_bulbs
   end
 
-  test 'unscopes the default scope of associated model when used with include' do
+  test "unscopes the default scope of associated model when used with include" do
     car = Car.create!
     bulb = Bulb.create! name: "other", car: car
 
-    assert_equal bulb, Car.find(car.id).all_bulbs.first
-    assert_equal bulb, Car.includes(:all_bulbs).find(car.id).all_bulbs.first
+    assert_equal [bulb], Car.find(car.id).all_bulbs
+    assert_equal [bulb], Car.includes(:all_bulbs).find(car.id).all_bulbs
+    assert_equal [bulb], Car.eager_load(:all_bulbs).find(car.id).all_bulbs
   end
 
   test "raises RecordNotDestroyed when replaced child can't be destroyed" do
@@ -2244,7 +2406,7 @@ class HasManyAssociationsTest < ActiveRecord::TestCase
     assert_equal "Failed to destroy the record", error.message
   end
 
-  test 'updates counter cache when default scope is given' do
+  test "updates counter cache when default scope is given" do
     topic = DefaultRejectedTopic.create approved: true
 
     assert_difference "topic.reload.replies_count", 1 do
@@ -2252,8 +2414,8 @@ class HasManyAssociationsTest < ActiveRecord::TestCase
     end
   end
 
-  test 'dangerous association name raises ArgumentError' do
-    [:errors, 'errors', :save, 'save'].each do |name|
+  test "dangerous association name raises ArgumentError" do
+    [:errors, "errors", :save, "save"].each do |name|
       assert_raises(ArgumentError, "Association #{name} should not be allowed") do
         Class.new(ActiveRecord::Base) do
           has_many name
@@ -2262,7 +2424,7 @@ class HasManyAssociationsTest < ActiveRecord::TestCase
     end
   end
 
-  test 'passes custom context validation to validate children' do
+  test "passes custom context validation to validate children" do
     pirate = FamousPirate.new
     pirate.famous_ships << ship = FamousShip.new
 
@@ -2271,7 +2433,7 @@ class HasManyAssociationsTest < ActiveRecord::TestCase
     assert_equal "can't be blank", ship.errors[:name].first
   end
 
-  test 'association with instance dependent scope' do
+  test "association with instance dependent scope" do
     bob = authors(:bob)
     Post.create!(title: "signed post by bob", body: "stuff", author: authors(:bob))
     Post.create!(title: "anonymous post", body: "more stuff", author: authors(:bob))
@@ -2281,7 +2443,7 @@ class HasManyAssociationsTest < ActiveRecord::TestCase
     assert_equal [], authors(:david).posts_with_signature.map(&:title)
   end
 
-  test 'associations autosaves when object is already persisted' do
+  test "associations autosaves when object is already persisted" do
     bulb = Bulb.create!
     tyre = Tyre.create!
 
@@ -2294,7 +2456,7 @@ class HasManyAssociationsTest < ActiveRecord::TestCase
     assert_equal 1, car.tyres.count
   end
 
-  test 'associations replace in memory when records have the same id' do
+  test "associations replace in memory when records have the same id" do
     bulb = Bulb.create!
     car = Car.create!(bulbs: [bulb])
 
@@ -2305,7 +2467,7 @@ class HasManyAssociationsTest < ActiveRecord::TestCase
     assert_equal "foo", car.bulbs.first.name
   end
 
-  test 'in memory replacement executes no queries' do
+  test "in memory replacement executes no queries" do
     bulb = Bulb.create!
     car = Car.create!(bulbs: [bulb])
 
@@ -2316,7 +2478,7 @@ class HasManyAssociationsTest < ActiveRecord::TestCase
     end
   end
 
-  test 'in memory replacements do not execute callbacks' do
+  test "in memory replacements do not execute callbacks" do
     raise_after_add = false
     klass = Class.new(ActiveRecord::Base) do
       self.table_name = :cars
@@ -2337,7 +2499,7 @@ class HasManyAssociationsTest < ActiveRecord::TestCase
     end
   end
 
-  test 'in memory replacements sets inverse instance' do
+  test "in memory replacements sets inverse instance" do
     bulb = Bulb.create!
     car = Car.create!(bulbs: [bulb])
 
@@ -2347,7 +2509,16 @@ class HasManyAssociationsTest < ActiveRecord::TestCase
     assert_same car, new_bulb.car
   end
 
-  test 'in memory replacement maintains order' do
+  test "reattach to new objects replaces inverse association and foreign key" do
+    bulb = Bulb.create!(car: Car.create!)
+    assert bulb.car_id
+    car = Car.new
+    car.bulbs << bulb
+    assert_equal car, bulb.car
+    assert_nil bulb.car_id
+  end
+
+  test "in memory replacement maintains order" do
     first_bulb = Bulb.create!
     second_bulb = Bulb.create!
     car = Car.create!(bulbs: [first_bulb, second_bulb])
@@ -2358,16 +2529,35 @@ class HasManyAssociationsTest < ActiveRecord::TestCase
     assert_equal [first_bulb, second_bulb], car.bulbs
   end
 
-  test 'double insertion of new object to association when same association used in the after create callback of a new object' do
-    car = Car.create!
-    car.bulbs << TrickyBulb.new
-    assert_equal 1, car.bulbs.size
+  test "association size calculation works with default scoped selects when not previously fetched" do
+    firm = Firm.create!(name: "Firm")
+    5.times { firm.developers_with_select << Developer.create!(name: "Developer") }
+
+    same_firm = Firm.find(firm.id)
+    assert_equal 5, same_firm.developers_with_select.size
   end
 
-  def test_association_force_reload_with_only_true_is_deprecated
-    company = Company.find(1)
+  test "prevent double insertion of new object when the parent association loaded in the after save callback" do
+    reset_callbacks(:save, Bulb) do
+      Bulb.after_save { |record| record.car.bulbs.load }
 
-    assert_deprecated { company.clients_of_firm(true) }
+      car = Car.create!
+      car.bulbs << Bulb.new
+
+      assert_equal 1, car.bulbs.size
+    end
+  end
+
+  test "prevent double firing the before save callback of new object when the parent association saved in the callback" do
+    reset_callbacks(:save, Bulb) do
+      count = 0
+      Bulb.before_save { |record| record.car.save && count += 1 }
+
+      car = Car.create!
+      car.bulbs.create!
+
+      assert_equal 1, count
+    end
   end
 
   class AuthorWithErrorDestroyingAssociation < ActiveRecord::Base
@@ -2401,10 +2591,46 @@ class HasManyAssociationsTest < ActiveRecord::TestCase
   end
 
   def test_ids_reader_memoization
-    car = Car.create!(name: 'Tofaş')
+    car = Car.create!(name: "Tofaş")
     bulb = Bulb.create!(car: car)
 
     assert_equal [bulb.id], car.bulb_ids
     assert_no_queries { car.bulb_ids }
+
+    bulb2 = car.bulbs.create!
+
+    assert_equal [bulb.id, bulb2.id], car.bulb_ids
+    assert_no_queries { car.bulb_ids }
+  end
+
+  def test_loading_association_in_validate_callback_doesnt_affect_persistence
+    reset_callbacks(:validation, Bulb) do
+      Bulb.after_validation { |record| record.car.bulbs.load }
+
+      car = Car.create!(name: "Car")
+      bulb = car.bulbs.create!
+
+      assert_equal [bulb], car.bulbs
+    end
   end
+
+  private
+
+    def force_signal37_to_load_all_clients_of_firm
+      companies(:first_firm).clients_of_firm.load_target
+    end
+
+    def reset_callbacks(kind, klass)
+      old_callbacks = {}
+      old_callbacks[klass] = klass.send("_#{kind}_callbacks").dup
+      klass.subclasses.each do |subclass|
+        old_callbacks[subclass] = subclass.send("_#{kind}_callbacks").dup
+      end
+      yield
+    ensure
+      klass.send("_#{kind}_callbacks=", old_callbacks[klass])
+      klass.subclasses.each do |subclass|
+        subclass.send("_#{kind}_callbacks=", old_callbacks[subclass])
+      end
+    end
 end
diff --git a/activerecord/test/cases/associations/has_many_through_associations_test.rb b/activerecord/test/cases/associations/has_many_through_associations_test.rb
index aa35844a03..7c9c9e81ab 100644
--- a/activerecord/test/cases/associations/has_many_through_associations_test.rb
+++ b/activerecord/test/cases/associations/has_many_through_associations_test.rb
@@ -1,33 +1,38 @@
+# frozen_string_literal: true
+
 require "cases/helper"
-require 'models/post'
-require 'models/person'
-require 'models/reference'
-require 'models/job'
-require 'models/reader'
-require 'models/comment'
-require 'models/rating'
-require 'models/tag'
-require 'models/tagging'
-require 'models/author'
-require 'models/owner'
-require 'models/pet'
-require 'models/pet_treasure'
-require 'models/toy'
-require 'models/treasure'
-require 'models/contract'
-require 'models/company'
-require 'models/developer'
-require 'models/computer'
-require 'models/subscriber'
-require 'models/book'
-require 'models/subscription'
-require 'models/essay'
-require 'models/category'
-require 'models/categorization'
-require 'models/member'
-require 'models/membership'
-require 'models/club'
-require 'models/organization'
+require "models/post"
+require "models/person"
+require "models/reference"
+require "models/job"
+require "models/reader"
+require "models/comment"
+require "models/rating"
+require "models/tag"
+require "models/tagging"
+require "models/author"
+require "models/owner"
+require "models/pet"
+require "models/pet_treasure"
+require "models/toy"
+require "models/treasure"
+require "models/contract"
+require "models/company"
+require "models/developer"
+require "models/computer"
+require "models/subscriber"
+require "models/book"
+require "models/subscription"
+require "models/essay"
+require "models/category"
+require "models/categorization"
+require "models/member"
+require "models/membership"
+require "models/club"
+require "models/organization"
+require "models/user"
+require "models/family"
+require "models/family_tree"
 
 class HasManyThroughAssociationsTest < ActiveRecord::TestCase
   fixtures :posts, :readers, :people, :comments, :authors, :categories, :taggings, :tags,
@@ -37,8 +42,8 @@ class HasManyThroughAssociationsTest < ActiveRecord::TestCase
 
   # Dummies to force column loads so query counts are clean.
   def setup
-    Person.create :first_name => 'gummy'
-    Reader.create :person_id => 0, :post_id => 0
+    Person.create first_name: "gummy"
+    Reader.create person_id: 0, post_id: 0
   end
 
   def test_preload_sti_rhs_class
@@ -49,9 +54,9 @@ class HasManyThroughAssociationsTest < ActiveRecord::TestCase
   end
 
   def test_preload_sti_middle_relation
-    club = Club.create!(name: 'Aaron cool banana club')
-    member1 = Member.create!(name: 'Aaron')
-    member2 = Member.create!(name: 'Cat')
+    club = Club.create!(name: "Aaron cool banana club")
+    member1 = Member.create!(name: "Aaron")
+    member2 = Member.create!(name: "Cat")
 
     SuperMembership.create! club: club, member: member1
     CurrentMembership.create! club: club, member: member2
@@ -61,21 +66,17 @@ class HasManyThroughAssociationsTest < ActiveRecord::TestCase
                  club1.members.sort_by(&:id)
   end
 
-  def make_model(name)
-    Class.new(ActiveRecord::Base) { define_singleton_method(:name) { name } }
-  end
-
   def test_ordered_has_many_through
     person_prime = Class.new(ActiveRecord::Base) do
-      def self.name; 'Person'; end
+      def self.name; "Person"; end
 
       has_many :readers
-      has_many :posts, -> { order('posts.id DESC') }, :through => :readers
+      has_many :posts, -> { order("posts.id DESC") }, through: :readers
     end
     posts = person_prime.includes(:posts).first.posts
 
     assert_operator posts.length, :>, 1
-    posts.each_cons(2) do |left,right|
+    posts.each_cons(2) do |left, right|
       assert_operator left.id, :>, right.id
     end
   end
@@ -85,7 +86,7 @@ class HasManyThroughAssociationsTest < ActiveRecord::TestCase
     subscription = make_model "Subscription"
     subscriber   = make_model "Subscriber"
 
-    subscriber.primary_key = 'nick'
+    subscriber.primary_key = "nick"
     subscription.belongs_to :book,       anonymous_class: book
     subscription.belongs_to :subscriber, anonymous_class: subscriber
 
@@ -106,8 +107,8 @@ class HasManyThroughAssociationsTest < ActiveRecord::TestCase
   def test_no_pk_join_table_append
     lesson, _, student = make_no_pk_hm_t
 
-    sicp = lesson.new(:name => "SICP")
-    ben = student.new(:name => "Ben Bitdiddle")
+    sicp = lesson.new(name: "SICP")
+    ben = student.new(name: "Ben Bitdiddle")
     sicp.students << ben
     assert sicp.save!
   end
@@ -115,17 +116,17 @@ class HasManyThroughAssociationsTest < ActiveRecord::TestCase
   def test_no_pk_join_table_delete
     lesson, lesson_student, student = make_no_pk_hm_t
 
-    sicp = lesson.new(:name => "SICP")
-    ben = student.new(:name => "Ben Bitdiddle")
-    louis = student.new(:name => "Louis Reasoner")
+    sicp = lesson.new(name: "SICP")
+    ben = student.new(name: "Ben Bitdiddle")
+    louis = student.new(name: "Louis Reasoner")
     sicp.students << ben
     sicp.students << louis
     assert sicp.save!
 
     sicp.students.reload
     assert_operator lesson_student.count, :>=, 2
-    assert_no_difference('student.count') do
-      assert_difference('lesson_student.count', -2) do
+    assert_no_difference("student.count") do
+      assert_difference("lesson_student.count", -2) do
         sicp.students.destroy(*student.all.to_a)
       end
     end
@@ -139,8 +140,8 @@ class HasManyThroughAssociationsTest < ActiveRecord::TestCase
       after_destroy_called = true
     end
 
-    sicp = lesson.new(:name => "SICP")
-    ben = student.new(:name => "Ben Bitdiddle")
+    sicp = lesson.new(name: "SICP")
+    ben = student.new(name: "Ben Bitdiddle")
     sicp.students << ben
     assert sicp.save!
 
@@ -149,20 +150,6 @@ class HasManyThroughAssociationsTest < ActiveRecord::TestCase
     assert after_destroy_called, "after destroy should be called"
   end
 
-  def make_no_pk_hm_t
-    lesson = make_model 'Lesson'
-    student = make_model 'Student'
-
-    lesson_student = make_model 'LessonStudent'
-    lesson_student.table_name = 'lessons_students'
-
-    lesson_student.belongs_to :lesson, :anonymous_class => lesson
-    lesson_student.belongs_to :student, :anonymous_class => student
-    lesson.has_many :lesson_students, :anonymous_class => lesson_student
-    lesson.has_many :students, :through => :lesson_students, :anonymous_class => student
-    [lesson, lesson_student, student]
-  end
-
   def test_pk_is_not_required_for_join
     post  = Post.includes(:scategories).first
     post2 = Post.includes(:categories).first
@@ -175,7 +162,7 @@ class HasManyThroughAssociationsTest < ActiveRecord::TestCase
     person = Person.new
     post = Post.new
     person.posts << post
-    assert person.posts.include?(post)
+    assert_includes person.posts, post
   end
 
   def test_associate_existing
@@ -187,18 +174,18 @@ class HasManyThroughAssociationsTest < ActiveRecord::TestCase
     end
 
     assert_queries(1) do
-      assert post.people.include?(person)
+      assert_includes post.people, person
     end
 
-    assert post.reload.people.reload.include?(person)
+    assert_includes post.reload.people.reload, person
   end
 
   def test_delete_all_for_with_dependent_option_destroy
     person = people(:david)
     assert_equal 1, person.jobs_with_dependent_destroy.count
 
-    assert_no_difference 'Job.count' do
-      assert_difference 'Reference.count', -1 do
+    assert_no_difference "Job.count" do
+      assert_difference "Reference.count", -1 do
         person.reload.jobs_with_dependent_destroy.delete_all
       end
     end
@@ -208,8 +195,8 @@ class HasManyThroughAssociationsTest < ActiveRecord::TestCase
     person = people(:david)
     assert_equal 1, person.jobs_with_dependent_nullify.count
 
-    assert_no_difference 'Job.count' do
-      assert_no_difference 'Reference.count' do
+    assert_no_difference "Job.count" do
+      assert_no_difference "Reference.count" do
         person.reload.jobs_with_dependent_nullify.delete_all
       end
     end
@@ -219,8 +206,8 @@ class HasManyThroughAssociationsTest < ActiveRecord::TestCase
     person = people(:david)
     assert_equal 1, person.jobs_with_dependent_delete_all.count
 
-    assert_no_difference 'Job.count' do
-      assert_difference 'Reference.count', -1 do
+    assert_no_difference "Job.count" do
+      assert_difference "Reference.count", -1 do
         person.reload.jobs_with_dependent_delete_all.delete_all
       end
     end
@@ -238,7 +225,7 @@ class HasManyThroughAssociationsTest < ActiveRecord::TestCase
     post   = posts(:thinking)
     person = people(:david)
 
-    assert_difference 'post.people.to_a.count', 2 do
+    assert_difference "post.people.to_a.count", 2 do
       post.people << person
       post.people << person
     end
@@ -248,7 +235,7 @@ class HasManyThroughAssociationsTest < ActiveRecord::TestCase
     post   = posts(:thinking)
     person = people(:david)
 
-    assert_difference 'post.people.count', 2 do
+    assert_difference "post.people.count", 2 do
       post.people << person
       post.people << person
     end
@@ -261,12 +248,12 @@ class HasManyThroughAssociationsTest < ActiveRecord::TestCase
     post.people << person
     post.people << person
 
-    counts = ['post.people.count', 'post.people.to_a.count', 'post.readers.count', 'post.readers.to_a.count']
+    counts = ["post.people.count", "post.people.to_a.count", "post.readers.count", "post.readers.to_a.count"]
     assert_difference counts, -2 do
       post.people.delete(person)
     end
 
-    assert !post.people.reload.include?(person)
+    assert_not_includes post.people.reload, person
   end
 
   def test_associating_new
@@ -274,7 +261,7 @@ class HasManyThroughAssociationsTest < ActiveRecord::TestCase
     new_person = nil # so block binding catches it
 
     assert_queries(0) do
-      new_person = Person.new :first_name => 'bob'
+      new_person = Person.new first_name: "bob"
     end
 
     # Associating new records always saves them
@@ -284,59 +271,70 @@ class HasManyThroughAssociationsTest < ActiveRecord::TestCase
     end
 
     assert_queries(1) do
-      assert posts(:thinking).people.include?(new_person)
+      assert_includes posts(:thinking).people, new_person
     end
 
-    assert posts(:thinking).reload.people.reload.include?(new_person)
+    assert_includes posts(:thinking).reload.people.reload, new_person
   end
 
   def test_associate_new_by_building
     assert_queries(1) { posts(:thinking) }
 
     assert_queries(0) do
-      posts(:thinking).people.build(:first_name => "Bob")
-      posts(:thinking).people.new(:first_name => "Ted")
+      posts(:thinking).people.build(first_name: "Bob")
+      posts(:thinking).people.new(first_name: "Ted")
     end
 
     # Should only need to load the association once
     assert_queries(1) do
-      assert posts(:thinking).people.collect(&:first_name).include?("Bob")
-      assert posts(:thinking).people.collect(&:first_name).include?("Ted")
+      assert_includes posts(:thinking).people.collect(&:first_name), "Bob"
+      assert_includes posts(:thinking).people.collect(&:first_name), "Ted"
     end
 
     # 2 queries for each new record (1 to save the record itself, 1 for the join model)
     #    * 2 new records = 4
     # + 1 query to save the actual post = 5
     assert_queries(5) do
-      posts(:thinking).body += '-changed'
+      posts(:thinking).body += "-changed"
       posts(:thinking).save
     end
 
-    assert posts(:thinking).reload.people.reload.collect(&:first_name).include?("Bob")
-    assert posts(:thinking).reload.people.reload.collect(&:first_name).include?("Ted")
+    assert_includes posts(:thinking).reload.people.reload.collect(&:first_name), "Bob"
+    assert_includes posts(:thinking).reload.people.reload.collect(&:first_name), "Ted"
   end
 
   def test_build_then_save_with_has_many_inverse
     post   = posts(:thinking)
-    person = post.people.build(:first_name => "Bob")
+    person = post.people.build(first_name: "Bob")
     person.save
     post.reload
 
-    assert post.people.include?(person)
+    assert_includes post.people, person
   end
 
   def test_build_then_save_with_has_one_inverse
     post   = posts(:thinking)
-    person = post.single_people.build(:first_name => "Bob")
+    person = post.single_people.build(first_name: "Bob")
     person.save
     post.reload
 
-    assert post.single_people.include?(person)
+    assert_includes post.single_people, person
+  end
+
+  def test_build_then_remove_then_save
+    post = posts(:thinking)
+    post.people.build(first_name: "Bob")
+    ted = post.people.build(first_name: "Ted")
+    post.people.delete(ted)
+    post.save!
+    post.reload
+
+    assert_equal ["Bob"], post.people.collect(&:first_name)
   end
 
   def test_both_parent_ids_set_when_saving_new
-    post = Post.new(title: 'Hello', body: 'world')
-    person = Person.new(first_name: 'Sean')
+    post = Post.new(title: "Hello", body: "world")
+    person = Person.new(first_name: "Sean")
 
     post.people = [person]
     post.save
@@ -348,7 +346,7 @@ class HasManyThroughAssociationsTest < ActiveRecord::TestCase
   end
 
   def test_delete_association
-    assert_queries(2){posts(:welcome);people(:michael); }
+    assert_queries(2) { posts(:welcome);people(:michael); }
 
     assert_queries(1) do
       posts(:welcome).people.delete(people(:michael))
@@ -394,15 +392,15 @@ class HasManyThroughAssociationsTest < ActiveRecord::TestCase
 
     person    = people(:michael)
     job       = jobs(:magician)
-    reference = Reference.where(:job_id => job.id, :person_id => person.id).first
+    reference = Reference.where(job_id: job.id, person_id: person.id).first
 
-    assert_no_difference ['Job.count', 'Reference.count'] do
-      assert_difference 'person.jobs.count', -1 do
+    assert_no_difference ["Job.count", "Reference.count"] do
+      assert_difference "person.jobs.count", -1 do
         person.jobs_with_dependent_nullify.delete(job)
       end
     end
 
-    assert_equal nil, reference.reload.job_id
+    assert_nil reference.reload.job_id
   ensure
     Reference.make_comments = false
   end
@@ -416,14 +414,14 @@ class HasManyThroughAssociationsTest < ActiveRecord::TestCase
     # Make sure we're not deleting everything
     assert person.jobs.count >= 2
 
-    assert_no_difference 'Job.count' do
-      assert_difference ['person.jobs.count', 'Reference.count'], -1 do
+    assert_no_difference "Job.count" do
+      assert_difference ["person.jobs.count", "Reference.count"], -1 do
         person.jobs_with_dependent_delete_all.delete(job)
       end
     end
 
     # Check that the destroy callback on Reference did not run
-    assert_equal nil, person.reload.comments
+    assert_nil person.reload.comments
   ensure
     Reference.make_comments = false
   end
@@ -437,8 +435,8 @@ class HasManyThroughAssociationsTest < ActiveRecord::TestCase
     # Make sure we're not deleting everything
     assert person.jobs.count >= 2
 
-    assert_no_difference 'Job.count' do
-      assert_difference ['person.jobs.count', 'Reference.count'], -1 do
+    assert_no_difference "Job.count" do
+      assert_difference ["person.jobs.count", "Reference.count"], -1 do
         person.jobs_with_dependent_destroy.delete(job)
       end
     end
@@ -455,8 +453,8 @@ class HasManyThroughAssociationsTest < ActiveRecord::TestCase
     # Create a reference which is not linked to a job. This should not be destroyed.
     person.references.create!
 
-    assert_no_difference 'Job.count' do
-      assert_difference 'Reference.count', -person.jobs.count do
+    assert_no_difference "Job.count" do
+      assert_difference "Reference.count", -person.jobs.count do
         person.destroy
       end
     end
@@ -468,8 +466,8 @@ class HasManyThroughAssociationsTest < ActiveRecord::TestCase
     # Create a reference which is not linked to a job. This should not be destroyed.
     person.references.create!
 
-    assert_no_difference 'Job.count' do
-      assert_difference 'Reference.count', -person.jobs.count do
+    assert_no_difference "Job.count" do
+      assert_difference "Reference.count", -person.jobs.count do
         person.destroy
       end
     end
@@ -480,41 +478,41 @@ class HasManyThroughAssociationsTest < ActiveRecord::TestCase
 
     references = person.references.to_a
 
-    assert_no_difference ['Reference.count', 'Job.count'] do
+    assert_no_difference ["Reference.count", "Job.count"] do
       person.destroy
     end
 
     references.each do |reference|
-      assert_equal nil, reference.reload.job_id
+      assert_nil reference.reload.job_id
     end
   end
 
   def test_update_counter_caches_on_delete
     post = posts(:welcome)
-    tag  = post.tags.create!(:name => 'doomed')
+    tag  = post.tags.create!(name: "doomed")
 
-    assert_difference ['post.reload.tags_count'], -1 do
+    assert_difference ["post.reload.tags_count"], -1 do
       posts(:welcome).tags.delete(tag)
     end
   end
 
   def test_update_counter_caches_on_delete_with_dependent_destroy
     post = posts(:welcome)
-    tag  = post.tags.create!(:name => 'doomed')
+    tag  = post.tags.create!(name: "doomed")
     post.update_columns(tags_with_destroy_count: post.tags.count)
 
-    assert_difference ['post.reload.tags_with_destroy_count'], -1 do
+    assert_difference ["post.reload.tags_with_destroy_count"], -1 do
       posts(:welcome).tags_with_destroy.delete(tag)
     end
   end
 
   def test_update_counter_caches_on_delete_with_dependent_nullify
     post = posts(:welcome)
-    tag  = post.tags.create!(:name => 'doomed')
+    tag  = post.tags.create!(name: "doomed")
     post.update_columns(tags_with_nullify_count: post.tags.count)
 
-    assert_no_difference 'post.reload.tags_count' do
-      assert_difference 'post.reload.tags_with_nullify_count', -1 do
+    assert_no_difference "post.reload.tags_count" do
+      assert_difference "post.reload.tags_with_nullify_count", -1 do
         posts(:welcome).tags_with_nullify.delete(tag)
       end
     end
@@ -522,7 +520,7 @@ class HasManyThroughAssociationsTest < ActiveRecord::TestCase
 
   def test_update_counter_caches_on_replace_association
     post = posts(:welcome)
-    tag  = post.tags.create!(:name => 'doomed')
+    tag  = post.tags.create!(name: "doomed")
     tag.tagged_posts << posts(:thinking)
 
     tag.tagged_posts = []
@@ -533,15 +531,15 @@ class HasManyThroughAssociationsTest < ActiveRecord::TestCase
 
   def test_update_counter_caches_on_destroy
     post = posts(:welcome)
-    tag  = post.tags.create!(name: 'doomed')
+    tag  = post.tags.create!(name: "doomed")
 
-    assert_difference 'post.reload.tags_count', -1 do
+    assert_difference "post.reload.tags_count", -1 do
       tag.tagged_posts.destroy(post)
     end
   end
 
   def test_replace_association
-    assert_queries(4){posts(:welcome);people(:david);people(:michael); posts(:welcome).people.reload}
+    assert_queries(4) { posts(:welcome);people(:david);people(:michael); posts(:welcome).people.reload }
 
     # 1 query to delete the existing reader (michael)
     # 1 query to associate the new reader (david)
@@ -549,35 +547,35 @@ class HasManyThroughAssociationsTest < ActiveRecord::TestCase
       posts(:welcome).people = [people(:david)]
     end
 
-    assert_queries(0){
-      assert posts(:welcome).people.include?(people(:david))
-      assert !posts(:welcome).people.include?(people(:michael))
+    assert_queries(0) {
+      assert_includes posts(:welcome).people, people(:david)
+      assert_not_includes posts(:welcome).people, people(:michael)
     }
 
-    assert posts(:welcome).reload.people.reload.include?(people(:david))
-    assert !posts(:welcome).reload.people.reload.include?(people(:michael))
+    assert_includes posts(:welcome).reload.people.reload, people(:david)
+    assert_not_includes posts(:welcome).reload.people.reload, people(:michael)
   end
 
   def test_replace_order_is_preserved
     posts(:welcome).people.clear
     posts(:welcome).people = [people(:david), people(:michael)]
-    assert_equal [people(:david).id, people(:michael).id], posts(:welcome).readers.order('id').map(&:person_id)
+    assert_equal [people(:david).id, people(:michael).id], posts(:welcome).readers.order("id").map(&:person_id)
 
     # Test the inverse order in case the first success was a coincidence
     posts(:welcome).people.clear
     posts(:welcome).people = [people(:michael), people(:david)]
-    assert_equal [people(:michael).id, people(:david).id], posts(:welcome).readers.order('id').map(&:person_id)
+    assert_equal [people(:michael).id, people(:david).id], posts(:welcome).readers.order("id").map(&:person_id)
   end
 
   def test_replace_by_id_order_is_preserved
     posts(:welcome).people.clear
     posts(:welcome).person_ids = [people(:david).id, people(:michael).id]
-    assert_equal [people(:david).id, people(:michael).id], posts(:welcome).readers.order('id').map(&:person_id)
+    assert_equal [people(:david).id, people(:michael).id], posts(:welcome).readers.order("id").map(&:person_id)
 
     # Test the inverse order in case the first success was a coincidence
     posts(:welcome).people.clear
     posts(:welcome).person_ids = [people(:michael).id, people(:david).id]
-    assert_equal [people(:michael).id, people(:david).id], posts(:welcome).readers.order('id').map(&:person_id)
+    assert_equal [people(:michael).id, people(:david).id], posts(:welcome).readers.order("id").map(&:person_id)
   end
 
   def test_associate_with_create
@@ -586,15 +584,15 @@ class HasManyThroughAssociationsTest < ActiveRecord::TestCase
     # 1 query for the new record, 1 for the join table record
     # No need to update the actual collection yet!
     assert_queries(2) do
-      posts(:thinking).people.create(:first_name=>"Jeb")
+      posts(:thinking).people.create(first_name: "Jeb")
     end
 
     # *Now* we actually need the collection so it's loaded
     assert_queries(1) do
-      assert posts(:thinking).people.collect(&:first_name).include?("Jeb")
+      assert_includes posts(:thinking).people.collect(&:first_name), "Jeb"
     end
 
-    assert posts(:thinking).reload.people.reload.collect(&:first_name).include?("Jeb")
+    assert_includes posts(:thinking).reload.people.reload.collect(&:first_name), "Jeb"
   end
 
   def test_through_record_is_built_when_created_with_where
@@ -605,66 +603,66 @@ class HasManyThroughAssociationsTest < ActiveRecord::TestCase
 
   def test_associate_with_create_and_no_options
     peeps = posts(:thinking).people.count
-    posts(:thinking).people.create(:first_name => 'foo')
+    posts(:thinking).people.create(first_name: "foo")
     assert_equal peeps + 1, posts(:thinking).people.count
   end
 
   def test_associate_with_create_with_through_having_conditions
     impatient_people = posts(:thinking).impatient_people.count
-    posts(:thinking).impatient_people.create!(:first_name => 'foo')
+    posts(:thinking).impatient_people.create!(first_name: "foo")
     assert_equal impatient_people + 1, posts(:thinking).impatient_people.count
   end
 
   def test_associate_with_create_exclamation_and_no_options
     peeps = posts(:thinking).people.count
-    posts(:thinking).people.create!(:first_name => 'foo')
+    posts(:thinking).people.create!(first_name: "foo")
     assert_equal peeps + 1, posts(:thinking).people.count
   end
 
   def test_create_on_new_record
     p = Post.new
 
-    error = assert_raises(ActiveRecord::RecordNotSaved) { p.people.create(:first_name => "mew") }
+    error = assert_raises(ActiveRecord::RecordNotSaved) { p.people.create(first_name: "mew") }
     assert_equal "You cannot call create unless the parent is saved", error.message
 
-    error = assert_raises(ActiveRecord::RecordNotSaved) { p.people.create!(:first_name => "snow") }
+    error = assert_raises(ActiveRecord::RecordNotSaved) { p.people.create!(first_name: "snow") }
     assert_equal "You cannot call create unless the parent is saved", error.message
   end
 
   def test_associate_with_create_and_invalid_options
     firm = companies(:first_firm)
-    assert_no_difference('firm.developers.count') { assert_nothing_raised { firm.developers.create(:name => '0') } }
+    assert_no_difference("firm.developers.count") { assert_nothing_raised { firm.developers.create(name: "0") } }
   end
 
   def test_associate_with_create_and_valid_options
     firm = companies(:first_firm)
-    assert_difference('firm.developers.count', 1) { firm.developers.create(:name => 'developer') }
+    assert_difference("firm.developers.count", 1) { firm.developers.create(name: "developer") }
   end
 
   def test_associate_with_create_bang_and_invalid_options
     firm = companies(:first_firm)
-    assert_no_difference('firm.developers.count') { assert_raises(ActiveRecord::RecordInvalid) { firm.developers.create!(:name => '0') } }
+    assert_no_difference("firm.developers.count") { assert_raises(ActiveRecord::RecordInvalid) { firm.developers.create!(name: "0") } }
   end
 
   def test_associate_with_create_bang_and_valid_options
     firm = companies(:first_firm)
-    assert_difference('firm.developers.count', 1) { firm.developers.create!(:name => 'developer') }
+    assert_difference("firm.developers.count", 1) { firm.developers.create!(name: "developer") }
   end
 
   def test_push_with_invalid_record
     firm = companies(:first_firm)
-    assert_raises(ActiveRecord::RecordInvalid) { firm.developers << Developer.new(:name => '0') }
+    assert_raises(ActiveRecord::RecordInvalid) { firm.developers << Developer.new(name: "0") }
   end
 
   def test_push_with_invalid_join_record
     repair_validations(Contract) do
-      Contract.validate {|r| r.errors[:base] << 'Invalid Contract' }
+      Contract.validate { |r| r.errors[:base] << "Invalid Contract" }
 
       firm = companies(:first_firm)
-      lifo = Developer.new(:name => 'lifo')
+      lifo = Developer.new(name: "lifo")
       assert_raises(ActiveRecord::RecordInvalid) { firm.developers << lifo }
 
-      lifo = Developer.create!(:name => 'lifo')
+      lifo = Developer.create!(name: "lifo")
       assert_raises(ActiveRecord::RecordInvalid) { firm.developers << lifo }
     end
   end
@@ -694,7 +692,7 @@ class HasManyThroughAssociationsTest < ActiveRecord::TestCase
       [:added, :after, "Michael"]
     ], log.last(2)
 
-    post.people_with_callbacks.push(people(:david), Person.create!(:first_name => "Bob"), Person.new(:first_name => "Lary"))
+    post.people_with_callbacks.push(people(:david), Person.create!(first_name: "Bob"), Person.new(first_name: "Lary"))
     assert_equal [
       [:added, :before, "David"],
       [:added, :after, "David"],
@@ -702,21 +700,21 @@ class HasManyThroughAssociationsTest < ActiveRecord::TestCase
       [:added, :after, "Bob"],
       [:added, :before, "Lary"],
       [:added, :after, "Lary"]
-    ],log.last(6)
+    ], log.last(6)
 
-    post.people_with_callbacks.build(:first_name => "Ted")
+    post.people_with_callbacks.build(first_name: "Ted")
     assert_equal [
       [:added, :before, "Ted"],
       [:added, :after, "Ted"]
     ], log.last(2)
 
-    post.people_with_callbacks.create(:first_name => "Sam")
+    post.people_with_callbacks.create(first_name: "Sam")
     assert_equal [
       [:added, :before, "Sam"],
       [:added, :after, "Sam"]
     ], log.last(2)
 
-    post.people_with_callbacks = [people(:michael),people(:david), Person.new(:first_name => "Julian"), Person.create!(:first_name => "Roger")]
+    post.people_with_callbacks = [people(:michael), people(:david), Person.new(first_name: "Julian"), Person.create!(first_name: "Roger")]
     assert_equal((%w(Ted Bob Sam Lary) * 2).sort, log[-12..-5].collect(&:last).sort)
     assert_equal [
       [:added, :before, "Julian"],
@@ -729,7 +727,7 @@ class HasManyThroughAssociationsTest < ActiveRecord::TestCase
   def test_dynamic_find_should_respect_association_include
     # SQL error in sort clause if :include is not included
     # due to Unknown column 'comments.id'
-    assert Person.find(1).posts_with_comments_sorted_by_comment_id.find_by_title('Welcome to the weblog')
+    assert Person.find(1).posts_with_comments_sorted_by_comment_id.find_by_title("Welcome to the weblog")
   end
 
   def test_count_with_include_should_alias_join_table
@@ -745,7 +743,7 @@ class HasManyThroughAssociationsTest < ActiveRecord::TestCase
   end
 
   def test_get_ids_for_has_many_through_with_conditions_should_not_preload
-    Tagging.create!(:taggable_type => 'Post', :taggable_id => posts(:welcome).id, :tag => tags(:misc))
+    Tagging.create!(taggable_type: "Post", taggable_id: posts(:welcome).id, tag: tags(:misc))
     assert_not_called(ActiveRecord::Associations::Preloader, :new) do
       posts(:welcome).misc_tag_ids
     end
@@ -776,16 +774,16 @@ class HasManyThroughAssociationsTest < ActiveRecord::TestCase
   end
 
   def test_has_many_association_through_a_belongs_to_association_where_the_association_doesnt_exist
-    post = Post.create!(:title => "TITLE", :body => "BODY")
+    post = Post.create!(title: "TITLE", body: "BODY")
     assert_equal [], post.author_favorites
   end
 
   def test_has_many_association_through_a_belongs_to_association
     author = authors(:mary)
-    post = Post.create!(:author => author, :title => "TITLE", :body => "BODY")
-    author.author_favorites.create(:favorite_author_id => 1)
-    author.author_favorites.create(:favorite_author_id => 2)
-    author.author_favorites.create(:favorite_author_id => 3)
+    post = Post.create!(author: author, title: "TITLE", body: "BODY")
+    author.author_favorites.create(favorite_author_id: 1)
+    author.author_favorites.create(favorite_author_id: 2)
+    author.author_favorites.create(favorite_author_id: 3)
     assert_equal post.author.author_favorites, post.author_favorites
   end
 
@@ -809,37 +807,37 @@ class HasManyThroughAssociationsTest < ActiveRecord::TestCase
 
   def test_modifying_has_many_through_has_one_reflection_should_raise
     [
-      lambda { authors(:david).very_special_comments = [VerySpecialComment.create!(:body => "Gorp!", :post_id => 1011), VerySpecialComment.create!(:body => "Eep!", :post_id => 1012)] },
-      lambda { authors(:david).very_special_comments << VerySpecialComment.create!(:body => "Hoohah!", :post_id => 1013) },
+      lambda { authors(:david).very_special_comments = [VerySpecialComment.create!(body: "Gorp!", post_id: 1011), VerySpecialComment.create!(body: "Eep!", post_id: 1012)] },
+      lambda { authors(:david).very_special_comments << VerySpecialComment.create!(body: "Hoohah!", post_id: 1013) },
       lambda { authors(:david).very_special_comments.delete(authors(:david).very_special_comments.first) },
-    ].each {|block| assert_raise(ActiveRecord::HasManyThroughCantAssociateThroughHasOneOrManyReflection, &block) }
+    ].each { |block| assert_raise(ActiveRecord::HasManyThroughCantAssociateThroughHasOneOrManyReflection, &block) }
   end
 
   def test_has_many_association_through_a_has_many_association_to_self
-    sarah = Person.create!(:first_name => 'Sarah', :primary_contact_id => people(:susan).id, :gender => 'F', :number1_fan_id => 1)
-    john = Person.create!(:first_name => 'John', :primary_contact_id => sarah.id, :gender => 'M', :number1_fan_id => 1)
+    sarah = Person.create!(first_name: "Sarah", primary_contact_id: people(:susan).id, gender: "F", number1_fan_id: 1)
+    john = Person.create!(first_name: "John", primary_contact_id: sarah.id, gender: "M", number1_fan_id: 1)
     assert_equal sarah.agents, [john]
-    assert_equal people(:susan).agents.flat_map(&:agents), people(:susan).agents_of_agents
+    assert_equal people(:susan).agents.flat_map(&:agents).sort, people(:susan).agents_of_agents.sort
   end
 
   def test_associate_existing_with_nonstandard_primary_key_on_belongs_to
-    Categorization.create(:author => authors(:mary), :named_category_name => categories(:general).name)
+    Categorization.create(author: authors(:mary), named_category_name: categories(:general).name)
     assert_equal categories(:general), authors(:mary).named_categories.first
   end
 
   def test_collection_build_with_nonstandard_primary_key_on_belongs_to
     author   = authors(:mary)
-    category = author.named_categories.build(:name => "Primary")
+    category = author.named_categories.build(name: "Primary")
     author.save
-    assert Categorization.exists?(:author_id => author.id, :named_category_name => category.name)
-    assert author.named_categories.reload.include?(category)
+    assert Categorization.exists?(author_id: author.id, named_category_name: category.name)
+    assert_includes author.named_categories.reload, category
   end
 
   def test_collection_create_with_nonstandard_primary_key_on_belongs_to
     author   = authors(:mary)
-    category = author.named_categories.create(:name => "Primary")
-    assert Categorization.exists?(:author_id => author.id, :named_category_name => category.name)
-    assert author.named_categories.reload.include?(category)
+    category = author.named_categories.create(name: "Primary")
+    assert Categorization.exists?(author_id: author.id, named_category_name: category.name)
+    assert_includes author.named_categories.reload, category
   end
 
   def test_collection_exists
@@ -851,9 +849,9 @@ class HasManyThroughAssociationsTest < ActiveRecord::TestCase
 
   def test_collection_delete_with_nonstandard_primary_key_on_belongs_to
     author   = authors(:mary)
-    category = author.named_categories.create(:name => "Primary")
+    category = author.named_categories.create(name: "Primary")
     author.named_categories.delete(category)
-    assert !Categorization.exists?(:author_id => author.id, :named_category_name => category.name)
+    assert !Categorization.exists?(author_id: author.id, named_category_name: category.name)
     assert author.named_categories.reload.empty?
   end
 
@@ -871,6 +869,14 @@ class HasManyThroughAssociationsTest < ActiveRecord::TestCase
     assert_equal [dev], company.developers
   end
 
+  def test_collection_singular_ids_setter_with_required_type_cast
+    company = companies(:rails_core)
+    dev = Developer.first
+
+    company.developer_ids = [dev.id.to_s]
+    assert_equal [dev], company.developers
+  end
+
   def test_collection_singular_ids_setter_with_string_primary_keys
     assert_nothing_raised do
       book = books(:awdr)
@@ -880,26 +886,35 @@ class HasManyThroughAssociationsTest < ActiveRecord::TestCase
       book.subscriber_ids = []
       assert_equal [], book.subscribers.reload
     end
-
   end
 
   def test_collection_singular_ids_setter_raises_exception_when_invalid_ids_set
     company = companies(:rails_core)
-    ids =  [Developer.first.id, -9999]
-    assert_raises(ActiveRecord::AssociationTypeMismatch) {company.developer_ids= ids}
+    ids = [Developer.first.id, -9999]
+    e = assert_raises(ActiveRecord::RecordNotFound) { company.developer_ids = ids }
+    msg = "Couldn't find all Developers with 'id': (1, -9999) (found 1 results, but was looking for 2). Couldn't find Developer with id -9999."
+    assert_equal(msg, e.message)
+  end
+
+  def test_collection_singular_ids_through_setter_raises_exception_when_invalid_ids_set
+    author = authors(:david)
+    ids = [categories(:general).name, "Unknown"]
+    e = assert_raises(ActiveRecord::RecordNotFound) { author.essay_category_ids = ids }
+    msg = "Couldn't find all Categories with 'name': (General, Unknown) (found 1 results, but was looking for 2). Couldn't find Category with name Unknown."
+    assert_equal msg, e.message
   end
 
   def test_build_a_model_from_hm_through_association_with_where_clause
-    assert_nothing_raised { books(:awdr).subscribers.where(:nick => "marklazz").build }
+    assert_nothing_raised { books(:awdr).subscribers.where(nick: "marklazz").build }
   end
 
   def test_attributes_are_being_set_when_initialized_from_hm_through_association_with_where_clause
-    new_subscriber = books(:awdr).subscribers.where(:nick => "marklazz").build
+    new_subscriber = books(:awdr).subscribers.where(nick: "marklazz").build
     assert_equal new_subscriber.nick, "marklazz"
   end
 
   def test_attributes_are_being_set_when_initialized_from_hm_through_association_with_multiple_where_clauses
-    new_subscriber = books(:awdr).subscribers.where(:nick => "marklazz").where(:name => 'Marcelo Giorgi').build
+    new_subscriber = books(:awdr).subscribers.where(nick: "marklazz").where(name: "Marcelo Giorgi").build
     assert_equal new_subscriber.nick, "marklazz"
     assert_equal new_subscriber.name, "Marcelo Giorgi"
   end
@@ -908,14 +923,14 @@ class HasManyThroughAssociationsTest < ActiveRecord::TestCase
     person = Person.new
     reference = person.references.build
     job = reference.build_job
-    assert person.jobs.include?(job)
+    assert_includes person.jobs, job
   end
 
   def test_include_method_in_association_through_should_return_true_for_instance_added_with_nested_builds
     author = Author.new
     post = author.posts.build
     comment = post.comments.build
-    assert author.comments.include?(comment)
+    assert_includes author.comments, comment
   end
 
   def test_through_association_readonly_should_be_false
@@ -929,10 +944,17 @@ class HasManyThroughAssociationsTest < ActiveRecord::TestCase
     end
   end
 
+  def test_has_many_through_polymorphic_with_rewhere
+    post = TaggedPost.create!(title: "Tagged", body: "Post")
+    tag = post.tags.create!(name: "Tag")
+    assert_equal [tag], TaggedPost.preload(:tags).last.tags
+    assert_equal [tag], TaggedPost.eager_load(:tags).last.tags
+  end
+
   def test_has_many_through_polymorphic_with_primary_key_option
     assert_equal [categories(:general)], authors(:david).essay_categories
 
-    authors = Author.joins(:essay_categories).where('categories.id' => categories(:general).id)
+    authors = Author.joins(:essay_categories).where("categories.id" => categories(:general).id)
     assert_equal authors(:david), authors.first
 
     assert_equal [owners(:blackbeard)], authors(:david).essay_owners
@@ -944,7 +966,7 @@ class HasManyThroughAssociationsTest < ActiveRecord::TestCase
   def test_has_many_through_with_primary_key_option
     assert_equal [categories(:general)], authors(:david).essay_categories_2
 
-    authors = Author.joins(:essay_categories_2).where('categories.id' => categories(:general).id)
+    authors = Author.joins(:essay_categories_2).where("categories.id" => categories(:general).id)
     assert_equal authors(:david), authors.first
   end
 
@@ -956,30 +978,30 @@ class HasManyThroughAssociationsTest < ActiveRecord::TestCase
   end
 
   def test_has_many_through_with_default_scope_on_join_model
-    assert_equal posts(:welcome).comments.order('id').to_a, authors(:david).comments_on_first_posts
+    assert_equal posts(:welcome).comments.order("id").to_a, authors(:david).comments_on_first_posts
   end
 
   def test_create_has_many_through_with_default_scope_on_join_model
-    category = authors(:david).special_categories.create(:name => "Foo")
-    assert_equal 1, category.categorizations.where(:special => true).count
+    category = authors(:david).special_categories.create(name: "Foo")
+    assert_equal 1, category.categorizations.where(special: true).count
   end
 
   def test_joining_has_many_through_with_distinct
-    mary = Author.joins(:unique_categorized_posts).where(:id => authors(:mary).id).first
+    mary = Author.joins(:unique_categorized_posts).where(id: authors(:mary).id).first
     assert_equal 1, mary.unique_categorized_posts.length
     assert_equal 1, mary.unique_categorized_post_ids.length
   end
 
   def test_joining_has_many_through_belongs_to
-    posts = Post.joins(:author_categorizations).order('posts.id').
-                 where('categorizations.id' => categorizations(:mary_thinking_sti).id)
+    posts = Post.joins(:author_categorizations).order("posts.id").
+                 where("categorizations.id" => categorizations(:mary_thinking_sti).id)
 
     assert_equal [posts(:eager_other), posts(:misc_by_mary), posts(:other_by_mary)], posts
   end
 
   def test_select_chosen_fields_only
     author = authors(:david)
-    assert_equal ['body', 'id'].sort, author.comments.select('comments.body').first.attributes.keys.sort
+    assert_equal ["body", "id"].sort, author.comments.select("comments.body").first.attributes.keys.sort
   end
 
   def test_get_has_many_through_belongs_to_ids_with_conditions
@@ -1022,7 +1044,7 @@ class HasManyThroughAssociationsTest < ActiveRecord::TestCase
     post    = posts(:welcome)
     address = author_addresses(:david_address)
 
-    assert post.author_addresses.include?(address)
+    assert_includes post.author_addresses, address
     post.author_addresses.delete(address)
     assert post[:author_count].nil?
   end
@@ -1030,7 +1052,7 @@ class HasManyThroughAssociationsTest < ActiveRecord::TestCase
   def test_primary_key_option_on_source
     post     = posts(:welcome)
     category = categories(:general)
-    Categorization.create!(:post_id => post.id, :named_category_name => category.name)
+    Categorization.create!(post_id: post.id, named_category_name: category.name)
 
     assert_equal [category], post.named_categories
     assert_equal [category.name], post.named_category_ids # checks when target loaded
@@ -1039,29 +1061,29 @@ class HasManyThroughAssociationsTest < ActiveRecord::TestCase
 
   def test_create_should_not_raise_exception_when_join_record_has_errors
     repair_validations(Categorization) do
-      Categorization.validate { |r| r.errors[:base] << 'Invalid Categorization' }
-      Category.create(:name => 'Fishing', :authors => [Author.first])
+      Categorization.validate { |r| r.errors[:base] << "Invalid Categorization" }
+      Category.create(name: "Fishing", authors: [Author.first])
     end
   end
 
   def test_assign_array_to_new_record_builds_join_records
-    c = Category.new(:name => 'Fishing', :authors => [Author.first])
+    c = Category.new(name: "Fishing", authors: [Author.first])
     assert_equal 1, c.categorizations.size
   end
 
   def test_create_bang_should_raise_exception_when_join_record_has_errors
     repair_validations(Categorization) do
-      Categorization.validate { |r| r.errors[:base] << 'Invalid Categorization' }
+      Categorization.validate { |r| r.errors[:base] << "Invalid Categorization" }
       assert_raises(ActiveRecord::RecordInvalid) do
-        Category.create!(:name => 'Fishing', :authors => [Author.first])
+        Category.create!(name: "Fishing", authors: [Author.first])
       end
     end
   end
 
   def test_save_bang_should_raise_exception_when_join_record_has_errors
     repair_validations(Categorization) do
-      Categorization.validate { |r| r.errors[:base] << 'Invalid Categorization' }
-      c = Category.new(:name => 'Fishing', :authors => [Author.first])
+      Categorization.validate { |r| r.errors[:base] << "Invalid Categorization" }
+      c = Category.new(name: "Fishing", authors: [Author.first])
       assert_raises(ActiveRecord::RecordInvalid) do
         c.save!
       end
@@ -1070,17 +1092,17 @@ class HasManyThroughAssociationsTest < ActiveRecord::TestCase
 
   def test_save_returns_falsy_when_join_record_has_errors
     repair_validations(Categorization) do
-      Categorization.validate { |r| r.errors[:base] << 'Invalid Categorization' }
-      c = Category.new(:name => 'Fishing', :authors => [Author.first])
+      Categorization.validate { |r| r.errors[:base] << "Invalid Categorization" }
+      c = Category.new(name: "Fishing", authors: [Author.first])
       assert_not c.save
     end
   end
 
   def test_preloading_empty_through_association_via_joins
-    person = Person.create!(:first_name => "Gaga")
-    person = Person.where(:id => person.id).where('readers.id = 1 or 1=1').references(:readers).includes(:posts).to_a.first
+    person = Person.create!(first_name: "Gaga")
+    person = Person.where(id: person.id).where("readers.id = 1 or 1=1").references(:readers).includes(:posts).to_a.first
 
-    assert person.posts.loaded?, 'person.posts should be loaded'
+    assert person.posts.loaded?, "person.posts should be loaded"
     assert_equal [], person.posts
   end
 
@@ -1101,22 +1123,48 @@ class HasManyThroughAssociationsTest < ActiveRecord::TestCase
   end
 
   def test_has_many_through_with_polymorphic_source
-    post = tags(:general).tagged_posts.create! :title => "foo", :body => "bar"
+    post = tags(:general).tagged_posts.create! title: "foo", body: "bar"
     assert_equal [tags(:general)], post.reload.tags
   end
 
   def test_has_many_through_obeys_order_on_through_association
     owner = owners(:blackbeard)
-    assert owner.toys.to_sql.include?("pets.name desc")
+    assert_includes owner.toys.to_sql, "pets.name desc"
     assert_equal ["parrot", "bulbul"], owner.toys.map { |r| r.pet.name }
   end
 
+  def test_has_many_through_associations_sum_on_columns
+    post1 = Post.create(title: "active", body: "sample")
+    post2 = Post.create(title: "inactive", body: "sample")
+
+    person1 = Person.create(first_name: "aaron", followers_count: 1)
+    person2 = Person.create(first_name: "schmit", followers_count: 2)
+    person3 = Person.create(first_name: "bill", followers_count: 3)
+    person4 = Person.create(first_name: "cal", followers_count: 4)
+
+    Reader.create(post_id: post1.id, person_id: person1.id)
+    Reader.create(post_id: post1.id, person_id: person2.id)
+    Reader.create(post_id: post1.id, person_id: person3.id)
+    Reader.create(post_id: post1.id, person_id: person4.id)
+
+    Reader.create(post_id: post2.id, person_id: person1.id)
+    Reader.create(post_id: post2.id, person_id: person2.id)
+    Reader.create(post_id: post2.id, person_id: person3.id)
+    Reader.create(post_id: post2.id, person_id: person4.id)
+
+    active_persons = Person.joins(:readers).joins(:posts).distinct(true).where("posts.title" => "active")
+
+    assert_equal active_persons.map(&:followers_count).reduce(:+), 10
+    assert_equal active_persons.sum(:followers_count), 10
+    assert_equal active_persons.sum(:followers_count), active_persons.map(&:followers_count).reduce(:+)
+  end
+
   def test_has_many_through_associations_on_new_records_use_null_relations
     person = Person.new
 
     assert_no_queries(ignore_none: false) do
       assert_equal [], person.posts
-      assert_equal [], person.posts.where(body: 'omg')
+      assert_equal [], person.posts.where(body: "omg")
       assert_equal [], person.posts.pluck(:body)
       assert_equal 0,  person.posts.sum(:tags_count)
       assert_equal 0,  person.posts.count
@@ -1148,9 +1196,9 @@ class HasManyThroughAssociationsTest < ActiveRecord::TestCase
   end
 
   def test_has_many_through_unscope_default_scope
-    post = Post.create!(:title => 'Beaches', :body => "I like beaches!")
-    Reader.create! :person => people(:david), :post => post
-    LazyReader.create! :person => people(:susan), :post => post
+    post = Post.create!(title: "Beaches", body: "I like beaches!")
+    Reader.create! person: people(:david), post: post
+    LazyReader.create! person: people(:susan), post: post
 
     assert_equal 2, post.people.to_a.size
     assert_equal 1, post.lazy_people.to_a.size
@@ -1160,8 +1208,8 @@ class HasManyThroughAssociationsTest < ActiveRecord::TestCase
   end
 
   def test_has_many_through_add_with_sti_middle_relation
-    club = SuperClub.create!(name: 'Fight Club')
-    member = Member.create!(name: 'Tyler Durden')
+    club = SuperClub.create!(name: "Fight Club")
+    member = Member.create!(name: "Tyler Durden")
 
     club.members << member
     assert_equal 1, SuperMembership.where(member_id: member.id, club_id: club.id).count
@@ -1182,12 +1230,6 @@ class HasManyThroughAssociationsTest < ActiveRecord::TestCase
     assert_nil Club.new.special_favourites.distinct_value
   end
 
-  def test_association_force_reload_with_only_true_is_deprecated
-    post = Post.find(1)
-
-    assert_deprecated { post.people(true) }
-  end
-
   def test_has_many_through_do_not_cache_association_reader_if_the_though_method_has_default_scopes
     member = Member.create!
     club = Club.create!
@@ -1215,4 +1257,73 @@ class HasManyThroughAssociationsTest < ActiveRecord::TestCase
   ensure
     TenantMembership.current_member = nil
   end
+
+  def test_has_many_through_with_scope_that_has_joined_same_table_with_parent_relation
+    assert_equal authors(:david), Author.joins(:comments_for_first_author).take
+  end
+
+  def test_has_many_through_with_unscope_should_affect_to_through_scope
+    assert_equal [comments(:eager_other_comment1)], authors(:mary).unordered_comments
+  end
+
+  def test_has_many_through_with_scope_should_accept_string_and_hash_join
+    assert_equal authors(:david), Author.joins({ comments_for_first_author: :post }, "inner join posts posts_alias on authors.id = posts_alias.author_id").eager_load(:categories).take
+  end
+
+  def test_has_many_through_with_scope_should_respect_table_alias
+    family = Family.create!
+    users = 3.times.map { User.create! }
+    FamilyTree.create!(member: users[0], family: family)
+    FamilyTree.create!(member: users[1], family: family)
+    FamilyTree.create!(member: users[2], family: family, token: "wat")
+
+    assert_equal 2, users[0].family_members.to_a.size
+    assert_equal 0, users[2].family_members.to_a.size
+  end
+
+  def test_through_scope_is_affected_by_unscoping
+    author = authors(:david)
+
+    expected = author.comments.to_a
+    FirstPost.unscoped do
+      assert_equal expected.sort_by(&:id), author.comments_on_first_posts.sort_by(&:id)
+    end
+  end
+
+  def test_through_scope_isnt_affected_by_scoping
+    author = authors(:david)
+
+    expected = author.comments_on_first_posts.to_a
+    FirstPost.where(id: 2).scoping do
+      author.comments_on_first_posts.reset
+      assert_equal expected.sort_by(&:id), author.comments_on_first_posts.sort_by(&:id)
+    end
+  end
+
+  def test_incorrectly_ordered_through_associations
+    assert_raises(ActiveRecord::HasManyThroughOrderError) do
+      DeveloperWithIncorrectlyOrderedHasManyThrough.create(
+        companies: [Company.create]
+      )
+    end
+  end
+
+  private
+    def make_model(name)
+      Class.new(ActiveRecord::Base) { define_singleton_method(:name) { name } }
+    end
+
+    def make_no_pk_hm_t
+      lesson = make_model "Lesson"
+      student = make_model "Student"
+
+      lesson_student = make_model "LessonStudent"
+      lesson_student.table_name = "lessons_students"
+
+      lesson_student.belongs_to :lesson, anonymous_class: lesson
+      lesson_student.belongs_to :student, anonymous_class: student
+      lesson.has_many :lesson_students, anonymous_class: lesson_student
+      lesson.has_many :students, through: :lesson_students, anonymous_class: student
+      [lesson, lesson_student, student]
+    end
 end
diff --git a/activerecord/test/cases/associations/has_one_associations_test.rb b/activerecord/test/cases/associations/has_one_associations_test.rb
index 1574f373c2..ec5d95080b 100644
--- a/activerecord/test/cases/associations/has_one_associations_test.rb
+++ b/activerecord/test/cases/associations/has_one_associations_test.rb
@@ -1,19 +1,21 @@
+# frozen_string_literal: true
+
 require "cases/helper"
-require 'models/developer'
-require 'models/computer'
-require 'models/project'
-require 'models/company'
-require 'models/ship'
-require 'models/pirate'
-require 'models/car'
-require 'models/bulb'
-require 'models/author'
-require 'models/image'
-require 'models/post'
+require "models/developer"
+require "models/computer"
+require "models/project"
+require "models/company"
+require "models/ship"
+require "models/pirate"
+require "models/car"
+require "models/bulb"
+require "models/author"
+require "models/image"
+require "models/post"
 
 class HasOneAssociationsTest < ActiveRecord::TestCase
   self.use_transactional_tests = false unless supports_savepoints?
-  fixtures :accounts, :companies, :developers, :projects, :developers_projects, :ships, :pirates
+  fixtures :accounts, :companies, :developers, :projects, :developers_projects, :ships, :pirates, :authors, :author_addresses
 
   def setup
     Account.destroyed_account_ids.clear
@@ -28,7 +30,8 @@ class HasOneAssociationsTest < ActiveRecord::TestCase
     ActiveRecord::SQLCounter.clear_log
     companies(:first_firm).account
   ensure
-    assert ActiveRecord::SQLCounter.log_all.all? { |sql| /order by/i !~ sql }, 'ORDER BY was used in the query'
+    log_all = ActiveRecord::SQLCounter.log_all
+    assert log_all.all? { |sql| /order by/i !~ sql }, "ORDER BY was used in the query: #{log_all}"
   end
 
   def test_has_one_cache_nils
@@ -36,13 +39,13 @@ class HasOneAssociationsTest < ActiveRecord::TestCase
     assert_queries(1) { assert_nil firm.account }
     assert_queries(0) { assert_nil firm.account }
 
-    firms = Firm.all.merge!(:includes => :account).to_a
+    firms = Firm.all.merge!(includes: :account).to_a
     assert_queries(0) { firms.each(&:account) }
   end
 
   def test_with_select
     assert_equal Firm.find(1).account_with_select.attributes.size, 2
-    assert_equal Firm.all.merge!(:includes => :account_with_select).find(1).account_with_select.attributes.size, 2
+    assert_equal Firm.all.merge!(includes: :account_with_select).find(1).account_with_select.attributes.size, 2
   end
 
   def test_finding_using_primary_key
@@ -102,7 +105,7 @@ class HasOneAssociationsTest < ActiveRecord::TestCase
   def test_nullification_on_association_change
     firm = companies(:rails_core)
     old_account_id = firm.account.id
-    firm.account = Account.new(:credit_limit => 5)
+    firm.account = Account.new(credit_limit: 5)
     # account is dependent with nullify, therefore its firm_id should be nil
     assert_nil Account.find(old_account_id).firm_id
   end
@@ -125,12 +128,12 @@ class HasOneAssociationsTest < ActiveRecord::TestCase
   end
 
   def test_association_change_calls_delete
-    companies(:first_firm).deletable_account = Account.new(:credit_limit => 5)
+    companies(:first_firm).deletable_account = Account.new(credit_limit: 5)
     assert_equal [], Account.destroyed_account_ids[companies(:first_firm).id]
   end
 
   def test_association_change_calls_destroy
-    companies(:first_firm).account = Account.new(:credit_limit => 5)
+    companies(:first_firm).account = Account.new(credit_limit: 5)
     assert_equal [companies(:first_firm).id], Account.destroyed_account_ids[companies(:first_firm).id]
   end
 
@@ -170,44 +173,25 @@ class HasOneAssociationsTest < ActiveRecord::TestCase
   end
 
   def test_dependence_with_nil_associate
-    firm = DependentFirm.new(:name => 'nullify')
+    firm = DependentFirm.new(name: "nullify")
     firm.save!
     assert_nothing_raised { firm.destroy }
   end
 
   def test_restrict_with_exception
-    firm = RestrictedWithExceptionFirm.create!(:name => 'restrict')
-    firm.create_account(:credit_limit => 10)
-
-    assert_not_nil firm.account
-
-    assert_raise(ActiveRecord::DeleteRestrictionError) { firm.destroy }
-    assert RestrictedWithExceptionFirm.exists?(:name => 'restrict')
-    assert firm.account.present?
-  end
-
-  def test_restrict_with_error_is_deprecated_using_key_one
-    I18n.backend = I18n::Backend::Simple.new
-    I18n.backend.store_translations :en, activerecord: { errors: { messages: { restrict_dependent_destroy: { one: 'message for deprecated key' } } } }
-
-    firm = RestrictedWithErrorFirm.create!(name: 'restrict')
+    firm = RestrictedWithExceptionFirm.create!(name: "restrict")
     firm.create_account(credit_limit: 10)
 
     assert_not_nil firm.account
 
-    assert_deprecated { firm.destroy }
-
-    assert !firm.errors.empty?
-    assert_equal 'message for deprecated key', firm.errors[:base].first
-    assert RestrictedWithErrorFirm.exists?(name: 'restrict')
+    assert_raise(ActiveRecord::DeleteRestrictionError) { firm.destroy }
+    assert RestrictedWithExceptionFirm.exists?(name: "restrict")
     assert firm.account.present?
-  ensure
-    I18n.backend.reload!
   end
 
   def test_restrict_with_error
-    firm = RestrictedWithErrorFirm.create!(:name => 'restrict')
-    firm.create_account(:credit_limit => 10)
+    firm = RestrictedWithErrorFirm.create!(name: "restrict")
+    firm.create_account(credit_limit: 10)
 
     assert_not_nil firm.account
 
@@ -215,14 +199,14 @@ class HasOneAssociationsTest < ActiveRecord::TestCase
 
     assert !firm.errors.empty?
     assert_equal "Cannot delete record because a dependent account exists", firm.errors[:base].first
-    assert RestrictedWithErrorFirm.exists?(:name => 'restrict')
+    assert RestrictedWithErrorFirm.exists?(name: "restrict")
     assert firm.account.present?
   end
 
   def test_restrict_with_error_with_locale
     I18n.backend = I18n::Backend::Simple.new
-    I18n.backend.store_translations 'en', activerecord: {attributes: {restricted_with_error_firm: {account: 'firm account'}}}
-    firm = RestrictedWithErrorFirm.create!(name: 'restrict')
+    I18n.backend.store_translations "en", activerecord: { attributes: { restricted_with_error_firm: { account: "firm account" } } }
+    firm = RestrictedWithErrorFirm.create!(name: "restrict")
     firm.create_account(credit_limit: 10)
 
     assert_not_nil firm.account
@@ -231,7 +215,7 @@ class HasOneAssociationsTest < ActiveRecord::TestCase
 
     assert !firm.errors.empty?
     assert_equal "Cannot delete record because a dependent firm account exists", firm.errors[:base].first
-    assert RestrictedWithErrorFirm.exists?(name: 'restrict')
+    assert RestrictedWithErrorFirm.exists?(name: "restrict")
     assert firm.account.present?
   ensure
     I18n.backend.reload!
@@ -260,24 +244,24 @@ class HasOneAssociationsTest < ActiveRecord::TestCase
 
   def test_building_the_associated_object_with_explicit_sti_base_class
     firm = DependentFirm.new
-    company = firm.build_company(:type => "Company")
+    company = firm.build_company(type: "Company")
     assert_kind_of Company, company, "Expected #{company.class} to be a Company"
   end
 
   def test_building_the_associated_object_with_sti_subclass
     firm = DependentFirm.new
-    company = firm.build_company(:type => "Client")
+    company = firm.build_company(type: "Client")
     assert_kind_of Client, company, "Expected #{company.class} to be a Client"
   end
 
   def test_building_the_associated_object_with_an_invalid_type
     firm = DependentFirm.new
-    assert_raise(ActiveRecord::SubclassNotFound) { firm.build_company(:type => "Invalid") }
+    assert_raise(ActiveRecord::SubclassNotFound) { firm.build_company(type: "Invalid") }
   end
 
   def test_building_the_associated_object_with_an_unrelated_type
     firm = DependentFirm.new
-    assert_raise(ActiveRecord::SubclassNotFound) { firm.build_company(:type => "Account") }
+    assert_raise(ActiveRecord::SubclassNotFound) { firm.build_company(type: "Account") }
   end
 
   def test_build_and_create_should_not_happen_within_scope
@@ -295,19 +279,19 @@ class HasOneAssociationsTest < ActiveRecord::TestCase
   end
 
   def test_create_association
-    firm = Firm.create(:name => "GlobalMegaCorp")
-    account = firm.create_account(:credit_limit => 1000)
+    firm = Firm.create(name: "GlobalMegaCorp")
+    account = firm.create_account(credit_limit: 1000)
     assert_equal account, firm.reload.account
   end
 
   def test_create_association_with_bang
-    firm = Firm.create(:name => "GlobalMegaCorp")
-    account = firm.create_account!(:credit_limit => 1000)
+    firm = Firm.create(name: "GlobalMegaCorp")
+    account = firm.create_account!(credit_limit: 1000)
     assert_equal account, firm.reload.account
   end
 
   def test_create_association_with_bang_failing
-    firm = Firm.create(:name => "GlobalMegaCorp")
+    firm = Firm.create(name: "GlobalMegaCorp")
     assert_raise ActiveRecord::RecordInvalid do
       firm.create_account!
     end
@@ -319,13 +303,32 @@ class HasOneAssociationsTest < ActiveRecord::TestCase
   end
 
   def test_create_with_inexistent_foreign_key_failing
-    firm = Firm.create(name: 'GlobalMegaCorp')
+    firm = Firm.create(name: "GlobalMegaCorp")
 
     assert_raises(ActiveRecord::UnknownAttributeError) do
       firm.create_account_with_inexistent_foreign_key
     end
   end
 
+  def test_create_when_parent_is_new_raises
+    firm = Firm.new
+    error = assert_raise(ActiveRecord::RecordNotSaved) do
+      firm.create_account
+    end
+
+    assert_equal "You cannot call create unless the parent is saved", error.message
+  end
+
+  def test_reload_association
+    odegy = companies(:odegy)
+
+    assert_equal 53, odegy.account.credit_limit
+    Account.where(id: odegy.account.id).update_all(credit_limit: 80)
+    assert_equal 53, odegy.account.credit_limit
+
+    assert_equal 80, odegy.reload_account.credit_limit
+  end
+
   def test_build
     firm = Firm.new("name" => "GlobalMegaCorp")
     firm.save
@@ -365,7 +368,7 @@ class HasOneAssociationsTest < ActiveRecord::TestCase
 
   def test_finding_with_interpolated_condition
     firm = Firm.first
-    superior = firm.clients.create(:name => 'SuperiorCo')
+    superior = firm.clients.create(name: "SuperiorCo")
     superior.rating = 10
     superior.save
     assert_equal 10, firm.clients_with_interpolated_conditions.first.rating
@@ -382,7 +385,7 @@ class HasOneAssociationsTest < ActiveRecord::TestCase
   end
 
   def test_save_still_works_after_accessing_nil_has_one
-    jp = Company.new :name => 'Jaded Pixel'
+    jp = Company.new name: "Jaded Pixel"
     jp.dummy_account.nil?
 
     assert_nothing_raised do
@@ -411,14 +414,14 @@ class HasOneAssociationsTest < ActiveRecord::TestCase
 
     assert_nothing_raised do
       Firm.find(@firm.id).save!
-      Firm.all.merge!(:includes => :account).find(@firm.id).save!
+      Firm.all.merge!(includes: :account).find(@firm.id).save!
     end
 
     @firm.account.destroy
 
     assert_nothing_raised do
       Firm.find(@firm.id).save!
-      Firm.all.merge!(:includes => :account).find(@firm.id).save!
+      Firm.all.merge!(includes: :account).find(@firm.id).save!
     end
   end
 
@@ -435,7 +438,7 @@ class HasOneAssociationsTest < ActiveRecord::TestCase
   end
 
   def test_attributes_are_being_set_when_initialized_from_has_one_association_with_where_clause
-    new_account = companies(:first_firm).build_account(:firm_name => 'Account')
+    new_account = companies(:first_firm).build_account(firm_name: "Account")
     assert_equal new_account.firm_name, "Account"
   end
 
@@ -485,7 +488,7 @@ class HasOneAssociationsTest < ActiveRecord::TestCase
 
     assert_equal ships(:black_pearl), pirate.ship
     assert_equal pirate.id, pirate.ship.pirate_id
-    assert_equal "Failed to remove the existing associated ship. " +
+    assert_equal "Failed to remove the existing associated ship. " \
                  "The record failed to save after its foreign key was set to nil.", error.message
   end
 
@@ -505,63 +508,63 @@ class HasOneAssociationsTest < ActiveRecord::TestCase
   end
 
   def test_association_keys_bypass_attribute_protection
-    car = Car.create(:name => 'honda')
+    car = Car.create(name: "honda")
 
     bulb = car.build_bulb
     assert_equal car.id, bulb.car_id
 
-    bulb = car.build_bulb :car_id => car.id + 1
+    bulb = car.build_bulb car_id: car.id + 1
     assert_equal car.id, bulb.car_id
 
     bulb = car.create_bulb
     assert_equal car.id, bulb.car_id
 
-    bulb = car.create_bulb :car_id => car.id + 1
+    bulb = car.create_bulb car_id: car.id + 1
     assert_equal car.id, bulb.car_id
   end
 
   def test_association_protect_foreign_key
-    pirate = Pirate.create!(:catchphrase => "Don' botharrr talkin' like one, savvy?")
+    pirate = Pirate.create!(catchphrase: "Don' botharrr talkin' like one, savvy?")
 
     ship = pirate.build_ship
     assert_equal pirate.id, ship.pirate_id
 
-    ship = pirate.build_ship :pirate_id => pirate.id + 1
+    ship = pirate.build_ship pirate_id: pirate.id + 1
     assert_equal pirate.id, ship.pirate_id
 
     ship = pirate.create_ship
     assert_equal pirate.id, ship.pirate_id
 
-    ship = pirate.create_ship :pirate_id => pirate.id + 1
+    ship = pirate.create_ship pirate_id: pirate.id + 1
     assert_equal pirate.id, ship.pirate_id
   end
 
   def test_build_with_block
-    car = Car.create(:name => 'honda')
+    car = Car.create(name: "honda")
 
-    bulb = car.build_bulb{ |b| b.color = 'Red' }
-    assert_equal 'RED!', bulb.color
+    bulb = car.build_bulb { |b| b.color = "Red" }
+    assert_equal "RED!", bulb.color
   end
 
   def test_create_with_block
-    car = Car.create(:name => 'honda')
+    car = Car.create(name: "honda")
 
-    bulb = car.create_bulb{ |b| b.color = 'Red' }
-    assert_equal 'RED!', bulb.color
+    bulb = car.create_bulb { |b| b.color = "Red" }
+    assert_equal "RED!", bulb.color
   end
 
   def test_create_bang_with_block
-    car = Car.create(:name => 'honda')
+    car = Car.create(name: "honda")
 
-    bulb = car.create_bulb!{ |b| b.color = 'Red' }
-    assert_equal 'RED!', bulb.color
+    bulb = car.create_bulb! { |b| b.color = "Red" }
+    assert_equal "RED!", bulb.color
   end
 
   def test_association_attributes_are_available_to_after_initialize
-    car = Car.create(:name => 'honda')
+    car = Car.create(name: "honda")
     bulb = car.create_bulb
 
-    assert_equal car.id, bulb.attributes_after_initialize['car_id']
+    assert_equal car.id, bulb.attributes_after_initialize["car_id"]
   end
 
   def test_has_one_transaction
@@ -581,36 +584,36 @@ class HasOneAssociationsTest < ActiveRecord::TestCase
 
   def test_has_one_assignment_dont_trigger_save_on_change_of_same_object
     pirate = Pirate.create!(catchphrase: "Don' botharrr talkin' like one, savvy?")
-    ship = pirate.build_ship(name: 'old name')
+    ship = pirate.build_ship(name: "old name")
     ship.save!
 
-    ship.name = 'new name'
+    ship.name = "new name"
     assert ship.changed?
     assert_queries(1) do
       # One query for updating name, not triggering query for updating pirate_id
       pirate.ship = ship
     end
 
-    assert_equal 'new name', pirate.ship.reload.name
+    assert_equal "new name", pirate.ship.reload.name
   end
 
   def test_has_one_assignment_triggers_save_on_change_on_replacing_object
     pirate = Pirate.create!(catchphrase: "Don' botharrr talkin' like one, savvy?")
-    ship = pirate.build_ship(name: 'old name')
+    ship = pirate.build_ship(name: "old name")
     ship.save!
 
-    new_ship = Ship.create(name: 'new name')
+    new_ship = Ship.create(name: "new name")
     assert_queries(2) do
-      # One query for updating name and second query for updating pirate_id
+      # One query to nullify the old ship, one query to update the new ship
       pirate.ship = new_ship
     end
 
-    assert_equal 'new name', pirate.ship.reload.name
+    assert_equal "new name", pirate.ship.reload.name
   end
 
   def test_has_one_autosave_with_primary_key_manually_set
-    post = Post.create(id: 1234, title: "Some title", body: 'Some content')
-    author = Author.new(id: 33, name: 'Hank Moody')
+    post = Post.create(id: 1234, title: "Some title", body: "Some content")
+    author = Author.new(id: 33, name: "Hank Moody")
 
     author.post = post
     author.save
@@ -621,7 +624,7 @@ class HasOneAssociationsTest < ActiveRecord::TestCase
   end
 
   def test_has_one_loading_for_new_record
-    post = Post.create!(author_id: 42, title: 'foo', body: 'bar')
+    post = Post.create!(author_id: 42, title: "foo", body: "bar")
     author = Author.new(id: 42)
     assert_equal post, author.post
   end
@@ -635,7 +638,7 @@ class HasOneAssociationsTest < ActiveRecord::TestCase
   end
 
   def test_with_polymorphic_has_one_with_custom_columns_name
-    post = Post.create! :title => 'foo', :body => 'bar'
+    post = Post.create! title: "foo", body: "bar"
     image = Image.create!
 
     post.main_image = image
@@ -644,8 +647,8 @@ class HasOneAssociationsTest < ActiveRecord::TestCase
     assert_equal image, post.main_image
   end
 
-  test 'dangerous association name raises ArgumentError' do
-    [:errors, 'errors', :save, 'save'].each do |name|
+  test "dangerous association name raises ArgumentError" do
+    [:errors, "errors", :save, "save"].each do |name|
       assert_raises(ArgumentError, "Association #{name} should not be allowed") do
         Class.new(ActiveRecord::Base) do
           has_one name
@@ -654,27 +657,72 @@ class HasOneAssociationsTest < ActiveRecord::TestCase
     end
   end
 
-  def test_association_force_reload_with_only_true_is_deprecated
-    firm = Firm.find(1)
+  class SpecialBook < ActiveRecord::Base
+    self.table_name = "books"
+    belongs_to :author, class_name: "SpecialAuthor"
+    has_one :subscription, class_name: "SpecialSupscription", foreign_key: "subscriber_id"
+  end
 
-    assert_deprecated { firm.account(true) }
+  class SpecialAuthor < ActiveRecord::Base
+    self.table_name = "authors"
+    has_one :book, class_name: "SpecialBook", foreign_key: "author_id"
   end
 
-  class SpecialBook < ActiveRecord::Base
-    self.table_name = 'books'
-    belongs_to :author, class_name: 'SpecialAuthor'
+  class SpecialSupscription < ActiveRecord::Base
+    self.table_name = "subscriptions"
+    belongs_to :book, class_name: "SpecialBook"
   end
 
-  class SpecialAuthor < ActiveRecord::Base
-    self.table_name = 'authors'
-    has_one :book, class_name: 'SpecialBook', foreign_key: 'author_id'
+  def test_association_enum_works_properly
+    author = SpecialAuthor.create!(name: "Test")
+    book = SpecialBook.create!(status: "published")
+    author.book = book
+
+    refute_equal 0, SpecialAuthor.joins(:book).where(books: { status: "published" }).count
   end
 
-  def test_assocation_enum_works_properly
-    author = SpecialAuthor.create!(name: 'Test')
-    book = SpecialBook.create!(status: 'published')
+  def test_association_enum_works_properly_with_nested_join
+    author = SpecialAuthor.create!(name: "Test")
+    book = SpecialBook.create!(status: "published")
     author.book = book
 
-    refute_equal 0, SpecialAuthor.joins(:book).where(books: { status: 'published' } ).count
+    where_clause = { books: { subscriptions: { subscriber_id: nil } } }
+    assert_nothing_raised do
+      SpecialAuthor.joins(book: :subscription).where.not(where_clause)
+    end
+  end
+
+  class DestroyByParentBook < ActiveRecord::Base
+    self.table_name = "books"
+    belongs_to :author, class_name: "DestroyByParentAuthor"
+    before_destroy :dont, unless: :destroyed_by_association
+
+    def dont
+      throw(:abort)
+    end
+  end
+
+  class DestroyByParentAuthor < ActiveRecord::Base
+    self.table_name = "authors"
+    has_one :book, class_name: "DestroyByParentBook", foreign_key: "author_id", dependent: :destroy
+  end
+
+  test "destroyed_by_association set in child destroy callback on parent destroy" do
+    author = DestroyByParentAuthor.create!(name: "Test")
+    book = DestroyByParentBook.create!(author: author)
+
+    author.destroy
+
+    assert_not DestroyByParentBook.exists?(book.id)
+  end
+
+  test "destroyed_by_association set in child destroy callback on replace" do
+    author = DestroyByParentAuthor.create!(name: "Test")
+    book = DestroyByParentBook.create!(author: author)
+
+    author.book = DestroyByParentBook.create!
+    author.save!
+
+    assert_not DestroyByParentBook.exists?(book.id)
   end
 end
diff --git a/activerecord/test/cases/associations/has_one_through_associations_test.rb b/activerecord/test/cases/associations/has_one_through_associations_test.rb
index b2b46812b9..1d37457464 100644
--- a/activerecord/test/cases/associations/has_one_through_associations_test.rb
+++ b/activerecord/test/cases/associations/has_one_through_associations_test.rb
@@ -1,29 +1,31 @@
+# frozen_string_literal: true
+
 require "cases/helper"
-require 'models/club'
-require 'models/member_type'
-require 'models/member'
-require 'models/membership'
-require 'models/sponsor'
-require 'models/organization'
-require 'models/member_detail'
-require 'models/minivan'
-require 'models/dashboard'
-require 'models/speedometer'
-require 'models/category'
-require 'models/author'
-require 'models/essay'
-require 'models/owner'
-require 'models/post'
-require 'models/comment'
-require 'models/categorization'
-require 'models/customer'
-require 'models/carrier'
-require 'models/shop_account'
-require 'models/customer_carrier'
+require "models/club"
+require "models/member_type"
+require "models/member"
+require "models/membership"
+require "models/sponsor"
+require "models/organization"
+require "models/member_detail"
+require "models/minivan"
+require "models/dashboard"
+require "models/speedometer"
+require "models/category"
+require "models/author"
+require "models/essay"
+require "models/owner"
+require "models/post"
+require "models/comment"
+require "models/categorization"
+require "models/customer"
+require "models/carrier"
+require "models/shop_account"
+require "models/customer_carrier"
 
 class HasOneThroughAssociationsTest < ActiveRecord::TestCase
   fixtures :member_types, :members, :clubs, :memberships, :sponsors, :organizations, :minivans,
-           :dashboards, :speedometers, :authors, :posts, :comments, :categories, :essays, :owners
+           :dashboards, :speedometers, :authors, :author_addresses, :posts, :comments, :categories, :essays, :owners
 
   def setup
     @member = members(:groucho)
@@ -34,14 +36,14 @@ class HasOneThroughAssociationsTest < ActiveRecord::TestCase
   end
 
   def test_creating_association_creates_through_record
-    new_member = Member.create(:name => "Chris")
-    new_member.club = Club.create(:name => "LRUG")
+    new_member = Member.create(name: "Chris")
+    new_member.club = Club.create(name: "LRUG")
     assert_not_nil new_member.current_membership
     assert_not_nil new_member.club
   end
 
   def test_creating_association_builds_through_record_for_new
-    new_member = Member.new(:name => "Jane")
+    new_member = Member.new(name: "Jane")
     new_member.club = clubs(:moustache_club)
     assert new_member.current_membership
     assert_equal clubs(:moustache_club), new_member.current_membership.club
@@ -51,8 +53,8 @@ class HasOneThroughAssociationsTest < ActiveRecord::TestCase
   end
 
   def test_creating_association_sets_both_parent_ids_for_new
-    member = Member.new(name: 'Sean Griffin')
-    club = Club.new(name: 'Da Club')
+    member = Member.new(name: "Sean Griffin")
+    club = Club.new(name: "Da Club")
 
     member.club = club
 
@@ -65,7 +67,7 @@ class HasOneThroughAssociationsTest < ActiveRecord::TestCase
   end
 
   def test_replace_target_record
-    new_club = Club.create(:name => "Marx Bros")
+    new_club = Club.create(name: "Marx Bros")
     @member.club = new_club
     @member.reload
     assert_equal new_club, @member.club
@@ -73,7 +75,7 @@ class HasOneThroughAssociationsTest < ActiveRecord::TestCase
 
   def test_replacing_target_record_deletes_old_association
     assert_no_difference "Membership.count" do
-      new_club = Club.create(:name => "Bananarama")
+      new_club = Club.create(name: "Bananarama")
       @member.club = new_club
       @member.reload
     end
@@ -82,40 +84,47 @@ class HasOneThroughAssociationsTest < ActiveRecord::TestCase
   def test_set_record_to_nil_should_delete_association
     @member.club = nil
     @member.reload
-    assert_equal nil, @member.current_membership
+    assert_nil @member.current_membership
     assert_nil @member.club
   end
 
+  def test_set_record_after_delete_association
+    @member.club = nil
+    @member.club = clubs(:moustache_club)
+    @member.reload
+    assert_equal clubs(:moustache_club), @member.club
+  end
+
   def test_has_one_through_polymorphic
     assert_equal clubs(:moustache_club), @member.sponsor_club
   end
 
   def test_has_one_through_eager_loading
-    members = assert_queries(3) do #base table, through table, clubs table
-      Member.all.merge!(:includes => :club, :where => ["name = ?", "Groucho Marx"]).to_a
+    members = assert_queries(3) do # base table, through table, clubs table
+      Member.all.merge!(includes: :club, where: ["name = ?", "Groucho Marx"]).to_a
     end
     assert_equal 1, members.size
-    assert_not_nil assert_no_queries {members[0].club}
+    assert_not_nil assert_no_queries { members[0].club }
   end
 
   def test_has_one_through_eager_loading_through_polymorphic
-    members = assert_queries(3) do #base table, through table, clubs table
-      Member.all.merge!(:includes => :sponsor_club, :where => ["name = ?", "Groucho Marx"]).to_a
+    members = assert_queries(3) do # base table, through table, clubs table
+      Member.all.merge!(includes: :sponsor_club, where: ["name = ?", "Groucho Marx"]).to_a
     end
     assert_equal 1, members.size
-    assert_not_nil assert_no_queries {members[0].sponsor_club}
+    assert_not_nil assert_no_queries { members[0].sponsor_club }
   end
 
   def test_has_one_through_with_conditions_eager_loading
     # conditions on the through table
-    assert_equal clubs(:moustache_club), Member.all.merge!(:includes => :favourite_club).find(@member.id).favourite_club
+    assert_equal clubs(:moustache_club), Member.all.merge!(includes: :favourite_club).find(@member.id).favourite_club
     memberships(:membership_of_favourite_club).update_columns(favourite: false)
-    assert_equal nil,                    Member.all.merge!(:includes => :favourite_club).find(@member.id).reload.favourite_club
+    assert_nil Member.all.merge!(includes: :favourite_club).find(@member.id).reload.favourite_club
 
     # conditions on the source table
-    assert_equal clubs(:moustache_club), Member.all.merge!(:includes => :hairy_club).find(@member.id).hairy_club
+    assert_equal clubs(:moustache_club), Member.all.merge!(includes: :hairy_club).find(@member.id).hairy_club
     clubs(:moustache_club).update_columns(name: "Association of Clean-Shaven Persons")
-    assert_equal nil,                    Member.all.merge!(:includes => :hairy_club).find(@member.id).reload.hairy_club
+    assert_nil Member.all.merge!(includes: :hairy_club).find(@member.id).reload.hairy_club
   end
 
   def test_has_one_through_polymorphic_with_source_type
@@ -123,31 +132,31 @@ class HasOneThroughAssociationsTest < ActiveRecord::TestCase
   end
 
   def test_eager_has_one_through_polymorphic_with_source_type
-    clubs = Club.all.merge!(:includes => :sponsored_member, :where => ["name = ?","Moustache and Eyebrow Fancier Club"]).to_a
+    clubs = Club.all.merge!(includes: :sponsored_member, where: ["name = ?", "Moustache and Eyebrow Fancier Club"]).to_a
     # Only the eyebrow fanciers club has a sponsored_member
-    assert_not_nil assert_no_queries {clubs[0].sponsored_member}
+    assert_not_nil assert_no_queries { clubs[0].sponsored_member }
   end
 
   def test_has_one_through_nonpreload_eagerloading
     members = assert_queries(1) do
-      Member.all.merge!(:includes => :club, :where => ["members.name = ?", "Groucho Marx"], :order => 'clubs.name').to_a #force fallback
+      Member.all.merge!(includes: :club, where: ["members.name = ?", "Groucho Marx"], order: "clubs.name").to_a # force fallback
     end
     assert_equal 1, members.size
-    assert_not_nil assert_no_queries {members[0].club}
+    assert_not_nil assert_no_queries { members[0].club }
   end
 
   def test_has_one_through_nonpreload_eager_loading_through_polymorphic
     members = assert_queries(1) do
-      Member.all.merge!(:includes => :sponsor_club, :where => ["members.name = ?", "Groucho Marx"], :order => 'clubs.name').to_a #force fallback
+      Member.all.merge!(includes: :sponsor_club, where: ["members.name = ?", "Groucho Marx"], order: "clubs.name").to_a # force fallback
     end
     assert_equal 1, members.size
-    assert_not_nil assert_no_queries {members[0].sponsor_club}
+    assert_not_nil assert_no_queries { members[0].sponsor_club }
   end
 
   def test_has_one_through_nonpreload_eager_loading_through_polymorphic_with_more_than_one_through_record
-    Sponsor.new(:sponsor_club => clubs(:crazy_club), :sponsorable => members(:groucho)).save!
+    Sponsor.new(sponsor_club: clubs(:crazy_club), sponsorable: members(:groucho)).save!
     members = assert_queries(1) do
-      Member.all.merge!(:includes => :sponsor_club, :where => ["members.name = ?", "Groucho Marx"], :order => 'clubs.name DESC').to_a #force fallback
+      Member.all.merge!(includes: :sponsor_club, where: ["members.name = ?", "Groucho Marx"], order: "clubs.name DESC").to_a # force fallback
     end
     assert_equal 1, members.size
     assert_not_nil assert_no_queries { members[0].sponsor_club }
@@ -159,8 +168,8 @@ class HasOneThroughAssociationsTest < ActiveRecord::TestCase
   end
 
   def test_assigning_association_correctly_assigns_target
-    new_member = Member.create(:name => "Chris")
-    new_member.club = new_club = Club.create(:name => "LRUG")
+    new_member = Member.create(name: "Chris")
+    new_member.club = new_club = Club.create(name: "LRUG")
     assert_equal new_club, new_member.association(:club).target
   end
 
@@ -176,37 +185,37 @@ class HasOneThroughAssociationsTest < ActiveRecord::TestCase
 
   def test_assigning_to_has_one_through_preserves_decorated_join_record
     @organization = organizations(:nsa)
-    assert_difference 'MemberDetail.count', 1 do
-      @member_detail = MemberDetail.new(:extra_data => 'Extra')
+    assert_difference "MemberDetail.count", 1 do
+      @member_detail = MemberDetail.new(extra_data: "Extra")
       @member.member_detail = @member_detail
       @member.organization = @organization
     end
     assert_equal @organization, @member.organization
-    assert @organization.members.include?(@member)
-    assert_equal 'Extra', @member.member_detail.extra_data
+    assert_includes @organization.members, @member
+    assert_equal "Extra", @member.member_detail.extra_data
   end
 
   def test_reassigning_has_one_through
     @organization = organizations(:nsa)
     @new_organization = organizations(:discordians)
 
-    assert_difference 'MemberDetail.count', 1 do
-      @member_detail = MemberDetail.new(:extra_data => 'Extra')
+    assert_difference "MemberDetail.count", 1 do
+      @member_detail = MemberDetail.new(extra_data: "Extra")
       @member.member_detail = @member_detail
       @member.organization = @organization
     end
     assert_equal @organization, @member.organization
-    assert_equal 'Extra', @member.member_detail.extra_data
-    assert @organization.members.include?(@member)
-    assert !@new_organization.members.include?(@member)
+    assert_equal "Extra", @member.member_detail.extra_data
+    assert_includes @organization.members, @member
+    assert_not_includes @new_organization.members, @member
 
-    assert_no_difference 'MemberDetail.count' do
+    assert_no_difference "MemberDetail.count" do
       @member.organization = @new_organization
     end
     assert_equal @new_organization, @member.organization
-    assert_equal 'Extra', @member.member_detail.extra_data
-    assert !@organization.members.include?(@member)
-    assert @new_organization.members.include?(@member)
+    assert_equal "Extra", @member.member_detail.extra_data
+    assert_not_includes @organization.members, @member
+    assert_includes @new_organization.members, @member
   end
 
   def test_preloading_has_one_through_on_belongs_to
@@ -217,7 +226,7 @@ class HasOneThroughAssociationsTest < ActiveRecord::TestCase
     @member.member_detail = @member_detail
     @member.organization = @organization
     @member_details = assert_queries(3) do
-      MemberDetail.all.merge!(:includes => :member_type).to_a
+      MemberDetail.all.merge!(includes: :member_type).to_a
     end
     @new_detail = @member_details[0]
     assert @new_detail.send(:association, :member_type).loaded?
@@ -230,19 +239,19 @@ class HasOneThroughAssociationsTest < ActiveRecord::TestCase
 
     assert_nothing_raised do
       Club.find(@club.id).save!
-      Club.all.merge!(:includes => :sponsored_member).find(@club.id).save!
+      Club.all.merge!(includes: :sponsored_member).find(@club.id).save!
     end
 
     @club.sponsor.destroy
 
     assert_nothing_raised do
       Club.find(@club.id).save!
-      Club.all.merge!(:includes => :sponsored_member).find(@club.id).save!
+      Club.all.merge!(includes: :sponsored_member).find(@club.id).save!
     end
   end
 
   def test_through_belongs_to_after_destroy
-    @member_detail = MemberDetail.new(:extra_data => 'Extra')
+    @member_detail = MemberDetail.new(extra_data: "Extra")
     @member.member_detail = @member_detail
     @member.save!
 
@@ -261,7 +270,7 @@ class HasOneThroughAssociationsTest < ActiveRecord::TestCase
   end
 
   def test_value_is_properly_quoted
-    minivan = Minivan.find('m1')
+    minivan = Minivan.find("m1")
     assert_nothing_raised do
       minivan.dashboard
     end
@@ -270,7 +279,7 @@ class HasOneThroughAssociationsTest < ActiveRecord::TestCase
   def test_has_one_through_polymorphic_with_primary_key_option
     assert_equal categories(:general), authors(:david).essay_category
 
-    authors = Author.joins(:essay_category).where('categories.id' => categories(:general).id)
+    authors = Author.joins(:essay_category).where("categories.id" => categories(:general).id)
     assert_equal authors(:david), authors.first
 
     assert_equal owners(:blackbeard), authors(:david).essay_owner
@@ -282,12 +291,12 @@ class HasOneThroughAssociationsTest < ActiveRecord::TestCase
   def test_has_one_through_with_primary_key_option
     assert_equal categories(:general), authors(:david).essay_category_2
 
-    authors = Author.joins(:essay_category_2).where('categories.id' => categories(:general).id)
+    authors = Author.joins(:essay_category_2).where("categories.id" => categories(:general).id)
     assert_equal authors(:david), authors.first
   end
 
   def test_has_one_through_with_default_scope_on_join_model
-    assert_equal posts(:welcome).comments.order('id').first, authors(:david).comment_on_first_post
+    assert_equal posts(:welcome).comments.order("id").first, authors(:david).comment_on_first_post
   end
 
   def test_has_one_through_many_raises_exception
diff --git a/activerecord/test/cases/associations/inner_join_association_test.rb b/activerecord/test/cases/associations/inner_join_association_test.rb
index b3fe759ad9..7be875fec6 100644
--- a/activerecord/test/cases/associations/inner_join_association_test.rb
+++ b/activerecord/test/cases/associations/inner_join_association_test.rb
@@ -1,16 +1,18 @@
+# frozen_string_literal: true
+
 require "cases/helper"
-require 'models/post'
-require 'models/comment'
-require 'models/author'
-require 'models/essay'
-require 'models/category'
-require 'models/categorization'
-require 'models/person'
-require 'models/tagging'
-require 'models/tag'
+require "models/post"
+require "models/comment"
+require "models/author"
+require "models/essay"
+require "models/category"
+require "models/categorization"
+require "models/person"
+require "models/tagging"
+require "models/tag"
 
 class InnerJoinAssociationTest < ActiveRecord::TestCase
-  fixtures :authors, :essays, :posts, :comments, :categories, :categories_posts, :categorizations,
+  fixtures :authors, :author_addresses, :essays, :posts, :comments, :categories, :categories_posts, :categorizations,
            :taggings, :tags
 
   def test_construct_finder_sql_applies_aliases_tables_on_association_conditions
@@ -20,11 +22,29 @@ class InnerJoinAssociationTest < ActiveRecord::TestCase
 
   def test_construct_finder_sql_does_not_table_name_collide_on_duplicate_associations
     assert_nothing_raised do
-      sql = Person.joins(:agents => {:agents => :agents}).joins(:agents => {:agents => {:primary_contact => :agents}}).to_sql
+      sql = Person.joins(agents: { agents: :agents }).joins(agents: { agents: { primary_contact: :agents } }).to_sql
       assert_match(/agents_people_4/i, sql)
     end
   end
 
+  def test_construct_finder_sql_does_not_table_name_collide_on_duplicate_associations_with_left_outer_joins
+    sql = Person.joins(agents: :agents).left_outer_joins(agents: :agents).to_sql
+    assert_match(/agents_people_4/i, sql)
+  end
+
+  def test_construct_finder_sql_does_not_table_name_collide_with_string_joins
+    sql = Person.joins(:agents).joins("JOIN people agents_people ON agents_people.primary_contact_id = people.id").to_sql
+    assert_match(/agents_people_2/i, sql)
+  end
+
+  def test_construct_finder_sql_does_not_table_name_collide_with_aliased_joins
+    people = Person.arel_table
+    agents = people.alias("agents_people")
+    constraint = agents[:primary_contact_id].eq(people[:id])
+    sql = Person.joins(:agents).joins(agents.create_join(agents, agents.create_on(constraint))).to_sql
+    assert_match(/agents_people_2/i, sql)
+  end
+
   def test_construct_finder_sql_ignores_empty_joins_hash
     sql = Author.joins({}).to_sql
     assert_no_match(/JOIN/i, sql)
@@ -47,7 +67,7 @@ class InnerJoinAssociationTest < ActiveRecord::TestCase
   end
 
   def test_join_conditions_allow_nil_associations
-    authors = Author.includes(:essays).where(:essays => {:id => nil})
+    authors = Author.includes(:essays).where(essays: { id: nil })
     assert_equal 2, authors.count
   end
 
@@ -58,41 +78,41 @@ class InnerJoinAssociationTest < ActiveRecord::TestCase
   end
 
   def test_find_with_implicit_inner_joins_honors_readonly_with_select
-    authors = Author.joins(:posts).select('authors.*').to_a
+    authors = Author.joins(:posts).select("authors.*").to_a
     assert !authors.empty?, "expected authors to be non-empty"
-    assert authors.all? {|a| !a.readonly? }, "expected no authors to be readonly"
+    assert authors.all? { |a| !a.readonly? }, "expected no authors to be readonly"
   end
 
   def test_find_with_implicit_inner_joins_honors_readonly_false
     authors = Author.joins(:posts).readonly(false).to_a
     assert !authors.empty?, "expected authors to be non-empty"
-    assert authors.all? {|a| !a.readonly? }, "expected no authors to be readonly"
+    assert authors.all? { |a| !a.readonly? }, "expected no authors to be readonly"
   end
 
   def test_find_with_implicit_inner_joins_does_not_set_associations
-    authors = Author.joins(:posts).select('authors.*').to_a
+    authors = Author.joins(:posts).select("authors.*").to_a
     assert !authors.empty?, "expected authors to be non-empty"
     assert authors.all? { |a| !a.instance_variable_defined?(:@posts) }, "expected no authors to have the @posts association loaded"
   end
 
   def test_count_honors_implicit_inner_joins
-    real_count = Author.all.to_a.sum{|a| a.posts.count }
+    real_count = Author.all.to_a.sum { |a| a.posts.count }
     assert_equal real_count, Author.joins(:posts).count, "plain inner join count should match the number of referenced posts records"
   end
 
   def test_calculate_honors_implicit_inner_joins
-    real_count = Author.all.to_a.sum{|a| a.posts.count }
-    assert_equal real_count, Author.joins(:posts).calculate(:count, 'authors.id'), "plain inner join count should match the number of referenced posts records"
+    real_count = Author.all.to_a.sum { |a| a.posts.count }
+    assert_equal real_count, Author.joins(:posts).calculate(:count, "authors.id"), "plain inner join count should match the number of referenced posts records"
   end
 
   def test_calculate_honors_implicit_inner_joins_and_distinct_and_conditions
-    real_count = Author.all.to_a.select {|a| a.posts.any? {|p| p.title =~ /^Welcome/} }.length
-    authors_with_welcoming_post_titles = Author.all.merge!(joins: :posts, where: "posts.title like 'Welcome%'").distinct.calculate(:count, 'authors.id')
+    real_count = Author.all.to_a.select { |a| a.posts.any? { |p| p.title.start_with?("Welcome") } }.length
+    authors_with_welcoming_post_titles = Author.all.merge!(joins: :posts, where: "posts.title like 'Welcome%'").distinct.calculate(:count, "authors.id")
     assert_equal real_count, authors_with_welcoming_post_titles, "inner join and conditions should have only returned authors posting titles starting with 'Welcome'"
   end
 
   def test_find_with_sti_join
-    scope = Post.joins(:special_comments).where(:id => posts(:sti_comments).id)
+    scope = Post.joins(:special_comments).where(id: posts(:sti_comments).id)
 
     # The join should match SpecialComment and its subclasses only
     assert scope.where("comments.type" => "Comment").empty?
@@ -102,12 +122,12 @@ class InnerJoinAssociationTest < ActiveRecord::TestCase
 
   def test_find_with_conditions_on_reflection
     assert !posts(:welcome).comments.empty?
-    assert Post.joins(:nonexistent_comments).where(:id => posts(:welcome).id).empty? # [sic!]
+    assert Post.joins(:nonexistent_comments).where(id: posts(:welcome).id).empty? # [sic!]
   end
 
   def test_find_with_conditions_on_through_reflection
     assert !posts(:welcome).tags.empty?
-    assert Post.joins(:misc_tags).where(:id => posts(:welcome).id).empty?
+    assert Post.joins(:misc_tags).where(id: posts(:welcome).id).empty?
   end
 
   test "the default scope of the target is applied when joining associations" do
@@ -120,8 +140,8 @@ class InnerJoinAssociationTest < ActiveRecord::TestCase
 
   test "the default scope of the target is correctly aliased when joining associations" do
     author = Author.create! name: "Jon"
-    author.categories.create! name: 'Not Special'
-    author.special_categories.create! name: 'Special'
+    author.categories.create! name: "Not Special"
+    author.special_categories.create! name: "Special"
 
     categories = author.categories.includes(:special_categorizations).references(:special_categorizations).to_a
     assert_equal 2, categories.size
@@ -129,8 +149,8 @@ class InnerJoinAssociationTest < ActiveRecord::TestCase
 
   test "the correct records are loaded when including an aliased association" do
     author = Author.create! name: "Jon"
-    author.categories.create! name: 'Not Special'
-    author.special_categories.create! name: 'Special'
+    author.categories.create! name: "Not Special"
+    author.special_categories.create! name: "Special"
 
     categories = author.categories.eager_load(:special_categorizations).order(:name).to_a
     assert_equal 0, categories.first.special_categorizations.size
diff --git a/activerecord/test/cases/associations/inverse_associations_test.rb b/activerecord/test/cases/associations/inverse_associations_test.rb
index c9743e80d3..c0d328ca8a 100644
--- a/activerecord/test/cases/associations/inverse_associations_test.rb
+++ b/activerecord/test/cases/associations/inverse_associations_test.rb
@@ -1,21 +1,25 @@
+# frozen_string_literal: true
+
 require "cases/helper"
-require 'models/man'
-require 'models/face'
-require 'models/interest'
-require 'models/zine'
-require 'models/club'
-require 'models/sponsor'
-require 'models/rating'
-require 'models/comment'
-require 'models/car'
-require 'models/bulb'
-require 'models/mixed_case_monkey'
-require 'models/admin'
-require 'models/admin/account'
-require 'models/admin/user'
-require 'models/developer'
-require 'models/company'
-require 'models/project'
+require "models/man"
+require "models/face"
+require "models/interest"
+require "models/zine"
+require "models/club"
+require "models/sponsor"
+require "models/rating"
+require "models/comment"
+require "models/car"
+require "models/bulb"
+require "models/mixed_case_monkey"
+require "models/admin"
+require "models/admin/account"
+require "models/admin/user"
+require "models/developer"
+require "models/company"
+require "models/project"
+require "models/author"
+require "models/post"
 
 class AutomaticInverseFindingTests < ActiveRecord::TestCase
   fixtures :ratings, :comments, :cars
@@ -24,11 +28,9 @@ class AutomaticInverseFindingTests < ActiveRecord::TestCase
     monkey_reflection = MixedCaseMonkey.reflect_on_association(:man)
     man_reflection = Man.reflect_on_association(:mixed_case_monkey)
 
-    assert_respond_to monkey_reflection, :has_inverse?
     assert monkey_reflection.has_inverse?, "The monkey reflection should have an inverse"
     assert_equal man_reflection, monkey_reflection.inverse_of, "The monkey reflection's inverse should be the man reflection"
 
-    assert_respond_to man_reflection, :has_inverse?
     assert man_reflection.has_inverse?, "The man reflection should have an inverse"
     assert_equal monkey_reflection, man_reflection.inverse_of, "The man reflection's inverse should be the monkey reflection"
   end
@@ -37,7 +39,6 @@ class AutomaticInverseFindingTests < ActiveRecord::TestCase
     account_reflection = Admin::Account.reflect_on_association(:users)
     user_reflection = Admin::User.reflect_on_association(:account)
 
-    assert_respond_to account_reflection, :has_inverse?
     assert account_reflection.has_inverse?, "The Admin::Account reflection should have an inverse"
     assert_equal user_reflection, account_reflection.inverse_of, "The Admin::Account reflection's inverse should be the Admin::User reflection"
   end
@@ -46,11 +47,9 @@ class AutomaticInverseFindingTests < ActiveRecord::TestCase
     car_reflection = Car.reflect_on_association(:bulb)
     bulb_reflection = Bulb.reflect_on_association(:car)
 
-    assert_respond_to car_reflection, :has_inverse?
     assert car_reflection.has_inverse?, "The Car reflection should have an inverse"
     assert_equal bulb_reflection, car_reflection.inverse_of, "The Car reflection's inverse should be the Bulb reflection"
 
-    assert_respond_to bulb_reflection, :has_inverse?
     assert bulb_reflection.has_inverse?, "The Bulb reflection should have an inverse"
     assert_equal car_reflection, bulb_reflection.inverse_of, "The Bulb reflection's inverse should be the Car reflection"
   end
@@ -59,11 +58,24 @@ class AutomaticInverseFindingTests < ActiveRecord::TestCase
     comment_reflection = Comment.reflect_on_association(:ratings)
     rating_reflection = Rating.reflect_on_association(:comment)
 
-    assert_respond_to comment_reflection, :has_inverse?
     assert comment_reflection.has_inverse?, "The Comment reflection should have an inverse"
     assert_equal rating_reflection, comment_reflection.inverse_of, "The Comment reflection's inverse should be the Rating reflection"
   end
 
+  def test_has_many_and_belongs_to_should_find_inverse_automatically_for_sti
+    author_reflection = Author.reflect_on_association(:posts)
+    author_child_reflection = Author.reflect_on_association(:special_posts)
+    post_reflection = Post.reflect_on_association(:author)
+
+    assert_respond_to author_reflection, :has_inverse?
+    assert author_reflection.has_inverse?, "The Author reflection should have an inverse"
+    assert_equal post_reflection, author_reflection.inverse_of, "The Author reflection's inverse should be the Post reflection"
+
+    assert_respond_to author_child_reflection, :has_inverse?
+    assert author_child_reflection.has_inverse?, "The Author reflection should have an inverse"
+    assert_equal post_reflection, author_child_reflection.inverse_of, "The Author reflection's inverse should be the Post reflection"
+  end
+
   def test_has_one_and_belongs_to_automatic_inverse_shares_objects
     car = Car.first
     bulb = Bulb.create!(car: car)
@@ -107,79 +119,55 @@ class AutomaticInverseFindingTests < ActiveRecord::TestCase
   def test_polymorphic_and_has_many_through_relationships_should_not_have_inverses
     sponsor_reflection = Sponsor.reflect_on_association(:sponsorable)
 
-    assert_respond_to sponsor_reflection, :has_inverse?
     assert !sponsor_reflection.has_inverse?, "A polymorphic association should not find an inverse automatically"
 
     club_reflection = Club.reflect_on_association(:members)
 
-    assert_respond_to club_reflection, :has_inverse?
     assert !club_reflection.has_inverse?, "A has_many_through association should not find an inverse automatically"
   end
 
-  def test_polymorphic_relationships_should_still_not_have_inverses_when_non_polymorphic_relationship_has_the_same_name
+  def test_polymorphic_has_one_should_find_inverse_automatically
     man_reflection = Man.reflect_on_association(:polymorphic_face_without_inverse)
-    face_reflection = Face.reflect_on_association(:man)
-
-    assert_respond_to face_reflection, :has_inverse?
-    assert face_reflection.has_inverse?, "For this test, the non-polymorphic association must have an inverse"
 
-    assert_respond_to man_reflection, :has_inverse?
-    assert !man_reflection.has_inverse?, "The target of a polymorphic association should not find an inverse automatically"
+    assert man_reflection.has_inverse?
   end
 end
 
 class InverseAssociationTests < ActiveRecord::TestCase
   def test_should_allow_for_inverse_of_options_in_associations
     assert_nothing_raised do
-      Class.new(ActiveRecord::Base).has_many(:wheels, :inverse_of => :car)
+      Class.new(ActiveRecord::Base).has_many(:wheels, inverse_of: :car)
     end
 
     assert_nothing_raised do
-      Class.new(ActiveRecord::Base).has_one(:engine, :inverse_of => :car)
+      Class.new(ActiveRecord::Base).has_one(:engine, inverse_of: :car)
     end
 
     assert_nothing_raised do
-      Class.new(ActiveRecord::Base).belongs_to(:car, :inverse_of => :driver)
+      Class.new(ActiveRecord::Base).belongs_to(:car, inverse_of: :driver)
     end
   end
 
   def test_should_be_able_to_ask_a_reflection_if_it_has_an_inverse
     has_one_with_inverse_ref = Man.reflect_on_association(:face)
-    assert_respond_to has_one_with_inverse_ref, :has_inverse?
     assert has_one_with_inverse_ref.has_inverse?
 
     has_many_with_inverse_ref = Man.reflect_on_association(:interests)
-    assert_respond_to has_many_with_inverse_ref, :has_inverse?
     assert has_many_with_inverse_ref.has_inverse?
 
     belongs_to_with_inverse_ref = Face.reflect_on_association(:man)
-    assert_respond_to belongs_to_with_inverse_ref, :has_inverse?
     assert belongs_to_with_inverse_ref.has_inverse?
 
     has_one_without_inverse_ref = Club.reflect_on_association(:sponsor)
-    assert_respond_to has_one_without_inverse_ref, :has_inverse?
     assert !has_one_without_inverse_ref.has_inverse?
 
     has_many_without_inverse_ref = Club.reflect_on_association(:memberships)
-    assert_respond_to has_many_without_inverse_ref, :has_inverse?
     assert !has_many_without_inverse_ref.has_inverse?
 
     belongs_to_without_inverse_ref = Sponsor.reflect_on_association(:sponsor_club)
-    assert_respond_to belongs_to_without_inverse_ref, :has_inverse?
     assert !belongs_to_without_inverse_ref.has_inverse?
   end
 
-  def test_should_be_able_to_ask_a_reflection_what_it_is_the_inverse_of
-    has_one_ref = Man.reflect_on_association(:face)
-    assert_respond_to has_one_ref, :inverse_of
-
-    has_many_ref = Man.reflect_on_association(:interests)
-    assert_respond_to has_many_ref, :inverse_of
-
-    belongs_to_ref = Face.reflect_on_association(:man)
-    assert_respond_to belongs_to_ref, :inverse_of
-  end
-
   def test_inverse_of_method_should_supply_the_actual_reflection_instance_it_is_the_inverse_of
     has_one_ref = Man.reflect_on_association(:face)
     assert_equal Face.reflect_on_association(:man), has_one_ref.inverse_of
@@ -203,9 +191,9 @@ class InverseAssociationTests < ActiveRecord::TestCase
   end
 
   def test_this_inverse_stuff
-    firm = Firm.create!(name: 'Adequate Holdings')
-    Project.create!(name: 'Project 1', firm: firm)
-    Developer.create!(name: 'Gorbypuff', firm: firm)
+    firm = Firm.create!(name: "Adequate Holdings")
+    Project.create!(name: "Project 1", firm: firm)
+    Developer.create!(name: "Gorbypuff", firm: firm)
 
     new_project = Project.last
     assert Project.reflect_on_association(:lead_developer).inverse_of.present?, "Expected inverse of to be present"
@@ -220,73 +208,72 @@ class InverseHasOneTests < ActiveRecord::TestCase
     m = men(:gordon)
     f = m.face
     assert_equal m.name, f.man.name, "Name of man should be the same before changes to parent instance"
-    m.name = 'Bongo'
+    m.name = "Bongo"
     assert_equal m.name, f.man.name, "Name of man should be the same after changes to parent instance"
-    f.man.name = 'Mungo'
+    f.man.name = "Mungo"
     assert_equal m.name, f.man.name, "Name of man should be the same after changes to child-owned instance"
   end
 
-
   def test_parent_instance_should_be_shared_with_eager_loaded_child_on_find
-    m = Man.all.merge!(:where => {:name => 'Gordon'}, :includes => :face).first
+    m = Man.all.merge!(where: { name: "Gordon" }, includes: :face).first
     f = m.face
     assert_equal m.name, f.man.name, "Name of man should be the same before changes to parent instance"
-    m.name = 'Bongo'
+    m.name = "Bongo"
     assert_equal m.name, f.man.name, "Name of man should be the same after changes to parent instance"
-    f.man.name = 'Mungo'
+    f.man.name = "Mungo"
     assert_equal m.name, f.man.name, "Name of man should be the same after changes to child-owned instance"
 
-    m = Man.all.merge!(:where => {:name => 'Gordon'}, :includes => :face, :order => 'faces.id').first
+    m = Man.all.merge!(where: { name: "Gordon" }, includes: :face, order: "faces.id").first
     f = m.face
     assert_equal m.name, f.man.name, "Name of man should be the same before changes to parent instance"
-    m.name = 'Bongo'
+    m.name = "Bongo"
     assert_equal m.name, f.man.name, "Name of man should be the same after changes to parent instance"
-    f.man.name = 'Mungo'
+    f.man.name = "Mungo"
     assert_equal m.name, f.man.name, "Name of man should be the same after changes to child-owned instance"
   end
 
   def test_parent_instance_should_be_shared_with_newly_built_child
     m = Man.first
-    f = m.build_face(:description => 'haunted')
+    f = m.build_face(description: "haunted")
     assert_not_nil f.man
     assert_equal m.name, f.man.name, "Name of man should be the same before changes to parent instance"
-    m.name = 'Bongo'
+    m.name = "Bongo"
     assert_equal m.name, f.man.name, "Name of man should be the same after changes to parent instance"
-    f.man.name = 'Mungo'
+    f.man.name = "Mungo"
     assert_equal m.name, f.man.name, "Name of man should be the same after changes to just-built-child-owned instance"
   end
 
   def test_parent_instance_should_be_shared_with_newly_created_child
     m = Man.first
-    f = m.create_face(:description => 'haunted')
+    f = m.create_face(description: "haunted")
     assert_not_nil f.man
     assert_equal m.name, f.man.name, "Name of man should be the same before changes to parent instance"
-    m.name = 'Bongo'
+    m.name = "Bongo"
     assert_equal m.name, f.man.name, "Name of man should be the same after changes to parent instance"
-    f.man.name = 'Mungo'
+    f.man.name = "Mungo"
     assert_equal m.name, f.man.name, "Name of man should be the same after changes to newly-created-child-owned instance"
   end
 
   def test_parent_instance_should_be_shared_with_newly_created_child_via_bang_method
     m = Man.first
-    f = m.create_face!(:description => 'haunted')
+    f = m.create_face!(description: "haunted")
     assert_not_nil f.man
     assert_equal m.name, f.man.name, "Name of man should be the same before changes to parent instance"
-    m.name = 'Bongo'
+    m.name = "Bongo"
     assert_equal m.name, f.man.name, "Name of man should be the same after changes to parent instance"
-    f.man.name = 'Mungo'
+    f.man.name = "Mungo"
     assert_equal m.name, f.man.name, "Name of man should be the same after changes to newly-created-child-owned instance"
   end
 
   def test_parent_instance_should_be_shared_with_replaced_via_accessor_child
     m = Man.first
-    f = Face.new(:description => 'haunted')
+    f = Face.new(description: "haunted")
     m.face = f
     assert_not_nil f.man
     assert_equal m.name, f.man.name, "Name of man should be the same before changes to parent instance"
-    m.name = 'Bongo'
+    m.name = "Bongo"
     assert_equal m.name, f.man.name, "Name of man should be the same after changes to parent instance"
-    f.man.name = 'Mungo'
+    f.man.name = "Mungo"
     assert_equal m.name, f.man.name, "Name of man should be the same after changes to replaced-child-owned instance"
   end
 
@@ -296,74 +283,95 @@ class InverseHasOneTests < ActiveRecord::TestCase
 end
 
 class InverseHasManyTests < ActiveRecord::TestCase
-  fixtures :men, :interests
+  fixtures :men, :interests, :posts, :authors, :author_addresses
 
   def test_parent_instance_should_be_shared_with_every_child_on_find
     m = men(:gordon)
     is = m.interests
     is.each do |i|
       assert_equal m.name, i.man.name, "Name of man should be the same before changes to parent instance"
-      m.name = 'Bongo'
+      m.name = "Bongo"
       assert_equal m.name, i.man.name, "Name of man should be the same after changes to parent instance"
-      i.man.name = 'Mungo'
+      i.man.name = "Mungo"
       assert_equal m.name, i.man.name, "Name of man should be the same after changes to child-owned instance"
     end
   end
 
+  def test_parent_instance_should_be_shared_with_every_child_on_find_for_sti
+    a = authors(:david)
+    ps = a.posts
+    ps.each do |p|
+      assert_equal a.name, p.author.name, "Name of man should be the same before changes to parent instance"
+      a.name = "Bongo"
+      assert_equal a.name, p.author.name, "Name of man should be the same after changes to parent instance"
+      p.author.name = "Mungo"
+      assert_equal a.name, p.author.name, "Name of man should be the same after changes to child-owned instance"
+    end
+
+    sps = a.special_posts
+    sps.each do |sp|
+      assert_equal a.name, sp.author.name, "Name of man should be the same before changes to parent instance"
+      a.name = "Bongo"
+      assert_equal a.name, sp.author.name, "Name of man should be the same after changes to parent instance"
+      sp.author.name = "Mungo"
+      assert_equal a.name, sp.author.name, "Name of man should be the same after changes to child-owned instance"
+    end
+  end
+
   def test_parent_instance_should_be_shared_with_eager_loaded_children
-    m = Man.all.merge!(:where => {:name => 'Gordon'}, :includes => :interests).first
+    m = Man.all.merge!(where: { name: "Gordon" }, includes: :interests).first
     is = m.interests
     is.each do |i|
       assert_equal m.name, i.man.name, "Name of man should be the same before changes to parent instance"
-      m.name = 'Bongo'
+      m.name = "Bongo"
       assert_equal m.name, i.man.name, "Name of man should be the same after changes to parent instance"
-      i.man.name = 'Mungo'
+      i.man.name = "Mungo"
       assert_equal m.name, i.man.name, "Name of man should be the same after changes to child-owned instance"
     end
 
-    m = Man.all.merge!(:where => {:name => 'Gordon'}, :includes => :interests, :order => 'interests.id').first
+    m = Man.all.merge!(where: { name: "Gordon" }, includes: :interests, order: "interests.id").first
     is = m.interests
     is.each do |i|
       assert_equal m.name, i.man.name, "Name of man should be the same before changes to parent instance"
-      m.name = 'Bongo'
+      m.name = "Bongo"
       assert_equal m.name, i.man.name, "Name of man should be the same after changes to parent instance"
-      i.man.name = 'Mungo'
+      i.man.name = "Mungo"
       assert_equal m.name, i.man.name, "Name of man should be the same after changes to child-owned instance"
     end
   end
 
   def test_parent_instance_should_be_shared_with_newly_block_style_built_child
     m = Man.first
-    i = m.interests.build {|ii| ii.topic = 'Industrial Revolution Re-enactment'}
+    i = m.interests.build { |ii| ii.topic = "Industrial Revolution Re-enactment" }
     assert_not_nil i.topic, "Child attributes supplied to build via blocks should be populated"
     assert_not_nil i.man
     assert_equal m.name, i.man.name, "Name of man should be the same before changes to parent instance"
-    m.name = 'Bongo'
+    m.name = "Bongo"
     assert_equal m.name, i.man.name, "Name of man should be the same after changes to parent instance"
-    i.man.name = 'Mungo'
+    i.man.name = "Mungo"
     assert_equal m.name, i.man.name, "Name of man should be the same after changes to just-built-child-owned instance"
   end
 
   def test_parent_instance_should_be_shared_with_newly_created_via_bang_method_child
     m = Man.first
-    i = m.interests.create!(:topic => 'Industrial Revolution Re-enactment')
+    i = m.interests.create!(topic: "Industrial Revolution Re-enactment")
     assert_not_nil i.man
     assert_equal m.name, i.man.name, "Name of man should be the same before changes to parent instance"
-    m.name = 'Bongo'
+    m.name = "Bongo"
     assert_equal m.name, i.man.name, "Name of man should be the same after changes to parent instance"
-    i.man.name = 'Mungo'
+    i.man.name = "Mungo"
     assert_equal m.name, i.man.name, "Name of man should be the same after changes to newly-created-child-owned instance"
   end
 
   def test_parent_instance_should_be_shared_with_newly_block_style_created_child
     m = Man.first
-    i = m.interests.create {|ii| ii.topic = 'Industrial Revolution Re-enactment'}
+    i = m.interests.create { |ii| ii.topic = "Industrial Revolution Re-enactment" }
     assert_not_nil i.topic, "Child attributes supplied to create via blocks should be populated"
     assert_not_nil i.man
     assert_equal m.name, i.man.name, "Name of man should be the same before changes to parent instance"
-    m.name = 'Bongo'
+    m.name = "Bongo"
     assert_equal m.name, i.man.name, "Name of man should be the same after changes to parent instance"
-    i.man.name = 'Mungo'
+    i.man.name = "Mungo"
     assert_equal m.name, i.man.name, "Name of man should be the same after changes to newly-created-child-owned instance"
   end
 
@@ -385,25 +393,25 @@ class InverseHasManyTests < ActiveRecord::TestCase
 
   def test_parent_instance_should_be_shared_with_poked_in_child
     m = men(:gordon)
-    i = Interest.create(:topic => 'Industrial Revolution Re-enactment')
+    i = Interest.create(topic: "Industrial Revolution Re-enactment")
     m.interests << i
     assert_not_nil i.man
     assert_equal m.name, i.man.name, "Name of man should be the same before changes to parent instance"
-    m.name = 'Bongo'
+    m.name = "Bongo"
     assert_equal m.name, i.man.name, "Name of man should be the same after changes to parent instance"
-    i.man.name = 'Mungo'
+    i.man.name = "Mungo"
     assert_equal m.name, i.man.name, "Name of man should be the same after changes to newly-created-child-owned instance"
   end
 
   def test_parent_instance_should_be_shared_with_replaced_via_accessor_children
     m = Man.first
-    i = Interest.new(:topic => 'Industrial Revolution Re-enactment')
+    i = Interest.new(topic: "Industrial Revolution Re-enactment")
     m.interests = [i]
     assert_not_nil i.man
     assert_equal m.name, i.man.name, "Name of man should be the same before changes to parent instance"
-    m.name = 'Bongo'
+    m.name = "Bongo"
     assert_equal m.name, i.man.name, "Name of man should be the same after changes to parent instance"
-    i.man.name = 'Mungo'
+    i.man.name = "Mungo"
     assert_equal m.name, i.man.name, "Name of man should be the same after changes to replaced-child-owned instance"
   end
 
@@ -444,7 +452,7 @@ class InverseHasManyTests < ActiveRecord::TestCase
     assert man.equal?(man.interests.first.man), "Two inverses should lead back to the same object that was originally held"
     assert man.equal?(man.interests.find(interest.id).man), "Two inversions should lead back to the same object that was originally held"
 
-    assert_equal man.name, man.interests.find(interest.id).man.name, "The name of the man should match before the name is changed"
+    assert_nil man.interests.find(interest.id).man.name, "The name of the man should match before the name is changed"
     man.name = "Ben Bitdiddle"
     assert_equal man.name, man.interests.find(interest.id).man.name, "The name of the man should match after the parent name is changed"
     man.interests.find(interest.id).man.name = "Alyssa P. Hacker"
@@ -476,7 +484,10 @@ class InverseHasManyTests < ActiveRecord::TestCase
   def test_raise_record_not_found_error_when_no_ids_are_passed
     man = Man.create!
 
-    assert_raise(ActiveRecord::RecordNotFound) { man.interests.find() }
+    exception = assert_raise(ActiveRecord::RecordNotFound) { man.interests.load.find() }
+
+    assert_equal exception.model, "Interest"
+    assert_equal exception.primary_key, "id"
   end
 
   def test_trying_to_use_inverses_that_dont_exist_should_raise_an_error
@@ -485,7 +496,7 @@ class InverseHasManyTests < ActiveRecord::TestCase
 
   def test_child_instance_should_point_to_parent_without_saving
     man = Man.new
-    i = Interest.create(:topic => 'Industrial Revolution Re-enactment')
+    i = Interest.create(topic: "Industrial Revolution Re-enactment")
 
     man.interests << i
     assert_not_nil i.man
@@ -495,6 +506,33 @@ class InverseHasManyTests < ActiveRecord::TestCase
 
     assert !man.persisted?
   end
+
+  def test_inverse_instance_should_be_set_before_find_callbacks_are_run
+    reset_callbacks(Interest, :find) do
+      Interest.after_find { raise unless association(:man).loaded? && man.present? }
+
+      assert Man.first.interests.reload.any?
+      assert Man.includes(:interests).first.interests.any?
+      assert Man.joins(:interests).includes(:interests).first.interests.any?
+    end
+  end
+
+  def test_inverse_instance_should_be_set_before_initialize_callbacks_are_run
+    reset_callbacks(Interest, :initialize) do
+      Interest.after_initialize { raise unless association(:man).loaded? && man.present? }
+
+      assert Man.first.interests.reload.any?
+      assert Man.includes(:interests).first.interests.any?
+      assert Man.joins(:interests).includes(:interests).first.interests.any?
+    end
+  end
+
+  def reset_callbacks(target, type)
+    old_callbacks = target.send(:get_callbacks, type).deep_dup
+    yield
+  ensure
+    target.send(:set_callbacks, type, old_callbacks) if old_callbacks
+  end
 end
 
 class InverseBelongsToTests < ActiveRecord::TestCase
@@ -504,49 +542,49 @@ class InverseBelongsToTests < ActiveRecord::TestCase
     f = faces(:trusting)
     m = f.man
     assert_equal f.description, m.face.description, "Description of face should be the same before changes to child instance"
-    f.description = 'gormless'
+    f.description = "gormless"
     assert_equal f.description, m.face.description, "Description of face should be the same after changes to child instance"
-    m.face.description = 'pleasing'
+    m.face.description = "pleasing"
     assert_equal f.description, m.face.description, "Description of face should be the same after changes to parent-owned instance"
   end
 
   def test_eager_loaded_child_instance_should_be_shared_with_parent_on_find
-    f = Face.all.merge!(:includes => :man, :where => {:description => 'trusting'}).first
+    f = Face.all.merge!(includes: :man, where: { description: "trusting" }).first
     m = f.man
     assert_equal f.description, m.face.description, "Description of face should be the same before changes to child instance"
-    f.description = 'gormless'
+    f.description = "gormless"
     assert_equal f.description, m.face.description, "Description of face should be the same after changes to child instance"
-    m.face.description = 'pleasing'
+    m.face.description = "pleasing"
     assert_equal f.description, m.face.description, "Description of face should be the same after changes to parent-owned instance"
 
-    f = Face.all.merge!(:includes => :man, :order => 'men.id', :where => {:description => 'trusting'}).first
+    f = Face.all.merge!(includes: :man, order: "men.id", where: { description: "trusting" }).first
     m = f.man
     assert_equal f.description, m.face.description, "Description of face should be the same before changes to child instance"
-    f.description = 'gormless'
+    f.description = "gormless"
     assert_equal f.description, m.face.description, "Description of face should be the same after changes to child instance"
-    m.face.description = 'pleasing'
+    m.face.description = "pleasing"
     assert_equal f.description, m.face.description, "Description of face should be the same after changes to parent-owned instance"
   end
 
   def test_child_instance_should_be_shared_with_newly_built_parent
     f = faces(:trusting)
-    m = f.build_man(:name => 'Charles')
+    m = f.build_man(name: "Charles")
     assert_not_nil m.face
     assert_equal f.description, m.face.description, "Description of face should be the same before changes to child instance"
-    f.description = 'gormless'
+    f.description = "gormless"
     assert_equal f.description, m.face.description, "Description of face should be the same after changes to child instance"
-    m.face.description = 'pleasing'
+    m.face.description = "pleasing"
     assert_equal f.description, m.face.description, "Description of face should be the same after changes to just-built-parent-owned instance"
   end
 
   def test_child_instance_should_be_shared_with_newly_created_parent
     f = faces(:trusting)
-    m = f.create_man(:name => 'Charles')
+    m = f.create_man(name: "Charles")
     assert_not_nil m.face
     assert_equal f.description, m.face.description, "Description of face should be the same before changes to child instance"
-    f.description = 'gormless'
+    f.description = "gormless"
     assert_equal f.description, m.face.description, "Description of face should be the same after changes to child instance"
-    m.face.description = 'pleasing'
+    m.face.description = "pleasing"
     assert_equal f.description, m.face.description, "Description of face should be the same after changes to newly-created-parent-owned instance"
   end
 
@@ -554,24 +592,24 @@ class InverseBelongsToTests < ActiveRecord::TestCase
     i = interests(:trainspotting)
     m = i.man
     assert_not_nil m.interests
-    iz = m.interests.detect { |_iz| _iz.id == i.id}
+    iz = m.interests.detect { |_iz| _iz.id == i.id }
     assert_not_nil iz
     assert_equal i.topic, iz.topic, "Interest topics should be the same before changes to child"
-    i.topic = 'Eating cheese with a spoon'
+    i.topic = "Eating cheese with a spoon"
     assert_not_equal i.topic, iz.topic, "Interest topics should not be the same after changes to child"
-    iz.topic = 'Cow tipping'
+    iz.topic = "Cow tipping"
     assert_not_equal i.topic, iz.topic, "Interest topics should not be the same after changes to parent-owned instance"
   end
 
   def test_child_instance_should_be_shared_with_replaced_via_accessor_parent
     f = Face.first
-    m = Man.new(:name => 'Charles')
+    m = Man.new(name: "Charles")
     f.man = m
     assert_not_nil m.face
     assert_equal f.description, m.face.description, "Description of face should be the same before changes to child instance"
-    f.description = 'gormless'
+    f.description = "gormless"
     assert_equal f.description, m.face.description, "Description of face should be the same after changes to child instance"
-    m.face.description = 'pleasing'
+    m.face.description = "pleasing"
     assert_equal f.description, m.face.description, "Description of face should be the same after changes to replaced-parent-owned instance"
   end
 
@@ -584,30 +622,30 @@ class InversePolymorphicBelongsToTests < ActiveRecord::TestCase
   fixtures :men, :faces, :interests
 
   def test_child_instance_should_be_shared_with_parent_on_find
-    f = Face.all.merge!(:where => {:description => 'confused'}).first
+    f = Face.all.merge!(where: { description: "confused" }).first
     m = f.polymorphic_man
     assert_equal f.description, m.polymorphic_face.description, "Description of face should be the same before changes to child instance"
-    f.description = 'gormless'
+    f.description = "gormless"
     assert_equal f.description, m.polymorphic_face.description, "Description of face should be the same after changes to child instance"
-    m.polymorphic_face.description = 'pleasing'
+    m.polymorphic_face.description = "pleasing"
     assert_equal f.description, m.polymorphic_face.description, "Description of face should be the same after changes to parent-owned instance"
   end
 
   def test_eager_loaded_child_instance_should_be_shared_with_parent_on_find
-    f = Face.all.merge!(:where => {:description => 'confused'}, :includes => :man).first
+    f = Face.all.merge!(where: { description: "confused" }, includes: :man).first
     m = f.polymorphic_man
     assert_equal f.description, m.polymorphic_face.description, "Description of face should be the same before changes to child instance"
-    f.description = 'gormless'
+    f.description = "gormless"
     assert_equal f.description, m.polymorphic_face.description, "Description of face should be the same after changes to child instance"
-    m.polymorphic_face.description = 'pleasing'
+    m.polymorphic_face.description = "pleasing"
     assert_equal f.description, m.polymorphic_face.description, "Description of face should be the same after changes to parent-owned instance"
 
-    f = Face.all.merge!(:where => {:description => 'confused'}, :includes => :man, :order => 'men.id').first
+    f = Face.all.merge!(where: { description: "confused" }, includes: :man, order: "men.id").first
     m = f.polymorphic_man
     assert_equal f.description, m.polymorphic_face.description, "Description of face should be the same before changes to child instance"
-    f.description = 'gormless'
+    f.description = "gormless"
     assert_equal f.description, m.polymorphic_face.description, "Description of face should be the same after changes to child instance"
-    m.polymorphic_face.description = 'pleasing'
+    m.polymorphic_face.description = "pleasing"
     assert_equal f.description, m.polymorphic_face.description, "Description of face should be the same after changes to parent-owned instance"
   end
 
@@ -619,23 +657,9 @@ class InversePolymorphicBelongsToTests < ActiveRecord::TestCase
     face.polymorphic_man = new_man
 
     assert_equal face.description, new_man.polymorphic_face.description, "Description of face should be the same before changes to parent instance"
-    face.description = 'Bongo'
-    assert_equal face.description, new_man.polymorphic_face.description, "Description of face should be the same after changes to parent instance"
-    new_man.polymorphic_face.description = 'Mungo'
-    assert_equal face.description, new_man.polymorphic_face.description, "Description of face should be the same after changes to replaced-parent-owned instance"
-  end
-
-  def test_child_instance_should_be_shared_with_replaced_via_method_parent
-    face = faces(:confused)
-    new_man = Man.new
-
-    assert_not_nil face.polymorphic_man
-    face.polymorphic_man = new_man
-
-    assert_equal face.description, new_man.polymorphic_face.description, "Description of face should be the same before changes to parent instance"
-    face.description = 'Bongo'
+    face.description = "Bongo"
     assert_equal face.description, new_man.polymorphic_face.description, "Description of face should be the same after changes to parent instance"
-    new_man.polymorphic_face.description = 'Mungo'
+    new_man.polymorphic_face.description = "Mungo"
     assert_equal face.description, new_man.polymorphic_face.description, "Description of face should be the same after changes to replaced-parent-owned instance"
   end
 
@@ -651,16 +675,26 @@ class InversePolymorphicBelongsToTests < ActiveRecord::TestCase
     assert_equal old_inversed_man.object_id, new_inversed_man.object_id
   end
 
+  def test_inversed_instance_should_not_be_reloaded_after_stale_state_changed_with_validation
+    face = Face.new man: Man.new
+
+    old_inversed_man = face.man
+    face.save!
+    new_inversed_man = face.man
+
+    assert_equal old_inversed_man.object_id, new_inversed_man.object_id
+  end
+
   def test_should_not_try_to_set_inverse_instances_when_the_inverse_is_a_has_many
     i = interests(:llama_wrangling)
     m = i.polymorphic_man
     assert_not_nil m.polymorphic_interests
-    iz = m.polymorphic_interests.detect { |_iz| _iz.id == i.id}
+    iz = m.polymorphic_interests.detect { |_iz| _iz.id == i.id }
     assert_not_nil iz
     assert_equal i.topic, iz.topic, "Interest topics should be the same before changes to child"
-    i.topic = 'Eating cheese with a spoon'
+    i.topic = "Eating cheese with a spoon"
     assert_not_equal i.topic, iz.topic, "Interest topics should not be the same after changes to child"
-    iz.topic = 'Cow tipping'
+    iz.topic = "Cow tipping"
     assert_not_equal i.topic, iz.topic, "Interest topics should not be the same after changes to parent-owned instance"
   end
 
@@ -698,8 +732,8 @@ class InverseMultipleHasManyInversesForSameModel < ActiveRecord::TestCase
   def test_that_we_can_create_associations_that_have_the_same_reciprocal_name_from_different_models
     assert_nothing_raised do
       i = Interest.first
-      i.build_zine(:title => 'Get Some in Winter! 2008')
-      i.build_man(:name => 'Gordon')
+      i.build_zine(title: "Get Some in Winter! 2008")
+      i.build_man(name: "Gordon")
       i.save!
     end
   end
diff --git a/activerecord/test/cases/associations/join_model_test.rb b/activerecord/test/cases/associations/join_model_test.rb
index 3047914b70..5d83c9435b 100644
--- a/activerecord/test/cases/associations/join_model_test.rb
+++ b/activerecord/test/cases/associations/join_model_test.rb
@@ -1,38 +1,40 @@
+# frozen_string_literal: true
+
 require "cases/helper"
-require 'models/tag'
-require 'models/tagging'
-require 'models/post'
-require 'models/rating'
-require 'models/item'
-require 'models/comment'
-require 'models/author'
-require 'models/category'
-require 'models/categorization'
-require 'models/vertex'
-require 'models/edge'
-require 'models/book'
-require 'models/citation'
-require 'models/aircraft'
-require 'models/engine'
-require 'models/car'
+require "models/tag"
+require "models/tagging"
+require "models/post"
+require "models/rating"
+require "models/item"
+require "models/comment"
+require "models/author"
+require "models/category"
+require "models/categorization"
+require "models/vertex"
+require "models/edge"
+require "models/book"
+require "models/citation"
+require "models/aircraft"
+require "models/engine"
+require "models/car"
 
 class AssociationsJoinModelTest < ActiveRecord::TestCase
   self.use_transactional_tests = false unless supports_savepoints?
 
-  fixtures :posts, :authors, :categories, :categorizations, :comments, :tags, :taggings, :author_favorites, :vertices, :items, :books,
+  fixtures :posts, :authors, :author_addresses, :categories, :categorizations, :comments, :tags, :taggings, :author_favorites, :vertices, :items, :books,
     # Reload edges table from fixtures as otherwise repeated test was failing
     :edges
 
   def test_has_many
-    assert authors(:david).categories.include?(categories(:general))
+    assert_includes authors(:david).categories, categories(:general)
   end
 
   def test_has_many_inherited
-    assert authors(:mary).categories.include?(categories(:sti_test))
+    assert_includes authors(:mary).categories, categories(:sti_test)
   end
 
   def test_inherited_has_many
-    assert categories(:sti_test).authors.include?(authors(:mary))
+    assert_includes categories(:sti_test).authors, authors(:mary)
   end
 
   def test_has_many_distinct_through_join_model
@@ -97,11 +99,11 @@ class AssociationsJoinModelTest < ActiveRecord::TestCase
   end
 
   def test_polymorphic_has_many_create_model_with_inheritance_and_custom_base_class
-    post = SubStiPost.create :title => 'SubStiPost', :body => 'SubStiPost body'
-    assert_instance_of SubStiPost, post
+    post = SubAbstractStiPost.create title: "SubAbstractStiPost", body: "SubAbstractStiPost body"
+    assert_instance_of SubAbstractStiPost, post
 
-    tagging = tags(:misc).taggings.create(:taggable => post)
-    assert_equal "SubStiPost", tagging.taggable_type
+    tagging = tags(:misc).taggings.create(taggable: post)
+    assert_equal "SubAbstractStiPost", tagging.taggable_type
   end
 
   def test_polymorphic_has_many_going_through_join_model_with_inheritance
@@ -116,12 +118,12 @@ class AssociationsJoinModelTest < ActiveRecord::TestCase
     post = posts(:thinking)
     assert_instance_of SpecialPost, post
 
-    tagging = tags(:misc).taggings.create(:taggable => post)
+    tagging = tags(:misc).taggings.create(taggable: post)
     assert_equal "Post", tagging.taggable_type
   end
 
   def test_polymorphic_has_one_create_model_with_inheritance
-    tagging = tags(:misc).create_tagging(:taggable => posts(:thinking))
+    tagging = tags(:misc).create_tagging(taggable: posts(:thinking))
     assert_equal "Post", tagging.taggable_type
   end
 
@@ -142,7 +144,7 @@ class AssociationsJoinModelTest < ActiveRecord::TestCase
 
   def test_set_polymorphic_has_one_on_new_record
     tagging = tags(:misc).taggings.create
-    post = Post.new :title => "foo", :body => "bar"
+    post = Post.new title: "foo", body: "bar"
     post.tagging = tagging
     post.save!
 
@@ -153,50 +155,50 @@ class AssociationsJoinModelTest < ActiveRecord::TestCase
 
   def test_create_polymorphic_has_many_with_scope
     old_count = posts(:welcome).taggings.count
-    tagging = posts(:welcome).taggings.create(:tag => tags(:misc))
+    tagging = posts(:welcome).taggings.create(tag: tags(:misc))
     assert_equal "Post", tagging.taggable_type
-    assert_equal old_count+1, posts(:welcome).taggings.count
+    assert_equal old_count + 1, posts(:welcome).taggings.count
   end
 
   def test_create_bang_polymorphic_with_has_many_scope
     old_count = posts(:welcome).taggings.count
-    tagging = posts(:welcome).taggings.create!(:tag => tags(:misc))
+    tagging = posts(:welcome).taggings.create!(tag: tags(:misc))
     assert_equal "Post", tagging.taggable_type
-    assert_equal old_count+1, posts(:welcome).taggings.count
+    assert_equal old_count + 1, posts(:welcome).taggings.count
   end
 
   def test_create_polymorphic_has_one_with_scope
     old_count = Tagging.count
-    tagging = posts(:welcome).create_tagging(:tag => tags(:misc))
+    tagging = posts(:welcome).create_tagging(tag: tags(:misc))
     assert_equal "Post", tagging.taggable_type
-    assert_equal old_count+1, Tagging.count
+    assert_equal old_count + 1, Tagging.count
   end
 
   def test_delete_polymorphic_has_many_with_delete_all
     assert_equal 1, posts(:welcome).taggings.count
-    posts(:welcome).taggings.first.update_columns taggable_type: 'PostWithHasManyDeleteAll'
+    posts(:welcome).taggings.first.update_columns taggable_type: "PostWithHasManyDeleteAll"
     post = find_post_with_dependency(1, :has_many, :taggings, :delete_all)
 
     old_count = Tagging.count
     post.destroy
-    assert_equal old_count-1, Tagging.count
+    assert_equal old_count - 1, Tagging.count
     assert_equal 0, posts(:welcome).taggings.count
   end
 
   def test_delete_polymorphic_has_many_with_destroy
     assert_equal 1, posts(:welcome).taggings.count
-    posts(:welcome).taggings.first.update_columns taggable_type: 'PostWithHasManyDestroy'
+    posts(:welcome).taggings.first.update_columns taggable_type: "PostWithHasManyDestroy"
     post = find_post_with_dependency(1, :has_many, :taggings, :destroy)
 
     old_count = Tagging.count
     post.destroy
-    assert_equal old_count-1, Tagging.count
+    assert_equal old_count - 1, Tagging.count
     assert_equal 0, posts(:welcome).taggings.count
   end
 
   def test_delete_polymorphic_has_many_with_nullify
     assert_equal 1, posts(:welcome).taggings.count
-    posts(:welcome).taggings.first.update_columns taggable_type: 'PostWithHasManyNullify'
+    posts(:welcome).taggings.first.update_columns taggable_type: "PostWithHasManyNullify"
     post = find_post_with_dependency(1, :has_many, :taggings, :nullify)
 
     old_count = Tagging.count
@@ -207,19 +209,19 @@ class AssociationsJoinModelTest < ActiveRecord::TestCase
 
   def test_delete_polymorphic_has_one_with_destroy
     assert posts(:welcome).tagging
-    posts(:welcome).tagging.update_columns taggable_type: 'PostWithHasOneDestroy'
+    posts(:welcome).tagging.update_columns taggable_type: "PostWithHasOneDestroy"
     post = find_post_with_dependency(1, :has_one, :tagging, :destroy)
 
     old_count = Tagging.count
     post.destroy
-    assert_equal old_count-1, Tagging.count
+    assert_equal old_count - 1, Tagging.count
     posts(:welcome).association(:tagging).reload
     assert_nil posts(:welcome).tagging
   end
 
   def test_delete_polymorphic_has_one_with_nullify
     assert posts(:welcome).tagging
-    posts(:welcome).tagging.update_columns taggable_type: 'PostWithHasOneNullify'
+    posts(:welcome).tagging.update_columns taggable_type: "PostWithHasOneNullify"
     post = find_post_with_dependency(1, :has_one, :tagging, :nullify)
 
     old_count = Tagging.count
@@ -235,15 +237,15 @@ class AssociationsJoinModelTest < ActiveRecord::TestCase
 
   def test_create_through_has_many_with_piggyback
     category = categories(:sti_test)
-    ernie = category.authors_with_select.create(:name => 'Ernie')
+    ernie = category.authors_with_select.create(name: "Ernie")
     assert_nothing_raised do
-      assert_equal ernie, category.authors_with_select.detect {|a| a.name == 'Ernie'}
+      assert_equal ernie, category.authors_with_select.detect { |a| a.name == "Ernie" }
     end
   end
 
   def test_include_has_many_through
-    posts              = Post.all.merge!(:order => 'posts.id').to_a
-    posts_with_authors = Post.all.merge!(:includes => :authors, :order => 'posts.id').to_a
+    posts              = Post.all.merge!(order: "posts.id").to_a
+    posts_with_authors = Post.all.merge!(includes: :authors, order: "posts.id").to_a
     assert_equal posts.length, posts_with_authors.length
     posts.length.times do |i|
       assert_equal posts[i].authors.length, assert_no_queries { posts_with_authors[i].authors.length }
@@ -267,8 +269,8 @@ class AssociationsJoinModelTest < ActiveRecord::TestCase
   end
 
   def test_include_polymorphic_has_many_through
-    posts           = Post.all.merge!(:order => 'posts.id').to_a
-    posts_with_tags = Post.all.merge!(:includes => :tags, :order => 'posts.id').to_a
+    posts           = Post.all.merge!(order: "posts.id").to_a
+    posts_with_tags = Post.all.merge!(includes: :tags, order: "posts.id").to_a
     assert_equal posts.length, posts_with_tags.length
     posts.length.times do |i|
       assert_equal posts[i].tags.length, assert_no_queries { posts_with_tags[i].tags.length }
@@ -276,8 +278,8 @@ class AssociationsJoinModelTest < ActiveRecord::TestCase
   end
 
   def test_include_polymorphic_has_many
-    posts               = Post.all.merge!(:order => 'posts.id').to_a
-    posts_with_taggings = Post.all.merge!(:includes => :taggings, :order => 'posts.id').to_a
+    posts               = Post.all.merge!(order: "posts.id").to_a
+    posts_with_taggings = Post.all.merge!(includes: :taggings, order: "posts.id").to_a
     assert_equal posts.length, posts_with_taggings.length
     posts.length.times do |i|
       assert_equal posts[i].taggings.length, assert_no_queries { posts_with_taggings[i].taggings.length }
@@ -302,7 +304,7 @@ class AssociationsJoinModelTest < ActiveRecord::TestCase
   end
 
   def test_has_many_array_methods_called_by_method_missing
-    assert authors(:david).categories.any? { |category| category.name == 'General' }
+    assert authors(:david).categories.any? { |category| category.name == "General" }
     assert_nothing_raised { authors(:david).categories.sort }
   end
 
@@ -324,12 +326,12 @@ class AssociationsJoinModelTest < ActiveRecord::TestCase
   end
 
   def test_has_many_through_with_custom_primary_key_on_has_many_source
-    assert_equal [authors(:david), authors(:bob)], posts(:thinking).authors_using_custom_pk.order('authors.id')
+    assert_equal [authors(:david), authors(:bob)], posts(:thinking).authors_using_custom_pk.order("authors.id")
   end
 
   def test_belongs_to_polymorphic_with_counter_cache
     assert_equal 1, posts(:welcome)[:tags_count]
-    tagging = posts(:welcome).taggings.create(:tag => tags(:general))
+    tagging = posts(:welcome).taggings.create(tag: tags(:general))
     assert_equal 2, posts(:welcome, :reload)[:tags_count]
     tagging.destroy
     assert_equal 1, posts(:welcome, :reload)[:tags_count]
@@ -354,7 +356,7 @@ class AssociationsJoinModelTest < ActiveRecord::TestCase
     end
 
     assert_raise ActiveRecord::EagerLoadPolymorphicError do
-      tags(:general).taggings.includes(:taggable).where('bogus_table.column = 1').references(:bogus_table).to_a
+      tags(:general).taggings.includes(:taggable).where("bogus_table.column = 1").references(:bogus_table).to_a
     end
   end
 
@@ -365,13 +367,13 @@ class AssociationsJoinModelTest < ActiveRecord::TestCase
 
   def test_has_many_polymorphic_associations_merges_through_scope
     Tag.has_many :null_taggings, -> { none }, class_name: :Tagging
-    Tag.has_many :null_tagged_posts, :through => :null_taggings, :source => 'taggable', :source_type => 'Post'
+    Tag.has_many :null_tagged_posts, through: :null_taggings, source: "taggable", source_type: "Post"
     assert_equal [], tags(:general).null_tagged_posts
     refute_equal [], tags(:general).tagged_posts
   end
 
   def test_eager_has_many_polymorphic_with_source_type
-    tag_with_include = Tag.all.merge!(:includes => :tagged_posts).find(tags(:general).id)
+    tag_with_include = Tag.all.merge!(includes: :tagged_posts).find(tags(:general).id)
     desired = posts(:welcome, :thinking)
     assert_no_queries do
       # added sort by ID as otherwise test using JRuby was failing as array elements were in different order
@@ -381,19 +383,19 @@ class AssociationsJoinModelTest < ActiveRecord::TestCase
   end
 
   def test_has_many_through_has_many_find_all
-    assert_equal comments(:greetings), authors(:david).comments.order('comments.id').to_a.first
+    assert_equal comments(:greetings), authors(:david).comments.order("comments.id").to_a.first
   end
 
   def test_has_many_through_has_many_find_all_with_custom_class
-    assert_equal comments(:greetings), authors(:david).funky_comments.order('comments.id').to_a.first
+    assert_equal comments(:greetings), authors(:david).funky_comments.order("comments.id").to_a.first
   end
 
   def test_has_many_through_has_many_find_first
-    assert_equal comments(:greetings), authors(:david).comments.order('comments.id').first
+    assert_equal comments(:greetings), authors(:david).comments.order("comments.id").first
   end
 
   def test_has_many_through_has_many_find_conditions
-    options = { :where => "comments.#{QUOTED_TYPE}='SpecialComment'", :order => 'comments.id' }
+    options = { where: "comments.#{QUOTED_TYPE}='SpecialComment'", order: "comments.id" }
     assert_equal comments(:does_it_hurt), authors(:david).comments.merge(options).first
   end
 
@@ -402,7 +404,7 @@ class AssociationsJoinModelTest < ActiveRecord::TestCase
   end
 
   def test_has_many_through_polymorphic_has_one
-    assert_equal Tagging.find(1,2).sort_by(&:id), authors(:david).taggings_2
+    assert_equal Tagging.find(1, 2).sort_by(&:id), authors(:david).taggings_2.sort_by(&:id)
   end
 
   def test_has_many_through_polymorphic_has_many
@@ -413,20 +415,20 @@ class AssociationsJoinModelTest < ActiveRecord::TestCase
     author            = Author.includes(:taggings).find authors(:david).id
     expected_taggings = taggings(:welcome_general, :thinking_general)
     assert_no_queries do
-      assert_equal expected_taggings, author.taggings.distinct.sort_by(&:id)
+      assert_equal expected_taggings, author.taggings.uniq.sort_by(&:id)
     end
   end
 
   def test_eager_load_has_many_through_has_many
-    author = Author.all.merge!(:where => ['name = ?', 'David'], :includes => :comments, :order => 'comments.id').first
+    author = Author.all.merge!(where: ["name = ?", "David"], includes: :comments, order: "comments.id").first
     SpecialComment.new; VerySpecialComment.new
     assert_no_queries do
-      assert_equal [1,2,3,5,6,7,8,9,10,12], author.comments.collect(&:id)
+      assert_equal [1, 2, 3, 5, 6, 7, 8, 9, 10, 12], author.comments.collect(&:id)
     end
   end
 
   def test_eager_load_has_many_through_has_many_with_conditions
-    post = Post.all.merge!(:includes => :invalid_tags).first
+    post = Post.all.merge!(includes: :invalid_tags).first
     assert_no_queries do
       post.invalid_tags
     end
@@ -434,8 +436,8 @@ class AssociationsJoinModelTest < ActiveRecord::TestCase
 
   def test_eager_belongs_to_and_has_one_not_singularized
     assert_nothing_raised do
-      Author.all.merge!(:includes => :author_address).first
-      AuthorAddress.all.merge!(:includes => :author).first
+      Author.all.merge!(includes: :author_address).first
+      AuthorAddress.all.merge!(includes: :author).first
     end
   end
 
@@ -445,8 +447,8 @@ class AssociationsJoinModelTest < ActiveRecord::TestCase
   end
 
   def test_add_to_self_referential_has_many_through
-    new_author = Author.create(:name => "Bob")
-    authors(:david).author_favorites.create :favorite_author => new_author
+    new_author = Author.create(name: "Bob")
+    authors(:david).author_favorites.create favorite_author: new_author
     assert_equal new_author, authors(:david).reload.favorite_authors.first
   end
 
@@ -462,28 +464,27 @@ class AssociationsJoinModelTest < ActiveRecord::TestCase
 
   def test_associating_unsaved_records_with_has_many_through
     saved_post = posts(:thinking)
-    new_tag = Tag.new(:name => "new")
+    new_tag = Tag.new(name: "new")
 
     saved_post.tags << new_tag
-    assert new_tag.persisted? #consistent with habtm!
+    assert new_tag.persisted? # consistent with habtm!
     assert saved_post.persisted?
-    assert saved_post.tags.include?(new_tag)
+    assert_includes saved_post.tags, new_tag
 
     assert new_tag.persisted?
-    assert saved_post.reload.tags.reload.include?(new_tag)
-
+    assert_includes saved_post.reload.tags.reload, new_tag
 
-    new_post = Post.new(:title => "Association replacement works!", :body => "You best believe it.")
+    new_post = Post.new(title: "Association replacement works!", body: "You best believe it.")
     saved_tag = tags(:general)
 
     new_post.tags << saved_tag
     assert !new_post.persisted?
     assert saved_tag.persisted?
-    assert new_post.tags.include?(saved_tag)
+    assert_includes new_post.tags, saved_tag
 
     new_post.save!
     assert new_post.persisted?
-    assert new_post.reload.tags.reload.include?(saved_tag)
+    assert_includes new_post.reload.tags.reload, saved_tag
 
     assert !posts(:thinking).tags.build.persisted?
     assert !posts(:thinking).tags.new.persisted?
@@ -491,29 +492,29 @@ class AssociationsJoinModelTest < ActiveRecord::TestCase
 
   def test_create_associate_when_adding_to_has_many_through
     count = posts(:thinking).tags.count
-    push = Tag.create!(:name => 'pushme')
+    push = Tag.create!(name: "pushme")
     post_thinking = posts(:thinking)
     assert_nothing_raised { post_thinking.tags << push }
-    assert_nil( wrong = post_thinking.tags.detect { |t| t.class != Tag },
-                message = "Expected a Tag in tags collection, got #{wrong.class}.")
-    assert_nil( wrong = post_thinking.taggings.detect { |t| t.class != Tagging },
-                message = "Expected a Tagging in taggings collection, got #{wrong.class}.")
+    assert_nil(wrong = post_thinking.tags.detect { |t| t.class != Tag },
+               "Expected a Tag in tags collection, got #{wrong.class}.")
+    assert_nil(wrong = post_thinking.taggings.detect { |t| t.class != Tagging },
+               "Expected a Tagging in taggings collection, got #{wrong.class}.")
     assert_equal(count + 1, post_thinking.reload.tags.size)
     assert_equal(count + 1, post_thinking.tags.reload.size)
 
-    assert_kind_of Tag, post_thinking.tags.create!(:name => 'foo')
-    assert_nil( wrong = post_thinking.tags.detect { |t| t.class != Tag },
-                message = "Expected a Tag in tags collection, got #{wrong.class}.")
-    assert_nil( wrong = post_thinking.taggings.detect { |t| t.class != Tagging },
-                message = "Expected a Tagging in taggings collection, got #{wrong.class}.")
+    assert_kind_of Tag, post_thinking.tags.create!(name: "foo")
+    assert_nil(wrong = post_thinking.tags.detect { |t| t.class != Tag },
+               "Expected a Tag in tags collection, got #{wrong.class}.")
+    assert_nil(wrong = post_thinking.taggings.detect { |t| t.class != Tagging },
+               "Expected a Tagging in taggings collection, got #{wrong.class}.")
     assert_equal(count + 2, post_thinking.reload.tags.size)
     assert_equal(count + 2, post_thinking.tags.reload.size)
 
-    assert_nothing_raised { post_thinking.tags.concat(Tag.create!(:name => 'abc'), Tag.create!(:name => 'def')) }
-    assert_nil( wrong = post_thinking.tags.detect { |t| t.class != Tag },
-                message = "Expected a Tag in tags collection, got #{wrong.class}.")
-    assert_nil( wrong = post_thinking.taggings.detect { |t| t.class != Tagging },
-                message = "Expected a Tagging in taggings collection, got #{wrong.class}.")
+    assert_nothing_raised { post_thinking.tags.concat(Tag.create!(name: "abc"), Tag.create!(name: "def")) }
+    assert_nil(wrong = post_thinking.tags.detect { |t| t.class != Tag },
+               "Expected a Tag in tags collection, got #{wrong.class}.")
+    assert_nil(wrong = post_thinking.taggings.detect { |t| t.class != Tagging },
+               "Expected a Tagging in taggings collection, got #{wrong.class}.")
     assert_equal(count + 4, post_thinking.reload.tags.size)
     assert_equal(count + 4, post_thinking.tags.reload.size)
 
@@ -550,7 +551,7 @@ class AssociationsJoinModelTest < ActiveRecord::TestCase
   def test_delete_associate_when_deleting_from_has_many_through_with_nonstandard_id
     count = books(:awdr).references.count
     references_before = books(:awdr).references
-    book = Book.create!(:name => 'Getting Real')
+    book = Book.create!(name: "Getting Real")
     book_awdr = books(:awdr)
     book_awdr.references << book
     assert_equal(count + 1, book_awdr.references.reload.size)
@@ -564,7 +565,7 @@ class AssociationsJoinModelTest < ActiveRecord::TestCase
   def test_delete_associate_when_deleting_from_has_many_through
     count = posts(:thinking).tags.count
     tags_before = posts(:thinking).tags.sort
-    tag = Tag.create!(:name => 'doomed')
+    tag = Tag.create!(name: "doomed")
     post_thinking = posts(:thinking)
     post_thinking.tags << tag
     assert_equal(count + 1, post_thinking.taggings.reload.size)
@@ -581,9 +582,9 @@ class AssociationsJoinModelTest < ActiveRecord::TestCase
   def test_delete_associate_when_deleting_from_has_many_through_with_multiple_tags
     count = posts(:thinking).tags.count
     tags_before = posts(:thinking).tags.sort
-    doomed = Tag.create!(:name => 'doomed')
-    doomed2 = Tag.create!(:name => 'doomed2')
-    quaked = Tag.create!(:name => 'quaked')
+    doomed = Tag.create!(name: "doomed")
+    doomed2 = Tag.create!(name: "doomed2")
+    quaked = Tag.create!(name: "quaked")
     post_thinking = posts(:thinking)
     post_thinking.tags << doomed << doomed2
     assert_equal(count + 2, post_thinking.reload.tags.reload.size)
@@ -601,7 +602,7 @@ class AssociationsJoinModelTest < ActiveRecord::TestCase
   def test_deleting_by_integer_id_from_has_many_through
     post = posts(:thinking)
 
-    assert_difference 'post.tags.count', -1 do
+    assert_difference "post.tags.count", -1 do
       assert_equal 1, post.tags.delete(1).size
     end
 
@@ -611,8 +612,8 @@ class AssociationsJoinModelTest < ActiveRecord::TestCase
   def test_deleting_by_string_id_from_has_many_through
     post = posts(:thinking)
 
-    assert_difference 'post.tags.count', -1 do
-      assert_equal 1, post.tags.delete('1').size
+    assert_difference "post.tags.count", -1 do
+      assert_equal 1, post.tags.delete("1").size
     end
 
     assert_equal 0, post.tags.size
@@ -642,26 +643,26 @@ class AssociationsJoinModelTest < ActiveRecord::TestCase
 
   def test_polymorphic_has_many
     expected = taggings(:welcome_general)
-    p = Post.all.merge!(:includes => :taggings).find(posts(:welcome).id)
-    assert_no_queries {assert p.taggings.include?(expected)}
-    assert posts(:welcome).taggings.include?(taggings(:welcome_general))
+    p = Post.all.merge!(includes: :taggings).find(posts(:welcome).id)
+    assert_no_queries { assert_includes p.taggings, expected }
+    assert_includes posts(:welcome).taggings, taggings(:welcome_general)
   end
 
   def test_polymorphic_has_one
     expected = posts(:welcome)
 
-    tagging  = Tagging.all.merge!(:includes => :taggable).find(taggings(:welcome_general).id)
-    assert_no_queries { assert_equal expected, tagging.taggable}
+    tagging  = Tagging.all.merge!(includes: :taggable).find(taggings(:welcome_general).id)
+    assert_no_queries { assert_equal expected, tagging.taggable }
   end
 
   def test_polymorphic_belongs_to
-    p = Post.all.merge!(:includes => {:taggings => :taggable}).find(posts(:welcome).id)
-    assert_no_queries {assert_equal posts(:welcome), p.taggings.first.taggable}
+    p = Post.all.merge!(includes: { taggings: :taggable }).find(posts(:welcome).id)
+    assert_no_queries { assert_equal posts(:welcome), p.taggings.first.taggable }
   end
 
   def test_preload_polymorphic_has_many_through
-    posts           = Post.all.merge!(:order => 'posts.id').to_a
-    posts_with_tags = Post.all.merge!(:includes => :tags, :order => 'posts.id').to_a
+    posts           = Post.all.merge!(order: "posts.id").to_a
+    posts_with_tags = Post.all.merge!(includes: :tags, order: "posts.id").to_a
     assert_equal posts.length, posts_with_tags.length
     posts.length.times do |i|
       assert_equal posts[i].tags.length, assert_no_queries { posts_with_tags[i].tags.length }
@@ -669,26 +670,26 @@ class AssociationsJoinModelTest < ActiveRecord::TestCase
   end
 
   def test_preload_polymorph_many_types
-    taggings = Tagging.all.merge!(:includes => :taggable, :where => ['taggable_type != ?', 'FakeModel']).to_a
+    taggings = Tagging.all.merge!(includes: :taggable, where: ["taggable_type != ?", "FakeModel"]).to_a
     assert_no_queries do
       taggings.first.taggable.id
       taggings[1].taggable.id
     end
 
     taggables = taggings.map(&:taggable)
-    assert taggables.include?(items(:dvd))
-    assert taggables.include?(posts(:welcome))
+    assert_includes taggables, items(:dvd)
+    assert_includes taggables, posts(:welcome)
   end
 
   def test_preload_nil_polymorphic_belongs_to
     assert_nothing_raised do
-      Tagging.all.merge!(:includes => :taggable, :where => ['taggable_type IS NULL']).to_a
+      Tagging.all.merge!(includes: :taggable, where: ["taggable_type IS NULL"]).to_a
     end
   end
 
   def test_preload_polymorphic_has_many
-    posts               = Post.all.merge!(:order => 'posts.id').to_a
-    posts_with_taggings = Post.all.merge!(:includes => :taggings, :order => 'posts.id').to_a
+    posts               = Post.all.merge!(order: "posts.id").to_a
+    posts_with_taggings = Post.all.merge!(includes: :taggings, order: "posts.id").to_a
     assert_equal posts.length, posts_with_taggings.length
     posts.length.times do |i|
       assert_equal posts[i].taggings.length, assert_no_queries { posts_with_taggings[i].taggings.length }
@@ -696,7 +697,7 @@ class AssociationsJoinModelTest < ActiveRecord::TestCase
   end
 
   def test_belongs_to_shared_parent
-    comments = Comment.all.merge!(:includes => :post, :where => 'post_id = 1').to_a
+    comments = Comment.all.merge!(includes: :post, where: "post_id = 1").to_a
     assert_no_queries do
       assert_equal comments.first.post, comments[1].post
     end
@@ -710,7 +711,7 @@ class AssociationsJoinModelTest < ActiveRecord::TestCase
 
     assert_no_queries do
       assert david.categories.loaded?
-      assert david.categories.include?(category)
+      assert_includes david.categories, category
     end
   end
 
@@ -721,45 +722,45 @@ class AssociationsJoinModelTest < ActiveRecord::TestCase
     david.reload
     assert ! david.categories.loaded?
     assert_queries(1) do
-      assert david.categories.include?(category)
+      assert_includes david.categories, category
     end
     assert ! david.categories.loaded?
   end
 
   def test_has_many_through_include_returns_false_for_non_matching_record_to_verify_scoping
     david = authors(:david)
-    category = Category.create!(:name => 'Not Associated')
+    category = Category.create!(name: "Not Associated")
 
     assert ! david.categories.loaded?
     assert ! david.categories.include?(category)
   end
 
   def test_has_many_through_goes_through_all_sti_classes
-    sub_sti_post = SubStiPost.create!(:title => 'test', :body => 'test', :author_id => 1)
-    new_comment = sub_sti_post.comments.create(:body => 'test')
+    sub_sti_post = SubStiPost.create!(title: "test", body: "test", author_id: 1)
+    new_comment = sub_sti_post.comments.create(body: "test")
 
     assert_equal [9, 10, new_comment.id], authors(:david).sti_post_comments.map(&:id).sort
   end
 
   def test_has_many_with_pluralize_table_names_false
-    aircraft = Aircraft.create!(:name => "Airbus 380")
-    engine = Engine.create!(:car_id => aircraft.id)
+    aircraft = Aircraft.create!(name: "Airbus 380")
+    engine = Engine.create!(car_id: aircraft.id)
     assert_equal aircraft.engines, [engine]
   end
 
   def test_proper_error_message_for_eager_load_and_includes_association_errors
     includes_error = assert_raises(ActiveRecord::ConfigurationError) {
-      Post.includes(:nonexistent_relation).where(nonexistent_relation: {name: 'Rochester'}).find(1)
+      Post.includes(:nonexistent_relation).where(nonexistent_relation: { name: "Rochester" }).find(1)
     }
     assert_equal("Can't join 'Post' to association named 'nonexistent_relation'; perhaps you misspelled it?", includes_error.message)
 
     eager_load_error = assert_raises(ActiveRecord::ConfigurationError) {
-      Post.eager_load(:nonexistent_relation).where(nonexistent_relation: {name: 'Rochester'}).find(1)
+      Post.eager_load(:nonexistent_relation).where(nonexistent_relation: { name: "Rochester" }).find(1)
     }
     assert_equal("Can't join 'Post' to association named 'nonexistent_relation'; perhaps you misspelled it?", eager_load_error.message)
 
     includes_and_eager_load_error = assert_raises(ActiveRecord::ConfigurationError) {
-      Post.eager_load(:nonexistent_relation).includes(:nonexistent_relation).where(nonexistent_relation: {name: 'Rochester'}).find(1)
+      Post.eager_load(:nonexistent_relation).includes(:nonexistent_relation).where(nonexistent_relation: { name: "Rochester" }).find(1)
     }
     assert_equal("Can't join 'Post' to association named 'nonexistent_relation'; perhaps you misspelled it?", includes_and_eager_load_error.message)
   end
@@ -770,8 +771,8 @@ class AssociationsJoinModelTest < ActiveRecord::TestCase
       class_name = "PostWith#{association.to_s.classify}#{dependency.to_s.classify}"
       Post.find(post_id).update_columns type: class_name
       klass = Object.const_set(class_name, Class.new(ActiveRecord::Base))
-      klass.table_name = 'posts'
-      klass.send(association, association_name, :as => :taggable, :dependent => dependency)
+      klass.table_name = "posts"
+      klass.send(association, association_name, as: :taggable, dependent: dependency)
       klass.find(post_id)
     end
 end
diff --git a/activerecord/test/cases/associations/left_outer_join_association_test.rb b/activerecord/test/cases/associations/left_outer_join_association_test.rb
index eee135cfb8..c95d0425cd 100644
--- a/activerecord/test/cases/associations/left_outer_join_association_test.rb
+++ b/activerecord/test/cases/associations/left_outer_join_association_test.rb
@@ -1,13 +1,15 @@
+# frozen_string_literal: true
+
 require "cases/helper"
-require 'models/post'
-require 'models/comment'
-require 'models/author'
-require 'models/essay'
-require 'models/categorization'
-require 'models/person'
+require "models/post"
+require "models/comment"
+require "models/author"
+require "models/essay"
+require "models/categorization"
+require "models/person"
 
 class LeftOuterJoinAssociationTest < ActiveRecord::TestCase
-  fixtures :authors, :essays, :posts, :comments, :categorizations, :people
+  fixtures :authors, :author_addresses, :essays, :posts, :comments, :categorizations, :people
 
   def test_construct_finder_sql_applies_aliases_tables_on_association_conditions
     result = Author.left_outer_joins(:thinking_posts, :welcome_posts).to_a
@@ -17,45 +19,54 @@ class LeftOuterJoinAssociationTest < ActiveRecord::TestCase
   def test_construct_finder_sql_does_not_table_name_collide_on_duplicate_associations
     assert_nothing_raised do
       queries = capture_sql do
-        Person.left_outer_joins(:agents => {:agents => :agents})
-              .left_outer_joins(:agents => {:agents => {:primary_contact => :agents}}).to_a
+        Person.left_outer_joins(agents: { agents: :agents })
+              .left_outer_joins(agents: { agents: { primary_contact: :agents } }).to_a
       end
-      assert queries.any? { |sql| /agents_people_4/i =~ sql }
+      assert queries.any? { |sql| /agents_people_4/i.match?(sql) }
     end
   end
 
-  def test_construct_finder_sql_executes_a_left_outer_join
-    assert_not_equal Author.count, Author.joins(:posts).count
-    assert_equal Author.count, Author.left_outer_joins(:posts).count
+  def test_left_outer_joins_count_is_same_as_size_of_loaded_results
+    assert_equal 17, Post.left_outer_joins(:comments).to_a.size
+    assert_equal 17, Post.left_outer_joins(:comments).count
+  end
+
+  def test_left_joins_aliases_left_outer_joins
+    assert_equal Post.left_outer_joins(:comments).to_sql, Post.left_joins(:comments).to_sql
+  end
+
+  def test_left_outer_joins_return_has_value_for_every_comment
+    all_post_ids = Post.pluck(:id)
+    assert_equal all_post_ids, all_post_ids & Post.left_outer_joins(:comments).pluck(:id)
   end
 
-  def test_left_outer_join_by_left_joins
-    assert_not_equal Author.count, Author.joins(:posts).count
-    assert_equal Author.count, Author.left_joins(:posts).count
+  def test_left_outer_joins_actually_does_a_left_outer_join
+    queries = capture_sql { Author.left_outer_joins(:posts).to_a }
+    assert queries.any? { |sql| /LEFT OUTER JOIN/i.match?(sql) }
   end
 
   def test_construct_finder_sql_ignores_empty_left_outer_joins_hash
-    queries = capture_sql { Author.left_outer_joins({}) }
-    assert queries.none? { |sql| /LEFT OUTER JOIN/i =~ sql }
+    queries = capture_sql { Author.left_outer_joins({}).to_a }
+    assert queries.none? { |sql| /LEFT OUTER JOIN/i.match?(sql) }
   end
 
   def test_construct_finder_sql_ignores_empty_left_outer_joins_array
-    queries = capture_sql { Author.left_outer_joins([]) }
-    assert queries.none? { |sql| /LEFT OUTER JOIN/i =~ sql }
+    queries = capture_sql { Author.left_outer_joins([]).to_a }
+    assert queries.none? { |sql| /LEFT OUTER JOIN/i.match?(sql) }
   end
 
   def test_left_outer_joins_forbids_to_use_string_as_argument
-    assert_raise(ArgumentError){ Author.left_outer_joins('LEFT OUTER JOIN "posts" ON "posts"."user_id" = "users"."id"').to_a }
+    assert_raise(ArgumentError) { Author.left_outer_joins('LEFT OUTER JOIN "posts" ON "posts"."user_id" = "users"."id"').to_a }
   end
 
   def test_join_conditions_added_to_join_clause
     queries = capture_sql { Author.left_outer_joins(:essays).to_a }
-    assert queries.any? { |sql| /writer_type.*?=.*?(Author|\?|\$1|\:a1)/i =~ sql }
-    assert queries.none? { |sql| /WHERE/i =~ sql }
+    assert queries.any? { |sql| /writer_type.*?=.*?(Author|\?|\$1|\:a1)/i.match?(sql) }
+    assert queries.none? { |sql| /WHERE/i.match?(sql) }
   end
 
   def test_find_with_sti_join
-    scope = Post.left_outer_joins(:special_comments).where(:id => posts(:sti_comments).id)
+    scope = Post.left_outer_joins(:special_comments).where(id: posts(:sti_comments).id)
 
     # The join should match SpecialComment and its subclasses only
     assert scope.where("comments.type" => "Comment").empty?
diff --git a/activerecord/test/cases/associations/nested_through_associations_test.rb b/activerecord/test/cases/associations/nested_through_associations_test.rb
index b040485d99..65d30d011b 100644
--- a/activerecord/test/cases/associations/nested_through_associations_test.rb
+++ b/activerecord/test/cases/associations/nested_through_associations_test.rb
@@ -1,30 +1,37 @@
+# frozen_string_literal: true
+
 require "cases/helper"
-require 'models/author'
-require 'models/post'
-require 'models/person'
-require 'models/reference'
-require 'models/job'
-require 'models/reader'
-require 'models/comment'
-require 'models/tag'
-require 'models/tagging'
-require 'models/subscriber'
-require 'models/book'
-require 'models/subscription'
-require 'models/rating'
-require 'models/member'
-require 'models/member_detail'
-require 'models/member_type'
-require 'models/sponsor'
-require 'models/club'
-require 'models/organization'
-require 'models/category'
-require 'models/categorization'
-require 'models/membership'
-require 'models/essay'
+require "models/author"
+require "models/post"
+require "models/person"
+require "models/reference"
+require "models/job"
+require "models/reader"
+require "models/comment"
+require "models/tag"
+require "models/tagging"
+require "models/subscriber"
+require "models/book"
+require "models/subscription"
+require "models/rating"
+require "models/member"
+require "models/member_detail"
+require "models/member_type"
+require "models/sponsor"
+require "models/club"
+require "models/organization"
+require "models/category"
+require "models/categorization"
+require "models/membership"
+require "models/essay"
+require "models/hotel"
+require "models/department"
+require "models/chef"
+require "models/cake_designer"
+require "models/drink_designer"
 
 class NestedThroughAssociationsTest < ActiveRecord::TestCase
-  fixtures :authors, :books, :posts, :subscriptions, :subscribers, :tags, :taggings,
+  fixtures :authors, :author_addresses, :books, :posts, :subscriptions, :subscribers, :tags, :taggings,
            :people, :readers, :references, :jobs, :ratings, :comments, :members, :member_details,
            :member_types, :sponsors, :clubs, :organizations, :categories, :categories_posts,
            :categorizations, :memberships, :essays
@@ -65,12 +72,12 @@ class NestedThroughAssociationsTest < ActiveRecord::TestCase
 
   def test_has_many_through_has_many_with_has_many_through_source_reflection_preload_via_joins
     assert_includes_and_joins_equal(
-      Author.where('tags.id' => tags(:general).id),
+      Author.where("tags.id" => tags(:general).id),
       [authors(:david)], :tags
     )
 
     # This ensures that the polymorphism of taggings is being observed correctly
-    authors = Author.joins(:tags).where('taggings.taggable_type' => 'FakeModel')
+    authors = Author.joins(:tags).where("taggings.taggable_type" => "FakeModel")
     assert authors.empty?
   end
 
@@ -79,7 +86,7 @@ class NestedThroughAssociationsTest < ActiveRecord::TestCase
   # Through: has_many through
   def test_has_many_through_has_many_through_with_has_many_source_reflection
     luke, david = subscribers(:first), subscribers(:second)
-    assert_equal [luke, david, david], authors(:david).subscribers.order('subscribers.nick')
+    assert_equal [luke, david, david], authors(:david).subscribers.order("subscribers.nick")
   end
 
   def test_has_many_through_has_many_through_with_has_many_source_reflection_preload
@@ -93,7 +100,7 @@ class NestedThroughAssociationsTest < ActiveRecord::TestCase
   def test_has_many_through_has_many_through_with_has_many_source_reflection_preload_via_joins
     # All authors with subscribers where one of the subscribers' nick is 'alterself'
     assert_includes_and_joins_equal(
-      Author.where('subscribers.nick' => 'alterself'),
+      Author.where("subscribers.nick" => "alterself"),
       [authors(:david)], :subscribers
     )
   end
@@ -115,7 +122,7 @@ class NestedThroughAssociationsTest < ActiveRecord::TestCase
 
   def test_has_many_through_has_one_with_has_one_through_source_reflection_preload_via_joins
     assert_includes_and_joins_equal(
-      Member.where('member_types.id' => member_types(:founding).id),
+      Member.where("member_types.id" => member_types(:founding).id),
       [members(:groucho)], :nested_member_types
     )
   end
@@ -137,7 +144,7 @@ class NestedThroughAssociationsTest < ActiveRecord::TestCase
 
   def test_has_many_through_has_one_through_with_has_one_source_reflection_preload_via_joins
     assert_includes_and_joins_equal(
-      Member.where('sponsors.id' => sponsors(:moustache_club_sponsor_for_groucho).id),
+      Member.where("sponsors.id" => sponsors(:moustache_club_sponsor_for_groucho).id),
       [members(:groucho)], :nested_sponsors
     )
   end
@@ -149,7 +156,7 @@ class NestedThroughAssociationsTest < ActiveRecord::TestCase
     groucho_details, other_details = member_details(:groucho), member_details(:some_other_guy)
 
     assert_equal [groucho_details, other_details],
-                 members(:groucho).organization_member_details.order('member_details.id')
+                 members(:groucho).organization_member_details.order("member_details.id")
   end
 
   def test_has_many_through_has_one_with_has_many_through_source_reflection_preload
@@ -164,12 +171,12 @@ class NestedThroughAssociationsTest < ActiveRecord::TestCase
 
   def test_has_many_through_has_one_with_has_many_through_source_reflection_preload_via_joins
     assert_includes_and_joins_equal(
-      Member.where('member_details.id' => member_details(:groucho).id).order('member_details.id'),
+      Member.where("member_details.id" => member_details(:groucho).id).order("member_details.id"),
       [members(:groucho), members(:some_other_guy)], :organization_member_details
     )
 
     members = Member.joins(:organization_member_details).
-                     where('member_details.id' => 9)
+                     where("member_details.id" => 9)
     assert members.empty?
   end
 
@@ -180,7 +187,7 @@ class NestedThroughAssociationsTest < ActiveRecord::TestCase
     groucho_details, other_details = member_details(:groucho), member_details(:some_other_guy)
 
     assert_equal [groucho_details, other_details],
-                 members(:groucho).organization_member_details_2.order('member_details.id')
+                 members(:groucho).organization_member_details_2.order("member_details.id")
   end
 
   def test_has_many_through_has_one_through_with_has_many_source_reflection_preload
@@ -196,12 +203,12 @@ class NestedThroughAssociationsTest < ActiveRecord::TestCase
 
   def test_has_many_through_has_one_through_with_has_many_source_reflection_preload_via_joins
     assert_includes_and_joins_equal(
-      Member.where('member_details.id' => member_details(:groucho).id).order('member_details.id'),
+      Member.where("member_details.id" => member_details(:groucho).id).order("member_details.id"),
       [members(:groucho), members(:some_other_guy)], :organization_member_details_2
     )
 
     members = Member.joins(:organization_member_details_2).
-                     where('member_details.id' => 9)
+                     where("member_details.id" => 9)
     assert members.empty?
   end
 
@@ -211,7 +218,7 @@ class NestedThroughAssociationsTest < ActiveRecord::TestCase
   def test_has_many_through_has_many_with_has_and_belongs_to_many_source_reflection
     general, cooking = categories(:general), categories(:cooking)
 
-    assert_equal [general, cooking], authors(:bob).post_categories.order('categories.id')
+    assert_equal [general, cooking], authors(:bob).post_categories.order("categories.id")
   end
 
   def test_has_many_through_has_many_with_has_and_belongs_to_many_source_reflection_preload
@@ -228,7 +235,7 @@ class NestedThroughAssociationsTest < ActiveRecord::TestCase
     Author.joins(:post_categories).first
 
     assert_includes_and_joins_equal(
-      Author.where('categories.id' => categories(:cooking).id),
+      Author.where("categories.id" => categories(:cooking).id),
       [authors(:bob)], :post_categories
     )
   end
@@ -239,7 +246,7 @@ class NestedThroughAssociationsTest < ActiveRecord::TestCase
   def test_has_many_through_has_and_belongs_to_many_with_has_many_source_reflection
     greetings, more = comments(:greetings), comments(:more_greetings)
 
-    assert_equal [greetings, more], categories(:technology).post_comments.order('comments.id')
+    assert_equal [greetings, more], categories(:technology).post_comments.order("comments.id")
   end
 
   def test_has_many_through_has_and_belongs_to_many_with_has_many_source_reflection_preload
@@ -257,7 +264,7 @@ class NestedThroughAssociationsTest < ActiveRecord::TestCase
     Category.joins(:post_comments).first
 
     assert_includes_and_joins_equal(
-      Category.where('comments.id' => comments(:more_greetings).id).order('categories.id'),
+      Category.where("comments.id" => comments(:more_greetings).id).order("categories.id"),
       [categories(:general), categories(:technology)], :post_comments
     )
   end
@@ -268,7 +275,7 @@ class NestedThroughAssociationsTest < ActiveRecord::TestCase
   def test_has_many_through_has_many_with_has_many_through_habtm_source_reflection
     greetings, more = comments(:greetings), comments(:more_greetings)
 
-    assert_equal [greetings, more], authors(:bob).category_post_comments.order('comments.id')
+    assert_equal [greetings, more], authors(:bob).category_post_comments.order("comments.id")
   end
 
   def test_has_many_through_has_many_with_has_many_through_habtm_source_reflection_preload
@@ -285,7 +292,7 @@ class NestedThroughAssociationsTest < ActiveRecord::TestCase
     Author.joins(:category_post_comments).first
 
     assert_includes_and_joins_equal(
-      Author.where('comments.id' => comments(:does_it_hurt).id).order('authors.id'),
+      Author.where("comments.id" => comments(:does_it_hurt).id).order("authors.id"),
       [authors(:david), authors(:mary)], :category_post_comments
     )
   end
@@ -308,7 +315,7 @@ class NestedThroughAssociationsTest < ActiveRecord::TestCase
 
   def test_has_many_through_has_many_through_with_belongs_to_source_reflection_preload_via_joins
     assert_includes_and_joins_equal(
-      Author.where('tags.id' => tags(:general).id),
+      Author.where("tags.id" => tags(:general).id),
       [authors(:david)], :tagging_tags
     )
   end
@@ -320,7 +327,7 @@ class NestedThroughAssociationsTest < ActiveRecord::TestCase
     welcome_general, thinking_general = taggings(:welcome_general), taggings(:thinking_general)
 
     assert_equal [welcome_general, thinking_general],
-                 categorizations(:david_welcome_general).post_taggings.order('taggings.id')
+                 categorizations(:david_welcome_general).post_taggings.order("taggings.id")
   end
 
   def test_has_many_through_belongs_to_with_has_many_through_source_reflection_preload
@@ -334,7 +341,7 @@ class NestedThroughAssociationsTest < ActiveRecord::TestCase
 
   def test_has_many_through_belongs_to_with_has_many_through_source_reflection_preload_via_joins
     assert_includes_and_joins_equal(
-      Categorization.where('taggings.id' => taggings(:welcome_general).id).order('taggings.id'),
+      Categorization.where("taggings.id" => taggings(:welcome_general).id).order("taggings.id"),
       [categorizations(:david_welcome_general)], :post_taggings
     )
   end
@@ -357,7 +364,7 @@ class NestedThroughAssociationsTest < ActiveRecord::TestCase
 
   def test_has_one_through_has_one_with_has_one_through_source_reflection_preload_via_joins
     assert_includes_and_joins_equal(
-      Member.where('member_types.id' => member_types(:founding).id),
+      Member.where("member_types.id" => member_types(:founding).id),
       [members(:groucho)], :nested_member_type
     )
   end
@@ -391,7 +398,7 @@ class NestedThroughAssociationsTest < ActiveRecord::TestCase
 
   def test_has_one_through_has_one_through_with_belongs_to_source_reflection_preload_via_joins
     assert_includes_and_joins_equal(
-      Member.where('categories.id' => categories(:technology).id),
+      Member.where("categories.id" => categories(:technology).id),
       [members(:blarpy_winkup)], :club_category
     )
   end
@@ -404,7 +411,7 @@ class NestedThroughAssociationsTest < ActiveRecord::TestCase
   def test_distinct_has_many_through_a_has_many_through_association_on_through_reflection
     author = authors(:david)
     assert_equal [subscribers(:first), subscribers(:second)],
-                 author.distinct_subscribers.order('subscribers.nick')
+                 author.distinct_subscribers.order("subscribers.nick")
   end
 
   def test_nested_has_many_through_with_a_table_referenced_multiple_times
@@ -413,26 +420,31 @@ class NestedThroughAssociationsTest < ActiveRecord::TestCase
                  author.similar_posts.sort_by(&:id)
 
     # Mary and Bob both have posts in misc, but they are the only ones.
-    authors = Author.joins(:similar_posts).where('posts.id' => posts(:misc_by_bob).id)
+    authors = Author.joins(:similar_posts).where("posts.id" => posts(:misc_by_bob).id)
     assert_equal [authors(:mary), authors(:bob)], authors.distinct.sort_by(&:id)
 
     # Check the polymorphism of taggings is being observed correctly (in both joins)
-    authors = Author.joins(:similar_posts).where('taggings.taggable_type' => 'FakeModel')
+    authors = Author.joins(:similar_posts).where("taggings.taggable_type" => "FakeModel")
     assert authors.empty?
-    authors = Author.joins(:similar_posts).where('taggings_authors_join.taggable_type' => 'FakeModel')
+    authors = Author.joins(:similar_posts).where("taggings_authors_join.taggable_type" => "FakeModel")
     assert authors.empty?
   end
 
+  def test_nested_has_many_through_with_scope_on_polymorphic_reflection
+    authors = Author.joins(:ordered_posts).where("posts.id" => posts(:misc_by_bob).id)
+    assert_equal [authors(:mary), authors(:bob)], authors.distinct.sort_by(&:id)
+  end
+
   def test_has_many_through_with_foreign_key_option_on_through_reflection
-    assert_equal [posts(:welcome), posts(:authorless)], people(:david).agents_posts.order('posts.id')
+    assert_equal [posts(:welcome), posts(:authorless)], people(:david).agents_posts.order("posts.id")
     assert_equal [authors(:david)], references(:david_unicyclist).agents_posts_authors
 
-    references = Reference.joins(:agents_posts_authors).where('authors.id' => authors(:david).id)
+    references = Reference.joins(:agents_posts_authors).where("authors.id" => authors(:david).id)
     assert_equal [references(:david_unicyclist)], references
   end
 
   def test_has_many_through_with_foreign_key_option_on_source_reflection
-    assert_equal [people(:michael), people(:susan)], jobs(:unicyclist).agents.order('people.id')
+    assert_equal [people(:michael), people(:susan)], jobs(:unicyclist).agents.order("people.id")
 
     jobs = Job.joins(:agents)
     assert_equal [jobs(:unicyclist), jobs(:unicyclist)], jobs
@@ -443,7 +455,7 @@ class NestedThroughAssociationsTest < ActiveRecord::TestCase
     assert_equal [ratings(:special_comment_rating), ratings(:sub_special_comment_rating)], ratings
 
     # Ensure STI is respected in the join
-    scope = Post.joins(:special_comments_ratings).where(:id => posts(:sti_comments).id)
+    scope = Post.joins(:special_comments_ratings).where(id: posts(:sti_comments).id)
     assert scope.where("comments.type" => "Comment").empty?
     assert !scope.where("comments.type" => "SpecialComment").empty?
     assert !scope.where("comments.type" => "SubSpecialComment").empty?
@@ -453,7 +465,7 @@ class NestedThroughAssociationsTest < ActiveRecord::TestCase
     taggings = posts(:sti_comments).special_comments_ratings_taggings
     assert_equal [taggings(:special_comment_rating)], taggings
 
-    scope = Post.joins(:special_comments_ratings_taggings).where(:id => posts(:sti_comments).id)
+    scope = Post.joins(:special_comments_ratings_taggings).where(id: posts(:sti_comments).id)
     assert scope.where("comments.type" => "Comment").empty?
     assert !scope.where("comments.type" => "SpecialComment").empty?
   end
@@ -505,7 +517,7 @@ class NestedThroughAssociationsTest < ActiveRecord::TestCase
   end
 
   def test_nested_has_many_through_with_conditions_on_through_associations_preload
-    assert Author.where('tags.id' => 100).joins(:misc_post_first_blue_tags).empty?
+    assert Author.where("tags.id" => 100).joins(:misc_post_first_blue_tags).empty?
 
     authors = assert_queries(3) { Author.includes(:misc_post_first_blue_tags).to_a.sort_by(&:id) }
     blue = tags(:blue)
@@ -518,7 +530,7 @@ class NestedThroughAssociationsTest < ActiveRecord::TestCase
   def test_nested_has_many_through_with_conditions_on_through_associations_preload_via_joins
     # Pointless condition to force single-query loading
     assert_includes_and_joins_equal(
-      Author.where('tags.id = tags.id').references(:tags),
+      Author.where("tags.id = tags.id").references(:tags),
       [authors(:bob)], :misc_post_first_blue_tags
     )
   end
@@ -539,7 +551,7 @@ class NestedThroughAssociationsTest < ActiveRecord::TestCase
   def test_nested_has_many_through_with_conditions_on_source_associations_preload_via_joins
     # Pointless condition to force single-query loading
     assert_includes_and_joins_equal(
-      Author.where('tags.id = tags.id').references(:tags),
+      Author.where("tags.id = tags.id").references(:tags),
       [authors(:bob)], :misc_post_first_blue_tags_2
     )
   end
@@ -548,13 +560,13 @@ class NestedThroughAssociationsTest < ActiveRecord::TestCase
     assert_equal [categories(:general)], organizations(:nsa).author_essay_categories
 
     organizations = Organization.joins(:author_essay_categories).
-                                 where('categories.id' => categories(:general).id)
+                                 where("categories.id" => categories(:general).id)
     assert_equal [organizations(:nsa)], organizations
 
     assert_equal categories(:general), organizations(:nsa).author_owned_essay_category
 
     organizations = Organization.joins(:author_owned_essay_category).
-                                 where('categories.id' => categories(:general).id)
+                                 where("categories.id" => categories(:general).id)
     assert_equal [organizations(:nsa)], organizations
   end
 
@@ -567,6 +579,37 @@ class NestedThroughAssociationsTest < ActiveRecord::TestCase
     assert !c.post_taggings.empty?
   end
 
+  def test_polymorphic_has_many_through_when_through_association_has_not_loaded
+    cake_designer = CakeDesigner.create!(chef: Chef.new)
+    drink_designer = DrinkDesigner.create!(chef: Chef.new)
+    department = Department.create!(chefs: [cake_designer.chef, drink_designer.chef])
+    Hotel.create!(departments: [department])
+    hotel = Hotel.includes(:cake_designers, :drink_designers).take
+
+    assert_equal [cake_designer], hotel.cake_designers
+    assert_equal [drink_designer], hotel.drink_designers
+  end
+
+  def test_polymorphic_has_many_through_when_through_association_has_already_loaded
+    cake_designer = CakeDesigner.create!(chef: Chef.new)
+    drink_designer = DrinkDesigner.create!(chef: Chef.new)
+    department = Department.create!(chefs: [cake_designer.chef, drink_designer.chef])
+    Hotel.create!(departments: [department])
+    hotel = Hotel.includes(:chefs, :cake_designers, :drink_designers).take
+
+    assert_equal [cake_designer], hotel.cake_designers
+    assert_equal [drink_designer], hotel.drink_designers
+  end
+
+  def test_polymorphic_has_many_through_joined_different_table_twice
+    cake_designer = CakeDesigner.create!(chef: Chef.new)
+    drink_designer = DrinkDesigner.create!(chef: Chef.new)
+    department = Department.create!(chefs: [cake_designer.chef, drink_designer.chef])
+    hotel = Hotel.create!(departments: [department])
+
+    assert_equal hotel, Hotel.joins(:cake_designers, :drink_designers).take
+  end
+
   private
 
     def assert_includes_and_joins_equal(query, expected, association)
diff --git a/activerecord/test/cases/associations/required_test.rb b/activerecord/test/cases/associations/required_test.rb
index 3e5494e897..65a3bb5efe 100644
--- a/activerecord/test/cases/associations/required_test.rb
+++ b/activerecord/test/cases/associations/required_test.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require "cases/helper"
 
 class RequiredAssociationsTest < ActiveRecord::TestCase
@@ -18,18 +20,25 @@ class RequiredAssociationsTest < ActiveRecord::TestCase
   end
 
   teardown do
-    @connection.drop_table 'parents', if_exists: true
-    @connection.drop_table 'children', if_exists: true
+    @connection.drop_table "parents", if_exists: true
+    @connection.drop_table "children", if_exists: true
   end
 
-  test "belongs_to associations are not required by default" do
-    model = subclass_of(Child) do
-      belongs_to :parent, inverse_of: false,
-        class_name: "RequiredAssociationsTest::Parent"
-    end
+  test "belongs_to associations can be optional by default" do
+    begin
+      original_value = ActiveRecord::Base.belongs_to_required_by_default
+      ActiveRecord::Base.belongs_to_required_by_default = false
 
-    assert model.new.save
-    assert model.new(parent: Parent.new).save
+      model = subclass_of(Child) do
+        belongs_to :parent, inverse_of: false,
+          class_name: "RequiredAssociationsTest::Parent"
+      end
+
+      assert model.new.save
+      assert model.new(parent: Parent.new).save
+    ensure
+      ActiveRecord::Base.belongs_to_required_by_default = original_value
+    end
   end
 
   test "required belongs_to associations have presence validated" do
@@ -46,6 +55,27 @@ class RequiredAssociationsTest < ActiveRecord::TestCase
     assert record.save
   end
 
+  test "belongs_to associations can be required by default" do
+    begin
+      original_value = ActiveRecord::Base.belongs_to_required_by_default
+      ActiveRecord::Base.belongs_to_required_by_default = true
+
+      model = subclass_of(Child) do
+        belongs_to :parent, inverse_of: false,
+          class_name: "RequiredAssociationsTest::Parent"
+      end
+
+      record = model.new
+      assert_not record.save
+      assert_equal ["Parent must exist"], record.errors.full_messages
+
+      record.parent = Parent.new
+      assert record.save
+    ensure
+      ActiveRecord::Base.belongs_to_required_by_default = original_value
+    end
+  end
+
   test "has_one associations are not required by default" do
     model = subclass_of(Parent) do
       has_one :child, inverse_of: false,
@@ -92,11 +122,11 @@ class RequiredAssociationsTest < ActiveRecord::TestCase
 
   private
 
-  def subclass_of(klass, &block)
-    subclass = Class.new(klass, &block)
-    def subclass.name
-      superclass.name
+    def subclass_of(klass, &block)
+      subclass = Class.new(klass, &block)
+      def subclass.name
+        superclass.name
+      end
+      subclass
     end
-    subclass
-  end
 end
diff --git a/activerecord/test/cases/associations_test.rb b/activerecord/test/cases/associations_test.rb
index 01a058918a..de04221ea6 100644
--- a/activerecord/test/cases/associations_test.rb
+++ b/activerecord/test/cases/associations_test.rb
@@ -1,80 +1,79 @@
+# frozen_string_literal: true
+
 require "cases/helper"
-require 'models/computer'
-require 'models/developer'
-require 'models/project'
-require 'models/company'
-require 'models/categorization'
-require 'models/category'
-require 'models/post'
-require 'models/author'
-require 'models/comment'
-require 'models/tag'
-require 'models/tagging'
-require 'models/person'
-require 'models/reader'
-require 'models/ship_part'
-require 'models/ship'
-require 'models/liquid'
-require 'models/molecule'
-require 'models/electron'
-require 'models/man'
-require 'models/interest'
+require "models/computer"
+require "models/developer"
+require "models/project"
+require "models/company"
+require "models/categorization"
+require "models/category"
+require "models/post"
+require "models/author"
+require "models/comment"
+require "models/tag"
+require "models/tagging"
+require "models/person"
+require "models/reader"
+require "models/ship_part"
+require "models/ship"
+require "models/liquid"
+require "models/molecule"
+require "models/electron"
+require "models/man"
+require "models/interest"
 
 class AssociationsTest < ActiveRecord::TestCase
   fixtures :accounts, :companies, :developers, :projects, :developers_projects,
-           :computers, :people, :readers, :authors, :author_favorites
+           :computers, :people, :readers, :authors, :author_addresses, :author_favorites
 
   def test_eager_loading_should_not_change_count_of_children
-    liquid = Liquid.create(:name => 'salty')
-    molecule = liquid.molecules.create(:name => 'molecule_1')
-    molecule.electrons.create(:name => 'electron_1')
-    molecule.electrons.create(:name => 'electron_2')
+    liquid = Liquid.create(name: "salty")
+    molecule = liquid.molecules.create(name: "molecule_1")
+    molecule.electrons.create(name: "electron_1")
+    molecule.electrons.create(name: "electron_2")
 
-    liquids = Liquid.includes(:molecules => :electrons).references(:molecules).where('molecules.id is not null')
+    liquids = Liquid.includes(molecules: :electrons).references(:molecules).where("molecules.id is not null")
     assert_equal 1, liquids[0].molecules.length
   end
 
   def test_subselect
     author = authors :david
     favs = author.author_favorites
-    fav2 = author.author_favorites.where(:author => Author.where(id: author.id)).to_a
+    fav2 = author.author_favorites.where(author: Author.where(id: author.id)).to_a
     assert_equal favs, fav2
   end
 
   def test_loading_the_association_target_should_keep_child_records_marked_for_destruction
-    ship = Ship.create!(:name => "The good ship Dollypop")
-    part = ship.parts.create!(:name => "Mast")
+    ship = Ship.create!(name: "The good ship Dollypop")
+    part = ship.parts.create!(name: "Mast")
     part.mark_for_destruction
-    ship.parts.send(:load_target)
     assert ship.parts[0].marked_for_destruction?
   end
 
   def test_loading_the_association_target_should_load_most_recent_attributes_for_child_records_marked_for_destruction
-    ship = Ship.create!(:name => "The good ship Dollypop")
-    part = ship.parts.create!(:name => "Mast")
+    ship = Ship.create!(name: "The good ship Dollypop")
+    part = ship.parts.create!(name: "Mast")
     part.mark_for_destruction
-    ShipPart.find(part.id).update_columns(name: 'Deck')
-    ship.parts.send(:load_target)
-    assert_equal 'Deck', ship.parts[0].name
+    ShipPart.find(part.id).update_columns(name: "Deck")
+    assert_equal "Deck", ship.parts[0].name
   end
 
-
   def test_include_with_order_works
-    assert_nothing_raised {Account.all.merge!(:order => 'id', :includes => :firm).first}
-    assert_nothing_raised {Account.all.merge!(:order => :id, :includes => :firm).first}
+    assert_nothing_raised { Account.all.merge!(order: "id", includes: :firm).first }
+    assert_nothing_raised { Account.all.merge!(order: :id, includes: :firm).first }
   end
 
   def test_bad_collection_keys
-    assert_raise(ArgumentError, 'ActiveRecord should have barked on bad collection keys') do
-      Class.new(ActiveRecord::Base).has_many(:wheels, :name => 'wheels')
+    assert_raise(ArgumentError, "ActiveRecord should have barked on bad collection keys") do
+      Class.new(ActiveRecord::Base).has_many(:wheels, name: "wheels")
     end
   end
 
   def test_should_construct_new_finder_sql_after_create
-    person = Person.new :first_name => 'clark'
+    person = Person.new first_name: "clark"
     assert_equal [], person.readers.to_a
     person.save!
-    reader = Reader.create! :person => person, :post => Post.new(:title => "foo", :body => "bar")
+    reader = Reader.create! person: person, post: Post.new(title: "foo", body: "bar")
     assert person.readers.find(reader.id)
   end
 
@@ -91,10 +90,10 @@ class AssociationsTest < ActiveRecord::TestCase
     assert firm.clients.empty?, "New firm should have cached no client objects"
     assert_equal 0, firm.clients.size, "New firm should have cached 0 clients count"
 
-    ActiveSupport::Deprecation.silence do
-      assert !firm.clients(true).empty?, "New firm should have reloaded client objects"
-      assert_equal 1, firm.clients(true).size, "New firm should have reloaded clients count"
-    end
+    firm.clients.reload
+
+    assert !firm.clients.empty?, "New firm should have reloaded client objects"
+    assert_equal 1, firm.clients.size, "New firm should have reloaded clients count"
   end
 
   def test_using_limitable_reflections_helper
@@ -107,35 +106,21 @@ class AssociationsTest < ActiveRecord::TestCase
     assert !using_limitable_reflections.call(mixed_reflections), "No collection associations (has many style) should pass"
   end
 
-  def test_force_reload_is_uncached
-    firm = Firm.create!("name" => "A New Firm, Inc")
-    Client.create!("name" => "TheClient.com", :firm => firm)
-
-    ActiveSupport::Deprecation.silence do
-      ActiveRecord::Base.cache do
-        firm.clients.each {}
-        assert_queries(0) { assert_not_nil firm.clients.each {} }
-        assert_queries(1) { assert_not_nil firm.clients(true).each {} }
-      end
-    end
-  end
-
   def test_association_with_references
     firm = companies(:first_firm)
-    assert_includes firm.association_with_references.references_values, 'foo'
+    assert_includes firm.association_with_references.references_values, "foo"
   end
-
 end
 
 class AssociationProxyTest < ActiveRecord::TestCase
-  fixtures :authors, :posts, :categorizations, :categories, :developers, :projects, :developers_projects
+  fixtures :authors, :author_addresses, :posts, :categorizations, :categories, :developers, :projects, :developers_projects
 
   def test_push_does_not_load_target
     david = authors(:david)
 
-    david.posts << (post = Post.new(:title => "New on Edge", :body => "More cool stuff!"))
+    david.posts << (post = Post.new(title: "New on Edge", body: "More cool stuff!"))
     assert !david.posts.loaded?
-    assert david.posts.include?(post)
+    assert_includes david.posts, post
   end
 
   def test_push_has_many_through_does_not_load_target
@@ -143,35 +128,35 @@ class AssociationProxyTest < ActiveRecord::TestCase
 
     david.categories << categories(:technology)
     assert !david.categories.loaded?
-    assert david.categories.include?(categories(:technology))
+    assert_includes david.categories, categories(:technology)
   end
 
   def test_push_followed_by_save_does_not_load_target
     david = authors(:david)
 
-    david.posts << (post = Post.new(:title => "New on Edge", :body => "More cool stuff!"))
+    david.posts << (post = Post.new(title: "New on Edge", body: "More cool stuff!"))
     assert !david.posts.loaded?
     david.save
     assert !david.posts.loaded?
-    assert david.posts.include?(post)
+    assert_includes david.posts, post
   end
 
   def test_push_does_not_lose_additions_to_new_record
-    josh = Author.new(:name => "Josh")
-    josh.posts << Post.new(:title => "New on Edge", :body => "More cool stuff!")
+    josh = Author.new(name: "Josh")
+    josh.posts << Post.new(title: "New on Edge", body: "More cool stuff!")
     assert josh.posts.loaded?
     assert_equal 1, josh.posts.size
   end
 
   def test_append_behaves_like_push
-    josh = Author.new(:name => "Josh")
-    josh.posts.append Post.new(:title => "New on Edge", :body => "More cool stuff!")
+    josh = Author.new(name: "Josh")
+    josh.posts.append Post.new(title: "New on Edge", body: "More cool stuff!")
     assert josh.posts.loaded?
     assert_equal 1, josh.posts.size
   end
 
   def test_prepend_is_not_defined
-    josh = Author.new(:name => "Josh")
+    josh = Author.new(name: "Josh")
     assert_raises(NoMethodError) { josh.posts.prepend Post.new }
   end
 
@@ -183,25 +168,33 @@ class AssociationProxyTest < ActiveRecord::TestCase
     assert !david.projects.loaded?
   end
 
+  def test_load_does_load_target
+    david = developers(:david)
+
+    assert !david.projects.loaded?
+    david.projects.load
+    assert david.projects.loaded?
+  end
+
   def test_inspect_does_not_reload_a_not_yet_loaded_target
-    andreas = Developer.new :name => 'Andreas', :log => 'new developer added'
+    andreas = Developer.new name: "Andreas", log: "new developer added"
     assert !andreas.audit_logs.loaded?
     assert_match(/message: "new developer added"/, andreas.audit_logs.inspect)
   end
 
   def test_save_on_parent_saves_children
-    developer = Developer.create :name => "Bryan", :salary => 50_000
+    developer = Developer.create name: "Bryan", salary: 50_000
     assert_equal 1, developer.reload.audit_logs.size
   end
 
   def test_create_via_association_with_block
-    post = authors(:david).posts.create(:title => "New on Edge") {|p| p.body = "More cool stuff!"}
+    post = authors(:david).posts.create(title: "New on Edge") { |p| p.body = "More cool stuff!" }
     assert_equal post.title, "New on Edge"
     assert_equal post.body, "More cool stuff!"
   end
 
   def test_create_with_bang_via_association_with_block
-    post = authors(:david).posts.create!(:title => "New on Edge") {|p| p.body = "More cool stuff!"}
+    post = authors(:david).posts.create!(title: "New on Edge") { |p| p.body = "More cool stuff!" }
     assert_equal post.title, "New on Edge"
     assert_equal post.body, "More cool stuff!"
   end
@@ -219,7 +212,7 @@ class AssociationProxyTest < ActiveRecord::TestCase
   end
 
   def test_scoped_allows_conditions
-    assert developers(:david).projects.merge(where: 'foo').to_sql.include?('foo')
+    assert developers(:david).projects.merge(where: "foo").to_sql.include?("foo")
   end
 
   test "getting a scope from an association" do
@@ -231,7 +224,14 @@ class AssociationProxyTest < ActiveRecord::TestCase
 
   test "proxy object is cached" do
     david = developers(:david)
-    assert david.projects.equal?(david.projects)
+    assert_same david.projects, david.projects
+  end
+
+  test "proxy object can be stubbed" do
+    david = developers(:david)
+    david.projects.define_singleton_method(:extra_method) { 42 }
+
+    assert_equal 42, david.projects.extra_method
   end
 
   test "inverses get set of subsets of the association" do
@@ -247,7 +247,16 @@ class AssociationProxyTest < ActiveRecord::TestCase
 
   test "first! works on loaded associations" do
     david = authors(:david)
-    assert_equal david.posts.first, david.posts.reload.first!
+    assert_equal david.first_posts.first, david.first_posts.reload.first!
+    assert david.first_posts.loaded?
+    assert_no_queries { david.first_posts.first! }
+  end
+
+  def test_pluck_uses_loaded_target
+    david = authors(:david)
+    assert_equal david.first_posts.pluck(:title), david.first_posts.load.pluck(:title)
+    assert david.first_posts.loaded?
+    assert_no_queries { david.first_posts.pluck(:title) }
   end
 
   def test_reset_unloads_target
@@ -264,18 +273,18 @@ class OverridingAssociationsTest < ActiveRecord::TestCase
   class DifferentPerson < ActiveRecord::Base; end
 
   class PeopleList < ActiveRecord::Base
-    has_and_belongs_to_many :has_and_belongs_to_many, :before_add => :enlist
-    has_many :has_many, :before_add => :enlist
+    has_and_belongs_to_many :has_and_belongs_to_many, before_add: :enlist
+    has_many :has_many, before_add: :enlist
     belongs_to :belongs_to
     has_one :has_one
   end
 
   class DifferentPeopleList < PeopleList
     # Different association with the same name, callbacks should be omitted here.
-    has_and_belongs_to_many :has_and_belongs_to_many, :class_name => 'DifferentPerson'
-    has_many :has_many, :class_name => 'DifferentPerson'
-    belongs_to :belongs_to, :class_name => 'DifferentPerson'
-    has_one :has_one, :class_name => 'DifferentPerson'
+    has_and_belongs_to_many :has_and_belongs_to_many, class_name: "DifferentPerson"
+    has_many :has_many, class_name: "DifferentPerson"
+    belongs_to :belongs_to, class_name: "DifferentPerson"
+    has_one :has_one, class_name: "DifferentPerson"
   end
 
   def test_habtm_association_redefinition_callbacks_should_differ_and_not_inherited
diff --git a/activerecord/test/cases/attribute_decorators_test.rb b/activerecord/test/cases/attribute_decorators_test.rb
index 2aeb2601c2..42eca233ce 100644
--- a/activerecord/test/cases/attribute_decorators_test.rb
+++ b/activerecord/test/cases/attribute_decorators_test.rb
@@ -1,9 +1,11 @@
-require 'cases/helper'
+# frozen_string_literal: true
+
+require "cases/helper"
 
 module ActiveRecord
   class AttributeDecoratorsTest < ActiveRecord::TestCase
     class Model < ActiveRecord::Base
-      self.table_name = 'attribute_decorators_model'
+      self.table_name = "attribute_decorators_model"
     end
 
     class StringDecorator < SimpleDelegator
@@ -28,19 +30,19 @@ module ActiveRecord
 
     teardown do
       return unless @connection
-      @connection.drop_table 'attribute_decorators_model', if_exists: true
+      @connection.drop_table "attribute_decorators_model", if_exists: true
       Model.attribute_type_decorations.clear
       Model.reset_column_information
     end
 
     test "attributes can be decorated" do
-      model = Model.new(a_string: 'Hello')
-      assert_equal 'Hello', model.a_string
+      model = Model.new(a_string: "Hello")
+      assert_equal "Hello", model.a_string
 
       Model.decorate_attribute_type(:a_string, :test) { |t| StringDecorator.new(t) }
 
-      model = Model.new(a_string: 'Hello')
-      assert_equal 'Hello decorated!', model.a_string
+      model = Model.new(a_string: "Hello")
+      assert_equal "Hello decorated!", model.a_string
     end
 
     test "decoration does not eagerly load existing columns" do
@@ -51,54 +53,54 @@ module ActiveRecord
     end
 
     test "undecorated columns are not touched" do
-      Model.attribute :another_string, :string, default: 'something or other'
+      Model.attribute :another_string, :string, default: "something or other"
       Model.decorate_attribute_type(:a_string, :test) { |t| StringDecorator.new(t) }
 
-      assert_equal 'something or other', Model.new.another_string
+      assert_equal "something or other", Model.new.another_string
     end
 
     test "decorators can be chained" do
       Model.decorate_attribute_type(:a_string, :test) { |t| StringDecorator.new(t) }
       Model.decorate_attribute_type(:a_string, :other) { |t| StringDecorator.new(t) }
 
-      model = Model.new(a_string: 'Hello!')
+      model = Model.new(a_string: "Hello!")
 
-      assert_equal 'Hello! decorated! decorated!', model.a_string
+      assert_equal "Hello! decorated! decorated!", model.a_string
     end
 
     test "decoration of the same type multiple times is idempotent" do
       Model.decorate_attribute_type(:a_string, :test) { |t| StringDecorator.new(t) }
       Model.decorate_attribute_type(:a_string, :test) { |t| StringDecorator.new(t) }
 
-      model = Model.new(a_string: 'Hello')
-      assert_equal 'Hello decorated!', model.a_string
+      model = Model.new(a_string: "Hello")
+      assert_equal "Hello decorated!", model.a_string
     end
 
     test "decorations occur in order of declaration" do
       Model.decorate_attribute_type(:a_string, :test) { |t| StringDecorator.new(t) }
       Model.decorate_attribute_type(:a_string, :other) do |type|
-        StringDecorator.new(type, 'decorated again!')
+        StringDecorator.new(type, "decorated again!")
       end
 
-      model = Model.new(a_string: 'Hello!')
+      model = Model.new(a_string: "Hello!")
 
-      assert_equal 'Hello! decorated! decorated again!', model.a_string
+      assert_equal "Hello! decorated! decorated again!", model.a_string
     end
 
     test "decorating attributes does not modify parent classes" do
-      Model.attribute :another_string, :string, default: 'whatever'
+      Model.attribute :another_string, :string, default: "whatever"
       Model.decorate_attribute_type(:a_string, :test) { |t| StringDecorator.new(t) }
       child_class = Class.new(Model)
       child_class.decorate_attribute_type(:another_string, :test) { |t| StringDecorator.new(t) }
       child_class.decorate_attribute_type(:a_string, :other) { |t| StringDecorator.new(t) }
 
-      model = Model.new(a_string: 'Hello!')
-      child = child_class.new(a_string: 'Hello!')
+      model = Model.new(a_string: "Hello!")
+      child = child_class.new(a_string: "Hello!")
 
-      assert_equal 'Hello! decorated!', model.a_string
-      assert_equal 'whatever', model.another_string
-      assert_equal 'Hello! decorated! decorated!', child.a_string
-      assert_equal 'whatever decorated!', child.another_string
+      assert_equal "Hello! decorated!", model.a_string
+      assert_equal "whatever", model.another_string
+      assert_equal "Hello! decorated! decorated!", child.a_string
+      assert_equal "whatever decorated!", child.another_string
     end
 
     class Multiplier < SimpleDelegator
@@ -116,9 +118,9 @@ module ActiveRecord
         Multiplier.new(type)
       end
 
-      model = Model.new(a_string: 'whatever', an_int: 1)
+      model = Model.new(a_string: "whatever", an_int: 1)
 
-      assert_equal 'whatever', model.a_string
+      assert_equal "whatever", model.a_string
       assert_equal 2, model.an_int
     end
   end
diff --git a/activerecord/test/cases/attribute_methods/read_test.rb b/activerecord/test/cases/attribute_methods/read_test.rb
index 74e556211b..0170a6e98d 100644
--- a/activerecord/test/cases/attribute_methods/read_test.rb
+++ b/activerecord/test/cases/attribute_methods/read_test.rb
@@ -1,20 +1,21 @@
+# frozen_string_literal: true
+
 require "cases/helper"
-require 'thread'
 
 module ActiveRecord
   module AttributeMethods
     class ReadTest < ActiveRecord::TestCase
-      class FakeColumn < Struct.new(:name)
+      FakeColumn = Struct.new(:name) do
         def type; :integer; end
       end
 
       def setup
-        @klass = Class.new do
+        @klass = Class.new(Class.new { def self.initialize_generated_modules; end }) do
           def self.superclass; Base; end
           def self.base_class; self; end
           def self.decorate_matching_attribute_types(*); end
-          def self.initialize_generated_modules; end
 
+          include ActiveRecord::DefineCallbacks
           include ActiveRecord::AttributeMethods
 
           def self.attribute_names
@@ -40,13 +41,13 @@ module ActiveRecord
         instance = @klass.new
 
         @klass.attribute_names.each do |name|
-          assert !instance.methods.map(&:to_s).include?(name)
+          assert_not_includes instance.methods.map(&:to_s), name
         end
 
         @klass.define_attribute_methods
 
         @klass.attribute_names.each do |name|
-          assert instance.methods.map(&:to_s).include?(name), "#{name} is not defined"
+          assert_includes instance.methods.map(&:to_s), name, "#{name} is not defined"
         end
       end
 
diff --git a/activerecord/test/cases/attribute_methods_test.rb b/activerecord/test/cases/attribute_methods_test.rb
index 1db52af59b..c48f7d3518 100644
--- a/activerecord/test/cases/attribute_methods_test.rb
+++ b/activerecord/test/cases/attribute_methods_test.rb
@@ -1,15 +1,17 @@
+# frozen_string_literal: true
+
 require "cases/helper"
-require 'models/minimalistic'
-require 'models/developer'
-require 'models/auto_id'
-require 'models/boolean'
-require 'models/computer'
-require 'models/topic'
-require 'models/company'
-require 'models/category'
-require 'models/reply'
-require 'models/contact'
-require 'models/keyboard'
+require "models/minimalistic"
+require "models/developer"
+require "models/auto_id"
+require "models/boolean"
+require "models/computer"
+require "models/topic"
+require "models/company"
+require "models/category"
+require "models/reply"
+require "models/contact"
+require "models/keyboard"
 
 class AttributeMethodsTest < ActiveRecord::TestCase
   include InTimeZone
@@ -19,7 +21,7 @@ class AttributeMethodsTest < ActiveRecord::TestCase
   def setup
     @old_matchers = ActiveRecord::Base.send(:attribute_method_matchers).dup
     @target = Class.new(ActiveRecord::Base)
-    @target.table_name = 'topics'
+    @target.table_name = "topics"
   end
 
   teardown do
@@ -27,15 +29,34 @@ class AttributeMethodsTest < ActiveRecord::TestCase
     ActiveRecord::Base.send(:attribute_method_matchers).concat(@old_matchers)
   end
 
-  def test_attribute_for_inspect
+  test "attribute_for_inspect with a string" do
     t = topics(:first)
     t.title = "The First Topic Now Has A Title With\nNewlines And More Than 50 Characters"
 
-    assert_equal %("#{t.written_on.to_s(:db)}"), t.attribute_for_inspect(:written_on)
     assert_equal '"The First Topic Now Has A Title With\nNewlines And ..."', t.attribute_for_inspect(:title)
   end
 
-  def test_attribute_present
+  test "attribute_for_inspect with a date" do
+    t = topics(:first)
+
+    assert_equal %("#{t.written_on.to_s(:db)}"), t.attribute_for_inspect(:written_on)
+  end
+
+  test "attribute_for_inspect with an array" do
+    t = topics(:first)
+    t.content = [Object.new]
+
+    assert_match %r(\[#<Object:0x[0-9a-f]+>\]), t.attribute_for_inspect(:content)
+  end
+
+  test "attribute_for_inspect with a long array" do
+    t = topics(:first)
+    t.content = (1..11).to_a
+
+    assert_equal "[1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11]", t.attribute_for_inspect(:content)
+  end
+
+  test "attribute_present" do
     t = Topic.new
     t.title = "hello there!"
     t.written_on = Time.now
@@ -46,7 +67,7 @@ class AttributeMethodsTest < ActiveRecord::TestCase
     assert !t.attribute_present?("author_name")
   end
 
-  def test_attribute_present_with_booleans
+  test "attribute_present with booleans" do
     b1 = Boolean.new
     b1.value = false
     assert b1.attribute_present?(:value)
@@ -64,44 +85,44 @@ class AttributeMethodsTest < ActiveRecord::TestCase
     assert Boolean.find(b4.id).attribute_present?(:value)
   end
 
-  def test_caching_nil_primary_key
+  test "caching a nil primary key" do
     klass = Class.new(Minimalistic)
     assert_called(klass, :reset_primary_key, returns: nil) do
       2.times { klass.primary_key }
     end
   end
 
-  def test_attribute_keys_on_new_instance
+  test "attribute keys on a new instance" do
     t = Topic.new
-    assert_equal nil, t.title, "The topics table has a title column, so it should be nil"
+    assert_nil t.title, "The topics table has a title column, so it should be nil"
     assert_raise(NoMethodError) { t.title2 }
   end
 
-  def test_boolean_attributes
+  test "boolean attributes" do
     assert !Topic.find(1).approved?
     assert Topic.find(2).approved?
   end
 
-  def test_set_attributes
+  test "set attributes" do
     topic = Topic.find(1)
-    topic.attributes = { "title" => "Budget", "author_name" => "Jason" }
+    topic.attributes = { title: "Budget", author_name: "Jason" }
     topic.save
     assert_equal("Budget", topic.title)
     assert_equal("Jason", topic.author_name)
     assert_equal(topics(:first).author_email_address, Topic.find(1).author_email_address)
   end
 
-  def test_set_attributes_without_hash
+  test "set attributes without a hash" do
     topic = Topic.new
-    assert_raise(ArgumentError) { topic.attributes = '' }
+    assert_raise(ArgumentError) { topic.attributes = "" }
   end
 
-  def test_integers_as_nil
-    test = AutoId.create('value' => '')
+  test "integers as nil" do
+    test = AutoId.create(value: "")
     assert_nil AutoId.find(test.id).value
   end
 
-  def test_set_attributes_with_block
+  test "set attributes with a block" do
     topic = Topic.new do |t|
       t.title       = "Budget"
       t.author_name = "Jason"
@@ -111,7 +132,7 @@ class AttributeMethodsTest < ActiveRecord::TestCase
     assert_equal("Jason", topic.author_name)
   end
 
-  def test_respond_to?
+  test "respond_to?" do
     topic = Topic.find(1)
     assert_respond_to topic, "title"
     assert_respond_to topic, "title?"
@@ -125,27 +146,27 @@ class AttributeMethodsTest < ActiveRecord::TestCase
     assert !topic.respond_to?(:nothingness)
   end
 
-  def test_respond_to_with_custom_primary_key
+  test "respond_to? with a custom primary key" do
     keyboard = Keyboard.create
     assert_not_nil keyboard.key_number
     assert_equal keyboard.key_number, keyboard.id
-    assert keyboard.respond_to?('key_number')
-    assert keyboard.respond_to?('id')
+    assert keyboard.respond_to?("key_number")
+    assert keyboard.respond_to?("id")
   end
 
-  def test_id_before_type_cast_with_custom_primary_key
+  test "id_before_type_cast with a custom primary key" do
     keyboard = Keyboard.create
-    keyboard.key_number = '10'
-    assert_equal '10', keyboard.id_before_type_cast
-    assert_equal nil, keyboard.read_attribute_before_type_cast('id')
-    assert_equal '10', keyboard.read_attribute_before_type_cast('key_number')
-    assert_equal '10', keyboard.read_attribute_before_type_cast(:key_number)
+    keyboard.key_number = "10"
+    assert_equal "10", keyboard.id_before_type_cast
+    assert_nil keyboard.read_attribute_before_type_cast("id")
+    assert_equal "10", keyboard.read_attribute_before_type_cast("key_number")
+    assert_equal "10", keyboard.read_attribute_before_type_cast(:key_number)
   end
 
-  # Syck calls respond_to? before actually calling initialize
-  def test_respond_to_with_allocated_object
+  # Syck calls respond_to? before actually calling initialize.
+  test "respond_to? with an allocated object" do
     klass = Class.new(ActiveRecord::Base) do
-      self.table_name = 'topics'
+      self.table_name = "topics"
     end
 
     topic = klass.allocate
@@ -155,45 +176,41 @@ class AttributeMethodsTest < ActiveRecord::TestCase
     assert_respond_to topic, :title
   end
 
-  # IRB inspects the return value of "MyModel.allocate".
-  def test_allocated_object_can_be_inspected
+  # IRB inspects the return value of MyModel.allocate.
+  test "allocated objects can be inspected" do
     topic = Topic.allocate
     assert_equal "#<Topic not initialized>", topic.inspect
   end
 
-  def test_array_content
+  test "array content" do
+    content = %w( one two three )
     topic = Topic.new
-    topic.content = %w( one two three )
+    topic.content = content
     topic.save
 
-    assert_equal(%w( one two three ), Topic.find(topic.id).content)
+    assert_equal content, Topic.find(topic.id).content
   end
 
-  def test_read_attributes_before_type_cast
-    category = Category.new({:name=>"Test category", :type => nil})
-    category_attrs = {"name"=>"Test category", "id" => nil, "type" => nil, "categorizations_count" => nil}
-    assert_equal category_attrs , category.attributes_before_type_cast
+  test "read attributes_before_type_cast" do
+    category = Category.new(name: "Test category", type: nil)
+    category_attrs = { "name" => "Test category", "id" => nil, "type" => nil, "categorizations_count" => nil }
+    assert_equal category_attrs, category.attributes_before_type_cast
   end
 
   if current_adapter?(:Mysql2Adapter)
-    def test_read_attributes_before_type_cast_on_boolean
-      bool = Boolean.create!({ "value" => false })
-      if RUBY_PLATFORM =~ /java/
-        # JRuby will return the value before typecast as string
-        assert_equal "0", bool.reload.attributes_before_type_cast["value"]
-      else
-        assert_equal 0, bool.reload.attributes_before_type_cast["value"]
-      end
+    test "read attributes_before_type_cast on a boolean" do
+      bool = Boolean.create!("value" => false)
+      assert_equal 0, bool.reload.attributes_before_type_cast["value"]
     end
   end
 
-  def test_read_attributes_before_type_cast_on_datetime
+  test "read attributes_before_type_cast on a datetime" do
     in_time_zone "Pacific Time (US & Canada)" do
       record = @target.new
 
       record.written_on = "345643456"
       assert_equal "345643456", record.written_on_before_type_cast
-      assert_equal nil, record.written_on
+      assert_nil record.written_on
 
       record.written_on = "2009-10-11 12:13:14"
       assert_equal "2009-10-11 12:13:14", record.written_on_before_type_cast
@@ -202,7 +219,7 @@ class AttributeMethodsTest < ActiveRecord::TestCase
     end
   end
 
-  def test_read_attributes_after_type_cast_on_datetime
+  test "read attributes_after_type_cast on a date" do
     tz = "Pacific Time (US & Canada)"
 
     in_time_zone tz do
@@ -223,7 +240,7 @@ class AttributeMethodsTest < ActiveRecord::TestCase
     end
   end
 
-  def test_hash_content
+  test "hash content" do
     topic = Topic.new
     topic.content = { "one" => 1, "two" => 2 }
     topic.save
@@ -237,7 +254,7 @@ class AttributeMethodsTest < ActiveRecord::TestCase
     assert_equal 3, Topic.find(topic.id).content["three"]
   end
 
-  def test_update_array_content
+  test "update array content" do
     topic = Topic.new
     topic.content = %w( one two three )
 
@@ -251,40 +268,40 @@ class AttributeMethodsTest < ActiveRecord::TestCase
     assert_equal(%w( one two three four five ), topic.content)
   end
 
-  def test_case_sensitive_attributes_hash
-    # DB2 is not case-sensitive
+  test "case-sensitive attributes hash" do
+    # DB2 is not case-sensitive.
     return true if current_adapter?(:DB2Adapter)
 
-    assert_equal @loaded_fixtures['computers']['workstation'].to_hash, Computer.first.attributes
+    assert_equal @loaded_fixtures["computers"]["workstation"].to_hash, Computer.first.attributes
   end
 
-  def test_attributes_without_primary_key
+  test "attributes without primary key" do
     klass = Class.new(ActiveRecord::Base) do
-      self.table_name = 'developers_projects'
+      self.table_name = "developers_projects"
     end
 
     assert_equal klass.column_names, klass.new.attributes.keys
-    assert_not klass.new.has_attribute?('id')
+    assert_not klass.new.has_attribute?("id")
   end
 
-  def test_hashes_not_mangled
-    new_topic = { :title => "New Topic" }
-    new_topic_values = { :title => "AnotherTopic" }
+  test "hashes are not mangled" do
+    new_topic = { title: "New Topic" }
+    new_topic_values = { title: "AnotherTopic" }
 
     topic = Topic.new(new_topic)
     assert_equal new_topic[:title], topic.title
 
-    topic.attributes= new_topic_values
+    topic.attributes = new_topic_values
     assert_equal new_topic_values[:title], topic.title
   end
 
-  def test_create_through_factory
-    topic = Topic.create("title" => "New Topic")
+  test "create through factory" do
+    topic = Topic.create(title: "New Topic")
     topicReloaded = Topic.find(topic.id)
     assert_equal(topic, topicReloaded)
   end
 
-  def test_write_attribute
+  test "write_attribute" do
     topic = Topic.new
     topic.send(:write_attribute, :title, "Still another topic")
     assert_equal "Still another topic", topic.title
@@ -299,7 +316,14 @@ class AttributeMethodsTest < ActiveRecord::TestCase
     assert_equal "Still another topic: part 4", topic.title
   end
 
-  def test_read_attribute
+  test "write_attribute can write aliased attributes as well" do
+    topic = Topic.new(title: "Don't change the topic")
+    topic.write_attribute :heading, "New topic"
+
+    assert_equal "New topic", topic.title
+  end
+
+  test "read_attribute" do
     topic = Topic.new
     topic.title = "Don't change the topic"
     assert_equal "Don't change the topic", topic.read_attribute("title")
@@ -309,15 +333,25 @@ class AttributeMethodsTest < ActiveRecord::TestCase
     assert_equal "Don't change the topic", topic[:title]
   end
 
-  def test_read_attribute_raises_missing_attribute_error_when_not_exists
-    computer = Computer.select('id').first
+  test "read_attribute can read aliased attributes as well" do
+    topic = Topic.new(title: "Don't change the topic")
+
+    assert_equal "Don't change the topic", topic.read_attribute("heading")
+    assert_equal "Don't change the topic", topic["heading"]
+
+    assert_equal "Don't change the topic", topic.read_attribute(:heading)
+    assert_equal "Don't change the topic", topic[:heading]
+  end
+
+  test "read_attribute raises ActiveModel::MissingAttributeError when the attribute does not exist" do
+    computer = Computer.select("id").first
     assert_raises(ActiveModel::MissingAttributeError) { computer[:developer] }
     assert_raises(ActiveModel::MissingAttributeError) { computer[:extendedWarranty] }
-    assert_raises(ActiveModel::MissingAttributeError) { computer[:no_column_exists] = 'Hello!' }
-    assert_nothing_raised { computer[:developer] = 'Hello!' }
+    assert_raises(ActiveModel::MissingAttributeError) { computer[:no_column_exists] = "Hello!" }
+    assert_nothing_raised { computer[:developer] = "Hello!" }
   end
 
-  def test_read_attribute_when_false
+  test "read_attribute when false" do
     topic = topics(:first)
     topic.approved = false
     assert !topic.approved?, "approved should be false"
@@ -325,7 +359,7 @@ class AttributeMethodsTest < ActiveRecord::TestCase
     assert !topic.approved?, "approved should be false"
   end
 
-  def test_read_attribute_when_true
+  test "read_attribute when true" do
     topic = topics(:first)
     topic.approved = true
     assert topic.approved?, "approved should be true"
@@ -333,7 +367,7 @@ class AttributeMethodsTest < ActiveRecord::TestCase
     assert topic.approved?, "approved should be true"
   end
 
-  def test_read_write_boolean_attribute
+  test "boolean attributes writing and reading" do
     topic = Topic.new
     topic.approved = "false"
     assert !topic.approved?, "approved should be false"
@@ -348,7 +382,7 @@ class AttributeMethodsTest < ActiveRecord::TestCase
     assert topic.approved?, "approved should be true"
   end
 
-  def test_overridden_write_attribute
+  test "overridden write_attribute" do
     topic = Topic.new
     def topic.write_attribute(attr_name, value)
       super(attr_name, value.downcase)
@@ -367,7 +401,7 @@ class AttributeMethodsTest < ActiveRecord::TestCase
     assert_equal "yet another topic: part 4", topic.title
   end
 
-  def test_overridden_read_attribute
+  test "overridden read_attribute" do
     topic = Topic.new
     topic.title = "Stop changing the topic"
     def topic.read_attribute(attr_name)
@@ -381,40 +415,40 @@ class AttributeMethodsTest < ActiveRecord::TestCase
     assert_equal "STOP CHANGING THE TOPIC", topic[:title]
   end
 
-  def test_read_overridden_attribute
-    topic = Topic.new(:title => 'a')
-    def topic.title() 'b' end
-    assert_equal 'a', topic[:title]
+  test "read overridden attribute" do
+    topic = Topic.new(title: "a")
+    def topic.title() "b" end
+    assert_equal "a", topic[:title]
   end
 
-  def test_query_attribute_string
+  test "string attribute predicate" do
     [nil, "", " "].each do |value|
-      assert_equal false, Topic.new(:author_name => value).author_name?
+      assert_equal false, Topic.new(author_name: value).author_name?
     end
 
-    assert_equal true, Topic.new(:author_name => "Name").author_name?
+    assert_equal true, Topic.new(author_name: "Name").author_name?
   end
 
-  def test_query_attribute_number
+  test "number attribute predicate" do
     [nil, 0, "0"].each do |value|
-      assert_equal false, Developer.new(:salary => value).salary?
+      assert_equal false, Developer.new(salary: value).salary?
     end
 
-    assert_equal true, Developer.new(:salary => 1).salary?
-    assert_equal true, Developer.new(:salary => "1").salary?
+    assert_equal true, Developer.new(salary: 1).salary?
+    assert_equal true, Developer.new(salary: "1").salary?
   end
 
-  def test_query_attribute_boolean
+  test "boolean attribute predicate" do
     [nil, "", false, "false", "f", 0].each do |value|
-      assert_equal false, Topic.new(:approved => value).approved?
+      assert_equal false, Topic.new(approved: value).approved?
     end
 
     [true, "true", "1", 1].each do |value|
-      assert_equal true, Topic.new(:approved => value).approved?
+      assert_equal true, Topic.new(approved: value).approved?
     end
   end
 
-  def test_query_attribute_with_custom_fields
+  test "custom field attribute predicate" do
     object = Company.find_by_sql(<<-SQL).first
       SELECT c1.*, c2.type as string_value, c2.rating as int_value
         FROM companies c1, companies c2
@@ -435,95 +469,95 @@ class AttributeMethodsTest < ActiveRecord::TestCase
     assert !object.int_value?
   end
 
-  def test_non_attribute_access_and_assignment
+  test "non-attribute read and write" do
     topic = Topic.new
     assert !topic.respond_to?("mumbo")
     assert_raise(NoMethodError) { topic.mumbo }
     assert_raise(NoMethodError) { topic.mumbo = 5 }
   end
 
-  def test_undeclared_attribute_method_does_not_affect_respond_to_and_method_missing
-    topic = @target.new(:title => 'Budget')
-    assert topic.respond_to?('title')
-    assert_equal 'Budget', topic.title
-    assert !topic.respond_to?('title_hello_world')
+  test "undeclared attribute method does not affect respond_to? and method_missing" do
+    topic = @target.new(title: "Budget")
+    assert topic.respond_to?("title")
+    assert_equal "Budget", topic.title
+    assert !topic.respond_to?("title_hello_world")
     assert_raise(NoMethodError) { topic.title_hello_world }
   end
 
-  def test_declared_prefixed_attribute_method_affects_respond_to_and_method_missing
-    topic = @target.new(:title => 'Budget')
+  test "declared prefixed attribute method affects respond_to? and method_missing" do
+    topic = @target.new(title: "Budget")
     %w(default_ title_).each do |prefix|
       @target.class_eval "def #{prefix}attribute(*args) args end"
       @target.attribute_method_prefix prefix
 
       meth = "#{prefix}title"
       assert topic.respond_to?(meth)
-      assert_equal ['title'], topic.send(meth)
-      assert_equal ['title', 'a'], topic.send(meth, 'a')
-      assert_equal ['title', 1, 2, 3], topic.send(meth, 1, 2, 3)
+      assert_equal ["title"], topic.send(meth)
+      assert_equal ["title", "a"], topic.send(meth, "a")
+      assert_equal ["title", 1, 2, 3], topic.send(meth, 1, 2, 3)
     end
   end
 
-  def test_declared_suffixed_attribute_method_affects_respond_to_and_method_missing
+  test "declared suffixed attribute method affects respond_to? and method_missing" do
     %w(_default _title_default _it! _candidate= able?).each do |suffix|
       @target.class_eval "def attribute#{suffix}(*args) args end"
       @target.attribute_method_suffix suffix
-      topic = @target.new(:title => 'Budget')
+      topic = @target.new(title: "Budget")
 
       meth = "title#{suffix}"
       assert topic.respond_to?(meth)
-      assert_equal ['title'], topic.send(meth)
-      assert_equal ['title', 'a'], topic.send(meth, 'a')
-      assert_equal ['title', 1, 2, 3], topic.send(meth, 1, 2, 3)
+      assert_equal ["title"], topic.send(meth)
+      assert_equal ["title", "a"], topic.send(meth, "a")
+      assert_equal ["title", 1, 2, 3], topic.send(meth, 1, 2, 3)
     end
   end
 
-  def test_declared_affixed_attribute_method_affects_respond_to_and_method_missing
-    [['mark_', '_for_update'], ['reset_', '!'], ['default_', '_value?']].each do |prefix, suffix|
+  test "declared affixed attribute method affects respond_to? and method_missing" do
+    [["mark_", "_for_update"], ["reset_", "!"], ["default_", "_value?"]].each do |prefix, suffix|
       @target.class_eval "def #{prefix}attribute#{suffix}(*args) args end"
-      @target.attribute_method_affix({ :prefix => prefix, :suffix => suffix })
-      topic = @target.new(:title => 'Budget')
+      @target.attribute_method_affix(prefix: prefix, suffix: suffix)
+      topic = @target.new(title: "Budget")
 
       meth = "#{prefix}title#{suffix}"
       assert topic.respond_to?(meth)
-      assert_equal ['title'], topic.send(meth)
-      assert_equal ['title', 'a'], topic.send(meth, 'a')
-      assert_equal ['title', 1, 2, 3], topic.send(meth, 1, 2, 3)
+      assert_equal ["title"], topic.send(meth)
+      assert_equal ["title", "a"], topic.send(meth, "a")
+      assert_equal ["title", 1, 2, 3], topic.send(meth, 1, 2, 3)
     end
   end
 
-  def test_should_unserialize_attributes_for_frozen_records
-    myobj = {:value1 => :value2}
-    topic = Topic.create("content" => myobj)
+  test "should unserialize attributes for frozen records" do
+    myobj = { value1: :value2 }
+    topic = Topic.create(content: myobj)
     topic.freeze
     assert_equal myobj, topic.content
   end
 
-  def test_typecast_attribute_from_select_to_false
-    Topic.create(:title => 'Budget')
-    # Oracle does not support boolean expressions in SELECT
+  test "typecast attribute from select to false" do
+    Topic.create(title: "Budget")
+    # Oracle does not support boolean expressions in SELECT.
     if current_adapter?(:OracleAdapter, :FbAdapter)
-      topic = Topic.all.merge!(:select => "topics.*, 0 as is_test").first
+      topic = Topic.all.merge!(select: "topics.*, 0 as is_test").first
     else
-      topic = Topic.all.merge!(:select => "topics.*, 1=2 as is_test").first
+      topic = Topic.all.merge!(select: "topics.*, 1=2 as is_test").first
     end
     assert !topic.is_test?
   end
 
-  def test_typecast_attribute_from_select_to_true
-    Topic.create(:title => 'Budget')
-    # Oracle does not support boolean expressions in SELECT
+  test "typecast attribute from select to true" do
+    Topic.create(title: "Budget")
+    # Oracle does not support boolean expressions in SELECT.
     if current_adapter?(:OracleAdapter, :FbAdapter)
-      topic = Topic.all.merge!(:select => "topics.*, 1 as is_test").first
+      topic = Topic.all.merge!(select: "topics.*, 1 as is_test").first
     else
-      topic = Topic.all.merge!(:select => "topics.*, 2=2 as is_test").first
+      topic = Topic.all.merge!(select: "topics.*, 2=2 as is_test").first
     end
     assert topic.is_test?
   end
 
-  def test_raises_dangerous_attribute_error_when_defining_activerecord_method_in_model
+  test "raises ActiveRecord::DangerousAttributeError when defining an AR method in a model" do
     %w(save create_or_update).each do |method|
-      klass = Class.new ActiveRecord::Base
+      klass = Class.new(ActiveRecord::Base)
       klass.class_eval "def #{method}() 'defined #{method}' end"
       assert_raise ActiveRecord::DangerousAttributeError do
         klass.instance_method_already_implemented?(method)
@@ -531,7 +565,7 @@ class AttributeMethodsTest < ActiveRecord::TestCase
     end
   end
 
-  def test_converted_values_are_returned_after_assignment
+  test "converted values are returned after assignment" do
     developer = Developer.new(name: 1337, salary: "50000")
 
     assert_equal "50000", developer.salary_before_type_cast
@@ -546,7 +580,7 @@ class AttributeMethodsTest < ActiveRecord::TestCase
     assert_equal "1337", developer.name
   end
 
-  def test_write_nil_to_time_attributes
+  test "write nil to time attribute" do
     in_time_zone "Pacific Time (US & Canada)" do
       record = @target.new
       record.written_on = nil
@@ -554,7 +588,7 @@ class AttributeMethodsTest < ActiveRecord::TestCase
     end
   end
 
-  def test_write_time_to_date_attributes
+  test "write time to date attribute" do
     in_time_zone "Pacific Time (US & Canada)" do
       record = @target.new
       record.last_read = Time.utc(2010, 1, 1, 10)
@@ -562,7 +596,7 @@ class AttributeMethodsTest < ActiveRecord::TestCase
     end
   end
 
-  def test_time_attributes_are_retrieved_in_current_time_zone
+  test "time attributes are retrieved in the current time zone" do
     in_time_zone "Pacific Time (US & Canada)" do
       utc_time = Time.utc(2008, 1, 1)
       record   = @target.new
@@ -574,7 +608,7 @@ class AttributeMethodsTest < ActiveRecord::TestCase
     end
   end
 
-  def test_setting_time_zone_aware_attribute_to_utc
+  test "setting a time zone-aware attribute to UTC" do
     in_time_zone "Pacific Time (US & Canada)" do
       utc_time = Time.utc(2008, 1, 1)
       record   = @target.new
@@ -585,11 +619,11 @@ class AttributeMethodsTest < ActiveRecord::TestCase
     end
   end
 
-  def test_setting_time_zone_aware_attribute_in_other_time_zone
+  test "setting time zone-aware attribute in other time zone" do
     utc_time = Time.utc(2008, 1, 1)
     cst_time = utc_time.in_time_zone("Central Time (US & Canada)")
     in_time_zone "Pacific Time (US & Canada)" do
-      record   = @target.new
+      record = @target.new
       record.written_on = cst_time
       assert_equal utc_time, record.written_on
       assert_equal ActiveSupport::TimeZone["Pacific Time (US & Canada)"], record.written_on.time_zone
@@ -597,23 +631,23 @@ class AttributeMethodsTest < ActiveRecord::TestCase
     end
   end
 
-  def test_setting_time_zone_aware_read_attribute
+  test "setting time zone-aware read attribute" do
     utc_time = Time.utc(2008, 1, 1)
     cst_time = utc_time.in_time_zone("Central Time (US & Canada)")
     in_time_zone "Pacific Time (US & Canada)" do
-      record = @target.create(:written_on => cst_time).reload
+      record = @target.create(written_on: cst_time).reload
       assert_equal utc_time, record[:written_on]
       assert_equal ActiveSupport::TimeZone["Pacific Time (US & Canada)"], record[:written_on].time_zone
       assert_equal Time.utc(2007, 12, 31, 16), record[:written_on].time
     end
   end
 
-  def test_setting_time_zone_aware_attribute_with_string
+  test "setting time zone-aware attribute with a string" do
     utc_time = Time.utc(2008, 1, 1)
     (-11..13).each do |timezone_offset|
       time_string = utc_time.in_time_zone(timezone_offset).to_s
       in_time_zone "Pacific Time (US & Canada)" do
-        record   = @target.new
+        record = @target.new
         record.written_on = time_string
         assert_equal Time.zone.parse(time_string), record.written_on
         assert_equal ActiveSupport::TimeZone["Pacific Time (US & Canada)"], record.written_on.time_zone
@@ -622,30 +656,30 @@ class AttributeMethodsTest < ActiveRecord::TestCase
     end
   end
 
-  def test_time_zone_aware_attribute_saved
+  test "time zone-aware attribute saved" do
     in_time_zone 1 do
-      record = @target.create(:written_on => '2012-02-20 10:00')
+      record = @target.create(written_on: "2012-02-20 10:00")
 
-      record.written_on = '2012-02-20 09:00'
+      record.written_on = "2012-02-20 09:00"
       record.save
       assert_equal Time.zone.local(2012, 02, 20, 9), record.reload.written_on
     end
   end
 
-  def test_setting_time_zone_aware_attribute_to_blank_string_returns_nil
+  test "setting a time zone-aware attribute to a blank string returns nil" do
     in_time_zone "Pacific Time (US & Canada)" do
-      record   = @target.new
-      record.written_on = ' '
+      record = @target.new
+      record.written_on = " "
       assert_nil record.written_on
       assert_nil record[:written_on]
     end
   end
 
-  def test_setting_time_zone_aware_attribute_interprets_time_zone_unaware_string_in_time_zone
-    time_string = 'Tue Jan 01 00:00:00 2008'
+  test "setting a time zone-aware attribute interprets time zone-unaware string in time zone" do
+    time_string = "Tue Jan 01 00:00:00 2008"
     (-11..13).each do |timezone_offset|
       in_time_zone timezone_offset do
-        record   = @target.new
+        record = @target.new
         record.written_on = time_string
         assert_equal Time.zone.parse(time_string), record.written_on
         assert_equal ActiveSupport::TimeZone[timezone_offset], record.written_on.time_zone
@@ -654,10 +688,10 @@ class AttributeMethodsTest < ActiveRecord::TestCase
     end
   end
 
-  def test_setting_time_zone_aware_datetime_in_current_time_zone
+  test "setting a time zone-aware datetime in the current time zone" do
     utc_time = Time.utc(2008, 1, 1)
     in_time_zone "Pacific Time (US & Canada)" do
-      record   = @target.new
+      record = @target.new
       record.written_on = utc_time.in_time_zone
       assert_equal utc_time, record.written_on
       assert_equal ActiveSupport::TimeZone["Pacific Time (US & Canada)"], record.written_on.time_zone
@@ -665,7 +699,7 @@ class AttributeMethodsTest < ActiveRecord::TestCase
     end
   end
 
-  def test_yaml_dumping_record_with_time_zone_aware_attribute
+  test "YAML dumping a record with time zone-aware attribute" do
     in_time_zone "Pacific Time (US & Canada)" do
       record = Topic.new(id: 1)
       record.written_on = "Jan 01 00:00:00 2014"
@@ -673,7 +707,7 @@ class AttributeMethodsTest < ActiveRecord::TestCase
     end
   end
 
-  def test_setting_time_zone_aware_time_in_current_time_zone
+  test "setting a time zone-aware time in the current time zone" do
     in_time_zone "Pacific Time (US & Canada)" do
       record = @target.new
       time_string = "10:00:00"
@@ -683,12 +717,12 @@ class AttributeMethodsTest < ActiveRecord::TestCase
       assert_equal expected_time, record.bonus_time
       assert_equal ActiveSupport::TimeZone["Pacific Time (US & Canada)"], record.bonus_time.time_zone
 
-      record.bonus_time = ''
+      record.bonus_time = ""
       assert_nil record.bonus_time
     end
   end
 
-  def test_setting_time_zone_aware_time_with_dst
+  test "setting a time zone-aware time with DST" do
     in_time_zone "Pacific Time (US & Canada)" do
       current_time = Time.zone.local(2014, 06, 15, 10)
       record = @target.new(bonus_time: current_time)
@@ -702,7 +736,7 @@ class AttributeMethodsTest < ActiveRecord::TestCase
     end
   end
 
-  def test_removing_time_zone_aware_types
+  test "removing time zone-aware types" do
     with_time_zone_aware_types(:datetime) do
       in_time_zone "Pacific Time (US & Canada)" do
         record = @target.new(bonus_time: "10:00:00")
@@ -714,14 +748,14 @@ class AttributeMethodsTest < ActiveRecord::TestCase
     end
   end
 
-  def test_time_zone_aware_attributes_dont_recurse_infinitely_on_invalid_values
+  test "time zone-aware attributes do not recurse infinitely on invalid values" do
     in_time_zone "Pacific Time (US & Canada)" do
       record = @target.new(bonus_time: [])
-      assert_equal nil, record.bonus_time
+      assert_nil record.bonus_time
     end
   end
 
-  def test_setting_time_zone_conversion_for_attributes_should_write_value_on_class_variable
+  test "setting a time_zone_conversion_for_attributes should write the value on a class variable" do
     Topic.skip_time_zone_conversion_for_attributes = [:field_a]
     Minimalistic.skip_time_zone_conversion_for_attributes = [:field_b]
 
@@ -729,44 +763,44 @@ class AttributeMethodsTest < ActiveRecord::TestCase
     assert_equal [:field_b], Minimalistic.skip_time_zone_conversion_for_attributes
   end
 
-  def test_read_attributes_respect_access_control
+  test "attribute readers respect access control" do
     privatize("title")
 
-    topic = @target.new(:title => "The pros and cons of programming naked.")
+    topic = @target.new(title: "The pros and cons of programming naked.")
     assert !topic.respond_to?(:title)
     exception = assert_raise(NoMethodError) { topic.title }
-    assert exception.message.include?("private method")
+    assert_includes exception.message, "private method"
     assert_equal "I'm private", topic.send(:title)
   end
 
-  def test_write_attributes_respect_access_control
+  test "attribute writers respect access control" do
     privatize("title=(value)")
 
     topic = @target.new
     assert !topic.respond_to?(:title=)
-    exception = assert_raise(NoMethodError) { topic.title = "Pants"}
-    assert exception.message.include?("private method")
+    exception = assert_raise(NoMethodError) { topic.title = "Pants" }
+    assert_includes exception.message, "private method"
     topic.send(:title=, "Very large pants")
   end
 
-  def test_question_attributes_respect_access_control
+  test "attribute predicates respect access control" do
     privatize("title?")
 
-    topic = @target.new(:title => "Isaac Newton's pants")
+    topic = @target.new(title: "Isaac Newton's pants")
     assert !topic.respond_to?(:title?)
     exception = assert_raise(NoMethodError) { topic.title? }
-    assert exception.message.include?("private method")
+    assert_includes exception.message, "private method"
     assert topic.send(:title?)
   end
 
-  def test_bulk_update_respects_access_control
+  test "bulk updates respect access control" do
     privatize("title=(value)")
 
-    assert_raise(ActiveRecord::UnknownAttributeError) { @target.new(:title => "Rants about pants") }
-    assert_raise(ActiveRecord::UnknownAttributeError) { @target.new.attributes = { :title => "Ants in pants" } }
+    assert_raise(ActiveRecord::UnknownAttributeError) { @target.new(title: "Rants about pants") }
+    assert_raise(ActiveRecord::UnknownAttributeError) { @target.new.attributes = { title: "Ants in pants" } }
   end
 
-  def test_bulk_update_raise_unknown_attribute_error
+  test "bulk update raises ActiveRecord::UnknownAttributeError" do
     error = assert_raises(ActiveRecord::UnknownAttributeError) {
       Topic.new(hello: "world")
     }
@@ -775,22 +809,22 @@ class AttributeMethodsTest < ActiveRecord::TestCase
     assert_equal "unknown attribute 'hello' for Topic.", error.message
   end
 
-  def test_methods_override_in_multi_level_subclass
+  test "method overrides in multi-level subclasses" do
     klass = Class.new(Developer) do
       def name
         "dev:#{read_attribute(:name)}"
       end
     end
 
-    2.times { klass = Class.new klass }
-    dev = klass.new(name: 'arthurnn')
+    2.times { klass = Class.new(klass) }
+    dev = klass.new(name: "arthurnn")
     dev.save!
-    assert_equal 'dev:arthurnn', dev.reload.name
+    assert_equal "dev:arthurnn", dev.reload.name
   end
 
-  def test_global_methods_are_overwritten
+  test "global methods are overwritten" do
     klass = Class.new(ActiveRecord::Base) do
-      self.table_name = 'computers'
+      self.table_name = "computers"
     end
 
     assert !klass.instance_method_already_implemented?(:system)
@@ -798,11 +832,13 @@ class AttributeMethodsTest < ActiveRecord::TestCase
     assert_nil computer.system
   end
 
-  def test_global_methods_are_overwritten_when_subclassing
-    klass = Class.new(ActiveRecord::Base) { self.abstract_class = true }
+  test "global methods are overwritten when subclassing" do
+    klass = Class.new(ActiveRecord::Base) do
+      self.abstract_class = true
+    end
 
     subklass = Class.new(klass) do
-      self.table_name = 'computers'
+      self.table_name = "computers"
     end
 
     assert !klass.instance_method_already_implemented?(:system)
@@ -811,7 +847,7 @@ class AttributeMethodsTest < ActiveRecord::TestCase
     assert_nil computer.system
   end
 
-  def test_instance_method_should_be_defined_on_the_base_class
+  test "instance methods should be defined on the base class" do
     subklass = Class.new(Topic)
 
     Topic.define_attribute_methods
@@ -827,14 +863,21 @@ class AttributeMethodsTest < ActiveRecord::TestCase
     assert subklass.method_defined?(:id), "subklass is missing id method"
   end
 
-  def test_read_attribute_with_nil_should_not_asplode
-    assert_equal nil, Topic.new.read_attribute(nil)
+  test "define_attribute_method works with both symbol and string" do
+    klass = Class.new(ActiveRecord::Base)
+
+    assert_nothing_raised { klass.define_attribute_method(:foo) }
+    assert_nothing_raised { klass.define_attribute_method("bar") }
+  end
+
+  test "read_attribute with nil should not asplode" do
+    assert_nil Topic.new.read_attribute(nil)
   end
 
   # If B < A, and A defines an accessor for 'foo', we don't want to override
   # that by defining a 'foo' method in the generated methods module for B.
   # (That module will be inserted between the two, e.g. [B, <GeneratedAttributes>, A].)
-  def test_inherited_custom_accessors
+  test "inherited custom accessors" do
     klass = new_topic_like_ar_class do
       self.abstract_class = true
       def title; "omg"; end
@@ -850,9 +893,9 @@ class AttributeMethodsTest < ActiveRecord::TestCase
     assert_equal "lol", topic.author_name
   end
 
-  def test_inherited_custom_accessors_with_reserved_names
+  test "inherited custom accessors with reserved names" do
     klass = Class.new(ActiveRecord::Base) do
-      self.table_name = 'computers'
+      self.table_name = "computers"
       self.abstract_class = true
       def system; "omg"; end
       def system=(val); self.developer = val; end
@@ -868,18 +911,18 @@ class AttributeMethodsTest < ActiveRecord::TestCase
     assert_equal 99, computer.developer
   end
 
-  def test_on_the_fly_super_invokable_generated_attribute_methods_via_method_missing
+  test "on_the_fly_super_invokable_generated_attribute_methods_via_method_missing" do
     klass = new_topic_like_ar_class do
       def title
-        super + '!'
+        super + "!"
       end
     end
 
     real_topic = topics(:first)
-    assert_equal real_topic.title + '!', klass.find(real_topic.id).title
+    assert_equal real_topic.title + "!", klass.find(real_topic.id).title
   end
 
-  def test_on_the_fly_super_invokable_generated_predicate_attribute_methods_via_method_missing
+  test "on-the-fly super-invokable generated attribute predicates via method_missing" do
     klass = new_topic_like_ar_class do
       def title?
         !super
@@ -890,7 +933,7 @@ class AttributeMethodsTest < ActiveRecord::TestCase
     assert_equal !real_topic.title?, klass.find(real_topic.id).title?
   end
 
-  def test_calling_super_when_parent_does_not_define_method_raises_error
+  test "calling super when the parent does not define method raises NoMethodError" do
     klass = new_topic_like_ar_class do
       def some_method_that_is_not_on_super
         super
@@ -902,38 +945,38 @@ class AttributeMethodsTest < ActiveRecord::TestCase
     end
   end
 
-  def test_attribute_method?
+  test "attribute_method?" do
     assert @target.attribute_method?(:title)
     assert @target.attribute_method?(:title=)
     assert_not @target.attribute_method?(:wibble)
   end
 
-  def test_attribute_method_returns_false_if_table_does_not_exist
-    @target.table_name = 'wibble'
+  test "attribute_method? returns false if the table does not exist" do
+    @target.table_name = "wibble"
     assert_not @target.attribute_method?(:title)
   end
 
-  def test_attribute_names_on_new_record
+  test "attribute_names on a new record" do
     model = @target.new
 
     assert_equal @target.column_names, model.attribute_names
   end
 
-  def test_attribute_names_on_queried_record
+  test "attribute_names on a queried record" do
     model = @target.last!
 
     assert_equal @target.column_names, model.attribute_names
   end
 
-  def test_attribute_names_with_custom_select
-    model = @target.select('id').last!
+  test "attribute_names with a custom select" do
+    model = @target.select("id").last!
 
-    assert_equal ['id'], model.attribute_names
-    # Sanity check, make sure other columns exist
-    assert_not_equal ['id'], @target.column_names
+    assert_equal ["id"], model.attribute_names
+    # Sanity check, make sure other columns exist.
+    assert_not_equal ["id"], @target.column_names
   end
 
-  def test_came_from_user
+  test "came_from_user?" do
     model = @target.first
 
     assert_not model.id_came_from_user?
@@ -941,7 +984,7 @@ class AttributeMethodsTest < ActiveRecord::TestCase
     assert model.id_came_from_user?
   end
 
-  def test_accessed_fields
+  test "accessed_fields" do
     model = @target.first
 
     assert_equal [], model.accessed_fields
@@ -951,40 +994,37 @@ class AttributeMethodsTest < ActiveRecord::TestCase
     assert_equal ["title"], model.accessed_fields
   end
 
-  private
-
-  def new_topic_like_ar_class(&block)
-    klass = Class.new(ActiveRecord::Base) do
-      self.table_name = 'topics'
-      class_eval(&block)
-    end
-
-    assert_empty klass.generated_attribute_methods.instance_methods(false)
-    klass
+  test "generated attribute methods ancestors have correct class" do
+    mod = Topic.send(:generated_attribute_methods)
+    assert_match %r(GeneratedAttributeMethods), mod.inspect
   end
 
-  def with_time_zone_aware_types(*types)
-    old_types = ActiveRecord::Base.time_zone_aware_types
-    ActiveRecord::Base.time_zone_aware_types = types
-    yield
-  ensure
-    ActiveRecord::Base.time_zone_aware_types = old_types
-  end
+  private
 
-  def cached_columns
-    Topic.columns.map(&:name)
-  end
+    def new_topic_like_ar_class(&block)
+      klass = Class.new(ActiveRecord::Base) do
+        self.table_name = "topics"
+        class_eval(&block)
+      end
 
-  def time_related_columns_on_topic
-    Topic.columns.select { |c| [:time, :date, :datetime, :timestamp].include?(c.type) }
-  end
+      assert_empty klass.send(:generated_attribute_methods).instance_methods(false)
+      klass
+    end
 
-  def privatize(method_signature)
-    @target.class_eval(<<-private_method, __FILE__, __LINE__ + 1)
-      private
-      def #{method_signature}
-        "I'm private"
-      end
-    private_method
-  end
+    def with_time_zone_aware_types(*types)
+      old_types = ActiveRecord::Base.time_zone_aware_types
+      ActiveRecord::Base.time_zone_aware_types = types
+      yield
+    ensure
+      ActiveRecord::Base.time_zone_aware_types = old_types
+    end
+
+    def privatize(method_signature)
+      @target.class_eval(<<-private_method, __FILE__, __LINE__ + 1)
+        private
+        def #{method_signature}
+          "I'm private"
+        end
+      private_method
+    end
 end
diff --git a/activerecord/test/cases/attributes_test.rb b/activerecord/test/cases/attributes_test.rb
index 7bcaa53aa2..8ebfee61ff 100644
--- a/activerecord/test/cases/attributes_test.rb
+++ b/activerecord/test/cases/attributes_test.rb
@@ -1,10 +1,12 @@
-require 'cases/helper'
+# frozen_string_literal: true
+
+require "cases/helper"
 
 class OverloadedType < ActiveRecord::Base
   attribute :overloaded_float, :integer
   attribute :overloaded_string_with_limit, :string, limit: 50
   attribute :non_existent_decimal, :decimal
-  attribute :string_with_default, :string, default: 'the overloaded default'
+  attribute :string_with_default, :string, default: "the overloaded default"
 end
 
 class ChildOfOverloadedType < OverloadedType
@@ -15,7 +17,7 @@ class GrandchildOfOverloadedType < ChildOfOverloadedType
 end
 
 class UnoverloadedType < ActiveRecord::Base
-  self.table_name = 'overloaded_types'
+  self.table_name = "overloaded_types"
 end
 
 module ActiveRecord
@@ -44,20 +46,20 @@ module ActiveRecord
     end
 
     test "properties assigned in constructor" do
-      data = OverloadedType.new(overloaded_float: '3.3')
+      data = OverloadedType.new(overloaded_float: "3.3")
 
       assert_equal 3, data.overloaded_float
     end
 
     test "overloaded properties with limit" do
-      assert_equal 50, OverloadedType.type_for_attribute('overloaded_string_with_limit').limit
-      assert_equal 255, UnoverloadedType.type_for_attribute('overloaded_string_with_limit').limit
+      assert_equal 50, OverloadedType.type_for_attribute("overloaded_string_with_limit").limit
+      assert_equal 255, UnoverloadedType.type_for_attribute("overloaded_string_with_limit").limit
     end
 
     test "nonexistent attribute" do
       data = OverloadedType.new(non_existent_decimal: 1)
 
-      assert_equal BigDecimal.new(1), data.non_existent_decimal
+      assert_equal BigDecimal(1), data.non_existent_decimal
       assert_raise ActiveRecord::UnknownAttributeError do
         UnoverloadedType.new(non_existent_decimal: 1)
       end
@@ -65,7 +67,7 @@ module ActiveRecord
 
     test "model with nonexistent attribute with default value can be saved" do
       klass = Class.new(OverloadedType) do
-        attribute :non_existent_string_with_default, :string, default: 'nonexistent'
+        attribute :non_existent_string_with_default, :string, default: "nonexistent"
       end
 
       model = klass.new
@@ -76,22 +78,22 @@ module ActiveRecord
       data = OverloadedType.new
       unoverloaded_data = UnoverloadedType.new
 
-      assert_equal 'the overloaded default', data.string_with_default
-      assert_equal 'the original default', unoverloaded_data.string_with_default
+      assert_equal "the overloaded default", data.string_with_default
+      assert_equal "the original default", unoverloaded_data.string_with_default
     end
 
     test "defaults are not touched on the columns" do
-      assert_equal 'the original default', OverloadedType.columns_hash['string_with_default'].default
+      assert_equal "the original default", OverloadedType.columns_hash["string_with_default"].default
     end
 
     test "children inherit custom properties" do
-      data = ChildOfOverloadedType.new(overloaded_float: '4.4')
+      data = ChildOfOverloadedType.new(overloaded_float: "4.4")
 
       assert_equal 4, data.overloaded_float
     end
 
     test "children can override parents" do
-      data = GrandchildOfOverloadedType.new(overloaded_float: '4.4')
+      data = GrandchildOfOverloadedType.new(overloaded_float: "4.4")
 
       assert_equal 4.4, data.overloaded_float
     end
@@ -106,13 +108,15 @@ module ActiveRecord
 
       assert_equal 6, klass.attribute_types.length
       assert_equal 6, klass.column_defaults.length
-      assert_not klass.attribute_types.include?('wibble')
+      assert_equal 6, klass.attribute_names.length
+      assert_not klass.attribute_types.include?("wibble")
 
       klass.attribute :wibble, Type::Value.new
 
       assert_equal 7, klass.attribute_types.length
       assert_equal 7, klass.column_defaults.length
-      assert klass.attribute_types.include?('wibble')
+      assert_equal 7, klass.attribute_names.length
+      assert_includes klass.attribute_types, "wibble"
     end
 
     test "the given default value is cast from user" do
@@ -205,5 +209,63 @@ module ActiveRecord
 
       assert_equal(:bar, child.new(foo: :bar).foo)
     end
+
+    test "attributes not backed by database columns are not dirty when unchanged" do
+      refute OverloadedType.new.non_existent_decimal_changed?
+    end
+
+    test "attributes not backed by database columns are always initialized" do
+      OverloadedType.create!
+      model = OverloadedType.first
+
+      assert_nil model.non_existent_decimal
+      model.non_existent_decimal = "123"
+      assert_equal 123, model.non_existent_decimal
+    end
+
+    test "attributes not backed by database columns return the default on models loaded from database" do
+      child = Class.new(OverloadedType) do
+        attribute :non_existent_decimal, :decimal, default: 123
+      end
+      child.create!
+      model = child.first
+
+      assert_equal 123, model.non_existent_decimal
+    end
+
+    test "attributes not backed by database columns properly interact with mutation and dirty" do
+      child = Class.new(ActiveRecord::Base) do
+        self.table_name = "topics"
+        attribute :foo, :string, default: "lol"
+      end
+      child.create!
+      model = child.first
+
+      assert_equal "lol", model.foo
+
+      model.foo << "asdf"
+      assert_equal "lolasdf", model.foo
+      assert model.foo_changed?
+
+      model.reload
+      assert_equal "lol", model.foo
+
+      model.foo = "lol"
+      refute model.changed?
+    end
+
+    test "attributes not backed by database columns appear in inspect" do
+      inspection = OverloadedType.new.inspect
+
+      assert_includes inspection, "non_existent_decimal"
+    end
+
+    test "attributes do not require a type" do
+      klass = Class.new(OverloadedType) do
+        attribute :no_type
+      end
+      assert_equal 1, klass.new(no_type: 1).no_type
+      assert_equal "foo", klass.new(no_type: "foo").no_type
+    end
   end
 end
diff --git a/activerecord/test/cases/autosave_association_test.rb b/activerecord/test/cases/autosave_association_test.rb
index 9e3266b7d6..4d8368fd8a 100644
--- a/activerecord/test/cases/autosave_association_test.rb
+++ b/activerecord/test/cases/autosave_association_test.rb
@@ -1,55 +1,56 @@
-require 'cases/helper'
-require 'models/bird'
-require 'models/comment'
-require 'models/company'
-require 'models/customer'
-require 'models/developer'
-require 'models/computer'
-require 'models/invoice'
-require 'models/line_item'
-require 'models/order'
-require 'models/parrot'
-require 'models/person'
-require 'models/pirate'
-require 'models/post'
-require 'models/reader'
-require 'models/ship'
-require 'models/ship_part'
-require 'models/tag'
-require 'models/tagging'
-require 'models/treasure'
-require 'models/eye'
-require 'models/electron'
-require 'models/molecule'
-require 'models/member'
-require 'models/member_detail'
-require 'models/organization'
-require 'models/guitar'
-require 'models/tuning_peg'
+# frozen_string_literal: true
+
+require "cases/helper"
+require "models/bird"
+require "models/post"
+require "models/comment"
+require "models/company"
+require "models/contract"
+require "models/customer"
+require "models/developer"
+require "models/computer"
+require "models/invoice"
+require "models/line_item"
+require "models/order"
+require "models/parrot"
+require "models/pirate"
+require "models/ship"
+require "models/ship_part"
+require "models/tag"
+require "models/tagging"
+require "models/treasure"
+require "models/eye"
+require "models/electron"
+require "models/molecule"
+require "models/member"
+require "models/member_detail"
+require "models/organization"
+require "models/guitar"
+require "models/tuning_peg"
 
 class TestAutosaveAssociationsInGeneral < ActiveRecord::TestCase
   def test_autosave_validation
     person = Class.new(ActiveRecord::Base) {
-      self.table_name = 'people'
-      validate :should_be_cool, :on => :create
-      def self.name; 'Person'; end
+      self.table_name = "people"
+      validate :should_be_cool, on: :create
+      def self.name; "Person"; end
 
       private
 
-      def should_be_cool
-        unless self.first_name == 'cool'
-          errors.add :first_name, "not cool"
+        def should_be_cool
+          unless first_name == "cool"
+            errors.add :first_name, "not cool"
+          end
         end
-      end
     }
     reference = Class.new(ActiveRecord::Base) {
       self.table_name = "references"
-      def self.name; 'Reference'; end
+      def self.name; "Reference"; end
       belongs_to :person, autosave: true, anonymous_class: person
     }
 
-    u = person.create!(first_name: 'cool')
-    u.update_attributes!(first_name: 'nah') # still valid because validation only applies on 'create'
+    u = person.create!(first_name: "cool")
+    u.update_attributes!(first_name: "nah") # still valid because validation only applies on 'create'
     assert reference.create!(person: u).persisted?
   end
 
@@ -79,25 +80,25 @@ class TestAutosaveAssociationsInGeneral < ActiveRecord::TestCase
 
   private
 
-  def assert_no_difference_when_adding_callbacks_twice_for(model, association_name)
-    reflection = model.reflect_on_association(association_name)
-    assert_no_difference "callbacks_for_model(#{model.name}).length" do
-      model.send(:add_autosave_association_callbacks, reflection)
+    def assert_no_difference_when_adding_callbacks_twice_for(model, association_name)
+      reflection = model.reflect_on_association(association_name)
+      assert_no_difference "callbacks_for_model(#{model.name}).length" do
+        model.send(:add_autosave_association_callbacks, reflection)
+      end
     end
-  end
 
-  def callbacks_for_model(model)
-    model.instance_variables.grep(/_callbacks$/).flat_map do |ivar|
-      model.instance_variable_get(ivar)
+    def callbacks_for_model(model)
+      model.instance_variables.grep(/_callbacks$/).flat_map do |ivar|
+        model.instance_variable_get(ivar)
+      end
     end
-  end
 end
 
 class TestDefaultAutosaveAssociationOnAHasOneAssociation < ActiveRecord::TestCase
   fixtures :companies, :accounts
 
   def test_should_save_parent_but_not_invalid_child
-    firm = Firm.new(:name => 'GlobalMegaCorp')
+    firm = Firm.new(name: "GlobalMegaCorp")
     assert firm.valid?
 
     firm.build_account_using_primary_key
@@ -178,8 +179,8 @@ class TestDefaultAutosaveAssociationOnAHasOneAssociation < ActiveRecord::TestCas
   end
 
   def test_not_resaved_when_unchanged
-    firm = Firm.all.merge!(:includes => :account).first
-    firm.name += '-changed'
+    firm = Firm.all.merge!(includes: :account).first
+    firm.name += "-changed"
     assert_queries(1) { firm.save! }
 
     firm = Firm.first
@@ -196,21 +197,21 @@ class TestDefaultAutosaveAssociationOnAHasOneAssociation < ActiveRecord::TestCas
   end
 
   def test_callbacks_firing_order_on_create
-    eye = Eye.create(:iris_attributes => {:color => 'honey'})
+    eye = Eye.create(iris_attributes: { color: "honey" })
     assert_equal [true, false], eye.after_create_callbacks_stack
   end
 
   def test_callbacks_firing_order_on_update
-    eye = Eye.create(iris_attributes: {color: 'honey'})
-    eye.update(iris_attributes: {color: 'green'})
+    eye = Eye.create(iris_attributes: { color: "honey" })
+    eye.update(iris_attributes: { color: "green" })
     assert_equal [true, false], eye.after_update_callbacks_stack
   end
 
   def test_callbacks_firing_order_on_save
-    eye = Eye.create(iris_attributes: {color: 'honey'})
+    eye = Eye.create(iris_attributes: { color: "honey" })
     assert_equal [false, false], eye.after_save_callbacks_stack
 
-    eye.update(iris_attributes: {color: 'blue'})
+    eye.update(iris_attributes: { color: "blue" })
     assert_equal [false, false, false, false], eye.after_save_callbacks_stack
   end
 end
@@ -219,7 +220,7 @@ class TestDefaultAutosaveAssociationOnABelongsToAssociation < ActiveRecord::Test
   fixtures :companies, :posts, :tags, :taggings
 
   def test_should_save_parent_but_not_invalid_child
-    client = Client.new(:name => 'Joe (the Plumber)')
+    client = Client.new(name: "Joe (the Plumber)")
     assert client.valid?
 
     client.build_firm
@@ -231,7 +232,7 @@ class TestDefaultAutosaveAssociationOnABelongsToAssociation < ActiveRecord::Test
 
   def test_save_fails_for_invalid_belongs_to
     # Oracle saves empty string as NULL therefore :message changed to one space
-    assert log = AuditLog.create(:developer_id => 0, :message => " ")
+    assert log = AuditLog.create(developer_id: 0, message: " ")
 
     log.developer = Developer.new
     assert !log.developer.valid?
@@ -242,7 +243,7 @@ class TestDefaultAutosaveAssociationOnABelongsToAssociation < ActiveRecord::Test
 
   def test_save_succeeds_for_invalid_belongs_to_with_validate_false
     # Oracle saves empty string as NULL therefore :message changed to one space
-    assert log = AuditLog.create(:developer_id => 0, :message=> " ")
+    assert log = AuditLog.create(developer_id: 0, message: " ")
 
     log.unvalidated_developer = Developer.new
     assert !log.unvalidated_developer.valid?
@@ -362,22 +363,22 @@ class TestDefaultAutosaveAssociationOnABelongsToAssociation < ActiveRecord::Test
 
   def test_store_association_with_a_polymorphic_relationship
     num_tagging = Tagging.count
-    tags(:misc).create_tagging(:taggable => posts(:thinking))
+    tags(:misc).create_tagging(taggable: posts(:thinking))
     assert_equal num_tagging + 1, Tagging.count
   end
 
   def test_build_and_then_save_parent_should_not_reload_target
     client = Client.first
-    apple = client.build_firm(:name => "Apple")
+    apple = client.build_firm(name: "Apple")
     client.save!
     assert_no_queries { assert_equal apple, client.firm }
   end
 
   def test_validation_does_not_validate_stale_association_target
-    valid_developer   = Developer.create!(:name => "Dude", :salary => 50_000)
+    valid_developer   = Developer.create!(name: "Dude", salary: 50_000)
     invalid_developer = Developer.new()
 
-    auditlog = AuditLog.new(:message => "foo")
+    auditlog = AuditLog.new(message: "foo")
     auditlog.developer    = invalid_developer
     auditlog.developer_id = valid_developer.id
 
@@ -388,7 +389,7 @@ end
 class TestDefaultAutosaveAssociationOnAHasManyAssociationWithAcceptsNestedAttributes < ActiveRecord::TestCase
   def test_invalid_adding_with_nested_attributes
     molecule = Molecule.new
-    valid_electron = Electron.new(name: 'electron')
+    valid_electron = Electron.new(name: "electron")
     invalid_electron = Electron.new
 
     molecule.electrons = [valid_electron, invalid_electron]
@@ -396,7 +397,7 @@ class TestDefaultAutosaveAssociationOnAHasManyAssociationWithAcceptsNestedAttrib
 
     assert_not invalid_electron.valid?
     assert valid_electron.valid?
-    assert_not molecule.persisted?, 'Molecule should not be persisted when its electrons are invalid'
+    assert_not molecule.persisted?, "Molecule should not be persisted when its electrons are invalid"
   end
 
   def test_errors_should_be_indexed_when_passed_as_array
@@ -419,7 +420,7 @@ class TestDefaultAutosaveAssociationOnAHasManyAssociationWithAcceptsNestedAttrib
     ActiveRecord::Base.index_nested_attribute_errors = true
 
     molecule = Molecule.new
-    valid_electron = Electron.new(name: 'electron')
+    valid_electron = Electron.new(name: "electron")
     invalid_electron = Electron.new
 
     molecule.electrons = [valid_electron, invalid_electron]
@@ -435,7 +436,7 @@ class TestDefaultAutosaveAssociationOnAHasManyAssociationWithAcceptsNestedAttrib
 
   def test_errors_details_should_be_set
     molecule = Molecule.new
-    valid_electron = Electron.new(name: 'electron')
+    valid_electron = Electron.new(name: "electron")
     invalid_electron = Electron.new
 
     molecule.electrons = [valid_electron, invalid_electron]
@@ -443,7 +444,7 @@ class TestDefaultAutosaveAssociationOnAHasManyAssociationWithAcceptsNestedAttrib
     assert_not invalid_electron.valid?
     assert valid_electron.valid?
     assert_not molecule.valid?
-    assert_equal [{error: :blank}], molecule.errors.details["electrons.name"]
+    assert_equal [{ error: :blank }], molecule.errors.details[:"electrons.name"]
   end
 
   def test_errors_details_should_be_indexed_when_passed_as_array
@@ -457,8 +458,8 @@ class TestDefaultAutosaveAssociationOnAHasManyAssociationWithAcceptsNestedAttrib
     assert_not tuning_peg_invalid.valid?
     assert tuning_peg_valid.valid?
     assert_not guitar.valid?
-    assert_equal [{error: :not_a_number, value: nil}] , guitar.errors.details["tuning_pegs[1].pitch"]
-    assert_equal [], guitar.errors.details["tuning_pegs.pitch"]
+    assert_equal [{ error: :not_a_number, value: nil }], guitar.errors.details[:"tuning_pegs[1].pitch"]
+    assert_equal [], guitar.errors.details[:"tuning_pegs.pitch"]
   end
 
   def test_errors_details_should_be_indexed_when_global_flag_is_set
@@ -466,7 +467,7 @@ class TestDefaultAutosaveAssociationOnAHasManyAssociationWithAcceptsNestedAttrib
     ActiveRecord::Base.index_nested_attribute_errors = true
 
     molecule = Molecule.new
-    valid_electron = Electron.new(name: 'electron')
+    valid_electron = Electron.new(name: "electron")
     invalid_electron = Electron.new
 
     molecule.electrons = [valid_electron, invalid_electron]
@@ -474,15 +475,15 @@ class TestDefaultAutosaveAssociationOnAHasManyAssociationWithAcceptsNestedAttrib
     assert_not invalid_electron.valid?
     assert valid_electron.valid?
     assert_not molecule.valid?
-    assert_equal [{error: :blank}], molecule.errors.details["electrons[1].name"]
-    assert_equal [], molecule.errors.details["electrons.name"]
+    assert_equal [{ error: :blank }], molecule.errors.details[:"electrons[1].name"]
+    assert_equal [], molecule.errors.details[:"electrons.name"]
   ensure
     ActiveRecord::Base.index_nested_attribute_errors = old_attribute_config
   end
 
   def test_valid_adding_with_nested_attributes
     molecule = Molecule.new
-    valid_electron = Electron.new(name: 'electron')
+    valid_electron = Electron.new(name: "electron")
 
     molecule.electrons = [valid_electron]
     molecule.save
@@ -494,7 +495,7 @@ class TestDefaultAutosaveAssociationOnAHasManyAssociationWithAcceptsNestedAttrib
 end
 
 class TestDefaultAutosaveAssociationOnAHasManyAssociation < ActiveRecord::TestCase
-  fixtures :companies, :people
+  fixtures :companies, :developers
 
   def test_invalid_adding
     firm = Firm.find(1)
@@ -585,16 +586,16 @@ class TestDefaultAutosaveAssociationOnAHasManyAssociation < ActiveRecord::TestCa
     firm.save
     firm.reload
     assert_equal 2, firm.clients.length
-    assert firm.clients.include?(companies(:second_client))
+    assert_includes firm.clients, companies(:second_client)
   end
 
   def test_assign_ids_for_through_a_belongs_to
-    post = Post.new(:title => "Assigning IDs works!", :body => "You heard it here first, folks!")
-    post.person_ids = [people(:david).id, people(:michael).id]
-    post.save
-    post.reload
-    assert_equal 2, post.people.length
-    assert post.people.include?(people(:david))
+    firm = Firm.new("name" => "Apple")
+    firm.developer_ids = [developers(:david).id, developers(:jamis).id]
+    firm.save
+    firm.reload
+    assert_equal 2, firm.developers.length
+    assert_includes firm.developers, developers(:david)
   end
 
   def test_build_before_save
@@ -602,7 +603,7 @@ class TestDefaultAutosaveAssociationOnAHasManyAssociation < ActiveRecord::TestCa
     new_client = assert_no_queries(ignore_none: false) { company.clients_of_firm.build("name" => "Another Client") }
     assert !company.clients_of_firm.loaded?
 
-    company.name += '-changed'
+    company.name += "-changed"
     assert_queries(2) { assert company.save }
     assert new_client.persisted?
     assert_equal 3, company.clients_of_firm.reload.size
@@ -610,19 +611,19 @@ class TestDefaultAutosaveAssociationOnAHasManyAssociation < ActiveRecord::TestCa
 
   def test_build_many_before_save
     company = companies(:first_firm)
-    assert_no_queries(ignore_none: false) { company.clients_of_firm.build([{"name" => "Another Client"}, {"name" => "Another Client II"}]) }
+    assert_no_queries(ignore_none: false) { company.clients_of_firm.build([{ "name" => "Another Client" }, { "name" => "Another Client II" }]) }
 
-    company.name += '-changed'
+    company.name += "-changed"
     assert_queries(3) { assert company.save }
     assert_equal 4, company.clients_of_firm.reload.size
   end
 
   def test_build_via_block_before_save
     company = companies(:first_firm)
-    new_client = assert_no_queries(ignore_none: false) { company.clients_of_firm.build {|client| client.name = "Another Client" } }
+    new_client = assert_no_queries(ignore_none: false) { company.clients_of_firm.build { |client| client.name = "Another Client" } }
     assert !company.clients_of_firm.loaded?
 
-    company.name += '-changed'
+    company.name += "-changed"
     assert_queries(2) { assert company.save }
     assert new_client.persisted?
     assert_equal 3, company.clients_of_firm.reload.size
@@ -631,12 +632,12 @@ class TestDefaultAutosaveAssociationOnAHasManyAssociation < ActiveRecord::TestCa
   def test_build_many_via_block_before_save
     company = companies(:first_firm)
     assert_no_queries(ignore_none: false) do
-      company.clients_of_firm.build([{"name" => "Another Client"}, {"name" => "Another Client II"}]) do |client|
+      company.clients_of_firm.build([{ "name" => "Another Client" }, { "name" => "Another Client II" }]) do |client|
         client.name = "changed"
       end
     end
 
-    company.name += '-changed'
+    company.name += "-changed"
     assert_queries(3) { assert company.save }
     assert_equal 4, company.clients_of_firm.reload.size
   end
@@ -647,7 +648,7 @@ class TestDefaultAutosaveAssociationOnAHasManyAssociation < ActiveRecord::TestCa
     assert firm.save
     firm.reload
     assert_equal 2, firm.clients.length
-    assert firm.clients.include?(Client.find_by_name("New Client"))
+    assert_includes firm.clients, Client.find_by_name("New Client")
   end
 end
 
@@ -715,8 +716,8 @@ class TestDefaultAutosaveAssociationOnNewRecord < ActiveRecord::TestCase
   end
 
   def test_autosave_new_record_with_after_create_callback
-    post = PostWithAfterCreateCallback.new(title: 'Captain Murphy', body: 'is back')
-    post.comments.build(body: 'foo')
+    post = PostWithAfterCreateCallback.new(title: "Captain Murphy", body: "is back")
+    post.comments.build(body: "foo")
     post.save!
 
     assert_not_nil post.author_id
@@ -727,8 +728,8 @@ class TestDestroyAsPartOfAutosaveAssociation < ActiveRecord::TestCase
   self.use_transactional_tests = false
 
   setup do
-    @pirate = Pirate.create(:catchphrase => "Don' botharrr talkin' like one, savvy?")
-    @ship = @pirate.create_ship(:name => 'Nights Dirty Lightning')
+    @pirate = Pirate.create(catchphrase: "Don' botharrr talkin' like one, savvy?")
+    @ship = @pirate.create_ship(name: "Nights Dirty Lightning")
   end
 
   teardown do
@@ -764,12 +765,12 @@ class TestDestroyAsPartOfAutosaveAssociation < ActiveRecord::TestCase
   end
 
   def test_should_skip_validation_on_a_child_association_if_marked_for_destruction
-    @pirate.ship.name = ''
+    @pirate.ship.name = ""
     assert !@pirate.valid?
 
     @pirate.ship.mark_for_destruction
     @pirate.ship.expects(:valid?).never
-    assert_difference('Ship.count', -1) { @pirate.save! }
+    assert_difference("Ship.count", -1) { @pirate.save! }
   end
 
   def test_a_child_marked_for_destruction_should_not_be_destroyed_twice
@@ -787,11 +788,12 @@ class TestDestroyAsPartOfAutosaveAssociation < ActiveRecord::TestCase
       def save(*args)
         super
         destroy
-        raise 'Oh noes!'
+        raise "Oh noes!"
       end
     end
 
     @ship.pirate.catchphrase = "Changed Catchphrase"
+    @ship.name_will_change!
 
     assert_raise(RuntimeError) { assert !@pirate.save }
     assert_not_nil @pirate.reload.ship
@@ -824,12 +826,12 @@ class TestDestroyAsPartOfAutosaveAssociation < ActiveRecord::TestCase
   end
 
   def test_should_skip_validation_on_a_parent_association_if_marked_for_destruction
-    @ship.pirate.catchphrase = ''
+    @ship.pirate.catchphrase = ""
     assert !@ship.valid?
 
     @ship.pirate.mark_for_destruction
     @ship.pirate.expects(:valid?).never
-    assert_difference('Pirate.count', -1) { @ship.save! }
+    assert_difference("Pirate.count", -1) { @ship.save! }
   end
 
   def test_a_parent_marked_for_destruction_should_not_be_destroyed_twice
@@ -847,7 +849,7 @@ class TestDestroyAsPartOfAutosaveAssociation < ActiveRecord::TestCase
       def save(*args)
         super
         destroy
-        raise 'Oh noes!'
+        raise "Oh noes!"
       end
     end
 
@@ -858,16 +860,16 @@ class TestDestroyAsPartOfAutosaveAssociation < ActiveRecord::TestCase
   end
 
   def test_should_save_changed_child_objects_if_parent_is_saved
-    @pirate = @ship.create_pirate(:catchphrase => "Don' botharrr talkin' like one, savvy?")
-    @parrot = @pirate.parrots.create!(:name => 'Posideons Killer')
+    @pirate = @ship.create_pirate(catchphrase: "Don' botharrr talkin' like one, savvy?")
+    @parrot = @pirate.parrots.create!(name: "Posideons Killer")
     @parrot.name = "NewName"
     @ship.save
 
-    assert_equal 'NewName', @parrot.reload.name
+    assert_equal "NewName", @parrot.reload.name
   end
 
   def test_should_destroy_has_many_as_part_of_the_save_transaction_if_they_were_marked_for_destruction
-    2.times { |i| @pirate.birds.create!(:name => "birds_#{i}") }
+    2.times { |i| @pirate.birds.create!(name: "birds_#{i}") }
 
     assert !@pirate.birds.any?(&:marked_for_destruction?)
 
@@ -891,9 +893,9 @@ class TestDestroyAsPartOfAutosaveAssociation < ActiveRecord::TestCase
   end
 
   def test_should_skip_validation_on_has_many_if_marked_for_destruction
-    2.times { |i| @pirate.birds.create!(:name => "birds_#{i}") }
+    2.times { |i| @pirate.birds.create!(name: "birds_#{i}") }
 
-    @pirate.birds.each { |bird| bird.name = '' }
+    @pirate.birds.each { |bird| bird.name = "" }
     assert !@pirate.valid?
 
     @pirate.birds.each do |bird|
@@ -904,9 +906,9 @@ class TestDestroyAsPartOfAutosaveAssociation < ActiveRecord::TestCase
   end
 
   def test_should_skip_validation_on_has_many_if_destroyed
-    @pirate.birds.create!(:name => "birds_1")
+    @pirate.birds.create!(name: "birds_1")
 
-    @pirate.birds.each { |bird| bird.name = '' }
+    @pirate.birds.each { |bird| bird.name = "" }
     assert !@pirate.valid?
 
     @pirate.birds.each(&:destroy)
@@ -914,7 +916,7 @@ class TestDestroyAsPartOfAutosaveAssociation < ActiveRecord::TestCase
   end
 
   def test_a_child_marked_for_destruction_should_not_be_destroyed_twice_while_saving_has_many
-    @pirate.birds.create!(:name => "birds_1")
+    @pirate.birds.create!(name: "birds_1")
 
     @pirate.birds.each(&:mark_for_destruction)
     assert @pirate.save
@@ -924,14 +926,14 @@ class TestDestroyAsPartOfAutosaveAssociation < ActiveRecord::TestCase
   end
 
   def test_should_rollback_destructions_if_an_exception_occurred_while_saving_has_many
-    2.times { |i| @pirate.birds.create!(:name => "birds_#{i}") }
+    2.times { |i| @pirate.birds.create!(name: "birds_#{i}") }
     before = @pirate.birds.map { |c| c.mark_for_destruction ; c }
 
     # Stub the destroy method of the second child to raise an exception
     class << before.last
       def destroy(*args)
         super
-        raise 'Oh noes!'
+        raise "Oh noes!"
       end
     end
 
@@ -940,9 +942,9 @@ class TestDestroyAsPartOfAutosaveAssociation < ActiveRecord::TestCase
   end
 
   def test_when_new_record_a_child_marked_for_destruction_should_not_affect_other_records_from_saving
-    @pirate = @ship.build_pirate(:catchphrase => "Arr' now I shall keep me eye on you matey!") # new record
+    @pirate = @ship.build_pirate(catchphrase: "Arr' now I shall keep me eye on you matey!") # new record
 
-    3.times { |i| @pirate.birds.build(:name => "birds_#{i}") }
+    3.times { |i| @pirate.birds.build(name: "birds_#{i}") }
     @pirate.birds[1].mark_for_destruction
     @pirate.save!
 
@@ -968,8 +970,8 @@ class TestDestroyAsPartOfAutosaveAssociation < ActiveRecord::TestCase
     define_method("test_should_run_add_callback_#{callback_type}s_for_has_many") do
       association_name_with_callbacks = "birds_with_#{callback_type}_callbacks"
 
-      pirate = Pirate.new(:catchphrase => "Arr")
-      pirate.send(association_name_with_callbacks).build(:name => "Crowe the One-Eyed")
+      pirate = Pirate.new(catchphrase: "Arr")
+      pirate.send(association_name_with_callbacks).build(name: "Crowe the One-Eyed")
 
       expected = [
         "before_adding_#{callback_type}_bird_<new>",
@@ -982,7 +984,7 @@ class TestDestroyAsPartOfAutosaveAssociation < ActiveRecord::TestCase
     define_method("test_should_run_remove_callback_#{callback_type}s_for_has_many") do
       association_name_with_callbacks = "birds_with_#{callback_type}_callbacks"
 
-      @pirate.send(association_name_with_callbacks).create!(:name => "Crowe the One-Eyed")
+      @pirate.send(association_name_with_callbacks).create!(name: "Crowe the One-Eyed")
       @pirate.send(association_name_with_callbacks).each(&:mark_for_destruction)
       child_id = @pirate.send(association_name_with_callbacks).first.id
 
@@ -999,7 +1001,7 @@ class TestDestroyAsPartOfAutosaveAssociation < ActiveRecord::TestCase
   end
 
   def test_should_destroy_habtm_as_part_of_the_save_transaction_if_they_were_marked_for_destruction
-    2.times { |i| @pirate.parrots.create!(:name => "parrots_#{i}") }
+    2.times { |i| @pirate.parrots.create!(name: "parrots_#{i}") }
 
     assert !@pirate.parrots.any?(&:marked_for_destruction?)
     @pirate.parrots.each(&:mark_for_destruction)
@@ -1015,9 +1017,9 @@ class TestDestroyAsPartOfAutosaveAssociation < ActiveRecord::TestCase
   end
 
   def test_should_skip_validation_on_habtm_if_marked_for_destruction
-    2.times { |i| @pirate.parrots.create!(:name => "parrots_#{i}") }
+    2.times { |i| @pirate.parrots.create!(name: "parrots_#{i}") }
 
-    @pirate.parrots.each { |parrot| parrot.name = '' }
+    @pirate.parrots.each { |parrot| parrot.name = "" }
     assert !@pirate.valid?
 
     @pirate.parrots.each do |parrot|
@@ -1030,9 +1032,9 @@ class TestDestroyAsPartOfAutosaveAssociation < ActiveRecord::TestCase
   end
 
   def test_should_skip_validation_on_habtm_if_destroyed
-    @pirate.parrots.create!(:name => "parrots_1")
+    @pirate.parrots.create!(name: "parrots_1")
 
-    @pirate.parrots.each { |parrot| parrot.name = '' }
+    @pirate.parrots.each { |parrot| parrot.name = "" }
     assert !@pirate.valid?
 
     @pirate.parrots.each(&:destroy)
@@ -1040,7 +1042,7 @@ class TestDestroyAsPartOfAutosaveAssociation < ActiveRecord::TestCase
   end
 
   def test_a_child_marked_for_destruction_should_not_be_destroyed_twice_while_saving_habtm
-    @pirate.parrots.create!(:name => "parrots_1")
+    @pirate.parrots.create!(name: "parrots_1")
 
     @pirate.parrots.each(&:mark_for_destruction)
     assert @pirate.save
@@ -1053,13 +1055,13 @@ class TestDestroyAsPartOfAutosaveAssociation < ActiveRecord::TestCase
   end
 
   def test_should_rollback_destructions_if_an_exception_occurred_while_saving_habtm
-    2.times { |i| @pirate.parrots.create!(:name => "parrots_#{i}") }
+    2.times { |i| @pirate.parrots.create!(name: "parrots_#{i}") }
     before = @pirate.parrots.map { |c| c.mark_for_destruction ; c }
 
     class << @pirate.association(:parrots)
       def destroy(*args)
         super
-        raise 'Oh noes!'
+        raise "Oh noes!"
       end
     end
 
@@ -1072,8 +1074,8 @@ class TestDestroyAsPartOfAutosaveAssociation < ActiveRecord::TestCase
     define_method("test_should_run_add_callback_#{callback_type}s_for_habtm") do
       association_name_with_callbacks = "parrots_with_#{callback_type}_callbacks"
 
-      pirate = Pirate.new(:catchphrase => "Arr")
-      pirate.send(association_name_with_callbacks).build(:name => "Crowe the One-Eyed")
+      pirate = Pirate.new(catchphrase: "Arr")
+      pirate.send(association_name_with_callbacks).build(name: "Crowe the One-Eyed")
 
       expected = [
         "before_adding_#{callback_type}_parrot_<new>",
@@ -1086,7 +1088,7 @@ class TestDestroyAsPartOfAutosaveAssociation < ActiveRecord::TestCase
     define_method("test_should_run_remove_callback_#{callback_type}s_for_habtm") do
       association_name_with_callbacks = "parrots_with_#{callback_type}_callbacks"
 
-      @pirate.send(association_name_with_callbacks).create!(:name => "Crowe the One-Eyed")
+      @pirate.send(association_name_with_callbacks).create!(name: "Crowe the One-Eyed")
       @pirate.send(association_name_with_callbacks).each(&:mark_for_destruction)
       child_id = @pirate.send(association_name_with_callbacks).first.id
 
@@ -1108,21 +1110,21 @@ class TestAutosaveAssociationOnAHasOneAssociation < ActiveRecord::TestCase
 
   def setup
     super
-    @pirate = Pirate.create(:catchphrase => "Don' botharrr talkin' like one, savvy?")
-    @ship = @pirate.create_ship(:name => 'Nights Dirty Lightning')
+    @pirate = Pirate.create(catchphrase: "Don' botharrr talkin' like one, savvy?")
+    @ship = @pirate.create_ship(name: "Nights Dirty Lightning")
   end
 
   def test_should_still_work_without_an_associated_model
     @ship.destroy
     @pirate.reload.catchphrase = "Arr"
     @pirate.save
-    assert_equal 'Arr', @pirate.reload.catchphrase
+    assert_equal "Arr", @pirate.reload.catchphrase
   end
 
   def test_should_automatically_save_the_associated_model
-    @pirate.ship.name = 'The Vile Insanity'
+    @pirate.ship.name = "The Vile Insanity"
     @pirate.save
-    assert_equal 'The Vile Insanity', @pirate.reload.ship.name
+    assert_equal "The Vile Insanity", @pirate.reload.ship.name
   end
 
   def test_changed_for_autosave_should_handle_cycles
@@ -1130,19 +1132,19 @@ class TestAutosaveAssociationOnAHasOneAssociation < ActiveRecord::TestCase
     assert_queries(0) { @ship.save! }
 
     @parrot = @pirate.parrots.create(name: "some_name")
-    @parrot.name="changed_name"
+    @parrot.name = "changed_name"
     assert_queries(1) { @ship.save! }
     assert_queries(0) { @ship.save! }
   end
 
   def test_should_automatically_save_bang_the_associated_model
-    @pirate.ship.name = 'The Vile Insanity'
+    @pirate.ship.name = "The Vile Insanity"
     @pirate.save!
-    assert_equal 'The Vile Insanity', @pirate.reload.ship.name
+    assert_equal "The Vile Insanity", @pirate.reload.ship.name
   end
 
   def test_should_automatically_validate_the_associated_model
-    @pirate.ship.name = ''
+    @pirate.ship.name = ""
     assert @pirate.invalid?
     assert @pirate.errors[:"ship.name"].any?
   end
@@ -1158,7 +1160,7 @@ class TestAutosaveAssociationOnAHasOneAssociation < ActiveRecord::TestCase
   def test_should_not_ignore_different_error_messages_on_the_same_attribute
     old_validators = Ship._validators.deep_dup
     old_callbacks = Ship._validate_callbacks.deep_dup
-    Ship.validates_format_of :name, :with => /\w/
+    Ship.validates_format_of :name, with: /\w/
     @pirate.ship.name   = ""
     @pirate.catchphrase = nil
     assert @pirate.invalid?
@@ -1169,48 +1171,48 @@ class TestAutosaveAssociationOnAHasOneAssociation < ActiveRecord::TestCase
   end
 
   def test_should_still_allow_to_bypass_validations_on_the_associated_model
-    @pirate.catchphrase = ''
-    @pirate.ship.name = ''
-    @pirate.save(:validate => false)
+    @pirate.catchphrase = ""
+    @pirate.ship.name = ""
+    @pirate.save(validate: false)
     # Oracle saves empty string as NULL
     if current_adapter?(:OracleAdapter)
       assert_equal [nil, nil], [@pirate.reload.catchphrase, @pirate.ship.name]
     else
-      assert_equal ['', ''], [@pirate.reload.catchphrase, @pirate.ship.name]
+      assert_equal ["", ""], [@pirate.reload.catchphrase, @pirate.ship.name]
     end
   end
 
   def test_should_allow_to_bypass_validations_on_associated_models_at_any_depth
-    2.times { |i| @pirate.ship.parts.create!(:name => "part #{i}") }
+    2.times { |i| @pirate.ship.parts.create!(name: "part #{i}") }
 
-    @pirate.catchphrase = ''
-    @pirate.ship.name = ''
-    @pirate.ship.parts.each { |part| part.name = '' }
-    @pirate.save(:validate => false)
+    @pirate.catchphrase = ""
+    @pirate.ship.name = ""
+    @pirate.ship.parts.each { |part| part.name = "" }
+    @pirate.save(validate: false)
 
     values = [@pirate.reload.catchphrase, @pirate.ship.name, *@pirate.ship.parts.map(&:name)]
     # Oracle saves empty string as NULL
     if current_adapter?(:OracleAdapter)
       assert_equal [nil, nil, nil, nil], values
     else
-      assert_equal ['', '', '', ''], values
+      assert_equal ["", "", "", ""], values
     end
   end
 
   def test_should_still_raise_an_ActiveRecordRecord_Invalid_exception_if_we_want_that
-    @pirate.ship.name = ''
+    @pirate.ship.name = ""
     assert_raise(ActiveRecord::RecordInvalid) do
       @pirate.save!
     end
   end
 
   def test_should_not_save_and_return_false_if_a_callback_cancelled_saving
-    pirate = Pirate.new(:catchphrase => 'Arr')
-    ship = pirate.build_ship(:name => 'The Vile Insanity')
+    pirate = Pirate.new(catchphrase: "Arr")
+    ship = pirate.build_ship(name: "The Vile Insanity")
     ship.cancel_save_from_callback = true
 
-    assert_no_difference 'Pirate.count' do
-      assert_no_difference 'Ship.count' do
+    assert_no_difference "Pirate.count" do
+      assert_no_difference "Ship.count" do
         assert !pirate.save
       end
     end
@@ -1219,14 +1221,14 @@ class TestAutosaveAssociationOnAHasOneAssociation < ActiveRecord::TestCase
   def test_should_rollback_any_changes_if_an_exception_occurred_while_saving
     before = [@pirate.catchphrase, @pirate.ship.name]
 
-    @pirate.catchphrase = 'Arr'
-    @pirate.ship.name = 'The Vile Insanity'
+    @pirate.catchphrase = "Arr"
+    @pirate.ship.name = "The Vile Insanity"
 
     # Stub the save method of the @pirate.ship instance to raise an exception
     class << @pirate.ship
       def save(*args)
         super
-        raise 'Oh noes!'
+        raise "Oh noes!"
       end
     end
 
@@ -1235,7 +1237,7 @@ class TestAutosaveAssociationOnAHasOneAssociation < ActiveRecord::TestCase
   end
 
   def test_should_not_load_the_associated_model
-    assert_queries(1) { @pirate.catchphrase = 'Arr'; @pirate.save! }
+    assert_queries(1) { @pirate.catchphrase = "Arr"; @pirate.save! }
   end
 
   def test_mark_for_destruction_is_ignored_without_autosave_true
@@ -1260,7 +1262,7 @@ class TestAutosaveAssociationOnAHasOneThroughAssociation < ActiveRecord::TestCas
     class << @member.organization
       def save(*args)
         super
-        raise 'Oh noes!'
+        raise "Oh noes!"
       end
     end
     assert_nothing_raised { @member.save }
@@ -1272,31 +1274,31 @@ class TestAutosaveAssociationOnABelongsToAssociation < ActiveRecord::TestCase
 
   def setup
     super
-    @ship = Ship.create(:name => 'Nights Dirty Lightning')
-    @pirate = @ship.create_pirate(:catchphrase => "Don' botharrr talkin' like one, savvy?")
+    @ship = Ship.create(name: "Nights Dirty Lightning")
+    @pirate = @ship.create_pirate(catchphrase: "Don' botharrr talkin' like one, savvy?")
   end
 
   def test_should_still_work_without_an_associated_model
     @pirate.destroy
     @ship.reload.name = "The Vile Insanity"
     @ship.save
-    assert_equal 'The Vile Insanity', @ship.reload.name
+    assert_equal "The Vile Insanity", @ship.reload.name
   end
 
   def test_should_automatically_save_the_associated_model
-    @ship.pirate.catchphrase = 'Arr'
+    @ship.pirate.catchphrase = "Arr"
     @ship.save
-    assert_equal 'Arr', @ship.reload.pirate.catchphrase
+    assert_equal "Arr", @ship.reload.pirate.catchphrase
   end
 
   def test_should_automatically_save_bang_the_associated_model
-    @ship.pirate.catchphrase = 'Arr'
+    @ship.pirate.catchphrase = "Arr"
     @ship.save!
-    assert_equal 'Arr', @ship.reload.pirate.catchphrase
+    assert_equal "Arr", @ship.reload.pirate.catchphrase
   end
 
   def test_should_automatically_validate_the_associated_model
-    @ship.pirate.catchphrase = ''
+    @ship.pirate.catchphrase = ""
     assert @ship.invalid?
     assert @ship.errors[:"pirate.catchphrase"].any?
   end
@@ -1310,31 +1312,31 @@ class TestAutosaveAssociationOnABelongsToAssociation < ActiveRecord::TestCase
   end
 
   def test_should_still_allow_to_bypass_validations_on_the_associated_model
-    @ship.pirate.catchphrase = ''
-    @ship.name = ''
-    @ship.save(:validate => false)
+    @ship.pirate.catchphrase = ""
+    @ship.name = ""
+    @ship.save(validate: false)
     # Oracle saves empty string as NULL
     if current_adapter?(:OracleAdapter)
       assert_equal [nil, nil], [@ship.reload.name, @ship.pirate.catchphrase]
     else
-      assert_equal ['', ''], [@ship.reload.name, @ship.pirate.catchphrase]
+      assert_equal ["", ""], [@ship.reload.name, @ship.pirate.catchphrase]
     end
   end
 
   def test_should_still_raise_an_ActiveRecordRecord_Invalid_exception_if_we_want_that
-    @ship.pirate.catchphrase = ''
+    @ship.pirate.catchphrase = ""
     assert_raise(ActiveRecord::RecordInvalid) do
       @ship.save!
     end
   end
 
   def test_should_not_save_and_return_false_if_a_callback_cancelled_saving
-    ship = Ship.new(:name => 'The Vile Insanity')
-    pirate = ship.build_pirate(:catchphrase => 'Arr')
+    ship = Ship.new(name: "The Vile Insanity")
+    pirate = ship.build_pirate(catchphrase: "Arr")
     pirate.cancel_save_from_callback = true
 
-    assert_no_difference 'Ship.count' do
-      assert_no_difference 'Pirate.count' do
+    assert_no_difference "Ship.count" do
+      assert_no_difference "Pirate.count" do
         assert !ship.save
       end
     end
@@ -1343,14 +1345,14 @@ class TestAutosaveAssociationOnABelongsToAssociation < ActiveRecord::TestCase
   def test_should_rollback_any_changes_if_an_exception_occurred_while_saving
     before = [@ship.pirate.catchphrase, @ship.name]
 
-    @ship.pirate.catchphrase = 'Arr'
-    @ship.name = 'The Vile Insanity'
+    @ship.pirate.catchphrase = "Arr"
+    @ship.name = "The Vile Insanity"
 
     # Stub the save method of the @ship.pirate instance to raise an exception
     class << @ship.pirate
       def save(*args)
         super
-        raise 'Oh noes!'
+        raise "Oh noes!"
       end
     end
 
@@ -1359,25 +1361,25 @@ class TestAutosaveAssociationOnABelongsToAssociation < ActiveRecord::TestCase
   end
 
   def test_should_not_load_the_associated_model
-    assert_queries(1) { @ship.name = 'The Vile Insanity'; @ship.save! }
+    assert_queries(1) { @ship.name = "The Vile Insanity"; @ship.save! }
   end
 end
 
 module AutosaveAssociationOnACollectionAssociationTests
   def test_should_automatically_save_the_associated_models
-    new_names = ['Grace OMalley', 'Privateers Greed']
+    new_names = ["Grace OMalley", "Privateers Greed"]
     @pirate.send(@association_name).each_with_index { |child, i| child.name = new_names[i] }
 
     @pirate.save
-    assert_equal new_names, @pirate.reload.send(@association_name).map(&:name)
+    assert_equal new_names.sort, @pirate.reload.send(@association_name).map(&:name).sort
   end
 
   def test_should_automatically_save_bang_the_associated_models
-    new_names = ['Grace OMalley', 'Privateers Greed']
+    new_names = ["Grace OMalley", "Privateers Greed"]
     @pirate.send(@association_name).each_with_index { |child, i| child.name = new_names[i] }
 
     @pirate.save!
-    assert_equal new_names, @pirate.reload.send(@association_name).map(&:name)
+    assert_equal new_names.sort, @pirate.reload.send(@association_name).map(&:name).sort
   end
 
   def test_should_update_children_when_autosave_is_true_and_parent_is_new_but_child_is_not
@@ -1390,8 +1392,16 @@ module AutosaveAssociationOnACollectionAssociationTests
     assert_equal "Squawky", parrot.reload.name
   end
 
+  def test_should_not_update_children_when_parent_creation_with_no_reason
+    parrot = Parrot.create!(name: "Polly")
+    assert_equal 0, parrot.updated_count
+
+    Pirate.create!(parrot_ids: [parrot.id], catchphrase: "Arrrr")
+    assert_equal 0, parrot.reload.updated_count
+  end
+
   def test_should_automatically_validate_the_associated_models
-    @pirate.send(@association_name).each { |child| child.name = '' }
+    @pirate.send(@association_name).each { |child| child.name = "" }
 
     assert !@pirate.valid?
     assert_equal ["can't be blank"], @pirate.errors["#{@association_name}.name"]
@@ -1399,7 +1409,7 @@ module AutosaveAssociationOnACollectionAssociationTests
   end
 
   def test_should_not_use_default_invalid_error_on_associated_models
-    @pirate.send(@association_name).build(:name => '')
+    @pirate.send(@association_name).build(name: "")
 
     assert !@pirate.valid?
     assert_equal ["can't be blank"], @pirate.errors["#{@association_name}.name"]
@@ -1407,11 +1417,11 @@ module AutosaveAssociationOnACollectionAssociationTests
   end
 
   def test_should_default_invalid_error_from_i18n
-    I18n.backend.store_translations(:en, activerecord: {errors: { models:
+    I18n.backend.store_translations(:en, activerecord: { errors: { models:
       { @associated_model_name.to_s.to_sym => { blank: "cannot be blank" } }
-    }})
+    } })
 
-    @pirate.send(@association_name).build(name: '')
+    @pirate.send(@association_name).build(name: "")
 
     assert !@pirate.valid?
     assert_equal ["cannot be blank"], @pirate.errors["#{@association_name}.name"]
@@ -1422,7 +1432,7 @@ module AutosaveAssociationOnACollectionAssociationTests
   end
 
   def test_should_merge_errors_on_the_associated_models_onto_the_parent_even_if_it_is_not_valid
-    @pirate.send(@association_name).each { |child| child.name = '' }
+    @pirate.send(@association_name).each { |child| child.name = "" }
     @pirate.catchphrase = nil
 
     assert !@pirate.valid?
@@ -1431,10 +1441,10 @@ module AutosaveAssociationOnACollectionAssociationTests
   end
 
   def test_should_allow_to_bypass_validations_on_the_associated_models_on_update
-    @pirate.catchphrase = ''
-    @pirate.send(@association_name).each { |child| child.name = '' }
+    @pirate.catchphrase = ""
+    @pirate.send(@association_name).each { |child| child.name = "" }
 
-    assert @pirate.save(:validate => false)
+    assert @pirate.save(validate: false)
     # Oracle saves empty string as NULL
     if current_adapter?(:OracleAdapter)
       assert_equal [nil, nil, nil], [
@@ -1443,7 +1453,7 @@ module AutosaveAssociationOnACollectionAssociationTests
         @pirate.send(@association_name).last.name
       ]
     else
-      assert_equal ['', '', ''], [
+      assert_equal ["", "", ""], [
         @pirate.reload.catchphrase,
         @pirate.send(@association_name).first.name,
         @pirate.send(@association_name).last.name
@@ -1461,24 +1471,24 @@ module AutosaveAssociationOnACollectionAssociationTests
   def test_should_allow_to_bypass_validations_on_the_associated_models_on_create
     assert_difference("#{ @association_name == :birds ? 'Bird' : 'Parrot' }.count", 2) do
       2.times { @pirate.send(@association_name).build }
-      @pirate.save(:validate => false)
+      @pirate.save(validate: false)
     end
   end
 
   def test_should_not_save_and_return_false_if_a_callback_cancelled_saving_in_either_create_or_update
-    @pirate.catchphrase = 'Changed'
-    @child_1.name = 'Changed'
+    @pirate.catchphrase = "Changed"
+    @child_1.name = "Changed"
     @child_1.cancel_save_from_callback = true
 
     assert !@pirate.save
     assert_equal "Don' botharrr talkin' like one, savvy?", @pirate.reload.catchphrase
     assert_equal "Posideons Killer", @child_1.reload.name
 
-    new_pirate = Pirate.new(:catchphrase => 'Arr')
-    new_child = new_pirate.send(@association_name).build(:name => 'Grace OMalley')
+    new_pirate = Pirate.new(catchphrase: "Arr")
+    new_child = new_pirate.send(@association_name).build(name: "Grace OMalley")
     new_child.cancel_save_from_callback = true
 
-    assert_no_difference 'Pirate.count' do
+    assert_no_difference "Pirate.count" do
       assert_no_difference "#{new_child.class.name}.count" do
         assert !new_pirate.save
       end
@@ -1487,16 +1497,16 @@ module AutosaveAssociationOnACollectionAssociationTests
 
   def test_should_rollback_any_changes_if_an_exception_occurred_while_saving
     before = [@pirate.catchphrase, *@pirate.send(@association_name).map(&:name)]
-    new_names = ['Grace OMalley', 'Privateers Greed']
+    new_names = ["Grace OMalley", "Privateers Greed"]
 
-    @pirate.catchphrase = 'Arr'
+    @pirate.catchphrase = "Arr"
     @pirate.send(@association_name).each_with_index { |child, i| child.name = new_names[i] }
 
     # Stub the save method of the first child instance to raise an exception
     class << @pirate.send(@association_name).first
       def save(*args)
         super
-        raise 'Oh noes!'
+        raise "Oh noes!"
       end
     end
 
@@ -1505,20 +1515,20 @@ module AutosaveAssociationOnACollectionAssociationTests
   end
 
   def test_should_still_raise_an_ActiveRecordRecord_Invalid_exception_if_we_want_that
-    @pirate.send(@association_name).each { |child| child.name = '' }
+    @pirate.send(@association_name).each { |child| child.name = "" }
     assert_raise(ActiveRecord::RecordInvalid) do
       @pirate.save!
     end
   end
 
   def test_should_not_load_the_associated_models_if_they_were_not_loaded_yet
-    assert_queries(1) { @pirate.catchphrase = 'Arr'; @pirate.save! }
+    assert_queries(1) { @pirate.catchphrase = "Arr"; @pirate.save! }
 
     @pirate.send(@association_name).load_target
 
     assert_queries(3) do
-      @pirate.catchphrase = 'Yarr'
-      new_names = ['Grace OMalley', 'Privateers Greed']
+      @pirate.catchphrase = "Yarr"
+      new_names = ["Grace OMalley", "Privateers Greed"]
       @pirate.send(@association_name).each_with_index { |child, i| child.name = new_names[i] }
       @pirate.save!
     end
@@ -1533,9 +1543,9 @@ class TestAutosaveAssociationOnAHasManyAssociation < ActiveRecord::TestCase
     @association_name = :birds
     @associated_model_name = :bird
 
-    @pirate = Pirate.create(:catchphrase => "Don' botharrr talkin' like one, savvy?")
-    @child_1 = @pirate.birds.create(:name => 'Posideons Killer')
-    @child_2 = @pirate.birds.create(:name => 'Killer bandita Dionne')
+    @pirate = Pirate.create(catchphrase: "Don' botharrr talkin' like one, savvy?")
+    @child_1 = @pirate.birds.create(name: "Posideons Killer")
+    @child_2 = @pirate.birds.create(name: "Killer bandita Dionne")
   end
 
   include AutosaveAssociationOnACollectionAssociationTests
@@ -1551,8 +1561,8 @@ class TestAutosaveAssociationOnAHasAndBelongsToManyAssociation < ActiveRecord::T
     @habtm = true
 
     @pirate = Pirate.create(catchphrase: "Don' botharrr talkin' like one, savvy?")
-    @child_1 = @pirate.parrots.create(name: 'Posideons Killer')
-    @child_2 = @pirate.parrots.create(name: 'Killer bandita Dionne')
+    @child_1 = @pirate.parrots.create(name: "Posideons Killer")
+    @child_2 = @pirate.parrots.create(name: "Killer bandita Dionne")
   end
 
   include AutosaveAssociationOnACollectionAssociationTests
@@ -1568,8 +1578,8 @@ class TestAutosaveAssociationOnAHasAndBelongsToManyAssociationWithAcceptsNestedA
     @habtm = true
 
     @pirate = Pirate.create(catchphrase: "Don' botharrr talkin' like one, savvy?")
-    @child_1 = @pirate.parrots.create(name: 'Posideons Killer')
-    @child_2 = @pirate.parrots.create(name: 'Killer bandita Dionne')
+    @child_1 = @pirate.parrots.create(name: "Posideons Killer")
+    @child_2 = @pirate.parrots.create(name: "Killer bandita Dionne")
   end
 
   include AutosaveAssociationOnACollectionAssociationTests
@@ -1580,13 +1590,13 @@ class TestAutosaveAssociationValidationsOnAHasManyAssociation < ActiveRecord::Te
 
   def setup
     super
-    @pirate = Pirate.create(:catchphrase => "Don' botharrr talkin' like one, savvy?")
-    @pirate.birds.create(:name => 'cookoo')
+    @pirate = Pirate.create(catchphrase: "Don' botharrr talkin' like one, savvy?")
+    @pirate.birds.create(name: "cookoo")
   end
 
   test "should automatically validate associations" do
     assert @pirate.valid?
-    @pirate.birds.each { |bird| bird.name = '' }
+    @pirate.birds.each { |bird| bird.name = "" }
 
     assert !@pirate.valid?
   end
@@ -1597,20 +1607,20 @@ class TestAutosaveAssociationValidationsOnAHasOneAssociation < ActiveRecord::Tes
 
   def setup
     super
-    @pirate = Pirate.create(:catchphrase => "Don' botharrr talkin' like one, savvy?")
-    @pirate.create_ship(:name => 'titanic')
+    @pirate = Pirate.create(catchphrase: "Don' botharrr talkin' like one, savvy?")
+    @pirate.create_ship(name: "titanic")
     super
   end
 
   test "should automatically validate associations with :validate => true" do
     assert @pirate.valid?
-    @pirate.ship.name = ''
+    @pirate.ship.name = ""
     assert !@pirate.valid?
   end
 
   test "should not automatically add validate associations without :validate => true" do
     assert @pirate.valid?
-    @pirate.non_validated_ship.name = ''
+    @pirate.non_validated_ship.name = ""
     assert @pirate.valid?
   end
 end
@@ -1620,18 +1630,18 @@ class TestAutosaveAssociationValidationsOnABelongsToAssociation < ActiveRecord::
 
   def setup
     super
-    @pirate = Pirate.create(:catchphrase => "Don' botharrr talkin' like one, savvy?")
+    @pirate = Pirate.create(catchphrase: "Don' botharrr talkin' like one, savvy?")
   end
 
   test "should automatically validate associations with :validate => true" do
     assert @pirate.valid?
-    @pirate.parrot = Parrot.new(:name => '')
+    @pirate.parrot = Parrot.new(name: "")
     assert !@pirate.valid?
   end
 
   test "should not automatically validate associations without :validate => true" do
     assert @pirate.valid?
-    @pirate.non_validated_parrot = Parrot.new(:name => '')
+    @pirate.non_validated_parrot = Parrot.new(name: "")
     assert @pirate.valid?
   end
 end
@@ -1641,20 +1651,20 @@ class TestAutosaveAssociationValidationsOnAHABTMAssociation < ActiveRecord::Test
 
   def setup
     super
-    @pirate = Pirate.create(:catchphrase => "Don' botharrr talkin' like one, savvy?")
+    @pirate = Pirate.create(catchphrase: "Don' botharrr talkin' like one, savvy?")
   end
 
   test "should automatically validate associations with :validate => true" do
     assert @pirate.valid?
-    @pirate.parrots = [ Parrot.new(:name => 'popuga') ]
-    @pirate.parrots.each { |parrot| parrot.name = '' }
+    @pirate.parrots = [ Parrot.new(name: "popuga") ]
+    @pirate.parrots.each { |parrot| parrot.name = "" }
     assert !@pirate.valid?
   end
 
   test "should not automatically validate associations without :validate => true" do
     assert @pirate.valid?
-    @pirate.non_validated_parrots = [ Parrot.new(:name => 'popuga') ]
-    @pirate.non_validated_parrots.each { |parrot| parrot.name = '' }
+    @pirate.non_validated_parrots = [ Parrot.new(name: "popuga") ]
+    @pirate.non_validated_parrots.each { |parrot| parrot.name = "" }
     assert @pirate.valid?
   end
 end
@@ -1695,6 +1705,34 @@ end
 class TestAutosaveAssociationWithTouch < ActiveRecord::TestCase
   def test_autosave_with_touch_should_not_raise_system_stack_error
     invoice = Invoice.create
-    assert_nothing_raised { invoice.line_items.create(:amount => 10) }
+    assert_nothing_raised { invoice.line_items.create(amount: 10) }
+  end
+end
+
+class TestAutosaveAssociationOnAHasManyAssociationWithInverse < ActiveRecord::TestCase
+  class Post < ActiveRecord::Base
+    has_many :comments, inverse_of: :post
+  end
+
+  class Comment < ActiveRecord::Base
+    belongs_to :post, inverse_of: :comments
+
+    attr_accessor :post_comments_count
+    after_save do
+      self.post_comments_count = post.comments.count
+    end
+  end
+
+  def setup
+    Comment.delete_all
+  end
+
+  def test_after_save_callback_with_autosave
+    post = Post.new(title: "Test", body: "...")
+    comment = post.comments.build(body: "...")
+    post.save!
+
+    assert_equal 1, post.comments.count
+    assert_equal 1, comment.post_comments_count
   end
 end
diff --git a/activerecord/test/cases/base_test.rb b/activerecord/test/cases/base_test.rb
index 00e4e50ea1..a49990008c 100644
--- a/activerecord/test/cases/base_test.rb
+++ b/activerecord/test/cases/base_test.rb
@@ -1,30 +1,33 @@
+# frozen_string_literal: true
+
 require "cases/helper"
-require 'models/post'
-require 'models/author'
-require 'models/topic'
-require 'models/reply'
-require 'models/category'
-require 'models/company'
-require 'models/customer'
-require 'models/developer'
-require 'models/computer'
-require 'models/project'
-require 'models/default'
-require 'models/auto_id'
-require 'models/boolean'
-require 'models/column_name'
-require 'models/subscriber'
-require 'models/comment'
-require 'models/minimalistic'
-require 'models/warehouse_thing'
-require 'models/parrot'
-require 'models/person'
-require 'models/edge'
-require 'models/joke'
-require 'models/bird'
-require 'models/car'
-require 'models/bulb'
-require 'concurrent/atomic/count_down_latch'
+require "models/post"
+require "models/author"
+require "models/topic"
+require "models/reply"
+require "models/category"
+require "models/categorization"
+require "models/company"
+require "models/customer"
+require "models/developer"
+require "models/computer"
+require "models/project"
+require "models/default"
+require "models/auto_id"
+require "models/boolean"
+require "models/column_name"
+require "models/subscriber"
+require "models/comment"
+require "models/minimalistic"
+require "models/warehouse_thing"
+require "models/parrot"
+require "models/person"
+require "models/edge"
+require "models/joke"
+require "models/bird"
+require "models/car"
+require "models/bulb"
+require "concurrent/atomic/count_down_latch"
 
 class FirstAbstractClass < ActiveRecord::Base
   self.abstract_class = true
@@ -33,8 +36,6 @@ class SecondAbstractClass < FirstAbstractClass
   self.abstract_class = true
 end
 class Photo < SecondAbstractClass; end
-class Category < ActiveRecord::Base; end
-class Categorization < ActiveRecord::Base; end
 class Smarts < ActiveRecord::Base; end
 class CreditCard < ActiveRecord::Base
   class PinNumber < ActiveRecord::Base
@@ -45,8 +46,6 @@ class CreditCard < ActiveRecord::Base
   class Brand < Category; end
 end
 class MasterCreditCard < ActiveRecord::Base; end
-class Post < ActiveRecord::Base; end
-class Computer < ActiveRecord::Base; end
 class NonExistentTable < ActiveRecord::Base; end
 class TestOracleDefault < ActiveRecord::Base; end
 
@@ -56,12 +55,6 @@ end
 
 class Weird < ActiveRecord::Base; end
 
-class Boolean < ActiveRecord::Base
-  def has_fun
-    super
-  end
-end
-
 class LintTest < ActiveRecord::TestCase
   include ActiveModel::Lint::Tests
 
@@ -73,17 +66,17 @@ class LintTest < ActiveRecord::TestCase
 end
 
 class BasicsTest < ActiveRecord::TestCase
-  fixtures :topics, :companies, :developers, :projects, :computers, :accounts, :minimalistics, 'warehouse-things', :authors, :categorizations, :categories, :posts
+  fixtures :topics, :companies, :developers, :projects, :computers, :accounts, :minimalistics, "warehouse-things", :authors, :author_addresses, :categorizations, :categories, :posts
 
   def test_column_names_are_escaped
     conn      = ActiveRecord::Base.connection
     classname = conn.class.name[/[^:]*$/]
     badchar   = {
-      'SQLite3Adapter'    => '"',
-      'Mysql2Adapter'     => '`',
-      'PostgreSQLAdapter' => '"',
-      'OracleAdapter'     => '"',
-      'FbAdapter'         => '"'
+      "SQLite3Adapter"    => '"',
+      "Mysql2Adapter"     => "`",
+      "PostgreSQLAdapter" => '"',
+      "OracleAdapter"     => '"',
+      "FbAdapter"         => '"'
     }.fetch(classname) {
       raise "need a bad char for #{classname}"
     }
@@ -100,19 +93,25 @@ class BasicsTest < ActiveRecord::TestCase
 
   def test_columns_should_obey_set_primary_key
     pk = Subscriber.columns_hash[Subscriber.primary_key]
-    assert_equal 'nick', pk.name, 'nick should be primary key'
+    assert_equal "nick", pk.name, "nick should be primary key"
   end
 
   def test_primary_key_with_no_id
     assert_nil Edge.primary_key
   end
 
-  unless current_adapter?(:PostgreSQLAdapter, :OracleAdapter, :SQLServerAdapter, :FbAdapter)
-    def test_limit_with_comma
-      assert_deprecated do
-        assert Topic.limit("1,2").to_a
-      end
-    end
+  def test_primary_key_and_references_columns_should_be_identical_type
+    pk = Author.columns_hash["id"]
+    ref = Post.columns_hash["author_id"]
+
+    assert_equal pk.sql_type, ref.sql_type
+  end
+
+  def test_many_mutations
+    car = Car.new name: "<3<3<3"
+    car.engines_count = 0
+    20_000.times { car.engines_count += 1 }
+    assert car.save
   end
 
   def test_limit_without_comma
@@ -137,10 +136,8 @@ class BasicsTest < ActiveRecord::TestCase
   end
 
   def test_limit_should_sanitize_sql_injection_for_limit_with_commas
-    assert_deprecated do
-      assert_raises(ArgumentError) do
-        Topic.limit("1, 7 procedure help()").to_a
-      end
+    assert_raises(ArgumentError) do
+      Topic.limit("1, 7 procedure help()").to_a
     end
   end
 
@@ -164,17 +161,17 @@ class BasicsTest < ActiveRecord::TestCase
 
   def test_previously_changed
     topic = Topic.first
-    topic.title = '<3<3<3'
+    topic.title = "<3<3<3"
     assert_equal({}, topic.previous_changes)
 
     topic.save!
     expected = ["The First Topic", "<3<3<3"]
-    assert_equal(expected, topic.previous_changes['title'])
+    assert_equal(expected, topic.previous_changes["title"])
   end
 
   def test_previously_changed_dup
     topic = Topic.first
-    topic.title = '<3<3<3'
+    topic.title = "<3<3<3"
     topic.save!
 
     t2 = topic.dup
@@ -211,7 +208,7 @@ class BasicsTest < ActiveRecord::TestCase
     with_env_tz eastern_time_zone do
       with_timezone_config default: :utc do
         time = Time.local(2000)
-        topic = Topic.create('written_on' => time)
+        topic = Topic.create("written_on" => time)
         saved_time = Topic.find(topic.id).reload.written_on
         assert_equal time, saved_time
         assert_equal [0, 0, 0, 1, 1, 2000, 6, 1, false, "EST"], time.to_a
@@ -223,9 +220,9 @@ class BasicsTest < ActiveRecord::TestCase
   def test_preserving_time_objects_with_time_with_zone_conversion_to_default_timezone_utc
     with_env_tz eastern_time_zone do
       with_timezone_config default: :utc do
-        Time.use_zone 'Central Time (US & Canada)' do
+        Time.use_zone "Central Time (US & Canada)" do
           time = Time.zone.local(2000)
-          topic = Topic.create('written_on' => time)
+          topic = Topic.create("written_on" => time)
           saved_time = Topic.find(topic.id).reload.written_on
           assert_equal time, saved_time
           assert_equal [0, 0, 0, 1, 1, 2000, 6, 1, false, "CST"], time.to_a
@@ -239,7 +236,7 @@ class BasicsTest < ActiveRecord::TestCase
     with_env_tz eastern_time_zone do
       with_timezone_config default: :local do
         time = Time.utc(2000)
-        topic = Topic.create('written_on' => time)
+        topic = Topic.create("written_on" => time)
         saved_time = Topic.find(topic.id).reload.written_on
         assert_equal time, saved_time
         assert_equal [0, 0, 0, 1, 1, 2000, 6, 1, false, "UTC"], time.to_a
@@ -251,9 +248,9 @@ class BasicsTest < ActiveRecord::TestCase
   def test_preserving_time_objects_with_time_with_zone_conversion_to_default_timezone_local
     with_env_tz eastern_time_zone do
       with_timezone_config default: :local do
-        Time.use_zone 'Central Time (US & Canada)' do
+        Time.use_zone "Central Time (US & Canada)" do
           time = Time.zone.local(2000)
-          topic = Topic.create('written_on' => time)
+          topic = Topic.create("written_on" => time)
           saved_time = Topic.find(topic.id).reload.written_on
           assert_equal time, saved_time
           assert_equal [0, 0, 0, 1, 1, 2000, 6, 1, false, "CST"], time.to_a
@@ -279,49 +276,48 @@ class BasicsTest < ActiveRecord::TestCase
   end
 
   def test_initialize_with_attributes
-    topic = Topic.new({
-      "title" => "initialized from attributes", "written_on" => "2003-12-12 23:23"
-    })
+    topic = Topic.new(
+      "title" => "initialized from attributes", "written_on" => "2003-12-12 23:23")
 
     assert_equal("initialized from attributes", topic.title)
   end
 
   def test_initialize_with_invalid_attribute
-    Topic.new({ "title" => "test",
-      "last_read(1i)" => "2005", "last_read(2i)" => "2", "last_read(3i)" => "31"})
+    Topic.new("title" => "test",
+      "last_read(1i)" => "2005", "last_read(2i)" => "2", "last_read(3i)" => "31")
   rescue ActiveRecord::MultiparameterAssignmentErrors => ex
     assert_equal(1, ex.errors.size)
     assert_equal("last_read", ex.errors[0].attribute)
   end
 
   def test_create_after_initialize_without_block
-    cb = CustomBulb.create(:name => 'Dude')
-    assert_equal('Dude', cb.name)
+    cb = CustomBulb.create(name: "Dude")
+    assert_equal("Dude", cb.name)
     assert_equal(true, cb.frickinawesome)
   end
 
   def test_create_after_initialize_with_block
-    cb = CustomBulb.create {|c| c.name = 'Dude' }
-    assert_equal('Dude', cb.name)
+    cb = CustomBulb.create { |c| c.name = "Dude" }
+    assert_equal("Dude", cb.name)
     assert_equal(true, cb.frickinawesome)
   end
 
   def test_create_after_initialize_with_array_param
-    cbs = CustomBulb.create([{ name: 'Dude' }, { name: 'Bob' }])
-    assert_equal 'Dude', cbs[0].name
-    assert_equal 'Bob', cbs[1].name
+    cbs = CustomBulb.create([{ name: "Dude" }, { name: "Bob" }])
+    assert_equal "Dude", cbs[0].name
+    assert_equal "Bob", cbs[1].name
     assert cbs[0].frickinawesome
     assert !cbs[1].frickinawesome
   end
 
   def test_load
-    topics = Topic.all.merge!(:order => 'id').to_a
+    topics = Topic.all.merge!(order: "id").to_a
     assert_equal(5, topics.size)
     assert_equal(topics(:first).title, topics.first.title)
   end
 
   def test_load_with_condition
-    topics = Topic.all.merge!(:where => "author_name = 'Mary'").to_a
+    topics = Topic.all.merge!(where: "author_name = 'Mary'").to_a
 
     assert_equal(1, topics.size)
     assert_equal(topics(:second).title, topics.first.title)
@@ -443,7 +439,7 @@ class BasicsTest < ActiveRecord::TestCase
 
   if current_adapter?(:Mysql2Adapter)
     def test_update_all_with_order_and_limit
-      assert_equal 1, Topic.limit(1).order('id DESC').update_all(:content => 'bulk updated!')
+      assert_equal 1, Topic.limit(1).order("id DESC").update_all(content: "bulk updated!")
     end
   end
 
@@ -488,12 +484,12 @@ class BasicsTest < ActiveRecord::TestCase
 
     def test_utc_as_time_zone_and_new
       with_timezone_config default: :utc do
-        attributes = { "bonus_time(1i)"=>"2000",
-          "bonus_time(2i)"=>"1",
-          "bonus_time(3i)"=>"1",
-          "bonus_time(4i)"=>"10",
-          "bonus_time(5i)"=>"35",
-          "bonus_time(6i)"=>"50" }
+        attributes = { "bonus_time(1i)" => "2000",
+          "bonus_time(2i)" => "1",
+          "bonus_time(3i)" => "1",
+          "bonus_time(4i)" => "10",
+          "bonus_time(5i)" => "35",
+          "bonus_time(6i)" => "50" }
         topic = Topic.new(attributes)
         assert_equal Time.utc(2000, 1, 1, 10, 35, 50), topic.bonus_time
       end
@@ -518,16 +514,16 @@ class BasicsTest < ActiveRecord::TestCase
   end
 
   def test_find_by_slug
-    assert_equal Topic.find('1-meowmeow'), Topic.find(1)
+    assert_equal Topic.find("1-meowmeow"), Topic.find(1)
   end
 
   def test_find_by_slug_with_array
-    assert_equal Topic.find([1, 2]), Topic.find(['1-meowmeow', '2-hello'])
-    assert_equal 'The Second Topic of the day', Topic.find(['2-hello', '1-meowmeow']).first.title
+    assert_equal Topic.find([1, 2]), Topic.find(["1-meowmeow", "2-hello"])
+    assert_equal "The Second Topic of the day", Topic.find(["2-hello", "1-meowmeow"]).first.title
   end
 
   def test_find_by_slug_with_range
-    assert_equal Topic.where(id: '1-meowmeow'..'2-hello'), Topic.where(id: 1..2)
+    assert_equal Topic.where(id: "1-meowmeow".."2-hello"), Topic.where(id: 1..2)
   end
 
   def test_equality_of_new_records
@@ -536,7 +532,7 @@ class BasicsTest < ActiveRecord::TestCase
   end
 
   def test_equality_of_destroyed_records
-    topic_1 = Topic.new(:title => 'test_1')
+    topic_1 = Topic.new(title: "test_1")
     topic_1.save
     topic_2 = Topic.find(topic_1.id)
     topic_1.destroy
@@ -545,8 +541,8 @@ class BasicsTest < ActiveRecord::TestCase
   end
 
   def test_equality_with_blank_ids
-    one = Subscriber.new(:id => '')
-    two = Subscriber.new(:id => '')
+    one = Subscriber.new(id: "")
+    two = Subscriber.new(id: "")
     assert_equal one, two
   end
 
@@ -555,8 +551,8 @@ class BasicsTest < ActiveRecord::TestCase
     car.bulbs.build
     car.save
 
-    assert car.bulbs == Bulb.where(car_id: car.id), 'CollectionProxy should be comparable with Relation'
-    assert Bulb.where(car_id: car.id) == car.bulbs, 'Relation should be comparable with CollectionProxy'
+    assert car.bulbs == Bulb.where(car_id: car.id), "CollectionProxy should be comparable with Relation"
+    assert Bulb.where(car_id: car.id) == car.bulbs, "Relation should be comparable with CollectionProxy"
   end
 
   def test_equality_of_relation_and_array
@@ -564,7 +560,7 @@ class BasicsTest < ActiveRecord::TestCase
     car.bulbs.build
     car.save
 
-    assert Bulb.where(car_id: car.id) == car.bulbs.to_a, 'Relation should be comparable with Array'
+    assert Bulb.where(car_id: car.id) == car.bulbs.to_a, "Relation should be comparable with Array"
   end
 
   def test_equality_of_relation_and_association_relation
@@ -572,8 +568,8 @@ class BasicsTest < ActiveRecord::TestCase
     car.bulbs.build
     car.save
 
-    assert_equal Bulb.where(car_id: car.id), car.bulbs.includes(:car), 'Relation should be comparable with AssociationRelation'
-    assert_equal car.bulbs.includes(:car), Bulb.where(car_id: car.id), 'AssociationRelation should be comparable with Relation'
+    assert_equal Bulb.where(car_id: car.id), car.bulbs.includes(:car), "Relation should be comparable with AssociationRelation"
+    assert_equal car.bulbs.includes(:car), Bulb.where(car_id: car.id), "AssociationRelation should be comparable with Relation"
   end
 
   def test_equality_of_collection_proxy_and_association_relation
@@ -581,8 +577,8 @@ class BasicsTest < ActiveRecord::TestCase
     car.bulbs.build
     car.save
 
-    assert_equal car.bulbs, car.bulbs.includes(:car), 'CollectionProxy should be comparable with AssociationRelation'
-    assert_equal car.bulbs.includes(:car), car.bulbs, 'AssociationRelation should be comparable with CollectionProxy'
+    assert_equal car.bulbs, car.bulbs.includes(:car), "CollectionProxy should be comparable with AssociationRelation"
+    assert_equal car.bulbs.includes(:car), car.bulbs, "AssociationRelation should be comparable with CollectionProxy"
   end
 
   def test_hashing
@@ -604,24 +600,24 @@ class BasicsTest < ActiveRecord::TestCase
 
   def test_create_without_prepared_statement
     topic = Topic.connection.unprepared_statement do
-      Topic.create(:title => 'foo')
+      Topic.create(title: "foo")
     end
 
     assert_equal topic, Topic.find(topic.id)
   end
 
   def test_destroy_without_prepared_statement
-    topic = Topic.create(title: 'foo')
+    topic = Topic.create(title: "foo")
     Topic.connection.unprepared_statement do
       Topic.find(topic.id).destroy
     end
 
-    assert_equal nil, Topic.find_by_id(topic.id)
+    assert_nil Topic.find_by_id(topic.id)
   end
 
   def test_comparison_with_different_objects
     topic = Topic.create
-    category = Category.create(:name => "comparison")
+    category = Category.create(name: "comparison")
     assert_nil topic <=> category
   end
 
@@ -633,9 +629,9 @@ class BasicsTest < ActiveRecord::TestCase
   end
 
   def test_readonly_attributes
-    assert_equal Set.new([ 'title' , 'comments_count' ]), ReadonlyTitlePost.readonly_attributes
+    assert_equal Set.new([ "title", "comments_count" ]), ReadonlyTitlePost.readonly_attributes
 
-    post = ReadonlyTitlePost.create(:title => "cannot change this", :body => "changeable")
+    post = ReadonlyTitlePost.create(title: "cannot change this", body: "changeable")
     post.reload
     assert_equal "cannot change this", post.title
 
@@ -647,8 +643,8 @@ class BasicsTest < ActiveRecord::TestCase
 
   def test_unicode_column_name
     Weird.reset_column_information
-    weird = Weird.create(:なまえ => 'たこ焼き仮面')
-    assert_equal 'たこ焼き仮面', weird.なまえ
+    weird = Weird.create(なまえ: "たこ焼き仮面")
+    assert_equal "たこ焼き仮面", weird.なまえ
   end
 
   unless current_adapter?(:PostgreSQLAdapter)
@@ -658,7 +654,7 @@ class BasicsTest < ActiveRecord::TestCase
 
       Weird.reset_column_information
 
-      assert_equal ["EUC-JP"], Weird.columns.map {|c| c.name.encoding.name }.uniq
+      assert_equal ["EUC-JP"], Weird.columns.map { |c| c.name.encoding.name }.uniq
     ensure
       silence_warnings { Encoding.default_internal = old_default_internal }
       Weird.reset_column_information
@@ -666,21 +662,21 @@ class BasicsTest < ActiveRecord::TestCase
   end
 
   def test_non_valid_identifier_column_name
-    weird = Weird.create('a$b' => 'value')
+    weird = Weird.create("a$b" => "value")
     weird.reload
-    assert_equal 'value', weird.send('a$b')
-    assert_equal 'value', weird.read_attribute('a$b')
+    assert_equal "value", weird.send("a$b")
+    assert_equal "value", weird.read_attribute("a$b")
 
-    weird.update_columns('a$b' => 'value2')
+    weird.update_columns("a$b" => "value2")
     weird.reload
-    assert_equal 'value2', weird.send('a$b')
-    assert_equal 'value2', weird.read_attribute('a$b')
+    assert_equal "value2", weird.send("a$b")
+    assert_equal "value2", weird.read_attribute("a$b")
   end
 
   def test_group_weirds_by_from
-    Weird.create('a$b' => 'value', :from => 'aaron')
+    Weird.create("a$b" => "value", :from => "aaron")
     count = Weird.group(Weird.arel_table[:from]).count
-    assert_equal 1, count['aaron']
+    assert_equal 1, count["aaron"]
   end
 
   def test_attributes_on_dummy_time
@@ -709,12 +705,23 @@ class BasicsTest < ActiveRecord::TestCase
     assert_nil topic.bonus_time
   end
 
+  def test_attributes
+    category = Category.new(name: "Ruby")
+
+    expected_attributes = category.attribute_names.map do |attribute_name|
+      [attribute_name, category.public_send(attribute_name)]
+    end.to_h
+
+    assert_instance_of Hash, category.attributes
+    assert_equal expected_attributes, category.attributes
+  end
+
   def test_boolean
-    b_nil = Boolean.create({ "value" => nil })
+    b_nil = Boolean.create("value" => nil)
     nil_id = b_nil.id
-    b_false = Boolean.create({ "value" => false })
+    b_false = Boolean.create("value" => false)
     false_id = b_false.id
-    b_true = Boolean.create({ "value" => true })
+    b_true = Boolean.create("value" => true)
     true_id = b_true.id
 
     b_nil = Boolean.find(nil_id)
@@ -726,7 +733,7 @@ class BasicsTest < ActiveRecord::TestCase
   end
 
   def test_boolean_without_questionmark
-    b_true = Boolean.create({ "value" => true })
+    b_true = Boolean.create("value" => true)
     true_id = b_true.id
 
     subclass   = Class.new(Boolean).find true_id
@@ -736,11 +743,11 @@ class BasicsTest < ActiveRecord::TestCase
   end
 
   def test_boolean_cast_from_string
-    b_blank = Boolean.create({ "value" => "" })
+    b_blank = Boolean.create("value" => "")
     blank_id = b_blank.id
-    b_false = Boolean.create({ "value" => "0" })
+    b_false = Boolean.create("value" => "0")
     false_id = b_false.id
-    b_true = Boolean.create({ "value" => "1" })
+    b_true = Boolean.create("value" => "1")
     true_id = b_true.id
 
     b_blank = Boolean.find(blank_id)
@@ -789,8 +796,8 @@ class BasicsTest < ActiveRecord::TestCase
   DeveloperSalary = Struct.new(:amount)
   def test_dup_with_aggregate_of_same_name_as_attribute
     developer_with_aggregate = Class.new(ActiveRecord::Base) do
-      self.table_name = 'developers'
-      composed_of :salary, :class_name => 'BasicsTest::DeveloperSalary', :mapping => [%w(salary amount)]
+      self.table_name = "developers"
+      composed_of :salary, class_name: "BasicsTest::DeveloperSalary", mapping: [%w(salary amount)]
     end
 
     dev = developer_with_aggregate.find(1)
@@ -837,7 +844,7 @@ class BasicsTest < ActiveRecord::TestCase
   end
 
   def test_clone_of_new_object_marks_attributes_as_dirty
-    developer = Developer.new :name => 'Bjorn', :salary => 100000
+    developer = Developer.new name: "Bjorn", salary: 100000
     assert developer.name_changed?
     assert developer.salary_changed?
 
@@ -847,7 +854,7 @@ class BasicsTest < ActiveRecord::TestCase
   end
 
   def test_clone_of_new_object_marks_as_dirty_only_changed_attributes
-    developer = Developer.new :name => 'Bjorn'
+    developer = Developer.new name: "Bjorn"
     assert developer.name_changed?            # obviously
     assert !developer.salary_changed?         # attribute has non-nil default value, so treated as not changed
 
@@ -857,7 +864,7 @@ class BasicsTest < ActiveRecord::TestCase
   end
 
   def test_dup_of_saved_object_marks_attributes_as_dirty
-    developer = Developer.create! :name => 'Bjorn', :salary => 100000
+    developer = Developer.create! name: "Bjorn", salary: 100000
     assert !developer.name_changed?
     assert !developer.salary_changed?
 
@@ -867,7 +874,7 @@ class BasicsTest < ActiveRecord::TestCase
   end
 
   def test_dup_of_saved_object_marks_as_dirty_only_changed_attributes
-    developer = Developer.create! :name => 'Bjorn'
+    developer = Developer.create! name: "Bjorn"
     assert !developer.name_changed?           # both attributes of saved object should be treated as not changed
     assert !developer.salary_changed?
 
@@ -878,10 +885,15 @@ class BasicsTest < ActiveRecord::TestCase
 
   def test_bignum
     company = Company.find(1)
-    company.rating = 2147483647
+    company.rating = 2147483648
     company.save
     company = Company.find(1)
-    assert_equal 2147483647, company.rating
+    assert_equal 2147483648, company.rating
+  end
+
+  def test_bignum_pk
+    company = Company.create!(id: 2147483648, name: "foo")
+    assert_equal company, Company.find(company.id)
   end
 
   # TODO: extend defaults tests to other databases!
@@ -892,90 +904,16 @@ class BasicsTest < ActiveRecord::TestCase
 
         # fixed dates / times
         assert_equal Date.new(2004, 1, 1), default.fixed_date
-        assert_equal Time.local(2004, 1,1,0,0,0,0), default.fixed_time
+        assert_equal Time.local(2004, 1, 1, 0, 0, 0, 0), default.fixed_time
 
         # char types
-        assert_equal 'Y', default.char1
-        assert_equal 'a varchar field', default.char2
-        assert_equal 'a text field', default.char3
+        assert_equal "Y", default.char1
+        assert_equal "a varchar field", default.char2
+        assert_equal "a text field", default.char3
       end
     end
   end
 
-  class NumericData < ActiveRecord::Base
-    self.table_name = 'numeric_data'
-
-    attribute :my_house_population, :integer
-    attribute :atoms_in_universe, :integer
-  end
-
-  def test_big_decimal_conditions
-    m = NumericData.new(
-      :bank_balance => 1586.43,
-      :big_bank_balance => BigDecimal("1000234000567.95"),
-      :world_population => 6000000000,
-      :my_house_population => 3
-    )
-    assert m.save
-    assert_equal 0, NumericData.where("bank_balance > ?", 2000.0).count
-  end
-
-  def test_numeric_fields
-    m = NumericData.new(
-      :bank_balance => 1586.43,
-      :big_bank_balance => BigDecimal("1000234000567.95"),
-      :world_population => 6000000000,
-      :my_house_population => 3
-    )
-    assert m.save
-
-    m1 = NumericData.find(m.id)
-    assert_not_nil m1
-
-    # As with migration_test.rb, we should make world_population >= 2**62
-    # to cover 64-bit platforms and test it is a Bignum, but the main thing
-    # is that it's an Integer.
-    assert_kind_of Integer, m1.world_population
-    assert_equal 6000000000, m1.world_population
-
-    assert_kind_of Integer, m1.my_house_population
-    assert_equal 3, m1.my_house_population
-
-    assert_kind_of BigDecimal, m1.bank_balance
-    assert_equal BigDecimal("1586.43"), m1.bank_balance
-
-    assert_kind_of BigDecimal, m1.big_bank_balance
-    assert_equal BigDecimal("1000234000567.95"), m1.big_bank_balance
-  end
-
-  def test_numeric_fields_with_scale
-    m = NumericData.new(
-      :bank_balance => 1586.43122334,
-      :big_bank_balance => BigDecimal("234000567.952344"),
-      :world_population => 6000000000,
-      :my_house_population => 3
-    )
-    assert m.save
-
-    m1 = NumericData.find(m.id)
-    assert_not_nil m1
-
-    # As with migration_test.rb, we should make world_population >= 2**62
-    # to cover 64-bit platforms and test it is a Bignum, but the main thing
-    # is that it's an Integer.
-    assert_kind_of Integer, m1.world_population
-    assert_equal 6000000000, m1.world_population
-
-    assert_kind_of Integer, m1.my_house_population
-    assert_equal 3, m1.my_house_population
-
-    assert_kind_of BigDecimal, m1.bank_balance
-    assert_equal BigDecimal("1586.43"), m1.bank_balance
-
-    assert_kind_of BigDecimal, m1.big_bank_balance
-    assert_equal BigDecimal("234000567.95"), m1.big_bank_balance
-  end
-
   def test_auto_id
     auto = AutoId.new
     auto.save
@@ -999,16 +937,16 @@ class BasicsTest < ActiveRecord::TestCase
   end
 
   def test_quoting_arrays
-    replies = Reply.all.merge!(:where => [ "id IN (?)", topics(:first).replies.collect(&:id) ]).to_a
+    replies = Reply.all.merge!(where: [ "id IN (?)", topics(:first).replies.collect(&:id) ]).to_a
     assert_equal topics(:first).replies.size, replies.size
 
-    replies = Reply.all.merge!(:where => [ "id IN (?)", [] ]).to_a
+    replies = Reply.all.merge!(where: [ "id IN (?)", [] ]).to_a
     assert_equal 0, replies.size
   end
 
   def test_quote
     author_name = "\\ \001 ' \n \\n \""
-    topic = Topic.create('author_name' => author_name)
+    topic = Topic.create("author_name" => author_name)
     assert_equal author_name, Topic.find(topic.id).author_name
   end
 
@@ -1032,12 +970,6 @@ class BasicsTest < ActiveRecord::TestCase
     assert_equal t1.title, t2.title
   end
 
-  def test_reload_with_exclusive_scope
-    dev = DeveloperCalledDavid.first
-    dev.update!(name: "NotDavid" )
-    assert_equal dev, dev.reload
-  end
-
   def test_switching_between_table_name
     k = Class.new(Joke)
 
@@ -1093,7 +1025,7 @@ class BasicsTest < ActiveRecord::TestCase
   def test_set_table_name_symbol_converted_to_string
     k = Class.new(Joke)
     k.table_name = :cold_jokes
-    assert_equal 'cold_jokes', k.table_name
+    assert_equal "cold_jokes", k.table_name
   end
 
   def test_quoted_table_name_after_set_table_name
@@ -1109,7 +1041,7 @@ class BasicsTest < ActiveRecord::TestCase
   end
 
   def test_set_table_name_with_inheritance
-    k = Class.new( ActiveRecord::Base )
+    k = Class.new(ActiveRecord::Base)
     def k.name; "Foo"; end
     def k.table_name; super + "ks"; end
     assert_equal "foosks", k.table_name
@@ -1127,45 +1059,31 @@ class BasicsTest < ActiveRecord::TestCase
 
   def test_count_with_join
     res = Post.count_by_sql "SELECT COUNT(*) FROM posts LEFT JOIN comments ON posts.id=comments.post_id WHERE posts.#{QUOTED_TYPE} = 'Post'"
-
     res2 = Post.where("posts.#{QUOTED_TYPE} = 'Post'").joins("LEFT JOIN comments ON posts.id=comments.post_id").count
     assert_equal res, res2
 
-    res3 = nil
-    assert_nothing_raised do
-      res3 = Post.where("posts.#{QUOTED_TYPE} = 'Post'").joins("LEFT JOIN comments ON posts.id=comments.post_id").count
-    end
-    assert_equal res, res3
-
     res4 = Post.count_by_sql "SELECT COUNT(p.id) FROM posts p, comments co WHERE p.#{QUOTED_TYPE} = 'Post' AND p.id=co.post_id"
-    res5 = nil
-    assert_nothing_raised do
-      res5 = Post.where("p.#{QUOTED_TYPE} = 'Post' AND p.id=co.post_id").joins("p, comments co").select("p.id").count
-    end
-
+    res5 = Post.where("p.#{QUOTED_TYPE} = 'Post' AND p.id=co.post_id").joins("p, comments co").select("p.id").count
     assert_equal res4, res5
 
     res6 = Post.count_by_sql "SELECT COUNT(DISTINCT p.id) FROM posts p, comments co WHERE p.#{QUOTED_TYPE} = 'Post' AND p.id=co.post_id"
-    res7 = nil
-    assert_nothing_raised do
-      res7 = Post.where("p.#{QUOTED_TYPE} = 'Post' AND p.id=co.post_id").joins("p, comments co").select("p.id").distinct.count
-    end
+    res7 = Post.where("p.#{QUOTED_TYPE} = 'Post' AND p.id=co.post_id").joins("p, comments co").select("p.id").distinct.count
     assert_equal res6, res7
   end
 
   def test_no_limit_offset
     assert_nothing_raised do
-      Developer.all.merge!(:offset => 2).to_a
+      Developer.all.merge!(offset: 2).to_a
     end
   end
 
   def test_find_last
-    last  = Developer.last
-    assert_equal last, Developer.all.merge!(:order => 'id desc').first
+    last = Developer.last
+    assert_equal last, Developer.all.merge!(order: "id desc").first
   end
 
   def test_last
-    assert_equal Developer.all.merge!(:order => 'id desc').first, Developer.last
+    assert_equal Developer.all.merge!(order: "id desc").first, Developer.last
   end
 
   def test_all
@@ -1175,37 +1093,37 @@ class BasicsTest < ActiveRecord::TestCase
   end
 
   def test_all_with_conditions
-    assert_equal Developer.all.merge!(:order => 'id desc').to_a, Developer.order('id desc').to_a
+    assert_equal Developer.all.merge!(order: "id desc").to_a, Developer.order("id desc").to_a
   end
 
   def test_find_ordered_last
-    last  = Developer.all.merge!(:order => 'developers.salary ASC').last
-    assert_equal last, Developer.all.merge!(:order => 'developers.salary ASC').to_a.last
+    last = Developer.all.merge!(order: "developers.salary ASC").last
+    assert_equal last, Developer.all.merge!(order: "developers.salary ASC").to_a.last
   end
 
   def test_find_reverse_ordered_last
-    last  = Developer.all.merge!(:order => 'developers.salary DESC').last
-    assert_equal last, Developer.all.merge!(:order => 'developers.salary DESC').to_a.last
+    last = Developer.all.merge!(order: "developers.salary DESC").last
+    assert_equal last, Developer.all.merge!(order: "developers.salary DESC").to_a.last
   end
 
   def test_find_multiple_ordered_last
-    last  = Developer.all.merge!(:order => 'developers.name, developers.salary DESC').last
-    assert_equal last, Developer.all.merge!(:order => 'developers.name, developers.salary DESC').to_a.last
+    last = Developer.all.merge!(order: "developers.name, developers.salary DESC").last
+    assert_equal last, Developer.all.merge!(order: "developers.name, developers.salary DESC").to_a.last
   end
 
   def test_find_keeps_multiple_order_values
-    combined = Developer.all.merge!(:order => 'developers.name, developers.salary').to_a
-    assert_equal combined, Developer.all.merge!(:order => ['developers.name', 'developers.salary']).to_a
+    combined = Developer.all.merge!(order: "developers.name, developers.salary").to_a
+    assert_equal combined, Developer.all.merge!(order: ["developers.name", "developers.salary"]).to_a
   end
 
   def test_find_keeps_multiple_group_values
-    combined = Developer.all.merge!(:group => 'developers.name, developers.salary, developers.id, developers.created_at, developers.updated_at, developers.created_on, developers.updated_on').to_a
-    assert_equal combined, Developer.all.merge!(:group => ['developers.name', 'developers.salary', 'developers.id', 'developers.created_at', 'developers.updated_at', 'developers.created_on', 'developers.updated_on']).to_a
+    combined = Developer.all.merge!(group: "developers.name, developers.salary, developers.id, developers.created_at, developers.updated_at, developers.created_on, developers.updated_on").to_a
+    assert_equal combined, Developer.all.merge!(group: ["developers.name", "developers.salary", "developers.id", "developers.created_at", "developers.updated_at", "developers.created_on", "developers.updated_on"]).to_a
   end
 
   def test_find_symbol_ordered_last
-    last  = Developer.all.merge!(:order => :salary).last
-    assert_equal last, Developer.all.merge!(:order => :salary).to_a.last
+    last = Developer.all.merge!(order: :salary).last
+    assert_equal last, Developer.all.merge!(order: :salary).to_a.last
   end
 
   def test_abstract_class_table_name
@@ -1216,7 +1134,7 @@ class BasicsTest < ActiveRecord::TestCase
     old_class = LooseDescendant
     Object.send :remove_const, :LooseDescendant
 
-    descendant = old_class.create! :first_name => 'bob'
+    descendant = old_class.create! first_name: "bob"
     assert_not_nil LoosePerson.find(descendant.id), "Should have found instance of LooseDescendant when finding abstract LoosePerson: #{descendant.inspect}"
   ensure
     unless Object.const_defined?(:LooseDescendant)
@@ -1225,7 +1143,7 @@ class BasicsTest < ActiveRecord::TestCase
   end
 
   def test_assert_queries
-    query = lambda { ActiveRecord::Base.connection.execute 'select count(*) from developers' }
+    query = lambda { ActiveRecord::Base.connection.execute "select count(*) from developers" }
     assert_queries(2) { 2.times { query.call } }
     assert_queries 1, &query
     assert_no_queries { assert true }
@@ -1236,9 +1154,9 @@ class BasicsTest < ActiveRecord::TestCase
     log = StringIO.new
     ActiveRecord::Base.logger = ActiveSupport::Logger.new(log)
     ActiveRecord::Base.logger.level = Logger::WARN
-    ActiveRecord::Base.benchmark("Debug Topic Count", :level => :debug) { Topic.count }
-    ActiveRecord::Base.benchmark("Warn Topic Count",  :level => :warn)  { Topic.count }
-    ActiveRecord::Base.benchmark("Error Topic Count", :level => :error) { Topic.count }
+    ActiveRecord::Base.benchmark("Debug Topic Count", level: :debug) { Topic.count }
+    ActiveRecord::Base.benchmark("Warn Topic Count",  level: :warn)  { Topic.count }
+    ActiveRecord::Base.benchmark("Error Topic Count", level: :error) { Topic.count }
     assert_no_match(/Debug Topic Count/, log.string)
     assert_match(/Warn Topic Count/, log.string)
     assert_match(/Error Topic Count/, log.string)
@@ -1251,7 +1169,7 @@ class BasicsTest < ActiveRecord::TestCase
     log = StringIO.new
     ActiveRecord::Base.logger = ActiveSupport::Logger.new(log)
     ActiveRecord::Base.logger.level = Logger::DEBUG
-    ActiveRecord::Base.benchmark("Logging", :level => :debug, :silence => false)  { ActiveRecord::Base.logger.debug "Quiet" }
+    ActiveRecord::Base.benchmark("Logging", level: :debug, silence: false)  { ActiveRecord::Base.logger.debug "Quiet" }
     assert_match(/Quiet/, log.string)
   ensure
     ActiveRecord::Base.logger = original_logger
@@ -1259,9 +1177,9 @@ class BasicsTest < ActiveRecord::TestCase
 
   def test_clear_cache!
     # preheat cache
-    c1 = Post.connection.schema_cache.columns('posts')
+    c1 = Post.connection.schema_cache.columns("posts")
     ActiveRecord::Base.clear_cache!
-    c2 = Post.connection.schema_cache.columns('posts')
+    c2 = Post.connection.schema_cache.columns("posts")
     c1.each_with_index do |v, i|
       assert_not_same v, c2[i]
     end
@@ -1278,13 +1196,13 @@ class BasicsTest < ActiveRecord::TestCase
     ActiveSupport::Dependencies.remove_unloadable_constants!
     assert_nil ActiveRecord::Scoping::ScopeRegistry.value_for(:current_scope, klass)
   ensure
-    Object.class_eval{ remove_const :UnloadablePost } if defined?(UnloadablePost)
+    Object.class_eval { remove_const :UnloadablePost } if defined?(UnloadablePost)
   end
 
   def test_marshal_round_trip
     expected = posts(:welcome)
     marshalled = Marshal.dump(expected)
-    actual   = Marshal.load(marshalled)
+    actual = Marshal.load(marshalled)
 
     assert_equal expected.attributes, actual.attributes
   end
@@ -1352,11 +1270,11 @@ class BasicsTest < ActiveRecord::TestCase
   end
 
   def test_has_attribute
-    assert Company.has_attribute?('id')
-    assert Company.has_attribute?('type')
-    assert Company.has_attribute?('name')
-    assert_not Company.has_attribute?('lastname')
-    assert_not Company.has_attribute?('age')
+    assert Company.has_attribute?("id")
+    assert Company.has_attribute?("type")
+    assert Company.has_attribute?("name")
+    assert_not Company.has_attribute?("lastname")
+    assert_not Company.has_attribute?("age")
   end
 
   def test_has_attribute_with_symbol
@@ -1373,18 +1291,12 @@ class BasicsTest < ActiveRecord::TestCase
   end
 
   def test_touch_should_raise_error_on_a_new_object
-    company = Company.new(:rating => 1, :name => "37signals", :firm_name => "37signals")
+    company = Company.new(rating: 1, name: "37signals", firm_name: "37signals")
     assert_raises(ActiveRecord::ActiveRecordError) do
       company.touch :updated_at
     end
   end
 
-  def test_uniq_delegates_to_scoped
-    assert_deprecated do
-      assert_equal Bird.all.distinct, Bird.uniq
-    end
-  end
-
   def test_distinct_delegates_to_scoped
     assert_equal Bird.all.distinct, Bird.distinct
   end
@@ -1395,37 +1307,47 @@ class BasicsTest < ActiveRecord::TestCase
 
   def test_column_types_typecast
     topic = Topic.first
-    assert_not_equal 't.lo', topic.author_name
+    assert_not_equal "t.lo", topic.author_name
 
     attrs = topic.attributes.dup
-    attrs.delete 'id'
+    attrs.delete "id"
 
     typecast = Class.new(ActiveRecord::Type::Value) {
-      def cast value
+      def cast(value)
         "t.lo"
       end
     }
 
-    types = { 'author_name' => typecast.new }
+    types = { "author_name" => typecast.new }
     topic = Topic.instantiate(attrs, types)
 
-    assert_equal 't.lo', topic.author_name
+    assert_equal "t.lo", topic.author_name
   end
 
   def test_typecasting_aliases
-    assert_equal 10, Topic.select('10 as tenderlove').first.tenderlove
+    assert_equal 10, Topic.select("10 as tenderlove").first.tenderlove
   end
 
   def test_slice
-    company = Company.new(:rating => 1, :name => "37signals", :firm_name => "37signals")
+    company = Company.new(rating: 1, name: "37signals", firm_name: "37signals")
     hash = company.slice(:name, :rating, "arbitrary_method")
     assert_equal hash[:name], company.name
-    assert_equal hash['name'], company.name
+    assert_equal hash["name"], company.name
     assert_equal hash[:rating], company.rating
-    assert_equal hash['arbitrary_method'], company.arbitrary_method
+    assert_equal hash["arbitrary_method"], company.arbitrary_method
     assert_equal hash[:arbitrary_method], company.arbitrary_method
     assert_nil hash[:firm_name]
-    assert_nil hash['firm_name']
+    assert_nil hash["firm_name"]
+  end
+
+  def test_slice_accepts_array_argument
+    attrs = {
+      title: "slice",
+      author_name: "@Cohen-Carlisle",
+      content: "accept arrays so I don't have to splat"
+    }.with_indifferent_access
+    topic = Topic.new(attrs)
+    assert_equal attrs, topic.slice(attrs.keys)
   end
 
   def test_default_values_are_deeply_dupped
@@ -1436,7 +1358,7 @@ class BasicsTest < ActiveRecord::TestCase
 
   test "scoped can take a values hash" do
     klass = Class.new(ActiveRecord::Base)
-    assert_equal ['foo'], klass.all.merge!(select: 'foo').select_values
+    assert_equal ["foo"], klass.all.merge!(select: "foo").select_values
   end
 
   test "connection_handler can be overridden" do
@@ -1518,19 +1440,83 @@ class BasicsTest < ActiveRecord::TestCase
 
   test "ignored columns are not present in columns_hash" do
     cache_columns = Developer.connection.schema_cache.columns_hash(Developer.table_name)
-    assert_includes cache_columns.keys, 'first_name'
-    refute_includes Developer.columns_hash.keys, 'first_name'
+    assert_includes cache_columns.keys, "first_name"
+    assert_not_includes Developer.columns_hash.keys, "first_name"
+    assert_not_includes SubDeveloper.columns_hash.keys, "first_name"
+    assert_not_includes SymbolIgnoredDeveloper.columns_hash.keys, "first_name"
   end
 
   test "ignored columns have no attribute methods" do
     refute Developer.new.respond_to?(:first_name)
     refute Developer.new.respond_to?(:first_name=)
     refute Developer.new.respond_to?(:first_name?)
+    refute SubDeveloper.new.respond_to?(:first_name)
+    refute SubDeveloper.new.respond_to?(:first_name=)
+    refute SubDeveloper.new.respond_to?(:first_name?)
+    refute SymbolIgnoredDeveloper.new.respond_to?(:first_name)
+    refute SymbolIgnoredDeveloper.new.respond_to?(:first_name=)
+    refute SymbolIgnoredDeveloper.new.respond_to?(:first_name?)
   end
 
   test "ignored columns don't prevent explicit declaration of attribute methods" do
     assert Developer.new.respond_to?(:last_name)
     assert Developer.new.respond_to?(:last_name=)
     assert Developer.new.respond_to?(:last_name?)
+    assert SubDeveloper.new.respond_to?(:last_name)
+    assert SubDeveloper.new.respond_to?(:last_name=)
+    assert SubDeveloper.new.respond_to?(:last_name?)
+    assert SymbolIgnoredDeveloper.new.respond_to?(:last_name)
+    assert SymbolIgnoredDeveloper.new.respond_to?(:last_name=)
+    assert SymbolIgnoredDeveloper.new.respond_to?(:last_name?)
+  end
+
+  test "ignored columns are stored as an array of string" do
+    assert_equal(%w(first_name last_name), Developer.ignored_columns)
+    assert_equal(%w(first_name last_name), SymbolIgnoredDeveloper.ignored_columns)
+  end
+
+  test "when #reload called, ignored columns' attribute methods are not defined" do
+    developer = Developer.create!(name: "Developer")
+    refute developer.respond_to?(:first_name)
+    refute developer.respond_to?(:first_name=)
+
+    developer.reload
+
+    refute developer.respond_to?(:first_name)
+    refute developer.respond_to?(:first_name=)
+  end
+
+  test "ignored columns not included in SELECT" do
+    query = Developer.all.to_sql.downcase
+
+    # ignored column
+    refute query.include?("first_name")
+
+    # regular column
+    assert query.include?("name")
+  end
+
+  test "column names are quoted when using #from clause and model has ignored columns" do
+    refute_empty Developer.ignored_columns
+    query = Developer.from("developers").to_sql
+    quoted_id = "#{Developer.quoted_table_name}.#{Developer.quoted_primary_key}"
+
+    assert_match(/SELECT #{quoted_id}.* FROM developers/, query)
+  end
+
+  test "using table name qualified column names unless having SELECT list explicitly" do
+    assert_equal developers(:david), Developer.from("developers").joins(:shared_computers).take
+  end
+
+  test "protected environments by default is an array with production" do
+    assert_equal ["production"], ActiveRecord::Base.protected_environments
+  end
+
+  def test_protected_environments_are_stored_as_an_array_of_string
+    previous_protected_environments = ActiveRecord::Base.protected_environments
+    ActiveRecord::Base.protected_environments = [:staging, "production"]
+    assert_equal ["staging", "production"], ActiveRecord::Base.protected_environments
+  ensure
+    ActiveRecord::Base.protected_environments = previous_protected_environments
   end
 end
diff --git a/activerecord/test/cases/batches_test.rb b/activerecord/test/cases/batches_test.rb
index db71840658..be8aeed5ac 100644
--- a/activerecord/test/cases/batches_test.rb
+++ b/activerecord/test/cases/batches_test.rb
@@ -1,6 +1,9 @@
-require 'cases/helper'
-require 'models/post'
-require 'models/subscriber'
+# frozen_string_literal: true
+
+require "cases/helper"
+require "models/comment"
+require "models/post"
+require "models/subscriber"
 
 class EachTest < ActiveRecord::TestCase
   fixtures :posts, :subscribers
@@ -8,12 +11,12 @@ class EachTest < ActiveRecord::TestCase
   def setup
     @posts = Post.order("id asc")
     @total = Post.count
-    Post.count('id') # preheat arel's table cache
+    Post.count("id") # preheat arel's table cache
   end
 
   def test_each_should_execute_one_query_per_batch
     assert_queries(@total + 1) do
-      Post.find_each(:batch_size => 1) do |post|
+      Post.find_each(batch_size: 1) do |post|
         assert_kind_of Post, post
       end
     end
@@ -21,31 +24,29 @@ class EachTest < ActiveRecord::TestCase
 
   def test_each_should_not_return_query_chain_and_execute_only_one_query
     assert_queries(1) do
-      result = Post.find_each(:batch_size => 100000){ }
+      result = Post.find_each(batch_size: 100000) {}
       assert_nil result
     end
   end
 
   def test_each_should_return_an_enumerator_if_no_block_is_present
     assert_queries(1) do
-      Post.find_each(:batch_size => 100000).with_index do |post, index|
+      Post.find_each(batch_size: 100000).with_index do |post, index|
         assert_kind_of Post, post
         assert_kind_of Integer, index
       end
     end
   end
 
-  if Enumerator.method_defined? :size
-    def test_each_should_return_a_sized_enumerator
-      assert_equal 11, Post.find_each(batch_size: 1).size
-      assert_equal 5, Post.find_each(batch_size:  2, start: 7).size
-      assert_equal 11, Post.find_each(batch_size: 10_000).size
-    end
+  def test_each_should_return_a_sized_enumerator
+    assert_equal 11, Post.find_each(batch_size: 1).size
+    assert_equal 5, Post.find_each(batch_size:  2, start: 7).size
+    assert_equal 11, Post.find_each(batch_size: 10_000).size
   end
 
   def test_each_enumerator_should_execute_one_query_per_batch
     assert_queries(@total + 1) do
-      Post.find_each(:batch_size => 1).with_index do |post, index|
+      Post.find_each(batch_size: 1).with_index do |post, index|
         assert_kind_of Post, post
         assert_kind_of Integer, index
       end
@@ -62,16 +63,32 @@ class EachTest < ActiveRecord::TestCase
 
   def test_each_should_execute_if_id_is_in_select
     assert_queries(6) do
-      Post.select("id, title, type").find_each(:batch_size => 2) do |post|
+      Post.select("id, title, type").find_each(batch_size: 2) do |post|
         assert_kind_of Post, post
       end
     end
   end
 
-  def test_warn_if_limit_scope_is_set
-    assert_called(ActiveRecord::Base.logger, :warn) do
-      Post.limit(1).find_each { |post| post }
+  test "find_each should honor limit if passed a block" do
+    limit = @total - 1
+    total = 0
+
+    Post.limit(limit).find_each do |post|
+      total += 1
+    end
+
+    assert_equal limit, total
+  end
+
+  test "find_each should honor limit if no block is passed" do
+    limit = @total - 1
+    total = 0
+
+    Post.limit(limit).find_each.each do |post|
+      total += 1
     end
+
+    assert_equal limit, total
   end
 
   def test_warn_if_order_scope_is_set
@@ -84,7 +101,7 @@ class EachTest < ActiveRecord::TestCase
     previous_logger = ActiveRecord::Base.logger
     ActiveRecord::Base.logger = nil
     assert_nothing_raised do
-      Post.limit(1).find_each { |post| post }
+      Post.order("comments_count DESC").find_each { |post| post }
     end
   ensure
     ActiveRecord::Base.logger = previous_logger
@@ -92,7 +109,7 @@ class EachTest < ActiveRecord::TestCase
 
   def test_find_in_batches_should_return_batches
     assert_queries(@total + 1) do
-      Post.find_in_batches(:batch_size => 1) do |batch|
+      Post.find_in_batches(batch_size: 1) do |batch|
         assert_kind_of Array, batch
         assert_kind_of Post, batch.first
       end
@@ -119,18 +136,18 @@ class EachTest < ActiveRecord::TestCase
 
   def test_find_in_batches_shouldnt_execute_query_unless_needed
     assert_queries(2) do
-      Post.find_in_batches(:batch_size => @total) {|batch| assert_kind_of Array, batch }
+      Post.find_in_batches(batch_size: @total) { |batch| assert_kind_of Array, batch }
     end
 
     assert_queries(1) do
-      Post.find_in_batches(:batch_size => @total + 1) {|batch| assert_kind_of Array, batch }
+      Post.find_in_batches(batch_size: @total + 1) { |batch| assert_kind_of Array, batch }
     end
   end
 
   def test_find_in_batches_should_quote_batch_order
     c = Post.connection
-    assert_sql(/ORDER BY #{c.quote_table_name('posts')}.#{c.quote_column_name('id')}/) do
-      Post.find_in_batches(:batch_size => 1) do |batch|
+    assert_sql(/ORDER BY #{c.quote_table_name('posts')}\.#{c.quote_column_name('id')}/) do
+      Post.find_in_batches(batch_size: 1) do |batch|
         assert_kind_of Array, batch
         assert_kind_of Post, batch.first
       end
@@ -138,11 +155,11 @@ class EachTest < ActiveRecord::TestCase
   end
 
   def test_find_in_batches_should_not_use_records_after_yielding_them_in_case_original_array_is_modified
-    not_a_post = "not a post"
+    not_a_post = "not a post".dup
     def not_a_post.id; end
-    not_a_post.stub(:id, ->{ raise StandardError.new("not_a_post had #id called on it") }) do
+    not_a_post.stub(:id, -> { raise StandardError.new("not_a_post had #id called on it") }) do
       assert_nothing_raised do
-        Post.find_in_batches(:batch_size => 1) do |batch|
+        Post.find_in_batches(batch_size: 1) do |batch|
           assert_kind_of Array, batch
           assert_kind_of Post, batch.first
 
@@ -166,37 +183,37 @@ class EachTest < ActiveRecord::TestCase
 
   def test_find_in_batches_should_error_on_ignore_the_order
     assert_raise(ArgumentError) do
-      PostWithDefaultScope.find_in_batches(error_on_ignore: true){}
+      PostWithDefaultScope.find_in_batches(error_on_ignore: true) {}
     end
   end
 
   def test_find_in_batches_should_not_error_if_config_overridden
     # Set the config option which will be overridden
-    prev = ActiveRecord::Base.error_on_ignored_order_or_limit
-    ActiveRecord::Base.error_on_ignored_order_or_limit = true
+    prev = ActiveRecord::Base.error_on_ignored_order
+    ActiveRecord::Base.error_on_ignored_order = true
     assert_nothing_raised do
-      PostWithDefaultScope.find_in_batches(error_on_ignore: false){}
+      PostWithDefaultScope.find_in_batches(error_on_ignore: false) {}
     end
   ensure
     # Set back to default
-    ActiveRecord::Base.error_on_ignored_order_or_limit = prev
+    ActiveRecord::Base.error_on_ignored_order = prev
   end
 
   def test_find_in_batches_should_error_on_config_specified_to_error
     # Set the config option
-    prev = ActiveRecord::Base.error_on_ignored_order_or_limit
-    ActiveRecord::Base.error_on_ignored_order_or_limit = true
+    prev = ActiveRecord::Base.error_on_ignored_order
+    ActiveRecord::Base.error_on_ignored_order = true
     assert_raise(ArgumentError) do
-      PostWithDefaultScope.find_in_batches(){}
+      PostWithDefaultScope.find_in_batches() {}
     end
   ensure
     # Set back to default
-    ActiveRecord::Base.error_on_ignored_order_or_limit = prev
+    ActiveRecord::Base.error_on_ignored_order = prev
   end
 
   def test_find_in_batches_should_not_error_by_default
     assert_nothing_raised do
-      PostWithDefaultScope.find_in_batches(){}
+      PostWithDefaultScope.find_in_batches() {}
     end
   end
 
@@ -211,12 +228,12 @@ class EachTest < ActiveRecord::TestCase
 
   def test_find_in_batches_should_not_modify_passed_options
     assert_nothing_raised do
-      Post.find_in_batches({ batch_size: 42, start: 1 }.freeze){}
+      Post.find_in_batches({ batch_size: 42, start: 1 }.freeze) {}
     end
   end
 
   def test_find_in_batches_should_use_any_column_as_primary_key
-    nick_order_subscribers = Subscriber.order('nick asc')
+    nick_order_subscribers = Subscriber.order("nick asc")
     start_nick = nick_order_subscribers.second.nick
 
     subscribers = []
@@ -239,7 +256,7 @@ class EachTest < ActiveRecord::TestCase
   def test_find_in_batches_should_return_an_enumerator
     enum = nil
     assert_no_queries do
-      enum = Post.find_in_batches(:batch_size => 1)
+      enum = Post.find_in_batches(batch_size: 1)
     end
     assert_queries(4) do
       enum.first(4) do |batch|
@@ -249,6 +266,28 @@ class EachTest < ActiveRecord::TestCase
     end
   end
 
+  test "find_in_batches should honor limit if passed a block" do
+    limit = @total - 1
+    total = 0
+
+    Post.limit(limit).find_in_batches do |batch|
+      total += batch.size
+    end
+
+    assert_equal limit, total
+  end
+
+  test "find_in_batches should honor limit if no block is passed" do
+    limit = @total - 1
+    total = 0
+
+    Post.limit(limit).find_in_batches.each do |batch|
+      total += batch.size
+    end
+
+    assert_equal limit, total
+  end
+
   def test_in_batches_should_not_execute_any_query
     assert_no_queries do
       assert_kind_of ActiveRecord::Batches::BatchEnumerator, Post.in_batches(of: 2)
@@ -290,7 +329,7 @@ class EachTest < ActiveRecord::TestCase
   end
 
   def test_in_batches_each_record_should_be_ordered_by_id
-    ids = Post.order('id ASC').pluck(:id)
+    ids = Post.order("id ASC").pluck(:id)
     assert_queries(6) do
       Post.in_batches(of: 2).each_record.with_index do |post, i|
         assert_equal ids[i], post.id
@@ -306,9 +345,9 @@ class EachTest < ActiveRecord::TestCase
   end
 
   def test_in_batches_delete_all_should_not_delete_records_in_other_batches
-    not_deleted_count = Post.where('id <= 2').count
-    Post.where('id > 2').in_batches(of: 2).delete_all
-    assert_equal 0, Post.where('id > 2').count
+    not_deleted_count = Post.where("id <= 2").count
+    Post.where("id > 2").in_batches(of: 2).delete_all
+    assert_equal 0, Post.where("id > 2").count
     assert_equal not_deleted_count, Post.count
   end
 
@@ -345,7 +384,7 @@ class EachTest < ActiveRecord::TestCase
   end
 
   def test_in_batches_should_start_from_the_start_option
-    post = Post.order('id ASC').where('id >= ?', 2).first
+    post = Post.order("id ASC").where("id >= ?", 2).first
     assert_queries(2) do
       relation = Post.in_batches(of: 1, start: 2).first
       assert_equal post, relation.first
@@ -353,7 +392,7 @@ class EachTest < ActiveRecord::TestCase
   end
 
   def test_in_batches_should_end_at_the_finish_option
-    post = Post.order('id DESC').where('id <= ?', 5).first
+    post = Post.order("id DESC").where("id <= ?", 5).first
     assert_queries(7) do
       relation = Post.in_batches(of: 1, finish: 5, load: true).reverse_each.first
       assert_equal post, relation.last
@@ -372,7 +411,7 @@ class EachTest < ActiveRecord::TestCase
 
   def test_in_batches_should_quote_batch_order
     c = Post.connection
-    assert_sql(/ORDER BY #{c.quote_table_name('posts')}.#{c.quote_column_name('id')}/) do
+    assert_sql(/ORDER BY #{c.quote_table_name('posts')}\.#{c.quote_column_name('id')}/) do
       Post.in_batches(of: 1) do |relation|
         assert_kind_of ActiveRecord::Relation, relation
         assert_kind_of Post, relation.first
@@ -381,7 +420,7 @@ class EachTest < ActiveRecord::TestCase
   end
 
   def test_in_batches_should_not_use_records_after_yielding_them_in_case_original_array_is_modified
-    not_a_post = "not a post"
+    not_a_post = "not a post".dup
     def not_a_post.id
       raise StandardError.new("not_a_post had #id called on it")
     end
@@ -407,12 +446,12 @@ class EachTest < ActiveRecord::TestCase
 
   def test_in_batches_should_not_modify_passed_options
     assert_nothing_raised do
-      Post.in_batches({ of: 42, start: 1 }.freeze){}
+      Post.in_batches({ of: 42, start: 1 }.freeze) {}
     end
   end
 
   def test_in_batches_should_use_any_column_as_primary_key
-    nick_order_subscribers = Subscriber.order('nick asc')
+    nick_order_subscribers = Subscriber.order("nick asc")
     start_nick = nick_order_subscribers.second.nick
 
     subscribers = []
@@ -472,18 +511,149 @@ class EachTest < ActiveRecord::TestCase
     person.update_attributes(author_id: 1)
 
     Post.in_batches(of: 2) do |batch|
-      batch.where('author_id >= 1').update_all('author_id = author_id + 1')
+      batch.where("author_id >= 1").update_all("author_id = author_id + 1")
     end
     assert_equal 2, person.reload.author_id # incremented only once
   end
 
-  if Enumerator.method_defined? :size
-    def test_find_in_batches_should_return_a_sized_enumerator
-      assert_equal 11, Post.find_in_batches(:batch_size => 1).size
-      assert_equal 6, Post.find_in_batches(:batch_size => 2).size
-      assert_equal 4, Post.find_in_batches(batch_size: 2, start: 4).size
-      assert_equal 4, Post.find_in_batches(:batch_size => 3).size
-      assert_equal 1, Post.find_in_batches(:batch_size => 10_000).size
+  def test_find_in_batches_should_return_a_sized_enumerator
+    assert_equal 11, Post.find_in_batches(batch_size: 1).size
+    assert_equal 6, Post.find_in_batches(batch_size: 2).size
+    assert_equal 4, Post.find_in_batches(batch_size: 2, start: 4).size
+    assert_equal 4, Post.find_in_batches(batch_size: 3).size
+    assert_equal 1, Post.find_in_batches(batch_size: 10_000).size
+  end
+
+  [true, false].each do |load|
+    test "in_batches should return limit records when limit is less than batch size and load is #{load}" do
+      limit      = 3
+      batch_size = 5
+      total      = 0
+
+      Post.limit(limit).in_batches(of: batch_size, load: load) do |batch|
+        total += batch.count
+      end
+
+      assert_equal limit, total
+    end
+
+    test "in_batches should return limit records when limit is greater than batch size and load is #{load}" do
+      limit      = 5
+      batch_size = 3
+      total      = 0
+
+      Post.limit(limit).in_batches(of: batch_size, load: load) do |batch|
+        total += batch.count
+      end
+
+      assert_equal limit, total
+    end
+
+    test "in_batches should return limit records when limit is a multiple of the batch size and load is #{load}" do
+      limit      = 6
+      batch_size = 3
+      total      = 0
+
+      Post.limit(limit).in_batches(of: batch_size, load: load) do |batch|
+        total += batch.count
+      end
+
+      assert_equal limit, total
+    end
+
+    test "in_batches should return no records if the limit is 0 and load is #{load}" do
+      limit      = 0
+      batch_size = 1
+      total      = 0
+
+      Post.limit(limit).in_batches(of: batch_size, load: load) do |batch|
+        total += batch.count
+      end
+
+      assert_equal limit, total
+    end
+
+    test "in_batches should return all if the limit is greater than the number of records when load is #{load}" do
+      limit      = @total + 1
+      batch_size = 1
+      total      = 0
+
+      Post.limit(limit).in_batches(of: batch_size, load: load) do |batch|
+        total += batch.count
+      end
+
+      assert_equal @total, total
+    end
+  end
+
+  test ".find_each respects table alias" do
+    assert_queries(1) do
+      table_alias = Post.arel_table.alias("omg_posts")
+      table_metadata = ActiveRecord::TableMetadata.new(Post, table_alias)
+      predicate_builder = ActiveRecord::PredicateBuilder.new(table_metadata)
+
+      posts = ActiveRecord::Relation.create(Post, table_alias, predicate_builder)
+      posts.find_each {}
+    end
+  end
+
+  test ".find_each bypasses the query cache for its own queries" do
+    Post.cache do
+      assert_queries(2) do
+        Post.find_each {}
+        Post.find_each {}
+      end
+    end
+  end
+
+  test ".find_each does not disable the query cache inside the given block" do
+    Post.cache do
+      Post.find_each(start: 1, finish: 1) do |post|
+        assert_queries(1) do
+          post.comments.count
+          post.comments.count
+        end
+      end
+    end
+  end
+
+  test ".find_in_batches bypasses the query cache for its own queries" do
+    Post.cache do
+      assert_queries(2) do
+        Post.find_in_batches {}
+        Post.find_in_batches {}
+      end
+    end
+  end
+
+  test ".find_in_batches does not disable the query cache inside the given block" do
+    Post.cache do
+      Post.find_in_batches(start: 1, finish: 1) do |batch|
+        assert_queries(1) do
+          batch.first.comments.count
+          batch.first.comments.count
+        end
+      end
+    end
+  end
+
+  test ".in_batches bypasses the query cache for its own queries" do
+    Post.cache do
+      assert_queries(2) do
+        Post.in_batches {}
+        Post.in_batches {}
+      end
+    end
+  end
+
+  test ".in_batches does not disable the query cache inside the given block" do
+    Post.cache do
+      Post.in_batches(start: 1, finish: 1) do |relation|
+        assert_queries(1) do
+          relation.count
+          relation.count
+        end
+      end
     end
   end
 end
diff --git a/activerecord/test/cases/binary_test.rb b/activerecord/test/cases/binary_test.rb
index 9eb5352150..d5376ece69 100644
--- a/activerecord/test/cases/binary_test.rb
+++ b/activerecord/test/cases/binary_test.rb
@@ -1,26 +1,28 @@
+# frozen_string_literal: true
+
 require "cases/helper"
 
 # Without using prepared statements, it makes no sense to test
 # BLOB data with DB2, because the length of a statement
 # is limited to 32KB.
 unless current_adapter?(:DB2Adapter)
-  require 'models/binary'
+  require "models/binary"
 
   class BinaryTest < ActiveRecord::TestCase
     FIXTURES = %w(flowers.jpg example.log test.txt)
 
     def test_mixed_encoding
-      str = "\x80"
-      str.force_encoding('ASCII-8BIT')
+      str = "\x80".dup
+      str.force_encoding("ASCII-8BIT")
 
-      binary = Binary.new :name => 'いただきます！', :data => str
+      binary = Binary.new name: "いただきます！", data: str
       binary.save!
       binary.reload
       assert_equal str, binary.data
 
       name = binary.name
 
-      assert_equal 'いただきます！', name
+      assert_equal "いただきます！", name
     end
 
     def test_load_save
@@ -28,16 +30,16 @@ unless current_adapter?(:DB2Adapter)
 
       FIXTURES.each do |filename|
         data = File.read(ASSETS_ROOT + "/#{filename}")
-        data.force_encoding('ASCII-8BIT')
+        data.force_encoding("ASCII-8BIT")
         data.freeze
 
-        bin = Binary.new(:data => data)
-        assert_equal data, bin.data, 'Newly assigned data differs from original'
+        bin = Binary.new(data: data)
+        assert_equal data, bin.data, "Newly assigned data differs from original"
 
         bin.save!
-        assert_equal data, bin.data, 'Data differs from original after save'
+        assert_equal data, bin.data, "Data differs from original after save"
 
-        assert_equal data, bin.reload.data, 'Reloaded data differs from original'
+        assert_equal data, bin.reload.data, "Reloaded data differs from original"
       end
     end
   end
diff --git a/activerecord/test/cases/bind_parameter_test.rb b/activerecord/test/cases/bind_parameter_test.rb
index fa924fe4cb..91cc49385c 100644
--- a/activerecord/test/cases/bind_parameter_test.rb
+++ b/activerecord/test/cases/bind_parameter_test.rb
@@ -1,50 +1,51 @@
-require 'cases/helper'
-require 'models/topic'
-require 'models/author'
-require 'models/post'
+# frozen_string_literal: true
 
-module ActiveRecord
-  class BindParameterTest < ActiveRecord::TestCase
-    fixtures :topics, :authors, :posts
+require "cases/helper"
+require "models/topic"
+require "models/author"
+require "models/post"
 
-    class LogListener
-      attr_accessor :calls
+if ActiveRecord::Base.connection.prepared_statements
+  module ActiveRecord
+    class BindParameterTest < ActiveRecord::TestCase
+      fixtures :topics, :authors, :author_addresses, :posts
 
-      def initialize
-        @calls = []
-      end
+      class LogListener
+        attr_accessor :calls
+
+        def initialize
+          @calls = []
+        end
 
-      def call(*args)
-        calls << args
+        def call(*args)
+          calls << args
+        end
       end
-    end
 
-    def setup
-      super
-      @connection = ActiveRecord::Base.connection
-      @subscriber = LogListener.new
-      @pk = Topic.columns_hash[Topic.primary_key]
-      @subscription = ActiveSupport::Notifications.subscribe('sql.active_record', @subscriber)
-    end
+      def setup
+        super
+        @connection = ActiveRecord::Base.connection
+        @subscriber = LogListener.new
+        @pk = Topic.columns_hash[Topic.primary_key]
+        @subscription = ActiveSupport::Notifications.subscribe("sql.active_record", @subscriber)
+      end
 
-    teardown do
-      ActiveSupport::Notifications.unsubscribe(@subscription)
-    end
+      def teardown
+        ActiveSupport::Notifications.unsubscribe(@subscription)
+      end
 
-    if ActiveRecord::Base.connection.supports_statement_cache? &&
-       ActiveRecord::Base.connection.prepared_statements
       def test_bind_from_join_in_subquery
-        subquery = Author.joins(:thinking_posts).where(name: 'David')
-        scope = Author.from(subquery, 'authors').where(id: 1)
+        subquery = Author.joins(:thinking_posts).where(name: "David")
+        scope = Author.from(subquery, "authors").where(id: 1)
         assert_equal 1, scope.count
       end
 
       def test_binds_are_logged
-        sub   = Arel::Nodes::BindParam.new
+        sub   = Arel::Nodes::BindParam.new(1)
         binds = [Relation::QueryAttribute.new("id", 1, Type::Value.new)]
         sql   = "select * from topics where id = #{sub.to_sql}"
 
-        @connection.exec_query(sql, 'SQL', binds)
+        @connection.exec_query(sql, "SQL", binds)
 
         message = @subscriber.calls.find { |args| args[4][:sql] == sql }
         assert_equal binds, message[4][:binds]
@@ -53,37 +54,55 @@ module ActiveRecord
       def test_find_one_uses_binds
         Topic.find(1)
         message = @subscriber.calls.find { |args| args[4][:binds].any? { |attr| attr.value == 1 } }
-        assert message, 'expected a message with binds'
+        assert message, "expected a message with binds"
+      end
+
+      def test_logs_binds_after_type_cast
+        binds = [Relation::QueryAttribute.new("id", "10", Type::Integer.new)]
+        assert_logs_binds(binds)
       end
 
-      def test_logs_bind_vars_after_type_cast
-        payload = {
-          :name  => 'SQL',
-          :sql   => 'select * from topics where id = ?',
-          :binds => [Relation::QueryAttribute.new("id", "10", Type::Integer.new)]
-        }
-        event  = ActiveSupport::Notifications::Event.new(
-          'foo',
-          Time.now,
-          Time.now,
-          123,
-          payload)
-
-        logger = Class.new(ActiveRecord::LogSubscriber) {
-          attr_reader :debugs
-          def initialize
-            super
-            @debugs = []
-          end
-
-          def debug str
-            @debugs << str
-          end
-        }.new
-
-        logger.sql event
-        assert_match([[@pk.name, 10]].inspect, logger.debugs.first)
+      def test_logs_legacy_binds_after_type_cast
+        binds = [[@pk, "10"]]
+        assert_logs_binds(binds)
       end
+
+      def test_deprecate_supports_statement_cache
+        assert_deprecated { ActiveRecord::Base.connection.supports_statement_cache? }
+      end
+
+      private
+        def assert_logs_binds(binds)
+          payload = {
+            name: "SQL",
+            sql: "select * from topics where id = ?",
+            binds: binds,
+            type_casted_binds: @connection.type_casted_binds(binds)
+          }
+
+          event = ActiveSupport::Notifications::Event.new(
+            "foo",
+            Time.now,
+            Time.now,
+            123,
+            payload)
+
+          logger = Class.new(ActiveRecord::LogSubscriber) {
+            attr_reader :debugs
+
+            def initialize
+              super
+              @debugs = []
+            end
+
+            def debug(str)
+              @debugs << str
+            end
+          }.new
+
+          logger.sql(event)
+          assert_match([[@pk.name, 10]].inspect, logger.debugs.first)
+        end
     end
   end
 end
diff --git a/activerecord/test/cases/cache_key_test.rb b/activerecord/test/cases/cache_key_test.rb
index bb2829b3c1..8f2f2c6186 100644
--- a/activerecord/test/cases/cache_key_test.rb
+++ b/activerecord/test/cases/cache_key_test.rb
@@ -1,25 +1,53 @@
+# frozen_string_literal: true
+
 require "cases/helper"
 
 module ActiveRecord
   class CacheKeyTest < ActiveRecord::TestCase
     self.use_transactional_tests = false
 
-    class CacheMe < ActiveRecord::Base; end
+    class CacheMe < ActiveRecord::Base
+      self.cache_versioning = false
+    end
+
+    class CacheMeWithVersion < ActiveRecord::Base
+      self.cache_versioning = true
+    end
 
     setup do
       @connection = ActiveRecord::Base.connection
-      @connection.create_table(:cache_mes) { |t| t.timestamps }
+      @connection.create_table(:cache_mes, force: true) { |t| t.timestamps }
+      @connection.create_table(:cache_me_with_versions, force: true) { |t| t.timestamps }
     end
 
     teardown do
       @connection.drop_table :cache_mes, if_exists: true
+      @connection.drop_table :cache_me_with_versions, if_exists: true
     end
 
-    test "test_cache_key_format_is_not_too_precise" do
+    test "cache_key format is not too precise" do
       record = CacheMe.create
       key = record.cache_key
 
       assert_equal key, record.reload.cache_key
     end
+
+    test "cache_key has no version when versioning is on" do
+      record = CacheMeWithVersion.create
+      assert_equal "active_record/cache_key_test/cache_me_with_versions/#{record.id}", record.cache_key
+    end
+
+    test "cache_version is only there when versioning is on" do
+      assert CacheMeWithVersion.create.cache_version.present?
+      assert_not CacheMe.create.cache_version.present?
+    end
+
+    test "cache_key_with_version always has both key and version" do
+      r1 = CacheMeWithVersion.create
+      assert_equal "active_record/cache_key_test/cache_me_with_versions/#{r1.id}-#{r1.updated_at.to_s(:usec)}", r1.cache_key_with_version
+
+      r2 = CacheMe.create
+      assert_equal "active_record/cache_key_test/cache_mes/#{r2.id}-#{r2.updated_at.to_s(:usec)}", r2.cache_key_with_version
+    end
   end
 end
diff --git a/activerecord/test/cases/calculations_test.rb b/activerecord/test/cases/calculations_test.rb
index cfae700159..5eda39a0c7 100644
--- a/activerecord/test/cases/calculations_test.rb
+++ b/activerecord/test/cases/calculations_test.rb
@@ -1,31 +1,27 @@
+# frozen_string_literal: true
+
 require "cases/helper"
-require 'models/club'
-require 'models/company'
+require "models/book"
+require "models/club"
+require "models/company"
 require "models/contract"
-require 'models/edge'
-require 'models/organization'
-require 'models/possession'
-require 'models/topic'
-require 'models/reply'
-require 'models/minivan'
-require 'models/speedometer'
-require 'models/ship_part'
-require 'models/treasure'
-require 'models/developer'
-require 'models/comment'
-require 'models/rating'
-require 'models/post'
-
-class NumericData < ActiveRecord::Base
-  self.table_name = 'numeric_data'
-
-  attribute :world_population, :integer
-  attribute :my_house_population, :integer
-  attribute :atoms_in_universe, :integer
-end
+require "models/edge"
+require "models/organization"
+require "models/possession"
+require "models/topic"
+require "models/reply"
+require "models/numeric_data"
+require "models/minivan"
+require "models/speedometer"
+require "models/ship_part"
+require "models/treasure"
+require "models/developer"
+require "models/post"
+require "models/comment"
+require "models/rating"
 
 class CalculationsTest < ActiveRecord::TestCase
-  fixtures :companies, :accounts, :topics, :speedometers, :minivans
+  fixtures :companies, :accounts, :topics, :speedometers, :minivans, :books
 
   def test_should_sum_field
     assert_equal 318, Account.sum(:credit_limit)
@@ -56,7 +52,7 @@ class CalculationsTest < ActiveRecord::TestCase
 
   def test_should_return_integer_average_if_db_returns_such
     ShipPart.delete_all
-    ShipPart.create!(:id => 3, :name => 'foo')
+    ShipPart.create!(id: 3, name: "foo")
     value = ShipPart.average(:id)
     assert_equal 3, value
   end
@@ -91,25 +87,25 @@ class CalculationsTest < ActiveRecord::TestCase
 
   def test_should_group_by_field
     c = Account.group(:firm_id).sum(:credit_limit)
-    [1,6,2].each do |firm_id|
-      assert c.keys.include?(firm_id), "Group #{c.inspect} does not contain firm_id #{firm_id}"
+    [1, 6, 2].each do |firm_id|
+      assert_includes c.keys, firm_id, "Group #{c.inspect} does not contain firm_id #{firm_id}"
     end
   end
 
   def test_should_group_by_arel_attribute
     c = Account.group(Account.arel_table[:firm_id]).sum(:credit_limit)
-    [1,6,2].each do |firm_id|
-      assert c.keys.include?(firm_id), "Group #{c.inspect} does not contain firm_id #{firm_id}"
+    [1, 6, 2].each do |firm_id|
+      assert_includes c.keys, firm_id, "Group #{c.inspect} does not contain firm_id #{firm_id}"
     end
   end
 
   def test_should_group_by_multiple_fields
-    c = Account.group('firm_id', :credit_limit).count(:all)
-    [ [nil, 50], [1, 50], [6, 50], [6, 55], [9, 53], [2, 60] ].each { |firm_and_limit| assert c.keys.include?(firm_and_limit) }
+    c = Account.group("firm_id", :credit_limit).count(:all)
+    [ [nil, 50], [1, 50], [6, 50], [6, 55], [9, 53], [2, 60] ].each { |firm_and_limit| assert_includes c.keys, firm_and_limit }
   end
 
   def test_should_group_by_multiple_fields_having_functions
-    c = Topic.group(:author_name, 'COALESCE(type, title)').count(:all)
+    c = Topic.group(:author_name, "COALESCE(type, title)").count(:all)
     assert_equal 1, c[["Carl", "The Third Topic of the day"]]
     assert_equal 1, c[["Mary", "Reply"]]
     assert_equal 1, c[["David", "The First Topic"]]
@@ -165,14 +161,14 @@ class CalculationsTest < ActiveRecord::TestCase
   end
 
   def test_limit_should_apply_before_count
-    accounts = Account.limit(3).where('firm_id IS NOT NULL')
+    accounts = Account.limit(4)
 
     assert_equal 3, accounts.count(:firm_id)
     assert_equal 3, accounts.select(:firm_id).count
   end
 
   def test_limit_should_apply_before_count_arel_attribute
-    accounts = Account.limit(3).where('firm_id IS NOT NULL')
+    accounts = Account.limit(4)
 
     firm_id_attribute = Account.arel_table[:firm_id]
     assert_equal 3, accounts.count(firm_id_attribute)
@@ -226,15 +222,64 @@ class CalculationsTest < ActiveRecord::TestCase
     assert_match "credit_limit, firm_name", e.message
   end
 
+  def test_apply_distinct_in_count
+    queries = assert_sql do
+      Account.distinct.count
+      Account.group(:firm_id).distinct.count
+    end
+
+    queries.each do |query|
+      # `table_alias_length` in `column_alias_for` would execute
+      # "SHOW max_identifier_length" statement in PostgreSQL adapter.
+      next if query == "SHOW max_identifier_length"
+      assert_match %r{\ASELECT(?! DISTINCT) COUNT\(DISTINCT\b}, query
+    end
+  end
+
+  def test_distinct_count_all_with_custom_select_and_order
+    accounts = Account.distinct.select("credit_limit % 10").order(Arel.sql("credit_limit % 10"))
+    assert_queries(1) { assert_equal 3, accounts.count(:all) }
+    assert_queries(1) { assert_equal 3, accounts.load.size }
+  end
+
+  def test_distinct_count_with_order_and_limit
+    assert_equal 4, Account.distinct.order(:firm_id).limit(4).count
+  end
+
+  def test_distinct_count_with_order_and_offset
+    assert_equal 4, Account.distinct.order(:firm_id).offset(2).count
+  end
+
+  def test_distinct_count_with_order_and_limit_and_offset
+    assert_equal 4, Account.distinct.order(:firm_id).limit(4).offset(2).count
+  end
+
+  def test_distinct_joins_count_with_order_and_limit
+    assert_equal 3, Account.joins(:firm).distinct.order(:firm_id).limit(3).count
+  end
+
+  def test_distinct_joins_count_with_order_and_offset
+    assert_equal 3, Account.joins(:firm).distinct.order(:firm_id).offset(2).count
+  end
+
+  def test_distinct_joins_count_with_order_and_limit_and_offset
+    assert_equal 3, Account.joins(:firm).distinct.order(:firm_id).limit(3).offset(2).count
+  end
+
+  def test_distinct_count_with_group_by_and_order_and_limit
+    assert_equal({ 6 => 2 }, Account.group(:firm_id).distinct.order("1 DESC").limit(1).count)
+  end
+
   def test_should_group_by_summed_field_having_condition
-    c = Account.group(:firm_id).having('sum(credit_limit) > 50').sum(:credit_limit)
+    c = Account.group(:firm_id).having("sum(credit_limit) > 50").sum(:credit_limit)
     assert_nil        c[1]
     assert_equal 105, c[6]
     assert_equal 60,  c[2]
   end
 
   def test_should_group_by_summed_field_having_condition_from_select
-    c = Account.select("MIN(credit_limit) AS min_credit_limit").group(:firm_id).having("MIN(credit_limit) > 50").sum(:credit_limit)
+    skip unless current_adapter?(:Mysql2Adapter, :SQLite3Adapter)
+    c = Account.select("MIN(credit_limit) AS min_credit_limit").group(:firm_id).having("min_credit_limit > 50").sum(:credit_limit)
     assert_nil       c[1]
     assert_equal 60, c[2]
     assert_equal 53, c[9]
@@ -248,52 +293,52 @@ class CalculationsTest < ActiveRecord::TestCase
   end
 
   def test_should_sum_field_with_conditions
-    assert_equal 105, Account.where('firm_id = 6').sum(:credit_limit)
+    assert_equal 105, Account.where("firm_id = 6").sum(:credit_limit)
   end
 
   def test_should_return_zero_if_sum_conditions_return_nothing
-    assert_equal 0, Account.where('1 = 2').sum(:credit_limit)
-    assert_equal 0, companies(:rails_core).companies.where('1 = 2').sum(:id)
+    assert_equal 0, Account.where("1 = 2").sum(:credit_limit)
+    assert_equal 0, companies(:rails_core).companies.where("1 = 2").sum(:id)
   end
 
   def test_sum_should_return_valid_values_for_decimals
-    NumericData.create(:bank_balance => 19.83)
+    NumericData.create(bank_balance: 19.83)
     assert_equal 19.83, NumericData.sum(:bank_balance)
   end
 
   def test_should_return_type_casted_values_with_group_and_expression
-    assert_equal 0.5, Account.group(:firm_name).sum('0.01 * credit_limit')['37signals']
+    assert_equal 0.5, Account.group(:firm_name).sum("0.01 * credit_limit")["37signals"]
   end
 
   def test_should_group_by_summed_field_with_conditions
-    c = Account.where('firm_id > 1').group(:firm_id).sum(:credit_limit)
+    c = Account.where("firm_id > 1").group(:firm_id).sum(:credit_limit)
     assert_nil        c[1]
     assert_equal 105, c[6]
     assert_equal 60,  c[2]
   end
 
   def test_should_group_by_summed_field_with_conditions_and_having
-    c = Account.where('firm_id > 1').group(:firm_id).
-     having('sum(credit_limit) > 60').sum(:credit_limit)
+    c = Account.where("firm_id > 1").group(:firm_id).
+     having("sum(credit_limit) > 60").sum(:credit_limit)
     assert_nil        c[1]
     assert_equal 105, c[6]
     assert_nil        c[2]
   end
 
   def test_should_group_by_fields_with_table_alias
-    c = Account.group('accounts.firm_id').sum(:credit_limit)
+    c = Account.group("accounts.firm_id").sum(:credit_limit)
     assert_equal 50,  c[1]
     assert_equal 105, c[6]
     assert_equal 60,  c[2]
   end
 
   def test_should_calculate_with_invalid_field
-    assert_equal 6, Account.calculate(:count, '*')
+    assert_equal 6, Account.calculate(:count, "*")
     assert_equal 6, Account.calculate(:count, :all)
   end
 
   def test_should_calculate_grouped_with_invalid_field
-    c = Account.group('accounts.firm_id').count(:all)
+    c = Account.group("accounts.firm_id").count(:all)
     assert_equal 1, c[1]
     assert_equal 2, c[6]
     assert_equal 1, c[2]
@@ -307,8 +352,8 @@ class CalculationsTest < ActiveRecord::TestCase
   end
 
   def test_should_group_by_association_with_non_numeric_foreign_key
-    Speedometer.create! id: 'ABC'
-    Minivan.create! id: 'OMG', speedometer_id: 'ABC'
+    Speedometer.create! id: "ABC"
+    Minivan.create! id: "OMG", speedometer_id: "ABC"
 
     c = Minivan.group(:speedometer).count(:all)
     first_key = c.keys.first
@@ -317,7 +362,7 @@ class CalculationsTest < ActiveRecord::TestCase
   end
 
   def test_should_calculate_grouped_association_with_foreign_key_option
-    Account.belongs_to :another_firm, :class_name => 'Firm', :foreign_key => 'firm_id'
+    Account.belongs_to :another_firm, class_name: "Firm", foreign_key: "firm_id"
     c = Account.group(:another_firm).count(:all)
     assert_equal 1, c[companies(:first_firm)]
     assert_equal 2, c[companies(:rails_core)]
@@ -327,17 +372,17 @@ class CalculationsTest < ActiveRecord::TestCase
   def test_should_calculate_grouped_by_function
     c = Company.group("UPPER(#{QUOTED_TYPE})").count(:all)
     assert_equal 2, c[nil]
-    assert_equal 1, c['DEPENDENTFIRM']
-    assert_equal 5, c['CLIENT']
-    assert_equal 2, c['FIRM']
+    assert_equal 1, c["DEPENDENTFIRM"]
+    assert_equal 5, c["CLIENT"]
+    assert_equal 2, c["FIRM"]
   end
 
   def test_should_calculate_grouped_by_function_with_table_alias
     c = Company.group("UPPER(companies.#{QUOTED_TYPE})").count(:all)
     assert_equal 2, c[nil]
-    assert_equal 1, c['DEPENDENTFIRM']
-    assert_equal 5, c['CLIENT']
-    assert_equal 2, c['FIRM']
+    assert_equal 1, c["DEPENDENTFIRM"]
+    assert_equal 5, c["CLIENT"]
+    assert_equal 2, c["FIRM"]
   end
 
   def test_should_not_overshadow_enumerable_sum
@@ -353,19 +398,19 @@ class CalculationsTest < ActiveRecord::TestCase
   end
 
   def test_should_sum_scoped_field_with_conditions
-    assert_equal 8,  companies(:rails_core).companies.where('id > 7').sum(:id)
+    assert_equal 8,  companies(:rails_core).companies.where("id > 7").sum(:id)
   end
 
   def test_should_group_by_scoped_field
     c = companies(:rails_core).companies.group(:name).sum(:id)
-    assert_equal 7, c['Leetsoft']
-    assert_equal 8, c['Jadedpixel']
+    assert_equal 7, c["Leetsoft"]
+    assert_equal 8, c["Jadedpixel"]
   end
 
   def test_should_group_by_summed_field_through_association_and_having
-    c = companies(:rails_core).companies.group(:name).having('sum(id) > 7').sum(:id)
-    assert_nil      c['Leetsoft']
-    assert_equal 8, c['Jadedpixel']
+    c = companies(:rails_core).companies.group(:name).having("sum(id) > 7").sum(:id)
+    assert_nil      c["Leetsoft"]
+    assert_equal 8, c["Jadedpixel"]
   end
 
   def test_should_count_selected_field_with_include
@@ -380,7 +425,7 @@ class CalculationsTest < ActiveRecord::TestCase
   end
 
   def test_should_perform_joined_include_when_referencing_included_tables
-    joined_count = Account.includes(:firm).where(:companies => {:name => '37signals'}).count
+    joined_count = Account.includes(:firm).where(companies: { name: "37signals" }).count
     assert_equal 1, joined_count
   end
 
@@ -391,10 +436,10 @@ class CalculationsTest < ActiveRecord::TestCase
 
   def test_should_count_scoped_select_with_options
     Account.update_all("credit_limit = NULL")
-    Account.last.update_columns('credit_limit' => 49)
-    Account.first.update_columns('credit_limit' => 51)
+    Account.last.update_columns("credit_limit" => 49)
+    Account.first.update_columns("credit_limit" => 51)
 
-    assert_equal 1, Account.select("credit_limit").where('credit_limit >= 50').count
+    assert_equal 1, Account.select("credit_limit").where("credit_limit >= 50").count
   end
 
   def test_should_count_manual_select_with_include
@@ -420,10 +465,6 @@ class CalculationsTest < ActiveRecord::TestCase
 
   def test_count_with_distinct
     assert_equal 4, Account.select(:credit_limit).distinct.count
-
-    assert_deprecated do
-      assert_equal 4, Account.select(:credit_limit).uniq.count
-    end
   end
 
   def test_count_with_aliased_attribute
@@ -435,8 +476,8 @@ class CalculationsTest < ActiveRecord::TestCase
   end
 
   def test_should_count_field_in_joined_table
-    assert_equal 5, Account.joins(:firm).count('companies.id')
-    assert_equal 4, Account.joins(:firm).distinct.count('companies.id')
+    assert_equal 5, Account.joins(:firm).count("companies.id")
+    assert_equal 4, Account.joins(:firm).distinct.count("companies.id")
   end
 
   def test_count_arel_attribute_in_joined_table_with
@@ -450,14 +491,14 @@ class CalculationsTest < ActiveRecord::TestCase
   end
 
   def test_should_count_field_in_joined_table_with_group_by
-    c = Account.group('accounts.firm_id').joins(:firm).count('companies.id')
+    c = Account.group("accounts.firm_id").joins(:firm).count("companies.id")
 
-    [1,6,2,9].each { |firm_id| assert c.keys.include?(firm_id) }
+    [1, 6, 2, 9].each { |firm_id| assert_includes c.keys, firm_id }
   end
 
   def test_should_count_field_of_root_table_with_conflicting_group_by_column
     assert_equal({ 1 => 1 }, Firm.joins(:accounts).group(:firm_id).count)
-    assert_equal({ 1 => 1 }, Firm.joins(:accounts).group('accounts.firm_id').count)
+    assert_equal({ 1 => 1 }, Firm.joins(:accounts).group("accounts.firm_id").count)
   end
 
   def test_count_with_no_parameters_isnt_deprecated
@@ -477,9 +518,9 @@ class CalculationsTest < ActiveRecord::TestCase
   end
 
   def test_count_with_where_and_order
-    assert_equal 1, Account.where(firm_name: '37signals').count
-    assert_equal 1, Account.where(firm_name: '37signals').order(:firm_name).count
-    assert_equal 1, Account.where(firm_name: '37signals').order(:firm_name).reverse_order.count
+    assert_equal 1, Account.where(firm_name: "37signals").count
+    assert_equal 1, Account.where(firm_name: "37signals").order(:firm_name).count
+    assert_equal 1, Account.where(firm_name: "37signals").order(:firm_name).reverse_order.count
   end
 
   def test_count_with_block
@@ -487,8 +528,7 @@ class CalculationsTest < ActiveRecord::TestCase
   end
 
   def test_should_sum_expression
-    # Oracle adapter returns floating point value 636.0 after SUM
-    if current_adapter?(:OracleAdapter)
+    if current_adapter?(:SQLite3Adapter, :Mysql2Adapter, :PostgreSQLAdapter, :OracleAdapter)
       assert_equal 636, Account.sum("2 * credit_limit")
     else
       assert_equal 636, Account.sum("2 * credit_limit").to_i
@@ -496,69 +536,69 @@ class CalculationsTest < ActiveRecord::TestCase
   end
 
   def test_sum_expression_returns_zero_when_no_records_to_sum
-    assert_equal 0, Account.where('1 = 2').sum("2 * credit_limit")
+    assert_equal 0, Account.where("1 = 2").sum("2 * credit_limit")
   end
 
   def test_count_with_from_option
-    assert_equal Company.count(:all), Company.from('companies').count(:all)
+    assert_equal Company.count(:all), Company.from("companies").count(:all)
     assert_equal Account.where("credit_limit = 50").count(:all),
-        Account.from('accounts').where("credit_limit = 50").count(:all)
-    assert_equal Company.where(:type => "Firm").count(:type),
-        Company.where(:type => "Firm").from('companies').count(:type)
+        Account.from("accounts").where("credit_limit = 50").count(:all)
+    assert_equal Company.where(type: "Firm").count(:type),
+        Company.where(type: "Firm").from("companies").count(:type)
   end
 
   def test_sum_with_from_option
-    assert_equal Account.sum(:credit_limit), Account.from('accounts').sum(:credit_limit)
+    assert_equal Account.sum(:credit_limit), Account.from("accounts").sum(:credit_limit)
     assert_equal Account.where("credit_limit > 50").sum(:credit_limit),
-        Account.where("credit_limit > 50").from('accounts').sum(:credit_limit)
+        Account.where("credit_limit > 50").from("accounts").sum(:credit_limit)
   end
 
   def test_average_with_from_option
-    assert_equal Account.average(:credit_limit), Account.from('accounts').average(:credit_limit)
+    assert_equal Account.average(:credit_limit), Account.from("accounts").average(:credit_limit)
     assert_equal Account.where("credit_limit > 50").average(:credit_limit),
-        Account.where("credit_limit > 50").from('accounts').average(:credit_limit)
+        Account.where("credit_limit > 50").from("accounts").average(:credit_limit)
   end
 
   def test_minimum_with_from_option
-    assert_equal Account.minimum(:credit_limit), Account.from('accounts').minimum(:credit_limit)
+    assert_equal Account.minimum(:credit_limit), Account.from("accounts").minimum(:credit_limit)
     assert_equal Account.where("credit_limit > 50").minimum(:credit_limit),
-        Account.where("credit_limit > 50").from('accounts').minimum(:credit_limit)
+        Account.where("credit_limit > 50").from("accounts").minimum(:credit_limit)
   end
 
   def test_maximum_with_from_option
-    assert_equal Account.maximum(:credit_limit), Account.from('accounts').maximum(:credit_limit)
+    assert_equal Account.maximum(:credit_limit), Account.from("accounts").maximum(:credit_limit)
     assert_equal Account.where("credit_limit > 50").maximum(:credit_limit),
-        Account.where("credit_limit > 50").from('accounts').maximum(:credit_limit)
+        Account.where("credit_limit > 50").from("accounts").maximum(:credit_limit)
   end
 
   def test_maximum_with_not_auto_table_name_prefix_if_column_included
-    Company.create!(:name => "test", :contracts => [Contract.new(:developer_id => 7)])
+    Company.create!(name: "test", contracts: [Contract.new(developer_id: 7)])
 
     assert_equal 7, Company.includes(:contracts).maximum(:developer_id)
   end
 
   def test_minimum_with_not_auto_table_name_prefix_if_column_included
-    Company.create!(:name => "test", :contracts => [Contract.new(:developer_id => 7)])
+    Company.create!(name: "test", contracts: [Contract.new(developer_id: 7)])
 
     assert_equal 7, Company.includes(:contracts).minimum(:developer_id)
   end
 
   def test_sum_with_not_auto_table_name_prefix_if_column_included
-    Company.create!(:name => "test", :contracts => [Contract.new(:developer_id => 7)])
+    Company.create!(name: "test", contracts: [Contract.new(developer_id: 7)])
 
     assert_equal 7, Company.includes(:contracts).sum(:developer_id)
   end
 
   if current_adapter?(:Mysql2Adapter)
     def test_from_option_with_specified_index
-      assert_equal Edge.count(:all), Edge.from('edges USE INDEX(unique_edge_index)').count(:all)
-      assert_equal Edge.where('sink_id < 5').count(:all),
-          Edge.from('edges USE INDEX(unique_edge_index)').where('sink_id < 5').count(:all)
+      assert_equal Edge.count(:all), Edge.from("edges USE INDEX(unique_edge_index)").count(:all)
+      assert_equal Edge.where("sink_id < 5").count(:all),
+          Edge.from("edges USE INDEX(unique_edge_index)").where("sink_id < 5").count(:all)
     end
   end
 
   def test_from_option_with_table_different_than_class
-    assert_equal Account.count(:all), Company.from('accounts').count(:all)
+    assert_equal Account.count(:all), Company.from("accounts").count(:all)
   end
 
   def test_distinct_is_honored_when_used_with_count_operation_after_group
@@ -571,17 +611,20 @@ class CalculationsTest < ActiveRecord::TestCase
   end
 
   def test_pluck
-    assert_equal [1,2,3,4,5], Topic.order(:id).pluck(:id)
+    assert_equal [1, 2, 3, 4, 5], Topic.order(:id).pluck(:id)
   end
 
   def test_pluck_without_column_names
-    assert_equal [[1, "Firm", 1, nil, "37signals", nil, 1, nil, ""]],
-      Company.order(:id).limit(1).pluck
+    if current_adapter?(:OracleAdapter)
+      assert_equal [[1, "Firm", 1, nil, "37signals", nil, 1, nil, nil]], Company.order(:id).limit(1).pluck
+    else
+      assert_equal [[1, "Firm", 1, nil, "37signals", nil, 1, nil, ""]], Company.order(:id).limit(1).pluck
+    end
   end
 
   def test_pluck_type_cast
     topic = topics(:first)
-    relation = Topic.where(:id => topic.id)
+    relation = Topic.where(id: topic.id)
     assert_equal [ topic.approved ], relation.pluck(:approved)
     assert_equal [ topic.last_read ], relation.pluck(:last_read)
     assert_equal [ topic.written_on ], relation.pluck(:written_on)
@@ -598,42 +641,42 @@ class CalculationsTest < ActiveRecord::TestCase
   end
 
   def test_pluck_on_aliased_attribute
-    assert_equal 'The First Topic', Topic.order(:id).pluck(:heading).first
+    assert_equal "The First Topic", Topic.order(:id).pluck(:heading).first
   end
 
   def test_pluck_with_serialization
-    t = Topic.create!(:content => { :foo => :bar })
-    assert_equal [{:foo => :bar}], Topic.where(:id => t.id).pluck(:content)
+    t = Topic.create!(content: { foo: :bar })
+    assert_equal [{ foo: :bar }], Topic.where(id: t.id).pluck(:content)
   end
 
   def test_pluck_with_qualified_column_name
-    assert_equal [1,2,3,4,5], Topic.order(:id).pluck("topics.id")
+    assert_equal [1, 2, 3, 4, 5], Topic.order(:id).pluck("topics.id")
   end
 
   def test_pluck_auto_table_name_prefix
-    c = Company.create!(:name => "test", :contracts => [Contract.new])
+    c = Company.create!(name: "test", contracts: [Contract.new])
     assert_equal [c.id], Company.joins(:contracts).pluck(:id)
   end
 
   def test_pluck_if_table_included
-    c = Company.create!(:name => "test", :contracts => [Contract.new(:developer_id => 7)])
+    c = Company.create!(name: "test", contracts: [Contract.new(developer_id: 7)])
     assert_equal [c.id], Company.includes(:contracts).where("contracts.id" => c.contracts.first).pluck(:id)
   end
 
   def test_pluck_not_auto_table_name_prefix_if_column_joined
-    Company.create!(:name => "test", :contracts => [Contract.new(:developer_id => 7)])
+    Company.create!(name: "test", contracts: [Contract.new(developer_id: 7)])
     assert_equal [7], Company.joins(:contracts).pluck(:developer_id)
   end
 
   def test_pluck_with_selection_clause
-    assert_equal [50, 53, 55, 60], Account.pluck('DISTINCT credit_limit').sort
-    assert_equal [50, 53, 55, 60], Account.pluck('DISTINCT accounts.credit_limit').sort
-    assert_equal [50, 53, 55, 60], Account.pluck('DISTINCT(credit_limit)').sort
+    assert_equal [50, 53, 55, 60], Account.pluck(Arel.sql("DISTINCT credit_limit")).sort
+    assert_equal [50, 53, 55, 60], Account.pluck(Arel.sql("DISTINCT accounts.credit_limit")).sort
+    assert_equal [50, 53, 55, 60], Account.pluck(Arel.sql("DISTINCT(credit_limit)")).sort
 
     # MySQL returns "SUM(DISTINCT(credit_limit))" as the column name unless
     # an alias is provided.  Without the alias, the column cannot be found
     # and properly typecast.
-    assert_equal [50 + 53 + 55 + 60], Account.pluck('SUM(DISTINCT(credit_limit)) as credit_limit')
+    assert_equal [50 + 53 + 55 + 60], Account.pluck(Arel.sql("SUM(DISTINCT(credit_limit)) as credit_limit"))
   end
 
   def test_plucks_with_ids
@@ -642,11 +685,11 @@ class CalculationsTest < ActiveRecord::TestCase
 
   def test_pluck_with_includes_limit_and_empty_result
     assert_equal [], Topic.includes(:replies).limit(0).pluck(:id)
-    assert_equal [], Topic.includes(:replies).limit(1).where('0 = 1').pluck(:id)
+    assert_equal [], Topic.includes(:replies).limit(1).where("0 = 1").pluck(:id)
   end
 
   def test_pluck_not_auto_table_name_prefix_if_column_included
-    Company.create!(:name => "test", :contracts => [Contract.new(:developer_id => 7)])
+    Company.create!(name: "test", contracts: [Contract.new(developer_id: 7)])
     ids = Company.includes(:contracts).pluck(:developer_id)
     assert_equal Company.count, ids.length
     assert_equal [7], ids.compact
@@ -667,12 +710,12 @@ class CalculationsTest < ActiveRecord::TestCase
 
   def test_pluck_with_multiple_columns_and_selection_clause
     assert_equal [[1, 50], [2, 50], [3, 50], [4, 60], [5, 55], [6, 53]],
-      Account.pluck('id, credit_limit')
+      Account.pluck("id, credit_limit")
   end
 
   def test_pluck_with_multiple_columns_and_includes
-    Company.create!(:name => "test", :contracts => [Contract.new(:developer_id => 7)])
-    companies_and_developers = Company.order('companies.id').includes(:contracts).pluck(:name, :developer_id)
+    Company.create!(name: "test", contracts: [Contract.new(developer_id: 7)])
+    companies_and_developers = Company.order("companies.id").includes(:contracts).pluck(:name, :developer_id)
 
     assert_equal Company.count, companies_and_developers.length
     assert_equal ["37signals", nil], companies_and_developers.first
@@ -680,21 +723,21 @@ class CalculationsTest < ActiveRecord::TestCase
   end
 
   def test_pluck_with_reserved_words
-    Possession.create!(:where => "Over There")
+    Possession.create!(where: "Over There")
 
     assert_equal ["Over There"], Possession.pluck(:where)
   end
 
   def test_pluck_replaces_select_clause
     taks_relation = Topic.select(:approved, :id).order(:id)
-    assert_equal [1,2,3,4,5], taks_relation.pluck(:id)
+    assert_equal [1, 2, 3, 4, 5], taks_relation.pluck(:id)
     assert_equal [false, true, true, true, true], taks_relation.pluck(:approved)
   end
 
   def test_pluck_columns_with_same_name
     expected = [["The First Topic", "The Second Topic of the day"], ["The Third Topic of the day", "The Fourth Topic of the day"]]
     actual = Topic.joins(:replies)
-      .pluck('topics.title', 'replies_topics.title')
+      .pluck("topics.title", "replies_topics.title")
     assert_equal expected, actual
   end
 
@@ -713,23 +756,29 @@ class CalculationsTest < ActiveRecord::TestCase
   end
 
   def test_pluck_loaded_relation
+    Company.attribute_names # Load schema information so we don't query below
     companies = Company.order(:id).limit(3).load
+
     assert_no_queries do
-      assert_equal ['37signals', 'Summit', 'Microsoft'], companies.pluck(:name)
+      assert_equal ["37signals", "Summit", "Microsoft"], companies.pluck(:name)
     end
   end
 
   def test_pluck_loaded_relation_multiple_columns
+    Company.attribute_names # Load schema information so we don't query below
     companies = Company.order(:id).limit(3).load
+
     assert_no_queries do
-      assert_equal [[1, '37signals'], [2, 'Summit'], [3, 'Microsoft']], companies.pluck(:id, :name)
+      assert_equal [[1, "37signals"], [2, "Summit"], [3, "Microsoft"]], companies.pluck(:id, :name)
     end
   end
 
   def test_pluck_loaded_relation_sql_fragment
+    Company.attribute_names # Load schema information so we don't query below
     companies = Company.order(:name).limit(3).load
+
     assert_queries 1 do
-      assert_equal ['37signals', 'Apex', 'Ex Nihilo'], companies.pluck('DISTINCT name')
+      assert_equal ["37signals", "Apex", "Ex Nihilo"], companies.pluck(Arel.sql("DISTINCT name"))
     end
   end
 
@@ -747,7 +796,7 @@ class CalculationsTest < ActiveRecord::TestCase
 
   def test_should_reference_correct_aliases_while_joining_tables_of_has_many_through_association
     assert_nothing_raised do
-      developer = Developer.create!(name: 'developer')
+      developer = Developer.create!(name: "developer")
       developer.ratings.includes(comment: :post).where(posts: { id: 1 }).count
     end
   end
@@ -782,7 +831,7 @@ class CalculationsTest < ActiveRecord::TestCase
       end
     end
 
-    params = protected_params.new(credit_limit: '50')
+    params = protected_params.new(credit_limit: "50")
 
     assert_raises(ActiveModel::ForbiddenAttributesError) do
       Account.group(:id).having(params)
@@ -793,4 +842,62 @@ class CalculationsTest < ActiveRecord::TestCase
     assert_equal 50, result[1].credit_limit
     assert_equal 50, result[2].credit_limit
   end
+
+  def test_group_by_attribute_with_custom_type
+    assert_equal({ "proposed" => 2, "published" => 2 }, Book.group(:status).count)
+  end
+
+  def test_deprecate_count_with_block_and_column_name
+    assert_deprecated do
+      assert_equal 6, Account.count(:firm_id) { true }
+    end
+  end
+
+  def test_deprecate_sum_with_block_and_column_name
+    assert_deprecated do
+      assert_equal 6, Account.sum(:firm_id) { 1 }
+    end
+  end
+
+  test "#skip_query_cache! for #pluck" do
+    Account.cache do
+      assert_queries(1) do
+        Account.pluck(:credit_limit)
+        Account.pluck(:credit_limit)
+      end
+
+      assert_queries(2) do
+        Account.all.skip_query_cache!.pluck(:credit_limit)
+        Account.all.skip_query_cache!.pluck(:credit_limit)
+      end
+    end
+  end
+
+  test "#skip_query_cache! for a simple calculation" do
+    Account.cache do
+      assert_queries(1) do
+        Account.calculate(:sum, :credit_limit)
+        Account.calculate(:sum, :credit_limit)
+      end
+
+      assert_queries(2) do
+        Account.all.skip_query_cache!.calculate(:sum, :credit_limit)
+        Account.all.skip_query_cache!.calculate(:sum, :credit_limit)
+      end
+    end
+  end
+
+  test "#skip_query_cache! for a grouped calculation" do
+    Account.cache do
+      assert_queries(1) do
+        Account.group(:firm_id).calculate(:sum, :credit_limit)
+        Account.group(:firm_id).calculate(:sum, :credit_limit)
+      end
+
+      assert_queries(2) do
+        Account.all.skip_query_cache!.group(:firm_id).calculate(:sum, :credit_limit)
+        Account.all.skip_query_cache!.group(:firm_id).calculate(:sum, :credit_limit)
+      end
+    end
+  end
 end
diff --git a/activerecord/test/cases/callbacks_test.rb b/activerecord/test/cases/callbacks_test.rb
index 4f70ae3a1d..55c7475f46 100644
--- a/activerecord/test/cases/callbacks_test.rb
+++ b/activerecord/test/cases/callbacks_test.rb
@@ -1,22 +1,20 @@
+# frozen_string_literal: true
+
 require "cases/helper"
-require 'models/developer'
-require 'models/computer'
+require "models/developer"
+require "models/computer"
 
 class CallbackDeveloper < ActiveRecord::Base
-  self.table_name = 'developers'
+  self.table_name = "developers"
 
   class << self
-    def callback_string(callback_method)
-      "history << [#{callback_method.to_sym.inspect}, :string]"
-    end
-
     def callback_proc(callback_method)
       Proc.new { |model| model.history << [callback_method, :proc] }
     end
 
     def define_callback_method(callback_method)
       define_method(callback_method) do
-        self.history << [callback_method, :method]
+        history << [callback_method, :method]
       end
       send(callback_method, :"#{callback_method}")
     end
@@ -31,9 +29,8 @@ class CallbackDeveloper < ActiveRecord::Base
   end
 
   ActiveRecord::Callbacks::CALLBACKS.each do |callback_method|
-    next if callback_method.to_s =~ /^around_/
+    next if callback_method.to_s.start_with?("around_")
     define_callback_method(callback_method)
-    ActiveSupport::Deprecation.silence { send(callback_method, callback_string(callback_method)) }
     send(callback_method, callback_proc(callback_method))
     send(callback_method, callback_object(callback_method))
     send(callback_method) { |model| model.history << [callback_method, :block] }
@@ -44,30 +41,24 @@ class CallbackDeveloper < ActiveRecord::Base
   end
 end
 
-class CallbackDeveloperWithFalseValidation < CallbackDeveloper
-  before_validation proc { |model| model.history << [:before_validation, :returning_false]; false }
-  before_validation proc { |model| model.history << [:before_validation, :should_never_get_here] }
-end
-
 class CallbackDeveloperWithHaltedValidation < CallbackDeveloper
   before_validation proc { |model| model.history << [:before_validation, :throwing_abort]; throw(:abort) }
   before_validation proc { |model| model.history << [:before_validation, :should_never_get_here] }
 end
 
 class ParentDeveloper < ActiveRecord::Base
-  self.table_name = 'developers'
+  self.table_name = "developers"
   attr_accessor :after_save_called
-  before_validation {|record| record.after_save_called = true}
+  before_validation { |record| record.after_save_called = true }
 end
 
 class ChildDeveloper < ParentDeveloper
-
 end
 
 class ImmutableDeveloper < ActiveRecord::Base
-  self.table_name = 'developers'
+  self.table_name = "developers"
 
-  validates_inclusion_of :salary, :in => 50000..200000
+  validates_inclusion_of :salary, in: 50000..200000
 
   before_save :cancel
   before_destroy :cancel
@@ -79,7 +70,7 @@ class ImmutableDeveloper < ActiveRecord::Base
 end
 
 class DeveloperWithCanceledCallbacks < ActiveRecord::Base
-  self.table_name = 'developers'
+  self.table_name = "developers"
 
   validates_inclusion_of :salary, in: 50000..200000
 
@@ -93,19 +84,19 @@ class DeveloperWithCanceledCallbacks < ActiveRecord::Base
 end
 
 class OnCallbacksDeveloper < ActiveRecord::Base
-  self.table_name = 'developers'
+  self.table_name = "developers"
 
   before_validation { history << :before_validation }
-  before_validation(:on => :create){ history << :before_validation_on_create }
-  before_validation(:on => :update){ history << :before_validation_on_update }
+  before_validation(on: :create) { history << :before_validation_on_create }
+  before_validation(on: :update) { history << :before_validation_on_update }
 
   validate do
     history << :validate
   end
 
   after_validation { history << :after_validation }
-  after_validation(:on => :create){ history << :after_validation_on_create }
-  after_validation(:on => :update){ history << :after_validation_on_update }
+  after_validation(on: :create) { history << :after_validation_on_create }
+  after_validation(on: :update) { history << :after_validation_on_update }
 
   def history
     @history ||= []
@@ -113,24 +104,24 @@ class OnCallbacksDeveloper < ActiveRecord::Base
 end
 
 class ContextualCallbacksDeveloper < ActiveRecord::Base
-  self.table_name = 'developers'
+  self.table_name = "developers"
 
   before_validation { history << :before_validation }
-  before_validation :before_validation_on_create_and_update, :on => [ :create, :update ]
+  before_validation :before_validation_on_create_and_update, on: [ :create, :update ]
 
   validate do
     history << :validate
   end
 
   after_validation { history << :after_validation }
-  after_validation :after_validation_on_create_and_update, :on => [ :create, :update ]
+  after_validation :after_validation_on_create_and_update, on: [ :create, :update ]
 
   def before_validation_on_create_and_update
-    history << "before_validation_on_#{self.validation_context}".to_sym
+    history << "before_validation_on_#{validation_context}".to_sym
   end
 
   def after_validation_on_create_and_update
-    history << "after_validation_on_#{self.validation_context}".to_sym
+    history << "after_validation_on_#{validation_context}".to_sym
   end
 
   def history
@@ -138,25 +129,8 @@ class ContextualCallbacksDeveloper < ActiveRecord::Base
   end
 end
 
-class CallbackCancellationDeveloper < ActiveRecord::Base
-  self.table_name = 'developers'
-
-  attr_reader   :after_save_called, :after_create_called, :after_update_called, :after_destroy_called
-  attr_accessor :cancel_before_save, :cancel_before_create, :cancel_before_update, :cancel_before_destroy
-
-  before_save    {defined?(@cancel_before_save) ? !@cancel_before_save : false}
-  before_create  { !@cancel_before_create  }
-  before_update  { !@cancel_before_update  }
-  before_destroy { !@cancel_before_destroy }
-
-  after_save    { @after_save_called    = true }
-  after_update  { @after_update_called  = true }
-  after_create  { @after_create_called  = true }
-  after_destroy { @after_destroy_called = true }
-end
-
 class CallbackHaltedDeveloper < ActiveRecord::Base
-  self.table_name = 'developers'
+  self.table_name = "developers"
 
   attr_reader   :after_save_called, :after_create_called, :after_update_called, :after_destroy_called
   attr_accessor :cancel_before_save, :cancel_before_create, :cancel_before_update, :cancel_before_destroy
@@ -179,7 +153,6 @@ class CallbacksTest < ActiveRecord::TestCase
     david = CallbackDeveloper.new
     assert_equal [
       [ :after_initialize,            :method ],
-      [ :after_initialize,            :string ],
       [ :after_initialize,            :proc   ],
       [ :after_initialize,            :object ],
       [ :after_initialize,            :block  ],
@@ -190,12 +163,10 @@ class CallbacksTest < ActiveRecord::TestCase
     david = CallbackDeveloper.find(1)
     assert_equal [
       [ :after_find,            :method ],
-      [ :after_find,            :string ],
       [ :after_find,            :proc   ],
       [ :after_find,            :object ],
       [ :after_find,            :block  ],
       [ :after_initialize,            :method ],
-      [ :after_initialize,            :string ],
       [ :after_initialize,            :proc   ],
       [ :after_initialize,            :object ],
       [ :after_initialize,            :block  ],
@@ -207,17 +178,14 @@ class CallbacksTest < ActiveRecord::TestCase
     david.valid?
     assert_equal [
       [ :after_initialize,            :method ],
-      [ :after_initialize,            :string ],
       [ :after_initialize,            :proc   ],
       [ :after_initialize,            :object ],
       [ :after_initialize,            :block  ],
       [ :before_validation,           :method ],
-      [ :before_validation,           :string ],
       [ :before_validation,           :proc   ],
       [ :before_validation,           :object ],
       [ :before_validation,           :block  ],
       [ :after_validation,            :method ],
-      [ :after_validation,            :string ],
       [ :after_validation,            :proc   ],
       [ :after_validation,            :object ],
       [ :after_validation,            :block  ],
@@ -229,22 +197,18 @@ class CallbacksTest < ActiveRecord::TestCase
     david.valid?
     assert_equal [
       [ :after_find,            :method ],
-      [ :after_find,            :string ],
       [ :after_find,            :proc   ],
       [ :after_find,            :object ],
       [ :after_find,            :block  ],
       [ :after_initialize,            :method ],
-      [ :after_initialize,            :string ],
       [ :after_initialize,            :proc   ],
       [ :after_initialize,            :object ],
       [ :after_initialize,            :block  ],
       [ :before_validation,           :method ],
-      [ :before_validation,           :string ],
       [ :before_validation,           :proc   ],
       [ :before_validation,           :object ],
       [ :before_validation,           :block  ],
       [ :after_validation,            :method ],
-      [ :after_validation,            :string ],
       [ :after_validation,            :proc   ],
       [ :after_validation,            :object ],
       [ :after_validation,            :block  ],
@@ -252,53 +216,45 @@ class CallbacksTest < ActiveRecord::TestCase
   end
 
   def test_create
-    david = CallbackDeveloper.create('name' => 'David', 'salary' => 1000000)
+    david = CallbackDeveloper.create("name" => "David", "salary" => 1000000)
     assert_equal [
       [ :after_initialize,            :method ],
-      [ :after_initialize,            :string ],
       [ :after_initialize,            :proc   ],
       [ :after_initialize,            :object ],
       [ :after_initialize,            :block  ],
       [ :before_validation,           :method ],
-      [ :before_validation,           :string ],
       [ :before_validation,           :proc   ],
       [ :before_validation,           :object ],
       [ :before_validation,           :block  ],
       [ :after_validation,            :method ],
-      [ :after_validation,            :string ],
       [ :after_validation,            :proc   ],
       [ :after_validation,            :object ],
       [ :after_validation,            :block  ],
       [ :before_save,                 :method ],
-      [ :before_save,                 :string ],
       [ :before_save,                 :proc   ],
       [ :before_save,                 :object ],
       [ :before_save,                 :block  ],
       [ :before_create,               :method ],
-      [ :before_create,               :string ],
       [ :before_create,               :proc   ],
       [ :before_create,               :object ],
       [ :before_create,               :block  ],
       [ :after_create,                :method ],
-      [ :after_create,                :string ],
       [ :after_create,                :proc   ],
       [ :after_create,                :object ],
       [ :after_create,                :block  ],
       [ :after_save,                  :method ],
-      [ :after_save,                  :string ],
       [ :after_save,                  :proc   ],
       [ :after_save,                  :object ],
       [ :after_save,                  :block  ],
       [ :after_commit,                :block  ],
       [ :after_commit,                :object ],
       [ :after_commit,                :proc   ],
-      [ :after_commit,                :string ],
       [ :after_commit,                :method ]
     ], david.history
   end
 
   def test_validate_on_create
-    david = OnCallbacksDeveloper.create('name' => 'David', 'salary' => 1000000)
+    david = OnCallbacksDeveloper.create("name" => "David", "salary" => 1000000)
     assert_equal [
       :before_validation,
       :before_validation_on_create,
@@ -309,7 +265,7 @@ class CallbacksTest < ActiveRecord::TestCase
   end
 
   def test_validate_on_contextual_create
-    david = ContextualCallbacksDeveloper.create('name' => 'David', 'salary' => 1000000)
+    david = ContextualCallbacksDeveloper.create("name" => "David", "salary" => 1000000)
     assert_equal [
       :before_validation,
       :before_validation_on_create,
@@ -324,49 +280,40 @@ class CallbacksTest < ActiveRecord::TestCase
     david.save
     assert_equal [
       [ :after_find,            :method ],
-      [ :after_find,            :string ],
       [ :after_find,            :proc   ],
       [ :after_find,            :object ],
       [ :after_find,            :block  ],
       [ :after_initialize,            :method ],
-      [ :after_initialize,            :string ],
       [ :after_initialize,            :proc   ],
       [ :after_initialize,            :object ],
       [ :after_initialize,            :block  ],
       [ :before_validation,           :method ],
-      [ :before_validation,           :string ],
       [ :before_validation,           :proc   ],
       [ :before_validation,           :object ],
       [ :before_validation,           :block  ],
       [ :after_validation,            :method ],
-      [ :after_validation,            :string ],
       [ :after_validation,            :proc   ],
       [ :after_validation,            :object ],
       [ :after_validation,            :block  ],
       [ :before_save,                 :method ],
-      [ :before_save,                 :string ],
       [ :before_save,                 :proc   ],
       [ :before_save,                 :object ],
       [ :before_save,                 :block  ],
       [ :before_update,               :method ],
-      [ :before_update,               :string ],
       [ :before_update,               :proc   ],
       [ :before_update,               :object ],
       [ :before_update,               :block  ],
       [ :after_update,                :method ],
-      [ :after_update,                :string ],
       [ :after_update,                :proc   ],
       [ :after_update,                :object ],
       [ :after_update,                :block  ],
       [ :after_save,                  :method ],
-      [ :after_save,                  :string ],
       [ :after_save,                  :proc   ],
       [ :after_save,                  :object ],
       [ :after_save,                  :block  ],
       [ :after_commit,                :block  ],
       [ :after_commit,                :object ],
       [ :after_commit,                :proc   ],
-      [ :after_commit,                :string ],
       [ :after_commit,                :method ]
     ], david.history
   end
@@ -400,29 +347,24 @@ class CallbacksTest < ActiveRecord::TestCase
     david.destroy
     assert_equal [
       [ :after_find,            :method ],
-      [ :after_find,            :string ],
       [ :after_find,            :proc   ],
       [ :after_find,            :object ],
       [ :after_find,            :block  ],
       [ :after_initialize,            :method ],
-      [ :after_initialize,            :string ],
       [ :after_initialize,            :proc   ],
       [ :after_initialize,            :object ],
       [ :after_initialize,            :block  ],
       [ :before_destroy,              :method ],
-      [ :before_destroy,              :string ],
       [ :before_destroy,              :proc   ],
       [ :before_destroy,              :object ],
       [ :before_destroy,              :block  ],
       [ :after_destroy,               :method ],
-      [ :after_destroy,               :string ],
       [ :after_destroy,               :proc   ],
       [ :after_destroy,               :object ],
       [ :after_destroy,               :block  ],
       [ :after_commit,                :block  ],
       [ :after_commit,                :object ],
       [ :after_commit,                :proc   ],
-      [ :after_commit,                :string ],
       [ :after_commit,                :method ]
     ], david.history
   end
@@ -432,82 +374,16 @@ class CallbacksTest < ActiveRecord::TestCase
     CallbackDeveloper.delete(david.id)
     assert_equal [
       [ :after_find,            :method ],
-      [ :after_find,            :string ],
       [ :after_find,            :proc   ],
       [ :after_find,            :object ],
       [ :after_find,            :block  ],
       [ :after_initialize,            :method ],
-      [ :after_initialize,            :string ],
       [ :after_initialize,            :proc   ],
       [ :after_initialize,            :object ],
       [ :after_initialize,            :block  ],
     ], david.history
   end
 
-  def test_deprecated_before_save_returning_false
-    david = ImmutableDeveloper.find(1)
-    assert_deprecated do
-      assert david.valid?
-      assert !david.save
-      exc = assert_raise(ActiveRecord::RecordNotSaved) { david.save! }
-      assert_equal exc.record, david
-      assert_equal "Failed to save the record", exc.message
-    end
-
-    david = ImmutableDeveloper.find(1)
-    david.salary = 10_000_000
-    assert !david.valid?
-    assert !david.save
-    assert_raise(ActiveRecord::RecordInvalid) { david.save! }
-
-    someone = CallbackCancellationDeveloper.find(1)
-    someone.cancel_before_save = true
-    assert_deprecated do
-      assert someone.valid?
-      assert !someone.save
-    end
-    assert_save_callbacks_not_called(someone)
-  end
-
-  def test_deprecated_before_create_returning_false
-    someone = CallbackCancellationDeveloper.new
-    someone.cancel_before_create = true
-    assert_deprecated do
-      assert someone.valid?
-      assert !someone.save
-    end
-    assert_save_callbacks_not_called(someone)
-  end
-
-  def test_deprecated_before_update_returning_false
-    someone = CallbackCancellationDeveloper.find(1)
-    someone.cancel_before_update = true
-    assert_deprecated do
-      assert someone.valid?
-      assert !someone.save
-    end
-    assert_save_callbacks_not_called(someone)
-  end
-
-  def test_deprecated_before_destroy_returning_false
-    david = ImmutableDeveloper.find(1)
-    assert_deprecated do
-      assert !david.destroy
-      exc = assert_raise(ActiveRecord::RecordNotDestroyed) { david.destroy! }
-      assert_equal exc.record, david
-      assert_equal "Failed to destroy the record", exc.message
-    end
-    assert_not_nil ImmutableDeveloper.find_by_id(1)
-
-    someone = CallbackCancellationDeveloper.find(1)
-    someone.cancel_before_destroy = true
-    assert_deprecated do
-      assert !someone.destroy
-      assert_raise(ActiveRecord::RecordNotDestroyed) { someone.destroy! }
-    end
-    assert !someone.after_destroy_called
-  end
-
   def assert_save_callbacks_not_called(someone)
     assert !someone.after_save_called
     assert !someone.after_create_called
@@ -528,7 +404,7 @@ class CallbacksTest < ActiveRecord::TestCase
     assert david.valid?
     assert !david.save
     exc = assert_raise(ActiveRecord::RecordNotSaved) { david.save! }
-    assert_equal exc.record, david
+    assert_equal david, exc.record
 
     david = DeveloperWithCanceledCallbacks.find(1)
     david.salary = 10_000_000
@@ -555,7 +431,7 @@ class CallbacksTest < ActiveRecord::TestCase
     david = DeveloperWithCanceledCallbacks.find(1)
     assert !david.destroy
     exc = assert_raise(ActiveRecord::RecordNotDestroyed) { david.destroy! }
-    assert_equal exc.record, david
+    assert_equal david, exc.record
     assert_not_nil ImmutableDeveloper.find_by_id(1)
 
     someone = CallbackHaltedDeveloper.find(1)
@@ -565,50 +441,19 @@ class CallbacksTest < ActiveRecord::TestCase
     assert !someone.after_destroy_called
   end
 
-  def test_callback_returning_false
-    david = CallbackDeveloperWithFalseValidation.find(1)
-    assert_deprecated { david.save }
-    assert_equal [
-      [ :after_find,            :method ],
-      [ :after_find,            :string ],
-      [ :after_find,            :proc   ],
-      [ :after_find,            :object ],
-      [ :after_find,            :block  ],
-      [ :after_initialize,            :method ],
-      [ :after_initialize,            :string ],
-      [ :after_initialize,            :proc   ],
-      [ :after_initialize,            :object ],
-      [ :after_initialize,            :block  ],
-      [ :before_validation,           :method ],
-      [ :before_validation,           :string ],
-      [ :before_validation,           :proc   ],
-      [ :before_validation,           :object ],
-      [ :before_validation,           :block  ],
-      [ :before_validation, :returning_false  ],
-      [ :after_rollback, :block  ],
-      [ :after_rollback, :object ],
-      [ :after_rollback, :proc   ],
-      [ :after_rollback, :string ],
-      [ :after_rollback, :method ],
-    ], david.history
-  end
-
   def test_callback_throwing_abort
     david = CallbackDeveloperWithHaltedValidation.find(1)
     david.save
     assert_equal [
       [ :after_find,        :method ],
-      [ :after_find,        :string ],
       [ :after_find,        :proc   ],
       [ :after_find,        :object ],
       [ :after_find,        :block  ],
       [ :after_initialize,  :method ],
-      [ :after_initialize,  :string ],
       [ :after_initialize,  :proc   ],
       [ :after_initialize,  :object ],
       [ :after_initialize,  :block  ],
       [ :before_validation, :method ],
-      [ :before_validation, :string ],
       [ :before_validation, :proc   ],
       [ :before_validation, :object ],
       [ :before_validation, :block  ],
@@ -616,7 +461,6 @@ class CallbacksTest < ActiveRecord::TestCase
       [ :after_rollback,    :block  ],
       [ :after_rollback,    :object ],
       [ :after_rollback,    :proc   ],
-      [ :after_rollback,    :string ],
       [ :after_rollback,    :method ],
     ], david.history
   end
@@ -632,5 +476,4 @@ class CallbacksTest < ActiveRecord::TestCase
     child.save
     assert child.after_save_called
   end
-
 end
diff --git a/activerecord/test/cases/clone_test.rb b/activerecord/test/cases/clone_test.rb
index 5e43082c33..3187e6aed5 100644
--- a/activerecord/test/cases/clone_test.rb
+++ b/activerecord/test/cases/clone_test.rb
@@ -1,5 +1,7 @@
+# frozen_string_literal: true
+
 require "cases/helper"
-require 'models/topic'
+require "models/topic"
 
 module ActiveRecord
   class CloneTest < ActiveRecord::TestCase
@@ -8,9 +10,9 @@ module ActiveRecord
     def test_persisted
       topic = Topic.first
       cloned = topic.clone
-      assert topic.persisted?, 'topic persisted'
-      assert cloned.persisted?, 'topic persisted'
-      assert !cloned.new_record?, 'topic is not new'
+      assert topic.persisted?, "topic persisted"
+      assert cloned.persisted?, "topic persisted"
+      assert !cloned.new_record?, "topic is not new"
     end
 
     def test_stays_frozen
@@ -18,16 +20,16 @@ module ActiveRecord
       topic.freeze
 
       cloned = topic.clone
-      assert cloned.persisted?, 'topic persisted'
-      assert !cloned.new_record?, 'topic is not new'
-      assert cloned.frozen?, 'topic should be frozen'
+      assert cloned.persisted?, "topic persisted"
+      assert !cloned.new_record?, "topic is not new"
+      assert cloned.frozen?, "topic should be frozen"
     end
 
     def test_shallow
       topic = Topic.first
       cloned = topic.clone
-      topic.author_name = 'Aaron'
-      assert_equal 'Aaron', cloned.author_name
+      topic.author_name = "Aaron"
+      assert_equal "Aaron", cloned.author_name
     end
 
     def test_freezing_a_cloned_model_does_not_freeze_clone
diff --git a/activerecord/test/cases/coders/json_test.rb b/activerecord/test/cases/coders/json_test.rb
index d22d93d129..e40d576b39 100644
--- a/activerecord/test/cases/coders/json_test.rb
+++ b/activerecord/test/cases/coders/json_test.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require "cases/helper"
 
 module ActiveRecord
diff --git a/activerecord/test/cases/coders/yaml_column_test.rb b/activerecord/test/cases/coders/yaml_column_test.rb
index b72c54f97b..4a5559c62f 100644
--- a/activerecord/test/cases/coders/yaml_column_test.rb
+++ b/activerecord/test/cases/coders/yaml_column_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 
 require "cases/helper"
 
@@ -5,54 +6,56 @@ module ActiveRecord
   module Coders
     class YAMLColumnTest < ActiveRecord::TestCase
       def test_initialize_takes_class
-        coder = YAMLColumn.new(Object)
+        coder = YAMLColumn.new("attr_name", Object)
         assert_equal Object, coder.object_class
       end
 
       def test_type_mismatch_on_different_classes_on_dump
-        coder = YAMLColumn.new(Array)
-        assert_raises(SerializationTypeMismatch) do
+        coder = YAMLColumn.new("tags", Array)
+        error = assert_raises(SerializationTypeMismatch) do
           coder.dump("a")
         end
+        assert_equal %{can't dump `tags`: was supposed to be a Array, but was a String. -- "a"}, error.to_s
       end
 
       def test_type_mismatch_on_different_classes
-        coder = YAMLColumn.new(Array)
-        assert_raises(SerializationTypeMismatch) do
+        coder = YAMLColumn.new("tags", Array)
+        error = assert_raises(SerializationTypeMismatch) do
           coder.load "--- foo"
         end
+        assert_equal %{can't load `tags`: was supposed to be a Array, but was a String. -- "foo"}, error.to_s
       end
 
       def test_nil_is_ok
-        coder = YAMLColumn.new
+        coder = YAMLColumn.new("attr_name")
         assert_nil coder.load "--- "
       end
 
       def test_returns_new_with_different_class
-        coder = YAMLColumn.new SerializationTypeMismatch
+        coder = YAMLColumn.new("attr_name", SerializationTypeMismatch)
         assert_equal SerializationTypeMismatch, coder.load("--- ").class
       end
 
       def test_returns_string_unless_starts_with_dash
-        coder = YAMLColumn.new
-        assert_equal 'foo', coder.load("foo")
+        coder = YAMLColumn.new("attr_name")
+        assert_equal "foo", coder.load("foo")
       end
 
       def test_load_handles_other_classes
-        coder = YAMLColumn.new
+        coder = YAMLColumn.new("attr_name")
         assert_equal [], coder.load([])
       end
 
       def test_load_doesnt_swallow_yaml_exceptions
-        coder = YAMLColumn.new
-        bad_yaml = '--- {'
+        coder = YAMLColumn.new("attr_name")
+        bad_yaml = "--- {"
         assert_raises(Psych::SyntaxError) do
           coder.load(bad_yaml)
         end
       end
 
       def test_load_doesnt_handle_undefined_class_or_module
-        coder = YAMLColumn.new
+        coder = YAMLColumn.new("attr_name")
         missing_class_yaml = '--- !ruby/object:DoesNotExistAndShouldntEver {}\n'
         assert_raises(ArgumentError) do
           coder.load(missing_class_yaml)
diff --git a/activerecord/test/cases/collection_cache_key_test.rb b/activerecord/test/cases/collection_cache_key_test.rb
index a2874438c1..cfe95b2360 100644
--- a/activerecord/test/cases/collection_cache_key_test.rb
+++ b/activerecord/test/cases/collection_cache_key_test.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require "cases/helper"
 require "models/computer"
 require "models/developer"
@@ -11,44 +13,98 @@ module ActiveRecord
     fixtures :developers, :projects, :developers_projects, :topics, :comments, :posts
 
     test "collection_cache_key on model" do
-      assert_match(/\Adevelopers\/query-(\h+)-(\d+)-(\d+)\Z/, Developer.collection_cache_key)
+      assert_match(/\Adevelopers\/query-(\h+)-(\d+)-(\d+)\z/, Developer.collection_cache_key)
     end
 
     test "cache_key for relation" do
-      developers = Developer.where(name: "David")
-      last_developer_timestamp = developers.order(updated_at: :desc).first.updated_at
+      developers = Developer.where(salary: 100000).order(updated_at: :desc)
+      last_developer_timestamp = developers.first.updated_at
+
+      assert_match(/\Adevelopers\/query-(\h+)-(\d+)-(\d+)\z/, developers.cache_key)
+
+      /\Adevelopers\/query-(\h+)-(\d+)-(\d+)\z/ =~ developers.cache_key
+
+      assert_equal ActiveSupport::Digest.hexdigest(developers.to_sql), $1
+      assert_equal developers.count.to_s, $2
+      assert_equal last_developer_timestamp.to_s(ActiveRecord::Base.cache_timestamp_format), $3
+    end
+
+    test "cache_key for relation with limit" do
+      developers = Developer.where(salary: 100000).order(updated_at: :desc).limit(5)
+      last_developer_timestamp = developers.first.updated_at
 
-      assert_match(/\Adevelopers\/query-(\h+)-(\d+)-(\d+)\Z/, developers.cache_key)
+      assert_match(/\Adevelopers\/query-(\h+)-(\d+)-(\d+)\z/, developers.cache_key)
 
-      /\Adevelopers\/query-(\h+)-(\d+)-(\d+)\Z/ =~ developers.cache_key
+      /\Adevelopers\/query-(\h+)-(\d+)-(\d+)\z/ =~ developers.cache_key
 
-      assert_equal Digest::MD5.hexdigest(developers.to_sql), $1
+      assert_equal ActiveSupport::Digest.hexdigest(developers.to_sql), $1
       assert_equal developers.count.to_s, $2
       assert_equal last_developer_timestamp.to_s(ActiveRecord::Base.cache_timestamp_format), $3
     end
 
+    test "cache_key for loaded relation" do
+      developers = Developer.where(salary: 100000).order(updated_at: :desc).limit(5).load
+      last_developer_timestamp = developers.first.updated_at
+
+      assert_match(/\Adevelopers\/query-(\h+)-(\d+)-(\d+)\z/, developers.cache_key)
+
+      /\Adevelopers\/query-(\h+)-(\d+)-(\d+)\z/ =~ developers.cache_key
+
+      assert_equal ActiveSupport::Digest.hexdigest(developers.to_sql), $1
+      assert_equal developers.count.to_s, $2
+      assert_equal last_developer_timestamp.to_s(ActiveRecord::Base.cache_timestamp_format), $3
+    end
+
+    test "cache_key for relation with table alias" do
+      table_alias = Developer.arel_table.alias("omg_developers")
+      table_metadata = ActiveRecord::TableMetadata.new(Developer, table_alias)
+      predicate_builder = ActiveRecord::PredicateBuilder.new(table_metadata)
+
+      developers = ActiveRecord::Relation.create(Developer, table_alias, predicate_builder)
+      developers = developers.where(salary: 100000).order(updated_at: :desc)
+      last_developer_timestamp = developers.first.updated_at
+
+      assert_match(/\Adevelopers\/query-(\h+)-(\d+)-(\d+)\z/, developers.cache_key)
+
+      /\Adevelopers\/query-(\h+)-(\d+)-(\d+)\z/ =~ developers.cache_key
+
+      assert_equal ActiveSupport::Digest.hexdigest(developers.to_sql), $1
+      assert_equal developers.count.to_s, $2
+      assert_equal last_developer_timestamp.to_s(ActiveRecord::Base.cache_timestamp_format), $3
+    end
+
+    test "cache_key for relation with includes" do
+      comments = Comment.includes(:post).where("posts.type": "Post")
+      assert_match(/\Acomments\/query-(\h+)-(\d+)-(\d+)\z/, comments.cache_key)
+    end
+
+    test "cache_key for loaded relation with includes" do
+      comments = Comment.includes(:post).where("posts.type": "Post").load
+      assert_match(/\Acomments\/query-(\h+)-(\d+)-(\d+)\z/, comments.cache_key)
+    end
+
     test "it triggers at most one query" do
-      developers =  Developer.where(name: "David")
+      developers = Developer.where(name: "David")
 
       assert_queries(1) { developers.cache_key }
       assert_queries(0) { developers.cache_key }
     end
 
     test "it doesn't trigger any query if the relation is already loaded" do
-      developers =  Developer.where(name: "David").load
+      developers = Developer.where(name: "David").load
       assert_queries(0) { developers.cache_key }
     end
 
     test "relation cache_key changes when the sql query changes" do
       developers = Developer.where(name: "David")
-      other_relation =  Developer.where(name: "David").where("1 = 1")
+      other_relation = Developer.where(name: "David").where("1 = 1")
 
       assert_not_equal developers.cache_key, other_relation.cache_key
     end
 
     test "cache_key for empty relation" do
       developers = Developer.where(name: "Non Existent Developer")
-      assert_match(/\Adevelopers\/query-(\h+)-0\Z/, developers.cache_key)
+      assert_match(/\Adevelopers\/query-(\h+)-0\z/, developers.cache_key)
     end
 
     test "cache_key with custom timestamp column" do
@@ -64,7 +120,7 @@ module ActiveRecord
 
     test "collection proxy provides a cache_key" do
       developers = projects(:active_record).developers
-      assert_match(/\Adevelopers\/query-(\h+)-(\d+)-(\d+)\Z/, developers.cache_key)
+      assert_match(/\Adevelopers\/query-(\h+)-(\d+)-(\d+)\z/, developers.cache_key)
     end
 
     test "cache_key for loaded collection with zero size" do
@@ -72,18 +128,30 @@ module ActiveRecord
       posts = Post.includes(:comments)
       empty_loaded_collection = posts.first.comments
 
-      assert_match(/\Acomments\/query-(\h+)-0\Z/, empty_loaded_collection.cache_key)
+      assert_match(/\Acomments\/query-(\h+)-0\z/, empty_loaded_collection.cache_key)
     end
 
     test "cache_key for queries with offset which return 0 rows" do
       developers = Developer.offset(20)
-      assert_match(/\Adevelopers\/query-(\h+)-0\Z/, developers.cache_key)
+      assert_match(/\Adevelopers\/query-(\h+)-0\z/, developers.cache_key)
     end
 
     test "cache_key with a relation having selected columns" do
       developers = Developer.select(:salary)
 
-      assert_match(/\Adevelopers\/query-(\h+)-(\d+)-(\d+)\Z/, developers.cache_key)
+      assert_match(/\Adevelopers\/query-(\h+)-(\d+)-(\d+)\z/, developers.cache_key)
+    end
+
+    test "cache_key with a relation having distinct and order" do
+      developers = Developer.distinct.order(:salary).limit(5)
+
+      assert_match(/\Adevelopers\/query-(\h+)-(\d+)-(\d+)\z/, developers.cache_key)
+    end
+
+    test "cache_key with a relation having custom select and order" do
+      developers = Developer.select("name AS dev_name").order("dev_name DESC").limit(5)
+
+      assert_match(/\Adevelopers\/query-(\h+)-(\d+)-(\d+)\z/, developers.cache_key)
     end
   end
 end
diff --git a/activerecord/test/cases/column_alias_test.rb b/activerecord/test/cases/column_alias_test.rb
index 40707d9cb2..a883d21fb8 100644
--- a/activerecord/test/cases/column_alias_test.rb
+++ b/activerecord/test/cases/column_alias_test.rb
@@ -1,17 +1,19 @@
+# frozen_string_literal: true
+
 require "cases/helper"
-require 'models/topic'
+require "models/topic"
 
 class TestColumnAlias < ActiveRecord::TestCase
   fixtures :topics
 
-  QUERY = if 'Oracle' == ActiveRecord::Base.connection.adapter_name
-            'SELECT id AS pk FROM topics WHERE ROWNUM < 2'
-          else
-            'SELECT id AS pk FROM topics'
-          end
+  QUERY = if "Oracle" == ActiveRecord::Base.connection.adapter_name
+    "SELECT id AS pk FROM topics WHERE ROWNUM < 2"
+  else
+    "SELECT id AS pk FROM topics"
+  end
 
   def test_column_alias
     records = Topic.connection.select_all(QUERY)
-    assert_equal 'pk', records[0].keys[0]
+    assert_equal "pk", records[0].keys[0]
   end
 end
diff --git a/activerecord/test/cases/column_definition_test.rb b/activerecord/test/cases/column_definition_test.rb
index 81162b7e98..cbd2b44589 100644
--- a/activerecord/test/cases/column_definition_test.rb
+++ b/activerecord/test/cases/column_definition_test.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require "cases/helper"
 
 module ActiveRecord
@@ -6,86 +8,26 @@ module ActiveRecord
       def setup
         @adapter = AbstractAdapter.new(nil)
         def @adapter.native_database_types
-          {:string => "varchar"}
+          { string: "varchar" }
         end
-        @viz = @adapter.schema_creation
+        @viz = @adapter.send(:schema_creation)
       end
 
       # Avoid column definitions in create table statements like:
       # `title` varchar(255) DEFAULT NULL
       def test_should_not_include_default_clause_when_default_is_null
-        column = Column.new("title", nil, SqlTypeMetadata.new(limit: 20))
-        column_def = ColumnDefinition.new(
-          column.name, "string",
-          column.limit, column.precision, column.scale, column.default, column.null)
-          assert_equal "title varchar(20)", @viz.accept(column_def)
+        column_def = ColumnDefinition.new("title", "string", limit: 20)
+        assert_equal "title varchar(20)", @viz.accept(column_def)
       end
 
       def test_should_include_default_clause_when_default_is_present
-        column = Column.new("title", "Hello", SqlTypeMetadata.new(limit: 20))
-        column_def = ColumnDefinition.new(
-          column.name, "string",
-          column.limit, column.precision, column.scale, column.default, column.null)
-          assert_equal %Q{title varchar(20) DEFAULT 'Hello'}, @viz.accept(column_def)
+        column_def = ColumnDefinition.new("title", "string", limit: 20, default: "Hello")
+        assert_equal "title varchar(20) DEFAULT 'Hello'", @viz.accept(column_def)
       end
 
       def test_should_specify_not_null_if_null_option_is_false
-        type_metadata = SqlTypeMetadata.new(limit: 20)
-        column = Column.new("title", "Hello", type_metadata, false)
-        column_def = ColumnDefinition.new(
-          column.name, "string",
-          column.limit, column.precision, column.scale, column.default, column.null)
-          assert_equal %Q{title varchar(20) DEFAULT 'Hello' NOT NULL}, @viz.accept(column_def)
-      end
-
-      if current_adapter?(:Mysql2Adapter)
-        def test_should_set_default_for_mysql_binary_data_types
-          type = SqlTypeMetadata.new(type: :binary, sql_type: "binary(1)")
-          binary_column = MySQL::Column.new("title", "a", type)
-          assert_equal "a", binary_column.default
-
-          type = SqlTypeMetadata.new(type: :binary, sql_type: "varbinary")
-          varbinary_column = MySQL::Column.new("title", "a", type)
-          assert_equal "a", varbinary_column.default
-        end
-
-        def test_should_be_empty_string_default_for_mysql_binary_data_types
-          type = SqlTypeMetadata.new(type: :binary, sql_type: "binary(1)")
-          binary_column = MySQL::Column.new("title", "", type, false)
-          assert_equal "", binary_column.default
-
-          type = SqlTypeMetadata.new(type: :binary, sql_type: "varbinary")
-          varbinary_column = MySQL::Column.new("title", "", type, false)
-          assert_equal "", varbinary_column.default
-        end
-
-        def test_should_not_set_default_for_blob_and_text_data_types
-          assert_raise ArgumentError do
-            MySQL::Column.new("title", "a", SqlTypeMetadata.new(sql_type: "blob"))
-          end
-
-          text_type = MySQL::TypeMetadata.new(
-            SqlTypeMetadata.new(type: :text))
-          assert_raise ArgumentError do
-            MySQL::Column.new("title", "Hello", text_type)
-          end
-
-          text_column = MySQL::Column.new("title", nil, text_type)
-          assert_equal nil, text_column.default
-
-          not_null_text_column = MySQL::Column.new("title", nil, text_type, false)
-          assert_equal "", not_null_text_column.default
-        end
-
-        def test_has_default_should_return_false_for_blob_and_text_data_types
-          binary_type = SqlTypeMetadata.new(sql_type: "blob")
-          blob_column = MySQL::Column.new("title", nil, binary_type)
-          assert !blob_column.has_default?
-
-          text_type = SqlTypeMetadata.new(type: :text)
-          text_column = MySQL::Column.new("title", nil, text_type)
-          assert !text_column.has_default?
-        end
+        column_def = ColumnDefinition.new("title", "string", limit: 20, default: "Hello", null: false)
+        assert_equal "title varchar(20) DEFAULT 'Hello' NOT NULL", @viz.accept(column_def)
       end
     end
   end
diff --git a/activerecord/test/cases/comment_test.rb b/activerecord/test/cases/comment_test.rb
index 839fdbe578..584e03d196 100644
--- a/activerecord/test/cases/comment_test.rb
+++ b/activerecord/test/cases/comment_test.rb
@@ -1,139 +1,168 @@
-require 'cases/helper'
-require 'support/schema_dumping_helper'
+# frozen_string_literal: true
 
-if ActiveRecord::Base.connection.supports_comments?
+require "cases/helper"
+require "support/schema_dumping_helper"
 
-class CommentTest < ActiveRecord::TestCase
-  include SchemaDumpingHelper
+if ActiveRecord::Base.connection.supports_comments?
+  class CommentTest < ActiveRecord::TestCase
+    include SchemaDumpingHelper
 
-  class Commented < ActiveRecord::Base
-    self.table_name = 'commenteds'
-  end
+    class Commented < ActiveRecord::Base
+      self.table_name = "commenteds"
+    end
 
-  class BlankComment < ActiveRecord::Base
-  end
+    class BlankComment < ActiveRecord::Base
+    end
 
-  setup do
-    @connection = ActiveRecord::Base.connection
+    setup do
+      @connection = ActiveRecord::Base.connection
+
+      @connection.create_table("commenteds", comment: "A table with comment", force: true) do |t|
+        t.string  "name",    comment: "Comment should help clarify the column purpose"
+        t.boolean "obvious", comment: "Question is: should you comment obviously named objects?"
+        t.string  "content"
+        t.index   "name",    comment: %Q["Very important" index that powers all the performance.\nAnd it's fun!]
+      end
+
+      @connection.create_table("blank_comments", comment: " ", force: true) do |t|
+        t.string :space_comment, comment: " "
+        t.string :empty_comment, comment: ""
+        t.string :nil_comment, comment: nil
+        t.string :absent_comment
+        t.index :space_comment, comment: " "
+        t.index :empty_comment, comment: ""
+        t.index :nil_comment, comment: nil
+        t.index :absent_comment
+      end
+
+      Commented.reset_column_information
+      BlankComment.reset_column_information
+    end
 
-    @connection.create_table('commenteds', comment: 'A table with comment', force: true) do |t|
-      t.string  'name',    comment: 'Comment should help clarify the column purpose'
-      t.boolean 'obvious', comment: 'Question is: should you comment obviously named objects?'
-      t.string  'content'
-      t.index   'name',    comment: %Q["Very important" index that powers all the performance.\nAnd it's fun!]
+    teardown do
+      @connection.drop_table "commenteds", if_exists: true
+      @connection.drop_table "blank_comments", if_exists: true
     end
 
-    @connection.create_table('blank_comments', comment: ' ', force: true) do |t|
-      t.string :space_comment, comment: ' '
-      t.string :empty_comment, comment: ''
-      t.string :nil_comment, comment: nil
-      t.string :absent_comment
-      t.index :space_comment, comment: ' '
-      t.index :empty_comment, comment: ''
-      t.index :nil_comment, comment: nil
-      t.index :absent_comment
+    def test_column_created_in_block
+      column = Commented.columns_hash["name"]
+      assert_equal :string, column.type
+      assert_equal "Comment should help clarify the column purpose", column.comment
     end
 
-    Commented.reset_column_information
-    BlankComment.reset_column_information
-  end
+    def test_blank_columns_created_in_block
+      %w[ space_comment empty_comment nil_comment absent_comment ].each do |field|
+        column = BlankComment.columns_hash[field]
+        assert_equal :string, column.type
+        assert_nil column.comment
+      end
+    end
 
-  teardown do
-    @connection.drop_table 'commenteds', if_exists: true
-    @connection.drop_table 'blank_comments', if_exists: true
-  end
+    def test_blank_indexes_created_in_block
+      @connection.indexes("blank_comments").each do |index|
+        assert_nil index.comment
+      end
+    end
 
-  def test_column_created_in_block
-    column = Commented.columns_hash['name']
-    assert_equal :string, column.type
-    assert_equal 'Comment should help clarify the column purpose', column.comment
-  end
+    def test_add_column_with_comment_later
+      @connection.add_column :commenteds, :rating, :integer, comment: "I am running out of imagination"
+      Commented.reset_column_information
+      column = Commented.columns_hash["rating"]
 
-  def test_blank_columns_created_in_block
-    %w[ space_comment empty_comment nil_comment absent_comment ].each do |field|
-      column = BlankComment.columns_hash[field]
-      assert_equal :string, column.type
-      assert_nil column.comment
+      assert_equal :integer, column.type
+      assert_equal "I am running out of imagination", column.comment
     end
-  end
 
-  def test_blank_indexes_created_in_block
-    @connection.indexes('blank_comments').each do |index|
-      assert_nil index.comment
+    def test_add_index_with_comment_later
+      unless current_adapter?(:OracleAdapter)
+        @connection.add_index :commenteds, :obvious, name: "idx_obvious", comment: "We need to see obvious comments"
+        index = @connection.indexes("commenteds").find { |idef| idef.name == "idx_obvious" }
+        assert_equal "We need to see obvious comments", index.comment
+      end
     end
-  end
 
-  def test_add_column_with_comment_later
-    @connection.add_column :commenteds, :rating, :integer, comment: 'I am running out of imagination'
-    Commented.reset_column_information
-    column = Commented.columns_hash['rating']
+    def test_add_comment_to_column
+      @connection.change_column :commenteds, :content, :string, comment: "Whoa, content describes itself!"
 
-    assert_equal :integer, column.type
-    assert_equal 'I am running out of imagination', column.comment
-  end
+      Commented.reset_column_information
+      column = Commented.columns_hash["content"]
 
-  def test_add_index_with_comment_later
-    @connection.add_index :commenteds, :obvious, name: 'idx_obvious', comment: 'We need to see obvious comments'
-    index = @connection.indexes('commenteds').find { |idef| idef.name == 'idx_obvious' }
-    assert_equal 'We need to see obvious comments', index.comment
-  end
+      assert_equal :string, column.type
+      assert_equal "Whoa, content describes itself!", column.comment
+    end
 
-  def test_add_comment_to_column
-    @connection.change_column :commenteds, :content, :string, comment: 'Whoa, content describes itself!'
+    def test_remove_comment_from_column
+      @connection.change_column :commenteds, :obvious, :string, comment: nil
 
-    Commented.reset_column_information
-    column = Commented.columns_hash['content']
+      Commented.reset_column_information
+      column = Commented.columns_hash["obvious"]
 
-    assert_equal :string, column.type
-    assert_equal 'Whoa, content describes itself!', column.comment
-  end
+      assert_equal :string, column.type
+      assert_nil column.comment
+    end
 
-  def test_remove_comment_from_column
-    @connection.change_column :commenteds, :obvious, :string, comment: nil
+    def test_schema_dump_with_comments
+      # Do all the stuff from other tests
+      @connection.add_column    :commenteds, :rating, :integer, comment: "I am running out of imagination"
+      @connection.change_column :commenteds, :content, :string, comment: "Whoa, content describes itself!"
+      @connection.change_column :commenteds, :content, :string
+      @connection.change_column :commenteds, :obvious, :string, comment: nil
+      @connection.add_index     :commenteds, :obvious, name: "idx_obvious", comment: "We need to see obvious comments"
+
+      # And check that these changes are reflected in dump
+      output = dump_table_schema "commenteds"
+      assert_match %r[create_table "commenteds",.*\s+comment: "A table with comment"], output
+      assert_match %r[t\.string\s+"name",\s+comment: "Comment should help clarify the column purpose"], output
+      assert_match %r[t\.string\s+"obvious"\n], output
+      assert_match %r[t\.string\s+"content",\s+comment: "Whoa, content describes itself!"], output
+      if current_adapter?(:OracleAdapter)
+        assert_match %r[t\.integer\s+"rating",\s+precision: 38,\s+comment: "I am running out of imagination"], output
+      else
+        assert_match %r[t\.integer\s+"rating",\s+comment: "I am running out of imagination"], output
+        assert_match %r[t\.index\s+.+\s+comment: "\\\"Very important\\\" index that powers all the performance.\\nAnd it's fun!"], output
+        assert_match %r[t\.index\s+.+\s+name: "idx_obvious",\s+comment: "We need to see obvious comments"], output
+      end
+    end
 
-    Commented.reset_column_information
-    column = Commented.columns_hash['obvious']
+    def test_schema_dump_omits_blank_comments
+      output = dump_table_schema "blank_comments"
 
-    assert_equal :string, column.type
-    assert_nil column.comment
-  end
+      assert_match %r[create_table "blank_comments"], output
+      assert_no_match %r[create_table "blank_comments",.+comment:], output
 
-  def test_schema_dump_with_comments
-    # Do all the stuff from other tests
-    @connection.add_column    :commenteds, :rating, :integer, comment: 'I am running out of imagination'
-    @connection.change_column :commenteds, :content, :string, comment: 'Whoa, content describes itself!'
-    @connection.change_column :commenteds, :obvious, :string, comment: nil
-    @connection.add_index     :commenteds, :obvious, name: 'idx_obvious', comment: 'We need to see obvious comments'
-
-    # And check that these changes are reflected in dump
-    output = dump_table_schema 'commenteds'
-    assert_match %r[create_table "commenteds",.+\s+comment: "A table with comment"], output
-    assert_match %r[t\.string\s+"name",\s+comment: "Comment should help clarify the column purpose"], output
-    assert_match %r[t\.string\s+"obvious"\n], output
-    assert_match %r[t\.string\s+"content",\s+comment: "Whoa, content describes itself!"], output
-    assert_match %r[t\.integer\s+"rating",\s+comment: "I am running out of imagination"], output
-    assert_match %r[t\.index\s+.+\s+comment: "\\\"Very important\\\" index that powers all the performance.\\nAnd it's fun!"], output
-    assert_match %r[t\.index\s+.+\s+name: "idx_obvious",.+\s+comment: "We need to see obvious comments"], output
-  end
+      assert_match %r[t\.string\s+"space_comment"\n], output
+      assert_no_match %r[t\.string\s+"space_comment", comment:\n], output
 
-  def test_schema_dump_omits_blank_comments
-    output = dump_table_schema 'blank_comments'
+      assert_match %r[t\.string\s+"empty_comment"\n], output
+      assert_no_match %r[t\.string\s+"empty_comment", comment:\n], output
 
-    assert_match %r[create_table "blank_comments"], output
-    assert_no_match %r[create_table "blank_comments",.+comment:], output
+      assert_match %r[t\.string\s+"nil_comment"\n], output
+      assert_no_match %r[t\.string\s+"nil_comment", comment:\n], output
 
-    assert_match %r[t\.string\s+"space_comment"\n], output
-    assert_no_match %r[t\.string\s+"space_comment", comment:\n], output
+      assert_match %r[t\.string\s+"absent_comment"\n], output
+      assert_no_match %r[t\.string\s+"absent_comment", comment:\n], output
+    end
 
-    assert_match %r[t\.string\s+"empty_comment"\n], output
-    assert_no_match %r[t\.string\s+"empty_comment", comment:\n], output
+    def test_change_table_comment
+      @connection.change_table_comment :commenteds, "Edited table comment"
+      assert_equal "Edited table comment", @connection.table_comment("commenteds")
+    end
 
-    assert_match %r[t\.string\s+"nil_comment"\n], output
-    assert_no_match %r[t\.string\s+"nil_comment", comment:\n], output
+    def test_change_table_comment_to_nil
+      @connection.change_table_comment :commenteds, nil
+      assert_nil @connection.table_comment("commenteds")
+    end
 
-    assert_match %r[t\.string\s+"absent_comment"\n], output
-    assert_no_match %r[t\.string\s+"absent_comment", comment:\n], output
-  end
-end
+    def test_change_column_comment
+      @connection.change_column_comment :commenteds, :name, "Edited column comment"
+      column = Commented.columns_hash["name"]
+      assert_equal "Edited column comment", column.comment
+    end
 
+    def test_change_column_comment_to_nil
+      @connection.change_column_comment :commenteds, :name, nil
+      column = Commented.columns_hash["name"]
+      assert_nil column.comment
+    end
+  end
 end
diff --git a/activerecord/test/cases/connection_adapters/adapter_leasing_test.rb b/activerecord/test/cases/connection_adapters/adapter_leasing_test.rb
index c7ca428ab7..82c6cf8dea 100644
--- a/activerecord/test/cases/connection_adapters/adapter_leasing_test.rb
+++ b/activerecord/test/cases/connection_adapters/adapter_leasing_test.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require "cases/helper"
 
 module ActiveRecord
@@ -17,23 +19,23 @@ module ActiveRecord
       end
 
       def test_in_use?
-        assert_not @adapter.in_use?, 'adapter is not in use'
-        assert @adapter.lease, 'lease adapter'
-        assert @adapter.in_use?, 'adapter is in use'
+        assert_not @adapter.in_use?, "adapter is not in use"
+        assert @adapter.lease, "lease adapter"
+        assert @adapter.in_use?, "adapter is in use"
       end
 
       def test_lease_twice
-        assert @adapter.lease, 'should lease adapter'
+        assert @adapter.lease, "should lease adapter"
         assert_raises(ActiveRecordError) do
           @adapter.lease
         end
       end
 
       def test_expire_mutates_in_use
-        assert @adapter.lease, 'lease adapter'
-        assert @adapter.in_use?, 'adapter is in use'
+        assert @adapter.lease, "lease adapter"
+        assert @adapter.in_use?, "adapter is in use"
         @adapter.expire
-        assert_not @adapter.in_use?, 'adapter is in use'
+        assert_not @adapter.in_use?, "adapter is in use"
       end
 
       def test_close
diff --git a/activerecord/test/cases/connection_adapters/connection_handler_test.rb b/activerecord/test/cases/connection_adapters/connection_handler_test.rb
index a019cc6490..603ed63a8c 100644
--- a/activerecord/test/cases/connection_adapters/connection_handler_test.rb
+++ b/activerecord/test/cases/connection_adapters/connection_handler_test.rb
@@ -1,23 +1,101 @@
+# frozen_string_literal: true
+
 require "cases/helper"
+require "models/person"
 
 module ActiveRecord
   module ConnectionAdapters
     class ConnectionHandlerTest < ActiveRecord::TestCase
+      self.use_transactional_tests = false
+
+      fixtures :people
+
       def setup
         @handler = ConnectionHandler.new
         @spec_name = "primary"
-        @pool    = @handler.establish_connection(ActiveRecord::Base.configurations['arunit'])
+        @pool = @handler.establish_connection(ActiveRecord::Base.configurations["arunit"])
+      end
+
+      def test_default_env_fall_back_to_default_env_when_rails_env_or_rack_env_is_empty_string
+        original_rails_env = ENV["RAILS_ENV"]
+        original_rack_env  = ENV["RACK_ENV"]
+        ENV["RAILS_ENV"]   = ENV["RACK_ENV"] = ""
+
+        assert_equal "default_env", ActiveRecord::ConnectionHandling::DEFAULT_ENV.call
+      ensure
+        ENV["RAILS_ENV"] = original_rails_env
+        ENV["RACK_ENV"]  = original_rack_env
       end
 
       def test_establish_connection_uses_spec_name
-        config = {"readonly" => {"adapter" => 'sqlite3'}}
+        config = { "readonly" => { "adapter" => "sqlite3" } }
         resolver = ConnectionAdapters::ConnectionSpecification::Resolver.new(config)
         spec =   resolver.spec(:readonly)
         @handler.establish_connection(spec.to_hash)
 
-        assert_not_nil @handler.retrieve_connection_pool('readonly')
+        assert_not_nil @handler.retrieve_connection_pool("readonly")
+      ensure
+        @handler.remove_connection("readonly")
+      end
+
+      def test_establish_connection_using_3_levels_config
+        previous_env, ENV["RAILS_ENV"] = ENV["RAILS_ENV"], "default_env"
+
+        config = {
+          "default_env" => {
+            "readonly" => { "adapter" => "sqlite3", "database" => "db/readonly.sqlite3" },
+            "primary"  => { "adapter" => "sqlite3", "database" => "db/primary.sqlite3" }
+          },
+          "another_env" => {
+            "readonly" => { "adapter" => "sqlite3", "database" => "db/bad-readonly.sqlite3" },
+            "primary"  => { "adapter" => "sqlite3", "database" => "db/bad-primary.sqlite3" }
+          },
+          "common" => { "adapter" => "sqlite3", "database" => "db/common.sqlite3" }
+        }
+        @prev_configs, ActiveRecord::Base.configurations = ActiveRecord::Base.configurations, config
+
+        @handler.establish_connection(:common)
+        @handler.establish_connection(:primary)
+        @handler.establish_connection(:readonly)
+
+        assert_not_nil pool = @handler.retrieve_connection_pool("readonly")
+        assert_equal "db/readonly.sqlite3", pool.spec.config[:database]
+
+        assert_not_nil pool = @handler.retrieve_connection_pool("primary")
+        assert_equal "db/primary.sqlite3", pool.spec.config[:database]
+
+        assert_not_nil pool = @handler.retrieve_connection_pool("common")
+        assert_equal "db/common.sqlite3", pool.spec.config[:database]
       ensure
-        @handler.remove_connection('readonly')
+        ActiveRecord::Base.configurations = @prev_configs
+        ENV["RAILS_ENV"] = previous_env
+      end
+
+      def test_establish_connection_using_two_level_configurations
+        config = { "development" => { "adapter" => "sqlite3", "database" => "db/primary.sqlite3" } }
+        @prev_configs, ActiveRecord::Base.configurations = ActiveRecord::Base.configurations, config
+
+        @handler.establish_connection(:development)
+
+        assert_not_nil pool = @handler.retrieve_connection_pool("development")
+        assert_equal "db/primary.sqlite3", pool.spec.config[:database]
+      ensure
+        ActiveRecord::Base.configurations = @prev_configs
+      end
+
+      def test_establish_connection_using_top_level_key_in_two_level_config
+        config = {
+          "development" => { "adapter" => "sqlite3", "database" => "db/primary.sqlite3" },
+          "development_readonly" => { "adapter" => "sqlite3", "database" => "db/readonly.sqlite3" }
+        }
+        @prev_configs, ActiveRecord::Base.configurations = ActiveRecord::Base.configurations, config
+
+        @handler.establish_connection(:development_readonly)
+
+        assert_not_nil pool = @handler.retrieve_connection_pool("development_readonly")
+        assert_equal "db/readonly.sqlite3", pool.spec.config[:database]
+      ensure
+        ActiveRecord::Base.configurations = @prev_configs
       end
 
       def test_retrieve_connection
@@ -66,9 +144,36 @@ module ActiveRecord
           rd.close
         end
 
+        def test_forked_child_doesnt_mangle_parent_connection
+          object_id = ActiveRecord::Base.connection.object_id
+          assert ActiveRecord::Base.connection.active?
+
+          rd, wr = IO.pipe
+          rd.binmode
+          wr.binmode
+
+          pid = fork {
+            rd.close
+            if ActiveRecord::Base.connection.active?
+              wr.write Marshal.dump ActiveRecord::Base.connection.object_id
+            end
+            wr.close
+
+            exit # allow finalizers to run
+          }
+
+          wr.close
+
+          Process.waitpid pid
+          assert_not_equal object_id, Marshal.load(rd.read)
+          rd.close
+
+          assert_equal 3, ActiveRecord::Base.connection.select_value("SELECT COUNT(*) FROM people")
+        end
+
         def test_retrieve_connection_pool_copies_schema_cache_from_ancestor_pool
           @pool.schema_cache = @pool.connection.schema_cache
-          @pool.schema_cache.add('posts')
+          @pool.schema_cache.add("posts")
 
           rd, wr = IO.pipe
           rd.binmode
@@ -89,18 +194,53 @@ module ActiveRecord
           rd.close
         end
 
+        def test_pool_from_any_process_for_uses_most_recent_spec
+          skip unless current_adapter?(:SQLite3Adapter)
+
+          file = Tempfile.new "lol.sqlite3"
+
+          rd, wr = IO.pipe
+          rd.binmode
+          wr.binmode
+
+          pid = fork do
+            ActiveRecord::Base.configurations["arunit"]["database"] = file.path
+            ActiveRecord::Base.establish_connection(:arunit)
+
+            pid2 = fork do
+              wr.write ActiveRecord::Base.connection_config[:database]
+              wr.close
+            end
+
+            Process.waitpid pid2
+          end
+
+          Process.waitpid pid
+
+          wr.close
+
+          assert_equal file.path, rd.read
+
+          rd.close
+        ensure
+          if file
+            file.close
+            file.unlink
+          end
+        end
+
         def test_a_class_using_custom_pool_and_switching_back_to_primary
-          klass2 = Class.new(Base) { def self.name; 'klass2'; end }
+          klass2 = Class.new(Base) { def self.name; "klass2"; end }
 
-          assert_equal klass2.connection.object_id, ActiveRecord::Base.connection.object_id
+          assert_same klass2.connection, ActiveRecord::Base.connection
 
           pool = klass2.establish_connection(ActiveRecord::Base.connection_pool.spec.config)
-          assert_equal klass2.connection.object_id, pool.connection.object_id
-          refute_equal klass2.connection.object_id, ActiveRecord::Base.connection.object_id
+          assert_same klass2.connection, pool.connection
+          refute_same klass2.connection, ActiveRecord::Base.connection
 
           klass2.remove_connection
 
-          assert_equal klass2.connection.object_id, ActiveRecord::Base.connection.object_id
+          assert_same klass2.connection, ActiveRecord::Base.connection
         end
 
         def test_connection_specification_name_should_fallback_to_parent
@@ -113,10 +253,10 @@ module ActiveRecord
         end
 
         def test_remove_connection_should_not_remove_parent
-          klass2 = Class.new(Base) { def self.name; 'klass2'; end }
+          klass2 = Class.new(Base) { def self.name; "klass2"; end }
           klass2.remove_connection
-          refute_nil ActiveRecord::Base.connection.object_id
-          assert_equal klass2.connection.object_id, ActiveRecord::Base.connection.object_id
+          refute_nil ActiveRecord::Base.connection
+          assert_same klass2.connection, ActiveRecord::Base.connection
         end
       end
     end
diff --git a/activerecord/test/cases/connection_adapters/connection_specification_test.rb b/activerecord/test/cases/connection_adapters/connection_specification_test.rb
index d204fce59f..f81b73c344 100644
--- a/activerecord/test/cases/connection_adapters/connection_specification_test.rb
+++ b/activerecord/test/cases/connection_adapters/connection_specification_test.rb
@@ -1,10 +1,12 @@
+# frozen_string_literal: true
+
 require "cases/helper"
 
 module ActiveRecord
   module ConnectionAdapters
     class ConnectionSpecificationTest < ActiveRecord::TestCase
       def test_dup_deep_copy_config
-        spec = ConnectionSpecification.new("primary", { :a => :b }, "bar")
+        spec = ConnectionSpecification.new("primary", { a: :b }, "bar")
         assert_not_equal(spec.config.object_id, spec.dup.config.object_id)
       end
     end
diff --git a/activerecord/test/cases/connection_adapters/merge_and_resolve_default_url_config_test.rb b/activerecord/test/cases/connection_adapters/merge_and_resolve_default_url_config_test.rb
index f25b85e8a7..1b64324cc4 100644
--- a/activerecord/test/cases/connection_adapters/merge_and_resolve_default_url_config_test.rb
+++ b/activerecord/test/cases/connection_adapters/merge_and_resolve_default_url_config_test.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require "cases/helper"
 
 module ActiveRecord
@@ -24,54 +26,54 @@ module ActiveRecord
       end
 
       def test_resolver_with_database_uri_and_current_env_symbol_key
-        ENV['DATABASE_URL'] = "postgres://localhost/foo"
+        ENV["DATABASE_URL"] = "postgres://localhost/foo"
         config   = { "not_production" => {  "adapter" => "not_postgres", "database" => "not_foo" } }
         actual   = resolve_spec(:default_env, config)
-        expected = { "adapter"=>"postgresql", "database"=>"foo", "host"=>"localhost", "name"=>"default_env" }
+        expected = { "adapter" => "postgresql", "database" => "foo", "host" => "localhost", "name" => "default_env" }
         assert_equal expected, actual
       end
 
       def test_resolver_with_database_uri_and_current_env_symbol_key_and_rails_env
-        ENV['DATABASE_URL'] = "postgres://localhost/foo"
-        ENV['RAILS_ENV']    = "foo"
+        ENV["DATABASE_URL"] = "postgres://localhost/foo"
+        ENV["RAILS_ENV"]    = "foo"
 
         config   = { "not_production" => { "adapter" => "not_postgres", "database" => "not_foo" } }
         actual   = resolve_spec(:foo, config)
-        expected = { "adapter" => "postgresql", "database" => "foo", "host" => "localhost","name"=>"foo" }
+        expected = { "adapter" => "postgresql", "database" => "foo", "host" => "localhost", "name" => "foo" }
         assert_equal expected, actual
       end
 
       def test_resolver_with_database_uri_and_current_env_symbol_key_and_rack_env
-        ENV['DATABASE_URL'] = "postgres://localhost/foo"
-        ENV['RACK_ENV']     = "foo"
+        ENV["DATABASE_URL"] = "postgres://localhost/foo"
+        ENV["RACK_ENV"]     = "foo"
 
         config   = { "not_production" => { "adapter" => "not_postgres", "database" => "not_foo" } }
         actual   = resolve_spec(:foo, config)
-        expected = { "adapter" => "postgresql", "database" => "foo", "host" => "localhost","name"=>"foo" }
+        expected = { "adapter" => "postgresql", "database" => "foo", "host" => "localhost", "name" => "foo" }
         assert_equal expected, actual
       end
 
       def test_resolver_with_database_uri_and_known_key
-        ENV['DATABASE_URL'] = "postgres://localhost/foo"
+        ENV["DATABASE_URL"] = "postgres://localhost/foo"
         config   = { "production" => { "adapter" => "not_postgres", "database" => "not_foo", "host" => "localhost" } }
         actual   = resolve_spec(:production, config)
-        expected = { "adapter"=>"not_postgres", "database"=>"not_foo", "host"=>"localhost", "name"=>"production" }
+        expected = { "adapter" => "not_postgres", "database" => "not_foo", "host" => "localhost", "name" => "production" }
         assert_equal expected, actual
       end
 
       def test_resolver_with_database_uri_and_unknown_symbol_key
-        ENV['DATABASE_URL'] = "postgres://localhost/foo"
-        config   = { "not_production" => {  "adapter" => "not_postgres", "database" => "not_foo" } }
+        ENV["DATABASE_URL"] = "postgres://localhost/foo"
+        config = { "not_production" => {  "adapter" => "not_postgres", "database" => "not_foo" } }
         assert_raises AdapterNotSpecified do
           resolve_spec(:production, config)
         end
       end
 
       def test_resolver_with_database_uri_and_supplied_url
-        ENV['DATABASE_URL'] = "not-postgres://not-localhost/not_foo"
+        ENV["DATABASE_URL"] = "not-postgres://not-localhost/not_foo"
         config   = { "production" => {  "adapter" => "also_not_postgres", "database" => "also_not_foo" } }
         actual   = resolve_spec("postgres://localhost/foo", config)
-        expected = { "adapter"=>"postgresql", "database"=>"foo", "host"=>"localhost" }
+        expected = { "adapter" => "postgresql", "database" => "foo", "host" => "localhost" }
         assert_equal expected, actual
       end
 
@@ -82,18 +84,18 @@ module ActiveRecord
       end
 
       def test_environment_does_not_exist_in_config_url_does_exist
-        ENV['DATABASE_URL'] = "postgres://localhost/foo"
+        ENV["DATABASE_URL"] = "postgres://localhost/foo"
         config      = { "not_default_env" => {  "adapter" => "not_postgres", "database" => "not_foo" } }
         actual      = resolve_config(config)
-        expect_prod = { "adapter"=>"postgresql", "database"=>"foo", "host"=>"localhost" }
+        expect_prod = { "adapter" => "postgresql", "database" => "foo", "host" => "localhost" }
         assert_equal expect_prod, actual["default_env"]
       end
 
       def test_url_with_hyphenated_scheme
-        ENV['DATABASE_URL'] = "ibm-db://localhost/foo"
+        ENV["DATABASE_URL"] = "ibm-db://localhost/foo"
         config   = { "default_env" => { "adapter" => "not_postgres", "database" => "not_foo", "host" => "localhost" } }
         actual   = resolve_spec(:default_env, config)
-        expected = { "adapter"=>"ibm_db", "database"=>"foo", "host"=>"localhost", "name"=>"default_env" }
+        expected = { "adapter" => "ibm_db", "database" => "foo", "host" => "localhost", "name" => "default_env" }
         assert_equal expected, actual
       end
 
@@ -134,7 +136,7 @@ module ActiveRecord
       end
 
       def test_blank_with_database_url
-        ENV['DATABASE_URL'] = "postgres://localhost/foo"
+        ENV["DATABASE_URL"] = "postgres://localhost/foo"
 
         config   = {}
         actual   = resolve_config(config)
@@ -142,18 +144,18 @@ module ActiveRecord
                      "database" => "foo",
                      "host"     => "localhost" }
         assert_equal expected, actual["default_env"]
-        assert_equal nil,      actual["production"]
-        assert_equal nil,      actual["development"]
-        assert_equal nil,      actual["test"]
-        assert_equal nil,      actual[:default_env]
-        assert_equal nil,      actual[:production]
-        assert_equal nil,      actual[:development]
-        assert_equal nil,      actual[:test]
+        assert_nil actual["production"]
+        assert_nil actual["development"]
+        assert_nil actual["test"]
+        assert_nil actual[:default_env]
+        assert_nil actual[:production]
+        assert_nil actual[:development]
+        assert_nil actual[:test]
       end
 
       def test_blank_with_database_url_with_rails_env
-        ENV['RAILS_ENV'] = "not_production"
-        ENV['DATABASE_URL'] = "postgres://localhost/foo"
+        ENV["RAILS_ENV"] = "not_production"
+        ENV["DATABASE_URL"] = "postgres://localhost/foo"
 
         config   = {}
         actual   = resolve_config(config)
@@ -162,20 +164,20 @@ module ActiveRecord
                      "host"     => "localhost" }
 
         assert_equal expected, actual["not_production"]
-        assert_equal nil,      actual["production"]
-        assert_equal nil,      actual["default_env"]
-        assert_equal nil,      actual["development"]
-        assert_equal nil,      actual["test"]
-        assert_equal nil,      actual[:default_env]
-        assert_equal nil,      actual[:not_production]
-        assert_equal nil,      actual[:production]
-        assert_equal nil,      actual[:development]
-        assert_equal nil,      actual[:test]
+        assert_nil actual["production"]
+        assert_nil actual["default_env"]
+        assert_nil actual["development"]
+        assert_nil actual["test"]
+        assert_nil actual[:default_env]
+        assert_nil actual[:not_production]
+        assert_nil actual[:production]
+        assert_nil actual[:development]
+        assert_nil actual[:test]
       end
 
       def test_blank_with_database_url_with_rack_env
-        ENV['RACK_ENV'] = "not_production"
-        ENV['DATABASE_URL'] = "postgres://localhost/foo"
+        ENV["RACK_ENV"] = "not_production"
+        ENV["DATABASE_URL"] = "postgres://localhost/foo"
 
         config   = {}
         actual   = resolve_config(config)
@@ -184,19 +186,19 @@ module ActiveRecord
                      "host"     => "localhost" }
 
         assert_equal expected, actual["not_production"]
-        assert_equal nil,      actual["production"]
-        assert_equal nil,      actual["default_env"]
-        assert_equal nil,      actual["development"]
-        assert_equal nil,      actual["test"]
-        assert_equal nil,      actual[:default_env]
-        assert_equal nil,      actual[:not_production]
-        assert_equal nil,      actual[:production]
-        assert_equal nil,      actual[:development]
-        assert_equal nil,      actual[:test]
+        assert_nil actual["production"]
+        assert_nil actual["default_env"]
+        assert_nil actual["development"]
+        assert_nil actual["test"]
+        assert_nil actual[:default_env]
+        assert_nil actual[:not_production]
+        assert_nil actual[:production]
+        assert_nil actual[:development]
+        assert_nil actual[:test]
       end
 
       def test_database_url_with_ipv6_host_and_port
-        ENV['DATABASE_URL'] = "postgres://[::1]:5454/foo"
+        ENV["DATABASE_URL"] = "postgres://[::1]:5454/foo"
 
         config   = {}
         actual   = resolve_config(config)
@@ -208,12 +210,12 @@ module ActiveRecord
       end
 
       def test_url_sub_key_with_database_url
-        ENV['DATABASE_URL'] = "NOT-POSTGRES://localhost/NOT_FOO"
+        ENV["DATABASE_URL"] = "NOT-POSTGRES://localhost/NOT_FOO"
 
         config   = { "default_env" => { "url" => "postgres://localhost/foo" } }
         actual   = resolve_config(config)
         expected = { "default_env" =>
-                    { "adapter"  => "postgresql",
+                    { "adapter" => "postgresql",
                        "database" => "foo",
                        "host"     => "localhost"
                       }
@@ -222,9 +224,9 @@ module ActiveRecord
       end
 
       def test_merge_no_conflicts_with_database_url
-        ENV['DATABASE_URL'] = "postgres://localhost/foo"
+        ENV["DATABASE_URL"] = "postgres://localhost/foo"
 
-        config   = {"default_env" => { "pool" => "5" } }
+        config   = { "default_env" => { "pool" => "5" } }
         actual   = resolve_config(config)
         expected = { "default_env" =>
                      { "adapter"  => "postgresql",
@@ -237,9 +239,9 @@ module ActiveRecord
       end
 
       def test_merge_conflicts_with_database_url
-        ENV['DATABASE_URL'] = "postgres://localhost/foo"
+        ENV["DATABASE_URL"] = "postgres://localhost/foo"
 
-        config   = {"default_env" => { "adapter" => "NOT-POSTGRES", "database" => "NOT-FOO", "pool" => "5" } }
+        config   = { "default_env" => { "adapter" => "NOT-POSTGRES", "database" => "NOT-FOO", "pool" => "5" } }
         actual   = resolve_config(config)
         expected = { "default_env" =>
                      { "adapter"  => "postgresql",
diff --git a/activerecord/test/cases/connection_adapters/mysql_type_lookup_test.rb b/activerecord/test/cases/connection_adapters/mysql_type_lookup_test.rb
index f2b1d9e4e7..02e76ce146 100644
--- a/activerecord/test/cases/connection_adapters/mysql_type_lookup_test.rb
+++ b/activerecord/test/cases/connection_adapters/mysql_type_lookup_test.rb
@@ -1,69 +1,78 @@
+# frozen_string_literal: true
+
 require "cases/helper"
+require "support/connection_helper"
 
 if current_adapter?(:Mysql2Adapter)
-module ActiveRecord
-  module ConnectionAdapters
-    class MysqlTypeLookupTest < ActiveRecord::TestCase
-      setup do
-        @connection = ActiveRecord::Base.connection
-      end
+  module ActiveRecord
+    module ConnectionAdapters
+      class MysqlTypeLookupTest < ActiveRecord::TestCase
+        include ConnectionHelper
 
-      def test_boolean_types
-        emulate_booleans(true) do
-          assert_lookup_type :boolean, 'tinyint(1)'
-          assert_lookup_type :boolean, 'TINYINT(1)'
+        setup do
+          @connection = ActiveRecord::Base.connection
         end
-      end
 
-      def test_string_types
-        assert_lookup_type :string, "enum('one', 'two', 'three')"
-        assert_lookup_type :string, "ENUM('one', 'two', 'three')"
-        assert_lookup_type :string, "set('one', 'two', 'three')"
-        assert_lookup_type :string, "SET('one', 'two', 'three')"
-      end
+        def teardown
+          reset_connection
+        end
 
-      def test_set_type_with_value_matching_other_type
-        assert_lookup_type :string, "SET('unicode', '8bit', 'none', 'time')"
-      end
+        def test_boolean_types
+          emulate_booleans(true) do
+            assert_lookup_type :boolean, "tinyint(1)"
+            assert_lookup_type :boolean, "TINYINT(1)"
+          end
+        end
 
-      def test_enum_type_with_value_matching_other_type
-        assert_lookup_type :string, "ENUM('unicode', '8bit', 'none')"
-      end
+        def test_string_types
+          assert_lookup_type :string, "enum('one', 'two', 'three')"
+          assert_lookup_type :string, "ENUM('one', 'two', 'three')"
+          assert_lookup_type :string, "set('one', 'two', 'three')"
+          assert_lookup_type :string, "SET('one', 'two', 'three')"
+        end
 
-      def test_binary_types
-        assert_lookup_type :binary, 'bit'
-        assert_lookup_type :binary, 'BIT'
-      end
+        def test_set_type_with_value_matching_other_type
+          assert_lookup_type :string, "SET('unicode', '8bit', 'none', 'time')"
+        end
 
-      def test_integer_types
-        emulate_booleans(false) do
-          assert_lookup_type :integer, 'tinyint(1)'
-          assert_lookup_type :integer, 'TINYINT(1)'
-          assert_lookup_type :integer, 'year'
-          assert_lookup_type :integer, 'YEAR'
+        def test_enum_type_with_value_matching_other_type
+          assert_lookup_type :string, "ENUM('unicode', '8bit', 'none')"
         end
-      end
 
-      private
+        def test_binary_types
+          assert_lookup_type :binary, "bit"
+          assert_lookup_type :binary, "BIT"
+        end
 
-      def assert_lookup_type(type, lookup)
-        cast_type = @connection.type_map.lookup(lookup)
-        assert_equal type, cast_type.type
-      end
+        def test_integer_types
+          emulate_booleans(false) do
+            assert_lookup_type :integer, "tinyint(1)"
+            assert_lookup_type :integer, "TINYINT(1)"
+            assert_lookup_type :integer, "year"
+            assert_lookup_type :integer, "YEAR"
+          end
+        end
 
-      def emulate_booleans(value)
-        old_emulate_booleans = @connection.emulate_booleans
-        change_emulate_booleans(value)
-        yield
-      ensure
-        change_emulate_booleans(old_emulate_booleans)
-      end
+        private
+
+          def assert_lookup_type(type, lookup)
+            cast_type = @connection.send(:type_map).lookup(lookup)
+            assert_equal type, cast_type.type
+          end
 
-      def change_emulate_booleans(value)
-        @connection.emulate_booleans = value
-        @connection.clear_cache!
+          def emulate_booleans(value)
+            old_emulate_booleans = @connection.emulate_booleans
+            change_emulate_booleans(value)
+            yield
+          ensure
+            change_emulate_booleans(old_emulate_booleans)
+          end
+
+          def change_emulate_booleans(value)
+            @connection.emulate_booleans = value
+            @connection.clear_cache!
+          end
       end
     end
   end
 end
-end
diff --git a/activerecord/test/cases/connection_adapters/quoting_test.rb b/activerecord/test/cases/connection_adapters/quoting_test.rb
deleted file mode 100644
index 59dcb96ebc..0000000000
--- a/activerecord/test/cases/connection_adapters/quoting_test.rb
+++ /dev/null
@@ -1,13 +0,0 @@
-require "cases/helper"
-
-module ActiveRecord
-  module ConnectionAdapters
-    module Quoting
-      class QuotingTest < ActiveRecord::TestCase
-        def test_quoting_classes
-          assert_equal "'Object'", AbstractAdapter.new(nil).quote(Object)
-        end
-      end
-    end
-  end
-end
diff --git a/activerecord/test/cases/connection_adapters/schema_cache_test.rb b/activerecord/test/cases/connection_adapters/schema_cache_test.rb
index db832fe55d..006be9e65d 100644
--- a/activerecord/test/cases/connection_adapters/schema_cache_test.rb
+++ b/activerecord/test/cases/connection_adapters/schema_cache_test.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require "cases/helper"
 
 module ActiveRecord
@@ -9,28 +11,55 @@ module ActiveRecord
       end
 
       def test_primary_key
-        assert_equal 'id', @cache.primary_keys('posts')
+        assert_equal "id", @cache.primary_keys("posts")
+      end
+
+      def test_yaml_dump_and_load
+        @cache.columns("posts")
+        @cache.columns_hash("posts")
+        @cache.data_sources("posts")
+        @cache.primary_keys("posts")
+
+        new_cache = YAML.load(YAML.dump(@cache))
+        assert_no_queries do
+          assert_equal 11, new_cache.columns("posts").size
+          assert_equal 11, new_cache.columns_hash("posts").size
+          assert new_cache.data_sources("posts")
+          assert_equal "id", new_cache.primary_keys("posts")
+        end
+      end
+
+      def test_yaml_loads_5_1_dump
+        body = File.open(schema_dump_path).read
+        cache = YAML.load(body)
+
+        assert_no_queries do
+          assert_equal 11, cache.columns("posts").size
+          assert_equal 11, cache.columns_hash("posts").size
+          assert cache.data_sources("posts")
+          assert_equal "id", cache.primary_keys("posts")
+        end
       end
 
       def test_primary_key_for_non_existent_table
-        assert_nil @cache.primary_keys('omgponies')
+        assert_nil @cache.primary_keys("omgponies")
       end
 
       def test_caches_columns
-        columns = @cache.columns('posts')
-        assert_equal columns, @cache.columns('posts')
+        columns = @cache.columns("posts")
+        assert_equal columns, @cache.columns("posts")
       end
 
       def test_caches_columns_hash
-        columns_hash = @cache.columns_hash('posts')
-        assert_equal columns_hash, @cache.columns_hash('posts')
+        columns_hash = @cache.columns_hash("posts")
+        assert_equal columns_hash, @cache.columns_hash("posts")
       end
 
       def test_clearing
-        @cache.columns('posts')
-        @cache.columns_hash('posts')
-        @cache.data_sources('posts')
-        @cache.primary_keys('posts')
+        @cache.columns("posts")
+        @cache.columns_hash("posts")
+        @cache.data_sources("posts")
+        @cache.primary_keys("posts")
 
         @cache.clear!
 
@@ -38,24 +67,35 @@ module ActiveRecord
       end
 
       def test_dump_and_load
-        @cache.columns('posts')
-        @cache.columns_hash('posts')
-        @cache.data_sources('posts')
-        @cache.primary_keys('posts')
+        @cache.columns("posts")
+        @cache.columns_hash("posts")
+        @cache.data_sources("posts")
+        @cache.primary_keys("posts")
 
         @cache = Marshal.load(Marshal.dump(@cache))
 
-        assert_equal 11, @cache.columns('posts').size
-        assert_equal 11, @cache.columns_hash('posts').size
-        assert @cache.data_sources('posts')
-        assert_equal 'id', @cache.primary_keys('posts')
+        assert_no_queries do
+          assert_equal 11, @cache.columns("posts").size
+          assert_equal 11, @cache.columns_hash("posts").size
+          assert @cache.data_sources("posts")
+          assert_equal "id", @cache.primary_keys("posts")
+        end
+      end
+
+      def test_data_source_exist
+        assert @cache.data_source_exists?("posts")
+        assert_not @cache.data_source_exists?("foo")
       end
 
-      def test_table_methods_deprecation
-        assert_deprecated { assert @cache.table_exists?('posts') }
-        assert_deprecated { assert @cache.tables('posts') }
-        assert_deprecated { @cache.clear_table_cache!('posts') }
+      def test_clear_data_source_cache
+        @cache.clear_data_source_cache!("posts")
       end
+
+      private
+
+        def schema_dump_path
+          "test/assets/schema_dump_5_1.yml"
+        end
     end
   end
 end
diff --git a/activerecord/test/cases/connection_adapters/type_lookup_test.rb b/activerecord/test/cases/connection_adapters/type_lookup_test.rb
index 3acbafbff4..917a04ebc3 100644
--- a/activerecord/test/cases/connection_adapters/type_lookup_test.rb
+++ b/activerecord/test/cases/connection_adapters/type_lookup_test.rb
@@ -1,110 +1,120 @@
+# frozen_string_literal: true
+
 require "cases/helper"
 
 unless current_adapter?(:PostgreSQLAdapter) # PostgreSQL does not use type strings for lookup
-module ActiveRecord
-  module ConnectionAdapters
-    class TypeLookupTest < ActiveRecord::TestCase
-      setup do
-        @connection = ActiveRecord::Base.connection
-      end
-
-      def test_boolean_types
-        assert_lookup_type :boolean, 'boolean'
-        assert_lookup_type :boolean, 'BOOLEAN'
-      end
+  module ActiveRecord
+    module ConnectionAdapters
+      class TypeLookupTest < ActiveRecord::TestCase
+        setup do
+          @connection = ActiveRecord::Base.connection
+        end
 
-      def test_string_types
-        assert_lookup_type :string, 'char'
-        assert_lookup_type :string, 'varchar'
-        assert_lookup_type :string, 'VARCHAR'
-        assert_lookup_type :string, 'varchar(255)'
-        assert_lookup_type :string, 'character varying'
-      end
+        def test_boolean_types
+          assert_lookup_type :boolean, "boolean"
+          assert_lookup_type :boolean, "BOOLEAN"
+        end
 
-      def test_binary_types
-        assert_lookup_type :binary, 'binary'
-        assert_lookup_type :binary, 'BINARY'
-        assert_lookup_type :binary, 'blob'
-        assert_lookup_type :binary, 'BLOB'
-      end
+        def test_string_types
+          assert_lookup_type :string, "char"
+          assert_lookup_type :string, "varchar"
+          assert_lookup_type :string, "VARCHAR"
+          assert_lookup_type :string, "varchar(255)"
+          assert_lookup_type :string, "character varying"
+        end
 
-      def test_text_types
-        assert_lookup_type :text, 'text'
-        assert_lookup_type :text, 'TEXT'
-        assert_lookup_type :text, 'clob'
-        assert_lookup_type :text, 'CLOB'
-      end
+        def test_binary_types
+          assert_lookup_type :binary, "binary"
+          assert_lookup_type :binary, "BINARY"
+          assert_lookup_type :binary, "blob"
+          assert_lookup_type :binary, "BLOB"
+        end
 
-      def test_date_types
-        assert_lookup_type :date, 'date'
-        assert_lookup_type :date, 'DATE'
-      end
+        def test_text_types
+          assert_lookup_type :text, "text"
+          assert_lookup_type :text, "TEXT"
+          assert_lookup_type :text, "clob"
+          assert_lookup_type :text, "CLOB"
+        end
 
-      def test_time_types
-        assert_lookup_type :time, 'time'
-        assert_lookup_type :time, 'TIME'
-      end
+        def test_date_types
+          assert_lookup_type :date, "date"
+          assert_lookup_type :date, "DATE"
+        end
 
-      def test_datetime_types
-        assert_lookup_type :datetime, 'datetime'
-        assert_lookup_type :datetime, 'DATETIME'
-        assert_lookup_type :datetime, 'timestamp'
-        assert_lookup_type :datetime, 'TIMESTAMP'
-      end
+        def test_time_types
+          assert_lookup_type :time, "time"
+          assert_lookup_type :time, "TIME"
+        end
 
-      def test_decimal_types
-        assert_lookup_type :decimal, 'decimal'
-        assert_lookup_type :decimal, 'decimal(2,8)'
-        assert_lookup_type :decimal, 'DECIMAL'
-        assert_lookup_type :decimal, 'numeric'
-        assert_lookup_type :decimal, 'numeric(2,8)'
-        assert_lookup_type :decimal, 'NUMERIC'
-        assert_lookup_type :decimal, 'number'
-        assert_lookup_type :decimal, 'number(2,8)'
-        assert_lookup_type :decimal, 'NUMBER'
-      end
+        def test_datetime_types
+          assert_lookup_type :datetime, "datetime"
+          assert_lookup_type :datetime, "DATETIME"
+          assert_lookup_type :datetime, "timestamp"
+          assert_lookup_type :datetime, "TIMESTAMP"
+        end
 
-      def test_float_types
-        assert_lookup_type :float, 'float'
-        assert_lookup_type :float, 'FLOAT'
-        assert_lookup_type :float, 'double'
-        assert_lookup_type :float, 'DOUBLE'
-      end
+        def test_decimal_types
+          assert_lookup_type :decimal, "decimal"
+          assert_lookup_type :decimal, "decimal(2,8)"
+          assert_lookup_type :decimal, "DECIMAL"
+          assert_lookup_type :decimal, "numeric"
+          assert_lookup_type :decimal, "numeric(2,8)"
+          assert_lookup_type :decimal, "NUMERIC"
+          assert_lookup_type :decimal, "number"
+          assert_lookup_type :decimal, "number(2,8)"
+          assert_lookup_type :decimal, "NUMBER"
+        end
 
-      def test_integer_types
-        assert_lookup_type :integer, 'integer'
-        assert_lookup_type :integer, 'INTEGER'
-        assert_lookup_type :integer, 'tinyint'
-        assert_lookup_type :integer, 'smallint'
-        assert_lookup_type :integer, 'bigint'
-      end
+        def test_float_types
+          assert_lookup_type :float, "float"
+          assert_lookup_type :float, "FLOAT"
+          assert_lookup_type :float, "double"
+          assert_lookup_type :float, "DOUBLE"
+        end
 
-      def test_bigint_limit
-        cast_type = @connection.type_map.lookup("bigint")
-        if current_adapter?(:OracleAdapter)
-          assert_equal 19, cast_type.limit
-        else
-          assert_equal 8, cast_type.limit
+        def test_integer_types
+          assert_lookup_type :integer, "integer"
+          assert_lookup_type :integer, "INTEGER"
+          assert_lookup_type :integer, "tinyint"
+          assert_lookup_type :integer, "smallint"
+          assert_lookup_type :integer, "bigint"
         end
-      end
 
-      def test_decimal_without_scale
-        types = %w{decimal(2) decimal(2,0) numeric(2) numeric(2,0) number(2) number(2,0)}
-        types.each do |type|
-          cast_type = @connection.type_map.lookup(type)
+        def test_bigint_limit
+          cast_type = @connection.send(:type_map).lookup("bigint")
+          if current_adapter?(:OracleAdapter)
+            assert_equal 19, cast_type.limit
+          else
+            assert_equal 8, cast_type.limit
+          end
+        end
 
-          assert_equal :decimal, cast_type.type
-          assert_equal 2, cast_type.cast(2.1)
+        def test_decimal_without_scale
+          if current_adapter?(:OracleAdapter)
+            {
+              decimal: %w{decimal(2) decimal(2,0) numeric(2) numeric(2,0)},
+              integer: %w{number(2) number(2,0)}
+            }
+          else
+            { decimal: %w{decimal(2) decimal(2,0) numeric(2) numeric(2,0) number(2) number(2,0)} }
+          end.each do |expected_type, types|
+            types.each do |type|
+              cast_type = @connection.send(:type_map).lookup(type)
+
+              assert_equal expected_type, cast_type.type
+              assert_equal 2, cast_type.cast(2.1)
+            end
+          end
         end
-      end
 
-      private
+        private
 
-      def assert_lookup_type(type, lookup)
-        cast_type = @connection.type_map.lookup(lookup)
-        assert_equal type, cast_type.type
+          def assert_lookup_type(type, lookup)
+            cast_type = @connection.send(:type_map).lookup(lookup)
+            assert_equal type, cast_type.type
+          end
       end
     end
   end
 end
-end
diff --git a/activerecord/test/cases/connection_management_test.rb b/activerecord/test/cases/connection_management_test.rb
index 1f9b6add7a..9d6ecbde78 100644
--- a/activerecord/test/cases/connection_management_test.rb
+++ b/activerecord/test/cases/connection_management_test.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require "cases/helper"
 require "rack"
 
@@ -14,7 +16,7 @@ module ActiveRecord
 
         def call(env)
           @calls << env
-          [200, {}, ['hi mom']]
+          [200, {}, ["hi mom"]]
         end
       end
 
@@ -39,7 +41,7 @@ module ActiveRecord
         _, _, body = @management.call(@env)
         bits = []
         body.each { |bit| bits << bit }
-        assert_equal ['hi mom'], bits
+        assert_equal ["hi mom"], bits
       end
 
       def test_connections_are_cleared_after_body_close
@@ -88,10 +90,10 @@ module ActiveRecord
       end
 
       test "doesn't mutate the original response" do
-        original_response = [200, {}, 'hi']
+        original_response = [200, {}, "hi"]
         app = lambda { |_| original_response }
         middleware(app).call(@env)[2]
-        assert_equal 'hi', original_response.last
+        assert_equal "hi", original_response.last
       end
 
       private
@@ -104,7 +106,7 @@ module ActiveRecord
         def middleware(app)
           lambda do |env|
             a, b, c = executor.wrap { app.call(env) }
-            [a, b, Rack::BodyProxy.new(c) { }]
+            [a, b, Rack::BodyProxy.new(c) {}]
           end
         end
     end
diff --git a/activerecord/test/cases/connection_pool_test.rb b/activerecord/test/cases/connection_pool_test.rb
index a45ee281c7..cb29c578b7 100644
--- a/activerecord/test/cases/connection_pool_test.rb
+++ b/activerecord/test/cases/connection_pool_test.rb
@@ -1,5 +1,7 @@
+# frozen_string_literal: true
+
 require "cases/helper"
-require 'concurrent/atomic/count_down_latch'
+require "concurrent/atomic/count_down_latch"
 
 module ActiveRecord
   module ConnectionAdapters
@@ -89,7 +91,7 @@ module ActiveRecord
       end
 
       def test_full_pool_exception
-        @pool.size.times { @pool.checkout }
+        @pool.size.times { assert @pool.checkout }
         assert_raises(ConnectionTimeoutError) do
           @pool.checkout
         end
@@ -151,7 +153,54 @@ module ActiveRecord
 
         assert_equal 1, active_connections(@pool).size
       ensure
-        @pool.connections.each(&:close)
+        @pool.connections.each { |conn| conn.close if conn.in_use? }
+      end
+
+      def test_flush
+        idle_conn = @pool.checkout
+        recent_conn = @pool.checkout
+        active_conn = @pool.checkout
+
+        @pool.checkin idle_conn
+        @pool.checkin recent_conn
+
+        assert_equal 3, @pool.connections.length
+
+        def idle_conn.seconds_idle
+          1000
+        end
+
+        @pool.flush(30)
+
+        assert_equal 2, @pool.connections.length
+
+        assert_equal [recent_conn, active_conn].sort_by(&:__id__), @pool.connections.sort_by(&:__id__)
+      ensure
+        @pool.checkin active_conn
+      end
+
+      def test_flush_bang
+        idle_conn = @pool.checkout
+        recent_conn = @pool.checkout
+        active_conn = @pool.checkout
+        _dead_conn = Thread.new { @pool.checkout }.join
+
+        @pool.checkin idle_conn
+        @pool.checkin recent_conn
+
+        assert_equal 4, @pool.connections.length
+
+        def idle_conn.seconds_idle
+          1000
+        end
+
+        @pool.flush!
+
+        assert_equal 1, @pool.connections.length
+
+        assert_equal [active_conn].sort_by(&:__id__), @pool.connections.sort_by(&:__id__)
+      ensure
+        @pool.checkin active_conn
       end
 
       def test_remove_connection
@@ -184,14 +233,14 @@ module ActiveRecord
 
       def test_checkout_behaviour
         pool = ConnectionPool.new ActiveRecord::Base.connection_pool.spec
-        connection = pool.connection
-        assert_not_nil connection
+        main_connection = pool.connection
+        assert_not_nil main_connection
         threads = []
         4.times do |i|
           threads << Thread.new(i) do
-            connection = pool.connection
-            assert_not_nil connection
-            connection.close
+            thread_connection = pool.connection
+            assert_not_nil thread_connection
+            thread_connection.close
           end
         end
 
@@ -203,6 +252,14 @@ module ActiveRecord
         end.join
       end
 
+      def test_checkout_order_is_lifo
+        conn1 = @pool.checkout
+        conn2 = @pool.checkout
+        @pool.checkin conn1
+        @pool.checkin conn2
+        assert_equal [conn2, conn1], 2.times.map { @pool.checkout }
+      end
+
       # The connection pool is "fair" if threads waiting for
       # connections receive them in the order in which they began
       # waiting.  This ensures that we don't timeout one HTTP request
@@ -307,14 +364,17 @@ module ActiveRecord
         end
       end
 
-      def test_automatic_reconnect=
+      def test_automatic_reconnect_restores_after_disconnect
         pool = ConnectionPool.new ActiveRecord::Base.connection_pool.spec
         assert pool.automatic_reconnect
         assert pool.connection
 
         pool.disconnect!
         assert pool.connection
+      end
 
+      def test_automatic_reconnect_can_be_disabled
+        pool = ConnectionPool.new ActiveRecord::Base.connection_pool.spec
         pool.disconnect!
         pool.automatic_reconnect = false
 
@@ -341,6 +401,22 @@ module ActiveRecord
         end
       end
 
+      class ConnectionTestModel < ActiveRecord::Base
+      end
+
+      def test_connection_notification_is_called
+        payloads = []
+        subscription = ActiveSupport::Notifications.subscribe("!connection.active_record") do |name, started, finished, unique_id, payload|
+          payloads << payload
+        end
+        ConnectionTestModel.establish_connection :arunit
+
+        assert_equal [:config, :connection_id, :spec_name], payloads[0].keys.sort
+        assert_equal "ActiveRecord::ConnectionAdapters::ConnectionPoolTest::ConnectionTestModel", payloads[0][:spec_name]
+      ensure
+        ActiveSupport::Notifications.unsubscribe(subscription) if subscription
+      end
+
       def test_pool_sets_connection_schema_cache
         connection = pool.checkout
         schema_cache = SchemaCache.new connection
@@ -383,8 +459,8 @@ module ActiveRecord
             all_threads_in_new_connection.wait
           end
         rescue Timeout::Error
-          flunk 'pool unable to establish connections concurrently or implementation has ' <<
-                'changed, this test then needs to patch a different :new_connection method'
+          flunk "pool unable to establish connections concurrently or implementation has " \
+                "changed, this test then needs to patch a different :new_connection method"
         ensure
           # clean up the threads
           all_go.count_down
@@ -393,6 +469,7 @@ module ActiveRecord
       end
 
       def test_non_bang_disconnect_and_clear_reloadable_connections_throw_exception_if_threads_dont_return_their_conns
+        Thread.report_on_exception, original_report_on_exception = false, Thread.report_on_exception if Thread.respond_to?(:report_on_exception)
         @pool.checkout_timeout = 0.001 # no need to delay test suite by waiting the whole full default timeout
         [:disconnect, :clear_reloadable_connections].each do |group_action_method|
           @pool.with_connection do |connection|
@@ -401,6 +478,8 @@ module ActiveRecord
             end
           end
         end
+      ensure
+        Thread.report_on_exception = original_report_on_exception if Thread.respond_to?(:report_on_exception)
       end
 
       def test_disconnect_and_clear_reloadable_connections_attempt_to_wait_for_threads_to_return_their_conns
@@ -425,13 +504,16 @@ module ActiveRecord
         end
       end
 
-      def test_bang_versions_of_disconnect_and_clear_reloadable_connections_if_unable_to_aquire_all_connections_proceed_anyway
+      def test_bang_versions_of_disconnect_and_clear_reloadable_connections_if_unable_to_acquire_all_connections_proceed_anyway
         @pool.checkout_timeout = 0.001 # no need to delay test suite by waiting the whole full default timeout
         [:disconnect!, :clear_reloadable_connections!].each do |group_action_method|
           @pool.with_connection do |connection|
             Thread.new { @pool.send(group_action_method) }.join
             # assert connection has been forcefully taken away from us
             assert_not @pool.active_connection?
+
+            # make a new connection for with_connection to clean up
+            @pool.connection
           end
         end
       end
@@ -440,49 +522,50 @@ module ActiveRecord
         with_single_connection_pool do |pool|
           [:disconnect, :disconnect!, :clear_reloadable_connections, :clear_reloadable_connections!].each do |group_action_method|
             conn               = pool.connection # drain the only available connection
-            second_thread_done = Concurrent::CountDownLatch.new
-
-            # create a first_thread and let it get into the FIFO queue first
-            first_thread = Thread.new do
-              pool.with_connection { second_thread_done.wait }
-            end
-
-            # wait for first_thread to get in queue
-            Thread.pass until pool.num_waiting_in_queue == 1
+            second_thread_done = Concurrent::Event.new
 
-            # create a different, later thread, that will attempt to do a "group action",
-            # but because of the group action semantics it should be able to preempt the
-            # first_thread when a connection is made available
-            second_thread = Thread.new do
-              pool.send(group_action_method)
-              second_thread_done.count_down
-            end
-
-            # wait for second_thread to get in queue
-            Thread.pass until pool.num_waiting_in_queue == 2
-
-            # return the only available connection
-            pool.checkin(conn)
-
-            # if the second_thread is not able to preempt the first_thread,
-            # they will temporarily (until either of them timeouts with ConnectionTimeoutError)
-            # deadlock and a join(2) timeout will be reached
-            failed = true unless second_thread.join(2)
-
-            #--- post test clean up start
-            second_thread_done.count_down if failed
-
-            # after `pool.disconnect()` the first thread will be left stuck in queue, no need to wait for
-            # it to timeout with ConnectionTimeoutError
-            if (group_action_method == :disconnect || group_action_method == :disconnect!) && pool.num_waiting_in_queue > 0
-              pool.with_connection {} # create a new connection in case there are threads still stuck in a queue
+            begin
+              # create a first_thread and let it get into the FIFO queue first
+              first_thread = Thread.new do
+                pool.with_connection { second_thread_done.wait }
+              end
+
+              # wait for first_thread to get in queue
+              Thread.pass until pool.num_waiting_in_queue == 1
+
+              # create a different, later thread, that will attempt to do a "group action",
+              # but because of the group action semantics it should be able to preempt the
+              # first_thread when a connection is made available
+              second_thread = Thread.new do
+                pool.send(group_action_method)
+                second_thread_done.set
+              end
+
+              # wait for second_thread to get in queue
+              Thread.pass until pool.num_waiting_in_queue == 2
+
+              # return the only available connection
+              pool.checkin(conn)
+
+              # if the second_thread is not able to preempt the first_thread,
+              # they will temporarily (until either of them timeouts with ConnectionTimeoutError)
+              # deadlock and a join(2) timeout will be reached
+              assert second_thread.join(2), "#{group_action_method} is not able to preempt other waiting threads"
+
+            ensure
+              # post test clean up
+              failed = !second_thread_done.set?
+
+              if failed
+                second_thread_done.set
+
+                first_thread.join(2)
+                second_thread.join(2)
+              end
+
+              first_thread.join(10) || raise("first_thread got stuck")
+              second_thread.join(10) || raise("second_thread got stuck")
             end
-
-            first_thread.join
-            second_thread.join
-            #--- post test clean up end
-
-            flunk "#{group_action_method} is not able to preempt other waiting threads" if failed
           end
         end
       end
@@ -504,21 +587,41 @@ module ActiveRecord
           pool.clear_reloadable_connections
 
           unless stuck_thread.join(2)
-            flunk 'clear_reloadable_connections must not let other connection waiting threads get stuck in queue'
+            flunk "clear_reloadable_connections must not let other connection waiting threads get stuck in queue"
           end
 
           assert_equal 0, pool.num_waiting_in_queue
         end
       end
 
-      private
-      def with_single_connection_pool
-        one_conn_spec = ActiveRecord::Base.connection_pool.spec.dup
-        one_conn_spec.config[:pool] = 1 # this is safe to do, because .dupped ConnectionSpecification also auto-dups its config
-        yield(pool = ConnectionPool.new(one_conn_spec))
-      ensure
-        pool.disconnect! if pool
+      def test_connection_pool_stat
+        with_single_connection_pool do |pool|
+          pool.with_connection do |connection|
+            stats = pool.stat
+            assert_equal({ size: 1, connections: 1, busy: 1, dead: 0, idle: 0, waiting: 0, checkout_timeout: 5 }, stats)
+          end
+
+          stats = pool.stat
+          assert_equal({ size: 1, connections: 1, busy: 0, dead: 0, idle: 1, waiting: 0, checkout_timeout: 5 }, stats)
+
+          Thread.new do
+            pool.checkout
+            Thread.current.kill
+          end.join
+
+          stats = pool.stat
+          assert_equal({ size: 1, connections: 1, busy: 0, dead: 1, idle: 0, waiting: 0, checkout_timeout: 5 }, stats)
+        end
       end
+
+      private
+        def with_single_connection_pool
+          one_conn_spec = ActiveRecord::Base.connection_pool.spec.dup
+          one_conn_spec.config[:pool] = 1 # this is safe to do, because .dupped ConnectionSpecification also auto-dups its config
+          yield(pool = ConnectionPool.new(one_conn_spec))
+        ensure
+          pool.disconnect! if pool
+        end
     end
   end
 end
diff --git a/activerecord/test/cases/connection_specification/resolver_test.rb b/activerecord/test/cases/connection_specification/resolver_test.rb
index b30a83d9ce..5b80f16a44 100644
--- a/activerecord/test/cases/connection_specification/resolver_test.rb
+++ b/activerecord/test/cases/connection_specification/resolver_test.rb
@@ -1,59 +1,61 @@
+# frozen_string_literal: true
+
 require "cases/helper"
 
 module ActiveRecord
   module ConnectionAdapters
     class ConnectionSpecification
       class ResolverTest < ActiveRecord::TestCase
-        def resolve(spec, config={})
+        def resolve(spec, config = {})
           Resolver.new(config).resolve(spec)
         end
 
-        def spec(spec, config={})
+        def spec(spec, config = {})
           Resolver.new(config).spec(spec)
         end
 
         def test_url_invalid_adapter
           error = assert_raises(LoadError) do
-            spec 'ridiculous://foo?encoding=utf8'
+            spec "ridiculous://foo?encoding=utf8"
           end
 
-          assert_match "Could not load 'active_record/connection_adapters/ridiculous_adapter'", error.message
+          assert_match "Could not load the 'ridiculous' Active Record adapter. Ensure that the adapter is spelled correctly in config/database.yml and that you've added the necessary adapter gem to your Gemfile.", error.message
         end
 
         # The abstract adapter is used simply to bypass the bit of code that
         # checks that the adapter file can be required in.
 
         def test_url_from_environment
-          spec = resolve :production, 'production' => 'abstract://foo?encoding=utf8'
+          spec = resolve :production, "production" => "abstract://foo?encoding=utf8"
           assert_equal({
             "adapter"  =>  "abstract",
             "host"     =>  "foo",
             "encoding" => "utf8",
-            "name"     => "production"}, spec)
+            "name"     => "production" }, spec)
         end
 
         def test_url_sub_key
-          spec = resolve :production, 'production' => {"url" => 'abstract://foo?encoding=utf8'}
+          spec = resolve :production, "production" => { "url" => "abstract://foo?encoding=utf8" }
           assert_equal({
             "adapter"  => "abstract",
             "host"     => "foo",
             "encoding" => "utf8",
-            "name"     => "production"}, spec)
+            "name"     => "production" }, spec)
         end
 
         def test_url_sub_key_merges_correctly
-          hash = {"url" => 'abstract://foo?encoding=utf8&', "adapter" => "sqlite3", "host" => "bar", "pool" => "3"}
-          spec = resolve :production, 'production' => hash
+          hash = { "url" => "abstract://foo?encoding=utf8&", "adapter" => "sqlite3", "host" => "bar", "pool" => "3" }
+          spec = resolve :production, "production" => hash
           assert_equal({
             "adapter"  => "abstract",
             "host"     => "foo",
             "encoding" => "utf8",
             "pool"     => "3",
-            "name"     => "production"}, spec)
+            "name"     => "production" }, spec)
         end
 
         def test_url_host_no_db
-          spec = resolve 'abstract://foo?encoding=utf8'
+          spec = resolve "abstract://foo?encoding=utf8"
           assert_equal({
             "adapter"  => "abstract",
             "host"     => "foo",
@@ -61,13 +63,13 @@ module ActiveRecord
         end
 
         def test_url_missing_scheme
-          spec = resolve 'foo'
+          spec = resolve "foo"
           assert_equal({
             "database" => "foo" }, spec)
         end
 
         def test_url_host_db
-          spec = resolve 'abstract://foo/bar?encoding=utf8'
+          spec = resolve "abstract://foo/bar?encoding=utf8"
           assert_equal({
             "adapter"  => "abstract",
             "database" => "bar",
@@ -76,7 +78,7 @@ module ActiveRecord
         end
 
         def test_url_port
-          spec = resolve 'abstract://foo:123?encoding=utf8'
+          spec = resolve "abstract://foo:123?encoding=utf8"
           assert_equal({
             "adapter"  => "abstract",
             "port"     => 123,
@@ -85,48 +87,48 @@ module ActiveRecord
         end
 
         def test_encoded_password
-          password = 'am@z1ng_p@ssw0rd#!'
+          password = "am@z1ng_p@ssw0rd#!"
           encoded_password = URI.encode_www_form_component(password)
           spec = resolve "abstract://foo:#{encoded_password}@localhost/bar"
           assert_equal password, spec["password"]
         end
 
         def test_url_with_authority_for_sqlite3
-          spec = resolve 'sqlite3:///foo_test'
-          assert_equal('/foo_test', spec["database"])
+          spec = resolve "sqlite3:///foo_test"
+          assert_equal("/foo_test", spec["database"])
         end
 
         def test_url_absolute_path_for_sqlite3
-          spec = resolve 'sqlite3:/foo_test'
-          assert_equal('/foo_test', spec["database"])
+          spec = resolve "sqlite3:/foo_test"
+          assert_equal("/foo_test", spec["database"])
         end
 
         def test_url_relative_path_for_sqlite3
-          spec = resolve 'sqlite3:foo_test'
-          assert_equal('foo_test', spec["database"])
+          spec = resolve "sqlite3:foo_test"
+          assert_equal("foo_test", spec["database"])
         end
 
         def test_url_memory_db_for_sqlite3
-          spec = resolve 'sqlite3::memory:'
-          assert_equal(':memory:', spec["database"])
+          spec = resolve "sqlite3::memory:"
+          assert_equal(":memory:", spec["database"])
         end
 
         def test_url_sub_key_for_sqlite3
-          spec = resolve :production, 'production' => {"url" => 'sqlite3:foo?encoding=utf8'}
+          spec = resolve :production, "production" => { "url" => "sqlite3:foo?encoding=utf8" }
           assert_equal({
             "adapter"  => "sqlite3",
             "database" => "foo",
             "encoding" => "utf8",
-            "name"     => "production"}, spec)
+            "name"     => "production" }, spec)
         end
 
         def test_spec_name_on_key_lookup
-          spec = spec(:readonly, 'readonly' => {'adapter' => 'sqlite3'})
+          spec = spec(:readonly, "readonly" => { "adapter" => "sqlite3" })
           assert_equal "readonly", spec.name
         end
 
         def test_spec_name_with_inline_config
-          spec = spec({'adapter' => 'sqlite3'})
+          spec = spec("adapter" => "sqlite3")
           assert_equal "primary", spec.name, "should default to primary id"
         end
       end
diff --git a/activerecord/test/cases/core_test.rb b/activerecord/test/cases/core_test.rb
index 3cb98832c5..356afdbd2b 100644
--- a/activerecord/test/cases/core_test.rb
+++ b/activerecord/test/cases/core_test.rb
@@ -1,8 +1,10 @@
-require 'cases/helper'
-require 'models/person'
-require 'models/topic'
-require 'pp'
-require 'active_support/core_ext/string/strip'
+# frozen_string_literal: true
+
+require "cases/helper"
+require "models/person"
+require "models/topic"
+require "pp"
+require "active_support/core_ext/string/strip"
 
 class NonExistentTable < ActiveRecord::Base; end
 
@@ -10,8 +12,8 @@ class CoreTest < ActiveRecord::TestCase
   fixtures :topics
 
   def test_inspect_class
-    assert_equal 'ActiveRecord::Base', ActiveRecord::Base.inspect
-    assert_equal 'LoosePerson(abstract)', LoosePerson.inspect
+    assert_equal "ActiveRecord::Base", ActiveRecord::Base.inspect
+    assert_equal "LoosePerson(abstract)", LoosePerson.inspect
     assert_match(/^Topic\(id: integer, title: string/, Topic.inspect)
   end
 
@@ -25,8 +27,8 @@ class CoreTest < ActiveRecord::TestCase
   end
 
   def test_inspect_limited_select_instance
-    assert_equal %(#<Topic id: 1>), Topic.all.merge!(:select => 'id', :where => 'id = 1').first.inspect
-    assert_equal %(#<Topic id: 1, title: "The First Topic">), Topic.all.merge!(:select => 'id, title', :where => 'id = 1').first.inspect
+    assert_equal %(#<Topic id: 1>), Topic.all.merge!(select: "id", where: "id = 1").first.inspect
+    assert_equal %(#<Topic id: 1, title: "The First Topic">), Topic.all.merge!(select: "id, title", where: "id = 1").first.inspect
   end
 
   def test_inspect_class_without_table
@@ -35,7 +37,7 @@ class CoreTest < ActiveRecord::TestCase
 
   def test_pretty_print_new
     topic = Topic.new
-    actual = ''
+    actual = "".dup
     PP.pp(topic, StringIO.new(actual))
     expected = <<-PRETTY.strip_heredoc
     #<Topic:0xXXXXXX
@@ -58,13 +60,13 @@ class CoreTest < ActiveRecord::TestCase
      created_at: nil,
      updated_at: nil>
     PRETTY
-    assert actual.start_with?(expected.split('XXXXXX').first)
-    assert actual.end_with?(expected.split('XXXXXX').last)
+    assert actual.start_with?(expected.split("XXXXXX").first)
+    assert actual.end_with?(expected.split("XXXXXX").last)
   end
 
   def test_pretty_print_persisted
     topic = topics(:first)
-    actual = ''
+    actual = "".dup
     PP.pp(topic, StringIO.new(actual))
     expected = <<-PRETTY.strip_heredoc
     #<Topic:0x\\w+
@@ -92,11 +94,11 @@ class CoreTest < ActiveRecord::TestCase
 
   def test_pretty_print_uninitialized
     topic = Topic.allocate
-    actual = ''
+    actual = "".dup
     PP.pp(topic, StringIO.new(actual))
     expected = "#<Topic:XXXXXX not initialized>\n"
-    assert actual.start_with?(expected.split('XXXXXX').first)
-    assert actual.end_with?(expected.split('XXXXXX').last)
+    assert actual.start_with?(expected.split("XXXXXX").first)
+    assert actual.end_with?(expected.split("XXXXXX").last)
   end
 
   def test_pretty_print_overridden_by_inspect
@@ -105,7 +107,7 @@ class CoreTest < ActiveRecord::TestCase
         "inspecting topic"
       end
     end
-    actual = ''
+    actual = "".dup
     PP.pp(subtopic.new, StringIO.new(actual))
     assert_equal "inspecting topic\n", actual
   end
diff --git a/activerecord/test/cases/counter_cache_test.rb b/activerecord/test/cases/counter_cache_test.rb
index 66b4c3f1ff..e0948f90ac 100644
--- a/activerecord/test/cases/counter_cache_test.rb
+++ b/activerecord/test/cases/counter_cache_test.rb
@@ -1,30 +1,32 @@
-require 'cases/helper'
-require 'models/topic'
-require 'models/car'
-require 'models/aircraft'
-require 'models/wheel'
-require 'models/engine'
-require 'models/reply'
-require 'models/category'
-require 'models/categorization'
-require 'models/dog'
-require 'models/dog_lover'
-require 'models/person'
-require 'models/friendship'
-require 'models/subscriber'
-require 'models/subscription'
-require 'models/book'
+# frozen_string_literal: true
+
+require "cases/helper"
+require "models/topic"
+require "models/car"
+require "models/aircraft"
+require "models/wheel"
+require "models/engine"
+require "models/reply"
+require "models/category"
+require "models/categorization"
+require "models/dog"
+require "models/dog_lover"
+require "models/person"
+require "models/friendship"
+require "models/subscriber"
+require "models/subscription"
+require "models/book"
 
 class CounterCacheTest < ActiveRecord::TestCase
   fixtures :topics, :categories, :categorizations, :cars, :dogs, :dog_lovers, :people, :friendships, :subscribers, :subscriptions, :books
 
   class ::SpecialTopic < ::Topic
-    has_many :special_replies, :foreign_key => 'parent_id'
-    has_many :lightweight_special_replies, -> { select('topics.id, topics.title') }, :foreign_key => 'parent_id', :class_name => 'SpecialReply'
+    has_many :special_replies, foreign_key: "parent_id"
+    has_many :lightweight_special_replies, -> { select("topics.id, topics.title") }, foreign_key: "parent_id", class_name: "SpecialReply"
   end
 
   class ::SpecialReply < ::Reply
-    belongs_to :special_topic, :foreign_key => 'parent_id', :counter_cache => 'replies_count'
+    belongs_to :special_topic, foreign_key: "parent_id", counter_cache: "replies_count"
   end
 
   setup do
@@ -32,13 +34,13 @@ class CounterCacheTest < ActiveRecord::TestCase
   end
 
   test "increment counter" do
-    assert_difference '@topic.reload.replies_count' do
+    assert_difference "@topic.reload.replies_count" do
       Topic.increment_counter(:replies_count, @topic.id)
     end
   end
 
   test "decrement counter" do
-    assert_difference '@topic.reload.replies_count', -1 do
+    assert_difference "@topic.reload.replies_count", -1 do
       Topic.decrement_counter(:replies_count, @topic.id)
     end
   end
@@ -48,7 +50,7 @@ class CounterCacheTest < ActiveRecord::TestCase
     Topic.increment_counter(:replies_count, @topic.id)
 
     # check that it gets reset
-    assert_difference '@topic.reload.replies_count', -1 do
+    assert_difference "@topic.reload.replies_count", -1 do
       Topic.reset_counters(@topic.id, :replies)
     end
   end
@@ -58,31 +60,31 @@ class CounterCacheTest < ActiveRecord::TestCase
     Topic.increment_counter(:replies_count, @topic.id)
 
     # check that it gets reset
-    assert_difference '@topic.reload.replies_count', -1 do
+    assert_difference "@topic.reload.replies_count", -1 do
       Topic.reset_counters(@topic.id, :replies_count)
     end
   end
 
-  test 'reset multiple counters' do
+  test "reset multiple counters" do
     Topic.update_counters @topic.id, replies_count: 1, unique_replies_count: 1
-    assert_difference ['@topic.reload.replies_count', '@topic.reload.unique_replies_count'], -1 do
+    assert_difference ["@topic.reload.replies_count", "@topic.reload.unique_replies_count"], -1 do
       Topic.reset_counters(@topic.id, :replies, :unique_replies)
     end
   end
 
   test "reset counters with string argument" do
-    Topic.increment_counter('replies_count', @topic.id)
+    Topic.increment_counter("replies_count", @topic.id)
 
-    assert_difference '@topic.reload.replies_count', -1 do
-      Topic.reset_counters(@topic.id, 'replies')
+    assert_difference "@topic.reload.replies_count", -1 do
+      Topic.reset_counters(@topic.id, "replies")
     end
   end
 
   test "reset counters with modularized and camelized classnames" do
-    special = SpecialTopic.create!(:title => 'Special')
+    special = SpecialTopic.create!(title: "Special")
     SpecialTopic.increment_counter(:replies_count, special.id)
 
-    assert_difference 'special.reload.replies_count', -1 do
+    assert_difference "special.reload.replies_count", -1 do
       SpecialTopic.reset_counters(special.id, :special_replies)
     end
   end
@@ -103,10 +105,10 @@ class CounterCacheTest < ActiveRecord::TestCase
     DogLover.increment_counter(:bred_dogs_count, david.id)
     DogLover.increment_counter(:trained_dogs_count, david.id)
 
-    assert_difference 'david.reload.bred_dogs_count', -1 do
+    assert_difference "david.reload.bred_dogs_count", -1 do
       DogLover.reset_counters(david.id, :bred_dogs)
     end
-    assert_difference 'david.reload.trained_dogs_count', -1 do
+    assert_difference "david.reload.trained_dogs_count", -1 do
       DogLover.reset_counters(david.id, :trained_dogs)
     end
   end
@@ -116,26 +118,26 @@ class CounterCacheTest < ActiveRecord::TestCase
     assert_equal 2, category.categorizations.count
     assert_nil category.categorizations_count
 
-    Category.update_counters(category.id, :categorizations_count => category.categorizations.count)
+    Category.update_counters(category.id, categorizations_count: category.categorizations.count)
     assert_equal 2, category.reload.categorizations_count
   end
 
   test "update counter for decrement" do
-    assert_difference '@topic.reload.replies_count', -3 do
-      Topic.update_counters(@topic.id, :replies_count => -3)
+    assert_difference "@topic.reload.replies_count", -3 do
+      Topic.update_counters(@topic.id, replies_count: -3)
     end
   end
 
   test "update counters of multiple records" do
     t1, t2 = topics(:first, :second)
 
-    assert_difference ['t1.reload.replies_count', 't2.reload.replies_count'], 2 do
-      Topic.update_counters([t1.id, t2.id], :replies_count => 2)
+    assert_difference ["t1.reload.replies_count", "t2.reload.replies_count"], 2 do
+      Topic.update_counters([t1.id, t2.id], replies_count: 2)
     end
   end
 
-  test 'update multiple counters' do
-    assert_difference ['@topic.reload.replies_count', '@topic.reload.unique_replies_count'], 2 do
+  test "update multiple counters" do
+    assert_difference ["@topic.reload.replies_count", "@topic.reload.unique_replies_count"], 2 do
       Topic.update_counters @topic.id, replies_count: 2, unique_replies_count: 2
     end
   end
@@ -144,7 +146,7 @@ class CounterCacheTest < ActiveRecord::TestCase
     david, joanna = dog_lovers(:david, :joanna)
     joanna = joanna # squelch a warning
 
-    assert_difference 'joanna.reload.dogs_count', -1 do
+    assert_difference "joanna.reload.dogs_count", -1 do
       david.destroy
     end
   end
@@ -157,12 +159,12 @@ class CounterCacheTest < ActiveRecord::TestCase
   end
 
   test "reset counter of has_many :through association" do
-    subscriber = subscribers('second')
-    Subscriber.reset_counters(subscriber.id, 'books')
-    Subscriber.increment_counter('books_count', subscriber.id)
+    subscriber = subscribers("second")
+    Subscriber.reset_counters(subscriber.id, "books")
+    Subscriber.increment_counter("books_count", subscriber.id)
 
-    assert_difference 'subscriber.reload.books_count', -1 do
-      Subscriber.reset_counters(subscriber.id, 'books')
+    assert_difference "subscriber.reload.books_count", -1 do
+      Subscriber.reset_counters(subscriber.id, "books")
     end
   end
 
@@ -174,10 +176,10 @@ class CounterCacheTest < ActiveRecord::TestCase
   end
 
   test "reset counter works with select declared on association" do
-    special = SpecialTopic.create!(:title => 'Special')
+    special = SpecialTopic.create!(title: "Special")
     SpecialTopic.increment_counter(:replies_count, special.id)
 
-    assert_difference 'special.reload.replies_count', -1 do
+    assert_difference "special.reload.replies_count", -1 do
       SpecialTopic.reset_counters(special.id, :lightweight_special_replies)
     end
   end
@@ -203,12 +205,163 @@ class CounterCacheTest < ActiveRecord::TestCase
   test "update counters in a polymorphic relationship" do
     aircraft = Aircraft.create!
 
-    assert_difference 'aircraft.reload.wheels_count' do
+    assert_difference "aircraft.reload.wheels_count" do
       aircraft.wheels << Wheel.create!
     end
 
-    assert_difference 'aircraft.reload.wheels_count', -1 do
+    assert_difference "aircraft.reload.wheels_count", -1 do
       aircraft.wheels.first.destroy
     end
   end
+
+  test "update counters doesn't touch timestamps by default" do
+    @topic.update_column :updated_at, 5.minutes.ago
+    previously_updated_at = @topic.updated_at
+
+    Topic.update_counters(@topic.id, replies_count: -1)
+
+    assert_equal previously_updated_at, @topic.updated_at
+  end
+
+  test "update counters doesn't touch timestamps with touch: []" do
+    @topic.update_column :updated_at, 5.minutes.ago
+    previously_updated_at = @topic.updated_at
+
+    Topic.update_counters(@topic.id, replies_count: -1, touch: [])
+
+    assert_equal previously_updated_at, @topic.updated_at
+  end
+
+  test "update counters with touch: true" do
+    assert_touching @topic, :updated_at do
+      Topic.update_counters(@topic.id, replies_count: -1, touch: true)
+    end
+  end
+
+  test "update counters of multiple records with touch: true" do
+    t1, t2 = topics(:first, :second)
+
+    assert_touching t1, :updated_at do
+      assert_difference ["t1.reload.replies_count", "t2.reload.replies_count"], 2 do
+        Topic.update_counters([t1.id, t2.id], replies_count: 2, touch: true)
+      end
+    end
+  end
+
+  test "update multiple counters with touch: true" do
+    assert_touching @topic, :updated_at do
+      Topic.update_counters(@topic.id, replies_count: 2, unique_replies_count: 2, touch: true)
+    end
+  end
+
+  test "reset counters with touch: true" do
+    assert_touching @topic, :updated_at do
+      Topic.reset_counters(@topic.id, :replies, touch: true)
+    end
+  end
+
+  test "reset multiple counters with touch: true" do
+    assert_touching @topic, :updated_at do
+      Topic.update_counters(@topic.id, replies_count: 1, unique_replies_count: 1)
+      Topic.reset_counters(@topic.id, :replies, :unique_replies, touch: true)
+    end
+  end
+
+  test "increment counters with touch: true" do
+    assert_touching @topic, :updated_at do
+      Topic.increment_counter(:replies_count, @topic.id, touch: true)
+    end
+  end
+
+  test "decrement counters with touch: true" do
+    assert_touching @topic, :updated_at do
+      Topic.decrement_counter(:replies_count, @topic.id, touch: true)
+    end
+  end
+
+  test "update counters with touch: :written_on" do
+    assert_touching @topic, :written_on do
+      Topic.update_counters(@topic.id, replies_count: -1, touch: :written_on)
+    end
+  end
+
+  test "update multiple counters with touch: :written_on" do
+    assert_touching @topic, :written_on do
+      Topic.update_counters(@topic.id, replies_count: 2, unique_replies_count: 2, touch: :written_on)
+    end
+  end
+
+  test "reset counters with touch: :written_on" do
+    assert_touching @topic, :written_on do
+      Topic.reset_counters(@topic.id, :replies, touch: :written_on)
+    end
+  end
+
+  test "reset multiple counters with touch: :written_on" do
+    assert_touching @topic, :written_on do
+      Topic.update_counters(@topic.id, replies_count: 1, unique_replies_count: 1)
+      Topic.reset_counters(@topic.id, :replies, :unique_replies, touch: :written_on)
+    end
+  end
+
+  test "increment counters with touch: :written_on" do
+    assert_touching @topic, :written_on do
+      Topic.increment_counter(:replies_count, @topic.id, touch: :written_on)
+    end
+  end
+
+  test "decrement counters with touch: :written_on" do
+    assert_touching @topic, :written_on do
+      Topic.decrement_counter(:replies_count, @topic.id, touch: :written_on)
+    end
+  end
+
+  test "update counters with touch: %i( updated_at written_on )" do
+    assert_touching @topic, :updated_at, :written_on do
+      Topic.update_counters(@topic.id, replies_count: -1, touch: %i( updated_at written_on ))
+    end
+  end
+
+  test "update multiple counters with touch: %i( updated_at written_on )" do
+    assert_touching @topic, :updated_at, :written_on do
+      Topic.update_counters(@topic.id, replies_count: 2, unique_replies_count: 2, touch: %i( updated_at written_on ))
+    end
+  end
+
+  test "reset counters with touch: %i( updated_at written_on )" do
+    assert_touching @topic, :updated_at, :written_on do
+      Topic.reset_counters(@topic.id, :replies, touch: %i( updated_at written_on ))
+    end
+  end
+
+  test "reset multiple counters with touch: %i( updated_at written_on )" do
+    assert_touching @topic, :updated_at, :written_on do
+      Topic.update_counters(@topic.id, replies_count: 1, unique_replies_count: 1)
+      Topic.reset_counters(@topic.id, :replies, :unique_replies, touch: %i( updated_at written_on ))
+    end
+  end
+
+  test "increment counters with touch: %i( updated_at written_on )" do
+    assert_touching @topic, :updated_at, :written_on do
+      Topic.increment_counter(:replies_count, @topic.id, touch: %i( updated_at written_on ))
+    end
+  end
+
+  test "decrement counters with touch: %i( updated_at written_on )" do
+    assert_touching @topic, :updated_at, :written_on do
+      Topic.decrement_counter(:replies_count, @topic.id, touch: %i( updated_at written_on ))
+    end
+  end
+
+  private
+    def assert_touching(record, *attributes)
+      record.update_columns attributes.map { |attr| [ attr, 5.minutes.ago ] }.to_h
+      touch_times = attributes.map { |attr| [ attr, record.public_send(attr) ] }.to_h
+
+      yield
+
+      touch_times.each do |attr, previous_touch_time|
+        assert_operator previous_touch_time, :<, record.reload.public_send(attr)
+      end
+    end
 end
diff --git a/activerecord/test/cases/custom_locking_test.rb b/activerecord/test/cases/custom_locking_test.rb
index 26d015bf71..f52b26e9ec 100644
--- a/activerecord/test/cases/custom_locking_test.rb
+++ b/activerecord/test/cases/custom_locking_test.rb
@@ -1,5 +1,7 @@
+# frozen_string_literal: true
+
 require "cases/helper"
-require 'models/person'
+require "models/person"
 
 module ActiveRecord
   class CustomLockingTest < ActiveRecord::TestCase
@@ -7,9 +9,9 @@ module ActiveRecord
 
     def test_custom_lock
       if current_adapter?(:Mysql2Adapter)
-        assert_match 'SHARE MODE', Person.lock('LOCK IN SHARE MODE').to_sql
+        assert_match "SHARE MODE", Person.lock("LOCK IN SHARE MODE").to_sql
         assert_sql(/LOCK IN SHARE MODE/) do
-          Person.all.merge!(:lock => 'LOCK IN SHARE MODE').find(1)
+          Person.all.merge!(lock: "LOCK IN SHARE MODE").find(1)
         end
       end
     end
diff --git a/activerecord/test/cases/database_statements_test.rb b/activerecord/test/cases/database_statements_test.rb
index 3169408ac0..1c934602ec 100644
--- a/activerecord/test/cases/database_statements_test.rb
+++ b/activerecord/test/cases/database_statements_test.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require "cases/helper"
 
 class DatabaseStatementsTest < ActiveRecord::TestCase
@@ -5,6 +7,13 @@ class DatabaseStatementsTest < ActiveRecord::TestCase
     @connection = ActiveRecord::Base.connection
   end
 
+  unless current_adapter?(:OracleAdapter)
+    def test_exec_insert
+      result = @connection.exec_insert("INSERT INTO accounts (firm_id,credit_limit) VALUES (42,5000)", nil, [])
+      assert_not_nil @connection.send(:last_inserted_id, result)
+    end
+  end
+
   def test_insert_should_return_the_inserted_id
     assert_not_nil return_the_inserted_id(method: :insert)
   end
@@ -13,22 +22,16 @@ class DatabaseStatementsTest < ActiveRecord::TestCase
     assert_not_nil return_the_inserted_id(method: :create)
   end
 
-  def test_insert_update_delete_sql_is_deprecated
-    assert_deprecated { @connection.insert_sql("INSERT INTO accounts (firm_id,credit_limit) VALUES (42,5000)") }
-    assert_deprecated { @connection.update_sql("UPDATE accounts SET credit_limit = 6000 WHERE firm_id = 42") }
-    assert_deprecated { @connection.delete_sql("DELETE FROM accounts WHERE firm_id = 42") }
-  end
-
   private
 
-  def return_the_inserted_id(method:)
-    # Oracle adapter uses prefetched primary key values from sequence and passes them to connection adapter insert method
-    if current_adapter?(:OracleAdapter)
-      sequence_name = "accounts_seq"
-      id_value = @connection.next_sequence_value(sequence_name)
-      @connection.send(method, "INSERT INTO accounts (id, firm_id,credit_limit) VALUES (accounts_seq.nextval,42,5000)", nil, :id, id_value, sequence_name)
-    else
-      @connection.send(method, "INSERT INTO accounts (firm_id,credit_limit) VALUES (42,5000)")
+    def return_the_inserted_id(method:)
+      # Oracle adapter uses prefetched primary key values from sequence and passes them to connection adapter insert method
+      if current_adapter?(:OracleAdapter)
+        sequence_name = "accounts_seq"
+        id_value = @connection.next_sequence_value(sequence_name)
+        @connection.send(method, "INSERT INTO accounts (id, firm_id,credit_limit) VALUES (accounts_seq.nextval,42,5000)", nil, :id, id_value, sequence_name)
+      else
+        @connection.send(method, "INSERT INTO accounts (firm_id,credit_limit) VALUES (42,5000)")
+      end
     end
-  end
 end
diff --git a/activerecord/test/cases/invalid_date_test.rb b/activerecord/test/cases/date_test.rb
index 426a350379..9f412cdb63 100644
--- a/activerecord/test/cases/invalid_date_test.rb
+++ b/activerecord/test/cases/date_test.rb
@@ -1,7 +1,21 @@
-require 'cases/helper'
-require 'models/topic'
+# frozen_string_literal: true
+
+require "cases/helper"
+require "models/topic"
+
+class DateTest < ActiveRecord::TestCase
+  def test_date_with_time_value
+    time_value = Time.new(2016, 05, 11, 19, 0, 0)
+    topic = Topic.create(last_read: time_value)
+    assert_equal topic, Topic.find_by(last_read: time_value)
+  end
+
+  def test_date_with_string_value
+    string_value = "2016-05-11 19:00:00"
+    topic = Topic.create(last_read: string_value)
+    assert_equal topic, Topic.find_by(last_read: string_value)
+  end
 
-class InvalidDateTest < ActiveRecord::TestCase
   def test_assign_valid_dates
     valid_dates = [[2007, 11, 30], [1993, 2, 28], [2008, 2, 29]]
 
@@ -19,7 +33,7 @@ class InvalidDateTest < ActiveRecord::TestCase
 
     invalid_dates.each do |date_src|
       assert_nothing_raised do
-        topic = Topic.new({"last_read(1i)" => date_src[0].to_s, "last_read(2i)" => date_src[1].to_s, "last_read(3i)" => date_src[2].to_s})
+        topic = Topic.new("last_read(1i)" => date_src[0].to_s, "last_read(2i)" => date_src[1].to_s, "last_read(3i)" => date_src[2].to_s)
         # Oracle DATE columns are datetime columns and Oracle adapter returns Time value
         if current_adapter?(:OracleAdapter)
           assert_equal(topic.last_read.to_date, Time.local(*date_src).to_date, "The date should be modified according to the behavior of the Time object")
diff --git a/activerecord/test/cases/date_time_precision_test.rb b/activerecord/test/cases/date_time_precision_test.rb
index f8664d83bd..51f6164138 100644
--- a/activerecord/test/cases/date_time_precision_test.rb
+++ b/activerecord/test/cases/date_time_precision_test.rb
@@ -1,88 +1,89 @@
-require 'cases/helper'
-require 'support/schema_dumping_helper'
+# frozen_string_literal: true
 
-if subsecond_precision_supported?
-class DateTimePrecisionTest < ActiveRecord::TestCase
-  include SchemaDumpingHelper
-  self.use_transactional_tests = false
+require "cases/helper"
+require "support/schema_dumping_helper"
 
-  class Foo < ActiveRecord::Base; end
+if subsecond_precision_supported?
+  class DateTimePrecisionTest < ActiveRecord::TestCase
+    include SchemaDumpingHelper
+    self.use_transactional_tests = false
 
-  setup do
-    @connection = ActiveRecord::Base.connection
-    Foo.reset_column_information
-  end
+    class Foo < ActiveRecord::Base; end
 
-  teardown do
-    @connection.drop_table :foos, if_exists: true
-  end
+    setup do
+      @connection = ActiveRecord::Base.connection
+      Foo.reset_column_information
+    end
 
-  def test_datetime_data_type_with_precision
-    @connection.create_table(:foos, force: true)
-    @connection.add_column :foos, :created_at, :datetime, precision: 0
-    @connection.add_column :foos, :updated_at, :datetime, precision: 5
-    assert_equal 0, Foo.columns_hash['created_at'].precision
-    assert_equal 5, Foo.columns_hash['updated_at'].precision
-  end
+    teardown do
+      @connection.drop_table :foos, if_exists: true
+    end
 
-  def test_timestamps_helper_with_custom_precision
-    @connection.create_table(:foos, force: true) do |t|
-      t.timestamps precision: 4
+    def test_datetime_data_type_with_precision
+      @connection.create_table(:foos, force: true)
+      @connection.add_column :foos, :created_at, :datetime, precision: 0
+      @connection.add_column :foos, :updated_at, :datetime, precision: 5
+      assert_equal 0, Foo.columns_hash["created_at"].precision
+      assert_equal 5, Foo.columns_hash["updated_at"].precision
     end
-    assert_equal 4, Foo.columns_hash['created_at'].precision
-    assert_equal 4, Foo.columns_hash['updated_at'].precision
-  end
 
-  def test_passing_precision_to_datetime_does_not_set_limit
-    @connection.create_table(:foos, force: true) do |t|
-      t.timestamps precision: 4
+    def test_timestamps_helper_with_custom_precision
+      @connection.create_table(:foos, force: true) do |t|
+        t.timestamps precision: 4
+      end
+      assert_equal 4, Foo.columns_hash["created_at"].precision
+      assert_equal 4, Foo.columns_hash["updated_at"].precision
     end
-    assert_nil Foo.columns_hash['created_at'].limit
-    assert_nil Foo.columns_hash['updated_at'].limit
-  end
 
-  def test_invalid_datetime_precision_raises_error
-    assert_raises ActiveRecord::ActiveRecordError do
+    def test_passing_precision_to_datetime_does_not_set_limit
       @connection.create_table(:foos, force: true) do |t|
-        t.timestamps precision: 7
+        t.timestamps precision: 4
       end
+      assert_nil Foo.columns_hash["created_at"].limit
+      assert_nil Foo.columns_hash["updated_at"].limit
     end
-  end
 
-  def test_formatting_datetime_according_to_precision
-    @connection.create_table(:foos, force: true) do |t|
-      t.datetime :created_at, precision: 0
-      t.datetime :updated_at, precision: 4
+    def test_invalid_datetime_precision_raises_error
+      assert_raises ActiveRecord::ActiveRecordError do
+        @connection.create_table(:foos, force: true) do |t|
+          t.timestamps precision: 7
+        end
+      end
     end
-    date = ::Time.utc(2014, 8, 17, 12, 30, 0, 999999)
-    Foo.create!(created_at: date, updated_at: date)
-    assert foo = Foo.find_by(created_at: date)
-    assert_equal 1, Foo.where(updated_at: date).count
-    assert_equal date.to_s, foo.created_at.to_s
-    assert_equal date.to_s, foo.updated_at.to_s
-    assert_equal 000000, foo.created_at.usec
-    assert_equal 999900, foo.updated_at.usec
-  end
 
-  def test_schema_dump_includes_datetime_precision
-    @connection.create_table(:foos, force: true) do |t|
-      t.timestamps precision: 6
+    def test_formatting_datetime_according_to_precision
+      @connection.create_table(:foos, force: true) do |t|
+        t.datetime :created_at, precision: 0
+        t.datetime :updated_at, precision: 4
+      end
+      date = ::Time.utc(2014, 8, 17, 12, 30, 0, 999999)
+      Foo.create!(created_at: date, updated_at: date)
+      assert foo = Foo.find_by(created_at: date)
+      assert_equal 1, Foo.where(updated_at: date).count
+      assert_equal date.to_s, foo.created_at.to_s
+      assert_equal date.to_s, foo.updated_at.to_s
+      assert_equal 000000, foo.created_at.usec
+      assert_equal 999900, foo.updated_at.usec
     end
-    output = dump_table_schema("foos")
-    assert_match %r{t\.datetime\s+"created_at",\s+precision: 6,\s+null: false$}, output
-    assert_match %r{t\.datetime\s+"updated_at",\s+precision: 6,\s+null: false$}, output
-  end
 
-  if current_adapter?(:PostgreSQLAdapter)
-    def test_datetime_precision_with_zero_should_be_dumped
+    def test_schema_dump_includes_datetime_precision
       @connection.create_table(:foos, force: true) do |t|
-        t.timestamps precision: 0
+        t.timestamps precision: 6
       end
       output = dump_table_schema("foos")
-      assert_match %r{t\.datetime\s+"created_at",\s+precision: 0,\s+null: false$}, output
-      assert_match %r{t\.datetime\s+"updated_at",\s+precision: 0,\s+null: false$}, output
+      assert_match %r{t\.datetime\s+"created_at",\s+precision: 6,\s+null: false$}, output
+      assert_match %r{t\.datetime\s+"updated_at",\s+precision: 6,\s+null: false$}, output
     end
-  end
 
-end
+    if current_adapter?(:PostgreSQLAdapter, :SQLServerAdapter)
+      def test_datetime_precision_with_zero_should_be_dumped
+        @connection.create_table(:foos, force: true) do |t|
+          t.timestamps precision: 0
+        end
+        output = dump_table_schema("foos")
+        assert_match %r{t\.datetime\s+"created_at",\s+precision: 0,\s+null: false$}, output
+        assert_match %r{t\.datetime\s+"updated_at",\s+precision: 0,\s+null: false$}, output
+      end
+    end
+  end
 end
diff --git a/activerecord/test/cases/date_time_test.rb b/activerecord/test/cases/date_time_test.rb
index 4cbff564aa..b5f35aff0e 100644
--- a/activerecord/test/cases/date_time_test.rb
+++ b/activerecord/test/cases/date_time_test.rb
@@ -1,12 +1,14 @@
+# frozen_string_literal: true
+
 require "cases/helper"
-require 'models/topic'
-require 'models/task'
+require "models/topic"
+require "models/task"
 
 class DateTimeTest < ActiveRecord::TestCase
   include InTimeZone
 
   def test_saves_both_date_and_time
-    with_env_tz 'America/New_York' do
+    with_env_tz "America/New_York" do
       with_timezone_config default: :utc do
         time_values = [1807, 2, 10, 15, 30, 45]
         # create DateTime value with local time zone offset
@@ -25,7 +27,7 @@ class DateTimeTest < ActiveRecord::TestCase
 
   def test_assign_empty_date_time
     task = Task.new
-    task.starting = ''
+    task.starting = ""
     task.ending = nil
     assert_nil task.starting
     assert_nil task.ending
@@ -34,28 +36,41 @@ class DateTimeTest < ActiveRecord::TestCase
   def test_assign_bad_date_time_with_timezone
     in_time_zone "Pacific Time (US & Canada)" do
       task = Task.new
-      task.starting = '2014-07-01T24:59:59GMT'
+      task.starting = "2014-07-01T24:59:59GMT"
       assert_nil task.starting
     end
   end
 
   def test_assign_empty_date
     topic = Topic.new
-    topic.last_read = ''
+    topic.last_read = ""
     assert_nil topic.last_read
   end
 
   def test_assign_empty_time
     topic = Topic.new
-    topic.bonus_time = ''
+    topic.bonus_time = ""
     assert_nil topic.bonus_time
   end
 
   def test_assign_in_local_timezone
-    now = DateTime.now
+    now = DateTime.civil(2017, 3, 1, 12, 0, 0)
     with_timezone_config default: :local do
       task = Task.new starting: now
       assert_equal now, task.starting
     end
   end
+
+  def test_date_time_with_string_value_with_subsecond_precision
+    skip unless subsecond_precision_supported?
+    string_value = "2017-07-04 14:19:00.5"
+    topic = Topic.create(written_on: string_value)
+    assert_equal topic, Topic.find_by(written_on: string_value)
+  end
+
+  def test_date_time_with_string_value_with_non_iso_format
+    string_value = "04/07/2017 2:19pm"
+    topic = Topic.create(written_on: string_value)
+    assert_equal topic, Topic.find_by(written_on: string_value)
+  end
 end
diff --git a/activerecord/test/cases/defaults_test.rb b/activerecord/test/cases/defaults_test.rb
index 067513e24c..3d11b573f1 100644
--- a/activerecord/test/cases/defaults_test.rb
+++ b/activerecord/test/cases/defaults_test.rb
@@ -1,7 +1,9 @@
+# frozen_string_literal: true
+
 require "cases/helper"
-require 'support/schema_dumping_helper'
-require 'models/default'
-require 'models/entrant'
+require "support/schema_dumping_helper"
+require "models/default"
+require "models/entrant"
 
 class DefaultTest < ActiveRecord::TestCase
   def test_nil_defaults_for_not_null_columns
@@ -51,7 +53,7 @@ class DefaultNumbersTest < ActiveRecord::TestCase
 
   def test_default_decimal_number
     record = DefaultNumber.new
-    assert_equal BigDecimal.new("2.78"), record.decimal_number
+    assert_equal BigDecimal("2.78"), record.decimal_number
     assert_equal "2.78", record.decimal_number_before_type_cast
   end
 end
@@ -87,9 +89,14 @@ if current_adapter?(:PostgreSQLAdapter)
 
     test "schema dump includes default expression" do
       output = dump_table_schema("defaults")
-      assert_match %r/t\.date\s+"modified_date",\s+default: -> { "\('now'::text\)::date" }/, output
+      if ActiveRecord::Base.connection.postgresql_version >= 100000
+        assert_match %r/t\.date\s+"modified_date",\s+default: -> { "CURRENT_DATE" }/, output
+        assert_match %r/t\.datetime\s+"modified_time",\s+default: -> { "CURRENT_TIMESTAMP" }/, output
+      else
+        assert_match %r/t\.date\s+"modified_date",\s+default: -> { "\('now'::text\)::date" }/, output
+        assert_match %r/t\.datetime\s+"modified_time",\s+default: -> { "now\(\)" }/, output
+      end
       assert_match %r/t\.date\s+"modified_date_function",\s+default: -> { "now\(\)" }/, output
-      assert_match %r/t\.datetime\s+"modified_time",\s+default: -> { "now\(\)" }/, output
       assert_match %r/t\.datetime\s+"modified_time_function",\s+default: -> { "now\(\)" }/, output
     end
   end
@@ -99,12 +106,22 @@ if current_adapter?(:Mysql2Adapter)
   class MysqlDefaultExpressionTest < ActiveRecord::TestCase
     include SchemaDumpingHelper
 
-    if ActiveRecord::Base.connection.version >= '5.6.0'
-      test "schema dump includes default expression" do
+    if ActiveRecord::Base.connection.version >= "5.6.0"
+      test "schema dump datetime includes default expression" do
         output = dump_table_schema("datetime_defaults")
         assert_match %r/t\.datetime\s+"modified_datetime",\s+default: -> { "CURRENT_TIMESTAMP" }/, output
       end
     end
+
+    test "schema dump timestamp includes default expression" do
+      output = dump_table_schema("timestamp_defaults")
+      assert_match %r/t\.timestamp\s+"modified_timestamp",\s+default: -> { "CURRENT_TIMESTAMP" }/, output
+    end
+
+    test "schema dump timestamp without default expression" do
+      output = dump_table_schema("timestamp_defaults")
+      assert_match %r/t\.timestamp\s+"nullable_timestamp"$/, output
+    end
   end
 
   class DefaultsTestWithoutTransactionalFixtures < ActiveRecord::TestCase
@@ -127,92 +144,66 @@ if current_adapter?(:Mysql2Adapter)
       ActiveRecord::Base.establish_connection connection
     end
 
-    # MySQL cannot have defaults on text/blob columns. It reports the
-    # default value as null.
+    # Strict mode controls how MySQL handles invalid or missing values
+    # in data-change statements such as INSERT or UPDATE. A value can be
+    # invalid for several reasons. For example, it might have the wrong
+    # data type for the column, or it might be out of range. A value is
+    # missing when a new row to be inserted does not contain a value for
+    # a non-NULL column that has no explicit DEFAULT clause in its definition.
+    # (For a NULL column, NULL is inserted if the value is missing.)
     #
-    # Despite this, in non-strict mode, MySQL will use an empty string
-    # as the default value of the field, if no other value is
-    # specified.
+    # If strict mode is not in effect, MySQL inserts adjusted values for
+    # invalid or missing values and produces warnings. In strict mode,
+    # you can produce this behavior by using INSERT IGNORE or UPDATE IGNORE.
     #
-    # Therefore, in non-strict mode, we want column.default to report
-    # an empty string as its default, to be consistent with that.
-    #
-    # In strict mode, column.default should be nil.
-    def test_mysql_text_not_null_defaults_non_strict
+    # https://dev.mysql.com/doc/refman/5.7/en/sql-mode.html#sql-mode-strict
+    def test_mysql_not_null_defaults_non_strict
       using_strict(false) do
-        with_text_blob_not_null_table do |klass|
+        with_mysql_not_null_table do |klass|
           record = klass.new
-          assert_equal '', record.non_null_blob
-          assert_equal '', record.non_null_text
-
-          assert_nil record.null_blob
-          assert_nil record.null_text
+          assert_nil record.non_null_integer
+          assert_nil record.non_null_string
+          assert_nil record.non_null_text
+          assert_nil record.non_null_blob
 
           record.save!
           record.reload
 
-          assert_equal '', record.non_null_text
-          assert_equal '', record.non_null_blob
-
-          assert_nil record.null_text
-          assert_nil record.null_blob
+          assert_equal 0,  record.non_null_integer
+          assert_equal "", record.non_null_string
+          assert_equal "", record.non_null_text
+          assert_equal "", record.non_null_blob
         end
       end
     end
 
-    def test_mysql_text_not_null_defaults_strict
+    def test_mysql_not_null_defaults_strict
       using_strict(true) do
-        with_text_blob_not_null_table do |klass|
+        with_mysql_not_null_table do |klass|
           record = klass.new
-          assert_nil record.non_null_blob
+          assert_nil record.non_null_integer
+          assert_nil record.non_null_string
           assert_nil record.non_null_text
-          assert_nil record.null_blob
-          assert_nil record.null_text
+          assert_nil record.non_null_blob
 
-          assert_raises(ActiveRecord::StatementInvalid) { klass.create }
+          assert_raises(ActiveRecord::NotNullViolation) { klass.create }
         end
       end
     end
 
-    def with_text_blob_not_null_table
+    def with_mysql_not_null_table
       klass = Class.new(ActiveRecord::Base)
-      klass.table_name = 'test_mysql_text_not_null_defaults'
+      klass.table_name = "test_mysql_not_null_defaults"
       klass.connection.create_table klass.table_name do |t|
-        t.column :non_null_text, :text, :null => false
-        t.column :non_null_blob, :blob, :null => false
-        t.column :null_text, :text, :null => true
-        t.column :null_blob, :blob, :null => true
+        t.integer :non_null_integer, null: false
+        t.string  :non_null_string,  null: false
+        t.text    :non_null_text,    null: false
+        t.blob    :non_null_blob,    null: false
       end
 
       yield klass
     ensure
       klass.connection.drop_table(klass.table_name) rescue nil
     end
-
-    # MySQL uses an implicit default 0 rather than NULL unless in strict mode.
-    # We use an implicit NULL so schema.rb is compatible with other databases.
-    def test_mysql_integer_not_null_defaults
-      klass = Class.new(ActiveRecord::Base)
-      klass.table_name = 'test_integer_not_null_default_zero'
-      klass.connection.create_table klass.table_name do |t|
-        t.column :zero, :integer, :null => false, :default => 0
-        t.column :omit, :integer, :null => false
-      end
-
-      assert_equal '0', klass.columns_hash['zero'].default
-      assert !klass.columns_hash['zero'].null
-      assert_equal nil, klass.columns_hash['omit'].default
-      assert !klass.columns_hash['omit'].null
-
-      assert_raise(ActiveRecord::StatementInvalid) { klass.create! }
-
-      assert_nothing_raised do
-        instance = klass.create!(:omit => 1)
-        assert_equal 0, instance.zero
-        assert_equal 1, instance.omit
-      end
-    ensure
-      klass.connection.drop_table(klass.table_name) rescue nil
-    end
   end
 end
diff --git a/activerecord/test/cases/dirty_test.rb b/activerecord/test/cases/dirty_test.rb
index f9794518c7..d4408776d3 100644
--- a/activerecord/test/cases/dirty_test.rb
+++ b/activerecord/test/cases/dirty_test.rb
@@ -1,20 +1,19 @@
-require 'cases/helper'
-require 'models/topic'    # For booleans
-require 'models/pirate'   # For timestamps
-require 'models/parrot'
-require 'models/person'   # For optimistic locking
-require 'models/aircraft'
-
-class NumericData < ActiveRecord::Base
-  self.table_name = 'numeric_data'
-end
+# frozen_string_literal: true
+
+require "cases/helper"
+require "models/topic"    # For booleans
+require "models/pirate"   # For timestamps
+require "models/parrot"
+require "models/person"   # For optimistic locking
+require "models/aircraft"
+require "models/numeric_data"
 
 class DirtyTest < ActiveRecord::TestCase
   include InTimeZone
 
   # Dummy to force column loads so query counts are clean.
   def setup
-    Person.create :first_name => 'foo'
+    Person.create first_name: "foo"
   end
 
   def test_attribute_changes
@@ -24,10 +23,10 @@ class DirtyTest < ActiveRecord::TestCase
     assert_equal false, pirate.non_validated_parrot_id_changed?
 
     # Change catchphrase.
-    pirate.catchphrase = 'arrr'
+    pirate.catchphrase = "arrr"
     assert pirate.catchphrase_changed?
     assert_nil pirate.catchphrase_was
-    assert_equal [nil, 'arrr'], pirate.catchphrase_change
+    assert_equal [nil, "arrr"], pirate.catchphrase_change
 
     # Saved - no changes.
     pirate.save!
@@ -35,15 +34,15 @@ class DirtyTest < ActiveRecord::TestCase
     assert_nil pirate.catchphrase_change
 
     # Same value - no changes.
-    pirate.catchphrase = 'arrr'
+    pirate.catchphrase = "arrr"
     assert !pirate.catchphrase_changed?
     assert_nil pirate.catchphrase_change
   end
 
   def test_time_attributes_changes_with_time_zone
-    in_time_zone 'Paris' do
+    in_time_zone "Paris" do
       target = Class.new(ActiveRecord::Base)
-      target.table_name = 'pirates'
+      target.table_name = "pirates"
 
       # New record - no changes.
       pirate = target.new
@@ -51,7 +50,7 @@ class DirtyTest < ActiveRecord::TestCase
       assert_nil pirate.created_on_change
 
       # Saved - no changes.
-      pirate.catchphrase = 'arrrr, time zone!!'
+      pirate.catchphrase = "arrrr, time zone!!"
       pirate.save!
       assert !pirate.created_on_changed?
       assert_nil pirate.created_on_change
@@ -68,9 +67,9 @@ class DirtyTest < ActiveRecord::TestCase
   end
 
   def test_setting_time_attributes_with_time_zone_field_to_itself_should_not_be_marked_as_a_change
-    in_time_zone 'Paris' do
+    in_time_zone "Paris" do
       target = Class.new(ActiveRecord::Base)
-      target.table_name = 'pirates'
+      target.table_name = "pirates"
 
       pirate = target.create!
       pirate.created_on = pirate.created_on
@@ -79,9 +78,9 @@ class DirtyTest < ActiveRecord::TestCase
   end
 
   def test_time_attributes_changes_without_time_zone_by_skip
-    in_time_zone 'Paris' do
+    in_time_zone "Paris" do
       target = Class.new(ActiveRecord::Base)
-      target.table_name = 'pirates'
+      target.table_name = "pirates"
 
       target.skip_time_zone_conversion_for_attributes = [:created_on]
 
@@ -91,7 +90,7 @@ class DirtyTest < ActiveRecord::TestCase
       assert_nil pirate.created_on_change
 
       # Saved - no changes.
-      pirate.catchphrase = 'arrrr, time zone!!'
+      pirate.catchphrase = "arrrr, time zone!!"
       pirate.save!
       assert !pirate.created_on_changed?
       assert_nil pirate.created_on_change
@@ -110,7 +109,7 @@ class DirtyTest < ActiveRecord::TestCase
   def test_time_attributes_changes_without_time_zone
     with_timezone_config aware_attributes: false do
       target = Class.new(ActiveRecord::Base)
-      target.table_name = 'pirates'
+      target.table_name = "pirates"
 
       # New record - no changes.
       pirate = target.new
@@ -118,7 +117,7 @@ class DirtyTest < ActiveRecord::TestCase
       assert_nil pirate.created_on_change
 
       # Saved - no changes.
-      pirate.catchphrase = 'arrrr, time zone!!'
+      pirate.catchphrase = "arrrr, time zone!!"
       pirate.save!
       assert !pirate.created_on_changed?
       assert_nil pirate.created_on_change
@@ -134,7 +133,6 @@ class DirtyTest < ActiveRecord::TestCase
     end
   end
 
-
   def test_aliased_attribute_changes
     # the actual attribute here is name, title is an
     # alias setup via alias_attribute
@@ -142,15 +140,15 @@ class DirtyTest < ActiveRecord::TestCase
     assert !parrot.title_changed?
     assert_nil parrot.title_change
 
-    parrot.name = 'Sam'
+    parrot.name = "Sam"
     assert parrot.title_changed?
     assert_nil parrot.title_was
     assert_equal parrot.name_change, parrot.title_change
   end
 
   def test_restore_attribute!
-    pirate = Pirate.create!(:catchphrase => 'Yar!')
-    pirate.catchphrase = 'Ahoy!'
+    pirate = Pirate.create!(catchphrase: "Yar!")
+    pirate.catchphrase = "Ahoy!"
 
     pirate.restore_catchphrase!
     assert_equal "Yar!", pirate.catchphrase
@@ -189,9 +187,9 @@ class DirtyTest < ActiveRecord::TestCase
   end
 
   def test_nullable_datetime_not_marked_as_changed_if_new_value_is_blank
-    in_time_zone 'Edinburgh' do
+    in_time_zone "Edinburgh" do
       target = Class.new(ActiveRecord::Base)
-      target.table_name = 'topics'
+      target.table_name = "topics"
 
       topic = target.create
       assert_nil topic.written_on
@@ -207,19 +205,19 @@ class DirtyTest < ActiveRecord::TestCase
   def test_integer_zero_to_string_zero_not_marked_as_changed
     pirate = Pirate.new
     pirate.parrot_id = 0
-    pirate.catchphrase = 'arrr'
+    pirate.catchphrase = "arrr"
     assert pirate.save!
 
     assert !pirate.changed?
 
-    pirate.parrot_id = '0'
+    pirate.parrot_id = "0"
     assert !pirate.changed?
   end
 
   def test_integer_zero_to_integer_zero_not_marked_as_changed
     pirate = Pirate.new
     pirate.parrot_id = 0
-    pirate.catchphrase = 'arrr'
+    pirate.catchphrase = "arrr"
     assert pirate.save!
 
     assert !pirate.changed?
@@ -229,18 +227,18 @@ class DirtyTest < ActiveRecord::TestCase
   end
 
   def test_float_zero_to_string_zero_not_marked_as_changed
-    data = NumericData.new :temperature => 0.0
+    data = NumericData.new temperature: 0.0
     data.save!
 
     assert_not data.changed?
 
-    data.temperature = '0'
+    data.temperature = "0"
     assert_empty data.changes
 
-    data.temperature = '0.0'
+    data.temperature = "0.0"
     assert_empty data.changes
 
-    data.temperature = '0.00'
+    data.temperature = "0.00"
     assert_empty data.changes
   end
 
@@ -252,7 +250,7 @@ class DirtyTest < ActiveRecord::TestCase
 
     # check the change from 1 to ''
     pirate = Pirate.find_by_catchphrase("Yarrrr, me hearties")
-    pirate.parrot_id = ''
+    pirate.parrot_id = ""
     assert pirate.parrot_id_changed?
     assert_equal([1, nil], pirate.parrot_id_change)
     pirate.save
@@ -266,7 +264,7 @@ class DirtyTest < ActiveRecord::TestCase
 
     # check the change from 0 to ''
     pirate = Pirate.find_by_catchphrase("Yarrrr, me hearties")
-    pirate.parrot_id = ''
+    pirate.parrot_id = ""
     assert pirate.parrot_id_changed?
     assert_equal([0, nil], pirate.parrot_id_change)
   end
@@ -277,11 +275,11 @@ class DirtyTest < ActiveRecord::TestCase
     assert_equal [], pirate.changed
     assert_equal Hash.new, pirate.changes
 
-    pirate.catchphrase = 'arrr'
+    pirate.catchphrase = "arrr"
     assert pirate.changed?
     assert_nil pirate.catchphrase_was
     assert_equal %w(catchphrase), pirate.changed
-    assert_equal({'catchphrase' => [nil, 'arrr']}, pirate.changes)
+    assert_equal({ "catchphrase" => [nil, "arrr"] }, pirate.changes)
 
     pirate.save
     assert !pirate.changed?
@@ -290,21 +288,27 @@ class DirtyTest < ActiveRecord::TestCase
   end
 
   def test_attribute_will_change!
-    pirate = Pirate.create!(:catchphrase => 'arr')
+    pirate = Pirate.create!(catchphrase: "arr")
 
     assert !pirate.catchphrase_changed?
     assert pirate.catchphrase_will_change!
     assert pirate.catchphrase_changed?
-    assert_equal ['arr', 'arr'], pirate.catchphrase_change
+    assert_equal ["arr", "arr"], pirate.catchphrase_change
 
-    pirate.catchphrase << ' matey!'
+    pirate.catchphrase << " matey!"
     assert pirate.catchphrase_changed?
-    assert_equal ['arr', 'arr matey!'], pirate.catchphrase_change
+    assert_equal ["arr", "arr matey!"], pirate.catchphrase_change
+  end
+
+  def test_virtual_attribute_will_change
+    parrot = Parrot.create!(name: "Ruby")
+    parrot.send(:attribute_will_change!, :cancel_save_from_callback)
+    assert parrot.has_changes_to_save?
   end
 
   def test_association_assignment_changes_foreign_key
-    pirate = Pirate.create!(:catchphrase => 'jarl')
-    pirate.parrot = Parrot.create!(:name => 'Lorre')
+    pirate = Pirate.create!(catchphrase: "jarl")
+    pirate.parrot = Parrot.create!(name: "Lorre")
     assert pirate.changed?
     assert_equal %w(parrot_id), pirate.changed
   end
@@ -315,7 +319,7 @@ class DirtyTest < ActiveRecord::TestCase
     assert !topic.approved_changed?
 
     # Coming from web form.
-    params = {:topic => {:approved => 1}}
+    params = { topic: { approved: 1 } }
     # In the controller.
     topic.attributes = params[:topic]
     assert topic.approved?
@@ -323,37 +327,38 @@ class DirtyTest < ActiveRecord::TestCase
   end
 
   def test_partial_update
-    pirate = Pirate.new(:catchphrase => 'foo')
+    pirate = Pirate.new(catchphrase: "foo")
     old_updated_on = 1.hour.ago.beginning_of_day
 
     with_partial_writes Pirate, false do
       assert_queries(2) { 2.times { pirate.save! } }
-      Pirate.where(id: pirate.id).update_all(:updated_on => old_updated_on)
+      Pirate.where(id: pirate.id).update_all(updated_on: old_updated_on)
     end
 
     with_partial_writes Pirate, true do
       assert_queries(0) { 2.times { pirate.save! } }
       assert_equal old_updated_on, pirate.reload.updated_on
 
-      assert_queries(1) { pirate.catchphrase = 'bar'; pirate.save! }
+      assert_queries(1) { pirate.catchphrase = "bar"; pirate.save! }
       assert_not_equal old_updated_on, pirate.reload.updated_on
     end
   end
 
   def test_partial_update_with_optimistic_locking
-    person = Person.new(:first_name => 'foo')
-    old_lock_version = 1
+    person = Person.new(first_name: "foo")
 
     with_partial_writes Person, false do
       assert_queries(2) { 2.times { person.save! } }
-      Person.where(id: person.id).update_all(:first_name => 'baz')
+      Person.where(id: person.id).update_all(first_name: "baz")
     end
 
+    old_lock_version = person.lock_version
+
     with_partial_writes Person, true do
       assert_queries(0) { 2.times { person.save! } }
       assert_equal old_lock_version, person.reload.lock_version
 
-      assert_queries(1) { person.first_name = 'bar'; person.save! }
+      assert_queries(1) { person.first_name = "bar"; person.save! }
       assert_not_equal old_lock_version, person.reload.lock_version
     end
   end
@@ -371,7 +376,7 @@ class DirtyTest < ActiveRecord::TestCase
   end
 
   def test_reload_should_clear_changed_attributes
-    pirate = Pirate.create!(:catchphrase => "shiver me timbers")
+    pirate = Pirate.create!(catchphrase: "shiver me timbers")
     pirate.catchphrase = "*hic*"
     assert pirate.changed?
     pirate.reload
@@ -379,7 +384,7 @@ class DirtyTest < ActiveRecord::TestCase
   end
 
   def test_dup_objects_should_not_copy_dirty_flag_from_creator
-    pirate = Pirate.create!(:catchphrase => "shiver me timbers")
+    pirate = Pirate.create!(catchphrase: "shiver me timbers")
     pirate_dup = pirate.dup
     pirate_dup.restore_catchphrase!
     pirate.catchphrase = "I love Rum"
@@ -389,7 +394,7 @@ class DirtyTest < ActiveRecord::TestCase
 
   def test_reverted_changes_are_not_dirty
     phrase = "shiver me timbers"
-    pirate = Pirate.create!(:catchphrase => phrase)
+    pirate = Pirate.create!(catchphrase: phrase)
     pirate.catchphrase = "*hic*"
     assert pirate.changed?
     pirate.catchphrase = phrase
@@ -398,7 +403,7 @@ class DirtyTest < ActiveRecord::TestCase
 
   def test_reverted_changes_are_not_dirty_after_multiple_changes
     phrase = "shiver me timbers"
-    pirate = Pirate.create!(:catchphrase => phrase)
+    pirate = Pirate.create!(catchphrase: phrase)
     10.times do |i|
       pirate.catchphrase = "*hic*" * i
       assert pirate.changed?
@@ -408,9 +413,8 @@ class DirtyTest < ActiveRecord::TestCase
     assert !pirate.changed?
   end
 
-
   def test_reverted_changes_are_not_dirty_going_from_nil_to_value_and_back
-    pirate = Pirate.create!(:catchphrase => "Yar!")
+    pirate = Pirate.create!(catchphrase: "Yar!")
 
     pirate.parrot_id = 1
     assert pirate.changed?
@@ -425,7 +429,7 @@ class DirtyTest < ActiveRecord::TestCase
 
   def test_save_should_store_serialized_attributes_even_with_partial_writes
     with_partial_writes(Topic) do
-      topic = Topic.create!(:content => {:a => "a"})
+      topic = Topic.create!(content: { a: "a" })
 
       assert_not topic.changed?
 
@@ -446,27 +450,26 @@ class DirtyTest < ActiveRecord::TestCase
 
   def test_save_always_should_update_timestamps_when_serialized_attributes_are_present
     with_partial_writes(Topic) do
-      topic = Topic.create!(:content => {:a => "a"})
+      topic = Topic.create!(content: { a: "a" })
       topic.save!
 
       updated_at = topic.updated_at
       travel(1.second) do
-        topic.content[:hello] = 'world'
+        topic.content[:hello] = "world"
         topic.save!
       end
 
       assert_not_equal updated_at, topic.updated_at
-      assert_equal 'world', topic.content[:hello]
+      assert_equal "world", topic.content[:hello]
     end
   end
 
   def test_save_should_not_save_serialized_attribute_with_partial_writes_if_not_present
     with_partial_writes(Topic) do
-      Topic.create!(:author_name => 'Bill', :content => {:a => "a"})
-      topic = Topic.select('id, author_name').first
-      topic.update_columns author_name: 'John'
-      topic = Topic.first
-      assert_not_nil topic.content
+      topic = Topic.create!(author_name: "Bill", content: { a: "a" })
+      topic = Topic.select("id, author_name").find(topic.id)
+      topic.update_columns author_name: "John"
+      assert_not_nil topic.reload.content
     end
   end
 
@@ -479,13 +482,13 @@ class DirtyTest < ActiveRecord::TestCase
     pirate.save!
 
     assert_equal 4, pirate.previous_changes.size
-    assert_equal [nil, "arrr"], pirate.previous_changes['catchphrase']
-    assert_equal [nil, pirate.id], pirate.previous_changes['id']
-    assert_nil pirate.previous_changes['updated_on'][0]
-    assert_not_nil pirate.previous_changes['updated_on'][1]
-    assert_nil pirate.previous_changes['created_on'][0]
-    assert_not_nil pirate.previous_changes['created_on'][1]
-    assert !pirate.previous_changes.key?('parrot_id')
+    assert_equal [nil, "arrr"], pirate.previous_changes["catchphrase"]
+    assert_equal [nil, pirate.id], pirate.previous_changes["id"]
+    assert_nil pirate.previous_changes["updated_on"][0]
+    assert_not_nil pirate.previous_changes["updated_on"][1]
+    assert_nil pirate.previous_changes["created_on"][0]
+    assert_not_nil pirate.previous_changes["created_on"][1]
+    assert !pirate.previous_changes.key?("parrot_id")
 
     # original values should be in previous_changes
     pirate = Pirate.new
@@ -495,11 +498,11 @@ class DirtyTest < ActiveRecord::TestCase
     pirate.save
 
     assert_equal 4, pirate.previous_changes.size
-    assert_equal [nil, "arrr"], pirate.previous_changes['catchphrase']
-    assert_equal [nil, pirate.id], pirate.previous_changes['id']
-    assert pirate.previous_changes.include?('updated_on')
-    assert pirate.previous_changes.include?('created_on')
-    assert !pirate.previous_changes.key?('parrot_id')
+    assert_equal [nil, "arrr"], pirate.previous_changes["catchphrase"]
+    assert_equal [nil, pirate.id], pirate.previous_changes["id"]
+    assert_includes pirate.previous_changes, "updated_on"
+    assert_includes pirate.previous_changes, "created_on"
+    assert !pirate.previous_changes.key?("parrot_id")
 
     pirate.catchphrase = "Yar!!"
     pirate.reload
@@ -513,11 +516,11 @@ class DirtyTest < ActiveRecord::TestCase
     pirate.save!
 
     assert_equal 2, pirate.previous_changes.size
-    assert_equal ["arrr", "Me Maties!"], pirate.previous_changes['catchphrase']
-    assert_not_nil pirate.previous_changes['updated_on'][0]
-    assert_not_nil pirate.previous_changes['updated_on'][1]
-    assert !pirate.previous_changes.key?('parrot_id')
-    assert !pirate.previous_changes.key?('created_on')
+    assert_equal ["arrr", "Me Maties!"], pirate.previous_changes["catchphrase"]
+    assert_not_nil pirate.previous_changes["updated_on"][0]
+    assert_not_nil pirate.previous_changes["updated_on"][1]
+    assert !pirate.previous_changes.key?("parrot_id")
+    assert !pirate.previous_changes.key?("created_on")
 
     pirate = Pirate.find_by_catchphrase("Me Maties!")
 
@@ -527,11 +530,11 @@ class DirtyTest < ActiveRecord::TestCase
     pirate.save
 
     assert_equal 2, pirate.previous_changes.size
-    assert_equal ["Me Maties!", "Thar She Blows!"], pirate.previous_changes['catchphrase']
-    assert_not_nil pirate.previous_changes['updated_on'][0]
-    assert_not_nil pirate.previous_changes['updated_on'][1]
-    assert !pirate.previous_changes.key?('parrot_id')
-    assert !pirate.previous_changes.key?('created_on')
+    assert_equal ["Me Maties!", "Thar She Blows!"], pirate.previous_changes["catchphrase"]
+    assert_not_nil pirate.previous_changes["updated_on"][0]
+    assert_not_nil pirate.previous_changes["updated_on"][1]
+    assert !pirate.previous_changes.key?("parrot_id")
+    assert !pirate.previous_changes.key?("created_on")
 
     travel(1.second)
 
@@ -539,11 +542,11 @@ class DirtyTest < ActiveRecord::TestCase
     pirate.update(catchphrase: "Ahoy!")
 
     assert_equal 2, pirate.previous_changes.size
-    assert_equal ["Thar She Blows!", "Ahoy!"], pirate.previous_changes['catchphrase']
-    assert_not_nil pirate.previous_changes['updated_on'][0]
-    assert_not_nil pirate.previous_changes['updated_on'][1]
-    assert !pirate.previous_changes.key?('parrot_id')
-    assert !pirate.previous_changes.key?('created_on')
+    assert_equal ["Thar She Blows!", "Ahoy!"], pirate.previous_changes["catchphrase"]
+    assert_not_nil pirate.previous_changes["updated_on"][0]
+    assert_not_nil pirate.previous_changes["updated_on"][1]
+    assert !pirate.previous_changes.key?("parrot_id")
+    assert !pirate.previous_changes.key?("created_on")
 
     travel(1.second)
 
@@ -551,49 +554,48 @@ class DirtyTest < ActiveRecord::TestCase
     pirate.update_attribute(:catchphrase, "Ninjas suck!")
 
     assert_equal 2, pirate.previous_changes.size
-    assert_equal ["Ahoy!", "Ninjas suck!"], pirate.previous_changes['catchphrase']
-    assert_not_nil pirate.previous_changes['updated_on'][0]
-    assert_not_nil pirate.previous_changes['updated_on'][1]
-    assert !pirate.previous_changes.key?('parrot_id')
-    assert !pirate.previous_changes.key?('created_on')
+    assert_equal ["Ahoy!", "Ninjas suck!"], pirate.previous_changes["catchphrase"]
+    assert_not_nil pirate.previous_changes["updated_on"][0]
+    assert_not_nil pirate.previous_changes["updated_on"][1]
+    assert !pirate.previous_changes.key?("parrot_id")
+    assert !pirate.previous_changes.key?("created_on")
   ensure
     travel_back
   end
 
-  if ActiveRecord::Base.connection.supports_migrations?
-    class Testings < ActiveRecord::Base; end
-    def test_field_named_field
-      ActiveRecord::Base.connection.create_table :testings do |t|
-        t.string :field
-      end
-      assert_nothing_raised do
-        Testings.new.attributes
-      end
-    ensure
-      ActiveRecord::Base.connection.drop_table :testings rescue nil
+  class Testings < ActiveRecord::Base; end
+  def test_field_named_field
+    ActiveRecord::Base.connection.create_table :testings do |t|
+      t.string :field
+    end
+    assert_nothing_raised do
+      Testings.new.attributes
     end
+  ensure
+    ActiveRecord::Base.connection.drop_table :testings rescue nil
+    ActiveRecord::Base.clear_cache!
   end
 
   def test_datetime_attribute_can_be_updated_with_fractional_seconds
     skip "Fractional seconds are not supported" unless subsecond_precision_supported?
-    in_time_zone 'Paris' do
+    in_time_zone "Paris" do
       target = Class.new(ActiveRecord::Base)
-      target.table_name = 'topics'
+      target.table_name = "topics"
 
-      written_on = Time.utc(2012, 12, 1, 12, 0, 0).in_time_zone('Paris')
+      written_on = Time.utc(2012, 12, 1, 12, 0, 0).in_time_zone("Paris")
 
-      topic = target.create(:written_on => written_on)
+      topic = target.create(written_on: written_on)
       topic.written_on += 0.3
 
-      assert topic.written_on_changed?, 'Fractional second update not detected'
+      assert topic.written_on_changed?, "Fractional second update not detected"
     end
   end
 
   def test_datetime_attribute_doesnt_change_if_zone_is_modified_in_string
-    time_in_paris = Time.utc(2014, 1, 1, 12, 0, 0).in_time_zone('Paris')
-    pirate = Pirate.create!(:catchphrase => 'rrrr', :created_on => time_in_paris)
+    time_in_paris = Time.utc(2014, 1, 1, 12, 0, 0).in_time_zone("Paris")
+    pirate = Pirate.create!(catchphrase: "rrrr", created_on: time_in_paris)
 
-    pirate.created_on = pirate.created_on.in_time_zone('Tokyo').to_s
+    pirate.created_on = pirate.created_on.in_time_zone("Tokyo").to_s
     assert !pirate.created_on_changed?
   end
 
@@ -601,13 +603,13 @@ class DirtyTest < ActiveRecord::TestCase
     with_partial_writes Person do
       jon = nil
       assert_sql(/first_name/i) do
-        jon = Person.create! first_name: 'Jon'
+        jon = Person.create! first_name: "Jon"
       end
 
-      assert ActiveRecord::SQLCounter.log_all.none? { |sql| sql =~ /followers_count/ }
+      assert ActiveRecord::SQLCounter.log_all.none? { |sql| sql.include?("followers_count") }
 
       jon.reload
-      assert_equal 'Jon', jon.first_name
+      assert_equal "Jon", jon.first_name
       assert_equal 0, jon.followers_count
       assert_not_nil jon.id
     end
@@ -633,7 +635,7 @@ class DirtyTest < ActiveRecord::TestCase
     assert_equal("arrrr", pirate.catchphrase_was)
     assert pirate.catchphrase_changed?(from: "arrrr")
     assert_not pirate.catchphrase_changed?(from: "anything else")
-    assert pirate.changed_attributes.include?(:catchphrase)
+    assert_includes pirate.changed_attributes, :catchphrase
 
     pirate.save!
     pirate.reload
@@ -665,6 +667,47 @@ class DirtyTest < ActiveRecord::TestCase
     assert binary.changed?
   end
 
+  test "changes is correct for subclass" do
+    foo = Class.new(Pirate) do
+      def catchphrase
+        super.upcase
+      end
+    end
+
+    pirate = foo.create!(catchphrase: "arrrr")
+
+    new_catchphrase = "arrrr matey!"
+
+    pirate.catchphrase = new_catchphrase
+    assert pirate.catchphrase_changed?
+
+    expected_changes = {
+      "catchphrase" => ["arrrr", new_catchphrase]
+    }
+
+    assert_equal new_catchphrase.upcase, pirate.catchphrase
+    assert_equal expected_changes, pirate.changes
+  end
+
+  test "changes is correct if override attribute reader" do
+    pirate = Pirate.create!(catchphrase: "arrrr")
+    def pirate.catchphrase
+      super.upcase
+    end
+
+    new_catchphrase = "arrrr matey!"
+
+    pirate.catchphrase = new_catchphrase
+    assert pirate.catchphrase_changed?
+
+    expected_changes = {
+      "catchphrase" => ["arrrr", new_catchphrase]
+    }
+
+    assert_equal new_catchphrase.upcase, pirate.catchphrase
+    assert_equal expected_changes, pirate.changes
+  end
+
   test "attribute_changed? doesn't compute in-place changes for unrelated attributes" do
     test_type_class = Class.new(ActiveRecord::Type::Value) do
       define_method(:changed_in_place?) do |*|
@@ -672,7 +715,7 @@ class DirtyTest < ActiveRecord::TestCase
       end
     end
     klass = Class.new(ActiveRecord::Base) do
-      self.table_name = 'people'
+      self.table_name = "people"
       attribute :foo, test_type_class.new
     end
 
@@ -682,7 +725,7 @@ class DirtyTest < ActiveRecord::TestCase
 
   test "attribute_will_change! doesn't try to save non-persistable attributes" do
     klass = Class.new(ActiveRecord::Base) do
-      self.table_name = 'people'
+      self.table_name = "people"
       attribute :non_persisted_attribute, :string
     end
 
@@ -728,6 +771,95 @@ class DirtyTest < ActiveRecord::TestCase
     assert person.changed?
   end
 
+  test "attributes not selected are still missing after save" do
+    person = Person.select(:id).first
+    assert_raises(ActiveModel::MissingAttributeError) { person.first_name }
+    assert person.save # calls forget_attribute_assignments
+    assert_raises(ActiveModel::MissingAttributeError) { person.first_name }
+  end
+
+  test "saved_change_to_attribute? returns whether a change occurred in the last save" do
+    person = Person.create!(first_name: "Sean")
+
+    assert person.saved_change_to_first_name?
+    refute person.saved_change_to_gender?
+    assert person.saved_change_to_first_name?(from: nil, to: "Sean")
+    assert person.saved_change_to_first_name?(from: nil)
+    assert person.saved_change_to_first_name?(to: "Sean")
+    refute person.saved_change_to_first_name?(from: "Jim", to: "Sean")
+    refute person.saved_change_to_first_name?(from: "Jim")
+    refute person.saved_change_to_first_name?(to: "Jim")
+  end
+
+  test "saved_change_to_attribute returns the change that occurred in the last save" do
+    person = Person.create!(first_name: "Sean", gender: "M")
+
+    assert_equal [nil, "Sean"], person.saved_change_to_first_name
+    assert_equal [nil, "M"], person.saved_change_to_gender
+
+    person.update(first_name: "Jim")
+
+    assert_equal ["Sean", "Jim"], person.saved_change_to_first_name
+    assert_nil person.saved_change_to_gender
+  end
+
+  test "attribute_before_last_save returns the original value before saving" do
+    person = Person.create!(first_name: "Sean", gender: "M")
+
+    assert_nil person.first_name_before_last_save
+    assert_nil person.gender_before_last_save
+
+    person.first_name = "Jim"
+
+    assert_nil person.first_name_before_last_save
+    assert_nil person.gender_before_last_save
+
+    person.save
+
+    assert_equal "Sean", person.first_name_before_last_save
+    assert_equal "M", person.gender_before_last_save
+  end
+
+  test "saved_changes? returns whether the last call to save changed anything" do
+    person = Person.create!(first_name: "Sean")
+
+    assert person.saved_changes?
+
+    person.save
+
+    refute person.saved_changes?
+  end
+
+  test "saved_changes returns a hash of all the changes that occurred" do
+    person = Person.create!(first_name: "Sean", gender: "M")
+
+    assert_equal [nil, "Sean"], person.saved_changes[:first_name]
+    assert_equal [nil, "M"], person.saved_changes[:gender]
+    assert_equal %w(id first_name gender created_at updated_at).sort, person.saved_changes.keys.sort
+
+    travel(1.second) do
+      person.update(first_name: "Jim")
+    end
+
+    assert_equal ["Sean", "Jim"], person.saved_changes[:first_name]
+    assert_equal %w(first_name lock_version updated_at).sort, person.saved_changes.keys.sort
+  end
+
+  test "changed? in after callbacks returns false" do
+    klass = Class.new(ActiveRecord::Base) do
+      self.table_name = "people"
+
+      after_save do
+        raise "changed? should be false" if changed?
+        raise "has_changes_to_save? should be false" if has_changes_to_save?
+        raise "saved_changes? should be true" unless saved_changes?
+      end
+    end
+
+    person = klass.create!(first_name: "Sean")
+    refute person.changed?
+  end
+
   private
     def with_partial_writes(klass, on = true)
       old = klass.partial_writes?
diff --git a/activerecord/test/cases/disconnected_test.rb b/activerecord/test/cases/disconnected_test.rb
index c25089a420..533665d0f4 100644
--- a/activerecord/test/cases/disconnected_test.rb
+++ b/activerecord/test/cases/disconnected_test.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require "cases/helper"
 
 class TestRecord < ActiveRecord::Base
diff --git a/activerecord/test/cases/dup_test.rb b/activerecord/test/cases/dup_test.rb
index 638cffe0e6..73da31996e 100644
--- a/activerecord/test/cases/dup_test.rb
+++ b/activerecord/test/cases/dup_test.rb
@@ -1,6 +1,8 @@
+# frozen_string_literal: true
+
 require "cases/helper"
-require 'models/reply'
-require 'models/topic'
+require "models/reply"
+require "models/topic"
 
 module ActiveRecord
   class DupTest < ActiveRecord::TestCase
@@ -14,7 +16,7 @@ module ActiveRecord
       topic = Topic.first
 
       duped = topic.dup
-      assert !duped.readonly?, 'should not be readonly'
+      assert !duped.readonly?, "should not be readonly"
     end
 
     def test_is_readonly
@@ -22,15 +24,15 @@ module ActiveRecord
       topic.readonly!
 
       duped = topic.dup
-      assert duped.readonly?, 'should be readonly'
+      assert duped.readonly?, "should be readonly"
     end
 
     def test_dup_not_persisted
       topic = Topic.first
       duped = topic.dup
 
-      assert !duped.persisted?, 'topic not persisted'
-      assert duped.new_record?, 'topic is new'
+      assert !duped.persisted?, "topic not persisted"
+      assert duped.new_record?, "topic is new"
     end
 
     def test_dup_not_destroyed
@@ -49,9 +51,9 @@ module ActiveRecord
 
     def test_dup_with_modified_attributes
       topic = Topic.first
-      topic.author_name = 'Aaron'
+      topic.author_name = "Aaron"
       duped = topic.dup
-      assert_equal 'Aaron', duped.author_name
+      assert_equal "Aaron", duped.author_name
     end
 
     def test_dup_with_changes
@@ -60,10 +62,10 @@ module ActiveRecord
 
       topic.attributes = dbtopic.attributes.except("id")
 
-      #duped has no timestamp values
+      # duped has no timestamp values
       duped = dbtopic.dup
 
-      #clear topic timestamp values
+      # clear topic timestamp values
       topic.send(:clear_timestamp_attributes)
 
       assert_equal topic.changes, duped.changes
@@ -71,10 +73,10 @@ module ActiveRecord
 
     def test_dup_topics_are_independent
       topic = Topic.first
-      topic.author_name = 'Aaron'
+      topic.author_name = "Aaron"
       duped = topic.dup
 
-      duped.author_name = 'meow'
+      duped.author_name = "meow"
 
       assert_not_equal topic.changes, duped.changes
     end
@@ -83,11 +85,11 @@ module ActiveRecord
       topic = Topic.first
       duped = topic.dup
 
-      duped.author_name = 'meow'
-      topic.author_name = 'Aaron'
+      duped.author_name = "meow"
+      topic.author_name = "Aaron"
 
-      assert_equal 'Aaron', topic.author_name
-      assert_equal 'meow', duped.author_name
+      assert_equal "Aaron", topic.author_name
+      assert_equal "meow", duped.author_name
     end
 
     def test_dup_timestamps_are_cleared
@@ -98,7 +100,7 @@ module ActiveRecord
       # temporary change to the topic object
       topic.updated_at -= 3.days
 
-      #dup should not preserve the timestamps if present
+      # dup should not preserve the timestamps if present
       new_topic = topic.dup
       assert_nil new_topic.updated_at
       assert_nil new_topic.created_at
@@ -127,7 +129,7 @@ module ActiveRecord
         assert duped.invalid?
 
         topic.title = nil
-        duped.title = 'Mathematics'
+        duped.title = "Mathematics"
         assert topic.invalid?
         assert duped.valid?
       end
@@ -135,16 +137,18 @@ module ActiveRecord
 
     def test_dup_with_default_scope
       prev_default_scopes = Topic.default_scopes
-      Topic.default_scopes = [proc { Topic.where(:approved => true) }]
-      topic = Topic.new(:approved => false)
+      Topic.default_scopes = [proc { Topic.where(approved: true) }]
+      topic = Topic.new(approved: false)
       assert !topic.dup.approved?, "should not be overridden by default scopes"
     ensure
       Topic.default_scopes = prev_default_scopes
     end
 
     def test_dup_without_primary_key
+      skip if current_adapter?(:OracleAdapter)
+
       klass = Class.new(ActiveRecord::Base) do
-        self.table_name = 'parrots_pirates'
+        self.table_name = "parrots_pirates"
       end
 
       record = klass.create!
diff --git a/activerecord/test/cases/enum_test.rb b/activerecord/test/cases/enum_test.rb
index babacd1ee9..7cda712112 100644
--- a/activerecord/test/cases/enum_test.rb
+++ b/activerecord/test/cases/enum_test.rb
@@ -1,8 +1,11 @@
-require 'cases/helper'
-require 'models/book'
+# frozen_string_literal: true
+
+require "cases/helper"
+require "models/author"
+require "models/book"
 
 class EnumTest < ActiveRecord::TestCase
-  fixtures :books
+  fixtures :books, :authors, :author_addresses
 
   setup do
     @book = books(:awdr)
@@ -18,6 +21,7 @@ class EnumTest < ActiveRecord::TestCase
     assert @book.author_visibility_visible?
     assert @book.illustrator_visibility_visible?
     assert @book.with_medium_font_size?
+    assert @book.medium_to_read?
   end
 
   test "query state with strings" do
@@ -26,6 +30,7 @@ class EnumTest < ActiveRecord::TestCase
     assert_equal "english", @book.language
     assert_equal "visible", @book.author_visibility
     assert_equal "visible", @book.illustrator_visibility
+    assert_equal "medium", @book.difficulty
   end
 
   test "find via scope" do
@@ -34,6 +39,9 @@ class EnumTest < ActiveRecord::TestCase
     assert_equal @book, Book.in_english.first
     assert_equal @book, Book.author_visibility_visible.first
     assert_equal @book, Book.illustrator_visibility_visible.first
+    assert_equal @book, Book.medium_to_read.first
+    assert_equal books(:ddd), Book.forgotten.first
+    assert_equal books(:rfr), authors(:david).unpublished_books.first
   end
 
   test "find via where with values" do
@@ -54,6 +62,7 @@ class EnumTest < ActiveRecord::TestCase
     assert_not_equal @book, Book.where(status: [:written]).first
     assert_not_equal @book, Book.where.not(status: :published).first
     assert_equal @book, Book.where.not(status: :written).first
+    assert_equal books(:ddd), Book.where(read_status: :forgotten).first
   end
 
   test "find via where with strings" do
@@ -63,6 +72,7 @@ class EnumTest < ActiveRecord::TestCase
     assert_not_equal @book, Book.where(status: ["written"]).first
     assert_not_equal @book, Book.where.not(status: "published").first
     assert_equal @book, Book.where.not(status: "written").first
+    assert_equal books(:ddd), Book.where(read_status: "forgotten").first
   end
 
   test "build from scope" do
@@ -122,8 +132,8 @@ class EnumTest < ActiveRecord::TestCase
     old_language = @book.language
     @book.status = :proposed
     @book.language = :spanish
-    assert_equal [old_status, 'proposed'], @book.changes[:status]
-    assert_equal [old_language, 'spanish'], @book.changes[:language]
+    assert_equal [old_status, "proposed"], @book.changes[:status]
+    assert_equal [old_language, "spanish"], @book.changes[:language]
   end
 
   test "enum attribute was" do
@@ -145,8 +155,8 @@ class EnumTest < ActiveRecord::TestCase
   test "enum attribute changed to" do
     @book.status = :proposed
     @book.language = :french
-    assert @book.attribute_changed?(:status, to: 'proposed')
-    assert @book.attribute_changed?(:language, to: 'french')
+    assert @book.attribute_changed?(:status, to: "proposed")
+    assert @book.attribute_changed?(:language, to: "french")
   end
 
   test "enum attribute changed from" do
@@ -163,8 +173,8 @@ class EnumTest < ActiveRecord::TestCase
     old_language = @book.language
     @book.status = :proposed
     @book.language = :french
-    assert @book.attribute_changed?(:status, from: old_status, to: 'proposed')
-    assert @book.attribute_changed?(:language, from: old_language, to: 'french')
+    assert @book.attribute_changed?(:status, from: old_status, to: "proposed")
+    assert @book.attribute_changed?(:language, from: old_language, to: "french")
   end
 
   test "enum didn't change" do
@@ -216,12 +226,12 @@ class EnumTest < ActiveRecord::TestCase
   end
 
   test "assign empty string value" do
-    @book.status = ''
+    @book.status = ""
     assert_nil @book.status
   end
 
   test "assign long empty string value" do
-    @book.status = '   '
+    @book.status = "   "
     assert_nil @book.status
   end
 
@@ -245,12 +255,14 @@ class EnumTest < ActiveRecord::TestCase
     assert Book.illustrator_visibility_invisible.create.illustrator_visibility_invisible?
   end
 
-  test "_before_type_cast returns the enum label (required for form fields)" do
-    if @book.status_came_from_user?
-      assert_equal "published", @book.status_before_type_cast
-    else
-      assert_equal "published", @book.status
-    end
+  test "_before_type_cast" do
+    assert_equal 2, @book.status_before_type_cast
+    assert_equal "published", @book.status
+
+    @book.status = "published"
+
+    assert_equal "published", @book.status_before_type_cast
+    assert_equal "published", @book.status
   end
 
   test "reserved enum names" do
@@ -296,6 +308,24 @@ class EnumTest < ActiveRecord::TestCase
     end
   end
 
+  test "reserved enum values for relation" do
+    relation_method_samples = [
+      :records,
+      :to_ary,
+      :scope_for_create
+    ]
+
+    relation_method_samples.each do |value|
+      e = assert_raises(ArgumentError, "enum value `#{value}` should not be allowed") do
+        Class.new(ActiveRecord::Base) do
+          self.table_name = "books"
+          enum category: [:other, value]
+        end
+      end
+      assert_match(/You tried to define an enum named .* on the model/, e.message)
+    end
+  end
+
   test "overriding enum method should not raise" do
     assert_nothing_raised do
       Class.new(ActiveRecord::Base) do
@@ -318,7 +348,7 @@ class EnumTest < ActiveRecord::TestCase
 
   test "validate uniqueness" do
     klass = Class.new(ActiveRecord::Base) do
-      def self.name; 'Book'; end
+      def self.name; "Book"; end
       enum status: [:proposed, :written]
       validates_uniqueness_of :status
     end
@@ -332,7 +362,7 @@ class EnumTest < ActiveRecord::TestCase
 
   test "validate inclusion of value in array" do
     klass = Class.new(ActiveRecord::Base) do
-      def self.name; 'Book'; end
+      def self.name; "Book"; end
       enum status: [:proposed, :written]
       validates_inclusion_of :status, in: ["written"]
     end
@@ -356,11 +386,11 @@ class EnumTest < ActiveRecord::TestCase
 
     book1 = klass1.proposed.create!
     book1.status = :written
-    assert_equal ['proposed', 'written'], book1.status_change
+    assert_equal ["proposed", "written"], book1.status_change
 
     book2 = klass2.drafted.create!
     book2.status = :uploaded
-    assert_equal ['drafted', 'uploaded'], book2.status_change
+    assert_equal ["drafted", "uploaded"], book2.status_change
   end
 
   test "enums are inheritable" do
@@ -372,11 +402,11 @@ class EnumTest < ActiveRecord::TestCase
 
     book1 = subklass1.proposed.create!
     book1.status = :written
-    assert_equal ['proposed', 'written'], book1.status_change
+    assert_equal ["proposed", "written"], book1.status_change
 
     book2 = subklass2.drafted.create!
     book2.status = :uploaded
-    assert_equal ['drafted', 'uploaded'], book2.status_change
+    assert_equal ["drafted", "uploaded"], book2.status_change
   end
 
   test "declare multiple enums at a time" do
@@ -393,6 +423,22 @@ class EnumTest < ActiveRecord::TestCase
     assert book2.single?
   end
 
+  test "enum with alias_attribute" do
+    klass = Class.new(ActiveRecord::Base) do
+      self.table_name = "books"
+      alias_attribute :aliased_status, :status
+      enum aliased_status: [:proposed, :written, :published]
+    end
+
+    book = klass.proposed.create!
+    assert book.proposed?
+    assert_equal "proposed", book.aliased_status
+
+    book = klass.find(book.id)
+    assert book.proposed?
+    assert_equal "proposed", book.aliased_status
+  end
+
   test "query state by predicate with prefix" do
     assert @book.author_visibility_visible?
     assert_not @book.author_visibility_invisible?
@@ -406,6 +452,43 @@ class EnumTest < ActiveRecord::TestCase
     assert_not @book.in_french?
   end
 
+  test "query state by predicate with custom suffix" do
+    assert     @book.medium_to_read?
+    assert_not @book.easy_to_read?
+    assert_not @book.hard_to_read?
+  end
+
+  test "enum methods with custom suffix defined" do
+    assert @book.class.respond_to?(:easy_to_read)
+    assert @book.class.respond_to?(:medium_to_read)
+    assert @book.class.respond_to?(:hard_to_read)
+
+    assert @book.respond_to?(:easy_to_read?)
+    assert @book.respond_to?(:medium_to_read?)
+    assert @book.respond_to?(:hard_to_read?)
+
+    assert @book.respond_to?(:easy_to_read!)
+    assert @book.respond_to?(:medium_to_read!)
+    assert @book.respond_to?(:hard_to_read!)
+  end
+
+  test "update enum attributes with custom suffix" do
+    @book.medium_to_read!
+    assert_not @book.easy_to_read?
+    assert     @book.medium_to_read?
+    assert_not @book.hard_to_read?
+
+    @book.easy_to_read!
+    assert     @book.easy_to_read?
+    assert_not @book.medium_to_read?
+    assert_not @book.hard_to_read?
+
+    @book.hard_to_read!
+    assert_not @book.easy_to_read?
+    assert_not @book.medium_to_read?
+    assert     @book.hard_to_read?
+  end
+
   test "uses default status when no status is provided in fixtures" do
     book = books(:tlg)
     assert book.proposed?, "expected fixture to default to proposed status"
@@ -421,4 +504,8 @@ class EnumTest < ActiveRecord::TestCase
     book = Book.new
     assert book.hard?
   end
+
+  test "data type of Enum type" do
+    assert_equal :integer, Book.type_for_attribute("status").type
+  end
 end
diff --git a/activerecord/test/cases/errors_test.rb b/activerecord/test/cases/errors_test.rb
index 0711a372f2..b90e6a66c5 100644
--- a/activerecord/test/cases/errors_test.rb
+++ b/activerecord/test/cases/errors_test.rb
@@ -1,11 +1,13 @@
-require_relative "../cases/helper"
+# frozen_string_literal: true
+
+require "cases/helper"
 
 class ErrorsTest < ActiveRecord::TestCase
   def test_can_be_instantiated_with_no_args
     base = ActiveRecord::ActiveRecordError
     error_klasses = ObjectSpace.each_object(Class).select { |klass| klass < base }
 
-    error_klasses.each do |error_klass|
+    (error_klasses - [ActiveRecord::AmbiguousSourceReflectionForThroughAssociation]).each do |error_klass|
       begin
         error_klass.new.inspect
       rescue ArgumentError
diff --git a/activerecord/test/cases/explain_subscriber_test.rb b/activerecord/test/cases/explain_subscriber_test.rb
index 2dee8a26a5..fb698c47cd 100644
--- a/activerecord/test/cases/explain_subscriber_test.rb
+++ b/activerecord/test/cases/explain_subscriber_test.rb
@@ -1,6 +1,8 @@
-require 'cases/helper'
-require 'active_record/explain_subscriber'
-require 'active_record/explain_registry'
+# frozen_string_literal: true
+
+require "cases/helper"
+require "active_record/explain_subscriber"
+require "active_record/explain_registry"
 
 if ActiveRecord::Base.connection.supports_explain?
   class ExplainSubscriberTest < ActiveRecord::TestCase
@@ -25,31 +27,31 @@ if ActiveRecord::Base.connection.supports_explain?
 
     def test_collects_nothing_if_collect_is_false
       ActiveRecord::ExplainRegistry.collect = false
-      SUBSCRIBER.finish(nil, nil, name: 'SQL', sql: 'select 1 from users', binds: [1, 2])
+      SUBSCRIBER.finish(nil, nil, name: "SQL", sql: "select 1 from users", binds: [1, 2])
       assert queries.empty?
     end
 
     def test_collects_pairs_of_queries_and_binds
-      sql   = 'select 1 from users'
+      sql   = "select 1 from users"
       binds = [1, 2]
-      SUBSCRIBER.finish(nil, nil, name: 'SQL', sql: sql, binds: binds)
+      SUBSCRIBER.finish(nil, nil, name: "SQL", sql: sql, binds: binds)
       assert_equal 1, queries.size
       assert_equal sql, queries[0][0]
       assert_equal binds, queries[0][1]
     end
 
     def test_collects_nothing_if_the_statement_is_not_whitelisted
-      SUBSCRIBER.finish(nil, nil, name: 'SQL', sql: 'SHOW max_identifier_length')
+      SUBSCRIBER.finish(nil, nil, name: "SQL", sql: "SHOW max_identifier_length")
       assert queries.empty?
     end
 
     def test_collects_nothing_if_the_statement_is_only_partially_matched
-      SUBSCRIBER.finish(nil, nil, name: 'SQL', sql: 'select_db yo_mama')
+      SUBSCRIBER.finish(nil, nil, name: "SQL", sql: "select_db yo_mama")
       assert queries.empty?
     end
 
     def test_collects_cte_queries
-      SUBSCRIBER.finish(nil, nil, name: 'SQL', sql: 'with s as (values(3)) select 1 from s')
+      SUBSCRIBER.finish(nil, nil, name: "SQL", sql: "with s as (values(3)) select 1 from s")
       assert_equal 1, queries.size
     end
 
diff --git a/activerecord/test/cases/explain_test.rb b/activerecord/test/cases/explain_test.rb
index 64dfd86ce2..17654027a9 100644
--- a/activerecord/test/cases/explain_test.rb
+++ b/activerecord/test/cases/explain_test.rb
@@ -1,6 +1,8 @@
-require 'cases/helper'
-require 'models/car'
-require 'active_support/core_ext/string/strip'
+# frozen_string_literal: true
+
+require "cases/helper"
+require "models/car"
+require "active_support/core_ext/string/strip"
 
 if ActiveRecord::Base.connection.supports_explain?
   class ExplainTest < ActiveRecord::TestCase
@@ -15,13 +17,13 @@ if ActiveRecord::Base.connection.supports_explain?
     end
 
     def test_relation_explain
-      message = Car.where(:name => 'honda').explain
+      message = Car.where(name: "honda").explain
       assert_match(/^EXPLAIN for:/, message)
     end
 
     def test_collecting_queries_for_explain
       queries = ActiveRecord::Base.collecting_queries_for_explain do
-        Car.where(:name => 'honda').to_a
+        Car.where(name: "honda").to_a
       end
 
       sql, binds = queries[0]
@@ -30,7 +32,7 @@ if ActiveRecord::Base.connection.supports_explain?
         assert_equal 1, binds.length
         assert_equal "honda", binds.last.value
       else
-        assert_match 'honda', sql
+        assert_match "honda", sql
       end
     end
 
@@ -40,17 +42,14 @@ if ActiveRecord::Base.connection.supports_explain?
       queries = sqls.zip(binds)
 
       stub_explain_for_query_plans do
-        expected = sqls.map {|sql| "EXPLAIN for: #{sql}\nquery plan #{sql}"}.join("\n")
+        expected = sqls.map { |sql| "EXPLAIN for: #{sql}\nquery plan #{sql}" }.join("\n")
         assert_equal expected, base.exec_explain(queries)
       end
     end
 
     def test_exec_explain_with_binds
-      object = Struct.new(:name)
-      cols = [object.new('wadus'), object.new('chaflan')]
-
       sqls    = %w(foo bar)
-      binds   = [[[cols[0], 1]], [[cols[1], 2]]]
+      binds   = [[bind_param("wadus", 1)], [bind_param("chaflan", 2)]]
       queries = sqls.zip(binds)
 
       stub_explain_for_query_plans(["query plan foo\n", "query plan bar\n"]) do
@@ -68,20 +67,23 @@ if ActiveRecord::Base.connection.supports_explain?
     def test_unsupported_connection_adapter
       connection.stub(:supports_explain?, false) do
         assert_not_called(base.logger, :warn) do
-          Car.where(:name => 'honda').to_a
+          Car.where(name: "honda").to_a
         end
       end
     end
 
     private
 
-      def stub_explain_for_query_plans(query_plans = ['query plan foo', 'query plan bar'])
+      def stub_explain_for_query_plans(query_plans = ["query plan foo", "query plan bar"])
         explain_called = 0
 
-        connection.stub(:explain, proc{ explain_called += 1; query_plans[explain_called - 1] }) do
+        connection.stub(:explain, proc { explain_called += 1; query_plans[explain_called - 1] }) do
           yield
         end
       end
 
+      def bind_param(name, value)
+        ActiveRecord::Relation::QueryAttribute.new(name, value, ActiveRecord::Type::Value.new)
+      end
   end
 end
diff --git a/activerecord/test/cases/finder_respond_to_test.rb b/activerecord/test/cases/finder_respond_to_test.rb
index 6ab2657c44..4039af66d0 100644
--- a/activerecord/test/cases/finder_respond_to_test.rb
+++ b/activerecord/test/cases/finder_respond_to_test.rb
@@ -1,8 +1,9 @@
+# frozen_string_literal: true
+
 require "cases/helper"
-require 'models/topic'
+require "models/topic"
 
 class FinderRespondToTest < ActiveRecord::TestCase
-
   fixtures :topics
 
   def test_should_preserve_normal_respond_to_behaviour_on_base
@@ -11,7 +12,7 @@ class FinderRespondToTest < ActiveRecord::TestCase
   end
 
   def test_should_preserve_normal_respond_to_behaviour_and_respond_to_newly_added_method
-    class << Topic; self; end.send(:define_method, :method_added_for_finder_respond_to_test) { }
+    class << Topic; self; end.send(:define_method, :method_added_for_finder_respond_to_test) {}
     assert_respond_to Topic, :method_added_for_finder_respond_to_test
   ensure
     class << Topic; self; end.send(:remove_method, :method_added_for_finder_respond_to_test)
@@ -54,7 +55,7 @@ class FinderRespondToTest < ActiveRecord::TestCase
 
   private
 
-  def ensure_topic_method_is_not_cached(method_id)
-    class << Topic; self; end.send(:remove_method, method_id) if Topic.public_methods.include? method_id
-  end
+    def ensure_topic_method_is_not_cached(method_id)
+      class << Topic; self; end.send(:remove_method, method_id) if Topic.public_methods.include? method_id
+    end
 end
diff --git a/activerecord/test/cases/finder_test.rb b/activerecord/test/cases/finder_test.rb
index 6eaaa30cd0..8369a10b5a 100644
--- a/activerecord/test/cases/finder_test.rb
+++ b/activerecord/test/cases/finder_test.rb
@@ -1,35 +1,38 @@
+# frozen_string_literal: true
+
 require "cases/helper"
-require 'models/post'
-require 'models/author'
-require 'models/categorization'
-require 'models/comment'
-require 'models/company'
-require 'models/tagging'
-require 'models/topic'
-require 'models/reply'
-require 'models/entrant'
-require 'models/project'
-require 'models/developer'
-require 'models/computer'
-require 'models/customer'
-require 'models/toy'
-require 'models/matey'
-require 'models/dog'
-require 'models/car'
-require 'models/tyre'
+require "models/post"
+require "models/author"
+require "models/categorization"
+require "models/comment"
+require "models/company"
+require "models/tagging"
+require "models/topic"
+require "models/reply"
+require "models/rating"
+require "models/entrant"
+require "models/project"
+require "models/developer"
+require "models/computer"
+require "models/customer"
+require "models/toy"
+require "models/matey"
+require "models/dog"
+require "models/car"
+require "models/tyre"
 
 class FinderTest < ActiveRecord::TestCase
   fixtures :companies, :topics, :entrants, :developers, :developers_projects, :posts, :comments, :accounts, :authors, :author_addresses, :customers, :categories, :categorizations, :cars
 
   def test_find_by_id_with_hash
-    assert_raises(ActiveRecord::StatementInvalid) do
-      Post.find_by_id(:limit => 1)
+    assert_nothing_raised do
+      Post.find_by_id(limit: 1)
     end
   end
 
   def test_find_by_title_and_id_with_hash
-    assert_raises(ActiveRecord::StatementInvalid) do
-      Post.find_by_title_and_id('foo', :limit => 1)
+    assert_nothing_raised do
+      Post.find_by_title_and_id("foo", limit: 1)
     end
   end
 
@@ -49,76 +52,91 @@ class FinderTest < ActiveRecord::TestCase
   end
 
   def test_find_with_ids_returning_ordered
-    records = Topic.find([4,2,5])
-    assert_equal 'The Fourth Topic of the day', records[0].title
-    assert_equal 'The Second Topic of the day', records[1].title
-    assert_equal 'The Fifth Topic of the day', records[2].title
+    records = Topic.find([4, 2, 5])
+    assert_equal "The Fourth Topic of the day", records[0].title
+    assert_equal "The Second Topic of the day", records[1].title
+    assert_equal "The Fifth Topic of the day", records[2].title
 
-    records = Topic.find(4,2,5)
-    assert_equal 'The Fourth Topic of the day', records[0].title
-    assert_equal 'The Second Topic of the day', records[1].title
-    assert_equal 'The Fifth Topic of the day', records[2].title
+    records = Topic.find(4, 2, 5)
+    assert_equal "The Fourth Topic of the day", records[0].title
+    assert_equal "The Second Topic of the day", records[1].title
+    assert_equal "The Fifth Topic of the day", records[2].title
 
-    records = Topic.find(['4','2','5'])
-    assert_equal 'The Fourth Topic of the day', records[0].title
-    assert_equal 'The Second Topic of the day', records[1].title
-    assert_equal 'The Fifth Topic of the day', records[2].title
+    records = Topic.find(["4", "2", "5"])
+    assert_equal "The Fourth Topic of the day", records[0].title
+    assert_equal "The Second Topic of the day", records[1].title
+    assert_equal "The Fifth Topic of the day", records[2].title
 
-    records = Topic.find('4','2','5')
-    assert_equal 'The Fourth Topic of the day', records[0].title
-    assert_equal 'The Second Topic of the day', records[1].title
-    assert_equal 'The Fifth Topic of the day', records[2].title
+    records = Topic.find("4", "2", "5")
+    assert_equal "The Fourth Topic of the day", records[0].title
+    assert_equal "The Second Topic of the day", records[1].title
+    assert_equal "The Fifth Topic of the day", records[2].title
   end
 
   def test_find_with_ids_and_order_clause
     # The order clause takes precedence over the informed ids
-    records = Topic.order(:author_name).find([5,3,1])
-    assert_equal 'The Third Topic of the day', records[0].title
-    assert_equal 'The First Topic',            records[1].title
-    assert_equal 'The Fifth Topic of the day', records[2].title
+    records = Topic.order(:author_name).find([5, 3, 1])
+    assert_equal "The Third Topic of the day", records[0].title
+    assert_equal "The First Topic",            records[1].title
+    assert_equal "The Fifth Topic of the day", records[2].title
 
-    records = Topic.order(:id).find([5,3,1])
-    assert_equal 'The First Topic',            records[0].title
-    assert_equal 'The Third Topic of the day', records[1].title
-    assert_equal 'The Fifth Topic of the day', records[2].title
+    records = Topic.order(:id).find([5, 3, 1])
+    assert_equal "The First Topic",            records[0].title
+    assert_equal "The Third Topic of the day", records[1].title
+    assert_equal "The Fifth Topic of the day", records[2].title
   end
 
   def test_find_with_ids_with_limit_and_order_clause
     # The order clause takes precedence over the informed ids
-    records = Topic.limit(2).order(:id).find([5,3,1])
+    records = Topic.limit(2).order(:id).find([5, 3, 1])
     assert_equal 2, records.size
-    assert_equal 'The First Topic',            records[0].title
-    assert_equal 'The Third Topic of the day', records[1].title
+    assert_equal "The First Topic",            records[0].title
+    assert_equal "The Third Topic of the day", records[1].title
   end
 
   def test_find_with_ids_and_limit
-    records = Topic.limit(3).find([3,2,5,1,4])
+    records = Topic.limit(3).find([3, 2, 5, 1, 4])
     assert_equal 3, records.size
-    assert_equal 'The Third Topic of the day',  records[0].title
-    assert_equal 'The Second Topic of the day', records[1].title
-    assert_equal 'The Fifth Topic of the day',  records[2].title
+    assert_equal "The Third Topic of the day",  records[0].title
+    assert_equal "The Second Topic of the day", records[1].title
+    assert_equal "The Fifth Topic of the day",  records[2].title
   end
 
   def test_find_with_ids_where_and_limit
     # Please note that Topic 1 is the only not approved so
     # if it were among the first 3 it would raise an ActiveRecord::RecordNotFound
-    records = Topic.where(approved: true).limit(3).find([3,2,5,1,4])
+    records = Topic.where(approved: true).limit(3).find([3, 2, 5, 1, 4])
     assert_equal 3, records.size
-    assert_equal 'The Third Topic of the day',  records[0].title
-    assert_equal 'The Second Topic of the day', records[1].title
-    assert_equal 'The Fifth Topic of the day',  records[2].title
+    assert_equal "The Third Topic of the day",  records[0].title
+    assert_equal "The Second Topic of the day", records[1].title
+    assert_equal "The Fifth Topic of the day",  records[2].title
   end
 
   def test_find_with_ids_and_offset
-    records = Topic.offset(2).find([3,2,5,1,4])
+    records = Topic.offset(2).find([3, 2, 5, 1, 4])
     assert_equal 3, records.size
-    assert_equal 'The Fifth Topic of the day',  records[0].title
-    assert_equal 'The First Topic',             records[1].title
-    assert_equal 'The Fourth Topic of the day', records[2].title
+    assert_equal "The Fifth Topic of the day",  records[0].title
+    assert_equal "The First Topic",             records[1].title
+    assert_equal "The Fourth Topic of the day", records[2].title
+  end
+
+  def test_find_with_ids_with_no_id_passed
+    exception = assert_raises(ActiveRecord::RecordNotFound) { Topic.find }
+    assert_equal exception.model, "Topic"
+    assert_equal exception.primary_key, "id"
+  end
+
+  def test_find_with_ids_with_id_out_of_range
+    exception = assert_raises(ActiveRecord::RecordNotFound) do
+      Topic.find("9999999999999999999999999999999")
+    end
+
+    assert_equal exception.model, "Topic"
+    assert_equal exception.primary_key, "id"
   end
 
-  def test_find_passing_active_record_object_is_deprecated
-    assert_deprecated do
+  def test_find_passing_active_record_object_is_not_permitted
+    assert_raises(ArgumentError) do
       Topic.find(Topic.last)
     end
   end
@@ -127,7 +145,7 @@ class FinderTest < ActiveRecord::TestCase
     gc_disabled = GC.disable
     Post.where("author_id" => nil)  # warm up
     x = Symbol.all_symbols.count
-    Post.where("title" => {"xxxqqqq" => "bar"})
+    Post.where("title" => { "xxxqqqq" => "bar" })
     assert_equal x, Symbol.all_symbols.count
   ensure
     GC.enable if gc_disabled == false
@@ -136,7 +154,7 @@ class FinderTest < ActiveRecord::TestCase
   # find should handle strings that come from URLs
   # (example: Category.find(params[:id]))
   def test_find_with_string
-    assert_equal(Topic.find(1).title,Topic.find("1").title)
+    assert_equal(Topic.find(1).title, Topic.find("1").title)
   end
 
   def test_exists
@@ -144,22 +162,48 @@ class FinderTest < ActiveRecord::TestCase
     assert_equal true, Topic.exists?("1")
     assert_equal true, Topic.exists?(title: "The First Topic")
     assert_equal true, Topic.exists?(heading: "The First Topic")
-    assert_equal true, Topic.exists?(:author_name => "Mary", :approved => true)
+    assert_equal true, Topic.exists?(author_name: "Mary", approved: true)
     assert_equal true, Topic.exists?(["parent_id = ?", 1])
     assert_equal true, Topic.exists?(id: [1, 9999])
 
     assert_equal false, Topic.exists?(45)
     assert_equal false, Topic.exists?(Topic.new.id)
 
-    assert_raise(NoMethodError) { Topic.exists?([1,2]) }
+    assert_raise(NoMethodError) { Topic.exists?([1, 2]) }
+  end
+
+  def test_exists_with_scope
+    davids = Author.where(name: "David")
+    assert_equal true, davids.exists?
+    assert_equal true, davids.exists?(authors(:david).id)
+    assert_equal false, davids.exists?(authors(:mary).id)
+    assert_equal false, davids.exists?("42")
+    assert_equal false, davids.exists?(42)
+    assert_equal false, davids.exists?(davids.new.id)
+
+    fake = Author.where(name: "fake author")
+    assert_equal false, fake.exists?
+    assert_equal false, fake.exists?(authors(:david).id)
+  end
+
+  def test_exists_uses_existing_scope
+    post = authors(:david).posts.first
+    authors = Author.includes(:posts).where(name: "David", posts: { id: post.id })
+    assert_equal true, authors.exists?(authors(:david).id)
+  end
+
+  def test_any_with_scope_on_hash_includes
+    post = authors(:david).posts.first
+    categories = Categorization.includes(author: :posts).where(posts: { id: post.id })
+    assert_equal true, categories.exists?
   end
 
   def test_exists_with_polymorphic_relation
-    post = Post.create!(title: 'Post', body: 'default', taggings: [Tagging.new(comment: 'tagging comment')])
-    relation = Post.tagged_with_comment('tagging comment')
+    post = Post.create!(title: "Post", body: "default", taggings: [Tagging.new(comment: "tagging comment")])
+    relation = Post.tagged_with_comment("tagging comment")
 
-    assert_equal true, relation.exists?(title: ['Post'])
-    assert_equal true, relation.exists?(['title LIKE ?', 'Post%'])
+    assert_equal true, relation.exists?(title: ["Post"])
+    assert_equal true, relation.exists?(["title LIKE ?", "Post%"])
     assert_equal true, relation.exists?
     assert_equal true, relation.exists?(post.id)
     assert_equal true, relation.exists?(post.id.to_s)
@@ -167,15 +211,15 @@ class FinderTest < ActiveRecord::TestCase
     assert_equal false, relation.exists?(false)
   end
 
-  def test_exists_passing_active_record_object_is_deprecated
-    assert_deprecated do
+  def test_exists_passing_active_record_object_is_not_permitted
+    assert_raises(ArgumentError) do
       Topic.exists?(Topic.new)
     end
   end
 
   def test_exists_returns_false_when_parameter_has_invalid_type
     assert_equal false, Topic.exists?("foo")
-    assert_equal false, Topic.exists?(("9"*53).to_i) # number that's bigger than int
+    assert_equal false, Topic.exists?(("9" * 53).to_i) # number that's bigger than int
   end
 
   def test_exists_does_not_select_columns_without_alias
@@ -202,14 +246,32 @@ class FinderTest < ActiveRecord::TestCase
     assert_equal true, Topic.first.replies.exists?
   end
 
-  # ensures +exists?+ runs valid SQL by excluding order value
-  def test_exists_with_order
+  # Ensure +exists?+ runs without an error by excluding distinct value.
+  # See https://github.com/rails/rails/pull/26981.
+  def test_exists_with_order_and_distinct
     assert_equal true, Topic.order(:id).distinct.exists?
   end
 
+  # Ensure +exists?+ runs without an error by excluding order value.
+  def test_exists_with_order
+    assert_equal true, Topic.order(Arel.sql("invalid sql here")).exists?
+  end
+
+  def test_exists_with_joins
+    assert_equal true, Topic.joins(:replies).where(replies_topics: { approved: true }).order("replies_topics.created_at DESC").exists?
+  end
+
+  def test_exists_with_left_joins
+    assert_equal true, Topic.left_joins(:replies).where(replies_topics: { approved: true }).order("replies_topics.created_at DESC").exists?
+  end
+
+  def test_exists_with_eager_load
+    assert_equal true, Topic.eager_load(:replies).where(replies_topics: { approved: true }).order("replies_topics.created_at DESC").exists?
+  end
+
   def test_exists_with_includes_limit_and_empty_result
     assert_equal false, Topic.includes(:replies).limit(0).exists?
-    assert_equal false, Topic.includes(:replies).limit(1).where('0 = 1').exists?
+    assert_equal false, Topic.includes(:replies).limit(1).where("0 = 1").exists?
   end
 
   def test_exists_with_distinct_association_includes_and_limit
@@ -220,8 +282,13 @@ class FinderTest < ActiveRecord::TestCase
 
   def test_exists_with_distinct_association_includes_limit_and_order
     author = Author.first
-    assert_equal false, author.unique_categorized_posts.includes(:special_comments).order('comments.tags_count DESC').limit(0).exists?
-    assert_equal true, author.unique_categorized_posts.includes(:special_comments).order('comments.tags_count DESC').limit(1).exists?
+    assert_equal false, author.unique_categorized_posts.includes(:special_comments).order("comments.tags_count DESC").limit(0).exists?
+    assert_equal true, author.unique_categorized_posts.includes(:special_comments).order("comments.tags_count DESC").limit(1).exists?
+  end
+
+  def test_exists_should_reference_correct_aliases_while_joining_tables_of_has_many_through_association
+    developer = developers(:david)
+    assert_not_predicate developer.ratings.includes(comment: :post).where(posts: { id: 1 }), :exists?
   end
 
   def test_exists_with_empty_table_and_no_args_given
@@ -231,17 +298,14 @@ class FinderTest < ActiveRecord::TestCase
 
   def test_exists_with_aggregate_having_three_mappings
     existing_address = customers(:david).address
-    assert_equal true, Customer.exists?(:address => existing_address)
+    assert_equal true, Customer.exists?(address: existing_address)
   end
 
   def test_exists_with_aggregate_having_three_mappings_with_one_difference
     existing_address = customers(:david).address
-    assert_equal false, Customer.exists?(:address =>
-      Address.new(existing_address.street, existing_address.city, existing_address.country + "1"))
-    assert_equal false, Customer.exists?(:address =>
-      Address.new(existing_address.street, existing_address.city + "1", existing_address.country))
-    assert_equal false, Customer.exists?(:address =>
-      Address.new(existing_address.street + "1", existing_address.city, existing_address.country))
+    assert_equal false, Customer.exists?(address: Address.new(existing_address.street, existing_address.city, existing_address.country + "1"))
+    assert_equal false, Customer.exists?(address: Address.new(existing_address.street, existing_address.city + "1", existing_address.country))
+    assert_equal false, Customer.exists?(address: Address.new(existing_address.street + "1", existing_address.city, existing_address.country))
   end
 
   def test_exists_does_not_instantiate_records
@@ -261,10 +325,10 @@ class FinderTest < ActiveRecord::TestCase
   end
 
   def test_find_by_ids_with_limit_and_offset
-    assert_equal 2, Entrant.limit(2).find([1,3,2]).size
-    entrants = Entrant.limit(3).offset(2).find([1,3,2])
+    assert_equal 2, Entrant.limit(2).find([1, 3, 2]).size
+    entrants = Entrant.limit(3).offset(2).find([1, 3, 2])
     assert_equal 1, entrants.size
-    assert_equal 'Ruby Guru', entrants.first.name
+    assert_equal "Ruby Guru", entrants.first.name
 
     # Also test an edge case: If you have 11 results, and you set a
     #   limit of 3 and offset of 9, then you should find that there
@@ -272,29 +336,29 @@ class FinderTest < ActiveRecord::TestCase
     devs = Developer.all
     last_devs = Developer.limit(3).offset(9).find devs.map(&:id)
     assert_equal 2, last_devs.size
-    assert_equal 'fixture_10', last_devs[0].name
-    assert_equal 'Jamis', last_devs[1].name
+    assert_equal "fixture_10", last_devs[0].name
+    assert_equal "Jamis", last_devs[1].name
   end
 
   def test_find_with_large_number
-    assert_raises(ActiveRecord::RecordNotFound) { Topic.find('9999999999999999999999999999999') }
+    assert_raises(ActiveRecord::RecordNotFound) { Topic.find("9999999999999999999999999999999") }
   end
 
   def test_find_by_with_large_number
-    assert_nil Topic.find_by(id: '9999999999999999999999999999999')
+    assert_nil Topic.find_by(id: "9999999999999999999999999999999")
   end
 
   def test_find_by_id_with_large_number
-    assert_nil Topic.find_by_id('9999999999999999999999999999999')
+    assert_nil Topic.find_by_id("9999999999999999999999999999999")
   end
 
   def test_find_on_relation_with_large_number
-    assert_nil Topic.where('1=1').find_by(id: 9999999999999999999999999999999)
+    assert_nil Topic.where("1=1").find_by(id: 9999999999999999999999999999999)
   end
 
   def test_find_by_bang_on_relation_with_large_number
     assert_raises(ActiveRecord::RecordNotFound) do
-      Topic.where('1=1').find_by!(id: 9999999999999999999999999999999)
+      Topic.where("1=1").find_by!(id: 9999999999999999999999999999999)
     end
   end
 
@@ -311,7 +375,7 @@ class FinderTest < ActiveRecord::TestCase
   end
 
   def test_find_with_group_and_sanitized_having_method
-    developers = Developer.group(:salary).having("sum(salary) > ?", 10000).select('salary').to_a
+    developers = Developer.group(:salary).having("sum(salary) > ?", 10000).select("salary").to_a
     assert_equal 3, developers.size
     assert_equal 3, developers.map(&:salary).uniq.size
     assert developers.all? { |developer| developer.salary > 10000 }
@@ -342,6 +406,11 @@ class FinderTest < ActiveRecord::TestCase
     assert_equal author.post, Post.find_by(author_id: Author.where(id: author))
   end
 
+  def test_find_by_and_where_consistency_with_active_record_instance
+    author = authors(:david)
+    assert_equal Post.where(author_id: author).take, Post.find_by(author_id: author)
+  end
+
   def test_take
     assert_equal topics(:first), Topic.take
   end
@@ -491,12 +560,12 @@ class FinderTest < ActiveRecord::TestCase
     assert_equal topics(:fourth), Topic.offset(1).second_to_last
     assert_equal topics(:fourth), Topic.offset(2).second_to_last
     assert_equal topics(:fourth), Topic.offset(3).second_to_last
-    assert_equal nil, Topic.offset(4).second_to_last
-    assert_equal nil, Topic.offset(5).second_to_last
+    assert_nil Topic.offset(4).second_to_last
+    assert_nil Topic.offset(5).second_to_last
 
-    #test with limit
-    # assert_equal nil, Topic.limit(1).second # TODO: currently failing
-    assert_equal nil, Topic.limit(1).second_to_last
+    # test with limit
+    assert_nil Topic.limit(1).second
+    assert_nil Topic.limit(1).second_to_last
   end
 
   def test_second_to_last_have_primary_key_order_by_default
@@ -519,15 +588,15 @@ class FinderTest < ActiveRecord::TestCase
     # test with offset
     assert_equal topics(:third), Topic.offset(1).third_to_last
     assert_equal topics(:third), Topic.offset(2).third_to_last
-    assert_equal nil, Topic.offset(3).third_to_last
-    assert_equal nil, Topic.offset(4).third_to_last
-    assert_equal nil, Topic.offset(5).third_to_last
+    assert_nil Topic.offset(3).third_to_last
+    assert_nil Topic.offset(4).third_to_last
+    assert_nil Topic.offset(5).third_to_last
 
     # test with limit
-    # assert_equal nil, Topic.limit(1).third # TODO: currently failing
-    assert_equal nil, Topic.limit(1).third_to_last
-    # assert_equal nil, Topic.limit(2).third # TODO: currently failing
-    assert_equal nil, Topic.limit(2).third_to_last
+    assert_nil Topic.limit(1).third
+    assert_nil Topic.limit(1).third_to_last
+    assert_nil Topic.limit(2).third
+    assert_nil Topic.limit(2).third_to_last
   end
 
   def test_third_to_last_have_primary_key_order_by_default
@@ -565,9 +634,9 @@ class FinderTest < ActiveRecord::TestCase
   end
 
   def test_take_and_first_and_last_with_integer_should_use_sql_limit
-    assert_sql(/LIMIT|ROWNUM <=/) { Topic.take(3).entries }
-    assert_sql(/LIMIT|ROWNUM <=/) { Topic.first(2).entries }
-    assert_sql(/LIMIT|ROWNUM <=/) { Topic.last(5).entries }
+    assert_sql(/LIMIT|ROWNUM <=|FETCH FIRST/) { Topic.take(3).entries }
+    assert_sql(/LIMIT|ROWNUM <=|FETCH FIRST/) { Topic.first(2).entries }
+    assert_sql(/LIMIT|ROWNUM <=|FETCH FIRST/) { Topic.last(5).entries }
   end
 
   def test_last_with_integer_and_order_should_keep_the_order
@@ -587,7 +656,7 @@ class FinderTest < ActiveRecord::TestCase
   end
 
   def test_last_on_loaded_relation_should_not_use_sql
-    relation  = Topic.limit(10).load
+    relation = Topic.limit(10).load
     assert_no_queries do
       relation.last
       relation.last(2)
@@ -595,13 +664,13 @@ class FinderTest < ActiveRecord::TestCase
   end
 
   def test_last_with_irreversible_order
-    assert_deprecated do
-      Topic.order("coalesce(author_name, title)").last
+    assert_raises(ActiveRecord::IrreversibleOrderError) do
+      Topic.order(Arel.sql("coalesce(author_name, title)")).last
     end
   end
 
   def test_last_on_relation_with_limit_and_offset
-    post = posts('sti_comments')
+    post = posts("sti_comments")
 
     comments = post.comments.order(id: :asc)
     assert_equal comments.limit(2).to_a.last, comments.limit(2).last
@@ -630,8 +699,8 @@ class FinderTest < ActiveRecord::TestCase
 
   def test_find_only_some_columns
     topic = Topic.select("author_name").find(1)
-    assert_raise(ActiveModel::MissingAttributeError) {topic.title}
-    assert_raise(ActiveModel::MissingAttributeError) {topic.title?}
+    assert_raise(ActiveModel::MissingAttributeError) { topic.title }
+    assert_raise(ActiveModel::MissingAttributeError) { topic.title? }
     assert_nil topic.read_attribute("title")
     assert_equal "David", topic.author_name
     assert !topic.attribute_present?("title")
@@ -651,8 +720,8 @@ class FinderTest < ActiveRecord::TestCase
   end
 
   def test_find_on_hash_conditions_with_qualified_attribute_dot_notation_string
-    assert Topic.where('topics.approved' => false).find(1)
-    assert_raise(ActiveRecord::RecordNotFound) { Topic.where('topics.approved' => true).find(1) }
+    assert Topic.where("topics.approved" => false).find(1)
+    assert_raise(ActiveRecord::RecordNotFound) { Topic.where("topics.approved" => true).find(1) }
   end
 
   def test_find_on_hash_conditions_with_qualified_attribute_dot_notation_symbol
@@ -666,28 +735,28 @@ class FinderTest < ActiveRecord::TestCase
   end
 
   def test_find_on_combined_explicit_and_hashed_table_names
-    assert Topic.where('topics.approved' => false, topics: { author_name: "David" }).find(1)
-    assert_raise(ActiveRecord::RecordNotFound) { Topic.where('topics.approved' => true, topics: { author_name: "David" }).find(1) }
-    assert_raise(ActiveRecord::RecordNotFound) { Topic.where('topics.approved' => false, topics: { author_name: "Melanie" }).find(1) }
+    assert Topic.where("topics.approved" => false, topics: { author_name: "David" }).find(1)
+    assert_raise(ActiveRecord::RecordNotFound) { Topic.where("topics.approved" => true, topics: { author_name: "David" }).find(1) }
+    assert_raise(ActiveRecord::RecordNotFound) { Topic.where("topics.approved" => false, topics: { author_name: "Melanie" }).find(1) }
   end
 
   def test_find_with_hash_conditions_on_joined_table
-    firms = Firm.joins(:account).where(:accounts => { :credit_limit => 50 })
+    firms = Firm.joins(:account).where(accounts: { credit_limit: 50 })
     assert_equal 1, firms.size
     assert_equal companies(:first_firm), firms.first
   end
 
   def test_find_with_hash_conditions_on_joined_table_and_with_range
-    firms = DependentFirm.joins(:account).where(name: 'RailsCore', accounts: { credit_limit: 55..60 })
+    firms = DependentFirm.joins(:account).where(name: "RailsCore", accounts: { credit_limit: 55..60 })
     assert_equal 1, firms.size
     assert_equal companies(:rails_core), firms.first
   end
 
   def test_find_on_hash_conditions_with_explicit_table_name_and_aggregate
     david = customers(:david)
-    assert Customer.where('customers.name' => david.name, :address => david.address).find(david.id)
+    assert Customer.where("customers.name" => david.name, :address => david.address).find(david.id)
     assert_raise(ActiveRecord::RecordNotFound) {
-      Customer.where('customers.name' => david.name + "1", :address => david.address).find(david.id)
+      Customer.where("customers.name" => david.name + "1", :address => david.address).find(david.id)
     }
   end
 
@@ -696,34 +765,33 @@ class FinderTest < ActiveRecord::TestCase
   end
 
   def test_find_on_hash_conditions_with_range
-    assert_equal [1,2], Topic.where(id: 1..2).to_a.map(&:id).sort
+    assert_equal [1, 2], Topic.where(id: 1..2).to_a.map(&:id).sort
     assert_raise(ActiveRecord::RecordNotFound) { Topic.where(id: 2..3).find(1) }
   end
 
   def test_find_on_hash_conditions_with_end_exclusive_range
-    assert_equal [1,2,3], Topic.where(id: 1..3).to_a.map(&:id).sort
-    assert_equal [1,2], Topic.where(id: 1...3).to_a.map(&:id).sort
+    assert_equal [1, 2, 3], Topic.where(id: 1..3).to_a.map(&:id).sort
+    assert_equal [1, 2], Topic.where(id: 1...3).to_a.map(&:id).sort
     assert_raise(ActiveRecord::RecordNotFound) { Topic.where(id: 2...3).find(3) }
   end
 
   def test_find_on_hash_conditions_with_multiple_ranges
-    assert_equal [1,2,3], Comment.where(id: 1..3, post_id: 1..2).to_a.map(&:id).sort
+    assert_equal [1, 2, 3], Comment.where(id: 1..3, post_id: 1..2).to_a.map(&:id).sort
     assert_equal [1], Comment.where(id: 1..1, post_id: 1..10).to_a.map(&:id).sort
   end
 
   def test_find_on_hash_conditions_with_array_of_integers_and_ranges
-    assert_equal [1,2,3,5,6,7,8,9], Comment.where(id: [1..2, 3, 5, 6..8, 9]).to_a.map(&:id).sort
+    assert_equal [1, 2, 3, 5, 6, 7, 8, 9], Comment.where(id: [1..2, 3, 5, 6..8, 9]).to_a.map(&:id).sort
   end
 
   def test_find_on_hash_conditions_with_array_of_ranges
-    assert_equal [1,2,6,7,8], Comment.where(id: [1..2, 6..8]).to_a.map(&:id).sort
+    assert_equal [1, 2, 6, 7, 8], Comment.where(id: [1..2, 6..8]).to_a.map(&:id).sort
   end
 
   def test_find_on_multiple_hash_conditions
     assert Topic.where(author_name: "David", title: "The First Topic", replies_count: 1, approved: false).find(1)
     assert_raise(ActiveRecord::RecordNotFound) { Topic.where(author_name: "David", title: "The First Topic", replies_count: 1, approved: true).find(1) }
     assert_raise(ActiveRecord::RecordNotFound) { Topic.where(author_name: "David", title: "HHC", replies_count: 1, approved: false).find(1) }
-    assert_raise(ActiveRecord::RecordNotFound) { Topic.where(author_name: "David", title: "The First Topic", replies_count: 1, approved: true).find(1) }
   end
 
   def test_condition_interpolation
@@ -758,9 +826,9 @@ class FinderTest < ActiveRecord::TestCase
   end
 
   def test_hash_condition_find_with_array
-    p1, p2 = Post.limit(2).order('id asc').to_a
-    assert_equal [p1, p2], Post.where(id: [p1, p2]).order('id asc').to_a
-    assert_equal [p1, p2], Post.where(id: [p1, p2.id]).order('id asc').to_a
+    p1, p2 = Post.limit(2).order("id asc").to_a
+    assert_equal [p1, p2], Post.where(id: [p1, p2]).order("id asc").to_a
+    assert_equal [p1, p2], Post.where(id: [p1, p2.id]).order("id asc").to_a
   end
 
   def test_hash_condition_find_with_nil
@@ -772,56 +840,56 @@ class FinderTest < ActiveRecord::TestCase
   def test_hash_condition_find_with_aggregate_having_one_mapping
     balance = customers(:david).balance
     assert_kind_of Money, balance
-    found_customer = Customer.where(:balance => balance).first
+    found_customer = Customer.where(balance: balance).first
     assert_equal customers(:david), found_customer
   end
 
   def test_hash_condition_find_with_aggregate_attribute_having_same_name_as_field_and_key_value_being_aggregate
     gps_location = customers(:david).gps_location
     assert_kind_of GpsLocation, gps_location
-    found_customer = Customer.where(:gps_location => gps_location).first
+    found_customer = Customer.where(gps_location: gps_location).first
     assert_equal customers(:david), found_customer
   end
 
   def test_hash_condition_find_with_aggregate_having_one_mapping_and_key_value_being_attribute_value
     balance = customers(:david).balance
     assert_kind_of Money, balance
-    found_customer = Customer.where(:balance => balance.amount).first
+    found_customer = Customer.where(balance: balance.amount).first
     assert_equal customers(:david), found_customer
   end
 
   def test_hash_condition_find_with_aggregate_attribute_having_same_name_as_field_and_key_value_being_attribute_value
     gps_location = customers(:david).gps_location
     assert_kind_of GpsLocation, gps_location
-    found_customer = Customer.where(:gps_location => gps_location.gps_location).first
+    found_customer = Customer.where(gps_location: gps_location.gps_location).first
     assert_equal customers(:david), found_customer
   end
 
   def test_hash_condition_find_with_aggregate_having_three_mappings
     address = customers(:david).address
     assert_kind_of Address, address
-    found_customer = Customer.where(:address => address).first
+    found_customer = Customer.where(address: address).first
     assert_equal customers(:david), found_customer
   end
 
   def test_hash_condition_find_with_one_condition_being_aggregate_and_another_not
     address = customers(:david).address
     assert_kind_of Address, address
-    found_customer = Customer.where(:address => address, :name => customers(:david).name).first
+    found_customer = Customer.where(address: address, name: customers(:david).name).first
     assert_equal customers(:david), found_customer
   end
 
   def test_condition_utc_time_interpolation_with_default_timezone_local
-    with_env_tz 'America/New_York' do
+    with_env_tz "America/New_York" do
       with_timezone_config default: :local do
         topic = Topic.first
-        assert_equal topic, Topic.where(['written_on = ?', topic.written_on.getutc]).first
+        assert_equal topic, Topic.where(["written_on = ?", topic.written_on.getutc]).first
       end
     end
   end
 
   def test_hash_condition_utc_time_interpolation_with_default_timezone_local
-    with_env_tz 'America/New_York' do
+    with_env_tz "America/New_York" do
       with_timezone_config default: :local do
         topic = Topic.first
         assert_equal topic, Topic.where(written_on: topic.written_on.getutc).first
@@ -830,16 +898,16 @@ class FinderTest < ActiveRecord::TestCase
   end
 
   def test_condition_local_time_interpolation_with_default_timezone_utc
-    with_env_tz 'America/New_York' do
+    with_env_tz "America/New_York" do
       with_timezone_config default: :utc do
         topic = Topic.first
-        assert_equal topic, Topic.where(['written_on = ?', topic.written_on.getlocal]).first
+        assert_equal topic, Topic.where(["written_on = ?", topic.written_on.getlocal]).first
       end
     end
   end
 
   def test_hash_condition_local_time_interpolation_with_default_timezone_utc
-    with_env_tz 'America/New_York' do
+    with_env_tz "America/New_York" do
       with_timezone_config default: :utc do
         topic = Topic.first
         assert_equal topic, Topic.where(written_on: topic.written_on.getlocal).first
@@ -856,18 +924,18 @@ class FinderTest < ActiveRecord::TestCase
       Company.where(["id=? AND name = ?", 2]).first
     }
     assert_raise(ActiveRecord::PreparedStatementInvalid) {
-     Company.where(["id=?", 2, 3, 4]).first
+      Company.where(["id=?", 2, 3, 4]).first
     }
   end
 
   def test_bind_variables_with_quotes
-    Company.create("name" => "37signals' go'es agains")
-    assert Company.where(["name = ?", "37signals' go'es agains"]).first
+    Company.create("name" => "37signals' go'es against")
+    assert Company.where(["name = ?", "37signals' go'es against"]).first
   end
 
   def test_named_bind_variables_with_quotes
-    Company.create("name" => "37signals' go'es agains")
-    assert Company.where(["name = :name", {name: "37signals' go'es agains"}]).first
+    Company.create("name" => "37signals' go'es against")
+    assert Company.where(["name = :name", { name: "37signals' go'es against" }]).first
   end
 
   def test_named_bind_variables
@@ -877,11 +945,6 @@ class FinderTest < ActiveRecord::TestCase
     assert_kind_of Time, Topic.where(["id = :id", { id: 1 }]).first.written_on
   end
 
-  def test_string_sanitation
-    assert_not_equal "'something ' 1=1'", ActiveRecord::Base.sanitize("something ' 1=1")
-    assert_equal "'something; select table'", ActiveRecord::Base.sanitize("something; select table")
-  end
-
   def test_count_by_sql
     assert_equal(0, Entrant.count_by_sql("SELECT COUNT(*) FROM entrants WHERE id > 3"))
     assert_equal(1, Entrant.count_by_sql(["SELECT COUNT(*) FROM entrants WHERE id > ?", 2]))
@@ -901,7 +964,7 @@ class FinderTest < ActiveRecord::TestCase
   end
 
   def test_find_by_on_attribute_that_is_a_reserved_word
-    dog_alias = 'Dog'
+    dog_alias = "Dog"
     dog = Dog.create(alias: dog_alias)
 
     assert_equal dog, Dog.find_by_alias(dog_alias)
@@ -918,7 +981,7 @@ class FinderTest < ActiveRecord::TestCase
   end
 
   def test_find_by_one_attribute_with_conditions
-    assert_equal accounts(:rails_core_account), Account.where('firm_id = ?', 6).find_by_credit_limit(50)
+    assert_equal accounts(:rails_core_account), Account.where("firm_id = ?", 6).find_by_credit_limit(50)
   end
 
   def test_find_by_one_attribute_that_is_an_aggregate
@@ -958,12 +1021,12 @@ class FinderTest < ActiveRecord::TestCase
   def test_dynamic_finder_on_one_attribute_with_conditions_returns_same_results_after_caching
     # ensure this test can run independently of order
     class << Account; self; end.send(:remove_method, :find_by_credit_limit) if Account.public_methods.include?(:find_by_credit_limit)
-    a = Account.where('firm_id = ?', 6).find_by_credit_limit(50)
-    assert_equal a, Account.where('firm_id = ?', 6).find_by_credit_limit(50) # find_by_credit_limit has been cached
+    a = Account.where("firm_id = ?", 6).find_by_credit_limit(50)
+    assert_equal a, Account.where("firm_id = ?", 6).find_by_credit_limit(50) # find_by_credit_limit has been cached
   end
 
   def test_find_by_one_attribute_with_several_options
-    assert_equal accounts(:unknown), Account.order('id DESC').where('id != ?', 3).find_by_credit_limit(50)
+    assert_equal accounts(:unknown), Account.order("id DESC").where("id != ?", 3).find_by_credit_limit(50)
   end
 
   def test_find_by_one_missing_attribute
@@ -987,12 +1050,11 @@ class FinderTest < ActiveRecord::TestCase
   end
 
   def test_find_last_with_offset
-    devs = Developer.order('id')
+    devs = Developer.order("id")
 
     assert_equal devs[2], Developer.offset(2).first
     assert_equal devs[-3], Developer.offset(2).last
-    assert_equal devs[-3], Developer.offset(2).last
-    assert_equal devs[-3], Developer.offset(2).order('id DESC').first
+    assert_equal devs[-3], Developer.offset(2).order("id DESC").first
   end
 
   def test_find_by_nil_attribute
@@ -1010,20 +1072,10 @@ class FinderTest < ActiveRecord::TestCase
     assert_raise(ActiveRecord::StatementInvalid) { Topic.find_by_sql "select 1 from badtable" }
   end
 
-  def test_find_all_with_join
-    developers_on_project_one = Developer.
-      joins('LEFT JOIN developers_projects ON developers.id = developers_projects.developer_id').
-      where('project_id=1').to_a
-    assert_equal 3, developers_on_project_one.length
-    developer_names = developers_on_project_one.map(&:name)
-    assert developer_names.include?('David')
-    assert developer_names.include?('Jamis')
-  end
-
   def test_joins_dont_clobber_id
     first = Firm.
-      joins('INNER JOIN companies clients ON clients.firm_id = companies.id').
-      where('companies.id = 1').first
+      joins("INNER JOIN companies clients ON clients.firm_id = companies.id").
+      where("companies.id = 1").first
     assert_equal 1, first.id
   end
 
@@ -1037,12 +1089,12 @@ class FinderTest < ActiveRecord::TestCase
 
   def test_find_by_id_with_conditions_with_or
     assert_nothing_raised do
-      Post.where("posts.id <= 3 OR posts.#{QUOTED_TYPE} = 'Post'").find([1,2,3])
+      Post.where("posts.id <= 3 OR posts.#{QUOTED_TYPE} = 'Post'").find([1, 2, 3])
     end
   end
 
   def test_find_ignores_previously_inserted_record
-    Post.create!(:title => 'test', :body => 'it out')
+    Post.create!(title: "test", body: "it out")
     assert_equal [], Post.where(id: nil)
   end
 
@@ -1051,13 +1103,13 @@ class FinderTest < ActiveRecord::TestCase
   end
 
   def test_find_by_empty_in_condition
-    assert_equal [], Post.where('id in (?)', [])
+    assert_equal [], Post.where("id in (?)", [])
   end
 
   def test_find_by_records
-    p1, p2 = Post.limit(2).order('id asc').to_a
-    assert_equal [p1, p2], Post.where(['id in (?)', [p1, p2]]).order('id asc')
-    assert_equal [p1, p2], Post.where(['id in (?)', [p1, p2.id]]).order('id asc')
+    p1, p2 = Post.limit(2).order("id asc").to_a
+    assert_equal [p1, p2], Post.where(["id in (?)", [p1, p2]]).order("id asc")
+    assert_equal [p1, p2], Post.where(["id in (?)", [p1, p2.id]]).order("id asc")
   end
 
   def test_select_value
@@ -1069,8 +1121,8 @@ class FinderTest < ActiveRecord::TestCase
   end
 
   def test_select_values
-    assert_equal ["1","2","3","4","5","6","7","8","9", "10", "11"], Company.connection.select_values("SELECT id FROM companies ORDER BY id").map!(&:to_s)
-    assert_equal ["37signals","Summit","Microsoft", "Flamboyant Software", "Ex Nihilo", "RailsCore", "Leetsoft", "Jadedpixel", "Odegy", "Ex Nihilo Part Deux", "Apex"], Company.connection.select_values("SELECT name FROM companies ORDER BY id")
+    assert_equal ["1", "2", "3", "4", "5", "6", "7", "8", "9", "10", "11"], Company.connection.select_values("SELECT id FROM companies ORDER BY id").map!(&:to_s)
+    assert_equal ["37signals", "Summit", "Microsoft", "Flamboyant Software", "Ex Nihilo", "RailsCore", "Leetsoft", "Jadedpixel", "Odegy", "Ex Nihilo Part Deux", "Apex"], Company.connection.select_values("SELECT name FROM companies ORDER BY id")
   end
 
   def test_select_rows
@@ -1078,36 +1130,36 @@ class FinderTest < ActiveRecord::TestCase
       [["1", "1", nil, "37signals"],
        ["2", "1", "2", "Summit"],
        ["3", "1", "1", "Microsoft"]],
-      Company.connection.select_rows("SELECT id, firm_id, client_of, name FROM companies WHERE id IN (1,2,3) ORDER BY id").map! {|i| i.map! {|j| j.to_s unless j.nil?}})
+      Company.connection.select_rows("SELECT id, firm_id, client_of, name FROM companies WHERE id IN (1,2,3) ORDER BY id").map! { |i| i.map! { |j| j.to_s unless j.nil? } })
     assert_equal [["1", "37signals"], ["2", "Summit"], ["3", "Microsoft"]],
-      Company.connection.select_rows("SELECT id, name FROM companies WHERE id IN (1,2,3) ORDER BY id").map! {|i| i.map! {|j| j.to_s unless j.nil?}}
+      Company.connection.select_rows("SELECT id, name FROM companies WHERE id IN (1,2,3) ORDER BY id").map! { |i| i.map! { |j| j.to_s unless j.nil? } }
   end
 
   def test_find_with_order_on_included_associations_with_construct_finder_sql_for_association_limiting_and_is_distinct
     assert_equal 2, Post.includes(authors: :author_address).
       where.not(author_addresses: { id: nil }).
-      order('author_addresses.id DESC').limit(2).to_a.size
+      order("author_addresses.id DESC").limit(2).to_a.size
 
     assert_equal 3, Post.includes(author: :author_address, authors: :author_address).
       where.not(author_addresses_authors: { id: nil }).
-      order('author_addresses_authors.id DESC').limit(3).to_a.size
+      order("author_addresses_authors.id DESC").limit(3).to_a.size
   end
 
   def test_find_with_nil_inside_set_passed_for_one_attribute
     client_of = Company.
       where(client_of: [2, 1, nil],
-            name: ['37signals', 'Summit', 'Microsoft']).
-      order('client_of DESC').
+            name: ["37signals", "Summit", "Microsoft"]).
+      order("client_of DESC").
       map(&:client_of)
 
-    assert client_of.include?(nil)
+    assert_includes client_of, nil
     assert_equal [2, 1].sort, client_of.compact.sort
   end
 
   def test_find_with_nil_inside_set_passed_for_attribute
     client_of = Company.
       where(client_of: [nil]).
-      order('client_of DESC').
+      order("client_of DESC").
       map(&:client_of)
 
     assert_equal [], client_of.compact
@@ -1115,20 +1167,30 @@ class FinderTest < ActiveRecord::TestCase
 
   def test_with_limiting_with_custom_select
     posts = Post.references(:authors).merge(
-      :includes => :author, :select => 'posts.*, authors.id as "author_id"',
-      :limit => 3, :order => 'posts.id'
+      includes: :author, select: 'posts.*, authors.id as "author_id"',
+      limit: 3, order: "posts.id"
     ).to_a
     assert_equal 3, posts.size
     assert_equal [0, 1, 1], posts.map(&:author_id).sort
   end
 
+  def test_find_one_message_on_primary_key
+    e = assert_raises(ActiveRecord::RecordNotFound) do
+      Car.find(0)
+    end
+    assert_equal 0, e.id
+    assert_equal "id", e.primary_key
+    assert_equal "Car", e.model
+    assert_equal "Couldn't find Car with 'id'=0", e.message
+  end
+
   def test_find_one_message_with_custom_primary_key
     table_with_custom_primary_key do |model|
       model.primary_key = :name
       e = assert_raises(ActiveRecord::RecordNotFound) do
-        model.find 'Hello World!'
+        model.find "Hello World!"
       end
-      assert_equal %Q{Couldn't find MercedesCar with 'name'=Hello World!}, e.message
+      assert_equal "Couldn't find MercedesCar with 'name'=Hello World!", e.message
     end
   end
 
@@ -1136,9 +1198,9 @@ class FinderTest < ActiveRecord::TestCase
     table_with_custom_primary_key do |model|
       model.primary_key = :name
       e = assert_raises(ActiveRecord::RecordNotFound) do
-        model.find 'Hello', 'World!'
+        model.find "Hello", "World!"
       end
-      assert_equal %Q{Couldn't find all MercedesCars with 'name': (Hello, World!) (found 0 results, but was looking for 2)}, e.message
+      assert_equal "Couldn't find all MercedesCars with 'name': (Hello, World!) (found 0 results, but was looking for 2).", e.message
     end
   end
 
@@ -1161,16 +1223,20 @@ class FinderTest < ActiveRecord::TestCase
   end
 
   test "find_by with multi-arg conditions returns the first matching record" do
-    assert_equal posts(:eager_other), Post.find_by('id = ?', posts(:eager_other).id)
+    assert_equal posts(:eager_other), Post.find_by("id = ?", posts(:eager_other).id)
+  end
+
+  test "find_by with range conditions returns the first matching record" do
+    assert_equal posts(:eager_other), Post.find_by(id: posts(:eager_other).id...posts(:misc_by_bob).id)
   end
 
   test "find_by returns nil if the record is missing" do
-    assert_equal nil, Post.find_by("1 = 0")
+    assert_nil Post.find_by("1 = 0")
   end
 
   test "find_by with associations" do
     assert_equal authors(:david), Post.find_by(author: authors(:david)).author
-    assert_equal authors(:mary) , Post.find_by(author: authors(:mary) ).author
+    assert_equal authors(:mary), Post.find_by(author: authors(:mary)).author
   end
 
   test "find_by doesn't have implicit ordering" do
@@ -1186,7 +1252,7 @@ class FinderTest < ActiveRecord::TestCase
   end
 
   test "find_by! with multi-arg conditions returns the first matching record" do
-    assert_equal posts(:eager_other), Post.find_by!('id = ?', posts(:eager_other).id)
+    assert_equal posts(:eager_other), Post.find_by!("id = ?", posts(:eager_other).id)
   end
 
   test "find_by! doesn't have implicit ordering" do
@@ -1219,11 +1285,39 @@ class FinderTest < ActiveRecord::TestCase
     assert_equal tyre2, zyke.tyres.custom_find_by(id: tyre2.id)
   end
 
-  protected
+  test "#skip_query_cache! for #exists?" do
+    Topic.cache do
+      assert_queries(1) do
+        Topic.exists?
+        Topic.exists?
+      end
+
+      assert_queries(2) do
+        Topic.all.skip_query_cache!.exists?
+        Topic.all.skip_query_cache!.exists?
+      end
+    end
+  end
+
+  test "#skip_query_cache! for #exists? with a limited eager load" do
+    Topic.cache do
+      assert_queries(2) do
+        Topic.eager_load(:replies).limit(1).exists?
+        Topic.eager_load(:replies).limit(1).exists?
+      end
+
+      assert_queries(4) do
+        Topic.eager_load(:replies).limit(1).skip_query_cache!.exists?
+        Topic.eager_load(:replies).limit(1).skip_query_cache!.exists?
+      end
+    end
+  end
+
+  private
     def table_with_custom_primary_key
       yield(Class.new(Toy) do
         def self.name
-          'MercedesCar'
+          "MercedesCar"
         end
       end)
     end
@@ -1232,5 +1326,4 @@ class FinderTest < ActiveRecord::TestCase
       err = assert_raises(exception_class) { block.call }
       assert_match message, err.message
     end
-
 end
diff --git a/activerecord/test/cases/fixture_set/file_test.rb b/activerecord/test/cases/fixture_set/file_test.rb
index e64b90507e..ff99988cb5 100644
--- a/activerecord/test/cases/fixture_set/file_test.rb
+++ b/activerecord/test/cases/fixture_set/file_test.rb
@@ -1,5 +1,7 @@
-require 'cases/helper'
-require 'tempfile'
+# frozen_string_literal: true
+
+require "cases/helper"
+require "tempfile"
 
 module ActiveRecord
   class FixtureSet
@@ -15,7 +17,7 @@ module ActiveRecord
           called = true
           assert_equal 6, fh.to_a.length
         end
-        assert called, 'block called'
+        assert called, "block called"
       end
 
       def test_names
@@ -31,8 +33,8 @@ module ActiveRecord
 
       def test_values
         File.open(::File.join(FIXTURES_ROOT, "accounts.yml")) do |fh|
-          assert_equal [1,2,3,4,5,6].sort, fh.to_a.map(&:last).map { |x|
-            x['id']
+          assert_equal [1, 2, 3, 4, 5, 6].sort, fh.to_a.map(&:last).map { |x|
+            x["id"]
           }.sort
         end
       end
@@ -45,7 +47,7 @@ module ActiveRecord
       end
 
       def test_empty_file
-        tmp_yaml ['empty', 'yml'], '' do |t|
+        tmp_yaml ["empty", "yml"], "" do |t|
           assert_equal [], File.open(t.path) { |fh| fh.to_a }
         end
       end
@@ -53,7 +55,7 @@ module ActiveRecord
       # A valid YAML file is not necessarily a value Fixture file. Make sure
       # an exception is raised if the format is not valid Fixture format.
       def test_wrong_fixture_format_string
-        tmp_yaml ['empty', 'yml'], 'qwerty' do |t|
+        tmp_yaml ["empty", "yml"], "qwerty" do |t|
           assert_raises(ActiveRecord::Fixture::FormatError) do
             File.open(t.path) { |fh| fh.to_a }
           end
@@ -61,7 +63,7 @@ module ActiveRecord
       end
 
       def test_wrong_fixture_format_nested
-        tmp_yaml ['empty', 'yml'], 'one: two' do |t|
+        tmp_yaml ["empty", "yml"], "one: two" do |t|
           assert_raises(ActiveRecord::Fixture::FormatError) do
             File.open(t.path) { |fh| fh.to_a }
           end
@@ -75,9 +77,9 @@ module ActiveRecord
           end
         end
         yaml = "one:\n  name: <%= fixture_helper %>\n"
-        tmp_yaml ['curious', 'yml'], yaml do |t|
+        tmp_yaml ["curious", "yml"], yaml do |t|
           golden =
-              [["one", {"name" => "Fixture helper"}]]
+              [["one", { "name" => "Fixture helper" }]]
           assert_equal golden, File.open(t.path) { |fh| fh.to_a }
         end
         ActiveRecord::FixtureSet.context_class.class_eval do
@@ -95,15 +97,15 @@ one:
   File: <%= File.name %>
 END
 
-        golden = [['one', {
-          'ActiveRecord' => 'constant',
-          'ActiveRecord_FixtureSet' => 'constant',
-          'FixtureSet' => nil,
-          'ActiveRecord_FixtureSet_File' => 'constant',
-          'File' => 'File'
+        golden = [["one", {
+          "ActiveRecord" => "constant",
+          "ActiveRecord_FixtureSet" => "constant",
+          "FixtureSet" => nil,
+          "ActiveRecord_FixtureSet_File" => "constant",
+          "File" => "File"
         }]]
 
-        tmp_yaml ['curious', 'yml'], yaml do |t|
+        tmp_yaml ["curious", "yml"], yaml do |t|
           assert_equal golden, File.open(t.path) { |fh| fh.to_a }
         end
       end
@@ -113,8 +115,8 @@ END
       def test_independent_render_contexts
         yaml1 = "<% def leaked_method; 'leak'; end %>\n"
         yaml2 = "one:\n  name: <%= leaked_method %>\n"
-        tmp_yaml ['leaky', 'yml'], yaml1 do |t1|
-          tmp_yaml ['curious', 'yml'], yaml2 do |t2|
+        tmp_yaml ["leaky", "yml"], yaml1 do |t1|
+          tmp_yaml ["curious", "yml"], yaml2 do |t2|
             File.open(t1.path) { |fh| fh.to_a }
             assert_raises(NameError) do
               File.open(t2.path) { |fh| fh.to_a }
@@ -124,33 +126,33 @@ END
       end
 
       def test_removes_fixture_config_row
-        File.open(::File.join(FIXTURES_ROOT, 'other_posts.yml')) do |fh|
-          assert_equal(['second_welcome'], fh.each.map { |name, _| name })
+        File.open(::File.join(FIXTURES_ROOT, "other_posts.yml")) do |fh|
+          assert_equal(["second_welcome"], fh.each.map { |name, _| name })
         end
       end
 
       def test_extracts_model_class_from_config_row
-        File.open(::File.join(FIXTURES_ROOT, 'other_posts.yml')) do |fh|
-          assert_equal 'Post', fh.model_class
+        File.open(::File.join(FIXTURES_ROOT, "other_posts.yml")) do |fh|
+          assert_equal "Post", fh.model_class
         end
       end
 
       def test_erb_filename
-        filename = 'filename.yaml'
+        filename = "filename.yaml"
         erb = File.new(filename).send(:prepare_erb, "<% Rails.env %>\n")
         assert_equal erb.filename, filename
       end
 
       private
-      def tmp_yaml(name, contents)
-        t = Tempfile.new name
-        t.binmode
-        t.write contents
-        t.close
-        yield t
-      ensure
-        t.close true
-      end
+        def tmp_yaml(name, contents)
+          t = Tempfile.new name
+          t.binmode
+          t.write contents
+          t.close
+          yield t
+        ensure
+          t.close true
+        end
     end
   end
 end
diff --git a/activerecord/test/cases/fixtures_test.rb b/activerecord/test/cases/fixtures_test.rb
index 9455d4886c..8e8a49af8e 100644
--- a/activerecord/test/cases/fixtures_test.rb
+++ b/activerecord/test/cases/fixtures_test.rb
@@ -1,31 +1,35 @@
-require 'cases/helper'
-require 'models/admin'
-require 'models/admin/account'
-require 'models/admin/randomly_named_c1'
-require 'models/admin/user'
-require 'models/binary'
-require 'models/book'
-require 'models/bulb'
-require 'models/category'
-require 'models/comment'
-require 'models/company'
-require 'models/computer'
-require 'models/course'
-require 'models/developer'
-require 'models/doubloon'
-require 'models/joke'
-require 'models/matey'
-require 'models/parrot'
-require 'models/pirate'
-require 'models/post'
-require 'models/randomly_named_c1'
-require 'models/reply'
-require 'models/ship'
-require 'models/task'
-require 'models/topic'
-require 'models/traffic_light'
-require 'models/treasure'
-require 'tempfile'
+# frozen_string_literal: true
+
+require "cases/helper"
+require "models/admin"
+require "models/admin/account"
+require "models/admin/randomly_named_c1"
+require "models/admin/user"
+require "models/binary"
+require "models/book"
+require "models/bulb"
+require "models/category"
+require "models/post"
+require "models/comment"
+require "models/company"
+require "models/computer"
+require "models/course"
+require "models/developer"
+require "models/dog"
+require "models/doubloon"
+require "models/joke"
+require "models/matey"
+require "models/other_dog"
+require "models/parrot"
+require "models/pirate"
+require "models/randomly_named_c1"
+require "models/reply"
+require "models/ship"
+require "models/task"
+require "models/topic"
+require "models/traffic_light"
+require "models/treasure"
+require "tempfile"
 
 class FixturesTest < ActiveRecord::TestCase
   self.use_instantiated_fixtures = true
@@ -52,13 +56,38 @@ class FixturesTest < ActiveRecord::TestCase
     end
   end
 
+  class InsertQuerySubscriber
+    attr_reader :events
+
+    def initialize
+      @events = []
+    end
+
+    def call(_, _, _, _, values)
+      @events << values[:sql] if values[:sql] =~ /INSERT/
+    end
+  end
+
+  if current_adapter?(:Mysql2Adapter, :PostgreSQLAdapter)
+    def test_bulk_insert
+      begin
+        subscriber = InsertQuerySubscriber.new
+        subscription = ActiveSupport::Notifications.subscribe("sql.active_record", subscriber)
+        create_fixtures("bulbs")
+        assert_equal 1, subscriber.events.size, "It takes one INSERT query to insert two fixtures"
+      ensure
+        ActiveSupport::Notifications.unsubscribe(subscription)
+      end
+    end
+  end
+
   def test_broken_yaml_exception
-    badyaml = Tempfile.new ['foo', '.yml']
-    badyaml.write 'a: : '
+    badyaml = Tempfile.new ["foo", ".yml"]
+    badyaml.write "a: : "
     badyaml.flush
 
     dir  = File.dirname badyaml.path
-    name = File.basename badyaml.path, '.yml'
+    name = File.basename badyaml.path, ".yml"
     assert_raises(ActiveRecord::Fixture::FormatError) do
       ActiveRecord::FixtureSet.create_fixtures(dir, name)
     end
@@ -69,8 +98,8 @@ class FixturesTest < ActiveRecord::TestCase
 
   def test_create_fixtures
     fixtures = ActiveRecord::FixtureSet.create_fixtures(FIXTURES_ROOT, "parrots")
-    assert Parrot.find_by_name('Curious George'), 'George is not in the database'
-    assert fixtures.detect { |f| f.name == 'parrots' }, "no fixtures named 'parrots' in #{fixtures.map(&:name).inspect}"
+    assert Parrot.find_by_name("Curious George"), "George is not in the database"
+    assert fixtures.detect { |f| f.name == "parrots" }, "no fixtures named 'parrots' in #{fixtures.map(&:name).inspect}"
   end
 
   def test_multiple_clean_fixtures
@@ -81,10 +110,10 @@ class FixturesTest < ActiveRecord::TestCase
   end
 
   def test_create_symbol_fixtures
-    fixtures = ActiveRecord::FixtureSet.create_fixtures(FIXTURES_ROOT, :collections, :collections => Course) { Course.connection }
+    fixtures = ActiveRecord::FixtureSet.create_fixtures(FIXTURES_ROOT, :collections, collections: Course) { Course.connection }
 
-    assert Course.find_by_name('Collection'), 'course is not in the database'
-    assert fixtures.detect { |f| f.name == 'collections' }, "no fixtures named 'collections' in #{fixtures.map(&:name).inspect}"
+    assert Course.find_by_name("Collection"), "course is not in the database"
+    assert fixtures.detect { |f| f.name == "collections" }, "no fixtures named 'collections' in #{fixtures.map(&:name).inspect}"
   end
 
   def test_attributes
@@ -93,6 +122,24 @@ class FixturesTest < ActiveRecord::TestCase
     assert_nil(topics["second"]["author_email_address"])
   end
 
+  def test_no_args_returns_all
+    all_topics = topics
+    assert_equal 5, all_topics.length
+    assert_equal "The First Topic", all_topics.first["title"]
+    assert_equal 5, all_topics.last.id
+  end
+
+  def test_no_args_record_returns_all_without_array
+    all_binaries = binaries
+    assert_kind_of(Array, all_binaries)
+    assert_equal 2, binaries.length
+  end
+
+  def test_nil_raises
+    assert_raise(StandardError) { topics(nil) }
+    assert_raise(StandardError) { topics([nil]) }
+  end
+
   def test_inserts
     create_fixtures("topics")
     first_row = ActiveRecord::Base.connection.select_one("SELECT * FROM topics WHERE author_name = 'David'")
@@ -102,64 +149,62 @@ class FixturesTest < ActiveRecord::TestCase
     assert_nil(second_row["author_email_address"])
   end
 
-  if ActiveRecord::Base.connection.supports_migrations?
-    def test_inserts_with_pre_and_suffix
-      # Reset cache to make finds on the new table work
-      ActiveRecord::FixtureSet.reset_cache
-
-      ActiveRecord::Base.connection.create_table :prefix_other_topics_suffix do |t|
-        t.column :title, :string
-        t.column :author_name, :string
-        t.column :author_email_address, :string
-        t.column :written_on, :datetime
-        t.column :bonus_time, :time
-        t.column :last_read, :date
-        t.column :content, :string
-        t.column :approved, :boolean, :default => true
-        t.column :replies_count, :integer, :default => 0
-        t.column :parent_id, :integer
-        t.column :type, :string, :limit => 50
-      end
+  def test_inserts_with_pre_and_suffix
+    # Reset cache to make finds on the new table work
+    ActiveRecord::FixtureSet.reset_cache
 
-      # Store existing prefix/suffix
-      old_prefix = ActiveRecord::Base.table_name_prefix
-      old_suffix = ActiveRecord::Base.table_name_suffix
+    ActiveRecord::Base.connection.create_table :prefix_other_topics_suffix do |t|
+      t.column :title, :string
+      t.column :author_name, :string
+      t.column :author_email_address, :string
+      t.column :written_on, :datetime
+      t.column :bonus_time, :time
+      t.column :last_read, :date
+      t.column :content, :string
+      t.column :approved, :boolean, default: true
+      t.column :replies_count, :integer, default: 0
+      t.column :parent_id, :integer
+      t.column :type, :string, limit: 50
+    end
 
-      # Set a prefix/suffix we can test against
-      ActiveRecord::Base.table_name_prefix = 'prefix_'
-      ActiveRecord::Base.table_name_suffix = '_suffix'
+    # Store existing prefix/suffix
+    old_prefix = ActiveRecord::Base.table_name_prefix
+    old_suffix = ActiveRecord::Base.table_name_suffix
 
-      other_topic_klass = Class.new(ActiveRecord::Base) do
-        def self.name
-          "OtherTopic"
-        end
+    # Set a prefix/suffix we can test against
+    ActiveRecord::Base.table_name_prefix = "prefix_"
+    ActiveRecord::Base.table_name_suffix = "_suffix"
+
+    other_topic_klass = Class.new(ActiveRecord::Base) do
+      def self.name
+        "OtherTopic"
       end
+    end
 
-      topics = [create_fixtures("other_topics")].flatten.first
+    topics = [create_fixtures("other_topics")].flatten.first
 
-      # This checks for a caching problem which causes a bug in the fixtures
-      # class-level configuration helper.
-      assert_not_nil topics, "Fixture data inserted, but fixture objects not returned from create"
+    # This checks for a caching problem which causes a bug in the fixtures
+    # class-level configuration helper.
+    assert_not_nil topics, "Fixture data inserted, but fixture objects not returned from create"
 
-      first_row = ActiveRecord::Base.connection.select_one("SELECT * FROM prefix_other_topics_suffix WHERE author_name = 'David'")
-      assert_not_nil first_row, "The prefix_other_topics_suffix table appears to be empty despite create_fixtures: the row with author_name = 'David' was not found"
-      assert_equal("The First Topic", first_row["title"])
+    first_row = ActiveRecord::Base.connection.select_one("SELECT * FROM prefix_other_topics_suffix WHERE author_name = 'David'")
+    assert_not_nil first_row, "The prefix_other_topics_suffix table appears to be empty despite create_fixtures: the row with author_name = 'David' was not found"
+    assert_equal("The First Topic", first_row["title"])
 
-      second_row = ActiveRecord::Base.connection.select_one("SELECT * FROM prefix_other_topics_suffix WHERE author_name = 'Mary'")
-      assert_nil(second_row["author_email_address"])
+    second_row = ActiveRecord::Base.connection.select_one("SELECT * FROM prefix_other_topics_suffix WHERE author_name = 'Mary'")
+    assert_nil(second_row["author_email_address"])
 
-      assert_equal :prefix_other_topics_suffix, topics.table_name.to_sym
-      # This assertion should preferably be the last in the list, because calling
-      # other_topic_klass.table_name sets a class-level instance variable
-      assert_equal :prefix_other_topics_suffix, other_topic_klass.table_name.to_sym
+    assert_equal :prefix_other_topics_suffix, topics.table_name.to_sym
+    # This assertion should preferably be the last in the list, because calling
+    # other_topic_klass.table_name sets a class-level instance variable
+    assert_equal :prefix_other_topics_suffix, other_topic_klass.table_name.to_sym
 
-    ensure
-      # Restore prefix/suffix to its previous values
-      ActiveRecord::Base.table_name_prefix = old_prefix
-      ActiveRecord::Base.table_name_suffix = old_suffix
+  ensure
+    # Restore prefix/suffix to its previous values
+    ActiveRecord::Base.table_name_prefix = old_prefix
+    ActiveRecord::Base.table_name_suffix = old_suffix
 
-      ActiveRecord::Base.connection.drop_table :prefix_other_topics_suffix rescue nil
-    end
+    ActiveRecord::Base.connection.drop_table :prefix_other_topics_suffix rescue nil
   end
 
   def test_insert_with_datetime
@@ -170,7 +215,7 @@ class FixturesTest < ActiveRecord::TestCase
 
   def test_logger_level_invariant
     level = ActiveRecord::Base.logger.level
-    create_fixtures('topics')
+    create_fixtures("topics")
     assert_equal level, ActiveRecord::Base.logger.level
   end
 
@@ -192,35 +237,50 @@ class FixturesTest < ActiveRecord::TestCase
   end
 
   def test_empty_yaml_fixture
-    assert_not_nil ActiveRecord::FixtureSet.new( Account.connection, "accounts", Account, FIXTURES_ROOT + "/naked/yml/accounts")
+    assert_not_nil ActiveRecord::FixtureSet.new(Account.connection, "accounts", Account, FIXTURES_ROOT + "/naked/yml/accounts")
   end
 
   def test_empty_yaml_fixture_with_a_comment_in_it
-    assert_not_nil ActiveRecord::FixtureSet.new( Account.connection, "companies", Company, FIXTURES_ROOT + "/naked/yml/companies")
+    assert_not_nil ActiveRecord::FixtureSet.new(Account.connection, "companies", Company, FIXTURES_ROOT + "/naked/yml/companies")
   end
 
   def test_nonexistent_fixture_file
     nonexistent_fixture_path = FIXTURES_ROOT + "/imnothere"
 
-    #sanity check to make sure that this file never exists
-    assert Dir[nonexistent_fixture_path+"*"].empty?
+    # sanity check to make sure that this file never exists
+    assert Dir[nonexistent_fixture_path + "*"].empty?
 
     assert_raise(Errno::ENOENT) do
-      ActiveRecord::FixtureSet.new( Account.connection, "companies", Company, nonexistent_fixture_path)
+      ActiveRecord::FixtureSet.new(Account.connection, "companies", Company, nonexistent_fixture_path)
     end
   end
 
   def test_dirty_dirty_yaml_file
-    assert_raise(ActiveRecord::Fixture::FormatError) do
-      ActiveRecord::FixtureSet.new( Account.connection, "courses", Course, FIXTURES_ROOT + "/naked/yml/courses")
+    fixture_path = FIXTURES_ROOT + "/naked/yml/courses"
+    error = assert_raise(ActiveRecord::Fixture::FormatError) do
+      ActiveRecord::FixtureSet.new(Account.connection, "courses", Course, fixture_path)
     end
+    assert_equal "fixture is not a hash: #{fixture_path}.yml", error.to_s
+  end
+
+  def test_yaml_file_with_one_invalid_fixture
+    fixture_path = FIXTURES_ROOT + "/naked/yml/courses_with_invalid_key"
+    error = assert_raise(ActiveRecord::Fixture::FormatError) do
+      ActiveRecord::FixtureSet.new(Account.connection, "courses", Course, fixture_path)
+    end
+    assert_equal "fixture key is not a hash: #{fixture_path}.yml, keys: [\"two\"]", error.to_s
   end
 
   def test_yaml_file_with_invalid_column
     e = assert_raise(ActiveRecord::Fixture::FixtureError) do
       ActiveRecord::FixtureSet.create_fixtures(FIXTURES_ROOT + "/naked/yml", "parrots")
     end
-    assert_equal(%(table "parrots" has no column named "arrr".), e.message)
+
+    if current_adapter?(:SQLite3Adapter)
+      assert_equal(%(table "parrots" has no column named "arrr".), e.message)
+    else
+      assert_equal(%(table "parrots" has no columns named "arrr", "foobar".), e.message)
+    end
   end
 
   def test_yaml_file_with_symbol_columns
@@ -229,11 +289,11 @@ class FixturesTest < ActiveRecord::TestCase
 
   def test_omap_fixtures
     assert_nothing_raised do
-      fixtures = ActiveRecord::FixtureSet.new(Account.connection, 'categories', Category, FIXTURES_ROOT + "/categories_ordered")
+      fixtures = ActiveRecord::FixtureSet.new(Account.connection, "categories", Category, FIXTURES_ROOT + "/categories_ordered")
 
       fixtures.each.with_index do |(name, fixture), i|
         assert_equal "fixture_no_#{i}", name
-        assert_equal "Category #{i}", fixture['name']
+        assert_equal "Category #{i}", fixture["name"]
       end
     end
   end
@@ -249,10 +309,11 @@ class FixturesTest < ActiveRecord::TestCase
   end
 
   def test_binary_in_fixtures
-    data = File.open(ASSETS_ROOT + "/flowers.jpg", 'rb') { |f| f.read }
-    data.force_encoding('ASCII-8BIT')
+    data = File.open(ASSETS_ROOT + "/flowers.jpg", "rb") { |f| f.read }
+    data.force_encoding("ASCII-8BIT")
     data.freeze
     assert_equal data, @flowers.data
+    assert_equal data, @binary_helper.data
   end
 
   def test_serialized_fixtures
@@ -260,8 +321,8 @@ class FixturesTest < ActiveRecord::TestCase
   end
 
   def test_fixtures_are_set_up_with_database_env_variable
-    db_url_tmp = ENV['DATABASE_URL']
-    ENV['DATABASE_URL'] = "sqlite3::memory:"
+    db_url_tmp = ENV["DATABASE_URL"]
+    ENV["DATABASE_URL"] = "sqlite3::memory:"
     ActiveRecord::Base.stub(:configurations, {}) do
       test_case = Class.new(ActiveRecord::TestCase) do
         fixtures :accounts
@@ -276,11 +337,11 @@ class FixturesTest < ActiveRecord::TestCase
       assert result.passed?, "Expected #{result.name} to pass:\n#{result}"
     end
   ensure
-    ENV['DATABASE_URL'] = db_url_tmp
+    ENV["DATABASE_URL"] = db_url_tmp
   end
 end
 
-class HasManyThroughFixture < ActiveSupport::TestCase
+class HasManyThroughFixture < ActiveRecord::TestCase
   def make_model(name)
     Class.new(ActiveRecord::Base) { define_singleton_method(:name) { name } }
   end
@@ -291,17 +352,17 @@ class HasManyThroughFixture < ActiveSupport::TestCase
     treasure = make_model "Treasure"
 
     pt.table_name = "parrots_treasures"
-    pt.belongs_to :parrot, :anonymous_class => parrot
-    pt.belongs_to :treasure, :anonymous_class => treasure
+    pt.belongs_to :parrot, anonymous_class: parrot
+    pt.belongs_to :treasure, anonymous_class: treasure
 
-    parrot.has_many :parrot_treasures, :anonymous_class => pt
-    parrot.has_many :treasures, :through => :parrot_treasures
+    parrot.has_many :parrot_treasures, anonymous_class: pt
+    parrot.has_many :treasures, through: :parrot_treasures
 
-    parrots = File.join FIXTURES_ROOT, 'parrots'
+    parrots = File.join FIXTURES_ROOT, "parrots"
 
     fs = ActiveRecord::FixtureSet.new parrot.connection, "parrots", parrot, parrots
     rows = fs.table_rows
-    assert_equal load_has_and_belongs_to_many['parrots_treasures'], rows['parrots_treasures']
+    assert_equal load_has_and_belongs_to_many["parrots_treasures"], rows["parrots_treasures"]
   end
 
   def test_has_many_through_with_renamed_table
@@ -309,24 +370,24 @@ class HasManyThroughFixture < ActiveSupport::TestCase
     parrot = make_model "Parrot"
     treasure = make_model "Treasure"
 
-    pt.belongs_to :parrot, :anonymous_class => parrot
-    pt.belongs_to :treasure, :anonymous_class => treasure
+    pt.belongs_to :parrot, anonymous_class: parrot
+    pt.belongs_to :treasure, anonymous_class: treasure
 
-    parrot.has_many :parrot_treasures, :anonymous_class => pt
-    parrot.has_many :treasures, :through => :parrot_treasures
+    parrot.has_many :parrot_treasures, anonymous_class: pt
+    parrot.has_many :treasures, through: :parrot_treasures
 
-    parrots = File.join FIXTURES_ROOT, 'parrots'
+    parrots = File.join FIXTURES_ROOT, "parrots"
 
     fs = ActiveRecord::FixtureSet.new parrot.connection, "parrots", parrot, parrots
     rows = fs.table_rows
-    assert_equal load_has_and_belongs_to_many['parrots_treasures'], rows['parrot_treasures']
+    assert_equal load_has_and_belongs_to_many["parrots_treasures"], rows["parrot_treasures"]
   end
 
   def load_has_and_belongs_to_many
     parrot = make_model "Parrot"
     parrot.has_and_belongs_to_many :treasures
 
-    parrots = File.join FIXTURES_ROOT, 'parrots'
+    parrots = File.join FIXTURES_ROOT, "parrots"
 
     fs = ActiveRecord::FixtureSet.new parrot.connection, "parrots", parrot, parrots
     fs.table_rows
@@ -337,9 +398,10 @@ if Account.connection.respond_to?(:reset_pk_sequence!)
   class FixturesResetPkSequenceTest < ActiveRecord::TestCase
     fixtures :accounts
     fixtures :companies
+    self.use_transactional_tests = false
 
     def setup
-      @instances = [Account.new(:credit_limit => 50), Company.new(:name => 'RoR Consulting'), Course.new(name: 'Test')]
+      @instances = [Account.new(credit_limit: 50), Company.new(name: "RoR Consulting"), Course.new(name: "Test")]
       ActiveRecord::FixtureSet.reset_cache # make sure tables get reinitialized
     end
 
@@ -368,7 +430,7 @@ if Account.connection.respond_to?(:reset_pk_sequence!)
     def test_create_fixtures_resets_sequences_when_not_cached
       @instances.each do |instance|
         max_id = create_fixtures(instance.class.table_name).first.fixtures.inject(0) do |_max_id, (_, fixture)|
-          fixture_id = fixture['id'].to_i
+          fixture_id = fixture["id"].to_i
           fixture_id > _max_id ? fixture_id : _max_id
         end
 
@@ -414,7 +476,7 @@ class FixturesWithoutInstantiationTest < ActiveRecord::TestCase
   def test_reloading_fixtures_through_accessor_methods
     topic = Struct.new(:title)
     assert_equal "The First Topic", topics(:first).title
-    assert_called(@loaded_fixtures['topics']['first'], :find, returns: topic.new("Fresh Topic!")) do
+    assert_called(@loaded_fixtures["topics"]["first"], :find, returns: topic.new("Fresh Topic!")) do
       assert_equal "Fresh Topic!", topics(:first, true).title
     end
   end
@@ -479,7 +541,6 @@ class SetupSubclassTest < SetupTest
   end
 end
 
-
 class OverlappingFixturesTest < ActiveRecord::TestCase
   fixtures :topics, :developers
   fixtures :developers, :accounts
@@ -510,13 +571,13 @@ class OverRideFixtureMethodTest < ActiveRecord::TestCase
 
   def topics(name)
     topic = super
-    topic.title = 'omg'
+    topic.title = "omg"
     topic
   end
 
   def test_fixture_methods_can_be_overridden
     x = topics :first
-    assert_equal 'omg', x.title
+    assert_equal "omg", x.title
   end
 end
 
@@ -553,7 +614,7 @@ class SetFixtureClassPrevailsTest < ActiveRecord::TestCase
 end
 
 class CheckSetTableNameFixturesTest < ActiveRecord::TestCase
-  set_fixture_class :funny_jokes => Joke
+  set_fixture_class funny_jokes: Joke
   fixtures :funny_jokes
   # Set to false to blow away fixtures cache and ensure our fixtures are loaded
   # and thus takes into account our set_fixture_class
@@ -565,7 +626,7 @@ class CheckSetTableNameFixturesTest < ActiveRecord::TestCase
 end
 
 class FixtureNameIsNotTableNameFixturesTest < ActiveRecord::TestCase
-  set_fixture_class :items => Book
+  set_fixture_class items: Book
   fixtures :items
   # Set to false to blow away fixtures cache and ensure our fixtures are loaded
   # and thus takes into account our set_fixture_class
@@ -577,7 +638,7 @@ class FixtureNameIsNotTableNameFixturesTest < ActiveRecord::TestCase
 end
 
 class FixtureNameIsNotTableNameMultipleFixturesTest < ActiveRecord::TestCase
-  set_fixture_class :items => Book, :funny_jokes => Joke
+  set_fixture_class items: Book, funny_jokes: Joke
   fixtures :items, :funny_jokes
   # Set to false to blow away fixtures cache and ensure our fixtures are loaded
   # and thus takes into account our set_fixture_class
@@ -593,7 +654,7 @@ class FixtureNameIsNotTableNameMultipleFixturesTest < ActiveRecord::TestCase
 end
 
 class CustomConnectionFixturesTest < ActiveRecord::TestCase
-  set_fixture_class :courses => Course
+  set_fixture_class courses: Course
   fixtures :courses
   self.use_transactional_tests = false
 
@@ -608,7 +669,7 @@ class CustomConnectionFixturesTest < ActiveRecord::TestCase
 end
 
 class TransactionalFixturesOnCustomConnectionTest < ActiveRecord::TestCase
-  set_fixture_class :courses => Course
+  set_fixture_class courses: Course
   fixtures :courses
   self.use_transactional_tests = true
 
@@ -622,6 +683,52 @@ class TransactionalFixturesOnCustomConnectionTest < ActiveRecord::TestCase
   end
 end
 
+class TransactionalFixturesOnConnectionNotification < ActiveRecord::TestCase
+  self.use_transactional_tests = true
+  self.use_instantiated_fixtures = false
+
+  def test_transaction_created_on_connection_notification
+    connection = stub(transaction_open?: false)
+    connection.expects(:begin_transaction).with(joinable: false)
+    pool = connection.stubs(:pool).returns(ActiveRecord::ConnectionAdapters::ConnectionPool.new(ActiveRecord::Base.connection_pool.spec))
+    pool.stubs(:lock_thread=).with(false)
+    fire_connection_notification(connection)
+  end
+
+  def test_notification_established_transactions_are_rolled_back
+    # Mocha is not thread-safe so define our own stub to test
+    connection = Class.new do
+      attr_accessor :rollback_transaction_called
+      attr_accessor :pool
+      def transaction_open?; true; end
+      def begin_transaction(*args); end
+      def rollback_transaction(*args)
+        @rollback_transaction_called = true
+      end
+    end.new
+    connection.pool = Class.new do
+      def lock_thread=(lock_thread); false; end
+    end.new
+    fire_connection_notification(connection)
+    teardown_fixtures
+    assert(connection.rollback_transaction_called, "Expected <mock connection>#rollback_transaction to be called but was not")
+  end
+
+  private
+
+    def fire_connection_notification(connection)
+      ActiveRecord::Base.connection_handler.stubs(:retrieve_connection).with("book").returns(connection)
+      message_bus = ActiveSupport::Notifications.instrumenter
+      payload = {
+        spec_name: "book",
+        config: nil,
+        connection_id: connection.object_id
+      }
+
+      message_bus.instrument("!connection.active_record", payload) {}
+    end
+end
+
 class InvalidTableNameFixturesTest < ActiveRecord::TestCase
   fixtures :funny_jokes
   # Set to false to blow away fixtures cache and ensure our fixtures are loaded
@@ -636,7 +743,7 @@ class InvalidTableNameFixturesTest < ActiveRecord::TestCase
 end
 
 class CheckEscapedYamlFixturesTest < ActiveRecord::TestCase
-  set_fixture_class :funny_jokes => Joke
+  set_fixture_class funny_jokes: Joke
   fixtures :funny_jokes
   # Set to false to blow away fixtures cache and ensure our fixtures are loaded
   # and thus takes into account our set_fixture_class
@@ -679,7 +786,7 @@ class FixturesBrokenRollbackTest < ActiveRecord::TestCase
 
   private
     def load_fixtures(config)
-      raise 'argh'
+      raise "argh"
     end
 end
 
@@ -689,7 +796,7 @@ class LoadAllFixturesTest < ActiveRecord::TestCase
     self.class.fixtures :all
 
     if File.symlink? FIXTURES_ROOT + "/all/admin"
-      assert_equal %w(admin/accounts admin/users developers people tasks), fixture_table_names.sort
+      assert_equal %w(admin/accounts admin/users developers namespaced/accounts people tasks), fixture_table_names.sort
     end
   ensure
     ActiveRecord::FixtureSet.reset_cache
@@ -698,11 +805,11 @@ end
 
 class LoadAllFixturesWithPathnameTest < ActiveRecord::TestCase
   def test_all_there
-    self.class.fixture_path = Pathname.new(FIXTURES_ROOT).join('all')
+    self.class.fixture_path = Pathname.new(FIXTURES_ROOT).join("all")
     self.class.fixtures :all
 
     if File.symlink? FIXTURES_ROOT + "/all/admin"
-      assert_equal %w(admin/accounts admin/users developers people tasks), fixture_table_names.sort
+      assert_equal %w(admin/accounts admin/users developers namespaced/accounts people tasks), fixture_table_names.sort
     end
   ensure
     ActiveRecord::FixtureSet.reset_cache
@@ -711,7 +818,7 @@ end
 
 class FasterFixturesTest < ActiveRecord::TestCase
   self.use_transactional_tests = false
-  fixtures :categories, :authors
+  fixtures :categories, :authors, :author_addresses
 
   def load_extra_fixture(name)
     fixture = create_fixtures(name).first
@@ -720,28 +827,30 @@ class FasterFixturesTest < ActiveRecord::TestCase
   end
 
   def test_cache
-    assert ActiveRecord::FixtureSet.fixture_is_cached?(ActiveRecord::Base.connection, 'categories')
-    assert ActiveRecord::FixtureSet.fixture_is_cached?(ActiveRecord::Base.connection, 'authors')
+    assert ActiveRecord::FixtureSet.fixture_is_cached?(ActiveRecord::Base.connection, "categories")
+    assert ActiveRecord::FixtureSet.fixture_is_cached?(ActiveRecord::Base.connection, "authors")
 
     assert_no_queries do
-      create_fixtures('categories')
-      create_fixtures('authors')
+      create_fixtures("categories")
+      create_fixtures("authors")
     end
 
-    load_extra_fixture('posts')
-    assert ActiveRecord::FixtureSet.fixture_is_cached?(ActiveRecord::Base.connection, 'posts')
+    load_extra_fixture("posts")
+    assert ActiveRecord::FixtureSet.fixture_is_cached?(ActiveRecord::Base.connection, "posts")
     self.class.setup_fixture_accessors :posts
-    assert_equal 'Welcome to the weblog', posts(:welcome).title
+    assert_equal "Welcome to the weblog", posts(:welcome).title
   end
 end
 
 class FoxyFixturesTest < ActiveRecord::TestCase
+  # Set to false to blow away fixtures cache and ensure our fixtures are loaded
+  self.use_transactional_tests = false
   fixtures :parrots, :parrots_pirates, :pirates, :treasures, :mateys, :ships, :computers,
            :developers, :"admin/accounts", :"admin/users", :live_parrots, :dead_parrots, :books
 
-  if ActiveRecord::Base.connection.adapter_name == 'PostgreSQL'
-    require 'models/uuid_parent'
-    require 'models/uuid_child'
+  if ActiveRecord::Base.connection.adapter_name == "PostgreSQL"
+    require "models/uuid_parent"
+    require "models/uuid_child"
     fixtures :uuid_parents, :uuid_children
   end
 
@@ -758,8 +867,8 @@ class FoxyFixturesTest < ActiveRecord::TestCase
     assert_equal 207281424, ActiveRecord::FixtureSet.identify(:ruby)
     assert_equal 1066363776, ActiveRecord::FixtureSet.identify(:sapphire_2)
 
-    assert_equal 'f92b6bda-0d0d-5fe1-9124-502b18badded', ActiveRecord::FixtureSet.identify(:daddy, :uuid)
-    assert_equal 'b4b10018-ad47-595d-b42f-d8bdaa6d01bf', ActiveRecord::FixtureSet.identify(:sonny, :uuid)
+    assert_equal "f92b6bda-0d0d-5fe1-9124-502b18badded", ActiveRecord::FixtureSet.identify(:daddy, :uuid)
+    assert_equal "b4b10018-ad47-595d-b42f-d8bdaa6d01bf", ActiveRecord::FixtureSet.identify(:sonny, :uuid)
   end
 
   TIMESTAMP_COLUMNS = %w(created_at created_on updated_at updated_on)
@@ -884,7 +993,7 @@ class FoxyFixturesTest < ActiveRecord::TestCase
   end
 
   def test_namespaced_models
-    assert admin_accounts(:signals37).users.include?(admin_users(:david))
+    assert_includes admin_accounts(:signals37).users, admin_users(:david)
     assert_equal 2, admin_accounts(:signals37).users.size
   end
 
@@ -909,14 +1018,14 @@ end
 class CustomNameForFixtureOrModelTest < ActiveRecord::TestCase
   ActiveRecord::FixtureSet.reset_cache
 
-  set_fixture_class :randomly_named_a9         =>
+  set_fixture_class :randomly_named_a9 =>
                         ClassNameThatDoesNotFollowCONVENTIONS,
                     :'admin/randomly_named_a9' =>
                         Admin::ClassNameThatDoesNotFollowCONVENTIONS1,
-                    'admin/randomly_named_b0'  =>
+                    "admin/randomly_named_b0"  =>
                         Admin::ClassNameThatDoesNotFollowCONVENTIONS2
 
-  fixtures :randomly_named_a9, 'admin/randomly_named_a9',
+  fixtures :randomly_named_a9, "admin/randomly_named_a9",
            :'admin/randomly_named_b0'
 
   def test_named_accessor_for_randomly_named_fixture_and_class
@@ -932,8 +1041,8 @@ class CustomNameForFixtureOrModelTest < ActiveRecord::TestCase
   end
 
   def test_table_name_is_defined_in_the_model
-    assert_equal 'randomly_named_table2', ActiveRecord::FixtureSet::all_loaded_fixtures["admin/randomly_named_a9"].table_name
-    assert_equal 'randomly_named_table2', Admin::ClassNameThatDoesNotFollowCONVENTIONS1.table_name
+    assert_equal "randomly_named_table2", ActiveRecord::FixtureSet::all_loaded_fixtures["admin/randomly_named_a9"].table_name
+    assert_equal "randomly_named_table2", Admin::ClassNameThatDoesNotFollowCONVENTIONS1.table_name
   end
 end
 
@@ -961,14 +1070,27 @@ end
 
 class FixtureClassNamesTest < ActiveRecord::TestCase
   def setup
-    @saved_cache = self.fixture_class_names.dup
+    @saved_cache = fixture_class_names.dup
   end
 
   def teardown
-    self.fixture_class_names.replace(@saved_cache)
+    fixture_class_names.replace(@saved_cache)
   end
 
   test "fixture_class_names returns nil for unregistered identifier" do
-    assert_nil self.fixture_class_names['unregistered_identifier']
+    assert_nil fixture_class_names["unregistered_identifier"]
+  end
+end
+
+class SameNameDifferentDatabaseFixturesTest < ActiveRecord::TestCase
+  fixtures :dogs, :other_dogs
+
+  test "fixtures are properly loaded" do
+    # Force loading the fixtures again to reproduce issue
+    ActiveRecord::FixtureSet.reset_cache
+    create_fixtures("dogs", "other_dogs")
+
+    assert_kind_of Dog, dogs(:sophie)
+    assert_kind_of OtherDog, other_dogs(:lassie)
   end
 end
diff --git a/activerecord/test/cases/forbidden_attributes_protection_test.rb b/activerecord/test/cases/forbidden_attributes_protection_test.rb
index 91921469b8..101fa118c8 100644
--- a/activerecord/test/cases/forbidden_attributes_protection_test.rb
+++ b/activerecord/test/cases/forbidden_attributes_protection_test.rb
@@ -1,11 +1,13 @@
-require 'cases/helper'
-require 'active_support/core_ext/hash/indifferent_access'
+# frozen_string_literal: true
 
-require 'models/company'
-require 'models/person'
-require 'models/ship'
-require 'models/ship_part'
-require 'models/treasure'
+require "cases/helper"
+require "active_support/core_ext/hash/indifferent_access"
+
+require "models/company"
+require "models/person"
+require "models/ship"
+require "models/ship_part"
+require "models/treasure"
 
 class ProtectedParams
   attr_accessor :permitted
@@ -44,40 +46,40 @@ end
 
 class ForbiddenAttributesProtectionTest < ActiveRecord::TestCase
   def test_forbidden_attributes_cannot_be_used_for_mass_assignment
-    params = ProtectedParams.new(first_name: 'Guille', gender: 'm')
+    params = ProtectedParams.new(first_name: "Guille", gender: "m")
     assert_raises(ActiveModel::ForbiddenAttributesError) do
       Person.new(params)
     end
   end
 
   def test_permitted_attributes_can_be_used_for_mass_assignment
-    params = ProtectedParams.new(first_name: 'Guille', gender: 'm')
+    params = ProtectedParams.new(first_name: "Guille", gender: "m")
     params.permit!
     person = Person.new(params)
 
-    assert_equal 'Guille', person.first_name
-    assert_equal 'm', person.gender
+    assert_equal "Guille", person.first_name
+    assert_equal "m", person.gender
   end
 
   def test_forbidden_attributes_cannot_be_used_for_sti_inheritance_column
-    params = ProtectedParams.new(type: 'Client')
+    params = ProtectedParams.new(type: "Client")
     assert_raises(ActiveModel::ForbiddenAttributesError) do
       Company.new(params)
     end
   end
 
   def test_permitted_attributes_can_be_used_for_sti_inheritance_column
-    params = ProtectedParams.new(type: 'Client')
+    params = ProtectedParams.new(type: "Client")
     params.permit!
     person = Company.new(params)
     assert_equal person.class, Client
   end
 
   def test_regular_hash_should_still_be_used_for_mass_assignment
-    person = Person.new(first_name: 'Guille', gender: 'm')
+    person = Person.new(first_name: "Guille", gender: "m")
 
-    assert_equal 'Guille', person.first_name
-    assert_equal 'm', person.gender
+    assert_equal "Guille", person.first_name
+    assert_equal "m", person.gender
   end
 
   def test_blank_attributes_should_not_raise
@@ -86,7 +88,7 @@ class ForbiddenAttributesProtectionTest < ActiveRecord::TestCase
   end
 
   def test_create_with_checks_permitted
-    params = ProtectedParams.new(first_name: 'Guille', gender: 'm')
+    params = ProtectedParams.new(first_name: "Guille", gender: "m")
 
     assert_raises(ActiveModel::ForbiddenAttributesError) do
       Person.create_with(params).create!
@@ -94,21 +96,21 @@ class ForbiddenAttributesProtectionTest < ActiveRecord::TestCase
   end
 
   def test_create_with_works_with_permitted_params
-    params = ProtectedParams.new(first_name: 'Guille').permit!
+    params = ProtectedParams.new(first_name: "Guille").permit!
 
     person = Person.create_with(params).create!
-    assert_equal 'Guille', person.first_name
+    assert_equal "Guille", person.first_name
   end
 
   def test_create_with_works_with_params_values
-    params = ProtectedParams.new(first_name: 'Guille')
+    params = ProtectedParams.new(first_name: "Guille")
 
     person = Person.create_with(first_name: params[:first_name]).create!
-    assert_equal 'Guille', person.first_name
+    assert_equal "Guille", person.first_name
   end
 
   def test_where_checks_permitted
-    params = ProtectedParams.new(first_name: 'Guille', gender: 'm')
+    params = ProtectedParams.new(first_name: "Guille", gender: "m")
 
     assert_raises(ActiveModel::ForbiddenAttributesError) do
       Person.where(params).create!
@@ -116,21 +118,21 @@ class ForbiddenAttributesProtectionTest < ActiveRecord::TestCase
   end
 
   def test_where_works_with_permitted_params
-    params = ProtectedParams.new(first_name: 'Guille').permit!
+    params = ProtectedParams.new(first_name: "Guille").permit!
 
     person = Person.where(params).create!
-    assert_equal 'Guille', person.first_name
+    assert_equal "Guille", person.first_name
   end
 
   def test_where_works_with_params_values
-    params = ProtectedParams.new(first_name: 'Guille')
+    params = ProtectedParams.new(first_name: "Guille")
 
     person = Person.where(first_name: params[:first_name]).create!
-    assert_equal 'Guille', person.first_name
+    assert_equal "Guille", person.first_name
   end
 
   def test_where_not_checks_permitted
-    params = ProtectedParams.new(first_name: 'Guille', gender: 'm')
+    params = ProtectedParams.new(first_name: "Guille", gender: "m")
 
     assert_raises(ActiveModel::ForbiddenAttributesError) do
       Person.where().not(params)
@@ -138,13 +140,13 @@ class ForbiddenAttributesProtectionTest < ActiveRecord::TestCase
   end
 
   def test_where_not_works_with_permitted_params
-    params = ProtectedParams.new(first_name: 'Guille').permit!
+    params = ProtectedParams.new(first_name: "Guille").permit!
     Person.create!(params)
-    assert_empty Person.where.not(params).select {|p| p.first_name == 'Guille' }
+    assert_empty Person.where.not(params).select { |p| p.first_name == "Guille" }
   end
 
   def test_strong_params_style_objects_work_with_singular_associations
-    params = ProtectedParams.new( name: "Stern", ship_attributes: ProtectedParams.new(name: "The Black Rock").permit!).permit!
+    params = ProtectedParams.new(name: "Stern", ship_attributes: ProtectedParams.new(name: "The Black Rock").permit!).permit!
     part = ShipPart.new(params)
 
     assert_equal "Stern", part.name
@@ -155,11 +157,10 @@ class ForbiddenAttributesProtectionTest < ActiveRecord::TestCase
     params = ProtectedParams.new(
       trinkets_attributes: ProtectedParams.new(
         "0" => ProtectedParams.new(name: "Necklace").permit!,
-        "1" => ProtectedParams.new(name: "Spoon").permit! ) ).permit!
+        "1" => ProtectedParams.new(name: "Spoon").permit!)).permit!
     part = ShipPart.new(params)
 
     assert_equal "Necklace", part.trinkets[0].name
     assert_equal "Spoon", part.trinkets[1].name
   end
-
 end
diff --git a/activerecord/test/cases/habtm_destroy_order_test.rb b/activerecord/test/cases/habtm_destroy_order_test.rb
index 2ce0de360e..5e503272e1 100644
--- a/activerecord/test/cases/habtm_destroy_order_test.rb
+++ b/activerecord/test/cases/habtm_destroy_order_test.rb
@@ -1,24 +1,26 @@
+# frozen_string_literal: true
+
 require "cases/helper"
 require "models/lesson"
 require "models/student"
 
 class HabtmDestroyOrderTest < ActiveRecord::TestCase
   test "may not delete a lesson with students" do
-    sicp = Lesson.new(:name => "SICP")
-    ben = Student.new(:name => "Ben Bitdiddle")
+    sicp = Lesson.new(name: "SICP")
+    ben = Student.new(name: "Ben Bitdiddle")
     sicp.students << ben
     sicp.save!
     assert_raises LessonError do
-      assert_no_difference('Lesson.count') do
+      assert_no_difference("Lesson.count") do
         sicp.destroy
       end
     end
     assert !sicp.destroyed?
   end
 
-  test 'should not raise error if have foreign key in the join table' do
-    student = Student.new(:name => "Ben Bitdiddle")
-    lesson = Lesson.new(:name => "SICP")
+  test "should not raise error if have foreign key in the join table" do
+    student = Student.new(name: "Ben Bitdiddle")
+    lesson = Lesson.new(name: "SICP")
     lesson.students << student
     lesson.save!
     assert_nothing_raised do
@@ -29,8 +31,8 @@ class HabtmDestroyOrderTest < ActiveRecord::TestCase
   test "not destroying a student with lessons leaves student<=>lesson association intact" do
     # test a normal before_destroy doesn't destroy the habtm joins
     begin
-      sicp = Lesson.new(:name => "SICP")
-      ben = Student.new(:name => "Ben Bitdiddle")
+      sicp = Lesson.new(name: "SICP")
+      ben = Student.new(name: "Ben Bitdiddle")
       # add a before destroy to student
       Student.class_eval do
         before_destroy do
@@ -49,8 +51,8 @@ class HabtmDestroyOrderTest < ActiveRecord::TestCase
 
   test "not destroying a lesson with students leaves student<=>lesson association intact" do
     # test a more aggressive before_destroy  doesn't destroy the habtm joins and still throws the exception
-    sicp = Lesson.new(:name => "SICP")
-    ben = Student.new(:name => "Ben Bitdiddle")
+    sicp = Lesson.new(name: "SICP")
+    ben = Student.new(name: "Ben Bitdiddle")
     sicp.students << ben
     sicp.save!
     assert_raises LessonError do
diff --git a/activerecord/test/cases/helper.rb b/activerecord/test/cases/helper.rb
index d2fdf03e9d..6ea02ac191 100644
--- a/activerecord/test/cases/helper.rb
+++ b/activerecord/test/cases/helper.rb
@@ -1,17 +1,16 @@
-require 'config'
+# frozen_string_literal: true
 
-require 'active_support/testing/autorun'
-require 'active_support/testing/method_call_assertions'
-require 'stringio'
+require "config"
 
-require 'active_record'
-require 'cases/test_case'
-require 'active_support/dependencies'
-require 'active_support/logger'
-require 'active_support/core_ext/string/strip'
+require "stringio"
 
-require 'support/config'
-require 'support/connection'
+require "active_record"
+require "cases/test_case"
+require "active_support/dependencies"
+require "active_support/logger"
+
+require "support/config"
+require "support/connection"
 
 # TODO: Move all these random hacks into the ARTest namespace and into the support/ dir
 
@@ -27,10 +26,7 @@ I18n.enforce_available_locales = false
 ARTest.connect
 
 # Quote "type" if it's a reserved word for the current connection.
-QUOTED_TYPE = ActiveRecord::Base.connection.quote_column_name('type')
-
-# FIXME: Remove this when the deprecation cycle on TZ aware types by default ends.
-ActiveRecord::Base.time_zone_aware_types << :time
+QUOTED_TYPE = ActiveRecord::Base.connection.quote_column_name("type")
 
 def current_adapter?(*types)
   types.any? do |type|
@@ -49,18 +45,18 @@ def subsecond_precision_supported?
 end
 
 def mysql_enforcing_gtid_consistency?
-  current_adapter?(:Mysql2Adapter) && 'ON' == ActiveRecord::Base.connection.show_variable('enforce_gtid_consistency')
+  current_adapter?(:Mysql2Adapter) && "ON" == ActiveRecord::Base.connection.show_variable("enforce_gtid_consistency")
 end
 
 def supports_savepoints?
   ActiveRecord::Base.connection.supports_savepoints?
 end
 
-def with_env_tz(new_tz = 'US/Eastern')
-  old_tz, ENV['TZ'] = ENV['TZ'], new_tz
+def with_env_tz(new_tz = "US/Eastern")
+  old_tz, ENV["TZ"] = ENV["TZ"], new_tz
   yield
 ensure
-  old_tz ? ENV['TZ'] = old_tz : ENV.delete('TZ')
+  old_tz ? ENV["TZ"] = old_tz : ENV.delete("TZ")
 end
 
 def with_timezone_config(cfg)
@@ -134,21 +130,6 @@ def disable_extension!(extension, connection)
   connection.reconnect!
 end
 
-require "cases/validations_repair_helper"
-class ActiveSupport::TestCase
-  include ActiveRecord::TestFixtures
-  include ActiveRecord::ValidationsRepairHelper
-  include ActiveSupport::Testing::MethodCallAssertions
-
-  self.fixture_path = FIXTURES_ROOT
-  self.use_instantiated_fixtures  = false
-  self.use_transactional_tests = true
-
-  def create_fixtures(*fixture_set_names, &block)
-    ActiveRecord::FixtureSet.create_fixtures(ActiveSupport::TestCase.fixture_path, fixture_set_names, fixture_class_names, &block)
-  end
-end
-
 def load_schema
   # silence verbose schema loading
   original_stdout = $stdout
@@ -162,6 +143,8 @@ def load_schema
   if File.exist?(adapter_specific_schema_file)
     load adapter_specific_schema_file
   end
+
+  ActiveRecord::FixtureSet.reset_cache
 ensure
   $stdout = original_stdout
 end
@@ -188,17 +171,17 @@ end
 module InTimeZone
   private
 
-  def in_time_zone(zone)
-    old_zone  = Time.zone
-    old_tz    = ActiveRecord::Base.time_zone_aware_attributes
-
-    Time.zone = zone ? ActiveSupport::TimeZone[zone] : nil
-    ActiveRecord::Base.time_zone_aware_attributes = !zone.nil?
-    yield
-  ensure
-    Time.zone = old_zone
-    ActiveRecord::Base.time_zone_aware_attributes = old_tz
-  end
+    def in_time_zone(zone)
+      old_zone  = Time.zone
+      old_tz    = ActiveRecord::Base.time_zone_aware_attributes
+
+      Time.zone = zone ? ActiveSupport::TimeZone[zone] : nil
+      ActiveRecord::Base.time_zone_aware_attributes = !zone.nil?
+      yield
+    ensure
+      Time.zone = old_zone
+      ActiveRecord::Base.time_zone_aware_attributes = old_tz
+    end
 end
 
-require 'mocha/setup' # FIXME: stop using mocha
+require "mocha/setup" # FIXME: stop using mocha
diff --git a/activerecord/test/cases/hot_compatibility_test.rb b/activerecord/test/cases/hot_compatibility_test.rb
index 9fc75b7377..e7778af55b 100644
--- a/activerecord/test/cases/hot_compatibility_test.rb
+++ b/activerecord/test/cases/hot_compatibility_test.rb
@@ -1,5 +1,7 @@
-require 'cases/helper'
-require 'support/connection_helper'
+# frozen_string_literal: true
+
+require "cases/helper"
+require "support/connection_helper"
 
 class HotCompatibilityTest < ActiveRecord::TestCase
   self.use_transactional_tests = false
@@ -12,7 +14,7 @@ class HotCompatibilityTest < ActiveRecord::TestCase
         t.string :bar
       end
 
-      def self.name; 'HotCompatibility'; end
+      def self.name; "HotCompatibility"; end
     end
   end
 
@@ -35,29 +37,29 @@ class HotCompatibilityTest < ActiveRecord::TestCase
 
     # but we can successfully create a record so long as we don't
     # reference the removed column
-    record = @klass.create! foo: 'foo'
+    record = @klass.create! foo: "foo"
     record.reload
-    assert_equal 'foo', record.foo
+    assert_equal "foo", record.foo
   end
 
   test "update after remove_column" do
-    record = @klass.create! foo: 'foo'
+    record = @klass.create! foo: "foo"
     assert_equal 3, @klass.columns.length
     @klass.connection.remove_column :hot_compatibilities, :bar
     assert_equal 3, @klass.columns.length
 
     record.reload
-    assert_equal 'foo', record.foo
-    record.foo = 'bar'
+    assert_equal "foo", record.foo
+    record.foo = "bar"
     record.save!
     record.reload
-    assert_equal 'bar', record.foo
+    assert_equal "bar", record.foo
   end
 
   if current_adapter?(:PostgreSQLAdapter)
     test "cleans up after prepared statement failure in a transaction" do
       with_two_connections do |original_connection, ddl_connection|
-        record = @klass.create! bar: 'bar'
+        record = @klass.create! bar: "bar"
 
         # prepare the reload statement in a transaction
         @klass.transaction do
@@ -83,7 +85,7 @@ class HotCompatibilityTest < ActiveRecord::TestCase
 
     test "cleans up after prepared statement failure in nested transactions" do
       with_two_connections do |original_connection, ddl_connection|
-        record = @klass.create! bar: 'bar'
+        record = @klass.create! bar: "bar"
 
         # prepare the reload statement in a transaction
         @klass.transaction do
@@ -114,29 +116,29 @@ class HotCompatibilityTest < ActiveRecord::TestCase
 
   private
 
-  def get_prepared_statement_cache(connection)
-    connection.instance_variable_get(:@statements)
-      .instance_variable_get(:@cache)[Process.pid]
-  end
+    def get_prepared_statement_cache(connection)
+      connection.instance_variable_get(:@statements)
+        .instance_variable_get(:@cache)[Process.pid]
+    end
 
-  # Rails will automatically clear the prepared statements on the connection
-  # that runs the migration, so we use two connections to simulate what would
-  # actually happen on a production system; we'd have one connection running the
-  # migration from the rake task ("ddl_connection" here), and we'd have another
-  # connection in a web worker.
-  def with_two_connections
-    run_without_connection do |original_connection|
-      ActiveRecord::Base.establish_connection(original_connection.merge(pool_size: 2))
-      begin
-        ddl_connection = ActiveRecord::Base.connection_pool.checkout
+    # Rails will automatically clear the prepared statements on the connection
+    # that runs the migration, so we use two connections to simulate what would
+    # actually happen on a production system; we'd have one connection running the
+    # migration from the rake task ("ddl_connection" here), and we'd have another
+    # connection in a web worker.
+    def with_two_connections
+      run_without_connection do |original_connection|
+        ActiveRecord::Base.establish_connection(original_connection.merge(pool_size: 2))
         begin
-          yield original_connection, ddl_connection
+          ddl_connection = ActiveRecord::Base.connection_pool.checkout
+          begin
+            yield original_connection, ddl_connection
+          ensure
+            ActiveRecord::Base.connection_pool.checkin ddl_connection
+          end
         ensure
-          ActiveRecord::Base.connection_pool.checkin ddl_connection
+          ActiveRecord::Base.clear_all_connections!
         end
-      ensure
-        ActiveRecord::Base.clear_all_connections!
       end
     end
-  end
 end
diff --git a/activerecord/test/cases/i18n_test.rb b/activerecord/test/cases/i18n_test.rb
index a428f1d87b..22981c142a 100644
--- a/activerecord/test/cases/i18n_test.rb
+++ b/activerecord/test/cases/i18n_test.rb
@@ -1,45 +1,46 @@
+# frozen_string_literal: true
+
 require "cases/helper"
-require 'models/topic'
-require 'models/reply'
+require "models/topic"
+require "models/reply"
 
 class ActiveRecordI18nTests < ActiveRecord::TestCase
-
   def setup
     I18n.backend = I18n::Backend::Simple.new
   end
 
   def test_translated_model_attributes
-    I18n.backend.store_translations 'en', :activerecord => {:attributes => {:topic => {:title => 'topic title attribute'} } }
-    assert_equal 'topic title attribute', Topic.human_attribute_name('title')
+    I18n.backend.store_translations "en", activerecord: { attributes: { topic: { title: "topic title attribute" } } }
+    assert_equal "topic title attribute", Topic.human_attribute_name("title")
   end
 
   def test_translated_model_attributes_with_symbols
-    I18n.backend.store_translations 'en', :activerecord => {:attributes => {:topic => {:title => 'topic title attribute'} } }
-    assert_equal 'topic title attribute', Topic.human_attribute_name(:title)
+    I18n.backend.store_translations "en", activerecord: { attributes: { topic: { title: "topic title attribute" } } }
+    assert_equal "topic title attribute", Topic.human_attribute_name(:title)
   end
 
   def test_translated_model_attributes_with_sti
-    I18n.backend.store_translations 'en', :activerecord => {:attributes => {:reply => {:title => 'reply title attribute'} } }
-    assert_equal 'reply title attribute', Reply.human_attribute_name('title')
+    I18n.backend.store_translations "en", activerecord: { attributes: { reply: { title: "reply title attribute" } } }
+    assert_equal "reply title attribute", Reply.human_attribute_name("title")
   end
 
   def test_translated_model_attributes_with_sti_fallback
-    I18n.backend.store_translations 'en', :activerecord => {:attributes => {:topic => {:title => 'topic title attribute'} } }
-    assert_equal 'topic title attribute', Reply.human_attribute_name('title')
+    I18n.backend.store_translations "en", activerecord: { attributes: { topic: { title: "topic title attribute" } } }
+    assert_equal "topic title attribute", Reply.human_attribute_name("title")
   end
 
   def test_translated_model_names
-    I18n.backend.store_translations 'en', :activerecord => {:models => {:topic => 'topic model'} }
-    assert_equal 'topic model', Topic.model_name.human
+    I18n.backend.store_translations "en", activerecord: { models: { topic: "topic model" } }
+    assert_equal "topic model", Topic.model_name.human
   end
 
   def test_translated_model_names_with_sti
-    I18n.backend.store_translations 'en', :activerecord => {:models => {:reply => 'reply model'} }
-    assert_equal 'reply model', Reply.model_name.human
+    I18n.backend.store_translations "en", activerecord: { models: { reply: "reply model" } }
+    assert_equal "reply model", Reply.model_name.human
   end
 
   def test_translated_model_names_with_sti_fallback
-    I18n.backend.store_translations 'en', :activerecord => {:models => {:topic => 'topic model'} }
-    assert_equal 'topic model', Reply.model_name.human
+    I18n.backend.store_translations "en", activerecord: { models: { topic: "topic model" } }
+    assert_equal "topic model", Reply.model_name.human
   end
 end
diff --git a/activerecord/test/cases/inheritance_test.rb b/activerecord/test/cases/inheritance_test.rb
index e234b9a6a9..ff4385c8b4 100644
--- a/activerecord/test/cases/inheritance_test.rb
+++ b/activerecord/test/cases/inheritance_test.rb
@@ -1,13 +1,16 @@
-require 'cases/helper'
-require 'models/author'
-require 'models/company'
-require 'models/person'
-require 'models/post'
-require 'models/project'
-require 'models/subscriber'
-require 'models/vegetables'
-require 'models/shop'
-require 'models/sponsor'
+# frozen_string_literal: true
+
+require "cases/helper"
+require "models/author"
+require "models/company"
+require "models/membership"
+require "models/person"
+require "models/post"
+require "models/project"
+require "models/subscriber"
+require "models/vegetables"
+require "models/shop"
+require "models/sponsor"
 
 module InheritanceTestHelper
   def with_store_full_sti_class(&block)
@@ -29,11 +32,11 @@ end
 
 class InheritanceTest < ActiveRecord::TestCase
   include InheritanceTestHelper
-  fixtures :companies, :projects, :subscribers, :accounts, :vegetables
+  fixtures :companies, :projects, :subscribers, :accounts, :vegetables, :memberships
 
   def test_class_with_store_full_sti_class_returns_full_name
     with_store_full_sti_class do
-      assert_equal 'Namespaced::Company', Namespaced::Company.sti_name
+      assert_equal "Namespaced::Company", Namespaced::Company.sti_name
     end
   end
 
@@ -42,37 +45,37 @@ class InheritanceTest < ActiveRecord::TestCase
     company = company.dup
     company.extend(Module.new {
       def _read_attribute(name)
-        return '  ' if name == 'type'
+        return "  " if name == "type"
         super
       end
     })
     company.save!
     company = Company.all.to_a.find { |x| x.id == company.id }
-    assert_equal '  ', company.type
+    assert_equal "  ", company.type
   end
 
   def test_class_without_store_full_sti_class_returns_demodulized_name
     without_store_full_sti_class do
-      assert_equal 'Company', Namespaced::Company.sti_name
+      assert_equal "Company", Namespaced::Company.sti_name
     end
   end
 
   def test_compute_type_success
-    assert_equal Author, ActiveRecord::Base.send(:compute_type, 'Author')
+    assert_equal Author, Company.send(:compute_type, "Author")
   end
 
   def test_compute_type_nonexistent_constant
     e = assert_raises NameError do
-      ActiveRecord::Base.send :compute_type, 'NonexistentModel'
+      Company.send :compute_type, "NonexistentModel"
     end
-    assert_equal 'uninitialized constant ActiveRecord::Base::NonexistentModel', e.message
-    assert_equal 'ActiveRecord::Base::NonexistentModel', e.name
+    assert_equal "uninitialized constant Company::NonexistentModel", e.message
+    assert_equal "Company::NonexistentModel", e.name
   end
 
   def test_compute_type_no_method_error
-    ActiveSupport::Dependencies.stub(:safe_constantize, proc{ raise NoMethodError }) do
+    ActiveSupport::Dependencies.stub(:safe_constantize, proc { raise NoMethodError }) do
       assert_raises NoMethodError do
-        ActiveRecord::Base.send :compute_type, 'InvalidModel'
+        Company.send :compute_type, "InvalidModel"
       end
     end
   end
@@ -87,19 +90,19 @@ class InheritanceTest < ActiveRecord::TestCase
       error = e
     end
 
-    ActiveSupport::Dependencies.stub(:safe_constantize, proc{ raise e }) do
+    ActiveSupport::Dependencies.stub(:safe_constantize, proc { raise e }) do
 
       exception = assert_raises NameError do
-        ActiveRecord::Base.send :compute_type, 'InvalidModel'
+        Company.send :compute_type, "InvalidModel"
       end
       assert_equal error.message, exception.message
     end
   end
 
   def test_compute_type_argument_error
-    ActiveSupport::Dependencies.stub(:safe_constantize, proc{ raise ArgumentError }) do
+    ActiveSupport::Dependencies.stub(:safe_constantize, proc { raise ArgumentError }) do
       assert_raises ArgumentError do
-        ActiveRecord::Base.send :compute_type, 'InvalidModel'
+        Company.send :compute_type, "InvalidModel"
       end
     end
   end
@@ -107,14 +110,14 @@ class InheritanceTest < ActiveRecord::TestCase
   def test_should_store_demodulized_class_name_with_store_full_sti_class_option_disabled
     without_store_full_sti_class do
       item = Namespaced::Company.new
-      assert_equal 'Company', item[:type]
+      assert_equal "Company", item[:type]
     end
   end
 
   def test_should_store_full_class_name_with_store_full_sti_class_option_enabled
     with_store_full_sti_class do
       item = Namespaced::Company.new
-      assert_equal 'Namespaced::Company', item[:type]
+      assert_equal "Namespaced::Company", item[:type]
     end
   end
 
@@ -144,19 +147,23 @@ class InheritanceTest < ActiveRecord::TestCase
     # Concrete subclass of AR::Base.
     assert Post.descends_from_active_record?
 
+    # Concrete subclasses of a concrete class which has a type column.
+    assert !StiPost.descends_from_active_record?
+    assert !SubStiPost.descends_from_active_record?
+
     # Abstract subclass of a concrete class which has a type column.
     # This is pathological, as you'll never have Sub < Abstract < Concrete.
-    assert !StiPost.descends_from_active_record?
+    assert !AbstractStiPost.descends_from_active_record?
 
-    # Concrete subclasses an abstract class which has a type column.
-    assert !SubStiPost.descends_from_active_record?
+    # Concrete subclass of an abstract class which has a type column.
+    assert !SubAbstractStiPost.descends_from_active_record?
   end
 
   def test_company_descends_from_active_record
     assert !ActiveRecord::Base.descends_from_active_record?
-    assert AbstractCompany.descends_from_active_record?, 'AbstractCompany should descend from ActiveRecord::Base'
-    assert Company.descends_from_active_record?, 'Company should descend from ActiveRecord::Base'
-    assert !Class.new(Company).descends_from_active_record?, 'Company subclass should not descend from ActiveRecord::Base'
+    assert AbstractCompany.descends_from_active_record?, "AbstractCompany should descend from ActiveRecord::Base"
+    assert Company.descends_from_active_record?, "Company should descend from ActiveRecord::Base"
+    assert !Class.new(Company).descends_from_active_record?, "Company subclass should not descend from ActiveRecord::Base"
   end
 
   def test_abstract_class
@@ -169,7 +176,8 @@ class InheritanceTest < ActiveRecord::TestCase
     assert_equal Post, Post.base_class
     assert_equal Post, SpecialPost.base_class
     assert_equal Post, StiPost.base_class
-    assert_equal SubStiPost, SubStiPost.base_class
+    assert_equal Post, SubStiPost.base_class
+    assert_equal SubAbstractStiPost, SubAbstractStiPost.base_class
   end
 
   def test_abstract_inheritance_base_class
@@ -214,7 +222,7 @@ class InheritanceTest < ActiveRecord::TestCase
   def test_becomes_and_change_tracking_for_inheritance_columns
     cucumber = Vegetable.find(1)
     cabbage = cucumber.becomes!(Cabbage)
-    assert_equal ['Cucumber', 'Cabbage'], cabbage.custom_type_change
+    assert_equal ["Cucumber", "Cabbage"], cabbage.custom_type_change
   end
 
   def test_alt_becomes_bang_resets_inheritance_type_column
@@ -229,13 +237,13 @@ class InheritanceTest < ActiveRecord::TestCase
   end
 
   def test_inheritance_find_all
-    companies = Company.all.merge!(:order => 'id').to_a
+    companies = Company.all.merge!(order: "id").to_a
     assert_kind_of Firm, companies[0], "37signals should be a firm"
     assert_kind_of Client, companies[1], "Summit should be a client"
   end
 
   def test_alt_inheritance_find_all
-    companies = Vegetable.all.merge!(:order => 'id').to_a
+    companies = Vegetable.all.merge!(order: "id").to_a
     assert_kind_of Cucumber, companies[0]
     assert_kind_of Cabbage, companies[1]
   end
@@ -250,7 +258,7 @@ class InheritanceTest < ActiveRecord::TestCase
   end
 
   def test_alt_inheritance_save
-    cabbage = Cabbage.new(:name => 'Savoy')
+    cabbage = Cabbage.new(name: "Savoy")
     cabbage.save!
 
     savoy = Vegetable.find(cabbage.id)
@@ -263,12 +271,27 @@ class InheritanceTest < ActiveRecord::TestCase
   end
 
   def test_inheritance_new_with_base_class
-    company = Company.new(:type => 'Company')
+    company = Company.new(type: "Company")
     assert_equal Company, company.class
   end
 
   def test_inheritance_new_with_subclass
-    firm = Company.new(:type => 'Firm')
+    firm = Company.new(type: "Firm")
+    assert_equal Firm, firm.class
+  end
+
+  def test_where_new_with_subclass
+    firm = Company.where(type: "Firm").new
+    assert_equal Firm, firm.class
+  end
+
+  def test_where_create_with_subclass
+    firm = Company.where(type: "Firm").create(name: "Basecamp")
+    assert_equal Firm, firm.class
+  end
+
+  def test_where_create_bang_with_subclass
+    firm = Company.where(type: "Firm").create!(name: "Basecamp")
     assert_equal Firm, firm.class
   end
 
@@ -287,17 +310,41 @@ class InheritanceTest < ActiveRecord::TestCase
   end
 
   def test_new_with_invalid_type
-    assert_raise(ActiveRecord::SubclassNotFound) { Company.new(:type => 'InvalidType') }
+    assert_raise(ActiveRecord::SubclassNotFound) { Company.new(type: "InvalidType") }
   end
 
   def test_new_with_unrelated_type
-    assert_raise(ActiveRecord::SubclassNotFound) { Company.new(:type => 'Account') }
+    assert_raise(ActiveRecord::SubclassNotFound) { Company.new(type: "Account") }
+  end
+
+  def test_where_new_with_invalid_type
+    assert_raise(ActiveRecord::SubclassNotFound) { Company.where(type: "InvalidType").new }
+  end
+
+  def test_where_new_with_unrelated_type
+    assert_raise(ActiveRecord::SubclassNotFound) { Company.where(type: "Account").new }
+  end
+
+  def test_where_create_with_invalid_type
+    assert_raise(ActiveRecord::SubclassNotFound) { Company.where(type: "InvalidType").create }
+  end
+
+  def test_where_create_with_unrelated_type
+    assert_raise(ActiveRecord::SubclassNotFound) { Company.where(type: "Account").create }
+  end
+
+  def test_where_create_bang_with_invalid_type
+    assert_raise(ActiveRecord::SubclassNotFound) { Company.where(type: "InvalidType").create! }
+  end
+
+  def test_where_create_bang_with_unrelated_type
+    assert_raise(ActiveRecord::SubclassNotFound) { Company.where(type: "Account").create! }
   end
 
   def test_new_with_unrelated_namespaced_type
     without_store_full_sti_class do
       e = assert_raises ActiveRecord::SubclassNotFound do
-        Namespaced::Company.new(type: 'Firm')
+        Namespaced::Company.new(type: "Firm")
       end
 
       assert_equal "Invalid single-table inheritance type: Namespaced::Firm is not a subclass of Namespaced::Company", e.message
@@ -305,21 +352,21 @@ class InheritanceTest < ActiveRecord::TestCase
   end
 
   def test_new_with_complex_inheritance
-    assert_nothing_raised { Client.new(type: 'VerySpecialClient') }
+    assert_nothing_raised { Client.new(type: "VerySpecialClient") }
   end
 
   def test_new_without_storing_full_sti_class
     without_store_full_sti_class do
-      item = Company.new(type: 'SpecialCo')
+      item = Company.new(type: "SpecialCo")
       assert_instance_of Company::SpecialCo, item
     end
   end
 
   def test_new_with_autoload_paths
-    path = File.expand_path('../../models/autoloadable', __FILE__)
+    path = File.expand_path("../models/autoloadable", __dir__)
     ActiveSupport::Dependencies.autoload_paths << path
 
-    firm = Company.new(:type => 'ExtraFirm')
+    firm = Company.new(type: "ExtraFirm")
     assert_equal ExtraFirm, firm.class
   ensure
     ActiveSupport::Dependencies.autoload_paths.reject! { |p| p == path }
@@ -352,7 +399,7 @@ class InheritanceTest < ActiveRecord::TestCase
     Client.update_all "name = 'I am a client'"
     assert_equal "I am a client", Client.first.name
     # Order by added as otherwise Oracle tests were failing because of different order of results
-    assert_equal "37signals", Firm.all.merge!(:order => "id").to_a.first.name
+    assert_equal "37signals", Firm.all.merge!(order: "id").to_a.first.name
   end
 
   def test_alt_update_all_within_inheritance
@@ -374,51 +421,52 @@ class InheritanceTest < ActiveRecord::TestCase
   end
 
   def test_find_first_within_inheritance
-    assert_kind_of Firm, Company.all.merge!(:where => "name = '37signals'").first
-    assert_kind_of Firm, Firm.all.merge!(:where => "name = '37signals'").first
-    assert_nil Client.all.merge!(:where => "name = '37signals'").first
+    assert_kind_of Firm, Company.all.merge!(where: "name = '37signals'").first
+    assert_kind_of Firm, Firm.all.merge!(where: "name = '37signals'").first
+    assert_nil Client.all.merge!(where: "name = '37signals'").first
   end
 
   def test_alt_find_first_within_inheritance
-    assert_kind_of Cabbage, Vegetable.all.merge!(:where => "name = 'his cabbage'").first
-    assert_kind_of Cabbage, Cabbage.all.merge!(:where => "name = 'his cabbage'").first
-    assert_nil Cucumber.all.merge!(:where => "name = 'his cabbage'").first
+    assert_kind_of Cabbage, Vegetable.all.merge!(where: "name = 'his cabbage'").first
+    assert_kind_of Cabbage, Cabbage.all.merge!(where: "name = 'his cabbage'").first
+    assert_nil Cucumber.all.merge!(where: "name = 'his cabbage'").first
   end
 
   def test_complex_inheritance
     very_special_client = VerySpecialClient.create("name" => "veryspecial")
     assert_equal very_special_client, VerySpecialClient.where("name = 'veryspecial'").first
-    assert_equal very_special_client, SpecialClient.all.merge!(:where => "name = 'veryspecial'").first
-    assert_equal very_special_client, Company.all.merge!(:where => "name = 'veryspecial'").first
-    assert_equal very_special_client, Client.all.merge!(:where => "name = 'veryspecial'").first
-    assert_equal 1, Client.all.merge!(:where => "name = 'Summit'").to_a.size
+    assert_equal very_special_client, SpecialClient.all.merge!(where: "name = 'veryspecial'").first
+    assert_equal very_special_client, Company.all.merge!(where: "name = 'veryspecial'").first
+    assert_equal very_special_client, Client.all.merge!(where: "name = 'veryspecial'").first
+    assert_equal 1, Client.all.merge!(where: "name = 'Summit'").to_a.size
     assert_equal very_special_client, Client.find(very_special_client.id)
   end
 
   def test_alt_complex_inheritance
     king_cole = KingCole.create("name" => "uniform heads")
     assert_equal king_cole, KingCole.where("name = 'uniform heads'").first
-    assert_equal king_cole, GreenCabbage.all.merge!(:where => "name = 'uniform heads'").first
-    assert_equal king_cole, Cabbage.all.merge!(:where => "name = 'uniform heads'").first
-    assert_equal king_cole, Vegetable.all.merge!(:where => "name = 'uniform heads'").first
-    assert_equal 1, Cabbage.all.merge!(:where => "name = 'his cabbage'").to_a.size
+    assert_equal king_cole, GreenCabbage.all.merge!(where: "name = 'uniform heads'").first
+    assert_equal king_cole, Cabbage.all.merge!(where: "name = 'uniform heads'").first
+    assert_equal king_cole, Vegetable.all.merge!(where: "name = 'uniform heads'").first
+    assert_equal 1, Cabbage.all.merge!(where: "name = 'his cabbage'").to_a.size
     assert_equal king_cole, Cabbage.find(king_cole.id)
   end
 
   def test_eager_load_belongs_to_something_inherited
-    account = Account.all.merge!(:includes => :firm).find(1)
+    account = Account.all.merge!(includes: :firm).find(1)
     assert account.association(:firm).loaded?, "association was not eager loaded"
   end
 
   def test_alt_eager_loading
-    cabbage = RedCabbage.all.merge!(:includes => :seller).find(4)
+    cabbage = RedCabbage.all.merge!(includes: :seller).find(4)
     assert cabbage.association(:seller).loaded?, "association was not eager loaded"
   end
 
   def test_eager_load_belongs_to_primary_key_quoting
     con = Account.connection
-    assert_sql(/#{con.quote_table_name('companies')}.#{con.quote_column_name('id')} = 1/) do
-      Account.all.merge!(:includes => :firm).find(1)
+    bind_param = Arel::Nodes::BindParam.new(nil)
+    assert_sql(/#{con.quote_table_name('companies')}\.#{con.quote_column_name('id')} = (?:#{Regexp.quote(bind_param.to_sql)}|1)/) do
+      Account.all.merge!(includes: :firm).find(1)
     end
   end
 
@@ -428,13 +476,17 @@ class InheritanceTest < ActiveRecord::TestCase
 
   def test_inheritance_without_mapping
     assert_kind_of SpecialSubscriber, SpecialSubscriber.find("webster132")
-    assert_nothing_raised { s = SpecialSubscriber.new("name" => "And breaaaaathe!"); s.id = 'roger'; s.save }
+    assert_nothing_raised { s = SpecialSubscriber.new("name" => "And breaaaaathe!"); s.id = "roger"; s.save }
   end
 
   def test_scope_inherited_properly
     assert_nothing_raised { Company.of_first_firm }
     assert_nothing_raised { Client.of_first_firm }
   end
+
+  def test_inheritance_with_default_scope
+    assert_equal 1, SelectedMembership.count(:all)
+  end
 end
 
 class InheritanceComputeTypeTest < ActiveRecord::TestCase
@@ -449,7 +501,7 @@ class InheritanceComputeTypeTest < ActiveRecord::TestCase
   def test_instantiation_doesnt_try_to_require_corresponding_file
     without_store_full_sti_class do
       foo = Firm.first.clone
-      foo.type = 'FirmOnTheFly'
+      foo.type = "FirmOnTheFly"
       foo.save!
 
       # Should fail without FirmOnTheFly in the type condition.
@@ -470,30 +522,30 @@ class InheritanceComputeTypeTest < ActiveRecord::TestCase
   end
 
   def test_sti_type_from_attributes_disabled_in_non_sti_class
-    phone = Shop::Product::Type.new(name: 'Phone')
-    product = Shop::Product.new(:type => phone)
+    phone = Shop::Product::Type.new(name: "Phone")
+    product = Shop::Product.new(type: phone)
     assert product.save
   end
 
   def test_inheritance_new_with_subclass_as_default
     original_type = Company.columns_hash["type"].default
-    ActiveRecord::Base.connection.change_column_default :companies, :type, 'Firm'
+    ActiveRecord::Base.connection.change_column_default :companies, :type, "Firm"
     Company.reset_column_information
 
     firm = Company.new # without arguments
-    assert_equal 'Firm', firm.type
+    assert_equal "Firm", firm.type
     assert_instance_of Firm, firm
 
-    firm = Company.new(firm_name: 'Shri Hans Plastic') # with arguments
-    assert_equal 'Firm', firm.type
+    firm = Company.new(firm_name: "Shri Hans Plastic") # with arguments
+    assert_equal "Firm", firm.type
     assert_instance_of Firm, firm
 
     client = Client.new
-    assert_equal 'Client', client.type
+    assert_equal "Client", client.type
     assert_instance_of Client, client
 
-    firm = Company.new(type: 'Client') # overwrite the default type
-    assert_equal 'Client', firm.type
+    firm = Company.new(type: "Client") # overwrite the default type
+    assert_equal "Client", firm.type
     assert_instance_of Client, firm
   ensure
     ActiveRecord::Base.connection.change_column_default :companies, :type, original_type
@@ -502,9 +554,8 @@ class InheritanceComputeTypeTest < ActiveRecord::TestCase
 end
 
 class InheritanceAttributeTest < ActiveRecord::TestCase
-
   class Company < ActiveRecord::Base
-    self.table_name = 'companies'
+    self.table_name = "companies"
     attribute :type, :string, default: "InheritanceAttributeTest::Startup"
   end
 
@@ -516,11 +567,11 @@ class InheritanceAttributeTest < ActiveRecord::TestCase
 
   def test_inheritance_new_with_subclass_as_default
     startup = Company.new # without arguments
-    assert_equal 'InheritanceAttributeTest::Startup', startup.type
+    assert_equal "InheritanceAttributeTest::Startup", startup.type
     assert_instance_of Startup, startup
 
-    empire = Company.new(type: 'InheritanceAttributeTest::Empire') # without arguments
-    assert_equal 'InheritanceAttributeTest::Empire', empire.type
+    empire = Company.new(type: "InheritanceAttributeTest::Empire") # without arguments
+    assert_equal "InheritanceAttributeTest::Empire", empire.type
     assert_instance_of Empire, empire
   end
 end
@@ -555,7 +606,7 @@ class InheritanceAttributeMappingTest < ActiveRecord::TestCase
   end
 
   class Company < ActiveRecord::Base
-    self.table_name = 'companies'
+    self.table_name = "companies"
     attribute :type, :omg_sti
   end
 
@@ -563,18 +614,18 @@ class InheritanceAttributeMappingTest < ActiveRecord::TestCase
   class Empire < Company; end
 
   class Sponsor < ActiveRecord::Base
-    self.table_name = 'sponsors'
+    self.table_name = "sponsors"
     attribute :sponsorable_type, :omg_sti
 
     belongs_to :sponsorable, polymorphic: true
   end
 
   def test_sti_with_custom_type
-    Startup.create! name: 'a Startup'
-    Empire.create! name: 'an Empire'
+    Startup.create! name: "a Startup"
+    Empire.create! name: "an Empire"
 
     assert_equal [["a Startup", "omg_inheritance_attribute_mapping_test/startup"],
-                  ["an Empire", "omg_inheritance_attribute_mapping_test/empire"]], ActiveRecord::Base.connection.select_rows('SELECT name, type FROM companies').sort
+                  ["an Empire", "omg_inheritance_attribute_mapping_test/empire"]], ActiveRecord::Base.connection.select_rows("SELECT name, type FROM companies").sort
     assert_equal [["a Startup", "InheritanceAttributeMappingTest::Startup"],
                   ["an Empire", "InheritanceAttributeMappingTest::Empire"]], Company.all.map { |a| [a.name, a.type] }.sort
 
@@ -583,17 +634,17 @@ class InheritanceAttributeMappingTest < ActiveRecord::TestCase
     startup.save!
 
     assert_equal [["a Startup", "omg_inheritance_attribute_mapping_test/empire"],
-                  ["an Empire", "omg_inheritance_attribute_mapping_test/empire"]], ActiveRecord::Base.connection.select_rows('SELECT name, type FROM companies').sort
+                  ["an Empire", "omg_inheritance_attribute_mapping_test/empire"]], ActiveRecord::Base.connection.select_rows("SELECT name, type FROM companies").sort
 
     assert_equal [["a Startup", "InheritanceAttributeMappingTest::Empire"],
                   ["an Empire", "InheritanceAttributeMappingTest::Empire"]], Company.all.map { |a| [a.name, a.type] }.sort
   end
 
   def test_polymorphic_associations_custom_type
-    startup = Startup.create! name: 'a Startup'
+    startup = Startup.create! name: "a Startup"
     sponsor = Sponsor.create! sponsorable: startup
 
-    assert_equal ["omg_inheritance_attribute_mapping_test/company"], ActiveRecord::Base.connection.select_values('SELECT sponsorable_type FROM sponsors')
+    assert_equal ["omg_inheritance_attribute_mapping_test/company"], ActiveRecord::Base.connection.select_values("SELECT sponsorable_type FROM sponsors")
 
     sponsor = Sponsor.first
     assert_equal startup, sponsor.sponsorable
diff --git a/activerecord/test/cases/instrumentation_test.rb b/activerecord/test/cases/instrumentation_test.rb
new file mode 100644
index 0000000000..e6e8468757
--- /dev/null
+++ b/activerecord/test/cases/instrumentation_test.rb
@@ -0,0 +1,72 @@
+# frozen_string_literal: true
+
+require "cases/helper"
+require "models/book"
+
+module ActiveRecord
+  class InstrumentationTest < ActiveRecord::TestCase
+    def test_payload_name_on_load
+      Book.create(name: "test book")
+      subscriber = ActiveSupport::Notifications.subscribe("sql.active_record") do |*args|
+        event = ActiveSupport::Notifications::Event.new(*args)
+        if event.payload[:sql].match "SELECT"
+          assert_equal "Book Load", event.payload[:name]
+        end
+      end
+      Book.first
+    ensure
+      ActiveSupport::Notifications.unsubscribe(subscriber) if subscriber
+    end
+
+    def test_payload_name_on_create
+      subscriber = ActiveSupport::Notifications.subscribe("sql.active_record") do |*args|
+        event = ActiveSupport::Notifications::Event.new(*args)
+        if event.payload[:sql].match "INSERT"
+          assert_equal "Book Create", event.payload[:name]
+        end
+      end
+      Book.create(name: "test book")
+    ensure
+      ActiveSupport::Notifications.unsubscribe(subscriber) if subscriber
+    end
+
+    def test_payload_name_on_update
+      subscriber = ActiveSupport::Notifications.subscribe("sql.active_record") do |*args|
+        event = ActiveSupport::Notifications::Event.new(*args)
+        if event.payload[:sql].match "UPDATE"
+          assert_equal "Book Update", event.payload[:name]
+        end
+      end
+      book = Book.create(name: "test book")
+      book.update_attribute(:name, "new name")
+    ensure
+      ActiveSupport::Notifications.unsubscribe(subscriber) if subscriber
+    end
+
+    def test_payload_name_on_update_all
+      subscriber = ActiveSupport::Notifications.subscribe("sql.active_record") do |*args|
+        event = ActiveSupport::Notifications::Event.new(*args)
+        if event.payload[:sql].match "UPDATE"
+          assert_equal "Book Update All", event.payload[:name]
+        end
+      end
+      Book.create(name: "test book")
+      Book.update_all(name: "new name")
+    ensure
+      ActiveSupport::Notifications.unsubscribe(subscriber) if subscriber
+    end
+
+    def test_payload_name_on_destroy
+      subscriber = ActiveSupport::Notifications.subscribe("sql.active_record") do |*args|
+        event = ActiveSupport::Notifications::Event.new(*args)
+        if event.payload[:sql].match "DELETE"
+          assert_equal "Book Destroy", event.payload[:name]
+        end
+      end
+      book = Book.create(name: "test book")
+      book.destroy
+    ensure
+      ActiveSupport::Notifications.unsubscribe(subscriber) if subscriber
+    end
+  end
+end
diff --git a/activerecord/test/cases/integration_test.rb b/activerecord/test/cases/integration_test.rb
index 08a186ae07..36cd63c4d4 100644
--- a/activerecord/test/cases/integration_test.rb
+++ b/activerecord/test/cases/integration_test.rb
@@ -1,10 +1,11 @@
+# frozen_string_literal: true
 
-require 'cases/helper'
-require 'models/company'
-require 'models/developer'
-require 'models/computer'
-require 'models/owner'
-require 'models/pet'
+require "cases/helper"
+require "models/company"
+require "models/developer"
+require "models/computer"
+require "models/owner"
+require "models/pet"
 
 class IntegrationTest < ActiveRecord::TestCase
   fixtures :companies, :developers, :owners, :pets
@@ -15,59 +16,85 @@ class IntegrationTest < ActiveRecord::TestCase
 
   def test_to_param_returns_nil_if_not_persisted
     client = Client.new
-    assert_equal nil, client.to_param
+    assert_nil client.to_param
   end
 
   def test_to_param_returns_id_if_not_persisted_but_id_is_set
     client = Client.new
     client.id = 1
-    assert_equal '1', client.to_param
+    assert_equal "1", client.to_param
   end
 
   def test_to_param_class_method
     firm = Firm.find(4)
-    assert_equal '4-flamboyant-software', firm.to_param
+    assert_equal "4-flamboyant-software", firm.to_param
+  end
+
+  def test_to_param_class_method_truncates_words_properly
+    firm = Firm.find(4)
+    firm.name << ", Inc."
+    assert_equal "4-flamboyant-software", firm.to_param
+  end
+
+  def test_to_param_class_method_truncates_after_parameterize
+    firm = Firm.find(4)
+    firm.name = "Huey, Dewey, & Louie LLC"
+    #               123456789T123456789v
+    assert_equal "4-huey-dewey-louie-llc", firm.to_param
+  end
+
+  def test_to_param_class_method_truncates_after_parameterize_with_hyphens
+    firm = Firm.find(4)
+    firm.name = "Door-to-Door Wash-n-Fold Service"
+    #               123456789T123456789v
+    assert_equal "4-door-to-door-wash-n", firm.to_param
   end
 
   def test_to_param_class_method_truncates
     firm = Firm.find(4)
-    firm.name = 'a ' * 100
-    assert_equal '4-a-a-a-a-a-a-a-a-a', firm.to_param
+    firm.name = "a " * 100
+    assert_equal "4-a-a-a-a-a-a-a-a-a-a", firm.to_param
   end
 
   def test_to_param_class_method_truncates_edge_case
     firm = Firm.find(4)
-    firm.name = 'David HeinemeierHansson'
-    assert_equal '4-david', firm.to_param
+    firm.name = "David HeinemeierHansson"
+    assert_equal "4-david", firm.to_param
+  end
+
+  def test_to_param_class_method_truncates_case_shown_in_doc
+    firm = Firm.find(4)
+    firm.name = "David Heinemeier Hansson"
+    assert_equal "4-david-heinemeier", firm.to_param
   end
 
   def test_to_param_class_method_squishes
     firm = Firm.find(4)
     firm.name = "ab \n" * 100
-    assert_equal '4-ab-ab-ab-ab-ab-ab', firm.to_param
+    assert_equal "4-ab-ab-ab-ab-ab-ab-ab", firm.to_param
   end
 
   def test_to_param_class_method_multibyte_character
     firm = Firm.find(4)
     firm.name = "戦場ヶ原 ひたぎ"
-    assert_equal '4', firm.to_param
+    assert_equal "4", firm.to_param
   end
 
   def test_to_param_class_method_uses_default_if_blank
     firm = Firm.find(4)
     firm.name = nil
-    assert_equal '4', firm.to_param
-    firm.name = ' '
-    assert_equal '4', firm.to_param
+    assert_equal "4", firm.to_param
+    firm.name = " "
+    assert_equal "4", firm.to_param
   end
 
   def test_to_param_class_method_uses_default_if_not_persisted
-    firm = Firm.new(name: 'Fancy Shirts')
-    assert_equal nil, firm.to_param
+    firm = Firm.new(name: "Fancy Shirts")
+    assert_nil firm.to_param
   end
 
   def test_to_param_with_no_arguments
-    assert_equal 'Firm', Firm.to_param
+    assert_equal "Firm", Firm.to_param
   end
 
   def test_cache_key_for_existing_record_is_not_timezone_dependent
@@ -143,7 +170,65 @@ class IntegrationTest < ActiveRecord::TestCase
   end
 
   def test_named_timestamps_for_cache_key
-    owner = owners(:blackbeard)
-    assert_equal "owners/#{owner.id}-#{owner.happy_at.utc.to_s(:usec)}", owner.cache_key(:updated_at, :happy_at)
+    assert_deprecated do
+      owner = owners(:blackbeard)
+      assert_equal "owners/#{owner.id}-#{owner.happy_at.utc.to_s(:usec)}", owner.cache_key(:updated_at, :happy_at)
+    end
+  end
+
+  def test_cache_key_when_named_timestamp_is_nil
+    assert_deprecated do
+      owner = owners(:blackbeard)
+      owner.happy_at = nil
+      assert_equal "owners/#{owner.id}", owner.cache_key(:happy_at)
+    end
+  end
+
+  def test_cache_key_is_stable_with_versioning_on
+    Developer.cache_versioning = true
+
+    developer = Developer.first
+    first_key = developer.cache_key
+
+    developer.touch
+    second_key = developer.cache_key
+
+    assert_equal first_key, second_key
+  ensure
+    Developer.cache_versioning = false
+  end
+
+  def test_cache_version_changes_with_versioning_on
+    Developer.cache_versioning = true
+
+    developer     = Developer.first
+    first_version = developer.cache_version
+
+    travel 10.seconds do
+      developer.touch
+    end
+
+    second_version = developer.cache_version
+
+    assert_not_equal first_version, second_version
+  ensure
+    Developer.cache_versioning = false
+  end
+
+  def test_cache_key_retains_version_when_custom_timestamp_is_used
+    Developer.cache_versioning = true
+
+    developer = Developer.first
+    first_key = developer.cache_key_with_version
+
+    travel 10.seconds do
+      developer.touch
+    end
+
+    second_key = developer.cache_key_with_version
+
+    assert_not_equal first_key, second_key
+  ensure
+    Developer.cache_versioning = false
   end
 end
diff --git a/activerecord/test/cases/invalid_connection_test.rb b/activerecord/test/cases/invalid_connection_test.rb
index a16b52751a..a1be9c2780 100644
--- a/activerecord/test/cases/invalid_connection_test.rb
+++ b/activerecord/test/cases/invalid_connection_test.rb
@@ -1,24 +1,26 @@
+# frozen_string_literal: true
+
 require "cases/helper"
 
 if current_adapter?(:Mysql2Adapter)
-class TestAdapterWithInvalidConnection < ActiveRecord::TestCase
-  self.use_transactional_tests = false
+  class TestAdapterWithInvalidConnection < ActiveRecord::TestCase
+    self.use_transactional_tests = false
 
-  class Bird < ActiveRecord::Base
-  end
+    class Bird < ActiveRecord::Base
+    end
 
-  def setup
-    # Can't just use current adapter; sqlite3 will create a database
-    # file on the fly.
-    Bird.establish_connection adapter: 'mysql2', database: 'i_do_not_exist'
-  end
+    def setup
+      # Can't just use current adapter; sqlite3 will create a database
+      # file on the fly.
+      Bird.establish_connection adapter: "mysql2", database: "i_do_not_exist"
+    end
 
-  teardown do
-    Bird.remove_connection
-  end
+    teardown do
+      Bird.remove_connection
+    end
 
-  test "inspect on Model class does not raise" do
-    assert_equal "#{Bird.name} (call '#{Bird.name}.connection' to establish a connection)", Bird.inspect
+    test "inspect on Model class does not raise" do
+      assert_equal "#{Bird.name} (call '#{Bird.name}.connection' to establish a connection)", Bird.inspect
+    end
   end
 end
-end
diff --git a/activerecord/test/cases/invertible_migration_test.rb b/activerecord/test/cases/invertible_migration_test.rb
index aba854820b..ebe0b0aa87 100644
--- a/activerecord/test/cases/invertible_migration_test.rb
+++ b/activerecord/test/cases/invertible_migration_test.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require "cases/helper"
 
 class Horse < ActiveRecord::Base
@@ -6,7 +8,7 @@ end
 module ActiveRecord
   class InvertibleMigrationTest < ActiveRecord::TestCase
     class SilentMigration < ActiveRecord::Migration::Current
-      def write(text = '')
+      def write(text = "")
         # sssshhhhh!!
       end
     end
@@ -159,16 +161,23 @@ module ActiveRecord
       end
     end
 
+    class UpOnlyMigration < SilentMigration
+      def change
+        add_column :horses, :oldie, :integer, default: 0
+        up_only { execute "update horses set oldie = 1" }
+      end
+    end
+
+    self.use_transactional_tests = false
+
     setup do
       @verbose_was, ActiveRecord::Migration.verbose = ActiveRecord::Migration.verbose, false
     end
 
     teardown do
       %w[horses new_horses].each do |table|
-        ActiveSupport::Deprecation.silence do
-          if ActiveRecord::Base.connection.table_exists?(table)
-            ActiveRecord::Base.connection.drop_table(table)
-          end
+        if ActiveRecord::Base.connection.table_exists?(table)
+          ActiveRecord::Base.connection.drop_table(table)
         end
       end
       ActiveRecord::Migration.verbose = @verbose_was
@@ -199,14 +208,14 @@ module ActiveRecord
     def test_migrate_up
       migration = InvertibleMigration.new
       migration.migrate(:up)
-      ActiveSupport::Deprecation.silence { assert migration.connection.table_exists?("horses"), "horses should exist" }
+      assert migration.connection.table_exists?("horses"), "horses should exist"
     end
 
     def test_migrate_down
       migration = InvertibleMigration.new
       migration.migrate :up
       migration.migrate :down
-      ActiveSupport::Deprecation.silence { assert !migration.connection.table_exists?("horses") }
+      assert !migration.connection.table_exists?("horses")
     end
 
     def test_migrate_revert
@@ -214,36 +223,30 @@ module ActiveRecord
       revert = InvertibleRevertMigration.new
       migration.migrate :up
       revert.migrate :up
-      ActiveSupport::Deprecation.silence { assert !migration.connection.table_exists?("horses") }
+      assert !migration.connection.table_exists?("horses")
       revert.migrate :down
-      ActiveSupport::Deprecation.silence { assert migration.connection.table_exists?("horses") }
+      assert migration.connection.table_exists?("horses")
       migration.migrate :down
-      ActiveSupport::Deprecation.silence { assert !migration.connection.table_exists?("horses") }
+      assert !migration.connection.table_exists?("horses")
     end
 
     def test_migrate_revert_by_part
       InvertibleMigration.new.migrate :up
       received = []
       migration = InvertibleByPartsMigration.new
-      migration.test = ->(dir){
-        ActiveSupport::Deprecation.silence do
-          assert migration.connection.table_exists?("horses")
-          assert migration.connection.table_exists?("new_horses")
-        end
+      migration.test = ->(dir) {
+        assert migration.connection.table_exists?("horses")
+        assert migration.connection.table_exists?("new_horses")
         received << dir
       }
       migration.migrate :up
       assert_equal [:both, :up], received
-      ActiveSupport::Deprecation.silence do
-        assert !migration.connection.table_exists?("horses")
-        assert migration.connection.table_exists?("new_horses")
-      end
+      assert !migration.connection.table_exists?("horses")
+      assert migration.connection.table_exists?("new_horses")
       migration.migrate :down
       assert_equal [:both, :up, :both, :down], received
-      ActiveSupport::Deprecation.silence do
-        assert migration.connection.table_exists?("horses")
-        assert !migration.connection.table_exists?("new_horses")
-      end
+      assert migration.connection.table_exists?("horses")
+      assert !migration.connection.table_exists?("new_horses")
     end
 
     def test_migrate_revert_whole_migration
@@ -252,20 +255,20 @@ module ActiveRecord
         revert = RevertWholeMigration.new(klass)
         migration.migrate :up
         revert.migrate :up
-        ActiveSupport::Deprecation.silence { assert !migration.connection.table_exists?("horses") }
+        assert !migration.connection.table_exists?("horses")
         revert.migrate :down
-        ActiveSupport::Deprecation.silence { assert migration.connection.table_exists?("horses") }
+        assert migration.connection.table_exists?("horses")
         migration.migrate :down
-        ActiveSupport::Deprecation.silence { assert !migration.connection.table_exists?("horses") }
+        assert !migration.connection.table_exists?("horses")
       end
     end
 
     def test_migrate_nested_revert_whole_migration
       revert = NestedRevertWholeMigration.new(InvertibleRevertMigration)
       revert.migrate :down
-      ActiveSupport::Deprecation.silence { assert revert.connection.table_exists?("horses") }
+      assert revert.connection.table_exists?("horses")
       revert.migrate :up
-      ActiveSupport::Deprecation.silence { assert !revert.connection.table_exists?("horses") }
+      assert !revert.connection.table_exists?("horses")
     end
 
     def test_migrate_revert_change_column_default
@@ -291,21 +294,23 @@ module ActiveRecord
 
         migration1.migrate(:up)
         migration2.migrate(:up)
-        assert_equal true, Horse.connection.extension_enabled?('hstore')
+        assert_equal true, Horse.connection.extension_enabled?("hstore")
 
         migration3.migrate(:up)
-        assert_equal false, Horse.connection.extension_enabled?('hstore')
+        assert_equal false, Horse.connection.extension_enabled?("hstore")
 
         migration3.migrate(:down)
-        assert_equal true, Horse.connection.extension_enabled?('hstore')
+        assert_equal true, Horse.connection.extension_enabled?("hstore")
 
         migration2.migrate(:down)
-        assert_equal false, Horse.connection.extension_enabled?('hstore')
+        assert_equal false, Horse.connection.extension_enabled?("hstore")
+      ensure
+        enable_extension!("hstore", ActiveRecord::Base.connection)
       end
     end
 
     def test_revert_order
-      block = Proc.new{|t| t.string :name }
+      block = Proc.new { |t| t.string :name }
       recorder = ActiveRecord::Migration::CommandRecorder.new(ActiveRecord::Base.connection)
       recorder.instance_eval do
         create_table("apples", &block)
@@ -330,35 +335,35 @@ module ActiveRecord
 
     def test_legacy_up
       LegacyMigration.migrate :up
-      ActiveSupport::Deprecation.silence { assert ActiveRecord::Base.connection.table_exists?("horses"), "horses should exist" }
+      assert ActiveRecord::Base.connection.table_exists?("horses"), "horses should exist"
     end
 
     def test_legacy_down
       LegacyMigration.migrate :up
       LegacyMigration.migrate :down
-      ActiveSupport::Deprecation.silence { assert !ActiveRecord::Base.connection.table_exists?("horses"), "horses should not exist" }
+      assert !ActiveRecord::Base.connection.table_exists?("horses"), "horses should not exist"
     end
 
     def test_up
       LegacyMigration.up
-      ActiveSupport::Deprecation.silence { assert ActiveRecord::Base.connection.table_exists?("horses"), "horses should exist" }
+      assert ActiveRecord::Base.connection.table_exists?("horses"), "horses should exist"
     end
 
     def test_down
       LegacyMigration.up
       LegacyMigration.down
-      ActiveSupport::Deprecation.silence { assert !ActiveRecord::Base.connection.table_exists?("horses"), "horses should not exist" }
+      assert !ActiveRecord::Base.connection.table_exists?("horses"), "horses should not exist"
     end
 
     def test_migrate_down_with_table_name_prefix
-      ActiveRecord::Base.table_name_prefix = 'p_'
-      ActiveRecord::Base.table_name_suffix = '_s'
+      ActiveRecord::Base.table_name_prefix = "p_"
+      ActiveRecord::Base.table_name_suffix = "_s"
       migration = InvertibleMigration.new
       migration.migrate(:up)
       assert_nothing_raised { migration.migrate(:down) }
-      ActiveSupport::Deprecation.silence { assert !ActiveRecord::Base.connection.table_exists?("p_horses_s"), "p_horses_s should not exist" }
+      assert !ActiveRecord::Base.connection.table_exists?("p_horses_s"), "p_horses_s should not exist"
     ensure
-      ActiveRecord::Base.table_name_prefix = ActiveRecord::Base.table_name_suffix = ''
+      ActiveRecord::Base.table_name_prefix = ActiveRecord::Base.table_name_suffix = ""
     end
 
     def test_migrations_can_handle_foreign_keys_to_specific_tables
@@ -383,5 +388,22 @@ module ActiveRecord
       end
     end
 
+    def test_up_only
+      InvertibleMigration.new.migrate(:up)
+      horse1 = Horse.create
+      # populates existing horses with oldie = 1 but new ones have default 0
+      UpOnlyMigration.new.migrate(:up)
+      Horse.reset_column_information
+      horse1.reload
+      horse2 = Horse.create
+
+      assert 1, horse1.oldie # created before migration
+      assert 0, horse2.oldie # created after migration
+
+      UpOnlyMigration.new.migrate(:down) # should be no error
+      connection = ActiveRecord::Base.connection
+      assert !connection.column_exists?(:horses, :oldie)
+      Horse.reset_column_information
+    end
   end
 end
diff --git a/activerecord/test/cases/json_attribute_test.rb b/activerecord/test/cases/json_attribute_test.rb
new file mode 100644
index 0000000000..afc39d0420
--- /dev/null
+++ b/activerecord/test/cases/json_attribute_test.rb
@@ -0,0 +1,35 @@
+# frozen_string_literal: true
+
+require "cases/helper"
+require "cases/json_shared_test_cases"
+
+class JsonAttributeTest < ActiveRecord::TestCase
+  include JSONSharedTestCases
+  self.use_transactional_tests = false
+
+  class JsonDataTypeOnText < ActiveRecord::Base
+    self.table_name = "json_data_type"
+
+    attribute :payload,  :json
+    attribute :settings, :json
+
+    store_accessor :settings, :resolution
+  end
+
+  def setup
+    super
+    @connection.create_table("json_data_type") do |t|
+      t.string "payload"
+      t.string "settings"
+    end
+  end
+
+  private
+    def column_type
+      :string
+    end
+
+    def klass
+      JsonDataTypeOnText
+    end
+end
diff --git a/activerecord/test/cases/json_serialization_test.rb b/activerecord/test/cases/json_serialization_test.rb
index a222675918..52fe488cd5 100644
--- a/activerecord/test/cases/json_serialization_test.rb
+++ b/activerecord/test/cases/json_serialization_test.rb
@@ -1,21 +1,23 @@
+# frozen_string_literal: true
+
 require "cases/helper"
-require 'models/contact'
-require 'models/post'
-require 'models/author'
-require 'models/tagging'
-require 'models/tag'
-require 'models/comment'
+require "models/contact"
+require "models/post"
+require "models/author"
+require "models/tagging"
+require "models/tag"
+require "models/comment"
 
 module JsonSerializationHelpers
   private
 
-  def set_include_root_in_json(value)
-    original_root_in_json = ActiveRecord::Base.include_root_in_json
-    ActiveRecord::Base.include_root_in_json = value
-    yield
-  ensure
-    ActiveRecord::Base.include_root_in_json = original_root_in_json
-  end
+    def set_include_root_in_json(value)
+      original_root_in_json = ActiveRecord::Base.include_root_in_json
+      ActiveRecord::Base.include_root_in_json = value
+      yield
+    ensure
+      ActiveRecord::Base.include_root_in_json = original_root_in_json
+    end
 end
 
 class JsonSerializationTest < ActiveRecord::TestCase
@@ -27,18 +29,18 @@ class JsonSerializationTest < ActiveRecord::TestCase
 
   def setup
     @contact = Contact.new(
-      :name        => 'Konata Izumi',
-      :age         => 16,
-      :avatar      => 'binarydata',
-      :created_at  => Time.utc(2006, 8, 1),
-      :awesome     => true,
-      :preferences => { :shows => 'anime' }
+      name: "Konata Izumi",
+      age: 16,
+      avatar: "binarydata",
+      created_at: Time.utc(2006, 8, 1),
+      awesome: true,
+      preferences: { shows: "anime" }
     )
   end
 
   def test_should_demodulize_root_in_json
     set_include_root_in_json(true) do
-      @contact = NamespacedContact.new name: 'whatever'
+      @contact = NamespacedContact.new name: "whatever"
       json = @contact.to_json
       assert_match %r{^\{"namespaced_contact":\{}, json
     end
@@ -51,7 +53,7 @@ class JsonSerializationTest < ActiveRecord::TestCase
       assert_match %r{^\{"contact":\{}, json
       assert_match %r{"name":"Konata Izumi"}, json
       assert_match %r{"age":16}, json
-      assert json.include?(%("created_at":#{ActiveSupport::JSON.encode(Time.utc(2006, 8, 1))}))
+      assert_includes json, %("created_at":#{ActiveSupport::JSON.encode(Time.utc(2006, 8, 1))})
       assert_match %r{"awesome":true}, json
       assert_match %r{"preferences":\{"shows":"anime"\}}, json
     end
@@ -62,28 +64,28 @@ class JsonSerializationTest < ActiveRecord::TestCase
 
     assert_match %r{"name":"Konata Izumi"}, json
     assert_match %r{"age":16}, json
-    assert json.include?(%("created_at":#{ActiveSupport::JSON.encode(Time.utc(2006, 8, 1))}))
+    assert_includes json, %("created_at":#{ActiveSupport::JSON.encode(Time.utc(2006, 8, 1))})
     assert_match %r{"awesome":true}, json
     assert_match %r{"preferences":\{"shows":"anime"\}}, json
   end
 
   def test_should_allow_attribute_filtering_with_only
-    json = @contact.to_json(:only => [:name, :age])
+    json = @contact.to_json(only: [:name, :age])
 
     assert_match %r{"name":"Konata Izumi"}, json
     assert_match %r{"age":16}, json
     assert_no_match %r{"awesome":true}, json
-    assert !json.include?(%("created_at":#{ActiveSupport::JSON.encode(Time.utc(2006, 8, 1))}))
+    assert_not_includes json, %("created_at":#{ActiveSupport::JSON.encode(Time.utc(2006, 8, 1))})
     assert_no_match %r{"preferences":\{"shows":"anime"\}}, json
   end
 
   def test_should_allow_attribute_filtering_with_except
-    json = @contact.to_json(:except => [:name, :age])
+    json = @contact.to_json(except: [:name, :age])
 
     assert_no_match %r{"name":"Konata Izumi"}, json
     assert_no_match %r{"age":16}, json
     assert_match %r{"awesome":true}, json
-    assert json.include?(%("created_at":#{ActiveSupport::JSON.encode(Time.utc(2006, 8, 1))}))
+    assert_includes json, %("created_at":#{ActiveSupport::JSON.encode(Time.utc(2006, 8, 1))})
     assert_match %r{"preferences":\{"shows":"anime"\}}, json
   end
 
@@ -93,16 +95,27 @@ class JsonSerializationTest < ActiveRecord::TestCase
     def @contact.favorite_quote; "Constraints are liberating"; end
 
     # Single method.
-    assert_match %r{"label":"Has cheezburger"}, @contact.to_json(:only => :name, :methods => :label)
+    assert_match %r{"label":"Has cheezburger"}, @contact.to_json(only: :name, methods: :label)
 
     # Both methods.
-    methods_json = @contact.to_json(:only => :name, :methods => [:label, :favorite_quote])
+    methods_json = @contact.to_json(only: :name, methods: [:label, :favorite_quote])
     assert_match %r{"label":"Has cheezburger"}, methods_json
     assert_match %r{"favorite_quote":"Constraints are liberating"}, methods_json
   end
 
+  def test_uses_serializable_hash_with_frozen_hash
+    def @contact.serializable_hash(options = nil)
+      super({ only: %w(name) }.freeze)
+    end
+
+    json = @contact.to_json
+    assert_match %r{"name":"Konata Izumi"}, json
+    assert_no_match %r{awesome}, json
+    assert_no_match %r{age}, json
+  end
+
   def test_uses_serializable_hash_with_only_option
-    def @contact.serializable_hash(options=nil)
+    def @contact.serializable_hash(options = nil)
       super(only: %w(name))
     end
 
@@ -113,7 +126,7 @@ class JsonSerializationTest < ActiveRecord::TestCase
   end
 
   def test_uses_serializable_hash_with_except_option
-    def @contact.serializable_hash(options=nil)
+    def @contact.serializable_hash(options = nil)
       super(except: %w(age))
     end
 
@@ -125,7 +138,7 @@ class JsonSerializationTest < ActiveRecord::TestCase
 
   def test_does_not_include_inheritance_column_from_sti
     @contact = ContactSti.new(@contact.attributes)
-    assert_equal 'ContactSti', @contact.type
+    assert_equal "ContactSti", @contact.type
 
     json = @contact.to_json
     assert_match %r{"name":"Konata Izumi"}, json
@@ -135,9 +148,9 @@ class JsonSerializationTest < ActiveRecord::TestCase
 
   def test_serializable_hash_with_default_except_option_and_excluding_inheritance_column_from_sti
     @contact = ContactSti.new(@contact.attributes)
-    assert_equal 'ContactSti', @contact.type
+    assert_equal "ContactSti", @contact.type
 
-    def @contact.serializable_hash(options={})
+    def @contact.serializable_hash(options = {})
       super({ except: %w(age) }.merge!(options))
     end
 
@@ -149,15 +162,13 @@ class JsonSerializationTest < ActiveRecord::TestCase
   end
 
   def test_serializable_hash_should_not_modify_options_in_argument
-    options = { :only => :name }
-    @contact.serializable_hash(options)
-
-    assert_nil options[:except]
+    options = { only: :name }.freeze
+    assert_nothing_raised { @contact.serializable_hash(options) }
   end
 end
 
 class DatabaseConnectedJsonEncodingTest < ActiveRecord::TestCase
-  fixtures :authors, :posts, :comments, :tags, :taggings
+  fixtures :authors, :author_addresses, :posts, :comments, :tags, :taggings
 
   include JsonSerializationHelpers
 
@@ -167,7 +178,7 @@ class DatabaseConnectedJsonEncodingTest < ActiveRecord::TestCase
   end
 
   def test_includes_uses_association_name
-    json = @david.to_json(:include => :posts)
+    json = @david.to_json(include: :posts)
 
     assert_match %r{"posts":\[}, json
 
@@ -183,7 +194,7 @@ class DatabaseConnectedJsonEncodingTest < ActiveRecord::TestCase
   end
 
   def test_includes_uses_association_name_and_applies_attribute_filters
-    json = @david.to_json(:include => { :posts => { :only => :title } })
+    json = @david.to_json(include: { posts: { only: :title } })
 
     assert_match %r{"name":"David"}, json
     assert_match %r{"posts":\[}, json
@@ -196,7 +207,7 @@ class DatabaseConnectedJsonEncodingTest < ActiveRecord::TestCase
   end
 
   def test_includes_fetches_second_level_associations
-    json = @david.to_json(:include => { :posts => { :include => { :comments => { :only => :body } } } })
+    json = @david.to_json(include: { posts: { include: { comments: { only: :body } } } })
 
     assert_match %r{"name":"David"}, json
     assert_match %r{"posts":\[}, json
@@ -209,12 +220,12 @@ class DatabaseConnectedJsonEncodingTest < ActiveRecord::TestCase
 
   def test_includes_fetches_nth_level_associations
     json = @david.to_json(
-      :include => {
-        :posts => {
-          :include => {
-            :taggings => {
-              :include => {
-                :tag => { :only => :name }
+      include: {
+        posts: {
+          include: {
+            taggings: {
+              include: {
+                tag: { only: :name }
               }
             }
           }
@@ -230,8 +241,8 @@ class DatabaseConnectedJsonEncodingTest < ActiveRecord::TestCase
 
   def test_includes_doesnt_merge_opts_from_base
     json = @david.to_json(
-      :only => :id,
-      :include => :posts
+      only: :id,
+      include: :posts
     )
 
     assert_match %{"title":"Welcome to the weblog"}, json
@@ -239,11 +250,11 @@ class DatabaseConnectedJsonEncodingTest < ActiveRecord::TestCase
 
   def test_should_not_call_methods_on_associations_that_dont_respond
     def @david.favorite_quote; "Constraints are liberating"; end
-    json = @david.to_json(:include => :posts, :methods => :favorite_quote)
+    json = @david.to_json(include: :posts, methods: :favorite_quote)
 
     assert !@david.posts.first.respond_to?(:favorite_quote)
     assert_match %r{"favorite_quote":"Constraints are liberating"}, json
-    assert_equal %r{"favorite_quote":}.match(json).size, 1
+    assert_equal 1, %r{"favorite_quote":}.match(json).size
   end
 
   def test_should_allow_only_option_for_list_of_authors
@@ -267,15 +278,15 @@ class DatabaseConnectedJsonEncodingTest < ActiveRecord::TestCase
   def test_should_allow_includes_for_list_of_authors
     authors = [@david, @mary]
     json = ActiveSupport::JSON.encode(authors,
-      :only => :name,
-      :include => {
-        :posts => { :only => :id }
+      only: :name,
+      include: {
+        posts: { only: :id }
       }
     )
 
     ['"name":"David"', '"posts":[', '{"id":1}', '{"id":2}', '{"id":4}',
      '{"id":5}', '{"id":6}', '"name":"Mary"', '"posts":[', '{"id":7}', '{"id":9}'].each do |fragment|
-      assert json.include?(fragment), json
+       assert_includes json, fragment, json
      end
   end
 
diff --git a/activerecord/test/cases/json_shared_test_cases.rb b/activerecord/test/cases/json_shared_test_cases.rb
new file mode 100644
index 0000000000..b0c0f2c283
--- /dev/null
+++ b/activerecord/test/cases/json_shared_test_cases.rb
@@ -0,0 +1,269 @@
+# frozen_string_literal: true
+
+require "support/schema_dumping_helper"
+
+module JSONSharedTestCases
+  include SchemaDumpingHelper
+
+  class JsonDataType < ActiveRecord::Base
+    self.table_name = "json_data_type"
+
+    store_accessor :settings, :resolution
+  end
+
+  def setup
+    @connection = ActiveRecord::Base.connection
+  end
+
+  def teardown
+    @connection.drop_table :json_data_type, if_exists: true
+    klass.reset_column_information
+  end
+
+  def test_column
+    column = klass.columns_hash["payload"]
+    assert_equal column_type, column.type
+    assert_type_match column_type, column.sql_type
+
+    type = klass.type_for_attribute("payload")
+    assert_not type.binary?
+  end
+
+  def test_change_table_supports_json
+    @connection.change_table("json_data_type") do |t|
+      t.public_send column_type, "users"
+    end
+    klass.reset_column_information
+    column = klass.columns_hash["users"]
+    assert_equal column_type, column.type
+    assert_type_match column_type, column.sql_type
+  end
+
+  def test_schema_dumping
+    output = dump_table_schema("json_data_type")
+    assert_match(/t\.#{column_type}\s+"settings"/, output)
+  end
+
+  def test_cast_value_on_write
+    x = klass.new(payload: { "string" => "foo", :symbol => :bar })
+    assert_equal({ "string" => "foo", :symbol => :bar }, x.payload_before_type_cast)
+    assert_equal({ "string" => "foo", "symbol" => "bar" }, x.payload)
+    x.save!
+    assert_equal({ "string" => "foo", "symbol" => "bar" }, x.reload.payload)
+  end
+
+  def test_type_cast_json
+    type = klass.type_for_attribute("payload")
+
+    data = '{"a_key":"a_value"}'
+    hash = type.deserialize(data)
+    assert_equal({ "a_key" => "a_value" }, hash)
+    assert_equal({ "a_key" => "a_value" }, type.deserialize(data))
+
+    assert_equal({}, type.deserialize("{}"))
+    assert_equal({ "key" => nil }, type.deserialize('{"key": null}'))
+    assert_equal({ "c" => "}", '"a"' => 'b "a b' }, type.deserialize(%q({"c":"}", "\"a\"":"b \"a b"})))
+  end
+
+  def test_rewrite
+    @connection.execute(insert_statement_per_database('{"k":"v"}'))
+    x = klass.first
+    x.payload = { '"a\'' => "b" }
+    assert x.save!
+  end
+
+  def test_select
+    @connection.execute(insert_statement_per_database('{"k":"v"}'))
+    x = klass.first
+    assert_equal({ "k" => "v" }, x.payload)
+  end
+
+  def test_select_multikey
+    @connection.execute(insert_statement_per_database('{"k1":"v1", "k2":"v2", "k3":[1,2,3]}'))
+    x = klass.first
+    assert_equal({ "k1" => "v1", "k2" => "v2", "k3" => [1, 2, 3] }, x.payload)
+  end
+
+  def test_null_json
+    @connection.execute(insert_statement_per_database("null"))
+    x = klass.first
+    assert_nil(x.payload)
+  end
+
+  def test_select_nil_json_after_create
+    json = klass.create!(payload: nil)
+    x = klass.where(payload: nil).first
+    assert_equal(json, x)
+  end
+
+  def test_select_nil_json_after_update
+    json = klass.create!(payload: "foo")
+    x = klass.where(payload: nil).first
+    assert_nil(x)
+
+    json.update_attributes(payload: nil)
+    x = klass.where(payload: nil).first
+    assert_equal(json.reload, x)
+  end
+
+  def test_select_array_json_value
+    @connection.execute(insert_statement_per_database('["v0",{"k1":"v1"}]'))
+    x = klass.first
+    assert_equal(["v0", { "k1" => "v1" }], x.payload)
+  end
+
+  def test_rewrite_array_json_value
+    @connection.execute(insert_statement_per_database('["v0",{"k1":"v1"}]'))
+    x = klass.first
+    x.payload = ["v1", { "k2" => "v2" }, "v3"]
+    assert x.save!
+  end
+
+  def test_with_store_accessors
+    x = klass.new(resolution: "320×480")
+    assert_equal "320×480", x.resolution
+
+    x.save!
+    x = klass.first
+    assert_equal "320×480", x.resolution
+
+    x.resolution = "640×1136"
+    x.save!
+
+    x = klass.first
+    assert_equal "640×1136", x.resolution
+  end
+
+  def test_duplication_with_store_accessors
+    x = klass.new(resolution: "320×480")
+    assert_equal "320×480", x.resolution
+
+    y = x.dup
+    assert_equal "320×480", y.resolution
+  end
+
+  def test_yaml_round_trip_with_store_accessors
+    x = klass.new(resolution: "320×480")
+    assert_equal "320×480", x.resolution
+
+    y = YAML.load(YAML.dump(x))
+    assert_equal "320×480", y.resolution
+  end
+
+  def test_changes_in_place
+    json = klass.new
+    assert_not json.changed?
+
+    json.payload = { "one" => "two" }
+    assert json.changed?
+    assert json.payload_changed?
+
+    json.save!
+    assert_not json.changed?
+
+    json.payload["three"] = "four"
+    assert json.payload_changed?
+
+    json.save!
+    json.reload
+
+    assert_equal({ "one" => "two", "three" => "four" }, json.payload)
+    assert_not json.changed?
+  end
+
+  def test_changes_in_place_ignores_key_order
+    json = klass.new
+    assert_not json.changed?
+
+    json.payload = { "three" => "four", "one" => "two" }
+    json.save!
+    json.reload
+
+    json.payload = { "three" => "four", "one" => "two" }
+    assert_not json.changed?
+
+    json.payload = [{ "three" => "four", "one" => "two" }, { "seven" => "eight", "five" => "six" }]
+    json.save!
+    json.reload
+
+    json.payload = [{ "three" => "four", "one" => "two" }, { "seven" => "eight", "five" => "six" }]
+    assert_not json.changed?
+  end
+
+  def test_changes_in_place_with_ruby_object
+    time = Time.now.utc
+    json = klass.create!(payload: time)
+
+    json.reload
+    assert_not json.changed?
+
+    json.payload = time
+    assert_not json.changed?
+  end
+
+  def test_assigning_string_literal
+    json = klass.create!(payload: "foo")
+    assert_equal "foo", json.payload
+  end
+
+  def test_assigning_number
+    json = klass.create!(payload: 1.234)
+    assert_equal 1.234, json.payload
+  end
+
+  def test_assigning_boolean
+    json = klass.create!(payload: true)
+    assert_equal true, json.payload
+  end
+
+  def test_not_compatible_with_serialize_json
+    new_klass = Class.new(klass) do
+      serialize :payload, JSON
+    end
+    assert_raises(ActiveRecord::AttributeMethods::Serialization::ColumnNotSerializableError) do
+      new_klass.new
+    end
+  end
+
+  class MySettings
+    def initialize(hash); @hash = hash end
+    def to_hash; @hash end
+    def self.load(hash); new(hash) end
+    def self.dump(object); object.to_hash end
+  end
+
+  def test_json_with_serialized_attributes
+    new_klass = Class.new(klass) do
+      serialize :settings, MySettings
+    end
+
+    new_klass.create!(settings: MySettings.new("one" => "two"))
+    record = new_klass.first
+
+    assert_instance_of MySettings, record.settings
+    assert_equal({ "one" => "two" }, record.settings.to_hash)
+
+    record.settings = MySettings.new("three" => "four")
+    record.save!
+
+    assert_equal({ "three" => "four" }, record.reload.settings.to_hash)
+  end
+
+  private
+    def klass
+      JsonDataType
+    end
+
+    def assert_type_match(type, sql_type)
+      native_type = ActiveRecord::Base.connection.native_database_types[type][:name]
+      assert_match %r(\A#{native_type}\b), sql_type
+    end
+
+    def insert_statement_per_database(values)
+      if current_adapter?(:OracleAdapter)
+        "insert into json_data_type (id, payload) VALUES (json_data_type_seq.nextval, '#{values}')"
+      else
+        "insert into json_data_type (payload) VALUES ('#{values}')"
+      end
+    end
+end
diff --git a/activerecord/test/cases/locking_test.rb b/activerecord/test/cases/locking_test.rb
index 9fc0041892..3701be4b11 100644
--- a/activerecord/test/cases/locking_test.rb
+++ b/activerecord/test/cases/locking_test.rb
@@ -1,24 +1,26 @@
-require 'thread'
+# frozen_string_literal: true
+
+require "thread"
 require "cases/helper"
-require 'models/person'
-require 'models/job'
-require 'models/reader'
-require 'models/ship'
-require 'models/legacy_thing'
-require 'models/personal_legacy_thing'
-require 'models/reference'
-require 'models/string_key_object'
-require 'models/car'
-require 'models/bulb'
-require 'models/engine'
-require 'models/wheel'
-require 'models/treasure'
+require "models/person"
+require "models/job"
+require "models/reader"
+require "models/ship"
+require "models/legacy_thing"
+require "models/personal_legacy_thing"
+require "models/reference"
+require "models/string_key_object"
+require "models/car"
+require "models/bulb"
+require "models/engine"
+require "models/wheel"
+require "models/treasure"
 
 class LockWithoutDefault < ActiveRecord::Base; end
 
 class LockWithCustomColumnWithoutDefault < ActiveRecord::Base
   self.table_name = :lock_without_defaults_cust
-  self.column_defaults # to test @column_defaults caching.
+  column_defaults # to test @column_defaults caching.
   self.locking_column = :custom_lock_version
 end
 
@@ -33,7 +35,7 @@ class OptimisticLockingTest < ActiveRecord::TestCase
     p1 = Person.find(1)
     assert_equal 0, p1.lock_version
 
-    p1.first_name = 'anika2'
+    p1.first_name = "anika2"
     p1.save!
 
     assert_equal 1, p1.lock_version
@@ -45,12 +47,12 @@ class OptimisticLockingTest < ActiveRecord::TestCase
     assert_equal 0, s1.lock_version
     assert_equal 0, s2.lock_version
 
-    s1.name = 'updated record'
+    s1.name = "updated record"
     s1.save!
     assert_equal 1, s1.lock_version
     assert_equal 0, s2.lock_version
 
-    s2.name = 'doubly updated record'
+    s2.name = "doubly updated record"
     assert_raise(ActiveRecord::StaleObjectError) { s2.save! }
   end
 
@@ -60,7 +62,7 @@ class OptimisticLockingTest < ActiveRecord::TestCase
     assert_equal 0, s1.lock_version
     assert_equal 0, s2.lock_version
 
-    s1.name = 'updated record'
+    s1.name = "updated record"
     s1.save!
     assert_equal 1, s1.lock_version
     assert_equal 0, s2.lock_version
@@ -78,12 +80,12 @@ class OptimisticLockingTest < ActiveRecord::TestCase
     assert_equal 0, p1.lock_version
     assert_equal 0, p2.lock_version
 
-    p1.first_name = 'stu'
+    p1.first_name = "stu"
     p1.save!
     assert_equal 1, p1.lock_version
     assert_equal 0, p2.lock_version
 
-    p2.first_name = 'sue'
+    p2.first_name = "sue"
     assert_raise(ActiveRecord::StaleObjectError) { p2.save! }
   end
 
@@ -94,7 +96,7 @@ class OptimisticLockingTest < ActiveRecord::TestCase
     assert_equal 0, p1.lock_version
     assert_equal 0, p2.lock_version
 
-    p1.first_name = 'stu'
+    p1.first_name = "stu"
     p1.save!
     assert_equal 1, p1.lock_version
     assert_equal 0, p2.lock_version
@@ -113,66 +115,64 @@ class OptimisticLockingTest < ActiveRecord::TestCase
     assert_equal 0, p1.lock_version
     assert_equal 0, p2.lock_version
 
-    p1.first_name = 'stu'
+    p1.first_name = "stu"
     p1.save!
     assert_equal 1, p1.lock_version
     assert_equal 0, p2.lock_version
 
-    p2.first_name = 'sue'
+    p2.first_name = "sue"
     assert_raise(ActiveRecord::StaleObjectError) { p2.save! }
-    p2.first_name = 'sue2'
+    p2.first_name = "sue2"
     assert_raise(ActiveRecord::StaleObjectError) { p2.save! }
   end
 
   def test_lock_new
-    p1 = Person.new(:first_name => 'anika')
+    p1 = Person.new(first_name: "anika")
     assert_equal 0, p1.lock_version
 
-    p1.first_name = 'anika2'
+    p1.first_name = "anika2"
     p1.save!
     p2 = Person.find(p1.id)
     assert_equal 0, p1.lock_version
     assert_equal 0, p2.lock_version
 
-    p1.first_name = 'anika3'
+    p1.first_name = "anika3"
     p1.save!
     assert_equal 1, p1.lock_version
     assert_equal 0, p2.lock_version
 
-    p2.first_name = 'sue'
+    p2.first_name = "sue"
     assert_raise(ActiveRecord::StaleObjectError) { p2.save! }
   end
 
   def test_lock_exception_record
-    p1 = Person.new(:first_name => 'mira')
+    p1 = Person.new(first_name: "mira")
     assert_equal 0, p1.lock_version
 
-    p1.first_name = 'mira2'
+    p1.first_name = "mira2"
     p1.save!
     p2 = Person.find(p1.id)
     assert_equal 0, p1.lock_version
     assert_equal 0, p2.lock_version
 
-    p1.first_name = 'mira3'
+    p1.first_name = "mira3"
     p1.save!
 
-    p2.first_name = 'sue'
+    p2.first_name = "sue"
     error = assert_raise(ActiveRecord::StaleObjectError) { p2.save! }
     assert_equal(error.record.object_id, p2.object_id)
   end
 
-  def test_lock_new_with_nil
-    p1 = Person.new(:first_name => 'anika')
-    p1.save!
-    p1.lock_version = nil # simulate bad fixture or column with no default
+  def test_lock_new_when_explicitly_passing_nil
+    p1 = Person.new(first_name: "anika", lock_version: nil)
     p1.save!
-    assert_equal 1, p1.lock_version
+    assert_equal 0, p1.lock_version
   end
 
-  def test_lock_new_when_explicitly_passing_nil
-    p1 = Person.new(:first_name => 'anika', lock_version: nil)
+  def test_lock_new_when_explicitly_passing_value
+    p1 = Person.new(first_name: "Douglas Adams", lock_version: 42)
     p1.save!
-    assert_equal 0, p1.lock_version
+    assert_equal 42, p1.lock_version
   end
 
   def test_touch_existing_lock
@@ -181,18 +181,32 @@ class OptimisticLockingTest < ActiveRecord::TestCase
 
     p1.touch
     assert_equal 1, p1.lock_version
+    assert_not p1.changed?, "Changes should have been cleared"
   end
 
   def test_touch_stale_object
-    person = Person.create!(first_name: 'Mehmet Emin')
+    person = Person.create!(first_name: "Mehmet Emin")
     stale_person = Person.find(person.id)
-    person.update_attribute(:gender, 'M')
+    person.update_attribute(:gender, "M")
 
     assert_raises(ActiveRecord::StaleObjectError) do
       stale_person.touch
     end
   end
 
+  def test_explicit_update_lock_column_raise_error
+    person = Person.find(1)
+
+    assert_raises(ActiveRecord::StaleObjectError) do
+      person.first_name = "Douglas Adams"
+      person.lock_version = 42
+
+      assert person.lock_version_changed?
+
+      person.save
+    end
+  end
+
   def test_lock_column_name_existing
     t1 = LegacyThing.find(1)
     t2 = LegacyThing.find(1)
@@ -209,11 +223,11 @@ class OptimisticLockingTest < ActiveRecord::TestCase
   end
 
   def test_lock_column_is_mass_assignable
-    p1 = Person.create(:first_name => 'bianca')
+    p1 = Person.create(first_name: "bianca")
     assert_equal 0, p1.lock_version
     assert_equal p1.lock_version, Person.new(p1.attributes).lock_version
 
-    p1.first_name = 'bianca2'
+    p1.first_name = "bianca2"
     p1.save!
     assert_equal 1, p1.lock_version
     assert_equal p1.lock_version, Person.new(p1.attributes).lock_version
@@ -221,28 +235,144 @@ class OptimisticLockingTest < ActiveRecord::TestCase
 
   def test_lock_without_default_sets_version_to_zero
     t1 = LockWithoutDefault.new
+
     assert_equal 0, t1.lock_version
+    assert_nil t1.lock_version_before_type_cast
+
+    t1.save!
+    t1.reload
+
+    assert_equal 0, t1.lock_version
+    assert_equal 0, t1.lock_version_before_type_cast
+  end
+
+  def test_touch_existing_lock_without_default_should_work_with_null_in_the_database
+    ActiveRecord::Base.connection.execute("INSERT INTO lock_without_defaults(title) VALUES('title1')")
+    t1 = LockWithoutDefault.last
 
-    t1.save
-    t1 = LockWithoutDefault.find(t1.id)
     assert_equal 0, t1.lock_version
+    assert_nil t1.lock_version_before_type_cast
+
+    t1.touch
+
+    assert_equal 1, t1.lock_version
+  end
+
+  def test_touch_stale_object_with_lock_without_default
+    t1 = LockWithoutDefault.create!(title: "title1")
+    stale_object = LockWithoutDefault.find(t1.id)
+
+    t1.update!(title: "title2")
+
+    assert_raises(ActiveRecord::StaleObjectError) do
+      stale_object.touch
+    end
+  end
+
+  def test_lock_without_default_should_work_with_null_in_the_database
+    ActiveRecord::Base.connection.execute("INSERT INTO lock_without_defaults(title) VALUES('title1')")
+    t1 = LockWithoutDefault.last
+    t2 = LockWithoutDefault.find(t1.id)
+
+    assert_equal 0, t1.lock_version
+    assert_nil t1.lock_version_before_type_cast
+    assert_equal 0, t2.lock_version
+    assert_nil t2.lock_version_before_type_cast
+
+    t1.title = "new title1"
+    t2.title = "new title2"
+
+    assert_nothing_raised { t1.save! }
+    assert_equal 1, t1.lock_version
+    assert_equal "new title1", t1.title
+
+    assert_raise(ActiveRecord::StaleObjectError) { t2.save! }
+    assert_equal 0, t2.lock_version
+    assert_equal "new title2", t2.title
+  end
+
+  def test_lock_without_default_queries_count
+    t1 = LockWithoutDefault.create(title: "title1")
+
+    assert_equal "title1", t1.title
+    assert_equal 0, t1.lock_version
+
+    assert_queries(1) { t1.update(title: "title2") }
+
+    t1.reload
+    assert_equal "title2", t1.title
+    assert_equal 1, t1.lock_version
+
+    t2 = LockWithoutDefault.new(title: "title1")
+
+    assert_queries(1) { t2.save! }
+
+    t2.reload
+    assert_equal "title1", t2.title
+    assert_equal 0, t2.lock_version
   end
 
   def test_lock_with_custom_column_without_default_sets_version_to_zero
     t1 = LockWithCustomColumnWithoutDefault.new
+
     assert_equal 0, t1.custom_lock_version
     assert_nil t1.custom_lock_version_before_type_cast
 
     t1.save!
     t1.reload
+
     assert_equal 0, t1.custom_lock_version
-    assert [0, "0"].include?(t1.custom_lock_version_before_type_cast)
+    assert_equal 0, t1.custom_lock_version_before_type_cast
+  end
+
+  def test_lock_with_custom_column_without_default_should_work_with_null_in_the_database
+    ActiveRecord::Base.connection.execute("INSERT INTO lock_without_defaults_cust(title) VALUES('title1')")
+
+    t1 = LockWithCustomColumnWithoutDefault.last
+    t2 = LockWithCustomColumnWithoutDefault.find(t1.id)
+
+    assert_equal 0, t1.custom_lock_version
+    assert_nil t1.custom_lock_version_before_type_cast
+    assert_equal 0, t2.custom_lock_version
+    assert_nil t2.custom_lock_version_before_type_cast
+
+    t1.title = "new title1"
+    t2.title = "new title2"
+
+    assert_nothing_raised { t1.save! }
+    assert_equal 1, t1.custom_lock_version
+    assert_equal "new title1", t1.title
+
+    assert_raise(ActiveRecord::StaleObjectError) { t2.save! }
+    assert_equal 0, t2.custom_lock_version
+    assert_equal "new title2", t2.title
+  end
+
+  def test_lock_with_custom_column_without_default_queries_count
+    t1 = LockWithCustomColumnWithoutDefault.create(title: "title1")
+
+    assert_equal "title1", t1.title
+    assert_equal 0, t1.custom_lock_version
+
+    assert_queries(1) { t1.update(title: "title2") }
+
+    t1.reload
+    assert_equal "title2", t1.title
+    assert_equal 1, t1.custom_lock_version
+
+    t2 = LockWithCustomColumnWithoutDefault.new(title: "title1")
+
+    assert_queries(1) { t2.save! }
+
+    t2.reload
+    assert_equal "title1", t2.title
+    assert_equal 0, t2.custom_lock_version
   end
 
   def test_readonly_attributes
-    assert_equal Set.new([ 'name' ]), ReadonlyNameShip.readonly_attributes
+    assert_equal Set.new([ "name" ]), ReadonlyNameShip.readonly_attributes
 
-    s = ReadonlyNameShip.create(:name => "unchangeable name")
+    s = ReadonlyNameShip.create(name: "unchangeable name")
     s.reload
     assert_equal "unchangeable name", s.name
 
@@ -261,7 +391,7 @@ class OptimisticLockingTest < ActiveRecord::TestCase
   # is nothing else being updated.
   def test_update_without_attributes_does_not_only_update_lock_version
     assert_nothing_raised do
-      p1 = Person.create!(:first_name => 'anika')
+      p1 = Person.create!(first_name: "anika")
       lock_version = p1.lock_version
       p1.save
       p1.reload
@@ -269,20 +399,52 @@ class OptimisticLockingTest < ActiveRecord::TestCase
     end
   end
 
+  def test_counter_cache_with_touch_and_lock_version
+    car = Car.create!
+
+    assert_equal 0, car.wheels_count
+    assert_equal 0, car.lock_version
+
+    previously_car_updated_at = car.updated_at
+    travel(2.second) do
+      Wheel.create!(wheelable: car)
+    end
+
+    assert_equal 1, car.reload.wheels_count
+    assert_not_equal previously_car_updated_at, car.updated_at
+    assert_equal 1, car.lock_version
+
+    previously_car_updated_at = car.updated_at
+    car.wheels.first.update(size: 42)
+
+    assert_equal 1, car.reload.wheels_count
+    assert_not_equal previously_car_updated_at, car.updated_at
+    assert_equal 2, car.lock_version
+
+    previously_car_updated_at = car.updated_at
+    travel(2.second) do
+      car.wheels.first.destroy!
+    end
+
+    assert_equal 0, car.reload.wheels_count
+    assert_not_equal previously_car_updated_at, car.updated_at
+    assert_equal 3, car.lock_version
+  end
+
   def test_polymorphic_destroy_with_dependencies_and_lock_version
     car = Car.create!
 
-    assert_difference 'car.wheels.count'  do
-      car.wheels << Wheel.create!
+    assert_difference "car.wheels.count"  do
+      car.wheels.create
     end
-    assert_difference 'car.wheels.count', -1  do
+    assert_difference "car.wheels.count", -1  do
       car.reload.destroy
     end
     assert car.destroyed?
   end
 
   def test_removing_has_and_belongs_to_many_associations_upon_destroy
-    p = RichPerson.create! first_name: 'Jon'
+    p = RichPerson.create! first_name: "Jon"
     p.treasures.create!
     assert !p.treasures.empty?
     p.destroy
@@ -306,7 +468,7 @@ class OptimisticLockingWithSchemaChangeTest < ActiveRecord::TestCase
   # of a test (see test_increment_counter_*).
   self.use_transactional_tests = false
 
-  { :lock_version => Person, :custom_lock_version => LegacyThing }.each do |name, model|
+  { lock_version: Person, custom_lock_version: LegacyThing }.each do |name, model|
     define_method("test_increment_counter_updates_#{name}") do
       counter_test model, 1 do |id|
         model.increment_counter :test_count, id
@@ -321,7 +483,7 @@ class OptimisticLockingWithSchemaChangeTest < ActiveRecord::TestCase
 
     define_method("test_update_counters_updates_#{name}") do
       counter_test model, 1 do |id|
-        model.update_counters id, :test_count => 1
+        model.update_counters id, test_count: 1
       end
     end
   end
@@ -329,13 +491,13 @@ class OptimisticLockingWithSchemaChangeTest < ActiveRecord::TestCase
   # See Lighthouse ticket #1966
   def test_destroy_dependents
     # Establish dependent relationship between Person and PersonalLegacyThing
-    add_counter_column_to(Person, 'personal_legacy_things_count')
+    add_counter_column_to(Person, "personal_legacy_things_count")
     PersonalLegacyThing.reset_column_information
 
     # Make sure that counter incrementing doesn't cause problems
-    p1 = Person.new(:first_name => 'fjord')
+    p1 = Person.new(first_name: "fjord")
     p1.save!
-    t = PersonalLegacyThing.new(:person => p1)
+    t = PersonalLegacyThing.new(person: p1)
     t.save!
     p1.reload
     assert_equal 1, p1.personal_legacy_things_count
@@ -344,14 +506,39 @@ class OptimisticLockingWithSchemaChangeTest < ActiveRecord::TestCase
     assert_raises(ActiveRecord::RecordNotFound) { Person.find(p1.id) }
     assert_raises(ActiveRecord::RecordNotFound) { PersonalLegacyThing.find(t.id) }
   ensure
-    remove_counter_column_from(Person, 'personal_legacy_things_count')
+    remove_counter_column_from(Person, "personal_legacy_things_count")
     PersonalLegacyThing.reset_column_information
   end
 
+  def test_destroy_existing_object_with_locking_column_value_null_in_the_database
+    ActiveRecord::Base.connection.execute("INSERT INTO lock_without_defaults(title) VALUES('title1')")
+    t1 = LockWithoutDefault.last
+
+    assert_equal 0, t1.lock_version
+    assert_nil t1.lock_version_before_type_cast
+
+    t1.destroy
+
+    assert t1.destroyed?
+  end
+
+  def test_destroy_stale_object
+    t1 = LockWithoutDefault.create!(title: "title1")
+    stale_object = LockWithoutDefault.find(t1.id)
+
+    t1.update!(title: "title2")
+
+    assert_raises(ActiveRecord::StaleObjectError) do
+      stale_object.destroy!
+    end
+
+    refute stale_object.destroyed?
+  end
+
   private
 
-    def add_counter_column_to(model, col='test_count')
-      model.connection.add_column model.table_name, col, :integer, :null => false, :default => 0
+    def add_counter_column_to(model, col = "test_count")
+      model.connection.add_column model.table_name, col, :integer, null: false, default: 0
       model.reset_column_information
     end
 
@@ -374,7 +561,6 @@ class OptimisticLockingWithSchemaChangeTest < ActiveRecord::TestCase
     end
 end
 
-
 # TODO: test against the generated SQL since testing locking behavior itself
 # is so cumbersome. Will deadlock Ruby threads if the underlying db.execute
 # blocks, so separate script called by Kernel#system is needed.
@@ -411,34 +597,37 @@ unless in_memory_db?
       end
     end
 
-    # Locking a record reloads it.
-    def test_sane_lock_method
+    def test_lock_does_not_raise_when_the_object_is_not_dirty
+      person = Person.find 1
       assert_nothing_raised do
-        Person.transaction do
-          person = Person.find 1
-          old, person.first_name = person.first_name, 'fooman'
-          person.lock!
-          assert_equal old, person.first_name
-        end
+        person.lock!
+      end
+    end
+
+    def test_lock_raises_when_the_record_is_dirty
+      person = Person.find 1
+      person.first_name = "fooman"
+      assert_raises(RuntimeError) do
+        person.lock!
       end
     end
 
     def test_with_lock_commits_transaction
       person = Person.find 1
       person.with_lock do
-        person.first_name = 'fooman'
+        person.first_name = "fooman"
         person.save!
       end
-      assert_equal 'fooman', person.reload.first_name
+      assert_equal "fooman", person.reload.first_name
     end
 
     def test_with_lock_rolls_back_transaction
       person = Person.find 1
       old = person.first_name
       person.with_lock do
-        person.first_name = 'fooman'
+        person.first_name = "fooman"
         person.save!
-        raise 'oops'
+        raise "oops"
       end rescue nil
       assert_equal old, person.reload.first_name
     end
@@ -448,46 +637,44 @@ unless in_memory_db?
         Person.transaction do
           person = Person.find(1)
           assert_sql(/LIMIT \$?\d FOR SHARE NOWAIT/) do
-            person.lock!('FOR SHARE NOWAIT')
+            person.lock!("FOR SHARE NOWAIT")
           end
         end
       end
     end
 
-    if current_adapter?(:PostgreSQLAdapter, :OracleAdapter)
-      def test_no_locks_no_wait
-        first, second = duel { Person.find 1 }
-        assert first.end > second.end
-      end
+    def test_no_locks_no_wait
+      first, second = duel { Person.find 1 }
+      assert first.end > second.end
+    end
 
-      protected
-        def duel(zzz = 5)
-          t0, t1, t2, t3 = nil, nil, nil, nil
-
-          a = Thread.new do
-            t0 = Time.now
-            Person.transaction do
-              yield
-              sleep zzz       # block thread 2 for zzz seconds
-            end
-            t1 = Time.now
-          end
+    private
+      def duel(zzz = 5)
+        t0, t1, t2, t3 = nil, nil, nil, nil
 
-          b = Thread.new do
-            sleep zzz / 2.0   # ensure thread 1 tx starts first
-            t2 = Time.now
-            Person.transaction { yield }
-            t3 = Time.now
+        a = Thread.new do
+          t0 = Time.now
+          Person.transaction do
+            yield
+            sleep zzz       # block thread 2 for zzz seconds
           end
+          t1 = Time.now
+        end
 
-          a.join
-          b.join
-
-          assert t1 > t0 + zzz
-          assert t2 > t0
-          assert t3 > t2
-          [t0.to_f..t1.to_f, t2.to_f..t3.to_f]
+        b = Thread.new do
+          sleep zzz / 2.0   # ensure thread 1 tx starts first
+          t2 = Time.now
+          Person.transaction { yield }
+          t3 = Time.now
         end
-    end
+
+        a.join
+        b.join
+
+        assert t1 > t0 + zzz
+        assert t2 > t0
+        assert t3 > t2
+        [t0.to_f..t1.to_f, t2.to_f..t3.to_f]
+      end
   end
 end
diff --git a/activerecord/test/cases/log_subscriber_test.rb b/activerecord/test/cases/log_subscriber_test.rb
index c97960a412..e2742ed33e 100644
--- a/activerecord/test/cases/log_subscriber_test.rb
+++ b/activerecord/test/cases/log_subscriber_test.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require "cases/helper"
 require "models/binary"
 require "models/developer"
@@ -21,6 +23,7 @@ class LogSubscriberTest < ActiveRecord::TestCase
       TRANSACTION: REGEXP_CYAN,
       OTHER: REGEXP_MAGENTA
   }
+  Event = Struct.new(:duration, :payload)
 
   class TestDebugLogSubscriber < ActiveRecord::LogSubscriber
     attr_reader :debugs
@@ -30,8 +33,9 @@ class LogSubscriberTest < ActiveRecord::TestCase
       super
     end
 
-    def debug message
-      @debugs << message
+    def debug(progname = nil, &block)
+      @debugs << progname
+      super
     end
   end
 
@@ -55,25 +59,22 @@ class LogSubscriberTest < ActiveRecord::TestCase
   end
 
   def test_schema_statements_are_ignored
-    event = Struct.new(:duration, :payload)
-
     logger = TestDebugLogSubscriber.new
     assert_equal 0, logger.debugs.length
 
-    logger.sql(event.new(0, sql: 'hi mom!'))
+    logger.sql(Event.new(0.9, sql: "hi mom!"))
     assert_equal 1, logger.debugs.length
 
-    logger.sql(event.new(0, sql: 'hi mom!', name: 'foo'))
+    logger.sql(Event.new(0.9, sql: "hi mom!", name: "foo"))
     assert_equal 2, logger.debugs.length
 
-    logger.sql(event.new(0, sql: 'hi mom!', name: 'SCHEMA'))
+    logger.sql(Event.new(0.9, sql: "hi mom!", name: "SCHEMA"))
     assert_equal 2, logger.debugs.length
   end
 
   def test_sql_statements_are_not_squeezed
-    event = Struct.new(:duration, :payload)
     logger = TestDebugLogSubscriber.new
-    logger.sql(event.new(0, sql: 'ruby   rails'))
+    logger.sql(Event.new(0.9, sql: "ruby   rails"))
     assert_match(/ruby   rails/, logger.debugs.first)
   end
 
@@ -86,56 +87,51 @@ class LogSubscriberTest < ActiveRecord::TestCase
   end
 
   def test_basic_query_logging_coloration
-    event = Struct.new(:duration, :payload)
     logger = TestDebugLogSubscriber.new
     logger.colorize_logging = true
     SQL_COLORINGS.each do |verb, color_regex|
-      logger.sql(event.new(0, sql: verb.to_s))
+      logger.sql(Event.new(0.9, sql: verb.to_s))
       assert_match(/#{REGEXP_BOLD}#{color_regex}#{verb}#{REGEXP_CLEAR}/i, logger.debugs.last)
     end
   end
 
   def test_basic_payload_name_logging_coloration_generic_sql
-    event = Struct.new(:duration, :payload)
     logger = TestDebugLogSubscriber.new
     logger.colorize_logging = true
     SQL_COLORINGS.each do |verb, _|
-      logger.sql(event.new(0, sql: verb.to_s))
-      assert_match(/#{REGEXP_BOLD}#{REGEXP_MAGENTA} \(0.0ms\)#{REGEXP_CLEAR}/i, logger.debugs.last)
+      logger.sql(Event.new(0.9, sql: verb.to_s))
+      assert_match(/#{REGEXP_BOLD}#{REGEXP_MAGENTA} \(0\.9ms\)#{REGEXP_CLEAR}/i, logger.debugs.last)
 
-      logger.sql(event.new(0, {sql: verb.to_s, name: "SQL"}))
-      assert_match(/#{REGEXP_BOLD}#{REGEXP_MAGENTA}SQL \(0.0ms\)#{REGEXP_CLEAR}/i, logger.debugs.last)
+      logger.sql(Event.new(0.9, sql: verb.to_s, name: "SQL"))
+      assert_match(/#{REGEXP_BOLD}#{REGEXP_MAGENTA}SQL \(0\.9ms\)#{REGEXP_CLEAR}/i, logger.debugs.last)
     end
   end
 
   def test_basic_payload_name_logging_coloration_named_sql
-    event = Struct.new(:duration, :payload)
     logger = TestDebugLogSubscriber.new
     logger.colorize_logging = true
     SQL_COLORINGS.each do |verb, _|
-      logger.sql(event.new(0, {sql: verb.to_s, name: "Model Load"}))
-      assert_match(/#{REGEXP_BOLD}#{REGEXP_CYAN}Model Load \(0.0ms\)#{REGEXP_CLEAR}/i, logger.debugs.last)
+      logger.sql(Event.new(0.9, sql: verb.to_s, name: "Model Load"))
+      assert_match(/#{REGEXP_BOLD}#{REGEXP_CYAN}Model Load \(0\.9ms\)#{REGEXP_CLEAR}/i, logger.debugs.last)
 
-      logger.sql(event.new(0, {sql: verb.to_s, name: "Model Exists"}))
-      assert_match(/#{REGEXP_BOLD}#{REGEXP_CYAN}Model Exists \(0.0ms\)#{REGEXP_CLEAR}/i, logger.debugs.last)
+      logger.sql(Event.new(0.9, sql: verb.to_s, name: "Model Exists"))
+      assert_match(/#{REGEXP_BOLD}#{REGEXP_CYAN}Model Exists \(0\.9ms\)#{REGEXP_CLEAR}/i, logger.debugs.last)
 
-      logger.sql(event.new(0, {sql: verb.to_s, name: "ANY SPECIFIC NAME"}))
-      assert_match(/#{REGEXP_BOLD}#{REGEXP_CYAN}ANY SPECIFIC NAME \(0.0ms\)#{REGEXP_CLEAR}/i, logger.debugs.last)
+      logger.sql(Event.new(0.9, sql: verb.to_s, name: "ANY SPECIFIC NAME"))
+      assert_match(/#{REGEXP_BOLD}#{REGEXP_CYAN}ANY SPECIFIC NAME \(0\.9ms\)#{REGEXP_CLEAR}/i, logger.debugs.last)
     end
   end
 
   def test_query_logging_coloration_with_nested_select
-    event = Struct.new(:duration, :payload)
     logger = TestDebugLogSubscriber.new
     logger.colorize_logging = true
     SQL_COLORINGS.slice(:SELECT, :INSERT, :UPDATE, :DELETE).each do |verb, color_regex|
-      logger.sql(event.new(0, sql: "#{verb} WHERE ID IN SELECT"))
-      assert_match(/#{REGEXP_BOLD}#{REGEXP_MAGENTA} \(0.0ms\)#{REGEXP_CLEAR}  #{REGEXP_BOLD}#{color_regex}#{verb} WHERE ID IN SELECT#{REGEXP_CLEAR}/i, logger.debugs.last)
+      logger.sql(Event.new(0.9, sql: "#{verb} WHERE ID IN SELECT"))
+      assert_match(/#{REGEXP_BOLD}#{REGEXP_MAGENTA} \(0\.9ms\)#{REGEXP_CLEAR}  #{REGEXP_BOLD}#{color_regex}#{verb} WHERE ID IN SELECT#{REGEXP_CLEAR}/i, logger.debugs.last)
     end
   end
 
   def test_query_logging_coloration_with_multi_line_nested_select
-    event = Struct.new(:duration, :payload)
     logger = TestDebugLogSubscriber.new
     logger.colorize_logging = true
     SQL_COLORINGS.slice(:SELECT, :INSERT, :UPDATE, :DELETE).each do |verb, color_regex|
@@ -145,13 +141,12 @@ class LogSubscriberTest < ActiveRecord::TestCase
           SELECT ID FROM THINGS
         )
       EOS
-      logger.sql(event.new(0, sql: sql))
-      assert_match(/#{REGEXP_BOLD}#{REGEXP_MAGENTA} \(0.0ms\)#{REGEXP_CLEAR}  #{REGEXP_BOLD}#{color_regex}.*#{verb}.*#{REGEXP_CLEAR}/mi, logger.debugs.last)
+      logger.sql(Event.new(0.9, sql: sql))
+      assert_match(/#{REGEXP_BOLD}#{REGEXP_MAGENTA} \(0\.9ms\)#{REGEXP_CLEAR}  #{REGEXP_BOLD}#{color_regex}.*#{verb}.*#{REGEXP_CLEAR}/mi, logger.debugs.last)
     end
   end
 
   def test_query_logging_coloration_with_lock
-    event = Struct.new(:duration, :payload)
     logger = TestDebugLogSubscriber.new
     logger.colorize_logging = true
     sql = <<-EOS
@@ -159,14 +154,14 @@ class LogSubscriberTest < ActiveRecord::TestCase
         (SELECT * FROM mytable FOR UPDATE) ss
       WHERE col1 = 5;
     EOS
-    logger.sql(event.new(0, sql: sql))
-    assert_match(/#{REGEXP_BOLD}#{REGEXP_MAGENTA} \(0.0ms\)#{REGEXP_CLEAR}  #{REGEXP_BOLD}#{SQL_COLORINGS[:LOCK]}.*FOR UPDATE.*#{REGEXP_CLEAR}/mi, logger.debugs.last)
+    logger.sql(Event.new(0.9, sql: sql))
+    assert_match(/#{REGEXP_BOLD}#{REGEXP_MAGENTA} \(0\.9ms\)#{REGEXP_CLEAR}  #{REGEXP_BOLD}#{SQL_COLORINGS[:LOCK]}.*FOR UPDATE.*#{REGEXP_CLEAR}/mi, logger.debugs.last)
 
     sql = <<-EOS
       LOCK TABLE films IN SHARE MODE;
     EOS
-    logger.sql(event.new(0, sql: sql))
-    assert_match(/#{REGEXP_BOLD}#{REGEXP_MAGENTA} \(0.0ms\)#{REGEXP_CLEAR}  #{REGEXP_BOLD}#{SQL_COLORINGS[:LOCK]}.*LOCK TABLE.*#{REGEXP_CLEAR}/mi, logger.debugs.last)
+    logger.sql(Event.new(0.9, sql: sql))
+    assert_match(/#{REGEXP_BOLD}#{REGEXP_MAGENTA} \(0\.9ms\)#{REGEXP_CLEAR}  #{REGEXP_BOLD}#{SQL_COLORINGS[:LOCK]}.*LOCK TABLE.*#{REGEXP_CLEAR}/mi, logger.debugs.last)
   end
 
   def test_exists_query_logging
@@ -177,6 +172,22 @@ class LogSubscriberTest < ActiveRecord::TestCase
     assert_match(/SELECT .*?FROM .?developers.?/i, @logger.logged(:debug).last)
   end
 
+  def test_vebose_query_logs
+    ActiveRecord::Base.verbose_query_logs = true
+
+    logger = TestDebugLogSubscriber.new
+    logger.sql(Event.new(0, sql: "hi mom!"))
+    assert_match(/↳/, @logger.logged(:debug).last)
+  ensure
+    ActiveRecord::Base.verbose_query_logs = false
+  end
+
+  def test_verbose_query_logs_disabled_by_default
+    logger = TestDebugLogSubscriber.new
+    logger.sql(Event.new(0, sql: "hi mom!"))
+    assert_no_match(/↳/, @logger.logged(:debug).last)
+  end
+
   def test_cached_queries
     ActiveRecord::Base.cache do
       Developer.all.load
@@ -211,7 +222,7 @@ class LogSubscriberTest < ActiveRecord::TestCase
 
   if ActiveRecord::Base.connection.prepared_statements
     def test_binary_data_is_not_logged
-      Binary.create(data: 'some binary data')
+      Binary.create(data: "some binary data")
       wait
       assert_match(/<16 bytes of binary data>/, @logger.logged(:debug).join)
     end
diff --git a/activerecord/test/cases/migration/change_schema_test.rb b/activerecord/test/cases/migration/change_schema_test.rb
index d6963b48d7..38a906c8f5 100644
--- a/activerecord/test/cases/migration/change_schema_test.rb
+++ b/activerecord/test/cases/migration/change_schema_test.rb
@@ -1,4 +1,6 @@
-require 'cases/helper'
+# frozen_string_literal: true
+
+require "cases/helper"
 
 module ActiveRecord
   class Migration
@@ -40,10 +42,10 @@ module ActiveRecord
 
       def test_create_table_with_not_null_column
         connection.create_table :testings do |t|
-          t.column :foo, :string, :null => false
+          t.column :foo, :string, null: false
         end
 
-        assert_raises(ActiveRecord::StatementInvalid) do
+        assert_raises(ActiveRecord::NotNullViolation) do
           connection.execute "insert into testings (foo) values (NULL)"
         end
       end
@@ -53,11 +55,11 @@ module ActiveRecord
         mysql = current_adapter?(:Mysql2Adapter)
 
         connection.create_table :testings do |t|
-          t.column :one, :string, :default => "hello"
-          t.column :two, :boolean, :default => true
-          t.column :three, :boolean, :default => false
-          t.column :four, :integer, :default => 1
-          t.column :five, :text, :default => "hello" unless mysql
+          t.column :one, :string, default: "hello"
+          t.column :two, :boolean, default: true
+          t.column :three, :boolean, default: false
+          t.column :four, :integer, default: 1
+          t.column :five, :text, default: "hello" unless mysql
         end
 
         columns = connection.columns(:testings)
@@ -70,14 +72,14 @@ module ActiveRecord
         assert_equal "hello", one.default
         assert_equal true, connection.lookup_cast_type_from_column(two).deserialize(two.default)
         assert_equal false, connection.lookup_cast_type_from_column(three).deserialize(three.default)
-        assert_equal '1', four.default
+        assert_equal "1", four.default
         assert_equal "hello", five.default unless mysql
       end
 
       if current_adapter?(:PostgreSQLAdapter)
         def test_add_column_with_array
           connection.create_table :testings
-          connection.add_column :testings, :foo, :string, :array => true
+          connection.add_column :testings, :foo, :string, array: true
 
           columns = connection.columns(:testings)
           array_column = columns.detect { |c| c.name == "foo" }
@@ -87,7 +89,7 @@ module ActiveRecord
 
         def test_create_table_with_array_column
           connection.create_table :testings do |t|
-            t.string :foo, :array => true
+            t.string :foo, array: true
           end
 
           columns = connection.columns(:testings)
@@ -105,9 +107,9 @@ module ActiveRecord
         eight   = columns.detect { |c| c.name == "eight_int"   }
 
         if current_adapter?(:OracleAdapter)
-          assert_equal 'NUMBER(19)', eight.sql_type
+          assert_equal "NUMBER(19)", eight.sql_type
         elsif current_adapter?(:SQLite3Adapter)
-          assert_equal 'bigint', eight.sql_type
+          assert_equal "bigint", eight.sql_type
         else
           assert_equal :integer, eight.type
           assert_equal 8, eight.limit
@@ -118,13 +120,13 @@ module ActiveRecord
 
       def test_create_table_with_limits
         connection.create_table :testings do |t|
-          t.column :foo, :string, :limit => 255
+          t.column :foo, :string, limit: 255
 
           t.column :default_int, :integer
 
-          t.column :one_int,    :integer, :limit => 1
-          t.column :four_int,   :integer, :limit => 4
-          t.column :eight_int,  :integer, :limit => 8
+          t.column :one_int,    :integer, limit: 1
+          t.column :four_int,   :integer, limit: 4
+          t.column :eight_int,  :integer, limit: 8
         end
 
         columns = connection.columns(:testings)
@@ -137,20 +139,20 @@ module ActiveRecord
         eight   = columns.detect { |c| c.name == "eight_int"   }
 
         if current_adapter?(:PostgreSQLAdapter)
-          assert_equal 'integer', default.sql_type
-          assert_equal 'smallint', one.sql_type
-          assert_equal 'integer', four.sql_type
-          assert_equal 'bigint', eight.sql_type
+          assert_equal "integer", default.sql_type
+          assert_equal "smallint", one.sql_type
+          assert_equal "integer", four.sql_type
+          assert_equal "bigint", eight.sql_type
         elsif current_adapter?(:Mysql2Adapter)
-          assert_match 'int(11)', default.sql_type
-          assert_match 'tinyint', one.sql_type
-          assert_match 'int', four.sql_type
-          assert_match 'bigint', eight.sql_type
+          assert_match "int(11)", default.sql_type
+          assert_match "tinyint", one.sql_type
+          assert_match "int", four.sql_type
+          assert_match "bigint", eight.sql_type
         elsif current_adapter?(:OracleAdapter)
-          assert_equal 'NUMBER(38)', default.sql_type
-          assert_equal 'NUMBER(1)', one.sql_type
-          assert_equal 'NUMBER(4)', four.sql_type
-          assert_equal 'NUMBER(8)', eight.sql_type
+          assert_equal "NUMBER(38)", default.sql_type
+          assert_equal "NUMBER(1)", one.sql_type
+          assert_equal "NUMBER(4)", four.sql_type
+          assert_equal "NUMBER(8)", eight.sql_type
         end
       end
 
@@ -200,8 +202,8 @@ module ActiveRecord
         end
         created_columns = connection.columns(table_name)
 
-        created_at_column = created_columns.detect {|c| c.name == 'created_at' }
-        updated_at_column = created_columns.detect {|c| c.name == 'updated_at' }
+        created_at_column = created_columns.detect { |c| c.name == "created_at" }
+        updated_at_column = created_columns.detect { |c| c.name == "updated_at" }
 
         assert !created_at_column.null
         assert !updated_at_column.null
@@ -213,8 +215,8 @@ module ActiveRecord
         end
         created_columns = connection.columns(table_name)
 
-        created_at_column = created_columns.detect {|c| c.name == 'created_at' }
-        updated_at_column = created_columns.detect {|c| c.name == 'updated_at' }
+        created_at_column = created_columns.detect { |c| c.name == "created_at" }
+        updated_at_column = created_columns.detect { |c| c.name == "updated_at" }
 
         assert created_at_column.null
         assert updated_at_column.null
@@ -231,9 +233,9 @@ module ActiveRecord
           connection.create_table :testings do |t|
             t.column :foo, :string
           end
-          connection.add_column :testings, :bar, :string, :null => false
+          connection.add_column :testings, :bar, :string, null: false
 
-          assert_raise(ActiveRecord::StatementInvalid) do
+          assert_raise(ActiveRecord::NotNullViolation) do
             connection.execute "insert into testings (foo, bar) values ('hello', NULL)"
           end
         end
@@ -244,12 +246,16 @@ module ActiveRecord
           t.column :foo, :string
         end
 
-        con = connection
-        connection.execute "insert into testings (#{con.quote_column_name('id')}, #{con.quote_column_name('foo')}) values (1, 'hello')"
-        assert_nothing_raised {connection.add_column :testings, :bar, :string, :null => false, :default => "default" }
+        quoted_id  = connection.quote_column_name("id")
+        quoted_foo = connection.quote_column_name("foo")
+        quoted_bar = connection.quote_column_name("bar")
+        connection.execute("insert into testings (#{quoted_id}, #{quoted_foo}) values (1, 'hello')")
+        assert_nothing_raised do
+          connection.add_column :testings, :bar, :string, null: false, default: "default"
+        end
 
-        assert_raises(ActiveRecord::StatementInvalid) do
-          connection.execute "insert into testings (#{con.quote_column_name('id')}, #{con.quote_column_name('foo')}, #{con.quote_column_name('bar')}) values (2, 'hello', NULL)"
+        assert_raises(ActiveRecord::NotNullViolation) do
+          connection.execute("insert into testings (#{quoted_id}, #{quoted_foo}, #{quoted_bar}) values (2, 'hello', NULL)")
         end
       end
 
@@ -258,15 +264,18 @@ module ActiveRecord
           t.column :foo, :timestamp
         end
 
-        klass = Class.new(ActiveRecord::Base)
-        klass.table_name = 'testings'
+        column = connection.columns(:testings).find { |c| c.name == "foo" }
 
-        assert_equal :datetime, klass.columns_hash['foo'].type
+        assert_equal :datetime, column.type
 
         if current_adapter?(:PostgreSQLAdapter)
-          assert_equal 'timestamp without time zone', klass.columns_hash['foo'].sql_type
+          assert_equal "timestamp without time zone", column.sql_type
+        elsif current_adapter?(:Mysql2Adapter)
+          assert_equal "timestamp", column.sql_type
+        elsif current_adapter?(:OracleAdapter)
+          assert_equal "TIMESTAMP(6)", column.sql_type
         else
-          assert_equal klass.connection.type_to_sql('datetime'), klass.columns_hash['foo'].sql_type
+          assert_equal connection.type_to_sql("datetime"), column.sql_type
         end
       end
 
@@ -275,7 +284,7 @@ module ActiveRecord
           t.column :select, :string
         end
 
-        connection.change_column :testings, :select, :string, :limit => 10
+        connection.change_column :testings, :select, :string, limit: 10
 
         # Oracle needs primary key value from sequence
         if current_adapter?(:OracleAdapter)
@@ -290,17 +299,17 @@ module ActiveRecord
           t.column :title, :string
         end
         person_klass = Class.new(ActiveRecord::Base)
-        person_klass.table_name = 'testings'
+        person_klass.table_name = "testings"
 
-        person_klass.connection.add_column "testings", "wealth", :integer, :null => false, :default => 99
+        person_klass.connection.add_column "testings", "wealth", :integer, null: false, default: 99
         person_klass.reset_column_information
         assert_equal 99, person_klass.column_defaults["wealth"]
         assert_equal false, person_klass.columns_hash["wealth"].null
         # Oracle needs primary key value from sequence
         if current_adapter?(:OracleAdapter)
-          assert_nothing_raised {person_klass.connection.execute("insert into testings (id, title) values (testings_seq.nextval, 'tester')")}
+          assert_nothing_raised { person_klass.connection.execute("insert into testings (id, title) values (testings_seq.nextval, 'tester')") }
         else
-          assert_nothing_raised {person_klass.connection.execute("insert into testings (title) values ('tester')")}
+          assert_nothing_raised { person_klass.connection.execute("insert into testings (title) values ('tester')") }
         end
 
         # change column default to see that column doesn't lose its not null definition
@@ -317,19 +326,19 @@ module ActiveRecord
         assert_equal false, person_klass.columns_hash["money"].null
 
         # change column
-        person_klass.connection.change_column "testings", "money", :integer, :null => false, :default => 1000
+        person_klass.connection.change_column "testings", "money", :integer, null: false, default: 1000
         person_klass.reset_column_information
         assert_equal 1000, person_klass.column_defaults["money"]
         assert_equal false, person_klass.columns_hash["money"].null
 
         # change column, make it nullable and clear default
-        person_klass.connection.change_column "testings", "money", :integer, :null => true, :default => nil
+        person_klass.connection.change_column "testings", "money", :integer, null: true, default: nil
         person_klass.reset_column_information
         assert_nil person_klass.columns_hash["money"].default
         assert_equal true, person_klass.columns_hash["money"].null
 
         # change_column_null, make it not nullable and set null values to a default value
-        person_klass.connection.execute('UPDATE testings SET money = NULL')
+        person_klass.connection.execute("UPDATE testings SET money = NULL")
         person_klass.connection.change_column_null "testings", "money", false, 2000
         person_klass.reset_column_information
         assert_nil person_klass.columns_hash["money"].default
@@ -346,9 +355,9 @@ module ActiveRecord
           end
           notnull_migration.new.suppress_messages do
             notnull_migration.migrate(:up)
-            assert_equal false, connection.columns(:testings).find{ |c| c.name == "foo"}.null
+            assert_equal false, connection.columns(:testings).find { |c| c.name == "foo" }.null
             notnull_migration.migrate(:down)
-            assert connection.columns(:testings).find{ |c| c.name == "foo"}.null
+            assert connection.columns(:testings).find { |c| c.name == "foo" }.null
           end
         end
       end
@@ -365,7 +374,7 @@ module ActiveRecord
       def test_column_exists_with_type
         connection.create_table :testings do |t|
           t.column :foo, :string
-          t.column :bar, :decimal, :precision => 8, :scale => 2
+          t.column :bar, :decimal, precision: 8, scale: 2
         end
 
         assert connection.column_exists?(:testings, :foo, :string)
@@ -380,7 +389,7 @@ module ActiveRecord
           t.column :foo, :string, limit: 100
           t.column :bar, :decimal, precision: 8, scale: 2
           t.column :taggable_id, :integer, null: false
-          t.column :taggable_type, :string, default: 'Photo'
+          t.column :taggable_type, :string, default: "Photo"
         end
 
         assert connection.column_exists?(:testings, :foo, :string, limit: 100)
@@ -389,7 +398,7 @@ module ActiveRecord
         assert_not connection.column_exists?(:testings, :bar, :decimal, precision: nil, scale: nil)
         assert connection.column_exists?(:testings, :taggable_id, :integer, null: false)
         assert_not connection.column_exists?(:testings, :taggable_id, :integer, null: true)
-        assert connection.column_exists?(:testings, :taggable_type, :string, default: 'Photo')
+        assert connection.column_exists?(:testings, :taggable_type, :string, default: "Photo")
         assert_not connection.column_exists?(:testings, :taggable_type, :string, default: nil)
       end
 
@@ -405,9 +414,9 @@ module ActiveRecord
 
       def test_drop_table_if_exists
         connection.create_table(:testings)
-        ActiveSupport::Deprecation.silence { assert connection.table_exists?(:testings) }
+        assert connection.table_exists?(:testings)
         connection.drop_table(:testings, if_exists: true)
-        ActiveSupport::Deprecation.silence { assert_not connection.table_exists?(:testings) }
+        assert_not connection.table_exists?(:testings)
       end
 
       def test_drop_table_if_exists_nothing_raised
@@ -415,13 +424,13 @@ module ActiveRecord
       end
 
       private
-      def testing_table_with_only_foo_attribute
-        connection.create_table :testings, :id => false do |t|
-          t.column :foo, :string
-        end
+        def testing_table_with_only_foo_attribute
+          connection.create_table :testings, id: false do |t|
+            t.column :foo, :string
+          end
 
-        yield
-      end
+          yield
+        end
     end
 
     if ActiveRecord::Base.connection.supports_foreign_keys?
diff --git a/activerecord/test/cases/migration/change_table_test.rb b/activerecord/test/cases/migration/change_table_test.rb
index 2f9c50141f..034bf32165 100644
--- a/activerecord/test/cases/migration/change_table_test.rb
+++ b/activerecord/test/cases/migration/change_table_test.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require "cases/migration/helper"
 
 module ActiveRecord
@@ -95,7 +97,7 @@ module ActiveRecord
       def test_remove_timestamps_creates_updated_at_and_created_at
         with_change_table do |t|
           @connection.expect :remove_timestamps, nil, [:delete_me, { null: true }]
-          t.remove_timestamps({ null: true })
+          t.remove_timestamps(null: true)
         end
       end
 
@@ -157,8 +159,8 @@ module ActiveRecord
 
       def test_column_creates_column_with_options
         with_change_table do |t|
-          @connection.expect :add_column, nil, [:delete_me, :bar, :integer, {:null => false}]
-          t.column :bar, :integer, :null => false
+          @connection.expect :add_column, nil, [:delete_me, :bar, :integer, { null: false }]
+          t.column :bar, :integer, null: false
         end
       end
 
@@ -171,8 +173,8 @@ module ActiveRecord
 
       def test_index_creates_index_with_options
         with_change_table do |t|
-          @connection.expect :add_index, nil, [:delete_me, :bar, {:unique => true}]
-          t.index :bar, :unique => true
+          @connection.expect :add_index, nil, [:delete_me, :bar, { unique: true }]
+          t.index :bar, unique: true
         end
       end
 
@@ -185,8 +187,8 @@ module ActiveRecord
 
       def test_index_exists_with_options
         with_change_table do |t|
-          @connection.expect :index_exists?, nil, [:delete_me, :bar, {:unique => true}]
-          t.index_exists?(:bar, :unique => true)
+          @connection.expect :index_exists?, nil, [:delete_me, :bar, { unique: true }]
+          t.index_exists?(:bar, unique: true)
         end
       end
 
@@ -206,8 +208,8 @@ module ActiveRecord
 
       def test_change_changes_column_with_options
         with_change_table do |t|
-          @connection.expect :change_column, nil, [:delete_me, :bar, :string, {:null => true}]
-          t.change :bar, :string, :null => true
+          @connection.expect :change_column, nil, [:delete_me, :bar, :string, { null: true }]
+          t.change :bar, :string, null: true
         end
       end
 
@@ -234,8 +236,8 @@ module ActiveRecord
 
       def test_remove_index_removes_index_with_options
         with_change_table do |t|
-          @connection.expect :remove_index, nil, [:delete_me, {:unique => true}]
-          t.remove_index :unique => true
+          @connection.expect :remove_index, nil, [:delete_me, { unique: true }]
+          t.remove_index unique: true
         end
       end
 
diff --git a/activerecord/test/cases/migration/column_attributes_test.rb b/activerecord/test/cases/migration/column_attributes_test.rb
index 29546525f3..3022121f4c 100644
--- a/activerecord/test/cases/migration/column_attributes_test.rb
+++ b/activerecord/test/cases/migration/column_attributes_test.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require "cases/migration/helper"
 
 module ActiveRecord
@@ -9,7 +11,7 @@ module ActiveRecord
 
       def test_add_column_newline_default
         string = "foo\nbar"
-        add_column 'test_models', 'command', :string, :default => string
+        add_column "test_models", "command", :string, default: string
         TestModel.reset_column_information
 
         assert_equal string, TestModel.new.command
@@ -18,10 +20,10 @@ module ActiveRecord
       def test_add_remove_single_field_using_string_arguments
         assert_no_column TestModel, :last_name
 
-        add_column 'test_models', 'last_name', :string
+        add_column "test_models", "last_name", :string
         assert_column TestModel, :last_name
 
-        remove_column 'test_models', 'last_name'
+        remove_column "test_models", "last_name"
         assert_no_column TestModel, :last_name
       end
 
@@ -43,11 +45,11 @@ module ActiveRecord
         assert_nil TestModel.columns_hash["description"].limit
       end
 
-      if current_adapter?(:Mysql2Adapter)
+      if current_adapter?(:Mysql2Adapter, :PostgreSQLAdapter)
         def test_unabstracted_database_dependent_types
-          add_column :test_models, :intelligence_quotient, :tinyint
+          add_column :test_models, :intelligence_quotient, :smallint
           TestModel.reset_column_information
-          assert_match(/tinyint/, TestModel.columns_hash['intelligence_quotient'].sql_type)
+          assert_match(/smallint/, TestModel.columns_hash["intelligence_quotient"].sql_type)
         end
       end
 
@@ -56,15 +58,13 @@ module ActiveRecord
         # functionality. This allows us to more easily catch INSERT being broken,
         # but SELECT actually working fine.
         def test_native_decimal_insert_manual_vs_automatic
-          correct_value = '0012345678901234567890.0123456789'.to_d
+          correct_value = "0012345678901234567890.0123456789".to_d
 
-          connection.add_column "test_models", "wealth", :decimal, :precision => '30', :scale => '10'
+          connection.add_column "test_models", "wealth", :decimal, precision: "30", scale: "10"
 
           # Do a manual insertion
           if current_adapter?(:OracleAdapter)
             connection.execute "insert into test_models (id, wealth) values (people_seq.nextval, 12345678901234567890.0123456789)"
-          elsif current_adapter?(:PostgreSQLAdapter)
-            connection.execute "insert into test_models (wealth) values (12345678901234567890.0123456789)"
           else
             connection.execute "insert into test_models (wealth) values (12345678901234567890.0123456789)"
           end
@@ -74,15 +74,13 @@ module ActiveRecord
           assert_kind_of BigDecimal, row.wealth
 
           # If this assert fails, that means the SELECT is broken!
-          unless current_adapter?(:SQLite3Adapter)
-            assert_equal correct_value, row.wealth
-          end
+          assert_equal correct_value, row.wealth
 
           # Reset to old state
           TestModel.delete_all
 
           # Now use the Rails insertion
-          TestModel.create :wealth => BigDecimal.new("12345678901234567890.0123456789")
+          TestModel.create wealth: BigDecimal("12345678901234567890.0123456789")
 
           # SELECT
           row = TestModel.first
@@ -94,26 +92,40 @@ module ActiveRecord
       end
 
       def test_add_column_with_precision_and_scale
-        connection.add_column 'test_models', 'wealth', :decimal, :precision => 9, :scale => 7
+        connection.add_column "test_models", "wealth", :decimal, precision: 9, scale: 7
 
-        wealth_column = TestModel.columns_hash['wealth']
+        wealth_column = TestModel.columns_hash["wealth"]
         assert_equal 9, wealth_column.precision
         assert_equal 7, wealth_column.scale
       end
 
+      # Test SQLite3 adapter specifically for decimal types with precision and scale
+      # attributes, since these need to be maintained in schema but aren't actually
+      # used in SQLite3 itself
       if current_adapter?(:SQLite3Adapter)
+        def test_change_column_with_new_precision_and_scale
+          connection.add_column "test_models", "wealth", :decimal, precision: 9, scale: 7
+
+          connection.change_column "test_models", "wealth", :decimal, precision: 12, scale: 8
+          TestModel.reset_column_information
+
+          wealth_column = TestModel.columns_hash["wealth"]
+          assert_equal 12, wealth_column.precision
+          assert_equal 8, wealth_column.scale
+        end
+
         def test_change_column_preserve_other_column_precision_and_scale
-          connection.add_column 'test_models', 'last_name', :string
-          connection.add_column 'test_models', 'wealth', :decimal, :precision => 9, :scale => 7
+          connection.add_column "test_models", "last_name", :string
+          connection.add_column "test_models", "wealth", :decimal, precision: 9, scale: 7
 
-          wealth_column = TestModel.columns_hash['wealth']
+          wealth_column = TestModel.columns_hash["wealth"]
           assert_equal 9, wealth_column.precision
           assert_equal 7, wealth_column.scale
 
-          connection.change_column 'test_models', 'last_name', :string, :null => false
+          connection.change_column "test_models", "last_name", :string, null: false
           TestModel.reset_column_information
 
-          wealth_column = TestModel.columns_hash['wealth']
+          wealth_column = TestModel.columns_hash["wealth"]
           assert_equal 9, wealth_column.precision
           assert_equal 7, wealth_column.scale
         end
@@ -126,28 +138,28 @@ module ActiveRecord
           add_column "test_models", "bio", :text
           add_column "test_models", "age", :integer
           add_column "test_models", "height", :float
-          add_column "test_models", "wealth", :decimal, :precision => '30', :scale => '10'
+          add_column "test_models", "wealth", :decimal, precision: "30", scale: "10"
           add_column "test_models", "birthday", :datetime
           add_column "test_models", "favorite_day", :date
           add_column "test_models", "moment_of_truth", :datetime
           add_column "test_models", "male", :boolean
 
-          TestModel.create :first_name => 'bob', :last_name => 'bobsen',
-            :bio => "I was born ....", :age => 18, :height => 1.78,
-            :wealth => BigDecimal.new("12345678901234567890.0123456789"),
-            :birthday => 18.years.ago, :favorite_day => 10.days.ago,
-            :moment_of_truth => "1782-10-10 21:40:18", :male => true
+          TestModel.create first_name: "bob", last_name: "bobsen",
+            bio: "I was born ....", age: 18, height: 1.78,
+            wealth: BigDecimal("12345678901234567890.0123456789"),
+            birthday: 18.years.ago, favorite_day: 10.days.ago,
+            moment_of_truth: "1782-10-10 21:40:18", male: true
 
           bob = TestModel.first
-          assert_equal 'bob', bob.first_name
-          assert_equal 'bobsen', bob.last_name
+          assert_equal "bob", bob.first_name
+          assert_equal "bobsen", bob.last_name
           assert_equal "I was born ....", bob.bio
           assert_equal 18, bob.age
 
           # Test for 30 significant digits (beyond the 16 of float), 10 of them
           # after the decimal place.
 
-          assert_equal BigDecimal.new("0012345678901234567890.0123456789"), bob.wealth
+          assert_equal BigDecimal("0012345678901234567890.0123456789"), bob.wealth
 
           assert_equal true, bob.male?
 
@@ -156,14 +168,7 @@ module ActiveRecord
           assert_equal String, bob.bio.class
           assert_kind_of Integer, bob.age
           assert_equal Time, bob.birthday.class
-
-          if current_adapter?(:OracleAdapter)
-            # Oracle doesn't differentiate between date/time
-            assert_equal Time, bob.favorite_day.class
-          else
-            assert_equal Date, bob.favorite_day.class
-          end
-
+          assert_equal Date, bob.favorite_day.class
           assert_instance_of TrueClass, bob.male?
           assert_kind_of BigDecimal, bob.wealth
         end
@@ -171,10 +176,10 @@ module ActiveRecord
 
       if current_adapter?(:Mysql2Adapter, :PostgreSQLAdapter)
         def test_out_of_range_limit_should_raise
-          assert_raise(ActiveRecordError) { add_column :test_models, :integer_too_big, :integer, :limit => 10 }
+          assert_raise(ActiveRecordError) { add_column :test_models, :integer_too_big, :integer, limit: 10 }
 
           unless current_adapter?(:PostgreSQLAdapter)
-            assert_raise(ActiveRecordError) { add_column :test_models, :text_too_big, :integer, :limit => 0xfffffffff }
+            assert_raise(ActiveRecordError) { add_column :test_models, :text_too_big, :text, limit: 0xfffffffff }
           end
         end
       end
diff --git a/activerecord/test/cases/migration/column_positioning_test.rb b/activerecord/test/cases/migration/column_positioning_test.rb
index 8294da0373..1c62a68cf9 100644
--- a/activerecord/test/cases/migration/column_positioning_test.rb
+++ b/activerecord/test/cases/migration/column_positioning_test.rb
@@ -1,4 +1,6 @@
-require 'cases/helper'
+# frozen_string_literal: true
+
+require "cases/helper"
 
 module ActiveRecord
   class Migration
@@ -11,7 +13,7 @@ module ActiveRecord
 
         @connection = ActiveRecord::Base.connection
 
-        connection.create_table :testings, :id => false do |t|
+        connection.create_table :testings, id: false do |t|
           t.column :first, :integer
           t.column :second, :integer
           t.column :third, :integer
@@ -34,22 +36,32 @@ module ActiveRecord
         end
 
         def test_add_column_with_positioning_first
-          conn.add_column :testings, :new_col, :integer, :first => true
+          conn.add_column :testings, :new_col, :integer, first: true
           assert_equal %w(new_col first second third), conn.columns(:testings).map(&:name)
         end
 
         def test_add_column_with_positioning_after
-          conn.add_column :testings, :new_col, :integer, :after => :first
+          conn.add_column :testings, :new_col, :integer, after: :first
           assert_equal %w(first new_col second third), conn.columns(:testings).map(&:name)
         end
 
         def test_change_column_with_positioning
-          conn.change_column :testings, :second, :integer, :first => true
+          conn.change_column :testings, :second, :integer, first: true
           assert_equal %w(second first third), conn.columns(:testings).map(&:name)
 
-          conn.change_column :testings, :second, :integer, :after => :third
+          conn.change_column :testings, :second, :integer, after: :third
           assert_equal %w(first third second), conn.columns(:testings).map(&:name)
         end
+
+        def test_add_reference_with_positioning_first
+          conn.add_reference :testings, :new, polymorphic: true, first: true
+          assert_equal %w(new_id new_type first second third), conn.columns(:testings).map(&:name)
+        end
+
+        def test_add_reference_with_positioning_after
+          conn.add_reference :testings, :new, polymorphic: true, after: :first
+          assert_equal %w(first new_id new_type second third), conn.columns(:testings).map(&:name)
+        end
       end
     end
   end
diff --git a/activerecord/test/cases/migration/columns_test.rb b/activerecord/test/cases/migration/columns_test.rb
index fca1cb7e97..8ca20b6172 100644
--- a/activerecord/test/cases/migration/columns_test.rb
+++ b/activerecord/test/cases/migration/columns_test.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require "cases/migration/helper"
 
 module ActiveRecord
@@ -13,7 +15,7 @@ module ActiveRecord
         add_column "test_models", "girlfriend", :string
         TestModel.reset_column_information
 
-        TestModel.create :girlfriend => 'bobette'
+        TestModel.create girlfriend: "bobette"
 
         rename_column "test_models", "girlfriend", "exgirlfriend"
 
@@ -28,12 +30,12 @@ module ActiveRecord
       def test_rename_column_using_symbol_arguments
         add_column :test_models, :first_name, :string
 
-        TestModel.create :first_name => 'foo'
+        TestModel.create first_name: "foo"
 
         rename_column :test_models, :first_name, :nick_name
         TestModel.reset_column_information
-        assert TestModel.column_names.include?("nick_name")
-        assert_equal ['foo'], TestModel.all.map(&:nick_name)
+        assert_includes TestModel.column_names, "nick_name"
+        assert_equal ["foo"], TestModel.all.map(&:nick_name)
       end
 
       # FIXME: another integration test.  We should decouple this from the
@@ -41,25 +43,25 @@ module ActiveRecord
       def test_rename_column
         add_column "test_models", "first_name", "string"
 
-        TestModel.create :first_name => 'foo'
+        TestModel.create first_name: "foo"
 
         rename_column "test_models", "first_name", "nick_name"
         TestModel.reset_column_information
-        assert TestModel.column_names.include?("nick_name")
-        assert_equal ['foo'], TestModel.all.map(&:nick_name)
+        assert_includes TestModel.column_names, "nick_name"
+        assert_equal ["foo"], TestModel.all.map(&:nick_name)
       end
 
       def test_rename_column_preserves_default_value_not_null
-        add_column 'test_models', 'salary', :integer, :default => 70000
+        add_column "test_models", "salary", :integer, default: 70000
 
         default_before = connection.columns("test_models").find { |c| c.name == "salary" }.default
-        assert_equal '70000', default_before
+        assert_equal "70000", default_before
 
         rename_column "test_models", "salary", "annual_salary"
 
-        assert TestModel.column_names.include?("annual_salary")
+        assert_includes TestModel.column_names, "annual_salary"
         default_after = connection.columns("test_models").find { |c| c.name == "annual_salary" }.default
-        assert_equal '70000', default_after
+        assert_equal "70000", default_after
       end
 
       if current_adapter?(:Mysql2Adapter)
@@ -74,30 +76,31 @@ module ActiveRecord
 
       def test_rename_nonexistent_column
         exception = if current_adapter?(:PostgreSQLAdapter, :OracleAdapter)
-                      ActiveRecord::StatementInvalid
-                    else
-                      ActiveRecord::ActiveRecordError
-                    end
+          ActiveRecord::StatementInvalid
+        else
+          ActiveRecord::ActiveRecordError
+        end
+
         assert_raise(exception) do
           rename_column "test_models", "nonexistent", "should_fail"
         end
       end
 
       def test_rename_column_with_sql_reserved_word
-        add_column 'test_models', 'first_name', :string
+        add_column "test_models", "first_name", :string
         rename_column "test_models", "first_name", "group"
 
-        assert TestModel.column_names.include?("group")
+        assert_includes TestModel.column_names, "group"
       end
 
       def test_rename_column_with_an_index
         add_column "test_models", :hat_name, :string
         add_index :test_models, :hat_name
 
-        assert_equal 1, connection.indexes('test_models').size
+        assert_equal 1, connection.indexes("test_models").size
         rename_column "test_models", "hat_name", "name"
 
-        assert_equal ['index_test_models_on_name'], connection.indexes('test_models').map(&:name)
+        assert_equal ["index_test_models_on_name"], connection.indexes("test_models").map(&:name)
       end
 
       def test_rename_column_with_multi_column_index
@@ -105,153 +108,167 @@ module ActiveRecord
         add_column "test_models", :hat_style, :string, limit: 100
         add_index "test_models", ["hat_style", "hat_size"], unique: true
 
-        rename_column "test_models", "hat_size", 'size'
+        rename_column "test_models", "hat_size", "size"
         if current_adapter? :OracleAdapter
-          assert_equal ['i_test_models_hat_style_size'], connection.indexes('test_models').map(&:name)
+          assert_equal ["i_test_models_hat_style_size"], connection.indexes("test_models").map(&:name)
         else
-          assert_equal ['index_test_models_on_hat_style_and_size'], connection.indexes('test_models').map(&:name)
+          assert_equal ["index_test_models_on_hat_style_and_size"], connection.indexes("test_models").map(&:name)
         end
 
-        rename_column "test_models", "hat_style", 'style'
+        rename_column "test_models", "hat_style", "style"
         if current_adapter? :OracleAdapter
-          assert_equal ['i_test_models_style_size'], connection.indexes('test_models').map(&:name)
+          assert_equal ["i_test_models_style_size"], connection.indexes("test_models").map(&:name)
         else
-          assert_equal ['index_test_models_on_style_and_size'], connection.indexes('test_models').map(&:name)
+          assert_equal ["index_test_models_on_style_and_size"], connection.indexes("test_models").map(&:name)
         end
       end
 
       def test_rename_column_does_not_rename_custom_named_index
         add_column "test_models", :hat_name, :string
-        add_index :test_models, :hat_name, :name => 'idx_hat_name'
+        add_index :test_models, :hat_name, name: "idx_hat_name"
 
-        assert_equal 1, connection.indexes('test_models').size
+        assert_equal 1, connection.indexes("test_models").size
         rename_column "test_models", "hat_name", "name"
-        assert_equal ['idx_hat_name'], connection.indexes('test_models').map(&:name)
+        assert_equal ["idx_hat_name"], connection.indexes("test_models").map(&:name)
       end
 
       def test_remove_column_with_index
         add_column "test_models", :hat_name, :string
         add_index :test_models, :hat_name
 
-        assert_equal 1, connection.indexes('test_models').size
+        assert_equal 1, connection.indexes("test_models").size
         remove_column("test_models", "hat_name")
-        assert_equal 0, connection.indexes('test_models').size
+        assert_equal 0, connection.indexes("test_models").size
       end
 
       def test_remove_column_with_multi_column_index
+        # MariaDB starting with 10.2.8
+        # Dropping a column that is part of a multi-column UNIQUE constraint is not permitted.
+        skip if current_adapter?(:Mysql2Adapter) && connection.mariadb? && connection.version >= "10.2.8"
+
         add_column "test_models", :hat_size, :integer
-        add_column "test_models", :hat_style, :string, :limit => 100
-        add_index "test_models", ["hat_style", "hat_size"], :unique => true
+        add_column "test_models", :hat_style, :string, limit: 100
+        add_index "test_models", ["hat_style", "hat_size"], unique: true
 
-        assert_equal 1, connection.indexes('test_models').size
+        assert_equal 1, connection.indexes("test_models").size
         remove_column("test_models", "hat_size")
 
         # Every database and/or database adapter has their own behavior
         # if it drops the multi-column index when any of the indexed columns dropped by remove_column.
         if current_adapter?(:PostgreSQLAdapter, :OracleAdapter)
-          assert_equal [], connection.indexes('test_models').map(&:name)
+          assert_equal [], connection.indexes("test_models").map(&:name)
         else
-          assert_equal ['index_test_models_on_hat_style_and_hat_size'], connection.indexes('test_models').map(&:name)
+          assert_equal ["index_test_models_on_hat_style_and_hat_size"], connection.indexes("test_models").map(&:name)
         end
       end
 
       def test_change_type_of_not_null_column
-        change_column "test_models", "updated_at", :datetime, :null => false
-        change_column "test_models", "updated_at", :datetime, :null => false
+        change_column "test_models", "updated_at", :datetime, null: false
+        change_column "test_models", "updated_at", :datetime, null: false
 
         TestModel.reset_column_information
-        assert_equal false, TestModel.columns_hash['updated_at'].null
+        assert_equal false, TestModel.columns_hash["updated_at"].null
       ensure
-        change_column "test_models", "updated_at", :datetime, :null => true
+        change_column "test_models", "updated_at", :datetime, null: true
       end
 
       def test_change_column_nullability
         add_column "test_models", "funny", :boolean
         assert TestModel.columns_hash["funny"].null, "Column 'funny' must initially allow nulls"
 
-        change_column "test_models", "funny", :boolean, :null => false, :default => true
+        change_column "test_models", "funny", :boolean, null: false, default: true
 
         TestModel.reset_column_information
         assert_not TestModel.columns_hash["funny"].null, "Column 'funny' must *not* allow nulls at this point"
 
-        change_column "test_models", "funny", :boolean, :null => true
+        change_column "test_models", "funny", :boolean, null: true
         TestModel.reset_column_information
         assert TestModel.columns_hash["funny"].null, "Column 'funny' must allow nulls again at this point"
       end
 
       def test_change_column
-        add_column 'test_models', 'age', :integer
-        add_column 'test_models', 'approved', :boolean, :default => true
+        add_column "test_models", "age", :integer
+        add_column "test_models", "approved", :boolean, default: true
 
         old_columns = connection.columns(TestModel.table_name)
 
-        assert old_columns.find { |c| c.name == 'age' && c.type == :integer }
+        assert old_columns.find { |c| c.name == "age" && c.type == :integer }
 
         change_column "test_models", "age", :string
 
         new_columns = connection.columns(TestModel.table_name)
 
-        assert_not new_columns.find { |c| c.name == 'age' and c.type == :integer }
-        assert new_columns.find { |c| c.name == 'age' and c.type == :string }
+        assert_not new_columns.find { |c| c.name == "age" && c.type == :integer }
+        assert new_columns.find { |c| c.name == "age" && c.type == :string }
 
         old_columns = connection.columns(TestModel.table_name)
         assert old_columns.find { |c|
           default = connection.lookup_cast_type_from_column(c).deserialize(c.default)
-          c.name == 'approved' && c.type == :boolean && default == true
+          c.name == "approved" && c.type == :boolean && default == true
         }
 
-        change_column :test_models, :approved, :boolean, :default => false
+        change_column :test_models, :approved, :boolean, default: false
         new_columns = connection.columns(TestModel.table_name)
 
         assert_not new_columns.find { |c|
           default = connection.lookup_cast_type_from_column(c).deserialize(c.default)
-          c.name == 'approved' and c.type == :boolean and default == true
+          c.name == "approved" && c.type == :boolean && default == true
         }
         assert new_columns.find { |c|
           default = connection.lookup_cast_type_from_column(c).deserialize(c.default)
-          c.name == 'approved' and c.type == :boolean and default == false
+          c.name == "approved" && c.type == :boolean && default == false
         }
-        change_column :test_models, :approved, :boolean, :default => true
+        change_column :test_models, :approved, :boolean, default: true
       end
 
       def test_change_column_with_nil_default
-        add_column "test_models", "contributor", :boolean, :default => true
+        add_column "test_models", "contributor", :boolean, default: true
+        assert TestModel.new.contributor?
+
+        change_column "test_models", "contributor", :boolean, default: nil
+        TestModel.reset_column_information
+        assert_not TestModel.new.contributor?
+        assert_nil TestModel.new.contributor
+      end
+
+      def test_change_column_to_drop_default_with_null_false
+        add_column "test_models", "contributor", :boolean, default: true, null: false
         assert TestModel.new.contributor?
 
-        change_column "test_models", "contributor", :boolean, :default => nil
+        change_column "test_models", "contributor", :boolean, default: nil, null: false
         TestModel.reset_column_information
         assert_not TestModel.new.contributor?
         assert_nil TestModel.new.contributor
       end
 
       def test_change_column_with_new_default
-        add_column "test_models", "administrator", :boolean, :default => true
+        add_column "test_models", "administrator", :boolean, default: true
         assert TestModel.new.administrator?
 
-        change_column "test_models", "administrator", :boolean, :default => false
+        change_column "test_models", "administrator", :boolean, default: false
         TestModel.reset_column_information
         assert_not TestModel.new.administrator?
       end
 
       def test_change_column_with_custom_index_name
         add_column "test_models", "category", :string
-        add_index :test_models, :category, name: 'test_models_categories_idx'
+        add_index :test_models, :category, name: "test_models_categories_idx"
 
-        assert_equal ['test_models_categories_idx'], connection.indexes('test_models').map(&:name)
-        change_column "test_models", "category", :string, null: false, default: 'article'
+        assert_equal ["test_models_categories_idx"], connection.indexes("test_models").map(&:name)
+        change_column "test_models", "category", :string, null: false, default: "article"
 
-        assert_equal ['test_models_categories_idx'], connection.indexes('test_models').map(&:name)
+        assert_equal ["test_models_categories_idx"], connection.indexes("test_models").map(&:name)
       end
 
       def test_change_column_with_long_index_name
-        table_name_prefix = 'test_models_'
-        long_index_name = table_name_prefix + ('x' * (connection.allowed_index_name_length - table_name_prefix.length))
+        table_name_prefix = "test_models_"
+        long_index_name = table_name_prefix + ("x" * (connection.allowed_index_name_length - table_name_prefix.length))
         add_column "test_models", "category", :string
         add_index :test_models, :category, name: long_index_name
 
-        change_column "test_models", "category", :string, null: false, default: 'article'
+        change_column "test_models", "category", :string, null: false, default: "article"
 
-        assert_equal [long_index_name], connection.indexes('test_models').map(&:name)
+        assert_equal [long_index_name], connection.indexes("test_models").map(&:name)
       end
 
       def test_change_column_default
@@ -287,7 +304,7 @@ module ActiveRecord
         remove_column("my_table", "col_two")
         rename_column("my_table", "col_one", "col_three")
 
-        assert_equal 'my_table_id', connection.primary_key('my_table')
+        assert_equal "my_table_id", connection.primary_key("my_table")
       ensure
         connection.drop_table(:my_table) rescue nil
       end
diff --git a/activerecord/test/cases/migration/command_recorder_test.rb b/activerecord/test/cases/migration/command_recorder_test.rb
index 1e3529db54..58bc558619 100644
--- a/activerecord/test/cases/migration/command_recorder_test.rb
+++ b/activerecord/test/cases/migration/command_recorder_test.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require "cases/helper"
 
 module ActiveRecord
@@ -25,26 +27,26 @@ module ActiveRecord
         recorder = CommandRecorder.new(Class.new {
           def create_table(name); end
         }.new)
-        assert recorder.respond_to?(:create_table), 'respond_to? create_table'
+        assert recorder.respond_to?(:create_table), "respond_to? create_table"
         recorder.send(:create_table, :horses)
         assert_equal [[:create_table, [:horses], nil]], recorder.commands
       end
 
       def test_unknown_commands_delegate
         recorder = Struct.new(:foo)
-        recorder = CommandRecorder.new(recorder.new('bar'))
-        assert_equal 'bar', recorder.foo
+        recorder = CommandRecorder.new(recorder.new("bar"))
+        assert_equal "bar", recorder.foo
       end
 
       def test_inverse_of_raise_exception_on_unknown_commands
         assert_raises(ActiveRecord::IrreversibleMigration) do
-          @recorder.inverse_of :execute, ['some sql']
+          @recorder.inverse_of :execute, ["some sql"]
         end
       end
 
       def test_irreversible_commands_raise_exception
         assert_raises(ActiveRecord::IrreversibleMigration) do
-          @recorder.revert{ @recorder.execute 'some sql' }
+          @recorder.revert { @recorder.execute "some sql" }
         end
       end
 
@@ -58,12 +60,12 @@ module ActiveRecord
           @recorder.record :create_table, [:hello]
           @recorder.record :create_table, [:world]
         end
-        tables = @recorder.commands.map{|_cmd, args, _block| args}
+        tables = @recorder.commands.map { |_cmd, args, _block| args }
         assert_equal [[:world], [:hello]], tables
       end
 
       def test_revert_order
-        block = Proc.new{|t| t.string :name }
+        block = Proc.new { |t| t.string :name }
         @recorder.instance_eval do
           create_table("apples", &block)
           revert do
@@ -115,13 +117,13 @@ module ActiveRecord
       end
 
       def test_invert_create_table_with_options_and_block
-        block = Proc.new{}
+        block = Proc.new {}
         drop_table = @recorder.inverse_of :create_table, [:people_reminders, id: false], &block
         assert_equal [:drop_table, [:people_reminders, id: false], block], drop_table
       end
 
       def test_invert_drop_table
-        block = Proc.new{}
+        block = Proc.new {}
         create_table = @recorder.inverse_of :drop_table, [:people_reminders, id: false], &block
         assert_equal [:create_table, [:people_reminders, id: false], block], create_table
       end
@@ -143,7 +145,7 @@ module ActiveRecord
       end
 
       def test_invert_drop_join_table
-        block = Proc.new{}
+        block = Proc.new {}
         create_join_table = @recorder.inverse_of :drop_join_table, [:musics, :artists, table_name: :catalog], &block
         assert_equal [:create_join_table, [:musics, :artists, table_name: :catalog], block], create_join_table
       end
@@ -166,7 +168,7 @@ module ActiveRecord
 
       def test_invert_change_column_default
         assert_raises(ActiveRecord::IrreversibleMigration) do
-          @recorder.inverse_of :change_column_default, [:table, :column, 'default_value']
+          @recorder.inverse_of :change_column_default, [:table, :column, "default_value"]
         end
       end
 
@@ -203,17 +205,17 @@ module ActiveRecord
 
       def test_invert_add_index
         remove = @recorder.inverse_of :add_index, [:table, [:one, :two]]
-        assert_equal [:remove_index, [:table, {column: [:one, :two]}]], remove
+        assert_equal [:remove_index, [:table, { column: [:one, :two] }]], remove
       end
 
       def test_invert_add_index_with_name
         remove = @recorder.inverse_of :add_index, [:table, [:one, :two], name: "new_index"]
-        assert_equal [:remove_index, [:table, {name: "new_index"}]], remove
+        assert_equal [:remove_index, [:table, { name: "new_index" }]], remove
       end
 
-      def test_invert_add_index_with_no_options
-        remove = @recorder.inverse_of :add_index, [:table, [:one, :two]]
-        assert_equal [:remove_index, [:table, {column: [:one, :two]}]], remove
+      def test_invert_add_index_with_algorithm_option
+        remove = @recorder.inverse_of :add_index, [:table, :one, algorithm: :concurrently]
+        assert_equal [:remove_index, [:table, { column: :one, algorithm: :concurrently }]], remove
       end
 
       def test_invert_remove_index
@@ -222,17 +224,17 @@ module ActiveRecord
       end
 
       def test_invert_remove_index_with_column
-        add = @recorder.inverse_of :remove_index, [:table, {column: [:one, :two], options: true}]
+        add = @recorder.inverse_of :remove_index, [:table, { column: [:one, :two], options: true }]
         assert_equal [:add_index, [:table, [:one, :two], options: true]], add
       end
 
       def test_invert_remove_index_with_name
-        add = @recorder.inverse_of :remove_index, [:table, {column: [:one, :two], name: "new_index"}]
+        add = @recorder.inverse_of :remove_index, [:table, { column: [:one, :two], name: "new_index" }]
         assert_equal [:add_index, [:table, [:one, :two], name: "new_index"]], add
       end
 
       def test_invert_remove_index_with_no_special_options
-        add = @recorder.inverse_of :remove_index, [:table, {column: [:one, :two]}]
+        add = @recorder.inverse_of :remove_index, [:table, { column: [:one, :two] }]
         assert_equal [:add_index, [:table, [:one, :two], {}]], add
       end
 
@@ -254,7 +256,7 @@ module ActiveRecord
 
       def test_invert_remove_timestamps
         add = @recorder.inverse_of :remove_timestamps, [:table, { null: true }]
-        assert_equal [:add_timestamps, [:table, {null: true }], nil], add
+        assert_equal [:add_timestamps, [:table, { null: true }], nil], add
       end
 
       def test_invert_add_reference
@@ -283,13 +285,13 @@ module ActiveRecord
       end
 
       def test_invert_enable_extension
-        disable = @recorder.inverse_of :enable_extension, ['uuid-ossp']
-        assert_equal [:disable_extension, ['uuid-ossp'], nil], disable
+        disable = @recorder.inverse_of :enable_extension, ["uuid-ossp"]
+        assert_equal [:disable_extension, ["uuid-ossp"], nil], disable
       end
 
       def test_invert_disable_extension
-        enable = @recorder.inverse_of :disable_extension, ['uuid-ossp']
-        assert_equal [:enable_extension, ['uuid-ossp'], nil], enable
+        enable = @recorder.inverse_of :disable_extension, ["uuid-ossp"]
+        assert_equal [:enable_extension, ["uuid-ossp"], nil], enable
       end
 
       def test_invert_add_foreign_key
diff --git a/activerecord/test/cases/migration/compatibility_test.rb b/activerecord/test/cases/migration/compatibility_test.rb
index 60ca90464d..26d3b3e29d 100644
--- a/activerecord/test/cases/migration/compatibility_test.rb
+++ b/activerecord/test/cases/migration/compatibility_test.rb
@@ -1,4 +1,7 @@
-require 'cases/helper'
+# frozen_string_literal: true
+
+require "cases/helper"
+require "support/schema_dumping_helper"
 
 module ActiveRecord
   class Migration
@@ -13,8 +16,8 @@ module ActiveRecord
         ActiveRecord::Migration.verbose = false
 
         connection.create_table :testings do |t|
-          t.column :foo, :string, :limit => 100
-          t.column :bar, :string, :limit => 100
+          t.column :foo, :string, limit: 5
+          t.column :bar, :string, limit: 100
         end
       end
 
@@ -25,7 +28,7 @@ module ActiveRecord
       end
 
       def test_migration_doesnt_remove_named_index
-        connection.add_index :testings, :foo, :name => "custom_index_name"
+        connection.add_index :testings, :foo, name: "custom_index_name"
 
         migration = Class.new(ActiveRecord::Migration[4.2]) {
           def version; 101 end
@@ -55,7 +58,7 @@ module ActiveRecord
       end
 
       def test_references_does_not_add_index_by_default
-        migration = Class.new(ActiveRecord::Migration) {
+        migration = Class.new(ActiveRecord::Migration[4.2]) {
           def migrate(x)
             create_table :more_testings do |t|
               t.references :foo
@@ -73,7 +76,7 @@ module ActiveRecord
       end
 
       def test_timestamps_have_null_constraints_if_not_present_in_migration_of_create_table
-        migration = Class.new(ActiveRecord::Migration) {
+        migration = Class.new(ActiveRecord::Migration[4.2]) {
           def migrate(x)
             create_table :more_testings do |t|
               t.timestamps
@@ -83,14 +86,29 @@ module ActiveRecord
 
         ActiveRecord::Migrator.new(:up, [migration]).migrate
 
-        assert connection.columns(:more_testings).find { |c| c.name == 'created_at' }.null
-        assert connection.columns(:more_testings).find { |c| c.name == 'updated_at' }.null
+        assert connection.columns(:more_testings).find { |c| c.name == "created_at" }.null
+        assert connection.columns(:more_testings).find { |c| c.name == "updated_at" }.null
       ensure
         connection.drop_table :more_testings rescue nil
       end
 
+      def test_timestamps_have_null_constraints_if_not_present_in_migration_of_change_table
+        migration = Class.new(ActiveRecord::Migration[4.2]) {
+          def migrate(x)
+            change_table :testings do |t|
+              t.timestamps
+            end
+          end
+        }.new
+
+        ActiveRecord::Migrator.new(:up, [migration]).migrate
+
+        assert connection.columns(:testings).find { |c| c.name == "created_at" }.null
+        assert connection.columns(:testings).find { |c| c.name == "updated_at" }.null
+      end
+
       def test_timestamps_have_null_constraints_if_not_present_in_migration_for_adding_timestamps_to_existing_table
-        migration = Class.new(ActiveRecord::Migration) {
+        migration = Class.new(ActiveRecord::Migration[4.2]) {
           def migrate(x)
             add_timestamps :testings
           end
@@ -98,21 +116,254 @@ module ActiveRecord
 
         ActiveRecord::Migrator.new(:up, [migration]).migrate
 
-        assert connection.columns(:testings).find { |c| c.name == 'created_at' }.null
-        assert connection.columns(:testings).find { |c| c.name == 'updated_at' }.null
+        assert connection.columns(:testings).find { |c| c.name == "created_at" }.null
+        assert connection.columns(:testings).find { |c| c.name == "updated_at" }.null
       end
 
-      def test_legacy_migrations_get_deprecation_warning_when_run
-        migration = Class.new(ActiveRecord::Migration) {
-          def up
-            add_column :testings, :baz, :string
-          end
-        }
+      def test_legacy_migrations_raises_exception_when_inherited
+        e = assert_raises(StandardError) do
+          class_eval("class LegacyMigration < ActiveRecord::Migration; end")
+        end
+        assert_match(/LegacyMigration < ActiveRecord::Migration\[4\.2\]/, e.message)
+      end
+
+      if current_adapter?(:PostgreSQLAdapter)
+        class Testing < ActiveRecord::Base
+        end
+
+        def test_legacy_change_column_with_null_executes_update
+          migration = Class.new(ActiveRecord::Migration[5.1]) {
+            def migrate(x)
+              change_column :testings, :foo, :string, limit: 10, null: false, default: "foobar"
+            end
+          }.new
+
+          Testing.create!
+          ActiveRecord::Migrator.new(:up, [migration]).migrate
+          assert_equal ["foobar"], Testing.all.map(&:foo)
+        ensure
+          ActiveRecord::Base.clear_cache!
+        end
+      end
+    end
+  end
+end
 
-        assert_deprecated do
-          migration.migrate :up
+module LegacyPrimaryKeyTestCases
+  include SchemaDumpingHelper
+
+  class LegacyPrimaryKey < ActiveRecord::Base
+  end
+
+  def setup
+    @migration = nil
+    @verbose_was = ActiveRecord::Migration.verbose
+    ActiveRecord::Migration.verbose = false
+  end
+
+  def teardown
+    @migration.migrate(:down) if @migration
+    ActiveRecord::Migration.verbose = @verbose_was
+    ActiveRecord::SchemaMigration.delete_all rescue nil
+    LegacyPrimaryKey.reset_column_information
+  end
+
+  def test_legacy_primary_key_should_be_auto_incremented
+    @migration = Class.new(migration_class) {
+      def change
+        create_table :legacy_primary_keys do |t|
+          t.references :legacy_ref
+        end
+      end
+    }.new
+
+    @migration.migrate(:up)
+
+    assert_legacy_primary_key
+
+    legacy_ref = LegacyPrimaryKey.columns_hash["legacy_ref_id"]
+    assert_not legacy_ref.bigint?
+
+    record1 = LegacyPrimaryKey.create!
+    assert_not_nil record1.id
+
+    record1.destroy
+
+    record2 = LegacyPrimaryKey.create!
+    assert_not_nil record2.id
+    assert_operator record2.id, :>, record1.id
+  end
+
+  def test_legacy_integer_primary_key_should_not_be_auto_incremented
+    skip if current_adapter?(:SQLite3Adapter)
+
+    @migration = Class.new(migration_class) {
+      def change
+        create_table :legacy_primary_keys, id: :integer do |t|
         end
       end
+    }.new
+
+    @migration.migrate(:up)
+
+    assert_raises(ActiveRecord::NotNullViolation) do
+      LegacyPrimaryKey.create!
     end
+
+    schema = dump_table_schema "legacy_primary_keys"
+    assert_match %r{create_table "legacy_primary_keys", id: :integer, default: nil}, schema
+  end
+
+  def test_legacy_primary_key_in_create_table_should_be_integer
+    @migration = Class.new(migration_class) {
+      def change
+        create_table :legacy_primary_keys, id: false do |t|
+          t.primary_key :id
+        end
+      end
+    }.new
+
+    @migration.migrate(:up)
+
+    assert_legacy_primary_key
+  end
+
+  def test_legacy_primary_key_in_change_table_should_be_integer
+    @migration = Class.new(migration_class) {
+      def change
+        create_table :legacy_primary_keys, id: false do |t|
+          t.integer :dummy
+        end
+        change_table :legacy_primary_keys do |t|
+          t.primary_key :id
+        end
+      end
+    }.new
+
+    @migration.migrate(:up)
+
+    assert_legacy_primary_key
+  end
+
+  def test_add_column_with_legacy_primary_key_should_be_integer
+    @migration = Class.new(migration_class) {
+      def change
+        create_table :legacy_primary_keys, id: false do |t|
+          t.integer :dummy
+        end
+        add_column :legacy_primary_keys, :id, :primary_key
+      end
+    }.new
+
+    @migration.migrate(:up)
+
+    assert_legacy_primary_key
+  end
+
+  def test_legacy_join_table_foreign_keys_should_be_integer
+    @migration = Class.new(migration_class) {
+      def change
+        create_join_table :apples, :bananas do |t|
+        end
+      end
+    }.new
+
+    @migration.migrate(:up)
+
+    schema = dump_table_schema "apples_bananas"
+    assert_match %r{integer "apple_id", null: false}, schema
+    assert_match %r{integer "banana_id", null: false}, schema
+  end
+
+  def test_legacy_join_table_column_options_should_be_overwritten
+    @migration = Class.new(migration_class) {
+      def change
+        create_join_table :apples, :bananas, column_options: { type: :bigint } do |t|
+        end
+      end
+    }.new
+
+    @migration.migrate(:up)
+
+    schema = dump_table_schema "apples_bananas"
+    assert_match %r{bigint "apple_id", null: false}, schema
+    assert_match %r{bigint "banana_id", null: false}, schema
+  end
+
+  if current_adapter?(:Mysql2Adapter)
+    def test_legacy_bigint_primary_key_should_be_auto_incremented
+      @migration = Class.new(migration_class) {
+        def change
+          create_table :legacy_primary_keys, id: :bigint
+        end
+      }.new
+
+      @migration.migrate(:up)
+
+      legacy_pk = LegacyPrimaryKey.columns_hash["id"]
+      assert legacy_pk.bigint?
+      assert legacy_pk.auto_increment?
+
+      schema = dump_table_schema "legacy_primary_keys"
+      assert_match %r{create_table "legacy_primary_keys", (?!id: :bigint, default: nil)}, schema
+    end
+  else
+    def test_legacy_bigint_primary_key_should_not_be_auto_incremented
+      @migration = Class.new(migration_class) {
+        def change
+          create_table :legacy_primary_keys, id: :bigint do |t|
+          end
+        end
+      }.new
+
+      @migration.migrate(:up)
+
+      assert_raises(ActiveRecord::NotNullViolation) do
+        LegacyPrimaryKey.create!
+      end
+
+      schema = dump_table_schema "legacy_primary_keys"
+      assert_match %r{create_table "legacy_primary_keys", id: :bigint, default: nil}, schema
+    end
+  end
+
+  private
+    def assert_legacy_primary_key
+      assert_equal "id", LegacyPrimaryKey.primary_key
+
+      legacy_pk = LegacyPrimaryKey.columns_hash["id"]
+
+      assert_equal :integer, legacy_pk.type
+      assert_not legacy_pk.bigint?
+      assert_not legacy_pk.null
+
+      if current_adapter?(:Mysql2Adapter, :PostgreSQLAdapter)
+        schema = dump_table_schema "legacy_primary_keys"
+        assert_match %r{create_table "legacy_primary_keys", id: :(?:integer|serial), (?!default: nil)}, schema
+      end
+    end
+end
+
+module LegacyPrimaryKeyTest
+  class V5_0 < ActiveRecord::TestCase
+    include LegacyPrimaryKeyTestCases
+
+    self.use_transactional_tests = false
+
+    private
+      def migration_class
+        ActiveRecord::Migration[5.0]
+      end
+  end
+
+  class V4_2 < ActiveRecord::TestCase
+    include LegacyPrimaryKeyTestCases
+
+    self.use_transactional_tests = false
+
+    private
+      def migration_class
+        ActiveRecord::Migration[4.2]
+      end
   end
 end
diff --git a/activerecord/test/cases/migration/create_join_table_test.rb b/activerecord/test/cases/migration/create_join_table_test.rb
index 920c472c73..77d32a24a5 100644
--- a/activerecord/test/cases/migration/create_join_table_test.rb
+++ b/activerecord/test/cases/migration/create_join_table_test.rb
@@ -1,4 +1,6 @@
-require 'cases/helper'
+# frozen_string_literal: true
+
+require "cases/helper"
 
 module ActiveRecord
   class Migration
@@ -12,9 +14,7 @@ module ActiveRecord
 
       teardown do
         %w(artists_musics musics_videos catalog).each do |table_name|
-          ActiveSupport::Deprecation.silence do
-            connection.drop_table table_name if connection.table_exists?(table_name)
-          end
+          connection.drop_table table_name, if_exists: true
         end
       end
 
@@ -31,13 +31,13 @@ module ActiveRecord
       end
 
       def test_create_join_table_with_strings
-        connection.create_join_table 'artists', 'musics'
+        connection.create_join_table "artists", "musics"
 
         assert_equal %w(artist_id music_id), connection.columns(:artists_musics).map(&:name).sort
       end
 
       def test_create_join_table_with_symbol_and_string
-        connection.create_join_table :artists, 'musics'
+        connection.create_join_table :artists, "musics"
 
         assert_equal %w(artist_id music_id), connection.columns(:artists_musics).map(&:name).sort
       end
@@ -55,13 +55,13 @@ module ActiveRecord
       end
 
       def test_create_join_table_with_the_table_name_as_string
-        connection.create_join_table :artists, :musics, table_name: 'catalog'
+        connection.create_join_table :artists, :musics, table_name: "catalog"
 
         assert_equal %w(artist_id music_id), connection.columns(:catalog).map(&:name).sort
       end
 
       def test_create_join_table_with_column_options
-        connection.create_join_table :artists, :musics, column_options: {null: true}
+        connection.create_join_table :artists, :musics, column_options: { null: true }
 
         assert_equal [true, true], connection.columns(:artists_musics).map(&:null)
       end
@@ -80,55 +80,66 @@ module ActiveRecord
         assert_equal [%w(artist_id music_id)], connection.indexes(:artists_musics).map(&:columns)
       end
 
+      def test_create_join_table_respects_reference_key_type
+        connection.create_join_table :artists, :musics do |t|
+          t.references :video
+        end
+
+        artist_id, music_id, video_id = connection.columns(:artists_musics).sort_by(&:name)
+
+        assert_equal video_id.sql_type, artist_id.sql_type
+        assert_equal video_id.sql_type, music_id.sql_type
+      end
+
       def test_drop_join_table
         connection.create_join_table :artists, :musics
         connection.drop_join_table :artists, :musics
 
-        ActiveSupport::Deprecation.silence { assert !connection.table_exists?('artists_musics') }
+        assert !connection.table_exists?("artists_musics")
       end
 
       def test_drop_join_table_with_strings
         connection.create_join_table :artists, :musics
-        connection.drop_join_table 'artists', 'musics'
+        connection.drop_join_table "artists", "musics"
 
-        ActiveSupport::Deprecation.silence { assert !connection.table_exists?('artists_musics') }
+        assert !connection.table_exists?("artists_musics")
       end
 
       def test_drop_join_table_with_the_proper_order
         connection.create_join_table :videos, :musics
         connection.drop_join_table :videos, :musics
 
-        ActiveSupport::Deprecation.silence { assert !connection.table_exists?('musics_videos') }
+        assert !connection.table_exists?("musics_videos")
       end
 
       def test_drop_join_table_with_the_table_name
         connection.create_join_table :artists, :musics, table_name: :catalog
         connection.drop_join_table :artists, :musics, table_name: :catalog
 
-        ActiveSupport::Deprecation.silence { assert !connection.table_exists?('catalog') }
+        assert !connection.table_exists?("catalog")
       end
 
       def test_drop_join_table_with_the_table_name_as_string
-        connection.create_join_table :artists, :musics, table_name: 'catalog'
-        connection.drop_join_table :artists, :musics, table_name: 'catalog'
+        connection.create_join_table :artists, :musics, table_name: "catalog"
+        connection.drop_join_table :artists, :musics, table_name: "catalog"
 
-        ActiveSupport::Deprecation.silence { assert !connection.table_exists?('catalog') }
+        assert !connection.table_exists?("catalog")
       end
 
       def test_drop_join_table_with_column_options
-        connection.create_join_table :artists, :musics, column_options: {null: true}
-        connection.drop_join_table :artists, :musics, column_options: {null: true}
+        connection.create_join_table :artists, :musics, column_options: { null: true }
+        connection.drop_join_table :artists, :musics, column_options: { null: true }
 
-        ActiveSupport::Deprecation.silence { assert !connection.table_exists?('artists_musics') }
+        assert !connection.table_exists?("artists_musics")
       end
 
       def test_create_and_drop_join_table_with_common_prefix
         with_table_cleanup do
-          connection.create_join_table 'audio_artists', 'audio_musics'
-          ActiveSupport::Deprecation.silence { assert connection.table_exists?('audio_artists_musics') }
+          connection.create_join_table "audio_artists", "audio_musics"
+          assert connection.table_exists?("audio_artists_musics")
 
-          connection.drop_join_table 'audio_artists', 'audio_musics'
-          ActiveSupport::Deprecation.silence { assert !connection.table_exists?('audio_artists_musics'), "Should have dropped join table, but didn't" }
+          connection.drop_join_table "audio_artists", "audio_musics"
+          assert !connection.table_exists?("audio_artists_musics"), "Should have dropped join table, but didn't"
         end
       end
 
diff --git a/activerecord/test/cases/migration/foreign_key_test.rb b/activerecord/test/cases/migration/foreign_key_test.rb
index 01162dcefe..079be04946 100644
--- a/activerecord/test/cases/migration/foreign_key_test.rb
+++ b/activerecord/test/cases/migration/foreign_key_test.rb
@@ -1,84 +1,105 @@
-require 'cases/helper'
-require 'support/ddl_helper'
-require 'support/schema_dumping_helper'
+# frozen_string_literal: true
 
-if ActiveRecord::Base.connection.supports_foreign_keys?
-module ActiveRecord
-  class Migration
-    class ForeignKeyTest < ActiveRecord::TestCase
-      include DdlHelper
-      include SchemaDumpingHelper
-      include ActiveSupport::Testing::Stream
-
-      class Rocket < ActiveRecord::Base
-      end
+require "cases/helper"
+require "support/schema_dumping_helper"
 
-      class Astronaut < ActiveRecord::Base
+if ActiveRecord::Base.connection.supports_foreign_keys_in_create?
+  module ActiveRecord
+    class Migration
+      class ForeignKeyInCreateTest < ActiveRecord::TestCase
+        def test_foreign_keys
+          foreign_keys = ActiveRecord::Base.connection.foreign_keys("fk_test_has_fk")
+          assert_equal 1, foreign_keys.size
+
+          fk = foreign_keys.first
+          assert_equal "fk_test_has_fk", fk.from_table
+          assert_equal "fk_test_has_pk", fk.to_table
+          assert_equal "fk_id", fk.column
+          assert_equal "pk_id", fk.primary_key
+          assert_equal "fk_name", fk.name unless current_adapter?(:SQLite3Adapter)
+        end
       end
+    end
+  end
+end
 
-      setup do
-        @connection = ActiveRecord::Base.connection
-        @connection.create_table "rockets", force: true do |t|
-          t.string :name
+if ActiveRecord::Base.connection.supports_foreign_keys?
+  module ActiveRecord
+    class Migration
+      class ForeignKeyTest < ActiveRecord::TestCase
+        include SchemaDumpingHelper
+        include ActiveSupport::Testing::Stream
+
+        class Rocket < ActiveRecord::Base
         end
 
-        @connection.create_table "astronauts", force: true do |t|
-          t.string :name
-          t.references :rocket
+        class Astronaut < ActiveRecord::Base
+        end
+
+        setup do
+          @connection = ActiveRecord::Base.connection
+          @connection.create_table "rockets", force: true do |t|
+            t.string :name
+          end
+
+          @connection.create_table "astronauts", force: true do |t|
+            t.string :name
+            t.references :rocket
+          end
         end
-      end
 
-      teardown do
-        if defined?(@connection)
+        teardown do
           @connection.drop_table "astronauts", if_exists: true
           @connection.drop_table "rockets", if_exists: true
         end
-      end
 
-      def test_foreign_keys
-        foreign_keys = @connection.foreign_keys("fk_test_has_fk")
-        assert_equal 1, foreign_keys.size
+        def test_foreign_keys
+          foreign_keys = @connection.foreign_keys("fk_test_has_fk")
+          assert_equal 1, foreign_keys.size
 
-        fk = foreign_keys.first
-        assert_equal "fk_test_has_fk", fk.from_table
-        assert_equal "fk_test_has_pk", fk.to_table
-        assert_equal "fk_id", fk.column
-        assert_equal "pk_id", fk.primary_key
-        assert_equal "fk_name", fk.name
-      end
+          fk = foreign_keys.first
+          assert_equal "fk_test_has_fk", fk.from_table
+          assert_equal "fk_test_has_pk", fk.to_table
+          assert_equal "fk_id", fk.column
+          assert_equal "pk_id", fk.primary_key
+          assert_equal "fk_name", fk.name
+        end
 
-      def test_add_foreign_key_inferes_column
-        @connection.add_foreign_key :astronauts, :rockets
+        def test_add_foreign_key_inferes_column
+          @connection.add_foreign_key :astronauts, :rockets
 
-        foreign_keys = @connection.foreign_keys("astronauts")
-        assert_equal 1, foreign_keys.size
+          foreign_keys = @connection.foreign_keys("astronauts")
+          assert_equal 1, foreign_keys.size
 
-        fk = foreign_keys.first
-        assert_equal "astronauts", fk.from_table
-        assert_equal "rockets", fk.to_table
-        assert_equal "rocket_id", fk.column
-        assert_equal "id", fk.primary_key
-        assert_equal("fk_rails_78146ddd2e", fk.name)
-      end
+          fk = foreign_keys.first
+          assert_equal "astronauts", fk.from_table
+          assert_equal "rockets", fk.to_table
+          assert_equal "rocket_id", fk.column
+          assert_equal "id", fk.primary_key
+          assert_equal("fk_rails_78146ddd2e", fk.name)
+        end
 
-      def test_add_foreign_key_with_column
-        @connection.add_foreign_key :astronauts, :rockets, column: "rocket_id"
+        def test_add_foreign_key_with_column
+          @connection.add_foreign_key :astronauts, :rockets, column: "rocket_id"
 
-        foreign_keys = @connection.foreign_keys("astronauts")
-        assert_equal 1, foreign_keys.size
+          foreign_keys = @connection.foreign_keys("astronauts")
+          assert_equal 1, foreign_keys.size
 
-        fk = foreign_keys.first
-        assert_equal "astronauts", fk.from_table
-        assert_equal "rockets", fk.to_table
-        assert_equal "rocket_id", fk.column
-        assert_equal "id", fk.primary_key
-        assert_equal("fk_rails_78146ddd2e", fk.name)
-      end
+          fk = foreign_keys.first
+          assert_equal "astronauts", fk.from_table
+          assert_equal "rockets", fk.to_table
+          assert_equal "rocket_id", fk.column
+          assert_equal "id", fk.primary_key
+          assert_equal("fk_rails_78146ddd2e", fk.name)
+        end
+
+        def test_add_foreign_key_with_non_standard_primary_key
+          @connection.create_table :space_shuttles, id: false, force: true do |t|
+            t.bigint :pk, primary_key: true
+          end
 
-      def test_add_foreign_key_with_non_standard_primary_key
-        with_example_table @connection, "space_shuttles", "pk integer PRIMARY KEY" do
           @connection.add_foreign_key(:astronauts, :space_shuttles,
-                                      column: "rocket_id", primary_key: "pk", name: "custom_pk")
+            column: "rocket_id", primary_key: "pk", name: "custom_pk")
 
           foreign_keys = @connection.foreign_keys("astronauts")
           assert_equal 1, foreign_keys.size
@@ -87,218 +108,300 @@ module ActiveRecord
           assert_equal "astronauts", fk.from_table
           assert_equal "space_shuttles", fk.to_table
           assert_equal "pk", fk.primary_key
-
+        ensure
           @connection.remove_foreign_key :astronauts, name: "custom_pk"
+          @connection.drop_table :space_shuttles
         end
-      end
 
-      def test_add_on_delete_restrict_foreign_key
-        @connection.add_foreign_key :astronauts, :rockets, column: "rocket_id", on_delete: :restrict
+        def test_add_on_delete_restrict_foreign_key
+          @connection.add_foreign_key :astronauts, :rockets, column: "rocket_id", on_delete: :restrict
 
-        foreign_keys = @connection.foreign_keys("astronauts")
-        assert_equal 1, foreign_keys.size
+          foreign_keys = @connection.foreign_keys("astronauts")
+          assert_equal 1, foreign_keys.size
 
-        fk = foreign_keys.first
-        if current_adapter?(:Mysql2Adapter)
-          # ON DELETE RESTRICT is the default on MySQL
-          assert_equal nil, fk.on_delete
-        else
-          assert_equal :restrict, fk.on_delete
+          fk = foreign_keys.first
+          if current_adapter?(:Mysql2Adapter)
+            # ON DELETE RESTRICT is the default on MySQL
+            assert_nil fk.on_delete
+          else
+            assert_equal :restrict, fk.on_delete
+          end
         end
-      end
 
-      def test_add_on_delete_cascade_foreign_key
-        @connection.add_foreign_key :astronauts, :rockets, column: "rocket_id", on_delete: :cascade
+        def test_add_on_delete_cascade_foreign_key
+          @connection.add_foreign_key :astronauts, :rockets, column: "rocket_id", on_delete: :cascade
 
-        foreign_keys = @connection.foreign_keys("astronauts")
-        assert_equal 1, foreign_keys.size
+          foreign_keys = @connection.foreign_keys("astronauts")
+          assert_equal 1, foreign_keys.size
 
-        fk = foreign_keys.first
-        assert_equal :cascade, fk.on_delete
-      end
+          fk = foreign_keys.first
+          assert_equal :cascade, fk.on_delete
+        end
 
-      def test_add_on_delete_nullify_foreign_key
-        @connection.add_foreign_key :astronauts, :rockets, column: "rocket_id", on_delete: :nullify
+        def test_add_on_delete_nullify_foreign_key
+          @connection.add_foreign_key :astronauts, :rockets, column: "rocket_id", on_delete: :nullify
 
-        foreign_keys = @connection.foreign_keys("astronauts")
-        assert_equal 1, foreign_keys.size
+          foreign_keys = @connection.foreign_keys("astronauts")
+          assert_equal 1, foreign_keys.size
 
-        fk = foreign_keys.first
-        assert_equal :nullify, fk.on_delete
-      end
+          fk = foreign_keys.first
+          assert_equal :nullify, fk.on_delete
+        end
 
-      def test_on_update_and_on_delete_raises_with_invalid_values
-        assert_raises ArgumentError do
-          @connection.add_foreign_key :astronauts, :rockets, column: "rocket_id", on_delete: :invalid
+        def test_on_update_and_on_delete_raises_with_invalid_values
+          assert_raises ArgumentError do
+            @connection.add_foreign_key :astronauts, :rockets, column: "rocket_id", on_delete: :invalid
+          end
+
+          assert_raises ArgumentError do
+            @connection.add_foreign_key :astronauts, :rockets, column: "rocket_id", on_update: :invalid
+          end
         end
 
-        assert_raises ArgumentError do
-          @connection.add_foreign_key :astronauts, :rockets, column: "rocket_id", on_update: :invalid
+        def test_add_foreign_key_with_on_update
+          @connection.add_foreign_key :astronauts, :rockets, column: "rocket_id", on_update: :nullify
+
+          foreign_keys = @connection.foreign_keys("astronauts")
+          assert_equal 1, foreign_keys.size
+
+          fk = foreign_keys.first
+          assert_equal :nullify, fk.on_update
         end
-      end
 
-      def test_add_foreign_key_with_on_update
-        @connection.add_foreign_key :astronauts, :rockets, column: "rocket_id", on_update: :nullify
+        def test_foreign_key_exists
+          @connection.add_foreign_key :astronauts, :rockets
 
-        foreign_keys = @connection.foreign_keys("astronauts")
-        assert_equal 1, foreign_keys.size
+          assert @connection.foreign_key_exists?(:astronauts, :rockets)
+          assert_not @connection.foreign_key_exists?(:astronauts, :stars)
+        end
 
-        fk = foreign_keys.first
-        assert_equal :nullify, fk.on_update
-      end
+        def test_foreign_key_exists_by_column
+          @connection.add_foreign_key :astronauts, :rockets, column: "rocket_id"
 
-      def test_foreign_key_exists
-        @connection.add_foreign_key :astronauts, :rockets
+          assert @connection.foreign_key_exists?(:astronauts, column: "rocket_id")
+          assert_not @connection.foreign_key_exists?(:astronauts, column: "star_id")
+        end
 
-        assert @connection.foreign_key_exists?(:astronauts, :rockets)
-        assert_not @connection.foreign_key_exists?(:astronauts, :stars)
-      end
+        def test_foreign_key_exists_by_name
+          @connection.add_foreign_key :astronauts, :rockets, column: "rocket_id", name: "fancy_named_fk"
 
-      def test_foreign_key_exists_by_column
-        @connection.add_foreign_key :astronauts, :rockets, column: "rocket_id"
+          assert @connection.foreign_key_exists?(:astronauts, name: "fancy_named_fk")
+          assert_not @connection.foreign_key_exists?(:astronauts, name: "other_fancy_named_fk")
+        end
 
-        assert @connection.foreign_key_exists?(:astronauts, column: "rocket_id")
-        assert_not @connection.foreign_key_exists?(:astronauts, column: "star_id")
-      end
+        def test_remove_foreign_key_inferes_column
+          @connection.add_foreign_key :astronauts, :rockets
 
-      def test_foreign_key_exists_by_name
-        @connection.add_foreign_key :astronauts, :rockets, column: "rocket_id", name: "fancy_named_fk"
+          assert_equal 1, @connection.foreign_keys("astronauts").size
+          @connection.remove_foreign_key :astronauts, :rockets
+          assert_equal [], @connection.foreign_keys("astronauts")
+        end
 
-        assert @connection.foreign_key_exists?(:astronauts, name: "fancy_named_fk")
-        assert_not @connection.foreign_key_exists?(:astronauts, name: "other_fancy_named_fk")
-      end
+        def test_remove_foreign_key_by_column
+          @connection.add_foreign_key :astronauts, :rockets, column: "rocket_id"
 
-      def test_remove_foreign_key_inferes_column
-        @connection.add_foreign_key :astronauts, :rockets
+          assert_equal 1, @connection.foreign_keys("astronauts").size
+          @connection.remove_foreign_key :astronauts, column: "rocket_id"
+          assert_equal [], @connection.foreign_keys("astronauts")
+        end
 
-        assert_equal 1, @connection.foreign_keys("astronauts").size
-        @connection.remove_foreign_key :astronauts, :rockets
-        assert_equal [], @connection.foreign_keys("astronauts")
-      end
+        def test_remove_foreign_key_by_symbol_column
+          @connection.add_foreign_key :astronauts, :rockets, column: :rocket_id
 
-      def test_remove_foreign_key_by_column
-        @connection.add_foreign_key :astronauts, :rockets, column: "rocket_id"
+          assert_equal 1, @connection.foreign_keys("astronauts").size
+          @connection.remove_foreign_key :astronauts, column: :rocket_id
+          assert_equal [], @connection.foreign_keys("astronauts")
+        end
 
-        assert_equal 1, @connection.foreign_keys("astronauts").size
-        @connection.remove_foreign_key :astronauts, column: "rocket_id"
-        assert_equal [], @connection.foreign_keys("astronauts")
-      end
+        def test_remove_foreign_key_by_name
+          @connection.add_foreign_key :astronauts, :rockets, column: "rocket_id", name: "fancy_named_fk"
 
-      def test_remove_foreign_key_by_symbol_column
-        @connection.add_foreign_key :astronauts, :rockets, column: :rocket_id
+          assert_equal 1, @connection.foreign_keys("astronauts").size
+          @connection.remove_foreign_key :astronauts, name: "fancy_named_fk"
+          assert_equal [], @connection.foreign_keys("astronauts")
+        end
 
-        assert_equal 1, @connection.foreign_keys("astronauts").size
-        @connection.remove_foreign_key :astronauts, column: :rocket_id
-        assert_equal [], @connection.foreign_keys("astronauts")
-      end
+        def test_remove_foreign_non_existing_foreign_key_raises
+          assert_raises ArgumentError do
+            @connection.remove_foreign_key :astronauts, :rockets
+          end
+        end
 
-      def test_remove_foreign_key_by_name
-        @connection.add_foreign_key :astronauts, :rockets, column: "rocket_id", name: "fancy_named_fk"
+        if ActiveRecord::Base.connection.supports_validate_constraints?
+          def test_add_invalid_foreign_key
+            @connection.add_foreign_key :astronauts, :rockets, column: "rocket_id", validate: false
 
-        assert_equal 1, @connection.foreign_keys("astronauts").size
-        @connection.remove_foreign_key :astronauts, name: "fancy_named_fk"
-        assert_equal [], @connection.foreign_keys("astronauts")
-      end
+            foreign_keys = @connection.foreign_keys("astronauts")
+            assert_equal 1, foreign_keys.size
 
-      def test_remove_foreign_non_existing_foreign_key_raises
-        assert_raises ArgumentError do
-          @connection.remove_foreign_key :astronauts, :rockets
+            fk = foreign_keys.first
+            refute fk.validated?
+          end
+
+          def test_validate_foreign_key_infers_column
+            @connection.add_foreign_key :astronauts, :rockets, validate: false
+            refute @connection.foreign_keys("astronauts").first.validated?
+
+            @connection.validate_foreign_key :astronauts, :rockets
+            assert @connection.foreign_keys("astronauts").first.validated?
+          end
+
+          def test_validate_foreign_key_by_column
+            @connection.add_foreign_key :astronauts, :rockets, column: "rocket_id", validate: false
+            refute @connection.foreign_keys("astronauts").first.validated?
+
+            @connection.validate_foreign_key :astronauts, column: "rocket_id"
+            assert @connection.foreign_keys("astronauts").first.validated?
+          end
+
+          def test_validate_foreign_key_by_symbol_column
+            @connection.add_foreign_key :astronauts, :rockets, column: :rocket_id, validate: false
+            refute @connection.foreign_keys("astronauts").first.validated?
+
+            @connection.validate_foreign_key :astronauts, column: :rocket_id
+            assert @connection.foreign_keys("astronauts").first.validated?
+          end
+
+          def test_validate_foreign_key_by_name
+            @connection.add_foreign_key :astronauts, :rockets, column: "rocket_id", name: "fancy_named_fk", validate: false
+            refute @connection.foreign_keys("astronauts").first.validated?
+
+            @connection.validate_foreign_key :astronauts, name: "fancy_named_fk"
+            assert @connection.foreign_keys("astronauts").first.validated?
+          end
+
+          def test_validate_foreign_non_existing_foreign_key_raises
+            assert_raises ArgumentError do
+              @connection.validate_foreign_key :astronauts, :rockets
+            end
+          end
+
+          def test_validate_constraint_by_name
+            @connection.add_foreign_key :astronauts, :rockets, column: "rocket_id", name: "fancy_named_fk", validate: false
+
+            @connection.validate_constraint :astronauts, "fancy_named_fk"
+            assert @connection.foreign_keys("astronauts").first.validated?
+          end
+        else
+          # Foreign key should still be created, but should not be invalid
+          def test_add_invalid_foreign_key
+            @connection.add_foreign_key :astronauts, :rockets, column: "rocket_id", validate: false
+
+            foreign_keys = @connection.foreign_keys("astronauts")
+            assert_equal 1, foreign_keys.size
+
+            fk = foreign_keys.first
+            assert fk.validated?
+          end
         end
-      end
 
-      def test_schema_dumping
-        @connection.add_foreign_key :astronauts, :rockets
-        output = dump_table_schema "astronauts"
-        assert_match %r{\s+add_foreign_key "astronauts", "rockets"$}, output
-      end
+        def test_schema_dumping
+          @connection.add_foreign_key :astronauts, :rockets
+          output = dump_table_schema "astronauts"
+          assert_match %r{\s+add_foreign_key "astronauts", "rockets"$}, output
+        end
 
-      def test_schema_dumping_with_options
-        output = dump_table_schema "fk_test_has_fk"
-        assert_match %r{\s+add_foreign_key "fk_test_has_fk", "fk_test_has_pk", column: "fk_id", primary_key: "pk_id", name: "fk_name"$}, output
-      end
+        def test_schema_dumping_with_options
+          output = dump_table_schema "fk_test_has_fk"
+          assert_match %r{\s+add_foreign_key "fk_test_has_fk", "fk_test_has_pk", column: "fk_id", primary_key: "pk_id", name: "fk_name"$}, output
+        end
 
-      def test_schema_dumping_on_delete_and_on_update_options
-        @connection.add_foreign_key :astronauts, :rockets, column: "rocket_id", on_delete: :nullify, on_update: :cascade
+        def test_schema_dumping_on_delete_and_on_update_options
+          @connection.add_foreign_key :astronauts, :rockets, column: "rocket_id", on_delete: :nullify, on_update: :cascade
 
-        output = dump_table_schema "astronauts"
-        assert_match %r{\s+add_foreign_key "astronauts",.+on_update: :cascade,.+on_delete: :nullify$}, output
-      end
+          output = dump_table_schema "astronauts"
+          assert_match %r{\s+add_foreign_key "astronauts",.+on_update: :cascade,.+on_delete: :nullify$}, output
+        end
 
-      class CreateCitiesAndHousesMigration < ActiveRecord::Migration::Current
-        def change
-          create_table("cities") { |t| }
+        class CreateCitiesAndHousesMigration < ActiveRecord::Migration::Current
+          def change
+            create_table("cities") { |t| }
 
-          create_table("houses") do |t|
-            t.column :city_id, :integer
+            create_table("houses") do |t|
+              t.references :city
+            end
+            add_foreign_key :houses, :cities, column: "city_id"
+
+            # remove and re-add to test that schema is updated and not accidentally cached
+            remove_foreign_key :houses, :cities
+            add_foreign_key :houses, :cities, column: "city_id", on_delete: :cascade
           end
-          add_foreign_key :houses, :cities, column: "city_id"
         end
-      end
 
-      def test_add_foreign_key_is_reversible
-        migration = CreateCitiesAndHousesMigration.new
-        silence_stream($stdout) { migration.migrate(:up) }
-        assert_equal 1, @connection.foreign_keys("houses").size
-      ensure
-        silence_stream($stdout) { migration.migrate(:down) }
-      end
+        def test_add_foreign_key_is_reversible
+          migration = CreateCitiesAndHousesMigration.new
+          silence_stream($stdout) { migration.migrate(:up) }
+          assert_equal 1, @connection.foreign_keys("houses").size
+        ensure
+          silence_stream($stdout) { migration.migrate(:down) }
+        end
 
-      class CreateSchoolsAndClassesMigration < ActiveRecord::Migration::Current
-        def change
-          create_table(:schools)
+        def test_foreign_key_constraint_is_not_cached_incorrectly
+          migration = CreateCitiesAndHousesMigration.new
+          silence_stream($stdout) { migration.migrate(:up) }
+          output = dump_table_schema "houses"
+          assert_match %r{\s+add_foreign_key "houses",.+on_delete: :cascade$}, output
+        ensure
+          silence_stream($stdout) { migration.migrate(:down) }
+        end
+
+        class CreateSchoolsAndClassesMigration < ActiveRecord::Migration::Current
+          def change
+            create_table(:schools)
 
-          create_table(:classes) do |t|
-            t.column :school_id, :integer
+            create_table(:classes) do |t|
+              t.references :school
+            end
+            add_foreign_key :classes, :schools
           end
-          add_foreign_key :classes, :schools
         end
-      end
 
-      def test_add_foreign_key_with_prefix
-        ActiveRecord::Base.table_name_prefix = 'p_'
-        migration = CreateSchoolsAndClassesMigration.new
-        silence_stream($stdout) { migration.migrate(:up) }
-        assert_equal 1, @connection.foreign_keys("p_classes").size
-      ensure
-        silence_stream($stdout) { migration.migrate(:down) }
-        ActiveRecord::Base.table_name_prefix = nil
-      end
+        def test_add_foreign_key_with_prefix
+          ActiveRecord::Base.table_name_prefix = "p_"
+          migration = CreateSchoolsAndClassesMigration.new
+          silence_stream($stdout) { migration.migrate(:up) }
+          assert_equal 1, @connection.foreign_keys("p_classes").size
+        ensure
+          silence_stream($stdout) { migration.migrate(:down) }
+          ActiveRecord::Base.table_name_prefix = nil
+        end
 
-      def test_add_foreign_key_with_suffix
-        ActiveRecord::Base.table_name_suffix = '_s'
-        migration = CreateSchoolsAndClassesMigration.new
-        silence_stream($stdout) { migration.migrate(:up) }
-        assert_equal 1, @connection.foreign_keys("classes_s").size
-      ensure
-        silence_stream($stdout) { migration.migrate(:down) }
-        ActiveRecord::Base.table_name_suffix = nil
+        def test_add_foreign_key_with_suffix
+          ActiveRecord::Base.table_name_suffix = "_s"
+          migration = CreateSchoolsAndClassesMigration.new
+          silence_stream($stdout) { migration.migrate(:up) }
+          assert_equal 1, @connection.foreign_keys("classes_s").size
+        ensure
+          silence_stream($stdout) { migration.migrate(:down) }
+          ActiveRecord::Base.table_name_suffix = nil
+        end
       end
-
     end
   end
-end
 else
-module ActiveRecord
-  class Migration
-    class NoForeignKeySupportTest < ActiveRecord::TestCase
-      setup do
-        @connection = ActiveRecord::Base.connection
-      end
+  module ActiveRecord
+    class Migration
+      class NoForeignKeySupportTest < ActiveRecord::TestCase
+        setup do
+          @connection = ActiveRecord::Base.connection
+        end
 
-      def test_add_foreign_key_should_be_noop
-        @connection.add_foreign_key :clubs, :categories
-      end
+        def test_add_foreign_key_should_be_noop
+          @connection.add_foreign_key :clubs, :categories
+        end
 
-      def test_remove_foreign_key_should_be_noop
-        @connection.remove_foreign_key :clubs, :categories
-      end
+        def test_remove_foreign_key_should_be_noop
+          @connection.remove_foreign_key :clubs, :categories
+        end
 
-      def test_foreign_keys_should_raise_not_implemented
-        assert_raises NotImplementedError do
-          @connection.foreign_keys("clubs")
+        unless current_adapter?(:SQLite3Adapter)
+          def test_foreign_keys_should_raise_not_implemented
+            assert_raises NotImplementedError do
+              @connection.foreign_keys("clubs")
+            end
+          end
         end
       end
     end
   end
 end
-end
diff --git a/activerecord/test/cases/migration/helper.rb b/activerecord/test/cases/migration/helper.rb
index ad85684c0b..c056199140 100644
--- a/activerecord/test/cases/migration/helper.rb
+++ b/activerecord/test/cases/migration/helper.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require "cases/helper"
 
 module ActiveRecord
@@ -33,7 +35,7 @@ module ActiveRecord
 
       private
 
-      delegate(*CONNECTION_METHODS, to: :connection)
+        delegate(*CONNECTION_METHODS, to: :connection)
     end
   end
 end
diff --git a/activerecord/test/cases/migration/index_test.rb b/activerecord/test/cases/migration/index_test.rb
index 5abd37bfa2..b25c6d84bc 100644
--- a/activerecord/test/cases/migration/index_test.rb
+++ b/activerecord/test/cases/migration/index_test.rb
@@ -1,4 +1,6 @@
-require 'cases/helper'
+# frozen_string_literal: true
+
+require "cases/helper"
 
 module ActiveRecord
   class Migration
@@ -11,12 +13,12 @@ module ActiveRecord
         @table_name = :testings
 
         connection.create_table table_name do |t|
-          t.column :foo, :string, :limit => 100
-          t.column :bar, :string, :limit => 100
+          t.column :foo, :string, limit: 100
+          t.column :bar, :string, limit: 100
 
           t.string :first_name
-          t.string :last_name, :limit => 100
-          t.string :key,       :limit => 100
+          t.string :last_name, limit: 100
+          t.string :key,       limit: 100
           t.boolean :administrator
         end
       end
@@ -28,32 +30,29 @@ module ActiveRecord
 
       def test_rename_index
         # keep the names short to make Oracle and similar behave
-        connection.add_index(table_name, [:foo], :name => 'old_idx')
-        connection.rename_index(table_name, 'old_idx', 'new_idx')
+        connection.add_index(table_name, [:foo], name: "old_idx")
+        connection.rename_index(table_name, "old_idx", "new_idx")
 
-        # if the adapter doesn't support the indexes call, pick defaults that let the test pass
-        assert_not connection.index_name_exists?(table_name, 'old_idx', false)
-        assert connection.index_name_exists?(table_name, 'new_idx', true)
+        assert_not connection.index_name_exists?(table_name, "old_idx")
+        assert connection.index_name_exists?(table_name, "new_idx")
       end
 
       def test_rename_index_too_long
-        too_long_index_name = good_index_name + 'x'
+        too_long_index_name = good_index_name + "x"
         # keep the names short to make Oracle and similar behave
-        connection.add_index(table_name, [:foo], :name => 'old_idx')
+        connection.add_index(table_name, [:foo], name: "old_idx")
         e = assert_raises(ArgumentError) {
-          connection.rename_index(table_name, 'old_idx', too_long_index_name)
+          connection.rename_index(table_name, "old_idx", too_long_index_name)
         }
         assert_match(/too long; the limit is #{connection.allowed_index_name_length} characters/, e.message)
 
-        # if the adapter doesn't support the indexes call, pick defaults that let the test pass
-        assert connection.index_name_exists?(table_name, 'old_idx', false)
+        assert connection.index_name_exists?(table_name, "old_idx")
       end
 
-
       def test_double_add_index
-        connection.add_index(table_name, [:foo], :name => 'some_idx')
+        connection.add_index(table_name, [:foo], name: "some_idx")
         assert_raises(ArgumentError) {
-          connection.add_index(table_name, [:foo], :name => 'some_idx')
+          connection.add_index(table_name, [:foo], name: "some_idx")
         }
       end
 
@@ -64,36 +63,36 @@ module ActiveRecord
       def test_add_index_works_with_long_index_names
         connection.add_index(table_name, "foo", name: good_index_name)
 
-        assert connection.index_name_exists?(table_name, good_index_name, false)
+        assert connection.index_name_exists?(table_name, good_index_name)
         connection.remove_index(table_name, name: good_index_name)
       end
 
       def test_add_index_does_not_accept_too_long_index_names
-        too_long_index_name = good_index_name + 'x'
+        too_long_index_name = good_index_name + "x"
 
         e = assert_raises(ArgumentError) {
           connection.add_index(table_name, "foo", name: too_long_index_name)
         }
         assert_match(/too long; the limit is #{connection.allowed_index_name_length} characters/, e.message)
 
-        assert_not connection.index_name_exists?(table_name, too_long_index_name, false)
-        connection.add_index(table_name, "foo", :name => good_index_name)
+        assert_not connection.index_name_exists?(table_name, too_long_index_name)
+        connection.add_index(table_name, "foo", name: good_index_name)
       end
 
       def test_internal_index_with_name_matching_database_limit
-        good_index_name = 'x' * connection.index_name_length
+        good_index_name = "x" * connection.index_name_length
         connection.add_index(table_name, "foo", name: good_index_name, internal: true)
 
-        assert connection.index_name_exists?(table_name, good_index_name, false)
+        assert connection.index_name_exists?(table_name, good_index_name)
         connection.remove_index(table_name, name: good_index_name)
       end
 
       def test_index_symbol_names
-        connection.add_index table_name, :foo, :name => :symbol_index_name
-        assert connection.index_exists?(table_name, :foo, :name => :symbol_index_name)
+        connection.add_index table_name, :foo, name: :symbol_index_name
+        assert connection.index_exists?(table_name, :foo, name: :symbol_index_name)
 
-        connection.remove_index table_name, :name => :symbol_index_name
-        assert_not connection.index_exists?(table_name, :foo, :name => :symbol_index_name)
+        connection.remove_index table_name, name: :symbol_index_name
+        assert_not connection.index_exists?(table_name, :foo, name: :symbol_index_name)
       end
 
       def test_index_exists
@@ -122,21 +121,21 @@ module ActiveRecord
       end
 
       def test_unique_index_exists
-        connection.add_index :testings, :foo, :unique => true
+        connection.add_index :testings, :foo, unique: true
 
-        assert connection.index_exists?(:testings, :foo, :unique => true)
+        assert connection.index_exists?(:testings, :foo, unique: true)
       end
 
       def test_named_index_exists
-        connection.add_index :testings, :foo, :name => "custom_index_name"
+        connection.add_index :testings, :foo, name: "custom_index_name"
 
         assert connection.index_exists?(:testings, :foo)
-        assert connection.index_exists?(:testings, :foo, :name => "custom_index_name")
-        assert !connection.index_exists?(:testings, :foo, :name => "other_index_name")
+        assert connection.index_exists?(:testings, :foo, name: "custom_index_name")
+        assert !connection.index_exists?(:testings, :foo, name: "other_index_name")
       end
 
       def test_remove_named_index
-        connection.add_index :testings, :foo, :name => "custom_index_name"
+        connection.add_index :testings, :foo, name: "custom_index_name"
 
         assert connection.index_exists?(:testings, :foo)
         connection.remove_index :testings, :foo
@@ -144,7 +143,7 @@ module ActiveRecord
       end
 
       def test_add_index_attribute_length_limit
-        connection.add_index :testings, [:foo, :bar], :length => {:foo => 10, :bar => nil}
+        connection.add_index :testings, [:foo, :bar], length: { foo: 10, bar: nil }
 
         assert connection.index_exists?(:testings, [:foo, :bar])
       end
@@ -154,53 +153,53 @@ module ActiveRecord
         connection.remove_index("testings", "last_name")
 
         connection.add_index("testings", ["last_name", "first_name"])
-        connection.remove_index("testings", :column => ["last_name", "first_name"])
+        connection.remove_index("testings", column: ["last_name", "first_name"])
 
         # Oracle adapter cannot have specified index name larger than 30 characters
         # Oracle adapter is shortening index name when just column list is given
         unless current_adapter?(:OracleAdapter)
           connection.add_index("testings", ["last_name", "first_name"])
-          connection.remove_index("testings", :name => :index_testings_on_last_name_and_first_name)
+          connection.remove_index("testings", name: :index_testings_on_last_name_and_first_name)
           connection.add_index("testings", ["last_name", "first_name"])
           connection.remove_index("testings", "last_name_and_first_name")
         end
         connection.add_index("testings", ["last_name", "first_name"])
         connection.remove_index("testings", ["last_name", "first_name"])
 
-        connection.add_index("testings", ["last_name"], :length => 10)
+        connection.add_index("testings", ["last_name"], length: 10)
         connection.remove_index("testings", "last_name")
 
-        connection.add_index("testings", ["last_name"], :length => {:last_name => 10})
+        connection.add_index("testings", ["last_name"], length: { last_name: 10 })
         connection.remove_index("testings", ["last_name"])
 
-        connection.add_index("testings", ["last_name", "first_name"], :length => 10)
+        connection.add_index("testings", ["last_name", "first_name"], length: 10)
         connection.remove_index("testings", ["last_name", "first_name"])
 
-        connection.add_index("testings", ["last_name", "first_name"], :length => {:last_name => 10, :first_name => 20})
+        connection.add_index("testings", ["last_name", "first_name"], length: { last_name: 10, first_name: 20 })
         connection.remove_index("testings", ["last_name", "first_name"])
 
-        connection.add_index("testings", ["key"], :name => "key_idx", :unique => true)
-        connection.remove_index("testings", :name => "key_idx", :unique => true)
+        connection.add_index("testings", ["key"], name: "key_idx", unique: true)
+        connection.remove_index("testings", name: "key_idx", unique: true)
 
-        connection.add_index("testings", %w(last_name first_name administrator), :name => "named_admin")
-        connection.remove_index("testings", :name => "named_admin")
+        connection.add_index("testings", %w(last_name first_name administrator), name: "named_admin")
+        connection.remove_index("testings", name: "named_admin")
 
         # Selected adapters support index sort order
         if current_adapter?(:SQLite3Adapter, :Mysql2Adapter, :PostgreSQLAdapter)
-          connection.add_index("testings", ["last_name"], :order => {:last_name => :desc})
+          connection.add_index("testings", ["last_name"], order: { last_name: :desc })
           connection.remove_index("testings", ["last_name"])
-          connection.add_index("testings", ["last_name", "first_name"], :order => {:last_name => :desc})
+          connection.add_index("testings", ["last_name", "first_name"], order: { last_name: :desc })
           connection.remove_index("testings", ["last_name", "first_name"])
-          connection.add_index("testings", ["last_name", "first_name"], :order => {:last_name => :desc, :first_name => :asc})
+          connection.add_index("testings", ["last_name", "first_name"], order: { last_name: :desc, first_name: :asc })
           connection.remove_index("testings", ["last_name", "first_name"])
-          connection.add_index("testings", ["last_name", "first_name"], :order => :desc)
+          connection.add_index("testings", ["last_name", "first_name"], order: :desc)
           connection.remove_index("testings", ["last_name", "first_name"])
         end
       end
 
       if current_adapter?(:PostgreSQLAdapter)
         def test_add_partial_index
-          connection.add_index("testings", "last_name", :where => "first_name = 'john doe'")
+          connection.add_index("testings", "last_name", where: "first_name = 'john doe'")
           assert connection.index_exists?("testings", "last_name")
 
           connection.remove_index("testings", "last_name")
@@ -210,9 +209,8 @@ module ActiveRecord
 
       private
         def good_index_name
-          'x' * connection.allowed_index_name_length
+          "x" * connection.allowed_index_name_length
         end
-
     end
   end
 end
diff --git a/activerecord/test/cases/migration/logger_test.rb b/activerecord/test/cases/migration/logger_test.rb
index bf6e684887..28f4cc124b 100644
--- a/activerecord/test/cases/migration/logger_test.rb
+++ b/activerecord/test/cases/migration/logger_test.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require "cases/helper"
 
 module ActiveRecord
@@ -8,7 +10,7 @@ module ActiveRecord
 
       Migration = Struct.new(:name, :version) do
         def disable_ddl_transaction; false end
-        def migrate direction
+        def migrate(direction)
           # do nothing
         end
       end
@@ -26,7 +28,7 @@ module ActiveRecord
       def test_migration_should_be_run_without_logger
         previous_logger = ActiveRecord::Base.logger
         ActiveRecord::Base.logger = nil
-        migrations = [Migration.new('a', 1), Migration.new('b', 2), Migration.new('c', 3)]
+        migrations = [Migration.new("a", 1), Migration.new("b", 2), Migration.new("c", 3)]
         ActiveRecord::Migrator.new(:up, migrations).migrate
       ensure
         ActiveRecord::Base.logger = previous_logger
diff --git a/activerecord/test/cases/migration/pending_migrations_test.rb b/activerecord/test/cases/migration/pending_migrations_test.rb
index 4f5589f32a..d0066f68be 100644
--- a/activerecord/test/cases/migration/pending_migrations_test.rb
+++ b/activerecord/test/cases/migration/pending_migrations_test.rb
@@ -1,4 +1,6 @@
-require 'cases/helper'
+# frozen_string_literal: true
+
+require "cases/helper"
 
 module ActiveRecord
   class Migration
@@ -21,8 +23,6 @@ module ActiveRecord
       end
 
       def test_errors_if_pending
-        @connection.expect :supports_migrations?, true
-
         ActiveRecord::Migrator.stub :needs_migration?, true do
           assert_raise ActiveRecord::PendingMigrationError do
             @pending.call(nil)
@@ -31,22 +31,12 @@ module ActiveRecord
       end
 
       def test_checks_if_supported
-        @connection.expect :supports_migrations?, true
         @app.expect :call, nil, [:foo]
 
         ActiveRecord::Migrator.stub :needs_migration?, false do
           @pending.call(:foo)
         end
       end
-
-      def test_doesnt_check_if_unsupported
-        @connection.expect :supports_migrations?, false
-        @app.expect :call, nil, [:foo]
-
-        ActiveRecord::Migrator.stub :needs_migration?, true do
-          @pending.call(:foo)
-        end
-      end
     end
   end
 end
diff --git a/activerecord/test/cases/migration/references_foreign_key_test.rb b/activerecord/test/cases/migration/references_foreign_key_test.rb
index 9e19eb9f73..7a092103c7 100644
--- a/activerecord/test/cases/migration/references_foreign_key_test.rb
+++ b/activerecord/test/cases/migration/references_foreign_key_test.rb
@@ -1,216 +1,257 @@
-require 'cases/helper'
+# frozen_string_literal: true
 
-if ActiveRecord::Base.connection.supports_foreign_keys?
-module ActiveRecord
-  class Migration
-    class ReferencesForeignKeyTest < ActiveRecord::TestCase
-      setup do
-        @connection = ActiveRecord::Base.connection
-        @connection.create_table(:testing_parents, force: true)
-      end
+require "cases/helper"
 
-      teardown do
-        @connection.drop_table "testings", if_exists: true
-        @connection.drop_table "testing_parents", if_exists: true
-      end
+if ActiveRecord::Base.connection.supports_foreign_keys_in_create?
+  module ActiveRecord
+    class Migration
+      class ReferencesForeignKeyInCreateTest < ActiveRecord::TestCase
+        setup do
+          @connection = ActiveRecord::Base.connection
+          @connection.create_table(:testing_parents, force: true)
+        end
 
-      test "foreign keys can be created with the table" do
-        @connection.create_table :testings do |t|
-          t.references :testing_parent, foreign_key: true
+        teardown do
+          @connection.drop_table "testings", if_exists: true
+          @connection.drop_table "testing_parents", if_exists: true
         end
 
-        fk = @connection.foreign_keys("testings").first
-        assert_equal "testings", fk.from_table
-        assert_equal "testing_parents", fk.to_table
-      end
+        test "foreign keys can be created with the table" do
+          @connection.create_table :testings do |t|
+            t.references :testing_parent, foreign_key: true
+          end
 
-      test "no foreign key is created by default" do
-        @connection.create_table :testings do |t|
-          t.references :testing_parent
+          fk = @connection.foreign_keys("testings").first
+          assert_equal "testings", fk.from_table
+          assert_equal "testing_parents", fk.to_table
         end
 
-        assert_equal [], @connection.foreign_keys("testings")
-      end
-
-      test "foreign keys can be created in one query when index is not added" do
-        assert_queries(1) do
+        test "no foreign key is created by default" do
           @connection.create_table :testings do |t|
-            t.references :testing_parent, foreign_key: true, index: false
+            t.references :testing_parent
           end
-        end
-      end
 
-      test "options hash can be passed" do
-        @connection.change_table :testing_parents do |t|
-          t.integer :other_id
-          t.index :other_id, unique: true
+          assert_equal [], @connection.foreign_keys("testings")
         end
-        @connection.create_table :testings do |t|
-          t.references :testing_parent, foreign_key: { primary_key: :other_id }
+
+        test "foreign keys can be created in one query when index is not added" do
+          assert_queries(1) do
+            @connection.create_table :testings do |t|
+              t.references :testing_parent, foreign_key: true, index: false
+            end
+          end
         end
 
-        fk = @connection.foreign_keys("testings").find { |k| k.to_table == "testing_parents" }
-        assert_equal "other_id", fk.primary_key
-      end
+        test "options hash can be passed" do
+          @connection.change_table :testing_parents do |t|
+            t.references :other, index: { unique: true }
+          end
+          @connection.create_table :testings do |t|
+            t.references :testing_parent, foreign_key: { primary_key: :other_id }
+          end
 
-      test "to_table option can be passed" do
-        @connection.create_table :testings do |t|
-          t.references :parent, foreign_key: { to_table: :testing_parents }
+          fk = @connection.foreign_keys("testings").find { |k| k.to_table == "testing_parents" }
+          assert_equal "other_id", fk.primary_key
         end
-        fks = @connection.foreign_keys("testings")
-        assert_equal([["testings", "testing_parents", "parent_id"]],
-                     fks.map {|fk| [fk.from_table, fk.to_table, fk.column] })
-      end
 
-      test "foreign keys cannot be added to polymorphic relations when creating the table" do
-        @connection.create_table :testings do |t|
-          assert_raises(ArgumentError) do
-            t.references :testing_parent, polymorphic: true, foreign_key: true
+        test "to_table option can be passed" do
+          @connection.create_table :testings do |t|
+            t.references :parent, foreign_key: { to_table: :testing_parents }
           end
+          fks = @connection.foreign_keys("testings")
+          assert_equal([["testings", "testing_parents", "parent_id"]],
+                       fks.map { |fk| [fk.from_table, fk.to_table, fk.column] })
         end
       end
+    end
+  end
+end
 
-      test "foreign keys can be created while changing the table" do
-        @connection.create_table :testings
-        @connection.change_table :testings do |t|
-          t.references :testing_parent, foreign_key: true
+if ActiveRecord::Base.connection.supports_foreign_keys?
+  module ActiveRecord
+    class Migration
+      class ReferencesForeignKeyTest < ActiveRecord::TestCase
+        setup do
+          @connection = ActiveRecord::Base.connection
+          @connection.create_table(:testing_parents, force: true)
         end
 
-        fk = @connection.foreign_keys("testings").first
-        assert_equal "testings", fk.from_table
-        assert_equal "testing_parents", fk.to_table
-      end
+        teardown do
+          @connection.drop_table "testings", if_exists: true
+          @connection.drop_table "testing_parents", if_exists: true
+        end
 
-      test "foreign keys are not added by default when changing the table" do
-        @connection.create_table :testings
-        @connection.change_table :testings do |t|
-          t.references :testing_parent
+        test "foreign keys cannot be added to polymorphic relations when creating the table" do
+          @connection.create_table :testings do |t|
+            assert_raises(ArgumentError) do
+              t.references :testing_parent, polymorphic: true, foreign_key: true
+            end
+          end
         end
 
-        assert_equal [], @connection.foreign_keys("testings")
-      end
+        test "foreign keys can be created while changing the table" do
+          @connection.create_table :testings
+          @connection.change_table :testings do |t|
+            t.references :testing_parent, foreign_key: true
+          end
 
-      test "foreign keys accept options when changing the table" do
-        @connection.change_table :testing_parents do |t|
-          t.integer :other_id
-          t.index :other_id, unique: true
-        end
-        @connection.create_table :testings
-        @connection.change_table :testings do |t|
-          t.references :testing_parent, foreign_key: { primary_key: :other_id }
+          fk = @connection.foreign_keys("testings").first
+          assert_equal "testings", fk.from_table
+          assert_equal "testing_parents", fk.to_table
         end
 
-        fk = @connection.foreign_keys("testings").find { |k| k.to_table == "testing_parents" }
-        assert_equal "other_id", fk.primary_key
-      end
+        test "foreign keys are not added by default when changing the table" do
+          @connection.create_table :testings
+          @connection.change_table :testings do |t|
+            t.references :testing_parent
+          end
 
-      test "foreign keys cannot be added to polymorphic relations when changing the table" do
-        @connection.create_table :testings
-        @connection.change_table :testings do |t|
-          assert_raises(ArgumentError) do
-            t.references :testing_parent, polymorphic: true, foreign_key: true
+          assert_equal [], @connection.foreign_keys("testings")
+        end
+
+        test "foreign keys accept options when changing the table" do
+          @connection.change_table :testing_parents do |t|
+            t.references :other, index: { unique: true }
           end
+          @connection.create_table :testings
+          @connection.change_table :testings do |t|
+            t.references :testing_parent, foreign_key: { primary_key: :other_id }
+          end
+
+          fk = @connection.foreign_keys("testings").find { |k| k.to_table == "testing_parents" }
+          assert_equal "other_id", fk.primary_key
         end
-      end
 
-      test "foreign key column can be removed" do
-        @connection.create_table :testings do |t|
-          t.references :testing_parent, index: true, foreign_key: true
+        test "foreign keys cannot be added to polymorphic relations when changing the table" do
+          @connection.create_table :testings
+          @connection.change_table :testings do |t|
+            assert_raises(ArgumentError) do
+              t.references :testing_parent, polymorphic: true, foreign_key: true
+            end
+          end
         end
 
-        assert_difference "@connection.foreign_keys('testings').size", -1 do
-          @connection.remove_reference :testings, :testing_parent, foreign_key: true
+        test "foreign key column can be removed" do
+          @connection.create_table :testings do |t|
+            t.references :testing_parent, index: true, foreign_key: true
+          end
+
+          assert_difference "@connection.foreign_keys('testings').size", -1 do
+            @connection.remove_reference :testings, :testing_parent, foreign_key: true
+          end
         end
-      end
 
-      test "foreign key methods respect pluralize_table_names" do
-        begin
-          original_pluralize_table_names = ActiveRecord::Base.pluralize_table_names
-          ActiveRecord::Base.pluralize_table_names = false
-          @connection.create_table :testing
-          @connection.change_table :testing_parents do |t|
-            t.references :testing, foreign_key: true
+        test "removing column removes foreign key" do
+          @connection.create_table :testings do |t|
+            t.references :testing_parent, index: true, foreign_key: true
           end
 
-          fk = @connection.foreign_keys("testing_parents").first
-          assert_equal "testing_parents", fk.from_table
-          assert_equal "testing", fk.to_table
+          assert_difference "@connection.foreign_keys('testings').size", -1 do
+            @connection.remove_column :testings, :testing_parent_id
+          end
+        end
 
-          assert_difference "@connection.foreign_keys('testing_parents').size", -1 do
-            @connection.remove_reference :testing_parents, :testing, foreign_key: true
+        test "foreign key methods respect pluralize_table_names" do
+          begin
+            original_pluralize_table_names = ActiveRecord::Base.pluralize_table_names
+            ActiveRecord::Base.pluralize_table_names = false
+            @connection.create_table :testing
+            @connection.change_table :testing_parents do |t|
+              t.references :testing, foreign_key: true
+            end
+
+            fk = @connection.foreign_keys("testing_parents").first
+            assert_equal "testing_parents", fk.from_table
+            assert_equal "testing", fk.to_table
+
+            assert_difference "@connection.foreign_keys('testing_parents').size", -1 do
+              @connection.remove_reference :testing_parents, :testing, foreign_key: true
+            end
+          ensure
+            ActiveRecord::Base.pluralize_table_names = original_pluralize_table_names
+            @connection.drop_table "testing", if_exists: true
           end
-        ensure
-          ActiveRecord::Base.pluralize_table_names = original_pluralize_table_names
-          @connection.drop_table "testing", if_exists: true
         end
-      end
 
-      class CreateDogsMigration < ActiveRecord::Migration::Current
-        def change
-          create_table :dog_owners
+        class CreateDogsMigration < ActiveRecord::Migration::Current
+          def change
+            create_table :dog_owners
 
-          create_table :dogs do |t|
-            t.references :dog_owner, foreign_key: true
+            create_table :dogs do |t|
+              t.references :dog_owner, foreign_key: true
+            end
           end
         end
-      end
 
-      def test_references_foreign_key_with_prefix
-        ActiveRecord::Base.table_name_prefix = 'p_'
-        migration = CreateDogsMigration.new
-        silence_stream($stdout) { migration.migrate(:up) }
-        assert_equal 1, @connection.foreign_keys("p_dogs").size
-      ensure
-        silence_stream($stdout) { migration.migrate(:down) }
-        ActiveRecord::Base.table_name_prefix = nil
-      end
+        def test_references_foreign_key_with_prefix
+          ActiveRecord::Base.table_name_prefix = "p_"
+          migration = CreateDogsMigration.new
+          silence_stream($stdout) { migration.migrate(:up) }
+          assert_equal 1, @connection.foreign_keys("p_dogs").size
+        ensure
+          silence_stream($stdout) { migration.migrate(:down) }
+          ActiveRecord::Base.table_name_prefix = nil
+        end
 
-      def test_references_foreign_key_with_suffix
-        ActiveRecord::Base.table_name_suffix = '_s'
-        migration = CreateDogsMigration.new
-        silence_stream($stdout) { migration.migrate(:up) }
-        assert_equal 1, @connection.foreign_keys("dogs_s").size
-      ensure
-        silence_stream($stdout) { migration.migrate(:down) }
-        ActiveRecord::Base.table_name_suffix = nil
-      end
+        def test_references_foreign_key_with_suffix
+          ActiveRecord::Base.table_name_suffix = "_s"
+          migration = CreateDogsMigration.new
+          silence_stream($stdout) { migration.migrate(:up) }
+          assert_equal 1, @connection.foreign_keys("dogs_s").size
+        ensure
+          silence_stream($stdout) { migration.migrate(:down) }
+          ActiveRecord::Base.table_name_suffix = nil
+        end
 
-      test "multiple foreign keys can be added to the same table" do
-        @connection.create_table :testings do |t|
-          t.integer :col_1
-          t.integer :col_2
+        test "multiple foreign keys can be added to the same table" do
+          @connection.create_table :testings do |t|
+            t.references :parent1, foreign_key: { to_table: :testing_parents }
+            t.references :parent2, foreign_key: { to_table: :testing_parents }
+          end
 
-          t.foreign_key :testing_parents, column: :col_1
-          t.foreign_key :testing_parents, column: :col_2
+          fks = @connection.foreign_keys("testings").sort_by(&:column)
+
+          fk_definitions = fks.map { |fk| [fk.from_table, fk.to_table, fk.column] }
+          assert_equal([["testings", "testing_parents", "parent1_id"],
+                        ["testings", "testing_parents", "parent2_id"]], fk_definitions)
         end
 
-        fks = @connection.foreign_keys("testings")
+        test "multiple foreign keys can be removed to the selected one" do
+          @connection.create_table :testings do |t|
+            t.references :parent1, foreign_key: { to_table: :testing_parents }
+            t.references :parent2, foreign_key: { to_table: :testing_parents }
+          end
+
+          assert_difference "@connection.foreign_keys('testings').size", -1 do
+            @connection.remove_reference :testings, :parent1, foreign_key: { to_table: :testing_parents }
+          end
 
-        fk_definitions = fks.map {|fk| [fk.from_table, fk.to_table, fk.column] }
-        assert_equal([["testings", "testing_parents", "col_1"],
-                      ["testings", "testing_parents", "col_2"]], fk_definitions)
+          fks = @connection.foreign_keys("testings").sort_by(&:column)
+
+          fk_definitions = fks.map { |fk| [fk.from_table, fk.to_table, fk.column] }
+          assert_equal([["testings", "testing_parents", "parent2_id"]], fk_definitions)
+        end
       end
     end
   end
-end
 else
-class ReferencesWithoutForeignKeySupportTest < ActiveRecord::TestCase
-  setup do
-    @connection = ActiveRecord::Base.connection
-    @connection.create_table(:testing_parents, force: true)
-  end
-
-  teardown do
-    @connection.drop_table("testings", if_exists: true)
-    @connection.drop_table("testing_parents", if_exists: true)
-  end
+  class ReferencesWithoutForeignKeySupportTest < ActiveRecord::TestCase
+    setup do
+      @connection = ActiveRecord::Base.connection
+      @connection.create_table(:testing_parents, force: true)
+    end
 
-  test "ignores foreign keys defined with the table" do
-    @connection.create_table :testings do |t|
-      t.references :testing_parent, foreign_key: true
+    teardown do
+      @connection.drop_table("testings", if_exists: true)
+      @connection.drop_table("testing_parents", if_exists: true)
     end
 
-    assert_includes @connection.data_sources, "testings"
+    test "ignores foreign keys defined with the table" do
+      @connection.create_table :testings do |t|
+        t.references :testing_parent, foreign_key: true
+      end
+
+      assert_includes @connection.data_sources, "testings"
+    end
   end
 end
-end
diff --git a/activerecord/test/cases/migration/references_index_test.rb b/activerecord/test/cases/migration/references_index_test.rb
index a9a7f0f4c4..e41377d817 100644
--- a/activerecord/test/cases/migration/references_index_test.rb
+++ b/activerecord/test/cases/migration/references_index_test.rb
@@ -1,4 +1,6 @@
-require 'cases/helper'
+# frozen_string_literal: true
+
+require "cases/helper"
 
 module ActiveRecord
   class Migration
@@ -17,10 +19,10 @@ module ActiveRecord
 
       def test_creates_index
         connection.create_table table_name do |t|
-          t.references :foo, :index => true
+          t.references :foo, index: true
         end
 
-        assert connection.index_exists?(table_name, :foo_id, :name => :index_testings_on_foo_id)
+        assert connection.index_exists?(table_name, :foo_id, name: :index_testings_on_foo_id)
       end
 
       def test_creates_index_by_default_even_if_index_option_is_not_passed
@@ -28,31 +30,31 @@ module ActiveRecord
           t.references :foo
         end
 
-        assert connection.index_exists?(table_name, :foo_id, :name => :index_testings_on_foo_id)
+        assert connection.index_exists?(table_name, :foo_id, name: :index_testings_on_foo_id)
       end
 
       def test_does_not_create_index_explicit
         connection.create_table table_name do |t|
-          t.references :foo, :index => false
+          t.references :foo, index: false
         end
 
-        assert_not connection.index_exists?(table_name, :foo_id, :name => :index_testings_on_foo_id)
+        assert_not connection.index_exists?(table_name, :foo_id, name: :index_testings_on_foo_id)
       end
 
       def test_creates_index_with_options
         connection.create_table table_name do |t|
-          t.references :foo, :index => {:name => :index_testings_on_yo_momma}
-          t.references :bar, :index => {:unique => true}
+          t.references :foo, index: { name: :index_testings_on_yo_momma }
+          t.references :bar, index: { unique: true }
         end
 
-        assert connection.index_exists?(table_name, :foo_id, :name => :index_testings_on_yo_momma)
-        assert connection.index_exists?(table_name, :bar_id, :name => :index_testings_on_bar_id, :unique => true)
+        assert connection.index_exists?(table_name, :foo_id, name: :index_testings_on_yo_momma)
+        assert connection.index_exists?(table_name, :bar_id, name: :index_testings_on_bar_id, unique: true)
       end
 
       unless current_adapter? :OracleAdapter
         def test_creates_polymorphic_index
           connection.create_table table_name do |t|
-            t.references :foo, :polymorphic => true, :index => true
+            t.references :foo, polymorphic: true, index: true
           end
 
           assert connection.index_exists?(table_name, [:foo_type, :foo_id], name: :index_testings_on_foo_type_and_foo_id)
@@ -62,10 +64,10 @@ module ActiveRecord
       def test_creates_index_for_existing_table
         connection.create_table table_name
         connection.change_table table_name do |t|
-          t.references :foo, :index => true
+          t.references :foo, index: true
         end
 
-        assert connection.index_exists?(table_name, :foo_id, :name => :index_testings_on_foo_id)
+        assert connection.index_exists?(table_name, :foo_id, name: :index_testings_on_foo_id)
       end
 
       def test_creates_index_for_existing_table_even_if_index_option_is_not_passed
@@ -74,23 +76,23 @@ module ActiveRecord
           t.references :foo
         end
 
-        assert connection.index_exists?(table_name, :foo_id, :name => :index_testings_on_foo_id)
+        assert connection.index_exists?(table_name, :foo_id, name: :index_testings_on_foo_id)
       end
 
       def test_does_not_create_index_for_existing_table_explicit
         connection.create_table table_name
         connection.change_table table_name do |t|
-          t.references :foo, :index => false
+          t.references :foo, index: false
         end
 
-        assert_not connection.index_exists?(table_name, :foo_id, :name => :index_testings_on_foo_id)
+        assert_not connection.index_exists?(table_name, :foo_id, name: :index_testings_on_foo_id)
       end
 
       unless current_adapter? :OracleAdapter
         def test_creates_polymorphic_index_for_existing_table
           connection.create_table table_name
           connection.change_table table_name do |t|
-            t.references :foo, :polymorphic => true, :index => true
+            t.references :foo, polymorphic: true, index: true
           end
 
           assert connection.index_exists?(table_name, [:foo_type, :foo_id], name: :index_testings_on_foo_type_and_foo_id)
diff --git a/activerecord/test/cases/migration/references_statements_test.rb b/activerecord/test/cases/migration/references_statements_test.rb
index 70c64f3e71..769241ba12 100644
--- a/activerecord/test/cases/migration/references_statements_test.rb
+++ b/activerecord/test/cases/migration/references_statements_test.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require "cases/migration/helper"
 
 module ActiveRecord
@@ -35,7 +37,7 @@ module ActiveRecord
         assert_not index_exists?(table_name, :user_id)
       end
 
-      def test_create_reference_id_index_even_if_index_option_is_passed
+      def test_create_reference_id_index_even_if_index_option_is_not_passed
         add_reference table_name, :user
         assert index_exists?(table_name, :user_id)
       end
@@ -46,18 +48,33 @@ module ActiveRecord
       end
 
       def test_creates_reference_type_column_with_default
-        add_reference table_name, :taggable, polymorphic: { default: 'Photo' }, index: true
-        assert column_exists?(table_name, :taggable_type, :string, default: 'Photo')
+        add_reference table_name, :taggable, polymorphic: { default: "Photo" }, index: true
+        assert column_exists?(table_name, :taggable_type, :string, default: "Photo")
+      end
+
+      def test_creates_reference_type_column_with_not_null
+        connection.create_table table_name, force: true do |t|
+          t.references :taggable, null: false, polymorphic: true
+        end
+        assert column_exists?(table_name, :taggable_id, :integer, null: false)
+        assert column_exists?(table_name, :taggable_type, :string, null: false)
+      end
+
+      def test_does_not_share_options_with_reference_type_column
+        add_reference table_name, :taggable, type: :integer, limit: 2, polymorphic: true
+        assert column_exists?(table_name, :taggable_id, :integer, limit: 2)
+        assert column_exists?(table_name, :taggable_type, :string)
+        assert_not column_exists?(table_name, :taggable_type, :string, limit: 2)
       end
 
       def test_creates_named_index
-        add_reference table_name, :tag, index: { name: 'index_taggings_on_tag_id' }
-        assert index_exists?(table_name, :tag_id, name: 'index_taggings_on_tag_id')
+        add_reference table_name, :tag, index: { name: "index_taggings_on_tag_id" }
+        assert index_exists?(table_name, :tag_id, name: "index_taggings_on_tag_id")
       end
 
       def test_creates_named_unique_index
-        add_reference table_name, :tag, index: { name: 'index_taggings_on_tag_id', unique: true }
-        assert index_exists?(table_name, :tag_id, name: 'index_taggings_on_tag_id', unique: true )
+        add_reference table_name, :tag, index: { name: "index_taggings_on_tag_id", unique: true }
+        assert index_exists?(table_name, :tag_id, name: "index_taggings_on_tag_id", unique: true)
       end
 
       def test_creates_reference_id_with_specified_type
@@ -110,12 +127,12 @@ module ActiveRecord
 
       private
 
-      def with_polymorphic_column
-        add_column table_name, :supplier_type, :string
-        add_index table_name, [:supplier_id, :supplier_type]
+        def with_polymorphic_column
+          add_column table_name, :supplier_type, :string
+          add_index table_name, [:supplier_id, :supplier_type]
 
-        yield
-      end
+          yield
+        end
     end
   end
 end
diff --git a/activerecord/test/cases/migration/rename_table_test.rb b/activerecord/test/cases/migration/rename_table_test.rb
index b926a92849..dfce266253 100644
--- a/activerecord/test/cases/migration/rename_table_test.rb
+++ b/activerecord/test/cases/migration/rename_table_test.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require "cases/migration/helper"
 
 module ActiveRecord
@@ -9,13 +11,13 @@ module ActiveRecord
 
       def setup
         super
-        add_column 'test_models', :url, :string
-        remove_column 'test_models', :created_at
-        remove_column 'test_models', :updated_at
+        add_column "test_models", :url, :string
+        remove_column "test_models", :created_at
+        remove_column "test_models", :updated_at
       end
 
       def teardown
-        ActiveSupport::Deprecation.silence { rename_table :octopi, :test_models if connection.table_exists? :octopi }
+        rename_table :octopi, :test_models if connection.table_exists? :octopi
         super
       end
 
@@ -31,7 +33,7 @@ module ActiveRecord
 
           # Using explicit id in insert for compatibility across all databases
           connection.execute "INSERT INTO 'references' (url, created_at, updated_at) VALUES ('http://rubyonrails.com', 0, 0)"
-          assert_equal 'http://rubyonrails.com', connection.select_value("SELECT url FROM 'references' WHERE id=1")
+          assert_equal "http://rubyonrails.com", connection.select_value("SELECT url FROM 'references' WHERE id=1")
         ensure
           return unless renamed
           connection.rename_table :references, :test_models
@@ -45,7 +47,7 @@ module ActiveRecord
 
           connection.execute "INSERT INTO octopi (#{connection.quote_column_name('id')}, #{connection.quote_column_name('url')}) VALUES (1, 'http://www.foreverflying.com/octopus-black7.jpg')"
 
-          assert_equal 'http://www.foreverflying.com/octopus-black7.jpg', connection.select_value("SELECT url FROM octopi WHERE id=1")
+          assert_equal "http://www.foreverflying.com/octopus-black7.jpg", connection.select_value("SELECT url FROM octopi WHERE id=1")
         end
 
         def test_rename_table_with_an_index
@@ -55,18 +57,18 @@ module ActiveRecord
 
           connection.execute "INSERT INTO octopi (#{connection.quote_column_name('id')}, #{connection.quote_column_name('url')}) VALUES (1, 'http://www.foreverflying.com/octopus-black7.jpg')"
 
-          assert_equal 'http://www.foreverflying.com/octopus-black7.jpg', connection.select_value("SELECT url FROM octopi WHERE id=1")
+          assert_equal "http://www.foreverflying.com/octopus-black7.jpg", connection.select_value("SELECT url FROM octopi WHERE id=1")
           index = connection.indexes(:octopi).first
-          assert index.columns.include?("url")
-          assert_equal 'index_octopi_on_url', index.name
+          assert_includes index.columns, "url"
+          assert_equal "index_octopi_on_url", index.name
         end
 
         def test_rename_table_does_not_rename_custom_named_index
-          add_index :test_models, :url, name: 'special_url_idx'
+          add_index :test_models, :url, name: "special_url_idx"
 
           rename_table :test_models, :octopi
 
-          assert_equal ['special_url_idx'], connection.indexes(:octopi).map(&:name)
+          assert_equal ["special_url_idx"], connection.indexes(:octopi).map(&:name)
         end
       end
 
@@ -74,15 +76,38 @@ module ActiveRecord
         def test_rename_table_for_postgresql_should_also_rename_default_sequence
           rename_table :test_models, :octopi
 
-          pk, seq = connection.pk_and_sequence_for('octopi')
+          pk, seq = connection.pk_and_sequence_for("octopi")
 
           assert_equal ConnectionAdapters::PostgreSQL::Name.new("public", "octopi_#{pk}_seq"), seq
         end
 
+        def test_renaming_table_renames_primary_key
+          connection.create_table :cats, id: :uuid, default: "uuid_generate_v4()"
+          rename_table :cats, :felines
+
+          assert connection.table_exists? :felines
+          refute connection.table_exists? :cats
+
+          primary_key_name = connection.select_values(<<-SQL.strip_heredoc, "SCHEMA")[0]
+            SELECT c.relname
+              FROM pg_class c
+              JOIN pg_index i
+                ON c.oid = i.indexrelid
+             WHERE i.indisprimary
+               AND i.indrelid = 'felines'::regclass
+          SQL
+
+          assert_equal "felines_pkey", primary_key_name
+        ensure
+          connection.drop_table :cats, if_exists: true
+          connection.drop_table :felines, if_exists: true
+        end
+
         def test_renaming_table_doesnt_attempt_to_rename_non_existent_sequences
-          connection.create_table :cats, id: :uuid
+          connection.create_table :cats, id: :uuid, default: "uuid_generate_v4()"
           assert_nothing_raised { rename_table :cats, :felines }
-          ActiveSupport::Deprecation.silence { assert connection.table_exists? :felines }
+          assert connection.table_exists? :felines
+          refute connection.table_exists? :cats
         ensure
           connection.drop_table :cats, if_exists: true
           connection.drop_table :felines, if_exists: true
diff --git a/activerecord/test/cases/migration_test.rb b/activerecord/test/cases/migration_test.rb
index 36b6662820..b18af2ab55 100644
--- a/activerecord/test/cases/migration_test.rb
+++ b/activerecord/test/cases/migration_test.rb
@@ -1,12 +1,14 @@
-require 'cases/helper'
-require 'cases/migration/helper'
-require 'bigdecimal/util'
-require 'concurrent/atomic/count_down_latch'
+# frozen_string_literal: true
 
-require 'models/person'
-require 'models/topic'
-require 'models/developer'
-require 'models/computer'
+require "cases/helper"
+require "cases/migration/helper"
+require "bigdecimal/util"
+require "concurrent/atomic/count_down_latch"
+
+require "models/person"
+require "models/topic"
+require "models/developer"
+require "models/computer"
 
 require MIGRATIONS_ROOT + "/valid/2_we_need_reminders"
 require MIGRATIONS_ROOT + "/rename/1_we_need_things"
@@ -43,10 +45,10 @@ class MigrationTest < ActiveRecord::TestCase
     ActiveRecord::Base.table_name_prefix = ""
     ActiveRecord::Base.table_name_suffix = ""
 
-    ActiveRecord::Base.connection.initialize_schema_migrations_table
-    ActiveRecord::Base.connection.execute "DELETE FROM #{ActiveRecord::Migrator.schema_migrations_table_name}"
+    ActiveRecord::SchemaMigration.create_table
+    ActiveRecord::SchemaMigration.delete_all
 
-    %w(things awesome_things prefix_things_suffix p_awesome_things_s ).each do |table|
+    %w(things awesome_things prefix_things_suffix p_awesome_things_s).each do |table|
       Thing.connection.drop_table(table) rescue nil
     end
     Thing.reset_column_information
@@ -59,7 +61,7 @@ class MigrationTest < ActiveRecord::TestCase
 
     %w(last_name key bio age height wealth birthday favorite_day
        moment_of_truth male administrator funny).each do |column|
-      Person.connection.remove_column('people', column) rescue nil
+      Person.connection.remove_column("people", column) rescue nil
     end
     Person.connection.remove_column("people", "first_name") rescue nil
     Person.connection.remove_column("people", "middle_name") rescue nil
@@ -93,7 +95,7 @@ class MigrationTest < ActiveRecord::TestCase
   end
 
   def test_migration_detection_without_schema_migration_table
-    ActiveRecord::Base.connection.drop_table 'schema_migrations', if_exists: true
+    ActiveRecord::Base.connection.drop_table "schema_migrations", if_exists: true
 
     migrations_path = MIGRATIONS_ROOT + "/valid"
     old_path = ActiveRecord::Migrator.migrations_paths
@@ -128,7 +130,7 @@ class MigrationTest < ActiveRecord::TestCase
 
     assert_not_equal temp_conn, Person.connection
 
-    temp_conn.create_table :testings2, :force => true do |t|
+    temp_conn.create_table :testings2, force: true do |t|
       t.column :foo, :string
     end
   ensure
@@ -160,11 +162,11 @@ class MigrationTest < ActiveRecord::TestCase
     BigNumber.reset_column_information
 
     assert BigNumber.create(
-      :bank_balance => 1586.43,
-      :big_bank_balance => BigDecimal("1000234000567.95"),
-      :world_population => 6000000000,
-      :my_house_population => 3,
-      :value_of_e => BigDecimal("2.7182818284590452353602875")
+      bank_balance: 1586.43,
+      big_bank_balance: BigDecimal("1000234000567.95"),
+      world_population: 6000000000,
+      my_house_population: 3,
+      value_of_e: BigDecimal("2.7182818284590452353602875")
     )
 
     b = BigNumber.first
@@ -248,22 +250,22 @@ class MigrationTest < ActiveRecord::TestCase
 
   def test_instance_based_migration_up
     migration = MockMigration.new
-    assert !migration.went_up, 'have not gone up'
-    assert !migration.went_down, 'have not gone down'
+    assert !migration.went_up, "have not gone up"
+    assert !migration.went_down, "have not gone down"
 
     migration.migrate :up
-    assert migration.went_up, 'have gone up'
-    assert !migration.went_down, 'have not gone down'
+    assert migration.went_up, "have gone up"
+    assert !migration.went_down, "have not gone down"
   end
 
   def test_instance_based_migration_down
     migration = MockMigration.new
-    assert !migration.went_up, 'have not gone up'
-    assert !migration.went_down, 'have not gone down'
+    assert !migration.went_up, "have not gone up"
+    assert !migration.went_down, "have not gone down"
 
     migration.migrate :down
-    assert !migration.went_up, 'have gone up'
-    assert migration.went_down, 'have not gone down'
+    assert !migration.went_up, "have gone up"
+    assert migration.went_down, "have not gone down"
   end
 
   if ActiveRecord::Base.connection.supports_ddl_transactions?
@@ -274,7 +276,7 @@ class MigrationTest < ActiveRecord::TestCase
         def version; 100 end
         def migrate(x)
           add_column "people", "last_name", :string
-          raise 'Something broke'
+          raise "Something broke"
         end
       }.new
 
@@ -295,7 +297,7 @@ class MigrationTest < ActiveRecord::TestCase
         def version; 100 end
         def migrate(x)
           add_column "people", "last_name", :string
-          raise 'Something broke'
+          raise "Something broke"
         end
       }.new
 
@@ -313,12 +315,12 @@ class MigrationTest < ActiveRecord::TestCase
       assert_no_column Person, :last_name
 
       migration = Class.new(ActiveRecord::Migration::Current) {
-        self.disable_ddl_transaction!
+        disable_ddl_transaction!
 
         def version; 101 end
         def migrate(x)
           add_column "people", "last_name", :string
-          raise 'Something broke'
+          raise "Something broke"
         end
       }.new
 
@@ -330,27 +332,27 @@ class MigrationTest < ActiveRecord::TestCase
         "without ddl transactions, the Migrator should not rollback on error but it did."
     ensure
       Person.reset_column_information
-      if Person.column_names.include?('last_name')
-        Person.connection.remove_column('people', 'last_name')
+      if Person.column_names.include?("last_name")
+        Person.connection.remove_column("people", "last_name")
       end
     end
   end
 
   def test_schema_migrations_table_name
-    original_schema_migrations_table_name = ActiveRecord::Migrator.schema_migrations_table_name
+    original_schema_migrations_table_name = ActiveRecord::Base.schema_migrations_table_name
 
-    assert_equal "schema_migrations", ActiveRecord::Migrator.schema_migrations_table_name
+    assert_equal "schema_migrations", ActiveRecord::SchemaMigration.table_name
     ActiveRecord::Base.table_name_prefix = "prefix_"
     ActiveRecord::Base.table_name_suffix = "_suffix"
     Reminder.reset_table_name
-    assert_equal "prefix_schema_migrations_suffix", ActiveRecord::Migrator.schema_migrations_table_name
+    assert_equal "prefix_schema_migrations_suffix", ActiveRecord::SchemaMigration.table_name
     ActiveRecord::Base.schema_migrations_table_name = "changed"
     Reminder.reset_table_name
-    assert_equal "prefix_changed_suffix", ActiveRecord::Migrator.schema_migrations_table_name
+    assert_equal "prefix_changed_suffix", ActiveRecord::SchemaMigration.table_name
     ActiveRecord::Base.table_name_prefix = ""
     ActiveRecord::Base.table_name_suffix = ""
     Reminder.reset_table_name
-    assert_equal "changed", ActiveRecord::Migrator.schema_migrations_table_name
+    assert_equal "changed", ActiveRecord::SchemaMigration.table_name
   ensure
     ActiveRecord::Base.schema_migrations_table_name = original_schema_migrations_table_name
     Reminder.reset_table_name
@@ -388,7 +390,7 @@ class MigrationTest < ActiveRecord::TestCase
     original_rails_env  = ENV["RAILS_ENV"]
     original_rack_env   = ENV["RACK_ENV"]
     ENV["RAILS_ENV"]    = ENV["RACK_ENV"] = "foofoo"
-    new_env     = ActiveRecord::ConnectionHandling::DEFAULT_ENV.call
+    new_env = ActiveRecord::ConnectionHandling::DEFAULT_ENV.call
 
     refute_equal current_env, new_env
 
@@ -399,71 +401,30 @@ class MigrationTest < ActiveRecord::TestCase
     ActiveRecord::Migrator.migrations_paths = old_path
     ENV["RAILS_ENV"] = original_rails_env
     ENV["RACK_ENV"]  = original_rack_env
-  end
-
-
-  def test_migration_sets_internal_metadata_even_when_fully_migrated
-    current_env     = ActiveRecord::ConnectionHandling::DEFAULT_ENV.call
-    migrations_path = MIGRATIONS_ROOT + "/valid"
-    old_path        = ActiveRecord::Migrator.migrations_paths
-    ActiveRecord::Migrator.migrations_paths = migrations_path
-
     ActiveRecord::Migrator.up(migrations_path)
-    assert_equal current_env, ActiveRecord::InternalMetadata[:environment]
-
-    original_rails_env  = ENV["RAILS_ENV"]
-    original_rack_env   = ENV["RACK_ENV"]
-    ENV["RAILS_ENV"]    = ENV["RACK_ENV"] = "foofoo"
-    new_env     = ActiveRecord::ConnectionHandling::DEFAULT_ENV.call
-
-    refute_equal current_env, new_env
-
-    sleep 1 # mysql by default does not store fractional seconds in the database
-
-    ActiveRecord::Migrator.up(migrations_path)
-    assert_equal new_env, ActiveRecord::InternalMetadata[:environment]
-  ensure
-    ActiveRecord::Migrator.migrations_paths = old_path
-    ENV["RAILS_ENV"] = original_rails_env
-    ENV["RACK_ENV"]  = original_rack_env
   end
 
   def test_internal_metadata_stores_environment_when_other_data_exists
     ActiveRecord::InternalMetadata.delete_all
-    ActiveRecord::InternalMetadata[:foo]  = 'bar'
+    ActiveRecord::InternalMetadata[:foo] = "bar"
 
     current_env     = ActiveRecord::ConnectionHandling::DEFAULT_ENV.call
     migrations_path = MIGRATIONS_ROOT + "/valid"
     old_path        = ActiveRecord::Migrator.migrations_paths
     ActiveRecord::Migrator.migrations_paths = migrations_path
 
-    current_env     = ActiveRecord::ConnectionHandling::DEFAULT_ENV.call
+    current_env = ActiveRecord::ConnectionHandling::DEFAULT_ENV.call
     ActiveRecord::Migrator.up(migrations_path)
     assert_equal current_env, ActiveRecord::InternalMetadata[:environment]
-    assert_equal 'bar', ActiveRecord::InternalMetadata[:foo]
+    assert_equal "bar", ActiveRecord::InternalMetadata[:foo]
   ensure
     ActiveRecord::Migrator.migrations_paths = old_path
   end
 
-  def test_rename_internal_metadata_table
-    original_internal_metadata_table_name = ActiveRecord::Base.internal_metadata_table_name
-
-    ActiveRecord::Base.internal_metadata_table_name = "active_record_internal_metadatas"
-    Reminder.reset_table_name
-
-    ActiveRecord::Base.internal_metadata_table_name = original_internal_metadata_table_name
-    Reminder.reset_table_name
-
-    assert_equal "ar_internal_metadata", ActiveRecord::InternalMetadata.table_name
-  ensure
-    ActiveRecord::Base.internal_metadata_table_name = original_internal_metadata_table_name
-    Reminder.reset_table_name
-  end
-
   def test_proper_table_name_on_migration
     reminder_class = new_isolated_reminder_class
     migration = ActiveRecord::Migration.new
-    assert_equal "table", migration.proper_table_name('table')
+    assert_equal "table", migration.proper_table_name("table")
     assert_equal "table", migration.proper_table_name(:table)
     assert_equal "reminders", migration.proper_table_name(reminder_class)
     reminder_class.reset_table_name
@@ -472,26 +433,26 @@ class MigrationTest < ActiveRecord::TestCase
     # Use the model's own prefix/suffix if a model is given
     ActiveRecord::Base.table_name_prefix = "ARprefix_"
     ActiveRecord::Base.table_name_suffix = "_ARsuffix"
-    reminder_class.table_name_prefix = 'prefix_'
-    reminder_class.table_name_suffix = '_suffix'
+    reminder_class.table_name_prefix = "prefix_"
+    reminder_class.table_name_suffix = "_suffix"
     reminder_class.reset_table_name
     assert_equal "prefix_reminders_suffix", migration.proper_table_name(reminder_class)
-    reminder_class.table_name_prefix = ''
-    reminder_class.table_name_suffix = ''
+    reminder_class.table_name_prefix = ""
+    reminder_class.table_name_suffix = ""
     reminder_class.reset_table_name
 
     # Use AR::Base's prefix/suffix if string or symbol is given
     ActiveRecord::Base.table_name_prefix = "prefix_"
     ActiveRecord::Base.table_name_suffix = "_suffix"
     reminder_class.reset_table_name
-    assert_equal "prefix_table_suffix", migration.proper_table_name('table', migration.table_name_options)
+    assert_equal "prefix_table_suffix", migration.proper_table_name("table", migration.table_name_options)
     assert_equal "prefix_table_suffix", migration.proper_table_name(:table, migration.table_name_options)
   end
 
   def test_rename_table_with_prefix_and_suffix
     assert !Thing.table_exists?
-    ActiveRecord::Base.table_name_prefix = 'p_'
-    ActiveRecord::Base.table_name_suffix = '_s'
+    ActiveRecord::Base.table_name_prefix = "p_"
+    ActiveRecord::Base.table_name_suffix = "_s"
     Thing.reset_table_name
     Thing.reset_sequence_name
     WeNeedThings.up
@@ -511,8 +472,8 @@ class MigrationTest < ActiveRecord::TestCase
 
   def test_add_drop_table_with_prefix_and_suffix
     assert !Reminder.table_exists?
-    ActiveRecord::Base.table_name_prefix = 'prefix_'
-    ActiveRecord::Base.table_name_suffix = '_suffix'
+    ActiveRecord::Base.table_name_prefix = "prefix_"
+    ActiveRecord::Base.table_name_suffix = "_suffix"
     Reminder.reset_table_name
     Reminder.reset_sequence_name
     Reminder.reset_column_information
@@ -529,7 +490,7 @@ class MigrationTest < ActiveRecord::TestCase
   def test_create_table_with_binary_column
     assert_nothing_raised {
       Person.connection.create_table :binary_testings do |t|
-        t.column "data", :binary, :null => false
+        t.column "data", :binary, null: false
       end
     }
 
@@ -543,11 +504,10 @@ class MigrationTest < ActiveRecord::TestCase
 
   unless mysql_enforcing_gtid_consistency?
     def test_create_table_with_query
-      Person.connection.create_table(:person, force: true)
-
-      Person.connection.create_table :table_from_query_testings, as: "SELECT id FROM person"
+      Person.connection.create_table :table_from_query_testings, as: "SELECT id FROM people WHERE id = 1"
 
       columns = Person.connection.columns(:table_from_query_testings)
+      assert_equal [1], Person.connection.select_values("SELECT * FROM table_from_query_testings")
       assert_equal 1, columns.length
       assert_equal "id", columns.first.name
     ensure
@@ -555,11 +515,10 @@ class MigrationTest < ActiveRecord::TestCase
     end
 
     def test_create_table_with_query_from_relation
-      Person.connection.create_table(:person, force: true)
-
-      Person.connection.create_table :table_from_query_testings, as: Person.select(:id)
+      Person.connection.create_table :table_from_query_testings, as: Person.select(:id).where(id: 1)
 
       columns = Person.connection.columns(:table_from_query_testings)
+      assert_equal [1], Person.connection.select_values("SELECT * FROM table_from_query_testings")
       assert_equal 1, columns.length
       assert_equal "id", columns.first.name
     ensure
@@ -567,6 +526,23 @@ class MigrationTest < ActiveRecord::TestCase
     end
   end
 
+  if current_adapter?(:SQLite3Adapter)
+    def test_allows_sqlite3_rollback_on_invalid_column_type
+      Person.connection.create_table :something, force: true do |t|
+        t.column :number, :integer
+        t.column :name, :string
+        t.column :foo, :bar
+      end
+      assert Person.connection.column_exists?(:something, :foo)
+      assert_nothing_raised { Person.connection.remove_column :something, :foo, :bar }
+      assert !Person.connection.column_exists?(:something, :foo)
+      assert Person.connection.column_exists?(:something, :name)
+      assert Person.connection.column_exists?(:something, :number)
+    ensure
+      Person.connection.drop_table :something, if_exists: true
+    end
+  end
+
   if current_adapter? :OracleAdapter
     def test_create_table_with_custom_sequence_name
       # table name is 29 chars, the standard sequence name will
@@ -574,7 +550,7 @@ class MigrationTest < ActiveRecord::TestCase
       assert_nothing_raised do
         begin
           Person.connection.create_table :table_with_name_thats_just_ok do |t|
-            t.column :foo, :string, :null => false
+            t.column :foo, :string, null: false
           end
         ensure
           Person.connection.drop_table :table_with_name_thats_just_ok rescue nil
@@ -585,15 +561,15 @@ class MigrationTest < ActiveRecord::TestCase
       assert_nothing_raised do
         begin
           Person.connection.create_table :table_with_name_thats_just_ok,
-            :sequence_name => 'suitably_short_seq' do |t|
-            t.column :foo, :string, :null => false
+            sequence_name: "suitably_short_seq" do |t|
+            t.column :foo, :string, null: false
           end
 
           Person.connection.execute("select suitably_short_seq.nextval from dual")
 
         ensure
           Person.connection.drop_table :table_with_name_thats_just_ok,
-            :sequence_name => 'suitably_short_seq' rescue nil
+            sequence_name: "suitably_short_seq" rescue nil
         end
       end
 
@@ -607,8 +583,8 @@ class MigrationTest < ActiveRecord::TestCase
   if current_adapter?(:Mysql2Adapter, :PostgreSQLAdapter)
     def test_out_of_range_integer_limit_should_raise
       e = assert_raise(ActiveRecord::ActiveRecordError, "integer limit didn't raise") do
-        Person.connection.create_table :test_integer_limits, :force => true do |t|
-          t.column :bigone, :integer, :limit => 10
+        Person.connection.create_table :test_integer_limits, force: true do |t|
+          t.column :bigone, :integer, limit: 10
         end
       end
 
@@ -704,7 +680,7 @@ class MigrationTest < ActiveRecord::TestCase
     end
   end
 
-  protected
+  private
     # This is needed to isolate class_attribute assignments like `table_name_prefix`
     # for each test case.
     def new_isolated_reminder_class
@@ -742,13 +718,13 @@ end
 class ReservedWordsMigrationTest < ActiveRecord::TestCase
   def test_drop_index_from_table_named_values
     connection = Person.connection
-    connection.create_table :values, :force => true do |t|
+    connection.create_table :values, force: true do |t|
       t.integer :value
     end
 
     assert_nothing_raised do
       connection.add_index :values, :value
-      connection.remove_index :values, :column => :value
+      connection.remove_index :values, column: :value
     end
   ensure
     connection.drop_table :values rescue nil
@@ -763,8 +739,8 @@ class ExplicitlyNamedIndexMigrationTest < ActiveRecord::TestCase
     end
 
     assert_nothing_raised do
-      connection.add_index :values, :value, name: 'a_different_name'
-      connection.remove_index :values, column: :value, name: 'a_different_name'
+      connection.add_index :values, :value, name: "a_different_name"
+      connection.remove_index :values, column: :value, name: "a_different_name"
     end
   ensure
     connection.drop_table :values rescue nil
@@ -775,7 +751,7 @@ if ActiveRecord::Base.connection.supports_bulk_alter?
   class BulkAlterTableMigrationsTest < ActiveRecord::TestCase
     def setup
       @connection = Person.connection
-      @connection.create_table(:delete_me, :force => true) {|t| }
+      @connection.create_table(:delete_me, force: true) { |t| }
       Person.reset_column_information
       Person.reset_sequence_name
     end
@@ -789,15 +765,15 @@ if ActiveRecord::Base.connection.supports_bulk_alter?
         with_bulk_change_table do |t|
           t.column :name, :string
           t.string :qualification, :experience
-          t.integer :age, :default => 0
+          t.integer :age, default: 0
           t.date :birthdate
           t.timestamps null: true
         end
       end
 
       assert_equal 8, columns.size
-      [:name, :qualification, :experience].each {|s| assert_equal :string, column(s).type }
-      assert_equal '0', column(:age).default
+      [:name, :qualification, :experience].each { |s| assert_equal :string, column(s).type }
+      assert_equal "0", column(:age).default
     end
 
     def test_removing_columns
@@ -805,7 +781,7 @@ if ActiveRecord::Base.connection.supports_bulk_alter?
         t.string :qualification, :experience
       end
 
-      [:qualification, :experience].each {|c| assert column(c) }
+      [:qualification, :experience].each { |c| assert column(c) }
 
       assert_queries(1) do
         with_bulk_change_table do |t|
@@ -814,7 +790,7 @@ if ActiveRecord::Base.connection.supports_bulk_alter?
         end
       end
 
-      [:qualification, :experience].each {|c| assert ! column(c) }
+      [:qualification, :experience].each { |c| assert ! column(c) }
       assert column(:qualification_experience)
     end
 
@@ -828,7 +804,7 @@ if ActiveRecord::Base.connection.supports_bulk_alter?
       # Adding an index fires a query every time to check if an index already exists or not
       assert_queries(3) do
         with_bulk_change_table do |t|
-          t.index :username, :unique => true, :name => :awesome_username_index
+          t.index :username, unique: true, name: :awesome_username_index
           t.index [:name, :age]
         end
       end
@@ -836,7 +812,7 @@ if ActiveRecord::Base.connection.supports_bulk_alter?
       assert_equal 2, indexes.size
 
       name_age_index = index(:index_delete_me_on_name_and_age)
-      assert_equal ['name', 'age'].sort, name_age_index.columns.sort
+      assert_equal ["name", "age"].sort, name_age_index.columns.sort
       assert ! name_age_index.unique
 
       assert index(:awesome_username_index).unique
@@ -853,7 +829,7 @@ if ActiveRecord::Base.connection.supports_bulk_alter?
       assert_queries(3) do
         with_bulk_change_table do |t|
           t.remove_index :name
-          t.index :name, :name => :new_name_index, :unique => true
+          t.index :name, name: :new_name_index, unique: true
         end
       end
 
@@ -875,45 +851,44 @@ if ActiveRecord::Base.connection.supports_bulk_alter?
       # One query for columns (delete_me table)
       # One query for primary key (delete_me table)
       # One query to do the bulk change
-      assert_queries(3, :ignore_none => true) do
+      assert_queries(3, ignore_none: true) do
         with_bulk_change_table do |t|
-          t.change :name, :string, :default => 'NONAME'
+          t.change :name, :string, default: "NONAME"
           t.change :birthdate, :datetime
         end
       end
 
-      assert_equal 'NONAME', column(:name).default
+      assert_equal "NONAME", column(:name).default
       assert_equal :datetime, column(:birthdate).type
     end
 
-    protected
+    private
 
-    def with_bulk_change_table
-      # Reset columns/indexes cache as we're changing the table
-      @columns = @indexes = nil
+      def with_bulk_change_table
+        # Reset columns/indexes cache as we're changing the table
+        @columns = @indexes = nil
 
-      Person.connection.change_table(:delete_me, :bulk => true) do |t|
-        yield t
+        Person.connection.change_table(:delete_me, bulk: true) do |t|
+          yield t
+        end
       end
-    end
 
-    def column(name)
-      columns.detect {|c| c.name == name.to_s }
-    end
+      def column(name)
+        columns.detect { |c| c.name == name.to_s }
+      end
 
-    def columns
-      @columns ||= Person.connection.columns('delete_me')
-    end
+      def columns
+        @columns ||= Person.connection.columns("delete_me")
+      end
 
-    def index(name)
-      indexes.detect {|i| i.name == name.to_s }
-    end
+      def index(name)
+        indexes.detect { |i| i.name == name.to_s }
+      end
 
-    def indexes
-      @indexes ||= Person.connection.indexes('delete_me')
-    end
+      def indexes
+        @indexes ||= Person.connection.indexes("delete_me")
+      end
   end # AlterTableMigrationsTest
-
 end
 
 class CopyMigrationsTest < ActiveRecord::TestCase
@@ -933,16 +908,16 @@ class CopyMigrationsTest < ActiveRecord::TestCase
     @migrations_path = MIGRATIONS_ROOT + "/valid"
     @existing_migrations = Dir[@migrations_path + "/*.rb"]
 
-    copied = ActiveRecord::Migration.copy(@migrations_path, {:bukkits => MIGRATIONS_ROOT + "/to_copy"})
+    copied = ActiveRecord::Migration.copy(@migrations_path, bukkits: MIGRATIONS_ROOT + "/to_copy")
     assert File.exist?(@migrations_path + "/4_people_have_hobbies.bukkits.rb")
     assert File.exist?(@migrations_path + "/5_people_have_descriptions.bukkits.rb")
     assert_equal [@migrations_path + "/4_people_have_hobbies.bukkits.rb", @migrations_path + "/5_people_have_descriptions.bukkits.rb"], copied.map(&:filename)
 
     expected = "# This migration comes from bukkits (originally 1)"
-    assert_equal expected, IO.readlines(@migrations_path + "/4_people_have_hobbies.bukkits.rb")[0].chomp
+    assert_equal expected, IO.readlines(@migrations_path + "/4_people_have_hobbies.bukkits.rb")[1].chomp
 
     files_count = Dir[@migrations_path + "/*.rb"].length
-    copied = ActiveRecord::Migration.copy(@migrations_path, {:bukkits => MIGRATIONS_ROOT + "/to_copy"})
+    copied = ActiveRecord::Migration.copy(@migrations_path, bukkits: MIGRATIONS_ROOT + "/to_copy")
     assert_equal files_count, Dir[@migrations_path + "/*.rb"].length
     assert copied.empty?
   ensure
@@ -975,7 +950,7 @@ class CopyMigrationsTest < ActiveRecord::TestCase
     @existing_migrations = Dir[@migrations_path + "/*.rb"]
 
     travel_to(Time.utc(2010, 7, 26, 10, 10, 10)) do
-      copied = ActiveRecord::Migration.copy(@migrations_path, {:bukkits => MIGRATIONS_ROOT + "/to_copy_with_timestamps"})
+      copied = ActiveRecord::Migration.copy(@migrations_path, bukkits: MIGRATIONS_ROOT + "/to_copy_with_timestamps")
       assert File.exist?(@migrations_path + "/20100726101010_people_have_hobbies.bukkits.rb")
       assert File.exist?(@migrations_path + "/20100726101011_people_have_descriptions.bukkits.rb")
       expected = [@migrations_path + "/20100726101010_people_have_hobbies.bukkits.rb",
@@ -983,7 +958,7 @@ class CopyMigrationsTest < ActiveRecord::TestCase
       assert_equal expected, copied.map(&:filename)
 
       files_count = Dir[@migrations_path + "/*.rb"].length
-      copied = ActiveRecord::Migration.copy(@migrations_path, {:bukkits => MIGRATIONS_ROOT + "/to_copy_with_timestamps"})
+      copied = ActiveRecord::Migration.copy(@migrations_path, bukkits: MIGRATIONS_ROOT + "/to_copy_with_timestamps")
       assert_equal files_count, Dir[@migrations_path + "/*.rb"].length
       assert copied.empty?
     end
@@ -1020,12 +995,12 @@ class CopyMigrationsTest < ActiveRecord::TestCase
     @existing_migrations = Dir[@migrations_path + "/*.rb"]
 
     travel_to(Time.utc(2010, 2, 20, 10, 10, 10)) do
-      ActiveRecord::Migration.copy(@migrations_path, {:bukkits => MIGRATIONS_ROOT + "/to_copy_with_timestamps"})
+      ActiveRecord::Migration.copy(@migrations_path, bukkits: MIGRATIONS_ROOT + "/to_copy_with_timestamps")
       assert File.exist?(@migrations_path + "/20100301010102_people_have_hobbies.bukkits.rb")
       assert File.exist?(@migrations_path + "/20100301010103_people_have_descriptions.bukkits.rb")
 
       files_count = Dir[@migrations_path + "/*.rb"].length
-      copied = ActiveRecord::Migration.copy(@migrations_path, {:bukkits => MIGRATIONS_ROOT + "/to_copy_with_timestamps"})
+      copied = ActiveRecord::Migration.copy(@migrations_path, bukkits: MIGRATIONS_ROOT + "/to_copy_with_timestamps")
       assert_equal files_count, Dir[@migrations_path + "/*.rb"].length
       assert copied.empty?
     end
@@ -1038,15 +1013,15 @@ class CopyMigrationsTest < ActiveRecord::TestCase
     @migrations_path = MIGRATIONS_ROOT + "/valid"
     @existing_migrations = Dir[@migrations_path + "/*.rb"]
 
-    copied = ActiveRecord::Migration.copy(@migrations_path, {:bukkits => MIGRATIONS_ROOT + "/magic"})
+    copied = ActiveRecord::Migration.copy(@migrations_path, bukkits: MIGRATIONS_ROOT + "/magic")
     assert File.exist?(@migrations_path + "/4_currencies_have_symbols.bukkits.rb")
     assert_equal [@migrations_path + "/4_currencies_have_symbols.bukkits.rb"], copied.map(&:filename)
 
-    expected = "# coding: ISO-8859-15\n# This migration comes from bukkits (originally 1)"
-    assert_equal expected, IO.readlines(@migrations_path + "/4_currencies_have_symbols.bukkits.rb")[0..1].join.chomp
+    expected = "# frozen_string_literal: true\n# coding: ISO-8859-15\n# This migration comes from bukkits (originally 1)"
+    assert_equal expected, IO.readlines(@migrations_path + "/4_currencies_have_symbols.bukkits.rb")[0..2].join.chomp
 
     files_count = Dir[@migrations_path + "/*.rb"].length
-    copied = ActiveRecord::Migration.copy(@migrations_path, {:bukkits => MIGRATIONS_ROOT + "/magic"})
+    copied = ActiveRecord::Migration.copy(@migrations_path, bukkits: MIGRATIONS_ROOT + "/magic")
     assert_equal files_count, Dir[@migrations_path + "/*.rb"].length
     assert copied.empty?
   ensure
@@ -1063,7 +1038,7 @@ class CopyMigrationsTest < ActiveRecord::TestCase
 
     skipped = []
     on_skip = Proc.new { |name, migration| skipped << "#{name} #{migration.name}" }
-    copied = ActiveRecord::Migration.copy(@migrations_path, sources, :on_skip => on_skip)
+    copied = ActiveRecord::Migration.copy(@migrations_path, sources, on_skip: on_skip)
     assert_equal 2, copied.length
 
     assert_equal 1, skipped.length
@@ -1081,8 +1056,8 @@ class CopyMigrationsTest < ActiveRecord::TestCase
 
     skipped = []
     on_skip = Proc.new { |name, migration| skipped << "#{name} #{migration.name}" }
-    copied = ActiveRecord::Migration.copy(@migrations_path, sources, :on_skip => on_skip)
-    ActiveRecord::Migration.copy(@migrations_path, sources, :on_skip => on_skip)
+    copied = ActiveRecord::Migration.copy(@migrations_path, sources, on_skip: on_skip)
+    ActiveRecord::Migration.copy(@migrations_path, sources, on_skip: on_skip)
 
     assert_equal 2, copied.length
     assert_equal 0, skipped.length
@@ -1095,7 +1070,7 @@ class CopyMigrationsTest < ActiveRecord::TestCase
     @existing_migrations = []
 
     travel_to(Time.utc(2010, 7, 26, 10, 10, 10)) do
-      copied = ActiveRecord::Migration.copy(@migrations_path, {:bukkits => MIGRATIONS_ROOT + "/to_copy_with_timestamps"})
+      copied = ActiveRecord::Migration.copy(@migrations_path, bukkits: MIGRATIONS_ROOT + "/to_copy_with_timestamps")
       assert File.exist?(@migrations_path + "/20100726101010_people_have_hobbies.bukkits.rb")
       assert File.exist?(@migrations_path + "/20100726101011_people_have_descriptions.bukkits.rb")
       assert_equal 2, copied.length
@@ -1110,7 +1085,7 @@ class CopyMigrationsTest < ActiveRecord::TestCase
     @existing_migrations = []
 
     travel_to(Time.utc(2010, 7, 26, 10, 10, 10)) do
-      copied = ActiveRecord::Migration.copy(@migrations_path, {:bukkits => MIGRATIONS_ROOT + "/to_copy_with_timestamps"})
+      copied = ActiveRecord::Migration.copy(@migrations_path, bukkits: MIGRATIONS_ROOT + "/to_copy_with_timestamps")
       assert File.exist?(@migrations_path + "/20100726101010_people_have_hobbies.bukkits.rb")
       assert File.exist?(@migrations_path + "/20100726101011_people_have_descriptions.bukkits.rb")
       assert_equal 2, copied.length
diff --git a/activerecord/test/cases/migrator_test.rb b/activerecord/test/cases/migrator_test.rb
index 86eca53141..1047ba1367 100644
--- a/activerecord/test/cases/migrator_test.rb
+++ b/activerecord/test/cases/migrator_test.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require "cases/helper"
 require "cases/migration/helper"
 
@@ -9,9 +11,9 @@ class MigratorTest < ActiveRecord::TestCase
   class Sensor < ActiveRecord::Migration::Current
     attr_reader :went_up, :went_down
 
-    def initialize name = self.class.name, version = nil
+    def initialize(name = self.class.name, version = nil)
       super
-      @went_up  = false
+      @went_up = false
       @went_down = false
     end
 
@@ -45,30 +47,51 @@ class MigratorTest < ActiveRecord::TestCase
   end
 
   def test_migrator_with_duplicate_names
-    assert_raises(ActiveRecord::DuplicateMigrationNameError, "Multiple migrations have the name Chunky") do
-      list = [ActiveRecord::Migration.new('Chunky'), ActiveRecord::Migration.new('Chunky')]
+    e = assert_raises(ActiveRecord::DuplicateMigrationNameError) do
+      list = [ActiveRecord::Migration.new("Chunky"), ActiveRecord::Migration.new("Chunky")]
       ActiveRecord::Migrator.new(:up, list)
     end
+    assert_match(/Multiple migrations have the name Chunky/, e.message)
   end
 
   def test_migrator_with_duplicate_versions
     assert_raises(ActiveRecord::DuplicateMigrationVersionError) do
-      list = [ActiveRecord::Migration.new('Foo', 1), ActiveRecord::Migration.new('Bar', 1)]
+      list = [ActiveRecord::Migration.new("Foo", 1), ActiveRecord::Migration.new("Bar", 1)]
       ActiveRecord::Migrator.new(:up, list)
     end
   end
 
   def test_migrator_with_missing_version_numbers
     assert_raises(ActiveRecord::UnknownMigrationVersionError) do
-      list = [ActiveRecord::Migration.new('Foo', 1), ActiveRecord::Migration.new('Bar', 2)]
+      list = [ActiveRecord::Migration.new("Foo", 1), ActiveRecord::Migration.new("Bar", 2)]
       ActiveRecord::Migrator.new(:up, list, 3).run
     end
+
+    assert_raises(ActiveRecord::UnknownMigrationVersionError) do
+      list = [ActiveRecord::Migration.new("Foo", 1), ActiveRecord::Migration.new("Bar", 2)]
+      ActiveRecord::Migrator.new(:up, list, -1).run
+    end
+
+    assert_raises(ActiveRecord::UnknownMigrationVersionError) do
+      list = [ActiveRecord::Migration.new("Foo", 1), ActiveRecord::Migration.new("Bar", 2)]
+      ActiveRecord::Migrator.new(:up, list, 0).run
+    end
+
+    assert_raises(ActiveRecord::UnknownMigrationVersionError) do
+      list = [ActiveRecord::Migration.new("Foo", 1), ActiveRecord::Migration.new("Bar", 2)]
+      ActiveRecord::Migrator.new(:up, list, 3).migrate
+    end
+
+    assert_raises(ActiveRecord::UnknownMigrationVersionError) do
+      list = [ActiveRecord::Migration.new("Foo", 1), ActiveRecord::Migration.new("Bar", 2)]
+      ActiveRecord::Migrator.new(:up, list, -1).migrate
+    end
   end
 
   def test_finds_migrations
     migrations = ActiveRecord::Migrator.migrations(MIGRATIONS_ROOT + "/valid")
 
-    [[1, 'ValidPeopleHaveLastNames'], [2, 'WeNeedReminders'], [3, 'InnocentJointable']].each_with_index do |pair, i|
+    [[1, "ValidPeopleHaveLastNames"], [2, "WeNeedReminders"], [3, "InnocentJointable"]].each_with_index do |pair, i|
       assert_equal migrations[i].version, pair.first
       assert_equal migrations[i].name, pair.last
     end
@@ -77,14 +100,14 @@ class MigratorTest < ActiveRecord::TestCase
   def test_finds_migrations_in_subdirectories
     migrations = ActiveRecord::Migrator.migrations(MIGRATIONS_ROOT + "/valid_with_subdirectories")
 
-    [[1, 'ValidPeopleHaveLastNames'], [2, 'WeNeedReminders'], [3, 'InnocentJointable']].each_with_index do |pair, i|
+    [[1, "ValidPeopleHaveLastNames"], [2, "WeNeedReminders"], [3, "InnocentJointable"]].each_with_index do |pair, i|
       assert_equal migrations[i].version, pair.first
       assert_equal migrations[i].name, pair.last
     end
   end
 
   def test_finds_migrations_from_two_directories
-    directories = [MIGRATIONS_ROOT + '/valid_with_timestamps', MIGRATIONS_ROOT + '/to_copy_with_timestamps']
+    directories = [MIGRATIONS_ROOT + "/valid_with_timestamps", MIGRATIONS_ROOT + "/to_copy_with_timestamps"]
     migrations = ActiveRecord::Migrator.migrations directories
 
     [[20090101010101, "PeopleHaveHobbies"],
@@ -92,15 +115,15 @@ class MigratorTest < ActiveRecord::TestCase
      [20100101010101, "ValidWithTimestampsPeopleHaveLastNames"],
      [20100201010101, "ValidWithTimestampsWeNeedReminders"],
      [20100301010101, "ValidWithTimestampsInnocentJointable"]].each_with_index do |pair, i|
-      assert_equal pair.first, migrations[i].version
-      assert_equal pair.last, migrations[i].name
+       assert_equal pair.first, migrations[i].version
+       assert_equal pair.last, migrations[i].name
      end
   end
 
   def test_finds_migrations_in_numbered_directory
-    migrations = ActiveRecord::Migrator.migrations [MIGRATIONS_ROOT + '/10_urban']
+    migrations = ActiveRecord::Migrator.migrations [MIGRATIONS_ROOT + "/10_urban"]
     assert_equal 9, migrations[0].version
-    assert_equal 'AddExpressions', migrations[0].name
+    assert_equal "AddExpressions", migrations[0].name
   end
 
   def test_relative_migrations
@@ -109,36 +132,97 @@ class MigratorTest < ActiveRecord::TestCase
     end
 
     migration_proxy = list.find { |item|
-      item.name == 'ValidPeopleHaveLastNames'
+      item.name == "ValidPeopleHaveLastNames"
     }
-    assert migration_proxy, 'should find pending migration'
+    assert migration_proxy, "should find pending migration"
   end
 
   def test_finds_pending_migrations
-    ActiveRecord::SchemaMigration.create!(:version => '1')
-    migration_list = [ActiveRecord::Migration.new('foo', 1), ActiveRecord::Migration.new('bar', 3)]
+    ActiveRecord::SchemaMigration.create!(version: "1")
+    migration_list = [ActiveRecord::Migration.new("foo", 1), ActiveRecord::Migration.new("bar", 3)]
     migrations = ActiveRecord::Migrator.new(:up, migration_list).pending_migrations
 
     assert_equal 1, migrations.size
     assert_equal migration_list.last, migrations.first
   end
 
+  def test_migrations_status
+    path = MIGRATIONS_ROOT + "/valid"
+
+    ActiveRecord::SchemaMigration.create(version: 2)
+    ActiveRecord::SchemaMigration.create(version: 10)
+
+    assert_equal [
+      ["down", "001", "Valid people have last names"],
+      ["up",   "002", "We need reminders"],
+      ["down", "003", "Innocent jointable"],
+      ["up",   "010", "********** NO FILE **********"],
+    ], ActiveRecord::Migrator.migrations_status(path)
+  end
+
+  def test_migrations_status_in_subdirectories
+    path = MIGRATIONS_ROOT + "/valid_with_subdirectories"
+
+    ActiveRecord::SchemaMigration.create(version: 2)
+    ActiveRecord::SchemaMigration.create(version: 10)
+
+    assert_equal [
+      ["down", "001", "Valid people have last names"],
+      ["up",   "002", "We need reminders"],
+      ["down", "003", "Innocent jointable"],
+      ["up",   "010", "********** NO FILE **********"],
+    ], ActiveRecord::Migrator.migrations_status(path)
+  end
+
+  def test_migrations_status_with_schema_define_in_subdirectories
+    path = MIGRATIONS_ROOT + "/valid_with_subdirectories"
+    prev_paths = ActiveRecord::Migrator.migrations_paths
+    ActiveRecord::Migrator.migrations_paths = path
+
+    ActiveRecord::Schema.define(version: 3) do
+    end
+
+    assert_equal [
+      ["up", "001", "Valid people have last names"],
+      ["up", "002", "We need reminders"],
+      ["up", "003", "Innocent jointable"],
+    ], ActiveRecord::Migrator.migrations_status(path)
+  ensure
+    ActiveRecord::Migrator.migrations_paths = prev_paths
+  end
+
+  def test_migrations_status_from_two_directories
+    paths = [MIGRATIONS_ROOT + "/valid_with_timestamps", MIGRATIONS_ROOT + "/to_copy_with_timestamps"]
+
+    ActiveRecord::SchemaMigration.create(version: "20100101010101")
+    ActiveRecord::SchemaMigration.create(version: "20160528010101")
+
+    assert_equal [
+      ["down", "20090101010101", "People have hobbies"],
+      ["down", "20090101010202", "People have descriptions"],
+      ["up",   "20100101010101", "Valid with timestamps people have last names"],
+      ["down", "20100201010101", "Valid with timestamps we need reminders"],
+      ["down", "20100301010101", "Valid with timestamps innocent jointable"],
+      ["up",   "20160528010101", "********** NO FILE **********"],
+    ], ActiveRecord::Migrator.migrations_status(paths)
+  end
+
   def test_migrator_interleaved_migrations
-    pass_one = [Sensor.new('One', 1)]
+    pass_one = [Sensor.new("One", 1)]
 
     ActiveRecord::Migrator.new(:up, pass_one).migrate
     assert pass_one.first.went_up
     assert_not pass_one.first.went_down
 
-    pass_two = [Sensor.new('One', 1), Sensor.new('Three', 3)]
+    pass_two = [Sensor.new("One", 1), Sensor.new("Three", 3)]
     ActiveRecord::Migrator.new(:up, pass_two).migrate
     assert_not pass_two[0].went_up
     assert pass_two[1].went_up
     assert pass_two.all? { |x| !x.went_down }
 
-    pass_three = [Sensor.new('One', 1),
-                  Sensor.new('Two', 2),
-                  Sensor.new('Three', 3)]
+    pass_three = [Sensor.new("One", 1),
+                  Sensor.new("Two", 2),
+                  Sensor.new("Three", 3)]
 
     ActiveRecord::Migrator.new(:down, pass_three).migrate
     assert pass_three[0].went_down
@@ -165,7 +249,7 @@ class MigratorTest < ActiveRecord::TestCase
   end
 
   def test_current_version
-    ActiveRecord::SchemaMigration.create!(:version => '1000')
+    ActiveRecord::SchemaMigration.create!(version: "1000")
     assert_equal 1000, ActiveRecord::Migrator.current_version
   end
 
@@ -237,6 +321,7 @@ class MigratorTest < ActiveRecord::TestCase
   def test_migrator_verbosity
     _, migrations = sensors(3)
 
+    ActiveRecord::Migration.verbose = true
     ActiveRecord::Migrator.new(:up, migrations, 1).migrate
     assert_not_equal 0, ActiveRecord::Migration.message_count
 
@@ -249,7 +334,6 @@ class MigratorTest < ActiveRecord::TestCase
   def test_migrator_verbosity_off
     _, migrations = sensors(3)
 
-    ActiveRecord::Migration.message_count = 0
     ActiveRecord::Migration.verbose = false
     ActiveRecord::Migrator.new(:up, migrations, 1).migrate
     assert_equal 0, ActiveRecord::Migration.message_count
@@ -290,6 +374,27 @@ class MigratorTest < ActiveRecord::TestCase
     assert_equal [[:up, 1], [:up, 2], [:up, 3]], calls
   end
 
+  def test_migrator_output_when_running_multiple_migrations
+    _, migrator = migrator_class(3)
+
+    result = migrator.migrate("valid")
+    assert_equal(3, result.count)
+
+    # Nothing migrated from duplicate run
+    result = migrator.migrate("valid")
+    assert_equal(0, result.count)
+
+    result = migrator.rollback("valid")
+    assert_equal(1, result.count)
+  end
+
+  def test_migrator_output_when_running_single_migration
+    _, migrator = migrator_class(1)
+    result = migrator.run(:up, "valid", 1)
+
+    assert_equal(1, result.version)
+  end
+
   def test_migrator_rollback
     _, migrator = migrator_class(3)
 
@@ -313,9 +418,9 @@ class MigratorTest < ActiveRecord::TestCase
     _, migrator = migrator_class(3)
 
     ActiveRecord::Base.connection.drop_table "schema_migrations", if_exists: true
-    ActiveSupport::Deprecation.silence { assert_not ActiveRecord::Base.connection.table_exists?('schema_migrations') }
+    assert_not ActiveRecord::Base.connection.table_exists?("schema_migrations")
     migrator.migrate("valid", 1)
-    ActiveSupport::Deprecation.silence { assert ActiveRecord::Base.connection.table_exists?('schema_migrations') }
+    assert ActiveRecord::Base.connection.table_exists?("schema_migrations")
   end
 
   def test_migrator_forward
@@ -332,7 +437,7 @@ class MigratorTest < ActiveRecord::TestCase
 
   def test_only_loads_pending_migrations
     # migrate up to 1
-    ActiveRecord::SchemaMigration.create!(:version => '1')
+    ActiveRecord::SchemaMigration.create!(version: "1")
 
     calls, migrator = migrator_class(3)
     migrator.migrate("valid", nil)
@@ -344,10 +449,10 @@ class MigratorTest < ActiveRecord::TestCase
     _, migrator = migrator_class(3)
 
     migrator.migrate("valid")
-    assert_equal([1,2,3], ActiveRecord::Migrator.get_all_versions)
+    assert_equal([1, 2, 3], ActiveRecord::Migrator.get_all_versions)
 
     migrator.rollback("valid")
-    assert_equal([1,2], ActiveRecord::Migrator.get_all_versions)
+    assert_equal([1, 2], ActiveRecord::Migrator.get_all_versions)
 
     migrator.rollback("valid")
     assert_equal([1], ActiveRecord::Migrator.get_all_versions)
@@ -357,32 +462,32 @@ class MigratorTest < ActiveRecord::TestCase
   end
 
   private
-  def m(name, version)
-    x = Sensor.new name, version
-    x.extend(Module.new {
-      define_method(:up) { yield(:up, x); super() }
-      define_method(:down) { yield(:down, x); super() }
-    }) if block_given?
-  end
-
-  def sensors(count)
-    calls = []
-    migrations = count.times.map { |i|
-      m(nil, i + 1) { |c,migration|
-        calls << [c, migration.version]
+    def m(name, version)
+      x = Sensor.new name, version
+      x.extend(Module.new {
+        define_method(:up) { yield(:up, x); super() }
+        define_method(:down) { yield(:down, x); super() }
+      }) if block_given?
+    end
+
+    def sensors(count)
+      calls = []
+      migrations = count.times.map { |i|
+        m(nil, i + 1) { |c, migration|
+          calls << [c, migration.version]
+        }
       }
-    }
-    [calls, migrations]
-  end
+      [calls, migrations]
+    end
 
-  def migrator_class(count)
-    calls, migrations = sensors(count)
+    def migrator_class(count)
+      calls, migrations = sensors(count)
 
-    migrator = Class.new(ActiveRecord::Migrator).extend(Module.new {
-      define_method(:migrations) { |paths|
-        migrations
-      }
-    })
-    [calls, migrator]
-  end
+      migrator = Class.new(ActiveRecord::Migrator).extend(Module.new {
+        define_method(:migrations) { |paths|
+          migrations
+        }
+      })
+      [calls, migrator]
+    end
 end
diff --git a/activerecord/test/cases/mixin_test.rb b/activerecord/test/cases/mixin_test.rb
index 7ebdcac711..fdb8ac6ab3 100644
--- a/activerecord/test/cases/mixin_test.rb
+++ b/activerecord/test/cases/mixin_test.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require "cases/helper"
 
 class Mixin < ActiveRecord::Base
@@ -10,10 +12,6 @@ class TouchTest < ActiveRecord::TestCase
     travel_to Time.now
   end
 
-  teardown do
-    travel_back
-  end
-
   def test_update
     stamped = Mixin.new
 
@@ -41,13 +39,12 @@ class TouchTest < ActiveRecord::TestCase
 
     old_updated_at = stamped.updated_at
 
-    travel 5.minutes do
-      stamped.lft_will_change!
-      stamped.save
+    travel 5.minutes
+    stamped.lft_will_change!
+    stamped.save
 
-      assert_equal Time.now, stamped.updated_at
-      assert_equal old_updated_at, stamped.created_at
-    end
+    assert_equal Time.now, stamped.updated_at
+    assert_equal old_updated_at, stamped.created_at
   end
 
   def test_create_turned_off
@@ -64,5 +61,4 @@ class TouchTest < ActiveRecord::TestCase
   ensure
     Mixin.record_timestamps = true
   end
-
 end
diff --git a/activerecord/test/cases/modules_test.rb b/activerecord/test/cases/modules_test.rb
index 486bcc22df..060d555607 100644
--- a/activerecord/test/cases/modules_test.rb
+++ b/activerecord/test/cases/modules_test.rb
@@ -1,8 +1,10 @@
+# frozen_string_literal: true
+
 require "cases/helper"
-require 'models/company_in_module'
-require 'models/shop'
-require 'models/developer'
-require 'models/computer'
+require "models/company_in_module"
+require "models/shop"
+require "models/developer"
+require "models/computer"
 
 class ModulesTest < ActiveRecord::TestCase
   fixtures :accounts, :companies, :projects, :developers, :collections, :products, :variants
@@ -31,7 +33,7 @@ class ModulesTest < ActiveRecord::TestCase
   def test_module_spanning_associations
     firm = MyApplication::Business::Firm.first
     assert !firm.clients.empty?, "Firm should have clients"
-    assert_nil firm.class.table_name.match('::'), "Firm shouldn't have the module appear in its table name"
+    assert_nil firm.class.table_name.match("::"), "Firm shouldn't have the module appear in its table name"
   end
 
   def test_module_spanning_has_and_belongs_to_many_associations
@@ -41,7 +43,7 @@ class ModulesTest < ActiveRecord::TestCase
   end
 
   def test_associations_spanning_cross_modules
-    account = MyApplication::Billing::Account.all.merge!(:order => 'id').first
+    account = MyApplication::Billing::Account.all.merge!(order: "id").first
     assert_kind_of MyApplication::Business::Firm, account.firm
     assert_kind_of MyApplication::Billing::Firm, account.qualified_billing_firm
     assert_kind_of MyApplication::Billing::Firm, account.unqualified_billing_firm
@@ -50,14 +52,14 @@ class ModulesTest < ActiveRecord::TestCase
   end
 
   def test_find_account_and_include_company
-    account = MyApplication::Billing::Account.all.merge!(:includes => :firm).find(1)
+    account = MyApplication::Billing::Account.all.merge!(includes: :firm).find(1)
     assert_kind_of MyApplication::Business::Firm, account.firm
   end
 
   def test_table_name
-    assert_equal 'accounts', MyApplication::Billing::Account.table_name, 'table_name for ActiveRecord model in module'
-    assert_equal 'companies', MyApplication::Business::Client.table_name, 'table_name for ActiveRecord model subclass'
-    assert_equal 'company_contacts', MyApplication::Business::Client::Contact.table_name, 'table_name for ActiveRecord model enclosed by another ActiveRecord model'
+    assert_equal "accounts", MyApplication::Billing::Account.table_name, "table_name for ActiveRecord model in module"
+    assert_equal "companies", MyApplication::Business::Client.table_name, "table_name for ActiveRecord model subclass"
+    assert_equal "company_contacts", MyApplication::Business::Client::Contact.table_name, "table_name for ActiveRecord model enclosed by another ActiveRecord model"
   end
 
   def test_assign_ids
@@ -73,8 +75,8 @@ class ModulesTest < ActiveRecord::TestCase
     clients = []
 
     assert_nothing_raised do
-      clients << MyApplication::Business::Client.references(:accounts).merge!(:includes => {:firm => :account}, :where => 'accounts.id IS NOT NULL').find(3)
-      clients << MyApplication::Business::Client.includes(:firm => :account).find(3)
+      clients << MyApplication::Business::Client.references(:accounts).merge!(includes: { firm: :account }, where: "accounts.id IS NOT NULL").find(3)
+      clients << MyApplication::Business::Client.includes(firm: :account).find(3)
     end
 
     clients.each do |client|
@@ -85,9 +87,9 @@ class ModulesTest < ActiveRecord::TestCase
   end
 
   def test_module_table_name_prefix
-    assert_equal 'prefixed_companies', MyApplication::Business::Prefixed::Company.table_name, 'inferred table_name for ActiveRecord model in module with table_name_prefix'
-    assert_equal 'prefixed_companies', MyApplication::Business::Prefixed::Nested::Company.table_name, 'table_name for ActiveRecord model in nested module with a parent table_name_prefix'
-    assert_equal 'companies', MyApplication::Business::Prefixed::Firm.table_name, 'explicit table_name for ActiveRecord model in module with table_name_prefix should not be prefixed'
+    assert_equal "prefixed_companies", MyApplication::Business::Prefixed::Company.table_name, "inferred table_name for ActiveRecord model in module with table_name_prefix"
+    assert_equal "prefixed_companies", MyApplication::Business::Prefixed::Nested::Company.table_name, "table_name for ActiveRecord model in nested module with a parent table_name_prefix"
+    assert_equal "companies", MyApplication::Business::Prefixed::Firm.table_name, "explicit table_name for ActiveRecord model in module with table_name_prefix should not be prefixed"
   end
 
   def test_module_table_name_prefix_with_global_prefix
@@ -101,21 +103,21 @@ class ModulesTest < ActiveRecord::TestCase
                 MyApplication::Business::Prefixed::Nested::Company,
                 MyApplication::Billing::Account ]
 
-    ActiveRecord::Base.table_name_prefix = 'global_'
+    ActiveRecord::Base.table_name_prefix = "global_"
     classes.each(&:reset_table_name)
-    assert_equal 'global_companies', MyApplication::Business::Company.table_name, 'inferred table_name for ActiveRecord model in module without table_name_prefix'
-    assert_equal 'prefixed_companies', MyApplication::Business::Prefixed::Company.table_name, 'inferred table_name for ActiveRecord model in module with table_name_prefix'
-    assert_equal 'prefixed_companies', MyApplication::Business::Prefixed::Nested::Company.table_name, 'table_name for ActiveRecord model in nested module with a parent table_name_prefix'
-    assert_equal 'companies', MyApplication::Business::Prefixed::Firm.table_name, 'explicit table_name for ActiveRecord model in module with table_name_prefix should not be prefixed'
+    assert_equal "global_companies", MyApplication::Business::Company.table_name, "inferred table_name for ActiveRecord model in module without table_name_prefix"
+    assert_equal "prefixed_companies", MyApplication::Business::Prefixed::Company.table_name, "inferred table_name for ActiveRecord model in module with table_name_prefix"
+    assert_equal "prefixed_companies", MyApplication::Business::Prefixed::Nested::Company.table_name, "table_name for ActiveRecord model in nested module with a parent table_name_prefix"
+    assert_equal "companies", MyApplication::Business::Prefixed::Firm.table_name, "explicit table_name for ActiveRecord model in module with table_name_prefix should not be prefixed"
   ensure
-    ActiveRecord::Base.table_name_prefix = ''
+    ActiveRecord::Base.table_name_prefix = ""
     classes.each(&:reset_table_name)
   end
 
   def test_module_table_name_suffix
-    assert_equal 'companies_suffixed', MyApplication::Business::Suffixed::Company.table_name, 'inferred table_name for ActiveRecord model in module with table_name_suffix'
-    assert_equal 'companies_suffixed', MyApplication::Business::Suffixed::Nested::Company.table_name, 'table_name for ActiveRecord model in nested module with a parent table_name_suffix'
-    assert_equal 'companies', MyApplication::Business::Suffixed::Firm.table_name, 'explicit table_name for ActiveRecord model in module with table_name_suffix should not be suffixed'
+    assert_equal "companies_suffixed", MyApplication::Business::Suffixed::Company.table_name, "inferred table_name for ActiveRecord model in module with table_name_suffix"
+    assert_equal "companies_suffixed", MyApplication::Business::Suffixed::Nested::Company.table_name, "table_name for ActiveRecord model in nested module with a parent table_name_suffix"
+    assert_equal "companies", MyApplication::Business::Suffixed::Firm.table_name, "explicit table_name for ActiveRecord model in module with table_name_suffix should not be suffixed"
   end
 
   def test_module_table_name_suffix_with_global_suffix
@@ -129,14 +131,14 @@ class ModulesTest < ActiveRecord::TestCase
                 MyApplication::Business::Suffixed::Nested::Company,
                 MyApplication::Billing::Account ]
 
-    ActiveRecord::Base.table_name_suffix = '_global'
+    ActiveRecord::Base.table_name_suffix = "_global"
     classes.each(&:reset_table_name)
-    assert_equal 'companies_global', MyApplication::Business::Company.table_name, 'inferred table_name for ActiveRecord model in module without table_name_suffix'
-    assert_equal 'companies_suffixed', MyApplication::Business::Suffixed::Company.table_name, 'inferred table_name for ActiveRecord model in module with table_name_suffix'
-    assert_equal 'companies_suffixed', MyApplication::Business::Suffixed::Nested::Company.table_name, 'table_name for ActiveRecord model in nested module with a parent table_name_suffix'
-    assert_equal 'companies', MyApplication::Business::Suffixed::Firm.table_name, 'explicit table_name for ActiveRecord model in module with table_name_suffix should not be suffixed'
+    assert_equal "companies_global", MyApplication::Business::Company.table_name, "inferred table_name for ActiveRecord model in module without table_name_suffix"
+    assert_equal "companies_suffixed", MyApplication::Business::Suffixed::Company.table_name, "inferred table_name for ActiveRecord model in module with table_name_suffix"
+    assert_equal "companies_suffixed", MyApplication::Business::Suffixed::Nested::Company.table_name, "table_name for ActiveRecord model in nested module with a parent table_name_suffix"
+    assert_equal "companies", MyApplication::Business::Suffixed::Firm.table_name, "explicit table_name for ActiveRecord model in module with table_name_suffix should not be suffixed"
   ensure
-    ActiveRecord::Base.table_name_suffix = ''
+    ActiveRecord::Base.table_name_suffix = ""
     classes.each(&:reset_table_name)
   end
 
diff --git a/activerecord/test/cases/multiparameter_attributes_test.rb b/activerecord/test/cases/multiparameter_attributes_test.rb
index d05cb22740..59be4dc5a8 100644
--- a/activerecord/test/cases/multiparameter_attributes_test.rb
+++ b/activerecord/test/cases/multiparameter_attributes_test.rb
@@ -1,6 +1,8 @@
+# frozen_string_literal: true
+
 require "cases/helper"
-require 'models/topic'
-require 'models/customer'
+require "models/topic"
+require "models/customer"
 
 class MultiParameterAttributeTest < ActiveRecord::TestCase
   fixtures :topics
@@ -202,6 +204,20 @@ class MultiParameterAttributeTest < ActiveRecord::TestCase
     Topic.reset_column_information
   end
 
+  def test_multiparameter_attributes_on_time_with_time_zone_aware_attributes_and_invalid_time_params
+    with_timezone_config aware_attributes: true do
+      Topic.reset_column_information
+      attributes = {
+        "written_on(1i)" => "2004", "written_on(2i)" => "", "written_on(3i)" => ""
+      }
+      topic = Topic.find(1)
+      topic.attributes = attributes
+      assert_nil topic.written_on
+    end
+  ensure
+    Topic.reset_column_information
+  end
+
   def test_multiparameter_attributes_on_time_with_time_zone_aware_attributes_false
     with_timezone_config default: :local, aware_attributes: false, zone: -28800 do
       attributes = {
@@ -246,10 +262,23 @@ class MultiParameterAttributeTest < ActiveRecord::TestCase
         topic.attributes = attributes
         assert_equal Time.zone.local(2000, 1, 1, 16, 24, 0), topic.bonus_time
         assert_not topic.bonus_time.utc?
+
+        attributes = {
+          "written_on(1i)" => "2000", "written_on(2i)" => "", "written_on(3i)" => "",
+          "written_on(4i)" => "", "written_on(5i)" => ""
+        }
+        topic.attributes = attributes
+        assert_nil topic.written_on
       end
     ensure
       Topic.reset_column_information
     end
+
+    def test_multiparameter_attributes_setting_time_attribute
+      topic = Topic.new("bonus_time(4i)" => "01", "bonus_time(5i)" => "05")
+      assert_equal 1, topic.bonus_time.hour
+      assert_equal 5, topic.bonus_time.min
+    end
   end
 
   def test_multiparameter_attributes_on_time_with_empty_seconds
@@ -264,16 +293,15 @@ class MultiParameterAttributeTest < ActiveRecord::TestCase
     end
   end
 
-  unless current_adapter? :OracleAdapter
-    def test_multiparameter_attributes_setting_time_attribute
-      topic = Topic.new( "bonus_time(4i)"=> "01", "bonus_time(5i)" => "05" )
-      assert_equal 1, topic.bonus_time.hour
-      assert_equal 5, topic.bonus_time.min
-    end
+  def test_multiparameter_attributes_setting_date_attribute
+    topic = Topic.new("written_on(1i)" => "1952", "written_on(2i)" => "3", "written_on(3i)" => "11")
+    assert_equal 1952, topic.written_on.year
+    assert_equal 3, topic.written_on.month
+    assert_equal 11, topic.written_on.day
   end
 
-  def test_multiparameter_attributes_setting_date_attribute
-    topic = Topic.new( "written_on(1i)" => "1952", "written_on(2i)" => "3", "written_on(3i)" => "11" )
+  def test_create_with_multiparameter_attributes_setting_date_attribute
+    topic = Topic.create_with("written_on(1i)" => "1952", "written_on(2i)" => "3", "written_on(3i)" => "11").new
     assert_equal 1952, topic.written_on.year
     assert_equal 3, topic.written_on.month
     assert_equal 11, topic.written_on.day
@@ -281,11 +309,25 @@ class MultiParameterAttributeTest < ActiveRecord::TestCase
 
   def test_multiparameter_attributes_setting_date_and_time_attribute
     topic = Topic.new(
-        "written_on(1i)" => "1952",
-        "written_on(2i)" => "3",
-        "written_on(3i)" => "11",
-        "written_on(4i)" => "13",
-        "written_on(5i)" => "55")
+      "written_on(1i)" => "1952",
+      "written_on(2i)" => "3",
+      "written_on(3i)" => "11",
+      "written_on(4i)" => "13",
+      "written_on(5i)" => "55")
+    assert_equal 1952, topic.written_on.year
+    assert_equal 3, topic.written_on.month
+    assert_equal 11, topic.written_on.day
+    assert_equal 13, topic.written_on.hour
+    assert_equal 55, topic.written_on.min
+  end
+
+  def test_create_with_multiparameter_attributes_setting_date_and_time_attribute
+    topic = Topic.create_with(
+      "written_on(1i)" => "1952",
+      "written_on(2i)" => "3",
+      "written_on(3i)" => "11",
+      "written_on(4i)" => "13",
+      "written_on(5i)" => "55").new
     assert_equal 1952, topic.written_on.year
     assert_equal 3, topic.written_on.month
     assert_equal 11, topic.written_on.day
@@ -294,8 +336,8 @@ class MultiParameterAttributeTest < ActiveRecord::TestCase
   end
 
   def test_multiparameter_attributes_setting_time_but_not_date_on_date_field
-    assert_raise( ActiveRecord::MultiparameterAssignmentErrors ) do
-      Topic.new( "written_on(4i)" => "13", "written_on(5i)" => "55" )
+    assert_raise(ActiveRecord::MultiparameterAssignmentErrors) do
+      Topic.new("written_on(4i)" => "13", "written_on(5i)" => "55")
     end
   end
 
@@ -343,4 +385,15 @@ class MultiParameterAttributeTest < ActiveRecord::TestCase
 
     assert_equal("address", ex.errors[0].attribute)
   end
+
+  def test_multiparameter_assigned_attributes_did_not_come_from_user
+    topic = Topic.new(
+      "written_on(1i)" => "1952",
+      "written_on(2i)" => "3",
+      "written_on(3i)" => "11",
+      "written_on(4i)" => "13",
+      "written_on(5i)" => "55",
+    )
+    refute_predicate topic, :written_on_came_from_user?
+  end
 end
diff --git a/activerecord/test/cases/multiple_db_test.rb b/activerecord/test/cases/multiple_db_test.rb
index a4fbf579a1..192d2f5251 100644
--- a/activerecord/test/cases/multiple_db_test.rb
+++ b/activerecord/test/cases/multiple_db_test.rb
@@ -1,7 +1,9 @@
+# frozen_string_literal: true
+
 require "cases/helper"
-require 'models/entrant'
-require 'models/bird'
-require 'models/course'
+require "models/entrant"
+require "models/bird"
+require "models/course"
 
 class MultipleDbTest < ActiveRecord::TestCase
   self.use_transactional_tests = false
@@ -60,7 +62,7 @@ class MultipleDbTest < ActiveRecord::TestCase
 
     ActiveSupport::Dependencies.clear
     Object.send(:remove_const, :Course)
-    require_dependency 'models/course'
+    require_dependency "models/course"
 
     assert Course.connection
   end
@@ -90,14 +92,9 @@ class MultipleDbTest < ActiveRecord::TestCase
     assert_equal "Ruby Developer", Entrant.find(1).name
   end
 
-  def test_arel_table_engines
-    assert_not_equal Entrant.arel_engine, Bird.arel_engine
-    assert_not_equal Entrant.arel_engine, Course.arel_engine
-  end
-
   def test_connection
-    assert_equal Entrant.arel_engine.connection.object_id, Bird.arel_engine.connection.object_id
-    assert_not_equal Entrant.arel_engine.connection.object_id, Course.arel_engine.connection.object_id
+    assert_same Entrant.connection, Bird.connection
+    assert_not_same Entrant.connection, Course.connection
   end
 
   unless in_memory_db?
diff --git a/activerecord/test/cases/nested_attributes_test.rb b/activerecord/test/cases/nested_attributes_test.rb
index 11fb164d50..a2ccb603a9 100644
--- a/activerecord/test/cases/nested_attributes_test.rb
+++ b/activerecord/test/cases/nested_attributes_test.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require "cases/helper"
 require "models/pirate"
 require "models/ship"
@@ -9,11 +11,11 @@ require "models/man"
 require "models/interest"
 require "models/owner"
 require "models/pet"
-require 'active_support/hash_with_indifferent_access'
+require "active_support/hash_with_indifferent_access"
 
 class TestNestedAttributesInGeneral < ActiveRecord::TestCase
   teardown do
-    Pirate.accepts_nested_attributes_for :ship, :allow_destroy => true, :reject_if => proc(&:empty?)
+    Pirate.accepts_nested_attributes_for :ship, allow_destroy: true, reject_if: proc(&:empty?)
   end
 
   def test_base_should_have_an_empty_nested_attributes_options
@@ -30,28 +32,28 @@ class TestNestedAttributesInGeneral < ActiveRecord::TestCase
   end
 
   def test_should_not_build_a_new_record_using_reject_all_even_if_destroy_is_given
-    pirate = Pirate.create!(:catchphrase => "Don' botharrr talkin' like one, savvy?")
-    pirate.birds_with_reject_all_blank_attributes = [{:name => '', :color => '', :_destroy => '0'}]
+    pirate = Pirate.create!(catchphrase: "Don' botharrr talkin' like one, savvy?")
+    pirate.birds_with_reject_all_blank_attributes = [{ name: "", color: "", _destroy: "0" }]
     pirate.save!
 
     assert pirate.birds_with_reject_all_blank.empty?
   end
 
   def test_should_not_build_a_new_record_if_reject_all_blank_returns_false
-    pirate = Pirate.create!(:catchphrase => "Don' botharrr talkin' like one, savvy?")
-    pirate.birds_with_reject_all_blank_attributes = [{:name => '', :color => ''}]
+    pirate = Pirate.create!(catchphrase: "Don' botharrr talkin' like one, savvy?")
+    pirate.birds_with_reject_all_blank_attributes = [{ name: "", color: "" }]
     pirate.save!
 
     assert pirate.birds_with_reject_all_blank.empty?
   end
 
   def test_should_build_a_new_record_if_reject_all_blank_does_not_return_false
-    pirate = Pirate.create!(:catchphrase => "Don' botharrr talkin' like one, savvy?")
-    pirate.birds_with_reject_all_blank_attributes = [{:name => 'Tweetie', :color => ''}]
+    pirate = Pirate.create!(catchphrase: "Don' botharrr talkin' like one, savvy?")
+    pirate.birds_with_reject_all_blank_attributes = [{ name: "Tweetie", color: "" }]
     pirate.save!
 
     assert_equal 1, pirate.birds_with_reject_all_blank.count
-    assert_equal 'Tweetie', pirate.birds_with_reject_all_blank.first.name
+    assert_equal "Tweetie", pirate.birds_with_reject_all_blank.first.name
   end
 
   def test_should_raise_an_ArgumentError_for_non_existing_associations
@@ -63,7 +65,7 @@ class TestNestedAttributesInGeneral < ActiveRecord::TestCase
 
   def test_should_raise_an_UnknownAttributeError_for_non_existing_nested_attributes
     exception = assert_raise ActiveModel::UnknownAttributeError do
-      Pirate.new(:ship_attributes => { :sail => true })
+      Pirate.new(ship_attributes: { sail: true })
     end
     assert_equal "unknown attribute 'sail' for Ship.", exception.message
   end
@@ -72,84 +74,84 @@ class TestNestedAttributesInGeneral < ActiveRecord::TestCase
     Pirate.accepts_nested_attributes_for :ship
 
     pirate = Pirate.create!(catchphrase: "Don' botharrr talkin' like one, savvy?")
-    ship = pirate.create_ship(name: 'Nights Dirty Lightning')
+    ship = pirate.create_ship(name: "Nights Dirty Lightning")
 
-    pirate.update(ship_attributes: { '_destroy' => true, :id => ship.id })
+    pirate.update(ship_attributes: { "_destroy" => true, :id => ship.id })
 
     assert_nothing_raised { pirate.ship.reload }
   end
 
   def test_a_model_should_respond_to_underscore_destroy_and_return_if_it_is_marked_for_destruction
-    ship = Ship.create!(:name => 'Nights Dirty Lightning')
+    ship = Ship.create!(name: "Nights Dirty Lightning")
     assert !ship._destroy
     ship.mark_for_destruction
     assert ship._destroy
   end
 
   def test_reject_if_method_without_arguments
-    Pirate.accepts_nested_attributes_for :ship, :reject_if => :new_record?
+    Pirate.accepts_nested_attributes_for :ship, reject_if: :new_record?
 
-    pirate = Pirate.new(:catchphrase => "Stop wastin' me time")
-    pirate.ship_attributes = { :name => 'Black Pearl' }
-    assert_no_difference('Ship.count') { pirate.save! }
+    pirate = Pirate.new(catchphrase: "Stop wastin' me time")
+    pirate.ship_attributes = { name: "Black Pearl" }
+    assert_no_difference("Ship.count") { pirate.save! }
   end
 
   def test_reject_if_method_with_arguments
-    Pirate.accepts_nested_attributes_for :ship, :reject_if => :reject_empty_ships_on_create
+    Pirate.accepts_nested_attributes_for :ship, reject_if: :reject_empty_ships_on_create
 
-    pirate = Pirate.new(:catchphrase => "Stop wastin' me time")
-    pirate.ship_attributes = { :name => 'Red Pearl', :_reject_me_if_new => true }
-    assert_no_difference('Ship.count') { pirate.save! }
+    pirate = Pirate.new(catchphrase: "Stop wastin' me time")
+    pirate.ship_attributes = { name: "Red Pearl", _reject_me_if_new: true }
+    assert_no_difference("Ship.count") { pirate.save! }
 
     # pirate.reject_empty_ships_on_create returns false for saved pirate records
     # in the previous step note that pirate gets saved but ship fails
-    pirate.ship_attributes = { :name => 'Red Pearl', :_reject_me_if_new => true }
-    assert_difference('Ship.count') { pirate.save! }
+    pirate.ship_attributes = { name: "Red Pearl", _reject_me_if_new: true }
+    assert_difference("Ship.count") { pirate.save! }
   end
 
   def test_reject_if_with_indifferent_keys
-    Pirate.accepts_nested_attributes_for :ship, :reject_if => proc {|attributes| attributes[:name].blank? }
+    Pirate.accepts_nested_attributes_for :ship, reject_if: proc { |attributes| attributes[:name].blank? }
 
-    pirate = Pirate.new(:catchphrase => "Stop wastin' me time")
-    pirate.ship_attributes = { :name => 'Hello Pearl' }
-    assert_difference('Ship.count') { pirate.save! }
+    pirate = Pirate.new(catchphrase: "Stop wastin' me time")
+    pirate.ship_attributes = { name: "Hello Pearl" }
+    assert_difference("Ship.count") { pirate.save! }
   end
 
   def test_reject_if_with_a_proc_which_returns_true_always_for_has_one
-    Pirate.accepts_nested_attributes_for :ship, :reject_if => proc {|attributes| true }
-    pirate = Pirate.new(catchphrase: "Stop wastin' me time")
-    ship = pirate.create_ship(name: 's1')
-    pirate.update({ship_attributes: { name: 's2', id: ship.id } })
-    assert_equal 's1', ship.reload.name
+    Pirate.accepts_nested_attributes_for :ship, reject_if: proc { |attributes| true }
+    pirate = Pirate.create(catchphrase: "Stop wastin' me time")
+    ship = pirate.create_ship(name: "s1")
+    pirate.update(ship_attributes: { name: "s2", id: ship.id })
+    assert_equal "s1", ship.reload.name
   end
 
   def test_reuse_already_built_new_record
     pirate = Pirate.new
     ship_built_first = pirate.build_ship
-    pirate.ship_attributes = { name: 'Ship 1' }
+    pirate.ship_attributes = { name: "Ship 1" }
     assert_equal ship_built_first.object_id, pirate.ship.object_id
   end
 
   def test_do_not_allow_assigning_foreign_key_when_reusing_existing_new_record
     pirate = Pirate.create!(catchphrase: "Don' botharrr talkin' like one, savvy?")
     pirate.build_ship
-    pirate.ship_attributes = { name: 'Ship 1', pirate_id: pirate.id + 1 }
+    pirate.ship_attributes = { name: "Ship 1", pirate_id: pirate.id + 1 }
     assert_equal pirate.id, pirate.ship.pirate_id
   end
 
   def test_reject_if_with_a_proc_which_returns_true_always_for_has_many
-    Man.accepts_nested_attributes_for :interests, :reject_if => proc {|attributes| true }
+    Man.accepts_nested_attributes_for :interests, reject_if: proc { |attributes| true }
     man = Man.create(name: "John")
-    interest = man.interests.create(topic: 'photography')
-    man.update({interests_attributes: { topic: 'gardening', id: interest.id } })
-    assert_equal 'photography', interest.reload.topic
+    interest = man.interests.create(topic: "photography")
+    man.update(interests_attributes: { topic: "gardening", id: interest.id })
+    assert_equal "photography", interest.reload.topic
   end
 
   def test_destroy_works_independent_of_reject_if
-    Man.accepts_nested_attributes_for :interests, :reject_if => proc {|attributes| true }, :allow_destroy => true
+    Man.accepts_nested_attributes_for :interests, reject_if: proc { |attributes| true }, allow_destroy: true
     man = Man.create(name: "Jon")
-    interest = man.interests.create(topic: 'the ladies')
-    man.update({interests_attributes: { _destroy: "1", id: interest.id } })
+    interest = man.interests.create(topic: "the ladies")
+    man.update(interests_attributes: { _destroy: "1", id: interest.id })
     assert man.reload.interests.empty?
   end
 
@@ -168,27 +170,27 @@ class TestNestedAttributesInGeneral < ActiveRecord::TestCase
 
   def test_has_many_association_updating_a_single_record
     Man.accepts_nested_attributes_for(:interests)
-    man = Man.create(name: 'John')
-    interest = man.interests.create(topic: 'photography')
-    man.update({interests_attributes: {topic: 'gardening', id: interest.id}})
-    assert_equal 'gardening', interest.reload.topic
+    man = Man.create(name: "John")
+    interest = man.interests.create(topic: "photography")
+    man.update(interests_attributes: { topic: "gardening", id: interest.id })
+    assert_equal "gardening", interest.reload.topic
   end
 
   def test_reject_if_with_blank_nested_attributes_id
     # When using a select list to choose an existing 'ship' id, with include_blank: true
-    Pirate.accepts_nested_attributes_for :ship, :reject_if => proc {|attributes| attributes[:id].blank? }
+    Pirate.accepts_nested_attributes_for :ship, reject_if: proc { |attributes| attributes[:id].blank? }
 
-    pirate = Pirate.new(:catchphrase => "Stop wastin' me time")
-    pirate.ship_attributes = { :id => "" }
+    pirate = Pirate.new(catchphrase: "Stop wastin' me time")
+    pirate.ship_attributes = { id: "" }
     assert_nothing_raised { pirate.save! }
   end
 
   def test_first_and_array_index_zero_methods_return_the_same_value_when_nested_attributes_are_set_to_update_existing_record
     Man.accepts_nested_attributes_for(:interests)
-    man = Man.create(:name => "John")
-    interest = man.interests.create :topic => 'gardening'
+    man = Man.create(name: "John")
+    interest = man.interests.create topic: "gardening"
     man = Man.find man.id
-    man.interests_attributes = [{:id => interest.id, :topic => 'gardening'}]
+    man.interests_attributes = [{ id: interest.id, topic: "gardening" }]
     assert_equal man.interests.first.topic, man.interests[0].topic
   end
 
@@ -196,11 +198,11 @@ class TestNestedAttributesInGeneral < ActiveRecord::TestCase
     mean_pirate_class = Class.new(Pirate) do
       accepts_nested_attributes_for :parrot
       def parrot_attributes=(attrs)
-        super(attrs.merge(:color => "blue"))
+        super(attrs.merge(color: "blue"))
       end
     end
     mean_pirate = mean_pirate_class.new
-    mean_pirate.parrot_attributes = { :name => "James" }
+    mean_pirate.parrot_attributes = { name: "James" }
     assert_equal "James", mean_pirate.parrot.name
     assert_equal "blue", mean_pirate.parrot.color
   end
@@ -212,20 +214,20 @@ class TestNestedAttributesInGeneral < ActiveRecord::TestCase
       accepts_nested_attributes_for :parrot
     end
     mean_pirate = mean_pirate_class.new
-    mean_pirate.parrot_attributes = { :name => "James" }
+    mean_pirate.parrot_attributes = { name: "James" }
     assert_equal "James", mean_pirate.parrot.name
   end
 end
 
 class TestNestedAttributesOnAHasOneAssociation < ActiveRecord::TestCase
   def setup
-    @pirate = Pirate.create!(:catchphrase => "Don' botharrr talkin' like one, savvy?")
-    @ship = @pirate.create_ship(:name => 'Nights Dirty Lightning')
+    @pirate = Pirate.create!(catchphrase: "Don' botharrr talkin' like one, savvy?")
+    @ship = @pirate.create_ship(name: "Nights Dirty Lightning")
   end
 
   def test_should_raise_argument_error_if_trying_to_build_polymorphic_belongs_to
     exception = assert_raise ArgumentError do
-      Treasure.new(:name => 'pearl', :looter_attributes => {:catchphrase => "Arrr"})
+      Treasure.new(name: "pearl", looter_attributes: { catchphrase: "Arrr" })
     end
     assert_equal "Cannot build association `looter'. Are you trying to build a polymorphic one-to-one association?", exception.message
   end
@@ -236,15 +238,15 @@ class TestNestedAttributesOnAHasOneAssociation < ActiveRecord::TestCase
 
   def test_should_build_a_new_record_if_there_is_no_id
     @ship.destroy
-    @pirate.reload.ship_attributes = { :name => 'Davy Jones Gold Dagger' }
+    @pirate.reload.ship_attributes = { name: "Davy Jones Gold Dagger" }
 
     assert !@pirate.ship.persisted?
-    assert_equal 'Davy Jones Gold Dagger', @pirate.ship.name
+    assert_equal "Davy Jones Gold Dagger", @pirate.ship.name
   end
 
   def test_should_not_build_a_new_record_if_there_is_no_id_and_destroy_is_truthy
     @ship.destroy
-    @pirate.reload.ship_attributes = { :name => 'Davy Jones Gold Dagger', :_destroy => '1' }
+    @pirate.reload.ship_attributes = { name: "Davy Jones Gold Dagger", _destroy: "1" }
 
     assert_nil @pirate.ship
   end
@@ -257,54 +259,54 @@ class TestNestedAttributesOnAHasOneAssociation < ActiveRecord::TestCase
   end
 
   def test_should_replace_an_existing_record_if_there_is_no_id
-    @pirate.reload.ship_attributes = { :name => 'Davy Jones Gold Dagger' }
+    @pirate.reload.ship_attributes = { name: "Davy Jones Gold Dagger" }
 
     assert !@pirate.ship.persisted?
-    assert_equal 'Davy Jones Gold Dagger', @pirate.ship.name
-    assert_equal 'Nights Dirty Lightning', @ship.name
+    assert_equal "Davy Jones Gold Dagger", @pirate.ship.name
+    assert_equal "Nights Dirty Lightning", @ship.name
   end
 
   def test_should_not_replace_an_existing_record_if_there_is_no_id_and_destroy_is_truthy
-    @pirate.reload.ship_attributes = { :name => 'Davy Jones Gold Dagger', :_destroy => '1' }
+    @pirate.reload.ship_attributes = { name: "Davy Jones Gold Dagger", _destroy: "1" }
 
     assert_equal @ship, @pirate.ship
-    assert_equal 'Nights Dirty Lightning', @pirate.ship.name
+    assert_equal "Nights Dirty Lightning", @pirate.ship.name
   end
 
   def test_should_modify_an_existing_record_if_there_is_a_matching_id
-    @pirate.reload.ship_attributes = { :id => @ship.id, :name => 'Davy Jones Gold Dagger' }
+    @pirate.reload.ship_attributes = { id: @ship.id, name: "Davy Jones Gold Dagger" }
 
     assert_equal @ship, @pirate.ship
-    assert_equal 'Davy Jones Gold Dagger', @pirate.ship.name
+    assert_equal "Davy Jones Gold Dagger", @pirate.ship.name
   end
 
   def test_should_raise_RecordNotFound_if_an_id_is_given_but_doesnt_return_a_record
     exception = assert_raise ActiveRecord::RecordNotFound do
-      @pirate.ship_attributes = { :id => 1234567890 }
+      @pirate.ship_attributes = { id: 1234567890 }
     end
     assert_equal "Couldn't find Ship with ID=1234567890 for Pirate with ID=#{@pirate.id}", exception.message
   end
 
   def test_should_take_a_hash_with_string_keys_and_update_the_associated_model
-    @pirate.reload.ship_attributes = { 'id' => @ship.id, 'name' => 'Davy Jones Gold Dagger' }
+    @pirate.reload.ship_attributes = { "id" => @ship.id, "name" => "Davy Jones Gold Dagger" }
 
     assert_equal @ship, @pirate.ship
-    assert_equal 'Davy Jones Gold Dagger', @pirate.ship.name
+    assert_equal "Davy Jones Gold Dagger", @pirate.ship.name
   end
 
   def test_should_modify_an_existing_record_if_there_is_a_matching_composite_id
-    @ship.stub(:id, 'ABC1X') do
-      @pirate.ship_attributes = { :id => @ship.id, :name => 'Davy Jones Gold Dagger' }
+    @ship.stub(:id, "ABC1X") do
+      @pirate.ship_attributes = { id: @ship.id, name: "Davy Jones Gold Dagger" }
 
-      assert_equal 'Davy Jones Gold Dagger', @pirate.ship.name
+      assert_equal "Davy Jones Gold Dagger", @pirate.ship.name
     end
   end
 
   def test_should_destroy_an_existing_record_if_there_is_a_matching_id_and_destroy_is_truthy
     @pirate.ship.destroy
 
-    [1, '1', true, 'true'].each do |truth|
-      ship = @pirate.reload.create_ship(name: 'Mister Pablo')
+    [1, "1", true, "true"].each do |truth|
+      ship = @pirate.reload.create_ship(name: "Mister Pablo")
       @pirate.update(ship_attributes: { id: ship.id, _destroy: truth })
 
       assert_nil @pirate.reload.ship
@@ -313,7 +315,7 @@ class TestNestedAttributesOnAHasOneAssociation < ActiveRecord::TestCase
   end
 
   def test_should_not_destroy_an_existing_record_if_destroy_is_not_truthy
-    [nil, '0', 0, 'false', false].each do |not_truth|
+    [nil, "0", 0, "false", false].each do |not_truth|
       @pirate.update(ship_attributes: { id: @pirate.ship.id, _destroy: not_truth })
 
       assert_equal @ship, @pirate.reload.ship
@@ -321,32 +323,32 @@ class TestNestedAttributesOnAHasOneAssociation < ActiveRecord::TestCase
   end
 
   def test_should_not_destroy_an_existing_record_if_allow_destroy_is_false
-    Pirate.accepts_nested_attributes_for :ship, :allow_destroy => false, :reject_if => proc(&:empty?)
+    Pirate.accepts_nested_attributes_for :ship, allow_destroy: false, reject_if: proc(&:empty?)
 
-    @pirate.update(ship_attributes: { id: @pirate.ship.id, _destroy: '1' })
+    @pirate.update(ship_attributes: { id: @pirate.ship.id, _destroy: "1" })
 
     assert_equal @ship, @pirate.reload.ship
 
-    Pirate.accepts_nested_attributes_for :ship, :allow_destroy => true, :reject_if => proc(&:empty?)
+    Pirate.accepts_nested_attributes_for :ship, allow_destroy: true, reject_if: proc(&:empty?)
   end
 
   def test_should_also_work_with_a_HashWithIndifferentAccess
-    @pirate.ship_attributes = ActiveSupport::HashWithIndifferentAccess.new(:id => @ship.id, :name => 'Davy Jones Gold Dagger')
+    @pirate.ship_attributes = ActiveSupport::HashWithIndifferentAccess.new(id: @ship.id, name: "Davy Jones Gold Dagger")
 
     assert @pirate.ship.persisted?
-    assert_equal 'Davy Jones Gold Dagger', @pirate.ship.name
+    assert_equal "Davy Jones Gold Dagger", @pirate.ship.name
   end
 
   def test_should_work_with_update_as_well
-    @pirate.update({ catchphrase: 'Arr', ship_attributes: { id: @ship.id, name: 'Mister Pablo' } })
+    @pirate.update(catchphrase: "Arr", ship_attributes: { id: @ship.id, name: "Mister Pablo" })
     @pirate.reload
 
-    assert_equal 'Arr', @pirate.catchphrase
-    assert_equal 'Mister Pablo', @pirate.ship.name
+    assert_equal "Arr", @pirate.catchphrase
+    assert_equal "Mister Pablo", @pirate.ship.name
   end
 
   def test_should_not_destroy_the_associated_model_until_the_parent_is_saved
-    @pirate.attributes = { :ship_attributes => { :id => @ship.id, :_destroy => '1' } }
+    @pirate.attributes = { ship_attributes: { id: @ship.id, _destroy: "1" } }
 
     assert !@pirate.ship.destroyed?
     assert @pirate.ship.marked_for_destruction?
@@ -362,56 +364,55 @@ class TestNestedAttributesOnAHasOneAssociation < ActiveRecord::TestCase
   end
 
   def test_should_accept_update_only_option
-    @pirate.update(update_only_ship_attributes: { id: @pirate.ship.id, name: 'Mayflower' })
+    @pirate.update(update_only_ship_attributes: { id: @pirate.ship.id, name: "Mayflower" })
   end
 
   def test_should_create_new_model_when_nothing_is_there_and_update_only_is_true
     @ship.delete
 
-    @pirate.reload.update(update_only_ship_attributes: { name: 'Mayflower' })
+    @pirate.reload.update(update_only_ship_attributes: { name: "Mayflower" })
 
     assert_not_nil @pirate.ship
   end
 
   def test_should_update_existing_when_update_only_is_true_and_no_id_is_given
     @ship.delete
-    @ship = @pirate.create_update_only_ship(name: 'Nights Dirty Lightning')
+    @ship = @pirate.create_update_only_ship(name: "Nights Dirty Lightning")
 
-    @pirate.update(update_only_ship_attributes: { name: 'Mayflower' })
+    @pirate.update(update_only_ship_attributes: { name: "Mayflower" })
 
-    assert_equal 'Mayflower', @ship.reload.name
+    assert_equal "Mayflower", @ship.reload.name
     assert_equal @ship, @pirate.reload.ship
   end
 
   def test_should_update_existing_when_update_only_is_true_and_id_is_given
     @ship.delete
-    @ship = @pirate.create_update_only_ship(name: 'Nights Dirty Lightning')
+    @ship = @pirate.create_update_only_ship(name: "Nights Dirty Lightning")
 
-    @pirate.update(update_only_ship_attributes: { name: 'Mayflower', id: @ship.id })
+    @pirate.update(update_only_ship_attributes: { name: "Mayflower", id: @ship.id })
 
-    assert_equal 'Mayflower', @ship.reload.name
+    assert_equal "Mayflower", @ship.reload.name
     assert_equal @ship, @pirate.reload.ship
   end
 
   def test_should_destroy_existing_when_update_only_is_true_and_id_is_given_and_is_marked_for_destruction
-    Pirate.accepts_nested_attributes_for :update_only_ship, :update_only => true, :allow_destroy => true
+    Pirate.accepts_nested_attributes_for :update_only_ship, update_only: true, allow_destroy: true
     @ship.delete
-    @ship = @pirate.create_update_only_ship(name: 'Nights Dirty Lightning')
+    @ship = @pirate.create_update_only_ship(name: "Nights Dirty Lightning")
 
-    @pirate.update(update_only_ship_attributes: { name: 'Mayflower', id: @ship.id, _destroy: true })
+    @pirate.update(update_only_ship_attributes: { name: "Mayflower", id: @ship.id, _destroy: true })
 
     assert_nil @pirate.reload.ship
     assert_raise(ActiveRecord::RecordNotFound) { Ship.find(@ship.id) }
 
-    Pirate.accepts_nested_attributes_for :update_only_ship, :update_only => true, :allow_destroy => false
+    Pirate.accepts_nested_attributes_for :update_only_ship, update_only: true, allow_destroy: false
   end
-
 end
 
 class TestNestedAttributesOnABelongsToAssociation < ActiveRecord::TestCase
   def setup
-    @ship = Ship.new(:name => 'Nights Dirty Lightning')
-    @pirate = @ship.build_pirate(:catchphrase => 'Aye')
+    @ship = Ship.new(name: "Nights Dirty Lightning")
+    @pirate = @ship.build_pirate(catchphrase: "Aye")
     @ship.save!
   end
 
@@ -421,15 +422,15 @@ class TestNestedAttributesOnABelongsToAssociation < ActiveRecord::TestCase
 
   def test_should_build_a_new_record_if_there_is_no_id
     @pirate.destroy
-    @ship.reload.pirate_attributes = { :catchphrase => 'Arr' }
+    @ship.reload.pirate_attributes = { catchphrase: "Arr" }
 
     assert !@ship.pirate.persisted?
-    assert_equal 'Arr', @ship.pirate.catchphrase
+    assert_equal "Arr", @ship.pirate.catchphrase
   end
 
   def test_should_not_build_a_new_record_if_there_is_no_id_and_destroy_is_truthy
     @pirate.destroy
-    @ship.reload.pirate_attributes = { :catchphrase => 'Arr', :_destroy => '1' }
+    @ship.reload.pirate_attributes = { catchphrase: "Arr", _destroy: "1" }
 
     assert_nil @ship.pirate
   end
@@ -442,53 +443,53 @@ class TestNestedAttributesOnABelongsToAssociation < ActiveRecord::TestCase
   end
 
   def test_should_replace_an_existing_record_if_there_is_no_id
-    @ship.reload.pirate_attributes = { :catchphrase => 'Arr' }
+    @ship.reload.pirate_attributes = { catchphrase: "Arr" }
 
     assert !@ship.pirate.persisted?
-    assert_equal 'Arr', @ship.pirate.catchphrase
-    assert_equal 'Aye', @pirate.catchphrase
+    assert_equal "Arr", @ship.pirate.catchphrase
+    assert_equal "Aye", @pirate.catchphrase
   end
 
   def test_should_not_replace_an_existing_record_if_there_is_no_id_and_destroy_is_truthy
-    @ship.reload.pirate_attributes = { :catchphrase => 'Arr', :_destroy => '1' }
+    @ship.reload.pirate_attributes = { catchphrase: "Arr", _destroy: "1" }
 
     assert_equal @pirate, @ship.pirate
-    assert_equal 'Aye', @ship.pirate.catchphrase
+    assert_equal "Aye", @ship.pirate.catchphrase
   end
 
   def test_should_modify_an_existing_record_if_there_is_a_matching_id
-    @ship.reload.pirate_attributes = { :id => @pirate.id, :catchphrase => 'Arr' }
+    @ship.reload.pirate_attributes = { id: @pirate.id, catchphrase: "Arr" }
 
     assert_equal @pirate, @ship.pirate
-    assert_equal 'Arr', @ship.pirate.catchphrase
+    assert_equal "Arr", @ship.pirate.catchphrase
   end
 
   def test_should_raise_RecordNotFound_if_an_id_is_given_but_doesnt_return_a_record
     exception = assert_raise ActiveRecord::RecordNotFound do
-      @ship.pirate_attributes = { :id => 1234567890 }
+      @ship.pirate_attributes = { id: 1234567890 }
     end
     assert_equal "Couldn't find Pirate with ID=1234567890 for Ship with ID=#{@ship.id}", exception.message
   end
 
   def test_should_take_a_hash_with_string_keys_and_update_the_associated_model
-    @ship.reload.pirate_attributes = { 'id' => @pirate.id, 'catchphrase' => 'Arr' }
+    @ship.reload.pirate_attributes = { "id" => @pirate.id, "catchphrase" => "Arr" }
 
     assert_equal @pirate, @ship.pirate
-    assert_equal 'Arr', @ship.pirate.catchphrase
+    assert_equal "Arr", @ship.pirate.catchphrase
   end
 
   def test_should_modify_an_existing_record_if_there_is_a_matching_composite_id
-    @pirate.stub(:id, 'ABC1X') do
-      @ship.pirate_attributes = { :id => @pirate.id, :catchphrase => 'Arr' }
+    @pirate.stub(:id, "ABC1X") do
+      @ship.pirate_attributes = { id: @pirate.id, catchphrase: "Arr" }
 
-      assert_equal 'Arr', @ship.pirate.catchphrase
+      assert_equal "Arr", @ship.pirate.catchphrase
     end
   end
 
   def test_should_destroy_an_existing_record_if_there_is_a_matching_id_and_destroy_is_truthy
     @ship.pirate.destroy
-    [1, '1', true, 'true'].each do |truth|
-      pirate = @ship.reload.create_pirate(catchphrase: 'Arr')
+    [1, "1", true, "true"].each do |truth|
+      pirate = @ship.reload.create_pirate(catchphrase: "Arr")
       @ship.update(pirate_attributes: { id: pirate.id, _destroy: truth })
       assert_raise(ActiveRecord::RecordNotFound) { pirate.reload }
     end
@@ -509,33 +510,33 @@ class TestNestedAttributesOnABelongsToAssociation < ActiveRecord::TestCase
   end
 
   def test_should_not_destroy_an_existing_record_if_destroy_is_not_truthy
-    [nil, '0', 0, 'false', false].each do |not_truth|
+    [nil, "0", 0, "false", false].each do |not_truth|
       @ship.update(pirate_attributes: { id: @ship.pirate.id, _destroy: not_truth })
       assert_nothing_raised { @ship.pirate.reload }
     end
   end
 
   def test_should_not_destroy_an_existing_record_if_allow_destroy_is_false
-    Ship.accepts_nested_attributes_for :pirate, :allow_destroy => false, :reject_if => proc(&:empty?)
+    Ship.accepts_nested_attributes_for :pirate, allow_destroy: false, reject_if: proc(&:empty?)
 
-    @ship.update(pirate_attributes: { id: @ship.pirate.id, _destroy: '1' })
+    @ship.update(pirate_attributes: { id: @ship.pirate.id, _destroy: "1" })
     assert_nothing_raised { @ship.pirate.reload }
   ensure
-    Ship.accepts_nested_attributes_for :pirate, :allow_destroy => true, :reject_if => proc(&:empty?)
+    Ship.accepts_nested_attributes_for :pirate, allow_destroy: true, reject_if: proc(&:empty?)
   end
 
   def test_should_work_with_update_as_well
-    @ship.update({ name: 'Mister Pablo', pirate_attributes: { catchphrase: 'Arr' } })
+    @ship.update(name: "Mister Pablo", pirate_attributes: { catchphrase: "Arr" })
     @ship.reload
 
-    assert_equal 'Mister Pablo', @ship.name
-    assert_equal 'Arr', @ship.pirate.catchphrase
+    assert_equal "Mister Pablo", @ship.name
+    assert_equal "Arr", @ship.pirate.catchphrase
   end
 
   def test_should_not_destroy_the_associated_model_until_the_parent_is_saved
     pirate = @ship.pirate
 
-    @ship.attributes = { :pirate_attributes => { :id => pirate.id, '_destroy' => true } }
+    @ship.attributes = { pirate_attributes: { :id => pirate.id, "_destroy" => true } }
     assert_nothing_raised { Pirate.find(pirate.id) }
     @ship.save
     assert_raise(ActiveRecord::RecordNotFound) { Pirate.find(pirate.id) }
@@ -547,40 +548,40 @@ class TestNestedAttributesOnABelongsToAssociation < ActiveRecord::TestCase
 
   def test_should_create_new_model_when_nothing_is_there_and_update_only_is_true
     @pirate.delete
-    @ship.reload.attributes = { :update_only_pirate_attributes => { :catchphrase => 'Arr' } }
+    @ship.reload.attributes = { update_only_pirate_attributes: { catchphrase: "Arr" } }
 
     assert !@ship.update_only_pirate.persisted?
   end
 
   def test_should_update_existing_when_update_only_is_true_and_no_id_is_given
     @pirate.delete
-    @pirate = @ship.create_update_only_pirate(catchphrase: 'Aye')
+    @pirate = @ship.create_update_only_pirate(catchphrase: "Aye")
 
-    @ship.update(update_only_pirate_attributes: { catchphrase: 'Arr' })
-    assert_equal 'Arr', @pirate.reload.catchphrase
+    @ship.update(update_only_pirate_attributes: { catchphrase: "Arr" })
+    assert_equal "Arr", @pirate.reload.catchphrase
     assert_equal @pirate, @ship.reload.update_only_pirate
   end
 
   def test_should_update_existing_when_update_only_is_true_and_id_is_given
     @pirate.delete
-    @pirate = @ship.create_update_only_pirate(catchphrase: 'Aye')
+    @pirate = @ship.create_update_only_pirate(catchphrase: "Aye")
 
-    @ship.update(update_only_pirate_attributes: { catchphrase: 'Arr', id: @pirate.id })
+    @ship.update(update_only_pirate_attributes: { catchphrase: "Arr", id: @pirate.id })
 
-    assert_equal 'Arr', @pirate.reload.catchphrase
+    assert_equal "Arr", @pirate.reload.catchphrase
     assert_equal @pirate, @ship.reload.update_only_pirate
   end
 
   def test_should_destroy_existing_when_update_only_is_true_and_id_is_given_and_is_marked_for_destruction
-    Ship.accepts_nested_attributes_for :update_only_pirate, :update_only => true, :allow_destroy => true
+    Ship.accepts_nested_attributes_for :update_only_pirate, update_only: true, allow_destroy: true
     @pirate.delete
-    @pirate = @ship.create_update_only_pirate(catchphrase: 'Aye')
+    @pirate = @ship.create_update_only_pirate(catchphrase: "Aye")
 
-    @ship.update(update_only_pirate_attributes: { catchphrase: 'Arr', id: @pirate.id, _destroy: true })
+    @ship.update(update_only_pirate_attributes: { catchphrase: "Arr", id: @pirate.id, _destroy: true })
 
     assert_raise(ActiveRecord::RecordNotFound) { @pirate.reload }
 
-    Ship.accepts_nested_attributes_for :update_only_pirate, :update_only => true, :allow_destroy => false
+    Ship.accepts_nested_attributes_for :update_only_pirate, update_only: true, allow_destroy: false
   end
 end
 
@@ -597,10 +598,9 @@ module NestedAttributesOnACollectionAssociationTests
   end
 
   def test_should_save_only_one_association_on_create
-    pirate = Pirate.create!({
-      :catchphrase => 'Arr',
-      association_getter => { 'foo' => { :name => 'Grace OMalley' } }
-    })
+    pirate = Pirate.create!(
+      :catchphrase => "Arr",
+      association_getter => { "foo" => { name: "Grace OMalley" } })
 
     assert_equal 1, pirate.reload.send(@association_name).count
   end
@@ -608,90 +608,90 @@ module NestedAttributesOnACollectionAssociationTests
   def test_should_take_a_hash_with_string_keys_and_assign_the_attributes_to_the_associated_models
     @alternate_params[association_getter].stringify_keys!
     @pirate.update @alternate_params
-    assert_equal ['Grace OMalley', 'Privateers Greed'], [@child_1.reload.name, @child_2.reload.name]
+    assert_equal ["Grace OMalley", "Privateers Greed"], [@child_1.reload.name, @child_2.reload.name]
   end
 
   def test_should_take_an_array_and_assign_the_attributes_to_the_associated_models
     @pirate.send(association_setter, @alternate_params[association_getter].values)
     @pirate.save
-    assert_equal ['Grace OMalley', 'Privateers Greed'], [@child_1.reload.name, @child_2.reload.name]
+    assert_equal ["Grace OMalley", "Privateers Greed"], [@child_1.reload.name, @child_2.reload.name]
   end
 
   def test_should_also_work_with_a_HashWithIndifferentAccess
-    @pirate.send(association_setter, ActiveSupport::HashWithIndifferentAccess.new('foo' => ActiveSupport::HashWithIndifferentAccess.new(:id => @child_1.id, :name => 'Grace OMalley')))
+    @pirate.send(association_setter, ActiveSupport::HashWithIndifferentAccess.new("foo" => ActiveSupport::HashWithIndifferentAccess.new(id: @child_1.id, name: "Grace OMalley")))
     @pirate.save
-    assert_equal 'Grace OMalley', @child_1.reload.name
+    assert_equal "Grace OMalley", @child_1.reload.name
   end
 
   def test_should_take_a_hash_and_assign_the_attributes_to_the_associated_models
     @pirate.attributes = @alternate_params
-    assert_equal 'Grace OMalley', @pirate.send(@association_name).first.name
-    assert_equal 'Privateers Greed', @pirate.send(@association_name).last.name
+    assert_equal "Grace OMalley", @pirate.send(@association_name).first.name
+    assert_equal "Privateers Greed", @pirate.send(@association_name).last.name
   end
 
   def test_should_not_load_association_when_updating_existing_records
     @pirate.reload
-    @pirate.send(association_setter, [{ :id => @child_1.id, :name => 'Grace OMalley' }])
+    @pirate.send(association_setter, [{ id: @child_1.id, name: "Grace OMalley" }])
     assert ! @pirate.send(@association_name).loaded?
 
     @pirate.save
     assert ! @pirate.send(@association_name).loaded?
-    assert_equal 'Grace OMalley', @child_1.reload.name
+    assert_equal "Grace OMalley", @child_1.reload.name
   end
 
   def test_should_not_overwrite_unsaved_updates_when_loading_association
     @pirate.reload
-    @pirate.send(association_setter, [{ :id => @child_1.id, :name => 'Grace OMalley' }])
-    assert_equal 'Grace OMalley', @pirate.send(@association_name).send(:load_target).find { |r| r.id == @child_1.id }.name
+    @pirate.send(association_setter, [{ id: @child_1.id, name: "Grace OMalley" }])
+    assert_equal "Grace OMalley", @pirate.send(@association_name).load_target.find { |r| r.id == @child_1.id }.name
   end
 
   def test_should_preserve_order_when_not_overwriting_unsaved_updates
     @pirate.reload
-    @pirate.send(association_setter, [{ :id => @child_1.id, :name => 'Grace OMalley' }])
-    assert_equal @child_1.id, @pirate.send(@association_name).send(:load_target).first.id
+    @pirate.send(association_setter, [{ id: @child_1.id, name: "Grace OMalley" }])
+    assert_equal @child_1.id, @pirate.send(@association_name).load_target.first.id
   end
 
   def test_should_refresh_saved_records_when_not_overwriting_unsaved_updates
     @pirate.reload
-    record = @pirate.class.reflect_on_association(@association_name).klass.new(name: 'Grace OMalley')
+    record = @pirate.class.reflect_on_association(@association_name).klass.new(name: "Grace OMalley")
     @pirate.send(@association_name) << record
     record.save!
-    @pirate.send(@association_name).last.update!(name: 'Polly')
-    assert_equal 'Polly', @pirate.send(@association_name).send(:load_target).last.name
+    @pirate.send(@association_name).last.update!(name: "Polly")
+    assert_equal "Polly", @pirate.send(@association_name).load_target.last.name
   end
 
   def test_should_not_remove_scheduled_destroys_when_loading_association
     @pirate.reload
-    @pirate.send(association_setter, [{ :id => @child_1.id, :_destroy => '1' }])
-    assert @pirate.send(@association_name).send(:load_target).find { |r| r.id == @child_1.id }.marked_for_destruction?
+    @pirate.send(association_setter, [{ id: @child_1.id, _destroy: "1" }])
+    assert @pirate.send(@association_name).load_target.find { |r| r.id == @child_1.id }.marked_for_destruction?
   end
 
   def test_should_take_a_hash_with_composite_id_keys_and_assign_the_attributes_to_the_associated_models
-    @child_1.stub(:id, 'ABC1X') do
-      @child_2.stub(:id, 'ABC2X') do
+    @child_1.stub(:id, "ABC1X") do
+      @child_2.stub(:id, "ABC2X") do
 
         @pirate.attributes = {
           association_getter => [
-            { :id => @child_1.id, :name => 'Grace OMalley' },
-            { :id => @child_2.id, :name => 'Privateers Greed' }
+            { id: @child_1.id, name: "Grace OMalley" },
+            { id: @child_2.id, name: "Privateers Greed" }
           ]
         }
 
-        assert_equal ['Grace OMalley', 'Privateers Greed'], [@child_1.name, @child_2.name]
+        assert_equal ["Grace OMalley", "Privateers Greed"], [@child_1.name, @child_2.name]
       end
     end
   end
 
   def test_should_raise_RecordNotFound_if_an_id_is_given_but_doesnt_return_a_record
     exception = assert_raise ActiveRecord::RecordNotFound do
-      @pirate.attributes = { association_getter => [{ :id => 1234567890 }] }
+      @pirate.attributes = { association_getter => [{ id: 1234567890 }] }
     end
     assert_equal "Couldn't find #{@child_1.class.name} with ID=1234567890 for Pirate with ID=#{@pirate.id}", exception.message
   end
 
   def test_should_raise_RecordNotFound_if_an_id_belonging_to_a_different_record_is_given
-    other_pirate = Pirate.create! catchphrase: 'Ahoy!'
-    other_child = other_pirate.send(@association_name).create! name: 'Buccaneers Servant'
+    other_pirate = Pirate.create! catchphrase: "Ahoy!"
+    other_child = other_pirate.send(@association_name).create! name: "Buccaneers Servant"
 
     exception = assert_raise ActiveRecord::RecordNotFound do
       @pirate.attributes = { association_getter => [{ id: other_child.id }] }
@@ -702,19 +702,19 @@ module NestedAttributesOnACollectionAssociationTests
   def test_should_automatically_build_new_associated_models_for_each_entry_in_a_hash_where_the_id_is_missing
     @pirate.send(@association_name).destroy_all
     @pirate.reload.attributes = {
-      association_getter => { 'foo' => { :name => 'Grace OMalley' }, 'bar' => { :name => 'Privateers Greed' }}
+      association_getter => { "foo" => { name: "Grace OMalley" }, "bar" => { name: "Privateers Greed" } }
     }
 
     assert !@pirate.send(@association_name).first.persisted?
-    assert_equal 'Grace OMalley', @pirate.send(@association_name).first.name
+    assert_equal "Grace OMalley", @pirate.send(@association_name).first.name
 
     assert !@pirate.send(@association_name).last.persisted?
-    assert_equal 'Privateers Greed', @pirate.send(@association_name).last.name
+    assert_equal "Privateers Greed", @pirate.send(@association_name).last.name
   end
 
   def test_should_not_assign_destroy_key_to_a_record
     assert_nothing_raised do
-      @pirate.send(association_setter, { 'foo' => { '_destroy' => '0' }})
+      @pirate.send(association_setter, "foo" => { "_destroy" => "0" })
     end
   end
 
@@ -722,17 +722,17 @@ module NestedAttributesOnACollectionAssociationTests
     @pirate.send(@association_name).destroy_all
     @pirate.reload.attributes = {
       association_getter => {
-        'foo' => { :name => 'Grace OMalley' },
-        'bar' => { :name => 'Privateers Greed', '_destroy' => '1' }
+        "foo" => { name: "Grace OMalley" },
+        "bar" => { :name => "Privateers Greed", "_destroy" => "1" }
       }
     }
 
     assert_equal 1, @pirate.send(@association_name).length
-    assert_equal 'Grace OMalley', @pirate.send(@association_name).first.name
+    assert_equal "Grace OMalley", @pirate.send(@association_name).first.name
   end
 
   def test_should_ignore_new_associated_records_if_a_reject_if_proc_returns_false
-    @alternate_params[association_getter]['baz'] = {}
+    @alternate_params[association_getter]["baz"] = {}
     assert_no_difference("@pirate.send(@association_name).count") do
       @pirate.attributes = @alternate_params
     end
@@ -740,11 +740,11 @@ module NestedAttributesOnACollectionAssociationTests
 
   def test_should_sort_the_hash_by_the_keys_before_building_new_associated_models
     attributes = {}
-    attributes['123726353'] = { :name => 'Grace OMalley' }
-    attributes['2'] = { :name => 'Privateers Greed' } # 2 is lower then 123726353
+    attributes["123726353"] = { name: "Grace OMalley" }
+    attributes["2"] = { name: "Privateers Greed" } # 2 is lower then 123726353
     @pirate.send(association_setter, attributes)
 
-    assert_equal ['Posideons Killer', 'Killer bandita Dionne', 'Privateers Greed', 'Grace OMalley'].to_set, @pirate.send(@association_name).map(&:name).to_set
+    assert_equal ["Posideons Killer", "Killer bandita Dionne", "Privateers Greed", "Grace OMalley"].to_set, @pirate.send(@association_name).map(&:name).to_set
   end
 
   def test_should_raise_an_argument_error_if_something_else_than_a_hash_is_passed
@@ -754,51 +754,51 @@ module NestedAttributesOnACollectionAssociationTests
     exception = assert_raise ArgumentError do
       @pirate.send(association_setter, "foo")
     end
-    assert_equal 'Hash or Array expected, got String ("foo")', exception.message
+    assert_equal %{Hash or Array expected for attribute `#{@association_name}`, got String ("foo")}, exception.message
   end
 
   def test_should_work_with_update_as_well
-    @pirate.update(catchphrase: 'Arr',
-      association_getter => { 'foo' => { :id => @child_1.id, :name => 'Grace OMalley' }})
+    @pirate.update(catchphrase: "Arr",
+      association_getter => { "foo" => { id: @child_1.id, name: "Grace OMalley" } })
 
-    assert_equal 'Grace OMalley', @child_1.reload.name
+    assert_equal "Grace OMalley", @child_1.reload.name
   end
 
   def test_should_update_existing_records_and_add_new_ones_that_have_no_id
-    @alternate_params[association_getter]['baz'] = { name: 'Buccaneers Servant' }
-    assert_difference('@pirate.send(@association_name).count', +1) do
+    @alternate_params[association_getter]["baz"] = { name: "Buccaneers Servant" }
+    assert_difference("@pirate.send(@association_name).count", +1) do
       @pirate.update @alternate_params
     end
-    assert_equal ['Grace OMalley', 'Privateers Greed', 'Buccaneers Servant'].to_set, @pirate.reload.send(@association_name).map(&:name).to_set
+    assert_equal ["Grace OMalley", "Privateers Greed", "Buccaneers Servant"].to_set, @pirate.reload.send(@association_name).map(&:name).to_set
   end
 
   def test_should_be_possible_to_destroy_a_record
-    ['1', 1, 'true', true].each do |true_variable|
-      record = @pirate.reload.send(@association_name).create!(:name => 'Grace OMalley')
+    ["1", 1, "true", true].each do |true_variable|
+      record = @pirate.reload.send(@association_name).create!(name: "Grace OMalley")
       @pirate.send(association_setter,
-        @alternate_params[association_getter].merge('baz' => { :id => record.id, '_destroy' => true_variable })
+        @alternate_params[association_getter].merge("baz" => { :id => record.id, "_destroy" => true_variable })
       )
 
-      assert_difference('@pirate.send(@association_name).count', -1) do
+      assert_difference("@pirate.send(@association_name).count", -1) do
         @pirate.save
       end
     end
   end
 
   def test_should_not_destroy_the_associated_model_with_a_non_truthy_argument
-    [nil, '', '0', 0, 'false', false].each do |false_variable|
-      @alternate_params[association_getter]['foo']['_destroy'] = false_variable
-      assert_no_difference('@pirate.send(@association_name).count') do
+    [nil, "", "0", 0, "false", false].each do |false_variable|
+      @alternate_params[association_getter]["foo"]["_destroy"] = false_variable
+      assert_no_difference("@pirate.send(@association_name).count") do
         @pirate.update(@alternate_params)
       end
     end
   end
 
   def test_should_not_destroy_the_associated_model_until_the_parent_is_saved
-    assert_no_difference('@pirate.send(@association_name).count') do
-      @pirate.send(association_setter, @alternate_params[association_getter].merge('baz' => { :id => @child_1.id, '_destroy' => true }))
+    assert_no_difference("@pirate.send(@association_name).count") do
+      @pirate.send(association_setter, @alternate_params[association_getter].merge("baz" => { :id => @child_1.id, "_destroy" => true }))
     end
-    assert_difference('@pirate.send(@association_name).count', -1) { @pirate.save }
+    assert_difference("@pirate.send(@association_name).count", -1) { @pirate.save }
   end
 
   def test_should_automatically_enable_autosave_on_the_association
@@ -812,10 +812,10 @@ module NestedAttributesOnACollectionAssociationTests
 
     repair_validations(Interest) do
       Interest.validates_presence_of(:man)
-      assert_difference 'Man.count' do
-        assert_difference 'Interest.count', 2 do
-          man = Man.create!(:name => 'John',
-                            :interests_attributes => [{:topic=>'Cars'}, {:topic=>'Sports'}])
+      assert_difference "Man.count" do
+        assert_difference "Interest.count", 2 do
+          man = Man.create!(name: "John",
+                            interests_attributes: [{ topic: "Cars" }, { topic: "Sports" }])
           assert_equal 2, man.interests.count
         end
       end
@@ -823,7 +823,7 @@ module NestedAttributesOnACollectionAssociationTests
   end
 
   def test_can_use_symbols_as_object_identifier
-    @pirate.attributes = { :parrots_attributes => { :foo => { :name => 'Lovely Day' }, :bar => { :name => 'Blown Away' } } }
+    @pirate.attributes = { parrots_attributes: { foo: { name: "Lovely Day" }, bar: { name: "Blown Away" } } }
     assert_nothing_raised { @pirate.save! }
   end
 
@@ -832,22 +832,22 @@ module NestedAttributesOnACollectionAssociationTests
 
     repair_validations(Interest) do
       Interest.validates_numericality_of(:zine_id)
-      man = Man.create(name: 'John')
-      interest = man.interests.create(topic: 'bar', zine_id: 0)
+      man = Man.create(name: "John")
+      interest = man.interests.create(topic: "bar", zine_id: 0)
       assert interest.save
-      assert !man.update({interests_attributes: { id: interest.id, zine_id: 'foo' }})
+      assert !man.update(interests_attributes: { id: interest.id, zine_id: "foo" })
     end
   end
 
   private
 
-  def association_setter
-    @association_setter ||= "#{@association_name}_attributes=".to_sym
-  end
+    def association_setter
+      @association_setter ||= "#{@association_name}_attributes=".to_sym
+    end
 
-  def association_getter
-    @association_getter ||= "#{@association_name}_attributes".to_sym
-  end
+    def association_getter
+      @association_getter ||= "#{@association_name}_attributes".to_sym
+    end
 end
 
 class TestNestedAttributesOnAHasManyAssociation < ActiveRecord::TestCase
@@ -855,16 +855,16 @@ class TestNestedAttributesOnAHasManyAssociation < ActiveRecord::TestCase
     @association_type = :has_many
     @association_name = :birds
 
-    @pirate = Pirate.create!(:catchphrase => "Don' botharrr talkin' like one, savvy?")
-    @pirate.birds.create!(:name => 'Posideons Killer')
-    @pirate.birds.create!(:name => 'Killer bandita Dionne')
+    @pirate = Pirate.create!(catchphrase: "Don' botharrr talkin' like one, savvy?")
+    @pirate.birds.create!(name: "Posideons Killer")
+    @pirate.birds.create!(name: "Killer bandita Dionne")
 
     @child_1, @child_2 = @pirate.birds
 
     @alternate_params = {
-      :birds_attributes => {
-        'foo' => { :id => @child_1.id, :name => 'Grace OMalley' },
-        'bar' => { :id => @child_2.id, :name => 'Privateers Greed' }
+      birds_attributes: {
+        "foo" => { id: @child_1.id, name: "Grace OMalley" },
+        "bar" => { id: @child_2.id, name: "Privateers Greed" }
       }
     }
   end
@@ -877,16 +877,16 @@ class TestNestedAttributesOnAHasAndBelongsToManyAssociation < ActiveRecord::Test
     @association_type = :has_and_belongs_to_many
     @association_name = :parrots
 
-    @pirate = Pirate.create!(:catchphrase => "Don' botharrr talkin' like one, savvy?")
-    @pirate.parrots.create!(:name => 'Posideons Killer')
-    @pirate.parrots.create!(:name => 'Killer bandita Dionne')
+    @pirate = Pirate.create!(catchphrase: "Don' botharrr talkin' like one, savvy?")
+    @pirate.parrots.create!(name: "Posideons Killer")
+    @pirate.parrots.create!(name: "Killer bandita Dionne")
 
     @child_1, @child_2 = @pirate.parrots
 
     @alternate_params = {
-      :parrots_attributes => {
-        'foo' => { :id => @child_1.id, :name => 'Grace OMalley' },
-        'bar' => { :id => @child_2.id, :name => 'Privateers Greed' }
+      parrots_attributes: {
+        "foo" => { id: @child_1.id, name: "Grace OMalley" },
+        "bar" => { id: @child_2.id, name: "Privateers Greed" }
       }
     }
   end
@@ -896,33 +896,33 @@ end
 
 module NestedAttributesLimitTests
   def teardown
-    Pirate.accepts_nested_attributes_for :parrots, :allow_destroy => true, :reject_if => proc(&:empty?)
+    Pirate.accepts_nested_attributes_for :parrots, allow_destroy: true, reject_if: proc(&:empty?)
   end
 
   def test_limit_with_less_records
-    @pirate.attributes = { :parrots_attributes => { 'foo' => { :name => 'Big Big Love' } } }
-    assert_difference('Parrot.count') { @pirate.save! }
+    @pirate.attributes = { parrots_attributes: { "foo" => { name: "Big Big Love" } } }
+    assert_difference("Parrot.count") { @pirate.save! }
   end
 
   def test_limit_with_number_exact_records
-    @pirate.attributes = { :parrots_attributes => { 'foo' => { :name => 'Lovely Day' }, 'bar' => { :name => 'Blown Away' } } }
-    assert_difference('Parrot.count', 2) { @pirate.save! }
+    @pirate.attributes = { parrots_attributes: { "foo" => { name: "Lovely Day" }, "bar" => { name: "Blown Away" } } }
+    assert_difference("Parrot.count", 2) { @pirate.save! }
   end
 
   def test_limit_with_exceeding_records
     assert_raises(ActiveRecord::NestedAttributes::TooManyRecords) do
-      @pirate.attributes = { :parrots_attributes => { 'foo' => { :name => 'Lovely Day' },
-                                                      'bar' => { :name => 'Blown Away' },
-                                                      'car' => { :name => 'The Happening' }} }
+      @pirate.attributes = { parrots_attributes: { "foo" => { name: "Lovely Day" },
+                                                      "bar" => { name: "Blown Away" },
+                                                      "car" => { name: "The Happening" } } }
     end
   end
 end
 
 class TestNestedAttributesLimitNumeric < ActiveRecord::TestCase
   def setup
-    Pirate.accepts_nested_attributes_for :parrots, :limit => 2
+    Pirate.accepts_nested_attributes_for :parrots, limit: 2
 
-    @pirate = Pirate.create!(:catchphrase => "Don' botharrr talkin' like one, savvy?")
+    @pirate = Pirate.create!(catchphrase: "Don' botharrr talkin' like one, savvy?")
   end
 
   include NestedAttributesLimitTests
@@ -930,9 +930,9 @@ end
 
 class TestNestedAttributesLimitSymbol < ActiveRecord::TestCase
   def setup
-    Pirate.accepts_nested_attributes_for :parrots, :limit => :parrots_limit
+    Pirate.accepts_nested_attributes_for :parrots, limit: :parrots_limit
 
-    @pirate = Pirate.create!(:catchphrase => "Don' botharrr talkin' like one, savvy?", :parrots_limit => 2)
+    @pirate = Pirate.create!(catchphrase: "Don' botharrr talkin' like one, savvy?", parrots_limit: 2)
   end
 
   include NestedAttributesLimitTests
@@ -940,9 +940,9 @@ end
 
 class TestNestedAttributesLimitProc < ActiveRecord::TestCase
   def setup
-    Pirate.accepts_nested_attributes_for :parrots, :limit => proc { 2 }
+    Pirate.accepts_nested_attributes_for :parrots, limit: proc { 2 }
 
-    @pirate = Pirate.create!(:catchphrase => "Don' botharrr talkin' like one, savvy?")
+    @pirate = Pirate.create!(catchphrase: "Don' botharrr talkin' like one, savvy?")
   end
 
   include NestedAttributesLimitTests
@@ -952,45 +952,44 @@ class TestNestedAttributesWithNonStandardPrimaryKeys < ActiveRecord::TestCase
   fixtures :owners, :pets
 
   def setup
-    Owner.accepts_nested_attributes_for :pets, :allow_destroy => true
+    Owner.accepts_nested_attributes_for :pets, allow_destroy: true
 
     @owner = owners(:ashley)
     @pet1, @pet2 = pets(:chew), pets(:mochi)
 
     @params = {
-      :pets_attributes => {
-        '0' => { :id => @pet1.id, :name => 'Foo' },
-        '1' => { :id => @pet2.id, :name => 'Bar' }
+      pets_attributes: {
+        "0" => { id: @pet1.id, name: "Foo" },
+        "1" => { id: @pet2.id, name: "Bar" }
       }
     }
   end
 
   def test_should_update_existing_records_with_non_standard_primary_key
     @owner.update(@params)
-    assert_equal ['Foo', 'Bar'], @owner.pets.map(&:name)
+    assert_equal ["Foo", "Bar"], @owner.pets.map(&:name)
   end
 
   def test_attr_accessor_of_child_should_be_value_provided_during_update
     @owner = owners(:ashley)
     @pet1 = pets(:chew)
-    attributes = {:pets_attributes => { "1"=> { :id => @pet1.id,
-                                                :name => "Foo2",
-                                                :current_user => "John",
-                                                :_destroy=>true }}}
+    attributes = { pets_attributes: { "1" => { id: @pet1.id,
+                                                name: "Foo2",
+                                                current_user: "John",
+                                                _destroy: true } } }
     @owner.update(attributes)
-    assert_equal 'John', Pet.after_destroy_output
+    assert_equal "John", Pet.after_destroy_output
   end
-
 end
 
 class TestHasOneAutosaveAssociationWhichItselfHasAutosaveAssociations < ActiveRecord::TestCase
   self.use_transactional_tests = false unless supports_savepoints?
 
   def setup
-    @pirate = Pirate.create!(:catchphrase => "My baby takes tha mornin' train!")
-    @ship = @pirate.create_ship(:name => "The good ship Dollypop")
-    @part = @ship.parts.create!(:name => "Mast")
-    @trinket = @part.trinkets.create!(:name => "Necklace")
+    @pirate = Pirate.create!(catchphrase: "My baby takes tha mornin' train!")
+    @ship = @pirate.create_ship(name: "The good ship Dollypop")
+    @part = @ship.parts.create!(name: "Mast")
+    @trinket = @part.trinkets.create!(name: "Necklace")
   end
 
   test "when great-grandchild changed in memory, saving parent should save great-grandchild" do
@@ -1000,25 +999,25 @@ class TestHasOneAutosaveAssociationWhichItselfHasAutosaveAssociations < ActiveRe
   end
 
   test "when great-grandchild changed via attributes, saving parent should save great-grandchild" do
-    @pirate.attributes = {:ship_attributes => {:id => @ship.id, :parts_attributes => [{:id => @part.id, :trinkets_attributes => [{:id => @trinket.id, :name => "changed"}]}]}}
+    @pirate.attributes = { ship_attributes: { id: @ship.id, parts_attributes: [{ id: @part.id, trinkets_attributes: [{ id: @trinket.id, name: "changed" }] }] } }
     @pirate.save
     assert_equal "changed", @trinket.reload.name
   end
 
   test "when great-grandchild marked_for_destruction via attributes, saving parent should destroy great-grandchild" do
-    @pirate.attributes = {:ship_attributes => {:id => @ship.id, :parts_attributes => [{:id => @part.id, :trinkets_attributes => [{:id => @trinket.id, :_destroy => true}]}]}}
-    assert_difference('@part.trinkets.count', -1) { @pirate.save }
+    @pirate.attributes = { ship_attributes: { id: @ship.id, parts_attributes: [{ id: @part.id, trinkets_attributes: [{ id: @trinket.id, _destroy: true }] }] } }
+    assert_difference("@part.trinkets.count", -1) { @pirate.save }
   end
 
   test "when great-grandchild added via attributes, saving parent should create great-grandchild" do
-    @pirate.attributes = {:ship_attributes => {:id => @ship.id, :parts_attributes => [{:id => @part.id, :trinkets_attributes => [{:name => "created"}]}]}}
-    assert_difference('@part.trinkets.count', 1) { @pirate.save }
+    @pirate.attributes = { ship_attributes: { id: @ship.id, parts_attributes: [{ id: @part.id, trinkets_attributes: [{ name: "created" }] }] } }
+    assert_difference("@part.trinkets.count", 1) { @pirate.save }
   end
 
   test "when extra records exist for associations, validate (which calls nested_records_changed_for_autosave?) should not load them up" do
     @trinket.name = "changed"
-    Ship.create!(:pirate => @pirate, :name => "The Black Rock")
-    ShipPart.create!(:ship => @ship, :name => "Stern")
+    Ship.create!(pirate: @pirate, name: "The Black Rock")
+    ShipPart.create!(ship: @ship, name: "Stern")
     assert_no_queries { @pirate.valid? }
   end
 end
@@ -1027,27 +1026,27 @@ class TestHasManyAutosaveAssociationWhichItselfHasAutosaveAssociations < ActiveR
   self.use_transactional_tests = false unless supports_savepoints?
 
   def setup
-    @ship = Ship.create!(:name => "The good ship Dollypop")
-    @part = @ship.parts.create!(:name => "Mast")
-    @trinket = @part.trinkets.create!(:name => "Necklace")
+    @ship = Ship.create!(name: "The good ship Dollypop")
+    @part = @ship.parts.create!(name: "Mast")
+    @trinket = @part.trinkets.create!(name: "Necklace")
   end
 
   test "if association is not loaded and association record is saved and then in memory record attributes should be saved" do
-    @ship.parts_attributes=[{:id => @part.id,:name =>'Deck'}]
+    @ship.parts_attributes = [{ id: @part.id, name: "Deck" }]
     assert_equal 1, @ship.association(:parts).target.size
-    assert_equal 'Deck', @ship.parts[0].name
+    assert_equal "Deck", @ship.parts[0].name
   end
 
   test "if association is not loaded and child doesn't change and I am saving a grandchild then in memory record should be used" do
-    @ship.parts_attributes=[{:id => @part.id,:trinkets_attributes =>[{:id => @trinket.id, :name => 'Ruby'}]}]
+    @ship.parts_attributes = [{ id: @part.id, trinkets_attributes: [{ id: @trinket.id, name: "Ruby" }] }]
     assert_equal 1, @ship.association(:parts).target.size
-    assert_equal 'Mast', @ship.parts[0].name
+    assert_equal "Mast", @ship.parts[0].name
     assert_no_difference("@ship.parts[0].association(:trinkets).target.size") do
       @ship.parts[0].association(:trinkets).target.size
     end
-    assert_equal 'Ruby', @ship.parts[0].trinkets[0].name
+    assert_equal "Ruby", @ship.parts[0].trinkets[0].name
     @ship.save
-    assert_equal 'Ruby', @ship.parts[0].trinkets[0].name
+    assert_equal "Ruby", @ship.parts[0].trinkets[0].name
   end
 
   test "when grandchild changed in memory, saving parent should save grandchild" do
@@ -1057,25 +1056,25 @@ class TestHasManyAutosaveAssociationWhichItselfHasAutosaveAssociations < ActiveR
   end
 
   test "when grandchild changed via attributes, saving parent should save grandchild" do
-    @ship.attributes = {:parts_attributes => [{:id => @part.id, :trinkets_attributes => [{:id => @trinket.id, :name => "changed"}]}]}
+    @ship.attributes = { parts_attributes: [{ id: @part.id, trinkets_attributes: [{ id: @trinket.id, name: "changed" }] }] }
     @ship.save
     assert_equal "changed", @trinket.reload.name
   end
 
   test "when grandchild marked_for_destruction via attributes, saving parent should destroy grandchild" do
-    @ship.attributes = {:parts_attributes => [{:id => @part.id, :trinkets_attributes => [{:id => @trinket.id, :_destroy => true}]}]}
-    assert_difference('@part.trinkets.count', -1) { @ship.save }
+    @ship.attributes = { parts_attributes: [{ id: @part.id, trinkets_attributes: [{ id: @trinket.id, _destroy: true }] }] }
+    assert_difference("@part.trinkets.count", -1) { @ship.save }
   end
 
   test "when grandchild added via attributes, saving parent should create grandchild" do
-    @ship.attributes = {:parts_attributes => [{:id => @part.id, :trinkets_attributes => [{:name => "created"}]}]}
-    assert_difference('@part.trinkets.count', 1) { @ship.save }
+    @ship.attributes = { parts_attributes: [{ id: @part.id, trinkets_attributes: [{ name: "created" }] }] }
+    assert_difference("@part.trinkets.count", 1) { @ship.save }
   end
 
   test "when extra records exist for associations, validate (which calls nested_records_changed_for_autosave?) should not load them up" do
     @trinket.name = "changed"
-    Ship.create!(:name => "The Black Rock")
-    ShipPart.create!(:ship => @ship, :name => "Stern")
+    Ship.create!(name: "The Black Rock")
+    ShipPart.create!(ship: @ship, name: "Stern")
     assert_no_queries { @ship.valid? }
   end
 
diff --git a/activerecord/test/cases/nested_attributes_with_callbacks_test.rb b/activerecord/test/cases/nested_attributes_with_callbacks_test.rb
index 43a69928b6..f04c68b08f 100644
--- a/activerecord/test/cases/nested_attributes_with_callbacks_test.rb
+++ b/activerecord/test/cases/nested_attributes_with_callbacks_test.rb
@@ -1,27 +1,29 @@
+# frozen_string_literal: true
+
 require "cases/helper"
 require "models/pirate"
 require "models/bird"
 
 class NestedAttributesWithCallbacksTest < ActiveRecord::TestCase
   Pirate.has_many(:birds_with_add_load,
-                  :class_name => "Bird",
-                  :before_add => proc { |p,b|
+                  class_name: "Bird",
+                  before_add: proc { |p, b|
                     @@add_callback_called << b
                     p.birds_with_add_load.to_a
                   })
   Pirate.has_many(:birds_with_add,
-                  :class_name => "Bird",
-                  :before_add => proc { |p,b| @@add_callback_called << b })
+                  class_name: "Bird",
+                  before_add: proc { |p, b| @@add_callback_called << b })
 
   Pirate.accepts_nested_attributes_for(:birds_with_add_load,
                                        :birds_with_add,
-                                       :allow_destroy => true)
+                                       allow_destroy: true)
 
   def setup
     @@add_callback_called = []
     @pirate = Pirate.new.tap do |pirate|
       pirate.catchphrase = "Don't call me!"
-      pirate.birds_attributes = [{:name => 'Bird1'},{:name => 'Bird2'}]
+      pirate.birds_attributes = [{ name: "Bird1" }, { name: "Bird2" }]
       pirate.save!
     end
     @birds = @pirate.birds.to_a
@@ -37,7 +39,7 @@ class NestedAttributesWithCallbacksTest < ActiveRecord::TestCase
 
   def existing_birds_attributes
     @birds.map do |bird|
-      bird.attributes.slice("id","name")
+      bird.attributes.slice("id", "name")
     end
   end
 
@@ -46,17 +48,17 @@ class NestedAttributesWithCallbacksTest < ActiveRecord::TestCase
   end
 
   def new_bird_attributes
-     [{'name' => "New Bird"}]
+    [{ "name" => "New Bird" }]
   end
 
   def destroy_bird_attributes
-    [{'id' => bird_to_destroy.id.to_s, "_destroy" => true}]
+    [{ "id" => bird_to_destroy.id.to_s, "_destroy" => true }]
   end
 
   def update_new_and_destroy_bird_attributes
-    [{'id' => @birds[0].id.to_s, 'name' => 'New Name'},
-     {'name' => "New Bird"},
-     {'id' => bird_to_destroy.id.to_s, "_destroy" => true}]
+    [{ "id" => @birds[0].id.to_s, "name" => "New Name" },
+     { "name" => "New Bird" },
+     { "id" => bird_to_destroy.id.to_s, "_destroy" => true }]
   end
 
   # Characterizing when :before_add callback is called
@@ -120,14 +122,14 @@ class NestedAttributesWithCallbacksTest < ActiveRecord::TestCase
     assert_assignment_affects_records_in_target(:birds_with_add)
   end
 
-  test("Assignment updates records in target when not loaded" +
+  test("Assignment updates records in target when not loaded" \
        " and callback loads target") do
     assert_not @pirate.birds_with_add_load.loaded?
     @pirate.birds_with_add_load_attributes = update_new_and_destroy_bird_attributes
     assert_assignment_affects_records_in_target(:birds_with_add_load)
   end
 
-  test("Assignment updates records in target when loaded" +
+  test("Assignment updates records in target when loaded" \
        " and callback loads target") do
     @pirate.birds_with_add_load.load_target
     @pirate.birds_with_add_load_attributes = update_new_and_destroy_bird_attributes
@@ -136,9 +138,9 @@ class NestedAttributesWithCallbacksTest < ActiveRecord::TestCase
 
   def assert_assignment_affects_records_in_target(association_name)
     association = @pirate.send(association_name)
-    assert association.detect {|b| b == bird_to_update }.name_changed?,
-      'Update record not updated'
-    assert association.detect {|b| b == bird_to_destroy }.marked_for_destruction?,
-      'Destroy record not marked for destruction'
+    assert association.detect { |b| b == bird_to_update }.name_changed?,
+      "Update record not updated"
+    assert association.detect { |b| b == bird_to_destroy }.marked_for_destruction?,
+      "Destroy record not marked for destruction"
   end
 end
diff --git a/activerecord/test/cases/null_relation_test.rb b/activerecord/test/cases/null_relation_test.rb
new file mode 100644
index 0000000000..17527568f8
--- /dev/null
+++ b/activerecord/test/cases/null_relation_test.rb
@@ -0,0 +1,84 @@
+# frozen_string_literal: true
+
+require "cases/helper"
+require "models/developer"
+require "models/comment"
+require "models/post"
+require "models/topic"
+
+class NullRelationTest < ActiveRecord::TestCase
+  fixtures :posts, :comments
+
+  def test_none
+    assert_no_queries(ignore_none: false) do
+      assert_equal [], Developer.none
+      assert_equal [], Developer.all.none
+    end
+  end
+
+  def test_none_chainable
+    assert_no_queries(ignore_none: false) do
+      assert_equal [], Developer.none.where(name: "David")
+    end
+  end
+
+  def test_none_chainable_to_existing_scope_extension_method
+    assert_no_queries(ignore_none: false) do
+      assert_equal 1, Topic.anonymous_extension.none.one
+    end
+  end
+
+  def test_none_chained_to_methods_firing_queries_straight_to_db
+    assert_no_queries(ignore_none: false) do
+      assert_equal [],    Developer.none.pluck(:id, :name)
+      assert_equal 0,     Developer.none.delete_all
+      assert_equal 0,     Developer.none.update_all(name: "David")
+      assert_equal 0,     Developer.none.delete(1)
+      assert_equal false, Developer.none.exists?(1)
+    end
+  end
+
+  def test_null_relation_content_size_methods
+    assert_no_queries(ignore_none: false) do
+      assert_equal 0,     Developer.none.size
+      assert_equal 0,     Developer.none.count
+      assert_equal true,  Developer.none.empty?
+      assert_equal true,  Developer.none.none?
+      assert_equal false, Developer.none.any?
+      assert_equal false, Developer.none.one?
+      assert_equal false, Developer.none.many?
+    end
+  end
+
+  def test_null_relation_metadata_methods
+    assert_equal "", Developer.none.to_sql
+    assert_equal({}, Developer.none.where_values_hash)
+  end
+
+  def test_null_relation_where_values_hash
+    assert_equal({ "salary" => 100_000 }, Developer.none.where(salary: 100_000).where_values_hash)
+  end
+
+  [:count, :sum].each do |method|
+    define_method "test_null_relation_#{method}" do
+      assert_no_queries(ignore_none: false) do
+        assert_equal 0, Comment.none.public_send(method, :id)
+        assert_equal Hash.new, Comment.none.group(:post_id).public_send(method, :id)
+      end
+    end
+  end
+
+  [:average, :minimum, :maximum].each do |method|
+    define_method "test_null_relation_#{method}" do
+      assert_no_queries(ignore_none: false) do
+        assert_nil Comment.none.public_send(method, :id)
+        assert_equal Hash.new, Comment.none.group(:post_id).public_send(method, :id)
+      end
+    end
+  end
+
+  def test_null_relation_in_where_condition
+    assert_operator Comment.count, :>, 0 # precondition, make sure there are comments.
+    assert_equal 0, Comment.where(post_id: Post.none).count
+  end
+end
diff --git a/activerecord/test/cases/numeric_data_test.rb b/activerecord/test/cases/numeric_data_test.rb
new file mode 100644
index 0000000000..f917c8f727
--- /dev/null
+++ b/activerecord/test/cases/numeric_data_test.rb
@@ -0,0 +1,73 @@
+# frozen_string_literal: true
+
+require "cases/helper"
+require "models/numeric_data"
+
+class NumericDataTest < ActiveRecord::TestCase
+  def test_big_decimal_conditions
+    m = NumericData.new(
+      bank_balance: 1586.43,
+      big_bank_balance: BigDecimal("1000234000567.95"),
+      world_population: 6000000000,
+      my_house_population: 3
+    )
+    assert m.save
+    assert_equal 0, NumericData.where("bank_balance > ?", 2000.0).count
+  end
+
+  def test_numeric_fields
+    m = NumericData.new(
+      bank_balance: 1586.43,
+      big_bank_balance: BigDecimal("1000234000567.95"),
+      world_population: 6000000000,
+      my_house_population: 3
+    )
+    assert m.save
+
+    m1 = NumericData.find(m.id)
+    assert_not_nil m1
+
+    # As with migration_test.rb, we should make world_population >= 2**62
+    # to cover 64-bit platforms and test it is a Bignum, but the main thing
+    # is that it's an Integer.
+    assert_kind_of Integer, m1.world_population
+    assert_equal 6000000000, m1.world_population
+
+    assert_kind_of Integer, m1.my_house_population
+    assert_equal 3, m1.my_house_population
+
+    assert_kind_of BigDecimal, m1.bank_balance
+    assert_equal BigDecimal("1586.43"), m1.bank_balance
+
+    assert_kind_of BigDecimal, m1.big_bank_balance
+    assert_equal BigDecimal("1000234000567.95"), m1.big_bank_balance
+  end
+
+  def test_numeric_fields_with_scale
+    m = NumericData.new(
+      bank_balance: 1586.43122334,
+      big_bank_balance: BigDecimal("234000567.952344"),
+      world_population: 6000000000,
+      my_house_population: 3
+    )
+    assert m.save
+
+    m1 = NumericData.find(m.id)
+    assert_not_nil m1
+
+    # As with migration_test.rb, we should make world_population >= 2**62
+    # to cover 64-bit platforms and test it is a Bignum, but the main thing
+    # is that it's an Integer.
+    assert_kind_of Integer, m1.world_population
+    assert_equal 6000000000, m1.world_population
+
+    assert_kind_of Integer, m1.my_house_population
+    assert_equal 3, m1.my_house_population
+
+    assert_kind_of BigDecimal, m1.bank_balance
+    assert_equal BigDecimal("1586.43"), m1.bank_balance
+
+    assert_kind_of BigDecimal, m1.big_bank_balance
+    assert_equal BigDecimal("234000567.95"), m1.big_bank_balance
+  end
+end
diff --git a/activerecord/test/cases/persistence_test.rb b/activerecord/test/cases/persistence_test.rb
index 56092aaa0c..0fa8ea212f 100644
--- a/activerecord/test/cases/persistence_test.rb
+++ b/activerecord/test/cases/persistence_test.rb
@@ -1,30 +1,32 @@
+# frozen_string_literal: true
+
 require "cases/helper"
-require 'models/aircraft'
-require 'models/post'
-require 'models/comment'
-require 'models/author'
-require 'models/topic'
-require 'models/reply'
-require 'models/category'
-require 'models/company'
-require 'models/developer'
-require 'models/computer'
-require 'models/project'
-require 'models/minimalistic'
-require 'models/warehouse_thing'
-require 'models/parrot'
-require 'models/minivan'
-require 'models/owner'
-require 'models/person'
-require 'models/pet'
-require 'models/ship'
-require 'models/toy'
-require 'models/admin'
-require 'models/admin/user'
-require 'rexml/document'
+require "models/aircraft"
+require "models/post"
+require "models/comment"
+require "models/author"
+require "models/topic"
+require "models/reply"
+require "models/category"
+require "models/company"
+require "models/developer"
+require "models/computer"
+require "models/project"
+require "models/minimalistic"
+require "models/warehouse_thing"
+require "models/parrot"
+require "models/minivan"
+require "models/owner"
+require "models/person"
+require "models/pet"
+require "models/ship"
+require "models/toy"
+require "models/admin"
+require "models/admin/user"
+require "rexml/document"
 
 class PersistenceTest < ActiveRecord::TestCase
-  fixtures :topics, :companies, :developers, :projects, :computers, :accounts, :minimalistics, 'warehouse-things', :authors, :author_addresses, :categorizations, :categories, :posts, :minivans, :pets, :toys
+  fixtures :topics, :companies, :developers, :projects, :computers, :accounts, :minimalistics, "warehouse-things", :authors, :author_addresses, :categorizations, :categories, :posts, :minivans, :pets, :toys
 
   # Oracle UPDATE does not support ORDER BY
   unless current_adapter?(:OracleAdapter)
@@ -39,31 +41,60 @@ class PersistenceTest < ActiveRecord::TestCase
       assert_equal authors(:david).id + 1, authors(:mary).id # make sure there is going to be a duplicate PK error
       test_update_with_order_succeeds = lambda do |order|
         begin
-          Author.order(order).update_all('id = id + 1')
+          Author.order(order).update_all("id = id + 1")
         rescue ActiveRecord::ActiveRecordError
           false
         end
       end
 
-      if test_update_with_order_succeeds.call('id DESC')
-        assert !test_update_with_order_succeeds.call('id ASC') # test that this wasn't a fluke and using an incorrect order results in an exception
+      if test_update_with_order_succeeds.call("id DESC")
+        assert !test_update_with_order_succeeds.call("id ASC") # test that this wasn't a fluke and using an incorrect order results in an exception
       else
         # test that we're failing because the current Arel's engine doesn't support UPDATE ORDER BY queries is using subselects instead
-        assert_sql(/\AUPDATE .+ \(SELECT .* ORDER BY id DESC\)\Z/i) do
-          test_update_with_order_succeeds.call('id DESC')
+        assert_sql(/\AUPDATE .+ \(SELECT .* ORDER BY id DESC\)\z/i) do
+          test_update_with_order_succeeds.call("id DESC")
         end
       end
     end
 
     def test_update_all_with_order_and_limit_updates_subset_only
       author = authors(:david)
-      assert_nothing_raised do
-        assert_equal 1, author.posts_sorted_by_id_limited.size
-        assert_equal 2, author.posts_sorted_by_id_limited.limit(2).to_a.size
-        assert_equal 1, author.posts_sorted_by_id_limited.update_all([ "body = ?", "bulk update!" ])
-        assert_equal "bulk update!", posts(:welcome).body
-        assert_not_equal "bulk update!", posts(:thinking).body
-      end
+      limited_posts = author.posts_sorted_by_id_limited
+      assert_equal 1, limited_posts.size
+      assert_equal 2, limited_posts.limit(2).size
+      assert_equal 1, limited_posts.update_all([ "body = ?", "bulk update!" ])
+      assert_equal "bulk update!", posts(:welcome).body
+      assert_not_equal "bulk update!", posts(:thinking).body
+    end
+
+    def test_update_all_with_order_and_limit_and_offset_updates_subset_only
+      author = authors(:david)
+      limited_posts = author.posts_sorted_by_id_limited.offset(1)
+      assert_equal 1, limited_posts.size
+      assert_equal 2, limited_posts.limit(2).size
+      assert_equal 1, limited_posts.update_all([ "body = ?", "bulk update!" ])
+      assert_equal "bulk update!", posts(:thinking).body
+      assert_not_equal "bulk update!", posts(:welcome).body
+    end
+
+    def test_delete_all_with_order_and_limit_deletes_subset_only
+      author = authors(:david)
+      limited_posts = Post.where(author: author).order(:id).limit(1)
+      assert_equal 1, limited_posts.size
+      assert_equal 2, limited_posts.limit(2).size
+      assert_equal 1, limited_posts.delete_all
+      assert_raise(ActiveRecord::RecordNotFound) { posts(:welcome) }
+      assert posts(:thinking)
+    end
+
+    def test_delete_all_with_order_and_limit_and_offset_deletes_subset_only
+      author = authors(:david)
+      limited_posts = Post.where(author: author).order(:id).limit(1).offset(1)
+      assert_equal 1, limited_posts.size
+      assert_equal 2, limited_posts.limit(2).size
+      assert_equal 1, limited_posts.delete_all
+      assert_raise(ActiveRecord::RecordNotFound) { posts(:thinking) }
+      assert posts(:welcome)
     end
   end
 
@@ -71,11 +102,43 @@ class PersistenceTest < ActiveRecord::TestCase
     topic_data = { 1 => { "content" => "1 updated" }, 2 => { "content" => "2 updated" } }
     updated = Topic.update(topic_data.keys, topic_data.values)
 
-    assert_equal 2, updated.size
+    assert_equal [1, 2], updated.map(&:id)
+    assert_equal "1 updated", Topic.find(1).content
+    assert_equal "2 updated", Topic.find(2).content
+  end
+
+  def test_update_many_with_duplicated_ids
+    updated = Topic.update([1, 1, 2], [
+      { "content" => "1 duplicated" }, { "content" => "1 updated" }, { "content" => "2 updated" }
+    ])
+
+    assert_equal [1, 1, 2], updated.map(&:id)
     assert_equal "1 updated", Topic.find(1).content
     assert_equal "2 updated", Topic.find(2).content
   end
 
+  def test_update_many_with_invalid_id
+    topic_data = { 1 => { "content" => "1 updated" }, 2 => { "content" => "2 updated" }, 99999 => {} }
+
+    assert_raise(ActiveRecord::RecordNotFound) do
+      Topic.update(topic_data.keys, topic_data.values)
+    end
+
+    assert_not_equal "1 updated", Topic.find(1).content
+    assert_not_equal "2 updated", Topic.find(2).content
+  end
+
+  def test_class_level_update_is_affected_by_scoping
+    topic_data = { 1 => { "content" => "1 updated" }, 2 => { "content" => "2 updated" } }
+
+    assert_raise(ActiveRecord::RecordNotFound) do
+      Topic.where("1=0").scoping { Topic.update(topic_data.keys, topic_data.values) }
+    end
+
+    assert_not_equal "1 updated", Topic.find(1).content
+    assert_not_equal "2 updated", Topic.find(2).content
+  end
+
   def test_delete_all
     assert Topic.count > 0
 
@@ -83,19 +146,31 @@ class PersistenceTest < ActiveRecord::TestCase
   end
 
   def test_delete_all_with_joins_and_where_part_is_hash
-    where_args = {:toys => {:name => 'Bone'}}
-    count = Pet.joins(:toys).where(where_args).count
+    pets = Pet.joins(:toys).where(toys: { name: "Bone" })
 
-    assert_equal count, 1
-    assert_equal count, Pet.joins(:toys).where(where_args).delete_all
+    assert_equal true, pets.exists?
+    assert_equal pets.count, pets.delete_all
   end
 
   def test_delete_all_with_joins_and_where_part_is_not_hash
-    where_args = ['toys.name = ?', 'Bone']
-    count = Pet.joins(:toys).where(where_args).count
+    pets = Pet.joins(:toys).where("toys.name = ?", "Bone")
+
+    assert_equal true, pets.exists?
+    assert_equal pets.count, pets.delete_all
+  end
 
-    assert_equal count, 1
-    assert_equal count, Pet.joins(:toys).where(where_args).delete_all
+  def test_delete_all_with_left_joins
+    pets = Pet.left_joins(:toys).where(toys: { name: "Bone" })
+
+    assert_equal true, pets.exists?
+    assert_equal pets.count, pets.delete_all
+  end
+
+  def test_delete_all_with_includes
+    pets = Pet.includes(:toys).where(toys: { name: "Bone" })
+
+    assert_equal true, pets.exists?
+    assert_equal pets.count, pets.delete_all
   end
 
   def test_increment_attribute
@@ -131,12 +206,20 @@ class PersistenceTest < ActiveRecord::TestCase
     assert_equal initial_credit + 2, a1.reload.credit_limit
   end
 
+  def test_increment_updates_timestamps
+    topic = topics(:first)
+    topic.update_columns(updated_at: 5.minutes.ago)
+    previous_updated_at = topic.updated_at
+    topic.increment!(:replies_count, touch: true)
+    assert_operator previous_updated_at, :<, topic.reload.updated_at
+  end
+
   def test_destroy_all
     conditions = "author_name = 'Mary'"
-    topics_by_mary = Topic.all.merge!(:where => conditions, :order => 'id').to_a
+    topics_by_mary = Topic.all.merge!(where: conditions, order: "id").to_a
     assert ! topics_by_mary.empty?
 
-    assert_difference('Topic.count', -topics_by_mary.size) do
+    assert_difference("Topic.count", -topics_by_mary.size) do
       destroyed = Topic.where(conditions).destroy_all.sort_by(&:id)
       assert_equal topics_by_mary, destroyed
       assert destroyed.all?(&:frozen?), "destroyed topics should be frozen"
@@ -144,22 +227,32 @@ class PersistenceTest < ActiveRecord::TestCase
   end
 
   def test_destroy_many
-    clients = Client.all.merge!(:order => 'id').find([2, 3])
+    clients = Client.find([2, 3])
 
-    assert_difference('Client.count', -2) do
-      destroyed = Client.destroy([2, 3]).sort_by(&:id)
+    assert_difference("Client.count", -2) do
+      destroyed = Client.destroy([2, 3])
       assert_equal clients, destroyed
       assert destroyed.all?(&:frozen?), "destroyed clients should be frozen"
     end
   end
 
+  def test_destroy_many_with_invalid_id
+    clients = Client.find([2, 3])
+
+    assert_raise(ActiveRecord::RecordNotFound) do
+      Client.destroy([2, 3, 99999])
+    end
+
+    assert_equal clients, Client.find([2, 3])
+  end
+
   def test_becomes
     assert_kind_of Reply, topics(:first).becomes(Reply)
     assert_equal "The First Topic", topics(:first).becomes(Reply).title
   end
 
   def test_becomes_includes_errors
-    company = Company.new(:name => nil)
+    company = Company.new(name: nil)
     assert !company.valid?
     original_errors = company.errors
     client = company.becomes(Client)
@@ -170,7 +263,7 @@ class PersistenceTest < ActiveRecord::TestCase
     child_class = Class.new(Admin::User) do
       store_accessor :settings, :foo
 
-      def self.name; 'Admin::ChildUser'; end
+      def self.name; "Admin::ChildUser"; end
     end
 
     admin = Admin::User.new
@@ -222,6 +315,14 @@ class PersistenceTest < ActiveRecord::TestCase
     assert_equal 41, accounts(:signals37, :reload).credit_limit
   end
 
+  def test_decrement_updates_timestamps
+    topic = topics(:first)
+    topic.update_columns(updated_at: 5.minutes.ago)
+    previous_updated_at = topic.updated_at
+    topic.decrement!(:replies_count, touch: true)
+    assert_operator previous_updated_at, :<, topic.reload.updated_at
+  end
+
   def test_create
     topic = Topic.new
     topic.title = "New Topic"
@@ -231,7 +332,7 @@ class PersistenceTest < ActiveRecord::TestCase
   end
 
   def test_save!
-    topic = Topic.new(:title => "New Topic")
+    topic = Topic.new(title: "New Topic")
     assert topic.save!
 
     reply = WrongReply.new
@@ -261,7 +362,7 @@ class PersistenceTest < ActiveRecord::TestCase
   end
 
   def test_save_for_record_with_only_primary_key_that_is_provided
-    assert_nothing_raised { Minimalistic.create!(:id => 2) }
+    assert_nothing_raised { Minimalistic.create!(id: 2) }
   end
 
   def test_save_with_duping_of_destroyed_object
@@ -281,12 +382,13 @@ class PersistenceTest < ActiveRecord::TestCase
 
   def test_create_columns_not_equal_attributes
     topic = Topic.instantiate(
-      'attributes' => {
-        'title'          => 'Another New Topic',
-        'does_not_exist' => 'test'
-      }
+      "title"          => "Another New Topic",
+      "does_not_exist" => "test"
     )
+    topic = topic.dup # reset @new_record
     assert_nothing_raised { topic.save }
+    assert topic.persisted?
+    assert_equal "Another New Topic", topic.reload.title
   end
 
   def test_create_through_factory_with_block
@@ -330,9 +432,11 @@ class PersistenceTest < ActiveRecord::TestCase
     topic.title = "Still another topic"
     topic.save
 
-    topic_reloaded = Topic.instantiate(topic.attributes.merge('does_not_exist' => 'test'))
-    topic_reloaded.title = 'A New Topic'
+    topic_reloaded = Topic.instantiate(topic.attributes.merge("does_not_exist" => "test"))
+    topic_reloaded.title = "A New Topic"
     assert_nothing_raised { topic_reloaded.save }
+    assert topic_reloaded.persisted?
+    assert_equal "A New Topic", topic_reloaded.reload.title
   end
 
   def test_update_for_record_with_only_primary_key
@@ -371,7 +475,7 @@ class PersistenceTest < ActiveRecord::TestCase
 
   def test_update_after_create
     klass = Class.new(Topic) do
-      def self.name; 'Topic'; end
+      def self.name; "Topic"; end
       after_create do
         update_attribute("author_name", "David")
       end
@@ -387,24 +491,24 @@ class PersistenceTest < ActiveRecord::TestCase
 
   def test_update_attribute_does_not_run_sql_if_attribute_is_not_changed
     klass = Class.new(Topic) do
-      def self.name; 'Topic'; end
+      def self.name; "Topic"; end
     end
-    topic = klass.create(title: 'Another New Topic')
+    topic = klass.create(title: "Another New Topic")
     assert_queries(0) do
-      topic.update_attribute(:title, 'Another New Topic')
+      assert topic.update_attribute(:title, "Another New Topic")
     end
   end
 
   def test_update_does_not_run_sql_if_record_has_not_changed
-    topic = Topic.create(title: 'Another New Topic')
-    assert_queries(0) { topic.update(title: 'Another New Topic') }
-    assert_queries(0) { topic.update_attributes(title: 'Another New Topic') }
+    topic = Topic.create(title: "Another New Topic")
+    assert_queries(0) { assert topic.update(title: "Another New Topic") }
+    assert_queries(0) { assert topic.update_attributes(title: "Another New Topic") }
   end
 
   def test_delete
     topic = Topic.find(1)
-    assert_equal topic, topic.delete, 'topic.delete did not return self'
-    assert topic.frozen?, 'topic not frozen after delete'
+    assert_equal topic, topic.delete, "topic.delete did not return self"
+    assert topic.frozen?, "topic not frozen after delete"
     assert_raise(ActiveRecord::RecordNotFound) { Topic.find(topic.id) }
   end
 
@@ -413,48 +517,84 @@ class PersistenceTest < ActiveRecord::TestCase
     assert_not_nil Topic.find(2)
   end
 
+  def test_delete_isnt_affected_by_scoping
+    topic = Topic.find(1)
+    assert_difference("Topic.count", -1) do
+      Topic.where("1=0").scoping { topic.delete }
+    end
+  end
+
   def test_destroy
     topic = Topic.find(1)
-    assert_equal topic, topic.destroy, 'topic.destroy did not return self'
-    assert topic.frozen?, 'topic not frozen after destroy'
+    assert_equal topic, topic.destroy, "topic.destroy did not return self"
+    assert topic.frozen?, "topic not frozen after destroy"
     assert_raise(ActiveRecord::RecordNotFound) { Topic.find(topic.id) }
   end
 
   def test_destroy!
     topic = Topic.find(1)
-    assert_equal topic, topic.destroy!, 'topic.destroy! did not return self'
-    assert topic.frozen?, 'topic not frozen after destroy!'
+    assert_equal topic, topic.destroy!, "topic.destroy! did not return self"
+    assert topic.frozen?, "topic not frozen after destroy!"
     assert_raise(ActiveRecord::RecordNotFound) { Topic.find(topic.id) }
   end
 
-  def test_record_not_found_exception
+  def test_find_raises_record_not_found_exception
     assert_raise(ActiveRecord::RecordNotFound) { Topic.find(99999) }
   end
 
+  def test_update_raises_record_not_found_exception
+    assert_raise(ActiveRecord::RecordNotFound) { Topic.update(99999, approved: true) }
+  end
+
+  def test_destroy_raises_record_not_found_exception
+    assert_raise(ActiveRecord::RecordNotFound) { Topic.destroy(99999) }
+  end
+
   def test_update_all
     assert_equal Topic.count, Topic.update_all("content = 'bulk updated!'")
     assert_equal "bulk updated!", Topic.find(1).content
     assert_equal "bulk updated!", Topic.find(2).content
 
-    assert_equal Topic.count, Topic.update_all(['content = ?', 'bulk updated again!'])
+    assert_equal Topic.count, Topic.update_all(["content = ?", "bulk updated again!"])
     assert_equal "bulk updated again!", Topic.find(1).content
     assert_equal "bulk updated again!", Topic.find(2).content
 
-    assert_equal Topic.count, Topic.update_all(['content = ?', nil])
+    assert_equal Topic.count, Topic.update_all(["content = ?", nil])
     assert_nil Topic.find(1).content
   end
 
   def test_update_all_with_hash
     assert_not_nil Topic.find(1).last_read
-    assert_equal Topic.count, Topic.update_all(:content => 'bulk updated with hash!', :last_read => nil)
+    assert_equal Topic.count, Topic.update_all(content: "bulk updated with hash!", last_read: nil)
     assert_equal "bulk updated with hash!", Topic.find(1).content
     assert_equal "bulk updated with hash!", Topic.find(2).content
     assert_nil Topic.find(1).last_read
     assert_nil Topic.find(2).last_read
   end
 
+  def test_update_all_with_joins
+    pets = Pet.joins(:toys).where(toys: { name: "Bone" })
+
+    assert_equal true, pets.exists?
+    assert_equal pets.count, pets.update_all(name: "Bob")
+  end
+
+  def test_update_all_with_left_joins
+    pets = Pet.left_joins(:toys).where(toys: { name: "Bone" })
+
+    assert_equal true, pets.exists?
+    assert_equal pets.count, pets.update_all(name: "Bob")
+  end
+
+  def test_update_all_with_includes
+    pets = Pet.includes(:toys).where(toys: { name: "Bone" })
+
+    assert_equal true, pets.exists?
+    assert_equal pets.count, pets.update_all(name: "Bob")
+  end
+
   def test_update_all_with_non_standard_table_name
-    assert_equal 1, WarehouseThing.where(id: 1).update_all(['value = ?', 0])
+    assert_equal 1, WarehouseThing.where(id: 1).update_all(["value = ?", 0])
     assert_equal 0, WarehouseThing.find(1).value
   end
 
@@ -493,23 +633,26 @@ class PersistenceTest < ActiveRecord::TestCase
 
     Topic.find(1).update_attribute(:approved, false)
     assert !Topic.find(1).approved?
+
+    Topic.find(1).update_attribute(:change_approved_before_save, true)
+    assert Topic.find(1).approved?
   end
 
   def test_update_attribute_for_readonly_attribute
-    minivan = Minivan.find('m1')
-    assert_raises(ActiveRecord::ActiveRecordError) { minivan.update_attribute(:color, 'black') }
+    minivan = Minivan.find("m1")
+    assert_raises(ActiveRecord::ActiveRecordError) { minivan.update_attribute(:color, "black") }
   end
 
   def test_update_attribute_with_one_updated
     t = Topic.first
-    t.update_attribute(:title, 'super_title')
-    assert_equal 'super_title', t.title
+    t.update_attribute(:title, "super_title")
+    assert_equal "super_title", t.title
     assert !t.changed?, "topic should not have changed"
     assert !t.title_changed?, "title should not have changed"
-    assert_nil t.title_change, 'title change should be nil'
+    assert_nil t.title_change, "title change should be nil"
 
     t.reload
-    assert_equal 'super_title', t.title
+    assert_equal "super_title", t.title
   end
 
   def test_update_attribute_for_updated_at_on
@@ -569,17 +712,17 @@ class PersistenceTest < ActiveRecord::TestCase
   end
 
   def test_update_column_with_model_having_primary_key_other_than_id
-    minivan = Minivan.find('m1')
-    new_name = 'sebavan'
+    minivan = Minivan.find("m1")
+    new_name = "sebavan"
 
     minivan.update_column(:name, new_name)
     assert_equal new_name, minivan.name
   end
 
   def test_update_column_for_readonly_attribute
-    minivan = Minivan.find('m1')
+    minivan = Minivan.find("m1")
     prev_color = minivan.color
-    assert_raises(ActiveRecord::ActiveRecordError) { minivan.update_column(:color, 'black') }
+    assert_raises(ActiveRecord::ActiveRecordError) { minivan.update_column(:color, "black") }
     assert_equal prev_color, minivan.color
   end
 
@@ -598,31 +741,31 @@ class PersistenceTest < ActiveRecord::TestCase
   end
 
   def test_update_column_with_one_changed_and_one_updated
-    t = Topic.order('id').limit(1).first
+    t = Topic.order("id").limit(1).first
     author_name = t.author_name
-    t.author_name = 'John'
-    t.update_column(:title, 'super_title')
-    assert_equal 'John', t.author_name
-    assert_equal 'super_title', t.title
+    t.author_name = "John"
+    t.update_column(:title, "super_title")
+    assert_equal "John", t.author_name
+    assert_equal "super_title", t.title
     assert t.changed?, "topic should have changed"
     assert t.author_name_changed?, "author_name should have changed"
 
     t.reload
     assert_equal author_name, t.author_name
-    assert_equal 'super_title', t.title
+    assert_equal "super_title", t.title
   end
 
   def test_update_column_with_default_scope
     developer = DeveloperCalledDavid.first
-    developer.name = 'John'
+    developer.name = "John"
     developer.save!
 
-    assert developer.update_column(:name, 'Will'), 'did not update record due to default scope'
+    assert developer.update_column(:name, "Will"), "did not update record due to default scope"
   end
 
   def test_update_columns
     topic = Topic.find(1)
-    topic.update_columns({ "approved" => true, title: "Sebastian Topic" })
+    topic.update_columns("approved" => true, title: "Sebastian Topic")
     assert topic.approved?
     assert_equal "Sebastian Topic", topic.title
     topic.reload
@@ -643,35 +786,35 @@ class PersistenceTest < ActiveRecord::TestCase
 
   def test_update_columns_should_raise_exception_if_new_record
     topic = Topic.new
-    assert_raises(ActiveRecord::ActiveRecordError) { topic.update_columns({ approved: false }) }
+    assert_raises(ActiveRecord::ActiveRecordError) { topic.update_columns(approved: false) }
   end
 
   def test_update_columns_should_not_leave_the_object_dirty
     topic = Topic.find(1)
-    topic.update({ "content" => "--- Have a nice day\n...\n", :author_name => "Jose" })
+    topic.update("content" => "--- Have a nice day\n...\n", :author_name => "Jose")
 
     topic.reload
-    topic.update_columns({ content: "--- You too\n...\n", "author_name" => "Sebastian" })
+    topic.update_columns(content: "--- You too\n...\n", "author_name" => "Sebastian")
     assert_equal [], topic.changed
 
     topic.reload
-    topic.update_columns({ content: "--- Have a nice day\n...\n", author_name: "Jose" })
+    topic.update_columns(content: "--- Have a nice day\n...\n", author_name: "Jose")
     assert_equal [], topic.changed
   end
 
   def test_update_columns_with_model_having_primary_key_other_than_id
-    minivan = Minivan.find('m1')
-    new_name = 'sebavan'
+    minivan = Minivan.find("m1")
+    new_name = "sebavan"
 
     minivan.update_columns(name: new_name)
     assert_equal new_name, minivan.name
   end
 
   def test_update_columns_with_one_readonly_attribute
-    minivan = Minivan.find('m1')
+    minivan = Minivan.find("m1")
     prev_color = minivan.color
     prev_name = minivan.name
-    assert_raises(ActiveRecord::ActiveRecordError) { minivan.update_columns({ name: "My old minivan", color: 'black' }) }
+    assert_raises(ActiveRecord::ActiveRecordError) { minivan.update_columns(name: "My old minivan", color: "black") }
     assert_equal prev_color, minivan.color
     assert_equal prev_name, minivan.name
 
@@ -697,18 +840,18 @@ class PersistenceTest < ActiveRecord::TestCase
   end
 
   def test_update_columns_with_one_changed_and_one_updated
-    t = Topic.order('id').limit(1).first
+    t = Topic.order("id").limit(1).first
     author_name = t.author_name
-    t.author_name = 'John'
-    t.update_columns(title: 'super_title')
-    assert_equal 'John', t.author_name
-    assert_equal 'super_title', t.title
+    t.author_name = "John"
+    t.update_columns(title: "super_title")
+    assert_equal "John", t.author_name
+    assert_equal "super_title", t.title
     assert t.changed?, "topic should have changed"
     assert t.author_name_changed?, "author_name should have changed"
 
     t.reload
     assert_equal author_name, t.author_name
-    assert_equal 'super_title', t.title
+    assert_equal "super_title", t.title
   end
 
   def test_update_columns_changing_id
@@ -726,10 +869,10 @@ class PersistenceTest < ActiveRecord::TestCase
 
   def test_update_columns_with_default_scope
     developer = DeveloperCalledDavid.first
-    developer.name = 'John'
+    developer.name = "John"
     developer.save!
 
-    assert developer.update_columns(name: 'Will'), 'did not update record due to default scope'
+    assert developer.update_columns(name: "Will"), "did not update record due to default scope"
   end
 
   def test_update
@@ -840,7 +983,7 @@ class PersistenceTest < ActiveRecord::TestCase
   end
 
   def test_persisted_returns_boolean
-    developer = Developer.new(:name => "Jose")
+    developer = Developer.new(name: "Jose")
     assert_equal false, developer.persisted?
     developer.save!
     assert_equal true, developer.persisted?
@@ -860,18 +1003,41 @@ class PersistenceTest < ActiveRecord::TestCase
     should_be_destroyed_reply = Reply.create("title" => "hello", "content" => "world")
     Topic.find(1).replies << should_be_destroyed_reply
 
-    Topic.destroy(1)
+    topic = Topic.destroy(1)
+    assert topic.destroyed?
+
     assert_raise(ActiveRecord::RecordNotFound) { Topic.find(1) }
     assert_raise(ActiveRecord::RecordNotFound) { Reply.find(should_be_destroyed_reply.id) }
   end
 
+  def test_class_level_destroy_is_affected_by_scoping
+    should_not_be_destroyed_reply = Reply.create("title" => "hello", "content" => "world")
+    Topic.find(1).replies << should_not_be_destroyed_reply
+
+    assert_raise(ActiveRecord::RecordNotFound) do
+      Topic.where("1=0").scoping { Topic.destroy(1) }
+    end
+
+    assert_nothing_raised { Topic.find(1) }
+    assert_nothing_raised { Reply.find(should_not_be_destroyed_reply.id) }
+  end
+
   def test_class_level_delete
-    should_be_destroyed_reply = Reply.create("title" => "hello", "content" => "world")
-    Topic.find(1).replies << should_be_destroyed_reply
+    should_not_be_destroyed_reply = Reply.create("title" => "hello", "content" => "world")
+    Topic.find(1).replies << should_not_be_destroyed_reply
 
     Topic.delete(1)
     assert_raise(ActiveRecord::RecordNotFound) { Topic.find(1) }
-    assert_nothing_raised { Reply.find(should_be_destroyed_reply.id) }
+    assert_nothing_raised { Reply.find(should_not_be_destroyed_reply.id) }
+  end
+
+  def test_class_level_delete_is_affected_by_scoping
+    should_not_be_destroyed_reply = Reply.create("title" => "hello", "content" => "world")
+    Topic.find(1).replies << should_not_be_destroyed_reply
+
+    Topic.where("1=0").scoping { Topic.delete(1) }
+    assert_nothing_raised { Topic.find(1) }
+    assert_nothing_raised { Reply.find(should_not_be_destroyed_reply.id) }
   end
 
   def test_create_with_custom_timestamps
@@ -909,7 +1075,7 @@ class PersistenceTest < ActiveRecord::TestCase
   end
 
   def test_reload_removes_custom_selects
-    post = Post.select('posts.*, 1 as wibble').last!
+    post = Post.select("posts.*, 1 as wibble").last!
 
     assert_equal 1, post[:wibble]
     assert_nil post.reload[:wibble]
@@ -930,8 +1096,8 @@ class PersistenceTest < ActiveRecord::TestCase
   def test_reload_via_querycache
     ActiveRecord::Base.connection.enable_query_cache!
     ActiveRecord::Base.connection.clear_query_cache
-    assert ActiveRecord::Base.connection.query_cache_enabled, 'cache should be on'
-    parrot = Parrot.create(:name => 'Shane')
+    assert ActiveRecord::Base.connection.query_cache_enabled, "cache should be on"
+    parrot = Parrot.create(name: "Shane")
 
     # populate the cache with the SELECT result
     found_parrot = Parrot.find(parrot.id)
@@ -940,60 +1106,50 @@ class PersistenceTest < ActiveRecord::TestCase
     # Manually update the 'name' attribute in the DB directly
     assert_equal 1, ActiveRecord::Base.connection.query_cache.length
     ActiveRecord::Base.uncached do
-      found_parrot.name = 'Mary'
+      found_parrot.name = "Mary"
       found_parrot.save
     end
 
     # Now reload, and verify that it gets the DB version, and not the querycache version
     found_parrot.reload
-    assert_equal 'Mary', found_parrot.name
+    assert_equal "Mary", found_parrot.name
 
     found_parrot = Parrot.find(parrot.id)
-    assert_equal 'Mary', found_parrot.name
+    assert_equal "Mary", found_parrot.name
   ensure
     ActiveRecord::Base.connection.disable_query_cache!
   end
 
   class SaveTest < ActiveRecord::TestCase
-    self.use_transactional_tests = false
-
     def test_save_touch_false
-      widget = Class.new(ActiveRecord::Base) do
-        connection.create_table :widgets, force: true do |t|
-          t.string :name
-          t.timestamps null: false
-        end
+      pet = Pet.create!(
+        name: "Bob",
+        created_at: 1.day.ago,
+        updated_at: 1.day.ago)
 
-        self.table_name = :widgets
-      end
+      created_at = pet.created_at
+      updated_at = pet.updated_at
 
-      instance  = widget.create!({
-        name: 'Bob',
-        created_at: 1.day.ago,
-        updated_at: 1.day.ago
-      })
-
-      created_at = instance.created_at
-      updated_at = instance.updated_at
-
-      instance.name = 'Barb'
-      instance.save!(touch: false)
-      assert_equal instance.created_at, created_at
-      assert_equal instance.updated_at, updated_at
-    ensure
-      ActiveRecord::Base.connection.drop_table widget.table_name
-      widget.reset_column_information
+      pet.name = "Barb"
+      pet.save!(touch: false)
+      assert_equal pet.created_at, created_at
+      assert_equal pet.updated_at, updated_at
     end
   end
 
   def test_reset_column_information_resets_children
-    child = Class.new(Topic)
-    child.new # force schema to load
+    child_class = Class.new(Topic)
+    child_class.new # force schema to load
 
     ActiveRecord::Base.connection.add_column(:topics, :foo, :string)
     Topic.reset_column_information
 
-    assert_equal "bar", child.new(foo: :bar).foo
+    # this should redefine attribute methods
+    child_class.new
+
+    assert child_class.instance_methods.include?(:foo)
+    assert child_class.instance_methods.include?(:foo_changed?)
+    assert_equal "bar", child_class.new(foo: :bar).foo
   ensure
     ActiveRecord::Base.connection.remove_column(:topics, :foo)
     Topic.reset_column_information
diff --git a/activerecord/test/cases/pooled_connections_test.rb b/activerecord/test/cases/pooled_connections_test.rb
index bca50dd008..fa7f759e51 100644
--- a/activerecord/test/cases/pooled_connections_test.rb
+++ b/activerecord/test/cases/pooled_connections_test.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require "cases/helper"
 require "models/project"
 require "timeout"
@@ -18,7 +20,7 @@ class PooledConnectionsTest < ActiveRecord::TestCase
 
   # Will deadlock due to lack of Monitor timeouts in 1.9
   def checkout_checkin_connections(pool_size, threads)
-    ActiveRecord::Base.establish_connection(@connection.merge({:pool => pool_size, :checkout_timeout => 0.5}))
+    ActiveRecord::Base.establish_connection(@connection.merge(pool: pool_size, checkout_timeout: 0.5))
     @connection_count = 0
     @timed_out = 0
     threads.times do
@@ -36,7 +38,7 @@ class PooledConnectionsTest < ActiveRecord::TestCase
   end
 
   def checkout_checkin_connections_loop(pool_size, loops)
-    ActiveRecord::Base.establish_connection(@connection.merge({:pool => pool_size, :checkout_timeout => 0.5}))
+    ActiveRecord::Base.establish_connection(@connection.merge(pool: pool_size, checkout_timeout: 0.5))
     @connection_count = 0
     @timed_out = 0
     loops.times do
@@ -66,7 +68,7 @@ class PooledConnectionsTest < ActiveRecord::TestCase
   end
 
   def test_pooled_connection_remove
-    ActiveRecord::Base.establish_connection(@connection.merge({:pool => 2, :checkout_timeout => 0.5}))
+    ActiveRecord::Base.establish_connection(@connection.merge(pool: 2, checkout_timeout: 0.5))
     old_connection = ActiveRecord::Base.connection
     extra_connection = ActiveRecord::Base.connection_pool.checkout
     ActiveRecord::Base.connection_pool.remove(extra_connection)
@@ -75,7 +77,7 @@ class PooledConnectionsTest < ActiveRecord::TestCase
 
   private
 
-  def add_record(name)
-    ActiveRecord::Base.connection_pool.with_connection { Project.create! :name => name }
-  end
+    def add_record(name)
+      ActiveRecord::Base.connection_pool.with_connection { Project.create! name: name }
+    end
 end unless in_memory_db?
diff --git a/activerecord/test/cases/primary_keys_test.rb b/activerecord/test/cases/primary_keys_test.rb
index 52eac4a124..80016fc19d 100644
--- a/activerecord/test/cases/primary_keys_test.rb
+++ b/activerecord/test/cases/primary_keys_test.rb
@@ -1,12 +1,15 @@
+# frozen_string_literal: true
+
 require "cases/helper"
-require 'support/schema_dumping_helper'
-require 'models/topic'
-require 'models/reply'
-require 'models/subscriber'
-require 'models/movie'
-require 'models/keyboard'
-require 'models/mixed_case_monkey'
-require 'models/dashboard'
+require "support/schema_dumping_helper"
+require "models/topic"
+require "models/reply"
+require "models/subscriber"
+require "models/movie"
+require "models/keyboard"
+require "models/mixed_case_monkey"
+require "models/dashboard"
+require "models/non_primary_key"
 
 class PrimaryKeysTest < ActiveRecord::TestCase
   fixtures :topics, :subscribers, :movies, :mixed_case_monkeys
@@ -45,7 +48,7 @@ class PrimaryKeysTest < ActiveRecord::TestCase
     topic = Topic.new
     topic.title = "New Topic"
     assert_nil topic.id
-    assert_nothing_raised { topic.save! }
+    topic.save!
     id = topic.id
 
     topicReloaded = Topic.find(id)
@@ -54,22 +57,35 @@ class PrimaryKeysTest < ActiveRecord::TestCase
 
   def test_customized_primary_key_auto_assigns_on_save
     Keyboard.delete_all
-    keyboard = Keyboard.new(:name => 'HHKB')
-    assert_nothing_raised { keyboard.save! }
-    assert_equal keyboard.id, Keyboard.find_by_name('HHKB').id
+    keyboard = Keyboard.new(name: "HHKB")
+    keyboard.save!
+    assert_equal keyboard.id, Keyboard.find_by_name("HHKB").id
   end
 
   def test_customized_primary_key_can_be_get_before_saving
     keyboard = Keyboard.new
     assert_nil keyboard.id
-    assert_nothing_raised { assert_nil keyboard.key_number }
+    assert_nil keyboard.key_number
   end
 
   def test_customized_string_primary_key_settable_before_save
     subscriber = Subscriber.new
-    assert_nothing_raised { subscriber.id = 'webster123' }
-    assert_equal 'webster123', subscriber.id
-    assert_equal 'webster123', subscriber.nick
+    subscriber.id = "webster123"
+    assert_equal "webster123", subscriber.id
+    assert_equal "webster123", subscriber.nick
+  end
+
+  def test_update_with_non_primary_key_id_column
+    subscriber = Subscriber.first
+    subscriber.update(update_count: 1)
+    subscriber.reload
+    assert_equal 1, subscriber.update_count
+  end
+
+  def test_update_columns_with_non_primary_key_id_column
+    subscriber = Subscriber.first
+    subscriber.update_columns(id: 1)
+    assert_not_equal 1, subscriber.nick
   end
 
   def test_string_key
@@ -82,13 +98,19 @@ class PrimaryKeysTest < ActiveRecord::TestCase
     subscriber.id = "jdoe"
     assert_equal("jdoe", subscriber.id)
     subscriber.name = "John Doe"
-    assert_nothing_raised { subscriber.save! }
+    subscriber.save!
     assert_equal("jdoe", subscriber.id)
 
     subscriberReloaded = Subscriber.find("jdoe")
     assert_equal("John Doe", subscriberReloaded.name)
   end
 
+  def test_id_column_that_is_not_primary_key
+    NonPrimaryKey.create!(id: 100)
+    actual = NonPrimaryKey.find_by(id: 100)
+    assert_match %r{<NonPrimaryKey id: 100}, actual.inspect
+  end
+
   def test_find_with_more_than_one_string_key
     assert_equal 2, Subscriber.find(subscribers(:first).nick, subscribers(:second).nick).length
   end
@@ -113,48 +135,45 @@ class PrimaryKeysTest < ActiveRecord::TestCase
   def test_delete_should_quote_pkey
     assert_nothing_raised { MixedCaseMonkey.delete(1) }
   end
+
   def test_update_counters_should_quote_pkey_and_quote_counter_columns
-    assert_nothing_raised { MixedCaseMonkey.update_counters(1, :fleaCount => 99) }
+    assert_nothing_raised { MixedCaseMonkey.update_counters(1, fleaCount: 99) }
   end
+
   def test_find_with_one_id_should_quote_pkey
     assert_nothing_raised { MixedCaseMonkey.find(1) }
   end
+
   def test_find_with_multiple_ids_should_quote_pkey
-    assert_nothing_raised { MixedCaseMonkey.find([1,2]) }
+    assert_nothing_raised { MixedCaseMonkey.find([1, 2]) }
   end
+
   def test_instance_update_should_quote_pkey
     assert_nothing_raised { MixedCaseMonkey.find(1).save }
   end
+
   def test_instance_destroy_should_quote_pkey
     assert_nothing_raised { MixedCaseMonkey.find(1).destroy }
   end
 
-  def test_supports_primary_key
-    assert_nothing_raised do
-      ActiveRecord::Base.connection.supports_primary_key?
+  def test_primary_key_returns_value_if_it_exists
+    klass = Class.new(ActiveRecord::Base) do
+      self.table_name = "developers"
     end
-  end
 
-  if ActiveRecord::Base.connection.supports_primary_key?
-    def test_primary_key_returns_value_if_it_exists
-      klass = Class.new(ActiveRecord::Base) do
-        self.table_name = 'developers'
-      end
+    assert_equal "id", klass.primary_key
+  end
 
-      assert_equal 'id', klass.primary_key
+  def test_primary_key_returns_nil_if_it_does_not_exist
+    klass = Class.new(ActiveRecord::Base) do
+      self.table_name = "developers_projects"
     end
 
-    def test_primary_key_returns_nil_if_it_does_not_exist
-      klass = Class.new(ActiveRecord::Base) do
-        self.table_name = 'developers_projects'
-      end
-
-      assert_nil klass.primary_key
-    end
+    assert_nil klass.primary_key
   end
 
   def test_quoted_primary_key_after_set_primary_key
-    k = Class.new( ActiveRecord::Base )
+    k = Class.new(ActiveRecord::Base)
     assert_equal k.connection.quote_column_name("id"), k.quoted_primary_key
     k.primary_key = "foo"
     assert_equal k.connection.quote_column_name("foo"), k.quoted_primary_key
@@ -166,12 +185,22 @@ class PrimaryKeysTest < ActiveRecord::TestCase
   end
 
   def test_primary_key_update_with_custom_key_name
-    dashboard = Dashboard.create!(dashboard_id: '1')
-    dashboard.id = '2'
+    dashboard = Dashboard.create!(dashboard_id: "1")
+    dashboard.id = "2"
     dashboard.save!
 
     dashboard = Dashboard.first
-    assert_equal '2', dashboard.id
+    assert_equal "2", dashboard.id
+  end
+
+  def test_create_without_primary_key_no_extra_query
+    skip if current_adapter?(:OracleAdapter)
+
+    klass = Class.new(ActiveRecord::Base) do
+      self.table_name = "dashboards"
+    end
+    klass.create! # warmup schema cache
+    assert_queries(3, ignore_none: true) { klass.create! }
   end
 
   if current_adapter?(:PostgreSQLAdapter)
@@ -197,17 +226,54 @@ class PrimaryKeyWithNoConnectionTest < ActiveRecord::TestCase
       connection = ActiveRecord::Base.remove_connection
 
       model = Class.new(ActiveRecord::Base)
-      model.primary_key = 'foo'
+      model.primary_key = "foo"
 
-      assert_equal 'foo', model.primary_key
+      assert_equal "foo", model.primary_key
 
       ActiveRecord::Base.establish_connection(connection)
 
-      assert_equal 'foo', model.primary_key
+      assert_equal "foo", model.primary_key
     end
   end
 end
 
+class PrimaryKeyWithAutoIncrementTest < ActiveRecord::TestCase
+  self.use_transactional_tests = false
+
+  class AutoIncrement < ActiveRecord::Base
+  end
+
+  def setup
+    @connection = ActiveRecord::Base.connection
+  end
+
+  def teardown
+    @connection.drop_table(:auto_increments, if_exists: true)
+  end
+
+  def test_primary_key_with_integer
+    @connection.create_table(:auto_increments, id: :integer, force: true)
+    assert_auto_incremented
+  end
+
+  def test_primary_key_with_bigint
+    @connection.create_table(:auto_increments, id: :bigint, force: true)
+    assert_auto_incremented
+  end
+
+  private
+    def assert_auto_incremented
+      record1 = AutoIncrement.create!
+      assert_not_nil record1.id
+
+      record1.destroy
+
+      record2 = AutoIncrement.create!
+      assert_not_nil record2.id
+      assert_operator record2.id, :>, record1.id
+    end
+end
+
 class PrimaryKeyAnyTypeTest < ActiveRecord::TestCase
   include SchemaDumpingHelper
 
@@ -232,12 +298,22 @@ class PrimaryKeyAnyTypeTest < ActiveRecord::TestCase
     assert_not column.null
     assert_equal :string, column.type
     assert_equal 42, column.limit
+  ensure
+    Barcode.reset_column_information
   end
 
   test "schema dump primary key includes type and options" do
     schema = dump_table_schema "barcodes"
     assert_match %r{create_table "barcodes", primary_key: "code", id: :string, limit: 42}, schema
   end
+
+  if current_adapter?(:Mysql2Adapter) && subsecond_precision_supported?
+    test "schema typed primary key column" do
+      @connection.create_table(:scheduled_logs, id: :timestamp, precision: 6, force: true)
+      schema = dump_table_schema("scheduled_logs")
+      assert_match %r/create_table "scheduled_logs", id: :timestamp, precision: 6/, schema
+    end
+  end
 end
 
 class CompositePrimaryKeyTest < ActiveRecord::TestCase
@@ -247,75 +323,93 @@ class CompositePrimaryKeyTest < ActiveRecord::TestCase
 
   def setup
     @connection = ActiveRecord::Base.connection
-    @connection.create_table(:barcodes, primary_key: ["region", "code"], force: true) do |t|
+    @connection.schema_cache.clear!
+    @connection.create_table(:uber_barcodes, primary_key: ["region", "code"], force: true) do |t|
+      t.string :region
+      t.integer :code
+    end
+    @connection.create_table(:barcodes_reverse, primary_key: ["code", "region"], force: true) do |t|
       t.string :region
       t.integer :code
     end
+    @connection.create_table(:travels, primary_key: ["from", "to"], force: true) do |t|
+      t.string :from
+      t.string :to
+    end
   end
 
   def teardown
-    @connection.drop_table(:barcodes, if_exists: true)
+    @connection.drop_table :uber_barcodes, if_exists: true
+    @connection.drop_table :barcodes_reverse, if_exists: true
+    @connection.drop_table :travels, if_exists: true
   end
 
   def test_composite_primary_key
-    assert_equal ["region", "code"], @connection.primary_keys("barcodes")
+    assert_equal ["region", "code"], @connection.primary_keys("uber_barcodes")
+  end
+
+  def test_composite_primary_key_with_reserved_words
+    assert_equal ["from", "to"], @connection.primary_keys("travels")
+  end
+
+  def test_composite_primary_key_out_of_order
+    skip if current_adapter?(:SQLite3Adapter)
+    assert_equal ["code", "region"], @connection.primary_keys("barcodes_reverse")
   end
 
   def test_primary_key_issues_warning
+    model = Class.new(ActiveRecord::Base) do
+      def self.table_name
+        "uber_barcodes"
+      end
+    end
     warning = capture(:stderr) do
-      assert_nil @connection.primary_key("barcodes")
+      assert_nil model.primary_key
     end
-    assert_match(/WARNING: Rails does not support composite primary key\./, warning)
+    assert_match(/WARNING: Active Record does not support composite primary key\./, warning)
   end
 
   def test_collectly_dump_composite_primary_key
-    schema = dump_table_schema "barcodes"
-    assert_match %r{create_table "barcodes", primary_key: \["region", "code"\]}, schema
+    schema = dump_table_schema "uber_barcodes"
+    assert_match %r{create_table "uber_barcodes", primary_key: \["region", "code"\]}, schema
   end
-end
-
-if current_adapter?(:Mysql2Adapter)
-  class PrimaryKeyWithAnsiQuotesTest < ActiveRecord::TestCase
-    self.use_transactional_tests = false
 
-    def test_primary_key_method_with_ansi_quotes
-      con = ActiveRecord::Base.connection
-      con.execute("SET SESSION sql_mode='ANSI_QUOTES'")
-      assert_equal "id", con.primary_key("topics")
-    ensure
-      con.reconnect!
-    end
+  def test_dumping_composite_primary_key_out_of_order
+    skip if current_adapter?(:SQLite3Adapter)
+    schema = dump_table_schema "barcodes_reverse"
+    assert_match %r{create_table "barcodes_reverse", primary_key: \["code", "region"\]}, schema
   end
+end
 
-  class PrimaryKeyBigintNilDefaultTest < ActiveRecord::TestCase
-    include SchemaDumpingHelper
+class PrimaryKeyIntegerNilDefaultTest < ActiveRecord::TestCase
+  include SchemaDumpingHelper
 
-    self.use_transactional_tests = false
+  self.use_transactional_tests = false
 
-    def setup
-      @connection = ActiveRecord::Base.connection
-      @connection.create_table(:bigint_defaults, id: :bigint, default: nil, force: true)
-    end
+  def setup
+    @connection = ActiveRecord::Base.connection
+  end
 
-    def teardown
-      @connection.drop_table :bigint_defaults, if_exists: true
-    end
+  def teardown
+    @connection.drop_table :int_defaults, if_exists: true
+  end
 
-    test "primary key with bigint allows default override via nil" do
-      column = @connection.columns(:bigint_defaults).find { |c| c.name == 'id' }
-      assert column.bigint?
-      assert_not column.auto_increment?
-    end
+  def test_schema_dump_primary_key_integer_with_default_nil
+    skip if current_adapter?(:SQLite3Adapter)
+    @connection.create_table(:int_defaults, id: :integer, default: nil, force: true)
+    schema = dump_table_schema "int_defaults"
+    assert_match %r{create_table "int_defaults", id: :integer, default: nil}, schema
+  end
 
-    test "schema dump primary key with bigint default nil" do
-      schema = dump_table_schema "bigint_defaults"
-      assert_match %r{create_table "bigint_defaults", id: :bigint, default: nil}, schema
-    end
+  def test_schema_dump_primary_key_bigint_with_default_nil
+    @connection.create_table(:int_defaults, id: :bigint, default: nil, force: true)
+    schema = dump_table_schema "int_defaults"
+    assert_match %r{create_table "int_defaults", id: :bigint, default: nil}, schema
   end
 end
 
 if current_adapter?(:PostgreSQLAdapter, :Mysql2Adapter)
-  class PrimaryKeyBigSerialTest < ActiveRecord::TestCase
+  class PrimaryKeyIntegerTest < ActiveRecord::TestCase
     include SchemaDumpingHelper
 
     self.use_transactional_tests = false
@@ -325,46 +419,55 @@ if current_adapter?(:PostgreSQLAdapter, :Mysql2Adapter)
 
     setup do
       @connection = ActiveRecord::Base.connection
-      if current_adapter?(:PostgreSQLAdapter)
-        @connection.create_table(:widgets, id: :bigserial, force: true)
-      else
-        @connection.create_table(:widgets, id: :bigint, force: true)
-      end
+      @pk_type = current_adapter?(:PostgreSQLAdapter) ? :serial : :integer
     end
 
     teardown do
       @connection.drop_table :widgets, if_exists: true
-      Widget.reset_column_information
     end
 
-    test "primary key column type with bigserial" do
-      column_type = Widget.type_for_attribute(Widget.primary_key)
-      assert_equal :integer, column_type.type
-      assert_equal 8, column_type.limit
+    test "primary key column type with serial/integer" do
+      @connection.create_table(:widgets, id: @pk_type, force: true)
+      column = @connection.columns(:widgets).find { |c| c.name == "id" }
+      assert_equal :integer, column.type
+      assert_not column.bigint?
     end
 
-    test "primary key with bigserial are automatically numbered" do
+    test "primary key with serial/integer are automatically numbered" do
+      @connection.create_table(:widgets, id: @pk_type, force: true)
       widget = Widget.create!
       assert_not_nil widget.id
     end
 
-    test "schema dump primary key with bigserial" do
+    test "schema dump primary key with serial/integer" do
+      @connection.create_table(:widgets, id: @pk_type, force: true)
       schema = dump_table_schema "widgets"
-      if current_adapter?(:PostgreSQLAdapter)
-        assert_match %r{create_table "widgets", id: :bigserial, force: :cascade}, schema
-      else
-        assert_match %r{create_table "widgets", id: :bigint, force: :cascade}, schema
-      end
+      assert_match %r{create_table "widgets", id: :#{@pk_type}, }, schema
     end
 
     if current_adapter?(:Mysql2Adapter)
       test "primary key column type with options" do
-        @connection.create_table(:widgets, id: :primary_key, limit: 8, unsigned: true, force: true)
-        column = @connection.columns(:widgets).find { |c| c.name == 'id' }
+        @connection.create_table(:widgets, id: :primary_key, limit: 4, unsigned: true, force: true)
+        column = @connection.columns(:widgets).find { |c| c.name == "id" }
+        assert column.auto_increment?
+        assert_equal :integer, column.type
+        assert_not column.bigint?
+        assert column.unsigned?
+
+        schema = dump_table_schema "widgets"
+        assert_match %r{create_table "widgets", id: :integer, unsigned: true, }, schema
+      end
+
+      test "bigint primary key with unsigned" do
+        @connection.create_table(:widgets, id: :bigint, unsigned: true, force: true)
+        column = @connection.columns(:widgets).find { |c| c.name == "id" }
         assert column.auto_increment?
         assert_equal :integer, column.type
-        assert_equal 8, column.limit
+        assert column.bigint?
         assert column.unsigned?
+
+        schema = dump_table_schema "widgets"
+        assert_match %r{create_table "widgets", id: :bigint, unsigned: true, }, schema
       end
     end
   end
diff --git a/activerecord/test/cases/query_cache_test.rb b/activerecord/test/cases/query_cache_test.rb
index d5c01315c1..ad05f70933 100644
--- a/activerecord/test/cases/query_cache_test.rb
+++ b/activerecord/test/cases/query_cache_test.rb
@@ -1,54 +1,141 @@
+# frozen_string_literal: true
+
 require "cases/helper"
-require 'models/topic'
-require 'models/task'
-require 'models/category'
-require 'models/post'
-require 'rack'
+require "models/topic"
+require "models/task"
+require "models/category"
+require "models/post"
+require "rack"
 
 class QueryCacheTest < ActiveRecord::TestCase
+  self.use_transactional_tests = false
+
   fixtures :tasks, :topics, :categories, :posts, :categories_posts
 
-  teardown do
+  class ShouldNotHaveExceptionsLogger < ActiveRecord::LogSubscriber
+    attr_reader :logger
+
+    def initialize
+      super
+      @logger = ::Logger.new File::NULL
+      @exception = false
+    end
+
+    def exception?
+      @exception
+    end
+
+    def sql(event)
+      super
+    rescue
+      @exception = true
+    end
+  end
+
+  def teardown
     Task.connection.clear_query_cache
     ActiveRecord::Base.connection.disable_query_cache!
+    super
   end
 
   def test_exceptional_middleware_clears_and_disables_cache_on_error
-    assert !ActiveRecord::Base.connection.query_cache_enabled, 'cache off'
+    assert_cache :off
 
     mw = middleware { |env|
       Task.find 1
       Task.find 1
-      assert_equal 1, ActiveRecord::Base.connection.query_cache.length
+      query_cache = ActiveRecord::Base.connection.query_cache
+      assert_equal 1, query_cache.length, query_cache.keys
       raise "lol borked"
     }
     assert_raises(RuntimeError) { mw.call({}) }
 
-    assert_equal 0, ActiveRecord::Base.connection.query_cache.length
-    assert !ActiveRecord::Base.connection.query_cache_enabled, 'cache off'
+    assert_cache :off
   end
 
-  def test_exceptional_middleware_leaves_enabled_cache_alone
-    ActiveRecord::Base.connection.enable_query_cache!
+  private def with_temporary_connection_pool
+    old_pool = ActiveRecord::Base.connection_handler.retrieve_connection_pool(ActiveRecord::Base.connection_specification_name)
+    new_pool = ActiveRecord::ConnectionAdapters::ConnectionPool.new ActiveRecord::Base.connection_pool.spec
+    ActiveRecord::Base.connection_handler.send(:owner_to_pool)["primary"] = new_pool
 
-    mw = middleware { |env|
-      raise "lol borked"
-    }
-    assert_raises(RuntimeError) { mw.call({}) }
-
-    assert ActiveRecord::Base.connection.query_cache_enabled, 'cache on'
+    yield
+  ensure
+    ActiveRecord::Base.connection_handler.send(:owner_to_pool)["primary"] = old_pool
   end
 
-  def test_exceptional_middleware_assigns_original_connection_id_on_error
-    connection_id = ActiveRecord::Base.connection_id
+  def test_query_cache_across_threads
+    with_temporary_connection_pool do
+      begin
+        if in_memory_db?
+          # Separate connections to an in-memory database create an entirely new database,
+          # with an empty schema etc, so we just stub out this schema on the fly.
+          ActiveRecord::Base.connection_pool.with_connection do |connection|
+            connection.create_table :tasks do |t|
+              t.datetime :starting
+              t.datetime :ending
+            end
+          end
+          ActiveRecord::FixtureSet.create_fixtures(self.class.fixture_path, ["tasks"], {}, ActiveRecord::Base)
+        end
 
-    mw = middleware { |env|
-      ActiveRecord::Base.connection_id = self.object_id
-      raise "lol borked"
-    }
-    assert_raises(RuntimeError) { mw.call({}) }
+        ActiveRecord::Base.connection_pool.connections.each do |conn|
+          assert_cache :off, conn
+        end
+
+        assert !ActiveRecord::Base.connection.nil?
+        assert_cache :off
+
+        middleware {
+          assert_cache :clean
+
+          Task.find 1
+          assert_cache :dirty
+
+          thread_1_connection = ActiveRecord::Base.connection
+          ActiveRecord::Base.clear_active_connections!
+          assert_cache :off, thread_1_connection
+
+          started = Concurrent::Event.new
+          checked = Concurrent::Event.new
+
+          thread_2_connection = nil
+          thread = Thread.new {
+            thread_2_connection = ActiveRecord::Base.connection
+
+            assert_equal thread_2_connection, thread_1_connection
+            assert_cache :off
+
+            middleware {
+              assert_cache :clean
+
+              Task.find 1
+              assert_cache :dirty
+
+              started.set
+              checked.wait
+
+              ActiveRecord::Base.clear_active_connections!
+            }.call({})
+          }
+
+          started.wait
 
-    assert_equal connection_id, ActiveRecord::Base.connection_id
+          thread_1_connection = ActiveRecord::Base.connection
+          assert_not_equal thread_1_connection, thread_2_connection
+          assert_cache :dirty, thread_2_connection
+          checked.set
+          thread.join
+
+          assert_cache :off, thread_2_connection
+        }.call({})
+
+        ActiveRecord::Base.connection_pool.connections.each do |conn|
+          assert_cache :off, conn
+        end
+      ensure
+        ActiveRecord::Base.connection_pool.disconnect!
+      end
+    end
   end
 
   def test_middleware_delegates
@@ -58,24 +145,25 @@ class QueryCacheTest < ActiveRecord::TestCase
       [200, {}, nil]
     }
     mw.call({})
-    assert called, 'middleware should delegate'
+    assert called, "middleware should delegate"
   end
 
   def test_middleware_caches
     mw = middleware { |env|
       Task.find 1
       Task.find 1
-      assert_equal 1, ActiveRecord::Base.connection.query_cache.length
+      query_cache = ActiveRecord::Base.connection.query_cache
+      assert_equal 1, query_cache.length, query_cache.keys
       [200, {}, nil]
     }
     mw.call({})
   end
 
   def test_cache_enabled_during_call
-    assert !ActiveRecord::Base.connection.query_cache_enabled, 'cache off'
+    assert_cache :off
 
     mw = middleware { |env|
-      assert ActiveRecord::Base.connection.query_cache_enabled, 'cache on'
+      assert_cache :clean
       [200, {}, nil]
     }
     mw.call({})
@@ -120,6 +208,52 @@ class QueryCacheTest < ActiveRecord::TestCase
     end
   end
 
+  def test_exists_queries_with_cache
+    Post.cache do
+      assert_queries(1) { Post.exists?; Post.exists? }
+    end
+  end
+
+  def test_select_all_with_cache
+    Post.cache do
+      assert_queries(1) do
+        2.times { Post.connection.select_all(Post.all) }
+      end
+    end
+  end
+
+  def test_select_one_with_cache
+    Post.cache do
+      assert_queries(1) do
+        2.times { Post.connection.select_one(Post.all) }
+      end
+    end
+  end
+
+  def test_select_value_with_cache
+    Post.cache do
+      assert_queries(1) do
+        2.times { Post.connection.select_value(Post.all) }
+      end
+    end
+  end
+
+  def test_select_values_with_cache
+    Post.cache do
+      assert_queries(1) do
+        2.times { Post.connection.select_values(Post.all) }
+      end
+    end
+  end
+
+  def test_select_rows_with_cache
+    Post.cache do
+      assert_queries(1) do
+        2.times { Post.connection.select_rows(Post.all) }
+      end
+    end
+  end
+
   def test_query_cache_dups_results_correctly
     Task.cache do
       now  = Time.now.utc
@@ -131,6 +265,33 @@ class QueryCacheTest < ActiveRecord::TestCase
     end
   end
 
+  def test_cache_does_not_raise_exceptions
+    logger = ShouldNotHaveExceptionsLogger.new
+    subscriber = ActiveSupport::Notifications.subscribe "sql.active_record", logger
+
+    ActiveRecord::Base.cache do
+      assert_queries(1) { Task.find(1); Task.find(1) }
+    end
+
+    assert_not_predicate logger, :exception?
+  ensure
+    ActiveSupport::Notifications.unsubscribe subscriber
+  end
+
+  def test_query_cache_does_not_allow_sql_key_mutation
+    subscriber = ActiveSupport::Notifications.subscribe("sql.active_record") do |_, _, _, _, payload|
+      payload[:sql].downcase!
+    end
+
+    assert_raises frozen_error_class do
+      ActiveRecord::Base.cache do
+        assert_queries(1) { Task.find(1); Task.find(1) }
+      end
+    end
+  ensure
+    ActiveSupport::Notifications.unsubscribe subscriber
+  end
+
   def test_cache_is_flat
     Task.cache do
       assert_queries(1) { Topic.find(1); Topic.find(1); }
@@ -141,14 +302,10 @@ class QueryCacheTest < ActiveRecord::TestCase
     end
   end
 
-  def test_cache_does_not_wrap_string_results_in_arrays
+  def test_cache_does_not_wrap_results_in_arrays
     Task.cache do
-      # Oracle adapter returns count() as Integer or Float
-      if current_adapter?(:OracleAdapter)
-        assert_kind_of Numeric, Task.connection.select_value("SELECT count(*) AS count_all FROM tasks")
-      elsif current_adapter?(:SQLite3Adapter, :Mysql2Adapter, :PostgreSQLAdapter)
-        # Future versions of the sqlite3 adapter will return numeric
-        assert_instance_of Fixnum, Task.connection.select_value("SELECT count(*) AS count_all FROM tasks")
+      if current_adapter?(:SQLite3Adapter, :Mysql2Adapter, :PostgreSQLAdapter, :OracleAdapter)
+        assert_equal 2, Task.connection.select_value("SELECT count(*) AS count_all FROM tasks")
       else
         assert_instance_of String, Task.connection.select_value("SELECT count(*) AS count_all FROM tasks")
       end
@@ -163,31 +320,45 @@ class QueryCacheTest < ActiveRecord::TestCase
     end
   end
 
-  def test_cache_is_available_when_connection_is_connected
-    conf = ActiveRecord::Base.configurations
+  def test_cache_is_available_when_using_a_not_connected_connection
+    skip "In-Memory DB can't test for using a not connected connection" if in_memory_db?
+    with_temporary_connection_pool do
+      spec_name = Task.connection_specification_name
+      conf = ActiveRecord::Base.configurations["arunit"].merge("name" => "test2")
+      ActiveRecord::Base.connection_handler.establish_connection(conf)
+      Task.connection_specification_name = "test2"
+      refute Task.connected?
 
-    ActiveRecord::Base.configurations = {}
-    Task.cache do
-      assert_queries(1) { Task.find(1); Task.find(1) }
+      Task.cache do
+        begin
+          assert_queries(1) { Task.find(1); Task.find(1) }
+        ensure
+          ActiveRecord::Base.connection_handler.remove_connection(Task.connection_specification_name)
+          Task.connection_specification_name = spec_name
+        end
+      end
     end
-  ensure
-    ActiveRecord::Base.configurations = conf
   end
 
-  def test_cache_is_not_available_when_using_a_not_connected_connection
-    spec_name = Task.connection_specification_name
-    conf = ActiveRecord::Base.configurations['arunit'].merge('name' => 'test2')
-    ActiveRecord::Base.connection_handler.establish_connection(conf)
-    Task.connection_specification_name = "test2"
-    refute Task.connected?
+  def test_query_cache_executes_new_queries_within_block
+    ActiveRecord::Base.connection.enable_query_cache!
 
-    Task.cache do
-      Task.connection # warmup postgresql connection setup queries
-      assert_queries(2) { Task.find(1); Task.find(1) }
+    # Warm up the cache by running the query
+    assert_queries(1) do
+      assert_equal 0, Post.where(title: "test").to_a.count
+    end
+
+    # Check that if the same query is run again, no queries are executed
+    assert_queries(0) do
+      assert_equal 0, Post.where(title: "test").to_a.count
+    end
+
+    ActiveRecord::Base.connection.uncached do
+      # Check that new query is executed, avoiding the cache
+      assert_queries(1) do
+        assert_equal 0, Post.where(title: "test").to_a.count
+      end
     end
-  ensure
-    ActiveRecord::Base.connection_handler.remove_connection(Task.connection_specification_name)
-    Task.connection_specification_name = spec_name
   end
 
   def test_query_cache_doesnt_leak_cached_results_of_rolled_back_queries
@@ -195,44 +366,132 @@ class QueryCacheTest < ActiveRecord::TestCase
     post = Post.first
 
     Post.transaction do
-      post.update_attributes(title: 'rollback')
-      assert_equal 1, Post.where(title: 'rollback').to_a.count
+      post.update_attributes(title: "rollback")
+      assert_equal 1, Post.where(title: "rollback").to_a.count
       raise ActiveRecord::Rollback
     end
 
-    assert_equal 0, Post.where(title: 'rollback').to_a.count
+    assert_equal 0, Post.where(title: "rollback").to_a.count
 
     ActiveRecord::Base.connection.uncached do
-      assert_equal 0, Post.where(title: 'rollback').to_a.count
+      assert_equal 0, Post.where(title: "rollback").to_a.count
     end
 
     begin
       Post.transaction do
-        post.update_attributes(title: 'rollback')
-        assert_equal 1, Post.where(title: 'rollback').to_a.count
-        raise 'broken'
+        post.update_attributes(title: "rollback")
+        assert_equal 1, Post.where(title: "rollback").to_a.count
+        raise "broken"
       end
     rescue Exception
     end
 
-    assert_equal 0, Post.where(title: 'rollback').to_a.count
+    assert_equal 0, Post.where(title: "rollback").to_a.count
 
     ActiveRecord::Base.connection.uncached do
-      assert_equal 0, Post.where(title: 'rollback').to_a.count
+      assert_equal 0, Post.where(title: "rollback").to_a.count
+    end
+  end
+
+  def test_query_cached_even_when_types_are_reset
+    Task.cache do
+      # Warm the cache
+      Task.find(1)
+
+      # Preload the type cache again (so we don't have those queries issued during our assertions)
+      Task.connection.send(:reload_type_map)
+
+      # Clear places where type information is cached
+      Task.reset_column_information
+      Task.initialize_find_by_cache
+
+      assert_queries(0) do
+        Task.find(1)
+      end
+    end
+  end
+
+  def test_query_cache_does_not_establish_connection_if_unconnected
+    with_temporary_connection_pool do
+      ActiveRecord::Base.clear_active_connections!
+      refute ActiveRecord::Base.connection_handler.active_connections? # sanity check
+
+      middleware {
+        refute ActiveRecord::Base.connection_handler.active_connections?, "QueryCache forced ActiveRecord::Base to establish a connection in setup"
+      }.call({})
+
+      refute ActiveRecord::Base.connection_handler.active_connections?, "QueryCache forced ActiveRecord::Base to establish a connection in cleanup"
     end
   end
 
+  def test_query_cache_is_enabled_on_connections_established_after_middleware_runs
+    with_temporary_connection_pool do
+      ActiveRecord::Base.clear_active_connections!
+      refute ActiveRecord::Base.connection_handler.active_connections? # sanity check
+
+      middleware {
+        assert ActiveRecord::Base.connection.query_cache_enabled, "QueryCache did not get lazily enabled"
+      }.call({})
+    end
+  end
+
+  def test_query_caching_is_local_to_the_current_thread
+    with_temporary_connection_pool do
+      ActiveRecord::Base.clear_active_connections!
+
+      middleware {
+        assert ActiveRecord::Base.connection_pool.query_cache_enabled
+        assert ActiveRecord::Base.connection.query_cache_enabled
+
+        Thread.new {
+          refute ActiveRecord::Base.connection_pool.query_cache_enabled
+          refute ActiveRecord::Base.connection.query_cache_enabled
+        }.join
+      }.call({})
+
+    end
+  end
+
+  def test_query_cache_is_enabled_on_all_connection_pools
+    middleware {
+      ActiveRecord::Base.connection_handler.connection_pool_list.each do |pool|
+        assert pool.query_cache_enabled
+        assert pool.connection.query_cache_enabled
+      end
+    }.call({})
+  end
+
   private
     def middleware(&app)
       executor = Class.new(ActiveSupport::Executor)
       ActiveRecord::QueryCache.install_executor_hooks executor
       lambda { |env| executor.wrap { app.call(env) } }
     end
+
+    def assert_cache(state, connection = ActiveRecord::Base.connection)
+      case state
+      when :off
+        assert !connection.query_cache_enabled, "cache should be off"
+        assert connection.query_cache.empty?, "cache should be empty"
+      when :clean
+        assert connection.query_cache_enabled, "cache should be on"
+        assert connection.query_cache.empty?, "cache should be empty"
+      when :dirty
+        assert connection.query_cache_enabled, "cache should be on"
+        assert !connection.query_cache.empty?, "cache should be dirty"
+      else
+        raise "unknown state"
+      end
+    end
 end
 
 class QueryCacheExpiryTest < ActiveRecord::TestCase
   fixtures :tasks, :posts, :categories, :categories_posts
 
+  def teardown
+    Task.connection.clear_query_cache
+  end
+
   def test_cache_gets_cleared_after_migration
     # warm the cache
     Post.find(1)
@@ -308,4 +567,16 @@ class QueryCacheExpiryTest < ActiveRecord::TestCase
       end
     end
   end
+
+  test "threads use the same connection" do
+    @connection_1 = ActiveRecord::Base.connection.object_id
+
+    thread_a = Thread.new do
+      @connection_2 = ActiveRecord::Base.connection.object_id
+    end
+
+    thread_a.join
+
+    assert_equal @connection_1, @connection_2
+  end
 end
diff --git a/activerecord/test/cases/quoting_test.rb b/activerecord/test/cases/quoting_test.rb
index c01c82f4f5..6534770c57 100644
--- a/activerecord/test/cases/quoting_test.rb
+++ b/activerecord/test/cases/quoting_test.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require "cases/helper"
 
 module ActiveRecord
@@ -8,28 +10,28 @@ module ActiveRecord
       end
 
       def test_quoted_true
-        assert_equal "'t'", @quoter.quoted_true
+        assert_equal "TRUE", @quoter.quoted_true
       end
 
       def test_quoted_false
-        assert_equal "'f'", @quoter.quoted_false
+        assert_equal "FALSE", @quoter.quoted_false
       end
 
       def test_quote_column_name
-        assert_equal "foo", @quoter.quote_column_name('foo')
+        assert_equal "foo", @quoter.quote_column_name("foo")
       end
 
       def test_quote_table_name
-        assert_equal "foo", @quoter.quote_table_name('foo')
+        assert_equal "foo", @quoter.quote_table_name("foo")
       end
 
       def test_quote_table_name_calls_quote_column_name
         @quoter.extend(Module.new {
           def quote_column_name(string)
-            'lol'
+            "lol"
           end
         })
-        assert_equal 'lol', @quoter.quote_table_name('foo')
+        assert_equal "lol", @quoter.quote_table_name("foo")
       end
 
       def test_quote_string
@@ -81,73 +83,156 @@ module ActiveRecord
         end
       end
 
-      def test_quote_with_quoted_id
-        assert_equal 1, @quoter.quote(Struct.new(:quoted_id).new(1), nil)
-      end
-
       def test_quote_nil
-        assert_equal 'NULL', @quoter.quote(nil, nil)
+        assert_equal "NULL", @quoter.quote(nil)
       end
 
       def test_quote_true
-        assert_equal @quoter.quoted_true, @quoter.quote(true, nil)
+        assert_equal @quoter.quoted_true, @quoter.quote(true)
       end
 
       def test_quote_false
-        assert_equal @quoter.quoted_false, @quoter.quote(false, nil)
+        assert_equal @quoter.quoted_false, @quoter.quote(false)
       end
 
       def test_quote_float
         float = 1.2
-        assert_equal float.to_s, @quoter.quote(float, nil)
+        assert_equal float.to_s, @quoter.quote(float)
       end
 
       def test_quote_integer
         integer = 1
-        assert_equal integer.to_s, @quoter.quote(integer, nil)
+        assert_equal integer.to_s, @quoter.quote(integer)
       end
 
       def test_quote_bignum
         bignum = 1 << 100
-        assert_equal bignum.to_s, @quoter.quote(bignum, nil)
+        assert_equal bignum.to_s, @quoter.quote(bignum)
       end
 
       def test_quote_bigdecimal
-        bigdec = BigDecimal.new((1 << 100).to_s)
-        assert_equal bigdec.to_s('F'), @quoter.quote(bigdec, nil)
+        bigdec = BigDecimal((1 << 100).to_s)
+        assert_equal bigdec.to_s("F"), @quoter.quote(bigdec)
       end
 
       def test_dates_and_times
-        @quoter.extend(Module.new { def quoted_date(value) 'lol' end })
-        assert_equal "'lol'", @quoter.quote(Date.today, nil)
-        assert_equal "'lol'", @quoter.quote(Time.now, nil)
-        assert_equal "'lol'", @quoter.quote(DateTime.now, nil)
+        @quoter.extend(Module.new { def quoted_date(value) "lol" end })
+        assert_equal "'lol'", @quoter.quote(Date.today)
+        assert_equal "'lol'", @quoter.quote(Time.now)
+        assert_equal "'lol'", @quoter.quote(DateTime.now)
+      end
+
+      def test_quoting_classes
+        assert_equal "'Object'", @quoter.quote(Object)
       end
 
       def test_crazy_object
         crazy = Object.new
         e = assert_raises(TypeError) do
-          @quoter.quote(crazy, nil)
+          @quoter.quote(crazy)
         end
         assert_equal "can't quote Object", e.message
       end
 
       def test_quote_string_no_column
-        assert_equal "'lo\\\\l'", @quoter.quote('lo\l', nil)
+        assert_equal "'lo\\\\l'", @quoter.quote('lo\l')
       end
 
       def test_quote_as_mb_chars_no_column
         string = ActiveSupport::Multibyte::Chars.new('lo\l')
-        assert_equal "'lo\\\\l'", @quoter.quote(string, nil)
-      end
-
-      def test_string_with_crazy_column
-        assert_equal "'lo\\\\l'", @quoter.quote('lo\l')
+        assert_equal "'lo\\\\l'", @quoter.quote(string)
       end
 
       def test_quote_duration
         assert_equal "1800", @quoter.quote(30.minutes)
       end
     end
+
+    class TypeCastingTest < ActiveRecord::TestCase
+      def setup
+        @conn = ActiveRecord::Base.connection
+      end
+
+      def test_type_cast_symbol
+        assert_equal "foo", @conn.type_cast(:foo)
+      end
+
+      def test_type_cast_date
+        date = Date.today
+        if current_adapter?(:Mysql2Adapter)
+          expected = date
+        else
+          expected = @conn.quoted_date(date)
+        end
+        assert_equal expected, @conn.type_cast(date)
+      end
+
+      def test_type_cast_time
+        time = Time.now
+        if current_adapter?(:Mysql2Adapter)
+          expected = time
+        else
+          expected = @conn.quoted_date(time)
+        end
+        assert_equal expected, @conn.type_cast(time)
+      end
+
+      def test_type_cast_numeric
+        assert_equal 10, @conn.type_cast(10)
+        assert_equal 2.2, @conn.type_cast(2.2)
+      end
+
+      def test_type_cast_nil
+        assert_nil @conn.type_cast(nil)
+      end
+
+      def test_type_cast_unknown_should_raise_error
+        obj = Class.new.new
+        assert_raise(TypeError) { @conn.type_cast(obj) }
+      end
+    end
+
+    class QuoteBooleanTest < ActiveRecord::TestCase
+      def setup
+        @connection = ActiveRecord::Base.connection
+      end
+
+      def test_quote_returns_frozen_string
+        assert_predicate @connection.quote(true), :frozen?
+        assert_predicate @connection.quote(false), :frozen?
+      end
+
+      def test_type_cast_returns_frozen_value
+        assert_predicate @connection.type_cast(true), :frozen?
+        assert_predicate @connection.type_cast(false), :frozen?
+      end
+    end
+
+    if subsecond_precision_supported?
+      class QuoteARBaseTest < ActiveRecord::TestCase
+        class DatetimePrimaryKey < ActiveRecord::Base
+        end
+
+        def setup
+          @time = ::Time.utc(2017, 2, 14, 12, 34, 56, 789999)
+          @connection = ActiveRecord::Base.connection
+          @connection.create_table :datetime_primary_keys, id: :datetime, precision: 3, force: true
+        end
+
+        def teardown
+          @connection.drop_table :datetime_primary_keys, if_exists: true
+        end
+
+        def test_quote_ar_object
+          value = DatetimePrimaryKey.new(id: @time)
+          assert_equal "'2017-02-14 12:34:56.789000'",  @connection.quote(value)
+        end
+
+        def test_type_cast_ar_object
+          value = DatetimePrimaryKey.new(id: @time)
+          assert_equal @connection.type_cast(value.id),  @connection.type_cast(value)
+        end
+      end
+    end
   end
 end
diff --git a/activerecord/test/cases/readonly_test.rb b/activerecord/test/cases/readonly_test.rb
index 5f6eb41240..d1b85cb4ef 100644
--- a/activerecord/test/cases/readonly_test.rb
+++ b/activerecord/test/cases/readonly_test.rb
@@ -1,16 +1,18 @@
+# frozen_string_literal: true
+
 require "cases/helper"
-require 'models/author'
-require 'models/post'
-require 'models/comment'
-require 'models/developer'
-require 'models/computer'
-require 'models/project'
-require 'models/reader'
-require 'models/person'
-require 'models/ship'
+require "models/author"
+require "models/post"
+require "models/comment"
+require "models/developer"
+require "models/computer"
+require "models/project"
+require "models/reader"
+require "models/person"
+require "models/ship"
 
 class ReadOnlyTest < ActiveRecord::TestCase
-  fixtures :authors, :posts, :comments, :developers, :projects, :developers_projects, :people, :readers
+  fixtures :authors, :author_addresses, :posts, :comments, :developers, :projects, :developers_projects, :people, :readers
 
   def test_cant_save_readonly_record
     dev = Developer.find(1)
@@ -20,9 +22,9 @@ class ReadOnlyTest < ActiveRecord::TestCase
     assert dev.readonly?
 
     assert_nothing_raised do
-      dev.name = 'Luscious forbidden fruit.'
+      dev.name = "Luscious forbidden fruit."
       assert !dev.save
-      dev.name = 'Forbidden.'
+      dev.name = "Forbidden."
     end
 
     e = assert_raise(ActiveRecord::ReadOnlyRecord) { dev.save  }
@@ -35,7 +37,6 @@ class ReadOnlyTest < ActiveRecord::TestCase
     assert_equal "Developer is marked as readonly", e.message
   end
 
-
   def test_find_with_readonly_option
     Developer.all.each { |d| assert !d.readonly? }
     Developer.readonly(false).each { |d| assert !d.readonly? }
@@ -44,11 +45,11 @@ class ReadOnlyTest < ActiveRecord::TestCase
   end
 
   def test_find_with_joins_option_does_not_imply_readonly
-    Developer.joins('  ').each { |d| assert_not d.readonly? }
-    Developer.joins('  ').readonly(true).each { |d| assert d.readonly? }
+    Developer.joins("  ").each { |d| assert_not d.readonly? }
+    Developer.joins("  ").readonly(true).each { |d| assert d.readonly? }
 
-    Developer.joins(', projects').each { |d| assert_not d.readonly? }
-    Developer.joins(', projects').readonly(true).each { |d| assert d.readonly? }
+    Developer.joins(", projects").each { |d| assert_not d.readonly? }
+    Developer.joins(", projects").readonly(true).each { |d| assert d.readonly? }
   end
 
   def test_has_many_find_readonly
@@ -77,13 +78,13 @@ class ReadOnlyTest < ActiveRecord::TestCase
   end
 
   def test_readonly_scoping
-    Post.where('1=1').scoping do
+    Post.where("1=1").scoping do
       assert !Post.find(1).readonly?
       assert Post.readonly(true).find(1).readonly?
       assert !Post.readonly(false).find(1).readonly?
     end
 
-    Post.joins('   ').scoping do
+    Post.joins("   ").scoping do
       assert !Post.find(1).readonly?
       assert Post.readonly.find(1).readonly?
       assert !Post.readonly(false).find(1).readonly?
@@ -92,7 +93,7 @@ class ReadOnlyTest < ActiveRecord::TestCase
     # Oracle barfs on this because the join includes unqualified and
     # conflicting column names
     unless current_adapter?(:OracleAdapter)
-      Post.joins(', developers').scoping do
+      Post.joins(", developers").scoping do
         assert_not Post.find(1).readonly?
         assert Post.readonly.find(1).readonly?
         assert !Post.readonly(false).find(1).readonly?
diff --git a/activerecord/test/cases/reaper_test.rb b/activerecord/test/cases/reaper_test.rb
index cccfc6774e..6c7727ab1b 100644
--- a/activerecord/test/cases/reaper_test.rb
+++ b/activerecord/test/cases/reaper_test.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require "cases/helper"
 
 module ActiveRecord
@@ -16,6 +18,7 @@ module ActiveRecord
 
       class FakePool
         attr_reader :reaped
+        attr_reader :flushed
 
         def initialize
           @reaped = false
@@ -24,6 +27,10 @@ module ActiveRecord
         def reap
           @reaped = true
         end
+
+        def flush
+          @flushed = true
+        end
       end
 
       # A reaper with nil time should never reap connections
@@ -45,6 +52,7 @@ module ActiveRecord
           Thread.pass
         end
         assert fp.reaped
+        assert fp.flushed
       end
 
       def test_pool_has_reaper
@@ -60,7 +68,7 @@ module ActiveRecord
 
       def test_connection_pool_starts_reaper
         spec = ActiveRecord::Base.connection_pool.spec.dup
-        spec.config[:reaping_frequency] = '0.0001'
+        spec.config[:reaping_frequency] = "0.0001"
 
         pool = ConnectionPool.new spec
 
diff --git a/activerecord/test/cases/reflection_test.rb b/activerecord/test/cases/reflection_test.rb
index 710c86b151..44055e5ab6 100644
--- a/activerecord/test/cases/reflection_test.rb
+++ b/activerecord/test/cases/reflection_test.rb
@@ -1,30 +1,31 @@
+# frozen_string_literal: true
+
 require "cases/helper"
-require 'models/topic'
-require 'models/customer'
-require 'models/company'
-require 'models/company_in_module'
-require 'models/ship'
-require 'models/pirate'
-require 'models/price_estimate'
-require 'models/essay'
-require 'models/author'
-require 'models/organization'
-require 'models/post'
-require 'models/tagging'
-require 'models/category'
-require 'models/book'
-require 'models/subscriber'
-require 'models/subscription'
-require 'models/tag'
-require 'models/sponsor'
-require 'models/edge'
-require 'models/hotel'
-require 'models/chef'
-require 'models/department'
-require 'models/cake_designer'
-require 'models/drink_designer'
-require 'models/mocktail_designer'
-require 'models/recipe'
+require "models/topic"
+require "models/customer"
+require "models/company"
+require "models/company_in_module"
+require "models/ship"
+require "models/pirate"
+require "models/price_estimate"
+require "models/essay"
+require "models/author"
+require "models/organization"
+require "models/post"
+require "models/tagging"
+require "models/category"
+require "models/book"
+require "models/subscriber"
+require "models/subscription"
+require "models/tag"
+require "models/sponsor"
+require "models/edge"
+require "models/hotel"
+require "models/chef"
+require "models/department"
+require "models/cake_designer"
+require "models/drink_designer"
+require "models/recipe"
 
 class ReflectionTest < ActiveRecord::TestCase
   include ActiveRecord::Reflection
@@ -86,8 +87,8 @@ class ReflectionTest < ActiveRecord::TestCase
     column = @first.column_for_attribute("attribute_that_doesnt_exist")
     assert_instance_of ActiveRecord::ConnectionAdapters::NullColumn, column
     assert_equal "attribute_that_doesnt_exist", column.name
-    assert_equal nil, column.sql_type
-    assert_equal nil, column.type
+    assert_nil column.sql_type
+    assert_nil column.type
   end
 
   def test_non_existent_types_are_identity_types
@@ -100,7 +101,13 @@ class ReflectionTest < ActiveRecord::TestCase
   end
 
   def test_reflection_klass_for_nested_class_name
-    reflection = ActiveRecord::Reflection.create(:has_many, nil, nil, { :class_name => 'MyApplication::Business::Company' }, ActiveRecord::Base)
+    reflection = ActiveRecord::Reflection.create(
+      :has_many,
+      nil,
+      nil,
+      { class_name: "MyApplication::Business::Company" },
+      Customer
+    )
     assert_nothing_raised do
       assert_equal MyApplication::Business::Company, reflection.klass
     end
@@ -108,28 +115,28 @@ class ReflectionTest < ActiveRecord::TestCase
 
   def test_irregular_reflection_class_name
     ActiveSupport::Inflector.inflections do |inflect|
-      inflect.irregular 'plural_irregular', 'plurales_irregulares'
+      inflect.irregular "plural_irregular", "plurales_irregulares"
     end
-    reflection = ActiveRecord::Reflection.create(:has_many, 'plurales_irregulares', nil, {}, ActiveRecord::Base)
-    assert_equal 'PluralIrregular', reflection.class_name
+    reflection = ActiveRecord::Reflection.create(:has_many, "plurales_irregulares", nil, {}, ActiveRecord::Base)
+    assert_equal "PluralIrregular", reflection.class_name
   end
 
   def test_aggregation_reflection
     reflection_for_address = AggregateReflection.new(
-      :address, nil, { :mapping => [ %w(address_street street), %w(address_city city), %w(address_country country) ] }, Customer
+      :address, nil, { mapping: [ %w(address_street street), %w(address_city city), %w(address_country country) ] }, Customer
     )
 
     reflection_for_balance = AggregateReflection.new(
-      :balance, nil, { :class_name => "Money", :mapping => %w(balance amount) }, Customer
+      :balance, nil, { class_name: "Money", mapping: %w(balance amount) }, Customer
     )
 
     reflection_for_gps_location = AggregateReflection.new(
-      :gps_location, nil, { }, Customer
+      :gps_location, nil, {}, Customer
     )
 
-    assert Customer.reflect_on_all_aggregations.include?(reflection_for_gps_location)
-    assert Customer.reflect_on_all_aggregations.include?(reflection_for_balance)
-    assert Customer.reflect_on_all_aggregations.include?(reflection_for_address)
+    assert_includes Customer.reflect_on_all_aggregations, reflection_for_gps_location
+    assert_includes Customer.reflect_on_all_aggregations, reflection_for_balance
+    assert_includes Customer.reflect_on_all_aggregations, reflection_for_address
 
     assert_equal reflection_for_address, Customer.reflect_on_aggregation(:address)
 
@@ -148,31 +155,31 @@ class ReflectionTest < ActiveRecord::TestCase
   end
 
   def test_has_many_reflection
-    reflection_for_clients = ActiveRecord::Reflection.create(:has_many, :clients, nil, { :order => "id", :dependent => :destroy }, Firm)
+    reflection_for_clients = ActiveRecord::Reflection.create(:has_many, :clients, nil, { order: "id", dependent: :destroy }, Firm)
 
     assert_equal reflection_for_clients, Firm.reflect_on_association(:clients)
 
     assert_equal Client, Firm.reflect_on_association(:clients).klass
-    assert_equal 'companies', Firm.reflect_on_association(:clients).table_name
+    assert_equal "companies", Firm.reflect_on_association(:clients).table_name
 
     assert_equal Client, Firm.reflect_on_association(:clients_of_firm).klass
-    assert_equal 'companies', Firm.reflect_on_association(:clients_of_firm).table_name
+    assert_equal "companies", Firm.reflect_on_association(:clients_of_firm).table_name
   end
 
   def test_has_one_reflection
-    reflection_for_account = ActiveRecord::Reflection.create(:has_one, :account, nil, { :foreign_key => "firm_id", :dependent => :destroy }, Firm)
+    reflection_for_account = ActiveRecord::Reflection.create(:has_one, :account, nil, { foreign_key: "firm_id", dependent: :destroy }, Firm)
     assert_equal reflection_for_account, Firm.reflect_on_association(:account)
 
     assert_equal Account, Firm.reflect_on_association(:account).klass
-    assert_equal 'accounts', Firm.reflect_on_association(:account).table_name
+    assert_equal "accounts", Firm.reflect_on_association(:account).table_name
   end
 
   def test_belongs_to_inferred_foreign_key_from_assoc_name
     Company.belongs_to :foo
     assert_equal "foo_id", Company.reflect_on_association(:foo).foreign_key
-    Company.belongs_to :bar, :class_name => "Xyzzy"
+    Company.belongs_to :bar, class_name: "Xyzzy"
     assert_equal "bar_id", Company.reflect_on_association(:bar).foreign_key
-    Company.belongs_to :baz, :class_name => "Xyzzy", :foreign_key => "xyzzy_id"
+    Company.belongs_to :baz, class_name: "Xyzzy", foreign_key: "xyzzy_id"
     assert_equal "xyzzy_id", Company.reflect_on_association(:baz).foreign_key
   end
 
@@ -181,45 +188,45 @@ class ReflectionTest < ActiveRecord::TestCase
 
     assert_reflection MyApplication::Business::Firm,
       :clients_of_firm,
-      :klass      => MyApplication::Business::Client,
-      :class_name => 'Client',
-      :table_name => 'companies'
+      klass: MyApplication::Business::Client,
+      class_name: "Client",
+      table_name: "companies"
 
     assert_reflection MyApplication::Billing::Account,
       :firm,
-      :klass      => MyApplication::Business::Firm,
-      :class_name => 'MyApplication::Business::Firm',
-      :table_name => 'companies'
+      klass: MyApplication::Business::Firm,
+      class_name: "MyApplication::Business::Firm",
+      table_name: "companies"
 
     assert_reflection MyApplication::Billing::Account,
       :qualified_billing_firm,
-      :klass      => MyApplication::Billing::Firm,
-      :class_name => 'MyApplication::Billing::Firm',
-      :table_name => 'companies'
+      klass: MyApplication::Billing::Firm,
+      class_name: "MyApplication::Billing::Firm",
+      table_name: "companies"
 
     assert_reflection MyApplication::Billing::Account,
       :unqualified_billing_firm,
-      :klass      => MyApplication::Billing::Firm,
-      :class_name => 'Firm',
-      :table_name => 'companies'
+      klass: MyApplication::Billing::Firm,
+      class_name: "Firm",
+      table_name: "companies"
 
     assert_reflection MyApplication::Billing::Account,
       :nested_qualified_billing_firm,
-      :klass      => MyApplication::Billing::Nested::Firm,
-      :class_name => 'MyApplication::Billing::Nested::Firm',
-      :table_name => 'companies'
+      klass: MyApplication::Billing::Nested::Firm,
+      class_name: "MyApplication::Billing::Nested::Firm",
+      table_name: "companies"
 
     assert_reflection MyApplication::Billing::Account,
       :nested_unqualified_billing_firm,
-      :klass      => MyApplication::Billing::Nested::Firm,
-      :class_name => 'Nested::Firm',
-      :table_name => 'companies'
+      klass: MyApplication::Billing::Nested::Firm,
+      class_name: "Nested::Firm",
+      table_name: "companies"
   ensure
     ActiveRecord::Base.store_full_sti_class = true
   end
 
   def test_reflection_should_not_raise_error_when_compared_to_other_object
-    assert_not_equal Object.new, Firm._reflections['clients']
+    assert_not_equal Object.new, Firm._reflections["clients"]
   end
 
   def test_reflections_should_return_keys_as_strings
@@ -227,7 +234,7 @@ class ReflectionTest < ActiveRecord::TestCase
   end
 
   def test_has_and_belongs_to_many_reflection
-    assert_equal :has_and_belongs_to_many, Category.reflections['posts'].macro
+    assert_equal :has_and_belongs_to_many, Category.reflections["posts"].macro
     assert_equal :posts, Category.reflect_on_all_associations(:has_and_belongs_to_many).first.name
   end
 
@@ -246,28 +253,6 @@ class ReflectionTest < ActiveRecord::TestCase
     assert_equal expected, actual
   end
 
-  def test_scope_chain
-    expected = [
-      [Tagging.reflect_on_association(:tag).scope, Post.reflect_on_association(:first_blue_tags).scope],
-      [Post.reflect_on_association(:first_taggings).scope],
-      [Author.reflect_on_association(:misc_posts).scope]
-    ]
-    actual = Author.reflect_on_association(:misc_post_first_blue_tags).scope_chain
-    assert_equal expected, actual
-
-    expected = [
-      [
-        Tagging.reflect_on_association(:blue_tag).scope,
-        Post.reflect_on_association(:first_blue_tags_2).scope,
-        Author.reflect_on_association(:misc_post_first_blue_tags_2).scope
-      ],
-      [],
-      []
-    ]
-    actual = Author.reflect_on_association(:misc_post_first_blue_tags_2).scope_chain
-    assert_equal expected, actual
-  end
-
   def test_scope_chain_does_not_interfere_with_hmt_with_polymorphic_case
     @hotel = Hotel.create!
     @department = @hotel.departments.create!
@@ -345,9 +330,16 @@ class ReflectionTest < ActiveRecord::TestCase
     assert_raises(ActiveRecord::UnknownPrimaryKey) { reflection.active_record_primary_key }
   end
 
+  def test_type
+    assert_equal "taggable_type", Post.reflect_on_association(:taggings).type.to_s
+    assert_equal "imageable_class", Post.reflect_on_association(:images).type.to_s
+    assert_nil Post.reflect_on_association(:readers).type
+  end
+
   def test_foreign_type
     assert_equal "sponsorable_type", Sponsor.reflect_on_association(:sponsorable).foreign_type.to_s
     assert_equal "sponsorable_type", Sponsor.reflect_on_association(:thing).foreign_type.to_s
+    assert_nil Sponsor.reflect_on_association(:sponsor_club).foreign_type
   end
 
   def test_collection_association
@@ -366,21 +358,21 @@ class ReflectionTest < ActiveRecord::TestCase
   end
 
   def test_always_validate_association_if_explicit
-    assert ActiveRecord::Reflection.create(:has_one, :client, nil, { :validate => true }, Firm).validate?
-    assert ActiveRecord::Reflection.create(:belongs_to, :client, nil, { :validate => true }, Firm).validate?
-    assert ActiveRecord::Reflection.create(:has_many, :clients, nil, { :validate => true }, Firm).validate?
+    assert ActiveRecord::Reflection.create(:has_one, :client, nil, { validate: true }, Firm).validate?
+    assert ActiveRecord::Reflection.create(:belongs_to, :client, nil, { validate: true }, Firm).validate?
+    assert ActiveRecord::Reflection.create(:has_many, :clients, nil, { validate: true }, Firm).validate?
   end
 
   def test_validate_association_if_autosave
-    assert ActiveRecord::Reflection.create(:has_one, :client, nil, { :autosave => true }, Firm).validate?
-    assert ActiveRecord::Reflection.create(:belongs_to, :client, nil, { :autosave => true }, Firm).validate?
-    assert ActiveRecord::Reflection.create(:has_many, :clients, nil, { :autosave => true }, Firm).validate?
+    assert ActiveRecord::Reflection.create(:has_one, :client, nil, { autosave: true }, Firm).validate?
+    assert ActiveRecord::Reflection.create(:belongs_to, :client, nil, { autosave: true }, Firm).validate?
+    assert ActiveRecord::Reflection.create(:has_many, :clients, nil, { autosave: true }, Firm).validate?
   end
 
   def test_never_validate_association_if_explicit
-    assert !ActiveRecord::Reflection.create(:has_one, :client, nil, { :autosave => true, :validate => false }, Firm).validate?
-    assert !ActiveRecord::Reflection.create(:belongs_to, :client, nil, { :autosave => true, :validate => false }, Firm).validate?
-    assert !ActiveRecord::Reflection.create(:has_many, :clients, nil, { :autosave => true, :validate => false }, Firm).validate?
+    assert !ActiveRecord::Reflection.create(:has_one, :client, nil, { autosave: true, validate: false }, Firm).validate?
+    assert !ActiveRecord::Reflection.create(:belongs_to, :client, nil, { autosave: true, validate: false }, Firm).validate?
+    assert !ActiveRecord::Reflection.create(:has_many, :clients, nil, { autosave: true, validate: false }, Firm).validate?
   end
 
   def test_foreign_key
@@ -388,73 +380,74 @@ class ReflectionTest < ActiveRecord::TestCase
     assert_equal "category_id", Post.reflect_on_association(:categorizations).foreign_key.to_s
   end
 
-  def test_through_reflection_scope_chain_does_not_modify_other_reflections
-    orig_conds = Post.reflect_on_association(:first_blue_tags_2).scope_chain.inspect
-    Author.reflect_on_association(:misc_post_first_blue_tags_2).scope_chain
-    assert_equal orig_conds, Post.reflect_on_association(:first_blue_tags_2).scope_chain.inspect
-  end
-
   def test_symbol_for_class_name
     assert_equal Client, Firm.reflect_on_association(:unsorted_clients_with_symbol).klass
   end
 
+  def test_class_for_class_name
+    error = assert_raises(ArgumentError) do
+      ActiveRecord::Reflection.create(:has_many, :clients, nil, { class_name: Client }, Firm)
+    end
+    assert_equal "A class was passed to `:class_name` but we are expecting a string.", error.message
+  end
+
   def test_join_table
-    category = Struct.new(:table_name, :pluralize_table_names).new('categories', true)
-    product = Struct.new(:table_name, :pluralize_table_names).new('products', true)
+    category = Struct.new(:table_name, :pluralize_table_names).new("categories", true)
+    product = Struct.new(:table_name, :pluralize_table_names).new("products", true)
 
     reflection = ActiveRecord::Reflection.create(:has_many, :categories, nil, {}, product)
     reflection.stub(:klass, category) do
-      assert_equal 'categories_products', reflection.join_table
+      assert_equal "categories_products", reflection.join_table
     end
 
     reflection = ActiveRecord::Reflection.create(:has_many, :products, nil, {}, category)
     reflection.stub(:klass, product) do
-      assert_equal 'categories_products', reflection.join_table
+      assert_equal "categories_products", reflection.join_table
     end
   end
 
   def test_join_table_with_common_prefix
-    category = Struct.new(:table_name, :pluralize_table_names).new('catalog_categories', true)
-    product = Struct.new(:table_name, :pluralize_table_names).new('catalog_products', true)
+    category = Struct.new(:table_name, :pluralize_table_names).new("catalog_categories", true)
+    product = Struct.new(:table_name, :pluralize_table_names).new("catalog_products", true)
 
     reflection = ActiveRecord::Reflection.create(:has_many, :categories, nil, {}, product)
     reflection.stub(:klass, category) do
-      assert_equal 'catalog_categories_products', reflection.join_table
+      assert_equal "catalog_categories_products", reflection.join_table
     end
 
     reflection = ActiveRecord::Reflection.create(:has_many, :products, nil, {}, category)
     reflection.stub(:klass, product) do
-      assert_equal 'catalog_categories_products', reflection.join_table
+      assert_equal "catalog_categories_products", reflection.join_table
     end
   end
 
   def test_join_table_with_different_prefix
-    category = Struct.new(:table_name, :pluralize_table_names).new('catalog_categories', true)
-    page = Struct.new(:table_name, :pluralize_table_names).new('content_pages', true)
+    category = Struct.new(:table_name, :pluralize_table_names).new("catalog_categories", true)
+    page = Struct.new(:table_name, :pluralize_table_names).new("content_pages", true)
 
     reflection = ActiveRecord::Reflection.create(:has_many, :categories, nil, {}, page)
     reflection.stub(:klass, category) do
-      assert_equal 'catalog_categories_content_pages', reflection.join_table
+      assert_equal "catalog_categories_content_pages", reflection.join_table
     end
 
     reflection = ActiveRecord::Reflection.create(:has_many, :pages, nil, {}, category)
     reflection.stub(:klass, page) do
-      assert_equal 'catalog_categories_content_pages', reflection.join_table
+      assert_equal "catalog_categories_content_pages", reflection.join_table
     end
   end
 
   def test_join_table_can_be_overridden
-    category = Struct.new(:table_name, :pluralize_table_names).new('categories', true)
-    product = Struct.new(:table_name, :pluralize_table_names).new('products', true)
+    category = Struct.new(:table_name, :pluralize_table_names).new("categories", true)
+    product = Struct.new(:table_name, :pluralize_table_names).new("products", true)
 
-    reflection = ActiveRecord::Reflection.create(:has_many, :categories, nil, { :join_table => 'product_categories' }, product)
+    reflection = ActiveRecord::Reflection.create(:has_many, :categories, nil, { join_table: "product_categories" }, product)
     reflection.stub(:klass, category) do
-      assert_equal 'product_categories', reflection.join_table
+      assert_equal "product_categories", reflection.join_table
     end
 
-    reflection = ActiveRecord::Reflection.create(:has_many, :products, nil, { :join_table => 'product_categories' }, category)
+    reflection = ActiveRecord::Reflection.create(:has_many, :products, nil, { join_table: "product_categories" }, category)
     reflection.stub(:klass, product) do
-      assert_equal 'product_categories', reflection.join_table
+      assert_equal "product_categories", reflection.join_table
     end
   end
 
@@ -474,7 +467,7 @@ class ReflectionTest < ActiveRecord::TestCase
     department.chefs.create!
 
     assert_nothing_raised do
-      assert_equal department.chefs, Hotel.includes(['departments' => 'chefs']).first.chefs
+      assert_equal department.chefs, Hotel.includes(["departments" => "chefs"]).first.chefs
     end
   end
 
diff --git a/activerecord/test/cases/relation/delegation_test.rb b/activerecord/test/cases/relation/delegation_test.rb
index f0e07e0731..2696d1bb00 100644
--- a/activerecord/test/cases/relation/delegation_test.rb
+++ b/activerecord/test/cases/relation/delegation_test.rb
@@ -1,38 +1,19 @@
-require 'cases/helper'
-require 'models/post'
-require 'models/comment'
+# frozen_string_literal: true
 
-module ActiveRecord
-  class DelegationTest < ActiveRecord::TestCase
-    fixtures :posts
-
-    def call_method(target, method)
-      method_arity = target.to_a.method(method).arity
-
-      if method_arity.zero?
-        target.public_send(method)
-      elsif method_arity < 0
-        if method == :shuffle!
-          target.public_send(method)
-        else
-          target.public_send(method, 1)
-        end
-       elsif method_arity == 1
-        target.public_send(method, 1)
-      else
-        raise NotImplementedError
-      end
-    end
-  end
+require "cases/helper"
+require "models/post"
+require "models/comment"
 
-  module DelegationWhitelistBlacklistTests
+module ActiveRecord
+  module DelegationWhitelistTests
     ARRAY_DELEGATES = [
       :+, :-, :|, :&, :[], :shuffle,
       :all?, :collect, :compact, :detect, :each, :each_cons, :each_with_index,
       :exclude?, :find_all, :flat_map, :group_by, :include?, :length,
-      :map, :none?, :one?, :partition, :reject, :reverse,
-      :sample, :second, :sort, :sort_by, :third,
-      :to_ary, :to_set, :to_xml, :to_yaml, :join
+      :map, :none?, :one?, :partition, :reject, :reverse, :rotate,
+      :sample, :second, :sort, :sort_by, :slice, :third, :index, :rindex,
+      :to_ary, :to_set, :to_xml, :to_yaml, :join,
+      :in_groups, :in_groups_of, :to_sentence, :to_formatted_s, :as_json
     ]
 
     ARRAY_DELEGATES.each do |method|
@@ -42,18 +23,32 @@ module ActiveRecord
     end
   end
 
-  class DelegationAssociationTest < DelegationTest
-    include DelegationWhitelistBlacklistTests
+  module DeprecatedArelDelegationTests
+    AREL_METHODS = [
+      :with, :orders, :froms, :project, :projections, :taken, :constraints, :exists, :locked, :where_sql,
+      :ast, :source, :join_sources, :to_dot, :create_insert, :create_true, :create_false
+    ]
+
+    def test_deprecate_arel_delegation
+      AREL_METHODS.each do |method|
+        assert_deprecated { target.public_send(method) }
+        assert_deprecated { target.public_send(method) }
+      end
+    end
+  end
+
+  class DelegationAssociationTest < ActiveRecord::TestCase
+    include DelegationWhitelistTests
+    include DeprecatedArelDelegationTests
 
     def target
-      Post.first.comments
+      Post.new.comments
     end
   end
 
-  class DelegationRelationTest < DelegationTest
-    include DelegationWhitelistBlacklistTests
-
-    fixtures :comments
+  class DelegationRelationTest < ActiveRecord::TestCase
+    include DelegationWhitelistTests
+    include DeprecatedArelDelegationTests
 
     def target
       Comment.all
diff --git a/activerecord/test/cases/relation/merging_test.rb b/activerecord/test/cases/relation/merging_test.rb
index 60a806c05a..b68b3723f6 100644
--- a/activerecord/test/cases/relation/merging_test.rb
+++ b/activerecord/test/cases/relation/merging_test.rb
@@ -1,27 +1,29 @@
-require 'cases/helper'
-require 'models/author'
-require 'models/comment'
-require 'models/developer'
-require 'models/computer'
-require 'models/post'
-require 'models/project'
-require 'models/rating'
+# frozen_string_literal: true
+
+require "cases/helper"
+require "models/author"
+require "models/comment"
+require "models/developer"
+require "models/computer"
+require "models/post"
+require "models/project"
+require "models/rating"
 
 class RelationMergingTest < ActiveRecord::TestCase
-  fixtures :developers, :comments, :authors, :posts
+  fixtures :developers, :comments, :authors, :author_addresses, :posts
 
   def test_relation_merging
-    devs = Developer.where("salary >= 80000").merge(Developer.limit(2)).merge(Developer.order('id ASC').where("id < 3"))
+    devs = Developer.where("salary >= 80000").merge(Developer.limit(2)).merge(Developer.order("id ASC").where("id < 3"))
     assert_equal [developers(:david), developers(:jamis)], devs.to_a
 
-    dev_with_count = Developer.limit(1).merge(Developer.order('id DESC')).merge(Developer.select('developers.*'))
+    dev_with_count = Developer.limit(1).merge(Developer.order("id DESC")).merge(Developer.select("developers.*"))
     assert_equal [developers(:poor_jamis)], dev_with_count.to_a
   end
 
   def test_relation_to_sql
     post = Post.first
     sql = post.comments.to_sql
-    assert_match(/.?post_id.? = #{post.id}\Z/i, sql)
+    assert_match(/.?post_id.? = #{post.id}\z/i, sql)
   end
 
   def test_relation_merging_with_arel_equalities_keeps_last_equality
@@ -34,10 +36,10 @@ class RelationMergingTest < ActiveRecord::TestCase
   def test_relation_merging_with_arel_equalities_keeps_last_equality_with_non_attribute_left_hand
     salary_attr = Developer.arel_table[:salary]
     devs = Developer.where(
-      Arel::Nodes::NamedFunction.new('abs', [salary_attr]).eq(80000)
+      Arel::Nodes::NamedFunction.new("abs", [salary_attr]).eq(80000)
     ).merge(
       Developer.where(
-        Arel::Nodes::NamedFunction.new('abs', [salary_attr]).eq(9000)
+        Arel::Nodes::NamedFunction.new("abs", [salary_attr]).eq(9000)
       )
     )
     assert_equal [developers(:poor_jamis)], devs.to_a
@@ -45,8 +47,8 @@ class RelationMergingTest < ActiveRecord::TestCase
 
   def test_relation_merging_with_eager_load
     relations = []
-    relations << Post.order('comments.id DESC').merge(Post.eager_load(:last_comment)).merge(Post.all)
-    relations << Post.eager_load(:last_comment).merge(Post.order('comments.id DESC')).merge(Post.all)
+    relations << Post.order("comments.id DESC").merge(Post.eager_load(:last_comment)).merge(Post.all)
+    relations << Post.eager_load(:last_comment).merge(Post.order("comments.id DESC")).merge(Post.all)
 
     relations.each do |posts|
       post = posts.find { |p| p.id == 1 }
@@ -56,7 +58,7 @@ class RelationMergingTest < ActiveRecord::TestCase
 
   def test_relation_merging_with_locks
     devs = Developer.lock.where("salary >= 80000").order("id DESC").merge(Developer.limit(2))
-    assert devs.locked.present?
+    assert devs.locked?
   end
 
   def test_relation_merging_with_preload
@@ -66,29 +68,27 @@ class RelationMergingTest < ActiveRecord::TestCase
   end
 
   def test_relation_merging_with_joins
-    comments = Comment.joins(:post).where(:body => 'Thank you for the welcome').merge(Post.where(:body => 'Such a lovely day'))
+    comments = Comment.joins(:post).where(body: "Thank you for the welcome").merge(Post.where(body: "Such a lovely day"))
     assert_equal 1, comments.count
   end
 
   def test_relation_merging_with_association
     assert_queries(2) do  # one for loading post, and another one merged query
-      post = Post.where(:body => 'Such a lovely day').first
-      comments = Comment.where(:body => 'Thank you for the welcome').merge(post.comments)
+      post = Post.where(body: "Such a lovely day").first
+      comments = Comment.where(body: "Thank you for the welcome").merge(post.comments)
       assert_equal 1, comments.count
     end
   end
 
   test "merge collapses wheres from the LHS only" do
-    left  = Post.where(title: "omg").where(comments_count: 1)
+    left = Post.where(title: "omg").where(comments_count: 1)
     right = Post.where(title: "wtf").where(title: "bbq")
 
-    expected = [left.bound_attributes[1]] + right.bound_attributes
-    merged   = left.merge(right)
+    merged = left.merge(right)
 
-    assert_equal expected, merged.bound_attributes
-    assert !merged.to_sql.include?("omg")
-    assert merged.to_sql.include?("wtf")
-    assert merged.to_sql.include?("bbq")
+    assert_not_includes merged.to_sql, "omg"
+    assert_includes merged.to_sql, "wtf"
+    assert_includes merged.to_sql, "bbq"
   end
 
   def test_merging_reorders_bind_params
@@ -114,7 +114,7 @@ class RelationMergingTest < ActiveRecord::TestCase
 end
 
 class MergingDifferentRelationsTest < ActiveRecord::TestCase
-  fixtures :posts, :authors, :developers
+  fixtures :posts, :authors, :author_addresses, :developers
 
   test "merging where relations" do
     hello_by_bob = Post.where(body: "hello").joins(:author).
@@ -143,7 +143,7 @@ class MergingDifferentRelationsTest < ActiveRecord::TestCase
     assert_equal ["Mary", "Mary", "Mary", "David"], posts_by_author_name
   end
 
-  test "relation merging (using a proc  argument)" do
+  test "relation merging (using a proc argument)" do
     dev = Developer.where(name: "Jamis").first
 
     comment_1 = dev.comments.create!(body: "I'm Jamis", post: Post.first)
diff --git a/activerecord/test/cases/relation/mutation_test.rb b/activerecord/test/cases/relation/mutation_test.rb
index ffb2da7a26..ad3700b73a 100644
--- a/activerecord/test/cases/relation/mutation_test.rb
+++ b/activerecord/test/cases/relation/mutation_test.rb
@@ -1,42 +1,11 @@
-require 'cases/helper'
-require 'models/post'
+# frozen_string_literal: true
 
-module ActiveRecord
-  class RelationMutationTest < ActiveSupport::TestCase
-    class FakeKlass < Struct.new(:table_name, :name)
-      extend ActiveRecord::Delegation::DelegateCache
-      inherited self
-
-      def connection
-        Post.connection
-      end
-
-      def relation_delegate_class(klass)
-        self.class.relation_delegate_class(klass)
-      end
-
-      def attribute_alias?(name)
-        false
-      end
-
-      def sanitize_sql(sql)
-        sql
-      end
-
-      def sanitize_sql_for_order(sql)
-        sql
-      end
-
-      def arel_attribute(name, table)
-        table[name]
-      end
-    end
-
-    def relation
-      @relation ||= Relation.new FakeKlass.new('posts'), Post.arel_table, Post.predicate_builder
-    end
+require "cases/helper"
+require "models/post"
 
-    (Relation::MULTI_VALUE_METHODS - [:references, :extending, :order, :unscope, :select, :left_joins]).each do |method|
+module ActiveRecord
+  class RelationMutationTest < ActiveRecord::TestCase
+    (Relation::MULTI_VALUE_METHODS - [:references, :extending, :order, :unscope, :select]).each do |method|
       test "##{method}!" do
         assert relation.public_send("#{method}!", :foo).equal?(relation)
         assert_equal [:foo], relation.public_send("#{method}_values")
@@ -44,16 +13,16 @@ module ActiveRecord
     end
 
     test "#_select!" do
-      assert relation.public_send("_select!", :foo).equal?(relation)
-      assert_equal [:foo], relation.public_send("select_values")
+      assert relation._select!(:foo).equal?(relation)
+      assert_equal [:foo], relation.select_values
     end
 
-    test '#order!' do
-      assert relation.order!('name ASC').equal?(relation)
-      assert_equal ['name ASC'], relation.order_values
+    test "#order!" do
+      assert relation.order!("name ASC").equal?(relation)
+      assert_equal ["name ASC"], relation.order_values
     end
 
-    test '#order! with symbol prepends the table name' do
+    test "#order! with symbol prepends the table name" do
       assert relation.order!(:name).equal?(relation)
       node = relation.order_values.first
       assert node.ascending?
@@ -61,7 +30,7 @@ module ActiveRecord
       assert_equal "posts", node.expr.relation.name
     end
 
-    test '#order! on non-string does not attempt regexp match for references' do
+    test "#order! on non-string does not attempt regexp match for references" do
       obj = Object.new
       assert_not_called(obj, :=~) do
         assert relation.order!(obj)
@@ -69,12 +38,12 @@ module ActiveRecord
       end
     end
 
-    test '#references!' do
+    test "#references!" do
       assert relation.references!(:foo).equal?(relation)
-      assert relation.references_values.include?('foo')
+      assert_includes relation.references_values, "foo"
     end
 
-    test 'extending!' do
+    test "extending!" do
       mod, mod2 = Module.new, Module.new
 
       assert relation.extending!(mod).equal?(relation)
@@ -85,37 +54,37 @@ module ActiveRecord
       assert_equal [mod, mod2], relation.extending_values
     end
 
-    test 'extending! with empty args' do
+    test "extending! with empty args" do
       relation.extending!
       assert_equal [], relation.extending_values
     end
 
-    (Relation::SINGLE_VALUE_METHODS - [:lock, :reordering, :reverse_order, :create_with, :uniq]).each do |method|
+    (Relation::SINGLE_VALUE_METHODS - [:lock, :reordering, :reverse_order, :create_with, :skip_query_cache]).each do |method|
       test "##{method}!" do
         assert relation.public_send("#{method}!", :foo).equal?(relation)
         assert_equal :foo, relation.public_send("#{method}_value")
       end
     end
 
-    test '#from!' do
-      assert relation.from!('foo').equal?(relation)
-      assert_equal 'foo', relation.from_clause.value
+    test "#from!" do
+      assert relation.from!("foo").equal?(relation)
+      assert_equal "foo", relation.from_clause.value
     end
 
-    test '#lock!' do
-      assert relation.lock!('foo').equal?(relation)
-      assert_equal 'foo', relation.lock_value
+    test "#lock!" do
+      assert relation.lock!("foo").equal?(relation)
+      assert_equal "foo", relation.lock_value
     end
 
-    test '#reorder!' do
-      @relation = self.relation.order('foo')
+    test "#reorder!" do
+      @relation = relation.order("foo")
 
-      assert relation.reorder!('bar').equal?(relation)
-      assert_equal ['bar'], relation.order_values
+      assert relation.reorder!("bar").equal?(relation)
+      assert_equal ["bar"], relation.order_values
       assert relation.reordering_value
     end
 
-    test '#reorder! with symbol prepends the table name' do
+    test "#reorder! with symbol prepends the table name" do
       assert relation.reorder!(:name).equal?(relation)
       node = relation.order_values.first
 
@@ -124,60 +93,53 @@ module ActiveRecord
       assert_equal "posts", node.expr.relation.name
     end
 
-    test 'reverse_order!' do
-      @relation = Post.order('title ASC, comments_count DESC')
+    test "reverse_order!" do
+      @relation = Post.order("title ASC, comments_count DESC")
 
       relation.reverse_order!
 
-      assert_equal 'title DESC', relation.order_values.first
-      assert_equal 'comments_count ASC', relation.order_values.last
-
+      assert_equal "title DESC", relation.order_values.first
+      assert_equal "comments_count ASC", relation.order_values.last
 
       relation.reverse_order!
 
-      assert_equal 'title ASC', relation.order_values.first
-      assert_equal 'comments_count DESC', relation.order_values.last
+      assert_equal "title ASC", relation.order_values.first
+      assert_equal "comments_count DESC", relation.order_values.last
     end
 
-    test 'create_with!' do
-      assert relation.create_with!(foo: 'bar').equal?(relation)
-      assert_equal({foo: 'bar'}, relation.create_with_value)
+    test "create_with!" do
+      assert relation.create_with!(foo: "bar").equal?(relation)
+      assert_equal({ foo: "bar" }, relation.create_with_value)
     end
 
-    test 'test_merge!' do
+    test "merge!" do
       assert relation.merge!(select: :foo).equal?(relation)
       assert_equal [:foo], relation.select_values
     end
 
-    test 'merge with a proc' do
+    test "merge with a proc" do
       assert_equal [:foo], relation.merge(-> { select(:foo) }).select_values
     end
 
-    test 'none!' do
+    test "none!" do
       assert relation.none!.equal?(relation)
       assert_equal [NullRelation], relation.extending_values
       assert relation.is_a?(NullRelation)
     end
 
-    test 'distinct!' do
+    test "distinct!" do
       relation.distinct! :foo
       assert_equal :foo, relation.distinct_value
-
-      assert_deprecated do
-        assert_equal :foo, relation.uniq_value # deprecated access
-      end
     end
 
-    test 'uniq! was replaced by distinct!' do
-      assert_deprecated(/use distinct! instead/) do
-        relation.uniq! :foo
-      end
+    test "skip_query_cache!" do
+      relation.skip_query_cache!
+      assert relation.skip_query_cache_value
+    end
 
-      assert_deprecated(/use distinct_value instead/) do
-        assert_equal :foo, relation.uniq_value # deprecated access
+    private
+      def relation
+        @relation ||= Relation.new(FakeKlass, Post.arel_table, Post.predicate_builder)
       end
-
-      assert_equal :foo, relation.distinct_value
-    end
   end
 end
diff --git a/activerecord/test/cases/relation/or_test.rb b/activerecord/test/cases/relation/or_test.rb
index ce8c5ca489..7e418f9c7d 100644
--- a/activerecord/test/cases/relation/or_test.rb
+++ b/activerecord/test/cases/relation/or_test.rb
@@ -1,32 +1,37 @@
+# frozen_string_literal: true
+
 require "cases/helper"
-require 'models/post'
+require "models/author"
+require "models/categorization"
+require "models/post"
 
 module ActiveRecord
   class OrTest < ActiveRecord::TestCase
     fixtures :posts
+    fixtures :authors, :author_addresses
 
     def test_or_with_relation
-      expected = Post.where('id = 1 or id = 2').to_a
-      assert_equal expected, Post.where('id = 1').or(Post.where('id = 2')).to_a
+      expected = Post.where("id = 1 or id = 2").to_a
+      assert_equal expected, Post.where("id = 1").or(Post.where("id = 2")).to_a
     end
 
     def test_or_identity
-      expected = Post.where('id = 1').to_a
-      assert_equal expected, Post.where('id = 1').or(Post.where('id = 1')).to_a
+      expected = Post.where("id = 1").to_a
+      assert_equal expected, Post.where("id = 1").or(Post.where("id = 1")).to_a
     end
 
     def test_or_with_null_left
-      expected = Post.where('id = 1').to_a
-      assert_equal expected, Post.none.or(Post.where('id = 1')).to_a
+      expected = Post.where("id = 1").to_a
+      assert_equal expected, Post.none.or(Post.where("id = 1")).to_a
     end
 
     def test_or_with_null_right
-      expected = Post.where('id = 1').to_a
-      assert_equal expected, Post.where('id = 1').or(Post.none).to_a
+      expected = Post.where("id = 1").to_a
+      assert_equal expected, Post.where("id = 1").or(Post.none).to_a
     end
 
     def test_or_with_bind_params
-      assert_equal Post.find([1, 2]), Post.where(id: 1).or(Post.where(id: 2)).to_a
+      assert_equal Post.find([1, 2]).sort_by(&:id), Post.where(id: 1).or(Post.where(id: 2)).sort_by(&:id)
     end
 
     def test_or_with_null_both
@@ -36,57 +41,90 @@ module ActiveRecord
 
     def test_or_without_left_where
       expected = Post.all
-      assert_equal expected, Post.or(Post.where('id = 1')).to_a
+      assert_equal expected, Post.or(Post.where("id = 1")).to_a
     end
 
     def test_or_without_right_where
       expected = Post.all
-      assert_equal expected, Post.where('id = 1').or(Post.all).to_a
+      assert_equal expected, Post.where("id = 1").or(Post.all).to_a
     end
 
     def test_or_preserves_other_querying_methods
-      expected = Post.where('id = 1 or id = 2 or id = 3').order('body asc').to_a
-      partial = Post.order('body asc')
-      assert_equal expected, partial.where('id = 1').or(partial.where(:id => [2, 3])).to_a
-      assert_equal expected, Post.order('body asc').where('id = 1').or(Post.order('body asc').where(:id => [2, 3])).to_a
+      expected = Post.where("id = 1 or id = 2 or id = 3").order("body asc").to_a
+      partial = Post.order("body asc")
+      assert_equal expected, partial.where("id = 1").or(partial.where(id: [2, 3])).to_a
+      assert_equal expected, Post.order("body asc").where("id = 1").or(Post.order("body asc").where(id: [2, 3])).to_a
     end
 
     def test_or_with_incompatible_relations
       error = assert_raises ArgumentError do
-        Post.order('body asc').where('id = 1').or(Post.order('id desc').where(:id => [2, 3])).to_a
+        Post.order("body asc").where("id = 1").or(Post.order("id desc").where(id: [2, 3])).to_a
+      end
+
+      assert_equal "Relation passed to #or must be structurally compatible. Incompatible values: [:order]", error.message
+    end
+
+    def test_or_with_unscope_where
+      expected = Post.where("id = 1 or id = 2")
+      partial = Post.where("id = 1 and id != 2")
+      assert_equal expected, partial.or(partial.unscope(:where).where("id = 2")).to_a
+    end
+
+    def test_or_with_unscope_where_column
+      expected = Post.where("id = 1 or id = 2")
+      partial = Post.where(id: 1).where.not(id: 2)
+      assert_equal expected, partial.or(partial.unscope(where: :id).where("id = 2")).to_a
+    end
+
+    def test_or_with_unscope_order
+      expected = Post.where("id = 1 or id = 2")
+      assert_equal expected, Post.order("body asc").where("id = 1").unscope(:order).or(Post.where("id = 2")).to_a
+    end
+
+    def test_or_with_incompatible_unscope
+      error = assert_raises ArgumentError do
+        Post.order("body asc").where("id = 1").or(Post.order("body asc").where("id = 2").unscope(:order)).to_a
       end
 
       assert_equal "Relation passed to #or must be structurally compatible. Incompatible values: [:order]", error.message
     end
 
     def test_or_when_grouping
-      groups = Post.where('id < 10').group('body').select('body, COUNT(*) AS c')
-      expected = groups.having("COUNT(*) > 1 OR body like 'Such%'").to_a.map {|o| [o.body, o.c] }
-      assert_equal expected, groups.having('COUNT(*) > 1').or(groups.having("body like 'Such%'")).to_a.map {|o| [o.body, o.c] }
+      groups = Post.where("id < 10").group("body").select("body, COUNT(*) AS c")
+      expected = groups.having("COUNT(*) > 1 OR body like 'Such%'").to_a.map { |o| [o.body, o.c] }
+      assert_equal expected, groups.having("COUNT(*) > 1").or(groups.having("body like 'Such%'")).to_a.map { |o| [o.body, o.c] }
     end
 
     def test_or_with_named_scope
       expected = Post.where("id = 1 or body LIKE '\%a\%'").to_a
-      assert_equal expected, Post.where('id = 1').or(Post.containing_the_letter_a)
+      assert_equal expected, Post.where("id = 1").or(Post.containing_the_letter_a)
     end
 
     def test_or_inside_named_scope
-      expected = Post.where("body LIKE '\%a\%' OR title LIKE ?", "%'%").order('id DESC').to_a
+      expected = Post.where("body LIKE '\%a\%' OR title LIKE ?", "%'%").order("id DESC").to_a
       assert_equal expected, Post.order(id: :desc).typographically_interesting
     end
 
     def test_or_on_loaded_relation
-      expected = Post.where('id = 1 or id = 2').to_a
-      p = Post.where('id = 1')
+      expected = Post.where("id = 1 or id = 2").to_a
+      p = Post.where("id = 1")
       p.load
-      assert_equal p.loaded?, true
-      assert_equal expected, p.or(Post.where('id = 2')).to_a
+      assert_equal true, p.loaded?
+      assert_equal expected, p.or(Post.where("id = 2")).to_a
     end
 
     def test_or_with_non_relation_object_raises_error
       assert_raises ArgumentError do
-        Post.where(id: [1, 2, 3]).or(title: 'Rails')
+        Post.where(id: [1, 2, 3]).or(title: "Rails")
       end
     end
+
+    def test_or_with_references_inequality
+      joined = Post.includes(:author)
+      actual = joined.where(authors: { id: 1 })
+        .or(joined.where(title: "I don't have any comments"))
+      expected = Author.find(1).posts + Post.where(title: "I don't have any comments")
+      assert_equal expected.sort_by(&:id), actual.sort_by(&:id)
+    end
   end
 end
diff --git a/activerecord/test/cases/relation/predicate_builder_test.rb b/activerecord/test/cases/relation/predicate_builder_test.rb
index 8f62014622..b432330deb 100644
--- a/activerecord/test/cases/relation/predicate_builder_test.rb
+++ b/activerecord/test/cases/relation/predicate_builder_test.rb
@@ -1,11 +1,13 @@
+# frozen_string_literal: true
+
 require "cases/helper"
-require 'models/topic'
+require "models/topic"
 
 module ActiveRecord
   class PredicateBuilderTest < ActiveRecord::TestCase
     def test_registering_new_handlers
       Topic.predicate_builder.register_handler(Regexp, proc do |column, value|
-        Arel::Nodes::InfixOperation.new('~', column, Arel.sql(value.source))
+        Arel::Nodes::InfixOperation.new("~", column, Arel.sql(value.source))
       end)
 
       assert_match %r{["`]topics["`]\.["`]title["`] ~ rails}i, Topic.where(title: /rails/).to_sql
diff --git a/activerecord/test/cases/relation/record_fetch_warning_test.rb b/activerecord/test/cases/relation/record_fetch_warning_test.rb
index 0e0e23b24b..22d32d75bc 100644
--- a/activerecord/test/cases/relation/record_fetch_warning_test.rb
+++ b/activerecord/test/cases/relation/record_fetch_warning_test.rb
@@ -1,6 +1,8 @@
-require 'cases/helper'
-require 'models/post'
-require 'active_record/relation/record_fetch_warning'
+# frozen_string_literal: true
+
+require "cases/helper"
+require "models/post"
+require "active_record/relation/record_fetch_warning"
 
 module ActiveRecord
   class RecordFetchWarningTest < ActiveRecord::TestCase
diff --git a/activerecord/test/cases/relation/where_chain_test.rb b/activerecord/test/cases/relation/where_chain_test.rb
index 27bbd80f79..a68eb2b446 100644
--- a/activerecord/test/cases/relation/where_chain_test.rb
+++ b/activerecord/test/cases/relation/where_chain_test.rb
@@ -1,6 +1,8 @@
-require 'cases/helper'
-require 'models/post'
-require 'models/comment'
+# frozen_string_literal: true
+
+require "cases/helper"
+require "models/post"
+require "models/comment"
 
 module ActiveRecord
   class WhereChainTest < ActiveRecord::TestCase
@@ -8,12 +10,12 @@ module ActiveRecord
 
     def setup
       super
-      @name = 'title'
+      @name = "title"
     end
 
     def test_not_inverts_where_clause
-      relation = Post.where.not(title: 'hello')
-      expected_where_clause = Post.where(title: 'hello').where_clause.invert
+      relation = Post.where.not(title: "hello")
+      expected_where_clause = Post.where(title: "hello").where_clause.invert
 
       assert_equal expected_where_clause, relation.where_clause
     end
@@ -25,55 +27,55 @@ module ActiveRecord
     end
 
     def test_association_not_eq
-      expected = Arel::Nodes::Grouping.new(Comment.arel_table[@name].not_eq(Arel::Nodes::BindParam.new))
-      relation = Post.joins(:comments).where.not(comments: {title: 'hello'})
+      expected = Comment.arel_table[@name].not_eq(Arel::Nodes::BindParam.new(1))
+      relation = Post.joins(:comments).where.not(comments: { title: "hello" })
       assert_equal(expected.to_sql, relation.where_clause.ast.to_sql)
     end
 
     def test_not_eq_with_preceding_where
-      relation = Post.where(title: 'hello').where.not(title: 'world')
+      relation = Post.where(title: "hello").where.not(title: "world")
       expected_where_clause =
-        Post.where(title: 'hello').where_clause +
-        Post.where(title: 'world').where_clause.invert
+        Post.where(title: "hello").where_clause +
+        Post.where(title: "world").where_clause.invert
 
       assert_equal expected_where_clause, relation.where_clause
     end
 
     def test_not_eq_with_succeeding_where
-      relation = Post.where.not(title: 'hello').where(title: 'world')
+      relation = Post.where.not(title: "hello").where(title: "world")
       expected_where_clause =
-        Post.where(title: 'hello').where_clause.invert +
-        Post.where(title: 'world').where_clause
+        Post.where(title: "hello").where_clause.invert +
+        Post.where(title: "world").where_clause
 
       assert_equal expected_where_clause, relation.where_clause
     end
 
     def test_chaining_multiple
-      relation = Post.where.not(author_id: [1, 2]).where.not(title: 'ruby on rails')
+      relation = Post.where.not(author_id: [1, 2]).where.not(title: "ruby on rails")
       expected_where_clause =
         Post.where(author_id: [1, 2]).where_clause.invert +
-        Post.where(title: 'ruby on rails').where_clause.invert
+        Post.where(title: "ruby on rails").where_clause.invert
 
       assert_equal expected_where_clause, relation.where_clause
     end
 
     def test_rewhere_with_one_condition
-      relation = Post.where(title: 'hello').where(title: 'world').rewhere(title: 'alone')
-      expected = Post.where(title: 'alone')
+      relation = Post.where(title: "hello").where(title: "world").rewhere(title: "alone")
+      expected = Post.where(title: "alone")
 
       assert_equal expected.where_clause, relation.where_clause
     end
 
     def test_rewhere_with_multiple_overwriting_conditions
-      relation = Post.where(title: 'hello').where(body: 'world').rewhere(title: 'alone', body: 'again')
-      expected = Post.where(title: 'alone', body: 'again')
+      relation = Post.where(title: "hello").where(body: "world").rewhere(title: "alone", body: "again")
+      expected = Post.where(title: "alone", body: "again")
 
       assert_equal expected.where_clause, relation.where_clause
     end
 
     def test_rewhere_with_one_overwriting_condition_and_one_unrelated
-      relation = Post.where(title: 'hello').where(body: 'world').rewhere(title: 'alone')
-      expected = Post.where(body: 'world', title: 'alone')
+      relation = Post.where(title: "hello").where(body: "world").rewhere(title: "alone")
+      expected = Post.where(body: "world", title: "alone")
 
       assert_equal expected.where_clause, relation.where_clause
     end
diff --git a/activerecord/test/cases/relation/where_clause_test.rb b/activerecord/test/cases/relation/where_clause_test.rb
index c20ed94d90..e5eb159d36 100644
--- a/activerecord/test/cases/relation/where_clause_test.rb
+++ b/activerecord/test/cases/relation/where_clause_test.rb
@@ -1,78 +1,86 @@
+# frozen_string_literal: true
+
 require "cases/helper"
 
 class ActiveRecord::Relation
   class WhereClauseTest < ActiveRecord::TestCase
     test "+ combines two where clauses" do
-      first_clause = WhereClause.new([table["id"].eq(bind_param)], [["id", 1]])
-      second_clause = WhereClause.new([table["name"].eq(bind_param)], [["name", "Sean"]])
+      first_clause = WhereClause.new([table["id"].eq(bind_param(1))])
+      second_clause = WhereClause.new([table["name"].eq(bind_param("Sean"))])
       combined = WhereClause.new(
-        [table["id"].eq(bind_param), table["name"].eq(bind_param)],
-        [["id", 1], ["name", "Sean"]],
+        [table["id"].eq(bind_param(1)), table["name"].eq(bind_param("Sean"))],
       )
 
       assert_equal combined, first_clause + second_clause
     end
 
     test "+ is associative, but not commutative" do
-      a = WhereClause.new(["a"], ["bind a"])
-      b = WhereClause.new(["b"], ["bind b"])
-      c = WhereClause.new(["c"], ["bind c"])
+      a = WhereClause.new(["a"])
+      b = WhereClause.new(["b"])
+      c = WhereClause.new(["c"])
 
       assert_equal a + (b + c), (a + b) + c
       assert_not_equal a + b, b + a
     end
 
     test "an empty where clause is the identity value for +" do
-      clause = WhereClause.new([table["id"].eq(bind_param)], [["id", 1]])
+      clause = WhereClause.new([table["id"].eq(bind_param(1))])
 
       assert_equal clause, clause + WhereClause.empty
     end
 
     test "merge combines two where clauses" do
-      a = WhereClause.new([table["id"].eq(1)], [])
-      b = WhereClause.new([table["name"].eq("Sean")], [])
-      expected = WhereClause.new([table["id"].eq(1), table["name"].eq("Sean")], [])
+      a = WhereClause.new([table["id"].eq(1)])
+      b = WhereClause.new([table["name"].eq("Sean")])
+      expected = WhereClause.new([table["id"].eq(1), table["name"].eq("Sean")])
 
       assert_equal expected, a.merge(b)
     end
 
     test "merge keeps the right side, when two equality clauses reference the same column" do
-      a = WhereClause.new([table["id"].eq(1), table["name"].eq("Sean")], [])
-      b = WhereClause.new([table["name"].eq("Jim")], [])
-      expected = WhereClause.new([table["id"].eq(1), table["name"].eq("Jim")], [])
+      a = WhereClause.new([table["id"].eq(1), table["name"].eq("Sean")])
+      b = WhereClause.new([table["name"].eq("Jim")])
+      expected = WhereClause.new([table["id"].eq(1), table["name"].eq("Jim")])
 
       assert_equal expected, a.merge(b)
     end
 
     test "merge removes bind parameters matching overlapping equality clauses" do
       a = WhereClause.new(
-        [table["id"].eq(bind_param), table["name"].eq(bind_param)],
-        [attribute("id", 1), attribute("name", "Sean")],
+        [table["id"].eq(bind_param(1)), table["name"].eq(bind_param("Sean"))],
       )
       b = WhereClause.new(
-        [table["name"].eq(bind_param)],
-        [attribute("name", "Jim")]
+        [table["name"].eq(bind_param("Jim"))],
       )
       expected = WhereClause.new(
-        [table["id"].eq(bind_param), table["name"].eq(bind_param)],
-        [attribute("id", 1), attribute("name", "Jim")],
+        [table["id"].eq(bind_param(1)), table["name"].eq(bind_param("Jim"))],
       )
 
       assert_equal expected, a.merge(b)
     end
 
     test "merge allows for columns with the same name from different tables" do
-      skip "This is not possible as of 4.2, and the binds do not yet contain sufficient information for this to happen"
-      # We might be able to change the implementation to remove conflicts by index, rather than column name
+      table2 = Arel::Table.new("table2")
+      a = WhereClause.new(
+        [table["id"].eq(bind_param(1)), table2["id"].eq(bind_param(2))],
+      )
+      b = WhereClause.new(
+        [table["id"].eq(bind_param(3))],
+      )
+      expected = WhereClause.new(
+        [table2["id"].eq(bind_param(2)), table["id"].eq(bind_param(3))],
+      )
+
+      assert_equal expected, a.merge(b)
     end
 
     test "a clause knows if it is empty" do
       assert WhereClause.empty.empty?
-      assert_not WhereClause.new(["anything"], []).empty?
+      assert_not WhereClause.new(["anything"]).empty?
     end
 
     test "invert cannot handle nil" do
-      where_clause = WhereClause.new([nil], [])
+      where_clause = WhereClause.new([nil])
 
       assert_raises ArgumentError do
         where_clause.invert
@@ -86,37 +94,47 @@ class ActiveRecord::Relation
         table["id"].eq(1),
         "sql literal",
         random_object
-      ], [])
+      ])
       expected = WhereClause.new([
         table["id"].not_in([1, 2, 3]),
         table["id"].not_eq(1),
         Arel::Nodes::Not.new(Arel::Nodes::SqlLiteral.new("sql literal")),
         Arel::Nodes::Not.new(random_object)
-      ], [])
+      ])
 
       assert_equal expected, original.invert
     end
 
-    test "accept removes binary predicates referencing a given column" do
+    test "except removes binary predicates referencing a given column" do
       where_clause = WhereClause.new([
         table["id"].in([1, 2, 3]),
-        table["name"].eq(bind_param),
-        table["age"].gteq(bind_param),
-      ], [
-        attribute("name", "Sean"),
-        attribute("age", 30),
+        table["name"].eq(bind_param("Sean")),
+        table["age"].gteq(bind_param(30)),
       ])
-      expected = WhereClause.new([table["age"].gteq(bind_param)], [attribute("age", 30)])
+      expected = WhereClause.new([table["age"].gteq(bind_param(30))])
 
       assert_equal expected, where_clause.except("id", "name")
     end
 
+    test "except jumps over unhandled binds (like with OR) correctly" do
+      wcs = (0..9).map do |i|
+        WhereClause.new([table["id#{i}"].eq(bind_param(i))])
+      end
+
+      wc = wcs[0] + wcs[1] + wcs[2].or(wcs[3]) + wcs[4] + wcs[5] + wcs[6].or(wcs[7]) + wcs[8] + wcs[9]
+
+      expected = wcs[0] + wcs[2].or(wcs[3]) + wcs[5] + wcs[6].or(wcs[7]) + wcs[9]
+      actual = wc.except("id1", "id2", "id4", "id7", "id8")
+
+      assert_equal expected, actual
+    end
+
     test "ast groups its predicates with AND" do
       predicates = [
         table["id"].in([1, 2, 3]),
-        table["name"].eq(bind_param),
+        table["name"].eq(bind_param(nil)),
       ]
-      where_clause = WhereClause.new(predicates, [])
+      where_clause = WhereClause.new(predicates)
       expected = Arel::Nodes::And.new(predicates)
 
       assert_equal expected, where_clause.ast
@@ -128,55 +146,96 @@ class ActiveRecord::Relation
         table["id"].in([1, 2, 3]),
         "foo = bar",
         random_object,
-      ], [])
+      ])
       expected = Arel::Nodes::And.new([
         table["id"].in([1, 2, 3]),
         Arel::Nodes::Grouping.new(Arel.sql("foo = bar")),
-        Arel::Nodes::Grouping.new(random_object),
+        random_object,
       ])
 
       assert_equal expected, where_clause.ast
     end
 
     test "ast removes any empty strings" do
-      where_clause = WhereClause.new([table["id"].in([1, 2, 3])], [])
-      where_clause_with_empty = WhereClause.new([table["id"].in([1, 2, 3]), ''], [])
+      where_clause = WhereClause.new([table["id"].in([1, 2, 3])])
+      where_clause_with_empty = WhereClause.new([table["id"].in([1, 2, 3]), ""])
 
       assert_equal where_clause.ast, where_clause_with_empty.ast
     end
 
     test "or joins the two clauses using OR" do
-      where_clause = WhereClause.new([table["id"].eq(bind_param)], [attribute("id", 1)])
-      other_clause = WhereClause.new([table["name"].eq(bind_param)], [attribute("name", "Sean")])
+      where_clause = WhereClause.new([table["id"].eq(bind_param(1))])
+      other_clause = WhereClause.new([table["name"].eq(bind_param("Sean"))])
       expected_ast =
         Arel::Nodes::Grouping.new(
-          Arel::Nodes::Or.new(table["id"].eq(bind_param), table["name"].eq(bind_param))
+          Arel::Nodes::Or.new(table["id"].eq(bind_param(1)), table["name"].eq(bind_param("Sean")))
         )
-      expected_binds = where_clause.binds + other_clause.binds
 
       assert_equal expected_ast.to_sql, where_clause.or(other_clause).ast.to_sql
-      assert_equal expected_binds, where_clause.or(other_clause).binds
     end
 
     test "or returns an empty where clause when either side is empty" do
-      where_clause = WhereClause.new([table["id"].eq(bind_param)], [attribute("id", 1)])
+      where_clause = WhereClause.new([table["id"].eq(bind_param(1))])
 
       assert_equal WhereClause.empty, where_clause.or(WhereClause.empty)
       assert_equal WhereClause.empty, WhereClause.empty.or(where_clause)
     end
 
-    private
+    test "or places common conditions before the OR" do
+      a = WhereClause.new(
+        [table["id"].eq(bind_param(1)), table["name"].eq(bind_param("Sean"))],
+      )
+      b = WhereClause.new(
+        [table["id"].eq(bind_param(1)), table["hair_color"].eq(bind_param("black"))],
+      )
+
+      common = WhereClause.new(
+        [table["id"].eq(bind_param(1))],
+      )
+
+      or_clause = WhereClause.new([table["name"].eq(bind_param("Sean"))])
+        .or(WhereClause.new([table["hair_color"].eq(bind_param("black"))]))
 
-    def table
-      Arel::Table.new("table")
+      assert_equal common + or_clause, a.or(b)
     end
 
-    def bind_param
-      Arel::Nodes::BindParam.new
+    test "or can detect identical or as being a common condition" do
+      common_or = WhereClause.new([table["name"].eq(bind_param("Sean"))])
+        .or(WhereClause.new([table["hair_color"].eq(bind_param("black"))]))
+
+      a = common_or + WhereClause.new([table["id"].eq(bind_param(1))])
+      b = common_or + WhereClause.new([table["foo"].eq(bind_param("bar"))])
+
+      new_or = WhereClause.new([table["id"].eq(bind_param(1))])
+        .or(WhereClause.new([table["foo"].eq(bind_param("bar"))]))
+
+      assert_equal common_or + new_or, a.or(b)
     end
 
-    def attribute(name, value)
-      ActiveRecord::Attribute.with_cast_value(name, value, ActiveRecord::Type::Value.new)
+    test "or will use only common conditions if one side only has common conditions" do
+      only_common = WhereClause.new([
+        table["id"].eq(bind_param(1)),
+        "foo = bar",
+      ])
+
+      common_with_extra = WhereClause.new([
+        table["id"].eq(bind_param(1)),
+        "foo = bar",
+        table["extra"].eq(bind_param("pluto")),
+      ])
+
+      assert_equal only_common, only_common.or(common_with_extra)
+      assert_equal only_common, common_with_extra.or(only_common)
     end
+
+    private
+
+      def table
+        Arel::Table.new("table")
+      end
+
+      def bind_param(value)
+        Arel::Nodes::BindParam.new(value)
+      end
   end
 end
diff --git a/activerecord/test/cases/relation/where_test.rb b/activerecord/test/cases/relation/where_test.rb
index 56a2b5b8c6..99797528b2 100644
--- a/activerecord/test/cases/relation/where_test.rb
+++ b/activerecord/test/cases/relation/where_test.rb
@@ -1,13 +1,15 @@
+# frozen_string_literal: true
+
 require "cases/helper"
 require "models/author"
 require "models/binary"
 require "models/cake_designer"
 require "models/car"
 require "models/chef"
+require "models/post"
 require "models/comment"
 require "models/edge"
 require "models/essay"
-require "models/post"
 require "models/price_estimate"
 require "models/topic"
 require "models/treasure"
@@ -15,11 +17,11 @@ require "models/vertex"
 
 module ActiveRecord
   class WhereTest < ActiveRecord::TestCase
-    fixtures :posts, :edges, :authors, :binaries, :essays, :cars, :treasures, :price_estimates
+    fixtures :posts, :edges, :authors, :author_addresses, :binaries, :essays, :cars, :treasures, :price_estimates, :topics
 
     def test_where_copies_bind_params
       author = authors(:david)
-      posts  = author.posts.where('posts.id != 1')
+      posts  = author.posts.where("posts.id != 1")
       joined = Post.where(id: posts)
 
       assert_operator joined.length, :>, 0
@@ -48,8 +50,12 @@ module ActiveRecord
       assert_equal [chef], chefs.to_a
     end
 
+    def test_where_with_casted_value_is_nil
+      assert_equal 4, Topic.where(last_read: "").count
+    end
+
     def test_rewhere_on_root
-      assert_equal posts(:welcome), Post.rewhere(title: 'Welcome to the weblog').first
+      assert_equal posts(:welcome), Post.rewhere(title: "Welcome to the weblog").first
     end
 
     def test_belongs_to_shallow_where
@@ -64,12 +70,12 @@ module ActiveRecord
     end
 
     def test_belongs_to_array_value_where
-      assert_equal Post.where(author_id: [1,2]).to_sql, Post.where(author: [1,2]).to_sql
+      assert_equal Post.where(author_id: [1, 2]).to_sql, Post.where(author: [1, 2]).to_sql
     end
 
     def test_belongs_to_nested_relation_where
-      expected = Post.where(author_id: Author.where(id: [1,2])).to_sql
-      actual   = Post.where(author:    Author.where(id: [1,2])).to_sql
+      expected = Post.where(author_id: Author.where(id: [1, 2])).to_sql
+      actual   = Post.where(author:    Author.where(id: [1, 2])).to_sql
 
       assert_equal expected, actual
     end
@@ -87,7 +93,7 @@ module ActiveRecord
     def test_belongs_to_nested_where_with_relation
       author = authors(:david)
 
-      expected = Author.where(id: author ).joins(:posts)
+      expected = Author.where(id: author).joins(:posts)
       actual   = Author.where(posts: { author_id: Author.where(id: author.id) }).joins(:posts)
 
       assert_equal expected.to_a, actual.to_a
@@ -97,38 +103,57 @@ module ActiveRecord
       treasure = Treasure.new
       treasure.id = 1
 
-      expected = PriceEstimate.where(estimate_of_type: 'Treasure', estimate_of_id: 1)
+      expected = PriceEstimate.where(estimate_of_type: "Treasure", estimate_of_id: 1)
       actual   = PriceEstimate.where(estimate_of: treasure)
 
       assert_equal expected.to_sql, actual.to_sql
     end
 
+    def test_polymorphic_shallow_where_not
+      treasure = treasures(:sapphire)
+
+      expected = [price_estimates(:diamond), price_estimates(:honda)]
+      actual   = PriceEstimate.where.not(estimate_of: treasure)
+
+      assert_equal expected.sort_by(&:id), actual.sort_by(&:id)
+    end
+
     def test_polymorphic_nested_array_where
       treasure = Treasure.new
       treasure.id = 1
       hidden = HiddenTreasure.new
       hidden.id = 2
 
-      expected = PriceEstimate.where(estimate_of_type: 'Treasure', estimate_of_id: [treasure, hidden])
+      expected = PriceEstimate.where(estimate_of_type: "Treasure", estimate_of_id: [treasure, hidden])
       actual   = PriceEstimate.where(estimate_of: [treasure, hidden])
 
       assert_equal expected.to_sql, actual.to_sql
     end
 
+    def test_polymorphic_nested_array_where_not
+      treasure = treasures(:diamond)
+      car = cars(:honda)
+
+      expected = [price_estimates(:sapphire_1), price_estimates(:sapphire_2)]
+      actual   = PriceEstimate.where.not(estimate_of: [treasure, car])
+
+      assert_equal expected.sort_by(&:id), actual.sort_by(&:id)
+    end
+
     def test_polymorphic_array_where_multiple_types
       treasure_1 = treasures(:diamond)
       treasure_2 = treasures(:sapphire)
       car = cars(:honda)
 
       expected = [price_estimates(:diamond), price_estimates(:sapphire_1), price_estimates(:sapphire_2), price_estimates(:honda)].sort
-      actual   = PriceEstimate.where(estimate_of: [treasure_1, treasure_2, car]).to_a.sort
+      actual = PriceEstimate.where(estimate_of: [treasure_1, treasure_2, car]).to_a.sort
 
       assert_equal expected, actual
     end
 
     def test_polymorphic_nested_relation_where
-      expected = PriceEstimate.where(estimate_of_type: 'Treasure', estimate_of_id: Treasure.where(id: [1,2]))
-      actual   = PriceEstimate.where(estimate_of: Treasure.where(id: [1,2]))
+      expected = PriceEstimate.where(estimate_of_type: "Treasure", estimate_of_id: Treasure.where(id: [1, 2]))
+      actual   = PriceEstimate.where(estimate_of: Treasure.where(id: [1, 2]))
 
       assert_equal expected.to_sql, actual.to_sql
     end
@@ -137,7 +162,7 @@ module ActiveRecord
       treasure = HiddenTreasure.new
       treasure.id = 1
 
-      expected = PriceEstimate.where(estimate_of_type: 'Treasure', estimate_of_id: 1)
+      expected = PriceEstimate.where(estimate_of_type: "Treasure", estimate_of_id: 1)
       actual   = PriceEstimate.where(estimate_of: treasure)
 
       assert_equal expected.to_sql, actual.to_sql
@@ -147,7 +172,7 @@ module ActiveRecord
       thing = Post.new
       thing.id = 1
 
-      expected = Treasure.where(price_estimates: { thing_type: 'Post', thing_id: 1 }).joins(:price_estimates)
+      expected = Treasure.where(price_estimates: { thing_type: "Post", thing_id: 1 }).joins(:price_estimates)
       actual   = Treasure.where(price_estimates: { thing: thing }).joins(:price_estimates)
 
       assert_equal expected.to_sql, actual.to_sql
@@ -157,7 +182,7 @@ module ActiveRecord
       treasure = HiddenTreasure.new
       treasure.id = 1
 
-      expected = Treasure.where(price_estimates: { estimate_of_type: 'Treasure', estimate_of_id: 1 }).joins(:price_estimates)
+      expected = Treasure.where(price_estimates: { estimate_of_type: "Treasure", estimate_of_id: 1 }).joins(:price_estimates)
       actual   = Treasure.where(price_estimates: { estimate_of: treasure }).joins(:price_estimates)
 
       assert_equal expected.to_sql, actual.to_sql
@@ -182,40 +207,40 @@ module ActiveRecord
       treasure.id = 1
       decorated_treasure = treasure_decorator.new(treasure)
 
-      expected = PriceEstimate.where(estimate_of_type: 'Treasure', estimate_of_id: 1)
+      expected = PriceEstimate.where(estimate_of_type: "Treasure", estimate_of_id: 1)
       actual   = PriceEstimate.where(estimate_of: decorated_treasure)
 
       assert_equal expected.to_sql, actual.to_sql
     end
 
     def test_aliased_attribute
-      expected = Topic.where(heading: 'The First Topic')
-      actual   = Topic.where(title: 'The First Topic')
+      expected = Topic.where(heading: "The First Topic")
+      actual   = Topic.where(title: "The First Topic")
 
       assert_equal expected.to_sql, actual.to_sql
     end
 
     def test_where_error
-      assert_raises(ActiveRecord::StatementInvalid) do
-        Post.where(:id => { 'posts.author_id' => 10 }).first
+      assert_nothing_raised do
+        Post.where(id: { "posts.author_id" => 10 }).first
       end
     end
 
     def test_where_with_table_name
       post = Post.first
-      assert_equal post, Post.where(:posts => { 'id' => post.id }).first
+      assert_equal post, Post.where(posts: { "id" => post.id }).first
     end
 
     def test_where_with_table_name_and_empty_hash
-      assert_equal 0, Post.where(:posts => {}).count
+      assert_equal 0, Post.where(posts: {}).count
     end
 
     def test_where_with_table_name_and_empty_array
-      assert_equal 0, Post.where(:id => []).count
+      assert_equal 0, Post.where(id: []).count
     end
 
     def test_where_with_empty_hash_and_no_foreign_key
-      assert_equal 0, Edge.where(:sink => {}).count
+      assert_equal 0, Edge.where(sink: {}).count
     end
 
     def test_where_with_blank_conditions
@@ -225,32 +250,32 @@ module ActiveRecord
     end
 
     def test_where_with_integer_for_string_column
-      count = Post.where(:title => 0).count
+      count = Post.where(title: 0).count
       assert_equal 0, count
     end
 
     def test_where_with_float_for_string_column
-      count = Post.where(:title => 0.0).count
+      count = Post.where(title: 0.0).count
       assert_equal 0, count
     end
 
     def test_where_with_boolean_for_string_column
-      count = Post.where(:title => false).count
+      count = Post.where(title: false).count
       assert_equal 0, count
     end
 
     def test_where_with_decimal_for_string_column
-      count = Post.where(:title => BigDecimal.new(0)).count
+      count = Post.where(title: BigDecimal(0)).count
       assert_equal 0, count
     end
 
     def test_where_with_duration_for_string_column
-      count = Post.where(:title => 0.seconds).count
+      count = Post.where(title: 0.seconds).count
       assert_equal 0, count
     end
 
     def test_where_with_integer_for_binary_column
-      count = Binary.where(:data => 0).count
+      count = Binary.where(data: 0).count
       assert_equal 0, count
     end
 
@@ -289,6 +314,25 @@ module ActiveRecord
       assert_equal essays(:david_modest_proposal), essay
     end
 
+    def test_where_with_relation_on_has_many_association
+      essay = essays(:david_modest_proposal)
+      author = Author.where(essays: Essay.where(id: essay.id)).first
+
+      assert_equal authors(:david), author
+    end
+
+    def test_where_with_relation_on_has_one_association
+      author = authors(:david)
+      author_address = AuthorAddress.where(author: Author.where(id: author.id)).first
+      assert_equal author_addresses(:david_address), author_address
+    end
+
+
+    def test_where_on_association_with_select_relation
+      essay = Essay.where(author: Author.where(name: "David").select(:name)).take
+      assert_equal essays(:david_modest_proposal), essay
+    end
+
     def test_where_with_strong_parameters
       protected_params = Class.new do
         attr_reader :permitted
diff --git a/activerecord/test/cases/relation_test.rb b/activerecord/test/cases/relation_test.rb
index 03583344a8..b424ca91de 100644
--- a/activerecord/test/cases/relation_test.rb
+++ b/activerecord/test/cases/relation_test.rb
@@ -1,36 +1,20 @@
+# frozen_string_literal: true
+
 require "cases/helper"
-require 'models/post'
-require 'models/comment'
-require 'models/author'
-require 'models/rating'
+require "models/post"
+require "models/comment"
+require "models/author"
+require "models/rating"
 
 module ActiveRecord
   class RelationTest < ActiveRecord::TestCase
-    fixtures :posts, :comments, :authors
-
-    class FakeKlass < Struct.new(:table_name, :name)
-      extend ActiveRecord::Delegation::DelegateCache
-
-      inherited self
-
-      def self.connection
-        Post.connection
-      end
-
-      def self.table_name
-        'fake_table'
-      end
-
-      def self.sanitize_sql_for_order(sql)
-        sql
-      end
-    end
+    fixtures :posts, :comments, :authors, :author_addresses, :ratings
 
     def test_construction
       relation = Relation.new(FakeKlass, :b, nil)
       assert_equal FakeKlass, relation.klass
       assert_equal :b, relation.table
-      assert !relation.loaded, 'relation is not loaded'
+      assert !relation.loaded, "relation is not loaded"
     end
 
     def test_responds_to_model_and_returns_klass
@@ -40,9 +24,10 @@ module ActiveRecord
 
     def test_initialize_single_values
       relation = Relation.new(FakeKlass, :b, nil)
-      (Relation::SINGLE_VALUE_METHODS - [:create_with]).each do |method|
+      (Relation::SINGLE_VALUE_METHODS - [:create_with, :readonly]).each do |method|
         assert_nil relation.send("#{method}_value"), method.to_s
       end
+      assert_equal false, relation.readonly_value
       value = relation.create_with_value
       assert_equal({}, value)
       assert_predicate value, :frozen?
@@ -69,8 +54,8 @@ module ActiveRecord
 
     def test_has_values
       relation = Relation.new(Post, Post.arel_table, Post.predicate_builder)
-      relation.where! relation.table[:id].eq(10)
-      assert_equal({:id => 10}, relation.where_values_hash)
+      relation.where!(id: 10)
+      assert_equal({ "id" => 10 }, relation.where_values_hash)
     end
 
     def test_values_wrong_table
@@ -83,16 +68,11 @@ module ActiveRecord
       relation = Relation.new(Post, Post.arel_table, Post.predicate_builder)
       left     = relation.table[:id].eq(10)
       right    = relation.table[:id].eq(10)
-      combine  = left.and right
+      combine  = left.or(right)
       relation.where! combine
       assert_equal({}, relation.where_values_hash)
     end
 
-    def test_table_name_delegates_to_klass
-      relation = Relation.new(FakeKlass.new('posts'), :b, Post.predicate_builder)
-      assert_equal 'posts', relation.table_name
-    end
-
     def test_scope_for_create
       relation = Relation.new(FakeKlass, :b, nil)
       assert_equal({}, relation.scope_for_create)
@@ -100,28 +80,27 @@ module ActiveRecord
 
     def test_create_with_value
       relation = Relation.new(Post, Post.arel_table, Post.predicate_builder)
-      hash = { :hello => 'world' }
-      relation.create_with_value = hash
-      assert_equal hash, relation.scope_for_create
+      relation.create_with_value = { hello: "world" }
+      assert_equal({ "hello" => "world" }, relation.scope_for_create)
     end
 
     def test_create_with_value_with_wheres
       relation = Relation.new(Post, Post.arel_table, Post.predicate_builder)
-      relation.where! relation.table[:id].eq(10)
-      relation.create_with_value = {:hello => 'world'}
-      assert_equal({:hello => 'world', :id => 10}, relation.scope_for_create)
+      assert_equal({}, relation.scope_for_create)
+
+      relation.where!(id: 10)
+      assert_equal({ "id" => 10 }, relation.scope_for_create)
+
+      relation.create_with_value = { hello: "world" }
+      assert_equal({ "hello" => "world", "id" => 10 }, relation.scope_for_create)
     end
 
-    # FIXME: is this really wanted or expected behavior?
-    def test_scope_for_create_is_cached
+    def test_empty_scope
       relation = Relation.new(Post, Post.arel_table, Post.predicate_builder)
-      assert_equal({}, relation.scope_for_create)
-
-      relation.where! relation.table[:id].eq(10)
-      assert_equal({}, relation.scope_for_create)
+      assert relation.empty_scope?
 
-      relation.create_with_value = {:hello => 'world'}
-      assert_equal({}, relation.scope_for_create)
+      relation.merge!(relation)
+      assert relation.empty_scope?
     end
 
     def test_bad_constants_raise_errors
@@ -145,48 +124,48 @@ module ActiveRecord
       relation = Relation.new(FakeKlass, :b, nil)
       assert_equal [], relation.references_values
       relation = relation.references(:foo).references(:omg, :lol)
-      assert_equal ['foo', 'omg', 'lol'], relation.references_values
+      assert_equal ["foo", "omg", "lol"], relation.references_values
     end
 
     def test_references_values_dont_duplicate
       relation = Relation.new(FakeKlass, :b, nil)
       relation = relation.references(:foo).references(:foo)
-      assert_equal ['foo'], relation.references_values
+      assert_equal ["foo"], relation.references_values
     end
 
-    test 'merging a hash into a relation' do
+    test "merging a hash into a relation" do
       relation = Relation.new(Post, Post.arel_table, Post.predicate_builder)
-      relation = relation.merge where: {name: :lol}, readonly: true
+      relation = relation.merge where: { name: :lol }, readonly: true
 
-      assert_equal({"name"=>:lol}, relation.where_clause.to_h)
+      assert_equal({ "name" => :lol }, relation.where_clause.to_h)
       assert_equal true, relation.readonly_value
     end
 
-    test 'merging an empty hash into a relation' do
+    test "merging an empty hash into a relation" do
       assert_equal Relation::WhereClause.empty, Relation.new(FakeKlass, :b, nil).merge({}).where_clause
     end
 
-    test 'merging a hash with unknown keys raises' do
-      assert_raises(ArgumentError) { Relation::HashMerger.new(nil, omg: 'lol') }
+    test "merging a hash with unknown keys raises" do
+      assert_raises(ArgumentError) { Relation::HashMerger.new(nil, omg: "lol") }
     end
 
-    test 'merging nil or false raises' do
+    test "merging nil or false raises" do
       relation = Relation.new(FakeKlass, :b, nil)
 
       e = assert_raises(ArgumentError) do
         relation = relation.merge nil
       end
 
-      assert_equal 'invalid argument: nil.', e.message
+      assert_equal "invalid argument: nil.", e.message
 
       e = assert_raises(ArgumentError) do
         relation = relation.merge false
       end
 
-      assert_equal 'invalid argument: false.', e.message
+      assert_equal "invalid argument: false.", e.message
     end
 
-    test '#values returns a dup of the values' do
+    test "#values returns a dup of the values" do
       relation = Relation.new(Post, Post.arel_table, Post.predicate_builder).where!(name: :foo)
       values   = relation.values
 
@@ -194,22 +173,22 @@ module ActiveRecord
       assert_not_nil relation.where_clause
     end
 
-    test 'relations can be created with a values hash' do
+    test "relations can be created with a values hash" do
       relation = Relation.new(FakeKlass, :b, nil, select: [:foo])
       assert_equal [:foo], relation.select_values
     end
 
-    test 'merging a hash interpolates conditions' do
+    test "merging a hash interpolates conditions" do
       klass = Class.new(FakeKlass) do
         def self.sanitize_sql(args)
-          raise unless args == ['foo = ?', 'bar']
-          'foo = bar'
+          raise unless args == ["foo = ?", "bar"]
+          "foo = bar"
         end
       end
 
       relation = Relation.new(klass, :b, nil)
-      relation.merge!(where: ['foo = ?', 'bar'])
-      assert_equal Relation::WhereClause.new(['foo = bar'], []), relation.where_clause
+      relation.merge!(where: ["foo = ?", "bar"])
+      assert_equal Relation::WhereClause.new(["foo = bar"]), relation.where_clause
     end
 
     def test_merging_readonly_false
@@ -223,7 +202,26 @@ module ActiveRecord
     def test_relation_merging_with_merged_joins_as_symbols
       special_comments_with_ratings = SpecialComment.joins(:ratings)
       posts_with_special_comments_with_ratings = Post.group("posts.id").joins(:special_comments).merge(special_comments_with_ratings)
-      assert_equal 3, authors(:david).posts.merge(posts_with_special_comments_with_ratings).count.length
+      assert_equal({ 4 => 2 }, authors(:david).posts.merge(posts_with_special_comments_with_ratings).count)
+    end
+
+    def test_relation_merging_with_merged_symbol_joins_keeps_inner_joins
+      queries = capture_sql { Author.joins(:posts).merge(Post.joins(:comments)).to_a }
+
+      nb_inner_join = queries.sum { |sql| sql.scan(/INNER\s+JOIN/i).size }
+      assert_equal 2, nb_inner_join, "Wrong amount of INNER JOIN in query"
+      assert queries.none? { |sql| /LEFT\s+(OUTER)?\s+JOIN/i.match?(sql) }, "Shouldn't have any LEFT JOIN in query"
+    end
+
+    def test_relation_merging_with_merged_symbol_joins_has_correct_size_and_count
+      # Has one entry per comment
+      merged_authors_with_commented_posts_relation = Author.joins(:posts).merge(Post.joins(:comments))
+
+      post_ids_with_author = Post.joins(:author).pluck(:id)
+      manual_comments_on_post_that_have_author = Comment.where(post_id: post_ids_with_author).pluck(:id)
+
+      assert_equal manual_comments_on_post_that_have_author.size, merged_authors_with_commented_posts_relation.count
+      assert_equal manual_comments_on_post_that_have_author.size, merged_authors_with_commented_posts_relation.to_a.size
     end
 
     def test_relation_merging_with_joins_as_join_dependency_pick_proper_parent
@@ -273,7 +271,16 @@ module ActiveRecord
       join_string = "LEFT OUTER JOIN #{Rating.quoted_table_name} ON #{SpecialComment.quoted_table_name}.id = #{Rating.quoted_table_name}.comment_id"
       special_comments_with_ratings = SpecialComment.joins join_string
       posts_with_special_comments_with_ratings = Post.group("posts.id").joins(:special_comments).merge(special_comments_with_ratings)
-      assert_equal 3, authors(:david).posts.merge(posts_with_special_comments_with_ratings).count.length
+      assert_equal({ 2 => 1, 4 => 3, 5 => 1 }, authors(:david).posts.merge(posts_with_special_comments_with_ratings).count)
+    end
+
+    def test_relation_merging_keeps_joining_order
+      authors  = Author.where(id: 1)
+      posts    = Post.joins(:author).merge(authors)
+      comments = Comment.joins(:post).merge(posts)
+      ratings  = Rating.joins(:comment).merge(comments)
+
+      assert_equal 3, ratings.count
     end
 
     class EnsureRoundTripTypeCasting < ActiveRecord::Type::Value
@@ -281,19 +288,24 @@ module ActiveRecord
         :string
       end
 
+      def cast(value)
+        raise value unless value == "value from user"
+        "cast value"
+      end
+
       def deserialize(value)
         raise value unless value == "type cast for database"
         "type cast from database"
       end
 
       def serialize(value)
-        raise value unless value == "value from user"
+        raise value unless value == "cast value"
         "type cast for database"
       end
     end
 
     class UpdateAllTestModel < ActiveRecord::Base
-      self.table_name = 'posts'
+      self.table_name = "posts"
 
       attribute :body, EnsureRoundTripTypeCasting.new
     end
@@ -306,23 +318,23 @@ module ActiveRecord
 
     private
 
-    def skip_if_sqlite3_version_includes_quoting_bug
-      if sqlite3_version_includes_quoting_bug?
-        skip <<-ERROR.squish
-          You are using an outdated version of SQLite3 which has a bug in
-          quoted column names. Please update SQLite3 and rebuild the sqlite3
-          ruby gem
-        ERROR
+      def skip_if_sqlite3_version_includes_quoting_bug
+        if sqlite3_version_includes_quoting_bug?
+          skip <<-ERROR.squish
+            You are using an outdated version of SQLite3 which has a bug in
+            quoted column names. Please update SQLite3 and rebuild the sqlite3
+            ruby gem
+          ERROR
+        end
       end
-    end
 
-    def sqlite3_version_includes_quoting_bug?
-      if current_adapter?(:SQLite3Adapter)
-        selected_quoted_column_names = ActiveRecord::Base.connection.exec_query(
-          'SELECT "join" FROM (SELECT id AS "join" FROM posts) subquery'
-        ).columns
-        ["join"] != selected_quoted_column_names
+      def sqlite3_version_includes_quoting_bug?
+        if current_adapter?(:SQLite3Adapter)
+          selected_quoted_column_names = ActiveRecord::Base.connection.exec_query(
+            'SELECT "join" FROM (SELECT id AS "join" FROM posts) subquery'
+          ).columns
+          ["join"] != selected_quoted_column_names
+        end
       end
-    end
   end
 end
diff --git a/activerecord/test/cases/relations_test.rb b/activerecord/test/cases/relations_test.rb
index 5604124bb3..7785f8c99b 100644
--- a/activerecord/test/cases/relations_test.rb
+++ b/activerecord/test/cases/relations_test.rb
@@ -1,45 +1,46 @@
+# frozen_string_literal: true
+
 require "cases/helper"
-require 'models/tag'
-require 'models/tagging'
-require 'models/post'
-require 'models/topic'
-require 'models/comment'
-require 'models/author'
-require 'models/entrant'
-require 'models/developer'
-require 'models/computer'
-require 'models/reply'
-require 'models/company'
-require 'models/bird'
-require 'models/car'
-require 'models/engine'
-require 'models/tyre'
-require 'models/minivan'
-require 'models/aircraft'
+require "models/tag"
+require "models/tagging"
+require "models/post"
+require "models/topic"
+require "models/comment"
+require "models/author"
+require "models/entrant"
+require "models/developer"
+require "models/computer"
+require "models/reply"
+require "models/company"
+require "models/bird"
+require "models/car"
+require "models/engine"
+require "models/tyre"
+require "models/minivan"
 require "models/possession"
 require "models/reader"
+require "models/category"
 require "models/categorization"
 require "models/edge"
 
 class RelationTest < ActiveRecord::TestCase
-  fixtures :authors, :topics, :entrants, :developers, :companies, :developers_projects, :accounts, :categories, :categorizations, :posts, :comments,
-    :tags, :taggings, :cars, :minivans
+  fixtures :authors, :author_addresses, :topics, :entrants, :developers, :companies, :developers_projects, :accounts, :categories, :categorizations, :categories_posts, :posts, :comments, :tags, :taggings, :cars, :minivans
 
   class TopicWithCallbacks < ActiveRecord::Base
     self.table_name = :topics
-    before_update { |topic| topic.author_name = 'David' if topic.author_name.blank? }
+    before_update { |topic| topic.author_name = "David" if topic.author_name.blank? }
   end
 
   def test_do_not_double_quote_string_id
     van = Minivan.last
     assert van
-    assert_equal van.id, Minivan.where(:minivan_id => van).to_a.first.minivan_id
+    assert_equal van.id, Minivan.where(minivan_id: van).to_a.first.minivan_id
   end
 
   def test_do_not_double_quote_string_id_with_array
     van = Minivan.last
     assert van
-    assert_equal van, Minivan.where(:minivan_id => [van]).to_a.first
+    assert_equal van, Minivan.where(minivan_id: [van]).to_a.first
   end
 
   def test_two_scopes_with_includes_should_not_drop_any_include
@@ -54,12 +55,12 @@ class RelationTest < ActiveRecord::TestCase
   end
 
   def test_dynamic_finder
-    x = Post.where('author_id = ?', 1)
-    assert x.klass.respond_to?(:find_by_id), '@klass should handle dynamic finders'
+    x = Post.where("author_id = ?", 1)
+    assert x.klass.respond_to?(:find_by_id), "@klass should handle dynamic finders"
   end
 
   def test_multivalue_where
-    posts = Post.where('author_id = ? AND id = ?', 1, 1)
+    posts = Post.where("author_id = ? AND id = ?", 1, 1)
     assert_equal 1, posts.to_a.size
   end
 
@@ -101,7 +102,7 @@ class RelationTest < ActiveRecord::TestCase
   end
 
   def test_scoped_first
-    topics = Topic.all.order('id ASC')
+    topics = Topic.all.order("id ASC")
 
     assert_queries(1) do
       2.times { assert_equal "The First Topic", topics.first.title }
@@ -111,8 +112,8 @@ class RelationTest < ActiveRecord::TestCase
   end
 
   def test_loaded_first
-    topics = Topic.all.order('id ASC')
-    topics.to_a # force load
+    topics = Topic.all.order("id ASC")
+    topics.load # force load
 
     assert_no_queries do
       assert_equal "The First Topic", topics.first.title
@@ -122,8 +123,8 @@ class RelationTest < ActiveRecord::TestCase
   end
 
   def test_loaded_first_with_limit
-    topics = Topic.all.order('id ASC')
-    topics.to_a # force load
+    topics = Topic.all.order("id ASC")
+    topics.load # force load
 
     assert_no_queries do
       assert_equal ["The First Topic",
@@ -134,9 +135,9 @@ class RelationTest < ActiveRecord::TestCase
   end
 
   def test_first_get_more_than_available
-    topics = Topic.all.order('id ASC')
+    topics = Topic.all.order("id ASC")
     unloaded_first = topics.first(10)
-    topics.to_a # force load
+    topics.load # force load
 
     assert_no_queries do
       loaded_first = topics.first(10)
@@ -154,7 +155,7 @@ class RelationTest < ActiveRecord::TestCase
     assert topics.loaded?
 
     original_size = topics.to_a.size
-    Topic.create! :title => 'fake'
+    Topic.create! title: "fake"
 
     assert_queries(1) { topics.reload }
     assert_equal original_size + 1, topics.size
@@ -162,17 +163,17 @@ class RelationTest < ActiveRecord::TestCase
   end
 
   def test_finding_with_subquery
-    relation = Topic.where(:approved => true)
-    assert_equal relation.to_a, Topic.select('*').from(relation).to_a
-    assert_equal relation.to_a, Topic.select('subquery.*').from(relation).to_a
-    assert_equal relation.to_a, Topic.select('a.*').from(relation, :a).to_a
+    relation = Topic.where(approved: true)
+    assert_equal relation.to_a, Topic.select("*").from(relation).to_a
+    assert_equal relation.to_a, Topic.select("subquery.*").from(relation).to_a
+    assert_equal relation.to_a, Topic.select("a.*").from(relation, :a).to_a
   end
 
   def test_finding_with_subquery_with_binds
     relation = Post.first.comments
-    assert_equal relation.to_a, Comment.select('*').from(relation).to_a
-    assert_equal relation.to_a, Comment.select('subquery.*').from(relation).to_a
-    assert_equal relation.to_a, Comment.select('a.*').from(relation, :a).to_a
+    assert_equal relation.to_a, Comment.select("*").from(relation).to_a
+    assert_equal relation.to_a, Comment.select("subquery.*").from(relation).to_a
+    assert_equal relation.to_a, Comment.select("a.*").from(relation, :a).to_a
   end
 
   def test_finding_with_subquery_without_select_does_not_change_the_select
@@ -183,25 +184,37 @@ class RelationTest < ActiveRecord::TestCase
   end
 
   def test_select_with_subquery_in_from_does_not_use_original_table_name
-    relation = Comment.group(:type).select('COUNT(post_id) AS post_count, type')
-    subquery = Comment.from(relation).select('type','post_count')
-    assert_equal(relation.map(&:post_count).sort,subquery.map(&:post_count).sort)
+    relation = Comment.group(:type).select("COUNT(post_id) AS post_count, type")
+    subquery = Comment.from(relation).select("type", "post_count")
+    assert_equal(relation.map(&:post_count).sort, subquery.map(&:post_count).sort)
   end
 
   def test_group_with_subquery_in_from_does_not_use_original_table_name
-    relation = Comment.group(:type).select('COUNT(post_id) AS post_count,type')
-    subquery = Comment.from(relation).group('type').average("post_count")
-    assert_equal(relation.map(&:post_count).sort,subquery.values.sort)
+    relation = Comment.group(:type).select("COUNT(post_id) AS post_count,type")
+    subquery = Comment.from(relation).group("type").average("post_count")
+    assert_equal(relation.map(&:post_count).sort, subquery.values.sort)
+  end
+
+  def test_finding_with_subquery_with_eager_loading_in_from
+    relation = Comment.includes(:post).where("posts.type": "Post")
+    assert_equal relation.to_a, Comment.select("*").from(relation).to_a
+    assert_equal relation.to_a, Comment.select("subquery.*").from(relation).to_a
+    assert_equal relation.to_a, Comment.select("a.*").from(relation, :a).to_a
+  end
+
+  def test_finding_with_subquery_with_eager_loading_in_where
+    relation = Comment.includes(:post).where("posts.type": "Post")
+    assert_equal relation.sort_by(&:id), Comment.where(id: relation).sort_by(&:id)
   end
 
   def test_finding_with_conditions
-    assert_equal ["David"], Author.where(:name => 'David').map(&:name)
-    assert_equal ['Mary'],  Author.where(["name = ?", 'Mary']).map(&:name)
-    assert_equal ['Mary'],  Author.where("name = ?", 'Mary').map(&:name)
+    assert_equal ["David"], Author.where(name: "David").map(&:name)
+    assert_equal ["Mary"],  Author.where(["name = ?", "Mary"]).map(&:name)
+    assert_equal ["Mary"],  Author.where("name = ?", "Mary").map(&:name)
   end
 
   def test_finding_with_order
-    topics = Topic.order('id')
+    topics = Topic.order("id")
     assert_equal 5, topics.to_a.size
     assert_equal topics(:first).title, topics.first.title
   end
@@ -213,41 +226,73 @@ class RelationTest < ActiveRecord::TestCase
   end
 
   def test_finding_with_assoc_order
-    topics = Topic.order(:id => :desc)
+    topics = Topic.order(id: :desc)
     assert_equal 5, topics.to_a.size
     assert_equal topics(:fifth).title, topics.first.title
   end
 
-  def test_finding_with_reverted_assoc_order
-    topics = Topic.order(:id => :asc).reverse_order
+  def test_finding_with_arel_assoc_order
+    topics = Topic.order(Arel.sql("id") => :desc)
+    assert_equal 5, topics.to_a.size
+    assert_equal topics(:fifth).title, topics.first.title
+  end
+
+  def test_finding_with_reversed_assoc_order
+    topics = Topic.order(id: :asc).reverse_order
+    assert_equal 5, topics.to_a.size
+    assert_equal topics(:fifth).title, topics.first.title
+  end
+
+  def test_finding_with_reversed_arel_assoc_order
+    topics = Topic.order(Arel.sql("id") => :asc).reverse_order
     assert_equal 5, topics.to_a.size
     assert_equal topics(:fifth).title, topics.first.title
   end
 
   def test_reverse_order_with_function
-    topics = Topic.order("length(title)").reverse_order
+    topics = Topic.order(Arel.sql("length(title)")).reverse_order
+    assert_equal topics(:second).title, topics.first.title
+  end
+
+  def test_reverse_arel_assoc_order_with_function
+    topics = Topic.order(Arel.sql("length(title)") => :asc).reverse_order
     assert_equal topics(:second).title, topics.first.title
   end
 
   def test_reverse_order_with_function_other_predicates
-    topics = Topic.order("author_name, length(title), id").reverse_order
+    topics = Topic.order(Arel.sql("author_name, length(title), id")).reverse_order
     assert_equal topics(:second).title, topics.first.title
-    topics = Topic.order("length(author_name), id, length(title)").reverse_order
+    topics = Topic.order(Arel.sql("length(author_name), id, length(title)")).reverse_order
     assert_equal topics(:fifth).title, topics.first.title
   end
 
   def test_reverse_order_with_multiargument_function
     assert_raises(ActiveRecord::IrreversibleOrderError) do
-      Topic.order("concat(author_name, title)").reverse_order
+      Topic.order(Arel.sql("concat(author_name, title)")).reverse_order
+    end
+    assert_raises(ActiveRecord::IrreversibleOrderError) do
+      Topic.order(Arel.sql("concat(lower(author_name), title)")).reverse_order
+    end
+    assert_raises(ActiveRecord::IrreversibleOrderError) do
+      Topic.order(Arel.sql("concat(author_name, lower(title))")).reverse_order
+    end
+    assert_raises(ActiveRecord::IrreversibleOrderError) do
+      Topic.order(Arel.sql("concat(lower(author_name), title, length(title)")).reverse_order
+    end
+  end
+
+  def test_reverse_arel_assoc_order_with_multiargument_function
+    assert_nothing_raised do
+      Topic.order(Arel.sql("REPLACE(title, '', '')") => :asc).reverse_order
     end
   end
 
   def test_reverse_order_with_nulls_first_or_last
     assert_raises(ActiveRecord::IrreversibleOrderError) do
-      Topic.order("title NULLS FIRST").reverse_order
+      Topic.order(Arel.sql("title NULLS FIRST")).reverse_order
     end
     assert_raises(ActiveRecord::IrreversibleOrderError) do
-      Topic.order("title nulls last").reverse_order
+      Topic.order(Arel.sql("title nulls last")).reverse_order
     end
   end
 
@@ -258,7 +303,7 @@ class RelationTest < ActiveRecord::TestCase
   end
 
   def test_order_with_hash_and_symbol_generates_the_same_sql
-    assert_equal Topic.order(:id).to_sql, Topic.order(:id => :asc).to_sql
+    assert_equal Topic.order(:id).to_sql, Topic.order(id: :asc).to_sql
   end
 
   def test_finding_with_desc_order_with_string
@@ -268,7 +313,7 @@ class RelationTest < ActiveRecord::TestCase
   end
 
   def test_finding_with_asc_order_with_string
-    topics = Topic.order(id: 'asc')
+    topics = Topic.order(id: "asc")
     assert_equal 5, topics.to_a.size
     assert_equal [topics(:first), topics(:second), topics(:third), topics(:fourth), topics(:fifth)], topics.to_a
   end
@@ -282,7 +327,7 @@ class RelationTest < ActiveRecord::TestCase
     assert_includes Topic.order(id: "DESC").to_sql, "DESC"
     assert_includes Topic.order(id: "desc").to_sql, "DESC"
     assert_includes Topic.order(id: :DESC).to_sql, "DESC"
-    assert_includes Topic.order(id: :desc).to_sql,"DESC"
+    assert_includes Topic.order(id: :desc).to_sql, "DESC"
   end
 
   def test_raising_exception_on_invalid_hash_params
@@ -296,7 +341,7 @@ class RelationTest < ActiveRecord::TestCase
   end
 
   def test_finding_with_order_concatenated
-    topics = Topic.order('author_name').order('title')
+    topics = Topic.order("author_name").order("title")
     assert_equal 5, topics.to_a.size
     assert_equal topics(:fourth).title, topics.first.title
   end
@@ -314,19 +359,19 @@ class RelationTest < ActiveRecord::TestCase
   end
 
   def test_finding_with_reorder
-    topics = Topic.order('author_name').order('title').reorder('id').to_a
+    topics = Topic.order("author_name").order("title").reorder("id").to_a
     topics_titles = topics.map(&:title)
-    assert_equal ['The First Topic', 'The Second Topic of the day', 'The Third Topic of the day', 'The Fourth Topic of the day', 'The Fifth Topic of the day'], topics_titles
+    assert_equal ["The First Topic", "The Second Topic of the day", "The Third Topic of the day", "The Fourth Topic of the day", "The Fifth Topic of the day"], topics_titles
   end
 
   def test_finding_with_reorder_by_aliased_attributes
-    topics = Topic.order('author_name').reorder(:heading)
+    topics = Topic.order("author_name").reorder(:heading)
     assert_equal 5, topics.to_a.size
     assert_equal topics(:fifth).title, topics.first.title
   end
 
   def test_finding_with_assoc_reorder_by_aliased_attributes
-    topics = Topic.order('author_name').reorder(heading: :desc)
+    topics = Topic.order("author_name").reorder(heading: :desc)
     assert_equal 5, topics.to_a.size
     assert_equal topics(:third).title, topics.first.title
   end
@@ -340,29 +385,29 @@ class RelationTest < ActiveRecord::TestCase
 
   def test_finding_with_cross_table_order_and_limit
     tags = Tag.includes(:taggings).
-              order("tags.name asc", "taggings.taggable_id asc", "REPLACE('abc', taggings.taggable_type, taggings.taggable_type)").
+              order("tags.name asc", "taggings.taggable_id asc", Arel.sql("REPLACE('abc', taggings.taggable_type, taggings.taggable_type)")).
               limit(1).to_a
     assert_equal 1, tags.length
   end
 
   def test_finding_with_complex_order_and_limit
-    tags = Tag.includes(:taggings).references(:taggings).order("REPLACE('abc', taggings.taggable_type, taggings.taggable_type)").limit(1).to_a
+    tags = Tag.includes(:taggings).references(:taggings).order(Arel.sql("REPLACE('abc', taggings.taggable_type, taggings.taggable_type)")).limit(1).to_a
     assert_equal 1, tags.length
   end
 
   def test_finding_with_complex_order
-    tags = Tag.includes(:taggings).references(:taggings).order("REPLACE('abc', taggings.taggable_type, taggings.taggable_type)").to_a
+    tags = Tag.includes(:taggings).references(:taggings).order(Arel.sql("REPLACE('abc', taggings.taggable_type, taggings.taggable_type)")).to_a
     assert_equal 3, tags.length
   end
 
   def test_finding_with_sanitized_order
-    query = Tag.order(["field(id, ?)", [1,3,2]]).to_sql
+    query = Tag.order([Arel.sql("field(id, ?)"), [1, 3, 2]]).to_sql
     assert_match(/field\(id, 1,3,2\)/, query)
 
-    query = Tag.order(["field(id, ?)", []]).to_sql
+    query = Tag.order([Arel.sql("field(id, ?)"), []]).to_sql
     assert_match(/field\(id, NULL\)/, query)
 
-    query = Tag.order(["field(id, ?)", nil]).to_sql
+    query = Tag.order([Arel.sql("field(id, ?)"), nil]).to_sql
     assert_match(/field\(id, NULL\)/, query)
   end
 
@@ -384,149 +429,32 @@ class RelationTest < ActiveRecord::TestCase
   end
 
   def test_select_with_block
-    even_ids = Developer.all.select {|d| d.id % 2 == 0 }.map(&:id)
+    even_ids = Developer.all.select { |d| d.id % 2 == 0 }.map(&:id)
     assert_equal [2, 4, 6, 8, 10], even_ids.sort
   end
 
-  def test_none
-    assert_no_queries(ignore_none: false) do
-      assert_equal [], Developer.none
-      assert_equal [], Developer.all.none
-    end
-  end
-
-  def test_none_chainable
-    assert_no_queries(ignore_none: false) do
-      assert_equal [], Developer.none.where(:name => 'David')
-    end
-  end
-
-  def test_none_chainable_to_existing_scope_extension_method
-    assert_no_queries(ignore_none: false) do
-      assert_equal 1, Topic.anonymous_extension.none.one
-    end
-  end
-
-  def test_none_chained_to_methods_firing_queries_straight_to_db
-    assert_no_queries(ignore_none: false) do
-      assert_equal [],    Developer.none.pluck(:id, :name)
-      assert_equal 0,     Developer.none.delete_all
-      assert_equal 0,     Developer.none.update_all(:name => 'David')
-      assert_equal 0,     Developer.none.delete(1)
-      assert_equal false, Developer.none.exists?(1)
-    end
-  end
-
-  def test_null_relation_content_size_methods
-    assert_no_queries(ignore_none: false) do
-      assert_equal 0,     Developer.none.size
-      assert_equal 0,     Developer.none.count
-      assert_equal true,  Developer.none.empty?
-      assert_equal true, Developer.none.none?
-      assert_equal false, Developer.none.any?
-      assert_equal false, Developer.none.one?
-      assert_equal false, Developer.none.many?
-    end
-  end
-
-  def test_null_relation_calculations_methods
-    assert_no_queries(ignore_none: false) do
-      assert_equal 0, Developer.none.count
-      assert_equal 0, Developer.none.calculate(:count, nil)
-      assert_equal nil, Developer.none.calculate(:average, 'salary')
-    end
-  end
-
-  def test_null_relation_metadata_methods
-    assert_equal "", Developer.none.to_sql
-    assert_equal({}, Developer.none.where_values_hash)
-  end
-
-  def test_null_relation_where_values_hash
-    assert_equal({ 'salary' => 100_000 }, Developer.none.where(salary: 100_000).where_values_hash)
-  end
-
-  def test_null_relation_sum
-    ac = Aircraft.new
-    assert_equal Hash.new, ac.engines.group(:id).sum(:id)
-    assert_equal        0, ac.engines.count
-    ac.save
-    assert_equal Hash.new, ac.engines.group(:id).sum(:id)
-    assert_equal        0, ac.engines.count
-  end
-
-  def test_null_relation_count
-    ac = Aircraft.new
-    assert_equal Hash.new, ac.engines.group(:id).count
-    assert_equal        0, ac.engines.count
-    ac.save
-    assert_equal Hash.new, ac.engines.group(:id).count
-    assert_equal        0, ac.engines.count
-  end
-
-  def test_null_relation_size
-    ac = Aircraft.new
-    assert_equal Hash.new, ac.engines.group(:id).size
-    assert_equal        0, ac.engines.size
-    ac.save
-    assert_equal Hash.new, ac.engines.group(:id).size
-    assert_equal        0, ac.engines.size
-  end
-
-  def test_null_relation_average
-    ac = Aircraft.new
-    assert_equal Hash.new, ac.engines.group(:car_id).average(:id)
-    assert_equal        nil, ac.engines.average(:id)
-    ac.save
-    assert_equal Hash.new, ac.engines.group(:car_id).average(:id)
-    assert_equal        nil, ac.engines.average(:id)
-  end
-
-  def test_null_relation_minimum
-    ac = Aircraft.new
-    assert_equal Hash.new, ac.engines.group(:car_id).minimum(:id)
-    assert_equal        nil, ac.engines.minimum(:id)
-    ac.save
-    assert_equal Hash.new, ac.engines.group(:car_id).minimum(:id)
-    assert_equal        nil, ac.engines.minimum(:id)
-  end
-
-  def test_null_relation_maximum
-    ac = Aircraft.new
-    assert_equal Hash.new, ac.engines.group(:car_id).maximum(:id)
-    assert_equal        nil, ac.engines.maximum(:id)
-    ac.save
-    assert_equal Hash.new, ac.engines.group(:car_id).maximum(:id)
-    assert_equal        nil, ac.engines.maximum(:id)
-  end
-
-  def test_null_relation_in_where_condition
-    assert_operator Comment.count, :>, 0 # precondition, make sure there are comments.
-    assert_equal 0, Comment.where(post_id: Post.none).to_a.size
-  end
-
   def test_joins_with_nil_argument
     assert_nothing_raised { DependentFirm.joins(nil).first }
   end
 
   def test_finding_with_hash_conditions_on_joined_table
-    firms = DependentFirm.joins(:account).where({:name => 'RailsCore', :accounts => { :credit_limit => 55..60 }}).to_a
+    firms = DependentFirm.joins(:account).where(name: "RailsCore", accounts: { credit_limit: 55..60 }).to_a
     assert_equal 1, firms.size
     assert_equal companies(:rails_core), firms.first
   end
 
   def test_find_all_with_join
-    developers_on_project_one = Developer.joins('LEFT JOIN developers_projects ON developers.id = developers_projects.developer_id').
-      where('project_id=1').to_a
+    developers_on_project_one = Developer.joins("LEFT JOIN developers_projects ON developers.id = developers_projects.developer_id").
+      where("project_id=1").to_a
 
     assert_equal 3, developers_on_project_one.length
     developer_names = developers_on_project_one.map(&:name)
-    assert developer_names.include?('David')
-    assert developer_names.include?('Jamis')
+    assert_includes developer_names, "David"
+    assert_includes developer_names, "Jamis"
   end
 
   def test_find_on_hash_conditions
-    assert_equal Topic.all.merge!(:where => {:approved => false}).to_a, Topic.where({ :approved => false }).to_a
+    assert_equal Topic.all.merge!(where: { approved: false }).to_a, Topic.where(approved: false).to_a
   end
 
   def test_joins_with_string_array
@@ -554,18 +482,10 @@ class RelationTest < ActiveRecord::TestCase
     assert_nothing_raised { Topic.reorder([]) }
   end
 
-  def test_scoped_responds_to_delegated_methods
-    relation = Topic.all
-
-    ["map", "uniq", "sort", "insert", "delete", "update"].each do |method|
-      assert_respond_to relation, method, "Topic.all should respond to #{method.inspect}"
-    end
-  end
-
-  def test_respond_to_delegates_to_relation
+  def test_respond_to_delegates_to_arel
     relation = Topic.all
     fake_arel = Struct.new(:responds) {
-      def respond_to? method, access = false
+      def respond_to?(method, access = false)
         responds << [method, access]
       end
     }.new []
@@ -575,10 +495,6 @@ class RelationTest < ActiveRecord::TestCase
 
     relation.respond_to?(:matching_attributes)
     assert_equal [:matching_attributes, false], fake_arel.responds.first
-
-    fake_arel.responds = []
-    relation.respond_to?(:matching_attributes, true)
-    assert_equal [:matching_attributes, true], fake_arel.responds.first
   end
 
   def test_respond_to_dynamic_finders
@@ -599,8 +515,8 @@ class RelationTest < ActiveRecord::TestCase
   end
 
   def test_eager_association_loading_of_stis_with_multiple_references
-    authors = Author.eager_load(:posts => { :special_comments => { :post => [ :special_comments, :very_special_comment ] } }).
-      order('comments.body, very_special_comments_posts.body').where('posts.id = 4').to_a
+    authors = Author.eager_load(posts: { special_comments: { post: [ :special_comments, :very_special_comment ] } }).
+      order("comments.body, very_special_comments_posts.body").where("posts.id = 4").to_a
 
     assert_equal [authors(:david)], authors
     assert_no_queries do
@@ -611,27 +527,27 @@ class RelationTest < ActiveRecord::TestCase
 
   def test_find_with_preloaded_associations
     assert_queries(2) do
-      posts = Post.preload(:comments).order('posts.id')
+      posts = Post.preload(:comments).order("posts.id")
       assert posts.first.comments.first
     end
 
     assert_queries(2) do
-      posts = Post.preload(:comments).order('posts.id')
+      posts = Post.preload(:comments).order("posts.id")
       assert posts.first.comments.first
     end
 
     assert_queries(2) do
-      posts = Post.preload(:author).order('posts.id')
+      posts = Post.preload(:author).order("posts.id")
       assert posts.first.author
     end
 
     assert_queries(2) do
-      posts = Post.preload(:author).order('posts.id')
+      posts = Post.preload(:author).order("posts.id")
       assert posts.first.author
     end
 
     assert_queries(3) do
-      posts = Post.preload(:author, :comments).order('posts.id')
+      posts = Post.preload(:author, :comments).order("posts.id")
       assert posts.first.author
       assert posts.first.comments.first
     end
@@ -646,58 +562,48 @@ class RelationTest < ActiveRecord::TestCase
 
   def test_find_with_included_associations
     assert_queries(2) do
-      posts = Post.includes(:comments).order('posts.id')
+      posts = Post.includes(:comments).order("posts.id")
       assert posts.first.comments.first
     end
 
     assert_queries(2) do
-      posts = Post.all.includes(:comments).order('posts.id')
+      posts = Post.all.includes(:comments).order("posts.id")
       assert posts.first.comments.first
     end
 
     assert_queries(2) do
-      posts = Post.includes(:author).order('posts.id')
+      posts = Post.includes(:author).order("posts.id")
       assert posts.first.author
     end
 
     assert_queries(3) do
-      posts = Post.includes(:author, :comments).order('posts.id')
+      posts = Post.includes(:author, :comments).order("posts.id")
       assert posts.first.author
       assert posts.first.comments.first
     end
   end
 
-  def test_default_scope_with_conditions_string
-    assert_equal Developer.where(name: 'David').map(&:id).sort, DeveloperCalledDavid.all.map(&:id).sort
-    assert_nil DeveloperCalledDavid.create!.name
-  end
-
-  def test_default_scope_with_conditions_hash
-    assert_equal Developer.where(name: 'Jamis').map(&:id).sort, DeveloperCalledJamis.all.map(&:id).sort
-    assert_equal 'Jamis', DeveloperCalledJamis.create!.name
-  end
-
   def test_default_scoping_finder_methods
-    developers = DeveloperCalledDavid.order('id').map(&:id).sort
-    assert_equal Developer.where(name: 'David').map(&:id).sort, developers
+    developers = DeveloperCalledDavid.order("id").map(&:id).sort
+    assert_equal Developer.where(name: "David").map(&:id).sort, developers
   end
 
   def test_includes_with_select
-    query = Post.select('comments_count AS ranking').order('ranking').includes(:comments)
+    query = Post.select("comments_count AS ranking").order("ranking").includes(:comments)
       .where(comments: { id: 1 })
 
-    assert_equal ['comments_count AS ranking'], query.select_values
+    assert_equal ["comments_count AS ranking"], query.select_values
     assert_equal 1, query.to_a.size
   end
 
   def test_preloading_with_associations_and_merges
-    post = Post.create! title: 'Uhuu', body: 'body'
+    post = Post.create! title: "Uhuu", body: "body"
     reader = Reader.create! post_id: post.id, person_id: 1
-    comment = Comment.create! post_id: post.id, body: 'body'
+    comment = Comment.create! post_id: post.id, body: "body"
 
     assert !comment.respond_to?(:readers)
 
-    post_rel = Post.preload(:readers).joins(:readers).where(title: 'Uhuu')
+    post_rel = Post.preload(:readers).joins(:readers).where(title: "Uhuu")
     result_comment = Comment.joins(:post).merge(post_rel).to_a.first
     assert_equal comment, result_comment
 
@@ -706,7 +612,7 @@ class RelationTest < ActiveRecord::TestCase
       assert_equal [reader], result_comment.post.readers.to_a
     end
 
-    post_rel = Post.includes(:readers).where(title: 'Uhuu')
+    post_rel = Post.includes(:readers).where(title: "Uhuu")
     result_comment = Comment.joins(:post).merge(post_rel).first
     assert_equal comment, result_comment
 
@@ -717,17 +623,17 @@ class RelationTest < ActiveRecord::TestCase
   end
 
   def test_preloading_with_associations_default_scopes_and_merges
-    post = Post.create! title: 'Uhuu', body: 'body'
+    post = Post.create! title: "Uhuu", body: "body"
     reader = Reader.create! post_id: post.id, person_id: 1
 
-    post_rel = PostWithPreloadDefaultScope.preload(:readers).joins(:readers).where(title: 'Uhuu')
+    post_rel = PostWithPreloadDefaultScope.preload(:readers).joins(:readers).where(title: "Uhuu")
     result_post = PostWithPreloadDefaultScope.all.merge(post_rel).to_a.first
 
     assert_no_queries do
       assert_equal [reader], result_post.readers.to_a
     end
 
-    post_rel = PostWithIncludesDefaultScope.includes(:readers).where(title: 'Uhuu')
+    post_rel = PostWithIncludesDefaultScope.includes(:readers).where(title: "Uhuu")
     result_post = PostWithIncludesDefaultScope.all.merge(post_rel).to_a.first
 
     assert_no_queries do
@@ -739,11 +645,11 @@ class RelationTest < ActiveRecord::TestCase
     posts = Post.preload(:comments)
     post = posts.find { |p| p.id == 1 }
     assert_equal 2, post.comments.size
-    assert post.comments.include?(comments(:greetings))
+    assert_includes post.comments, comments(:greetings)
 
     post = Post.where("posts.title = 'Welcome to the weblog'").preload(:comments).first
     assert_equal 2, post.comments.size
-    assert post.comments.include?(comments(:greetings))
+    assert_includes post.comments, comments(:greetings)
 
     posts = Post.preload(:last_comment)
     post = posts.find { |p| p.id == 1 }
@@ -752,9 +658,9 @@ class RelationTest < ActiveRecord::TestCase
 
   def test_to_sql_on_eager_join
     expected = assert_sql {
-      Post.eager_load(:last_comment).order('comments.id DESC').to_a
+      Post.eager_load(:last_comment).order("comments.id DESC").to_a
     }.first
-    actual = Post.eager_load(:last_comment).order('comments.id DESC').to_sql
+    actual = Post.eager_load(:last_comment).order("comments.id DESC").to_sql
     assert_equal expected, actual
   end
 
@@ -765,7 +671,7 @@ class RelationTest < ActiveRecord::TestCase
   end
 
   def test_loading_with_one_association_with_non_preload
-    posts = Post.eager_load(:last_comment).order('comments.id DESC')
+    posts = Post.eager_load(:last_comment).order("comments.id DESC")
     post = posts.find { |p| p.id == 1 }
     assert_equal Post.find(1).last_comment, post.last_comment
   end
@@ -776,7 +682,6 @@ class RelationTest < ActiveRecord::TestCase
     expected_taggings = taggings(:welcome_general, :thinking_general)
 
     assert_no_queries do
-      assert_equal expected_taggings, author.taggings.distinct.sort_by(&:id)
       assert_equal expected_taggings, author.taggings.uniq.sort_by(&:id)
     end
 
@@ -789,40 +694,40 @@ class RelationTest < ActiveRecord::TestCase
     author = Author.all.find_by_id!(authors(:david).id)
     assert_equal "David", author.name
 
-    assert_raises(ActiveRecord::RecordNotFound) { Author.all.find_by_id_and_name!(20, 'invalid') }
+    assert_raises(ActiveRecord::RecordNotFound) { Author.all.find_by_id_and_name!(20, "invalid") }
   end
 
   def test_find_id
     authors = Author.all
 
     david = authors.find(authors(:david).id)
-    assert_equal 'David', david.name
+    assert_equal "David", david.name
 
-    assert_raises(ActiveRecord::RecordNotFound) { authors.where(:name => 'lifo').find('42') }
+    assert_raises(ActiveRecord::RecordNotFound) { authors.where(name: "lifo").find("42") }
   end
 
   def test_find_ids
-    authors = Author.order('id ASC')
+    authors = Author.order("id ASC")
 
     results = authors.find(authors(:david).id, authors(:mary).id)
     assert_kind_of Array, results
     assert_equal 2, results.size
-    assert_equal 'David', results[0].name
-    assert_equal 'Mary', results[1].name
+    assert_equal "David", results[0].name
+    assert_equal "Mary", results[1].name
     assert_equal results, authors.find([authors(:david).id, authors(:mary).id])
 
-    assert_raises(ActiveRecord::RecordNotFound) { authors.where(:name => 'lifo').find(authors(:david).id, '42') }
-    assert_raises(ActiveRecord::RecordNotFound) { authors.find(['42', 43]) }
+    assert_raises(ActiveRecord::RecordNotFound) { authors.where(name: "lifo").find(authors(:david).id, "42") }
+    assert_raises(ActiveRecord::RecordNotFound) { authors.find(["42", 43]) }
   end
 
   def test_find_in_empty_array
-    authors = Author.all.where(:id => [])
+    authors = Author.all.where(id: [])
     assert authors.to_a.blank?
   end
 
   def test_where_with_ar_object
     author = Author.first
-    authors = Author.all.where(:id => author)
+    authors = Author.all.where(id: author)
     assert_equal 1, authors.to_a.length
   end
 
@@ -832,15 +737,6 @@ class RelationTest < ActiveRecord::TestCase
     assert_equal author, authors.first
   end
 
-  class Mary < Author; end
-
-  def test_find_by_classname
-    Author.create!(:name => Mary.name)
-    assert_deprecated do
-      assert_equal 1, Author.where(:name => Mary).size
-    end
-  end
-
   def test_find_by_id_with_list_of_ar
     author = Author.first
     authors = Author.find_by_id([author])
@@ -850,25 +746,25 @@ class RelationTest < ActiveRecord::TestCase
   def test_find_all_using_where_twice_should_or_the_relation
     david = authors(:david)
     relation = Author.unscoped
-    relation = relation.where(:name => david.name)
-    relation = relation.where(:name => 'Santiago')
-    relation = relation.where(:id => david.id)
+    relation = relation.where(name: david.name)
+    relation = relation.where(name: "Santiago")
+    relation = relation.where(id: david.id)
     assert_equal [], relation.to_a
   end
 
   def test_multi_where_ands_queries
     relation = Author.unscoped
     david = authors(:david)
-    sql = relation.where(:name => david.name).where(:name => 'Santiago').to_sql
-    assert_match('AND', sql)
+    sql = relation.where(name: david.name).where(name: "Santiago").to_sql
+    assert_match("AND", sql)
   end
 
   def test_find_all_with_multiple_should_use_and
     david = authors(:david)
     relation = [
-      { :name => david.name },
-      { :name => 'Santiago' },
-      { :name => 'tenderlove' },
+      { name: david.name },
+      { name: "Santiago" },
+      { name: "tenderlove" },
     ].inject(Author.unscoped) do |memo, param|
       memo.where(param)
     end
@@ -884,20 +780,18 @@ class RelationTest < ActiveRecord::TestCase
 
   def test_find_all_using_where_with_relation
     david = authors(:david)
-    # switching the lines below would succeed in current rails
-    # assert_queries(2) {
     assert_queries(1) {
-      relation = Author.where(:id => Author.where(:id => david.id))
+      relation = Author.where(id: Author.where(id: david.id))
       assert_equal [david], relation.to_a
     }
 
     assert_queries(1) {
-      relation = Author.where('id in (?)', Author.where(id: david).select(:id))
+      relation = Author.where("id in (?)", Author.where(id: david).select(:id))
       assert_equal [david], relation.to_a
     }
 
     assert_queries(1) do
-      relation = Author.where('id in (:author_ids)', author_ids: Author.where(id: david).select(:id))
+      relation = Author.where("id in (:author_ids)", author_ids: Author.where(id: david).select(:id))
       assert_equal [david], relation.to_a
     end
   end
@@ -912,22 +806,20 @@ class RelationTest < ActiveRecord::TestCase
     end
 
     assert_queries(1) do
-      relation = Post.where('id in (?)', david.posts.select(:id))
-      assert_equal davids_posts, relation.order(:id).to_a, 'should process Relation as bind variables'
+      relation = Post.where("id in (?)", david.posts.select(:id))
+      assert_equal davids_posts, relation.order(:id).to_a, "should process Relation as bind variables"
     end
 
     assert_queries(1) do
-      relation = Post.where('id in (:post_ids)', post_ids: david.posts.select(:id))
-      assert_equal davids_posts, relation.order(:id).to_a, 'should process Relation as named bind variables'
+      relation = Post.where("id in (:post_ids)", post_ids: david.posts.select(:id))
+      assert_equal davids_posts, relation.order(:id).to_a, "should process Relation as named bind variables"
     end
   end
 
   def test_find_all_using_where_with_relation_and_alternate_primary_key
     cool_first = minivans(:cool_first)
-    # switching the lines below would succeed in current rails
-    # assert_queries(2) {
     assert_queries(1) {
-      relation = Minivan.where(:minivan_id => Minivan.where(:name => cool_first.name))
+      relation = Minivan.where(minivan_id: Minivan.where(name: cool_first.name))
       assert_equal [cool_first], relation.to_a
     }
   end
@@ -935,10 +827,10 @@ class RelationTest < ActiveRecord::TestCase
   def test_find_all_using_where_with_relation_does_not_alter_select_values
     david = authors(:david)
 
-    subquery = Author.where(:id => david.id)
+    subquery = Author.where(id: david.id)
 
     assert_queries(1) {
-      relation = Author.where(:id => subquery)
+      relation = Author.where(id: subquery)
       assert_equal [david], relation.to_a
     }
 
@@ -948,102 +840,61 @@ class RelationTest < ActiveRecord::TestCase
   def test_find_all_using_where_with_relation_with_joins
     david = authors(:david)
     assert_queries(1) {
-      relation = Author.where(:id => Author.joins(:posts).where(:id => david.id))
+      relation = Author.where(id: Author.joins(:posts).where(id: david.id))
       assert_equal [david], relation.to_a
     }
   end
 
-
   def test_find_all_using_where_with_relation_with_select_to_build_subquery
     david = authors(:david)
     assert_queries(1) {
-      relation = Author.where(:name => Author.where(:id => david.id).select(:name))
+      relation = Author.where(name: Author.where(id: david.id).select(:name))
       assert_equal [david], relation.to_a
     }
   end
 
-  def test_exists
-    davids = Author.where(:name => 'David')
-    assert davids.exists?
-    assert davids.exists?(authors(:david).id)
-    assert ! davids.exists?(authors(:mary).id)
-    assert ! davids.exists?("42")
-    assert ! davids.exists?(42)
-    assert ! davids.exists?(davids.new.id)
-
-    fake  = Author.where(:name => 'fake author')
-    assert ! fake.exists?
-    assert ! fake.exists?(authors(:david).id)
-  end
-
-  def test_exists_uses_existing_scope
-    post = authors(:david).posts.first
-    authors = Author.includes(:posts).where(name: "David", posts: { id: post.id })
-    assert authors.exists?(authors(:david).id)
-  end
-
-  def test_any_with_scope_on_hash_includes
-    post = authors(:david).posts.first
-    categories = Categorization.includes(author: :posts).where(posts: { id: post.id })
-    assert categories.exists?
-  end
-
   def test_last
     authors = Author.all
     assert_equal authors(:bob), authors.last
   end
 
   def test_destroy_all
-    davids = Author.where(:name => 'David')
+    davids = Author.where(name: "David")
 
     # Force load
     assert_equal [authors(:david)], davids.to_a
     assert davids.loaded?
 
-    assert_difference('Author.count', -1) { davids.destroy_all }
+    assert_difference("Author.count", -1) { davids.destroy_all }
 
     assert_equal [], davids.to_a
     assert davids.loaded?
   end
 
-  def test_destroy_all_with_conditions_is_deprecated
-    assert_deprecated do
-      assert_difference('Author.count', -1) { Author.destroy_all(name: 'David') }
-    end
-  end
-
   def test_delete_all
-    davids = Author.where(:name => 'David')
+    davids = Author.where(name: "David")
 
-    assert_difference('Author.count', -1) { davids.delete_all }
+    assert_difference("Author.count", -1) { davids.delete_all }
     assert ! davids.loaded?
   end
 
-  def test_delete_all_with_conditions_is_deprecated
-    assert_deprecated do
-      assert_difference('Author.count', -1) { Author.delete_all(name: 'David') }
-    end
-  end
-
   def test_delete_all_loaded
-    davids = Author.where(:name => 'David')
+    davids = Author.where(name: "David")
 
     # Force load
     assert_equal [authors(:david)], davids.to_a
     assert davids.loaded?
 
-    assert_difference('Author.count', -1) { davids.delete_all }
+    assert_difference("Author.count", -1) { davids.delete_all }
 
     assert_equal [], davids.to_a
     assert davids.loaded?
   end
 
   def test_delete_all_with_unpermitted_relation_raises_error
-    assert_raises(ActiveRecord::ActiveRecordError) { Author.limit(10).delete_all }
     assert_raises(ActiveRecord::ActiveRecordError) { Author.distinct.delete_all }
     assert_raises(ActiveRecord::ActiveRecordError) { Author.group(:name).delete_all }
-    assert_raises(ActiveRecord::ActiveRecordError) { Author.having('SUM(id) < 3').delete_all }
-    assert_raises(ActiveRecord::ActiveRecordError) { Author.offset(10).delete_all }
+    assert_raises(ActiveRecord::ActiveRecordError) { Author.having("SUM(id) < 3").delete_all }
   end
 
   def test_select_with_aggregates
@@ -1082,13 +933,13 @@ class RelationTest < ActiveRecord::TestCase
     assert_equal 11, posts.count(:all)
     assert_equal 11, posts.count(:id)
 
-    assert_equal 1, posts.where('comments_count > 1').count
-    assert_equal 9, posts.where(:comments_count => 0).count
+    assert_equal 3, posts.where("comments_count > 1").count
+    assert_equal 6, posts.where(comments_count: 0).count
   end
 
   def test_count_with_block
     posts = Post.all
-    assert_equal 10, posts.count { |p| p.comments_count.even? }
+    assert_equal 8, posts.count { |p| p.comments_count.even? }
   end
 
   def test_count_on_association_relation
@@ -1105,36 +956,42 @@ class RelationTest < ActiveRecord::TestCase
   def test_count_with_distinct
     posts = Post.all
 
-    assert_equal 3, posts.distinct(true).count(:comments_count)
+    assert_equal 4, posts.distinct(true).count(:comments_count)
     assert_equal 11, posts.distinct(false).count(:comments_count)
 
-    assert_equal 3, posts.distinct(true).select(:comments_count).count
+    assert_equal 4, posts.distinct(true).select(:comments_count).count
     assert_equal 11, posts.distinct(false).select(:comments_count).count
   end
 
+  def test_size_with_distinct
+    posts = Post.distinct.select(:author_id, :comments_count)
+    assert_queries(1) { assert_equal 8, posts.size }
+    assert_queries(1) { assert_equal 8, posts.load.size }
+  end
+
   def test_update_all_with_scope
     tag = Tag.first
     Post.tagged_with(tag.id).update_all title: "rofl"
     list = Post.tagged_with(tag.id).all.to_a
     assert_operator list.length, :>, 0
-    list.each { |post| assert_equal 'rofl', post.title }
+    list.each { |post| assert_equal "rofl", post.title }
   end
 
   def test_count_explicit_columns
-    Post.update_all(:comments_count => nil)
+    Post.update_all(comments_count: nil)
     posts = Post.all
 
-    assert_equal [0], posts.select('comments_count').where('id is not null').group('id').order('id').count.values.uniq
-    assert_equal 0, posts.where('id is not null').select('comments_count').count
+    assert_equal [0], posts.select("comments_count").where("id is not null").group("id").order("id").count.values.uniq
+    assert_equal 0, posts.where("id is not null").select("comments_count").count
 
-    assert_equal 11, posts.select('comments_count').count('id')
-    assert_equal 0, posts.select('comments_count').count
+    assert_equal 11, posts.select("comments_count").count("id")
+    assert_equal 0, posts.select("comments_count").count
     assert_equal 0, posts.count(:comments_count)
-    assert_equal 0, posts.count('comments_count')
+    assert_equal 0, posts.count("comments_count")
   end
 
   def test_multiple_selects
-    post = Post.all.select('comments_count').select('title').order("id ASC").first
+    post = Post.all.select("comments_count").select("title").order("id ASC").first
     assert_equal "Welcome to the weblog", post.title
     assert_equal 2, post.comments_count
   end
@@ -1145,9 +1002,9 @@ class RelationTest < ActiveRecord::TestCase
     assert_queries(1) { assert_equal 11, posts.size }
     assert ! posts.loaded?
 
-    best_posts = posts.where(:comments_count => 0)
-    best_posts.to_a # force load
-    assert_no_queries { assert_equal 9, best_posts.size }
+    best_posts = posts.where(comments_count: 0)
+    best_posts.load # force load
+    assert_no_queries { assert_equal 6, best_posts.size }
   end
 
   def test_size_with_limit
@@ -1156,9 +1013,9 @@ class RelationTest < ActiveRecord::TestCase
     assert_queries(1) { assert_equal 10, posts.size }
     assert ! posts.loaded?
 
-    best_posts = posts.where(:comments_count => 0)
-    best_posts.to_a # force load
-    assert_no_queries { assert_equal 9, best_posts.size }
+    best_posts = posts.where(comments_count: 0)
+    best_posts.load # force load
+    assert_no_queries { assert_equal 6, best_posts.size }
   end
 
   def test_size_with_zero_limit
@@ -1167,7 +1024,7 @@ class RelationTest < ActiveRecord::TestCase
     assert_no_queries { assert_equal 0, posts.size }
     assert ! posts.loaded?
 
-    posts.to_a # force load
+    posts.load # force load
     assert_no_queries { assert_equal 0, posts.size }
   end
 
@@ -1179,9 +1036,9 @@ class RelationTest < ActiveRecord::TestCase
   end
 
   def test_count_complex_chained_relations
-    posts = Post.select('comments_count').where('id is not null').group("author_id").where("comments_count > 0")
+    posts = Post.select("comments_count").where("id is not null").group("author_id").where("comments_count > 0")
 
-    expected = { 1 => 2 }
+    expected = { 1 => 4, 2 => 1 }
     assert_equal expected, posts.count
   end
 
@@ -1191,12 +1048,12 @@ class RelationTest < ActiveRecord::TestCase
     assert_queries(1) { assert_equal false, posts.empty? }
     assert ! posts.loaded?
 
-    no_posts = posts.where(:title => "")
+    no_posts = posts.where(title: "")
     assert_queries(1) { assert_equal true, no_posts.empty? }
     assert ! no_posts.loaded?
 
-    best_posts = posts.where(:comments_count => 0)
-    best_posts.to_a # force load
+    best_posts = posts.where(comments_count: 0)
+    best_posts.load # force load
     assert_no_queries { assert_equal false, best_posts.empty? }
   end
 
@@ -1206,7 +1063,7 @@ class RelationTest < ActiveRecord::TestCase
     assert_queries(1) { assert_equal false, posts.empty? }
     assert ! posts.loaded?
 
-    no_posts = posts.where(:title => "")
+    no_posts = posts.where(title: "")
     assert_queries(1) { assert_equal true, no_posts.empty? }
     assert ! no_posts.loaded?
   end
@@ -1220,14 +1077,14 @@ class RelationTest < ActiveRecord::TestCase
     # the SHOW TABLES result to be cached so we don't have to do it again in the block.
     #
     # This is obviously a rubbish fix but it's the best I can come up with for now...
-    posts.where(:id => nil).any?
+    posts.where(id: nil).any?
 
     assert_queries(3) do
       assert posts.any? # Uses COUNT()
-      assert ! posts.where(:id => nil).any?
+      assert ! posts.where(id: nil).any?
 
-      assert posts.any? {|p| p.id > 0 }
-      assert ! posts.any? {|p| p.id <= 0 }
+      assert posts.any? { |p| p.id > 0 }
+      assert ! posts.any? { |p| p.id <= 0 }
     end
 
     assert posts.loaded?
@@ -1238,8 +1095,8 @@ class RelationTest < ActiveRecord::TestCase
 
     assert_queries(2) do
       assert posts.many? # Uses COUNT()
-      assert posts.many? {|p| p.id > 0 }
-      assert ! posts.many? {|p| p.id < 2 }
+      assert posts.many? { |p| p.id > 0 }
+      assert ! posts.many? { |p| p.id < 2 }
     end
 
     assert posts.loaded?
@@ -1261,8 +1118,8 @@ class RelationTest < ActiveRecord::TestCase
     assert ! posts.loaded?
 
     assert_queries(1) do
-      assert posts.none? {|p| p.id < 0 }
-      assert ! posts.none? {|p| p.id == 1 }
+      assert posts.none? { |p| p.id < 0 }
+      assert ! posts.none? { |p| p.id == 1 }
     end
 
     assert posts.loaded?
@@ -1277,8 +1134,8 @@ class RelationTest < ActiveRecord::TestCase
     assert ! posts.loaded?
 
     assert_queries(1) do
-      assert ! posts.one? {|p| p.id < 3 }
-      assert posts.one? {|p| p.id == 1 }
+      assert ! posts.one? { |p| p.id < 3 }
+      assert posts.one? { |p| p.id == 1 }
     end
 
     assert posts.loaded?
@@ -1302,11 +1159,11 @@ class RelationTest < ActiveRecord::TestCase
   end
 
   def test_scoped_build
-    posts = Post.where(:title => 'You told a lie')
+    posts = Post.where(title: "You told a lie")
 
     post = posts.new
     assert_kind_of Post, post
-    assert_equal 'You told a lie', post.title
+    assert_equal "You told a lie", post.title
   end
 
   def test_create
@@ -1316,9 +1173,9 @@ class RelationTest < ActiveRecord::TestCase
     assert_kind_of Bird, sparrow
     assert !sparrow.persisted?
 
-    hen = birds.where(:name => 'hen').create
+    hen = birds.where(name: "hen").create
     assert hen.persisted?
-    assert_equal 'hen', hen.name
+    assert_equal "hen", hen.name
   end
 
   def test_create_bang
@@ -1326,201 +1183,210 @@ class RelationTest < ActiveRecord::TestCase
 
     assert_raises(ActiveRecord::RecordInvalid) { birds.create! }
 
-    hen = birds.where(:name => 'hen').create!
+    hen = birds.where(name: "hen").create!
     assert_kind_of Bird, hen
     assert hen.persisted?
-    assert_equal 'hen', hen.name
+    assert_equal "hen", hen.name
+  end
+
+  def test_create_with_polymorphic_association
+    author = authors(:david)
+    post = posts(:welcome)
+    comment = Comment.where(post: post, author: author).create!(body: "hello")
+
+    assert_equal author, comment.author
+    assert_equal post, comment.post
   end
 
   def test_first_or_create
-    parrot = Bird.where(:color => 'green').first_or_create(:name => 'parrot')
+    parrot = Bird.where(color: "green").first_or_create(name: "parrot")
     assert_kind_of Bird, parrot
     assert parrot.persisted?
-    assert_equal 'parrot', parrot.name
-    assert_equal 'green', parrot.color
+    assert_equal "parrot", parrot.name
+    assert_equal "green", parrot.color
 
-    same_parrot = Bird.where(:color => 'green').first_or_create(:name => 'parakeet')
+    same_parrot = Bird.where(color: "green").first_or_create(name: "parakeet")
     assert_kind_of Bird, same_parrot
     assert same_parrot.persisted?
     assert_equal parrot, same_parrot
   end
 
   def test_first_or_create_with_no_parameters
-    parrot = Bird.where(:color => 'green').first_or_create
+    parrot = Bird.where(color: "green").first_or_create
     assert_kind_of Bird, parrot
     assert !parrot.persisted?
-    assert_equal 'green', parrot.color
+    assert_equal "green", parrot.color
   end
 
   def test_first_or_create_with_block
-    parrot = Bird.where(:color => 'green').first_or_create { |bird| bird.name = 'parrot' }
+    parrot = Bird.where(color: "green").first_or_create { |bird| bird.name = "parrot" }
     assert_kind_of Bird, parrot
     assert parrot.persisted?
-    assert_equal 'green', parrot.color
-    assert_equal 'parrot', parrot.name
+    assert_equal "green", parrot.color
+    assert_equal "parrot", parrot.name
 
-    same_parrot = Bird.where(:color => 'green').first_or_create { |bird| bird.name = 'parakeet' }
+    same_parrot = Bird.where(color: "green").first_or_create { |bird| bird.name = "parakeet" }
     assert_equal parrot, same_parrot
   end
 
   def test_first_or_create_with_array
-    several_green_birds = Bird.where(:color => 'green').first_or_create([{:name => 'parrot'}, {:name => 'parakeet'}])
+    several_green_birds = Bird.where(color: "green").first_or_create([{ name: "parrot" }, { name: "parakeet" }])
     assert_kind_of Array, several_green_birds
     several_green_birds.each { |bird| assert bird.persisted? }
 
-    same_parrot = Bird.where(:color => 'green').first_or_create([{:name => 'hummingbird'}, {:name => 'macaw'}])
+    same_parrot = Bird.where(color: "green").first_or_create([{ name: "hummingbird" }, { name: "macaw" }])
     assert_kind_of Bird, same_parrot
     assert_equal several_green_birds.first, same_parrot
   end
 
   def test_first_or_create_bang_with_valid_options
-    parrot = Bird.where(:color => 'green').first_or_create!(:name => 'parrot')
+    parrot = Bird.where(color: "green").first_or_create!(name: "parrot")
     assert_kind_of Bird, parrot
     assert parrot.persisted?
-    assert_equal 'parrot', parrot.name
-    assert_equal 'green', parrot.color
+    assert_equal "parrot", parrot.name
+    assert_equal "green", parrot.color
 
-    same_parrot = Bird.where(:color => 'green').first_or_create!(:name => 'parakeet')
+    same_parrot = Bird.where(color: "green").first_or_create!(name: "parakeet")
     assert_kind_of Bird, same_parrot
     assert same_parrot.persisted?
     assert_equal parrot, same_parrot
   end
 
   def test_first_or_create_bang_with_invalid_options
-    assert_raises(ActiveRecord::RecordInvalid) { Bird.where(:color => 'green').first_or_create!(:pirate_id => 1) }
+    assert_raises(ActiveRecord::RecordInvalid) { Bird.where(color: "green").first_or_create!(pirate_id: 1) }
   end
 
   def test_first_or_create_bang_with_no_parameters
-    assert_raises(ActiveRecord::RecordInvalid) { Bird.where(:color => 'green').first_or_create! }
+    assert_raises(ActiveRecord::RecordInvalid) { Bird.where(color: "green").first_or_create! }
   end
 
   def test_first_or_create_bang_with_valid_block
-    parrot = Bird.where(:color => 'green').first_or_create! { |bird| bird.name = 'parrot' }
+    parrot = Bird.where(color: "green").first_or_create! { |bird| bird.name = "parrot" }
     assert_kind_of Bird, parrot
     assert parrot.persisted?
-    assert_equal 'green', parrot.color
-    assert_equal 'parrot', parrot.name
+    assert_equal "green", parrot.color
+    assert_equal "parrot", parrot.name
 
-    same_parrot = Bird.where(:color => 'green').first_or_create! { |bird| bird.name = 'parakeet' }
+    same_parrot = Bird.where(color: "green").first_or_create! { |bird| bird.name = "parakeet" }
     assert_equal parrot, same_parrot
   end
 
   def test_first_or_create_bang_with_invalid_block
     assert_raise(ActiveRecord::RecordInvalid) do
-      Bird.where(:color => 'green').first_or_create! { |bird| bird.pirate_id = 1 }
+      Bird.where(color: "green").first_or_create! { |bird| bird.pirate_id = 1 }
     end
   end
 
   def test_first_or_create_with_valid_array
-    several_green_birds = Bird.where(:color => 'green').first_or_create!([{:name => 'parrot'}, {:name => 'parakeet'}])
+    several_green_birds = Bird.where(color: "green").first_or_create!([{ name: "parrot" }, { name: "parakeet" }])
     assert_kind_of Array, several_green_birds
     several_green_birds.each { |bird| assert bird.persisted? }
 
-    same_parrot = Bird.where(:color => 'green').first_or_create!([{:name => 'hummingbird'}, {:name => 'macaw'}])
+    same_parrot = Bird.where(color: "green").first_or_create!([{ name: "hummingbird" }, { name: "macaw" }])
     assert_kind_of Bird, same_parrot
     assert_equal several_green_birds.first, same_parrot
   end
 
   def test_first_or_create_with_invalid_array
-    assert_raises(ActiveRecord::RecordInvalid) { Bird.where(:color => 'green').first_or_create!([ {:name => 'parrot'}, {:pirate_id => 1} ]) }
+    assert_raises(ActiveRecord::RecordInvalid) { Bird.where(color: "green").first_or_create!([ { name: "parrot" }, { pirate_id: 1 } ]) }
   end
 
   def test_first_or_initialize
-    parrot = Bird.where(:color => 'green').first_or_initialize(:name => 'parrot')
+    parrot = Bird.where(color: "green").first_or_initialize(name: "parrot")
     assert_kind_of Bird, parrot
     assert !parrot.persisted?
     assert parrot.valid?
     assert parrot.new_record?
-    assert_equal 'parrot', parrot.name
-    assert_equal 'green', parrot.color
+    assert_equal "parrot", parrot.name
+    assert_equal "green", parrot.color
   end
 
   def test_first_or_initialize_with_no_parameters
-    parrot = Bird.where(:color => 'green').first_or_initialize
+    parrot = Bird.where(color: "green").first_or_initialize
     assert_kind_of Bird, parrot
     assert !parrot.persisted?
     assert !parrot.valid?
     assert parrot.new_record?
-    assert_equal 'green', parrot.color
+    assert_equal "green", parrot.color
   end
 
   def test_first_or_initialize_with_block
-    parrot = Bird.where(:color => 'green').first_or_initialize { |bird| bird.name = 'parrot' }
+    parrot = Bird.where(color: "green").first_or_initialize { |bird| bird.name = "parrot" }
     assert_kind_of Bird, parrot
     assert !parrot.persisted?
     assert parrot.valid?
     assert parrot.new_record?
-    assert_equal 'green', parrot.color
-    assert_equal 'parrot', parrot.name
+    assert_equal "green", parrot.color
+    assert_equal "parrot", parrot.name
   end
 
   def test_find_or_create_by
-    assert_nil Bird.find_by(name: 'bob')
+    assert_nil Bird.find_by(name: "bob")
 
-    bird = Bird.find_or_create_by(name: 'bob')
+    bird = Bird.find_or_create_by(name: "bob")
     assert bird.persisted?
 
-    assert_equal bird, Bird.find_or_create_by(name: 'bob')
+    assert_equal bird, Bird.find_or_create_by(name: "bob")
   end
 
   def test_find_or_create_by_with_create_with
-    assert_nil Bird.find_by(name: 'bob')
+    assert_nil Bird.find_by(name: "bob")
 
-    bird = Bird.create_with(color: 'green').find_or_create_by(name: 'bob')
+    bird = Bird.create_with(color: "green").find_or_create_by(name: "bob")
     assert bird.persisted?
-    assert_equal 'green', bird.color
+    assert_equal "green", bird.color
 
-    assert_equal bird, Bird.create_with(color: 'blue').find_or_create_by(name: 'bob')
+    assert_equal bird, Bird.create_with(color: "blue").find_or_create_by(name: "bob")
   end
 
   def test_find_or_create_by!
-    assert_raises(ActiveRecord::RecordInvalid) { Bird.find_or_create_by!(color: 'green') }
+    assert_raises(ActiveRecord::RecordInvalid) { Bird.find_or_create_by!(color: "green") }
   end
 
   def test_find_or_initialize_by
-    assert_nil Bird.find_by(name: 'bob')
+    assert_nil Bird.find_by(name: "bob")
 
-    bird = Bird.find_or_initialize_by(name: 'bob')
+    bird = Bird.find_or_initialize_by(name: "bob")
     assert bird.new_record?
     bird.save!
 
-    assert_equal bird, Bird.find_or_initialize_by(name: 'bob')
+    assert_equal bird, Bird.find_or_initialize_by(name: "bob")
   end
 
-  def test_explicit_create_scope
-    hens = Bird.where(:name => 'hen')
-    assert_equal 'hen', hens.new.name
+  def test_explicit_create_with
+    hens = Bird.where(name: "hen")
+    assert_equal "hen", hens.new.name
 
-    hens = hens.create_with(:name => 'cock')
-    assert_equal 'cock', hens.new.name
+    hens = hens.create_with(name: "cock")
+    assert_equal "cock", hens.new.name
   end
 
   def test_except
-    relation = Post.where(:author_id => 1).order('id ASC').limit(1)
+    relation = Post.where(author_id: 1).order("id ASC").limit(1)
     assert_equal [posts(:welcome)], relation.to_a
 
     author_posts = relation.except(:order, :limit)
-    assert_equal Post.where(:author_id => 1).to_a, author_posts.to_a
+    assert_equal Post.where(author_id: 1).to_a, author_posts.to_a
 
     all_posts = relation.except(:where, :order, :limit)
     assert_equal Post.all, all_posts
   end
 
   def test_only
-    relation = Post.where(:author_id => 1).order('id ASC').limit(1)
+    relation = Post.where(author_id: 1).order("id ASC").limit(1)
     assert_equal [posts(:welcome)], relation.to_a
 
     author_posts = relation.only(:where)
-    assert_equal Post.where(:author_id => 1).to_a, author_posts.to_a
+    assert_equal Post.where(author_id: 1).to_a, author_posts.to_a
 
     all_posts = relation.only(:limit)
-    assert_equal Post.limit(1).to_a.first, all_posts.first
+    assert_equal Post.limit(1).to_a, all_posts.to_a
   end
 
   def test_anonymous_extension
-    relation = Post.where(:author_id => 1).order('id ASC').extending do
+    relation = Post.where(author_id: 1).order("id ASC").extending do
       def author
-        'lifo'
+        "lifo"
       end
     end
 
@@ -1529,7 +1395,7 @@ class RelationTest < ActiveRecord::TestCase
   end
 
   def test_named_extension
-    relation = Post.where(:author_id => 1).order('id ASC').extending(Post::NamedExtension)
+    relation = Post.where(author_id: 1).order("id ASC").extending(Post::NamedExtension)
     assert_equal "lifo", relation.author
     assert_equal "lifo", relation.limit(1).author
   end
@@ -1539,29 +1405,29 @@ class RelationTest < ActiveRecord::TestCase
   end
 
   def test_default_scope_order_with_scope_order
-    assert_equal 'zyke', CoolCar.order_using_new_style.limit(1).first.name
-    assert_equal 'zyke', FastCar.order_using_new_style.limit(1).first.name
+    assert_equal "zyke", CoolCar.order_using_new_style.limit(1).first.name
+    assert_equal "zyke", FastCar.order_using_new_style.limit(1).first.name
   end
 
   def test_order_using_scoping
-    car1 = CoolCar.order('id DESC').scoping do
-      CoolCar.all.merge!(order: 'id asc').first
+    car1 = CoolCar.order("id DESC").scoping do
+      CoolCar.all.merge!(order: "id asc").first
     end
-    assert_equal 'zyke', car1.name
+    assert_equal "zyke", car1.name
 
-    car2 = FastCar.order('id DESC').scoping do
-      FastCar.all.merge!(order: 'id asc').first
+    car2 = FastCar.order("id DESC").scoping do
+      FastCar.all.merge!(order: "id asc").first
     end
-    assert_equal 'zyke', car2.name
+    assert_equal "zyke", car2.name
   end
 
   def test_unscoped_block_style
-    assert_equal 'honda', CoolCar.unscoped { CoolCar.order_using_new_style.limit(1).first.name}
-    assert_equal 'honda', FastCar.unscoped { FastCar.order_using_new_style.limit(1).first.name}
+    assert_equal "honda", CoolCar.unscoped { CoolCar.order_using_new_style.limit(1).first.name }
+    assert_equal "honda", FastCar.unscoped { FastCar.order_using_new_style.limit(1).first.name }
   end
 
   def test_intersection_with_array
-    relation = Author.where(:name => "David")
+    relation = Author.where(name: "David")
     rails_author = relation.first
 
     assert_equal [rails_author], [rails_author] & relation
@@ -1573,7 +1439,7 @@ class RelationTest < ActiveRecord::TestCase
   end
 
   def test_ordering_with_extra_spaces
-    assert_equal authors(:david), Author.order('id DESC , name DESC').last
+    assert_equal authors(:david), Author.order("id DESC , name DESC").last
   end
 
   def test_update_all_with_blank_argument
@@ -1581,87 +1447,81 @@ class RelationTest < ActiveRecord::TestCase
   end
 
   def test_update_all_with_joins
-    comments = Comment.joins(:post).where('posts.id' => posts(:welcome).id)
+    comments = Comment.joins(:post).where("posts.id" => posts(:welcome).id)
     count    = comments.count
 
-    assert_equal count, comments.update_all(:post_id => posts(:thinking).id)
+    assert_equal count, comments.update_all(post_id: posts(:thinking).id)
     assert_equal posts(:thinking), comments(:greetings).post
   end
 
   def test_update_all_with_joins_and_limit
-    comments = Comment.joins(:post).where('posts.id' => posts(:welcome).id).limit(1)
-    assert_equal 1, comments.update_all(:post_id => posts(:thinking).id)
+    comments = Comment.joins(:post).where("posts.id" => posts(:welcome).id).limit(1)
+    assert_equal 1, comments.update_all(post_id: posts(:thinking).id)
   end
 
   def test_update_all_with_joins_and_limit_and_order
-    comments = Comment.joins(:post).where('posts.id' => posts(:welcome).id).order('comments.id').limit(1)
-    assert_equal 1, comments.update_all(:post_id => posts(:thinking).id)
+    comments = Comment.joins(:post).where("posts.id" => posts(:welcome).id).order("comments.id").limit(1)
+    assert_equal 1, comments.update_all(post_id: posts(:thinking).id)
     assert_equal posts(:thinking), comments(:greetings).post
     assert_equal posts(:welcome),  comments(:more_greetings).post
   end
 
   def test_update_all_with_joins_and_offset
-    all_comments = Comment.joins(:post).where('posts.id' => posts(:welcome).id)
+    all_comments = Comment.joins(:post).where("posts.id" => posts(:welcome).id)
     count        = all_comments.count
     comments     = all_comments.offset(1)
 
-    assert_equal count - 1, comments.update_all(:post_id => posts(:thinking).id)
+    assert_equal count - 1, comments.update_all(post_id: posts(:thinking).id)
   end
 
   def test_update_all_with_joins_and_offset_and_order
-    all_comments = Comment.joins(:post).where('posts.id' => posts(:welcome).id).order('posts.id', 'comments.id')
+    all_comments = Comment.joins(:post).where("posts.id" => posts(:welcome).id).order("posts.id", "comments.id")
     count        = all_comments.count
     comments     = all_comments.offset(1)
 
-    assert_equal count - 1, comments.update_all(:post_id => posts(:thinking).id)
+    assert_equal count - 1, comments.update_all(post_id: posts(:thinking).id)
     assert_equal posts(:thinking), comments(:more_greetings).post
     assert_equal posts(:welcome),  comments(:greetings).post
   end
 
   def test_update_on_relation
-    topic1 = TopicWithCallbacks.create! title: 'arel', author_name: nil
-    topic2 = TopicWithCallbacks.create! title: 'activerecord', author_name: nil
+    topic1 = TopicWithCallbacks.create! title: "arel", author_name: nil
+    topic2 = TopicWithCallbacks.create! title: "activerecord", author_name: nil
     topics = TopicWithCallbacks.where(id: [topic1.id, topic2.id])
-    topics.update(title: 'adequaterecord')
+    topics.update(title: "adequaterecord")
 
-    assert_equal 'adequaterecord', topic1.reload.title
-    assert_equal 'adequaterecord', topic2.reload.title
+    assert_equal "adequaterecord", topic1.reload.title
+    assert_equal "adequaterecord", topic2.reload.title
     # Testing that the before_update callbacks have run
-    assert_equal 'David', topic1.reload.author_name
-    assert_equal 'David', topic2.reload.author_name
+    assert_equal "David", topic1.reload.author_name
+    assert_equal "David", topic2.reload.author_name
   end
 
-  def test_update_on_relation_passing_active_record_object_is_deprecated
-    topic = Topic.create!(title: 'Foo', author_name: nil)
-    assert_deprecated(/update/) do
-      Topic.where(id: topic.id).update(topic, title: 'Bar')
+  def test_update_on_relation_passing_active_record_object_is_not_permitted
+    topic = Topic.create!(title: "Foo", author_name: nil)
+    assert_raises(ArgumentError) do
+      Topic.where(id: topic.id).update(topic, title: "Bar")
     end
   end
 
   def test_distinct
-    tag1 = Tag.create(:name => 'Foo')
-    tag2 = Tag.create(:name => 'Foo')
+    tag1 = Tag.create(name: "Foo")
+    tag2 = Tag.create(name: "Foo")
 
-    query = Tag.select(:name).where(:id => [tag1.id, tag2.id])
+    query = Tag.select(:name).where(id: [tag1.id, tag2.id])
 
-    assert_equal ['Foo', 'Foo'], query.map(&:name)
+    assert_equal ["Foo", "Foo"], query.map(&:name)
     assert_sql(/DISTINCT/) do
-      assert_equal ['Foo'], query.distinct.map(&:name)
-      assert_deprecated { assert_equal ['Foo'], query.uniq.map(&:name) }
+      assert_equal ["Foo"], query.distinct.map(&:name)
     end
     assert_sql(/DISTINCT/) do
-      assert_equal ['Foo'], query.distinct(true).map(&:name)
-      assert_deprecated { assert_equal ['Foo'], query.uniq(true).map(&:name) }
-    end
-    assert_equal ['Foo', 'Foo'], query.distinct(true).distinct(false).map(&:name)
-
-    assert_deprecated do
-      assert_equal ['Foo', 'Foo'], query.uniq(true).uniq(false).map(&:name)
+      assert_equal ["Foo"], query.distinct(true).map(&:name)
     end
+    assert_equal ["Foo", "Foo"], query.distinct(true).distinct(false).map(&:name)
   end
 
   def test_doesnt_add_having_values_if_options_are_blank
-    scope = Post.having('')
+    scope = Post.having("")
     assert scope.having_clause.empty?
 
     scope = Post.having([])
@@ -1701,62 +1561,76 @@ class RelationTest < ActiveRecord::TestCase
   end
 
   def test_automatically_added_where_references
-    scope = Post.where(:comments => { :body => "Bla" })
-    assert_equal ['comments'], scope.references_values
+    scope = Post.where(comments: { body: "Bla" })
+    assert_equal ["comments"], scope.references_values
 
-    scope = Post.where('comments.body' => 'Bla')
-    assert_equal ['comments'], scope.references_values
+    scope = Post.where("comments.body" => "Bla")
+    assert_equal ["comments"], scope.references_values
   end
 
   def test_automatically_added_where_not_references
     scope = Post.where.not(comments: { body: "Bla" })
-    assert_equal ['comments'], scope.references_values
+    assert_equal ["comments"], scope.references_values
 
-    scope = Post.where.not('comments.body' => 'Bla')
-    assert_equal ['comments'], scope.references_values
+    scope = Post.where.not("comments.body" => "Bla")
+    assert_equal ["comments"], scope.references_values
   end
 
   def test_automatically_added_having_references
-    scope = Post.having(:comments => { :body => "Bla" })
-    assert_equal ['comments'], scope.references_values
+    scope = Post.having(comments: { body: "Bla" })
+    assert_equal ["comments"], scope.references_values
 
-    scope = Post.having('comments.body' => 'Bla')
-    assert_equal ['comments'], scope.references_values
+    scope = Post.having("comments.body" => "Bla")
+    assert_equal ["comments"], scope.references_values
   end
 
   def test_automatically_added_order_references
-    scope = Post.order('comments.body')
-    assert_equal ['comments'], scope.references_values
+    scope = Post.order("comments.body")
+    assert_equal ["comments"], scope.references_values
+
+    scope = Post.order(Arel.sql("#{Comment.quoted_table_name}.#{Comment.quoted_primary_key}"))
+    if current_adapter?(:OracleAdapter)
+      assert_equal ["COMMENTS"], scope.references_values
+    else
+      assert_equal ["comments"], scope.references_values
+    end
 
-    scope = Post.order('comments.body', 'yaks.body')
-    assert_equal ['comments', 'yaks'], scope.references_values
+    scope = Post.order("comments.body", "yaks.body")
+    assert_equal ["comments", "yaks"], scope.references_values
 
     # Don't infer yaks, let's not go down that road again...
-    scope = Post.order('comments.body, yaks.body')
-    assert_equal ['comments'], scope.references_values
+    scope = Post.order("comments.body, yaks.body")
+    assert_equal ["comments"], scope.references_values
 
-    scope = Post.order('comments.body asc')
-    assert_equal ['comments'], scope.references_values
+    scope = Post.order("comments.body asc")
+    assert_equal ["comments"], scope.references_values
 
-    scope = Post.order('foo(comments.body)')
+    scope = Post.order(Arel.sql("foo(comments.body)"))
     assert_equal [], scope.references_values
   end
 
   def test_automatically_added_reorder_references
-    scope = Post.reorder('comments.body')
+    scope = Post.reorder("comments.body")
     assert_equal %w(comments), scope.references_values
 
-    scope = Post.reorder('comments.body', 'yaks.body')
+    scope = Post.reorder(Arel.sql("#{Comment.quoted_table_name}.#{Comment.quoted_primary_key}"))
+    if current_adapter?(:OracleAdapter)
+      assert_equal ["COMMENTS"], scope.references_values
+    else
+      assert_equal ["comments"], scope.references_values
+    end
+
+    scope = Post.reorder("comments.body", "yaks.body")
     assert_equal %w(comments yaks), scope.references_values
 
     # Don't infer yaks, let's not go down that road again...
-    scope = Post.reorder('comments.body, yaks.body')
+    scope = Post.reorder("comments.body, yaks.body")
     assert_equal %w(comments), scope.references_values
 
-    scope = Post.reorder('comments.body asc')
+    scope = Post.reorder("comments.body asc")
     assert_equal %w(comments), scope.references_values
 
-    scope = Post.reorder('foo(comments.body)')
+    scope = Post.reorder(Arel.sql("foo(comments.body)"))
     assert_equal [], scope.references_values
   end
 
@@ -1803,11 +1677,11 @@ class RelationTest < ActiveRecord::TestCase
   end
 
   test "find_by with multi-arg conditions returns the first matching record" do
-    assert_equal posts(:eager_other), Post.order(:id).find_by('author_id = ?', 2)
+    assert_equal posts(:eager_other), Post.order(:id).find_by("author_id = ?", 2)
   end
 
   test "find_by returns nil if the record is missing" do
-    assert_equal nil, Post.all.find_by("1 = 0")
+    assert_nil Post.all.find_by("1 = 0")
   end
 
   test "find_by doesn't have implicit ordering" do
@@ -1827,7 +1701,7 @@ class RelationTest < ActiveRecord::TestCase
   end
 
   test "find_by! with multi-arg conditions returns the first matching record" do
-    assert_equal posts(:eager_other), Post.order(:id).find_by!('author_id = ?', 2)
+    assert_equal posts(:eager_other), Post.order(:id).find_by!("author_id = ?", 2)
   end
 
   test "find_by! doesn't have implicit ordering" do
@@ -1849,7 +1723,7 @@ class RelationTest < ActiveRecord::TestCase
     relation.to_a
 
     assert_raises(ActiveRecord::ImmutableRelation) do
-      relation.where! 'foo'
+      relation.where! "foo"
     end
   end
 
@@ -1867,7 +1741,7 @@ class RelationTest < ActiveRecord::TestCase
     relation.to_a
 
     assert_raises(ActiveRecord::ImmutableRelation) do
-      relation.merge! where: 'foo'
+      relation.merge! where: "foo"
     end
   end
 
@@ -1882,7 +1756,7 @@ class RelationTest < ActiveRecord::TestCase
 
   test "relations with cached arel can't be mutated [internal API]" do
     relation = Post.all
-    relation.count
+    relation.arel
 
     assert_raises(ActiveRecord::ImmutableRelation) { relation.limit!(5) }
     assert_raises(ActiveRecord::ImmutableRelation) { relation.where!("1 = 2") }
@@ -1898,6 +1772,12 @@ class RelationTest < ActiveRecord::TestCase
     assert_equal "#<ActiveRecord::Relation [#{Post.limit(10).map(&:inspect).join(', ')}, ...]>", relation.inspect
   end
 
+  test "relations don't load all records in #inspect" do
+    assert_sql(/LIMIT|ROWNUM <=|FETCH FIRST/) do
+      Post.all.inspect
+    end
+  end
+
   test "already-loaded relations don't perform a new query in #inspect" do
     relation = Post.limit(2)
     relation.to_a
@@ -1909,19 +1789,27 @@ class RelationTest < ActiveRecord::TestCase
     end
   end
 
-  test 'using a custom table affects the wheres' do
-    table_alias = Post.arel_table.alias('omg_posts')
+  test "using a custom table affects the wheres" do
+    post = posts(:welcome)
 
-    table_metadata = ActiveRecord::TableMetadata.new(Post, table_alias)
-    predicate_builder = ActiveRecord::PredicateBuilder.new(table_metadata)
-    relation = ActiveRecord::Relation.new(Post, table_alias, predicate_builder)
-    relation.where!(:foo => "bar")
+    assert_equal post, custom_post_relation.where!(title: post.title).take
+  end
 
-    node = relation.arel.constraints.first.grep(Arel::Attributes::Attribute).first
-    assert_equal table_alias, node.relation
+  test "using a custom table with joins affects the joins" do
+    post = posts(:welcome)
+
+    assert_equal post, custom_post_relation.joins(:author).where!(title: post.title).take
+  end
+
+  test "arel_attribute respects a custom table" do
+    assert_equal [posts(:sti_comments)], custom_post_relation.ranked_by_comments.limit_by(1).to_a
   end
 
-  test '#load' do
+  test "alias_tracker respects a custom table" do
+    assert_equal posts(:welcome), custom_post_relation("categories_posts").joins(:categories).first
+  end
+
+  test "#load" do
     relation = Post.all
     assert_queries(1) do
       assert_equal relation, relation.load
@@ -1929,9 +1817,9 @@ class RelationTest < ActiveRecord::TestCase
     assert_no_queries { relation.to_a }
   end
 
-  test 'group with select and includes' do
-    authors_count = Post.select('author_id, COUNT(author_id) AS num_posts').
-      group('author_id').order('author_id').includes(:author).to_a
+  test "group with select and includes" do
+    authors_count = Post.select("author_id, COUNT(author_id) AS num_posts").
+      group("author_id").order("author_id").includes(:author).to_a
 
     assert_no_queries do
       result = authors_count.map do |post|
@@ -1955,61 +1843,97 @@ class RelationTest < ActiveRecord::TestCase
     assert !Post.all.respond_to?(:by_lifo)
   end
 
-  def test_unscope_removes_binds
-    left  = Post.where(id: Arel::Nodes::BindParam.new)
-    column = Post.columns_hash['id']
-    left.bind_values += [[column, 20]]
+  def test_unscope_with_subquery
+    p1 = Post.where(id: 1)
+    p2 = Post.where(id: 2)
 
-    relation = left.unscope(where: :id)
-    assert_equal [], relation.bind_values
-  end
+    assert_not_equal p1, p2
 
-  def test_merging_removes_rhs_bind_parameters
-    left  = Post.where(id: 20)
-    right   = Post.where(id: [1,2,3,4])
+    comments = Comment.where(post: p1).unscope(where: :post_id).where(post: p2)
 
-    merged = left.merge(right)
-    assert_equal [], merged.bind_values
+    assert_not_equal p1.first.comments, comments
+    assert_equal p2.first.comments, comments
   end
 
-  def test_merging_keeps_lhs_bind_parameters
-    binds = [ActiveRecord::Relation::QueryAttribute.new("id", 20, Post.type_for_attribute("id"))]
+  def test_unscope_specific_where_value
+    posts = Post.where(title: "Welcome to the weblog", body: "Such a lovely day")
 
-    right  = Post.where(id: 20)
-    left   = Post.where(id: 10)
-
-    merged = left.merge(right)
-    assert_equal binds, merged.bound_attributes
+    assert_equal 1, posts.count
+    assert_equal 1, posts.unscope(where: :title).count
+    assert_equal 1, posts.unscope(where: :body).count
   end
 
-  def test_merging_reorders_bind_params
-    post  = Post.first
-    right = Post.where(id: post.id)
-    left  = Post.where(title: post.title)
-
-    merged = left.merge(right)
-    assert_equal post, merged.first
+  def test_locked_should_not_build_arel
+    posts = Post.locked
+    assert posts.locked?
+    assert_nothing_raised { posts.lock!(false) }
   end
 
   def test_relation_join_method
-    assert_equal 'Thank you for the welcome,Thank you again for the welcome', Post.first.comments.join(",")
+    assert_equal "Thank you for the welcome,Thank you again for the welcome", Post.first.comments.join(",")
   end
 
-  def test_connection_adapters_can_reorder_binds
-    posts = Post.limit(1).offset(2)
+  test "#skip_query_cache!" do
+    Post.cache do
+      assert_queries(1) do
+        Post.all.load
+        Post.all.load
+      end
 
-    stubbed_connection = Post.connection.dup
-    def stubbed_connection.combine_bind_parameters(**kwargs)
-      offset = kwargs[:offset]
-      kwargs[:offset] = kwargs[:limit]
-      kwargs[:limit] = offset
-      super(**kwargs)
+      assert_queries(2) do
+        Post.all.skip_query_cache!.load
+        Post.all.skip_query_cache!.load
+      end
     end
+  end
 
-    posts.define_singleton_method(:connection) do
-      stubbed_connection
+  test "#skip_query_cache! with an eager load" do
+    Post.cache do
+      assert_queries(1) do
+        Post.eager_load(:comments).load
+        Post.eager_load(:comments).load
+      end
+
+      assert_queries(2) do
+        Post.eager_load(:comments).skip_query_cache!.load
+        Post.eager_load(:comments).skip_query_cache!.load
+      end
+    end
+  end
+
+  test "#skip_query_cache! with a preload" do
+    Post.cache do
+      assert_queries(2) do
+        Post.preload(:comments).load
+        Post.preload(:comments).load
+      end
+
+      assert_queries(4) do
+        Post.preload(:comments).skip_query_cache!.load
+        Post.preload(:comments).skip_query_cache!.load
+      end
     end
+  end
+
+  test "#where with set" do
+    david = authors(:david)
+    mary = authors(:mary)
+
+    authors = Author.where(name: ["David", "Mary"].to_set)
+    assert_equal [david, mary], authors
+  end
 
-    assert_equal 2, posts.to_a.length
+  test "#where with empty set" do
+    authors = Author.where(name: Set.new)
+    assert_empty authors
   end
+
+  private
+    def custom_post_relation(alias_name = "omg_posts")
+      table_alias = Post.arel_table.alias(alias_name)
+      table_metadata = ActiveRecord::TableMetadata.new(Post, table_alias)
+      predicate_builder = ActiveRecord::PredicateBuilder.new(table_metadata)
+
+      ActiveRecord::Relation.create(Post, table_alias, predicate_builder)
+    end
 end
diff --git a/activerecord/test/cases/reload_models_test.rb b/activerecord/test/cases/reload_models_test.rb
index 431fbf1297..72f4bfaf6d 100644
--- a/activerecord/test/cases/reload_models_test.rb
+++ b/activerecord/test/cases/reload_models_test.rb
@@ -1,22 +1,26 @@
+# frozen_string_literal: true
+
 require "cases/helper"
-require 'models/owner'
-require 'models/pet'
+require "models/owner"
+require "models/pet"
 
 class ReloadModelsTest < ActiveRecord::TestCase
+  include ActiveSupport::Testing::Isolation
+
   fixtures :pets, :owners
 
   def test_has_one_with_reload
-    pet = Pet.find_by_name('parrot')
-    pet.owner = Owner.find_by_name('ashley')
+    pet = Pet.find_by_name("parrot")
+    pet.owner = Owner.find_by_name("ashley")
 
     # Reload the class Owner, simulating auto-reloading of model classes in a
     # development environment. Note that meanwhile the class Pet is not
     # reloaded, simulating a class that is present in a plugin.
     Object.class_eval { remove_const :Owner }
-    Kernel.load(File.expand_path(File.join(File.dirname(__FILE__), "../models/owner.rb")))
+    Kernel.load(File.expand_path("../models/owner.rb", __dir__))
 
-    pet = Pet.find_by_name('parrot')
-    pet.owner = Owner.find_by_name('ashley')
-    assert_equal pet.owner, Owner.find_by_name('ashley')
+    pet = Pet.find_by_name("parrot")
+    pet.owner = Owner.find_by_name("ashley")
+    assert_equal pet.owner, Owner.find_by_name("ashley")
   end
-end
+end unless in_memory_db?
diff --git a/activerecord/test/cases/reserved_word_test.rb b/activerecord/test/cases/reserved_word_test.rb
new file mode 100644
index 0000000000..4f8ca392b9
--- /dev/null
+++ b/activerecord/test/cases/reserved_word_test.rb
@@ -0,0 +1,141 @@
+# frozen_string_literal: true
+
+require "cases/helper"
+
+class ReservedWordTest < ActiveRecord::TestCase
+  self.use_instantiated_fixtures = true
+  self.use_transactional_tests = false
+
+  class Group < ActiveRecord::Base
+    Group.table_name = "group"
+    belongs_to :select
+    has_one :values
+  end
+
+  class Select < ActiveRecord::Base
+    Select.table_name = "select"
+    has_many :groups
+  end
+
+  class Values < ActiveRecord::Base
+    Values.table_name = "values"
+  end
+
+  class Distinct < ActiveRecord::Base
+    Distinct.table_name = "distinct"
+    has_and_belongs_to_many :selects
+    has_many :values, through: :groups
+  end
+
+  def setup
+    @connection = ActiveRecord::Base.connection
+    @connection.create_table :select, force: true
+    @connection.create_table :distinct, force: true
+    @connection.create_table :distinct_select, id: false, force: true do |t|
+      t.belongs_to :distinct
+      t.belongs_to :select
+    end
+    @connection.create_table :group, force: true do |t|
+      t.string :order
+      t.belongs_to :select
+    end
+    @connection.create_table :values, primary_key: :as, force: true do |t|
+      t.belongs_to :group
+    end
+  end
+
+  def teardown
+    @connection.drop_table :select, if_exists: true
+    @connection.drop_table :distinct, if_exists: true
+    @connection.drop_table :distinct_select, if_exists: true
+    @connection.drop_table :group, if_exists: true
+    @connection.drop_table :values, if_exists: true
+    @connection.drop_table :order, if_exists: true
+  end
+
+  def test_create_tables
+    assert_not @connection.table_exists?(:order)
+
+    @connection.create_table :order do |t|
+      t.string :group
+    end
+
+    assert @connection.table_exists?(:order)
+  end
+
+  def test_rename_tables
+    assert_nothing_raised { @connection.rename_table(:group, :order) }
+  end
+
+  def test_change_columns
+    assert_nothing_raised { @connection.change_column_default(:group, :order, "whatever") }
+    assert_nothing_raised { @connection.change_column("group", "order", :text, default: nil) }
+    assert_nothing_raised { @connection.rename_column(:group, :order, :values) }
+  end
+
+  def test_introspect
+    assert_equal ["id", "order", "select_id"], @connection.columns(:group).map(&:name).sort
+    assert_equal ["index_group_on_select_id"], @connection.indexes(:group).map(&:name).sort
+  end
+
+  def test_activerecord_model
+    x = Group.new
+    x.order = "x"
+    x.save!
+    x.order = "y"
+    x.save!
+    assert_equal x, Group.find_by_order("y")
+    assert_equal x, Group.find(x.id)
+  end
+
+  def test_delete_all_with_subselect
+    create_test_fixtures :values
+    assert_equal 1, Values.order(:as).limit(1).offset(1).delete_all
+    assert_raise(ActiveRecord::RecordNotFound) { Values.find(2) }
+    assert Values.find(1)
+  end
+
+  def test_has_one_associations
+    create_test_fixtures :group, :values
+    v = Group.find(1).values
+    assert_equal 2, v.id
+  end
+
+  def test_belongs_to_associations
+    create_test_fixtures :select, :group
+    gs = Select.find(2).groups
+    assert_equal 2, gs.length
+    assert_equal [2, 3], gs.collect(&:id).sort
+  end
+
+  def test_has_and_belongs_to_many
+    create_test_fixtures :select, :distinct, :distinct_select
+    s = Distinct.find(1).selects
+    assert_equal 2, s.length
+    assert_equal [1, 2], s.collect(&:id).sort
+  end
+
+  def test_activerecord_introspection
+    assert Group.table_exists?
+    assert_equal ["id", "order", "select_id"], Group.columns.map(&:name).sort
+  end
+
+  def test_calculations_work_with_reserved_words
+    create_test_fixtures :group
+    assert_equal 3, Group.count
+  end
+
+  def test_associations_work_with_reserved_words
+    create_test_fixtures :select, :group
+    selects = Select.all.merge!(includes: [:groups]).to_a
+    assert_no_queries do
+      selects.each { |select| select.groups }
+    end
+  end
+
+  private
+    # custom fixture loader, uses FixtureSet#create_fixtures and appends base_path to the current file's path
+    def create_test_fixtures(*fixture_names)
+      ActiveRecord::FixtureSet.create_fixtures(FIXTURES_ROOT + "/reserved_words", fixture_names)
+    end
+end
diff --git a/activerecord/test/cases/result_test.rb b/activerecord/test/cases/result_test.rb
index dec01dfa76..db52c108ac 100644
--- a/activerecord/test/cases/result_test.rb
+++ b/activerecord/test/cases/result_test.rb
@@ -1,12 +1,14 @@
+# frozen_string_literal: true
+
 require "cases/helper"
 
 module ActiveRecord
   class ResultTest < ActiveRecord::TestCase
     def result
-      Result.new(['col_1', 'col_2'], [
-        ['row 1 col 1', 'row 1 col 2'],
-        ['row 2 col 1', 'row 2 col 2'],
-        ['row 3 col 1', 'row 3 col 2'],
+      Result.new(["col_1", "col_2"], [
+        ["row 1 col 1", "row 1 col 2"],
+        ["row 2 col 1", "row 2 col 2"],
+        ["row 3 col 1", "row 3 col 2"],
       ])
     end
 
@@ -16,29 +18,37 @@ module ActiveRecord
 
     test "to_hash returns row_hashes" do
       assert_equal [
-        {'col_1' => 'row 1 col 1', 'col_2' => 'row 1 col 2'},
-        {'col_1' => 'row 2 col 1', 'col_2' => 'row 2 col 2'},
-        {'col_1' => 'row 3 col 1', 'col_2' => 'row 3 col 2'},
+        { "col_1" => "row 1 col 1", "col_2" => "row 1 col 2" },
+        { "col_1" => "row 2 col 1", "col_2" => "row 2 col 2" },
+        { "col_1" => "row 3 col 1", "col_2" => "row 3 col 2" },
       ], result.to_hash
     end
 
+    test "first returns first row as a hash" do
+      assert_equal(
+        { "col_1" => "row 1 col 1", "col_2" => "row 1 col 2" }, result.first)
+    end
+
+    test "last returns last row as a hash" do
+      assert_equal(
+        { "col_1" => "row 3 col 1", "col_2" => "row 3 col 2" }, result.last)
+    end
+
     test "each with block returns row hashes" do
       result.each do |row|
-        assert_equal ['col_1', 'col_2'], row.keys
+        assert_equal ["col_1", "col_2"], row.keys
       end
     end
 
     test "each without block returns an enumerator" do
       result.each.with_index do |row, index|
-        assert_equal ['col_1', 'col_2'], row.keys
+        assert_equal ["col_1", "col_2"], row.keys
         assert_kind_of Integer, index
       end
     end
 
-    if Enumerator.method_defined? :size
-      test "each without block returns a sized enumerator" do
-        assert_equal 3, result.each.size
-      end
+    test "each without block returns a sized enumerator" do
+      assert_equal 3, result.each.size
     end
 
     test "cast_values returns rows after type casting" do
diff --git a/activerecord/test/cases/sanitize_test.rb b/activerecord/test/cases/sanitize_test.rb
index 239f63d27b..1b0605e369 100644
--- a/activerecord/test/cases/sanitize_test.rb
+++ b/activerecord/test/cases/sanitize_test.rb
@@ -1,7 +1,9 @@
+# frozen_string_literal: true
+
 require "cases/helper"
-require 'models/binary'
-require 'models/author'
-require 'models/post'
+require "models/binary"
+require "models/author"
+require "models/post"
 
 class SanitizeTest < ActiveRecord::TestCase
   def setup
@@ -9,97 +11,105 @@ class SanitizeTest < ActiveRecord::TestCase
 
   def test_sanitize_sql_array_handles_string_interpolation
     quoted_bambi = ActiveRecord::Base.connection.quote_string("Bambi")
-    assert_equal "name='#{quoted_bambi}'", Binary.send(:sanitize_sql_array, ["name='%s'", "Bambi"])
-    assert_equal "name='#{quoted_bambi}'", Binary.send(:sanitize_sql_array, ["name='%s'", "Bambi".mb_chars])
+    assert_equal "name='#{quoted_bambi}'", Binary.sanitize_sql_array(["name='%s'", "Bambi"])
+    assert_equal "name='#{quoted_bambi}'", Binary.sanitize_sql_array(["name='%s'", "Bambi".mb_chars])
     quoted_bambi_and_thumper = ActiveRecord::Base.connection.quote_string("Bambi\nand\nThumper")
-    assert_equal "name='#{quoted_bambi_and_thumper}'",Binary.send(:sanitize_sql_array, ["name='%s'", "Bambi\nand\nThumper"])
-    assert_equal "name='#{quoted_bambi_and_thumper}'",Binary.send(:sanitize_sql_array, ["name='%s'", "Bambi\nand\nThumper".mb_chars])
+    assert_equal "name='#{quoted_bambi_and_thumper}'", Binary.sanitize_sql_array(["name='%s'", "Bambi\nand\nThumper"])
+    assert_equal "name='#{quoted_bambi_and_thumper}'", Binary.sanitize_sql_array(["name='%s'", "Bambi\nand\nThumper".mb_chars])
   end
 
   def test_sanitize_sql_array_handles_bind_variables
     quoted_bambi = ActiveRecord::Base.connection.quote("Bambi")
-    assert_equal "name=#{quoted_bambi}", Binary.send(:sanitize_sql_array, ["name=?", "Bambi"])
-    assert_equal "name=#{quoted_bambi}", Binary.send(:sanitize_sql_array, ["name=?", "Bambi".mb_chars])
+    assert_equal "name=#{quoted_bambi}", Binary.sanitize_sql_array(["name=?", "Bambi"])
+    assert_equal "name=#{quoted_bambi}", Binary.sanitize_sql_array(["name=?", "Bambi".mb_chars])
     quoted_bambi_and_thumper = ActiveRecord::Base.connection.quote("Bambi\nand\nThumper")
-    assert_equal "name=#{quoted_bambi_and_thumper}", Binary.send(:sanitize_sql_array, ["name=?", "Bambi\nand\nThumper"])
-    assert_equal "name=#{quoted_bambi_and_thumper}", Binary.send(:sanitize_sql_array, ["name=?", "Bambi\nand\nThumper".mb_chars])
+    assert_equal "name=#{quoted_bambi_and_thumper}", Binary.sanitize_sql_array(["name=?", "Bambi\nand\nThumper"])
+    assert_equal "name=#{quoted_bambi_and_thumper}", Binary.sanitize_sql_array(["name=?", "Bambi\nand\nThumper".mb_chars])
   end
 
   def test_sanitize_sql_array_handles_named_bind_variables
     quoted_bambi = ActiveRecord::Base.connection.quote("Bambi")
-    assert_equal "name=#{quoted_bambi}", Binary.send(:sanitize_sql_array, ["name=:name", name: "Bambi"])
-    assert_equal "name=#{quoted_bambi} AND id=1", Binary.send(:sanitize_sql_array, ["name=:name AND id=:id", name: "Bambi", id: 1])
+    assert_equal "name=#{quoted_bambi}", Binary.sanitize_sql_array(["name=:name", name: "Bambi"])
+    assert_equal "name=#{quoted_bambi} AND id=1", Binary.sanitize_sql_array(["name=:name AND id=:id", name: "Bambi", id: 1])
 
     quoted_bambi_and_thumper = ActiveRecord::Base.connection.quote("Bambi\nand\nThumper")
-    assert_equal "name=#{quoted_bambi_and_thumper}", Binary.send(:sanitize_sql_array, ["name=:name", name: "Bambi\nand\nThumper"])
-    assert_equal "name=#{quoted_bambi_and_thumper} AND name2=#{quoted_bambi_and_thumper}", Binary.send(:sanitize_sql_array, ["name=:name AND name2=:name", name: "Bambi\nand\nThumper"])
+    assert_equal "name=#{quoted_bambi_and_thumper}", Binary.sanitize_sql_array(["name=:name", name: "Bambi\nand\nThumper"])
+    assert_equal "name=#{quoted_bambi_and_thumper} AND name2=#{quoted_bambi_and_thumper}", Binary.sanitize_sql_array(["name=:name AND name2=:name", name: "Bambi\nand\nThumper"])
   end
 
   def test_sanitize_sql_array_handles_relations
-    david = Author.create!(name: 'David')
+    david = Author.create!(name: "David")
     david_posts = david.posts.select(:id)
 
     sub_query_pattern = /\(\bselect\b.*?\bwhere\b.*?\)/i
 
-    select_author_sql = Post.send(:sanitize_sql_array, ['id in (?)', david_posts])
-    assert_match(sub_query_pattern, select_author_sql, 'should sanitize `Relation` as subquery for bind variables')
+    select_author_sql = Post.sanitize_sql_array(["id in (?)", david_posts])
+    assert_match(sub_query_pattern, select_author_sql, "should sanitize `Relation` as subquery for bind variables")
 
-    select_author_sql = Post.send(:sanitize_sql_array, ['id in (:post_ids)', post_ids: david_posts])
-    assert_match(sub_query_pattern, select_author_sql, 'should sanitize `Relation` as subquery for named bind variables')
+    select_author_sql = Post.sanitize_sql_array(["id in (:post_ids)", post_ids: david_posts])
+    assert_match(sub_query_pattern, select_author_sql, "should sanitize `Relation` as subquery for named bind variables")
   end
 
   def test_sanitize_sql_array_handles_empty_statement
-    select_author_sql = Post.send(:sanitize_sql_array, [''])
-    assert_equal('', select_author_sql)
+    select_author_sql = Post.sanitize_sql_array([""])
+    assert_equal("", select_author_sql)
   end
 
   def test_sanitize_sql_like
-    assert_equal '100\%', Binary.send(:sanitize_sql_like, '100%')
-    assert_equal 'snake\_cased\_string', Binary.send(:sanitize_sql_like, 'snake_cased_string')
-    assert_equal 'C:\\\\Programs\\\\MsPaint', Binary.send(:sanitize_sql_like, 'C:\\Programs\\MsPaint')
-    assert_equal 'normal string 42', Binary.send(:sanitize_sql_like, 'normal string 42')
+    assert_equal '100\%', Binary.sanitize_sql_like("100%")
+    assert_equal 'snake\_cased\_string', Binary.sanitize_sql_like("snake_cased_string")
+    assert_equal 'C:\\\\Programs\\\\MsPaint', Binary.sanitize_sql_like('C:\\Programs\\MsPaint')
+    assert_equal "normal string 42", Binary.sanitize_sql_like("normal string 42")
   end
 
   def test_sanitize_sql_like_with_custom_escape_character
-    assert_equal '100!%', Binary.send(:sanitize_sql_like, '100%', '!')
-    assert_equal 'snake!_cased!_string', Binary.send(:sanitize_sql_like, 'snake_cased_string', '!')
-    assert_equal 'great!!', Binary.send(:sanitize_sql_like, 'great!', '!')
-    assert_equal 'C:\\Programs\\MsPaint', Binary.send(:sanitize_sql_like, 'C:\\Programs\\MsPaint', '!')
-    assert_equal 'normal string 42', Binary.send(:sanitize_sql_like, 'normal string 42', '!')
+    assert_equal "100!%", Binary.sanitize_sql_like("100%", "!")
+    assert_equal "snake!_cased!_string", Binary.sanitize_sql_like("snake_cased_string", "!")
+    assert_equal "great!!", Binary.sanitize_sql_like("great!", "!")
+    assert_equal 'C:\\Programs\\MsPaint', Binary.sanitize_sql_like('C:\\Programs\\MsPaint', "!")
+    assert_equal "normal string 42", Binary.sanitize_sql_like("normal string 42", "!")
   end
 
   def test_sanitize_sql_like_example_use_case
     searchable_post = Class.new(Post) do
-      def self.search(term)
-        where("title LIKE ?", sanitize_sql_like(term, '!'))
+      def self.search_as_method(term)
+        where("title LIKE ?", sanitize_sql_like(term, "!"))
       end
+
+      scope :search_as_scope, -> (term) {
+        where("title LIKE ?", sanitize_sql_like(term, "!"))
+      }
+    end
+
+    assert_sql(/LIKE '20!% !_reduction!_!!'/) do
+      searchable_post.search_as_method("20% _reduction_!").to_a
     end
 
     assert_sql(/LIKE '20!% !_reduction!_!!'/) do
-      searchable_post.search("20% _reduction_!").to_a
+      searchable_post.search_as_scope("20% _reduction_!").to_a
     end
   end
 
   def test_bind_arity
-    assert_nothing_raised                                { bind '' }
-    assert_raise(ActiveRecord::PreparedStatementInvalid) { bind '', 1 }
+    assert_nothing_raised                                { bind "" }
+    assert_raise(ActiveRecord::PreparedStatementInvalid) { bind "", 1 }
 
-    assert_raise(ActiveRecord::PreparedStatementInvalid) { bind '?' }
-    assert_nothing_raised                                { bind '?', 1 }
-    assert_raise(ActiveRecord::PreparedStatementInvalid) { bind '?', 1, 1 }
+    assert_raise(ActiveRecord::PreparedStatementInvalid) { bind "?" }
+    assert_nothing_raised                                { bind "?", 1 }
+    assert_raise(ActiveRecord::PreparedStatementInvalid) { bind "?", 1, 1 }
   end
 
   def test_named_bind_variables
-    assert_equal '1', bind(':a', :a => 1) # ' ruby-mode
-    assert_equal '1 1', bind(':a :a', :a => 1)  # ' ruby-mode
+    assert_equal "1", bind(":a", a: 1) # ' ruby-mode
+    assert_equal "1 1", bind(":a :a", a: 1)  # ' ruby-mode
 
-    assert_nothing_raised { bind("'+00:00'", :foo => "bar") }
+    assert_nothing_raised { bind("'+00:00'", foo: "bar") }
   end
 
   def test_named_bind_arity
-    assert_nothing_raised                                { bind "name = :name", { name: "37signals" } }
-    assert_nothing_raised                                { bind "name = :name", { name: "37signals", id: 1 } }
-    assert_raise(ActiveRecord::PreparedStatementInvalid) { bind "name = :name", { id: 1 } }
+    assert_nothing_raised                                { bind "name = :name", name: "37signals" }
+    assert_nothing_raised                                { bind "name = :name", name: "37signals", id: 1 }
+    assert_raise(ActiveRecord::PreparedStatementInvalid) { bind "name = :name", id: 1 }
   end
 
   class SimpleEnumerable
@@ -117,50 +127,42 @@ class SanitizeTest < ActiveRecord::TestCase
   def test_bind_enumerable
     quoted_abc = %(#{ActiveRecord::Base.connection.quote('a')},#{ActiveRecord::Base.connection.quote('b')},#{ActiveRecord::Base.connection.quote('c')})
 
-    assert_equal '1,2,3', bind('?', [1, 2, 3])
-    assert_equal quoted_abc, bind('?', %w(a b c))
+    assert_equal "1,2,3", bind("?", [1, 2, 3])
+    assert_equal quoted_abc, bind("?", %w(a b c))
 
-    assert_equal '1,2,3', bind(':a', :a => [1, 2, 3])
-    assert_equal quoted_abc, bind(':a', :a => %w(a b c)) # '
+    assert_equal "1,2,3", bind(":a", a: [1, 2, 3])
+    assert_equal quoted_abc, bind(":a", a: %w(a b c)) # '
 
-    assert_equal '1,2,3', bind('?', SimpleEnumerable.new([1, 2, 3]))
-    assert_equal quoted_abc, bind('?', SimpleEnumerable.new(%w(a b c)))
+    assert_equal "1,2,3", bind("?", SimpleEnumerable.new([1, 2, 3]))
+    assert_equal quoted_abc, bind("?", SimpleEnumerable.new(%w(a b c)))
 
-    assert_equal '1,2,3', bind(':a', :a => SimpleEnumerable.new([1, 2, 3]))
-    assert_equal quoted_abc, bind(':a', :a => SimpleEnumerable.new(%w(a b c))) # '
+    assert_equal "1,2,3", bind(":a", a: SimpleEnumerable.new([1, 2, 3]))
+    assert_equal quoted_abc, bind(":a", a: SimpleEnumerable.new(%w(a b c))) # '
   end
 
   def test_bind_empty_enumerable
     quoted_nil = ActiveRecord::Base.connection.quote(nil)
-    assert_equal quoted_nil, bind('?', [])
-    assert_equal " in (#{quoted_nil})", bind(' in (?)', [])
-    assert_equal "foo in (#{quoted_nil})", bind('foo in (?)', [])
+    assert_equal quoted_nil, bind("?", [])
+    assert_equal " in (#{quoted_nil})", bind(" in (?)", [])
+    assert_equal "foo in (#{quoted_nil})", bind("foo in (?)", [])
   end
 
   def test_bind_empty_string
-    quoted_empty = ActiveRecord::Base.connection.quote('')
-    assert_equal quoted_empty, bind('?', '')
+    quoted_empty = ActiveRecord::Base.connection.quote("")
+    assert_equal quoted_empty, bind("?", "")
   end
 
   def test_bind_chars
     quoted_bambi = ActiveRecord::Base.connection.quote("Bambi")
     quoted_bambi_and_thumper = ActiveRecord::Base.connection.quote("Bambi\nand\nThumper")
-    assert_equal "name=#{quoted_bambi}", bind('name=?', "Bambi")
-    assert_equal "name=#{quoted_bambi_and_thumper}", bind('name=?', "Bambi\nand\nThumper")
-    assert_equal "name=#{quoted_bambi}", bind('name=?', "Bambi".mb_chars)
-    assert_equal "name=#{quoted_bambi_and_thumper}", bind('name=?', "Bambi\nand\nThumper".mb_chars)
-  end
-
-  def test_bind_record
-    o = Struct.new(:quoted_id).new(1)
-    assert_equal '1', bind('?', o)
-
-    os = [o] * 3
-    assert_equal '1,1,1', bind('?', os)
+    assert_equal "name=#{quoted_bambi}", bind("name=?", "Bambi")
+    assert_equal "name=#{quoted_bambi_and_thumper}", bind("name=?", "Bambi\nand\nThumper")
+    assert_equal "name=#{quoted_bambi}", bind("name=?", "Bambi".mb_chars)
+    assert_equal "name=#{quoted_bambi_and_thumper}", bind("name=?", "Bambi\nand\nThumper".mb_chars)
   end
 
   def test_named_bind_with_postgresql_type_casts
-    l = Proc.new { bind(":a::integer '2009-01-01'::date", :a => '10') }
+    l = Proc.new { bind(":a::integer '2009-01-01'::date", a: "10") }
     assert_nothing_raised(&l)
     assert_equal "#{ActiveRecord::Base.connection.quote('10')}::integer '2009-01-01'::date", l.call
   end
diff --git a/activerecord/test/cases/schema_dumper_test.rb b/activerecord/test/cases/schema_dumper_test.rb
index 12f4196724..a612ce9bb2 100644
--- a/activerecord/test/cases/schema_dumper_test.rb
+++ b/activerecord/test/cases/schema_dumper_test.rb
@@ -1,5 +1,7 @@
+# frozen_string_literal: true
+
 require "cases/helper"
-require 'support/schema_dumping_helper'
+require "support/schema_dumping_helper"
 
 class SchemaDumperTest < ActiveRecord::TestCase
   include SchemaDumpingHelper
@@ -17,10 +19,16 @@ class SchemaDumperTest < ActiveRecord::TestCase
     dump_all_table_schema []
   end
 
+  def test_dump_schema_information_with_empty_versions
+    ActiveRecord::SchemaMigration.delete_all
+    schema_info = ActiveRecord::Base.connection.dump_schema_information
+    assert_no_match(/INSERT INTO/, schema_info)
+  end
+
   def test_dump_schema_information_outputs_lexically_ordered_versions
     versions = %w{ 20100101010101 20100201010101 20100301010101 }
     versions.reverse_each do |v|
-      ActiveRecord::SchemaMigration.create!(:version => v)
+      ActiveRecord::SchemaMigration.create!(version: v)
     end
 
     schema_info = ActiveRecord::Base.connection.dump_schema_information
@@ -37,7 +45,7 @@ class SchemaDumperTest < ActiveRecord::TestCase
 
         versions = %w{ 20100101010101 20100201010101 20100301010101 }
         versions.reverse_each do |v|
-          ActiveRecord::SchemaMigration.create!(:version => v)
+          ActiveRecord::SchemaMigration.create!(version: v)
         end
 
         schema_info = ActiveRecord::Base.connection.dump_schema_information
@@ -51,13 +59,14 @@ class SchemaDumperTest < ActiveRecord::TestCase
     output = standard_dump
     assert_match %r{create_table "accounts"}, output
     assert_match %r{create_table "authors"}, output
+    assert_no_match %r{(?<=, ) do \|t\|}, output
     assert_no_match %r{create_table "schema_migrations"}, output
     assert_no_match %r{create_table "ar_internal_metadata"}, output
   end
 
   def test_schema_dump_uses_force_cascade_on_create_table
     output = dump_table_schema "authors"
-    assert_match %r{create_table "authors", force: :cascade}, output
+    assert_match %r{create_table "authors",.* force: :cascade}, output
   end
 
   def test_schema_dump_excludes_sqlite_sequence
@@ -70,38 +79,35 @@ class SchemaDumperTest < ActiveRecord::TestCase
     assert_match %r{create_table "CamelCase"}, output
   end
 
-  def assert_line_up(lines, pattern, required = false)
+  def assert_no_line_up(lines, pattern)
     return assert(true) if lines.empty?
     matches = lines.map { |line| line.match(pattern) }
-    assert matches.all? if required
     matches.compact!
     return assert(true) if matches.empty?
-    assert_equal 1, matches.map{ |match| match.offset(0).first }.uniq.length
+    line_matches = lines.map { |line| [line, line.match(pattern)] }.select { |line, match| match }
+    assert line_matches.all? { |line, match|
+      start = match.offset(0).first
+      line[start - 2..start - 1] == ", "
+    }
   end
 
   def column_definition_lines(output = standard_dump)
-    output.scan(/^( *)create_table.*?\n(.*?)^\1end/m).map{ |m| m.last.split(/\n/) }
+    output.scan(/^( *)create_table.*?\n(.*?)^\1end/m).map { |m| m.last.split(/\n/) }
   end
 
-  def test_types_line_up
+  def test_types_no_line_up
     column_definition_lines.each do |column_set|
       next if column_set.empty?
 
-      lengths = column_set.map do |column|
-        if match = column.match(/\bt\.\w+\s+(?="\w+?")/)
-          match[0].length
-        end
-      end.compact
-
-      assert_equal 1, lengths.uniq.length
+      assert column_set.all? { |column| !column.match(/\bt\.\w+\s{2,}/) }
     end
   end
 
-  def test_arguments_line_up
+  def test_arguments_no_line_up
     column_definition_lines.each do |column_set|
-      assert_line_up(column_set, /default: /)
-      assert_line_up(column_set, /limit: /)
-      assert_line_up(column_set, /null: /)
+      assert_no_line_up(column_set, /default: /)
+      assert_no_line_up(column_set, /limit: /)
+      assert_no_line_up(column_set, /null: /)
     end
   end
 
@@ -118,44 +124,29 @@ class SchemaDumperTest < ActiveRecord::TestCase
   def test_schema_dump_includes_limit_constraint_for_integer_columns
     output = dump_all_table_schema([/^(?!integer_limits)/])
 
-    assert_match %r{c_int_without_limit}, output
+    assert_match %r{"c_int_without_limit"(?!.*limit)}, output
 
     if current_adapter?(:PostgreSQLAdapter)
-      assert_no_match %r{c_int_without_limit.*limit:}, output
-
       assert_match %r{c_int_1.*limit: 2}, output
       assert_match %r{c_int_2.*limit: 2}, output
 
       # int 3 is 4 bytes in postgresql
-      assert_match %r{c_int_3.*}, output
-      assert_no_match %r{c_int_3.*limit:}, output
-
-      assert_match %r{c_int_4.*}, output
-      assert_no_match %r{c_int_4.*limit:}, output
+      assert_match %r{"c_int_3"(?!.*limit)}, output
+      assert_match %r{"c_int_4"(?!.*limit)}, output
     elsif current_adapter?(:Mysql2Adapter)
-      assert_match %r{c_int_without_limit"$}, output
-
       assert_match %r{c_int_1.*limit: 1}, output
       assert_match %r{c_int_2.*limit: 2}, output
       assert_match %r{c_int_3.*limit: 3}, output
 
-      assert_match %r{c_int_4.*}, output
-      assert_no_match %r{c_int_4.*:limit}, output
+      assert_match %r{"c_int_4"(?!.*limit)}, output
     elsif current_adapter?(:SQLite3Adapter)
-      assert_no_match %r{c_int_without_limit.*limit:}, output
-
       assert_match %r{c_int_1.*limit: 1}, output
       assert_match %r{c_int_2.*limit: 2}, output
       assert_match %r{c_int_3.*limit: 3}, output
       assert_match %r{c_int_4.*limit: 4}, output
     end
 
-    if current_adapter?(:SQLite3Adapter)
-      assert_match %r{c_int_5.*limit: 5}, output
-      assert_match %r{c_int_6.*limit: 6}, output
-      assert_match %r{c_int_7.*limit: 7}, output
-      assert_match %r{c_int_8.*limit: 8}, output
-    elsif current_adapter?(:OracleAdapter)
+    if current_adapter?(:SQLite3Adapter, :OracleAdapter)
       assert_match %r{c_int_5.*limit: 5}, output
       assert_match %r{c_int_6.*limit: 6}, output
       assert_match %r{c_int_7.*limit: 7}, output
@@ -169,7 +160,7 @@ class SchemaDumperTest < ActiveRecord::TestCase
   end
 
   def test_schema_dump_with_string_ignored_table
-    output = dump_all_table_schema(['accounts'])
+    output = dump_all_table_schema(["accounts"])
     assert_no_match %r{create_table "accounts"}, output
     assert_match %r{create_table "authors"}, output
     assert_no_match %r{create_table "schema_migrations"}, output
@@ -185,27 +176,47 @@ class SchemaDumperTest < ActiveRecord::TestCase
   end
 
   def test_schema_dumps_index_columns_in_right_order
-    index_definition = standard_dump.split(/\n/).grep(/t\.index.*company_index/).first.strip
-    if current_adapter?(:Mysql2Adapter, :PostgreSQLAdapter)
-      assert_equal 't.index ["firm_id", "type", "rating"], name: "company_index", using: :btree', index_definition
+    index_definition = dump_table_schema("companies").split(/\n/).grep(/t\.index.*company_index/).first.strip
+    if current_adapter?(:Mysql2Adapter)
+      if ActiveRecord::Base.connection.supports_index_sort_order?
+        assert_equal 't.index ["firm_id", "type", "rating"], name: "company_index", length: { type: 10 }, order: { rating: :desc }', index_definition
+      else
+        assert_equal 't.index ["firm_id", "type", "rating"], name: "company_index", length: { type: 10 }', index_definition
+      end
+    elsif ActiveRecord::Base.connection.supports_index_sort_order?
+      assert_equal 't.index ["firm_id", "type", "rating"], name: "company_index", order: { rating: :desc }', index_definition
     else
       assert_equal 't.index ["firm_id", "type", "rating"], name: "company_index"', index_definition
     end
   end
 
   def test_schema_dumps_partial_indices
-    index_definition = standard_dump.split(/\n/).grep(/t\.index.*company_partial_index/).first.strip
-    if current_adapter?(:PostgreSQLAdapter)
-      assert_equal 't.index ["firm_id", "type"], name: "company_partial_index", where: "(rating > 10)", using: :btree', index_definition
-    elsif current_adapter?(:Mysql2Adapter)
-      assert_equal 't.index ["firm_id", "type"], name: "company_partial_index", using: :btree', index_definition
-    elsif current_adapter?(:SQLite3Adapter) && ActiveRecord::Base.connection.supports_partial_index?
-      assert_equal 't.index ["firm_id", "type"], name: "company_partial_index", where: "rating > 10"', index_definition
+    index_definition = dump_table_schema("companies").split(/\n/).grep(/t\.index.*company_partial_index/).first.strip
+    if current_adapter?(:PostgreSQLAdapter, :SQLite3Adapter) && ActiveRecord::Base.connection.supports_partial_index?
+      assert_equal 't.index ["firm_id", "type"], name: "company_partial_index", where: "(rating > 10)"', index_definition
     else
       assert_equal 't.index ["firm_id", "type"], name: "company_partial_index"', index_definition
     end
   end
 
+  def test_schema_dumps_index_sort_order
+    index_definition = dump_table_schema("companies").split(/\n/).grep(/t\.index.*_name_and_rating/).first.strip
+    if ActiveRecord::Base.connection.supports_index_sort_order?
+      assert_equal 't.index ["name", "rating"], name: "index_companies_on_name_and_rating", order: :desc', index_definition
+    else
+      assert_equal 't.index ["name", "rating"], name: "index_companies_on_name_and_rating"', index_definition
+    end
+  end
+
+  def test_schema_dumps_index_length
+    index_definition = dump_table_schema("companies").split(/\n/).grep(/t\.index.*_name_and_description/).first.strip
+    if current_adapter?(:Mysql2Adapter)
+      assert_equal 't.index ["name", "description"], name: "index_companies_on_name_and_description", length: 10', index_definition
+    else
+      assert_equal 't.index ["name", "description"], name: "index_companies_on_name_and_description"', index_definition
+    end
+  end
+
   def test_schema_dump_should_honor_nonstandard_primary_keys
     output = standard_dump
     match = output.match(%r{create_table "movies"(.*)do})
@@ -214,20 +225,25 @@ class SchemaDumperTest < ActiveRecord::TestCase
   end
 
   def test_schema_dump_should_use_false_as_default
-    output = standard_dump
+    output = dump_table_schema "booleans"
     assert_match %r{t\.boolean\s+"has_fun",.+default: false}, output
   end
 
   def test_schema_dump_does_not_include_limit_for_text_field
-    output = standard_dump
+    output = dump_table_schema "admin_users"
     assert_match %r{t\.text\s+"params"$}, output
   end
 
   def test_schema_dump_does_not_include_limit_for_binary_field
-    output = standard_dump
+    output = dump_table_schema "binaries"
     assert_match %r{t\.binary\s+"data"$}, output
   end
 
+  def test_schema_dump_does_not_include_limit_for_float_field
+    output = dump_table_schema "numeric_data"
+    assert_match %r{t\.float\s+"temperature"$}, output
+  end
+
   if current_adapter?(:Mysql2Adapter)
     def test_schema_dump_includes_length_for_mysql_binary_fields
       output = standard_dump
@@ -253,9 +269,9 @@ class SchemaDumperTest < ActiveRecord::TestCase
     end
 
     def test_schema_dumps_index_type
-      output = standard_dump
-      assert_match %r{t\.index \["awesome"\], name: "index_key_tests_on_awesome", type: :fulltext}, output
-      assert_match %r{t\.index \["pizza"\], name: "index_key_tests_on_pizza", using: :btree}, output
+      output = dump_table_schema "key_tests"
+      assert_match %r{t\.index \["awesome"\], name: "index_key_tests_on_awesome", type: :fulltext$}, output
+      assert_match %r{t\.index \["pizza"\], name: "index_key_tests_on_pizza"$}, output
     end
   end
 
@@ -266,39 +282,62 @@ class SchemaDumperTest < ActiveRecord::TestCase
 
   if current_adapter?(:PostgreSQLAdapter)
     def test_schema_dump_includes_bigint_default
-      output = standard_dump
+      output = dump_table_schema "defaults"
       assert_match %r{t\.bigint\s+"bigint_default",\s+default: 0}, output
     end
 
     def test_schema_dump_includes_limit_on_array_type
-      output = standard_dump
+      output = dump_table_schema "bigint_array"
       assert_match %r{t\.bigint\s+"big_int_data_points\",\s+array: true}, output
     end
 
     def test_schema_dump_allows_array_of_decimal_defaults
-      output = standard_dump
+      output = dump_table_schema "bigint_array"
       assert_match %r{t\.decimal\s+"decimal_array_default",\s+default: \["1.23", "3.45"\],\s+array: true}, output
     end
 
     def test_schema_dump_expression_indices
-      index_definition = standard_dump.split(/\n/).grep(/t\.index.*company_expression_index/).first.strip
-      assert_equal 't.index "lower((name)::text)", name: "company_expression_index", using: :btree', index_definition
+      index_definition = dump_table_schema("companies").split(/\n/).grep(/t\.index.*company_expression_index/).first.strip
+      assert_equal 't.index "lower((name)::text)", name: "company_expression_index"', index_definition
     end
 
-    if ActiveRecord::Base.connection.supports_extensions?
-      def test_schema_dump_includes_extensions
-        connection = ActiveRecord::Base.connection
+    def test_schema_dump_interval_type
+      output = dump_table_schema "postgresql_times"
+      assert_match %r{t\.interval\s+"time_interval"$}, output
+      assert_match %r{t\.interval\s+"scaled_time_interval",\s+precision: 6$}, output
+    end
 
-        connection.stubs(:extensions).returns(['hstore'])
-        output = perform_schema_dump
-        assert_match "# These are extensions that must be enabled", output
-        assert_match %r{enable_extension "hstore"}, output
+    def test_schema_dump_oid_type
+      output = dump_table_schema "postgresql_oids"
+      assert_match %r{t\.oid\s+"obj_id"$}, output
+    end
 
-        connection.stubs(:extensions).returns([])
-        output = perform_schema_dump
-        assert_no_match "# These are extensions that must be enabled", output
-        assert_no_match %r{enable_extension}, output
-      end
+    def test_schema_dump_includes_extensions
+      connection = ActiveRecord::Base.connection
+
+      connection.stubs(:extensions).returns(["hstore"])
+      output = perform_schema_dump
+      assert_match "# These are extensions that must be enabled", output
+      assert_match %r{enable_extension "hstore"}, output
+
+      connection.stubs(:extensions).returns([])
+      output = perform_schema_dump
+      assert_no_match "# These are extensions that must be enabled", output
+      assert_no_match %r{enable_extension}, output
+    end
+
+    def test_schema_dump_includes_extensions_in_alphabetic_order
+      connection = ActiveRecord::Base.connection
+
+      connection.stubs(:extensions).returns(["hstore", "uuid-ossp", "xml2"])
+      output = perform_schema_dump
+      enabled_extensions = output.scan(%r{enable_extension "(.+)"}).flatten
+      assert_equal ["hstore", "uuid-ossp", "xml2"], enabled_extensions
+
+      connection.stubs(:extensions).returns(["uuid-ossp", "xml2", "hstore"])
+      output = perform_schema_dump
+      enabled_extensions = output.scan(%r{enable_extension "(.+)"}).flatten
+      assert_equal ["hstore", "uuid-ossp", "xml2"], enabled_extensions
     end
   end
 
@@ -324,7 +363,7 @@ class SchemaDumperTest < ActiveRecord::TestCase
 
   def test_schema_dump_keeps_id_false_when_id_is_false_and_unique_not_null_column_added
     output = standard_dump
-    assert_match %r{create_table "subscribers", id: false}, output
+    assert_match %r{create_table "string_key_objects", id: false}, output
   end
 
   if ActiveRecord::Base.connection.supports_foreign_keys?
@@ -346,9 +385,9 @@ class SchemaDumperTest < ActiveRecord::TestCase
 
       create_table("dogs") do |t|
         t.column :name, :string
-        t.column :owner_id, :integer
+        t.references :owner
         t.index [:name]
-        t.foreign_key :dog_owners, column: "owner_id" if supports_foreign_keys?
+        t.foreign_key :dog_owners, column: "owner_id"
       end
     end
     def down
@@ -359,8 +398,8 @@ class SchemaDumperTest < ActiveRecord::TestCase
 
   def test_schema_dump_with_table_name_prefix_and_suffix
     original, $stdout = $stdout, StringIO.new
-    ActiveRecord::Base.table_name_prefix = 'foo_'
-    ActiveRecord::Base.table_name_suffix = '_bar'
+    ActiveRecord::Base.table_name_prefix = "foo_"
+    ActiveRecord::Base.table_name_suffix = "_bar"
 
     migration = CreateDogMigration.new
     migration.migrate(:up)
@@ -378,7 +417,32 @@ class SchemaDumperTest < ActiveRecord::TestCase
   ensure
     migration.migrate(:down)
 
-    ActiveRecord::Base.table_name_suffix = ActiveRecord::Base.table_name_prefix = ''
+    ActiveRecord::Base.table_name_suffix = ActiveRecord::Base.table_name_prefix = ""
+    $stdout = original
+  end
+
+  def test_schema_dump_with_table_name_prefix_and_suffix_regexp_escape
+    original, $stdout = $stdout, StringIO.new
+    ActiveRecord::Base.table_name_prefix = "foo$"
+    ActiveRecord::Base.table_name_suffix = "$bar"
+
+    migration = CreateDogMigration.new
+    migration.migrate(:up)
+
+    output = perform_schema_dump
+    assert_no_match %r{create_table "foo\$.+\$bar"}, output
+    assert_no_match %r{add_index "foo\$.+\$bar"}, output
+    assert_no_match %r{create_table "schema_migrations"}, output
+    assert_no_match %r{create_table "ar_internal_metadata"}, output
+
+    if ActiveRecord::Base.connection.supports_foreign_keys?
+      assert_no_match %r{add_foreign_key "foo\$.+\$bar"}, output
+      assert_no_match %r{add_foreign_key "[^"]+", "foo\$.+\$bar"}, output
+    end
+  ensure
+    migration.migrate(:down)
+
+    ActiveRecord::Base.table_name_suffix = ActiveRecord::Base.table_name_prefix = ""
     $stdout = original
   end
 
@@ -396,7 +460,7 @@ class SchemaDumperTest < ActiveRecord::TestCase
 
     original_table_name_prefix = ActiveRecord::Base.table_name_prefix
     original_schema_dumper_ignore_tables = ActiveRecord::SchemaDumper.ignore_tables
-    ActiveRecord::Base.table_name_prefix = 'omg_'
+    ActiveRecord::Base.table_name_prefix = "omg_"
     ActiveRecord::SchemaDumper.ignore_tables = ["cats"]
     migration = create_cat_migration.new
     migration.migrate(:up)
@@ -420,25 +484,40 @@ class SchemaDumperDefaultsTest < ActiveRecord::TestCase
 
   setup do
     @connection = ActiveRecord::Base.connection
-    @connection.create_table :defaults, force: true do |t|
+    @connection.create_table :dump_defaults, force: true do |t|
       t.string   :string_with_default,   default: "Hello!"
-      t.date     :date_with_default,     default: '2014-06-05'
+      t.date     :date_with_default,     default: "2014-06-05"
       t.datetime :datetime_with_default, default: "2014-06-05 07:17:04"
       t.time     :time_with_default,     default: "07:17:04"
+      t.decimal  :decimal_with_default,  default: "1234567890.0123456789", precision: 20, scale: 10
+    end
+
+    if current_adapter?(:PostgreSQLAdapter)
+      @connection.create_table :infinity_defaults, force: true do |t|
+        t.float    :float_with_inf_default,    default: Float::INFINITY
+        t.float    :float_with_nan_default,    default: Float::NAN
+      end
     end
   end
 
   teardown do
-    return unless @connection
-    @connection.drop_table 'defaults', if_exists: true
+    @connection.drop_table "dump_defaults", if_exists: true
   end
 
   def test_schema_dump_defaults_with_universally_supported_types
-    output = dump_table_schema('defaults')
+    output = dump_table_schema("dump_defaults")
 
     assert_match %r{t\.string\s+"string_with_default",.*?default: "Hello!"}, output
-    assert_match %r{t\.date\s+"date_with_default",\s+default: '2014-06-05'}, output
-    assert_match %r{t\.datetime\s+"datetime_with_default",\s+default: '2014-06-05 07:17:04'}, output
-    assert_match %r{t\.time\s+"time_with_default",\s+default: '2000-01-01 07:17:04'}, output
+    assert_match %r{t\.date\s+"date_with_default",\s+default: "2014-06-05"}, output
+    assert_match %r{t\.datetime\s+"datetime_with_default",\s+default: "2014-06-05 07:17:04"}, output
+    assert_match %r{t\.time\s+"time_with_default",\s+default: "2000-01-01 07:17:04"}, output
+    assert_match %r{t\.decimal\s+"decimal_with_default",\s+precision: 20,\s+scale: 10,\s+default: "1234567890.0123456789"}, output
+  end
+
+  def test_schema_dump_with_float_column_infinity_default
+    skip unless current_adapter?(:PostgreSQLAdapter)
+    output = dump_table_schema("infinity_defaults")
+    assert_match %r{t\.float\s+"float_with_inf_default",\s+default: ::Float::INFINITY}, output
+    assert_match %r{t\.float\s+"float_with_nan_default",\s+default: ::Float::NAN}, output
   end
 end
diff --git a/activerecord/test/cases/schema_loading_test.rb b/activerecord/test/cases/schema_loading_test.rb
index 3d92a5e104..f539156466 100644
--- a/activerecord/test/cases/schema_loading_test.rb
+++ b/activerecord/test/cases/schema_loading_test.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require "cases/helper"
 
 module SchemaLoadCounter
@@ -8,7 +10,7 @@ module SchemaLoadCounter
 
     def load_schema!
       self.load_schema_calls ||= 0
-      self.load_schema_calls +=1
+      self.load_schema_calls += 1
       super
     end
   end
diff --git a/activerecord/test/cases/scoping/default_scoping_test.rb b/activerecord/test/cases/scoping/default_scoping_test.rb
index dcd09b6973..fdfeabaa3b 100644
--- a/activerecord/test/cases/scoping/default_scoping_test.rb
+++ b/activerecord/test/cases/scoping/default_scoping_test.rb
@@ -1,16 +1,19 @@
-require 'cases/helper'
-require 'models/post'
-require 'models/comment'
-require 'models/developer'
-require 'models/computer'
-require 'models/vehicle'
-require 'models/cat'
+# frozen_string_literal: true
+
+require "cases/helper"
+require "models/post"
+require "models/comment"
+require "models/developer"
+require "models/computer"
+require "models/vehicle"
+require "models/cat"
+require "concurrent/atomic/cyclic_barrier"
 
 class DefaultScopingTest < ActiveRecord::TestCase
   fixtures :developers, :posts, :comments
 
   def test_default_scope
-    expected = Developer.all.merge!(:order => 'salary DESC').to_a.collect(&:salary)
+    expected = Developer.all.merge!(order: "salary DESC").to_a.collect(&:salary)
     received = DeveloperOrderedBySalary.all.collect(&:salary)
     assert_equal expected, received
   end
@@ -49,59 +52,48 @@ class DefaultScopingTest < ActiveRecord::TestCase
   end
 
   def test_default_scope_with_conditions_string
-    assert_equal Developer.where(name: 'David').map(&:id).sort, DeveloperCalledDavid.all.map(&:id).sort
-    assert_equal nil, DeveloperCalledDavid.create!.name
+    assert_equal Developer.where(name: "David").map(&:id).sort, DeveloperCalledDavid.all.map(&:id).sort
+    assert_nil DeveloperCalledDavid.create!.name
   end
 
   def test_default_scope_with_conditions_hash
-    assert_equal Developer.where(name: 'Jamis').map(&:id).sort, DeveloperCalledJamis.all.map(&:id).sort
-    assert_equal 'Jamis', DeveloperCalledJamis.create!.name
-  end
-
-  unless in_memory_db?
-    def test_default_scoping_with_threads
-      2.times do
-        Thread.new {
-          assert DeveloperOrderedBySalary.all.to_sql.include?('salary DESC')
-          DeveloperOrderedBySalary.connection.close
-        }.join
-      end
-    end
+    assert_equal Developer.where(name: "Jamis").map(&:id).sort, DeveloperCalledJamis.all.map(&:id).sort
+    assert_equal "Jamis", DeveloperCalledJamis.create!.name
   end
 
   def test_default_scope_with_inheritance
     wheres = InheritedPoorDeveloperCalledJamis.all.where_values_hash
-    assert_equal "Jamis", wheres['name']
-    assert_equal 50000,   wheres['salary']
+    assert_equal "Jamis", wheres["name"]
+    assert_equal 50000,   wheres["salary"]
   end
 
   def test_default_scope_with_module_includes
     wheres = ModuleIncludedPoorDeveloperCalledJamis.all.where_values_hash
-    assert_equal "Jamis", wheres['name']
-    assert_equal 50000,   wheres['salary']
+    assert_equal "Jamis", wheres["name"]
+    assert_equal 50000,   wheres["salary"]
   end
 
   def test_default_scope_with_multiple_calls
     wheres = MultiplePoorDeveloperCalledJamis.all.where_values_hash
-    assert_equal "Jamis", wheres['name']
-    assert_equal 50000,   wheres['salary']
+    assert_equal "Jamis", wheres["name"]
+    assert_equal 50000,   wheres["salary"]
   end
 
   def test_scope_overwrites_default
-    expected = Developer.all.merge!(order: 'salary DESC, name DESC').to_a.collect(&:name)
+    expected = Developer.all.merge!(order: "salary DESC, name DESC").to_a.collect(&:name)
     received = DeveloperOrderedBySalary.by_name.to_a.collect(&:name)
     assert_equal expected, received
   end
 
   def test_reorder_overrides_default_scope_order
-    expected = Developer.order('name DESC').collect(&:name)
-    received = DeveloperOrderedBySalary.reorder('name DESC').collect(&:name)
+    expected = Developer.order("name DESC").collect(&:name)
+    received = DeveloperOrderedBySalary.reorder("name DESC").collect(&:name)
     assert_equal expected, received
   end
 
   def test_order_after_reorder_combines_orders
-    expected = Developer.order('name DESC, id DESC').collect { |dev| [dev.name, dev.id] }
-    received = Developer.order('name ASC').reorder('name DESC').order('id DESC').collect { |dev| [dev.name, dev.id] }
+    expected = Developer.order("name DESC, id DESC").collect { |dev| [dev.name, dev.id] }
+    received = Developer.order("name ASC").reorder("name DESC").order("id DESC").collect { |dev| [dev.name, dev.id] }
     assert_equal expected, received
   end
 
@@ -112,107 +104,107 @@ class DefaultScopingTest < ActiveRecord::TestCase
   end
 
   def test_unscope_after_reordering_and_combining
-    expected = Developer.order('id DESC, name DESC').collect { |dev| [dev.name, dev.id] }
-    received = DeveloperOrderedBySalary.reorder('name DESC').unscope(:order).order('id DESC, name DESC').collect { |dev| [dev.name, dev.id] }
+    expected = Developer.order("id DESC, name DESC").collect { |dev| [dev.name, dev.id] }
+    received = DeveloperOrderedBySalary.reorder("name DESC").unscope(:order).order("id DESC, name DESC").collect { |dev| [dev.name, dev.id] }
     assert_equal expected, received
 
     expected_2 = Developer.all.collect { |dev| [dev.name, dev.id] }
-    received_2 = Developer.order('id DESC, name DESC').unscope(:order).collect { |dev| [dev.name, dev.id] }
+    received_2 = Developer.order("id DESC, name DESC").unscope(:order).collect { |dev| [dev.name, dev.id] }
     assert_equal expected_2, received_2
 
     expected_3 = Developer.all.collect { |dev| [dev.name, dev.id] }
-    received_3 = Developer.reorder('name DESC').unscope(:order).collect { |dev| [dev.name, dev.id] }
+    received_3 = Developer.reorder("name DESC").unscope(:order).collect { |dev| [dev.name, dev.id] }
     assert_equal expected_3, received_3
   end
 
   def test_unscope_with_where_attributes
-    expected = Developer.order('salary DESC').collect(&:name)
-    received = DeveloperOrderedBySalary.where(name: 'David').unscope(where: :name).collect(&:name)
-    assert_equal expected, received
+    expected = Developer.order("salary DESC").collect(&:name)
+    received = DeveloperOrderedBySalary.where(name: "David").unscope(where: :name).collect(&:name)
+    assert_equal expected.sort, received.sort
 
-    expected_2 = Developer.order('salary DESC').collect(&:name)
-    received_2 = DeveloperOrderedBySalary.select("id").where("name" => "Jamis").unscope({:where => :name}, :select).collect(&:name)
-    assert_equal expected_2, received_2
+    expected_2 = Developer.order("salary DESC").collect(&:name)
+    received_2 = DeveloperOrderedBySalary.select("id").where("name" => "Jamis").unscope({ where: :name }, :select).collect(&:name)
+    assert_equal expected_2.sort, received_2.sort
 
-    expected_3 = Developer.order('salary DESC').collect(&:name)
+    expected_3 = Developer.order("salary DESC").collect(&:name)
     received_3 = DeveloperOrderedBySalary.select("id").where("name" => "Jamis").unscope(:select, :where).collect(&:name)
-    assert_equal expected_3, received_3
+    assert_equal expected_3.sort, received_3.sort
 
-    expected_4 = Developer.order('salary DESC').collect(&:name)
+    expected_4 = Developer.order("salary DESC").collect(&:name)
     received_4 = DeveloperOrderedBySalary.where.not("name" => "Jamis").unscope(where: :name).collect(&:name)
-    assert_equal expected_4, received_4
+    assert_equal expected_4.sort, received_4.sort
 
-    expected_5 = Developer.order('salary DESC').collect(&:name)
+    expected_5 = Developer.order("salary DESC").collect(&:name)
     received_5 = DeveloperOrderedBySalary.where.not("name" => ["Jamis", "David"]).unscope(where: :name).collect(&:name)
-    assert_equal expected_5, received_5
+    assert_equal expected_5.sort, received_5.sort
 
-    expected_6 = Developer.order('salary DESC').collect(&:name)
-    received_6 = DeveloperOrderedBySalary.where(Developer.arel_table['name'].eq('David')).unscope(where: :name).collect(&:name)
-    assert_equal expected_6, received_6
+    expected_6 = Developer.order("salary DESC").collect(&:name)
+    received_6 = DeveloperOrderedBySalary.where(Developer.arel_table["name"].eq("David")).unscope(where: :name).collect(&:name)
+    assert_equal expected_6.sort, received_6.sort
 
-    expected_7 = Developer.order('salary DESC').collect(&:name)
-    received_7 = DeveloperOrderedBySalary.where(Developer.arel_table[:name].eq('David')).unscope(where: :name).collect(&:name)
-    assert_equal expected_7, received_7
+    expected_7 = Developer.order("salary DESC").collect(&:name)
+    received_7 = DeveloperOrderedBySalary.where(Developer.arel_table[:name].eq("David")).unscope(where: :name).collect(&:name)
+    assert_equal expected_7.sort, received_7.sort
   end
 
   def test_unscope_comparison_where_clauses
     # unscoped for WHERE (`developers`.`id` <= 2)
-    expected = Developer.order('salary DESC').collect(&:name)
+    expected = Developer.order("salary DESC").collect(&:name)
     received = DeveloperOrderedBySalary.where(id: -Float::INFINITY..2).unscope(where: :id).collect { |dev| dev.name }
-    assert_equal expected, received
+    assert_equal expected.sort, received.sort
 
     # unscoped for WHERE (`developers`.`id` < 2)
-    expected = Developer.order('salary DESC').collect(&:name)
+    expected = Developer.order("salary DESC").collect(&:name)
     received = DeveloperOrderedBySalary.where(id: -Float::INFINITY...2).unscope(where: :id).collect { |dev| dev.name }
-    assert_equal expected, received
+    assert_equal expected.sort, received.sort
   end
 
   def test_unscope_multiple_where_clauses
-    expected = Developer.order('salary DESC').collect(&:name)
-    received = DeveloperOrderedBySalary.where(name: 'Jamis').where(id: 1).unscope(where: [:name, :id]).collect(&:name)
-    assert_equal expected, received
+    expected = Developer.order("salary DESC").collect(&:name)
+    received = DeveloperOrderedBySalary.where(name: "Jamis").where(id: 1).unscope(where: [:name, :id]).collect(&:name)
+    assert_equal expected.sort, received.sort
   end
 
   def test_unscope_string_where_clauses_involved
-    dev_relation = Developer.order('salary DESC').where("created_at > ?", 1.year.ago)
+    dev_relation = Developer.order("salary DESC").where("created_at > ?", 1.year.ago)
     expected = dev_relation.collect(&:name)
 
-    dev_ordered_relation = DeveloperOrderedBySalary.where(name: 'Jamis').where("created_at > ?", 1.year.ago)
+    dev_ordered_relation = DeveloperOrderedBySalary.where(name: "Jamis").where("created_at > ?", 1.year.ago)
     received = dev_ordered_relation.unscope(where: [:name]).collect(&:name)
 
-    assert_equal expected, received
+    assert_equal expected.sort, received.sort
   end
 
   def test_unscope_with_grouping_attributes
-    expected = Developer.order('salary DESC').collect(&:name)
+    expected = Developer.order("salary DESC").collect(&:name)
     received = DeveloperOrderedBySalary.group(:name).unscope(:group).collect(&:name)
-    assert_equal expected, received
+    assert_equal expected.sort, received.sort
 
-    expected_2 = Developer.order('salary DESC').collect(&:name)
+    expected_2 = Developer.order("salary DESC").collect(&:name)
     received_2 = DeveloperOrderedBySalary.group("name").unscope(:group).collect(&:name)
-    assert_equal expected_2, received_2
+    assert_equal expected_2.sort, received_2.sort
   end
 
   def test_unscope_with_limit_in_query
-    expected = Developer.order('salary DESC').collect(&:name)
+    expected = Developer.order("salary DESC").collect(&:name)
     received = DeveloperOrderedBySalary.limit(1).unscope(:limit).collect(&:name)
-    assert_equal expected, received
+    assert_equal expected.sort, received.sort
   end
 
   def test_order_to_unscope_reordering
-    scope = DeveloperOrderedBySalary.order('salary DESC, name ASC').reverse_order.unscope(:order)
-    assert !(scope.to_sql =~ /order/i)
+    scope = DeveloperOrderedBySalary.order("salary DESC, name ASC").reverse_order.unscope(:order)
+    assert !/order/i.match?(scope.to_sql)
   end
 
   def test_unscope_reverse_order
     expected = Developer.all.collect(&:name)
-    received = Developer.order('salary DESC').reverse_order.unscope(:order).collect(&:name)
+    received = Developer.order("salary DESC").reverse_order.unscope(:order).collect(&:name)
     assert_equal expected, received
   end
 
   def test_unscope_select
-    expected = Developer.order('salary ASC').collect(&:name)
-    received = Developer.order('salary DESC').reverse_order.select(:name).unscope(:select).collect(&:name)
+    expected = Developer.order("salary ASC").collect(&:name)
+    received = Developer.order("salary DESC").reverse_order.select(:name).unscope(:select).collect(&:name)
     assert_equal expected, received
 
     expected_2 = Developer.all.collect(&:id)
@@ -228,7 +220,7 @@ class DefaultScopingTest < ActiveRecord::TestCase
 
   def test_unscope_joins_and_select_on_developers_projects
     expected = Developer.all.collect(&:name)
-    received = Developer.joins('JOIN developers_projects ON id = developer_id').select(:id).unscope(:joins, :select).collect(&:name)
+    received = Developer.joins("JOIN developers_projects ON id = developer_id").select(:id).unscope(:joins, :select).collect(&:name)
     assert_equal expected, received
   end
 
@@ -249,8 +241,8 @@ class DefaultScopingTest < ActiveRecord::TestCase
       scope :by_name, -> name { unscope(where: :name).where(name: name) }
     end
 
-    expected = developer_klass.where(name: 'Jamis').collect { |dev| [dev.name, dev.id] }
-    received = developer_klass.where(name: 'David').by_name('Jamis').collect { |dev| [dev.name, dev.id] }
+    expected = developer_klass.where(name: "Jamis").collect { |dev| [dev.name, dev.id] }
+    received = developer_klass.where(name: "David").by_name("Jamis").collect { |dev| [dev.name, dev.id] }
     assert_equal expected, received
   end
 
@@ -264,11 +256,11 @@ class DefaultScopingTest < ActiveRecord::TestCase
     end
 
     assert_raises(ArgumentError) do
-      Developer.order('name DESC').reverse_order.unscope(:reverse_order)
+      Developer.order("name DESC").reverse_order.unscope(:reverse_order)
     end
 
     assert_raises(ArgumentError) do
-      Developer.order('name DESC').where(name: "Jamis").unscope()
+      Developer.order("name DESC").where(name: "Jamis").unscope()
     end
   end
 
@@ -303,35 +295,35 @@ class DefaultScopingTest < ActiveRecord::TestCase
   end
 
   def test_order_in_default_scope_should_not_prevail
-    expected = Developer.all.merge!(order: 'salary desc').to_a.collect(&:salary)
-    received = DeveloperOrderedBySalary.all.merge!(order: 'salary').to_a.collect(&:salary)
+    expected = Developer.all.merge!(order: "salary desc").to_a.collect(&:salary)
+    received = DeveloperOrderedBySalary.all.merge!(order: "salary").to_a.collect(&:salary)
     assert_equal expected, received
   end
 
   def test_create_attribute_overwrites_default_scoping
-    assert_equal 'David', PoorDeveloperCalledJamis.create!(:name => 'David').name
-    assert_equal 200000, PoorDeveloperCalledJamis.create!(:name => 'David', :salary => 200000).salary
+    assert_equal "David", PoorDeveloperCalledJamis.create!(name: "David").name
+    assert_equal 200000, PoorDeveloperCalledJamis.create!(name: "David", salary: 200000).salary
   end
 
   def test_create_attribute_overwrites_default_values
-    assert_equal nil, PoorDeveloperCalledJamis.create!(:salary => nil).salary
-    assert_equal 50000, PoorDeveloperCalledJamis.create!(:name => 'David').salary
+    assert_nil PoorDeveloperCalledJamis.create!(salary: nil).salary
+    assert_equal 50000, PoorDeveloperCalledJamis.create!(name: "David").salary
   end
 
   def test_default_scope_attribute
-    jamis = PoorDeveloperCalledJamis.new(:name => 'David')
+    jamis = PoorDeveloperCalledJamis.new(name: "David")
     assert_equal 50000, jamis.salary
   end
 
   def test_where_attribute
-    aaron = PoorDeveloperCalledJamis.where(:salary => 20).new(:name => 'Aaron')
+    aaron = PoorDeveloperCalledJamis.where(salary: 20).new(name: "Aaron")
     assert_equal 20, aaron.salary
-    assert_equal 'Aaron', aaron.name
+    assert_equal "Aaron", aaron.name
   end
 
   def test_where_attribute_merge
-    aaron = PoorDeveloperCalledJamis.where(:name => 'foo').new(:name => 'Aaron')
-    assert_equal 'Aaron', aaron.name
+    aaron = PoorDeveloperCalledJamis.where(name: "foo").new(name: "Aaron")
+    assert_equal "Aaron", aaron.name
   end
 
   def test_scope_composed_by_limit_and_then_offset_is_equal_to_scope_composed_by_offset_and_then_limit
@@ -341,33 +333,38 @@ class DefaultScopingTest < ActiveRecord::TestCase
   end
 
   def test_create_with_merge
-    aaron = PoorDeveloperCalledJamis.create_with(:name => 'foo', :salary => 20).merge(
-              PoorDeveloperCalledJamis.create_with(:name => 'Aaron')).new
+    aaron = PoorDeveloperCalledJamis.create_with(name: "foo", salary: 20).merge(
+      PoorDeveloperCalledJamis.create_with(name: "Aaron")).new
     assert_equal 20, aaron.salary
-    assert_equal 'Aaron', aaron.name
+    assert_equal "Aaron", aaron.name
 
-    aaron = PoorDeveloperCalledJamis.create_with(:name => 'foo', :salary => 20).
-                                     create_with(:name => 'Aaron').new
+    aaron = PoorDeveloperCalledJamis.create_with(name: "foo", salary: 20).
+                                     create_with(name: "Aaron").new
     assert_equal 20, aaron.salary
-    assert_equal 'Aaron', aaron.name
+    assert_equal "Aaron", aaron.name
+  end
+
+  def test_create_with_using_both_string_and_symbol
+    jamis = PoorDeveloperCalledJamis.create_with(name: "foo").create_with("name" => "Aaron").new
+    assert_equal "Aaron", jamis.name
   end
 
   def test_create_with_reset
-    jamis = PoorDeveloperCalledJamis.create_with(:name => 'Aaron').create_with(nil).new
-    assert_equal 'Jamis', jamis.name
+    jamis = PoorDeveloperCalledJamis.create_with(name: "Aaron").create_with(nil).new
+    assert_equal "Jamis", jamis.name
   end
 
   # FIXME: I don't know if this is *desired* behavior, but it is *today's*
   # behavior.
   def test_create_with_empty_hash_will_not_reset
-    jamis = PoorDeveloperCalledJamis.create_with(:name => 'Aaron').create_with({}).new
-    assert_equal 'Aaron', jamis.name
+    jamis = PoorDeveloperCalledJamis.create_with(name: "Aaron").create_with({}).new
+    assert_equal "Aaron", jamis.name
   end
 
   def test_unscoped_with_named_scope_should_not_have_default_scope
     assert_equal [DeveloperCalledJamis.find(developers(:poor_jamis).id)], DeveloperCalledJamis.poor
 
-    assert DeveloperCalledJamis.unscoped.poor.include?(developers(:david).becomes(DeveloperCalledJamis))
+    assert_includes DeveloperCalledJamis.unscoped.poor, developers(:david).becomes(DeveloperCalledJamis)
 
     assert_equal 11, DeveloperCalledJamis.unscoped.length
     assert_equal 1,  DeveloperCalledJamis.poor.length
@@ -382,11 +379,39 @@ class DefaultScopingTest < ActiveRecord::TestCase
                  Comment.joins(:post).count
   end
 
+  def test_joins_not_affected_by_scope_other_than_default_or_unscoped
+    without_scope_on_post = Comment.joins(:post).to_a
+    with_scope_on_post = nil
+    Post.where(id: [1, 5, 6]).scoping do
+      with_scope_on_post = Comment.joins(:post).to_a
+    end
+
+    assert_equal with_scope_on_post, without_scope_on_post
+  end
+
   def test_unscoped_with_joins_should_not_have_default_scope
     assert_equal SpecialPostWithDefaultScope.unscoped { Comment.joins(:special_post_with_default_scope).to_a },
                  Comment.joins(:post).to_a
   end
 
+  def test_sti_association_with_unscoped_not_affected_by_default_scope
+    post = posts(:thinking)
+    comments = [comments(:does_it_hurt)]
+
+    post.special_comments.update_all(deleted_at: Time.now)
+
+    assert_raises(ActiveRecord::RecordNotFound) { Post.joins(:special_comments).find(post.id) }
+    assert_equal [], post.special_comments
+
+    SpecialComment.unscoped do
+      assert_equal post, Post.joins(:special_comments).find(post.id)
+      assert_equal comments, Post.joins(:special_comments).find(post.id).special_comments
+      assert_equal comments, Post.eager_load(:special_comments).find(post.id).special_comments
+      assert_equal comments, Post.includes(:special_comments).find(post.id).special_comments
+      assert_equal comments, Post.preload(:special_comments).find(post.id).special_comments
+    end
+  end
+
   def test_default_scope_select_ignored_by_aggregations
     assert_equal DeveloperWithSelect.all.to_a.count, DeveloperWithSelect.count
   end
@@ -409,9 +434,9 @@ class DefaultScopingTest < ActiveRecord::TestCase
 
   def test_default_scope_include_with_count
     d = DeveloperWithIncludes.create!
-    d.audit_logs.create! :message => 'foo'
+    d.audit_logs.create! message: "foo"
 
-    assert_equal 1, DeveloperWithIncludes.where(:audit_logs => { :message => 'foo' }).count
+    assert_equal 1, DeveloperWithIncludes.where(audit_logs: { message: "foo" }).count
   end
 
   def test_default_scope_with_references_works_through_collection_association
@@ -432,24 +457,6 @@ class DefaultScopingTest < ActiveRecord::TestCase
     assert_equal comment, CommentWithDefaultScopeReferencesAssociation.find_by(id: comment.id)
   end
 
-  unless in_memory_db?
-    def test_default_scope_is_threadsafe
-      threads = []
-      assert_not_equal 1, ThreadsafeDeveloper.unscoped.count
-
-      threads << Thread.new do
-        Thread.current[:long_default_scope] = true
-        assert_equal 1, ThreadsafeDeveloper.all.to_a.count
-        ThreadsafeDeveloper.connection.close
-      end
-      threads << Thread.new do
-        assert_equal 1, ThreadsafeDeveloper.all.to_a.count
-        ThreadsafeDeveloper.connection.close
-      end
-      threads.each(&:join)
-    end
-  end
-
   test "additional conditions are ANDed with the default scope" do
     scope = DeveloperCalledJamis.where(name: "David")
     assert_equal 2, scope.where_clause.ast.children.length
@@ -465,7 +472,7 @@ class DefaultScopingTest < ActiveRecord::TestCase
   test "a scope can remove the condition from the default scope" do
     scope = DeveloperCalledJamis.david2
     assert_equal 1, scope.where_clause.ast.children.length
-    assert_equal Developer.where(name: "David"), scope
+    assert_equal Developer.where(name: "David").map(&:id), scope.map(&:id)
   end
 
   def test_with_abstract_class_where_clause_should_not_be_duplicated
@@ -474,9 +481,9 @@ class DefaultScopingTest < ActiveRecord::TestCase
   end
 
   def test_sti_conditions_are_not_carried_in_default_scope
-    ConditionalStiPost.create! body: ''
-    SubConditionalStiPost.create! body: ''
-    SubConditionalStiPost.create! title: 'Hello world', body: ''
+    ConditionalStiPost.create! body: ""
+    SubConditionalStiPost.create! body: ""
+    SubConditionalStiPost.create! title: "Hello world", body: ""
 
     assert_equal 2, ConditionalStiPost.count
     assert_equal 2, ConditionalStiPost.all.to_a.size
@@ -490,6 +497,8 @@ class DefaultScopingTest < ActiveRecord::TestCase
   def test_with_abstract_class_scope_should_be_executed_in_correct_context
     vegetarian_pattern, gender_pattern = if current_adapter?(:Mysql2Adapter)
       [/`lions`.`is_vegetarian`/, /`lions`.`gender`/]
+    elsif current_adapter?(:OracleAdapter)
+      [/"LIONS"."IS_VEGETARIAN"/, /"LIONS"."GENDER"/]
     else
       [/"lions"."is_vegetarian"/, /"lions"."gender"/]
     end
@@ -498,3 +507,41 @@ class DefaultScopingTest < ActiveRecord::TestCase
     assert_match gender_pattern, Lion.female.to_sql
   end
 end
+
+class DefaultScopingWithThreadTest < ActiveRecord::TestCase
+  self.use_transactional_tests = false
+
+  def test_default_scoping_with_threads
+    2.times do
+      Thread.new {
+        assert_includes DeveloperOrderedBySalary.all.to_sql, "salary DESC"
+        DeveloperOrderedBySalary.connection.close
+      }.join
+    end
+  end
+
+  def test_default_scope_is_threadsafe
+    2.times { ThreadsafeDeveloper.unscoped.create! }
+
+    threads = []
+    assert_not_equal 1, ThreadsafeDeveloper.unscoped.count
+
+    barrier_1 = Concurrent::CyclicBarrier.new(2)
+    barrier_2 = Concurrent::CyclicBarrier.new(2)
+
+    threads << Thread.new do
+      Thread.current[:default_scope_delay] = -> { barrier_1.wait; barrier_2.wait }
+      assert_equal 1, ThreadsafeDeveloper.all.to_a.count
+      ThreadsafeDeveloper.connection.close
+    end
+    threads << Thread.new do
+      Thread.current[:default_scope_delay] = -> { barrier_2.wait }
+      barrier_1.wait
+      assert_equal 1, ThreadsafeDeveloper.all.to_a.count
+      ThreadsafeDeveloper.connection.close
+    end
+    threads.each(&:join)
+  ensure
+    ThreadsafeDeveloper.unscoped.destroy_all
+  end
+end unless in_memory_db?
diff --git a/activerecord/test/cases/scoping/named_scoping_test.rb b/activerecord/test/cases/scoping/named_scoping_test.rb
index 0e277ed235..17d3f27bb1 100644
--- a/activerecord/test/cases/scoping/named_scoping_test.rb
+++ b/activerecord/test/cases/scoping/named_scoping_test.rb
@@ -1,11 +1,13 @@
+# frozen_string_literal: true
+
 require "cases/helper"
-require 'models/post'
-require 'models/topic'
-require 'models/comment'
-require 'models/reply'
-require 'models/author'
-require 'models/developer'
-require 'models/computer'
+require "models/post"
+require "models/topic"
+require "models/comment"
+require "models/reply"
+require "models/author"
+require "models/developer"
+require "models/computer"
 
 class NamedScopingTest < ActiveRecord::TestCase
   fixtures :posts, :authors, :topics, :comments, :author_addresses
@@ -23,8 +25,8 @@ class NamedScopingTest < ActiveRecord::TestCase
     all_posts = Topic.base
 
     assert_queries(1) do
-      all_posts.collect
-      all_posts.collect
+      all_posts.collect { true }
+      all_posts.collect { true }
     end
   end
 
@@ -33,8 +35,8 @@ class NamedScopingTest < ActiveRecord::TestCase
     all_posts.to_a
 
     new_post = Topic.create!
-    assert !all_posts.include?(new_post)
-    assert all_posts.reload.include?(new_post)
+    assert_not_includes all_posts, new_post
+    assert_includes all_posts.reload, new_post
   end
 
   def test_delegates_finds_and_calculations_to_the_base_class
@@ -46,11 +48,18 @@ class NamedScopingTest < ActiveRecord::TestCase
     assert_equal Topic.average(:replies_count), Topic.base.average(:replies_count)
   end
 
+  def test_calling_merge_at_first_in_scope
+    Topic.class_eval do
+      scope :calling_merge_at_first_in_scope, Proc.new { merge(Topic.replied) }
+    end
+    assert_equal Topic.calling_merge_at_first_in_scope.to_a, Topic.replied.to_a
+  end
+
   def test_method_missing_priority_when_delegating
     klazz = Class.new(ActiveRecord::Base) do
       self.table_name = "topics"
-      scope :since, Proc.new { where('written_on >= ?', Time.now - 1.day) }
-      scope :to,    Proc.new { where('written_on <= ?', Time.now) }
+      scope :since, Proc.new { where("written_on >= ?", Time.now - 1.day) }
+      scope :to,    Proc.new { where("written_on <= ?", Time.now) }
     end
     assert_equal klazz.to.since.to_a, klazz.since.to.to_a
   end
@@ -62,10 +71,10 @@ class NamedScopingTest < ActiveRecord::TestCase
   end
 
   def test_scopes_with_options_limit_finds_to_those_matching_the_criteria_specified
-    assert !Topic.all.merge!(:where => {:approved => true}).to_a.empty?
+    assert !Topic.all.merge!(where: { approved: true }).to_a.empty?
 
-    assert_equal Topic.all.merge!(:where => {:approved => true}).to_a, Topic.approved
-    assert_equal Topic.where(:approved => true).count, Topic.approved.count
+    assert_equal Topic.all.merge!(where: { approved: true }).to_a, Topic.approved
+    assert_equal Topic.where(approved: true).count, Topic.approved.count
   end
 
   def test_scopes_with_string_name_can_be_composed
@@ -75,8 +84,8 @@ class NamedScopingTest < ActiveRecord::TestCase
   end
 
   def test_scopes_are_composable
-    assert_equal((approved = Topic.all.merge!(:where => {:approved => true}).to_a), Topic.approved)
-    assert_equal((replied = Topic.all.merge!(:where => 'replies_count > 0').to_a), Topic.replied)
+    assert_equal((approved = Topic.all.merge!(where: { approved: true }).to_a), Topic.approved)
+    assert_equal((replied = Topic.all.merge!(where: "replies_count > 0").to_a), Topic.replied)
     assert !(approved == replied)
     assert !(approved & replied).empty?
 
@@ -84,8 +93,8 @@ class NamedScopingTest < ActiveRecord::TestCase
   end
 
   def test_procedural_scopes
-    topics_written_before_the_third = Topic.where('written_on < ?', topics(:third).written_on)
-    topics_written_before_the_second = Topic.where('written_on < ?', topics(:second).written_on)
+    topics_written_before_the_third = Topic.where("written_on < ?", topics(:third).written_on)
+    topics_written_before_the_second = Topic.where("written_on < ?", topics(:second).written_on)
     assert_not_equal topics_written_before_the_second, topics_written_before_the_third
 
     assert_equal topics_written_before_the_third, Topic.written_before(topics(:third).written_on)
@@ -101,26 +110,28 @@ class NamedScopingTest < ActiveRecord::TestCase
   def test_scope_with_object
     objects = Topic.with_object
     assert_operator objects.length, :>, 0
-    assert objects.all?(&:approved?), 'all objects should be approved'
+    assert objects.all?(&:approved?), "all objects should be approved"
   end
 
   def test_has_many_associations_have_access_to_scopes
     assert_not_equal Post.containing_the_letter_a, authors(:david).posts
     assert !Post.containing_the_letter_a.empty?
 
-    assert_equal authors(:david).posts & Post.containing_the_letter_a, authors(:david).posts.containing_the_letter_a
+    expected = authors(:david).posts & Post.containing_the_letter_a
+    assert_equal expected.sort_by(&:id), authors(:david).posts.containing_the_letter_a.sort_by(&:id)
   end
 
   def test_scope_with_STI
-    assert_equal 3,Post.containing_the_letter_a.count
-    assert_equal 1,SpecialPost.containing_the_letter_a.count
+    assert_equal 3, Post.containing_the_letter_a.count
+    assert_equal 1, SpecialPost.containing_the_letter_a.count
   end
 
   def test_has_many_through_associations_have_access_to_scopes
     assert_not_equal Comment.containing_the_letter_e, authors(:david).comments
     assert !Comment.containing_the_letter_e.empty?
 
-    assert_equal authors(:david).comments & Comment.containing_the_letter_e, authors(:david).comments.containing_the_letter_e
+    expected = authors(:david).comments & Comment.containing_the_letter_e
+    assert_equal expected.sort_by(&:id), authors(:david).comments.containing_the_letter_e.sort_by(&:id)
   end
 
   def test_scopes_honor_current_scopes_from_when_defined
@@ -140,6 +151,22 @@ class NamedScopingTest < ActiveRecord::TestCase
     assert_equal "The scope body needs to be callable.", e.message
   end
 
+  def test_scopes_name_is_relation_method
+    conflicts = [
+      :records,
+      :to_ary,
+      :to_sql,
+      :explain
+    ]
+
+    conflicts.each do |name|
+      e = assert_raises ArgumentError do
+        Class.new(Post).class_eval { scope name, -> { where(approved: true) } }
+      end
+      assert_match(/You tried to define a scope named \"#{name}\" on the model/, e.message)
+    end
+  end
+
   def test_active_records_have_scope_named__all__
     assert !Topic.all.empty?
 
@@ -154,13 +181,13 @@ class NamedScopingTest < ActiveRecord::TestCase
   end
 
   def test_first_and_last_should_allow_integers_for_limit
-    assert_equal Topic.base.first(2), Topic.base.to_a.first(2)
+    assert_equal Topic.base.first(2), Topic.base.order("id").to_a.first(2)
     assert_equal Topic.base.last(2), Topic.base.order("id").to_a.last(2)
   end
 
   def test_first_and_last_should_not_use_query_when_results_are_loaded
     topics = Topic.base
-    topics.reload # force load
+    topics.load # force load
     assert_no_queries do
       topics.first
       topics.last
@@ -171,7 +198,7 @@ class NamedScopingTest < ActiveRecord::TestCase
     topics = Topic.base
     assert_queries(2) do
       topics.empty?  # use count query
-      topics.collect # force load
+      topics.load    # force load
       topics.empty?  # use loaded (no query)
     end
   end
@@ -180,7 +207,7 @@ class NamedScopingTest < ActiveRecord::TestCase
     topics = Topic.base
     assert_queries(2) do
       topics.any?    # use count query
-      topics.collect # force load
+      topics.load    # force load
       topics.any?    # use loaded (no query)
     end
   end
@@ -196,7 +223,7 @@ class NamedScopingTest < ActiveRecord::TestCase
 
   def test_any_should_not_fire_query_if_scope_loaded
     topics = Topic.base
-    topics.collect # force load
+    topics.load # force load
     assert_no_queries { assert topics.any? }
   end
 
@@ -210,7 +237,7 @@ class NamedScopingTest < ActiveRecord::TestCase
     topics = Topic.base
     assert_queries(2) do
       topics.many?   # use count query
-      topics.collect # force load
+      topics.load    # force load
       topics.many?   # use loaded (no query)
     end
   end
@@ -226,14 +253,14 @@ class NamedScopingTest < ActiveRecord::TestCase
 
   def test_many_should_not_fire_query_if_scope_loaded
     topics = Topic.base
-    topics.collect # force load
+    topics.load # force load
     assert_no_queries { assert topics.many? }
   end
 
   def test_many_should_return_false_if_none_or_one
-    topics = Topic.base.where(:id => 0)
+    topics = Topic.base.where(id: 0)
     assert !topics.many?
-    topics = Topic.base.where(:id => 1)
+    topics = Topic.base.where(id: 1)
     assert !topics.many?
   end
 
@@ -273,7 +300,7 @@ class NamedScopingTest < ActiveRecord::TestCase
   def test_should_build_on_top_of_chained_scopes
     topic = Topic.approved.by_lifo.build({})
     assert topic.approved
-    assert_equal 'lifo', topic.author_name
+    assert_equal "lifo", topic.author_name
   end
 
   def test_reserved_scope_names
@@ -320,12 +347,12 @@ class NamedScopingTest < ActiveRecord::TestCase
 
     conflicts.each do |name|
       e = assert_raises(ArgumentError, "scope `#{name}` should not be allowed") do
-        klass.class_eval { scope name, ->{ where(approved: true) } }
+        klass.class_eval { scope name, -> { where(approved: true) } }
       end
       assert_match(/You tried to define a scope named \"#{name}\" on the model/, e.message)
 
       e = assert_raises(ArgumentError, "scope `#{name}` should not be allowed") do
-        subklass.class_eval { scope name, ->{ where(approved: true) } }
+        subklass.class_eval { scope name, -> { where(approved: true) } }
       end
       assert_match(/You tried to define a scope named \"#{name}\" on the model/, e.message)
     end
@@ -333,12 +360,12 @@ class NamedScopingTest < ActiveRecord::TestCase
     non_conflicts.each do |name|
       assert_nothing_raised do
         silence_warnings do
-          klass.class_eval { scope name, ->{ where(approved: true) } }
+          klass.class_eval { scope name, -> { where(approved: true) } }
         end
       end
 
       assert_nothing_raised do
-        subklass.class_eval { scope name, ->{ where(approved: true) } }
+        subklass.class_eval { scope name, -> { where(approved: true) } }
       end
     end
   end
@@ -350,7 +377,7 @@ class NamedScopingTest < ActiveRecord::TestCase
     klass = Class.new(ActiveRecord::Base) do
       self.table_name = "topics"
       scope :"title containing space", -> { where("title LIKE '% %'") }
-      scope :approved, -> { where(:approved => true) }
+      scope :approved, -> { where(approved: true) }
     end
     assert_equal klass.send(:"title containing space"), klass.where("title LIKE '% %'")
     assert_equal klass.approved.send(:"title containing space"), klass.approved.where("title LIKE '% %'")
@@ -365,7 +392,7 @@ class NamedScopingTest < ActiveRecord::TestCase
   end
 
   def test_should_use_where_in_query_for_scope
-    assert_equal Developer.where(name: 'Jamis').to_set, Developer.where(id: Developer.jamises).to_set
+    assert_equal Developer.where(name: "Jamis").to_set, Developer.where(id: Developer.jamises).to_set
   end
 
   def test_size_should_use_count_when_results_are_not_loaded
@@ -377,7 +404,7 @@ class NamedScopingTest < ActiveRecord::TestCase
 
   def test_size_should_use_length_when_results_are_loaded
     topics = Topic.base
-    topics.reload # force load
+    topics.load # force load
     assert_no_queries do
       topics.size # use loaded (no query)
     end
@@ -424,12 +451,12 @@ class NamedScopingTest < ActiveRecord::TestCase
     assert_equal 4, Topic.approved.count
 
     assert_queries(5) do
-      Topic.approved.find_each(:batch_size => 1) {|t| assert t.approved? }
+      Topic.approved.find_each(batch_size: 1) { |t| assert t.approved? }
     end
 
     assert_queries(3) do
-      Topic.approved.find_in_batches(:batch_size => 2) do |group|
-        group.each {|t| assert t.approved? }
+      Topic.approved.find_in_batches(batch_size: 2) do |group|
+        group.each { |t| assert t.approved? }
       end
     end
   end
@@ -455,13 +482,13 @@ class NamedScopingTest < ActiveRecord::TestCase
     [:public_method, :protected_method, :private_method].each do |reserved_method|
       assert Topic.respond_to?(reserved_method, true)
       ActiveRecord::Base.logger.expects(:warn)
-      silence_warnings { Topic.scope(reserved_method, -> { }) }
+      silence_warnings { Topic.scope(reserved_method, -> {}) }
     end
   end
 
   def test_scopes_on_relations
     # Topic.replied
-    approved_topics = Topic.all.approved.order('id DESC')
+    approved_topics = Topic.all.approved.order("id DESC")
     assert_equal topics(:fifth), approved_topics.first
 
     replied_approved_topics = approved_topics.replied
@@ -469,7 +496,7 @@ class NamedScopingTest < ActiveRecord::TestCase
   end
 
   def test_index_on_scope
-    approved = Topic.approved.order('id ASC')
+    approved = Topic.approved.order("id ASC")
     assert_equal topics(:second), approved[0]
     assert approved.loaded?
   end
@@ -510,7 +537,7 @@ class NamedScopingTest < ActiveRecord::TestCase
   def test_scopes_to_get_newest
     post = posts(:welcome)
     old_last_comment = post.comments.newest
-    new_comment = post.comments.create(:body => "My new comment")
+    new_comment = post.comments.create(body: "My new comment")
     assert_equal new_comment, post.comments.newest
     assert_not_equal old_last_comment, post.comments.newest
   end
@@ -533,15 +560,21 @@ class NamedScopingTest < ActiveRecord::TestCase
 
   def test_eager_default_scope_relations_are_remove
     klass = Class.new(ActiveRecord::Base)
-    klass.table_name = 'posts'
+    klass.table_name = "posts"
 
     assert_raises(ArgumentError) do
-      klass.send(:default_scope, klass.where(:id => posts(:welcome).id))
+      klass.send(:default_scope, klass.where(id: posts(:welcome).id))
     end
   end
 
   def test_subclass_merges_scopes_properly
-    assert_equal 1, SpecialComment.where(body: 'go crazy').created.count
+    assert_equal 1, SpecialComment.where(body: "go crazy").created.count
+  end
+
+  def test_model_class_should_respond_to_extending
+    assert_raises OopsError do
+      Comment.unscoped.oops_comments.destroy_all
+    end
   end
 
   def test_model_class_should_respond_to_none
@@ -557,5 +590,4 @@ class NamedScopingTest < ActiveRecord::TestCase
     Topic.create!
     assert Topic.one?
   end
-
 end
diff --git a/activerecord/test/cases/scoping/relation_scoping_test.rb b/activerecord/test/cases/scoping/relation_scoping_test.rb
index c15d57460b..116f8e83aa 100644
--- a/activerecord/test/cases/scoping/relation_scoping_test.rb
+++ b/activerecord/test/cases/scoping/relation_scoping_test.rb
@@ -1,16 +1,18 @@
+# frozen_string_literal: true
+
 require "cases/helper"
-require 'models/post'
-require 'models/author'
-require 'models/developer'
-require 'models/computer'
-require 'models/project'
-require 'models/comment'
-require 'models/category'
-require 'models/person'
-require 'models/reference'
+require "models/post"
+require "models/author"
+require "models/developer"
+require "models/computer"
+require "models/project"
+require "models/comment"
+require "models/category"
+require "models/person"
+require "models/reference"
 
 class RelationScopingTest < ActiveRecord::TestCase
-  fixtures :authors, :developers, :projects, :comments, :posts, :developers_projects
+  fixtures :authors, :author_addresses, :developers, :projects, :comments, :posts, :developers_projects
 
   setup do
     developers(:david)
@@ -28,7 +30,7 @@ class RelationScopingTest < ActiveRecord::TestCase
   def test_scope_breaks_caching_on_collections
     author = authors :david
     ids = author.reload.special_posts_with_default_scope.map(&:id)
-    assert_equal [1,5,6], ids.sort
+    assert_equal [1, 5, 6], ids.sort
     scoped_posts = SpecialPostWithDefaultScope.unscoped do
       author = authors :david
       author.reload.special_posts_with_default_scope.to_a
@@ -109,7 +111,7 @@ class RelationScopingTest < ActiveRecord::TestCase
 
   def test_scope_select_concatenates
     Developer.select("id, name").scoping do
-      developer = Developer.select('salary').where("name = 'David'").first
+      developer = Developer.select("salary").where("name = 'David'").first
       assert_equal 80000, developer.salary
       assert developer.has_attribute?(:id)
       assert developer.has_attribute?(:name)
@@ -122,7 +124,7 @@ class RelationScopingTest < ActiveRecord::TestCase
       assert_equal 1, Developer.count
     end
 
-    Developer.where('salary = 100000').scoping do
+    Developer.where("salary = 100000").scoping do
       assert_equal 8, Developer.count
       assert_equal 1, Developer.where("name LIKE 'fixture_1%'").count
     end
@@ -131,49 +133,49 @@ class RelationScopingTest < ActiveRecord::TestCase
   def test_scoped_find_include
     # with the include, will retrieve only developers for the given project
     scoped_developers = Developer.includes(:projects).scoping do
-      Developer.where('projects.id' => 2).to_a
+      Developer.where("projects.id" => 2).to_a
     end
-    assert scoped_developers.include?(developers(:david))
-    assert !scoped_developers.include?(developers(:jamis))
+    assert_includes scoped_developers, developers(:david)
+    assert_not_includes scoped_developers, developers(:jamis)
     assert_equal 1, scoped_developers.size
   end
 
   def test_scoped_find_joins
-    scoped_developers = Developer.joins('JOIN developers_projects ON id = developer_id').scoping do
-      Developer.where('developers_projects.project_id = 2').to_a
+    scoped_developers = Developer.joins("JOIN developers_projects ON id = developer_id").scoping do
+      Developer.where("developers_projects.project_id = 2").to_a
     end
 
-    assert scoped_developers.include?(developers(:david))
-    assert !scoped_developers.include?(developers(:jamis))
+    assert_includes scoped_developers, developers(:david)
+    assert_not_includes scoped_developers, developers(:jamis)
     assert_equal 1, scoped_developers.size
     assert_equal developers(:david).attributes, scoped_developers.first.attributes
   end
 
   def test_scoped_create_with_where
-    new_comment = VerySpecialComment.where(:post_id => 1).scoping do
-      VerySpecialComment.create :body => "Wonderful world"
+    new_comment = VerySpecialComment.where(post_id: 1).scoping do
+      VerySpecialComment.create body: "Wonderful world"
     end
 
     assert_equal 1, new_comment.post_id
-    assert Post.find(1).comments.include?(new_comment)
+    assert_includes Post.find(1).comments, new_comment
   end
 
   def test_scoped_create_with_create_with
-    new_comment = VerySpecialComment.create_with(:post_id => 1).scoping do
-      VerySpecialComment.create :body => "Wonderful world"
+    new_comment = VerySpecialComment.create_with(post_id: 1).scoping do
+      VerySpecialComment.create body: "Wonderful world"
     end
 
     assert_equal 1, new_comment.post_id
-    assert Post.find(1).comments.include?(new_comment)
+    assert_includes Post.find(1).comments, new_comment
   end
 
   def test_scoped_create_with_create_with_has_higher_priority
-    new_comment = VerySpecialComment.where(:post_id => 2).create_with(:post_id => 1).scoping do
-      VerySpecialComment.create :body => "Wonderful world"
+    new_comment = VerySpecialComment.where(post_id: 2).create_with(post_id: 1).scoping do
+      VerySpecialComment.create body: "Wonderful world"
     end
 
     assert_equal 1, new_comment.post_id
-    assert Post.find(1).comments.include?(new_comment)
+    assert_includes Post.find(1).comments, new_comment
   end
 
   def test_ensure_that_method_scoping_is_correctly_restored
@@ -193,7 +195,7 @@ class RelationScopingTest < ActiveRecord::TestCase
   end
 
   def test_update_all_default_scope_filters_on_joins
-    DeveloperFilteredOnJoins.update_all(:salary => 65000)
+    DeveloperFilteredOnJoins.update_all(salary: 65000)
     assert_equal 65000, Developer.find(developers(:david).id).salary
 
     # has not changed jamis
@@ -228,18 +230,55 @@ class RelationScopingTest < ActiveRecord::TestCase
       assert SpecialComment.all.any?
     end
   end
+
+  def test_scoping_is_correctly_restored
+    Comment.unscoped do
+      SpecialComment.unscoped.created
+    end
+
+    assert_nil Comment.current_scope
+    assert_nil SpecialComment.current_scope
+  end
+
+  def test_scoping_respects_current_class
+    Comment.unscoped do
+      assert_equal "a comment...", Comment.all.what_are_you
+      assert_equal "a special comment...", SpecialComment.all.what_are_you
+    end
+  end
+
+  def test_scoping_respects_sti_constraint
+    Comment.unscoped do
+      assert_equal comments(:greetings), Comment.find(1)
+      assert_raises(ActiveRecord::RecordNotFound) { SpecialComment.find(1) }
+    end
+  end
+
+  def test_circular_joins_with_scoping_does_not_crash
+    posts = Post.joins(comments: :post).scoping do
+      Post.first(10)
+    end
+    assert_equal posts, Post.joins(comments: :post).first(10)
+  end
+
+  def test_circular_left_joins_with_scoping_does_not_crash
+    posts = Post.left_joins(comments: :post).scoping do
+      Post.first(10)
+    end
+    assert_equal posts, Post.left_joins(comments: :post).first(10)
+  end
 end
 
 class NestedRelationScopingTest < ActiveRecord::TestCase
-  fixtures :authors, :developers, :projects, :comments, :posts
+  fixtures :authors, :author_addresses, :developers, :projects, :comments, :posts
 
   def test_merge_options
-    Developer.where('salary = 80000').scoping do
+    Developer.where("salary = 80000").scoping do
       Developer.limit(10).scoping do
         devs = Developer.all
         sql = devs.to_sql
-        assert_match '(salary = 80000)', sql
-        assert_match 'LIMIT 10', sql
+        assert_match "(salary = 80000)", sql
+        assert_match(/LIMIT 10|ROWNUM <= 10|FETCH FIRST 10 ROWS ONLY/, sql)
       end
     end
   end
@@ -253,39 +292,39 @@ class NestedRelationScopingTest < ActiveRecord::TestCase
   end
 
   def test_replace_options
-    Developer.where(:name => 'David').scoping do
+    Developer.where(name: "David").scoping do
       Developer.unscoped do
-        assert_equal 'Jamis', Developer.where(:name => 'Jamis').first[:name]
+        assert_equal "Jamis", Developer.where(name: "Jamis").first[:name]
       end
 
-      assert_equal 'David', Developer.first[:name]
+      assert_equal "David", Developer.first[:name]
     end
   end
 
   def test_three_level_nested_exclusive_scoped_find
     Developer.where("name = 'Jamis'").scoping do
-      assert_equal 'Jamis', Developer.first.name
+      assert_equal "Jamis", Developer.first.name
 
       Developer.unscoped.where("name = 'David'") do
-        assert_equal 'David', Developer.first.name
+        assert_equal "David", Developer.first.name
 
         Developer.unscoped.where("name = 'Maiha'") do
-          assert_equal nil, Developer.first
+          assert_nil Developer.first
         end
 
         # ensure that scoping is restored
-        assert_equal 'David', Developer.first.name
+        assert_equal "David", Developer.first.name
       end
 
       # ensure that scoping is restored
-      assert_equal 'Jamis', Developer.first.name
+      assert_equal "Jamis", Developer.first.name
     end
   end
 
   def test_nested_scoped_create
-    comment = Comment.create_with(:post_id => 1).scoping do
-      Comment.create_with(:post_id => 2).scoping do
-        Comment.create :body => "Hey guys, nested scopes are broken. Please fix!"
+    comment = Comment.create_with(post_id: 1).scoping do
+      Comment.create_with(post_id: 2).scoping do
+        Comment.create body: "Hey guys, nested scopes are broken. Please fix!"
       end
     end
 
@@ -293,15 +332,15 @@ class NestedRelationScopingTest < ActiveRecord::TestCase
   end
 
   def test_nested_exclusive_scope_for_create
-    comment = Comment.create_with(:body => "Hey guys, nested scopes are broken. Please fix!").scoping do
-      Comment.unscoped.create_with(:post_id => 1).scoping do
+    comment = Comment.create_with(body: "Hey guys, nested scopes are broken. Please fix!").scoping do
+      Comment.unscoped.create_with(post_id: 1).scoping do
         assert Comment.new.body.blank?
-        Comment.create :body => "Hey guys"
+        Comment.create body: "Hey guys"
       end
     end
 
     assert_equal 1, comment.post_id
-    assert_equal 'Hey guys', comment.body
+    assert_equal "Hey guys", comment.body
   end
 end
 
@@ -313,24 +352,24 @@ class HasManyScopingTest < ActiveRecord::TestCase
   end
 
   def test_forwarding_of_static_methods
-    assert_equal 'a comment...', Comment.what_are_you
-    assert_equal 'a comment...', @welcome.comments.what_are_you
+    assert_equal "a comment...", Comment.what_are_you
+    assert_equal "a comment...", @welcome.comments.what_are_you
   end
 
   def test_forwarding_to_scoped
-    assert_equal 4, Comment.search_by_type('Comment').size
-    assert_equal 2, @welcome.comments.search_by_type('Comment').size
+    assert_equal 4, Comment.search_by_type("Comment").size
+    assert_equal 2, @welcome.comments.search_by_type("Comment").size
   end
 
   def test_nested_scope_finder
-    Comment.where('1=0').scoping do
+    Comment.where("1=0").scoping do
       assert_equal 0, @welcome.comments.count
-      assert_equal 'a comment...', @welcome.comments.what_are_you
+      assert_equal "a comment...", @welcome.comments.what_are_you
     end
 
-    Comment.where('1=1').scoping do
+    Comment.where("1=1").scoping do
       assert_equal 2, @welcome.comments.count
-      assert_equal 'a comment...', @welcome.comments.what_are_you
+      assert_equal "a comment...", @welcome.comments.what_are_you
     end
   end
 
@@ -345,7 +384,7 @@ class HasManyScopingTest < ActiveRecord::TestCase
   end
 
   def test_should_maintain_default_scope_on_eager_loaded_associations
-    michael = Person.where(:id => people(:michael).id).includes(:bad_references).first
+    michael = Person.where(id: people(:michael).id).includes(:bad_references).first
     magician = BadReference.find(1)
     assert_equal [magician], michael.bad_references
   end
@@ -359,19 +398,19 @@ class HasAndBelongsToManyScopingTest < ActiveRecord::TestCase
   end
 
   def test_forwarding_of_static_methods
-    assert_equal 'a category...', Category.what_are_you
-    assert_equal 'a category...', @welcome.categories.what_are_you
+    assert_equal "a category...", Category.what_are_you
+    assert_equal "a category...", @welcome.categories.what_are_you
   end
 
   def test_nested_scope_finder
-    Category.where('1=0').scoping do
+    Category.where("1=0").scoping do
       assert_equal 0, @welcome.categories.count
-      assert_equal 'a category...', @welcome.categories.what_are_you
+      assert_equal "a category...", @welcome.categories.what_are_you
     end
 
-    Category.where('1=1').scoping do
+    Category.where("1=1").scoping do
       assert_equal 2, @welcome.categories.count
-      assert_equal 'a category...', @welcome.categories.what_are_you
+      assert_equal "a category...", @welcome.categories.what_are_you
     end
   end
 end
diff --git a/activerecord/test/cases/secure_token_test.rb b/activerecord/test/cases/secure_token_test.rb
index e731443fc2..f5fa6aa302 100644
--- a/activerecord/test/cases/secure_token_test.rb
+++ b/activerecord/test/cases/secure_token_test.rb
@@ -1,5 +1,7 @@
-require 'cases/helper'
-require 'models/user'
+# frozen_string_literal: true
+
+require "cases/helper"
+require "models/user"
 
 class SecureTokenTest < ActiveRecord::TestCase
   setup do
@@ -27,6 +29,6 @@ class SecureTokenTest < ActiveRecord::TestCase
     @user.token = "custom-secure-token"
     @user.save
 
-    assert_equal @user.token, "custom-secure-token"
+    assert_equal "custom-secure-token", @user.token
   end
 end
diff --git a/activerecord/test/cases/serialization_test.rb b/activerecord/test/cases/serialization_test.rb
index 14b80f4df4..2d829ad4ba 100644
--- a/activerecord/test/cases/serialization_test.rb
+++ b/activerecord/test/cases/serialization_test.rb
@@ -1,9 +1,11 @@
+# frozen_string_literal: true
+
 require "cases/helper"
-require 'models/contact'
-require 'models/topic'
-require 'models/book'
-require 'models/author'
-require 'models/post'
+require "models/contact"
+require "models/topic"
+require "models/book"
+require "models/author"
+require "models/post"
 
 class SerializationTest < ActiveRecord::TestCase
   fixtures :books
@@ -12,14 +14,14 @@ class SerializationTest < ActiveRecord::TestCase
 
   def setup
     @contact_attributes = {
-      :name           => 'aaron stack',
-      :age            => 25,
-      :avatar         => 'binarydata',
-      :created_at     => Time.utc(2006, 8, 1),
-      :awesome        => false,
-      :preferences    => { :gem => '<strong>ruby</strong>' },
-      :alternative_id => nil,
-      :id             => nil
+      name: "aaron stack",
+      age: 25,
+      avatar: "binarydata",
+      created_at: Time.utc(2006, 8, 1),
+      awesome: false,
+      preferences: { gem: "<strong>ruby</strong>" },
+      alternative_id: nil,
+      id: nil
     }
   end
 
@@ -38,7 +40,7 @@ class SerializationTest < ActiveRecord::TestCase
 
   def test_serialize_should_allow_attribute_only_filtering
     FORMATS.each do |format|
-      @serialized = Contact.new(@contact_attributes).send("to_#{format}", :only => [ :age, :name ])
+      @serialized = Contact.new(@contact_attributes).send("to_#{format}", only: [ :age, :name ])
       contact = Contact.new.send("from_#{format}", @serialized)
       assert_equal @contact_attributes[:name], contact.name, "For #{format}"
       assert_nil contact.avatar, "For #{format}"
@@ -47,7 +49,7 @@ class SerializationTest < ActiveRecord::TestCase
 
   def test_serialize_should_allow_attribute_except_filtering
     FORMATS.each do |format|
-      @serialized = Contact.new(@contact_attributes).send("to_#{format}", :except => [ :age, :name ])
+      @serialized = Contact.new(@contact_attributes).send("to_#{format}", except: [ :age, :name ])
       contact = Contact.new.send("from_#{format}", @serialized)
       assert_nil contact.name, "For #{format}"
       assert_nil contact.age, "For #{format}"
@@ -60,7 +62,7 @@ class SerializationTest < ActiveRecord::TestCase
     ActiveRecord::Base.include_root_in_json = true
 
     klazz = Class.new(ActiveRecord::Base)
-    klazz.table_name = 'topics'
+    klazz.table_name = "topics"
     assert klazz.include_root_in_json
 
     klazz.include_root_in_json = false
@@ -73,7 +75,7 @@ class SerializationTest < ActiveRecord::TestCase
 
   def test_read_attribute_for_serialization_with_format_without_method_missing
     klazz = Class.new(ActiveRecord::Base)
-    klazz.table_name = 'books'
+    klazz.table_name = "books"
 
     book = klazz.new
     assert_nil book.read_attribute_for_serialization(:format)
@@ -81,18 +83,18 @@ class SerializationTest < ActiveRecord::TestCase
 
   def test_read_attribute_for_serialization_with_format_after_init
     klazz = Class.new(ActiveRecord::Base)
-    klazz.table_name = 'books'
+    klazz.table_name = "books"
 
-    book = klazz.new(format: 'paperback')
-    assert_equal 'paperback', book.read_attribute_for_serialization(:format)
+    book = klazz.new(format: "paperback")
+    assert_equal "paperback", book.read_attribute_for_serialization(:format)
   end
 
   def test_read_attribute_for_serialization_with_format_after_find
     klazz = Class.new(ActiveRecord::Base)
-    klazz.table_name = 'books'
+    klazz.table_name = "books"
 
     book = klazz.find(books(:awdr).id)
-    assert_equal 'paperback', book.read_attribute_for_serialization(:format)
+    assert_equal "paperback", book.read_attribute_for_serialization(:format)
   end
 
   def test_find_records_by_serialized_attributes_through_join
diff --git a/activerecord/test/cases/serialized_attribute_test.rb b/activerecord/test/cases/serialized_attribute_test.rb
index 846be857d0..32dafbd458 100644
--- a/activerecord/test/cases/serialized_attribute_test.rb
+++ b/activerecord/test/cases/serialized_attribute_test.rb
@@ -1,10 +1,12 @@
-require 'cases/helper'
-require 'models/topic'
-require 'models/reply'
-require 'models/person'
-require 'models/traffic_light'
-require 'models/post'
-require 'bcrypt'
+# frozen_string_literal: true
+
+require "cases/helper"
+require "models/topic"
+require "models/reply"
+require "models/person"
+require "models/traffic_light"
+require "models/post"
+require "bcrypt"
 
 class SerializedAttributeTest < ActiveRecord::TestCase
   fixtures :topics, :posts
@@ -25,7 +27,7 @@ class SerializedAttributeTest < ActiveRecord::TestCase
   def test_serialized_attribute
     Topic.serialize("content", MyObject)
 
-    myobj = MyObject.new('value1', 'value2')
+    myobj = MyObject.new("value1", "value2")
     topic = Topic.create("content" => myobj)
     assert_equal(myobj, topic.content)
 
@@ -36,7 +38,7 @@ class SerializedAttributeTest < ActiveRecord::TestCase
   def test_serialized_attribute_in_base_class
     Topic.serialize("content", Hash)
 
-    hash = { 'content1' => 'value1', 'content2' => 'value2' }
+    hash = { "content1" => "value1", "content2" => "value2" }
     important_topic = ImportantTopic.create("content" => hash)
     assert_equal(hash, important_topic.content)
 
@@ -97,7 +99,7 @@ class SerializedAttributeTest < ActiveRecord::TestCase
   end
 
   def test_serialized_attribute_declared_in_subclass
-    hash = { 'important1' => 'value1', 'important2' => 'value2' }
+    hash = { "important1" => "value1", "important2" => "value2" }
     important_topic = ImportantTopic.create("important" => hash)
     assert_equal(hash, important_topic.important)
 
@@ -107,7 +109,7 @@ class SerializedAttributeTest < ActiveRecord::TestCase
   end
 
   def test_serialized_time_attribute
-    myobj = Time.local(2008,1,1,1,0)
+    myobj = Time.local(2008, 1, 1, 1, 0)
     topic = Topic.create("content" => myobj).reload
     assert_equal(myobj, topic.content)
   end
@@ -124,26 +126,26 @@ class SerializedAttributeTest < ActiveRecord::TestCase
   end
 
   def test_nil_not_serialized_without_class_constraint
-    assert Topic.new(:content => nil).save
-    assert_equal 1, Topic.where(:content => nil).count
+    assert Topic.new(content: nil).save
+    assert_equal 1, Topic.where(content: nil).count
   end
 
   def test_nil_not_serialized_with_class_constraint
     Topic.serialize :content, Hash
-    assert Topic.new(:content => nil).save
-    assert_equal 1, Topic.where(:content => nil).count
+    assert Topic.new(content: nil).save
+    assert_equal 1, Topic.where(content: nil).count
   end
 
   def test_serialized_attribute_should_raise_exception_on_assignment_with_wrong_type
     Topic.serialize(:content, Hash)
     assert_raise(ActiveRecord::SerializationTypeMismatch) do
-      Topic.new(content: 'string')
+      Topic.new(content: "string")
     end
   end
 
   def test_should_raise_exception_on_serialized_attribute_with_type_mismatch
-    myobj = MyObject.new('value1', 'value2')
-    topic = Topic.new(:content => myobj)
+    myobj = MyObject.new("value1", "value2")
+    topic = Topic.new(content: myobj)
     assert topic.save
     Topic.serialize(:content, Hash)
     assert_raise(ActiveRecord::SerializationTypeMismatch) { Topic.find(topic.id).content }
@@ -152,11 +154,18 @@ class SerializedAttributeTest < ActiveRecord::TestCase
   def test_serialized_attribute_with_class_constraint
     settings = { "color" => "blue" }
     Topic.serialize(:content, Hash)
-    topic = Topic.new(:content => settings)
+    topic = Topic.new(content: settings)
     assert topic.save
     assert_equal(settings, Topic.find(topic.id).content)
   end
 
+  def test_where_by_serialized_attribute_with_hash
+    settings = { "color" => "green" }
+    Topic.serialize(:content, Hash)
+    topic = Topic.create!(content: settings)
+    assert_equal topic, Topic.where(content: settings).take
+  end
+
   def test_serialized_default_class
     Topic.serialize(:content, Hash)
     topic = Topic.new
@@ -175,17 +184,17 @@ class SerializedAttributeTest < ActiveRecord::TestCase
   end
 
   def test_serialized_boolean_value_true
-    topic = Topic.new(:content => true)
+    topic = Topic.new(content: true)
     assert topic.save
     topic = topic.reload
-    assert_equal topic.content, true
+    assert_equal true, topic.content
   end
 
   def test_serialized_boolean_value_false
-    topic = Topic.new(:content => false)
+    topic = Topic.new(content: false)
     assert topic.save
     topic = topic.reload
-    assert_equal topic.content, false
+    assert_equal false, topic.content
   end
 
   def test_serialize_with_coder
@@ -200,18 +209,18 @@ class SerializedAttributeTest < ActiveRecord::TestCase
     end
 
     Topic.serialize(:content, some_class)
-    topic = Topic.new(:content => some_class.new('my value'))
+    topic = Topic.new(content: some_class.new("my value"))
     topic.save!
     topic.reload
     assert_kind_of some_class, topic.content
-    assert_equal topic.content, some_class.new('my value')
+    assert_equal some_class.new("my value"), topic.content
   end
 
   def test_serialize_attribute_via_select_method_when_time_zone_available
     with_timezone_config aware_attributes: true do
       Topic.serialize(:content, MyObject)
 
-      myobj = MyObject.new('value1', 'value2')
+      myobj = MyObject.new("value1", "value2")
       topic = Topic.create(content: myobj)
 
       assert_equal(myobj, Topic.select(:content).find(topic.id).content)
@@ -220,8 +229,8 @@ class SerializedAttributeTest < ActiveRecord::TestCase
   end
 
   def test_serialize_attribute_can_be_serialized_in_an_integer_column
-    insures = ['life']
-    person = SerializedPerson.new(first_name: 'David', insures: insures)
+    insures = ["life"]
+    person = SerializedPerson.new(first_name: "David", insures: insures)
     assert person.save
     person = person.reload
     assert_equal(insures, person.insures)
@@ -233,6 +242,20 @@ class SerializedAttributeTest < ActiveRecord::TestCase
     assert_equal [], light.long_state
   end
 
+  def test_unexpected_serialized_type
+    Topic.serialize :content, Hash
+    topic = Topic.create!(content: { zomg: true })
+
+    Topic.serialize :content, Array
+
+    topic.reload
+    error = assert_raise(ActiveRecord::SerializationTypeMismatch) do
+      topic.content
+    end
+    expected = "can't load `content`: was supposed to be a Array, but was a Hash. -- {:zomg=>true}"
+    assert_equal expected, error.to_s
+  end
+
   def test_serialized_column_should_unserialize_after_update_column
     t = Topic.create(content: "first")
     assert_equal("first", t.content)
@@ -328,4 +351,32 @@ class SerializedAttributeTest < ActiveRecord::TestCase
     topic.foo
     refute topic.changed?
   end
+
+  def test_serialized_attribute_works_under_concurrent_initial_access
+    model = Topic.dup
+
+    topic = model.last
+    topic.update group: "1"
+
+    model.serialize :group, JSON
+    model.reset_column_information
+
+    # This isn't strictly necessary for the test, but a little bit of
+    # knowledge of internals allows us to make failures far more likely.
+    model.define_singleton_method(:define_attribute) do |*args|
+      Thread.pass
+      super(*args)
+    end
+
+    threads = 4.times.map do
+      Thread.new do
+        topic.reload.group
+      end
+    end
+
+    # All the threads should retrieve the value knowing it is JSON, and
+    # thus decode it. If this fails, some threads will instead see the
+    # raw string ("1"), or raise an exception.
+    assert_equal [1] * threads.size, threads.map(&:value)
+  end
 end
diff --git a/activerecord/test/cases/statement_cache_test.rb b/activerecord/test/cases/statement_cache_test.rb
index 104226010a..ad6cd198e2 100644
--- a/activerecord/test/cases/statement_cache_test.rb
+++ b/activerecord/test/cases/statement_cache_test.rb
@@ -1,8 +1,10 @@
-require 'cases/helper'
-require 'models/book'
-require 'models/liquid'
-require 'models/molecule'
-require 'models/electron'
+# frozen_string_literal: true
+
+require "cases/helper"
+require "models/book"
+require "models/liquid"
+require "models/molecule"
+require "models/electron"
 
 module ActiveRecord
   class StatementCacheTest < ActiveRecord::TestCase
@@ -10,22 +12,20 @@ module ActiveRecord
       @connection = ActiveRecord::Base.connection
     end
 
-    #Cache v 1.1 tests
     def test_statement_cache
       Book.create(name: "my book")
       Book.create(name: "my other book")
 
       cache = StatementCache.create(Book.connection) do |params|
-        Book.where(:name => params.bind)
+        Book.where(name: params.bind)
       end
 
-      b = cache.execute([ "my book" ], Book, Book.connection)
+      b = cache.execute([ "my book" ], Book.connection)
       assert_equal "my book", b[0].name
-      b = cache.execute([ "my other book" ], Book, Book.connection)
+      b = cache.execute([ "my other book" ], Book.connection)
       assert_equal "my other book", b[0].name
     end
 
-
     def test_statement_cache_id
       b1 = Book.create(name: "my book")
       b2 = Book.create(name: "my other book")
@@ -34,9 +34,9 @@ module ActiveRecord
         Book.where(id: params.bind)
       end
 
-      b = cache.execute([ b1.id ], Book, Book.connection)
+      b = cache.execute([ b1.id ], Book.connection)
       assert_equal b1.name, b[0].name
-      b = cache.execute([ b2.id ], Book, Book.connection)
+      b = cache.execute([ b2.id ], Book.connection)
       assert_equal b2.name, b[0].name
     end
 
@@ -50,8 +50,6 @@ module ActiveRecord
       assert_equal("my other book", b.name)
     end
 
-    #End
-
     def test_statement_cache_with_simple_statement
       cache = ActiveRecord::StatementCache.create(Book.connection) do |params|
         Book.where(name: "my book").where("author_id > 3")
@@ -59,20 +57,20 @@ module ActiveRecord
 
       Book.create(name: "my book", author_id: 4)
 
-      books = cache.execute([], Book, Book.connection)
+      books = cache.execute([], Book.connection)
       assert_equal "my book", books[0].name
     end
 
     def test_statement_cache_with_complex_statement
       cache = ActiveRecord::StatementCache.create(Book.connection) do |params|
-        Liquid.joins(:molecules => :electrons).where('molecules.name' => 'dioxane', 'electrons.name' => 'lepton')
+        Liquid.joins(molecules: :electrons).where("molecules.name" => "dioxane", "electrons.name" => "lepton")
       end
 
-      salty = Liquid.create(name: 'salty')
-      molecule = salty.molecules.create(name: 'dioxane')
-      molecule.electrons.create(name: 'lepton')
+      salty = Liquid.create(name: "salty")
+      molecule = salty.molecules.create(name: "dioxane")
+      molecule.electrons.create(name: "lepton")
 
-      liquids = cache.execute([], Book, Book.connection)
+      liquids = cache.execute([], Book.connection)
       assert_equal "salty", liquids[0].name
     end
 
@@ -85,13 +83,13 @@ module ActiveRecord
         Book.create(name: "my book")
       end
 
-      first_books = cache.execute([], Book, Book.connection)
+      first_books = cache.execute([], Book.connection)
 
       3.times do
         Book.create(name: "my book")
       end
 
-      additional_books = cache.execute([], Book, Book.connection)
+      additional_books = cache.execute([], Book.connection)
       assert first_books != additional_books
     end
 
@@ -106,5 +104,31 @@ module ActiveRecord
 
       refute_equal book, other_book
     end
+
+    def test_find_by_does_not_use_statement_cache_if_table_name_is_changed
+      book = Book.create(name: "my book")
+
+      Book.find_by(name: book.name) # warming the statement cache.
+
+      # changing the table name should change the query that is not cached.
+      Book.table_name = :birds
+      assert_nil Book.find_by(name: book.name)
+    ensure
+      Book.table_name = :books
+    end
+
+    def test_find_does_not_use_statement_cache_if_table_name_is_changed
+      book = Book.create(name: "my book")
+
+      Book.find(book.id) # warming the statement cache.
+
+      # changing the table name should change the query that is not cached.
+      Book.table_name = :birds
+      assert_raise ActiveRecord::RecordNotFound do
+        Book.find(book.id)
+      end
+    ensure
+      Book.table_name = :books
+    end
   end
 end
diff --git a/activerecord/test/cases/store_test.rb b/activerecord/test/cases/store_test.rb
index bce86875e1..ebf4016960 100644
--- a/activerecord/test/cases/store_test.rb
+++ b/activerecord/test/cases/store_test.rb
@@ -1,55 +1,57 @@
-require 'cases/helper'
-require 'models/admin'
-require 'models/admin/user'
+# frozen_string_literal: true
+
+require "cases/helper"
+require "models/admin"
+require "models/admin/user"
 
 class StoreTest < ActiveRecord::TestCase
   fixtures :'admin/users'
 
   setup do
-    @john = Admin::User.create!(:name => 'John Doe', :color => 'black', :remember_login => true, :height => 'tall', :is_a_good_guy => true)
+    @john = Admin::User.create!(name: "John Doe", color: "black", remember_login: true, height: "tall", is_a_good_guy: true)
   end
 
   test "reading store attributes through accessors" do
-    assert_equal 'black', @john.color
+    assert_equal "black", @john.color
     assert_nil @john.homepage
   end
 
   test "writing store attributes through accessors" do
-    @john.color = 'red'
-    @john.homepage = '37signals.com'
+    @john.color = "red"
+    @john.homepage = "37signals.com"
 
-    assert_equal 'red', @john.color
-    assert_equal '37signals.com', @john.homepage
+    assert_equal "red", @john.color
+    assert_equal "37signals.com", @john.homepage
   end
 
   test "accessing attributes not exposed by accessors" do
-    @john.settings[:icecream] = 'graeters'
+    @john.settings[:icecream] = "graeters"
     @john.save
 
-    assert_equal 'graeters', @john.reload.settings[:icecream]
+    assert_equal "graeters", @john.reload.settings[:icecream]
   end
 
   test "overriding a read accessor" do
-    @john.settings[:phone_number] = '1234567890'
+    @john.settings[:phone_number] = "1234567890"
 
-    assert_equal '(123) 456-7890', @john.phone_number
+    assert_equal "(123) 456-7890", @john.phone_number
   end
 
   test "overriding a read accessor using super" do
     @john.settings[:color] = nil
 
-    assert_equal 'red', @john.color
+    assert_equal "red", @john.color
   end
 
   test "updating the store will mark it as changed" do
-    @john.color = 'red'
+    @john.color = "red"
     assert @john.settings_changed?
   end
 
   test "updating the store populates the changed array correctly" do
-    @john.color = 'red'
-    assert_equal 'black', @john.settings_change[0]['color']
-    assert_equal 'red', @john.settings_change[1]['color']
+    @john.color = "red"
+    assert_equal "black", @john.settings_change[0]["color"]
+    assert_equal "red", @john.settings_change[1]["color"]
   end
 
   test "updating the store won't mark it as changed if an attribute isn't changed" do
@@ -67,74 +69,74 @@ class StoreTest < ActiveRecord::TestCase
   end
 
   test "overriding a write accessor" do
-    @john.phone_number = '(123) 456-7890'
+    @john.phone_number = "(123) 456-7890"
 
-    assert_equal '1234567890', @john.settings[:phone_number]
+    assert_equal "1234567890", @john.settings[:phone_number]
   end
 
   test "overriding a write accessor using super" do
-    @john.color = 'yellow'
+    @john.color = "yellow"
 
-    assert_equal 'blue', @john.color
+    assert_equal "blue", @john.color
   end
 
   test "preserve store attributes data in HashWithIndifferentAccess format without any conversion" do
-    @john.json_data = ActiveSupport::HashWithIndifferentAccess.new(:height => 'tall', 'weight' => 'heavy')
-    @john.height = 'low'
+    @john.json_data = ActiveSupport::HashWithIndifferentAccess.new(:height => "tall", "weight" => "heavy")
+    @john.height = "low"
     assert_equal true, @john.json_data.instance_of?(ActiveSupport::HashWithIndifferentAccess)
-    assert_equal 'low', @john.json_data[:height]
-    assert_equal 'low', @john.json_data['height']
-    assert_equal 'heavy', @john.json_data[:weight]
-    assert_equal 'heavy', @john.json_data['weight']
+    assert_equal "low", @john.json_data[:height]
+    assert_equal "low", @john.json_data["height"]
+    assert_equal "heavy", @john.json_data[:weight]
+    assert_equal "heavy", @john.json_data["weight"]
   end
 
   test "convert store attributes from Hash to HashWithIndifferentAccess saving the data and access attributes indifferently" do
-    user = Admin::User.find_by_name('Jamis')
-    assert_equal 'symbol',  user.settings[:symbol]
-    assert_equal 'symbol',  user.settings['symbol']
-    assert_equal 'string',  user.settings[:string]
-    assert_equal 'string',  user.settings['string']
+    user = Admin::User.find_by_name("Jamis")
+    assert_equal "symbol",  user.settings[:symbol]
+    assert_equal "symbol",  user.settings["symbol"]
+    assert_equal "string",  user.settings[:string]
+    assert_equal "string",  user.settings["string"]
     assert_equal true,      user.settings.instance_of?(ActiveSupport::HashWithIndifferentAccess)
 
-    user.height = 'low'
-    assert_equal 'symbol',  user.settings[:symbol]
-    assert_equal 'symbol',  user.settings['symbol']
-    assert_equal 'string',  user.settings[:string]
-    assert_equal 'string',  user.settings['string']
+    user.height = "low"
+    assert_equal "symbol",  user.settings[:symbol]
+    assert_equal "symbol",  user.settings["symbol"]
+    assert_equal "string",  user.settings[:string]
+    assert_equal "string",  user.settings["string"]
     assert_equal true,      user.settings.instance_of?(ActiveSupport::HashWithIndifferentAccess)
   end
 
   test "convert store attributes from any format other than Hash or HashWithIndifferentAccess losing the data" do
     @john.json_data = "somedata"
-    @john.height = 'low'
+    @john.height = "low"
     assert_equal true, @john.json_data.instance_of?(ActiveSupport::HashWithIndifferentAccess)
-    assert_equal 'low', @john.json_data[:height]
-    assert_equal 'low', @john.json_data['height']
-    assert_equal false, @john.json_data.delete_if { |k, v| k == 'height' }.any?
+    assert_equal "low", @john.json_data[:height]
+    assert_equal "low", @john.json_data["height"]
+    assert_equal false, @john.json_data.delete_if { |k, v| k == "height" }.any?
   end
 
   test "reading store attributes through accessors encoded with JSON" do
-    assert_equal 'tall', @john.height
+    assert_equal "tall", @john.height
     assert_nil @john.weight
   end
 
   test "writing store attributes through accessors encoded with JSON" do
-    @john.height = 'short'
-    @john.weight = 'heavy'
+    @john.height = "short"
+    @john.weight = "heavy"
 
-    assert_equal 'short', @john.height
-    assert_equal 'heavy', @john.weight
+    assert_equal "short", @john.height
+    assert_equal "heavy", @john.weight
   end
 
   test "accessing attributes not exposed by accessors encoded with JSON" do
-    @john.json_data['somestuff'] = 'somecoolstuff'
+    @john.json_data["somestuff"] = "somecoolstuff"
     @john.save
 
-    assert_equal 'somecoolstuff', @john.reload.json_data['somestuff']
+    assert_equal "somecoolstuff", @john.reload.json_data["somestuff"]
   end
 
   test "updating the store will mark it as changed encoded with JSON" do
-    @john.height = 'short'
+    @john.height = "short"
     assert @john.json_data_changed?
   end
 
diff --git a/activerecord/test/cases/suppressor_test.rb b/activerecord/test/cases/suppressor_test.rb
index 2f00241de2..b68f0033d9 100644
--- a/activerecord/test/cases/suppressor_test.rb
+++ b/activerecord/test/cases/suppressor_test.rb
@@ -1,6 +1,8 @@
-require 'cases/helper'
-require 'models/notification'
-require 'models/user'
+# frozen_string_literal: true
+
+require "cases/helper"
+require "models/notification"
+require "models/user"
 
 class SuppressorTest < ActiveRecord::TestCase
   def test_suppresses_create
@@ -15,22 +17,22 @@ class SuppressorTest < ActiveRecord::TestCase
   end
 
   def test_suppresses_update
-    user = User.create! token: 'asdf'
+    user = User.create! token: "asdf"
 
     User.suppress do
-      user.update token: 'ghjkl'
-      assert_equal 'asdf', user.reload.token
+      user.update token: "ghjkl"
+      assert_equal "asdf", user.reload.token
 
-      user.update! token: 'zxcvbnm'
-      assert_equal 'asdf', user.reload.token
+      user.update! token: "zxcvbnm"
+      assert_equal "asdf", user.reload.token
 
-      user.token = 'qwerty'
+      user.token = "qwerty"
       user.save
-      assert_equal 'asdf', user.reload.token
+      assert_equal "asdf", user.reload.token
 
-      user.token = 'uiop'
+      user.token = "uiop"
       user.save!
-      assert_equal 'asdf', user.reload.token
+      assert_equal "asdf", user.reload.token
     end
   end
 
@@ -64,7 +66,7 @@ class SuppressorTest < ActiveRecord::TestCase
   def test_suppresses_when_nested_multiple_times
     assert_no_difference -> { Notification.count } do
       Notification.suppress do
-        Notification.suppress { }
+        Notification.suppress {}
         Notification.create
         Notification.create!
         Notification.new.save
diff --git a/activerecord/test/cases/tasks/database_tasks_test.rb b/activerecord/test/cases/tasks/database_tasks_test.rb
index 510bb088c8..c114842dec 100644
--- a/activerecord/test/cases/tasks/database_tasks_test.rb
+++ b/activerecord/test/cases/tasks/database_tasks_test.rb
@@ -1,5 +1,7 @@
-require 'cases/helper'
-require 'active_record/tasks/database_tasks'
+# frozen_string_literal: true
+
+require "cases/helper"
+require "active_record/tasks/database_tasks"
 
 module ActiveRecord
   module DatabaseTasksSetupper
@@ -24,17 +26,34 @@ module ActiveRecord
     sqlite3:    :sqlite_tasks
   }
 
-  class DatabaseTasksUtilsTask< ActiveRecord::TestCase
+  class DatabaseTasksUtilsTask < ActiveRecord::TestCase
     def test_raises_an_error_when_called_with_protected_environment
       ActiveRecord::Migrator.stubs(:current_version).returns(1)
 
-      protected_environments = ActiveRecord::Base.protected_environments.dup
+      protected_environments = ActiveRecord::Base.protected_environments
       current_env            = ActiveRecord::Migrator.current_environment
-      assert !protected_environments.include?(current_env)
+      assert_not_includes protected_environments, current_env
       # Assert no error
       ActiveRecord::Tasks::DatabaseTasks.check_protected_environments!
 
-      ActiveRecord::Base.protected_environments << current_env
+      ActiveRecord::Base.protected_environments = [current_env]
+      assert_raise(ActiveRecord::ProtectedEnvironmentError) do
+        ActiveRecord::Tasks::DatabaseTasks.check_protected_environments!
+      end
+    ensure
+      ActiveRecord::Base.protected_environments = protected_environments
+    end
+
+    def test_raises_an_error_when_called_with_protected_environment_which_name_is_a_symbol
+      ActiveRecord::Migrator.stubs(:current_version).returns(1)
+
+      protected_environments = ActiveRecord::Base.protected_environments
+      current_env            = ActiveRecord::Migrator.current_environment
+      assert_not_includes protected_environments, current_env
+      # Assert no error
+      ActiveRecord::Tasks::DatabaseTasks.check_protected_environments!
+
+      ActiveRecord::Base.protected_environments = [current_env.to_sym]
       assert_raise(ActiveRecord::ProtectedEnvironmentError) do
         ActiveRecord::Tasks::DatabaseTasks.check_protected_environments!
       end
@@ -61,15 +80,15 @@ module ActiveRecord
       instance = klazz.new
 
       klazz.stubs(:new).returns instance
-      instance.expects(:structure_dump).with("awesome-file.sql")
+      instance.expects(:structure_dump).with("awesome-file.sql", nil)
 
       ActiveRecord::Tasks::DatabaseTasks.register_task(/foo/, klazz)
-      ActiveRecord::Tasks::DatabaseTasks.structure_dump({'adapter' => :foo}, "awesome-file.sql")
+      ActiveRecord::Tasks::DatabaseTasks.structure_dump({ "adapter" => :foo }, "awesome-file.sql")
     end
 
     def test_unregistered_task
       assert_raise(ActiveRecord::Tasks::DatabaseNotSupported) do
-        ActiveRecord::Tasks::DatabaseTasks.structure_dump({'adapter' => :bar}, "awesome-file.sql")
+        ActiveRecord::Tasks::DatabaseTasks.structure_dump({ "adapter" => :bar }, "awesome-file.sql")
       end
     end
   end
@@ -80,20 +99,33 @@ module ActiveRecord
     ADAPTERS_TASKS.each do |k, v|
       define_method("test_#{k}_create") do
         eval("@#{v}").expects(:create)
-        ActiveRecord::Tasks::DatabaseTasks.create 'adapter' => k
+        ActiveRecord::Tasks::DatabaseTasks.create "adapter" => k
       end
     end
   end
 
+  class DatabaseTasksDumpSchemaCacheTest < ActiveRecord::TestCase
+    def test_dump_schema_cache
+      path = "/tmp/my_schema_cache.yml"
+      ActiveRecord::Tasks::DatabaseTasks.dump_schema_cache(ActiveRecord::Base.connection, path)
+      assert File.file?(path)
+    ensure
+      ActiveRecord::Base.clear_cache!
+      FileUtils.rm_rf(path)
+    end
+  end
+
   class DatabaseTasksCreateAllTest < ActiveRecord::TestCase
     def setup
-      @configurations = {'development' => {'database' => 'my-db'}}
+      @configurations = { "development" => { "database" => "my-db" } }
 
       ActiveRecord::Base.stubs(:configurations).returns(@configurations)
+      # To refrain from connecting to a newly created empty DB in sqlite3_mem tests
+      ActiveRecord::Base.connection_handler.stubs(:establish_connection)
     end
 
     def test_ignores_configurations_without_databases
-      @configurations['development'].merge!('database' => nil)
+      @configurations["development"].merge!("database" => nil)
 
       ActiveRecord::Tasks::DatabaseTasks.expects(:create).never
 
@@ -101,7 +133,7 @@ module ActiveRecord
     end
 
     def test_ignores_remote_databases
-      @configurations['development'].merge!('host' => 'my.server.tld')
+      @configurations["development"].merge!("host" => "my.server.tld")
       $stderr.stubs(:puts).returns(nil)
 
       ActiveRecord::Tasks::DatabaseTasks.expects(:create).never
@@ -110,15 +142,15 @@ module ActiveRecord
     end
 
     def test_warning_for_remote_databases
-      @configurations['development'].merge!('host' => 'my.server.tld')
+      @configurations["development"].merge!("host" => "my.server.tld")
 
-      $stderr.expects(:puts).with('This task only modifies local databases. my-db is on a remote host.')
+      $stderr.expects(:puts).with("This task only modifies local databases. my-db is on a remote host.")
 
       ActiveRecord::Tasks::DatabaseTasks.create_all
     end
 
     def test_creates_configurations_with_local_ip
-      @configurations['development'].merge!('host' => '127.0.0.1')
+      @configurations["development"].merge!("host" => "127.0.0.1")
 
       ActiveRecord::Tasks::DatabaseTasks.expects(:create)
 
@@ -126,7 +158,7 @@ module ActiveRecord
     end
 
     def test_creates_configurations_with_local_host
-      @configurations['development'].merge!('host' => 'localhost')
+      @configurations["development"].merge!("host" => "localhost")
 
       ActiveRecord::Tasks::DatabaseTasks.expects(:create)
 
@@ -134,7 +166,7 @@ module ActiveRecord
     end
 
     def test_creates_configurations_with_blank_hosts
-      @configurations['development'].merge!('host' => nil)
+      @configurations["development"].merge!("host" => nil)
 
       ActiveRecord::Tasks::DatabaseTasks.expects(:create)
 
@@ -145,9 +177,9 @@ module ActiveRecord
   class DatabaseTasksCreateCurrentTest < ActiveRecord::TestCase
     def setup
       @configurations = {
-        'development' => {'database' => 'dev-db'},
-        'test'        => {'database' => 'test-db'},
-        'production'  => {'database' => 'prod-db'}
+        "development" => { "database" => "dev-db" },
+        "test"        => { "database" => "test-db" },
+        "production"  => { "database" => "prod-db" }
       }
 
       ActiveRecord::Base.stubs(:configurations).returns(@configurations)
@@ -156,37 +188,37 @@ module ActiveRecord
 
     def test_creates_current_environment_database
       ActiveRecord::Tasks::DatabaseTasks.expects(:create).
-        with('database' => 'prod-db')
+        with("database" => "prod-db")
 
       ActiveRecord::Tasks::DatabaseTasks.create_current(
-        ActiveSupport::StringInquirer.new('production')
+        ActiveSupport::StringInquirer.new("production")
       )
     end
 
     def test_creates_test_and_development_databases_when_env_was_not_specified
       ActiveRecord::Tasks::DatabaseTasks.expects(:create).
-        with('database' => 'dev-db')
+        with("database" => "dev-db")
       ActiveRecord::Tasks::DatabaseTasks.expects(:create).
-        with('database' => 'test-db')
+        with("database" => "test-db")
 
       ActiveRecord::Tasks::DatabaseTasks.create_current(
-        ActiveSupport::StringInquirer.new('development')
+        ActiveSupport::StringInquirer.new("development")
       )
     end
 
     def test_creates_test_and_development_databases_when_rails_env_is_development
-      old_env = ENV['RAILS_ENV']
-      ENV['RAILS_ENV'] = 'development'
+      old_env = ENV["RAILS_ENV"]
+      ENV["RAILS_ENV"] = "development"
       ActiveRecord::Tasks::DatabaseTasks.expects(:create).
-        with('database' => 'dev-db')
+        with("database" => "dev-db")
       ActiveRecord::Tasks::DatabaseTasks.expects(:create).
-        with('database' => 'test-db')
+        with("database" => "test-db")
 
       ActiveRecord::Tasks::DatabaseTasks.create_current(
-        ActiveSupport::StringInquirer.new('development')
+        ActiveSupport::StringInquirer.new("development")
       )
     ensure
-      ENV['RAILS_ENV'] = old_env
+      ENV["RAILS_ENV"] = old_env
     end
 
     def test_establishes_connection_for_the_given_environment
@@ -195,7 +227,7 @@ module ActiveRecord
       ActiveRecord::Base.expects(:establish_connection).with(:development)
 
       ActiveRecord::Tasks::DatabaseTasks.create_current(
-        ActiveSupport::StringInquirer.new('development')
+        ActiveSupport::StringInquirer.new("development")
       )
     end
   end
@@ -206,20 +238,20 @@ module ActiveRecord
     ADAPTERS_TASKS.each do |k, v|
       define_method("test_#{k}_drop") do
         eval("@#{v}").expects(:drop)
-        ActiveRecord::Tasks::DatabaseTasks.drop 'adapter' => k
+        ActiveRecord::Tasks::DatabaseTasks.drop "adapter" => k
       end
     end
   end
 
   class DatabaseTasksDropAllTest < ActiveRecord::TestCase
     def setup
-      @configurations = {:development => {'database' => 'my-db'}}
+      @configurations = { development: { "database" => "my-db" } }
 
       ActiveRecord::Base.stubs(:configurations).returns(@configurations)
     end
 
     def test_ignores_configurations_without_databases
-      @configurations[:development].merge!('database' => nil)
+      @configurations[:development].merge!("database" => nil)
 
       ActiveRecord::Tasks::DatabaseTasks.expects(:drop).never
 
@@ -227,7 +259,7 @@ module ActiveRecord
     end
 
     def test_ignores_remote_databases
-      @configurations[:development].merge!('host' => 'my.server.tld')
+      @configurations[:development].merge!("host" => "my.server.tld")
       $stderr.stubs(:puts).returns(nil)
 
       ActiveRecord::Tasks::DatabaseTasks.expects(:drop).never
@@ -236,15 +268,15 @@ module ActiveRecord
     end
 
     def test_warning_for_remote_databases
-      @configurations[:development].merge!('host' => 'my.server.tld')
+      @configurations[:development].merge!("host" => "my.server.tld")
 
-      $stderr.expects(:puts).with('This task only modifies local databases. my-db is on a remote host.')
+      $stderr.expects(:puts).with("This task only modifies local databases. my-db is on a remote host.")
 
       ActiveRecord::Tasks::DatabaseTasks.drop_all
     end
 
     def test_drops_configurations_with_local_ip
-      @configurations[:development].merge!('host' => '127.0.0.1')
+      @configurations[:development].merge!("host" => "127.0.0.1")
 
       ActiveRecord::Tasks::DatabaseTasks.expects(:drop)
 
@@ -252,7 +284,7 @@ module ActiveRecord
     end
 
     def test_drops_configurations_with_local_host
-      @configurations[:development].merge!('host' => 'localhost')
+      @configurations[:development].merge!("host" => "localhost")
 
       ActiveRecord::Tasks::DatabaseTasks.expects(:drop)
 
@@ -260,7 +292,7 @@ module ActiveRecord
     end
 
     def test_drops_configurations_with_blank_hosts
-      @configurations[:development].merge!('host' => nil)
+      @configurations[:development].merge!("host" => nil)
 
       ActiveRecord::Tasks::DatabaseTasks.expects(:drop)
 
@@ -271,9 +303,9 @@ module ActiveRecord
   class DatabaseTasksDropCurrentTest < ActiveRecord::TestCase
     def setup
       @configurations = {
-        'development' => {'database' => 'dev-db'},
-        'test'        => {'database' => 'test-db'},
-        'production'  => {'database' => 'prod-db'}
+        "development" => { "database" => "dev-db" },
+        "test"        => { "database" => "test-db" },
+        "production"  => { "database" => "prod-db" }
       }
 
       ActiveRecord::Base.stubs(:configurations).returns(@configurations)
@@ -281,37 +313,37 @@ module ActiveRecord
 
     def test_drops_current_environment_database
       ActiveRecord::Tasks::DatabaseTasks.expects(:drop).
-        with('database' => 'prod-db')
+        with("database" => "prod-db")
 
       ActiveRecord::Tasks::DatabaseTasks.drop_current(
-        ActiveSupport::StringInquirer.new('production')
+        ActiveSupport::StringInquirer.new("production")
       )
     end
 
     def test_drops_test_and_development_databases_when_env_was_not_specified
       ActiveRecord::Tasks::DatabaseTasks.expects(:drop).
-        with('database' => 'dev-db')
+        with("database" => "dev-db")
       ActiveRecord::Tasks::DatabaseTasks.expects(:drop).
-        with('database' => 'test-db')
+        with("database" => "test-db")
 
       ActiveRecord::Tasks::DatabaseTasks.drop_current(
-        ActiveSupport::StringInquirer.new('development')
+        ActiveSupport::StringInquirer.new("development")
       )
     end
 
     def test_drops_testand_development_databases_when_rails_env_is_development
-      old_env = ENV['RAILS_ENV']
-      ENV['RAILS_ENV'] = 'development'
+      old_env = ENV["RAILS_ENV"]
+      ENV["RAILS_ENV"] = "development"
       ActiveRecord::Tasks::DatabaseTasks.expects(:drop).
-        with('database' => 'dev-db')
+        with("database" => "dev-db")
       ActiveRecord::Tasks::DatabaseTasks.expects(:drop).
-        with('database' => 'test-db')
+        with("database" => "test-db")
 
       ActiveRecord::Tasks::DatabaseTasks.drop_current(
-        ActiveSupport::StringInquirer.new('development')
+        ActiveSupport::StringInquirer.new("development")
       )
     ensure
-      ENV['RAILS_ENV'] = old_env
+      ENV["RAILS_ENV"] = old_env
     end
   end
 
@@ -319,7 +351,7 @@ module ActiveRecord
     self.use_transactional_tests = false
 
     def setup
-      ActiveRecord::Tasks::DatabaseTasks.migrations_paths = 'custom/path'
+      ActiveRecord::Tasks::DatabaseTasks.migrations_paths = "custom/path"
     end
 
     def teardown
@@ -327,15 +359,78 @@ module ActiveRecord
     end
 
     def test_migrate_receives_correct_env_vars
-      verbose, version = ENV['VERBOSE'], ENV['VERSION']
+      verbose, version = ENV["VERBOSE"], ENV["VERSION"]
 
-      ENV['VERBOSE'] = 'false'
-      ENV['VERSION'] = '4'
+      ENV["VERBOSE"] = "false"
+      ENV["VERSION"] = "4"
+      ActiveRecord::Migrator.expects(:migrate).with("custom/path", 4)
+      ActiveRecord::Migration.expects(:verbose=).with(false)
+      ActiveRecord::Migration.expects(:verbose=).with(ActiveRecord::Migration.verbose)
+      ActiveRecord::Tasks::DatabaseTasks.migrate
 
-      ActiveRecord::Migrator.expects(:migrate).with('custom/path', 4)
+      ENV.delete("VERBOSE")
+      ENV.delete("VERSION")
+      ActiveRecord::Migrator.expects(:migrate).with("custom/path", nil)
+      ActiveRecord::Migration.expects(:verbose=).with(true)
+      ActiveRecord::Migration.expects(:verbose=).with(ActiveRecord::Migration.verbose)
       ActiveRecord::Tasks::DatabaseTasks.migrate
+
+      ENV["VERBOSE"] = ""
+      ENV["VERSION"] = ""
+      ActiveRecord::Migrator.expects(:migrate).with("custom/path", nil)
+      ActiveRecord::Migration.expects(:verbose=).with(true)
+      ActiveRecord::Migration.expects(:verbose=).with(ActiveRecord::Migration.verbose)
+      ActiveRecord::Tasks::DatabaseTasks.migrate
+
+      ENV["VERBOSE"] = "yes"
+      ENV["VERSION"] = "0"
+      ActiveRecord::Migrator.expects(:migrate).with("custom/path", 0)
+      ActiveRecord::Migration.expects(:verbose=).with(true)
+      ActiveRecord::Migration.expects(:verbose=).with(ActiveRecord::Migration.verbose)
+      ActiveRecord::Tasks::DatabaseTasks.migrate
+    ensure
+      ENV["VERBOSE"], ENV["VERSION"] = verbose, version
+    end
+
+    def test_migrate_raise_error_on_invalid_version_format
+      version = ENV["VERSION"]
+
+      ENV["VERSION"] = "unknown"
+      e = assert_raise(RuntimeError) { ActiveRecord::Tasks::DatabaseTasks.migrate }
+      assert_match(/Invalid format of target version/, e.message)
+
+      ENV["VERSION"] = "0.1.11"
+      e = assert_raise(RuntimeError) { ActiveRecord::Tasks::DatabaseTasks.migrate }
+      assert_match(/Invalid format of target version/, e.message)
+
+      ENV["VERSION"] = "1.1.11"
+      e = assert_raise(RuntimeError) { ActiveRecord::Tasks::DatabaseTasks.migrate }
+      assert_match(/Invalid format of target version/, e.message)
+
+      ENV["VERSION"] = "0 "
+      e = assert_raise(RuntimeError) { ActiveRecord::Tasks::DatabaseTasks.migrate }
+      assert_match(/Invalid format of target version/, e.message)
+
+      ENV["VERSION"] = "1."
+      e = assert_raise(RuntimeError) { ActiveRecord::Tasks::DatabaseTasks.migrate }
+      assert_match(/Invalid format of target version/, e.message)
+
+      ENV["VERSION"] = "1_"
+      e = assert_raise(RuntimeError) { ActiveRecord::Tasks::DatabaseTasks.migrate }
+      assert_match(/Invalid format of target version/, e.message)
+
+      ENV["VERSION"] = "1_name"
+      e = assert_raise(RuntimeError) { ActiveRecord::Tasks::DatabaseTasks.migrate }
+      assert_match(/Invalid format of target version/, e.message)
     ensure
-      ENV['VERBOSE'], ENV['VERSION'] = verbose, version
+      ENV["VERSION"] = version
+    end
+
+    def test_migrate_raise_error_on_failed_check_target_version
+      ActiveRecord::Tasks::DatabaseTasks.stubs(:check_target_version).raises("foo")
+
+      e = assert_raise(RuntimeError) { ActiveRecord::Tasks::DatabaseTasks.migrate }
+      assert_equal "foo", e.message
     end
 
     def test_migrate_clears_schema_cache_afterward
@@ -350,7 +445,7 @@ module ActiveRecord
     ADAPTERS_TASKS.each do |k, v|
       define_method("test_#{k}_purge") do
         eval("@#{v}").expects(:purge)
-        ActiveRecord::Tasks::DatabaseTasks.purge 'adapter' => k
+        ActiveRecord::Tasks::DatabaseTasks.purge "adapter" => k
       end
     end
   end
@@ -358,27 +453,27 @@ module ActiveRecord
   class DatabaseTasksPurgeCurrentTest < ActiveRecord::TestCase
     def test_purges_current_environment_database
       configurations = {
-        'development' => {'database' => 'dev-db'},
-        'test'        => {'database' => 'test-db'},
-        'production'  => {'database' => 'prod-db'}
+        "development" => { "database" => "dev-db" },
+        "test"        => { "database" => "test-db" },
+        "production"  => { "database" => "prod-db" }
       }
       ActiveRecord::Base.stubs(:configurations).returns(configurations)
 
       ActiveRecord::Tasks::DatabaseTasks.expects(:purge).
-        with('database' => 'prod-db')
+        with("database" => "prod-db")
       ActiveRecord::Base.expects(:establish_connection).with(:production)
 
-      ActiveRecord::Tasks::DatabaseTasks.purge_current('production')
+      ActiveRecord::Tasks::DatabaseTasks.purge_current("production")
     end
   end
 
   class DatabaseTasksPurgeAllTest < ActiveRecord::TestCase
     def test_purge_all_local_configurations
-      configurations = {:development => {'database' => 'my-db'}}
+      configurations = { development: { "database" => "my-db" } }
       ActiveRecord::Base.stubs(:configurations).returns(configurations)
 
       ActiveRecord::Tasks::DatabaseTasks.expects(:purge).
-        with('database' => 'my-db')
+        with("database" => "my-db")
 
       ActiveRecord::Tasks::DatabaseTasks.purge_all
     end
@@ -390,7 +485,7 @@ module ActiveRecord
     ADAPTERS_TASKS.each do |k, v|
       define_method("test_#{k}_charset") do
         eval("@#{v}").expects(:charset)
-        ActiveRecord::Tasks::DatabaseTasks.charset 'adapter' => k
+        ActiveRecord::Tasks::DatabaseTasks.charset "adapter" => k
       end
     end
   end
@@ -401,18 +496,120 @@ module ActiveRecord
     ADAPTERS_TASKS.each do |k, v|
       define_method("test_#{k}_collation") do
         eval("@#{v}").expects(:collation)
-        ActiveRecord::Tasks::DatabaseTasks.collation 'adapter' => k
+        ActiveRecord::Tasks::DatabaseTasks.collation "adapter" => k
       end
     end
   end
 
+  class DatabaseTaskTargetVersionTest < ActiveRecord::TestCase
+    def test_target_version_returns_nil_if_version_does_not_exist
+      version = ENV.delete("VERSION")
+      assert_nil ActiveRecord::Tasks::DatabaseTasks.target_version
+    ensure
+      ENV["VERSION"] = version
+    end
+
+    def test_target_version_returns_nil_if_version_is_empty
+      version = ENV["VERSION"]
+
+      ENV["VERSION"] = ""
+      assert_nil ActiveRecord::Tasks::DatabaseTasks.target_version
+    ensure
+      ENV["VERSION"] = version
+    end
+
+    def test_target_version_returns_converted_to_integer_env_version_if_version_exists
+      version = ENV["VERSION"]
+
+      ENV["VERSION"] = "0"
+      assert_equal ENV["VERSION"].to_i, ActiveRecord::Tasks::DatabaseTasks.target_version
+
+      ENV["VERSION"] = "42"
+      assert_equal ENV["VERSION"].to_i, ActiveRecord::Tasks::DatabaseTasks.target_version
+
+      ENV["VERSION"] = "042"
+      assert_equal ENV["VERSION"].to_i, ActiveRecord::Tasks::DatabaseTasks.target_version
+    ensure
+      ENV["VERSION"] = version
+    end
+  end
+
+  class DatabaseTaskCheckTargetVersionTest < ActiveRecord::TestCase
+    def test_check_target_version_does_not_raise_error_on_empty_version
+      version = ENV["VERSION"]
+      ENV["VERSION"] = ""
+      assert_nothing_raised { ActiveRecord::Tasks::DatabaseTasks.check_target_version }
+    ensure
+      ENV["VERSION"] = version
+    end
+
+    def test_check_target_version_does_not_raise_error_if_version_is_not_setted
+      version = ENV.delete("VERSION")
+      assert_nothing_raised { ActiveRecord::Tasks::DatabaseTasks.check_target_version }
+    ensure
+      ENV["VERSION"] = version
+    end
+
+    def test_check_target_version_raises_error_on_invalid_version_format
+      version = ENV["VERSION"]
+
+      ENV["VERSION"] = "unknown"
+      e = assert_raise(RuntimeError) { ActiveRecord::Tasks::DatabaseTasks.check_target_version }
+      assert_match(/Invalid format of target version/, e.message)
+
+      ENV["VERSION"] = "0.1.11"
+      e = assert_raise(RuntimeError) { ActiveRecord::Tasks::DatabaseTasks.check_target_version }
+      assert_match(/Invalid format of target version/, e.message)
+
+      ENV["VERSION"] = "1.1.11"
+      e = assert_raise(RuntimeError) { ActiveRecord::Tasks::DatabaseTasks.check_target_version }
+      assert_match(/Invalid format of target version/, e.message)
+
+      ENV["VERSION"] = "0 "
+      e = assert_raise(RuntimeError) { ActiveRecord::Tasks::DatabaseTasks.check_target_version }
+      assert_match(/Invalid format of target version/, e.message)
+
+      ENV["VERSION"] = "1."
+      e = assert_raise(RuntimeError) { ActiveRecord::Tasks::DatabaseTasks.check_target_version }
+      assert_match(/Invalid format of target version/, e.message)
+
+      ENV["VERSION"] = "1_"
+      e = assert_raise(RuntimeError) { ActiveRecord::Tasks::DatabaseTasks.check_target_version }
+      assert_match(/Invalid format of target version/, e.message)
+
+      ENV["VERSION"] = "1_name"
+      e = assert_raise(RuntimeError) { ActiveRecord::Tasks::DatabaseTasks.check_target_version }
+      assert_match(/Invalid format of target version/, e.message)
+    ensure
+      ENV["VERSION"] = version
+    end
+
+    def test_check_target_version_does_not_raise_error_on_valid_version_format
+      version = ENV["VERSION"]
+
+      ENV["VERSION"] = "0"
+      assert_nothing_raised { ActiveRecord::Tasks::DatabaseTasks.check_target_version }
+
+      ENV["VERSION"] = "1"
+      assert_nothing_raised { ActiveRecord::Tasks::DatabaseTasks.check_target_version }
+
+      ENV["VERSION"] = "001"
+      assert_nothing_raised { ActiveRecord::Tasks::DatabaseTasks.check_target_version }
+
+      ENV["VERSION"] = "001_name.rb"
+      assert_nothing_raised { ActiveRecord::Tasks::DatabaseTasks.check_target_version }
+    ensure
+      ENV["VERSION"] = version
+    end
+  end
+
   class DatabaseTasksStructureDumpTest < ActiveRecord::TestCase
     include DatabaseTasksSetupper
 
     ADAPTERS_TASKS.each do |k, v|
       define_method("test_#{k}_structure_dump") do
-        eval("@#{v}").expects(:structure_dump).with("awesome-file.sql")
-        ActiveRecord::Tasks::DatabaseTasks.structure_dump({'adapter' => k}, "awesome-file.sql")
+        eval("@#{v}").expects(:structure_dump).with("awesome-file.sql", nil)
+        ActiveRecord::Tasks::DatabaseTasks.structure_dump({ "adapter" => k }, "awesome-file.sql")
       end
     end
   end
@@ -422,8 +619,8 @@ module ActiveRecord
 
     ADAPTERS_TASKS.each do |k, v|
       define_method("test_#{k}_structure_load") do
-        eval("@#{v}").expects(:structure_load).with("awesome-file.sql")
-        ActiveRecord::Tasks::DatabaseTasks.structure_load({'adapter' => k}, "awesome-file.sql")
+        eval("@#{v}").expects(:structure_load).with("awesome-file.sql", nil)
+        ActiveRecord::Tasks::DatabaseTasks.structure_load({ "adapter" => k }, "awesome-file.sql")
       end
     end
   end
@@ -437,15 +634,15 @@ module ActiveRecord
 
   class DatabaseTasksCheckSchemaFileDefaultsTest < ActiveRecord::TestCase
     def test_check_schema_file_defaults
-      ActiveRecord::Tasks::DatabaseTasks.stubs(:db_dir).returns('/tmp')
-      assert_equal '/tmp/schema.rb', ActiveRecord::Tasks::DatabaseTasks.schema_file
+      ActiveRecord::Tasks::DatabaseTasks.stubs(:db_dir).returns("/tmp")
+      assert_equal "/tmp/schema.rb", ActiveRecord::Tasks::DatabaseTasks.schema_file
     end
   end
 
   class DatabaseTasksCheckSchemaFileSpecifiedFormatsTest < ActiveRecord::TestCase
-    {ruby: 'schema.rb', sql: 'structure.sql'}.each_pair do |fmt, filename|
+    { ruby: "schema.rb", sql: "structure.sql" }.each_pair do |fmt, filename|
       define_method("test_check_schema_file_for_#{fmt}_format") do
-        ActiveRecord::Tasks::DatabaseTasks.stubs(:db_dir).returns('/tmp')
+        ActiveRecord::Tasks::DatabaseTasks.stubs(:db_dir).returns("/tmp")
         assert_equal "/tmp/#{filename}", ActiveRecord::Tasks::DatabaseTasks.schema_file(fmt)
       end
     end
diff --git a/activerecord/test/cases/tasks/mysql_rake_test.rb b/activerecord/test/cases/tasks/mysql_rake_test.rb
index 70e406038f..047153e7cc 100644
--- a/activerecord/test/cases/tasks/mysql_rake_test.rb
+++ b/activerecord/test/cases/tasks/mysql_rake_test.rb
@@ -1,345 +1,319 @@
-require 'cases/helper'
-require 'active_record/tasks/database_tasks'
+# frozen_string_literal: true
+
+require "cases/helper"
+require "active_record/tasks/database_tasks"
 
 if current_adapter?(:Mysql2Adapter)
-module ActiveRecord
-  class MysqlDBCreateTest < ActiveRecord::TestCase
-    def setup
-      @connection    = stub(:create_database => true)
-      @configuration = {
-        'adapter'  => 'mysql2',
-        'database' => 'my-app-db'
-      }
-
-      ActiveRecord::Base.stubs(:connection).returns(@connection)
-      ActiveRecord::Base.stubs(:establish_connection).returns(true)
-
-      $stdout, @original_stdout = StringIO.new, $stdout
-      $stderr, @original_stderr = StringIO.new, $stderr
-    end
+  module ActiveRecord
+    class MysqlDBCreateTest < ActiveRecord::TestCase
+      def setup
+        @connection    = stub(create_database: true)
+        @configuration = {
+          "adapter"  => "mysql2",
+          "database" => "my-app-db"
+        }
+
+        ActiveRecord::Base.stubs(:connection).returns(@connection)
+        ActiveRecord::Base.stubs(:establish_connection).returns(true)
+
+        $stdout, @original_stdout = StringIO.new, $stdout
+        $stderr, @original_stderr = StringIO.new, $stderr
+      end
 
-    def teardown
-      $stdout, $stderr = @original_stdout, @original_stderr
-    end
+      def teardown
+        $stdout, $stderr = @original_stdout, @original_stderr
+      end
 
-    def test_establishes_connection_without_database
-      ActiveRecord::Base.expects(:establish_connection).
-        with('adapter' => 'mysql2', 'database' => nil)
+      def test_establishes_connection_without_database
+        ActiveRecord::Base.expects(:establish_connection).
+          with("adapter" => "mysql2", "database" => nil)
 
-      ActiveRecord::Tasks::DatabaseTasks.create @configuration
-    end
-
-    def test_creates_database_with_no_default_options
-      @connection.expects(:create_database).
-        with('my-app-db', {})
+        ActiveRecord::Tasks::DatabaseTasks.create @configuration
+      end
 
-      ActiveRecord::Tasks::DatabaseTasks.create @configuration
-    end
+      def test_creates_database_with_no_default_options
+        @connection.expects(:create_database).
+          with("my-app-db", {})
 
-    def test_creates_database_with_given_encoding
-      @connection.expects(:create_database).
-        with('my-app-db', charset: 'latin1')
+        ActiveRecord::Tasks::DatabaseTasks.create @configuration
+      end
 
-      ActiveRecord::Tasks::DatabaseTasks.create @configuration.merge('encoding' => 'latin1')
-    end
+      def test_creates_database_with_given_encoding
+        @connection.expects(:create_database).
+          with("my-app-db", charset: "latin1")
 
-    def test_creates_database_with_given_collation
-      @connection.expects(:create_database).
-        with('my-app-db', collation: 'latin1_swedish_ci')
+        ActiveRecord::Tasks::DatabaseTasks.create @configuration.merge("encoding" => "latin1")
+      end
 
-      ActiveRecord::Tasks::DatabaseTasks.create @configuration.merge('collation' => 'latin1_swedish_ci')
-    end
+      def test_creates_database_with_given_collation
+        @connection.expects(:create_database).
+          with("my-app-db", collation: "latin1_swedish_ci")
 
-    def test_establishes_connection_to_database
-      ActiveRecord::Base.expects(:establish_connection).with(@configuration)
+        ActiveRecord::Tasks::DatabaseTasks.create @configuration.merge("collation" => "latin1_swedish_ci")
+      end
 
-      ActiveRecord::Tasks::DatabaseTasks.create @configuration
-    end
+      def test_establishes_connection_to_database
+        ActiveRecord::Base.expects(:establish_connection).with(@configuration)
 
-    def test_when_database_created_successfully_outputs_info_to_stdout
-      ActiveRecord::Tasks::DatabaseTasks.create @configuration
+        ActiveRecord::Tasks::DatabaseTasks.create @configuration
+      end
 
-      assert_equal $stdout.string, "Created database 'my-app-db'\n"
-    end
+      def test_when_database_created_successfully_outputs_info_to_stdout
+        ActiveRecord::Tasks::DatabaseTasks.create @configuration
 
-    def test_create_when_database_exists_outputs_info_to_stderr
-      ActiveRecord::Base.connection.stubs(:create_database).raises(
-        ActiveRecord::Tasks::DatabaseAlreadyExists
-      )
+        assert_equal "Created database 'my-app-db'\n", $stdout.string
+      end
 
-      ActiveRecord::Tasks::DatabaseTasks.create @configuration
+      def test_create_when_database_exists_outputs_info_to_stderr
+        ActiveRecord::Base.connection.stubs(:create_database).raises(
+          ActiveRecord::Tasks::DatabaseAlreadyExists
+        )
 
-      assert_equal $stderr.string, "Database 'my-app-db' already exists\n"
-    end
-  end
+        ActiveRecord::Tasks::DatabaseTasks.create @configuration
 
-  class MysqlDBCreateAsRootTest < ActiveRecord::TestCase
-    def setup
-      @connection    = stub("Connection", create_database: true)
-      @error         = Mysql2::Error.new("Invalid permissions")
-      @configuration = {
-        'adapter'  => 'mysql2',
-        'database' => 'my-app-db',
-        'username' => 'pat',
-        'password' => 'wossname'
-      }
-
-      $stdin.stubs(:gets).returns("secret\n")
-      $stdout.stubs(:print).returns(nil)
-      @error.stubs(:errno).returns(1045)
-      ActiveRecord::Base.stubs(:connection).returns(@connection)
-      ActiveRecord::Base.stubs(:establish_connection).
-        raises(@error).
-        then.returns(true)
-
-      $stdout, @original_stdout = StringIO.new, $stdout
-      $stderr, @original_stderr = StringIO.new, $stderr
-    end
-
-    def teardown
-      $stdout, $stderr = @original_stdout, @original_stderr
+        assert_equal "Database 'my-app-db' already exists\n", $stderr.string
+      end
     end
 
-    def test_root_password_is_requested
-      assert_permissions_granted_for("pat")
-      $stdin.expects(:gets).returns("secret\n")
-
-      ActiveRecord::Tasks::DatabaseTasks.create @configuration
-    end
+    class MysqlDBCreateWithInvalidPermissionsTest < ActiveRecord::TestCase
+      def setup
+        @connection    = stub("Connection", create_database: true)
+        @error         = Mysql2::Error.new("Invalid permissions")
+        @configuration = {
+          "adapter"  => "mysql2",
+          "database" => "my-app-db",
+          "username" => "pat",
+          "password" => "wossname"
+        }
 
-    def test_connection_established_as_root
-      assert_permissions_granted_for("pat")
-      ActiveRecord::Base.expects(:establish_connection).with(
-        'adapter'  => 'mysql2',
-        'database' => nil,
-        'username' => 'root',
-        'password' => 'secret'
-      )
+        ActiveRecord::Base.stubs(:connection).returns(@connection)
+        ActiveRecord::Base.stubs(:establish_connection).raises(@error)
 
-      ActiveRecord::Tasks::DatabaseTasks.create @configuration
-    end
+        $stdout, @original_stdout = StringIO.new, $stdout
+        $stderr, @original_stderr = StringIO.new, $stderr
+      end
 
-    def test_database_created_by_root
-      assert_permissions_granted_for("pat")
-      @connection.expects(:create_database).
-        with('my-app-db', {})
+      def teardown
+        $stdout, $stderr = @original_stdout, @original_stderr
+      end
 
-      ActiveRecord::Tasks::DatabaseTasks.create @configuration
+      def test_raises_error
+        assert_raises(Mysql2::Error) do
+          ActiveRecord::Tasks::DatabaseTasks.create @configuration
+        end
+      end
     end
 
-    def test_grant_privileges_for_normal_user
-      assert_permissions_granted_for("pat")
-      ActiveRecord::Tasks::DatabaseTasks.create @configuration
-    end
+    class MySQLDBDropTest < ActiveRecord::TestCase
+      def setup
+        @connection    = stub(drop_database: true)
+        @configuration = {
+          "adapter"  => "mysql2",
+          "database" => "my-app-db"
+        }
 
-    def test_do_not_grant_privileges_for_root_user
-      @configuration['username'] = 'root'
-      @configuration['password'] = ''
-      ActiveRecord::Tasks::DatabaseTasks.create @configuration
-    end
+        ActiveRecord::Base.stubs(:connection).returns(@connection)
+        ActiveRecord::Base.stubs(:establish_connection).returns(true)
 
-    def test_connection_established_as_normal_user
-      assert_permissions_granted_for("pat")
-      ActiveRecord::Base.expects(:establish_connection).returns do
-        ActiveRecord::Base.expects(:establish_connection).with(
-          'adapter'  => 'mysql2',
-          'database' => 'my-app-db',
-          'username' => 'pat',
-          'password' => 'secret'
-        )
+        $stdout, @original_stdout = StringIO.new, $stdout
+        $stderr, @original_stderr = StringIO.new, $stderr
+      end
 
-        raise @error
+      def teardown
+        $stdout, $stderr = @original_stdout, @original_stderr
       end
 
-      ActiveRecord::Tasks::DatabaseTasks.create @configuration
-    end
+      def test_establishes_connection_to_mysql_database
+        ActiveRecord::Base.expects(:establish_connection).with @configuration
 
-    def test_sends_output_to_stderr_when_other_errors
-      @error.stubs(:errno).returns(42)
+        ActiveRecord::Tasks::DatabaseTasks.drop @configuration
+      end
 
-      $stderr.expects(:puts).at_least_once.returns(nil)
+      def test_drops_database
+        @connection.expects(:drop_database).with("my-app-db")
 
-      ActiveRecord::Tasks::DatabaseTasks.create @configuration
-    end
+        ActiveRecord::Tasks::DatabaseTasks.drop @configuration
+      end
 
-    private
+      def test_when_database_dropped_successfully_outputs_info_to_stdout
+        ActiveRecord::Tasks::DatabaseTasks.drop @configuration
 
-    def assert_permissions_granted_for(db_user)
-      db_name = @configuration['database']
-      db_password = @configuration['password']
-      @connection.expects(:execute).with("GRANT ALL PRIVILEGES ON #{db_name}.* TO '#{db_user}'@'localhost' IDENTIFIED BY '#{db_password}' WITH GRANT OPTION;")
+        assert_equal "Dropped database 'my-app-db'\n", $stdout.string
+      end
     end
-  end
-
-  class MySQLDBDropTest < ActiveRecord::TestCase
-    def setup
-      @connection    = stub(:drop_database => true)
-      @configuration = {
-        'adapter'  => 'mysql2',
-        'database' => 'my-app-db'
-      }
 
-      ActiveRecord::Base.stubs(:connection).returns(@connection)
-      ActiveRecord::Base.stubs(:establish_connection).returns(true)
-
-      $stdout, @original_stdout = StringIO.new, $stdout
-      $stderr, @original_stderr = StringIO.new, $stderr
-    end
+    class MySQLPurgeTest < ActiveRecord::TestCase
+      def setup
+        @connection    = stub(recreate_database: true)
+        @configuration = {
+          "adapter"  => "mysql2",
+          "database" => "test-db"
+        }
 
-    def teardown
-      $stdout, $stderr = @original_stdout, @original_stderr
-    end
+        ActiveRecord::Base.stubs(:connection).returns(@connection)
+        ActiveRecord::Base.stubs(:establish_connection).returns(true)
+      end
 
-    def test_establishes_connection_to_mysql_database
-      ActiveRecord::Base.expects(:establish_connection).with @configuration
+      def test_establishes_connection_to_the_appropriate_database
+        ActiveRecord::Base.expects(:establish_connection).with(@configuration)
 
-      ActiveRecord::Tasks::DatabaseTasks.drop @configuration
-    end
+        ActiveRecord::Tasks::DatabaseTasks.purge @configuration
+      end
 
-    def test_drops_database
-      @connection.expects(:drop_database).with('my-app-db')
+      def test_recreates_database_with_no_default_options
+        @connection.expects(:recreate_database).
+          with("test-db", {})
 
-      ActiveRecord::Tasks::DatabaseTasks.drop @configuration
-    end
+        ActiveRecord::Tasks::DatabaseTasks.purge @configuration
+      end
 
-    def test_when_database_dropped_successfully_outputs_info_to_stdout
-      ActiveRecord::Tasks::DatabaseTasks.drop @configuration
+      def test_recreates_database_with_the_given_options
+        @connection.expects(:recreate_database).
+          with("test-db", charset: "latin", collation: "latin1_swedish_ci")
 
-      assert_equal $stdout.string, "Dropped database 'my-app-db'\n"
+        ActiveRecord::Tasks::DatabaseTasks.purge @configuration.merge(
+          "encoding" => "latin", "collation" => "latin1_swedish_ci")
+      end
     end
-  end
 
-  class MySQLPurgeTest < ActiveRecord::TestCase
-    def setup
-      @connection    = stub(:recreate_database => true)
-      @configuration = {
-        'adapter'  => 'mysql2',
-        'database' => 'test-db'
-      }
+    class MysqlDBCharsetTest < ActiveRecord::TestCase
+      def setup
+        @connection    = stub(create_database: true)
+        @configuration = {
+          "adapter"  => "mysql2",
+          "database" => "my-app-db"
+        }
 
-      ActiveRecord::Base.stubs(:connection).returns(@connection)
-      ActiveRecord::Base.stubs(:establish_connection).returns(true)
-    end
-
-    def test_establishes_connection_to_the_appropriate_database
-      ActiveRecord::Base.expects(:establish_connection).with(@configuration)
+        ActiveRecord::Base.stubs(:connection).returns(@connection)
+        ActiveRecord::Base.stubs(:establish_connection).returns(true)
+      end
 
-      ActiveRecord::Tasks::DatabaseTasks.purge @configuration
+      def test_db_retrieves_charset
+        @connection.expects(:charset)
+        ActiveRecord::Tasks::DatabaseTasks.charset @configuration
+      end
     end
 
-    def test_recreates_database_with_no_default_options
-      @connection.expects(:recreate_database).
-        with('test-db', {})
-
-      ActiveRecord::Tasks::DatabaseTasks.purge @configuration
-    end
+    class MysqlDBCollationTest < ActiveRecord::TestCase
+      def setup
+        @connection    = stub(create_database: true)
+        @configuration = {
+          "adapter"  => "mysql2",
+          "database" => "my-app-db"
+        }
 
-    def test_recreates_database_with_the_given_options
-      @connection.expects(:recreate_database).
-        with('test-db', charset: 'latin', collation: 'latin1_swedish_ci')
+        ActiveRecord::Base.stubs(:connection).returns(@connection)
+        ActiveRecord::Base.stubs(:establish_connection).returns(true)
+      end
 
-      ActiveRecord::Tasks::DatabaseTasks.purge @configuration.merge(
-        'encoding' => 'latin', 'collation' => 'latin1_swedish_ci')
+      def test_db_retrieves_collation
+        @connection.expects(:collation)
+        ActiveRecord::Tasks::DatabaseTasks.collation @configuration
+      end
     end
-  end
 
-  class MysqlDBCharsetTest < ActiveRecord::TestCase
-    def setup
-      @connection    = stub(:create_database => true)
-      @configuration = {
-        'adapter'  => 'mysql2',
-        'database' => 'my-app-db'
-      }
+    class MySQLStructureDumpTest < ActiveRecord::TestCase
+      def setup
+        @configuration = {
+          "adapter"  => "mysql2",
+          "database" => "test-db"
+        }
+      end
 
-      ActiveRecord::Base.stubs(:connection).returns(@connection)
-      ActiveRecord::Base.stubs(:establish_connection).returns(true)
-    end
+      def test_structure_dump
+        filename = "awesome-file.sql"
+        Kernel.expects(:system).with("mysqldump", "--result-file", filename, "--no-data", "--routines", "--skip-comments", "test-db").returns(true)
 
-    def test_db_retrieves_charset
-      @connection.expects(:charset)
-      ActiveRecord::Tasks::DatabaseTasks.charset @configuration
-    end
-  end
+        ActiveRecord::Tasks::DatabaseTasks.structure_dump(@configuration, filename)
+      end
 
-  class MysqlDBCollationTest < ActiveRecord::TestCase
-    def setup
-      @connection    = stub(:create_database => true)
-      @configuration = {
-        'adapter'  => 'mysql2',
-        'database' => 'my-app-db'
-      }
+      def test_structure_dump_with_extra_flags
+        filename = "awesome-file.sql"
+        expected_command = ["mysqldump", "--noop", "--result-file", filename, "--no-data", "--routines", "--skip-comments", "test-db"]
 
-      ActiveRecord::Base.stubs(:connection).returns(@connection)
-      ActiveRecord::Base.stubs(:establish_connection).returns(true)
-    end
+        assert_called_with(Kernel, :system, expected_command, returns: true) do
+          with_structure_dump_flags(["--noop"]) do
+            ActiveRecord::Tasks::DatabaseTasks.structure_dump(@configuration, filename)
+          end
+        end
+      end
 
-    def test_db_retrieves_collation
-      @connection.expects(:collation)
-      ActiveRecord::Tasks::DatabaseTasks.collation @configuration
-    end
-  end
+      def test_structure_dump_with_ignore_tables
+        filename = "awesome-file.sql"
+        ActiveRecord::SchemaDumper.expects(:ignore_tables).returns(["foo", "bar"])
 
-  class MySQLStructureDumpTest < ActiveRecord::TestCase
-    def setup
-      @configuration = {
-        'adapter'  => 'mysql2',
-        'database' => 'test-db'
-      }
-    end
+        Kernel.expects(:system).with("mysqldump", "--result-file", filename, "--no-data", "--routines", "--skip-comments", "--ignore-table=test-db.foo", "--ignore-table=test-db.bar", "test-db").returns(true)
 
-    def test_structure_dump
-      filename = "awesome-file.sql"
-      Kernel.expects(:system).with("mysqldump", "--result-file", filename, "--no-data", "--routines", "--skip-comments", "test-db").returns(true)
+        ActiveRecord::Tasks::DatabaseTasks.structure_dump(@configuration, filename)
+      end
 
-      ActiveRecord::Tasks::DatabaseTasks.structure_dump(@configuration, filename)
-    end
+      def test_warn_when_external_structure_dump_command_execution_fails
+        filename = "awesome-file.sql"
+        Kernel.expects(:system)
+          .with("mysqldump", "--result-file", filename, "--no-data", "--routines", "--skip-comments", "test-db")
+          .returns(false)
 
-    def test_warn_when_external_structure_dump_command_execution_fails
-      filename = "awesome-file.sql"
-      Kernel.expects(:system)
-        .with("mysqldump", "--result-file", filename, "--no-data", "--routines", "--skip-comments", "test-db")
-        .returns(false)
+        e = assert_raise(RuntimeError) {
+          ActiveRecord::Tasks::DatabaseTasks.structure_dump(@configuration, filename)
+        }
+        assert_match(/^failed to execute: `mysqldump`$/, e.message)
+      end
 
-      e = assert_raise(RuntimeError) {
-        ActiveRecord::Tasks::DatabaseTasks.structure_dump(@configuration, filename)
-      }
-      assert_match(/^failed to execute: `mysqldump`$/, e.message)
-    end
+      def test_structure_dump_with_port_number
+        filename = "awesome-file.sql"
+        Kernel.expects(:system).with("mysqldump", "--port=10000", "--result-file", filename, "--no-data", "--routines", "--skip-comments", "test-db").returns(true)
 
-    def test_structure_dump_with_port_number
-      filename = "awesome-file.sql"
-      Kernel.expects(:system).with("mysqldump", "--port=10000", "--result-file", filename, "--no-data", "--routines", "--skip-comments", "test-db").returns(true)
+        ActiveRecord::Tasks::DatabaseTasks.structure_dump(
+          @configuration.merge("port" => 10000),
+          filename)
+      end
 
-      ActiveRecord::Tasks::DatabaseTasks.structure_dump(
-        @configuration.merge('port' => 10000),
-        filename)
-    end
+      def test_structure_dump_with_ssl
+        filename = "awesome-file.sql"
+        Kernel.expects(:system).with("mysqldump", "--ssl-ca=ca.crt", "--result-file", filename, "--no-data", "--routines", "--skip-comments", "test-db").returns(true)
 
-    def test_structure_dump_with_ssl
-      filename = "awesome-file.sql"
-      Kernel.expects(:system).with("mysqldump", "--ssl-ca=ca.crt", "--result-file", filename, "--no-data", "--routines", "--skip-comments", "test-db").returns(true)
+        ActiveRecord::Tasks::DatabaseTasks.structure_dump(
+          @configuration.merge("sslca" => "ca.crt"),
+          filename)
+      end
 
-      ActiveRecord::Tasks::DatabaseTasks.structure_dump(
-        @configuration.merge("sslca" => "ca.crt"),
-        filename)
-    end
-  end
+      private
+        def with_structure_dump_flags(flags)
+          old = ActiveRecord::Tasks::DatabaseTasks.structure_dump_flags
+          ActiveRecord::Tasks::DatabaseTasks.structure_dump_flags = flags
+          yield
+        ensure
+          ActiveRecord::Tasks::DatabaseTasks.structure_dump_flags = old
+        end
+    end
+
+    class MySQLStructureLoadTest < ActiveRecord::TestCase
+      def setup
+        @configuration = {
+          "adapter"  => "mysql2",
+          "database" => "test-db"
+        }
+      end
 
-  class MySQLStructureLoadTest < ActiveRecord::TestCase
-    def setup
-      @configuration = {
-        'adapter'  => 'mysql2',
-        'database' => 'test-db'
-      }
-    end
+      def test_structure_load
+        filename = "awesome-file.sql"
+        expected_command = ["mysql", "--noop", "--execute", %{SET FOREIGN_KEY_CHECKS = 0; SOURCE #{filename}; SET FOREIGN_KEY_CHECKS = 1}, "--database", "test-db"]
 
-    def test_structure_load
-      filename = "awesome-file.sql"
-      Kernel.expects(:system).with('mysql', '--execute', %{SET FOREIGN_KEY_CHECKS = 0; SOURCE #{filename}; SET FOREIGN_KEY_CHECKS = 1}, "--database", "test-db")
-        .returns(true)
+        assert_called_with(Kernel, :system, expected_command, returns: true) do
+          with_structure_load_flags(["--noop"]) do
+            ActiveRecord::Tasks::DatabaseTasks.structure_load(@configuration, filename)
+          end
+        end
+      end
 
-      ActiveRecord::Tasks::DatabaseTasks.structure_load(@configuration, filename)
+      private
+        def with_structure_load_flags(flags)
+          old = ActiveRecord::Tasks::DatabaseTasks.structure_load_flags
+          ActiveRecord::Tasks::DatabaseTasks.structure_load_flags = flags
+          yield
+        ensure
+          ActiveRecord::Tasks::DatabaseTasks.structure_load_flags = old
+        end
     end
   end
 end
-end
diff --git a/activerecord/test/cases/tasks/postgresql_rake_test.rb b/activerecord/test/cases/tasks/postgresql_rake_test.rb
index 99d73e91a4..ca1defa332 100644
--- a/activerecord/test/cases/tasks/postgresql_rake_test.rb
+++ b/activerecord/test/cases/tasks/postgresql_rake_test.rb
@@ -1,304 +1,372 @@
-require 'cases/helper'
-require 'active_record/tasks/database_tasks'
+# frozen_string_literal: true
+
+require "cases/helper"
+require "active_record/tasks/database_tasks"
 
 if current_adapter?(:PostgreSQLAdapter)
-module ActiveRecord
-  class PostgreSQLDBCreateTest < ActiveRecord::TestCase
-    def setup
-      @connection    = stub(:create_database => true)
-      @configuration = {
-        'adapter'  => 'postgresql',
-        'database' => 'my-app-db'
-      }
-
-      ActiveRecord::Base.stubs(:connection).returns(@connection)
-      ActiveRecord::Base.stubs(:establish_connection).returns(true)
-
-      $stdout, @original_stdout = StringIO.new, $stdout
-      $stderr, @original_stderr = StringIO.new, $stderr
-    end
+  module ActiveRecord
+    class PostgreSQLDBCreateTest < ActiveRecord::TestCase
+      def setup
+        @connection    = stub(create_database: true)
+        @configuration = {
+          "adapter"  => "postgresql",
+          "database" => "my-app-db"
+        }
+
+        ActiveRecord::Base.stubs(:connection).returns(@connection)
+        ActiveRecord::Base.stubs(:establish_connection).returns(true)
+
+        $stdout, @original_stdout = StringIO.new, $stdout
+        $stderr, @original_stderr = StringIO.new, $stderr
+      end
 
-    def teardown
-      $stdout, $stderr = @original_stdout, @original_stderr
-    end
+      def teardown
+        $stdout, $stderr = @original_stdout, @original_stderr
+      end
 
-    def test_establishes_connection_to_postgresql_database
-      ActiveRecord::Base.expects(:establish_connection).with(
-        'adapter'            => 'postgresql',
-        'database'           => 'postgres',
-        'schema_search_path' => 'public'
-      )
+      def test_establishes_connection_to_postgresql_database
+        ActiveRecord::Base.expects(:establish_connection).with(
+          "adapter"            => "postgresql",
+          "database"           => "postgres",
+          "schema_search_path" => "public"
+        )
 
-      ActiveRecord::Tasks::DatabaseTasks.create @configuration
-    end
+        ActiveRecord::Tasks::DatabaseTasks.create @configuration
+      end
 
-    def test_creates_database_with_default_encoding
-      @connection.expects(:create_database).
-        with('my-app-db', @configuration.merge('encoding' => 'utf8'))
+      def test_creates_database_with_default_encoding
+        @connection.expects(:create_database).
+          with("my-app-db", @configuration.merge("encoding" => "utf8"))
 
-      ActiveRecord::Tasks::DatabaseTasks.create @configuration
-    end
+        ActiveRecord::Tasks::DatabaseTasks.create @configuration
+      end
 
-    def test_creates_database_with_given_encoding
-      @connection.expects(:create_database).
-        with('my-app-db', @configuration.merge('encoding' => 'latin'))
+      def test_creates_database_with_given_encoding
+        @connection.expects(:create_database).
+          with("my-app-db", @configuration.merge("encoding" => "latin"))
 
-      ActiveRecord::Tasks::DatabaseTasks.create @configuration.
-        merge('encoding' => 'latin')
-    end
+        ActiveRecord::Tasks::DatabaseTasks.create @configuration.
+          merge("encoding" => "latin")
+      end
 
-    def test_creates_database_with_given_collation_and_ctype
-      @connection.expects(:create_database).
-        with('my-app-db', @configuration.merge('encoding' => 'utf8', 'collation' => 'ja_JP.UTF8', 'ctype' => 'ja_JP.UTF8'))
+      def test_creates_database_with_given_collation_and_ctype
+        @connection.expects(:create_database).
+          with("my-app-db", @configuration.merge("encoding" => "utf8", "collation" => "ja_JP.UTF8", "ctype" => "ja_JP.UTF8"))
 
-      ActiveRecord::Tasks::DatabaseTasks.create @configuration.
-        merge('collation' => 'ja_JP.UTF8', 'ctype' => 'ja_JP.UTF8')
-    end
+        ActiveRecord::Tasks::DatabaseTasks.create @configuration.
+          merge("collation" => "ja_JP.UTF8", "ctype" => "ja_JP.UTF8")
+      end
 
-    def test_establishes_connection_to_new_database
-      ActiveRecord::Base.expects(:establish_connection).with(@configuration)
+      def test_establishes_connection_to_new_database
+        ActiveRecord::Base.expects(:establish_connection).with(@configuration)
 
-      ActiveRecord::Tasks::DatabaseTasks.create @configuration
-    end
+        ActiveRecord::Tasks::DatabaseTasks.create @configuration
+      end
 
-    def test_db_create_with_error_prints_message
-      ActiveRecord::Base.stubs(:establish_connection).raises(Exception)
+      def test_db_create_with_error_prints_message
+        ActiveRecord::Base.stubs(:establish_connection).raises(Exception)
 
-      $stderr.stubs(:puts).returns(true)
-      $stderr.expects(:puts).
-        with("Couldn't create database for #{@configuration.inspect}")
+        $stderr.stubs(:puts).returns(true)
+        $stderr.expects(:puts).
+          with("Couldn't create database for #{@configuration.inspect}")
 
-      assert_raises(Exception) { ActiveRecord::Tasks::DatabaseTasks.create @configuration }
-    end
+        assert_raises(Exception) { ActiveRecord::Tasks::DatabaseTasks.create @configuration }
+      end
 
-    def test_when_database_created_successfully_outputs_info_to_stdout
-      ActiveRecord::Tasks::DatabaseTasks.create @configuration
+      def test_when_database_created_successfully_outputs_info_to_stdout
+        ActiveRecord::Tasks::DatabaseTasks.create @configuration
 
-      assert_equal $stdout.string, "Created database 'my-app-db'\n"
-    end
+        assert_equal "Created database 'my-app-db'\n", $stdout.string
+      end
 
-    def test_create_when_database_exists_outputs_info_to_stderr
-      ActiveRecord::Base.connection.stubs(:create_database).raises(
-        ActiveRecord::Tasks::DatabaseAlreadyExists
-      )
+      def test_create_when_database_exists_outputs_info_to_stderr
+        ActiveRecord::Base.connection.stubs(:create_database).raises(
+          ActiveRecord::Tasks::DatabaseAlreadyExists
+        )
 
-      ActiveRecord::Tasks::DatabaseTasks.create @configuration
+        ActiveRecord::Tasks::DatabaseTasks.create @configuration
 
-      assert_equal $stderr.string, "Database 'my-app-db' already exists\n"
+        assert_equal "Database 'my-app-db' already exists\n", $stderr.string
+      end
     end
-  end
 
-  class PostgreSQLDBDropTest < ActiveRecord::TestCase
-    def setup
-      @connection    = stub(:drop_database => true)
-      @configuration = {
-        'adapter'  => 'postgresql',
-        'database' => 'my-app-db'
-      }
+    class PostgreSQLDBDropTest < ActiveRecord::TestCase
+      def setup
+        @connection    = stub(drop_database: true)
+        @configuration = {
+          "adapter"  => "postgresql",
+          "database" => "my-app-db"
+        }
 
-      ActiveRecord::Base.stubs(:connection).returns(@connection)
-      ActiveRecord::Base.stubs(:establish_connection).returns(true)
+        ActiveRecord::Base.stubs(:connection).returns(@connection)
+        ActiveRecord::Base.stubs(:establish_connection).returns(true)
 
-      $stdout, @original_stdout = StringIO.new, $stdout
-      $stderr, @original_stderr = StringIO.new, $stderr
-    end
+        $stdout, @original_stdout = StringIO.new, $stdout
+        $stderr, @original_stderr = StringIO.new, $stderr
+      end
 
-    def teardown
-      $stdout, $stderr = @original_stdout, @original_stderr
-    end
+      def teardown
+        $stdout, $stderr = @original_stdout, @original_stderr
+      end
 
-    def test_establishes_connection_to_postgresql_database
-      ActiveRecord::Base.expects(:establish_connection).with(
-        'adapter'            => 'postgresql',
-        'database'           => 'postgres',
-        'schema_search_path' => 'public'
-      )
+      def test_establishes_connection_to_postgresql_database
+        ActiveRecord::Base.expects(:establish_connection).with(
+          "adapter"            => "postgresql",
+          "database"           => "postgres",
+          "schema_search_path" => "public"
+        )
 
-      ActiveRecord::Tasks::DatabaseTasks.drop @configuration
-    end
+        ActiveRecord::Tasks::DatabaseTasks.drop @configuration
+      end
 
-    def test_drops_database
-      @connection.expects(:drop_database).with('my-app-db')
+      def test_drops_database
+        @connection.expects(:drop_database).with("my-app-db")
 
-      ActiveRecord::Tasks::DatabaseTasks.drop @configuration
-    end
+        ActiveRecord::Tasks::DatabaseTasks.drop @configuration
+      end
 
-    def test_when_database_dropped_successfully_outputs_info_to_stdout
-      ActiveRecord::Tasks::DatabaseTasks.drop @configuration
+      def test_when_database_dropped_successfully_outputs_info_to_stdout
+        ActiveRecord::Tasks::DatabaseTasks.drop @configuration
 
-      assert_equal $stdout.string, "Dropped database 'my-app-db'\n"
+        assert_equal "Dropped database 'my-app-db'\n", $stdout.string
+      end
     end
-  end
 
-  class PostgreSQLPurgeTest < ActiveRecord::TestCase
-    def setup
-      @connection    = stub(:create_database => true, :drop_database => true)
-      @configuration = {
-        'adapter'  => 'postgresql',
-        'database' => 'my-app-db'
-      }
-
-      ActiveRecord::Base.stubs(:connection).returns(@connection)
-      ActiveRecord::Base.stubs(:clear_active_connections!).returns(true)
-      ActiveRecord::Base.stubs(:establish_connection).returns(true)
-    end
+    class PostgreSQLPurgeTest < ActiveRecord::TestCase
+      def setup
+        @connection    = stub(create_database: true, drop_database: true)
+        @configuration = {
+          "adapter"  => "postgresql",
+          "database" => "my-app-db"
+        }
 
-    def test_clears_active_connections
-      ActiveRecord::Base.expects(:clear_active_connections!)
+        ActiveRecord::Base.stubs(:connection).returns(@connection)
+        ActiveRecord::Base.stubs(:clear_active_connections!).returns(true)
+        ActiveRecord::Base.stubs(:establish_connection).returns(true)
+      end
 
-      ActiveRecord::Tasks::DatabaseTasks.purge @configuration
-    end
+      def test_clears_active_connections
+        ActiveRecord::Base.expects(:clear_active_connections!)
 
-    def test_establishes_connection_to_postgresql_database
-      ActiveRecord::Base.expects(:establish_connection).with(
-        'adapter'            => 'postgresql',
-        'database'           => 'postgres',
-        'schema_search_path' => 'public'
-      )
+        ActiveRecord::Tasks::DatabaseTasks.purge @configuration
+      end
 
-      ActiveRecord::Tasks::DatabaseTasks.purge @configuration
-    end
+      def test_establishes_connection_to_postgresql_database
+        ActiveRecord::Base.expects(:establish_connection).with(
+          "adapter"            => "postgresql",
+          "database"           => "postgres",
+          "schema_search_path" => "public"
+        )
 
-    def test_drops_database
-      @connection.expects(:drop_database).with('my-app-db')
+        ActiveRecord::Tasks::DatabaseTasks.purge @configuration
+      end
 
-      ActiveRecord::Tasks::DatabaseTasks.purge @configuration
-    end
+      def test_drops_database
+        @connection.expects(:drop_database).with("my-app-db")
 
-    def test_creates_database
-      @connection.expects(:create_database).
-        with('my-app-db', @configuration.merge('encoding' => 'utf8'))
+        ActiveRecord::Tasks::DatabaseTasks.purge @configuration
+      end
 
-      ActiveRecord::Tasks::DatabaseTasks.purge @configuration
-    end
+      def test_creates_database
+        @connection.expects(:create_database).
+          with("my-app-db", @configuration.merge("encoding" => "utf8"))
 
-    def test_establishes_connection
-      ActiveRecord::Base.expects(:establish_connection).with(@configuration)
+        ActiveRecord::Tasks::DatabaseTasks.purge @configuration
+      end
+
+      def test_establishes_connection
+        ActiveRecord::Base.expects(:establish_connection).with(@configuration)
 
-      ActiveRecord::Tasks::DatabaseTasks.purge @configuration
+        ActiveRecord::Tasks::DatabaseTasks.purge @configuration
+      end
     end
-  end
 
-  class PostgreSQLDBCharsetTest < ActiveRecord::TestCase
-    def setup
-      @connection    = stub(:create_database => true)
-      @configuration = {
-        'adapter'  => 'postgresql',
-        'database' => 'my-app-db'
-      }
+    class PostgreSQLDBCharsetTest < ActiveRecord::TestCase
+      def setup
+        @connection    = stub(create_database: true)
+        @configuration = {
+          "adapter"  => "postgresql",
+          "database" => "my-app-db"
+        }
 
-      ActiveRecord::Base.stubs(:connection).returns(@connection)
-      ActiveRecord::Base.stubs(:establish_connection).returns(true)
-    end
+        ActiveRecord::Base.stubs(:connection).returns(@connection)
+        ActiveRecord::Base.stubs(:establish_connection).returns(true)
+      end
 
-    def test_db_retrieves_charset
-      @connection.expects(:encoding)
-      ActiveRecord::Tasks::DatabaseTasks.charset @configuration
+      def test_db_retrieves_charset
+        @connection.expects(:encoding)
+        ActiveRecord::Tasks::DatabaseTasks.charset @configuration
+      end
     end
-  end
 
-  class PostgreSQLDBCollationTest < ActiveRecord::TestCase
-    def setup
-      @connection    = stub(:create_database => true)
-      @configuration = {
-        'adapter'  => 'postgresql',
-        'database' => 'my-app-db'
-      }
+    class PostgreSQLDBCollationTest < ActiveRecord::TestCase
+      def setup
+        @connection    = stub(create_database: true)
+        @configuration = {
+          "adapter"  => "postgresql",
+          "database" => "my-app-db"
+        }
 
-      ActiveRecord::Base.stubs(:connection).returns(@connection)
-      ActiveRecord::Base.stubs(:establish_connection).returns(true)
-    end
+        ActiveRecord::Base.stubs(:connection).returns(@connection)
+        ActiveRecord::Base.stubs(:establish_connection).returns(true)
+      end
 
-    def test_db_retrieves_collation
-      @connection.expects(:collation)
-      ActiveRecord::Tasks::DatabaseTasks.collation @configuration
+      def test_db_retrieves_collation
+        @connection.expects(:collation)
+        ActiveRecord::Tasks::DatabaseTasks.collation @configuration
+      end
     end
-  end
 
-  class PostgreSQLStructureDumpTest < ActiveRecord::TestCase
-    def setup
-      @connection    = stub(:structure_dump => true)
-      @configuration = {
-        'adapter'  => 'postgresql',
-        'database' => 'my-app-db'
-      }
-      @filename = "awesome-file.sql"
-
-      ActiveRecord::Base.stubs(:connection).returns(@connection)
-      ActiveRecord::Base.stubs(:establish_connection).returns(true)
-      Kernel.stubs(:system)
-      File.stubs(:open)
-    end
+    class PostgreSQLStructureDumpTest < ActiveRecord::TestCase
+      def setup
+        @connection    = stub(schema_search_path: nil, structure_dump: true)
+        @configuration = {
+          "adapter"  => "postgresql",
+          "database" => "my-app-db"
+        }
+        @filename = "/tmp/awesome-file.sql"
+        FileUtils.touch(@filename)
 
-    def test_structure_dump
-      Kernel.expects(:system).with('pg_dump', '-s', '-x', '-O', '-f', @filename, 'my-app-db').returns(true)
+        ActiveRecord::Base.stubs(:connection).returns(@connection)
+        ActiveRecord::Base.stubs(:establish_connection).returns(true)
+      end
 
-      ActiveRecord::Tasks::DatabaseTasks.structure_dump(@configuration, @filename)
-    end
+      def teardown
+        FileUtils.rm_f(@filename)
+      end
 
-    def test_structure_dump_with_schema_search_path
-      @configuration['schema_search_path'] = 'foo,bar'
+      def test_structure_dump
+        Kernel.expects(:system).with("pg_dump", "-s", "-x", "-O", "-f", @filename, "my-app-db").returns(true)
 
-      Kernel.expects(:system).with('pg_dump', '-s', '-x', '-O', '-f', @filename, '--schema=foo', '--schema=bar', 'my-app-db').returns(true)
+        ActiveRecord::Tasks::DatabaseTasks.structure_dump(@configuration, @filename)
+      end
 
-      ActiveRecord::Tasks::DatabaseTasks.structure_dump(@configuration, @filename)
-    end
+      def test_structure_dump_header_comments_removed
+        Kernel.stubs(:system).returns(true)
+        File.write(@filename, "-- header comment\n\n-- more header comment\n statement \n-- lower comment\n")
 
-    def test_structure_dump_with_schema_search_path_and_dump_schemas_all
-      @configuration['schema_search_path'] = 'foo,bar'
+        ActiveRecord::Tasks::DatabaseTasks.structure_dump(@configuration, @filename)
+
+        assert_equal [" statement \n", "-- lower comment\n"], File.readlines(@filename).first(2)
+      end
 
-      Kernel.expects(:system).with("pg_dump", '-s', '-x', '-O', '-f', @filename,  'my-app-db').returns(true)
+      def test_structure_dump_with_extra_flags
+        expected_command = ["pg_dump", "-s", "-x", "-O", "-f", @filename, "--noop", "my-app-db"]
+
+        assert_called_with(Kernel, :system, expected_command, returns: true) do
+          with_structure_dump_flags(["--noop"]) do
+            ActiveRecord::Tasks::DatabaseTasks.structure_dump(@configuration, @filename)
+          end
+        end
+      end
+
+      def test_structure_dump_with_ignore_tables
+        ActiveRecord::SchemaDumper.expects(:ignore_tables).returns(["foo", "bar"])
+
+        Kernel.expects(:system).with("pg_dump", "-s", "-x", "-O", "-f", @filename, "-T", "foo", "-T", "bar", "my-app-db").returns(true)
 
-      with_dump_schemas(:all) do
         ActiveRecord::Tasks::DatabaseTasks.structure_dump(@configuration, @filename)
       end
-    end
 
-    def test_structure_dump_with_dump_schemas_string
-      Kernel.expects(:system).with("pg_dump", '-s', '-x', '-O', '-f', @filename, '--schema=foo', '--schema=bar', "my-app-db").returns(true)
+      def test_structure_dump_with_schema_search_path
+        @configuration["schema_search_path"] = "foo,bar"
+
+        Kernel.expects(:system).with("pg_dump", "-s", "-x", "-O", "-f", @filename, "--schema=foo", "--schema=bar", "my-app-db").returns(true)
 
-      with_dump_schemas('foo,bar') do
         ActiveRecord::Tasks::DatabaseTasks.structure_dump(@configuration, @filename)
       end
-    end
 
-    private
+      def test_structure_dump_with_schema_search_path_and_dump_schemas_all
+        @configuration["schema_search_path"] = "foo,bar"
 
-    def with_dump_schemas(value, &block)
-      old_dump_schemas = ActiveRecord::Base.dump_schemas
-      ActiveRecord::Base.dump_schemas = value
-      yield
-    ensure
-      ActiveRecord::Base.dump_schemas = old_dump_schemas
-    end
-  end
+        Kernel.expects(:system).with("pg_dump", "-s", "-x", "-O", "-f", @filename,  "my-app-db").returns(true)
 
-  class PostgreSQLStructureLoadTest < ActiveRecord::TestCase
-    def setup
-      @connection    = stub
-      @configuration = {
-        'adapter'  => 'postgresql',
-        'database' => 'my-app-db'
-      }
-
-      ActiveRecord::Base.stubs(:connection).returns(@connection)
-      ActiveRecord::Base.stubs(:establish_connection).returns(true)
-      Kernel.stubs(:system)
-    end
+        with_dump_schemas(:all) do
+          ActiveRecord::Tasks::DatabaseTasks.structure_dump(@configuration, @filename)
+        end
+      end
 
-    def test_structure_load
-      filename = "awesome-file.sql"
-      Kernel.expects(:system).with('psql', '-v', 'ON_ERROR_STOP=1', '-q', '-f', filename, @configuration['database']).returns(true)
+      def test_structure_dump_with_dump_schemas_string
+        Kernel.expects(:system).with("pg_dump", "-s", "-x", "-O", "-f", @filename, "--schema=foo", "--schema=bar", "my-app-db").returns(true)
 
-      ActiveRecord::Tasks::DatabaseTasks.structure_load(@configuration, filename)
-    end
+        with_dump_schemas("foo,bar") do
+          ActiveRecord::Tasks::DatabaseTasks.structure_dump(@configuration, @filename)
+        end
+      end
+
+      def test_structure_dump_execution_fails
+        filename = "awesome-file.sql"
+        Kernel.expects(:system).with("pg_dump", "-s", "-x", "-O", "-f", filename, "my-app-db").returns(nil)
+
+        e = assert_raise(RuntimeError) do
+          ActiveRecord::Tasks::DatabaseTasks.structure_dump(@configuration, filename)
+        end
+        assert_match("failed to execute:", e.message)
+      end
 
-    def test_structure_load_accepts_path_with_spaces
-      filename = "awesome file.sql"
-      Kernel.expects(:system).with('psql', '-v', 'ON_ERROR_STOP=1', '-q', '-f', filename, @configuration['database']).returns(true)
+      private
+        def with_dump_schemas(value, &block)
+          old_dump_schemas = ActiveRecord::Base.dump_schemas
+          ActiveRecord::Base.dump_schemas = value
+          yield
+        ensure
+          ActiveRecord::Base.dump_schemas = old_dump_schemas
+        end
+
+        def with_structure_dump_flags(flags)
+          old = ActiveRecord::Tasks::DatabaseTasks.structure_dump_flags
+          ActiveRecord::Tasks::DatabaseTasks.structure_dump_flags = flags
+          yield
+        ensure
+          ActiveRecord::Tasks::DatabaseTasks.structure_dump_flags = old
+        end
+    end
+
+    class PostgreSQLStructureLoadTest < ActiveRecord::TestCase
+      def setup
+        @connection    = stub
+        @configuration = {
+          "adapter"  => "postgresql",
+          "database" => "my-app-db"
+        }
+
+        ActiveRecord::Base.stubs(:connection).returns(@connection)
+        ActiveRecord::Base.stubs(:establish_connection).returns(true)
+      end
+
+      def test_structure_load
+        filename = "awesome-file.sql"
+        Kernel.expects(:system).with("psql", "-v", "ON_ERROR_STOP=1", "-q", "-f", filename, @configuration["database"]).returns(true)
+
+        ActiveRecord::Tasks::DatabaseTasks.structure_load(@configuration, filename)
+      end
+
+      def test_structure_load_with_extra_flags
+        filename = "awesome-file.sql"
+        expected_command = ["psql", "-v", "ON_ERROR_STOP=1", "-q", "-f", filename, "--noop", @configuration["database"]]
 
-      ActiveRecord::Tasks::DatabaseTasks.structure_load(@configuration, filename)
+        assert_called_with(Kernel, :system, expected_command, returns: true) do
+          with_structure_load_flags(["--noop"]) do
+            ActiveRecord::Tasks::DatabaseTasks.structure_load(@configuration, filename)
+          end
+        end
+      end
+
+      def test_structure_load_accepts_path_with_spaces
+        filename = "awesome file.sql"
+        Kernel.expects(:system).with("psql", "-v", "ON_ERROR_STOP=1", "-q", "-f", filename, @configuration["database"]).returns(true)
+
+        ActiveRecord::Tasks::DatabaseTasks.structure_load(@configuration, filename)
+      end
+
+      private
+        def with_structure_load_flags(flags)
+          old = ActiveRecord::Tasks::DatabaseTasks.structure_load_flags
+          ActiveRecord::Tasks::DatabaseTasks.structure_load_flags = flags
+          yield
+        ensure
+          ActiveRecord::Tasks::DatabaseTasks.structure_load_flags = old
+        end
     end
   end
 end
-end
diff --git a/activerecord/test/cases/tasks/sqlite_rake_test.rb b/activerecord/test/cases/tasks/sqlite_rake_test.rb
index 4be03c7f61..d7e3caa2ff 100644
--- a/activerecord/test/cases/tasks/sqlite_rake_test.rb
+++ b/activerecord/test/cases/tasks/sqlite_rake_test.rb
@@ -1,220 +1,267 @@
-require 'cases/helper'
-require 'active_record/tasks/database_tasks'
-require 'pathname'
+# frozen_string_literal: true
+
+require "cases/helper"
+require "active_record/tasks/database_tasks"
+require "pathname"
 
 if current_adapter?(:SQLite3Adapter)
-module ActiveRecord
-  class SqliteDBCreateTest < ActiveRecord::TestCase
-    def setup
-      @database      = 'db_create.sqlite3'
-      @connection    = stub :connection
-      @configuration = {
-        'adapter'  => 'sqlite3',
-        'database' => @database
-      }
-
-      File.stubs(:exist?).returns(false)
-      ActiveRecord::Base.stubs(:connection).returns(@connection)
-      ActiveRecord::Base.stubs(:establish_connection).returns(true)
-
-      $stdout, @original_stdout = StringIO.new, $stdout
-      $stderr, @original_stderr = StringIO.new, $stderr
-    end
+  module ActiveRecord
+    class SqliteDBCreateTest < ActiveRecord::TestCase
+      def setup
+        @database      = "db_create.sqlite3"
+        @connection    = stub :connection
+        @configuration = {
+          "adapter"  => "sqlite3",
+          "database" => @database
+        }
+
+        File.stubs(:exist?).returns(false)
+        ActiveRecord::Base.stubs(:connection).returns(@connection)
+        ActiveRecord::Base.stubs(:establish_connection).returns(true)
+
+        $stdout, @original_stdout = StringIO.new, $stdout
+        $stderr, @original_stderr = StringIO.new, $stderr
+      end
 
-    def teardown
-      $stdout, $stderr = @original_stdout, @original_stderr
-    end
+      def teardown
+        $stdout, $stderr = @original_stdout, @original_stderr
+      end
 
-    def test_db_checks_database_exists
-      File.expects(:exist?).with(@database).returns(false)
+      def test_db_checks_database_exists
+        File.expects(:exist?).with(@database).returns(false)
 
-      ActiveRecord::Tasks::DatabaseTasks.create @configuration, '/rails/root'
-    end
+        ActiveRecord::Tasks::DatabaseTasks.create @configuration, "/rails/root"
+      end
 
-    def test_when_db_created_successfully_outputs_info_to_stdout
-      ActiveRecord::Tasks::DatabaseTasks.create @configuration, '/rails/root'
+      def test_when_db_created_successfully_outputs_info_to_stdout
+        ActiveRecord::Tasks::DatabaseTasks.create @configuration, "/rails/root"
 
-      assert_equal $stdout.string, "Created database '#{@database}'\n"
-    end
+        assert_equal "Created database '#{@database}'\n", $stdout.string
+      end
 
-    def test_db_create_when_file_exists
-      File.stubs(:exist?).returns(true)
+      def test_db_create_when_file_exists
+        File.stubs(:exist?).returns(true)
 
-      ActiveRecord::Tasks::DatabaseTasks.create @configuration, '/rails/root'
+        ActiveRecord::Tasks::DatabaseTasks.create @configuration, "/rails/root"
 
-      assert_equal $stderr.string, "Database '#{@database}' already exists\n"
-    end
+        assert_equal "Database '#{@database}' already exists\n", $stderr.string
+      end
 
-    def test_db_create_with_file_does_nothing
-      File.stubs(:exist?).returns(true)
-      $stderr.stubs(:puts).returns(nil)
+      def test_db_create_with_file_does_nothing
+        File.stubs(:exist?).returns(true)
+        $stderr.stubs(:puts).returns(nil)
 
-      ActiveRecord::Base.expects(:establish_connection).never
+        ActiveRecord::Base.expects(:establish_connection).never
 
-      ActiveRecord::Tasks::DatabaseTasks.create @configuration, '/rails/root'
-    end
+        ActiveRecord::Tasks::DatabaseTasks.create @configuration, "/rails/root"
+      end
 
-    def test_db_create_establishes_a_connection
-      ActiveRecord::Base.expects(:establish_connection).with(@configuration)
+      def test_db_create_establishes_a_connection
+        ActiveRecord::Base.expects(:establish_connection).with(@configuration)
 
-      ActiveRecord::Tasks::DatabaseTasks.create @configuration, '/rails/root'
-    end
+        ActiveRecord::Tasks::DatabaseTasks.create @configuration, "/rails/root"
+      end
 
-    def test_db_create_with_error_prints_message
-      ActiveRecord::Base.stubs(:establish_connection).raises(Exception)
+      def test_db_create_with_error_prints_message
+        ActiveRecord::Base.stubs(:establish_connection).raises(Exception)
 
-      $stderr.stubs(:puts).returns(true)
-      $stderr.expects(:puts).
-        with("Couldn't create database for #{@configuration.inspect}")
+        $stderr.stubs(:puts).returns(true)
+        $stderr.expects(:puts).
+          with("Couldn't create database for #{@configuration.inspect}")
 
-      assert_raises(Exception) { ActiveRecord::Tasks::DatabaseTasks.create @configuration, '/rails/root' }
+        assert_raises(Exception) { ActiveRecord::Tasks::DatabaseTasks.create @configuration, "/rails/root" }
+      end
     end
-  end
 
-  class SqliteDBDropTest < ActiveRecord::TestCase
-    def setup
-      @database      = "db_create.sqlite3"
-      @path          = stub(:to_s => '/absolute/path', :absolute? => true)
-      @configuration = {
-        'adapter'  => 'sqlite3',
-        'database' => @database
-      }
-
-      Pathname.stubs(:new).returns(@path)
-      File.stubs(:join).returns('/former/relative/path')
-      FileUtils.stubs(:rm).returns(true)
-
-      $stdout, @original_stdout = StringIO.new, $stdout
-      $stderr, @original_stderr = StringIO.new, $stderr
-    end
+    class SqliteDBDropTest < ActiveRecord::TestCase
+      def setup
+        @database      = "db_create.sqlite3"
+        @path          = stub(to_s: "/absolute/path", absolute?: true)
+        @configuration = {
+          "adapter"  => "sqlite3",
+          "database" => @database
+        }
+
+        Pathname.stubs(:new).returns(@path)
+        File.stubs(:join).returns("/former/relative/path")
+        FileUtils.stubs(:rm).returns(true)
+
+        $stdout, @original_stdout = StringIO.new, $stdout
+        $stderr, @original_stderr = StringIO.new, $stderr
+      end
 
-    def teardown
-      $stdout, $stderr = @original_stdout, @original_stderr
-    end
+      def teardown
+        $stdout, $stderr = @original_stdout, @original_stderr
+      end
 
-    def test_creates_path_from_database
-      Pathname.expects(:new).with(@database).returns(@path)
+      def test_creates_path_from_database
+        Pathname.expects(:new).with(@database).returns(@path)
 
-      ActiveRecord::Tasks::DatabaseTasks.drop @configuration, '/rails/root'
-    end
+        ActiveRecord::Tasks::DatabaseTasks.drop @configuration, "/rails/root"
+      end
 
-    def test_removes_file_with_absolute_path
-      File.stubs(:exist?).returns(true)
-      @path.stubs(:absolute?).returns(true)
+      def test_removes_file_with_absolute_path
+        File.stubs(:exist?).returns(true)
+        @path.stubs(:absolute?).returns(true)
 
-      FileUtils.expects(:rm).with('/absolute/path')
+        FileUtils.expects(:rm).with("/absolute/path")
 
-      ActiveRecord::Tasks::DatabaseTasks.drop @configuration, '/rails/root'
-    end
+        ActiveRecord::Tasks::DatabaseTasks.drop @configuration, "/rails/root"
+      end
 
-    def test_generates_absolute_path_with_given_root
-      @path.stubs(:absolute?).returns(false)
+      def test_generates_absolute_path_with_given_root
+        @path.stubs(:absolute?).returns(false)
 
-      File.expects(:join).with('/rails/root', @path).
-        returns('/former/relative/path')
+        File.expects(:join).with("/rails/root", @path).
+          returns("/former/relative/path")
 
-      ActiveRecord::Tasks::DatabaseTasks.drop @configuration, '/rails/root'
-    end
+        ActiveRecord::Tasks::DatabaseTasks.drop @configuration, "/rails/root"
+      end
 
-    def test_removes_file_with_relative_path
-      File.stubs(:exist?).returns(true)
-      @path.stubs(:absolute?).returns(false)
+      def test_removes_file_with_relative_path
+        File.stubs(:exist?).returns(true)
+        @path.stubs(:absolute?).returns(false)
 
-      FileUtils.expects(:rm).with('/former/relative/path')
+        FileUtils.expects(:rm).with("/former/relative/path")
 
-      ActiveRecord::Tasks::DatabaseTasks.drop @configuration, '/rails/root'
-    end
+        ActiveRecord::Tasks::DatabaseTasks.drop @configuration, "/rails/root"
+      end
 
-    def test_when_db_dropped_successfully_outputs_info_to_stdout
-      ActiveRecord::Tasks::DatabaseTasks.drop @configuration, '/rails/root'
+      def test_when_db_dropped_successfully_outputs_info_to_stdout
+        ActiveRecord::Tasks::DatabaseTasks.drop @configuration, "/rails/root"
 
-      assert_equal $stdout.string, "Dropped database '#{@database}'\n"
+        assert_equal "Dropped database '#{@database}'\n", $stdout.string
+      end
     end
-  end
 
-  class SqliteDBCharsetTest < ActiveRecord::TestCase
-    def setup
-      @database      = 'db_create.sqlite3'
-      @connection    = stub :connection
-      @configuration = {
-        'adapter'  => 'sqlite3',
-        'database' => @database
-      }
-
-      File.stubs(:exist?).returns(false)
-      ActiveRecord::Base.stubs(:connection).returns(@connection)
-      ActiveRecord::Base.stubs(:establish_connection).returns(true)
-    end
+    class SqliteDBCharsetTest < ActiveRecord::TestCase
+      def setup
+        @database      = "db_create.sqlite3"
+        @connection    = stub :connection
+        @configuration = {
+          "adapter"  => "sqlite3",
+          "database" => @database
+        }
+
+        File.stubs(:exist?).returns(false)
+        ActiveRecord::Base.stubs(:connection).returns(@connection)
+        ActiveRecord::Base.stubs(:establish_connection).returns(true)
+      end
 
-    def test_db_retrieves_charset
-      @connection.expects(:encoding)
-      ActiveRecord::Tasks::DatabaseTasks.charset @configuration, '/rails/root'
+      def test_db_retrieves_charset
+        @connection.expects(:encoding)
+        ActiveRecord::Tasks::DatabaseTasks.charset @configuration, "/rails/root"
+      end
     end
-  end
 
-  class SqliteDBCollationTest < ActiveRecord::TestCase
-    def setup
-      @database      = 'db_create.sqlite3'
-      @connection    = stub :connection
-      @configuration = {
-        'adapter'  => 'sqlite3',
-        'database' => @database
-      }
-
-      File.stubs(:exist?).returns(false)
-      ActiveRecord::Base.stubs(:connection).returns(@connection)
-      ActiveRecord::Base.stubs(:establish_connection).returns(true)
-    end
+    class SqliteDBCollationTest < ActiveRecord::TestCase
+      def setup
+        @database      = "db_create.sqlite3"
+        @connection    = stub :connection
+        @configuration = {
+          "adapter"  => "sqlite3",
+          "database" => @database
+        }
+
+        File.stubs(:exist?).returns(false)
+        ActiveRecord::Base.stubs(:connection).returns(@connection)
+        ActiveRecord::Base.stubs(:establish_connection).returns(true)
+      end
 
-    def test_db_retrieves_collation
-      assert_raise NoMethodError do
-        ActiveRecord::Tasks::DatabaseTasks.collation @configuration, '/rails/root'
+      def test_db_retrieves_collation
+        assert_raise NoMethodError do
+          ActiveRecord::Tasks::DatabaseTasks.collation @configuration, "/rails/root"
+        end
       end
     end
-  end
 
-  class SqliteStructureDumpTest < ActiveRecord::TestCase
-    def setup
-      @database      = "db_create.sqlite3"
-      @configuration = {
-        'adapter'  => 'sqlite3',
-        'database' => @database
-      }
-    end
+    class SqliteStructureDumpTest < ActiveRecord::TestCase
+      def setup
+        @database      = "db_create.sqlite3"
+        @configuration = {
+          "adapter"  => "sqlite3",
+          "database" => @database
+        }
 
-    def test_structure_dump
-      dbfile   = @database
-      filename = "awesome-file.sql"
+        `sqlite3 #{@database} 'CREATE TABLE bar(id INTEGER)'`
+        `sqlite3 #{@database} 'CREATE TABLE foo(id INTEGER)'`
+      end
 
-      ActiveRecord::Tasks::DatabaseTasks.structure_dump @configuration, filename, '/rails/root'
-      assert File.exist?(dbfile)
-      assert File.exist?(filename)
-    ensure
-      FileUtils.rm_f(filename)
-      FileUtils.rm_f(dbfile)
-    end
-  end
+      def test_structure_dump
+        dbfile   = @database
+        filename = "awesome-file.sql"
+
+        ActiveRecord::Tasks::DatabaseTasks.structure_dump @configuration, filename, "/rails/root"
+        assert File.exist?(dbfile)
+        assert File.exist?(filename)
+        assert_match(/CREATE TABLE foo/, File.read(filename))
+        assert_match(/CREATE TABLE bar/, File.read(filename))
+      ensure
+        FileUtils.rm_f(filename)
+        FileUtils.rm_f(dbfile)
+      end
+
+      def test_structure_dump_with_ignore_tables
+        dbfile   = @database
+        filename = "awesome-file.sql"
+        ActiveRecord::SchemaDumper.expects(:ignore_tables).returns(["foo"])
+
+        ActiveRecord::Tasks::DatabaseTasks.structure_dump(@configuration, filename, "/rails/root")
+        assert File.exist?(dbfile)
+        assert File.exist?(filename)
+        assert_match(/bar/, File.read(filename))
+        assert_no_match(/foo/, File.read(filename))
+      ensure
+        FileUtils.rm_f(filename)
+        FileUtils.rm_f(dbfile)
+      end
 
-  class SqliteStructureLoadTest < ActiveRecord::TestCase
-    def setup
-      @database      = "db_create.sqlite3"
-      @configuration = {
-        'adapter'  => 'sqlite3',
-        'database' => @database
-      }
+      def test_structure_dump_execution_fails
+        dbfile   = @database
+        filename = "awesome-file.sql"
+        Kernel.expects(:system).with("sqlite3", "--noop", "db_create.sqlite3", ".schema", out: "awesome-file.sql").returns(nil)
+
+        e = assert_raise(RuntimeError) do
+          with_structure_dump_flags(["--noop"]) do
+            quietly { ActiveRecord::Tasks::DatabaseTasks.structure_dump(@configuration, filename, "/rails/root") }
+          end
+        end
+        assert_match("failed to execute:", e.message)
+      ensure
+        FileUtils.rm_f(filename)
+        FileUtils.rm_f(dbfile)
+      end
+
+      private
+        def with_structure_dump_flags(flags)
+          old = ActiveRecord::Tasks::DatabaseTasks.structure_dump_flags
+          ActiveRecord::Tasks::DatabaseTasks.structure_dump_flags = flags
+          yield
+        ensure
+          ActiveRecord::Tasks::DatabaseTasks.structure_dump_flags = old
+        end
     end
 
-    def test_structure_load
-      dbfile   = @database
-      filename = "awesome-file.sql"
+    class SqliteStructureLoadTest < ActiveRecord::TestCase
+      def setup
+        @database      = "db_create.sqlite3"
+        @configuration = {
+          "adapter"  => "sqlite3",
+          "database" => @database
+        }
+      end
+
+      def test_structure_load
+        dbfile   = @database
+        filename = "awesome-file.sql"
 
-      open(filename, 'w') { |f| f.puts("select datetime('now', 'localtime');") }
-      ActiveRecord::Tasks::DatabaseTasks.structure_load @configuration, filename, '/rails/root'
-      assert File.exist?(dbfile)
-    ensure
-      FileUtils.rm_f(filename)
-      FileUtils.rm_f(dbfile)
+        open(filename, "w") { |f| f.puts("select datetime('now', 'localtime');") }
+        ActiveRecord::Tasks::DatabaseTasks.structure_load @configuration, filename, "/rails/root"
+        assert File.exist?(dbfile)
+      ensure
+        FileUtils.rm_f(filename)
+        FileUtils.rm_f(dbfile)
+      end
     end
   end
 end
-end
diff --git a/activerecord/test/cases/test_case.rb b/activerecord/test/cases/test_case.rb
index c8adc21bbc..d8c96316ed 100644
--- a/activerecord/test/cases/test_case.rb
+++ b/activerecord/test/cases/test_case.rb
@@ -1,12 +1,30 @@
-require 'active_support/test_case'
-require 'active_support/testing/stream'
+# frozen_string_literal: true
+
+require "active_support/test_case"
+require "active_support/testing/autorun"
+require "active_support/testing/method_call_assertions"
+require "active_support/testing/stream"
+require "active_record/fixtures"
+
+require "cases/validations_repair_helper"
 
 module ActiveRecord
   # = Active Record Test Case
   #
   # Defines some test assertions to test against SQL queries.
   class TestCase < ActiveSupport::TestCase #:nodoc:
+    include ActiveSupport::Testing::MethodCallAssertions
     include ActiveSupport::Testing::Stream
+    include ActiveRecord::TestFixtures
+    include ActiveRecord::ValidationsRepairHelper
+
+    self.fixture_path = FIXTURES_ROOT
+    self.use_instantiated_fixtures = false
+    self.use_transactional_tests = true
+
+    def create_fixtures(*fixture_set_names, &block)
+      ActiveRecord::FixtureSet.create_fixtures(ActiveRecord::TestCase.fixture_path, fixture_set_names, fixture_class_names, &block)
+    end
 
     def teardown
       SQLCounter.clear_log
@@ -23,7 +41,7 @@ module ActiveRecord
     ensure
       failed_patterns = []
       patterns_to_match.each do |pattern|
-        failed_patterns << pattern unless SQLCounter.log_all.any?{ |sql| pattern === sql }
+        failed_patterns << pattern unless SQLCounter.log_all.any? { |sql| pattern === sql }
       end
       assert failed_patterns.empty?, "Query pattern(s) #{failed_patterns.map(&:inspect).join(', ')} not found.#{SQLCounter.log.size == 0 ? '' : "\nQueries:\n#{SQLCounter.log.join("\n")}"}"
     end
@@ -47,11 +65,11 @@ module ActiveRecord
       assert_queries(0, options, &block)
     end
 
-    def assert_column(model, column_name, msg=nil)
+    def assert_column(model, column_name, msg = nil)
       assert has_column?(model, column_name), msg
     end
 
-    def assert_no_column(model, column_name, msg=nil)
+    def assert_no_column(model, column_name, msg = nil)
       assert_not has_column?(model, column_name), msg
     end
 
@@ -59,6 +77,10 @@ module ActiveRecord
       model.reset_column_information
       model.column_names.include?(column_name.to_s)
     end
+
+    def frozen_error_class
+      Object.const_defined?(:FrozenError) ? FrozenError : RuntimeError
+    end
   end
 
   class PostgreSQLTestCase < TestCase
@@ -85,14 +107,14 @@ module ActiveRecord
       def clear_log; self.log = []; self.log_all = []; end
     end
 
-    self.clear_log
+    clear_log
 
     self.ignored_sql = [/^PRAGMA/, /^SELECT currval/, /^SELECT CAST/, /^SELECT @@IDENTITY/, /^SELECT @@ROWCOUNT/, /^SAVEPOINT/, /^ROLLBACK TO SAVEPOINT/, /^RELEASE SAVEPOINT/, /^SHOW max_identifier_length/, /^BEGIN/, /^COMMIT/]
 
     # FIXME: this needs to be refactored so specific database can add their own
     # ignored SQL, or better yet, use a different notification for the queries
     # instead examining the SQL content.
-    oracle_ignored     = [/^select .*nextval/i, /^SAVEPOINT/, /^ROLLBACK TO/, /^\s*select .* from all_triggers/im, /^\s*select .* from all_constraints/im, /^\s*select .* from all_tab_cols/im]
+    oracle_ignored     = [/^select .*nextval/i, /^SAVEPOINT/, /^ROLLBACK TO/, /^\s*select .* from all_triggers/im, /^\s*select .* from all_constraints/im, /^\s*select .* from all_tab_cols/im, /^\s*select .* from all_sequences/im]
     mysql_ignored      = [/^SHOW FULL TABLES/i, /^SHOW FULL FIELDS/, /^SHOW CREATE TABLE /i, /^SHOW VARIABLES /, /^\s*SELECT (?:column_name|table_name)\b.*\bFROM information_schema\.(?:key_column_usage|tables)\b/im]
     postgresql_ignored = [/^\s*select\b.*\bfrom\b.*pg_namespace\b/im, /^\s*select tablename\b.*from pg_tables\b/im, /^\s*select\b.*\battname\b.*\bfrom\b.*\bpg_attribute\b/im, /^SHOW search_path/i]
     sqlite3_ignored =    [/^\s*SELECT name\b.*\bFROM sqlite_master/im, /^\s*SELECT sql\b.*\bFROM sqlite_master/im]
@@ -108,16 +130,13 @@ module ActiveRecord
     end
 
     def call(name, start, finish, message_id, values)
-      sql = values[:sql]
-
-      # FIXME: this seems bad. we should probably have a better way to indicate
-      # the query was cached
-      return if 'CACHE' == values[:name]
+      return if values[:cached]
 
+      sql = values[:sql]
       self.class.log_all << sql
-      self.class.log << sql unless ignore =~ sql
+      self.class.log << sql unless ignore.match?(sql)
     end
   end
 
-  ActiveSupport::Notifications.subscribe('sql.active_record', SQLCounter.new)
+  ActiveSupport::Notifications.subscribe("sql.active_record", SQLCounter.new)
 end
diff --git a/activerecord/test/cases/test_fixtures_test.rb b/activerecord/test/cases/test_fixtures_test.rb
index 1970fe82d0..4411410eda 100644
--- a/activerecord/test/cases/test_fixtures_test.rb
+++ b/activerecord/test/cases/test_fixtures_test.rb
@@ -1,30 +1,14 @@
-require 'cases/helper'
+# frozen_string_literal: true
+
+require "cases/helper"
 
 class TestFixturesTest < ActiveRecord::TestCase
   setup do
     @klass = Class.new
-    @klass.send(:include, ActiveRecord::TestFixtures)
-  end
-
-  def test_deprecated_use_transactional_fixtures=
-    assert_deprecated 'use use_transactional_tests= instead' do
-      @klass.use_transactional_fixtures = true
-    end
-  end
-
-  def test_use_transactional_tests_prefers_use_transactional_fixtures
-    ActiveSupport::Deprecation.silence do
-      @klass.use_transactional_fixtures = false
-    end
-
-    assert_equal false, @klass.use_transactional_tests
+    @klass.include(ActiveRecord::TestFixtures)
   end
 
   def test_use_transactional_tests_defaults_to_true
-    ActiveSupport::Deprecation.silence do
-      @klass.use_transactional_fixtures = nil
-    end
-
     assert_equal true, @klass.use_transactional_tests
   end
 
diff --git a/activerecord/test/cases/time_precision_test.rb b/activerecord/test/cases/time_precision_test.rb
index 628a8eb771..41455637bb 100644
--- a/activerecord/test/cases/time_precision_test.rb
+++ b/activerecord/test/cases/time_precision_test.rb
@@ -1,84 +1,85 @@
-require 'cases/helper'
-require 'support/schema_dumping_helper'
+# frozen_string_literal: true
 
-if subsecond_precision_supported?
-class TimePrecisionTest < ActiveRecord::TestCase
-  include SchemaDumpingHelper
-  self.use_transactional_tests = false
+require "cases/helper"
+require "support/schema_dumping_helper"
 
-  class Foo < ActiveRecord::Base; end
+if subsecond_precision_supported?
+  class TimePrecisionTest < ActiveRecord::TestCase
+    include SchemaDumpingHelper
+    self.use_transactional_tests = false
 
-  setup do
-    @connection = ActiveRecord::Base.connection
-    Foo.reset_column_information
-  end
+    class Foo < ActiveRecord::Base; end
 
-  teardown do
-    @connection.drop_table :foos, if_exists: true
-  end
+    setup do
+      @connection = ActiveRecord::Base.connection
+      Foo.reset_column_information
+    end
 
-  def test_time_data_type_with_precision
-    @connection.create_table(:foos, force: true)
-    @connection.add_column :foos, :start,  :time, precision: 3
-    @connection.add_column :foos, :finish, :time, precision: 6
-    assert_equal 3, Foo.columns_hash['start'].precision
-    assert_equal 6, Foo.columns_hash['finish'].precision
-  end
+    teardown do
+      @connection.drop_table :foos, if_exists: true
+    end
 
-  def test_passing_precision_to_time_does_not_set_limit
-    @connection.create_table(:foos, force: true) do |t|
-      t.time :start,  precision: 3
-      t.time :finish, precision: 6
+    def test_time_data_type_with_precision
+      @connection.create_table(:foos, force: true)
+      @connection.add_column :foos, :start,  :time, precision: 3
+      @connection.add_column :foos, :finish, :time, precision: 6
+      assert_equal 3, Foo.columns_hash["start"].precision
+      assert_equal 6, Foo.columns_hash["finish"].precision
     end
-    assert_nil Foo.columns_hash['start'].limit
-    assert_nil Foo.columns_hash['finish'].limit
-  end
 
-  def test_invalid_time_precision_raises_error
-    assert_raises ActiveRecord::ActiveRecordError do
+    def test_passing_precision_to_time_does_not_set_limit
       @connection.create_table(:foos, force: true) do |t|
-        t.time :start,  precision: 7
-        t.time :finish, precision: 7
+        t.time :start,  precision: 3
+        t.time :finish, precision: 6
       end
+      assert_nil Foo.columns_hash["start"].limit
+      assert_nil Foo.columns_hash["finish"].limit
     end
-  end
 
-  def test_formatting_time_according_to_precision
-    @connection.create_table(:foos, force: true) do |t|
-      t.time :start,  precision: 0
-      t.time :finish, precision: 4
+    def test_invalid_time_precision_raises_error
+      assert_raises ActiveRecord::ActiveRecordError do
+        @connection.create_table(:foos, force: true) do |t|
+          t.time :start,  precision: 7
+          t.time :finish, precision: 7
+        end
+      end
     end
-    time = ::Time.utc(2000, 1, 1, 12, 30, 0, 999999)
-    Foo.create!(start: time, finish: time)
-    assert foo = Foo.find_by(start: time)
-    assert_equal 1, Foo.where(finish: time).count
-    assert_equal time.to_s, foo.start.to_s
-    assert_equal time.to_s, foo.finish.to_s
-    assert_equal 000000, foo.start.usec
-    assert_equal 999900, foo.finish.usec
-  end
 
-  def test_schema_dump_includes_time_precision
-    @connection.create_table(:foos, force: true) do |t|
-      t.time :start,  precision: 4
-      t.time :finish, precision: 6
+    def test_formatting_time_according_to_precision
+      @connection.create_table(:foos, force: true) do |t|
+        t.time :start,  precision: 0
+        t.time :finish, precision: 4
+      end
+      time = ::Time.utc(2000, 1, 1, 12, 30, 0, 999999)
+      Foo.create!(start: time, finish: time)
+      assert foo = Foo.find_by(start: time)
+      assert_equal 1, Foo.where(finish: time).count
+      assert_equal time.to_s, foo.start.to_s
+      assert_equal time.to_s, foo.finish.to_s
+      assert_equal 000000, foo.start.usec
+      assert_equal 999900, foo.finish.usec
     end
-    output = dump_table_schema("foos")
-    assert_match %r{t\.time\s+"start",\s+precision: 4$}, output
-    assert_match %r{t\.time\s+"finish",\s+precision: 6$}, output
-  end
 
-  if current_adapter?(:PostgreSQLAdapter)
-    def test_time_precision_with_zero_should_be_dumped
+    def test_schema_dump_includes_time_precision
       @connection.create_table(:foos, force: true) do |t|
-        t.time :start,  precision: 0
-        t.time :finish, precision: 0
+        t.time :start,  precision: 4
+        t.time :finish, precision: 6
       end
       output = dump_table_schema("foos")
-      assert_match %r{t\.time\s+"start",\s+precision: 0$}, output
-      assert_match %r{t\.time\s+"finish",\s+precision: 0$}, output
+      assert_match %r{t\.time\s+"start",\s+precision: 4$}, output
+      assert_match %r{t\.time\s+"finish",\s+precision: 6$}, output
     end
-  end
 
-end
+    if current_adapter?(:PostgreSQLAdapter, :SQLServerAdapter)
+      def test_time_precision_with_zero_should_be_dumped
+        @connection.create_table(:foos, force: true) do |t|
+          t.time :start,  precision: 0
+          t.time :finish, precision: 0
+        end
+        output = dump_table_schema("foos")
+        assert_match %r{t\.time\s+"start",\s+precision: 0$}, output
+        assert_match %r{t\.time\s+"finish",\s+precision: 0$}, output
+      end
+    end
+  end
 end
diff --git a/activerecord/test/cases/timestamp_test.rb b/activerecord/test/cases/timestamp_test.rb
index 937b84bccc..54e3f47e16 100644
--- a/activerecord/test/cases/timestamp_test.rb
+++ b/activerecord/test/cases/timestamp_test.rb
@@ -1,12 +1,14 @@
-require 'cases/helper'
-require 'support/ddl_helper'
-require 'models/developer'
-require 'models/computer'
-require 'models/owner'
-require 'models/pet'
-require 'models/toy'
-require 'models/car'
-require 'models/task'
+# frozen_string_literal: true
+
+require "cases/helper"
+require "support/ddl_helper"
+require "models/developer"
+require "models/computer"
+require "models/owner"
+require "models/pet"
+require "models/toy"
+require "models/car"
+require "models/task"
 
 class TimestampTest < ActiveRecord::TestCase
   fixtures :developers, :owners, :pets, :toys, :cars, :tasks
@@ -38,8 +40,8 @@ class TimestampTest < ActiveRecord::TestCase
 
     assert_not_equal @previously_updated_at, @developer.updated_at
     assert_equal previous_salary + 10000, @developer.salary
-    assert @developer.salary_changed?, 'developer salary should have changed'
-    assert @developer.changed?, 'developer should be marked as changed'
+    assert @developer.salary_changed?, "developer salary should have changed"
+    assert @developer.changed?, "developer should be marked as changed"
     @developer.reload
     assert_equal previous_salary, @developer.salary
   end
@@ -74,12 +76,12 @@ class TimestampTest < ActiveRecord::TestCase
   end
 
   def test_touching_updates_timestamp_with_given_time
-    previously_updated_at = @developer.updated_at 
-    new_time = Time.utc(2015, 2, 16, 0, 0, 0) 
-    @developer.touch(time: new_time) 
+    previously_updated_at = @developer.updated_at
+    new_time = Time.utc(2015, 2, 16, 0, 0, 0)
+    @developer.touch(time: new_time)
 
-    assert_not_equal previously_updated_at, @developer.updated_at 
-    assert_equal new_time, @developer.updated_at 
+    assert_not_equal previously_updated_at, @developer.updated_at
+    assert_equal new_time, @developer.updated_at
   end
 
   def test_touching_an_attribute_updates_timestamp
@@ -88,8 +90,8 @@ class TimestampTest < ActiveRecord::TestCase
       @developer.touch(:created_at)
     end
 
-    assert !@developer.created_at_changed? , 'created_at should not be changed'
-    assert !@developer.changed?, 'record should not be changed'
+    assert !@developer.created_at_changed?, "created_at should not be changed"
+    assert !@developer.changed?, "record should not be changed"
     assert_not_equal previously_created_at, @developer.created_at
     assert_not_equal @previously_updated_at, @developer.updated_at
   end
@@ -106,9 +108,9 @@ class TimestampTest < ActiveRecord::TestCase
   end
 
   def test_touching_an_attribute_updates_timestamp_with_given_time
-    previously_updated_at = @developer.updated_at 
+    previously_updated_at = @developer.updated_at
     previously_created_at = @developer.created_at
-    new_time = Time.utc(2015, 2, 16, 4, 54, 0) 
+    new_time = Time.utc(2015, 2, 16, 4, 54, 0)
     @developer.touch(:created_at, time: new_time)
 
     assert_not_equal previously_created_at, @developer.created_at
@@ -228,7 +230,7 @@ class TimestampTest < ActiveRecord::TestCase
 
   def test_saving_a_new_record_belonging_to_invalid_parent_with_touch_should_not_raise_exception
     klass = Class.new(Owner) do
-      def self.name; 'Owner'; end
+      def self.name; "Owner"; end
       validate { errors.add(:base, :invalid) }
     end
 
@@ -240,8 +242,8 @@ class TimestampTest < ActiveRecord::TestCase
 
   def test_saving_a_record_with_a_belongs_to_that_specifies_touching_a_specific_attribute_the_parent_should_update_that_attribute
     klass = Class.new(ActiveRecord::Base) do
-      def self.name; 'Pet'; end
-      belongs_to :owner, :touch => :happy_at
+      def self.name; "Pet"; end
+      belongs_to :owner, touch: :happy_at
     end
 
     pet   = klass.first
@@ -256,8 +258,8 @@ class TimestampTest < ActiveRecord::TestCase
 
   def test_touching_a_record_with_a_belongs_to_that_uses_a_counter_cache_should_update_the_parent
     klass = Class.new(ActiveRecord::Base) do
-      def self.name; 'Pet'; end
-      belongs_to :owner, :counter_cache => :use_count, :touch => true
+      def self.name; "Pet"; end
+      belongs_to :owner, counter_cache: :use_count, touch: true
     end
 
     pet = klass.first
@@ -275,8 +277,8 @@ class TimestampTest < ActiveRecord::TestCase
 
   def test_touching_a_record_touches_parent_record_and_grandparent_record
     klass = Class.new(ActiveRecord::Base) do
-      def self.name; 'Toy'; end
-      belongs_to :pet, :touch => true
+      def self.name; "Toy"; end
+      belongs_to :pet, touch: true
     end
 
     toy = klass.first
@@ -293,12 +295,12 @@ class TimestampTest < ActiveRecord::TestCase
 
   def test_touching_a_record_touches_polymorphic_record
     klass = Class.new(ActiveRecord::Base) do
-      def self.name; 'Toy'; end
+      def self.name; "Toy"; end
     end
 
     wheel_klass = Class.new(ActiveRecord::Base) do
-      def self.name; 'Wheel'; end
-      belongs_to :wheelable, :polymorphic => true, :touch => true
+      def self.name; "Wheel"; end
+      belongs_to :wheelable, polymorphic: true, touch: true
     end
 
     toy = klass.first
@@ -315,7 +317,7 @@ class TimestampTest < ActiveRecord::TestCase
 
   def test_changing_parent_of_a_record_touches_both_new_and_old_parent_record
     klass = Class.new(ActiveRecord::Base) do
-      def self.name; 'Toy'; end
+      def self.name; "Toy"; end
       belongs_to :pet, touch: true
     end
 
@@ -341,12 +343,12 @@ class TimestampTest < ActiveRecord::TestCase
 
   def test_changing_parent_of_a_record_touches_both_new_and_old_polymorphic_parent_record_changes_within_same_class
     car_class = Class.new(ActiveRecord::Base) do
-      def self.name; 'Car'; end
+      def self.name; "Car"; end
     end
 
     wheel_class = Class.new(ActiveRecord::Base) do
-      def self.name; 'Wheel'; end
-      belongs_to :wheelable, :polymorphic => true, :touch => true
+      def self.name; "Wheel"; end
+      belongs_to :wheelable, polymorphic: true, touch: true
     end
 
     car1 = car_class.find(1)
@@ -368,16 +370,16 @@ class TimestampTest < ActiveRecord::TestCase
 
   def test_changing_parent_of_a_record_touches_both_new_and_old_polymorphic_parent_record_changes_with_other_class
     car_class = Class.new(ActiveRecord::Base) do
-      def self.name; 'Car'; end
+      def self.name; "Car"; end
     end
 
     toy_class = Class.new(ActiveRecord::Base) do
-      def self.name; 'Toy'; end
+      def self.name; "Toy"; end
     end
 
     wheel_class = Class.new(ActiveRecord::Base) do
-      def self.name; 'Wheel'; end
-      belongs_to :wheelable, :polymorphic => true, :touch => true
+      def self.name; "Wheel"; end
+      belongs_to :wheelable, polymorphic: true, touch: true
     end
 
     car = car_class.find(1)
@@ -399,7 +401,7 @@ class TimestampTest < ActiveRecord::TestCase
 
   def test_clearing_association_touches_the_old_record
     klass = Class.new(ActiveRecord::Base) do
-      def self.name; 'Toy'; end
+      def self.name; "Toy"; end
       belongs_to :pet, touch: true
     end
 
@@ -419,56 +421,30 @@ class TimestampTest < ActiveRecord::TestCase
 
   def test_timestamp_column_values_are_present_in_the_callbacks
     klass = Class.new(ActiveRecord::Base) do
-      self.table_name = 'people'
+      self.table_name = "people"
 
       before_create do
-        self.born_at = self.created_at
+        self.born_at = created_at
       end
     end
 
-    person = klass.create first_name: 'David'
+    person = klass.create first_name: "David"
     assert_not_equal person.born_at, nil
   end
 
-  def test_timestamp_attributes_for_create
-    toy = Toy.first
-    assert_equal [:created_at, :created_on], toy.send(:timestamp_attributes_for_create)
-  end
-
-  def test_timestamp_attributes_for_update
-    toy = Toy.first
-    assert_equal [:updated_at, :updated_on], toy.send(:timestamp_attributes_for_update)
-  end
-
-  def test_all_timestamp_attributes
-    toy = Toy.first
-    assert_equal [:created_at, :created_on, :updated_at, :updated_on], toy.send(:all_timestamp_attributes)
-  end
-
   def test_timestamp_attributes_for_create_in_model
     toy = Toy.first
-    assert_equal [:created_at], toy.send(:timestamp_attributes_for_create_in_model)
+    assert_equal ["created_at"], toy.send(:timestamp_attributes_for_create_in_model)
   end
 
   def test_timestamp_attributes_for_update_in_model
     toy = Toy.first
-    assert_equal [:updated_at], toy.send(:timestamp_attributes_for_update_in_model)
+    assert_equal ["updated_at"], toy.send(:timestamp_attributes_for_update_in_model)
   end
 
   def test_all_timestamp_attributes_in_model
     toy = Toy.first
-    assert_equal [:created_at, :updated_at], toy.send(:all_timestamp_attributes_in_model)
-  end
-
-  def test_index_is_created_for_both_timestamps
-    ActiveRecord::Base.connection.create_table(:foos, force: true) do |t|
-      t.timestamps(:foos, null: true, index: true)
-    end
-
-    indexes = ActiveRecord::Base.connection.indexes('foos')
-    assert_equal ['created_at', 'updated_at'], indexes.flat_map(&:columns).sort
-  ensure
-    ActiveRecord::Base.connection.drop_table(:foos)
+    assert_equal ["created_at", "updated_at"], toy.send(:all_timestamp_attributes_in_model)
   end
 end
 
@@ -488,4 +464,15 @@ class TimestampsWithoutTransactionTest < ActiveRecord::TestCase
       assert_nil post.updated_at
     end
   end
+
+  def test_index_is_created_for_both_timestamps
+    ActiveRecord::Base.connection.create_table(:foos, force: true) do |t|
+      t.timestamps null: true, index: true
+    end
+
+    indexes = ActiveRecord::Base.connection.indexes("foos")
+    assert_equal ["created_at", "updated_at"], indexes.flat_map(&:columns).sort
+  ensure
+    ActiveRecord::Base.connection.drop_table(:foos)
+  end
 end
diff --git a/activerecord/test/cases/touch_later_test.rb b/activerecord/test/cases/touch_later_test.rb
index b47769eed7..1757031371 100644
--- a/activerecord/test/cases/touch_later_test.rb
+++ b/activerecord/test/cases/touch_later_test.rb
@@ -1,9 +1,11 @@
-require 'cases/helper'
-require 'models/invoice'
-require 'models/line_item'
-require 'models/topic'
-require 'models/node'
-require 'models/tree'
+# frozen_string_literal: true
+
+require "cases/helper"
+require "models/invoice"
+require "models/line_item"
+require "models/topic"
+require "models/node"
+require "models/tree"
 
 class TouchLaterTest < ActiveRecord::TestCase
   fixtures :nodes, :trees
@@ -24,6 +26,15 @@ class TouchLaterTest < ActiveRecord::TestCase
     assert_not invoice.changed?
   end
 
+  def test_touch_later_respects_no_touching_policy
+    time = Time.now.utc - 25.days
+    topic = Topic.create!(updated_at: time, created_at: time)
+    Topic.no_touching do
+      topic.touch_later
+    end
+    assert_equal time.to_i, topic.updated_at.to_i
+  end
+
   def test_touch_later_update_the_attributes
     time = Time.now.utc - 25.days
     topic = Topic.create!(updated_at: time, created_at: time)
diff --git a/activerecord/test/cases/transaction_callbacks_test.rb b/activerecord/test/cases/transaction_callbacks_test.rb
index 8a7f19293d..1f370a80ee 100644
--- a/activerecord/test/cases/transaction_callbacks_test.rb
+++ b/activerecord/test/cases/transaction_callbacks_test.rb
@@ -1,7 +1,9 @@
+# frozen_string_literal: true
+
 require "cases/helper"
-require 'models/owner'
-require 'models/pet'
-require 'models/topic'
+require "models/owner"
+require "models/pet"
+require "models/topic"
 
 class TransactionCallbacksTest < ActiveRecord::TestCase
   fixtures :topics, :owners, :pets
@@ -17,7 +19,7 @@ class TransactionCallbacksTest < ActiveRecord::TestCase
 
     attr_accessor :save_on_after_create
     after_create do
-      self.save! if save_on_after_create
+      save! if save_on_after_create
     end
 
     def history
@@ -68,17 +70,17 @@ class TransactionCallbacksTest < ActiveRecord::TestCase
 
     def do_before_commit(on)
       blocks = @before_commit[on] if defined?(@before_commit)
-      blocks.each{|b| b.call(self)} if blocks
+      blocks.each { |b| b.call(self) } if blocks
     end
 
     def do_after_commit(on)
       blocks = @after_commit[on] if defined?(@after_commit)
-      blocks.each{|b| b.call(self)} if blocks
+      blocks.each { |b| b.call(self) } if blocks
     end
 
     def do_after_rollback(on)
       blocks = @after_rollback[on] if defined?(@after_rollback)
-      blocks.each{|b| b.call(self)} if blocks
+      blocks.each { |b| b.call(self) } if blocks
     end
   end
 
@@ -88,7 +90,7 @@ class TransactionCallbacksTest < ActiveRecord::TestCase
 
   # FIXME: Test behavior, not implementation.
   def test_before_commit_exception_should_pop_transaction_stack
-    @first.before_commit_block { raise 'better pop this txn from the stack!' }
+    @first.before_commit_block { raise "better pop this txn from the stack!" }
 
     original_txn = @first.class.connection.current_transaction
 
@@ -101,8 +103,8 @@ class TransactionCallbacksTest < ActiveRecord::TestCase
   end
 
   def test_call_after_commit_after_transaction_commits
-    @first.after_commit_block{|r| r.history << :after_commit}
-    @first.after_rollback_block{|r| r.history << :after_rollback}
+    @first.after_commit_block { |r| r.history << :after_commit }
+    @first.after_rollback_block { |r| r.history << :after_rollback }
 
     @first.save!
     assert_equal [:after_commit], @first.history
@@ -123,7 +125,7 @@ class TransactionCallbacksTest < ActiveRecord::TestCase
   end
 
   def test_only_call_after_commit_on_create_after_transaction_commits_for_new_record
-    new_record = TopicWithCallbacks.new(:title => "New topic", :written_on => Date.today)
+    new_record = TopicWithCallbacks.new(title: "New topic", written_on: Date.today)
     add_transaction_execution_blocks new_record
 
     new_record.save!
@@ -131,17 +133,17 @@ class TransactionCallbacksTest < ActiveRecord::TestCase
   end
 
   def test_only_call_after_commit_on_create_after_transaction_commits_for_new_record_if_create_succeeds_creating_through_association
-    topic = TopicWithCallbacks.create!(:title => "New topic", :written_on => Date.today)
+    topic = TopicWithCallbacks.create!(title: "New topic", written_on: Date.today)
     reply = topic.replies.create
 
     assert_equal [], reply.history
   end
 
   def test_only_call_after_commit_on_create_and_doesnt_leaky
-    r = ReplyWithCallbacks.new(content: 'foo')
+    r = ReplyWithCallbacks.new(content: "foo")
     r.save_on_after_create = true
     r.save!
-    r.content = 'bar'
+    r.content = "bar"
     r.save!
     r.save!
     assert_equal [:commit_on_create], r.history
@@ -155,7 +157,7 @@ class TransactionCallbacksTest < ActiveRecord::TestCase
   end
 
   def test_only_call_after_commit_on_top_level_transactions
-    @first.after_commit_block{|r| r.history << :after_commit}
+    @first.after_commit_block { |r| r.history << :after_commit }
     assert @first.history.empty?
 
     @first.transaction do
@@ -168,8 +170,8 @@ class TransactionCallbacksTest < ActiveRecord::TestCase
   end
 
   def test_call_after_rollback_after_transaction_rollsback
-    @first.after_commit_block{|r| r.history << :after_commit}
-    @first.after_rollback_block{|r| r.history << :after_rollback}
+    @first.after_commit_block { |r| r.history << :after_commit }
+    @first.after_rollback_block { |r| r.history << :after_rollback }
 
     Topic.transaction do
       @first.save!
@@ -213,7 +215,7 @@ class TransactionCallbacksTest < ActiveRecord::TestCase
   end
 
   def test_only_call_after_rollback_on_create_after_transaction_rollsback_for_new_record
-    new_record = TopicWithCallbacks.new(:title => "New topic", :written_on => Date.today)
+    new_record = TopicWithCallbacks.new(title: "New topic", written_on: Date.today)
     add_transaction_execution_blocks new_record
 
     Topic.transaction do
@@ -243,20 +245,20 @@ class TransactionCallbacksTest < ActiveRecord::TestCase
   end
 
   def test_only_call_after_rollback_on_records_rolled_back_to_a_savepoint
-    def @first.rollbacks(i=0); @rollbacks ||= 0; @rollbacks += i if i; end
-    def @first.commits(i=0); @commits ||= 0; @commits += i if i; end
-    @first.after_rollback_block{|r| r.rollbacks(1)}
-    @first.after_commit_block{|r| r.commits(1)}
+    def @first.rollbacks(i = 0); @rollbacks ||= 0; @rollbacks += i if i; end
+    def @first.commits(i = 0); @commits ||= 0; @commits += i if i; end
+    @first.after_rollback_block { |r| r.rollbacks(1) }
+    @first.after_commit_block { |r| r.commits(1) }
 
     second = TopicWithCallbacks.find(3)
-    def second.rollbacks(i=0); @rollbacks ||= 0; @rollbacks += i if i; end
-    def second.commits(i=0); @commits ||= 0; @commits += i if i; end
-    second.after_rollback_block{|r| r.rollbacks(1)}
-    second.after_commit_block{|r| r.commits(1)}
+    def second.rollbacks(i = 0); @rollbacks ||= 0; @rollbacks += i if i; end
+    def second.commits(i = 0); @commits ||= 0; @commits += i if i; end
+    second.after_rollback_block { |r| r.rollbacks(1) }
+    second.after_commit_block { |r| r.commits(1) }
 
     Topic.transaction do
       @first.save!
-      Topic.transaction(:requires_new => true) do
+      Topic.transaction(requires_new: true) do
         second.save!
         raise ActiveRecord::Rollback
       end
@@ -269,19 +271,19 @@ class TransactionCallbacksTest < ActiveRecord::TestCase
   end
 
   def test_only_call_after_rollback_on_records_rolled_back_to_a_savepoint_when_release_savepoint_fails
-    def @first.rollbacks(i=0); @rollbacks ||= 0; @rollbacks += i if i; end
-    def @first.commits(i=0); @commits ||= 0; @commits += i if i; end
+    def @first.rollbacks(i = 0); @rollbacks ||= 0; @rollbacks += i if i; end
+    def @first.commits(i = 0); @commits ||= 0; @commits += i if i; end
 
-    @first.after_rollback_block{|r| r.rollbacks(1)}
-    @first.after_commit_block{|r| r.commits(1)}
+    @first.after_rollback_block { |r| r.rollbacks(1) }
+    @first.after_commit_block { |r| r.commits(1) }
 
     Topic.transaction do
       @first.save
-      Topic.transaction(:requires_new => true) do
+      Topic.transaction(requires_new: true) do
         @first.save!
         raise ActiveRecord::Rollback
       end
-      Topic.transaction(:requires_new => true) do
+      Topic.transaction(requires_new: true) do
         @first.save!
         raise ActiveRecord::Rollback
       end
@@ -292,7 +294,7 @@ class TransactionCallbacksTest < ActiveRecord::TestCase
   end
 
   def test_after_commit_callback_should_not_swallow_errors
-    @first.after_commit_block{ fail "boom" }
+    @first.after_commit_block { fail "boom" }
     assert_raises(RuntimeError) do
       Topic.transaction do
         @first.save!
@@ -303,8 +305,8 @@ class TransactionCallbacksTest < ActiveRecord::TestCase
   def test_after_commit_callback_when_raise_should_not_restore_state
     first = TopicWithCallbacks.new
     second = TopicWithCallbacks.new
-    first.after_commit_block{ fail "boom" }
-    second.after_commit_block{ fail "boom" }
+    first.after_commit_block { fail "boom" }
+    second.after_commit_block { fail "boom" }
 
     begin
       Topic.transaction do
@@ -322,7 +324,7 @@ class TransactionCallbacksTest < ActiveRecord::TestCase
 
   def test_after_rollback_callback_should_not_swallow_errors_when_set_to_raise
     error_class = Class.new(StandardError)
-    @first.after_rollback_block{ raise error_class }
+    @first.after_rollback_block { raise error_class }
     assert_raises(error_class) do
       Topic.transaction do
         @first.save!
@@ -336,8 +338,8 @@ class TransactionCallbacksTest < ActiveRecord::TestCase
 
     first = TopicWithCallbacks.new
     second = TopicWithCallbacks.new
-    first.after_rollback_block{ raise error_class }
-    second.after_rollback_block{ raise error_class }
+    first.after_rollback_block { raise error_class }
+    second.after_rollback_block { raise error_class }
 
     begin
       Topic.transaction do
@@ -355,13 +357,13 @@ class TransactionCallbacksTest < ActiveRecord::TestCase
 
   def test_after_rollback_callbacks_should_validate_on_condition
     assert_raise(ArgumentError) { Topic.after_rollback(on: :save) }
-    e = assert_raise(ArgumentError) { Topic.after_rollback(on: 'create') }
+    e = assert_raise(ArgumentError) { Topic.after_rollback(on: "create") }
     assert_match(/:on conditions for after_commit and after_rollback callbacks have to be one of \[:create, :destroy, :update\]/, e.message)
   end
 
   def test_after_commit_callbacks_should_validate_on_condition
     assert_raise(ArgumentError) { Topic.after_commit(on: :save) }
-    e = assert_raise(ArgumentError) { Topic.after_commit(on: 'create') }
+    e = assert_raise(ArgumentError) { Topic.after_commit(on: "create") }
     assert_match(/:on conditions for after_commit and after_rollback callbacks have to be one of \[:create, :destroy, :update\]/, e.message)
   end
 
@@ -449,9 +451,52 @@ class CallbacksOnMultipleActionsTest < ActiveRecord::TestCase
   end
 end
 
+class CallbacksOnDestroyUpdateActionRaceTest < ActiveRecord::TestCase
+  class TopicWithHistory < ActiveRecord::Base
+    self.table_name = :topics
 
-class TransactionEnrollmentCallbacksTest < ActiveRecord::TestCase
+    def self.clear_history
+      @@history = []
+    end
+
+    def self.history
+      @@history ||= []
+    end
+  end
 
+  class TopicWithCallbacksOnDestroy < TopicWithHistory
+    after_commit(on: :destroy) { |record| record.class.history << :destroy }
+  end
+
+  class TopicWithCallbacksOnUpdate < TopicWithHistory
+    after_commit(on: :update) { |record| record.class.history << :update }
+  end
+
+  def test_trigger_once_on_multiple_deletions
+    TopicWithCallbacksOnDestroy.clear_history
+    topic = TopicWithCallbacksOnDestroy.new
+    topic.save
+    topic_clone = TopicWithCallbacksOnDestroy.find(topic.id)
+    topic.destroy
+    topic_clone.destroy
+
+    assert_equal [:destroy], TopicWithCallbacksOnDestroy.history
+  end
+
+  def test_trigger_on_update_where_row_was_deleted
+    TopicWithCallbacksOnUpdate.clear_history
+    topic = TopicWithCallbacksOnUpdate.new
+    topic.save
+    topic_clone = TopicWithCallbacksOnUpdate.find(topic.id)
+    topic.destroy
+    topic_clone.author_name = "Test Author"
+    topic_clone.save
+
+    assert_equal [], TopicWithCallbacksOnUpdate.history
+  end
+end
+
+class TransactionEnrollmentCallbacksTest < ActiveRecord::TestCase
   class TopicWithoutTransactionalEnrollmentCallbacks < ActiveRecord::Base
     self.table_name = :topics
 
@@ -470,7 +515,7 @@ class TransactionEnrollmentCallbacksTest < ActiveRecord::TestCase
 
   def test_commit_does_not_run_transactions_callbacks_without_enrollment
     @topic.transaction do
-      @topic.content = 'foo'
+      @topic.content = "foo"
       @topic.save!
     end
     assert @topic.history.empty?
@@ -479,7 +524,7 @@ class TransactionEnrollmentCallbacksTest < ActiveRecord::TestCase
   def test_commit_run_transactions_callbacks_with_explicit_enrollment
     @topic.transaction do
       2.times do
-        @topic.content = 'foo'
+        @topic.content = "foo"
         @topic.save!
       end
       @topic.class.connection.add_transaction_record(@topic)
@@ -489,7 +534,7 @@ class TransactionEnrollmentCallbacksTest < ActiveRecord::TestCase
 
   def test_rollback_does_not_run_transactions_callbacks_without_enrollment
     @topic.transaction do
-      @topic.content = 'foo'
+      @topic.content = "foo"
       @topic.save!
       raise ActiveRecord::Rollback
     end
@@ -499,7 +544,7 @@ class TransactionEnrollmentCallbacksTest < ActiveRecord::TestCase
   def test_rollback_run_transactions_callbacks_with_explicit_enrollment
     @topic.transaction do
       2.times do
-        @topic.content = 'foo'
+        @topic.content = "foo"
         @topic.save!
       end
       @topic.class.connection.add_transaction_record(@topic)
@@ -508,3 +553,43 @@ class TransactionEnrollmentCallbacksTest < ActiveRecord::TestCase
     assert_equal [:rollback], @topic.history
   end
 end
+
+class CallbacksOnActionAndConditionTest < ActiveRecord::TestCase
+  self.use_transactional_tests = false
+
+  class TopicWithCallbacksOnActionAndCondition < ActiveRecord::Base
+    self.table_name = :topics
+
+    after_commit(on: [:create, :update], if: :run_callback?) { |record| record.history << :create_or_update }
+
+    def clear_history
+      @history = []
+    end
+
+    def history
+      @history ||= []
+    end
+
+    def run_callback?
+      self.history << :run_callback?
+      true
+    end
+
+    attr_accessor :save_before_commit_history, :update_title
+  end
+
+  def test_callback_on_action_with_condition
+    topic = TopicWithCallbacksOnActionAndCondition.new
+    topic.save
+    assert_equal [:run_callback?, :create_or_update], topic.history
+
+    topic.clear_history
+    topic.approved = true
+    topic.save
+    assert_equal [:run_callback?, :create_or_update], topic.history
+
+    topic.clear_history
+    topic.destroy
+    assert_equal [], topic.history
+  end
+end
diff --git a/activerecord/test/cases/transaction_isolation_test.rb b/activerecord/test/cases/transaction_isolation_test.rb
index 2f7d208ed2..eaafd13360 100644
--- a/activerecord/test/cases/transaction_isolation_test.rb
+++ b/activerecord/test/cases/transaction_isolation_test.rb
@@ -1,4 +1,6 @@
-require 'cases/helper'
+# frozen_string_literal: true
+
+require "cases/helper"
 
 unless ActiveRecord::Base.connection.supports_transaction_isolation?
   class TransactionIsolationUnsupportedTest < ActiveRecord::TestCase
@@ -9,22 +11,20 @@ unless ActiveRecord::Base.connection.supports_transaction_isolation?
 
     test "setting the isolation level raises an error" do
       assert_raises(ActiveRecord::TransactionIsolationError) do
-        Tag.transaction(isolation: :serializable) { }
+        Tag.transaction(isolation: :serializable) {}
       end
     end
   end
-end
-
-if ActiveRecord::Base.connection.supports_transaction_isolation?
+else
   class TransactionIsolationTest < ActiveRecord::TestCase
     self.use_transactional_tests = false
 
     class Tag < ActiveRecord::Base
-      self.table_name = 'tags'
+      self.table_name = "tags"
     end
 
     class Tag2 < ActiveRecord::Base
-      self.table_name = 'tags'
+      self.table_name = "tags"
     end
 
     setup do
@@ -63,18 +63,18 @@ if ActiveRecord::Base.connection.supports_transaction_isolation?
     # We are testing that a nonrepeatable read does not happen
     if ActiveRecord::Base.connection.transaction_isolation_levels.include?(:repeatable_read)
       test "repeatable read" do
-        tag = Tag.create(name: 'jon')
+        tag = Tag.create(name: "jon")
 
         Tag.transaction(isolation: :repeatable_read) do
           tag.reload
-          Tag2.find(tag.id).update(name: 'emily')
+          Tag2.find(tag.id).update(name: "emily")
 
           tag.reload
-          assert_equal 'jon', tag.name
+          assert_equal "jon", tag.name
         end
 
         tag.reload
-        assert_equal 'emily', tag.name
+        assert_equal "emily", tag.name
       end
     end
 
@@ -90,7 +90,7 @@ if ActiveRecord::Base.connection.supports_transaction_isolation?
     test "setting isolation when joining a transaction raises an error" do
       Tag.transaction do
         assert_raises(ActiveRecord::TransactionIsolationError) do
-          Tag.transaction(isolation: :serializable) { }
+          Tag.transaction(isolation: :serializable) {}
         end
       end
     end
@@ -98,7 +98,7 @@ if ActiveRecord::Base.connection.supports_transaction_isolation?
     test "setting isolation when starting a nested transaction raises error" do
       Tag.transaction do
         assert_raises(ActiveRecord::TransactionIsolationError) do
-          Tag.transaction(requires_new: true, isolation: :serializable) { }
+          Tag.transaction(requires_new: true, isolation: :serializable) {}
         end
       end
     end
diff --git a/activerecord/test/cases/transactions_test.rb b/activerecord/test/cases/transactions_test.rb
index 791b895d02..c110fa2f7d 100644
--- a/activerecord/test/cases/transactions_test.rb
+++ b/activerecord/test/cases/transactions_test.rb
@@ -1,16 +1,18 @@
+# frozen_string_literal: true
+
 require "cases/helper"
-require 'models/topic'
-require 'models/reply'
-require 'models/developer'
-require 'models/computer'
-require 'models/book'
-require 'models/author'
-require 'models/post'
-require 'models/movie'
+require "models/topic"
+require "models/reply"
+require "models/developer"
+require "models/computer"
+require "models/book"
+require "models/author"
+require "models/post"
+require "models/movie"
 
 class TransactionTest < ActiveRecord::TestCase
   self.use_transactional_tests = false
-  fixtures :topics, :developers, :authors, :posts
+  fixtures :topics, :developers, :authors, :author_addresses, :posts
 
   def setup
     @first, @second = Topic.find(1, 2).sort_by(&:id)
@@ -98,7 +100,7 @@ class TransactionTest < ActiveRecord::TestCase
     end
 
     Topic.transaction do
-      @first.approved  = true
+      @first.approved = true
       @first.save!
     end
 
@@ -144,7 +146,7 @@ class TransactionTest < ActiveRecord::TestCase
 
   def test_raising_exception_in_callback_rollbacks_in_save
     def @first.after_save_for_transaction
-      raise 'Make the transaction rollback'
+      raise "Make the transaction rollback"
     end
 
     @first.approved = true
@@ -160,7 +162,7 @@ class TransactionTest < ActiveRecord::TestCase
     assert !@first.approved
 
     Topic.transaction do
-      @first.approved  = true
+      @first.approved = true
       @first.save!
     end
     assert !Topic.find(@first.id).approved?, "Should not commit the approved flag"
@@ -170,7 +172,7 @@ class TransactionTest < ActiveRecord::TestCase
     topic = Topic.new
 
     def topic.after_save_for_transaction
-      raise 'Make the transaction rollback'
+      raise "Make the transaction rollback"
     end
 
     assert_raises(RuntimeError) do
@@ -181,7 +183,7 @@ class TransactionTest < ActiveRecord::TestCase
   end
 
   def test_transaction_state_is_cleared_when_record_is_persisted
-    author = Author.create! name: 'foo'
+    author = Author.create! name: "foo"
     author.name = nil
     assert_not author.save
     assert_not author.new_record?
@@ -206,16 +208,6 @@ class TransactionTest < ActiveRecord::TestCase
     assert_equal posts_count, author.posts.reload.size
   end
 
-  def test_cancellation_from_returning_false_in_before_filter
-    def @first.before_save_for_transaction
-      false
-    end
-
-    assert_deprecated do
-      @first.save
-    end
-  end
-
   def test_cancellation_from_before_destroy_rollbacks_in_destroy
     add_cancelling_before_destroy_with_db_side_effect_to_topic @first
     nbooks_before_destroy = Book.count
@@ -230,7 +222,7 @@ class TransactionTest < ActiveRecord::TestCase
       send("add_cancelling_before_#{filter}_with_db_side_effect_to_topic", @first)
       nbooks_before_save = Book.count
       original_author_name = @first.author_name
-      @first.author_name += '_this_should_not_end_up_in_the_db'
+      @first.author_name += "_this_should_not_end_up_in_the_db"
       status = @first.save
       assert !status
       assert_equal original_author_name, @first.reload.author_name
@@ -241,7 +233,7 @@ class TransactionTest < ActiveRecord::TestCase
       send("add_cancelling_before_#{filter}_with_db_side_effect_to_topic", @first)
       nbooks_before_save = Book.count
       original_author_name = @first.author_name
-      @first.author_name += '_this_should_not_end_up_in_the_db'
+      @first.author_name += "_this_should_not_end_up_in_the_db"
 
       begin
         @first.save!
@@ -256,18 +248,18 @@ class TransactionTest < ActiveRecord::TestCase
   def test_callback_rollback_in_create
     topic = Class.new(Topic) {
       def after_create_for_transaction
-        raise 'Make the transaction rollback'
+        raise "Make the transaction rollback"
       end
     }
 
-    new_topic = topic.new(:title                => "A new topic",
-                          :author_name          => "Ben",
-                          :author_email_address => "ben@example.com",
-                          :written_on           => "2003-07-16t15:28:11.2233+01:00",
-                          :last_read            => "2004-04-15",
-                          :bonus_time           => "2005-01-30t15:28:00.00+01:00",
-                          :content              => "Have a nice day",
-                          :approved             => false)
+    new_topic = topic.new(title: "A new topic",
+                          author_name: "Ben",
+                          author_email_address: "ben@example.com",
+                          written_on: "2003-07-16t15:28:11.2233+01:00",
+                          last_read: "2004-04-15",
+                          bonus_time: "2005-01-30t15:28:00.00+01:00",
+                          content: "Have a nice day",
+                          approved: false)
 
     new_record_snapshot = !new_topic.persisted?
     id_present = new_topic.has_attribute?(Topic.primary_key)
@@ -279,7 +271,11 @@ class TransactionTest < ActiveRecord::TestCase
       e = assert_raises(RuntimeError) { new_topic.save }
       assert_equal "Make the transaction rollback", e.message
       assert_equal new_record_snapshot, !new_topic.persisted?, "The topic should have its old persisted value"
-      assert_equal id_snapshot, new_topic.id, "The topic should have its old id"
+      if id_snapshot.nil?
+        assert_nil new_topic.id, "The topic should have its old id"
+      else
+        assert_equal id_snapshot, new_topic.id, "The topic should have its old id"
+      end
       assert_equal id_present, new_topic.has_attribute?(Topic.primary_key)
     end
   end
@@ -291,7 +287,7 @@ class TransactionTest < ActiveRecord::TestCase
       end
     }
 
-    new_topic = topic.create(:title => "A new topic")
+    new_topic = topic.create(title: "A new topic")
     assert !new_topic.persisted?, "The topic should not be persisted"
     assert_nil new_topic.id, "The topic should not have an ID"
   end
@@ -310,6 +306,76 @@ class TransactionTest < ActiveRecord::TestCase
     assert !Topic.find(2).approved?, "Second should have been unapproved"
   end
 
+  def test_nested_transaction_with_new_transaction_applies_parent_state_on_rollback
+    topic_one = Topic.new(title: "A new topic")
+    topic_two = Topic.new(title: "Another new topic")
+
+    Topic.transaction do
+      topic_one.save
+
+      Topic.transaction(requires_new: true) do
+        topic_two.save
+
+        assert_predicate topic_one, :persisted?
+        assert_predicate topic_two, :persisted?
+      end
+
+      raise ActiveRecord::Rollback
+    end
+
+    refute_predicate topic_one, :persisted?
+    refute_predicate topic_two, :persisted?
+  end
+
+  def test_nested_transaction_without_new_transaction_applies_parent_state_on_rollback
+    topic_one = Topic.new(title: "A new topic")
+    topic_two = Topic.new(title: "Another new topic")
+
+    Topic.transaction do
+      topic_one.save
+
+      Topic.transaction do
+        topic_two.save
+
+        assert_predicate topic_one, :persisted?
+        assert_predicate topic_two, :persisted?
+      end
+
+      raise ActiveRecord::Rollback
+    end
+
+    refute_predicate topic_one, :persisted?
+    refute_predicate topic_two, :persisted?
+  end
+
+  def test_double_nested_transaction_applies_parent_state_on_rollback
+    topic_one = Topic.new(title: "A new topic")
+    topic_two = Topic.new(title: "Another new topic")
+    topic_three = Topic.new(title: "Another new topic of course")
+
+    Topic.transaction do
+      topic_one.save
+
+      Topic.transaction do
+        topic_two.save
+
+        Topic.transaction do
+          topic_three.save
+        end
+      end
+
+      assert_predicate topic_one, :persisted?
+      assert_predicate topic_two, :persisted?
+      assert_predicate topic_three, :persisted?
+
+      raise ActiveRecord::Rollback
+    end
+
+    refute_predicate topic_one, :persisted?
+    refute_predicate topic_two, :persisted?
+    refute_predicate topic_three, :persisted?
+  end
+
   def test_manually_rolling_back_a_transaction
     Topic.transaction do
       @first.approved  = true
@@ -329,7 +395,7 @@ class TransactionTest < ActiveRecord::TestCase
 
   def test_invalid_keys_for_transaction
     assert_raise ArgumentError do
-      Topic.transaction :nested => true do
+      Topic.transaction nested: true do
       end
     end
   end
@@ -342,7 +408,7 @@ class TransactionTest < ActiveRecord::TestCase
       @second.save!
 
       begin
-        Topic.transaction :requires_new => true do
+        Topic.transaction requires_new: true do
           @first.happy = false
           @first.save!
           raise
@@ -363,7 +429,7 @@ class TransactionTest < ActiveRecord::TestCase
       @second.save!
 
       begin
-        @second.transaction :requires_new => true do
+        @second.transaction requires_new: true do
           @first.happy = false
           @first.save!
           raise
@@ -403,17 +469,17 @@ class TransactionTest < ActiveRecord::TestCase
       @first.save!
 
       begin
-        Topic.transaction :requires_new => true do
+        Topic.transaction requires_new: true do
           @first.content = "Two"
           @first.save!
 
           begin
-            Topic.transaction :requires_new => true do
+            Topic.transaction requires_new: true do
               @first.content = "Three"
               @first.save!
 
               begin
-                Topic.transaction :requires_new => true do
+                Topic.transaction requires_new: true do
                   @first.content = "Four"
                   @first.save!
                   raise
@@ -443,16 +509,16 @@ class TransactionTest < ActiveRecord::TestCase
 
   def test_using_named_savepoints
     Topic.transaction do
-      @first.approved  = true
+      @first.approved = true
       @first.save!
       Topic.connection.create_savepoint("first")
 
-      @first.approved  = false
+      @first.approved = false
       @first.save!
       Topic.connection.rollback_to_savepoint("first")
       assert @first.reload.approved?
 
-      @first.approved  = false
+      @first.approved = false
       @first.save!
       Topic.connection.release_savepoint("first")
       assert_not @first.reload.approved?
@@ -493,7 +559,7 @@ class TransactionTest < ActiveRecord::TestCase
 
   def test_rollback_when_commit_raises
     assert_called(Topic.connection, :begin_db_transaction) do
-      Topic.connection.stub(:commit_db_transaction, ->{ raise('OH NOES') }) do
+      Topic.connection.stub(:commit_db_transaction, -> { raise("OH NOES") }) do
         assert_called(Topic.connection, :rollback_db_transaction) do
 
           e = assert_raise RuntimeError do
@@ -501,22 +567,23 @@ class TransactionTest < ActiveRecord::TestCase
               # do nothing
             end
           end
-          assert_equal 'OH NOES', e.message
+          assert_equal "OH NOES", e.message
         end
       end
     end
   end
 
   def test_rollback_when_saving_a_frozen_record
-    topic = Topic.new(:title => 'test')
+    topic = Topic.new(title: "test")
     topic.freeze
-    e = assert_raise(RuntimeError) { topic.save }
-    assert_match(/frozen/i, e.message) # Not good enough, but we can't do much
-                                       # about it since there is no specific error
-                                       # for frozen objects.
-    assert !topic.persisted?, 'not persisted'
+    e = assert_raise(frozen_error_class) { topic.save }
+    # Not good enough, but we can't do much
+    # about it since there is no specific error
+    # for frozen objects.
+    assert_match(/frozen/i, e.message)
+    assert !topic.persisted?, "not persisted"
     assert_nil topic.id
-    assert topic.frozen?, 'not frozen'
+    assert topic.frozen?, "not frozen"
   end
 
   def test_rollback_when_thread_killed
@@ -549,12 +616,12 @@ class TransactionTest < ActiveRecord::TestCase
 
   def test_restore_active_record_state_for_all_records_in_a_transaction
     topic_without_callbacks = Class.new(ActiveRecord::Base) do
-      self.table_name = 'topics'
+      self.table_name = "topics"
     end
 
-    topic_1 = Topic.new(:title => 'test_1')
-    topic_2 = Topic.new(:title => 'test_2')
-    topic_3 = topic_without_callbacks.new(:title => 'test_3')
+    topic_1 = Topic.new(title: "test_1")
+    topic_2 = Topic.new(title: "test_2")
+    topic_3 = topic_without_callbacks.new(title: "test_3")
 
     Topic.transaction do
       assert topic_1.save
@@ -562,27 +629,27 @@ class TransactionTest < ActiveRecord::TestCase
       assert topic_3.save
       @first.save
       @second.destroy
-      assert topic_1.persisted?, 'persisted'
+      assert topic_1.persisted?, "persisted"
       assert_not_nil topic_1.id
-      assert topic_2.persisted?, 'persisted'
+      assert topic_2.persisted?, "persisted"
       assert_not_nil topic_2.id
-      assert topic_3.persisted?, 'persisted'
+      assert topic_3.persisted?, "persisted"
       assert_not_nil topic_3.id
-      assert @first.persisted?, 'persisted'
+      assert @first.persisted?, "persisted"
       assert_not_nil @first.id
-      assert @second.destroyed?, 'destroyed'
+      assert @second.destroyed?, "destroyed"
       raise ActiveRecord::Rollback
     end
 
-    assert !topic_1.persisted?, 'not persisted'
+    assert !topic_1.persisted?, "not persisted"
     assert_nil topic_1.id
-    assert !topic_2.persisted?, 'not persisted'
+    assert !topic_2.persisted?, "not persisted"
     assert_nil topic_2.id
-    assert !topic_3.persisted?, 'not persisted'
+    assert !topic_3.persisted?, "not persisted"
     assert_nil topic_3.id
-    assert @first.persisted?, 'persisted'
+    assert @first.persisted?, "persisted"
     assert_not_nil @first.id
-    assert !@second.destroyed?, 'not destroyed'
+    assert !@second.destroyed?, "not destroyed"
   end
 
   def test_restore_frozen_state_after_double_destroy
@@ -600,13 +667,105 @@ class TransactionTest < ActiveRecord::TestCase
     assert_not topic.frozen?
   end
 
+  def test_restore_id_after_rollback
+    topic = Topic.new
+
+    Topic.transaction do
+      topic.save!
+      raise ActiveRecord::Rollback
+    end
+
+    assert_nil topic.id
+  end
+
+  def test_restore_custom_primary_key_after_rollback
+    movie = Movie.new(name: "foo")
+
+    Movie.transaction do
+      movie.save!
+      raise ActiveRecord::Rollback
+    end
+
+    assert_nil movie.movieid
+  end
+
+  def test_assign_id_after_rollback
+    topic = Topic.create!
+
+    Topic.transaction do
+      topic.save!
+      raise ActiveRecord::Rollback
+    end
+
+    topic.id = nil
+    assert_nil topic.id
+  end
+
+  def test_assign_custom_primary_key_after_rollback
+    movie = Movie.create!(name: "foo")
+
+    Movie.transaction do
+      movie.save!
+      raise ActiveRecord::Rollback
+    end
+
+    movie.movieid = nil
+    assert_nil movie.movieid
+  end
+
+  def test_read_attribute_after_rollback
+    topic = Topic.new
+
+    Topic.transaction do
+      topic.save!
+      raise ActiveRecord::Rollback
+    end
+
+    assert_nil topic.read_attribute(:id)
+  end
+
+  def test_read_attribute_with_custom_primary_key_after_rollback
+    movie = Movie.new(name: "foo")
+
+    Movie.transaction do
+      movie.save!
+      raise ActiveRecord::Rollback
+    end
+
+    assert_nil movie.read_attribute(:movieid)
+  end
+
+  def test_write_attribute_after_rollback
+    topic = Topic.create!
+
+    Topic.transaction do
+      topic.save!
+      raise ActiveRecord::Rollback
+    end
+
+    topic.write_attribute(:id, nil)
+    assert_nil topic.id
+  end
+
+  def test_write_attribute_with_custom_primary_key_after_rollback
+    movie = Movie.create!(name: "foo")
+
+    Movie.transaction do
+      movie.save!
+      raise ActiveRecord::Rollback
+    end
+
+    movie.write_attribute(:movieid, nil)
+    assert_nil movie.movieid
+  end
+
   def test_rollback_of_frozen_records
     topic = Topic.create.freeze
     Topic.transaction do
       topic.destroy
       raise ActiveRecord::Rollback
     end
-    assert topic.frozen?, 'frozen'
+    assert topic.frozen?, "frozen"
   end
 
   def test_rollback_for_freshly_persisted_records
@@ -615,7 +774,7 @@ class TransactionTest < ActiveRecord::TestCase
       topic.destroy
       raise ActiveRecord::Rollback
     end
-    assert topic.persisted?, 'persisted'
+    assert topic.persisted?, "persisted"
   end
 
   def test_sqlite_add_column_in_transaction
@@ -629,27 +788,27 @@ class TransactionTest < ActiveRecord::TestCase
 
     assert_nothing_raised do
       Topic.reset_column_information
-      Topic.connection.add_column('topics', 'stuff', :string)
-      assert Topic.column_names.include?('stuff')
+      Topic.connection.add_column("topics", "stuff", :string)
+      assert_includes Topic.column_names, "stuff"
 
       Topic.reset_column_information
-      Topic.connection.remove_column('topics', 'stuff')
-      assert !Topic.column_names.include?('stuff')
+      Topic.connection.remove_column("topics", "stuff")
+      assert_not_includes Topic.column_names, "stuff"
     end
 
     if Topic.connection.supports_ddl_transactions?
       assert_nothing_raised do
-        Topic.transaction { Topic.connection.add_column('topics', 'stuff', :string) }
+        Topic.transaction { Topic.connection.add_column("topics", "stuff", :string) }
       end
     else
       Topic.transaction do
-        assert_raise(ActiveRecord::StatementInvalid) { Topic.connection.add_column('topics', 'stuff', :string) }
+        assert_raise(ActiveRecord::StatementInvalid) { Topic.connection.add_column("topics", "stuff", :string) }
         raise ActiveRecord::Rollback
       end
     end
   ensure
     begin
-      Topic.connection.remove_column('topics', 'stuff')
+      Topic.connection.remove_column("topics", "stuff")
     rescue
     ensure
       Topic.reset_column_information
@@ -684,15 +843,53 @@ class TransactionTest < ActiveRecord::TestCase
     assert transaction.state.committed?
   end
 
+  def test_set_state_method_is_deprecated
+    connection = Topic.connection
+    transaction = ActiveRecord::ConnectionAdapters::TransactionManager.new(connection).begin_transaction
+
+    transaction.commit
+
+    assert_deprecated do
+      transaction.state.set_state(:rolledback)
+    end
+  end
+
+  def test_mark_transaction_state_as_committed
+    connection = Topic.connection
+    transaction = ActiveRecord::ConnectionAdapters::TransactionManager.new(connection).begin_transaction
+
+    transaction.rollback
+
+    assert_equal :committed, transaction.state.commit!
+  end
+
+  def test_mark_transaction_state_as_rolledback
+    connection = Topic.connection
+    transaction = ActiveRecord::ConnectionAdapters::TransactionManager.new(connection).begin_transaction
+
+    transaction.commit
+
+    assert_equal :rolledback, transaction.state.rollback!
+  end
+
+  def test_mark_transaction_state_as_nil
+    connection = Topic.connection
+    transaction = ActiveRecord::ConnectionAdapters::TransactionManager.new(connection).begin_transaction
+
+    transaction.commit
+
+    assert_nil transaction.state.nullify!
+  end
+
   def test_transaction_rollback_with_primarykeyless_tables
     connection = ActiveRecord::Base.connection
     connection.create_table(:transaction_without_primary_keys, force: true, id: false) do |t|
-       t.integer :thing_id
+      t.integer :thing_id
     end
 
     klass = Class.new(ActiveRecord::Base) do
-      self.table_name = 'transaction_without_primary_keys'
-      after_commit { } # necessary to trigger the has_transactional_callbacks branch
+      self.table_name = "transaction_without_primary_keys"
+      after_commit {} # necessary to trigger the has_transactional_callbacks branch
     end
 
     assert_no_difference(-> { klass.count }) do
@@ -702,20 +899,20 @@ class TransactionTest < ActiveRecord::TestCase
       end
     end
   ensure
-    connection.drop_table 'transaction_without_primary_keys', if_exists: true
+    connection.drop_table "transaction_without_primary_keys", if_exists: true
   end
 
   private
 
-  %w(validation save destroy).each do |filter|
-    define_method("add_cancelling_before_#{filter}_with_db_side_effect_to_topic") do |topic|
-      meta = class << topic; self; end
-      meta.send("define_method", "before_#{filter}_for_transaction") do
-        Book.create
-        throw(:abort)
+    %w(validation save destroy).each do |filter|
+      define_method("add_cancelling_before_#{filter}_with_db_side_effect_to_topic") do |topic|
+        meta = class << topic; self; end
+        meta.send("define_method", "before_#{filter}_for_transaction") do
+          Book.create
+          throw(:abort)
+        end
       end
     end
-  end
 end
 
 class TransactionsWithTransactionalFixturesTest < ActiveRecord::TestCase
@@ -757,27 +954,25 @@ class TransactionsWithTransactionalFixturesTest < ActiveRecord::TestCase
   end
 end if Topic.connection.supports_savepoints?
 
-if current_adapter?(:PostgreSQLAdapter)
+if ActiveRecord::Base.connection.supports_transaction_isolation?
   class ConcurrentTransactionTest < TransactionTest
     # This will cause transactions to overlap and fail unless they are performed on
     # separate database connections.
-    unless in_memory_db?
-      def test_transaction_per_thread
-        threads = 3.times.map do
-          Thread.new do
-            Topic.transaction do
-              topic = Topic.find(1)
-              topic.approved = !topic.approved?
-              assert topic.save!
-              topic.approved = !topic.approved?
-              assert topic.save!
-            end
-            Topic.connection.close
+    def test_transaction_per_thread
+      threads = 3.times.map do
+        Thread.new do
+          Topic.transaction do
+            topic = Topic.find(1)
+            topic.approved = !topic.approved?
+            assert topic.save!
+            topic.approved = !topic.approved?
+            assert topic.save!
           end
+          Topic.connection.close
         end
-
-        threads.each(&:join)
       end
+
+      threads.each(&:join)
     end
 
     # Test for dirty reads among simultaneous transactions.
diff --git a/activerecord/test/cases/type/adapter_specific_registry_test.rb b/activerecord/test/cases/type/adapter_specific_registry_test.rb
index 8b836b4793..b58bdd5549 100644
--- a/activerecord/test/cases/type/adapter_specific_registry_test.rb
+++ b/activerecord/test/cases/type/adapter_specific_registry_test.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require "cases/helper"
 
 module ActiveRecord
diff --git a/activerecord/test/cases/type/date_time_test.rb b/activerecord/test/cases/type/date_time_test.rb
index bc4900e1c2..c9558e25b5 100644
--- a/activerecord/test/cases/type/date_time_test.rb
+++ b/activerecord/test/cases/type/date_time_test.rb
@@ -1,9 +1,11 @@
+# frozen_string_literal: true
+
 require "cases/helper"
 require "models/task"
 
 module ActiveRecord
   module Type
-    class IntegerTest < ActiveRecord::TestCase
+    class DateTimeTest < ActiveRecord::TestCase
       def test_datetime_seconds_precision_applied_to_timestamp
         skip "This test is invalid if subsecond precision isn't supported" unless subsecond_precision_supported?
         p = Task.create!(starting: ::Time.now)
diff --git a/activerecord/test/cases/type/integer_test.rb b/activerecord/test/cases/type/integer_test.rb
index c0932d5357..15d1a675a1 100644
--- a/activerecord/test/cases/type/integer_test.rb
+++ b/activerecord/test/cases/type/integer_test.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require "cases/helper"
 require "models/company"
 
@@ -6,13 +8,13 @@ module ActiveRecord
     class IntegerTest < ActiveRecord::TestCase
       test "casting ActiveRecord models" do
         type = Type::Integer.new
-        firm = Firm.create(:name => 'Apple')
+        firm = Firm.create(name: "Apple")
         assert_nil type.cast(firm)
       end
 
       test "values which are out of range can be re-assigned" do
         klass = Class.new(ActiveRecord::Base) do
-          self.table_name = 'posts'
+          self.table_name = "posts"
           attribute :foo, :integer
         end
         model = klass.new
diff --git a/activerecord/test/cases/type/string_test.rb b/activerecord/test/cases/type/string_test.rb
index 6fe6d46711..8c51b30fdd 100644
--- a/activerecord/test/cases/type/string_test.rb
+++ b/activerecord/test/cases/type/string_test.rb
@@ -1,21 +1,23 @@
-require 'cases/helper'
+# frozen_string_literal: true
+
+require "cases/helper"
 
 module ActiveRecord
   class StringTypeTest < ActiveRecord::TestCase
     test "string mutations are detected" do
       klass = Class.new(Base)
-      klass.table_name = 'authors'
+      klass.table_name = "authors"
 
-      author = klass.create!(name: 'Sean')
+      author = klass.create!(name: "Sean")
       assert_not author.changed?
 
-      author.name << ' Griffin'
+      author.name << " Griffin"
       assert author.name_changed?
 
       author.save!
       author.reload
 
-      assert_equal 'Sean Griffin', author.name
+      assert_equal "Sean Griffin", author.name
       assert_not author.changed?
     end
   end
diff --git a/activerecord/test/cases/type/type_map_test.rb b/activerecord/test/cases/type/type_map_test.rb
index 172c6dfc4c..f3699c11a2 100644
--- a/activerecord/test/cases/type/type_map_test.rb
+++ b/activerecord/test/cases/type/type_map_test.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require "cases/helper"
 
 module ActiveRecord
@@ -15,7 +17,7 @@ module ActiveRecord
 
         mapping.register_type(/boolean/i, boolean)
 
-        assert_equal mapping.lookup('boolean'), boolean
+        assert_equal mapping.lookup("boolean"), boolean
       end
 
       def test_overriding_registered_types
@@ -26,7 +28,7 @@ module ActiveRecord
         mapping.register_type(/time/i, time)
         mapping.register_type(/time/i, timestamp)
 
-        assert_equal mapping.lookup('time'), timestamp
+        assert_equal mapping.lookup("time"), timestamp
       end
 
       def test_fuzzy_lookup
@@ -35,7 +37,7 @@ module ActiveRecord
 
         mapping.register_type(/varchar/i, string)
 
-        assert_equal mapping.lookup('varchar(20)'), string
+        assert_equal mapping.lookup("varchar(20)"), string
       end
 
       def test_aliasing_types
@@ -43,9 +45,9 @@ module ActiveRecord
         mapping = TypeMap.new
 
         mapping.register_type(/string/i, string)
-        mapping.alias_type(/varchar/i, 'string')
+        mapping.alias_type(/varchar/i, "string")
 
-        assert_equal mapping.lookup('varchar'), string
+        assert_equal mapping.lookup("varchar"), string
       end
 
       def test_changing_type_changes_aliases
@@ -54,20 +56,20 @@ module ActiveRecord
         mapping = TypeMap.new
 
         mapping.register_type(/timestamp/i, time)
-        mapping.alias_type(/datetime/i, 'timestamp')
+        mapping.alias_type(/datetime/i, "timestamp")
         mapping.register_type(/timestamp/i, timestamp)
 
-        assert_equal mapping.lookup('datetime'), timestamp
+        assert_equal mapping.lookup("datetime"), timestamp
       end
 
       def test_aliases_keep_metadata
         mapping = TypeMap.new
 
         mapping.register_type(/decimal/i) { |sql_type| sql_type }
-        mapping.alias_type(/number/i, 'decimal')
+        mapping.alias_type(/number/i, "decimal")
 
-        assert_equal mapping.lookup('number(20)'), 'decimal(20)'
-        assert_equal mapping.lookup('number'), 'decimal'
+        assert_equal mapping.lookup("number(20)"), "decimal(20)"
+        assert_equal mapping.lookup("number"), "decimal"
       end
 
       def test_register_proc
@@ -76,15 +78,15 @@ module ActiveRecord
         mapping = TypeMap.new
 
         mapping.register_type(/varchar/i) do |type|
-          if type.include?('(')
+          if type.include?("(")
             string
           else
             binary
           end
         end
 
-        assert_equal mapping.lookup('varchar(20)'), string
-        assert_equal mapping.lookup('varchar'), binary
+        assert_equal mapping.lookup("varchar(20)"), string
+        assert_equal mapping.lookup("varchar"), binary
       end
 
       def test_additional_lookup_args
@@ -92,16 +94,16 @@ module ActiveRecord
 
         mapping.register_type(/varchar/i) do |type, limit|
           if limit > 255
-            'text'
+            "text"
           else
-            'string'
+            "string"
           end
         end
-        mapping.alias_type(/string/i, 'varchar')
+        mapping.alias_type(/string/i, "varchar")
 
-        assert_equal mapping.lookup('varchar', 200), 'string'
-        assert_equal mapping.lookup('varchar', 400), 'text'
-        assert_equal mapping.lookup('string', 400), 'text'
+        assert_equal mapping.lookup("varchar", 200), "string"
+        assert_equal mapping.lookup("varchar", 400), "text"
+        assert_equal mapping.lookup("string", 400), "text"
       end
 
       def test_requires_value_or_block
@@ -115,13 +117,13 @@ module ActiveRecord
       def test_lookup_non_strings
         mapping = HashLookupTypeMap.new
 
-        mapping.register_type(1, 'string')
-        mapping.register_type(2, 'int')
+        mapping.register_type(1, "string")
+        mapping.register_type(2, "int")
         mapping.alias_type(3, 1)
 
-        assert_equal mapping.lookup(1), 'string'
-        assert_equal mapping.lookup(2), 'int'
-        assert_equal mapping.lookup(3), 'string'
+        assert_equal mapping.lookup(1), "string"
+        assert_equal mapping.lookup(2), "int"
+        assert_equal mapping.lookup(3), "string"
         assert_kind_of Type::Value, mapping.lookup(4)
       end
 
@@ -174,4 +176,3 @@ module ActiveRecord
     end
   end
 end
-
diff --git a/activemodel/test/cases/type/unsigned_integer_test.rb b/activerecord/test/cases/type/unsigned_integer_test.rb
index 026cb08a06..dd05cf3fff 100644
--- a/activemodel/test/cases/type/unsigned_integer_test.rb
+++ b/activerecord/test/cases/type/unsigned_integer_test.rb
@@ -1,9 +1,10 @@
+# frozen_string_literal: true
+
 require "cases/helper"
-require "active_model/type"
 
-module ActiveModel
+module ActiveRecord
   module Type
-    class UnsignedIntegerTest < ActiveModel::TestCase
+    class UnsignedIntegerTest < ActiveRecord::TestCase
       test "unsigned int max value is in range" do
         assert_equal(4294967295, UnsignedInteger.new.serialize(4294967295))
       end
diff --git a/activerecord/test/cases/type_test.rb b/activerecord/test/cases/type_test.rb
index d45a9b3141..93ae563c8b 100644
--- a/activerecord/test/cases/type_test.rb
+++ b/activerecord/test/cases/type_test.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require "cases/helper"
 
 class TypeTest < ActiveRecord::TestCase
diff --git a/activerecord/test/cases/types_test.rb b/activerecord/test/cases/types_test.rb
index 81fcf04a27..3f7fb0a604 100644
--- a/activerecord/test/cases/types_test.rb
+++ b/activerecord/test/cases/types_test.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require "cases/helper"
 
 module ActiveRecord
@@ -9,7 +11,7 @@ module ActiveRecord
           raise
         end
         klass = Class.new(ActiveRecord::Base) do
-          self.table_name = 'posts'
+          self.table_name = "posts"
           attribute :foo, type_which_cannot_go_to_the_database
         end
         model = klass.new
diff --git a/activerecord/test/cases/unconnected_test.rb b/activerecord/test/cases/unconnected_test.rb
index b210584644..f4d8be5897 100644
--- a/activerecord/test/cases/unconnected_test.rb
+++ b/activerecord/test/cases/unconnected_test.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require "cases/helper"
 
 class TestRecord < ActiveRecord::Base
diff --git a/activerecord/test/cases/unsafe_raw_sql_test.rb b/activerecord/test/cases/unsafe_raw_sql_test.rb
new file mode 100644
index 0000000000..72d4997d0b
--- /dev/null
+++ b/activerecord/test/cases/unsafe_raw_sql_test.rb
@@ -0,0 +1,299 @@
+# frozen_string_literal: true
+
+require "cases/helper"
+require "models/post"
+require "models/comment"
+
+class UnsafeRawSqlTest < ActiveRecord::TestCase
+  fixtures :posts, :comments
+
+  test "order: allows string column name" do
+    ids_expected = Post.order(Arel.sql("title")).pluck(:id)
+
+    ids_depr     = with_unsafe_raw_sql_deprecated { Post.order("title").pluck(:id) }
+    ids_disabled = with_unsafe_raw_sql_disabled   { Post.order("title").pluck(:id) }
+
+    assert_equal ids_expected, ids_depr
+    assert_equal ids_expected, ids_disabled
+  end
+
+  test "order: allows symbol column name" do
+    ids_expected = Post.order(Arel.sql("title")).pluck(:id)
+
+    ids_depr     = with_unsafe_raw_sql_deprecated { Post.order(:title).pluck(:id) }
+    ids_disabled = with_unsafe_raw_sql_disabled   { Post.order(:title).pluck(:id) }
+
+    assert_equal ids_expected, ids_depr
+    assert_equal ids_expected, ids_disabled
+  end
+
+  test "order: allows downcase symbol direction" do
+    ids_expected = Post.order(Arel.sql("title") => Arel.sql("asc")).pluck(:id)
+
+    ids_depr     = with_unsafe_raw_sql_deprecated { Post.order(title: :asc).pluck(:id) }
+    ids_disabled = with_unsafe_raw_sql_disabled   { Post.order(title: :asc).pluck(:id) }
+
+    assert_equal ids_expected, ids_depr
+    assert_equal ids_expected, ids_disabled
+  end
+
+  test "order: allows upcase symbol direction" do
+    ids_expected = Post.order(Arel.sql("title") => Arel.sql("ASC")).pluck(:id)
+
+    ids_depr     = with_unsafe_raw_sql_deprecated { Post.order(title: :ASC).pluck(:id) }
+    ids_disabled = with_unsafe_raw_sql_disabled   { Post.order(title: :ASC).pluck(:id) }
+
+    assert_equal ids_expected, ids_depr
+    assert_equal ids_expected, ids_disabled
+  end
+
+  test "order: allows string direction" do
+    ids_expected = Post.order(Arel.sql("title") => Arel.sql("asc")).pluck(:id)
+
+    ids_depr     = with_unsafe_raw_sql_deprecated { Post.order(title: "asc").pluck(:id) }
+    ids_disabled = with_unsafe_raw_sql_disabled   { Post.order(title: "asc").pluck(:id) }
+
+    assert_equal ids_expected, ids_depr
+    assert_equal ids_expected, ids_disabled
+  end
+
+  test "order: allows multiple columns" do
+    ids_expected = Post.order(Arel.sql("author_id"), Arel.sql("title")).pluck(:id)
+
+    ids_depr     = with_unsafe_raw_sql_deprecated { Post.order(:author_id, :title).pluck(:id) }
+    ids_disabled = with_unsafe_raw_sql_disabled   { Post.order(:author_id, :title).pluck(:id) }
+
+    assert_equal ids_expected, ids_depr
+    assert_equal ids_expected, ids_disabled
+  end
+
+  test "order: allows mixed" do
+    ids_expected = Post.order(Arel.sql("author_id"), Arel.sql("title") => Arel.sql("asc")).pluck(:id)
+
+    ids_depr     = with_unsafe_raw_sql_deprecated { Post.order(:author_id, title: :asc).pluck(:id) }
+    ids_disabled = with_unsafe_raw_sql_disabled   { Post.order(:author_id, title: :asc).pluck(:id) }
+
+    assert_equal ids_expected, ids_depr
+    assert_equal ids_expected, ids_disabled
+  end
+
+  test "order: allows table and column name" do
+    ids_expected = Post.order(Arel.sql("title")).pluck(:id)
+
+    ids_depr     = with_unsafe_raw_sql_deprecated { Post.order("posts.title").pluck(:id) }
+    ids_disabled = with_unsafe_raw_sql_disabled   { Post.order("posts.title").pluck(:id) }
+
+    assert_equal ids_expected, ids_depr
+    assert_equal ids_expected, ids_disabled
+  end
+
+  test "order: allows column name and direction in string" do
+    ids_expected = Post.order(Arel.sql("title desc")).pluck(:id)
+
+    ids_depr     = with_unsafe_raw_sql_deprecated { Post.order("title desc").pluck(:id) }
+    ids_disabled = with_unsafe_raw_sql_disabled   { Post.order("title desc").pluck(:id) }
+
+    assert_equal ids_expected, ids_depr
+    assert_equal ids_expected, ids_disabled
+  end
+
+  test "order: allows table name, column name and direction in string" do
+    ids_expected = Post.order(Arel.sql("title desc")).pluck(:id)
+
+    ids_depr     = with_unsafe_raw_sql_deprecated { Post.order("posts.title desc").pluck(:id) }
+    ids_disabled = with_unsafe_raw_sql_disabled   { Post.order("posts.title desc").pluck(:id) }
+
+    assert_equal ids_expected, ids_depr
+    assert_equal ids_expected, ids_disabled
+  end
+
+  test "order: disallows invalid column name" do
+    with_unsafe_raw_sql_disabled do
+      assert_raises(ActiveRecord::UnknownAttributeReference) do
+        Post.order("len(title) asc").pluck(:id)
+      end
+    end
+  end
+
+  test "order: disallows invalid direction" do
+    with_unsafe_raw_sql_disabled do
+      assert_raises(ArgumentError) do
+        Post.order(title: :foo).pluck(:id)
+      end
+    end
+  end
+
+  test "order: disallows invalid column with direction" do
+    with_unsafe_raw_sql_disabled do
+      assert_raises(ActiveRecord::UnknownAttributeReference) do
+        Post.order("len(title)" => :asc).pluck(:id)
+      end
+    end
+  end
+
+  test "order: always allows Arel" do
+    ids_depr     = with_unsafe_raw_sql_deprecated { Post.order(Arel.sql("length(title)")).pluck(:title) }
+    ids_disabled = with_unsafe_raw_sql_disabled   { Post.order(Arel.sql("length(title)")).pluck(:title) }
+
+    assert_equal ids_depr, ids_disabled
+  end
+
+  test "order: allows Arel.sql with binds" do
+    ids_expected = Post.order(Arel.sql("REPLACE(title, 'misc', 'zzzz'), id")).pluck(:id)
+
+    ids_depr     = with_unsafe_raw_sql_deprecated { Post.order([Arel.sql("REPLACE(title, ?, ?), id"), "misc", "zzzz"]).pluck(:id) }
+    ids_disabled = with_unsafe_raw_sql_disabled   { Post.order([Arel.sql("REPLACE(title, ?, ?), id"), "misc", "zzzz"]).pluck(:id) }
+
+    assert_equal ids_expected, ids_depr
+    assert_equal ids_expected, ids_disabled
+  end
+
+  test "order: disallows invalid bind statement" do
+    with_unsafe_raw_sql_disabled do
+      assert_raises(ActiveRecord::UnknownAttributeReference) do
+        Post.order(["REPLACE(title, ?, ?), id", "misc", "zzzz"]).pluck(:id)
+      end
+    end
+  end
+
+  test "order: disallows invalid Array arguments" do
+    with_unsafe_raw_sql_disabled do
+      assert_raises(ActiveRecord::UnknownAttributeReference) do
+        Post.order(["author_id", "length(title)"]).pluck(:id)
+      end
+    end
+  end
+
+  test "order: allows valid Array arguments" do
+    ids_expected = Post.order(Arel.sql("author_id, length(title)")).pluck(:id)
+
+    ids_depr     = with_unsafe_raw_sql_deprecated { Post.order(["author_id", Arel.sql("length(title)")]).pluck(:id) }
+    ids_disabled = with_unsafe_raw_sql_disabled   { Post.order(["author_id", Arel.sql("length(title)")]).pluck(:id) }
+
+    assert_equal ids_expected, ids_depr
+    assert_equal ids_expected, ids_disabled
+  end
+
+  test "order: logs deprecation warning for unrecognized column" do
+    with_unsafe_raw_sql_deprecated do
+      assert_deprecated(/Dangerous query method/) do
+        Post.order("length(title)")
+      end
+    end
+  end
+
+  test "pluck: allows string column name" do
+    titles_expected = Post.pluck(Arel.sql("title"))
+
+    titles_depr     = with_unsafe_raw_sql_deprecated { Post.pluck("title") }
+    titles_disabled = with_unsafe_raw_sql_disabled   { Post.pluck("title") }
+
+    assert_equal titles_expected, titles_depr
+    assert_equal titles_expected, titles_disabled
+  end
+
+  test "pluck: allows symbol column name" do
+    titles_expected = Post.pluck(Arel.sql("title"))
+
+    titles_depr     = with_unsafe_raw_sql_deprecated { Post.pluck(:title) }
+    titles_disabled = with_unsafe_raw_sql_disabled   { Post.pluck(:title) }
+
+    assert_equal titles_expected, titles_depr
+    assert_equal titles_expected, titles_disabled
+  end
+
+  test "pluck: allows multiple column names" do
+    values_expected = Post.pluck(Arel.sql("title"), Arel.sql("id"))
+
+    values_depr     = with_unsafe_raw_sql_deprecated { Post.pluck(:title, :id) }
+    values_disabled = with_unsafe_raw_sql_disabled   { Post.pluck(:title, :id) }
+
+    assert_equal values_expected, values_depr
+    assert_equal values_expected, values_disabled
+  end
+
+  test "pluck: allows column names with includes" do
+    values_expected = Post.includes(:comments).pluck(Arel.sql("title"), Arel.sql("id"))
+
+    values_depr     = with_unsafe_raw_sql_deprecated { Post.includes(:comments).pluck(:title, :id) }
+    values_disabled = with_unsafe_raw_sql_disabled   { Post.includes(:comments).pluck(:title, :id) }
+
+    assert_equal values_expected, values_depr
+    assert_equal values_expected, values_disabled
+  end
+
+  test "pluck: allows auto-generated attributes" do
+    values_expected = Post.pluck(Arel.sql("tags_count"))
+
+    values_depr     = with_unsafe_raw_sql_deprecated { Post.pluck(:tags_count) }
+    values_disabled = with_unsafe_raw_sql_disabled   { Post.pluck(:tags_count) }
+
+    assert_equal values_expected, values_depr
+    assert_equal values_expected, values_disabled
+  end
+
+  test "pluck: allows table and column names" do
+    titles_expected = Post.pluck(Arel.sql("title"))
+
+    titles_depr     = with_unsafe_raw_sql_deprecated { Post.pluck("posts.title") }
+    titles_disabled = with_unsafe_raw_sql_disabled   { Post.pluck("posts.title") }
+
+    assert_equal titles_expected, titles_depr
+    assert_equal titles_expected, titles_disabled
+  end
+
+  test "pluck: disallows invalid column name" do
+    with_unsafe_raw_sql_disabled do
+      assert_raises(ActiveRecord::UnknownAttributeReference) do
+        Post.pluck("length(title)")
+      end
+    end
+  end
+
+  test "pluck: disallows invalid column name amongst valid names" do
+    with_unsafe_raw_sql_disabled do
+      assert_raises(ActiveRecord::UnknownAttributeReference) do
+        Post.pluck(:title, "length(title)")
+      end
+    end
+  end
+
+  test "pluck: disallows invalid column names with includes" do
+    with_unsafe_raw_sql_disabled do
+      assert_raises(ActiveRecord::UnknownAttributeReference) do
+        Post.includes(:comments).pluck(:title, "length(title)")
+      end
+    end
+  end
+
+  test "pluck: always allows Arel" do
+    values_depr     = with_unsafe_raw_sql_deprecated { Post.includes(:comments).pluck(:title, Arel.sql("length(title)")) }
+    values_disabled = with_unsafe_raw_sql_disabled   { Post.includes(:comments).pluck(:title, Arel.sql("length(title)")) }
+
+    assert_equal values_depr, values_disabled
+  end
+
+  test "pluck: logs deprecation warning" do
+    with_unsafe_raw_sql_deprecated do
+      assert_deprecated(/Dangerous query method/) do
+        Post.includes(:comments).pluck(:title, "length(title)")
+      end
+    end
+  end
+
+  def with_unsafe_raw_sql_disabled(&blk)
+    with_config(:disabled, &blk)
+  end
+
+  def with_unsafe_raw_sql_deprecated(&blk)
+    with_config(:deprecated, &blk)
+  end
+
+  def with_config(new_value, &blk)
+    old_value = ActiveRecord::Base.allow_unsafe_raw_sql
+    ActiveRecord::Base.allow_unsafe_raw_sql = new_value
+    blk.call
+  ensure
+    ActiveRecord::Base.allow_unsafe_raw_sql = old_value
+  end
+end
diff --git a/activerecord/test/cases/validations/absence_validation_test.rb b/activerecord/test/cases/validations/absence_validation_test.rb
index c0b3750bcc..a997f8be9c 100644
--- a/activerecord/test/cases/validations/absence_validation_test.rb
+++ b/activerecord/test/cases/validations/absence_validation_test.rb
@@ -1,8 +1,10 @@
+# frozen_string_literal: true
+
 require "cases/helper"
-require 'models/face'
-require 'models/interest'
-require 'models/man'
-require 'models/topic'
+require "models/face"
+require "models/interest"
+require "models/man"
+require "models/topic"
 
 class AbsenceValidationTest < ActiveRecord::TestCase
   def test_non_association
@@ -52,7 +54,7 @@ class AbsenceValidationTest < ActiveRecord::TestCase
     end
 
     face_with_to_a = Face.new
-    def face_with_to_a.to_a; ['(/)', '(\)']; end
+    def face_with_to_a.to_a; ["(/)", '(\)']; end
 
     assert_nothing_raised { boy_klass.new(face: face_with_to_a).valid? }
   end
@@ -62,10 +64,10 @@ class AbsenceValidationTest < ActiveRecord::TestCase
       Interest.send(:attr_accessor, :token)
       Interest.validates_absence_of(:token)
 
-      interest = Interest.create!(topic: 'Thought Leadering')
+      interest = Interest.create!(topic: "Thought Leadering")
       assert interest.valid?
 
-      interest.token = 'tl'
+      interest.token = "tl"
 
       assert interest.invalid?
     end
diff --git a/activerecord/test/cases/validations/association_validation_test.rb b/activerecord/test/cases/validations/association_validation_test.rb
index 584a3dc0d8..80fe375ae5 100644
--- a/activerecord/test/cases/validations/association_validation_test.rb
+++ b/activerecord/test/cases/validations/association_validation_test.rb
@@ -1,8 +1,10 @@
+# frozen_string_literal: true
+
 require "cases/helper"
-require 'models/topic'
-require 'models/reply'
-require 'models/man'
-require 'models/interest'
+require "models/topic"
+require "models/reply"
+require "models/man"
+require "models/interest"
 
 class AssociationValidationTest < ActiveRecord::TestCase
   fixtures :topics
@@ -25,8 +27,8 @@ class AssociationValidationTest < ActiveRecord::TestCase
   end
 
   def test_validates_associated_one
-    Reply.validates :topic, :associated => true
-    Topic.validates_presence_of( :content )
+    Reply.validates :topic, associated: true
+    Topic.validates_presence_of(:content)
     r = Reply.new("title" => "A reply", "content" => "with content!")
     r.topic = Topic.create("title" => "uhohuhoh")
     assert !r.valid?
@@ -58,7 +60,7 @@ class AssociationValidationTest < ActiveRecord::TestCase
   end
 
   def test_validates_associated_with_custom_message_using_quotes
-    Reply.validates_associated :topic, :message=> "This string contains 'single' and \"double\" quotes"
+    Reply.validates_associated :topic, message: "This string contains 'single' and \"double\" quotes"
     Topic.validates_presence_of :content
     r = Reply.create("title" => "A reply", "content" => "with content!")
     r.topic = Topic.create("title" => "uhohuhoh")
@@ -80,8 +82,8 @@ class AssociationValidationTest < ActiveRecord::TestCase
     repair_validations(Interest) do
       # Note that Interest and Man have the :inverse_of option set
       Interest.validates_presence_of(:man)
-      man = Man.new(:name => 'John')
-      interest = man.interests.build(:topic => 'Airplanes')
+      man = Man.new(name: "John")
+      interest = man.interests.build(topic: "Airplanes")
       assert interest.valid?, "Expected interest to be valid, but was not. Interest should have a man object associated"
     end
   end
@@ -89,8 +91,8 @@ class AssociationValidationTest < ActiveRecord::TestCase
   def test_validates_presence_of_belongs_to_association__existing_parent
     repair_validations(Interest) do
       Interest.validates_presence_of(:man)
-      man = Man.create!(:name => 'John')
-      interest = man.interests.build(:topic => 'Airplanes')
+      man = Man.create!(name: "John")
+      interest = man.interests.build(topic: "Airplanes")
       assert interest.valid?, "Expected interest to be valid, but was not. Interest should have a man object associated"
     end
   end
diff --git a/activerecord/test/cases/validations/i18n_generate_message_validation_test.rb b/activerecord/test/cases/validations/i18n_generate_message_validation_test.rb
index 13d4d85afa..703c24b340 100644
--- a/activerecord/test/cases/validations/i18n_generate_message_validation_test.rb
+++ b/activerecord/test/cases/validations/i18n_generate_message_validation_test.rb
@@ -1,5 +1,7 @@
+# frozen_string_literal: true
+
 require "cases/helper"
-require 'models/topic'
+require "models/topic"
 
 class I18nGenerateMessageValidationTest < ActiveRecord::TestCase
   def setup
@@ -20,20 +22,20 @@ class I18nGenerateMessageValidationTest < ActiveRecord::TestCase
 
   # validates_associated: generate_message(attr_name, :invalid, :message => custom_message, :value => value)
   def test_generate_message_invalid_with_default_message
-    assert_equal 'is invalid', @topic.errors.generate_message(:title, :invalid, :value => 'title')
+    assert_equal "is invalid", @topic.errors.generate_message(:title, :invalid, value: "title")
   end
 
   def test_generate_message_invalid_with_custom_message
-    assert_equal 'custom message title', @topic.errors.generate_message(:title, :invalid, :message => 'custom message %{value}', :value => 'title')
+    assert_equal "custom message title", @topic.errors.generate_message(:title, :invalid, message: "custom message %{value}", value: "title")
   end
 
   # validates_uniqueness_of: generate_message(attr_name, :taken, :message => custom_message)
   def test_generate_message_taken_with_default_message
-    assert_equal "has already been taken", @topic.errors.generate_message(:title, :taken, :value => 'title')
+    assert_equal "has already been taken", @topic.errors.generate_message(:title, :taken, value: "title")
   end
 
   def test_generate_message_taken_with_custom_message
-    assert_equal 'custom message title', @topic.errors.generate_message(:title, :taken, :message => 'custom message %{value}', :value => 'title')
+    assert_equal "custom message title", @topic.errors.generate_message(:title, :taken, message: "custom message %{value}", value: "title")
   end
 
   # ActiveRecord#RecordInvalid exception
@@ -47,7 +49,7 @@ class I18nGenerateMessageValidationTest < ActiveRecord::TestCase
 
   test "RecordInvalid exception translation falls back to the :errors namespace" do
     reset_i18n_load_path do
-      I18n.backend.store_translations 'en', :errors => {:messages => {:record_invalid => 'fallback message'}}
+      I18n.backend.store_translations "en", errors: { messages: { record_invalid: "fallback message" } }
       topic = Topic.new
       topic.errors.add(:title, :blank)
       assert_equal "fallback message", ActiveRecord::RecordInvalid.new(topic).message
@@ -56,29 +58,29 @@ class I18nGenerateMessageValidationTest < ActiveRecord::TestCase
 
   test "translation for 'taken' can be overridden" do
     reset_i18n_load_path do
-      I18n.backend.store_translations "en", {errors: {attributes: {title: {taken: "Custom taken message" }}}}
-      assert_equal "Custom taken message", @topic.errors.generate_message(:title, :taken, :value => 'title')
+      I18n.backend.store_translations "en", errors: { attributes: { title: { taken: "Custom taken message" } } }
+      assert_equal "Custom taken message", @topic.errors.generate_message(:title, :taken, value: "title")
     end
   end
 
   test "translation for 'taken' can be overridden in activerecord scope" do
     reset_i18n_load_path do
-      I18n.backend.store_translations "en", {activerecord: {errors: {messages: {taken: "Custom taken message" }}}}
-      assert_equal "Custom taken message", @topic.errors.generate_message(:title, :taken, :value => 'title')
+      I18n.backend.store_translations "en", activerecord: { errors: { messages: { taken: "Custom taken message" } } }
+      assert_equal "Custom taken message", @topic.errors.generate_message(:title, :taken, value: "title")
     end
   end
 
   test "translation for 'taken' can be overridden in activerecord model scope" do
     reset_i18n_load_path do
-      I18n.backend.store_translations "en", {activerecord: {errors: {models: {topic: {taken: "Custom taken message" }}}}}
-      assert_equal "Custom taken message", @topic.errors.generate_message(:title, :taken, :value => 'title')
+      I18n.backend.store_translations "en", activerecord: { errors: { models: { topic: { taken: "Custom taken message" } } } }
+      assert_equal "Custom taken message", @topic.errors.generate_message(:title, :taken, value: "title")
     end
   end
 
   test "translation for 'taken' can be overridden in activerecord attributes scope" do
     reset_i18n_load_path do
-      I18n.backend.store_translations "en", {activerecord: {errors: {models: {topic: {attributes: {title: {taken: "Custom taken message" }}}}}}}
-      assert_equal "Custom taken message", @topic.errors.generate_message(:title, :taken, :value => 'title')
+      I18n.backend.store_translations "en", activerecord: { errors: { models: { topic: { attributes: { title: { taken: "Custom taken message" } } } } } }
+      assert_equal "Custom taken message", @topic.errors.generate_message(:title, :taken, value: "title")
     end
   end
 end
diff --git a/activerecord/test/cases/validations/i18n_validation_test.rb b/activerecord/test/cases/validations/i18n_validation_test.rb
index 5b5307489a..b7c52ea18c 100644
--- a/activerecord/test/cases/validations/i18n_validation_test.rb
+++ b/activerecord/test/cases/validations/i18n_validation_test.rb
@@ -1,6 +1,8 @@
+# frozen_string_literal: true
+
 require "cases/helper"
-require 'models/topic'
-require 'models/reply'
+require "models/topic"
+require "models/reply"
 
 class I18nValidationTest < ActiveRecord::TestCase
   repair_validations(Topic, Reply)
@@ -12,7 +14,7 @@ class I18nValidationTest < ActiveRecord::TestCase
     @old_load_path, @old_backend = I18n.load_path.dup, I18n.backend
     I18n.load_path.clear
     I18n.backend = I18n::Backend::Simple.new
-    I18n.backend.store_translations('en', :errors => {:messages => {:custom => nil}})
+    I18n.backend.store_translations("en", errors: { messages: { custom: nil } })
   end
 
   teardown do
@@ -21,12 +23,12 @@ class I18nValidationTest < ActiveRecord::TestCase
   end
 
   def unique_topic
-    @unique ||= Topic.create :title => 'unique!'
+    @unique ||= Topic.create title: "unique!"
   end
 
   def replied_topic
     @replied_topic ||= begin
-      topic = Topic.create(:title => "topic")
+      topic = Topic.create(title: "topic")
       topic.replies << Reply.new
       topic
     end
@@ -36,20 +38,20 @@ class I18nValidationTest < ActiveRecord::TestCase
   # are used to generate tests to keep things DRY
   #
   COMMON_CASES = [
-  # [ case,                                validation_options,            generate_message_options]
+    # [ case,                              validation_options,            generate_message_options]
     [ "given no options",                  {},                            {}],
-    [ "given custom message",              {:message => "custom"},        {:message => "custom"}],
-    [ "given if condition",                {:if     => lambda { true }},  {}],
-    [ "given unless condition",            {:unless => lambda { false }}, {}],
-    [ "given option that is not reserved", {:format => "jpg"},            {:format => "jpg" }],
-    [ "given on condition",                {on: [:create, :update] },     {}]
+    [ "given custom message",              { message: "custom" },        { message: "custom" }],
+    [ "given if condition",                { if: lambda { true } },  {}],
+    [ "given unless condition",            { unless: lambda { false } }, {}],
+    [ "given option that is not reserved", { format: "jpg" },            { format: "jpg" }],
+    [ "given on condition",                { on: [:create, :update] },     {}]
   ]
 
   COMMON_CASES.each do |name, validation_options, generate_message_options|
     test "validates_uniqueness_of on generated message #{name}" do
       Topic.validates_uniqueness_of :title, validation_options
       @topic.title = unique_topic.title
-      assert_called_with(@topic.errors, :generate_message, [:title, :taken, generate_message_options.merge(:value => 'unique!')]) do
+      assert_called_with(@topic.errors, :generate_message, [:title, :taken, generate_message_options.merge(value: "unique!")]) do
         @topic.valid?
       end
     end
@@ -58,27 +60,26 @@ class I18nValidationTest < ActiveRecord::TestCase
   COMMON_CASES.each do |name, validation_options, generate_message_options|
     test "validates_associated on generated message #{name}" do
       Topic.validates_associated :replies, validation_options
-      assert_called_with(replied_topic.errors, :generate_message, [:replies, :invalid, generate_message_options.merge(:value => replied_topic.replies)]) do
+      assert_called_with(replied_topic.errors, :generate_message, [:replies, :invalid, generate_message_options.merge(value: replied_topic.replies)]) do
         replied_topic.save
       end
     end
   end
 
   def test_validates_associated_finds_custom_model_key_translation
-    I18n.backend.store_translations 'en', :activerecord => {:errors => {:models => {:topic => {:attributes => {:replies => {:invalid => 'custom message'}}}}}}
-    I18n.backend.store_translations 'en', :activerecord => {:errors => {:messages => {:invalid => 'global message'}}}
+    I18n.backend.store_translations "en", activerecord: { errors: { models: { topic: { attributes: { replies: { invalid: "custom message" } } } } } }
+    I18n.backend.store_translations "en", activerecord: { errors: { messages: { invalid: "global message" } } }
 
     Topic.validates_associated :replies
     replied_topic.valid?
-    assert_equal ['custom message'], replied_topic.errors[:replies].uniq
+    assert_equal ["custom message"], replied_topic.errors[:replies].uniq
   end
 
   def test_validates_associated_finds_global_default_translation
-    I18n.backend.store_translations 'en', :activerecord => {:errors => {:messages => {:invalid => 'global message'}}}
+    I18n.backend.store_translations "en", activerecord: { errors: { messages: { invalid: "global message" } } }
 
     Topic.validates_associated :replies
     replied_topic.valid?
-    assert_equal ['global message'], replied_topic.errors[:replies]
+    assert_equal ["global message"], replied_topic.errors[:replies]
   end
-
 end
diff --git a/activerecord/test/cases/validations/length_validation_test.rb b/activerecord/test/cases/validations/length_validation_test.rb
index 78263fd955..87ce4c6f37 100644
--- a/activerecord/test/cases/validations/length_validation_test.rb
+++ b/activerecord/test/cases/validations/length_validation_test.rb
@@ -1,47 +1,48 @@
+# frozen_string_literal: true
+
 require "cases/helper"
-require 'models/owner'
-require 'models/pet'
-require 'models/person'
+require "models/owner"
+require "models/pet"
+require "models/person"
 
 class LengthValidationTest < ActiveRecord::TestCase
   fixtures :owners
 
   setup do
     @owner = Class.new(Owner) do
-      def self.name; 'Owner'; end
+      def self.name; "Owner"; end
     end
   end
 
-
   def test_validates_size_of_association
     assert_nothing_raised { @owner.validates_size_of :pets, minimum: 1 }
-    o = @owner.new('name' => 'nopets')
+    o = @owner.new("name" => "nopets")
     assert !o.save
     assert o.errors[:pets].any?
-    o.pets.build('name' => 'apet')
+    o.pets.build("name" => "apet")
     assert o.valid?
   end
 
   def test_validates_size_of_association_using_within
     assert_nothing_raised { @owner.validates_size_of :pets, within: 1..2 }
-    o = @owner.new('name' => 'nopets')
+    o = @owner.new("name" => "nopets")
     assert !o.save
     assert o.errors[:pets].any?
 
-    o.pets.build('name' => 'apet')
+    o.pets.build("name" => "apet")
     assert o.valid?
 
-    2.times { o.pets.build('name' => 'apet') }
+    2.times { o.pets.build("name" => "apet") }
     assert !o.save
     assert o.errors[:pets].any?
   end
 
   def test_validates_size_of_association_utf8
     @owner.validates_size_of :pets, minimum: 1
-    o = @owner.new('name' => 'あいうえおかきくけこ')
+    o = @owner.new("name" => "あいうえおかきくけこ")
     assert !o.save
     assert o.errors[:pets].any?
-    o.pets.build('name' => 'あいうえおかきくけこ')
+    o.pets.build("name" => "あいうえおかきくけこ")
     assert o.valid?
   end
 
@@ -55,7 +56,7 @@ class LengthValidationTest < ActiveRecord::TestCase
     assert owner.save
 
     pet_count = Pet.count
-    assert_not owner.update_attributes pets_attributes: [ {_destroy: 1, id: pet.id} ]
+    assert_not owner.update_attributes pets_attributes: [ { _destroy: 1, id: pet.id } ]
     assert_not owner.valid?
     assert owner.errors[:pets].any?
     assert_equal pet_count, Pet.count
@@ -67,11 +68,11 @@ class LengthValidationTest < ActiveRecord::TestCase
       Pet.validates_length_of(:name, minimum: 1)
       Pet.validates_length_of(:nickname, minimum: 1)
 
-      pet = Pet.create!(name: 'Fancy Pants', nickname: 'Fancy')
+      pet = Pet.create!(name: "Fancy Pants", nickname: "Fancy")
 
       assert pet.valid?
 
-      pet.nickname = ''
+      pet.nickname = ""
 
       assert pet.invalid?
     end
diff --git a/activerecord/test/cases/validations/presence_validation_test.rb b/activerecord/test/cases/validations/presence_validation_test.rb
index 868d111b8c..3ab1567b51 100644
--- a/activerecord/test/cases/validations/presence_validation_test.rb
+++ b/activerecord/test/cases/validations/presence_validation_test.rb
@@ -1,9 +1,11 @@
+# frozen_string_literal: true
+
 require "cases/helper"
-require 'models/man'
-require 'models/face'
-require 'models/interest'
-require 'models/speedometer'
-require 'models/dashboard'
+require "models/man"
+require "models/face"
+require "models/interest"
+require "models/speedometer"
+require "models/dashboard"
 
 class PresenceValidationTest < ActiveRecord::TestCase
   class Boy < Man; end
@@ -57,7 +59,7 @@ class PresenceValidationTest < ActiveRecord::TestCase
     dash = Dashboard.new
 
     # dashboard has to_a method
-    def dash.to_a; ['(/)', '(\)']; end
+    def dash.to_a; ["(/)", '(\)']; end
 
     s = speedometer.new
     s.dashboard = dash
@@ -71,10 +73,10 @@ class PresenceValidationTest < ActiveRecord::TestCase
       Interest.validates_presence_of(:topic)
       Interest.validates_presence_of(:abbreviation)
 
-      interest = Interest.create!(topic: 'Thought Leadering', abbreviation: 'tl')
+      interest = Interest.create!(topic: "Thought Leadering", abbreviation: "tl")
       assert interest.valid?
 
-      interest.abbreviation = ''
+      interest.abbreviation = ""
 
       assert interest.invalid?
     end
diff --git a/activerecord/test/cases/validations/uniqueness_validation_test.rb b/activerecord/test/cases/validations/uniqueness_validation_test.rb
index 4b0a590adb..a10567f066 100644
--- a/activerecord/test/cases/validations/uniqueness_validation_test.rb
+++ b/activerecord/test/cases/validations/uniqueness_validation_test.rb
@@ -1,11 +1,16 @@
+# frozen_string_literal: true
+
 require "cases/helper"
-require 'models/topic'
-require 'models/reply'
-require 'models/warehouse_thing'
-require 'models/guid'
-require 'models/event'
-require 'models/dashboard'
-require 'models/uuid_item'
+require "models/topic"
+require "models/reply"
+require "models/warehouse_thing"
+require "models/guid"
+require "models/event"
+require "models/dashboard"
+require "models/uuid_item"
+require "models/author"
+require "models/person"
+require "models/essay"
 
 class Wizard < ActiveRecord::Base
   self.abstract_class = true
@@ -26,7 +31,7 @@ end
 class ReplyTitle; end
 
 class ReplyWithTitleObject < Reply
-  validates_uniqueness_of :content, :scope => :title
+  validates_uniqueness_of :content, scope: :title
 
   def title; ReplyTitle.new; end
 end
@@ -38,13 +43,13 @@ end
 
 class BigIntTest < ActiveRecord::Base
   INT_MAX_VALUE = 2147483647
-  self.table_name = 'cars'
+  self.table_name = "cars"
   validates :engines_count, uniqueness: true, inclusion: { in: 0..INT_MAX_VALUE }
 end
 
 class BigIntReverseTest < ActiveRecord::Base
   INT_MAX_VALUE = 2147483647
-  self.table_name = 'cars'
+  self.table_name = "cars"
   validates :engines_count, inclusion: { in: 0..INT_MAX_VALUE }
   validates :engines_count, uniqueness: true
 end
@@ -57,14 +62,14 @@ class TopicWithAfterCreate < Topic
   after_create :set_author
 
   def set_author
-    update_attributes!(:author_name => "#{title} #{id}")
+    update_attributes!(author_name: "#{title} #{id}")
   end
 end
 
 class UniquenessValidationTest < ActiveRecord::TestCase
   INT_MAX_VALUE = 2147483647
 
-  fixtures :topics, 'warehouse-things'
+  fixtures :topics, "warehouse-things"
 
   repair_validations(Topic, Reply)
 
@@ -90,7 +95,7 @@ class UniquenessValidationTest < ActiveRecord::TestCase
     Topic.alias_attribute :new_title, :title
     Topic.validates_uniqueness_of(:new_title)
 
-    topic = Topic.new(new_title: 'abc')
+    topic = Topic.new(new_title: "abc")
     assert topic.valid?
   end
 
@@ -107,33 +112,33 @@ class UniquenessValidationTest < ActiveRecord::TestCase
   end
 
   def test_validates_uniqueness_with_validates
-    Topic.validates :title, :uniqueness => true
-    Topic.create!('title' => 'abc')
+    Topic.validates :title, uniqueness: true
+    Topic.create!("title" => "abc")
 
-    t2 = Topic.new('title' => 'abc')
+    t2 = Topic.new("title" => "abc")
     assert !t2.valid?
     assert t2.errors[:title]
   end
 
   def test_validate_uniqueness_when_integer_out_of_range
     entry = BigIntTest.create(engines_count: INT_MAX_VALUE + 1)
-    assert_equal entry.errors[:engines_count], ['is not included in the list']
+    assert_equal entry.errors[:engines_count], ["is not included in the list"]
   end
 
   def test_validate_uniqueness_when_integer_out_of_range_show_order_does_not_matter
     entry = BigIntReverseTest.create(engines_count: INT_MAX_VALUE + 1)
-    assert_equal entry.errors[:engines_count], ['is not included in the list']
+    assert_equal entry.errors[:engines_count], ["is not included in the list"]
   end
 
   def test_validates_uniqueness_with_newline_chars
-    Topic.validates_uniqueness_of(:title, :case_sensitive => false)
+    Topic.validates_uniqueness_of(:title, case_sensitive: false)
 
     t = Topic.new("title" => "new\nline")
     assert t.save, "Should save t as unique"
   end
 
   def test_validate_uniqueness_with_scope
-    Reply.validates_uniqueness_of(:content, :scope => "parent_id")
+    Reply.validates_uniqueness_of(:content, scope: "parent_id")
 
     t = Topic.create("title" => "I'm unique!")
 
@@ -151,8 +156,15 @@ class UniquenessValidationTest < ActiveRecord::TestCase
     assert r3.valid?, "Saving r3"
   end
 
+  def test_validate_uniqueness_with_scope_invalid_syntax
+    error = assert_raises(ArgumentError) do
+      Reply.validates_uniqueness_of(:content, scope: { parent_id: false })
+    end
+    assert_match(/Pass a symbol or an array of symbols instead/, error.to_s)
+  end
+
   def test_validate_uniqueness_with_object_scope
-    Reply.validates_uniqueness_of(:content, :scope => :topic)
+    Reply.validates_uniqueness_of(:content, scope: :topic)
 
     t = Topic.create("title" => "I'm unique!")
 
@@ -163,6 +175,19 @@ class UniquenessValidationTest < ActiveRecord::TestCase
     assert !r2.valid?, "Saving r2 first time"
   end
 
+  def test_validate_uniqueness_with_polymorphic_object_scope
+    Essay.validates_uniqueness_of(:name, scope: :writer)
+
+    a = Author.create(name: "Sergey")
+    p = Person.create(first_name: "Sergey")
+
+    e1 = a.essays.create(name: "Essay")
+    assert e1.valid?, "Saving e1"
+
+    e2 = p.essays.create(name: "Essay")
+    assert e2.valid?, "Saving e2"
+  end
+
   def test_validate_uniqueness_with_composed_attribute_scope
     r1 = ReplyWithTitleObject.create "title" => "r1", "content" => "hello world"
     assert r1.valid?, "Saving r1"
@@ -199,7 +224,7 @@ class UniquenessValidationTest < ActiveRecord::TestCase
   end
 
   def test_validate_uniqueness_with_scope_array
-    Reply.validates_uniqueness_of(:author_name, :scope => [:author_email_address, :parent_id])
+    Reply.validates_uniqueness_of(:author_name, scope: [:author_email_address, :parent_id])
 
     t = Topic.create("title" => "The earth is actually flat!")
 
@@ -223,7 +248,7 @@ class UniquenessValidationTest < ActiveRecord::TestCase
   end
 
   def test_validate_case_insensitive_uniqueness
-    Topic.validates_uniqueness_of(:title, :parent_id, :case_sensitive => false, :allow_nil => true)
+    Topic.validates_uniqueness_of(:title, :parent_id, case_sensitive: false, allow_nil: true)
 
     t = Topic.new("title" => "I'm unique!", :parent_id => 2)
     assert t.save, "Should save t as unique"
@@ -256,7 +281,7 @@ class UniquenessValidationTest < ActiveRecord::TestCase
     assert t_utf8.save, "Should save t_utf8 as unique"
 
     # If database hasn't UTF-8 character set, this test fails
-    if Topic.all.merge!(:select => 'LOWER(title) AS title').find(t_utf8.id).title == "я тоже уникальный!"
+    if Topic.all.merge!(select: "LOWER(title) AS title").find(t_utf8.id).title == "я тоже уникальный!"
       t2_utf8 = Topic.new("title" => "я тоже УНИКАЛЬНЫЙ!")
       assert !t2_utf8.valid?, "Shouldn't be valid"
       assert !t2_utf8.save, "Shouldn't save t2_utf8 as unique"
@@ -264,7 +289,7 @@ class UniquenessValidationTest < ActiveRecord::TestCase
   end
 
   def test_validate_case_sensitive_uniqueness_with_special_sql_like_chars
-    Topic.validates_uniqueness_of(:title, :case_sensitive => true)
+    Topic.validates_uniqueness_of(:title, case_sensitive: true)
 
     t = Topic.new("title" => "I'm unique!")
     assert t.save, "Should save t as unique"
@@ -277,7 +302,7 @@ class UniquenessValidationTest < ActiveRecord::TestCase
   end
 
   def test_validate_case_insensitive_uniqueness_with_special_sql_like_chars
-    Topic.validates_uniqueness_of(:title, :case_sensitive => false)
+    Topic.validates_uniqueness_of(:title, case_sensitive: false)
 
     t = Topic.new("title" => "I'm unique!")
     assert t.save, "Should save t as unique"
@@ -290,7 +315,7 @@ class UniquenessValidationTest < ActiveRecord::TestCase
   end
 
   def test_validate_case_sensitive_uniqueness
-    Topic.validates_uniqueness_of(:title, :case_sensitive => true, :allow_nil => true)
+    Topic.validates_uniqueness_of(:title, case_sensitive: true, allow_nil: true)
 
     t = Topic.new("title" => "I'm unique!")
     assert t.save, "Should save t as unique"
@@ -314,16 +339,16 @@ class UniquenessValidationTest < ActiveRecord::TestCase
   end
 
   def test_validate_case_sensitive_uniqueness_with_attribute_passed_as_integer
-    Topic.validates_uniqueness_of(:title, :case_sensitive => true)
-    Topic.create!('title' => 101)
+    Topic.validates_uniqueness_of(:title, case_sensitive: true)
+    Topic.create!("title" => 101)
 
-    t2 = Topic.new('title' => 101)
+    t2 = Topic.new("title" => 101)
     assert !t2.valid?
     assert t2.errors[:title]
   end
 
   def test_validate_uniqueness_with_non_standard_table_names
-    i1 = WarehouseThing.create(:value => 1000)
+    i1 = WarehouseThing.create(value: 1000)
     assert !i1.valid?, "i1 should not be valid"
     assert i1.errors[:value].any?, "Should not be empty"
   end
@@ -331,7 +356,7 @@ class UniquenessValidationTest < ActiveRecord::TestCase
   def test_validates_uniqueness_inside_scoping
     Topic.validates_uniqueness_of(:title)
 
-    Topic.where(:author_name => "David").scoping do
+    Topic.where(author_name: "David").scoping do
       t1 = Topic.new("title" => "I'm unique!", "author_name" => "Mary")
       assert t1.save
       t2 = Topic.new("title" => "I'm unique!", "author_name" => "David")
@@ -356,7 +381,7 @@ class UniquenessValidationTest < ActiveRecord::TestCase
 
       e2 = Event.create(title: "abcdefgh")
       assert_not e2.valid?, "Created an event whose title is not unique"
-    elsif current_adapter?(:Mysql2Adapter, :PostgreSQLAdapter, :SQLServerAdapter)
+    elsif current_adapter?(:Mysql2Adapter, :PostgreSQLAdapter, :OracleAdapter, :SQLServerAdapter)
       assert_raise(ActiveRecord::ValueTooLong) do
         Event.create(title: "abcdefgh")
       end
@@ -369,13 +394,13 @@ class UniquenessValidationTest < ActiveRecord::TestCase
 
   def test_validate_uniqueness_with_limit_and_utf8
     if current_adapter?(:SQLite3Adapter)
-      # Event.title has limit 5, but does SQLite doesn't truncate.
+      # Event.title has limit 5, but SQLite doesn't truncate.
       e1 = Event.create(title: "一二三四五六七八")
       assert e1.valid?, "Could not create an event with a unique 8 characters title"
 
       e2 = Event.create(title: "一二三四五六七八")
       assert_not e2.valid?, "Created an event whose title is not unique"
-    elsif current_adapter?(:Mysql2Adapter, :PostgreSQLAdapter, :SQLServerAdapter)
+    elsif current_adapter?(:Mysql2Adapter, :PostgreSQLAdapter, :OracleAdapter, :SQLServerAdapter)
       assert_raise(ActiveRecord::ValueTooLong) do
         Event.create(title: "一二三四五六七八")
       end
@@ -387,29 +412,29 @@ class UniquenessValidationTest < ActiveRecord::TestCase
   end
 
   def test_validate_straight_inheritance_uniqueness
-    w1 = IneptWizard.create(:name => "Rincewind", :city => "Ankh-Morpork")
+    w1 = IneptWizard.create(name: "Rincewind", city: "Ankh-Morpork")
     assert w1.valid?, "Saving w1"
 
     # Should use validation from base class (which is abstract)
-    w2 = IneptWizard.new(:name => "Rincewind", :city => "Quirm")
+    w2 = IneptWizard.new(name: "Rincewind", city: "Quirm")
     assert !w2.valid?, "w2 shouldn't be valid"
     assert w2.errors[:name].any?, "Should have errors for name"
     assert_equal ["has already been taken"], w2.errors[:name], "Should have uniqueness message for name"
 
-    w3 = Conjurer.new(:name => "Rincewind", :city => "Quirm")
+    w3 = Conjurer.new(name: "Rincewind", city: "Quirm")
     assert !w3.valid?, "w3 shouldn't be valid"
     assert w3.errors[:name].any?, "Should have errors for name"
     assert_equal ["has already been taken"], w3.errors[:name], "Should have uniqueness message for name"
 
-    w4 = Conjurer.create(:name => "The Amazing Bonko", :city => "Quirm")
+    w4 = Conjurer.create(name: "The Amazing Bonko", city: "Quirm")
     assert w4.valid?, "Saving w4"
 
-    w5 = Thaumaturgist.new(:name => "The Amazing Bonko", :city => "Lancre")
+    w5 = Thaumaturgist.new(name: "The Amazing Bonko", city: "Lancre")
     assert !w5.valid?, "w5 shouldn't be valid"
     assert w5.errors[:name].any?, "Should have errors for name"
     assert_equal ["has already been taken"], w5.errors[:name], "Should have uniqueness message for name"
 
-    w6 = Thaumaturgist.new(:name => "Mustrum Ridcully", :city => "Quirm")
+    w6 = Thaumaturgist.new(name: "Mustrum Ridcully", city: "Quirm")
     assert !w6.valid?, "w6 shouldn't be valid"
     assert w6.errors[:city].any?, "Should have errors for city"
     assert_equal ["has already been taken"], w6.errors[:city], "Should have uniqueness message for city"
@@ -439,7 +464,7 @@ class UniquenessValidationTest < ActiveRecord::TestCase
 
     topic = TopicWithUniqEvent.new(event: event)
     assert_not topic.valid?
-    assert_equal ['has already been taken'], topic.errors[:event]
+    assert_equal ["has already been taken"], topic.errors[:event]
   end
 
   def test_validate_uniqueness_on_empty_relation
@@ -501,30 +526,30 @@ class UniquenessValidationTest < ActiveRecord::TestCase
 
   def test_validate_uniqueness_with_after_create_performing_save
     TopicWithAfterCreate.validates_uniqueness_of(:title)
-    topic = TopicWithAfterCreate.create!(:title => "Title1")
+    topic = TopicWithAfterCreate.create!(title: "Title1")
     assert topic.author_name.start_with?("Title1")
 
-    topic2 = TopicWithAfterCreate.new(:title => "Title1")
+    topic2 = TopicWithAfterCreate.new(title: "Title1")
     refute topic2.valid?
     assert_equal(["has already been taken"], topic2.errors[:title])
   end
 
   def test_validate_uniqueness_uuid
     skip unless current_adapter?(:PostgreSQLAdapter)
-    item = UuidItem.create!(uuid: SecureRandom.uuid, title: 'item1')
-    item.update(title: 'item1-title2')
+    item = UuidItem.create!(uuid: SecureRandom.uuid, title: "item1")
+    item.update(title: "item1-title2")
     assert_empty item.errors
 
-    item2 = UuidValidatingItem.create!(uuid: SecureRandom.uuid, title: 'item2')
-    item2.update(title: 'item2-title2')
+    item2 = UuidValidatingItem.create!(uuid: SecureRandom.uuid, title: "item2")
+    item2.update(title: "item2-title2")
     assert_empty item2.errors
   end
 
   def test_validate_uniqueness_regular_id
-    item = CoolTopic.create!(title: 'MyItem')
+    item = CoolTopic.create!(title: "MyItem")
     assert_empty item.errors
 
-    item2 = CoolTopic.new(id: item.id, title: 'MyItem2')
+    item2 = CoolTopic.new(id: item.id, title: "MyItem2")
     refute item2.valid?
 
     assert_equal(["has already been taken"], item2.errors[:id])
diff --git a/activerecord/test/cases/validations_repair_helper.rb b/activerecord/test/cases/validations_repair_helper.rb
index b30666d876..6dc3b64b2b 100644
--- a/activerecord/test/cases/validations_repair_helper.rb
+++ b/activerecord/test/cases/validations_repair_helper.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActiveRecord
   module ValidationsRepairHelper
     extend ActiveSupport::Concern
diff --git a/activerecord/test/cases/validations_test.rb b/activerecord/test/cases/validations_test.rb
index 85e33d2218..14623c43d2 100644
--- a/activerecord/test/cases/validations_test.rb
+++ b/activerecord/test/cases/validations_test.rb
@@ -1,11 +1,13 @@
+# frozen_string_literal: true
+
 require "cases/helper"
-require 'models/topic'
-require 'models/reply'
-require 'models/person'
-require 'models/developer'
-require 'models/computer'
-require 'models/parrot'
-require 'models/company'
+require "models/topic"
+require "models/reply"
+require "models/person"
+require "models/developer"
+require "models/computer"
+require "models/parrot"
+require "models/company"
 
 class ValidationsTest < ActiveRecord::TestCase
   fixtures :topics, :developers
@@ -36,7 +38,7 @@ class ValidationsTest < ActiveRecord::TestCase
   end
 
   def test_valid_using_special_context
-    r = WrongReply.new(:title => "Valid title")
+    r = WrongReply.new(title: "Valid title")
     assert !r.valid?(:special_case)
     assert_equal "Invalid", r.errors[:author_name].join
 
@@ -53,7 +55,7 @@ class ValidationsTest < ActiveRecord::TestCase
   end
 
   def test_invalid_using_multiple_contexts
-    r = WrongReply.new(:title => 'Wrong Create')
+    r = WrongReply.new(title: "Wrong Create")
     assert r.invalid?([:special_case, :create])
     assert_equal "Invalid", r.errors[:author_name].join
     assert_equal "is Wrong Create", r.errors[:title].join
@@ -95,7 +97,7 @@ class ValidationsTest < ActiveRecord::TestCase
     assert_raise(ActiveRecord::RecordInvalid) do
       WrongReply.new.validate!(:special_case)
     end
-    r = WrongReply.new(:title => "Valid title", :author_name => "secret", :content => "Good")
+    r = WrongReply.new(title: "Valid title", author_name: "secret", content: "Good")
     assert r.validate!(:special_case)
   end
 
@@ -107,7 +109,7 @@ class ValidationsTest < ActiveRecord::TestCase
 
   def test_exception_on_create_bang_with_block
     assert_raise(ActiveRecord::RecordInvalid) do
-      WrongReply.create!({ "title" => "OK" }) do |r|
+      WrongReply.create!("title" => "OK") do |r|
         r.content = nil
       end
     end
@@ -124,7 +126,7 @@ class ValidationsTest < ActiveRecord::TestCase
   def test_save_without_validation
     reply = WrongReply.new
     assert !reply.save
-    assert reply.save(:validate => false)
+    assert reply.save(validate: false)
   end
 
   def test_validates_acceptance_of_with_non_existent_table
@@ -156,22 +158,34 @@ class ValidationsTest < ActiveRecord::TestCase
   end
 
   def test_numericality_validation_with_mutation
-    Topic.class_eval do
+    klass = Class.new(Topic) do
       attribute :wibble, :string
       validates_numericality_of :wibble, only_integer: true
     end
 
-    topic = Topic.new(wibble: '123-4567')
-    topic.wibble.gsub!('-', '')
+    topic = klass.new(wibble: "123-4567")
+    topic.wibble.gsub!("-", "")
 
     assert topic.valid?
-  ensure
-    Topic.reset_column_information
+  end
+
+  def test_numericality_validation_checks_against_raw_value
+    klass = Class.new(Topic) do
+      def self.model_name
+        ActiveModel::Name.new(self, nil, "Topic")
+      end
+      attribute :wibble, :decimal, scale: 2, precision: 9
+      validates_numericality_of :wibble, greater_than_or_equal_to: BigDecimal("97.18")
+    end
+
+    assert_not klass.new(wibble: "97.179").valid?
+    assert_not klass.new(wibble: 97.179).valid?
+    assert_not klass.new(wibble: BigDecimal("97.179")).valid?
   end
 
   def test_acceptance_validator_doesnt_require_db_connection
     klass = Class.new(ActiveRecord::Base) do
-      self.table_name = 'posts'
+      self.table_name = "posts"
     end
     klass.reset_column_information
 
diff --git a/activerecord/test/cases/view_test.rb b/activerecord/test/cases/view_test.rb
index f3c2d2f30e..7e2d66c62a 100644
--- a/activerecord/test/cases/view_test.rb
+++ b/activerecord/test/cases/view_test.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require "cases/helper"
 require "models/book"
 require "support/schema_dumping_helper"
@@ -11,20 +13,21 @@ module ViewBehavior
   end
 
   class Ebook < ActiveRecord::Base
+    self.table_name = "ebooks'"
     self.primary_key = "id"
   end
 
   def setup
     super
     @connection = ActiveRecord::Base.connection
-    create_view "ebooks", <<-SQL
+    create_view "ebooks'", <<-SQL
       SELECT id, name, status FROM books WHERE format = 'ebook'
     SQL
   end
 
   def teardown
     super
-    drop_view "ebooks"
+    drop_view "ebooks'"
   end
 
   def test_reading
@@ -44,8 +47,7 @@ module ViewBehavior
 
   def test_table_exists
     view_name = Ebook.table_name
-    # TODO: switch this assertion around once we changed #tables to not return views.
-    ActiveSupport::Deprecation.silence { assert @connection.table_exists?(view_name), "'#{view_name}' table should exist" }
+    assert_not @connection.table_exists?(view_name), "'#{view_name}' table should not exist"
   end
 
   def test_views_ara_valid_data_sources
@@ -60,157 +62,163 @@ module ViewBehavior
   end
 
   def test_attributes
-    assert_equal({"id" => 2, "name" => "Ruby for Rails", "status" => 0},
+    assert_equal({ "id" => 2, "name" => "Ruby for Rails", "status" => 0 },
                  Ebook.first.attributes)
   end
 
   def test_does_not_assume_id_column_as_primary_key
     model = Class.new(ActiveRecord::Base) do
-      self.table_name = "ebooks"
+      self.table_name = "ebooks'"
     end
     assert_nil model.primary_key
   end
 
   def test_does_not_dump_view_as_table
-    schema = dump_table_schema "ebooks"
-    assert_no_match %r{create_table "ebooks"}, schema
+    schema = dump_table_schema "ebooks'"
+    assert_no_match %r{create_table "ebooks'"}, schema
   end
-end
-
-if ActiveRecord::Base.connection.supports_views?
-class ViewWithPrimaryKeyTest < ActiveRecord::TestCase
-  include ViewBehavior
 
   private
-  def create_view(name, query)
-    @connection.execute "CREATE VIEW #{name} AS #{query}"
-  end
-
-  def drop_view(name)
-    @connection.execute "DROP VIEW #{name}" if @connection.view_exists? name
-  end
+    def quote_table_name(name)
+      @connection.quote_table_name(name)
+    end
 end
 
-class ViewWithoutPrimaryKeyTest < ActiveRecord::TestCase
-  include SchemaDumpingHelper
-  fixtures :books
-
-  class Paperback < ActiveRecord::Base; end
-
-  setup do
-    @connection = ActiveRecord::Base.connection
-    @connection.execute <<-SQL
-      CREATE VIEW paperbacks
-        AS SELECT name, status FROM books WHERE format = 'paperback'
-    SQL
-  end
-
-  teardown do
-    @connection.execute "DROP VIEW paperbacks" if @connection.view_exists? "paperbacks"
-  end
-
-  def test_reading
-    books = Paperback.all
-    assert_equal ["Agile Web Development with Rails"], books.map(&:name)
-  end
+if ActiveRecord::Base.connection.supports_views?
+  class ViewWithPrimaryKeyTest < ActiveRecord::TestCase
+    include ViewBehavior
 
-  def test_views
-    assert_equal [Paperback.table_name], @connection.views
-  end
+    private
+      def create_view(name, query)
+        @connection.execute "CREATE VIEW #{quote_table_name(name)} AS #{query}"
+      end
 
-  def test_view_exists
-    view_name = Paperback.table_name
-    assert @connection.view_exists?(view_name), "'#{view_name}' view should exist"
+      def drop_view(name)
+        @connection.execute "DROP VIEW #{quote_table_name(name)}" if @connection.view_exists? name
+      end
   end
 
-  def test_table_exists
-    view_name = Paperback.table_name
-    # TODO: switch this assertion around once we changed #tables to not return views.
-    ActiveSupport::Deprecation.silence { assert @connection.table_exists?(view_name), "'#{view_name}' table should exist" }    
-  end
+  class ViewWithoutPrimaryKeyTest < ActiveRecord::TestCase
+    include SchemaDumpingHelper
+    fixtures :books
 
-  def test_column_definitions
-    assert_equal([["name", :string],
-                  ["status", :integer]], Paperback.columns.map { |c| [c.name, c.type] })
-  end
+    class Paperback < ActiveRecord::Base; end
 
-  def test_attributes
-    assert_equal({"name" => "Agile Web Development with Rails", "status" => 2},
-                 Paperback.first.attributes)
-  end
+    setup do
+      @connection = ActiveRecord::Base.connection
+      @connection.execute <<-SQL
+        CREATE VIEW paperbacks
+          AS SELECT name, status FROM books WHERE format = 'paperback'
+      SQL
+    end
 
-  def test_does_not_have_a_primary_key
-    assert_nil Paperback.primary_key
-  end
+    teardown do
+      @connection.execute "DROP VIEW paperbacks" if @connection.view_exists? "paperbacks"
+    end
 
-  def test_does_not_dump_view_as_table
-    schema = dump_table_schema "paperbacks"
-    assert_no_match %r{create_table "paperbacks"}, schema
-  end
-end
+    def test_reading
+      books = Paperback.all
+      assert_equal ["Agile Web Development with Rails"], books.map(&:name)
+    end
 
-# sqlite dose not support CREATE, INSERT, and DELETE for VIEW
-if current_adapter?(:Mysql2Adapter, :PostgreSQLAdapter)
-class UpdateableViewTest < ActiveRecord::TestCase
-  self.use_transactional_tests = false
-  fixtures :books
+    def test_views
+      assert_equal [Paperback.table_name], @connection.views
+    end
 
-  class PrintedBook < ActiveRecord::Base
-    self.primary_key = "id"
-  end
+    def test_view_exists
+      view_name = Paperback.table_name
+      assert @connection.view_exists?(view_name), "'#{view_name}' view should exist"
+    end
 
-  setup do
-    @connection = ActiveRecord::Base.connection
-    @connection.execute <<-SQL
-      CREATE VIEW printed_books
-        AS SELECT id, name, status, format FROM books WHERE format = 'paperback'
-    SQL
-  end
+    def test_table_exists
+      view_name = Paperback.table_name
+      assert_not @connection.table_exists?(view_name), "'#{view_name}' table should not exist"
+    end
 
-  teardown do
-    @connection.execute "DROP VIEW printed_books" if @connection.view_exists? "printed_books"
-  end
+    def test_column_definitions
+      assert_equal([["name", :string],
+                    ["status", :integer]], Paperback.columns.map { |c| [c.name, c.type] })
+    end
 
-  def test_update_record
-    book = PrintedBook.first
-    book.name = "AWDwR"
-    book.save!
-    book.reload
-    assert_equal "AWDwR", book.name
-  end
+    def test_attributes
+      assert_equal({ "name" => "Agile Web Development with Rails", "status" => 2 },
+                   Paperback.first.attributes)
+    end
 
-  def test_insert_record
-    PrintedBook.create! name: "Rails in Action", status: 0, format: "paperback"
+    def test_does_not_have_a_primary_key
+      assert_nil Paperback.primary_key
+    end
 
-    new_book = PrintedBook.last
-    assert_equal "Rails in Action", new_book.name
+    def test_does_not_dump_view_as_table
+      schema = dump_table_schema "paperbacks"
+      assert_no_match %r{create_table "paperbacks"}, schema
+    end
   end
 
-  def test_update_record_to_fail_view_conditions
-    book = PrintedBook.first
-    book.format = "ebook"
-    book.save!
-
-    assert_raises ActiveRecord::RecordNotFound do
-      book.reload
+  # sqlite dose not support CREATE, INSERT, and DELETE for VIEW
+  if current_adapter?(:Mysql2Adapter, :SQLServerAdapter) ||
+      current_adapter?(:PostgreSQLAdapter) && ActiveRecord::Base.connection.postgresql_version >= 90300
+
+    class UpdateableViewTest < ActiveRecord::TestCase
+      self.use_transactional_tests = false
+      fixtures :books
+
+      class PrintedBook < ActiveRecord::Base
+        self.primary_key = "id"
+      end
+
+      setup do
+        @connection = ActiveRecord::Base.connection
+        @connection.execute <<-SQL
+          CREATE VIEW printed_books
+            AS SELECT id, name, status, format FROM books WHERE format = 'paperback'
+        SQL
+      end
+
+      teardown do
+        @connection.execute "DROP VIEW printed_books" if @connection.view_exists? "printed_books"
+      end
+
+      def test_update_record
+        book = PrintedBook.first
+        book.name = "AWDwR"
+        book.save!
+        book.reload
+        assert_equal "AWDwR", book.name
+      end
+
+      def test_insert_record
+        PrintedBook.create! name: "Rails in Action", status: 0, format: "paperback"
+
+        new_book = PrintedBook.last
+        assert_equal "Rails in Action", new_book.name
+      end
+
+      def test_update_record_to_fail_view_conditions
+        book = PrintedBook.first
+        book.format = "ebook"
+        book.save!
+
+        assert_raises ActiveRecord::RecordNotFound do
+          book.reload
+        end
+      end
     end
-  end
-end
-end # end fo `if current_adapter?(:Mysql2Adapter, :PostgreSQLAdapter)`
-end # end fo `if ActiveRecord::Base.connection.supports_views?`
+  end # end of `if current_adapter?(:Mysql2Adapter, :PostgreSQLAdapter, :SQLServerAdapter)`
+end # end of `if ActiveRecord::Base.connection.supports_views?`
 
 if ActiveRecord::Base.connection.respond_to?(:supports_materialized_views?) &&
     ActiveRecord::Base.connection.supports_materialized_views?
-class MaterializedViewTest < ActiveRecord::PostgreSQLTestCase
-  include ViewBehavior
+  class MaterializedViewTest < ActiveRecord::PostgreSQLTestCase
+    include ViewBehavior
 
-  private
-  def create_view(name, query)
-    @connection.execute "CREATE MATERIALIZED VIEW #{name} AS #{query}"
-  end
+    private
+      def create_view(name, query)
+        @connection.execute "CREATE MATERIALIZED VIEW #{quote_table_name(name)} AS #{query}"
+      end
 
-  def drop_view(name)
-    @connection.execute "DROP MATERIALIZED VIEW #{name}" if @connection.view_exists? name
+      def drop_view(name)
+        @connection.execute "DROP MATERIALIZED VIEW #{quote_table_name(name)}" if @connection.view_exists? name
+      end
   end
 end
-end
diff --git a/activerecord/test/cases/yaml_serialization_test.rb b/activerecord/test/cases/yaml_serialization_test.rb
index d1c9a00786..578881f754 100644
--- a/activerecord/test/cases/yaml_serialization_test.rb
+++ b/activerecord/test/cases/yaml_serialization_test.rb
@@ -1,15 +1,17 @@
-require 'cases/helper'
-require 'models/topic'
-require 'models/reply'
-require 'models/post'
-require 'models/author'
+# frozen_string_literal: true
+
+require "cases/helper"
+require "models/topic"
+require "models/reply"
+require "models/post"
+require "models/author"
 
 class YamlSerializationTest < ActiveRecord::TestCase
-  fixtures :topics, :authors, :posts
+  fixtures :topics, :authors, :author_addresses, :posts
 
   def test_to_yaml_with_time_with_zone_should_not_raise_exception
     with_timezone_config aware_attributes: true, zone: "Pacific Time (US & Canada)" do
-      topic = Topic.new(:written_on => DateTime.now)
+      topic = Topic.new(written_on: DateTime.now)
       assert_nothing_raised { topic.to_yaml }
     end
   end
@@ -22,8 +24,8 @@ class YamlSerializationTest < ActiveRecord::TestCase
   end
 
   def test_roundtrip_serialized_column
-    topic = Topic.new(:content => {:omg=>:lol})
-    assert_equal({:omg=>:lol}, YAML.load(YAML.dump(topic)).content)
+    topic = Topic.new(content: { omg: :lol })
+    assert_equal({ omg: :lol }, YAML.load(YAML.dump(topic)).content)
   end
 
   def test_psych_roundtrip
@@ -67,16 +69,16 @@ class YamlSerializationTest < ActiveRecord::TestCase
     assert_not topic.new_record?, "Saved records are not new"
     assert_not YAML.load(YAML.dump(topic)).new_record?, "Saved record should not be new after deserialization"
 
-    topic = Topic.select('title').last
+    topic = Topic.select("title").last
 
     assert_not topic.new_record?, "Loaded records without ID are not new"
     assert_not YAML.load(YAML.dump(topic)).new_record?, "Record should not be new after deserialization"
   end
 
   def test_types_of_virtual_columns_are_not_changed_on_round_trip
-    author = Author.select('authors.*, count(posts.id) as posts_count')
+    author = Author.select("authors.*, count(posts.id) as posts_count")
       .joins(:posts)
-      .group('authors.id')
+      .group("authors.id")
       .first
     dumped = YAML.load(YAML.dump(author))
 
@@ -88,14 +90,14 @@ class YamlSerializationTest < ActiveRecord::TestCase
     coder = {}
     Topic.first.encode_with(coder)
 
-    assert coder['active_record_yaml_version']
+    assert coder["active_record_yaml_version"]
   end
 
   def test_deserializing_rails_41_yaml
     topic = YAML.load(yaml_fixture("rails_4_1"))
 
     assert topic.new_record?
-    assert_equal nil, topic.id
+    assert_nil topic.id
     assert_equal "The First Topic", topic.title
     assert_equal({ omg: :lol }, topic.content)
   end
@@ -119,13 +121,21 @@ class YamlSerializationTest < ActiveRecord::TestCase
     assert_equal author.changes, dumped.changes
   end
 
-  private
+  def test_yaml_encoding_keeps_false_values
+    topic = Topic.first
+    topic.approved = false
+    dumped = YAML.load(YAML.dump(topic))
 
-  def yaml_fixture(file_name)
-    path = File.expand_path(
-      "../../support/yaml_compatibility_fixtures/#{file_name}.yml",
-      __FILE__
-    )
-    File.read(path)
+    assert_equal false, dumped.approved
   end
+
+  private
+
+    def yaml_fixture(file_name)
+      path = File.expand_path(
+        "../support/yaml_compatibility_fixtures/#{file_name}.yml",
+        __dir__
+      )
+      File.read(path)
+    end
 end
diff --git a/activerecord/test/config.example.yml b/activerecord/test/config.example.yml
index 58e2d45748..4bcb2aeea6 100644
--- a/activerecord/test/config.example.yml
+++ b/activerecord/test/config.example.yml
@@ -77,6 +77,9 @@ connections:
   postgresql:
     arunit:
       min_messages: warning
+    arunit_without_prepared_statements:
+      min_messages: warning
+      prepared_statements: false
     arunit2:
       min_messages: warning
 
diff --git a/activerecord/test/config.rb b/activerecord/test/config.rb
index 6e2e8b2145..72cdfb16ef 100644
--- a/activerecord/test/config.rb
+++ b/activerecord/test/config.rb
@@ -1,4 +1,6 @@
-TEST_ROOT       = File.expand_path(File.dirname(__FILE__))
+# frozen_string_literal: true
+
+TEST_ROOT       = __dir__
 ASSETS_ROOT     = TEST_ROOT + "/assets"
 FIXTURES_ROOT   = TEST_ROOT + "/fixtures"
 MIGRATIONS_ROOT = TEST_ROOT + "/migrations"
diff --git a/activerecord/test/fixtures/all/namespaced/accounts.yml b/activerecord/test/fixtures/all/namespaced/accounts.yml
new file mode 100644
index 0000000000..9e341a15af
--- /dev/null
+++ b/activerecord/test/fixtures/all/namespaced/accounts.yml
@@ -0,0 +1,2 @@
+signals37:
+  name: 37signals
diff --git a/activerecord/test/fixtures/binaries.yml b/activerecord/test/fixtures/binaries.yml
index ec8f2facdc..53b7883369 100644
--- a/activerecord/test/fixtures/binaries.yml
+++ b/activerecord/test/fixtures/binaries.yml
@@ -131,3 +131,7 @@ flowers:
     SgCUASgCUASgCUASgAC74PbXOTvE5/En7jpSoLE8/wBn7uPJjKyj46T9D/NT
     pKsXyQzxNpdNP0/akB5484WkMKh4RfXG4UafNmH7b0UxWMrb7Nxg6rl9Z/Im
     w+vWq0iscQwxQroiUIvkKsRZQBKAJQBKAJQB/9k=
+
+binary_helper:
+  id: 2
+  data: <%= binary(ASSETS_ROOT + "/flowers.jpg") %>
diff --git a/activerecord/test/fixtures/books.yml b/activerecord/test/fixtures/books.yml
index a304fba399..699623a6f9 100644
--- a/activerecord/test/fixtures/books.yml
+++ b/activerecord/test/fixtures/books.yml
@@ -9,6 +9,7 @@ awdr:
   author_visibility: :visible
   illustrator_visibility: :visible
   font_size: :medium
+  difficulty: :medium
 
 rfr:
   author_id: 1
@@ -24,6 +25,7 @@ ddd:
   name: "Domain-Driven Design"
   format: "hardcover"
   status: 2
+  read_status: "forgotten"
 
 tlg:
   author_id: 1
diff --git a/activerecord/test/fixtures/naked/yml/courses_with_invalid_key.yml b/activerecord/test/fixtures/naked/yml/courses_with_invalid_key.yml
new file mode 100644
index 0000000000..6f9da79b45
--- /dev/null
+++ b/activerecord/test/fixtures/naked/yml/courses_with_invalid_key.yml
@@ -0,0 +1,3 @@
+one:
+  id: 1
+two: ['not a hash']
diff --git a/activerecord/test/fixtures/naked/yml/parrots.yml b/activerecord/test/fixtures/naked/yml/parrots.yml
index 3e10331105..76f66e01ae 100644
--- a/activerecord/test/fixtures/naked/yml/parrots.yml
+++ b/activerecord/test/fixtures/naked/yml/parrots.yml
@@ -1,2 +1,3 @@
 george:
   arrr: "Curious George"
+  foobar: Foobar
diff --git a/activerecord/test/fixtures/other_dogs.yml b/activerecord/test/fixtures/other_dogs.yml
new file mode 100644
index 0000000000..b576861929
--- /dev/null
+++ b/activerecord/test/fixtures/other_dogs.yml
@@ -0,0 +1,2 @@
+lassie:
+  id: 1
diff --git a/activerecord/test/fixtures/other_posts.yml b/activerecord/test/fixtures/other_posts.yml
index 39ff763547..3e11a33802 100644
--- a/activerecord/test/fixtures/other_posts.yml
+++ b/activerecord/test/fixtures/other_posts.yml
@@ -5,3 +5,4 @@ second_welcome:
   author_id: 1
   title: Welcome to the another weblog
   body: It's really nice today
+  comments_count: 1
diff --git a/activerecord/test/fixtures/posts.yml b/activerecord/test/fixtures/posts.yml
index 86d46f753a..8d7e1e0ae7 100644
--- a/activerecord/test/fixtures/posts.yml
+++ b/activerecord/test/fixtures/posts.yml
@@ -28,6 +28,7 @@ sti_comments:
   author_id: 1
   title: sti comments
   body: hello
+  comments_count: 5
   type: Post
 
 sti_post_and_comments:
@@ -35,6 +36,7 @@ sti_post_and_comments:
   author_id: 1
   title: sti me
   body: hello
+  comments_count: 2
   type: StiPost
 
 sti_habtm:
@@ -50,6 +52,8 @@ eager_other:
   title: eager loading with OR'd conditions
   body: hello
   type: Post
+  comments_count: 1
+  tags_count: 3
 
 misc_by_bob:
   id: 8
@@ -57,6 +61,7 @@ misc_by_bob:
   title: misc post by bob
   body: hello
   type: Post
+  tags_count: 1
 
 misc_by_mary:
   id: 9
@@ -64,6 +69,7 @@ misc_by_mary:
   title: misc post by mary
   body: hello
   type: Post
+  tags_count: 1
 
 other_by_bob:
   id: 10
@@ -71,6 +77,7 @@ other_by_bob:
   title: other post by bob
   body: hello
   type: Post
+  tags_count: 1
 
 other_by_mary:
   id: 11
@@ -78,3 +85,4 @@ other_by_mary:
   title: other post by mary
   body: hello
   type: Post
+  tags_count: 1
diff --git a/activerecord/test/fixtures/reserved_words/values.yml b/activerecord/test/fixtures/reserved_words/values.yml
index 7d109609ab..9ed9e5edc5 100644
--- a/activerecord/test/fixtures/reserved_words/values.yml
+++ b/activerecord/test/fixtures/reserved_words/values.yml
@@ -1,7 +1,7 @@
 values1:
-  id: 1
+  as: 1
   group_id: 2
 
 values2:
-  id: 2
+  as: 2
   group_id: 1
diff --git a/activerecord/test/fixtures/subscribers.yml b/activerecord/test/fixtures/subscribers.yml
index c6a8c2fa24..0f6e0cd48e 100644
--- a/activerecord/test/fixtures/subscribers.yml
+++ b/activerecord/test/fixtures/subscribers.yml
@@ -6,6 +6,6 @@ second:
   nick: webster132
   name: David Heinemeier Hansson
 
-thrid:
+third:
   nick: swistak
   name: Marcin Raczkowski
\ No newline at end of file
diff --git a/activerecord/test/migrations/10_urban/9_add_expressions.rb b/activerecord/test/migrations/10_urban/9_add_expressions.rb
index e908c9eabc..4b0d5fb6fa 100644
--- a/activerecord/test/migrations/10_urban/9_add_expressions.rb
+++ b/activerecord/test/migrations/10_urban/9_add_expressions.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class AddExpressions < ActiveRecord::Migration::Current
   def self.up
     create_table("expressions") do |t|
diff --git a/activerecord/test/migrations/decimal/1_give_me_big_numbers.rb b/activerecord/test/migrations/decimal/1_give_me_big_numbers.rb
index 549647de86..b892f50e41 100644
--- a/activerecord/test/migrations/decimal/1_give_me_big_numbers.rb
+++ b/activerecord/test/migrations/decimal/1_give_me_big_numbers.rb
@@ -1,10 +1,12 @@
+# frozen_string_literal: true
+
 class GiveMeBigNumbers < ActiveRecord::Migration::Current
   def self.up
     create_table :big_numbers do |table|
-      table.column :bank_balance, :decimal, :precision => 10, :scale => 2
-      table.column :big_bank_balance, :decimal, :precision => 15, :scale => 2
-      table.column :world_population, :decimal, :precision => 10
-      table.column :my_house_population, :decimal, :precision => 2
+      table.column :bank_balance, :decimal, precision: 10, scale: 2
+      table.column :big_bank_balance, :decimal, precision: 15, scale: 2
+      table.column :world_population, :decimal, precision: 10
+      table.column :my_house_population, :decimal, precision: 2
       table.column :value_of_e, :decimal
     end
   end
diff --git a/activerecord/test/migrations/empty/.gitkeep b/activerecord/test/migrations/empty/.keep
index e69de29bb2..e69de29bb2 100644
--- a/activerecord/test/migrations/empty/.gitkeep
+++ b/activerecord/test/migrations/empty/.keep
diff --git a/activerecord/test/migrations/magic/1_currencies_have_symbols.rb b/activerecord/test/migrations/magic/1_currencies_have_symbols.rb
index 53b263bf55..2ba2875751 100644
--- a/activerecord/test/migrations/magic/1_currencies_have_symbols.rb
+++ b/activerecord/test/migrations/magic/1_currencies_have_symbols.rb
@@ -1,9 +1,10 @@
+# frozen_string_literal: true
 # coding: ISO-8859-15
 
 class CurrenciesHaveSymbols < ActiveRecord::Migration::Current
   def self.up
-    # We use � for default currency symbol
-    add_column "currencies", "symbol", :string, :default => "�"
+    # We use € for default currency symbol
+    add_column "currencies", "symbol", :string, default: "€"
   end
 
   def self.down
diff --git a/activerecord/test/migrations/missing/1000_people_have_middle_names.rb b/activerecord/test/migrations/missing/1000_people_have_middle_names.rb
index e046944e31..d3c9b127fb 100644
--- a/activerecord/test/migrations/missing/1000_people_have_middle_names.rb
+++ b/activerecord/test/migrations/missing/1000_people_have_middle_names.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class PeopleHaveMiddleNames < ActiveRecord::Migration::Current
   def self.up
     add_column "people", "middle_name", :string
diff --git a/activerecord/test/migrations/missing/1_people_have_last_names.rb b/activerecord/test/migrations/missing/1_people_have_last_names.rb
index 50fe2a9c8e..bd5f5ea11e 100644
--- a/activerecord/test/migrations/missing/1_people_have_last_names.rb
+++ b/activerecord/test/migrations/missing/1_people_have_last_names.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class PeopleHaveLastNames < ActiveRecord::Migration::Current
   def self.up
     add_column "people", "last_name", :string
diff --git a/activerecord/test/migrations/missing/3_we_need_reminders.rb b/activerecord/test/migrations/missing/3_we_need_reminders.rb
index d7c63ac892..4647268c6e 100644
--- a/activerecord/test/migrations/missing/3_we_need_reminders.rb
+++ b/activerecord/test/migrations/missing/3_we_need_reminders.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class WeNeedReminders < ActiveRecord::Migration::Current
   def self.up
     create_table("reminders") do |t|
diff --git a/activerecord/test/migrations/missing/4_innocent_jointable.rb b/activerecord/test/migrations/missing/4_innocent_jointable.rb
index 20fe183777..8063bc0558 100644
--- a/activerecord/test/migrations/missing/4_innocent_jointable.rb
+++ b/activerecord/test/migrations/missing/4_innocent_jointable.rb
@@ -1,6 +1,8 @@
+# frozen_string_literal: true
+
 class InnocentJointable < ActiveRecord::Migration::Current
   def self.up
-    create_table("people_reminders", :id => false) do |t|
+    create_table("people_reminders", id: false) do |t|
       t.column :reminder_id, :integer
       t.column :person_id, :integer
     end
diff --git a/activerecord/test/migrations/rename/1_we_need_things.rb b/activerecord/test/migrations/rename/1_we_need_things.rb
index 9dce01acfd..8e71a1d996 100644
--- a/activerecord/test/migrations/rename/1_we_need_things.rb
+++ b/activerecord/test/migrations/rename/1_we_need_things.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class WeNeedThings < ActiveRecord::Migration::Current
   def self.up
     create_table("things") do |t|
diff --git a/activerecord/test/migrations/rename/2_rename_things.rb b/activerecord/test/migrations/rename/2_rename_things.rb
index cb8484e7dc..110fe3f0fa 100644
--- a/activerecord/test/migrations/rename/2_rename_things.rb
+++ b/activerecord/test/migrations/rename/2_rename_things.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class RenameThings < ActiveRecord::Migration::Current
   def self.up
     rename_table "things", "awesome_things"
diff --git a/activerecord/test/migrations/to_copy/1_people_have_hobbies.rb b/activerecord/test/migrations/to_copy/1_people_have_hobbies.rb
index 76734bcd7d..badccf65cc 100644
--- a/activerecord/test/migrations/to_copy/1_people_have_hobbies.rb
+++ b/activerecord/test/migrations/to_copy/1_people_have_hobbies.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class PeopleHaveHobbies < ActiveRecord::Migration::Current
   def self.up
     add_column "people", "hobbies", :text
diff --git a/activerecord/test/migrations/to_copy/2_people_have_descriptions.rb b/activerecord/test/migrations/to_copy/2_people_have_descriptions.rb
index 7f883dbb45..1d19d5d6f4 100644
--- a/activerecord/test/migrations/to_copy/2_people_have_descriptions.rb
+++ b/activerecord/test/migrations/to_copy/2_people_have_descriptions.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class PeopleHaveDescriptions < ActiveRecord::Migration::Current
   def self.up
     add_column "people", "description", :text
diff --git a/activerecord/test/migrations/to_copy2/1_create_articles.rb b/activerecord/test/migrations/to_copy2/1_create_articles.rb
index 2e9f5ec6bc..85c166b319 100644
--- a/activerecord/test/migrations/to_copy2/1_create_articles.rb
+++ b/activerecord/test/migrations/to_copy2/1_create_articles.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class CreateArticles < ActiveRecord::Migration::Current
   def self.up
   end
diff --git a/activerecord/test/migrations/to_copy2/2_create_comments.rb b/activerecord/test/migrations/to_copy2/2_create_comments.rb
index d361847d4b..1d213a1705 100644
--- a/activerecord/test/migrations/to_copy2/2_create_comments.rb
+++ b/activerecord/test/migrations/to_copy2/2_create_comments.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class CreateComments < ActiveRecord::Migration::Current
   def self.up
   end
diff --git a/activerecord/test/migrations/to_copy_with_name_collision/1_people_have_hobbies.rb b/activerecord/test/migrations/to_copy_with_name_collision/1_people_have_hobbies.rb
index 1a863367dd..d9fef596f5 100644
--- a/activerecord/test/migrations/to_copy_with_name_collision/1_people_have_hobbies.rb
+++ b/activerecord/test/migrations/to_copy_with_name_collision/1_people_have_hobbies.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class PeopleHaveHobbies < ActiveRecord::Migration::Current
   def self.up
     add_column "people", "hobbies", :string
diff --git a/activerecord/test/migrations/to_copy_with_timestamps/20090101010101_people_have_hobbies.rb b/activerecord/test/migrations/to_copy_with_timestamps/20090101010101_people_have_hobbies.rb
index 76734bcd7d..badccf65cc 100644
--- a/activerecord/test/migrations/to_copy_with_timestamps/20090101010101_people_have_hobbies.rb
+++ b/activerecord/test/migrations/to_copy_with_timestamps/20090101010101_people_have_hobbies.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class PeopleHaveHobbies < ActiveRecord::Migration::Current
   def self.up
     add_column "people", "hobbies", :text
diff --git a/activerecord/test/migrations/to_copy_with_timestamps/20090101010202_people_have_descriptions.rb b/activerecord/test/migrations/to_copy_with_timestamps/20090101010202_people_have_descriptions.rb
index 7f883dbb45..1d19d5d6f4 100644
--- a/activerecord/test/migrations/to_copy_with_timestamps/20090101010202_people_have_descriptions.rb
+++ b/activerecord/test/migrations/to_copy_with_timestamps/20090101010202_people_have_descriptions.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class PeopleHaveDescriptions < ActiveRecord::Migration::Current
   def self.up
     add_column "people", "description", :text
diff --git a/activerecord/test/migrations/to_copy_with_timestamps2/20090101010101_create_articles.rb b/activerecord/test/migrations/to_copy_with_timestamps2/20090101010101_create_articles.rb
index 2e9f5ec6bc..85c166b319 100644
--- a/activerecord/test/migrations/to_copy_with_timestamps2/20090101010101_create_articles.rb
+++ b/activerecord/test/migrations/to_copy_with_timestamps2/20090101010101_create_articles.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class CreateArticles < ActiveRecord::Migration::Current
   def self.up
   end
diff --git a/activerecord/test/migrations/to_copy_with_timestamps2/20090101010202_create_comments.rb b/activerecord/test/migrations/to_copy_with_timestamps2/20090101010202_create_comments.rb
index d361847d4b..1d213a1705 100644
--- a/activerecord/test/migrations/to_copy_with_timestamps2/20090101010202_create_comments.rb
+++ b/activerecord/test/migrations/to_copy_with_timestamps2/20090101010202_create_comments.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class CreateComments < ActiveRecord::Migration::Current
   def self.up
   end
diff --git a/activerecord/test/migrations/valid/1_valid_people_have_last_names.rb b/activerecord/test/migrations/valid/1_valid_people_have_last_names.rb
index c450211d8c..3bedcdcdf0 100644
--- a/activerecord/test/migrations/valid/1_valid_people_have_last_names.rb
+++ b/activerecord/test/migrations/valid/1_valid_people_have_last_names.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class ValidPeopleHaveLastNames < ActiveRecord::Migration::Current
   def self.up
     add_column "people", "last_name", :string
diff --git a/activerecord/test/migrations/valid/2_we_need_reminders.rb b/activerecord/test/migrations/valid/2_we_need_reminders.rb
index d7c63ac892..4647268c6e 100644
--- a/activerecord/test/migrations/valid/2_we_need_reminders.rb
+++ b/activerecord/test/migrations/valid/2_we_need_reminders.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class WeNeedReminders < ActiveRecord::Migration::Current
   def self.up
     create_table("reminders") do |t|
diff --git a/activerecord/test/migrations/valid/3_innocent_jointable.rb b/activerecord/test/migrations/valid/3_innocent_jointable.rb
index 20fe183777..8063bc0558 100644
--- a/activerecord/test/migrations/valid/3_innocent_jointable.rb
+++ b/activerecord/test/migrations/valid/3_innocent_jointable.rb
@@ -1,6 +1,8 @@
+# frozen_string_literal: true
+
 class InnocentJointable < ActiveRecord::Migration::Current
   def self.up
-    create_table("people_reminders", :id => false) do |t|
+    create_table("people_reminders", id: false) do |t|
       t.column :reminder_id, :integer
       t.column :person_id, :integer
     end
diff --git a/activerecord/test/migrations/valid_with_subdirectories/1_valid_people_have_last_names.rb b/activerecord/test/migrations/valid_with_subdirectories/1_valid_people_have_last_names.rb
index c450211d8c..3bedcdcdf0 100644
--- a/activerecord/test/migrations/valid_with_subdirectories/1_valid_people_have_last_names.rb
+++ b/activerecord/test/migrations/valid_with_subdirectories/1_valid_people_have_last_names.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class ValidPeopleHaveLastNames < ActiveRecord::Migration::Current
   def self.up
     add_column "people", "last_name", :string
diff --git a/activerecord/test/migrations/valid_with_subdirectories/sub/2_we_need_reminders.rb b/activerecord/test/migrations/valid_with_subdirectories/sub/2_we_need_reminders.rb
index d7c63ac892..4647268c6e 100644
--- a/activerecord/test/migrations/valid_with_subdirectories/sub/2_we_need_reminders.rb
+++ b/activerecord/test/migrations/valid_with_subdirectories/sub/2_we_need_reminders.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class WeNeedReminders < ActiveRecord::Migration::Current
   def self.up
     create_table("reminders") do |t|
diff --git a/activerecord/test/migrations/valid_with_subdirectories/sub1/3_innocent_jointable.rb b/activerecord/test/migrations/valid_with_subdirectories/sub1/3_innocent_jointable.rb
index 20fe183777..8063bc0558 100644
--- a/activerecord/test/migrations/valid_with_subdirectories/sub1/3_innocent_jointable.rb
+++ b/activerecord/test/migrations/valid_with_subdirectories/sub1/3_innocent_jointable.rb
@@ -1,6 +1,8 @@
+# frozen_string_literal: true
+
 class InnocentJointable < ActiveRecord::Migration::Current
   def self.up
-    create_table("people_reminders", :id => false) do |t|
+    create_table("people_reminders", id: false) do |t|
       t.column :reminder_id, :integer
       t.column :person_id, :integer
     end
diff --git a/activerecord/test/migrations/valid_with_timestamps/20100101010101_valid_with_timestamps_people_have_last_names.rb b/activerecord/test/migrations/valid_with_timestamps/20100101010101_valid_with_timestamps_people_have_last_names.rb
index 9fd27593f0..b938847170 100644
--- a/activerecord/test/migrations/valid_with_timestamps/20100101010101_valid_with_timestamps_people_have_last_names.rb
+++ b/activerecord/test/migrations/valid_with_timestamps/20100101010101_valid_with_timestamps_people_have_last_names.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class ValidWithTimestampsPeopleHaveLastNames < ActiveRecord::Migration::Current
   def self.up
     add_column "people", "last_name", :string
diff --git a/activerecord/test/migrations/valid_with_timestamps/20100201010101_valid_with_timestamps_we_need_reminders.rb b/activerecord/test/migrations/valid_with_timestamps/20100201010101_valid_with_timestamps_we_need_reminders.rb
index 4a59921136..94551e8208 100644
--- a/activerecord/test/migrations/valid_with_timestamps/20100201010101_valid_with_timestamps_we_need_reminders.rb
+++ b/activerecord/test/migrations/valid_with_timestamps/20100201010101_valid_with_timestamps_we_need_reminders.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class ValidWithTimestampsWeNeedReminders < ActiveRecord::Migration::Current
   def self.up
     create_table("reminders") do |t|
diff --git a/activerecord/test/migrations/valid_with_timestamps/20100301010101_valid_with_timestamps_innocent_jointable.rb b/activerecord/test/migrations/valid_with_timestamps/20100301010101_valid_with_timestamps_innocent_jointable.rb
index bf934576c9..672edc5253 100644
--- a/activerecord/test/migrations/valid_with_timestamps/20100301010101_valid_with_timestamps_innocent_jointable.rb
+++ b/activerecord/test/migrations/valid_with_timestamps/20100301010101_valid_with_timestamps_innocent_jointable.rb
@@ -1,6 +1,8 @@
+# frozen_string_literal: true
+
 class ValidWithTimestampsInnocentJointable < ActiveRecord::Migration::Current
   def self.up
-    create_table("people_reminders", :id => false) do |t|
+    create_table("people_reminders", id: false) do |t|
       t.column :reminder_id, :integer
       t.column :person_id, :integer
     end
diff --git a/activerecord/test/migrations/version_check/20131219224947_migration_version_check.rb b/activerecord/test/migrations/version_check/20131219224947_migration_version_check.rb
index 6f314c881c..91bfbbdfd1 100644
--- a/activerecord/test/migrations/version_check/20131219224947_migration_version_check.rb
+++ b/activerecord/test/migrations/version_check/20131219224947_migration_version_check.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class MigrationVersionCheck < ActiveRecord::Migration::Current
   def self.up
     raise "incorrect migration version" unless version == 20131219224947
diff --git a/activerecord/test/models/account.rb b/activerecord/test/models/account.rb
new file mode 100644
index 0000000000..0c3cd45a81
--- /dev/null
+++ b/activerecord/test/models/account.rb
@@ -0,0 +1,34 @@
+# frozen_string_literal: true
+
+class Account < ActiveRecord::Base
+  belongs_to :firm, class_name: "Company"
+  belongs_to :unautosaved_firm, foreign_key: "firm_id", class_name: "Firm", autosave: false
+
+  alias_attribute :available_credit, :credit_limit
+
+  def self.destroyed_account_ids
+    @destroyed_account_ids ||= Hash.new { |h, k| h[k] = [] }
+  end
+
+  # Test private kernel method through collection proxy using has_many.
+  def self.open
+    where("firm_name = ?", "37signals")
+  end
+
+  before_destroy do |account|
+    if account.firm
+      Account.destroyed_account_ids[account.firm.id] << account.id
+    end
+  end
+
+  validate :check_empty_credit_limit
+
+  private
+    def check_empty_credit_limit
+      errors.add("credit_limit", :blank) if credit_limit.blank?
+    end
+
+    def private_method
+      "Sir, yes sir!"
+    end
+end
diff --git a/activerecord/test/models/admin.rb b/activerecord/test/models/admin.rb
index a38e3f4846..a40b5a33b2 100644
--- a/activerecord/test/models/admin.rb
+++ b/activerecord/test/models/admin.rb
@@ -1,5 +1,7 @@
+# frozen_string_literal: true
+
 module Admin
   def self.table_name_prefix
-    'admin_'
+    "admin_"
   end
 end
diff --git a/activerecord/test/models/admin/account.rb b/activerecord/test/models/admin/account.rb
index bd23192d20..41fe2d782b 100644
--- a/activerecord/test/models/admin/account.rb
+++ b/activerecord/test/models/admin/account.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Admin::Account < ActiveRecord::Base
   has_many :users
 end
diff --git a/activerecord/test/models/admin/randomly_named_c1.rb b/activerecord/test/models/admin/randomly_named_c1.rb
index b64ae7fc41..d89b8dd293 100644
--- a/activerecord/test/models/admin/randomly_named_c1.rb
+++ b/activerecord/test/models/admin/randomly_named_c1.rb
@@ -1,7 +1,9 @@
-class Admin::ClassNameThatDoesNotFollowCONVENTIONS1 < ActiveRecord::Base

-  self.table_name = :randomly_named_table2

-end

-

-class Admin::ClassNameThatDoesNotFollowCONVENTIONS2 < ActiveRecord::Base

-  self.table_name = :randomly_named_table3

-end

+# frozen_string_literal: true
+
+class Admin::ClassNameThatDoesNotFollowCONVENTIONS1 < ActiveRecord::Base
+  self.table_name = :randomly_named_table2
+end
+
+class Admin::ClassNameThatDoesNotFollowCONVENTIONS2 < ActiveRecord::Base
+  self.table_name = :randomly_named_table3
+end
diff --git a/activerecord/test/models/admin/user.rb b/activerecord/test/models/admin/user.rb
index 48a110bd23..abb5cb28e7 100644
--- a/activerecord/test/models/admin/user.rb
+++ b/activerecord/test/models/admin/user.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Admin::User < ActiveRecord::Base
   class Coder
     def initialize(default = {})
@@ -15,26 +17,26 @@ class Admin::User < ActiveRecord::Base
 
   belongs_to :account
   store :params, accessors: [ :token ], coder: YAML
-  store :settings, :accessors => [ :color, :homepage ]
+  store :settings, accessors: [ :color, :homepage ]
   store_accessor :settings, :favorite_food
-  store :preferences, :accessors => [ :remember_login ]
-  store :json_data, :accessors => [ :height, :weight ], :coder => Coder.new
-  store :json_data_empty, :accessors => [ :is_a_good_guy ], :coder => Coder.new
+  store :preferences, accessors: [ :remember_login ]
+  store :json_data, accessors: [ :height, :weight ], coder: Coder.new
+  store :json_data_empty, accessors: [ :is_a_good_guy ], coder: Coder.new
 
   def phone_number
-    read_store_attribute(:settings, :phone_number).gsub(/(\d{3})(\d{3})(\d{4})/,'(\1) \2-\3')
+    read_store_attribute(:settings, :phone_number).gsub(/(\d{3})(\d{3})(\d{4})/, '(\1) \2-\3')
   end
 
   def phone_number=(value)
-    write_store_attribute(:settings, :phone_number, value && value.gsub(/[^\d]/,''))
+    write_store_attribute(:settings, :phone_number, value && value.gsub(/[^\d]/, ""))
   end
 
   def color
-    super || 'red'
+    super || "red"
   end
 
   def color=(value)
-    value = 'blue' unless %w(black red green blue).include?(value)
+    value = "blue" unless %w(black red green blue).include?(value)
     super
   end
 end
diff --git a/activerecord/test/models/aircraft.rb b/activerecord/test/models/aircraft.rb
index c4404a8094..4fdea46cf7 100644
--- a/activerecord/test/models/aircraft.rb
+++ b/activerecord/test/models/aircraft.rb
@@ -1,5 +1,7 @@
+# frozen_string_literal: true
+
 class Aircraft < ActiveRecord::Base
   self.pluralize_table_names = false
-  has_many :engines, :foreign_key => "car_id"
+  has_many :engines, foreign_key: "car_id"
   has_many :wheels, as: :wheelable
 end
diff --git a/activerecord/test/models/arunit2_model.rb b/activerecord/test/models/arunit2_model.rb
index 04b8b15d3d..5b0da8a249 100644
--- a/activerecord/test/models/arunit2_model.rb
+++ b/activerecord/test/models/arunit2_model.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class ARUnit2Model < ActiveRecord::Base
   self.abstract_class = true
 end
diff --git a/activerecord/test/models/author.rb b/activerecord/test/models/author.rb
index 38b983eda0..cb8686f315 100644
--- a/activerecord/test/models/author.rb
+++ b/activerecord/test/models/author.rb
@@ -1,146 +1,152 @@
+# frozen_string_literal: true
+
 class Author < ActiveRecord::Base
   has_many :posts
   has_many :serialized_posts
   has_one :post
-  has_many :very_special_comments, :through => :posts
-  has_many :posts_with_comments, -> { includes(:comments) }, :class_name => "Post"
-  has_many :popular_grouped_posts, -> { includes(:comments).group("type").having("SUM(comments_count) > 1").select("type") }, :class_name => "Post"
-  has_many :posts_with_comments_sorted_by_comment_id, -> { includes(:comments).order('comments.id') }, :class_name => "Post"
-  has_many :posts_sorted_by_id_limited, -> { order('posts.id').limit(1) }, :class_name => "Post"
-  has_many :posts_with_categories, -> { includes(:categories) }, :class_name => "Post"
-  has_many :posts_with_comments_and_categories, -> { includes(:comments, :categories).order("posts.id") }, :class_name => "Post"
-  has_many :posts_with_special_categorizations, :class_name => 'PostWithSpecialCategorization'
-  has_one  :post_about_thinking, -> { where("posts.title like '%thinking%'") }, :class_name => 'Post'
-  has_one  :post_about_thinking_with_last_comment, -> { where("posts.title like '%thinking%'").includes(:last_comment) }, :class_name => 'Post'
+  has_many :very_special_comments, through: :posts
+  has_many :posts_with_comments, -> { includes(:comments) }, class_name: "Post"
+  has_many :popular_grouped_posts, -> { includes(:comments).group("type").having("SUM(comments_count) > 1").select("type") }, class_name: "Post"
+  has_many :posts_with_comments_sorted_by_comment_id, -> { includes(:comments).order("comments.id") }, class_name: "Post"
+  has_many :posts_sorted_by_id_limited, -> { order("posts.id").limit(1) }, class_name: "Post"
+  has_many :posts_with_categories, -> { includes(:categories) }, class_name: "Post"
+  has_many :posts_with_comments_and_categories, -> { includes(:comments, :categories).order("posts.id") }, class_name: "Post"
+  has_many :posts_with_special_categorizations, class_name: "PostWithSpecialCategorization"
+  has_one  :post_about_thinking, -> { where("posts.title like '%thinking%'") }, class_name: "Post"
+  has_one  :post_about_thinking_with_last_comment, -> { where("posts.title like '%thinking%'").includes(:last_comment) }, class_name: "Post"
   has_many :comments, through: :posts do
     def ratings
       Rating.joins(:comment).merge(self)
     end
   end
-  has_many :comments_containing_the_letter_e, :through => :posts, :source => :comments
-  has_many :comments_with_order_and_conditions, -> { order('comments.body').where("comments.body like 'Thank%'") }, :through => :posts, :source => :comments
-  has_many :comments_with_include, -> { includes(:post) }, :through => :posts, :source => :comments
+  has_many :comments_containing_the_letter_e, through: :posts, source: :comments
+  has_many :comments_with_order_and_conditions, -> { order("comments.body").where("comments.body like 'Thank%'") }, through: :posts, source: :comments
+  has_many :comments_with_include, -> { includes(:post).where(posts: { type: "Post" }) }, through: :posts, source: :comments
+  has_many :comments_for_first_author, -> { for_first_author }, through: :posts, source: :comments
 
   has_many :first_posts
-  has_many :comments_on_first_posts, -> { order('posts.id desc, comments.id asc') }, :through => :first_posts, :source => :comments
+  has_many :comments_on_first_posts, -> { order("posts.id desc, comments.id asc") }, through: :first_posts, source: :comments
 
   has_one :first_post
-  has_one :comment_on_first_post, -> { order('posts.id desc, comments.id asc') }, :through => :first_post, :source => :comments
+  has_one :comment_on_first_post, -> { order("posts.id desc, comments.id asc") }, through: :first_post, source: :comments
 
-  has_many :thinking_posts, -> { where(:title => 'So I was thinking') }, :dependent => :delete_all, :class_name => 'Post'
-  has_many :welcome_posts, -> { where(:title => 'Welcome to the weblog') }, :class_name => 'Post'
+  has_many :thinking_posts, -> { where(title: "So I was thinking") }, dependent: :delete_all, class_name: "Post"
+  has_many :welcome_posts, -> { where(title: "Welcome to the weblog") }, class_name: "Post"
 
   has_many :welcome_posts_with_one_comment,
-           -> { where(title: 'Welcome to the weblog').where('comments_count = ?', 1) },
-           class_name: 'Post'
+           -> { where(title: "Welcome to the weblog").where("comments_count = ?", 1) },
+           class_name: "Post"
   has_many :welcome_posts_with_comments,
-           -> { where(title: 'Welcome to the weblog').where(Post.arel_table[:comments_count].gt(0)) },
-           class_name: 'Post'
+           -> { where(title: "Welcome to the weblog").where(Post.arel_table[:comments_count].gt(0)) },
+           class_name: "Post"
 
-  has_many :comments_desc, -> { order('comments.id DESC') }, :through => :posts, :source => :comments
-  has_many :funky_comments, :through => :posts, :source => :comments
-  has_many :ordered_uniq_comments, -> { distinct.order('comments.id') }, :through => :posts, :source => :comments
-  has_many :ordered_uniq_comments_desc, -> { distinct.order('comments.id DESC') }, :through => :posts, :source => :comments
-  has_many :readonly_comments, -> { readonly }, :through => :posts, :source => :comments
+  has_many :comments_desc, -> { order("comments.id DESC") }, through: :posts, source: :comments
+  has_many :unordered_comments, -> { unscope(:order).distinct }, through: :posts_sorted_by_id_limited, source: :comments
+  has_many :funky_comments, through: :posts, source: :comments
+  has_many :ordered_uniq_comments, -> { distinct.order("comments.id") }, through: :posts, source: :comments
+  has_many :ordered_uniq_comments_desc, -> { distinct.order("comments.id DESC") }, through: :posts, source: :comments
+  has_many :readonly_comments, -> { readonly }, through: :posts, source: :comments
 
   has_many :special_posts
-  has_many :special_post_comments, :through => :special_posts, :source => :comments
-  has_many :special_posts_with_default_scope, :class_name => 'SpecialPostWithDefaultScope'
-
-  has_many :sti_posts, :class_name => 'StiPost'
-  has_many :sti_post_comments, :through => :sti_posts, :source => :comments
-
-  has_many :special_nonexistent_posts, -> { where("posts.body = 'nonexistent'") }, :class_name => "SpecialPost"
-  has_many :special_nonexistent_post_comments, -> { where('comments.post_id' => 0) }, :through => :special_nonexistent_posts, :source => :comments
-  has_many :nonexistent_comments, :through => :posts
-
-  has_many :hello_posts, -> { where "posts.body = 'hello'" }, :class_name => "Post"
-  has_many :hello_post_comments, :through => :hello_posts, :source => :comments
-  has_many :posts_with_no_comments, -> { where('comments.id' => nil).includes(:comments) }, :class_name => 'Post'
-
-  has_many :hello_posts_with_hash_conditions, -> { where(:body => 'hello') }, :class_name => "Post"
-  has_many :hello_post_comments_with_hash_conditions, :through =>
-:hello_posts_with_hash_conditions, :source => :comments
-
-  has_many :other_posts,          :class_name => "Post"
-  has_many :posts_with_callbacks, :class_name => "Post", :before_add => :log_before_adding,
-           :after_add     => :log_after_adding,
-           :before_remove => :log_before_removing,
-           :after_remove  => :log_after_removing
-  has_many :posts_with_proc_callbacks, :class_name => "Post",
-           :before_add    => Proc.new {|o, r| o.post_log << "before_adding#{r.id || '<new>'}"},
-           :after_add     => Proc.new {|o, r| o.post_log << "after_adding#{r.id || '<new>'}"},
-           :before_remove => Proc.new {|o, r| o.post_log << "before_removing#{r.id}"},
-           :after_remove  => Proc.new {|o, r| o.post_log << "after_removing#{r.id}"}
-  has_many :posts_with_multiple_callbacks, :class_name => "Post",
-           :before_add => [:log_before_adding, Proc.new {|o, r| o.post_log << "before_adding_proc#{r.id || '<new>'}"}],
-           :after_add  => [:log_after_adding,  Proc.new {|o, r| o.post_log << "after_adding_proc#{r.id || '<new>'}"}]
-  has_many :unchangeable_posts, :class_name => "Post", :before_add => :raise_exception, :after_add => :log_after_adding
-
-  has_many :categorizations
-  has_many :categories, :through => :categorizations
-  has_many :named_categories, :through => :categorizations
+  has_many :special_post_comments, through: :special_posts, source: :comments
+  has_many :special_posts_with_default_scope, class_name: "SpecialPostWithDefaultScope"
+
+  has_many :sti_posts, class_name: "StiPost"
+  has_many :sti_post_comments, through: :sti_posts, source: :comments
+
+  has_many :special_nonexistent_posts, -> { where("posts.body = 'nonexistent'") }, class_name: "SpecialPost"
+  has_many :special_nonexistent_post_comments, -> { where("comments.post_id" => 0) }, through: :special_nonexistent_posts, source: :comments
+  has_many :nonexistent_comments, through: :posts
+
+  has_many :hello_posts, -> { where "posts.body = 'hello'" }, class_name: "Post"
+  has_many :hello_post_comments, through: :hello_posts, source: :comments
+  has_many :posts_with_no_comments, -> { where("comments.id" => nil).includes(:comments) }, class_name: "Post"
+
+  has_many :hello_posts_with_hash_conditions, -> { where(body: "hello") }, class_name: "Post"
+  has_many :hello_post_comments_with_hash_conditions, through: :hello_posts_with_hash_conditions, source: :comments
+
+  has_many :other_posts,          class_name: "Post"
+  has_many :posts_with_callbacks, class_name: "Post", before_add: :log_before_adding,
+           after_add: :log_after_adding,
+           before_remove: :log_before_removing,
+           after_remove: :log_after_removing
+  has_many :posts_with_proc_callbacks, class_name: "Post",
+           before_add: Proc.new { |o, r| o.post_log << "before_adding#{r.id || '<new>'}" },
+           after_add: Proc.new { |o, r| o.post_log << "after_adding#{r.id || '<new>'}" },
+           before_remove: Proc.new { |o, r| o.post_log << "before_removing#{r.id}" },
+           after_remove: Proc.new { |o, r| o.post_log << "after_removing#{r.id}" }
+  has_many :posts_with_multiple_callbacks, class_name: "Post",
+           before_add: [:log_before_adding, Proc.new { |o, r| o.post_log << "before_adding_proc#{r.id || '<new>'}" }],
+           after_add: [:log_after_adding,  Proc.new { |o, r| o.post_log << "after_adding_proc#{r.id || '<new>'}" }]
+  has_many :unchangeable_posts, class_name: "Post", before_add: :raise_exception, after_add: :log_after_adding
+
+  has_many :categorizations, -> {}
+  has_many :categories, through: :categorizations
+  has_many :named_categories, through: :categorizations
 
   has_many :special_categorizations
-  has_many :special_categories, :through => :special_categorizations, :source => :category
-  has_one  :special_category,   :through => :special_categorizations, :source => :category
+  has_many :special_categories, through: :special_categorizations, source: :category
+  has_one  :special_category,   through: :special_categorizations, source: :category
 
-  has_many :categories_like_general, -> { where(:name => 'General') }, :through => :categorizations, :source => :category, :class_name => 'Category'
+  has_many :categories_like_general, -> { where(name: "General") }, through: :categorizations, source: :category, class_name: "Category"
 
-  has_many :categorized_posts, :through => :categorizations, :source => :post
-  has_many :unique_categorized_posts, -> { distinct }, :through => :categorizations, :source => :post
+  has_many :categorized_posts, through: :categorizations, source: :post
+  has_many :unique_categorized_posts, -> { distinct }, through: :categorizations, source: :post
 
-  has_many :nothings, :through => :kateggorisatons, :class_name => 'Category'
+  has_many :nothings, through: :kateggorisatons, class_name: "Category"
 
   has_many :author_favorites
-  has_many :favorite_authors, -> { order('name') }, :through => :author_favorites
+  has_many :favorite_authors, -> { order("name") }, through: :author_favorites
 
-  has_many :taggings,        :through => :posts, :source => :taggings
-  has_many :taggings_2,      :through => :posts, :source => :tagging
-  has_many :tags,            :through => :posts
-  has_many :post_categories, :through => :posts, :source => :categories
-  has_many :tagging_tags,    :through => :taggings, :source => :tag
+  has_many :taggings,        through: :posts, source: :taggings
+  has_many :taggings_2,      through: :posts, source: :tagging
+  has_many :tags,            through: :posts
+  has_many :ordered_tags,    through: :posts
+  has_many :post_categories, through: :posts, source: :categories
+  has_many :tagging_tags,    through: :taggings, source: :tag
 
-  has_many :similar_posts, -> { distinct }, :through => :tags, :source => :tagged_posts
-  has_many :distinct_tags, -> { select("DISTINCT tags.*").order("tags.name") }, :through => :posts, :source => :tags
+  has_many :similar_posts, -> { distinct }, through: :tags, source: :tagged_posts
+  has_many :ordered_posts, -> { distinct }, through: :ordered_tags, source: :tagged_posts
+  has_many :distinct_tags, -> { select("DISTINCT tags.*").order("tags.name") }, through: :posts, source: :tags
 
-  has_many :tags_with_primary_key, :through => :posts
+  has_many :tags_with_primary_key, through: :posts
 
   has_many :books
-  has_many :subscriptions,        :through => :books
-  has_many :subscribers, -> { order("subscribers.nick") }, :through => :subscriptions
-  has_many :distinct_subscribers, -> { select("DISTINCT subscribers.*").order("subscribers.nick") }, :through => :subscriptions, :source => :subscriber
+  has_many :unpublished_books, -> { where(status: [:proposed, :written]) }, class_name: "Book"
+  has_many :subscriptions,        through: :books
+  has_many :subscribers, -> { order("subscribers.nick") }, through: :subscriptions
+  has_many :distinct_subscribers, -> { select("DISTINCT subscribers.*").order("subscribers.nick") }, through: :subscriptions, source: :subscriber
 
-  has_one :essay, :primary_key => :name, :as => :writer
-  has_one :essay_category, :through => :essay, :source => :category
-  has_one :essay_owner, :through => :essay, :source => :owner
+  has_one :essay, primary_key: :name, as: :writer
+  has_one :essay_category, through: :essay, source: :category
+  has_one :essay_owner, through: :essay, source: :owner
 
-  has_one :essay_2, :primary_key => :name, :class_name => 'Essay', :foreign_key => :author_id
-  has_one :essay_category_2, :through => :essay_2, :source => :category
+  has_one :essay_2, primary_key: :name, class_name: "Essay", foreign_key: :author_id
+  has_one :essay_category_2, through: :essay_2, source: :category
 
-  has_many :essays, :primary_key => :name, :as => :writer
-  has_many :essay_categories, :through => :essays, :source => :category
-  has_many :essay_owners, :through => :essays, :source => :owner
+  has_many :essays, primary_key: :name, as: :writer
+  has_many :essay_categories, through: :essays, source: :category
+  has_many :essay_owners, through: :essays, source: :owner
 
-  has_many :essays_2, :primary_key => :name, :class_name => 'Essay', :foreign_key => :author_id
-  has_many :essay_categories_2, :through => :essays_2, :source => :category
+  has_many :essays_2, primary_key: :name, class_name: "Essay", foreign_key: :author_id
+  has_many :essay_categories_2, through: :essays_2, source: :category
 
-  belongs_to :owned_essay, :primary_key => :name, :class_name => 'Essay'
-  has_one :owned_essay_category, :through => :owned_essay, :source => :category
+  belongs_to :owned_essay, primary_key: :name, class_name: "Essay"
+  has_one :owned_essay_category, through: :owned_essay, source: :category
 
-  belongs_to :author_address,       :dependent => :destroy
-  belongs_to :author_address_extra, :dependent => :delete, :class_name => "AuthorAddress"
+  belongs_to :author_address,       dependent: :destroy
+  belongs_to :author_address_extra, dependent: :delete, class_name: "AuthorAddress"
 
-  has_many :category_post_comments, :through => :categories, :source => :post_comments
+  has_many :category_post_comments, through: :categories, source: :post_comments
 
-  has_many :misc_posts, -> { where(:posts => { :title => ['misc post by bob', 'misc post by mary'] }) }, :class_name => 'Post'
-  has_many :misc_post_first_blue_tags, :through => :misc_posts, :source => :first_blue_tags
+  has_many :misc_posts, -> { where(posts: { title: ["misc post by bob", "misc post by mary"] }) }, class_name: "Post"
+  has_many :misc_post_first_blue_tags, through: :misc_posts, source: :first_blue_tags
 
-  has_many :misc_post_first_blue_tags_2, -> { where(:posts => { :title => ['misc post by bob', 'misc post by mary'] }) },
-           :through => :posts, :source => :first_blue_tags_2
+  has_many :misc_post_first_blue_tags_2, -> { where(posts: { title: ["misc post by bob", "misc post by mary"] }) },
+           through: :posts, source: :first_blue_tags_2
 
-  has_many :posts_with_default_include, :class_name => 'PostWithDefaultInclude'
-  has_many :comments_on_posts_with_default_include, :through => :posts_with_default_include, :source => :comments
+  has_many :posts_with_default_include, class_name: "PostWithDefaultInclude"
+  has_many :comments_on_posts_with_default_include, through: :posts_with_default_include, source: :comments
 
   has_many :posts_with_signature, ->(record) { where("posts.title LIKE ?", "%by #{record.name.downcase}%") }, class_name: "Post"
 
@@ -205,5 +211,5 @@ end
 
 class AuthorFavorite < ActiveRecord::Base
   belongs_to :author
-  belongs_to :favorite_author, :class_name => "Author"
+  belongs_to :favorite_author, class_name: "Author"
 end
diff --git a/activerecord/test/models/auto_id.rb b/activerecord/test/models/auto_id.rb
index 82c6544bd5..fd672603bb 100644
--- a/activerecord/test/models/auto_id.rb
+++ b/activerecord/test/models/auto_id.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class AutoId < ActiveRecord::Base
   self.table_name = "auto_id_tests"
   self.primary_key = "auto_id"
diff --git a/activerecord/test/models/autoloadable/extra_firm.rb b/activerecord/test/models/autoloadable/extra_firm.rb
index 5578ba0d9b..c46e34c101 100644
--- a/activerecord/test/models/autoloadable/extra_firm.rb
+++ b/activerecord/test/models/autoloadable/extra_firm.rb
@@ -1,2 +1,4 @@
+# frozen_string_literal: true
+
 class ExtraFirm < Company
 end
diff --git a/activerecord/test/models/binary.rb b/activerecord/test/models/binary.rb
index 39b2f5090a..b93f87519f 100644
--- a/activerecord/test/models/binary.rb
+++ b/activerecord/test/models/binary.rb
@@ -1,2 +1,4 @@
+# frozen_string_literal: true
+
 class Binary < ActiveRecord::Base
 end
diff --git a/activerecord/test/models/bird.rb b/activerecord/test/models/bird.rb
index 2a51d903b8..be08636ac6 100644
--- a/activerecord/test/models/bird.rb
+++ b/activerecord/test/models/bird.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Bird < ActiveRecord::Base
   belongs_to :pirate
   validates_presence_of :name
@@ -5,7 +7,7 @@ class Bird < ActiveRecord::Base
   accepts_nested_attributes_for :pirate
 
   attr_accessor :cancel_save_from_callback
-  before_save :cancel_save_callback_method, :if => :cancel_save_from_callback
+  before_save :cancel_save_callback_method, if: :cancel_save_from_callback
   def cancel_save_callback_method
     throw(:abort)
   end
diff --git a/activerecord/test/models/book.rb b/activerecord/test/models/book.rb
index e43e5c3901..afdda1a81e 100644
--- a/activerecord/test/models/book.rb
+++ b/activerecord/test/models/book.rb
@@ -1,20 +1,23 @@
+# frozen_string_literal: true
+
 class Book < ActiveRecord::Base
-  has_many :authors
+  belongs_to :author
 
-  has_many :citations, :foreign_key => 'book1_id'
+  has_many :citations, foreign_key: "book1_id"
   has_many :references, -> { distinct }, through: :citations, source: :reference_of
 
   has_many :subscriptions
   has_many :subscribers, through: :subscriptions
 
   enum status: [:proposed, :written, :published]
-  enum read_status: {unread: 0, reading: 2, read: 3}
+  enum read_status: { unread: 0, reading: 2, read: 3, forgotten: nil }
   enum nullable_status: [:single, :married]
   enum language: [:english, :spanish, :french], _prefix: :in
   enum author_visibility: [:visible, :invisible], _prefix: true
   enum illustrator_visibility: [:visible, :invisible], _prefix: true
   enum font_size: [:small, :medium, :large], _prefix: :with, _suffix: true
-  enum cover: { hard: 'hard', soft: 'soft' }
+  enum difficulty: [:easy, :medium, :hard], _suffix: :to_read
+  enum cover: { hard: "hard", soft: "soft" }
 
   def published!
     super
diff --git a/activerecord/test/models/boolean.rb b/activerecord/test/models/boolean.rb
index 7bae22e5f9..bee757fb9c 100644
--- a/activerecord/test/models/boolean.rb
+++ b/activerecord/test/models/boolean.rb
@@ -1,2 +1,7 @@
+# frozen_string_literal: true
+
 class Boolean < ActiveRecord::Base
+  def has_fun
+    super
+  end
 end
diff --git a/activerecord/test/models/bulb.rb b/activerecord/test/models/bulb.rb
index dc0296305a..ab92f7025d 100644
--- a/activerecord/test/models/bulb.rb
+++ b/activerecord/test/models/bulb.rb
@@ -1,6 +1,8 @@
+# frozen_string_literal: true
+
 class Bulb < ActiveRecord::Base
-  default_scope { where(:name => 'defaulty') }
-  belongs_to :car, :touch => true
+  default_scope { where(name: "defaulty") }
+  belongs_to :car, touch: true
   scope :awesome, -> { where(frickinawesome: true) }
 
   attr_reader :scope_after_initialize, :attributes_after_initialize
@@ -35,7 +37,7 @@ class CustomBulb < Bulb
   after_initialize :set_awesomeness
 
   def set_awesomeness
-    self.frickinawesome = true if name == 'Dude'
+    self.frickinawesome = true if name == "Dude"
   end
 end
 
@@ -50,9 +52,3 @@ class FailedBulb < Bulb
     throw(:abort)
   end
 end
-
-class TrickyBulb < Bulb
-  after_create do |record|
-    record.car.bulbs.to_a
-  end
-end
diff --git a/activerecord/test/models/cake_designer.rb b/activerecord/test/models/cake_designer.rb
index 9c57ef573a..0b2a00edfd 100644
--- a/activerecord/test/models/cake_designer.rb
+++ b/activerecord/test/models/cake_designer.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class CakeDesigner < ActiveRecord::Base
   has_one :chef, as: :employable
 end
diff --git a/activerecord/test/models/car.rb b/activerecord/test/models/car.rb
index 0f37e9a289..3d6a7a96c2 100644
--- a/activerecord/test/models/car.rb
+++ b/activerecord/test/models/car.rb
@@ -1,29 +1,31 @@
+# frozen_string_literal: true
+
 class Car < ActiveRecord::Base
   has_many :bulbs
   has_many :all_bulbs, -> { unscope where: :name }, class_name: "Bulb"
-  has_many :funky_bulbs, class_name: 'FunkyBulb', dependent: :destroy
-  has_many :failed_bulbs, class_name: 'FailedBulb', dependent: :destroy
-  has_many :foo_bulbs, -> { where(:name => 'foo') }, :class_name => "Bulb"
+  has_many :funky_bulbs, class_name: "FunkyBulb", dependent: :destroy
+  has_many :failed_bulbs, class_name: "FailedBulb", dependent: :destroy
+  has_many :foo_bulbs, -> { where(name: "foo") }, class_name: "Bulb"
   has_many :awesome_bulbs, -> { awesome }, class_name: "Bulb"
 
   has_one :bulb
 
   has_many :tyres
-  has_many :engines, :dependent => :destroy, inverse_of: :my_car
-  has_many :wheels, :as => :wheelable, :dependent => :destroy
+  has_many :engines, dependent: :destroy, inverse_of: :my_car
+  has_many :wheels, as: :wheelable, dependent: :destroy
 
-  has_many :price_estimates, :as => :estimate_of
+  has_many :price_estimates, as: :estimate_of
 
   scope :incl_tyres, -> { includes(:tyres) }
   scope :incl_engines, -> { includes(:engines) }
 
-  scope :order_using_new_style,  -> { order('name asc') }
+  scope :order_using_new_style,  -> { order("name asc") }
 end
 
 class CoolCar < Car
-  default_scope { order('name desc') }
+  default_scope { order("name desc") }
 end
 
 class FastCar < Car
-  default_scope { order('name desc') }
+  default_scope { order("name desc") }
 end
diff --git a/activerecord/test/models/carrier.rb b/activerecord/test/models/carrier.rb
index 230be118c3..995a9d3bef 100644
--- a/activerecord/test/models/carrier.rb
+++ b/activerecord/test/models/carrier.rb
@@ -1,2 +1,4 @@
+# frozen_string_literal: true
+
 class Carrier < ActiveRecord::Base
 end
diff --git a/activerecord/test/models/cat.rb b/activerecord/test/models/cat.rb
index dfdde18641..43013964b6 100644
--- a/activerecord/test/models/cat.rb
+++ b/activerecord/test/models/cat.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Cat < ActiveRecord::Base
   self.abstract_class = true
 
diff --git a/activerecord/test/models/categorization.rb b/activerecord/test/models/categorization.rb
index 4cd67c970a..68b0ea90d3 100644
--- a/activerecord/test/models/categorization.rb
+++ b/activerecord/test/models/categorization.rb
@@ -1,18 +1,20 @@
+# frozen_string_literal: true
+
 class Categorization < ActiveRecord::Base
   belongs_to :post
   belongs_to :category, counter_cache: true
-  belongs_to :named_category, :class_name => 'Category', :foreign_key => :named_category_name, :primary_key => :name
+  belongs_to :named_category, class_name: "Category", foreign_key: :named_category_name, primary_key: :name
   belongs_to :author
 
-  has_many :post_taggings, :through => :author, :source => :taggings
+  has_many :post_taggings, through: :author, source: :taggings
 
-  belongs_to :author_using_custom_pk,  :class_name => 'Author', :foreign_key => :author_id, :primary_key => :author_address_extra_id
-  has_many   :authors_using_custom_pk, :class_name => 'Author', :foreign_key => :id,        :primary_key => :category_id
+  belongs_to :author_using_custom_pk,  class_name: "Author", foreign_key: :author_id, primary_key: :author_address_extra_id
+  has_many   :authors_using_custom_pk, class_name: "Author", foreign_key: :id,        primary_key: :category_id
 end
 
 class SpecialCategorization < ActiveRecord::Base
-  self.table_name = 'categorizations'
-  default_scope { where(:special => true) }
+  self.table_name = "categorizations"
+  default_scope { where(special: true) }
 
   belongs_to :author
   belongs_to :category
diff --git a/activerecord/test/models/category.rb b/activerecord/test/models/category.rb
index 272223e1d8..2ccc00bed9 100644
--- a/activerecord/test/models/category.rb
+++ b/activerecord/test/models/category.rb
@@ -1,34 +1,45 @@
+# frozen_string_literal: true
+
 class Category < ActiveRecord::Base
   has_and_belongs_to_many :posts
-  has_and_belongs_to_many :special_posts, :class_name => "Post"
-  has_and_belongs_to_many :other_posts, :class_name => "Post"
-  has_and_belongs_to_many :posts_with_authors_sorted_by_author_id, -> { includes(:authors).order("authors.id") }, :class_name => "Post"
+  has_and_belongs_to_many :special_posts, class_name: "Post"
+  has_and_belongs_to_many :other_posts, class_name: "Post"
+  has_and_belongs_to_many :posts_with_authors_sorted_by_author_id, -> { includes(:authors).order("authors.id") }, class_name: "Post"
 
   has_and_belongs_to_many :select_testing_posts,
-                          -> { select 'posts.*, 1 as correctness_marker' },
-                          :class_name => 'Post',
-                          :foreign_key => 'category_id',
-                          :association_foreign_key => 'post_id'
+                          -> { select "posts.*, 1 as correctness_marker" },
+                          class_name: "Post",
+                          foreign_key: "category_id",
+                          association_foreign_key: "post_id"
 
   has_and_belongs_to_many :post_with_conditions,
-                          -> { where :title => 'Yet Another Testing Title' },
-                          :class_name => 'Post'
+                          -> { where title: "Yet Another Testing Title" },
+                          class_name: "Post"
 
-  has_and_belongs_to_many :popular_grouped_posts, -> { group("posts.type").having("sum(comments.post_id) > 2").includes(:comments) }, :class_name => "Post"
-  has_and_belongs_to_many :posts_grouped_by_title, -> { group("title").select("title") }, :class_name => "Post"
+  has_and_belongs_to_many :popular_grouped_posts, -> { group("posts.type").having("sum(comments.post_id) > 2").includes(:comments) }, class_name: "Post"
+  has_and_belongs_to_many :posts_grouped_by_title, -> { group("title").select("title") }, class_name: "Post"
 
   def self.what_are_you
-    'a category...'
+    "a category..."
   end
 
   has_many :categorizations
   has_many :special_categorizations
-  has_many :post_comments, :through => :posts, :source => :comments
+  has_many :post_comments, through: :posts, source: :comments
+
+  has_many :authors, through: :categorizations
+  has_many :authors_with_select, -> { select "authors.*, categorizations.post_id" }, through: :categorizations, source: :author
 
-  has_many :authors, :through => :categorizations
-  has_many :authors_with_select, -> { select 'authors.*, categorizations.post_id' }, :through => :categorizations, :source => :author
+  scope :general, -> { where(name: "General") }
 
-  scope :general, -> { where(:name => 'General') }
+  # Should be delegated `ast` and `locked` to `arel`.
+  def self.ast
+    raise
+  end
+
+  def self.locked
+    raise
+  end
 end
 
 class SpecialCategory < Category
diff --git a/activerecord/test/models/chef.rb b/activerecord/test/models/chef.rb
index 9d3dd01016..ff528644bc 100644
--- a/activerecord/test/models/chef.rb
+++ b/activerecord/test/models/chef.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Chef < ActiveRecord::Base
   belongs_to :employable, polymorphic: true
   has_many :recipes
diff --git a/activerecord/test/models/citation.rb b/activerecord/test/models/citation.rb
index 3d87eb795c..3d786f27eb 100644
--- a/activerecord/test/models/citation.rb
+++ b/activerecord/test/models/citation.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Citation < ActiveRecord::Base
-  belongs_to :reference_of, :class_name => "Book", :foreign_key => :book2_id
+  belongs_to :reference_of, class_name: "Book", foreign_key: :book2_id
 end
diff --git a/activerecord/test/models/club.rb b/activerecord/test/models/club.rb
index 6ceafe5858..2006e05fcf 100644
--- a/activerecord/test/models/club.rb
+++ b/activerecord/test/models/club.rb
@@ -1,23 +1,27 @@
+# frozen_string_literal: true
+
 class Club < ActiveRecord::Base
   has_one :membership
-  has_many :memberships, :inverse_of => false
-  has_many :members, :through => :memberships
+  has_many :memberships, inverse_of: false
+  has_many :members, through: :memberships
   has_one :sponsor
-  has_one :sponsored_member, :through => :sponsor, :source => :sponsorable, :source_type => "Member"
+  has_one :sponsored_member, through: :sponsor, source: :sponsorable, source_type: "Member"
   belongs_to :category
 
   has_many :favourites, -> { where(memberships: { favourite: true }) }, through: :memberships, source: :member
 
+  scope :general, -> { left_joins(:category).where(categories: { name: "General" }) }
+
   private
 
-  def private_method
-    "I'm sorry sir, this is a *private* club, not a *pirate* club"
-  end
+    def private_method
+      "I'm sorry sir, this is a *private* club, not a *pirate* club"
+    end
 end
 
 class SuperClub < ActiveRecord::Base
   self.table_name = "clubs"
 
-  has_many :memberships, class_name: 'SuperMembership', foreign_key: 'club_id'
+  has_many :memberships, class_name: "SuperMembership", foreign_key: "club_id"
   has_many :members, through: :memberships
 end
diff --git a/activerecord/test/models/college.rb b/activerecord/test/models/college.rb
index 501af4a8dd..52017dda42 100644
--- a/activerecord/test/models/college.rb
+++ b/activerecord/test/models/college.rb
@@ -1,5 +1,7 @@
-require_dependency 'models/arunit2_model'
-require 'active_support/core_ext/object/with_options'
+# frozen_string_literal: true
+
+require_dependency "models/arunit2_model"
+require "active_support/core_ext/object/with_options"
 
 class College < ARUnit2Model
   has_many :courses
diff --git a/activerecord/test/models/column.rb b/activerecord/test/models/column.rb
index 499358b4cf..d3cd419a00 100644
--- a/activerecord/test/models/column.rb
+++ b/activerecord/test/models/column.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Column < ActiveRecord::Base
   belongs_to :record
 end
diff --git a/activerecord/test/models/column_name.rb b/activerecord/test/models/column_name.rb
index 460eb4fe20..c6047c507b 100644
--- a/activerecord/test/models/column_name.rb
+++ b/activerecord/test/models/column_name.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class ColumnName < ActiveRecord::Base
   self.table_name = "colnametests"
 end
diff --git a/activerecord/test/models/comment.rb b/activerecord/test/models/comment.rb
index dcc5c5a310..5ab433f2d9 100644
--- a/activerecord/test/models/comment.rb
+++ b/activerecord/test/models/comment.rb
@@ -1,26 +1,47 @@
+# frozen_string_literal: true
+
+# `counter_cache` requires association class before `attr_readonly`.
+class Post < ActiveRecord::Base; end
+
 class Comment < ActiveRecord::Base
-  scope :limit_by, lambda {|l| limit(l) }
+  scope :limit_by, lambda { |l| limit(l) }
   scope :containing_the_letter_e, -> { where("comments.body LIKE '%e%'") }
   scope :not_again, -> { where("comments.body NOT LIKE '%again%'") }
-  scope :for_first_post, -> { where(:post_id => 1) }
+  scope :for_first_post, -> { where(post_id: 1) }
   scope :for_first_author, -> { joins(:post).where("posts.author_id" => 1) }
   scope :created, -> { all }
 
-  belongs_to :post, :counter_cache => true
+  belongs_to :post, counter_cache: true
   belongs_to :author,   polymorphic: true
   belongs_to :resource, polymorphic: true
-  belongs_to :developer
 
   has_many :ratings
 
-  belongs_to :first_post, :foreign_key => :post_id
+  belongs_to :first_post, foreign_key: :post_id
   belongs_to :special_post_with_default_scope, foreign_key: :post_id
 
-  has_many :children, :class_name => 'Comment', :foreign_key => :parent_id
-  belongs_to :parent, :class_name => 'Comment', :counter_cache => :children_count
+  has_many :children, class_name: "Comment", foreign_key: :parent_id
+  belongs_to :parent, class_name: "Comment", counter_cache: :children_count
+
+  class ::OopsError < RuntimeError; end
+
+  module OopsExtension
+    def destroy_all(*)
+      raise OopsError
+    end
+  end
+
+  default_scope { extending OopsExtension }
+
+  scope :oops_comments, -> { extending OopsExtension }
+
+  # Should not be called if extending modules that having the method exists on an association.
+  def self.greeting
+    raise
+  end
 
   def self.what_are_you
-    'a comment...'
+    "a comment..."
   end
 
   def self.search_by_type(q)
@@ -38,6 +59,11 @@ class Comment < ActiveRecord::Base
 end
 
 class SpecialComment < Comment
+  default_scope { where(deleted_at: nil) }
+
+  def self.what_are_you
+    "a special comment..."
+  end
 end
 
 class SubSpecialComment < SpecialComment
@@ -55,6 +81,12 @@ class CommentThatAutomaticallyAltersPostBody < Comment
 end
 
 class CommentWithDefaultScopeReferencesAssociation < Comment
-  default_scope ->{ includes(:developer).order('developers.name').references(:developer) }
+  default_scope -> { includes(:developer).order("developers.name").references(:developer) }
   belongs_to :developer
 end
+
+class CommentWithAfterCreateUpdate < Comment
+  after_create do
+    update_attributes(body: "bar")
+  end
+end
diff --git a/activerecord/test/models/company.rb b/activerecord/test/models/company.rb
index 1dcd9fc21e..fc6488f729 100644
--- a/activerecord/test/models/company.rb
+++ b/activerecord/test/models/company.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class AbstractCompany < ActiveRecord::Base
   self.abstract_class = true
 end
@@ -7,13 +9,13 @@ class Company < AbstractCompany
 
   validates_presence_of :name
 
-  has_one :dummy_account, :foreign_key => "firm_id", :class_name => "Account"
+  has_one :dummy_account, foreign_key: "firm_id", class_name: "Account"
   has_many :contracts
-  has_many :developers, :through => :contracts
+  has_many :developers, through: :contracts
 
   scope :of_first_firm, lambda {
-    joins(:account => :firm).
-    where('firms.id' => 1)
+    joins(account: :firm).
+    where("firms.id" => 1)
   }
 
   def arbitrary_method
@@ -22,12 +24,12 @@ class Company < AbstractCompany
 
   private
 
-  def private_method
-    "I am Jack's innermost fears and aspirations"
-  end
+    def private_method
+      "I am Jack's innermost fears and aspirations"
+    end
 
-  class SpecialCo < Company
-  end
+    class SpecialCo < Company
+    end
 end
 
 module Namespaced
@@ -35,7 +37,7 @@ module Namespaced
   end
 
   class Firm < ::Company
-    has_many :clients, :class_name => 'Namespaced::Client'
+    has_many :clients, class_name: "Namespaced::Client"
   end
 
   class Client < ::Company
@@ -45,45 +47,47 @@ end
 class Firm < Company
   to_param :name
 
-  has_many :clients, -> { order "id" }, :dependent => :destroy, :before_remove => :log_before_remove, :after_remove  => :log_after_remove
-  has_many :unsorted_clients, :class_name => "Client"
-  has_many :unsorted_clients_with_symbol, :class_name => :Client
-  has_many :clients_sorted_desc, -> { order "id DESC" }, :class_name => "Client"
-  has_many :clients_of_firm, -> { order "id" }, :foreign_key => "client_of", :class_name => "Client", :inverse_of => :firm
-  has_many :clients_ordered_by_name, -> { order "name" }, :class_name => "Client"
-  has_many :unvalidated_clients_of_firm, :foreign_key => "client_of", :class_name => "Client", :validate => false
-  has_many :dependent_clients_of_firm, -> { order "id" }, :foreign_key => "client_of", :class_name => "Client", :dependent => :destroy
-  has_many :exclusively_dependent_clients_of_firm, -> { order "id" }, :foreign_key => "client_of", :class_name => "Client", :dependent => :delete_all
-  has_many :limited_clients, -> { limit 1 }, :class_name => "Client"
-  has_many :clients_with_interpolated_conditions, ->(firm) { where "rating > #{firm.rating}" }, :class_name => "Client"
-  has_many :clients_like_ms, -> { where("name = 'Microsoft'").order("id") }, :class_name => "Client"
-  has_many :clients_like_ms_with_hash_conditions, -> { where(:name => 'Microsoft').order("id") }, :class_name => "Client"
-  has_many :plain_clients, :class_name => 'Client'
-  has_many :clients_using_primary_key, :class_name => 'Client',
-           :primary_key => 'name', :foreign_key => 'firm_name'
-  has_many :clients_using_primary_key_with_delete_all, :class_name => 'Client',
-           :primary_key => 'name', :foreign_key => 'firm_name', :dependent => :delete_all
-  has_many :clients_grouped_by_firm_id, -> { group("firm_id").select("firm_id") }, :class_name => "Client"
-  has_many :clients_grouped_by_name, -> { group("name").select("name") }, :class_name => "Client"
-
-  has_one :account, :foreign_key => "firm_id", :dependent => :destroy, :validate => true
-  has_one :unvalidated_account, :foreign_key => "firm_id", :class_name => 'Account', :validate => false
-  has_one :account_with_select, -> { select("id, firm_id") }, :foreign_key => "firm_id", :class_name=>'Account'
-  has_one :readonly_account, -> { readonly }, :foreign_key => "firm_id", :class_name => "Account"
+  has_many :clients, -> { order "id" }, dependent: :destroy, before_remove: :log_before_remove, after_remove: :log_after_remove
+  has_many :unsorted_clients, class_name: "Client"
+  has_many :unsorted_clients_with_symbol, class_name: :Client
+  has_many :clients_sorted_desc, -> { order "id DESC" }, class_name: "Client"
+  has_many :clients_of_firm, -> { order "id" }, foreign_key: "client_of", class_name: "Client", inverse_of: :firm
+  has_many :clients_ordered_by_name, -> { order "name" }, class_name: "Client"
+  has_many :unvalidated_clients_of_firm, foreign_key: "client_of", class_name: "Client", validate: false
+  has_many :dependent_clients_of_firm, -> { order "id" }, foreign_key: "client_of", class_name: "Client", dependent: :destroy
+  has_many :exclusively_dependent_clients_of_firm, -> { order "id" }, foreign_key: "client_of", class_name: "Client", dependent: :delete_all
+  has_many :limited_clients, -> { limit 1 }, class_name: "Client"
+  has_many :clients_with_interpolated_conditions, ->(firm) { where "rating > #{firm.rating}" }, class_name: "Client"
+  has_many :clients_like_ms, -> { where("name = 'Microsoft'").order("id") }, class_name: "Client"
+  has_many :clients_like_ms_with_hash_conditions, -> { where(name: "Microsoft").order("id") }, class_name: "Client"
+  has_many :plain_clients, class_name: "Client"
+  has_many :clients_using_primary_key, class_name: "Client",
+           primary_key: "name", foreign_key: "firm_name"
+  has_many :clients_using_primary_key_with_delete_all, class_name: "Client",
+           primary_key: "name", foreign_key: "firm_name", dependent: :delete_all
+  has_many :clients_grouped_by_firm_id, -> { group("firm_id").select("firm_id") }, class_name: "Client"
+  has_many :clients_grouped_by_name, -> { group("name").select("name") }, class_name: "Client"
+
+  has_one :account, foreign_key: "firm_id", dependent: :destroy, validate: true
+  has_one :unvalidated_account, foreign_key: "firm_id", class_name: "Account", validate: false
+  has_one :account_with_select, -> { select("id, firm_id") }, foreign_key: "firm_id", class_name: "Account"
+  has_one :readonly_account, -> { readonly }, foreign_key: "firm_id", class_name: "Account"
   # added order by id as in fixtures there are two accounts for Rails Core
   # Oracle tests were failing because of that as the second fixture was selected
-  has_one :account_using_primary_key, -> { order('id') }, :primary_key => "firm_id", :class_name => "Account"
-  has_one :account_using_foreign_and_primary_keys, :foreign_key => "firm_name", :primary_key => "name", :class_name => "Account"
-  has_one :account_with_inexistent_foreign_key, class_name: 'Account', foreign_key: "inexistent"
-  has_one :deletable_account, :foreign_key => "firm_id", :class_name => "Account", :dependent => :delete
+  has_one :account_using_primary_key, -> { order("id") }, primary_key: "firm_id", class_name: "Account"
+  has_one :account_using_foreign_and_primary_keys, foreign_key: "firm_name", primary_key: "name", class_name: "Account"
+  has_one :account_with_inexistent_foreign_key, class_name: "Account", foreign_key: "inexistent"
+  has_one :deletable_account, foreign_key: "firm_id", class_name: "Account", dependent: :delete
 
-  has_one :account_limit_500_with_hash_conditions, -> { where :credit_limit => 500 }, :foreign_key => "firm_id", :class_name => "Account"
+  has_one :account_limit_500_with_hash_conditions, -> { where credit_limit: 500 }, foreign_key: "firm_id", class_name: "Account"
 
-  has_one :unautosaved_account, :foreign_key => "firm_id", :class_name => 'Account', :autosave => false
+  has_one :unautosaved_account, foreign_key: "firm_id", class_name: "Account", autosave: false
   has_many :accounts
-  has_many :unautosaved_accounts, :foreign_key => "firm_id", :class_name => 'Account', :autosave => false
+  has_many :unautosaved_accounts, foreign_key: "firm_id", class_name: "Account", autosave: false
 
-  has_many :association_with_references, -> { references(:foo) }, :class_name => 'Client'
+  has_many :association_with_references, -> { references(:foo) }, class_name: "Client"
+
+  has_many :developers_with_select, -> { select("id, name, first_name") }, class_name: "Developer"
 
   has_one :lead_developer, class_name: "Developer"
   has_many :projects
@@ -103,32 +107,32 @@ class Firm < Company
 end
 
 class DependentFirm < Company
-  has_one :account, :foreign_key => "firm_id", :dependent => :nullify
-  has_many :companies, :foreign_key => 'client_of', :dependent => :nullify
-  has_one :company, :foreign_key => 'client_of', :dependent => :nullify
+  has_one :account, foreign_key: "firm_id", dependent: :nullify
+  has_many :companies, foreign_key: "client_of", dependent: :nullify
+  has_one :company, foreign_key: "client_of", dependent: :nullify
 end
 
 class RestrictedWithExceptionFirm < Company
-  has_one :account, -> { order("id") }, :foreign_key => "firm_id", :dependent => :restrict_with_exception
-  has_many :companies, -> { order("id") }, :foreign_key => 'client_of', :dependent => :restrict_with_exception
+  has_one :account, -> { order("id") }, foreign_key: "firm_id", dependent: :restrict_with_exception
+  has_many :companies, -> { order("id") }, foreign_key: "client_of", dependent: :restrict_with_exception
 end
 
 class RestrictedWithErrorFirm < Company
-  has_one :account, -> { order("id") }, :foreign_key => "firm_id", :dependent => :restrict_with_error
-  has_many :companies, -> { order("id") }, :foreign_key => 'client_of', :dependent => :restrict_with_error
+  has_one :account, -> { order("id") }, foreign_key: "firm_id", dependent: :restrict_with_error
+  has_many :companies, -> { order("id") }, foreign_key: "client_of", dependent: :restrict_with_error
 end
 
 class Client < Company
-  belongs_to :firm, :foreign_key => "client_of"
-  belongs_to :firm_with_basic_id, :class_name => "Firm", :foreign_key => "firm_id"
-  belongs_to :firm_with_select, -> { select("id") }, :class_name => "Firm", :foreign_key => "firm_id"
-  belongs_to :firm_with_other_name, :class_name => "Firm", :foreign_key => "client_of"
-  belongs_to :firm_with_condition, -> { where "1 = ?", 1 }, :class_name => "Firm", :foreign_key => "client_of"
-  belongs_to :firm_with_primary_key, :class_name => "Firm", :primary_key => "name", :foreign_key => "firm_name"
-  belongs_to :firm_with_primary_key_symbols, :class_name => "Firm", :primary_key => :name, :foreign_key => :firm_name
-  belongs_to :readonly_firm, -> { readonly }, :class_name => "Firm", :foreign_key => "firm_id"
-  belongs_to :bob_firm, -> { where :name => "Bob" }, :class_name => "Firm", :foreign_key => "client_of"
-  has_many :accounts, :through => :firm, :source => :accounts
+  belongs_to :firm, foreign_key: "client_of"
+  belongs_to :firm_with_basic_id, class_name: "Firm", foreign_key: "firm_id"
+  belongs_to :firm_with_select, -> { select("id") }, class_name: "Firm", foreign_key: "firm_id"
+  belongs_to :firm_with_other_name, class_name: "Firm", foreign_key: "client_of"
+  belongs_to :firm_with_condition, -> { where "1 = ?", 1 }, class_name: "Firm", foreign_key: "client_of"
+  belongs_to :firm_with_primary_key, class_name: "Firm", primary_key: "name", foreign_key: "firm_name"
+  belongs_to :firm_with_primary_key_symbols, class_name: "Firm", primary_key: :name, foreign_key: :firm_name
+  belongs_to :readonly_firm, -> { readonly }, class_name: "Firm", foreign_key: "firm_id"
+  belongs_to :bob_firm, -> { where name: "Bob" }, class_name: "Firm", foreign_key: "client_of"
+  has_many :accounts, through: :firm, source: :accounts
   belongs_to :account
 
   validate do
@@ -151,7 +155,7 @@ class Client < Company
   # is calling client.destroy, deleting from the database, or setting
   # foreign keys to NULL.
   def self.destroyed_client_ids
-    @destroyed_client_ids ||= Hash.new { |h,k| h[k] = [] }
+    @destroyed_client_ids ||= Hash.new { |h, k| h[k] = [] }
   end
 
   before_destroy do |client|
@@ -170,20 +174,13 @@ class Client < Company
 
   def overwrite_to_raise
   end
-
-  class << self
-    private
-
-    def private_method
-      "darkness"
-    end
-  end
 end
 
 class ExclusivelyDependentFirm < Company
-  has_one :account, :foreign_key => "firm_id", :dependent => :delete
-  has_many :dependent_sanitized_conditional_clients_of_firm, -> { order("id").where("name = 'BigShot Inc.'") }, :foreign_key => "client_of", :class_name => "Client", :dependent => :delete_all
-  has_many :dependent_conditional_clients_of_firm, -> { order("id").where("name = ?", 'BigShot Inc.') }, :foreign_key => "client_of", :class_name => "Client", :dependent => :delete_all
+  has_one :account, foreign_key: "firm_id", dependent: :delete
+  has_many :dependent_sanitized_conditional_clients_of_firm, -> { order("id").where("name = 'BigShot Inc.'") }, foreign_key: "client_of", class_name: "Client", dependent: :delete_all
+  has_many :dependent_hash_conditional_clients_of_firm, -> { order("id").where(name: "BigShot Inc.") }, foreign_key: "client_of", class_name: "Client", dependent: :delete_all
+  has_many :dependent_conditional_clients_of_firm, -> { order("id").where("name = ?", "BigShot Inc.") }, foreign_key: "client_of", class_name: "Client", dependent: :delete_all
 end
 
 class SpecialClient < Client
@@ -192,39 +189,4 @@ end
 class VerySpecialClient < SpecialClient
 end
 
-class Account < ActiveRecord::Base
-  belongs_to :firm, :class_name => 'Company'
-  belongs_to :unautosaved_firm, :foreign_key => "firm_id", :class_name => "Firm", :autosave => false
-
-  alias_attribute :available_credit, :credit_limit
-
-  def self.destroyed_account_ids
-    @destroyed_account_ids ||= Hash.new { |h,k| h[k] = [] }
-  end
-
-  # Test private kernel method through collection proxy using has_many.
-  def self.open
-    where('firm_name = ?', '37signals')
-  end
-
-  before_destroy do |account|
-    if account.firm
-      Account.destroyed_account_ids[account.firm.id] << account.id
-    end
-    true
-  end
-
-  validate :check_empty_credit_limit
-
-  protected
-
-  def check_empty_credit_limit
-    errors.add("credit_limit", :blank) if credit_limit.blank?
-  end
-
-  private
-
-  def private_method
-    "Sir, yes sir!"
-  end
-end
+require "models/account"
diff --git a/activerecord/test/models/company_in_module.rb b/activerecord/test/models/company_in_module.rb
index bf0a0d1c3e..52b7e06a63 100644
--- a/activerecord/test/models/company_in_module.rb
+++ b/activerecord/test/models/company_in_module.rb
@@ -1,4 +1,6 @@
-require 'active_support/core_ext/object/with_options'
+# frozen_string_literal: true
+
+require "active_support/core_ext/object/with_options"
 
 module MyApplication
   module Business
@@ -6,23 +8,23 @@ module MyApplication
     end
 
     class Firm < Company
-      has_many :clients, -> { order("id") }, :dependent => :destroy
-      has_many :clients_sorted_desc, -> { order("id DESC") }, :class_name => "Client"
-      has_many :clients_of_firm, -> { order "id" }, :foreign_key => "client_of", :class_name => "Client"
-      has_many :clients_like_ms, -> { where("name = 'Microsoft'").order("id") }, :class_name => "Client"
-      has_one :account, :class_name => 'MyApplication::Billing::Account', :dependent => :destroy
+      has_many :clients, -> { order("id") }, dependent: :destroy
+      has_many :clients_sorted_desc, -> { order("id DESC") }, class_name: "Client"
+      has_many :clients_of_firm, -> { order "id" }, foreign_key: "client_of", class_name: "Client"
+      has_many :clients_like_ms, -> { where("name = 'Microsoft'").order("id") }, class_name: "Client"
+      has_one :account, class_name: "MyApplication::Billing::Account", dependent: :destroy
     end
 
     class Client < Company
-      belongs_to :firm, :foreign_key => "client_of"
-      belongs_to :firm_with_other_name, :class_name => "Firm", :foreign_key => "client_of"
+      belongs_to :firm, foreign_key: "client_of"
+      belongs_to :firm_with_other_name, class_name: "Firm", foreign_key: "client_of"
 
       class Contact < ActiveRecord::Base; end
     end
 
     class Developer < ActiveRecord::Base
       has_and_belongs_to_many :projects
-      validates_length_of :name, :within => (3..20)
+      validates_length_of :name, within: (3..20)
     end
 
     class Project < ActiveRecord::Base
@@ -31,14 +33,14 @@ module MyApplication
 
     module Prefixed
       def self.table_name_prefix
-        'prefixed_'
+        "prefixed_"
       end
 
       class Company < ActiveRecord::Base
       end
 
       class Firm < Company
-        self.table_name = 'companies'
+        self.table_name = "companies"
       end
 
       module Nested
@@ -49,14 +51,14 @@ module MyApplication
 
     module Suffixed
       def self.table_name_suffix
-        '_suffixed'
+        "_suffixed"
       end
 
       class Company < ActiveRecord::Base
       end
 
       class Firm < Company
-        self.table_name = 'companies'
+        self.table_name = "companies"
       end
 
       module Nested
@@ -68,31 +70,31 @@ module MyApplication
 
   module Billing
     class Firm < ActiveRecord::Base
-      self.table_name = 'companies'
+      self.table_name = "companies"
     end
 
     module Nested
       class Firm < ActiveRecord::Base
-        self.table_name = 'companies'
+        self.table_name = "companies"
       end
     end
 
     class Account < ActiveRecord::Base
-      with_options(:foreign_key => :firm_id) do |i|
-        i.belongs_to :firm, :class_name => 'MyApplication::Business::Firm'
-        i.belongs_to :qualified_billing_firm, :class_name => 'MyApplication::Billing::Firm'
-        i.belongs_to :unqualified_billing_firm, :class_name => 'Firm'
-        i.belongs_to :nested_qualified_billing_firm, :class_name => 'MyApplication::Billing::Nested::Firm'
-        i.belongs_to :nested_unqualified_billing_firm, :class_name => 'Nested::Firm'
+      with_options(foreign_key: :firm_id) do |i|
+        i.belongs_to :firm, class_name: "MyApplication::Business::Firm"
+        i.belongs_to :qualified_billing_firm, class_name: "MyApplication::Billing::Firm"
+        i.belongs_to :unqualified_billing_firm, class_name: "Firm"
+        i.belongs_to :nested_qualified_billing_firm, class_name: "MyApplication::Billing::Nested::Firm"
+        i.belongs_to :nested_unqualified_billing_firm, class_name: "Nested::Firm"
       end
 
       validate :check_empty_credit_limit
 
-      protected
+      private
 
-      def check_empty_credit_limit
-        errors.add("credit_card", :blank) if credit_card.blank?
-      end
+        def check_empty_credit_limit
+          errors.add("credit_card", :blank) if credit_card.blank?
+        end
     end
   end
 end
diff --git a/activerecord/test/models/computer.rb b/activerecord/test/models/computer.rb
index cc8deb1b2b..582b4a38b5 100644
--- a/activerecord/test/models/computer.rb
+++ b/activerecord/test/models/computer.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Computer < ActiveRecord::Base
-  belongs_to :developer, :foreign_key=>'developer'
+  belongs_to :developer, foreign_key: "developer"
 end
diff --git a/activerecord/test/models/contact.rb b/activerecord/test/models/contact.rb
index 9f2f69e1ee..6e02ff199b 100644
--- a/activerecord/test/models/contact.rb
+++ b/activerecord/test/models/contact.rb
@@ -1,11 +1,13 @@
+# frozen_string_literal: true
+
 module ContactFakeColumns
   def self.extended(base)
     base.class_eval do
-      establish_connection(:adapter => 'fake')
+      establish_connection(adapter: "fake")
 
       connection.data_sources = [table_name]
       connection.primary_keys = {
-        table_name => 'id'
+        table_name => "id"
       }
 
       column :id,             :integer
@@ -19,7 +21,7 @@ module ContactFakeColumns
 
       serialize :preferences
 
-      belongs_to :alternative, :class_name => 'Contact'
+      belongs_to :alternative, class_name: "Contact"
     end
   end
 
@@ -37,5 +39,5 @@ class ContactSti < ActiveRecord::Base
   extend ContactFakeColumns
   column :type, :string
 
-  def type; 'ContactSti' end
+  def type; "ContactSti" end
 end
diff --git a/activerecord/test/models/content.rb b/activerecord/test/models/content.rb
index 140e1dfc78..14bbee53d8 100644
--- a/activerecord/test/models/content.rb
+++ b/activerecord/test/models/content.rb
@@ -1,5 +1,7 @@
+# frozen_string_literal: true
+
 class Content < ActiveRecord::Base
-  self.table_name = 'content'
+  self.table_name = "content"
   has_one :content_position, dependent: :destroy
 
   def self.destroyed_ids
@@ -12,8 +14,8 @@ class Content < ActiveRecord::Base
 end
 
 class ContentWhichRequiresTwoDestroyCalls < ActiveRecord::Base
-  self.table_name = 'content'
-  has_one :content_position, foreign_key: 'content_id', dependent: :destroy
+  self.table_name = "content"
+  has_one :content_position, foreign_key: "content_id", dependent: :destroy
 
   after_initialize do
     @destroy_count = 0
diff --git a/activerecord/test/models/contract.rb b/activerecord/test/models/contract.rb
index cdf7b267b5..f273badd85 100644
--- a/activerecord/test/models/contract.rb
+++ b/activerecord/test/models/contract.rb
@@ -1,7 +1,9 @@
+# frozen_string_literal: true
+
 class Contract < ActiveRecord::Base
   belongs_to :company
-  belongs_to :developer
-  belongs_to :firm, :foreign_key => 'company_id'
+  belongs_to :developer, primary_key: :id
+  belongs_to :firm, foreign_key: "company_id"
 
   before_save :hi
   after_save :bye
diff --git a/activerecord/test/models/country.rb b/activerecord/test/models/country.rb
index 7db9a4e731..0c84a40de2 100644
--- a/activerecord/test/models/country.rb
+++ b/activerecord/test/models/country.rb
@@ -1,7 +1,7 @@
-class Country < ActiveRecord::Base
+# frozen_string_literal: true
 
+class Country < ActiveRecord::Base
   self.primary_key = :country_id
 
   has_and_belongs_to_many :treaties
-
 end
diff --git a/activerecord/test/models/course.rb b/activerecord/test/models/course.rb
index f3d0e05ff7..4f346124ea 100644
--- a/activerecord/test/models/course.rb
+++ b/activerecord/test/models/course.rb
@@ -1,4 +1,6 @@
-require_dependency 'models/arunit2_model'
+# frozen_string_literal: true
+
+require_dependency "models/arunit2_model"
 
 class Course < ARUnit2Model
   belongs_to :college
diff --git a/activerecord/test/models/customer.rb b/activerecord/test/models/customer.rb
index 3338aaf7e1..524a9d7bd9 100644
--- a/activerecord/test/models/customer.rb
+++ b/activerecord/test/models/customer.rb
@@ -1,12 +1,15 @@
+# frozen_string_literal: true
+
 class Customer < ActiveRecord::Base
   cattr_accessor :gps_conversion_was_run
 
-  composed_of :address, :mapping => [ %w(address_street street), %w(address_city city), %w(address_country country) ], :allow_nil => true
-  composed_of :balance, :class_name => "Money", :mapping => %w(balance amount), :converter => Proc.new(&:to_money)
-  composed_of :gps_location, :allow_nil => true
-  composed_of :non_blank_gps_location, :class_name => "GpsLocation", :allow_nil => true, :mapping => %w(gps_location gps_location),
-              :converter => lambda { |gps| self.gps_conversion_was_run = true; gps.blank? ? nil : GpsLocation.new(gps)}
-  composed_of :fullname, :mapping => %w(name to_s), :constructor => Proc.new { |name| Fullname.parse(name) }, :converter => :parse
+  composed_of :address, mapping: [ %w(address_street street), %w(address_city city), %w(address_country country) ], allow_nil: true
+  composed_of :balance, class_name: "Money", mapping: %w(balance amount), converter: Proc.new(&:to_money)
+  composed_of :gps_location, allow_nil: true
+  composed_of :non_blank_gps_location, class_name: "GpsLocation", allow_nil: true, mapping: %w(gps_location gps_location),
+              converter: lambda { |gps| self.gps_conversion_was_run = true; gps.blank? ? nil : GpsLocation.new(gps) }
+  composed_of :fullname, mapping: %w(name to_s), constructor: Proc.new { |name| Fullname.parse(name) }, converter: :parse
+  composed_of :fullname_no_converter, mapping: %w(name to_s), class_name: "Fullname"
 end
 
 class Address
@@ -55,7 +58,7 @@ class GpsLocation
   end
 
   def ==(other)
-    self.latitude == other.latitude && self.longitude == other.longitude
+    latitude == other.latitude && longitude == other.longitude
   end
 end
 
diff --git a/activerecord/test/models/customer_carrier.rb b/activerecord/test/models/customer_carrier.rb
index 37186903ff..6cb9d5239d 100644
--- a/activerecord/test/models/customer_carrier.rb
+++ b/activerecord/test/models/customer_carrier.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class CustomerCarrier < ActiveRecord::Base
   cattr_accessor :current_customer
 
diff --git a/activerecord/test/models/dashboard.rb b/activerecord/test/models/dashboard.rb
index 1b3b54545f..d25ceeafb1 100644
--- a/activerecord/test/models/dashboard.rb
+++ b/activerecord/test/models/dashboard.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Dashboard < ActiveRecord::Base
   self.primary_key = :dashboard_id
 end
diff --git a/activerecord/test/models/default.rb b/activerecord/test/models/default.rb
index 887e9cc999..90f1046d87 100644
--- a/activerecord/test/models/default.rb
+++ b/activerecord/test/models/default.rb
@@ -1,2 +1,4 @@
+# frozen_string_literal: true
+
 class Default < ActiveRecord::Base
 end
diff --git a/activerecord/test/models/department.rb b/activerecord/test/models/department.rb
index 08004a0ed3..868b9bf4bf 100644
--- a/activerecord/test/models/department.rb
+++ b/activerecord/test/models/department.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Department < ActiveRecord::Base
   has_many :chefs
   belongs_to :hotel
diff --git a/activerecord/test/models/developer.rb b/activerecord/test/models/developer.rb
index 9a907273f8..8881c69368 100644
--- a/activerecord/test/models/developer.rb
+++ b/activerecord/test/models/developer.rb
@@ -1,4 +1,6 @@
-require 'ostruct'
+# frozen_string_literal: true
+
+require "ostruct"
 
 module DeveloperProjectsAssociationExtension2
   def find_least_recent
@@ -23,35 +25,35 @@ class Developer < ActiveRecord::Base
 
   has_and_belongs_to_many :projects_extended_by_name,
       -> { extending(DeveloperProjectsAssociationExtension) },
-      :class_name => "Project",
-      :join_table => "developers_projects",
-      :association_foreign_key => "project_id"
+      class_name: "Project",
+      join_table: "developers_projects",
+      association_foreign_key: "project_id"
 
   has_and_belongs_to_many :projects_extended_by_name_twice,
       -> { extending(DeveloperProjectsAssociationExtension, DeveloperProjectsAssociationExtension2) },
-      :class_name => "Project",
-      :join_table => "developers_projects",
-      :association_foreign_key => "project_id"
+      class_name: "Project",
+      join_table: "developers_projects",
+      association_foreign_key: "project_id"
 
   has_and_belongs_to_many :projects_extended_by_name_and_block,
       -> { extending(DeveloperProjectsAssociationExtension) },
-      :class_name => "Project",
-      :join_table => "developers_projects",
-      :association_foreign_key => "project_id" do
+      class_name: "Project",
+      join_table: "developers_projects",
+      association_foreign_key: "project_id" do
         def find_least_recent
           order("id ASC").first
         end
       end
 
-  has_and_belongs_to_many :special_projects, :join_table => 'developers_projects', :association_foreign_key => 'project_id'
+  has_and_belongs_to_many :special_projects, join_table: "developers_projects", association_foreign_key: "project_id"
   has_and_belongs_to_many :sym_special_projects,
-                          :join_table => :developers_projects,
-                          :association_foreign_key => 'project_id',
-                          :class_name => 'SpecialProject'
+                          join_table: :developers_projects,
+                          association_foreign_key: "project_id",
+                          class_name: "SpecialProject"
 
   has_many :audit_logs
   has_many :contracts
-  has_many :firms, :through => :contracts, :source => :firm
+  has_many :firms, through: :contracts, source: :firm
   has_many :comments, ->(developer) { where(body: "I'm #{developer.name}") }
   has_many :ratings, through: :comments
   has_one :ship, dependent: :nullify
@@ -59,20 +61,20 @@ class Developer < ActiveRecord::Base
   belongs_to :firm
   has_many :contracted_projects, class_name: "Project"
 
-  scope :jamises, -> { where(:name => 'Jamis') }
+  scope :jamises, -> { where(name: "Jamis") }
 
-  validates_inclusion_of :salary, :in => 50000..200000
-  validates_length_of    :name, :within => 3..20
+  validates_inclusion_of :salary, in: 50000..200000
+  validates_length_of    :name, within: 3..20
 
   before_create do |developer|
-    developer.audit_logs.build :message => "Computer created"
+    developer.audit_logs.build message: "Computer created"
   end
 
   attr_accessor :last_name
-  define_attribute_method 'last_name'
+  define_attribute_method "last_name"
 
   def log=(message)
-    audit_logs.build :message => message
+    audit_logs.build message: message
   end
 
   after_find :track_instance_count
@@ -83,17 +85,27 @@ class Developer < ActiveRecord::Base
     self.class.instance_count += 1
   end
   private :track_instance_count
+end
 
+class SubDeveloper < Developer
+end
+
+class SymbolIgnoredDeveloper < ActiveRecord::Base
+  self.table_name = "developers"
+  self.ignored_columns = [:first_name, :last_name]
+
+  attr_accessor :last_name
+  define_attribute_method "last_name"
 end
 
 class AuditLog < ActiveRecord::Base
-  belongs_to :developer, :validate => true
-  belongs_to :unvalidated_developer, :class_name => 'Developer'
+  belongs_to :developer, validate: true
+  belongs_to :unvalidated_developer, class_name: "Developer"
 end
 
 class DeveloperWithBeforeDestroyRaise < ActiveRecord::Base
-  self.table_name = 'developers'
-  has_and_belongs_to_many :projects, :join_table => 'developers_projects', :foreign_key => 'developer_id'
+  self.table_name = "developers"
+  has_and_belongs_to_many :projects, join_table: "developers_projects", foreign_key: "developer_id"
   before_destroy :raise_if_projects_empty!
 
   def raise_if_projects_empty!
@@ -102,63 +114,63 @@ class DeveloperWithBeforeDestroyRaise < ActiveRecord::Base
 end
 
 class DeveloperWithSelect < ActiveRecord::Base
-  self.table_name = 'developers'
-  default_scope { select('name') }
+  self.table_name = "developers"
+  default_scope { select("name") }
 end
 
 class DeveloperWithIncludes < ActiveRecord::Base
-  self.table_name = 'developers'
-  has_many :audit_logs, :foreign_key => :developer_id
+  self.table_name = "developers"
+  has_many :audit_logs, foreign_key: :developer_id
   default_scope { includes(:audit_logs) }
 end
 
 class DeveloperFilteredOnJoins < ActiveRecord::Base
-  self.table_name = 'developers'
-  has_and_belongs_to_many :projects, -> { order('projects.id') }, :foreign_key => 'developer_id', :join_table => 'developers_projects'
+  self.table_name = "developers"
+  has_and_belongs_to_many :projects, -> { order("projects.id") }, foreign_key: "developer_id", join_table: "developers_projects"
 
   def self.default_scope
-    joins(:projects).where(:projects => { :name => 'Active Controller' })
+    joins(:projects).where(projects: { name: "Active Controller" })
   end
 end
 
 class DeveloperOrderedBySalary < ActiveRecord::Base
-  self.table_name = 'developers'
-  default_scope { order('salary DESC') }
+  self.table_name = "developers"
+  default_scope { order("salary DESC") }
 
-  scope :by_name, -> { order('name DESC') }
+  scope :by_name, -> { order("name DESC") }
 end
 
 class DeveloperCalledDavid < ActiveRecord::Base
-  self.table_name = 'developers'
+  self.table_name = "developers"
   default_scope { where("name = 'David'") }
 end
 
 class LazyLambdaDeveloperCalledDavid < ActiveRecord::Base
-  self.table_name = 'developers'
-  default_scope lambda { where(:name => 'David') }
+  self.table_name = "developers"
+  default_scope lambda { where(name: "David") }
 end
 
 class LazyBlockDeveloperCalledDavid < ActiveRecord::Base
-  self.table_name = 'developers'
-  default_scope { where(:name => 'David') }
+  self.table_name = "developers"
+  default_scope { where(name: "David") }
 end
 
 class CallableDeveloperCalledDavid < ActiveRecord::Base
-  self.table_name = 'developers'
-  default_scope OpenStruct.new(:call => where(:name => 'David'))
+  self.table_name = "developers"
+  default_scope OpenStruct.new(call: where(name: "David"))
 end
 
 class ClassMethodDeveloperCalledDavid < ActiveRecord::Base
-  self.table_name = 'developers'
+  self.table_name = "developers"
 
   def self.default_scope
-    where(:name => 'David')
+    where(name: "David")
   end
 end
 
 class ClassMethodReferencingScopeDeveloperCalledDavid < ActiveRecord::Base
-  self.table_name = 'developers'
-  scope :david, -> { where(:name => 'David') }
+  self.table_name = "developers"
+  scope :david, -> { where(name: "David") }
 
   def self.default_scope
     david
@@ -166,61 +178,61 @@ class ClassMethodReferencingScopeDeveloperCalledDavid < ActiveRecord::Base
 end
 
 class LazyBlockReferencingScopeDeveloperCalledDavid < ActiveRecord::Base
-  self.table_name = 'developers'
-  scope :david, -> { where(:name => 'David') }
+  self.table_name = "developers"
+  scope :david, -> { where(name: "David") }
   default_scope { david }
 end
 
 class DeveloperCalledJamis < ActiveRecord::Base
-  self.table_name = 'developers'
+  self.table_name = "developers"
 
-  default_scope { where(:name => 'Jamis') }
-  scope :poor, -> { where('salary < 150000') }
+  default_scope { where(name: "Jamis") }
+  scope :poor, -> { where("salary < 150000") }
   scope :david, -> { where name: "David" }
   scope :david2, -> { unscoped.where name: "David" }
 end
 
 class PoorDeveloperCalledJamis < ActiveRecord::Base
-  self.table_name = 'developers'
+  self.table_name = "developers"
 
-  default_scope -> { where(:name => 'Jamis', :salary => 50000) }
+  default_scope -> { where(name: "Jamis", salary: 50000) }
 end
 
 class InheritedPoorDeveloperCalledJamis < DeveloperCalledJamis
-  self.table_name = 'developers'
+  self.table_name = "developers"
 
-  default_scope -> { where(:salary => 50000) }
+  default_scope -> { where(salary: 50000) }
 end
 
 class MultiplePoorDeveloperCalledJamis < ActiveRecord::Base
-  self.table_name = 'developers'
+  self.table_name = "developers"
 
-  default_scope -> { where(:name => 'Jamis') }
-  default_scope -> { where(:salary => 50000) }
+  default_scope -> { where(name: "Jamis") }
+  default_scope -> { where(salary: 50000) }
 end
 
 module SalaryDefaultScope
   extend ActiveSupport::Concern
 
-  included { default_scope { where(:salary => 50000) } }
+  included { default_scope { where(salary: 50000) } }
 end
 
 class ModuleIncludedPoorDeveloperCalledJamis < DeveloperCalledJamis
-  self.table_name = 'developers'
+  self.table_name = "developers"
 
   include SalaryDefaultScope
 end
 
 class EagerDeveloperWithDefaultScope < ActiveRecord::Base
-  self.table_name = 'developers'
-  has_and_belongs_to_many :projects, -> { order('projects.id') }, :foreign_key => 'developer_id', :join_table => 'developers_projects'
+  self.table_name = "developers"
+  has_and_belongs_to_many :projects, -> { order("projects.id") }, foreign_key: "developer_id", join_table: "developers_projects"
 
   default_scope { includes(:projects) }
 end
 
 class EagerDeveloperWithClassMethodDefaultScope < ActiveRecord::Base
-  self.table_name = 'developers'
-  has_and_belongs_to_many :projects, -> { order('projects.id') }, :foreign_key => 'developer_id', :join_table => 'developers_projects'
+  self.table_name = "developers"
+  has_and_belongs_to_many :projects, -> { order("projects.id") }, foreign_key: "developer_id", join_table: "developers_projects"
 
   def self.default_scope
     includes(:projects)
@@ -228,31 +240,31 @@ class EagerDeveloperWithClassMethodDefaultScope < ActiveRecord::Base
 end
 
 class EagerDeveloperWithLambdaDefaultScope < ActiveRecord::Base
-  self.table_name = 'developers'
-  has_and_belongs_to_many :projects, -> { order('projects.id') }, :foreign_key => 'developer_id', :join_table => 'developers_projects'
+  self.table_name = "developers"
+  has_and_belongs_to_many :projects, -> { order("projects.id") }, foreign_key: "developer_id", join_table: "developers_projects"
 
   default_scope lambda { includes(:projects) }
 end
 
 class EagerDeveloperWithBlockDefaultScope < ActiveRecord::Base
-  self.table_name = 'developers'
-  has_and_belongs_to_many :projects, -> { order('projects.id') }, :foreign_key => 'developer_id', :join_table => 'developers_projects'
+  self.table_name = "developers"
+  has_and_belongs_to_many :projects, -> { order("projects.id") }, foreign_key: "developer_id", join_table: "developers_projects"
 
   default_scope { includes(:projects) }
 end
 
 class EagerDeveloperWithCallableDefaultScope < ActiveRecord::Base
-  self.table_name = 'developers'
-  has_and_belongs_to_many :projects, -> { order('projects.id') }, :foreign_key => 'developer_id', :join_table => 'developers_projects'
+  self.table_name = "developers"
+  has_and_belongs_to_many :projects, -> { order("projects.id") }, foreign_key: "developer_id", join_table: "developers_projects"
 
-  default_scope OpenStruct.new(:call => includes(:projects))
+  default_scope OpenStruct.new(call: includes(:projects))
 end
 
 class ThreadsafeDeveloper < ActiveRecord::Base
-  self.table_name = 'developers'
+  self.table_name = "developers"
 
   def self.default_scope
-    sleep 0.05 if Thread.current[:long_default_scope]
+    Thread.current[:default_scope_delay].call
     limit(1)
   end
 end
@@ -261,3 +273,9 @@ class CachedDeveloper < ActiveRecord::Base
   self.table_name = "developers"
   self.cache_timestamp_format = :number
 end
+
+class DeveloperWithIncorrectlyOrderedHasManyThrough < ActiveRecord::Base
+  self.table_name = "developers"
+  has_many :companies, through: :contracts
+  has_many :contracts, foreign_key: :developer_id
+end
diff --git a/activerecord/test/models/dog.rb b/activerecord/test/models/dog.rb
index b02b8447b8..75d284ac25 100644
--- a/activerecord/test/models/dog.rb
+++ b/activerecord/test/models/dog.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Dog < ActiveRecord::Base
   belongs_to :breeder, class_name: "DogLover", counter_cache: :bred_dogs_count
   belongs_to :trainer, class_name: "DogLover", counter_cache: :trained_dogs_count
diff --git a/activerecord/test/models/dog_lover.rb b/activerecord/test/models/dog_lover.rb
index 2c5be94aea..aabe914f77 100644
--- a/activerecord/test/models/dog_lover.rb
+++ b/activerecord/test/models/dog_lover.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class DogLover < ActiveRecord::Base
   has_many :trained_dogs, class_name: "Dog", foreign_key: :trainer_id, dependent: :destroy
   has_many :bred_dogs, class_name: "Dog", foreign_key: :breeder_id
diff --git a/activerecord/test/models/doubloon.rb b/activerecord/test/models/doubloon.rb
index 2b11d128e2..febadc3a5a 100644
--- a/activerecord/test/models/doubloon.rb
+++ b/activerecord/test/models/doubloon.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class AbstractDoubloon < ActiveRecord::Base
   # This has functionality that might be shared by multiple classes.
 
@@ -8,5 +10,5 @@ end
 class Doubloon < AbstractDoubloon
   # This uses an abstract class that defines attributes and associations.
 
-  self.table_name = 'doubloons'
+  self.table_name = "doubloons"
 end
diff --git a/activerecord/test/models/drink_designer.rb b/activerecord/test/models/drink_designer.rb
index 2db968ef11..eb6701b84e 100644
--- a/activerecord/test/models/drink_designer.rb
+++ b/activerecord/test/models/drink_designer.rb
@@ -1,3 +1,8 @@
+# frozen_string_literal: true
+
 class DrinkDesigner < ActiveRecord::Base
   has_one :chef, as: :employable
 end
+
+class MocktailDesigner < DrinkDesigner
+end
diff --git a/activerecord/test/models/edge.rb b/activerecord/test/models/edge.rb
index 55e0c31fcb..a04ab103de 100644
--- a/activerecord/test/models/edge.rb
+++ b/activerecord/test/models/edge.rb
@@ -1,5 +1,7 @@
+# frozen_string_literal: true
+
 # This class models an edge in a directed graph.
 class Edge < ActiveRecord::Base
-  belongs_to :source, :class_name => 'Vertex', :foreign_key => 'source_id'
-  belongs_to :sink,   :class_name => 'Vertex', :foreign_key => 'sink_id'
+  belongs_to :source, class_name: "Vertex", foreign_key: "source_id"
+  belongs_to :sink,   class_name: "Vertex", foreign_key: "sink_id"
 end
diff --git a/activerecord/test/models/electron.rb b/activerecord/test/models/electron.rb
index 6fc270673f..902006b314 100644
--- a/activerecord/test/models/electron.rb
+++ b/activerecord/test/models/electron.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Electron < ActiveRecord::Base
   belongs_to :molecule
 
diff --git a/activerecord/test/models/engine.rb b/activerecord/test/models/engine.rb
index 851ff8c22b..396a52b3b9 100644
--- a/activerecord/test/models/engine.rb
+++ b/activerecord/test/models/engine.rb
@@ -1,4 +1,5 @@
+# frozen_string_literal: true
+
 class Engine < ActiveRecord::Base
-  belongs_to :my_car, :class_name => 'Car', :foreign_key => 'car_id',  :counter_cache => :engines_count
+  belongs_to :my_car, class_name: "Car", foreign_key: "car_id",  counter_cache: :engines_count
 end
-
diff --git a/activerecord/test/models/entrant.rb b/activerecord/test/models/entrant.rb
index 4682ce48c8..2c086e451f 100644
--- a/activerecord/test/models/entrant.rb
+++ b/activerecord/test/models/entrant.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Entrant < ActiveRecord::Base
   belongs_to :course
 end
diff --git a/activerecord/test/models/essay.rb b/activerecord/test/models/essay.rb
index ec4b982b5b..e59db4d877 100644
--- a/activerecord/test/models/essay.rb
+++ b/activerecord/test/models/essay.rb
@@ -1,5 +1,8 @@
+# frozen_string_literal: true
+
 class Essay < ActiveRecord::Base
-  belongs_to :writer, :primary_key => :name, :polymorphic => true
-  belongs_to :category, :primary_key => :name
-  has_one :owner, :primary_key => :name
+  belongs_to :author
+  belongs_to :writer, primary_key: :name, polymorphic: true
+  belongs_to :category, primary_key: :name
+  has_one :owner, primary_key: :name
 end
diff --git a/activerecord/test/models/event.rb b/activerecord/test/models/event.rb
index 365ab32b0b..a7cdc39e5c 100644
--- a/activerecord/test/models/event.rb
+++ b/activerecord/test/models/event.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Event < ActiveRecord::Base
   validates_uniqueness_of :title
 end
diff --git a/activerecord/test/models/eye.rb b/activerecord/test/models/eye.rb
index dc8ae2b3f6..f3608b62ef 100644
--- a/activerecord/test/models/eye.rb
+++ b/activerecord/test/models/eye.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Eye < ActiveRecord::Base
   attr_reader :after_create_callbacks_stack
   attr_reader :after_update_callbacks_stack
@@ -15,19 +17,19 @@ class Eye < ActiveRecord::Base
   after_create :trace_after_create2
   after_update :trace_after_update2
   after_save   :trace_after_save2
-  
+
   def trace_after_create
     (@after_create_callbacks_stack ||= []) << !iris.persisted?
   end
   alias trace_after_create2 trace_after_create
 
   def trace_after_update
-    (@after_update_callbacks_stack ||= []) << iris.changed?
+    (@after_update_callbacks_stack ||= []) << iris.has_changes_to_save?
   end
   alias trace_after_update2 trace_after_update
 
   def trace_after_save
-    (@after_save_callbacks_stack ||= []) << iris.changed?
+    (@after_save_callbacks_stack ||= []) << iris.has_changes_to_save?
   end
   alias trace_after_save2 trace_after_save
 end
diff --git a/activerecord/test/models/face.rb b/activerecord/test/models/face.rb
index af76fea52c..948435136d 100644
--- a/activerecord/test/models/face.rb
+++ b/activerecord/test/models/face.rb
@@ -1,9 +1,15 @@
+# frozen_string_literal: true
+
 class Face < ActiveRecord::Base
-  belongs_to :man, :inverse_of => :face
-  belongs_to :polymorphic_man, :polymorphic => true, :inverse_of => :polymorphic_face
+  belongs_to :man, inverse_of: :face
+  belongs_to :polymorphic_man, polymorphic: true, inverse_of: :polymorphic_face
   # Oracle identifier length is limited to 30 bytes or less, `polymorphic` renamed `poly`
-  belongs_to :poly_man_without_inverse, :polymorphic => true
+  belongs_to :poly_man_without_inverse, polymorphic: true
   # These is a "broken" inverse_of for the purposes of testing
-  belongs_to :horrible_man, :class_name => 'Man', :inverse_of => :horrible_face
-  belongs_to :horrible_polymorphic_man, :polymorphic => true, :inverse_of => :horrible_polymorphic_face
+  belongs_to :horrible_man, class_name: "Man", inverse_of: :horrible_face
+  belongs_to :horrible_polymorphic_man, polymorphic: true, inverse_of: :horrible_polymorphic_face
+
+  validate do
+    man
+  end
 end
diff --git a/activerecord/test/models/family.rb b/activerecord/test/models/family.rb
new file mode 100644
index 0000000000..0713dba1a6
--- /dev/null
+++ b/activerecord/test/models/family.rb
@@ -0,0 +1,6 @@
+# frozen_string_literal: true
+
+class Family < ActiveRecord::Base
+  has_many :family_trees, -> { where(token: nil) }
+  has_many :members, through: :family_trees
+end
diff --git a/activerecord/test/models/family_tree.rb b/activerecord/test/models/family_tree.rb
new file mode 100644
index 0000000000..a8ea907c05
--- /dev/null
+++ b/activerecord/test/models/family_tree.rb
@@ -0,0 +1,6 @@
+# frozen_string_literal: true
+
+class FamilyTree < ActiveRecord::Base
+  belongs_to :member, class_name: "User", foreign_key: "member_id"
+  belongs_to :family
+end
diff --git a/activerecord/test/models/friendship.rb b/activerecord/test/models/friendship.rb
index 4b411ca8e0..9f1712a8ec 100644
--- a/activerecord/test/models/friendship.rb
+++ b/activerecord/test/models/friendship.rb
@@ -1,6 +1,8 @@
+# frozen_string_literal: true
+
 class Friendship < ActiveRecord::Base
-  belongs_to :friend, class_name: 'Person'
+  belongs_to :friend, class_name: "Person"
   # friend_too exists to test a bug, and probably shouldn't be used elsewhere
-  belongs_to :friend_too, foreign_key: 'friend_id', class_name: 'Person', counter_cache: :friends_too_count
-  belongs_to :follower, class_name: 'Person'
+  belongs_to :friend_too, foreign_key: "friend_id", class_name: "Person", counter_cache: :friends_too_count
+  belongs_to :follower, class_name: "Person"
 end
diff --git a/activerecord/test/models/guid.rb b/activerecord/test/models/guid.rb
index 05653ba498..ec71c37690 100644
--- a/activerecord/test/models/guid.rb
+++ b/activerecord/test/models/guid.rb
@@ -1,2 +1,4 @@
+# frozen_string_literal: true
+
 class Guid < ActiveRecord::Base
 end
diff --git a/activerecord/test/models/guitar.rb b/activerecord/test/models/guitar.rb
index cd068ff53d..649b998665 100644
--- a/activerecord/test/models/guitar.rb
+++ b/activerecord/test/models/guitar.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Guitar < ActiveRecord::Base
   has_many :tuning_pegs, index_errors: true
   accepts_nested_attributes_for :tuning_pegs
diff --git a/activerecord/test/models/hotel.rb b/activerecord/test/models/hotel.rb
index 9c90ffcff4..1a433c3cab 100644
--- a/activerecord/test/models/hotel.rb
+++ b/activerecord/test/models/hotel.rb
@@ -1,11 +1,13 @@
+# frozen_string_literal: true
+
 class Hotel < ActiveRecord::Base
   has_many :departments
   has_many :chefs, through: :departments
-  has_many :cake_designers, source_type: 'CakeDesigner', source: :employable, through: :chefs
-  has_many :drink_designers, source_type: 'DrinkDesigner', source: :employable, through: :chefs
+  has_many :cake_designers, source_type: "CakeDesigner", source: :employable, through: :chefs
+  has_many :drink_designers, source_type: "DrinkDesigner", source: :employable, through: :chefs
 
   has_many :chef_lists, as: :employable_list
-  has_many :mocktail_designers, through: :chef_lists, source: :employable, :source_type => "MocktailDesigner"
+  has_many :mocktail_designers, through: :chef_lists, source: :employable, source_type: "MocktailDesigner"
 
   has_many :recipes, through: :chefs
 end
diff --git a/activerecord/test/models/image.rb b/activerecord/test/models/image.rb
index 7ae8e4a7f6..b4808293cc 100644
--- a/activerecord/test/models/image.rb
+++ b/activerecord/test/models/image.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Image < ActiveRecord::Base
   belongs_to :imageable, foreign_key: :imageable_identifier, foreign_type: :imageable_class
 end
diff --git a/activerecord/test/models/interest.rb b/activerecord/test/models/interest.rb
index d5d9226204..899b8f9b9d 100644
--- a/activerecord/test/models/interest.rb
+++ b/activerecord/test/models/interest.rb
@@ -1,5 +1,7 @@
+# frozen_string_literal: true
+
 class Interest < ActiveRecord::Base
-  belongs_to :man, :inverse_of => :interests
-  belongs_to :polymorphic_man, :polymorphic => true, :inverse_of => :polymorphic_interests
-  belongs_to :zine, :inverse_of => :interests
+  belongs_to :man, inverse_of: :interests
+  belongs_to :polymorphic_man, polymorphic: true, inverse_of: :polymorphic_interests
+  belongs_to :zine, inverse_of: :interests
 end
diff --git a/activerecord/test/models/invoice.rb b/activerecord/test/models/invoice.rb
index fc6ef0230e..1851792ed5 100644
--- a/activerecord/test/models/invoice.rb
+++ b/activerecord/test/models/invoice.rb
@@ -1,4 +1,6 @@
+# frozen_string_literal: true
+
 class Invoice < ActiveRecord::Base
-  has_many :line_items, :autosave => true
-  before_save {|record| record.balance = record.line_items.map(&:amount).sum }
+  has_many :line_items, autosave: true
+  before_save { |record| record.balance = record.line_items.map(&:amount).sum }
 end
diff --git a/activerecord/test/models/item.rb b/activerecord/test/models/item.rb
index c2571dd7fb..8d079d56e6 100644
--- a/activerecord/test/models/item.rb
+++ b/activerecord/test/models/item.rb
@@ -1,6 +1,8 @@
+# frozen_string_literal: true
+
 class AbstractItem < ActiveRecord::Base
   self.abstract_class = true
-  has_one :tagging, :as => :taggable
+  has_one :tagging, as: :taggable
 end
 
 class Item < AbstractItem
diff --git a/activerecord/test/models/job.rb b/activerecord/test/models/job.rb
index f7b0e787b1..52817a8435 100644
--- a/activerecord/test/models/job.rb
+++ b/activerecord/test/models/job.rb
@@ -1,7 +1,9 @@
+# frozen_string_literal: true
+
 class Job < ActiveRecord::Base
   has_many :references
-  has_many :people, :through => :references
-  belongs_to :ideal_reference, :class_name => 'Reference'
+  has_many :people, through: :references
+  belongs_to :ideal_reference, class_name: "Reference"
 
-  has_many :agents, :through => :people
+  has_many :agents, through: :people
 end
diff --git a/activerecord/test/models/joke.rb b/activerecord/test/models/joke.rb
index edda4655dc..436ffb6471 100644
--- a/activerecord/test/models/joke.rb
+++ b/activerecord/test/models/joke.rb
@@ -1,7 +1,9 @@
+# frozen_string_literal: true
+
 class Joke < ActiveRecord::Base
-  self.table_name = 'funny_jokes'
+  self.table_name = "funny_jokes"
 end
 
 class GoodJoke < ActiveRecord::Base
-  self.table_name = 'funny_jokes'
+  self.table_name = "funny_jokes"
 end
diff --git a/activerecord/test/models/keyboard.rb b/activerecord/test/models/keyboard.rb
index 39347e274e..d200e0fb56 100644
--- a/activerecord/test/models/keyboard.rb
+++ b/activerecord/test/models/keyboard.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Keyboard < ActiveRecord::Base
-  self.primary_key = 'key_number'
+  self.primary_key = "key_number"
 end
diff --git a/activerecord/test/models/legacy_thing.rb b/activerecord/test/models/legacy_thing.rb
index eead181a0e..e0210c8922 100644
--- a/activerecord/test/models/legacy_thing.rb
+++ b/activerecord/test/models/legacy_thing.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class LegacyThing < ActiveRecord::Base
   self.locking_column = :version
 end
diff --git a/activerecord/test/models/lesson.rb b/activerecord/test/models/lesson.rb
index 4c88153068..e546339689 100644
--- a/activerecord/test/models/lesson.rb
+++ b/activerecord/test/models/lesson.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class LessonError < Exception
 end
 
diff --git a/activerecord/test/models/line_item.rb b/activerecord/test/models/line_item.rb
index 0dd921a300..3a51cf03b2 100644
--- a/activerecord/test/models/line_item.rb
+++ b/activerecord/test/models/line_item.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class LineItem < ActiveRecord::Base
-  belongs_to :invoice, :touch => true
+  belongs_to :invoice, touch: true
 end
diff --git a/activerecord/test/models/liquid.rb b/activerecord/test/models/liquid.rb
index 69d4d7df1a..b2fd305d66 100644
--- a/activerecord/test/models/liquid.rb
+++ b/activerecord/test/models/liquid.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Liquid < ActiveRecord::Base
   self.table_name = :liquid
   has_many :molecules, -> { distinct }
diff --git a/activerecord/test/models/man.rb b/activerecord/test/models/man.rb
index 4fbb6b226b..3acd89a48e 100644
--- a/activerecord/test/models/man.rb
+++ b/activerecord/test/models/man.rb
@@ -1,11 +1,13 @@
+# frozen_string_literal: true
+
 class Man < ActiveRecord::Base
-  has_one :face, :inverse_of => :man
-  has_one :polymorphic_face, :class_name => 'Face', :as => :polymorphic_man, :inverse_of => :polymorphic_man
-  has_one :polymorphic_face_without_inverse, :class_name => 'Face', :as => :poly_man_without_inverse
-  has_many :interests, :inverse_of => :man
-  has_many :polymorphic_interests, :class_name => 'Interest', :as => :polymorphic_man, :inverse_of => :polymorphic_man
+  has_one :face, inverse_of: :man
+  has_one :polymorphic_face, class_name: "Face", as: :polymorphic_man, inverse_of: :polymorphic_man
+  has_one :polymorphic_face_without_inverse, class_name: "Face", as: :poly_man_without_inverse
+  has_many :interests, inverse_of: :man
+  has_many :polymorphic_interests, class_name: "Interest", as: :polymorphic_man, inverse_of: :polymorphic_man
   # These are "broken" inverse_of associations for the purposes of testing
-  has_one :dirty_face, :class_name => 'Face', :inverse_of => :dirty_man
-  has_many :secret_interests, :class_name => 'Interest', :inverse_of => :secret_man
+  has_one :dirty_face, class_name: "Face", inverse_of: :dirty_man
+  has_many :secret_interests, class_name: "Interest", inverse_of: :secret_man
   has_one :mixed_case_monkey
 end
diff --git a/activerecord/test/models/matey.rb b/activerecord/test/models/matey.rb
index 47b0baa974..a77ac21e96 100644
--- a/activerecord/test/models/matey.rb
+++ b/activerecord/test/models/matey.rb
@@ -1,4 +1,6 @@
+# frozen_string_literal: true
+
 class Matey < ActiveRecord::Base
   belongs_to :pirate
-  belongs_to :target, :class_name => 'Pirate'
+  belongs_to :target, class_name: "Pirate"
 end
diff --git a/activerecord/test/models/member.rb b/activerecord/test/models/member.rb
index 7693c6e515..4315ba1941 100644
--- a/activerecord/test/models/member.rb
+++ b/activerecord/test/models/member.rb
@@ -1,35 +1,38 @@
+# frozen_string_literal: true
+
 class Member < ActiveRecord::Base
   has_one :current_membership
   has_one :selected_membership
   has_one :membership
-  has_one :club, :through => :current_membership
-  has_one :selected_club, :through => :selected_membership, :source => :club
-  has_one :favourite_club, -> { where "memberships.favourite = ?", true }, :through => :membership, :source => :club
-  has_one :hairy_club, -> { where :clubs => {:name => "Moustache and Eyebrow Fancier Club"} }, :through => :membership, :source => :club
-  has_one :sponsor, :as => :sponsorable
-  has_one :sponsor_club, :through => :sponsor
-  has_one :member_detail, :inverse_of => false
-  has_one :organization, :through => :member_detail
+  has_one :club, through: :current_membership
+  has_one :selected_club, through: :selected_membership, source: :club
+  has_one :favourite_club, -> { where "memberships.favourite = ?", true }, through: :membership, source: :club
+  has_one :hairy_club, -> { where clubs: { name: "Moustache and Eyebrow Fancier Club" } }, through: :membership, source: :club
+  has_one :sponsor, as: :sponsorable
+  has_one :sponsor_club, through: :sponsor
+  has_one :member_detail, inverse_of: false
+  has_one :organization, through: :member_detail
   belongs_to :member_type
 
-  has_many :nested_member_types, :through => :member_detail, :source => :member_type
-  has_one :nested_member_type, :through => :member_detail, :source => :member_type
+  has_many :nested_member_types, through: :member_detail, source: :member_type
+  has_one :nested_member_type, through: :member_detail, source: :member_type
 
-  has_many :nested_sponsors, :through => :sponsor_club, :source => :sponsor
-  has_one :nested_sponsor, :through => :sponsor_club, :source => :sponsor
+  has_many :nested_sponsors, through: :sponsor_club, source: :sponsor
+  has_one :nested_sponsor, through: :sponsor_club, source: :sponsor
 
-  has_many :organization_member_details, :through => :member_detail
-  has_many :organization_member_details_2, :through => :organization, :source => :member_details
+  has_many :organization_member_details, through: :member_detail
+  has_many :organization_member_details_2, through: :organization, source: :member_details
 
-  has_one :club_category, :through => :club, :source => :category
+  has_one :club_category, through: :club, source: :category
+  has_one :general_club, -> { general }, through: :current_membership, source: :club
 
-  has_many :current_memberships, -> { where :favourite => true }
-  has_many :clubs, :through => :current_memberships
+  has_many :current_memberships, -> { where favourite: true }
+  has_many :clubs, through: :current_memberships
 
   has_many :tenant_memberships
-  has_many :tenant_clubs, through: :tenant_memberships, class_name: 'Club', source: :club
+  has_many :tenant_clubs, through: :tenant_memberships, class_name: "Club", source: :club
 
-  has_one :club_through_many, :through => :current_memberships, :source => :club
+  has_one :club_through_many, through: :current_memberships, source: :club
 
   belongs_to :admittable, polymorphic: true
   has_one :premium_club, through: :admittable
@@ -37,5 +40,5 @@ end
 
 class SelfMember < ActiveRecord::Base
   self.table_name = "members"
-  has_and_belongs_to_many :friends, :class_name => "SelfMember", :join_table => "member_friends"
+  has_and_belongs_to_many :friends, class_name: "SelfMember", join_table: "member_friends"
 end
diff --git a/activerecord/test/models/member_detail.rb b/activerecord/test/models/member_detail.rb
index 157130986c..87f7aab9a2 100644
--- a/activerecord/test/models/member_detail.rb
+++ b/activerecord/test/models/member_detail.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class MemberDetail < ActiveRecord::Base
   belongs_to :member, inverse_of: false
   belongs_to :organization
diff --git a/activerecord/test/models/member_type.rb b/activerecord/test/models/member_type.rb
index a13561c72a..b49b168d03 100644
--- a/activerecord/test/models/member_type.rb
+++ b/activerecord/test/models/member_type.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class MemberType < ActiveRecord::Base
   has_many :members
 end
diff --git a/activerecord/test/models/membership.rb b/activerecord/test/models/membership.rb
index e181ba1f11..09ee7544b3 100644
--- a/activerecord/test/models/membership.rb
+++ b/activerecord/test/models/membership.rb
@@ -1,4 +1,7 @@
+# frozen_string_literal: true
+
 class Membership < ActiveRecord::Base
+  enum type: %i(Membership CurrentMembership SuperMembership SelectedMembership TenantMembership)
   belongs_to :member
   belongs_to :club
 end
@@ -9,7 +12,7 @@ class CurrentMembership < Membership
 end
 
 class SuperMembership < Membership
-  belongs_to :member, -> { order('members.id DESC') }
+  belongs_to :member, -> { order("members.id DESC") }
   belongs_to :club
 end
 
diff --git a/activerecord/test/models/mentor.rb b/activerecord/test/models/mentor.rb
index 11f1e4bff8..2fbb62c435 100644
--- a/activerecord/test/models/mentor.rb
+++ b/activerecord/test/models/mentor.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Mentor < ActiveRecord::Base
   has_many :developers
-end
\ No newline at end of file
+end
diff --git a/activerecord/test/models/minimalistic.rb b/activerecord/test/models/minimalistic.rb
index 2e3f8e081a..c67b086853 100644
--- a/activerecord/test/models/minimalistic.rb
+++ b/activerecord/test/models/minimalistic.rb
@@ -1,2 +1,4 @@
+# frozen_string_literal: true
+
 class Minimalistic < ActiveRecord::Base
 end
diff --git a/activerecord/test/models/minivan.rb b/activerecord/test/models/minivan.rb
index 4fe79720ad..d9d331798a 100644
--- a/activerecord/test/models/minivan.rb
+++ b/activerecord/test/models/minivan.rb
@@ -1,9 +1,10 @@
+# frozen_string_literal: true
+
 class Minivan < ActiveRecord::Base
   self.primary_key = :minivan_id
 
   belongs_to :speedometer
-  has_one :dashboard, :through => :speedometer
+  has_one :dashboard, through: :speedometer
 
   attr_readonly :color
-
 end
diff --git a/activerecord/test/models/mixed_case_monkey.rb b/activerecord/test/models/mixed_case_monkey.rb
index 1c35006665..8e92f68817 100644
--- a/activerecord/test/models/mixed_case_monkey.rb
+++ b/activerecord/test/models/mixed_case_monkey.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class MixedCaseMonkey < ActiveRecord::Base
   belongs_to :man
 end
diff --git a/activerecord/test/models/mocktail_designer.rb b/activerecord/test/models/mocktail_designer.rb
deleted file mode 100644
index 77b44651a3..0000000000
--- a/activerecord/test/models/mocktail_designer.rb
+++ /dev/null
@@ -1,2 +0,0 @@
-class MocktailDesigner < DrinkDesigner
-end
diff --git a/activerecord/test/models/molecule.rb b/activerecord/test/models/molecule.rb
index 26870c8f88..7da08a85c4 100644
--- a/activerecord/test/models/molecule.rb
+++ b/activerecord/test/models/molecule.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Molecule < ActiveRecord::Base
   belongs_to :liquid
   has_many :electrons
diff --git a/activerecord/test/models/movie.rb b/activerecord/test/models/movie.rb
index 0302abad1e..fa2ea900c7 100644
--- a/activerecord/test/models/movie.rb
+++ b/activerecord/test/models/movie.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Movie < ActiveRecord::Base
   self.primary_key = "movieid"
 
diff --git a/activerecord/test/models/node.rb b/activerecord/test/models/node.rb
index 07dd2dbccb..ae46c76b46 100644
--- a/activerecord/test/models/node.rb
+++ b/activerecord/test/models/node.rb
@@ -1,5 +1,7 @@
+# frozen_string_literal: true
+
 class Node < ActiveRecord::Base
   belongs_to :tree, touch: true
-  belongs_to :parent,   class_name: 'Node', touch: true, optional: true
-  has_many   :children, class_name: 'Node', foreign_key: :parent_id, dependent: :destroy
+  belongs_to :parent,   class_name: "Node", touch: true, optional: true
+  has_many   :children, class_name: "Node", foreign_key: :parent_id, dependent: :destroy
 end
diff --git a/activerecord/test/models/non_primary_key.rb b/activerecord/test/models/non_primary_key.rb
new file mode 100644
index 0000000000..e954375989
--- /dev/null
+++ b/activerecord/test/models/non_primary_key.rb
@@ -0,0 +1,4 @@
+# frozen_string_literal: true
+
+class NonPrimaryKey < ActiveRecord::Base
+end
diff --git a/activerecord/test/models/notification.rb b/activerecord/test/models/notification.rb
index 82edc64b68..3f8728af5e 100644
--- a/activerecord/test/models/notification.rb
+++ b/activerecord/test/models/notification.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Notification < ActiveRecord::Base
   validates_presence_of :message
 end
diff --git a/activerecord/test/models/numeric_data.rb b/activerecord/test/models/numeric_data.rb
new file mode 100644
index 0000000000..666e1a5778
--- /dev/null
+++ b/activerecord/test/models/numeric_data.rb
@@ -0,0 +1,10 @@
+# frozen_string_literal: true
+
+class NumericData < ActiveRecord::Base
+  self.table_name = "numeric_data"
+  # Decimal columns with 0 scale being automatically treated as integers
+  # is deprecated, and will be removed in a future version of Rails.
+  attribute :world_population, :big_integer
+  attribute :my_house_population, :big_integer
+  attribute :atoms_in_universe, :big_integer
+end
diff --git a/activerecord/test/models/order.rb b/activerecord/test/models/order.rb
index e838c0b70d..36866b398f 100644
--- a/activerecord/test/models/order.rb
+++ b/activerecord/test/models/order.rb
@@ -1,4 +1,6 @@
+# frozen_string_literal: true
+
 class Order < ActiveRecord::Base
-  belongs_to :billing, :class_name => 'Customer', :foreign_key => 'billing_customer_id'
-  belongs_to :shipping, :class_name => 'Customer', :foreign_key => 'shipping_customer_id'
+  belongs_to :billing, class_name: "Customer", foreign_key: "billing_customer_id"
+  belongs_to :shipping, class_name: "Customer", foreign_key: "shipping_customer_id"
 end
diff --git a/activerecord/test/models/organization.rb b/activerecord/test/models/organization.rb
index f3e92f3067..099e7e38e0 100644
--- a/activerecord/test/models/organization.rb
+++ b/activerecord/test/models/organization.rb
@@ -1,14 +1,16 @@
+# frozen_string_literal: true
+
 class Organization < ActiveRecord::Base
   has_many :member_details
-  has_many :members, :through => :member_details
+  has_many :members, through: :member_details
 
-  has_many :authors, :primary_key => :name
-  has_many :author_essay_categories, :through => :authors, :source => :essay_categories
+  has_many :authors, primary_key: :name
+  has_many :author_essay_categories, through: :authors, source: :essay_categories
 
-  has_one :author, :primary_key => :name
-  has_one :author_owned_essay_category, :through => :author, :source => :owned_essay_category
+  has_one :author, primary_key: :name
+  has_one :author_owned_essay_category, through: :author, source: :owned_essay_category
 
-  has_many :posts, :through => :author, :source => :posts
+  has_many :posts, through: :author, source: :posts
 
-  scope :clubs, -> { from('clubs') }
+  scope :clubs, -> { from("clubs") }
 end
diff --git a/activerecord/test/models/other_dog.rb b/activerecord/test/models/other_dog.rb
new file mode 100644
index 0000000000..a0fda5ae1b
--- /dev/null
+++ b/activerecord/test/models/other_dog.rb
@@ -0,0 +1,7 @@
+# frozen_string_literal: true
+
+require_dependency "models/arunit2_model"
+
+class OtherDog < ARUnit2Model
+  self.table_name = "dogs"
+end
diff --git a/activerecord/test/models/owner.rb b/activerecord/test/models/owner.rb
index ce8242cf2f..5fa50d9918 100644
--- a/activerecord/test/models/owner.rb
+++ b/activerecord/test/models/owner.rb
@@ -1,19 +1,21 @@
+# frozen_string_literal: true
+
 class Owner < ActiveRecord::Base
   self.primary_key = :owner_id
-  has_many :pets, -> { order 'pets.name desc' }
+  has_many :pets, -> { order "pets.name desc" }
   has_many :toys, through: :pets
   has_many :persons, through: :pets
 
-  belongs_to :last_pet, class_name: 'Pet'
+  belongs_to :last_pet, class_name: "Pet"
   scope :including_last_pet, -> {
-    select(%q[
+    select('
       owners.*, (
         select p.pet_id from pets p
         where p.owner_id = owners.owner_id
         order by p.name desc
         limit 1
       ) as last_pet_id
-    ]).includes(:last_pet)
+    ').includes(:last_pet)
   }
 
   after_commit :execute_blocks
diff --git a/activerecord/test/models/parrot.rb b/activerecord/test/models/parrot.rb
index ddc9dcaf29..ba9ddb8c6a 100644
--- a/activerecord/test/models/parrot.rb
+++ b/activerecord/test/models/parrot.rb
@@ -1,23 +1,30 @@
+# frozen_string_literal: true
+
 class Parrot < ActiveRecord::Base
   self.inheritance_column = :parrot_sti_class
 
   has_and_belongs_to_many :pirates
   has_and_belongs_to_many :treasures
-  has_many :loots, :as => :looter
+  has_many :loots, as: :looter
   alias_attribute :title, :name
 
   validates_presence_of :name
 
-  attr_accessor :cancel_save_from_callback
-  before_save :cancel_save_callback_method, :if => :cancel_save_from_callback
+  attribute :cancel_save_from_callback
+  before_save :cancel_save_callback_method, if: :cancel_save_from_callback
   def cancel_save_callback_method
     throw(:abort)
   end
+
+  before_update :increment_updated_count
+  def increment_updated_count
+    self.updated_count += 1
+  end
 end
 
 class LiveParrot < Parrot
 end
 
 class DeadParrot < Parrot
-  belongs_to :killer, :class_name => 'Pirate', foreign_key: :killer_id
+  belongs_to :killer, class_name: "Pirate", foreign_key: :killer_id
 end
diff --git a/activerecord/test/models/person.rb b/activerecord/test/models/person.rb
index a4a9c6b0d4..5cba1e440e 100644
--- a/activerecord/test/models/person.rb
+++ b/activerecord/test/models/person.rb
@@ -1,73 +1,74 @@
+# frozen_string_literal: true
+
 class Person < ActiveRecord::Base
   has_many :readers
   has_many :secure_readers
   has_one  :reader
 
-  has_many :posts, :through => :readers
-  has_many :secure_posts, :through => :secure_readers
-  has_many :posts_with_no_comments, -> { includes(:comments).where('comments.id is null').references(:comments) },
-                                    :through => :readers, :source => :post
+  has_many :posts, through: :readers
+  has_many :secure_posts, through: :secure_readers
+  has_many :posts_with_no_comments, -> { includes(:comments).where("comments.id is null").references(:comments) },
+                                    through: :readers, source: :post
 
-  has_many :friendships, foreign_key: 'friend_id'
+  has_many :friendships, foreign_key: "friend_id"
   # friends_too exists to test a bug, and probably shouldn't be used elsewhere
-  has_many :friends_too, foreign_key: 'friend_id', class_name: 'Friendship'
+  has_many :friends_too, foreign_key: "friend_id", class_name: "Friendship"
   has_many :followers, through: :friendships
 
   has_many :references
   has_many :bad_references
-  has_many :fixed_bad_references, -> { where :favourite => true }, :class_name => 'BadReference'
-  has_one  :favourite_reference, -> { where 'favourite=?', true }, :class_name => 'Reference'
-  has_many :posts_with_comments_sorted_by_comment_id, -> { includes(:comments).order('comments.id') }, :through => :readers, :source => :post
+  has_many :fixed_bad_references, -> { where favourite: true }, class_name: "BadReference"
+  has_one  :favourite_reference, -> { where "favourite=?", true }, class_name: "Reference"
+  has_many :posts_with_comments_sorted_by_comment_id, -> { includes(:comments).order("comments.id") }, through: :readers, source: :post
   has_many :first_posts, -> { where(id: [1, 2]) }, through: :readers
 
-  has_many :jobs, :through => :references
-  has_many :jobs_with_dependent_destroy,    :source => :job, :through => :references, :dependent => :destroy
-  has_many :jobs_with_dependent_delete_all, :source => :job, :through => :references, :dependent => :delete_all
-  has_many :jobs_with_dependent_nullify,    :source => :job, :through => :references, :dependent => :nullify
+  has_many :jobs, through: :references
+  has_many :jobs_with_dependent_destroy,    source: :job, through: :references, dependent: :destroy
+  has_many :jobs_with_dependent_delete_all, source: :job, through: :references, dependent: :delete_all
+  has_many :jobs_with_dependent_nullify,    source: :job, through: :references, dependent: :nullify
 
-  belongs_to :primary_contact, :class_name => 'Person'
-  has_many :agents, :class_name => 'Person', :foreign_key => 'primary_contact_id'
-  has_many :agents_of_agents, :through => :agents, :source => :agents
-  belongs_to :number1_fan, :class_name => 'Person'
+  belongs_to :primary_contact, class_name: "Person"
+  has_many :agents, class_name: "Person", foreign_key: "primary_contact_id"
+  has_many :agents_of_agents, through: :agents, source: :agents
+  belongs_to :number1_fan, class_name: "Person"
 
-  has_many :personal_legacy_things, :dependent => :destroy
+  has_many :personal_legacy_things, dependent: :destroy
 
-  has_many :agents_posts,         :through => :agents,       :source => :posts
-  has_many :agents_posts_authors, :through => :agents_posts, :source => :author
+  has_many :agents_posts,         through: :agents,       source: :posts
+  has_many :agents_posts_authors, through: :agents_posts, source: :author
   has_many :essays, primary_key: "first_name", foreign_key: "writer_id"
 
-  scope :males,   -> { where(:gender => 'M') }
+  scope :males,   -> { where(gender: "M") }
 end
 
 class PersonWithDependentDestroyJobs < ActiveRecord::Base
-  self.table_name = 'people'
+  self.table_name = "people"
 
-  has_many :references, :foreign_key => :person_id
-  has_many :jobs, :source => :job, :through => :references, :dependent => :destroy
+  has_many :references, foreign_key: :person_id
+  has_many :jobs, source: :job, through: :references, dependent: :destroy
 end
 
 class PersonWithDependentDeleteAllJobs < ActiveRecord::Base
-  self.table_name = 'people'
+  self.table_name = "people"
 
-  has_many :references, :foreign_key => :person_id
-  has_many :jobs, :source => :job, :through => :references, :dependent => :delete_all
+  has_many :references, foreign_key: :person_id
+  has_many :jobs, source: :job, through: :references, dependent: :delete_all
 end
 
 class PersonWithDependentNullifyJobs < ActiveRecord::Base
-  self.table_name = 'people'
+  self.table_name = "people"
 
-  has_many :references, :foreign_key => :person_id
-  has_many :jobs, :source => :job, :through => :references, :dependent => :nullify
+  has_many :references, foreign_key: :person_id
+  has_many :jobs, source: :job, through: :references, dependent: :nullify
 end
 
-
 class LoosePerson < ActiveRecord::Base
-  self.table_name = 'people'
+  self.table_name = "people"
   self.abstract_class = true
 
-  has_one    :best_friend,    :class_name => 'LoosePerson', :foreign_key => :best_friend_id
-  belongs_to :best_friend_of, :class_name => 'LoosePerson', :foreign_key => :best_friend_of_id
-  has_many   :best_friends,   :class_name => 'LoosePerson', :foreign_key => :best_friend_id
+  has_one    :best_friend,    class_name: "LoosePerson", foreign_key: :best_friend_id
+  belongs_to :best_friend_of, class_name: "LoosePerson", foreign_key: :best_friend_of_id
+  has_many   :best_friends,   class_name: "LoosePerson", foreign_key: :best_friend_id
 
   accepts_nested_attributes_for :best_friend, :best_friend_of, :best_friends
 end
@@ -75,11 +76,11 @@ end
 class LooseDescendant < LoosePerson; end
 
 class TightPerson < ActiveRecord::Base
-  self.table_name = 'people'
+  self.table_name = "people"
 
-  has_one    :best_friend,    :class_name => 'TightPerson', :foreign_key => :best_friend_id
-  belongs_to :best_friend_of, :class_name => 'TightPerson', :foreign_key => :best_friend_of_id
-  has_many   :best_friends,   :class_name => 'TightPerson', :foreign_key => :best_friend_id
+  has_one    :best_friend,    class_name: "TightPerson", foreign_key: :best_friend_id
+  belongs_to :best_friend_of, class_name: "TightPerson", foreign_key: :best_friend_of_id
+  has_many   :best_friends,   class_name: "TightPerson", foreign_key: :best_friend_id
 
   accepts_nested_attributes_for :best_friend, :best_friend_of, :best_friends
 end
@@ -87,56 +88,56 @@ end
 class TightDescendant < TightPerson; end
 
 class RichPerson < ActiveRecord::Base
-  self.table_name = 'people'
+  self.table_name = "people"
 
-  has_and_belongs_to_many :treasures, :join_table => 'peoples_treasures'
+  has_and_belongs_to_many :treasures, join_table: "peoples_treasures"
 
   before_validation :run_before_create, on: :create
   before_validation :run_before_validation
 
   private
 
-  def run_before_create
-    self.first_name = first_name.to_s + 'run_before_create'
-  end
+    def run_before_create
+      self.first_name = first_name.to_s + "run_before_create"
+    end
 
-  def run_before_validation
-    self.first_name = first_name.to_s + 'run_before_validation'
-  end
+    def run_before_validation
+      self.first_name = first_name.to_s + "run_before_validation"
+    end
 end
 
 class NestedPerson < ActiveRecord::Base
-  self.table_name = 'people'
+  self.table_name = "people"
 
-  has_one :best_friend, :class_name => 'NestedPerson', :foreign_key => :best_friend_id
-  accepts_nested_attributes_for :best_friend, :update_only => true
+  has_one :best_friend, class_name: "NestedPerson", foreign_key: :best_friend_id
+  accepts_nested_attributes_for :best_friend, update_only: true
 
   def comments=(new_comments)
     raise RuntimeError
   end
 
   def best_friend_first_name=(new_name)
-    assign_attributes({ :best_friend_attributes => { :first_name => new_name } })
+    assign_attributes(best_friend_attributes: { first_name: new_name })
   end
 end
 
 class Insure
   INSURES = %W{life annuality}
 
-  def self.load mask
+  def self.load(mask)
     INSURES.select do |insure|
       (1 << INSURES.index(insure)) & mask.to_i > 0
     end
   end
 
-  def self.dump insures
+  def self.dump(insures)
     numbers = insures.map { |insure| INSURES.index(insure) }
     numbers.inject(0) { |sum, n| sum + (1 << n) }
   end
 end
 
 class SerializedPerson < ActiveRecord::Base
-  self.table_name = 'people'
+  self.table_name = "people"
 
   serialize :insures, Insure
 end
diff --git a/activerecord/test/models/personal_legacy_thing.rb b/activerecord/test/models/personal_legacy_thing.rb
index a7ee3a0bca..ed8b70cfcc 100644
--- a/activerecord/test/models/personal_legacy_thing.rb
+++ b/activerecord/test/models/personal_legacy_thing.rb
@@ -1,4 +1,6 @@
+# frozen_string_literal: true
+
 class PersonalLegacyThing < ActiveRecord::Base
   self.locking_column = :version
-  belongs_to :person, :counter_cache => true
+  belongs_to :person, counter_cache: true
 end
diff --git a/activerecord/test/models/pet.rb b/activerecord/test/models/pet.rb
index 53489fa1b3..9bda2109e6 100644
--- a/activerecord/test/models/pet.rb
+++ b/activerecord/test/models/pet.rb
@@ -1,12 +1,14 @@
+# frozen_string_literal: true
+
 class Pet < ActiveRecord::Base
   attr_accessor :current_user
 
   self.primary_key = :pet_id
-  belongs_to :owner, :touch => true
+  belongs_to :owner, touch: true
   has_many :toys
   has_many :pet_treasures
   has_many :treasures, through: :pet_treasures
-  has_many :persons, through: :treasures, source: :looter, source_type: 'Person'
+  has_many :persons, through: :treasures, source: :looter, source_type: "Person"
 
   class << self
     attr_accessor :after_destroy_output
diff --git a/activerecord/test/models/pet_treasure.rb b/activerecord/test/models/pet_treasure.rb
index 1fe7807ffe..47b9f57fad 100644
--- a/activerecord/test/models/pet_treasure.rb
+++ b/activerecord/test/models/pet_treasure.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class PetTreasure < ActiveRecord::Base
   self.table_name = "pets_treasures"
 
diff --git a/activerecord/test/models/pirate.rb b/activerecord/test/models/pirate.rb
index 30545bdcd7..c8617d1cfe 100644
--- a/activerecord/test/models/pirate.rb
+++ b/activerecord/test/models/pirate.rb
@@ -1,47 +1,49 @@
+# frozen_string_literal: true
+
 class Pirate < ActiveRecord::Base
-  belongs_to :parrot, :validate => true
-  belongs_to :non_validated_parrot, :class_name => 'Parrot'
-  has_and_belongs_to_many :parrots, -> { order('parrots.id ASC') }, :validate => true
-  has_and_belongs_to_many :non_validated_parrots, :class_name => 'Parrot'
-  has_and_belongs_to_many :parrots_with_method_callbacks, :class_name => "Parrot",
-    :before_add    => :log_before_add,
-    :after_add     => :log_after_add,
-    :before_remove => :log_before_remove,
-    :after_remove  => :log_after_remove
-  has_and_belongs_to_many :parrots_with_proc_callbacks, :class_name => "Parrot",
-    :before_add    => proc {|p,pa| p.ship_log << "before_adding_proc_parrot_#{pa.id || '<new>'}"},
-    :after_add     => proc {|p,pa| p.ship_log << "after_adding_proc_parrot_#{pa.id || '<new>'}"},
-    :before_remove => proc {|p,pa| p.ship_log << "before_removing_proc_parrot_#{pa.id}"},
-    :after_remove  => proc {|p,pa| p.ship_log << "after_removing_proc_parrot_#{pa.id}"}
+  belongs_to :parrot, validate: true
+  belongs_to :non_validated_parrot, class_name: "Parrot"
+  has_and_belongs_to_many :parrots, -> { order("parrots.id ASC") }, validate: true
+  has_and_belongs_to_many :non_validated_parrots, class_name: "Parrot"
+  has_and_belongs_to_many :parrots_with_method_callbacks, class_name: "Parrot",
+    before_add: :log_before_add,
+    after_add: :log_after_add,
+    before_remove: :log_before_remove,
+    after_remove: :log_after_remove
+  has_and_belongs_to_many :parrots_with_proc_callbacks, class_name: "Parrot",
+    before_add: proc { |p, pa| p.ship_log << "before_adding_proc_parrot_#{pa.id || '<new>'}" },
+    after_add: proc { |p, pa| p.ship_log << "after_adding_proc_parrot_#{pa.id || '<new>'}" },
+    before_remove: proc { |p, pa| p.ship_log << "before_removing_proc_parrot_#{pa.id}" },
+    after_remove: proc { |p, pa| p.ship_log << "after_removing_proc_parrot_#{pa.id}" }
   has_and_belongs_to_many :autosaved_parrots, class_name: "Parrot", autosave: true
 
-  has_many :treasures, :as => :looter
-  has_many :treasure_estimates, :through => :treasures, :source => :price_estimates
+  has_many :treasures, as: :looter
+  has_many :treasure_estimates, through: :treasures, source: :price_estimates
 
   has_one :ship
-  has_one :update_only_ship, :class_name => 'Ship'
-  has_one :non_validated_ship, :class_name => 'Ship'
-  has_many :birds, -> { order('birds.id ASC') }
-  has_many :birds_with_method_callbacks, :class_name => "Bird",
-    :before_add    => :log_before_add,
-    :after_add     => :log_after_add,
-    :before_remove => :log_before_remove,
-    :after_remove  => :log_after_remove
-  has_many :birds_with_proc_callbacks, :class_name => "Bird",
-    :before_add     => proc {|p,b| p.ship_log << "before_adding_proc_bird_#{b.id || '<new>'}"},
-    :after_add      => proc {|p,b| p.ship_log << "after_adding_proc_bird_#{b.id || '<new>'}"},
-    :before_remove  => proc {|p,b| p.ship_log << "before_removing_proc_bird_#{b.id}"},
-    :after_remove   => proc {|p,b| p.ship_log << "after_removing_proc_bird_#{b.id}"}
-  has_many :birds_with_reject_all_blank, :class_name => "Bird"
-
-  has_one :foo_bulb, -> { where :name => 'foo' }, :foreign_key => :car_id, :class_name => "Bulb"
-
-  accepts_nested_attributes_for :parrots, :birds, :allow_destroy => true, :reject_if => proc(&:empty?)
-  accepts_nested_attributes_for :ship, :allow_destroy => true, :reject_if => proc(&:empty?)
-  accepts_nested_attributes_for :update_only_ship, :update_only => true
+  has_one :update_only_ship, class_name: "Ship"
+  has_one :non_validated_ship, class_name: "Ship"
+  has_many :birds, -> { order("birds.id ASC") }
+  has_many :birds_with_method_callbacks, class_name: "Bird",
+    before_add: :log_before_add,
+    after_add: :log_after_add,
+    before_remove: :log_before_remove,
+    after_remove: :log_after_remove
+  has_many :birds_with_proc_callbacks, class_name: "Bird",
+    before_add: proc { |p, b| p.ship_log << "before_adding_proc_bird_#{b.id || '<new>'}" },
+    after_add: proc { |p, b| p.ship_log << "after_adding_proc_bird_#{b.id || '<new>'}" },
+    before_remove: proc { |p, b| p.ship_log << "before_removing_proc_bird_#{b.id}" },
+    after_remove: proc { |p, b| p.ship_log << "after_removing_proc_bird_#{b.id}" }
+  has_many :birds_with_reject_all_blank, class_name: "Bird"
+
+  has_one :foo_bulb, -> { where name: "foo" }, foreign_key: :car_id, class_name: "Bulb"
+
+  accepts_nested_attributes_for :parrots, :birds, allow_destroy: true, reject_if: proc(&:empty?)
+  accepts_nested_attributes_for :ship, allow_destroy: true, reject_if: proc(&:empty?)
+  accepts_nested_attributes_for :update_only_ship, update_only: true
   accepts_nested_attributes_for :parrots_with_method_callbacks, :parrots_with_proc_callbacks,
-    :birds_with_method_callbacks, :birds_with_proc_callbacks, :allow_destroy => true
-  accepts_nested_attributes_for :birds_with_reject_all_blank, :reject_if => :all_blank
+    :birds_with_method_callbacks, :birds_with_proc_callbacks, allow_destroy: true
+  accepts_nested_attributes_for :birds_with_reject_all_blank, reject_if: :all_blank
 
   validates_presence_of :catchphrase
 
@@ -50,11 +52,11 @@ class Pirate < ActiveRecord::Base
   end
 
   def reject_empty_ships_on_create(attributes)
-    attributes.delete('_reject_me_if_new').present? && !persisted?
+    attributes.delete("_reject_me_if_new").present? && !persisted?
   end
 
   attr_accessor :cancel_save_from_callback, :parrots_limit
-  before_save :cancel_save_callback_method, :if => :cancel_save_from_callback
+  before_save :cancel_save_callback_method, if: :cancel_save_from_callback
   def cancel_save_callback_method
     throw(:abort)
   end
@@ -82,11 +84,11 @@ class Pirate < ActiveRecord::Base
 end
 
 class DestructivePirate < Pirate
-  has_one :dependent_ship, :class_name => 'Ship', :foreign_key => :pirate_id, :dependent => :destroy
+  has_one :dependent_ship, class_name: "Ship", foreign_key: :pirate_id, dependent: :destroy
 end
 
 class FamousPirate < ActiveRecord::Base
-  self.table_name = 'pirates'
+  self.table_name = "pirates"
   has_many :famous_ships
   validates_presence_of :catchphrase, on: :conference
 end
diff --git a/activerecord/test/models/possession.rb b/activerecord/test/models/possession.rb
index ddf759113b..9b843e1525 100644
--- a/activerecord/test/models/possession.rb
+++ b/activerecord/test/models/possession.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Possession < ActiveRecord::Base
-  self.table_name = 'having'
+  self.table_name = "having"
 end
diff --git a/activerecord/test/models/post.rb b/activerecord/test/models/post.rb
index bf3079a1df..780a2c17f5 100644
--- a/activerecord/test/models/post.rb
+++ b/activerecord/test/models/post.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Post < ActiveRecord::Base
   class CategoryPost < ActiveRecord::Base
     self.table_name = "categories_posts"
@@ -7,36 +9,38 @@ class Post < ActiveRecord::Base
 
   module NamedExtension
     def author
-      'lifo'
+      "lifo"
     end
   end
 
   module NamedExtension2
     def greeting
-      "hello"
+      "hullo"
     end
   end
 
   scope :containing_the_letter_a, -> { where("body LIKE '%a%'") }
   scope :titled_with_an_apostrophe, -> { where("title LIKE '%''%'") }
-  scope :ranked_by_comments,      -> { order("comments_count DESC") }
+  scope :ranked_by_comments, -> { order(arel_attribute(:comments_count).desc) }
 
-  scope :limit_by, lambda {|l| limit(l) }
+  scope :limit_by, lambda { |l| limit(l) }
+  scope :locked, -> { lock }
 
   belongs_to :author
+  belongs_to :readonly_author, -> { readonly }, class_name: "Author", foreign_key: :author_id
 
-  belongs_to :author_with_posts, -> { includes(:posts) }, :class_name => "Author", :foreign_key => :author_id
-  belongs_to :author_with_address, -> { includes(:author_address) }, :class_name => "Author", :foreign_key => :author_id
+  belongs_to :author_with_posts, -> { includes(:posts) }, class_name: "Author", foreign_key: :author_id
+  belongs_to :author_with_address, -> { includes(:author_address) }, class_name: "Author", foreign_key: :author_id
 
   def first_comment
     super.body
   end
-  has_one :first_comment, -> { order('id ASC') }, :class_name => 'Comment'
-  has_one :last_comment, -> { order('id desc') }, :class_name => 'Comment'
+  has_one :first_comment, -> { order("id ASC") }, class_name: "Comment"
+  has_one :last_comment, -> { order("id desc") }, class_name: "Comment"
 
-  scope :with_special_comments, -> { joins(:comments).where(:comments => {:type => 'SpecialComment'}) }
-  scope :with_very_special_comments, -> { joins(:comments).where(:comments => {:type => 'VerySpecialComment'}) }
-  scope :with_post, ->(post_id) { joins(:comments).where(:comments => { :post_id => post_id }) }
+  scope :with_special_comments, -> { joins(:comments).where(comments: { type: "SpecialComment" }) }
+  scope :with_very_special_comments, -> { joins(:comments).where(comments: { type: "VerySpecialComment" }) }
+  scope :with_post, ->(post_id) { joins(:comments).where(comments: { post_id: post_id }) }
 
   scope :with_comments, -> { preload(:comments) }
   scope :with_tags, -> { preload(:taggings) }
@@ -46,7 +50,7 @@ class Post < ActiveRecord::Base
 
   scope :typographically_interesting, -> { containing_the_letter_a.or(titled_with_an_apostrophe) }
 
-  has_many   :comments do
+  has_many :comments do
     def find_most_recent
       order("id DESC").first
     end
@@ -58,6 +62,10 @@ class Post < ActiveRecord::Base
     def the_association
       proxy_association
     end
+
+    def with_content(content)
+      self.detect { |comment| comment.body == content }
+    end
   end
 
   has_many :comments_with_extend, extend: NamedExtension, class_name: "Comment", foreign_key: "post_id" do
@@ -68,92 +76,93 @@ class Post < ActiveRecord::Base
 
   has_many :comments_with_extend_2, extend: [NamedExtension, NamedExtension2], class_name: "Comment", foreign_key: "post_id"
 
-  has_many :author_favorites, :through => :author
-  has_many :author_categorizations, :through => :author, :source => :categorizations
-  has_many :author_addresses, :through => :author
+  has_many :author_favorites, through: :author
+  has_many :author_categorizations, through: :author, source: :categorizations
+  has_many :author_addresses, through: :author
   has_many :author_address_extra_with_address,
     through: :author_with_address,
     source: :author_address_extra
 
   has_one  :very_special_comment
-  has_one  :very_special_comment_with_post, -> { includes(:post) }, :class_name => "VerySpecialComment"
-  has_one :very_special_comment_with_post_with_joins, -> { joins(:post).order('posts.id') }, class_name: "VerySpecialComment"
+  has_one  :very_special_comment_with_post, -> { includes(:post) }, class_name: "VerySpecialComment"
+  has_one :very_special_comment_with_post_with_joins, -> { joins(:post).order("posts.id") }, class_name: "VerySpecialComment"
   has_many :special_comments
-  has_many :nonexistent_comments, -> { where 'comments.id < 0' }, :class_name => 'Comment'
+  has_many :nonexistent_comments, -> { where "comments.id < 0" }, class_name: "Comment"
 
-  has_many :special_comments_ratings, :through => :special_comments, :source => :ratings
-  has_many :special_comments_ratings_taggings, :through => :special_comments_ratings, :source => :taggings
+  has_many :special_comments_ratings, through: :special_comments, source: :ratings
+  has_many :special_comments_ratings_taggings, through: :special_comments_ratings, source: :taggings
 
-  has_many :category_posts, :class_name => 'CategoryPost'
+  has_many :category_posts, class_name: "CategoryPost"
   has_many :scategories, through: :category_posts, source: :category
   has_and_belongs_to_many :categories
-  has_and_belongs_to_many :special_categories, :join_table => "categories_posts", :association_foreign_key => 'category_id'
+  has_and_belongs_to_many :special_categories, join_table: "categories_posts", association_foreign_key: "category_id"
 
-  has_many :taggings, :as => :taggable, :counter_cache => :tags_count
-  has_many :tags, :through => :taggings do
+  has_many :taggings, as: :taggable, counter_cache: :tags_count
+  has_many :tags, through: :taggings do
     def add_joins_and_select
-      select('tags.*, authors.id as author_id')
-        .joins('left outer join posts on taggings.taggable_id = posts.id left outer join authors on posts.author_id = authors.id')
+      select("tags.*, authors.id as author_id")
+        .joins("left outer join posts on taggings.taggable_id = posts.id left outer join authors on posts.author_id = authors.id")
         .to_a
     end
   end
 
-  has_many :taggings_with_delete_all, :class_name => 'Tagging', :as => :taggable, :dependent => :delete_all, counter_cache: :taggings_with_delete_all_count
-  has_many :taggings_with_destroy, :class_name => 'Tagging', :as => :taggable, :dependent => :destroy, counter_cache: :taggings_with_destroy_count
+  has_many :taggings_with_delete_all, class_name: "Tagging", as: :taggable, dependent: :delete_all, counter_cache: :taggings_with_delete_all_count
+  has_many :taggings_with_destroy, class_name: "Tagging", as: :taggable, dependent: :destroy, counter_cache: :taggings_with_destroy_count
 
-  has_many :tags_with_destroy, :through => :taggings, :source => :tag, :dependent => :destroy, counter_cache: :tags_with_destroy_count
-  has_many :tags_with_nullify, :through => :taggings, :source => :tag, :dependent => :nullify, counter_cache: :tags_with_nullify_count
+  has_many :tags_with_destroy, through: :taggings, source: :tag, dependent: :destroy, counter_cache: :tags_with_destroy_count
+  has_many :tags_with_nullify, through: :taggings, source: :tag, dependent: :nullify, counter_cache: :tags_with_nullify_count
 
-  has_many :misc_tags, -> { where :tags => { :name => 'Misc' } }, :through => :taggings, :source => :tag
-  has_many :funky_tags, :through => :taggings, :source => :tag
-  has_many :super_tags, :through => :taggings
-  has_many :tags_with_primary_key, :through => :taggings, :source => :tag_with_primary_key
-  has_one :tagging, :as => :taggable
+  has_many :misc_tags, -> { where tags: { name: "Misc" } }, through: :taggings, source: :tag
+  has_many :funky_tags, through: :taggings, source: :tag
+  has_many :super_tags, through: :taggings
+  has_many :ordered_tags, through: :taggings
+  has_many :tags_with_primary_key, through: :taggings, source: :tag_with_primary_key
+  has_one :tagging, as: :taggable
 
-  has_many :first_taggings, -> { where :taggings => { :comment => 'first' } }, :as => :taggable, :class_name => 'Tagging'
-  has_many :first_blue_tags, -> { where :tags => { :name => 'Blue' } }, :through => :first_taggings, :source => :tag
+  has_many :first_taggings, -> { where taggings: { comment: "first" } }, as: :taggable, class_name: "Tagging"
+  has_many :first_blue_tags, -> { where tags: { name: "Blue" } }, through: :first_taggings, source: :tag
 
-  has_many :first_blue_tags_2, -> { where :taggings => { :comment => 'first' } }, :through => :taggings, :source => :blue_tag
+  has_many :first_blue_tags_2, -> { where taggings: { comment: "first" } }, through: :taggings, source: :blue_tag
 
-  has_many :invalid_taggings, -> { where 'taggings.id < 0' }, :as => :taggable, :class_name => "Tagging"
-  has_many :invalid_tags, :through => :invalid_taggings, :source => :tag
+  has_many :invalid_taggings, -> { where "taggings.id < 0" }, as: :taggable, class_name: "Tagging"
+  has_many :invalid_tags, through: :invalid_taggings, source: :tag
 
-  has_many :categorizations, :foreign_key => :category_id
-  has_many :authors, :through => :categorizations
+  has_many :categorizations, foreign_key: :category_id
+  has_many :authors, through: :categorizations
 
-  has_many :categorizations_using_author_id, :primary_key => :author_id, :foreign_key => :post_id, :class_name => 'Categorization'
-  has_many :authors_using_author_id, :through => :categorizations_using_author_id, :source => :author
+  has_many :categorizations_using_author_id, primary_key: :author_id, foreign_key: :post_id, class_name: "Categorization"
+  has_many :authors_using_author_id, through: :categorizations_using_author_id, source: :author
 
-  has_many :taggings_using_author_id, :primary_key => :author_id, :as => :taggable, :class_name => 'Tagging'
-  has_many :tags_using_author_id, :through => :taggings_using_author_id, :source => :tag
+  has_many :taggings_using_author_id, primary_key: :author_id, as: :taggable, class_name: "Tagging"
+  has_many :tags_using_author_id, through: :taggings_using_author_id, source: :tag
 
-  has_many :images, :as => :imageable, :foreign_key => :imageable_identifier, :foreign_type => :imageable_class
-  has_one :main_image, :as => :imageable, :foreign_key => :imageable_identifier, :foreign_type => :imageable_class, :class_name => 'Image'
+  has_many :images, as: :imageable, foreign_key: :imageable_identifier, foreign_type: :imageable_class
+  has_one :main_image, as: :imageable, foreign_key: :imageable_identifier, foreign_type: :imageable_class, class_name: "Image"
 
-  has_many :standard_categorizations, :class_name => 'Categorization', :foreign_key => :post_id
-  has_many :author_using_custom_pk,  :through => :standard_categorizations
-  has_many :authors_using_custom_pk, :through => :standard_categorizations
-  has_many :named_categories, :through => :standard_categorizations
+  has_many :standard_categorizations, class_name: "Categorization", foreign_key: :post_id
+  has_many :author_using_custom_pk,  through: :standard_categorizations
+  has_many :authors_using_custom_pk, through: :standard_categorizations
+  has_many :named_categories, through: :standard_categorizations
 
   has_many :readers
   has_many :secure_readers
-  has_many :readers_with_person, -> { includes(:person) }, :class_name => "Reader"
-  has_many :people, :through => :readers
-  has_many :single_people, :through => :readers
-  has_many :people_with_callbacks, :source=>:person, :through => :readers,
-              :before_add    => lambda {|owner, reader| log(:added,   :before, reader.first_name) },
-              :after_add     => lambda {|owner, reader| log(:added,   :after,  reader.first_name) },
-              :before_remove => lambda {|owner, reader| log(:removed, :before, reader.first_name) },
-              :after_remove  => lambda {|owner, reader| log(:removed, :after,  reader.first_name) }
-  has_many :skimmers, -> { where :skimmer => true }, :class_name => 'Reader'
-  has_many :impatient_people, :through => :skimmers, :source => :person
+  has_many :readers_with_person, -> { includes(:person) }, class_name: "Reader"
+  has_many :people, through: :readers
+  has_many :single_people, through: :readers
+  has_many :people_with_callbacks, source: :person, through: :readers,
+              before_add: lambda { |owner, reader| log(:added,   :before, reader.first_name) },
+              after_add: lambda { |owner, reader| log(:added,   :after,  reader.first_name) },
+              before_remove: lambda { |owner, reader| log(:removed, :before, reader.first_name) },
+              after_remove: lambda { |owner, reader| log(:removed, :after,  reader.first_name) }
+  has_many :skimmers, -> { where skimmer: true }, class_name: "Reader"
+  has_many :impatient_people, through: :skimmers, source: :person
 
   has_many :lazy_readers
-  has_many :lazy_readers_skimmers_or_not, -> { where(skimmer: [ true, false ]) }, :class_name => 'LazyReader'
+  has_many :lazy_readers_skimmers_or_not, -> { where(skimmer: [ true, false ]) }, class_name: "LazyReader"
 
-  has_many :lazy_people, :through => :lazy_readers, :source => :person
-  has_many :lazy_readers_unscope_skimmers, -> { skimmers_or_not }, :class_name => 'LazyReader'
-  has_many :lazy_people_unscope_skimmers, :through => :lazy_readers_unscope_skimmers, :source => :person
+  has_many :lazy_people, through: :lazy_readers, source: :person
+  has_many :lazy_readers_unscope_skimmers, -> { skimmers_or_not }, class_name: "LazyReader"
+  has_many :lazy_people_unscope_skimmers, through: :lazy_readers_unscope_skimmers, source: :person
 
   def self.top(limit)
     ranked_by_comments.limit_by(limit)
@@ -167,7 +176,7 @@ class Post < ActiveRecord::Base
     @log = []
   end
 
-  def self.log(message=nil, side=nil, new_record=nil)
+  def self.log(message = nil, side = nil, new_record = nil)
     return @log if message.nil?
     @log << [message, side, new_record]
   end
@@ -176,66 +185,76 @@ end
 class SpecialPost < Post; end
 
 class StiPost < Post
+  has_one :special_comment, class_name: "SpecialComment"
+end
+
+class AbstractStiPost < Post
   self.abstract_class = true
-  has_one :special_comment, :class_name => "SpecialComment"
 end
 
 class SubStiPost < StiPost
   self.table_name = Post.table_name
 end
 
+class SubAbstractStiPost < AbstractStiPost; end
+
 class FirstPost < ActiveRecord::Base
   self.inheritance_column = :disabled
-  self.table_name = 'posts'
-  default_scope { where(:id => 1) }
+  self.table_name = "posts"
+  default_scope { where(id: 1) }
 
-  has_many :comments, :foreign_key => :post_id
-  has_one  :comment,  :foreign_key => :post_id
+  has_many :comments, foreign_key: :post_id
+  has_one  :comment,  foreign_key: :post_id
+end
+
+class TaggedPost < Post
+  has_many :taggings, -> { rewhere(taggable_type: "TaggedPost") }, as: :taggable
+  has_many :tags, through: :taggings
 end
 
 class PostWithDefaultInclude < ActiveRecord::Base
   self.inheritance_column = :disabled
-  self.table_name = 'posts'
+  self.table_name = "posts"
   default_scope { includes(:comments) }
-  has_many :comments, :foreign_key => :post_id
+  has_many :comments, foreign_key: :post_id
 end
 
 class PostWithSpecialCategorization < Post
-  has_many :categorizations, :foreign_key => :post_id
-  default_scope { where(:type => 'PostWithSpecialCategorization').joins(:categorizations).where(:categorizations => { :special => true }) }
+  has_many :categorizations, foreign_key: :post_id
+  default_scope { where(type: "PostWithSpecialCategorization").joins(:categorizations).where(categorizations: { special: true }) }
 end
 
 class PostWithDefaultScope < ActiveRecord::Base
   self.inheritance_column = :disabled
-  self.table_name = 'posts'
+  self.table_name = "posts"
   default_scope { order(:title) }
 end
 
 class PostWithPreloadDefaultScope < ActiveRecord::Base
-  self.table_name = 'posts'
+  self.table_name = "posts"
 
-  has_many :readers, foreign_key: 'post_id'
+  has_many :readers, foreign_key: "post_id"
 
   default_scope { preload(:readers) }
 end
 
 class PostWithIncludesDefaultScope < ActiveRecord::Base
-  self.table_name = 'posts'
+  self.table_name = "posts"
 
-  has_many :readers, foreign_key: 'post_id'
+  has_many :readers, foreign_key: "post_id"
 
   default_scope { includes(:readers) }
 end
 
 class SpecialPostWithDefaultScope < ActiveRecord::Base
   self.inheritance_column = :disabled
-  self.table_name = 'posts'
-  default_scope { where(:id => [1, 5,6]) }
+  self.table_name = "posts"
+  default_scope { where(id: [1, 5, 6]) }
 end
 
 class PostThatLoadsCommentsInAnAfterSaveHook < ActiveRecord::Base
   self.inheritance_column = :disabled
-  self.table_name = 'posts'
+  self.table_name = "posts"
   has_many :comments, class_name: "CommentThatAutomaticallyAltersPostBody", foreign_key: :post_id
 
   after_save do |post|
@@ -245,7 +264,7 @@ end
 
 class PostWithAfterCreateCallback < ActiveRecord::Base
   self.inheritance_column = :disabled
-  self.table_name = 'posts'
+  self.table_name = "posts"
   has_many :comments, foreign_key: :post_id
 
   after_create do |post|
@@ -255,7 +274,7 @@ end
 
 class PostWithCommentWithDefaultScopeReferencesAssociation < ActiveRecord::Base
   self.inheritance_column = :disabled
-  self.table_name = 'posts'
+  self.table_name = "posts"
   has_many :comment_with_default_scope_references_associations, foreign_key: :post_id
   has_one :first_comment, class_name: "CommentWithDefaultScopeReferencesAssociation", foreign_key: :post_id
 end
@@ -265,8 +284,44 @@ class SerializedPost < ActiveRecord::Base
 end
 
 class ConditionalStiPost < Post
-  default_scope { where(title: 'Untitled') }
+  default_scope { where(title: "Untitled") }
 end
 
 class SubConditionalStiPost < ConditionalStiPost
 end
+
+class FakeKlass
+  extend ActiveRecord::Delegation::DelegateCache
+
+  inherited self
+
+  class << self
+    def connection
+      Post.connection
+    end
+
+    def table_name
+      "posts"
+    end
+
+    def attribute_alias?(name)
+      false
+    end
+
+    def sanitize_sql(sql)
+      sql
+    end
+
+    def sanitize_sql_for_order(sql)
+      sql
+    end
+
+    def arel_attribute(name, table)
+      table[name]
+    end
+
+    def enforce_raw_sql_whitelist(*args)
+      # noop
+    end
+  end
+end
diff --git a/activerecord/test/models/price_estimate.rb b/activerecord/test/models/price_estimate.rb
index d09e2a88a3..f1f88d8d8d 100644
--- a/activerecord/test/models/price_estimate.rb
+++ b/activerecord/test/models/price_estimate.rb
@@ -1,4 +1,6 @@
+# frozen_string_literal: true
+
 class PriceEstimate < ActiveRecord::Base
-  belongs_to :estimate_of, :polymorphic => true
+  belongs_to :estimate_of, polymorphic: true
   belongs_to :thing, polymorphic: true
 end
diff --git a/activerecord/test/models/professor.rb b/activerecord/test/models/professor.rb
index 7654eda0ef..abc23f40ff 100644
--- a/activerecord/test/models/professor.rb
+++ b/activerecord/test/models/professor.rb
@@ -1,4 +1,6 @@
-require_dependency 'models/arunit2_model'
+# frozen_string_literal: true
+
+require_dependency "models/arunit2_model"
 
 class Professor < ARUnit2Model
   has_and_belongs_to_many :courses
diff --git a/activerecord/test/models/project.rb b/activerecord/test/models/project.rb
index efa8246f1e..846cef625b 100644
--- a/activerecord/test/models/project.rb
+++ b/activerecord/test/models/project.rb
@@ -1,17 +1,19 @@
+# frozen_string_literal: true
+
 class Project < ActiveRecord::Base
   belongs_to :mentor
-  has_and_belongs_to_many :developers, -> { distinct.order 'developers.name desc, developers.id desc' }
-  has_and_belongs_to_many :readonly_developers, -> { readonly }, :class_name => "Developer"
-  has_and_belongs_to_many :non_unique_developers, -> { order 'developers.name desc, developers.id desc' }, :class_name => 'Developer'
-  has_and_belongs_to_many :limited_developers, -> { limit 1 }, :class_name => "Developer"
-  has_and_belongs_to_many :developers_named_david, -> { where("name = 'David'").distinct }, :class_name => "Developer"
-  has_and_belongs_to_many :developers_named_david_with_hash_conditions, -> { where(:name => 'David').distinct }, :class_name => "Developer"
-  has_and_belongs_to_many :salaried_developers, -> { where "salary > 0" }, :class_name => "Developer"
-  has_and_belongs_to_many :developers_with_callbacks, :class_name => "Developer", :before_add => Proc.new {|o, r| o.developers_log << "before_adding#{r.id || '<new>'}"},
-                            :after_add => Proc.new {|o, r| o.developers_log << "after_adding#{r.id || '<new>'}"},
-                            :before_remove => Proc.new {|o, r| o.developers_log << "before_removing#{r.id}"},
-                            :after_remove => Proc.new {|o, r| o.developers_log << "after_removing#{r.id}"}
-  has_and_belongs_to_many :well_payed_salary_groups, -> { group("developers.salary").having("SUM(salary) > 10000").select("SUM(salary) as salary") }, :class_name => "Developer"
+  has_and_belongs_to_many :developers, -> { distinct.order "developers.name desc, developers.id desc" }
+  has_and_belongs_to_many :readonly_developers, -> { readonly }, class_name: "Developer"
+  has_and_belongs_to_many :non_unique_developers, -> { order "developers.name desc, developers.id desc" }, class_name: "Developer"
+  has_and_belongs_to_many :limited_developers, -> { limit 1 }, class_name: "Developer"
+  has_and_belongs_to_many :developers_named_david, -> { where("name = 'David'").distinct }, class_name: "Developer"
+  has_and_belongs_to_many :developers_named_david_with_hash_conditions, -> { where(name: "David").distinct }, class_name: "Developer"
+  has_and_belongs_to_many :salaried_developers, -> { where "salary > 0" }, class_name: "Developer"
+  has_and_belongs_to_many :developers_with_callbacks, class_name: "Developer", before_add: Proc.new { |o, r| o.developers_log << "before_adding#{r.id || '<new>'}" },
+                            after_add: Proc.new { |o, r| o.developers_log << "after_adding#{r.id || '<new>'}" },
+                            before_remove: Proc.new { |o, r| o.developers_log << "before_removing#{r.id}" },
+                            after_remove: Proc.new { |o, r| o.developers_log << "after_removing#{r.id}" }
+  has_and_belongs_to_many :well_paid_salary_groups, -> { group("developers.salary").having("SUM(salary) > 10000").select("SUM(salary) as salary") }, class_name: "Developer"
   belongs_to :firm
   has_one :lead_developer, through: :firm, inverse_of: :contracted_projects
 
diff --git a/activerecord/test/models/publisher.rb b/activerecord/test/models/publisher.rb
index 0d4a7f9235..53677197c4 100644
--- a/activerecord/test/models/publisher.rb
+++ b/activerecord/test/models/publisher.rb
@@ -1,2 +1,4 @@
+# frozen_string_literal: true
+
 module Publisher
 end
diff --git a/activerecord/test/models/publisher/article.rb b/activerecord/test/models/publisher/article.rb
index d73a8eb936..355c22dcc5 100644
--- a/activerecord/test/models/publisher/article.rb
+++ b/activerecord/test/models/publisher/article.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Publisher::Article < ActiveRecord::Base
   has_and_belongs_to_many :magazines
   has_and_belongs_to_many :tags
diff --git a/activerecord/test/models/publisher/magazine.rb b/activerecord/test/models/publisher/magazine.rb
index 82e1a14008..425ede8df2 100644
--- a/activerecord/test/models/publisher/magazine.rb
+++ b/activerecord/test/models/publisher/magazine.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Publisher::Magazine < ActiveRecord::Base
   has_and_belongs_to_many :articles
 end
diff --git a/activerecord/test/models/randomly_named_c1.rb b/activerecord/test/models/randomly_named_c1.rb
index d4be1e13b4..f90a7b9336 100644
--- a/activerecord/test/models/randomly_named_c1.rb
+++ b/activerecord/test/models/randomly_named_c1.rb
@@ -1,3 +1,5 @@
-class ClassNameThatDoesNotFollowCONVENTIONS < ActiveRecord::Base

-  self.table_name = :randomly_named_table1

-end

+# frozen_string_literal: true
+
+class ClassNameThatDoesNotFollowCONVENTIONS < ActiveRecord::Base
+  self.table_name = :randomly_named_table1
+end
diff --git a/activerecord/test/models/rating.rb b/activerecord/test/models/rating.rb
index 25a52c4ad7..cf06bc6931 100644
--- a/activerecord/test/models/rating.rb
+++ b/activerecord/test/models/rating.rb
@@ -1,4 +1,6 @@
+# frozen_string_literal: true
+
 class Rating < ActiveRecord::Base
   belongs_to :comment
-  has_many :taggings, :as => :taggable
+  has_many :taggings, as: :taggable
 end
diff --git a/activerecord/test/models/reader.rb b/activerecord/test/models/reader.rb
index 91afc1898c..d25627e430 100644
--- a/activerecord/test/models/reader.rb
+++ b/activerecord/test/models/reader.rb
@@ -1,22 +1,24 @@
+# frozen_string_literal: true
+
 class Reader < ActiveRecord::Base
   belongs_to :post
-  belongs_to :person, :inverse_of => :readers
-  belongs_to :single_person, :class_name => 'Person', :foreign_key => :person_id, :inverse_of => :reader
+  belongs_to :person, inverse_of: :readers
+  belongs_to :single_person, class_name: "Person", foreign_key: :person_id, inverse_of: :reader
   belongs_to :first_post, -> { where(id: [2, 3]) }
 end
 
 class SecureReader < ActiveRecord::Base
   self.table_name = "readers"
 
-  belongs_to :secure_post, :class_name => "Post", :foreign_key => "post_id"
-  belongs_to :secure_person, :inverse_of => :secure_readers, :class_name => "Person", :foreign_key => "person_id"
+  belongs_to :secure_post, class_name: "Post", foreign_key: "post_id"
+  belongs_to :secure_person, inverse_of: :secure_readers, class_name: "Person", foreign_key: "person_id"
 end
 
 class LazyReader < ActiveRecord::Base
   self.table_name = "readers"
   default_scope -> { where(skimmer: true) }
 
-  scope :skimmers_or_not, -> { unscope(:where => :skimmer) }
+  scope :skimmers_or_not, -> { unscope(where: :skimmer) }
 
   belongs_to :post
   belongs_to :person
diff --git a/activerecord/test/models/recipe.rb b/activerecord/test/models/recipe.rb
index c387230603..e53f5c8fb1 100644
--- a/activerecord/test/models/recipe.rb
+++ b/activerecord/test/models/recipe.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Recipe < ActiveRecord::Base
   belongs_to :chef
 end
diff --git a/activerecord/test/models/record.rb b/activerecord/test/models/record.rb
index f77ac9fc03..63143e296a 100644
--- a/activerecord/test/models/record.rb
+++ b/activerecord/test/models/record.rb
@@ -1,2 +1,4 @@
+# frozen_string_literal: true
+
 class Record < ActiveRecord::Base
 end
diff --git a/activerecord/test/models/reference.rb b/activerecord/test/models/reference.rb
index c2f9068f57..2a7a1e3b77 100644
--- a/activerecord/test/models/reference.rb
+++ b/activerecord/test/models/reference.rb
@@ -1,8 +1,10 @@
+# frozen_string_literal: true
+
 class Reference < ActiveRecord::Base
   belongs_to :person
   belongs_to :job
 
-  has_many :agents_posts_authors, :through => :person
+  has_many :agents_posts_authors, through: :person
 
   class << self; attr_accessor :make_comments; end
   self.make_comments = false
@@ -17,6 +19,6 @@ class Reference < ActiveRecord::Base
 end
 
 class BadReference < ActiveRecord::Base
-  self.table_name = 'references'
-  default_scope { where(:favourite => false) }
+  self.table_name = "references"
+  default_scope { where(favourite: false) }
 end
diff --git a/activerecord/test/models/reply.rb b/activerecord/test/models/reply.rb
index 3e82e55d89..bc829ec67f 100644
--- a/activerecord/test/models/reply.rb
+++ b/activerecord/test/models/reply.rb
@@ -1,14 +1,16 @@
-require 'models/topic'
+# frozen_string_literal: true
+
+require "models/topic"
 
 class Reply < Topic
-  belongs_to :topic, :foreign_key => "parent_id", :counter_cache => true
-  belongs_to :topic_with_primary_key, :class_name => "Topic", :primary_key => "title", :foreign_key => "parent_title", :counter_cache => "replies_count"
-  has_many :replies, :class_name => "SillyReply", :dependent => :destroy, :foreign_key => "parent_id"
+  belongs_to :topic, foreign_key: "parent_id", counter_cache: true
+  belongs_to :topic_with_primary_key, class_name: "Topic", primary_key: "title", foreign_key: "parent_title", counter_cache: "replies_count"
+  has_many :replies, class_name: "SillyReply", dependent: :destroy, foreign_key: "parent_id"
 end
 
 class UniqueReply < Reply
-  belongs_to :topic, :foreign_key => 'parent_id', :counter_cache => true
-  validates_uniqueness_of :content, :scope => 'parent_id'
+  belongs_to :topic, foreign_key: "parent_id", counter_cache: true
+  validates_uniqueness_of :content, scope: "parent_id"
 end
 
 class SillyUniqueReply < UniqueReply
@@ -16,12 +18,12 @@ end
 
 class WrongReply < Reply
   validate :errors_on_empty_content
-  validate :title_is_wrong_create, :on => :create
+  validate :title_is_wrong_create, on: :create
 
   validate :check_empty_title
-  validate :check_content_mismatch, :on => :create
-  validate :check_wrong_update, :on => :update
-  validate :check_author_name_is_secret, :on => :special_case
+  validate :check_content_mismatch, on: :create
+  validate :check_wrong_update, on: :update
+  validate :check_author_name_is_secret, on: :special_case
 
   def check_empty_title
     errors[:title] << "Empty" unless attribute_present?("title")
@@ -51,11 +53,11 @@ class WrongReply < Reply
 end
 
 class SillyReply < Reply
-  belongs_to :reply, :foreign_key => "parent_id", :counter_cache => :replies_count
+  belongs_to :reply, foreign_key: "parent_id", counter_cache: :replies_count
 end
 
 module Web
   class Reply < Web::Topic
-    belongs_to :topic, :foreign_key => "parent_id", :counter_cache => true, :class_name => 'Web::Topic'
+    belongs_to :topic, foreign_key: "parent_id", counter_cache: true, class_name: "Web::Topic"
   end
 end
diff --git a/activerecord/test/models/ship.rb b/activerecord/test/models/ship.rb
index e333b964ab..7973219a79 100644
--- a/activerecord/test/models/ship.rb
+++ b/activerecord/test/models/ship.rb
@@ -1,20 +1,22 @@
+# frozen_string_literal: true
+
 class Ship < ActiveRecord::Base
   self.record_timestamps = false
 
   belongs_to :pirate
-  belongs_to :update_only_pirate, :class_name => 'Pirate'
+  belongs_to :update_only_pirate, class_name: "Pirate"
   belongs_to :developer, dependent: :destroy
-  has_many :parts, :class_name => 'ShipPart'
+  has_many :parts, class_name: "ShipPart"
   has_many :treasures
 
-  accepts_nested_attributes_for :parts, :allow_destroy => true
-  accepts_nested_attributes_for :pirate, :allow_destroy => true, :reject_if => proc(&:empty?)
-  accepts_nested_attributes_for :update_only_pirate, :update_only => true
+  accepts_nested_attributes_for :parts, allow_destroy: true
+  accepts_nested_attributes_for :pirate, allow_destroy: true, reject_if: proc(&:empty?)
+  accepts_nested_attributes_for :update_only_pirate, update_only: true
 
   validates_presence_of :name
 
   attr_accessor :cancel_save_from_callback
-  before_save :cancel_save_callback_method, :if => :cancel_save_from_callback
+  before_save :cancel_save_callback_method, if: :cancel_save_from_callback
   def cancel_save_callback_method
     throw(:abort)
   end
@@ -33,7 +35,7 @@ class Prisoner < ActiveRecord::Base
 end
 
 class FamousShip < ActiveRecord::Base
-  self.table_name = 'ships'
+  self.table_name = "ships"
   belongs_to :famous_pirate
   validates_presence_of :name, on: :conference
 end
diff --git a/activerecord/test/models/ship_part.rb b/activerecord/test/models/ship_part.rb
index 05c65f8a4a..f6d7a8ae5e 100644
--- a/activerecord/test/models/ship_part.rb
+++ b/activerecord/test/models/ship_part.rb
@@ -1,7 +1,9 @@
+# frozen_string_literal: true
+
 class ShipPart < ActiveRecord::Base
   belongs_to :ship
-  has_many :trinkets, :class_name => "Treasure", :as => :looter
-  accepts_nested_attributes_for :trinkets, :allow_destroy => true
+  has_many :trinkets, class_name: "Treasure", as: :looter
+  accepts_nested_attributes_for :trinkets, allow_destroy: true
   accepts_nested_attributes_for :ship
 
   validates_presence_of :name
diff --git a/activerecord/test/models/shop.rb b/activerecord/test/models/shop.rb
index 607a0a5b41..92afe70b92 100644
--- a/activerecord/test/models/shop.rb
+++ b/activerecord/test/models/shop.rb
@@ -1,10 +1,12 @@
+# frozen_string_literal: true
+
 module Shop
   class Collection < ActiveRecord::Base
-    has_many :products, :dependent => :nullify
+    has_many :products, dependent: :nullify
   end
 
   class Product < ActiveRecord::Base
-    has_many :variants, :dependent => :delete_all
+    has_many :variants, dependent: :delete_all
     belongs_to :type
 
     class Type < ActiveRecord::Base
diff --git a/activerecord/test/models/shop_account.rb b/activerecord/test/models/shop_account.rb
index 1580e8b20c..97fb058331 100644
--- a/activerecord/test/models/shop_account.rb
+++ b/activerecord/test/models/shop_account.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class ShopAccount < ActiveRecord::Base
   belongs_to :customer
   belongs_to :customer_carrier
diff --git a/activerecord/test/models/speedometer.rb b/activerecord/test/models/speedometer.rb
index 497c3aba9a..e456907a22 100644
--- a/activerecord/test/models/speedometer.rb
+++ b/activerecord/test/models/speedometer.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Speedometer < ActiveRecord::Base
   self.primary_key = :speedometer_id
   belongs_to :dashboard
diff --git a/activerecord/test/models/sponsor.rb b/activerecord/test/models/sponsor.rb
index ec3dcf8a97..f190860fd1 100644
--- a/activerecord/test/models/sponsor.rb
+++ b/activerecord/test/models/sponsor.rb
@@ -1,7 +1,9 @@
+# frozen_string_literal: true
+
 class Sponsor < ActiveRecord::Base
-  belongs_to :sponsor_club, :class_name => "Club", :foreign_key => "club_id"
-  belongs_to :sponsorable, :polymorphic => true
-  belongs_to :thing, :polymorphic => true, :foreign_type => :sponsorable_type, :foreign_key => :sponsorable_id
-  belongs_to :sponsorable_with_conditions, -> { where :name => 'Ernie'}, :polymorphic => true,
-             :foreign_type => 'sponsorable_type', :foreign_key => 'sponsorable_id'
+  belongs_to :sponsor_club, class_name: "Club", foreign_key: "club_id"
+  belongs_to :sponsorable, polymorphic: true
+  belongs_to :thing, polymorphic: true, foreign_type: :sponsorable_type, foreign_key: :sponsorable_id
+  belongs_to :sponsorable_with_conditions, -> { where name: "Ernie" }, polymorphic: true,
+             foreign_type: "sponsorable_type", foreign_key: "sponsorable_id"
 end
diff --git a/activerecord/test/models/string_key_object.rb b/activerecord/test/models/string_key_object.rb
index f084ec1bdc..473c145f4c 100644
--- a/activerecord/test/models/string_key_object.rb
+++ b/activerecord/test/models/string_key_object.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class StringKeyObject < ActiveRecord::Base
   self.primary_key = :id
 end
diff --git a/activerecord/test/models/student.rb b/activerecord/test/models/student.rb
index 28a0b6c99b..e750798f74 100644
--- a/activerecord/test/models/student.rb
+++ b/activerecord/test/models/student.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Student < ActiveRecord::Base
   has_and_belongs_to_many :lessons
   belongs_to :college
diff --git a/activerecord/test/models/subject.rb b/activerecord/test/models/subject.rb
deleted file mode 100644
index 8e28f8b86b..0000000000
--- a/activerecord/test/models/subject.rb
+++ /dev/null
@@ -1,16 +0,0 @@
-# used for OracleSynonymTest, see test/synonym_test_oracle.rb
-#
-class Subject < ActiveRecord::Base
-
-  # added initialization of author_email_address in the same way as in Topic class
-  # as otherwise synonym test was failing
-  after_initialize :set_email_address
-
-  protected
-    def set_email_address
-      unless self.persisted?
-        self.author_email_address = 'test@test.com'
-      end
-    end
-
-end
diff --git a/activerecord/test/models/subscriber.rb b/activerecord/test/models/subscriber.rb
index 76e85a0cd3..b21969ca2d 100644
--- a/activerecord/test/models/subscriber.rb
+++ b/activerecord/test/models/subscriber.rb
@@ -1,7 +1,9 @@
+# frozen_string_literal: true
+
 class Subscriber < ActiveRecord::Base
-  self.primary_key = 'nick'
+  self.primary_key = "nick"
   has_many :subscriptions
-  has_many :books, :through => :subscriptions
+  has_many :books, through: :subscriptions
 end
 
 class SpecialSubscriber < Subscriber
diff --git a/activerecord/test/models/subscription.rb b/activerecord/test/models/subscription.rb
index bcac4738a3..d1d5d21621 100644
--- a/activerecord/test/models/subscription.rb
+++ b/activerecord/test/models/subscription.rb
@@ -1,4 +1,6 @@
+# frozen_string_literal: true
+
 class Subscription < ActiveRecord::Base
-  belongs_to :subscriber, :counter_cache => :books_count
+  belongs_to :subscriber, counter_cache: :books_count
   belongs_to :book
 end
diff --git a/activerecord/test/models/tag.rb b/activerecord/test/models/tag.rb
index b48b9a2155..bc13c3a42d 100644
--- a/activerecord/test/models/tag.rb
+++ b/activerecord/test/models/tag.rb
@@ -1,13 +1,16 @@
+# frozen_string_literal: true
+
 class Tag < ActiveRecord::Base
   has_many :taggings
-  has_many :taggables, :through => :taggings
+  has_many :taggables, through: :taggings
   has_one  :tagging
 
-  has_many :tagged_posts, :through => :taggings, :source => 'taggable', :source_type => 'Post'
+  has_many :tagged_posts, through: :taggings, source: "taggable", source_type: "Post"
 end
 
 class OrderedTag < Tag
   self.table_name = "tags"
 
-  has_many :taggings, -> { order('taggings.id DESC') }, foreign_key: 'tag_id'
+  has_many :taggings, -> { order("taggings.id DESC") }, foreign_key: "tag_id"
+  has_many :tagged_posts, through: :taggings, source: "taggable", source_type: "Post"
 end
diff --git a/activerecord/test/models/tagging.rb b/activerecord/test/models/tagging.rb
index a6c05da26a..861fde633f 100644
--- a/activerecord/test/models/tagging.rb
+++ b/activerecord/test/models/tagging.rb
@@ -1,13 +1,16 @@
+# frozen_string_literal: true
+
 # test that attr_readonly isn't called on the :taggable polymorphic association
 module Taggable
 end
 
 class Tagging < ActiveRecord::Base
   belongs_to :tag, -> { includes(:tagging) }
-  belongs_to :super_tag,   :class_name => 'Tag', :foreign_key => 'super_tag_id'
-  belongs_to :invalid_tag, :class_name => 'Tag', :foreign_key => 'tag_id'
-  belongs_to :blue_tag, -> { where :tags => { :name => 'Blue' } }, :class_name => 'Tag', :foreign_key => :tag_id
-  belongs_to :tag_with_primary_key, :class_name => 'Tag', :foreign_key => :tag_id, :primary_key => :custom_primary_key
-  belongs_to :taggable, :polymorphic => true, :counter_cache => :tags_count
-  has_many :things, :through => :taggable
+  belongs_to :super_tag,   class_name: "Tag", foreign_key: "super_tag_id"
+  belongs_to :invalid_tag, class_name: "Tag", foreign_key: "tag_id"
+  belongs_to :ordered_tag, class_name: "OrderedTag", foreign_key: "tag_id"
+  belongs_to :blue_tag, -> { where tags: { name: "Blue" } }, class_name: "Tag", foreign_key: :tag_id
+  belongs_to :tag_with_primary_key, class_name: "Tag", foreign_key: :tag_id, primary_key: :custom_primary_key
+  belongs_to :taggable, polymorphic: true, counter_cache: :tags_count
+  has_many :things, through: :taggable
 end
diff --git a/activerecord/test/models/task.rb b/activerecord/test/models/task.rb
index e36989dd56..dabe3ce06b 100644
--- a/activerecord/test/models/task.rb
+++ b/activerecord/test/models/task.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Task < ActiveRecord::Base
   def updated_at
     ending
diff --git a/activerecord/test/models/topic.rb b/activerecord/test/models/topic.rb
index 176bc79dc7..8cd4dc352a 100644
--- a/activerecord/test/models/topic.rb
+++ b/activerecord/test/models/topic.rb
@@ -1,20 +1,22 @@
+# frozen_string_literal: true
+
 class Topic < ActiveRecord::Base
   scope :base, -> { all }
   scope :written_before, lambda { |time|
     if time
-      where 'written_on < ?', time
+      where "written_on < ?", time
     end
   }
-  scope :approved, -> { where(:approved => true) }
-  scope :rejected, -> { where(:approved => false) }
+  scope :approved, -> { where(approved: true) }
+  scope :rejected, -> { where(approved: false) }
 
   scope :scope_with_lambda, lambda { all }
 
-  scope :by_lifo, -> { where(:author_name => 'lifo') }
-  scope :replied, -> { where 'replies_count > 0' }
+  scope :by_lifo, -> { where(author_name: "lifo") }
+  scope :replied, -> { where "replies_count > 0" }
 
-  scope 'approved_as_string', -> { where(:approved => true) }
-  scope :anonymous_extension, -> { all } do
+  scope "approved_as_string", -> { where(approved: true) }
+  scope :anonymous_extension, -> {} do
     def one
       1
     end
@@ -22,7 +24,7 @@ class Topic < ActiveRecord::Base
 
   scope :with_object, Class.new(Struct.new(:klass)) {
     def call
-      klass.where(:approved => true)
+      klass.where(approved: true)
     end
   }.new(self)
 
@@ -33,22 +35,16 @@ class Topic < ActiveRecord::Base
   end
 
   has_many :replies, dependent: :destroy, foreign_key: "parent_id", autosave: true
-  has_many :approved_replies, -> { approved }, class_name: 'Reply', foreign_key: "parent_id", counter_cache: 'replies_count'
+  has_many :approved_replies, -> { approved }, class_name: "Reply", foreign_key: "parent_id", counter_cache: "replies_count"
 
-  has_many :unique_replies, :dependent => :destroy, :foreign_key => "parent_id"
-  has_many :silly_unique_replies, :dependent => :destroy, :foreign_key => "parent_id"
+  has_many :unique_replies, dependent: :destroy, foreign_key: "parent_id"
+  has_many :silly_unique_replies, dependent: :destroy, foreign_key: "parent_id"
 
   serialize :content
 
   before_create  :default_written_on
   before_destroy :destroy_children
 
-  # Explicitly define as :date column so that returned Oracle DATE values would be typecasted to Date and not Time.
-  # Some tests depend on assumption that this attribute will have Date values.
-  if current_adapter?(:OracleEnhancedAdapter)
-    set_date_columns :last_read
-  end
-
   def parent
     Topic.find(parent_id)
   end
@@ -69,6 +65,9 @@ class Topic < ActiveRecord::Base
 
   after_initialize :set_email_address
 
+  attr_accessor :change_approved_before_save
+  before_save :change_approved_callback
+
   class_attribute :after_initialize_called
   after_initialize do
     self.class.after_initialize_called = true
@@ -79,7 +78,7 @@ class Topic < ActiveRecord::Base
     write_attribute(:approved, val)
   end
 
-  protected
+  private
 
     def default_written_on
       self.written_on = Time.now unless attribute_present?("written_on")
@@ -90,8 +89,8 @@ class Topic < ActiveRecord::Base
     end
 
     def set_email_address
-      unless self.persisted?
-        self.author_email_address = 'test@test.com'
+      unless persisted?
+        self.author_email_address = "test@test.com"
       end
     end
 
@@ -100,6 +99,10 @@ class Topic < ActiveRecord::Base
     def before_destroy_for_transaction; end
     def after_save_for_transaction; end
     def after_create_for_transaction; end
+
+    def change_approved_callback
+      self.approved = change_approved_before_save unless change_approved_before_save.nil?
+    end
 end
 
 class ImportantTopic < Topic
@@ -119,6 +122,6 @@ end
 
 module Web
   class Topic < ActiveRecord::Base
-    has_many :replies, :dependent => :destroy, :foreign_key => "parent_id", :class_name => 'Web::Reply'
+    has_many :replies, dependent: :destroy, foreign_key: "parent_id", class_name: "Web::Reply"
   end
 end
diff --git a/activerecord/test/models/toy.rb b/activerecord/test/models/toy.rb
index ddc7048a56..4a5697eeb1 100644
--- a/activerecord/test/models/toy.rb
+++ b/activerecord/test/models/toy.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Toy < ActiveRecord::Base
   self.primary_key = :toy_id
   belongs_to :pet
diff --git a/activerecord/test/models/traffic_light.rb b/activerecord/test/models/traffic_light.rb
index a6b7edb882..0b88815cbd 100644
--- a/activerecord/test/models/traffic_light.rb
+++ b/activerecord/test/models/traffic_light.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class TrafficLight < ActiveRecord::Base
   serialize :state, Array
   serialize :long_state, Array
diff --git a/activerecord/test/models/treasure.rb b/activerecord/test/models/treasure.rb
index 63ff0c23ec..b51db56c37 100644
--- a/activerecord/test/models/treasure.rb
+++ b/activerecord/test/models/treasure.rb
@@ -1,11 +1,13 @@
+# frozen_string_literal: true
+
 class Treasure < ActiveRecord::Base
   has_and_belongs_to_many :parrots
-  belongs_to :looter, :polymorphic => true
+  belongs_to :looter, polymorphic: true
   # No counter_cache option given
   belongs_to :ship
 
-  has_many :price_estimates, :as => :estimate_of
-  has_and_belongs_to_many :rich_people, join_table: 'peoples_treasures', validate: false
+  has_many :price_estimates, as: :estimate_of
+  has_and_belongs_to_many :rich_people, join_table: "peoples_treasures", validate: false
 
   accepts_nested_attributes_for :looter
 end
diff --git a/activerecord/test/models/treaty.rb b/activerecord/test/models/treaty.rb
index 41fd1350f3..5c1d75aa09 100644
--- a/activerecord/test/models/treaty.rb
+++ b/activerecord/test/models/treaty.rb
@@ -1,7 +1,7 @@
-class Treaty < ActiveRecord::Base
+# frozen_string_literal: true
 
+class Treaty < ActiveRecord::Base
   self.primary_key = :treaty_id
 
   has_and_belongs_to_many :countries
-
 end
diff --git a/activerecord/test/models/tree.rb b/activerecord/test/models/tree.rb
index dc29cccc9c..77050c5fff 100644
--- a/activerecord/test/models/tree.rb
+++ b/activerecord/test/models/tree.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Tree < ActiveRecord::Base
   has_many :nodes, dependent: :destroy
 end
diff --git a/activerecord/test/models/tuning_peg.rb b/activerecord/test/models/tuning_peg.rb
index 1252d6dc1d..6e052e1d0f 100644
--- a/activerecord/test/models/tuning_peg.rb
+++ b/activerecord/test/models/tuning_peg.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class TuningPeg < ActiveRecord::Base
   belongs_to :guitar
   validates_numericality_of :pitch
diff --git a/activerecord/test/models/tyre.rb b/activerecord/test/models/tyre.rb
index e50a21ca68..d627026585 100644
--- a/activerecord/test/models/tyre.rb
+++ b/activerecord/test/models/tyre.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Tyre < ActiveRecord::Base
   belongs_to :car
 
diff --git a/activerecord/test/models/user.rb b/activerecord/test/models/user.rb
index f5dc93e994..3efbc45d2a 100644
--- a/activerecord/test/models/user.rb
+++ b/activerecord/test/models/user.rb
@@ -1,6 +1,18 @@
+# frozen_string_literal: true
+
+require "models/job"
+
 class User < ActiveRecord::Base
   has_secure_token
   has_secure_token :auth_token
+
+  has_and_belongs_to_many :jobs_pool,
+    class_name: "Job",
+    join_table: "jobs_pool"
+
+  has_one :family_tree, -> { where(token: nil) }, foreign_key: "member_id"
+  has_one :family, through: :family_tree
+  has_many :family_members, through: :family, source: :members
 end
 
 class UserWithNotification < User
diff --git a/activerecord/test/models/uuid_child.rb b/activerecord/test/models/uuid_child.rb
index a3d0962ad6..9fce361cc8 100644
--- a/activerecord/test/models/uuid_child.rb
+++ b/activerecord/test/models/uuid_child.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class UuidChild < ActiveRecord::Base
   belongs_to :uuid_parent
 end
diff --git a/activerecord/test/models/uuid_item.rb b/activerecord/test/models/uuid_item.rb
index 2353e40213..41f68c4c18 100644
--- a/activerecord/test/models/uuid_item.rb
+++ b/activerecord/test/models/uuid_item.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class UuidItem < ActiveRecord::Base
 end
 
diff --git a/activerecord/test/models/uuid_parent.rb b/activerecord/test/models/uuid_parent.rb
index 5634f22d0c..05db61855e 100644
--- a/activerecord/test/models/uuid_parent.rb
+++ b/activerecord/test/models/uuid_parent.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class UuidParent < ActiveRecord::Base
   has_many :uuid_children
 end
diff --git a/activerecord/test/models/vegetables.rb b/activerecord/test/models/vegetables.rb
index 1f41cde3a5..cfaab08ed1 100644
--- a/activerecord/test/models/vegetables.rb
+++ b/activerecord/test/models/vegetables.rb
@@ -1,9 +1,10 @@
-class Vegetable < ActiveRecord::Base
+# frozen_string_literal: true
 
+class Vegetable < ActiveRecord::Base
   validates_presence_of :name
 
   def self.inheritance_column
-    'custom_type'
+    "custom_type"
   end
 end
 
@@ -20,5 +21,5 @@ class KingCole < GreenCabbage
 end
 
 class RedCabbage < Cabbage
-  belongs_to :seller, :class_name => 'Company'
+  belongs_to :seller, class_name: "Company"
 end
diff --git a/activerecord/test/models/vehicle.rb b/activerecord/test/models/vehicle.rb
index ef26170f1f..c9b3338522 100644
--- a/activerecord/test/models/vehicle.rb
+++ b/activerecord/test/models/vehicle.rb
@@ -1,7 +1,9 @@
+# frozen_string_literal: true
+
 class Vehicle < ActiveRecord::Base
   self.abstract_class = true
   default_scope -> { where("tires_count IS NOT NULL") }
 end
 
 class Bus < Vehicle
-end
\ No newline at end of file
+end
diff --git a/activerecord/test/models/vertex.rb b/activerecord/test/models/vertex.rb
index 48bb851e62..0ad8114898 100644
--- a/activerecord/test/models/vertex.rb
+++ b/activerecord/test/models/vertex.rb
@@ -1,9 +1,11 @@
+# frozen_string_literal: true
+
 # This class models a vertex in a directed graph.
 class Vertex < ActiveRecord::Base
-  has_many :sink_edges, :class_name => 'Edge', :foreign_key => 'source_id'
-  has_many :sinks, :through => :sink_edges
+  has_many :sink_edges, class_name: "Edge", foreign_key: "source_id"
+  has_many :sinks, through: :sink_edges
 
   has_and_belongs_to_many :sources,
-    :class_name => 'Vertex', :join_table => 'edges',
-    :foreign_key => 'sink_id', :association_foreign_key => 'source_id'
+    class_name: "Vertex", join_table: "edges",
+    foreign_key: "sink_id", association_foreign_key: "source_id"
 end
diff --git a/activerecord/test/models/warehouse_thing.rb b/activerecord/test/models/warehouse_thing.rb
index f20bd1a245..099633af55 100644
--- a/activerecord/test/models/warehouse_thing.rb
+++ b/activerecord/test/models/warehouse_thing.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class WarehouseThing < ActiveRecord::Base
   self.table_name = "warehouse-things"
 
diff --git a/activerecord/test/models/wheel.rb b/activerecord/test/models/wheel.rb
index 26868bce5e..8db57d181e 100644
--- a/activerecord/test/models/wheel.rb
+++ b/activerecord/test/models/wheel.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Wheel < ActiveRecord::Base
-  belongs_to :wheelable, :polymorphic => true, :counter_cache => true
+  belongs_to :wheelable, polymorphic: true, counter_cache: true, touch: true
 end
diff --git a/activerecord/test/models/without_table.rb b/activerecord/test/models/without_table.rb
index 50c824e4ac..fc0a52d6ad 100644
--- a/activerecord/test/models/without_table.rb
+++ b/activerecord/test/models/without_table.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class WithoutTable < ActiveRecord::Base
-  default_scope -> { where(:published => true) }
+  default_scope -> { where(published: true) }
 end
diff --git a/activerecord/test/models/zine.rb b/activerecord/test/models/zine.rb
index c2d0fdaf25..6f361665ef 100644
--- a/activerecord/test/models/zine.rb
+++ b/activerecord/test/models/zine.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Zine < ActiveRecord::Base
-  has_many :interests, :inverse_of => :zine
+  has_many :interests, inverse_of: :zine
 end
diff --git a/activerecord/test/schema/mysql2_specific_schema.rb b/activerecord/test/schema/mysql2_specific_schema.rb
index 5a49b38457..e634e9e6b1 100644
--- a/activerecord/test/schema/mysql2_specific_schema.rb
+++ b/activerecord/test/schema/mysql2_specific_schema.rb
@@ -1,11 +1,18 @@
+# frozen_string_literal: true
+
 ActiveRecord::Schema.define do
 
-  if ActiveRecord::Base.connection.version >= '5.6.0'
+  if ActiveRecord::Base.connection.version >= "5.6.0"
     create_table :datetime_defaults, force: true do |t|
-      t.datetime :modified_datetime, default: -> { 'CURRENT_TIMESTAMP' }
+      t.datetime :modified_datetime, default: -> { "CURRENT_TIMESTAMP" }
     end
   end
 
+  create_table :timestamp_defaults, force: true do |t|
+    t.timestamp :nullable_timestamp
+    t.timestamp :modified_timestamp, default: -> { "CURRENT_TIMESTAMP" }
+  end
+
   create_table :binary_fields, force: true do |t|
     t.binary :var_binary, limit: 255
     t.binary :var_binary_large, limit: 4095
@@ -21,18 +28,18 @@ ActiveRecord::Schema.define do
     t.index :var_binary
   end
 
-  create_table :key_tests, force: true, options: 'ENGINE=MyISAM' do |t|
+  create_table :key_tests, force: true, options: "ENGINE=MyISAM" do |t|
     t.string :awesome
     t.string :pizza
     t.string :snacks
-    t.index :awesome, type: :fulltext, name: 'index_key_tests_on_awesome'
-    t.index :pizza, using: :btree, name: 'index_key_tests_on_pizza'
-    t.index :snacks, name: 'index_key_tests_on_snack'
+    t.index :awesome, type: :fulltext, name: "index_key_tests_on_awesome"
+    t.index :pizza, using: :btree, name: "index_key_tests_on_pizza"
+    t.index :snacks, name: "index_key_tests_on_snack"
   end
 
   create_table :collation_tests, id: false, force: true do |t|
-    t.string :string_cs_column, limit: 1, collation: 'utf8_bin'
-    t.string :string_ci_column, limit: 1, collation: 'utf8_general_ci'
+    t.string :string_cs_column, limit: 1, collation: "utf8_bin"
+    t.string :string_ci_column, limit: 1, collation: "utf8_general_ci"
     t.binary :binary_column,    limit: 1
   end
 
diff --git a/activerecord/test/schema/oracle_specific_schema.rb b/activerecord/test/schema/oracle_specific_schema.rb
index 264d9b8910..e236571caa 100644
--- a/activerecord/test/schema/oracle_specific_schema.rb
+++ b/activerecord/test/schema/oracle_specific_schema.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 ActiveRecord::Schema.define do
 
   execute "drop table test_oracle_defaults" rescue nil
diff --git a/activerecord/test/schema/postgresql_specific_schema.rb b/activerecord/test/schema/postgresql_specific_schema.rb
index 24713f722a..f15178d695 100644
--- a/activerecord/test/schema/postgresql_specific_schema.rb
+++ b/activerecord/test/schema/postgresql_specific_schema.rb
@@ -1,64 +1,62 @@
+# frozen_string_literal: true
+
 ActiveRecord::Schema.define do
 
-  enable_extension!('uuid-ossp', ActiveRecord::Base.connection)
+  enable_extension!("uuid-ossp", ActiveRecord::Base.connection)
+  enable_extension!("pgcrypto",  ActiveRecord::Base.connection) if ActiveRecord::Base.connection.supports_pgcrypto_uuid?
+
+  uuid_default = connection.supports_pgcrypto_uuid? ? {} : { default: "uuid_generate_v4()" }
 
-  create_table :uuid_parents, id: :uuid, force: true do |t|
+  create_table :uuid_parents, id: :uuid, force: true, **uuid_default do |t|
     t.string :name
   end
 
-  create_table :uuid_children, id: :uuid, force: true do |t|
+  create_table :uuid_children, id: :uuid, force: true, **uuid_default do |t|
     t.string :name
     t.uuid :uuid_parent_id
   end
 
   create_table :defaults, force: true do |t|
-    t.date :modified_date, default: -> { 'CURRENT_DATE' }
-    t.date :modified_date_function, default: -> { 'now()' }
-    t.date :fixed_date, default: '2004-01-01'
-    t.datetime :modified_time, default: -> { 'CURRENT_TIMESTAMP' }
-    t.datetime :modified_time_function, default: -> { 'now()' }
-    t.datetime :fixed_time, default: '2004-01-01 00:00:00.000000-00'
-    t.column :char1, 'char(1)', default: 'Y'
-    t.string :char2, limit: 50, default: 'a varchar field'
-    t.text :char3, default: 'a text field'
-    t.bigint :bigint_default, default: -> { '0::bigint' }
-    t.text :multiline_default, default: '--- []
-
-'
+    t.date :modified_date, default: -> { "CURRENT_DATE" }
+    t.date :modified_date_function, default: -> { "now()" }
+    t.date :fixed_date, default: "2004-01-01"
+    t.datetime :modified_time, default: -> { "CURRENT_TIMESTAMP" }
+    t.datetime :modified_time_function, default: -> { "now()" }
+    t.datetime :fixed_time, default: "2004-01-01 00:00:00.000000-00"
+    t.column :char1, "char(1)", default: "Y"
+    t.string :char2, limit: 50, default: "a varchar field"
+    t.text :char3, default: "a text field"
+    t.bigint :bigint_default, default: -> { "0::bigint" }
+    t.text :multiline_default, default: "--- []
+
+"
+  end
+
+  create_table :postgresql_times, force: true do |t|
+    t.interval :time_interval
+    t.interval :scaled_time_interval, precision: 6
   end
 
-  %w(postgresql_times postgresql_oids postgresql_timestamp_with_zones
-      postgresql_partitioned_table postgresql_partitioned_table_parent).each do |table_name|
-    drop_table table_name, if_exists: true
+  create_table :postgresql_oids, force: true do |t|
+    t.oid :obj_id
   end
 
-  execute 'DROP SEQUENCE IF EXISTS companies_nonstd_seq CASCADE'
-  execute 'CREATE SEQUENCE companies_nonstd_seq START 101 OWNED BY companies.id'
+  drop_table "postgresql_timestamp_with_zones", if_exists: true
+  drop_table "postgresql_partitioned_table", if_exists: true
+  drop_table "postgresql_partitioned_table_parent", if_exists: true
+
+  execute "DROP SEQUENCE IF EXISTS companies_nonstd_seq CASCADE"
+  execute "CREATE SEQUENCE companies_nonstd_seq START 101 OWNED BY companies.id"
   execute "ALTER TABLE companies ALTER COLUMN id SET DEFAULT nextval('companies_nonstd_seq')"
-  execute 'DROP SEQUENCE IF EXISTS companies_id_seq'
+  execute "DROP SEQUENCE IF EXISTS companies_id_seq"
 
-  execute 'DROP FUNCTION IF EXISTS partitioned_insert_trigger()'
+  execute "DROP FUNCTION IF EXISTS partitioned_insert_trigger()"
 
   %w(accounts_id_seq developers_id_seq projects_id_seq topics_id_seq customers_id_seq orders_id_seq).each do |seq_name|
     execute "SELECT setval('#{seq_name}', 100)"
   end
 
   execute <<_SQL
-  CREATE TABLE postgresql_times (
-    id SERIAL PRIMARY KEY,
-    time_interval INTERVAL,
-    scaled_time_interval INTERVAL(6)
-  );
-_SQL
-
-  execute <<_SQL
-  CREATE TABLE postgresql_oids (
-    id SERIAL PRIMARY KEY,
-    obj_id OID
-  );
-_SQL
-
-  execute <<_SQL
   CREATE TABLE postgresql_timestamp_with_zones (
     id SERIAL PRIMARY KEY,
     time TIMESTAMP WITH TIME ZONE
@@ -88,7 +86,7 @@ _SQL
       FOR EACH ROW EXECUTE PROCEDURE partitioned_insert_trigger();
 _SQL
   rescue ActiveRecord::StatementInvalid => e
-    if e.message =~ /language "plpgsql" does not exist/
+    if e.message.include?('language "plpgsql" does not exist')
       execute "CREATE LANGUAGE 'plpgsql';"
       retry
     else
@@ -108,7 +106,7 @@ _SQL
   end
 
   create_table :uuid_items, force: true, id: false do |t|
-    t.uuid :uuid, primary_key: true
+    t.uuid :uuid, primary_key: true, **uuid_default
     t.string :title
   end
 end
diff --git a/activerecord/test/schema/schema.rb b/activerecord/test/schema/schema.rb
index 628a59c2e3..3205c4c20a 100644
--- a/activerecord/test/schema/schema.rb
+++ b/activerecord/test/schema/schema.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 ActiveRecord::Schema.define do
   # ------------------------------------------------------------------- #
   #                                                                     #
@@ -7,7 +9,7 @@ ActiveRecord::Schema.define do
   # ------------------------------------------------------------------- #
 
   create_table :accounts, force: true do |t|
-    t.integer :firm_id
+    t.references :firm, index: false
     t.string  :firm_name
     t.integer :credit_limit
   end
@@ -21,7 +23,7 @@ ActiveRecord::Schema.define do
     t.string :settings, null: true, limit: 1024
     # MySQL does not allow default values for blobs. Fake it out with a
     # big varchar below.
-    t.string :preferences, null: true, default: '', limit: 1024
+    t.string :preferences, null: true, default: "", limit: 1024
     t.string :json_data, null: true, limit: 1024
     t.string :json_data_empty, null: true, default: "", limit: 1024
     t.text :params
@@ -54,8 +56,8 @@ ActiveRecord::Schema.define do
 
   create_table :authors, force: true do |t|
     t.string :name, null: false
-    t.integer :author_address_id
-    t.integer :author_address_extra_id
+    t.references :author_address
+    t.references :author_address_extra
     t.string :organization_id
     t.string :owned_essay_id
   end
@@ -88,7 +90,7 @@ ActiveRecord::Schema.define do
   end
 
   create_table :books, force: true do |t|
-    t.integer :author_id
+    t.references :author
     t.string :format
     t.column :name, :string
     t.column :status, :integer, default: 0
@@ -98,7 +100,8 @@ ActiveRecord::Schema.define do
     t.column :author_visibility, :integer, default: 0
     t.column :illustrator_visibility, :integer, default: 0
     t.column :font_size, :integer, default: 0
-    t.column :cover, :string, default: 'hard'
+    t.column :difficulty, :integer, default: 0
+    t.column :cover, :string, default: "hard"
   end
 
   create_table :booleans, force: true do |t|
@@ -106,7 +109,7 @@ ActiveRecord::Schema.define do
     t.boolean :has_fun, null: false, default: false
   end
 
-  create_table :bulbs, force: true do |t|
+  create_table :bulbs, primary_key: "ID", force: true do |t|
     t.integer :car_id
     t.string  :name
     t.boolean :frickinawesome, default: false
@@ -120,11 +123,14 @@ ActiveRecord::Schema.define do
   create_table :cars, force: true do |t|
     t.string  :name
     t.integer :engines_count
-    t.integer :wheels_count
+    t.integer :wheels_count, default: 0
     t.column :lock_version, :integer, null: false, default: 0
     t.timestamps null: false
   end
 
+  create_table :old_cars, id: :integer, force: true do |t|
+  end
+
   create_table :carriers, force: true
 
   create_table :categories, force: true do |t|
@@ -185,21 +191,26 @@ ActiveRecord::Schema.define do
     t.string :resource_id
     t.string :resource_type
     t.integer :developer_id
+    t.datetime :updated_at
+    t.datetime :deleted_at
+    t.integer :comments
   end
 
   create_table :companies, force: true do |t|
     t.string  :type
-    t.integer :firm_id
+    t.references :firm, index: false
     t.string  :firm_name
     t.string  :name
-    t.integer :client_of
-    t.integer :rating, default: 1
+    t.bigint :client_of
+    t.bigint :rating, default: 1
     t.integer :account_id
     t.string :description, default: ""
-    t.index [:firm_id, :type, :rating], name: "company_index"
-    t.index [:firm_id, :type], name: "company_partial_index", where: "rating > 10"
-    t.index :name, name: 'company_name_index', using: :btree
-    t.index 'lower(name)', name: "company_expression_index" if supports_expression_index?
+    t.index [:name, :rating], order: :desc
+    t.index [:name, :description], length: 10
+    t.index [:firm_id, :type, :rating], name: "company_index", length: { type: 10 }, order: { rating: :desc }
+    t.index [:firm_id, :type], name: "company_partial_index", where: "(rating > 10)"
+    t.index :name, name: "company_name_index", using: :btree
+    t.index "lower(name)", name: "company_expression_index" if supports_expression_index?
   end
 
   create_table :content, force: true do |t|
@@ -228,8 +239,8 @@ ActiveRecord::Schema.define do
   end
 
   create_table :contracts, force: true do |t|
-    t.integer :developer_id
-    t.integer :company_id
+    t.references :developer, index: false
+    t.references :company, index: false
   end
 
   create_table :customers, force: true do |t|
@@ -255,7 +266,7 @@ ActiveRecord::Schema.define do
     t.string   :name
     t.string   :first_name
     t.integer  :salary, default: 70000
-    t.integer :firm_id
+    t.references :firm, index: false
     t.integer :mentor_id
     if subsecond_precision_supported?
       t.datetime :created_at, precision: 6
@@ -298,11 +309,11 @@ ActiveRecord::Schema.define do
   create_table :edges, force: true, id: false do |t|
     t.column :source_id, :integer, null: false
     t.column :sink_id,   :integer, null: false
-    t.index [:source_id, :sink_id], unique: true, name: 'unique_edge_index'
+    t.index [:source_id, :sink_id], unique: true, name: "unique_edge_index"
   end
 
   create_table :engines, force: true do |t|
-    t.integer :car_id
+    t.references :car, index: false
   end
 
   create_table :entrants, force: true do |t|
@@ -325,6 +336,15 @@ ActiveRecord::Schema.define do
   create_table :eyes, force: true do |t|
   end
 
+  create_table :families, force: true do |t|
+  end
+
+  create_table :family_trees, force: true do |t|
+    t.references :family
+    t.references :member
+    t.string :token
+  end
+
   create_table :funny_jokes, force: true do |t|
     t.string :name
   end
@@ -390,11 +410,19 @@ ActiveRecord::Schema.define do
     t.integer :ideal_reference_id
   end
 
+  create_table :jobs_pool, force: true, id: false do |t|
+    t.references :job, null: false, index: true
+    t.references :user, null: false, index: true
+  end
+
   create_table :keyboards, force: true, id: false do |t|
     t.primary_key :key_number
     t.string      :name
   end
 
+  create_table :kitchens, force: true do |t|
+  end
+
   create_table :legacy_things, force: true do |t|
     t.integer :tps_report_number
     t.integer :version, null: false, default: 0
@@ -409,6 +437,14 @@ ActiveRecord::Schema.define do
     t.references :student
   end
 
+  create_table :students, force: true do |t|
+    t.string :name
+    t.boolean :active
+    t.integer :college_id
+  end
+
+  add_foreign_key :lessons_students, :students, on_delete: :cascade
+
   create_table :lint_models, force: true
 
   create_table :line_items, force: true do |t|
@@ -422,11 +458,15 @@ ActiveRecord::Schema.define do
   end
 
   create_table :lock_without_defaults, force: true do |t|
+    t.column :title, :string
     t.column :lock_version, :integer
+    t.timestamps null: true
   end
 
   create_table :lock_without_defaults_cust, force: true do |t|
+    t.column :title, :string
     t.column :custom_lock_version, :integer
+    t.timestamps null: true
   end
 
   create_table :magazines, force: true do |t|
@@ -458,7 +498,7 @@ ActiveRecord::Schema.define do
     t.datetime :joined_on
     t.integer :club_id, :member_id
     t.boolean :favourite, default: false
-    t.string :type
+    t.integer :type
   end
 
   create_table :member_types, force: true do |t|
@@ -555,6 +595,7 @@ ActiveRecord::Schema.define do
     t.column :color, :string
     t.column :parrot_sti_class, :string
     t.column :killer_id, :integer
+    t.column :updated_count, :integer, default: 0
     if subsecond_precision_supported?
       t.column :created_at, :datetime, precision: 0
       t.column :created_on, :datetime, precision: 0
@@ -635,8 +676,8 @@ ActiveRecord::Schema.define do
   end
 
   create_table :posts, force: true do |t|
-    t.integer :author_id
-    t.string  :title, null: false
+    t.references :author
+    t.string :title, null: false
     # use VARCHAR2(4000) instead of CLOB datatype as CLOB data type has many limitations in
     # Oracle SELECT WHERE clause which causes many unit test failures
     if current_adapter?(:OracleAdapter)
@@ -682,7 +723,7 @@ ActiveRecord::Schema.define do
   create_table :projects, force: true do |t|
     t.string :name
     t.string :type
-    t.integer :firm_id
+    t.references :firm, index: false
     t.integer :mentor_id
   end
 
@@ -754,6 +795,10 @@ ActiveRecord::Schema.define do
     t.belongs_to :ship
   end
 
+  create_table :sinks, force: true do |t|
+    t.references :kitchen
+  end
+
   create_table :shop_accounts, force: true do |t|
     t.references :customer
     t.references :customer_carrier
@@ -767,26 +812,22 @@ ActiveRecord::Schema.define do
 
   create_table :sponsors, force: true do |t|
     t.integer :club_id
-    t.integer :sponsorable_id
-    t.string :sponsorable_type
-  end
-
-  create_table :string_key_objects, id: false, primary_key: :id, force: true do |t|
-    t.string     :id
-    t.string     :name
-    t.integer    :lock_version, null: false, default: 0
+    t.references :sponsorable, polymorphic: true, index: false
   end
 
-  create_table :students, force: true do |t|
+  create_table :string_key_objects, id: false, force: true do |t|
+    t.string :id, null: false
     t.string :name
-    t.boolean :active
-    t.integer :college_id
+    t.integer :lock_version, null: false, default: 0
+    t.index :id, unique: true
   end
 
-  create_table :subscribers, force: true, id: false do |t|
+  create_table :subscribers, id: false, force: true do |t|
     t.string :nick, null: false
     t.string :name
-    t.column :books_count, :integer, null: false, default: 0
+    t.integer :id
+    t.integer :books_count, null: false, default: 0
+    t.integer :update_count, null: false, default: 0
     t.index :nick, unique: true
   end
 
@@ -887,15 +928,14 @@ ActiveRecord::Schema.define do
     t.column :label, :string
   end
 
-  create_table 'warehouse-things', force: true do |t|
+  create_table "warehouse-things", force: true do |t|
     t.integer :value
   end
 
   [:circles, :squares, :triangles, :non_poly_ones, :non_poly_twos].each do |t|
-    create_table(t, force: true) { }
+    create_table(t, force: true) {}
   end
 
-  # NOTE - the following 4 tables are used by models that have :inverse_of options on the associations
   create_table :men, force: true do |t|
     t.string  :name
   end
@@ -919,19 +959,20 @@ ActiveRecord::Schema.define do
     t.integer :zine_id
   end
 
-  create_table :wheels, force: true do |t|
-    t.references :wheelable, polymorphic: true
-  end
-
   create_table :zines, force: true do |t|
     t.string :title
   end
 
-  create_table :countries, force: true, id: false, primary_key: 'country_id' do |t|
+  create_table :wheels, force: true do |t|
+    t.integer :size
+    t.references :wheelable, polymorphic: true
+  end
+
+  create_table :countries, force: true, id: false, primary_key: "country_id" do |t|
     t.string :country_id
     t.string :name
   end
-  create_table :treaties, force: true, id: false, primary_key: 'treaty_id' do |t|
+  create_table :treaties, force: true, id: false, primary_key: "treaty_id" do |t|
     t.string :treaty_id
     t.string :name
   end
@@ -952,9 +993,9 @@ ActiveRecord::Schema.define do
     t.string :name
   end
   create_table :weirds, force: true do |t|
-    t.string 'a$b'
-    t.string 'なまえ'
-    t.string 'from'
+    t.string "a$b"
+    t.string "なまえ"
+    t.string "from"
   end
 
   create_table :nodes, force: true do |t|
@@ -992,24 +1033,21 @@ ActiveRecord::Schema.define do
   create_table :records, force: true do |t|
   end
 
-  if supports_foreign_keys?
-    # fk_test_has_fk should be before fk_test_has_pk
-    create_table :fk_test_has_fk, force: true do |t|
-      t.integer :fk_id, null: false
+  disable_referential_integrity do
+    create_table :fk_test_has_pk, primary_key: "pk_id", force: :cascade do |t|
     end
 
-    create_table :fk_test_has_pk, force: true, primary_key: "pk_id" do |t|
+    create_table :fk_test_has_fk, force: true do |t|
+      t.references :fk, null: false
+      t.foreign_key :fk_test_has_pk, column: "fk_id", name: "fk_name", primary_key: "pk_id"
     end
-
-    add_foreign_key :fk_test_has_fk, :fk_test_has_pk, column: "fk_id", name: "fk_name", primary_key: "pk_id"
-    add_foreign_key :lessons_students, :students
   end
 
   create_table :overloaded_types, force: true do |t|
     t.float :overloaded_float, default: 500
     t.float :unoverloaded_float
     t.string :overloaded_string_with_limit, limit: 255
-    t.string :string_with_default, default: 'the original default'
+    t.string :string_with_default, default: "the original default"
   end
 
   create_table :users, force: true do |t|
@@ -1020,6 +1058,10 @@ ActiveRecord::Schema.define do
   create_table :test_with_keyword_column_name, force: true do |t|
     t.string :desc
   end
+
+  create_table :non_primary_keys, force: true, id: false do |t|
+    t.integer :id
+  end
 end
 
 Course.connection.create_table :courses, force: true do |t|
@@ -1039,3 +1081,5 @@ Professor.connection.create_table :courses_professors, id: false, force: true do
   t.references :course
   t.references :professor
 end
+
+OtherDog.connection.create_table :dogs, force: true
diff --git a/activerecord/test/schema/sqlite_specific_schema.rb b/activerecord/test/schema/sqlite_specific_schema.rb
deleted file mode 100644
index cc7c36fe2b..0000000000
--- a/activerecord/test/schema/sqlite_specific_schema.rb
+++ /dev/null
@@ -1,18 +0,0 @@
-ActiveRecord::Schema.define do
-  execute "DROP TABLE fk_test_has_fk" rescue nil
-  execute "DROP TABLE fk_test_has_pk" rescue nil
-  execute <<_SQL
-  CREATE TABLE 'fk_test_has_pk' (
-    'pk_id' INTEGER NOT NULL PRIMARY KEY
-  );
-_SQL
-
-  execute <<_SQL
-  CREATE TABLE 'fk_test_has_fk' (
-    'id'    INTEGER NOT NULL PRIMARY KEY,
-    'fk_id' INTEGER NOT NULL,
-
-    FOREIGN KEY ('fk_id') REFERENCES 'fk_test_has_pk'('pk_id')
-  );
-_SQL
-end
diff --git a/activerecord/test/support/config.rb b/activerecord/test/support/config.rb
index 6d123688a3..bd6d5c339b 100644
--- a/activerecord/test/support/config.rb
+++ b/activerecord/test/support/config.rb
@@ -1,7 +1,9 @@
-require 'yaml'
-require 'erubis'
-require 'fileutils'
-require 'pathname'
+# frozen_string_literal: true
+
+require "yaml"
+require "erb"
+require "fileutils"
+require "pathname"
 
 module ARTest
   class << self
@@ -12,28 +14,29 @@ module ARTest
     private
 
     def config_file
-      Pathname.new(ENV['ARCONFIG'] || TEST_ROOT + '/config.yml')
+      Pathname.new(ENV["ARCONFIG"] || TEST_ROOT + "/config.yml")
     end
 
     def read_config
       unless config_file.exist?
-        FileUtils.cp TEST_ROOT + '/config.example.yml', config_file
+        FileUtils.cp TEST_ROOT + "/config.example.yml", config_file
       end
 
-      erb = Erubis::Eruby.new(config_file.read)
+      erb = ERB.new(config_file.read)
       expand_config(YAML.parse(erb.result(binding)).transform)
     end
 
     def expand_config(config)
-      config['connections'].each do |adapter, connection|
-        dbs = [['arunit', 'activerecord_unittest'], ['arunit2', 'activerecord_unittest2']]
+      config["connections"].each do |adapter, connection|
+        dbs = [["arunit", "activerecord_unittest"], ["arunit2", "activerecord_unittest2"],
+               ["arunit_without_prepared_statements", "activerecord_unittest"]]
         dbs.each do |name, dbname|
           unless connection[name].is_a?(Hash)
-            connection[name] = { 'database' => connection[name] }
+            connection[name] = { "database" => connection[name] }
           end
 
-          connection[name]['database'] ||= dbname
-          connection[name]['adapter']  ||= adapter
+          connection[name]["database"] ||= dbname
+          connection[name]["adapter"]  ||= adapter
         end
       end
 
diff --git a/activerecord/test/support/connection.rb b/activerecord/test/support/connection.rb
index c5334e8596..2a4fa53460 100644
--- a/activerecord/test/support/connection.rb
+++ b/activerecord/test/support/connection.rb
@@ -1,15 +1,21 @@
-require 'active_support/logger'
-require 'models/college'
-require 'models/course'
-require 'models/professor'
+# frozen_string_literal: true
+
+require "active_support/logger"
+require "models/college"
+require "models/course"
+require "models/professor"
+require "models/other_dog"
 
 module ARTest
   def self.connection_name
-    ENV['ARCONN'] || config['default_connection']
+    ENV["ARCONN"] || config["default_connection"]
   end
 
   def self.connection_config
-    config['connections'][connection_name]
+    config.fetch("connections").fetch(connection_name) do
+      puts "Connection #{connection_name.inspect} not found. Available connections: #{config['connections'].keys.join(', ')}"
+      exit 1
+    end
   end
 
   def self.connect
diff --git a/activerecord/test/support/connection_helper.rb b/activerecord/test/support/connection_helper.rb
index 4a19e5df44..3bb1b370c1 100644
--- a/activerecord/test/support/connection_helper.rb
+++ b/activerecord/test/support/connection_helper.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ConnectionHelper
   def run_without_connection
     original_connection = ActiveRecord::Base.remove_connection
diff --git a/activerecord/test/support/ddl_helper.rb b/activerecord/test/support/ddl_helper.rb
index 43cb235e01..a18bf5ea0a 100644
--- a/activerecord/test/support/ddl_helper.rb
+++ b/activerecord/test/support/ddl_helper.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module DdlHelper
   def with_example_table(connection, table_name, definition = nil)
     connection.execute("CREATE TABLE #{table_name}(#{definition})")
diff --git a/activerecord/test/support/schema_dumping_helper.rb b/activerecord/test/support/schema_dumping_helper.rb
index 666c1b6a14..777e6a7c1b 100644
--- a/activerecord/test/support/schema_dumping_helper.rb
+++ b/activerecord/test/support/schema_dumping_helper.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module SchemaDumpingHelper
   def dump_table_schema(table, connection = ActiveRecord::Base.connection)
     old_ignore_tables = ActiveRecord::SchemaDumper.ignore_tables
diff --git a/activestorage/.babelrc b/activestorage/.babelrc
new file mode 100644
index 0000000000..a8211d329f
--- /dev/null
+++ b/activestorage/.babelrc
@@ -0,0 +1,5 @@
+{
+  "presets": [
+    ["env", { "modules": false } ]
+  ]
+}
diff --git a/activestorage/.eslintrc b/activestorage/.eslintrc
new file mode 100644
index 0000000000..3d9ecd4bce
--- /dev/null
+++ b/activestorage/.eslintrc
@@ -0,0 +1,19 @@
+{
+  "extends": "eslint:recommended",
+  "rules": {
+    "semi": ["error", "never"],
+    "quotes": ["error", "double"],
+    "no-unused-vars": ["error", { "vars": "all", "args": "none" }]
+  },
+  "plugins": [
+    "import"
+  ],
+  "env": {
+    "browser": true,
+    "es6": true
+  },
+  "parserOptions": {
+    "ecmaVersion": 6,
+    "sourceType": "module"
+  }
+}
diff --git a/activestorage/.gitignore b/activestorage/.gitignore
new file mode 100644
index 0000000000..a532335bdd
--- /dev/null
+++ b/activestorage/.gitignore
@@ -0,0 +1,6 @@
+.byebug_history
+node_modules
+test/dummy/db/*.sqlite3
+test/dummy/db/*.sqlite3-journal
+test/dummy/log/*.log
+test/dummy/tmp/
diff --git a/activestorage/CHANGELOG.md b/activestorage/CHANGELOG.md
new file mode 100644
index 0000000000..c5171e7490
--- /dev/null
+++ b/activestorage/CHANGELOG.md
@@ -0,0 +1,12 @@
+## Rails 5.2.0.beta2 (November 28, 2017) ##
+
+*   Fix the gem adding the migrations files to the package.
+
+    *Yuji Yaginuma*
+
+
+## Rails 5.2.0.beta1 (November 27, 2017) ##
+
+*   Added to Rails.
+
+    *DHH*
diff --git a/activestorage/MIT-LICENSE b/activestorage/MIT-LICENSE
new file mode 100644
index 0000000000..eed89ac398
--- /dev/null
+++ b/activestorage/MIT-LICENSE
@@ -0,0 +1,20 @@
+Copyright (c) 2017-2018 David Heinemeier Hansson, Basecamp
+
+Permission is hereby granted, free of charge, to any person obtaining
+a copy of this software and associated documentation files (the
+"Software"), to deal in the Software without restriction, including
+without limitation the rights to use, copy, modify, merge, publish,
+distribute, sublicense, and/or sell copies of the Software, and to
+permit persons to whom the Software is furnished to do so, subject to
+the following conditions:
+
+The above copyright notice and this permission notice shall be
+included in all copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
+LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
+OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
diff --git a/activestorage/README.md b/activestorage/README.md
new file mode 100644
index 0000000000..85ab70dac6
--- /dev/null
+++ b/activestorage/README.md
@@ -0,0 +1,159 @@
+# Active Storage
+
+Active Storage makes it simple to upload and reference files in cloud services like [Amazon S3](https://aws.amazon.com/s3/), [Google Cloud Storage](https://cloud.google.com/storage/docs/), or [Microsoft Azure Storage](https://azure.microsoft.com/en-us/services/storage/), and attach those files to Active Records. Supports having one main service and mirrors in other services for redundancy. It also provides a disk service for testing or local deployments, but the focus is on cloud storage.
+
+Files can be uploaded from the server to the cloud or directly from the client to the cloud.
+
+Image files can furthermore be transformed using on-demand variants for quality, aspect ratio, size, or any other [MiniMagick](https://github.com/minimagick/minimagick) supported transformation.
+
+## Compared to other storage solutions
+
+A key difference to how Active Storage works compared to other attachment solutions in Rails is through the use of built-in [Blob](https://github.com/rails/rails/blob/master/activestorage/app/models/active_storage/blob.rb) and [Attachment](https://github.com/rails/rails/blob/master/activestorage/app/models/active_storage/attachment.rb) models (backed by Active Record). This means existing application models do not need to be modified with additional columns to associate with files. Active Storage uses polymorphic associations via the `Attachment` join model, which then connects to the actual `Blob`.
+
+`Blob` models store attachment metadata (filename, content-type, etc.), and their identifier key in the storage service. Blob models do not store the actual binary data. They are intended to be immutable in spirit. One file, one blob. You can associate the same blob with multiple application models as well. And if you want to do transformations of a given `Blob`, the idea is that you'll simply create a new one, rather than attempt to mutate the existing one (though of course you can delete the previous version later if you don't need it).
+
+## Installation
+
+Run `rails active_storage:install` to copy over active_storage migrations.
+
+## Examples
+
+One attachment:
+
+```ruby
+class User < ApplicationRecord
+  # Associates an attachment and a blob. When the user is destroyed they are
+  # purged by default (models destroyed, and resource files deleted).
+  has_one_attached :avatar
+end
+
+# Attach an avatar to the user.
+user.avatar.attach(io: File.open("/path/to/face.jpg"), filename: "face.jpg", content_type: "image/jpg")
+
+# Does the user have an avatar?
+user.avatar.attached? # => true
+
+# Synchronously destroy the avatar and actual resource files.
+user.avatar.purge
+
+# Destroy the associated models and actual resource files async, via Active Job.
+user.avatar.purge_later
+
+# Does the user have an avatar?
+user.avatar.attached? # => false
+
+# Generate a permanent URL for the blob that points to the application.
+# Upon access, a redirect to the actual service endpoint is returned.
+# This indirection decouples the public URL from the actual one, and
+# allows for example mirroring attachments in different services for
+# high-availability. The redirection has an HTTP expiration of 5 min.
+url_for(user.avatar)
+
+class AvatarsController < ApplicationController
+  def update
+    # params[:avatar] contains a ActionDispatch::Http::UploadedFile object
+    Current.user.avatar.attach(params.require(:avatar))
+    redirect_to Current.user
+  end
+end
+```
+
+Many attachments:
+
+```ruby
+class Message < ApplicationRecord
+  has_many_attached :images
+end
+```
+
+```erb
+<%= form_with model: @message, local: true do |form| %>
+  <%= form.text_field :title, placeholder: "Title" %><br>
+  <%= form.text_area :content %><br><br>
+
+  <%= form.file_field :images, multiple: true %><br>
+  <%= form.submit %>
+<% end %>
+```
+
+```ruby
+class MessagesController < ApplicationController
+  def index
+    # Use the built-in with_attached_images scope to avoid N+1
+    @messages = Message.all.with_attached_images
+  end
+
+  def create
+    message = Message.create! params.require(:message).permit(:title, :content)
+    message.images.attach(params[:message][:images])
+    redirect_to message
+  end
+
+  def show
+    @message = Message.find(params[:id])
+  end
+end
+```
+
+Variation of image attachment:
+
+```erb
+<%# Hitting the variant URL will lazy transform the original blob and then redirect to its new service location %>
+<%= image_tag user.avatar.variant(resize: "100x100") %>
+```
+
+## Direct uploads
+
+Active Storage, with its included JavaScript library, supports uploading directly from the client to the cloud.
+
+### Direct upload installation
+
+1. Include `activestorage.js` in your application's JavaScript bundle.
+
+    Using the asset pipeline:
+    ```js
+    //= require activestorage
+    ```
+    Using the npm package:
+    ```js
+    import * as ActiveStorage from "activestorage"
+    ActiveStorage.start()
+    ```
+2. Annotate file inputs with the direct upload URL.
+
+    ```ruby
+    <%= form.file_field :attachments, multiple: true, direct_upload: true %>
+    ```
+3. That's it! Uploads begin upon form submission.
+
+### Direct upload JavaScript events
+
+| Event name | Event target | Event data (`event.detail`) | Description |
+| --- | --- | --- | --- |
+| `direct-uploads:start` | `<form>` | None | A form containing files for direct upload fields was submitted. |
+| `direct-upload:initialize` | `<input>` | `{id, file}` | Dispatched for every file after form submission. |
+| `direct-upload:start` | `<input>` | `{id, file}` | A direct upload is starting. |
+| `direct-upload:before-blob-request` | `<input>` | `{id, file, xhr}` | Before making a request to your application for direct upload metadata. |
+| `direct-upload:before-storage-request` | `<input>` | `{id, file, xhr}` | Before making a request to store a file. |
+| `direct-upload:progress` | `<input>` | `{id, file, progress}` | As requests to store files progress. |
+| `direct-upload:error` | `<input>` | `{id, file, error}` | An error occurred. An `alert` will display unless this event is canceled. |
+| `direct-upload:end` | `<input>` | `{id, file}` | A direct upload has ended. |
+| `direct-uploads:end` | `<form>` | None | All direct uploads have ended. |
+
+## License
+
+Active Storage is released under the [MIT License](https://opensource.org/licenses/MIT).
+
+## Support
+
+API documentation is at:
+
+* http://api.rubyonrails.org
+
+Bug reports for the Ruby on Rails project can be filed here:
+
+* https://github.com/rails/rails/issues
+
+Feature requests should be discussed on the rails-core mailing list here:
+
+* https://groups.google.com/forum/?fromgroups#!forum/rubyonrails-core
diff --git a/activestorage/Rakefile b/activestorage/Rakefile
new file mode 100644
index 0000000000..2aa4d2a76f
--- /dev/null
+++ b/activestorage/Rakefile
@@ -0,0 +1,16 @@
+# frozen_string_literal: true
+
+require "bundler/setup"
+require "bundler/gem_tasks"
+require "rake/testtask"
+
+Rake::TestTask.new do |test|
+  test.libs << "app/controllers"
+  test.libs << "test"
+  test.test_files = FileList["test/**/*_test.rb"]
+  test.warning = false
+end
+
+task :package
+
+task default: :test
diff --git a/activestorage/activestorage.gemspec b/activestorage/activestorage.gemspec
new file mode 100644
index 0000000000..7f7f1a26ac
--- /dev/null
+++ b/activestorage/activestorage.gemspec
@@ -0,0 +1,30 @@
+# frozen_string_literal: true
+
+version = File.read(File.expand_path("../RAILS_VERSION", __dir__)).strip
+
+Gem::Specification.new do |s|
+  s.platform    = Gem::Platform::RUBY
+  s.name        = "activestorage"
+  s.version     = version
+  s.summary     = "Local and cloud file storage framework."
+  s.description = "Attach cloud and local files in Rails applications."
+
+  s.required_ruby_version = ">= 2.2.2"
+
+  s.license = "MIT"
+
+  s.author   = "David Heinemeier Hansson"
+  s.email    = "david@loudthinking.com"
+  s.homepage = "http://rubyonrails.org"
+
+  s.files        = Dir["CHANGELOG.md", "MIT-LICENSE", "README.md", "lib/**/*", "app/**/*", "config/**/*", "db/**/*"]
+  s.require_path = "lib"
+
+  s.metadata = {
+    "source_code_uri" => "https://github.com/rails/rails/tree/v#{version}/activestorage",
+    "changelog_uri"   => "https://github.com/rails/rails/blob/v#{version}/activestorage/CHANGELOG.md"
+  }
+
+  s.add_dependency "actionpack", version
+  s.add_dependency "activerecord", version
+end
diff --git a/activestorage/app/assets/javascripts/activestorage.js b/activestorage/app/assets/javascripts/activestorage.js
new file mode 100644
index 0000000000..946217e541
--- /dev/null
+++ b/activestorage/app/assets/javascripts/activestorage.js
@@ -0,0 +1 @@
+!function(t,e){"object"==typeof exports&&"object"==typeof module?module.exports=e():"function"==typeof define&&define.amd?define([],e):"object"==typeof exports?exports.ActiveStorage=e():t.ActiveStorage=e()}(this,function(){return function(t){function e(n){if(r[n])return r[n].exports;var i=r[n]={i:n,l:!1,exports:{}};return t[n].call(i.exports,i,i.exports,e),i.l=!0,i.exports}var r={};return e.m=t,e.c=r,e.d=function(t,r,n){e.o(t,r)||Object.defineProperty(t,r,{configurable:!1,enumerable:!0,get:n})},e.n=function(t){var r=t&&t.__esModule?function(){return t.default}:function(){return t};return e.d(r,"a",r),r},e.o=function(t,e){return Object.prototype.hasOwnProperty.call(t,e)},e.p="",e(e.s=2)}([function(t,e,r){"use strict";function n(t){var e=a(document.head,'meta[name="'+t+'"]');if(e)return e.getAttribute("content")}function i(t,e){return"string"==typeof t&&(e=t,t=document),o(t.querySelectorAll(e))}function a(t,e){return"string"==typeof t&&(e=t,t=document),t.querySelector(e)}function u(t,e){var r=arguments.length>2&&void 0!==arguments[2]?arguments[2]:{},n=r.bubbles,i=r.cancelable,a=r.detail,u=document.createEvent("Event");return u.initEvent(e,n||!0,i||!0),u.detail=a||{},t.dispatchEvent(u),u}function o(t){return Array.isArray(t)?t:Array.from?Array.from(t):[].slice.call(t)}e.d=n,e.c=i,e.b=a,e.a=u,e.e=o},function(t,e,r){"use strict";function n(t,e){if(!(t instanceof e))throw new TypeError("Cannot call a class as a function")}function i(t,e){if(t&&"function"==typeof t[e]){for(var r=arguments.length,n=Array(r>2?r-2:0),i=2;i<r;i++)n[i-2]=arguments[i];return t[e].apply(t,n)}}r.d(e,"a",function(){return c});var a=r(6),u=r(8),o=r(9),s=function(){function t(t,e){for(var r=0;r<e.length;r++){var n=e[r];n.enumerable=n.enumerable||!1,n.configurable=!0,"value"in n&&(n.writable=!0),Object.defineProperty(t,n.key,n)}}return function(e,r,n){return r&&t(e.prototype,r),n&&t(e,n),e}}(),f=0,c=function(){function t(e,r,i){n(this,t),this.id=++f,this.file=e,this.url=r,this.delegate=i}return s(t,[{key:"create",value:function(t){var e=this;a.a.create(this.file,function(r,n){var a=new u.a(e.file,n,e.url);i(e.delegate,"directUploadWillCreateBlobWithXHR",a.xhr),a.create(function(r){if(r)t(r);else{var n=new o.a(a);i(e.delegate,"directUploadWillStoreFileWithXHR",n.xhr),n.create(function(e){e?t(e):t(null,a.toJSON())})}})})}}]),t}()},function(t,e,r){"use strict";function n(){window.ActiveStorage&&Object(i.a)()}Object.defineProperty(e,"__esModule",{value:!0});var i=r(3),a=r(1);r.d(e,"start",function(){return i.a}),r.d(e,"DirectUpload",function(){return a.a}),setTimeout(n,1)},function(t,e,r){"use strict";function n(){d||(d=!0,document.addEventListener("submit",i),document.addEventListener("ajax:before",a))}function i(t){u(t)}function a(t){"FORM"==t.target.tagName&&u(t)}function u(t){var e=t.target;if(e.hasAttribute(l))return void t.preventDefault();var r=new 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t.buff=f(t.buff,!0),d.prototype.setState.call(this,t)},d.ArrayBuffer.prototype.destroy=d.prototype.destroy,d.ArrayBuffer.prototype._finish=d.prototype._finish,d.ArrayBuffer.hash=function(t,e){var r=a(new Uint8Array(t)),n=o(r);return e?l(n):n},d})},function(t,e,r){"use strict";function n(t,e){if(!(t instanceof e))throw new TypeError("Cannot call a class as a function")}r.d(e,"a",function(){return u});var i=r(0),a=function(){function t(t,e){for(var r=0;r<e.length;r++){var n=e[r];n.enumerable=n.enumerable||!1,n.configurable=!0,"value"in n&&(n.writable=!0),Object.defineProperty(t,n.key,n)}}return function(e,r,n){return r&&t(e.prototype,r),n&&t(e,n),e}}(),u=function(){function t(e,r,a){var u=this;n(this,t),this.file=e,this.attributes={filename:e.name,content_type:e.type,byte_size:e.size,checksum:r},this.xhr=new XMLHttpRequest,this.xhr.open("POST",a,!0),this.xhr.responseType="json",this.xhr.setRequestHeader("Content-Type","application/json"),this.xhr.setRequestHeader("Accept","application/json"),this.xhr.setRequestHeader("X-Requested-With","XMLHttpRequest"),this.xhr.setRequestHeader("X-CSRF-Token",Object(i.d)("csrf-token")),this.xhr.addEventListener("load",function(t){return u.requestDidLoad(t)}),this.xhr.addEventListener("error",function(t){return u.requestDidError(t)})}return a(t,[{key:"create",value:function(t){this.callback=t,this.xhr.send(JSON.stringify({blob:this.attributes}))}},{key:"requestDidLoad",value:function(t){if(this.status>=200&&this.status<300){var e=this.response,r=e.direct_upload;delete e.direct_upload,this.attributes=e,this.directUploadData=r,this.callback(null,this.toJSON())}else this.requestDidError(t)}},{key:"requestDidError",value:function(t){this.callback('Error creating Blob for "'+this.file.name+'". Status: '+this.status)}},{key:"toJSON",value:function(){var t={};for(var e in this.attributes)t[e]=this.attributes[e];return t}},{key:"status",get:function(){return this.xhr.status}},{key:"response",get:function(){var t=this.xhr,e=t.responseType,r=t.response;return"json"==e?r:JSON.parse(r)}}]),t}()},function(t,e,r){"use strict";function n(t,e){if(!(t instanceof e))throw new TypeError("Cannot call a class as a function")}r.d(e,"a",function(){return a});var i=function(){function t(t,e){for(var r=0;r<e.length;r++){var n=e[r];n.enumerable=n.enumerable||!1,n.configurable=!0,"value"in n&&(n.writable=!0),Object.defineProperty(t,n.key,n)}}return function(e,r,n){return r&&t(e.prototype,r),n&&t(e,n),e}}(),a=function(){function t(e){var r=this;n(this,t),this.blob=e,this.file=e.file;var i=e.directUploadData,a=i.url,u=i.headers;this.xhr=new XMLHttpRequest,this.xhr.open("PUT",a,!0),this.xhr.responseType="text";for(var o in u)this.xhr.setRequestHeader(o,u[o]);this.xhr.addEventListener("load",function(t){return r.requestDidLoad(t)}),this.xhr.addEventListener("error",function(t){return r.requestDidError(t)})}return i(t,[{key:"create",value:function(t){this.callback=t,this.xhr.send(this.file)}},{key:"requestDidLoad",value:function(t){var e=this.xhr,r=e.status,n=e.response;r>=200&&r<300?this.callback(null,n):this.requestDidError(t)}},{key:"requestDidError",value:function(t){this.callback('Error storing "'+this.file.name+'". Status: '+this.xhr.status)}}]),t}()}])});
\ No newline at end of file
diff --git a/activestorage/app/controllers/active_storage/blobs_controller.rb b/activestorage/app/controllers/active_storage/blobs_controller.rb
new file mode 100644
index 0000000000..fa44131048
--- /dev/null
+++ b/activestorage/app/controllers/active_storage/blobs_controller.rb
@@ -0,0 +1,14 @@
+# frozen_string_literal: true
+
+# Take a signed permanent reference for a blob and turn it into an expiring service URL for download.
+# Note: These URLs are publicly accessible. If you need to enforce access protection beyond the
+# security-through-obscurity factor of the signed blob references, you'll need to implement your own
+# authenticated redirection controller.
+class ActiveStorage::BlobsController < ActionController::Base
+  include ActiveStorage::SetBlob
+
+  def show
+    expires_in ActiveStorage::Blob.service.url_expires_in
+    redirect_to @blob.service_url(disposition: params[:disposition])
+  end
+end
diff --git a/activestorage/app/controllers/active_storage/direct_uploads_controller.rb b/activestorage/app/controllers/active_storage/direct_uploads_controller.rb
new file mode 100644
index 0000000000..205d173648
--- /dev/null
+++ b/activestorage/app/controllers/active_storage/direct_uploads_controller.rb
@@ -0,0 +1,23 @@
+# frozen_string_literal: true
+
+# Creates a new blob on the server side in anticipation of a direct-to-service upload from the client side.
+# When the client-side upload is completed, the signed_blob_id can be submitted as part of the form to reference
+# the blob that was created up front.
+class ActiveStorage::DirectUploadsController < ActionController::Base
+  def create
+    blob = ActiveStorage::Blob.create_before_direct_upload!(blob_args)
+    render json: direct_upload_json(blob)
+  end
+
+  private
+    def blob_args
+      params.require(:blob).permit(:filename, :byte_size, :checksum, :content_type, :metadata).to_h.symbolize_keys
+    end
+
+    def direct_upload_json(blob)
+      blob.as_json(methods: :signed_id).merge(direct_upload: {
+        url: blob.service_url_for_direct_upload,
+        headers: blob.service_headers_for_direct_upload
+      })
+    end
+end
diff --git a/activestorage/app/controllers/active_storage/disk_controller.rb b/activestorage/app/controllers/active_storage/disk_controller.rb
new file mode 100644
index 0000000000..a7e10c0696
--- /dev/null
+++ b/activestorage/app/controllers/active_storage/disk_controller.rb
@@ -0,0 +1,51 @@
+# frozen_string_literal: true
+
+# Serves files stored with the disk service in the same way that the cloud services do.
+# This means using expiring, signed URLs that are meant for immediate access, not permanent linking.
+# Always go through the BlobsController, or your own authenticated controller, rather than directly
+# to the service url.
+class ActiveStorage::DiskController < ActionController::Base
+  skip_forgery_protection if default_protect_from_forgery
+
+  def show
+    if key = decode_verified_key
+      send_data disk_service.download(key),
+        disposition: params[:disposition], content_type: params[:content_type]
+    else
+      head :not_found
+    end
+  end
+
+  def update
+    if token = decode_verified_token
+      if acceptable_content?(token)
+        disk_service.upload token[:key], request.body, checksum: token[:checksum]
+      else
+        head :unprocessable_entity
+      end
+    else
+      head :not_found
+    end
+  rescue ActiveStorage::IntegrityError
+    head :unprocessable_entity
+  end
+
+  private
+    def disk_service
+      ActiveStorage::Blob.service
+    end
+
+
+    def decode_verified_key
+      ActiveStorage.verifier.verified(params[:encoded_key], purpose: :blob_key)
+    end
+
+
+    def decode_verified_token
+      ActiveStorage.verifier.verified(params[:encoded_token], purpose: :blob_token)
+    end
+
+    def acceptable_content?(token)
+      token[:content_type] == request.content_type && token[:content_length] == request.content_length
+    end
+end
diff --git a/activestorage/app/controllers/active_storage/previews_controller.rb b/activestorage/app/controllers/active_storage/previews_controller.rb
new file mode 100644
index 0000000000..aa7ef58ca4
--- /dev/null
+++ b/activestorage/app/controllers/active_storage/previews_controller.rb
@@ -0,0 +1,10 @@
+# frozen_string_literal: true
+
+class ActiveStorage::PreviewsController < ActionController::Base
+  include ActiveStorage::SetBlob
+
+  def show
+    expires_in ActiveStorage::Blob.service.url_expires_in
+    redirect_to ActiveStorage::Preview.new(@blob, params[:variation_key]).processed.service_url(disposition: params[:disposition])
+  end
+end
diff --git a/activestorage/app/controllers/active_storage/variants_controller.rb b/activestorage/app/controllers/active_storage/variants_controller.rb
new file mode 100644
index 0000000000..e8f8dd592d
--- /dev/null
+++ b/activestorage/app/controllers/active_storage/variants_controller.rb
@@ -0,0 +1,14 @@
+# frozen_string_literal: true
+
+# Take a signed permanent reference for a variant and turn it into an expiring service URL for download.
+# Note: These URLs are publicly accessible. If you need to enforce access protection beyond the
+# security-through-obscurity factor of the signed blob and variation reference, you'll need to implement your own
+# authenticated redirection controller.
+class ActiveStorage::VariantsController < ActionController::Base
+  include ActiveStorage::SetBlob
+
+  def show
+    expires_in ActiveStorage::Blob.service.url_expires_in
+    redirect_to ActiveStorage::Variant.new(@blob, params[:variation_key]).processed.service_url(disposition: params[:disposition])
+  end
+end
diff --git a/activestorage/app/controllers/concerns/active_storage/set_blob.rb b/activestorage/app/controllers/concerns/active_storage/set_blob.rb
new file mode 100644
index 0000000000..b0f3d97a66
--- /dev/null
+++ b/activestorage/app/controllers/concerns/active_storage/set_blob.rb
@@ -0,0 +1,16 @@
+# frozen_string_literal: true
+
+module ActiveStorage::SetBlob
+  extend ActiveSupport::Concern
+
+  included do
+    before_action :set_blob
+  end
+
+  private
+    def set_blob
+      @blob = ActiveStorage::Blob.find_signed(params[:signed_blob_id] || params[:signed_id])
+    rescue ActiveSupport::MessageVerifier::InvalidSignature
+      head :not_found
+    end
+end
diff --git a/activestorage/app/javascript/activestorage/blob_record.js b/activestorage/app/javascript/activestorage/blob_record.js
new file mode 100644
index 0000000000..ff847892b2
--- /dev/null
+++ b/activestorage/app/javascript/activestorage/blob_record.js
@@ -0,0 +1,68 @@
+import { getMetaValue } from "./helpers"
+
+export class BlobRecord {
+  constructor(file, checksum, url) {
+    this.file = file
+
+    this.attributes = {
+      filename: file.name,
+      content_type: file.type,
+      byte_size: file.size,
+      checksum: checksum
+    }
+
+    this.xhr = new XMLHttpRequest
+    this.xhr.open("POST", url, true)
+    this.xhr.responseType = "json"
+    this.xhr.setRequestHeader("Content-Type", "application/json")
+    this.xhr.setRequestHeader("Accept", "application/json")
+    this.xhr.setRequestHeader("X-Requested-With", "XMLHttpRequest")
+    this.xhr.setRequestHeader("X-CSRF-Token", getMetaValue("csrf-token"))
+    this.xhr.addEventListener("load", event => this.requestDidLoad(event))
+    this.xhr.addEventListener("error", event => this.requestDidError(event))
+  }
+
+  get status() {
+    return this.xhr.status
+  }
+
+  get response() {
+    const { responseType, response } = this.xhr
+    if (responseType == "json") {
+      return response
+    } else {
+      // Shim for IE 11: https://connect.microsoft.com/IE/feedback/details/794808
+      return JSON.parse(response)
+    }
+  }
+
+  create(callback) {
+    this.callback = callback
+    this.xhr.send(JSON.stringify({ blob: this.attributes }))
+  }
+
+  requestDidLoad(event) {
+    if (this.status >= 200 && this.status < 300) {
+      const { response } = this
+      const { direct_upload } = response
+      delete response.direct_upload
+      this.attributes = response
+      this.directUploadData = direct_upload
+      this.callback(null, this.toJSON())
+    } else {
+      this.requestDidError(event)
+    }
+  }
+
+  requestDidError(event) {
+    this.callback(`Error creating Blob for "${this.file.name}". Status: ${this.status}`)
+  }
+
+  toJSON() {
+    const result = {}
+    for (const key in this.attributes) {
+      result[key] = this.attributes[key]
+    }
+    return result
+  }
+}
diff --git a/activestorage/app/javascript/activestorage/blob_upload.js b/activestorage/app/javascript/activestorage/blob_upload.js
new file mode 100644
index 0000000000..180a7415e7
--- /dev/null
+++ b/activestorage/app/javascript/activestorage/blob_upload.js
@@ -0,0 +1,35 @@
+export class BlobUpload {
+  constructor(blob) {
+    this.blob = blob
+    this.file = blob.file
+
+    const { url, headers } = blob.directUploadData
+
+    this.xhr = new XMLHttpRequest
+    this.xhr.open("PUT", url, true)
+    this.xhr.responseType = "text"
+    for (const key in headers) {
+      this.xhr.setRequestHeader(key, headers[key])
+    }
+    this.xhr.addEventListener("load", event => this.requestDidLoad(event))
+    this.xhr.addEventListener("error", event => this.requestDidError(event))
+  }
+
+  create(callback) {
+    this.callback = callback
+    this.xhr.send(this.file)
+  }
+
+  requestDidLoad(event) {
+    const { status, response } = this.xhr
+    if (status >= 200 && status < 300) {
+      this.callback(null, response)
+    } else {
+      this.requestDidError(event)
+    }
+  }
+
+  requestDidError(event) {
+    this.callback(`Error storing "${this.file.name}". Status: ${this.xhr.status}`)
+  }
+}
diff --git a/activestorage/app/javascript/activestorage/direct_upload.js b/activestorage/app/javascript/activestorage/direct_upload.js
new file mode 100644
index 0000000000..7085e0a4ab
--- /dev/null
+++ b/activestorage/app/javascript/activestorage/direct_upload.js
@@ -0,0 +1,42 @@
+import { FileChecksum } from "./file_checksum"
+import { BlobRecord } from "./blob_record"
+import { BlobUpload } from "./blob_upload"
+
+let id = 0
+
+export class DirectUpload {
+  constructor(file, url, delegate) {
+    this.id = ++id
+    this.file = file
+    this.url = url
+    this.delegate = delegate
+  }
+
+  create(callback) {
+    FileChecksum.create(this.file, (error, checksum) => {
+      const blob = new BlobRecord(this.file, checksum, this.url)
+      notify(this.delegate, "directUploadWillCreateBlobWithXHR", blob.xhr)
+      blob.create(error => {
+        if (error) {
+          callback(error)
+        } else {
+          const upload = new BlobUpload(blob)
+          notify(this.delegate, "directUploadWillStoreFileWithXHR", upload.xhr)
+          upload.create(error => {
+            if (error) {
+              callback(error)
+            } else {
+              callback(null, blob.toJSON())
+            }
+          })
+        }
+      })
+    })
+  }
+}
+
+function notify(object, methodName, ...messages) {
+  if (object && typeof object[methodName] == "function") {
+    return object[methodName](...messages)
+  }
+}
diff --git a/activestorage/app/javascript/activestorage/direct_upload_controller.js b/activestorage/app/javascript/activestorage/direct_upload_controller.js
new file mode 100644
index 0000000000..987050889a
--- /dev/null
+++ b/activestorage/app/javascript/activestorage/direct_upload_controller.js
@@ -0,0 +1,67 @@
+import { DirectUpload } from "./direct_upload"
+import { dispatchEvent } from "./helpers"
+
+export class DirectUploadController {
+  constructor(input, file) {
+    this.input = input
+    this.file = file
+    this.directUpload = new DirectUpload(this.file, this.url, this)
+    this.dispatch("initialize")
+  }
+
+  start(callback) {
+    const hiddenInput = document.createElement("input")
+    hiddenInput.type = "hidden"
+    hiddenInput.name = this.input.name
+    this.input.insertAdjacentElement("beforebegin", hiddenInput)
+
+    this.dispatch("start")
+
+    this.directUpload.create((error, attributes) => {
+      if (error) {
+        hiddenInput.parentNode.removeChild(hiddenInput)
+        this.dispatchError(error)
+      } else {
+        hiddenInput.value = attributes.signed_id
+      }
+
+      this.dispatch("end")
+      callback(error)
+    })
+  }
+
+  uploadRequestDidProgress(event) {
+    const progress = event.loaded / event.total * 100
+    if (progress) {
+      this.dispatch("progress", { progress })
+    }
+  }
+
+  get url() {
+    return this.input.getAttribute("data-direct-upload-url")
+  }
+
+  dispatch(name, detail = {}) {
+    detail.file = this.file
+    detail.id = this.directUpload.id
+    return dispatchEvent(this.input, `direct-upload:${name}`, { detail })
+  }
+
+  dispatchError(error) {
+    const event = this.dispatch("error", { error })
+    if (!event.defaultPrevented) {
+      alert(error)
+    }
+  }
+
+  // DirectUpload delegate
+
+  directUploadWillCreateBlobWithXHR(xhr) {
+    this.dispatch("before-blob-request", { xhr })
+  }
+
+  directUploadWillStoreFileWithXHR(xhr) {
+    this.dispatch("before-storage-request", { xhr })
+    xhr.upload.addEventListener("progress", event => this.uploadRequestDidProgress(event))
+  }
+}
diff --git a/activestorage/app/javascript/activestorage/direct_uploads_controller.js b/activestorage/app/javascript/activestorage/direct_uploads_controller.js
new file mode 100644
index 0000000000..94b89c9119
--- /dev/null
+++ b/activestorage/app/javascript/activestorage/direct_uploads_controller.js
@@ -0,0 +1,50 @@
+import { DirectUploadController } from "./direct_upload_controller"
+import { findElements, dispatchEvent, toArray } from "./helpers"
+
+const inputSelector = "input[type=file][data-direct-upload-url]:not([disabled])"
+
+export class DirectUploadsController {
+  constructor(form) {
+    this.form = form
+    this.inputs = findElements(form, inputSelector).filter(input => input.files.length)
+  }
+
+  start(callback) {
+    const controllers = this.createDirectUploadControllers()
+
+    const startNextController = () => {
+      const controller = controllers.shift()
+      if (controller) {
+        controller.start(error => {
+          if (error) {
+            callback(error)
+            this.dispatch("end")
+          } else {
+            startNextController()
+          }
+        })
+      } else {
+        callback()
+        this.dispatch("end")
+      }
+    }
+
+    this.dispatch("start")
+    startNextController()
+  }
+
+  createDirectUploadControllers() {
+    const controllers = []
+    this.inputs.forEach(input => {
+      toArray(input.files).forEach(file => {
+        const controller = new DirectUploadController(input, file)
+        controllers.push(controller)
+      })
+    })
+    return controllers
+  }
+
+  dispatch(name, detail = {}) {
+    return dispatchEvent(this.form, `direct-uploads:${name}`, { detail })
+  }
+}
diff --git a/activestorage/app/javascript/activestorage/file_checksum.js b/activestorage/app/javascript/activestorage/file_checksum.js
new file mode 100644
index 0000000000..ffaec1a128
--- /dev/null
+++ b/activestorage/app/javascript/activestorage/file_checksum.js
@@ -0,0 +1,53 @@
+import SparkMD5 from "spark-md5"
+
+const fileSlice = File.prototype.slice || File.prototype.mozSlice || File.prototype.webkitSlice
+
+export class FileChecksum {
+  static create(file, callback) {
+    const instance = new FileChecksum(file)
+    instance.create(callback)
+  }
+
+  constructor(file) {
+    this.file = file
+    this.chunkSize = 2097152 // 2MB
+    this.chunkCount = Math.ceil(this.file.size / this.chunkSize)
+    this.chunkIndex = 0
+  }
+
+  create(callback) {
+    this.callback = callback
+    this.md5Buffer = new SparkMD5.ArrayBuffer
+    this.fileReader = new FileReader
+    this.fileReader.addEventListener("load", event => this.fileReaderDidLoad(event))
+    this.fileReader.addEventListener("error", event => this.fileReaderDidError(event))
+    this.readNextChunk()
+  }
+
+  fileReaderDidLoad(event) {
+    this.md5Buffer.append(event.target.result)
+
+    if (!this.readNextChunk()) {
+      const binaryDigest = this.md5Buffer.end(true)
+      const base64digest = btoa(binaryDigest)
+      this.callback(null, base64digest)
+    }
+  }
+
+  fileReaderDidError(event) {
+    this.callback(`Error reading ${this.file.name}`)
+  }
+
+  readNextChunk() {
+    if (this.chunkIndex < this.chunkCount) {
+      const start = this.chunkIndex * this.chunkSize
+      const end = Math.min(start + this.chunkSize, this.file.size)
+      const bytes = fileSlice.call(this.file, start, end)
+      this.fileReader.readAsArrayBuffer(bytes)
+      this.chunkIndex++
+      return true
+    } else {
+      return false
+    }
+  }
+}
diff --git a/activestorage/app/javascript/activestorage/helpers.js b/activestorage/app/javascript/activestorage/helpers.js
new file mode 100644
index 0000000000..52fec8f6f1
--- /dev/null
+++ b/activestorage/app/javascript/activestorage/helpers.js
@@ -0,0 +1,42 @@
+export function getMetaValue(name) {
+  const element = findElement(document.head, `meta[name="${name}"]`)
+  if (element) {
+    return element.getAttribute("content")
+  }
+}
+
+export function findElements(root, selector) {
+  if (typeof root == "string") {
+    selector = root
+    root = document
+  }
+  const elements = root.querySelectorAll(selector)
+  return toArray(elements)
+}
+
+export function findElement(root, selector) {
+  if (typeof root == "string") {
+    selector = root
+    root = document
+  }
+  return root.querySelector(selector)
+}
+
+export function dispatchEvent(element, type, eventInit = {}) {
+  const { bubbles, cancelable, detail } = eventInit
+  const event = document.createEvent("Event")
+  event.initEvent(type, bubbles || true, cancelable || true)
+  event.detail = detail || {}
+  element.dispatchEvent(event)
+  return event
+}
+
+export function toArray(value) {
+  if (Array.isArray(value)) {
+    return value
+  } else if (Array.from) {
+    return Array.from(value)
+  } else {
+    return [].slice.call(value)
+  }
+}
diff --git a/activestorage/app/javascript/activestorage/index.js b/activestorage/app/javascript/activestorage/index.js
new file mode 100644
index 0000000000..a340008fb9
--- /dev/null
+++ b/activestorage/app/javascript/activestorage/index.js
@@ -0,0 +1,11 @@
+import { start } from "./ujs"
+import { DirectUpload } from "./direct_upload"
+export { start, DirectUpload }
+
+function autostart() {
+  if (window.ActiveStorage) {
+    start()
+  }
+}
+
+setTimeout(autostart, 1)
diff --git a/activestorage/app/javascript/activestorage/ujs.js b/activestorage/app/javascript/activestorage/ujs.js
new file mode 100644
index 0000000000..1dda02936f
--- /dev/null
+++ b/activestorage/app/javascript/activestorage/ujs.js
@@ -0,0 +1,75 @@
+import { DirectUploadsController } from "./direct_uploads_controller"
+import { findElement } from "./helpers"
+
+const processingAttribute = "data-direct-uploads-processing"
+let started = false
+
+export function start() {
+  if (!started) {
+    started = true
+    document.addEventListener("submit", didSubmitForm)
+    document.addEventListener("ajax:before", didSubmitRemoteElement)
+  }
+}
+
+function didSubmitForm(event) {
+  handleFormSubmissionEvent(event)
+}
+
+function didSubmitRemoteElement(event) {
+  if (event.target.tagName == "FORM") {
+    handleFormSubmissionEvent(event)
+  }
+}
+
+function handleFormSubmissionEvent(event) {
+  const form = event.target
+
+  if (form.hasAttribute(processingAttribute)) {
+    event.preventDefault()
+    return
+  }
+
+  const controller = new DirectUploadsController(form)
+  const { inputs } = controller
+
+  if (inputs.length) {
+    event.preventDefault()
+    form.setAttribute(processingAttribute, "")
+    inputs.forEach(disable)
+    controller.start(error => {
+      form.removeAttribute(processingAttribute)
+      if (error) {
+        inputs.forEach(enable)
+      } else {
+        submitForm(form)
+      }
+    })
+  }
+}
+
+function submitForm(form) {
+  let button = findElement(form, "input[type=submit]")
+  if (button) {
+    const { disabled } = button
+    button.disabled = false
+    button.focus()
+    button.click()
+    button.disabled = disabled
+  } else {
+    button = document.createElement("input")
+    button.type = "submit"
+    button.style = "display:none"
+    form.appendChild(button)
+    button.click()
+    form.removeChild(button)
+  }
+}
+
+function disable(input) {
+  input.disabled = true
+}
+
+function enable(input) {
+  input.disabled = false
+}
diff --git a/activestorage/app/jobs/active_storage/analyze_job.rb b/activestorage/app/jobs/active_storage/analyze_job.rb
new file mode 100644
index 0000000000..2a952f9f74
--- /dev/null
+++ b/activestorage/app/jobs/active_storage/analyze_job.rb
@@ -0,0 +1,8 @@
+# frozen_string_literal: true
+
+# Provides asynchronous analysis of ActiveStorage::Blob records via ActiveStorage::Blob#analyze_later.
+class ActiveStorage::AnalyzeJob < ActiveStorage::BaseJob
+  def perform(blob)
+    blob.analyze
+  end
+end
diff --git a/activestorage/app/jobs/active_storage/base_job.rb b/activestorage/app/jobs/active_storage/base_job.rb
new file mode 100644
index 0000000000..6caab42a2d
--- /dev/null
+++ b/activestorage/app/jobs/active_storage/base_job.rb
@@ -0,0 +1,5 @@
+# frozen_string_literal: true
+
+class ActiveStorage::BaseJob < ActiveJob::Base
+  queue_as { ActiveStorage.queue }
+end
diff --git a/activestorage/app/jobs/active_storage/purge_job.rb b/activestorage/app/jobs/active_storage/purge_job.rb
new file mode 100644
index 0000000000..98874d2250
--- /dev/null
+++ b/activestorage/app/jobs/active_storage/purge_job.rb
@@ -0,0 +1,11 @@
+# frozen_string_literal: true
+
+# Provides asynchronous purging of ActiveStorage::Blob records via ActiveStorage::Blob#purge_later.
+class ActiveStorage::PurgeJob < ActiveStorage::BaseJob
+  # FIXME: Limit this to a custom ActiveStorage error
+  retry_on StandardError
+
+  def perform(blob)
+    blob.purge
+  end
+end
diff --git a/activestorage/app/models/active_storage/attachment.rb b/activestorage/app/models/active_storage/attachment.rb
new file mode 100644
index 0000000000..9f61a5dbf3
--- /dev/null
+++ b/activestorage/app/models/active_storage/attachment.rb
@@ -0,0 +1,35 @@
+# frozen_string_literal: true
+
+require "active_support/core_ext/module/delegation"
+
+# Attachments associate records with blobs. Usually that's a one record-many blobs relationship,
+# but it is possible to associate many different records with the same blob. If you're doing that,
+# you'll want to declare with <tt>has_one/many_attached :thingy, dependent: false</tt>, so that destroying
+# any one record won't destroy the blob as well. (Then you'll need to do your own garbage collecting, though).
+class ActiveStorage::Attachment < ActiveRecord::Base
+  self.table_name = "active_storage_attachments"
+
+  belongs_to :record, polymorphic: true, touch: true
+  belongs_to :blob, class_name: "ActiveStorage::Blob"
+
+  delegate_missing_to :blob
+
+  after_create_commit :analyze_blob_later
+
+  # Synchronously purges the blob (deletes it from the configured service) and destroys the attachment.
+  def purge
+    blob.purge
+    destroy
+  end
+
+  # Destroys the attachment and asynchronously purges the blob (deletes it from the configured service).
+  def purge_later
+    blob.purge_later
+    destroy
+  end
+
+  private
+    def analyze_blob_later
+      blob.analyze_later unless blob.analyzed?
+    end
+end
diff --git a/activestorage/app/models/active_storage/blob.rb b/activestorage/app/models/active_storage/blob.rb
new file mode 100644
index 0000000000..3b48ee72af
--- /dev/null
+++ b/activestorage/app/models/active_storage/blob.rb
@@ -0,0 +1,328 @@
+# frozen_string_literal: true
+
+require "active_storage/analyzer/null_analyzer"
+
+# A blob is a record that contains the metadata about a file and a key for where that file resides on the service.
+# Blobs can be created in two ways:
+#
+# 1. Subsequent to the file being uploaded server-side to the service via <tt>create_after_upload!</tt>.
+# 2. Ahead of the file being directly uploaded client-side to the service via <tt>create_before_direct_upload!</tt>.
+#
+# The first option doesn't require any client-side JavaScript integration, and can be used by any other back-end
+# service that deals with files. The second option is faster, since you're not using your own server as a staging
+# point for uploads, and can work with deployments like Heroku that do not provide large amounts of disk space.
+#
+# Blobs are intended to be immutable in as-so-far as their reference to a specific file goes. You're allowed to
+# update a blob's metadata on a subsequent pass, but you should not update the key or change the uploaded file.
+# If you need to create a derivative or otherwise change the blob, simply create a new blob and purge the old one.
+class ActiveStorage::Blob < ActiveRecord::Base
+  class InvariableError < StandardError; end
+  class UnpreviewableError < StandardError; end
+  class UnrepresentableError < StandardError; end
+
+  self.table_name = "active_storage_blobs"
+
+  has_secure_token :key
+  store :metadata, accessors: [ :analyzed ], coder: JSON
+
+  class_attribute :service
+
+  has_many :attachments
+
+  has_one_attached :preview_image
+
+  class << self
+    # You can used the signed ID of a blob to refer to it on the client side without fear of tampering.
+    # This is particularly helpful for direct uploads where the client-side needs to refer to the blob
+    # that was created ahead of the upload itself on form submission.
+    #
+    # The signed ID is also used to create stable URLs for the blob through the BlobsController.
+    def find_signed(id)
+      find ActiveStorage.verifier.verify(id, purpose: :blob_id)
+    end
+
+    # Returns a new, unsaved blob instance after the +io+ has been uploaded to the service.
+    def build_after_upload(io:, filename:, content_type: nil, metadata: nil)
+      new.tap do |blob|
+        blob.filename     = filename
+        blob.content_type = content_type
+        blob.metadata     = metadata
+
+        blob.upload io
+      end
+    end
+
+    # Returns a saved blob instance after the +io+ has been uploaded to the service. Note, the blob is first built,
+    # then the +io+ is uploaded, then the blob is saved. This is done this way to avoid uploading (which may take
+    # time), while having an open database transaction.
+    def create_after_upload!(io:, filename:, content_type: nil, metadata: nil)
+      build_after_upload(io: io, filename: filename, content_type: content_type, metadata: metadata).tap(&:save!)
+    end
+
+    # Returns a saved blob _without_ uploading a file to the service. This blob will point to a key where there is
+    # no file yet. It's intended to be used together with a client-side upload, which will first create the blob
+    # in order to produce the signed URL for uploading. This signed URL points to the key generated by the blob.
+    # Once the form using the direct upload is submitted, the blob can be associated with the right record using
+    # the signed ID.
+    def create_before_direct_upload!(filename:, byte_size:, checksum:, content_type: nil, metadata: nil)
+      create! filename: filename, byte_size: byte_size, checksum: checksum, content_type: content_type, metadata: metadata
+    end
+  end
+
+
+  # Returns a signed ID for this blob that's suitable for reference on the client-side without fear of tampering.
+  # It uses the framework-wide verifier on <tt>ActiveStorage.verifier</tt>, but with a dedicated purpose.
+  def signed_id
+    ActiveStorage.verifier.generate(id, purpose: :blob_id)
+  end
+
+  # Returns the key pointing to the file on the service that's associated with this blob. The key is in the
+  # standard secure-token format from Rails. So it'll look like: XTAPjJCJiuDrLk3TmwyJGpUo. This key is not intended
+  # to be revealed directly to the user. Always refer to blobs using the signed_id or a verified form of the key.
+  def key
+    # We can't wait until the record is first saved to have a key for it
+    self[:key] ||= self.class.generate_unique_secure_token
+  end
+
+  # Returns an ActiveStorage::Filename instance of the filename that can be
+  # queried for basename, extension, and a sanitized version of the filename
+  # that's safe to use in URLs.
+  def filename
+    ActiveStorage::Filename.new(self[:filename])
+  end
+
+  # Returns true if the content_type of this blob is in the image range, like image/png.
+  def image?
+    content_type.start_with?("image")
+  end
+
+  # Returns true if the content_type of this blob is in the audio range, like audio/mpeg.
+  def audio?
+    content_type.start_with?("audio")
+  end
+
+  # Returns true if the content_type of this blob is in the video range, like video/mp4.
+  def video?
+    content_type.start_with?("video")
+  end
+
+  # Returns true if the content_type of this blob is in the text range, like text/plain.
+  def text?
+    content_type.start_with?("text")
+  end
+
+
+  # Returns an ActiveStorage::Variant instance with the set of +transformations+ provided. This is only relevant for image
+  # files, and it allows any image to be transformed for size, colors, and the like. Example:
+  #
+  #   avatar.variant(resize: "100x100").processed.service_url
+  #
+  # This will create and process a variant of the avatar blob that's constrained to a height and width of 100px.
+  # Then it'll upload said variant to the service according to a derivative key of the blob and the transformations.
+  #
+  # Frequently, though, you don't actually want to transform the variant right away. But rather simply refer to a
+  # specific variant that can be created by a controller on-demand. Like so:
+  #
+  #   <%= image_tag Current.user.avatar.variant(resize: "100x100") %>
+  #
+  # This will create a URL for that specific blob with that specific variant, which the ActiveStorage::VariantsController
+  # can then produce on-demand.
+  #
+  # Raises ActiveStorage::Blob::InvariableError if ImageMagick cannot transform the blob. To determine whether a blob is
+  # variable, call ActiveStorage::Blob#previewable?.
+  def variant(transformations)
+    if variable?
+      ActiveStorage::Variant.new(self, ActiveStorage::Variation.wrap(transformations))
+    else
+      raise InvariableError
+    end
+  end
+
+  # Returns true if ImageMagick can transform the blob (its content type is in +ActiveStorage.variable_content_types+).
+  def variable?
+    ActiveStorage.variable_content_types.include?(content_type)
+  end
+
+
+  # Returns an ActiveStorage::Preview instance with the set of +transformations+ provided. A preview is an image generated
+  # from a non-image blob. Active Storage comes with built-in previewers for videos and PDF documents. The video previewer
+  # extracts the first frame from a video and the PDF previewer extracts the first page from a PDF document.
+  #
+  #   blob.preview(resize: "100x100").processed.service_url
+  #
+  # Avoid processing previews synchronously in views. Instead, link to a controller action that processes them on demand.
+  # Active Storage provides one, but you may want to create your own (for example, if you need authentication). Here’s
+  # how to use the built-in version:
+  #
+  #   <%= image_tag video.preview(resize: "100x100") %>
+  #
+  # This method raises ActiveStorage::Blob::UnpreviewableError if no previewer accepts the receiving blob. To determine
+  # whether a blob is accepted by any previewer, call ActiveStorage::Blob#previewable?.
+  def preview(transformations)
+    if previewable?
+      ActiveStorage::Preview.new(self, ActiveStorage::Variation.wrap(transformations))
+    else
+      raise UnpreviewableError
+    end
+  end
+
+  # Returns true if any registered previewer accepts the blob. By default, this will return true for videos and PDF documents.
+  def previewable?
+    ActiveStorage.previewers.any? { |klass| klass.accept?(self) }
+  end
+
+
+  # Returns an ActiveStorage::Preview for a previewable blob or an ActiveStorage::Variant for a variable image blob.
+  #
+  #   blob.representation(resize: "100x100").processed.service_url
+  #
+  # Raises ActiveStorage::Blob::UnrepresentableError if the receiving blob is neither variable nor previewable. Call
+  # ActiveStorage::Blob#representable? to determine whether a blob is representable.
+  #
+  # See ActiveStorage::Blob#preview and ActiveStorage::Blob#variant for more information.
+  def representation(transformations)
+    case
+    when previewable?
+      preview transformations
+    when variable?
+      variant transformations
+    else
+      raise UnrepresentableError
+    end
+  end
+
+  # Returns true if the blob is variable or previewable.
+  def representable?
+    variable? || previewable?
+  end
+
+
+  # Returns the URL of the blob on the service. This URL is intended to be short-lived for security and not used directly
+  # with users. Instead, the +service_url+ should only be exposed as a redirect from a stable, possibly authenticated URL.
+  # Hiding the +service_url+ behind a redirect also gives you the power to change services without updating all URLs. And
+  # it allows permanent URLs that redirect to the +service_url+ to be cached in the view.
+  def service_url(expires_in: service.url_expires_in, disposition: "inline")
+    service.url key, expires_in: expires_in, disposition: disposition, filename: filename, content_type: content_type
+  end
+
+  # Returns a URL that can be used to directly upload a file for this blob on the service. This URL is intended to be
+  # short-lived for security and only generated on-demand by the client-side JavaScript responsible for doing the uploading.
+  def service_url_for_direct_upload(expires_in: service.url_expires_in)
+    service.url_for_direct_upload key, expires_in: expires_in, content_type: content_type, content_length: byte_size, checksum: checksum
+  end
+
+  # Returns a Hash of headers for +service_url_for_direct_upload+ requests.
+  def service_headers_for_direct_upload
+    service.headers_for_direct_upload key, filename: filename, content_type: content_type, content_length: byte_size, checksum: checksum
+  end
+
+  # Uploads the +io+ to the service on the +key+ for this blob. Blobs are intended to be immutable, so you shouldn't be
+  # using this method after a file has already been uploaded to fit with a blob. If you want to create a derivative blob,
+  # you should instead simply create a new blob based on the old one.
+  #
+  # Prior to uploading, we compute the checksum, which is sent to the service for transit integrity validation. If the
+  # checksum does not match what the service receives, an exception will be raised. We also measure the size of the +io+
+  # and store that in +byte_size+ on the blob record.
+  #
+  # Normally, you do not have to call this method directly at all. Use the factory class methods of +build_after_upload+
+  # and +create_after_upload!+.
+  def upload(io)
+    self.checksum  = compute_checksum_in_chunks(io)
+    self.byte_size = io.size
+
+    service.upload(key, io, checksum: checksum)
+  end
+
+  # Downloads the file associated with this blob. If no block is given, the entire file is read into memory and returned.
+  # That'll use a lot of RAM for very large files. If a block is given, then the download is streamed and yielded in chunks.
+  def download(&block)
+    service.download key, &block
+  end
+
+
+  # Extracts and stores metadata from the file associated with this blob using a relevant analyzer. Active Storage comes
+  # with built-in analyzers for images and videos. See ActiveStorage::Analyzer::ImageAnalyzer and
+  # ActiveStorage::Analyzer::VideoAnalyzer for information about the specific attributes they extract and the third-party
+  # libraries they require.
+  #
+  # To choose the analyzer for a blob, Active Storage calls +accept?+ on each registered analyzer in order. It uses the
+  # first analyzer for which +accept?+ returns true when given the blob. If no registered analyzer accepts the blob, no
+  # metadata is extracted from it.
+  #
+  # In a Rails application, add or remove analyzers by manipulating +Rails.application.config.active_storage.analyzers+
+  # in an initializer:
+  #
+  #   # Add a custom analyzer for Microsoft Office documents:
+  #   Rails.application.config.active_storage.analyzers.append DOCXAnalyzer
+  #
+  #   # Remove the built-in video analyzer:
+  #   Rails.application.config.active_storage.analyzers.delete ActiveStorage::Analyzer::VideoAnalyzer
+  #
+  # Outside of a Rails application, manipulate +ActiveStorage.analyzers+ instead.
+  #
+  # You won't ordinarily need to call this method from a Rails application. New blobs are automatically and asynchronously
+  # analyzed via #analyze_later when they're attached for the first time.
+  def analyze
+    update! metadata: metadata.merge(extract_metadata_via_analyzer)
+  end
+
+  # Enqueues an ActiveStorage::AnalyzeJob which calls #analyze.
+  #
+  # This method is automatically called for a blob when it's attached for the first time. You can call it to analyze a blob
+  # again (e.g. if you add a new analyzer or modify an existing one).
+  def analyze_later
+    ActiveStorage::AnalyzeJob.perform_later(self)
+  end
+
+  # Returns true if the blob has been analyzed.
+  def analyzed?
+    analyzed
+  end
+
+
+  # Deletes the file on the service that's associated with this blob. This should only be done if the blob is going to be
+  # deleted as well or you will essentially have a dead reference. It's recommended to use the +#purge+ and +#purge_later+
+  # methods in most circumstances.
+  def delete
+    service.delete(key)
+    service.delete_prefixed("variants/#{key}/") if image?
+  end
+
+  # Deletes the file on the service and then destroys the blob record. This is the recommended way to dispose of unwanted
+  # blobs. Note, though, that deleting the file off the service will initiate a HTTP connection to the service, which may
+  # be slow or prevented, so you should not use this method inside a transaction or in callbacks. Use +#purge_later+ instead.
+  def purge
+    delete
+    destroy
+  end
+
+  # Enqueues an ActiveStorage::PurgeJob job that'll call +purge+. This is the recommended way to purge blobs when the call
+  # needs to be made from a transaction, a callback, or any other real-time scenario.
+  def purge_later
+    ActiveStorage::PurgeJob.perform_later(self)
+  end
+
+  private
+    def compute_checksum_in_chunks(io)
+      Digest::MD5.new.tap do |checksum|
+        while chunk = io.read(5.megabytes)
+          checksum << chunk
+        end
+
+        io.rewind
+      end.base64digest
+    end
+
+
+    def extract_metadata_via_analyzer
+      analyzer.metadata.merge(analyzed: true)
+    end
+
+    def analyzer
+      analyzer_class.new(self)
+    end
+
+    def analyzer_class
+      ActiveStorage.analyzers.detect { |klass| klass.accept?(self) } || ActiveStorage::Analyzer::NullAnalyzer
+    end
+end
diff --git a/activestorage/app/models/active_storage/filename.rb b/activestorage/app/models/active_storage/filename.rb
new file mode 100644
index 0000000000..b9413dec95
--- /dev/null
+++ b/activestorage/app/models/active_storage/filename.rb
@@ -0,0 +1,73 @@
+# frozen_string_literal: true
+
+# Encapsulates a string representing a filename to provide convenient access to parts of it and sanitization.
+# A Filename instance is returned by ActiveStorage::Blob#filename, and is comparable so it can be used for sorting.
+class ActiveStorage::Filename
+  include Comparable
+
+  def initialize(filename)
+    @filename = filename
+  end
+
+  # Returns the part of the filename preceding any extension.
+  #
+  #   ActiveStorage::Filename.new("racecar.jpg").base # => "racecar"
+  #   ActiveStorage::Filename.new("racecar").base     # => "racecar"
+  #   ActiveStorage::Filename.new(".gitignore").base  # => ".gitignore"
+  def base
+    File.basename @filename, extension_with_delimiter
+  end
+
+  # Returns the extension of the filename (i.e. the substring following the last dot, excluding a dot at the
+  # beginning) with the dot that precedes it. If the filename has no extension, an empty string is returned.
+  #
+  #   ActiveStorage::Filename.new("racecar.jpg").extension_with_delimiter # => ".jpg"
+  #   ActiveStorage::Filename.new("racecar").extension_with_delimiter     # => ""
+  #   ActiveStorage::Filename.new(".gitignore").extension_with_delimiter  # => ""
+  def extension_with_delimiter
+    File.extname @filename
+  end
+
+  # Returns the extension of the filename (i.e. the substring following the last dot, excluding a dot at
+  # the beginning). If the filename has no extension, an empty string is returned.
+  #
+  #   ActiveStorage::Filename.new("racecar.jpg").extension_without_delimiter # => "jpg"
+  #   ActiveStorage::Filename.new("racecar").extension_without_delimiter     # => ""
+  #   ActiveStorage::Filename.new(".gitignore").extension_without_delimiter  # => ""
+  def extension_without_delimiter
+    extension_with_delimiter.from(1).to_s
+  end
+
+  alias_method :extension, :extension_without_delimiter
+
+  # Returns the sanitized filename.
+  #
+  #   ActiveStorage::Filename.new("foo:bar.jpg").sanitized # => "foo-bar.jpg"
+  #   ActiveStorage::Filename.new("foo/bar.jpg").sanitized # => "foo-bar.jpg"
+  #
+  # Characters considered unsafe for storage (e.g. \, $, and the RTL override character) are replaced with a dash.
+  def sanitized
+    @filename.encode(Encoding::UTF_8, invalid: :replace, undef: :replace, replace: "�").strip.tr("\u{202E}%$|:;/\t\r\n\\", "-")
+  end
+
+  def parameters #:nodoc:
+    Parameters.new self
+  end
+
+  # Returns the sanitized version of the filename.
+  def to_s
+    sanitized.to_s
+  end
+
+  def as_json(*)
+    to_s
+  end
+
+  def to_json
+    to_s
+  end
+
+  def <=>(other)
+    to_s.downcase <=> other.to_s.downcase
+  end
+end
diff --git a/activestorage/app/models/active_storage/filename/parameters.rb b/activestorage/app/models/active_storage/filename/parameters.rb
new file mode 100644
index 0000000000..fb9ea10e49
--- /dev/null
+++ b/activestorage/app/models/active_storage/filename/parameters.rb
@@ -0,0 +1,36 @@
+# frozen_string_literal: true
+
+class ActiveStorage::Filename::Parameters #:nodoc:
+  attr_reader :filename
+
+  def initialize(filename)
+    @filename = filename
+  end
+
+  def combined
+    "#{ascii}; #{utf8}"
+  end
+
+  TRADITIONAL_ESCAPED_CHAR = /[^ A-Za-z0-9!#$+.^_`|~-]/
+
+  def ascii
+    'filename="' + percent_escape(I18n.transliterate(filename.sanitized), TRADITIONAL_ESCAPED_CHAR) + '"'
+  end
+
+  RFC_5987_ESCAPED_CHAR = /[^A-Za-z0-9!#$&+.^_`|~-]/
+
+  def utf8
+    "filename*=UTF-8''" + percent_escape(filename.sanitized, RFC_5987_ESCAPED_CHAR)
+  end
+
+  def to_s
+    combined
+  end
+
+  private
+    def percent_escape(string, pattern)
+      string.gsub(pattern) do |char|
+        char.bytes.map { |byte| "%%%02X" % byte }.join
+      end
+    end
+end
diff --git a/activestorage/app/models/active_storage/preview.rb b/activestorage/app/models/active_storage/preview.rb
new file mode 100644
index 0000000000..be5053edae
--- /dev/null
+++ b/activestorage/app/models/active_storage/preview.rb
@@ -0,0 +1,90 @@
+# frozen_string_literal: true
+
+# Some non-image blobs can be previewed: that is, they can be presented as images. A video blob can be previewed by
+# extracting its first frame, and a PDF blob can be previewed by extracting its first page.
+#
+# A previewer extracts a preview image from a blob. Active Storage provides previewers for videos and PDFs:
+# ActiveStorage::Previewer::VideoPreviewer and ActiveStorage::Previewer::PDFPreviewer. Build custom previewers by
+# subclassing ActiveStorage::Previewer and implementing the requisite methods. Consult the ActiveStorage::Previewer
+# documentation for more details on what's required of previewers.
+#
+# To choose the previewer for a blob, Active Storage calls +accept?+ on each registered previewer in order. It uses the
+# first previewer for which +accept?+ returns true when given the blob. In a Rails application, add or remove previewers
+# by manipulating +Rails.application.config.active_storage.previewers+ in an initializer:
+#
+#   Rails.application.config.active_storage.previewers
+#   # => [ ActiveStorage::Previewer::PDFPreviewer, ActiveStorage::Previewer::VideoPreviewer ]
+#
+#   # Add a custom previewer for Microsoft Office documents:
+#   Rails.application.config.active_storage.previewers << DOCXPreviewer
+#   # => [ ActiveStorage::Previewer::PDFPreviewer, ActiveStorage::Previewer::VideoPreviewer, DOCXPreviewer ]
+#
+# Outside of a Rails application, modify +ActiveStorage.previewers+ instead.
+#
+# The built-in previewers rely on third-party system libraries:
+#
+# * {ffmpeg}[https://www.ffmpeg.org]
+# * {mupdf}[https://mupdf.com]
+#
+# These libraries are not provided by Rails. You must install them yourself to use the built-in previewers. Before you
+# install and use third-party software, make sure you understand the licensing implications of doing so.
+class ActiveStorage::Preview
+  class UnprocessedError < StandardError; end
+
+  attr_reader :blob, :variation
+
+  def initialize(blob, variation_or_variation_key)
+    @blob, @variation = blob, ActiveStorage::Variation.wrap(variation_or_variation_key)
+  end
+
+  # Processes the preview if it has not been processed yet. Returns the receiving Preview instance for convenience:
+  #
+  #   blob.preview(resize: "100x100").processed.service_url
+  #
+  # Processing a preview generates an image from its blob and attaches the preview image to the blob. Because the preview
+  # image is stored with the blob, it is only generated once.
+  def processed
+    process unless processed?
+    self
+  end
+
+  # Returns the blob's attached preview image.
+  def image
+    blob.preview_image
+  end
+
+  # Returns the URL of the preview's variant on the service. Raises ActiveStorage::Preview::UnprocessedError if the
+  # preview has not been processed yet.
+  #
+  # This method synchronously processes a variant of the preview image, so do not call it in views. Instead, generate
+  # a stable URL that redirects to the short-lived URL returned by this method.
+  def service_url(**options)
+    if processed?
+      variant.service_url(options)
+    else
+      raise UnprocessedError
+    end
+  end
+
+  private
+    def processed?
+      image.attached?
+    end
+
+    def process
+      previewer.preview { |attachable| image.attach(attachable) }
+    end
+
+    def variant
+      ActiveStorage::Variant.new(image, variation).processed
+    end
+
+
+    def previewer
+      previewer_class.new(blob)
+    end
+
+    def previewer_class
+      ActiveStorage.previewers.detect { |klass| klass.accept?(blob) }
+    end
+end
diff --git a/activestorage/app/models/active_storage/variant.rb b/activestorage/app/models/active_storage/variant.rb
new file mode 100644
index 0000000000..e08a2271ec
--- /dev/null
+++ b/activestorage/app/models/active_storage/variant.rb
@@ -0,0 +1,132 @@
+# frozen_string_literal: true
+
+require "active_storage/downloading"
+
+# Image blobs can have variants that are the result of a set of transformations applied to the original.
+# These variants are used to create thumbnails, fixed-size avatars, or any other derivative image from the
+# original.
+#
+# Variants rely on {MiniMagick}[https://github.com/minimagick/minimagick] for the actual transformations
+# of the file, so you must add <tt>gem "mini_magick"</tt> to your Gemfile if you wish to use variants.
+#
+# Note that to create a variant it's necessary to download the entire blob file from the service and load it
+# into memory. The larger the image, the more memory is used. Because of this process, you also want to be
+# considerate about when the variant is actually processed. You shouldn't be processing variants inline in a
+# template, for example. Delay the processing to an on-demand controller, like the one provided in
+# ActiveStorage::VariantsController.
+#
+# To refer to such a delayed on-demand variant, simply link to the variant through the resolved route provided
+# by Active Storage like so:
+#
+#   <%= image_tag Current.user.avatar.variant(resize: "100x100") %>
+#
+# This will create a URL for that specific blob with that specific variant, which the ActiveStorage::VariantsController
+# can then produce on-demand.
+#
+# When you do want to actually produce the variant needed, call +processed+. This will check that the variant
+# has already been processed and uploaded to the service, and, if so, just return that. Otherwise it will perform
+# the transformations, upload the variant to the service, and return itself again. Example:
+#
+#   avatar.variant(resize: "100x100").processed.service_url
+#
+# This will create and process a variant of the avatar blob that's constrained to a height and width of 100.
+# Then it'll upload said variant to the service according to a derivative key of the blob and the transformations.
+#
+# A list of all possible transformations is available at https://www.imagemagick.org/script/mogrify.php. You can
+# combine as many as you like freely:
+#
+#   avatar.variant(resize: "100x100", monochrome: true, flip: "-90")
+class ActiveStorage::Variant
+  include ActiveStorage::Downloading
+
+  WEB_IMAGE_CONTENT_TYPES = %w( image/png image/jpeg image/jpg image/gif )
+
+  attr_reader :blob, :variation
+  delegate :service, to: :blob
+
+  def initialize(blob, variation_or_variation_key)
+    @blob, @variation = blob, ActiveStorage::Variation.wrap(variation_or_variation_key)
+  end
+
+  # Returns the variant instance itself after it's been processed or an existing processing has been found on the service.
+  def processed
+    process unless processed?
+    self
+  end
+
+  # Returns a combination key of the blob and the variation that together identifies a specific variant.
+  def key
+    "variants/#{blob.key}/#{Digest::SHA256.hexdigest(variation.key)}"
+  end
+
+  # Returns the URL of the variant on the service. This URL is intended to be short-lived for security and not used directly
+  # with users. Instead, the +service_url+ should only be exposed as a redirect from a stable, possibly authenticated URL.
+  # Hiding the +service_url+ behind a redirect also gives you the power to change services without updating all URLs. And
+  # it allows permanent URLs that redirect to the +service_url+ to be cached in the view.
+  #
+  # Use <tt>url_for(variant)</tt> (or the implied form, like +link_to variant+ or +redirect_to variant+) to get the stable URL
+  # for a variant that points to the ActiveStorage::VariantsController, which in turn will use this +service_call+ method
+  # for its redirection.
+  def service_url(expires_in: service.url_expires_in, disposition: :inline)
+    service.url key, expires_in: expires_in, disposition: disposition, filename: filename, content_type: content_type
+  end
+
+  # Returns the receiving variant. Allows ActiveStorage::Variant and ActiveStorage::Preview instances to be used interchangeably.
+  def image
+    self
+  end
+
+  private
+    def processed?
+      service.exist?(key)
+    end
+
+    def process
+      open_image do |image|
+        transform image
+        format image
+        upload image
+      end
+    end
+
+
+    def filename
+      if WEB_IMAGE_CONTENT_TYPES.include?(blob.content_type)
+        blob.filename
+      else
+        ActiveStorage::Filename.new("#{blob.filename.base}.png")
+      end
+    end
+
+    def content_type
+      blob.content_type.presence_in(WEB_IMAGE_CONTENT_TYPES) || "image/png"
+    end
+
+
+    def open_image(&block)
+      image = download_image
+
+      begin
+        yield image
+      ensure
+        image.destroy!
+      end
+    end
+
+    def download_image
+      require "mini_magick"
+      MiniMagick::Image.create { |file| download_blob_to(file) }
+    end
+
+    def transform(image)
+      variation.transform(image)
+    end
+
+    def format(image)
+      image.format("PNG") unless WEB_IMAGE_CONTENT_TYPES.include?(blob.content_type)
+    end
+
+    def upload(image)
+      File.open(image.path, "r") { |file| service.upload(key, file) }
+    end
+end
diff --git a/activestorage/app/models/active_storage/variation.rb b/activestorage/app/models/active_storage/variation.rb
new file mode 100644
index 0000000000..0046e6870b
--- /dev/null
+++ b/activestorage/app/models/active_storage/variation.rb
@@ -0,0 +1,79 @@
+# frozen_string_literal: true
+
+# A set of transformations that can be applied to a blob to create a variant. This class is exposed via
+# the ActiveStorage::Blob#variant method and should rarely be used directly.
+#
+# In case you do need to use this directly, it's instantiated using a hash of transformations where
+# the key is the command and the value is the arguments. Example:
+#
+#   ActiveStorage::Variation.new(resize: "100x100", monochrome: true, trim: true, rotate: "-90")
+#
+# A list of all possible transformations is available at https://www.imagemagick.org/script/mogrify.php.
+class ActiveStorage::Variation
+  attr_reader :transformations
+
+  class << self
+    # Returns a Variation instance based on the given variator. If the variator is a Variation, it is
+    # returned unmodified. If it is a String, it is passed to ActiveStorage::Variation.decode. Otherwise,
+    # it is assumed to be a transformations Hash and is passed directly to the constructor.
+    def wrap(variator)
+      case variator
+      when self
+        variator
+      when String
+        decode variator
+      else
+        new variator
+      end
+    end
+
+    # Returns a Variation instance with the transformations that were encoded by +encode+.
+    def decode(key)
+      new ActiveStorage.verifier.verify(key, purpose: :variation)
+    end
+
+    # Returns a signed key for the +transformations+, which can be used to refer to a specific
+    # variation in a URL or combined key (like <tt>ActiveStorage::Variant#key</tt>).
+    def encode(transformations)
+      ActiveStorage.verifier.generate(transformations, purpose: :variation)
+    end
+  end
+
+  def initialize(transformations)
+    @transformations = transformations
+  end
+
+  # Accepts an open MiniMagick image instance, like what's returned by <tt>MiniMagick::Image.read(io)</tt>,
+  # and performs the +transformations+ against it. The transformed image instance is then returned.
+  def transform(image)
+    transformations.each do |name, argument_or_subtransformations|
+      image.mogrify do |command|
+        if name.to_s == "combine_options"
+          argument_or_subtransformations.each do |subtransformation_name, subtransformation_argument|
+            pass_transform_argument(command, subtransformation_name, subtransformation_argument)
+          end
+        else
+          pass_transform_argument(command, name, argument_or_subtransformations)
+        end
+      end
+    end
+  end
+
+  # Returns a signed key for all the +transformations+ that this variation was instantiated with.
+  def key
+    self.class.encode(transformations)
+  end
+
+  private
+    def pass_transform_argument(command, method, argument)
+      if eligible_argument?(argument)
+        command.public_send(method, argument)
+      else
+        command.public_send(method)
+      end
+    end
+
+    def eligible_argument?(argument)
+      argument.present? && argument != true
+    end
+end
diff --git a/activestorage/bin/test b/activestorage/bin/test
new file mode 100755
index 0000000000..c53377cc97
--- /dev/null
+++ b/activestorage/bin/test
@@ -0,0 +1,5 @@
+#!/usr/bin/env ruby
+# frozen_string_literal: true
+
+COMPONENT_ROOT = File.expand_path("..", __dir__)
+require_relative "../../tools/test"
diff --git a/activestorage/config/routes.rb b/activestorage/config/routes.rb
new file mode 100644
index 0000000000..3f4129d915
--- /dev/null
+++ b/activestorage/config/routes.rb
@@ -0,0 +1,43 @@
+# frozen_string_literal: true
+
+Rails.application.routes.draw do
+  get "/rails/active_storage/blobs/:signed_id/*filename" => "active_storage/blobs#show", as: :rails_service_blob
+
+  direct :rails_blob do |blob, options|
+    route_for(:rails_service_blob, blob.signed_id, blob.filename, options)
+  end
+
+  resolve("ActiveStorage::Blob")       { |blob, options| route_for(:rails_blob, blob, options) }
+  resolve("ActiveStorage::Attachment") { |attachment, options| route_for(:rails_blob, attachment.blob, options) }
+
+
+  get "/rails/active_storage/variants/:signed_blob_id/:variation_key/*filename" => "active_storage/variants#show", as: :rails_blob_variation
+
+  direct :rails_variant do |variant, options|
+    signed_blob_id = variant.blob.signed_id
+    variation_key  = variant.variation.key
+    filename       = variant.blob.filename
+
+    route_for(:rails_blob_variation, signed_blob_id, variation_key, filename, options)
+  end
+
+  resolve("ActiveStorage::Variant") { |variant, options| route_for(:rails_variant, variant, options) }
+
+
+  get "/rails/active_storage/previews/:signed_blob_id/:variation_key/*filename" => "active_storage/previews#show", as: :rails_blob_preview
+
+  direct :rails_preview do |preview, options|
+    signed_blob_id = preview.blob.signed_id
+    variation_key  = preview.variation.key
+    filename       = preview.blob.filename
+
+    route_for(:rails_blob_preview, signed_blob_id, variation_key, filename, options)
+  end
+
+  resolve("ActiveStorage::Preview") { |preview, options| route_for(:rails_preview, preview, options) }
+
+
+  get  "/rails/active_storage/disk/:encoded_key/*filename" => "active_storage/disk#show", as: :rails_disk_service
+  put  "/rails/active_storage/disk/:encoded_token" => "active_storage/disk#update", as: :update_rails_disk_service
+  post "/rails/active_storage/direct_uploads" => "active_storage/direct_uploads#create", as: :rails_direct_uploads
+end
diff --git a/activestorage/db/migrate/20170806125915_create_active_storage_tables.rb b/activestorage/db/migrate/20170806125915_create_active_storage_tables.rb
new file mode 100644
index 0000000000..9e31e3966a
--- /dev/null
+++ b/activestorage/db/migrate/20170806125915_create_active_storage_tables.rb
@@ -0,0 +1,25 @@
+class CreateActiveStorageTables < ActiveRecord::Migration[5.2]
+  def change
+    create_table :active_storage_blobs do |t|
+      t.string   :key,        null: false
+      t.string   :filename,   null: false
+      t.string   :content_type
+      t.text     :metadata
+      t.bigint   :byte_size,  null: false
+      t.string   :checksum,   null: false
+      t.datetime :created_at, null: false
+
+      t.index [ :key ], unique: true
+    end
+
+    create_table :active_storage_attachments do |t|
+      t.string     :name,     null: false
+      t.references :record,   null: false, polymorphic: true, index: false
+      t.references :blob,     null: false
+
+      t.datetime :created_at, null: false
+
+      t.index [ :record_type, :record_id, :name, :blob_id ], name: "index_active_storage_attachments_uniqueness", unique: true
+    end
+  end
+end
diff --git a/activestorage/lib/active_storage.rb b/activestorage/lib/active_storage.rb
new file mode 100644
index 0000000000..4e6c02f71b
--- /dev/null
+++ b/activestorage/lib/active_storage.rb
@@ -0,0 +1,45 @@
+# frozen_string_literal: true
+
+#--
+# Copyright (c) 2017-2018 David Heinemeier Hansson, Basecamp
+#
+# Permission is hereby granted, free of charge, to any person obtaining
+# a copy of this software and associated documentation files (the
+# "Software"), to deal in the Software without restriction, including
+# without limitation the rights to use, copy, modify, merge, publish,
+# distribute, sublicense, and/or sell copies of the Software, and to
+# permit persons to whom the Software is furnished to do so, subject to
+# the following conditions:
+#
+# The above copyright notice and this permission notice shall be
+# included in all copies or substantial portions of the Software.
+#
+# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+# EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+# MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+# NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
+# LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
+# OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+# WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+#++
+
+require "active_record"
+require "active_support"
+require "active_support/rails"
+require "active_storage/version"
+
+module ActiveStorage
+  extend ActiveSupport::Autoload
+
+  autoload :Attached
+  autoload :Service
+  autoload :Previewer
+  autoload :Analyzer
+
+  mattr_accessor :logger
+  mattr_accessor :verifier
+  mattr_accessor :queue
+  mattr_accessor :previewers, default: []
+  mattr_accessor :analyzers, default: []
+  mattr_accessor :variable_content_types, default: []
+end
diff --git a/activestorage/lib/active_storage/analyzer.rb b/activestorage/lib/active_storage/analyzer.rb
new file mode 100644
index 0000000000..7c4168c1a0
--- /dev/null
+++ b/activestorage/lib/active_storage/analyzer.rb
@@ -0,0 +1,33 @@
+# frozen_string_literal: true
+
+require "active_storage/downloading"
+
+module ActiveStorage
+  # This is an abstract base class for analyzers, which extract metadata from blobs. See
+  # ActiveStorage::Analyzer::ImageAnalyzer for an example of a concrete subclass.
+  class Analyzer
+    include Downloading
+
+    attr_reader :blob
+
+    # Implement this method in a concrete subclass. Have it return true when given a blob from which
+    # the analyzer can extract metadata.
+    def self.accept?(blob)
+      false
+    end
+
+    def initialize(blob)
+      @blob = blob
+    end
+
+    # Override this method in a concrete subclass. Have it return a Hash of metadata.
+    def metadata
+      raise NotImplementedError
+    end
+
+    private
+      def logger #:doc:
+        ActiveStorage.logger
+      end
+  end
+end
diff --git a/activestorage/lib/active_storage/analyzer/image_analyzer.rb b/activestorage/lib/active_storage/analyzer/image_analyzer.rb
new file mode 100644
index 0000000000..25e0251e6e
--- /dev/null
+++ b/activestorage/lib/active_storage/analyzer/image_analyzer.rb
@@ -0,0 +1,36 @@
+# frozen_string_literal: true
+
+module ActiveStorage
+  # Extracts width and height in pixels from an image blob.
+  #
+  # Example:
+  #
+  #   ActiveStorage::Analyzer::ImageAnalyzer.new(blob).metadata
+  #   # => { width: 4104, height: 2736 }
+  #
+  # This analyzer relies on the third-party {MiniMagick}[https://github.com/minimagick/minimagick] gem. MiniMagick requires
+  # the {ImageMagick}[http://www.imagemagick.org] system library. These libraries are not provided by Rails; you must
+  # install them yourself to use this analyzer.
+  class Analyzer::ImageAnalyzer < Analyzer
+    def self.accept?(blob)
+      blob.image?
+    end
+
+    def metadata
+      read_image do |image|
+        { width: image.width, height: image.height }
+      end
+    rescue LoadError
+      logger.info "Skipping image analysis because the mini_magick gem isn't installed"
+      {}
+    end
+
+    private
+      def read_image
+        download_blob_to_tempfile do |file|
+          require "mini_magick"
+          yield MiniMagick::Image.new(file.path)
+        end
+      end
+  end
+end
diff --git a/activestorage/lib/active_storage/analyzer/null_analyzer.rb b/activestorage/lib/active_storage/analyzer/null_analyzer.rb
new file mode 100644
index 0000000000..8ff7ce48e5
--- /dev/null
+++ b/activestorage/lib/active_storage/analyzer/null_analyzer.rb
@@ -0,0 +1,13 @@
+# frozen_string_literal: true
+
+module ActiveStorage
+  class Analyzer::NullAnalyzer < Analyzer # :nodoc:
+    def self.accept?(blob)
+      true
+    end
+
+    def metadata
+      {}
+    end
+  end
+end
diff --git a/activestorage/lib/active_storage/analyzer/video_analyzer.rb b/activestorage/lib/active_storage/analyzer/video_analyzer.rb
new file mode 100644
index 0000000000..1c144baa37
--- /dev/null
+++ b/activestorage/lib/active_storage/analyzer/video_analyzer.rb
@@ -0,0 +1,93 @@
+# frozen_string_literal: true
+
+require "active_support/core_ext/hash/compact"
+
+module ActiveStorage
+  # Extracts the following from a video blob:
+  #
+  # * Width (pixels)
+  # * Height (pixels)
+  # * Duration (seconds)
+  # * Angle (degrees)
+  # * Aspect ratio
+  #
+  # Example:
+  #
+  #   ActiveStorage::VideoAnalyzer.new(blob).metadata
+  #   # => { width: 640, height: 480, duration: 5.0, angle: 0, aspect_ratio: [4, 3] }
+  #
+  # This analyzer requires the {ffmpeg}[https://www.ffmpeg.org] system library, which is not provided by Rails. You must
+  # install ffmpeg yourself to use this analyzer.
+  class Analyzer::VideoAnalyzer < Analyzer
+    class_attribute :ffprobe_path, default: "ffprobe"
+
+    def self.accept?(blob)
+      blob.video?
+    end
+
+    def metadata
+      { width: width, height: height, duration: duration, angle: angle, aspect_ratio: aspect_ratio }.compact
+    end
+
+    private
+      def width
+        rotated? ? raw_height : raw_width
+      end
+
+      def height
+        rotated? ? raw_width : raw_height
+      end
+
+      def raw_width
+        Integer(video_stream["width"]) if video_stream["width"]
+      end
+
+      def raw_height
+        Integer(video_stream["height"]) if video_stream["height"]
+      end
+
+      def duration
+        Float(video_stream["duration"]) if video_stream["duration"]
+      end
+
+      def angle
+        Integer(tags["rotate"]) if tags["rotate"]
+      end
+
+      def aspect_ratio
+        if descriptor = video_stream["display_aspect_ratio"]
+          descriptor.split(":", 2).collect(&:to_i)
+        end
+      end
+
+      def rotated?
+        angle == 90 || angle == 270
+      end
+
+
+      def tags
+        @tags ||= video_stream["tags"] || {}
+      end
+
+      def video_stream
+        @video_stream ||= streams.detect { |stream| stream["codec_type"] == "video" } || {}
+      end
+
+      def streams
+        probe["streams"] || []
+      end
+
+      def probe
+        download_blob_to_tempfile { |file| probe_from(file) }
+      end
+
+      def probe_from(file)
+        IO.popen([ ffprobe_path, "-print_format", "json", "-show_streams", "-v", "error", file.path ]) do |output|
+          JSON.parse(output.read)
+        end
+      rescue Errno::ENOENT
+        logger.info "Skipping video analysis because ffmpeg isn't installed"
+        {}
+      end
+  end
+end
diff --git a/activestorage/lib/active_storage/attached.rb b/activestorage/lib/active_storage/attached.rb
new file mode 100644
index 0000000000..c08fd56652
--- /dev/null
+++ b/activestorage/lib/active_storage/attached.rb
@@ -0,0 +1,40 @@
+# frozen_string_literal: true
+
+require "action_dispatch"
+require "action_dispatch/http/upload"
+require "active_support/core_ext/module/delegation"
+
+module ActiveStorage
+  # Abstract base class for the concrete ActiveStorage::Attached::One and ActiveStorage::Attached::Many
+  # classes that both provide proxy access to the blob association for a record.
+  class Attached
+    attr_reader :name, :record, :dependent
+
+    def initialize(name, record, dependent:)
+      @name, @record, @dependent = name, record, dependent
+    end
+
+    private
+      def create_blob_from(attachable)
+        case attachable
+        when ActiveStorage::Blob
+          attachable
+        when ActionDispatch::Http::UploadedFile, Rack::Test::UploadedFile
+          ActiveStorage::Blob.create_after_upload! \
+            io: attachable.open,
+            filename: attachable.original_filename,
+            content_type: attachable.content_type
+        when Hash
+          ActiveStorage::Blob.create_after_upload!(attachable)
+        when String
+          ActiveStorage::Blob.find_signed(attachable)
+        else
+          nil
+        end
+      end
+  end
+end
+
+require "active_storage/attached/one"
+require "active_storage/attached/many"
+require "active_storage/attached/macros"
diff --git a/activestorage/lib/active_storage/attached/macros.rb b/activestorage/lib/active_storage/attached/macros.rb
new file mode 100644
index 0000000000..2b38a9b887
--- /dev/null
+++ b/activestorage/lib/active_storage/attached/macros.rb
@@ -0,0 +1,96 @@
+# frozen_string_literal: true
+
+module ActiveStorage
+  # Provides the class-level DSL for declaring that an Active Record model has attached blobs.
+  module Attached::Macros
+    # Specifies the relation between a single attachment and the model.
+    #
+    #   class User < ActiveRecord::Base
+    #     has_one_attached :avatar
+    #   end
+    #
+    # There is no column defined on the model side, Active Storage takes
+    # care of the mapping between your records and the attachment.
+    #
+    # To avoid N+1 queries, you can include the attached blobs in your query like so:
+    #
+    #   User.with_attached_avatar
+    #
+    # Under the covers, this relationship is implemented as a +has_one+ association to a
+    # ActiveStorage::Attachment record and a +has_one-through+ association to a
+    # ActiveStorage::Blob record. These associations are available as +avatar_attachment+
+    # and +avatar_blob+. But you shouldn't need to work with these associations directly in
+    # most circumstances.
+    #
+    # The system has been designed to having you go through the ActiveStorage::Attached::One
+    # proxy that provides the dynamic proxy to the associations and factory methods, like +attach+.
+    #
+    # If the +:dependent+ option isn't set, the attachment will be purged
+    # (i.e. destroyed) whenever the record is destroyed.
+    def has_one_attached(name, dependent: :purge_later)
+      class_eval <<-CODE, __FILE__, __LINE__ + 1
+        def #{name}
+          @active_storage_attached_#{name} ||= ActiveStorage::Attached::One.new("#{name}", self, dependent: #{dependent == :purge_later ? ":purge_later" : "false"})
+        end
+
+        def #{name}=(attachable)
+          #{name}.attach(attachable)
+        end
+      CODE
+
+      has_one :"#{name}_attachment", -> { where(name: name) }, class_name: "ActiveStorage::Attachment", as: :record
+      has_one :"#{name}_blob", through: :"#{name}_attachment", class_name: "ActiveStorage::Blob", source: :blob
+
+      scope :"with_attached_#{name}", -> { includes("#{name}_attachment": :blob) }
+
+      if dependent == :purge_later
+        before_destroy { public_send(name).purge_later }
+      end
+    end
+
+    # Specifies the relation between multiple attachments and the model.
+    #
+    #   class Gallery < ActiveRecord::Base
+    #     has_many_attached :photos
+    #   end
+    #
+    # There are no columns defined on the model side, Active Storage takes
+    # care of the mapping between your records and the attachments.
+    #
+    # To avoid N+1 queries, you can include the attached blobs in your query like so:
+    #
+    #   Gallery.where(user: Current.user).with_attached_photos
+    #
+    # Under the covers, this relationship is implemented as a +has_many+ association to a
+    # ActiveStorage::Attachment record and a +has_many-through+ association to a
+    # ActiveStorage::Blob record. These associations are available as +photos_attachments+
+    # and +photos_blobs+. But you shouldn't need to work with these associations directly in
+    # most circumstances.
+    #
+    # The system has been designed to having you go through the ActiveStorage::Attached::Many
+    # proxy that provides the dynamic proxy to the associations and factory methods, like +#attach+.
+    #
+    # If the +:dependent+ option isn't set, all the attachments will be purged
+    # (i.e. destroyed) whenever the record is destroyed.
+    def has_many_attached(name, dependent: :purge_later)
+      class_eval <<-CODE, __FILE__, __LINE__ + 1
+        def #{name}
+          @active_storage_attached_#{name} ||= ActiveStorage::Attached::Many.new("#{name}", self, dependent: #{dependent == :purge_later ? ":purge_later" : "false"})
+        end
+
+        def #{name}=(attachables)
+          #{name}.attach(attachables)
+        end
+      CODE
+
+      has_many :"#{name}_attachments", -> { where(name: name) }, as: :record, class_name: "ActiveStorage::Attachment"
+      has_many :"#{name}_blobs", through: :"#{name}_attachments", class_name: "ActiveStorage::Blob", source: :blob
+
+      scope :"with_attached_#{name}", -> { includes("#{name}_attachments": :blob) }
+
+      if dependent == :purge_later
+        before_destroy { public_send(name).purge_later }
+      end
+    end
+  end
+end
diff --git a/activestorage/lib/active_storage/attached/many.rb b/activestorage/lib/active_storage/attached/many.rb
new file mode 100644
index 0000000000..6eace65b79
--- /dev/null
+++ b/activestorage/lib/active_storage/attached/many.rb
@@ -0,0 +1,63 @@
+# frozen_string_literal: true
+
+module ActiveStorage
+  # Decorated proxy object representing of multiple attachments to a model.
+  class Attached::Many < Attached
+    delegate_missing_to :attachments
+
+    # Returns all the associated attachment records.
+    #
+    # All methods called on this proxy object that aren't listed here will automatically be delegated to +attachments+.
+    def attachments
+      record.public_send("#{name}_attachments")
+    end
+
+    # Associates one or several attachments with the current record, saving them to the database.
+    #
+    #   document.images.attach(params[:images]) # Array of ActionDispatch::Http::UploadedFile objects
+    #   document.images.attach(params[:signed_blob_id]) # Signed reference to blob from direct upload
+    #   document.images.attach(io: File.open("/path/to/racecar.jpg"), filename: "racecar.jpg", content_type: "image/jpg")
+    #   document.images.attach([ first_blob, second_blob ])
+    def attach(*attachables)
+      attachables.flatten.collect do |attachable|
+        if record.new_record?
+          attachments.build(record: record, blob: create_blob_from(attachable))
+        else
+          attachments.create!(record: record, blob: create_blob_from(attachable))
+        end
+      end
+    end
+
+    # Returns true if any attachments has been made.
+    #
+    #   class Gallery < ActiveRecord::Base
+    #     has_many_attached :photos
+    #   end
+    #
+    #   Gallery.new.photos.attached? # => false
+    def attached?
+      attachments.any?
+    end
+
+    # Deletes associated attachments without purging them, leaving their respective blobs in place.
+    def detach
+      attachments.destroy_all if attached?
+    end
+
+    # Directly purges each associated attachment (i.e. destroys the blobs and
+    # attachments and deletes the files on the service).
+    def purge
+      if attached?
+        attachments.each(&:purge)
+        attachments.reload
+      end
+    end
+
+    # Purges each associated attachment through the queuing system.
+    def purge_later
+      if attached?
+        attachments.each(&:purge_later)
+      end
+    end
+  end
+end
diff --git a/activestorage/lib/active_storage/attached/one.rb b/activestorage/lib/active_storage/attached/one.rb
new file mode 100644
index 0000000000..0244232b2c
--- /dev/null
+++ b/activestorage/lib/active_storage/attached/one.rb
@@ -0,0 +1,83 @@
+# frozen_string_literal: true
+
+module ActiveStorage
+  # Representation of a single attachment to a model.
+  class Attached::One < Attached
+    delegate_missing_to :attachment
+
+    # Returns the associated attachment record.
+    #
+    # You don't have to call this method to access the attachment's methods as
+    # they are all available at the model level.
+    def attachment
+      record.public_send("#{name}_attachment")
+    end
+
+    # Associates a given attachment with the current record, saving it to the database.
+    #
+    #   person.avatar.attach(params[:avatar]) # ActionDispatch::Http::UploadedFile object
+    #   person.avatar.attach(params[:signed_blob_id]) # Signed reference to blob from direct upload
+    #   person.avatar.attach(io: File.open("/path/to/face.jpg"), filename: "face.jpg", content_type: "image/jpg")
+    #   person.avatar.attach(avatar_blob) # ActiveStorage::Blob object
+    def attach(attachable)
+      if attached? && dependent == :purge_later
+        replace attachable
+      else
+        write_attachment build_attachment_from(attachable)
+      end
+    end
+
+    # Returns +true+ if an attachment has been made.
+    #
+    #   class User < ActiveRecord::Base
+    #     has_one_attached :avatar
+    #   end
+    #
+    #   User.new.avatar.attached? # => false
+    def attached?
+      attachment.present?
+    end
+
+    # Deletes the attachment without purging it, leaving its blob in place.
+    def detach
+      if attached?
+        attachment.destroy
+        write_attachment nil
+      end
+    end
+
+    # Directly purges the attachment (i.e. destroys the blob and
+    # attachment and deletes the file on the service).
+    def purge
+      if attached?
+        attachment.purge
+        write_attachment nil
+      end
+    end
+
+    # Purges the attachment through the queuing system.
+    def purge_later
+      if attached?
+        attachment.purge_later
+      end
+    end
+
+    private
+      def replace(attachable)
+        blob.tap do
+          transaction do
+            detach
+            write_attachment build_attachment_from(attachable)
+          end
+        end.purge_later
+      end
+
+      def build_attachment_from(attachable)
+        ActiveStorage::Attachment.new(record: record, name: name, blob: create_blob_from(attachable))
+      end
+
+      def write_attachment(attachment)
+        record.public_send("#{name}_attachment=", attachment)
+      end
+  end
+end
diff --git a/activestorage/lib/active_storage/downloading.rb b/activestorage/lib/active_storage/downloading.rb
new file mode 100644
index 0000000000..a57fda49b4
--- /dev/null
+++ b/activestorage/lib/active_storage/downloading.rb
@@ -0,0 +1,26 @@
+# frozen_string_literal: true
+
+module ActiveStorage
+  module Downloading
+    private
+      # Opens a new tempfile in #tempdir and copies blob data into it. Yields the tempfile.
+      def download_blob_to_tempfile # :doc:
+        Tempfile.open([ "ActiveStorage", blob.filename.extension_with_delimiter ], tempdir) do |file|
+          download_blob_to file
+          yield file
+        end
+      end
+
+      # Efficiently downloads blob data into the given file.
+      def download_blob_to(file) # :doc:
+        file.binmode
+        blob.download { |chunk| file.write(chunk) }
+        file.rewind
+      end
+
+      # Returns the directory in which tempfiles should be opened. Defaults to +Dir.tmpdir+.
+      def tempdir # :doc:
+        Dir.tmpdir
+      end
+  end
+end
diff --git a/activestorage/lib/active_storage/engine.rb b/activestorage/lib/active_storage/engine.rb
new file mode 100644
index 0000000000..b41d8bb4d7
--- /dev/null
+++ b/activestorage/lib/active_storage/engine.rb
@@ -0,0 +1,91 @@
+# frozen_string_literal: true
+
+require "rails"
+require "active_storage"
+
+require "active_storage/previewer/pdf_previewer"
+require "active_storage/previewer/video_previewer"
+
+require "active_storage/analyzer/image_analyzer"
+require "active_storage/analyzer/video_analyzer"
+
+module ActiveStorage
+  class Engine < Rails::Engine # :nodoc:
+    isolate_namespace ActiveStorage
+
+    config.active_storage = ActiveSupport::OrderedOptions.new
+    config.active_storage.previewers = [ ActiveStorage::Previewer::PDFPreviewer, ActiveStorage::Previewer::VideoPreviewer ]
+    config.active_storage.analyzers = [ ActiveStorage::Analyzer::ImageAnalyzer, ActiveStorage::Analyzer::VideoAnalyzer ]
+    config.active_storage.variable_content_types = [ "image/png", "image/gif", "image/jpg", "image/jpeg", "image/vnd.adobe.photoshop" ]
+    config.active_storage.paths = ActiveSupport::OrderedOptions.new
+
+    config.eager_load_namespaces << ActiveStorage
+
+    initializer "active_storage.configs" do
+      config.after_initialize do |app|
+        ActiveStorage.logger     = app.config.active_storage.logger || Rails.logger
+        ActiveStorage.queue      = app.config.active_storage.queue
+        ActiveStorage.previewers = app.config.active_storage.previewers || []
+        ActiveStorage.analyzers  = app.config.active_storage.analyzers || []
+        ActiveStorage.variable_content_types = app.config.active_storage.variable_content_types || []
+      end
+    end
+
+    initializer "active_storage.attached" do
+      require "active_storage/attached"
+
+      ActiveSupport.on_load(:active_record) do
+        extend ActiveStorage::Attached::Macros
+      end
+    end
+
+    initializer "active_storage.verifier" do
+      config.after_initialize do |app|
+        ActiveStorage.verifier = app.message_verifier("ActiveStorage")
+      end
+    end
+
+    initializer "active_storage.services" do
+      config.to_prepare do
+        if config_choice = Rails.configuration.active_storage.service
+          configs = Rails.configuration.active_storage.service_configurations ||= begin
+            config_file = Pathname.new(Rails.root.join("config/storage.yml"))
+            raise("Couldn't find Active Storage configuration in #{config_file}") unless config_file.exist?
+
+            require "yaml"
+            require "erb"
+
+            YAML.load(ERB.new(config_file.read).result) || {}
+          rescue Psych::SyntaxError => e
+            raise "YAML syntax error occurred while parsing #{config_file}. " \
+                  "Please note that YAML must be consistently indented using spaces. Tabs are not allowed. " \
+                  "Error: #{e.message}"
+          end
+
+          ActiveStorage::Blob.service =
+            begin
+              ActiveStorage::Service.configure config_choice, configs
+            rescue => e
+              raise e, "Cannot load `Rails.config.active_storage.service`:\n#{e.message}", e.backtrace
+            end
+        end
+      end
+    end
+
+    initializer "active_storage.paths" do
+      config.after_initialize do |app|
+        if ffprobe_path = app.config.active_storage.paths.ffprobe
+          ActiveStorage::Analyzer::VideoAnalyzer.ffprobe_path = ffprobe_path
+        end
+
+        if ffmpeg_path = app.config.active_storage.paths.ffmpeg
+          ActiveStorage::Previewer::VideoPreviewer.ffmpeg_path = ffmpeg_path
+        end
+
+        if mutool_path = app.config.active_storage.paths.mutool
+          ActiveStorage::Previewer::PDFPreviewer.mutool_path = mutool_path
+        end
+      end
+    end
+  end
+end
diff --git a/activestorage/lib/active_storage/gem_version.rb b/activestorage/lib/active_storage/gem_version.rb
new file mode 100644
index 0000000000..f048bb0b77
--- /dev/null
+++ b/activestorage/lib/active_storage/gem_version.rb
@@ -0,0 +1,17 @@
+# frozen_string_literal: true
+
+module ActiveStorage
+  # Returns the version of the currently loaded Active Storage as a <tt>Gem::Version</tt>.
+  def self.gem_version
+    Gem::Version.new VERSION::STRING
+  end
+
+  module VERSION
+    MAJOR = 5
+    MINOR = 2
+    TINY  = 0
+    PRE   = "beta2"
+
+    STRING = [MAJOR, MINOR, TINY, PRE].compact.join(".")
+  end
+end
diff --git a/activestorage/lib/active_storage/log_subscriber.rb b/activestorage/lib/active_storage/log_subscriber.rb
new file mode 100644
index 0000000000..a4e148c1a5
--- /dev/null
+++ b/activestorage/lib/active_storage/log_subscriber.rb
@@ -0,0 +1,56 @@
+# frozen_string_literal: true
+
+require "active_support/log_subscriber"
+
+module ActiveStorage
+  class LogSubscriber < ActiveSupport::LogSubscriber
+    def service_upload(event)
+      message = "Uploaded file to key: #{key_in(event)}"
+      message += " (checksum: #{event.payload[:checksum]})" if event.payload[:checksum]
+      info event, color(message, GREEN)
+    end
+
+    def service_download(event)
+      info event, color("Downloaded file from key: #{key_in(event)}", BLUE)
+    end
+
+    def service_delete(event)
+      info event, color("Deleted file from key: #{key_in(event)}", RED)
+    end
+
+    def service_delete_prefixed(event)
+      info event, color("Deleted files by key prefix: #{event.payload[:prefix]}", RED)
+    end
+
+    def service_exist(event)
+      debug event, color("Checked if file exists at key: #{key_in(event)} (#{event.payload[:exist] ? "yes" : "no"})", BLUE)
+    end
+
+    def service_url(event)
+      debug event, color("Generated URL for file at key: #{key_in(event)} (#{event.payload[:url]})", BLUE)
+    end
+
+    def logger
+      ActiveStorage.logger
+    end
+
+    private
+      def info(event, colored_message)
+        super log_prefix_for_service(event) + colored_message
+      end
+
+      def debug(event, colored_message)
+        super log_prefix_for_service(event) + colored_message
+      end
+
+      def log_prefix_for_service(event)
+        color "  #{event.payload[:service]} Storage (#{event.duration.round(1)}ms) ", CYAN
+      end
+
+      def key_in(event)
+        event.payload[:key]
+      end
+  end
+end
+
+ActiveStorage::LogSubscriber.attach_to :active_storage
diff --git a/activestorage/lib/active_storage/previewer.rb b/activestorage/lib/active_storage/previewer.rb
new file mode 100644
index 0000000000..7db9ae5956
--- /dev/null
+++ b/activestorage/lib/active_storage/previewer.rb
@@ -0,0 +1,62 @@
+# frozen_string_literal: true
+
+require "active_storage/downloading"
+
+module ActiveStorage
+  # This is an abstract base class for previewers, which generate images from blobs. See
+  # ActiveStorage::Previewer::PDFPreviewer and ActiveStorage::Previewer::VideoPreviewer for examples of
+  # concrete subclasses.
+  class Previewer
+    include Downloading
+
+    attr_reader :blob
+
+    # Implement this method in a concrete subclass. Have it return true when given a blob from which
+    # the previewer can generate an image.
+    def self.accept?(blob)
+      false
+    end
+
+    def initialize(blob)
+      @blob = blob
+    end
+
+    # Override this method in a concrete subclass. Have it yield an attachable preview image (i.e.
+    # anything accepted by ActiveStorage::Attached::One#attach).
+    def preview
+      raise NotImplementedError
+    end
+
+    private
+      # Executes a system command, capturing its binary output in a tempfile. Yields the tempfile.
+      #
+      # Use this method to shell out to a system library (e.g. mupdf or ffmpeg) for preview image
+      # generation. The resulting tempfile can be used as the +:io+ value in an attachable Hash:
+      #
+      #   def preview
+      #     download_blob_to_tempfile do |input|
+      #       draw "my-drawing-command", input.path, "--format", "png", "-" do |output|
+      #         yield io: output, filename: "#{blob.filename.base}.png", content_type: "image/png"
+      #       end
+      #     end
+      #   end
+      #
+      # The output tempfile is opened in the directory returned by ActiveStorage::Downloading#tempdir.
+      def draw(*argv) #:doc:
+        Tempfile.open("ActiveStorage", tempdir) do |file|
+          capture(*argv, to: file)
+          yield file
+        end
+      end
+
+      def capture(*argv, to:)
+        to.binmode
+        IO.popen(argv, err: File::NULL) { |out| IO.copy_stream(out, to) }
+        to.rewind
+      end
+
+      def logger #:doc:
+        ActiveStorage.logger
+      end
+  end
+end
diff --git a/activestorage/lib/active_storage/previewer/pdf_previewer.rb b/activestorage/lib/active_storage/previewer/pdf_previewer.rb
new file mode 100644
index 0000000000..b84aefcc9c
--- /dev/null
+++ b/activestorage/lib/active_storage/previewer/pdf_previewer.rb
@@ -0,0 +1,24 @@
+# frozen_string_literal: true
+
+module ActiveStorage
+  class Previewer::PDFPreviewer < Previewer
+    class_attribute :mutool_path, default: "mutool"
+
+    def self.accept?(blob)
+      blob.content_type == "application/pdf"
+    end
+
+    def preview
+      download_blob_to_tempfile do |input|
+        draw_first_page_from input do |output|
+          yield io: output, filename: "#{blob.filename.base}.png", content_type: "image/png"
+        end
+      end
+    end
+
+    private
+      def draw_first_page_from(file, &block)
+        draw mutool_path, "draw", "-F", "png", "-o", "-", file.path, "1", &block
+      end
+  end
+end
diff --git a/activestorage/lib/active_storage/previewer/video_previewer.rb b/activestorage/lib/active_storage/previewer/video_previewer.rb
new file mode 100644
index 0000000000..5d06e33f44
--- /dev/null
+++ b/activestorage/lib/active_storage/previewer/video_previewer.rb
@@ -0,0 +1,25 @@
+# frozen_string_literal: true
+
+module ActiveStorage
+  class Previewer::VideoPreviewer < Previewer
+    class_attribute :ffmpeg_path, default: "ffmpeg"
+
+    def self.accept?(blob)
+      blob.video?
+    end
+
+    def preview
+      download_blob_to_tempfile do |input|
+        draw_relevant_frame_from input do |output|
+          yield io: output, filename: "#{blob.filename.base}.png", content_type: "image/png"
+        end
+      end
+    end
+
+    private
+      def draw_relevant_frame_from(file, &block)
+        draw ffmpeg_path, "-i", file.path, "-y", "-vcodec", "png",
+          "-vf", "thumbnail", "-vframes", "1", "-f", "image2", "-", &block
+      end
+  end
+end
diff --git a/activestorage/lib/active_storage/service.rb b/activestorage/lib/active_storage/service.rb
new file mode 100644
index 0000000000..f2e1269f27
--- /dev/null
+++ b/activestorage/lib/active_storage/service.rb
@@ -0,0 +1,127 @@
+# frozen_string_literal: true
+
+require "active_storage/log_subscriber"
+
+module ActiveStorage
+  class IntegrityError < StandardError; end
+
+  # Abstract class serving as an interface for concrete services.
+  #
+  # The available services are:
+  #
+  # * +Disk+, to manage attachments saved directly on the hard drive.
+  # * +GCS+, to manage attachments through Google Cloud Storage.
+  # * +S3+, to manage attachments through Amazon S3.
+  # * +AzureStorage+, to manage attachments through Microsoft Azure Storage.
+  # * +Mirror+, to be able to use several services to manage attachments.
+  #
+  # Inside a Rails application, you can set-up your services through the
+  # generated <tt>config/storage.yml</tt> file and reference one
+  # of the aforementioned constant under the +service+ key. For example:
+  #
+  #   local:
+  #     service: Disk
+  #     root: <%= Rails.root.join("storage") %>
+  #
+  # You can checkout the service's constructor to know which keys are required.
+  #
+  # Then, in your application's configuration, you can specify the service to
+  # use like this:
+  #
+  #   config.active_storage.service = :local
+  #
+  # If you are using Active Storage outside of a Ruby on Rails application, you
+  # can configure the service to use like this:
+  #
+  #   ActiveStorage::Blob.service = ActiveStorage::Service.configure(
+  #     :Disk,
+  #     root: Pathname("/foo/bar/storage")
+  #   )
+  class Service
+    extend ActiveSupport::Autoload
+    autoload :Configurator
+
+    class_attribute :url_expires_in, default: 5.minutes
+
+    class << self
+      # Configure an Active Storage service by name from a set of configurations,
+      # typically loaded from a YAML file. The Active Storage engine uses this
+      # to set the global Active Storage service when the app boots.
+      def configure(service_name, configurations)
+        Configurator.build(service_name, configurations)
+      end
+
+      # Override in subclasses that stitch together multiple services and hence
+      # need to build additional services using the configurator.
+      #
+      # Passes the configurator and all of the service's config as keyword args.
+      #
+      # See MirrorService for an example.
+      def build(configurator:, service: nil, **service_config) #:nodoc:
+        new(**service_config)
+      end
+    end
+
+    # Upload the +io+ to the +key+ specified. If a +checksum+ is provided, the service will
+    # ensure a match when the upload has completed or raise an ActiveStorage::IntegrityError.
+    def upload(key, io, checksum: nil)
+      raise NotImplementedError
+    end
+
+    # Return the content of the file at the +key+.
+    def download(key)
+      raise NotImplementedError
+    end
+
+    # Delete the file at the +key+.
+    def delete(key)
+      raise NotImplementedError
+    end
+
+    # Delete files at keys starting with the +prefix+.
+    def delete_prefixed(prefix)
+      raise NotImplementedError
+    end
+
+    # Return +true+ if a file exists at the +key+.
+    def exist?(key)
+      raise NotImplementedError
+    end
+
+    # Returns a signed, temporary URL for the file at the +key+. The URL will be valid for the amount
+    # of seconds specified in +expires_in+. You most also provide the +disposition+ (+:inline+ or +:attachment+),
+    # +filename+, and +content_type+ that you wish the file to be served with on request.
+    def url(key, expires_in:, disposition:, filename:, content_type:)
+      raise NotImplementedError
+    end
+
+    # Returns a signed, temporary URL that a direct upload file can be PUT to on the +key+.
+    # The URL will be valid for the amount of seconds specified in +expires_in+.
+    # You must also provide the +content_type+, +content_length+, and +checksum+ of the file
+    # that will be uploaded. All these attributes will be validated by the service upon upload.
+    def url_for_direct_upload(key, expires_in:, content_type:, content_length:, checksum:)
+      raise NotImplementedError
+    end
+
+    # Returns a Hash of headers for +url_for_direct_upload+ requests.
+    def headers_for_direct_upload(key, filename:, content_type:, content_length:, checksum:)
+      {}
+    end
+
+    private
+      def instrument(operation, payload = {}, &block)
+        ActiveSupport::Notifications.instrument(
+          "service_#{operation}.active_storage",
+          payload.merge(service: service_name), &block)
+      end
+
+      def service_name
+        # ActiveStorage::Service::DiskService => Disk
+        self.class.name.split("::").third.remove("Service")
+      end
+
+      def content_disposition_with(type: "inline", filename:)
+        (type.to_s.presence_in(%w( attachment inline )) || "inline") + "; #{filename.parameters}"
+      end
+  end
+end
diff --git a/activestorage/lib/active_storage/service/azure_storage_service.rb b/activestorage/lib/active_storage/service/azure_storage_service.rb
new file mode 100644
index 0000000000..0a9eb7f23d
--- /dev/null
+++ b/activestorage/lib/active_storage/service/azure_storage_service.rb
@@ -0,0 +1,140 @@
+# frozen_string_literal: true
+
+require "active_support/core_ext/numeric/bytes"
+require "azure/storage"
+require "azure/storage/core/auth/shared_access_signature"
+
+module ActiveStorage
+  # Wraps the Microsoft Azure Storage Blob Service as an Active Storage service.
+  # See ActiveStorage::Service for the generic API documentation that applies to all services.
+  class Service::AzureStorageService < Service
+    attr_reader :client, :path, :blobs, :container, :signer
+
+    def initialize(path:, storage_account_name:, storage_access_key:, container:)
+      @client = Azure::Storage::Client.create(storage_account_name: storage_account_name, storage_access_key: storage_access_key)
+      @signer = Azure::Storage::Core::Auth::SharedAccessSignature.new(storage_account_name, storage_access_key)
+      @blobs = client.blob_client
+      @container = container
+      @path = path
+    end
+
+    def upload(key, io, checksum: nil)
+      instrument :upload, key: key, checksum: checksum do
+        begin
+          blobs.create_block_blob(container, key, io, content_md5: checksum)
+        rescue Azure::Core::Http::HTTPError
+          raise ActiveStorage::IntegrityError
+        end
+      end
+    end
+
+    def download(key, &block)
+      if block_given?
+        instrument :streaming_download, key: key do
+          stream(key, &block)
+        end
+      else
+        instrument :download, key: key do
+          _, io = blobs.get_blob(container, key)
+          io.force_encoding(Encoding::BINARY)
+        end
+      end
+    end
+
+    def delete(key)
+      instrument :delete, key: key do
+        begin
+          blobs.delete_blob(container, key)
+        rescue Azure::Core::Http::HTTPError
+          # Ignore files already deleted
+        end
+      end
+    end
+
+    def delete_prefixed(prefix)
+      instrument :delete_prefixed, prefix: prefix do
+        marker = nil
+
+        loop do
+          results = blobs.list_blobs(container, prefix: prefix, marker: marker)
+
+          results.each do |blob|
+            blobs.delete_blob(container, blob.name)
+          end
+
+          break unless marker = results.continuation_token.presence
+        end
+      end
+    end
+
+    def exist?(key)
+      instrument :exist, key: key do |payload|
+        answer = blob_for(key).present?
+        payload[:exist] = answer
+        answer
+      end
+    end
+
+    def url(key, expires_in:, filename:, disposition:, content_type:)
+      instrument :url, key: key do |payload|
+        base_url = url_for(key)
+        generated_url = signer.signed_uri(
+          URI(base_url), false,
+          permissions: "r",
+          expiry: format_expiry(expires_in),
+          content_disposition: content_disposition_with(type: disposition, filename: filename),
+          content_type: content_type
+        ).to_s
+
+        payload[:url] = generated_url
+
+        generated_url
+      end
+    end
+
+    def url_for_direct_upload(key, expires_in:, content_type:, content_length:, checksum:)
+      instrument :url, key: key do |payload|
+        base_url = url_for(key)
+        generated_url = signer.signed_uri(URI(base_url), false, permissions: "rw",
+          expiry: format_expiry(expires_in)).to_s
+
+        payload[:url] = generated_url
+
+        generated_url
+      end
+    end
+
+    def headers_for_direct_upload(key, content_type:, checksum:, **)
+      { "Content-Type" => content_type, "Content-MD5" => checksum, "x-ms-blob-type" => "BlockBlob" }
+    end
+
+    private
+      def url_for(key)
+        "#{path}/#{container}/#{key}"
+      end
+
+      def blob_for(key)
+        blobs.get_blob_properties(container, key)
+      rescue Azure::Core::Http::HTTPError
+        false
+      end
+
+      def format_expiry(expires_in)
+        expires_in ? Time.now.utc.advance(seconds: expires_in).iso8601 : nil
+      end
+
+      # Reads the object for the given key in chunks, yielding each to the block.
+      def stream(key)
+        blob = blob_for(key)
+
+        chunk_size = 5.megabytes
+        offset = 0
+
+        while offset < blob.properties[:content_length]
+          _, chunk = blobs.get_blob(container, key, start_range: offset, end_range: offset + chunk_size - 1)
+          yield chunk.force_encoding(Encoding::BINARY)
+          offset += chunk_size
+        end
+      end
+  end
+end
diff --git a/activestorage/lib/active_storage/service/configurator.rb b/activestorage/lib/active_storage/service/configurator.rb
new file mode 100644
index 0000000000..39951fd026
--- /dev/null
+++ b/activestorage/lib/active_storage/service/configurator.rb
@@ -0,0 +1,32 @@
+# frozen_string_literal: true
+
+module ActiveStorage
+  class Service::Configurator #:nodoc:
+    attr_reader :configurations
+
+    def self.build(service_name, configurations)
+      new(configurations).build(service_name)
+    end
+
+    def initialize(configurations)
+      @configurations = configurations.deep_symbolize_keys
+    end
+
+    def build(service_name)
+      config = config_for(service_name.to_sym)
+      resolve(config.fetch(:service)).build(**config, configurator: self)
+    end
+
+    private
+      def config_for(name)
+        configurations.fetch name do
+          raise "Missing configuration for the #{name.inspect} Active Storage service. Configurations available for #{configurations.keys.inspect}"
+        end
+      end
+
+      def resolve(class_name)
+        require "active_storage/service/#{class_name.to_s.underscore}_service"
+        ActiveStorage::Service.const_get(:"#{class_name}Service")
+      end
+  end
+end
diff --git a/activestorage/lib/active_storage/service/disk_service.rb b/activestorage/lib/active_storage/service/disk_service.rb
new file mode 100644
index 0000000000..a8728c5bc3
--- /dev/null
+++ b/activestorage/lib/active_storage/service/disk_service.rb
@@ -0,0 +1,137 @@
+# frozen_string_literal: true
+
+require "fileutils"
+require "pathname"
+require "digest/md5"
+require "active_support/core_ext/numeric/bytes"
+
+module ActiveStorage
+  # Wraps a local disk path as an Active Storage service. See ActiveStorage::Service for the generic API
+  # documentation that applies to all services.
+  class Service::DiskService < Service
+    attr_reader :root
+
+    def initialize(root:)
+      @root = root
+    end
+
+    def upload(key, io, checksum: nil)
+      instrument :upload, key: key, checksum: checksum do
+        IO.copy_stream(io, make_path_for(key))
+        ensure_integrity_of(key, checksum) if checksum
+      end
+    end
+
+    def download(key)
+      if block_given?
+        instrument :streaming_download, key: key do
+          File.open(path_for(key), "rb") do |file|
+            while data = file.read(64.kilobytes)
+              yield data
+            end
+          end
+        end
+      else
+        instrument :download, key: key do
+          File.binread path_for(key)
+        end
+      end
+    end
+
+    def delete(key)
+      instrument :delete, key: key do
+        begin
+          File.delete path_for(key)
+        rescue Errno::ENOENT
+          # Ignore files already deleted
+        end
+      end
+    end
+
+    def delete_prefixed(prefix)
+      instrument :delete_prefixed, prefix: prefix do
+        Dir.glob(path_for("#{prefix}*")).each do |path|
+          FileUtils.rm_rf(path)
+        end
+      end
+    end
+
+    def exist?(key)
+      instrument :exist, key: key do |payload|
+        answer = File.exist? path_for(key)
+        payload[:exist] = answer
+        answer
+      end
+    end
+
+    def url(key, expires_in:, filename:, disposition:, content_type:)
+      instrument :url, key: key do |payload|
+        verified_key_with_expiration = ActiveStorage.verifier.generate(key, expires_in: expires_in, purpose: :blob_key)
+
+        generated_url =
+          if defined?(Rails.application)
+            Rails.application.routes.url_helpers.rails_disk_service_path \
+              verified_key_with_expiration,
+              filename: filename, disposition: content_disposition_with(type: disposition, filename: filename), content_type: content_type
+          else
+            "/rails/active_storage/disk/#{verified_key_with_expiration}/#{filename}?content_type=#{content_type}" \
+              "&disposition=#{content_disposition_with(type: disposition, filename: filename)}"
+          end
+
+        payload[:url] = generated_url
+
+        generated_url
+      end
+    end
+
+    def url_for_direct_upload(key, expires_in:, content_type:, content_length:, checksum:)
+      instrument :url, key: key do |payload|
+        verified_token_with_expiration = ActiveStorage.verifier.generate(
+          {
+            key: key,
+            content_type: content_type,
+            content_length: content_length,
+            checksum: checksum
+          },
+          { expires_in: expires_in,
+          purpose: :blob_token }
+        )
+
+        generated_url =
+          if defined?(Rails.application)
+            Rails.application.routes.url_helpers.update_rails_disk_service_path verified_token_with_expiration
+          else
+            "/rails/active_storage/disk/#{verified_token_with_expiration}"
+          end
+
+        payload[:url] = generated_url
+
+        generated_url
+      end
+    end
+
+    def headers_for_direct_upload(key, content_type:, **)
+      { "Content-Type" => content_type }
+    end
+
+    private
+      def path_for(key)
+        File.join root, folder_for(key), key
+      end
+
+      def folder_for(key)
+        [ key[0..1], key[2..3] ].join("/")
+      end
+
+      def make_path_for(key)
+        path_for(key).tap { |path| FileUtils.mkdir_p File.dirname(path) }
+      end
+
+      def ensure_integrity_of(key, checksum)
+        unless Digest::MD5.file(path_for(key)).base64digest == checksum
+          delete key
+          raise ActiveStorage::IntegrityError
+        end
+      end
+  end
+end
diff --git a/activestorage/lib/active_storage/service/gcs_service.rb b/activestorage/lib/active_storage/service/gcs_service.rb
new file mode 100644
index 0000000000..6f6f4105fe
--- /dev/null
+++ b/activestorage/lib/active_storage/service/gcs_service.rb
@@ -0,0 +1,113 @@
+# frozen_string_literal: true
+
+gem "google-cloud-storage", "~> 1.8"
+
+require "google/cloud/storage"
+require "active_support/core_ext/object/to_query"
+
+module ActiveStorage
+  # Wraps the Google Cloud Storage as an Active Storage service. See ActiveStorage::Service for the generic API
+  # documentation that applies to all services.
+  class Service::GCSService < Service
+    def initialize(**config)
+      @config = config
+    end
+
+    def upload(key, io, checksum: nil)
+      instrument :upload, key: key, checksum: checksum do
+        begin
+          # The official GCS client library doesn't allow us to create a file with no Content-Type metadata.
+          # We need the file we create to have no Content-Type so we can control it via the response-content-type
+          # param in signed URLs. Workaround: let the GCS client create the file with an inferred
+          # Content-Type (usually "application/octet-stream") then clear it.
+          bucket.create_file(io, key, md5: checksum).update do |file|
+            file.content_type = nil
+          end
+        rescue Google::Cloud::InvalidArgumentError
+          raise ActiveStorage::IntegrityError
+        end
+      end
+    end
+
+    # FIXME: Download in chunks when given a block.
+    def download(key)
+      instrument :download, key: key do
+        io = file_for(key).download
+        io.rewind
+
+        if block_given?
+          yield io.read
+        else
+          io.read
+        end
+      end
+    end
+
+    def delete(key)
+      instrument :delete, key: key do
+        begin
+          file_for(key).delete
+        rescue Google::Cloud::NotFoundError
+          # Ignore files already deleted
+        end
+      end
+    end
+
+    def delete_prefixed(prefix)
+      instrument :delete_prefixed, prefix: prefix do
+        bucket.files(prefix: prefix).all(&:delete)
+      end
+    end
+
+    def exist?(key)
+      instrument :exist, key: key do |payload|
+        answer = file_for(key).exists?
+        payload[:exist] = answer
+        answer
+      end
+    end
+
+    def url(key, expires_in:, filename:, content_type:, disposition:)
+      instrument :url, key: key do |payload|
+        generated_url = file_for(key).signed_url expires: expires_in, query: {
+          "response-content-disposition" => content_disposition_with(type: disposition, filename: filename),
+          "response-content-type" => content_type
+        }
+
+        payload[:url] = generated_url
+
+        generated_url
+      end
+    end
+
+    def url_for_direct_upload(key, expires_in:, content_type:, content_length:, checksum:)
+      instrument :url, key: key do |payload|
+        generated_url = bucket.signed_url key, method: "PUT", expires: expires_in,
+          content_type: content_type, content_md5: checksum
+
+        payload[:url] = generated_url
+
+        generated_url
+      end
+    end
+
+    def headers_for_direct_upload(key, content_type:, checksum:, **)
+      { "Content-Type" => content_type, "Content-MD5" => checksum }
+    end
+
+    private
+      attr_reader :config
+
+      def file_for(key)
+        bucket.file(key, skip_lookup: true)
+      end
+
+      def bucket
+        @bucket ||= client.bucket(config.fetch(:bucket))
+      end
+
+      def client
+        @client ||= Google::Cloud::Storage.new(config.except(:bucket))
+      end
+  end
+end
diff --git a/activestorage/lib/active_storage/service/mirror_service.rb b/activestorage/lib/active_storage/service/mirror_service.rb
new file mode 100644
index 0000000000..7eca8ce7f4
--- /dev/null
+++ b/activestorage/lib/active_storage/service/mirror_service.rb
@@ -0,0 +1,55 @@
+# frozen_string_literal: true
+
+require "active_support/core_ext/module/delegation"
+
+module ActiveStorage
+  # Wraps a set of mirror services and provides a single ActiveStorage::Service object that will all
+  # have the files uploaded to them. A +primary+ service is designated to answer calls to +download+, +exists?+,
+  # and +url+.
+  class Service::MirrorService < Service
+    attr_reader :primary, :mirrors
+
+    delegate :download, :exist?, :url, to: :primary
+
+    # Stitch together from named services.
+    def self.build(primary:, mirrors:, configurator:, **options) #:nodoc:
+      new \
+        primary: configurator.build(primary),
+        mirrors: mirrors.collect { |name| configurator.build name }
+    end
+
+    def initialize(primary:, mirrors:)
+      @primary, @mirrors = primary, mirrors
+    end
+
+    # Upload the +io+ to the +key+ specified to all services. If a +checksum+ is provided, all services will
+    # ensure a match when the upload has completed or raise an ActiveStorage::IntegrityError.
+    def upload(key, io, checksum: nil)
+      each_service.collect do |service|
+        service.upload key, io.tap(&:rewind), checksum: checksum
+      end
+    end
+
+    # Delete the file at the +key+ on all services.
+    def delete(key)
+      perform_across_services :delete, key
+    end
+
+    # Delete files at keys starting with the +prefix+ on all services.
+    def delete_prefixed(prefix)
+      perform_across_services :delete_prefixed, prefix
+    end
+
+    private
+      def each_service(&block)
+        [ primary, *mirrors ].each(&block)
+      end
+
+      def perform_across_services(method, *args)
+        # FIXME: Convert to be threaded
+        each_service.collect do |service|
+          service.public_send method, *args
+        end
+      end
+  end
+end
diff --git a/activestorage/lib/active_storage/service/s3_service.rb b/activestorage/lib/active_storage/service/s3_service.rb
new file mode 100644
index 0000000000..c95672f338
--- /dev/null
+++ b/activestorage/lib/active_storage/service/s3_service.rb
@@ -0,0 +1,106 @@
+# frozen_string_literal: true
+
+require "aws-sdk-s3"
+require "active_support/core_ext/numeric/bytes"
+
+module ActiveStorage
+  # Wraps the Amazon Simple Storage Service (S3) as an Active Storage service.
+  # See ActiveStorage::Service for the generic API documentation that applies to all services.
+  class Service::S3Service < Service
+    attr_reader :client, :bucket, :upload_options
+
+    def initialize(access_key_id:, secret_access_key:, region:, bucket:, upload: {}, **options)
+      @client = Aws::S3::Resource.new(access_key_id: access_key_id, secret_access_key: secret_access_key, region: region, **options)
+      @bucket = @client.bucket(bucket)
+
+      @upload_options = upload
+    end
+
+    def upload(key, io, checksum: nil)
+      instrument :upload, key: key, checksum: checksum do
+        begin
+          object_for(key).put(upload_options.merge(body: io, content_md5: checksum))
+        rescue Aws::S3::Errors::BadDigest
+          raise ActiveStorage::IntegrityError
+        end
+      end
+    end
+
+    def download(key, &block)
+      if block_given?
+        instrument :streaming_download, key: key do
+          stream(key, &block)
+        end
+      else
+        instrument :download, key: key do
+          object_for(key).get.body.read.force_encoding(Encoding::BINARY)
+        end
+      end
+    end
+
+    def delete(key)
+      instrument :delete, key: key do
+        object_for(key).delete
+      end
+    end
+
+    def delete_prefixed(prefix)
+      instrument :delete_prefixed, prefix: prefix do
+        bucket.objects(prefix: prefix).batch_delete!
+      end
+    end
+
+    def exist?(key)
+      instrument :exist, key: key do |payload|
+        answer = object_for(key).exists?
+        payload[:exist] = answer
+        answer
+      end
+    end
+
+    def url(key, expires_in:, filename:, disposition:, content_type:)
+      instrument :url, key: key do |payload|
+        generated_url = object_for(key).presigned_url :get, expires_in: expires_in.to_i,
+          response_content_disposition: content_disposition_with(type: disposition, filename: filename),
+          response_content_type: content_type
+
+        payload[:url] = generated_url
+
+        generated_url
+      end
+    end
+
+    def url_for_direct_upload(key, expires_in:, content_type:, content_length:, checksum:)
+      instrument :url, key: key do |payload|
+        generated_url = object_for(key).presigned_url :put, expires_in: expires_in.to_i,
+          content_type: content_type, content_length: content_length, content_md5: checksum
+
+        payload[:url] = generated_url
+
+        generated_url
+      end
+    end
+
+    def headers_for_direct_upload(key, content_type:, checksum:, **)
+      { "Content-Type" => content_type, "Content-MD5" => checksum }
+    end
+
+    private
+      def object_for(key)
+        bucket.object(key)
+      end
+
+      # Reads the object for the given key in chunks, yielding each to the block.
+      def stream(key)
+        object = object_for(key)
+
+        chunk_size = 5.megabytes
+        offset = 0
+
+        while offset < object.content_length
+          yield object.get(range: "bytes=#{offset}-#{offset + chunk_size - 1}").body.read.force_encoding(Encoding::BINARY)
+          offset += chunk_size
+        end
+      end
+  end
+end
diff --git a/activestorage/lib/active_storage/version.rb b/activestorage/lib/active_storage/version.rb
new file mode 100644
index 0000000000..4b6631832b
--- /dev/null
+++ b/activestorage/lib/active_storage/version.rb
@@ -0,0 +1,10 @@
+# frozen_string_literal: true
+
+require_relative "gem_version"
+
+module ActiveStorage
+  # Returns the version of the currently loaded ActiveStorage as a <tt>Gem::Version</tt>
+  def self.version
+    gem_version
+  end
+end
diff --git a/activestorage/lib/tasks/activestorage.rake b/activestorage/lib/tasks/activestorage.rake
new file mode 100644
index 0000000000..296e91afa1
--- /dev/null
+++ b/activestorage/lib/tasks/activestorage.rake
@@ -0,0 +1,12 @@
+# frozen_string_literal: true
+
+namespace :active_storage do
+  desc "Copy over the migration needed to the application"
+  task install: :environment do
+    if Rake::Task.task_defined?("active_storage:install:migrations")
+      Rake::Task["active_storage:install:migrations"].invoke
+    else
+      Rake::Task["app:active_storage:install:migrations"].invoke
+    end
+  end
+end
diff --git a/activestorage/package.json b/activestorage/package.json
new file mode 100644
index 0000000000..621706000b
--- /dev/null
+++ b/activestorage/package.json
@@ -0,0 +1,33 @@
+{
+  "name": "activestorage",
+  "version": "5.2.0-beta2",
+  "description": "Attach cloud and local files in Rails applications",
+  "main": "app/assets/javascripts/activestorage.js",
+  "files": [
+    "app/assets/javascripts/*.js"
+  ],
+  "homepage": "http://rubyonrails.org/",
+  "repository": {
+    "type": "git",
+    "url": "git+https://github.com/rails/rails.git"
+  },
+  "bugs": {
+    "url": "https://github.com/rails/rails/issues"
+  },
+  "author": "Javan Makhmali <javan@javan.us>",
+  "license": "MIT",
+  "devDependencies": {
+    "babel-core": "^6.25.0",
+    "babel-loader": "^7.1.1",
+    "babel-preset-env": "^1.6.0",
+    "eslint": "^4.3.0",
+    "eslint-plugin-import": "^2.7.0",
+    "spark-md5": "^3.0.0",
+    "webpack": "^3.4.0"
+  },
+  "scripts": {
+    "prebuild": "yarn lint",
+    "build": "webpack -p",
+    "lint": "eslint app/javascript"
+  }
+}
diff --git a/activestorage/test/analyzer/image_analyzer_test.rb b/activestorage/test/analyzer/image_analyzer_test.rb
new file mode 100644
index 0000000000..0d9f24c5c1
--- /dev/null
+++ b/activestorage/test/analyzer/image_analyzer_test.rb
@@ -0,0 +1,24 @@
+# frozen_string_literal: true
+
+require "test_helper"
+require "database/setup"
+
+require "active_storage/analyzer/image_analyzer"
+
+class ActiveStorage::Analyzer::ImageAnalyzerTest < ActiveSupport::TestCase
+  test "analyzing a JPEG image" do
+    blob = create_file_blob(filename: "racecar.jpg", content_type: "image/jpeg")
+    metadata = blob.tap(&:analyze).metadata
+
+    assert_equal 4104, metadata[:width]
+    assert_equal 2736, metadata[:height]
+  end
+
+  test "analyzing an SVG image without an XML declaration" do
+    blob = create_file_blob(filename: "icon.svg", content_type: "image/svg+xml")
+    metadata = blob.tap(&:analyze).metadata
+
+    assert_equal 792, metadata[:width]
+    assert_equal 584, metadata[:height]
+  end
+end
diff --git a/activestorage/test/analyzer/video_analyzer_test.rb b/activestorage/test/analyzer/video_analyzer_test.rb
new file mode 100644
index 0000000000..b3b9c97fe4
--- /dev/null
+++ b/activestorage/test/analyzer/video_analyzer_test.rb
@@ -0,0 +1,35 @@
+# frozen_string_literal: true
+
+require "test_helper"
+require "database/setup"
+
+require "active_storage/analyzer/video_analyzer"
+
+class ActiveStorage::Analyzer::VideoAnalyzerTest < ActiveSupport::TestCase
+  test "analyzing a video" do
+    blob = create_file_blob(filename: "video.mp4", content_type: "video/mp4")
+    metadata = blob.tap(&:analyze).metadata
+
+    assert_equal 640, metadata[:width]
+    assert_equal 480, metadata[:height]
+    assert_equal [4, 3], metadata[:aspect_ratio]
+    assert_equal 5.166648, metadata[:duration]
+    assert_not_includes metadata, :angle
+  end
+
+  test "analyzing a rotated video" do
+    blob = create_file_blob(filename: "rotated_video.mp4", content_type: "video/mp4")
+    metadata = blob.tap(&:analyze).metadata
+
+    assert_equal 480, metadata[:width]
+    assert_equal 640, metadata[:height]
+    assert_equal [4, 3], metadata[:aspect_ratio]
+    assert_equal 5.227975, metadata[:duration]
+    assert_equal 90, metadata[:angle]
+  end
+
+  test "analyzing a video without a video stream" do
+    blob = create_file_blob(filename: "video_without_video_stream.mp4", content_type: "video/mp4")
+    assert_equal({ "analyzed" => true }, blob.tap(&:analyze).metadata)
+  end
+end
diff --git a/activestorage/test/controllers/blobs_controller_test.rb b/activestorage/test/controllers/blobs_controller_test.rb
new file mode 100644
index 0000000000..9c811df895
--- /dev/null
+++ b/activestorage/test/controllers/blobs_controller_test.rb
@@ -0,0 +1,22 @@
+# frozen_string_literal: true
+
+require "test_helper"
+require "database/setup"
+
+class ActiveStorage::BlobsControllerTest < ActionDispatch::IntegrationTest
+  setup do
+    @blob = create_file_blob filename: "racecar.jpg"
+  end
+
+  test "showing blob with invalid signed ID" do
+    get rails_service_blob_url("invalid", "racecar.jpg")
+    assert_response :not_found
+  end
+
+  test "showing blob utilizes browser caching" do
+    get rails_blob_url(@blob)
+
+    assert_redirected_to(/racecar\.jpg/)
+    assert_equal "max-age=300, private", @response.headers["Cache-Control"]
+  end
+end
diff --git a/activestorage/test/controllers/direct_uploads_controller_test.rb b/activestorage/test/controllers/direct_uploads_controller_test.rb
new file mode 100644
index 0000000000..888767086c
--- /dev/null
+++ b/activestorage/test/controllers/direct_uploads_controller_test.rb
@@ -0,0 +1,124 @@
+# frozen_string_literal: true
+
+require "test_helper"
+require "database/setup"
+
+if SERVICE_CONFIGURATIONS[:s3] && SERVICE_CONFIGURATIONS[:s3][:access_key_id].present?
+  class ActiveStorage::S3DirectUploadsControllerTest < ActionDispatch::IntegrationTest
+    setup do
+      @old_service = ActiveStorage::Blob.service
+      ActiveStorage::Blob.service = ActiveStorage::Service.configure(:s3, SERVICE_CONFIGURATIONS)
+    end
+
+    teardown do
+      ActiveStorage::Blob.service = @old_service
+    end
+
+    test "creating new direct upload" do
+      checksum = Digest::MD5.base64digest("Hello")
+
+      post rails_direct_uploads_url, params: { blob: {
+        filename: "hello.txt", byte_size: 6, checksum: checksum, content_type: "text/plain" } }
+
+      response.parsed_body.tap do |details|
+        assert_equal ActiveStorage::Blob.find(details["id"]), ActiveStorage::Blob.find_signed(details["signed_id"])
+        assert_equal "hello.txt", details["filename"]
+        assert_equal 6, details["byte_size"]
+        assert_equal checksum, details["checksum"]
+        assert_equal "text/plain", details["content_type"]
+        assert_match SERVICE_CONFIGURATIONS[:s3][:bucket], details["direct_upload"]["url"]
+        assert_match(/s3\.(\S+)?amazonaws\.com/, details["direct_upload"]["url"])
+        assert_equal({ "Content-Type" => "text/plain", "Content-MD5" => checksum }, details["direct_upload"]["headers"])
+      end
+    end
+  end
+else
+  puts "Skipping S3 Direct Upload tests because no S3 configuration was supplied"
+end
+
+if SERVICE_CONFIGURATIONS[:gcs]
+  class ActiveStorage::GCSDirectUploadsControllerTest < ActionDispatch::IntegrationTest
+    setup do
+      @config = SERVICE_CONFIGURATIONS[:gcs]
+
+      @old_service = ActiveStorage::Blob.service
+      ActiveStorage::Blob.service = ActiveStorage::Service.configure(:gcs, SERVICE_CONFIGURATIONS)
+    end
+
+    teardown do
+      ActiveStorage::Blob.service = @old_service
+    end
+
+    test "creating new direct upload" do
+      checksum = Digest::MD5.base64digest("Hello")
+
+      post rails_direct_uploads_url, params: { blob: {
+        filename: "hello.txt", byte_size: 6, checksum: checksum, content_type: "text/plain" } }
+
+      @response.parsed_body.tap do |details|
+        assert_equal ActiveStorage::Blob.find(details["id"]), ActiveStorage::Blob.find_signed(details["signed_id"])
+        assert_equal "hello.txt", details["filename"]
+        assert_equal 6, details["byte_size"]
+        assert_equal checksum, details["checksum"]
+        assert_equal "text/plain", details["content_type"]
+        assert_match %r{storage\.googleapis\.com/#{@config[:bucket]}}, details["direct_upload"]["url"]
+        assert_equal({ "Content-Type" => "text/plain", "Content-MD5" => checksum }, details["direct_upload"]["headers"])
+      end
+    end
+  end
+else
+  puts "Skipping GCS Direct Upload tests because no GCS configuration was supplied"
+end
+
+if SERVICE_CONFIGURATIONS[:azure]
+  class ActiveStorage::AzureStorageDirectUploadsControllerTest < ActionDispatch::IntegrationTest
+    setup do
+      @config = SERVICE_CONFIGURATIONS[:azure]
+
+      @old_service = ActiveStorage::Blob.service
+      ActiveStorage::Blob.service = ActiveStorage::Service.configure(:azure, SERVICE_CONFIGURATIONS)
+    end
+
+    teardown do
+      ActiveStorage::Blob.service = @old_service
+    end
+
+    test "creating new direct upload" do
+      checksum = Digest::MD5.base64digest("Hello")
+
+      post rails_direct_uploads_url, params: { blob: {
+        filename: "hello.txt", byte_size: 6, checksum: checksum, content_type: "text/plain" } }
+
+      @response.parsed_body.tap do |details|
+        assert_equal ActiveStorage::Blob.find(details["id"]), ActiveStorage::Blob.find_signed(details["signed_id"])
+        assert_equal "hello.txt", details["filename"]
+        assert_equal 6, details["byte_size"]
+        assert_equal checksum, details["checksum"]
+        assert_equal "text/plain", details["content_type"]
+        assert_match %r{#{@config[:storage_account_name]}\.blob\.core\.windows\.net/#{@config[:container]}}, details["direct_upload"]["url"]
+        assert_equal({ "Content-Type" => "text/plain", "Content-MD5" => checksum, "x-ms-blob-type" => "BlockBlob" }, details["direct_upload"]["headers"])
+      end
+    end
+  end
+else
+  puts "Skipping Azure Storage Direct Upload tests because no Azure Storage configuration was supplied"
+end
+
+class ActiveStorage::DiskDirectUploadsControllerTest < ActionDispatch::IntegrationTest
+  test "creating new direct upload" do
+    checksum = Digest::MD5.base64digest("Hello")
+
+    post rails_direct_uploads_url, params: { blob: {
+      filename: "hello.txt", byte_size: 6, checksum: checksum, content_type: "text/plain" } }
+
+    @response.parsed_body.tap do |details|
+      assert_equal ActiveStorage::Blob.find(details["id"]), ActiveStorage::Blob.find_signed(details["signed_id"])
+      assert_equal "hello.txt", details["filename"]
+      assert_equal 6, details["byte_size"]
+      assert_equal checksum, details["checksum"]
+      assert_equal "text/plain", details["content_type"]
+      assert_match(/rails\/active_storage\/disk/, details["direct_upload"]["url"])
+      assert_equal({ "Content-Type" => "text/plain" }, details["direct_upload"]["headers"])
+    end
+  end
+end
diff --git a/activestorage/test/controllers/disk_controller_test.rb b/activestorage/test/controllers/disk_controller_test.rb
new file mode 100644
index 0000000000..940dbf5918
--- /dev/null
+++ b/activestorage/test/controllers/disk_controller_test.rb
@@ -0,0 +1,59 @@
+# frozen_string_literal: true
+
+require "test_helper"
+require "database/setup"
+
+class ActiveStorage::DiskControllerTest < ActionDispatch::IntegrationTest
+  test "showing blob inline" do
+    blob = create_blob
+
+    get blob.service_url
+    assert_equal "inline; filename=\"hello.txt\"; filename*=UTF-8''hello.txt", @response.headers["Content-Disposition"]
+    assert_equal "text/plain", @response.headers["Content-Type"]
+  end
+
+  test "showing blob as attachment" do
+    blob = create_blob
+
+    get blob.service_url(disposition: :attachment)
+    assert_equal "attachment; filename=\"hello.txt\"; filename*=UTF-8''hello.txt", @response.headers["Content-Disposition"]
+    assert_equal "text/plain", @response.headers["Content-Type"]
+  end
+
+
+  test "directly uploading blob with integrity" do
+    data = "Something else entirely!"
+    blob = create_blob_before_direct_upload byte_size: data.size, checksum: Digest::MD5.base64digest(data)
+
+    put blob.service_url_for_direct_upload, params: data, headers: { "Content-Type" => "text/plain" }
+    assert_response :no_content
+    assert_equal data, blob.download
+  end
+
+  test "directly uploading blob without integrity" do
+    data = "Something else entirely!"
+    blob = create_blob_before_direct_upload byte_size: data.size, checksum: Digest::MD5.base64digest("bad data")
+
+    put blob.service_url_for_direct_upload, params: data
+    assert_response :unprocessable_entity
+    assert_not blob.service.exist?(blob.key)
+  end
+
+  test "directly uploading blob with mismatched content type" do
+    data = "Something else entirely!"
+    blob = create_blob_before_direct_upload byte_size: data.size, checksum: Digest::MD5.base64digest(data)
+
+    put blob.service_url_for_direct_upload, params: data, headers: { "Content-Type" => "application/octet-stream" }
+    assert_response :unprocessable_entity
+    assert_not blob.service.exist?(blob.key)
+  end
+
+  test "directly uploading blob with mismatched content length" do
+    data = "Something else entirely!"
+    blob = create_blob_before_direct_upload byte_size: data.size - 1, checksum: Digest::MD5.base64digest(data)
+
+    put blob.service_url_for_direct_upload, params: data, headers: { "Content-Type" => "text/plain" }
+    assert_response :unprocessable_entity
+    assert_not blob.service.exist?(blob.key)
+  end
+end
diff --git a/activestorage/test/controllers/previews_controller_test.rb b/activestorage/test/controllers/previews_controller_test.rb
new file mode 100644
index 0000000000..704a466160
--- /dev/null
+++ b/activestorage/test/controllers/previews_controller_test.rb
@@ -0,0 +1,33 @@
+# frozen_string_literal: true
+
+require "test_helper"
+require "database/setup"
+
+class ActiveStorage::PreviewsControllerTest < ActionDispatch::IntegrationTest
+  setup do
+    @blob = create_file_blob filename: "report.pdf", content_type: "application/pdf"
+  end
+
+  test "showing preview inline" do
+    get rails_blob_preview_url(
+      filename: @blob.filename,
+      signed_blob_id: @blob.signed_id,
+      variation_key: ActiveStorage::Variation.encode(resize: "100x100"))
+
+    assert @blob.preview_image.attached?
+    assert_redirected_to(/report\.png\?.*disposition=inline/)
+
+    image = read_image(@blob.preview_image.variant(resize: "100x100"))
+    assert_equal 77, image.width
+    assert_equal 100, image.height
+  end
+
+  test "showing preview with invalid signed blob ID" do
+    get rails_blob_preview_url(
+      filename: @blob.filename,
+      signed_blob_id: "invalid",
+      variation_key: ActiveStorage::Variation.encode(resize: "100x100"))
+
+    assert_response :not_found
+  end
+end
diff --git a/activestorage/test/controllers/variants_controller_test.rb b/activestorage/test/controllers/variants_controller_test.rb
new file mode 100644
index 0000000000..a0642f9bed
--- /dev/null
+++ b/activestorage/test/controllers/variants_controller_test.rb
@@ -0,0 +1,32 @@
+# frozen_string_literal: true
+
+require "test_helper"
+require "database/setup"
+
+class ActiveStorage::VariantsControllerTest < ActionDispatch::IntegrationTest
+  setup do
+    @blob = create_file_blob filename: "racecar.jpg"
+  end
+
+  test "showing variant inline" do
+    get rails_blob_variation_url(
+      filename: @blob.filename,
+      signed_blob_id: @blob.signed_id,
+      variation_key: ActiveStorage::Variation.encode(resize: "100x100"))
+
+    assert_redirected_to(/racecar\.jpg\?.*disposition=inline/)
+
+    image = read_image(@blob.variant(resize: "100x100"))
+    assert_equal 100, image.width
+    assert_equal 67, image.height
+  end
+
+  test "showing variant with invalid signed blob ID" do
+    get rails_blob_variation_url(
+      filename: @blob.filename,
+      signed_blob_id: "invalid",
+      variation_key: ActiveStorage::Variation.encode(resize: "100x100"))
+
+    assert_response :not_found
+  end
+end
diff --git a/activestorage/test/database/create_users_migration.rb b/activestorage/test/database/create_users_migration.rb
new file mode 100644
index 0000000000..fdba87cacf
--- /dev/null
+++ b/activestorage/test/database/create_users_migration.rb
@@ -0,0 +1,9 @@
+# frozen_string_literal: true
+
+class ActiveStorageCreateUsers < ActiveRecord::Migration[5.2]
+  def change
+    create_table :users do |t|
+      t.string :name
+    end
+  end
+end
diff --git a/activestorage/test/database/setup.rb b/activestorage/test/database/setup.rb
new file mode 100644
index 0000000000..705650a25d
--- /dev/null
+++ b/activestorage/test/database/setup.rb
@@ -0,0 +1,7 @@
+# frozen_string_literal: true
+
+require_relative "create_users_migration"
+
+ActiveRecord::Base.establish_connection(adapter: "sqlite3", database: ":memory:")
+ActiveRecord::Migrator.migrate File.expand_path("../../db/migrate", __dir__)
+ActiveStorageCreateUsers.migrate(:up)
diff --git a/activestorage/test/dummy/Rakefile b/activestorage/test/dummy/Rakefile
new file mode 100644
index 0000000000..c4f9523878
--- /dev/null
+++ b/activestorage/test/dummy/Rakefile
@@ -0,0 +1,5 @@
+# frozen_string_literal: true
+
+require_relative "config/application"
+
+Rails.application.load_tasks
diff --git a/activestorage/test/dummy/app/assets/config/manifest.js b/activestorage/test/dummy/app/assets/config/manifest.js
new file mode 100644
index 0000000000..a8adebe722
--- /dev/null
+++ b/activestorage/test/dummy/app/assets/config/manifest.js
@@ -0,0 +1,5 @@
+
+//= link_tree ../images
+//= link_directory ../javascripts .js
+//= link_directory ../stylesheets .css
+//= link active_storage_manifest.js
diff --git a/activestorage/test/dummy/app/assets/images/.keep b/activestorage/test/dummy/app/assets/images/.keep
new file mode 100644
index 0000000000..e69de29bb2
--- /dev/null
+++ b/activestorage/test/dummy/app/assets/images/.keep
diff --git a/railties/lib/rails/generators/rails/plugin/templates/rails/javascripts.js b/activestorage/test/dummy/app/assets/javascripts/application.js
index e54c6461cc..e54c6461cc 100644
--- a/railties/lib/rails/generators/rails/plugin/templates/rails/javascripts.js
+++ b/activestorage/test/dummy/app/assets/javascripts/application.js
diff --git a/railties/lib/rails/generators/rails/app/templates/app/assets/stylesheets/application.css b/activestorage/test/dummy/app/assets/stylesheets/application.css
index 0ebd7fe829..0ebd7fe829 100644
--- a/railties/lib/rails/generators/rails/app/templates/app/assets/stylesheets/application.css
+++ b/activestorage/test/dummy/app/assets/stylesheets/application.css
diff --git a/activestorage/test/dummy/app/controllers/application_controller.rb b/activestorage/test/dummy/app/controllers/application_controller.rb
new file mode 100644
index 0000000000..280cc28ce2
--- /dev/null
+++ b/activestorage/test/dummy/app/controllers/application_controller.rb
@@ -0,0 +1,5 @@
+# frozen_string_literal: true
+
+class ApplicationController < ActionController::Base
+  protect_from_forgery with: :exception
+end
diff --git a/activestorage/test/dummy/app/controllers/concerns/.keep b/activestorage/test/dummy/app/controllers/concerns/.keep
new file mode 100644
index 0000000000..e69de29bb2
--- /dev/null
+++ b/activestorage/test/dummy/app/controllers/concerns/.keep
diff --git a/activestorage/test/dummy/app/helpers/application_helper.rb b/activestorage/test/dummy/app/helpers/application_helper.rb
new file mode 100644
index 0000000000..15b06f0f67
--- /dev/null
+++ b/activestorage/test/dummy/app/helpers/application_helper.rb
@@ -0,0 +1,4 @@
+# frozen_string_literal: true
+
+module ApplicationHelper
+end
diff --git a/activestorage/test/dummy/app/jobs/application_job.rb b/activestorage/test/dummy/app/jobs/application_job.rb
new file mode 100644
index 0000000000..d92ffddcb5
--- /dev/null
+++ b/activestorage/test/dummy/app/jobs/application_job.rb
@@ -0,0 +1,4 @@
+# frozen_string_literal: true
+
+class ApplicationJob < ActiveJob::Base
+end
diff --git a/activestorage/test/dummy/app/models/application_record.rb b/activestorage/test/dummy/app/models/application_record.rb
new file mode 100644
index 0000000000..71fbba5b32
--- /dev/null
+++ b/activestorage/test/dummy/app/models/application_record.rb
@@ -0,0 +1,5 @@
+# frozen_string_literal: true
+
+class ApplicationRecord < ActiveRecord::Base
+  self.abstract_class = true
+end
diff --git a/activestorage/test/dummy/app/models/concerns/.keep b/activestorage/test/dummy/app/models/concerns/.keep
new file mode 100644
index 0000000000..e69de29bb2
--- /dev/null
+++ b/activestorage/test/dummy/app/models/concerns/.keep
diff --git a/activestorage/test/dummy/app/views/layouts/application.html.erb b/activestorage/test/dummy/app/views/layouts/application.html.erb
new file mode 100644
index 0000000000..a6eb0174b7
--- /dev/null
+++ b/activestorage/test/dummy/app/views/layouts/application.html.erb
@@ -0,0 +1,14 @@
+<!DOCTYPE html>
+<html>
+  <head>
+    <title>Dummy</title>
+    <%= csrf_meta_tags %>
+
+    <%= stylesheet_link_tag    'application', media: 'all' %>
+    <%= javascript_include_tag 'application' %>
+  </head>
+
+  <body>
+    <%= yield %>
+  </body>
+</html>
diff --git a/activestorage/test/dummy/bin/bundle b/activestorage/test/dummy/bin/bundle
new file mode 100755
index 0000000000..5015ba6f8b
--- /dev/null
+++ b/activestorage/test/dummy/bin/bundle
@@ -0,0 +1,5 @@
+#!/usr/bin/env ruby
+# frozen_string_literal: true
+
+ENV["BUNDLE_GEMFILE"] ||= File.expand_path("../Gemfile", __dir__)
+load Gem.bin_path("bundler", "bundle")
diff --git a/activestorage/test/dummy/bin/rails b/activestorage/test/dummy/bin/rails
new file mode 100755
index 0000000000..22f2d8deee
--- /dev/null
+++ b/activestorage/test/dummy/bin/rails
@@ -0,0 +1,6 @@
+#!/usr/bin/env ruby
+# frozen_string_literal: true
+
+APP_PATH = File.expand_path("../config/application", __dir__)
+require_relative "../config/boot"
+require "rails/commands"
diff --git a/activestorage/test/dummy/bin/rake b/activestorage/test/dummy/bin/rake
new file mode 100755
index 0000000000..e436ea54a1
--- /dev/null
+++ b/activestorage/test/dummy/bin/rake
@@ -0,0 +1,6 @@
+#!/usr/bin/env ruby
+# frozen_string_literal: true
+
+require_relative "../config/boot"
+require "rake"
+Rake.application.run
diff --git a/activestorage/test/dummy/bin/yarn b/activestorage/test/dummy/bin/yarn
new file mode 100755
index 0000000000..c9b7498378
--- /dev/null
+++ b/activestorage/test/dummy/bin/yarn
@@ -0,0 +1,13 @@
+#!/usr/bin/env ruby
+# frozen_string_literal: true
+
+VENDOR_PATH = File.expand_path("..", __dir__)
+Dir.chdir(VENDOR_PATH) do
+  begin
+    exec "yarnpkg #{ARGV.join(" ")}"
+  rescue Errno::ENOENT
+    $stderr.puts "Yarn executable was not detected in the system."
+    $stderr.puts "Download Yarn at https://yarnpkg.com/en/docs/install"
+    exit 1
+  end
+end
diff --git a/activestorage/test/dummy/config.ru b/activestorage/test/dummy/config.ru
new file mode 100644
index 0000000000..bff88d608a
--- /dev/null
+++ b/activestorage/test/dummy/config.ru
@@ -0,0 +1,7 @@
+# frozen_string_literal: true
+
+# This file is used by Rack-based servers to start the application.
+
+require_relative "config/environment"
+
+run Rails.application
diff --git a/activestorage/test/dummy/config/application.rb b/activestorage/test/dummy/config/application.rb
new file mode 100644
index 0000000000..bd14ac0b1a
--- /dev/null
+++ b/activestorage/test/dummy/config/application.rb
@@ -0,0 +1,22 @@
+# frozen_string_literal: true
+
+require_relative "boot"
+
+require "rails"
+require "active_model/railtie"
+require "active_job/railtie"
+require "active_record/railtie"
+require "action_controller/railtie"
+require "action_view/railtie"
+require "sprockets/railtie"
+require "active_storage/engine"
+
+Bundler.require(*Rails.groups)
+
+module Dummy
+  class Application < Rails::Application
+    config.load_defaults 5.2
+
+    config.active_storage.service = :local
+  end
+end
diff --git a/activestorage/test/dummy/config/boot.rb b/activestorage/test/dummy/config/boot.rb
new file mode 100644
index 0000000000..72516d9255
--- /dev/null
+++ b/activestorage/test/dummy/config/boot.rb
@@ -0,0 +1,11 @@
+# frozen_string_literal: true
+
+# Set up gems listed in the Gemfile.
+ENV["BUNDLE_GEMFILE"] ||= File.expand_path("../../../Gemfile", __dir__)
+
+require "bundler/setup" if File.exist?(ENV["BUNDLE_GEMFILE"])
+$LOAD_PATH.unshift File.expand_path("../../../lib", __dir__)
+
+if %w[s server c console].any? { |a| ARGV.include?(a) }
+  puts "=> Booting Rails"
+end
diff --git a/activestorage/test/dummy/config/database.yml b/activestorage/test/dummy/config/database.yml
new file mode 100644
index 0000000000..0d02f24980
--- /dev/null
+++ b/activestorage/test/dummy/config/database.yml
@@ -0,0 +1,25 @@
+# SQLite version 3.x
+#   gem install sqlite3
+#
+#   Ensure the SQLite 3 gem is defined in your Gemfile
+#   gem 'sqlite3'
+#
+default: &default
+  adapter: sqlite3
+  pool: <%= ENV.fetch("RAILS_MAX_THREADS") { 5 } %>
+  timeout: 5000
+
+development:
+  <<: *default
+  database: db/development.sqlite3
+
+# Warning: The database defined as "test" will be erased and
+# re-generated from your development database when you run "rake".
+# Do not set this db to the same as development or production.
+test:
+  <<: *default
+  database: db/test.sqlite3
+
+production:
+  <<: *default
+  database: db/production.sqlite3
diff --git a/activestorage/test/dummy/config/environment.rb b/activestorage/test/dummy/config/environment.rb
new file mode 100644
index 0000000000..7df99e89c6
--- /dev/null
+++ b/activestorage/test/dummy/config/environment.rb
@@ -0,0 +1,7 @@
+# frozen_string_literal: true
+
+# Load the Rails application.
+require_relative "application"
+
+# Initialize the Rails application.
+Rails.application.initialize!
diff --git a/activestorage/test/dummy/config/environments/development.rb b/activestorage/test/dummy/config/environments/development.rb
new file mode 100644
index 0000000000..47fc5bf25c
--- /dev/null
+++ b/activestorage/test/dummy/config/environments/development.rb
@@ -0,0 +1,51 @@
+# frozen_string_literal: true
+
+Rails.application.configure do
+  # Settings specified here will take precedence over those in config/application.rb.
+
+  # In the development environment your application's code is reloaded on
+  # every request. This slows down response time but is perfect for development
+  # since you don't have to restart the web server when you make code changes.
+  config.cache_classes = false
+
+  # Do not eager load code on boot.
+  config.eager_load = false
+
+  # Show full error reports.
+  config.consider_all_requests_local = true
+
+  # Enable/disable caching. By default caching is disabled.
+  if Rails.root.join("tmp/caching-dev.txt").exist?
+    config.action_controller.perform_caching = true
+
+    config.cache_store = :memory_store
+    config.public_file_server.headers = {
+      "Cache-Control" => "public, max-age=#{2.days.seconds.to_i}"
+    }
+  else
+    config.action_controller.perform_caching = false
+
+    config.cache_store = :null_store
+  end
+
+  # Print deprecation notices to the Rails logger.
+  config.active_support.deprecation = :log
+
+  # Raise an error on page load if there are pending migrations.
+  config.active_record.migration_error = :page_load
+
+  # Debug mode disables concatenation and preprocessing of assets.
+  # This option may cause significant delays in view rendering with a large
+  # number of complex assets.
+  config.assets.debug = true
+
+  # Suppress logger output for asset requests.
+  config.assets.quiet = true
+
+  # Raises error for missing translations
+  # config.action_view.raise_on_missing_translations = true
+
+  # Use an evented file watcher to asynchronously detect changes in source code,
+  # routes, locales, etc. This feature depends on the listen gem.
+  # config.file_watcher = ActiveSupport::EventedFileUpdateChecker
+end
diff --git a/activestorage/test/dummy/config/environments/production.rb b/activestorage/test/dummy/config/environments/production.rb
new file mode 100644
index 0000000000..34ac3bc561
--- /dev/null
+++ b/activestorage/test/dummy/config/environments/production.rb
@@ -0,0 +1,84 @@
+# frozen_string_literal: true
+
+Rails.application.configure do
+  # Settings specified here will take precedence over those in config/application.rb.
+
+  # Code is not reloaded between requests.
+  config.cache_classes = true
+
+  # Eager load code on boot. This eager loads most of Rails and
+  # your application in memory, allowing both threaded web servers
+  # and those relying on copy on write to perform better.
+  # Rake tasks automatically ignore this option for performance.
+  config.eager_load = true
+
+  # Full error reports are disabled and caching is turned on.
+  config.consider_all_requests_local       = false
+  config.action_controller.perform_caching = true
+
+  # Attempt to read encrypted secrets from `config/secrets.yml.enc`.
+  # Requires an encryption key in `ENV["RAILS_MASTER_KEY"]` or
+  # `config/secrets.yml.key`.
+  config.read_encrypted_secrets = true
+
+  # Disable serving static files from the `/public` folder by default since
+  # Apache or NGINX already handles this.
+  config.public_file_server.enabled = ENV["RAILS_SERVE_STATIC_FILES"].present?
+
+  # Compress JavaScripts and CSS.
+  config.assets.js_compressor = :uglifier
+  # config.assets.css_compressor = :sass
+
+  # Do not fallback to assets pipeline if a precompiled asset is missed.
+  config.assets.compile = false
+
+  # `config.assets.precompile` and `config.assets.version` have moved to config/initializers/assets.rb
+
+  # Enable serving of images, stylesheets, and JavaScripts from an asset server.
+  # config.action_controller.asset_host = 'http://assets.example.com'
+
+  # Specifies the header that your server uses for sending files.
+  # config.action_dispatch.x_sendfile_header = 'X-Sendfile' # for Apache
+  # config.action_dispatch.x_sendfile_header = 'X-Accel-Redirect' # for NGINX
+
+  # Mount Action Cable outside main process or domain
+  # config.action_cable.mount_path = nil
+  # config.action_cable.url = 'wss://example.com/cable'
+  # config.action_cable.allowed_request_origins = [ 'http://example.com', /http:\/\/example.*/ ]
+
+  # Force all access to the app over SSL, use Strict-Transport-Security, and use secure cookies.
+  # config.force_ssl = true
+
+  # Use the lowest log level to ensure availability of diagnostic information
+  # when problems arise.
+  config.log_level = :debug
+
+  # Prepend all log lines with the following tags.
+  config.log_tags = [ :request_id ]
+
+  # Use a different cache store in production.
+  # config.cache_store = :mem_cache_store
+
+  # Enable locale fallbacks for I18n (makes lookups for any locale fall back to
+  # the I18n.default_locale when a translation cannot be found).
+  config.i18n.fallbacks = true
+
+  # Send deprecation notices to registered listeners.
+  config.active_support.deprecation = :notify
+
+  # Use default logging formatter so that PID and timestamp are not suppressed.
+  config.log_formatter = ::Logger::Formatter.new
+
+  # Use a different logger for distributed setups.
+  # require 'syslog/logger'
+  # config.logger = ActiveSupport::TaggedLogging.new(Syslog::Logger.new 'app-name')
+
+  if ENV["RAILS_LOG_TO_STDOUT"].present?
+    logger           = ActiveSupport::Logger.new(STDOUT)
+    logger.formatter = config.log_formatter
+    config.logger    = ActiveSupport::TaggedLogging.new(logger)
+  end
+
+  # Do not dump schema after migrations.
+  config.active_record.dump_schema_after_migration = false
+end
diff --git a/activestorage/test/dummy/config/environments/test.rb b/activestorage/test/dummy/config/environments/test.rb
new file mode 100644
index 0000000000..74a802d98c
--- /dev/null
+++ b/activestorage/test/dummy/config/environments/test.rb
@@ -0,0 +1,38 @@
+# frozen_string_literal: true
+
+Rails.application.configure do
+  # Settings specified here will take precedence over those in config/application.rb.
+
+  # The test environment is used exclusively to run your application's
+  # test suite. You never need to work with it otherwise. Remember that
+  # your test database is "scratch space" for the test suite and is wiped
+  # and recreated between test runs. Don't rely on the data there!
+  config.cache_classes = true
+
+  # Do not eager load code on boot. This avoids loading your whole application
+  # just for the purpose of running a single test. If you are using a tool that
+  # preloads Rails for running tests, you may have to set it to true.
+  config.eager_load = false
+
+  # Configure public file server for tests with Cache-Control for performance.
+  config.public_file_server.enabled = true
+  config.public_file_server.headers = {
+    "Cache-Control" => "public, max-age=#{1.hour.seconds.to_i}"
+  }
+
+  # Show full error reports and disable caching.
+  config.consider_all_requests_local       = true
+  config.action_controller.perform_caching = false
+
+  # Raise exceptions instead of rendering exception templates.
+  config.action_dispatch.show_exceptions = false
+
+  # Print deprecation notices to the stderr.
+  config.active_support.deprecation = :stderr
+
+  # Disable request forgery protection in test environment.
+  config.action_controller.allow_forgery_protection = false
+
+  # Raises error for missing translations
+  # config.action_view.raise_on_missing_translations = true
+end
diff --git a/railties/lib/rails/generators/rails/app/templates/config/initializers/application_controller_renderer.rb b/activestorage/test/dummy/config/initializers/application_controller_renderer.rb
index 51639b67a0..315ac48a9a 100644
--- a/railties/lib/rails/generators/rails/app/templates/config/initializers/application_controller_renderer.rb
+++ b/activestorage/test/dummy/config/initializers/application_controller_renderer.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 # Be sure to restart your server when you modify this file.
 
 # ApplicationController.renderer.defaults.merge!(
diff --git a/activestorage/test/dummy/config/initializers/assets.rb b/activestorage/test/dummy/config/initializers/assets.rb
new file mode 100644
index 0000000000..ba194685a2
--- /dev/null
+++ b/activestorage/test/dummy/config/initializers/assets.rb
@@ -0,0 +1,16 @@
+# frozen_string_literal: true
+
+# Be sure to restart your server when you modify this file.
+
+# Version of your assets, change this if you want to expire all your assets.
+Rails.application.config.assets.version = "1.0"
+
+# Add additional assets to the asset load path.
+# Rails.application.config.assets.paths << Emoji.images_path
+# Add Yarn node_modules folder to the asset load path.
+Rails.application.config.assets.paths << Rails.root.join("node_modules")
+
+# Precompile additional assets.
+# application.js, application.css, and all non-JS/CSS in the app/assets
+# folder are already added.
+# Rails.application.config.assets.precompile += %w( admin.js admin.css )
diff --git a/activestorage/test/dummy/config/initializers/backtrace_silencers.rb b/activestorage/test/dummy/config/initializers/backtrace_silencers.rb
new file mode 100644
index 0000000000..d0f0d3b5df
--- /dev/null
+++ b/activestorage/test/dummy/config/initializers/backtrace_silencers.rb
@@ -0,0 +1,8 @@
+# frozen_string_literal: true
+# Be sure to restart your server when you modify this file.
+
+# You can add backtrace silencers for libraries that you're using but don't wish to see in your backtraces.
+# Rails.backtrace_cleaner.add_silencer { |line| line =~ /my_noisy_library/ }
+
+# You can also remove all the silencers if you're trying to debug a problem that might stem from framework code.
+# Rails.backtrace_cleaner.remove_silencers!
diff --git a/activestorage/test/dummy/config/initializers/cookies_serializer.rb b/activestorage/test/dummy/config/initializers/cookies_serializer.rb
new file mode 100644
index 0000000000..ee8dff9c99
--- /dev/null
+++ b/activestorage/test/dummy/config/initializers/cookies_serializer.rb
@@ -0,0 +1,7 @@
+# frozen_string_literal: true
+
+# Be sure to restart your server when you modify this file.
+
+# Specify a serializer for the signed and encrypted cookie jars.
+# Valid options are :json, :marshal, and :hybrid.
+Rails.application.config.action_dispatch.cookies_serializer = :json
diff --git a/activestorage/test/dummy/config/initializers/filter_parameter_logging.rb b/activestorage/test/dummy/config/initializers/filter_parameter_logging.rb
new file mode 100644
index 0000000000..7a4f47b4c2
--- /dev/null
+++ b/activestorage/test/dummy/config/initializers/filter_parameter_logging.rb
@@ -0,0 +1,6 @@
+# frozen_string_literal: true
+
+# Be sure to restart your server when you modify this file.
+
+# Configure sensitive parameters which will be filtered from the log file.
+Rails.application.config.filter_parameters += [:password]
diff --git a/activestorage/test/dummy/config/initializers/inflections.rb b/activestorage/test/dummy/config/initializers/inflections.rb
new file mode 100644
index 0000000000..aa7435fbc9
--- /dev/null
+++ b/activestorage/test/dummy/config/initializers/inflections.rb
@@ -0,0 +1,17 @@
+# frozen_string_literal: true
+# Be sure to restart your server when you modify this file.
+
+# Add new inflection rules using the following format. Inflections
+# are locale specific, and you may define rules for as many different
+# locales as you wish. All of these examples are active by default:
+# ActiveSupport::Inflector.inflections(:en) do |inflect|
+#   inflect.plural /^(ox)$/i, '\1en'
+#   inflect.singular /^(ox)en/i, '\1'
+#   inflect.irregular 'person', 'people'
+#   inflect.uncountable %w( fish sheep )
+# end
+
+# These inflection rules are supported but not enabled by default:
+# ActiveSupport::Inflector.inflections(:en) do |inflect|
+#   inflect.acronym 'RESTful'
+# end
diff --git a/activestorage/test/dummy/config/initializers/mime_types.rb b/activestorage/test/dummy/config/initializers/mime_types.rb
new file mode 100644
index 0000000000..6e1d16f027
--- /dev/null
+++ b/activestorage/test/dummy/config/initializers/mime_types.rb
@@ -0,0 +1,5 @@
+# frozen_string_literal: true
+# Be sure to restart your server when you modify this file.
+
+# Add new mime types for use in respond_to blocks:
+# Mime::Type.register "text/richtext", :rtf
diff --git a/activestorage/test/dummy/config/initializers/wrap_parameters.rb b/activestorage/test/dummy/config/initializers/wrap_parameters.rb
new file mode 100644
index 0000000000..2f3c0db471
--- /dev/null
+++ b/activestorage/test/dummy/config/initializers/wrap_parameters.rb
@@ -0,0 +1,16 @@
+# frozen_string_literal: true
+
+# Be sure to restart your server when you modify this file.
+
+# This file contains settings for ActionController::ParamsWrapper which
+# is enabled by default.
+
+# Enable parameter wrapping for JSON. You can disable this by setting :format to an empty array.
+ActiveSupport.on_load(:action_controller) do
+  wrap_parameters format: [:json]
+end
+
+# To enable root element in JSON for ActiveRecord objects.
+# ActiveSupport.on_load(:active_record) do
+#   self.include_root_in_json = true
+# end
diff --git a/activestorage/test/dummy/config/routes.rb b/activestorage/test/dummy/config/routes.rb
new file mode 100644
index 0000000000..edf04d2d63
--- /dev/null
+++ b/activestorage/test/dummy/config/routes.rb
@@ -0,0 +1,4 @@
+# frozen_string_literal: true
+
+Rails.application.routes.draw do
+end
diff --git a/railties/lib/rails/generators/rails/app/templates/config/secrets.yml b/activestorage/test/dummy/config/secrets.yml
index 8e995a5df1..77d1fc383a 100644
--- a/railties/lib/rails/generators/rails/app/templates/config/secrets.yml
+++ b/activestorage/test/dummy/config/secrets.yml
@@ -12,19 +12,21 @@
 
 # Shared secrets are available across all environments.
 
-shared:
-  api_key: 123
+# shared:
+#   api_key: a1B2c3D4e5F6
 
 # Environmental secrets are only available for that specific environment.
 
 development:
-  secret_key_base: <%= app_secret %>
+  secret_key_base: e0ef5744b10d988669be6b2660c259749779964f3dcb487fd6199743b3558e2d89f7681d6a15d16d144e28979cbdae41885f4fb4c2cf56ff92ac22df282ffb66
 
 test:
-  secret_key_base: <%= app_secret %>
+  secret_key_base: 6fb1f3a828a8dcd6ac8dc07b43be4a5265ad64379120d417252a1578fe1f790e7b85ade4f95994de1ac8fb78581690de6e3a6ac4af36a0f0139667418c750d05
 
-# Do not keep production secrets in the repository,
-# instead read values from the environment.
+# Do not keep production secrets in the unencrypted secrets file.
+# Instead, either read values from the environment.
+# Or, use `bin/rails secrets:setup` to configure encrypted secrets
+# and move the `production:` environment over there.
 
 production:
-  secret_key_base: <%%= ENV["SECRET_KEY_BASE"] %>
+  secret_key_base: <%= ENV["SECRET_KEY_BASE"] %>
diff --git a/railties/lib/rails/generators/rails/app/templates/config/spring.rb b/activestorage/test/dummy/config/spring.rb
index c9119b40c0..ff5ba06b6d 100644
--- a/railties/lib/rails/generators/rails/app/templates/config/spring.rb
+++ b/activestorage/test/dummy/config/spring.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 %w(
   .ruby-version
   .rbenv-vars
diff --git a/activestorage/test/dummy/config/storage.yml b/activestorage/test/dummy/config/storage.yml
new file mode 100644
index 0000000000..2c6762e0d6
--- /dev/null
+++ b/activestorage/test/dummy/config/storage.yml
@@ -0,0 +1,3 @@
+local:
+  service: Disk
+  root: <%= Rails.root.join("storage") %>
diff --git a/activestorage/test/dummy/lib/assets/.keep b/activestorage/test/dummy/lib/assets/.keep
new file mode 100644
index 0000000000..e69de29bb2
--- /dev/null
+++ b/activestorage/test/dummy/lib/assets/.keep
diff --git a/activestorage/test/dummy/log/.keep b/activestorage/test/dummy/log/.keep
new file mode 100644
index 0000000000..e69de29bb2
--- /dev/null
+++ b/activestorage/test/dummy/log/.keep
diff --git a/activestorage/test/dummy/package.json b/activestorage/test/dummy/package.json
new file mode 100644
index 0000000000..caa2d7bb3f
--- /dev/null
+++ b/activestorage/test/dummy/package.json
@@ -0,0 +1,5 @@
+{
+  "name": "dummy",
+  "private": true,
+  "dependencies": {}
+}
diff --git a/activestorage/test/dummy/public/404.html b/activestorage/test/dummy/public/404.html
new file mode 100644
index 0000000000..2be3af26fc
--- /dev/null
+++ b/activestorage/test/dummy/public/404.html
@@ -0,0 +1,67 @@
+<!DOCTYPE html>
+<html>
+<head>
+  <title>The page you were looking for doesn't exist (404)</title>
+  <meta name="viewport" content="width=device-width,initial-scale=1">
+  <style>
+  .rails-default-error-page {
+    background-color: #EFEFEF;
+    color: #2E2F30;
+    text-align: center;
+    font-family: arial, sans-serif;
+    margin: 0;
+  }
+
+  .rails-default-error-page div.dialog {
+    width: 95%;
+    max-width: 33em;
+    margin: 4em auto 0;
+  }
+
+  .rails-default-error-page div.dialog > div {
+    border: 1px solid #CCC;
+    border-right-color: #999;
+    border-left-color: #999;
+    border-bottom-color: #BBB;
+    border-top: #B00100 solid 4px;
+    border-top-left-radius: 9px;
+    border-top-right-radius: 9px;
+    background-color: white;
+    padding: 7px 12% 0;
+    box-shadow: 0 3px 8px rgba(50, 50, 50, 0.17);
+  }
+
+  .rails-default-error-page h1 {
+    font-size: 100%;
+    color: #730E15;
+    line-height: 1.5em;
+  }
+
+  .rails-default-error-page div.dialog > p {
+    margin: 0 0 1em;
+    padding: 1em;
+    background-color: #F7F7F7;
+    border: 1px solid #CCC;
+    border-right-color: #999;
+    border-left-color: #999;
+    border-bottom-color: #999;
+    border-bottom-left-radius: 4px;
+    border-bottom-right-radius: 4px;
+    border-top-color: #DADADA;
+    color: #666;
+    box-shadow: 0 3px 8px rgba(50, 50, 50, 0.17);
+  }
+  </style>
+</head>
+
+<body class="rails-default-error-page">
+  <!-- This file lives in public/404.html -->
+  <div class="dialog">
+    <div>
+      <h1>The page you were looking for doesn't exist.</h1>
+      <p>You may have mistyped the address or the page may have moved.</p>
+    </div>
+    <p>If you are the application owner check the logs for more information.</p>
+  </div>
+</body>
+</html>
diff --git a/activestorage/test/dummy/public/422.html b/activestorage/test/dummy/public/422.html
new file mode 100644
index 0000000000..c08eac0d1d
--- /dev/null
+++ b/activestorage/test/dummy/public/422.html
@@ -0,0 +1,67 @@
+<!DOCTYPE html>
+<html>
+<head>
+  <title>The change you wanted was rejected (422)</title>
+  <meta name="viewport" content="width=device-width,initial-scale=1">
+  <style>
+  .rails-default-error-page {
+    background-color: #EFEFEF;
+    color: #2E2F30;
+    text-align: center;
+    font-family: arial, sans-serif;
+    margin: 0;
+  }
+
+  .rails-default-error-page div.dialog {
+    width: 95%;
+    max-width: 33em;
+    margin: 4em auto 0;
+  }
+
+  .rails-default-error-page div.dialog > div {
+    border: 1px solid #CCC;
+    border-right-color: #999;
+    border-left-color: #999;
+    border-bottom-color: #BBB;
+    border-top: #B00100 solid 4px;
+    border-top-left-radius: 9px;
+    border-top-right-radius: 9px;
+    background-color: white;
+    padding: 7px 12% 0;
+    box-shadow: 0 3px 8px rgba(50, 50, 50, 0.17);
+  }
+
+  .rails-default-error-page h1 {
+    font-size: 100%;
+    color: #730E15;
+    line-height: 1.5em;
+  }
+
+  .rails-default-error-page div.dialog > p {
+    margin: 0 0 1em;
+    padding: 1em;
+    background-color: #F7F7F7;
+    border: 1px solid #CCC;
+    border-right-color: #999;
+    border-left-color: #999;
+    border-bottom-color: #999;
+    border-bottom-left-radius: 4px;
+    border-bottom-right-radius: 4px;
+    border-top-color: #DADADA;
+    color: #666;
+    box-shadow: 0 3px 8px rgba(50, 50, 50, 0.17);
+  }
+  </style>
+</head>
+
+<body class="rails-default-error-page">
+  <!-- This file lives in public/422.html -->
+  <div class="dialog">
+    <div>
+      <h1>The change you wanted was rejected.</h1>
+      <p>Maybe you tried to change something you didn't have access to.</p>
+    </div>
+    <p>If you are the application owner check the logs for more information.</p>
+  </div>
+</body>
+</html>
diff --git a/activestorage/test/dummy/public/500.html b/activestorage/test/dummy/public/500.html
new file mode 100644
index 0000000000..78a030af22
--- /dev/null
+++ b/activestorage/test/dummy/public/500.html
@@ -0,0 +1,66 @@
+<!DOCTYPE html>
+<html>
+<head>
+  <title>We're sorry, but something went wrong (500)</title>
+  <meta name="viewport" content="width=device-width,initial-scale=1">
+  <style>
+  .rails-default-error-page {
+    background-color: #EFEFEF;
+    color: #2E2F30;
+    text-align: center;
+    font-family: arial, sans-serif;
+    margin: 0;
+  }
+
+  .rails-default-error-page div.dialog {
+    width: 95%;
+    max-width: 33em;
+    margin: 4em auto 0;
+  }
+
+  .rails-default-error-page div.dialog > div {
+    border: 1px solid #CCC;
+    border-right-color: #999;
+    border-left-color: #999;
+    border-bottom-color: #BBB;
+    border-top: #B00100 solid 4px;
+    border-top-left-radius: 9px;
+    border-top-right-radius: 9px;
+    background-color: white;
+    padding: 7px 12% 0;
+    box-shadow: 0 3px 8px rgba(50, 50, 50, 0.17);
+  }
+
+  .rails-default-error-page h1 {
+    font-size: 100%;
+    color: #730E15;
+    line-height: 1.5em;
+  }
+
+  .rails-default-error-page div.dialog > p {
+    margin: 0 0 1em;
+    padding: 1em;
+    background-color: #F7F7F7;
+    border: 1px solid #CCC;
+    border-right-color: #999;
+    border-left-color: #999;
+    border-bottom-color: #999;
+    border-bottom-left-radius: 4px;
+    border-bottom-right-radius: 4px;
+    border-top-color: #DADADA;
+    color: #666;
+    box-shadow: 0 3px 8px rgba(50, 50, 50, 0.17);
+  }
+  </style>
+</head>
+
+<body class="rails-default-error-page">
+  <!-- This file lives in public/500.html -->
+  <div class="dialog">
+    <div>
+      <h1>We're sorry, but something went wrong.</h1>
+    </div>
+    <p>If you are the application owner check the logs for more information.</p>
+  </div>
+</body>
+</html>
diff --git a/activestorage/test/dummy/public/apple-touch-icon-precomposed.png b/activestorage/test/dummy/public/apple-touch-icon-precomposed.png
new file mode 100644
index 0000000000..e69de29bb2
--- /dev/null
+++ b/activestorage/test/dummy/public/apple-touch-icon-precomposed.png
diff --git a/activestorage/test/dummy/public/apple-touch-icon.png b/activestorage/test/dummy/public/apple-touch-icon.png
new file mode 100644
index 0000000000..e69de29bb2
--- /dev/null
+++ b/activestorage/test/dummy/public/apple-touch-icon.png
diff --git a/activestorage/test/dummy/public/favicon.ico b/activestorage/test/dummy/public/favicon.ico
new file mode 100644
index 0000000000..e69de29bb2
--- /dev/null
+++ b/activestorage/test/dummy/public/favicon.ico
diff --git a/activestorage/test/fixtures/files/icon.psd b/activestorage/test/fixtures/files/icon.psd
new file mode 100644
index 0000000000..631fceeaab
--- /dev/null
+++ b/activestorage/test/fixtures/files/icon.psd
diff --git a/activestorage/test/fixtures/files/icon.svg b/activestorage/test/fixtures/files/icon.svg
new file mode 100644
index 0000000000..6cfb0e241e
--- /dev/null
+++ b/activestorage/test/fixtures/files/icon.svg
@@ -0,0 +1,13 @@
+<!-- The XML declaration is intentionally omitted. -->
+<svg width="792px" height="584px" viewBox="0 0 792 584" version="1.1" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink">
+    <path d="M9.51802657,28.724593 C9.51802657,18.2155955 18.1343454,9.60822622 28.6542694,9.60822622 L763.245541,9.60822622 C773.765465,9.60822622 782.381784,18.2155955 782.381784,28.724593 L782.381784,584 L792,584 L792,28.724593 C792,12.911054 779.075522,0 763.245541,0 L28.7544592,0 C12.9244782,0 0,12.911054 0,28.724593 L0,584 L9.61821632,584 C9.51802657,584 9.51802657,28.724593 9.51802657,28.724593 L9.51802657,28.724593 Z" id="Shape" opacity="0.3" fill="#CCCCCC"></path>
+    <circle id="Oval" fill="#FFCC33" cx="119.1" cy="147.2" r="33"></circle>
+    <circle id="Oval" fill="#3399FF" cx="119.1" cy="281.1" r="33"></circle>
+    <circle id="Oval" fill="#FF3333" cx="676.1" cy="376.8" r="33"></circle>
+    <circle id="Oval" fill="#FFCC33" cx="119.1" cy="477.2" r="33"></circle>
+    <rect id="Rectangle-path" opacity="0.75" fill="#CCCCCC" x="176.5" y="130.5" width="442.1" height="33.5"></rect>
+    <rect id="Rectangle-path" opacity="0.75" fill="#CCCCCC" x="176.5" y="183.1" width="442.1" height="33.5"></rect>
+    <rect id="Rectangle-path" opacity="0.75" fill="#CCCCCC" x="176.5" y="265.8" width="442.1" height="33.5"></rect>
+    <rect id="Rectangle-path" opacity="0.75" fill="#CCCCCC" x="176.5" y="363.4" width="442.1" height="33.5"></rect>
+    <rect id="Rectangle-path" opacity="0.75" fill="#CCCCCC" x="176.5" y="465.3" width="442.1" height="33.5"></rect>
+</svg>
diff --git a/activestorage/test/fixtures/files/image.gif b/activestorage/test/fixtures/files/image.gif
new file mode 100644
index 0000000000..90c05f671c
--- /dev/null
+++ b/activestorage/test/fixtures/files/image.gif
diff --git a/activestorage/test/fixtures/files/racecar.jpg b/activestorage/test/fixtures/files/racecar.jpg
new file mode 100644
index 0000000000..934b4caa22
--- /dev/null
+++ b/activestorage/test/fixtures/files/racecar.jpg
diff --git a/activestorage/test/fixtures/files/report.pdf b/activestorage/test/fixtures/files/report.pdf
new file mode 100644
index 0000000000..cccb9b5d64
--- /dev/null
+++ b/activestorage/test/fixtures/files/report.pdf
diff --git a/activestorage/test/fixtures/files/rotated_video.mp4 b/activestorage/test/fixtures/files/rotated_video.mp4
new file mode 100644
index 0000000000..4c7a4e9e57
--- /dev/null
+++ b/activestorage/test/fixtures/files/rotated_video.mp4
diff --git a/activestorage/test/fixtures/files/video.mp4 b/activestorage/test/fixtures/files/video.mp4
new file mode 100644
index 0000000000..8fb1c5b24d
--- /dev/null
+++ b/activestorage/test/fixtures/files/video.mp4
diff --git a/activestorage/test/fixtures/files/video_without_video_stream.mp4 b/activestorage/test/fixtures/files/video_without_video_stream.mp4
new file mode 100644
index 0000000000..e6a55f868b
--- /dev/null
+++ b/activestorage/test/fixtures/files/video_without_video_stream.mp4
diff --git a/activestorage/test/models/attachments_test.rb b/activestorage/test/models/attachments_test.rb
new file mode 100644
index 0000000000..20eec3c220
--- /dev/null
+++ b/activestorage/test/models/attachments_test.rb
@@ -0,0 +1,347 @@
+# frozen_string_literal: true
+
+require "test_helper"
+require "database/setup"
+
+class ActiveStorage::AttachmentsTest < ActiveSupport::TestCase
+  include ActiveJob::TestHelper
+
+  setup { @user = User.create!(name: "DHH") }
+
+  teardown { ActiveStorage::Blob.all.each(&:purge) }
+
+  test "attach existing blob" do
+    @user.avatar.attach create_blob(filename: "funky.jpg")
+    assert_equal "funky.jpg", @user.avatar.filename.to_s
+  end
+
+  test "attach existing blob from a signed ID" do
+    @user.avatar.attach create_blob(filename: "funky.jpg").signed_id
+    assert_equal "funky.jpg", @user.avatar.filename.to_s
+  end
+
+  test "attach new blob from a Hash" do
+    @user.avatar.attach io: StringIO.new("STUFF"), filename: "town.jpg", content_type: "image/jpg"
+    assert_equal "town.jpg", @user.avatar.filename.to_s
+  end
+
+  test "attach new blob from an UploadedFile" do
+    file = file_fixture "racecar.jpg"
+    @user.avatar.attach Rack::Test::UploadedFile.new file.to_s
+    assert_equal "racecar.jpg", @user.avatar.filename.to_s
+  end
+
+  test "replace attached blob" do
+    @user.avatar.attach create_blob(filename: "funky.jpg")
+
+    perform_enqueued_jobs do
+      assert_no_difference -> { ActiveStorage::Blob.count } do
+        @user.avatar.attach create_blob(filename: "town.jpg")
+      end
+    end
+
+    assert_equal "town.jpg", @user.avatar.filename.to_s
+  end
+
+  test "replace attached blob unsuccessfully" do
+    @user.avatar.attach create_blob(filename: "funky.jpg")
+
+    perform_enqueued_jobs do
+      assert_raises do
+        @user.avatar.attach nil
+      end
+    end
+
+    assert_equal "funky.jpg", @user.reload.avatar.filename.to_s
+    assert ActiveStorage::Blob.service.exist?(@user.avatar.key)
+  end
+
+  test "attach blob to new record" do
+    user = User.new(name: "Jason")
+
+    assert_no_changes -> { user.new_record? } do
+      assert_no_difference -> { ActiveStorage::Attachment.count } do
+        user.avatar.attach create_blob(filename: "funky.jpg")
+      end
+    end
+
+    assert user.avatar.attached?
+    assert_equal "funky.jpg", user.avatar.filename.to_s
+
+    assert_difference -> { ActiveStorage::Attachment.count }, +1 do
+      user.save!
+    end
+
+    assert user.reload.avatar.attached?
+    assert_equal "funky.jpg", user.avatar.filename.to_s
+  end
+
+  test "build new record with attached blob" do
+    assert_no_difference -> { ActiveStorage::Attachment.count } do
+      @user = User.new(name: "Jason", avatar: { io: StringIO.new("STUFF"), filename: "town.jpg", content_type: "image/jpg" })
+    end
+
+    assert @user.new_record?
+    assert @user.avatar.attached?
+    assert_equal "town.jpg", @user.avatar.filename.to_s
+
+    @user.save!
+    assert @user.reload.avatar.attached?
+    assert_equal "town.jpg", @user.avatar.filename.to_s
+  end
+
+  test "access underlying associations of new blob" do
+    @user.avatar.attach create_blob(filename: "funky.jpg")
+    assert_equal @user, @user.avatar_attachment.record
+    assert_equal @user.avatar_attachment.blob, @user.avatar_blob
+    assert_equal "funky.jpg", @user.avatar_attachment.blob.filename.to_s
+  end
+
+  test "analyze newly-attached blob" do
+    perform_enqueued_jobs do
+      @user.avatar.attach create_file_blob
+    end
+
+    assert_equal 4104, @user.avatar.reload.metadata[:width]
+    assert_equal 2736, @user.avatar.metadata[:height]
+  end
+
+  test "analyze attached blob only once" do
+    blob = create_file_blob
+
+    perform_enqueued_jobs do
+      @user.avatar.attach blob
+    end
+
+    assert blob.reload.analyzed?
+
+    @user.avatar.attachment.destroy
+
+    assert_no_enqueued_jobs do
+      @user.reload.avatar.attach blob
+    end
+  end
+
+  test "preserve existing metadata when analyzing a newly-attached blob" do
+    blob = create_file_blob(metadata: { foo: "bar" })
+
+    perform_enqueued_jobs do
+      @user.avatar.attach blob
+    end
+
+    assert_equal "bar", blob.reload.metadata[:foo]
+  end
+
+  test "detach blob" do
+    @user.avatar.attach create_blob(filename: "funky.jpg")
+    avatar_blob_id = @user.avatar.blob.id
+    avatar_key = @user.avatar.key
+
+    @user.avatar.detach
+    assert_not @user.avatar.attached?
+    assert ActiveStorage::Blob.exists?(avatar_blob_id)
+    assert ActiveStorage::Blob.service.exist?(avatar_key)
+  end
+
+  test "purge attached blob" do
+    @user.avatar.attach create_blob(filename: "funky.jpg")
+    avatar_key = @user.avatar.key
+
+    @user.avatar.purge
+    assert_not @user.avatar.attached?
+    assert_not ActiveStorage::Blob.service.exist?(avatar_key)
+  end
+
+  test "purge attached blob later when the record is destroyed" do
+    @user.avatar.attach create_blob(filename: "funky.jpg")
+    avatar_key = @user.avatar.key
+
+    perform_enqueued_jobs do
+      @user.destroy
+
+      assert_nil ActiveStorage::Blob.find_by(key: avatar_key)
+      assert_not ActiveStorage::Blob.service.exist?(avatar_key)
+    end
+  end
+
+  test "find with attached blob" do
+    records = %w[alice bob].map do |name|
+      User.create!(name: name).tap do |user|
+        user.avatar.attach create_blob(filename: "#{name}.jpg")
+      end
+    end
+
+    users = User.where(id: records.map(&:id)).with_attached_avatar.all
+
+    assert_equal "alice.jpg", users.first.avatar.filename.to_s
+    assert_equal "bob.jpg", users.second.avatar.filename.to_s
+  end
+
+
+  test "attach existing blobs" do
+    @user.highlights.attach create_blob(filename: "funky.jpg"), create_blob(filename: "wonky.jpg")
+
+    assert_equal "funky.jpg", @user.highlights.first.filename.to_s
+    assert_equal "wonky.jpg", @user.highlights.second.filename.to_s
+  end
+
+  test "attach new blobs" do
+    @user.highlights.attach(
+      { io: StringIO.new("STUFF"), filename: "town.jpg", content_type: "image/jpg" },
+      { io: StringIO.new("IT"), filename: "country.jpg", content_type: "image/jpg" })
+
+    assert_equal "town.jpg", @user.highlights.first.filename.to_s
+    assert_equal "country.jpg", @user.highlights.second.filename.to_s
+  end
+
+  test "attach blobs to new record" do
+    user = User.new(name: "Jason")
+
+    assert_no_changes -> { user.new_record? } do
+      assert_no_difference -> { ActiveStorage::Attachment.count } do
+        user.highlights.attach(
+          { io: StringIO.new("STUFF"), filename: "town.jpg", content_type: "image/jpg" },
+          { io: StringIO.new("IT"), filename: "country.jpg", content_type: "image/jpg" })
+      end
+    end
+
+    assert user.highlights.attached?
+    assert_equal "town.jpg", user.highlights.first.filename.to_s
+    assert_equal "country.jpg", user.highlights.second.filename.to_s
+
+    assert_difference -> { ActiveStorage::Attachment.count }, +2 do
+      user.save!
+    end
+
+    assert user.reload.highlights.attached?
+    assert_equal "town.jpg", user.highlights.first.filename.to_s
+    assert_equal "country.jpg", user.highlights.second.filename.to_s
+  end
+
+  test "build new record with attached blobs" do
+    assert_no_difference -> { ActiveStorage::Attachment.count } do
+      @user = User.new(name: "Jason", highlights: [
+        { io: StringIO.new("STUFF"), filename: "town.jpg", content_type: "image/jpg" },
+        { io: StringIO.new("IT"), filename: "country.jpg", content_type: "image/jpg" }])
+    end
+
+    assert @user.new_record?
+    assert @user.highlights.attached?
+    assert_equal "town.jpg", @user.highlights.first.filename.to_s
+    assert_equal "country.jpg", @user.highlights.second.filename.to_s
+
+    @user.save!
+    assert @user.reload.highlights.attached?
+    assert_equal "town.jpg", @user.highlights.first.filename.to_s
+    assert_equal "country.jpg", @user.highlights.second.filename.to_s
+  end
+
+  test "find attached blobs" do
+    @user.highlights.attach(
+      { io: StringIO.new("STUFF"), filename: "town.jpg", content_type: "image/jpg" },
+      { io: StringIO.new("IT"), filename: "country.jpg", content_type: "image/jpg" })
+
+    highlights = User.where(id: @user.id).with_attached_highlights.first.highlights
+
+    assert_equal "town.jpg", highlights.first.filename.to_s
+    assert_equal "country.jpg", highlights.second.filename.to_s
+  end
+
+  test "access underlying associations of new blobs" do
+    @user.highlights.attach(
+      { io: StringIO.new("STUFF"), filename: "town.jpg", content_type: "image/jpg" },
+      { io: StringIO.new("IT"), filename: "country.jpg", content_type: "image/jpg" })
+
+    assert_equal @user, @user.highlights_attachments.first.record
+    assert_equal @user.highlights_attachments.collect(&:blob).sort, @user.highlights_blobs.sort
+    assert_equal "town.jpg", @user.highlights_attachments.first.blob.filename.to_s
+  end
+
+  test "analyze newly-attached blobs" do
+    perform_enqueued_jobs do
+      @user.highlights.attach(
+        create_file_blob(filename: "racecar.jpg", content_type: "image/jpeg"),
+        create_file_blob(filename: "video.mp4", content_type: "video/mp4"))
+    end
+
+    assert_equal 4104, @user.highlights.first.metadata[:width]
+    assert_equal 2736, @user.highlights.first.metadata[:height]
+
+    assert_equal 640, @user.highlights.second.metadata[:width]
+    assert_equal 480, @user.highlights.second.metadata[:height]
+  end
+
+  test "analyze attached blobs only once" do
+    blobs = [
+      create_file_blob(filename: "racecar.jpg", content_type: "image/jpeg"),
+      create_file_blob(filename: "video.mp4", content_type: "video/mp4")
+    ]
+
+    perform_enqueued_jobs do
+      @user.highlights.attach(blobs)
+    end
+
+    assert blobs.each(&:reload).all?(&:analyzed?)
+
+    @user.highlights.attachments.destroy_all
+
+    assert_no_enqueued_jobs do
+      @user.highlights.attach(blobs)
+    end
+  end
+
+  test "preserve existing metadata when analyzing newly-attached blobs" do
+    blobs = [
+      create_file_blob(filename: "racecar.jpg", content_type: "image/jpeg", metadata: { foo: "bar" }),
+      create_file_blob(filename: "video.mp4", content_type: "video/mp4", metadata: { foo: "bar" })
+    ]
+
+    perform_enqueued_jobs do
+      @user.highlights.attach(blobs)
+    end
+
+    blobs.each do |blob|
+      assert_equal "bar", blob.reload.metadata[:foo]
+    end
+  end
+
+  test "detach blobs" do
+    @user.highlights.attach create_blob(filename: "funky.jpg"), create_blob(filename: "wonky.jpg")
+    highlight_blob_ids = @user.highlights.collect { |highlight| highlight.blob.id }
+    highlight_keys = @user.highlights.collect(&:key)
+
+    @user.highlights.detach
+    assert_not @user.highlights.attached?
+
+    assert ActiveStorage::Blob.exists?(highlight_blob_ids.first)
+    assert ActiveStorage::Blob.exists?(highlight_blob_ids.second)
+
+    assert ActiveStorage::Blob.service.exist?(highlight_keys.first)
+    assert ActiveStorage::Blob.service.exist?(highlight_keys.second)
+  end
+
+  test "purge attached blobs" do
+    @user.highlights.attach create_blob(filename: "funky.jpg"), create_blob(filename: "wonky.jpg")
+    highlight_keys = @user.highlights.collect(&:key)
+
+    @user.highlights.purge
+    assert_not @user.highlights.attached?
+    assert_not ActiveStorage::Blob.service.exist?(highlight_keys.first)
+    assert_not ActiveStorage::Blob.service.exist?(highlight_keys.second)
+  end
+
+  test "purge attached blobs later when the record is destroyed" do
+    @user.highlights.attach create_blob(filename: "funky.jpg"), create_blob(filename: "wonky.jpg")
+    highlight_keys = @user.highlights.collect(&:key)
+
+    perform_enqueued_jobs do
+      @user.destroy
+
+      assert_nil ActiveStorage::Blob.find_by(key: highlight_keys.first)
+      assert_not ActiveStorage::Blob.service.exist?(highlight_keys.first)
+
+      assert_nil ActiveStorage::Blob.find_by(key: highlight_keys.second)
+      assert_not ActiveStorage::Blob.service.exist?(highlight_keys.second)
+    end
+  end
+end
diff --git a/activestorage/test/models/blob_test.rb b/activestorage/test/models/blob_test.rb
new file mode 100644
index 0000000000..f94e65ed77
--- /dev/null
+++ b/activestorage/test/models/blob_test.rb
@@ -0,0 +1,64 @@
+# frozen_string_literal: true
+
+require "test_helper"
+require "database/setup"
+
+class ActiveStorage::BlobTest < ActiveSupport::TestCase
+  test "create after upload sets byte size and checksum" do
+    data = "Hello world!"
+    blob = create_blob data: data
+
+    assert_equal data, blob.download
+    assert_equal data.length, blob.byte_size
+    assert_equal Digest::MD5.base64digest(data), blob.checksum
+  end
+
+  test "text?" do
+    blob = create_blob data: "Hello world!"
+    assert blob.text?
+    assert_not blob.audio?
+  end
+
+  test "download yields chunks" do
+    blob   = create_blob data: "a" * 75.kilobytes
+    chunks = []
+
+    blob.download do |chunk|
+      chunks << chunk
+    end
+
+    assert_equal 2, chunks.size
+    assert_equal "a" * 64.kilobytes, chunks.first
+    assert_equal "a" * 11.kilobytes, chunks.second
+  end
+
+  test "urls expiring in 5 minutes" do
+    blob = create_blob
+
+    freeze_time do
+      assert_equal expected_url_for(blob), blob.service_url
+      assert_equal expected_url_for(blob, disposition: :attachment), blob.service_url(disposition: :attachment)
+    end
+  end
+
+  test "purge deletes file from external service" do
+    blob = create_blob
+
+    blob.purge
+    assert_not ActiveStorage::Blob.service.exist?(blob.key)
+  end
+
+  test "purge deletes variants from external service" do
+    blob = create_file_blob
+    variant = blob.variant(resize: "100>").processed
+
+    blob.purge
+    assert_not ActiveStorage::Blob.service.exist?(variant.key)
+  end
+
+  private
+    def expected_url_for(blob, disposition: :inline)
+      query_string = { content_type: blob.content_type, disposition: "#{disposition}; #{blob.filename.parameters}" }.to_param
+      "/rails/active_storage/disk/#{ActiveStorage.verifier.generate(blob.key, expires_in: 5.minutes, purpose: :blob_key)}/#{blob.filename}?#{query_string}"
+    end
+end
diff --git a/activestorage/test/models/filename/parameters_test.rb b/activestorage/test/models/filename/parameters_test.rb
new file mode 100644
index 0000000000..431be00639
--- /dev/null
+++ b/activestorage/test/models/filename/parameters_test.rb
@@ -0,0 +1,32 @@
+# frozen_string_literal: true
+
+require "test_helper"
+
+class ActiveStorage::Filename::ParametersTest < ActiveSupport::TestCase
+  test "parameterizing a Latin filename" do
+    filename = ActiveStorage::Filename.new("racecar.jpg")
+
+    assert_equal %(filename="racecar.jpg"), filename.parameters.ascii
+    assert_equal "filename*=UTF-8''racecar.jpg", filename.parameters.utf8
+    assert_equal "#{filename.parameters.ascii}; #{filename.parameters.utf8}", filename.parameters.combined
+    assert_equal filename.parameters.combined, filename.parameters.to_s
+  end
+
+  test "parameterizing a Latin filename with accented characters" do
+    filename = ActiveStorage::Filename.new("råcëçâr.jpg")
+
+    assert_equal %(filename="racecar.jpg"), filename.parameters.ascii
+    assert_equal "filename*=UTF-8''r%C3%A5c%C3%AB%C3%A7%C3%A2r.jpg", filename.parameters.utf8
+    assert_equal "#{filename.parameters.ascii}; #{filename.parameters.utf8}", filename.parameters.combined
+    assert_equal filename.parameters.combined, filename.parameters.to_s
+  end
+
+  test "parameterizing a non-Latin filename" do
+    filename = ActiveStorage::Filename.new("автомобиль.jpg")
+
+    assert_equal %(filename="%3F%3F%3F%3F%3F%3F%3F%3F%3F%3F.jpg"), filename.parameters.ascii
+    assert_equal "filename*=UTF-8''%D0%B0%D0%B2%D1%82%D0%BE%D0%BC%D0%BE%D0%B1%D0%B8%D0%BB%D1%8C.jpg", filename.parameters.utf8
+    assert_equal "#{filename.parameters.ascii}; #{filename.parameters.utf8}", filename.parameters.combined
+    assert_equal filename.parameters.combined, filename.parameters.to_s
+  end
+end
diff --git a/activestorage/test/models/filename_test.rb b/activestorage/test/models/filename_test.rb
new file mode 100644
index 0000000000..88405e41c0
--- /dev/null
+++ b/activestorage/test/models/filename_test.rb
@@ -0,0 +1,56 @@
+# frozen_string_literal: true
+
+require "test_helper"
+
+class ActiveStorage::FilenameTest < ActiveSupport::TestCase
+  test "base" do
+    assert_equal "racecar", ActiveStorage::Filename.new("racecar.jpg").base
+    assert_equal "race.car", ActiveStorage::Filename.new("race.car.jpg").base
+    assert_equal "racecar", ActiveStorage::Filename.new("racecar").base
+  end
+
+  test "extension with delimiter" do
+    assert_equal ".jpg", ActiveStorage::Filename.new("racecar.jpg").extension_with_delimiter
+    assert_equal ".jpg", ActiveStorage::Filename.new("race.car.jpg").extension_with_delimiter
+    assert_equal "", ActiveStorage::Filename.new("racecar").extension_with_delimiter
+  end
+
+  test "extension without delimiter" do
+    assert_equal "jpg", ActiveStorage::Filename.new("racecar.jpg").extension_without_delimiter
+    assert_equal "jpg", ActiveStorage::Filename.new("race.car.jpg").extension_without_delimiter
+    assert_equal "", ActiveStorage::Filename.new("racecar").extension_without_delimiter
+  end
+
+  test "sanitize" do
+    "%$|:;/\t\r\n\\".each_char do |character|
+      filename = ActiveStorage::Filename.new("foo#{character}bar.pdf")
+      assert_equal "foo-bar.pdf", filename.sanitized
+      assert_equal "foo-bar.pdf", filename.to_s
+    end
+  end
+
+  test "sanitize transcodes to valid UTF-8" do
+    { "\xF6".dup.force_encoding(Encoding::ISO8859_1) => "ö",
+      "\xC3".dup.force_encoding(Encoding::ISO8859_1) => "Ã",
+      "\xAD" => "�",
+      "\xCF" => "�",
+      "\x00" => "",
+    }.each do |actual, expected|
+      assert_equal expected, ActiveStorage::Filename.new(actual).sanitized
+    end
+  end
+
+  test "strips RTL override chars used to spoof unsafe executables as docs" do
+    # Would be displayed in Windows as "evilexe.pdf" due to the right-to-left
+    # (RTL) override char!
+    assert_equal "evil-fdp.exe", ActiveStorage::Filename.new("evil\u{202E}fdp.exe").sanitized
+  end
+
+  test "compare case-insensitively" do
+    assert_operator ActiveStorage::Filename.new("foobar.pdf"), :==, ActiveStorage::Filename.new("FooBar.PDF")
+  end
+
+  test "compare sanitized" do
+    assert_operator ActiveStorage::Filename.new("foo-bar.pdf"), :==, ActiveStorage::Filename.new("foo\tbar.pdf")
+  end
+end
diff --git a/activestorage/test/models/preview_test.rb b/activestorage/test/models/preview_test.rb
new file mode 100644
index 0000000000..bcd8442f4b
--- /dev/null
+++ b/activestorage/test/models/preview_test.rb
@@ -0,0 +1,40 @@
+# frozen_string_literal: true
+
+require "test_helper"
+require "database/setup"
+
+class ActiveStorage::PreviewTest < ActiveSupport::TestCase
+  test "previewing a PDF" do
+    blob = create_file_blob(filename: "report.pdf", content_type: "application/pdf")
+    preview = blob.preview(resize: "640x280").processed
+
+    assert preview.image.attached?
+    assert_equal "report.png", preview.image.filename.to_s
+    assert_equal "image/png", preview.image.content_type
+
+    image = read_image(preview.image)
+    assert_equal 612, image.width
+    assert_equal 792, image.height
+  end
+
+  test "previewing an MP4 video" do
+    blob = create_file_blob(filename: "video.mp4", content_type: "video/mp4")
+    preview = blob.preview(resize: "640x280").processed
+
+    assert preview.image.attached?
+    assert_equal "video.png", preview.image.filename.to_s
+    assert_equal "image/png", preview.image.content_type
+
+    image = read_image(preview.image)
+    assert_equal 640, image.width
+    assert_equal 480, image.height
+  end
+
+  test "previewing an unpreviewable blob" do
+    blob = create_file_blob
+
+    assert_raises ActiveStorage::Blob::UnpreviewableError do
+      blob.preview resize: "640x280"
+    end
+  end
+end
diff --git a/activestorage/test/models/representation_test.rb b/activestorage/test/models/representation_test.rb
new file mode 100644
index 0000000000..29fe61aee4
--- /dev/null
+++ b/activestorage/test/models/representation_test.rb
@@ -0,0 +1,41 @@
+# frozen_string_literal: true
+
+require "test_helper"
+require "database/setup"
+
+class ActiveStorage::RepresentationTest < ActiveSupport::TestCase
+  test "representing an image" do
+    blob = create_file_blob
+    representation = blob.representation(resize: "100x100").processed
+
+    image = read_image(representation.image)
+    assert_equal 100, image.width
+    assert_equal 67, image.height
+  end
+
+  test "representing a PDF" do
+    blob = create_file_blob(filename: "report.pdf", content_type: "application/pdf")
+    representation = blob.representation(resize: "640x280").processed
+
+    image = read_image(representation.image)
+    assert_equal 612, image.width
+    assert_equal 792, image.height
+  end
+
+  test "representing an MP4 video" do
+    blob = create_file_blob(filename: "video.mp4", content_type: "video/mp4")
+    representation = blob.representation(resize: "640x280").processed
+
+    image = read_image(representation.image)
+    assert_equal 640, image.width
+    assert_equal 480, image.height
+  end
+
+  test "representing an unrepresentable blob" do
+    blob = create_blob
+
+    assert_raises ActiveStorage::Blob::UnrepresentableError do
+      blob.representation resize: "100x100"
+    end
+  end
+end
diff --git a/activestorage/test/models/variant_test.rb b/activestorage/test/models/variant_test.rb
new file mode 100644
index 0000000000..7157bfac3a
--- /dev/null
+++ b/activestorage/test/models/variant_test.rb
@@ -0,0 +1,72 @@
+# frozen_string_literal: true
+
+require "test_helper"
+require "database/setup"
+
+class ActiveStorage::VariantTest < ActiveSupport::TestCase
+  test "resized variation of JPEG blob" do
+    blob = create_file_blob(filename: "racecar.jpg")
+    variant = blob.variant(resize: "100x100").processed
+    assert_match(/racecar\.jpg/, variant.service_url)
+
+    image = read_image(variant)
+    assert_equal 100, image.width
+    assert_equal 67, image.height
+  end
+
+  test "resized and monochrome variation of JPEG blob" do
+    blob = create_file_blob(filename: "racecar.jpg")
+    variant = blob.variant(resize: "100x100", monochrome: true).processed
+    assert_match(/racecar\.jpg/, variant.service_url)
+
+    image = read_image(variant)
+    assert_equal 100, image.width
+    assert_equal 67, image.height
+    assert_match(/Gray/, image.colorspace)
+  end
+
+  test "center-weighted crop of JPEG blob" do
+    blob = create_file_blob(filename: "racecar.jpg")
+    variant = blob.variant(combine_options: {
+      gravity: "center",
+      resize: "100x100^",
+      crop: "100x100+0+0",
+    }).processed
+    assert_match(/racecar\.jpg/, variant.service_url)
+
+    image = read_image(variant)
+    assert_equal 100, image.width
+    assert_equal 100, image.height
+  end
+
+  test "resized variation of PSD blob" do
+    blob = create_file_blob(filename: "icon.psd", content_type: "image/vnd.adobe.photoshop")
+    variant = blob.variant(resize: "20x20").processed
+    assert_match(/icon\.png/, variant.service_url)
+
+    image = read_image(variant)
+    assert_equal "PNG", image.type
+    assert_equal 20, image.width
+    assert_equal 20, image.height
+  end
+
+  test "optimized variation of GIF blob" do
+    blob = create_file_blob(filename: "image.gif", content_type: "image/gif")
+
+    assert_nothing_raised do
+      blob.variant(layers: "Optimize").processed
+    end
+  end
+
+  test "variation of invariable blob" do
+    assert_raises ActiveStorage::Blob::InvariableError do
+      create_file_blob(filename: "report.pdf", content_type: "application/pdf").variant(resize: "100x100")
+    end
+  end
+
+  test "service_url doesn't grow in length despite long variant options" do
+    blob = create_file_blob(filename: "racecar.jpg")
+    variant = blob.variant(font: "a" * 10_000).processed
+    assert_operator variant.service_url.length, :<, 500
+  end
+end
diff --git a/activestorage/test/previewer/pdf_previewer_test.rb b/activestorage/test/previewer/pdf_previewer_test.rb
new file mode 100644
index 0000000000..fe32f39be4
--- /dev/null
+++ b/activestorage/test/previewer/pdf_previewer_test.rb
@@ -0,0 +1,23 @@
+# frozen_string_literal: true
+
+require "test_helper"
+require "database/setup"
+
+require "active_storage/previewer/pdf_previewer"
+
+class ActiveStorage::Previewer::PDFPreviewerTest < ActiveSupport::TestCase
+  setup do
+    @blob = create_file_blob(filename: "report.pdf", content_type: "application/pdf")
+  end
+
+  test "previewing a PDF document" do
+    ActiveStorage::Previewer::PDFPreviewer.new(@blob).preview do |attachable|
+      assert_equal "image/png", attachable[:content_type]
+      assert_equal "report.png", attachable[:filename]
+
+      image = MiniMagick::Image.read(attachable[:io])
+      assert_equal 612, image.width
+      assert_equal 792, image.height
+    end
+  end
+end
diff --git a/activestorage/test/previewer/video_previewer_test.rb b/activestorage/test/previewer/video_previewer_test.rb
new file mode 100644
index 0000000000..dba9b0d7e2
--- /dev/null
+++ b/activestorage/test/previewer/video_previewer_test.rb
@@ -0,0 +1,23 @@
+# frozen_string_literal: true
+
+require "test_helper"
+require "database/setup"
+
+require "active_storage/previewer/video_previewer"
+
+class ActiveStorage::Previewer::VideoPreviewerTest < ActiveSupport::TestCase
+  setup do
+    @blob = create_file_blob(filename: "video.mp4", content_type: "video/mp4")
+  end
+
+  test "previewing an MP4 video" do
+    ActiveStorage::Previewer::VideoPreviewer.new(@blob).preview do |attachable|
+      assert_equal "image/png", attachable[:content_type]
+      assert_equal "video.png", attachable[:filename]
+
+      image = MiniMagick::Image.read(attachable[:io])
+      assert_equal 640, image.width
+      assert_equal 480, image.height
+    end
+  end
+end
diff --git a/activestorage/test/service/azure_storage_service_test.rb b/activestorage/test/service/azure_storage_service_test.rb
new file mode 100644
index 0000000000..be31bbe858
--- /dev/null
+++ b/activestorage/test/service/azure_storage_service_test.rb
@@ -0,0 +1,22 @@
+# frozen_string_literal: true
+
+require "service/shared_service_tests"
+require "uri"
+
+if SERVICE_CONFIGURATIONS[:azure]
+  class ActiveStorage::Service::AzureStorageServiceTest < ActiveSupport::TestCase
+    SERVICE = ActiveStorage::Service.configure(:azure, SERVICE_CONFIGURATIONS)
+
+    include ActiveStorage::Service::SharedServiceTests
+
+    test "signed URL generation" do
+      url = @service.url(FIXTURE_KEY, expires_in: 5.minutes,
+        disposition: :inline, filename: ActiveStorage::Filename.new("avatar.png"), content_type: "image/png")
+
+      assert_match(/(\S+)&rscd=inline%3B\+filename%3D%22avatar\.png%22%3B\+filename\*%3DUTF-8%27%27avatar\.png&rsct=image%2Fpng/, url)
+      assert_match SERVICE_CONFIGURATIONS[:azure][:container], url
+    end
+  end
+else
+  puts "Skipping Azure Storage Service tests because no Azure configuration was supplied"
+end
diff --git a/activestorage/test/service/configurations.example.yml b/activestorage/test/service/configurations.example.yml
new file mode 100644
index 0000000000..43cc013bc8
--- /dev/null
+++ b/activestorage/test/service/configurations.example.yml
@@ -0,0 +1,30 @@
+# s3:
+#   service: S3
+#   access_key_id: ""
+#   secret_access_key: ""
+#   region: ""
+#   bucket: ""
+#
+# gcs:
+#   service: GCS
+#   credentials: {
+#     type: "service_account",
+#     project_id: "",
+#     private_key_id: "",
+#     private_key: "",
+#     client_email: "",
+#     client_id: "",
+#     auth_uri: "https://accounts.google.com/o/oauth2/auth",
+#     token_uri: "https://accounts.google.com/o/oauth2/token",
+#     auth_provider_x509_cert_url: "https://www.googleapis.com/oauth2/v1/certs",
+#     client_x509_cert_url: ""
+#   }
+#   project:
+#   bucket:
+#
+# azure:
+#   service: AzureStorage
+#   path: ""
+#   storage_account_name: ""
+#   storage_access_key: ""
+#   container: ""
diff --git a/activestorage/test/service/configurations.yml.enc b/activestorage/test/service/configurations.yml.enc
new file mode 100644
index 0000000000..df11aac161
--- /dev/null
+++ b/activestorage/test/service/configurations.yml.enc
diff --git a/activestorage/test/service/configurator_test.rb b/activestorage/test/service/configurator_test.rb
new file mode 100644
index 0000000000..a2fd035e02
--- /dev/null
+++ b/activestorage/test/service/configurator_test.rb
@@ -0,0 +1,16 @@
+# frozen_string_literal: true
+
+require "service/shared_service_tests"
+
+class ActiveStorage::Service::ConfiguratorTest < ActiveSupport::TestCase
+  test "builds correct service instance based on service name" do
+    service = ActiveStorage::Service::Configurator.build(:foo, foo: { service: "Disk", root: "path" })
+    assert_instance_of ActiveStorage::Service::DiskService, service
+  end
+
+  test "raises error when passing non-existent service name" do
+    assert_raise RuntimeError do
+      ActiveStorage::Service::Configurator.build(:bigfoot, {})
+    end
+  end
+end
diff --git a/activestorage/test/service/disk_service_test.rb b/activestorage/test/service/disk_service_test.rb
new file mode 100644
index 0000000000..4a6361b920
--- /dev/null
+++ b/activestorage/test/service/disk_service_test.rb
@@ -0,0 +1,14 @@
+# frozen_string_literal: true
+
+require "service/shared_service_tests"
+
+class ActiveStorage::Service::DiskServiceTest < ActiveSupport::TestCase
+  SERVICE = ActiveStorage::Service::DiskService.new(root: File.join(Dir.tmpdir, "active_storage"))
+
+  include ActiveStorage::Service::SharedServiceTests
+
+  test "url generation" do
+    assert_match(/rails\/active_storage\/disk\/.*\/avatar\.png\?content_type=image%2Fpng&disposition=inline/,
+      @service.url(FIXTURE_KEY, expires_in: 5.minutes, disposition: :inline, filename: ActiveStorage::Filename.new("avatar.png"), content_type: "image/png"))
+  end
+end
diff --git a/activestorage/test/service/gcs_service_test.rb b/activestorage/test/service/gcs_service_test.rb
new file mode 100644
index 0000000000..7efcd60fb7
--- /dev/null
+++ b/activestorage/test/service/gcs_service_test.rb
@@ -0,0 +1,55 @@
+# frozen_string_literal: true
+
+require "service/shared_service_tests"
+require "net/http"
+
+if SERVICE_CONFIGURATIONS[:gcs]
+  class ActiveStorage::Service::GCSServiceTest < ActiveSupport::TestCase
+    SERVICE = ActiveStorage::Service.configure(:gcs, SERVICE_CONFIGURATIONS)
+
+    include ActiveStorage::Service::SharedServiceTests
+
+    test "direct upload" do
+      begin
+        key      = SecureRandom.base58(24)
+        data     = "Something else entirely!"
+        checksum = Digest::MD5.base64digest(data)
+        url      = @service.url_for_direct_upload(key, expires_in: 5.minutes, content_type: "text/plain", content_length: data.size, checksum: checksum)
+
+        uri = URI.parse url
+        request = Net::HTTP::Put.new uri.request_uri
+        request.body = data
+        request.add_field "Content-Type", "text/plain"
+        request.add_field "Content-MD5", checksum
+        Net::HTTP.start(uri.host, uri.port, use_ssl: true) do |http|
+          http.request request
+        end
+
+        assert_equal data, @service.download(key)
+      ensure
+        @service.delete key
+      end
+    end
+
+    test "signed URL generation" do
+      assert_match(/storage\.googleapis\.com\/.*response-content-disposition=inline.*test\.txt.*response-content-type=text%2Fplain/,
+        @service.url(FIXTURE_KEY, expires_in: 2.minutes, disposition: :inline, filename: ActiveStorage::Filename.new("test.txt"), content_type: "text/plain"))
+    end
+
+    test "signed URL response headers" do
+      begin
+        key  = SecureRandom.base58(24)
+        data = "Something else entirely!"
+        @service.upload(key, StringIO.new(data), checksum: Digest::MD5.base64digest(data))
+
+        url = @service.url(key, expires_in: 2.minutes, disposition: :inline, filename: ActiveStorage::Filename.new("test.txt"), content_type: "text/plain")
+        response = Net::HTTP.get_response(URI(url))
+        assert_equal "text/plain", response.header["Content-Type"]
+      ensure
+        @service.delete key
+      end
+    end
+  end
+else
+  puts "Skipping GCS Service tests because no GCS configuration was supplied"
+end
diff --git a/activestorage/test/service/mirror_service_test.rb b/activestorage/test/service/mirror_service_test.rb
new file mode 100644
index 0000000000..92101b1282
--- /dev/null
+++ b/activestorage/test/service/mirror_service_test.rb
@@ -0,0 +1,66 @@
+# frozen_string_literal: true
+
+require "service/shared_service_tests"
+
+class ActiveStorage::Service::MirrorServiceTest < ActiveSupport::TestCase
+  mirror_config = (1..3).map do |i|
+    [ "mirror_#{i}",
+      service: "Disk",
+      root: Dir.mktmpdir("active_storage_tests_mirror_#{i}") ]
+  end.to_h
+
+  config = mirror_config.merge \
+    mirror:   { service: "Mirror", primary: "primary", mirrors: mirror_config.keys },
+    primary:  { service: "Disk", root: Dir.mktmpdir("active_storage_tests_primary") }
+
+  SERVICE = ActiveStorage::Service.configure :mirror, config
+
+  include ActiveStorage::Service::SharedServiceTests
+
+  test "uploading to all services" do
+    begin
+      data = "Something else entirely!"
+      key  = upload(data, to: @service)
+
+      assert_equal data, SERVICE.primary.download(key)
+      SERVICE.mirrors.each do |mirror|
+        assert_equal data, mirror.download(key)
+      end
+    ensure
+      @service.delete key
+    end
+  end
+
+  test "downloading from primary service" do
+    data = "Something else entirely!"
+    key  = upload(data, to: SERVICE.primary)
+
+    assert_equal data, @service.download(key)
+  end
+
+  test "deleting from all services" do
+    @service.delete FIXTURE_KEY
+    assert_not SERVICE.primary.exist?(FIXTURE_KEY)
+    SERVICE.mirrors.each do |mirror|
+      assert_not mirror.exist?(FIXTURE_KEY)
+    end
+  end
+
+  test "URL generation in primary service" do
+    filename = ActiveStorage::Filename.new("test.txt")
+
+    freeze_time do
+      assert_equal SERVICE.primary.url(FIXTURE_KEY, expires_in: 2.minutes, disposition: :inline, filename: filename, content_type: "text/plain"),
+        @service.url(FIXTURE_KEY, expires_in: 2.minutes, disposition: :inline, filename: filename, content_type: "text/plain")
+    end
+  end
+
+  private
+    def upload(data, to:)
+      SecureRandom.base58(24).tap do |key|
+        io = StringIO.new(data).tap(&:read)
+        @service.upload key, io, checksum: Digest::MD5.base64digest(data)
+        assert io.eof?
+      end
+    end
+end
diff --git a/activestorage/test/service/s3_service_test.rb b/activestorage/test/service/s3_service_test.rb
new file mode 100644
index 0000000000..c3818422aa
--- /dev/null
+++ b/activestorage/test/service/s3_service_test.rb
@@ -0,0 +1,59 @@
+# frozen_string_literal: true
+
+require "service/shared_service_tests"
+require "net/http"
+
+if SERVICE_CONFIGURATIONS[:s3] && SERVICE_CONFIGURATIONS[:s3][:access_key_id].present?
+  class ActiveStorage::Service::S3ServiceTest < ActiveSupport::TestCase
+    SERVICE = ActiveStorage::Service.configure(:s3, SERVICE_CONFIGURATIONS)
+
+    include ActiveStorage::Service::SharedServiceTests
+
+    test "direct upload" do
+      begin
+        key      = SecureRandom.base58(24)
+        data     = "Something else entirely!"
+        checksum = Digest::MD5.base64digest(data)
+        url      = @service.url_for_direct_upload(key, expires_in: 5.minutes, content_type: "text/plain", content_length: data.size, checksum: checksum)
+
+        uri = URI.parse url
+        request = Net::HTTP::Put.new uri.request_uri
+        request.body = data
+        request.add_field "Content-Type", "text/plain"
+        request.add_field "Content-MD5", checksum
+        Net::HTTP.start(uri.host, uri.port, use_ssl: true) do |http|
+          http.request request
+        end
+
+        assert_equal data, @service.download(key)
+      ensure
+        @service.delete key
+      end
+    end
+
+    test "signed URL generation" do
+      url = @service.url(FIXTURE_KEY, expires_in: 5.minutes,
+        disposition: :inline, filename: ActiveStorage::Filename.new("avatar.png"), content_type: "image/png")
+
+      assert_match(/s3\.(\S+)?amazonaws.com.*response-content-disposition=inline.*avatar\.png.*response-content-type=image%2Fpng/, url)
+      assert_match SERVICE_CONFIGURATIONS[:s3][:bucket], url
+    end
+
+    test "uploading with server-side encryption" do
+      config  = SERVICE_CONFIGURATIONS.deep_merge(s3: { upload: { server_side_encryption: "AES256" } })
+      service = ActiveStorage::Service.configure(:s3, config)
+
+      begin
+        key  = SecureRandom.base58(24)
+        data = "Something else entirely!"
+        service.upload key, StringIO.new(data), checksum: Digest::MD5.base64digest(data)
+
+        assert_equal "AES256", service.bucket.object(key).server_side_encryption
+      ensure
+        service.delete key
+      end
+    end
+  end
+else
+  puts "Skipping S3 Service tests because no S3 configuration was supplied"
+end
diff --git a/activestorage/test/service/shared_service_tests.rb b/activestorage/test/service/shared_service_tests.rb
new file mode 100644
index 0000000000..ce28c4393a
--- /dev/null
+++ b/activestorage/test/service/shared_service_tests.rb
@@ -0,0 +1,96 @@
+# frozen_string_literal: true
+
+require "test_helper"
+require "active_support/core_ext/securerandom"
+
+module ActiveStorage::Service::SharedServiceTests
+  extend ActiveSupport::Concern
+
+  FIXTURE_KEY  = SecureRandom.base58(24)
+  FIXTURE_DATA = "\211PNG\r\n\032\n\000\000\000\rIHDR\000\000\000\020\000\000\000\020\001\003\000\000\000%=m\"\000\000\000\006PLTE\000\000\000\377\377\377\245\331\237\335\000\000\0003IDATx\234c\370\377\237\341\377_\206\377\237\031\016\2603\334?\314p\1772\303\315\315\f7\215\031\356\024\203\320\275\317\f\367\201R\314\f\017\300\350\377\177\000Q\206\027(\316]\233P\000\000\000\000IEND\256B`\202".dup.force_encoding(Encoding::BINARY)
+
+  included do
+    setup do
+      @service = self.class.const_get(:SERVICE)
+      @service.upload FIXTURE_KEY, StringIO.new(FIXTURE_DATA)
+    end
+
+    teardown do
+      @service.delete FIXTURE_KEY
+    end
+
+    test "uploading with integrity" do
+      begin
+        key  = SecureRandom.base58(24)
+        data = "Something else entirely!"
+        @service.upload(key, StringIO.new(data), checksum: Digest::MD5.base64digest(data))
+
+        assert_equal data, @service.download(key)
+      ensure
+        @service.delete key
+      end
+    end
+
+    test "uploading without integrity" do
+      begin
+        key  = SecureRandom.base58(24)
+        data = "Something else entirely!"
+
+        assert_raises(ActiveStorage::IntegrityError) do
+          @service.upload(key, StringIO.new(data), checksum: Digest::MD5.base64digest("bad data"))
+        end
+
+        assert_not @service.exist?(key)
+      ensure
+        @service.delete key
+      end
+    end
+
+    test "downloading" do
+      assert_equal FIXTURE_DATA, @service.download(FIXTURE_KEY)
+    end
+
+    test "downloading in chunks" do
+      chunks = []
+
+      @service.download(FIXTURE_KEY) do |chunk|
+        chunks << chunk
+      end
+
+      assert_equal [ FIXTURE_DATA ], chunks
+    end
+
+    test "existing" do
+      assert @service.exist?(FIXTURE_KEY)
+      assert_not @service.exist?(FIXTURE_KEY + "nonsense")
+    end
+
+    test "deleting" do
+      @service.delete FIXTURE_KEY
+      assert_not @service.exist?(FIXTURE_KEY)
+    end
+
+    test "deleting nonexistent key" do
+      assert_nothing_raised do
+        @service.delete SecureRandom.base58(24)
+      end
+    end
+
+    test "deleting by prefix" do
+      begin
+        @service.upload("a/a/a", StringIO.new(FIXTURE_DATA))
+        @service.upload("a/a/b", StringIO.new(FIXTURE_DATA))
+        @service.upload("a/b/a", StringIO.new(FIXTURE_DATA))
+
+        @service.delete_prefixed("a/a/")
+        assert_not @service.exist?("a/a/a")
+        assert_not @service.exist?("a/a/b")
+        assert @service.exist?("a/b/a")
+      ensure
+        @service.delete("a/a/a")
+        @service.delete("a/a/b")
+        @service.delete("a/b/a")
+      end
+    end
+  end
+end
diff --git a/activestorage/test/template/image_tag_test.rb b/activestorage/test/template/image_tag_test.rb
new file mode 100644
index 0000000000..80f183e0e3
--- /dev/null
+++ b/activestorage/test/template/image_tag_test.rb
@@ -0,0 +1,44 @@
+# frozen_string_literal: true
+
+require "test_helper"
+require "database/setup"
+
+class ActiveStorage::ImageTagTest < ActionView::TestCase
+  tests ActionView::Helpers::AssetTagHelper
+
+  setup do
+    @blob = create_file_blob filename: "racecar.jpg"
+  end
+
+  test "blob" do
+    assert_dom_equal %(<img src="#{polymorphic_url @blob}" />), image_tag(@blob)
+  end
+
+  test "variant" do
+    variant = @blob.variant(resize: "100x100")
+    assert_dom_equal %(<img src="#{polymorphic_url variant}" />), image_tag(variant)
+  end
+
+  test "preview" do
+    blob = create_file_blob(filename: "report.pdf", content_type: "application/pdf")
+    preview = blob.preview(resize: "100x100")
+    assert_dom_equal %(<img src="#{polymorphic_url preview}" />), image_tag(preview)
+  end
+
+  test "attachment" do
+    attachment = ActiveStorage::Attachment.new(blob: @blob)
+    assert_dom_equal %(<img src="#{polymorphic_url attachment}" />), image_tag(attachment)
+  end
+
+  test "error when attachment's empty" do
+    @user = User.create!(name: "DHH")
+
+    assert_not @user.avatar.attached?
+    assert_raises(ArgumentError) { image_tag(@user.avatar) }
+  end
+
+  test "error when object can't be resolved into url" do
+    unresolvable_object = ActionView::Helpers::AssetTagHelper
+    assert_raises(ArgumentError) { image_tag(unresolvable_object) }
+  end
+end
diff --git a/activestorage/test/test_helper.rb b/activestorage/test/test_helper.rb
new file mode 100644
index 0000000000..aaf1d452ea
--- /dev/null
+++ b/activestorage/test/test_helper.rb
@@ -0,0 +1,69 @@
+# frozen_string_literal: true
+
+ENV["RAILS_ENV"] ||= "test"
+require_relative "dummy/config/environment.rb"
+
+require "bundler/setup"
+require "active_support"
+require "active_support/test_case"
+require "active_support/testing/autorun"
+require "mini_magick"
+
+begin
+  require "byebug"
+rescue LoadError
+end
+
+require "active_job"
+ActiveJob::Base.queue_adapter = :test
+ActiveJob::Base.logger = ActiveSupport::Logger.new(nil)
+
+# Filter out Minitest backtrace while allowing backtrace from other libraries
+# to be shown.
+Minitest.backtrace_filter = Minitest::BacktraceFilter.new
+
+require "yaml"
+SERVICE_CONFIGURATIONS = begin
+  erb = ERB.new(Pathname.new(File.expand_path("service/configurations.yml", __dir__)).read)
+  configuration = YAML.load(erb.result) || {}
+  configuration.deep_symbolize_keys
+rescue Errno::ENOENT
+  puts "Missing service configuration file in test/service/configurations.yml"
+  {}
+end
+
+require "tmpdir"
+ActiveStorage::Blob.service = ActiveStorage::Service::DiskService.new(root: Dir.mktmpdir("active_storage_tests"))
+
+ActiveStorage.logger = ActiveSupport::Logger.new(nil)
+ActiveStorage.verifier = ActiveSupport::MessageVerifier.new("Testing")
+
+class ActiveSupport::TestCase
+  self.file_fixture_path = File.expand_path("fixtures/files", __dir__)
+
+  private
+    def create_blob(data: "Hello world!", filename: "hello.txt", content_type: "text/plain")
+      ActiveStorage::Blob.create_after_upload! io: StringIO.new(data), filename: filename, content_type: content_type
+    end
+
+    def create_file_blob(filename: "racecar.jpg", content_type: "image/jpeg", metadata: nil)
+      ActiveStorage::Blob.create_after_upload! io: file_fixture(filename).open, filename: filename, content_type: content_type, metadata: metadata
+    end
+
+    def create_blob_before_direct_upload(filename: "hello.txt", byte_size:, checksum:, content_type: "text/plain")
+      ActiveStorage::Blob.create_before_direct_upload! filename: filename, byte_size: byte_size, checksum: checksum, content_type: content_type
+    end
+
+    def read_image(blob_or_variant)
+      MiniMagick::Image.open blob_or_variant.service.send(:path_for, blob_or_variant.key)
+    end
+end
+
+require "global_id"
+GlobalID.app = "ActiveStorageExampleApp"
+ActiveRecord::Base.send :include, GlobalID::Identification
+
+class User < ActiveRecord::Base
+  has_one_attached :avatar
+  has_many_attached :highlights
+end
diff --git a/activestorage/webpack.config.js b/activestorage/webpack.config.js
new file mode 100644
index 0000000000..3a50eef470
--- /dev/null
+++ b/activestorage/webpack.config.js
@@ -0,0 +1,26 @@
+const path = require("path")
+
+module.exports = {
+  entry: {
+    "activestorage": path.resolve(__dirname, "app/javascript/activestorage/index.js"),
+  },
+
+  output: {
+    filename: "[name].js",
+    path: path.resolve(__dirname, "app/assets/javascripts"),
+    library: "ActiveStorage",
+    libraryTarget: "umd"
+  },
+
+  module: {
+    rules: [
+      {
+        test: /\.js$/,
+        exclude: /node_modules/,
+        use: {
+          loader: "babel-loader"
+        }
+      }
+    ]
+  }
+}
diff --git a/activestorage/yarn.lock b/activestorage/yarn.lock
new file mode 100644
index 0000000000..41742be201
--- /dev/null
+++ b/activestorage/yarn.lock
@@ -0,0 +1,3154 @@
+# THIS IS AN AUTOGENERATED FILE. DO NOT EDIT THIS FILE DIRECTLY.
+# yarn lockfile v1
+
+
+abbrev@1:
+  version "1.1.0"
+  resolved "https://registry.yarnpkg.com/abbrev/-/abbrev-1.1.0.tgz#d0554c2256636e2f56e7c2e5ad183f859428d81f"
+
+acorn-dynamic-import@^2.0.0:
+  version "2.0.2"
+  resolved "https://registry.yarnpkg.com/acorn-dynamic-import/-/acorn-dynamic-import-2.0.2.tgz#c752bd210bef679501b6c6cb7fc84f8f47158cc4"
+  dependencies:
+    acorn "^4.0.3"
+
+acorn-jsx@^3.0.0:
+  version "3.0.1"
+  resolved "https://registry.yarnpkg.com/acorn-jsx/-/acorn-jsx-3.0.1.tgz#afdf9488fb1ecefc8348f6fb22f464e32a58b36b"
+  dependencies:
+    acorn "^3.0.4"
+
+acorn@^3.0.4:
+  version "3.3.0"
+  resolved "https://registry.yarnpkg.com/acorn/-/acorn-3.3.0.tgz#45e37fb39e8da3f25baee3ff5369e2bb5f22017a"
+
+acorn@^4.0.3:
+  version "4.0.13"
+  resolved "https://registry.yarnpkg.com/acorn/-/acorn-4.0.13.tgz#105495ae5361d697bd195c825192e1ad7f253787"
+
+acorn@^5.0.0, acorn@^5.0.1:
+  version "5.1.1"
+  resolved "https://registry.yarnpkg.com/acorn/-/acorn-5.1.1.tgz#53fe161111f912ab999ee887a90a0bc52822fd75"
+
+ajv-keywords@^1.0.0:
+  version "1.5.1"
+  resolved "https://registry.yarnpkg.com/ajv-keywords/-/ajv-keywords-1.5.1.tgz#314dd0a4b3368fad3dfcdc54ede6171b886daf3c"
+
+ajv-keywords@^2.0.0:
+  version "2.1.0"
+  resolved "https://registry.yarnpkg.com/ajv-keywords/-/ajv-keywords-2.1.0.tgz#a296e17f7bfae7c1ce4f7e0de53d29cb32162df0"
+
+ajv@^4.7.0, ajv@^4.9.1:
+  version "4.11.8"
+  resolved "https://registry.yarnpkg.com/ajv/-/ajv-4.11.8.tgz#82ffb02b29e662ae53bdc20af15947706739c536"
+  dependencies:
+    co "^4.6.0"
+    json-stable-stringify "^1.0.1"
+
+ajv@^5.1.5, ajv@^5.2.0:
+  version "5.2.2"
+  resolved "https://registry.yarnpkg.com/ajv/-/ajv-5.2.2.tgz#47c68d69e86f5d953103b0074a9430dc63da5e39"
+  dependencies:
+    co "^4.6.0"
+    fast-deep-equal "^1.0.0"
+    json-schema-traverse "^0.3.0"
+    json-stable-stringify "^1.0.1"
+
+align-text@^0.1.1, align-text@^0.1.3:
+  version "0.1.4"
+  resolved "https://registry.yarnpkg.com/align-text/-/align-text-0.1.4.tgz#0cd90a561093f35d0a99256c22b7069433fad117"
+  dependencies:
+    kind-of "^3.0.2"
+    longest "^1.0.1"
+    repeat-string "^1.5.2"
+
+ansi-escapes@^2.0.0:
+  version "2.0.0"
+  resolved "https://registry.yarnpkg.com/ansi-escapes/-/ansi-escapes-2.0.0.tgz#5bae52be424878dd9783e8910e3fc2922e83c81b"
+
+ansi-regex@^2.0.0:
+  version "2.1.1"
+  resolved "https://registry.yarnpkg.com/ansi-regex/-/ansi-regex-2.1.1.tgz#c3b33ab5ee360d86e0e628f0468ae7ef27d654df"
+
+ansi-regex@^3.0.0:
+  version "3.0.0"
+  resolved "https://registry.yarnpkg.com/ansi-regex/-/ansi-regex-3.0.0.tgz#ed0317c322064f79466c02966bddb605ab37d998"
+
+ansi-styles@^2.2.1:
+  version "2.2.1"
+  resolved "https://registry.yarnpkg.com/ansi-styles/-/ansi-styles-2.2.1.tgz#b432dd3358b634cf75e1e4664368240533c1ddbe"
+
+ansi-styles@^3.1.0:
+  version "3.2.0"
+  resolved "https://registry.yarnpkg.com/ansi-styles/-/ansi-styles-3.2.0.tgz#c159b8d5be0f9e5a6f346dab94f16ce022161b88"
+  dependencies:
+    color-convert "^1.9.0"
+
+anymatch@^1.3.0:
+  version "1.3.0"
+  resolved "https://registry.yarnpkg.com/anymatch/-/anymatch-1.3.0.tgz#a3e52fa39168c825ff57b0248126ce5a8ff95507"
+  dependencies:
+    arrify "^1.0.0"
+    micromatch "^2.1.5"
+
+aproba@^1.0.3:
+  version "1.1.2"
+  resolved "https://registry.yarnpkg.com/aproba/-/aproba-1.1.2.tgz#45c6629094de4e96f693ef7eab74ae079c240fc1"
+
+are-we-there-yet@~1.1.2:
+  version "1.1.4"
+  resolved "https://registry.yarnpkg.com/are-we-there-yet/-/are-we-there-yet-1.1.4.tgz#bb5dca382bb94f05e15194373d16fd3ba1ca110d"
+  dependencies:
+    delegates "^1.0.0"
+    readable-stream "^2.0.6"
+
+argparse@^1.0.7:
+  version "1.0.9"
+  resolved "https://registry.yarnpkg.com/argparse/-/argparse-1.0.9.tgz#73d83bc263f86e97f8cc4f6bae1b0e90a7d22c86"
+  dependencies:
+    sprintf-js "~1.0.2"
+
+arr-diff@^2.0.0:
+  version "2.0.0"
+  resolved "https://registry.yarnpkg.com/arr-diff/-/arr-diff-2.0.0.tgz#8f3b827f955a8bd669697e4a4256ac3ceae356cf"
+  dependencies:
+    arr-flatten "^1.0.1"
+
+arr-flatten@^1.0.1:
+  version "1.1.0"
+  resolved "https://registry.yarnpkg.com/arr-flatten/-/arr-flatten-1.1.0.tgz#36048bbff4e7b47e136644316c99669ea5ae91f1"
+
+array-union@^1.0.1:
+  version "1.0.2"
+  resolved "https://registry.yarnpkg.com/array-union/-/array-union-1.0.2.tgz#9a34410e4f4e3da23dea375be5be70f24778ec39"
+  dependencies:
+    array-uniq "^1.0.1"
+
+array-uniq@^1.0.1:
+  version "1.0.3"
+  resolved "https://registry.yarnpkg.com/array-uniq/-/array-uniq-1.0.3.tgz#af6ac877a25cc7f74e058894753858dfdb24fdb6"
+
+array-unique@^0.2.1:
+  version "0.2.1"
+  resolved "https://registry.yarnpkg.com/array-unique/-/array-unique-0.2.1.tgz#a1d97ccafcbc2625cc70fadceb36a50c58b01a53"
+
+arrify@^1.0.0:
+  version "1.0.1"
+  resolved "https://registry.yarnpkg.com/arrify/-/arrify-1.0.1.tgz#898508da2226f380df904728456849c1501a4b0d"
+
+asn1.js@^4.0.0:
+  version "4.9.1"
+  resolved "https://registry.yarnpkg.com/asn1.js/-/asn1.js-4.9.1.tgz#48ba240b45a9280e94748990ba597d216617fd40"
+  dependencies:
+    bn.js "^4.0.0"
+    inherits "^2.0.1"
+    minimalistic-assert "^1.0.0"
+
+asn1@~0.2.3:
+  version "0.2.3"
+  resolved "https://registry.yarnpkg.com/asn1/-/asn1-0.2.3.tgz#dac8787713c9966849fc8180777ebe9c1ddf3b86"
+
+assert-plus@1.0.0, assert-plus@^1.0.0:
+  version "1.0.0"
+  resolved "https://registry.yarnpkg.com/assert-plus/-/assert-plus-1.0.0.tgz#f12e0f3c5d77b0b1cdd9146942e4e96c1e4dd525"
+
+assert-plus@^0.2.0:
+  version "0.2.0"
+  resolved "https://registry.yarnpkg.com/assert-plus/-/assert-plus-0.2.0.tgz#d74e1b87e7affc0db8aadb7021f3fe48101ab234"
+
+assert@^1.1.1:
+  version "1.4.1"
+  resolved "https://registry.yarnpkg.com/assert/-/assert-1.4.1.tgz#99912d591836b5a6f5b345c0f07eefc08fc65d91"
+  dependencies:
+    util "0.10.3"
+
+async-each@^1.0.0:
+  version "1.0.1"
+  resolved "https://registry.yarnpkg.com/async-each/-/async-each-1.0.1.tgz#19d386a1d9edc6e7c1c85d388aedbcc56d33602d"
+
+async@^2.1.2:
+  version "2.5.0"
+  resolved "https://registry.yarnpkg.com/async/-/async-2.5.0.tgz#843190fd6b7357a0b9e1c956edddd5ec8462b54d"
+  dependencies:
+    lodash "^4.14.0"
+
+asynckit@^0.4.0:
+  version "0.4.0"
+  resolved "https://registry.yarnpkg.com/asynckit/-/asynckit-0.4.0.tgz#c79ed97f7f34cb8f2ba1bc9790bcc366474b4b79"
+
+aws-sign2@~0.6.0:
+  version "0.6.0"
+  resolved "https://registry.yarnpkg.com/aws-sign2/-/aws-sign2-0.6.0.tgz#14342dd38dbcc94d0e5b87d763cd63612c0e794f"
+
+aws4@^1.2.1:
+  version "1.6.0"
+  resolved "https://registry.yarnpkg.com/aws4/-/aws4-1.6.0.tgz#83ef5ca860b2b32e4a0deedee8c771b9db57471e"
+
+babel-code-frame@^6.22.0:
+  version "6.22.0"
+  resolved "https://registry.yarnpkg.com/babel-code-frame/-/babel-code-frame-6.22.0.tgz#027620bee567a88c32561574e7fd0801d33118e4"
+  dependencies:
+    chalk "^1.1.0"
+    esutils "^2.0.2"
+    js-tokens "^3.0.0"
+
+babel-core@^6.24.1, babel-core@^6.25.0:
+  version "6.25.0"
+  resolved "https://registry.yarnpkg.com/babel-core/-/babel-core-6.25.0.tgz#7dd42b0463c742e9d5296deb3ec67a9322dad729"
+  dependencies:
+    babel-code-frame "^6.22.0"
+    babel-generator "^6.25.0"
+    babel-helpers "^6.24.1"
+    babel-messages "^6.23.0"
+    babel-register "^6.24.1"
+    babel-runtime "^6.22.0"
+    babel-template "^6.25.0"
+    babel-traverse "^6.25.0"
+    babel-types "^6.25.0"
+    babylon "^6.17.2"
+    convert-source-map "^1.1.0"
+    debug "^2.1.1"
+    json5 "^0.5.0"
+    lodash "^4.2.0"
+    minimatch "^3.0.2"
+    path-is-absolute "^1.0.0"
+    private "^0.1.6"
+    slash "^1.0.0"
+    source-map "^0.5.0"
+
+babel-generator@^6.25.0:
+  version "6.25.0"
+  resolved "https://registry.yarnpkg.com/babel-generator/-/babel-generator-6.25.0.tgz#33a1af70d5f2890aeb465a4a7793c1df6a9ea9fc"
+  dependencies:
+    babel-messages "^6.23.0"
+    babel-runtime "^6.22.0"
+    babel-types "^6.25.0"
+    detect-indent "^4.0.0"
+    jsesc "^1.3.0"
+    lodash "^4.2.0"
+    source-map "^0.5.0"
+    trim-right "^1.0.1"
+
+babel-helper-builder-binary-assignment-operator-visitor@^6.24.1:
+  version "6.24.1"
+  resolved "https://registry.yarnpkg.com/babel-helper-builder-binary-assignment-operator-visitor/-/babel-helper-builder-binary-assignment-operator-visitor-6.24.1.tgz#cce4517ada356f4220bcae8a02c2b346f9a56664"
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+    babel-types "^6.25.0"
+    babylon "^6.17.2"
+    debug "^2.2.0"
+    globals "^9.0.0"
+    invariant "^2.2.0"
+    lodash "^4.2.0"
+
+babel-types@^6.19.0, babel-types@^6.24.1, babel-types@^6.25.0:
+  version "6.25.0"
+  resolved "https://registry.yarnpkg.com/babel-types/-/babel-types-6.25.0.tgz#70afb248d5660e5d18f811d91c8303b54134a18e"
+  dependencies:
+    babel-runtime "^6.22.0"
+    esutils "^2.0.2"
+    lodash "^4.2.0"
+    to-fast-properties "^1.0.1"
+
+babylon@^6.17.2:
+  version "6.17.4"
+  resolved "https://registry.yarnpkg.com/babylon/-/babylon-6.17.4.tgz#3e8b7402b88d22c3423e137a1577883b15ff869a"
+
+balanced-match@^1.0.0:
+  version "1.0.0"
+  resolved "https://registry.yarnpkg.com/balanced-match/-/balanced-match-1.0.0.tgz#89b4d199ab2bee49de164ea02b89ce462d71b767"
+
+base64-js@^1.0.2:
+  version "1.2.1"
+  resolved "https://registry.yarnpkg.com/base64-js/-/base64-js-1.2.1.tgz#a91947da1f4a516ea38e5b4ec0ec3773675e0886"
+
+bcrypt-pbkdf@^1.0.0:
+  version "1.0.1"
+  resolved "https://registry.yarnpkg.com/bcrypt-pbkdf/-/bcrypt-pbkdf-1.0.1.tgz#63bc5dcb61331b92bc05fd528953c33462a06f8d"
+  dependencies:
+    tweetnacl "^0.14.3"
+
+big.js@^3.1.3:
+  version "3.1.3"
+  resolved "https://registry.yarnpkg.com/big.js/-/big.js-3.1.3.tgz#4cada2193652eb3ca9ec8e55c9015669c9806978"
+
+binary-extensions@^1.0.0:
+  version "1.9.0"
+  resolved "https://registry.yarnpkg.com/binary-extensions/-/binary-extensions-1.9.0.tgz#66506c16ce6f4d6928a5b3cd6a33ca41e941e37b"
+
+block-stream@*:
+  version "0.0.9"
+  resolved "https://registry.yarnpkg.com/block-stream/-/block-stream-0.0.9.tgz#13ebfe778a03205cfe03751481ebb4b3300c126a"
+  dependencies:
+    inherits "~2.0.0"
+
+bn.js@^4.0.0, bn.js@^4.1.0, bn.js@^4.1.1, bn.js@^4.4.0:
+  version "4.11.7"
+  resolved "https://registry.yarnpkg.com/bn.js/-/bn.js-4.11.7.tgz#ddb048e50d9482790094c13eb3fcfc833ce7ab46"
+
+boom@2.x.x:
+  version "2.10.1"
+  resolved "https://registry.yarnpkg.com/boom/-/boom-2.10.1.tgz#39c8918ceff5799f83f9492a848f625add0c766f"
+  dependencies:
+    hoek "2.x.x"
+
+brace-expansion@^1.1.7:
+  version "1.1.8"
+  resolved "https://registry.yarnpkg.com/brace-expansion/-/brace-expansion-1.1.8.tgz#c07b211c7c952ec1f8efd51a77ef0d1d3990a292"
+  dependencies:
+    balanced-match "^1.0.0"
+    concat-map "0.0.1"
+
+braces@^1.8.2:
+  version "1.8.5"
+  resolved "https://registry.yarnpkg.com/braces/-/braces-1.8.5.tgz#ba77962e12dff969d6b76711e914b737857bf6a7"
+  dependencies:
+    expand-range "^1.8.1"
+    preserve "^0.2.0"
+    repeat-element "^1.1.2"
+
+brorand@^1.0.1:
+  version "1.1.0"
+  resolved "https://registry.yarnpkg.com/brorand/-/brorand-1.1.0.tgz#12c25efe40a45e3c323eb8675a0a0ce57b22371f"
+
+browserify-aes@^1.0.0, browserify-aes@^1.0.4:
+  version "1.0.6"
+  resolved "https://registry.yarnpkg.com/browserify-aes/-/browserify-aes-1.0.6.tgz#5e7725dbdef1fd5930d4ebab48567ce451c48a0a"
+  dependencies:
+    buffer-xor "^1.0.2"
+    cipher-base "^1.0.0"
+    create-hash "^1.1.0"
+    evp_bytestokey "^1.0.0"
+    inherits "^2.0.1"
+
+browserify-cipher@^1.0.0:
+  version "1.0.0"
+  resolved "https://registry.yarnpkg.com/browserify-cipher/-/browserify-cipher-1.0.0.tgz#9988244874bf5ed4e28da95666dcd66ac8fc363a"
+  dependencies:
+    browserify-aes "^1.0.4"
+    browserify-des "^1.0.0"
+    evp_bytestokey "^1.0.0"
+
+browserify-des@^1.0.0:
+  version "1.0.0"
+  resolved "https://registry.yarnpkg.com/browserify-des/-/browserify-des-1.0.0.tgz#daa277717470922ed2fe18594118a175439721dd"
+  dependencies:
+    cipher-base "^1.0.1"
+    des.js "^1.0.0"
+    inherits "^2.0.1"
+
+browserify-rsa@^4.0.0:
+  version "4.0.1"
+  resolved "https://registry.yarnpkg.com/browserify-rsa/-/browserify-rsa-4.0.1.tgz#21e0abfaf6f2029cf2fafb133567a701d4135524"
+  dependencies:
+    bn.js "^4.1.0"
+    randombytes "^2.0.1"
+
+browserify-sign@^4.0.0:
+  version "4.0.4"
+  resolved "https://registry.yarnpkg.com/browserify-sign/-/browserify-sign-4.0.4.tgz#aa4eb68e5d7b658baa6bf6a57e630cbd7a93d298"
+  dependencies:
+    bn.js "^4.1.1"
+    browserify-rsa "^4.0.0"
+    create-hash "^1.1.0"
+    create-hmac "^1.1.2"
+    elliptic "^6.0.0"
+    inherits "^2.0.1"
+    parse-asn1 "^5.0.0"
+
+browserify-zlib@^0.1.4:
+  version "0.1.4"
+  resolved "https://registry.yarnpkg.com/browserify-zlib/-/browserify-zlib-0.1.4.tgz#bb35f8a519f600e0fa6b8485241c979d0141fb2d"
+  dependencies:
+    pako "~0.2.0"
+
+browserslist@^2.1.2:
+  version "2.2.2"
+  resolved "https://registry.yarnpkg.com/browserslist/-/browserslist-2.2.2.tgz#e9b4618b8a01c193f9786beea09f6fd10dbe31c3"
+  dependencies:
+    caniuse-lite "^1.0.30000704"
+    electron-to-chromium "^1.3.16"
+
+buffer-xor@^1.0.2:
+  version "1.0.3"
+  resolved "https://registry.yarnpkg.com/buffer-xor/-/buffer-xor-1.0.3.tgz#26e61ed1422fb70dd42e6e36729ed51d855fe8d9"
+
+buffer@^4.3.0:
+  version "4.9.1"
+  resolved "https://registry.yarnpkg.com/buffer/-/buffer-4.9.1.tgz#6d1bb601b07a4efced97094132093027c95bc298"
+  dependencies:
+    base64-js "^1.0.2"
+    ieee754 "^1.1.4"
+    isarray "^1.0.0"
+
+builtin-modules@^1.0.0, builtin-modules@^1.1.1:
+  version "1.1.1"
+  resolved "https://registry.yarnpkg.com/builtin-modules/-/builtin-modules-1.1.1.tgz#270f076c5a72c02f5b65a47df94c5fe3a278892f"
+
+builtin-status-codes@^3.0.0:
+  version "3.0.0"
+  resolved "https://registry.yarnpkg.com/builtin-status-codes/-/builtin-status-codes-3.0.0.tgz#85982878e21b98e1c66425e03d0174788f569ee8"
+
+caller-path@^0.1.0:
+  version "0.1.0"
+  resolved "https://registry.yarnpkg.com/caller-path/-/caller-path-0.1.0.tgz#94085ef63581ecd3daa92444a8fe94e82577751f"
+  dependencies:
+    callsites "^0.2.0"
+
+callsites@^0.2.0:
+  version "0.2.0"
+  resolved "https://registry.yarnpkg.com/callsites/-/callsites-0.2.0.tgz#afab96262910a7f33c19a5775825c69f34e350ca"
+
+camelcase@^1.0.2:
+  version "1.2.1"
+  resolved "https://registry.yarnpkg.com/camelcase/-/camelcase-1.2.1.tgz#9bb5304d2e0b56698b2c758b08a3eaa9daa58a39"
+
+camelcase@^4.1.0:
+  version "4.1.0"
+  resolved "https://registry.yarnpkg.com/camelcase/-/camelcase-4.1.0.tgz#d545635be1e33c542649c69173e5de6acfae34dd"
+
+caniuse-lite@^1.0.30000704:
+  version "1.0.30000706"
+  resolved "https://registry.yarnpkg.com/caniuse-lite/-/caniuse-lite-1.0.30000706.tgz#bc59abc41ba7d4a3634dda95befded6114e1f24e"
+
+caseless@~0.12.0:
+  version "0.12.0"
+  resolved "https://registry.yarnpkg.com/caseless/-/caseless-0.12.0.tgz#1b681c21ff84033c826543090689420d187151dc"
+
+center-align@^0.1.1:
+  version "0.1.3"
+  resolved "https://registry.yarnpkg.com/center-align/-/center-align-0.1.3.tgz#aa0d32629b6ee972200411cbd4461c907bc2b7ad"
+  dependencies:
+    align-text "^0.1.3"
+    lazy-cache "^1.0.3"
+
+chalk@^1.1.0, chalk@^1.1.1, chalk@^1.1.3:
+  version "1.1.3"
+  resolved "https://registry.yarnpkg.com/chalk/-/chalk-1.1.3.tgz#a8115c55e4a702fe4d150abd3872822a7e09fc98"
+  dependencies:
+    ansi-styles "^2.2.1"
+    escape-string-regexp "^1.0.2"
+    has-ansi "^2.0.0"
+    strip-ansi "^3.0.0"
+    supports-color "^2.0.0"
+
+chalk@^2.0.0:
+  version "2.0.1"
+  resolved "https://registry.yarnpkg.com/chalk/-/chalk-2.0.1.tgz#dbec49436d2ae15f536114e76d14656cdbc0f44d"
+  dependencies:
+    ansi-styles "^3.1.0"
+    escape-string-regexp "^1.0.5"
+    supports-color "^4.0.0"
+
+chokidar@^1.7.0:
+  version "1.7.0"
+  resolved "https://registry.yarnpkg.com/chokidar/-/chokidar-1.7.0.tgz#798e689778151c8076b4b360e5edd28cda2bb468"
+  dependencies:
+    anymatch "^1.3.0"
+    async-each "^1.0.0"
+    glob-parent "^2.0.0"
+    inherits "^2.0.1"
+    is-binary-path "^1.0.0"
+    is-glob "^2.0.0"
+    path-is-absolute "^1.0.0"
+    readdirp "^2.0.0"
+  optionalDependencies:
+    fsevents "^1.0.0"
+
+cipher-base@^1.0.0, cipher-base@^1.0.1, cipher-base@^1.0.3:
+  version "1.0.4"
+  resolved "https://registry.yarnpkg.com/cipher-base/-/cipher-base-1.0.4.tgz#8760e4ecc272f4c363532f926d874aae2c1397de"
+  dependencies:
+    inherits "^2.0.1"
+    safe-buffer "^5.0.1"
+
+circular-json@^0.3.1:
+  version "0.3.3"
+  resolved "https://registry.yarnpkg.com/circular-json/-/circular-json-0.3.3.tgz#815c99ea84f6809529d2f45791bdf82711352d66"
+
+cli-cursor@^2.1.0:
+  version "2.1.0"
+  resolved "https://registry.yarnpkg.com/cli-cursor/-/cli-cursor-2.1.0.tgz#b35dac376479facc3e94747d41d0d0f5238ffcb5"
+  dependencies:
+    restore-cursor "^2.0.0"
+
+cli-width@^2.0.0:
+  version "2.1.0"
+  resolved "https://registry.yarnpkg.com/cli-width/-/cli-width-2.1.0.tgz#b234ca209b29ef66fc518d9b98d5847b00edf00a"
+
+cliui@^2.1.0:
+  version "2.1.0"
+  resolved "https://registry.yarnpkg.com/cliui/-/cliui-2.1.0.tgz#4b475760ff80264c762c3a1719032e91c7fea0d1"
+  dependencies:
+    center-align "^0.1.1"
+    right-align "^0.1.1"
+    wordwrap "0.0.2"
+
+cliui@^3.2.0:
+  version "3.2.0"
+  resolved "https://registry.yarnpkg.com/cliui/-/cliui-3.2.0.tgz#120601537a916d29940f934da3b48d585a39213d"
+  dependencies:
+    string-width "^1.0.1"
+    strip-ansi "^3.0.1"
+    wrap-ansi "^2.0.0"
+
+co@^4.6.0:
+  version "4.6.0"
+  resolved "https://registry.yarnpkg.com/co/-/co-4.6.0.tgz#6ea6bdf3d853ae54ccb8e47bfa0bf3f9031fb184"
+
+code-point-at@^1.0.0:
+  version "1.1.0"
+  resolved "https://registry.yarnpkg.com/code-point-at/-/code-point-at-1.1.0.tgz#0d070b4d043a5bea33a2f1a40e2edb3d9a4ccf77"
+
+color-convert@^1.9.0:
+  version "1.9.0"
+  resolved "https://registry.yarnpkg.com/color-convert/-/color-convert-1.9.0.tgz#1accf97dd739b983bf994d56fec8f95853641b7a"
+  dependencies:
+    color-name "^1.1.1"
+
+color-name@^1.1.1:
+  version "1.1.3"
+  resolved "https://registry.yarnpkg.com/color-name/-/color-name-1.1.3.tgz#a7d0558bd89c42f795dd42328f740831ca53bc25"
+
+combined-stream@^1.0.5, combined-stream@~1.0.5:
+  version "1.0.5"
+  resolved "https://registry.yarnpkg.com/combined-stream/-/combined-stream-1.0.5.tgz#938370a57b4a51dea2c77c15d5c5fdf895164009"
+  dependencies:
+    delayed-stream "~1.0.0"
+
+commondir@^1.0.1:
+  version "1.0.1"
+  resolved "https://registry.yarnpkg.com/commondir/-/commondir-1.0.1.tgz#ddd800da0c66127393cca5950ea968a3aaf1253b"
+
+concat-map@0.0.1:
+  version "0.0.1"
+  resolved "https://registry.yarnpkg.com/concat-map/-/concat-map-0.0.1.tgz#d8a96bd77fd68df7793a73036a3ba0d5405d477b"
+
+concat-stream@^1.6.0:
+  version "1.6.0"
+  resolved "https://registry.yarnpkg.com/concat-stream/-/concat-stream-1.6.0.tgz#0aac662fd52be78964d5532f694784e70110acf7"
+  dependencies:
+    inherits "^2.0.3"
+    readable-stream "^2.2.2"
+    typedarray "^0.0.6"
+
+console-browserify@^1.1.0:
+  version "1.1.0"
+  resolved "https://registry.yarnpkg.com/console-browserify/-/console-browserify-1.1.0.tgz#f0241c45730a9fc6323b206dbf38edc741d0bb10"
+  dependencies:
+    date-now "^0.1.4"
+
+console-control-strings@^1.0.0, console-control-strings@~1.1.0:
+  version "1.1.0"
+  resolved "https://registry.yarnpkg.com/console-control-strings/-/console-control-strings-1.1.0.tgz#3d7cf4464db6446ea644bf4b39507f9851008e8e"
+
+constants-browserify@^1.0.0:
+  version "1.0.0"
+  resolved "https://registry.yarnpkg.com/constants-browserify/-/constants-browserify-1.0.0.tgz#c20b96d8c617748aaf1c16021760cd27fcb8cb75"
+
+contains-path@^0.1.0:
+  version "0.1.0"
+  resolved "https://registry.yarnpkg.com/contains-path/-/contains-path-0.1.0.tgz#fe8cf184ff6670b6baef01a9d4861a5cbec4120a"
+
+convert-source-map@^1.1.0:
+  version "1.5.0"
+  resolved "https://registry.yarnpkg.com/convert-source-map/-/convert-source-map-1.5.0.tgz#9acd70851c6d5dfdd93d9282e5edf94a03ff46b5"
+
+core-js@^2.4.0:
+  version "2.4.1"
+  resolved "https://registry.yarnpkg.com/core-js/-/core-js-2.4.1.tgz#4de911e667b0eae9124e34254b53aea6fc618d3e"
+
+core-util-is@~1.0.0:
+  version "1.0.2"
+  resolved "https://registry.yarnpkg.com/core-util-is/-/core-util-is-1.0.2.tgz#b5fd54220aa2bc5ab57aab7140c940754503c1a7"
+
+create-ecdh@^4.0.0:
+  version "4.0.0"
+  resolved "https://registry.yarnpkg.com/create-ecdh/-/create-ecdh-4.0.0.tgz#888c723596cdf7612f6498233eebd7a35301737d"
+  dependencies:
+    bn.js "^4.1.0"
+    elliptic "^6.0.0"
+
+create-hash@^1.1.0, create-hash@^1.1.1, create-hash@^1.1.2:
+  version "1.1.3"
+  resolved "https://registry.yarnpkg.com/create-hash/-/create-hash-1.1.3.tgz#606042ac8b9262750f483caddab0f5819172d8fd"
+  dependencies:
+    cipher-base "^1.0.1"
+    inherits "^2.0.1"
+    ripemd160 "^2.0.0"
+    sha.js "^2.4.0"
+
+create-hmac@^1.1.0, create-hmac@^1.1.2, create-hmac@^1.1.4:
+  version "1.1.6"
+  resolved "https://registry.yarnpkg.com/create-hmac/-/create-hmac-1.1.6.tgz#acb9e221a4e17bdb076e90657c42b93e3726cf06"
+  dependencies:
+    cipher-base "^1.0.3"
+    create-hash "^1.1.0"
+    inherits "^2.0.1"
+    ripemd160 "^2.0.0"
+    safe-buffer "^5.0.1"
+    sha.js "^2.4.8"
+
+cross-spawn@^5.0.1, cross-spawn@^5.1.0:
+  version "5.1.0"
+  resolved "https://registry.yarnpkg.com/cross-spawn/-/cross-spawn-5.1.0.tgz#e8bd0efee58fcff6f8f94510a0a554bbfa235449"
+  dependencies:
+    lru-cache "^4.0.1"
+    shebang-command "^1.2.0"
+    which "^1.2.9"
+
+cryptiles@2.x.x:
+  version "2.0.5"
+  resolved "https://registry.yarnpkg.com/cryptiles/-/cryptiles-2.0.5.tgz#3bdfecdc608147c1c67202fa291e7dca59eaa3b8"
+  dependencies:
+    boom "2.x.x"
+
+crypto-browserify@^3.11.0:
+  version "3.11.1"
+  resolved "https://registry.yarnpkg.com/crypto-browserify/-/crypto-browserify-3.11.1.tgz#948945efc6757a400d6e5e5af47194d10064279f"
+  dependencies:
+    browserify-cipher "^1.0.0"
+    browserify-sign "^4.0.0"
+    create-ecdh "^4.0.0"
+    create-hash "^1.1.0"
+    create-hmac "^1.1.0"
+    diffie-hellman "^5.0.0"
+    inherits "^2.0.1"
+    pbkdf2 "^3.0.3"
+    public-encrypt "^4.0.0"
+    randombytes "^2.0.0"
+
+d@1:
+  version "1.0.0"
+  resolved "https://registry.yarnpkg.com/d/-/d-1.0.0.tgz#754bb5bfe55451da69a58b94d45f4c5b0462d58f"
+  dependencies:
+    es5-ext "^0.10.9"
+
+dashdash@^1.12.0:
+  version "1.14.1"
+  resolved "https://registry.yarnpkg.com/dashdash/-/dashdash-1.14.1.tgz#853cfa0f7cbe2fed5de20326b8dd581035f6e2f0"
+  dependencies:
+    assert-plus "^1.0.0"
+
+date-now@^0.1.4:
+  version "0.1.4"
+  resolved "https://registry.yarnpkg.com/date-now/-/date-now-0.1.4.tgz#eaf439fd4d4848ad74e5cc7dbef200672b9e345b"
+
+debug@^2.1.1, debug@^2.2.0, debug@^2.6.8:
+  version "2.6.8"
+  resolved "https://registry.yarnpkg.com/debug/-/debug-2.6.8.tgz#e731531ca2ede27d188222427da17821d68ff4fc"
+  dependencies:
+    ms "2.0.0"
+
+decamelize@^1.0.0, decamelize@^1.1.1:
+  version "1.2.0"
+  resolved "https://registry.yarnpkg.com/decamelize/-/decamelize-1.2.0.tgz#f6534d15148269b20352e7bee26f501f9a191290"
+
+deep-extend@~0.4.0:
+  version "0.4.2"
+  resolved "https://registry.yarnpkg.com/deep-extend/-/deep-extend-0.4.2.tgz#48b699c27e334bf89f10892be432f6e4c7d34a7f"
+
+deep-is@~0.1.3:
+  version "0.1.3"
+  resolved "https://registry.yarnpkg.com/deep-is/-/deep-is-0.1.3.tgz#b369d6fb5dbc13eecf524f91b070feedc357cf34"
+
+del@^2.0.2:
+  version "2.2.2"
+  resolved "https://registry.yarnpkg.com/del/-/del-2.2.2.tgz#c12c981d067846c84bcaf862cff930d907ffd1a8"
+  dependencies:
+    globby "^5.0.0"
+    is-path-cwd "^1.0.0"
+    is-path-in-cwd "^1.0.0"
+    object-assign "^4.0.1"
+    pify "^2.0.0"
+    pinkie-promise "^2.0.0"
+    rimraf "^2.2.8"
+
+delayed-stream@~1.0.0:
+  version "1.0.0"
+  resolved "https://registry.yarnpkg.com/delayed-stream/-/delayed-stream-1.0.0.tgz#df3ae199acadfb7d440aaae0b29e2272b24ec619"
+
+delegates@^1.0.0:
+  version "1.0.0"
+  resolved "https://registry.yarnpkg.com/delegates/-/delegates-1.0.0.tgz#84c6e159b81904fdca59a0ef44cd870d31250f9a"
+
+des.js@^1.0.0:
+  version "1.0.0"
+  resolved "https://registry.yarnpkg.com/des.js/-/des.js-1.0.0.tgz#c074d2e2aa6a8a9a07dbd61f9a15c2cd83ec8ecc"
+  dependencies:
+    inherits "^2.0.1"
+    minimalistic-assert "^1.0.0"
+
+detect-indent@^4.0.0:
+  version "4.0.0"
+  resolved "https://registry.yarnpkg.com/detect-indent/-/detect-indent-4.0.0.tgz#f76d064352cdf43a1cb6ce619c4ee3a9475de208"
+  dependencies:
+    repeating "^2.0.0"
+
+diffie-hellman@^5.0.0:
+  version "5.0.2"
+  resolved "https://registry.yarnpkg.com/diffie-hellman/-/diffie-hellman-5.0.2.tgz#b5835739270cfe26acf632099fded2a07f209e5e"
+  dependencies:
+    bn.js "^4.1.0"
+    miller-rabin "^4.0.0"
+    randombytes "^2.0.0"
+
+doctrine@1.5.0:
+  version "1.5.0"
+  resolved "https://registry.yarnpkg.com/doctrine/-/doctrine-1.5.0.tgz#379dce730f6166f76cefa4e6707a159b02c5a6fa"
+  dependencies:
+    esutils "^2.0.2"
+    isarray "^1.0.0"
+
+doctrine@^2.0.0:
+  version "2.0.0"
+  resolved "https://registry.yarnpkg.com/doctrine/-/doctrine-2.0.0.tgz#c73d8d2909d22291e1a007a395804da8b665fe63"
+  dependencies:
+    esutils "^2.0.2"
+    isarray "^1.0.0"
+
+domain-browser@^1.1.1:
+  version "1.1.7"
+  resolved "https://registry.yarnpkg.com/domain-browser/-/domain-browser-1.1.7.tgz#867aa4b093faa05f1de08c06f4d7b21fdf8698bc"
+
+ecc-jsbn@~0.1.1:
+  version "0.1.1"
+  resolved "https://registry.yarnpkg.com/ecc-jsbn/-/ecc-jsbn-0.1.1.tgz#0fc73a9ed5f0d53c38193398523ef7e543777505"
+  dependencies:
+    jsbn "~0.1.0"
+
+electron-to-chromium@^1.3.16:
+  version "1.3.16"
+  resolved "https://registry.yarnpkg.com/electron-to-chromium/-/electron-to-chromium-1.3.16.tgz#d0e026735754770901ae301a21664cba45d92f7d"
+
+elliptic@^6.0.0:
+  version "6.4.0"
+  resolved "https://registry.yarnpkg.com/elliptic/-/elliptic-6.4.0.tgz#cac9af8762c85836187003c8dfe193e5e2eae5df"
+  dependencies:
+    bn.js "^4.4.0"
+    brorand "^1.0.1"
+    hash.js "^1.0.0"
+    hmac-drbg "^1.0.0"
+    inherits "^2.0.1"
+    minimalistic-assert "^1.0.0"
+    minimalistic-crypto-utils "^1.0.0"
+
+emojis-list@^2.0.0:
+  version "2.1.0"
+  resolved "https://registry.yarnpkg.com/emojis-list/-/emojis-list-2.1.0.tgz#4daa4d9db00f9819880c79fa457ae5b09a1fd389"
+
+enhanced-resolve@^3.4.0:
+  version "3.4.1"
+  resolved "https://registry.yarnpkg.com/enhanced-resolve/-/enhanced-resolve-3.4.1.tgz#0421e339fd71419b3da13d129b3979040230476e"
+  dependencies:
+    graceful-fs "^4.1.2"
+    memory-fs "^0.4.0"
+    object-assign "^4.0.1"
+    tapable "^0.2.7"
+
+errno@^0.1.3:
+  version "0.1.4"
+  resolved "https://registry.yarnpkg.com/errno/-/errno-0.1.4.tgz#b896e23a9e5e8ba33871fc996abd3635fc9a1c7d"
+  dependencies:
+    prr "~0.0.0"
+
+error-ex@^1.2.0:
+  version "1.3.1"
+  resolved "https://registry.yarnpkg.com/error-ex/-/error-ex-1.3.1.tgz#f855a86ce61adc4e8621c3cda21e7a7612c3a8dc"
+  dependencies:
+    is-arrayish "^0.2.1"
+
+es5-ext@^0.10.14, es5-ext@^0.10.9, es5-ext@~0.10.14:
+  version "0.10.24"
+  resolved "https://registry.yarnpkg.com/es5-ext/-/es5-ext-0.10.24.tgz#a55877c9924bc0c8d9bd3c2cbe17495ac1709b14"
+  dependencies:
+    es6-iterator "2"
+    es6-symbol "~3.1"
+
+es6-iterator@2, es6-iterator@^2.0.1, es6-iterator@~2.0.1:
+  version "2.0.1"
+  resolved "https://registry.yarnpkg.com/es6-iterator/-/es6-iterator-2.0.1.tgz#8e319c9f0453bf575d374940a655920e59ca5512"
+  dependencies:
+    d "1"
+    es5-ext "^0.10.14"
+    es6-symbol "^3.1"
+
+es6-map@^0.1.3:
+  version "0.1.5"
+  resolved "https://registry.yarnpkg.com/es6-map/-/es6-map-0.1.5.tgz#9136e0503dcc06a301690f0bb14ff4e364e949f0"
+  dependencies:
+    d "1"
+    es5-ext "~0.10.14"
+    es6-iterator "~2.0.1"
+    es6-set "~0.1.5"
+    es6-symbol "~3.1.1"
+    event-emitter "~0.3.5"
+
+es6-set@~0.1.5:
+  version "0.1.5"
+  resolved "https://registry.yarnpkg.com/es6-set/-/es6-set-0.1.5.tgz#d2b3ec5d4d800ced818db538d28974db0a73ccb1"
+  dependencies:
+    d "1"
+    es5-ext "~0.10.14"
+    es6-iterator "~2.0.1"
+    es6-symbol "3.1.1"
+    event-emitter "~0.3.5"
+
+es6-symbol@3.1.1, es6-symbol@^3.1, es6-symbol@^3.1.1, es6-symbol@~3.1, es6-symbol@~3.1.1:
+  version "3.1.1"
+  resolved "https://registry.yarnpkg.com/es6-symbol/-/es6-symbol-3.1.1.tgz#bf00ef4fdab6ba1b46ecb7b629b4c7ed5715cc77"
+  dependencies:
+    d "1"
+    es5-ext "~0.10.14"
+
+es6-weak-map@^2.0.1:
+  version "2.0.2"
+  resolved "https://registry.yarnpkg.com/es6-weak-map/-/es6-weak-map-2.0.2.tgz#5e3ab32251ffd1538a1f8e5ffa1357772f92d96f"
+  dependencies:
+    d "1"
+    es5-ext "^0.10.14"
+    es6-iterator "^2.0.1"
+    es6-symbol "^3.1.1"
+
+escape-string-regexp@^1.0.2, escape-string-regexp@^1.0.5:
+  version "1.0.5"
+  resolved "https://registry.yarnpkg.com/escape-string-regexp/-/escape-string-regexp-1.0.5.tgz#1b61c0562190a8dff6ae3bb2cf0200ca130b86d4"
+
+escope@^3.6.0:
+  version "3.6.0"
+  resolved "https://registry.yarnpkg.com/escope/-/escope-3.6.0.tgz#e01975e812781a163a6dadfdd80398dc64c889c3"
+  dependencies:
+    es6-map "^0.1.3"
+    es6-weak-map "^2.0.1"
+    esrecurse "^4.1.0"
+    estraverse "^4.1.1"
+
+eslint-import-resolver-node@^0.3.1:
+  version "0.3.1"
+  resolved "https://registry.yarnpkg.com/eslint-import-resolver-node/-/eslint-import-resolver-node-0.3.1.tgz#4422574cde66a9a7b099938ee4d508a199e0e3cc"
+  dependencies:
+    debug "^2.6.8"
+    resolve "^1.2.0"
+
+eslint-module-utils@^2.1.1:
+  version "2.1.1"
+  resolved "https://registry.yarnpkg.com/eslint-module-utils/-/eslint-module-utils-2.1.1.tgz#abaec824177613b8a95b299639e1b6facf473449"
+  dependencies:
+    debug "^2.6.8"
+    pkg-dir "^1.0.0"
+
+eslint-plugin-import@^2.7.0:
+  version "2.7.0"
+  resolved "https://registry.yarnpkg.com/eslint-plugin-import/-/eslint-plugin-import-2.7.0.tgz#21de33380b9efb55f5ef6d2e210ec0e07e7fa69f"
+  dependencies:
+    builtin-modules "^1.1.1"
+    contains-path "^0.1.0"
+    debug "^2.6.8"
+    doctrine "1.5.0"
+    eslint-import-resolver-node "^0.3.1"
+    eslint-module-utils "^2.1.1"
+    has "^1.0.1"
+    lodash.cond "^4.3.0"
+    minimatch "^3.0.3"
+    read-pkg-up "^2.0.0"
+
+eslint-scope@^3.7.1:
+  version "3.7.1"
+  resolved "https://registry.yarnpkg.com/eslint-scope/-/eslint-scope-3.7.1.tgz#3d63c3edfda02e06e01a452ad88caacc7cdcb6e8"
+  dependencies:
+    esrecurse "^4.1.0"
+    estraverse "^4.1.1"
+
+eslint@^4.3.0:
+  version "4.3.0"
+  resolved "https://registry.yarnpkg.com/eslint/-/eslint-4.3.0.tgz#fcd7c96376bbf34c85ee67ed0012a299642b108f"
+  dependencies:
+    ajv "^5.2.0"
+    babel-code-frame "^6.22.0"
+    chalk "^1.1.3"
+    concat-stream "^1.6.0"
+    cross-spawn "^5.1.0"
+    debug "^2.6.8"
+    doctrine "^2.0.0"
+    eslint-scope "^3.7.1"
+    espree "^3.4.3"
+    esquery "^1.0.0"
+    estraverse "^4.2.0"
+    esutils "^2.0.2"
+    file-entry-cache "^2.0.0"
+    functional-red-black-tree "^1.0.1"
+    glob "^7.1.2"
+    globals "^9.17.0"
+    ignore "^3.3.3"
+    imurmurhash "^0.1.4"
+    inquirer "^3.0.6"
+    is-resolvable "^1.0.0"
+    js-yaml "^3.8.4"
+    json-stable-stringify "^1.0.1"
+    levn "^0.3.0"
+    lodash "^4.17.4"
+    minimatch "^3.0.2"
+    mkdirp "^0.5.1"
+    natural-compare "^1.4.0"
+    optionator "^0.8.2"
+    path-is-inside "^1.0.2"
+    pluralize "^4.0.0"
+    progress "^2.0.0"
+    require-uncached "^1.0.3"
+    semver "^5.3.0"
+    strip-json-comments "~2.0.1"
+    table "^4.0.1"
+    text-table "~0.2.0"
+
+espree@^3.4.3:
+  version "3.4.3"
+  resolved "https://registry.yarnpkg.com/espree/-/espree-3.4.3.tgz#2910b5ccd49ce893c2ffffaab4fd8b3a31b82374"
+  dependencies:
+    acorn "^5.0.1"
+    acorn-jsx "^3.0.0"
+
+esprima@^4.0.0:
+  version "4.0.0"
+  resolved "https://registry.yarnpkg.com/esprima/-/esprima-4.0.0.tgz#4499eddcd1110e0b218bacf2fa7f7f59f55ca804"
+
+esquery@^1.0.0:
+  version "1.0.0"
+  resolved "https://registry.yarnpkg.com/esquery/-/esquery-1.0.0.tgz#cfba8b57d7fba93f17298a8a006a04cda13d80fa"
+  dependencies:
+    estraverse "^4.0.0"
+
+esrecurse@^4.1.0:
+  version "4.2.0"
+  resolved "https://registry.yarnpkg.com/esrecurse/-/esrecurse-4.2.0.tgz#fa9568d98d3823f9a41d91e902dcab9ea6e5b163"
+  dependencies:
+    estraverse "^4.1.0"
+    object-assign "^4.0.1"
+
+estraverse@^4.0.0, estraverse@^4.1.0, estraverse@^4.1.1, estraverse@^4.2.0:
+  version "4.2.0"
+  resolved "https://registry.yarnpkg.com/estraverse/-/estraverse-4.2.0.tgz#0dee3fed31fcd469618ce7342099fc1afa0bdb13"
+
+esutils@^2.0.2:
+  version "2.0.2"
+  resolved "https://registry.yarnpkg.com/esutils/-/esutils-2.0.2.tgz#0abf4f1caa5bcb1f7a9d8acc6dea4faaa04bac9b"
+
+event-emitter@~0.3.5:
+  version "0.3.5"
+  resolved "https://registry.yarnpkg.com/event-emitter/-/event-emitter-0.3.5.tgz#df8c69eef1647923c7157b9ce83840610b02cc39"
+  dependencies:
+    d "1"
+    es5-ext "~0.10.14"
+
+events@^1.0.0:
+  version "1.1.1"
+  resolved "https://registry.yarnpkg.com/events/-/events-1.1.1.tgz#9ebdb7635ad099c70dcc4c2a1f5004288e8bd924"
+
+evp_bytestokey@^1.0.0:
+  version "1.0.0"
+  resolved "https://registry.yarnpkg.com/evp_bytestokey/-/evp_bytestokey-1.0.0.tgz#497b66ad9fef65cd7c08a6180824ba1476b66e53"
+  dependencies:
+    create-hash "^1.1.1"
+
+execa@^0.7.0:
+  version "0.7.0"
+  resolved "https://registry.yarnpkg.com/execa/-/execa-0.7.0.tgz#944becd34cc41ee32a63a9faf27ad5a65fc59777"
+  dependencies:
+    cross-spawn "^5.0.1"
+    get-stream "^3.0.0"
+    is-stream "^1.1.0"
+    npm-run-path "^2.0.0"
+    p-finally "^1.0.0"
+    signal-exit "^3.0.0"
+    strip-eof "^1.0.0"
+
+expand-brackets@^0.1.4:
+  version "0.1.5"
+  resolved "https://registry.yarnpkg.com/expand-brackets/-/expand-brackets-0.1.5.tgz#df07284e342a807cd733ac5af72411e581d1177b"
+  dependencies:
+    is-posix-bracket "^0.1.0"
+
+expand-range@^1.8.1:
+  version "1.8.2"
+  resolved "https://registry.yarnpkg.com/expand-range/-/expand-range-1.8.2.tgz#a299effd335fe2721ebae8e257ec79644fc85337"
+  dependencies:
+    fill-range "^2.1.0"
+
+extend@~3.0.0:
+  version "3.0.1"
+  resolved "https://registry.yarnpkg.com/extend/-/extend-3.0.1.tgz#a755ea7bc1adfcc5a31ce7e762dbaadc5e636444"
+
+external-editor@^2.0.4:
+  version "2.0.4"
+  resolved "https://registry.yarnpkg.com/external-editor/-/external-editor-2.0.4.tgz#1ed9199da9cbfe2ef2f7a31b2fde8b0d12368972"
+  dependencies:
+    iconv-lite "^0.4.17"
+    jschardet "^1.4.2"
+    tmp "^0.0.31"
+
+extglob@^0.3.1:
+  version "0.3.2"
+  resolved "https://registry.yarnpkg.com/extglob/-/extglob-0.3.2.tgz#2e18ff3d2f49ab2765cec9023f011daa8d8349a1"
+  dependencies:
+    is-extglob "^1.0.0"
+
+extsprintf@1.0.2:
+  version "1.0.2"
+  resolved "https://registry.yarnpkg.com/extsprintf/-/extsprintf-1.0.2.tgz#e1080e0658e300b06294990cc70e1502235fd550"
+
+fast-deep-equal@^1.0.0:
+  version "1.0.0"
+  resolved "https://registry.yarnpkg.com/fast-deep-equal/-/fast-deep-equal-1.0.0.tgz#96256a3bc975595eb36d82e9929d060d893439ff"
+
+fast-levenshtein@~2.0.4:
+  version "2.0.6"
+  resolved "https://registry.yarnpkg.com/fast-levenshtein/-/fast-levenshtein-2.0.6.tgz#3d8a5c66883a16a30ca8643e851f19baa7797917"
+
+figures@^2.0.0:
+  version "2.0.0"
+  resolved "https://registry.yarnpkg.com/figures/-/figures-2.0.0.tgz#3ab1a2d2a62c8bfb431a0c94cb797a2fce27c962"
+  dependencies:
+    escape-string-regexp "^1.0.5"
+
+file-entry-cache@^2.0.0:
+  version "2.0.0"
+  resolved "https://registry.yarnpkg.com/file-entry-cache/-/file-entry-cache-2.0.0.tgz#c392990c3e684783d838b8c84a45d8a048458361"
+  dependencies:
+    flat-cache "^1.2.1"
+    object-assign "^4.0.1"
+
+filename-regex@^2.0.0:
+  version "2.0.1"
+  resolved "https://registry.yarnpkg.com/filename-regex/-/filename-regex-2.0.1.tgz#c1c4b9bee3e09725ddb106b75c1e301fe2f18b26"
+
+fill-range@^2.1.0:
+  version "2.2.3"
+  resolved "https://registry.yarnpkg.com/fill-range/-/fill-range-2.2.3.tgz#50b77dfd7e469bc7492470963699fe7a8485a723"
+  dependencies:
+    is-number "^2.1.0"
+    isobject "^2.0.0"
+    randomatic "^1.1.3"
+    repeat-element "^1.1.2"
+    repeat-string "^1.5.2"
+
+find-cache-dir@^1.0.0:
+  version "1.0.0"
+  resolved "https://registry.yarnpkg.com/find-cache-dir/-/find-cache-dir-1.0.0.tgz#9288e3e9e3cc3748717d39eade17cf71fc30ee6f"
+  dependencies:
+    commondir "^1.0.1"
+    make-dir "^1.0.0"
+    pkg-dir "^2.0.0"
+
+find-up@^1.0.0:
+  version "1.1.2"
+  resolved "https://registry.yarnpkg.com/find-up/-/find-up-1.1.2.tgz#6b2e9822b1a2ce0a60ab64d610eccad53cb24d0f"
+  dependencies:
+    path-exists "^2.0.0"
+    pinkie-promise "^2.0.0"
+
+find-up@^2.0.0, find-up@^2.1.0:
+  version "2.1.0"
+  resolved "https://registry.yarnpkg.com/find-up/-/find-up-2.1.0.tgz#45d1b7e506c717ddd482775a2b77920a3c0c57a7"
+  dependencies:
+    locate-path "^2.0.0"
+
+flat-cache@^1.2.1:
+  version "1.2.2"
+  resolved "https://registry.yarnpkg.com/flat-cache/-/flat-cache-1.2.2.tgz#fa86714e72c21db88601761ecf2f555d1abc6b96"
+  dependencies:
+    circular-json "^0.3.1"
+    del "^2.0.2"
+    graceful-fs "^4.1.2"
+    write "^0.2.1"
+
+for-in@^1.0.1:
+  version "1.0.2"
+  resolved "https://registry.yarnpkg.com/for-in/-/for-in-1.0.2.tgz#81068d295a8142ec0ac726c6e2200c30fb6d5e80"
+
+for-own@^0.1.4:
+  version "0.1.5"
+  resolved "https://registry.yarnpkg.com/for-own/-/for-own-0.1.5.tgz#5265c681a4f294dabbf17c9509b6763aa84510ce"
+  dependencies:
+    for-in "^1.0.1"
+
+forever-agent@~0.6.1:
+  version "0.6.1"
+  resolved "https://registry.yarnpkg.com/forever-agent/-/forever-agent-0.6.1.tgz#fbc71f0c41adeb37f96c577ad1ed42d8fdacca91"
+
+form-data@~2.1.1:
+  version "2.1.4"
+  resolved "https://registry.yarnpkg.com/form-data/-/form-data-2.1.4.tgz#33c183acf193276ecaa98143a69e94bfee1750d1"
+  dependencies:
+    asynckit "^0.4.0"
+    combined-stream "^1.0.5"
+    mime-types "^2.1.12"
+
+fs.realpath@^1.0.0:
+  version "1.0.0"
+  resolved "https://registry.yarnpkg.com/fs.realpath/-/fs.realpath-1.0.0.tgz#1504ad2523158caa40db4a2787cb01411994ea4f"
+
+fsevents@^1.0.0:
+  version "1.1.2"
+  resolved "https://registry.yarnpkg.com/fsevents/-/fsevents-1.1.2.tgz#3282b713fb3ad80ede0e9fcf4611b5aa6fc033f4"
+  dependencies:
+    nan "^2.3.0"
+    node-pre-gyp "^0.6.36"
+
+fstream-ignore@^1.0.5:
+  version "1.0.5"
+  resolved "https://registry.yarnpkg.com/fstream-ignore/-/fstream-ignore-1.0.5.tgz#9c31dae34767018fe1d249b24dada67d092da105"
+  dependencies:
+    fstream "^1.0.0"
+    inherits "2"
+    minimatch "^3.0.0"
+
+fstream@^1.0.0, fstream@^1.0.10, fstream@^1.0.2:
+  version "1.0.11"
+  resolved "https://registry.yarnpkg.com/fstream/-/fstream-1.0.11.tgz#5c1fb1f117477114f0632a0eb4b71b3cb0fd3171"
+  dependencies:
+    graceful-fs "^4.1.2"
+    inherits "~2.0.0"
+    mkdirp ">=0.5 0"
+    rimraf "2"
+
+function-bind@^1.0.2:
+  version "1.1.0"
+  resolved "https://registry.yarnpkg.com/function-bind/-/function-bind-1.1.0.tgz#16176714c801798e4e8f2cf7f7529467bb4a5771"
+
+functional-red-black-tree@^1.0.1:
+  version "1.0.1"
+  resolved "https://registry.yarnpkg.com/functional-red-black-tree/-/functional-red-black-tree-1.0.1.tgz#1b0ab3bd553b2a0d6399d29c0e3ea0b252078327"
+
+gauge@~2.7.3:
+  version "2.7.4"
+  resolved "https://registry.yarnpkg.com/gauge/-/gauge-2.7.4.tgz#2c03405c7538c39d7eb37b317022e325fb018bf7"
+  dependencies:
+    aproba "^1.0.3"
+    console-control-strings "^1.0.0"
+    has-unicode "^2.0.0"
+    object-assign "^4.1.0"
+    signal-exit "^3.0.0"
+    string-width "^1.0.1"
+    strip-ansi "^3.0.1"
+    wide-align "^1.1.0"
+
+get-caller-file@^1.0.1:
+  version "1.0.2"
+  resolved "https://registry.yarnpkg.com/get-caller-file/-/get-caller-file-1.0.2.tgz#f702e63127e7e231c160a80c1554acb70d5047e5"
+
+get-stream@^3.0.0:
+  version "3.0.0"
+  resolved "https://registry.yarnpkg.com/get-stream/-/get-stream-3.0.0.tgz#8e943d1358dc37555054ecbe2edb05aa174ede14"
+
+getpass@^0.1.1:
+  version "0.1.7"
+  resolved "https://registry.yarnpkg.com/getpass/-/getpass-0.1.7.tgz#5eff8e3e684d569ae4cb2b1282604e8ba62149fa"
+  dependencies:
+    assert-plus "^1.0.0"
+
+glob-base@^0.3.0:
+  version "0.3.0"
+  resolved "https://registry.yarnpkg.com/glob-base/-/glob-base-0.3.0.tgz#dbb164f6221b1c0b1ccf82aea328b497df0ea3c4"
+  dependencies:
+    glob-parent "^2.0.0"
+    is-glob "^2.0.0"
+
+glob-parent@^2.0.0:
+  version "2.0.0"
+  resolved "https://registry.yarnpkg.com/glob-parent/-/glob-parent-2.0.0.tgz#81383d72db054fcccf5336daa902f182f6edbb28"
+  dependencies:
+    is-glob "^2.0.0"
+
+glob@^7.0.3, glob@^7.0.5, glob@^7.1.2:
+  version "7.1.2"
+  resolved "https://registry.yarnpkg.com/glob/-/glob-7.1.2.tgz#c19c9df9a028702d678612384a6552404c636d15"
+  dependencies:
+    fs.realpath "^1.0.0"
+    inflight "^1.0.4"
+    inherits "2"
+    minimatch "^3.0.4"
+    once "^1.3.0"
+    path-is-absolute "^1.0.0"
+
+globals@^9.0.0, globals@^9.17.0:
+  version "9.18.0"
+  resolved "https://registry.yarnpkg.com/globals/-/globals-9.18.0.tgz#aa3896b3e69b487f17e31ed2143d69a8e30c2d8a"
+
+globby@^5.0.0:
+  version "5.0.0"
+  resolved "https://registry.yarnpkg.com/globby/-/globby-5.0.0.tgz#ebd84667ca0dbb330b99bcfc68eac2bc54370e0d"
+  dependencies:
+    array-union "^1.0.1"
+    arrify "^1.0.0"
+    glob "^7.0.3"
+    object-assign "^4.0.1"
+    pify "^2.0.0"
+    pinkie-promise "^2.0.0"
+
+graceful-fs@^4.1.2:
+  version "4.1.11"
+  resolved "https://registry.yarnpkg.com/graceful-fs/-/graceful-fs-4.1.11.tgz#0e8bdfe4d1ddb8854d64e04ea7c00e2a026e5658"
+
+har-schema@^1.0.5:
+  version "1.0.5"
+  resolved "https://registry.yarnpkg.com/har-schema/-/har-schema-1.0.5.tgz#d263135f43307c02c602afc8fe95970c0151369e"
+
+har-validator@~4.2.1:
+  version "4.2.1"
+  resolved "https://registry.yarnpkg.com/har-validator/-/har-validator-4.2.1.tgz#33481d0f1bbff600dd203d75812a6a5fba002e2a"
+  dependencies:
+    ajv "^4.9.1"
+    har-schema "^1.0.5"
+
+has-ansi@^2.0.0:
+  version "2.0.0"
+  resolved "https://registry.yarnpkg.com/has-ansi/-/has-ansi-2.0.0.tgz#34f5049ce1ecdf2b0649af3ef24e45ed35416d91"
+  dependencies:
+    ansi-regex "^2.0.0"
+
+has-flag@^2.0.0:
+  version "2.0.0"
+  resolved "https://registry.yarnpkg.com/has-flag/-/has-flag-2.0.0.tgz#e8207af1cc7b30d446cc70b734b5e8be18f88d51"
+
+has-unicode@^2.0.0:
+  version "2.0.1"
+  resolved "https://registry.yarnpkg.com/has-unicode/-/has-unicode-2.0.1.tgz#e0e6fe6a28cf51138855e086d1691e771de2a8b9"
+
+has@^1.0.1:
+  version "1.0.1"
+  resolved "https://registry.yarnpkg.com/has/-/has-1.0.1.tgz#8461733f538b0837c9361e39a9ab9e9704dc2f28"
+  dependencies:
+    function-bind "^1.0.2"
+
+hash-base@^2.0.0:
+  version "2.0.2"
+  resolved "https://registry.yarnpkg.com/hash-base/-/hash-base-2.0.2.tgz#66ea1d856db4e8a5470cadf6fce23ae5244ef2e1"
+  dependencies:
+    inherits "^2.0.1"
+
+hash.js@^1.0.0, hash.js@^1.0.3:
+  version "1.1.3"
+  resolved "https://registry.yarnpkg.com/hash.js/-/hash.js-1.1.3.tgz#340dedbe6290187151c1ea1d777a3448935df846"
+  dependencies:
+    inherits "^2.0.3"
+    minimalistic-assert "^1.0.0"
+
+hawk@~3.1.3:
+  version "3.1.3"
+  resolved "https://registry.yarnpkg.com/hawk/-/hawk-3.1.3.tgz#078444bd7c1640b0fe540d2c9b73d59678e8e1c4"
+  dependencies:
+    boom "2.x.x"
+    cryptiles "2.x.x"
+    hoek "2.x.x"
+    sntp "1.x.x"
+
+hmac-drbg@^1.0.0:
+  version "1.0.1"
+  resolved "https://registry.yarnpkg.com/hmac-drbg/-/hmac-drbg-1.0.1.tgz#d2745701025a6c775a6c545793ed502fc0c649a1"
+  dependencies:
+    hash.js "^1.0.3"
+    minimalistic-assert "^1.0.0"
+    minimalistic-crypto-utils "^1.0.1"
+
+hoek@2.x.x:
+  version "2.16.3"
+  resolved "https://registry.yarnpkg.com/hoek/-/hoek-2.16.3.tgz#20bb7403d3cea398e91dc4710a8ff1b8274a25ed"
+
+home-or-tmp@^2.0.0:
+  version "2.0.0"
+  resolved "https://registry.yarnpkg.com/home-or-tmp/-/home-or-tmp-2.0.0.tgz#e36c3f2d2cae7d746a857e38d18d5f32a7882db8"
+  dependencies:
+    os-homedir "^1.0.0"
+    os-tmpdir "^1.0.1"
+
+hosted-git-info@^2.1.4:
+  version "2.5.0"
+  resolved "https://registry.yarnpkg.com/hosted-git-info/-/hosted-git-info-2.5.0.tgz#6d60e34b3abbc8313062c3b798ef8d901a07af3c"
+
+http-signature@~1.1.0:
+  version "1.1.1"
+  resolved "https://registry.yarnpkg.com/http-signature/-/http-signature-1.1.1.tgz#df72e267066cd0ac67fb76adf8e134a8fbcf91bf"
+  dependencies:
+    assert-plus "^0.2.0"
+    jsprim "^1.2.2"
+    sshpk "^1.7.0"
+
+https-browserify@0.0.1:
+  version "0.0.1"
+  resolved "https://registry.yarnpkg.com/https-browserify/-/https-browserify-0.0.1.tgz#3f91365cabe60b77ed0ebba24b454e3e09d95a82"
+
+iconv-lite@^0.4.17:
+  version "0.4.18"
+  resolved "https://registry.yarnpkg.com/iconv-lite/-/iconv-lite-0.4.18.tgz#23d8656b16aae6742ac29732ea8f0336a4789cf2"
+
+ieee754@^1.1.4:
+  version "1.1.8"
+  resolved "https://registry.yarnpkg.com/ieee754/-/ieee754-1.1.8.tgz#be33d40ac10ef1926701f6f08a2d86fbfd1ad3e4"
+
+ignore@^3.3.3:
+  version "3.3.3"
+  resolved "https://registry.yarnpkg.com/ignore/-/ignore-3.3.3.tgz#432352e57accd87ab3110e82d3fea0e47812156d"
+
+imurmurhash@^0.1.4:
+  version "0.1.4"
+  resolved "https://registry.yarnpkg.com/imurmurhash/-/imurmurhash-0.1.4.tgz#9218b9b2b928a238b13dc4fb6b6d576f231453ea"
+
+indexof@0.0.1:
+  version "0.0.1"
+  resolved "https://registry.yarnpkg.com/indexof/-/indexof-0.0.1.tgz#82dc336d232b9062179d05ab3293a66059fd435d"
+
+inflight@^1.0.4:
+  version "1.0.6"
+  resolved "https://registry.yarnpkg.com/inflight/-/inflight-1.0.6.tgz#49bd6331d7d02d0c09bc910a1075ba8165b56df9"
+  dependencies:
+    once "^1.3.0"
+    wrappy "1"
+
+inherits@2, inherits@^2.0.1, inherits@^2.0.3, inherits@~2.0.0, inherits@~2.0.1, inherits@~2.0.3:
+  version "2.0.3"
+  resolved "https://registry.yarnpkg.com/inherits/-/inherits-2.0.3.tgz#633c2c83e3da42a502f52466022480f4208261de"
+
+inherits@2.0.1:
+  version "2.0.1"
+  resolved "https://registry.yarnpkg.com/inherits/-/inherits-2.0.1.tgz#b17d08d326b4423e568eff719f91b0b1cbdf69f1"
+
+ini@~1.3.0:
+  version "1.3.4"
+  resolved "https://registry.yarnpkg.com/ini/-/ini-1.3.4.tgz#0537cb79daf59b59a1a517dff706c86ec039162e"
+
+inquirer@^3.0.6:
+  version "3.2.1"
+  resolved "https://registry.yarnpkg.com/inquirer/-/inquirer-3.2.1.tgz#06ceb0f540f45ca548c17d6840959878265fa175"
+  dependencies:
+    ansi-escapes "^2.0.0"
+    chalk "^2.0.0"
+    cli-cursor "^2.1.0"
+    cli-width "^2.0.0"
+    external-editor "^2.0.4"
+    figures "^2.0.0"
+    lodash "^4.3.0"
+    mute-stream "0.0.7"
+    run-async "^2.2.0"
+    rx-lite "^4.0.8"
+    rx-lite-aggregates "^4.0.8"
+    string-width "^2.1.0"
+    strip-ansi "^4.0.0"
+    through "^2.3.6"
+
+interpret@^1.0.0:
+  version "1.0.3"
+  resolved "https://registry.yarnpkg.com/interpret/-/interpret-1.0.3.tgz#cbc35c62eeee73f19ab7b10a801511401afc0f90"
+
+invariant@^2.2.0, invariant@^2.2.2:
+  version "2.2.2"
+  resolved "https://registry.yarnpkg.com/invariant/-/invariant-2.2.2.tgz#9e1f56ac0acdb6bf303306f338be3b204ae60360"
+  dependencies:
+    loose-envify "^1.0.0"
+
+invert-kv@^1.0.0:
+  version "1.0.0"
+  resolved "https://registry.yarnpkg.com/invert-kv/-/invert-kv-1.0.0.tgz#104a8e4aaca6d3d8cd157a8ef8bfab2d7a3ffdb6"
+
+is-arrayish@^0.2.1:
+  version "0.2.1"
+  resolved "https://registry.yarnpkg.com/is-arrayish/-/is-arrayish-0.2.1.tgz#77c99840527aa8ecb1a8ba697b80645a7a926a9d"
+
+is-binary-path@^1.0.0:
+  version "1.0.1"
+  resolved "https://registry.yarnpkg.com/is-binary-path/-/is-binary-path-1.0.1.tgz#75f16642b480f187a711c814161fd3a4a7655898"
+  dependencies:
+    binary-extensions "^1.0.0"
+
+is-buffer@^1.1.5:
+  version "1.1.5"
+  resolved "https://registry.yarnpkg.com/is-buffer/-/is-buffer-1.1.5.tgz#1f3b26ef613b214b88cbca23cc6c01d87961eecc"
+
+is-builtin-module@^1.0.0:
+  version "1.0.0"
+  resolved "https://registry.yarnpkg.com/is-builtin-module/-/is-builtin-module-1.0.0.tgz#540572d34f7ac3119f8f76c30cbc1b1e037affbe"
+  dependencies:
+    builtin-modules "^1.0.0"
+
+is-dotfile@^1.0.0:
+  version "1.0.3"
+  resolved "https://registry.yarnpkg.com/is-dotfile/-/is-dotfile-1.0.3.tgz#a6a2f32ffd2dfb04f5ca25ecd0f6b83cf798a1e1"
+
+is-equal-shallow@^0.1.3:
+  version "0.1.3"
+  resolved "https://registry.yarnpkg.com/is-equal-shallow/-/is-equal-shallow-0.1.3.tgz#2238098fc221de0bcfa5d9eac4c45d638aa1c534"
+  dependencies:
+    is-primitive "^2.0.0"
+
+is-extendable@^0.1.1:
+  version "0.1.1"
+  resolved "https://registry.yarnpkg.com/is-extendable/-/is-extendable-0.1.1.tgz#62b110e289a471418e3ec36a617d472e301dfc89"
+
+is-extglob@^1.0.0:
+  version "1.0.0"
+  resolved "https://registry.yarnpkg.com/is-extglob/-/is-extglob-1.0.0.tgz#ac468177c4943405a092fc8f29760c6ffc6206c0"
+
+is-finite@^1.0.0:
+  version "1.0.2"
+  resolved "https://registry.yarnpkg.com/is-finite/-/is-finite-1.0.2.tgz#cc6677695602be550ef11e8b4aa6305342b6d0aa"
+  dependencies:
+    number-is-nan "^1.0.0"
+
+is-fullwidth-code-point@^1.0.0:
+  version "1.0.0"
+  resolved "https://registry.yarnpkg.com/is-fullwidth-code-point/-/is-fullwidth-code-point-1.0.0.tgz#ef9e31386f031a7f0d643af82fde50c457ef00cb"
+  dependencies:
+    number-is-nan "^1.0.0"
+
+is-fullwidth-code-point@^2.0.0:
+  version "2.0.0"
+  resolved "https://registry.yarnpkg.com/is-fullwidth-code-point/-/is-fullwidth-code-point-2.0.0.tgz#a3b30a5c4f199183167aaab93beefae3ddfb654f"
+
+is-glob@^2.0.0, is-glob@^2.0.1:
+  version "2.0.1"
+  resolved "https://registry.yarnpkg.com/is-glob/-/is-glob-2.0.1.tgz#d096f926a3ded5600f3fdfd91198cb0888c2d863"
+  dependencies:
+    is-extglob "^1.0.0"
+
+is-number@^2.1.0:
+  version "2.1.0"
+  resolved "https://registry.yarnpkg.com/is-number/-/is-number-2.1.0.tgz#01fcbbb393463a548f2f466cce16dece49db908f"
+  dependencies:
+    kind-of "^3.0.2"
+
+is-number@^3.0.0:
+  version "3.0.0"
+  resolved "https://registry.yarnpkg.com/is-number/-/is-number-3.0.0.tgz#24fd6201a4782cf50561c810276afc7d12d71195"
+  dependencies:
+    kind-of "^3.0.2"
+
+is-path-cwd@^1.0.0:
+  version "1.0.0"
+  resolved "https://registry.yarnpkg.com/is-path-cwd/-/is-path-cwd-1.0.0.tgz#d225ec23132e89edd38fda767472e62e65f1106d"
+
+is-path-in-cwd@^1.0.0:
+  version "1.0.0"
+  resolved "https://registry.yarnpkg.com/is-path-in-cwd/-/is-path-in-cwd-1.0.0.tgz#6477582b8214d602346094567003be8a9eac04dc"
+  dependencies:
+    is-path-inside "^1.0.0"
+
+is-path-inside@^1.0.0:
+  version "1.0.0"
+  resolved "https://registry.yarnpkg.com/is-path-inside/-/is-path-inside-1.0.0.tgz#fc06e5a1683fbda13de667aff717bbc10a48f37f"
+  dependencies:
+    path-is-inside "^1.0.1"
+
+is-posix-bracket@^0.1.0:
+  version "0.1.1"
+  resolved "https://registry.yarnpkg.com/is-posix-bracket/-/is-posix-bracket-0.1.1.tgz#3334dc79774368e92f016e6fbc0a88f5cd6e6bc4"
+
+is-primitive@^2.0.0:
+  version "2.0.0"
+  resolved "https://registry.yarnpkg.com/is-primitive/-/is-primitive-2.0.0.tgz#207bab91638499c07b2adf240a41a87210034575"
+
+is-promise@^2.1.0:
+  version "2.1.0"
+  resolved "https://registry.yarnpkg.com/is-promise/-/is-promise-2.1.0.tgz#79a2a9ece7f096e80f36d2b2f3bc16c1ff4bf3fa"
+
+is-resolvable@^1.0.0:
+  version "1.0.0"
+  resolved "https://registry.yarnpkg.com/is-resolvable/-/is-resolvable-1.0.0.tgz#8df57c61ea2e3c501408d100fb013cf8d6e0cc62"
+  dependencies:
+    tryit "^1.0.1"
+
+is-stream@^1.1.0:
+  version "1.1.0"
+  resolved "https://registry.yarnpkg.com/is-stream/-/is-stream-1.1.0.tgz#12d4a3dd4e68e0b79ceb8dbc84173ae80d91ca44"
+
+is-typedarray@~1.0.0:
+  version "1.0.0"
+  resolved "https://registry.yarnpkg.com/is-typedarray/-/is-typedarray-1.0.0.tgz#e479c80858df0c1b11ddda6940f96011fcda4a9a"
+
+isarray@1.0.0, isarray@^1.0.0, isarray@~1.0.0:
+  version "1.0.0"
+  resolved "https://registry.yarnpkg.com/isarray/-/isarray-1.0.0.tgz#bb935d48582cba168c06834957a54a3e07124f11"
+
+isexe@^2.0.0:
+  version "2.0.0"
+  resolved "https://registry.yarnpkg.com/isexe/-/isexe-2.0.0.tgz#e8fbf374dc556ff8947a10dcb0572d633f2cfa10"
+
+isobject@^2.0.0:
+  version "2.1.0"
+  resolved "https://registry.yarnpkg.com/isobject/-/isobject-2.1.0.tgz#f065561096a3f1da2ef46272f815c840d87e0c89"
+  dependencies:
+    isarray "1.0.0"
+
+isstream@~0.1.2:
+  version "0.1.2"
+  resolved "https://registry.yarnpkg.com/isstream/-/isstream-0.1.2.tgz#47e63f7af55afa6f92e1500e690eb8b8529c099a"
+
+js-tokens@^3.0.0:
+  version "3.0.2"
+  resolved "https://registry.yarnpkg.com/js-tokens/-/js-tokens-3.0.2.tgz#9866df395102130e38f7f996bceb65443209c25b"
+
+js-yaml@^3.8.4:
+  version "3.9.0"
+  resolved "https://registry.yarnpkg.com/js-yaml/-/js-yaml-3.9.0.tgz#4ffbbf25c2ac963b8299dc74da7e3740de1c18ce"
+  dependencies:
+    argparse "^1.0.7"
+    esprima "^4.0.0"
+
+jsbn@~0.1.0:
+  version "0.1.1"
+  resolved "https://registry.yarnpkg.com/jsbn/-/jsbn-0.1.1.tgz#a5e654c2e5a2deb5f201d96cefbca80c0ef2f513"
+
+jschardet@^1.4.2:
+  version "1.5.0"
+  resolved "https://registry.yarnpkg.com/jschardet/-/jschardet-1.5.0.tgz#a61f310306a5a71188e1b1acd08add3cfbb08b1e"
+
+jsesc@^1.3.0:
+  version "1.3.0"
+  resolved "https://registry.yarnpkg.com/jsesc/-/jsesc-1.3.0.tgz#46c3fec8c1892b12b0833db9bc7622176dbab34b"
+
+jsesc@~0.5.0:
+  version "0.5.0"
+  resolved "https://registry.yarnpkg.com/jsesc/-/jsesc-0.5.0.tgz#e7dee66e35d6fc16f710fe91d5cf69f70f08911d"
+
+json-loader@^0.5.4:
+  version "0.5.7"
+  resolved "https://registry.yarnpkg.com/json-loader/-/json-loader-0.5.7.tgz#dca14a70235ff82f0ac9a3abeb60d337a365185d"
+
+json-schema-traverse@^0.3.0:
+  version "0.3.1"
+  resolved "https://registry.yarnpkg.com/json-schema-traverse/-/json-schema-traverse-0.3.1.tgz#349a6d44c53a51de89b40805c5d5e59b417d3340"
+
+json-schema@0.2.3:
+  version "0.2.3"
+  resolved "https://registry.yarnpkg.com/json-schema/-/json-schema-0.2.3.tgz#b480c892e59a2f05954ce727bd3f2a4e882f9e13"
+
+json-stable-stringify@^1.0.1:
+  version "1.0.1"
+  resolved "https://registry.yarnpkg.com/json-stable-stringify/-/json-stable-stringify-1.0.1.tgz#9a759d39c5f2ff503fd5300646ed445f88c4f9af"
+  dependencies:
+    jsonify "~0.0.0"
+
+json-stringify-safe@~5.0.1:
+  version "5.0.1"
+  resolved "https://registry.yarnpkg.com/json-stringify-safe/-/json-stringify-safe-5.0.1.tgz#1296a2d58fd45f19a0f6ce01d65701e2c735b6eb"
+
+json5@^0.5.0, json5@^0.5.1:
+  version "0.5.1"
+  resolved "https://registry.yarnpkg.com/json5/-/json5-0.5.1.tgz#1eade7acc012034ad84e2396767ead9fa5495821"
+
+jsonify@~0.0.0:
+  version "0.0.0"
+  resolved "https://registry.yarnpkg.com/jsonify/-/jsonify-0.0.0.tgz#2c74b6ee41d93ca51b7b5aaee8f503631d252a73"
+
+jsprim@^1.2.2:
+  version "1.4.0"
+  resolved "https://registry.yarnpkg.com/jsprim/-/jsprim-1.4.0.tgz#a3b87e40298d8c380552d8cc7628a0bb95a22918"
+  dependencies:
+    assert-plus "1.0.0"
+    extsprintf "1.0.2"
+    json-schema "0.2.3"
+    verror "1.3.6"
+
+kind-of@^3.0.2:
+  version "3.2.2"
+  resolved "https://registry.yarnpkg.com/kind-of/-/kind-of-3.2.2.tgz#31ea21a734bab9bbb0f32466d893aea51e4a3c64"
+  dependencies:
+    is-buffer "^1.1.5"
+
+kind-of@^4.0.0:
+  version "4.0.0"
+  resolved "https://registry.yarnpkg.com/kind-of/-/kind-of-4.0.0.tgz#20813df3d712928b207378691a45066fae72dd57"
+  dependencies:
+    is-buffer "^1.1.5"
+
+lazy-cache@^1.0.3:
+  version "1.0.4"
+  resolved "https://registry.yarnpkg.com/lazy-cache/-/lazy-cache-1.0.4.tgz#a1d78fc3a50474cb80845d3b3b6e1da49a446e8e"
+
+lcid@^1.0.0:
+  version "1.0.0"
+  resolved "https://registry.yarnpkg.com/lcid/-/lcid-1.0.0.tgz#308accafa0bc483a3867b4b6f2b9506251d1b835"
+  dependencies:
+    invert-kv "^1.0.0"
+
+levn@^0.3.0, levn@~0.3.0:
+  version "0.3.0"
+  resolved "https://registry.yarnpkg.com/levn/-/levn-0.3.0.tgz#3b09924edf9f083c0490fdd4c0bc4421e04764ee"
+  dependencies:
+    prelude-ls "~1.1.2"
+    type-check "~0.3.2"
+
+load-json-file@^2.0.0:
+  version "2.0.0"
+  resolved "https://registry.yarnpkg.com/load-json-file/-/load-json-file-2.0.0.tgz#7947e42149af80d696cbf797bcaabcfe1fe29ca8"
+  dependencies:
+    graceful-fs "^4.1.2"
+    parse-json "^2.2.0"
+    pify "^2.0.0"
+    strip-bom "^3.0.0"
+
+loader-runner@^2.3.0:
+  version "2.3.0"
+  resolved "https://registry.yarnpkg.com/loader-runner/-/loader-runner-2.3.0.tgz#f482aea82d543e07921700d5a46ef26fdac6b8a2"
+
+loader-utils@^1.0.2, loader-utils@^1.1.0:
+  version "1.1.0"
+  resolved "https://registry.yarnpkg.com/loader-utils/-/loader-utils-1.1.0.tgz#c98aef488bcceda2ffb5e2de646d6a754429f5cd"
+  dependencies:
+    big.js "^3.1.3"
+    emojis-list "^2.0.0"
+    json5 "^0.5.0"
+
+locate-path@^2.0.0:
+  version "2.0.0"
+  resolved "https://registry.yarnpkg.com/locate-path/-/locate-path-2.0.0.tgz#2b568b265eec944c6d9c0de9c3dbbbca0354cd8e"
+  dependencies:
+    p-locate "^2.0.0"
+    path-exists "^3.0.0"
+
+lodash.cond@^4.3.0:
+  version "4.5.2"
+  resolved "https://registry.yarnpkg.com/lodash.cond/-/lodash.cond-4.5.2.tgz#f471a1da486be60f6ab955d17115523dd1d255d5"
+
+lodash@^4.0.0, lodash@^4.14.0, lodash@^4.17.4, lodash@^4.2.0, lodash@^4.3.0:
+  version "4.17.4"
+  resolved "https://registry.yarnpkg.com/lodash/-/lodash-4.17.4.tgz#78203a4d1c328ae1d86dca6460e369b57f4055ae"
+
+longest@^1.0.1:
+  version "1.0.1"
+  resolved "https://registry.yarnpkg.com/longest/-/longest-1.0.1.tgz#30a0b2da38f73770e8294a0d22e6625ed77d0097"
+
+loose-envify@^1.0.0:
+  version "1.3.1"
+  resolved "https://registry.yarnpkg.com/loose-envify/-/loose-envify-1.3.1.tgz#d1a8ad33fa9ce0e713d65fdd0ac8b748d478c848"
+  dependencies:
+    js-tokens "^3.0.0"
+
+lru-cache@^4.0.1:
+  version "4.1.1"
+  resolved "https://registry.yarnpkg.com/lru-cache/-/lru-cache-4.1.1.tgz#622e32e82488b49279114a4f9ecf45e7cd6bba55"
+  dependencies:
+    pseudomap "^1.0.2"
+    yallist "^2.1.2"
+
+make-dir@^1.0.0:
+  version "1.0.0"
+  resolved "https://registry.yarnpkg.com/make-dir/-/make-dir-1.0.0.tgz#97a011751e91dd87cfadef58832ebb04936de978"
+  dependencies:
+    pify "^2.3.0"
+
+mem@^1.1.0:
+  version "1.1.0"
+  resolved "https://registry.yarnpkg.com/mem/-/mem-1.1.0.tgz#5edd52b485ca1d900fe64895505399a0dfa45f76"
+  dependencies:
+    mimic-fn "^1.0.0"
+
+memory-fs@^0.4.0, memory-fs@~0.4.1:
+  version "0.4.1"
+  resolved "https://registry.yarnpkg.com/memory-fs/-/memory-fs-0.4.1.tgz#3a9a20b8462523e447cfbc7e8bb80ed667bfc552"
+  dependencies:
+    errno "^0.1.3"
+    readable-stream "^2.0.1"
+
+micromatch@^2.1.5:
+  version "2.3.11"
+  resolved "https://registry.yarnpkg.com/micromatch/-/micromatch-2.3.11.tgz#86677c97d1720b363431d04d0d15293bd38c1565"
+  dependencies:
+    arr-diff "^2.0.0"
+    array-unique "^0.2.1"
+    braces "^1.8.2"
+    expand-brackets "^0.1.4"
+    extglob "^0.3.1"
+    filename-regex "^2.0.0"
+    is-extglob "^1.0.0"
+    is-glob "^2.0.1"
+    kind-of "^3.0.2"
+    normalize-path "^2.0.1"
+    object.omit "^2.0.0"
+    parse-glob "^3.0.4"
+    regex-cache "^0.4.2"
+
+miller-rabin@^4.0.0:
+  version "4.0.0"
+  resolved "https://registry.yarnpkg.com/miller-rabin/-/miller-rabin-4.0.0.tgz#4a62fb1d42933c05583982f4c716f6fb9e6c6d3d"
+  dependencies:
+    bn.js "^4.0.0"
+    brorand "^1.0.1"
+
+mime-db@~1.29.0:
+  version "1.29.0"
+  resolved "https://registry.yarnpkg.com/mime-db/-/mime-db-1.29.0.tgz#48d26d235589651704ac5916ca06001914266878"
+
+mime-types@^2.1.12, mime-types@~2.1.7:
+  version "2.1.16"
+  resolved "https://registry.yarnpkg.com/mime-types/-/mime-types-2.1.16.tgz#2b858a52e5ecd516db897ac2be87487830698e23"
+  dependencies:
+    mime-db "~1.29.0"
+
+mimic-fn@^1.0.0:
+  version "1.1.0"
+  resolved "https://registry.yarnpkg.com/mimic-fn/-/mimic-fn-1.1.0.tgz#e667783d92e89dbd342818b5230b9d62a672ad18"
+
+minimalistic-assert@^1.0.0:
+  version "1.0.0"
+  resolved "https://registry.yarnpkg.com/minimalistic-assert/-/minimalistic-assert-1.0.0.tgz#702be2dda6b37f4836bcb3f5db56641b64a1d3d3"
+
+minimalistic-crypto-utils@^1.0.0, minimalistic-crypto-utils@^1.0.1:
+  version "1.0.1"
+  resolved "https://registry.yarnpkg.com/minimalistic-crypto-utils/-/minimalistic-crypto-utils-1.0.1.tgz#f6c00c1c0b082246e5c4d99dfb8c7c083b2b582a"
+
+minimatch@^3.0.0, minimatch@^3.0.2, minimatch@^3.0.3, minimatch@^3.0.4:
+  version "3.0.4"
+  resolved "https://registry.yarnpkg.com/minimatch/-/minimatch-3.0.4.tgz#5166e286457f03306064be5497e8dbb0c3d32083"
+  dependencies:
+    brace-expansion "^1.1.7"
+
+minimist@0.0.8:
+  version "0.0.8"
+  resolved "https://registry.yarnpkg.com/minimist/-/minimist-0.0.8.tgz#857fcabfc3397d2625b8228262e86aa7a011b05d"
+
+minimist@^1.2.0:
+  version "1.2.0"
+  resolved "https://registry.yarnpkg.com/minimist/-/minimist-1.2.0.tgz#a35008b20f41383eec1fb914f4cd5df79a264284"
+
+"mkdirp@>=0.5 0", mkdirp@^0.5.1, mkdirp@~0.5.0:
+  version "0.5.1"
+  resolved "https://registry.yarnpkg.com/mkdirp/-/mkdirp-0.5.1.tgz#30057438eac6cf7f8c4767f38648d6697d75c903"
+  dependencies:
+    minimist "0.0.8"
+
+ms@2.0.0:
+  version "2.0.0"
+  resolved "https://registry.yarnpkg.com/ms/-/ms-2.0.0.tgz#5608aeadfc00be6c2901df5f9861788de0d597c8"
+
+mute-stream@0.0.7:
+  version "0.0.7"
+  resolved "https://registry.yarnpkg.com/mute-stream/-/mute-stream-0.0.7.tgz#3075ce93bc21b8fab43e1bc4da7e8115ed1e7bab"
+
+nan@^2.3.0:
+  version "2.6.2"
+  resolved "https://registry.yarnpkg.com/nan/-/nan-2.6.2.tgz#e4ff34e6c95fdfb5aecc08de6596f43605a7db45"
+
+natural-compare@^1.4.0:
+  version "1.4.0"
+  resolved "https://registry.yarnpkg.com/natural-compare/-/natural-compare-1.4.0.tgz#4abebfeed7541f2c27acfb29bdbbd15c8d5ba4f7"
+
+node-libs-browser@^2.0.0:
+  version "2.0.0"
+  resolved "https://registry.yarnpkg.com/node-libs-browser/-/node-libs-browser-2.0.0.tgz#a3a59ec97024985b46e958379646f96c4b616646"
+  dependencies:
+    assert "^1.1.1"
+    browserify-zlib "^0.1.4"
+    buffer "^4.3.0"
+    console-browserify "^1.1.0"
+    constants-browserify "^1.0.0"
+    crypto-browserify "^3.11.0"
+    domain-browser "^1.1.1"
+    events "^1.0.0"
+    https-browserify "0.0.1"
+    os-browserify "^0.2.0"
+    path-browserify "0.0.0"
+    process "^0.11.0"
+    punycode "^1.2.4"
+    querystring-es3 "^0.2.0"
+    readable-stream "^2.0.5"
+    stream-browserify "^2.0.1"
+    stream-http "^2.3.1"
+    string_decoder "^0.10.25"
+    timers-browserify "^2.0.2"
+    tty-browserify "0.0.0"
+    url "^0.11.0"
+    util "^0.10.3"
+    vm-browserify "0.0.4"
+
+node-pre-gyp@^0.6.36:
+  version "0.6.36"
+  resolved "https://registry.yarnpkg.com/node-pre-gyp/-/node-pre-gyp-0.6.36.tgz#db604112cb74e0d477554e9b505b17abddfab786"
+  dependencies:
+    mkdirp "^0.5.1"
+    nopt "^4.0.1"
+    npmlog "^4.0.2"
+    rc "^1.1.7"
+    request "^2.81.0"
+    rimraf "^2.6.1"
+    semver "^5.3.0"
+    tar "^2.2.1"
+    tar-pack "^3.4.0"
+
+nopt@^4.0.1:
+  version "4.0.1"
+  resolved "https://registry.yarnpkg.com/nopt/-/nopt-4.0.1.tgz#d0d4685afd5415193c8c7505602d0d17cd64474d"
+  dependencies:
+    abbrev "1"
+    osenv "^0.1.4"
+
+normalize-package-data@^2.3.2:
+  version "2.4.0"
+  resolved "https://registry.yarnpkg.com/normalize-package-data/-/normalize-package-data-2.4.0.tgz#12f95a307d58352075a04907b84ac8be98ac012f"
+  dependencies:
+    hosted-git-info "^2.1.4"
+    is-builtin-module "^1.0.0"
+    semver "2 || 3 || 4 || 5"
+    validate-npm-package-license "^3.0.1"
+
+normalize-path@^2.0.1:
+  version "2.1.1"
+  resolved "https://registry.yarnpkg.com/normalize-path/-/normalize-path-2.1.1.tgz#1ab28b556e198363a8c1a6f7e6fa20137fe6aed9"
+  dependencies:
+    remove-trailing-separator "^1.0.1"
+
+npm-run-path@^2.0.0:
+  version "2.0.2"
+  resolved "https://registry.yarnpkg.com/npm-run-path/-/npm-run-path-2.0.2.tgz#35a9232dfa35d7067b4cb2ddf2357b1871536c5f"
+  dependencies:
+    path-key "^2.0.0"
+
+npmlog@^4.0.2:
+  version "4.1.2"
+  resolved "https://registry.yarnpkg.com/npmlog/-/npmlog-4.1.2.tgz#08a7f2a8bf734604779a9efa4ad5cc717abb954b"
+  dependencies:
+    are-we-there-yet "~1.1.2"
+    console-control-strings "~1.1.0"
+    gauge "~2.7.3"
+    set-blocking "~2.0.0"
+
+number-is-nan@^1.0.0:
+  version "1.0.1"
+  resolved "https://registry.yarnpkg.com/number-is-nan/-/number-is-nan-1.0.1.tgz#097b602b53422a522c1afb8790318336941a011d"
+
+oauth-sign@~0.8.1:
+  version "0.8.2"
+  resolved "https://registry.yarnpkg.com/oauth-sign/-/oauth-sign-0.8.2.tgz#46a6ab7f0aead8deae9ec0565780b7d4efeb9d43"
+
+object-assign@^4.0.1, object-assign@^4.1.0:
+  version "4.1.1"
+  resolved "https://registry.yarnpkg.com/object-assign/-/object-assign-4.1.1.tgz#2109adc7965887cfc05cbbd442cac8bfbb360863"
+
+object.omit@^2.0.0:
+  version "2.0.1"
+  resolved "https://registry.yarnpkg.com/object.omit/-/object.omit-2.0.1.tgz#1a9c744829f39dbb858c76ca3579ae2a54ebd1fa"
+  dependencies:
+    for-own "^0.1.4"
+    is-extendable "^0.1.1"
+
+once@^1.3.0, once@^1.3.3:
+  version "1.4.0"
+  resolved "https://registry.yarnpkg.com/once/-/once-1.4.0.tgz#583b1aa775961d4b113ac17d9c50baef9dd76bd1"
+  dependencies:
+    wrappy "1"
+
+onetime@^2.0.0:
+  version "2.0.1"
+  resolved "https://registry.yarnpkg.com/onetime/-/onetime-2.0.1.tgz#067428230fd67443b2794b22bba528b6867962d4"
+  dependencies:
+    mimic-fn "^1.0.0"
+
+optionator@^0.8.2:
+  version "0.8.2"
+  resolved "https://registry.yarnpkg.com/optionator/-/optionator-0.8.2.tgz#364c5e409d3f4d6301d6c0b4c05bba50180aeb64"
+  dependencies:
+    deep-is "~0.1.3"
+    fast-levenshtein "~2.0.4"
+    levn "~0.3.0"
+    prelude-ls "~1.1.2"
+    type-check "~0.3.2"
+    wordwrap "~1.0.0"
+
+os-browserify@^0.2.0:
+  version "0.2.1"
+  resolved "https://registry.yarnpkg.com/os-browserify/-/os-browserify-0.2.1.tgz#63fc4ccee5d2d7763d26bbf8601078e6c2e0044f"
+
+os-homedir@^1.0.0:
+  version "1.0.2"
+  resolved "https://registry.yarnpkg.com/os-homedir/-/os-homedir-1.0.2.tgz#ffbc4988336e0e833de0c168c7ef152121aa7fb3"
+
+os-locale@^2.0.0:
+  version "2.1.0"
+  resolved "https://registry.yarnpkg.com/os-locale/-/os-locale-2.1.0.tgz#42bc2900a6b5b8bd17376c8e882b65afccf24bf2"
+  dependencies:
+    execa "^0.7.0"
+    lcid "^1.0.0"
+    mem "^1.1.0"
+
+os-tmpdir@^1.0.0, os-tmpdir@^1.0.1, os-tmpdir@~1.0.1:
+  version "1.0.2"
+  resolved "https://registry.yarnpkg.com/os-tmpdir/-/os-tmpdir-1.0.2.tgz#bbe67406c79aa85c5cfec766fe5734555dfa1274"
+
+osenv@^0.1.4:
+  version "0.1.4"
+  resolved "https://registry.yarnpkg.com/osenv/-/osenv-0.1.4.tgz#42fe6d5953df06c8064be6f176c3d05aaaa34644"
+  dependencies:
+    os-homedir "^1.0.0"
+    os-tmpdir "^1.0.0"
+
+p-finally@^1.0.0:
+  version "1.0.0"
+  resolved "https://registry.yarnpkg.com/p-finally/-/p-finally-1.0.0.tgz#3fbcfb15b899a44123b34b6dcc18b724336a2cae"
+
+p-limit@^1.1.0:
+  version "1.1.0"
+  resolved "https://registry.yarnpkg.com/p-limit/-/p-limit-1.1.0.tgz#b07ff2d9a5d88bec806035895a2bab66a27988bc"
+
+p-locate@^2.0.0:
+  version "2.0.0"
+  resolved "https://registry.yarnpkg.com/p-locate/-/p-locate-2.0.0.tgz#20a0103b222a70c8fd39cc2e580680f3dde5ec43"
+  dependencies:
+    p-limit "^1.1.0"
+
+pako@~0.2.0:
+  version "0.2.9"
+  resolved "https://registry.yarnpkg.com/pako/-/pako-0.2.9.tgz#f3f7522f4ef782348da8161bad9ecfd51bf83a75"
+
+parse-asn1@^5.0.0:
+  version "5.1.0"
+  resolved "https://registry.yarnpkg.com/parse-asn1/-/parse-asn1-5.1.0.tgz#37c4f9b7ed3ab65c74817b5f2480937fbf97c712"
+  dependencies:
+    asn1.js "^4.0.0"
+    browserify-aes "^1.0.0"
+    create-hash "^1.1.0"
+    evp_bytestokey "^1.0.0"
+    pbkdf2 "^3.0.3"
+
+parse-glob@^3.0.4:
+  version "3.0.4"
+  resolved "https://registry.yarnpkg.com/parse-glob/-/parse-glob-3.0.4.tgz#b2c376cfb11f35513badd173ef0bb6e3a388391c"
+  dependencies:
+    glob-base "^0.3.0"
+    is-dotfile "^1.0.0"
+    is-extglob "^1.0.0"
+    is-glob "^2.0.0"
+
+parse-json@^2.2.0:
+  version "2.2.0"
+  resolved "https://registry.yarnpkg.com/parse-json/-/parse-json-2.2.0.tgz#f480f40434ef80741f8469099f8dea18f55a4dc9"
+  dependencies:
+    error-ex "^1.2.0"
+
+path-browserify@0.0.0:
+  version "0.0.0"
+  resolved "https://registry.yarnpkg.com/path-browserify/-/path-browserify-0.0.0.tgz#a0b870729aae214005b7d5032ec2cbbb0fb4451a"
+
+path-exists@^2.0.0:
+  version "2.1.0"
+  resolved "https://registry.yarnpkg.com/path-exists/-/path-exists-2.1.0.tgz#0feb6c64f0fc518d9a754dd5efb62c7022761f4b"
+  dependencies:
+    pinkie-promise "^2.0.0"
+
+path-exists@^3.0.0:
+  version "3.0.0"
+  resolved "https://registry.yarnpkg.com/path-exists/-/path-exists-3.0.0.tgz#ce0ebeaa5f78cb18925ea7d810d7b59b010fd515"
+
+path-is-absolute@^1.0.0:
+  version "1.0.1"
+  resolved "https://registry.yarnpkg.com/path-is-absolute/-/path-is-absolute-1.0.1.tgz#174b9268735534ffbc7ace6bf53a5a9e1b5c5f5f"
+
+path-is-inside@^1.0.1, path-is-inside@^1.0.2:
+  version "1.0.2"
+  resolved "https://registry.yarnpkg.com/path-is-inside/-/path-is-inside-1.0.2.tgz#365417dede44430d1c11af61027facf074bdfc53"
+
+path-key@^2.0.0:
+  version "2.0.1"
+  resolved "https://registry.yarnpkg.com/path-key/-/path-key-2.0.1.tgz#411cadb574c5a140d3a4b1910d40d80cc9f40b40"
+
+path-parse@^1.0.5:
+  version "1.0.5"
+  resolved "https://registry.yarnpkg.com/path-parse/-/path-parse-1.0.5.tgz#3c1adf871ea9cd6c9431b6ea2bd74a0ff055c4c1"
+
+path-type@^2.0.0:
+  version "2.0.0"
+  resolved "https://registry.yarnpkg.com/path-type/-/path-type-2.0.0.tgz#f012ccb8415b7096fc2daa1054c3d72389594c73"
+  dependencies:
+    pify "^2.0.0"
+
+pbkdf2@^3.0.3:
+  version "3.0.12"
+  resolved "https://registry.yarnpkg.com/pbkdf2/-/pbkdf2-3.0.12.tgz#be36785c5067ea48d806ff923288c5f750b6b8a2"
+  dependencies:
+    create-hash "^1.1.2"
+    create-hmac "^1.1.4"
+    ripemd160 "^2.0.1"
+    safe-buffer "^5.0.1"
+    sha.js "^2.4.8"
+
+performance-now@^0.2.0:
+  version "0.2.0"
+  resolved "https://registry.yarnpkg.com/performance-now/-/performance-now-0.2.0.tgz#33ef30c5c77d4ea21c5a53869d91b56d8f2555e5"
+
+pify@^2.0.0, pify@^2.3.0:
+  version "2.3.0"
+  resolved "https://registry.yarnpkg.com/pify/-/pify-2.3.0.tgz#ed141a6ac043a849ea588498e7dca8b15330e90c"
+
+pinkie-promise@^2.0.0:
+  version "2.0.1"
+  resolved "https://registry.yarnpkg.com/pinkie-promise/-/pinkie-promise-2.0.1.tgz#2135d6dfa7a358c069ac9b178776288228450ffa"
+  dependencies:
+    pinkie "^2.0.0"
+
+pinkie@^2.0.0:
+  version "2.0.4"
+  resolved "https://registry.yarnpkg.com/pinkie/-/pinkie-2.0.4.tgz#72556b80cfa0d48a974e80e77248e80ed4f7f870"
+
+pkg-dir@^1.0.0:
+  version "1.0.0"
+  resolved "https://registry.yarnpkg.com/pkg-dir/-/pkg-dir-1.0.0.tgz#7a4b508a8d5bb2d629d447056ff4e9c9314cf3d4"
+  dependencies:
+    find-up "^1.0.0"
+
+pkg-dir@^2.0.0:
+  version "2.0.0"
+  resolved "https://registry.yarnpkg.com/pkg-dir/-/pkg-dir-2.0.0.tgz#f6d5d1109e19d63edf428e0bd57e12777615334b"
+  dependencies:
+    find-up "^2.1.0"
+
+pluralize@^4.0.0:
+  version "4.0.0"
+  resolved "https://registry.yarnpkg.com/pluralize/-/pluralize-4.0.0.tgz#59b708c1c0190a2f692f1c7618c446b052fd1762"
+
+prelude-ls@~1.1.2:
+  version "1.1.2"
+  resolved "https://registry.yarnpkg.com/prelude-ls/-/prelude-ls-1.1.2.tgz#21932a549f5e52ffd9a827f570e04be62a97da54"
+
+preserve@^0.2.0:
+  version "0.2.0"
+  resolved "https://registry.yarnpkg.com/preserve/-/preserve-0.2.0.tgz#815ed1f6ebc65926f865b310c0713bcb3315ce4b"
+
+private@^0.1.6:
+  version "0.1.7"
+  resolved "https://registry.yarnpkg.com/private/-/private-0.1.7.tgz#68ce5e8a1ef0a23bb570cc28537b5332aba63ef1"
+
+process-nextick-args@~1.0.6:
+  version "1.0.7"
+  resolved "https://registry.yarnpkg.com/process-nextick-args/-/process-nextick-args-1.0.7.tgz#150e20b756590ad3f91093f25a4f2ad8bff30ba3"
+
+process@^0.11.0:
+  version "0.11.10"
+  resolved "https://registry.yarnpkg.com/process/-/process-0.11.10.tgz#7332300e840161bda3e69a1d1d91a7d4bc16f182"
+
+progress@^2.0.0:
+  version "2.0.0"
+  resolved "https://registry.yarnpkg.com/progress/-/progress-2.0.0.tgz#8a1be366bf8fc23db2bd23f10c6fe920b4389d1f"
+
+prr@~0.0.0:
+  version "0.0.0"
+  resolved "https://registry.yarnpkg.com/prr/-/prr-0.0.0.tgz#1a84b85908325501411853d0081ee3fa86e2926a"
+
+pseudomap@^1.0.2:
+  version "1.0.2"
+  resolved "https://registry.yarnpkg.com/pseudomap/-/pseudomap-1.0.2.tgz#f052a28da70e618917ef0a8ac34c1ae5a68286b3"
+
+public-encrypt@^4.0.0:
+  version "4.0.0"
+  resolved "https://registry.yarnpkg.com/public-encrypt/-/public-encrypt-4.0.0.tgz#39f699f3a46560dd5ebacbca693caf7c65c18cc6"
+  dependencies:
+    bn.js "^4.1.0"
+    browserify-rsa "^4.0.0"
+    create-hash "^1.1.0"
+    parse-asn1 "^5.0.0"
+    randombytes "^2.0.1"
+
+punycode@1.3.2:
+  version "1.3.2"
+  resolved "https://registry.yarnpkg.com/punycode/-/punycode-1.3.2.tgz#9653a036fb7c1ee42342f2325cceefea3926c48d"
+
+punycode@^1.2.4, punycode@^1.4.1:
+  version "1.4.1"
+  resolved "https://registry.yarnpkg.com/punycode/-/punycode-1.4.1.tgz#c0d5a63b2718800ad8e1eb0fa5269c84dd41845e"
+
+qs@~6.4.0:
+  version "6.4.0"
+  resolved "https://registry.yarnpkg.com/qs/-/qs-6.4.0.tgz#13e26d28ad6b0ffaa91312cd3bf708ed351e7233"
+
+querystring-es3@^0.2.0:
+  version "0.2.1"
+  resolved "https://registry.yarnpkg.com/querystring-es3/-/querystring-es3-0.2.1.tgz#9ec61f79049875707d69414596fd907a4d711e73"
+
+querystring@0.2.0:
+  version "0.2.0"
+  resolved "https://registry.yarnpkg.com/querystring/-/querystring-0.2.0.tgz#b209849203bb25df820da756e747005878521620"
+
+randomatic@^1.1.3:
+  version "1.1.7"
+  resolved "https://registry.yarnpkg.com/randomatic/-/randomatic-1.1.7.tgz#c7abe9cc8b87c0baa876b19fde83fd464797e38c"
+  dependencies:
+    is-number "^3.0.0"
+    kind-of "^4.0.0"
+
+randombytes@^2.0.0, randombytes@^2.0.1:
+  version "2.0.5"
+  resolved "https://registry.yarnpkg.com/randombytes/-/randombytes-2.0.5.tgz#dc009a246b8d09a177b4b7a0ae77bc570f4b1b79"
+  dependencies:
+    safe-buffer "^5.1.0"
+
+rc@^1.1.7:
+  version "1.2.1"
+  resolved "https://registry.yarnpkg.com/rc/-/rc-1.2.1.tgz#2e03e8e42ee450b8cb3dce65be1bf8974e1dfd95"
+  dependencies:
+    deep-extend "~0.4.0"
+    ini "~1.3.0"
+    minimist "^1.2.0"
+    strip-json-comments "~2.0.1"
+
+read-pkg-up@^2.0.0:
+  version "2.0.0"
+  resolved "https://registry.yarnpkg.com/read-pkg-up/-/read-pkg-up-2.0.0.tgz#6b72a8048984e0c41e79510fd5e9fa99b3b549be"
+  dependencies:
+    find-up "^2.0.0"
+    read-pkg "^2.0.0"
+
+read-pkg@^2.0.0:
+  version "2.0.0"
+  resolved "https://registry.yarnpkg.com/read-pkg/-/read-pkg-2.0.0.tgz#8ef1c0623c6a6db0dc6713c4bfac46332b2368f8"
+  dependencies:
+    load-json-file "^2.0.0"
+    normalize-package-data "^2.3.2"
+    path-type "^2.0.0"
+
+readable-stream@^2.0.1, readable-stream@^2.0.2, readable-stream@^2.0.5, readable-stream@^2.0.6, readable-stream@^2.1.4, readable-stream@^2.2.2, readable-stream@^2.2.6:
+  version "2.3.3"
+  resolved "https://registry.yarnpkg.com/readable-stream/-/readable-stream-2.3.3.tgz#368f2512d79f9d46fdfc71349ae7878bbc1eb95c"
+  dependencies:
+    core-util-is "~1.0.0"
+    inherits "~2.0.3"
+    isarray "~1.0.0"
+    process-nextick-args "~1.0.6"
+    safe-buffer "~5.1.1"
+    string_decoder "~1.0.3"
+    util-deprecate "~1.0.1"
+
+readdirp@^2.0.0:
+  version "2.1.0"
+  resolved "https://registry.yarnpkg.com/readdirp/-/readdirp-2.1.0.tgz#4ed0ad060df3073300c48440373f72d1cc642d78"
+  dependencies:
+    graceful-fs "^4.1.2"
+    minimatch "^3.0.2"
+    readable-stream "^2.0.2"
+    set-immediate-shim "^1.0.1"
+
+regenerate@^1.2.1:
+  version "1.3.2"
+  resolved "https://registry.yarnpkg.com/regenerate/-/regenerate-1.3.2.tgz#d1941c67bad437e1be76433add5b385f95b19260"
+
+regenerator-runtime@^0.10.0:
+  version "0.10.5"
+  resolved "https://registry.yarnpkg.com/regenerator-runtime/-/regenerator-runtime-0.10.5.tgz#336c3efc1220adcedda2c9fab67b5a7955a33658"
+
+regenerator-transform@0.9.11:
+  version "0.9.11"
+  resolved "https://registry.yarnpkg.com/regenerator-transform/-/regenerator-transform-0.9.11.tgz#3a7d067520cb7b7176769eb5ff868691befe1283"
+  dependencies:
+    babel-runtime "^6.18.0"
+    babel-types "^6.19.0"
+    private "^0.1.6"
+
+regex-cache@^0.4.2:
+  version "0.4.3"
+  resolved "https://registry.yarnpkg.com/regex-cache/-/regex-cache-0.4.3.tgz#9b1a6c35d4d0dfcef5711ae651e8e9d3d7114145"
+  dependencies:
+    is-equal-shallow "^0.1.3"
+    is-primitive "^2.0.0"
+
+regexpu-core@^2.0.0:
+  version "2.0.0"
+  resolved "https://registry.yarnpkg.com/regexpu-core/-/regexpu-core-2.0.0.tgz#49d038837b8dcf8bfa5b9a42139938e6ea2ae240"
+  dependencies:
+    regenerate "^1.2.1"
+    regjsgen "^0.2.0"
+    regjsparser "^0.1.4"
+
+regjsgen@^0.2.0:
+  version "0.2.0"
+  resolved "https://registry.yarnpkg.com/regjsgen/-/regjsgen-0.2.0.tgz#6c016adeac554f75823fe37ac05b92d5a4edb1f7"
+
+regjsparser@^0.1.4:
+  version "0.1.5"
+  resolved "https://registry.yarnpkg.com/regjsparser/-/regjsparser-0.1.5.tgz#7ee8f84dc6fa792d3fd0ae228d24bd949ead205c"
+  dependencies:
+    jsesc "~0.5.0"
+
+remove-trailing-separator@^1.0.1:
+  version "1.0.2"
+  resolved "https://registry.yarnpkg.com/remove-trailing-separator/-/remove-trailing-separator-1.0.2.tgz#69b062d978727ad14dc6b56ba4ab772fd8d70511"
+
+repeat-element@^1.1.2:
+  version "1.1.2"
+  resolved "https://registry.yarnpkg.com/repeat-element/-/repeat-element-1.1.2.tgz#ef089a178d1483baae4d93eb98b4f9e4e11d990a"
+
+repeat-string@^1.5.2:
+  version "1.6.1"
+  resolved "https://registry.yarnpkg.com/repeat-string/-/repeat-string-1.6.1.tgz#8dcae470e1c88abc2d600fff4a776286da75e637"
+
+repeating@^2.0.0:
+  version "2.0.1"
+  resolved "https://registry.yarnpkg.com/repeating/-/repeating-2.0.1.tgz#5214c53a926d3552707527fbab415dbc08d06dda"
+  dependencies:
+    is-finite "^1.0.0"
+
+request@^2.81.0:
+  version "2.81.0"
+  resolved "https://registry.yarnpkg.com/request/-/request-2.81.0.tgz#c6928946a0e06c5f8d6f8a9333469ffda46298a0"
+  dependencies:
+    aws-sign2 "~0.6.0"
+    aws4 "^1.2.1"
+    caseless "~0.12.0"
+    combined-stream "~1.0.5"
+    extend "~3.0.0"
+    forever-agent "~0.6.1"
+    form-data "~2.1.1"
+    har-validator "~4.2.1"
+    hawk "~3.1.3"
+    http-signature "~1.1.0"
+    is-typedarray "~1.0.0"
+    isstream "~0.1.2"
+    json-stringify-safe "~5.0.1"
+    mime-types "~2.1.7"
+    oauth-sign "~0.8.1"
+    performance-now "^0.2.0"
+    qs "~6.4.0"
+    safe-buffer "^5.0.1"
+    stringstream "~0.0.4"
+    tough-cookie "~2.3.0"
+    tunnel-agent "^0.6.0"
+    uuid "^3.0.0"
+
+require-directory@^2.1.1:
+  version "2.1.1"
+  resolved "https://registry.yarnpkg.com/require-directory/-/require-directory-2.1.1.tgz#8c64ad5fd30dab1c976e2344ffe7f792a6a6df42"
+
+require-main-filename@^1.0.1:
+  version "1.0.1"
+  resolved "https://registry.yarnpkg.com/require-main-filename/-/require-main-filename-1.0.1.tgz#97f717b69d48784f5f526a6c5aa8ffdda055a4d1"
+
+require-uncached@^1.0.3:
+  version "1.0.3"
+  resolved "https://registry.yarnpkg.com/require-uncached/-/require-uncached-1.0.3.tgz#4e0d56d6c9662fd31e43011c4b95aa49955421d3"
+  dependencies:
+    caller-path "^0.1.0"
+    resolve-from "^1.0.0"
+
+resolve-from@^1.0.0:
+  version "1.0.1"
+  resolved "https://registry.yarnpkg.com/resolve-from/-/resolve-from-1.0.1.tgz#26cbfe935d1aeeeabb29bc3fe5aeb01e93d44226"
+
+resolve@^1.2.0:
+  version "1.4.0"
+  resolved "https://registry.yarnpkg.com/resolve/-/resolve-1.4.0.tgz#a75be01c53da25d934a98ebd0e4c4a7312f92a86"
+  dependencies:
+    path-parse "^1.0.5"
+
+restore-cursor@^2.0.0:
+  version "2.0.0"
+  resolved "https://registry.yarnpkg.com/restore-cursor/-/restore-cursor-2.0.0.tgz#9f7ee287f82fd326d4fd162923d62129eee0dfaf"
+  dependencies:
+    onetime "^2.0.0"
+    signal-exit "^3.0.2"
+
+right-align@^0.1.1:
+  version "0.1.3"
+  resolved "https://registry.yarnpkg.com/right-align/-/right-align-0.1.3.tgz#61339b722fe6a3515689210d24e14c96148613ef"
+  dependencies:
+    align-text "^0.1.1"
+
+rimraf@2, rimraf@^2.2.8, rimraf@^2.5.1, rimraf@^2.6.1:
+  version "2.6.1"
+  resolved "https://registry.yarnpkg.com/rimraf/-/rimraf-2.6.1.tgz#c2338ec643df7a1b7fe5c54fa86f57428a55f33d"
+  dependencies:
+    glob "^7.0.5"
+
+ripemd160@^2.0.0, ripemd160@^2.0.1:
+  version "2.0.1"
+  resolved "https://registry.yarnpkg.com/ripemd160/-/ripemd160-2.0.1.tgz#0f4584295c53a3628af7e6d79aca21ce57d1c6e7"
+  dependencies:
+    hash-base "^2.0.0"
+    inherits "^2.0.1"
+
+run-async@^2.2.0:
+  version "2.3.0"
+  resolved "https://registry.yarnpkg.com/run-async/-/run-async-2.3.0.tgz#0371ab4ae0bdd720d4166d7dfda64ff7a445a6c0"
+  dependencies:
+    is-promise "^2.1.0"
+
+rx-lite-aggregates@^4.0.8:
+  version "4.0.8"
+  resolved "https://registry.yarnpkg.com/rx-lite-aggregates/-/rx-lite-aggregates-4.0.8.tgz#753b87a89a11c95467c4ac1626c4efc4e05c67be"
+  dependencies:
+    rx-lite "*"
+
+rx-lite@*, rx-lite@^4.0.8:
+  version "4.0.8"
+  resolved "https://registry.yarnpkg.com/rx-lite/-/rx-lite-4.0.8.tgz#0b1e11af8bc44836f04a6407e92da42467b79444"
+
+safe-buffer@^5.0.1, safe-buffer@^5.1.0, safe-buffer@~5.1.0, safe-buffer@~5.1.1:
+  version "5.1.1"
+  resolved "https://registry.yarnpkg.com/safe-buffer/-/safe-buffer-5.1.1.tgz#893312af69b2123def71f57889001671eeb2c853"
+
+"semver@2 || 3 || 4 || 5", semver@^5.3.0:
+  version "5.4.1"
+  resolved "https://registry.yarnpkg.com/semver/-/semver-5.4.1.tgz#e059c09d8571f0540823733433505d3a2f00b18e"
+
+set-blocking@^2.0.0, set-blocking@~2.0.0:
+  version "2.0.0"
+  resolved "https://registry.yarnpkg.com/set-blocking/-/set-blocking-2.0.0.tgz#045f9782d011ae9a6803ddd382b24392b3d890f7"
+
+set-immediate-shim@^1.0.1:
+  version "1.0.1"
+  resolved "https://registry.yarnpkg.com/set-immediate-shim/-/set-immediate-shim-1.0.1.tgz#4b2b1b27eb808a9f8dcc481a58e5e56f599f3f61"
+
+setimmediate@^1.0.4:
+  version "1.0.5"
+  resolved "https://registry.yarnpkg.com/setimmediate/-/setimmediate-1.0.5.tgz#290cbb232e306942d7d7ea9b83732ab7856f8285"
+
+sha.js@^2.4.0, sha.js@^2.4.8:
+  version "2.4.8"
+  resolved "https://registry.yarnpkg.com/sha.js/-/sha.js-2.4.8.tgz#37068c2c476b6baf402d14a49c67f597921f634f"
+  dependencies:
+    inherits "^2.0.1"
+
+shebang-command@^1.2.0:
+  version "1.2.0"
+  resolved "https://registry.yarnpkg.com/shebang-command/-/shebang-command-1.2.0.tgz#44aac65b695b03398968c39f363fee5deafdf1ea"
+  dependencies:
+    shebang-regex "^1.0.0"
+
+shebang-regex@^1.0.0:
+  version "1.0.0"
+  resolved "https://registry.yarnpkg.com/shebang-regex/-/shebang-regex-1.0.0.tgz#da42f49740c0b42db2ca9728571cb190c98efea3"
+
+signal-exit@^3.0.0, signal-exit@^3.0.2:
+  version "3.0.2"
+  resolved "https://registry.yarnpkg.com/signal-exit/-/signal-exit-3.0.2.tgz#b5fdc08f1287ea1178628e415e25132b73646c6d"
+
+slash@^1.0.0:
+  version "1.0.0"
+  resolved "https://registry.yarnpkg.com/slash/-/slash-1.0.0.tgz#c41f2f6c39fc16d1cd17ad4b5d896114ae470d55"
+
+slice-ansi@0.0.4:
+  version "0.0.4"
+  resolved "https://registry.yarnpkg.com/slice-ansi/-/slice-ansi-0.0.4.tgz#edbf8903f66f7ce2f8eafd6ceed65e264c831b35"
+
+sntp@1.x.x:
+  version "1.0.9"
+  resolved "https://registry.yarnpkg.com/sntp/-/sntp-1.0.9.tgz#6541184cc90aeea6c6e7b35e2659082443c66198"
+  dependencies:
+    hoek "2.x.x"
+
+source-list-map@^2.0.0:
+  version "2.0.0"
+  resolved "https://registry.yarnpkg.com/source-list-map/-/source-list-map-2.0.0.tgz#aaa47403f7b245a92fbc97ea08f250d6087ed085"
+
+source-map-support@^0.4.2:
+  version "0.4.15"
+  resolved "https://registry.yarnpkg.com/source-map-support/-/source-map-support-0.4.15.tgz#03202df65c06d2bd8c7ec2362a193056fef8d3b1"
+  dependencies:
+    source-map "^0.5.6"
+
+source-map@^0.5.0, source-map@^0.5.3, source-map@^0.5.6, source-map@~0.5.1, source-map@~0.5.3:
+  version "0.5.6"
+  resolved "https://registry.yarnpkg.com/source-map/-/source-map-0.5.6.tgz#75ce38f52bf0733c5a7f0c118d81334a2bb5f412"
+
+spark-md5@^3.0.0:
+  version "3.0.0"
+  resolved "https://registry.yarnpkg.com/spark-md5/-/spark-md5-3.0.0.tgz#3722227c54e2faf24b1dc6d933cc144e6f71bfef"
+
+spdx-correct@~1.0.0:
+  version "1.0.2"
+  resolved "https://registry.yarnpkg.com/spdx-correct/-/spdx-correct-1.0.2.tgz#4b3073d933ff51f3912f03ac5519498a4150db40"
+  dependencies:
+    spdx-license-ids "^1.0.2"
+
+spdx-expression-parse@~1.0.0:
+  version "1.0.4"
+  resolved "https://registry.yarnpkg.com/spdx-expression-parse/-/spdx-expression-parse-1.0.4.tgz#9bdf2f20e1f40ed447fbe273266191fced51626c"
+
+spdx-license-ids@^1.0.2:
+  version "1.2.2"
+  resolved "https://registry.yarnpkg.com/spdx-license-ids/-/spdx-license-ids-1.2.2.tgz#c9df7a3424594ade6bd11900d596696dc06bac57"
+
+sprintf-js@~1.0.2:
+  version "1.0.3"
+  resolved "https://registry.yarnpkg.com/sprintf-js/-/sprintf-js-1.0.3.tgz#04e6926f662895354f3dd015203633b857297e2c"
+
+sshpk@^1.7.0:
+  version "1.13.1"
+  resolved "https://registry.yarnpkg.com/sshpk/-/sshpk-1.13.1.tgz#512df6da6287144316dc4c18fe1cf1d940739be3"
+  dependencies:
+    asn1 "~0.2.3"
+    assert-plus "^1.0.0"
+    dashdash "^1.12.0"
+    getpass "^0.1.1"
+  optionalDependencies:
+    bcrypt-pbkdf "^1.0.0"
+    ecc-jsbn "~0.1.1"
+    jsbn "~0.1.0"
+    tweetnacl "~0.14.0"
+
+stream-browserify@^2.0.1:
+  version "2.0.1"
+  resolved "https://registry.yarnpkg.com/stream-browserify/-/stream-browserify-2.0.1.tgz#66266ee5f9bdb9940a4e4514cafb43bb71e5c9db"
+  dependencies:
+    inherits "~2.0.1"
+    readable-stream "^2.0.2"
+
+stream-http@^2.3.1:
+  version "2.7.2"
+  resolved "https://registry.yarnpkg.com/stream-http/-/stream-http-2.7.2.tgz#40a050ec8dc3b53b33d9909415c02c0bf1abfbad"
+  dependencies:
+    builtin-status-codes "^3.0.0"
+    inherits "^2.0.1"
+    readable-stream "^2.2.6"
+    to-arraybuffer "^1.0.0"
+    xtend "^4.0.0"
+
+string-width@^1.0.1, string-width@^1.0.2:
+  version "1.0.2"
+  resolved "https://registry.yarnpkg.com/string-width/-/string-width-1.0.2.tgz#118bdf5b8cdc51a2a7e70d211e07e2b0b9b107d3"
+  dependencies:
+    code-point-at "^1.0.0"
+    is-fullwidth-code-point "^1.0.0"
+    strip-ansi "^3.0.0"
+
+string-width@^2.0.0, string-width@^2.1.0:
+  version "2.1.1"
+  resolved "https://registry.yarnpkg.com/string-width/-/string-width-2.1.1.tgz#ab93f27a8dc13d28cac815c462143a6d9012ae9e"
+  dependencies:
+    is-fullwidth-code-point "^2.0.0"
+    strip-ansi "^4.0.0"
+
+string_decoder@^0.10.25:
+  version "0.10.31"
+  resolved "https://registry.yarnpkg.com/string_decoder/-/string_decoder-0.10.31.tgz#62e203bc41766c6c28c9fc84301dab1c5310fa94"
+
+string_decoder@~1.0.3:
+  version "1.0.3"
+  resolved "https://registry.yarnpkg.com/string_decoder/-/string_decoder-1.0.3.tgz#0fc67d7c141825de94282dd536bec6b9bce860ab"
+  dependencies:
+    safe-buffer "~5.1.0"
+
+stringstream@~0.0.4:
+  version "0.0.5"
+  resolved "https://registry.yarnpkg.com/stringstream/-/stringstream-0.0.5.tgz#4e484cd4de5a0bbbee18e46307710a8a81621878"
+
+strip-ansi@^3.0.0, strip-ansi@^3.0.1:
+  version "3.0.1"
+  resolved "https://registry.yarnpkg.com/strip-ansi/-/strip-ansi-3.0.1.tgz#6a385fb8853d952d5ff05d0e8aaf94278dc63dcf"
+  dependencies:
+    ansi-regex "^2.0.0"
+
+strip-ansi@^4.0.0:
+  version "4.0.0"
+  resolved "https://registry.yarnpkg.com/strip-ansi/-/strip-ansi-4.0.0.tgz#a8479022eb1ac368a871389b635262c505ee368f"
+  dependencies:
+    ansi-regex "^3.0.0"
+
+strip-bom@^3.0.0:
+  version "3.0.0"
+  resolved "https://registry.yarnpkg.com/strip-bom/-/strip-bom-3.0.0.tgz#2334c18e9c759f7bdd56fdef7e9ae3d588e68ed3"
+
+strip-eof@^1.0.0:
+  version "1.0.0"
+  resolved "https://registry.yarnpkg.com/strip-eof/-/strip-eof-1.0.0.tgz#bb43ff5598a6eb05d89b59fcd129c983313606bf"
+
+strip-json-comments@~2.0.1:
+  version "2.0.1"
+  resolved "https://registry.yarnpkg.com/strip-json-comments/-/strip-json-comments-2.0.1.tgz#3c531942e908c2697c0ec344858c286c7ca0a60a"
+
+supports-color@^2.0.0:
+  version "2.0.0"
+  resolved "https://registry.yarnpkg.com/supports-color/-/supports-color-2.0.0.tgz#535d045ce6b6363fa40117084629995e9df324c7"
+
+supports-color@^4.0.0, supports-color@^4.2.1:
+  version "4.2.1"
+  resolved "https://registry.yarnpkg.com/supports-color/-/supports-color-4.2.1.tgz#65a4bb2631e90e02420dba5554c375a4754bb836"
+  dependencies:
+    has-flag "^2.0.0"
+
+table@^4.0.1:
+  version "4.0.1"
+  resolved "https://registry.yarnpkg.com/table/-/table-4.0.1.tgz#a8116c133fac2c61f4a420ab6cdf5c4d61f0e435"
+  dependencies:
+    ajv "^4.7.0"
+    ajv-keywords "^1.0.0"
+    chalk "^1.1.1"
+    lodash "^4.0.0"
+    slice-ansi "0.0.4"
+    string-width "^2.0.0"
+
+tapable@^0.2.7:
+  version "0.2.7"
+  resolved "https://registry.yarnpkg.com/tapable/-/tapable-0.2.7.tgz#e46c0daacbb2b8a98b9b0cea0f4052105817ed5c"
+
+tar-pack@^3.4.0:
+  version "3.4.0"
+  resolved "https://registry.yarnpkg.com/tar-pack/-/tar-pack-3.4.0.tgz#23be2d7f671a8339376cbdb0b8fe3fdebf317984"
+  dependencies:
+    debug "^2.2.0"
+    fstream "^1.0.10"
+    fstream-ignore "^1.0.5"
+    once "^1.3.3"
+    readable-stream "^2.1.4"
+    rimraf "^2.5.1"
+    tar "^2.2.1"
+    uid-number "^0.0.6"
+
+tar@^2.2.1:
+  version "2.2.1"
+  resolved "https://registry.yarnpkg.com/tar/-/tar-2.2.1.tgz#8e4d2a256c0e2185c6b18ad694aec968b83cb1d1"
+  dependencies:
+    block-stream "*"
+    fstream "^1.0.2"
+    inherits "2"
+
+text-table@~0.2.0:
+  version "0.2.0"
+  resolved "https://registry.yarnpkg.com/text-table/-/text-table-0.2.0.tgz#7f5ee823ae805207c00af2df4a84ec3fcfa570b4"
+
+through@^2.3.6:
+  version "2.3.8"
+  resolved "https://registry.yarnpkg.com/through/-/through-2.3.8.tgz#0dd4c9ffaabc357960b1b724115d7e0e86a2e1f5"
+
+timers-browserify@^2.0.2:
+  version "2.0.2"
+  resolved "https://registry.yarnpkg.com/timers-browserify/-/timers-browserify-2.0.2.tgz#ab4883cf597dcd50af211349a00fbca56ac86b86"
+  dependencies:
+    setimmediate "^1.0.4"
+
+tmp@^0.0.31:
+  version "0.0.31"
+  resolved "https://registry.yarnpkg.com/tmp/-/tmp-0.0.31.tgz#8f38ab9438e17315e5dbd8b3657e8bfb277ae4a7"
+  dependencies:
+    os-tmpdir "~1.0.1"
+
+to-arraybuffer@^1.0.0:
+  version "1.0.1"
+  resolved "https://registry.yarnpkg.com/to-arraybuffer/-/to-arraybuffer-1.0.1.tgz#7d229b1fcc637e466ca081180836a7aabff83f43"
+
+to-fast-properties@^1.0.1:
+  version "1.0.3"
+  resolved "https://registry.yarnpkg.com/to-fast-properties/-/to-fast-properties-1.0.3.tgz#b83571fa4d8c25b82e231b06e3a3055de4ca1a47"
+
+tough-cookie@~2.3.0:
+  version "2.3.2"
+  resolved "https://registry.yarnpkg.com/tough-cookie/-/tough-cookie-2.3.2.tgz#f081f76e4c85720e6c37a5faced737150d84072a"
+  dependencies:
+    punycode "^1.4.1"
+
+trim-right@^1.0.1:
+  version "1.0.1"
+  resolved "https://registry.yarnpkg.com/trim-right/-/trim-right-1.0.1.tgz#cb2e1203067e0c8de1f614094b9fe45704ea6003"
+
+tryit@^1.0.1:
+  version "1.0.3"
+  resolved "https://registry.yarnpkg.com/tryit/-/tryit-1.0.3.tgz#393be730a9446fd1ead6da59a014308f36c289cb"
+
+tty-browserify@0.0.0:
+  version "0.0.0"
+  resolved "https://registry.yarnpkg.com/tty-browserify/-/tty-browserify-0.0.0.tgz#a157ba402da24e9bf957f9aa69d524eed42901a6"
+
+tunnel-agent@^0.6.0:
+  version "0.6.0"
+  resolved "https://registry.yarnpkg.com/tunnel-agent/-/tunnel-agent-0.6.0.tgz#27a5dea06b36b04a0a9966774b290868f0fc40fd"
+  dependencies:
+    safe-buffer "^5.0.1"
+
+tweetnacl@^0.14.3, tweetnacl@~0.14.0:
+  version "0.14.5"
+  resolved "https://registry.yarnpkg.com/tweetnacl/-/tweetnacl-0.14.5.tgz#5ae68177f192d4456269d108afa93ff8743f4f64"
+
+type-check@~0.3.2:
+  version "0.3.2"
+  resolved "https://registry.yarnpkg.com/type-check/-/type-check-0.3.2.tgz#5884cab512cf1d355e3fb784f30804b2b520db72"
+  dependencies:
+    prelude-ls "~1.1.2"
+
+typedarray@^0.0.6:
+  version "0.0.6"
+  resolved "https://registry.yarnpkg.com/typedarray/-/typedarray-0.0.6.tgz#867ac74e3864187b1d3d47d996a78ec5c8830777"
+
+uglify-js@^2.8.29:
+  version "2.8.29"
+  resolved "https://registry.yarnpkg.com/uglify-js/-/uglify-js-2.8.29.tgz#29c5733148057bb4e1f75df35b7a9cb72e6a59dd"
+  dependencies:
+    source-map "~0.5.1"
+    yargs "~3.10.0"
+  optionalDependencies:
+    uglify-to-browserify "~1.0.0"
+
+uglify-to-browserify@~1.0.0:
+  version "1.0.2"
+  resolved "https://registry.yarnpkg.com/uglify-to-browserify/-/uglify-to-browserify-1.0.2.tgz#6e0924d6bda6b5afe349e39a6d632850a0f882b7"
+
+uglifyjs-webpack-plugin@^0.4.6:
+  version "0.4.6"
+  resolved "https://registry.yarnpkg.com/uglifyjs-webpack-plugin/-/uglifyjs-webpack-plugin-0.4.6.tgz#b951f4abb6bd617e66f63eb891498e391763e309"
+  dependencies:
+    source-map "^0.5.6"
+    uglify-js "^2.8.29"
+    webpack-sources "^1.0.1"
+
+uid-number@^0.0.6:
+  version "0.0.6"
+  resolved "https://registry.yarnpkg.com/uid-number/-/uid-number-0.0.6.tgz#0ea10e8035e8eb5b8e4449f06da1c730663baa81"
+
+url@^0.11.0:
+  version "0.11.0"
+  resolved "https://registry.yarnpkg.com/url/-/url-0.11.0.tgz#3838e97cfc60521eb73c525a8e55bfdd9e2e28f1"
+  dependencies:
+    punycode "1.3.2"
+    querystring "0.2.0"
+
+util-deprecate@~1.0.1:
+  version "1.0.2"
+  resolved "https://registry.yarnpkg.com/util-deprecate/-/util-deprecate-1.0.2.tgz#450d4dc9fa70de732762fbd2d4a28981419a0ccf"
+
+util@0.10.3, util@^0.10.3:
+  version "0.10.3"
+  resolved "https://registry.yarnpkg.com/util/-/util-0.10.3.tgz#7afb1afe50805246489e3db7fe0ed379336ac0f9"
+  dependencies:
+    inherits "2.0.1"
+
+uuid@^3.0.0:
+  version "3.1.0"
+  resolved "https://registry.yarnpkg.com/uuid/-/uuid-3.1.0.tgz#3dd3d3e790abc24d7b0d3a034ffababe28ebbc04"
+
+validate-npm-package-license@^3.0.1:
+  version "3.0.1"
+  resolved "https://registry.yarnpkg.com/validate-npm-package-license/-/validate-npm-package-license-3.0.1.tgz#2804babe712ad3379459acfbe24746ab2c303fbc"
+  dependencies:
+    spdx-correct "~1.0.0"
+    spdx-expression-parse "~1.0.0"
+
+verror@1.3.6:
+  version "1.3.6"
+  resolved "https://registry.yarnpkg.com/verror/-/verror-1.3.6.tgz#cff5df12946d297d2baaefaa2689e25be01c005c"
+  dependencies:
+    extsprintf "1.0.2"
+
+vm-browserify@0.0.4:
+  version "0.0.4"
+  resolved "https://registry.yarnpkg.com/vm-browserify/-/vm-browserify-0.0.4.tgz#5d7ea45bbef9e4a6ff65f95438e0a87c357d5a73"
+  dependencies:
+    indexof "0.0.1"
+
+watchpack@^1.4.0:
+  version "1.4.0"
+  resolved "https://registry.yarnpkg.com/watchpack/-/watchpack-1.4.0.tgz#4a1472bcbb952bd0a9bb4036801f954dfb39faac"
+  dependencies:
+    async "^2.1.2"
+    chokidar "^1.7.0"
+    graceful-fs "^4.1.2"
+
+webpack-sources@^1.0.1:
+  version "1.0.1"
+  resolved "https://registry.yarnpkg.com/webpack-sources/-/webpack-sources-1.0.1.tgz#c7356436a4d13123be2e2426a05d1dad9cbe65cf"
+  dependencies:
+    source-list-map "^2.0.0"
+    source-map "~0.5.3"
+
+webpack@^3.4.0:
+  version "3.4.0"
+  resolved "https://registry.yarnpkg.com/webpack/-/webpack-3.4.0.tgz#e9465b660ad79dd2d33874d968b31746ea9a8e63"
+  dependencies:
+    acorn "^5.0.0"
+    acorn-dynamic-import "^2.0.0"
+    ajv "^5.1.5"
+    ajv-keywords "^2.0.0"
+    async "^2.1.2"
+    enhanced-resolve "^3.4.0"
+    escope "^3.6.0"
+    interpret "^1.0.0"
+    json-loader "^0.5.4"
+    json5 "^0.5.1"
+    loader-runner "^2.3.0"
+    loader-utils "^1.1.0"
+    memory-fs "~0.4.1"
+    mkdirp "~0.5.0"
+    node-libs-browser "^2.0.0"
+    source-map "^0.5.3"
+    supports-color "^4.2.1"
+    tapable "^0.2.7"
+    uglifyjs-webpack-plugin "^0.4.6"
+    watchpack "^1.4.0"
+    webpack-sources "^1.0.1"
+    yargs "^8.0.2"
+
+which-module@^2.0.0:
+  version "2.0.0"
+  resolved "https://registry.yarnpkg.com/which-module/-/which-module-2.0.0.tgz#d9ef07dce77b9902b8a3a8fa4b31c3e3f7e6e87a"
+
+which@^1.2.9:
+  version "1.2.14"
+  resolved "https://registry.yarnpkg.com/which/-/which-1.2.14.tgz#9a87c4378f03e827cecaf1acdf56c736c01c14e5"
+  dependencies:
+    isexe "^2.0.0"
+
+wide-align@^1.1.0:
+  version "1.1.2"
+  resolved "https://registry.yarnpkg.com/wide-align/-/wide-align-1.1.2.tgz#571e0f1b0604636ebc0dfc21b0339bbe31341710"
+  dependencies:
+    string-width "^1.0.2"
+
+window-size@0.1.0:
+  version "0.1.0"
+  resolved "https://registry.yarnpkg.com/window-size/-/window-size-0.1.0.tgz#5438cd2ea93b202efa3a19fe8887aee7c94f9c9d"
+
+wordwrap@0.0.2:
+  version "0.0.2"
+  resolved "https://registry.yarnpkg.com/wordwrap/-/wordwrap-0.0.2.tgz#b79669bb42ecb409f83d583cad52ca17eaa1643f"
+
+wordwrap@~1.0.0:
+  version "1.0.0"
+  resolved "https://registry.yarnpkg.com/wordwrap/-/wordwrap-1.0.0.tgz#27584810891456a4171c8d0226441ade90cbcaeb"
+
+wrap-ansi@^2.0.0:
+  version "2.1.0"
+  resolved "https://registry.yarnpkg.com/wrap-ansi/-/wrap-ansi-2.1.0.tgz#d8fc3d284dd05794fe84973caecdd1cf824fdd85"
+  dependencies:
+    string-width "^1.0.1"
+    strip-ansi "^3.0.1"
+
+wrappy@1:
+  version "1.0.2"
+  resolved "https://registry.yarnpkg.com/wrappy/-/wrappy-1.0.2.tgz#b5243d8f3ec1aa35f1364605bc0d1036e30ab69f"
+
+write@^0.2.1:
+  version "0.2.1"
+  resolved "https://registry.yarnpkg.com/write/-/write-0.2.1.tgz#5fc03828e264cea3fe91455476f7a3c566cb0757"
+  dependencies:
+    mkdirp "^0.5.1"
+
+xtend@^4.0.0:
+  version "4.0.1"
+  resolved "https://registry.yarnpkg.com/xtend/-/xtend-4.0.1.tgz#a5c6d532be656e23db820efb943a1f04998d63af"
+
+y18n@^3.2.1:
+  version "3.2.1"
+  resolved "https://registry.yarnpkg.com/y18n/-/y18n-3.2.1.tgz#6d15fba884c08679c0d77e88e7759e811e07fa41"
+
+yallist@^2.1.2:
+  version "2.1.2"
+  resolved "https://registry.yarnpkg.com/yallist/-/yallist-2.1.2.tgz#1c11f9218f076089a47dd512f93c6699a6a81d52"
+
+yargs-parser@^7.0.0:
+  version "7.0.0"
+  resolved "https://registry.yarnpkg.com/yargs-parser/-/yargs-parser-7.0.0.tgz#8d0ac42f16ea55debd332caf4c4038b3e3f5dfd9"
+  dependencies:
+    camelcase "^4.1.0"
+
+yargs@^8.0.2:
+  version "8.0.2"
+  resolved "https://registry.yarnpkg.com/yargs/-/yargs-8.0.2.tgz#6299a9055b1cefc969ff7e79c1d918dceb22c360"
+  dependencies:
+    camelcase "^4.1.0"
+    cliui "^3.2.0"
+    decamelize "^1.1.1"
+    get-caller-file "^1.0.1"
+    os-locale "^2.0.0"
+    read-pkg-up "^2.0.0"
+    require-directory "^2.1.1"
+    require-main-filename "^1.0.1"
+    set-blocking "^2.0.0"
+    string-width "^2.0.0"
+    which-module "^2.0.0"
+    y18n "^3.2.1"
+    yargs-parser "^7.0.0"
+
+yargs@~3.10.0:
+  version "3.10.0"
+  resolved "https://registry.yarnpkg.com/yargs/-/yargs-3.10.0.tgz#f7ee7bd857dd7c1d2d38c0e74efbd681d1431fd1"
+  dependencies:
+    camelcase "^1.0.2"
+    cliui "^2.1.0"
+    decamelize "^1.0.0"
+    window-size "0.1.0"
diff --git a/activesupport/CHANGELOG.md b/activesupport/CHANGELOG.md
index d9f23c55ba..fccaeb5d32 100644
--- a/activesupport/CHANGELOG.md
+++ b/activesupport/CHANGELOG.md
@@ -1,64 +1,486 @@
-*   Remove deprecated arguments in `assert_nothing_raised`.
+*   Allow the hash function used to generate non-sensitive digests, such as the
+    ETag header, to be specified with `config.active_support.hash_digest_class`.
 
-    *Rafel Mendonça França*
+    The object provided must respond to `#hexdigest`, e.g. `Digest::SHA1`.
 
-*   `Date.to_s` doesn't produce too many spaces. For example, `to_s(:short)`
-    will now produce `01 Feb` instead of ` 1 Feb`.
+    *Dmitri Dolguikh*
+ 
+## Rails 5.2.0.beta2 (November 28, 2017) ##
 
-    Fixes #25251.
+*   No changes.
 
-    *Sean Griffin*
 
-*   Introduce Module#delegate_missing_to.
+## Rails 5.2.0.beta1 (November 27, 2017) ##
 
-    When building a decorator, a common pattern emerges:
+*   Changed default behaviour of `ActiveSupport::SecurityUtils.secure_compare`,
+    to make it not leak length information even for variable length string.
 
-        class Partition
-          def initialize(first_event)
-            @events = [ first_event ]
-          end
+    Renamed old `ActiveSupport::SecurityUtils.secure_compare` to `fixed_length_secure_compare`,
+    and started raising `ArgumentError` in case of length mismatch of passed strings.
 
-          def people
-            if @events.first.detail.people.any?
-              @events.collect { |e| Array(e.detail.people) }.flatten.uniq
-            else
-              @events.collect(&:creator).uniq
-            end
-          end
+    *Vipul A M*
 
-          private
-            def respond_to_missing?(name, include_private = false)
-              @events.respond_to?(name, include_private)
-            end
+*   Make `ActiveSupport::TimeZone.all` return only time zones that are in
+    `ActiveSupport::TimeZone::MAPPING`.
 
-            def method_missing(method, *args, &block)
-              @events.send(method, *args, &block)
-            end
-        end
+    Fixes #7245.
 
-    With `Module#delegate_missing_to`, the above is condensed to:
+    *Chris LaRose*
 
-        class Partition
-          delegate_missing_to :@events
+*   MemCacheStore: Support expiring counters.
 
-          def initialize(first_event)
-            @events = [ first_event ]
-          end
+    Pass `expires_in: [seconds]` to `#increment` and `#decrement` options
+    to set the Memcached TTL (time-to-live) if the counter doesn't exist.
+    If the counter exists, Memcached doesn't extend its expiry when it's
+    incremented or decremented.
 
-          def people
-            if @events.first.detail.people.any?
-              @events.collect { |e| Array(e.detail.people) }.flatten.uniq
-            else
-              @events.collect(&:creator).uniq
-            end
-          end
-        end
+    ```
+    Rails.cache.increment("my_counter", 1, expires_in: 2.minutes)
+    ```
 
-    *Genadi Samokovarov*, *DHH*
+    *Takumasa Ochi*
 
-*   Rescuable: If a handler doesn't match the exception, check for handlers
-    matching the exception's cause.
+*   Handle `TZInfo::AmbiguousTime` errors
+
+    Make `ActiveSupport::TimeWithZone` match Ruby's handling of ambiguous
+    times by choosing the later period, e.g.
+
+    Ruby:
+    ```
+    ENV["TZ"] = "Europe/Moscow"
+    Time.local(2014, 10, 26, 1, 0, 0)   # => 2014-10-26 01:00:00 +0300
+    ```
+
+    Before:
+    ```
+    >> "2014-10-26 01:00:00".in_time_zone("Moscow")
+    TZInfo::AmbiguousTime: 26/10/2014 01:00 is an ambiguous local time.
+    ```
+
+    After:
+    ```
+    >> "2014-10-26 01:00:00".in_time_zone("Moscow")
+    => Sun, 26 Oct 2014 01:00:00 MSK +03:00
+    ```
+
+    Fixes #17395.
+
+    *Andrew White*
+
+*   Redis cache store.
+
+    ```
+    # Defaults to `redis://localhost:6379/0`. Only use for dev/test.
+    config.cache_store = :redis_cache_store
+
+    # Supports all common cache store options (:namespace, :compress,
+    # :compress_threshold, :expires_in, :race_condition_ttl) and all
+    # Redis options.
+    cache_password = Rails.application.secrets.redis_cache_password
+    config.cache_store = :redis_cache_store, driver: :hiredis,
+      namespace: 'myapp-cache', compress: true, timeout: 1,
+      url: "redis://:#{cache_password}@myapp-cache-1:6379/0"
+
+    # Supports Redis::Distributed with multiple hosts
+    config.cache_store = :redis_cache_store, driver: :hiredis
+      namespace: 'myapp-cache', compress: true,
+      url: %w[
+        redis://myapp-cache-1:6379/0
+        redis://myapp-cache-1:6380/0
+        redis://myapp-cache-2:6379/0
+        redis://myapp-cache-2:6380/0
+        redis://myapp-cache-3:6379/0
+        redis://myapp-cache-3:6380/0
+      ]
+
+    # Or pass a builder block
+    config.cache_store = :redis_cache_store,
+      namespace: 'myapp-cache', compress: true,
+      redis: -> { Redis.new … }
+    ```
+
+    Deployment note: Take care to use a *dedicated Redis cache* rather
+    than pointing this at your existing Redis server. It won't cope well
+    with mixed usage patterns and it won't expire cache entries by default.
+
+    Redis cache server setup guide: https://redis.io/topics/lru-cache
+
+    *Jeremy Daer*
+
+*   Cache: Enable compression by default for values > 1kB.
+
+    Compression has long been available, but opt-in and at a 16kB threshold.
+    It wasn't enabled by default due to CPU cost. Today it's cheap and typical
+    cache data is eminently compressible, such as HTML or JSON fragments.
+    Compression dramatically reduces Memcached/Redis mem usage, which means
+    the same cache servers can store more data, which means higher hit rates.
+
+    To disable compression, pass `compress: false` to the initializer.
+
+    *Jeremy Daer*
+
+*   Allow `Range#include?` on TWZ ranges
+
+    In #11474 we prevented TWZ ranges being iterated over which matched
+    Ruby's handling of Time ranges and as a consequence `include?`
+    stopped working with both Time ranges and TWZ ranges. However in
+    ruby/ruby@b061634 support was added for `include?` to use `cover?`
+    for 'linear' objects. Since we have no way of making Ruby consider
+    TWZ instances as 'linear' we have to override `Range#include?`.
+
+    Fixes #30799.
+
+    *Andrew White*
+
+*   Fix acronym support in `humanize`
+
+    Acronym inflections are stored with lowercase keys in the hash but
+    the match wasn't being lowercased before being looked up in the hash.
+    This shouldn't have any performance impact because before it would
+    fail to find the acronym and perform the `downcase` operation anyway.
+
+    Fixes #31052.
+
+    *Andrew White*
+
+*   Add same method signature for `Time#prev_year` and `Time#next_year`
+    in accordance with `Date#prev_year`, `Date#next_year`.
+
+    Allows pass argument for `Time#prev_year` and `Time#next_year`.
+
+    Before:
+    ```
+    Time.new(2017, 9, 16, 17, 0).prev_year    # => 2016-09-16 17:00:00 +0300
+    Time.new(2017, 9, 16, 17, 0).prev_year(1)
+    # => ArgumentError: wrong number of arguments (given 1, expected 0)
+
+    Time.new(2017, 9, 16, 17, 0).next_year    # => 2018-09-16 17:00:00 +0300
+    Time.new(2017, 9, 16, 17, 0).next_year(1)
+    # => ArgumentError: wrong number of arguments (given 1, expected 0)
+    ```
+
+    After:
+    ```
+    Time.new(2017, 9, 16, 17, 0).prev_year    # => 2016-09-16 17:00:00 +0300
+    Time.new(2017, 9, 16, 17, 0).prev_year(1) # => 2016-09-16 17:00:00 +0300
+
+    Time.new(2017, 9, 16, 17, 0).next_year    # => 2018-09-16 17:00:00 +0300
+    Time.new(2017, 9, 16, 17, 0).next_year(1) # => 2018-09-16 17:00:00 +0300
+    ```
+
+    *bogdanvlviv*
+
+*   Add same method signature for `Time#prev_month` and `Time#next_month`
+    in accordance with `Date#prev_month`, `Date#next_month`.
+
+    Allows pass argument for `Time#prev_month` and `Time#next_month`.
+
+    Before:
+    ```
+    Time.new(2017, 9, 16, 17, 0).prev_month    # => 2017-08-16 17:00:00 +0300
+    Time.new(2017, 9, 16, 17, 0).prev_month(1)
+    # => ArgumentError: wrong number of arguments (given 1, expected 0)
+
+    Time.new(2017, 9, 16, 17, 0).next_month    # => 2017-10-16 17:00:00 +0300
+    Time.new(2017, 9, 16, 17, 0).next_month(1)
+    # => ArgumentError: wrong number of arguments (given 1, expected 0)
+    ```
+
+    After:
+    ```
+    Time.new(2017, 9, 16, 17, 0).prev_month    # => 2017-08-16 17:00:00 +0300
+    Time.new(2017, 9, 16, 17, 0).prev_month(1) # => 2017-08-16 17:00:00 +0300
+
+    Time.new(2017, 9, 16, 17, 0).next_month    # => 2017-10-16 17:00:00 +0300
+    Time.new(2017, 9, 16, 17, 0).next_month(1) # => 2017-10-16 17:00:00 +0300
+    ```
+
+    *bogdanvlviv*
+
+*   Add same method signature for `Time#prev_day` and `Time#next_day`
+    in accordance with `Date#prev_day`, `Date#next_day`.
+
+    Allows pass argument for `Time#prev_day` and `Time#next_day`.
+
+    Before:
+    ```
+    Time.new(2017, 9, 16, 17, 0).prev_day    # => 2017-09-15 17:00:00 +0300
+    Time.new(2017, 9, 16, 17, 0).prev_day(1)
+    # => ArgumentError: wrong number of arguments (given 1, expected 0)
+
+    Time.new(2017, 9, 16, 17, 0).next_day    # => 2017-09-17 17:00:00 +0300
+    Time.new(2017, 9, 16, 17, 0).next_day(1)
+    # => ArgumentError: wrong number of arguments (given 1, expected 0)
+    ```
+
+    After:
+    ```
+    Time.new(2017, 9, 16, 17, 0).prev_day    # => 2017-09-15 17:00:00 +0300
+    Time.new(2017, 9, 16, 17, 0).prev_day(1) # => 2017-09-15 17:00:00 +0300
+
+    Time.new(2017, 9, 16, 17, 0).next_day    # => 2017-09-17 17:00:00 +0300
+    Time.new(2017, 9, 16, 17, 0).next_day(1) # => 2017-09-17 17:00:00 +0300
+    ```
+
+    *bogdanvlviv*
+
+*   `IO#to_json` now returns the `to_s` representation, rather than
+    attempting to convert to an array. This fixes a bug where `IO#to_json`
+    would raise an `IOError` when called on an unreadable object.
+
+    Fixes #26132.
+
+    *Paul Kuruvilla*
+
+*   Remove deprecated `halt_callback_chains_on_return_false` option.
+
+    *Rafael Mendonça França*
+
+*   Remove deprecated `:if` and `:unless` string filter for callbacks.
+
+    *Rafael Mendonça França*
+
+*   `Hash#slice` now falls back to Ruby 2.5+'s built-in definition if defined.
+
+    *Akira Matsuda*
+
+*   Deprecate `secrets.secret_token`.
+
+    The architecture for secrets had a big upgrade between Rails 3 and Rails 4,
+    when the default changed from using `secret_token` to `secret_key_base`.
+
+    `secret_token` has been soft deprecated in documentation for four years
+    but is still in place to support apps created before Rails 4.
+    Deprecation warnings have been added to help developers upgrade their
+    applications to `secret_key_base`.
+
+    *claudiob*, *Kasper Timm Hansen*
+
+*   Return an instance of `HashWithIndifferentAccess` from `HashWithIndifferentAccess#transform_keys`.
+
+    *Yuji Yaginuma*
+
+*   Add key rotation support to `MessageEncryptor` and `MessageVerifier`
+
+    This change introduces a `rotate` method to both the `MessageEncryptor` and
+    `MessageVerifier` classes. This method accepts the same arguments and
+    options as the given classes' constructor. The `encrypt_and_verify` method
+    for `MessageEncryptor` and the `verified` method for `MessageVerifier` also
+    accept an optional keyword argument `:on_rotation` block which is called
+    when a rotated instance is used to decrypt or verify the message.
+
+    *Michael J Coyne*
+
+*   Deprecate `Module#reachable?` method.
+
+    *bogdanvlviv*
+
+*   Add `config/credentials.yml.enc` to store production app secrets.
+
+    Allows saving any authentication credentials for third party services
+    directly in repo encrypted with `config/master.key` or `ENV["RAILS_MASTER_KEY"]`.
+
+    This will eventually replace `Rails.application.secrets` and the encrypted
+    secrets introduced in Rails 5.1.
+
+    *DHH*, *Kasper Timm Hansen*
+
+*   Add `ActiveSupport::EncryptedFile` and `ActiveSupport::EncryptedConfiguration`.
+
+    Allows for stashing encrypted files or configuration directly in repo by
+    encrypting it with a key.
+
+    Backs the new credentials setup above, but can also be used independently.
+
+    *DHH*, *Kasper Timm Hansen*
+
+*   `Module#delegate_missing_to` now raises `DelegationError` if target is nil,
+    similar to `Module#delegate`.
+
+    *Anton Khamets*
+
+*   Update `String#camelize` to provide feedback when wrong option is passed
+
+    `String#camelize` was returning nil without any feedback when an
+    invalid option was passed as a parameter.
+
+    Previously:
+
+        'one_two'.camelize(true)
+        # => nil
+
+    Now:
+
+        'one_two'.camelize(true)
+        # => ArgumentError: Invalid option, use either :upper or :lower.
+
+    *Ricardo Díaz*
+
+*   Fix modulo operations involving durations
+
+    Rails 5.1 introduced `ActiveSupport::Duration::Scalar` as a wrapper
+    around numeric values as a way of ensuring a duration was the outcome of
+    an expression. However, the implementation was missing support for modulo
+    operations. This support has now been added and should result in a duration
+    being returned from expressions involving modulo operations.
+
+    Prior to Rails 5.1:
+
+        5.minutes % 2.minutes
+        # => 60
+
+    Now:
+
+        5.minutes % 2.minutes
+        # => 1 minute
+
+    Fixes #29603 and #29743.
+
+    *Sayan Chakraborty*, *Andrew White*
+
+*   Fix division where a duration is the denominator
+
+    PR #29163 introduced a change in behavior when a duration was the denominator
+    in a calculation - this was incorrect as dividing by a duration should always
+    return a `Numeric`. The behavior of previous versions of Rails has been restored.
+
+    Fixes #29592.
+
+    *Andrew White*
+
+*   Add purpose and expiry support to `ActiveSupport::MessageVerifier` &
+   `ActiveSupport::MessageEncryptor`.
+
+    For instance, to ensure a message is only usable for one intended purpose:
+
+        token = @verifier.generate("x", purpose: :shipping)
+
+        @verifier.verified(token, purpose: :shipping) # => "x"
+        @verifier.verified(token)                     # => nil
+
+    Or make it expire after a set time:
+
+        @verifier.generate("x", expires_in: 1.month)
+        @verifier.generate("y", expires_at: Time.now.end_of_year)
+
+    Showcased with `ActiveSupport::MessageVerifier`, but works the same for
+    `ActiveSupport::MessageEncryptor`'s `encrypt_and_sign` and `decrypt_and_verify`.
+
+    Pull requests: #29599, #29854
+
+    *Assain Jaleel*
+
+*   Make the order of `Hash#reverse_merge!` consistent with `HashWithIndifferentAccess`.
+
+    *Erol Fornoles*
+
+*   Add `freeze_time` helper which freezes time to `Time.now` in tests.
+
+    *Prathamesh Sonpatki*
+
+*   Default `ActiveSupport::MessageEncryptor` to use AES 256 GCM encryption.
+
+    On for new Rails 5.2 apps. Upgrading apps can find the config as a new
+    framework default.
+
+    *Assain Jaleel*
+
+*   Cache: `write_multi`
+
+        Rails.cache.write_multi foo: 'bar', baz: 'qux'
+
+    Plus faster fetch_multi with stores that implement `write_multi_entries`.
+    Keys that aren't found may be written to the cache store in one shot
+    instead of separate writes.
+
+    The default implementation simply calls `write_entry` for each entry.
+    Stores may override if they're capable of one-shot bulk writes, like
+    Redis `MSET`.
 
     *Jeremy Daer*
 
-Please check [5-0-stable](https://github.com/rails/rails/blob/5-0-stable/activesupport/CHANGELOG.md) for previous changes.
+*   Add default option to module and class attribute accessors.
+
+        mattr_accessor :settings, default: {}
+
+    Works for `mattr_reader`, `mattr_writer`, `cattr_accessor`, `cattr_reader`,
+    and `cattr_writer` as well.
+
+    *Genadi Samokovarov*
+
+*   Add `Date#prev_occurring` and `Date#next_occurring` to return specified next/previous occurring day of week.
+
+    *Shota Iguchi*
+
+*   Add default option to `class_attribute`.
+
+    Before:
+
+        class_attribute :settings
+        self.settings = {}
+
+    Now:
+
+        class_attribute :settings, default: {}
+
+    *DHH*
+
+*   `#singularize` and `#pluralize` now respect uncountables for the specified locale.
+
+    *Eilis Hamilton*
+
+*   Add `ActiveSupport::CurrentAttributes` to provide a thread-isolated attributes singleton.
+    Primary use case is keeping all the per-request attributes easily available to the whole system.
+
+    *DHH*
+
+*   Fix implicit coercion calculations with scalars and durations
+
+    Previously, calculations where the scalar is first would be converted to a duration
+    of seconds, but this causes issues with dates being converted to times, e.g:
+
+        Time.zone = "Beijing"           # => Asia/Shanghai
+        date = Date.civil(2017, 5, 20)  # => Mon, 20 May 2017
+        2 * 1.day                       # => 172800 seconds
+        date + 2 * 1.day                # => Mon, 22 May 2017 00:00:00 CST +08:00
+
+    Now, the `ActiveSupport::Duration::Scalar` calculation methods will try to maintain
+    the part structure of the duration where possible, e.g:
+
+        Time.zone = "Beijing"           # => Asia/Shanghai
+        date = Date.civil(2017, 5, 20)  # => Mon, 20 May 2017
+        2 * 1.day                       # => 2 days
+        date + 2 * 1.day                # => Mon, 22 May 2017
+
+    Fixes #29160, #28970.
+
+    *Andrew White*
+
+*   Add support for versioned cache entries. This enables the cache stores to recycle cache keys, greatly saving
+    on storage in cases with frequent churn. Works together with the separation of `#cache_key` and `#cache_version`
+    in Active Record and its use in Action Pack's fragment caching.
+
+    *DHH*
+
+*   Pass gem name and deprecation horizon to deprecation notifications.
+
+    *Willem van Bergen*
+
+*   Add support for `:offset` and `:zone` to `ActiveSupport::TimeWithZone#change`
+
+    *Andrew White*
+
+*   Add support for `:offset` to `Time#change`
+
+    Fixes #28723.
+
+    *Andrew White*
+
+*   Add `fetch_values` for `HashWithIndifferentAccess`
+
+    The method was originally added to `Hash` in Ruby 2.3.0.
+
+    *Josh Pencheon*
+
+
+Please check [5-1-stable](https://github.com/rails/rails/blob/5-1-stable/activesupport/CHANGELOG.md) for previous changes.
diff --git a/activesupport/MIT-LICENSE b/activesupport/MIT-LICENSE
index 40235833ba..8f769c0767 100644
--- a/activesupport/MIT-LICENSE
+++ b/activesupport/MIT-LICENSE
@@ -1,4 +1,4 @@
-Copyright (c) 2005-2016 David Heinemeier Hansson
+Copyright (c) 2005-2018 David Heinemeier Hansson
 
 Permission is hereby granted, free of charge, to any person obtaining
 a copy of this software and associated documentation files (the
diff --git a/activesupport/README.rdoc b/activesupport/README.rdoc
index 14ce204303..c770324be8 100644
--- a/activesupport/README.rdoc
+++ b/activesupport/README.rdoc
@@ -21,7 +21,7 @@ Source code can be downloaded as part of the Rails project on GitHub:
 
 Active Support is released under the MIT license:
 
-* http://www.opensource.org/licenses/MIT
+* https://opensource.org/licenses/MIT
 
 
 == Support
@@ -30,7 +30,7 @@ API documentation is at:
 
 * http://api.rubyonrails.org
 
-Bug reports can be filed for the Ruby on Rails project here:
+Bug reports for the Ruby on Rails project can be filed here:
 
 * https://github.com/rails/rails/issues
 
diff --git a/activesupport/Rakefile b/activesupport/Rakefile
index 7b56e36abf..8672ab1542 100644
--- a/activesupport/Rakefile
+++ b/activesupport/Rakefile
@@ -1,12 +1,14 @@
-require 'rake/testtask'
+# frozen_string_literal: true
 
-task :default => :test
+require "rake/testtask"
+
+task default: :test
 
 task :package
 
 Rake::TestTask.new do |t|
-  t.libs << 'test'
-  t.pattern = 'test/**/*_test.rb'
+  t.libs << "test"
+  t.pattern = "test/**/*_test.rb"
   t.warning = true
   t.verbose = true
   t.ruby_opts = ["--dev"] if defined?(JRUBY_VERSION)
@@ -15,7 +17,7 @@ end
 namespace :test do
   task :isolated do
     Dir.glob("test/**/*_test.rb").all? do |file|
-      sh(Gem.ruby, '-w', '-Ilib:test', file)
-    end or raise "Failures"
+      sh(Gem.ruby, "-w", "-Ilib:test", file)
+    end || raise("Failures")
   end
 end
diff --git a/activesupport/activesupport.gemspec b/activesupport/activesupport.gemspec
index c6ca969844..db801d2da2 100644
--- a/activesupport/activesupport.gemspec
+++ b/activesupport/activesupport.gemspec
@@ -1,27 +1,34 @@
-version = File.read(File.expand_path('../../RAILS_VERSION', __FILE__)).strip
+# frozen_string_literal: true
+
+version = File.read(File.expand_path("../RAILS_VERSION", __dir__)).strip
 
 Gem::Specification.new do |s|
   s.platform    = Gem::Platform::RUBY
-  s.name        = 'activesupport'
+  s.name        = "activesupport"
   s.version     = version
-  s.summary     = 'A toolkit of support libraries and Ruby core extensions extracted from the Rails framework.'
-  s.description = 'A toolkit of support libraries and Ruby core extensions extracted from the Rails framework. Rich support for multibyte strings, internationalization, time zones, and testing.'
+  s.summary     = "A toolkit of support libraries and Ruby core extensions extracted from the Rails framework."
+  s.description = "A toolkit of support libraries and Ruby core extensions extracted from the Rails framework. Rich support for multibyte strings, internationalization, time zones, and testing."
+
+  s.required_ruby_version = ">= 2.2.2"
 
-  s.required_ruby_version = '>= 2.2.2'
+  s.license = "MIT"
 
-  s.license = 'MIT'
+  s.author   = "David Heinemeier Hansson"
+  s.email    = "david@loudthinking.com"
+  s.homepage = "http://rubyonrails.org"
 
-  s.author   = 'David Heinemeier Hansson'
-  s.email    = 'david@loudthinking.com'
-  s.homepage = 'http://rubyonrails.org'
+  s.files        = Dir["CHANGELOG.md", "MIT-LICENSE", "README.rdoc", "lib/**/*"]
+  s.require_path = "lib"
 
-  s.files        = Dir['CHANGELOG.md', 'MIT-LICENSE', 'README.rdoc', 'lib/**/*']
-  s.require_path = 'lib'
+  s.rdoc_options.concat ["--encoding",  "UTF-8"]
 
-  s.rdoc_options.concat ['--encoding',  'UTF-8']
+  s.metadata = {
+    "source_code_uri" => "https://github.com/rails/rails/tree/v#{version}/activesupport",
+    "changelog_uri"   => "https://github.com/rails/rails/blob/v#{version}/activesupport/CHANGELOG.md"
+  }
 
-  s.add_dependency 'i18n',       '~> 0.7'
-  s.add_dependency 'tzinfo',     '~> 1.1'
-  s.add_dependency 'minitest',   '~> 5.1'
-  s.add_dependency 'concurrent-ruby', '~> 1.0', '>= 1.0.2'
+  s.add_dependency "i18n",       "~> 0.7"
+  s.add_dependency "tzinfo",     "~> 1.1"
+  s.add_dependency "minitest",   "~> 5.1"
+  s.add_dependency "concurrent-ruby", "~> 1.0", ">= 1.0.2"
 end
diff --git a/activesupport/bin/generate_tables b/activesupport/bin/generate_tables
index 2193533588..18199b2171 100755
--- a/activesupport/bin/generate_tables
+++ b/activesupport/bin/generate_tables
@@ -1,18 +1,19 @@
 #!/usr/bin/env ruby
+# frozen_string_literal: true
 
 begin
-  $:.unshift(File.expand_path(File.dirname(__FILE__) + '/../lib'))
-  require 'active_support'
+  $:.unshift(File.expand_path("../lib", __dir__))
+  require "active_support"
 rescue IOError
 end
 
-require 'open-uri'
-require 'tmpdir'
+require "open-uri"
+require "tmpdir"
+require "fileutils"
 
 module ActiveSupport
   module Multibyte
     module Unicode
-
       class UnicodeDatabase
         def load; end
       end
@@ -20,10 +21,10 @@ module ActiveSupport
       class DatabaseGenerator
         BASE_URI = "http://www.unicode.org/Public/#{UNICODE_VERSION}/ucd/"
         SOURCES = {
-          :codepoints => BASE_URI + 'UnicodeData.txt',
-          :composition_exclusion => BASE_URI + 'CompositionExclusions.txt',
-          :grapheme_break_property => BASE_URI + 'auxiliary/GraphemeBreakProperty.txt',
-          :cp1252 => 'http://unicode.org/Public/MAPPINGS/VENDORS/MICSFT/WINDOWS/CP1252.TXT'
+          codepoints: BASE_URI + "UnicodeData.txt",
+          composition_exclusion: BASE_URI + "CompositionExclusions.txt",
+          grapheme_break_property: BASE_URI + "auxiliary/GraphemeBreakProperty.txt",
+          cp1252: "http://unicode.org/Public/MAPPINGS/VENDORS/MICSFT/WINDOWS/CP1252.TXT"
         }
 
         def initialize
@@ -52,9 +53,9 @@ module ActiveSupport
           codepoint.code              = $1.hex
           codepoint.combining_class   = Integer($4)
           codepoint.decomp_type       = $7
-          codepoint.decomp_mapping    = ($8=='') ? nil : $8.split.collect(&:hex)
-          codepoint.uppercase_mapping = ($16=='') ? 0 : $16.hex
-          codepoint.lowercase_mapping = ($17=='') ? 0 : $17.hex
+          codepoint.decomp_mapping    = ($8 == "") ? nil : $8.split.collect(&:hex)
+          codepoint.uppercase_mapping = ($16 == "") ? 0 : $16.hex
+          codepoint.lowercase_mapping = ($17 == "") ? 0 : $17.hex
           @ucd.codepoints[codepoint.code] = codepoint
         end
 
@@ -62,8 +63,8 @@ module ActiveSupport
           if line =~ /^([0-9A-F.]+)\s*;\s*([\w]+)\s*#/
             type = $2.downcase.intern
             @ucd.boundary[type] ||= []
-            if $1.include? '..'
-              parts = $1.split '..'
+            if $1.include? ".."
+              parts = $1.split ".."
               @ucd.boundary[type] << (parts[0].hex..parts[1].hex)
             else
               @ucd.boundary[type] << $1.hex
@@ -85,7 +86,7 @@ module ActiveSupport
 
         def create_composition_map
           @ucd.codepoints.each do |_, cp|
-            if !cp.nil? and cp.combining_class == 0 and cp.decomp_type.nil? and !cp.decomp_mapping.nil? and cp.decomp_mapping.length == 2 and @ucd.codepoints[cp.decomp_mapping[0]].combining_class == 0 and !@ucd.composition_exclusion.include?(cp.code)
+            if !cp.nil? && cp.combining_class == 0 && cp.decomp_type.nil? && !cp.decomp_mapping.nil? && cp.decomp_mapping.length == 2 && @ucd.codepoints[cp.decomp_mapping[0]].combining_class == 0 && !@ucd.composition_exclusion.include?(cp.code)
               @ucd.composition_map[cp.decomp_mapping[0]] ||= {}
               @ucd.composition_map[cp.decomp_mapping[0]][cp.decomp_mapping[1]] = cp.code
             end
@@ -93,7 +94,7 @@ module ActiveSupport
         end
 
         def normalize_boundary_map
-          @ucd.boundary.each do |k,v|
+          @ucd.boundary.each do |k, v|
             if [:lf, :cr].include? k
               @ucd.boundary[k] = v[0]
             end
@@ -102,10 +103,11 @@ module ActiveSupport
 
         def parse
           SOURCES.each do |type, url|
-            filename =  File.join(Dir.tmpdir, "#{url.split('/').last}")
+            filename = File.join(Dir.tmpdir, UNICODE_VERSION, "#{url.split('/').last}")
             unless File.exist?(filename)
               $stderr.puts "Downloading #{url.split('/').last}"
-              File.open(filename, 'wb') do |target|
+              FileUtils.mkdir_p(File.dirname(filename))
+              File.open(filename, "wb") do |target|
                 open(url) do |source|
                   source.each_line { |line| target.write line }
                 end
@@ -120,7 +122,7 @@ module ActiveSupport
         end
 
         def dump_to(filename)
-          File.open(filename, 'wb') do |f|
+          File.open(filename, "wb") do |f|
             f.write Marshal.dump([@ucd.codepoints, @ucd.composition_exclusion, @ucd.composition_map, @ucd.boundary, @ucd.cp1252])
           end
         end
diff --git a/activesupport/bin/test b/activesupport/bin/test
index 404cabba51..c53377cc97 100755
--- a/activesupport/bin/test
+++ b/activesupport/bin/test
@@ -1,4 +1,5 @@
 #!/usr/bin/env ruby
-COMPONENT_ROOT = File.expand_path("../../", __FILE__)
-require File.expand_path("../tools/test", COMPONENT_ROOT)
-exit Minitest.run(ARGV)
+# frozen_string_literal: true
+
+COMPONENT_ROOT = File.expand_path("..", __dir__)
+require_relative "../../tools/test"
diff --git a/activesupport/lib/active_support.rb b/activesupport/lib/active_support.rb
index 11569add37..a4fb697669 100644
--- a/activesupport/lib/active_support.rb
+++ b/activesupport/lib/active_support.rb
@@ -1,5 +1,7 @@
+# frozen_string_literal: true
+
 #--
-# Copyright (c) 2005-2016 David Heinemeier Hansson
+# Copyright (c) 2005-2018 David Heinemeier Hansson
 #
 # Permission is hereby granted, free of charge, to any person obtaining
 # a copy of this software and associated documentation files (the
@@ -21,7 +23,7 @@
 # WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 #++
 
-require 'securerandom'
+require "securerandom"
 require "active_support/dependencies/autoload"
 require "active_support/version"
 require "active_support/logger"
@@ -32,6 +34,7 @@ module ActiveSupport
   extend ActiveSupport::Autoload
 
   autoload :Concern
+  autoload :CurrentAttributes
   autoload :Dependencies
   autoload :DescendantsTracker
   autoload :ExecutionWrapper
@@ -50,6 +53,7 @@ module ActiveSupport
     autoload :Callbacks
     autoload :Configurable
     autoload :Deprecation
+    autoload :Digest
     autoload :Gzip
     autoload :Inflector
     autoload :JSON
@@ -79,14 +83,6 @@ module ActiveSupport
 
   cattr_accessor :test_order # :nodoc:
 
-  def self.halt_callback_chains_on_return_false
-    Callbacks.halt_and_display_warning_on_return_false
-  end
-
-  def self.halt_callback_chains_on_return_false=(value)
-    Callbacks.halt_and_display_warning_on_return_false = value
-  end
-
   def self.to_time_preserves_timezone
     DateAndTime::Compatibility.preserve_timezone
   end
diff --git a/activesupport/lib/active_support/all.rb b/activesupport/lib/active_support/all.rb
index f537818300..4adf446af8 100644
--- a/activesupport/lib/active_support/all.rb
+++ b/activesupport/lib/active_support/all.rb
@@ -1,3 +1,5 @@
-require 'active_support'
-require 'active_support/time'
-require 'active_support/core_ext'
+# frozen_string_literal: true
+
+require "active_support"
+require "active_support/time"
+require "active_support/core_ext"
diff --git a/activesupport/lib/active_support/array_inquirer.rb b/activesupport/lib/active_support/array_inquirer.rb
index ea328f603e..b2b9e9c0b7 100644
--- a/activesupport/lib/active_support/array_inquirer.rb
+++ b/activesupport/lib/active_support/array_inquirer.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActiveSupport
   # Wrapping an array in an +ArrayInquirer+ gives a friendlier way to check
   # its string-like contents:
@@ -20,7 +22,7 @@ module ActiveSupport
     #   variants.any?(:phone, :tablet)     # => true
     #   variants.any?('phone', 'desktop')  # => true
     #   variants.any?(:desktop, :watch)    # => false
-    def any?(*candidates, &block)
+    def any?(*candidates)
       if candidates.none?
         super
       else
@@ -32,11 +34,11 @@ module ActiveSupport
 
     private
       def respond_to_missing?(name, include_private = false)
-        name[-1] == '?'
+        (name[-1] == "?") || super
       end
 
       def method_missing(name, *args)
-        if name[-1] == '?'
+        if name[-1] == "?"
           any?(name[0..-2])
         else
           super
diff --git a/activesupport/lib/active_support/backtrace_cleaner.rb b/activesupport/lib/active_support/backtrace_cleaner.rb
index e161ec4cca..16dd733ddb 100644
--- a/activesupport/lib/active_support/backtrace_cleaner.rb
+++ b/activesupport/lib/active_support/backtrace_cleaner.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActiveSupport
   # Backtraces often include many lines that are not relevant for the context
   # under review. This makes it hard to find the signal amongst the backtrace
@@ -12,9 +14,9 @@ module ActiveSupport
   # is to exclude the output of a noisy library from the backtrace, so that you
   # can focus on the rest.
   #
-  #   bc = BacktraceCleaner.new
+  #   bc = ActiveSupport::BacktraceCleaner.new
   #   bc.add_filter   { |line| line.gsub(Rails.root.to_s, '') } # strip the Rails.root prefix
-  #   bc.add_silencer { |line| line =~ /mongrel|rubygems/ } # skip any lines from mongrel or rubygems
+  #   bc.add_silencer { |line| line =~ /puma|rubygems/ } # skip any lines from puma or rubygems
   #   bc.clean(exception.backtrace) # perform the cleanup
   #
   # To reconfigure an existing BacktraceCleaner (like the default one in Rails)
@@ -59,8 +61,8 @@ module ActiveSupport
     # Adds a silencer from the block provided. If the silencer returns +true+
     # for a given line, it will be excluded from the clean backtrace.
     #
-    #   # Will reject all lines that include the word "mongrel", like "/gems/mongrel/server.rb" or "/app/my_mongrel_server/rb"
-    #   backtrace_cleaner.add_silencer { |line| line =~ /mongrel/ }
+    #   # Will reject all lines that include the word "puma", like "/gems/puma/server.rb" or "/app/my_puma_server/rb"
+    #   backtrace_cleaner.add_silencer { |line| line =~ /puma/ }
     def add_silencer(&block)
       @silencers << block
     end
diff --git a/activesupport/lib/active_support/benchmarkable.rb b/activesupport/lib/active_support/benchmarkable.rb
index 3988b147ac..f481d68198 100644
--- a/activesupport/lib/active_support/benchmarkable.rb
+++ b/activesupport/lib/active_support/benchmarkable.rb
@@ -1,5 +1,7 @@
-require 'active_support/core_ext/benchmark'
-require 'active_support/core_ext/hash/keys'
+# frozen_string_literal: true
+
+require "active_support/core_ext/benchmark"
+require "active_support/core_ext/hash/keys"
 
 module ActiveSupport
   module Benchmarkable
@@ -39,7 +41,7 @@ module ActiveSupport
 
         result = nil
         ms = Benchmark.ms { result = options[:silence] ? logger.silence { yield } : yield }
-        logger.send(options[:level], '%s (%.1fms)' % [ message, ms ])
+        logger.send(options[:level], "%s (%.1fms)" % [ message, ms ])
         result
       else
         yield
diff --git a/activesupport/lib/active_support/builder.rb b/activesupport/lib/active_support/builder.rb
index 321e462acd..3fa7e6b26d 100644
--- a/activesupport/lib/active_support/builder.rb
+++ b/activesupport/lib/active_support/builder.rb
@@ -1,5 +1,7 @@
+# frozen_string_literal: true
+
 begin
-  require 'builder'
+  require "builder"
 rescue LoadError => e
   $stderr.puts "You don't have builder installed in your application. Please add it to your Gemfile and run bundle install"
   raise e
diff --git a/activesupport/lib/active_support/cache.rb b/activesupport/lib/active_support/cache.rb
index 179ca13b49..8301b8c7cb 100644
--- a/activesupport/lib/active_support/cache.rb
+++ b/activesupport/lib/active_support/cache.rb
@@ -1,29 +1,29 @@
-require 'benchmark'
-require 'zlib'
-require 'active_support/core_ext/array/extract_options'
-require 'active_support/core_ext/array/wrap'
-require 'active_support/core_ext/benchmark'
-require 'active_support/core_ext/module/attribute_accessors'
-require 'active_support/core_ext/numeric/bytes'
-require 'active_support/core_ext/numeric/time'
-require 'active_support/core_ext/object/to_param'
-require 'active_support/core_ext/string/inflections'
-require 'active_support/core_ext/string/strip'
+# frozen_string_literal: true
+
+require "zlib"
+require "active_support/core_ext/array/extract_options"
+require "active_support/core_ext/array/wrap"
+require "active_support/core_ext/module/attribute_accessors"
+require "active_support/core_ext/numeric/bytes"
+require "active_support/core_ext/numeric/time"
+require "active_support/core_ext/object/to_param"
+require "active_support/core_ext/string/inflections"
 
 module ActiveSupport
   # See ActiveSupport::Cache::Store for documentation.
   module Cache
-    autoload :FileStore,     'active_support/cache/file_store'
-    autoload :MemoryStore,   'active_support/cache/memory_store'
-    autoload :MemCacheStore, 'active_support/cache/mem_cache_store'
-    autoload :NullStore,     'active_support/cache/null_store'
+    autoload :FileStore,        "active_support/cache/file_store"
+    autoload :MemoryStore,      "active_support/cache/memory_store"
+    autoload :MemCacheStore,    "active_support/cache/mem_cache_store"
+    autoload :NullStore,        "active_support/cache/null_store"
+    autoload :RedisCacheStore,  "active_support/cache/redis_cache_store"
 
     # These options mean something to all cache implementations. Individual cache
     # implementations may support additional options.
     UNIVERSAL_OPTIONS = [:namespace, :compress, :compress_threshold, :expires_in, :race_condition_ttl]
 
     module Strategy
-      autoload :LocalCache, 'active_support/cache/strategy/local_cache'
+      autoload :LocalCache, "active_support/cache/strategy/local_cache"
     end
 
     class << self
@@ -73,12 +73,12 @@ module ActiveSupport
       # each of elements in the array will be turned into parameters/keys and
       # concatenated into a single key. For example:
       #
-      #   expand_cache_key([:foo, :bar])               # => "foo/bar"
-      #   expand_cache_key([:foo, :bar], "namespace")  # => "namespace/foo/bar"
+      #   ActiveSupport::Cache.expand_cache_key([:foo, :bar])               # => "foo/bar"
+      #   ActiveSupport::Cache.expand_cache_key([:foo, :bar], "namespace")  # => "namespace/foo/bar"
       #
       # The +key+ argument can also respond to +cache_key+ or +to_param+.
       def expand_cache_key(key, namespace = nil)
-        expanded_cache_key = namespace ? "#{namespace}/" : ""
+        expanded_cache_key = (namespace ? "#{namespace}/" : "").dup
 
         if prefix = ENV["RAILS_CACHE_ID"] || ENV["RAILS_APP_VERSION"]
           expanded_cache_key << "#{prefix}/"
@@ -91,16 +91,19 @@ module ActiveSupport
       private
         def retrieve_cache_key(key)
           case
-          when key.respond_to?(:cache_key) then key.cache_key
-          when key.is_a?(Array)            then key.map { |element| retrieve_cache_key(element) }.to_param
-          when key.respond_to?(:to_a)      then retrieve_cache_key(key.to_a)
-          else                                  key.to_param
+          when key.respond_to?(:cache_key_with_version) then key.cache_key_with_version
+          when key.respond_to?(:cache_key)              then key.cache_key
+          when key.is_a?(Array)                         then key.map { |element| retrieve_cache_key(element) }.to_param
+          when key.respond_to?(:to_a)                   then retrieve_cache_key(key.to_a)
+          else                                               key.to_param
           end.to_s
         end
 
         # Obtains the specified cache store class, given the name of the +store+.
         # Raises an error when the store class cannot be found.
         def retrieve_store_class(store)
+          # require_relative cannot be used here because the class might be
+          # provided by another gem, like redis-activesupport for example.
           require "active_support/cache/#{store}"
         rescue LoadError => e
           raise "Could not find cache store adapter for #{store} (#{e})"
@@ -146,14 +149,13 @@ module ActiveSupport
     #   cache.namespace = -> { @last_mod_time }  # Set the namespace to a variable
     #   @last_mod_time = Time.now  # Invalidate the entire cache by changing namespace
     #
-    # Caches can also store values in a compressed format to save space and
-    # reduce time spent sending data. Since there is overhead, values must be
-    # large enough to warrant compression. To turn on compression either pass
-    # <tt>compress: true</tt> in the initializer or as an option to +fetch+
-    # or +write+. To specify the threshold at which to compress values, set the
-    # <tt>:compress_threshold</tt> option. The default threshold is 16K.
+    # Cached data larger than 1kB are compressed by default. To turn off
+    # compression, pass <tt>compress: false</tt> to the initializer or to
+    # individual +fetch+ or +write+ method calls. The 1kB compression
+    # threshold is configurable with the <tt>:compress_threshold</tt> option,
+    # specified in bytes.
     class Store
-      cattr_accessor :logger, :instance_writer => true
+      cattr_accessor :logger, instance_writer: true
 
       attr_reader :silence, :options
       alias :silence? :silence
@@ -200,18 +202,17 @@ module ActiveSupport
       # You may also specify additional options via the +options+ argument.
       # Setting <tt>force: true</tt> forces a cache "miss," meaning we treat
       # the cache value as missing even if it's present. Passing a block is
-      # required when `force` is true so this always results in a cache write.
+      # required when +force+ is true so this always results in a cache write.
       #
       #   cache.write('today', 'Monday')
       #   cache.fetch('today', force: true) { 'Tuesday' } # => 'Tuesday'
       #   cache.fetch('today', force: true) # => ArgumentError
       #
-      # The `:force` option is useful when you're calling some other method to
+      # The +:force+ option is useful when you're calling some other method to
       # ask whether you should force a cache write. Otherwise, it's clearer to
-      # just call `Cache#write`.
+      # just call <tt>Cache#write</tt>.
       #
-      # Setting <tt>:compress</tt> will store a large cache entry set by the call
-      # in a compressed format.
+      # Setting <tt>compress: false</tt> disables compression of the cache entry.
       #
       # Setting <tt>:expires_in</tt> will set an expiration time on the cache.
       # All caches support auto-expiring content after a specified number of
@@ -222,6 +223,10 @@ module ActiveSupport
       #   cache = ActiveSupport::Cache::MemoryStore.new(expires_in: 5.minutes)
       #   cache.write(key, value, expires_in: 1.minute) # Set a lower value for one entry
       #
+      # Setting <tt>:version</tt> verifies the cache stored under <tt>name</tt>
+      # is of the same version. nil is returned on mismatches despite contents.
+      # This feature is used to support recyclable cache keys.
+      #
       # Setting <tt>:race_condition_ttl</tt> is very useful in situations where
       # a cache entry is used very frequently and is under heavy load. If a
       # cache expires and due to heavy load several different processes will try
@@ -290,6 +295,7 @@ module ActiveSupport
           instrument(:read, name, options) do |payload|
             cached_entry = read_entry(key, options) unless options[:force]
             entry = handle_expired_entry(cached_entry, key, options)
+            entry = nil if entry && entry.mismatched?(normalize_version(name, options))
             payload[:super_operation] = :fetch if payload
             payload[:hit] = !!entry if payload
           end
@@ -300,27 +306,36 @@ module ActiveSupport
             save_block_result_to_cache(name, options) { |_name| yield _name }
           end
         elsif options && options[:force]
-          raise ArgumentError, 'Missing block: Calling `Cache#fetch` with `force: true` requires a block.'
+          raise ArgumentError, "Missing block: Calling `Cache#fetch` with `force: true` requires a block."
         else
           read(name, options)
         end
       end
 
-      # Fetches data from the cache, using the given key. If there is data in
+      # Reads data from the cache, using the given key. If there is data in
       # the cache with the given key, then that data is returned. Otherwise,
       # +nil+ is returned.
       #
+      # Note, if data was written with the <tt>:expires_in<tt> or <tt>:version</tt> options,
+      # both of these conditions are applied before the data is returned.
+      #
       # Options are passed to the underlying cache implementation.
       def read(name, options = nil)
         options = merged_options(options)
-        key = normalize_key(name, options)
+        key     = normalize_key(name, options)
+        version = normalize_version(name, options)
+
         instrument(:read, name, options) do |payload|
           entry = read_entry(key, options)
+
           if entry
             if entry.expired?
               delete_entry(key, options)
               payload[:hit] = false if payload
               nil
+            elsif entry.mismatched?(version)
+              payload[:hit] = false if payload
+              nil
             else
               payload[:hit] = true if payload
               entry.value
@@ -344,11 +359,15 @@ module ActiveSupport
 
         results = {}
         names.each do |name|
-          key = normalize_key(name, options)
-          entry = read_entry(key, options)
+          key     = normalize_key(name, options)
+          version = normalize_version(name, options)
+          entry   = read_entry(key, options)
+
           if entry
             if entry.expired?
               delete_entry(key, options)
+            elsif entry.mismatched?(version)
+              # Skip mismatched versions
             else
               results[name] = entry.value
             end
@@ -357,10 +376,26 @@ module ActiveSupport
         results
       end
 
+      # Cache Storage API to write multiple values at once.
+      def write_multi(hash, options = nil)
+        options = merged_options(options)
+
+        instrument :write_multi, hash, options do |payload|
+          entries = hash.each_with_object({}) do |(name, value), memo|
+            memo[normalize_key(name, options)] = Entry.new(value, options.merge(version: normalize_version(name, options)))
+          end
+
+          write_multi_entries entries, options
+        end
+      end
+
       # Fetches data from the cache, using the given keys. If there is data in
       # the cache with the given keys, then that data is returned. Otherwise,
       # the supplied block is called for each key for which there was no data,
       # and the result will be written to the cache and returned.
+      # Therefore, you need to pass a block that returns the data to be written
+      # to the cache. If you do not want to write the cache when the cache is
+      # not found, use #read_multi.
       #
       # Options are passed to the underlying cache implementation.
       #
@@ -374,16 +409,19 @@ module ActiveSupport
       #   #      "unknown_key" => "Fallback value for key: unknown_key" }
       #
       def fetch_multi(*names)
+        raise ArgumentError, "Missing block: `Cache#fetch_multi` requires a block." unless block_given?
+
         options = names.extract_options!
         options = merged_options(options)
-        results = read_multi(*names, options)
 
-        names.each_with_object({}) do |name, memo|
-          memo[name] = results.fetch(name) do
-            value = yield name
-            write(name, value, options)
-            value
+        read_multi(*names, options).tap do |results|
+          writes = {}
+
+          (names - results.keys).each do |name|
+            results[name] = writes[name] = yield(name)
           end
+
+          write_multi writes, options
         end
       end
 
@@ -394,7 +432,7 @@ module ActiveSupport
         options = merged_options(options)
 
         instrument(:write, name, options) do
-          entry = Entry.new(value, options)
+          entry = Entry.new(value, options.merge(version: normalize_version(name, options)))
           write_entry(normalize_key(name, options), entry, options)
         end
       end
@@ -418,7 +456,7 @@ module ActiveSupport
 
         instrument(:exist?, name) do
           entry = read_entry(normalize_key(name, options), options)
-          (entry && !entry.expired?) || false
+          (entry && !entry.expired? && !entry.mismatched?(normalize_version(name, options))) || false
         end
       end
 
@@ -468,16 +506,16 @@ module ActiveSupport
         raise NotImplementedError.new("#{self.class.name} does not support clear")
       end
 
-      protected
+      private
         # Adds the namespace defined in the options to a pattern designed to
         # match keys. Implementations that support delete_matched should call
         # this method to translate a pattern that matches names into one that
         # matches namespaced keys.
-        def key_matcher(pattern, options)
+        def key_matcher(pattern, options) # :doc:
           prefix = options[:namespace].is_a?(Proc) ? options[:namespace].call : options[:namespace]
           if prefix
             source = pattern.source
-            if source.start_with?('^')
+            if source.start_with?("^")
               source = source[1, source.length]
             else
               source = ".*#{source[0, source.length]}"
@@ -490,25 +528,32 @@ module ActiveSupport
 
         # Reads an entry from the cache implementation. Subclasses must implement
         # this method.
-        def read_entry(key, options) # :nodoc:
+        def read_entry(key, options)
           raise NotImplementedError.new
         end
 
         # Writes an entry to the cache implementation. Subclasses must implement
         # this method.
-        def write_entry(key, entry, options) # :nodoc:
+        def write_entry(key, entry, options)
           raise NotImplementedError.new
         end
 
+        # Writes multiple entries to the cache implementation. Subclasses MAY
+        # implement this method.
+        def write_multi_entries(hash, options)
+          hash.each do |key, entry|
+            write_entry key, entry, options
+          end
+        end
+
         # Deletes an entry from the cache implementation. Subclasses must
         # implement this method.
-        def delete_entry(key, options) # :nodoc:
+        def delete_entry(key, options)
           raise NotImplementedError.new
         end
 
-      private
         # Merges the default options with ones specific to a method call.
-        def merged_options(call_options) # :nodoc:
+        def merged_options(call_options)
           if call_options
             options.merge(call_options)
           else
@@ -516,50 +561,74 @@ module ActiveSupport
           end
         end
 
+        # Expands and namespaces the cache key. May be overridden by
+        # cache stores to do additional normalization.
+        def normalize_key(key, options = nil)
+          namespace_key expanded_key(key), options
+        end
+
+        # Prefix the key with a namespace string:
+        #
+        #   namespace_key 'foo', namespace: 'cache'
+        #   # => 'cache:foo'
+        #
+        # With a namespace block:
+        #
+        #   namespace_key 'foo', namespace: -> { 'cache' }
+        #   # => 'cache:foo'
+        def namespace_key(key, options = nil)
+          options = merged_options(options)
+          namespace = options[:namespace]
+
+          if namespace.respond_to?(:call)
+            namespace = namespace.call
+          end
+
+          if namespace
+            "#{namespace}:#{key}"
+          else
+            key
+          end
+        end
+
         # Expands key to be a consistent string value. Invokes +cache_key+ if
         # object responds to +cache_key+. Otherwise, +to_param+ method will be
         # called. If the key is a Hash, then keys will be sorted alphabetically.
-        def expanded_key(key) # :nodoc:
+        def expanded_key(key)
           return key.cache_key.to_s if key.respond_to?(:cache_key)
 
           case key
           when Array
             if key.size > 1
-              key = key.collect{|element| expanded_key(element)}
+              key = key.collect { |element| expanded_key(element) }
             else
               key = key.first
             end
           when Hash
-            key = key.sort_by { |k,_| k.to_s }.collect{|k,v| "#{k}=#{v}"}
+            key = key.sort_by { |k, _| k.to_s }.collect { |k, v| "#{k}=#{v}" }
           end
 
           key.to_param
         end
 
-        # Prefixes a key with the namespace. Namespace and key will be delimited
-        # with a colon.
-        def normalize_key(key, options)
-          key = expanded_key(key)
-          namespace = options[:namespace] if options
-          prefix = namespace.is_a?(Proc) ? namespace.call : namespace
-          key = "#{prefix}:#{key}" if prefix
-          key
+        def normalize_version(key, options = nil)
+          (options && options[:version].try(:to_param)) || expanded_version(key)
         end
 
-        def namespaced_key(*args)
-          ActiveSupport::Deprecation.warn(<<-MESSAGE.strip_heredoc)
-            `namespaced_key` is deprecated and will be removed from Rails 5.1.
-            Please use `normalize_key` which will return a fully resolved key.
-          MESSAGE
-          normalize_key(*args)
+        def expanded_version(key)
+          case
+          when key.respond_to?(:cache_version) then key.cache_version.to_param
+          when key.is_a?(Array)                then key.map { |element| expanded_version(element) }.compact.to_param
+          when key.respond_to?(:to_a)          then expanded_version(key.to_a)
+          end
         end
 
         def instrument(operation, key, options = nil)
           log { "Cache #{operation}: #{normalize_key(key, options)}#{options.blank? ? "" : " (#{options.inspect})"}" }
 
-          payload = { :key => key }
+          payload = { key: key }
           payload.merge!(options) if options.is_a?(Hash)
-          ActiveSupport::Notifications.instrument("cache_#{operation}.active_support", payload){ yield(payload) }
+          ActiveSupport::Notifications.instrument("cache_#{operation}.active_support", payload) { yield(payload) }
         end
 
         def log
@@ -574,7 +643,7 @@ module ActiveSupport
               # When an entry has a positive :race_condition_ttl defined, put the stale entry back into the cache
               # for a brief period while the entry is being recalculated.
               entry.expires_at = Time.now + race_ttl
-              write_entry(key, entry, :expires_in => race_ttl * 2)
+              write_entry(key, entry, expires_in: race_ttl * 2)
             else
               delete_entry(key, options)
             end
@@ -584,7 +653,7 @@ module ActiveSupport
         end
 
         def get_entry_value(entry, name, options)
-          instrument(:fetch_hit, name, options) { }
+          instrument(:fetch_hit, name, options) {}
           entry.value
         end
 
@@ -598,14 +667,17 @@ module ActiveSupport
         end
     end
 
-    # This class is used to represent cache entries. Cache entries have a value and an optional
-    # expiration time. The expiration time is used to support the :race_condition_ttl option
-    # on the cache.
+    # This class is used to represent cache entries. Cache entries have a value, an optional
+    # expiration time, and an optional version. The expiration time is used to support the :race_condition_ttl option
+    # on the cache. The version is used to support the :version option on the cache for rejecting
+    # mismatches.
     #
     # Since cache entries in most instances will be serialized, the internals of this class are highly optimized
     # using short instance variable names that are lazily defined.
     class Entry # :nodoc:
-      DEFAULT_COMPRESS_LIMIT = 16.kilobytes
+      attr_reader :version
+
+      DEFAULT_COMPRESS_LIMIT = 1.kilobyte
 
       # Creates a new cache entry for the specified value. Options supported are
       # +:compress+, +:compress_threshold+, and +:expires_in+.
@@ -617,6 +689,7 @@ module ActiveSupport
           @value = value
         end
 
+        @version    = options[:version]
         @created_at = Time.now.to_f
         @expires_in = options[:expires_in]
         @expires_in = @expires_in.to_f if @expires_in
@@ -626,6 +699,10 @@ module ActiveSupport
         compressed? ? uncompress(@value) : @value
       end
 
+      def mismatched?(version)
+        @version && version && @version != version
+      end
+
       # Checks if the entry is expired. The +expires_in+ parameter can override
       # the value set when the entry was created.
       def expired?
@@ -675,8 +752,8 @@ module ActiveSupport
 
       private
         def should_compress?(value, options)
-          if value && options[:compress]
-            compress_threshold = options[:compress_threshold] || DEFAULT_COMPRESS_LIMIT
+          if value && options.fetch(:compress, true)
+            compress_threshold = options.fetch(:compress_threshold, DEFAULT_COMPRESS_LIMIT)
             serialized_value_size = (value.is_a?(String) ? value : Marshal.dump(value)).bytesize
 
             return true if serialized_value_size >= compress_threshold
diff --git a/activesupport/lib/active_support/cache/file_store.rb b/activesupport/lib/active_support/cache/file_store.rb
index 99c55b1aa4..a0f44aac0f 100644
--- a/activesupport/lib/active_support/cache/file_store.rb
+++ b/activesupport/lib/active_support/cache/file_store.rb
@@ -1,7 +1,9 @@
-require 'active_support/core_ext/marshal'
-require 'active_support/core_ext/file/atomic'
-require 'active_support/core_ext/string/conversions'
-require 'uri/common'
+# frozen_string_literal: true
+
+require "active_support/core_ext/marshal"
+require "active_support/core_ext/file/atomic"
+require "active_support/core_ext/string/conversions"
+require "uri/common"
 
 module ActiveSupport
   module Cache
@@ -16,8 +18,8 @@ module ActiveSupport
       DIR_FORMATTER = "%03X"
       FILENAME_MAX_SIZE = 228 # max filename size on file system is 255, minus room for timestamp and random characters appended by Tempfile (used by atomic write)
       FILEPATH_MAX_SIZE = 900 # max is 1024, plus some room
-      EXCLUDED_DIRS = ['.', '..'].freeze
-      GITKEEP_FILES = ['.gitkeep', '.keep'].freeze
+      EXCLUDED_DIRS = [".", ".."].freeze
+      GITKEEP_FILES = [".gitkeep", ".keep"].freeze
 
       def initialize(cache_path, options = nil)
         super(options)
@@ -29,7 +31,7 @@ module ActiveSupport
       # config file when using +FileStore+ because everything in that directory will be deleted.
       def clear(options = nil)
         root_dirs = exclude_from(cache_path, EXCLUDED_DIRS + GITKEEP_FILES)
-        FileUtils.rm_r(root_dirs.collect{|f| File.join(cache_path, f)})
+        FileUtils.rm_r(root_dirs.collect { |f| File.join(cache_path, f) })
       rescue Errno::ENOENT
       end
 
@@ -37,9 +39,8 @@ module ActiveSupport
       def cleanup(options = nil)
         options = merged_options(options)
         search_dir(cache_path) do |fname|
-          key = file_path_key(fname)
-          entry = read_entry(key, options)
-          delete_entry(key, options) if entry && entry.expired?
+          entry = read_entry(fname, options)
+          delete_entry(fname, options) if entry && entry.expired?
         end
       end
 
@@ -66,7 +67,7 @@ module ActiveSupport
         end
       end
 
-      protected
+      private
 
         def read_entry(key, options)
           if File.exist?(key)
@@ -80,7 +81,7 @@ module ActiveSupport
         def write_entry(key, entry, options)
           return false if options[:unless_exist] && File.exist?(key)
           ensure_cache_path(File.dirname(key))
-          File.atomic_write(key, cache_path) {|f| Marshal.dump(entry, f)}
+          File.atomic_write(key, cache_path) { |f| Marshal.dump(entry, f) }
           true
         end
 
@@ -98,11 +99,10 @@ module ActiveSupport
           end
         end
 
-      private
         # Lock a file for a block so only one process can modify it at a time.
-        def lock_file(file_name, &block) # :nodoc:
+        def lock_file(file_name, &block)
           if File.exist?(file_name)
-            File.open(file_name, 'r+') do |f|
+            File.open(file_name, "r+") do |f|
               begin
                 f.flock File::LOCK_EX
                 yield
@@ -121,7 +121,7 @@ module ActiveSupport
           fname = URI.encode_www_form_component(key)
 
           if fname.size > FILEPATH_MAX_SIZE
-            fname = Digest::MD5.hexdigest(key)
+            fname = ActiveSupport::Digest.hexdigest(key)
           end
 
           hash = Zlib.adler32(fname)
@@ -138,14 +138,6 @@ module ActiveSupport
           File.join(cache_path, DIR_FORMATTER % dir_1, DIR_FORMATTER % dir_2, *fname_paths)
         end
 
-        def key_file_path(key)
-          ActiveSupport::Deprecation.warn(<<-MESSAGE.strip_heredoc)
-            `key_file_path` is deprecated and will be removed from Rails 5.1.
-            Please use `normalize_key` which will return a fully resolved key or nothing.
-          MESSAGE
-          key
-        end
-
         # Translate a file path into a key.
         def file_path_key(path)
           fname = path[cache_path.to_s.size..-1].split(File::SEPARATOR, 4).last
diff --git a/activesupport/lib/active_support/cache/mem_cache_store.rb b/activesupport/lib/active_support/cache/mem_cache_store.rb
index 2ca4b51efa..df8bc8e43e 100644
--- a/activesupport/lib/active_support/cache/mem_cache_store.rb
+++ b/activesupport/lib/active_support/cache/mem_cache_store.rb
@@ -1,18 +1,19 @@
+# frozen_string_literal: true
+
 begin
-  require 'dalli'
+  require "dalli"
 rescue LoadError => e
   $stderr.puts "You don't have dalli installed in your application. Please add it to your Gemfile and run bundle install"
   raise e
 end
 
-require 'digest/md5'
-require 'active_support/core_ext/marshal'
-require 'active_support/core_ext/array/extract_options'
+require "active_support/core_ext/marshal"
+require "active_support/core_ext/array/extract_options"
 
 module ActiveSupport
   module Cache
     # A cache store implementation which stores data in Memcached:
-    # http://memcached.org/
+    # https://memcached.org
     #
     # This is currently the most popular cache store for production websites.
     #
@@ -26,24 +27,24 @@ module ActiveSupport
     class MemCacheStore < Store
       # Provide support for raw values in the local cache strategy.
       module LocalCacheWithRaw # :nodoc:
-        protected
-        def read_entry(key, options)
-          entry = super
-          if options[:raw] && local_cache && entry
-            entry = deserialize_entry(entry.value)
+        private
+          def read_entry(key, options)
+            entry = super
+            if options[:raw] && local_cache && entry
+              entry = deserialize_entry(entry.value)
+            end
+            entry
           end
-          entry
-        end
 
-        def write_entry(key, entry, options) # :nodoc:
-          if options[:raw] && local_cache
-            raw_entry = Entry.new(entry.value.to_s)
-            raw_entry.expires_at = entry.expires_at
-            super(key, raw_entry, options)
-          else
-            super
+          def write_entry(key, entry, options)
+            if options[:raw] && local_cache
+              raw_entry = Entry.new(entry.value.to_s)
+              raw_entry.expires_at = entry.expires_at
+              super(key, raw_entry, options)
+            else
+              super
+            end
           end
-        end
       end
 
       prepend Strategy::LocalCache
@@ -85,7 +86,7 @@ module ActiveSupport
           @data = addresses.first
         else
           mem_cache_options = options.dup
-          UNIVERSAL_OPTIONS.each{|name| mem_cache_options.delete(name)}
+          UNIVERSAL_OPTIONS.each { |name| mem_cache_options.delete(name) }
           @data = self.class.build_mem_cache(*(addresses + [mem_cache_options]))
         end
       end
@@ -96,13 +97,19 @@ module ActiveSupport
         options = names.extract_options!
         options = merged_options(options)
 
-        keys_to_names = Hash[names.map{|name| [normalize_key(name, options), name]}]
-        raw_values = @data.get_multi(keys_to_names.keys, :raw => true)
+        keys_to_names = Hash[names.map { |name| [normalize_key(name, options), name] }]
+
+        raw_values = @data.get_multi(keys_to_names.keys)
         values = {}
+
         raw_values.each do |key, value|
           entry = deserialize_entry(value)
-          values[keys_to_names[key]] = entry.value unless entry.expired?
+
+          unless entry.expired? || entry.mismatched?(normalize_version(keys_to_names[key], options))
+            values[keys_to_names[key]] = entry.value
+          end
         end
+
         values
       end
 
@@ -110,11 +117,11 @@ module ActiveSupport
       # operator and can only be used on values written with the :raw option.
       # Calling it on a value not stored with :raw will initialize that value
       # to zero.
-      def increment(name, amount = 1, options = nil) # :nodoc:
+      def increment(name, amount = 1, options = nil)
         options = merged_options(options)
-        instrument(:increment, name, :amount => amount) do
+        instrument(:increment, name, amount: amount) do
           rescue_error_with nil do
-            @data.incr(normalize_key(name, options), amount)
+            @data.incr(normalize_key(name, options), amount, options[:expires_in])
           end
         end
       end
@@ -123,11 +130,11 @@ module ActiveSupport
       # operator and can only be used on values written with the :raw option.
       # Calling it on a value not stored with :raw will initialize that value
       # to zero.
-      def decrement(name, amount = 1, options = nil) # :nodoc:
+      def decrement(name, amount = 1, options = nil)
         options = merged_options(options)
-        instrument(:decrement, name, :amount => amount) do
+        instrument(:decrement, name, amount: amount) do
           rescue_error_with nil do
-            @data.decr(normalize_key(name, options), amount)
+            @data.decr(normalize_key(name, options), amount, options[:expires_in])
           end
         end
       end
@@ -143,14 +150,14 @@ module ActiveSupport
         @data.stats
       end
 
-      protected
+      private
         # Read an entry from the cache.
-        def read_entry(key, options) # :nodoc:
+        def read_entry(key, options)
           rescue_error_with(nil) { deserialize_entry(@data.get(key, options)) }
         end
 
         # Write an entry to the cache.
-        def write_entry(key, entry, options) # :nodoc:
+        def write_entry(key, entry, options)
           method = options && options[:unless_exist] ? :add : :set
           value = options[:raw] ? entry.value.to_s : entry
           expires_in = options[:expires_in].to_i
@@ -164,28 +171,18 @@ module ActiveSupport
         end
 
         # Delete an entry from the cache.
-        def delete_entry(key, options) # :nodoc:
+        def delete_entry(key, options)
           rescue_error_with(false) { @data.delete(key) }
         end
 
-      private
-
         # Memcache keys are binaries. So we need to force their encoding to binary
         # before applying the regular expression to ensure we are escaping all
         # characters properly.
         def normalize_key(key, options)
           key = super.dup
           key = key.force_encoding(Encoding::ASCII_8BIT)
-          key = key.gsub(ESCAPE_KEY_CHARS){ |match| "%#{match.getbyte(0).to_s(16).upcase}" }
-          key = "#{key[0, 213]}:md5:#{Digest::MD5.hexdigest(key)}" if key.size > 250
-          key
-        end
-
-        def escape_key(key)
-          ActiveSupport::Deprecation.warn(<<-MESSAGE.strip_heredoc)
-            `escape_key` is deprecated and will be removed from Rails 5.1.
-            Please use `normalize_key` which will return a fully resolved key or nothing.
-          MESSAGE
+          key = key.gsub(ESCAPE_KEY_CHARS) { |match| "%#{match.getbyte(0).to_s(16).upcase}" }
+          key = "#{key[0, 213]}:md5:#{ActiveSupport::Digest.hexdigest(key)}" if key.size > 250
           key
         end
 
diff --git a/activesupport/lib/active_support/cache/memory_store.rb b/activesupport/lib/active_support/cache/memory_store.rb
index 896c28ad8b..564ac17241 100644
--- a/activesupport/lib/active_support/cache/memory_store.rb
+++ b/activesupport/lib/active_support/cache/memory_store.rb
@@ -1,10 +1,12 @@
-require 'monitor'
+# frozen_string_literal: true
+
+require "monitor"
 
 module ActiveSupport
   module Cache
     # A cache store implementation which stores everything into memory in the
     # same process. If you're running multiple Ruby on Rails server processes
-    # (which is the case if you're using mongrel_cluster or Phusion Passenger),
+    # (which is the case if you're using Phusion Passenger or puma clustered mode),
     # then this means that Rails server process instances won't be able
     # to share cache data with each other and this may not be the most
     # appropriate cache in that scenario.
@@ -28,6 +30,7 @@ module ActiveSupport
         @pruning = false
       end
 
+      # Delete all data stored in a given cache store.
       def clear(options = nil)
         synchronize do
           @data.clear
@@ -39,8 +42,8 @@ module ActiveSupport
       # Preemptively iterates through all stored keys and removes the ones which have expired.
       def cleanup(options = nil)
         options = merged_options(options)
-        instrument(:cleanup, :size => @data.size) do
-          keys = synchronize{ @data.keys }
+        instrument(:cleanup, size: @data.size) do
+          keys = synchronize { @data.keys }
           keys.each do |key|
             entry = @data[key]
             delete_entry(key, options) if entry && entry.expired?
@@ -56,8 +59,8 @@ module ActiveSupport
         begin
           start_time = Time.now
           cleanup
-          instrument(:prune, target_size, :from => @cache_size) do
-            keys = synchronize{ @key_access.keys.sort{|a,b| @key_access[a].to_f <=> @key_access[b].to_f} }
+          instrument(:prune, target_size, from: @cache_size) do
+            keys = synchronize { @key_access.keys.sort { |a, b| @key_access[a].to_f <=> @key_access[b].to_f } }
             keys.each do |key|
               delete_entry(key, options)
               return if @cache_size <= target_size || (max_time && Time.now - start_time > max_time)
@@ -83,6 +86,7 @@ module ActiveSupport
         modify_value(name, -amount, options)
       end
 
+      # Deletes cache entries if the cache key matches a given pattern.
       def delete_matched(matcher, options = nil)
         options = merged_options(options)
         instrument(:delete_matched, matcher.inspect) do
@@ -104,15 +108,15 @@ module ActiveSupport
         @monitor.synchronize(&block)
       end
 
-      protected
+      private
 
         PER_ENTRY_OVERHEAD = 240
 
-        def cached_size(key, entry) # :nodoc:
+        def cached_size(key, entry)
           key.to_s.bytesize + entry.size + PER_ENTRY_OVERHEAD
         end
 
-        def read_entry(key, options) # :nodoc:
+        def read_entry(key, options)
           entry = @data[key]
           synchronize do
             if entry
@@ -124,7 +128,7 @@ module ActiveSupport
           entry
         end
 
-        def write_entry(key, entry, options) # :nodoc:
+        def write_entry(key, entry, options)
           entry.dup_value!
           synchronize do
             old_entry = @data[key]
@@ -141,7 +145,7 @@ module ActiveSupport
           end
         end
 
-        def delete_entry(key, options) # :nodoc:
+        def delete_entry(key, options)
           synchronize do
             @key_access.delete(key)
             entry = @data.delete(key)
@@ -150,8 +154,6 @@ module ActiveSupport
           end
         end
 
-      private
-
         def modify_value(name, amount, options)
           synchronize do
             options = merged_options(options)
diff --git a/activesupport/lib/active_support/cache/null_store.rb b/activesupport/lib/active_support/cache/null_store.rb
index 0564ce5312..1a5983db43 100644
--- a/activesupport/lib/active_support/cache/null_store.rb
+++ b/activesupport/lib/active_support/cache/null_store.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActiveSupport
   module Cache
     # A cache store implementation which doesn't actually store anything. Useful in
@@ -25,15 +27,15 @@ module ActiveSupport
       def delete_matched(matcher, options = nil)
       end
 
-      protected
-        def read_entry(key, options) # :nodoc:
+      private
+        def read_entry(key, options)
         end
 
-        def write_entry(key, entry, options) # :nodoc:
+        def write_entry(key, entry, options)
           true
         end
 
-        def delete_entry(key, options) # :nodoc:
+        def delete_entry(key, options)
           false
         end
     end
diff --git a/activesupport/lib/active_support/cache/redis_cache_store.rb b/activesupport/lib/active_support/cache/redis_cache_store.rb
new file mode 100644
index 0000000000..6cc45f5284
--- /dev/null
+++ b/activesupport/lib/active_support/cache/redis_cache_store.rb
@@ -0,0 +1,406 @@
+# frozen_string_literal: true
+
+begin
+  gem "redis", ">= 4.0.1"
+  require "redis"
+  require "redis/distributed"
+rescue LoadError
+  warn "The Redis cache store requires the redis gem, version 4.0.1 or later. Please add it to your Gemfile: `gem \"redis\", \"~> 4.0\"`"
+  raise
+end
+
+# Prefer the hiredis driver but don't require it.
+begin
+  require "redis/connection/hiredis"
+rescue LoadError
+end
+
+require "digest/sha2"
+require "active_support/core_ext/marshal"
+
+module ActiveSupport
+  module Cache
+    # Redis cache store.
+    #
+    # Deployment note: Take care to use a *dedicated Redis cache* rather
+    # than pointing this at your existing Redis server. It won't cope well
+    # with mixed usage patterns and it won't expire cache entries by default.
+    #
+    # Redis cache server setup guide: https://redis.io/topics/lru-cache
+    #
+    # * Supports vanilla Redis, hiredis, and Redis::Distributed.
+    # * Supports Memcached-like sharding across Redises with Redis::Distributed.
+    # * Fault tolerant. If the Redis server is unavailable, no exceptions are
+    #   raised. Cache fetches are all misses and writes are dropped.
+    # * Local cache. Hot in-memory primary cache within block/middleware scope.
+    # * +read_multi+ and +write_multi+ support for Redis mget/mset. Use Redis::Distributed
+    #   4.0.1+ for distributed mget support.
+    # * +delete_matched+ support for Redis KEYS globs.
+    class RedisCacheStore < Store
+      # Keys are truncated with their own SHA2 digest if they exceed 1kB
+      MAX_KEY_BYTESIZE = 1024
+
+      DEFAULT_REDIS_OPTIONS = {
+        connect_timeout:    20,
+        read_timeout:       1,
+        write_timeout:      1,
+        reconnect_attempts: 0,
+      }
+
+      DEFAULT_ERROR_HANDLER = -> (method:, returning:, exception:) do
+        if logger
+          logger.error { "RedisCacheStore: #{method} failed, returned #{returning.inspect}: #{exception.class}: #{exception.message}" }
+        end
+      end
+
+      DELETE_GLOB_LUA = "for i, name in ipairs(redis.call('KEYS', ARGV[1])) do redis.call('DEL', name); end"
+      private_constant :DELETE_GLOB_LUA
+
+      # Support raw values in the local cache strategy.
+      module LocalCacheWithRaw # :nodoc:
+        private
+          def read_entry(key, options)
+            entry = super
+            if options[:raw] && local_cache && entry
+              entry = deserialize_entry(entry.value)
+            end
+            entry
+          end
+
+          def write_entry(key, entry, options)
+            if options[:raw] && local_cache
+              raw_entry = Entry.new(entry.value.to_s)
+              raw_entry.expires_at = entry.expires_at
+              super(key, raw_entry, options)
+            else
+              super
+            end
+          end
+
+          def write_multi_entries(entries, options)
+            if options[:raw] && local_cache
+              raw_entries = entries.map do |key, entry|
+                raw_entry = Entry.new(entry.value.to_s)
+                raw_entry.expires_at = entry.expires_at
+              end.to_h
+
+              super(raw_entries, options)
+            else
+              super
+            end
+          end
+      end
+
+      prepend Strategy::LocalCache
+      prepend LocalCacheWithRaw
+
+      class << self
+        # Factory method to create a new Redis instance.
+        #
+        # Handles four options: :redis block, :redis instance, single :url
+        # string, and multiple :url strings.
+        #
+        #   Option  Class       Result
+        #   :redis  Proc    ->  options[:redis].call
+        #   :redis  Object  ->  options[:redis]
+        #   :url    String  ->  Redis.new(url: …)
+        #   :url    Array   ->  Redis::Distributed.new([{ url: … }, { url: … }, …])
+        #
+        def build_redis(redis: nil, url: nil, **redis_options) #:nodoc:
+          urls = Array(url)
+
+          if redis.respond_to?(:call)
+            redis.call
+          elsif redis
+            redis
+          elsif urls.size > 1
+            build_redis_distributed_client urls: urls, **redis_options
+          else
+            build_redis_client url: urls.first, **redis_options
+          end
+        end
+
+        private
+          def build_redis_distributed_client(urls:, **redis_options)
+            ::Redis::Distributed.new([], DEFAULT_REDIS_OPTIONS.merge(redis_options)).tap do |dist|
+              urls.each { |u| dist.add_node url: u }
+            end
+          end
+
+          def build_redis_client(url:, **redis_options)
+            ::Redis.new DEFAULT_REDIS_OPTIONS.merge(redis_options.merge(url: url))
+          end
+      end
+
+      attr_reader :redis_options
+      attr_reader :max_key_bytesize
+
+      # Creates a new Redis cache store.
+      #
+      # Handles three options: block provided to instantiate, single URL
+      # provided, and multiple URLs provided.
+      #
+      #   :redis Proc   -> options[:redis].call
+      #   :url   String -> Redis.new(url: …)
+      #   :url   Array  -> Redis::Distributed.new([{ url: … }, { url: … }, …])
+      #
+      # No namespace is set by default. Provide one if the Redis cache
+      # server is shared with other apps: <tt>namespace: 'myapp-cache'<tt>.
+      #
+      # Compression is enabled by default with a 1kB threshold, so cached
+      # values larger than 1kB are automatically compressed. Disable by
+      # passing <tt>cache: false</tt> or change the threshold by passing
+      # <tt>compress_threshold: 4.kilobytes</tt>.
+      #
+      # No expiry is set on cache entries by default. Redis is expected to
+      # be configured with an eviction policy that automatically deletes
+      # least-recently or -frequently used keys when it reaches max memory.
+      # See https://redis.io/topics/lru-cache for cache server setup.
+      #
+      # Race condition TTL is not set by default. This can be used to avoid
+      # "thundering herd" cache writes when hot cache entries are expired.
+      # See <tt>ActiveSupport::Cache::Store#fetch</tt> for more.
+      def initialize(namespace: nil, compress: true, compress_threshold: 1.kilobyte, expires_in: nil, race_condition_ttl: nil, error_handler: DEFAULT_ERROR_HANDLER, **redis_options)
+        @redis_options = redis_options
+
+        @max_key_bytesize = MAX_KEY_BYTESIZE
+        @error_handler = error_handler
+
+        super namespace: namespace,
+          compress: compress, compress_threshold: compress_threshold,
+          expires_in: expires_in, race_condition_ttl: race_condition_ttl
+      end
+
+      def redis
+        @redis ||= self.class.build_redis(**redis_options)
+      end
+
+      def inspect
+        instance = @redis || @redis_options
+        "<##{self.class} options=#{options.inspect} redis=#{instance.inspect}>"
+      end
+
+      # Cache Store API implementation.
+      #
+      # Read multiple values at once. Returns a hash of requested keys ->
+      # fetched values.
+      def read_multi(*names)
+        if mget_capable?
+          read_multi_mget(*names)
+        else
+          super
+        end
+      end
+
+      # Cache Store API implementation.
+      #
+      # Supports Redis KEYS glob patterns:
+      #
+      #   h?llo matches hello, hallo and hxllo
+      #   h*llo matches hllo and heeeello
+      #   h[ae]llo matches hello and hallo, but not hillo
+      #   h[^e]llo matches hallo, hbllo, ... but not hello
+      #   h[a-b]llo matches hallo and hbllo
+      #
+      # Use \ to escape special characters if you want to match them verbatim.
+      #
+      # See https://redis.io/commands/KEYS for more.
+      #
+      # Failsafe: Raises errors.
+      def delete_matched(matcher, options = nil)
+        instrument :delete_matched, matcher do
+          case matcher
+          when String
+            redis.eval DELETE_GLOB_LUA, [], [namespace_key(matcher, options)]
+          else
+            raise ArgumentError, "Only Redis glob strings are supported: #{matcher.inspect}"
+          end
+        end
+      end
+
+      # Cache Store API implementation.
+      #
+      # Increment a cached value. This method uses the Redis incr atomic
+      # operator and can only be used on values written with the :raw option.
+      # Calling it on a value not stored with :raw will initialize that value
+      # to zero.
+      #
+      # Failsafe: Raises errors.
+      def increment(name, amount = 1, options = nil)
+        instrument :increment, name, amount: amount do
+          redis.incrby normalize_key(name, options), amount
+        end
+      end
+
+      # Cache Store API implementation.
+      #
+      # Decrement a cached value. This method uses the Redis decr atomic
+      # operator and can only be used on values written with the :raw option.
+      # Calling it on a value not stored with :raw will initialize that value
+      # to zero.
+      #
+      # Failsafe: Raises errors.
+      def decrement(name, amount = 1, options = nil)
+        instrument :decrement, name, amount: amount do
+          redis.decrby normalize_key(name, options), amount
+        end
+      end
+
+      # Cache Store API implementation.
+      #
+      # Removes expired entries. Handled natively by Redis least-recently-/
+      # least-frequently-used expiry, so manual cleanup is not supported.
+      def cleanup(options = nil)
+        super
+      end
+
+      # Clear the entire cache on all Redis servers. Safe to use on
+      # shared servers if the cache is namespaced.
+      #
+      # Failsafe: Raises errors.
+      def clear(options = nil)
+        failsafe :clear do
+          if namespace = merged_options(options)[namespace]
+            delete_matched "*", namespace: namespace
+          else
+            redis.flushdb
+          end
+        end
+      end
+
+      def mget_capable? #:nodoc:
+        set_redis_capabilities unless defined? @mget_capable
+        @mget_capable
+      end
+
+      def mset_capable? #:nodoc:
+        set_redis_capabilities unless defined? @mset_capable
+        @mset_capable
+      end
+
+      private
+        def set_redis_capabilities
+          case redis
+          when Redis::Distributed
+            @mget_capable = true
+            @mset_capable = false
+          else
+            @mget_capable = true
+            @mset_capable = true
+          end
+        end
+
+        # Store provider interface:
+        # Read an entry from the cache.
+        def read_entry(key, options = nil)
+          failsafe :read_entry do
+            deserialize_entry redis.get(key)
+          end
+        end
+
+        def read_multi_mget(*names)
+          options = names.extract_options!
+          options = merged_options(options)
+
+          keys = names.map { |name| normalize_key(name, options) }
+          values = redis.mget(*keys)
+
+          names.zip(values).each_with_object({}) do |(name, value), results|
+            if value
+              entry = deserialize_entry(value)
+              unless entry.nil? || entry.expired? || entry.mismatched?(normalize_version(name, options))
+                results[name] = entry.value
+              end
+            end
+          end
+        end
+
+        # Write an entry to the cache.
+        #
+        # Requires Redis 2.6.12+ for extended SET options.
+        def write_entry(key, entry, unless_exist: false, raw: false, expires_in: nil, race_condition_ttl: nil, **options)
+          value = raw ? entry.value.to_s : serialize_entry(entry)
+
+          # If race condition TTL is in use, ensure that cache entries
+          # stick around a bit longer after they would have expired
+          # so we can purposefully serve stale entries.
+          if race_condition_ttl && expires_in && expires_in > 0 && !raw
+            expires_in += 5.minutes
+          end
+
+          failsafe :write_entry do
+            if unless_exist || expires_in
+              modifiers = {}
+              modifiers[:nx] = unless_exist
+              modifiers[:px] = (1000 * expires_in.to_f).ceil if expires_in
+
+              redis.set key, value, modifiers
+            else
+              redis.set key, value
+            end
+          end
+        end
+
+        # Delete an entry from the cache.
+        def delete_entry(key, options)
+          failsafe :delete_entry, returning: false do
+            redis.del key
+          end
+        end
+
+        # Nonstandard store provider API to write multiple values at once.
+        def write_multi_entries(entries, expires_in: nil, **options)
+          if entries.any?
+            if mset_capable? && expires_in.nil?
+              failsafe :write_multi_entries do
+                redis.mapped_mset(entries)
+              end
+            else
+              super
+            end
+          end
+        end
+
+        # Truncate keys that exceed 1kB.
+        def normalize_key(key, options)
+          truncate_key super
+        end
+
+        def truncate_key(key)
+          if key.bytesize > max_key_bytesize
+            suffix = ":sha2:#{Digest::SHA2.hexdigest(key)}"
+            truncate_at = max_key_bytesize - suffix.bytesize
+            "#{key.byteslice(0, truncate_at)}#{suffix}"
+          else
+            key
+          end
+        end
+
+        def deserialize_entry(raw_value)
+          if raw_value
+            entry = Marshal.load(raw_value) rescue raw_value
+            entry.is_a?(Entry) ? entry : Entry.new(entry)
+          end
+        end
+
+        def serialize_entry(entry)
+          Marshal.dump(entry)
+        end
+
+        def failsafe(method, returning: nil)
+          yield
+        rescue ::Redis::BaseConnectionError => e
+          handle_exception exception: e, method: method, returning: returning
+          returning
+        end
+
+        def handle_exception(exception:, method:, returning:)
+          if @error_handler
+            @error_handler.(method: method, exception: exception, returning: returning)
+          end
+        rescue => failsafe
+          warn "RedisCacheStore ignored exception in handle_exception: #{failsafe.class}: #{failsafe.message}\n  #{failsafe.backtrace.join("\n  ")}"
+        end
+    end
+  end
+end
diff --git a/activesupport/lib/active_support/cache/strategy/local_cache.rb b/activesupport/lib/active_support/cache/strategy/local_cache.rb
index 1c678dc2af..aaa9638fa8 100644
--- a/activesupport/lib/active_support/cache/strategy/local_cache.rb
+++ b/activesupport/lib/active_support/cache/strategy/local_cache.rb
@@ -1,6 +1,8 @@
-require 'active_support/core_ext/object/duplicable'
-require 'active_support/core_ext/string/inflections'
-require 'active_support/per_thread_registry'
+# frozen_string_literal: true
+
+require "active_support/core_ext/object/duplicable"
+require "active_support/core_ext/string/inflections"
+require "active_support/per_thread_registry"
 
 module ActiveSupport
   module Cache
@@ -9,7 +11,7 @@ module ActiveSupport
       # duration of a block. Repeated calls to the cache for the same key will hit the
       # in-memory cache for faster access.
       module LocalCache
-        autoload :Middleware, 'active_support/cache/strategy/local_cache_middleware'
+        autoload :Middleware, "active_support/cache/strategy/local_cache_middleware"
 
         # Class for storing and registering the local caches.
         class LocalCacheRegistry # :nodoc:
@@ -70,6 +72,7 @@ module ActiveSupport
         def with_local_cache
           use_temporary_local_cache(LocalStore.new) { yield }
         end
+
         # Middleware class can be inserted as a Rack handler to be local cache for the
         # duration of request.
         def middleware
@@ -86,26 +89,26 @@ module ActiveSupport
 
         def cleanup(options = nil) # :nodoc:
           return super unless cache = local_cache
-          cache.clear(options)
+          cache.clear
           super
         end
 
         def increment(name, amount = 1, options = nil) # :nodoc:
           return super unless local_cache
-          value = bypass_local_cache{super}
+          value = bypass_local_cache { super }
           write_cache_value(name, value, options)
           value
         end
 
         def decrement(name, amount = 1, options = nil) # :nodoc:
           return super unless local_cache
-          value = bypass_local_cache{super}
+          value = bypass_local_cache { super }
           write_cache_value(name, value, options)
           value
         end
 
-        protected
-          def read_entry(key, options) # :nodoc:
+        private
+          def read_entry(key, options)
             if cache = local_cache
               cache.fetch_entry(key) { super }
             else
@@ -113,25 +116,22 @@ module ActiveSupport
             end
           end
 
-          def write_entry(key, entry, options) # :nodoc:
-            local_cache.write_entry(key, entry, options) if local_cache
+          def write_entry(key, entry, options)
+            if options[:unless_exist]
+              local_cache.delete_entry(key, options) if local_cache
+            else
+              local_cache.write_entry(key, entry, options) if local_cache
+            end
+
             super
           end
 
-          def delete_entry(key, options) # :nodoc:
+          def delete_entry(key, options)
             local_cache.delete_entry(key, options) if local_cache
             super
           end
 
-          def set_cache_value(value, name, amount, options) # :nodoc:
-            ActiveSupport::Deprecation.warn(<<-MESSAGE.strip_heredoc)
-              `set_cache_value` is deprecated and will be removed from Rails 5.1.
-              Please use `write_cache_value` instead.
-            MESSAGE
-            write_cache_value name, value, options
-          end
-
-          def write_cache_value(name, value, options) # :nodoc:
+          def write_cache_value(name, value, options)
             name = normalize_key(name, options)
             cache = local_cache
             cache.mute do
@@ -143,10 +143,8 @@ module ActiveSupport
             end
           end
 
-        private
-
           def local_cache_key
-            @local_cache_key ||= "#{self.class.name.underscore}_local_cache_#{object_id}".gsub(/[\/-]/, '_').to_sym
+            @local_cache_key ||= "#{self.class.name.underscore}_local_cache_#{object_id}".gsub(/[\/-]/, "_").to_sym
           end
 
           def local_cache
diff --git a/activesupport/lib/active_support/cache/strategy/local_cache_middleware.rb b/activesupport/lib/active_support/cache/strategy/local_cache_middleware.rb
index a6f24b1a3c..62542bdb22 100644
--- a/activesupport/lib/active_support/cache/strategy/local_cache_middleware.rb
+++ b/activesupport/lib/active_support/cache/strategy/local_cache_middleware.rb
@@ -1,11 +1,12 @@
-require 'rack/body_proxy'
-require 'rack/utils'
+# frozen_string_literal: true
+
+require "rack/body_proxy"
+require "rack/utils"
 
 module ActiveSupport
   module Cache
     module Strategy
       module LocalCache
-
         #--
         # This class wraps up local storage for middlewares. Only the middleware method should
         # construct them.
@@ -13,9 +14,9 @@ module ActiveSupport
           attr_reader :name, :local_cache_key
 
           def initialize(name, local_cache_key)
-            @name             = name
+            @name = name
             @local_cache_key = local_cache_key
-            @app              = nil
+            @app = nil
           end
 
           def new(app)
@@ -29,13 +30,13 @@ module ActiveSupport
             response[2] = ::Rack::BodyProxy.new(response[2]) do
               LocalCacheRegistry.set_cache_for(local_cache_key, nil)
             end
+            cleanup_on_body_close = true
             response
           rescue Rack::Utils::InvalidParameterError
-            LocalCacheRegistry.set_cache_for(local_cache_key, nil)
             [400, {}, []]
-          rescue Exception
-            LocalCacheRegistry.set_cache_for(local_cache_key, nil)
-            raise
+          ensure
+            LocalCacheRegistry.set_cache_for(local_cache_key, nil) unless
+              cleanup_on_body_close
           end
         end
       end
diff --git a/activesupport/lib/active_support/callbacks.rb b/activesupport/lib/active_support/callbacks.rb
index 557a4695a6..0ed4681b7d 100644
--- a/activesupport/lib/active_support/callbacks.rb
+++ b/activesupport/lib/active_support/callbacks.rb
@@ -1,13 +1,14 @@
-require 'active_support/concern'
-require 'active_support/descendants_tracker'
-require 'active_support/core_ext/array/extract_options'
-require 'active_support/core_ext/class/attribute'
-require 'active_support/core_ext/kernel/reporting'
-require 'active_support/core_ext/kernel/singleton_class'
-require 'active_support/core_ext/module/attribute_accessors'
-require 'active_support/core_ext/string/filters'
-require 'active_support/deprecation'
-require 'thread'
+# frozen_string_literal: true
+
+require "active_support/concern"
+require "active_support/descendants_tracker"
+require "active_support/core_ext/array/extract_options"
+require "active_support/core_ext/class/attribute"
+require "active_support/core_ext/kernel/reporting"
+require "active_support/core_ext/kernel/singleton_class"
+require "active_support/core_ext/string/filters"
+require "active_support/deprecation"
+require "thread"
 
 module ActiveSupport
   # Callbacks are code hooks that are run at key points in an object's life cycle.
@@ -63,16 +64,11 @@ module ActiveSupport
 
     included do
       extend ActiveSupport::DescendantsTracker
+      class_attribute :__callbacks, instance_writer: false, default: {}
     end
 
     CALLBACK_FILTER_TYPES = [:before, :after, :around]
 
-    # If true, Active Record and Active Model callbacks returning +false+ will
-    # halt the entire callback chain and display a deprecation message.
-    # If false, callback chains will only be halted by calling +throw :abort+.
-    # Defaults to +true+.
-    mattr_accessor(:halt_and_display_warning_on_return_false, instance_writer: false) { true }
-
     # Runs the callbacks for the given event.
     #
     # Calls the before and around callbacks in the order they were set, yields
@@ -86,711 +82,764 @@ module ActiveSupport
     #   run_callbacks :save do
     #     save
     #   end
-    def run_callbacks(kind, &block)
-      send "_run_#{kind}_callbacks", &block
-    end
-
-    private
+    #
+    #--
+    #
+    # As this method is used in many places, and often wraps large portions of
+    # user code, it has an additional design goal of minimizing its impact on
+    # the visible call stack. An exception from inside a :before or :after
+    # callback can be as noisy as it likes -- but when control has passed
+    # smoothly through and into the supplied block, we want as little evidence
+    # as possible that we were here.
+    def run_callbacks(kind)
+      callbacks = __callbacks[kind.to_sym]
 
-    def __run_callbacks__(callbacks, &block)
       if callbacks.empty?
         yield if block_given?
       else
-        runner = callbacks.compile
-        e = Filters::Environment.new(self, false, nil, block)
-        runner.call(e).value
-      end
-    end
-
-    # A hook invoked every time a before callback is halted.
-    # This can be overridden in ActiveSupport::Callbacks implementors in order
-    # to provide better debugging/logging.
-    def halted_callback_hook(filter)
-    end
+        env = Filters::Environment.new(self, false, nil)
+        next_sequence = callbacks.compile
+
+        invoke_sequence = Proc.new do
+          skipped = nil
+          while true
+            current = next_sequence
+            current.invoke_before(env)
+            if current.final?
+              env.value = !env.halted && (!block_given? || yield)
+            elsif current.skip?(env)
+              (skipped ||= []) << current
+              next_sequence = next_sequence.nested
+              next
+            else
+              next_sequence = next_sequence.nested
+              begin
+                target, block, method, *arguments = current.expand_call_template(env, invoke_sequence)
+                target.send(method, *arguments, &block)
+              ensure
+                next_sequence = current
+              end
+            end
+            current.invoke_after(env)
+            skipped.pop.invoke_after(env) while skipped && skipped.first
+            break env.value
+          end
+        end
 
-    module Conditionals # :nodoc:
-      class Value
-        def initialize(&block)
-          @block = block
+        # Common case: no 'around' callbacks defined
+        if next_sequence.final?
+          next_sequence.invoke_before(env)
+          env.value = !env.halted && (!block_given? || yield)
+          next_sequence.invoke_after(env)
+          env.value
+        else
+          invoke_sequence.call
         end
-        def call(target, value); @block.call(value); end
       end
     end
 
-    module Filters
-      Environment = Struct.new(:target, :halted, :value, :run_block)
+    private
 
-      class End
-        def call(env)
-          block = env.run_block
-          env.value = !env.halted && (!block || block.call)
-          env
-        end
+      # A hook invoked every time a before callback is halted.
+      # This can be overridden in ActiveSupport::Callbacks implementors in order
+      # to provide better debugging/logging.
+      def halted_callback_hook(filter)
       end
-      ENDING = End.new
 
-      class Before
-        def self.build(callback_sequence, user_callback, user_conditions, chain_config, filter)
-          halted_lambda = chain_config[:terminator]
-
-          if user_conditions.any?
-            halting_and_conditional(callback_sequence, user_callback, user_conditions, halted_lambda, filter)
-          else
-            halting(callback_sequence, user_callback, halted_lambda, filter)
+      module Conditionals # :nodoc:
+        class Value
+          def initialize(&block)
+            @block = block
           end
+          def call(target, value); @block.call(value); end
         end
+      end
 
-        def self.halting_and_conditional(callback_sequence, user_callback, user_conditions, halted_lambda, filter)
-          callback_sequence.before do |env|
-            target = env.target
-            value  = env.value
-            halted = env.halted
+      module Filters
+        Environment = Struct.new(:target, :halted, :value)
 
-            if !halted && user_conditions.all? { |c| c.call(target, value) }
-              result_lambda = -> { user_callback.call target, value }
-              env.halted = halted_lambda.call(target, result_lambda)
-              if env.halted
-                target.send :halted_callback_hook, filter
-              end
+        class Before
+          def self.build(callback_sequence, user_callback, user_conditions, chain_config, filter)
+            halted_lambda = chain_config[:terminator]
+
+            if user_conditions.any?
+              halting_and_conditional(callback_sequence, user_callback, user_conditions, halted_lambda, filter)
+            else
+              halting(callback_sequence, user_callback, halted_lambda, filter)
             end
+          end
 
-            env
+          def self.halting_and_conditional(callback_sequence, user_callback, user_conditions, halted_lambda, filter)
+            callback_sequence.before do |env|
+              target = env.target
+              value  = env.value
+              halted = env.halted
+
+              if !halted && user_conditions.all? { |c| c.call(target, value) }
+                result_lambda = -> { user_callback.call target, value }
+                env.halted = halted_lambda.call(target, result_lambda)
+                if env.halted
+                  target.send :halted_callback_hook, filter
+                end
+              end
+
+              env
+            end
           end
-        end
-        private_class_method :halting_and_conditional
+          private_class_method :halting_and_conditional
 
-        def self.halting(callback_sequence, user_callback, halted_lambda, filter)
-          callback_sequence.before do |env|
-            target = env.target
-            value  = env.value
-            halted = env.halted
+          def self.halting(callback_sequence, user_callback, halted_lambda, filter)
+            callback_sequence.before do |env|
+              target = env.target
+              value  = env.value
+              halted = env.halted
 
-            unless halted
-              result_lambda = -> { user_callback.call target, value }
-              env.halted = halted_lambda.call(target, result_lambda)
+              unless halted
+                result_lambda = -> { user_callback.call target, value }
+                env.halted = halted_lambda.call(target, result_lambda)
 
-              if env.halted
-                target.send :halted_callback_hook, filter
+                if env.halted
+                  target.send :halted_callback_hook, filter
+                end
               end
-            end
 
-            env
+              env
+            end
           end
+          private_class_method :halting
         end
-        private_class_method :halting
-      end
 
-      class After
-        def self.build(callback_sequence, user_callback, user_conditions, chain_config)
-          if chain_config[:skip_after_callbacks_if_terminated]
-            if user_conditions.any?
-              halting_and_conditional(callback_sequence, user_callback, user_conditions)
+        class After
+          def self.build(callback_sequence, user_callback, user_conditions, chain_config)
+            if chain_config[:skip_after_callbacks_if_terminated]
+              if user_conditions.any?
+                halting_and_conditional(callback_sequence, user_callback, user_conditions)
+              else
+                halting(callback_sequence, user_callback)
+              end
             else
-              halting(callback_sequence, user_callback)
+              if user_conditions.any?
+                conditional callback_sequence, user_callback, user_conditions
+              else
+                simple callback_sequence, user_callback
+              end
             end
-          else
-            if user_conditions.any?
-              conditional callback_sequence, user_callback, user_conditions
-            else
-              simple callback_sequence, user_callback
+          end
+
+          def self.halting_and_conditional(callback_sequence, user_callback, user_conditions)
+            callback_sequence.after do |env|
+              target = env.target
+              value  = env.value
+              halted = env.halted
+
+              if !halted && user_conditions.all? { |c| c.call(target, value) }
+                user_callback.call target, value
+              end
+
+              env
             end
           end
-        end
+          private_class_method :halting_and_conditional
 
-        def self.halting_and_conditional(callback_sequence, user_callback, user_conditions)
-          callback_sequence.after do |env|
-            target = env.target
-            value  = env.value
-            halted = env.halted
+          def self.halting(callback_sequence, user_callback)
+            callback_sequence.after do |env|
+              unless env.halted
+                user_callback.call env.target, env.value
+              end
 
-            if !halted && user_conditions.all? { |c| c.call(target, value) }
-              user_callback.call target, value
+              env
             end
+          end
+          private_class_method :halting
+
+          def self.conditional(callback_sequence, user_callback, user_conditions)
+            callback_sequence.after do |env|
+              target = env.target
+              value  = env.value
 
-            env
+              if user_conditions.all? { |c| c.call(target, value) }
+                user_callback.call target, value
+              end
+
+              env
+            end
           end
-        end
-        private_class_method :halting_and_conditional
+          private_class_method :conditional
 
-        def self.halting(callback_sequence, user_callback)
-          callback_sequence.after do |env|
-            unless env.halted
+          def self.simple(callback_sequence, user_callback)
+            callback_sequence.after do |env|
               user_callback.call env.target, env.value
+
+              env
             end
+          end
+          private_class_method :simple
+        end
+      end
 
-            env
+      class Callback #:nodoc:#
+        def self.build(chain, filter, kind, options)
+          if filter.is_a?(String)
+            raise ArgumentError, <<-MSG.squish
+              Passing string to define a callback is not supported. See the `.set_callback`
+              documentation to see supported values.
+            MSG
           end
+
+          new chain.name, filter, kind, options, chain.config
         end
-        private_class_method :halting
 
-        def self.conditional(callback_sequence, user_callback, user_conditions)
-          callback_sequence.after do |env|
-            target = env.target
-            value  = env.value
+        attr_accessor :kind, :name
+        attr_reader :chain_config
+
+        def initialize(name, filter, kind, options, chain_config)
+          @chain_config = chain_config
+          @name    = name
+          @kind    = kind
+          @filter  = filter
+          @key     = compute_identifier filter
+          @if      = check_conditionals(Array(options[:if]))
+          @unless  = check_conditionals(Array(options[:unless]))
+        end
 
-            if user_conditions.all? { |c| c.call(target, value) }
-              user_callback.call target, value
-            end
+        def filter; @key; end
+        def raw_filter; @filter; end
 
-            env
-          end
+        def merge_conditional_options(chain, if_option:, unless_option:)
+          options = {
+            if: @if.dup,
+            unless: @unless.dup
+          }
+
+          options[:if].concat     Array(unless_option)
+          options[:unless].concat Array(if_option)
+
+          self.class.build chain, @filter, @kind, options
         end
-        private_class_method :conditional
 
-        def self.simple(callback_sequence, user_callback)
-          callback_sequence.after do |env|
-            user_callback.call env.target, env.value
+        def matches?(_kind, _filter)
+          @kind == _kind && filter == _filter
+        end
 
-            env
+        def duplicates?(other)
+          case @filter
+          when Symbol
+            matches?(other.kind, other.filter)
+          else
+            false
           end
         end
-        private_class_method :simple
-      end
 
-      class Around
-        def self.build(callback_sequence, user_callback, user_conditions, chain_config)
-          if user_conditions.any?
-            halting_and_conditional(callback_sequence, user_callback, user_conditions)
-          else
-            halting(callback_sequence, user_callback)
+        # Wraps code with filter
+        def apply(callback_sequence)
+          user_conditions = conditions_lambdas
+          user_callback = CallTemplate.build(@filter, self)
+
+          case kind
+          when :before
+            Filters::Before.build(callback_sequence, user_callback.make_lambda, user_conditions, chain_config, @filter)
+          when :after
+            Filters::After.build(callback_sequence, user_callback.make_lambda, user_conditions, chain_config)
+          when :around
+            callback_sequence.around(user_callback, user_conditions)
           end
         end
 
-        def self.halting_and_conditional(callback_sequence, user_callback, user_conditions)
-          callback_sequence.around do |env, &run|
-            target = env.target
-            value  = env.value
-            halted = env.halted
+        def current_scopes
+          Array(chain_config[:scope]).map { |s| public_send(s) }
+        end
 
-            if !halted && user_conditions.all? { |c| c.call(target, value) }
-              user_callback.call(target, value) {
-                run.call.value
-              }
-              env
-            else
-              run.call
+        private
+          def check_conditionals(conditionals)
+            if conditionals.any? { |c| c.is_a?(String) }
+              raise ArgumentError, <<-MSG.squish
+                Passing string to be evaluated in :if and :unless conditional
+                options is not supported. Pass a symbol for an instance method,
+                or a lambda, proc or block, instead.
+              MSG
             end
-          end
-        end
-        private_class_method :halting_and_conditional
 
-        def self.halting(callback_sequence, user_callback)
-          callback_sequence.around do |env, &run|
-            target = env.target
-            value  = env.value
+            conditionals
+          end
 
-            if env.halted
-              run.call
+          def compute_identifier(filter)
+            case filter
+            when ::Proc
+              filter.object_id
             else
-              user_callback.call(target, value) {
-                run.call.value
-              }
-              env
+              filter
             end
           end
-        end
-        private_class_method :halting
+
+          def conditions_lambdas
+            @if.map { |c| CallTemplate.build(c, self).make_lambda } +
+              @unless.map { |c| CallTemplate.build(c, self).inverted_lambda }
+          end
       end
-    end
 
-    class Callback #:nodoc:#
-      def self.build(chain, filter, kind, options)
-        if filter.is_a?(String)
-          ActiveSupport::Deprecation.warn(<<-MSG.squish)
-            Passing string to define callback is deprecated and will be removed
-            in Rails 5.1 without replacement.
-          MSG
+      # A future invocation of user-supplied code (either as a callback,
+      # or a condition filter).
+      class CallTemplate # :nodoc:
+        def initialize(target, method, arguments, block)
+          @override_target = target
+          @method_name = method
+          @arguments = arguments
+          @override_block = block
         end
 
-        new chain.name, filter, kind, options, chain.config
-      end
+        # Return the parts needed to make this call, with the given
+        # input values.
+        #
+        # Returns an array of the form:
+        #
+        #   [target, block, method, *arguments]
+        #
+        # This array can be used as such:
+        #
+        #   target.send(method, *arguments, &block)
+        #
+        # The actual invocation is left up to the caller to minimize
+        # call stack pollution.
+        def expand(target, value, block)
+          result = @arguments.map { |arg|
+            case arg
+            when :value; value
+            when :target; target
+            when :block; block || raise(ArgumentError)
+            end
+          }
 
-      attr_accessor :kind, :name
-      attr_reader :chain_config
-
-      def initialize(name, filter, kind, options, chain_config)
-        @chain_config  = chain_config
-        @name    = name
-        @kind    = kind
-        @filter  = filter
-        @key     = compute_identifier filter
-        @if      = Array(options[:if])
-        @unless  = Array(options[:unless])
-      end
+          result.unshift @method_name
+          result.unshift @override_block || block
+          result.unshift @override_target || target
 
-      def filter; @key; end
-      def raw_filter; @filter; end
+          # target, block, method, *arguments = result
+          # target.send(method, *arguments, &block)
+          result
+        end
 
-      def merge_conditional_options(chain, if_option:, unless_option:)
-        options = {
-          :if     => @if.dup,
-          :unless => @unless.dup
-        }
+        # Return a lambda that will make this call when given the input
+        # values.
+        def make_lambda
+          lambda do |target, value, &block|
+            target, block, method, *arguments = expand(target, value, block)
+            target.send(method, *arguments, &block)
+          end
+        end
 
-        options[:if].concat     Array(unless_option)
-        options[:unless].concat Array(if_option)
+        # Return a lambda that will make this call when given the input
+        # values, but then return the boolean inverse of that result.
+        def inverted_lambda
+          lambda do |target, value, &block|
+            target, block, method, *arguments = expand(target, value, block)
+            ! target.send(method, *arguments, &block)
+          end
+        end
 
-        self.class.build chain, @filter, @kind, options
-      end
+        # Filters support:
+        #
+        #   Symbols:: A method to call.
+        #   Procs::   A proc to call with the object.
+        #   Objects:: An object with a <tt>before_foo</tt> method on it to call.
+        #
+        # All of these objects are converted into a CallTemplate and handled
+        # the same after this point.
+        def self.build(filter, callback)
+          case filter
+          when Symbol
+            new(nil, filter, [], nil)
+          when Conditionals::Value
+            new(filter, :call, [:target, :value], nil)
+          when ::Proc
+            if filter.arity > 1
+              new(nil, :instance_exec, [:target, :block], filter)
+            elsif filter.arity > 0
+              new(nil, :instance_exec, [:target], filter)
+            else
+              new(nil, :instance_exec, [], filter)
+            end
+          else
+            method_to_call = callback.current_scopes.join("_")
 
-      def matches?(_kind, _filter)
-        @kind == _kind && filter == _filter
+            new(filter, method_to_call, [:target], nil)
+          end
+        end
       end
 
-      def duplicates?(other)
-        case @filter
-        when Symbol, String
-          matches?(other.kind, other.filter)
-        else
-          false
+      # Execute before and after filters in a sequence instead of
+      # chaining them with nested lambda calls, see:
+      # https://github.com/rails/rails/issues/18011
+      class CallbackSequence # :nodoc:
+        def initialize(nested = nil, call_template = nil, user_conditions = nil)
+          @nested = nested
+          @call_template = call_template
+          @user_conditions = user_conditions
+
+          @before = []
+          @after = []
         end
-      end
 
-      # Wraps code with filter
-      def apply(callback_sequence)
-        user_conditions = conditions_lambdas
-        user_callback = make_lambda @filter
+        def before(&before)
+          @before.unshift(before)
+          self
+        end
 
-        case kind
-        when :before
-          Filters::Before.build(callback_sequence, user_callback, user_conditions, chain_config, @filter)
-        when :after
-          Filters::After.build(callback_sequence, user_callback, user_conditions, chain_config)
-        when :around
-          Filters::Around.build(callback_sequence, user_callback, user_conditions, chain_config)
+        def after(&after)
+          @after.push(after)
+          self
         end
-      end
 
-      private
+        def around(call_template, user_conditions)
+          CallbackSequence.new(self, call_template, user_conditions)
+        end
 
-      def invert_lambda(l)
-        lambda { |*args, &blk| !l.call(*args, &blk) }
-      end
+        def skip?(arg)
+          arg.halted || !@user_conditions.all? { |c| c.call(arg.target, arg.value) }
+        end
 
-      # Filters support:
-      #
-      #   Symbols:: A method to call.
-      #   Strings:: Some content to evaluate.
-      #   Procs::   A proc to call with the object.
-      #   Objects:: An object with a <tt>before_foo</tt> method on it to call.
-      #
-      # All of these objects are converted into a lambda and handled
-      # the same after this point.
-      def make_lambda(filter)
-        case filter
-        when Symbol
-          lambda { |target, _, &blk| target.send filter, &blk }
-        when String
-          l = eval "lambda { |value| #{filter} }"
-          lambda { |target, value| target.instance_exec(value, &l) }
-        when Conditionals::Value then filter
-        when ::Proc
-          if filter.arity > 1
-            return lambda { |target, _, &block|
-              raise ArgumentError unless block
-              target.instance_exec(target, block, &filter)
-            }
-          end
-
-          if filter.arity <= 0
-            lambda { |target, _| target.instance_exec(&filter) }
-          else
-            lambda { |target, _| target.instance_exec(target, &filter) }
-          end
-        else
-          scopes = Array(chain_config[:scope])
-          method_to_call = scopes.map{ |s| public_send(s) }.join("_")
+        def nested
+          @nested
+        end
 
-          lambda { |target, _, &blk|
-            filter.public_send method_to_call, target, &blk
-          }
+        def final?
+          !@call_template
         end
-      end
 
-      def compute_identifier(filter)
-        case filter
-        when String, ::Proc
-          filter.object_id
-        else
-          filter
+        def expand_call_template(arg, block)
+          @call_template.expand(arg.target, arg.value, block)
         end
-      end
 
-      def conditions_lambdas
-        @if.map { |c| make_lambda c } +
-          @unless.map { |c| invert_lambda make_lambda c }
-      end
-    end
+        def invoke_before(arg)
+          @before.each { |b| b.call(arg) }
+        end
 
-    # Execute before and after filters in a sequence instead of
-    # chaining them with nested lambda calls, see:
-    # https://github.com/rails/rails/issues/18011
-    class CallbackSequence
-      def initialize(&call)
-        @call = call
-        @before = []
-        @after = []
+        def invoke_after(arg)
+          @after.each { |a| a.call(arg) }
+        end
       end
 
-      def before(&before)
-        @before.unshift(before)
-        self
-      end
+      class CallbackChain #:nodoc:#
+        include Enumerable
 
-      def after(&after)
-        @after.push(after)
-        self
-      end
+        attr_reader :name, :config
 
-      def around(&around)
-        CallbackSequence.new do |arg|
-          around.call(arg) {
-            self.call(arg)
-          }
+        def initialize(name, config)
+          @name = name
+          @config = {
+            scope: [:kind],
+            terminator: default_terminator
+          }.merge!(config)
+          @chain = []
+          @callbacks = nil
+          @mutex = Mutex.new
         end
-      end
 
-      def call(arg)
-        @before.each { |b| b.call(arg) }
-        value = @call.call(arg)
-        @after.each { |a| a.call(arg) }
-        value
-      end
-    end
+        def each(&block); @chain.each(&block); end
+        def index(o);     @chain.index(o); end
+        def empty?;       @chain.empty?; end
 
-    # An Array with a compile method.
-    class CallbackChain #:nodoc:#
-      include Enumerable
-
-      attr_reader :name, :config
-
-      def initialize(name, config)
-        @name = name
-        @config = {
-          scope: [:kind],
-          terminator: default_terminator
-        }.merge!(config)
-        @chain = []
-        @callbacks = nil
-        @mutex = Mutex.new
-      end
+        def insert(index, o)
+          @callbacks = nil
+          @chain.insert(index, o)
+        end
 
-      def each(&block); @chain.each(&block); end
-      def index(o);     @chain.index(o); end
-      def empty?;       @chain.empty?; end
+        def delete(o)
+          @callbacks = nil
+          @chain.delete(o)
+        end
 
-      def insert(index, o)
-        @callbacks = nil
-        @chain.insert(index, o)
-      end
+        def clear
+          @callbacks = nil
+          @chain.clear
+          self
+        end
 
-      def delete(o)
-        @callbacks = nil
-        @chain.delete(o)
-      end
+        def initialize_copy(other)
+          @callbacks = nil
+          @chain     = other.chain.dup
+          @mutex     = Mutex.new
+        end
 
-      def clear
-        @callbacks = nil
-        @chain.clear
-        self
-      end
+        def compile
+          @callbacks || @mutex.synchronize do
+            final_sequence = CallbackSequence.new
+            @callbacks ||= @chain.reverse.inject(final_sequence) do |callback_sequence, callback|
+              callback.apply callback_sequence
+            end
+          end
+        end
 
-      def initialize_copy(other)
-        @callbacks = nil
-        @chain     = other.chain.dup
-        @mutex     = Mutex.new
-      end
+        def append(*callbacks)
+          callbacks.each { |c| append_one(c) }
+        end
 
-      def compile
-        @callbacks || @mutex.synchronize do
-          final_sequence = CallbackSequence.new { |env| Filters::ENDING.call(env) }
-          @callbacks ||= @chain.reverse.inject(final_sequence) do |callback_sequence, callback|
-            callback.apply callback_sequence
-          end
+        def prepend(*callbacks)
+          callbacks.each { |c| prepend_one(c) }
         end
-      end
 
-      def append(*callbacks)
-        callbacks.each { |c| append_one(c) }
-      end
+        protected
+          def chain; @chain; end
 
-      def prepend(*callbacks)
-        callbacks.each { |c| prepend_one(c) }
-      end
+        private
 
-      protected
-      def chain; @chain; end
+          def append_one(callback)
+            @callbacks = nil
+            remove_duplicates(callback)
+            @chain.push(callback)
+          end
 
-      private
+          def prepend_one(callback)
+            @callbacks = nil
+            remove_duplicates(callback)
+            @chain.unshift(callback)
+          end
 
-      def append_one(callback)
-        @callbacks = nil
-        remove_duplicates(callback)
-        @chain.push(callback)
-      end
+          def remove_duplicates(callback)
+            @callbacks = nil
+            @chain.delete_if { |c| callback.duplicates?(c) }
+          end
 
-      def prepend_one(callback)
-        @callbacks = nil
-        remove_duplicates(callback)
-        @chain.unshift(callback)
+          def default_terminator
+            Proc.new do |target, result_lambda|
+              terminate = true
+              catch(:abort) do
+                result_lambda.call
+                terminate = false
+              end
+              terminate
+            end
+          end
       end
 
-      def remove_duplicates(callback)
-        @callbacks = nil
-        @chain.delete_if { |c| callback.duplicates?(c) }
-      end
+      module ClassMethods
+        def normalize_callback_params(filters, block) # :nodoc:
+          type = CALLBACK_FILTER_TYPES.include?(filters.first) ? filters.shift : :before
+          options = filters.extract_options!
+          filters.unshift(block) if block
+          [type, filters, options.dup]
+        end
 
-      def default_terminator
-        Proc.new do |target, result_lambda|
-          terminate = true
-          catch(:abort) do
-            result_lambda.call if result_lambda.is_a?(Proc)
-            terminate = false
+        # This is used internally to append, prepend and skip callbacks to the
+        # CallbackChain.
+        def __update_callbacks(name) #:nodoc:
+          ([self] + ActiveSupport::DescendantsTracker.descendants(self)).reverse_each do |target|
+            chain = target.get_callbacks name
+            yield target, chain.dup
           end
-          terminate
         end
-      end
-    end
 
-    module ClassMethods
-      def normalize_callback_params(filters, block) # :nodoc:
-        type = CALLBACK_FILTER_TYPES.include?(filters.first) ? filters.shift : :before
-        options = filters.extract_options!
-        filters.unshift(block) if block
-        [type, filters, options.dup]
-      end
+        # Install a callback for the given event.
+        #
+        #   set_callback :save, :before, :before_method
+        #   set_callback :save, :after,  :after_method, if: :condition
+        #   set_callback :save, :around, ->(r, block) { stuff; result = block.call; stuff }
+        #
+        # The second argument indicates whether the callback is to be run +:before+,
+        # +:after+, or +:around+ the event. If omitted, +:before+ is assumed. This
+        # means the first example above can also be written as:
+        #
+        #   set_callback :save, :before_method
+        #
+        # The callback can be specified as a symbol naming an instance method; as a
+        # proc, lambda, or block; or as an object that responds to a certain method
+        # determined by the <tt>:scope</tt> argument to +define_callbacks+.
+        #
+        # If a proc, lambda, or block is given, its body is evaluated in the context
+        # of the current object. It can also optionally accept the current object as
+        # an argument.
+        #
+        # Before and around callbacks are called in the order that they are set;
+        # after callbacks are called in the reverse order.
+        #
+        # Around callbacks can access the return value from the event, if it
+        # wasn't halted, from the +yield+ call.
+        #
+        # ===== Options
+        #
+        # * <tt>:if</tt> - A symbol or an array of symbols, each naming an instance
+        #   method or a proc; the callback will be called only when they all return
+        #   a true value.
+        # * <tt>:unless</tt> - A symbol or an array of symbols, each naming an
+        #   instance method or a proc; the callback will be called only when they
+        #   all return a false value.
+        # * <tt>:prepend</tt> - If +true+, the callback will be prepended to the
+        #   existing chain rather than appended.
+        def set_callback(name, *filter_list, &block)
+          type, filters, options = normalize_callback_params(filter_list, block)
+
+          self_chain = get_callbacks name
+          mapped = filters.map do |filter|
+            Callback.build(self_chain, filter, type, options)
+          end
 
-      # This is used internally to append, prepend and skip callbacks to the
-      # CallbackChain.
-      def __update_callbacks(name) #:nodoc:
-        ([self] + ActiveSupport::DescendantsTracker.descendants(self)).reverse_each do |target|
-          chain = target.get_callbacks name
-          yield target, chain.dup
+          __update_callbacks(name) do |target, chain|
+            options[:prepend] ? chain.prepend(*mapped) : chain.append(*mapped)
+            target.set_callbacks name, chain
+          end
         end
-      end
 
-      # Install a callback for the given event.
-      #
-      #   set_callback :save, :before, :before_method
-      #   set_callback :save, :after,  :after_method, if: :condition
-      #   set_callback :save, :around, ->(r, block) { stuff; result = block.call; stuff }
-      #
-      # The second argument indicates whether the callback is to be run +:before+,
-      # +:after+, or +:around+ the event. If omitted, +:before+ is assumed. This
-      # means the first example above can also be written as:
-      #
-      #   set_callback :save, :before_method
-      #
-      # The callback can be specified as a symbol naming an instance method; as a
-      # proc, lambda, or block; as a string to be instance evaluated(deprecated); or as an
-      # object that responds to a certain method determined by the <tt>:scope</tt>
-      # argument to +define_callbacks+.
-      #
-      # If a proc, lambda, or block is given, its body is evaluated in the context
-      # of the current object. It can also optionally accept the current object as
-      # an argument.
-      #
-      # Before and around callbacks are called in the order that they are set;
-      # after callbacks are called in the reverse order.
-      #
-      # Around callbacks can access the return value from the event, if it
-      # wasn't halted, from the +yield+ call.
-      #
-      # ===== Options
-      #
-      # * <tt>:if</tt> - A symbol, a string or an array of symbols and strings,
-      #   each naming an instance method or a proc; the callback will be called
-      #   only when they all return a true value.
-      # * <tt>:unless</tt> - A symbol, a string or an array of symbols and
-      #   strings, each naming an instance method or a proc; the callback will
-      #   be called only when they all return a false value.
-      # * <tt>:prepend</tt> - If +true+, the callback will be prepended to the
-      #   existing chain rather than appended.
-      def set_callback(name, *filter_list, &block)
-        type, filters, options = normalize_callback_params(filter_list, block)
-        self_chain = get_callbacks name
-        mapped = filters.map do |filter|
-          Callback.build(self_chain, filter, type, options)
-        end
-
-        __update_callbacks(name) do |target, chain|
-          options[:prepend] ? chain.prepend(*mapped) : chain.append(*mapped)
-          target.set_callbacks name, chain
-        end
-      end
+        # Skip a previously set callback. Like +set_callback+, <tt>:if</tt> or
+        # <tt>:unless</tt> options may be passed in order to control when the
+        # callback is skipped.
+        #
+        #   class Writer < Person
+        #      skip_callback :validate, :before, :check_membership, if: -> { age > 18 }
+        #   end
+        #
+        # An <tt>ArgumentError</tt> will be raised if the callback has not
+        # already been set (unless the <tt>:raise</tt> option is set to <tt>false</tt>).
+        def skip_callback(name, *filter_list, &block)
+          type, filters, options = normalize_callback_params(filter_list, block)
+
+          options[:raise] = true unless options.key?(:raise)
+
+          __update_callbacks(name) do |target, chain|
+            filters.each do |filter|
+              callback = chain.find { |c| c.matches?(type, filter) }
+
+              if !callback && options[:raise]
+                raise ArgumentError, "#{type.to_s.capitalize} #{name} callback #{filter.inspect} has not been defined"
+              end
 
-      # Skip a previously set callback. Like +set_callback+, <tt>:if</tt> or
-      # <tt>:unless</tt> options may be passed in order to control when the
-      # callback is skipped.
-      #
-      #   class Writer < Person
-      #      skip_callback :validate, :before, :check_membership, if: -> { self.age > 18 }
-      #   end
-      #
-      # An <tt>ArgumentError</tt> will be raised if the callback has not
-      # already been set (unless the <tt>:raise</tt> option is set to <tt>false</tt>).
-      def skip_callback(name, *filter_list, &block)
-        type, filters, options = normalize_callback_params(filter_list, block)
-        options[:raise] = true unless options.key?(:raise)
-
-        __update_callbacks(name) do |target, chain|
-          filters.each do |filter|
-            callback = chain.find {|c| c.matches?(type, filter) }
-
-            if !callback && options[:raise]
-              raise ArgumentError, "#{type.to_s.capitalize} #{name} callback #{filter.inspect} has not been defined"
-            end
+              if callback && (options.key?(:if) || options.key?(:unless))
+                new_callback = callback.merge_conditional_options(chain, if_option: options[:if], unless_option: options[:unless])
+                chain.insert(chain.index(callback), new_callback)
+              end
 
-            if callback && (options.key?(:if) || options.key?(:unless))
-              new_callback = callback.merge_conditional_options(chain, if_option: options[:if], unless_option: options[:unless])
-              chain.insert(chain.index(callback), new_callback)
+              chain.delete(callback)
             end
-
-            chain.delete(callback)
+            target.set_callbacks name, chain
           end
-          target.set_callbacks name, chain
         end
-      end
 
-      # Remove all set callbacks for the given event.
-      def reset_callbacks(name)
-        callbacks = get_callbacks name
+        # Remove all set callbacks for the given event.
+        def reset_callbacks(name)
+          callbacks = get_callbacks name
 
-        ActiveSupport::DescendantsTracker.descendants(self).each do |target|
-          chain = target.get_callbacks(name).dup
-          callbacks.each { |c| chain.delete(c) }
-          target.set_callbacks name, chain
-        end
-
-        self.set_callbacks name, callbacks.dup.clear
-      end
+          ActiveSupport::DescendantsTracker.descendants(self).each do |target|
+            chain = target.get_callbacks(name).dup
+            callbacks.each { |c| chain.delete(c) }
+            target.set_callbacks name, chain
+          end
 
-      # Define sets of events in the object life cycle that support callbacks.
-      #
-      #   define_callbacks :validate
-      #   define_callbacks :initialize, :save, :destroy
-      #
-      # ===== Options
-      #
-      # * <tt>:terminator</tt> - Determines when a before filter will halt the
-      #   callback chain, preventing following before and around callbacks from
-      #   being called and the event from being triggered.
-      #   This should be a lambda to be executed.
-      #   The current object and the result lambda of the callback will be provided
-      #   to the terminator lambda.
-      #
-      #     define_callbacks :validate, terminator: ->(target, result_lambda) { result_lambda.call == false }
-      #
-      #   In this example, if any before validate callbacks returns +false+,
-      #   any successive before and around callback is not executed.
-      #
-      #   The default terminator halts the chain when a callback throws +:abort+.
-      #
-      # * <tt>:skip_after_callbacks_if_terminated</tt> - Determines if after
-      #   callbacks should be terminated by the <tt>:terminator</tt> option. By
-      #   default after callbacks are executed no matter if callback chain was
-      #   terminated or not. This option makes sense only when <tt>:terminator</tt>
-      #   option is specified.
-      #
-      # * <tt>:scope</tt> - Indicates which methods should be executed when an
-      #   object is used as a callback.
-      #
-      #     class Audit
-      #       def before(caller)
-      #         puts 'Audit: before is called'
-      #       end
-      #
-      #       def before_save(caller)
-      #         puts 'Audit: before_save is called'
-      #       end
-      #     end
-      #
-      #     class Account
-      #       include ActiveSupport::Callbacks
-      #
-      #       define_callbacks :save
-      #       set_callback :save, :before, Audit.new
-      #
-      #       def save
-      #         run_callbacks :save do
-      #           puts 'save in main'
-      #         end
-      #       end
-      #     end
-      #
-      #   In the above case whenever you save an account the method
-      #   <tt>Audit#before</tt> will be called. On the other hand
-      #
-      #     define_callbacks :save, scope: [:kind, :name]
-      #
-      #   would trigger <tt>Audit#before_save</tt> instead. That's constructed
-      #   by calling <tt>#{kind}_#{name}</tt> on the given instance. In this
-      #   case "kind" is "before" and "name" is "save". In this context +:kind+
-      #   and +:name+ have special meanings: +:kind+ refers to the kind of
-      #   callback (before/after/around) and +:name+ refers to the method on
-      #   which callbacks are being defined.
-      #
-      #   A declaration like
-      #
-      #     define_callbacks :save, scope: [:name]
-      #
-      #   would call <tt>Audit#save</tt>.
-      #
-      # ===== Notes
-      #
-      # +names+ passed to `define_callbacks` must not end with
-      # `!`, `?` or `=`.
-      #
-      # Calling `define_callbacks` multiple times with the same +names+ will
-      # overwrite previous callbacks registered with `set_callback`.
-      def define_callbacks(*names)
-        options = names.extract_options!
-
-        names.each do |name|
-          class_attribute "_#{name}_callbacks", instance_writer: false
-          set_callbacks name, CallbackChain.new(name, options)
-
-          module_eval <<-RUBY, __FILE__, __LINE__ + 1
-            def _run_#{name}_callbacks(&block)
-              __run_callbacks__(_#{name}_callbacks, &block)
-            end
-          RUBY
+          set_callbacks(name, callbacks.dup.clear)
         end
-      end
 
-      protected
+        # Define sets of events in the object life cycle that support callbacks.
+        #
+        #   define_callbacks :validate
+        #   define_callbacks :initialize, :save, :destroy
+        #
+        # ===== Options
+        #
+        # * <tt>:terminator</tt> - Determines when a before filter will halt the
+        #   callback chain, preventing following before and around callbacks from
+        #   being called and the event from being triggered.
+        #   This should be a lambda to be executed.
+        #   The current object and the result lambda of the callback will be provided
+        #   to the terminator lambda.
+        #
+        #     define_callbacks :validate, terminator: ->(target, result_lambda) { result_lambda.call == false }
+        #
+        #   In this example, if any before validate callbacks returns +false+,
+        #   any successive before and around callback is not executed.
+        #
+        #   The default terminator halts the chain when a callback throws +:abort+.
+        #
+        # * <tt>:skip_after_callbacks_if_terminated</tt> - Determines if after
+        #   callbacks should be terminated by the <tt>:terminator</tt> option. By
+        #   default after callbacks are executed no matter if callback chain was
+        #   terminated or not. This option makes sense only when <tt>:terminator</tt>
+        #   option is specified.
+        #
+        # * <tt>:scope</tt> - Indicates which methods should be executed when an
+        #   object is used as a callback.
+        #
+        #     class Audit
+        #       def before(caller)
+        #         puts 'Audit: before is called'
+        #       end
+        #
+        #       def before_save(caller)
+        #         puts 'Audit: before_save is called'
+        #       end
+        #     end
+        #
+        #     class Account
+        #       include ActiveSupport::Callbacks
+        #
+        #       define_callbacks :save
+        #       set_callback :save, :before, Audit.new
+        #
+        #       def save
+        #         run_callbacks :save do
+        #           puts 'save in main'
+        #         end
+        #       end
+        #     end
+        #
+        #   In the above case whenever you save an account the method
+        #   <tt>Audit#before</tt> will be called. On the other hand
+        #
+        #     define_callbacks :save, scope: [:kind, :name]
+        #
+        #   would trigger <tt>Audit#before_save</tt> instead. That's constructed
+        #   by calling <tt>#{kind}_#{name}</tt> on the given instance. In this
+        #   case "kind" is "before" and "name" is "save". In this context +:kind+
+        #   and +:name+ have special meanings: +:kind+ refers to the kind of
+        #   callback (before/after/around) and +:name+ refers to the method on
+        #   which callbacks are being defined.
+        #
+        #   A declaration like
+        #
+        #     define_callbacks :save, scope: [:name]
+        #
+        #   would call <tt>Audit#save</tt>.
+        #
+        # ===== Notes
+        #
+        # +names+ passed to +define_callbacks+ must not end with
+        # <tt>!</tt>, <tt>?</tt> or <tt>=</tt>.
+        #
+        # Calling +define_callbacks+ multiple times with the same +names+ will
+        # overwrite previous callbacks registered with +set_callback+.
+        def define_callbacks(*names)
+          options = names.extract_options!
+
+          names.each do |name|
+            name = name.to_sym
+
+            set_callbacks name, CallbackChain.new(name, options)
+
+            module_eval <<-RUBY, __FILE__, __LINE__ + 1
+              def _run_#{name}_callbacks(&block)
+                run_callbacks #{name.inspect}, &block
+              end
 
-      def get_callbacks(name) # :nodoc:
-        send "_#{name}_callbacks"
-      end
+              def self._#{name}_callbacks
+                get_callbacks(#{name.inspect})
+              end
 
-      def set_callbacks(name, callbacks) # :nodoc:
-        send "_#{name}_callbacks=", callbacks
-      end
+              def self._#{name}_callbacks=(value)
+                set_callbacks(#{name.inspect}, value)
+              end
 
-      def deprecated_false_terminator # :nodoc:
-        Proc.new do |target, result_lambda|
-          terminate = true
-          catch(:abort) do
-            result = result_lambda.call if result_lambda.is_a?(Proc)
-            if Callbacks.halt_and_display_warning_on_return_false && result == false
-              display_deprecation_warning_for_false_terminator
-            else
-              terminate = false
-            end
+              def _#{name}_callbacks
+                __callbacks[#{name.inspect}]
+              end
+            RUBY
           end
-          terminate
         end
-      end
 
-      private
+        protected
+
+          def get_callbacks(name) # :nodoc:
+            __callbacks[name.to_sym]
+          end
 
-      def display_deprecation_warning_for_false_terminator
-        ActiveSupport::Deprecation.warn(<<-MSG.squish)
-          Returning `false` in Active Record and Active Model callbacks will not implicitly halt a callback chain in Rails 5.1.
-          To explicitly halt the callback chain, please use `throw :abort` instead.
-        MSG
+          def set_callbacks(name, callbacks) # :nodoc:
+            self.__callbacks = __callbacks.merge(name.to_sym => callbacks)
+          end
       end
-    end
   end
 end
diff --git a/activesupport/lib/active_support/concern.rb b/activesupport/lib/active_support/concern.rb
index 0403eb70ca..b0a0d845e5 100644
--- a/activesupport/lib/active_support/concern.rb
+++ b/activesupport/lib/active_support/concern.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActiveSupport
   # A typical module looks like this:
   #
@@ -111,7 +113,7 @@ module ActiveSupport
     def append_features(base)
       if base.instance_variable_defined?(:@_dependencies)
         base.instance_variable_get(:@_dependencies) << self
-        return false
+        false
       else
         return false if base < self
         @_dependencies.each { |dep| base.include(dep) }
diff --git a/activesupport/lib/active_support/concurrency/latch.rb b/activesupport/lib/active_support/concurrency/latch.rb
deleted file mode 100644
index 4abe5ece6f..0000000000
--- a/activesupport/lib/active_support/concurrency/latch.rb
+++ /dev/null
@@ -1,19 +0,0 @@
-require 'concurrent/atomic/count_down_latch'
-
-module ActiveSupport
-  module Concurrency
-    class Latch < Concurrent::CountDownLatch
-
-      def initialize(count = 1)
-        ActiveSupport::Deprecation.warn("ActiveSupport::Concurrency::Latch is deprecated. Please use Concurrent::CountDownLatch instead.")
-        super(count)
-      end
-
-      alias_method :release, :count_down
-
-      def await
-        wait(nil)
-      end
-    end
-  end
-end
diff --git a/activesupport/lib/active_support/concurrency/load_interlock_aware_monitor.rb b/activesupport/lib/active_support/concurrency/load_interlock_aware_monitor.rb
new file mode 100644
index 0000000000..a8455c0048
--- /dev/null
+++ b/activesupport/lib/active_support/concurrency/load_interlock_aware_monitor.rb
@@ -0,0 +1,17 @@
+# frozen_string_literal: true
+
+require "monitor"
+
+module ActiveSupport
+  module Concurrency
+    # A monitor that will permit dependency loading while blocked waiting for
+    # the lock.
+    class LoadInterlockAwareMonitor < Monitor
+      # Enters an exclusive section, but allows dependency loading while blocked
+      def mon_enter
+        mon_try_enter ||
+          ActiveSupport::Dependencies.interlock.permit_concurrent_loads { super }
+      end
+    end
+  end
+end
diff --git a/activesupport/lib/active_support/concurrency/share_lock.rb b/activesupport/lib/active_support/concurrency/share_lock.rb
index 89e63aefd4..f18ccf1c88 100644
--- a/activesupport/lib/active_support/concurrency/share_lock.rb
+++ b/activesupport/lib/active_support/concurrency/share_lock.rb
@@ -1,5 +1,7 @@
-require 'thread'
-require 'monitor'
+# frozen_string_literal: true
+
+require "thread"
+require "monitor"
 
 module ActiveSupport
   module Concurrency
@@ -13,6 +15,37 @@ module ActiveSupport
       # we need exclusive locks to be reentrant, and we need to be able
       # to upgrade share locks to exclusive.
 
+      def raw_state # :nodoc:
+        synchronize do
+          threads = @sleeping.keys | @sharing.keys | @waiting.keys
+          threads |= [@exclusive_thread] if @exclusive_thread
+
+          data = {}
+
+          threads.each do |thread|
+            purpose, compatible = @waiting[thread]
+
+            data[thread] = {
+              thread: thread,
+              sharing: @sharing[thread],
+              exclusive: @exclusive_thread == thread,
+              purpose: purpose,
+              compatible: compatible,
+              waiting: !!@waiting[thread],
+              sleeper: @sleeping[thread],
+            }
+          end
+
+          # NB: Yields while holding our *internal* synchronize lock,
+          # which is supposed to be used only for a few instructions at
+          # a time. This allows the caller to inspect additional state
+          # without things changing out from underneath, but would have
+          # disastrous effects upon normal operation. Fortunately, this
+          # method is only intended to be called when things have
+          # already gone wrong.
+          yield data
+        end
+      end
 
       def initialize
         super()
@@ -21,6 +54,7 @@ module ActiveSupport
 
         @sharing = Hash.new(0)
         @waiting = {}
+        @sleeping = {}
         @exclusive_thread = nil
         @exclusive_depth = 0
       end
@@ -46,7 +80,7 @@ module ActiveSupport
               return false if no_wait
 
               yield_shares(purpose: purpose, compatible: compatible, block_share: true) do
-                @cv.wait_while { busy_for_exclusive?(purpose) }
+                wait_for(:start_exclusive) { busy_for_exclusive?(purpose) }
               end
             end
             @exclusive_thread = Thread.current
@@ -69,7 +103,7 @@ module ActiveSupport
 
             if eligible_waiters?(compatible)
               yield_shares(compatible: compatible, block_share: true) do
-                @cv.wait_while { @exclusive_thread || eligible_waiters?(compatible) }
+                wait_for(:stop_exclusive) { @exclusive_thread || eligible_waiters?(compatible) }
               end
             end
             @cv.broadcast
@@ -84,11 +118,11 @@ module ActiveSupport
           elsif @waiting[Thread.current]
             # We're nested inside a +yield_shares+ call: we'll resume as
             # soon as there isn't an exclusive lock in our way
-            @cv.wait_while { @exclusive_thread }
+            wait_for(:start_sharing) { @exclusive_thread }
           else
             # This is an initial / outermost share call: any outstanding
             # requests for an exclusive lock get to go first
-            @cv.wait_while { busy_for_sharing?(false) }
+            wait_for(:start_sharing) { busy_for_sharing?(false) }
           end
           @sharing[Thread.current] += 1
         end
@@ -153,7 +187,7 @@ module ActiveSupport
           yield
         ensure
           synchronize do
-            @cv.wait_while { @exclusive_thread && @exclusive_thread != Thread.current }
+            wait_for(:yield_shares) { @exclusive_thread && @exclusive_thread != Thread.current }
 
             if previous_wait
               @waiting[Thread.current] = previous_wait
@@ -167,20 +201,27 @@ module ActiveSupport
 
       private
 
-      # Must be called within synchronize
-      def busy_for_exclusive?(purpose)
-        busy_for_sharing?(purpose) ||
-          @sharing.size > (@sharing[Thread.current] > 0 ? 1 : 0)
-      end
+        # Must be called within synchronize
+        def busy_for_exclusive?(purpose)
+          busy_for_sharing?(purpose) ||
+            @sharing.size > (@sharing[Thread.current] > 0 ? 1 : 0)
+        end
 
-      def busy_for_sharing?(purpose)
-        (@exclusive_thread && @exclusive_thread != Thread.current) ||
-          @waiting.any? { |t, (_, c)| t != Thread.current && !c.include?(purpose) }
-      end
+        def busy_for_sharing?(purpose)
+          (@exclusive_thread && @exclusive_thread != Thread.current) ||
+            @waiting.any? { |t, (_, c)| t != Thread.current && !c.include?(purpose) }
+        end
 
-      def eligible_waiters?(compatible)
-        @waiting.any? { |t, (p, _)| compatible.include?(p) && @waiting.all? { |t2, (_, c2)| t == t2 || c2.include?(p) } }
-      end
+        def eligible_waiters?(compatible)
+          @waiting.any? { |t, (p, _)| compatible.include?(p) && @waiting.all? { |t2, (_, c2)| t == t2 || c2.include?(p) } }
+        end
+
+        def wait_for(method)
+          @sleeping[Thread.current] = method
+          @cv.wait_while { yield }
+        ensure
+          @sleeping.delete Thread.current
+        end
     end
   end
 end
diff --git a/activesupport/lib/active_support/configurable.rb b/activesupport/lib/active_support/configurable.rb
index 8256c325af..4d6f7819bb 100644
--- a/activesupport/lib/active_support/configurable.rb
+++ b/activesupport/lib/active_support/configurable.rb
@@ -1,6 +1,9 @@
-require 'active_support/concern'
-require 'active_support/ordered_options'
-require 'active_support/core_ext/array/extract_options'
+# frozen_string_literal: true
+
+require "active_support/concern"
+require "active_support/ordered_options"
+require "active_support/core_ext/array/extract_options"
+require "active_support/core_ext/regexp"
 
 module ActiveSupport
   # Configurable provides a <tt>config</tt> method to store and retrieve
@@ -107,7 +110,7 @@ module ActiveSupport
         options = names.extract_options!
 
         names.each do |name|
-          raise NameError.new('invalid config attribute name') unless name =~ /\A[_A-Za-z]\w*\z/
+          raise NameError.new("invalid config attribute name") unless /\A[_A-Za-z]\w*\z/.match?(name)
 
           reader, reader_line = "def #{name}; config.#{name}; end", __LINE__
           writer, writer_line = "def #{name}=(value); config.#{name} = value; end", __LINE__
@@ -145,4 +148,3 @@ module ActiveSupport
     end
   end
 end
-
diff --git a/activesupport/lib/active_support/core_ext.rb b/activesupport/lib/active_support/core_ext.rb
index 52706c3d7a..f590605d84 100644
--- a/activesupport/lib/active_support/core_ext.rb
+++ b/activesupport/lib/active_support/core_ext.rb
@@ -1,4 +1,5 @@
-DEPRECATED_FILES = ["#{File.dirname(__FILE__)}/core_ext/struct.rb"]
-(Dir["#{File.dirname(__FILE__)}/core_ext/*.rb"] - DEPRECATED_FILES).each do |path|
+# frozen_string_literal: true
+
+Dir.glob(File.expand_path("core_ext/*.rb", __dir__)).each do |path|
   require path
 end
diff --git a/activesupport/lib/active_support/core_ext/array.rb b/activesupport/lib/active_support/core_ext/array.rb
index 7551551bd7..6d83b76882 100644
--- a/activesupport/lib/active_support/core_ext/array.rb
+++ b/activesupport/lib/active_support/core_ext/array.rb
@@ -1,7 +1,9 @@
-require 'active_support/core_ext/array/wrap'
-require 'active_support/core_ext/array/access'
-require 'active_support/core_ext/array/conversions'
-require 'active_support/core_ext/array/extract_options'
-require 'active_support/core_ext/array/grouping'
-require 'active_support/core_ext/array/prepend_and_append'
-require 'active_support/core_ext/array/inquiry'
+# frozen_string_literal: true
+
+require "active_support/core_ext/array/wrap"
+require "active_support/core_ext/array/access"
+require "active_support/core_ext/array/conversions"
+require "active_support/core_ext/array/extract_options"
+require "active_support/core_ext/array/grouping"
+require "active_support/core_ext/array/prepend_and_append"
+require "active_support/core_ext/array/inquiry"
diff --git a/activesupport/lib/active_support/core_ext/array/access.rb b/activesupport/lib/active_support/core_ext/array/access.rb
index 37d833887a..b7ff7a3907 100644
--- a/activesupport/lib/active_support/core_ext/array/access.rb
+++ b/activesupport/lib/active_support/core_ext/array/access.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Array
   # Returns the tail of the array from +position+.
   #
@@ -31,10 +33,10 @@ class Array
   #
   #   people = ["David", "Rafael", "Aaron", "Todd"]
   #   people.without "Aaron", "Todd"
-  #     => ["David", "Rafael"]
+  #   # => ["David", "Rafael"]
   #
-  # Note: This is an optimization of `Enumerable#without` that uses `Array#-`
-  # instead of `Array#reject` for performance reasons.
+  # Note: This is an optimization of <tt>Enumerable#without</tt> that uses <tt>Array#-</tt>
+  # instead of <tt>Array#reject</tt> for performance reasons.
   def without(*elements)
     self - elements
   end
diff --git a/activesupport/lib/active_support/core_ext/array/conversions.rb b/activesupport/lib/active_support/core_ext/array/conversions.rb
index 8718b7e1e5..ea688ed2ea 100644
--- a/activesupport/lib/active_support/core_ext/array/conversions.rb
+++ b/activesupport/lib/active_support/core_ext/array/conversions.rb
@@ -1,8 +1,10 @@
-require 'active_support/xml_mini'
-require 'active_support/core_ext/hash/keys'
-require 'active_support/core_ext/string/inflections'
-require 'active_support/core_ext/object/to_param'
-require 'active_support/core_ext/object/to_query'
+# frozen_string_literal: true
+
+require "active_support/xml_mini"
+require "active_support/core_ext/hash/keys"
+require "active_support/core_ext/string/inflections"
+require "active_support/core_ext/object/to_param"
+require "active_support/core_ext/object/to_query"
 
 class Array
   # Converts the array to a comma-separated sentence where the last element is
@@ -60,9 +62,9 @@ class Array
     options.assert_valid_keys(:words_connector, :two_words_connector, :last_word_connector, :locale)
 
     default_connectors = {
-      :words_connector     => ', ',
-      :two_words_connector => ' and ',
-      :last_word_connector => ', and '
+      words_connector: ", ",
+      two_words_connector: " and ",
+      last_word_connector: ", and "
     }
     if defined?(I18n)
       i18n_connectors = I18n.translate(:'support.array', locale: options[:locale], default: {})
@@ -72,7 +74,7 @@ class Array
 
     case length
     when 0
-      ''
+      ""
     when 1
       "#{self[0]}"
     when 2
@@ -92,9 +94,9 @@ class Array
     case format
     when :db
       if empty?
-        'null'
+        "null"
       else
-        collect(&:id).join(',')
+        collect(&:id).join(",")
       end
     else
       to_default_s
@@ -179,7 +181,7 @@ class Array
   #   </messages>
   #
   def to_xml(options = {})
-    require 'active_support/builder' unless defined?(Builder)
+    require "active_support/builder" unless defined?(Builder)
 
     options = options.dup
     options[:indent]  ||= 2
@@ -187,9 +189,9 @@ class Array
     options[:root]    ||= \
       if first.class != Hash && all? { |e| e.is_a?(first.class) }
         underscored = ActiveSupport::Inflector.underscore(first.class.name)
-        ActiveSupport::Inflector.pluralize(underscored).tr('/', '_')
+        ActiveSupport::Inflector.pluralize(underscored).tr("/", "_")
       else
-        'objects'
+        "objects"
       end
 
     builder = options[:builder]
@@ -197,7 +199,7 @@ class Array
 
     root = ActiveSupport::XmlMini.rename_key(options[:root].to_s, options)
     children = options.delete(:children) || root.singularize
-    attributes = options[:skip_types] ? {} : { type: 'array' }
+    attributes = options[:skip_types] ? {} : { type: "array" }
 
     if empty?
       builder.tag!(root, attributes)
diff --git a/activesupport/lib/active_support/core_ext/array/extract_options.rb b/activesupport/lib/active_support/core_ext/array/extract_options.rb
index 9008a0df2a..8c7cb2e780 100644
--- a/activesupport/lib/active_support/core_ext/array/extract_options.rb
+++ b/activesupport/lib/active_support/core_ext/array/extract_options.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Hash
   # By default, only instances of Hash itself are extractable.
   # Subclasses of Hash may implement this method and return
diff --git a/activesupport/lib/active_support/core_ext/array/grouping.rb b/activesupport/lib/active_support/core_ext/array/grouping.rb
index ea9d85f6e3..67e760bc4b 100644
--- a/activesupport/lib/active_support/core_ext/array/grouping.rb
+++ b/activesupport/lib/active_support/core_ext/array/grouping.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Array
   # Splits or iterates over the array in groups of size +number+,
   # padding any remaining slots with +fill_with+ unless it is +false+.
@@ -89,7 +91,7 @@ class Array
   #   [1, 2, 3, 4, 5].split(3)              # => [[1, 2], [4, 5]]
   #   (1..10).to_a.split { |i| i % 3 == 0 } # => [[1, 2], [4, 5], [7, 8], [10]]
   def split(value = nil)
-    arr = self.dup
+    arr = dup
     result = []
     if block_given?
       while (idx = arr.index { |i| yield i })
diff --git a/activesupport/lib/active_support/core_ext/array/inquiry.rb b/activesupport/lib/active_support/core_ext/array/inquiry.rb
index e8f44cc378..92c61bf201 100644
--- a/activesupport/lib/active_support/core_ext/array/inquiry.rb
+++ b/activesupport/lib/active_support/core_ext/array/inquiry.rb
@@ -1,4 +1,6 @@
-require 'active_support/array_inquirer'
+# frozen_string_literal: true
+
+require "active_support/array_inquirer"
 
 class Array
   # Wraps the array in an +ArrayInquirer+ object, which gives a friendlier way
diff --git a/activesupport/lib/active_support/core_ext/array/prepend_and_append.rb b/activesupport/lib/active_support/core_ext/array/prepend_and_append.rb
index f8d48b69df..661971d7cd 100644
--- a/activesupport/lib/active_support/core_ext/array/prepend_and_append.rb
+++ b/activesupport/lib/active_support/core_ext/array/prepend_and_append.rb
@@ -1,7 +1,9 @@
+# frozen_string_literal: true
+
 class Array
   # The human way of thinking about adding stuff to the end of a list is with append.
-  alias_method :append,  :<<
+  alias_method :append,  :push unless [].respond_to?(:append)
 
   # The human way of thinking about adding stuff to the beginning of a list is with prepend.
-  alias_method :prepend, :unshift
-end
\ No newline at end of file
+  alias_method :prepend, :unshift unless [].respond_to?(:prepend)
+end
diff --git a/activesupport/lib/active_support/core_ext/array/wrap.rb b/activesupport/lib/active_support/core_ext/array/wrap.rb
index b611d34c27..d62f97edbf 100644
--- a/activesupport/lib/active_support/core_ext/array/wrap.rb
+++ b/activesupport/lib/active_support/core_ext/array/wrap.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Array
   # Wraps its argument in an array unless it is already an array (or array-like).
   #
diff --git a/activesupport/lib/active_support/core_ext/benchmark.rb b/activesupport/lib/active_support/core_ext/benchmark.rb
index eb25b2bc44..641b58c8b8 100644
--- a/activesupport/lib/active_support/core_ext/benchmark.rb
+++ b/activesupport/lib/active_support/core_ext/benchmark.rb
@@ -1,4 +1,6 @@
-require 'benchmark'
+# frozen_string_literal: true
+
+require "benchmark"
 
 class << Benchmark
   # Benchmark realtime in milliseconds.
diff --git a/activesupport/lib/active_support/core_ext/big_decimal.rb b/activesupport/lib/active_support/core_ext/big_decimal.rb
index 8143113cfa..9e6a9d6331 100644
--- a/activesupport/lib/active_support/core_ext/big_decimal.rb
+++ b/activesupport/lib/active_support/core_ext/big_decimal.rb
@@ -1 +1,3 @@
-require 'active_support/core_ext/big_decimal/conversions'
+# frozen_string_literal: true
+
+require "active_support/core_ext/big_decimal/conversions"
diff --git a/activesupport/lib/active_support/core_ext/big_decimal/conversions.rb b/activesupport/lib/active_support/core_ext/big_decimal/conversions.rb
index 074e2eabf8..52bd229416 100644
--- a/activesupport/lib/active_support/core_ext/big_decimal/conversions.rb
+++ b/activesupport/lib/active_support/core_ext/big_decimal/conversions.rb
@@ -1,9 +1,11 @@
-require 'bigdecimal'
-require 'bigdecimal/util'
+# frozen_string_literal: true
+
+require "bigdecimal"
+require "bigdecimal/util"
 
 module ActiveSupport
   module BigDecimalWithDefaultFormat #:nodoc:
-    def to_s(format = 'F')
+    def to_s(format = "F")
       super(format)
     end
   end
diff --git a/activesupport/lib/active_support/core_ext/class.rb b/activesupport/lib/active_support/core_ext/class.rb
index ef903d59b5..1c110fd07b 100644
--- a/activesupport/lib/active_support/core_ext/class.rb
+++ b/activesupport/lib/active_support/core_ext/class.rb
@@ -1,2 +1,4 @@
-require 'active_support/core_ext/class/attribute'
-require 'active_support/core_ext/class/subclasses'
+# frozen_string_literal: true
+
+require "active_support/core_ext/class/attribute"
+require "active_support/core_ext/class/subclasses"
diff --git a/activesupport/lib/active_support/core_ext/class/attribute.rb b/activesupport/lib/active_support/core_ext/class/attribute.rb
index 802d988af2..7928efb871 100644
--- a/activesupport/lib/active_support/core_ext/class/attribute.rb
+++ b/activesupport/lib/active_support/core_ext/class/attribute.rb
@@ -1,11 +1,23 @@
-require 'active_support/core_ext/kernel/singleton_class'
-require 'active_support/core_ext/module/remove_method'
-require 'active_support/core_ext/array/extract_options'
+# frozen_string_literal: true
+
+require "active_support/core_ext/kernel/singleton_class"
+require "active_support/core_ext/module/redefine_method"
+require "active_support/core_ext/array/extract_options"
 
 class Class
   # Declare a class-level attribute whose value is inheritable by subclasses.
   # Subclasses can change their own value and it will not impact parent class.
   #
+  # ==== Options
+  #
+  # * <tt>:instance_reader</tt> - Sets the instance reader method (defaults to true).
+  # * <tt>:instance_writer</tt> - Sets the instance writer method (defaults to true).
+  # * <tt>:instance_accessor</tt> - Sets both instance methods (defaults to true).
+  # * <tt>:instance_predicate</tt> - Sets a predicate method (defaults to true).
+  # * <tt>:default</tt> - Sets a default value for the attribute (defaults to nil).
+  #
+  # ==== Examples
+  #
   #   class Base
   #     class_attribute :setting
   #   end
@@ -20,14 +32,14 @@ class Class
   #   Base.setting                # => true
   #
   # In the above case as long as Subclass does not assign a value to setting
-  # by performing <tt>Subclass.setting = _something_ </tt>, <tt>Subclass.setting</tt>
+  # by performing <tt>Subclass.setting = _something_</tt>, <tt>Subclass.setting</tt>
   # would read value assigned to parent class. Once Subclass assigns a value then
   # the value assigned by Subclass would be returned.
   #
   # This matches normal Ruby method inheritance: think of writing an attribute
   # on a subclass as overriding the reader method. However, you need to be aware
   # when using +class_attribute+ with mutable structures as +Array+ or +Hash+.
-  # In such cases, you don't want to do changes in places but use setters:
+  # In such cases, you don't want to do changes in place. Instead use setters:
   #
   #   Base.setting = []
   #   Base.setting                # => []
@@ -68,32 +80,35 @@ class Class
   #   object.setting = false  # => NoMethodError
   #
   # To opt out of both instance methods, pass <tt>instance_accessor: false</tt>.
+  #
+  # To set a default value for the attribute, pass <tt>default:</tt>, like so:
+  #
+  #   class_attribute :settings, default: {}
   def class_attribute(*attrs)
     options = attrs.extract_options!
-    instance_reader = options.fetch(:instance_accessor, true) && options.fetch(:instance_reader, true)
-    instance_writer = options.fetch(:instance_accessor, true) && options.fetch(:instance_writer, true)
+    instance_reader    = options.fetch(:instance_accessor, true) && options.fetch(:instance_reader, true)
+    instance_writer    = options.fetch(:instance_accessor, true) && options.fetch(:instance_writer, true)
     instance_predicate = options.fetch(:instance_predicate, true)
+    default_value      = options.fetch(:default, nil)
 
     attrs.each do |name|
-      remove_possible_singleton_method(name)
+      singleton_class.silence_redefinition_of_method(name)
       define_singleton_method(name) { nil }
 
-      remove_possible_singleton_method("#{name}?")
+      singleton_class.silence_redefinition_of_method("#{name}?")
       define_singleton_method("#{name}?") { !!public_send(name) } if instance_predicate
 
       ivar = "@#{name}"
 
-      remove_possible_singleton_method("#{name}=")
+      singleton_class.silence_redefinition_of_method("#{name}=")
       define_singleton_method("#{name}=") do |val|
         singleton_class.class_eval do
-          remove_possible_method(name)
-          define_method(name) { val }
+          redefine_method(name) { val }
         end
 
         if singleton_class?
           class_eval do
-            remove_possible_method(name)
-            define_method(name) do
+            redefine_method(name) do
               if instance_variable_defined? ivar
                 instance_variable_get ivar
               else
@@ -106,8 +121,7 @@ class Class
       end
 
       if instance_reader
-        remove_possible_method name
-        define_method(name) do
+        redefine_method(name) do
           if instance_variable_defined?(ivar)
             instance_variable_get ivar
           else
@@ -115,13 +129,17 @@ class Class
           end
         end
 
-        remove_possible_method "#{name}?"
-        define_method("#{name}?") { !!public_send(name) } if instance_predicate
+        redefine_method("#{name}?") { !!public_send(name) } if instance_predicate
       end
 
       if instance_writer
-        remove_possible_method "#{name}="
-        attr_writer name
+        redefine_method("#{name}=") do |val|
+          instance_variable_set ivar, val
+        end
+      end
+
+      unless default_value.nil?
+        self.send("#{name}=", default_value)
       end
     end
   end
diff --git a/activesupport/lib/active_support/core_ext/class/attribute_accessors.rb b/activesupport/lib/active_support/core_ext/class/attribute_accessors.rb
index 84d5e95e7a..a77354e153 100644
--- a/activesupport/lib/active_support/core_ext/class/attribute_accessors.rb
+++ b/activesupport/lib/active_support/core_ext/class/attribute_accessors.rb
@@ -1,4 +1,6 @@
+# frozen_string_literal: true
+
 # cattr_* became mattr_* aliases in 7dfbd91b0780fbd6a1dd9bfbc176e10894871d2d,
 # but we keep this around for libraries that directly require it knowing they
 # want cattr_*. No need to deprecate.
-require 'active_support/core_ext/module/attribute_accessors'
+require "active_support/core_ext/module/attribute_accessors"
diff --git a/activesupport/lib/active_support/core_ext/class/subclasses.rb b/activesupport/lib/active_support/core_ext/class/subclasses.rb
index 1d8c33b43e..75e65337b7 100644
--- a/activesupport/lib/active_support/core_ext/class/subclasses.rb
+++ b/activesupport/lib/active_support/core_ext/class/subclasses.rb
@@ -1,20 +1,33 @@
-require 'active_support/core_ext/module/anonymous'
-require 'active_support/core_ext/module/reachable'
+# frozen_string_literal: true
 
 class Class
   begin
     # Test if this Ruby supports each_object against singleton_class
     ObjectSpace.each_object(Numeric.singleton_class) {}
 
-    def descendants # :nodoc:
+    # Returns an array with all classes that are < than its receiver.
+    #
+    #   class C; end
+    #   C.descendants # => []
+    #
+    #   class B < C; end
+    #   C.descendants # => [B]
+    #
+    #   class A < B; end
+    #   C.descendants # => [B, A]
+    #
+    #   class D < C; end
+    #   C.descendants # => [B, A, D]
+    def descendants
       descendants = []
       ObjectSpace.each_object(singleton_class) do |k|
+        next if k.singleton_class?
         descendants.unshift k unless k == self
       end
       descendants
     end
   rescue StandardError # JRuby 9.0.4.0 and earlier
-    def descendants # :nodoc:
+    def descendants
       descendants = []
       ObjectSpace.each_object(Class) do |k|
         descendants.unshift k if k < self
diff --git a/activesupport/lib/active_support/core_ext/date.rb b/activesupport/lib/active_support/core_ext/date.rb
index 7f0f4639a2..cce73f2db2 100644
--- a/activesupport/lib/active_support/core_ext/date.rb
+++ b/activesupport/lib/active_support/core_ext/date.rb
@@ -1,5 +1,7 @@
-require 'active_support/core_ext/date/acts_like'
-require 'active_support/core_ext/date/blank'
-require 'active_support/core_ext/date/calculations'
-require 'active_support/core_ext/date/conversions'
-require 'active_support/core_ext/date/zones'
+# frozen_string_literal: true
+
+require "active_support/core_ext/date/acts_like"
+require "active_support/core_ext/date/blank"
+require "active_support/core_ext/date/calculations"
+require "active_support/core_ext/date/conversions"
+require "active_support/core_ext/date/zones"
diff --git a/activesupport/lib/active_support/core_ext/date/acts_like.rb b/activesupport/lib/active_support/core_ext/date/acts_like.rb
index cd90cee236..c8077f3774 100644
--- a/activesupport/lib/active_support/core_ext/date/acts_like.rb
+++ b/activesupport/lib/active_support/core_ext/date/acts_like.rb
@@ -1,4 +1,6 @@
-require 'active_support/core_ext/object/acts_like'
+# frozen_string_literal: true
+
+require "active_support/core_ext/object/acts_like"
 
 class Date
   # Duck-types as a Date-like class. See Object#acts_like?.
diff --git a/activesupport/lib/active_support/core_ext/date/blank.rb b/activesupport/lib/active_support/core_ext/date/blank.rb
index 71627b6a6f..e6271c79b3 100644
--- a/activesupport/lib/active_support/core_ext/date/blank.rb
+++ b/activesupport/lib/active_support/core_ext/date/blank.rb
@@ -1,4 +1,6 @@
-require 'date'
+# frozen_string_literal: true
+
+require "date"
 
 class Date #:nodoc:
   # No Date is blank:
diff --git a/activesupport/lib/active_support/core_ext/date/calculations.rb b/activesupport/lib/active_support/core_ext/date/calculations.rb
index d589b67bf7..1cd7acb05d 100644
--- a/activesupport/lib/active_support/core_ext/date/calculations.rb
+++ b/activesupport/lib/active_support/core_ext/date/calculations.rb
@@ -1,9 +1,11 @@
-require 'date'
-require 'active_support/duration'
-require 'active_support/core_ext/object/acts_like'
-require 'active_support/core_ext/date/zones'
-require 'active_support/core_ext/time/zones'
-require 'active_support/core_ext/date_and_time/calculations'
+# frozen_string_literal: true
+
+require "date"
+require "active_support/duration"
+require "active_support/core_ext/object/acts_like"
+require "active_support/core_ext/date/zones"
+require "active_support/core_ext/time/zones"
+require "active_support/core_ext/date_and_time/calculations"
 
 class Date
   include DateAndTime::Calculations
@@ -129,11 +131,11 @@ class Date
       options.fetch(:day, day)
     )
   end
-  
+
   # Allow Date to be compared with Time by converting to DateTime and relying on the <=> from there.
   def compare_with_coercion(other)
     if other.is_a?(Time)
-      self.to_datetime <=> other
+      to_datetime <=> other
     else
       compare_without_coercion(other)
     end
diff --git a/activesupport/lib/active_support/core_ext/date/conversions.rb b/activesupport/lib/active_support/core_ext/date/conversions.rb
index 6e3b4a89ce..870119dc7f 100644
--- a/activesupport/lib/active_support/core_ext/date/conversions.rb
+++ b/activesupport/lib/active_support/core_ext/date/conversions.rb
@@ -1,30 +1,24 @@
-require 'date'
-require 'active_support/inflector/methods'
-require 'active_support/core_ext/date/zones'
-require 'active_support/core_ext/module/remove_method'
+# frozen_string_literal: true
+
+require "date"
+require "active_support/inflector/methods"
+require "active_support/core_ext/date/zones"
+require "active_support/core_ext/module/redefine_method"
 
 class Date
   DATE_FORMATS = {
-    :short        => '%d %b',
-    :long         => '%B %d, %Y',
-    :db           => '%Y-%m-%d',
-    :number       => '%Y%m%d',
-    :long_ordinal => lambda { |date|
+    short: "%d %b",
+    long: "%B %d, %Y",
+    db: "%Y-%m-%d",
+    number: "%Y%m%d",
+    long_ordinal: lambda { |date|
       day_format = ActiveSupport::Inflector.ordinalize(date.day)
       date.strftime("%B #{day_format}, %Y") # => "April 25th, 2007"
     },
-    :rfc822       => '%d %b %Y',
-    :iso8601      => lambda { |date| date.iso8601 }
+    rfc822: "%d %b %Y",
+    iso8601: lambda { |date| date.iso8601 }
   }
 
-  # Ruby 1.9 has Date#to_time which converts to localtime only.
-  remove_method :to_time
-
-  # Ruby 1.9 has Date#xmlschema which converts to a string without the time
-  # component. This removal may generate an issue on FreeBSD, that's why we
-  # need to use remove_possible_method here
-  remove_possible_method :xmlschema
-
   # Convert to a formatted string. See DATE_FORMATS for predefined formats.
   #
   # This method is aliased to <tt>to_s</tt>.
@@ -65,11 +59,13 @@ class Date
 
   # Overrides the default inspect method with a human readable one, e.g., "Mon, 21 Feb 2005"
   def readable_inspect
-    strftime('%a, %d %b %Y')
+    strftime("%a, %d %b %Y")
   end
   alias_method :default_inspect, :inspect
   alias_method :inspect, :readable_inspect
 
+  silence_redefinition_of_method :to_time
+
   # Converts a Date instance to a Time, where the time is set to the beginning of the day.
   # The timezone can be either :local or :utc (default :local).
   #
@@ -79,11 +75,16 @@ class Date
   #   date.to_time(:local)           # => 2007-11-10 00:00:00 0800
   #
   #   date.to_time(:utc)             # => 2007-11-10 00:00:00 UTC
+  #
+  # NOTE: The :local timezone is Ruby's *process* timezone, i.e. ENV['TZ'].
+  #       If the *application's* timezone is needed, then use +in_time_zone+ instead.
   def to_time(form = :local)
     raise ArgumentError, "Expected :local or :utc, got #{form.inspect}." unless [:local, :utc].include?(form)
     ::Time.send(form, year, month, day)
   end
 
+  silence_redefinition_of_method :xmlschema
+
   # Returns a string which represents the time in used time zone as DateTime
   # defined by XML Schema:
   #
diff --git a/activesupport/lib/active_support/core_ext/date/zones.rb b/activesupport/lib/active_support/core_ext/date/zones.rb
index d109b430db..2dcf97cff8 100644
--- a/activesupport/lib/active_support/core_ext/date/zones.rb
+++ b/activesupport/lib/active_support/core_ext/date/zones.rb
@@ -1,5 +1,7 @@
-require 'date'
-require 'active_support/core_ext/date_and_time/zones'
+# frozen_string_literal: true
+
+require "date"
+require "active_support/core_ext/date_and_time/zones"
 
 class Date
   include DateAndTime::Zones
diff --git a/activesupport/lib/active_support/core_ext/date_and_time/calculations.rb b/activesupport/lib/active_support/core_ext/date_and_time/calculations.rb
index 6206546672..f6cb1a384c 100644
--- a/activesupport/lib/active_support/core_ext/date_and_time/calculations.rb
+++ b/activesupport/lib/active_support/core_ext/date_and_time/calculations.rb
@@ -1,15 +1,17 @@
-require 'active_support/core_ext/object/try'
+# frozen_string_literal: true
+
+require "active_support/core_ext/object/try"
 
 module DateAndTime
   module Calculations
     DAYS_INTO_WEEK = {
-      :monday    => 0,
-      :tuesday   => 1,
-      :wednesday => 2,
-      :thursday  => 3,
-      :friday    => 4,
-      :saturday  => 5,
-      :sunday    => 6
+      monday: 0,
+      tuesday: 1,
+      wednesday: 2,
+      thursday: 3,
+      friday: 4,
+      saturday: 5,
+      sunday: 6
     }
     WEEKEND_DAYS = [ 6, 0 ]
 
@@ -18,9 +20,9 @@ module DateAndTime
       advance(days: -1)
     end
 
-    # Returns a new date/time representing the previous day.
-    def prev_day
-      advance(days: -1)
+    # Returns a new date/time the specified number of days ago.
+    def prev_day(days = 1)
+      advance(days: -days)
     end
 
     # Returns a new date/time representing tomorrow.
@@ -28,9 +30,9 @@ module DateAndTime
       advance(days: 1)
     end
 
-    # Returns a new date/time representing the next day.
-    def next_day
-      advance(days: 1)
+    # Returns a new date/time the specified number of days in the future.
+    def next_day(days = 1)
+      advance(days: days)
     end
 
     # Returns true if the date/time is today.
@@ -60,42 +62,42 @@ module DateAndTime
 
     # Returns a new date/time the specified number of days ago.
     def days_ago(days)
-      advance(:days => -days)
+      advance(days: -days)
     end
 
     # Returns a new date/time the specified number of days in the future.
     def days_since(days)
-      advance(:days => days)
+      advance(days: days)
     end
 
     # Returns a new date/time the specified number of weeks ago.
     def weeks_ago(weeks)
-      advance(:weeks => -weeks)
+      advance(weeks: -weeks)
     end
 
     # Returns a new date/time the specified number of weeks in the future.
     def weeks_since(weeks)
-      advance(:weeks => weeks)
+      advance(weeks: weeks)
     end
 
     # Returns a new date/time the specified number of months ago.
     def months_ago(months)
-      advance(:months => -months)
+      advance(months: -months)
     end
 
     # Returns a new date/time the specified number of months in the future.
     def months_since(months)
-      advance(:months => months)
+      advance(months: months)
     end
 
     # Returns a new date/time the specified number of years ago.
     def years_ago(years)
-      advance(:years => -years)
+      advance(years: -years)
     end
 
     # Returns a new date/time the specified number of years in the future.
     def years_since(years)
-      advance(:years => years)
+      advance(years: years)
     end
 
     # Returns a new date/time at the start of the month.
@@ -108,7 +110,7 @@ module DateAndTime
     #   now = DateTime.current # => Thu, 18 Jun 2015 15:23:13 +0000
     #   now.beginning_of_month # => Mon, 01 Jun 2015 00:00:00 +0000
     def beginning_of_month
-      first_hour(change(:day => 1))
+      first_hour(change(day: 1))
     end
     alias :at_beginning_of_month :beginning_of_month
 
@@ -123,7 +125,7 @@ module DateAndTime
     #   now.beginning_of_quarter # => Wed, 01 Jul 2015 00:00:00 +0000
     def beginning_of_quarter
       first_quarter_month = [10, 7, 4, 1].detect { |m| m <= month }
-      beginning_of_month.change(:month => first_quarter_month)
+      beginning_of_month.change(month: first_quarter_month)
     end
     alias :at_beginning_of_quarter :beginning_of_quarter
 
@@ -138,7 +140,7 @@ module DateAndTime
     #   now.end_of_quarter # => Wed, 30 Sep 2015 23:59:59 +0000
     def end_of_quarter
       last_quarter_month = [3, 6, 9, 12].detect { |m| m >= month }
-      beginning_of_month.change(:month => last_quarter_month).end_of_month
+      beginning_of_month.change(month: last_quarter_month).end_of_month
     end
     alias :at_end_of_quarter :end_of_quarter
 
@@ -152,7 +154,7 @@ module DateAndTime
     #   now = DateTime.current # => Fri, 10 Jul 2015 18:41:29 +0000
     #   now.beginning_of_year # => Thu, 01 Jan 2015 00:00:00 +0000
     def beginning_of_year
-      change(:month => 1).beginning_of_month
+      change(month: 1).beginning_of_month
     end
     alias :at_beginning_of_year :beginning_of_year
 
@@ -186,9 +188,9 @@ module DateAndTime
       end
     end
 
-    # Short-hand for months_since(1).
-    def next_month
-      months_since(1)
+    # Returns a new date/time the specified number of months in the future.
+    def next_month(months = 1)
+      advance(months: months)
     end
 
     # Short-hand for months_since(3)
@@ -196,9 +198,9 @@ module DateAndTime
       months_since(3)
     end
 
-    # Short-hand for years_since(1).
-    def next_year
-      years_since(1)
+    # Returns a new date/time the specified number of years in the future.
+    def next_year(years = 1)
+      advance(years: years)
     end
 
     # Returns a new date/time representing the given day in the previous week.
@@ -221,11 +223,15 @@ module DateAndTime
     end
     alias_method :last_weekday, :prev_weekday
 
+    # Returns a new date/time the specified number of months ago.
+    def prev_month(months = 1)
+      advance(months: -months)
+    end
+
     # Short-hand for months_ago(1).
-    def prev_month
+    def last_month
       months_ago(1)
     end
-    alias_method :last_month, :prev_month
 
     # Short-hand for months_ago(3).
     def prev_quarter
@@ -233,11 +239,15 @@ module DateAndTime
     end
     alias_method :last_quarter, :prev_quarter
 
+    # Returns a new date/time the specified number of years ago.
+    def prev_year(years = 1)
+      advance(years: -years)
+    end
+
     # Short-hand for years_ago(1).
-    def prev_year
+    def last_year
       years_ago(1)
     end
-    alias_method :last_year, :prev_year
 
     # Returns the number of days to the start of the week on the given day.
     # Week is assumed to start on +start_day+, default is
@@ -290,7 +300,7 @@ module DateAndTime
     # Returns a new date/time representing the end of the year.
     # DateTime objects will have a time set to 23:59:59.
     def end_of_year
-      change(:month => 12).end_of_month
+      change(month: 12).end_of_month
     end
     alias :at_end_of_year :end_of_year
 
@@ -300,7 +310,7 @@ module DateAndTime
     end
 
     # Returns a Range representing the whole week of the current date/time.
-    # Week starts on start_day, default is <tt>Date.week_start</tt> or <tt>config.week_start</tt> when set.
+    # Week starts on start_day, default is <tt>Date.beginning_of_week</tt> or <tt>config.beginning_of_week</tt> when set.
     def all_week(start_day = Date.beginning_of_week)
       beginning_of_week(start_day)..end_of_week(start_day)
     end
@@ -320,6 +330,30 @@ module DateAndTime
       beginning_of_year..end_of_year
     end
 
+    # Returns a new date/time representing the next occurrence of the specified day of week.
+    #
+    #   today = Date.today               # => Thu, 14 Dec 2017
+    #   today.next_occurring(:monday)    # => Mon, 18 Dec 2017
+    #   today.next_occurring(:thursday)  # => Thu, 21 Dec 2017
+    def next_occurring(day_of_week)
+      current_day_number = wday != 0 ? wday - 1 : 6
+      from_now = DAYS_INTO_WEEK.fetch(day_of_week) - current_day_number
+      from_now += 7 unless from_now > 0
+      advance(days: from_now)
+    end
+
+    # Returns a new date/time representing the previous occurrence of the specified day of week.
+    #
+    #   today = Date.today               # => Thu, 14 Dec 2017
+    #   today.prev_occurring(:monday)    # => Mon, 11 Dec 2017
+    #   today.prev_occurring(:thursday)  # => Thu, 07 Dec 2017
+    def prev_occurring(day_of_week)
+      current_day_number = wday != 0 ? wday - 1 : 6
+      ago = current_day_number - DAYS_INTO_WEEK.fetch(day_of_week)
+      ago += 7 unless ago > 0
+      advance(days: -ago)
+    end
+
     private
       def first_hour(date_or_time)
         date_or_time.acts_like?(:time) ? date_or_time.beginning_of_day : date_or_time
@@ -334,7 +368,7 @@ module DateAndTime
       end
 
       def copy_time_to(other)
-        other.change(hour: hour, min: min, sec: sec, usec: try(:usec))
+        other.change(hour: hour, min: min, sec: sec, nsec: try(:nsec))
       end
   end
 end
diff --git a/activesupport/lib/active_support/core_ext/date_and_time/compatibility.rb b/activesupport/lib/active_support/core_ext/date_and_time/compatibility.rb
index 19e596a144..d33c36ef73 100644
--- a/activesupport/lib/active_support/core_ext/date_and_time/compatibility.rb
+++ b/activesupport/lib/active_support/core_ext/date_and_time/compatibility.rb
@@ -1,4 +1,6 @@
-require 'active_support/core_ext/module/attribute_accessors'
+# frozen_string_literal: true
+
+require "active_support/core_ext/module/attribute_accessors"
 
 module DateAndTime
   module Compatibility
@@ -9,10 +11,6 @@ module DateAndTime
     # of the receiver. For backwards compatibility we're overriding
     # this behavior, but new apps will have an initializer that sets
     # this to true, because the new behavior is preferred.
-    mattr_accessor(:preserve_timezone, instance_writer: false) { false }
-
-    def to_time
-      preserve_timezone ? getlocal(utc_offset) : getlocal
-    end
+    mattr_accessor :preserve_timezone, instance_writer: false, default: false
   end
 end
diff --git a/activesupport/lib/active_support/core_ext/date_and_time/zones.rb b/activesupport/lib/active_support/core_ext/date_and_time/zones.rb
index e2432c8f8a..894fd9b76d 100644
--- a/activesupport/lib/active_support/core_ext/date_and_time/zones.rb
+++ b/activesupport/lib/active_support/core_ext/date_and_time/zones.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module DateAndTime
   module Zones
     # Returns the simultaneous time in <tt>Time.zone</tt> if a zone is given or
@@ -22,19 +24,18 @@ module DateAndTime
       if time_zone
         time_with_zone(time, time_zone)
       else
-        time || self.to_time
+        time || to_time
       end
     end
 
     private
 
-    def time_with_zone(time, zone)
-      if time
-        ActiveSupport::TimeWithZone.new(time.utc? ? time : time.getutc, zone)
-      else
-        ActiveSupport::TimeWithZone.new(nil, zone, to_time(:utc))
+      def time_with_zone(time, zone)
+        if time
+          ActiveSupport::TimeWithZone.new(time.utc? ? time : time.getutc, zone)
+        else
+          ActiveSupport::TimeWithZone.new(nil, zone, to_time(:utc))
+        end
       end
-    end
   end
 end
-
diff --git a/activesupport/lib/active_support/core_ext/date_time.rb b/activesupport/lib/active_support/core_ext/date_time.rb
index 86177488c0..790dbeec1b 100644
--- a/activesupport/lib/active_support/core_ext/date_time.rb
+++ b/activesupport/lib/active_support/core_ext/date_time.rb
@@ -1,5 +1,7 @@
-require 'active_support/core_ext/date_time/acts_like'
-require 'active_support/core_ext/date_time/blank'
-require 'active_support/core_ext/date_time/calculations'
-require 'active_support/core_ext/date_time/compatibility'
-require 'active_support/core_ext/date_time/conversions'
+# frozen_string_literal: true
+
+require "active_support/core_ext/date_time/acts_like"
+require "active_support/core_ext/date_time/blank"
+require "active_support/core_ext/date_time/calculations"
+require "active_support/core_ext/date_time/compatibility"
+require "active_support/core_ext/date_time/conversions"
diff --git a/activesupport/lib/active_support/core_ext/date_time/acts_like.rb b/activesupport/lib/active_support/core_ext/date_time/acts_like.rb
index 8fbbe0d3e9..5dccdfe219 100644
--- a/activesupport/lib/active_support/core_ext/date_time/acts_like.rb
+++ b/activesupport/lib/active_support/core_ext/date_time/acts_like.rb
@@ -1,5 +1,7 @@
-require 'date'
-require 'active_support/core_ext/object/acts_like'
+# frozen_string_literal: true
+
+require "date"
+require "active_support/core_ext/object/acts_like"
 
 class DateTime
   # Duck-types as a Date-like class. See Object#acts_like?.
diff --git a/activesupport/lib/active_support/core_ext/date_time/blank.rb b/activesupport/lib/active_support/core_ext/date_time/blank.rb
index 56981b75fb..a52c8bc150 100644
--- a/activesupport/lib/active_support/core_ext/date_time/blank.rb
+++ b/activesupport/lib/active_support/core_ext/date_time/blank.rb
@@ -1,4 +1,6 @@
-require 'date'
+# frozen_string_literal: true
+
+require "date"
 
 class DateTime #:nodoc:
   # No DateTime is ever blank:
diff --git a/activesupport/lib/active_support/core_ext/date_time/calculations.rb b/activesupport/lib/active_support/core_ext/date_time/calculations.rb
index 9e89a33491..e61b23f842 100644
--- a/activesupport/lib/active_support/core_ext/date_time/calculations.rb
+++ b/activesupport/lib/active_support/core_ext/date_time/calculations.rb
@@ -1,4 +1,6 @@
-require 'date'
+# frozen_string_literal: true
+
+require "date"
 
 class DateTime
   class << self
@@ -47,13 +49,23 @@ class DateTime
   #   DateTime.new(2012, 8, 29, 22, 35, 0).change(year: 1981, day: 1)  # => DateTime.new(1981, 8, 1, 22, 35, 0)
   #   DateTime.new(2012, 8, 29, 22, 35, 0).change(year: 1981, hour: 0) # => DateTime.new(1981, 8, 29, 0, 0, 0)
   def change(options)
+    if new_nsec = options[:nsec]
+      raise ArgumentError, "Can't change both :nsec and :usec at the same time: #{options.inspect}" if options[:usec]
+      new_fraction = Rational(new_nsec, 1000000000)
+    else
+      new_usec = options.fetch(:usec, (options[:hour] || options[:min] || options[:sec]) ? 0 : Rational(nsec, 1000))
+      new_fraction = Rational(new_usec, 1000000)
+    end
+
+    raise ArgumentError, "argument out of range" if new_fraction >= 1
+
     ::DateTime.civil(
       options.fetch(:year, year),
       options.fetch(:month, month),
       options.fetch(:day, day),
       options.fetch(:hour, hour),
       options.fetch(:min, options[:hour] ? 0 : min),
-      options.fetch(:sec, (options[:hour] || options[:min]) ? 0 : sec + sec_fraction),
+      options.fetch(:sec, (options[:hour] || options[:min]) ? 0 : sec) + new_fraction,
       options.fetch(:offset, offset),
       options.fetch(:start, start)
     )
@@ -75,7 +87,7 @@ class DateTime
     end
 
     d = to_date.advance(options)
-    datetime_advanced_by_date = change(:year => d.year, :month => d.month, :day => d.day)
+    datetime_advanced_by_date = change(year: d.year, month: d.month, day: d.day)
     seconds_to_advance = \
       options.fetch(:seconds, 0) +
       options.fetch(:minutes, 0) * 60 +
@@ -104,7 +116,7 @@ class DateTime
 
   # Returns a new DateTime representing the start of the day (0:00).
   def beginning_of_day
-    change(:hour => 0)
+    change(hour: 0)
   end
   alias :midnight :beginning_of_day
   alias :at_midnight :beginning_of_day
@@ -112,7 +124,7 @@ class DateTime
 
   # Returns a new DateTime representing the middle of the day (12:00)
   def middle_of_day
-    change(:hour => 12)
+    change(hour: 12)
   end
   alias :midday :middle_of_day
   alias :noon :middle_of_day
@@ -122,31 +134,31 @@ class DateTime
 
   # Returns a new DateTime representing the end of the day (23:59:59).
   def end_of_day
-    change(:hour => 23, :min => 59, :sec => 59)
+    change(hour: 23, min: 59, sec: 59, usec: Rational(999999999, 1000))
   end
   alias :at_end_of_day :end_of_day
 
   # Returns a new DateTime representing the start of the hour (hh:00:00).
   def beginning_of_hour
-    change(:min => 0)
+    change(min: 0)
   end
   alias :at_beginning_of_hour :beginning_of_hour
 
   # Returns a new DateTime representing the end of the hour (hh:59:59).
   def end_of_hour
-    change(:min => 59, :sec => 59)
+    change(min: 59, sec: 59, usec: Rational(999999999, 1000))
   end
   alias :at_end_of_hour :end_of_hour
 
   # Returns a new DateTime representing the start of the minute (hh:mm:00).
   def beginning_of_minute
-    change(:sec => 0)
+    change(sec: 0)
   end
   alias :at_beginning_of_minute :beginning_of_minute
 
   # Returns a new DateTime representing the end of the minute (hh:mm:59).
   def end_of_minute
-    change(:sec => 59)
+    change(sec: 59, usec: Rational(999999999, 1000))
   end
   alias :at_end_of_minute :end_of_minute
 
diff --git a/activesupport/lib/active_support/core_ext/date_time/compatibility.rb b/activesupport/lib/active_support/core_ext/date_time/compatibility.rb
index 03e4a2adfa..2d6b49722d 100644
--- a/activesupport/lib/active_support/core_ext/date_time/compatibility.rb
+++ b/activesupport/lib/active_support/core_ext/date_time/compatibility.rb
@@ -1,5 +1,18 @@
-require 'active_support/core_ext/date_and_time/compatibility'
+# frozen_string_literal: true
+
+require "active_support/core_ext/date_and_time/compatibility"
+require "active_support/core_ext/module/redefine_method"
 
 class DateTime
-  prepend DateAndTime::Compatibility
+  include DateAndTime::Compatibility
+
+  silence_redefinition_of_method :to_time
+
+  # Either return an instance of +Time+ with the same UTC offset
+  # as +self+ or an instance of +Time+ representing the same time
+  # in the the local system timezone depending on the setting of
+  # on the setting of +ActiveSupport.to_time_preserves_timezone+.
+  def to_time
+    preserve_timezone ? getlocal(utc_offset) : getlocal
+  end
 end
diff --git a/activesupport/lib/active_support/core_ext/date_time/conversions.rb b/activesupport/lib/active_support/core_ext/date_time/conversions.rb
index f59d05b214..29725c89f7 100644
--- a/activesupport/lib/active_support/core_ext/date_time/conversions.rb
+++ b/activesupport/lib/active_support/core_ext/date_time/conversions.rb
@@ -1,8 +1,10 @@
-require 'date'
-require 'active_support/inflector/methods'
-require 'active_support/core_ext/time/conversions'
-require 'active_support/core_ext/date_time/calculations'
-require 'active_support/values/time_zone'
+# frozen_string_literal: true
+
+require "date"
+require "active_support/inflector/methods"
+require "active_support/core_ext/time/conversions"
+require "active_support/core_ext/date_time/calculations"
+require "active_support/values/time_zone"
 
 class DateTime
   # Convert to a formatted string. See Time::DATE_FORMATS for predefined formats.
@@ -64,7 +66,7 @@ class DateTime
   #   # => Sun, 01 Jan 2012 00:00:00 +0300
   #   DateTime.civil_from_format :local, 2012, 12, 17
   #   # => Mon, 17 Dec 2012 00:00:00 +0000
-  def self.civil_from_format(utc_or_local, year, month=1, day=1, hour=0, min=0, sec=0)
+  def self.civil_from_format(utc_or_local, year, month = 1, day = 1, hour = 0, min = 0, sec = 0)
     if utc_or_local.to_sym == :local
       offset = ::Time.local(year, month, day).utc_offset.to_r / 86400
     else
@@ -95,11 +97,11 @@ class DateTime
 
   private
 
-  def offset_in_seconds
-    (offset * 86400).to_i
-  end
+    def offset_in_seconds
+      (offset * 86400).to_i
+    end
 
-  def seconds_since_unix_epoch
-    (jd - 2440588) * 86400 - offset_in_seconds + seconds_since_midnight
-  end
+    def seconds_since_unix_epoch
+      (jd - 2440588) * 86400 - offset_in_seconds + seconds_since_midnight
+    end
 end
diff --git a/activesupport/lib/active_support/core_ext/digest/uuid.rb b/activesupport/lib/active_support/core_ext/digest/uuid.rb
index 593c51bba2..6e949a2d72 100644
--- a/activesupport/lib/active_support/core_ext/digest/uuid.rb
+++ b/activesupport/lib/active_support/core_ext/digest/uuid.rb
@@ -1,4 +1,6 @@
-require 'securerandom'
+# frozen_string_literal: true
+
+require "securerandom"
 
 module Digest
   module UUID
@@ -12,7 +14,7 @@ module Digest
     # Using Digest::MD5 generates version 3 UUIDs; Digest::SHA1 generates version 5 UUIDs.
     # uuid_from_hash always generates the same UUID for a given name and namespace combination.
     #
-    # See RFC 4122 for details of UUID at: http://www.ietf.org/rfc/rfc4122.txt
+    # See RFC 4122 for details of UUID at: https://www.ietf.org/rfc/rfc4122.txt
     def self.uuid_from_hash(hash_class, uuid_namespace, name)
       if hash_class == Digest::MD5
         version = 3
@@ -26,7 +28,7 @@ module Digest
       hash.update(uuid_namespace)
       hash.update(name)
 
-      ary = hash.digest.unpack('NnnnnN')
+      ary = hash.digest.unpack("NnnnnN")
       ary[2] = (ary[2] & 0x0FFF) | (version << 12)
       ary[3] = (ary[3] & 0x3FFF) | 0x8000
 
@@ -35,12 +37,12 @@ module Digest
 
     # Convenience method for uuid_from_hash using Digest::MD5.
     def self.uuid_v3(uuid_namespace, name)
-      self.uuid_from_hash(Digest::MD5, uuid_namespace, name)
+      uuid_from_hash(Digest::MD5, uuid_namespace, name)
     end
 
     # Convenience method for uuid_from_hash using Digest::SHA1.
     def self.uuid_v5(uuid_namespace, name)
-      self.uuid_from_hash(Digest::SHA1, uuid_namespace, name)
+      uuid_from_hash(Digest::SHA1, uuid_namespace, name)
     end
 
     # Convenience method for SecureRandom.uuid.
diff --git a/activesupport/lib/active_support/core_ext/enumerable.rb b/activesupport/lib/active_support/core_ext/enumerable.rb
index 8ebe758078..17733d955c 100644
--- a/activesupport/lib/active_support/core_ext/enumerable.rb
+++ b/activesupport/lib/active_support/core_ext/enumerable.rb
@@ -1,37 +1,61 @@
+# frozen_string_literal: true
+
 module Enumerable
-  # Calculates a sum from the elements.
-  #
-  #  payments.sum { |p| p.price * p.tax_rate }
-  #  payments.sum(&:price)
-  #
-  # The latter is a shortcut for:
-  #
-  #  payments.inject(0) { |sum, p| sum + p.price }
-  #
-  # It can also calculate the sum without the use of a block.
+  # Enumerable#sum was added in Ruby 2.4, but it only works with Numeric elements
+  # when we omit an identity.
   #
-  #  [5, 15, 10].sum # => 30
-  #  ['foo', 'bar'].sum # => "foobar"
-  #  [[1, 2], [3, 1, 5]].sum => [1, 2, 3, 1, 5]
-  #
-  # The default sum of an empty list is zero. You can override this default:
-  #
-  #  [].sum(Payment.new(0)) { |i| i.amount } # => Payment.new(0)
-  def sum(identity = nil, &block)
-    if block_given?
-      map(&block).sum(identity)
-    else
-      sum = identity ? inject(identity, :+) : inject(:+)
-      sum || identity || 0
+  # We tried shimming it to attempt the fast native method, rescue TypeError,
+  # and fall back to the compatible implementation, but that's much slower than
+  # just calling the compat method in the first place.
+  if Enumerable.instance_methods(false).include?(:sum) && !((?a..?b).sum rescue false)
+    # We can't use Refinements here because Refinements with Module which will be prepended
+    # doesn't work well https://bugs.ruby-lang.org/issues/13446
+    alias :_original_sum_with_required_identity :sum
+    private :_original_sum_with_required_identity
+    # Calculates a sum from the elements.
+    #
+    #  payments.sum { |p| p.price * p.tax_rate }
+    #  payments.sum(&:price)
+    #
+    # The latter is a shortcut for:
+    #
+    #  payments.inject(0) { |sum, p| sum + p.price }
+    #
+    # It can also calculate the sum without the use of a block.
+    #
+    #  [5, 15, 10].sum # => 30
+    #  ['foo', 'bar'].sum # => "foobar"
+    #  [[1, 2], [3, 1, 5]].sum # => [1, 2, 3, 1, 5]
+    #
+    # The default sum of an empty list is zero. You can override this default:
+    #
+    #  [].sum(Payment.new(0)) { |i| i.amount } # => Payment.new(0)
+    def sum(identity = nil, &block)
+      if identity
+        _original_sum_with_required_identity(identity, &block)
+      elsif block_given?
+        map(&block).sum(identity)
+      else
+        inject(:+) || 0
+      end
+    end
+  else
+    def sum(identity = nil, &block)
+      if block_given?
+        map(&block).sum(identity)
+      else
+        sum = identity ? inject(identity, :+) : inject(:+)
+        sum || identity || 0
+      end
     end
   end
 
   # Convert an enumerable to a hash.
   #
   #   people.index_by(&:login)
-  #     => { "nextangle" => <Person ...>, "chade-" => <Person ...>, ...}
+  #   # => { "nextangle" => <Person ...>, "chade-" => <Person ...>, ...}
   #   people.index_by { |person| "#{person.first_name} #{person.last_name}" }
-  #     => { "Chade- Fowlersburg-e" => <Person ...>, "David Heinemeier Hansson" => <Person ...>, ...}
+  #   # => { "Chade- Fowlersburg-e" => <Person ...>, "David Heinemeier Hansson" => <Person ...>, ...}
   def index_by
     if block_given?
       result = {}
@@ -67,10 +91,10 @@ module Enumerable
   # Returns a copy of the enumerable without the specified elements.
   #
   #   ["David", "Rafael", "Aaron", "Todd"].without "Aaron", "Todd"
-  #     => ["David", "Rafael"]
+  #   # => ["David", "Rafael"]
   #
   #   {foo: 1, bar: 2, baz: 3}.without :bar
-  #     => {foo: 1, baz: 3}
+  #   # => {foo: 1, baz: 3}
   def without(*elements)
     reject { |element| elements.include?(element) }
   end
@@ -78,10 +102,10 @@ module Enumerable
   # Convert an enumerable to an array based on the given key.
   #
   #   [{ name: "David" }, { name: "Rafael" }, { name: "Aaron" }].pluck(:name)
-  #     => ["David", "Rafael", "Aaron"]
+  #   # => ["David", "Rafael", "Aaron"]
   #
   #   [{ id: 1, name: "David" }, { id: 2, name: "Rafael" }].pluck(:id, :name)
-  #     => [[1, "David"], [2, "Rafael"]]
+  #   # => [[1, "David"], [2, "Rafael"]]
   def pluck(*keys)
     if keys.many?
       map { |element| keys.map { |key| element[key] } }
@@ -115,9 +139,14 @@ end
 # and fall back to the compatible implementation, but that's much slower than
 # just calling the compat method in the first place.
 if Array.instance_methods(false).include?(:sum) && !(%w[a].sum rescue false)
-  class Array
-    alias :orig_sum :sum
+  # Using Refinements here in order not to expose our internal method
+  using Module.new {
+    refine Array do
+      alias :orig_sum :sum
+    end
+  }
 
+  class Array
     def sum(init = nil, &block) #:nodoc:
       if init.is_a?(Numeric) || first.is_a?(Numeric)
         init ||= 0
diff --git a/activesupport/lib/active_support/core_ext/file.rb b/activesupport/lib/active_support/core_ext/file.rb
index dc24afbe7f..64553bfa4e 100644
--- a/activesupport/lib/active_support/core_ext/file.rb
+++ b/activesupport/lib/active_support/core_ext/file.rb
@@ -1 +1,3 @@
-require 'active_support/core_ext/file/atomic'
+# frozen_string_literal: true
+
+require "active_support/core_ext/file/atomic"
diff --git a/activesupport/lib/active_support/core_ext/file/atomic.rb b/activesupport/lib/active_support/core_ext/file/atomic.rb
index 463fd78412..8e288833b6 100644
--- a/activesupport/lib/active_support/core_ext/file/atomic.rb
+++ b/activesupport/lib/active_support/core_ext/file/atomic.rb
@@ -1,4 +1,6 @@
-require 'fileutils'
+# frozen_string_literal: true
+
+require "fileutils"
 
 class File
   # Write to a file atomically. Useful for situations where you don't
@@ -17,7 +19,7 @@ class File
   #     file.write('hello')
   #   end
   def self.atomic_write(file_name, temp_dir = dirname(file_name))
-    require 'tempfile' unless defined?(Tempfile)
+    require "tempfile" unless defined?(Tempfile)
 
     Tempfile.open(".#{basename(file_name)}", temp_dir) do |temp_file|
       temp_file.binmode
@@ -53,11 +55,11 @@ class File
   # Private utility method.
   def self.probe_stat_in(dir) #:nodoc:
     basename = [
-      '.permissions_check',
+      ".permissions_check",
       Thread.current.object_id,
       Process.pid,
       rand(1000000)
-    ].join('.')
+    ].join(".")
 
     file_name = join(dir, basename)
     FileUtils.touch(file_name)
diff --git a/activesupport/lib/active_support/core_ext/hash.rb b/activesupport/lib/active_support/core_ext/hash.rb
index af4d1da0eb..e19aeaa983 100644
--- a/activesupport/lib/active_support/core_ext/hash.rb
+++ b/activesupport/lib/active_support/core_ext/hash.rb
@@ -1,9 +1,11 @@
-require 'active_support/core_ext/hash/compact'
-require 'active_support/core_ext/hash/conversions'
-require 'active_support/core_ext/hash/deep_merge'
-require 'active_support/core_ext/hash/except'
-require 'active_support/core_ext/hash/indifferent_access'
-require 'active_support/core_ext/hash/keys'
-require 'active_support/core_ext/hash/reverse_merge'
-require 'active_support/core_ext/hash/slice'
-require 'active_support/core_ext/hash/transform_values'
+# frozen_string_literal: true
+
+require "active_support/core_ext/hash/compact"
+require "active_support/core_ext/hash/conversions"
+require "active_support/core_ext/hash/deep_merge"
+require "active_support/core_ext/hash/except"
+require "active_support/core_ext/hash/indifferent_access"
+require "active_support/core_ext/hash/keys"
+require "active_support/core_ext/hash/reverse_merge"
+require "active_support/core_ext/hash/slice"
+require "active_support/core_ext/hash/transform_values"
diff --git a/activesupport/lib/active_support/core_ext/hash/compact.rb b/activesupport/lib/active_support/core_ext/hash/compact.rb
index f072530e04..d6364dd9f3 100644
--- a/activesupport/lib/active_support/core_ext/hash/compact.rb
+++ b/activesupport/lib/active_support/core_ext/hash/compact.rb
@@ -1,23 +1,29 @@
+# frozen_string_literal: true
+
 class Hash
-  # Returns a hash with non +nil+ values.
-  #
-  #   hash = { a: true, b: false, c: nil }
-  #   hash.compact        # => { a: true, b: false }
-  #   hash                # => { a: true, b: false, c: nil }
-  #   { c: nil }.compact  # => {}
-  #   { c: true }.compact # => { c: true }
-  def compact
-    self.select { |_, value| !value.nil? }
+  unless Hash.instance_methods(false).include?(:compact)
+    # Returns a hash with non +nil+ values.
+    #
+    #   hash = { a: true, b: false, c: nil }
+    #   hash.compact        # => { a: true, b: false }
+    #   hash                # => { a: true, b: false, c: nil }
+    #   { c: nil }.compact  # => {}
+    #   { c: true }.compact # => { c: true }
+    def compact
+      select { |_, value| !value.nil? }
+    end
   end
 
-  # Replaces current hash with non +nil+ values.
-  # Returns nil if no changes were made, otherwise returns the hash.
-  #
-  #   hash = { a: true, b: false, c: nil }
-  #   hash.compact!        # => { a: true, b: false }
-  #   hash                 # => { a: true, b: false }
-  #   { c: true }.compact! # => nil
-  def compact!
-    self.reject! { |_, value| value.nil? }
+  unless Hash.instance_methods(false).include?(:compact!)
+    # Replaces current hash with non +nil+ values.
+    # Returns +nil+ if no changes were made, otherwise returns the hash.
+    #
+    #   hash = { a: true, b: false, c: nil }
+    #   hash.compact!        # => { a: true, b: false }
+    #   hash                 # => { a: true, b: false }
+    #   { c: true }.compact! # => nil
+    def compact!
+      reject! { |_, value| value.nil? }
+    end
   end
 end
diff --git a/activesupport/lib/active_support/core_ext/hash/conversions.rb b/activesupport/lib/active_support/core_ext/hash/conversions.rb
index 2fc514cfce..11d28d12a1 100644
--- a/activesupport/lib/active_support/core_ext/hash/conversions.rb
+++ b/activesupport/lib/active_support/core_ext/hash/conversions.rb
@@ -1,11 +1,13 @@
-require 'active_support/xml_mini'
-require 'active_support/time'
-require 'active_support/core_ext/object/blank'
-require 'active_support/core_ext/object/to_param'
-require 'active_support/core_ext/object/to_query'
-require 'active_support/core_ext/array/wrap'
-require 'active_support/core_ext/hash/reverse_merge'
-require 'active_support/core_ext/string/inflections'
+# frozen_string_literal: true
+
+require "active_support/xml_mini"
+require "active_support/time"
+require "active_support/core_ext/object/blank"
+require "active_support/core_ext/object/to_param"
+require "active_support/core_ext/object/to_query"
+require "active_support/core_ext/array/wrap"
+require "active_support/core_ext/hash/reverse_merge"
+require "active_support/core_ext/string/inflections"
 
 class Hash
   # Returns a string containing an XML representation of its receiver:
@@ -71,11 +73,11 @@ class Hash
   # configure your own builder with the <tt>:builder</tt> option. The method also accepts
   # options like <tt>:dasherize</tt> and friends, they are forwarded to the builder.
   def to_xml(options = {})
-    require 'active_support/builder' unless defined?(Builder)
+    require "active_support/builder" unless defined?(Builder)
 
     options = options.dup
     options[:indent]  ||= 2
-    options[:root]    ||= 'hash'
+    options[:root]    ||= "hash"
     options[:builder] ||= Builder::XmlMarkup.new(indent: options[:indent])
 
     builder = options[:builder]
@@ -159,36 +161,36 @@ module ActiveSupport
     private
       def normalize_keys(params)
         case params
-          when Hash
-            Hash[params.map { |k,v| [k.to_s.tr('-', '_'), normalize_keys(v)] } ]
-          when Array
-            params.map { |v| normalize_keys(v) }
+        when Hash
+          Hash[params.map { |k, v| [k.to_s.tr("-", "_"), normalize_keys(v)] } ]
+        when Array
+          params.map { |v| normalize_keys(v) }
           else
-            params
+          params
         end
       end
 
       def deep_to_h(value)
         case value
-          when Hash
-            process_hash(value)
-          when Array
-            process_array(value)
-          when String
-            value
+        when Hash
+          process_hash(value)
+        when Array
+          process_array(value)
+        when String
+          value
           else
-            raise "can't typecast #{value.class.name} - #{value.inspect}"
+          raise "can't typecast #{value.class.name} - #{value.inspect}"
         end
       end
 
       def process_hash(value)
-        if value.include?('type') && !value['type'].is_a?(Hash) && @disallowed_types.include?(value['type'])
-          raise DisallowedType, value['type']
+        if value.include?("type") && !value["type"].is_a?(Hash) && @disallowed_types.include?(value["type"])
+          raise DisallowedType, value["type"]
         end
 
         if become_array?(value)
-          _, entries = Array.wrap(value.detect { |k,v| not v.is_a?(String) })
-          if entries.nil? || value['__content__'].try(:empty?)
+          _, entries = Array.wrap(value.detect { |k, v| not v.is_a?(String) })
+          if entries.nil? || value["__content__"].try(:empty?)
             []
           else
             case entries
@@ -204,28 +206,28 @@ module ActiveSupport
           process_content(value)
 
         elsif become_empty_string?(value)
-          ''
+          ""
         elsif become_hash?(value)
-          xml_value = Hash[value.map { |k,v| [k, deep_to_h(v)] }]
+          xml_value = Hash[value.map { |k, v| [k, deep_to_h(v)] }]
 
           # Turn { files: { file: #<StringIO> } } into { files: #<StringIO> } so it is compatible with
           # how multipart uploaded files from HTML appear
-          xml_value['file'].is_a?(StringIO) ? xml_value['file'] : xml_value
+          xml_value["file"].is_a?(StringIO) ? xml_value["file"] : xml_value
         end
       end
 
       def become_content?(value)
-        value['type'] == 'file' || (value['__content__'] && (value.keys.size == 1 || value['__content__'].present?))
+        value["type"] == "file" || (value["__content__"] && (value.keys.size == 1 || value["__content__"].present?))
       end
 
       def become_array?(value)
-        value['type'] == 'array'
+        value["type"] == "array"
       end
 
       def become_empty_string?(value)
         # { "string" => true }
         # No tests fail when the second term is removed.
-        value['type'] == 'string' && value['nil'] != 'true'
+        value["type"] == "string" && value["nil"] != "true"
       end
 
       def become_hash?(value)
@@ -234,19 +236,19 @@ module ActiveSupport
 
       def nothing?(value)
         # blank or nil parsed values are represented by nil
-        value.blank? || value['nil'] == 'true'
+        value.blank? || value["nil"] == "true"
       end
 
       def garbage?(value)
         # If the type is the only element which makes it then
         # this still makes the value nil, except if type is
         # an XML node(where type['value'] is a Hash)
-        value['type'] && !value['type'].is_a?(::Hash) && value.size == 1
+        value["type"] && !value["type"].is_a?(::Hash) && value.size == 1
       end
 
       def process_content(value)
-        content = value['__content__']
-        if parser = ActiveSupport::XmlMini::PARSING[value['type']]
+        content = value["__content__"]
+        if parser = ActiveSupport::XmlMini::PARSING[value["type"]]
           parser.arity == 1 ? parser.call(content) : parser.call(content, value)
         else
           content
@@ -257,6 +259,5 @@ module ActiveSupport
         value.map! { |i| deep_to_h(i) }
         value.length > 1 ? value : value.first
       end
-
   end
 end
diff --git a/activesupport/lib/active_support/core_ext/hash/deep_merge.rb b/activesupport/lib/active_support/core_ext/hash/deep_merge.rb
index 9c9faf67ea..9bc50b7bc6 100644
--- a/activesupport/lib/active_support/core_ext/hash/deep_merge.rb
+++ b/activesupport/lib/active_support/core_ext/hash/deep_merge.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Hash
   # Returns a new hash with +self+ and +other_hash+ merged recursively.
   #
@@ -19,20 +21,14 @@ class Hash
 
   # Same as +deep_merge+, but modifies +self+.
   def deep_merge!(other_hash, &block)
-    other_hash.each_pair do |current_key, other_value|
-      this_value = self[current_key]
-
-      self[current_key] = if this_value.is_a?(Hash) && other_value.is_a?(Hash)
-        this_value.deep_merge(other_value, &block)
+    merge!(other_hash) do |key, this_val, other_val|
+      if this_val.is_a?(Hash) && other_val.is_a?(Hash)
+        this_val.deep_merge(other_val, &block)
+      elsif block_given?
+        block.call(key, this_val, other_val)
       else
-        if block_given? && key?(current_key)
-          block.call(current_key, this_value, other_value)
-        else
-          other_value
-        end
+        other_val
       end
     end
-
-    self
   end
 end
diff --git a/activesupport/lib/active_support/core_ext/hash/except.rb b/activesupport/lib/active_support/core_ext/hash/except.rb
index 2f6d38c1f6..6258610c98 100644
--- a/activesupport/lib/active_support/core_ext/hash/except.rb
+++ b/activesupport/lib/active_support/core_ext/hash/except.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Hash
   # Returns a hash that includes everything except given keys.
   #   hash = { a: true, b: false, c: nil }
diff --git a/activesupport/lib/active_support/core_ext/hash/indifferent_access.rb b/activesupport/lib/active_support/core_ext/hash/indifferent_access.rb
index 6df7b4121b..a38f33f128 100644
--- a/activesupport/lib/active_support/core_ext/hash/indifferent_access.rb
+++ b/activesupport/lib/active_support/core_ext/hash/indifferent_access.rb
@@ -1,7 +1,8 @@
-require 'active_support/hash_with_indifferent_access'
+# frozen_string_literal: true
 
-class Hash
+require "active_support/hash_with_indifferent_access"
 
+class Hash
   # Returns an <tt>ActiveSupport::HashWithIndifferentAccess</tt> out of its receiver:
   #
   #   { a: 1 }.with_indifferent_access['a'] # => 1
diff --git a/activesupport/lib/active_support/core_ext/hash/keys.rb b/activesupport/lib/active_support/core_ext/hash/keys.rb
index 1bfa18aeee..bdf196ec3d 100644
--- a/activesupport/lib/active_support/core_ext/hash/keys.rb
+++ b/activesupport/lib/active_support/core_ext/hash/keys.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Hash
   # Returns a new hash with all keys converted using the +block+ operation.
   #
@@ -16,7 +18,7 @@ class Hash
       result[yield(key)] = self[key]
     end
     result
-  end
+  end unless method_defined? :transform_keys
 
   # Destructively converts all keys using the +block+ operations.
   # Same as +transform_keys+ but modifies +self+.
@@ -26,7 +28,7 @@ class Hash
       self[yield(key)] = delete(key)
     end
     self
-  end
+  end unless method_defined? :transform_keys!
 
   # Returns a new hash with all keys converted to strings.
   #
@@ -52,14 +54,14 @@ class Hash
   #   hash.symbolize_keys
   #   # => {:name=>"Rob", :age=>"28"}
   def symbolize_keys
-    transform_keys{ |key| key.to_sym rescue key }
+    transform_keys { |key| key.to_sym rescue key }
   end
   alias_method :to_options,  :symbolize_keys
 
   # Destructively converts all keys to symbols, as long as they respond
   # to +to_sym+. Same as +symbolize_keys+, but modifies +self+.
   def symbolize_keys!
-    transform_keys!{ |key| key.to_sym rescue key }
+    transform_keys! { |key| key.to_sym rescue key }
   end
   alias_method :to_options!, :symbolize_keys!
 
@@ -128,14 +130,14 @@ class Hash
   #   hash.deep_symbolize_keys
   #   # => {:person=>{:name=>"Rob", :age=>"28"}}
   def deep_symbolize_keys
-    deep_transform_keys{ |key| key.to_sym rescue key }
+    deep_transform_keys { |key| key.to_sym rescue key }
   end
 
   # Destructively converts all keys to symbols, as long as they respond
   # to +to_sym+. This includes the keys from the root hash and from all
   # nested hashes and arrays.
   def deep_symbolize_keys!
-    deep_transform_keys!{ |key| key.to_sym rescue key }
+    deep_transform_keys! { |key| key.to_sym rescue key }
   end
 
   private
@@ -147,7 +149,7 @@ class Hash
           result[yield(key)] = _deep_transform_keys_in_object(value, &block)
         end
       when Array
-        object.map {|e| _deep_transform_keys_in_object(e, &block) }
+        object.map { |e| _deep_transform_keys_in_object(e, &block) }
       else
         object
       end
@@ -162,7 +164,7 @@ class Hash
         end
         object
       when Array
-        object.map! {|e| _deep_transform_keys_in_object!(e, &block)}
+        object.map! { |e| _deep_transform_keys_in_object!(e, &block) }
       else
         object
       end
diff --git a/activesupport/lib/active_support/core_ext/hash/reverse_merge.rb b/activesupport/lib/active_support/core_ext/hash/reverse_merge.rb
index fbb482435d..ef8d592829 100644
--- a/activesupport/lib/active_support/core_ext/hash/reverse_merge.rb
+++ b/activesupport/lib/active_support/core_ext/hash/reverse_merge.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Hash
   # Merges the caller into +other_hash+. For example,
   #
@@ -12,11 +14,12 @@ class Hash
   def reverse_merge(other_hash)
     other_hash.merge(self)
   end
+  alias_method :with_defaults, :reverse_merge
 
   # Destructive +reverse_merge+.
   def reverse_merge!(other_hash)
-    # right wins if there is no left
-    merge!( other_hash ){|key,left,right| left }
+    replace(reverse_merge(other_hash))
   end
   alias_method :reverse_update, :reverse_merge!
+  alias_method :with_defaults!, :reverse_merge!
 end
diff --git a/activesupport/lib/active_support/core_ext/hash/slice.rb b/activesupport/lib/active_support/core_ext/hash/slice.rb
index 1d5f38231a..2bd0a56ea4 100644
--- a/activesupport/lib/active_support/core_ext/hash/slice.rb
+++ b/activesupport/lib/active_support/core_ext/hash/slice.rb
@@ -1,11 +1,13 @@
+# frozen_string_literal: true
+
 class Hash
-  # Slices a hash to include only the given keys. Returns a hash containing 
+  # Slices a hash to include only the given keys. Returns a hash containing
   # the given keys.
-  # 
+  #
   #   { a: 1, b: 2, c: 3, d: 4 }.slice(:a, :b)
   #   # => {:a=>1, :b=>2}
-  # 
-  # This is useful for limiting an options hash to valid keys before 
+  #
+  # This is useful for limiting an options hash to valid keys before
   # passing to a method:
   #
   #   def search(criteria = {})
@@ -19,9 +21,8 @@ class Hash
   #   valid_keys = [:mass, :velocity, :time]
   #   search(options.slice(*valid_keys))
   def slice(*keys)
-    keys.map! { |key| convert_key(key) } if respond_to?(:convert_key, true)
-    keys.each_with_object(self.class.new) { |k, hash| hash[k] = self[k] if has_key?(k) }
-  end
+    keys.each_with_object(Hash.new) { |k, hash| hash[k] = self[k] if has_key?(k) }
+  end unless method_defined?(:slice)
 
   # Replaces the hash with only the given keys.
   # Returns a hash containing the removed key/value pairs.
@@ -29,7 +30,6 @@ class Hash
   #   { a: 1, b: 2, c: 3, d: 4 }.slice!(:a, :b)
   #   # => {:c=>3, :d=>4}
   def slice!(*keys)
-    keys.map! { |key| convert_key(key) } if respond_to?(:convert_key, true)
     omit = slice(*self.keys - keys)
     hash = slice(*keys)
     hash.default      = default
diff --git a/activesupport/lib/active_support/core_ext/hash/transform_values.rb b/activesupport/lib/active_support/core_ext/hash/transform_values.rb
index 7d507ac998..4b19c9fc1f 100644
--- a/activesupport/lib/active_support/core_ext/hash/transform_values.rb
+++ b/activesupport/lib/active_support/core_ext/hash/transform_values.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Hash
   # Returns a new hash with the results of running +block+ once for every value.
   # The keys are unchanged.
@@ -16,7 +18,7 @@ class Hash
       result[key] = yield(value)
     end
     result
-  end
+  end unless method_defined? :transform_values
 
   # Destructively converts all values using the +block+ operations.
   # Same as +transform_values+ but modifies +self+.
@@ -25,5 +27,6 @@ class Hash
     each do |key, value|
       self[key] = yield(value)
     end
-  end
+  end unless method_defined? :transform_values!
+  # TODO: Remove this file when supporting only Ruby 2.4+.
 end
diff --git a/activesupport/lib/active_support/core_ext/integer.rb b/activesupport/lib/active_support/core_ext/integer.rb
index a44a1b4c74..d22701306a 100644
--- a/activesupport/lib/active_support/core_ext/integer.rb
+++ b/activesupport/lib/active_support/core_ext/integer.rb
@@ -1,3 +1,5 @@
-require 'active_support/core_ext/integer/multiple'
-require 'active_support/core_ext/integer/inflections'
-require 'active_support/core_ext/integer/time'
+# frozen_string_literal: true
+
+require "active_support/core_ext/integer/multiple"
+require "active_support/core_ext/integer/inflections"
+require "active_support/core_ext/integer/time"
diff --git a/activesupport/lib/active_support/core_ext/integer/inflections.rb b/activesupport/lib/active_support/core_ext/integer/inflections.rb
index 56f2ed5985..aef3266f28 100644
--- a/activesupport/lib/active_support/core_ext/integer/inflections.rb
+++ b/activesupport/lib/active_support/core_ext/integer/inflections.rb
@@ -1,4 +1,6 @@
-require 'active_support/inflector'
+# frozen_string_literal: true
+
+require "active_support/inflector"
 
 class Integer
   # Ordinalize turns a number into an ordinal string used to denote the
diff --git a/activesupport/lib/active_support/core_ext/integer/multiple.rb b/activesupport/lib/active_support/core_ext/integer/multiple.rb
index c668c7c2eb..e7606662d3 100644
--- a/activesupport/lib/active_support/core_ext/integer/multiple.rb
+++ b/activesupport/lib/active_support/core_ext/integer/multiple.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Integer
   # Check whether the integer is evenly divisible by the argument.
   #
diff --git a/activesupport/lib/active_support/core_ext/integer/time.rb b/activesupport/lib/active_support/core_ext/integer/time.rb
index 87185b024f..5efb89cf9f 100644
--- a/activesupport/lib/active_support/core_ext/integer/time.rb
+++ b/activesupport/lib/active_support/core_ext/integer/time.rb
@@ -1,29 +1,22 @@
-require 'active_support/duration'
-require 'active_support/core_ext/numeric/time'
+# frozen_string_literal: true
+
+require "active_support/duration"
+require "active_support/core_ext/numeric/time"
 
 class Integer
-  # Enables the use of time calculations and declarations, like <tt>45.minutes +
-  # 2.hours + 4.years</tt>.
-  #
-  # These methods use Time#advance for precise date calculations when using
-  # <tt>from_now</tt>, +ago+, etc. as well as adding or subtracting their
-  # results from a Time object.
-  #
-  #   # equivalent to Time.now.advance(months: 1)
-  #   1.month.from_now
+  # Returns a Duration instance matching the number of months provided.
   #
-  #   # equivalent to Time.now.advance(years: 2)
-  #   2.years.from_now
-  #
-  #   # equivalent to Time.now.advance(months: 4, years: 5)
-  #   (4.months + 5.years).from_now
+  #   2.months # => 2 months
   def months
-    ActiveSupport::Duration.new(self * 30.days, [[:months, self]])
+    ActiveSupport::Duration.months(self)
   end
   alias :month :months
 
+  # Returns a Duration instance matching the number of years provided.
+  #
+  #   2.years # => 2 years
   def years
-    ActiveSupport::Duration.new(self * 365.25.days.to_i, [[:years, self]])
+    ActiveSupport::Duration.years(self)
   end
   alias :year :years
 end
diff --git a/activesupport/lib/active_support/core_ext/kernel.rb b/activesupport/lib/active_support/core_ext/kernel.rb
index 364ed9d65f..0f4356fbdd 100644
--- a/activesupport/lib/active_support/core_ext/kernel.rb
+++ b/activesupport/lib/active_support/core_ext/kernel.rb
@@ -1,4 +1,6 @@
-require 'active_support/core_ext/kernel/agnostics'
-require 'active_support/core_ext/kernel/concern'
-require 'active_support/core_ext/kernel/reporting'
-require 'active_support/core_ext/kernel/singleton_class'
+# frozen_string_literal: true
+
+require "active_support/core_ext/kernel/agnostics"
+require "active_support/core_ext/kernel/concern"
+require "active_support/core_ext/kernel/reporting"
+require "active_support/core_ext/kernel/singleton_class"
diff --git a/activesupport/lib/active_support/core_ext/kernel/agnostics.rb b/activesupport/lib/active_support/core_ext/kernel/agnostics.rb
index 64837d87aa..403b5f31f0 100644
--- a/activesupport/lib/active_support/core_ext/kernel/agnostics.rb
+++ b/activesupport/lib/active_support/core_ext/kernel/agnostics.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Object
   # Makes backticks behave (somewhat more) similarly on all platforms.
   # On win32 `nonexistent_command` raises Errno::ENOENT; on Unix, the
diff --git a/activesupport/lib/active_support/core_ext/kernel/concern.rb b/activesupport/lib/active_support/core_ext/kernel/concern.rb
index 18bcc01fa4..0b2baed780 100644
--- a/activesupport/lib/active_support/core_ext/kernel/concern.rb
+++ b/activesupport/lib/active_support/core_ext/kernel/concern.rb
@@ -1,4 +1,6 @@
-require 'active_support/core_ext/module/concerning'
+# frozen_string_literal: true
+
+require "active_support/core_ext/module/concerning"
 
 module Kernel
   module_function
diff --git a/activesupport/lib/active_support/core_ext/kernel/debugger.rb b/activesupport/lib/active_support/core_ext/kernel/debugger.rb
deleted file mode 100644
index 1fde3db070..0000000000
--- a/activesupport/lib/active_support/core_ext/kernel/debugger.rb
+++ /dev/null
@@ -1,3 +0,0 @@
-require 'active_support/deprecation'
-
-ActiveSupport::Deprecation.warn("This file is deprecated and will be removed in Rails 5.1 with no replacement.")
diff --git a/activesupport/lib/active_support/core_ext/kernel/reporting.rb b/activesupport/lib/active_support/core_ext/kernel/reporting.rb
index d0197af95f..9155bd6c10 100644
--- a/activesupport/lib/active_support/core_ext/kernel/reporting.rb
+++ b/activesupport/lib/active_support/core_ext/kernel/reporting.rb
@@ -1,7 +1,9 @@
+# frozen_string_literal: true
+
 module Kernel
   module_function
 
-  # Sets $VERBOSE to nil for the duration of the block and back to its original
+  # Sets $VERBOSE to +nil+ for the duration of the block and back to its original
   # value afterwards.
   #
   #   silence_warnings do
diff --git a/activesupport/lib/active_support/core_ext/kernel/singleton_class.rb b/activesupport/lib/active_support/core_ext/kernel/singleton_class.rb
index 9bbf1bbd73..6715eba80a 100644
--- a/activesupport/lib/active_support/core_ext/kernel/singleton_class.rb
+++ b/activesupport/lib/active_support/core_ext/kernel/singleton_class.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module Kernel
   # class_eval on an object acts like singleton_class.class_eval.
   def class_eval(*args, &block)
diff --git a/activesupport/lib/active_support/core_ext/load_error.rb b/activesupport/lib/active_support/core_ext/load_error.rb
index 60732eb41a..750f858fcc 100644
--- a/activesupport/lib/active_support/core_ext/load_error.rb
+++ b/activesupport/lib/active_support/core_ext/load_error.rb
@@ -1,30 +1,9 @@
-require 'active_support/deprecation/proxy_wrappers'
+# frozen_string_literal: true
 
 class LoadError
-  REGEXPS = [
-    /^no such file to load -- (.+)$/i,
-    /^Missing \w+ (?:file\s*)?([^\s]+.rb)$/i,
-    /^Missing API definition file in (.+)$/i,
-    /^cannot load such file -- (.+)$/i,
-  ]
-
-  unless method_defined?(:path)
-    # Returns the path which was unable to be loaded.
-    def path
-      @path ||= begin
-        REGEXPS.find do |regex|
-          message =~ regex
-        end
-        $1
-      end
-    end
-  end
-
   # Returns true if the given path name (except perhaps for the ".rb"
   # extension) is the missing file which caused the exception to be raised.
   def is_missing?(location)
-    location.sub(/\.rb$/, ''.freeze) == path.sub(/\.rb$/, ''.freeze)
+    location.sub(/\.rb$/, "".freeze) == path.sub(/\.rb$/, "".freeze)
   end
 end
-
-MissingSourceFile = ActiveSupport::Deprecation::DeprecatedConstantProxy.new('MissingSourceFile', 'LoadError')
diff --git a/activesupport/lib/active_support/core_ext/marshal.rb b/activesupport/lib/active_support/core_ext/marshal.rb
index edfc8296fe..0c72cd7b47 100644
--- a/activesupport/lib/active_support/core_ext/marshal.rb
+++ b/activesupport/lib/active_support/core_ext/marshal.rb
@@ -1,7 +1,9 @@
+# frozen_string_literal: true
+
 module ActiveSupport
   module MarshalWithAutoloading # :nodoc:
-    def load(source)
-      super(source)
+    def load(source, proc = nil)
+      super(source, proc)
     rescue ArgumentError, NameError => exc
       if exc.message.match(%r|undefined class/module (.+?)(?:::)?\z|)
         # try loading the class/module
diff --git a/activesupport/lib/active_support/core_ext/module.rb b/activesupport/lib/active_support/core_ext/module.rb
index ef038331c2..d91e3fba6a 100644
--- a/activesupport/lib/active_support/core_ext/module.rb
+++ b/activesupport/lib/active_support/core_ext/module.rb
@@ -1,12 +1,14 @@
-require 'active_support/core_ext/module/aliasing'
-require 'active_support/core_ext/module/introspection'
-require 'active_support/core_ext/module/anonymous'
-require 'active_support/core_ext/module/reachable'
-require 'active_support/core_ext/module/attribute_accessors'
-require 'active_support/core_ext/module/attribute_accessors_per_thread'
-require 'active_support/core_ext/module/attr_internal'
-require 'active_support/core_ext/module/concerning'
-require 'active_support/core_ext/module/delegation'
-require 'active_support/core_ext/module/deprecation'
-require 'active_support/core_ext/module/remove_method'
-require 'active_support/core_ext/module/qualified_const'
+# frozen_string_literal: true
+
+require "active_support/core_ext/module/aliasing"
+require "active_support/core_ext/module/introspection"
+require "active_support/core_ext/module/anonymous"
+require "active_support/core_ext/module/reachable"
+require "active_support/core_ext/module/attribute_accessors"
+require "active_support/core_ext/module/attribute_accessors_per_thread"
+require "active_support/core_ext/module/attr_internal"
+require "active_support/core_ext/module/concerning"
+require "active_support/core_ext/module/delegation"
+require "active_support/core_ext/module/deprecation"
+require "active_support/core_ext/module/redefine_method"
+require "active_support/core_ext/module/remove_method"
diff --git a/activesupport/lib/active_support/core_ext/module/aliasing.rb b/activesupport/lib/active_support/core_ext/module/aliasing.rb
index b6934b9c54..6f64d11627 100644
--- a/activesupport/lib/active_support/core_ext/module/aliasing.rb
+++ b/activesupport/lib/active_support/core_ext/module/aliasing.rb
@@ -1,52 +1,6 @@
-class Module
-  # NOTE: This method is deprecated. Please use <tt>Module#prepend</tt> that
-  # comes with Ruby 2.0 or newer instead.
-  #
-  # Encapsulates the common pattern of:
-  #
-  #   alias_method :foo_without_feature, :foo
-  #   alias_method :foo, :foo_with_feature
-  #
-  # With this, you simply do:
-  #
-  #   alias_method_chain :foo, :feature
-  #
-  # And both aliases are set up for you.
-  #
-  # Query and bang methods (foo?, foo!) keep the same punctuation:
-  #
-  #   alias_method_chain :foo?, :feature
-  #
-  # is equivalent to
-  #
-  #   alias_method :foo_without_feature?, :foo?
-  #   alias_method :foo?, :foo_with_feature?
-  #
-  # so you can safely chain foo, foo?, foo! and/or foo= with the same feature.
-  def alias_method_chain(target, feature)
-    ActiveSupport::Deprecation.warn("alias_method_chain is deprecated. Please, use Module#prepend instead. From module, you can access the original method using super.")
-
-    # Strip out punctuation on predicates, bang or writer methods since
-    # e.g. target?_without_feature is not a valid method name.
-    aliased_target, punctuation = target.to_s.sub(/([?!=])$/, ''), $1
-    yield(aliased_target, punctuation) if block_given?
-
-    with_method = "#{aliased_target}_with_#{feature}#{punctuation}"
-    without_method = "#{aliased_target}_without_#{feature}#{punctuation}"
-
-    alias_method without_method, target
-    alias_method target, with_method
-
-    case
-    when public_method_defined?(without_method)
-      public target
-    when protected_method_defined?(without_method)
-      protected target
-    when private_method_defined?(without_method)
-      private target
-    end
-  end
+# frozen_string_literal: true
 
+class Module
   # Allows you to make aliases for attributes, which includes
   # getter, setter, and a predicate.
   #
@@ -65,6 +19,9 @@ class Module
   #   e.subject = "Megastars"
   #   e.title    # => "Megastars"
   def alias_attribute(new_name, old_name)
+    # The following reader methods use an explicit `self` receiver in order to
+    # support aliases that start with an uppercase letter. Otherwise, they would
+    # be resolved as constants instead.
     module_eval <<-STR, __FILE__, __LINE__ + 1
       def #{new_name}; self.#{old_name}; end          # def subject; self.title; end
       def #{new_name}?; self.#{old_name}?; end        # def subject?; self.title?; end
diff --git a/activesupport/lib/active_support/core_ext/module/anonymous.rb b/activesupport/lib/active_support/core_ext/module/anonymous.rb
index 510c9a5430..d1c86b8722 100644
--- a/activesupport/lib/active_support/core_ext/module/anonymous.rb
+++ b/activesupport/lib/active_support/core_ext/module/anonymous.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Module
   # A module may or may not have a name.
   #
diff --git a/activesupport/lib/active_support/core_ext/module/attr_internal.rb b/activesupport/lib/active_support/core_ext/module/attr_internal.rb
index 93fb598650..7801f6d181 100644
--- a/activesupport/lib/active_support/core_ext/module/attr_internal.rb
+++ b/activesupport/lib/active_support/core_ext/module/attr_internal.rb
@@ -1,12 +1,14 @@
+# frozen_string_literal: true
+
 class Module
   # Declares an attribute reader backed by an internally-named instance variable.
   def attr_internal_reader(*attrs)
-    attrs.each {|attr_name| attr_internal_define(attr_name, :reader)}
+    attrs.each { |attr_name| attr_internal_define(attr_name, :reader) }
   end
 
   # Declares an attribute writer backed by an internally-named instance variable.
   def attr_internal_writer(*attrs)
-    attrs.each {|attr_name| attr_internal_define(attr_name, :writer)}
+    attrs.each { |attr_name| attr_internal_define(attr_name, :writer) }
   end
 
   # Declares an attribute reader and writer backed by an internally-named instance
@@ -18,7 +20,7 @@ class Module
   alias_method :attr_internal, :attr_internal_accessor
 
   class << self; attr_accessor :attr_internal_naming_format end
-  self.attr_internal_naming_format = '@_%s'
+  self.attr_internal_naming_format = "@_%s"
 
   private
     def attr_internal_ivar_name(attr)
@@ -26,7 +28,7 @@ class Module
     end
 
     def attr_internal_define(attr_name, type)
-      internal_name = attr_internal_ivar_name(attr_name).sub(/\A@/, '')
+      internal_name = attr_internal_ivar_name(attr_name).sub(/\A@/, "")
       # use native attr_* methods as they are faster on some Ruby implementations
       send("attr_#{type}", internal_name)
       attr_name, internal_name = "#{attr_name}=", "#{internal_name}=" if type == :writer
diff --git a/activesupport/lib/active_support/core_ext/module/attribute_accessors.rb b/activesupport/lib/active_support/core_ext/module/attribute_accessors.rb
index 567ac825e9..580baffa2b 100644
--- a/activesupport/lib/active_support/core_ext/module/attribute_accessors.rb
+++ b/activesupport/lib/active_support/core_ext/module/attribute_accessors.rb
@@ -1,4 +1,7 @@
-require 'active_support/core_ext/array/extract_options'
+# frozen_string_literal: true
+
+require "active_support/core_ext/array/extract_options"
+require "active_support/core_ext/regexp"
 
 # Extends the module object with class/module and instance accessors for
 # class/module attributes, just like the native attr* accessors for instance
@@ -6,7 +9,8 @@ require 'active_support/core_ext/array/extract_options'
 class Module
   # Defines a class attribute and creates a class and instance reader methods.
   # The underlying class variable is set to +nil+, if it is not previously
-  # defined.
+  # defined. All class and instance methods created will be public, even if
+  # this method is called with a private or protected access modifier.
   #
   #   module HairColors
   #     mattr_reader :hair_colors
@@ -36,13 +40,10 @@ class Module
   #
   #   Person.new.hair_colors # => NoMethodError
   #
-  #
-  # Also, you can pass a block to set up the attribute with a default value.
+  # You can set a default value for the attribute.
   #
   #   module HairColors
-  #     mattr_reader :hair_colors do
-  #       [:brown, :black, :blonde, :red]
-  #     end
+  #     mattr_reader :hair_colors, default: [:brown, :black, :blonde, :red]
   #   end
   #
   #   class Person
@@ -50,10 +51,9 @@ class Module
   #   end
   #
   #   Person.new.hair_colors # => [:brown, :black, :blonde, :red]
-  def mattr_reader(*syms)
-    options = syms.extract_options!
+  def mattr_reader(*syms, instance_reader: true, instance_accessor: true, default: nil)
     syms.each do |sym|
-      raise NameError.new("invalid attribute name: #{sym}") unless sym =~ /\A[_A-Za-z]\w*\z/
+      raise NameError.new("invalid attribute name: #{sym}") unless /\A[_A-Za-z]\w*\z/.match?(sym)
       class_eval(<<-EOS, __FILE__, __LINE__ + 1)
         @@#{sym} = nil unless defined? @@#{sym}
 
@@ -62,20 +62,24 @@ class Module
         end
       EOS
 
-      unless options[:instance_reader] == false || options[:instance_accessor] == false
+      if instance_reader && instance_accessor
         class_eval(<<-EOS, __FILE__, __LINE__ + 1)
           def #{sym}
             @@#{sym}
           end
         EOS
       end
-      class_variable_set("@@#{sym}", yield) if block_given?
+
+      sym_default_value = (block_given? && default.nil?) ? yield : default
+      class_variable_set("@@#{sym}", sym_default_value) unless sym_default_value.nil?
     end
   end
   alias :cattr_reader :mattr_reader
 
   # Defines a class attribute and creates a class and instance writer methods to
-  # allow assignment to the attribute.
+  # allow assignment to the attribute. All class and instance methods created
+  # will be public, even if this method is called with a private or protected
+  # access modifier.
   #
   #   module HairColors
   #     mattr_writer :hair_colors
@@ -103,12 +107,10 @@ class Module
   #
   #   Person.new.hair_colors = [:blonde, :red] # => NoMethodError
   #
-  # Also, you can pass a block to set up the attribute with a default value.
+  # You can set a default value for the attribute.
   #
   #   module HairColors
-  #     mattr_writer :hair_colors do
-  #       [:brown, :black, :blonde, :red]
-  #     end
+  #     mattr_writer :hair_colors, default: [:brown, :black, :blonde, :red]
   #   end
   #
   #   class Person
@@ -116,10 +118,9 @@ class Module
   #   end
   #
   #   Person.class_variable_get("@@hair_colors") # => [:brown, :black, :blonde, :red]
-  def mattr_writer(*syms)
-    options = syms.extract_options!
+  def mattr_writer(*syms, instance_writer: true, instance_accessor: true, default: nil)
     syms.each do |sym|
-      raise NameError.new("invalid attribute name: #{sym}") unless sym =~ /\A[_A-Za-z]\w*\z/
+      raise NameError.new("invalid attribute name: #{sym}") unless /\A[_A-Za-z]\w*\z/.match?(sym)
       class_eval(<<-EOS, __FILE__, __LINE__ + 1)
         @@#{sym} = nil unless defined? @@#{sym}
 
@@ -128,19 +129,23 @@ class Module
         end
       EOS
 
-      unless options[:instance_writer] == false || options[:instance_accessor] == false
+      if instance_writer && instance_accessor
         class_eval(<<-EOS, __FILE__, __LINE__ + 1)
           def #{sym}=(obj)
             @@#{sym} = obj
           end
         EOS
       end
-      send("#{sym}=", yield) if block_given?
+
+      sym_default_value = (block_given? && default.nil?) ? yield : default
+      send("#{sym}=", sym_default_value) unless sym_default_value.nil?
     end
   end
   alias :cattr_writer :mattr_writer
 
   # Defines both class and instance accessors for class attributes.
+  # All class and instance methods created will be public, even if
+  # this method is called with a private or protected access modifier.
   #
   #   module HairColors
   #     mattr_accessor :hair_colors
@@ -191,12 +196,10 @@ class Module
   #   Person.new.hair_colors = [:brown]  # => NoMethodError
   #   Person.new.hair_colors             # => NoMethodError
   #
-  # Also you can pass a block to set up the attribute with a default value.
+  # You can set a default value for the attribute.
   #
   #   module HairColors
-  #     mattr_accessor :hair_colors do
-  #       [:brown, :black, :blonde, :red]
-  #     end
+  #     mattr_accessor :hair_colors, default: [:brown, :black, :blonde, :red]
   #   end
   #
   #   class Person
@@ -204,9 +207,9 @@ class Module
   #   end
   #
   #   Person.class_variable_get("@@hair_colors") # => [:brown, :black, :blonde, :red]
-  def mattr_accessor(*syms, &blk)
-    mattr_reader(*syms, &blk)
-    mattr_writer(*syms)
+  def mattr_accessor(*syms, instance_reader: true, instance_writer: true, instance_accessor: true, default: nil, &blk)
+    mattr_reader(*syms, instance_reader: instance_reader, instance_accessor: instance_accessor, default: default, &blk)
+    mattr_writer(*syms, instance_writer: instance_writer, instance_accessor: instance_accessor, default: default)
   end
   alias :cattr_accessor :mattr_accessor
 end
diff --git a/activesupport/lib/active_support/core_ext/module/attribute_accessors_per_thread.rb b/activesupport/lib/active_support/core_ext/module/attribute_accessors_per_thread.rb
index 045668c207..4b9b6ea9bd 100644
--- a/activesupport/lib/active_support/core_ext/module/attribute_accessors_per_thread.rb
+++ b/activesupport/lib/active_support/core_ext/module/attribute_accessors_per_thread.rb
@@ -1,9 +1,12 @@
-require 'active_support/core_ext/array/extract_options'
+# frozen_string_literal: true
+
+require "active_support/core_ext/array/extract_options"
+require "active_support/core_ext/regexp"
 
 # Extends the module object with class/module and instance accessors for
 # class/module attributes, just like the native attr* accessors for instance
 # attributes, but does so on a per-thread basis.
-# 
+#
 # So the values are scoped within the Thread.current space under the class name
 # of the module.
 class Module
@@ -33,21 +36,24 @@ class Module
   #   end
   #
   #   Current.new.user # => NoMethodError
-  def thread_mattr_reader(*syms)
+  def thread_mattr_reader(*syms) # :nodoc:
     options = syms.extract_options!
 
     syms.each do |sym|
-      raise NameError.new("invalid attribute name: #{sym}") unless sym =~ /^[_A-Za-z]\w*$/
+      raise NameError.new("invalid attribute name: #{sym}") unless /^[_A-Za-z]\w*$/.match?(sym)
+
+      # The following generated method concatenates `name` because we want it
+      # to work with inheritance via polymorphism.
       class_eval(<<-EOS, __FILE__, __LINE__ + 1)
         def self.#{sym}
-          Thread.current[:"attr_#{name}_#{sym}"]
+          Thread.current["attr_" + name + "_#{sym}"]
         end
       EOS
 
       unless options[:instance_reader] == false || options[:instance_accessor] == false
         class_eval(<<-EOS, __FILE__, __LINE__ + 1)
           def #{sym}
-            Thread.current[:"attr_#{name}_#{sym}"]
+            self.class.#{sym}
           end
         EOS
       end
@@ -73,20 +79,23 @@ class Module
   #   end
   #
   #   Current.new.user = "DHH" # => NoMethodError
-  def thread_mattr_writer(*syms)
+  def thread_mattr_writer(*syms) # :nodoc:
     options = syms.extract_options!
     syms.each do |sym|
-      raise NameError.new("invalid attribute name: #{sym}") unless sym =~ /^[_A-Za-z]\w*$/
+      raise NameError.new("invalid attribute name: #{sym}") unless /^[_A-Za-z]\w*$/.match?(sym)
+
+      # The following generated method concatenates `name` because we want it
+      # to work with inheritance via polymorphism.
       class_eval(<<-EOS, __FILE__, __LINE__ + 1)
         def self.#{sym}=(obj)
-          Thread.current[:"attr_#{name}_#{sym}"] = obj
+          Thread.current["attr_" + name + "_#{sym}"] = obj
         end
       EOS
 
       unless options[:instance_writer] == false || options[:instance_accessor] == false
         class_eval(<<-EOS, __FILE__, __LINE__ + 1)
           def #{sym}=(obj)
-            Thread.current[:"attr_#{name}_#{sym}"] = obj
+            self.class.#{sym} = obj
           end
         EOS
       end
@@ -133,9 +142,9 @@ class Module
   #
   #   Current.new.user = "DHH"  # => NoMethodError
   #   Current.new.user          # => NoMethodError
-  def thread_mattr_accessor(*syms, &blk)
-    thread_mattr_reader(*syms, &blk)
-    thread_mattr_writer(*syms, &blk)
+  def thread_mattr_accessor(*syms)
+    thread_mattr_reader(*syms)
+    thread_mattr_writer(*syms)
   end
   alias :thread_cattr_accessor :thread_mattr_accessor
 end
diff --git a/activesupport/lib/active_support/core_ext/module/concerning.rb b/activesupport/lib/active_support/core_ext/module/concerning.rb
index 65b88b9bbd..7bbbf321ab 100644
--- a/activesupport/lib/active_support/core_ext/module/concerning.rb
+++ b/activesupport/lib/active_support/core_ext/module/concerning.rb
@@ -1,4 +1,6 @@
-require 'active_support/concern'
+# frozen_string_literal: true
+
+require "active_support/concern"
 
 class Module
   # = Bite-sized separation of concerns
@@ -20,7 +22,7 @@ class Module
   #
   # == Using comments:
   #
-  #   class Todo
+  #   class Todo < ApplicationRecord
   #     # Other todo implementation
   #     # ...
   #
@@ -28,7 +30,6 @@ class Module
   #     has_many :events
   #
   #     before_create :track_creation
-  #     after_destroy :track_deletion
   #
   #     private
   #       def track_creation
@@ -40,7 +41,7 @@ class Module
   #
   # Noisy syntax.
   #
-  #   class Todo
+  #   class Todo < ApplicationRecord
   #     # Other todo implementation
   #     # ...
   #
@@ -50,7 +51,6 @@ class Module
   #       included do
   #         has_many :events
   #         before_create :track_creation
-  #         after_destroy :track_deletion
   #       end
   #
   #       private
@@ -68,7 +68,7 @@ class Module
   # increased overhead can be a reasonable tradeoff even if it reduces our
   # at-a-glance perception of how things work.
   #
-  #   class Todo
+  #   class Todo < ApplicationRecord
   #     # Other todo implementation
   #     # ...
   #
@@ -80,7 +80,7 @@ class Module
   # By quieting the mix-in noise, we arrive at a natural, low-ceremony way to
   # separate bite-sized concerns.
   #
-  #   class Todo
+  #   class Todo < ApplicationRecord
   #     # Other todo implementation
   #     # ...
   #
@@ -88,7 +88,6 @@ class Module
   #       included do
   #         has_many :events
   #         before_create :track_creation
-  #         after_destroy :track_deletion
   #       end
   #
   #       private
@@ -99,7 +98,7 @@ class Module
   #   end
   #
   #   Todo.ancestors
-  #   # => [Todo, Todo::EventTracking, Object]
+  #   # => [Todo, Todo::EventTracking, ApplicationRecord, Object]
   #
   # This small step has some wonderful ripple effects. We can
   # * grok the behavior of our class in one glance,
diff --git a/activesupport/lib/active_support/core_ext/module/delegation.rb b/activesupport/lib/active_support/core_ext/module/delegation.rb
index 3f6e8bd26c..4310df3024 100644
--- a/activesupport/lib/active_support/core_ext/module/delegation.rb
+++ b/activesupport/lib/active_support/core_ext/module/delegation.rb
@@ -1,15 +1,19 @@
-require 'set'
+# frozen_string_literal: true
+
+require "set"
+require "active_support/core_ext/regexp"
 
 class Module
   # Error generated by +delegate+ when a method is called on +nil+ and +allow_nil+
   # option is not used.
   class DelegationError < NoMethodError; end
 
+  RUBY_RESERVED_KEYWORDS = %w(alias and BEGIN begin break case class def defined? do
+  else elsif END end ensure false for if in module next nil not or redo rescue retry
+  return self super then true undef unless until when while yield)
+  DELEGATION_RESERVED_KEYWORDS = %w(_ arg args block)
   DELEGATION_RESERVED_METHOD_NAMES = Set.new(
-    %w(_ arg args alias and BEGIN begin block break case class def defined? do
-       else elsif END end ensure false for if in module next nil not or redo
-       rescue retry return self super then true undef unless until when while
-       yield)
+    RUBY_RESERVED_KEYWORDS + DELEGATION_RESERVED_KEYWORDS
   ).freeze
 
   # Provides a +delegate+ class method to easily expose contained objects'
@@ -18,7 +22,8 @@ class Module
   # ==== Options
   # * <tt>:to</tt> - Specifies the target object
   # * <tt>:prefix</tt> - Prefixes the new method with the target name or a custom prefix
-  # * <tt>:allow_nil</tt> - if set to true, prevents a +NoMethodError+ from being raised
+  # * <tt>:allow_nil</tt> - if set to true, prevents a +Module::DelegationError+
+  #   from being raised
   #
   # The macro receives one or more method names (specified as symbols or
   # strings) and the name of the target object via the <tt>:to</tt> option
@@ -110,18 +115,16 @@ class Module
   #   invoice.customer_address # => 'Vimmersvej 13'
   #
   # If the target is +nil+ and does not respond to the delegated method a
-  # +NoMethodError+ is raised, as with any other value. Sometimes, however, it
-  # makes sense to be robust to that situation and that is the purpose of the
-  # <tt>:allow_nil</tt> option: If the target is not +nil+, or it is and
-  # responds to the method, everything works as usual. But if it is +nil+ and
-  # does not respond to the delegated method, +nil+ is returned.
+  # +Module::DelegationError+ is raised. If you wish to instead return +nil+,
+  # use the <tt>:allow_nil</tt> option.
   #
   #   class User < ActiveRecord::Base
   #     has_one :profile
   #     delegate :age, to: :profile
   #   end
   #
-  #   User.new.age # raises NoMethodError: undefined method `age'
+  #   User.new.age
+  #   # => Module::DelegationError: User#age delegated to profile.age, but profile is nil
   #
   # But if not having a profile yet is fine and should not be an error
   # condition:
@@ -150,18 +153,18 @@ class Module
   # The target method must be public, otherwise it will raise +NoMethodError+.
   def delegate(*methods, to: nil, prefix: nil, allow_nil: nil)
     unless to
-      raise ArgumentError, 'Delegation needs a target. Supply an options hash with a :to key as the last argument (e.g. delegate :hello, to: :greeter).'
+      raise ArgumentError, "Delegation needs a target. Supply an options hash with a :to key as the last argument (e.g. delegate :hello, to: :greeter)."
     end
 
-    if prefix == true && to =~ /^[^a-z_]/
-      raise ArgumentError, 'Can only automatically set the delegation prefix when delegating to a method.'
+    if prefix == true && /^[^a-z_]/.match?(to)
+      raise ArgumentError, "Can only automatically set the delegation prefix when delegating to a method."
     end
 
     method_prefix = \
       if prefix
         "#{prefix == true ? to : prefix}_"
       else
-        ''
+        ""
       end
 
     location = caller_locations(1, 1).first
@@ -170,10 +173,10 @@ class Module
     to = to.to_s
     to = "self.#{to}" if DELEGATION_RESERVED_METHOD_NAMES.include?(to)
 
-    methods.each do |method|
+    methods.map do |method|
       # Attribute writer methods only accept one argument. Makes sure []=
       # methods still accept two arguments.
-      definition = (method =~ /[^\]]=$/) ? 'arg' : '*args, &block'
+      definition = /[^\]]=$/.match?(method) ? "arg" : "*args, &block"
 
       # The following generated method calls the target exactly once, storing
       # the returned value in a dummy variable.
@@ -190,7 +193,7 @@ class Module
           "  _.#{method}(#{definition})",
           "end",
         "end"
-        ].join ';'
+        ].join ";"
       else
         exception = %(raise DelegationError, "#{self}##{method_prefix}#{method} delegated to #{to}.#{method}, but #{to} is nil: \#{self.inspect}")
 
@@ -205,7 +208,7 @@ class Module
           "    raise",
           "  end",
           "end"
-        ].join ';'
+        ].join ";"
       end
 
       module_eval(method_def, file, line)
@@ -215,62 +218,68 @@ class Module
   # When building decorators, a common pattern may emerge:
   #
   #   class Partition
-  #     def initialize(first_event)
-  #       @events = [ first_event ]
+  #     def initialize(event)
+  #       @event = event
   #     end
   #
-  #     def people
-  #       if @events.first.detail.people.any?
-  #         @events.collect { |e| Array(e.detail.people) }.flatten.uniq
-  #       else
-  #         @events.collect(&:creator).uniq
-  #       end
+  #     def person
+  #       @event.detail.person || @event.creator
   #     end
   #
   #     private
   #       def respond_to_missing?(name, include_private = false)
-  #         @events.respond_to?(name, include_private)
+  #         @event.respond_to?(name, include_private)
   #       end
   #
   #       def method_missing(method, *args, &block)
-  #         @events.send(method, *args, &block)
+  #         @event.send(method, *args, &block)
   #       end
   #   end
   #
-  # With `Module#delegate_missing_to`, the above is condensed to:
+  # With <tt>Module#delegate_missing_to</tt>, the above is condensed to:
   #
   #   class Partition
-  #     delegate_missing_to :@events
+  #     delegate_missing_to :@event
   #
-  #     def initialize(first_event)
-  #       @events = [ first_event ]
+  #     def initialize(event)
+  #       @event = event
   #     end
   #
-  #     def people
-  #       if @events.first.detail.people.any?
-  #         @events.collect { |e| Array(e.detail.people) }.flatten.uniq
-  #       else
-  #         @events.collect(&:creator).uniq
-  #       end
+  #     def person
+  #       @event.detail.person || @event.creator
   #     end
   #   end
   #
-  # The target can be anything callable withing the object. E.g. instance
-  # variables, methods, constants ant the likes.
+  # The target can be anything callable within the object, e.g. instance
+  # variables, methods, constants, etc.
+  #
+  # The delegated method must be public on the target, otherwise it will
+  # raise +NoMethodError+.
   def delegate_missing_to(target)
     target = target.to_s
     target = "self.#{target}" if DELEGATION_RESERVED_METHOD_NAMES.include?(target)
 
     module_eval <<-RUBY, __FILE__, __LINE__ + 1
       def respond_to_missing?(name, include_private = false)
-        #{target}.respond_to?(name, include_private)
+        # It may look like an oversight, but we deliberately do not pass
+        # +include_private+, because they do not get delegated.
+
+        #{target}.respond_to?(name) || super
       end
 
       def method_missing(method, *args, &block)
         if #{target}.respond_to?(method)
           #{target}.public_send(method, *args, &block)
         else
-          super
+          begin
+            super
+          rescue NoMethodError
+            if #{target}.nil?
+              raise DelegationError, "\#{method} delegated to #{target}, but #{target} is nil"
+            else
+              raise
+            end
+          end
         end
       end
     RUBY
diff --git a/activesupport/lib/active_support/core_ext/module/deprecation.rb b/activesupport/lib/active_support/core_ext/module/deprecation.rb
index f3f2e7f5fc..71c42eb357 100644
--- a/activesupport/lib/active_support/core_ext/module/deprecation.rb
+++ b/activesupport/lib/active_support/core_ext/module/deprecation.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Module
   #   deprecate :foo
   #   deprecate bar: 'message'
diff --git a/activesupport/lib/active_support/core_ext/module/introspection.rb b/activesupport/lib/active_support/core_ext/module/introspection.rb
index fa692e1b0e..c5bb598bd1 100644
--- a/activesupport/lib/active_support/core_ext/module/introspection.rb
+++ b/activesupport/lib/active_support/core_ext/module/introspection.rb
@@ -1,14 +1,18 @@
-require 'active_support/inflector'
+# frozen_string_literal: true
+
+require "active_support/inflector"
 
 class Module
   # Returns the name of the module containing this one.
   #
   #   M::N.parent_name # => "M"
   def parent_name
-    if defined? @parent_name
+    if defined?(@parent_name)
       @parent_name
     else
-      @parent_name = name =~ /::[^:]+\Z/ ? $`.freeze : nil
+      parent_name = name =~ /::[^:]+\Z/ ? $`.freeze : nil
+      @parent_name = parent_name unless frozen?
+      parent_name
     end
   end
 
@@ -46,21 +50,13 @@ class Module
   def parents
     parents = []
     if parent_name
-      parts = parent_name.split('::')
+      parts = parent_name.split("::")
       until parts.empty?
-        parents << ActiveSupport::Inflector.constantize(parts * '::')
+        parents << ActiveSupport::Inflector.constantize(parts * "::")
         parts.pop
       end
     end
     parents << Object unless parents.include? Object
     parents
   end
-
-  def local_constants #:nodoc:
-    ActiveSupport::Deprecation.warn(<<-MSG.squish)
-      Module#local_constants is deprecated and will be removed in Rails 5.1.
-      Use Module#constants(false) instead.
-    MSG
-    constants(false)
-  end
 end
diff --git a/activesupport/lib/active_support/core_ext/module/method_transplanting.rb b/activesupport/lib/active_support/core_ext/module/method_transplanting.rb
deleted file mode 100644
index 1fde3db070..0000000000
--- a/activesupport/lib/active_support/core_ext/module/method_transplanting.rb
+++ /dev/null
@@ -1,3 +0,0 @@
-require 'active_support/deprecation'
-
-ActiveSupport::Deprecation.warn("This file is deprecated and will be removed in Rails 5.1 with no replacement.")
diff --git a/activesupport/lib/active_support/core_ext/module/qualified_const.rb b/activesupport/lib/active_support/core_ext/module/qualified_const.rb
deleted file mode 100644
index 3ea39d4267..0000000000
--- a/activesupport/lib/active_support/core_ext/module/qualified_const.rb
+++ /dev/null
@@ -1,70 +0,0 @@
-require 'active_support/core_ext/string/inflections'
-
-#--
-# Allows code reuse in the methods below without polluting Module.
-#++
-
-module ActiveSupport
-  module QualifiedConstUtils
-    def self.raise_if_absolute(path)
-      raise NameError.new("wrong constant name #$&") if path =~ /\A::[^:]+/
-    end
-
-    def self.names(path)
-      path.split('::')
-    end
-  end
-end
-
-##
-# Extends the API for constants to be able to deal with qualified names. Arguments
-# are assumed to be relative to the receiver.
-#
-#--
-# Qualified names are required to be relative because we are extending existing
-# methods that expect constant names, ie, relative paths of length 1. For example,
-# Object.const_get('::String') raises NameError and so does qualified_const_get.
-#++
-class Module
-  def qualified_const_defined?(path, search_parents=true)
-    ActiveSupport::Deprecation.warn(<<-MESSAGE.squish)
-      Module#qualified_const_defined? is deprecated in favour of the builtin
-      Module#const_defined? and will be removed in Rails 5.1.
-    MESSAGE
-
-    ActiveSupport::QualifiedConstUtils.raise_if_absolute(path)
-
-    ActiveSupport::QualifiedConstUtils.names(path).inject(self) do |mod, name|
-      return unless mod.const_defined?(name, search_parents)
-      mod.const_get(name)
-    end
-    return true
-  end
-
-  def qualified_const_get(path)
-    ActiveSupport::Deprecation.warn(<<-MESSAGE.squish)
-      Module#qualified_const_get is deprecated in favour of the builtin
-      Module#const_get and will be removed in Rails 5.1.
-    MESSAGE
-
-    ActiveSupport::QualifiedConstUtils.raise_if_absolute(path)
-
-    ActiveSupport::QualifiedConstUtils.names(path).inject(self) do |mod, name|
-      mod.const_get(name)
-    end
-  end
-
-  def qualified_const_set(path, value)
-    ActiveSupport::Deprecation.warn(<<-MESSAGE.squish)
-      Module#qualified_const_set is deprecated in favour of the builtin
-      Module#const_set and will be removed in Rails 5.1.
-    MESSAGE
-
-    ActiveSupport::QualifiedConstUtils.raise_if_absolute(path)
-
-    const_name = path.demodulize
-    mod_name = path.deconstantize
-    mod = mod_name.empty? ? self : const_get(mod_name)
-    mod.const_set(const_name, value)
-  end
-end
diff --git a/activesupport/lib/active_support/core_ext/module/reachable.rb b/activesupport/lib/active_support/core_ext/module/reachable.rb
index 5d3d0e9851..e9cbda5245 100644
--- a/activesupport/lib/active_support/core_ext/module/reachable.rb
+++ b/activesupport/lib/active_support/core_ext/module/reachable.rb
@@ -1,8 +1,11 @@
-require 'active_support/core_ext/module/anonymous'
-require 'active_support/core_ext/string/inflections'
+# frozen_string_literal: true
+
+require "active_support/core_ext/module/anonymous"
+require "active_support/core_ext/string/inflections"
 
 class Module
   def reachable? #:nodoc:
     !anonymous? && name.safe_constantize.equal?(self)
   end
+  deprecate :reachable?
 end
diff --git a/activesupport/lib/active_support/core_ext/module/redefine_method.rb b/activesupport/lib/active_support/core_ext/module/redefine_method.rb
new file mode 100644
index 0000000000..a0a6622ca4
--- /dev/null
+++ b/activesupport/lib/active_support/core_ext/module/redefine_method.rb
@@ -0,0 +1,49 @@
+# frozen_string_literal: true
+
+class Module
+  if RUBY_VERSION >= "2.3"
+    # Marks the named method as intended to be redefined, if it exists.
+    # Suppresses the Ruby method redefinition warning. Prefer
+    # #redefine_method where possible.
+    def silence_redefinition_of_method(method)
+      if method_defined?(method) || private_method_defined?(method)
+        # This suppresses the "method redefined" warning; the self-alias
+        # looks odd, but means we don't need to generate a unique name
+        alias_method method, method
+      end
+    end
+  else
+    def silence_redefinition_of_method(method)
+      if method_defined?(method) || private_method_defined?(method)
+        alias_method :__rails_redefine, method
+        remove_method :__rails_redefine
+      end
+    end
+  end
+
+  # Replaces the existing method definition, if there is one, with the passed
+  # block as its body.
+  def redefine_method(method, &block)
+    visibility = method_visibility(method)
+    silence_redefinition_of_method(method)
+    define_method(method, &block)
+    send(visibility, method)
+  end
+
+  # Replaces the existing singleton method definition, if there is one, with
+  # the passed block as its body.
+  def redefine_singleton_method(method, &block)
+    singleton_class.redefine_method(method, &block)
+  end
+
+  def method_visibility(method) # :nodoc:
+    case
+    when private_method_defined?(method)
+      :private
+    when protected_method_defined?(method)
+      :protected
+    else
+      :public
+    end
+  end
+end
diff --git a/activesupport/lib/active_support/core_ext/module/remove_method.rb b/activesupport/lib/active_support/core_ext/module/remove_method.rb
index d5ec16d68a..97eb5f9eca 100644
--- a/activesupport/lib/active_support/core_ext/module/remove_method.rb
+++ b/activesupport/lib/active_support/core_ext/module/remove_method.rb
@@ -1,3 +1,7 @@
+# frozen_string_literal: true
+
+require "active_support/core_ext/module/redefine_method"
+
 class Module
   # Removes the named method, if it exists.
   def remove_possible_method(method)
@@ -8,28 +12,6 @@ class Module
 
   # Removes the named singleton method, if it exists.
   def remove_possible_singleton_method(method)
-    singleton_class.instance_eval do
-      remove_possible_method(method)
-    end
-  end
-
-  # Replaces the existing method definition, if there is one, with the passed
-  # block as its body.
-  def redefine_method(method, &block)
-    visibility = method_visibility(method)
-    remove_possible_method(method)
-    define_method(method, &block)
-    send(visibility, method)
-  end
-
-  def method_visibility(method) # :nodoc:
-    case
-    when private_method_defined?(method)
-      :private
-    when protected_method_defined?(method)
-      :protected
-    else
-      :public
-    end
+    singleton_class.remove_possible_method(method)
   end
 end
diff --git a/activesupport/lib/active_support/core_ext/name_error.rb b/activesupport/lib/active_support/core_ext/name_error.rb
index 6b447d772b..d4f1e01140 100644
--- a/activesupport/lib/active_support/core_ext/name_error.rb
+++ b/activesupport/lib/active_support/core_ext/name_error.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class NameError
   # Extract the name of the missing constant from the exception message.
   #
diff --git a/activesupport/lib/active_support/core_ext/numeric.rb b/activesupport/lib/active_support/core_ext/numeric.rb
index bcdc3eace2..0b04e359f9 100644
--- a/activesupport/lib/active_support/core_ext/numeric.rb
+++ b/activesupport/lib/active_support/core_ext/numeric.rb
@@ -1,4 +1,6 @@
-require 'active_support/core_ext/numeric/bytes'
-require 'active_support/core_ext/numeric/time'
-require 'active_support/core_ext/numeric/inquiry'
-require 'active_support/core_ext/numeric/conversions'
+# frozen_string_literal: true
+
+require "active_support/core_ext/numeric/bytes"
+require "active_support/core_ext/numeric/time"
+require "active_support/core_ext/numeric/inquiry"
+require "active_support/core_ext/numeric/conversions"
diff --git a/activesupport/lib/active_support/core_ext/numeric/bytes.rb b/activesupport/lib/active_support/core_ext/numeric/bytes.rb
index dfbca32474..b002eba406 100644
--- a/activesupport/lib/active_support/core_ext/numeric/bytes.rb
+++ b/activesupport/lib/active_support/core_ext/numeric/bytes.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Numeric
   KILOBYTE = 1024
   MEGABYTE = KILOBYTE * 1024
diff --git a/activesupport/lib/active_support/core_ext/numeric/conversions.rb b/activesupport/lib/active_support/core_ext/numeric/conversions.rb
index 6586a351f8..f6c2713986 100644
--- a/activesupport/lib/active_support/core_ext/numeric/conversions.rb
+++ b/activesupport/lib/active_support/core_ext/numeric/conversions.rb
@@ -1,9 +1,10 @@
-require 'active_support/core_ext/big_decimal/conversions'
-require 'active_support/number_helper'
-require 'active_support/core_ext/module/deprecation'
+# frozen_string_literal: true
 
-module ActiveSupport::NumericWithFormat
+require "active_support/core_ext/big_decimal/conversions"
+require "active_support/number_helper"
+require "active_support/core_ext/module/deprecation"
 
+module ActiveSupport::NumericWithFormat
   # Provides options for converting numbers into formatted strings.
   # Options are provided for phone numbers, currency, percentage,
   # precision, positional notation, file size and pretty printing.
@@ -100,42 +101,36 @@ module ActiveSupport::NumericWithFormat
   #  1234567.to_s(:human, precision: 1,
   #                   separator: ',',
   #                   significant: false)                   # => "1,2 Million"
-  def to_s(*args)
-    format, options = args
-    options ||= {}
-
+  def to_s(format = nil, options = nil)
     case format
+    when nil
+      super()
+    when Integer, String
+      super(format)
     when :phone
-      return ActiveSupport::NumberHelper.number_to_phone(self, options)
+      ActiveSupport::NumberHelper.number_to_phone(self, options || {})
     when :currency
-      return ActiveSupport::NumberHelper.number_to_currency(self, options)
+      ActiveSupport::NumberHelper.number_to_currency(self, options || {})
     when :percentage
-      return ActiveSupport::NumberHelper.number_to_percentage(self, options)
+      ActiveSupport::NumberHelper.number_to_percentage(self, options || {})
     when :delimited
-      return ActiveSupport::NumberHelper.number_to_delimited(self, options)
+      ActiveSupport::NumberHelper.number_to_delimited(self, options || {})
     when :rounded
-      return ActiveSupport::NumberHelper.number_to_rounded(self, options)
+      ActiveSupport::NumberHelper.number_to_rounded(self, options || {})
     when :human
-      return ActiveSupport::NumberHelper.number_to_human(self, options)
+      ActiveSupport::NumberHelper.number_to_human(self, options || {})
     when :human_size
-      return ActiveSupport::NumberHelper.number_to_human_size(self, options)
+      ActiveSupport::NumberHelper.number_to_human_size(self, options || {})
+    when Symbol
+      super()
     else
-      if is_a?(Float) || format.is_a?(Symbol)
-        super()
-      else
-        super
-      end
+      super(format)
     end
   end
-
-  def to_formatted_s(*args)
-    to_s(*args)
-  end
-  deprecate to_formatted_s: :to_s
 end
 
 # Ruby 2.4+ unifies Fixnum & Bignum into Integer.
-if Integer == Fixnum
+if 0.class == Integer
   Integer.prepend ActiveSupport::NumericWithFormat
 else
   Fixnum.prepend ActiveSupport::NumericWithFormat
diff --git a/activesupport/lib/active_support/core_ext/numeric/inquiry.rb b/activesupport/lib/active_support/core_ext/numeric/inquiry.rb
index 7e7ac1b0b2..15334c91f1 100644
--- a/activesupport/lib/active_support/core_ext/numeric/inquiry.rb
+++ b/activesupport/lib/active_support/core_ext/numeric/inquiry.rb
@@ -1,26 +1,28 @@
+# frozen_string_literal: true
+
 unless 1.respond_to?(:positive?) # TODO: Remove this file when we drop support to ruby < 2.3
-class Numeric
-  # Returns true if the number is positive.
-  #
-  #   1.positive?  # => true
-  #   0.positive?  # => false
-  #   -1.positive? # => false
-  def positive?
-    self > 0
-  end
+  class Numeric
+    # Returns true if the number is positive.
+    #
+    #   1.positive?  # => true
+    #   0.positive?  # => false
+    #   -1.positive? # => false
+    def positive?
+      self > 0
+    end
 
-  # Returns true if the number is negative.
-  #
-  #   -1.negative? # => true
-  #   0.negative?  # => false
-  #   1.negative?  # => false
-  def negative?
-    self < 0
+    # Returns true if the number is negative.
+    #
+    #   -1.negative? # => true
+    #   0.negative?  # => false
+    #   1.negative?  # => false
+    def negative?
+      self < 0
+    end
   end
-end
 
-class Complex
-  undef :positive?
-  undef :negative?
-end
+  class Complex
+    undef :positive?
+    undef :negative?
+  end
 end
diff --git a/activesupport/lib/active_support/core_ext/numeric/time.rb b/activesupport/lib/active_support/core_ext/numeric/time.rb
index c6ece22f8d..bc4627f7a2 100644
--- a/activesupport/lib/active_support/core_ext/numeric/time.rb
+++ b/activesupport/lib/active_support/core_ext/numeric/time.rb
@@ -1,25 +1,17 @@
-require 'active_support/duration'
-require 'active_support/core_ext/time/calculations'
-require 'active_support/core_ext/time/acts_like'
-require 'active_support/core_ext/date/calculations'
-require 'active_support/core_ext/date/acts_like'
+# frozen_string_literal: true
+
+require "active_support/duration"
+require "active_support/core_ext/time/calculations"
+require "active_support/core_ext/time/acts_like"
+require "active_support/core_ext/date/calculations"
+require "active_support/core_ext/date/acts_like"
 
 class Numeric
-  # Enables the use of time calculations and declarations, like 45.minutes + 2.hours + 4.years.
-  #
-  # These methods use Time#advance for precise date calculations when using from_now, ago, etc.
-  # as well as adding or subtracting their results from a Time object. For example:
-  #
-  #   # equivalent to Time.current.advance(months: 1)
-  #   1.month.from_now
-  #
-  #   # equivalent to Time.current.advance(years: 2)
-  #   2.years.from_now
+  # Returns a Duration instance matching the number of seconds provided.
   #
-  #   # equivalent to Time.current.advance(months: 4, years: 5)
-  #   (4.months + 5.years).from_now
+  #   2.seconds # => 2 seconds
   def seconds
-    ActiveSupport::Duration.new(self, [[:seconds, self]])
+    ActiveSupport::Duration.seconds(self)
   end
   alias :second :seconds
 
@@ -27,7 +19,7 @@ class Numeric
   #
   #   2.minutes # => 2 minutes
   def minutes
-    ActiveSupport::Duration.new(self * 60, [[:minutes, self]])
+    ActiveSupport::Duration.minutes(self)
   end
   alias :minute :minutes
 
@@ -35,7 +27,7 @@ class Numeric
   #
   #   2.hours # => 2 hours
   def hours
-    ActiveSupport::Duration.new(self * 3600, [[:hours, self]])
+    ActiveSupport::Duration.hours(self)
   end
   alias :hour :hours
 
@@ -43,7 +35,7 @@ class Numeric
   #
   #   2.days # => 2 days
   def days
-    ActiveSupport::Duration.new(self * 24.hours, [[:days, self]])
+    ActiveSupport::Duration.days(self)
   end
   alias :day :days
 
@@ -51,7 +43,7 @@ class Numeric
   #
   #   2.weeks # => 2 weeks
   def weeks
-    ActiveSupport::Duration.new(self * 7.days, [[:weeks, self]])
+    ActiveSupport::Duration.weeks(self)
   end
   alias :week :weeks
 
@@ -59,15 +51,15 @@ class Numeric
   #
   #   2.fortnights # => 4 weeks
   def fortnights
-    ActiveSupport::Duration.new(self * 2.weeks, [[:weeks, self * 2]])
+    ActiveSupport::Duration.weeks(self * 2)
   end
   alias :fortnight :fortnights
 
   # Returns the number of milliseconds equivalent to the seconds provided.
-  # Used with the standard time durations, like 1.hour.in_milliseconds --
-  # so we can feed them to JavaScript functions like getTime().
+  # Used with the standard time durations.
   #
-  #   2.in_milliseconds # => 2_000
+  #   2.in_milliseconds # => 2000
+  #   1.hour.in_milliseconds # => 3600000
   def in_milliseconds
     self * 1000
   end
diff --git a/activesupport/lib/active_support/core_ext/object.rb b/activesupport/lib/active_support/core_ext/object.rb
index f4f9152d6a..efd34cc692 100644
--- a/activesupport/lib/active_support/core_ext/object.rb
+++ b/activesupport/lib/active_support/core_ext/object.rb
@@ -1,14 +1,16 @@
-require 'active_support/core_ext/object/acts_like'
-require 'active_support/core_ext/object/blank'
-require 'active_support/core_ext/object/duplicable'
-require 'active_support/core_ext/object/deep_dup'
-require 'active_support/core_ext/object/try'
-require 'active_support/core_ext/object/inclusion'
+# frozen_string_literal: true
 
-require 'active_support/core_ext/object/conversions'
-require 'active_support/core_ext/object/instance_variables'
+require "active_support/core_ext/object/acts_like"
+require "active_support/core_ext/object/blank"
+require "active_support/core_ext/object/duplicable"
+require "active_support/core_ext/object/deep_dup"
+require "active_support/core_ext/object/try"
+require "active_support/core_ext/object/inclusion"
 
-require 'active_support/core_ext/object/json'
-require 'active_support/core_ext/object/to_param'
-require 'active_support/core_ext/object/to_query'
-require 'active_support/core_ext/object/with_options'
+require "active_support/core_ext/object/conversions"
+require "active_support/core_ext/object/instance_variables"
+
+require "active_support/core_ext/object/json"
+require "active_support/core_ext/object/to_param"
+require "active_support/core_ext/object/to_query"
+require "active_support/core_ext/object/with_options"
diff --git a/activesupport/lib/active_support/core_ext/object/acts_like.rb b/activesupport/lib/active_support/core_ext/object/acts_like.rb
index 3912cc5ace..403ee20e39 100644
--- a/activesupport/lib/active_support/core_ext/object/acts_like.rb
+++ b/activesupport/lib/active_support/core_ext/object/acts_like.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Object
   # A duck-type assistant method. For example, Active Support extends Date
   # to define an <tt>acts_like_date?</tt> method, and extends Time to define
@@ -5,6 +7,15 @@ class Object
   # <tt>x.acts_like?(:date)</tt> to do duck-type-safe comparisons, since classes that
   # we want to act like Time simply need to define an <tt>acts_like_time?</tt> method.
   def acts_like?(duck)
-    respond_to? :"acts_like_#{duck}?"
+    case duck
+    when :time
+      respond_to? :acts_like_time?
+    when :date
+      respond_to? :acts_like_date?
+    when :string
+      respond_to? :acts_like_string?
+    else
+      respond_to? :"acts_like_#{duck}?"
+    end
   end
 end
diff --git a/activesupport/lib/active_support/core_ext/object/blank.rb b/activesupport/lib/active_support/core_ext/object/blank.rb
index cb74bad73e..e42ad852dd 100644
--- a/activesupport/lib/active_support/core_ext/object/blank.rb
+++ b/activesupport/lib/active_support/core_ext/object/blank.rb
@@ -1,3 +1,7 @@
+# frozen_string_literal: true
+
+require "active_support/core_ext/regexp"
+
 class Object
   # An object is blank if it's false, empty, or a whitespace string.
   # For example, +false+, '', '   ', +nil+, [], and {} are all blank.
@@ -115,7 +119,7 @@ class String
     # The regexp that matches blank strings is expensive. For the case of empty
     # strings we can speed up this method (~3.5x) with an empty? call. The
     # penalty for the rest of strings is marginal.
-    empty? || BLANK_RE === self
+    empty? || BLANK_RE.match?(self)
   end
 end
 
diff --git a/activesupport/lib/active_support/core_ext/object/conversions.rb b/activesupport/lib/active_support/core_ext/object/conversions.rb
index 540f7aadb0..624fb8d77c 100644
--- a/activesupport/lib/active_support/core_ext/object/conversions.rb
+++ b/activesupport/lib/active_support/core_ext/object/conversions.rb
@@ -1,4 +1,6 @@
-require 'active_support/core_ext/object/to_param'
-require 'active_support/core_ext/object/to_query'
-require 'active_support/core_ext/array/conversions'
-require 'active_support/core_ext/hash/conversions'
+# frozen_string_literal: true
+
+require "active_support/core_ext/object/to_param"
+require "active_support/core_ext/object/to_query"
+require "active_support/core_ext/array/conversions"
+require "active_support/core_ext/hash/conversions"
diff --git a/activesupport/lib/active_support/core_ext/object/deep_dup.rb b/activesupport/lib/active_support/core_ext/object/deep_dup.rb
index 8dfeed0066..c66c5eb2d9 100644
--- a/activesupport/lib/active_support/core_ext/object/deep_dup.rb
+++ b/activesupport/lib/active_support/core_ext/object/deep_dup.rb
@@ -1,4 +1,6 @@
-require 'active_support/core_ext/object/duplicable'
+# frozen_string_literal: true
+
+require "active_support/core_ext/object/duplicable"
 
 class Object
   # Returns a deep copy of object if it's duplicable. If it's
diff --git a/activesupport/lib/active_support/core_ext/object/duplicable.rb b/activesupport/lib/active_support/core_ext/object/duplicable.rb
index 9bc5ee65ba..9bb99087bc 100644
--- a/activesupport/lib/active_support/core_ext/object/duplicable.rb
+++ b/activesupport/lib/active_support/core_ext/object/duplicable.rb
@@ -1,7 +1,9 @@
+# frozen_string_literal: true
+
 #--
-# Most objects are cloneable, but not all. For example you can't dup +nil+:
+# Most objects are cloneable, but not all. For example you can't dup methods:
 #
-#   nil.dup # => TypeError: can't dup NilClass
+#   method(:puts).dup # => TypeError: allocator undefined for Method
 #
 # Classes may signal their instances are not duplicable removing +dup+/+clone+
 # or raising exceptions from them. So, to dup an arbitrary object you normally
@@ -19,7 +21,7 @@
 class Object
   # Can you safely dup this object?
   #
-  # False for +nil+, +false+, +true+, symbol, number, method objects;
+  # False for method objects;
   # true otherwise.
   def duplicable?
     true
@@ -27,61 +29,87 @@ class Object
 end
 
 class NilClass
-  # +nil+ is not duplicable:
-  #
-  #   nil.duplicable? # => false
-  #   nil.dup         # => TypeError: can't dup NilClass
-  def duplicable?
-    false
+  begin
+    nil.dup
+  rescue TypeError
+
+    # +nil+ is not duplicable:
+    #
+    #   nil.duplicable? # => false
+    #   nil.dup         # => TypeError: can't dup NilClass
+    def duplicable?
+      false
+    end
   end
 end
 
 class FalseClass
-  # +false+ is not duplicable:
-  #
-  #   false.duplicable? # => false
-  #   false.dup         # => TypeError: can't dup FalseClass
-  def duplicable?
-    false
+  begin
+    false.dup
+  rescue TypeError
+
+    # +false+ is not duplicable:
+    #
+    #   false.duplicable? # => false
+    #   false.dup         # => TypeError: can't dup FalseClass
+    def duplicable?
+      false
+    end
   end
 end
 
 class TrueClass
-  # +true+ is not duplicable:
-  #
-  #   true.duplicable? # => false
-  #   true.dup         # => TypeError: can't dup TrueClass
-  def duplicable?
-    false
+  begin
+    true.dup
+  rescue TypeError
+
+    # +true+ is not duplicable:
+    #
+    #   true.duplicable? # => false
+    #   true.dup         # => TypeError: can't dup TrueClass
+    def duplicable?
+      false
+    end
   end
 end
 
 class Symbol
-  # Symbols are not duplicable:
-  #
-  #   :my_symbol.duplicable? # => false
-  #   :my_symbol.dup         # => TypeError: can't dup Symbol
-  def duplicable?
-    false
+  begin
+    :symbol.dup # Ruby 2.4.x.
+    "symbol_from_string".to_sym.dup # Some symbols can't `dup` in Ruby 2.4.0.
+  rescue TypeError
+
+    # Symbols are not duplicable:
+    #
+    #   :my_symbol.duplicable? # => false
+    #   :my_symbol.dup         # => TypeError: can't dup Symbol
+    def duplicable?
+      false
+    end
   end
 end
 
 class Numeric
-  # Numbers are not duplicable:
-  #
-  #  3.duplicable? # => false
-  #  3.dup         # => TypeError: can't dup Integer
-  def duplicable?
-    false
+  begin
+    1.dup
+  rescue TypeError
+
+    # Numbers are not duplicable:
+    #
+    #  3.duplicable? # => false
+    #  3.dup         # => TypeError: can't dup Integer
+    def duplicable?
+      false
+    end
   end
 end
 
-require 'bigdecimal'
+require "bigdecimal"
 class BigDecimal
   # BigDecimals are duplicable:
   #
-  # BigDecimal.new("1.2").duplicable? # => true
-  # BigDecimal.new("1.2").dup         # => #<BigDecimal:...,'0.12E1',18(18)>
+  #   BigDecimal("1.2").duplicable? # => true
+  #   BigDecimal("1.2").dup         # => #<BigDecimal:...,'0.12E1',18(18)>
   def duplicable?
     true
   end
@@ -96,3 +124,33 @@ class Method
     false
   end
 end
+
+class Complex
+  begin
+    Complex(1).dup
+  rescue TypeError
+
+    # Complexes are not duplicable:
+    #
+    #   Complex(1).duplicable? # => false
+    #   Complex(1).dup         # => TypeError: can't copy Complex
+    def duplicable?
+      false
+    end
+  end
+end
+
+class Rational
+  begin
+    Rational(1).dup
+  rescue TypeError
+
+    # Rationals are not duplicable:
+    #
+    #   Rational(1).duplicable? # => false
+    #   Rational(1).dup         # => TypeError: can't copy Rational
+    def duplicable?
+      false
+    end
+  end
+end
diff --git a/activesupport/lib/active_support/core_ext/object/inclusion.rb b/activesupport/lib/active_support/core_ext/object/inclusion.rb
index d4c17dfb07..6064e92f20 100644
--- a/activesupport/lib/active_support/core_ext/object/inclusion.rb
+++ b/activesupport/lib/active_support/core_ext/object/inclusion.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Object
   # Returns true if this object is included in the argument. Argument must be
   # any object which responds to +#include?+. Usage:
@@ -22,6 +24,6 @@ class Object
   #
   # @return [Object]
   def presence_in(another_object)
-    self.in?(another_object) ? self : nil
+    in?(another_object) ? self : nil
   end
 end
diff --git a/activesupport/lib/active_support/core_ext/object/instance_variables.rb b/activesupport/lib/active_support/core_ext/object/instance_variables.rb
index 593a7a4940..12fdf840b5 100644
--- a/activesupport/lib/active_support/core_ext/object/instance_variables.rb
+++ b/activesupport/lib/active_support/core_ext/object/instance_variables.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Object
   # Returns a hash with string keys that maps instance variable names without "@" to their
   # corresponding values.
diff --git a/activesupport/lib/active_support/core_ext/object/json.rb b/activesupport/lib/active_support/core_ext/object/json.rb
index d49b2fbe54..f7c623fe13 100644
--- a/activesupport/lib/active_support/core_ext/object/json.rb
+++ b/activesupport/lib/active_support/core_ext/object/json.rb
@@ -1,14 +1,18 @@
+# frozen_string_literal: true
+
 # Hack to load json gem first so we can overwrite its to_json.
-require 'json'
-require 'bigdecimal'
-require 'active_support/core_ext/big_decimal/conversions' # for #to_s
-require 'active_support/core_ext/hash/except'
-require 'active_support/core_ext/hash/slice'
-require 'active_support/core_ext/object/instance_variables'
-require 'time'
-require 'active_support/core_ext/time/conversions'
-require 'active_support/core_ext/date_time/conversions'
-require 'active_support/core_ext/date/conversions'
+require "json"
+require "bigdecimal"
+require "uri/generic"
+require "pathname"
+require "active_support/core_ext/big_decimal/conversions" # for #to_s
+require "active_support/core_ext/hash/except"
+require "active_support/core_ext/hash/slice"
+require "active_support/core_ext/object/instance_variables"
+require "time"
+require "active_support/core_ext/time/conversions"
+require "active_support/core_ext/date_time/conversions"
+require "active_support/core_ext/date/conversions"
 
 # The JSON gem adds a few modules to Ruby core classes containing :to_json definition, overwriting
 # their default behavior. That said, we need to define the basic to_json method in all of them,
@@ -131,6 +135,12 @@ module Enumerable
   end
 end
 
+class IO
+  def as_json(options = nil) #:nodoc:
+    to_s
+  end
+end
+
 class Range
   def as_json(options = nil) #:nodoc:
     to_s
@@ -187,14 +197,26 @@ class DateTime
     if ActiveSupport::JSON::Encoding.use_standard_json_time_format
       xmlschema(ActiveSupport::JSON::Encoding.time_precision)
     else
-      strftime('%Y/%m/%d %H:%M:%S %z')
+      strftime("%Y/%m/%d %H:%M:%S %z")
     end
   end
 end
 
+class URI::Generic #:nodoc:
+  def as_json(options = nil)
+    to_s
+  end
+end
+
+class Pathname #:nodoc:
+  def as_json(options = nil)
+    to_s
+  end
+end
+
 class Process::Status #:nodoc:
   def as_json(options = nil)
-    { :exitstatus => exitstatus, :pid => pid }
+    { exitstatus: exitstatus, pid: pid }
   end
 end
 
diff --git a/activesupport/lib/active_support/core_ext/object/to_param.rb b/activesupport/lib/active_support/core_ext/object/to_param.rb
index 684d4ef57e..6d2bdd70f3 100644
--- a/activesupport/lib/active_support/core_ext/object/to_param.rb
+++ b/activesupport/lib/active_support/core_ext/object/to_param.rb
@@ -1 +1,3 @@
-require 'active_support/core_ext/object/to_query'
+# frozen_string_literal: true
+
+require "active_support/core_ext/object/to_query"
diff --git a/activesupport/lib/active_support/core_ext/object/to_query.rb b/activesupport/lib/active_support/core_ext/object/to_query.rb
index ec5ace4e16..abb461966a 100644
--- a/activesupport/lib/active_support/core_ext/object/to_query.rb
+++ b/activesupport/lib/active_support/core_ext/object/to_query.rb
@@ -1,4 +1,6 @@
-require 'cgi'
+# frozen_string_literal: true
+
+require "cgi"
 
 class Object
   # Alias of <tt>to_s</tt>.
@@ -38,7 +40,7 @@ class Array
   # Calls <tt>to_param</tt> on all its elements and joins the result with
   # slashes. This is used by <tt>url_for</tt> in Action Pack.
   def to_param
-    collect(&:to_param).join '/'
+    collect(&:to_param).join "/"
   end
 
   # Converts an array into a string suitable for use as a URL query string,
@@ -51,7 +53,7 @@ class Array
     if empty?
       nil.to_query(prefix)
     else
-      collect { |value| value.to_query(prefix) }.join '&'
+      collect { |value| value.to_query(prefix) }.join "&"
     end
   end
 end
@@ -77,7 +79,7 @@ class Hash
       unless (value.is_a?(Hash) || value.is_a?(Array)) && value.empty?
         value.to_query(namespace ? "#{namespace}[#{key}]" : key)
       end
-    end.compact.sort! * '&'
+    end.compact.sort! * "&"
   end
 
   alias_method :to_param, :to_query
diff --git a/activesupport/lib/active_support/core_ext/object/try.rb b/activesupport/lib/active_support/core_ext/object/try.rb
index 3b6d9da216..c874691629 100644
--- a/activesupport/lib/active_support/core_ext/object/try.rb
+++ b/activesupport/lib/active_support/core_ext/object/try.rb
@@ -1,4 +1,6 @@
-require 'delegate'
+# frozen_string_literal: true
+
+require "delegate"
 
 module ActiveSupport
   module Tryable #:nodoc:
diff --git a/activesupport/lib/active_support/core_ext/object/with_options.rb b/activesupport/lib/active_support/core_ext/object/with_options.rb
index 513c8b1d55..2838fd76be 100644
--- a/activesupport/lib/active_support/core_ext/object/with_options.rb
+++ b/activesupport/lib/active_support/core_ext/object/with_options.rb
@@ -1,4 +1,6 @@
-require 'active_support/option_merger'
+# frozen_string_literal: true
+
+require "active_support/option_merger"
 
 class Object
   # An elegant way to factor duplication out of options passed to a series of
@@ -60,7 +62,18 @@ class Object
   #
   #   validates :content, length: { minimum: 50 }, if: -> { content.present? }
   #
-  # Hence the inherited default for `if` key is ignored.
+  # Hence the inherited default for +if+ key is ignored.
+  #
+  # NOTE: You cannot call class methods implicitly inside of with_options.
+  # You can access these methods using the class name instead:
+  #
+  #   class Phone < ActiveRecord::Base
+  #     enum phone_number_type: [home: 0, office: 1, mobile: 2]
+  #
+  #     with_options presence: true do
+  #       validates :phone_number_type, inclusion: { in: Phone.phone_number_types.keys }
+  #     end
+  #   end
   #
   def with_options(options, &block)
     option_merger = ActiveSupport::OptionMerger.new(self, options)
diff --git a/activesupport/lib/active_support/core_ext/range.rb b/activesupport/lib/active_support/core_ext/range.rb
index 9368e81235..4074e91d17 100644
--- a/activesupport/lib/active_support/core_ext/range.rb
+++ b/activesupport/lib/active_support/core_ext/range.rb
@@ -1,4 +1,7 @@
-require 'active_support/core_ext/range/conversions'
-require 'active_support/core_ext/range/include_range'
-require 'active_support/core_ext/range/overlaps'
-require 'active_support/core_ext/range/each'
+# frozen_string_literal: true
+
+require "active_support/core_ext/range/conversions"
+require "active_support/core_ext/range/include_range"
+require "active_support/core_ext/range/include_time_with_zone"
+require "active_support/core_ext/range/overlaps"
+require "active_support/core_ext/range/each"
diff --git a/activesupport/lib/active_support/core_ext/range/conversions.rb b/activesupport/lib/active_support/core_ext/range/conversions.rb
index 965436c23a..8832fbcb3c 100644
--- a/activesupport/lib/active_support/core_ext/range/conversions.rb
+++ b/activesupport/lib/active_support/core_ext/range/conversions.rb
@@ -1,6 +1,14 @@
+# frozen_string_literal: true
+
 module ActiveSupport::RangeWithFormat
   RANGE_FORMATS = {
-    :db => Proc.new { |start, stop| "BETWEEN '#{start.to_s(:db)}' AND '#{stop.to_s(:db)}'" }
+    db: -> (start, stop) do
+      case start
+      when String then "BETWEEN '#{start}' AND '#{stop}'"
+      else
+        "BETWEEN '#{start.to_s(:db)}' AND '#{stop.to_s(:db)}'"
+      end
+    end
   }
 
   # Convert range to a formatted string. See RANGE_FORMATS for predefined formats.
diff --git a/activesupport/lib/active_support/core_ext/range/each.rb b/activesupport/lib/active_support/core_ext/range/each.rb
index dc6dad5ced..2f22cd0e92 100644
--- a/activesupport/lib/active_support/core_ext/range/each.rb
+++ b/activesupport/lib/active_support/core_ext/range/each.rb
@@ -1,3 +1,7 @@
+# frozen_string_literal: true
+
+require "active_support/time_with_zone"
+
 module ActiveSupport
   module EachTimeWithZone #:nodoc:
     def each(&block)
@@ -13,7 +17,7 @@ module ActiveSupport
     private
 
       def ensure_iteration_allowed
-        raise TypeError, "can't iterate from #{first.class}" if first.is_a?(Time)
+        raise TypeError, "can't iterate from #{first.class}" if first.is_a?(TimeWithZone)
       end
   end
 end
diff --git a/activesupport/lib/active_support/core_ext/range/include_range.rb b/activesupport/lib/active_support/core_ext/range/include_range.rb
index c69e1e3fb9..7ba1011921 100644
--- a/activesupport/lib/active_support/core_ext/range/include_range.rb
+++ b/activesupport/lib/active_support/core_ext/range/include_range.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActiveSupport
   module IncludeWithRange #:nodoc:
     # Extends the default Range#include? to support range comparisons.
diff --git a/activesupport/lib/active_support/core_ext/range/include_time_with_zone.rb b/activesupport/lib/active_support/core_ext/range/include_time_with_zone.rb
new file mode 100644
index 0000000000..5f80acf68e
--- /dev/null
+++ b/activesupport/lib/active_support/core_ext/range/include_time_with_zone.rb
@@ -0,0 +1,23 @@
+# frozen_string_literal: true
+
+require "active_support/time_with_zone"
+
+module ActiveSupport
+  module IncludeTimeWithZone #:nodoc:
+    # Extends the default Range#include? to support ActiveSupport::TimeWithZone.
+    #
+    #   (1.hour.ago..1.hour.from_now).include?(Time.current) # => true
+    #
+    def include?(value)
+      if first.is_a?(TimeWithZone)
+        cover?(value)
+      elsif last.is_a?(TimeWithZone)
+        cover?(value)
+      else
+        super
+      end
+    end
+  end
+end
+
+Range.prepend(ActiveSupport::IncludeTimeWithZone)
diff --git a/activesupport/lib/active_support/core_ext/range/overlaps.rb b/activesupport/lib/active_support/core_ext/range/overlaps.rb
index 603657c180..f753607f8b 100644
--- a/activesupport/lib/active_support/core_ext/range/overlaps.rb
+++ b/activesupport/lib/active_support/core_ext/range/overlaps.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Range
   # Compare two ranges and see if they overlap each other
   #  (1..5).overlaps?(4..6) # => true
diff --git a/activesupport/lib/active_support/core_ext/regexp.rb b/activesupport/lib/active_support/core_ext/regexp.rb
index 784145f5fb..efbd708aee 100644
--- a/activesupport/lib/active_support/core_ext/regexp.rb
+++ b/activesupport/lib/active_support/core_ext/regexp.rb
@@ -1,5 +1,11 @@
+# frozen_string_literal: true
+
 class Regexp #:nodoc:
   def multiline?
     options & MULTILINE == MULTILINE
   end
+
+  def match?(string, pos = 0)
+    !!match(string, pos)
+  end unless //.respond_to?(:match?)
 end
diff --git a/activesupport/lib/active_support/core_ext/securerandom.rb b/activesupport/lib/active_support/core_ext/securerandom.rb
index 98cf7430f7..b4a491f5fd 100644
--- a/activesupport/lib/active_support/core_ext/securerandom.rb
+++ b/activesupport/lib/active_support/core_ext/securerandom.rb
@@ -1,12 +1,14 @@
-require 'securerandom'
+# frozen_string_literal: true
+
+require "securerandom"
 
 module SecureRandom
-  BASE58_ALPHABET = ('0'..'9').to_a  + ('A'..'Z').to_a + ('a'..'z').to_a - ['0', 'O', 'I', 'l']
+  BASE58_ALPHABET = ("0".."9").to_a + ("A".."Z").to_a + ("a".."z").to_a - ["0", "O", "I", "l"]
   # SecureRandom.base58 generates a random base58 string.
   #
   # The argument _n_ specifies the length, of the random string to be generated.
   #
-  # If _n_ is not specified or is nil, 16 is assumed. It may be larger in the future.
+  # If _n_ is not specified or is +nil+, 16 is assumed. It may be larger in the future.
   #
   # The result may contain alphanumeric characters except 0, O, I and l
   #
diff --git a/activesupport/lib/active_support/core_ext/string.rb b/activesupport/lib/active_support/core_ext/string.rb
index c656db2c6c..757d15c51a 100644
--- a/activesupport/lib/active_support/core_ext/string.rb
+++ b/activesupport/lib/active_support/core_ext/string.rb
@@ -1,13 +1,15 @@
-require 'active_support/core_ext/string/conversions'
-require 'active_support/core_ext/string/filters'
-require 'active_support/core_ext/string/multibyte'
-require 'active_support/core_ext/string/starts_ends_with'
-require 'active_support/core_ext/string/inflections'
-require 'active_support/core_ext/string/access'
-require 'active_support/core_ext/string/behavior'
-require 'active_support/core_ext/string/output_safety'
-require 'active_support/core_ext/string/exclude'
-require 'active_support/core_ext/string/strip'
-require 'active_support/core_ext/string/inquiry'
-require 'active_support/core_ext/string/indent'
-require 'active_support/core_ext/string/zones'
+# frozen_string_literal: true
+
+require "active_support/core_ext/string/conversions"
+require "active_support/core_ext/string/filters"
+require "active_support/core_ext/string/multibyte"
+require "active_support/core_ext/string/starts_ends_with"
+require "active_support/core_ext/string/inflections"
+require "active_support/core_ext/string/access"
+require "active_support/core_ext/string/behavior"
+require "active_support/core_ext/string/output_safety"
+require "active_support/core_ext/string/exclude"
+require "active_support/core_ext/string/strip"
+require "active_support/core_ext/string/inquiry"
+require "active_support/core_ext/string/indent"
+require "active_support/core_ext/string/zones"
diff --git a/activesupport/lib/active_support/core_ext/string/access.rb b/activesupport/lib/active_support/core_ext/string/access.rb
index 213a91aa7a..58591bbaaf 100644
--- a/activesupport/lib/active_support/core_ext/string/access.rb
+++ b/activesupport/lib/active_support/core_ext/string/access.rb
@@ -1,9 +1,11 @@
+# frozen_string_literal: true
+
 class String
   # If you pass a single integer, returns a substring of one character at that
   # position. The first character of the string is at position 0, the next at
   # position 1, and so on. If a range is supplied, a substring containing
   # characters at offsets given by the range is returned. In both cases, if an
-  # offset is negative, it is counted from the end of the string. Returns nil
+  # offset is negative, it is counted from the end of the string. Returns +nil+
   # if the initial offset falls outside the string. Returns an empty string if
   # the beginning of the range is greater than the end of the string.
   #
@@ -17,7 +19,7 @@ class String
   #
   # If a Regexp is given, the matching portion of the string is returned.
   # If a String is given, that given string is returned if it occurs in
-  # the string. In both cases, nil is returned if there is no match.
+  # the string. In both cases, +nil+ is returned if there is no match.
   #
   #   str = "hello"
   #   str.at(/lo/) # => "lo"
@@ -74,9 +76,9 @@ class String
   #   str.first(6) # => "hello"
   def first(limit = 1)
     if limit == 0
-      ''
+      ""
     elsif limit >= size
-      self.dup
+      dup
     else
       to(limit - 1)
     end
@@ -94,9 +96,9 @@ class String
   #   str.last(6) # => "hello"
   def last(limit = 1)
     if limit == 0
-      ''
+      ""
     elsif limit >= size
-      self.dup
+      dup
     else
       from(-limit)
     end
diff --git a/activesupport/lib/active_support/core_ext/string/behavior.rb b/activesupport/lib/active_support/core_ext/string/behavior.rb
index 710f1f4670..35a5aa7840 100644
--- a/activesupport/lib/active_support/core_ext/string/behavior.rb
+++ b/activesupport/lib/active_support/core_ext/string/behavior.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class String
   # Enables more predictable duck-typing on String-like classes. See <tt>Object#acts_like?</tt>.
   def acts_like_string?
diff --git a/activesupport/lib/active_support/core_ext/string/conversions.rb b/activesupport/lib/active_support/core_ext/string/conversions.rb
index 946976c5e9..29a88b07ad 100644
--- a/activesupport/lib/active_support/core_ext/string/conversions.rb
+++ b/activesupport/lib/active_support/core_ext/string/conversions.rb
@@ -1,5 +1,7 @@
-require 'date'
-require 'active_support/core_ext/time/calculations'
+# frozen_string_literal: true
+
+require "date"
+require "active_support/core_ext/time/calculations"
 
 class String
   # Converts a string to a Time value.
diff --git a/activesupport/lib/active_support/core_ext/string/exclude.rb b/activesupport/lib/active_support/core_ext/string/exclude.rb
index 0ac684f6ee..8e462689f1 100644
--- a/activesupport/lib/active_support/core_ext/string/exclude.rb
+++ b/activesupport/lib/active_support/core_ext/string/exclude.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class String
   # The inverse of <tt>String#include?</tt>. Returns true if the string
   # does not include the other string.
diff --git a/activesupport/lib/active_support/core_ext/string/filters.rb b/activesupport/lib/active_support/core_ext/string/filters.rb
index 375ec1aef8..66e721eea3 100644
--- a/activesupport/lib/active_support/core_ext/string/filters.rb
+++ b/activesupport/lib/active_support/core_ext/string/filters.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class String
   # Returns the string, first removing all whitespace on both ends of
   # the string, and then changing remaining consecutive whitespace
@@ -17,7 +19,7 @@ class String
   #   str.squish!                         # => "foo bar boo"
   #   str                                 # => "foo bar boo"
   def squish!
-    gsub!(/[[:space:]]+/, ' ')
+    gsub!(/[[:space:]]+/, " ")
     strip!
     self
   end
@@ -64,7 +66,7 @@ class String
   def truncate(truncate_at, options = {})
     return dup unless length > truncate_at
 
-    omission = options[:omission] || '...'
+    omission = options[:omission] || "..."
     length_with_room_for_omission = truncate_at - omission.length
     stop = \
       if options[:separator]
@@ -94,7 +96,7 @@ class String
     sep = options[:separator] || /\s+/
     sep = Regexp.escape(sep.to_s) unless Regexp === sep
     if self =~ /\A((?>.+?#{sep}){#{words_count - 1}}.+?)#{sep}.*/m
-      $1 + (options[:omission] || '...')
+      $1 + (options[:omission] || "...")
     else
       dup
     end
diff --git a/activesupport/lib/active_support/core_ext/string/indent.rb b/activesupport/lib/active_support/core_ext/string/indent.rb
index ce3a69cf5f..af9d181487 100644
--- a/activesupport/lib/active_support/core_ext/string/indent.rb
+++ b/activesupport/lib/active_support/core_ext/string/indent.rb
@@ -1,9 +1,11 @@
+# frozen_string_literal: true
+
 class String
   # Same as +indent+, except it indents the receiver in-place.
   #
   # Returns the indented string, or +nil+ if there was nothing to indent.
-  def indent!(amount, indent_string=nil, indent_empty_lines=false)
-    indent_string = indent_string || self[/^[ \t]/] || ' '
+  def indent!(amount, indent_string = nil, indent_empty_lines = false)
+    indent_string = indent_string || self[/^[ \t]/] || " "
     re = indent_empty_lines ? /^/ : /^(?!$)/
     gsub!(re, indent_string * amount)
   end
@@ -37,7 +39,7 @@ class String
   #   "foo\n\nbar".indent(2)            # => "  foo\n\n  bar"
   #   "foo\n\nbar".indent(2, nil, true) # => "  foo\n  \n  bar"
   #
-  def indent(amount, indent_string=nil, indent_empty_lines=false)
-    dup.tap {|_| _.indent!(amount, indent_string, indent_empty_lines)}
+  def indent(amount, indent_string = nil, indent_empty_lines = false)
+    dup.tap { |_| _.indent!(amount, indent_string, indent_empty_lines) }
   end
 end
diff --git a/activesupport/lib/active_support/core_ext/string/inflections.rb b/activesupport/lib/active_support/core_ext/string/inflections.rb
index 7277f51076..8af301734a 100644
--- a/activesupport/lib/active_support/core_ext/string/inflections.rb
+++ b/activesupport/lib/active_support/core_ext/string/inflections.rb
@@ -1,5 +1,7 @@
-require 'active_support/inflector/methods'
-require 'active_support/inflector/transliterate'
+# frozen_string_literal: true
+
+require "active_support/inflector/methods"
+require "active_support/inflector/transliterate"
 
 # String inflections define new methods on the String class to transform names for different purposes.
 # For instance, you can figure out the name of a table from the name of a class.
@@ -31,7 +33,7 @@ class String
   def pluralize(count = nil, locale = :en)
     locale = count if count.is_a?(Symbol)
     if count == 1
-      self.dup
+      dup
     else
       ActiveSupport::Inflector.pluralize(self, locale)
     end
@@ -67,7 +69,7 @@ class String
   end
 
   # +safe_constantize+ tries to find a declared constant with the name specified
-  # in the string. It returns nil when the name is not in CamelCase
+  # in the string. It returns +nil+ when the name is not in CamelCase
   # or is not initialized.  See ActiveSupport::Inflector.safe_constantize
   #
   #   'Module'.safe_constantize  # => Module
@@ -92,6 +94,8 @@ class String
       ActiveSupport::Inflector.camelize(self, true)
     when :lower
       ActiveSupport::Inflector.camelize(self, false)
+    else
+      raise ArgumentError, "Invalid option, use either :upper or :lower."
     end
   end
   alias_method :camelcase, :camelize
@@ -100,12 +104,17 @@ class String
   # a nicer looking title. +titleize+ is meant for creating pretty output. It is not
   # used in the Rails internals.
   #
+  # The trailing '_id','Id'.. can be kept and capitalized by setting the
+  # optional parameter +keep_id_suffix+ to true.
+  # By default, this parameter is false.
+  #
   # +titleize+ is also aliased as +titlecase+.
   #
-  #   'man from the boondocks'.titleize # => "Man From The Boondocks"
-  #   'x-men: the last stand'.titleize  # => "X Men: The Last Stand"
-  def titleize
-    ActiveSupport::Inflector.titleize(self)
+  #   'man from the boondocks'.titleize                       # => "Man From The Boondocks"
+  #   'x-men: the last stand'.titleize                        # => "X Men: The Last Stand"
+  #   'string_ending_with_id'.titleize(keep_id_suffix: true)  # => "String Ending With Id"
+  def titleize(keep_id_suffix: false)
+    ActiveSupport::Inflector.titleize(self, keep_id_suffix: keep_id_suffix)
   end
   alias_method :titlecase, :titleize
 
@@ -128,10 +137,10 @@ class String
 
   # Removes the module part from the constant expression in the string.
   #
-  #   'ActiveRecord::CoreExtensions::String::Inflections'.demodulize # => "Inflections"
-  #   'Inflections'.demodulize                                       # => "Inflections"
-  #   '::Inflections'.demodulize                                     # => "Inflections"
-  #   ''.demodulize                                                  # => ''
+  #   'ActiveSupport::Inflector::Inflections'.demodulize # => "Inflections"
+  #   'Inflections'.demodulize                           # => "Inflections"
+  #   '::Inflections'.demodulize                         # => "Inflections"
+  #   ''.demodulize                                      # => ''
   #
   # See also +deconstantize+.
   def demodulize
@@ -164,8 +173,8 @@ class String
   #
   #   <%= link_to(@person.name, person_path) %>
   #   # => <a href="/person/1-donald-e-knuth">Donald E. Knuth</a>
-  #   
-  # To preserve the case of the characters in a string, use the `preserve_case` argument.
+  #
+  # To preserve the case of the characters in a string, use the +preserve_case+ argument.
   #
   #   class Person
   #     def to_param
@@ -178,11 +187,7 @@ class String
   #
   #   <%= link_to(@person.name, person_path) %>
   #   # => <a href="/person/1-Donald-E-Knuth">Donald E. Knuth</a>
-  def parameterize(sep = :unused, separator: '-', preserve_case: false)
-    unless sep == :unused
-      ActiveSupport::Deprecation.warn("Passing the separator argument as a positional parameter is deprecated and will soon be removed. Use `separator: '#{sep}'` instead.")
-      separator = sep
-    end
+  def parameterize(separator: "-", preserve_case: false)
     ActiveSupport::Inflector.parameterize(self, separator: separator, preserve_case: preserve_case)
   end
 
@@ -206,7 +211,7 @@ class String
     ActiveSupport::Inflector.classify(self)
   end
 
-  # Capitalizes the first word, turns underscores into spaces, and strips a
+  # Capitalizes the first word, turns underscores into spaces, and (by default)strips a
   # trailing '_id' if present.
   # Like +titleize+, this is meant for creating pretty output.
   #
@@ -214,12 +219,17 @@ class String
   # optional parameter +capitalize+ to false.
   # By default, this parameter is true.
   #
-  #   'employee_salary'.humanize              # => "Employee salary"
-  #   'author_id'.humanize                    # => "Author"
-  #   'author_id'.humanize(capitalize: false) # => "author"
-  #   '_id'.humanize                          # => "Id"
-  def humanize(options = {})
-    ActiveSupport::Inflector.humanize(self, options)
+  # The trailing '_id' can be kept and capitalized by setting the
+  # optional parameter +keep_id_suffix+ to true.
+  # By default, this parameter is false.
+  #
+  #   'employee_salary'.humanize                    # => "Employee salary"
+  #   'author_id'.humanize                          # => "Author"
+  #   'author_id'.humanize(capitalize: false)       # => "author"
+  #   '_id'.humanize                                # => "Id"
+  #   'author_id'.humanize(keep_id_suffix: true)    # => "Author Id"
+  def humanize(capitalize: true, keep_id_suffix: false)
+    ActiveSupport::Inflector.humanize(self, capitalize: capitalize, keep_id_suffix: keep_id_suffix)
   end
 
   # Converts just the first character to uppercase.
diff --git a/activesupport/lib/active_support/core_ext/string/inquiry.rb b/activesupport/lib/active_support/core_ext/string/inquiry.rb
index 1dcd949536..a796d5fb4f 100644
--- a/activesupport/lib/active_support/core_ext/string/inquiry.rb
+++ b/activesupport/lib/active_support/core_ext/string/inquiry.rb
@@ -1,4 +1,6 @@
-require 'active_support/string_inquirer'
+# frozen_string_literal: true
+
+require "active_support/string_inquirer"
 
 class String
   # Wraps the current string in the <tt>ActiveSupport::StringInquirer</tt> class,
diff --git a/activesupport/lib/active_support/core_ext/string/multibyte.rb b/activesupport/lib/active_support/core_ext/string/multibyte.rb
index cc6f2158e7..07c0d16398 100644
--- a/activesupport/lib/active_support/core_ext/string/multibyte.rb
+++ b/activesupport/lib/active_support/core_ext/string/multibyte.rb
@@ -1,4 +1,6 @@
-require 'active_support/multibyte'
+# frozen_string_literal: true
+
+require "active_support/multibyte"
 
 class String
   # == Multibyte proxy
@@ -14,6 +16,8 @@ class String
   #   >> "lj".mb_chars.upcase.to_s
   #   => "LJ"
   #
+  # NOTE: An above example is useful for pre Ruby 2.4. Ruby 2.4 supports Unicode case mappings.
+  #
   # == Method chaining
   #
   # All the methods on the Chars proxy which normally return a string will return a Chars object. This allows
diff --git a/activesupport/lib/active_support/core_ext/string/output_safety.rb b/activesupport/lib/active_support/core_ext/string/output_safety.rb
index 005ad93b08..f3bdc2977e 100644
--- a/activesupport/lib/active_support/core_ext/string/output_safety.rb
+++ b/activesupport/lib/active_support/core_ext/string/output_safety.rb
@@ -1,32 +1,32 @@
-require 'erb'
-require 'active_support/core_ext/kernel/singleton_class'
+# frozen_string_literal: true
+
+require "erb"
+require "active_support/core_ext/kernel/singleton_class"
+require "active_support/core_ext/module/redefine_method"
+require "active_support/multibyte/unicode"
 
 class ERB
   module Util
-    HTML_ESCAPE = { '&' => '&amp;',  '>' => '&gt;',   '<' => '&lt;', '"' => '&quot;', "'" => '&#39;' }
-    JSON_ESCAPE = { '&' => '\u0026', '>' => '\u003e', '<' => '\u003c', "\u2028" => '\u2028', "\u2029" => '\u2029' }
+    HTML_ESCAPE = { "&" => "&amp;",  ">" => "&gt;",   "<" => "&lt;", '"' => "&quot;", "'" => "&#39;" }
+    JSON_ESCAPE = { "&" => '\u0026', ">" => '\u003e', "<" => '\u003c', "\u2028" => '\u2028', "\u2029" => '\u2029' }
     HTML_ESCAPE_ONCE_REGEXP = /["><']|&(?!([a-zA-Z]+|(#\d+)|(#[xX][\dA-Fa-f]+));)/
     JSON_ESCAPE_REGEXP = /[\u2028\u2029&><]/u
 
     # A utility method for escaping HTML tag characters.
     # This method is also aliased as <tt>h</tt>.
     #
-    # In your ERB templates, use this method to escape any unsafe content. For example:
-    #   <%= h @person.name %>
-    #
     #   puts html_escape('is a > 0 & a < 10?')
     #   # => is a &gt; 0 &amp; a &lt; 10?
     def html_escape(s)
       unwrapped_html_escape(s).html_safe
     end
 
-    # Aliasing twice issues a warning "discarding old...". Remove first to avoid it.
-    remove_method(:h)
+    silence_redefinition_of_method :h
     alias h html_escape
 
     module_function :h
 
-    singleton_class.send(:remove_method, :html_escape)
+    singleton_class.silence_redefinition_of_method :html_escape
     module_function :html_escape
 
     # HTML escapes strings but doesn't wrap them with an ActiveSupport::SafeBuffer.
@@ -144,25 +144,23 @@ module ActiveSupport #:nodoc:
     # Raised when <tt>ActiveSupport::SafeBuffer#safe_concat</tt> is called on unsafe buffers.
     class SafeConcatError < StandardError
       def initialize
-        super 'Could not concatenate to the buffer because it is not html safe.'
+        super "Could not concatenate to the buffer because it is not html safe."
       end
     end
 
     def [](*args)
       if args.size < 2
         super
-      else
-        if html_safe?
-          new_safe_buffer = super
-
-          if new_safe_buffer
-            new_safe_buffer.instance_variable_set :@html_safe, true
-          end
+      elsif html_safe?
+        new_safe_buffer = super
 
-          new_safe_buffer
-        else
-          to_str[*args]
+        if new_safe_buffer
+          new_safe_buffer.instance_variable_set :@html_safe, true
         end
+
+        new_safe_buffer
+      else
+        to_str[*args]
       end
     end
 
@@ -171,7 +169,7 @@ module ActiveSupport #:nodoc:
       original_concat(value)
     end
 
-    def initialize(str = '')
+    def initialize(str = "")
       @html_safe = true
       super
     end
@@ -201,7 +199,7 @@ module ActiveSupport #:nodoc:
     def %(args)
       case args
       when Hash
-        escaped_args = Hash[args.map { |k,arg| [k, html_escape_interpolated_argument(arg)] }]
+        escaped_args = Hash[args.map { |k, arg| [k, html_escape_interpolated_argument(arg)] }]
       else
         escaped_args = Array(args).map { |arg| html_escape_interpolated_argument(arg) }
       end
@@ -242,9 +240,9 @@ module ActiveSupport #:nodoc:
 
     private
 
-    def html_escape_interpolated_argument(arg)
-      (!html_safe? || arg.html_safe?) ? arg : CGI.escapeHTML(arg.to_s)
-    end
+      def html_escape_interpolated_argument(arg)
+        (!html_safe? || arg.html_safe?) ? arg : CGI.escapeHTML(arg.to_s)
+      end
   end
 end
 
@@ -252,7 +250,7 @@ class String
   # Marks a string as trusted safe. It will be inserted into HTML with no
   # additional escaping performed. It is your responsibility to ensure that the
   # string contains no malicious content. This method is equivalent to the
-  # `raw` helper in views. It is recommended that you use `sanitize` instead of
+  # +raw+ helper in views. It is recommended that you use +sanitize+ instead of
   # this method. It should never be called on user input.
   def html_safe
     ActiveSupport::SafeBuffer.new(self)
diff --git a/activesupport/lib/active_support/core_ext/string/starts_ends_with.rb b/activesupport/lib/active_support/core_ext/string/starts_ends_with.rb
index 641acf62d0..919eb7a573 100644
--- a/activesupport/lib/active_support/core_ext/string/starts_ends_with.rb
+++ b/activesupport/lib/active_support/core_ext/string/starts_ends_with.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class String
   alias_method :starts_with?, :start_with?
   alias_method :ends_with?, :end_with?
diff --git a/activesupport/lib/active_support/core_ext/string/strip.rb b/activesupport/lib/active_support/core_ext/string/strip.rb
index 55b9b87352..cc26274e4a 100644
--- a/activesupport/lib/active_support/core_ext/string/strip.rb
+++ b/activesupport/lib/active_support/core_ext/string/strip.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class String
   # Strips indentation in heredocs.
   #
@@ -18,6 +20,6 @@ class String
   # Technically, it looks for the least indented non-empty line
   # in the whole string, and removes that amount of leading whitespace.
   def strip_heredoc
-    gsub(/^#{scan(/^[ \t]*(?=\S)/).min}/, ''.freeze)
+    gsub(/^#{scan(/^[ \t]*(?=\S)/).min}/, "".freeze)
   end
 end
diff --git a/activesupport/lib/active_support/core_ext/string/zones.rb b/activesupport/lib/active_support/core_ext/string/zones.rb
index 510c884c18..55dc231464 100644
--- a/activesupport/lib/active_support/core_ext/string/zones.rb
+++ b/activesupport/lib/active_support/core_ext/string/zones.rb
@@ -1,5 +1,7 @@
-require 'active_support/core_ext/string/conversions'
-require 'active_support/core_ext/time/zones'
+# frozen_string_literal: true
+
+require "active_support/core_ext/string/conversions"
+require "active_support/core_ext/time/zones"
 
 class String
   # Converts String to a TimeWithZone in the current zone if Time.zone or Time.zone_default
diff --git a/activesupport/lib/active_support/core_ext/struct.rb b/activesupport/lib/active_support/core_ext/struct.rb
deleted file mode 100644
index 1fde3db070..0000000000
--- a/activesupport/lib/active_support/core_ext/struct.rb
+++ /dev/null
@@ -1,3 +0,0 @@
-require 'active_support/deprecation'
-
-ActiveSupport::Deprecation.warn("This file is deprecated and will be removed in Rails 5.1 with no replacement.")
diff --git a/activesupport/lib/active_support/core_ext/time.rb b/activesupport/lib/active_support/core_ext/time.rb
index 0bce632222..c809def05f 100644
--- a/activesupport/lib/active_support/core_ext/time.rb
+++ b/activesupport/lib/active_support/core_ext/time.rb
@@ -1,5 +1,7 @@
-require 'active_support/core_ext/time/acts_like'
-require 'active_support/core_ext/time/calculations'
-require 'active_support/core_ext/time/compatibility'
-require 'active_support/core_ext/time/conversions'
-require 'active_support/core_ext/time/zones'
+# frozen_string_literal: true
+
+require "active_support/core_ext/time/acts_like"
+require "active_support/core_ext/time/calculations"
+require "active_support/core_ext/time/compatibility"
+require "active_support/core_ext/time/conversions"
+require "active_support/core_ext/time/zones"
diff --git a/activesupport/lib/active_support/core_ext/time/acts_like.rb b/activesupport/lib/active_support/core_ext/time/acts_like.rb
index 3f853b7893..8572b49639 100644
--- a/activesupport/lib/active_support/core_ext/time/acts_like.rb
+++ b/activesupport/lib/active_support/core_ext/time/acts_like.rb
@@ -1,4 +1,6 @@
-require 'active_support/core_ext/object/acts_like'
+# frozen_string_literal: true
+
+require "active_support/core_ext/object/acts_like"
 
 class Time
   # Duck-types as a Time-like class. See Object#acts_like?.
diff --git a/activesupport/lib/active_support/core_ext/time/calculations.rb b/activesupport/lib/active_support/core_ext/time/calculations.rb
index e81b48ab26..120768dec5 100644
--- a/activesupport/lib/active_support/core_ext/time/calculations.rb
+++ b/activesupport/lib/active_support/core_ext/time/calculations.rb
@@ -1,9 +1,11 @@
-require 'active_support/duration'
-require 'active_support/core_ext/time/conversions'
-require 'active_support/time_with_zone'
-require 'active_support/core_ext/time/zones'
-require 'active_support/core_ext/date_and_time/calculations'
-require 'active_support/core_ext/date/calculations'
+# frozen_string_literal: true
+
+require "active_support/duration"
+require "active_support/core_ext/time/conversions"
+require "active_support/time_with_zone"
+require "active_support/core_ext/time/zones"
+require "active_support/core_ext/date_and_time/calculations"
+require "active_support/core_ext/date/calculations"
 
 class Time
   include DateAndTime::Calculations
@@ -53,6 +55,29 @@ class Time
     end
     alias_method :at_without_coercion, :at
     alias_method :at, :at_with_coercion
+
+    # Creates a +Time+ instance from an RFC 3339 string.
+    #
+    #   Time.rfc3339('1999-12-31T14:00:00-10:00') # => 2000-01-01 00:00:00 -1000
+    #
+    # If the time or offset components are missing then an +ArgumentError+ will be raised.
+    #
+    #   Time.rfc3339('1999-12-31') # => ArgumentError: invalid date
+    def rfc3339(str)
+      parts = Date._rfc3339(str)
+
+      raise ArgumentError, "invalid date" if parts.empty?
+
+      Time.new(
+        parts.fetch(:year),
+        parts.fetch(:mon),
+        parts.fetch(:mday),
+        parts.fetch(:hour),
+        parts.fetch(:min),
+        parts.fetch(:sec) + parts.fetch(:sec_fraction, 0),
+        parts.fetch(:offset)
+      )
+    end
   end
 
   # Returns the number of seconds since 00:00:00.
@@ -61,7 +86,7 @@ class Time
   #   Time.new(2012, 8, 29, 12, 34, 56).seconds_since_midnight # => 45296.0
   #   Time.new(2012, 8, 29, 23, 59, 59).seconds_since_midnight # => 86399.0
   def seconds_since_midnight
-    to_i - change(:hour => 0).to_i + (usec / 1.0e+6)
+    to_i - change(hour: 0).to_i + (usec / 1.0e+6)
   end
 
   # Returns the number of seconds until 23:59:59.
@@ -84,36 +109,42 @@ class Time
   # to the +options+ parameter. The time options (<tt>:hour</tt>, <tt>:min</tt>,
   # <tt>:sec</tt>, <tt>:usec</tt>, <tt>:nsec</tt>) reset cascadingly, so if only
   # the hour is passed, then minute, sec, usec and nsec is set to 0. If the hour
-  # and minute is passed, then sec, usec and nsec is set to 0. The +options+
-  # parameter takes a hash with any of these keys: <tt>:year</tt>, <tt>:month</tt>,
-  # <tt>:day</tt>, <tt>:hour</tt>, <tt>:min</tt>, <tt>:sec</tt>, <tt>:usec</tt>
-  # <tt>:nsec</tt>. Pass either <tt>:usec</tt> or <tt>:nsec</tt>, not both.
+  # and minute is passed, then sec, usec and nsec is set to 0. The +options+ parameter
+  # takes a hash with any of these keys: <tt>:year</tt>, <tt>:month</tt>, <tt>:day</tt>,
+  # <tt>:hour</tt>, <tt>:min</tt>, <tt>:sec</tt>, <tt>:usec</tt>, <tt>:nsec</tt>,
+  # <tt>:offset</tt>. Pass either <tt>:usec</tt> or <tt>:nsec</tt>, not both.
   #
   #   Time.new(2012, 8, 29, 22, 35, 0).change(day: 1)              # => Time.new(2012, 8, 1, 22, 35, 0)
   #   Time.new(2012, 8, 29, 22, 35, 0).change(year: 1981, day: 1)  # => Time.new(1981, 8, 1, 22, 35, 0)
   #   Time.new(2012, 8, 29, 22, 35, 0).change(year: 1981, hour: 0) # => Time.new(1981, 8, 29, 0, 0, 0)
   def change(options)
-    new_year  = options.fetch(:year, year)
-    new_month = options.fetch(:month, month)
-    new_day   = options.fetch(:day, day)
-    new_hour  = options.fetch(:hour, hour)
-    new_min   = options.fetch(:min, options[:hour] ? 0 : min)
-    new_sec   = options.fetch(:sec, (options[:hour] || options[:min]) ? 0 : sec)
+    new_year   = options.fetch(:year, year)
+    new_month  = options.fetch(:month, month)
+    new_day    = options.fetch(:day, day)
+    new_hour   = options.fetch(:hour, hour)
+    new_min    = options.fetch(:min, options[:hour] ? 0 : min)
+    new_sec    = options.fetch(:sec, (options[:hour] || options[:min]) ? 0 : sec)
+    new_offset = options.fetch(:offset, nil)
 
     if new_nsec = options[:nsec]
       raise ArgumentError, "Can't change both :nsec and :usec at the same time: #{options.inspect}" if options[:usec]
       new_usec = Rational(new_nsec, 1000)
     else
-      new_usec  = options.fetch(:usec, (options[:hour] || options[:min] || options[:sec]) ? 0 : Rational(nsec, 1000))
+      new_usec = options.fetch(:usec, (options[:hour] || options[:min] || options[:sec]) ? 0 : Rational(nsec, 1000))
     end
 
-    if utc?
-      ::Time.utc(new_year, new_month, new_day, new_hour, new_min, new_sec, new_usec)
+    raise ArgumentError, "argument out of range" if new_usec >= 1000000
+
+    new_sec += Rational(new_usec, 1000000)
+
+    if new_offset
+      ::Time.new(new_year, new_month, new_day, new_hour, new_min, new_sec, new_offset)
+    elsif utc?
+      ::Time.utc(new_year, new_month, new_day, new_hour, new_min, new_sec)
     elsif zone
-      ::Time.local(new_year, new_month, new_day, new_hour, new_min, new_sec, new_usec)
+      ::Time.local(new_year, new_month, new_day, new_hour, new_min, new_sec)
     else
-      raise ArgumentError, 'argument out of range' if new_usec >= 1000000
-      ::Time.new(new_year, new_month, new_day, new_hour, new_min, new_sec + (new_usec.to_r / 1000000), utc_offset)
+      ::Time.new(new_year, new_month, new_day, new_hour, new_min, new_sec, utc_offset)
     end
   end
 
@@ -141,7 +172,7 @@ class Time
 
     d = to_date.advance(options)
     d = d.gregorian if d.julian?
-    time_advanced_by_date = change(:year => d.year, :month => d.month, :day => d.day)
+    time_advanced_by_date = change(year: d.year, month: d.month, day: d.day)
     seconds_to_advance = \
       options.fetch(:seconds, 0) +
       options.fetch(:minutes, 0) * 60 +
@@ -169,7 +200,7 @@ class Time
 
   # Returns a new Time representing the start of the day (0:00)
   def beginning_of_day
-    change(:hour => 0)
+    change(hour: 0)
   end
   alias :midnight :beginning_of_day
   alias :at_midnight :beginning_of_day
@@ -177,7 +208,7 @@ class Time
 
   # Returns a new Time representing the middle of the day (12:00)
   def middle_of_day
-    change(:hour => 12)
+    change(hour: 12)
   end
   alias :midday :middle_of_day
   alias :noon :middle_of_day
@@ -188,41 +219,41 @@ class Time
   # Returns a new Time representing the end of the day, 23:59:59.999999
   def end_of_day
     change(
-      :hour => 23,
-      :min => 59,
-      :sec => 59,
-      :usec => Rational(999999999, 1000)
+      hour: 23,
+      min: 59,
+      sec: 59,
+      usec: Rational(999999999, 1000)
     )
   end
   alias :at_end_of_day :end_of_day
 
   # Returns a new Time representing the start of the hour (x:00)
   def beginning_of_hour
-    change(:min => 0)
+    change(min: 0)
   end
   alias :at_beginning_of_hour :beginning_of_hour
 
   # Returns a new Time representing the end of the hour, x:59:59.999999
   def end_of_hour
     change(
-      :min => 59,
-      :sec => 59,
-      :usec => Rational(999999999, 1000)
+      min: 59,
+      sec: 59,
+      usec: Rational(999999999, 1000)
     )
   end
   alias :at_end_of_hour :end_of_hour
 
   # Returns a new Time representing the start of the minute (x:xx:00)
   def beginning_of_minute
-    change(:sec => 0)
+    change(sec: 0)
   end
   alias :at_beginning_of_minute :beginning_of_minute
 
   # Returns a new Time representing the end of the minute, x:xx:59.999999
   def end_of_minute
     change(
-      :sec => 59,
-      :usec => Rational(999999999, 1000)
+      sec: 59,
+      usec: Rational(999999999, 1000)
     )
   end
   alias :at_end_of_minute :end_of_minute
@@ -281,5 +312,4 @@ class Time
   end
   alias_method :eql_without_coercion, :eql?
   alias_method :eql?, :eql_with_coercion
-
 end
diff --git a/activesupport/lib/active_support/core_ext/time/compatibility.rb b/activesupport/lib/active_support/core_ext/time/compatibility.rb
index 945319461b..495e4f307b 100644
--- a/activesupport/lib/active_support/core_ext/time/compatibility.rb
+++ b/activesupport/lib/active_support/core_ext/time/compatibility.rb
@@ -1,5 +1,16 @@
-require 'active_support/core_ext/date_and_time/compatibility'
+# frozen_string_literal: true
+
+require "active_support/core_ext/date_and_time/compatibility"
+require "active_support/core_ext/module/redefine_method"
 
 class Time
-  prepend DateAndTime::Compatibility
+  include DateAndTime::Compatibility
+
+  silence_redefinition_of_method :to_time
+
+  # Either return +self+ or the time in the local system timezone depending
+  # on the setting of +ActiveSupport.to_time_preserves_timezone+.
+  def to_time
+    preserve_timezone ? self : getlocal
+  end
 end
diff --git a/activesupport/lib/active_support/core_ext/time/conversions.rb b/activesupport/lib/active_support/core_ext/time/conversions.rb
index 536c4bf525..345cb2832c 100644
--- a/activesupport/lib/active_support/core_ext/time/conversions.rb
+++ b/activesupport/lib/active_support/core_ext/time/conversions.rb
@@ -1,24 +1,26 @@
-require 'active_support/inflector/methods'
-require 'active_support/values/time_zone'
+# frozen_string_literal: true
+
+require "active_support/inflector/methods"
+require "active_support/values/time_zone"
 
 class Time
   DATE_FORMATS = {
-    :db           => '%Y-%m-%d %H:%M:%S',
-    :number       => '%Y%m%d%H%M%S',
-    :nsec         => '%Y%m%d%H%M%S%9N',
-    :usec         => '%Y%m%d%H%M%S%6N',
-    :time         => '%H:%M',
-    :short        => '%d %b %H:%M',
-    :long         => '%B %d, %Y %H:%M',
-    :long_ordinal => lambda { |time|
+    db: "%Y-%m-%d %H:%M:%S",
+    number: "%Y%m%d%H%M%S",
+    nsec: "%Y%m%d%H%M%S%9N",
+    usec: "%Y%m%d%H%M%S%6N",
+    time: "%H:%M",
+    short: "%d %b %H:%M",
+    long: "%B %d, %Y %H:%M",
+    long_ordinal: lambda { |time|
       day_format = ActiveSupport::Inflector.ordinalize(time.day)
       time.strftime("%B #{day_format}, %Y %H:%M")
     },
-    :rfc822       => lambda { |time|
+    rfc822: lambda { |time|
       offset_format = time.formatted_offset(false)
       time.strftime("%a, %d %b %Y %H:%M:%S #{offset_format}")
     },
-    :iso8601      => lambda { |time| time.iso8601 }
+    iso8601: lambda { |time| time.iso8601 }
   }
 
   # Converts to a formatted string. See DATE_FORMATS for built-in formats.
@@ -64,4 +66,7 @@ class Time
   def formatted_offset(colon = true, alternate_utc_string = nil)
     utc? && alternate_utc_string || ActiveSupport::TimeZone.seconds_to_utc_offset(utc_offset, colon)
   end
+
+  # Aliased to +xmlschema+ for compatibility with +DateTime+
+  alias_method :rfc3339, :xmlschema
 end
diff --git a/activesupport/lib/active_support/core_ext/time/marshal.rb b/activesupport/lib/active_support/core_ext/time/marshal.rb
deleted file mode 100644
index 467bad1726..0000000000
--- a/activesupport/lib/active_support/core_ext/time/marshal.rb
+++ /dev/null
@@ -1,3 +0,0 @@
-require 'active_support/deprecation'
-
-ActiveSupport::Deprecation.warn("This is deprecated and will be removed in Rails 5.1 with no replacement.")
diff --git a/activesupport/lib/active_support/core_ext/time/zones.rb b/activesupport/lib/active_support/core_ext/time/zones.rb
index 7a60f94996..a5588fd488 100644
--- a/activesupport/lib/active_support/core_ext/time/zones.rb
+++ b/activesupport/lib/active_support/core_ext/time/zones.rb
@@ -1,6 +1,8 @@
-require 'active_support/time_with_zone'
-require 'active_support/core_ext/time/acts_like'
-require 'active_support/core_ext/date_and_time/zones'
+# frozen_string_literal: true
+
+require "active_support/time_with_zone"
+require "active_support/core_ext/time/acts_like"
+require "active_support/core_ext/date_and_time/zones"
 
 class Time
   include DateAndTime::Zones
@@ -53,10 +55,10 @@ class Time
     #     end
     #   end
     #
-    #  NOTE: This won't affect any <tt>ActiveSupport::TimeWithZone</tt>
-    #  objects that have already been created, e.g. any model timestamp
-    #  attributes that have been read before the block will remain in
-    #  the application's default timezone.
+    # NOTE: This won't affect any <tt>ActiveSupport::TimeWithZone</tt>
+    # objects that have already been created, e.g. any model timestamp
+    # attributes that have been read before the block will remain in
+    # the application's default timezone.
     def use_zone(time_zone)
       new_zone = find_zone!(time_zone)
       begin
diff --git a/activesupport/lib/active_support/core_ext/uri.rb b/activesupport/lib/active_support/core_ext/uri.rb
index c6c183edd9..c93c0b5c2d 100644
--- a/activesupport/lib/active_support/core_ext/uri.rb
+++ b/activesupport/lib/active_support/core_ext/uri.rb
@@ -1,16 +1,19 @@
-require 'uri'
+# frozen_string_literal: true
+
+require "uri"
 str = "\xE6\x97\xA5\xE6\x9C\xAC\xE8\xAA\x9E" # Ni-ho-nn-go in UTF-8, means Japanese.
 parser = URI::Parser.new
 
 unless str == parser.unescape(parser.escape(str))
+  require "active_support/core_ext/module/redefine_method"
   URI::Parser.class_eval do
-    remove_method :unescape
+    silence_redefinition_of_method :unescape
     def unescape(str, escaped = /%[a-fA-F\d]{2}/)
       # TODO: Are we actually sure that ASCII == UTF-8?
       # YK: My initial experiments say yes, but let's be sure please
       enc = str.encoding
       enc = Encoding::UTF_8 if enc == Encoding::US_ASCII
-      str.gsub(escaped) { |match| [match[1, 2].hex].pack('C') }.force_encoding(enc)
+      str.gsub(escaped) { |match| [match[1, 2].hex].pack("C") }.force_encoding(enc)
     end
   end
 end
diff --git a/activesupport/lib/active_support/current_attributes.rb b/activesupport/lib/active_support/current_attributes.rb
new file mode 100644
index 0000000000..4e6d8e4585
--- /dev/null
+++ b/activesupport/lib/active_support/current_attributes.rb
@@ -0,0 +1,195 @@
+# frozen_string_literal: true
+
+module ActiveSupport
+  # Abstract super class that provides a thread-isolated attributes singleton, which resets automatically
+  # before and after each request. This allows you to keep all the per-request attributes easily
+  # available to the whole system.
+  #
+  # The following full app-like example demonstrates how to use a Current class to
+  # facilitate easy access to the global, per-request attributes without passing them deeply
+  # around everywhere:
+  #
+  #   # app/models/current.rb
+  #   class Current < ActiveSupport::CurrentAttributes
+  #     attribute :account, :user
+  #     attribute :request_id, :user_agent, :ip_address
+  #
+  #     resets { Time.zone = nil }
+  #
+  #     def user=(user)
+  #       super
+  #       self.account = user.account
+  #       Time.zone    = user.time_zone
+  #     end
+  #   end
+  #
+  #   # app/controllers/concerns/authentication.rb
+  #   module Authentication
+  #     extend ActiveSupport::Concern
+  #
+  #     included do
+  #       before_action :authenticate
+  #     end
+  #
+  #     private
+  #       def authenticate
+  #         if authenticated_user = User.find_by(id: cookies.encrypted[:user_id])
+  #           Current.user = authenticated_user
+  #         else
+  #           redirect_to new_session_url
+  #         end
+  #       end
+  #   end
+  #
+  #   # app/controllers/concerns/set_current_request_details.rb
+  #   module SetCurrentRequestDetails
+  #     extend ActiveSupport::Concern
+  #
+  #     included do
+  #       before_action do
+  #         Current.request_id = request.uuid
+  #         Current.user_agent = request.user_agent
+  #         Current.ip_address = request.ip
+  #       end
+  #     end
+  #   end
+  #
+  #   class ApplicationController < ActionController::Base
+  #     include Authentication
+  #     include SetCurrentRequestDetails
+  #   end
+  #
+  #   class MessagesController < ApplicationController
+  #     def create
+  #       Current.account.messages.create(message_params)
+  #     end
+  #   end
+  #
+  #   class Message < ApplicationRecord
+  #     belongs_to :creator, default: -> { Current.user }
+  #     after_create { |message| Event.create(record: message) }
+  #   end
+  #
+  #   class Event < ApplicationRecord
+  #     before_create do
+  #       self.request_id = Current.request_id
+  #       self.user_agent = Current.user_agent
+  #       self.ip_address = Current.ip_address
+  #     end
+  #   end
+  #
+  # A word of caution: It's easy to overdo a global singleton like Current and tangle your model as a result.
+  # Current should only be used for a few, top-level globals, like account, user, and request details.
+  # The attributes stuck in Current should be used by more or less all actions on all requests. If you start
+  # sticking controller-specific attributes in there, you're going to create a mess.
+  class CurrentAttributes
+    include ActiveSupport::Callbacks
+    define_callbacks :reset
+
+    class << self
+      # Returns singleton instance for this class in this thread. If none exists, one is created.
+      def instance
+        current_instances[name] ||= new
+      end
+
+      # Declares one or more attributes that will be given both class and instance accessor methods.
+      def attribute(*names)
+        generated_attribute_methods.module_eval do
+          names.each do |name|
+            define_method(name) do
+              attributes[name.to_sym]
+            end
+
+            define_method("#{name}=") do |attribute|
+              attributes[name.to_sym] = attribute
+            end
+          end
+        end
+
+        names.each do |name|
+          define_singleton_method(name) do
+            instance.public_send(name)
+          end
+
+          define_singleton_method("#{name}=") do |attribute|
+            instance.public_send("#{name}=", attribute)
+          end
+        end
+      end
+
+      # Calls this block after #reset is called on the instance. Used for resetting external collaborators, like Time.zone.
+      def resets(&block)
+        set_callback :reset, :after, &block
+      end
+
+      delegate :set, :reset, to: :instance
+
+      def reset_all # :nodoc:
+        current_instances.each_value(&:reset)
+      end
+
+      def clear_all # :nodoc:
+        reset_all
+        current_instances.clear
+      end
+
+      private
+        def generated_attribute_methods
+          @generated_attribute_methods ||= Module.new.tap { |mod| include mod }
+        end
+
+        def current_instances
+          Thread.current[:current_attributes_instances] ||= {}
+        end
+
+        def method_missing(name, *args, &block)
+          # Caches the method definition as a singleton method of the receiver.
+          #
+          # By letting #delegate handle it, we avoid an enclosure that'll capture args.
+          singleton_class.delegate name, to: :instance
+
+          send(name, *args, &block)
+        end
+    end
+
+    attr_accessor :attributes
+
+    def initialize
+      @attributes = {}
+    end
+
+    # Expose one or more attributes within a block. Old values are returned after the block concludes.
+    # Example demonstrating the common use of needing to set Current attributes outside the request-cycle:
+    #
+    #   class Chat::PublicationJob < ApplicationJob
+    #     def perform(attributes, room_number, creator)
+    #       Current.set(person: creator) do
+    #         Chat::Publisher.publish(attributes: attributes, room_number: room_number)
+    #       end
+    #     end
+    #   end
+    def set(set_attributes)
+      old_attributes = compute_attributes(set_attributes.keys)
+      assign_attributes(set_attributes)
+      yield
+    ensure
+      assign_attributes(old_attributes)
+    end
+
+    # Reset all attributes. Should be called before and after actions, when used as a per-request singleton.
+    def reset
+      run_callbacks :reset do
+        self.attributes = {}
+      end
+    end
+
+    private
+      def assign_attributes(new_attributes)
+        new_attributes.each { |key, value| public_send("#{key}=", value) }
+      end
+
+      def compute_attributes(keys)
+        keys.collect { |key| [ key, public_send(key) ] }.to_h
+      end
+  end
+end
diff --git a/activesupport/lib/active_support/dependencies.rb b/activesupport/lib/active_support/dependencies.rb
index 57f6286de3..82c10b3079 100644
--- a/activesupport/lib/active_support/dependencies.rb
+++ b/activesupport/lib/active_support/dependencies.rb
@@ -1,26 +1,26 @@
-require 'set'
-require 'thread'
-require 'concurrent/map'
-require 'pathname'
-require 'active_support/core_ext/module/aliasing'
-require 'active_support/core_ext/module/attribute_accessors'
-require 'active_support/core_ext/module/introspection'
-require 'active_support/core_ext/module/anonymous'
-require 'active_support/core_ext/module/qualified_const'
-require 'active_support/core_ext/object/blank'
-require 'active_support/core_ext/kernel/reporting'
-require 'active_support/core_ext/load_error'
-require 'active_support/core_ext/name_error'
-require 'active_support/core_ext/string/starts_ends_with'
+# frozen_string_literal: true
+
+require "set"
+require "thread"
+require "concurrent/map"
+require "pathname"
+require "active_support/core_ext/module/aliasing"
+require "active_support/core_ext/module/attribute_accessors"
+require "active_support/core_ext/module/introspection"
+require "active_support/core_ext/module/anonymous"
+require "active_support/core_ext/object/blank"
+require "active_support/core_ext/kernel/reporting"
+require "active_support/core_ext/load_error"
+require "active_support/core_ext/name_error"
+require "active_support/core_ext/string/starts_ends_with"
 require "active_support/dependencies/interlock"
-require 'active_support/inflector'
+require "active_support/inflector"
 
 module ActiveSupport #:nodoc:
   module Dependencies #:nodoc:
     extend self
 
-    mattr_accessor :interlock
-    self.interlock = Interlock.new
+    mattr_accessor :interlock, default: Interlock.new
 
     # :doc:
 
@@ -47,46 +47,37 @@ module ActiveSupport #:nodoc:
     # :nodoc:
 
     # Should we turn on Ruby warnings on the first load of dependent files?
-    mattr_accessor :warnings_on_first_load
-    self.warnings_on_first_load = false
+    mattr_accessor :warnings_on_first_load, default: false
 
     # All files ever loaded.
-    mattr_accessor :history
-    self.history = Set.new
+    mattr_accessor :history, default: Set.new
 
     # All files currently loaded.
-    mattr_accessor :loaded
-    self.loaded = Set.new
+    mattr_accessor :loaded, default: Set.new
 
     # Stack of files being loaded.
-    mattr_accessor :loading
-    self.loading = []
+    mattr_accessor :loading, default: []
 
     # Should we load files or require them?
-    mattr_accessor :mechanism
-    self.mechanism = ENV['NO_RELOAD'] ? :require : :load
+    mattr_accessor :mechanism, default: ENV["NO_RELOAD"] ? :require : :load
 
     # The set of directories from which we may automatically load files. Files
     # under these directories will be reloaded on each request in development mode,
     # unless the directory also appears in autoload_once_paths.
-    mattr_accessor :autoload_paths
-    self.autoload_paths = []
+    mattr_accessor :autoload_paths, default: []
 
     # The set of directories from which automatically loaded constants are loaded
     # only once. All directories in this set must also be present in +autoload_paths+.
-    mattr_accessor :autoload_once_paths
-    self.autoload_once_paths = []
+    mattr_accessor :autoload_once_paths, default: []
 
     # An array of qualified constant names that have been loaded. Adding a name
     # to this array will cause it to be unloaded the next time Dependencies are
     # cleared.
-    mattr_accessor :autoloaded_constants
-    self.autoloaded_constants = []
+    mattr_accessor :autoloaded_constants, default: []
 
     # An array of constant names that need to be unloaded on every request. Used
     # to allow arbitrary constants to be marked for unloading.
-    mattr_accessor :explicitly_unloadable_constants
-    self.explicitly_unloadable_constants = []
+    mattr_accessor :explicitly_unloadable_constants, default: []
 
     # The WatchStack keeps a stack of the modules being watched as files are
     # loaded. If a file in the process of being loaded (parent.rb) triggers the
@@ -94,7 +85,7 @@ module ActiveSupport #:nodoc:
     # handles the new constants.
     #
     # If child.rb is being autoloaded, its constants will be added to
-    # autoloaded_constants. If it was being `require`d, they will be discarded.
+    # autoloaded_constants. If it was being required, they will be discarded.
     #
     # This is handled by walking back up the watch stack and adding the constants
     # found by child.rb to the list of original constants in parent.rb.
@@ -108,7 +99,7 @@ module ActiveSupport #:nodoc:
 
       def initialize
         @watching = []
-        @stack = Hash.new { |h,k| h[k] = [] }
+        @stack = Hash.new { |h, k| h[k] = [] }
       end
 
       def each(&block)
@@ -170,14 +161,13 @@ module ActiveSupport #:nodoc:
       end
 
       private
-      def pop_modules(modules)
-        modules.each { |mod| @stack[mod].pop }
-      end
+        def pop_modules(modules)
+          modules.each { |mod| @stack[mod].pop }
+        end
     end
 
     # An internal stack used to record which constants are loaded by any block.
-    mattr_accessor :constant_watch_stack
-    self.constant_watch_stack = WatchStack.new
+    mattr_accessor :constant_watch_stack, default: WatchStack.new
 
     # Module includes this module.
     module ModuleConstMissing #:nodoc:
@@ -243,7 +233,7 @@ module ActiveSupport #:nodoc:
       # resolution deterministic for constants with the same relative name in
       # different namespaces whose evaluation would depend on load order
       # otherwise.
-      def require_dependency(file_name, message = "No such file to load -- %s")
+      def require_dependency(file_name, message = "No such file to load -- %s.rb")
         file_name = file_name.to_path if file_name.respond_to?(:to_path)
         unless file_name.is_a?(String)
           raise ArgumentError, "the file name must either be a String or implement #to_path -- you passed #{file_name.inspect}"
@@ -282,17 +272,17 @@ module ActiveSupport #:nodoc:
 
       private
 
-      def load(file, wrap = false)
-        result = false
-        load_dependency(file) { result = super }
-        result
-      end
+        def load(file, wrap = false)
+          result = false
+          load_dependency(file) { result = super }
+          result
+        end
 
-      def require(file)
-        result = false
-        load_dependency(file) { result = super }
-        result
-      end
+        def require(file)
+          result = false
+          load_dependency(file) { result = super }
+          result
+        end
     end
 
     # Exception file-blaming.
@@ -371,7 +361,7 @@ module ActiveSupport #:nodoc:
             load_args = ["#{file_name}.rb"]
             load_args << const_path unless const_path.nil?
 
-            if !warnings_on_first_load or history.include?(expanded)
+            if !warnings_on_first_load || history.include?(expanded)
               result = load_file(*load_args)
             else
               enable_warnings { result = load_file(*load_args) }
@@ -503,7 +493,7 @@ module ActiveSupport #:nodoc:
 
       if file_path
         expanded = File.expand_path(file_path)
-        expanded.sub!(/\.rb\z/, ''.freeze)
+        expanded.sub!(/\.rb\z/, "".freeze)
 
         if loading.include?(expanded)
           raise "Circular dependency detected while autoloading constant #{qualified_name}"
@@ -547,7 +537,7 @@ module ActiveSupport #:nodoc:
       end
 
       name_error = NameError.new("uninitialized constant #{qualified_name}", const_name)
-      name_error.set_backtrace(caller.reject {|l| l.starts_with? __FILE__ })
+      name_error.set_backtrace(caller.reject { |l| l.starts_with? __FILE__ })
       raise name_error
     end
 
@@ -591,7 +581,7 @@ module ActiveSupport #:nodoc:
 
       def store(klass)
         return self unless klass.respond_to?(:name)
-        raise(ArgumentError, 'anonymous classes cannot be cached') if klass.name.empty?
+        raise(ArgumentError, "anonymous classes cannot be cached") if klass.name.empty?
         @store[klass.name] = klass
         self
       end
@@ -625,7 +615,7 @@ module ActiveSupport #:nodoc:
       return false if desc.is_a?(Module) && desc.anonymous?
       name = to_constant_name desc
       return false unless qualified_const_defined?(name)
-      return autoloaded_constants.include?(name)
+      autoloaded_constants.include?(name)
     end
 
     # Will the provided constant descriptor be unloaded?
@@ -675,29 +665,29 @@ module ActiveSupport #:nodoc:
     # A module, class, symbol, or string may be provided.
     def to_constant_name(desc) #:nodoc:
       case desc
-        when String then desc.sub(/^::/, '')
-        when Symbol then desc.to_s
-        when Module
-          desc.name ||
-            raise(ArgumentError, "Anonymous modules have no name to be referenced by")
+      when String then desc.sub(/^::/, "")
+      when Symbol then desc.to_s
+      when Module
+        desc.name ||
+          raise(ArgumentError, "Anonymous modules have no name to be referenced by")
         else raise TypeError, "Not a valid constant descriptor: #{desc.inspect}"
       end
     end
 
     def remove_constant(const) #:nodoc:
       # Normalize ::Foo, ::Object::Foo, Object::Foo, Object::Object::Foo, etc. as Foo.
-      normalized = const.to_s.sub(/\A::/, '')
-      normalized.sub!(/\A(Object::)+/, '')
+      normalized = const.to_s.sub(/\A::/, "")
+      normalized.sub!(/\A(Object::)+/, "")
 
-      constants = normalized.split('::')
+      constants = normalized.split("::")
       to_remove = constants.pop
 
       # Remove the file path from the loaded list.
       file_path = search_for_file(const.underscore)
       if file_path
         expanded = File.expand_path(file_path)
-        expanded.sub!(/\.rb\z/, '')
-        self.loaded.delete(expanded)
+        expanded.sub!(/\.rb\z/, "")
+        loaded.delete(expanded)
       end
 
       if constants.empty?
@@ -710,7 +700,7 @@ module ActiveSupport #:nodoc:
         # here than require the caller to be clever. We check the parent
         # rather than the very const argument because we do not want to
         # trigger Kernel#autoloads, see the comment below.
-        parent_name = constants.join('::')
+        parent_name = constants.join("::")
         return unless qualified_const_defined?(parent_name)
         parent = constantize(parent_name)
       end
diff --git a/activesupport/lib/active_support/dependencies/autoload.rb b/activesupport/lib/active_support/dependencies/autoload.rb
index 13036d521d..1cee85d98f 100644
--- a/activesupport/lib/active_support/dependencies/autoload.rb
+++ b/activesupport/lib/active_support/dependencies/autoload.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require "active_support/inflector/methods"
 
 module ActiveSupport
diff --git a/activesupport/lib/active_support/dependencies/interlock.rb b/activesupport/lib/active_support/dependencies/interlock.rb
index f1865ca2f8..948be75638 100644
--- a/activesupport/lib/active_support/dependencies/interlock.rb
+++ b/activesupport/lib/active_support/dependencies/interlock.rb
@@ -1,4 +1,6 @@
-require 'active_support/concurrency/share_lock'
+# frozen_string_literal: true
+
+require "active_support/concurrency/share_lock"
 
 module ActiveSupport #:nodoc:
   module Dependencies #:nodoc:
@@ -46,6 +48,10 @@ module ActiveSupport #:nodoc:
           yield
         end
       end
+
+      def raw_state(&block) # :nodoc:
+        @lock.raw_state(&block)
+      end
     end
   end
 end
diff --git a/activesupport/lib/active_support/deprecation.rb b/activesupport/lib/active_support/deprecation.rb
index b581710067..a1ad2ca465 100644
--- a/activesupport/lib/active_support/deprecation.rb
+++ b/activesupport/lib/active_support/deprecation.rb
@@ -1,4 +1,6 @@
-require 'singleton'
+# frozen_string_literal: true
+
+require "singleton"
 
 module ActiveSupport
   # \Deprecation specifies the API used by Rails to deprecate methods, instance
@@ -12,12 +14,13 @@ module ActiveSupport
     # a circular require warning for active_support/deprecation.rb.
     #
     # So, we define the constant first, and load dependencies later.
-    require 'active_support/deprecation/instance_delegator'
-    require 'active_support/deprecation/behaviors'
-    require 'active_support/deprecation/reporting'
-    require 'active_support/deprecation/method_wrappers'
-    require 'active_support/deprecation/proxy_wrappers'
-    require 'active_support/core_ext/module/deprecation'
+    require "active_support/deprecation/instance_delegator"
+    require "active_support/deprecation/behaviors"
+    require "active_support/deprecation/reporting"
+    require "active_support/deprecation/constant_accessor"
+    require "active_support/deprecation/method_wrappers"
+    require "active_support/deprecation/proxy_wrappers"
+    require "active_support/core_ext/module/deprecation"
 
     include Singleton
     include InstanceDelegator
@@ -29,10 +32,10 @@ module ActiveSupport
     attr_accessor :deprecation_horizon
 
     # It accepts two parameters on initialization. The first is a version of library
-    # and the second is a library name
+    # and the second is a library name.
     #
     #   ActiveSupport::Deprecation.new('2.0', 'MyLibrary')
-    def initialize(deprecation_horizon = '5.2', gem_name = 'Rails')
+    def initialize(deprecation_horizon = "6.0", gem_name = "Rails")
       self.gem_name = gem_name
       self.deprecation_horizon = deprecation_horizon
       # By default, warnings are not silenced and debugging is off.
diff --git a/activesupport/lib/active_support/deprecation/behaviors.rb b/activesupport/lib/active_support/deprecation/behaviors.rb
index 35a9e5f8b8..581db5f449 100644
--- a/activesupport/lib/active_support/deprecation/behaviors.rb
+++ b/activesupport/lib/active_support/deprecation/behaviors.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require "active_support/notifications"
 
 module ActiveSupport
@@ -9,35 +11,39 @@ module ActiveSupport
   class Deprecation
     # Default warning behaviors per Rails.env.
     DEFAULT_BEHAVIORS = {
-      raise: ->(message, callstack) {
+      raise: ->(message, callstack, deprecation_horizon, gem_name) {
         e = DeprecationException.new(message)
         e.set_backtrace(callstack.map(&:to_s))
         raise e
       },
 
-      stderr: ->(message, callstack) {
+      stderr: ->(message, callstack, deprecation_horizon, gem_name) {
         $stderr.puts(message)
         $stderr.puts callstack.join("\n  ") if debug
       },
 
-      log: ->(message, callstack) {
+      log: ->(message, callstack, deprecation_horizon, gem_name) {
         logger =
             if defined?(Rails.logger) && Rails.logger
               Rails.logger
             else
-              require 'active_support/logger'
+              require "active_support/logger"
               ActiveSupport::Logger.new($stderr)
             end
         logger.warn message
         logger.debug callstack.join("\n  ") if debug
       },
 
-      notify: ->(message, callstack) {
-        ActiveSupport::Notifications.instrument("deprecation.rails",
-                                                :message => message, :callstack => callstack)
+      notify: ->(message, callstack, deprecation_horizon, gem_name) {
+        notification_name = "deprecation.#{gem_name.underscore.tr('/', '_')}"
+        ActiveSupport::Notifications.instrument(notification_name,
+                                                message: message,
+                                                callstack: callstack,
+                                                gem_name: gem_name,
+                                                deprecation_horizon: deprecation_horizon)
       },
 
-      silence: ->(message, callstack) {},
+      silence: ->(message, callstack, deprecation_horizon, gem_name) {},
     }
 
     # Behavior module allows to determine how to display deprecation messages.
@@ -83,8 +89,17 @@ module ActiveSupport
       #     # custom stuff
       #   }
       def behavior=(behavior)
-        @behavior = Array(behavior).map { |b| DEFAULT_BEHAVIORS[b] || b }
+        @behavior = Array(behavior).map { |b| DEFAULT_BEHAVIORS[b] || arity_coerce(b) }
       end
+
+      private
+        def arity_coerce(behavior)
+          if behavior.arity == 4 || behavior.arity == -1
+            behavior
+          else
+            -> message, callstack, _, _ { behavior.call(message, callstack) }
+          end
+        end
     end
   end
 end
diff --git a/activesupport/lib/active_support/deprecation/constant_accessor.rb b/activesupport/lib/active_support/deprecation/constant_accessor.rb
new file mode 100644
index 0000000000..1ed0015812
--- /dev/null
+++ b/activesupport/lib/active_support/deprecation/constant_accessor.rb
@@ -0,0 +1,52 @@
+# frozen_string_literal: true
+
+module ActiveSupport
+  class Deprecation
+    # DeprecatedConstantAccessor transforms a constant into a deprecated one by
+    # hooking +const_missing+.
+    #
+    # It takes the names of an old (deprecated) constant and of a new constant
+    # (both in string form) and optionally a deprecator. The deprecator defaults
+    # to +ActiveSupport::Deprecator+ if none is specified.
+    #
+    # The deprecated constant now returns the same object as the new one rather
+    # than a proxy object, so it can be used transparently in +rescue+ blocks
+    # etc.
+    #
+    #   PLANETS = %w(mercury venus earth mars jupiter saturn uranus neptune pluto)
+    #
+    #   # (In a later update, the original implementation of `PLANETS` has been removed.)
+    #
+    #   PLANETS_POST_2006 = %w(mercury venus earth mars jupiter saturn uranus neptune)
+    #   include ActiveSupport::Deprecation::DeprecatedConstantAccessor
+    #   deprecate_constant 'PLANETS', 'PLANETS_POST_2006'
+    #
+    #   PLANETS.map { |planet| planet.capitalize }
+    #   # => DEPRECATION WARNING: PLANETS is deprecated! Use PLANETS_POST_2006 instead.
+    #        (Backtrace information…)
+    #        ["Mercury", "Venus", "Earth", "Mars", "Jupiter", "Saturn", "Uranus", "Neptune"]
+    module DeprecatedConstantAccessor
+      def self.included(base)
+        require "active_support/inflector/methods"
+
+        extension = Module.new do
+          def const_missing(missing_const_name)
+            if class_variable_defined?(:@@_deprecated_constants)
+              if (replacement = class_variable_get(:@@_deprecated_constants)[missing_const_name.to_s])
+                replacement[:deprecator].warn(replacement[:message] || "#{name}::#{missing_const_name} is deprecated! Use #{replacement[:new]} instead.", caller_locations)
+                return ActiveSupport::Inflector.constantize(replacement[:new].to_s)
+              end
+            end
+            super
+          end
+
+          def deprecate_constant(const_name, new_constant, message: nil, deprecator: ActiveSupport::Deprecation.instance)
+            class_variable_set(:@@_deprecated_constants, {}) unless class_variable_defined?(:@@_deprecated_constants)
+            class_variable_get(:@@_deprecated_constants)[const_name.to_s] = { new: new_constant, message: message, deprecator: deprecator }
+          end
+        end
+        base.singleton_class.prepend extension
+      end
+    end
+  end
+end
diff --git a/activesupport/lib/active_support/deprecation/instance_delegator.rb b/activesupport/lib/active_support/deprecation/instance_delegator.rb
index 8472a58add..8beda373a2 100644
--- a/activesupport/lib/active_support/deprecation/instance_delegator.rb
+++ b/activesupport/lib/active_support/deprecation/instance_delegator.rb
@@ -1,11 +1,14 @@
-require 'active_support/core_ext/kernel/singleton_class'
-require 'active_support/core_ext/module/delegation'
+# frozen_string_literal: true
+
+require "active_support/core_ext/kernel/singleton_class"
+require "active_support/core_ext/module/delegation"
 
 module ActiveSupport
   class Deprecation
     module InstanceDelegator # :nodoc:
       def self.included(base)
         base.extend(ClassMethods)
+        base.singleton_class.prepend(OverrideDelegators)
         base.public_class_method :new
       end
 
@@ -19,6 +22,18 @@ module ActiveSupport
           singleton_class.delegate(method_name, to: :instance)
         end
       end
+
+      module OverrideDelegators # :nodoc:
+        def warn(message = nil, callstack = nil)
+          callstack ||= caller_locations(2)
+          super
+        end
+
+        def deprecation_warning(deprecated_method_name, message = nil, caller_backtrace = nil)
+          caller_backtrace ||= caller_locations(2)
+          super
+        end
+      end
     end
   end
 end
diff --git a/activesupport/lib/active_support/deprecation/method_wrappers.rb b/activesupport/lib/active_support/deprecation/method_wrappers.rb
index f5ea6669ce..5be893d281 100644
--- a/activesupport/lib/active_support/deprecation/method_wrappers.rb
+++ b/activesupport/lib/active_support/deprecation/method_wrappers.rb
@@ -1,14 +1,14 @@
-require 'active_support/core_ext/module/aliasing'
-require 'active_support/core_ext/array/extract_options'
+# frozen_string_literal: true
+
+require "active_support/core_ext/module/aliasing"
+require "active_support/core_ext/array/extract_options"
 
 module ActiveSupport
   class Deprecation
     module MethodWrapper
       # Declare that a method has been deprecated.
       #
-      #   module Fred
-      #     extend self
-      #
+      #   class Fred
       #     def aaa; end
       #     def bbb; end
       #     def ccc; end
@@ -18,17 +18,17 @@ module ActiveSupport
       #
       # Using the default deprecator:
       #   ActiveSupport::Deprecation.deprecate_methods(Fred, :aaa, bbb: :zzz, ccc: 'use Bar#ccc instead')
-      #   # => [:aaa, :bbb, :ccc]
+      #   # => Fred
       #
-      #   Fred.aaa
+      #   Fred.new.aaa
       #   # DEPRECATION WARNING: aaa is deprecated and will be removed from Rails 5.1. (called from irb_binding at (irb):10)
       #   # => nil
       #
-      #   Fred.bbb
+      #   Fred.new.bbb
       #   # DEPRECATION WARNING: bbb is deprecated and will be removed from Rails 5.1 (use zzz instead). (called from irb_binding at (irb):11)
       #   # => nil
       #
-      #   Fred.ccc
+      #   Fred.new.ccc
       #   # DEPRECATION WARNING: ccc is deprecated and will be removed from Rails 5.1 (use Bar#ccc instead). (called from irb_binding at (irb):12)
       #   # => nil
       #
@@ -37,7 +37,7 @@ module ActiveSupport
       #   ActiveSupport::Deprecation.deprecate_methods(Fred, ddd: :zzz, deprecator: custom_deprecator)
       #   # => [:ddd]
       #
-      #   Fred.ddd
+      #   Fred.new.ddd
       #   DEPRECATION WARNING: ddd is deprecated and will be removed from MyGem next-release (use zzz instead). (called from irb_binding at (irb):15)
       #   # => nil
       #
@@ -46,7 +46,7 @@ module ActiveSupport
       #   custom_deprecator.deprecate_methods(Fred, eee: :zzz)
       #   # => [:eee]
       #
-      #   Fred.eee
+      #   Fred.new.eee
       #   DEPRECATION WARNING: eee is deprecated and will be removed from MyGem next-release (use zzz instead). (called from irb_binding at (irb):18)
       #   # => nil
       def deprecate_methods(target_module, *method_names)
@@ -60,6 +60,13 @@ module ActiveSupport
               deprecator.deprecation_warning(method_name, options[method_name])
               super(*args, &block)
             end
+
+            case
+            when target_module.protected_method_defined?(method_name)
+              protected method_name
+            when target_module.private_method_defined?(method_name)
+              private method_name
+            end
           end
         end
 
diff --git a/activesupport/lib/active_support/deprecation/proxy_wrappers.rb b/activesupport/lib/active_support/deprecation/proxy_wrappers.rb
index 0cb2d4d22e..896c0d2d8e 100644
--- a/activesupport/lib/active_support/deprecation/proxy_wrappers.rb
+++ b/activesupport/lib/active_support/deprecation/proxy_wrappers.rb
@@ -1,4 +1,6 @@
-require 'active_support/inflector/methods'
+# frozen_string_literal: true
+
+require "active_support/core_ext/regexp"
 
 module ActiveSupport
   class Deprecation
@@ -10,7 +12,7 @@ module ActiveSupport
         super
       end
 
-      instance_methods.each { |m| undef_method m unless m =~ /^__|^object_id$/ }
+      instance_methods.each { |m| undef_method m unless /^__|^object_id$/.match?(m) }
 
       # Don't give a deprecation warning on inspect since test/unit and error
       # logs rely on it for diagnostics.
@@ -111,7 +113,7 @@ module ActiveSupport
     #
     #   PLANETS = %w(mercury venus earth mars jupiter saturn uranus neptune pluto)
     #
-    #   (In a later update, the original implementation of `PLANETS` has been removed.)
+    #   # (In a later update, the original implementation of `PLANETS` has been removed.)
     #
     #   PLANETS_POST_2006 = %w(mercury venus earth mars jupiter saturn uranus neptune)
     #   PLANETS = ActiveSupport::Deprecation::DeprecatedConstantProxy.new('PLANETS', 'PLANETS_POST_2006')
@@ -121,10 +123,13 @@ module ActiveSupport
     #        (Backtrace information…)
     #        ["Mercury", "Venus", "Earth", "Mars", "Jupiter", "Saturn", "Uranus", "Neptune"]
     class DeprecatedConstantProxy < DeprecationProxy
-      def initialize(old_const, new_const, deprecator = ActiveSupport::Deprecation.instance)
+      def initialize(old_const, new_const, deprecator = ActiveSupport::Deprecation.instance, message: "#{old_const} is deprecated! Use #{new_const} instead.")
+        require "active_support/inflector/methods"
+
         @old_const = old_const
         @new_const = new_const
         @deprecator = deprecator
+        @message = message
       end
 
       # Returns the class of the new constant.
@@ -142,7 +147,7 @@ module ActiveSupport
         end
 
         def warn(callstack, called, args)
-          @deprecator.warn("#{@old_const} is deprecated! Use #{@new_const} instead.", callstack)
+          @deprecator.warn(@message, callstack)
         end
     end
   end
diff --git a/activesupport/lib/active_support/deprecation/reporting.rb b/activesupport/lib/active_support/deprecation/reporting.rb
index de5b233679..242e21b782 100644
--- a/activesupport/lib/active_support/deprecation/reporting.rb
+++ b/activesupport/lib/active_support/deprecation/reporting.rb
@@ -1,4 +1,6 @@
-require 'rbconfig'
+# frozen_string_literal: true
+
+require "rbconfig"
 
 module ActiveSupport
   class Deprecation
@@ -18,7 +20,7 @@ module ActiveSupport
 
         callstack ||= caller_locations(2)
         deprecation_message(callstack, message).tap do |m|
-          behavior.each { |b| b.call(m, callstack) }
+          behavior.each { |b| b.call(m, callstack, deprecation_horizon, gem_name) }
         end
       end
 
@@ -48,17 +50,17 @@ module ActiveSupport
       private
         # Outputs a deprecation warning message
         #
-        #   ActiveSupport::Deprecation.deprecated_method_warning(:method_name)
+        #   deprecated_method_warning(:method_name)
         #   # => "method_name is deprecated and will be removed from Rails #{deprecation_horizon}"
-        #   ActiveSupport::Deprecation.deprecated_method_warning(:method_name, :another_method)
+        #   deprecated_method_warning(:method_name, :another_method)
         #   # => "method_name is deprecated and will be removed from Rails #{deprecation_horizon} (use another_method instead)"
-        #   ActiveSupport::Deprecation.deprecated_method_warning(:method_name, "Optional message")
+        #   deprecated_method_warning(:method_name, "Optional message")
         #   # => "method_name is deprecated and will be removed from Rails #{deprecation_horizon} (Optional message)"
         def deprecated_method_warning(method_name, message = nil)
           warning = "#{method_name} is deprecated and will be removed from #{gem_name} #{deprecation_horizon}"
           case message
-            when Symbol then "#{warning} (use #{message} instead)"
-            when String then "#{warning} (#{message})"
+          when Symbol then "#{warning} (use #{message} instead)"
+          when String then "#{warning} (#{message})"
             else warning
           end
         end
@@ -102,10 +104,10 @@ module ActiveSupport
           end
         end
 
-        RAILS_GEM_ROOT = File.expand_path("../../../../..", __FILE__) + "/"
+        RAILS_GEM_ROOT = File.expand_path("../../../..", __dir__)
 
         def ignored_callstack(path)
-          path.start_with?(RAILS_GEM_ROOT) || path.start_with?(RbConfig::CONFIG['rubylibdir'])
+          path.start_with?(RAILS_GEM_ROOT) || path.start_with?(RbConfig::CONFIG["rubylibdir"])
         end
     end
   end
diff --git a/activesupport/lib/active_support/descendants_tracker.rb b/activesupport/lib/active_support/descendants_tracker.rb
index 27861e01d0..a4cee788b6 100644
--- a/activesupport/lib/active_support/descendants_tracker.rb
+++ b/activesupport/lib/active_support/descendants_tracker.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActiveSupport
   # This module provides an internal implementation to track descendants
   # which is faster than iterating through ObjectSpace.
diff --git a/activesupport/lib/active_support/digest.rb b/activesupport/lib/active_support/digest.rb
new file mode 100644
index 0000000000..fba10fbdcf
--- /dev/null
+++ b/activesupport/lib/active_support/digest.rb
@@ -0,0 +1,20 @@
+# frozen_string_literal: true
+
+module ActiveSupport
+  class Digest #:nodoc:
+    class <<self
+      def hash_digest_class
+        @hash_digest_class ||= ::Digest::MD5
+      end
+
+      def hash_digest_class=(klass)
+        raise ArgumentError, "#{klass} is expected to implement hexdigest class method" unless klass.respond_to?(:hexdigest)
+        @hash_digest_class = klass
+      end
+
+      def hexdigest(arg)
+        hash_digest_class.hexdigest(arg)[0...32]
+      end
+    end
+  end
+end
diff --git a/activesupport/lib/active_support/duration.rb b/activesupport/lib/active_support/duration.rb
index 47d09f4f5a..fe1058762b 100644
--- a/activesupport/lib/active_support/duration.rb
+++ b/activesupport/lib/active_support/duration.rb
@@ -1,5 +1,10 @@
-require 'active_support/core_ext/array/conversions'
-require 'active_support/core_ext/object/acts_like'
+# frozen_string_literal: true
+
+require "active_support/core_ext/array/conversions"
+require "active_support/core_ext/module/delegation"
+require "active_support/core_ext/object/acts_like"
+require "active_support/core_ext/string/filters"
+require "active_support/deprecation"
 
 module ActiveSupport
   # Provides accurate date and time measurements using Date#advance and
@@ -7,22 +12,237 @@ module ActiveSupport
   #
   #   1.month.ago       # equivalent to Time.now.advance(months: -1)
   class Duration
+    class Scalar < Numeric #:nodoc:
+      attr_reader :value
+      delegate :to_i, :to_f, :to_s, to: :value
+
+      def initialize(value)
+        @value = value
+      end
+
+      def coerce(other)
+        [Scalar.new(other), self]
+      end
+
+      def -@
+        Scalar.new(-value)
+      end
+
+      def <=>(other)
+        if Scalar === other || Duration === other
+          value <=> other.value
+        elsif Numeric === other
+          value <=> other
+        else
+          nil
+        end
+      end
+
+      def +(other)
+        if Duration === other
+          seconds   = value + other.parts[:seconds]
+          new_parts = other.parts.merge(seconds: seconds)
+          new_value = value + other.value
+
+          Duration.new(new_value, new_parts)
+        else
+          calculate(:+, other)
+        end
+      end
+
+      def -(other)
+        if Duration === other
+          seconds   = value - other.parts[:seconds]
+          new_parts = other.parts.map { |part, other_value| [part, -other_value] }.to_h
+          new_parts = new_parts.merge(seconds: seconds)
+          new_value = value - other.value
+
+          Duration.new(new_value, new_parts)
+        else
+          calculate(:-, other)
+        end
+      end
+
+      def *(other)
+        if Duration === other
+          new_parts = other.parts.map { |part, other_value| [part, value * other_value] }.to_h
+          new_value = value * other.value
+
+          Duration.new(new_value, new_parts)
+        else
+          calculate(:*, other)
+        end
+      end
+
+      def /(other)
+        if Duration === other
+          value / other.value
+        else
+          calculate(:/, other)
+        end
+      end
+
+      def %(other)
+        if Duration === other
+          Duration.build(value % other.value)
+        else
+          calculate(:%, other)
+        end
+      end
+
+      private
+        def calculate(op, other)
+          if Scalar === other
+            Scalar.new(value.public_send(op, other.value))
+          elsif Numeric === other
+            Scalar.new(value.public_send(op, other))
+          else
+            raise_type_error(other)
+          end
+        end
+
+        def raise_type_error(other)
+          raise TypeError, "no implicit conversion of #{other.class} into #{self.class}"
+        end
+    end
+
+    SECONDS_PER_MINUTE = 60
+    SECONDS_PER_HOUR   = 3600
+    SECONDS_PER_DAY    = 86400
+    SECONDS_PER_WEEK   = 604800
+    SECONDS_PER_MONTH  = 2629746  # 1/12 of a gregorian year
+    SECONDS_PER_YEAR   = 31556952 # length of a gregorian year (365.2425 days)
+
+    PARTS_IN_SECONDS = {
+      seconds: 1,
+      minutes: SECONDS_PER_MINUTE,
+      hours:   SECONDS_PER_HOUR,
+      days:    SECONDS_PER_DAY,
+      weeks:   SECONDS_PER_WEEK,
+      months:  SECONDS_PER_MONTH,
+      years:   SECONDS_PER_YEAR
+    }.freeze
+
+    PARTS = [:years, :months, :weeks, :days, :hours, :minutes, :seconds].freeze
+
     attr_accessor :value, :parts
 
-    autoload :ISO8601Parser,     'active_support/duration/iso8601_parser'
-    autoload :ISO8601Serializer, 'active_support/duration/iso8601_serializer'
+    autoload :ISO8601Parser,     "active_support/duration/iso8601_parser"
+    autoload :ISO8601Serializer, "active_support/duration/iso8601_serializer"
+
+    class << self
+      # Creates a new Duration from string formatted according to ISO 8601 Duration.
+      #
+      # See {ISO 8601}[https://en.wikipedia.org/wiki/ISO_8601#Durations] for more information.
+      # This method allows negative parts to be present in pattern.
+      # If invalid string is provided, it will raise +ActiveSupport::Duration::ISO8601Parser::ParsingError+.
+      def parse(iso8601duration)
+        parts = ISO8601Parser.new(iso8601duration).parse!
+        new(calculate_total_seconds(parts), parts)
+      end
+
+      def ===(other) #:nodoc:
+        other.is_a?(Duration)
+      rescue ::NoMethodError
+        false
+      end
+
+      def seconds(value) #:nodoc:
+        new(value, [[:seconds, value]])
+      end
+
+      def minutes(value) #:nodoc:
+        new(value * SECONDS_PER_MINUTE, [[:minutes, value]])
+      end
+
+      def hours(value) #:nodoc:
+        new(value * SECONDS_PER_HOUR, [[:hours, value]])
+      end
+
+      def days(value) #:nodoc:
+        new(value * SECONDS_PER_DAY, [[:days, value]])
+      end
+
+      def weeks(value) #:nodoc:
+        new(value * SECONDS_PER_WEEK, [[:weeks, value]])
+      end
+
+      def months(value) #:nodoc:
+        new(value * SECONDS_PER_MONTH, [[:months, value]])
+      end
+
+      def years(value) #:nodoc:
+        new(value * SECONDS_PER_YEAR, [[:years, value]])
+      end
+
+      # Creates a new Duration from a seconds value that is converted
+      # to the individual parts:
+      #
+      #   ActiveSupport::Duration.build(31556952).parts # => {:years=>1}
+      #   ActiveSupport::Duration.build(2716146).parts  # => {:months=>1, :days=>1}
+      #
+      def build(value)
+        parts = {}
+        remainder = value.to_f
+
+        PARTS.each do |part|
+          unless part == :seconds
+            part_in_seconds = PARTS_IN_SECONDS[part]
+            parts[part] = remainder.div(part_in_seconds)
+            remainder = (remainder % part_in_seconds).round(9)
+          end
+        end
+
+        parts[:seconds] = remainder
+
+        new(value, parts)
+      end
+
+      private
+
+        def calculate_total_seconds(parts)
+          parts.inject(0) do |total, (part, value)|
+            total + value * PARTS_IN_SECONDS[part]
+          end
+        end
+    end
 
     def initialize(value, parts) #:nodoc:
-      @value, @parts = value, parts
+      @value, @parts = value, parts.to_h
+      @parts.default = 0
+      @parts.reject! { |k, v| v.zero? }
+    end
+
+    def coerce(other) #:nodoc:
+      if Scalar === other
+        [other, self]
+      else
+        [Scalar.new(other), self]
+      end
+    end
+
+    # Compares one Duration with another or a Numeric to this Duration.
+    # Numeric values are treated as seconds.
+    def <=>(other)
+      if Duration === other
+        value <=> other.value
+      elsif Numeric === other
+        value <=> other
+      end
     end
 
     # Adds another Duration or a Numeric to this Duration. Numeric values
     # are treated as seconds.
     def +(other)
       if Duration === other
-        Duration.new(value + other.value, @parts + other.parts)
+        parts = @parts.dup
+        other.parts.each do |(key, value)|
+          parts[key] += value
+        end
+        Duration.new(value + other.value, parts)
       else
-        Duration.new(value + other, @parts + [[:seconds, other]])
+        seconds = @parts[:seconds] + other
+        Duration.new(value + other, @parts.merge(seconds: seconds))
       end
     end
 
@@ -32,8 +252,44 @@ module ActiveSupport
       self + (-other)
     end
 
+    # Multiplies this Duration by a Numeric and returns a new Duration.
+    def *(other)
+      if Scalar === other || Duration === other
+        Duration.new(value * other.value, parts.map { |type, number| [type, number * other.value] })
+      elsif Numeric === other
+        Duration.new(value * other, parts.map { |type, number| [type, number * other] })
+      else
+        raise_type_error(other)
+      end
+    end
+
+    # Divides this Duration by a Numeric and returns a new Duration.
+    def /(other)
+      if Scalar === other
+        Duration.new(value / other.value, parts.map { |type, number| [type, number / other.value] })
+      elsif Duration === other
+        value / other.value
+      elsif Numeric === other
+        Duration.new(value / other, parts.map { |type, number| [type, number / other] })
+      else
+        raise_type_error(other)
+      end
+    end
+
+    # Returns the modulo of this Duration by another Duration or Numeric.
+    # Numeric values are treated as seconds.
+    def %(other)
+      if Duration === other || Scalar === other
+        Duration.build(value % other.value)
+      elsif Numeric === other
+        Duration.build(value % other)
+      else
+        raise_type_error(other)
+      end
+    end
+
     def -@ #:nodoc:
-      Duration.new(-value, parts.map { |type,number| [type, -number] })
+      Duration.new(-value, parts.map { |type, number| [type, -number] })
     end
 
     def is_a?(klass) #:nodoc:
@@ -70,14 +326,14 @@ module ActiveSupport
     #   1.day.to_i      # => 86400
     #
     # Note that this conversion makes some assumptions about the
-    # duration of some periods, e.g. months are always 30 days
-    # and years are 365.25 days:
+    # duration of some periods, e.g. months are always 1/12 of year
+    # and years are 365.2425 days:
     #
-    #   # equivalent to 30.days.to_i
-    #   1.month.to_i    # => 2592000
+    #   # equivalent to (1.year / 12).to_i
+    #   1.month.to_i    # => 2629746
     #
-    #   # equivalent to 365.25.days.to_i
-    #   1.year.to_i     # => 31557600
+    #   # equivalent to 365.2425.days.to_i
+    #   1.year.to_i     # => 31556952
     #
     # In such cases, Ruby's core
     # Date[http://ruby-doc.org/stdlib/libdoc/date/rdoc/Date.html] and
@@ -97,18 +353,13 @@ module ActiveSupport
       @value.hash
     end
 
-    def self.===(other) #:nodoc:
-      other.is_a?(Duration)
-    rescue ::NoMethodError
-      false
-    end
-
     # Calculates a new Time or Date that is as far in the future
     # as this Duration represents.
     def since(time = ::Time.current)
       sum(1, time)
     end
     alias :from_now :since
+    alias :after :since
 
     # Calculates a new Time or Date that is as far in the past
     # as this Duration represents.
@@ -116,12 +367,15 @@ module ActiveSupport
       sum(-1, time)
     end
     alias :until :ago
+    alias :before :ago
 
     def inspect #:nodoc:
+      return "0 seconds" if parts.empty?
+
       parts.
-        reduce(::Hash.new(0)) { |h,(l,r)| h[l] += r; h }.
-        sort_by {|unit,  _ | [:years, :months, :weeks, :days, :hours, :minutes, :seconds].index(unit)}.
-        map     {|unit, val| "#{val} #{val == 1 ? unit.to_s.chop : unit.to_s}"}.
+        reduce(::Hash.new(0)) { |h, (l, r)| h[l] += r; h }.
+        sort_by { |unit,  _ | PARTS.index(unit) }.
+        map     { |unit, val| "#{val} #{val == 1 ? unit.to_s.chop : unit.to_s}" }.
         to_sentence(locale: ::I18n.default_locale)
     end
 
@@ -129,33 +383,16 @@ module ActiveSupport
       to_i
     end
 
-    def respond_to_missing?(method, include_private=false) #:nodoc:
-      @value.respond_to?(method, include_private)
-    end
-
-    # Creates a new Duration from string formatted according to ISO 8601 Duration.
-    #
-    # See {ISO 8601}[http://en.wikipedia.org/wiki/ISO_8601#Durations] for more information.
-    # This method allows negative parts to be present in pattern.
-    # If invalid string is provided, it will raise +ActiveSupport::Duration::ISO8601Parser::ParsingError+.
-    def self.parse(iso8601duration)
-      parts = ISO8601Parser.new(iso8601duration).parse!
-      time  = ::Time.current
-      new(time.advance(parts) - time, parts)
-    end
-
     # Build ISO 8601 Duration string for this duration.
     # The +precision+ parameter can be used to limit seconds' precision of duration.
     def iso8601(precision: nil)
       ISO8601Serializer.new(self, precision: precision).serialize
     end
 
-    delegate :<=>, to: :value
-
-    protected
+    private
 
-      def sum(sign, time = ::Time.current) #:nodoc:
-        parts.inject(time) do |t,(type,number)|
+      def sum(sign, time = ::Time.current)
+        parts.inject(time) do |t, (type, number)|
           if t.acts_like?(:time) || t.acts_like?(:date)
             if type == :seconds
               t.since(sign * number)
@@ -172,10 +409,16 @@ module ActiveSupport
         end
       end
 
-    private
+      def respond_to_missing?(method, _)
+        value.respond_to?(method)
+      end
+
+      def method_missing(method, *args, &block)
+        value.public_send(method, *args, &block)
+      end
 
-      def method_missing(method, *args, &block) #:nodoc:
-        value.send(method, *args, &block)
+      def raise_type_error(other)
+        raise TypeError, "no implicit conversion of #{other.class} into #{self.class}"
       end
   end
 end
diff --git a/activesupport/lib/active_support/duration/iso8601_parser.rb b/activesupport/lib/active_support/duration/iso8601_parser.rb
index 07af58ad99..1847eeaa86 100644
--- a/activesupport/lib/active_support/duration/iso8601_parser.rb
+++ b/activesupport/lib/active_support/duration/iso8601_parser.rb
@@ -1,18 +1,21 @@
-require 'strscan'
+# frozen_string_literal: true
+
+require "strscan"
+require "active_support/core_ext/regexp"
 
 module ActiveSupport
   class Duration
     # Parses a string formatted according to ISO 8601 Duration into the hash.
     #
-    # See {ISO 8601}[http://en.wikipedia.org/wiki/ISO_8601#Durations] for more information.
+    # See {ISO 8601}[https://en.wikipedia.org/wiki/ISO_8601#Durations] for more information.
     #
     # This parser allows negative parts to be present in pattern.
     class ISO8601Parser # :nodoc:
       class ParsingError < ::ArgumentError; end
 
       PERIOD_OR_COMMA = /\.|,/
-      PERIOD = '.'.freeze
-      COMMA = ','.freeze
+      PERIOD = ".".freeze
+      COMMA = ",".freeze
 
       SIGN_MARKER = /\A\-|\+|/
       DATE_MARKER = /P/
@@ -20,8 +23,8 @@ module ActiveSupport
       DATE_COMPONENT = /(\-?\d+(?:[.,]\d+)?)(Y|M|D|W)/
       TIME_COMPONENT = /(\-?\d+(?:[.,]\d+)?)(H|M|S)/
 
-      DATE_TO_PART = { 'Y' => :years, 'M' => :months, 'W' => :weeks, 'D' => :days }
-      TIME_TO_PART = { 'H' => :hours, 'M' => :minutes, 'S' => :seconds }
+      DATE_TO_PART = { "Y" => :years, "M" => :months, "W" => :weeks, "D" => :days }
+      TIME_TO_PART = { "H" => :hours, "M" => :minutes, "S" => :seconds }
 
       DATE_COMPONENTS = [:years, :months, :days]
       TIME_COMPONENTS = [:hours, :minutes, :seconds]
@@ -39,36 +42,36 @@ module ActiveSupport
       def parse!
         while !finished?
           case mode
-            when :start
-              if scan(SIGN_MARKER)
-                self.sign = (scanner.matched == '-') ? -1 : 1
-                self.mode = :sign
-              else
-                raise_parsing_error
-              end
-
-            when :sign
-              if scan(DATE_MARKER)
-                self.mode = :date
-              else
-                raise_parsing_error
-              end
-
-            when :date
-              if scan(TIME_MARKER)
-                self.mode = :time
-              elsif scan(DATE_COMPONENT)
-                parts[DATE_TO_PART[scanner[2]]] = number * sign
-              else
-                raise_parsing_error
-              end
-
-            when :time
-              if scan(TIME_COMPONENT)
-                parts[TIME_TO_PART[scanner[2]]] = number * sign
-              else
-                raise_parsing_error
-              end
+          when :start
+            if scan(SIGN_MARKER)
+              self.sign = (scanner.matched == "-") ? -1 : 1
+              self.mode = :sign
+            else
+              raise_parsing_error
+            end
+
+          when :sign
+            if scan(DATE_MARKER)
+              self.mode = :date
+            else
+              raise_parsing_error
+            end
+
+          when :date
+            if scan(TIME_MARKER)
+              self.mode = :time
+            elsif scan(DATE_COMPONENT)
+              parts[DATE_TO_PART[scanner[2]]] = number * sign
+            else
+              raise_parsing_error
+            end
+
+          when :time
+            if scan(TIME_COMPONENT)
+              parts[TIME_TO_PART[scanner[2]]] = number * sign
+            else
+              raise_parsing_error
+            end
 
           end
         end
@@ -79,44 +82,44 @@ module ActiveSupport
 
       private
 
-      def finished?
-        scanner.eos?
-      end
+        def finished?
+          scanner.eos?
+        end
 
-      # Parses number which can be a float with either comma or period.
-      def number
-        scanner[1] =~ PERIOD_OR_COMMA ? scanner[1].tr(COMMA, PERIOD).to_f : scanner[1].to_i
-      end
+        # Parses number which can be a float with either comma or period.
+        def number
+          PERIOD_OR_COMMA.match?(scanner[1]) ? scanner[1].tr(COMMA, PERIOD).to_f : scanner[1].to_i
+        end
 
-      def scan(pattern)
-        scanner.scan(pattern)
-      end
+        def scan(pattern)
+          scanner.scan(pattern)
+        end
 
-      def raise_parsing_error(reason = nil)
-        raise ParsingError, "Invalid ISO 8601 duration: #{scanner.string.inspect} #{reason}".strip
-      end
+        def raise_parsing_error(reason = nil)
+          raise ParsingError, "Invalid ISO 8601 duration: #{scanner.string.inspect} #{reason}".strip
+        end
 
-      # Checks for various semantic errors as stated in ISO 8601 standard.
-      def validate!
-        raise_parsing_error('is empty duration') if parts.empty?
+        # Checks for various semantic errors as stated in ISO 8601 standard.
+        def validate!
+          raise_parsing_error("is empty duration") if parts.empty?
 
-        # Mixing any of Y, M, D with W is invalid.
-        if parts.key?(:weeks) && (parts.keys & DATE_COMPONENTS).any?
-          raise_parsing_error('mixing weeks with other date parts not allowed')
-        end
+          # Mixing any of Y, M, D with W is invalid.
+          if parts.key?(:weeks) && (parts.keys & DATE_COMPONENTS).any?
+            raise_parsing_error("mixing weeks with other date parts not allowed")
+          end
 
-        # Specifying an empty T part is invalid.
-        if mode == :time && (parts.keys & TIME_COMPONENTS).empty?
-          raise_parsing_error('time part marker is present but time part is empty')
-        end
+          # Specifying an empty T part is invalid.
+          if mode == :time && (parts.keys & TIME_COMPONENTS).empty?
+            raise_parsing_error("time part marker is present but time part is empty")
+          end
 
-        fractions = parts.values.reject(&:zero?).select { |a| (a % 1) != 0 }
-        unless fractions.empty? || (fractions.size == 1 && fractions.last == @parts.values.reject(&:zero?).last)
-          raise_parsing_error '(only last part can be fractional)'
-        end
+          fractions = parts.values.reject(&:zero?).select { |a| (a % 1) != 0 }
+          unless fractions.empty? || (fractions.size == 1 && fractions.last == @parts.values.reject(&:zero?).last)
+            raise_parsing_error "(only last part can be fractional)"
+          end
 
-        return true
-      end
+          true
+        end
     end
   end
 end
diff --git a/activesupport/lib/active_support/duration/iso8601_serializer.rb b/activesupport/lib/active_support/duration/iso8601_serializer.rb
index 05c6a083a9..bb177ae5b7 100644
--- a/activesupport/lib/active_support/duration/iso8601_serializer.rb
+++ b/activesupport/lib/active_support/duration/iso8601_serializer.rb
@@ -1,10 +1,12 @@
-require 'active_support/core_ext/object/blank'
-require 'active_support/core_ext/hash/transform_values'
+# frozen_string_literal: true
+
+require "active_support/core_ext/object/blank"
+require "active_support/core_ext/hash/transform_values"
 
 module ActiveSupport
   class Duration
     # Serializes duration to string according to ISO 8601 Duration format.
-    class ISO8601Serializer
+    class ISO8601Serializer # :nodoc:
       def initialize(duration, precision: nil)
         @duration = duration
         @precision = precision
@@ -12,19 +14,21 @@ module ActiveSupport
 
       # Builds and returns output string.
       def serialize
-        output = 'P'
         parts, sign = normalize
+        return "PT0S".freeze if parts.empty?
+
+        output = "P".dup
         output << "#{parts[:years]}Y"   if parts.key?(:years)
         output << "#{parts[:months]}M"  if parts.key?(:months)
         output << "#{parts[:weeks]}W"   if parts.key?(:weeks)
         output << "#{parts[:days]}D"    if parts.key?(:days)
-        time = ''
+        time = "".dup
         time << "#{parts[:hours]}H"     if parts.key?(:hours)
         time << "#{parts[:minutes]}M"   if parts.key?(:minutes)
         if parts.key?(:seconds)
           time << "#{sprintf(@precision ? "%0.0#{@precision}f" : '%g', parts[:seconds])}S"
         end
-        output << "T#{time}"  if time.present?
+        output << "T#{time}" unless time.empty?
         "#{sign}#{output}"
       end
 
@@ -35,13 +39,13 @@ module ActiveSupport
         # Zero parts are removed as not significant.
         # If all parts are negative it will negate all of them and return minus as a sign.
         def normalize
-          parts = @duration.parts.each_with_object(Hash.new(0)) do |(k,v),p|
+          parts = @duration.parts.each_with_object(Hash.new(0)) do |(k, v), p|
             p[k] += v  unless v.zero?
           end
           # If all parts are negative - let's make a negative duration
-          sign = ''
+          sign = ""
           if parts.values.all? { |v| v < 0 }
-            sign = '-'
+            sign = "-"
             parts.transform_values!(&:-@)
           end
           [parts, sign]
diff --git a/activesupport/lib/active_support/encrypted_configuration.rb b/activesupport/lib/active_support/encrypted_configuration.rb
new file mode 100644
index 0000000000..dab953d5d5
--- /dev/null
+++ b/activesupport/lib/active_support/encrypted_configuration.rb
@@ -0,0 +1,49 @@
+# frozen_string_literal: true
+
+require "yaml"
+require "active_support/encrypted_file"
+require "active_support/ordered_options"
+require "active_support/core_ext/object/inclusion"
+require "active_support/core_ext/module/delegation"
+
+module ActiveSupport
+  class EncryptedConfiguration < EncryptedFile
+    delegate :[], :fetch, to: :config
+    delegate_missing_to :options
+
+    def initialize(config_path:, key_path:, env_key:, raise_if_missing_key:)
+      super content_path: config_path, key_path: key_path,
+        env_key: env_key, raise_if_missing_key: raise_if_missing_key
+    end
+
+    # Allow a config to be started without a file present
+    def read
+      super
+    rescue ActiveSupport::EncryptedFile::MissingContentError
+      ""
+    end
+
+    def write(contents)
+      deserialize(contents)
+
+      super
+    end
+
+    def config
+      @config ||= deserialize(read).deep_symbolize_keys
+    end
+
+    private
+      def options
+        @options ||= ActiveSupport::InheritableOptions.new(config)
+      end
+
+      def serialize(config)
+        config.present? ? YAML.dump(config) : ""
+      end
+
+      def deserialize(config)
+        config.present? ? YAML.load(config, content_path) : {}
+      end
+  end
+end
diff --git a/activesupport/lib/active_support/encrypted_file.rb b/activesupport/lib/active_support/encrypted_file.rb
new file mode 100644
index 0000000000..671b6b6a69
--- /dev/null
+++ b/activesupport/lib/active_support/encrypted_file.rb
@@ -0,0 +1,99 @@
+# frozen_string_literal: true
+
+require "pathname"
+require "active_support/message_encryptor"
+
+module ActiveSupport
+  class EncryptedFile
+    class MissingContentError < RuntimeError
+      def initialize(content_path)
+        super "Missing encrypted content file in #{content_path}."
+      end
+    end
+
+    class MissingKeyError < RuntimeError
+      def initialize(key_path:, env_key:)
+        super \
+          "Missing encryption key to decrypt file with. " +
+          "Ask your team for your master key and write it to #{key_path} or put it in the ENV['#{env_key}']."
+      end
+    end
+
+    CIPHER = "aes-128-gcm"
+
+    def self.generate_key
+      SecureRandom.hex(ActiveSupport::MessageEncryptor.key_len(CIPHER))
+    end
+
+
+    attr_reader :content_path, :key_path, :env_key, :raise_if_missing_key
+
+    def initialize(content_path:, key_path:, env_key:, raise_if_missing_key:)
+      @content_path, @key_path = Pathname.new(content_path), Pathname.new(key_path)
+      @env_key, @raise_if_missing_key = env_key, raise_if_missing_key
+    end
+
+    def key
+      read_env_key || read_key_file || handle_missing_key
+    end
+
+    def read
+      if !key.nil? && content_path.exist?
+        decrypt content_path.binread
+      else
+        raise MissingContentError, content_path
+      end
+    end
+
+    def write(contents)
+      IO.binwrite "#{content_path}.tmp", encrypt(contents)
+      FileUtils.mv "#{content_path}.tmp", content_path
+    end
+
+    def change(&block)
+      writing read, &block
+    end
+
+
+    private
+      def writing(contents)
+        tmp_file = "#{content_path.basename}.#{Process.pid}"
+        tmp_path = Pathname.new File.join(Dir.tmpdir, tmp_file)
+        tmp_path.binwrite contents
+
+        yield tmp_path
+
+        updated_contents = tmp_path.binread
+
+        write(updated_contents) if updated_contents != contents
+      ensure
+        FileUtils.rm(tmp_path) if tmp_path.exist?
+      end
+
+
+      def encrypt(contents)
+        encryptor.encrypt_and_sign contents
+      end
+
+      def decrypt(contents)
+        encryptor.decrypt_and_verify contents
+      end
+
+      def encryptor
+        @encryptor ||= ActiveSupport::MessageEncryptor.new([ key ].pack("H*"), cipher: CIPHER)
+      end
+
+
+      def read_env_key
+        ENV[env_key]
+      end
+
+      def read_key_file
+        key_path.binread.strip if key_path.exist?
+      end
+
+      def handle_missing_key
+        raise MissingKeyError, key_path: key_path, env_key: env_key if raise_if_missing_key
+      end
+  end
+end
diff --git a/activesupport/lib/active_support/evented_file_update_checker.rb b/activesupport/lib/active_support/evented_file_update_checker.rb
index a2dcf31132..97e982eb05 100644
--- a/activesupport/lib/active_support/evented_file_update_checker.rb
+++ b/activesupport/lib/active_support/evented_file_update_checker.rb
@@ -1,6 +1,8 @@
-require 'set'
-require 'pathname'
-require 'concurrent/atomic/atomic_boolean'
+# frozen_string_literal: true
+
+require "set"
+require "pathname"
+require "concurrent/atomic/atomic_boolean"
 
 module ActiveSupport
   # Allows you to "listen" to changes in a file system.
@@ -17,7 +19,7 @@ module ActiveSupport
   #
   # Example:
   #
-  #     checker = EventedFileUpdateChecker.new(["/tmp/foo"], -> { puts "changed" })
+  #     checker = ActiveSupport::EventedFileUpdateChecker.new(["/tmp/foo"]) { puts "changed" }
   #     checker.updated?
   #     # => false
   #     checker.execute_if_updated
@@ -32,6 +34,10 @@ module ActiveSupport
   #
   class EventedFileUpdateChecker #:nodoc: all
     def initialize(files, dirs = {}, &block)
+      unless block
+        raise ArgumentError, "A block is required to initialize an EventedFileUpdateChecker"
+      end
+
       @ph    = PathHelper.new
       @files = files.map { |f| @ph.xpath(f) }.to_set
 
@@ -52,7 +58,7 @@ module ActiveSupport
         # to our test suite. Thus, we lazy load it and disable warnings locally.
         silence_warnings do
           begin
-            require 'listen'
+            require "listen"
           rescue LoadError => e
             raise LoadError, "Could not load the 'listen' gem. Add `gem 'listen'` to the development group of your Gemfile", e.backtrace
           end
@@ -121,74 +127,79 @@ module ActiveSupport
         dtw.compact!
         dtw.uniq!
 
+        normalized_gem_paths = Gem.path.map { |path| File.join path, "" }
+        dtw = dtw.reject do |path|
+          normalized_gem_paths.any? { |gem_path| path.to_s.start_with?(gem_path) }
+        end
+
         @ph.filter_out_descendants(dtw)
       end
 
-    class PathHelper
-      def xpath(path)
-        Pathname.new(path).expand_path
-      end
+      class PathHelper
+        def xpath(path)
+          Pathname.new(path).expand_path
+        end
 
-      def normalize_extension(ext)
-        ext.to_s.sub(/\A\./, '')
-      end
+        def normalize_extension(ext)
+          ext.to_s.sub(/\A\./, "")
+        end
 
-      # Given a collection of Pathname objects returns the longest subpath
-      # common to all of them, or +nil+ if there is none.
-      def longest_common_subpath(paths)
-        return if paths.empty?
-
-        lcsp = Pathname.new(paths[0])
-
-        paths[1..-1].each do |path|
-          until ascendant_of?(lcsp, path)
-            if lcsp.root?
-              # If we get here a root directory is not an ascendant of path.
-              # This may happen if there are paths in different drives on
-              # Windows.
-              return
-            else
-              lcsp = lcsp.parent
+        # Given a collection of Pathname objects returns the longest subpath
+        # common to all of them, or +nil+ if there is none.
+        def longest_common_subpath(paths)
+          return if paths.empty?
+
+          lcsp = Pathname.new(paths[0])
+
+          paths[1..-1].each do |path|
+            until ascendant_of?(lcsp, path)
+              if lcsp.root?
+                # If we get here a root directory is not an ascendant of path.
+                # This may happen if there are paths in different drives on
+                # Windows.
+                return
+              else
+                lcsp = lcsp.parent
+              end
             end
           end
-        end
 
-        lcsp
-      end
+          lcsp
+        end
 
-      # Returns the deepest existing ascendant, which could be the argument itself.
-      def existing_parent(dir)
-        dir.ascend do |ascendant|
-          break ascendant if ascendant.directory?
+        # Returns the deepest existing ascendant, which could be the argument itself.
+        def existing_parent(dir)
+          dir.ascend do |ascendant|
+            break ascendant if ascendant.directory?
+          end
         end
-      end
 
-      # Filters out directories which are descendants of others in the collection (stable).
-      def filter_out_descendants(dirs)
-        return dirs if dirs.length < 2
+        # Filters out directories which are descendants of others in the collection (stable).
+        def filter_out_descendants(dirs)
+          return dirs if dirs.length < 2
 
-        dirs_sorted_by_nparts = dirs.sort_by { |dir| dir.each_filename.to_a.length }
-        descendants = []
+          dirs_sorted_by_nparts = dirs.sort_by { |dir| dir.each_filename.to_a.length }
+          descendants = []
 
-        until dirs_sorted_by_nparts.empty?
-          dir = dirs_sorted_by_nparts.shift
+          until dirs_sorted_by_nparts.empty?
+            dir = dirs_sorted_by_nparts.shift
 
-          dirs_sorted_by_nparts.reject! do |possible_descendant|
-            ascendant_of?(dir, possible_descendant) && descendants << possible_descendant
+            dirs_sorted_by_nparts.reject! do |possible_descendant|
+              ascendant_of?(dir, possible_descendant) && descendants << possible_descendant
+            end
           end
-        end
 
-        # Array#- preserves order.
-        dirs - descendants
-      end
+          # Array#- preserves order.
+          dirs - descendants
+        end
 
-      private
+        private
 
-        def ascendant_of?(base, other)
-          base != other && other.ascend do |ascendant|
-            break true if base == ascendant
+          def ascendant_of?(base, other)
+            base != other && other.ascend do |ascendant|
+              break true if base == ascendant
+            end
           end
-        end
-    end
+      end
   end
 end
diff --git a/activesupport/lib/active_support/execution_wrapper.rb b/activesupport/lib/active_support/execution_wrapper.rb
index 00c5745a25..f48c586cad 100644
--- a/activesupport/lib/active_support/execution_wrapper.rb
+++ b/activesupport/lib/active_support/execution_wrapper.rb
@@ -1,4 +1,6 @@
-require 'active_support/callbacks'
+# frozen_string_literal: true
+
+require "active_support/callbacks"
 
 module ActiveSupport
   class ExecutionWrapper
@@ -19,6 +21,23 @@ module ActiveSupport
       set_callback(:complete, *args, &block)
     end
 
+    RunHook = Struct.new(:hook) do # :nodoc:
+      def before(target)
+        hook_state = target.send(:hook_state)
+        hook_state[hook] = hook.run
+      end
+    end
+
+    CompleteHook = Struct.new(:hook) do # :nodoc:
+      def before(target)
+        hook_state = target.send(:hook_state)
+        if hook_state.key?(hook)
+          hook.complete hook_state[hook]
+        end
+      end
+      alias after before
+    end
+
     # Register an object to be invoked during both the +run+ and
     # +complete+ steps.
     #
@@ -29,19 +48,11 @@ module ActiveSupport
     # invoked in that situation.)
     def self.register_hook(hook, outer: false)
       if outer
-        run_args = [prepend: true]
-        complete_args = [:after]
+        to_run RunHook.new(hook), prepend: true
+        to_complete :after, CompleteHook.new(hook)
       else
-        run_args = complete_args = []
-      end
-
-      to_run(*run_args) do
-        hook_state[hook] = hook.run
-      end
-      to_complete(*complete_args) do
-        if hook_state.key?(hook)
-          hook.complete hook_state[hook]
-        end
+        to_run RunHook.new(hook)
+        to_complete CompleteHook.new(hook)
       end
     end
 
diff --git a/activesupport/lib/active_support/executor.rb b/activesupport/lib/active_support/executor.rb
index 602fb11a44..ce391b07ec 100644
--- a/activesupport/lib/active_support/executor.rb
+++ b/activesupport/lib/active_support/executor.rb
@@ -1,4 +1,6 @@
-require 'active_support/execution_wrapper'
+# frozen_string_literal: true
+
+require "active_support/execution_wrapper"
 
 module ActiveSupport
   class Executor < ExecutionWrapper
diff --git a/activesupport/lib/active_support/file_update_checker.rb b/activesupport/lib/active_support/file_update_checker.rb
index b5667b6ac8..1a0bb10815 100644
--- a/activesupport/lib/active_support/file_update_checker.rb
+++ b/activesupport/lib/active_support/file_update_checker.rb
@@ -1,4 +1,6 @@
-require 'active_support/core_ext/time/calculations'
+# frozen_string_literal: true
+
+require "active_support/core_ext/time/calculations"
 
 module ActiveSupport
   # FileUpdateChecker specifies the API used by Rails to watch files
@@ -38,6 +40,10 @@ module ActiveSupport
     # changes. The array of files and list of directories cannot be changed
     # after FileUpdateChecker has been initialized.
     def initialize(files, dirs = {}, &block)
+      unless block
+        raise ArgumentError, "A block is required to initialize a FileUpdateChecker"
+      end
+
       @files = files.freeze
       @glob  = compile_glob(dirs)
       @block = block
@@ -93,65 +99,65 @@ module ActiveSupport
 
     private
 
-    def watched
-      @watched || begin
-        all = @files.select { |f| File.exist?(f) }
-        all.concat(Dir[@glob]) if @glob
-        all
+      def watched
+        @watched || begin
+          all = @files.select { |f| File.exist?(f) }
+          all.concat(Dir[@glob]) if @glob
+          all
+        end
       end
-    end
 
-    def updated_at(paths)
-      @updated_at || max_mtime(paths) || Time.at(0)
-    end
+      def updated_at(paths)
+        @updated_at || max_mtime(paths) || Time.at(0)
+      end
 
-    # This method returns the maximum mtime of the files in +paths+, or +nil+
-    # if the array is empty.
-    #
-    # Files with a mtime in the future are ignored. Such abnormal situation
-    # can happen for example if the user changes the clock by hand. It is
-    # healthy to consider this edge case because with mtimes in the future
-    # reloading is not triggered.
-    def max_mtime(paths)
-      time_now = Time.now
-      max_mtime = nil
-
-      # Time comparisons are performed with #compare_without_coercion because
-      # AS redefines these operators in a way that is much slower and does not
-      # bring any benefit in this particular code.
+      # This method returns the maximum mtime of the files in +paths+, or +nil+
+      # if the array is empty.
       #
-      # Read t1.compare_without_coercion(t2) < 0 as t1 < t2.
-      paths.each do |path|
-        mtime = File.mtime(path)
-
-        next if time_now.compare_without_coercion(mtime) < 0
-
-        if max_mtime.nil? || max_mtime.compare_without_coercion(mtime) < 0
-          max_mtime = mtime
+      # Files with a mtime in the future are ignored. Such abnormal situation
+      # can happen for example if the user changes the clock by hand. It is
+      # healthy to consider this edge case because with mtimes in the future
+      # reloading is not triggered.
+      def max_mtime(paths)
+        time_now = Time.now
+        max_mtime = nil
+
+        # Time comparisons are performed with #compare_without_coercion because
+        # AS redefines these operators in a way that is much slower and does not
+        # bring any benefit in this particular code.
+        #
+        # Read t1.compare_without_coercion(t2) < 0 as t1 < t2.
+        paths.each do |path|
+          mtime = File.mtime(path)
+
+          next if time_now.compare_without_coercion(mtime) < 0
+
+          if max_mtime.nil? || max_mtime.compare_without_coercion(mtime) < 0
+            max_mtime = mtime
+          end
         end
-      end
 
-      max_mtime
-    end
+        max_mtime
+      end
 
-    def compile_glob(hash)
-      hash.freeze # Freeze so changes aren't accidentally pushed
-      return if hash.empty?
+      def compile_glob(hash)
+        hash.freeze # Freeze so changes aren't accidentally pushed
+        return if hash.empty?
 
-      globs = hash.map do |key, value|
-        "#{escape(key)}/**/*#{compile_ext(value)}"
+        globs = hash.map do |key, value|
+          "#{escape(key)}/**/*#{compile_ext(value)}"
+        end
+        "{#{globs.join(",")}}"
       end
-      "{#{globs.join(",")}}"
-    end
 
-    def escape(key)
-      key.gsub(',','\,')
-    end
+      def escape(key)
+        key.gsub(",", '\,')
+      end
 
-    def compile_ext(array)
-      array = Array(array)
-      return if array.empty?
-      ".{#{array.join(",")}}"
-    end
+      def compile_ext(array)
+        array = Array(array)
+        return if array.empty?
+        ".{#{array.join(",")}}"
+      end
   end
 end
diff --git a/activesupport/lib/active_support/gem_version.rb b/activesupport/lib/active_support/gem_version.rb
index 74f2d8dd4b..1e09adbb52 100644
--- a/activesupport/lib/active_support/gem_version.rb
+++ b/activesupport/lib/active_support/gem_version.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActiveSupport
   # Returns the version of the currently loaded Active Support as a <tt>Gem::Version</tt>.
   def self.gem_version
@@ -6,9 +8,9 @@ module ActiveSupport
 
   module VERSION
     MAJOR = 5
-    MINOR = 1
+    MINOR = 2
     TINY  = 0
-    PRE   = "alpha"
+    PRE   = "beta2"
 
     STRING = [MAJOR, MINOR, TINY, PRE].compact.join(".")
   end
diff --git a/activesupport/lib/active_support/gzip.rb b/activesupport/lib/active_support/gzip.rb
index b837c879bb..7ffa6d90a2 100644
--- a/activesupport/lib/active_support/gzip.rb
+++ b/activesupport/lib/active_support/gzip.rb
@@ -1,5 +1,7 @@
-require 'zlib'
-require 'stringio'
+# frozen_string_literal: true
+
+require "zlib"
+require "stringio"
 
 module ActiveSupport
   # A convenient wrapper for the zlib standard library that allows
@@ -9,7 +11,7 @@ module ActiveSupport
   #   # => "\x1F\x8B\b\x00o\x8D\xCDO\x00\x03K\xCE\xCF-(J-.V\xC8MU\x04\x00R>n\x83\f\x00\x00\x00"
   #
   #   ActiveSupport::Gzip.decompress(gzip)
-  #   # => "compress me!" 
+  #   # => "compress me!"
   module Gzip
     class Stream < StringIO
       def initialize(*)
@@ -21,11 +23,11 @@ module ActiveSupport
 
     # Decompresses a gzipped string.
     def self.decompress(source)
-      Zlib::GzipReader.new(StringIO.new(source)).read
+      Zlib::GzipReader.wrap(StringIO.new(source), &:read)
     end
 
     # Compresses a string using gzip.
-    def self.compress(source, level=Zlib::DEFAULT_COMPRESSION, strategy=Zlib::DEFAULT_STRATEGY)
+    def self.compress(source, level = Zlib::DEFAULT_COMPRESSION, strategy = Zlib::DEFAULT_STRATEGY)
       output = Stream.new
       gz = Zlib::GzipWriter.new(output, level, strategy)
       gz.write(source)
diff --git a/activesupport/lib/active_support/hash_with_indifferent_access.rb b/activesupport/lib/active_support/hash_with_indifferent_access.rb
index 03770a197c..2e2ed8a25d 100644
--- a/activesupport/lib/active_support/hash_with_indifferent_access.rb
+++ b/activesupport/lib/active_support/hash_with_indifferent_access.rb
@@ -1,5 +1,7 @@
-require 'active_support/core_ext/hash/keys'
-require 'active_support/core_ext/hash/reverse_merge'
+# frozen_string_literal: true
+
+require "active_support/core_ext/hash/keys"
+require "active_support/core_ext/hash/reverse_merge"
 
 module ActiveSupport
   # Implements a hash where keys <tt>:foo</tt> and <tt>"foo"</tt> are considered
@@ -40,6 +42,12 @@ module ActiveSupport
   #   rgb = { black: '#000000', white: '#FFFFFF' }.with_indifferent_access
   #
   # which may be handy.
+  #
+  # To access this class outside of Rails, require the core extension with:
+  #
+  #   require "active_support/core_ext/hash/indifferent_access"
+  #
+  # which will, in turn, require this file.
   class HashWithIndifferentAccess < Hash
     # Returns +true+ so that <tt>Array#extract_options!</tt> finds members of
     # this class.
@@ -68,25 +76,6 @@ module ActiveSupport
       end
     end
 
-    def default(*args)
-      arg_key = args.first
-
-      if include?(key = convert_key(arg_key))
-        self[key]
-      else
-        super
-      end
-    end
-
-    def self.new_from_hash_copying_default(hash)
-      ActiveSupport::Deprecation.warn(<<-MSG.squish)
-        `ActiveSupport::HashWithIndifferentAccess.new_from_hash_copying_default`
-        has been deprecated, and will be removed in Rails 5.1. The behavior of
-        this method is now identical to the behavior of `.new`.
-      MSG
-      new(hash)
-    end
-
     def self.[](*args)
       new.merge!(Hash[*args])
     end
@@ -161,7 +150,6 @@ module ActiveSupport
     alias_method :has_key?, :key?
     alias_method :member?, :key?
 
-
     # Same as <tt>Hash#[]</tt> where the key passed as argument can be
     # either a string or a symbol:
     #
@@ -189,6 +177,36 @@ module ActiveSupport
       super(convert_key(key), *extras)
     end
 
+    if Hash.new.respond_to?(:dig)
+      # Same as <tt>Hash#dig</tt> where the key passed as argument can be
+      # either a string or a symbol:
+      #
+      #   counters = ActiveSupport::HashWithIndifferentAccess.new
+      #   counters[:foo] = { bar: 1 }
+      #
+      #   counters.dig('foo', 'bar')     # => 1
+      #   counters.dig(:foo, :bar)       # => 1
+      #   counters.dig(:zoo)             # => nil
+      def dig(*args)
+        args[0] = convert_key(args[0]) if args.size > 0
+        super(*args)
+      end
+    end
+
+    # Same as <tt>Hash#default</tt> where the key passed as argument can be
+    # either a string or a symbol:
+    #
+    #   hash = ActiveSupport::HashWithIndifferentAccess.new(1)
+    #   hash.default                   # => 1
+    #
+    #   hash = ActiveSupport::HashWithIndifferentAccess.new { |hash, key| key }
+    #   hash.default                   # => nil
+    #   hash.default('foo')            # => 'foo'
+    #   hash.default(:foo)             # => 'foo'
+    def default(*args)
+      super(*args.map { |arg| convert_key(arg) })
+    end
+
     # Returns an array of the values at the specified indices:
     #
     #   hash = ActiveSupport::HashWithIndifferentAccess.new
@@ -199,13 +217,26 @@ module ActiveSupport
       indices.collect { |key| self[convert_key(key)] }
     end
 
+    # Returns an array of the values at the specified indices, but also
+    # raises an exception when one of the keys can't be found.
+    #
+    #   hash = ActiveSupport::HashWithIndifferentAccess.new
+    #   hash[:a] = 'x'
+    #   hash[:b] = 'y'
+    #   hash.fetch_values('a', 'b') # => ["x", "y"]
+    #   hash.fetch_values('a', 'c') { |key| 'z' } # => ["x", "z"]
+    #   hash.fetch_values('a', 'c') # => KeyError: key not found: "c"
+    def fetch_values(*indices, &block)
+      indices.collect { |key| fetch(key, &block) }
+    end if Hash.method_defined?(:fetch_values)
+
     # Returns a shallow copy of the hash.
     #
     #   hash = ActiveSupport::HashWithIndifferentAccess.new({ a: { b: 'b' } })
     #   dup  = hash.dup
     #   dup[:a][:c] = 'c'
     #
-    #   hash[:a][:c] # => nil
+    #   hash[:a][:c] # => "c"
     #   dup[:a][:c]  # => "c"
     def dup
       self.class.new(self).tap do |new_hash|
@@ -217,7 +248,7 @@ module ActiveSupport
     # modify the receiver but rather returns a new hash with indifferent
     # access with the result of the merge.
     def merge(hash, &block)
-      self.dup.update(hash, &block)
+      dup.update(hash, &block)
     end
 
     # Like +merge+ but the other way around: Merges the receiver into the
@@ -229,11 +260,13 @@ module ActiveSupport
     def reverse_merge(other_hash)
       super(self.class.new(other_hash))
     end
+    alias_method :with_defaults, :reverse_merge
 
     # Same semantics as +reverse_merge+ but modifies the receiver in-place.
     def reverse_merge!(other_hash)
-      replace(reverse_merge( other_hash ))
+      super(self.class.new(other_hash))
     end
+    alias_method :with_defaults!, :reverse_merge!
 
     # Replaces the contents of this hash with other_hash.
     #
@@ -268,6 +301,30 @@ module ActiveSupport
       dup.tap { |hash| hash.reject!(*args, &block) }
     end
 
+    def transform_values(*args, &block)
+      return to_enum(:transform_values) unless block_given?
+      dup.tap { |hash| hash.transform_values!(*args, &block) }
+    end
+
+    def transform_keys(*args, &block)
+      return to_enum(:transform_keys) unless block_given?
+      dup.tap { |hash| hash.transform_keys!(*args, &block) }
+    end
+
+    def slice(*keys)
+      keys.map! { |key| convert_key(key) }
+      self.class.new(super)
+    end
+
+    def slice!(*keys)
+      keys.map! { |key| convert_key(key) }
+      super
+    end
+
+    def compact
+      dup.tap(&:compact!)
+    end
+
     # Convert to a regular hash with string keys.
     def to_hash
       _new_hash = Hash.new
@@ -279,12 +336,12 @@ module ActiveSupport
       _new_hash
     end
 
-    protected
-      def convert_key(key)
+    private
+      def convert_key(key) # :doc:
         key.kind_of?(Symbol) ? key.to_s : key
       end
 
-      def convert_value(value, options = {})
+      def convert_value(value, options = {}) # :doc:
         if value.is_a? Hash
           if options[:for] == :to_hash
             value.to_hash
@@ -301,7 +358,7 @@ module ActiveSupport
         end
       end
 
-      def set_defaults(target)
+      def set_defaults(target) # :doc:
         if default_proc
           target.default_proc = default_proc.dup
         else
@@ -311,4 +368,6 @@ module ActiveSupport
   end
 end
 
+# :stopdoc:
+
 HashWithIndifferentAccess = ActiveSupport::HashWithIndifferentAccess
diff --git a/activesupport/lib/active_support/i18n.rb b/activesupport/lib/active_support/i18n.rb
index 6cc98191d4..d60b3eff30 100644
--- a/activesupport/lib/active_support/i18n.rb
+++ b/activesupport/lib/active_support/i18n.rb
@@ -1,13 +1,15 @@
-require 'active_support/core_ext/hash/deep_merge'
-require 'active_support/core_ext/hash/except'
-require 'active_support/core_ext/hash/slice'
+# frozen_string_literal: true
+
+require "active_support/core_ext/hash/deep_merge"
+require "active_support/core_ext/hash/except"
+require "active_support/core_ext/hash/slice"
 begin
-  require 'i18n'
+  require "i18n"
 rescue LoadError => e
   $stderr.puts "The i18n gem is not available. Please add it to your Gemfile and run bundle install"
   raise e
 end
-require 'active_support/lazy_load_hooks'
+require "active_support/lazy_load_hooks"
 
 ActiveSupport.run_load_hooks(:i18n)
-I18n.load_path << "#{File.dirname(__FILE__)}/locale/en.yml"
+I18n.load_path << File.expand_path("locale/en.yml", __dir__)
diff --git a/activesupport/lib/active_support/i18n_railtie.rb b/activesupport/lib/active_support/i18n_railtie.rb
index 6cc7c90c12..ce8bfbfd8c 100644
--- a/activesupport/lib/active_support/i18n_railtie.rb
+++ b/activesupport/lib/active_support/i18n_railtie.rb
@@ -1,7 +1,11 @@
+# frozen_string_literal: true
+
 require "active_support"
 require "active_support/file_update_checker"
 require "active_support/core_ext/array/wrap"
 
+# :enddoc:
+
 module I18n
   class Railtie < Rails::Railtie
     config.i18n = ActiveSupport::OrderedOptions.new
@@ -21,8 +25,6 @@ module I18n
       I18n::Railtie.initialize_i18n(app)
     end
 
-  protected
-
     @i18n_inited = false
 
     # Setup i18n configuration.
@@ -42,7 +44,7 @@ module I18n
         case setting
         when :railties_load_path
           reloadable_paths = value
-          app.config.i18n.load_path.unshift(*value.map(&:existent).flatten)
+          app.config.i18n.load_path.unshift(*value.flat_map(&:existent))
         when :load_path
           I18n.load_path += value
         else
@@ -58,7 +60,7 @@ module I18n
       directories = watched_dirs_with_extensions(reloadable_paths)
       reloader = app.config.file_watcher.new(I18n.load_path.dup, directories) do
         I18n.load_path.keep_if { |p| File.exist?(p) }
-        I18n.load_path |= reloadable_paths.map(&:existent).flatten
+        I18n.load_path |= reloadable_paths.flat_map(&:existent)
 
         I18n.reload!
       end
@@ -66,10 +68,6 @@ module I18n
       app.reloaders << reloader
       app.reloader.to_run do
         reloader.execute_if_updated { require_unload_lock! }
-        # TODO: remove the following line as soon as the return value of
-        # callbacks is ignored, that is, returning `false` does not
-        # display a deprecation warning or halts the callback chain.
-        true
       end
       reloader.execute
 
@@ -83,14 +81,15 @@ module I18n
     def self.init_fallbacks(fallbacks)
       include_fallbacks_module
 
-      args = case fallbacks
-      when ActiveSupport::OrderedOptions
-        [*(fallbacks[:defaults] || []) << fallbacks[:map]].compact
-      when Hash, Array
-        Array.wrap(fallbacks)
-      else # TrueClass
-        []
-      end
+      args = \
+        case fallbacks
+        when ActiveSupport::OrderedOptions
+          [*(fallbacks[:defaults] || []) << fallbacks[:map]].compact
+        when Hash, Array
+          Array.wrap(fallbacks)
+        else # TrueClass
+          []
+        end
 
       I18n.fallbacks = I18n::Locale::Fallbacks.new(*args)
     end
diff --git a/activesupport/lib/active_support/inflections.rb b/activesupport/lib/active_support/inflections.rb
index 2ca1124e76..baf1cb3038 100644
--- a/activesupport/lib/active_support/inflections.rb
+++ b/activesupport/lib/active_support/inflections.rb
@@ -1,4 +1,6 @@
-require 'active_support/inflector/inflections'
+# frozen_string_literal: true
+
+require "active_support/inflector/inflections"
 
 #--
 # Defines the standard inflection rules. These are the starting point for
@@ -8,8 +10,8 @@ require 'active_support/inflector/inflections'
 #++
 module ActiveSupport
   Inflector.inflections(:en) do |inflect|
-    inflect.plural(/$/, 's')
-    inflect.plural(/s$/i, 's')
+    inflect.plural(/$/, "s")
+    inflect.plural(/s$/i, "s")
     inflect.plural(/^(ax|test)is$/i, '\1es')
     inflect.plural(/(octop|vir)us$/i, '\1i')
     inflect.plural(/(octop|vir)i$/i, '\1i')
@@ -18,7 +20,7 @@ module ActiveSupport
     inflect.plural(/(buffal|tomat)o$/i, '\1oes')
     inflect.plural(/([ti])um$/i, '\1a')
     inflect.plural(/([ti])a$/i, '\1a')
-    inflect.plural(/sis$/i, 'ses')
+    inflect.plural(/sis$/i, "ses")
     inflect.plural(/(?:([^f])fe|([lr])f)$/i, '\1\2ves')
     inflect.plural(/(hive)$/i, '\1s')
     inflect.plural(/([^aeiouy]|qu)y$/i, '\1ies')
@@ -30,7 +32,7 @@ module ActiveSupport
     inflect.plural(/^(oxen)$/i, '\1')
     inflect.plural(/(quiz)$/i, '\1zes')
 
-    inflect.singular(/s$/i, '')
+    inflect.singular(/s$/i, "")
     inflect.singular(/(ss)$/i, '\1')
     inflect.singular(/(n)ews$/i, '\1ews')
     inflect.singular(/([ti])a$/i, '\1um')
@@ -58,12 +60,12 @@ module ActiveSupport
     inflect.singular(/(quiz)zes$/i, '\1')
     inflect.singular(/(database)s$/i, '\1')
 
-    inflect.irregular('person', 'people')
-    inflect.irregular('man', 'men')
-    inflect.irregular('child', 'children')
-    inflect.irregular('sex', 'sexes')
-    inflect.irregular('move', 'moves')
-    inflect.irregular('zombie', 'zombies')
+    inflect.irregular("person", "people")
+    inflect.irregular("man", "men")
+    inflect.irregular("child", "children")
+    inflect.irregular("sex", "sexes")
+    inflect.irregular("move", "moves")
+    inflect.irregular("zombie", "zombies")
 
     inflect.uncountable(%w(equipment information rice money species series fish sheep jeans police))
   end
diff --git a/activesupport/lib/active_support/inflector.rb b/activesupport/lib/active_support/inflector.rb
index 215a60eba7..d77f04c9c5 100644
--- a/activesupport/lib/active_support/inflector.rb
+++ b/activesupport/lib/active_support/inflector.rb
@@ -1,7 +1,9 @@
+# frozen_string_literal: true
+
 # in case active_support/inflector is required without the rest of active_support
-require 'active_support/inflector/inflections'
-require 'active_support/inflector/transliterate'
-require 'active_support/inflector/methods'
+require "active_support/inflector/inflections"
+require "active_support/inflector/transliterate"
+require "active_support/inflector/methods"
 
-require 'active_support/inflections'
-require 'active_support/core_ext/string/inflections'
+require "active_support/inflections"
+require "active_support/core_ext/string/inflections"
diff --git a/activesupport/lib/active_support/inflector/inflections.rb b/activesupport/lib/active_support/inflector/inflections.rb
index f3e52b48ac..0450a4be4c 100644
--- a/activesupport/lib/active_support/inflector/inflections.rb
+++ b/activesupport/lib/active_support/inflector/inflections.rb
@@ -1,6 +1,10 @@
-require 'concurrent/map'
-require 'active_support/core_ext/array/prepend_and_append'
-require 'active_support/i18n'
+# frozen_string_literal: true
+
+require "concurrent/map"
+require "active_support/core_ext/array/prepend_and_append"
+require "active_support/core_ext/regexp"
+require "active_support/i18n"
+require "active_support/deprecation"
 
 module ActiveSupport
   module Inflector
@@ -43,13 +47,14 @@ module ActiveSupport
         end
 
         def add(words)
-          self.concat(words.flatten.map(&:downcase))
-          @regex_array += self.map {|word|  to_regex(word) }
+          words = words.flatten.map(&:downcase)
+          concat(words)
+          @regex_array += words.map { |word| to_regex(word) }
           self
         end
 
         def uncountable?(str)
-          @regex_array.any? { |regex| regex === str }
+          @regex_array.any? { |regex| regex.match? str }
         end
 
         private
@@ -63,16 +68,21 @@ module ActiveSupport
       end
 
       attr_reader :plurals, :singulars, :uncountables, :humans, :acronyms, :acronym_regex
+      deprecate :acronym_regex
+
+      attr_reader :acronyms_camelize_regex, :acronyms_underscore_regex # :nodoc:
 
       def initialize
-        @plurals, @singulars, @uncountables, @humans, @acronyms, @acronym_regex = [], [], Uncountables.new, [], {}, /(?=a)b/
+        @plurals, @singulars, @uncountables, @humans, @acronyms = [], [], Uncountables.new, [], {}
+        define_acronym_regex_patterns
       end
 
       # Private, for the test suite.
       def initialize_dup(orig) # :nodoc:
-        %w(plurals singulars uncountables humans acronyms acronym_regex).each do |scope|
+        %w(plurals singulars uncountables humans acronyms).each do |scope|
           instance_variable_set("@#{scope}", orig.send(scope).dup)
         end
+        define_acronym_regex_patterns
       end
 
       # Specifies a new acronym. An acronym must be specified as it will appear
@@ -126,7 +136,7 @@ module ActiveSupport
       #   camelize 'mcdonald'   # => 'McDonald'
       def acronym(word)
         @acronyms[word.downcase] = word
-        @acronym_regex = /#{@acronyms.values.join("|")}/
+        define_acronym_regex_patterns
       end
 
       # Specifies a new pluralization rule and its replacement. The rule can
@@ -215,12 +225,20 @@ module ActiveSupport
       #   clear :plurals
       def clear(scope = :all)
         case scope
-          when :all
-            @plurals, @singulars, @uncountables, @humans = [], [], Uncountables.new, []
+        when :all
+          @plurals, @singulars, @uncountables, @humans = [], [], Uncountables.new, []
           else
-            instance_variable_set "@#{scope}", []
+          instance_variable_set "@#{scope}", []
         end
       end
+
+      private
+
+        def define_acronym_regex_patterns
+          @acronym_regex             = @acronyms.empty? ? /(?=a)b/ : /#{@acronyms.values.join("|")}/
+          @acronyms_camelize_regex   = /^(?:#{@acronym_regex}(?=\b|[A-Z_])|\w)/
+          @acronyms_underscore_regex = /(?:(?<=([A-Za-z\d]))|\b)(#{@acronym_regex})(?=\b|[^a-z])/
+        end
     end
 
     # Yields a singleton instance of Inflector::Inflections so you can specify
diff --git a/activesupport/lib/active_support/inflector/methods.rb b/activesupport/lib/active_support/inflector/methods.rb
index f94e12e14f..60eeaa77cb 100644
--- a/activesupport/lib/active_support/inflector/methods.rb
+++ b/activesupport/lib/active_support/inflector/methods.rb
@@ -1,4 +1,7 @@
-require 'active_support/inflections'
+# frozen_string_literal: true
+
+require "active_support/inflections"
+require "active_support/core_ext/regexp"
 
 module ActiveSupport
   # The Inflector transforms words from singular to plural, class names to table
@@ -27,7 +30,7 @@ module ActiveSupport
     #   pluralize('CamelOctopus')     # => "CamelOctopi"
     #   pluralize('ley', :es)         # => "leyes"
     def pluralize(word, locale = :en)
-      apply_inflections(word, inflections(locale).plurals)
+      apply_inflections(word, inflections(locale).plurals, locale)
     end
 
     # The reverse of #pluralize, returns the singular form of a word in a
@@ -44,7 +47,7 @@ module ActiveSupport
     #   singularize('CamelOctopi')      # => "CamelOctopus"
     #   singularize('leyes', :es)       # => "ley"
     def singularize(word, locale = :en)
-      apply_inflections(word, inflections(locale).singulars)
+      apply_inflections(word, inflections(locale).singulars, locale)
     end
 
     # Converts strings to UpperCamelCase.
@@ -68,10 +71,10 @@ module ActiveSupport
       if uppercase_first_letter
         string = string.sub(/^[a-z\d]*/) { |match| inflections.acronyms[match] || match.capitalize }
       else
-        string = string.sub(/^(?:#{inflections.acronym_regex}(?=\b|[A-Z_])|\w)/) { |match| match.downcase }
+        string = string.sub(inflections.acronyms_camelize_regex) { |match| match.downcase }
       end
       string.gsub!(/(?:_|(\/))([a-z\d]*)/i) { "#{$1}#{inflections.acronyms[$2] || $2.capitalize}" }
-      string.gsub!('/'.freeze, '::'.freeze)
+      string.gsub!("/".freeze, "::".freeze)
       string
     end
 
@@ -87,9 +90,9 @@ module ActiveSupport
     #
     #   camelize(underscore('SSLError'))  # => "SslError"
     def underscore(camel_cased_word)
-      return camel_cased_word unless camel_cased_word =~ /[A-Z-]|::/
-      word = camel_cased_word.to_s.gsub('::'.freeze, '/'.freeze)
-      word.gsub!(/(?:(?<=([A-Za-z\d]))|\b)(#{inflections.acronym_regex})(?=\b|[^a-z])/) { "#{$1 && '_'.freeze }#{$2.downcase}" }
+      return camel_cased_word unless /[A-Z-]|::/.match?(camel_cased_word)
+      word = camel_cased_word.to_s.gsub("::".freeze, "/".freeze)
+      word.gsub!(inflections.acronyms_underscore_regex) { "#{$1 && '_'.freeze }#{$2.downcase}" }
       word.gsub!(/([A-Z\d]+)([A-Z][a-z])/, '\1_\2'.freeze)
       word.gsub!(/([a-z\d])([A-Z])/, '\1_\2'.freeze)
       word.tr!("-".freeze, "_".freeze)
@@ -107,33 +110,38 @@ module ActiveSupport
     # * Replaces underscores with spaces, if any.
     # * Downcases all words except acronyms.
     # * Capitalizes the first word.
-    #
     # The capitalization of the first word can be turned off by setting the
     # +:capitalize+ option to false (default is true).
     #
-    #   humanize('employee_salary')              # => "Employee salary"
-    #   humanize('author_id')                    # => "Author"
-    #   humanize('author_id', capitalize: false) # => "author"
-    #   humanize('_id')                          # => "Id"
+    # The trailing '_id' can be kept and capitalized by setting the
+    # optional parameter +keep_id_suffix+ to true (default is false).
+    #
+    #   humanize('employee_salary')                  # => "Employee salary"
+    #   humanize('author_id')                        # => "Author"
+    #   humanize('author_id', capitalize: false)     # => "author"
+    #   humanize('_id')                              # => "Id"
+    #   humanize('author_id', keep_id_suffix: true)  # => "Author Id"
     #
     # If "SSL" was defined to be an acronym:
     #
     #   humanize('ssl_error') # => "SSL error"
     #
-    def humanize(lower_case_and_underscored_word, options = {})
+    def humanize(lower_case_and_underscored_word, capitalize: true, keep_id_suffix: false)
       result = lower_case_and_underscored_word.to_s.dup
 
       inflections.humans.each { |(rule, replacement)| break if result.sub!(rule, replacement) }
 
-      result.sub!(/\A_+/, ''.freeze)
-      result.sub!(/_id\z/, ''.freeze)
-      result.tr!('_'.freeze, ' '.freeze)
+      result.sub!(/\A_+/, "".freeze)
+      unless keep_id_suffix
+        result.sub!(/_id\z/, "".freeze)
+      end
+      result.tr!("_".freeze, " ".freeze)
 
       result.gsub!(/([a-z\d]*)/i) do |match|
-        "#{inflections.acronyms[match] || match.downcase}"
+        "#{inflections.acronyms[match.downcase] || match.downcase}"
       end
 
-      if options.fetch(:capitalize, true)
+      if capitalize
         result.sub!(/\A\w/) { |match| match.upcase }
       end
 
@@ -146,21 +154,28 @@ module ActiveSupport
     #   upcase_first('w')                 # => "W"
     #   upcase_first('')                  # => ""
     def upcase_first(string)
-      string.length > 0 ? string[0].upcase.concat(string[1..-1]) : ''
+      string.length > 0 ? string[0].upcase.concat(string[1..-1]) : ""
     end
 
     # Capitalizes all the words and replaces some characters in the string to
     # create a nicer looking title. +titleize+ is meant for creating pretty
     # output. It is not used in the Rails internals.
     #
+    # The trailing '_id','Id'.. can be kept and capitalized by setting the
+    # optional parameter +keep_id_suffix+ to true.
+    # By default, this parameter is false.
+    #
     # +titleize+ is also aliased as +titlecase+.
     #
-    #   titleize('man from the boondocks')   # => "Man From The Boondocks"
-    #   titleize('x-men: the last stand')    # => "X Men: The Last Stand"
-    #   titleize('TheManWithoutAPast')       # => "The Man Without A Past"
-    #   titleize('raiders_of_the_lost_ark')  # => "Raiders Of The Lost Ark"
-    def titleize(word)
-      humanize(underscore(word)).gsub(/\b(?<!['’`])[a-z]/) { |match| match.capitalize }
+    #   titleize('man from the boondocks')                       # => "Man From The Boondocks"
+    #   titleize('x-men: the last stand')                        # => "X Men: The Last Stand"
+    #   titleize('TheManWithoutAPast')                           # => "The Man Without A Past"
+    #   titleize('raiders_of_the_lost_ark')                      # => "Raiders Of The Lost Ark"
+    #   titleize('string_ending_with_id', keep_id_suffix: true)  # => "String Ending With Id"
+    def titleize(word, keep_id_suffix: false)
+      humanize(underscore(word), keep_id_suffix: keep_id_suffix).gsub(/\b(?<!\w['’`])[a-z]/) do |match|
+        match.capitalize
+      end
     end
 
     # Creates the name of a table like Rails does for models to table names.
@@ -185,28 +200,28 @@ module ActiveSupport
     #   classify('calculus')     # => "Calculus"
     def classify(table_name)
       # strip out any leading schema name
-      camelize(singularize(table_name.to_s.sub(/.*\./, ''.freeze)))
+      camelize(singularize(table_name.to_s.sub(/.*\./, "".freeze)))
     end
 
     # Replaces underscores with dashes in the string.
     #
     #   dasherize('puni_puni') # => "puni-puni"
     def dasherize(underscored_word)
-      underscored_word.tr('_'.freeze, '-'.freeze)
+      underscored_word.tr("_".freeze, "-".freeze)
     end
 
     # Removes the module part from the expression in the string.
     #
-    #   demodulize('ActiveRecord::CoreExtensions::String::Inflections') # => "Inflections"
-    #   demodulize('Inflections')                                       # => "Inflections"
-    #   demodulize('::Inflections')                                     # => "Inflections"
-    #   demodulize('')                                                  # => ""
+    #   demodulize('ActiveSupport::Inflector::Inflections') # => "Inflections"
+    #   demodulize('Inflections')                           # => "Inflections"
+    #   demodulize('::Inflections')                         # => "Inflections"
+    #   demodulize('')                                      # => ""
     #
     # See also #deconstantize.
     def demodulize(path)
       path = path.to_s
-      if i = path.rindex('::')
-        path[(i+2)..-1]
+      if i = path.rindex("::")
+        path[(i + 2)..-1]
       else
         path
       end
@@ -222,7 +237,7 @@ module ActiveSupport
     #
     # See also #demodulize.
     def deconstantize(path)
-      path.to_s[0, path.rindex('::') || 0] # implementation based on the one in facets' Module#spacename
+      path.to_s[0, path.rindex("::") || 0] # implementation based on the one in facets' Module#spacename
     end
 
     # Creates a foreign key name from a class name.
@@ -238,8 +253,8 @@ module ActiveSupport
 
     # Tries to find a constant with the name specified in the argument string.
     #
-    #   'Module'.constantize   # => Module
-    #   'Foo::Bar'.constantize # => Foo::Bar
+    #   constantize('Module')   # => Module
+    #   constantize('Foo::Bar') # => Foo::Bar
     #
     # The name is assumed to be the one of a top-level constant, no matter
     # whether it starts with "::" or not. No lexical context is taken into
@@ -248,14 +263,14 @@ module ActiveSupport
     #   C = 'outside'
     #   module M
     #     C = 'inside'
-    #     C               # => 'inside'
-    #     'C'.constantize # => 'outside', same as ::C
+    #     C                # => 'inside'
+    #     constantize('C') # => 'outside', same as ::C
     #   end
     #
     # NameError is raised when the name is not in CamelCase or the constant is
     # unknown.
     def constantize(camel_cased_word)
-      names = camel_cased_word.split('::'.freeze)
+      names = camel_cased_word.split("::".freeze)
 
       # Trigger a built-in NameError exception including the ill-formed constant in the message.
       Object.const_get(camel_cased_word) if names.empty?
@@ -273,7 +288,7 @@ module ActiveSupport
 
           # Go down the ancestors to check if it is owned directly. The check
           # stops when we reach Object or the end of ancestors tree.
-          constant = constant.ancestors.inject do |const, ancestor|
+          constant = constant.ancestors.inject(constant) do |const, ancestor|
             break const    if ancestor == Object
             break ancestor if ancestor.const_defined?(name, false)
             const
@@ -313,7 +328,7 @@ module ActiveSupport
       raise if e.name && !(camel_cased_word.to_s.split("::").include?(e.name.to_s) ||
         e.name.to_s == camel_cased_word.to_s)
     rescue ArgumentError => e
-      raise unless e.message =~ /not missing constant #{const_regexp(camel_cased_word)}\!$/
+      raise unless /not missing constant #{const_regexp(camel_cased_word)}!$/.match?(e.message)
     end
 
     # Returns the suffix that should be added to a number to denote the position
@@ -332,9 +347,9 @@ module ActiveSupport
         "th"
       else
         case abs_number % 10
-          when 1; "st"
-          when 2; "nd"
-          when 3; "rd"
+        when 1; "st"
+        when 2; "nd"
+        when 3; "rd"
           else    "th"
         end
       end
@@ -355,36 +370,39 @@ module ActiveSupport
 
     private
 
-    # Mounts a regular expression, returned as a string to ease interpolation,
-    # that will match part by part the given constant.
-    #
-    #   const_regexp("Foo::Bar::Baz") # => "Foo(::Bar(::Baz)?)?"
-    #   const_regexp("::")            # => "::"
-    def const_regexp(camel_cased_word) #:nodoc:
-      parts = camel_cased_word.split("::".freeze)
+      # Mounts a regular expression, returned as a string to ease interpolation,
+      # that will match part by part the given constant.
+      #
+      #   const_regexp("Foo::Bar::Baz") # => "Foo(::Bar(::Baz)?)?"
+      #   const_regexp("::")            # => "::"
+      def const_regexp(camel_cased_word)
+        parts = camel_cased_word.split("::".freeze)
 
-      return Regexp.escape(camel_cased_word) if parts.blank?
+        return Regexp.escape(camel_cased_word) if parts.blank?
 
-      last  = parts.pop
+        last = parts.pop
 
-      parts.reverse.inject(last) do |acc, part|
-        part.empty? ? acc : "#{part}(::#{acc})?"
+        parts.reverse.inject(last) do |acc, part|
+          part.empty? ? acc : "#{part}(::#{acc})?"
+        end
       end
-    end
-
-    # Applies inflection rules for +singularize+ and +pluralize+.
-    #
-    #  apply_inflections('post', inflections.plurals)    # => "posts"
-    #  apply_inflections('posts', inflections.singulars) # => "post"
-    def apply_inflections(word, rules)
-      result = word.to_s.dup
 
-      if word.empty? || inflections.uncountables.uncountable?(result)
-        result
-      else
-        rules.each { |(rule, replacement)| break if result.sub!(rule, replacement) }
-        result
+      # Applies inflection rules for +singularize+ and +pluralize+.
+      #
+      # If passed an optional +locale+ parameter, the uncountables will be
+      # found for that locale.
+      #
+      #  apply_inflections('post', inflections.plurals, :en)    # => "posts"
+      #  apply_inflections('posts', inflections.singulars, :en) # => "post"
+      def apply_inflections(word, rules, locale = :en)
+        result = word.to_s.dup
+
+        if word.empty? || inflections(locale).uncountables.uncountable?(result)
+          result
+        else
+          rules.each { |(rule, replacement)| break if result.sub!(rule, replacement) }
+          result
+        end
       end
-    end
   end
 end
diff --git a/activesupport/lib/active_support/inflector/transliterate.rb b/activesupport/lib/active_support/inflector/transliterate.rb
index 871cfb8a72..6f2ca4999c 100644
--- a/activesupport/lib/active_support/inflector/transliterate.rb
+++ b/activesupport/lib/active_support/inflector/transliterate.rb
@@ -1,9 +1,10 @@
-require 'active_support/core_ext/string/multibyte'
-require 'active_support/i18n'
+# frozen_string_literal: true
+
+require "active_support/core_ext/string/multibyte"
+require "active_support/i18n"
 
 module ActiveSupport
   module Inflector
-
     # Replaces non-ASCII characters with an ASCII approximation, or if none
     # exists, a replacement character which defaults to "?".
     #
@@ -58,32 +59,37 @@ module ActiveSupport
     #   transliterate('Jürgen')
     #   # => "Juergen"
     def transliterate(string, replacement = "?".freeze)
-      I18n.transliterate(ActiveSupport::Multibyte::Unicode.normalize(
-        ActiveSupport::Multibyte::Unicode.tidy_bytes(string), :c),
-          :replacement => replacement)
+      raise ArgumentError, "Can only transliterate strings. Received #{string.class.name}" unless string.is_a?(String)
+
+      I18n.transliterate(
+        ActiveSupport::Multibyte::Unicode.normalize(
+          ActiveSupport::Multibyte::Unicode.tidy_bytes(string), :c),
+        replacement: replacement)
     end
 
     # Replaces special characters in a string so that it may be used as part of
     # a 'pretty' URL.
     #
     #   parameterize("Donald E. Knuth") # => "donald-e-knuth"
-    #   parameterize("^trés|Jolie-- ")  # => "tres-jolie"
+    #   parameterize("^très|Jolie-- ")  # => "tres-jolie"
     #
-    # To use a custom separator, override the `separator` argument.
+    # To use a custom separator, override the +separator+ argument.
     #
     #  parameterize("Donald E. Knuth", separator: '_') # => "donald_e_knuth"
-    #  parameterize("^trés|Jolie-- ", separator: '_')  # => "tres_jolie"
+    #  parameterize("^très|Jolie__ ", separator: '_')  # => "tres_jolie"
     #
-    # To preserve the case of the characters in a string, use the `preserve_case` argument.
+    # To preserve the case of the characters in a string, use the +preserve_case+ argument.
     #
     #   parameterize("Donald E. Knuth", preserve_case: true) # => "Donald-E-Knuth"
-    #   parameterize("^trés|Jolie-- ", preserve_case: true) # => "tres-Jolie"
+    #   parameterize("^très|Jolie-- ", preserve_case: true) # => "tres-Jolie"
     #
-    def parameterize(string, sep = :unused, separator: '-', preserve_case: false)
-      unless sep == :unused
-        ActiveSupport::Deprecation.warn("Passing the separator argument as a positional parameter is deprecated and will soon be removed. Use `separator: '#{sep}'` instead.")
-        separator = sep
-      end
+    # It preserves dashes and underscores unless they are used as separators:
+    #
+    #  parameterize("^très|Jolie__ ")                 # => "tres-jolie__"
+    #  parameterize("^très|Jolie-- ", separator: "_") # => "tres_jolie--"
+    #  parameterize("^très_Jolie-- ", separator: ".") # => "tres_jolie--"
+    #
+    def parameterize(string, separator: "-", preserve_case: false)
       # Replace accented chars with their ASCII equivalents.
       parameterized_string = transliterate(string)
 
@@ -102,9 +108,9 @@ module ActiveSupport
         # No more than one of the separator in a row.
         parameterized_string.gsub!(re_duplicate_separator, separator)
         # Remove leading/trailing separator.
-        parameterized_string.gsub!(re_leading_trailing_separator, ''.freeze)
+        parameterized_string.gsub!(re_leading_trailing_separator, "".freeze)
       end
-      
+
       parameterized_string.downcase! unless preserve_case
       parameterized_string
     end
diff --git a/activesupport/lib/active_support/json.rb b/activesupport/lib/active_support/json.rb
index 3e1d9b1d33..d7887175c0 100644
--- a/activesupport/lib/active_support/json.rb
+++ b/activesupport/lib/active_support/json.rb
@@ -1,2 +1,4 @@
-require 'active_support/json/decoding'
-require 'active_support/json/encoding'
+# frozen_string_literal: true
+
+require "active_support/json/decoding"
+require "active_support/json/encoding"
diff --git a/activesupport/lib/active_support/json/decoding.rb b/activesupport/lib/active_support/json/decoding.rb
index 2932954f03..8c0e016dc5 100644
--- a/activesupport/lib/active_support/json/decoding.rb
+++ b/activesupport/lib/active_support/json/decoding.rb
@@ -1,6 +1,8 @@
-require 'active_support/core_ext/module/attribute_accessors'
-require 'active_support/core_ext/module/delegation'
-require 'json'
+# frozen_string_literal: true
+
+require "active_support/core_ext/module/attribute_accessors"
+require "active_support/core_ext/module/delegation"
+require "json"
 
 module ActiveSupport
   # Look for and parse json strings that look like ISO 8601 times.
@@ -8,7 +10,8 @@ module ActiveSupport
 
   module JSON
     # matches YAML-formatted dates
-    DATE_REGEX = /^(?:\d{4}-\d{2}-\d{2}|\d{4}-\d{1,2}-\d{1,2}[T \t]+\d{1,2}:\d{2}:\d{2}(\.[0-9]*)?(([ \t]*)Z|[-+]\d{2}?(:\d{2})?))$/
+    DATE_REGEX = /^\d{4}-\d{2}-\d{2}$/
+    DATETIME_REGEX = /^(?:\d{4}-\d{2}-\d{2}|\d{4}-\d{1,2}-\d{1,2}[T \t]+\d{1,2}:\d{2}:\d{2}(\.[0-9]*)?(([ \t]*)Z|[-+]\d{2}?(:\d{2})?)?)$/
 
     class << self
       # Parses a JSON string (JavaScript Object Notation) into a hash.
@@ -48,7 +51,13 @@ module ActiveSupport
           nil
         when DATE_REGEX
           begin
-            DateTime.parse(data)
+            Date.parse(data)
+          rescue ArgumentError
+            data
+          end
+        when DATETIME_REGEX
+          begin
+            Time.zone.parse(data)
           rescue ArgumentError
             data
           end
diff --git a/activesupport/lib/active_support/json/encoding.rb b/activesupport/lib/active_support/json/encoding.rb
index 031c5e9339..1339c75ffe 100644
--- a/activesupport/lib/active_support/json/encoding.rb
+++ b/activesupport/lib/active_support/json/encoding.rb
@@ -1,5 +1,7 @@
-require 'active_support/core_ext/object/json'
-require 'active_support/core_ext/module/delegation'
+# frozen_string_literal: true
+
+require "active_support/core_ext/object/json"
+require "active_support/core_ext/module/delegation"
 
 module ActiveSupport
   class << self
@@ -7,7 +9,7 @@ module ActiveSupport
       :time_precision, :time_precision=,
       :escape_html_entities_in_json, :escape_html_entities_in_json=,
       :json_encoder, :json_encoder=,
-      :to => :'ActiveSupport::JSON::Encoding'
+      to: :'ActiveSupport::JSON::Encoding'
   end
 
   module JSON
@@ -40,9 +42,9 @@ module ActiveSupport
           ESCAPED_CHARS = {
             "\u2028" => '\u2028',
             "\u2029" => '\u2029',
-            '>'      => '\u003e',
-            '<'      => '\u003c',
-            '&'      => '\u0026',
+            ">"      => '\u003e',
+            "<"      => '\u003c',
+            "&"      => '\u0026',
             }
 
           ESCAPE_REGEX_WITH_HTML_ENTITIES = /[\u2028\u2029><&]/u
@@ -68,7 +70,8 @@ module ActiveSupport
             :ESCAPE_REGEX_WITHOUT_HTML_ENTITIES, :EscapedString
 
           # Convert an object into a "JSON-ready" representation composed of
-          # primitives like Hash, Array, String, Numeric, and true/false/nil.
+          # primitives like Hash, Array, String, Numeric,
+          # and +true+/+false+/+nil+.
           # Recursively calls #as_json to the object to recursively build a
           # fully JSON-ready object.
           #
@@ -84,7 +87,7 @@ module ActiveSupport
             when String
               EscapedString.new(value)
             when Numeric, NilClass, TrueClass, FalseClass
-              value
+              value.as_json
             when Hash
               Hash[value.map { |k, v| [jsonify(k), jsonify(v)] }]
             when Array
diff --git a/activesupport/lib/active_support/key_generator.rb b/activesupport/lib/active_support/key_generator.rb
index 7f73f9ddfc..78f7d7ca8d 100644
--- a/activesupport/lib/active_support/key_generator.rb
+++ b/activesupport/lib/active_support/key_generator.rb
@@ -1,5 +1,7 @@
-require 'concurrent/map'
-require 'openssl'
+# frozen_string_literal: true
+
+require "concurrent/map"
+require "openssl"
 
 module ActiveSupport
   # KeyGenerator is a simple wrapper around OpenSSL's implementation of PBKDF2.
@@ -17,7 +19,7 @@ module ActiveSupport
     # Returns a derived key suitable for use.  The default key_size is chosen
     # to be compatible with the default settings of ActiveSupport::MessageVerifier.
     # i.e. OpenSSL::Digest::SHA1#block_length
-    def generate_key(salt, key_size=64)
+    def generate_key(salt, key_size = 64)
       OpenSSL::PKCS5.pbkdf2_hmac_sha1(@secret, salt, @iterations, key_size)
     end
   end
@@ -31,11 +33,9 @@ module ActiveSupport
       @cache_keys = Concurrent::Map.new
     end
 
-    # Returns a derived key suitable for use.  The default key_size is chosen
-    # to be compatible with the default settings of ActiveSupport::MessageVerifier.
-    # i.e. OpenSSL::Digest::SHA1#block_length
-    def generate_key(salt, key_size=64)
-      @cache_keys["#{salt}#{key_size}"] ||= @key_generator.generate_key(salt, key_size)
+    # Returns a derived key suitable for use.
+    def generate_key(*args)
+      @cache_keys[args.join] ||= @key_generator.generate_key(*args)
     end
   end
 
@@ -53,21 +53,21 @@ module ActiveSupport
 
     private
 
-    # To prevent users from using something insecure like "Password" we make sure that the
-    # secret they've provided is at least 30 characters in length.
-    def ensure_secret_secure(secret)
-      if secret.blank?
-        raise ArgumentError, "A secret is required to generate an integrity hash " \
-          "for cookie session data. Set a secret_key_base of at least " \
-          "#{SECRET_MIN_LENGTH} characters in config/secrets.yml."
-      end
+      # To prevent users from using something insecure like "Password" we make sure that the
+      # secret they've provided is at least 30 characters in length.
+      def ensure_secret_secure(secret)
+        if secret.blank?
+          raise ArgumentError, "A secret is required to generate an integrity hash " \
+            "for cookie session data. Set a secret_key_base of at least " \
+            "#{SECRET_MIN_LENGTH} characters in via `bin/rails credentials:edit`."
+        end
 
-      if secret.length < SECRET_MIN_LENGTH
-        raise ArgumentError, "Secret should be something secure, " \
-          "like \"#{SecureRandom.hex(16)}\". The value you " \
-          "provided, \"#{secret}\", is shorter than the minimum length " \
-          "of #{SECRET_MIN_LENGTH} characters."
+        if secret.length < SECRET_MIN_LENGTH
+          raise ArgumentError, "Secret should be something secure, " \
+            "like \"#{SecureRandom.hex(16)}\". The value you " \
+            "provided, \"#{secret}\", is shorter than the minimum length " \
+            "of #{SECRET_MIN_LENGTH} characters."
+        end
       end
-    end
   end
 end
diff --git a/activesupport/lib/active_support/lazy_load_hooks.rb b/activesupport/lib/active_support/lazy_load_hooks.rb
index e2b8f0f648..dc8080c469 100644
--- a/activesupport/lib/active_support/lazy_load_hooks.rb
+++ b/activesupport/lib/active_support/lazy_load_hooks.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActiveSupport
   # lazy_load_hooks allows Rails to lazily load a lot of components and thus
   # making the app boot faster. Because of this feature now there is no need to
@@ -15,34 +17,62 @@ module ActiveSupport
   #     end
   #   end
   #
-  # When the entirety of +activerecord/lib/active_record/base.rb+ has been
+  # When the entirety of +ActiveRecord::Base+ has been
   # evaluated then +run_load_hooks+ is invoked. The very last line of
-  # +activerecord/lib/active_record/base.rb+ is:
+  # +ActiveRecord::Base+ is:
   #
   #   ActiveSupport.run_load_hooks(:active_record, ActiveRecord::Base)
-  @load_hooks = Hash.new { |h,k| h[k] = [] }
-  @loaded = Hash.new { |h,k| h[k] = [] }
-
-  def self.on_load(name, options = {}, &block)
-    @loaded[name].each do |base|
-      execute_hook(base, options, block)
+  module LazyLoadHooks
+    def self.extended(base) # :nodoc:
+      base.class_eval do
+        @load_hooks = Hash.new { |h, k| h[k] = [] }
+        @loaded     = Hash.new { |h, k| h[k] = [] }
+        @run_once   = Hash.new { |h, k| h[k] = [] }
+      end
     end
 
-    @load_hooks[name] << [block, options]
-  end
+    # Declares a block that will be executed when a Rails component is fully
+    # loaded.
+    #
+    # Options:
+    #
+    # * <tt>:yield</tt> - Yields the object that run_load_hooks to +block+.
+    # * <tt>:run_once</tt> - Given +block+ will run only once.
+    def on_load(name, options = {}, &block)
+      @loaded[name].each do |base|
+        execute_hook(name, base, options, block)
+      end
 
-  def self.execute_hook(base, options, block)
-    if options[:yield]
-      block.call(base)
-    else
-      base.instance_eval(&block)
+      @load_hooks[name] << [block, options]
     end
-  end
 
-  def self.run_load_hooks(name, base = Object)
-    @loaded[name] << base
-    @load_hooks[name].each do |hook, options|
-      execute_hook(base, options, hook)
+    def run_load_hooks(name, base = Object)
+      @loaded[name] << base
+      @load_hooks[name].each do |hook, options|
+        execute_hook(name, base, options, hook)
+      end
     end
+
+    private
+
+      def with_execution_control(name, block, once)
+        unless @run_once[name].include?(block)
+          @run_once[name] << block if once
+
+          yield
+        end
+      end
+
+      def execute_hook(name, base, options, block)
+        with_execution_control(name, block, options[:run_once]) do
+          if options[:yield]
+            block.call(base)
+          else
+            base.instance_eval(&block)
+          end
+        end
+      end
   end
+
+  extend LazyLoadHooks
 end
diff --git a/activesupport/lib/active_support/log_subscriber.rb b/activesupport/lib/active_support/log_subscriber.rb
index e782cd2d4b..0f7be06c8e 100644
--- a/activesupport/lib/active_support/log_subscriber.rb
+++ b/activesupport/lib/active_support/log_subscriber.rb
@@ -1,6 +1,8 @@
-require 'active_support/core_ext/module/attribute_accessors'
-require 'active_support/core_ext/class/attribute'
-require 'active_support/subscriber'
+# frozen_string_literal: true
+
+require "active_support/core_ext/module/attribute_accessors"
+require "active_support/core_ext/class/attribute"
+require "active_support/subscriber"
 
 module ActiveSupport
   # ActiveSupport::LogSubscriber is an object set to consume
@@ -49,8 +51,7 @@ module ActiveSupport
     CYAN    = "\e[36m"
     WHITE   = "\e[37m"
 
-    mattr_accessor :colorize_logging
-    self.colorize_logging = true
+    mattr_accessor :colorize_logging, default: true
 
     class << self
       def logger
@@ -81,11 +82,13 @@ module ActiveSupport
 
     def finish(name, id, payload)
       super if logger
-    rescue Exception => e
-      logger.error "Could not log #{name.inspect} event. #{e.class}: #{e.message} #{e.backtrace}"
+    rescue => e
+      if logger
+        logger.error "Could not log #{name.inspect} event. #{e.class}: #{e.message} #{e.backtrace}"
+      end
     end
 
-  protected
+  private
 
     %w(info debug warn error fatal unknown).each do |level|
       class_eval <<-METHOD, __FILE__, __LINE__ + 1
@@ -99,7 +102,7 @@ module ActiveSupport
     # option is set to +true+, it also adds bold to the string. This is based
     # on the Highline implementation and will automatically append CLEAR to the
     # end of the returned String.
-    def color(text, color, bold=false)
+    def color(text, color, bold = false) # :doc:
       return text unless colorize_logging
       color = self.class.const_get(color.upcase) if color.is_a?(Symbol)
       bold  = bold ? BOLD : ""
diff --git a/activesupport/lib/active_support/log_subscriber/test_helper.rb b/activesupport/lib/active_support/log_subscriber/test_helper.rb
index 588ed67c81..3f19ef5009 100644
--- a/activesupport/lib/active_support/log_subscriber/test_helper.rb
+++ b/activesupport/lib/active_support/log_subscriber/test_helper.rb
@@ -1,6 +1,8 @@
-require 'active_support/log_subscriber'
-require 'active_support/logger'
-require 'active_support/notifications'
+# frozen_string_literal: true
+
+require "active_support/log_subscriber"
+require "active_support/logger"
+require "active_support/notifications"
 
 module ActiveSupport
   class LogSubscriber
@@ -58,15 +60,15 @@ module ActiveSupport
         def initialize(level = DEBUG)
           @flush_count = 0
           @level = level
-          @logged = Hash.new { |h,k| h[k] = [] }
+          @logged = Hash.new { |h, k| h[k] = [] }
         end
 
         def method_missing(level, message = nil)
-           if block_given?
-             @logged[level] << yield
-           else
-             @logged[level] << message
-           end
+          if block_given?
+            @logged[level] << yield
+          else
+            @logged[level] << message
+          end
         end
 
         def logged(level)
diff --git a/activesupport/lib/active_support/logger.rb b/activesupport/lib/active_support/logger.rb
index 92b890dbb0..8152a182b4 100644
--- a/activesupport/lib/active_support/logger.rb
+++ b/activesupport/lib/active_support/logger.rb
@@ -1,6 +1,8 @@
-require 'active_support/logger_silence'
-require 'active_support/logger_thread_safe_level'
-require 'logger'
+# frozen_string_literal: true
+
+require "active_support/logger_silence"
+require "active_support/logger_thread_safe_level"
+require "logger"
 
 module ActiveSupport
   class Logger < ::Logger
@@ -59,14 +61,14 @@ module ActiveSupport
         define_method(:silence) do |level = Logger::ERROR, &block|
           if logger.respond_to?(:silence)
             logger.silence(level) do
-              if respond_to?(:silence)
+              if defined?(super)
                 super(level, &block)
               else
                 block.call(self)
               end
             end
           else
-            if respond_to?(:silence)
+            if defined?(super)
               super(level, &block)
             else
               block.call(self)
diff --git a/activesupport/lib/active_support/logger_silence.rb b/activesupport/lib/active_support/logger_silence.rb
index 3eb8098c77..89f32b6782 100644
--- a/activesupport/lib/active_support/logger_silence.rb
+++ b/activesupport/lib/active_support/logger_silence.rb
@@ -1,13 +1,14 @@
-require 'active_support/concern'
-require 'active_support/core_ext/module/attribute_accessors'
-require 'concurrent'
+# frozen_string_literal: true
+
+require "active_support/concern"
+require "active_support/core_ext/module/attribute_accessors"
+require "concurrent"
 
 module LoggerSilence
   extend ActiveSupport::Concern
 
   included do
-    cattr_accessor :silencer
-    self.silencer = true
+    cattr_accessor :silencer, default: true
   end
 
   # Silences the logger for the duration of the block.
diff --git a/activesupport/lib/active_support/logger_thread_safe_level.rb b/activesupport/lib/active_support/logger_thread_safe_level.rb
index 5fedb5e689..ba32813d3d 100644
--- a/activesupport/lib/active_support/logger_thread_safe_level.rb
+++ b/activesupport/lib/active_support/logger_thread_safe_level.rb
@@ -1,4 +1,6 @@
-require 'active_support/concern'
+# frozen_string_literal: true
+
+require "active_support/concern"
 
 module ActiveSupport
   module LoggerThreadSafeLevel # :nodoc:
diff --git a/activesupport/lib/active_support/message_encryptor.rb b/activesupport/lib/active_support/message_encryptor.rb
index 721efea789..27fd061947 100644
--- a/activesupport/lib/active_support/message_encryptor.rb
+++ b/activesupport/lib/active_support/message_encryptor.rb
@@ -1,6 +1,10 @@
-require 'openssl'
-require 'base64'
-require 'active_support/core_ext/array/extract_options'
+# frozen_string_literal: true
+
+require "openssl"
+require "base64"
+require "active_support/core_ext/array/extract_options"
+require "active_support/message_verifier"
+require "active_support/messages/metadata"
 
 module ActiveSupport
   # MessageEncryptor is a simple way to encrypt values which get stored
@@ -12,12 +16,83 @@ module ActiveSupport
   # This can be used in situations similar to the <tt>MessageVerifier</tt>, but
   # where you don't want users to be able to determine the value of the payload.
   #
-  #   salt  = SecureRandom.random_bytes(64)
-  #   key   = ActiveSupport::KeyGenerator.new('password').generate_key(salt) # => "\x89\xE0\x156\xAC..."
-  #   crypt = ActiveSupport::MessageEncryptor.new(key)                       # => #<ActiveSupport::MessageEncryptor ...>
-  #   encrypted_data = crypt.encrypt_and_sign('my secret data')              # => "NlFBTTMwOUV5UlA1QlNEN2xkY2d6eThYWWh..."
-  #   crypt.decrypt_and_verify(encrypted_data)                               # => "my secret data"
+  #   len   = ActiveSupport::MessageEncryptor.key_len
+  #   salt  = SecureRandom.random_bytes(len)
+  #   key   = ActiveSupport::KeyGenerator.new('password').generate_key(salt, len) # => "\x89\xE0\x156\xAC..."
+  #   crypt = ActiveSupport::MessageEncryptor.new(key)                            # => #<ActiveSupport::MessageEncryptor ...>
+  #   encrypted_data = crypt.encrypt_and_sign('my secret data')                   # => "NlFBTTMwOUV5UlA1QlNEN2xkY2d6eThYWWh..."
+  #   crypt.decrypt_and_verify(encrypted_data)                                    # => "my secret data"
+  #
+  # === Confining messages to a specific purpose
+  #
+  # By default any message can be used throughout your app. But they can also be
+  # confined to a specific +:purpose+.
+  #
+  #   token = crypt.encrypt_and_sign("this is the chair", purpose: :login)
+  #
+  # Then that same purpose must be passed when verifying to get the data back out:
+  #
+  #   crypt.decrypt_and_verify(token, purpose: :login)    # => "this is the chair"
+  #   crypt.decrypt_and_verify(token, purpose: :shipping) # => nil
+  #   crypt.decrypt_and_verify(token)                     # => nil
+  #
+  # Likewise, if a message has no purpose it won't be returned when verifying with
+  # a specific purpose.
+  #
+  #   token = crypt.encrypt_and_sign("the conversation is lively")
+  #   crypt.decrypt_and_verify(token, purpose: :scare_tactics) # => nil
+  #   crypt.decrypt_and_verify(token)                          # => "the conversation is lively"
+  #
+  # === Making messages expire
+  #
+  # By default messages last forever and verifying one year from now will still
+  # return the original value. But messages can be set to expire at a given
+  # time with +:expires_in+ or +:expires_at+.
+  #
+  #   crypt.encrypt_and_sign(parcel, expires_in: 1.month)
+  #   crypt.encrypt_and_sign(doowad, expires_at: Time.now.end_of_year)
+  #
+  # Then the messages can be verified and returned upto the expire time.
+  # Thereafter, verifying returns +nil+.
+  #
+  # === Rotating keys
+  #
+  # MessageEncryptor also supports rotating out old configurations by falling
+  # back to a stack of encryptors. Call +rotate+ to build and add an encryptor
+  # so +decrypt_and_verify+ will also try the fallback.
+  #
+  # By default any rotated encryptors use the values of the primary
+  # encryptor unless specified otherwise.
+  #
+  # You'd give your encryptor the new defaults:
+  #
+  #   crypt = ActiveSupport::MessageEncryptor.new(@secret, cipher: "aes-256-gcm")
+  #
+  # Then gradually rotate the old values out by adding them as fallbacks. Any message
+  # generated with the old values will then work until the rotation is removed.
+  #
+  #   crypt.rotate old_secret            # Fallback to an old secret instead of @secret.
+  #   crypt.rotate cipher: "aes-256-cbc" # Fallback to an old cipher instead of aes-256-gcm.
+  #
+  # Though if both the secret and the cipher was changed at the same time,
+  # the above should be combined into:
+  #
+  #   crypt.rotate old_secret, cipher: "aes-256-cbc"
   class MessageEncryptor
+    prepend Messages::Rotator::Encryptor
+
+    class << self
+      attr_accessor :use_authenticated_message_encryption #:nodoc:
+
+      def default_cipher #:nodoc:
+        if use_authenticated_message_encryption
+          "aes-256-gcm"
+        else
+          "aes-256-cbc"
+        end
+      end
+    end
+
     module NullSerializer #:nodoc:
       def self.load(value)
         value
@@ -28,80 +103,126 @@ module ActiveSupport
       end
     end
 
+    module NullVerifier #:nodoc:
+      def self.verify(value)
+        value
+      end
+
+      def self.generate(value)
+        value
+      end
+    end
+
     class InvalidMessage < StandardError; end
     OpenSSLCipherError = OpenSSL::Cipher::CipherError
 
     # Initialize a new MessageEncryptor. +secret+ must be at least as long as
-    # the cipher key size. For the default 'aes-256-cbc' cipher, this is 256
+    # the cipher key size. For the default 'aes-256-gcm' cipher, this is 256
     # bits. If you are using a user-entered secret, you can generate a suitable
     # key by using <tt>ActiveSupport::KeyGenerator</tt> or a similar key
     # derivation function.
     #
+    # First additional parameter is used as the signature key for +MessageVerifier+.
+    # This allows you to specify keys to encrypt and sign data.
+    #
+    #    ActiveSupport::MessageEncryptor.new('secret', 'signature_secret')
+    #
     # Options:
     # * <tt>:cipher</tt>     - Cipher to use. Can be any cipher returned by
-    #   <tt>OpenSSL::Cipher.ciphers</tt>. Default is 'aes-256-cbc'.
-    # * <tt>:digest</tt> - String of digest to use for signing. Default is +SHA1+.
+    #   <tt>OpenSSL::Cipher.ciphers</tt>. Default is 'aes-256-gcm'.
+    # * <tt>:digest</tt> - String of digest to use for signing. Default is
+    #   +SHA1+. Ignored when using an AEAD cipher like 'aes-256-gcm'.
     # * <tt>:serializer</tt> - Object serializer to use. Default is +Marshal+.
     def initialize(secret, *signature_key_or_options)
       options = signature_key_or_options.extract_options!
       sign_secret = signature_key_or_options.first
       @secret = secret
       @sign_secret = sign_secret
-      @cipher = options[:cipher] || 'aes-256-cbc'
-      @verifier = MessageVerifier.new(@sign_secret || @secret, digest: options[:digest] || 'SHA1', serializer: NullSerializer)
+      @cipher = options[:cipher] || self.class.default_cipher
+      @digest = options[:digest] || "SHA1" unless aead_mode?
+      @verifier = resolve_verifier
       @serializer = options[:serializer] || Marshal
     end
 
     # Encrypt and sign a message. We need to sign the message in order to avoid
-    # padding attacks. Reference: http://www.limited-entropy.com/padding-oracle-attacks.
-    def encrypt_and_sign(value)
-      verifier.generate(_encrypt(value))
+    # padding attacks. Reference: https://www.limited-entropy.com/padding-oracle-attacks/.
+    def encrypt_and_sign(value, expires_at: nil, expires_in: nil, purpose: nil)
+      verifier.generate(_encrypt(value, expires_at: expires_at, expires_in: expires_in, purpose: purpose))
     end
 
     # Decrypt and verify a message. We need to verify the message in order to
-    # avoid padding attacks. Reference: http://www.limited-entropy.com/padding-oracle-attacks.
-    def decrypt_and_verify(value)
-      _decrypt(verifier.verify(value))
+    # avoid padding attacks. Reference: https://www.limited-entropy.com/padding-oracle-attacks/.
+    def decrypt_and_verify(data, purpose: nil, **)
+      _decrypt(verifier.verify(data), purpose)
     end
 
-    private
-
-    def _encrypt(value)
-      cipher = new_cipher
-      cipher.encrypt
-      cipher.key = @secret
+    # Given a cipher, returns the key length of the cipher to help generate the key of desired size
+    def self.key_len(cipher = default_cipher)
+      OpenSSL::Cipher.new(cipher).key_len
+    end
 
-      # Rely on OpenSSL for the initialization vector
-      iv = cipher.random_iv
+    private
+      def _encrypt(value, **metadata_options)
+        cipher = new_cipher
+        cipher.encrypt
+        cipher.key = @secret
 
-      encrypted_data = cipher.update(@serializer.dump(value))
-      encrypted_data << cipher.final
+        # Rely on OpenSSL for the initialization vector
+        iv = cipher.random_iv
+        cipher.auth_data = "" if aead_mode?
 
-      "#{::Base64.strict_encode64 encrypted_data}--#{::Base64.strict_encode64 iv}"
-    end
+        encrypted_data = cipher.update(Messages::Metadata.wrap(@serializer.dump(value), metadata_options))
+        encrypted_data << cipher.final
 
-    def _decrypt(encrypted_message)
-      cipher = new_cipher
-      encrypted_data, iv = encrypted_message.split("--".freeze).map {|v| ::Base64.strict_decode64(v)}
+        blob = "#{::Base64.strict_encode64 encrypted_data}--#{::Base64.strict_encode64 iv}"
+        blob = "#{blob}--#{::Base64.strict_encode64 cipher.auth_tag}" if aead_mode?
+        blob
+      end
 
-      cipher.decrypt
-      cipher.key = @secret
-      cipher.iv  = iv
+      def _decrypt(encrypted_message, purpose)
+        cipher = new_cipher
+        encrypted_data, iv, auth_tag = encrypted_message.split("--".freeze).map { |v| ::Base64.strict_decode64(v) }
+
+        # Currently the OpenSSL bindings do not raise an error if auth_tag is
+        # truncated, which would allow an attacker to easily forge it. See
+        # https://github.com/ruby/openssl/issues/63
+        raise InvalidMessage if aead_mode? && (auth_tag.nil? || auth_tag.bytes.length != 16)
+
+        cipher.decrypt
+        cipher.key = @secret
+        cipher.iv  = iv
+        if aead_mode?
+          cipher.auth_tag = auth_tag
+          cipher.auth_data = ""
+        end
+
+        decrypted_data = cipher.update(encrypted_data)
+        decrypted_data << cipher.final
+
+        message = Messages::Metadata.verify(decrypted_data, purpose)
+        @serializer.load(message) if message
+      rescue OpenSSLCipherError, TypeError, ArgumentError
+        raise InvalidMessage
+      end
 
-      decrypted_data = cipher.update(encrypted_data)
-      decrypted_data << cipher.final
+      def new_cipher
+        OpenSSL::Cipher.new(@cipher)
+      end
 
-      @serializer.load(decrypted_data)
-    rescue OpenSSLCipherError, TypeError, ArgumentError
-      raise InvalidMessage
-    end
+      def verifier
+        @verifier
+      end
 
-    def new_cipher
-      OpenSSL::Cipher.new(@cipher)
-    end
+      def aead_mode?
+        @aead_mode ||= new_cipher.authenticated?
+      end
 
-    def verifier
-      @verifier
-    end
+      def resolve_verifier
+        if aead_mode?
+          NullVerifier
+        else
+          MessageVerifier.new(@sign_secret || @secret, digest: @digest, serializer: NullSerializer)
+        end
+      end
   end
 end
diff --git a/activesupport/lib/active_support/message_verifier.rb b/activesupport/lib/active_support/message_verifier.rb
index 4c3deffe6e..83c39c0a86 100644
--- a/activesupport/lib/active_support/message_verifier.rb
+++ b/activesupport/lib/active_support/message_verifier.rb
@@ -1,6 +1,10 @@
-require 'base64'
-require 'active_support/core_ext/object/blank'
-require 'active_support/security_utils'
+# frozen_string_literal: true
+
+require "base64"
+require "active_support/core_ext/object/blank"
+require "active_support/security_utils"
+require "active_support/messages/metadata"
+require "active_support/messages/rotator"
 
 module ActiveSupport
   # +MessageVerifier+ makes it easy to generate and verify messages which are
@@ -27,16 +31,82 @@ module ActiveSupport
   #
   # +MessageVerifier+ creates HMAC signatures using SHA1 hash algorithm by default.
   # If you want to use a different hash algorithm, you can change it by providing
-  # `:digest` key as an option while initializing the verifier:
+  # +:digest+ key as an option while initializing the verifier:
   #
   #   @verifier = ActiveSupport::MessageVerifier.new('s3Krit', digest: 'SHA256')
+  #
+  # === Confining messages to a specific purpose
+  #
+  # By default any message can be used throughout your app. But they can also be
+  # confined to a specific +:purpose+.
+  #
+  #   token = @verifier.generate("this is the chair", purpose: :login)
+  #
+  # Then that same purpose must be passed when verifying to get the data back out:
+  #
+  #   @verifier.verified(token, purpose: :login)    # => "this is the chair"
+  #   @verifier.verified(token, purpose: :shipping) # => nil
+  #   @verifier.verified(token)                     # => nil
+  #
+  #   @verifier.verify(token, purpose: :login)      # => "this is the chair"
+  #   @verifier.verify(token, purpose: :shipping)   # => ActiveSupport::MessageVerifier::InvalidSignature
+  #   @verifier.verify(token)                       # => ActiveSupport::MessageVerifier::InvalidSignature
+  #
+  # Likewise, if a message has no purpose it won't be returned when verifying with
+  # a specific purpose.
+  #
+  #   token = @verifier.generate("the conversation is lively")
+  #   @verifier.verified(token, purpose: :scare_tactics) # => nil
+  #   @verifier.verified(token)                          # => "the conversation is lively"
+  #
+  #   @verifier.verify(token, purpose: :scare_tactics)   # => ActiveSupport::MessageVerifier::InvalidSignature
+  #   @verifier.verify(token)                            # => "the conversation is lively"
+  #
+  # === Making messages expire
+  #
+  # By default messages last forever and verifying one year from now will still
+  # return the original value. But messages can be set to expire at a given
+  # time with +:expires_in+ or +:expires_at+.
+  #
+  #   @verifier.generate(parcel, expires_in: 1.month)
+  #   @verifier.generate(doowad, expires_at: Time.now.end_of_year)
+  #
+  # Then the messages can be verified and returned upto the expire time.
+  # Thereafter, the +verified+ method returns +nil+ while +verify+ raises
+  # <tt>ActiveSupport::MessageVerifier::InvalidSignature</tt>.
+  #
+  # === Rotating keys
+  #
+  # MessageVerifier also supports rotating out old configurations by falling
+  # back to a stack of verifiers. Call +rotate+ to build and add a verifier to
+  # so either +verified+ or +verify+ will also try verifying with the fallback.
+  #
+  # By default any rotated verifiers use the values of the primary
+  # verifier unless specified otherwise.
+  #
+  # You'd give your verifier the new defaults:
+  #
+  #   verifier = ActiveSupport::MessageVerifier.new(@secret, digest: "SHA512", serializer: JSON)
+  #
+  # Then gradually rotate the old values out by adding them as fallbacks. Any message
+  # generated with the old values will then work until the rotation is removed.
+  #
+  #   verifier.rotate old_secret          # Fallback to an old secret instead of @secret.
+  #   verifier.rotate digest: "SHA256"    # Fallback to an old digest instead of SHA512.
+  #   verifier.rotate serializer: Marshal # Fallback to an old serializer instead of JSON.
+  #
+  # Though the above would most likely be combined into one rotation:
+  #
+  #   verifier.rotate old_secret, digest: "SHA256", serializer: Marshal
   class MessageVerifier
+    prepend Messages::Rotator::Verifier
+
     class InvalidSignature < StandardError; end
 
     def initialize(secret, options = {})
-      raise ArgumentError, 'Secret should not be nil.' unless secret
+      raise ArgumentError, "Secret should not be nil." unless secret
       @secret = secret
-      @digest = options[:digest] || 'SHA1'
+      @digest = options[:digest] || "SHA1"
       @serializer = options[:serializer] || Marshal
     end
 
@@ -77,13 +147,14 @@ module ActiveSupport
     #
     #   incompatible_message = "test--dad7b06c94abba8d46a15fafaef56c327665d5ff"
     #   verifier.verified(incompatible_message) # => TypeError: incompatible marshal file format
-    def verified(signed_message)
+    def verified(signed_message, purpose: nil, **)
       if valid_message?(signed_message)
         begin
           data = signed_message.split("--".freeze)[0]
-          @serializer.load(decode(data))
+          message = Messages::Metadata.verify(decode(data), purpose)
+          @serializer.load(message) if message
         rescue ArgumentError => argument_error
-          return if argument_error.message =~ %r{invalid base64}
+          return if argument_error.message.include?("invalid base64")
           raise
         end
       end
@@ -101,8 +172,8 @@ module ActiveSupport
     #
     #   other_verifier = ActiveSupport::MessageVerifier.new 'd1ff3r3nt-s3Krit'
     #   other_verifier.verify(signed_message) # => ActiveSupport::MessageVerifier::InvalidSignature
-    def verify(signed_message)
-      verified(signed_message) || raise(InvalidSignature)
+    def verify(*args)
+      verified(*args) || raise(InvalidSignature)
     end
 
     # Generates a signed message for the provided value.
@@ -112,8 +183,8 @@ module ActiveSupport
     #
     #   verifier = ActiveSupport::MessageVerifier.new 's3Krit'
     #   verifier.generate 'a private message' # => "BAhJIhRwcml2YXRlLW1lc3NhZ2UGOgZFVA==--e2d724331ebdee96a10fb99b089508d1c72bd772"
-    def generate(value)
-      data = encode(@serializer.dump(value))
+    def generate(value, expires_at: nil, expires_in: nil, purpose: nil)
+      data = encode(Messages::Metadata.wrap(@serializer.dump(value), expires_at: expires_at, expires_in: expires_in, purpose: purpose))
       "#{data}--#{generate_digest(data)}"
     end
 
@@ -127,7 +198,7 @@ module ActiveSupport
       end
 
       def generate_digest(data)
-        require 'openssl' unless defined?(OpenSSL)
+        require "openssl" unless defined?(OpenSSL)
         OpenSSL::HMAC.hexdigest(OpenSSL::Digest.const_get(@digest).new, @secret, data)
       end
   end
diff --git a/activesupport/lib/active_support/messages/metadata.rb b/activesupport/lib/active_support/messages/metadata.rb
new file mode 100644
index 0000000000..e97caac766
--- /dev/null
+++ b/activesupport/lib/active_support/messages/metadata.rb
@@ -0,0 +1,71 @@
+# frozen_string_literal: true
+
+require "time"
+
+module ActiveSupport
+  module Messages #:nodoc:
+    class Metadata #:nodoc:
+      def initialize(message, expires_at = nil, purpose = nil)
+        @message, @expires_at, @purpose = message, expires_at, purpose
+      end
+
+      def as_json(options = {})
+        { _rails: { message: @message, exp: @expires_at, pur: @purpose } }
+      end
+
+      class << self
+        def wrap(message, expires_at: nil, expires_in: nil, purpose: nil)
+          if expires_at || expires_in || purpose
+            JSON.encode new(encode(message), pick_expiry(expires_at, expires_in), purpose)
+          else
+            message
+          end
+        end
+
+        def verify(message, purpose)
+          extract_metadata(message).verify(purpose)
+        end
+
+        private
+          def pick_expiry(expires_at, expires_in)
+            if expires_at
+              expires_at.utc.iso8601(3)
+            elsif expires_in
+              Time.now.utc.advance(seconds: expires_in).iso8601(3)
+            end
+          end
+
+          def extract_metadata(message)
+            data = JSON.decode(message) rescue nil
+
+            if data.is_a?(Hash) && data.key?("_rails")
+              new(decode(data["_rails"]["message"]), data["_rails"]["exp"], data["_rails"]["pur"])
+            else
+              new(message)
+            end
+          end
+
+          def encode(message)
+            ::Base64.strict_encode64(message)
+          end
+
+          def decode(message)
+            ::Base64.strict_decode64(message)
+          end
+      end
+
+      def verify(purpose)
+        @message if match?(purpose) && fresh?
+      end
+
+      private
+        def match?(purpose)
+          @purpose.to_s == purpose.to_s
+        end
+
+        def fresh?
+          @expires_at.nil? || Time.now.utc < Time.iso8601(@expires_at)
+        end
+    end
+  end
+end
diff --git a/activesupport/lib/active_support/messages/rotation_configuration.rb b/activesupport/lib/active_support/messages/rotation_configuration.rb
new file mode 100644
index 0000000000..bd50d6d348
--- /dev/null
+++ b/activesupport/lib/active_support/messages/rotation_configuration.rb
@@ -0,0 +1,22 @@
+# frozen_string_literal: true
+
+module ActiveSupport
+  module Messages
+    class RotationConfiguration # :nodoc:
+      attr_reader :signed, :encrypted
+
+      def initialize
+        @signed, @encrypted = [], []
+      end
+
+      def rotate(kind, *args)
+        case kind
+        when :signed
+          @signed << args
+        when :encrypted
+          @encrypted << args
+        end
+      end
+    end
+  end
+end
diff --git a/activesupport/lib/active_support/messages/rotator.rb b/activesupport/lib/active_support/messages/rotator.rb
new file mode 100644
index 0000000000..823a399d67
--- /dev/null
+++ b/activesupport/lib/active_support/messages/rotator.rb
@@ -0,0 +1,56 @@
+# frozen_string_literal: true
+
+module ActiveSupport
+  module Messages
+    module Rotator # :nodoc:
+      def initialize(*, **options)
+        super
+
+        @options   = options
+        @rotations = []
+      end
+
+      def rotate(*secrets, **options)
+        @rotations << build_rotation(*secrets, @options.merge(options))
+      end
+
+      module Encryptor
+        include Rotator
+
+        def decrypt_and_verify(*args, on_rotation: nil, **options)
+          super
+        rescue MessageEncryptor::InvalidMessage, MessageVerifier::InvalidSignature
+          run_rotations(on_rotation) { |encryptor| encryptor.decrypt_and_verify(*args, options) } || raise
+        end
+
+        private
+          def build_rotation(secret = @secret, sign_secret = @sign_secret, options)
+            self.class.new(secret, sign_secret, options)
+          end
+      end
+
+      module Verifier
+        include Rotator
+
+        def verified(*args, on_rotation: nil, **options)
+          super || run_rotations(on_rotation) { |verifier| verifier.verified(*args, options) }
+        end
+
+        private
+          def build_rotation(secret = @secret, options)
+            self.class.new(secret, options)
+          end
+      end
+
+      private
+        def run_rotations(on_rotation)
+          @rotations.find do |rotation|
+            if message = yield(rotation) rescue next
+              on_rotation.call if on_rotation
+              return message
+            end
+          end
+        end
+    end
+  end
+end
diff --git a/activesupport/lib/active_support/multibyte.rb b/activesupport/lib/active_support/multibyte.rb
index ffebd9a60b..3fe3a05e93 100644
--- a/activesupport/lib/active_support/multibyte.rb
+++ b/activesupport/lib/active_support/multibyte.rb
@@ -1,7 +1,9 @@
+# frozen_string_literal: true
+
 module ActiveSupport #:nodoc:
   module Multibyte
-    autoload :Chars, 'active_support/multibyte/chars'
-    autoload :Unicode, 'active_support/multibyte/unicode'
+    autoload :Chars, "active_support/multibyte/chars"
+    autoload :Unicode, "active_support/multibyte/unicode"
 
     # The proxy class returned when calling mb_chars. You can use this accessor
     # to configure your own proxy class so you can support other encodings. See
diff --git a/activesupport/lib/active_support/multibyte/chars.rb b/activesupport/lib/active_support/multibyte/chars.rb
index 707cf200b5..8152b8fd22 100644
--- a/activesupport/lib/active_support/multibyte/chars.rb
+++ b/activesupport/lib/active_support/multibyte/chars.rb
@@ -1,7 +1,10 @@
-require 'active_support/json'
-require 'active_support/core_ext/string/access'
-require 'active_support/core_ext/string/behavior'
-require 'active_support/core_ext/module/delegation'
+# frozen_string_literal: true
+
+require "active_support/json"
+require "active_support/core_ext/string/access"
+require "active_support/core_ext/string/behavior"
+require "active_support/core_ext/module/delegation"
+require "active_support/core_ext/regexp"
 
 module ActiveSupport #:nodoc:
   module Multibyte #:nodoc:
@@ -15,7 +18,8 @@ module ActiveSupport #:nodoc:
     # through the +mb_chars+ method. Methods which would normally return a
     # String object now return a Chars object so methods can be chained.
     #
-    #   'The Perfect String  '.mb_chars.downcase.strip.normalize # => "the perfect string"
+    #   'The Perfect String  '.mb_chars.downcase.strip.normalize
+    #   # => #<ActiveSupport::Multibyte::Chars:0x007fdc434ccc10 @wrapped_string="the perfect string">
     #
     # Chars objects are perfectly interchangeable with String objects as long as
     # no explicit class checks are made. If certain methods do explicitly check
@@ -45,7 +49,7 @@ module ActiveSupport #:nodoc:
       alias to_s wrapped_string
       alias to_str wrapped_string
 
-      delegate :<=>, :=~, :acts_like_string?, :to => :wrapped_string
+      delegate :<=>, :=~, :acts_like_string?, to: :wrapped_string
 
       # Creates a new Chars instance by wrapping _string_.
       def initialize(string)
@@ -56,7 +60,7 @@ module ActiveSupport #:nodoc:
       # Forward all undefined methods to the wrapped string.
       def method_missing(method, *args, &block)
         result = @wrapped_string.__send__(method, *args, &block)
-        if method.to_s =~ /!$/
+        if /!$/.match?(method)
           self if result
         else
           result.kind_of?(String) ? chars(result) : result
@@ -86,7 +90,7 @@ module ActiveSupport #:nodoc:
       end
 
       # Works like <tt>String#slice!</tt>, but returns an instance of
-      # Chars, or nil if the string was not modified. The string will not be
+      # Chars, or +nil+ if the string was not modified. The string will not be
       # modified if the range given is out of bounds
       #
       #   string = 'Welcome'
@@ -105,7 +109,7 @@ module ActiveSupport #:nodoc:
       #
       #   'Café'.mb_chars.reverse.to_s # => 'éfaC'
       def reverse
-        chars(Unicode.unpack_graphemes(@wrapped_string).reverse.flatten.pack('U*'))
+        chars(Unicode.unpack_graphemes(@wrapped_string).reverse.flatten.pack("U*"))
       end
 
       # Limits the byte size of the string to a number of bytes without breaking
@@ -133,7 +137,7 @@ module ActiveSupport #:nodoc:
 
       # Converts characters in the string to the opposite case.
       #
-      #    'El Cañón".mb_chars.swapcase.to_s # => "eL cAÑÓN"
+      #    'El Cañón'.mb_chars.swapcase.to_s # => "eL cAÑÓN"
       def swapcase
         chars Unicode.swapcase(@wrapped_string)
       end
@@ -142,15 +146,15 @@ module ActiveSupport #:nodoc:
       #
       #  'über'.mb_chars.capitalize.to_s # => "Über"
       def capitalize
-        (slice(0) || chars('')).upcase + (slice(1..-1) || chars('')).downcase
+        (slice(0) || chars("")).upcase + (slice(1..-1) || chars("")).downcase
       end
 
       # Capitalizes the first letter of every word, when possible.
       #
-      #   "ÉL QUE SE ENTERÓ".mb_chars.titleize    # => "Él Que Se Enteró"
-      #   "日本語".mb_chars.titleize                 # => "日本語"
+      #   "ÉL QUE SE ENTERÓ".mb_chars.titleize.to_s    # => "Él Que Se Enteró"
+      #   "日本語".mb_chars.titleize.to_s               # => "日本語"
       def titleize
-        chars(downcase.to_s.gsub(/\b('?\S)/u) { Unicode.upcase($1)})
+        chars(downcase.to_s.gsub(/\b('?\S)/u) { Unicode.upcase($1) })
       end
       alias_method :titlecase, :titleize
 
@@ -170,7 +174,7 @@ module ActiveSupport #:nodoc:
       #   'é'.length                         # => 2
       #   'é'.mb_chars.decompose.to_s.length # => 3
       def decompose
-        chars(Unicode.decompose(:canonical, @wrapped_string.codepoints.to_a).pack('U*'))
+        chars(Unicode.decompose(:canonical, @wrapped_string.codepoints.to_a).pack("U*"))
       end
 
       # Performs composition on all the characters.
@@ -178,7 +182,7 @@ module ActiveSupport #:nodoc:
       #   'é'.length                       # => 3
       #   'é'.mb_chars.compose.to_s.length # => 2
       def compose
-        chars(Unicode.compose(@wrapped_string.codepoints.to_a).pack('U*'))
+        chars(Unicode.compose(@wrapped_string.codepoints.to_a).pack("U*"))
       end
 
       # Returns the number of grapheme clusters in the string.
@@ -209,21 +213,21 @@ module ActiveSupport #:nodoc:
         end
       end
 
-      protected
+      private
 
-        def translate_offset(byte_offset) #:nodoc:
+        def translate_offset(byte_offset)
           return nil if byte_offset.nil?
-          return 0   if @wrapped_string == ''
+          return 0   if @wrapped_string == ""
 
           begin
-            @wrapped_string.byteslice(0...byte_offset).unpack('U*').length
+            @wrapped_string.byteslice(0...byte_offset).unpack("U*").length
           rescue ArgumentError
             byte_offset -= 1
             retry
           end
         end
 
-        def chars(string) #:nodoc:
+        def chars(string)
           self.class.new(string)
         end
     end
diff --git a/activesupport/lib/active_support/multibyte/unicode.rb b/activesupport/lib/active_support/multibyte/unicode.rb
index 72b20fff06..a64223c0e0 100644
--- a/activesupport/lib/active_support/multibyte/unicode.rb
+++ b/activesupport/lib/active_support/multibyte/unicode.rb
@@ -1,7 +1,8 @@
+# frozen_string_literal: true
+
 module ActiveSupport
   module Multibyte
     module Unicode
-
       extend self
 
       # A list of all available normalization forms.
@@ -10,7 +11,7 @@ module ActiveSupport
       NORMALIZATION_FORMS = [:c, :kc, :d, :kd]
 
       # The Unicode version that is supported by the implementation
-      UNICODE_VERSION = '8.0.0'
+      UNICODE_VERSION = "9.0.0"
 
       # The default normalization used for operations that require
       # normalization. It can be set to any of the normalizations
@@ -31,36 +32,6 @@ module ActiveSupport
       HANGUL_NCOUNT = HANGUL_VCOUNT * HANGUL_TCOUNT
       HANGUL_SCOUNT = 11172
       HANGUL_SLAST = HANGUL_SBASE + HANGUL_SCOUNT
-      HANGUL_JAMO_FIRST = 0x1100
-      HANGUL_JAMO_LAST = 0x11FF
-
-      # All the unicode whitespace
-      WHITESPACE = [
-        (0x0009..0x000D).to_a, # White_Space # Cc   [5] <control-0009>..<control-000D>
-        0x0020,                # White_Space # Zs       SPACE
-        0x0085,                # White_Space # Cc       <control-0085>
-        0x00A0,                # White_Space # Zs       NO-BREAK SPACE
-        0x1680,                # White_Space # Zs       OGHAM SPACE MARK
-        (0x2000..0x200A).to_a, # White_Space # Zs  [11] EN QUAD..HAIR SPACE
-        0x2028,                # White_Space # Zl       LINE SEPARATOR
-        0x2029,                # White_Space # Zp       PARAGRAPH SEPARATOR
-        0x202F,                # White_Space # Zs       NARROW NO-BREAK SPACE
-        0x205F,                # White_Space # Zs       MEDIUM MATHEMATICAL SPACE
-        0x3000,                # White_Space # Zs       IDEOGRAPHIC SPACE
-      ].flatten.freeze
-
-      # BOM (byte order mark) can also be seen as whitespace, it's a
-      # non-rendering character used to distinguish between little and big
-      # endian. This is not an issue in utf-8, so it must be ignored.
-      LEADERS_AND_TRAILERS = WHITESPACE + [65279] # ZERO-WIDTH NO-BREAK SPACE aka BOM
-
-      # Returns a regular expression pattern that matches the passed Unicode
-      # codepoints.
-      def self.codepoints_to_pattern(array_of_codepoints) #:nodoc:
-        array_of_codepoints.collect{ |e| [e].pack 'U*'.freeze }.join('|'.freeze)
-      end
-      TRAILERS_PAT = /(#{codepoints_to_pattern(LEADERS_AND_TRAILERS)})+\Z/u
-      LEADERS_PAT = /\A(#{codepoints_to_pattern(LEADERS_AND_TRAILERS)})+/u
 
       # Detect whether the codepoint is in a certain character class. Returns
       # +true+ when it's in the specified character class and +false+ otherwise.
@@ -83,35 +54,35 @@ module ActiveSupport
         pos = 0
         marker = 0
         eoc = codepoints.length
-        while(pos < eoc)
+        while (pos < eoc)
           pos += 1
-          previous = codepoints[pos-1]
+          previous = codepoints[pos - 1]
           current = codepoints[pos]
 
+          # See http://unicode.org/reports/tr29/#Grapheme_Cluster_Boundary_Rules
           should_break =
+            if pos == eoc
+              true
             # GB3. CR X LF
-            if previous == database.boundary[:cr] and current == database.boundary[:lf]
+            elsif previous == database.boundary[:cr] && current == database.boundary[:lf]
               false
             # GB4. (Control|CR|LF) ÷
-            elsif previous and in_char_class?(previous, [:control,:cr,:lf])
+            elsif previous && in_char_class?(previous, [:control, :cr, :lf])
               true
             # GB5. ÷ (Control|CR|LF)
-            elsif in_char_class?(current, [:control,:cr,:lf])
+            elsif in_char_class?(current, [:control, :cr, :lf])
               true
             # GB6. L X (L|V|LV|LVT)
-            elsif database.boundary[:l] === previous and in_char_class?(current, [:l,:v,:lv,:lvt])
+            elsif database.boundary[:l] === previous && in_char_class?(current, [:l, :v, :lv, :lvt])
               false
             # GB7. (LV|V) X (V|T)
-            elsif in_char_class?(previous, [:lv,:v]) and in_char_class?(current, [:v,:t])
+            elsif in_char_class?(previous, [:lv, :v]) && in_char_class?(current, [:v, :t])
               false
             # GB8. (LVT|T) X (T)
-            elsif in_char_class?(previous, [:lvt,:t]) and database.boundary[:t] === current
-              false
-            # GB8a. Regional_Indicator X Regional_Indicator
-            elsif database.boundary[:regional_indicator] === previous and database.boundary[:regional_indicator] === current
+            elsif in_char_class?(previous, [:lvt, :t]) && database.boundary[:t] === current
               false
-            # GB9. X Extend
-            elsif database.boundary[:extend] === current
+            # GB9. X (Extend | ZWJ)
+            elsif in_char_class?(current, [:extend, :zwj])
               false
             # GB9a. X SpacingMark
             elsif database.boundary[:spacingmark] === current
@@ -119,13 +90,23 @@ module ActiveSupport
             # GB9b. Prepend X
             elsif database.boundary[:prepend] === previous
               false
-            # GB10. Any ÷ Any
+            # GB10. (E_Base | EBG) Extend* X E_Modifier
+            elsif (marker...pos).any? { |i| in_char_class?(codepoints[i], [:e_base, :e_base_gaz]) && codepoints[i + 1...pos].all? { |c| database.boundary[:extend] === c } } && database.boundary[:e_modifier] === current
+              false
+            # GB11. ZWJ X (Glue_After_Zwj | EBG)
+            elsif database.boundary[:zwj] === previous && in_char_class?(current, [:glue_after_zwj, :e_base_gaz])
+              false
+            # GB12. ^ (RI RI)* RI X RI
+            # GB13. [^RI] (RI RI)* RI X RI
+            elsif codepoints[marker..pos].all? { |c| database.boundary[:regional_indicator] === c } && codepoints[marker..pos].count { |c| database.boundary[:regional_indicator] === c }.even?
+              false
+            # GB999. Any ÷ Any
             else
               true
             end
 
           if should_break
-            unpacked << codepoints[marker..pos-1]
+            unpacked << codepoints[marker..pos - 1]
             marker = pos
           end
         end
@@ -136,17 +117,17 @@ module ActiveSupport
       #
       #   Unicode.pack_graphemes(Unicode.unpack_graphemes('क्षि')) # => 'क्षि'
       def pack_graphemes(unpacked)
-        unpacked.flatten.pack('U*')
+        unpacked.flatten.pack("U*")
       end
 
       # Re-order codepoints so the string becomes canonical.
       def reorder_characters(codepoints)
-        length = codepoints.length- 1
+        length = codepoints.length - 1
         pos = 0
         while pos < length do
-          cp1, cp2 = database.codepoints[codepoints[pos]], database.codepoints[codepoints[pos+1]]
+          cp1, cp2 = database.codepoints[codepoints[pos]], database.codepoints[codepoints[pos + 1]]
           if (cp1.combining_class > cp2.combining_class) && (cp2.combining_class > 0)
-            codepoints[pos..pos+1] = cp2.code, cp1.code
+            codepoints[pos..pos + 1] = cp2.code, cp1.code
             pos += (pos > 0 ? -1 : 1)
           else
             pos += 1
@@ -159,7 +140,7 @@ module ActiveSupport
       def decompose(type, codepoints)
         codepoints.inject([]) do |decomposed, cp|
           # if it's a hangul syllable starter character
-          if HANGUL_SBASE <= cp and cp < HANGUL_SLAST
+          if HANGUL_SBASE <= cp && cp < HANGUL_SLAST
             sindex = cp - HANGUL_SBASE
             ncp = [] # new codepoints
             ncp << HANGUL_LBASE + sindex / HANGUL_NCOUNT
@@ -168,7 +149,7 @@ module ActiveSupport
             ncp << (HANGUL_TBASE + tindex) unless tindex == 0
             decomposed.concat ncp
           # if the codepoint is decomposable in with the current decomposition type
-          elsif (ncp = database.codepoints[cp].decomp_mapping) and (!database.codepoints[cp].decomp_type || type == :compatibility)
+          elsif (ncp = database.codepoints[cp].decomp_mapping) && (!database.codepoints[cp].decomp_type || type == :compatibility)
             decomposed.concat decompose(type, ncp.dup)
           else
             decomposed << cp
@@ -187,11 +168,11 @@ module ActiveSupport
           pos += 1
           lindex = starter_char - HANGUL_LBASE
           # -- Hangul
-          if 0 <= lindex and lindex < HANGUL_LCOUNT
-            vindex = codepoints[starter_pos+1] - HANGUL_VBASE rescue vindex = -1
-            if 0 <= vindex and vindex < HANGUL_VCOUNT
-              tindex = codepoints[starter_pos+2] - HANGUL_TBASE rescue tindex = -1
-              if 0 <= tindex and tindex < HANGUL_TCOUNT
+          if 0 <= lindex && lindex < HANGUL_LCOUNT
+            vindex = codepoints[starter_pos + 1] - HANGUL_VBASE rescue vindex = -1
+            if 0 <= vindex && vindex < HANGUL_VCOUNT
+              tindex = codepoints[starter_pos + 2] - HANGUL_TBASE rescue tindex = -1
+              if 0 <= tindex && tindex < HANGUL_TCOUNT
                 j = starter_pos + 2
                 eoa -= 2
               else
@@ -259,7 +240,7 @@ module ActiveSupport
           reader = Encoding::Converter.new(Encoding::UTF_8, Encoding::UTF_16LE)
 
           source = string.dup
-          out = ''.force_encoding(Encoding::UTF_16LE)
+          out = "".force_encoding(Encoding::UTF_16LE)
 
           loop do
             reader.primitive_convert(source, out)
@@ -282,22 +263,22 @@ module ActiveSupport
       # * <tt>form</tt> - The form you want to normalize in. Should be one of
       #   the following: <tt>:c</tt>, <tt>:kc</tt>, <tt>:d</tt>, or <tt>:kd</tt>.
       #   Default is ActiveSupport::Multibyte::Unicode.default_normalization_form.
-      def normalize(string, form=nil)
+      def normalize(string, form = nil)
         form ||= @default_normalization_form
         # See http://www.unicode.org/reports/tr15, Table 1
         codepoints = string.codepoints.to_a
         case form
-          when :d
-            reorder_characters(decompose(:canonical, codepoints))
-          when :c
-            compose(reorder_characters(decompose(:canonical, codepoints)))
-          when :kd
-            reorder_characters(decompose(:compatibility, codepoints))
-          when :kc
-            compose(reorder_characters(decompose(:compatibility, codepoints)))
+        when :d
+          reorder_characters(decompose(:canonical, codepoints))
+        when :c
+          compose(reorder_characters(decompose(:canonical, codepoints)))
+        when :kd
+          reorder_characters(decompose(:compatibility, codepoints))
+        when :kc
+          compose(reorder_characters(decompose(:compatibility, codepoints)))
           else
-            raise ArgumentError, "#{form} is not a valid normalization variant", caller
-        end.pack('U*'.freeze)
+          raise ArgumentError, "#{form} is not a valid normalization variant", caller
+        end.pack("U*".freeze)
       end
 
       def downcase(string)
@@ -356,7 +337,7 @@ module ActiveSupport
         # UnicodeDatabase.
         def load
           begin
-            @codepoints, @composition_exclusion, @composition_map, @boundary, @cp1252 = File.open(self.class.filename, 'rb') { |f| Marshal.load f.read }
+            @codepoints, @composition_exclusion, @composition_map, @boundary, @cp1252 = File.open(self.class.filename, "rb") { |f| Marshal.load f.read }
           rescue => e
             raise IOError.new("Couldn't load the Unicode tables for UTF8Handler (#{e.message}), ActiveSupport::Multibyte is unusable")
           end
@@ -378,7 +359,7 @@ module ActiveSupport
 
         # Returns the directory in which the data files are stored.
         def self.dirname
-          File.dirname(__FILE__) + '/../values/'
+          File.expand_path("../values", __dir__)
         end
 
         # Returns the filename for the data file for this version.
@@ -389,25 +370,25 @@ module ActiveSupport
 
       private
 
-      def apply_mapping(string, mapping) #:nodoc:
-        database.codepoints
-        string.each_codepoint.map do |codepoint|
-          cp = database.codepoints[codepoint]
-          if cp and (ncp = cp.send(mapping)) and ncp > 0
-            ncp
-          else
-            codepoint
-          end
-        end.pack('U*')
-      end
+        def apply_mapping(string, mapping)
+          database.codepoints
+          string.each_codepoint.map do |codepoint|
+            cp = database.codepoints[codepoint]
+            if cp && (ncp = cp.send(mapping)) && ncp > 0
+              ncp
+            else
+              codepoint
+            end
+          end.pack("U*")
+        end
 
-      def recode_windows1252_chars(string)
-        string.encode(Encoding::UTF_8, Encoding::Windows_1252, invalid: :replace, undef: :replace)
-      end
+        def recode_windows1252_chars(string)
+          string.encode(Encoding::UTF_8, Encoding::Windows_1252, invalid: :replace, undef: :replace)
+        end
 
-      def database
-        @database ||= UnicodeDatabase.new
-      end
+        def database
+          @database ||= UnicodeDatabase.new
+        end
     end
   end
 end
diff --git a/activesupport/lib/active_support/notifications.rb b/activesupport/lib/active_support/notifications.rb
index 823d68e507..6207de8094 100644
--- a/activesupport/lib/active_support/notifications.rb
+++ b/activesupport/lib/active_support/notifications.rb
@@ -1,6 +1,8 @@
-require 'active_support/notifications/instrumenter'
-require 'active_support/notifications/fanout'
-require 'active_support/per_thread_registry'
+# frozen_string_literal: true
+
+require "active_support/notifications/instrumenter"
+require "active_support/notifications/fanout"
+require "active_support/per_thread_registry"
 
 module ActiveSupport
   # = Notifications
@@ -13,7 +15,7 @@ module ActiveSupport
   # To instrument an event you just need to do:
   #
   #   ActiveSupport::Notifications.instrument('render', extra: :information) do
-  #     render text: 'Foo'
+  #     render plain: 'Foo'
   #   end
   #
   # That first executes the block and then notifies all subscribers once done.
@@ -48,7 +50,7 @@ module ActiveSupport
   # The block is saved and will be called whenever someone instruments "render":
   #
   #   ActiveSupport::Notifications.instrument('render', extra: :information) do
-  #     render text: 'Foo'
+  #     render plain: 'Foo'
   #   end
   #
   #   event = events.first
@@ -64,6 +66,8 @@ module ActiveSupport
   # If an exception happens during that particular instrumentation the payload will
   # have a key <tt>:exception</tt> with an array of two elements as value: a string with
   # the name of the exception class, and the exception message.
+  # The <tt>:exception_object</tt> key of the payload will have the exception
+  # itself as the value.
   #
   # As the previous example depicts, the class <tt>ActiveSupport::Notifications::Event</tt>
   # is able to take the arguments as they come and provide an object-oriented
diff --git a/activesupport/lib/active_support/notifications/fanout.rb b/activesupport/lib/active_support/notifications/fanout.rb
index c53f9c1039..25aab175b4 100644
--- a/activesupport/lib/active_support/notifications/fanout.rb
+++ b/activesupport/lib/active_support/notifications/fanout.rb
@@ -1,5 +1,7 @@
-require 'mutex_m'
-require 'concurrent/map'
+# frozen_string_literal: true
+
+require "mutex_m"
+require "concurrent/map"
 
 module ActiveSupport
   module Notifications
@@ -68,7 +70,7 @@ module ActiveSupport
 
       module Subscribers # :nodoc:
         def self.new(pattern, listener)
-          if listener.respond_to?(:start) and listener.respond_to?(:finish)
+          if listener.respond_to?(:start) && listener.respond_to?(:finish)
             subscriber = Evented.new pattern, listener
           else
             subscriber = Timed.new pattern, listener
diff --git a/activesupport/lib/active_support/notifications/instrumenter.rb b/activesupport/lib/active_support/notifications/instrumenter.rb
index 91f94cb2d7..e99f5ee688 100644
--- a/activesupport/lib/active_support/notifications/instrumenter.rb
+++ b/activesupport/lib/active_support/notifications/instrumenter.rb
@@ -1,4 +1,6 @@
-require 'securerandom'
+# frozen_string_literal: true
+
+require "securerandom"
 
 module ActiveSupport
   module Notifications
@@ -14,7 +16,7 @@ module ActiveSupport
       # Instrument the given block by measuring the time taken to execute it
       # and publish it. Notice that events get sent even if an error occurs
       # in the passed-in block.
-      def instrument(name, payload={})
+      def instrument(name, payload = {})
         # some of the listeners might have state
         listeners_state = start name, payload
         begin
@@ -44,9 +46,9 @@ module ActiveSupport
 
       private
 
-      def unique_id
-        SecureRandom.hex(10)
-      end
+        def unique_id
+          SecureRandom.hex(10)
+        end
     end
 
     class Event
diff --git a/activesupport/lib/active_support/number_helper.rb b/activesupport/lib/active_support/number_helper.rb
index 7a49bbb960..8fd6e932f1 100644
--- a/activesupport/lib/active_support/number_helper.rb
+++ b/activesupport/lib/active_support/number_helper.rb
@@ -1,9 +1,12 @@
+# frozen_string_literal: true
+
 module ActiveSupport
   module NumberHelper
     extend ActiveSupport::Autoload
 
     eager_autoload do
       autoload :NumberConverter
+      autoload :RoundingHelper
       autoload :NumberToRoundedConverter
       autoload :NumberToDelimitedConverter
       autoload :NumberToHumanConverter
@@ -45,7 +48,7 @@ module ActiveSupport
     #
     #   number_to_phone(75561234567, pattern: /(\d{1,4})(\d{4})(\d{4})$/, area_code: true)
     #   # => "(755) 6123-4567"
-    #   number_to_phone(13312345678, pattern: /(\d{3})(\d{4})(\d{4})$/))
+    #   number_to_phone(13312345678, pattern: /(\d{3})(\d{4})(\d{4})$/)
     #   # => "133-1234-5678"
     def number_to_phone(number, options = {})
       NumberToPhoneConverter.convert(number, options)
@@ -78,7 +81,7 @@ module ActiveSupport
     #   (defaults to "%u%n").  Fields are <tt>%u</tt> for the
     #   currency, and <tt>%n</tt> for the number.
     # * <tt>:negative_format</tt> - Sets the format for negative
-    #   numbers (defaults to prepending an hyphen to the formatted
+    #   numbers (defaults to prepending a hyphen to the formatted
     #   number given by <tt>:format</tt>).  Accepts the same fields
     #   than <tt>:format</tt>, except <tt>%n</tt> is here the
     #   absolute value of the number.
@@ -109,7 +112,7 @@ module ActiveSupport
     # * <tt>:locale</tt> - Sets the locale to be used for formatting
     #   (defaults to current locale).
     # * <tt>:precision</tt> - Sets the precision of the number
-    #   (defaults to 3). Keeps the number's precision if nil.
+    #   (defaults to 3). Keeps the number's precision if +nil+.
     # * <tt>:significant</tt> - If +true+, precision will be the number
     #   of significant_digits. If +false+, the number of fractional
     #   digits (defaults to +false+).
@@ -183,7 +186,7 @@ module ActiveSupport
     # * <tt>:locale</tt> - Sets the locale to be used for formatting
     #   (defaults to current locale).
     # * <tt>:precision</tt> - Sets the precision of the number
-    #   (defaults to 3). Keeps the number's precision if nil.
+    #   (defaults to 3). Keeps the number's precision if +nil+.
     # * <tt>:significant</tt> - If +true+, precision will be the number
     #   of significant_digits. If +false+, the number of fractional
     #   digits (defaults to +false+).
diff --git a/activesupport/lib/active_support/number_helper/number_converter.rb b/activesupport/lib/active_support/number_helper/number_converter.rb
index 9d976f1831..06ba797a13 100644
--- a/activesupport/lib/active_support/number_helper/number_converter.rb
+++ b/activesupport/lib/active_support/number_helper/number_converter.rb
@@ -1,8 +1,10 @@
-require 'active_support/core_ext/big_decimal/conversions'
-require 'active_support/core_ext/object/blank'
-require 'active_support/core_ext/hash/keys'
-require 'active_support/i18n'
-require 'active_support/core_ext/class/attribute'
+# frozen_string_literal: true
+
+require "active_support/core_ext/big_decimal/conversions"
+require "active_support/core_ext/object/blank"
+require "active_support/core_ext/hash/keys"
+require "active_support/i18n"
+require "active_support/core_ext/class/attribute"
 
 module ActiveSupport
   module NumberHelper
@@ -139,17 +141,17 @@ module ActiveSupport
           @options ||= format_options.merge(opts)
         end
 
-        def format_options #:nodoc:
+        def format_options
           default_format_options.merge!(i18n_format_options)
         end
 
-        def default_format_options #:nodoc:
+        def default_format_options
           options = DEFAULTS[:format].dup
           options.merge!(DEFAULTS[namespace][:format]) if namespace
           options
         end
 
-        def i18n_format_options #:nodoc:
+        def i18n_format_options
           locale = opts[:locale]
           options = I18n.translate(:'number.format', locale: locale, default: {}).dup
 
@@ -160,7 +162,7 @@ module ActiveSupport
           options
         end
 
-        def translate_number_value_with_default(key, i18n_options = {}) #:nodoc:
+        def translate_number_value_with_default(key, i18n_options = {})
           I18n.translate(key, { default: default_value(key), scope: :number }.merge!(i18n_options))
         end
 
@@ -169,10 +171,10 @@ module ActiveSupport
         end
 
         def default_value(key)
-          key.split('.').reduce(DEFAULTS) { |defaults, k| defaults[k.to_sym] }
+          key.split(".").reduce(DEFAULTS) { |defaults, k| defaults[k.to_sym] }
         end
 
-        def valid_float? #:nodoc:
+        def valid_float?
           Float(number)
         rescue ArgumentError, TypeError
           false
diff --git a/activesupport/lib/active_support/number_helper/number_to_currency_converter.rb b/activesupport/lib/active_support/number_helper/number_to_currency_converter.rb
index 57f40f33bf..3f037c73ed 100644
--- a/activesupport/lib/active_support/number_helper/number_to_currency_converter.rb
+++ b/activesupport/lib/active_support/number_helper/number_to_currency_converter.rb
@@ -1,4 +1,6 @@
-require 'active_support/core_ext/numeric/inquiry'
+# frozen_string_literal: true
+
+require "active_support/core_ext/numeric/inquiry"
 
 module ActiveSupport
   module NumberHelper
@@ -15,13 +17,13 @@ module ActiveSupport
         end
 
         rounded_number = NumberToRoundedConverter.convert(number, options)
-        format.gsub('%n'.freeze, rounded_number).gsub('%u'.freeze, options[:unit])
+        format.gsub("%n".freeze, rounded_number).gsub("%u".freeze, options[:unit])
       end
 
       private
 
         def absolute_value(number)
-          number.respond_to?(:abs) ? number.abs : number.sub(/\A-/, '')
+          number.respond_to?(:abs) ? number.abs : number.sub(/\A-/, "")
         end
 
         def options
diff --git a/activesupport/lib/active_support/number_helper/number_to_delimited_converter.rb b/activesupport/lib/active_support/number_helper/number_to_delimited_converter.rb
index 43c5540b6f..d5b5706705 100644
--- a/activesupport/lib/active_support/number_helper/number_to_delimited_converter.rb
+++ b/activesupport/lib/active_support/number_helper/number_to_delimited_converter.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActiveSupport
   module NumberHelper
     class NumberToDelimitedConverter < NumberConverter #:nodoc:
@@ -12,7 +14,7 @@ module ActiveSupport
       private
 
         def parts
-          left, right = number.to_s.split('.'.freeze)
+          left, right = number.to_s.split(".".freeze)
           left.gsub!(delimiter_pattern) do |digit_to_delimit|
             "#{digit_to_delimit}#{options[:delimiter]}"
           end
@@ -22,7 +24,6 @@ module ActiveSupport
         def delimiter_pattern
           options.fetch(:delimiter_pattern, DEFAULT_DELIMITER_REGEX)
         end
-
     end
   end
 end
diff --git a/activesupport/lib/active_support/number_helper/number_to_human_converter.rb b/activesupport/lib/active_support/number_helper/number_to_human_converter.rb
index 7a1f8171c0..03eb6671ec 100644
--- a/activesupport/lib/active_support/number_helper/number_to_human_converter.rb
+++ b/activesupport/lib/active_support/number_helper/number_to_human_converter.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActiveSupport
   module NumberHelper
     class NumberToHumanConverter < NumberConverter # :nodoc:
@@ -9,6 +11,7 @@ module ActiveSupport
       self.validate_float = true
 
       def convert # :nodoc:
+        @number = RoundingHelper.new(options).round(number)
         @number = Float(number)
 
         # for backwards compatibility with those that didn't add strip_insignificant_zeros to their locale files
@@ -18,29 +21,26 @@ module ActiveSupport
 
         units = opts[:units]
         exponent = calculate_exponent(units)
-        @number = number / (10 ** exponent)
+        @number = number / (10**exponent)
 
-        until (rounded_number = NumberToRoundedConverter.convert(number, options)) != NumberToRoundedConverter.convert(1000, options)
-          @number = number / 1000.0
-          exponent += 3
-        end
+        rounded_number = NumberToRoundedConverter.convert(number, options)
         unit = determine_unit(units, exponent)
-        format.gsub('%n'.freeze, rounded_number).gsub('%u'.freeze, unit).strip
+        format.gsub("%n".freeze, rounded_number).gsub("%u".freeze, unit).strip
       end
 
       private
 
         def format
-          options[:format] || translate_in_locale('human.decimal_units.format')
+          options[:format] || translate_in_locale("human.decimal_units.format")
         end
 
         def determine_unit(units, exponent)
           exp = DECIMAL_UNITS[exponent]
           case units
           when Hash
-            units[exp] || ''
+            units[exp] || ""
           when String, Symbol
-            I18n.translate("#{units}.#{exp}", :locale => options[:locale], :count => number.to_i)
+            I18n.translate("#{units}.#{exp}", locale: options[:locale], count: number.to_i)
           else
             translate_in_locale("human.decimal_units.units.#{exp}", count: number.to_i)
           end
@@ -56,7 +56,7 @@ module ActiveSupport
           when Hash
             units
           when String, Symbol
-            I18n.translate(units.to_s, :locale => options[:locale], :raise => true)
+            I18n.translate(units.to_s, locale: options[:locale], raise: true)
           when nil
             translate_in_locale("human.decimal_units.units", raise: true)
           else
diff --git a/activesupport/lib/active_support/number_helper/number_to_human_size_converter.rb b/activesupport/lib/active_support/number_helper/number_to_human_size_converter.rb
index a83b368b7f..842f2fc8df 100644
--- a/activesupport/lib/active_support/number_helper/number_to_human_size_converter.rb
+++ b/activesupport/lib/active_support/number_helper/number_to_human_size_converter.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActiveSupport
   module NumberHelper
     class NumberToHumanSizeConverter < NumberConverter #:nodoc:
@@ -7,10 +9,6 @@ module ActiveSupport
       self.validate_float = true
 
       def convert
-        if opts.key?(:prefix)
-          ActiveSupport::Deprecation.warn('The :prefix option of `number_to_human_size` is deprecated and will be removed in Rails 5.1 with no replacement.')
-        end
-
         @number = Float(number)
 
         # for backwards compatibility with those that didn't add strip_insignificant_zeros to their locale files
@@ -21,24 +19,24 @@ module ActiveSupport
         if smaller_than_base?
           number_to_format = number.to_i.to_s
         else
-          human_size = number / (base ** exponent)
+          human_size = number / (base**exponent)
           number_to_format = NumberToRoundedConverter.convert(human_size, options)
         end
-        conversion_format.gsub('%n'.freeze, number_to_format).gsub('%u'.freeze, unit)
+        conversion_format.gsub("%n".freeze, number_to_format).gsub("%u".freeze, unit)
       end
 
       private
 
         def conversion_format
-          translate_number_value_with_default('human.storage_units.format', :locale => options[:locale], :raise => true)
+          translate_number_value_with_default("human.storage_units.format", locale: options[:locale], raise: true)
         end
 
         def unit
-          translate_number_value_with_default(storage_unit_key, :locale => options[:locale], :count => number.to_i, :raise => true)
+          translate_number_value_with_default(storage_unit_key, locale: options[:locale], count: number.to_i, raise: true)
         end
 
         def storage_unit_key
-          key_end = smaller_than_base? ? 'byte' : STORAGE_UNITS[exponent]
+          key_end = smaller_than_base? ? "byte" : STORAGE_UNITS[exponent]
           "human.storage_units.units.#{key_end}"
         end
 
@@ -54,9 +52,8 @@ module ActiveSupport
         end
 
         def base
-          opts[:prefix] == :si ? 1000 : 1024
+          1024
         end
     end
   end
 end
-
diff --git a/activesupport/lib/active_support/number_helper/number_to_percentage_converter.rb b/activesupport/lib/active_support/number_helper/number_to_percentage_converter.rb
index 4c04d40c19..4dcdad2e2c 100644
--- a/activesupport/lib/active_support/number_helper/number_to_percentage_converter.rb
+++ b/activesupport/lib/active_support/number_helper/number_to_percentage_converter.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActiveSupport
   module NumberHelper
     class NumberToPercentageConverter < NumberConverter # :nodoc:
@@ -5,7 +7,7 @@ module ActiveSupport
 
       def convert
         rounded_number = NumberToRoundedConverter.convert(number, options)
-        options[:format].gsub('%n'.freeze, rounded_number)
+        options[:format].gsub("%n".freeze, rounded_number)
       end
     end
   end
diff --git a/activesupport/lib/active_support/number_helper/number_to_phone_converter.rb b/activesupport/lib/active_support/number_helper/number_to_phone_converter.rb
index dee74fa7a6..96410f4995 100644
--- a/activesupport/lib/active_support/number_helper/number_to_phone_converter.rb
+++ b/activesupport/lib/active_support/number_helper/number_to_phone_converter.rb
@@ -1,8 +1,10 @@
+# frozen_string_literal: true
+
 module ActiveSupport
   module NumberHelper
     class NumberToPhoneConverter < NumberConverter #:nodoc:
       def convert
-        str  = country_code(opts[:country_code])
+        str = country_code(opts[:country_code]).dup
         str << convert_to_phone_number(number.to_s.strip)
         str << phone_ext(opts[:extension])
       end
@@ -51,8 +53,6 @@ module ActiveSupport
         def regexp_pattern(default_pattern)
           opts.fetch :pattern, default_pattern
         end
-
     end
   end
 end
-
diff --git a/activesupport/lib/active_support/number_helper/number_to_rounded_converter.rb b/activesupport/lib/active_support/number_helper/number_to_rounded_converter.rb
index 9fb7dfb779..eb528a0583 100644
--- a/activesupport/lib/active_support/number_helper/number_to_rounded_converter.rb
+++ b/activesupport/lib/active_support/number_helper/number_to_rounded_converter.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActiveSupport
   module NumberHelper
     class NumberToRoundedConverter < NumberConverter # :nodoc:
@@ -5,40 +7,28 @@ module ActiveSupport
       self.validate_float = true
 
       def convert
-        precision = options.delete :precision
+        helper = RoundingHelper.new(options)
+        rounded_number = helper.round(number)
 
-        if precision
-          case number
-          when Float, String
-            @number = BigDecimal(number.to_s)
-          when Rational
-            @number = BigDecimal(number, digit_count(number.to_i) + precision)
-          else
-            @number = number.to_d
-          end
-
-          if options.delete(:significant) && precision > 0
-            digits, rounded_number = digits_and_rounded_number(precision)
+        if precision = options[:precision]
+          if options[:significant] && precision > 0
+            digits = helper.digit_count(rounded_number)
             precision -= digits
             precision = 0 if precision < 0 # don't let it be negative
-          else
-            rounded_number = number.round(precision)
-            rounded_number = rounded_number.to_i if precision == 0 && rounded_number.finite?
-            rounded_number = rounded_number.abs if rounded_number.zero? # prevent showing negative zeros
           end
 
           formatted_string =
             if BigDecimal === rounded_number && rounded_number.finite?
-              s = rounded_number.to_s('F')
-              s << '0'.freeze * precision
-              a, b = s.split('.'.freeze, 2)
-              a << '.'.freeze
+              s = rounded_number.to_s("F")
+              s << "0".freeze * precision
+              a, b = s.split(".".freeze, 2)
+              a << ".".freeze
               a << b[0, precision]
             else
               "%00.#{precision}f" % rounded_number
             end
         else
-          formatted_string = number
+          formatted_string = rounded_number
         end
 
         delimited_number = NumberToDelimitedConverter.convert(formatted_string, options)
@@ -47,26 +37,6 @@ module ActiveSupport
 
       private
 
-        def digits_and_rounded_number(precision)
-          if zero?
-            [1, 0]
-          else
-            digits = digit_count(number)
-            multiplier = 10 ** (digits - precision)
-            rounded_number = calculate_rounded_number(multiplier)
-            digits = digit_count(rounded_number) # After rounding, the number of digits may have changed
-            [digits, rounded_number]
-          end
-        end
-
-        def calculate_rounded_number(multiplier)
-          (number / BigDecimal.new(multiplier.to_f.to_s)).round * multiplier
-        end
-
-        def digit_count(number)
-          number.zero? ? 1 : (Math.log10(absolute_number(number)) + 1).floor
-        end
-
         def strip_insignificant_zeros
           options[:strip_insignificant_zeros]
         end
@@ -74,19 +44,11 @@ module ActiveSupport
         def format_number(number)
           if strip_insignificant_zeros
             escaped_separator = Regexp.escape(options[:separator])
-            number.sub(/(#{escaped_separator})(\d*[1-9])?0+\z/, '\1\2').sub(/#{escaped_separator}\z/, '')
+            number.sub(/(#{escaped_separator})(\d*[1-9])?0+\z/, '\1\2').sub(/#{escaped_separator}\z/, "")
           else
             number
           end
         end
-
-        def absolute_number(number)
-          number.respond_to?(:abs) ? number.abs : number.to_d.abs
-        end
-
-        def zero?
-          number.respond_to?(:zero?) ? number.zero? : number.to_d.zero?
-        end
     end
   end
 end
diff --git a/activesupport/lib/active_support/number_helper/rounding_helper.rb b/activesupport/lib/active_support/number_helper/rounding_helper.rb
new file mode 100644
index 0000000000..2ad8d49c4e
--- /dev/null
+++ b/activesupport/lib/active_support/number_helper/rounding_helper.rb
@@ -0,0 +1,66 @@
+# frozen_string_literal: true
+
+module ActiveSupport
+  module NumberHelper
+    class RoundingHelper # :nodoc:
+      attr_reader :options
+
+      def initialize(options)
+        @options = options
+      end
+
+      def round(number)
+        return number unless precision
+        number = convert_to_decimal(number)
+        if significant && precision > 0
+          round_significant(number)
+        else
+          round_without_significant(number)
+        end
+      end
+
+      def digit_count(number)
+        return 1 if number.zero?
+        (Math.log10(absolute_number(number)) + 1).floor
+      end
+
+      private
+        def round_without_significant(number)
+          number = number.round(precision)
+          number = number.to_i if precision == 0 && number.finite?
+          number = number.abs if number.zero? # prevent showing negative zeros
+          number
+        end
+
+        def round_significant(number)
+          return 0 if number.zero?
+          digits = digit_count(number)
+          multiplier = 10**(digits - precision)
+          (number / BigDecimal(multiplier.to_f.to_s)).round * multiplier
+        end
+
+        def convert_to_decimal(number)
+          case number
+          when Float, String
+            BigDecimal(number.to_s)
+          when Rational
+            BigDecimal(number, digit_count(number.to_i) + precision)
+          else
+            number.to_d
+          end
+        end
+
+        def precision
+          options[:precision]
+        end
+
+        def significant
+          options[:significant]
+        end
+
+        def absolute_number(number)
+          number.respond_to?(:abs) ? number.abs : number.to_d.abs
+        end
+    end
+  end
+end
diff --git a/activesupport/lib/active_support/option_merger.rb b/activesupport/lib/active_support/option_merger.rb
index dea84e437f..ab9ca727f6 100644
--- a/activesupport/lib/active_support/option_merger.rb
+++ b/activesupport/lib/active_support/option_merger.rb
@@ -1,4 +1,6 @@
-require 'active_support/core_ext/hash/deep_merge'
+# frozen_string_literal: true
+
+require "active_support/core_ext/hash/deep_merge"
 
 module ActiveSupport
   class OptionMerger #:nodoc:
diff --git a/activesupport/lib/active_support/ordered_hash.rb b/activesupport/lib/active_support/ordered_hash.rb
index b1658f0f27..5758513021 100644
--- a/activesupport/lib/active_support/ordered_hash.rb
+++ b/activesupport/lib/active_support/ordered_hash.rb
@@ -1,7 +1,9 @@
-require 'yaml'
+# frozen_string_literal: true
+
+require "yaml"
 
 YAML.add_builtin_type("omap") do |type, val|
-  ActiveSupport::OrderedHash[val.map{ |v| v.to_a.first }]
+  ActiveSupport::OrderedHash[val.map { |v| v.to_a.first }]
 end
 
 module ActiveSupport
@@ -25,7 +27,7 @@ module ActiveSupport
     end
 
     def encode_with(coder)
-      coder.represent_seq '!omap', map { |k,v| { k => v } }
+      coder.represent_seq "!omap", map { |k, v| { k => v } }
     end
 
     def select(*args, &block)
diff --git a/activesupport/lib/active_support/ordered_options.rb b/activesupport/lib/active_support/ordered_options.rb
index 501ba7fc76..c4e419f546 100644
--- a/activesupport/lib/active_support/ordered_options.rb
+++ b/activesupport/lib/active_support/ordered_options.rb
@@ -1,4 +1,6 @@
-require 'active_support/core_ext/object/blank'
+# frozen_string_literal: true
+
+require "active_support/core_ext/object/blank"
 
 module ActiveSupport
   # Usually key value pairs are handled something like this:
@@ -22,7 +24,7 @@ module ActiveSupport
   # To raise an exception when the value is blank, append a
   # bang to the key name, like:
   #
-  #   h.dog! # => raises KeyError: key not found: :dog
+  #   h.dog! # => raises KeyError: :dog is blank
   #
   class OrderedOptions < Hash
     alias_method :_get, :[] # preserve the original #[] method
@@ -38,13 +40,13 @@ module ActiveSupport
 
     def method_missing(name, *args)
       name_string = name.to_s
-      if name_string.chomp!('=')
+      if name_string.chomp!("=")
         self[name_string] = args.first
       else
-        bangs = name_string.chomp!('!')
+        bangs = name_string.chomp!("!")
 
         if bangs
-          fetch(name_string.to_sym).presence || raise(KeyError.new("#{name_string} is blank."))
+          self[name_string].presence || raise(KeyError.new(":#{name_string} is blank"))
         else
           self[name_string]
         end
@@ -68,9 +70,9 @@ module ActiveSupport
     def initialize(parent = nil)
       if parent.kind_of?(OrderedOptions)
         # use the faster _get when dealing with OrderedOptions
-        super() { |h,k| parent._get(k) }
+        super() { |h, k| parent._get(k) }
       elsif parent
-        super() { |h,k| parent[k] }
+        super() { |h, k| parent[k] }
       else
         super()
       end
diff --git a/activesupport/lib/active_support/per_thread_registry.rb b/activesupport/lib/active_support/per_thread_registry.rb
index 88e2b12cc7..eb92fb4371 100644
--- a/activesupport/lib/active_support/per_thread_registry.rb
+++ b/activesupport/lib/active_support/per_thread_registry.rb
@@ -1,7 +1,9 @@
-require 'active_support/core_ext/module/delegation'
+# frozen_string_literal: true
+
+require "active_support/core_ext/module/delegation"
 
 module ActiveSupport
-  # NOTE: This approach has been deprecated for end-user code in favor of thread_mattr_accessor and friends.
+  # NOTE: This approach has been deprecated for end-user code in favor of {thread_mattr_accessor}[rdoc-ref:Module#thread_mattr_accessor] and friends.
   # Please use that approach instead.
   #
   # This module is used to encapsulate access to thread local variables.
@@ -38,15 +40,15 @@ module ActiveSupport
   # If the class has an initializer, it must accept no arguments.
   module PerThreadRegistry
     def self.extended(object)
-      object.instance_variable_set '@per_thread_registry_key', object.name.freeze
+      object.instance_variable_set "@per_thread_registry_key", object.name.freeze
     end
 
     def instance
       Thread.current[@per_thread_registry_key] ||= new
     end
 
-    protected
-      def method_missing(name, *args, &block) # :nodoc:
+    private
+      def method_missing(name, *args, &block)
         # Caches the method definition as a singleton method of the receiver.
         #
         # By letting #delegate handle it, we avoid an enclosure that'll capture args.
diff --git a/activesupport/lib/active_support/proxy_object.rb b/activesupport/lib/active_support/proxy_object.rb
index 20a0fd8e62..0965fcd2d9 100644
--- a/activesupport/lib/active_support/proxy_object.rb
+++ b/activesupport/lib/active_support/proxy_object.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActiveSupport
   # A class with no predefined methods that behaves similarly to Builder's
   # BlankSlate. Used for proxy classes.
diff --git a/activesupport/lib/active_support/rails.rb b/activesupport/lib/active_support/rails.rb
index c8e3a4bf53..5c34a0abb3 100644
--- a/activesupport/lib/active_support/rails.rb
+++ b/activesupport/lib/active_support/rails.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 # This is private interface.
 #
 # Rails components cherry pick from Active Support as needed, but there are a
@@ -9,19 +11,25 @@
 # Rails and can change anytime.
 
 # Defines Object#blank? and Object#present?.
-require 'active_support/core_ext/object/blank'
+require "active_support/core_ext/object/blank"
 
 # Rails own autoload, eager_load, etc.
-require 'active_support/dependencies/autoload'
+require "active_support/dependencies/autoload"
 
 # Support for ClassMethods and the included macro.
-require 'active_support/concern'
+require "active_support/concern"
 
 # Defines Class#class_attribute.
-require 'active_support/core_ext/class/attribute'
+require "active_support/core_ext/class/attribute"
 
 # Defines Module#delegate.
-require 'active_support/core_ext/module/delegation'
+require "active_support/core_ext/module/delegation"
 
 # Defines ActiveSupport::Deprecation.
-require 'active_support/deprecation'
+require "active_support/deprecation"
+
+# Defines Regexp#match?.
+#
+# This should be removed when Rails needs Ruby 2.4 or later, and the require
+# added where other Regexp extensions are being used (easy to grep).
+require "active_support/core_ext/regexp"
diff --git a/activesupport/lib/active_support/railtie.rb b/activesupport/lib/active_support/railtie.rb
index 845788b669..91872e29c8 100644
--- a/activesupport/lib/active_support/railtie.rb
+++ b/activesupport/lib/active_support/railtie.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require "active_support"
 require "active_support/i18n_railtie"
 
@@ -7,6 +9,19 @@ module ActiveSupport
 
     config.eager_load_namespaces << ActiveSupport
 
+    initializer "active_support.set_authenticated_message_encryption" do |app|
+      if app.config.active_support.respond_to?(:use_authenticated_message_encryption)
+        ActiveSupport::MessageEncryptor.use_authenticated_message_encryption =
+          app.config.active_support.use_authenticated_message_encryption
+      end
+    end
+
+    initializer "active_support.reset_all_current_attributes_instances" do |app|
+      app.reloader.before_class_unload { ActiveSupport::CurrentAttributes.clear_all }
+      app.executor.to_run              { ActiveSupport::CurrentAttributes.reset_all }
+      app.executor.to_complete         { ActiveSupport::CurrentAttributes.reset_all }
+    end
+
     initializer "active_support.deprecation_behavior" do |app|
       if deprecation = app.config.active_support.deprecation
         ActiveSupport::Deprecation.behavior = deprecation
@@ -21,31 +36,42 @@ module ActiveSupport
       rescue TZInfo::DataSourceNotFound => e
         raise e.exception "tzinfo-data is not present. Please add gem 'tzinfo-data' to your Gemfile and run bundle install"
       end
-      require 'active_support/core_ext/time/zones'
-      zone_default = Time.find_zone!(app.config.time_zone)
-
-      unless zone_default
-        raise 'Value assigned to config.time_zone not recognized. ' \
-          'Run "rake time:zones:all" for a time zone names list.'
-      end
-
-      Time.zone_default = zone_default
+      require "active_support/core_ext/time/zones"
+      Time.zone_default = Time.find_zone!(app.config.time_zone)
     end
 
     # Sets the default week start
     # If assigned value is not a valid day symbol (e.g. :sunday, :monday, ...), an exception will be raised.
     initializer "active_support.initialize_beginning_of_week" do |app|
-      require 'active_support/core_ext/date/calculations'
+      require "active_support/core_ext/date/calculations"
       beginning_of_week_default = Date.find_beginning_of_week!(app.config.beginning_of_week)
 
       Date.beginning_of_week_default = beginning_of_week_default
     end
 
+    initializer "active_support.require_master_key" do |app|
+      if app.config.respond_to?(:require_master_key) && app.config.require_master_key
+        begin
+          app.credentials.key
+        rescue ActiveSupport::EncryptedFile::MissingKeyError => error
+          $stderr.puts error.message
+          exit 1
+        end
+      end
+    end
+
     initializer "active_support.set_configs" do |app|
       app.config.active_support.each do |k, v|
         k = "#{k}="
         ActiveSupport.send(k, v) if ActiveSupport.respond_to? k
       end
     end
+
+    initializer "active_support.set_hash_digest_class" do |app|
+      if app.config.active_support.respond_to?(:hash_digest_class) && app.config.active_support.hash_digest_class
+        ActiveSupport::Digest.hash_digest_class =
+          app.config.active_support.hash_digest_class
+      end
+    end
   end
 end
diff --git a/activesupport/lib/active_support/reloader.rb b/activesupport/lib/active_support/reloader.rb
index 5623bdd349..b26d9c3665 100644
--- a/activesupport/lib/active_support/reloader.rb
+++ b/activesupport/lib/active_support/reloader.rb
@@ -1,4 +1,6 @@
-require 'active_support/execution_wrapper'
+# frozen_string_literal: true
+
+require "active_support/execution_wrapper"
 
 module ActiveSupport
   #--
@@ -26,14 +28,17 @@ module ActiveSupport
 
     define_callbacks :class_unload
 
+    # Registers a callback that will run once at application startup and every time the code is reloaded.
     def self.to_prepare(*args, &block)
       set_callback(:prepare, *args, &block)
     end
 
+    # Registers a callback that will run immediately before the classes are unloaded.
     def self.before_class_unload(*args, &block)
       set_callback(:class_unload, *args, &block)
     end
 
+    # Registers a callback that will run immediately after the classes are unloaded.
     def self.after_class_unload(*args, &block)
       set_callback(:class_unload, :after, *args, &block)
     end
@@ -69,11 +74,8 @@ module ActiveSupport
       end
     end
 
-    class_attribute :executor
-    class_attribute :check
-
-    self.executor = Executor
-    self.check = lambda { false }
+    class_attribute :executor, default: Executor
+    class_attribute :check, default: lambda { false }
 
     def self.check! # :nodoc:
       @should_reload ||= check.call
diff --git a/activesupport/lib/active_support/rescuable.rb b/activesupport/lib/active_support/rescuable.rb
index 2c05deee41..e0fa29cacb 100644
--- a/activesupport/lib/active_support/rescuable.rb
+++ b/activesupport/lib/active_support/rescuable.rb
@@ -1,6 +1,8 @@
-require 'active_support/concern'
-require 'active_support/core_ext/class/attribute'
-require 'active_support/core_ext/string/inflections'
+# frozen_string_literal: true
+
+require "active_support/concern"
+require "active_support/core_ext/class/attribute"
+require "active_support/core_ext/string/inflections"
 
 module ActiveSupport
   # Rescuable module adds support for easier exception handling.
@@ -8,8 +10,7 @@ module ActiveSupport
     extend Concern
 
     included do
-      class_attribute :rescue_handlers
-      self.rescue_handlers = []
+      class_attribute :rescue_handlers, default: []
     end
 
     module ClassMethods
@@ -36,7 +37,7 @@ module ActiveSupport
       #       render xml: exception, status: 500
       #     end
       #
-      #     protected
+      #     private
       #       def deny_access
       #         ...
       #       end
@@ -52,7 +53,7 @@ module ActiveSupport
           if block_given?
             with = block
           else
-            raise ArgumentError, 'Need a handler. Pass the with: keyword argument or provide a block.'
+            raise ArgumentError, "Need a handler. Pass the with: keyword argument or provide a block."
           end
         end
 
@@ -74,7 +75,7 @@ module ActiveSupport
       #
       # If no handler matches the exception, check for a handler matching the
       # (optional) exception.cause. If no handler matches the exception or its
-      # cause, this returns nil so you can deal with unhandled exceptions.
+      # cause, this returns +nil+, so you can deal with unhandled exceptions.
       # Be sure to re-raise unhandled exceptions if this is what you expect.
       #
       #     begin
@@ -83,11 +84,19 @@ module ActiveSupport
       #       rescue_with_handler(exception) || raise
       #     end
       #
-      # Returns the exception if it was handled and nil if it was not.
-      def rescue_with_handler(exception, object: self)
+      # Returns the exception if it was handled and +nil+ if it was not.
+      def rescue_with_handler(exception, object: self, visited_exceptions: [])
+        visited_exceptions << exception
+
         if handler = handler_for_rescue(exception, object: object)
           handler.call exception
           exception
+        elsif exception
+          if visited_exceptions.include?(exception.cause)
+            nil
+          else
+            rescue_with_handler(exception.cause, object: object, visited_exceptions: visited_exceptions)
+          end
         end
       end
 
@@ -121,7 +130,7 @@ module ActiveSupport
               end
             end
 
-            handler || find_rescue_handler(exception.cause)
+            handler
           end
         end
 
diff --git a/activesupport/lib/active_support/security_utils.rb b/activesupport/lib/active_support/security_utils.rb
index 9be8613ada..20b6b9cd3f 100644
--- a/activesupport/lib/active_support/security_utils.rb
+++ b/activesupport/lib/active_support/security_utils.rb
@@ -1,15 +1,15 @@
-require 'digest'
+# frozen_string_literal: true
+
+require "digest/sha2"
 
 module ActiveSupport
   module SecurityUtils
-    # Constant time string comparison.
+    # Constant time string comparison, for fixed length strings.
     #
     # The values compared should be of fixed length, such as strings
-    # that have already been processed by HMAC. This should not be used
-    # on variable length plaintext strings because it could leak length info
-    # via timing attacks.
-    def secure_compare(a, b)
-      return false unless a.bytesize == b.bytesize
+    # that have already been processed by HMAC. Raises in case of length mismatch.
+    def fixed_length_secure_compare(a, b)
+      raise ArgumentError, "string length mismatch." unless a.bytesize == b.bytesize
 
       l = a.unpack "C#{a.bytesize}"
 
@@ -17,11 +17,15 @@ module ActiveSupport
       b.each_byte { |byte| res |= byte ^ l.shift }
       res == 0
     end
-    module_function :secure_compare
+    module_function :fixed_length_secure_compare
 
-    def variable_size_secure_compare(a, b) # :nodoc:
-      secure_compare(::Digest::SHA256.hexdigest(a), ::Digest::SHA256.hexdigest(b))
+    # Constant time string comparison, for variable length strings.
+    #
+    # The values are first processed by SHA256, so that we don't leak length info
+    # via timing attacks.
+    def secure_compare(a, b)
+      fixed_length_secure_compare(::Digest::SHA256.hexdigest(a), ::Digest::SHA256.hexdigest(b)) && a == b
     end
-    module_function :variable_size_secure_compare
+    module_function :secure_compare
   end
 end
diff --git a/activesupport/lib/active_support/string_inquirer.rb b/activesupport/lib/active_support/string_inquirer.rb
index bc673150d0..a3af36720e 100644
--- a/activesupport/lib/active_support/string_inquirer.rb
+++ b/activesupport/lib/active_support/string_inquirer.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActiveSupport
   # Wrapping a string in this class gives you a prettier way to test
   # for equality. The value returned by <tt>Rails.env</tt> is wrapped
@@ -8,15 +10,21 @@ module ActiveSupport
   # you can call this:
   #
   #   Rails.env.production?
+  #
+  # == Instantiating a new StringInquirer
+  #
+  #   vehicle = ActiveSupport::StringInquirer.new('car')
+  #   vehicle.car?   # => true
+  #   vehicle.bike?  # => false
   class StringInquirer < String
     private
 
       def respond_to_missing?(method_name, include_private = false)
-        method_name[-1] == '?'
+        (method_name[-1] == "?") || super
       end
 
       def method_missing(method_name, *arguments)
-        if method_name[-1] == '?'
+        if method_name[-1] == "?"
           self == method_name[0..-2]
         else
           super
diff --git a/activesupport/lib/active_support/subscriber.rb b/activesupport/lib/active_support/subscriber.rb
index 1cd4b807ad..d6dd5474d0 100644
--- a/activesupport/lib/active_support/subscriber.rb
+++ b/activesupport/lib/active_support/subscriber.rb
@@ -1,4 +1,7 @@
-require 'active_support/per_thread_registry'
+# frozen_string_literal: true
+
+require "active_support/per_thread_registry"
+require "active_support/notifications"
 
 module ActiveSupport
   # ActiveSupport::Subscriber is an object set to consume
@@ -23,9 +26,8 @@ module ActiveSupport
   # the +sql+ method.
   class Subscriber
     class << self
-
       # Attach the subscriber to a namespace.
-      def attach_to(namespace, subscriber=new, notifier=ActiveSupport::Notifications)
+      def attach_to(namespace, subscriber = new, notifier = ActiveSupport::Notifications)
         @namespace  = namespace
         @subscriber = subscriber
         @notifier   = notifier
@@ -52,11 +54,15 @@ module ActiveSupport
         @@subscribers ||= []
       end
 
+      # TODO Change this to private once we've dropped Ruby 2.2 support.
+      # Workaround for Ruby 2.2 "private attribute?" warning.
       protected
 
       attr_reader :subscriber, :notifier, :namespace
 
-      def add_event_subscriber(event)
+      private
+
+      def add_event_subscriber(event) # :doc:
         return if %w{ start finish }.include?(event.to_s)
 
         pattern = "#{event}.#{namespace}"
@@ -91,7 +97,7 @@ module ActiveSupport
       event.end = finished
       event.payload.merge!(payload)
 
-      method = name.split('.'.freeze).first
+      method = name.split(".".freeze).first
       send(method, event)
     end
 
diff --git a/activesupport/lib/active_support/tagged_logging.rb b/activesupport/lib/active_support/tagged_logging.rb
index bcd7bf74c0..8561cba9f1 100644
--- a/activesupport/lib/active_support/tagged_logging.rb
+++ b/activesupport/lib/active_support/tagged_logging.rb
@@ -1,7 +1,9 @@
-require 'active_support/core_ext/module/delegation'
-require 'active_support/core_ext/object/blank'
-require 'logger'
-require 'active_support/logger'
+# frozen_string_literal: true
+
+require "active_support/core_ext/module/delegation"
+require "active_support/core_ext/object/blank"
+require "logger"
+require "active_support/logger"
 
 module ActiveSupport
   # Wraps any standard Logger object to provide tagging capabilities.
@@ -48,13 +50,12 @@ module ActiveSupport
         Thread.current[thread_key] ||= []
       end
 
-      private
-        def tags_text
-          tags = current_tags
-          if tags.any?
-            tags.collect { |tag| "[#{tag}] " }.join
-          end
+      def tags_text
+        tags = current_tags
+        if tags.any?
+          tags.collect { |tag| "[#{tag}] " }.join
         end
+      end
     end
 
     def self.new(logger)
diff --git a/activesupport/lib/active_support/test_case.rb b/activesupport/lib/active_support/test_case.rb
index 221e1171e7..d1f7e6ea09 100644
--- a/activesupport/lib/active_support/test_case.rb
+++ b/activesupport/lib/active_support/test_case.rb
@@ -1,15 +1,16 @@
-gem 'minitest' # make sure we get the gem, not stdlib
-require 'minitest'
-require 'active_support/testing/tagged_logging'
-require 'active_support/testing/setup_and_teardown'
-require 'active_support/testing/assertions'
-require 'active_support/testing/deprecation'
-require 'active_support/testing/declarative'
-require 'active_support/testing/isolation'
-require 'active_support/testing/constant_lookup'
-require 'active_support/testing/time_helpers'
-require 'active_support/testing/file_fixtures'
-require 'active_support/core_ext/kernel/reporting'
+# frozen_string_literal: true
+
+gem "minitest" # make sure we get the gem, not stdlib
+require "minitest"
+require "active_support/testing/tagged_logging"
+require "active_support/testing/setup_and_teardown"
+require "active_support/testing/assertions"
+require "active_support/testing/deprecation"
+require "active_support/testing/declarative"
+require "active_support/testing/isolation"
+require "active_support/testing/constant_lookup"
+require "active_support/testing/time_helpers"
+require "active_support/testing/file_fixtures"
 
 module ActiveSupport
   class TestCase < ::Minitest::Test
@@ -66,16 +67,6 @@ module ActiveSupport
     alias :assert_not_respond_to :refute_respond_to
     alias :assert_not_same :refute_same
 
-
-    # Assertion that the block should not raise an exception.
-    #
-    # Passes if evaluated code in the yielded block raises no exception.
-    #
-    #   assert_nothing_raised do
-    #     perform_service(param: 'no_exception')
-    #   end
-    def assert_nothing_raised
-      yield
-    end
+    ActiveSupport.run_load_hooks(:active_support_test_case, self)
   end
 end
diff --git a/activesupport/lib/active_support/testing/assertions.rb b/activesupport/lib/active_support/testing/assertions.rb
index ad83638572..b24aa36ede 100644
--- a/activesupport/lib/active_support/testing/assertions.rb
+++ b/activesupport/lib/active_support/testing/assertions.rb
@@ -1,6 +1,10 @@
+# frozen_string_literal: true
+
 module ActiveSupport
   module Testing
     module Assertions
+      UNTRACKED = Object.new # :nodoc:
+
       # Asserts that an expression is not truthy. Passes if <tt>object</tt> is
       # +nil+ or +false+. "Truthy" means "considered true in a conditional"
       # like <tt>if foo</tt>.
@@ -17,6 +21,17 @@ module ActiveSupport
         assert !object, message
       end
 
+      # Assertion that the block should not raise an exception.
+      #
+      # Passes if evaluated code in the yielded block raises no exception.
+      #
+      #   assert_nothing_raised do
+      #     perform_service(param: 'no_exception')
+      #   end
+      def assert_nothing_raised
+        yield
+      end
+
       # Test numeric difference between the return value of an expression as a
       # result of what is evaluated in the yielded block.
       #
@@ -92,6 +107,93 @@ module ActiveSupport
       def assert_no_difference(expression, message = nil, &block)
         assert_difference expression, 0, message, &block
       end
+
+      # Assertion that the result of evaluating an expression is changed before
+      # and after invoking the passed in block.
+      #
+      #   assert_changes 'Status.all_good?' do
+      #     post :create, params: { status: { ok: false } }
+      #   end
+      #
+      # You can pass the block as a string to be evaluated in the context of
+      # the block. A lambda can be passed for the block as well.
+      #
+      #   assert_changes -> { Status.all_good? } do
+      #     post :create, params: { status: { ok: false } }
+      #   end
+      #
+      # The assertion is useful to test side effects. The passed block can be
+      # anything that can be converted to string with #to_s.
+      #
+      #   assert_changes :@object do
+      #     @object = 42
+      #   end
+      #
+      # The keyword arguments :from and :to can be given to specify the
+      # expected initial value and the expected value after the block was
+      # executed.
+      #
+      #   assert_changes :@object, from: nil, to: :foo do
+      #     @object = :foo
+      #   end
+      #
+      # An error message can be specified.
+      #
+      #   assert_changes -> { Status.all_good? }, 'Expected the status to be bad' do
+      #     post :create, params: { status: { incident: true } }
+      #   end
+      def assert_changes(expression, message = nil, from: UNTRACKED, to: UNTRACKED, &block)
+        exp = expression.respond_to?(:call) ? expression : -> { eval(expression.to_s, block.binding) }
+
+        before = exp.call
+        retval = yield
+
+        unless from == UNTRACKED
+          error = "#{expression.inspect} isn't #{from.inspect}"
+          error = "#{message}.\n#{error}" if message
+          assert from === before, error
+        end
+
+        after = exp.call
+
+        if to == UNTRACKED
+          error = "#{expression.inspect} didn't change"
+          error = "#{message}.\n#{error}" if message
+          assert before != after, error
+        else
+          error = "#{expression.inspect} didn't change to #{to}"
+          error = "#{message}.\n#{error}" if message
+          assert to === after, error
+        end
+
+        retval
+      end
+
+      # Assertion that the result of evaluating an expression is not changed before
+      # and after invoking the passed in block.
+      #
+      #   assert_no_changes 'Status.all_good?' do
+      #     post :create, params: { status: { ok: true } }
+      #   end
+      #
+      # An error message can be specified.
+      #
+      #   assert_no_changes -> { Status.all_good? }, 'Expected the status to be good' do
+      #     post :create, params: { status: { ok: false } }
+      #   end
+      def assert_no_changes(expression, message = nil, &block)
+        exp = expression.respond_to?(:call) ? expression : -> { eval(expression.to_s, block.binding) }
+
+        before = exp.call
+        retval = yield
+        after = exp.call
+
+        error = "#{expression.inspect} did change to #{after}"
+        error = "#{message}.\n#{error}" if message
+        assert before == after, error
+
+        retval
+      end
     end
   end
 end
diff --git a/activesupport/lib/active_support/testing/autorun.rb b/activesupport/lib/active_support/testing/autorun.rb
index 84c6b89340..889b41659a 100644
--- a/activesupport/lib/active_support/testing/autorun.rb
+++ b/activesupport/lib/active_support/testing/autorun.rb
@@ -1,12 +1,7 @@
-gem 'minitest'
+# frozen_string_literal: true
 
-require 'minitest'
+gem "minitest"
 
-if Minitest.respond_to?(:run_with_rails_extension)
-  unless Minitest.run_with_rails_extension
-    Minitest.run_with_autorun = true
-    Minitest.autorun
-  end
-else
-  Minitest.autorun
-end
+require "minitest"
+
+Minitest.autorun
diff --git a/activesupport/lib/active_support/testing/constant_lookup.rb b/activesupport/lib/active_support/testing/constant_lookup.rb
index 07d477c0db..51167e9237 100644
--- a/activesupport/lib/active_support/testing/constant_lookup.rb
+++ b/activesupport/lib/active_support/testing/constant_lookup.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require "active_support/concern"
 require "active_support/inflector"
 
@@ -44,7 +46,6 @@ module ActiveSupport
           end
         end
       end
-
     end
   end
 end
diff --git a/activesupport/lib/active_support/testing/declarative.rb b/activesupport/lib/active_support/testing/declarative.rb
index 0bf3643a56..7c3403684d 100644
--- a/activesupport/lib/active_support/testing/declarative.rb
+++ b/activesupport/lib/active_support/testing/declarative.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActiveSupport
   module Testing
     module Declarative
@@ -9,7 +11,7 @@ module ActiveSupport
         #     ...
         #   end
         def test(name, &block)
-          test_name = "test_#{name.gsub(/\s+/,'_')}".to_sym
+          test_name = "test_#{name.gsub(/\s+/, '_')}".to_sym
           defined = method_defined? test_name
           raise "#{test_name} is already defined in #{self}" if defined
           if block_given?
diff --git a/activesupport/lib/active_support/testing/deprecation.rb b/activesupport/lib/active_support/testing/deprecation.rb
index 5dfa14eeba..f655435729 100644
--- a/activesupport/lib/active_support/testing/deprecation.rb
+++ b/activesupport/lib/active_support/testing/deprecation.rb
@@ -1,4 +1,7 @@
-require 'active_support/deprecation'
+# frozen_string_literal: true
+
+require "active_support/deprecation"
+require "active_support/core_ext/regexp"
 
 module ActiveSupport
   module Testing
@@ -8,7 +11,7 @@ module ActiveSupport
         assert !warnings.empty?, "Expected a deprecation warning within the block but received none"
         if match
           match = Regexp.new(Regexp.escape(match)) unless match.is_a?(Regexp)
-          assert warnings.any? { |w| w =~ match }, "No deprecation warning matched #{match}: #{warnings.join(', ')}"
+          assert warnings.any? { |w| match.match?(w) }, "No deprecation warning matched #{match}: #{warnings.join(', ')}"
         end
         result
       end
diff --git a/activesupport/lib/active_support/testing/file_fixtures.rb b/activesupport/lib/active_support/testing/file_fixtures.rb
index affb84cda5..ad923d1aab 100644
--- a/activesupport/lib/active_support/testing/file_fixtures.rb
+++ b/activesupport/lib/active_support/testing/file_fixtures.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActiveSupport
   module Testing
     # Adds simple access to sample files called file fixtures.
diff --git a/activesupport/lib/active_support/testing/isolation.rb b/activesupport/lib/active_support/testing/isolation.rb
index 7dd03ce65d..fa9bebb181 100644
--- a/activesupport/lib/active_support/testing/isolation.rb
+++ b/activesupport/lib/active_support/testing/isolation.rb
@@ -1,7 +1,9 @@
+# frozen_string_literal: true
+
 module ActiveSupport
   module Testing
     module Isolation
-      require 'thread'
+      require "thread"
 
       def self.included(klass) #:nodoc:
         klass.class_eval do
@@ -43,7 +45,7 @@ module ActiveSupport
                   end
                 }
               end
-              result = Marshal.dump(self.dup)
+              result = Marshal.dump(dup)
             end
 
             write.puts [result].pack("m")
@@ -53,7 +55,7 @@ module ActiveSupport
           write.close
           result = read.read
           Process.wait2(pid)
-          return result.unpack("m")[0]
+          result.unpack("m")[0]
         end
       end
 
@@ -68,23 +70,25 @@ module ActiveSupport
           if ENV["ISOLATION_TEST"]
             yield
             File.open(ENV["ISOLATION_OUTPUT"], "w") do |file|
-              file.puts [Marshal.dump(self.dup)].pack("m")
+              file.puts [Marshal.dump(dup)].pack("m")
             end
             exit!
           else
             Tempfile.open("isolation") do |tmpfile|
               env = {
-                'ISOLATION_TEST' => self.class.name,
-                'ISOLATION_OUTPUT' => tmpfile.path
+                "ISOLATION_TEST" => self.class.name,
+                "ISOLATION_OUTPUT" => tmpfile.path
               }
 
-              load_paths = $-I.map {|p| "-I\"#{File.expand_path(p)}\"" }.join(" ")
-              orig_args = ORIG_ARGV.join(" ")
-              test_opts = "-n#{self.class.name}##{self.name}"
-              command = "#{Gem.ruby} #{load_paths} #{$0} '#{orig_args}' #{test_opts}"
+              test_opts = "-n#{self.class.name}##{name}"
+
+              load_path_args = []
+              $-I.each do |p|
+                load_path_args << "-I"
+                load_path_args << File.expand_path(p)
+              end
 
-              # IO.popen lets us pass env in a cross-platform way
-              child = IO.popen(env, command)
+              child = IO.popen([env, Gem.ruby, *load_path_args, $0, *ORIG_ARGV, test_opts])
 
               begin
                 Process.wait(child.pid)
diff --git a/activesupport/lib/active_support/testing/method_call_assertions.rb b/activesupport/lib/active_support/testing/method_call_assertions.rb
index fccaa54f40..c6358002ea 100644
--- a/activesupport/lib/active_support/testing/method_call_assertions.rb
+++ b/activesupport/lib/active_support/testing/method_call_assertions.rb
@@ -1,4 +1,6 @@
-require 'minitest/mock'
+# frozen_string_literal: true
+
+require "minitest/mock"
 
 module ActiveSupport
   module Testing
diff --git a/activesupport/lib/active_support/testing/setup_and_teardown.rb b/activesupport/lib/active_support/testing/setup_and_teardown.rb
index 33f2b8dc9b..1dbf3c5da0 100644
--- a/activesupport/lib/active_support/testing/setup_and_teardown.rb
+++ b/activesupport/lib/active_support/testing/setup_and_teardown.rb
@@ -1,5 +1,7 @@
-require 'active_support/concern'
-require 'active_support/callbacks'
+# frozen_string_literal: true
+
+require "active_support/concern"
+require "active_support/callbacks"
 
 module ActiveSupport
   module Testing
diff --git a/activesupport/lib/active_support/testing/stream.rb b/activesupport/lib/active_support/testing/stream.rb
index 895192ad05..d070a1793d 100644
--- a/activesupport/lib/active_support/testing/stream.rb
+++ b/activesupport/lib/active_support/testing/stream.rb
@@ -1,42 +1,44 @@
+# frozen_string_literal: true
+
 module ActiveSupport
   module Testing
     module Stream #:nodoc:
       private
 
-      def silence_stream(stream)
-        old_stream = stream.dup
-        stream.reopen(IO::NULL)
-        stream.sync = true
-        yield
-      ensure
-        stream.reopen(old_stream)
-        old_stream.close
-      end
+        def silence_stream(stream)
+          old_stream = stream.dup
+          stream.reopen(IO::NULL)
+          stream.sync = true
+          yield
+        ensure
+          stream.reopen(old_stream)
+          old_stream.close
+        end
 
-      def quietly
-        silence_stream(STDOUT) do
-          silence_stream(STDERR) do
-            yield
+        def quietly
+          silence_stream(STDOUT) do
+            silence_stream(STDERR) do
+              yield
+            end
           end
         end
-      end
 
-      def capture(stream)
-        stream = stream.to_s
-        captured_stream = Tempfile.new(stream)
-        stream_io = eval("$#{stream}")
-        origin_stream = stream_io.dup
-        stream_io.reopen(captured_stream)
+        def capture(stream)
+          stream = stream.to_s
+          captured_stream = Tempfile.new(stream)
+          stream_io = eval("$#{stream}")
+          origin_stream = stream_io.dup
+          stream_io.reopen(captured_stream)
 
-        yield
+          yield
 
-        stream_io.rewind
-        return captured_stream.read
-      ensure
-        captured_stream.close
-        captured_stream.unlink
-        stream_io.reopen(origin_stream)
-      end
+          stream_io.rewind
+          return captured_stream.read
+        ensure
+          captured_stream.close
+          captured_stream.unlink
+          stream_io.reopen(origin_stream)
+        end
     end
   end
 end
diff --git a/activesupport/lib/active_support/testing/tagged_logging.rb b/activesupport/lib/active_support/testing/tagged_logging.rb
index 843ce4a867..9ca50c7918 100644
--- a/activesupport/lib/active_support/testing/tagged_logging.rb
+++ b/activesupport/lib/active_support/testing/tagged_logging.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActiveSupport
   module Testing
     # Logs a "PostsControllerTest: test name" heading before each test to
@@ -8,7 +10,7 @@ module ActiveSupport
       def before_setup
         if tagged_logger && tagged_logger.info?
           heading = "#{self.class}: #{name}"
-          divider = '-' * heading.size
+          divider = "-" * heading.size
           tagged_logger.info divider
           tagged_logger.info heading
           tagged_logger.info divider
diff --git a/activesupport/lib/active_support/testing/time_helpers.rb b/activesupport/lib/active_support/testing/time_helpers.rb
index fca0947c5b..998a51a34c 100644
--- a/activesupport/lib/active_support/testing/time_helpers.rb
+++ b/activesupport/lib/active_support/testing/time_helpers.rb
@@ -1,39 +1,50 @@
+# frozen_string_literal: true
+
+require "active_support/core_ext/module/redefine_method"
+require "active_support/core_ext/string/strip" # for strip_heredoc
+require "active_support/core_ext/time/calculations"
+require "concurrent/map"
+
 module ActiveSupport
   module Testing
     class SimpleStubs # :nodoc:
       Stub = Struct.new(:object, :method_name, :original_method)
 
       def initialize
-        @stubs = {}
+        @stubs = Concurrent::Map.new { |h, k| h[k] = {} }
       end
 
-      def stub_object(object, method_name, return_value)
-        key = [object.object_id, method_name]
-
-        if stub = @stubs[key]
+      def stub_object(object, method_name, &block)
+        if stub = stubbing(object, method_name)
           unstub_object(stub)
         end
 
         new_name = "__simple_stub__#{method_name}"
 
-        @stubs[key] = Stub.new(object, method_name, new_name)
+        @stubs[object.object_id][method_name] = Stub.new(object, method_name, new_name)
 
         object.singleton_class.send :alias_method, new_name, method_name
-        object.define_singleton_method(method_name) { return_value }
+        object.define_singleton_method(method_name, &block)
       end
 
       def unstub_all!
-        @stubs.each_value do |stub|
-          unstub_object(stub)
+        @stubs.each_value do |object_stubs|
+          object_stubs.each_value do |stub|
+            unstub_object(stub)
+          end
         end
-        @stubs = {}
+        @stubs.clear
+      end
+
+      def stubbing(object, method_name)
+        @stubs[object.object_id][method_name]
       end
 
       private
 
         def unstub_object(stub)
           singleton_class = stub.object.singleton_class
-          singleton_class.send :undef_method, stub.method_name
+          singleton_class.send :silence_redefinition_of_method, stub.method_name
           singleton_class.send :alias_method, stub.method_name, stub.original_method
           singleton_class.send :undef_method, stub.original_method
         end
@@ -41,8 +52,14 @@ module ActiveSupport
 
     # Contains helpers that help you test passage of time.
     module TimeHelpers
+      def after_teardown
+        travel_back
+        super
+      end
+
       # Changes current time to the time in the future or in the past by a given time difference by
-      # stubbing +Time.now+, +Date.today+, and +DateTime.now+.
+      # stubbing +Time.now+, +Date.today+, and +DateTime.now+. The stubs are automatically removed
+      # at the end of the test.
       #
       #   Time.current     # => Sat, 09 Nov 2013 15:34:49 EST -05:00
       #   travel 1.day
@@ -64,9 +81,10 @@ module ActiveSupport
 
       # Changes current time to the given time by stubbing +Time.now+,
       # +Date.today+, and +DateTime.now+ to return the time or date passed into this method.
+      # The stubs are automatically removed at the end of the test.
       #
       #   Time.current     # => Sat, 09 Nov 2013 15:34:49 EST -05:00
-      #   travel_to Time.new(2004, 11, 24, 01, 04, 44)
+      #   travel_to Time.zone.local(2004, 11, 24, 01, 04, 44)
       #   Time.current     # => Wed, 24 Nov 2004 01:04:44 EST -05:00
       #   Date.current     # => Wed, 24 Nov 2004
       #   DateTime.current # => Wed, 24 Nov 2004 01:04:44 -0500
@@ -88,20 +106,48 @@ module ActiveSupport
       # state at the end of the block:
       #
       #   Time.current # => Sat, 09 Nov 2013 15:34:49 EST -05:00
-      #   travel_to Time.new(2004, 11, 24, 01, 04, 44) do
+      #   travel_to Time.zone.local(2004, 11, 24, 01, 04, 44) do
       #     Time.current # => Wed, 24 Nov 2004 01:04:44 EST -05:00
       #   end
       #   Time.current # => Sat, 09 Nov 2013 15:34:49 EST -05:00
       def travel_to(date_or_time)
+        if block_given? && simple_stubs.stubbing(Time, :now)
+          travel_to_nested_block_call = <<-MSG.strip_heredoc
+
+      Calling `travel_to` with a block, when we have previously already made a call to `travel_to`, can lead to confusing time stubbing.
+
+      Instead of:
+
+         travel_to 2.days.from_now do
+           # 2 days from today
+           travel_to 3.days.from_now do
+             # 5 days from today
+           end
+         end
+
+      preferred way to achieve above is:
+
+         travel 2.days do
+           # 2 days from today
+         end
+
+         travel 5.days do
+           # 5 days from today
+         end
+
+          MSG
+          raise travel_to_nested_block_call
+        end
+
         if date_or_time.is_a?(Date) && !date_or_time.is_a?(DateTime)
           now = date_or_time.midnight.to_time
         else
           now = date_or_time.to_time.change(usec: 0)
         end
 
-        simple_stubs.stub_object(Time, :now, now)
-        simple_stubs.stub_object(Date, :today, now.to_date)
-        simple_stubs.stub_object(DateTime, :now, now.to_datetime)
+        simple_stubs.stub_object(Time, :now) { at(now.to_i) }
+        simple_stubs.stub_object(Date, :today) { jd(now.to_date.jd) }
+        simple_stubs.stub_object(DateTime, :now) { jd(now.to_date.jd, now.hour, now.min, now.sec, Rational(now.utc_offset, 86400)) }
 
         if block_given?
           begin
@@ -113,10 +159,10 @@ module ActiveSupport
       end
 
       # Returns the current time back to its original state, by removing the stubs added by
-      # `travel` and `travel_to`.
+      # +travel+ and +travel_to+.
       #
       #   Time.current # => Sat, 09 Nov 2013 15:34:49 EST -05:00
-      #   travel_to Time.new(2004, 11, 24, 01, 04, 44)
+      #   travel_to Time.zone.local(2004, 11, 24, 01, 04, 44)
       #   Time.current # => Wed, 24 Nov 2004 01:04:44 EST -05:00
       #   travel_back
       #   Time.current # => Sat, 09 Nov 2013 15:34:49 EST -05:00
@@ -124,6 +170,26 @@ module ActiveSupport
         simple_stubs.unstub_all!
       end
 
+      # Calls +travel_to+ with +Time.now+.
+      #
+      #   Time.current # => Sun, 09 Jul 2017 15:34:49 EST -05:00
+      #   freeze_time
+      #   sleep(1)
+      #   Time.current # => Sun, 09 Jul 2017 15:34:49 EST -05:00
+      #
+      # This method also accepts a block, which will return the current time back to its original
+      # state at the end of the block:
+      #
+      #   Time.current # => Sun, 09 Jul 2017 15:34:49 EST -05:00
+      #   freeze_time do
+      #     sleep(1)
+      #     User.create.created_at # => Sun, 09 Jul 2017 15:34:49 EST -05:00
+      #   end
+      #   Time.current # => Sun, 09 Jul 2017 15:34:50 EST -05:00
+      def freeze_time(&block)
+        travel_to Time.now, &block
+      end
+
       private
 
         def simple_stubs
diff --git a/activesupport/lib/active_support/time.rb b/activesupport/lib/active_support/time.rb
index ea2d3391bd..51854675bf 100644
--- a/activesupport/lib/active_support/time.rb
+++ b/activesupport/lib/active_support/time.rb
@@ -1,18 +1,20 @@
+# frozen_string_literal: true
+
 module ActiveSupport
-  autoload :Duration, 'active_support/duration'
-  autoload :TimeWithZone, 'active_support/time_with_zone'
-  autoload :TimeZone, 'active_support/values/time_zone'
+  autoload :Duration, "active_support/duration"
+  autoload :TimeWithZone, "active_support/time_with_zone"
+  autoload :TimeZone, "active_support/values/time_zone"
 end
 
-require 'date'
-require 'time'
+require "date"
+require "time"
 
-require 'active_support/core_ext/time'
-require 'active_support/core_ext/date'
-require 'active_support/core_ext/date_time'
+require "active_support/core_ext/time"
+require "active_support/core_ext/date"
+require "active_support/core_ext/date_time"
 
-require 'active_support/core_ext/integer/time'
-require 'active_support/core_ext/numeric/time'
+require "active_support/core_ext/integer/time"
+require "active_support/core_ext/numeric/time"
 
-require 'active_support/core_ext/string/conversions'
-require 'active_support/core_ext/string/zones'
+require "active_support/core_ext/string/conversions"
+require "active_support/core_ext/string/zones"
diff --git a/activesupport/lib/active_support/time_with_zone.rb b/activesupport/lib/active_support/time_with_zone.rb
index b1cec43124..20650ce714 100644
--- a/activesupport/lib/active_support/time_with_zone.rb
+++ b/activesupport/lib/active_support/time_with_zone.rb
@@ -1,7 +1,9 @@
-require 'active_support/duration'
-require 'active_support/values/time_zone'
-require 'active_support/core_ext/object/acts_like'
-require 'active_support/core_ext/date_and_time/compatibility'
+# frozen_string_literal: true
+
+require "active_support/duration"
+require "active_support/values/time_zone"
+require "active_support/core_ext/object/acts_like"
+require "active_support/core_ext/date_and_time/compatibility"
 
 module ActiveSupport
   # A Time-like class that can represent a time in any time zone. Necessary
@@ -36,14 +38,13 @@ module ActiveSupport
   #   t.is_a?(Time)                         # => true
   #   t.is_a?(ActiveSupport::TimeWithZone)  # => true
   class TimeWithZone
-
     # Report class name as 'Time' to thwart type checking.
     def self.name
-      'Time'
+      "Time"
     end
 
     PRECISIONS = Hash.new { |h, n| h[n] = "%FT%T.%#{n}N".freeze }
-    PRECISIONS[0] = '%FT%T'.freeze
+    PRECISIONS[0] = "%FT%T".freeze
 
     include Comparable, DateAndTime::Compatibility
     attr_reader :time_zone
@@ -134,7 +135,7 @@ module ActiveSupport
       period.zone_identifier.to_s
     end
 
-    # Returns a string of the object's date, time, zone and offset from UTC.
+    # Returns a string of the object's date, time, zone, and offset from UTC.
     #
     #   Time.zone.now.inspect # => "Thu, 04 Dec 2014 11:00:25 EST -05:00"
     def inspect
@@ -149,6 +150,7 @@ module ActiveSupport
       "#{time.strftime(PRECISIONS[fraction_digits.to_i])}#{formatted_offset(true, 'Z'.freeze)}"
     end
     alias_method :iso8601, :xmlschema
+    alias_method :rfc3339, :xmlschema
 
     # Coerces time to a string for JSON encoding. The default format is ISO 8601.
     # You can get %Y/%m/%d %H:%M:%S +offset style by setting
@@ -171,12 +173,12 @@ module ActiveSupport
     end
 
     def init_with(coder) #:nodoc:
-      initialize(coder['utc'], coder['zone'], coder['time'])
+      initialize(coder["utc"], coder["zone"], coder["time"])
     end
 
     def encode_with(coder) #:nodoc:
-      coder.tag = '!ruby/object:ActiveSupport::TimeWithZone'
-      coder.map = { 'utc' => utc, 'zone' => time_zone, 'time' => time }
+      coder.tag = "!ruby/object:ActiveSupport::TimeWithZone"
+      coder.map = { "utc" => utc, "zone" => time_zone, "time" => time }
     end
 
     # Returns a string of the object's date and time in the format used by
@@ -280,6 +282,7 @@ module ActiveSupport
       end
     end
     alias_method :since, :+
+    alias_method :in, :+
 
     # Returns a new TimeWithZone object that represents the difference between
     # the current object's time and the +other+ time.
@@ -329,6 +332,42 @@ module ActiveSupport
       since(-other)
     end
 
+    # Returns a new +ActiveSupport::TimeWithZone+ where one or more of the elements have
+    # been changed according to the +options+ parameter. The time options (<tt>:hour</tt>,
+    # <tt>:min</tt>, <tt>:sec</tt>, <tt>:usec</tt>, <tt>:nsec</tt>) reset cascadingly,
+    # so if only the hour is passed, then minute, sec, usec and nsec is set to 0. If the
+    # hour and minute is passed, then sec, usec and nsec is set to 0. The +options+
+    # parameter takes a hash with any of these keys: <tt>:year</tt>, <tt>:month</tt>,
+    # <tt>:day</tt>, <tt>:hour</tt>, <tt>:min</tt>, <tt>:sec</tt>, <tt>:usec</tt>,
+    # <tt>:nsec</tt>, <tt>:offset</tt>, <tt>:zone</tt>. Pass either <tt>:usec</tt>
+    # or <tt>:nsec</tt>, not both. Similarly, pass either <tt>:zone</tt> or
+    # <tt>:offset</tt>, not both.
+    #
+    #   t = Time.zone.now          # => Fri, 14 Apr 2017 11:45:15 EST -05:00
+    #   t.change(year: 2020)       # => Tue, 14 Apr 2020 11:45:15 EST -05:00
+    #   t.change(hour: 12)         # => Fri, 14 Apr 2017 12:00:00 EST -05:00
+    #   t.change(min: 30)          # => Fri, 14 Apr 2017 11:30:00 EST -05:00
+    #   t.change(offset: "-10:00") # => Fri, 14 Apr 2017 11:45:15 HST -10:00
+    #   t.change(zone: "Hawaii")   # => Fri, 14 Apr 2017 11:45:15 HST -10:00
+    def change(options)
+      if options[:zone] && options[:offset]
+        raise ArgumentError, "Can't change both :offset and :zone at the same time: #{options.inspect}"
+      end
+
+      new_time = time.change(options)
+
+      if options[:zone]
+        new_zone = ::Time.find_zone(options[:zone])
+      elsif options[:offset]
+        new_zone = ::Time.find_zone(new_time.utc_offset)
+      end
+
+      new_zone ||= time_zone
+      periods = new_zone.periods_for_local(new_time)
+
+      self.class.new(nil, new_zone, new_time, periods.include?(period) ? period : nil)
+    end
+
     # Uses Date to provide precise Time calculations for years, months, and days
     # according to the proleptic Gregorian calendar. The result is returned as a
     # new TimeWithZone object.
@@ -407,7 +446,18 @@ module ActiveSupport
     #   Time.zone.now.to_datetime                         # => Tue, 18 Aug 2015 02:32:20 +0000
     #   Time.current.in_time_zone('Hawaii').to_datetime   # => Mon, 17 Aug 2015 16:32:20 -1000
     def to_datetime
-      utc.to_datetime.new_offset(Rational(utc_offset, 86_400))
+      @to_datetime ||= utc.to_datetime.new_offset(Rational(utc_offset, 86_400))
+    end
+
+    # Returns an instance of +Time+, either with the same UTC offset
+    # as +self+ or in the local system timezone depending on the setting
+    # of +ActiveSupport.to_time_preserves_timezone+.
+    def to_time
+      if preserve_timezone
+        @to_time_with_instance_offset ||= getlocal(utc_offset)
+      else
+        @to_time_with_system_offset ||= getlocal
+      end
     end
 
     # So that +self+ <tt>acts_like?(:time)</tt>.
@@ -427,7 +477,8 @@ module ActiveSupport
     end
 
     def freeze
-      period; utc; time # preload instance variables before freezing
+      # preload instance variables before freezing
+      period; utc; time; to_datetime; to_time
       super
     end
 
@@ -459,7 +510,7 @@ module ActiveSupport
     def method_missing(sym, *args, &block)
       wrap_with_time_zone time.__send__(sym, *args, &block)
     rescue NoMethodError => e
-      raise e, e.message.sub(time.inspect, self.inspect), e.backtrace
+      raise e, e.message.sub(time.inspect, inspect), e.backtrace
     end
 
     private
@@ -477,11 +528,13 @@ module ActiveSupport
       end
 
       def transfer_time_values_to_utc_constructor(time)
+        # avoid creating another Time object if possible
+        return time if time.instance_of?(::Time) && time.utc?
         ::Time.utc(time.year, time.month, time.day, time.hour, time.min, time.sec + time.subsec)
       end
 
       def duration_of_variable_length?(obj)
-        ActiveSupport::Duration === obj && obj.parts.any? {|p| [:years, :months, :days].include?(p[0]) }
+        ActiveSupport::Duration === obj && obj.parts.any? { |p| [:years, :months, :weeks, :days].include?(p[0]) }
       end
 
       def wrap_with_time_zone(time)
diff --git a/activesupport/lib/active_support/values/time_zone.rb b/activesupport/lib/active_support/values/time_zone.rb
index 19420cee5e..4d81ac939e 100644
--- a/activesupport/lib/active_support/values/time_zone.rb
+++ b/activesupport/lib/active_support/values/time_zone.rb
@@ -1,12 +1,14 @@
-require 'tzinfo'
-require 'concurrent/map'
-require 'active_support/core_ext/object/blank'
+# frozen_string_literal: true
+
+require "tzinfo"
+require "concurrent/map"
+require "active_support/core_ext/object/blank"
 
 module ActiveSupport
   # The TimeZone class serves as a wrapper around TZInfo::Timezone instances.
   # It allows us to do the following:
   #
-  # * Limit the set of zones provided by TZInfo to a meaningful subset of 146
+  # * Limit the set of zones provided by TZInfo to a meaningful subset of 134
   #   zones.
   # * Retrieve and display zones with a friendlier name
   #   (e.g., "Eastern Time (US & Canada)" instead of "America/New_York").
@@ -28,7 +30,7 @@ module ActiveSupport
   class TimeZone
     # Keys are Rails TimeZone names, values are TZInfo identifiers.
     MAPPING = {
-      "International Date Line West" => "Pacific/Midway",
+      "International Date Line West" => "Etc/GMT+12",
       "Midway Island"                => "Pacific/Midway",
       "American Samoa"               => "Pacific/Pago_Pago",
       "Hawaii"                       => "Pacific/Honolulu",
@@ -59,6 +61,7 @@ module ActiveSupport
       "Buenos Aires"                 => "America/Argentina/Buenos_Aires",
       "Montevideo"                   => "America/Montevideo",
       "Georgetown"                   => "America/Guyana",
+      "Puerto Rico"                  => "America/Puerto_Rico",
       "Greenland"                    => "America/Godthab",
       "Mid-Atlantic"                 => "Atlantic/South_Georgia",
       "Azores"                       => "Atlantic/Azores",
@@ -180,8 +183,8 @@ module ActiveSupport
       "Samoa"                        => "Pacific/Apia"
     }
 
-    UTC_OFFSET_WITH_COLON = '%s%02d:%02d'
-    UTC_OFFSET_WITHOUT_COLON = UTC_OFFSET_WITH_COLON.tr(':', '')
+    UTC_OFFSET_WITH_COLON = "%s%02d:%02d"
+    UTC_OFFSET_WITHOUT_COLON = UTC_OFFSET_WITH_COLON.tr(":", "")
 
     @lazy_zones_map = Concurrent::Map.new
     @country_zones  = Concurrent::Map.new
@@ -193,7 +196,7 @@ module ActiveSupport
       #   ActiveSupport::TimeZone.seconds_to_utc_offset(-21_600) # => "-06:00"
       def seconds_to_utc_offset(seconds, colon = true)
         format = colon ? UTC_OFFSET_WITH_COLON : UTC_OFFSET_WITHOUT_COLON
-        sign = (seconds < 0 ? '-' : '+')
+        sign = (seconds < 0 ? "-" : "+")
         hours = seconds.abs / 3600
         minutes = (seconds.abs % 3600) / 60
         format % [sign, hours, minutes]
@@ -226,17 +229,17 @@ module ActiveSupport
       # Returns +nil+ if no such time zone is known to the system.
       def [](arg)
         case arg
-          when String
+        when String
           begin
             @lazy_zones_map[arg] ||= create(arg)
           rescue TZInfo::InvalidTimezoneIdentifier
             nil
           end
-          when Numeric, ActiveSupport::Duration
-            arg *= 3600 if arg.abs <= 13
-            all.find { |z| z.utc_offset == arg.to_i }
+        when Numeric, ActiveSupport::Duration
+          arg *= 3600 if arg.abs <= 13
+          all.find { |z| z.utc_offset == arg.to_i }
           else
-            raise ArgumentError, "invalid argument to TimeZone[]: #{arg.inspect}"
+          raise ArgumentError, "invalid argument to TimeZone[]: #{arg.inspect}"
         end
       end
 
@@ -250,18 +253,31 @@ module ActiveSupport
       # for time zones in the country specified by its ISO 3166-1 Alpha2 code.
       def country_zones(country_code)
         code = country_code.to_s.upcase
-        @country_zones[code] ||=
-          TZInfo::Country.get(code).zone_identifiers.map do |tz_id|
-            name = MAPPING.key(tz_id)
-            name && self[name]
-          end.compact.sort!
+        @country_zones[code] ||= load_country_zones(code)
+      end
+
+      def clear #:nodoc:
+        @lazy_zones_map = Concurrent::Map.new
+        @country_zones  = Concurrent::Map.new
+        @zones = nil
+        @zones_map = nil
       end
 
       private
+        def load_country_zones(code)
+          country = TZInfo::Country.get(code)
+          country.zone_identifiers.map do |tz_id|
+            if MAPPING.value?(tz_id)
+              self[MAPPING.key(tz_id)]
+            else
+              create(tz_id, nil, TZInfo::Timezone.new(tz_id))
+            end
+          end.sort!
+        end
+
         def zones_map
-          @zones_map ||= begin
-            MAPPING.each_key {|place| self[place]} # load all the zones
-            @lazy_zones_map
+          @zones_map ||= MAPPING.each_with_object({}) do |(name, _), zones|
+            zones[name] = self[name]
           end
         end
     end
@@ -295,7 +311,7 @@ module ActiveSupport
     #   zone = ActiveSupport::TimeZone['Central Time (US & Canada)']
     #   zone.formatted_offset        # => "-06:00"
     #   zone.formatted_offset(false) # => "-0600"
-    def formatted_offset(colon=true, alternate_utc_string = nil)
+    def formatted_offset(colon = true, alternate_utc_string = nil)
       utc_offset == 0 && alternate_utc_string || self.class.seconds_to_utc_offset(utc_offset, colon)
     end
 
@@ -340,6 +356,41 @@ module ActiveSupport
     end
 
     # Method for creating new ActiveSupport::TimeWithZone instance in time zone
+    # of +self+ from an ISO 8601 string.
+    #
+    #   Time.zone = 'Hawaii'                     # => "Hawaii"
+    #   Time.zone.iso8601('1999-12-31T14:00:00') # => Fri, 31 Dec 1999 14:00:00 HST -10:00
+    #
+    # If the time components are missing then they will be set to zero.
+    #
+    #   Time.zone = 'Hawaii'            # => "Hawaii"
+    #   Time.zone.iso8601('1999-12-31') # => Fri, 31 Dec 1999 00:00:00 HST -10:00
+    #
+    # If the string is invalid then an +ArgumentError+ will be raised unlike +parse+
+    # which usually returns +nil+ when given an invalid date string.
+    def iso8601(str)
+      parts = Date._iso8601(str)
+
+      raise ArgumentError, "invalid date" if parts.empty?
+
+      time = Time.new(
+        parts.fetch(:year),
+        parts.fetch(:mon),
+        parts.fetch(:mday),
+        parts.fetch(:hour, 0),
+        parts.fetch(:min, 0),
+        parts.fetch(:sec, 0) + parts.fetch(:sec_fraction, 0),
+        parts.fetch(:offset, 0)
+      )
+
+      if parts[:offset]
+        TimeWithZone.new(time.utc, self)
+      else
+        TimeWithZone.new(nil, self, time)
+      end
+    end
+
+    # Method for creating new ActiveSupport::TimeWithZone instance in time zone
     # of +self+ from parsed string.
     #
     #   Time.zone = 'Hawaii'                   # => "Hawaii"
@@ -355,10 +406,42 @@ module ActiveSupport
     # components are supplied, then the day of the month defaults to 1:
     #
     #   Time.zone.parse('Mar 2000') # => Wed, 01 Mar 2000 00:00:00 HST -10:00
-    def parse(str, now=now())
+    #
+    # If the string is invalid then an +ArgumentError+ could be raised.
+    def parse(str, now = now())
       parts_to_time(Date._parse(str, false), now)
     end
 
+    # Method for creating new ActiveSupport::TimeWithZone instance in time zone
+    # of +self+ from an RFC 3339 string.
+    #
+    #   Time.zone = 'Hawaii'                     # => "Hawaii"
+    #   Time.zone.rfc3339('2000-01-01T00:00:00Z') # => Fri, 31 Dec 1999 14:00:00 HST -10:00
+    #
+    # If the time or zone components are missing then an +ArgumentError+ will
+    # be raised. This is much stricter than either +parse+ or +iso8601+ which
+    # allow for missing components.
+    #
+    #   Time.zone = 'Hawaii'            # => "Hawaii"
+    #   Time.zone.rfc3339('1999-12-31') # => ArgumentError: invalid date
+    def rfc3339(str)
+      parts = Date._rfc3339(str)
+
+      raise ArgumentError, "invalid date" if parts.empty?
+
+      time = Time.new(
+        parts.fetch(:year),
+        parts.fetch(:mon),
+        parts.fetch(:mday),
+        parts.fetch(:hour),
+        parts.fetch(:min),
+        parts.fetch(:sec) + parts.fetch(:sec_fraction, 0),
+        parts.fetch(:offset)
+      )
+
+      TimeWithZone.new(time.utc, self)
+    end
+
     # Parses +str+ according to +format+ and returns an ActiveSupport::TimeWithZone.
     #
     # Assumes that +str+ is a time in the time zone +self+,
@@ -379,7 +462,7 @@ module ActiveSupport
     # components are supplied, then the day of the month defaults to 1:
     #
     #   Time.zone.strptime('Mar 2000', '%b %Y') # => Wed, 01 Mar 2000 00:00:00 HST -10:00
-    def strptime(str, format, now=now())
+    def strptime(str, format, now = now())
       parts_to_time(DateTime._strptime(str, format), now)
     end
 
@@ -416,7 +499,7 @@ module ActiveSupport
 
     # Adjust the given time to the simultaneous time in UTC. Returns a
     # Time.utc() instance.
-    def local_to_utc(time, dst=true)
+    def local_to_utc(time, dst = true)
       tzinfo.local_to_utc(time, dst)
     end
 
@@ -428,8 +511,8 @@ module ActiveSupport
 
     # Available so that TimeZone instances respond like TZInfo::Timezone
     # instances.
-    def period_for_local(time, dst=true)
-      tzinfo.period_for_local(time, dst)
+    def period_for_local(time, dst = true)
+      tzinfo.period_for_local(time, dst) { |periods| periods.last }
     end
 
     def periods_for_local(time) #:nodoc:
@@ -437,29 +520,34 @@ module ActiveSupport
     end
 
     def init_with(coder) #:nodoc:
-      initialize(coder['name'])
+      initialize(coder["name"])
     end
 
     def encode_with(coder) #:nodoc:
-      coder.tag ="!ruby/object:#{self.class}"
-      coder.map = { 'name' => tzinfo.name }
+      coder.tag = "!ruby/object:#{self.class}"
+      coder.map = { "name" => tzinfo.name }
     end
 
     private
       def parts_to_time(parts, now)
+        raise ArgumentError, "invalid date" if parts.nil?
         return if parts.empty?
 
-        time = Time.new(
-          parts.fetch(:year, now.year),
-          parts.fetch(:mon, now.month),
-          parts.fetch(:mday, parts[:year] || parts[:mon] ? 1 : now.day),
-          parts.fetch(:hour, 0),
-          parts.fetch(:min, 0),
-          parts.fetch(:sec, 0) + parts.fetch(:sec_fraction, 0),
-          parts.fetch(:offset, 0)
-        )
-
-        if parts[:offset]
+        if parts[:seconds]
+          time = Time.at(parts[:seconds])
+        else
+          time = Time.new(
+            parts.fetch(:year, now.year),
+            parts.fetch(:mon, now.month),
+            parts.fetch(:mday, parts[:year] || parts[:mon] ? 1 : now.day),
+            parts.fetch(:hour, 0),
+            parts.fetch(:min, 0),
+            parts.fetch(:sec, 0) + parts.fetch(:sec_fraction, 0),
+            parts.fetch(:offset, 0)
+          )
+        end
+
+        if parts[:offset] || parts[:seconds]
           TimeWithZone.new(time.utc, self)
         else
           TimeWithZone.new(nil, self, time)
diff --git a/activesupport/lib/active_support/values/unicode_tables.dat b/activesupport/lib/active_support/values/unicode_tables.dat
index dd2c178fb6..f7d9c48bbe 100644
--- a/activesupport/lib/active_support/values/unicode_tables.dat
+++ b/activesupport/lib/active_support/values/unicode_tables.dat
diff --git a/activesupport/lib/active_support/version.rb b/activesupport/lib/active_support/version.rb
index fe03984546..928838c837 100644
--- a/activesupport/lib/active_support/version.rb
+++ b/activesupport/lib/active_support/version.rb
@@ -1,4 +1,6 @@
-require_relative 'gem_version'
+# frozen_string_literal: true
+
+require_relative "gem_version"
 
 module ActiveSupport
   # Returns the version of the currently loaded ActiveSupport as a <tt>Gem::Version</tt>
diff --git a/activesupport/lib/active_support/xml_mini.rb b/activesupport/lib/active_support/xml_mini.rb
index 99fc26549e..ee2048cb54 100644
--- a/activesupport/lib/active_support/xml_mini.rb
+++ b/activesupport/lib/active_support/xml_mini.rb
@@ -1,9 +1,11 @@
-require 'time'
-require 'base64'
-require 'bigdecimal'
-require 'active_support/core_ext/module/delegation'
-require 'active_support/core_ext/string/inflections'
-require 'active_support/core_ext/date_time/calculations'
+# frozen_string_literal: true
+
+require "time"
+require "base64"
+require "bigdecimal"
+require "active_support/core_ext/module/delegation"
+require "active_support/core_ext/string/inflections"
+require "active_support/core_ext/date_time/calculations"
 
 module ActiveSupport
   # = XmlMini
@@ -20,11 +22,11 @@ module ActiveSupport
       attr_writer :original_filename, :content_type
 
       def original_filename
-        @original_filename || 'untitled'
+        @original_filename || "untitled"
       end
 
       def content_type
-        @content_type || 'application/octet-stream'
+        @content_type || "application/octet-stream"
       end
     end
 
@@ -48,8 +50,8 @@ module ActiveSupport
       }
 
       # No need to map these on Ruby 2.4+
-      TYPE_NAMES["Fixnum"] = "integer" unless Fixnum == Integer
-      TYPE_NAMES["Bignum"] = "integer" unless Bignum == Integer
+      TYPE_NAMES["Fixnum"] = "integer" unless 0.class == Integer
+      TYPE_NAMES["Bignum"] = "integer" unless 0.class == Integer
     end
 
     FORMATTING = {
@@ -68,7 +70,17 @@ module ActiveSupport
         "datetime"     => Proc.new { |time|    Time.xmlschema(time).utc rescue ::DateTime.parse(time).utc },
         "integer"      => Proc.new { |integer| integer.to_i },
         "float"        => Proc.new { |float|   float.to_f },
-        "decimal"      => Proc.new { |number|  BigDecimal(number) },
+        "decimal"      => Proc.new do |number|
+          if String === number
+            begin
+              BigDecimal(number)
+            rescue ArgumentError
+              BigDecimal("0")
+            end
+          else
+            BigDecimal(number)
+          end
+        end,
         "boolean"      => Proc.new { |boolean| %w(1 true).include?(boolean.to_s.strip) },
         "string"       => Proc.new { |string|  string.to_s },
         "yaml"         => Proc.new { |yaml|    YAML::load(yaml) rescue yaml },
@@ -86,7 +98,7 @@ module ActiveSupport
     attr_accessor :depth
     self.depth = 100
 
-    delegate :parse, :to => :backend
+    delegate :parse, to: :backend
 
     def backend
       current_thread_backend || @backend
@@ -108,7 +120,7 @@ module ActiveSupport
 
     def to_tag(key, value, options)
       type_name = options.delete(:type)
-      merged_options = options.merge(:root => key, :skip_instruct => true)
+      merged_options = options.merge(root: key, skip_instruct: true)
 
       if value.is_a?(::Method) || value.is_a?(::Proc)
         if value.arity == 1
@@ -126,7 +138,7 @@ module ActiveSupport
 
         key = rename_key(key.to_s, options)
 
-        attributes = options[:skip_types] || type_name.nil? ? { } : { :type => type_name }
+        attributes = options[:skip_types] || type_name.nil? ? {} : { type: type_name }
         attributes[:nil] = true if value.nil?
 
         encoding = options[:encoding] || DEFAULT_ENCODINGS[type_name]
@@ -149,33 +161,31 @@ module ActiveSupport
       key
     end
 
-    protected
-
-    def _dasherize(key)
-      # $2 must be a non-greedy regex for this to work
-      left, middle, right = /\A(_*)(.*?)(_*)\Z/.match(key.strip)[1,3]
-      "#{left}#{middle.tr('_ ', '--')}#{right}"
-    end
+    private
 
-    # TODO: Add support for other encodings
-    def _parse_binary(bin, entity) #:nodoc:
-      case entity['encoding']
-      when 'base64'
-        ::Base64.decode64(bin)
-      else
-        bin
+      def _dasherize(key)
+        # $2 must be a non-greedy regex for this to work
+        left, middle, right = /\A(_*)(.*?)(_*)\Z/.match(key.strip)[1, 3]
+        "#{left}#{middle.tr('_ ', '--')}#{right}"
       end
-    end
 
-    def _parse_file(file, entity)
-      f = StringIO.new(::Base64.decode64(file))
-      f.extend(FileLike)
-      f.original_filename = entity['name']
-      f.content_type = entity['content_type']
-      f
-    end
+      # TODO: Add support for other encodings
+      def _parse_binary(bin, entity)
+        case entity["encoding"]
+        when "base64"
+          ::Base64.decode64(bin)
+        else
+          bin
+        end
+      end
 
-    private
+      def _parse_file(file, entity)
+        f = StringIO.new(::Base64.decode64(file))
+        f.extend(FileLike)
+        f.original_filename = entity["name"]
+        f.content_type = entity["content_type"]
+        f
+      end
 
       def current_thread_backend
         Thread.current[:xml_mini_backend]
@@ -195,5 +205,5 @@ module ActiveSupport
       end
   end
 
-  XmlMini.backend = 'REXML'
+  XmlMini.backend = "REXML"
 end
diff --git a/activesupport/lib/active_support/xml_mini/jdom.rb b/activesupport/lib/active_support/xml_mini/jdom.rb
index 94751bbc04..7f94a64016 100644
--- a/activesupport/lib/active_support/xml_mini/jdom.rb
+++ b/activesupport/lib/active_support/xml_mini/jdom.rb
@@ -1,9 +1,11 @@
-raise "JRuby is required to use the JDOM backend for XmlMini" unless RUBY_PLATFORM =~ /java/
+# frozen_string_literal: true
 
-require 'jruby'
+raise "JRuby is required to use the JDOM backend for XmlMini" unless RUBY_PLATFORM.include?("java")
+
+require "jruby"
 include Java
 
-require 'active_support/core_ext/object/blank'
+require "active_support/core_ext/object/blank"
 
 java_import javax.xml.parsers.DocumentBuilder unless defined? DocumentBuilder
 java_import javax.xml.parsers.DocumentBuilderFactory unless defined? DocumentBuilderFactory
@@ -16,7 +18,7 @@ module ActiveSupport
   module XmlMini_JDOM #:nodoc:
     extend self
 
-    CONTENT_KEY = '__content__'.freeze
+    CONTENT_KEY = "__content__".freeze
 
     NODE_TYPE_NAMES = %w{ATTRIBUTE_NODE CDATA_SECTION_NODE COMMENT_NODE DOCUMENT_FRAGMENT_NODE
     DOCUMENT_NODE DOCUMENT_TYPE_NODE ELEMENT_NODE ENTITY_NODE ENTITY_REFERENCE_NODE NOTATION_NODE
@@ -38,7 +40,7 @@ module ActiveSupport
       else
         @dbf = DocumentBuilderFactory.new_instance
         # secure processing of java xml
-        # http://www.ibm.com/developerworks/xml/library/x-tipcfsx/index.html
+        # https://archive.is/9xcQQ
         @dbf.setFeature("http://apache.org/xml/features/nonvalidating/load-external-dtd", false)
         @dbf.setFeature("http://xml.org/sax/features/external-general-entities", false)
         @dbf.setFeature("http://xml.org/sax/features/external-parameter-entities", false)
@@ -46,136 +48,136 @@ module ActiveSupport
         xml_string_reader = StringReader.new(data)
         xml_input_source = InputSource.new(xml_string_reader)
         doc = @dbf.new_document_builder.parse(xml_input_source)
-        merge_element!({CONTENT_KEY => ''}, doc.document_element, XmlMini.depth)
+        merge_element!({ CONTENT_KEY => "" }, doc.document_element, XmlMini.depth)
       end
     end
 
     private
 
-    # Convert an XML element and merge into the hash
-    #
-    # hash::
-    #   Hash to merge the converted element into.
-    # element::
-    #   XML element to merge into hash
-    def merge_element!(hash, element, depth)
-      raise 'Document too deep!' if depth == 0
-      delete_empty(hash)
-      merge!(hash, element.tag_name, collapse(element, depth))
-    end
-
-    def delete_empty(hash)
-      hash.delete(CONTENT_KEY) if hash[CONTENT_KEY] == ''
-    end
+      # Convert an XML element and merge into the hash
+      #
+      # hash::
+      #   Hash to merge the converted element into.
+      # element::
+      #   XML element to merge into hash
+      def merge_element!(hash, element, depth)
+        raise "Document too deep!" if depth == 0
+        delete_empty(hash)
+        merge!(hash, element.tag_name, collapse(element, depth))
+      end
 
-    # Actually converts an XML document element into a data structure.
-    #
-    # element::
-    #   The document element to be collapsed.
-    def collapse(element, depth)
-      hash = get_attributes(element)
+      def delete_empty(hash)
+        hash.delete(CONTENT_KEY) if hash[CONTENT_KEY] == ""
+      end
 
-      child_nodes = element.child_nodes
-      if child_nodes.length > 0
-        (0...child_nodes.length).each do |i|
-          child = child_nodes.item(i)
-          merge_element!(hash, child, depth - 1) unless child.node_type == Node.TEXT_NODE
+      # Actually converts an XML document element into a data structure.
+      #
+      # element::
+      #   The document element to be collapsed.
+      def collapse(element, depth)
+        hash = get_attributes(element)
+
+        child_nodes = element.child_nodes
+        if child_nodes.length > 0
+          (0...child_nodes.length).each do |i|
+            child = child_nodes.item(i)
+            merge_element!(hash, child, depth - 1) unless child.node_type == Node.TEXT_NODE
+          end
+          merge_texts!(hash, element) unless empty_content?(element)
+          hash
+        else
+          merge_texts!(hash, element)
         end
-        merge_texts!(hash, element) unless empty_content?(element)
-        hash
-      else
-        merge_texts!(hash, element)
       end
-    end
 
-    # Merge all the texts of an element into the hash
-    #
-    # hash::
-    #   Hash to add the converted element to.
-    # element::
-    #   XML element whose texts are to me merged into the hash
-    def merge_texts!(hash, element)
-      delete_empty(hash)
-      text_children = texts(element)
-      if text_children.join.empty?
-        hash
-      else
-        # must use value to prevent double-escaping
-        merge!(hash, CONTENT_KEY, text_children.join)
+      # Merge all the texts of an element into the hash
+      #
+      # hash::
+      #   Hash to add the converted element to.
+      # element::
+      #   XML element whose texts are to me merged into the hash
+      def merge_texts!(hash, element)
+        delete_empty(hash)
+        text_children = texts(element)
+        if text_children.join.empty?
+          hash
+        else
+          # must use value to prevent double-escaping
+          merge!(hash, CONTENT_KEY, text_children.join)
+        end
       end
-    end
 
-    # Adds a new key/value pair to an existing Hash. If the key to be added
-    # already exists and the existing value associated with key is not
-    # an Array, it will be wrapped in an Array. Then the new value is
-    # appended to that Array.
-    #
-    # hash::
-    #   Hash to add key/value pair to.
-    # key::
-    #   Key to be added.
-    # value::
-    #   Value to be associated with key.
-    def merge!(hash, key, value)
-      if hash.has_key?(key)
-        if hash[key].instance_of?(Array)
-          hash[key] << value
+      # Adds a new key/value pair to an existing Hash. If the key to be added
+      # already exists and the existing value associated with key is not
+      # an Array, it will be wrapped in an Array. Then the new value is
+      # appended to that Array.
+      #
+      # hash::
+      #   Hash to add key/value pair to.
+      # key::
+      #   Key to be added.
+      # value::
+      #   Value to be associated with key.
+      def merge!(hash, key, value)
+        if hash.has_key?(key)
+          if hash[key].instance_of?(Array)
+            hash[key] << value
+          else
+            hash[key] = [hash[key], value]
+          end
+        elsif value.instance_of?(Array)
+          hash[key] = [value]
         else
-          hash[key] = [hash[key], value]
+          hash[key] = value
         end
-      elsif value.instance_of?(Array)
-        hash[key] = [value]
-      else
-        hash[key] = value
+        hash
       end
-      hash
-    end
 
-    # Converts the attributes array of an XML element into a hash.
-    # Returns an empty Hash if node has no attributes.
-    #
-    # element::
-    #   XML element to extract attributes from.
-    def get_attributes(element)
-      attribute_hash = {}
-      attributes = element.attributes
-      (0...attributes.length).each do |i|
-         attribute_hash[CONTENT_KEY] ||= ''
-         attribute_hash[attributes.item(i).name] =  attributes.item(i).value
+      # Converts the attributes array of an XML element into a hash.
+      # Returns an empty Hash if node has no attributes.
+      #
+      # element::
+      #   XML element to extract attributes from.
+      def get_attributes(element)
+        attribute_hash = {}
+        attributes = element.attributes
+        (0...attributes.length).each do |i|
+          attribute_hash[CONTENT_KEY] ||= ""
+          attribute_hash[attributes.item(i).name] = attributes.item(i).value
+        end
+        attribute_hash
       end
-      attribute_hash
-    end
 
-    # Determines if a document element has text content
-    #
-    # element::
-    #   XML element to be checked.
-    def texts(element)
-      texts = []
-      child_nodes = element.child_nodes
-      (0...child_nodes.length).each do |i|
-        item = child_nodes.item(i)
-        if item.node_type == Node.TEXT_NODE
-          texts << item.get_data
+      # Determines if a document element has text content
+      #
+      # element::
+      #   XML element to be checked.
+      def texts(element)
+        texts = []
+        child_nodes = element.child_nodes
+        (0...child_nodes.length).each do |i|
+          item = child_nodes.item(i)
+          if item.node_type == Node.TEXT_NODE
+            texts << item.get_data
+          end
         end
+        texts
       end
-      texts
-    end
 
-    # Determines if a document element has text content
-    #
-    # element::
-    #   XML element to be checked.
-    def empty_content?(element)
-      text = ''
-      child_nodes = element.child_nodes
-      (0...child_nodes.length).each do |i|
-        item = child_nodes.item(i)
-        if item.node_type == Node.TEXT_NODE
-          text << item.get_data.strip
+      # Determines if a document element has text content
+      #
+      # element::
+      #   XML element to be checked.
+      def empty_content?(element)
+        text = "".dup
+        child_nodes = element.child_nodes
+        (0...child_nodes.length).each do |i|
+          item = child_nodes.item(i)
+          if item.node_type == Node.TEXT_NODE
+            text << item.get_data.strip
+          end
         end
+        text.strip.length == 0
       end
-      text.strip.length == 0
-    end
   end
 end
diff --git a/activesupport/lib/active_support/xml_mini/libxml.rb b/activesupport/lib/active_support/xml_mini/libxml.rb
index bb0ea9c582..0b000fea60 100644
--- a/activesupport/lib/active_support/xml_mini/libxml.rb
+++ b/activesupport/lib/active_support/xml_mini/libxml.rb
@@ -1,6 +1,8 @@
-require 'libxml'
-require 'active_support/core_ext/object/blank'
-require 'stringio'
+# frozen_string_literal: true
+
+require "libxml"
+require "active_support/core_ext/object/blank"
+require "stringio"
 
 module ActiveSupport
   module XmlMini_LibXML #:nodoc:
@@ -11,18 +13,15 @@ module ActiveSupport
     #   XML Document string or IO to parse
     def parse(data)
       if !data.respond_to?(:read)
-        data = StringIO.new(data || '')
+        data = StringIO.new(data || "")
       end
 
-      char = data.getc
-      if char.nil?
+      if data.eof?
         {}
       else
-        data.ungetc(char)
         LibXML::XML::Parser.io(data).parse.to_hash
       end
     end
-
   end
 end
 
@@ -35,20 +34,20 @@ module LibXML #:nodoc:
     end
 
     module Node #:nodoc:
-      CONTENT_ROOT = '__content__'.freeze
+      CONTENT_ROOT = "__content__".freeze
 
       # Convert XML document to hash.
       #
       # hash::
       #   Hash to merge the converted element into.
-      def to_hash(hash={})
+      def to_hash(hash = {})
         node_hash = {}
 
         # Insert node hash into parent hash correctly.
         case hash[name]
-          when Array then hash[name] << node_hash
-          when Hash  then hash[name] = [hash[name], node_hash]
-          when nil   then hash[name] = node_hash
+        when Array then hash[name] << node_hash
+        when Hash  then hash[name] = [hash[name], node_hash]
+        when nil   then hash[name] = node_hash
         end
 
         # Handle child elements
@@ -56,7 +55,7 @@ module LibXML #:nodoc:
           if c.element?
             c.to_hash(node_hash)
           elsif c.text? || c.cdata?
-            node_hash[CONTENT_ROOT] ||= ''
+            node_hash[CONTENT_ROOT] ||= "".dup
             node_hash[CONTENT_ROOT] << c.content
           end
         end
@@ -75,5 +74,7 @@ module LibXML #:nodoc:
   end
 end
 
+# :enddoc:
+
 LibXML::XML::Document.include(LibXML::Conversions::Document)
 LibXML::XML::Node.include(LibXML::Conversions::Node)
diff --git a/activesupport/lib/active_support/xml_mini/libxmlsax.rb b/activesupport/lib/active_support/xml_mini/libxmlsax.rb
index 70a95299ec..dcf16e6084 100644
--- a/activesupport/lib/active_support/xml_mini/libxmlsax.rb
+++ b/activesupport/lib/active_support/xml_mini/libxmlsax.rb
@@ -1,6 +1,8 @@
-require 'libxml'
-require 'active_support/core_ext/object/blank'
-require 'stringio'
+# frozen_string_literal: true
+
+require "libxml"
+require "active_support/core_ext/object/blank"
+require "stringio"
 
 module ActiveSupport
   module XmlMini_LibXMLSAX #:nodoc:
@@ -9,11 +11,10 @@ module ActiveSupport
     # Class that will build the hash while the XML document
     # is being parsed using SAX events.
     class HashBuilder
-
       include LibXML::XML::SaxParser::Callbacks
 
-      CONTENT_KEY   = '__content__'.freeze
-      HASH_SIZE_KEY = '__hash_size__'.freeze
+      CONTENT_KEY   = "__content__".freeze
+      HASH_SIZE_KEY = "__hash_size__".freeze
 
       attr_reader :hash
 
@@ -22,7 +23,7 @@ module ActiveSupport
       end
 
       def on_start_document
-        @hash = { CONTENT_KEY => '' }
+        @hash = { CONTENT_KEY => "".dup }
         @hash_stack = [@hash]
       end
 
@@ -32,20 +33,20 @@ module ActiveSupport
       end
 
       def on_start_element(name, attrs = {})
-        new_hash = { CONTENT_KEY => '' }.merge!(attrs)
+        new_hash = { CONTENT_KEY => "".dup }.merge!(attrs)
         new_hash[HASH_SIZE_KEY] = new_hash.size + 1
 
         case current_hash[name]
-          when Array then current_hash[name] << new_hash
-          when Hash  then current_hash[name] = [current_hash[name], new_hash]
-          when nil   then current_hash[name] = new_hash
+        when Array then current_hash[name] << new_hash
+        when Hash  then current_hash[name] = [current_hash[name], new_hash]
+        when nil   then current_hash[name] = new_hash
         end
 
         @hash_stack.push(new_hash)
       end
 
       def on_end_element(name)
-        if current_hash.length > current_hash.delete(HASH_SIZE_KEY) && current_hash[CONTENT_KEY].blank? || current_hash[CONTENT_KEY] == ''
+        if current_hash.length > current_hash.delete(HASH_SIZE_KEY) && current_hash[CONTENT_KEY].blank? || current_hash[CONTENT_KEY] == ""
           current_hash.delete(CONTENT_KEY)
         end
         @hash_stack.pop
@@ -63,18 +64,15 @@ module ActiveSupport
 
     def parse(data)
       if !data.respond_to?(:read)
-        data = StringIO.new(data || '')
+        data = StringIO.new(data || "")
       end
 
-      char = data.getc
-      if char.nil?
+      if data.eof?
         {}
       else
-        data.ungetc(char)
-
         LibXML::XML::Error.set_handler(&LibXML::XML::Error::QUIET_HANDLER)
         parser = LibXML::XML::SaxParser.io(data)
-        document = self.document_class.new
+        document = document_class.new
 
         parser.callbacks = document
         parser.parse
diff --git a/activesupport/lib/active_support/xml_mini/nokogiri.rb b/activesupport/lib/active_support/xml_mini/nokogiri.rb
index 619cc7522d..5ee6fc8159 100644
--- a/activesupport/lib/active_support/xml_mini/nokogiri.rb
+++ b/activesupport/lib/active_support/xml_mini/nokogiri.rb
@@ -1,11 +1,13 @@
+# frozen_string_literal: true
+
 begin
-  require 'nokogiri'
+  require "nokogiri"
 rescue LoadError => e
   $stderr.puts "You don't have nokogiri installed in your application. Please add it to your Gemfile and run bundle install"
   raise e
 end
-require 'active_support/core_ext/object/blank'
-require 'stringio'
+require "active_support/core_ext/object/blank"
+require "stringio"
 
 module ActiveSupport
   module XmlMini_Nokogiri #:nodoc:
@@ -16,14 +18,12 @@ module ActiveSupport
     #   XML Document string or IO to parse
     def parse(data)
       if !data.respond_to?(:read)
-        data = StringIO.new(data || '')
+        data = StringIO.new(data || "")
       end
 
-      char = data.getc
-      if char.nil?
+      if data.eof?
         {}
       else
-        data.ungetc(char)
         doc = Nokogiri::XML(data)
         raise doc.errors.first if doc.errors.length > 0
         doc.to_hash
@@ -38,20 +38,20 @@ module ActiveSupport
       end
 
       module Node #:nodoc:
-        CONTENT_ROOT = '__content__'.freeze
+        CONTENT_ROOT = "__content__".freeze
 
         # Convert XML document to hash.
         #
         # hash::
         #   Hash to merge the converted element into.
-        def to_hash(hash={})
+        def to_hash(hash = {})
           node_hash = {}
 
           # Insert node hash into parent hash correctly.
           case hash[name]
-            when Array then hash[name] << node_hash
-            when Hash  then hash[name] = [hash[name], node_hash]
-            when nil   then hash[name] = node_hash
+          when Array then hash[name] << node_hash
+          when Hash  then hash[name] = [hash[name], node_hash]
+          when nil   then hash[name] = node_hash
           end
 
           # Handle child elements
@@ -59,7 +59,7 @@ module ActiveSupport
             if c.element?
               c.to_hash(node_hash)
             elsif c.text? || c.cdata?
-              node_hash[CONTENT_ROOT] ||= ''
+              node_hash[CONTENT_ROOT] ||= "".dup
               node_hash[CONTENT_ROOT] << c.content
             end
           end
diff --git a/activesupport/lib/active_support/xml_mini/nokogirisax.rb b/activesupport/lib/active_support/xml_mini/nokogirisax.rb
index be2d6a4cb1..b01ed00a14 100644
--- a/activesupport/lib/active_support/xml_mini/nokogirisax.rb
+++ b/activesupport/lib/active_support/xml_mini/nokogirisax.rb
@@ -1,11 +1,13 @@
+# frozen_string_literal: true
+
 begin
-  require 'nokogiri'
+  require "nokogiri"
 rescue LoadError => e
   $stderr.puts "You don't have nokogiri installed in your application. Please add it to your Gemfile and run bundle install"
   raise e
 end
-require 'active_support/core_ext/object/blank'
-require 'stringio'
+require "active_support/core_ext/object/blank"
+require "stringio"
 
 module ActiveSupport
   module XmlMini_NokogiriSAX #:nodoc:
@@ -14,9 +16,8 @@ module ActiveSupport
     # Class that will build the hash while the XML document
     # is being parsed using SAX events.
     class HashBuilder < Nokogiri::XML::SAX::Document
-
-      CONTENT_KEY   = '__content__'.freeze
-      HASH_SIZE_KEY = '__hash_size__'.freeze
+      CONTENT_KEY   = "__content__".freeze
+      HASH_SIZE_KEY = "__hash_size__".freeze
 
       attr_reader :hash
 
@@ -38,20 +39,20 @@ module ActiveSupport
       end
 
       def start_element(name, attrs = [])
-        new_hash = { CONTENT_KEY => '' }.merge!(Hash[attrs])
+        new_hash = { CONTENT_KEY => "".dup }.merge!(Hash[attrs])
         new_hash[HASH_SIZE_KEY] = new_hash.size + 1
 
         case current_hash[name]
-          when Array then current_hash[name] << new_hash
-          when Hash  then current_hash[name] = [current_hash[name], new_hash]
-          when nil   then current_hash[name] = new_hash
+        when Array then current_hash[name] << new_hash
+        when Hash  then current_hash[name] = [current_hash[name], new_hash]
+        when nil   then current_hash[name] = new_hash
         end
 
         @hash_stack.push(new_hash)
       end
 
       def end_element(name)
-        if current_hash.length > current_hash.delete(HASH_SIZE_KEY) && current_hash[CONTENT_KEY].blank? || current_hash[CONTENT_KEY] == ''
+        if current_hash.length > current_hash.delete(HASH_SIZE_KEY) && current_hash[CONTENT_KEY].blank? || current_hash[CONTENT_KEY] == ""
           current_hash.delete(CONTENT_KEY)
         end
         @hash_stack.pop
@@ -69,15 +70,13 @@ module ActiveSupport
 
     def parse(data)
       if !data.respond_to?(:read)
-        data = StringIO.new(data || '')
+        data = StringIO.new(data || "")
       end
 
-      char = data.getc
-      if char.nil?
+      if data.eof?
         {}
       else
-        data.ungetc(char)
-        document = self.document_class.new
+        document = document_class.new
         parser = Nokogiri::XML::SAX::Parser.new(document)
         parser.parse(data)
         document.hash
diff --git a/activesupport/lib/active_support/xml_mini/rexml.rb b/activesupport/lib/active_support/xml_mini/rexml.rb
index 95af5af2c0..32458d5b0d 100644
--- a/activesupport/lib/active_support/xml_mini/rexml.rb
+++ b/activesupport/lib/active_support/xml_mini/rexml.rb
@@ -1,12 +1,14 @@
-require 'active_support/core_ext/kernel/reporting'
-require 'active_support/core_ext/object/blank'
-require 'stringio'
+# frozen_string_literal: true
+
+require "active_support/core_ext/kernel/reporting"
+require "active_support/core_ext/object/blank"
+require "stringio"
 
 module ActiveSupport
   module XmlMini_REXML #:nodoc:
     extend self
 
-    CONTENT_KEY = '__content__'.freeze
+    CONTENT_KEY = "__content__".freeze
 
     # Parse an XML Document string or IO into a simple hash.
     #
@@ -17,13 +19,13 @@ module ActiveSupport
     #   XML Document string or IO to parse
     def parse(data)
       if !data.respond_to?(:read)
-        data = StringIO.new(data || '')
+        data = StringIO.new(data || "")
       end
 
       if data.eof?
         {}
       else
-        silence_warnings { require 'rexml/document' } unless defined?(REXML::Document)
+        silence_warnings { require "rexml/document" } unless defined?(REXML::Document)
         doc = REXML::Document.new(data)
 
         if doc.root
@@ -55,7 +57,7 @@ module ActiveSupport
         hash = get_attributes(element)
 
         if element.has_elements?
-          element.each_element {|child| merge_element!(hash, child, depth - 1) }
+          element.each_element { |child| merge_element!(hash, child, depth - 1) }
           merge_texts!(hash, element) unless empty_content?(element)
           hash
         else
@@ -74,7 +76,7 @@ module ActiveSupport
           hash
         else
           # must use value to prevent double-escaping
-          texts = ''
+          texts = "".dup
           element.texts.each { |t| texts << t.value }
           merge!(hash, CONTENT_KEY, texts)
         end
@@ -113,7 +115,7 @@ module ActiveSupport
       #   XML element to extract attributes from.
       def get_attributes(element)
         attributes = {}
-        element.attributes.each { |n,v| attributes[n] = v }
+        element.attributes.each { |n, v| attributes[n] = v }
         attributes
       end
 
diff --git a/activesupport/test/abstract_unit.rb b/activesupport/test/abstract_unit.rb
index bab7440397..f214898145 100644
--- a/activesupport/test/abstract_unit.rb
+++ b/activesupport/test/abstract_unit.rb
@@ -1,17 +1,19 @@
+# frozen_string_literal: true
+
 ORIG_ARGV = ARGV.dup
 
-require 'active_support/core_ext/kernel/reporting'
+require "active_support/core_ext/kernel/reporting"
 
 silence_warnings do
-  Encoding.default_internal = "UTF-8"
-  Encoding.default_external = "UTF-8"
+  Encoding.default_internal = Encoding::UTF_8
+  Encoding.default_external = Encoding::UTF_8
 end
 
-require 'active_support/testing/autorun'
-require 'active_support/testing/method_call_assertions'
+require "active_support/testing/autorun"
+require "active_support/testing/method_call_assertions"
 
-ENV['NO_RELOAD'] = '1'
-require 'active_support'
+ENV["NO_RELOAD"] = "1"
+require "active_support"
 
 Thread.abort_on_exception = true
 
@@ -19,21 +21,25 @@ Thread.abort_on_exception = true
 ActiveSupport::Deprecation.debug = true
 
 # Default to old to_time behavior but allow running tests with new behavior
-ActiveSupport.to_time_preserves_timezone = ENV['PRESERVE_TIMEZONES'] == '1'
+ActiveSupport.to_time_preserves_timezone = ENV["PRESERVE_TIMEZONES"] == "1"
 
 # Disable available locale checks to avoid warnings running the test suite.
 I18n.enforce_available_locales = false
 
-# Skips the current run on Rubinius using Minitest::Assertions#skip
-def rubinius_skip(message = '')
-  skip message if RUBY_ENGINE == 'rbx'
-end
-
-# Skips the current run on JRuby using Minitest::Assertions#skip
-def jruby_skip(message = '')
-  skip message if defined?(JRUBY_VERSION)
-end
-
 class ActiveSupport::TestCase
   include ActiveSupport::Testing::MethodCallAssertions
+
+  # Skips the current run on Rubinius using Minitest::Assertions#skip
+  private def rubinius_skip(message = "")
+    skip message if RUBY_ENGINE == "rbx"
+  end
+
+  # Skips the current run on JRuby using Minitest::Assertions#skip
+  private def jruby_skip(message = "")
+    skip message if defined?(JRUBY_VERSION)
+  end
+
+  def frozen_error_class
+    Object.const_defined?(:FrozenError) ? FrozenError : RuntimeError
+  end
 end
diff --git a/activesupport/test/array_inquirer_test.rb b/activesupport/test/array_inquirer_test.rb
index 263ab3802b..d5419b862d 100644
--- a/activesupport/test/array_inquirer_test.rb
+++ b/activesupport/test/array_inquirer_test.rb
@@ -1,9 +1,11 @@
-require 'abstract_unit'
-require 'active_support/core_ext/array'
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "active_support/core_ext/array"
 
 class ArrayInquirerTest < ActiveSupport::TestCase
   def setup
-    @array_inquirer = ActiveSupport::ArrayInquirer.new([:mobile, :tablet, 'api'])
+    @array_inquirer = ActiveSupport::ArrayInquirer.new([:mobile, :tablet, "api"])
   end
 
   def test_individual
@@ -19,7 +21,7 @@ class ArrayInquirerTest < ActiveSupport::TestCase
   end
 
   def test_any_string_symbol_mismatch
-    assert @array_inquirer.any?('mobile')
+    assert @array_inquirer.any?("mobile")
     assert @array_inquirer.any?(:api)
   end
 
@@ -33,9 +35,29 @@ class ArrayInquirerTest < ActiveSupport::TestCase
   end
 
   def test_inquiry
-    result = [:mobile, :tablet, 'api'].inquiry
+    result = [:mobile, :tablet, "api"].inquiry
 
     assert_instance_of ActiveSupport::ArrayInquirer, result
     assert_equal @array_inquirer, result
   end
+
+  def test_respond_to_fallback_to_array_respond_to
+    Array.class_eval do
+      def respond_to_missing?(name, include_private = false)
+        (name == :foo) || super
+      end
+    end
+    arr = ActiveSupport::ArrayInquirer.new([:x])
+
+    assert_respond_to arr, :can_you_hear_me?
+    assert_respond_to arr, :foo
+    assert_not_respond_to arr, :nope
+  ensure
+    Array.class_eval do
+      undef_method :respond_to_missing?
+      def respond_to_missing?(name, include_private = false)
+        super
+      end
+    end
+  end
 end
diff --git a/activesupport/test/autoload_test.rb b/activesupport/test/autoload_test.rb
index c18b007612..216b069420 100644
--- a/activesupport/test/autoload_test.rb
+++ b/activesupport/test/autoload_test.rb
@@ -1,4 +1,6 @@
-require 'abstract_unit'
+# frozen_string_literal: true
+
+require "abstract_unit"
 
 class TestAutoloadModule < ActiveSupport::TestCase
   include ActiveSupport::Testing::Isolation
@@ -31,7 +33,7 @@ class TestAutoloadModule < ActiveSupport::TestCase
       end
     end
 
-    assert !$LOADED_FEATURES.include?(@some_class_path)
+    assert_not_includes $LOADED_FEATURES, @some_class_path
     assert_nothing_raised { ::Fixtures::Autoload::SomeClass }
   end
 
@@ -40,7 +42,7 @@ class TestAutoloadModule < ActiveSupport::TestCase
       autoload :SomeClass
     end
 
-    assert !$LOADED_FEATURES.include?(@some_class_path)
+    assert_not_includes $LOADED_FEATURES, @some_class_path
     assert_nothing_raised { ::Fixtures::Autoload::SomeClass }
   end
 
@@ -51,9 +53,9 @@ class TestAutoloadModule < ActiveSupport::TestCase
       end
     end
 
-    assert !$LOADED_FEATURES.include?(@some_class_path)
+    assert_not_includes $LOADED_FEATURES, @some_class_path
     ::Fixtures::Autoload.eager_load!
-    assert $LOADED_FEATURES.include?(@some_class_path)
+    assert_includes $LOADED_FEATURES, @some_class_path
     assert_nothing_raised { ::Fixtures::Autoload::SomeClass }
   end
 
@@ -64,7 +66,7 @@ class TestAutoloadModule < ActiveSupport::TestCase
       end
     end
 
-    assert !$LOADED_FEATURES.include?(@another_class_path)
+    assert_not_includes $LOADED_FEATURES, @another_class_path
     assert_nothing_raised { ::Fixtures::AnotherClass }
   end
 
@@ -75,7 +77,7 @@ class TestAutoloadModule < ActiveSupport::TestCase
       end
     end
 
-    assert !$LOADED_FEATURES.include?(@another_class_path)
+    assert_not_includes $LOADED_FEATURES, @another_class_path
     assert_nothing_raised { ::Fixtures::AnotherClass }
   end
-end
\ No newline at end of file
+end
diff --git a/activesupport/test/autoloading_fixtures/a/b.rb b/activesupport/test/autoloading_fixtures/a/b.rb
index 9c9e6454cf..27baaea08c 100644
--- a/activesupport/test/autoloading_fixtures/a/b.rb
+++ b/activesupport/test/autoloading_fixtures/a/b.rb
@@ -1,2 +1,4 @@
+# frozen_string_literal: true
+
 class A::B
-end
\ No newline at end of file
+end
diff --git a/activesupport/test/autoloading_fixtures/a/c/d.rb b/activesupport/test/autoloading_fixtures/a/c/d.rb
index 0f40d6fbc4..f07128673f 100644
--- a/activesupport/test/autoloading_fixtures/a/c/d.rb
+++ b/activesupport/test/autoloading_fixtures/a/c/d.rb
@@ -1,2 +1,4 @@
+# frozen_string_literal: true
+
 class A::C::D
-end
\ No newline at end of file
+end
diff --git a/activesupport/test/autoloading_fixtures/a/c/em/f.rb b/activesupport/test/autoloading_fixtures/a/c/em/f.rb
index 8b28e19148..78c96cf45f 100644
--- a/activesupport/test/autoloading_fixtures/a/c/em/f.rb
+++ b/activesupport/test/autoloading_fixtures/a/c/em/f.rb
@@ -1,2 +1,4 @@
+# frozen_string_literal: true
+
 class A::C::EM::F
-end
\ No newline at end of file
+end
diff --git a/activesupport/test/autoloading_fixtures/application.rb b/activesupport/test/autoloading_fixtures/application.rb
index d7d3096dcb..971cbe1b17 100644
--- a/activesupport/test/autoloading_fixtures/application.rb
+++ b/activesupport/test/autoloading_fixtures/application.rb
@@ -1 +1,3 @@
+# frozen_string_literal: true
+
 ApplicationController = 10
diff --git a/activesupport/test/autoloading_fixtures/circular1.rb b/activesupport/test/autoloading_fixtures/circular1.rb
index a45761f066..7f891b5eb1 100644
--- a/activesupport/test/autoloading_fixtures/circular1.rb
+++ b/activesupport/test/autoloading_fixtures/circular1.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 silence_warnings do
   Circular2
 end
diff --git a/activesupport/test/autoloading_fixtures/circular2.rb b/activesupport/test/autoloading_fixtures/circular2.rb
index c847fa5001..1fdb4c261f 100644
--- a/activesupport/test/autoloading_fixtures/circular2.rb
+++ b/activesupport/test/autoloading_fixtures/circular2.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 Circular1
 
 class Circular2
diff --git a/activesupport/test/autoloading_fixtures/class_folder.rb b/activesupport/test/autoloading_fixtures/class_folder.rb
index ad2b27be61..ff0826c298 100644
--- a/activesupport/test/autoloading_fixtures/class_folder.rb
+++ b/activesupport/test/autoloading_fixtures/class_folder.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class ClassFolder
-  ConstantInClassFolder = 'indeed'
+  ConstantInClassFolder = "indeed"
 end
diff --git a/activesupport/test/autoloading_fixtures/class_folder/class_folder_subclass.rb b/activesupport/test/autoloading_fixtures/class_folder/class_folder_subclass.rb
index 402609c583..cd901e9d71 100644
--- a/activesupport/test/autoloading_fixtures/class_folder/class_folder_subclass.rb
+++ b/activesupport/test/autoloading_fixtures/class_folder/class_folder_subclass.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class ClassFolder::ClassFolderSubclass < ClassFolder
-  ConstantInClassFolder = 'indeed'
+  ConstantInClassFolder = "indeed"
 end
diff --git a/activesupport/test/autoloading_fixtures/class_folder/inline_class.rb b/activesupport/test/autoloading_fixtures/class_folder/inline_class.rb
index 8235e90724..960bfcbc70 100644
--- a/activesupport/test/autoloading_fixtures/class_folder/inline_class.rb
+++ b/activesupport/test/autoloading_fixtures/class_folder/inline_class.rb
@@ -1,2 +1,4 @@
+# frozen_string_literal: true
+
 class ClassFolder::InlineClass
 end
diff --git a/activesupport/test/autoloading_fixtures/class_folder/nested_class.rb b/activesupport/test/autoloading_fixtures/class_folder/nested_class.rb
index 57a13d89ea..98426b797d 100644
--- a/activesupport/test/autoloading_fixtures/class_folder/nested_class.rb
+++ b/activesupport/test/autoloading_fixtures/class_folder/nested_class.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class ClassFolder
   class NestedClass
   end
diff --git a/activesupport/test/autoloading_fixtures/conflict.rb b/activesupport/test/autoloading_fixtures/conflict.rb
index 4ac6201902..c5d3f6bdc0 100644
--- a/activesupport/test/autoloading_fixtures/conflict.rb
+++ b/activesupport/test/autoloading_fixtures/conflict.rb
@@ -1 +1,3 @@
-Conflict = 2
\ No newline at end of file
+# frozen_string_literal: true
+
+Conflict = 2
diff --git a/activesupport/test/autoloading_fixtures/counting_loader.rb b/activesupport/test/autoloading_fixtures/counting_loader.rb
index 4225c4412c..6ac3a9828d 100644
--- a/activesupport/test/autoloading_fixtures/counting_loader.rb
+++ b/activesupport/test/autoloading_fixtures/counting_loader.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 $counting_loaded_times ||= 0
 $counting_loaded_times += 1
 
diff --git a/activesupport/test/autoloading_fixtures/cross_site_dependency.rb b/activesupport/test/autoloading_fixtures/cross_site_dependency.rb
index 21ee554e92..8a18dcff10 100644
--- a/activesupport/test/autoloading_fixtures/cross_site_dependency.rb
+++ b/activesupport/test/autoloading_fixtures/cross_site_dependency.rb
@@ -1,2 +1,4 @@
+# frozen_string_literal: true
+
 class CrossSiteDependency
-end
\ No newline at end of file
+end
diff --git a/activesupport/test/autoloading_fixtures/d.rb b/activesupport/test/autoloading_fixtures/d.rb
index 45c794d4ca..72752d878e 100644
--- a/activesupport/test/autoloading_fixtures/d.rb
+++ b/activesupport/test/autoloading_fixtures/d.rb
@@ -1,2 +1,4 @@
+# frozen_string_literal: true
+
 class D
-end
\ No newline at end of file
+end
diff --git a/activesupport/test/autoloading_fixtures/em.rb b/activesupport/test/autoloading_fixtures/em.rb
index 16a1838667..2e0ac9a6f9 100644
--- a/activesupport/test/autoloading_fixtures/em.rb
+++ b/activesupport/test/autoloading_fixtures/em.rb
@@ -1,2 +1,4 @@
+# frozen_string_literal: true
+
 class EM
-end
\ No newline at end of file
+end
diff --git a/activesupport/test/autoloading_fixtures/html/some_class.rb b/activesupport/test/autoloading_fixtures/html/some_class.rb
index b43d15d891..fbbfd4a214 100644
--- a/activesupport/test/autoloading_fixtures/html/some_class.rb
+++ b/activesupport/test/autoloading_fixtures/html/some_class.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module HTML
   class SomeClass
   end
diff --git a/activesupport/test/autoloading_fixtures/load_path/loaded_constant.rb b/activesupport/test/autoloading_fixtures/load_path/loaded_constant.rb
index e3d1218c96..8735ce87e1 100644
--- a/activesupport/test/autoloading_fixtures/load_path/loaded_constant.rb
+++ b/activesupport/test/autoloading_fixtures/load_path/loaded_constant.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
+
 module LoadedConstant
 end
-
diff --git a/activesupport/test/autoloading_fixtures/loads_constant.rb b/activesupport/test/autoloading_fixtures/loads_constant.rb
index 0b30dc8bca..0bb434a956 100644
--- a/activesupport/test/autoloading_fixtures/loads_constant.rb
+++ b/activesupport/test/autoloading_fixtures/loads_constant.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module LoadsConstant
 end
 
diff --git a/activesupport/test/autoloading_fixtures/module_folder/inline_class.rb b/activesupport/test/autoloading_fixtures/module_folder/inline_class.rb
index ca83437046..c11246b528 100644
--- a/activesupport/test/autoloading_fixtures/module_folder/inline_class.rb
+++ b/activesupport/test/autoloading_fixtures/module_folder/inline_class.rb
@@ -1,2 +1,4 @@
+# frozen_string_literal: true
+
 class ModuleFolder::InlineClass
 end
diff --git a/activesupport/test/autoloading_fixtures/module_folder/nested_class.rb b/activesupport/test/autoloading_fixtures/module_folder/nested_class.rb
index fc4076bd0a..69226b405c 100644
--- a/activesupport/test/autoloading_fixtures/module_folder/nested_class.rb
+++ b/activesupport/test/autoloading_fixtures/module_folder/nested_class.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ModuleFolder
   class NestedClass
   end
diff --git a/activesupport/test/autoloading_fixtures/module_folder/nested_sibling.rb b/activesupport/test/autoloading_fixtures/module_folder/nested_sibling.rb
index 80244b8bab..30de83af11 100644
--- a/activesupport/test/autoloading_fixtures/module_folder/nested_sibling.rb
+++ b/activesupport/test/autoloading_fixtures/module_folder/nested_sibling.rb
@@ -1,2 +1,4 @@
+# frozen_string_literal: true
+
 class ModuleFolder::NestedSibling
-end
\ No newline at end of file
+end
diff --git a/activesupport/test/autoloading_fixtures/module_with_custom_const_missing/a/b.rb b/activesupport/test/autoloading_fixtures/module_with_custom_const_missing/a/b.rb
index d12d02f3aa..f688c1ef35 100644
--- a/activesupport/test/autoloading_fixtures/module_with_custom_const_missing/a/b.rb
+++ b/activesupport/test/autoloading_fixtures/module_with_custom_const_missing/a/b.rb
@@ -1 +1,3 @@
-ModuleWithCustomConstMissing::A::B = "10"
\ No newline at end of file
+# frozen_string_literal: true
+
+ModuleWithCustomConstMissing::A::B = "10"
diff --git a/activesupport/test/autoloading_fixtures/multiple_constant_file.rb b/activesupport/test/autoloading_fixtures/multiple_constant_file.rb
index a9ff4eb89c..1da26e6c2c 100644
--- a/activesupport/test/autoloading_fixtures/multiple_constant_file.rb
+++ b/activesupport/test/autoloading_fixtures/multiple_constant_file.rb
@@ -1,2 +1,4 @@
+# frozen_string_literal: true
+
 MultipleConstantFile = 10
 SiblingConstant = MultipleConstantFile * 2
diff --git a/activesupport/test/autoloading_fixtures/prepend.rb b/activesupport/test/autoloading_fixtures/prepend.rb
new file mode 100644
index 0000000000..bf9e36e12c
--- /dev/null
+++ b/activesupport/test/autoloading_fixtures/prepend.rb
@@ -0,0 +1,10 @@
+# frozen_string_literal: true
+
+class SubClassConflict
+end
+
+class Prepend
+  module PrependedModule
+  end
+  prepend PrependedModule
+end
diff --git a/activesupport/test/autoloading_fixtures/prepend/sub_class_conflict.rb b/activesupport/test/autoloading_fixtures/prepend/sub_class_conflict.rb
new file mode 100644
index 0000000000..506c3c5920
--- /dev/null
+++ b/activesupport/test/autoloading_fixtures/prepend/sub_class_conflict.rb
@@ -0,0 +1,4 @@
+# frozen_string_literal: true
+
+class Prepend::SubClassConflict
+end
diff --git a/activesupport/test/autoloading_fixtures/raises_arbitrary_exception.rb b/activesupport/test/autoloading_fixtures/raises_arbitrary_exception.rb
index 3ca4213c71..118ee6bdd1 100644
--- a/activesupport/test/autoloading_fixtures/raises_arbitrary_exception.rb
+++ b/activesupport/test/autoloading_fixtures/raises_arbitrary_exception.rb
@@ -1,4 +1,6 @@
+# frozen_string_literal: true
+
 RaisesArbitraryException = 1
 _ = A::B # Autoloading recursion, also expected to be watched and discarded.
 
-raise Exception, 'arbitray exception message'
+raise Exception, "arbitrary exception message"
diff --git a/activesupport/test/autoloading_fixtures/raises_name_error.rb b/activesupport/test/autoloading_fixtures/raises_name_error.rb
index a49960abf0..c23afb7b12 100644
--- a/activesupport/test/autoloading_fixtures/raises_name_error.rb
+++ b/activesupport/test/autoloading_fixtures/raises_name_error.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class RaisesNameError
   FooBarBaz
 end
diff --git a/activesupport/test/autoloading_fixtures/raises_no_method_error.rb b/activesupport/test/autoloading_fixtures/raises_no_method_error.rb
index e1b8fce24a..1000ce1cf5 100644
--- a/activesupport/test/autoloading_fixtures/raises_no_method_error.rb
+++ b/activesupport/test/autoloading_fixtures/raises_no_method_error.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class RaisesNoMethodError
   self.foobar_method_doesnt_exist
 end
diff --git a/activesupport/test/autoloading_fixtures/requires_constant.rb b/activesupport/test/autoloading_fixtures/requires_constant.rb
index 14804a0de0..6e51998949 100644
--- a/activesupport/test/autoloading_fixtures/requires_constant.rb
+++ b/activesupport/test/autoloading_fixtures/requires_constant.rb
@@ -1,5 +1,6 @@
+# frozen_string_literal: true
+
 require "loaded_constant"
 
 module RequiresConstant
 end
-
diff --git a/activesupport/test/autoloading_fixtures/should_not_be_required.rb b/activesupport/test/autoloading_fixtures/should_not_be_required.rb
index 1fcf170cc5..8deffa1816 100644
--- a/activesupport/test/autoloading_fixtures/should_not_be_required.rb
+++ b/activesupport/test/autoloading_fixtures/should_not_be_required.rb
@@ -1 +1,3 @@
+# frozen_string_literal: true
+
 ShouldNotBeAutoloaded = 0
diff --git a/activesupport/test/autoloading_fixtures/throws.rb b/activesupport/test/autoloading_fixtures/throws.rb
index e1d96cc512..b6fb391032 100644
--- a/activesupport/test/autoloading_fixtures/throws.rb
+++ b/activesupport/test/autoloading_fixtures/throws.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 Throws = 1
 _ = A::B # Autoloading recursion, expected to be discarded.
 
diff --git a/activesupport/test/autoloading_fixtures/typo.rb b/activesupport/test/autoloading_fixtures/typo.rb
index 8e047f5fd4..d45cddbcf5 100644
--- a/activesupport/test/autoloading_fixtures/typo.rb
+++ b/activesupport/test/autoloading_fixtures/typo.rb
@@ -1,2 +1,3 @@
-TypO = 1
+# frozen_string_literal: true
 
+TypO = 1
diff --git a/activesupport/test/benchmarkable_test.rb b/activesupport/test/benchmarkable_test.rb
index 5af041f458..424da0a52c 100644
--- a/activesupport/test/benchmarkable_test.rb
+++ b/activesupport/test/benchmarkable_test.rb
@@ -1,4 +1,6 @@
-require 'abstract_unit'
+# frozen_string_literal: true
+
+require "abstract_unit"
 
 class BenchmarkableTest < ActiveSupport::TestCase
   include ActiveSupport::Benchmarkable
@@ -36,20 +38,20 @@ class BenchmarkableTest < ActiveSupport::TestCase
 
   def test_with_message
     i_was_run = false
-    benchmark('test_run') { i_was_run = true }
+    benchmark("test_run") { i_was_run = true }
     assert i_was_run
-    assert_last_logged 'test_run'
+    assert_last_logged "test_run"
   end
 
   def test_with_silence
-    assert_difference 'buffer.count', +2 do
-      benchmark('test_run') do
+    assert_difference "buffer.count", +2 do
+      benchmark("test_run") do
         logger.info "SOMETHING"
       end
     end
 
-    assert_difference 'buffer.count', +1 do
-      benchmark('test_run', silence: true) do
+    assert_difference "buffer.count", +1 do
+      benchmark("test_run", silence: true) do
         logger.info "NOTHING"
       end
     end
@@ -57,20 +59,20 @@ class BenchmarkableTest < ActiveSupport::TestCase
 
   def test_within_level
     logger.level = ActiveSupport::Logger::DEBUG
-    benchmark('included_debug_run', :level => :debug) { }
-    assert_last_logged 'included_debug_run'
+    benchmark("included_debug_run", level: :debug) {}
+    assert_last_logged "included_debug_run"
   end
 
   def test_outside_level
     logger.level = ActiveSupport::Logger::ERROR
-    benchmark('skipped_debug_run', :level => :debug) { }
+    benchmark("skipped_debug_run", level: :debug) {}
     assert_no_match(/skipped_debug_run/, buffer.last)
   ensure
     logger.level = ActiveSupport::Logger::DEBUG
   end
 
   private
-    def assert_last_logged(message = 'Benchmarking')
+    def assert_last_logged(message = "Benchmarking")
       assert_match(/^#{message} \(.*\)$/, buffer.last)
     end
 end
diff --git a/activesupport/test/broadcast_logger_test.rb b/activesupport/test/broadcast_logger_test.rb
index f95b3e5ad3..181113e70a 100644
--- a/activesupport/test/broadcast_logger_test.rb
+++ b/activesupport/test/broadcast_logger_test.rb
@@ -1,4 +1,6 @@
-require 'abstract_unit'
+# frozen_string_literal: true
+
+require "abstract_unit"
 
 module ActiveSupport
   class BroadcastLoggerTest < TestCase
@@ -26,8 +28,8 @@ module ActiveSupport
     test "#close broadcasts to all loggers" do
       logger.close
 
-      assert log1.closed, 'should be closed'
-      assert log2.closed, 'should be closed'
+      assert log1.closed, "should be closed"
+      assert log2.closed, "should be closed"
     end
 
     test "#<< shovels the value into all loggers" do
@@ -69,6 +71,20 @@ module ActiveSupport
       assert_equal ::Logger::FATAL, log2.local_level
     end
 
+    test "#silence does not break custom loggers" do
+      new_logger = FakeLogger.new
+      custom_logger = CustomLogger.new
+      custom_logger.extend(Logger.broadcast(new_logger))
+
+      custom_logger.silence do
+        custom_logger.error "from error"
+        custom_logger.unknown "from unknown"
+      end
+
+      assert_equal [[::Logger::ERROR, "from error", nil], [::Logger::UNKNOWN, "from unknown", nil]], custom_logger.adds
+      assert_equal [[::Logger::ERROR, "from error", nil], [::Logger::UNKNOWN, "from unknown", nil]], new_logger.adds
+    end
+
     test "#silence silences all loggers below the default level of ERROR" do
       logger.silence do
         logger.debug "test"
@@ -98,9 +114,7 @@ module ActiveSupport
       assert_equal [[::Logger::FATAL, "seen", nil]], log2.adds
     end
 
-    class FakeLogger
-      include LoggerSilence
-
+    class CustomLogger
       attr_reader :adds, :closed, :chevrons
       attr_accessor :level, :progname, :formatter, :local_level
 
@@ -138,11 +152,11 @@ module ActiveSupport
         add(::Logger::UNKNOWN, message, &block)
       end
 
-      def << x
+      def <<(x)
         @chevrons << x
       end
 
-      def add(message_level, message=nil, progname=nil, &block)
+      def add(message_level, message = nil, progname = nil, &block)
         @adds << [message_level, message, progname] if message_level >= local_level
       end
 
@@ -150,5 +164,9 @@ module ActiveSupport
         @closed = true
       end
     end
+
+    class FakeLogger < CustomLogger
+      include LoggerSilence
+    end
   end
 end
diff --git a/activesupport/test/cache/behaviors.rb b/activesupport/test/cache/behaviors.rb
new file mode 100644
index 0000000000..cb08a10bba
--- /dev/null
+++ b/activesupport/test/cache/behaviors.rb
@@ -0,0 +1,9 @@
+# frozen_string_literal: true
+
+require_relative "behaviors/autoloading_cache_behavior"
+require_relative "behaviors/cache_delete_matched_behavior"
+require_relative "behaviors/cache_increment_decrement_behavior"
+require_relative "behaviors/cache_store_behavior"
+require_relative "behaviors/cache_store_version_behavior"
+require_relative "behaviors/encoded_key_cache_behavior"
+require_relative "behaviors/local_cache_behavior"
diff --git a/activesupport/test/cache/behaviors/autoloading_cache_behavior.rb b/activesupport/test/cache/behaviors/autoloading_cache_behavior.rb
new file mode 100644
index 0000000000..b340eb6c48
--- /dev/null
+++ b/activesupport/test/cache/behaviors/autoloading_cache_behavior.rb
@@ -0,0 +1,43 @@
+# frozen_string_literal: true
+
+require "dependencies_test_helpers"
+
+module AutoloadingCacheBehavior
+  include DependenciesTestHelpers
+
+  def test_simple_autoloading
+    with_autoloading_fixtures do
+      @cache.write("foo", EM.new)
+    end
+
+    remove_constants(:EM)
+    ActiveSupport::Dependencies.clear
+
+    with_autoloading_fixtures do
+      assert_kind_of EM, @cache.read("foo")
+    end
+
+    remove_constants(:EM)
+    ActiveSupport::Dependencies.clear
+  end
+
+  def test_two_classes_autoloading
+    with_autoloading_fixtures do
+      @cache.write("foo", [EM.new, ClassFolder.new])
+    end
+
+    remove_constants(:EM, :ClassFolder)
+    ActiveSupport::Dependencies.clear
+
+    with_autoloading_fixtures do
+      loaded = @cache.read("foo")
+      assert_kind_of Array, loaded
+      assert_equal 2, loaded.size
+      assert_kind_of EM, loaded[0]
+      assert_kind_of ClassFolder, loaded[1]
+    end
+
+    remove_constants(:EM, :ClassFolder)
+    ActiveSupport::Dependencies.clear
+  end
+end
diff --git a/activesupport/test/cache/behaviors/cache_delete_matched_behavior.rb b/activesupport/test/cache/behaviors/cache_delete_matched_behavior.rb
new file mode 100644
index 0000000000..6f59ce48d2
--- /dev/null
+++ b/activesupport/test/cache/behaviors/cache_delete_matched_behavior.rb
@@ -0,0 +1,15 @@
+# frozen_string_literal: true
+
+module CacheDeleteMatchedBehavior
+  def test_delete_matched
+    @cache.write("foo", "bar")
+    @cache.write("fu", "baz")
+    @cache.write("foo/bar", "baz")
+    @cache.write("fu/baz", "bar")
+    @cache.delete_matched(/oo/)
+    assert !@cache.exist?("foo")
+    assert @cache.exist?("fu")
+    assert !@cache.exist?("foo/bar")
+    assert @cache.exist?("fu/baz")
+  end
+end
diff --git a/activesupport/test/cache/behaviors/cache_increment_decrement_behavior.rb b/activesupport/test/cache/behaviors/cache_increment_decrement_behavior.rb
new file mode 100644
index 0000000000..16b7abc679
--- /dev/null
+++ b/activesupport/test/cache/behaviors/cache_increment_decrement_behavior.rb
@@ -0,0 +1,27 @@
+# frozen_string_literal: true
+
+module CacheIncrementDecrementBehavior
+  def test_increment
+    @cache.write("foo", 1, raw: true)
+    assert_equal 1, @cache.read("foo").to_i
+    assert_equal 2, @cache.increment("foo")
+    assert_equal 2, @cache.read("foo").to_i
+    assert_equal 3, @cache.increment("foo")
+    assert_equal 3, @cache.read("foo").to_i
+
+    missing = @cache.increment("bar")
+    assert(missing.nil? || missing == 1)
+  end
+
+  def test_decrement
+    @cache.write("foo", 3, raw: true)
+    assert_equal 3, @cache.read("foo").to_i
+    assert_equal 2, @cache.decrement("foo")
+    assert_equal 2, @cache.read("foo").to_i
+    assert_equal 1, @cache.decrement("foo")
+    assert_equal 1, @cache.read("foo").to_i
+
+    missing = @cache.decrement("bar")
+    assert(missing.nil? || missing == -1)
+  end
+end
diff --git a/activesupport/test/cache/behaviors/cache_store_behavior.rb b/activesupport/test/cache/behaviors/cache_store_behavior.rb
new file mode 100644
index 0000000000..bdc689b8b4
--- /dev/null
+++ b/activesupport/test/cache/behaviors/cache_store_behavior.rb
@@ -0,0 +1,353 @@
+# frozen_string_literal: true
+
+# Tests the base functionality that should be identical across all cache stores.
+module CacheStoreBehavior
+  def test_should_read_and_write_strings
+    assert @cache.write("foo", "bar")
+    assert_equal "bar", @cache.read("foo")
+  end
+
+  def test_should_overwrite
+    @cache.write("foo", "bar")
+    @cache.write("foo", "baz")
+    assert_equal "baz", @cache.read("foo")
+  end
+
+  def test_fetch_without_cache_miss
+    @cache.write("foo", "bar")
+    assert_not_called(@cache, :write) do
+      assert_equal "bar", @cache.fetch("foo") { "baz" }
+    end
+  end
+
+  def test_fetch_with_cache_miss
+    assert_called_with(@cache, :write, ["foo", "baz", @cache.options]) do
+      assert_equal "baz", @cache.fetch("foo") { "baz" }
+    end
+  end
+
+  def test_fetch_with_cache_miss_passes_key_to_block
+    cache_miss = false
+    assert_equal 3, @cache.fetch("foo") { |key| cache_miss = true; key.length }
+    assert cache_miss
+
+    cache_miss = false
+    assert_equal 3, @cache.fetch("foo") { |key| cache_miss = true; key.length }
+    assert !cache_miss
+  end
+
+  def test_fetch_with_forced_cache_miss
+    @cache.write("foo", "bar")
+    assert_not_called(@cache, :read) do
+      assert_called_with(@cache, :write, ["foo", "bar", @cache.options.merge(force: true)]) do
+        @cache.fetch("foo", force: true) { "bar" }
+      end
+    end
+  end
+
+  def test_fetch_with_cached_nil
+    @cache.write("foo", nil)
+    assert_not_called(@cache, :write) do
+      assert_nil @cache.fetch("foo") { "baz" }
+    end
+  end
+
+  def test_fetch_with_forced_cache_miss_with_block
+    @cache.write("foo", "bar")
+    assert_equal "foo_bar", @cache.fetch("foo", force: true) { "foo_bar" }
+  end
+
+  def test_fetch_with_forced_cache_miss_without_block
+    @cache.write("foo", "bar")
+    assert_raises(ArgumentError) do
+      @cache.fetch("foo", force: true)
+    end
+
+    assert_equal "bar", @cache.read("foo")
+  end
+
+  def test_should_read_and_write_hash
+    assert @cache.write("foo", a: "b")
+    assert_equal({ a: "b" }, @cache.read("foo"))
+  end
+
+  def test_should_read_and_write_integer
+    assert @cache.write("foo", 1)
+    assert_equal 1, @cache.read("foo")
+  end
+
+  def test_should_read_and_write_nil
+    assert @cache.write("foo", nil)
+    assert_nil @cache.read("foo")
+  end
+
+  def test_should_read_and_write_false
+    assert @cache.write("foo", false)
+    assert_equal false, @cache.read("foo")
+  end
+
+  def test_read_multi
+    @cache.write("foo", "bar")
+    @cache.write("fu", "baz")
+    @cache.write("fud", "biz")
+    assert_equal({ "foo" => "bar", "fu" => "baz" }, @cache.read_multi("foo", "fu"))
+  end
+
+  def test_read_multi_with_expires
+    time = Time.now
+    @cache.write("foo", "bar", expires_in: 10)
+    @cache.write("fu", "baz")
+    @cache.write("fud", "biz")
+    Time.stub(:now, time + 11) do
+      assert_equal({ "fu" => "baz" }, @cache.read_multi("foo", "fu"))
+    end
+  end
+
+  def test_fetch_multi
+    @cache.write("foo", "bar")
+    @cache.write("fud", "biz")
+
+    values = @cache.fetch_multi("foo", "fu", "fud") { |value| value * 2 }
+
+    assert_equal({ "foo" => "bar", "fu" => "fufu", "fud" => "biz" }, values)
+    assert_equal("fufu", @cache.read("fu"))
+  end
+
+  def test_multi_with_objects
+    cache_struct = Struct.new(:cache_key, :title)
+    foo = cache_struct.new("foo", "FOO!")
+    bar = cache_struct.new("bar")
+
+    @cache.write("bar", "BAM!")
+
+    values = @cache.fetch_multi(foo, bar) { |object| object.title }
+
+    assert_equal({ foo => "FOO!", bar => "BAM!" }, values)
+  end
+
+  def test_fetch_multi_without_block
+    assert_raises(ArgumentError) do
+      @cache.fetch_multi("foo")
+    end
+  end
+
+  def test_read_and_write_compressed_small_data
+    @cache.write("foo", "bar", compress: true)
+    assert_equal "bar", @cache.read("foo")
+  end
+
+  def test_read_and_write_compressed_large_data
+    @cache.write("foo", "bar", compress: true, compress_threshold: 2)
+    assert_equal "bar", @cache.read("foo")
+  end
+
+  def test_read_and_write_compressed_nil
+    @cache.write("foo", nil, compress: true)
+    assert_nil @cache.read("foo")
+  end
+
+  def test_read_and_write_uncompressed_small_data
+    @cache.write("foo", "bar", compress: false)
+    assert_equal "bar", @cache.read("foo")
+  end
+
+  def test_read_and_write_uncompressed_nil
+    @cache.write("foo", nil, compress: false)
+    assert_nil @cache.read("foo")
+  end
+
+  def test_cache_key
+    obj = Object.new
+    def obj.cache_key
+      :foo
+    end
+    @cache.write(obj, "bar")
+    assert_equal "bar", @cache.read("foo")
+  end
+
+  def test_param_as_cache_key
+    obj = Object.new
+    def obj.to_param
+      "foo"
+    end
+    @cache.write(obj, "bar")
+    assert_equal "bar", @cache.read("foo")
+  end
+
+  def test_unversioned_cache_key
+    obj = Object.new
+    def obj.cache_key
+      "foo"
+    end
+    def obj.cache_key_with_version
+      "foo-v1"
+    end
+    @cache.write(obj, "bar")
+    assert_equal "bar", @cache.read("foo")
+  end
+
+  def test_array_as_cache_key
+    @cache.write([:fu, "foo"], "bar")
+    assert_equal "bar", @cache.read("fu/foo")
+  end
+
+  def test_hash_as_cache_key
+    @cache.write({ foo: 1, fu: 2 }, "bar")
+    assert_equal "bar", @cache.read("foo=1/fu=2")
+  end
+
+  def test_keys_are_case_sensitive
+    @cache.write("foo", "bar")
+    assert_nil @cache.read("FOO")
+  end
+
+  def test_exist
+    @cache.write("foo", "bar")
+    assert_equal true, @cache.exist?("foo")
+    assert_equal false, @cache.exist?("bar")
+  end
+
+  def test_nil_exist
+    @cache.write("foo", nil)
+    assert @cache.exist?("foo")
+  end
+
+  def test_delete
+    @cache.write("foo", "bar")
+    assert @cache.exist?("foo")
+    assert @cache.delete("foo")
+    assert !@cache.exist?("foo")
+  end
+
+  def test_original_store_objects_should_not_be_immutable
+    bar = "bar".dup
+    @cache.write("foo", bar)
+    assert_nothing_raised { bar.gsub!(/.*/, "baz") }
+  end
+
+  def test_expires_in
+    time = Time.local(2008, 4, 24)
+
+    Time.stub(:now, time) do
+      @cache.write("foo", "bar")
+      assert_equal "bar", @cache.read("foo")
+    end
+
+    Time.stub(:now, time + 30) do
+      assert_equal "bar", @cache.read("foo")
+    end
+
+    Time.stub(:now, time + 61) do
+      assert_nil @cache.read("foo")
+    end
+  end
+
+  def test_race_condition_protection_skipped_if_not_defined
+    @cache.write("foo", "bar")
+    time = @cache.send(:read_entry, @cache.send(:normalize_key, "foo", {}), {}).expires_at
+
+    Time.stub(:now, Time.at(time)) do
+      result = @cache.fetch("foo") do
+        assert_nil @cache.read("foo")
+        "baz"
+      end
+      assert_equal "baz", result
+    end
+  end
+
+  def test_race_condition_protection_is_limited
+    time = Time.now
+    @cache.write("foo", "bar", expires_in: 60)
+    Time.stub(:now, time + 71) do
+      result = @cache.fetch("foo", race_condition_ttl: 10) do
+        assert_nil @cache.read("foo")
+        "baz"
+      end
+      assert_equal "baz", result
+    end
+  end
+
+  def test_race_condition_protection_is_safe
+    time = Time.now
+    @cache.write("foo", "bar", expires_in: 60)
+    Time.stub(:now, time + 61) do
+      begin
+        @cache.fetch("foo", race_condition_ttl: 10) do
+          assert_equal "bar", @cache.read("foo")
+          raise ArgumentError.new
+        end
+      rescue ArgumentError
+      end
+      assert_equal "bar", @cache.read("foo")
+    end
+    Time.stub(:now, time + 91) do
+      assert_nil @cache.read("foo")
+    end
+  end
+
+  def test_race_condition_protection
+    time = Time.now
+    @cache.write("foo", "bar", expires_in: 60)
+    Time.stub(:now, time + 61) do
+      result = @cache.fetch("foo", race_condition_ttl: 10) do
+        assert_equal "bar", @cache.read("foo")
+        "baz"
+      end
+      assert_equal "baz", result
+    end
+  end
+
+  def test_crazy_key_characters
+    crazy_key = "#/:*(<+=> )&$%@?;'\"\'`~-"
+    assert @cache.write(crazy_key, "1", raw: true)
+    assert_equal "1", @cache.read(crazy_key)
+    assert_equal "1", @cache.fetch(crazy_key)
+    assert @cache.delete(crazy_key)
+    assert_equal "2", @cache.fetch(crazy_key, raw: true) { "2" }
+    assert_equal 3, @cache.increment(crazy_key)
+    assert_equal 2, @cache.decrement(crazy_key)
+  end
+
+  def test_really_long_keys
+    key = "".dup
+    900.times { key << "x" }
+    assert @cache.write(key, "bar")
+    assert_equal "bar", @cache.read(key)
+    assert_equal "bar", @cache.fetch(key)
+    assert_nil @cache.read("#{key}x")
+    assert_equal({ key => "bar" }, @cache.read_multi(key))
+    assert @cache.delete(key)
+  end
+
+  def test_cache_hit_instrumentation
+    key = "test_key"
+    @events = []
+    ActiveSupport::Notifications.subscribe "cache_read.active_support" do |*args|
+      @events << ActiveSupport::Notifications::Event.new(*args)
+    end
+    assert @cache.write(key, "1", raw: true)
+    assert @cache.fetch(key) {}
+    assert_equal 1, @events.length
+    assert_equal "cache_read.active_support", @events[0].name
+    assert_equal :fetch, @events[0].payload[:super_operation]
+    assert @events[0].payload[:hit]
+  ensure
+    ActiveSupport::Notifications.unsubscribe "cache_read.active_support"
+  end
+
+  def test_cache_miss_instrumentation
+    @events = []
+    ActiveSupport::Notifications.subscribe(/^cache_(.*)\.active_support$/) do |*args|
+      @events << ActiveSupport::Notifications::Event.new(*args)
+    end
+    assert_not @cache.fetch("bad_key") {}
+    assert_equal 3, @events.length
+    assert_equal "cache_read.active_support", @events[0].name
+    assert_equal "cache_generate.active_support", @events[1].name
+    assert_equal "cache_write.active_support", @events[2].name
+    assert_equal :fetch, @events[0].payload[:super_operation]
+    assert_not @events[0].payload[:hit]
+  ensure
+    ActiveSupport::Notifications.unsubscribe "cache_read.active_support"
+  end
+end
diff --git a/activesupport/test/cache/behaviors/cache_store_version_behavior.rb b/activesupport/test/cache/behaviors/cache_store_version_behavior.rb
new file mode 100644
index 0000000000..c2e4d046af
--- /dev/null
+++ b/activesupport/test/cache/behaviors/cache_store_version_behavior.rb
@@ -0,0 +1,88 @@
+# frozen_string_literal: true
+
+module CacheStoreVersionBehavior
+  ModelWithKeyAndVersion = Struct.new(:cache_key, :cache_version)
+
+  def test_fetch_with_right_version_should_hit
+    @cache.fetch("foo", version: 1) { "bar" }
+    assert_equal "bar", @cache.read("foo", version: 1)
+  end
+
+  def test_fetch_with_wrong_version_should_miss
+    @cache.fetch("foo", version: 1) { "bar" }
+    assert_nil @cache.read("foo", version: 2)
+  end
+
+  def test_read_with_right_version_should_hit
+    @cache.write("foo", "bar", version: 1)
+    assert_equal "bar", @cache.read("foo", version: 1)
+  end
+
+  def test_read_with_wrong_version_should_miss
+    @cache.write("foo", "bar", version: 1)
+    assert_nil @cache.read("foo", version: 2)
+  end
+
+  def test_exist_with_right_version_should_be_true
+    @cache.write("foo", "bar", version: 1)
+    assert @cache.exist?("foo", version: 1)
+  end
+
+  def test_exist_with_wrong_version_should_be_false
+    @cache.write("foo", "bar", version: 1)
+    assert !@cache.exist?("foo", version: 2)
+  end
+
+  def test_reading_and_writing_with_model_supporting_cache_version
+    m1v1 = ModelWithKeyAndVersion.new("model/1", 1)
+    m1v2 = ModelWithKeyAndVersion.new("model/1", 2)
+
+    @cache.write(m1v1, "bar")
+    assert_equal "bar", @cache.read(m1v1)
+    assert_nil @cache.read(m1v2)
+  end
+
+  def test_reading_and_writing_with_model_supporting_cache_version_using_nested_key
+    m1v1 = ModelWithKeyAndVersion.new("model/1", 1)
+    m1v2 = ModelWithKeyAndVersion.new("model/1", 2)
+
+    @cache.write([ "something", m1v1 ], "bar")
+    assert_equal "bar", @cache.read([ "something", m1v1 ])
+    assert_nil @cache.read([ "something", m1v2 ])
+  end
+
+  def test_fetching_with_model_supporting_cache_version
+    m1v1 = ModelWithKeyAndVersion.new("model/1", 1)
+    m1v2 = ModelWithKeyAndVersion.new("model/1", 2)
+
+    @cache.fetch(m1v1) { "bar" }
+    assert_equal "bar", @cache.fetch(m1v1) { "bu" }
+    assert_equal "bu", @cache.fetch(m1v2) { "bu" }
+  end
+
+  def test_exist_with_model_supporting_cache_version
+    m1v1 = ModelWithKeyAndVersion.new("model/1", 1)
+    m1v2 = ModelWithKeyAndVersion.new("model/1", 2)
+
+    @cache.write(m1v1, "bar")
+    assert     @cache.exist?(m1v1)
+    assert_not @cache.fetch(m1v2)
+  end
+
+  def test_fetch_multi_with_model_supporting_cache_version
+    m1v1 = ModelWithKeyAndVersion.new("model/1", 1)
+    m2v1 = ModelWithKeyAndVersion.new("model/2", 1)
+    m2v2 = ModelWithKeyAndVersion.new("model/2", 2)
+
+    first_fetch_values  = @cache.fetch_multi(m1v1, m2v1) { |m| m.cache_key }
+    second_fetch_values = @cache.fetch_multi(m1v1, m2v2) { |m| m.cache_key + " 2nd" }
+
+    assert_equal({ m1v1 => "model/1", m2v1 => "model/2" }, first_fetch_values)
+    assert_equal({ m1v1 => "model/1", m2v2 => "model/2 2nd" }, second_fetch_values)
+  end
+
+  def test_version_is_normalized
+    @cache.write("foo", "bar", version: 1)
+    assert_equal "bar", @cache.read("foo", version: "1")
+  end
+end
diff --git a/activesupport/test/cache/behaviors/encoded_key_cache_behavior.rb b/activesupport/test/cache/behaviors/encoded_key_cache_behavior.rb
new file mode 100644
index 0000000000..da16142496
--- /dev/null
+++ b/activesupport/test/cache/behaviors/encoded_key_cache_behavior.rb
@@ -0,0 +1,36 @@
+# frozen_string_literal: true
+
+# https://rails.lighthouseapp.com/projects/8994/tickets/6225-memcachestore-cant-deal-with-umlauts-and-special-characters
+# The error is caused by character encodings that can't be compared with ASCII-8BIT regular expressions and by special
+# characters like the umlaut in UTF-8.
+module EncodedKeyCacheBehavior
+  Encoding.list.each do |encoding|
+    define_method "test_#{encoding.name.underscore}_encoded_values" do
+      key = "foo".dup.force_encoding(encoding)
+      assert @cache.write(key, "1", raw: true)
+      assert_equal "1", @cache.read(key)
+      assert_equal "1", @cache.fetch(key)
+      assert @cache.delete(key)
+      assert_equal "2", @cache.fetch(key, raw: true) { "2" }
+      assert_equal 3, @cache.increment(key)
+      assert_equal 2, @cache.decrement(key)
+    end
+  end
+
+  def test_common_utf8_values
+    key = "\xC3\xBCmlaut".dup.force_encoding(Encoding::UTF_8)
+    assert @cache.write(key, "1", raw: true)
+    assert_equal "1", @cache.read(key)
+    assert_equal "1", @cache.fetch(key)
+    assert @cache.delete(key)
+    assert_equal "2", @cache.fetch(key, raw: true) { "2" }
+    assert_equal 3, @cache.increment(key)
+    assert_equal 2, @cache.decrement(key)
+  end
+
+  def test_retains_encoding
+    key = "\xC3\xBCmlaut".dup.force_encoding(Encoding::UTF_8)
+    assert @cache.write(key, "1", raw: true)
+    assert_equal Encoding::UTF_8, key.encoding
+  end
+end
diff --git a/activesupport/test/cache/behaviors/local_cache_behavior.rb b/activesupport/test/cache/behaviors/local_cache_behavior.rb
new file mode 100644
index 0000000000..f7302df4c8
--- /dev/null
+++ b/activesupport/test/cache/behaviors/local_cache_behavior.rb
@@ -0,0 +1,132 @@
+# frozen_string_literal: true
+
+module LocalCacheBehavior
+  def test_local_writes_are_persistent_on_the_remote_cache
+    retval = @cache.with_local_cache do
+      @cache.write("foo", "bar")
+    end
+    assert retval
+    assert_equal "bar", @cache.read("foo")
+  end
+
+  def test_clear_also_clears_local_cache
+    @cache.with_local_cache do
+      @cache.write("foo", "bar")
+      @cache.clear
+      assert_nil @cache.read("foo")
+    end
+
+    assert_nil @cache.read("foo")
+  end
+
+  def test_cleanup_clears_local_cache_but_not_remote_cache
+    begin
+      @cache.cleanup
+    rescue NotImplementedError
+      skip
+    end
+
+    @cache.with_local_cache do
+      @cache.write("foo", "bar")
+      assert_equal "bar", @cache.read("foo")
+
+      @cache.send(:bypass_local_cache) { @cache.write("foo", "baz") }
+      assert_equal "bar", @cache.read("foo")
+
+      @cache.cleanup
+      assert_equal "baz", @cache.read("foo")
+    end
+  end
+
+  def test_local_cache_of_write
+    @cache.with_local_cache do
+      @cache.write("foo", "bar")
+      @peek.delete("foo")
+      assert_equal "bar", @cache.read("foo")
+    end
+  end
+
+  def test_local_cache_of_read
+    @cache.write("foo", "bar")
+    @cache.with_local_cache do
+      assert_equal "bar", @cache.read("foo")
+    end
+  end
+
+  def test_local_cache_of_read_nil
+    @cache.with_local_cache do
+      assert_nil @cache.read("foo")
+      @cache.send(:bypass_local_cache) { @cache.write "foo", "bar" }
+      assert_nil @cache.read("foo")
+    end
+  end
+
+  def test_local_cache_fetch
+    @cache.with_local_cache do
+      @cache.send(:local_cache).write "foo", "bar"
+      assert_equal "bar", @cache.send(:local_cache).fetch("foo")
+    end
+  end
+
+  def test_local_cache_of_write_nil
+    @cache.with_local_cache do
+      assert @cache.write("foo", nil)
+      assert_nil @cache.read("foo")
+      @peek.write("foo", "bar")
+      assert_nil @cache.read("foo")
+    end
+  end
+
+  def test_local_cache_of_write_with_unless_exist
+    @cache.with_local_cache do
+      @cache.write("foo", "bar")
+      @cache.write("foo", "baz", unless_exist: true)
+      assert_equal @peek.read("foo"), @cache.read("foo")
+    end
+  end
+
+  def test_local_cache_of_delete
+    @cache.with_local_cache do
+      @cache.write("foo", "bar")
+      @cache.delete("foo")
+      assert_nil @cache.read("foo")
+    end
+  end
+
+  def test_local_cache_of_exist
+    @cache.with_local_cache do
+      @cache.write("foo", "bar")
+      @peek.delete("foo")
+      assert @cache.exist?("foo")
+    end
+  end
+
+  def test_local_cache_of_increment
+    @cache.with_local_cache do
+      @cache.write("foo", 1, raw: true)
+      @peek.write("foo", 2, raw: true)
+      @cache.increment("foo")
+      assert_equal 3, @cache.read("foo")
+    end
+  end
+
+  def test_local_cache_of_decrement
+    @cache.with_local_cache do
+      @cache.write("foo", 1, raw: true)
+      @peek.write("foo", 3, raw: true)
+      @cache.decrement("foo")
+      assert_equal 2, @cache.read("foo")
+    end
+  end
+
+  def test_middleware
+    app = lambda { |env|
+      result = @cache.write("foo", "bar")
+      assert_equal "bar", @cache.read("foo") # make sure 'foo' was written
+      assert result
+      [200, {}, []]
+    }
+    app = @cache.middleware.new(app)
+    app.call({})
+  end
+end
diff --git a/activesupport/test/cache/cache_entry_test.rb b/activesupport/test/cache/cache_entry_test.rb
new file mode 100644
index 0000000000..80ff7ad564
--- /dev/null
+++ b/activesupport/test/cache/cache_entry_test.rb
@@ -0,0 +1,37 @@
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "active_support/cache"
+
+class CacheEntryTest < ActiveSupport::TestCase
+  def test_expired
+    entry = ActiveSupport::Cache::Entry.new("value")
+    assert !entry.expired?, "entry not expired"
+    entry = ActiveSupport::Cache::Entry.new("value", expires_in: 60)
+    assert !entry.expired?, "entry not expired"
+    Time.stub(:now, Time.now + 61) do
+      assert entry.expired?, "entry is expired"
+    end
+  end
+
+  def test_compressed_values
+    value = "value" * 100
+    entry = ActiveSupport::Cache::Entry.new(value, compress: true, compress_threshold: 1)
+    assert_equal value, entry.value
+    assert(value.bytesize > entry.size, "value is compressed")
+  end
+
+  def test_compressed_by_default
+    value = "value" * 100
+    entry = ActiveSupport::Cache::Entry.new(value, compress_threshold: 1)
+    assert_equal value, entry.value
+    assert(value.bytesize > entry.size, "value is compressed")
+  end
+
+  def test_uncompressed_values
+    value = "value" * 100
+    entry = ActiveSupport::Cache::Entry.new(value, compress: false)
+    assert_equal value, entry.value
+    assert_equal value.bytesize, entry.size
+  end
+end
diff --git a/activesupport/test/cache/cache_key_test.rb b/activesupport/test/cache/cache_key_test.rb
new file mode 100644
index 0000000000..84e656f504
--- /dev/null
+++ b/activesupport/test/cache/cache_key_test.rb
@@ -0,0 +1,90 @@
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "active_support/cache"
+
+class CacheKeyTest < ActiveSupport::TestCase
+  def test_entry_legacy_optional_ivars
+    legacy = Class.new(ActiveSupport::Cache::Entry) do
+      def initialize(value, options = {})
+        @value = value
+        @expires_in = nil
+        @created_at = nil
+        super
+      end
+    end
+
+    entry = legacy.new "foo"
+    assert_equal "foo", entry.value
+  end
+
+  def test_expand_cache_key
+    assert_equal "1/2/true", ActiveSupport::Cache.expand_cache_key([1, "2", true])
+    assert_equal "name/1/2/true", ActiveSupport::Cache.expand_cache_key([1, "2", true], :name)
+  end
+
+  def test_expand_cache_key_with_rails_cache_id
+    with_env("RAILS_CACHE_ID" => "c99") do
+      assert_equal "c99/foo", ActiveSupport::Cache.expand_cache_key(:foo)
+      assert_equal "c99/foo", ActiveSupport::Cache.expand_cache_key([:foo])
+      assert_equal "c99/foo/bar", ActiveSupport::Cache.expand_cache_key([:foo, :bar])
+      assert_equal "nm/c99/foo", ActiveSupport::Cache.expand_cache_key(:foo, :nm)
+      assert_equal "nm/c99/foo", ActiveSupport::Cache.expand_cache_key([:foo], :nm)
+      assert_equal "nm/c99/foo/bar", ActiveSupport::Cache.expand_cache_key([:foo, :bar], :nm)
+    end
+  end
+
+  def test_expand_cache_key_with_rails_app_version
+    with_env("RAILS_APP_VERSION" => "rails3") do
+      assert_equal "rails3/foo", ActiveSupport::Cache.expand_cache_key(:foo)
+    end
+  end
+
+  def test_expand_cache_key_rails_cache_id_should_win_over_rails_app_version
+    with_env("RAILS_CACHE_ID" => "c99", "RAILS_APP_VERSION" => "rails3") do
+      assert_equal "c99/foo", ActiveSupport::Cache.expand_cache_key(:foo)
+    end
+  end
+
+  def test_expand_cache_key_respond_to_cache_key
+    key = "foo".dup
+    def key.cache_key
+      :foo_key
+    end
+    assert_equal "foo_key", ActiveSupport::Cache.expand_cache_key(key)
+  end
+
+  def test_expand_cache_key_array_with_something_that_responds_to_cache_key
+    key = "foo".dup
+    def key.cache_key
+      :foo_key
+    end
+    assert_equal "foo_key", ActiveSupport::Cache.expand_cache_key([key])
+  end
+
+  def test_expand_cache_key_of_nil
+    assert_equal "", ActiveSupport::Cache.expand_cache_key(nil)
+  end
+
+  def test_expand_cache_key_of_false
+    assert_equal "false", ActiveSupport::Cache.expand_cache_key(false)
+  end
+
+  def test_expand_cache_key_of_true
+    assert_equal "true", ActiveSupport::Cache.expand_cache_key(true)
+  end
+
+  def test_expand_cache_key_of_array_like_object
+    assert_equal "foo/bar/baz", ActiveSupport::Cache.expand_cache_key(%w{foo bar baz}.to_enum)
+  end
+
+  private
+
+    def with_env(kv)
+      old_values = {}
+      kv.each { |key, value| old_values[key], ENV[key] = ENV[key], value }
+      yield
+    ensure
+      old_values.each { |key, value| ENV[key] = value }
+    end
+end
diff --git a/activesupport/test/cache/cache_store_logger_test.rb b/activesupport/test/cache/cache_store_logger_test.rb
new file mode 100644
index 0000000000..1af6893cc9
--- /dev/null
+++ b/activesupport/test/cache/cache_store_logger_test.rb
@@ -0,0 +1,36 @@
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "active_support/cache"
+
+class CacheStoreLoggerTest < ActiveSupport::TestCase
+  def setup
+    @cache = ActiveSupport::Cache.lookup_store(:memory_store)
+
+    @buffer = StringIO.new
+    @cache.logger = ActiveSupport::Logger.new(@buffer)
+  end
+
+  def test_logging
+    @cache.fetch("foo") { "bar" }
+    assert @buffer.string.present?
+  end
+
+  def test_log_with_string_namespace
+    @cache.fetch("foo", namespace: "string_namespace") { "bar" }
+    assert_match %r{string_namespace:foo}, @buffer.string
+  end
+
+  def test_log_with_proc_namespace
+    proc = Proc.new do
+      "proc_namespace"
+    end
+    @cache.fetch("foo", namespace: proc) { "bar" }
+    assert_match %r{proc_namespace:foo}, @buffer.string
+  end
+
+  def test_mute_logging
+    @cache.mute { @cache.fetch("foo") { "bar" } }
+    assert @buffer.string.blank?
+  end
+end
diff --git a/activesupport/test/cache/cache_store_namespace_test.rb b/activesupport/test/cache/cache_store_namespace_test.rb
new file mode 100644
index 0000000000..b52a61c500
--- /dev/null
+++ b/activesupport/test/cache/cache_store_namespace_test.rb
@@ -0,0 +1,40 @@
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "active_support/cache"
+
+class CacheStoreNamespaceTest < ActiveSupport::TestCase
+  def test_static_namespace
+    cache = ActiveSupport::Cache.lookup_store(:memory_store, namespace: "tester")
+    cache.write("foo", "bar")
+    assert_equal "bar", cache.read("foo")
+    assert_equal "bar", cache.instance_variable_get(:@data)["tester:foo"].value
+  end
+
+  def test_proc_namespace
+    test_val = "tester"
+    proc = lambda { test_val }
+    cache = ActiveSupport::Cache.lookup_store(:memory_store, namespace: proc)
+    cache.write("foo", "bar")
+    assert_equal "bar", cache.read("foo")
+    assert_equal "bar", cache.instance_variable_get(:@data)["tester:foo"].value
+  end
+
+  def test_delete_matched_key_start
+    cache = ActiveSupport::Cache.lookup_store(:memory_store, namespace: "tester")
+    cache.write("foo", "bar")
+    cache.write("fu", "baz")
+    cache.delete_matched(/^fo/)
+    assert !cache.exist?("foo")
+    assert cache.exist?("fu")
+  end
+
+  def test_delete_matched_key
+    cache = ActiveSupport::Cache.lookup_store(:memory_store, namespace: "foo")
+    cache.write("foo", "bar")
+    cache.write("fu", "baz")
+    cache.delete_matched(/OO/i)
+    assert !cache.exist?("foo")
+    assert cache.exist?("fu")
+  end
+end
diff --git a/activesupport/test/cache/cache_store_setting_test.rb b/activesupport/test/cache/cache_store_setting_test.rb
new file mode 100644
index 0000000000..368cb39f97
--- /dev/null
+++ b/activesupport/test/cache/cache_store_setting_test.rb
@@ -0,0 +1,68 @@
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "active_support/cache"
+require "dalli"
+
+class CacheStoreSettingTest < ActiveSupport::TestCase
+  def test_memory_store_gets_created_if_no_arguments_passed_to_lookup_store_method
+    store = ActiveSupport::Cache.lookup_store
+    assert_kind_of(ActiveSupport::Cache::MemoryStore, store)
+  end
+
+  def test_memory_store
+    store = ActiveSupport::Cache.lookup_store :memory_store
+    assert_kind_of(ActiveSupport::Cache::MemoryStore, store)
+  end
+
+  def test_file_fragment_cache_store
+    store = ActiveSupport::Cache.lookup_store :file_store, "/path/to/cache/directory"
+    assert_kind_of(ActiveSupport::Cache::FileStore, store)
+    assert_equal "/path/to/cache/directory", store.cache_path
+  end
+
+  def test_mem_cache_fragment_cache_store
+    assert_called_with(Dalli::Client, :new, [%w[localhost], {}]) do
+      store = ActiveSupport::Cache.lookup_store :mem_cache_store, "localhost"
+      assert_kind_of(ActiveSupport::Cache::MemCacheStore, store)
+    end
+  end
+
+  def test_mem_cache_fragment_cache_store_with_given_mem_cache
+    mem_cache = Dalli::Client.new
+    assert_not_called(Dalli::Client, :new) do
+      store = ActiveSupport::Cache.lookup_store :mem_cache_store, mem_cache
+      assert_kind_of(ActiveSupport::Cache::MemCacheStore, store)
+    end
+  end
+
+  def test_mem_cache_fragment_cache_store_with_not_dalli_client
+    assert_not_called(Dalli::Client, :new) do
+      memcache = Object.new
+      assert_raises(ArgumentError) do
+        ActiveSupport::Cache.lookup_store :mem_cache_store, memcache
+      end
+    end
+  end
+
+  def test_mem_cache_fragment_cache_store_with_multiple_servers
+    assert_called_with(Dalli::Client, :new, [%w[localhost 192.168.1.1], {}]) do
+      store = ActiveSupport::Cache.lookup_store :mem_cache_store, "localhost", "192.168.1.1"
+      assert_kind_of(ActiveSupport::Cache::MemCacheStore, store)
+    end
+  end
+
+  def test_mem_cache_fragment_cache_store_with_options
+    assert_called_with(Dalli::Client, :new, [%w[localhost 192.168.1.1], { timeout: 10 }]) do
+      store = ActiveSupport::Cache.lookup_store :mem_cache_store, "localhost", "192.168.1.1", namespace: "foo", timeout: 10
+      assert_kind_of(ActiveSupport::Cache::MemCacheStore, store)
+      assert_equal "foo", store.options[:namespace]
+    end
+  end
+
+  def test_object_assigned_fragment_cache_store
+    store = ActiveSupport::Cache.lookup_store ActiveSupport::Cache::FileStore.new("/path/to/cache/directory")
+    assert_kind_of(ActiveSupport::Cache::FileStore, store)
+    assert_equal "/path/to/cache/directory", store.cache_path
+  end
+end
diff --git a/activesupport/test/cache/cache_store_write_multi_test.rb b/activesupport/test/cache/cache_store_write_multi_test.rb
new file mode 100644
index 0000000000..5b6fd678c5
--- /dev/null
+++ b/activesupport/test/cache/cache_store_write_multi_test.rb
@@ -0,0 +1,62 @@
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "active_support/cache"
+
+class CacheStoreWriteMultiEntriesStoreProviderInterfaceTest < ActiveSupport::TestCase
+  setup do
+    @cache = ActiveSupport::Cache.lookup_store(:null_store)
+  end
+
+  test "fetch_multi uses write_multi_entries store provider interface" do
+    assert_called_with(@cache, :write_multi_entries) do
+      @cache.fetch_multi "a", "b", "c" do |key|
+        key * 2
+      end
+    end
+  end
+end
+
+class CacheStoreWriteMultiInstrumentationTest < ActiveSupport::TestCase
+  setup do
+    @cache = ActiveSupport::Cache.lookup_store(:null_store)
+  end
+
+  test "instrumentation" do
+    writes = { "a" => "aa", "b" => "bb" }
+
+    events = with_instrumentation "write_multi" do
+      @cache.write_multi(writes)
+    end
+
+    assert_equal %w[ cache_write_multi.active_support ], events.map(&:name)
+    assert_nil events[0].payload[:super_operation]
+    assert_equal({ "a" => "aa", "b" => "bb" }, events[0].payload[:key])
+  end
+
+  test "instrumentation with fetch_multi as super operation" do
+    skip "fetch_multi isn't instrumented yet"
+
+    events = with_instrumentation "write_multi" do
+      @cache.fetch_multi("a", "b") { |key| key * 2 }
+    end
+
+    assert_equal %w[ cache_write_multi.active_support ], events.map(&:name)
+    assert_nil events[0].payload[:super_operation]
+    assert !events[0].payload[:hit]
+  end
+
+  private
+    def with_instrumentation(method)
+      event_name = "cache_#{method}.active_support"
+
+      [].tap do |events|
+        ActiveSupport::Notifications.subscribe event_name do |*args|
+          events << ActiveSupport::Notifications::Event.new(*args)
+        end
+        yield
+      end
+    ensure
+      ActiveSupport::Notifications.unsubscribe event_name
+    end
+end
diff --git a/activesupport/test/cache/local_cache_middleware_test.rb b/activesupport/test/cache/local_cache_middleware_test.rb
new file mode 100644
index 0000000000..e59fae0b4c
--- /dev/null
+++ b/activesupport/test/cache/local_cache_middleware_test.rb
@@ -0,0 +1,63 @@
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "active_support/cache"
+
+module ActiveSupport
+  module Cache
+    module Strategy
+      module LocalCache
+        class MiddlewareTest < ActiveSupport::TestCase
+          def test_local_cache_cleared_on_close
+            key = "super awesome key"
+            assert_nil LocalCacheRegistry.cache_for key
+            middleware = Middleware.new("<3", key).new(->(env) {
+              assert LocalCacheRegistry.cache_for(key), "should have a cache"
+              [200, {}, []]
+            })
+            _, _, body = middleware.call({})
+            assert LocalCacheRegistry.cache_for(key), "should still have a cache"
+            body.each {}
+            assert LocalCacheRegistry.cache_for(key), "should still have a cache"
+            body.close
+            assert_nil LocalCacheRegistry.cache_for(key)
+          end
+
+          def test_local_cache_cleared_and_response_should_be_present_on_invalid_parameters_error
+            key = "super awesome key"
+            assert_nil LocalCacheRegistry.cache_for key
+            middleware = Middleware.new("<3", key).new(->(env) {
+              assert LocalCacheRegistry.cache_for(key), "should have a cache"
+              raise Rack::Utils::InvalidParameterError
+            })
+            response = middleware.call({})
+            assert response, "response should exist"
+            assert_nil LocalCacheRegistry.cache_for(key)
+          end
+
+          def test_local_cache_cleared_on_exception
+            key = "super awesome key"
+            assert_nil LocalCacheRegistry.cache_for key
+            middleware = Middleware.new("<3", key).new(->(env) {
+              assert LocalCacheRegistry.cache_for(key), "should have a cache"
+              raise
+            })
+            assert_raises(RuntimeError) { middleware.call({}) }
+            assert_nil LocalCacheRegistry.cache_for(key)
+          end
+
+          def test_local_cache_cleared_on_throw
+            key = "super awesome key"
+            assert_nil LocalCacheRegistry.cache_for key
+            middleware = Middleware.new("<3", key).new(->(env) {
+              assert LocalCacheRegistry.cache_for(key), "should have a cache"
+              throw :warden
+            })
+            assert_throws(:warden) { middleware.call({}) }
+            assert_nil LocalCacheRegistry.cache_for(key)
+          end
+        end
+      end
+    end
+  end
+end
diff --git a/activesupport/test/cache/stores/file_store_test.rb b/activesupport/test/cache/stores/file_store_test.rb
new file mode 100644
index 0000000000..66231b0a82
--- /dev/null
+++ b/activesupport/test/cache/stores/file_store_test.rb
@@ -0,0 +1,131 @@
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "active_support/cache"
+require_relative "../behaviors"
+require "pathname"
+
+class FileStoreTest < ActiveSupport::TestCase
+  def setup
+    Dir.mkdir(cache_dir) unless File.exist?(cache_dir)
+    @cache = ActiveSupport::Cache.lookup_store(:file_store, cache_dir, expires_in: 60)
+    @peek = ActiveSupport::Cache.lookup_store(:file_store, cache_dir, expires_in: 60)
+    @cache_with_pathname = ActiveSupport::Cache.lookup_store(:file_store, Pathname.new(cache_dir), expires_in: 60)
+
+    @buffer = StringIO.new
+    @cache.logger = ActiveSupport::Logger.new(@buffer)
+  end
+
+  def teardown
+    FileUtils.rm_r(cache_dir)
+  rescue Errno::ENOENT
+  end
+
+  def cache_dir
+    File.join(Dir.pwd, "tmp_cache")
+  end
+
+  include CacheStoreBehavior
+  include CacheStoreVersionBehavior
+  include LocalCacheBehavior
+  include CacheDeleteMatchedBehavior
+  include CacheIncrementDecrementBehavior
+  include AutoloadingCacheBehavior
+
+  def test_clear
+    gitkeep = File.join(cache_dir, ".gitkeep")
+    keep = File.join(cache_dir, ".keep")
+    FileUtils.touch([gitkeep, keep])
+    @cache.clear
+    assert File.exist?(gitkeep)
+    assert File.exist?(keep)
+  end
+
+  def test_clear_without_cache_dir
+    FileUtils.rm_r(cache_dir)
+    @cache.clear
+  end
+
+  def test_long_uri_encoded_keys
+    @cache.write("%" * 870, 1)
+    assert_equal 1, @cache.read("%" * 870)
+  end
+
+  def test_key_transformation
+    key = @cache.send(:normalize_key, "views/index?id=1", {})
+    assert_equal "views/index?id=1", @cache.send(:file_path_key, key)
+  end
+
+  def test_key_transformation_with_pathname
+    FileUtils.touch(File.join(cache_dir, "foo"))
+    key = @cache_with_pathname.send(:normalize_key, "views/index?id=1", {})
+    assert_equal "views/index?id=1", @cache_with_pathname.send(:file_path_key, key)
+  end
+
+  # Test that generated cache keys are short enough to have Tempfile stuff added to them and
+  # remain valid
+  def test_filename_max_size
+    key = "#{'A' * ActiveSupport::Cache::FileStore::FILENAME_MAX_SIZE}"
+    path = @cache.send(:normalize_key, key, {})
+    Dir::Tmpname.create(path) do |tmpname, n, opts|
+      assert File.basename(tmpname + ".lock").length <= 255, "Temp filename too long: #{File.basename(tmpname + '.lock').length}"
+    end
+  end
+
+  # Because file systems have a maximum filename size, filenames > max size should be split in to directories
+  # If filename is 'AAAAB', where max size is 4, the returned path should be AAAA/B
+  def test_key_transformation_max_filename_size
+    key = "#{'A' * ActiveSupport::Cache::FileStore::FILENAME_MAX_SIZE}B"
+    path = @cache.send(:normalize_key, key, {})
+    assert path.split("/").all? { |dir_name| dir_name.size <= ActiveSupport::Cache::FileStore::FILENAME_MAX_SIZE }
+    assert_equal "B", File.basename(path)
+  end
+
+  # If nothing has been stored in the cache, there is a chance the cache directory does not yet exist
+  # Ensure delete_matched gracefully handles this case
+  def test_delete_matched_when_cache_directory_does_not_exist
+    assert_nothing_raised do
+      ActiveSupport::Cache::FileStore.new("/test/cache/directory").delete_matched(/does_not_exist/)
+    end
+  end
+
+  def test_delete_does_not_delete_empty_parent_dir
+    sub_cache_dir = File.join(cache_dir, "subdir/")
+    sub_cache_store = ActiveSupport::Cache::FileStore.new(sub_cache_dir)
+    assert_nothing_raised do
+      assert sub_cache_store.write("foo", "bar")
+      assert sub_cache_store.delete("foo")
+    end
+    assert File.exist?(cache_dir), "Parent of top level cache dir was deleted!"
+    assert File.exist?(sub_cache_dir), "Top level cache dir was deleted!"
+    assert Dir.entries(sub_cache_dir).reject { |f| ActiveSupport::Cache::FileStore::EXCLUDED_DIRS.include?(f) }.empty?
+  end
+
+  def test_log_exception_when_cache_read_fails
+    File.stub(:exist?, -> { raise StandardError.new("failed") }) do
+      @cache.send(:read_entry, "winston", {})
+      assert @buffer.string.present?
+    end
+  end
+
+  def test_cleanup_removes_all_expired_entries
+    time = Time.now
+    @cache.write("foo", "bar", expires_in: 10)
+    @cache.write("baz", "qux")
+    @cache.write("quux", "corge", expires_in: 20)
+    Time.stub(:now, time + 15) do
+      @cache.cleanup
+      assert_not @cache.exist?("foo")
+      assert @cache.exist?("baz")
+      assert @cache.exist?("quux")
+      assert_equal 2, Dir.glob(File.join(cache_dir, "**")).size
+    end
+  end
+
+  def test_write_with_unless_exist
+    assert_equal true, @cache.write(1, "aaaaaaaaaa")
+    assert_equal false, @cache.write(1, "aaaaaaaaaa", unless_exist: true)
+    @cache.write(1, nil)
+    assert_equal false, @cache.write(1, "aaaaaaaaaa", unless_exist: true)
+  end
+end
diff --git a/activesupport/test/cache/stores/mem_cache_store_test.rb b/activesupport/test/cache/stores/mem_cache_store_test.rb
new file mode 100644
index 0000000000..99624caf8a
--- /dev/null
+++ b/activesupport/test/cache/stores/mem_cache_store_test.rb
@@ -0,0 +1,92 @@
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "active_support/cache"
+require_relative "../behaviors"
+require "dalli"
+
+class MemCacheStoreTest < ActiveSupport::TestCase
+  begin
+    ss = Dalli::Client.new("localhost:11211").stats
+    raise Dalli::DalliError unless ss["localhost:11211"]
+
+    MEMCACHE_UP = true
+  rescue Dalli::DalliError
+    $stderr.puts "Skipping memcached tests. Start memcached and try again."
+    MEMCACHE_UP = false
+  end
+
+  def setup
+    skip "memcache server is not up" unless MEMCACHE_UP
+
+    @cache = ActiveSupport::Cache.lookup_store(:mem_cache_store, expires_in: 60)
+    @peek = ActiveSupport::Cache.lookup_store(:mem_cache_store)
+    @data = @cache.instance_variable_get(:@data)
+    @cache.clear
+    @cache.silence!
+    @cache.logger = ActiveSupport::Logger.new(File::NULL)
+  end
+
+  include CacheStoreBehavior
+  include CacheStoreVersionBehavior
+  include LocalCacheBehavior
+  include CacheIncrementDecrementBehavior
+  include EncodedKeyCacheBehavior
+  include AutoloadingCacheBehavior
+
+  def test_raw_values
+    cache = ActiveSupport::Cache.lookup_store(:mem_cache_store, raw: true)
+    cache.clear
+    cache.write("foo", 2)
+    assert_equal "2", cache.read("foo")
+  end
+
+  def test_raw_values_with_marshal
+    cache = ActiveSupport::Cache.lookup_store(:mem_cache_store, raw: true)
+    cache.clear
+    cache.write("foo", Marshal.dump([]))
+    assert_equal [], cache.read("foo")
+  end
+
+  def test_local_cache_raw_values
+    cache = ActiveSupport::Cache.lookup_store(:mem_cache_store, raw: true)
+    cache.clear
+    cache.with_local_cache do
+      cache.write("foo", 2)
+      assert_equal "2", cache.read("foo")
+    end
+  end
+
+  def test_increment_expires_in
+    cache = ActiveSupport::Cache.lookup_store(:mem_cache_store, raw: true)
+    cache.clear
+    assert_called_with cache.instance_variable_get(:@data), :incr, [ "foo", 1, 60 ] do
+      cache.increment("foo", 1, expires_in: 60)
+    end
+  end
+
+  def test_decrement_expires_in
+    cache = ActiveSupport::Cache.lookup_store(:mem_cache_store, raw: true)
+    cache.clear
+    assert_called_with cache.instance_variable_get(:@data), :decr, [ "foo", 1, 60 ] do
+      cache.decrement("foo", 1, expires_in: 60)
+    end
+  end
+
+  def test_local_cache_raw_values_with_marshal
+    cache = ActiveSupport::Cache.lookup_store(:mem_cache_store, raw: true)
+    cache.clear
+    cache.with_local_cache do
+      cache.write("foo", Marshal.dump([]))
+      assert_equal [], cache.read("foo")
+    end
+  end
+
+  def test_read_should_return_a_different_object_id_each_time_it_is_called
+    @cache.write("foo", "bar")
+    value = @cache.read("foo")
+    assert_not_equal value.object_id, @cache.read("foo").object_id
+    value << "bingo"
+    assert_not_equal value, @cache.read("foo")
+  end
+end
diff --git a/activesupport/test/cache/stores/memory_store_test.rb b/activesupport/test/cache/stores/memory_store_test.rb
new file mode 100644
index 0000000000..3981f05331
--- /dev/null
+++ b/activesupport/test/cache/stores/memory_store_test.rb
@@ -0,0 +1,109 @@
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "active_support/cache"
+require_relative "../behaviors"
+
+class MemoryStoreTest < ActiveSupport::TestCase
+  def setup
+    @record_size = ActiveSupport::Cache.lookup_store(:memory_store).send(:cached_size, 1, ActiveSupport::Cache::Entry.new("aaaaaaaaaa"))
+    @cache = ActiveSupport::Cache.lookup_store(:memory_store, expires_in: 60, size: @record_size * 10 + 1)
+  end
+
+  include CacheStoreBehavior
+  include CacheStoreVersionBehavior
+  include CacheDeleteMatchedBehavior
+  include CacheIncrementDecrementBehavior
+
+  def test_prune_size
+    @cache.write(1, "aaaaaaaaaa") && sleep(0.001)
+    @cache.write(2, "bbbbbbbbbb") && sleep(0.001)
+    @cache.write(3, "cccccccccc") && sleep(0.001)
+    @cache.write(4, "dddddddddd") && sleep(0.001)
+    @cache.write(5, "eeeeeeeeee") && sleep(0.001)
+    @cache.read(2) && sleep(0.001)
+    @cache.read(4)
+    @cache.prune(@record_size * 3)
+    assert @cache.exist?(5)
+    assert @cache.exist?(4)
+    assert !@cache.exist?(3), "no entry"
+    assert @cache.exist?(2)
+    assert !@cache.exist?(1), "no entry"
+  end
+
+  def test_prune_size_on_write
+    @cache.write(1, "aaaaaaaaaa") && sleep(0.001)
+    @cache.write(2, "bbbbbbbbbb") && sleep(0.001)
+    @cache.write(3, "cccccccccc") && sleep(0.001)
+    @cache.write(4, "dddddddddd") && sleep(0.001)
+    @cache.write(5, "eeeeeeeeee") && sleep(0.001)
+    @cache.write(6, "ffffffffff") && sleep(0.001)
+    @cache.write(7, "gggggggggg") && sleep(0.001)
+    @cache.write(8, "hhhhhhhhhh") && sleep(0.001)
+    @cache.write(9, "iiiiiiiiii") && sleep(0.001)
+    @cache.write(10, "kkkkkkkkkk") && sleep(0.001)
+    @cache.read(2) && sleep(0.001)
+    @cache.read(4) && sleep(0.001)
+    @cache.write(11, "llllllllll")
+    assert @cache.exist?(11)
+    assert @cache.exist?(10)
+    assert @cache.exist?(9)
+    assert @cache.exist?(8)
+    assert @cache.exist?(7)
+    assert !@cache.exist?(6), "no entry"
+    assert !@cache.exist?(5), "no entry"
+    assert @cache.exist?(4)
+    assert !@cache.exist?(3), "no entry"
+    assert @cache.exist?(2)
+    assert !@cache.exist?(1), "no entry"
+  end
+
+  def test_prune_size_on_write_based_on_key_length
+    @cache.write(1, "aaaaaaaaaa") && sleep(0.001)
+    @cache.write(2, "bbbbbbbbbb") && sleep(0.001)
+    @cache.write(3, "cccccccccc") && sleep(0.001)
+    @cache.write(4, "dddddddddd") && sleep(0.001)
+    @cache.write(5, "eeeeeeeeee") && sleep(0.001)
+    @cache.write(6, "ffffffffff") && sleep(0.001)
+    @cache.write(7, "gggggggggg") && sleep(0.001)
+    @cache.write(8, "hhhhhhhhhh") && sleep(0.001)
+    @cache.write(9, "iiiiiiiiii") && sleep(0.001)
+    long_key = "*" * 2 * @record_size
+    @cache.write(long_key, "llllllllll")
+    assert @cache.exist?(long_key)
+    assert @cache.exist?(9)
+    assert @cache.exist?(8)
+    assert @cache.exist?(7)
+    assert @cache.exist?(6)
+    assert !@cache.exist?(5), "no entry"
+    assert !@cache.exist?(4), "no entry"
+    assert !@cache.exist?(3), "no entry"
+    assert !@cache.exist?(2), "no entry"
+    assert !@cache.exist?(1), "no entry"
+  end
+
+  def test_pruning_is_capped_at_a_max_time
+    def @cache.delete_entry(*args)
+      sleep(0.01)
+      super
+    end
+    @cache.write(1, "aaaaaaaaaa") && sleep(0.001)
+    @cache.write(2, "bbbbbbbbbb") && sleep(0.001)
+    @cache.write(3, "cccccccccc") && sleep(0.001)
+    @cache.write(4, "dddddddddd") && sleep(0.001)
+    @cache.write(5, "eeeeeeeeee") && sleep(0.001)
+    @cache.prune(30, 0.001)
+    assert @cache.exist?(5)
+    assert @cache.exist?(4)
+    assert @cache.exist?(3)
+    assert @cache.exist?(2)
+    assert !@cache.exist?(1)
+  end
+
+  def test_write_with_unless_exist
+    assert_equal true, @cache.write(1, "aaaaaaaaaa")
+    assert_equal false, @cache.write(1, "aaaaaaaaaa", unless_exist: true)
+    @cache.write(1, nil)
+    assert_equal false, @cache.write(1, "aaaaaaaaaa", unless_exist: true)
+  end
+end
diff --git a/activesupport/test/cache/stores/null_store_test.rb b/activesupport/test/cache/stores/null_store_test.rb
new file mode 100644
index 0000000000..a891cbffc8
--- /dev/null
+++ b/activesupport/test/cache/stores/null_store_test.rb
@@ -0,0 +1,59 @@
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "active_support/cache"
+require_relative "../behaviors"
+
+class NullStoreTest < ActiveSupport::TestCase
+  def setup
+    @cache = ActiveSupport::Cache.lookup_store(:null_store)
+  end
+
+  def test_clear
+    @cache.clear
+  end
+
+  def test_cleanup
+    @cache.cleanup
+  end
+
+  def test_write
+    assert_equal true, @cache.write("name", "value")
+  end
+
+  def test_read
+    @cache.write("name", "value")
+    assert_nil @cache.read("name")
+  end
+
+  def test_delete
+    @cache.write("name", "value")
+    assert_equal false, @cache.delete("name")
+  end
+
+  def test_increment
+    @cache.write("name", 1, raw: true)
+    assert_nil @cache.increment("name")
+  end
+
+  def test_decrement
+    @cache.write("name", 1, raw: true)
+    assert_nil @cache.increment("name")
+  end
+
+  def test_delete_matched
+    @cache.write("name", "value")
+    @cache.delete_matched(/name/)
+  end
+
+  def test_local_store_strategy
+    @cache.with_local_cache do
+      @cache.write("name", "value")
+      assert_equal "value", @cache.read("name")
+      @cache.delete("name")
+      assert_nil @cache.read("name")
+      @cache.write("name", "value")
+    end
+    assert_nil @cache.read("name")
+  end
+end
diff --git a/activesupport/test/cache/stores/redis_cache_store_test.rb b/activesupport/test/cache/stores/redis_cache_store_test.rb
new file mode 100644
index 0000000000..7f684f7a0f
--- /dev/null
+++ b/activesupport/test/cache/stores/redis_cache_store_test.rb
@@ -0,0 +1,151 @@
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "active_support/cache"
+require "active_support/cache/redis_cache_store"
+require_relative "../behaviors"
+
+module ActiveSupport::Cache::RedisCacheStoreTests
+  class LookupTest < ActiveSupport::TestCase
+    test "may be looked up as :redis_cache_store" do
+      assert_kind_of ActiveSupport::Cache::RedisCacheStore,
+        ActiveSupport::Cache.lookup_store(:redis_cache_store)
+    end
+  end
+
+  class InitializationTest < ActiveSupport::TestCase
+    test "omitted URL uses Redis client with default settings" do
+      assert_called_with Redis, :new, [
+        url: nil,
+        connect_timeout: 20, read_timeout: 1, write_timeout: 1,
+        reconnect_attempts: 0,
+      ] do
+        build
+      end
+    end
+
+    test "no URLs uses Redis client with default settings" do
+      assert_called_with Redis, :new, [
+        url: nil,
+        connect_timeout: 20, read_timeout: 1, write_timeout: 1,
+        reconnect_attempts: 0,
+      ] do
+        build url: []
+      end
+    end
+
+    test "singular URL uses Redis client" do
+      assert_called_with Redis, :new, [
+        url: "redis://localhost:6379/0",
+        connect_timeout: 20, read_timeout: 1, write_timeout: 1,
+        reconnect_attempts: 0,
+      ] do
+        build url: "redis://localhost:6379/0"
+      end
+    end
+
+    test "one URL uses Redis client" do
+      assert_called_with Redis, :new, [
+        url: "redis://localhost:6379/0",
+        connect_timeout: 20, read_timeout: 1, write_timeout: 1,
+        reconnect_attempts: 0,
+      ] do
+        build url: %w[ redis://localhost:6379/0 ]
+      end
+    end
+
+    test "multiple URLs uses Redis::Distributed client" do
+      assert_called_with Redis, :new, [
+        [ url: "redis://localhost:6379/0",
+          connect_timeout: 20, read_timeout: 1, write_timeout: 1,
+          reconnect_attempts: 0 ],
+        [ url: "redis://localhost:6379/1",
+          connect_timeout: 20, read_timeout: 1, write_timeout: 1,
+          reconnect_attempts: 0 ],
+      ], returns: Redis.new do
+        @cache = build url: %w[ redis://localhost:6379/0 redis://localhost:6379/1 ]
+        assert_kind_of ::Redis::Distributed, @cache.redis
+      end
+    end
+
+    test "block argument uses yielded client" do
+      block = -> { :custom_redis_client }
+      assert_called block, :call do
+        build redis: block
+      end
+    end
+
+    private
+      def build(**kwargs)
+        ActiveSupport::Cache::RedisCacheStore.new(**kwargs).tap do |cache|
+          cache.redis
+        end
+      end
+  end
+
+  class StoreTest < ActiveSupport::TestCase
+    setup do
+      @namespace = "namespace"
+
+      @cache = ActiveSupport::Cache::RedisCacheStore.new(timeout: 0.1, namespace: @namespace, expires_in: 60)
+      # @cache.logger = Logger.new($stdout)  # For test debugging
+
+      # For LocalCacheBehavior tests
+      @peek = ActiveSupport::Cache::RedisCacheStore.new(timeout: 0.1, namespace: @namespace)
+    end
+
+    teardown do
+      @cache.clear
+      @cache.redis.disconnect!
+    end
+  end
+
+  class RedisCacheStoreCommonBehaviorTest < StoreTest
+    include CacheStoreBehavior
+    include CacheStoreVersionBehavior
+    include LocalCacheBehavior
+    include CacheIncrementDecrementBehavior
+    include AutoloadingCacheBehavior
+  end
+
+  # Separate test class so we can omit the namespace which causes expected,
+  # appropriate complaints about incompatible string encodings.
+  class KeyEncodingSafetyTest < StoreTest
+    include EncodedKeyCacheBehavior
+
+    setup do
+      @cache = ActiveSupport::Cache::RedisCacheStore.new(timeout: 0.1)
+      @cache.logger = nil
+    end
+  end
+
+  class StoreAPITest < StoreTest
+  end
+
+  class FailureSafetyTest < StoreTest
+    test "fetch read failure returns nil" do
+    end
+
+    test "fetch read failure does not attempt to write" do
+    end
+
+    test "write failure returns nil" do
+    end
+  end
+
+  class DeleteMatchedTest < StoreTest
+    test "deletes keys matching glob" do
+      @cache.write("foo", "bar")
+      @cache.write("fu", "baz")
+      @cache.delete_matched("foo*")
+      assert !@cache.exist?("foo")
+      assert @cache.exist?("fu")
+    end
+
+    test "fails with regexp matchers" do
+      assert_raise ArgumentError do
+        @cache.delete_matched(/OO/i)
+      end
+    end
+  end
+end
diff --git a/activesupport/test/caching_test.rb b/activesupport/test/caching_test.rb
deleted file mode 100644
index ec7d028d7e..0000000000
--- a/activesupport/test/caching_test.rb
+++ /dev/null
@@ -1,1194 +0,0 @@
-require 'logger'
-require 'abstract_unit'
-require 'active_support/cache'
-require 'dependencies_test_helpers'
-
-module ActiveSupport
-  module Cache
-    module Strategy
-      module LocalCache
-        class MiddlewareTest < ActiveSupport::TestCase
-          def test_local_cache_cleared_on_close
-            key = "super awesome key"
-            assert_nil LocalCacheRegistry.cache_for key
-            middleware = Middleware.new('<3', key).new(->(env) {
-              assert LocalCacheRegistry.cache_for(key), 'should have a cache'
-              [200, {}, []]
-            })
-            _, _, body = middleware.call({})
-            assert LocalCacheRegistry.cache_for(key), 'should still have a cache'
-            body.each { }
-            assert LocalCacheRegistry.cache_for(key), 'should still have a cache'
-            body.close
-            assert_nil LocalCacheRegistry.cache_for(key)
-          end
-
-          def test_local_cache_cleared_on_exception
-            key = "super awesome key"
-            assert_nil LocalCacheRegistry.cache_for key
-            middleware = Middleware.new('<3', key).new(->(env) {
-              assert LocalCacheRegistry.cache_for(key), 'should have a cache'
-              raise
-            })
-            assert_raises(RuntimeError) { middleware.call({}) }
-            assert_nil LocalCacheRegistry.cache_for(key)
-          end
-        end
-      end
-    end
-  end
-end
-
-class CacheKeyTest < ActiveSupport::TestCase
-  def test_entry_legacy_optional_ivars
-    legacy = Class.new(ActiveSupport::Cache::Entry) do
-      def initialize(value, options = {})
-        @value = value
-        @expires_in = nil
-        @created_at = nil
-        super
-      end
-    end
-
-    entry = legacy.new 'foo'
-    assert_equal 'foo', entry.value
-  end
-
-  def test_expand_cache_key
-    assert_equal '1/2/true', ActiveSupport::Cache.expand_cache_key([1, '2', true])
-    assert_equal 'name/1/2/true', ActiveSupport::Cache.expand_cache_key([1, '2', true], :name)
-  end
-
-  def test_expand_cache_key_with_rails_cache_id
-    with_env('RAILS_CACHE_ID' => 'c99') do
-      assert_equal 'c99/foo', ActiveSupport::Cache.expand_cache_key(:foo)
-      assert_equal 'c99/foo', ActiveSupport::Cache.expand_cache_key([:foo])
-      assert_equal 'c99/foo/bar', ActiveSupport::Cache.expand_cache_key([:foo, :bar])
-      assert_equal 'nm/c99/foo', ActiveSupport::Cache.expand_cache_key(:foo, :nm)
-      assert_equal 'nm/c99/foo', ActiveSupport::Cache.expand_cache_key([:foo], :nm)
-      assert_equal 'nm/c99/foo/bar', ActiveSupport::Cache.expand_cache_key([:foo, :bar], :nm)
-    end
-  end
-
-  def test_expand_cache_key_with_rails_app_version
-    with_env('RAILS_APP_VERSION' => 'rails3') do
-      assert_equal 'rails3/foo', ActiveSupport::Cache.expand_cache_key(:foo)
-    end
-  end
-
-  def test_expand_cache_key_rails_cache_id_should_win_over_rails_app_version
-    with_env('RAILS_CACHE_ID' => 'c99', 'RAILS_APP_VERSION' => 'rails3') do
-      assert_equal 'c99/foo', ActiveSupport::Cache.expand_cache_key(:foo)
-    end
-  end
-
-  def test_expand_cache_key_respond_to_cache_key
-    key = 'foo'
-    def key.cache_key
-      :foo_key
-    end
-    assert_equal 'foo_key', ActiveSupport::Cache.expand_cache_key(key)
-  end
-
-  def test_expand_cache_key_array_with_something_that_responds_to_cache_key
-    key = 'foo'
-    def key.cache_key
-      :foo_key
-    end
-    assert_equal 'foo_key', ActiveSupport::Cache.expand_cache_key([key])
-  end
-
-  def test_expand_cache_key_of_nil
-    assert_equal '', ActiveSupport::Cache.expand_cache_key(nil)
-  end
-
-  def test_expand_cache_key_of_false
-    assert_equal 'false', ActiveSupport::Cache.expand_cache_key(false)
-  end
-
-  def test_expand_cache_key_of_true
-    assert_equal 'true', ActiveSupport::Cache.expand_cache_key(true)
-  end
-
-  def test_expand_cache_key_of_array_like_object
-    assert_equal 'foo/bar/baz', ActiveSupport::Cache.expand_cache_key(%w{foo bar baz}.to_enum)
-  end
-
-  private
-
-  def with_env(kv)
-    old_values = {}
-    kv.each { |key, value| old_values[key], ENV[key] = ENV[key], value }
-    yield
-  ensure
-    old_values.each { |key, value| ENV[key] = value}
-  end
-end
-
-class CacheStoreSettingTest < ActiveSupport::TestCase
-  def test_file_fragment_cache_store
-    store = ActiveSupport::Cache.lookup_store :file_store, "/path/to/cache/directory"
-    assert_kind_of(ActiveSupport::Cache::FileStore, store)
-    assert_equal "/path/to/cache/directory", store.cache_path
-  end
-
-  def test_mem_cache_fragment_cache_store
-    assert_called_with(Dalli::Client, :new, [%w[localhost], {}]) do
-      store = ActiveSupport::Cache.lookup_store :mem_cache_store, "localhost"
-      assert_kind_of(ActiveSupport::Cache::MemCacheStore, store)
-    end
-  end
-
-  def test_mem_cache_fragment_cache_store_with_given_mem_cache
-    mem_cache = Dalli::Client.new
-    assert_not_called(Dalli::Client, :new) do
-      store = ActiveSupport::Cache.lookup_store :mem_cache_store, mem_cache
-      assert_kind_of(ActiveSupport::Cache::MemCacheStore, store)
-    end
-  end
-
-  def test_mem_cache_fragment_cache_store_with_not_dalli_client
-    assert_not_called(Dalli::Client, :new) do
-      memcache = Object.new
-      assert_raises(ArgumentError) do
-        ActiveSupport::Cache.lookup_store :mem_cache_store, memcache
-      end
-    end
-  end
-
-  def test_mem_cache_fragment_cache_store_with_multiple_servers
-    assert_called_with(Dalli::Client, :new, [%w[localhost 192.168.1.1], {}]) do
-      store = ActiveSupport::Cache.lookup_store :mem_cache_store, "localhost", '192.168.1.1'
-      assert_kind_of(ActiveSupport::Cache::MemCacheStore, store)
-    end
-  end
-
-  def test_mem_cache_fragment_cache_store_with_options
-    assert_called_with(Dalli::Client, :new, [%w[localhost 192.168.1.1], { :timeout => 10 }]) do
-      store = ActiveSupport::Cache.lookup_store :mem_cache_store, "localhost", '192.168.1.1', :namespace => 'foo', :timeout => 10
-      assert_kind_of(ActiveSupport::Cache::MemCacheStore, store)
-      assert_equal 'foo', store.options[:namespace]
-    end
-  end
-
-  def test_object_assigned_fragment_cache_store
-    store = ActiveSupport::Cache.lookup_store ActiveSupport::Cache::FileStore.new("/path/to/cache/directory")
-    assert_kind_of(ActiveSupport::Cache::FileStore, store)
-    assert_equal "/path/to/cache/directory", store.cache_path
-  end
-end
-
-class CacheStoreNamespaceTest < ActiveSupport::TestCase
-  def test_static_namespace
-    cache = ActiveSupport::Cache.lookup_store(:memory_store, :namespace => "tester")
-    cache.write("foo", "bar")
-    assert_equal "bar", cache.read("foo")
-    assert_equal "bar", cache.instance_variable_get(:@data)["tester:foo"].value
-  end
-
-  def test_proc_namespace
-    test_val = "tester"
-    proc = lambda{test_val}
-    cache = ActiveSupport::Cache.lookup_store(:memory_store, :namespace => proc)
-    cache.write("foo", "bar")
-    assert_equal "bar", cache.read("foo")
-    assert_equal "bar", cache.instance_variable_get(:@data)["tester:foo"].value
-  end
-
-  def test_delete_matched_key_start
-    cache = ActiveSupport::Cache.lookup_store(:memory_store, :namespace => "tester")
-    cache.write("foo", "bar")
-    cache.write("fu", "baz")
-    cache.delete_matched(/^fo/)
-    assert !cache.exist?("foo")
-    assert cache.exist?("fu")
-  end
-
-  def test_delete_matched_key
-    cache = ActiveSupport::Cache.lookup_store(:memory_store, :namespace => "foo")
-    cache.write("foo", "bar")
-    cache.write("fu", "baz")
-    cache.delete_matched(/OO/i)
-    assert !cache.exist?("foo")
-    assert cache.exist?("fu")
-  end
-end
-
-# Tests the base functionality that should be identical across all cache stores.
-module CacheStoreBehavior
-  def test_should_read_and_write_strings
-    assert @cache.write('foo', 'bar')
-    assert_equal 'bar', @cache.read('foo')
-  end
-
-  def test_should_overwrite
-    @cache.write('foo', 'bar')
-    @cache.write('foo', 'baz')
-    assert_equal 'baz', @cache.read('foo')
-  end
-
-  def test_fetch_without_cache_miss
-    @cache.write('foo', 'bar')
-    assert_not_called(@cache, :write) do
-      assert_equal 'bar', @cache.fetch('foo') { 'baz' }
-    end
-  end
-
-  def test_fetch_with_cache_miss
-    assert_called_with(@cache, :write, ['foo', 'baz', @cache.options]) do
-      assert_equal 'baz', @cache.fetch('foo') { 'baz' }
-    end
-  end
-
-  def test_fetch_with_cache_miss_passes_key_to_block
-    cache_miss = false
-    assert_equal 3, @cache.fetch('foo') { |key| cache_miss = true; key.length }
-    assert cache_miss
-
-    cache_miss = false
-    assert_equal 3, @cache.fetch('foo') { |key| cache_miss = true; key.length }
-    assert !cache_miss
-  end
-
-  def test_fetch_with_forced_cache_miss
-    @cache.write('foo', 'bar')
-    assert_not_called(@cache, :read) do
-      assert_called_with(@cache, :write, ['foo', 'bar', @cache.options.merge(:force => true)]) do
-        @cache.fetch('foo', :force => true) { 'bar' }
-      end
-    end
-  end
-
-  def test_fetch_with_cached_nil
-    @cache.write('foo', nil)
-    assert_not_called(@cache, :write) do
-      assert_nil @cache.fetch('foo') { 'baz' }
-    end
-  end
-
-  def test_fetch_with_forced_cache_miss_with_block
-    @cache.write('foo', 'bar')
-    assert_equal 'foo_bar', @cache.fetch('foo', force: true) { 'foo_bar' }
-  end
-
-  def test_fetch_with_forced_cache_miss_without_block
-    @cache.write('foo', 'bar')
-    assert_raises(ArgumentError) do
-      @cache.fetch('foo', force: true)
-    end
-
-    assert_equal 'bar', @cache.read('foo')
-  end
-
-  def test_should_read_and_write_hash
-    assert @cache.write('foo', {:a => "b"})
-    assert_equal({:a => "b"}, @cache.read('foo'))
-  end
-
-  def test_should_read_and_write_integer
-    assert @cache.write('foo', 1)
-    assert_equal 1, @cache.read('foo')
-  end
-
-  def test_should_read_and_write_nil
-    assert @cache.write('foo', nil)
-    assert_equal nil, @cache.read('foo')
-  end
-
-  def test_should_read_and_write_false
-    assert @cache.write('foo', false)
-    assert_equal false, @cache.read('foo')
-  end
-
-  def test_read_multi
-    @cache.write('foo', 'bar')
-    @cache.write('fu', 'baz')
-    @cache.write('fud', 'biz')
-    assert_equal({"foo" => "bar", "fu" => "baz"}, @cache.read_multi('foo', 'fu'))
-  end
-
-  def test_read_multi_with_expires
-    time = Time.now
-    @cache.write('foo', 'bar', :expires_in => 10)
-    @cache.write('fu', 'baz')
-    @cache.write('fud', 'biz')
-    Time.stub(:now, time + 11) do
-      assert_equal({"fu" => "baz"}, @cache.read_multi('foo', 'fu'))
-    end
-  end
-
-  def test_fetch_multi
-    @cache.write('foo', 'bar')
-    @cache.write('fud', 'biz')
-
-    values = @cache.fetch_multi('foo', 'fu', 'fud') { |value| value * 2 }
-
-    assert_equal({ 'foo' => 'bar', 'fu' => 'fufu', 'fud' => 'biz' }, values)
-    assert_equal('fufu', @cache.read('fu'))
-  end
-
-  def test_multi_with_objects
-    cache_struct = Struct.new(:cache_key, :title)
-    foo = cache_struct.new('foo', 'FOO!')
-    bar = cache_struct.new('bar')
-
-    @cache.write('bar', 'BAM!')
-
-    values = @cache.fetch_multi(foo, bar) { |object| object.title }
-
-    assert_equal({ foo => 'FOO!', bar => 'BAM!' }, values)
-  end
-
-  def test_read_and_write_compressed_small_data
-    @cache.write('foo', 'bar', :compress => true)
-    assert_equal 'bar', @cache.read('foo')
-  end
-
-  def test_read_and_write_compressed_large_data
-    @cache.write('foo', 'bar', :compress => true, :compress_threshold => 2)
-    assert_equal 'bar', @cache.read('foo')
-  end
-
-  def test_read_and_write_compressed_nil
-    @cache.write('foo', nil, :compress => true)
-    assert_nil @cache.read('foo')
-  end
-
-  def test_cache_key
-    obj = Object.new
-    def obj.cache_key
-      :foo
-    end
-    @cache.write(obj, "bar")
-    assert_equal "bar", @cache.read("foo")
-  end
-
-  def test_param_as_cache_key
-    obj = Object.new
-    def obj.to_param
-      "foo"
-    end
-    @cache.write(obj, "bar")
-    assert_equal "bar", @cache.read("foo")
-  end
-
-  def test_array_as_cache_key
-    @cache.write([:fu, "foo"], "bar")
-    assert_equal "bar", @cache.read("fu/foo")
-  end
-
-  def test_hash_as_cache_key
-    @cache.write({:foo => 1, :fu => 2}, "bar")
-    assert_equal "bar", @cache.read("foo=1/fu=2")
-  end
-
-  def test_keys_are_case_sensitive
-    @cache.write("foo", "bar")
-    assert_nil @cache.read("FOO")
-  end
-
-  def test_exist
-    @cache.write('foo', 'bar')
-    assert_equal true, @cache.exist?('foo')
-    assert_equal false, @cache.exist?('bar')
-  end
-
-  def test_nil_exist
-    @cache.write('foo', nil)
-    assert @cache.exist?('foo')
-  end
-
-  def test_delete
-    @cache.write('foo', 'bar')
-    assert @cache.exist?('foo')
-    assert @cache.delete('foo')
-    assert !@cache.exist?('foo')
-  end
-
-  def test_original_store_objects_should_not_be_immutable
-    bar = 'bar'
-    @cache.write('foo', bar)
-    assert_nothing_raised { bar.gsub!(/.*/, 'baz') }
-  end
-
-  def test_expires_in
-    time = Time.local(2008, 4, 24)
-
-    Time.stub(:now, time) do
-      @cache.write('foo', 'bar')
-      assert_equal 'bar', @cache.read('foo')
-    end
-
-    Time.stub(:now, time + 30) do
-      assert_equal 'bar', @cache.read('foo')
-    end
-
-    Time.stub(:now, time + 61) do
-      assert_nil @cache.read('foo')
-    end
-  end
-
-  def test_race_condition_protection_skipped_if_not_defined
-    @cache.write('foo', 'bar')
-    time = @cache.send(:read_entry, @cache.send(:normalize_key, 'foo', {}), {}).expires_at
-
-    Time.stub(:now, Time.at(time)) do
-      result = @cache.fetch('foo') do
-        assert_equal nil, @cache.read('foo')
-        'baz'
-      end
-      assert_equal 'baz', result
-    end
-  end
-
-  def test_race_condition_protection_is_limited
-    time = Time.now
-    @cache.write('foo', 'bar', :expires_in => 60)
-    Time.stub(:now, time + 71) do
-      result = @cache.fetch('foo', :race_condition_ttl => 10) do
-        assert_equal nil, @cache.read('foo')
-        "baz"
-      end
-      assert_equal "baz", result
-    end
-  end
-
-  def test_race_condition_protection_is_safe
-    time = Time.now
-    @cache.write('foo', 'bar', :expires_in => 60)
-    Time.stub(:now, time + 61) do
-      begin
-        @cache.fetch('foo', :race_condition_ttl => 10) do
-          assert_equal 'bar', @cache.read('foo')
-          raise ArgumentError.new
-        end
-      rescue ArgumentError
-      end
-      assert_equal "bar", @cache.read('foo')
-    end
-    Time.stub(:now, time + 91) do
-      assert_nil @cache.read('foo')
-    end
-  end
-
-  def test_race_condition_protection
-    time = Time.now
-    @cache.write('foo', 'bar', :expires_in => 60)
-    Time.stub(:now, time + 61) do
-      result = @cache.fetch('foo', :race_condition_ttl => 10) do
-        assert_equal 'bar', @cache.read('foo')
-        "baz"
-      end
-      assert_equal "baz", result
-    end
-  end
-
-  def test_crazy_key_characters
-    crazy_key = "#/:*(<+=> )&$%@?;'\"\'`~-"
-    assert @cache.write(crazy_key, "1", :raw => true)
-    assert_equal "1", @cache.read(crazy_key)
-    assert_equal "1", @cache.fetch(crazy_key)
-    assert @cache.delete(crazy_key)
-    assert_equal "2", @cache.fetch(crazy_key, :raw => true) { "2" }
-    assert_equal 3, @cache.increment(crazy_key)
-    assert_equal 2, @cache.decrement(crazy_key)
-  end
-
-  def test_really_long_keys
-    key = ""
-    900.times{key << "x"}
-    assert @cache.write(key, "bar")
-    assert_equal "bar", @cache.read(key)
-    assert_equal "bar", @cache.fetch(key)
-    assert_nil @cache.read("#{key}x")
-    assert_equal({key => "bar"}, @cache.read_multi(key))
-    assert @cache.delete(key)
-  end
-
-  def test_cache_hit_instrumentation
-    key = "test_key"
-    @events = []
-    ActiveSupport::Notifications.subscribe "cache_read.active_support" do |*args|
-      @events << ActiveSupport::Notifications::Event.new(*args)
-    end
-    assert @cache.write(key, "1", :raw => true)
-    assert @cache.fetch(key) {}
-    assert_equal 1, @events.length
-    assert_equal 'cache_read.active_support', @events[0].name
-    assert_equal :fetch, @events[0].payload[:super_operation]
-    assert @events[0].payload[:hit]
-  ensure
-    ActiveSupport::Notifications.unsubscribe "cache_read.active_support"
-  end
-
-  def test_cache_miss_instrumentation
-    @events = []
-    ActiveSupport::Notifications.subscribe(/^cache_(.*)\.active_support$/) do |*args|
-      @events << ActiveSupport::Notifications::Event.new(*args)
-    end
-    assert_not @cache.fetch("bad_key") {}
-    assert_equal 3, @events.length
-    assert_equal 'cache_read.active_support', @events[0].name
-    assert_equal 'cache_generate.active_support', @events[1].name
-    assert_equal 'cache_write.active_support', @events[2].name
-    assert_equal :fetch, @events[0].payload[:super_operation]
-    assert_not @events[0].payload[:hit]
-  ensure
-    ActiveSupport::Notifications.unsubscribe "cache_read.active_support"
-  end
-
-  def test_can_call_deprecated_namesaced_key
-    assert_deprecated "`namespaced_key` is deprecated" do
-      @cache.send(:namespaced_key, 111, {})
-    end
-  end
-end
-
-# https://rails.lighthouseapp.com/projects/8994/tickets/6225-memcachestore-cant-deal-with-umlauts-and-special-characters
-# The error is caused by character encodings that can't be compared with ASCII-8BIT regular expressions and by special
-# characters like the umlaut in UTF-8.
-module EncodedKeyCacheBehavior
-  Encoding.list.each do |encoding|
-    define_method "test_#{encoding.name.underscore}_encoded_values" do
-      key = "foo".force_encoding(encoding)
-      assert @cache.write(key, "1", :raw => true)
-      assert_equal "1", @cache.read(key)
-      assert_equal "1", @cache.fetch(key)
-      assert @cache.delete(key)
-      assert_equal "2", @cache.fetch(key, :raw => true) { "2" }
-      assert_equal 3, @cache.increment(key)
-      assert_equal 2, @cache.decrement(key)
-    end
-  end
-
-  def test_common_utf8_values
-    key = "\xC3\xBCmlaut".force_encoding(Encoding::UTF_8)
-    assert @cache.write(key, "1", :raw => true)
-    assert_equal "1", @cache.read(key)
-    assert_equal "1", @cache.fetch(key)
-    assert @cache.delete(key)
-    assert_equal "2", @cache.fetch(key, :raw => true) { "2" }
-    assert_equal 3, @cache.increment(key)
-    assert_equal 2, @cache.decrement(key)
-  end
-
-  def test_retains_encoding
-    key = "\xC3\xBCmlaut".force_encoding(Encoding::UTF_8)
-    assert @cache.write(key, "1", :raw => true)
-    assert_equal Encoding::UTF_8, key.encoding
-  end
-end
-
-module CacheDeleteMatchedBehavior
-  def test_delete_matched
-    @cache.write("foo", "bar")
-    @cache.write("fu", "baz")
-    @cache.write("foo/bar", "baz")
-    @cache.write("fu/baz", "bar")
-    @cache.delete_matched(/oo/)
-    assert !@cache.exist?("foo")
-    assert @cache.exist?("fu")
-    assert !@cache.exist?("foo/bar")
-    assert @cache.exist?("fu/baz")
-  end
-end
-
-module CacheIncrementDecrementBehavior
-  def test_increment
-    @cache.write('foo', 1, :raw => true)
-    assert_equal 1, @cache.read('foo').to_i
-    assert_equal 2, @cache.increment('foo')
-    assert_equal 2, @cache.read('foo').to_i
-    assert_equal 3, @cache.increment('foo')
-    assert_equal 3, @cache.read('foo').to_i
-    assert_nil @cache.increment('bar')
-  end
-
-  def test_decrement
-    @cache.write('foo', 3, :raw => true)
-    assert_equal 3, @cache.read('foo').to_i
-    assert_equal 2, @cache.decrement('foo')
-    assert_equal 2, @cache.read('foo').to_i
-    assert_equal 1, @cache.decrement('foo')
-    assert_equal 1, @cache.read('foo').to_i
-    assert_nil @cache.decrement('bar')
-  end
-end
-
-module LocalCacheBehavior
-  def test_local_writes_are_persistent_on_the_remote_cache
-    retval = @cache.with_local_cache do
-      @cache.write('foo', 'bar')
-    end
-    assert retval
-    assert_equal 'bar', @cache.read('foo')
-  end
-
-  def test_clear_also_clears_local_cache
-    @cache.with_local_cache do
-      @cache.write('foo', 'bar')
-      @cache.clear
-      assert_nil @cache.read('foo')
-    end
-
-    assert_nil @cache.read('foo')
-  end
-
-  def test_local_cache_of_write
-    @cache.with_local_cache do
-      @cache.write('foo', 'bar')
-      @peek.delete('foo')
-      assert_equal 'bar', @cache.read('foo')
-    end
-  end
-
-  def test_local_cache_of_read
-    @cache.write('foo', 'bar')
-    @cache.with_local_cache do
-      assert_equal 'bar', @cache.read('foo')
-    end
-  end
-
-  def test_local_cache_of_read_nil
-    @cache.with_local_cache do
-      assert_equal nil, @cache.read('foo')
-      @cache.send(:bypass_local_cache) { @cache.write 'foo', 'bar' }
-      assert_equal nil, @cache.read('foo')
-    end
-  end
-
-  def test_local_cache_fetch
-    @cache.with_local_cache do
-      @cache.send(:local_cache).write 'foo', 'bar'
-      assert_equal 'bar', @cache.send(:local_cache).fetch('foo')
-    end
-  end
-
-  def test_local_cache_of_write_nil
-    @cache.with_local_cache do
-      assert @cache.write('foo', nil)
-      assert_nil @cache.read('foo')
-      @peek.write('foo', 'bar')
-      assert_nil @cache.read('foo')
-    end
-  end
-
-  def test_local_cache_of_delete
-    @cache.with_local_cache do
-      @cache.write('foo', 'bar')
-      @cache.delete('foo')
-      assert_nil @cache.read('foo')
-    end
-  end
-
-  def test_local_cache_of_exist
-    @cache.with_local_cache do
-      @cache.write('foo', 'bar')
-      @peek.delete('foo')
-      assert @cache.exist?('foo')
-    end
-  end
-
-  def test_local_cache_of_increment
-    @cache.with_local_cache do
-      @cache.write('foo', 1, :raw => true)
-      @peek.write('foo', 2, :raw => true)
-      @cache.increment('foo')
-      assert_equal 3, @cache.read('foo')
-    end
-  end
-
-  def test_local_cache_of_decrement
-    @cache.with_local_cache do
-      @cache.write('foo', 1, :raw => true)
-      @peek.write('foo', 3, :raw => true)
-      @cache.decrement('foo')
-      assert_equal 2, @cache.read('foo')
-    end
-  end
-
-  def test_middleware
-    app = lambda { |env|
-      result = @cache.write('foo', 'bar')
-      assert_equal 'bar', @cache.read('foo') # make sure 'foo' was written
-      assert result
-      [200, {}, []]
-    }
-    app = @cache.middleware.new(app)
-    app.call({})
-  end
-
-  def test_can_call_deprecated_set_cache_value
-    @cache.with_local_cache do
-      assert_deprecated "`set_cache_value` is deprecated" do
-        @cache.send(:set_cache_value, 1, 'foo', :ignored, {})
-      end
-      assert_equal 1, @cache.read('foo')
-    end
-  end
-end
-
-module AutoloadingCacheBehavior
-  include DependenciesTestHelpers
-  def test_simple_autoloading
-    with_autoloading_fixtures do
-      @cache.write('foo', EM.new)
-    end
-
-    remove_constants(:EM)
-    ActiveSupport::Dependencies.clear
-
-    with_autoloading_fixtures do
-      assert_kind_of EM, @cache.read('foo')
-    end
-
-    remove_constants(:EM)
-    ActiveSupport::Dependencies.clear
-  end
-
-  def test_two_classes_autoloading
-    with_autoloading_fixtures do
-      @cache.write('foo', [EM.new, ClassFolder.new])
-    end
-
-    remove_constants(:EM, :ClassFolder)
-    ActiveSupport::Dependencies.clear
-
-    with_autoloading_fixtures do
-      loaded = @cache.read('foo')
-      assert_kind_of Array, loaded
-      assert_equal 2, loaded.size
-      assert_kind_of EM, loaded[0]
-      assert_kind_of ClassFolder, loaded[1]
-    end
-
-    remove_constants(:EM, :ClassFolder)
-    ActiveSupport::Dependencies.clear
-  end
-end
-
-class FileStoreTest < ActiveSupport::TestCase
-  def setup
-    Dir.mkdir(cache_dir) unless File.exist?(cache_dir)
-    @cache = ActiveSupport::Cache.lookup_store(:file_store, cache_dir, :expires_in => 60)
-    @peek = ActiveSupport::Cache.lookup_store(:file_store, cache_dir, :expires_in => 60)
-    @cache_with_pathname = ActiveSupport::Cache.lookup_store(:file_store, Pathname.new(cache_dir), :expires_in => 60)
-
-    @buffer = StringIO.new
-    @cache.logger = ActiveSupport::Logger.new(@buffer)
-  end
-
-  def teardown
-    FileUtils.rm_r(cache_dir)
-  rescue Errno::ENOENT
-  end
-
-  def cache_dir
-    File.join(Dir.pwd, 'tmp_cache')
-  end
-
-  include CacheStoreBehavior
-  include LocalCacheBehavior
-  include CacheDeleteMatchedBehavior
-  include CacheIncrementDecrementBehavior
-  include AutoloadingCacheBehavior
-
-  def test_clear
-    gitkeep = File.join(cache_dir, ".gitkeep")
-    keep = File.join(cache_dir, ".keep")
-    FileUtils.touch([gitkeep, keep])
-    @cache.clear
-    assert File.exist?(gitkeep)
-    assert File.exist?(keep)
-  end
-
-  def test_clear_without_cache_dir
-    FileUtils.rm_r(cache_dir)
-    @cache.clear
-  end
-
-  def test_long_keys
-    @cache.write("a"*10000, 1)
-    assert_equal 1, @cache.read("a"*10000)
-  end
-
-  def test_long_uri_encoded_keys
-    @cache.write("%"*870, 1)
-    assert_equal 1, @cache.read("%"*870)
-  end
-
-  def test_key_transformation
-    key = @cache.send(:normalize_key, "views/index?id=1", {})
-    assert_equal "views/index?id=1", @cache.send(:file_path_key, key)
-  end
-
-  def test_key_transformation_with_pathname
-    FileUtils.touch(File.join(cache_dir, "foo"))
-    key = @cache_with_pathname.send(:normalize_key, "views/index?id=1", {})
-    assert_equal "views/index?id=1", @cache_with_pathname.send(:file_path_key, key)
-  end
-
-  # Test that generated cache keys are short enough to have Tempfile stuff added to them and
-  # remain valid
-  def test_filename_max_size
-    key = "#{'A' * ActiveSupport::Cache::FileStore::FILENAME_MAX_SIZE}"
-    path = @cache.send(:normalize_key, key, {})
-    Dir::Tmpname.create(path) do |tmpname, n, opts|
-      assert File.basename(tmpname+'.lock').length <= 255, "Temp filename too long: #{File.basename(tmpname+'.lock').length}"
-    end
-  end
-
-  # Because file systems have a maximum filename size, filenames > max size should be split in to directories
-  # If filename is 'AAAAB', where max size is 4, the returned path should be AAAA/B
-  def test_key_transformation_max_filename_size
-    key = "#{'A' * ActiveSupport::Cache::FileStore::FILENAME_MAX_SIZE}B"
-    path = @cache.send(:normalize_key, key, {})
-    assert path.split('/').all? { |dir_name| dir_name.size <= ActiveSupport::Cache::FileStore::FILENAME_MAX_SIZE}
-    assert_equal 'B', File.basename(path)
-  end
-
-  # If nothing has been stored in the cache, there is a chance the cache directory does not yet exist
-  # Ensure delete_matched gracefully handles this case
-  def test_delete_matched_when_cache_directory_does_not_exist
-    assert_nothing_raised do
-      ActiveSupport::Cache::FileStore.new('/test/cache/directory').delete_matched(/does_not_exist/)
-    end
-  end
-
-  def test_delete_does_not_delete_empty_parent_dir
-    sub_cache_dir = File.join(cache_dir, 'subdir/')
-    sub_cache_store = ActiveSupport::Cache::FileStore.new(sub_cache_dir)
-    assert_nothing_raised do
-      assert sub_cache_store.write('foo', 'bar')
-      assert sub_cache_store.delete('foo')
-    end
-    assert File.exist?(cache_dir), "Parent of top level cache dir was deleted!"
-    assert File.exist?(sub_cache_dir), "Top level cache dir was deleted!"
-    assert Dir.entries(sub_cache_dir).reject {|f| ActiveSupport::Cache::FileStore::EXCLUDED_DIRS.include?(f)}.empty?
-  end
-
-  def test_log_exception_when_cache_read_fails
-    File.stub(:exist?, -> { raise StandardError.new("failed") }) do
-      @cache.send(:read_entry, "winston", {})
-      assert @buffer.string.present?
-    end
-  end
-
-  def test_cleanup_removes_all_expired_entries
-    time = Time.now
-    @cache.write('foo', 'bar', expires_in: 10)
-    @cache.write('baz', 'qux')
-    @cache.write('quux', 'corge', expires_in: 20)
-    Time.stub(:now, time + 15) do
-      @cache.cleanup
-      assert_not @cache.exist?('foo')
-      assert @cache.exist?('baz')
-      assert @cache.exist?('quux')
-    end
-  end
-
-  def test_write_with_unless_exist
-    assert_equal true, @cache.write(1, "aaaaaaaaaa")
-    assert_equal false, @cache.write(1, "aaaaaaaaaa", unless_exist: true)
-    @cache.write(1, nil)
-    assert_equal false, @cache.write(1, "aaaaaaaaaa", unless_exist: true)
-  end
-
-  def test_can_call_deprecated_key_file_path
-    assert_deprecated "`key_file_path` is deprecated" do
-      assert_equal 111, @cache.send(:key_file_path, 111)
-    end
-  end
-end
-
-class MemoryStoreTest < ActiveSupport::TestCase
-  def setup
-    @record_size = ActiveSupport::Cache.lookup_store(:memory_store).send(:cached_size, 1, ActiveSupport::Cache::Entry.new("aaaaaaaaaa"))
-    @cache = ActiveSupport::Cache.lookup_store(:memory_store, :expires_in => 60, :size => @record_size * 10 + 1)
-  end
-
-  include CacheStoreBehavior
-  include CacheDeleteMatchedBehavior
-  include CacheIncrementDecrementBehavior
-
-  def test_prune_size
-    @cache.write(1, "aaaaaaaaaa") && sleep(0.001)
-    @cache.write(2, "bbbbbbbbbb") && sleep(0.001)
-    @cache.write(3, "cccccccccc") && sleep(0.001)
-    @cache.write(4, "dddddddddd") && sleep(0.001)
-    @cache.write(5, "eeeeeeeeee") && sleep(0.001)
-    @cache.read(2) && sleep(0.001)
-    @cache.read(4)
-    @cache.prune(@record_size * 3)
-    assert @cache.exist?(5)
-    assert @cache.exist?(4)
-    assert !@cache.exist?(3), "no entry"
-    assert @cache.exist?(2)
-    assert !@cache.exist?(1), "no entry"
-  end
-
-  def test_prune_size_on_write
-    @cache.write(1, "aaaaaaaaaa") && sleep(0.001)
-    @cache.write(2, "bbbbbbbbbb") && sleep(0.001)
-    @cache.write(3, "cccccccccc") && sleep(0.001)
-    @cache.write(4, "dddddddddd") && sleep(0.001)
-    @cache.write(5, "eeeeeeeeee") && sleep(0.001)
-    @cache.write(6, "ffffffffff") && sleep(0.001)
-    @cache.write(7, "gggggggggg") && sleep(0.001)
-    @cache.write(8, "hhhhhhhhhh") && sleep(0.001)
-    @cache.write(9, "iiiiiiiiii") && sleep(0.001)
-    @cache.write(10, "kkkkkkkkkk") && sleep(0.001)
-    @cache.read(2) && sleep(0.001)
-    @cache.read(4) && sleep(0.001)
-    @cache.write(11, "llllllllll")
-    assert @cache.exist?(11)
-    assert @cache.exist?(10)
-    assert @cache.exist?(9)
-    assert @cache.exist?(8)
-    assert @cache.exist?(7)
-    assert !@cache.exist?(6), "no entry"
-    assert !@cache.exist?(5), "no entry"
-    assert @cache.exist?(4)
-    assert !@cache.exist?(3), "no entry"
-    assert @cache.exist?(2)
-    assert !@cache.exist?(1), "no entry"
-  end
-
-  def test_prune_size_on_write_based_on_key_length
-    @cache.write(1, "aaaaaaaaaa") && sleep(0.001)
-    @cache.write(2, "bbbbbbbbbb") && sleep(0.001)
-    @cache.write(3, "cccccccccc") && sleep(0.001)
-    @cache.write(4, "dddddddddd") && sleep(0.001)
-    @cache.write(5, "eeeeeeeeee") && sleep(0.001)
-    @cache.write(6, "ffffffffff") && sleep(0.001)
-    @cache.write(7, "gggggggggg") && sleep(0.001)
-    @cache.write(8, "hhhhhhhhhh") && sleep(0.001)
-    @cache.write(9, "iiiiiiiiii") && sleep(0.001)
-    long_key = '*' * 2 * @record_size
-    @cache.write(long_key, "llllllllll")
-    assert @cache.exist?(long_key)
-    assert @cache.exist?(9)
-    assert @cache.exist?(8)
-    assert @cache.exist?(7)
-    assert @cache.exist?(6)
-    assert !@cache.exist?(5), "no entry"
-    assert !@cache.exist?(4), "no entry"
-    assert !@cache.exist?(3), "no entry"
-    assert !@cache.exist?(2), "no entry"
-    assert !@cache.exist?(1), "no entry"
-  end
-
-  def test_pruning_is_capped_at_a_max_time
-    def @cache.delete_entry (*args)
-      sleep(0.01)
-      super
-    end
-    @cache.write(1, "aaaaaaaaaa") && sleep(0.001)
-    @cache.write(2, "bbbbbbbbbb") && sleep(0.001)
-    @cache.write(3, "cccccccccc") && sleep(0.001)
-    @cache.write(4, "dddddddddd") && sleep(0.001)
-    @cache.write(5, "eeeeeeeeee") && sleep(0.001)
-    @cache.prune(30, 0.001)
-    assert @cache.exist?(5)
-    assert @cache.exist?(4)
-    assert @cache.exist?(3)
-    assert @cache.exist?(2)
-    assert !@cache.exist?(1)
-  end
-
-  def test_write_with_unless_exist
-    assert_equal true, @cache.write(1, "aaaaaaaaaa")
-    assert_equal false, @cache.write(1, "aaaaaaaaaa", :unless_exist => true)
-    @cache.write(1, nil)
-    assert_equal false, @cache.write(1, "aaaaaaaaaa", :unless_exist => true)
-  end
-end
-
-class MemCacheStoreTest < ActiveSupport::TestCase
-  require 'dalli'
-
-  begin
-    ss = Dalli::Client.new('localhost:11211').stats
-    raise Dalli::DalliError unless ss['localhost:11211']
-
-    MEMCACHE_UP = true
-  rescue Dalli::DalliError
-    $stderr.puts "Skipping memcached tests. Start memcached and try again."
-    MEMCACHE_UP = false
-  end
-
-  def setup
-    skip "memcache server is not up" unless MEMCACHE_UP
-
-    @cache = ActiveSupport::Cache.lookup_store(:mem_cache_store, :expires_in => 60)
-    @peek = ActiveSupport::Cache.lookup_store(:mem_cache_store)
-    @data = @cache.instance_variable_get(:@data)
-    @cache.clear
-    @cache.silence!
-    @cache.logger = ActiveSupport::Logger.new("/dev/null")
-  end
-
-  include CacheStoreBehavior
-  include LocalCacheBehavior
-  include CacheIncrementDecrementBehavior
-  include EncodedKeyCacheBehavior
-  include AutoloadingCacheBehavior
-
-  def test_raw_values
-    cache = ActiveSupport::Cache.lookup_store(:mem_cache_store, :raw => true)
-    cache.clear
-    cache.write("foo", 2)
-    assert_equal "2", cache.read("foo")
-  end
-
-  def test_raw_values_with_marshal
-    cache = ActiveSupport::Cache.lookup_store(:mem_cache_store, :raw => true)
-    cache.clear
-    cache.write("foo", Marshal.dump([]))
-    assert_equal [], cache.read("foo")
-  end
-
-  def test_local_cache_raw_values
-    cache = ActiveSupport::Cache.lookup_store(:mem_cache_store, :raw => true)
-    cache.clear
-    cache.with_local_cache do
-      cache.write("foo", 2)
-      assert_equal "2", cache.read("foo")
-    end
-  end
-
-  def test_local_cache_raw_values_with_marshal
-    cache = ActiveSupport::Cache.lookup_store(:mem_cache_store, :raw => true)
-    cache.clear
-    cache.with_local_cache do
-      cache.write("foo", Marshal.dump([]))
-      assert_equal [], cache.read("foo")
-    end
-  end
-
-  def test_read_should_return_a_different_object_id_each_time_it_is_called
-    @cache.write('foo', 'bar')
-    value = @cache.read('foo')
-    assert_not_equal value.object_id, @cache.read('foo').object_id
-    value << 'bingo'
-    assert_not_equal value, @cache.read('foo')
-  end
-
-  def test_can_call_deprecated_escape_key
-    assert_deprecated "`escape_key` is deprecated" do
-      assert_equal 111, @cache.send(:escape_key, 111)
-    end
-  end
-end
-
-class NullStoreTest < ActiveSupport::TestCase
-  def setup
-    @cache = ActiveSupport::Cache.lookup_store(:null_store)
-  end
-
-  def test_clear
-    @cache.clear
-  end
-
-  def test_cleanup
-    @cache.cleanup
-  end
-
-  def test_write
-    assert_equal true, @cache.write("name", "value")
-  end
-
-  def test_read
-    @cache.write("name", "value")
-    assert_nil @cache.read("name")
-  end
-
-  def test_delete
-    @cache.write("name", "value")
-    assert_equal false, @cache.delete("name")
-  end
-
-  def test_increment
-    @cache.write("name", 1, :raw => true)
-    assert_nil @cache.increment("name")
-  end
-
-  def test_decrement
-    @cache.write("name", 1, :raw => true)
-    assert_nil @cache.increment("name")
-  end
-
-  def test_delete_matched
-    @cache.write("name", "value")
-    @cache.delete_matched(/name/)
-  end
-
-  def test_local_store_strategy
-    @cache.with_local_cache do
-      @cache.write("name", "value")
-      assert_equal "value", @cache.read("name")
-      @cache.delete("name")
-      assert_nil @cache.read("name")
-      @cache.write("name", "value")
-    end
-    assert_nil @cache.read("name")
-  end
-end
-
-class CacheStoreLoggerTest < ActiveSupport::TestCase
-  def setup
-    @cache = ActiveSupport::Cache.lookup_store(:memory_store)
-
-    @buffer = StringIO.new
-    @cache.logger = ActiveSupport::Logger.new(@buffer)
-  end
-
-  def test_logging
-    @cache.fetch('foo') { 'bar' }
-    assert @buffer.string.present?
-  end
-
-  def test_log_with_string_namespace
-    @cache.fetch('foo', {namespace: 'string_namespace'}) { 'bar' }
-    assert_match %r{string_namespace:foo}, @buffer.string
-  end
-
-  def test_log_with_proc_namespace
-    proc = Proc.new do
-      "proc_namespace"
-    end
-    @cache.fetch('foo', {:namespace => proc}) { 'bar' }
-    assert_match %r{proc_namespace:foo}, @buffer.string
-  end
-
-  def test_mute_logging
-    @cache.mute { @cache.fetch('foo') { 'bar' } }
-    assert @buffer.string.blank?
-  end
-end
-
-class CacheEntryTest < ActiveSupport::TestCase
-  def test_expired
-    entry = ActiveSupport::Cache::Entry.new("value")
-    assert !entry.expired?, 'entry not expired'
-    entry = ActiveSupport::Cache::Entry.new("value", :expires_in => 60)
-    assert !entry.expired?, 'entry not expired'
-    Time.stub(:now, Time.now + 61) do
-      assert entry.expired?, 'entry is expired'
-    end
-  end
-
-  def test_compress_values
-    value = "value" * 100
-    entry = ActiveSupport::Cache::Entry.new(value, :compress => true, :compress_threshold => 1)
-    assert_equal value, entry.value
-    assert(value.bytesize > entry.size, "value is compressed")
-  end
-
-  def test_non_compress_values
-    value = "value" * 100
-    entry = ActiveSupport::Cache::Entry.new(value)
-    assert_equal value, entry.value
-    assert_equal value.bytesize, entry.size
-  end
-end
diff --git a/activesupport/test/callback_inheritance_test.rb b/activesupport/test/callback_inheritance_test.rb
index 1adfe4edf4..67813a749e 100644
--- a/activesupport/test/callback_inheritance_test.rb
+++ b/activesupport/test/callback_inheritance_test.rb
@@ -1,4 +1,6 @@
-require 'abstract_unit'
+# frozen_string_literal: true
+
+require "abstract_unit"
 
 class GrandParent
   include ActiveSupport::Callbacks
@@ -9,8 +11,8 @@ class GrandParent
   end
 
   define_callbacks :dispatch
-  set_callback :dispatch, :before, :before1, :before2, :if => proc {|c| c.action_name == "index" || c.action_name == "update" }
-  set_callback :dispatch, :after, :after1, :after2, :if => proc {|c| c.action_name == "update" || c.action_name == "delete" }
+  set_callback :dispatch, :before, :before1, :before2, if: proc { |c| c.action_name == "index" || c.action_name == "update" }
+  set_callback :dispatch, :after, :after1, :after2, if: proc { |c| c.action_name == "update" || c.action_name == "delete" }
 
   def before1
     @log << "before1"
@@ -37,12 +39,12 @@ class GrandParent
 end
 
 class Parent < GrandParent
-  skip_callback :dispatch, :before, :before2, :unless => proc {|c| c.action_name == "update" }
-  skip_callback :dispatch, :after, :after2, :unless => proc {|c| c.action_name == "delete" }
+  skip_callback :dispatch, :before, :before2, unless: proc { |c| c.action_name == "update" }
+  skip_callback :dispatch, :after, :after2, unless: proc { |c| c.action_name == "delete" }
 end
 
 class Child < GrandParent
-  skip_callback :dispatch, :before, :before2, :unless => proc {|c| c.action_name == "update" }, :if => :state_open?
+  skip_callback :dispatch, :before, :before2, unless: proc { |c| c.action_name == "update" }, if: :state_open?
 
   def state_open?
     @state == :open
diff --git a/activesupport/test/callbacks_test.rb b/activesupport/test/callbacks_test.rb
index a624473f46..30f1632460 100644
--- a/activesupport/test/callbacks_test.rb
+++ b/activesupport/test/callbacks_test.rb
@@ -1,4 +1,6 @@
-require 'abstract_unit'
+# frozen_string_literal: true
+
+require "abstract_unit"
 
 module CallbacksTest
   class Record
@@ -23,10 +25,6 @@ module CallbacksTest
         method_name
       end
 
-      def callback_string(callback_method)
-        "history << [#{callback_method.to_sym.inspect}, :string]"
-      end
-
       def callback_proc(callback_method)
         Proc.new { |model| model.history << [callback_method, :proc] }
       end
@@ -56,27 +54,30 @@ module CallbacksTest
   end
 
   class Person < Record
+    attr_accessor :save_fails
+
     [:before_save, :after_save].each do |callback_method|
       callback_method_sym = callback_method.to_sym
       send(callback_method, callback_symbol(callback_method_sym))
-      ActiveSupport::Deprecation.silence { send(callback_method, callback_string(callback_method_sym)) }
       send(callback_method, callback_proc(callback_method_sym))
-      send(callback_method, callback_object(callback_method_sym.to_s.gsub(/_save/, '')))
+      send(callback_method, callback_object(callback_method_sym.to_s.gsub(/_save/, "")))
       send(callback_method, CallbackClass)
       send(callback_method) { |model| model.history << [callback_method_sym, :block] }
     end
 
     def save
-      run_callbacks :save
+      run_callbacks :save do
+        raise "inside save" if save_fails
+      end
     end
   end
 
   class PersonSkipper < Person
-    skip_callback :save, :before, :before_save_method, :if => :yes
-    skip_callback :save, :after,  :after_save_method, :unless => :yes
-    skip_callback :save, :after,  :after_save_method, :if => :no
-    skip_callback :save, :before, :before_save_method, :unless => :no
-    skip_callback :save, :before, CallbackClass , :if => :yes
+    skip_callback :save, :before, :before_save_method, if: :yes
+    skip_callback :save, :after,  :after_save_method, unless: :yes
+    skip_callback :save, :after,  :after_save_method, if: :no
+    skip_callback :save, :before, :before_save_method, unless: :no
+    skip_callback :save, :before, CallbackClass, if: :yes
     def yes; true; end
     def no; false; end
   end
@@ -89,7 +90,7 @@ module CallbacksTest
 
     define_callbacks :dispatch
 
-    set_callback :dispatch, :before, :log, :unless => proc {|c| c.action_name == :index || c.action_name == :show }
+    set_callback :dispatch, :before, :log, unless: proc { |c| c.action_name == :index || c.action_name == :show }
     set_callback :dispatch, :after, :log2
 
     attr_reader :action_name, :logger
@@ -114,7 +115,7 @@ module CallbacksTest
   end
 
   class Child < ParentController
-    skip_callback :dispatch, :before, :log, :if => proc {|c| c.action_name == :update}
+    skip_callback :dispatch, :before, :log, if: proc { |c| c.action_name == :update }
     skip_callback :dispatch, :after, :log2
   end
 
@@ -125,10 +126,10 @@ module CallbacksTest
       super
     end
 
-    before_save Proc.new {|r| r.history << [:before_save, :starts_true, :if] }, :if => :starts_true
-    before_save Proc.new {|r| r.history << [:before_save, :starts_false, :if] }, :if => :starts_false
-    before_save Proc.new {|r| r.history << [:before_save, :starts_true, :unless] }, :unless => :starts_true
-    before_save Proc.new {|r| r.history << [:before_save, :starts_false, :unless] }, :unless => :starts_false
+    before_save Proc.new { |r| r.history << [:before_save, :starts_true, :if] }, if: :starts_true
+    before_save Proc.new { |r| r.history << [:before_save, :starts_false, :if] }, if: :starts_false
+    before_save Proc.new { |r| r.history << [:before_save, :starts_true, :unless] }, unless: :starts_true
+    before_save Proc.new { |r| r.history << [:before_save, :starts_false, :unless] }, unless: :starts_false
 
     def starts_true
       if @@starts_true
@@ -181,27 +182,20 @@ module CallbacksTest
     end
   end
 
-
-
   class ConditionalPerson < Record
     # proc
-    before_save Proc.new { |r| r.history << [:before_save, :proc] }, :if => Proc.new { |r| true }
-    before_save Proc.new { |r| r.history << "b00m" }, :if => Proc.new { |r| false }
-    before_save Proc.new { |r| r.history << [:before_save, :proc] }, :unless => Proc.new { |r| false }
-    before_save Proc.new { |r| r.history << "b00m" }, :unless => Proc.new { |r| true }
+    before_save Proc.new { |r| r.history << [:before_save, :proc] }, if: Proc.new { |r| true }
+    before_save Proc.new { |r| r.history << "b00m" }, if: Proc.new { |r| false }
+    before_save Proc.new { |r| r.history << [:before_save, :proc] }, unless: Proc.new { |r| false }
+    before_save Proc.new { |r| r.history << "b00m" }, unless: Proc.new { |r| true }
     # symbol
-    before_save Proc.new { |r| r.history << [:before_save, :symbol] }, :if => :yes
-    before_save Proc.new { |r| r.history << "b00m" }, :if => :no
-    before_save Proc.new { |r| r.history << [:before_save, :symbol] }, :unless => :no
-    before_save Proc.new { |r| r.history << "b00m" }, :unless => :yes
-    # string
-    before_save Proc.new { |r| r.history << [:before_save, :string] }, :if => 'yes'
-    before_save Proc.new { |r| r.history << "b00m" }, :if => 'no'
-    before_save Proc.new { |r| r.history << [:before_save, :string] }, :unless => 'no'
-    before_save Proc.new { |r| r.history << "b00m" }, :unless => 'yes'
+    before_save Proc.new { |r| r.history << [:before_save, :symbol] }, if: :yes
+    before_save Proc.new { |r| r.history << "b00m" }, if: :no
+    before_save Proc.new { |r| r.history << [:before_save, :symbol] }, unless: :no
+    before_save Proc.new { |r| r.history << "b00m" }, unless: :yes
     # Combined if and unless
-    before_save Proc.new { |r| r.history << [:before_save, :combined_symbol] }, :if => :yes, :unless => :no
-    before_save Proc.new { |r| r.history << "b00m" }, :if => :yes, :unless => :yes
+    before_save Proc.new { |r| r.history << [:before_save, :combined_symbol] }, if: :yes, unless: :no
+    before_save Proc.new { |r| r.history << "b00m" }, if: :yes, unless: :yes
 
     def yes; true; end
     def other_yes; true; end
@@ -222,26 +216,64 @@ module CallbacksTest
     define_callbacks :save
   end
 
-  class AroundPerson < MySuper
+  class MySlate < MySuper
     attr_reader :history
+    attr_accessor :save_fails
 
-    set_callback :save, :before, :nope,           :if =>     :no
-    set_callback :save, :before, :nope,           :unless => :yes
-    set_callback :save, :after,  :tweedle
-    ActiveSupport::Deprecation.silence { set_callback :save, :before, "tweedle_dee" }
-    set_callback :save, :before, proc {|m| m.history << "yup" }
-    set_callback :save, :before, :nope,           :if =>     proc { false }
-    set_callback :save, :before, :nope,           :unless => proc { true }
-    set_callback :save, :before, :yup,            :if =>     proc { true }
-    set_callback :save, :before, :yup,            :unless => proc { false }
-    set_callback :save, :around, :tweedle_dum
-    set_callback :save, :around, :w0tyes,         :if =>     :yes
-    set_callback :save, :around, :w0tno,          :if =>     :no
-    set_callback :save, :around, :tweedle_deedle
+    def initialize
+      @history = []
+    end
+
+    def save
+      run_callbacks :save do
+        raise "inside save" if save_fails
+        @history << "running"
+      end
+    end
 
     def no; false; end
     def yes; true; end
 
+    def method_missing(sym, *)
+      case sym
+      when /^log_(.*)/
+        @history << $1
+        nil
+      when /^wrap_(.*)/
+        @history << "wrap_#$1"
+        yield
+        @history << "unwrap_#$1"
+        nil
+      when /^double_(.*)/
+        @history << "first_#$1"
+        yield
+        @history << "second_#$1"
+        yield
+        @history << "third_#$1"
+      else
+        super
+      end
+    end
+
+    def respond_to_missing?(sym)
+      sym =~ /^(log|wrap)_/ || super
+    end
+  end
+
+  class AroundPerson < MySlate
+    set_callback :save, :before, :nope,           if: :no
+    set_callback :save, :before, :nope,           unless: :yes
+    set_callback :save, :after,  :tweedle
+    set_callback :save, :before, proc { |m| m.history << "yup" }
+    set_callback :save, :before, :nope,           if: proc { false }
+    set_callback :save, :before, :nope,           unless: proc { true }
+    set_callback :save, :before, :yup,            if: proc { true }
+    set_callback :save, :before, :yup,            unless: proc { false }
+    set_callback :save, :around, :tweedle_dum
+    set_callback :save, :around, :w0tyes,         if: :yes
+    set_callback :save, :around, :w0tno,          if: :no
+    set_callback :save, :around, :tweedle_deedle
+
     def nope
       @history << "boom"
     end
@@ -261,10 +293,6 @@ module CallbacksTest
       yield
     end
 
-    def tweedle_dee
-      @history << "tweedle dee"
-    end
-
     def tweedle_dum
       @history << "tweedle dum pre"
       yield
@@ -280,16 +308,6 @@ module CallbacksTest
       yield
       @history << "tweedle deedle post"
     end
-
-    def initialize
-      @history = []
-    end
-
-    def save
-      run_callbacks :save do
-        @history << "running"
-      end
-    end
   end
 
   class AroundPersonResult < MySuper
@@ -323,7 +341,7 @@ module CallbacksTest
     define_callbacks :save
     attr_reader :stuff
 
-    set_callback :save, :before, :action, :if => :yes
+    set_callback :save, :before, :action, if: :yes
 
     def yes() true end
 
@@ -361,7 +379,6 @@ module CallbacksTest
   end
 
   class ExtendCallbacks
-
     include ActiveSupport::Callbacks
 
     define_callbacks :save
@@ -391,7 +408,6 @@ module CallbacksTest
       around = AroundPerson.new
       around.save
       assert_equal [
-        "tweedle dee",
         "yup", "yup",
         "tweedle dum pre",
         "w0tyes before",
@@ -405,6 +421,97 @@ module CallbacksTest
     end
   end
 
+  class DoubleYieldTest < ActiveSupport::TestCase
+    class DoubleYieldModel < MySlate
+      set_callback :save, :around, :wrap_outer
+      set_callback :save, :around, :double_trouble
+      set_callback :save, :around, :wrap_inner
+    end
+
+    def test_double_save
+      double = DoubleYieldModel.new
+      double.save
+      assert_equal [
+        "wrap_outer",
+        "first_trouble",
+        "wrap_inner",
+        "running",
+        "unwrap_inner",
+        "second_trouble",
+        "wrap_inner",
+        "running",
+        "unwrap_inner",
+        "third_trouble",
+        "unwrap_outer",
+      ], double.history
+    end
+  end
+
+  class CallStackTest < ActiveSupport::TestCase
+    def test_tidy_call_stack
+      around = AroundPerson.new
+      around.save_fails = true
+
+      exception = (around.save rescue $!)
+
+      # Make sure we have the exception we're expecting
+      assert_equal "inside save", exception.message
+
+      call_stack = exception.backtrace_locations
+      call_stack.pop caller_locations(0).size
+
+      # Yes, this looks like an implementation test, but it's the least
+      # obtuse way of asserting that there aren't a load of entries in
+      # the call stack for each callback.
+      #
+      # If you've renamed a method, or squeezed more lines out, go ahead
+      # and update this assertion. But if you're here because a
+      # refactoring added new lines, please reconsider.
+
+      # As shown here, our current budget is one line for run_callbacks
+      # itself, plus N+1 lines where N is the number of :around
+      # callbacks that have been invoked, if there are any (plus
+      # whatever the callbacks do themselves, of course).
+
+      assert_equal [
+        "block in save",
+        "block in run_callbacks",
+        "tweedle_deedle",
+        "block in run_callbacks",
+        "w0tyes",
+        "block in run_callbacks",
+        "tweedle_dum",
+        "block in run_callbacks",
+        ("call" if RUBY_VERSION < "2.3"),
+        "run_callbacks",
+        "save"
+      ].compact, call_stack.map(&:label)
+    end
+
+    def test_short_call_stack
+      person = Person.new
+      person.save_fails = true
+
+      exception = (person.save rescue $!)
+
+      # Make sure we have the exception we're expecting
+      assert_equal "inside save", exception.message
+
+      call_stack = exception.backtrace_locations
+      call_stack.pop caller_locations(0).size
+
+      # This budget much simpler: with no :around callbacks invoked,
+      # there should be just one line. run_callbacks yields directly
+      # back to its caller.
+
+      assert_equal [
+        "block in save",
+        "run_callbacks",
+        "save"
+      ], call_stack.map(&:label)
+    end
+  end
+
   class AroundCallbackResultTest < ActiveSupport::TestCase
     def test_save_around
       around = AroundPersonResult.new
@@ -419,7 +526,6 @@ module CallbacksTest
       assert_equal [], person.history
       person.save
       assert_equal [
-        [:before_save, :string],
         [:before_save, :proc],
         [:before_save, :object],
         [:before_save, :block],
@@ -427,7 +533,6 @@ module CallbacksTest
         [:after_save, :class],
         [:after_save, :object],
         [:after_save, :proc],
-        [:after_save, :string],
         [:after_save, :symbol]
       ], person.history
     end
@@ -446,21 +551,18 @@ module CallbacksTest
         [:after_save, :class],
         [:after_save, :object],
         [:after_save, :proc],
-        [:after_save, :string],
         [:after_save, :symbol]
       ], person.history
     end
   end
 
   class CallbacksTest < ActiveSupport::TestCase
-
     def test_save_person
       person = Person.new
       assert_equal [], person.history
       person.save
       assert_equal [
         [:before_save, :symbol],
-        [:before_save, :string],
         [:before_save, :proc],
         [:before_save, :object],
         [:before_save, :class],
@@ -469,7 +571,6 @@ module CallbacksTest
         [:after_save, :class],
         [:after_save, :object],
         [:after_save, :proc],
-        [:after_save, :string],
         [:after_save, :symbol]
       ], person.history
     end
@@ -484,15 +585,11 @@ module CallbacksTest
         [:before_save, :proc],
         [:before_save, :symbol],
         [:before_save, :symbol],
-        [:before_save, :string],
-        [:before_save, :string],
         [:before_save, :combined_symbol],
       ], person.history
     end
   end
 
-
-
   class ResetCallbackTest < ActiveSupport::TestCase
     def test_save_conditional_person
       person = CleanPerson.new
@@ -637,7 +734,7 @@ module CallbacksTest
   class CustomScopeObject
     include ActiveSupport::Callbacks
 
-    define_callbacks :save, :scope => [:kind, :name]
+    define_callbacks :save, scope: [:kind, :name]
     set_callback :save, :before, CallbackObject.new
 
     attr_accessor :record
@@ -765,37 +862,11 @@ module CallbacksTest
     end
   end
 
-  class CallbackFalseTerminatorWithoutConfigTest < ActiveSupport::TestCase
-    def test_returning_false_does_not_halt_callback_if_config_variable_is_not_set
+  class CallbackFalseTerminatorTest < ActiveSupport::TestCase
+    def test_returning_false_does_not_halt_callback
       obj = CallbackFalseTerminator.new
       obj.save
-      assert_equal nil, obj.halted
-      assert obj.saved
-    end
-  end
-
-  class CallbackFalseTerminatorWithConfigTrueTest < ActiveSupport::TestCase
-    def setup
-      ActiveSupport::Callbacks.halt_and_display_warning_on_return_false = true
-    end
-
-    def test_returning_false_does_not_halt_callback_if_config_variable_is_true
-      obj = CallbackFalseTerminator.new
-      obj.save
-      assert_equal nil, obj.halted
-      assert obj.saved
-    end
-  end
-
-  class CallbackFalseTerminatorWithConfigFalseTest < ActiveSupport::TestCase
-    def setup
-      ActiveSupport::Callbacks.halt_and_display_warning_on_return_false = false
-    end
-
-    def test_returning_false_does_not_halt_callback_if_config_variable_is_false
-      obj = CallbackFalseTerminator.new
-      obj.save
-      assert_equal nil, obj.halted
+      assert_nil obj.halted
       assert obj.saved
     end
   end
@@ -810,7 +881,7 @@ module CallbacksTest
 
   class WriterSkipper < Person
     attr_accessor :age
-    skip_callback :save, :before, :before_save_method, :if => lambda {self.age > 21}
+    skip_callback :save, :before, :before_save_method, if: -> { age > 21 }
   end
 
   class WriterCallbacksTest < ActiveSupport::TestCase
@@ -821,7 +892,6 @@ module CallbacksTest
       writer.save
       assert_equal [
         [:before_save, :symbol],
-        [:before_save, :string],
         [:before_save, :proc],
         [:before_save, :object],
         [:before_save, :class],
@@ -830,7 +900,6 @@ module CallbacksTest
         [:after_save, :class],
         [:after_save, :object],
         [:after_save, :proc],
-        [:after_save, :string],
         [:after_save, :symbol]
       ], writer.history
     end
@@ -885,7 +954,7 @@ module CallbacksTest
 
     def test_proc_arity_2
       assert_raises(ArgumentError) do
-        klass = build_class(->(x,y) { })
+        klass = build_class(->(x, y) {})
         klass.new.run
       end
     end
@@ -903,7 +972,7 @@ module CallbacksTest
       Class.new {
         include ActiveSupport::Callbacks
         define_callbacks :foo
-        set_callback :foo, :before, :foo, :if => callback
+        set_callback :foo, :before, :foo, if: callback
         def foo; end
         def run; run_callbacks :foo; end
       }
@@ -918,11 +987,11 @@ module CallbacksTest
       }
       klass = Class.new {
         include ActiveSupport::Callbacks
-        define_callbacks :foo, :scope => [:name]
-        set_callback :foo, :before, :foo, :if => callback
+        define_callbacks :foo, scope: [:name]
+        set_callback :foo, :before, :foo, if: callback
         def run; run_callbacks :foo; end
         private
-        def foo; end
+          def foo; end
       }
       object = klass.new
       object.run
@@ -964,7 +1033,7 @@ module CallbacksTest
 
     def test_proc_arity2
       assert_raises(ArgumentError) do
-        object = build_class(->(a,b) { }).new
+        object = build_class(->(a, b) {}).new
         object.run
       end
     end
@@ -1044,14 +1113,6 @@ module CallbacksTest
       assert_equal 1, calls.length
     end
 
-    def test_add_eval
-      calls = []
-      klass = ActiveSupport::Deprecation.silence { build_class("bar") }
-      klass.class_eval { define_method(:bar) { calls << klass } }
-      klass.new.run
-      assert_equal 1, calls.length
-    end
-
     def test_skip_class # removes one at a time
       calls = []
       callback = Class.new {
@@ -1086,7 +1147,7 @@ module CallbacksTest
 
     def test_skip_string # raises error
       calls = []
-      klass =  ActiveSupport::Deprecation.silence { build_class("bar") }
+      klass = build_class(:bar)
       klass.class_eval { define_method(:bar) { calls << klass } }
       assert_raises(ArgumentError) { klass.skip "bar" }
       klass.new.run
@@ -1112,12 +1173,24 @@ module CallbacksTest
     end
   end
 
-  class DeprecatedWarningTest < ActiveSupport::TestCase
-    def test_deprecate_string_callback
+  class NotSupportedStringConditionalTest < ActiveSupport::TestCase
+    def test_string_conditional_options
       klass = Class.new(Record)
 
-      assert_deprecated do
-        klass.send :before_save, "tweedle_dee"
+      assert_raises(ArgumentError) { klass.before_save :tweedle, if: ["true"] }
+      assert_raises(ArgumentError) { klass.before_save :tweedle, if: "true" }
+      assert_raises(ArgumentError) { klass.after_save :tweedle, unless: "false" }
+      assert_raises(ArgumentError) { klass.skip_callback :save, :before, :tweedle, if: "true" }
+      assert_raises(ArgumentError) { klass.skip_callback :save, :after, :tweedle, unless: "false" }
+    end
+  end
+
+  class NotPermittedStringCallbackTest < ActiveSupport::TestCase
+    def test_passing_string_callback_is_not_permitted
+      klass = Class.new(Record)
+
+      assert_raises(ArgumentError) do
+        klass.before_save "tweedle"
       end
     end
   end
diff --git a/activesupport/test/class_cache_test.rb b/activesupport/test/class_cache_test.rb
index b96f476ce6..7b97028e8c 100644
--- a/activesupport/test/class_cache_test.rb
+++ b/activesupport/test/class_cache_test.rb
@@ -1,5 +1,7 @@
-require 'abstract_unit'
-require 'active_support/dependencies'
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "active_support/dependencies"
 
 module ActiveSupport
   module Dependencies
@@ -61,7 +63,7 @@ module ActiveSupport
 
       def test_safe_get_constantizes_doesnt_fail_on_invalid_names
         assert @cache.empty?
-        assert_equal nil, @cache.safe_get("OmgTotallyInvalidConstantName")
+        assert_nil @cache.safe_get("OmgTotallyInvalidConstantName")
       end
 
       def test_new_rejects_strings
diff --git a/activesupport/test/clean_backtrace_test.rb b/activesupport/test/clean_backtrace_test.rb
index 05580352a9..1b44c7c9bf 100644
--- a/activesupport/test/clean_backtrace_test.rb
+++ b/activesupport/test/clean_backtrace_test.rb
@@ -1,15 +1,17 @@
-require 'abstract_unit'
+# frozen_string_literal: true
+
+require "abstract_unit"
 
 class BacktraceCleanerFilterTest < ActiveSupport::TestCase
   def setup
     @bc = ActiveSupport::BacktraceCleaner.new
-    @bc.add_filter { |line| line.gsub("/my/prefix", '') }
+    @bc.add_filter { |line| line.gsub("/my/prefix", "") }
   end
 
   test "backtrace should filter all lines in a backtrace, removing prefixes" do
     assert_equal \
-        ["/my/class.rb", "/my/module.rb"],
-        @bc.clean(["/my/prefix/my/class.rb", "/my/prefix/my/module.rb"])
+      ["/my/class.rb", "/my/module.rb"],
+      @bc.clean(["/my/prefix/my/class.rb", "/my/prefix/my/module.rb"])
   end
 
   test "backtrace cleaner should allow removing filters" do
@@ -20,13 +22,12 @@ class BacktraceCleanerFilterTest < ActiveSupport::TestCase
   test "backtrace should contain unaltered lines if they dont match a filter" do
     assert_equal "/my/other_prefix/my/class.rb", @bc.clean([ "/my/other_prefix/my/class.rb" ]).first
   end
-
 end
 
 class BacktraceCleanerSilencerTest < ActiveSupport::TestCase
   def setup
     @bc = ActiveSupport::BacktraceCleaner.new
-    @bc.add_silencer { |line| line =~ /mongrel/ }
+    @bc.add_silencer { |line| line.include?("mongrel") }
   end
 
   test "backtrace should not contain lines that match the silencer" do
@@ -44,8 +45,8 @@ end
 class BacktraceCleanerMultipleSilencersTest < ActiveSupport::TestCase
   def setup
     @bc = ActiveSupport::BacktraceCleaner.new
-    @bc.add_silencer { |line| line =~ /mongrel/ }
-    @bc.add_silencer { |line| line =~ /yolo/ }
+    @bc.add_silencer { |line| line.include?("mongrel") }
+    @bc.add_silencer { |line| line.include?("yolo") }
   end
 
   test "backtrace should not contain lines that match the silencers" do
@@ -66,7 +67,7 @@ class BacktraceCleanerFilterAndSilencerTest < ActiveSupport::TestCase
   def setup
     @bc = ActiveSupport::BacktraceCleaner.new
     @bc.add_filter   { |line| line.gsub("/mongrel", "") }
-    @bc.add_silencer { |line| line =~ /mongrel/ }
+    @bc.add_silencer { |line| line.include?("mongrel") }
   end
 
   test "backtrace should not silence lines that has first had their silence hook filtered out" do
diff --git a/activesupport/test/clean_logger_test.rb b/activesupport/test/clean_logger_test.rb
index 02693a97dc..6d8f7064ce 100644
--- a/activesupport/test/clean_logger_test.rb
+++ b/activesupport/test/clean_logger_test.rb
@@ -1,6 +1,8 @@
-require 'abstract_unit'
-require 'stringio'
-require 'active_support/logger'
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "stringio"
+require "active_support/logger"
 
 class CleanLoggerTest < ActiveSupport::TestCase
   def setup
@@ -9,14 +11,14 @@ class CleanLoggerTest < ActiveSupport::TestCase
   end
 
   def test_format_message
-    @logger.error 'error'
+    @logger.error "error"
     assert_equal "error\n", @out.string
   end
 
   def test_datetime_format
     @logger.formatter = Logger::Formatter.new
     @logger.formatter.datetime_format = "%Y-%m-%d"
-    @logger.debug 'debug'
+    @logger.debug "debug"
     assert_equal "%Y-%m-%d", @logger.formatter.datetime_format
     assert_match(/D, \[\d\d\d\d-\d\d-\d\d#\d+\] DEBUG -- : debug/, @out.string)
   end
diff --git a/activesupport/test/concern_test.rb b/activesupport/test/concern_test.rb
index 8ea701cfb7..ef75a320d1 100644
--- a/activesupport/test/concern_test.rb
+++ b/activesupport/test/concern_test.rb
@@ -1,5 +1,7 @@
-require 'abstract_unit'
-require 'active_support/concern'
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "active_support/concern"
 
 class ConcernTest < ActiveSupport::TestCase
   module Baz
@@ -66,17 +68,17 @@ class ConcernTest < ActiveSupport::TestCase
   def test_module_is_included_normally
     @klass.include(Baz)
     assert_equal "baz", @klass.new.baz
-    assert @klass.included_modules.include?(ConcernTest::Baz)
+    assert_includes @klass.included_modules, ConcernTest::Baz
   end
 
   def test_class_methods_are_extended
     @klass.include(Baz)
     assert_equal "baz", @klass.baz
-    assert_equal ConcernTest::Baz::ClassMethods, (class << @klass; self.included_modules; end)[0]
+    assert_equal ConcernTest::Baz::ClassMethods, (class << @klass; included_modules; end)[0]
   end
 
   def test_class_methods_are_extended_only_on_expected_objects
-    ::Object.__send__(:include, Qux)
+    ::Object.include(Qux)
     Object.extend(Qux::ClassMethods)
     # module needs to be created after Qux is included in Object or bug won't
     # be triggered
@@ -105,7 +107,7 @@ class ConcernTest < ActiveSupport::TestCase
     assert_equal "bar", @klass.new.bar
     assert_equal "bar+baz", @klass.new.baz
     assert_equal "bar's baz + baz", @klass.baz
-    assert @klass.included_modules.include?(ConcernTest::Bar)
+    assert_includes @klass.included_modules, ConcernTest::Bar
   end
 
   def test_dependencies_with_multiple_modules
diff --git a/activesupport/test/concurrency/load_interlock_aware_monitor_test.rb b/activesupport/test/concurrency/load_interlock_aware_monitor_test.rb
new file mode 100644
index 0000000000..2d0f45ec5f
--- /dev/null
+++ b/activesupport/test/concurrency/load_interlock_aware_monitor_test.rb
@@ -0,0 +1,55 @@
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "concurrent/atomic/count_down_latch"
+require "active_support/concurrency/load_interlock_aware_monitor"
+
+module ActiveSupport
+  module Concurrency
+    class LoadInterlockAwareMonitorTest < ActiveSupport::TestCase
+      def setup
+        @monitor = ActiveSupport::Concurrency::LoadInterlockAwareMonitor.new
+      end
+
+      def test_entering_with_no_blocking
+        assert @monitor.mon_enter
+      end
+
+      def test_entering_with_blocking
+        load_interlock_latch = Concurrent::CountDownLatch.new
+        monitor_latch = Concurrent::CountDownLatch.new
+
+        able_to_use_monitor = false
+        able_to_load = false
+
+        thread_with_load_interlock = Thread.new do
+          ActiveSupport::Dependencies.interlock.running do
+            load_interlock_latch.count_down
+            monitor_latch.wait
+
+            @monitor.synchronize do
+              able_to_use_monitor = true
+            end
+          end
+        end
+
+        thread_with_monitor_lock = Thread.new do
+          @monitor.synchronize do
+            monitor_latch.count_down
+            load_interlock_latch.wait
+
+            ActiveSupport::Dependencies.interlock.loading do
+              able_to_load = true
+            end
+          end
+        end
+
+        thread_with_load_interlock.join
+        thread_with_monitor_lock.join
+
+        assert able_to_use_monitor
+        assert able_to_load
+      end
+    end
+  end
+end
diff --git a/activesupport/test/configurable_test.rb b/activesupport/test/configurable_test.rb
index 5d22ded2de..10719596df 100644
--- a/activesupport/test/configurable_test.rb
+++ b/activesupport/test/configurable_test.rb
@@ -1,5 +1,7 @@
-require 'abstract_unit'
-require 'active_support/configurable'
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "active_support/configurable"
 
 class ConfigurableActiveSupport < ActiveSupport::TestCase
   class Parent
@@ -111,7 +113,7 @@ class ConfigurableActiveSupport < ActiveSupport::TestCase
     end
   end
 
-  test 'the config_accessor method should not be publicly callable' do
+  test "the config_accessor method should not be publicly callable" do
     assert_raises NoMethodError do
       Class.new {
         include ActiveSupport::Configurable
@@ -121,11 +123,11 @@ class ConfigurableActiveSupport < ActiveSupport::TestCase
 
   def assert_method_defined(object, method)
     methods = object.public_methods.map(&:to_s)
-    assert methods.include?(method.to_s), "Expected #{methods.inspect} to include #{method.to_s.inspect}"
+    assert_includes methods, method.to_s, "Expected #{methods.inspect} to include #{method.to_s.inspect}"
   end
 
   def assert_method_not_defined(object, method)
     methods = object.public_methods.map(&:to_s)
-    assert !methods.include?(method.to_s), "Expected #{methods.inspect} to not include #{method.to_s.inspect}"
+    assert_not_includes methods, method.to_s, "Expected #{methods.inspect} to not include #{method.to_s.inspect}"
   end
 end
diff --git a/activesupport/test/constantize_test_cases.rb b/activesupport/test/constantize_test_cases.rb
index 1115bc0fd8..2c6145940b 100644
--- a/activesupport/test/constantize_test_cases.rb
+++ b/activesupport/test/constantize_test_cases.rb
@@ -1,4 +1,6 @@
-require 'dependencies_test_helpers'
+# frozen_string_literal: true
+
+require "dependencies_test_helpers"
 
 module Ace
   module Base
@@ -73,6 +75,11 @@ module ConstantizeTestCases
         yield("RaisesNoMethodError")
       end
     end
+
+    with_autoloading_fixtures do
+      yield("Prepend::SubClassConflict")
+      assert_equal "constant", defined?(Prepend::SubClassConflict)
+    end
   end
 
   def run_safe_constantize_tests_on
@@ -100,10 +107,10 @@ module ConstantizeTestCases
     assert_nil yield("Ace::Gas::ConstantizeTestCases")
     assert_nil yield("#<Class:0x7b8b718b>::Nested_1")
     assert_nil yield("Ace::gas")
-    assert_nil yield('Object::ABC')
-    assert_nil yield('Object::Object::Object::ABC')
-    assert_nil yield('A::Object::B')
-    assert_nil yield('A::Object::Object::Object::B')
+    assert_nil yield("Object::ABC")
+    assert_nil yield("Object::Object::Object::ABC")
+    assert_nil yield("A::Object::B")
+    assert_nil yield("A::Object::Object::Object::B")
 
     assert_raises(NameError) do
       with_autoloading_fixtures do
diff --git a/activesupport/test/core_ext/array/access_test.rb b/activesupport/test/core_ext/array/access_test.rb
index 1d834667f0..8c217023cf 100644
--- a/activesupport/test/core_ext/array/access_test.rb
+++ b/activesupport/test/core_ext/array/access_test.rb
@@ -1,5 +1,7 @@
-require 'abstract_unit'
-require 'active_support/core_ext/array'
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "active_support/core_ext/array"
 
 class AccessTest < ActiveSupport::TestCase
   def test_from
diff --git a/activesupport/test/core_ext/array/conversions_test.rb b/activesupport/test/core_ext/array/conversions_test.rb
index de36e2026d..0a7c43d421 100644
--- a/activesupport/test/core_ext/array/conversions_test.rb
+++ b/activesupport/test/core_ext/array/conversions_test.rb
@@ -1,37 +1,39 @@
-require 'abstract_unit'
-require 'active_support/core_ext/array'
-require 'active_support/core_ext/big_decimal'
-require 'active_support/core_ext/hash'
-require 'active_support/core_ext/string'
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "active_support/core_ext/array"
+require "active_support/core_ext/big_decimal"
+require "active_support/core_ext/hash"
+require "active_support/core_ext/string"
 
 class ToSentenceTest < ActiveSupport::TestCase
   def test_plain_array_to_sentence
     assert_equal "", [].to_sentence
-    assert_equal "one", ['one'].to_sentence
-    assert_equal "one and two", ['one', 'two'].to_sentence
-    assert_equal "one, two, and three", ['one', 'two', 'three'].to_sentence
+    assert_equal "one", ["one"].to_sentence
+    assert_equal "one and two", ["one", "two"].to_sentence
+    assert_equal "one, two, and three", ["one", "two", "three"].to_sentence
   end
 
   def test_to_sentence_with_words_connector
-    assert_equal "one two, and three", ['one', 'two', 'three'].to_sentence(words_connector: ' ')
-    assert_equal "one & two, and three", ['one', 'two', 'three'].to_sentence(words_connector: ' & ')
-    assert_equal "onetwo, and three", ['one', 'two', 'three'].to_sentence(words_connector: nil)
+    assert_equal "one two, and three", ["one", "two", "three"].to_sentence(words_connector: " ")
+    assert_equal "one & two, and three", ["one", "two", "three"].to_sentence(words_connector: " & ")
+    assert_equal "onetwo, and three", ["one", "two", "three"].to_sentence(words_connector: nil)
   end
 
   def test_to_sentence_with_last_word_connector
-    assert_equal "one, two, and also three", ['one', 'two', 'three'].to_sentence(last_word_connector: ', and also ')
-    assert_equal "one, twothree", ['one', 'two', 'three'].to_sentence(last_word_connector: nil)
-    assert_equal "one, two three", ['one', 'two', 'three'].to_sentence(last_word_connector: ' ')
-    assert_equal "one, two and three", ['one', 'two', 'three'].to_sentence(last_word_connector: ' and ')
+    assert_equal "one, two, and also three", ["one", "two", "three"].to_sentence(last_word_connector: ", and also ")
+    assert_equal "one, twothree", ["one", "two", "three"].to_sentence(last_word_connector: nil)
+    assert_equal "one, two three", ["one", "two", "three"].to_sentence(last_word_connector: " ")
+    assert_equal "one, two and three", ["one", "two", "three"].to_sentence(last_word_connector: " and ")
   end
 
   def test_two_elements
-    assert_equal "one and two", ['one', 'two'].to_sentence
-    assert_equal "one two", ['one', 'two'].to_sentence(two_words_connector: ' ')
+    assert_equal "one and two", ["one", "two"].to_sentence
+    assert_equal "one two", ["one", "two"].to_sentence(two_words_connector: " ")
   end
 
   def test_one_element
-    assert_equal "one", ['one'].to_sentence
+    assert_equal "one", ["one"].to_sentence
   end
 
   def test_one_element_not_same_object
@@ -40,31 +42,31 @@ class ToSentenceTest < ActiveSupport::TestCase
   end
 
   def test_one_non_string_element
-    assert_equal '1', [1].to_sentence
+    assert_equal "1", [1].to_sentence
   end
 
   def test_does_not_modify_given_hash
-    options = { words_connector: ' ' }
-    assert_equal "one two, and three", ['one', 'two', 'three'].to_sentence(options)
-    assert_equal({ words_connector: ' ' }, options)
+    options = { words_connector: " " }
+    assert_equal "one two, and three", ["one", "two", "three"].to_sentence(options)
+    assert_equal({ words_connector: " " }, options)
   end
 
   def test_with_blank_elements
-    assert_equal ", one, , two, and three", [nil, 'one', '', 'two', 'three'].to_sentence
+    assert_equal ", one, , two, and three", [nil, "one", "", "two", "three"].to_sentence
   end
 
   def test_with_invalid_options
     exception = assert_raise ArgumentError do
-      ['one', 'two'].to_sentence(passing: 'invalid option')
+      ["one", "two"].to_sentence(passing: "invalid option")
     end
 
-    assert_equal exception.message, "Unknown key: :passing. Valid keys are: :words_connector, :two_words_connector, :last_word_connector, :locale"
+    assert_equal "Unknown key: :passing. Valid keys are: :words_connector, :two_words_connector, :last_word_connector, :locale", exception.message
   end
 
   def test_always_returns_string
-    assert_instance_of String, [ActiveSupport::SafeBuffer.new('one')].to_sentence
-    assert_instance_of String, [ActiveSupport::SafeBuffer.new('one'), 'two'].to_sentence
-    assert_instance_of String, [ActiveSupport::SafeBuffer.new('one'), 'two', 'three'].to_sentence
+    assert_instance_of String, [ActiveSupport::SafeBuffer.new("one")].to_sentence
+    assert_instance_of String, [ActiveSupport::SafeBuffer.new("one"), "two"].to_sentence
+    assert_instance_of String, [ActiveSupport::SafeBuffer.new("one"), "two", "three"].to_sentence
   end
 end
 
@@ -88,32 +90,32 @@ class ToXmlTest < ActiveSupport::TestCase
   def test_to_xml_with_hash_elements
     xml = [
       { name: "David", age: 26, age_in_millis: 820497600000 },
-      { name: "Jason", age: 31, age_in_millis: BigDecimal.new('1.0') }
+      { name: "Jason", age: 31, age_in_millis: BigDecimal("1.0") }
     ].to_xml(skip_instruct: true, indent: 0)
 
     assert_equal '<objects type="array"><object>', xml.first(30)
-    assert xml.include?(%(<age type="integer">26</age>)), xml
-    assert xml.include?(%(<age-in-millis type="integer">820497600000</age-in-millis>)), xml
-    assert xml.include?(%(<name>David</name>)), xml
-    assert xml.include?(%(<age type="integer">31</age>)), xml
-    assert xml.include?(%(<age-in-millis type="decimal">1.0</age-in-millis>)), xml
-    assert xml.include?(%(<name>Jason</name>)), xml
+    assert_includes xml, %(<age type="integer">26</age>), xml
+    assert_includes xml, %(<age-in-millis type="integer">820497600000</age-in-millis>), xml
+    assert_includes xml, %(<name>David</name>), xml
+    assert_includes xml, %(<age type="integer">31</age>), xml
+    assert_includes xml, %(<age-in-millis type="decimal">1.0</age-in-millis>), xml
+    assert_includes xml, %(<name>Jason</name>), xml
   end
 
   def test_to_xml_with_non_hash_elements
     xml = %w[1 2 3].to_xml(skip_instruct: true, indent: 0)
 
     assert_equal '<strings type="array"><string', xml.first(29)
-    assert xml.include?(%(<string>2</string>)), xml
+    assert_includes xml, %(<string>2</string>), xml
   end
 
   def test_to_xml_with_non_hash_different_type_elements
-    xml = [1, 2.0, '3'].to_xml(skip_instruct: true, indent: 0)
+    xml = [1, 2.0, "3"].to_xml(skip_instruct: true, indent: 0)
 
     assert_equal '<objects type="array"><object', xml.first(29)
-    assert xml.include?(%(<object type="integer">1</object>)), xml
-    assert xml.include?(%(<object type="float">2.0</object>)), xml
-    assert xml.include?(%(object>3</object>)), xml
+    assert_includes xml, %(<object type="integer">1</object>), xml
+    assert_includes xml, %(<object type="float">2.0</object>), xml
+    assert_includes xml, %(object>3</object>), xml
   end
 
   def test_to_xml_with_dedicated_name
@@ -130,10 +132,10 @@ class ToXmlTest < ActiveSupport::TestCase
     ].to_xml(skip_instruct: true, skip_types: true, indent: 0)
 
     assert_equal "<objects><object>", xml.first(17)
-    assert xml.include?(%(<street-address>Paulina</street-address>))
-    assert xml.include?(%(<name>David</name>))
-    assert xml.include?(%(<street-address>Evergreen</street-address>))
-    assert xml.include?(%(<name>Jason</name>))
+    assert_includes xml, %(<street-address>Paulina</street-address>)
+    assert_includes xml, %(<name>David</name>)
+    assert_includes xml, %(<street-address>Evergreen</street-address>)
+    assert_includes xml, %(<name>Jason</name>)
   end
 
   def test_to_xml_with_indent_set
@@ -142,10 +144,10 @@ class ToXmlTest < ActiveSupport::TestCase
     ].to_xml(skip_instruct: true, skip_types: true, indent: 4)
 
     assert_equal "<objects>\n    <object>", xml.first(22)
-    assert xml.include?(%(\n        <street-address>Paulina</street-address>))
-    assert xml.include?(%(\n        <name>David</name>))
-    assert xml.include?(%(\n        <street-address>Evergreen</street-address>))
-    assert xml.include?(%(\n        <name>Jason</name>))
+    assert_includes xml, %(\n        <street-address>Paulina</street-address>)
+    assert_includes xml, %(\n        <name>David</name>)
+    assert_includes xml, %(\n        <street-address>Evergreen</street-address>)
+    assert_includes xml, %(\n        <name>Jason</name>)
   end
 
   def test_to_xml_with_dasherize_false
@@ -154,8 +156,8 @@ class ToXmlTest < ActiveSupport::TestCase
     ].to_xml(skip_instruct: true, skip_types: true, indent: 0, dasherize: false)
 
     assert_equal "<objects><object>", xml.first(17)
-    assert xml.include?(%(<street_address>Paulina</street_address>))
-    assert xml.include?(%(<street_address>Evergreen</street_address>))
+    assert_includes xml, %(<street_address>Paulina</street_address>)
+    assert_includes xml, %(<street_address>Evergreen</street_address>)
   end
 
   def test_to_xml_with_dasherize_true
@@ -164,14 +166,14 @@ class ToXmlTest < ActiveSupport::TestCase
     ].to_xml(skip_instruct: true, skip_types: true, indent: 0, dasherize: true)
 
     assert_equal "<objects><object>", xml.first(17)
-    assert xml.include?(%(<street-address>Paulina</street-address>))
-    assert xml.include?(%(<street-address>Evergreen</street-address>))
+    assert_includes xml, %(<street-address>Paulina</street-address>)
+    assert_includes xml, %(<street-address>Evergreen</street-address>)
   end
 
   def test_to_xml_with_instruct
     xml = [
       { name: "David", age: 26, age_in_millis: 820497600000 },
-      { name: "Jason", age: 31, age_in_millis: BigDecimal.new('1.0') }
+      { name: "Jason", age: 31, age_in_millis: BigDecimal("1.0") }
     ].to_xml(skip_instruct: false, indent: 0)
 
     assert_match(/^<\?xml [^>]*/, xml)
@@ -181,12 +183,12 @@ class ToXmlTest < ActiveSupport::TestCase
   def test_to_xml_with_block
     xml = [
       { name: "David", age: 26, age_in_millis: 820497600000 },
-      { name: "Jason", age: 31, age_in_millis: BigDecimal.new('1.0') }
+      { name: "Jason", age: 31, age_in_millis: BigDecimal("1.0") }
     ].to_xml(skip_instruct: true, indent: 0) do |builder|
       builder.count 2
     end
 
-    assert xml.include?(%(<count>2</count>)), xml
+    assert_includes xml, %(<count>2</count>), xml
   end
 
   def test_to_xml_with_empty
diff --git a/activesupport/test/core_ext/array/extract_options_test.rb b/activesupport/test/core_ext/array/extract_options_test.rb
index 0481a507cf..7a4b15cd71 100644
--- a/activesupport/test/core_ext/array/extract_options_test.rb
+++ b/activesupport/test/core_ext/array/extract_options_test.rb
@@ -1,6 +1,8 @@
-require 'abstract_unit'
-require 'active_support/core_ext/array'
-require 'active_support/core_ext/hash'
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "active_support/core_ext/array"
+require "active_support/core_ext/hash"
 
 class ExtractOptionsTest < ActiveSupport::TestCase
   class HashSubclass < Hash
diff --git a/activesupport/test/core_ext/array/grouping_test.rb b/activesupport/test/core_ext/array/grouping_test.rb
index 0682241f0b..c182b91826 100644
--- a/activesupport/test/core_ext/array/grouping_test.rb
+++ b/activesupport/test/core_ext/array/grouping_test.rb
@@ -1,39 +1,41 @@
-require 'abstract_unit'
-require 'active_support/core_ext/array'
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "active_support/core_ext/array"
 
 class GroupingTest < ActiveSupport::TestCase
   def setup
     # In Ruby < 2.4, test we avoid Integer#/ (redefined by mathn)
-    Fixnum.send :private, :/ unless Fixnum == Integer
+    Fixnum.send :private, :/ unless 0.class == Integer
   end
 
   def teardown
-    Fixnum.send :public, :/ unless Fixnum == Integer
+    Fixnum.send :public, :/ unless 0.class == Integer
   end
 
   def test_in_groups_of_with_perfect_fit
     groups = []
-    ('a'..'i').to_a.in_groups_of(3) do |group|
+    ("a".."i").to_a.in_groups_of(3) do |group|
       groups << group
     end
 
     assert_equal [%w(a b c), %w(d e f), %w(g h i)], groups
-    assert_equal [%w(a b c), %w(d e f), %w(g h i)], ('a'..'i').to_a.in_groups_of(3)
+    assert_equal [%w(a b c), %w(d e f), %w(g h i)], ("a".."i").to_a.in_groups_of(3)
   end
 
   def test_in_groups_of_with_padding
     groups = []
-    ('a'..'g').to_a.in_groups_of(3) do |group|
+    ("a".."g").to_a.in_groups_of(3) do |group|
       groups << group
     end
 
-    assert_equal [%w(a b c), %w(d e f), ['g', nil, nil]], groups
+    assert_equal [%w(a b c), %w(d e f), ["g", nil, nil]], groups
   end
 
   def test_in_groups_of_pads_with_specified_values
     groups = []
 
-    ('a'..'g').to_a.in_groups_of(3, 'foo') do |group|
+    ("a".."g").to_a.in_groups_of(3, "foo") do |group|
       groups << group
     end
 
@@ -43,7 +45,7 @@ class GroupingTest < ActiveSupport::TestCase
   def test_in_groups_of_without_padding
     groups = []
 
-    ('a'..'g').to_a.in_groups_of(3, false) do |group|
+    ("a".."g").to_a.in_groups_of(3, false) do |group|
       groups << group
     end
 
@@ -83,8 +85,8 @@ class GroupingTest < ActiveSupport::TestCase
 
     assert_equal [[1, 2, 3], [4, 5, nil], [6, 7, nil]],
       array.in_groups(3)
-    assert_equal [[1, 2, 3], [4, 5, 'foo'], [6, 7, 'foo']],
-      array.in_groups(3, 'foo')
+    assert_equal [[1, 2, 3], [4, 5, "foo"], [6, 7, "foo"]],
+      array.in_groups(3, "foo")
   end
 
   def test_in_groups_without_padding
@@ -114,7 +116,7 @@ class SplitTest < ActiveSupport::TestCase
   def test_split_with_block
     a = (1..10).to_a
     assert_equal [[1, 2], [4, 5], [7, 8], [10]], a.split { |i| i % 3 == 0 }
-    assert_equal [1, 2, 3, 4, 5, 6, 7, 8, 9 ,10], a
+    assert_equal [1, 2, 3, 4, 5, 6, 7, 8, 9, 10], a
   end
 
   def test_split_with_edge_values
diff --git a/activesupport/test/core_ext/array/prepend_append_test.rb b/activesupport/test/core_ext/array/prepend_append_test.rb
index 762aa69b2b..c34acd66ad 100644
--- a/activesupport/test/core_ext/array/prepend_append_test.rb
+++ b/activesupport/test/core_ext/array/prepend_append_test.rb
@@ -1,5 +1,7 @@
-require 'abstract_unit'
-require 'active_support/core_ext/array'
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "active_support/core_ext/array"
 
 class PrependAppendTest < ActiveSupport::TestCase
   def test_append
diff --git a/activesupport/test/core_ext/array/wrap_test.rb b/activesupport/test/core_ext/array/wrap_test.rb
index baf426506f..46564b4d73 100644
--- a/activesupport/test/core_ext/array/wrap_test.rb
+++ b/activesupport/test/core_ext/array/wrap_test.rb
@@ -1,5 +1,7 @@
-require 'abstract_unit'
-require 'active_support/core_ext/array'
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "active_support/core_ext/array"
 
 class WrapTest < ActiveSupport::TestCase
   class FakeCollection
diff --git a/activesupport/test/core_ext/bigdecimal_test.rb b/activesupport/test/core_ext/bigdecimal_test.rb
index 6e82e3892b..62588be33b 100644
--- a/activesupport/test/core_ext/bigdecimal_test.rb
+++ b/activesupport/test/core_ext/bigdecimal_test.rb
@@ -1,11 +1,13 @@
-require 'abstract_unit'
-require 'active_support/core_ext/big_decimal'
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "active_support/core_ext/big_decimal"
 
 class BigDecimalTest < ActiveSupport::TestCase
   def test_to_s
-    bd = BigDecimal.new '0.01'
-    assert_equal '0.01', bd.to_s
-    assert_equal '+0.01', bd.to_s('+F')
-    assert_equal '+0.0 1', bd.to_s('+1F')
+    bd = BigDecimal "0.01"
+    assert_equal "0.01", bd.to_s
+    assert_equal "+0.01", bd.to_s("+F")
+    assert_equal "+0.0 1", bd.to_s("+1F")
   end
 end
diff --git a/activesupport/test/core_ext/class/attribute_test.rb b/activesupport/test/core_ext/class/attribute_test.rb
index e7a1334db3..be6ad82367 100644
--- a/activesupport/test/core_ext/class/attribute_test.rb
+++ b/activesupport/test/core_ext/class/attribute_test.rb
@@ -1,23 +1,33 @@
-require 'abstract_unit'
-require 'active_support/core_ext/class/attribute'
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "active_support/core_ext/class/attribute"
 
 class ClassAttributeTest < ActiveSupport::TestCase
   def setup
-    @klass = Class.new { class_attribute :setting }
+    @klass = Class.new do
+      class_attribute :setting
+      class_attribute :timeout, default: 5
+    end
+
     @sub = Class.new(@klass)
   end
 
-  test 'defaults to nil' do
+  test "defaults to nil" do
     assert_nil @klass.setting
     assert_nil @sub.setting
   end
 
-  test 'inheritable' do
+  test "custom default" do
+    assert_equal 5, @klass.timeout
+  end
+
+  test "inheritable" do
     @klass.setting = 1
     assert_equal 1, @sub.setting
   end
 
-  test 'overridable' do
+  test "overridable" do
     @sub.setting = 1
     assert_nil @klass.setting
 
@@ -27,20 +37,20 @@ class ClassAttributeTest < ActiveSupport::TestCase
     assert_equal 1, Class.new(@sub).setting
   end
 
-  test 'predicate method' do
+  test "predicate method" do
     assert_equal false, @klass.setting?
     @klass.setting = 1
     assert_equal true, @klass.setting?
   end
 
-  test 'instance reader delegates to class' do
+  test "instance reader delegates to class" do
     assert_nil @klass.new.setting
 
     @klass.setting = 1
     assert_equal 1, @klass.new.setting
   end
 
-  test 'instance override' do
+  test "instance override" do
     object = @klass.new
     object.setting = 1
     assert_nil @klass.setting
@@ -48,43 +58,43 @@ class ClassAttributeTest < ActiveSupport::TestCase
     assert_equal 1, object.setting
   end
 
-  test 'instance predicate' do
+  test "instance predicate" do
     object = @klass.new
     assert_equal false, object.setting?
     object.setting = 1
     assert_equal true, object.setting?
   end
 
-  test 'disabling instance writer' do
-    object = Class.new { class_attribute :setting, :instance_writer => false }.new
-    assert_raise(NoMethodError) { object.setting = 'boom' }
+  test "disabling instance writer" do
+    object = Class.new { class_attribute :setting, instance_writer: false }.new
+    assert_raise(NoMethodError) { object.setting = "boom" }
   end
 
-  test 'disabling instance reader' do
-    object = Class.new { class_attribute :setting, :instance_reader => false }.new
+  test "disabling instance reader" do
+    object = Class.new { class_attribute :setting, instance_reader: false }.new
     assert_raise(NoMethodError) { object.setting }
     assert_raise(NoMethodError) { object.setting? }
   end
 
-  test 'disabling both instance writer and reader' do
-    object = Class.new { class_attribute :setting, :instance_accessor => false }.new
+  test "disabling both instance writer and reader" do
+    object = Class.new { class_attribute :setting, instance_accessor: false }.new
     assert_raise(NoMethodError) { object.setting }
     assert_raise(NoMethodError) { object.setting? }
-    assert_raise(NoMethodError) { object.setting = 'boom' }
+    assert_raise(NoMethodError) { object.setting = "boom" }
   end
 
-  test 'disabling instance predicate' do
+  test "disabling instance predicate" do
     object = Class.new { class_attribute :setting, instance_predicate: false }.new
     assert_raise(NoMethodError) { object.setting? }
   end
 
-  test 'works well with singleton classes' do
+  test "works well with singleton classes" do
     object = @klass.new
-    object.singleton_class.setting = 'foo'
-    assert_equal 'foo', object.setting
+    object.singleton_class.setting = "foo"
+    assert_equal "foo", object.setting
   end
 
-  test 'setter returns set value' do
+  test "setter returns set value" do
     val = @klass.send(:setting=, 1)
     assert_equal 1, val
   end
diff --git a/activesupport/test/core_ext/class_test.rb b/activesupport/test/core_ext/class_test.rb
index 9c6c579ef7..9cc006fc63 100644
--- a/activesupport/test/core_ext/class_test.rb
+++ b/activesupport/test/core_ext/class_test.rb
@@ -1,6 +1,8 @@
-require 'abstract_unit'
-require 'active_support/core_ext/class'
-require 'set'
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "active_support/core_ext/class"
+require "set"
 
 class ClassTest < ActiveSupport::TestCase
   class Parent; end
@@ -25,4 +27,14 @@ class ClassTest < ActiveSupport::TestCase
     assert_equal [Baz], Bar.subclasses
     assert_equal [], Baz.subclasses
   end
+
+  def test_descendants_excludes_singleton_classes
+    klass = Parent.new.singleton_class
+    refute Parent.descendants.include?(klass), "descendants should not include singleton classes"
+  end
+
+  def test_subclasses_excludes_singleton_classes
+    klass = Parent.new.singleton_class
+    refute Parent.subclasses.include?(klass), "subclasses should not include singleton classes"
+  end
 end
diff --git a/activesupport/test/core_ext/date_and_time_behavior.rb b/activesupport/test/core_ext/date_and_time_behavior.rb
index 54df87def8..1176ed647a 100644
--- a/activesupport/test/core_ext/date_and_time_behavior.rb
+++ b/activesupport/test/core_ext/date_and_time_behavior.rb
@@ -1,107 +1,119 @@
-require 'abstract_unit'
+# frozen_string_literal: true
+
+require "abstract_unit"
 
 module DateAndTimeBehavior
   def test_yesterday
-    assert_equal date_time_init(2005,2,21,10,10,10), date_time_init(2005,2,22,10,10,10).yesterday
-    assert_equal date_time_init(2005,2,28,10,10,10), date_time_init(2005,3,2,10,10,10).yesterday.yesterday
+    assert_equal date_time_init(2005, 2, 21, 10, 10, 10), date_time_init(2005, 2, 22, 10, 10, 10).yesterday
+    assert_equal date_time_init(2005, 2, 28, 10, 10, 10), date_time_init(2005, 3, 2, 10, 10, 10).yesterday.yesterday
   end
 
   def test_prev_day
-    assert_equal date_time_init(2005,2,21,10,10,10), date_time_init(2005,2,22,10,10,10).prev_day
-    assert_equal date_time_init(2005,2,28,10,10,10), date_time_init(2005,3,2,10,10,10).prev_day.prev_day
+    assert_equal date_time_init(2005, 2, 24, 10, 10, 10), date_time_init(2005, 2, 22, 10, 10, 10).prev_day(-2)
+    assert_equal date_time_init(2005, 2, 23, 10, 10, 10), date_time_init(2005, 2, 22, 10, 10, 10).prev_day(-1)
+    assert_equal date_time_init(2005, 2, 22, 10, 10, 10), date_time_init(2005, 2, 22, 10, 10, 10).prev_day(0)
+    assert_equal date_time_init(2005, 2, 21, 10, 10, 10), date_time_init(2005, 2, 22, 10, 10, 10).prev_day(1)
+    assert_equal date_time_init(2005, 2, 20, 10, 10, 10), date_time_init(2005, 2, 22, 10, 10, 10).prev_day(2)
+    assert_equal date_time_init(2005, 2, 21, 10, 10, 10), date_time_init(2005, 2, 22, 10, 10, 10).prev_day
+    assert_equal date_time_init(2005, 2, 28, 10, 10, 10), date_time_init(2005, 3, 2, 10, 10, 10).prev_day.prev_day
   end
 
   def test_tomorrow
-    assert_equal date_time_init(2005,2,23,10,10,10), date_time_init(2005,2,22,10,10,10).tomorrow
-    assert_equal date_time_init(2005,3,2,10,10,10),  date_time_init(2005,2,28,10,10,10).tomorrow.tomorrow
+    assert_equal date_time_init(2005, 2, 23, 10, 10, 10), date_time_init(2005, 2, 22, 10, 10, 10).tomorrow
+    assert_equal date_time_init(2005, 3, 2, 10, 10, 10),  date_time_init(2005, 2, 28, 10, 10, 10).tomorrow.tomorrow
   end
 
   def test_next_day
-    assert_equal date_time_init(2005,2,23,10,10,10), date_time_init(2005,2,22,10,10,10).next_day
-    assert_equal date_time_init(2005,3,2,10,10,10),  date_time_init(2005,2,28,10,10,10).next_day.next_day
+    assert_equal date_time_init(2005, 2, 20, 10, 10, 10), date_time_init(2005, 2, 22, 10, 10, 10).next_day(-2)
+    assert_equal date_time_init(2005, 2, 21, 10, 10, 10), date_time_init(2005, 2, 22, 10, 10, 10).next_day(-1)
+    assert_equal date_time_init(2005, 2, 22, 10, 10, 10), date_time_init(2005, 2, 22, 10, 10, 10).next_day(0)
+    assert_equal date_time_init(2005, 2, 23, 10, 10, 10), date_time_init(2005, 2, 22, 10, 10, 10).next_day(1)
+    assert_equal date_time_init(2005, 2, 24, 10, 10, 10), date_time_init(2005, 2, 22, 10, 10, 10).next_day(2)
+    assert_equal date_time_init(2005, 2, 23, 10, 10, 10), date_time_init(2005, 2, 22, 10, 10, 10).next_day
+    assert_equal date_time_init(2005, 3, 2, 10, 10, 10),  date_time_init(2005, 2, 28, 10, 10, 10).next_day.next_day
   end
 
   def test_days_ago
-    assert_equal date_time_init(2005,6,4,10,10,10),  date_time_init(2005,6,5,10,10,10).days_ago(1)
-    assert_equal date_time_init(2005,5,31,10,10,10),   date_time_init(2005,6,5,10,10,10).days_ago(5)
+    assert_equal date_time_init(2005, 6, 4, 10, 10, 10),  date_time_init(2005, 6, 5, 10, 10, 10).days_ago(1)
+    assert_equal date_time_init(2005, 5, 31, 10, 10, 10),   date_time_init(2005, 6, 5, 10, 10, 10).days_ago(5)
   end
 
   def test_days_since
-    assert_equal date_time_init(2005,6,6,10,10,10),  date_time_init(2005,6,5,10,10,10).days_since(1)
-    assert_equal date_time_init(2005,1,1,10,10,10), date_time_init(2004,12,31,10,10,10).days_since(1)
+    assert_equal date_time_init(2005, 6, 6, 10, 10, 10),  date_time_init(2005, 6, 5, 10, 10, 10).days_since(1)
+    assert_equal date_time_init(2005, 1, 1, 10, 10, 10), date_time_init(2004, 12, 31, 10, 10, 10).days_since(1)
   end
 
   def test_weeks_ago
-    assert_equal date_time_init(2005,5,29,10,10,10),  date_time_init(2005,6,5,10,10,10).weeks_ago(1)
-    assert_equal date_time_init(2005,5,1,10,10,10),   date_time_init(2005,6,5,10,10,10).weeks_ago(5)
-    assert_equal date_time_init(2005,4,24,10,10,10),  date_time_init(2005,6,5,10,10,10).weeks_ago(6)
-    assert_equal date_time_init(2005,2,27,10,10,10),  date_time_init(2005,6,5,10,10,10).weeks_ago(14)
-    assert_equal date_time_init(2004,12,25,10,10,10), date_time_init(2005,1,1,10,10,10).weeks_ago(1)
+    assert_equal date_time_init(2005, 5, 29, 10, 10, 10),  date_time_init(2005, 6, 5, 10, 10, 10).weeks_ago(1)
+    assert_equal date_time_init(2005, 5, 1, 10, 10, 10),   date_time_init(2005, 6, 5, 10, 10, 10).weeks_ago(5)
+    assert_equal date_time_init(2005, 4, 24, 10, 10, 10),  date_time_init(2005, 6, 5, 10, 10, 10).weeks_ago(6)
+    assert_equal date_time_init(2005, 2, 27, 10, 10, 10),  date_time_init(2005, 6, 5, 10, 10, 10).weeks_ago(14)
+    assert_equal date_time_init(2004, 12, 25, 10, 10, 10), date_time_init(2005, 1, 1, 10, 10, 10).weeks_ago(1)
   end
 
   def test_weeks_since
-    assert_equal date_time_init(2005,7,14,10,10,10), date_time_init(2005,7,7,10,10,10).weeks_since(1)
-    assert_equal date_time_init(2005,7,14,10,10,10), date_time_init(2005,7,7,10,10,10).weeks_since(1)
-    assert_equal date_time_init(2005,7,4,10,10,10),  date_time_init(2005,6,27,10,10,10).weeks_since(1)
-    assert_equal date_time_init(2005,1,4,10,10,10),  date_time_init(2004,12,28,10,10,10).weeks_since(1)
+    assert_equal date_time_init(2005, 7, 14, 10, 10, 10), date_time_init(2005, 7, 7, 10, 10, 10).weeks_since(1)
+    assert_equal date_time_init(2005, 7, 14, 10, 10, 10), date_time_init(2005, 7, 7, 10, 10, 10).weeks_since(1)
+    assert_equal date_time_init(2005, 7, 4, 10, 10, 10),  date_time_init(2005, 6, 27, 10, 10, 10).weeks_since(1)
+    assert_equal date_time_init(2005, 1, 4, 10, 10, 10),  date_time_init(2004, 12, 28, 10, 10, 10).weeks_since(1)
   end
 
   def test_months_ago
-    assert_equal date_time_init(2005,5,5,10,10,10),  date_time_init(2005,6,5,10,10,10).months_ago(1)
-    assert_equal date_time_init(2004,11,5,10,10,10), date_time_init(2005,6,5,10,10,10).months_ago(7)
-    assert_equal date_time_init(2004,12,5,10,10,10), date_time_init(2005,6,5,10,10,10).months_ago(6)
-    assert_equal date_time_init(2004,6,5,10,10,10),  date_time_init(2005,6,5,10,10,10).months_ago(12)
-    assert_equal date_time_init(2003,6,5,10,10,10),  date_time_init(2005,6,5,10,10,10).months_ago(24)
+    assert_equal date_time_init(2005, 5, 5, 10, 10, 10),  date_time_init(2005, 6, 5, 10, 10, 10).months_ago(1)
+    assert_equal date_time_init(2004, 11, 5, 10, 10, 10), date_time_init(2005, 6, 5, 10, 10, 10).months_ago(7)
+    assert_equal date_time_init(2004, 12, 5, 10, 10, 10), date_time_init(2005, 6, 5, 10, 10, 10).months_ago(6)
+    assert_equal date_time_init(2004, 6, 5, 10, 10, 10),  date_time_init(2005, 6, 5, 10, 10, 10).months_ago(12)
+    assert_equal date_time_init(2003, 6, 5, 10, 10, 10),  date_time_init(2005, 6, 5, 10, 10, 10).months_ago(24)
   end
 
   def test_months_since
-    assert_equal date_time_init(2005,7,5,10,10,10),   date_time_init(2005,6,5,10,10,10).months_since(1)
-    assert_equal date_time_init(2006,1,5,10,10,10),   date_time_init(2005,12,5,10,10,10).months_since(1)
-    assert_equal date_time_init(2005,12,5,10,10,10),  date_time_init(2005,6,5,10,10,10).months_since(6)
-    assert_equal date_time_init(2006,6,5,10,10,10),   date_time_init(2005,12,5,10,10,10).months_since(6)
-    assert_equal date_time_init(2006,1,5,10,10,10),   date_time_init(2005,6,5,10,10,10).months_since(7)
-    assert_equal date_time_init(2006,6,5,10,10,10),   date_time_init(2005,6,5,10,10,10).months_since(12)
-    assert_equal date_time_init(2007,6,5,10,10,10),   date_time_init(2005,6,5,10,10,10).months_since(24)
-    assert_equal date_time_init(2005,4,30,10,10,10),  date_time_init(2005,3,31,10,10,10).months_since(1)
-    assert_equal date_time_init(2005,2,28,10,10,10),  date_time_init(2005,1,29,10,10,10).months_since(1)
-    assert_equal date_time_init(2005,2,28,10,10,10),  date_time_init(2005,1,30,10,10,10).months_since(1)
-    assert_equal date_time_init(2005,2,28,10,10,10),  date_time_init(2005,1,31,10,10,10).months_since(1)
+    assert_equal date_time_init(2005, 7, 5, 10, 10, 10),   date_time_init(2005, 6, 5, 10, 10, 10).months_since(1)
+    assert_equal date_time_init(2006, 1, 5, 10, 10, 10),   date_time_init(2005, 12, 5, 10, 10, 10).months_since(1)
+    assert_equal date_time_init(2005, 12, 5, 10, 10, 10),  date_time_init(2005, 6, 5, 10, 10, 10).months_since(6)
+    assert_equal date_time_init(2006, 6, 5, 10, 10, 10),   date_time_init(2005, 12, 5, 10, 10, 10).months_since(6)
+    assert_equal date_time_init(2006, 1, 5, 10, 10, 10),   date_time_init(2005, 6, 5, 10, 10, 10).months_since(7)
+    assert_equal date_time_init(2006, 6, 5, 10, 10, 10),   date_time_init(2005, 6, 5, 10, 10, 10).months_since(12)
+    assert_equal date_time_init(2007, 6, 5, 10, 10, 10),   date_time_init(2005, 6, 5, 10, 10, 10).months_since(24)
+    assert_equal date_time_init(2005, 4, 30, 10, 10, 10),  date_time_init(2005, 3, 31, 10, 10, 10).months_since(1)
+    assert_equal date_time_init(2005, 2, 28, 10, 10, 10),  date_time_init(2005, 1, 29, 10, 10, 10).months_since(1)
+    assert_equal date_time_init(2005, 2, 28, 10, 10, 10),  date_time_init(2005, 1, 30, 10, 10, 10).months_since(1)
+    assert_equal date_time_init(2005, 2, 28, 10, 10, 10),  date_time_init(2005, 1, 31, 10, 10, 10).months_since(1)
   end
 
   def test_years_ago
-    assert_equal date_time_init(2004,6,5,10,10,10),  date_time_init(2005,6,5,10,10,10).years_ago(1)
-    assert_equal date_time_init(1998,6,5,10,10,10),  date_time_init(2005,6,5,10,10,10).years_ago(7)
-    assert_equal date_time_init(2003,2,28,10,10,10), date_time_init(2004,2,29,10,10,10).years_ago(1) # 1 year ago from leap day
+    assert_equal date_time_init(2004, 6, 5, 10, 10, 10),  date_time_init(2005, 6, 5, 10, 10, 10).years_ago(1)
+    assert_equal date_time_init(1998, 6, 5, 10, 10, 10),  date_time_init(2005, 6, 5, 10, 10, 10).years_ago(7)
+    assert_equal date_time_init(2003, 2, 28, 10, 10, 10), date_time_init(2004, 2, 29, 10, 10, 10).years_ago(1) # 1 year ago from leap day
   end
 
   def test_years_since
-    assert_equal date_time_init(2006,6,5,10,10,10),  date_time_init(2005,6,5,10,10,10).years_since(1)
-    assert_equal date_time_init(2012,6,5,10,10,10),  date_time_init(2005,6,5,10,10,10).years_since(7)
-    assert_equal date_time_init(2005,2,28,10,10,10), date_time_init(2004,2,29,10,10,10).years_since(1) # 1 year since leap day
-    assert_equal date_time_init(2182,6,5,10,10,10),  date_time_init(2005,6,5,10,10,10).years_since(177)
+    assert_equal date_time_init(2006, 6, 5, 10, 10, 10),  date_time_init(2005, 6, 5, 10, 10, 10).years_since(1)
+    assert_equal date_time_init(2012, 6, 5, 10, 10, 10),  date_time_init(2005, 6, 5, 10, 10, 10).years_since(7)
+    assert_equal date_time_init(2005, 2, 28, 10, 10, 10), date_time_init(2004, 2, 29, 10, 10, 10).years_since(1) # 1 year since leap day
+    assert_equal date_time_init(2182, 6, 5, 10, 10, 10),  date_time_init(2005, 6, 5, 10, 10, 10).years_since(177)
   end
 
   def test_beginning_of_month
-    assert_equal date_time_init(2005,2,1,0,0,0), date_time_init(2005,2,22,10,10,10).beginning_of_month
+    assert_equal date_time_init(2005, 2, 1, 0, 0, 0), date_time_init(2005, 2, 22, 10, 10, 10).beginning_of_month
   end
 
   def test_beginning_of_quarter
-    assert_equal date_time_init(2005,1,1,0,0,0),  date_time_init(2005,2,15,10,10,10).beginning_of_quarter
-    assert_equal date_time_init(2005,1,1,0,0,0),  date_time_init(2005,1,1,0,0,0).beginning_of_quarter
-    assert_equal date_time_init(2005,10,1,0,0,0), date_time_init(2005,12,31,10,10,10).beginning_of_quarter
-    assert_equal date_time_init(2005,4,1,0,0,0),  date_time_init(2005,6,30,23,59,59).beginning_of_quarter
+    assert_equal date_time_init(2005, 1, 1, 0, 0, 0),  date_time_init(2005, 2, 15, 10, 10, 10).beginning_of_quarter
+    assert_equal date_time_init(2005, 1, 1, 0, 0, 0),  date_time_init(2005, 1, 1, 0, 0, 0).beginning_of_quarter
+    assert_equal date_time_init(2005, 10, 1, 0, 0, 0), date_time_init(2005, 12, 31, 10, 10, 10).beginning_of_quarter
+    assert_equal date_time_init(2005, 4, 1, 0, 0, 0),  date_time_init(2005, 6, 30, 23, 59, 59).beginning_of_quarter
   end
 
   def test_end_of_quarter
-    assert_equal date_time_init(2007,3,31,23,59,59,Rational(999999999, 1000)), date_time_init(2007,2,15,10,10,10).end_of_quarter
-    assert_equal date_time_init(2007,3,31,23,59,59,Rational(999999999, 1000)), date_time_init(2007,3,31,0,0,0).end_of_quarter
-    assert_equal date_time_init(2007,12,31,23,59,59,Rational(999999999, 1000)), date_time_init(2007,12,21,10,10,10).end_of_quarter
-    assert_equal date_time_init(2007,6,30,23,59,59,Rational(999999999, 1000)), date_time_init(2007,4,1,0,0,0).end_of_quarter
-    assert_equal date_time_init(2008,6,30,23,59,59,Rational(999999999, 1000)), date_time_init(2008,5,31,0,0,0).end_of_quarter
+    assert_equal date_time_init(2007, 3, 31, 23, 59, 59, Rational(999999999, 1000)), date_time_init(2007, 2, 15, 10, 10, 10).end_of_quarter
+    assert_equal date_time_init(2007, 3, 31, 23, 59, 59, Rational(999999999, 1000)), date_time_init(2007, 3, 31, 0, 0, 0).end_of_quarter
+    assert_equal date_time_init(2007, 12, 31, 23, 59, 59, Rational(999999999, 1000)), date_time_init(2007, 12, 21, 10, 10, 10).end_of_quarter
+    assert_equal date_time_init(2007, 6, 30, 23, 59, 59, Rational(999999999, 1000)), date_time_init(2007, 4, 1, 0, 0, 0).end_of_quarter
+    assert_equal date_time_init(2008, 6, 30, 23, 59, 59, Rational(999999999, 1000)), date_time_init(2008, 5, 31, 0, 0, 0).end_of_quarter
   end
 
   def test_beginning_of_year
-    assert_equal date_time_init(2005,1,1,0,0,0), date_time_init(2005,2,22,10,10,10).beginning_of_year
+    assert_equal date_time_init(2005, 1, 1, 0, 0, 0), date_time_init(2005, 2, 22, 10, 10, 10).beginning_of_year
   end
 
   def test_next_week
@@ -110,10 +122,10 @@ module DateAndTimeBehavior
     #       | 22/2 |   |   |   |   |   #       |   |       |   | 4/3 |   |   # friday in next week `next_week(:friday)`
     # 23/10 |      |   |   |   |   |   # 30/10 |   |       |   |     |   |   # monday in next week `next_week`
     # 23/10 |      |   |   |   |   |   #       |   |  1/11 |   |     |   |   # wednesday in next week `next_week(:wednesday)`
-    assert_equal date_time_init(2005,2,28,0,0,0),  date_time_init(2005,2,22,15,15,10).next_week
-    assert_equal date_time_init(2005,3,4,0,0,0),   date_time_init(2005,2,22,15,15,10).next_week(:friday)
-    assert_equal date_time_init(2006,10,30,0,0,0), date_time_init(2006,10,23,0,0,0).next_week
-    assert_equal date_time_init(2006,11,1,0,0,0),  date_time_init(2006,10,23,0,0,0).next_week(:wednesday)
+    assert_equal date_time_init(2005, 2, 28, 0, 0, 0),  date_time_init(2005, 2, 22, 15, 15, 10).next_week
+    assert_equal date_time_init(2005, 3, 4, 0, 0, 0),   date_time_init(2005, 2, 22, 15, 15, 10).next_week(:friday)
+    assert_equal date_time_init(2006, 10, 30, 0, 0, 0), date_time_init(2006, 10, 23, 0, 0, 0).next_week
+    assert_equal date_time_init(2006, 11, 1, 0, 0, 0),  date_time_init(2006, 10, 23, 0, 0, 0).next_week(:wednesday)
   end
 
   def test_next_week_with_default_beginning_of_week_set
@@ -126,45 +138,63 @@ module DateAndTimeBehavior
   end
 
   def test_next_week_at_same_time
-    assert_equal date_time_init(2005,2,28,15,15,10),  date_time_init(2005,2,22,15,15,10).next_week(:monday, same_time: true)
-    assert_equal date_time_init(2005,3,4,15,15,10),   date_time_init(2005,2,22,15,15,10).next_week(:friday, same_time: true)
-    assert_equal date_time_init(2006,10,30,0,0,0), date_time_init(2006,10,23,0,0,0).next_week(:monday, same_time: true)
-    assert_equal date_time_init(2006,11,1,0,0,0),  date_time_init(2006,10,23,0,0,0).next_week(:wednesday, same_time: true)
+    assert_equal date_time_init(2005, 2, 28, 15, 15, 10), date_time_init(2005, 2, 22, 15, 15, 10).next_week(:monday, same_time: true)
+    assert_equal date_time_init(2005, 2, 28, 15, 15, 10, 999999), date_time_init(2005, 2, 22, 15, 15, 10, 999999).next_week(:monday, same_time: true)
+    assert_equal date_time_init(2005, 2, 28, 15, 15, 10, Rational(999999999, 1000)), date_time_init(2005, 2, 22, 15, 15, 10, Rational(999999999, 1000)).next_week(:monday, same_time: true)
+    assert_equal date_time_init(2005, 3, 4, 15, 15, 10),   date_time_init(2005, 2, 22, 15, 15, 10).next_week(:friday, same_time: true)
+    assert_equal date_time_init(2006, 10, 30, 0, 0, 0), date_time_init(2006, 10, 23, 0, 0, 0).next_week(:monday, same_time: true)
+    assert_equal date_time_init(2006, 11, 1, 0, 0, 0),  date_time_init(2006, 10, 23, 0, 0, 0).next_week(:wednesday, same_time: true)
   end
 
   def test_next_weekday_on_wednesday
-    assert_equal date_time_init(2015,1,8,0,0,0), date_time_init(2015,1,7,0,0,0).next_weekday
-    assert_equal date_time_init(2015,1,8,15,15,10), date_time_init(2015,1,7,15,15,10).next_weekday
+    assert_equal date_time_init(2015, 1, 8, 0, 0, 0), date_time_init(2015, 1, 7, 0, 0, 0).next_weekday
+    assert_equal date_time_init(2015, 1, 8, 15, 15, 10), date_time_init(2015, 1, 7, 15, 15, 10).next_weekday
   end
 
   def test_next_weekday_on_friday
-    assert_equal date_time_init(2015,1,5,0,0,0), date_time_init(2015,1,2,0,0,0).next_weekday
-    assert_equal date_time_init(2015,1,5,15,15,10), date_time_init(2015,1,2,15,15,10).next_weekday
+    assert_equal date_time_init(2015, 1, 5, 0, 0, 0), date_time_init(2015, 1, 2, 0, 0, 0).next_weekday
+    assert_equal date_time_init(2015, 1, 5, 15, 15, 10), date_time_init(2015, 1, 2, 15, 15, 10).next_weekday
   end
 
   def test_next_weekday_on_saturday
-    assert_equal date_time_init(2015,1,5,0,0,0), date_time_init(2015,1,3,0,0,0).next_weekday
-    assert_equal date_time_init(2015,1,5,15,15,10), date_time_init(2015,1,3,15,15,10).next_weekday
+    assert_equal date_time_init(2015, 1, 5, 0, 0, 0), date_time_init(2015, 1, 3, 0, 0, 0).next_weekday
+    assert_equal date_time_init(2015, 1, 5, 15, 15, 10), date_time_init(2015, 1, 3, 15, 15, 10).next_weekday
+  end
+
+  def test_next_month
+    assert_equal date_time_init(2004, 12, 22, 10, 10, 10), date_time_init(2005, 2, 22, 10, 10, 10).next_month(-2)
+    assert_equal date_time_init(2005, 1, 22, 10, 10, 10), date_time_init(2005, 2, 22, 10, 10, 10).next_month(-1)
+    assert_equal date_time_init(2005, 2, 22, 10, 10, 10), date_time_init(2005, 2, 22, 10, 10, 10).next_month(0)
+    assert_equal date_time_init(2005, 3, 22, 10, 10, 10), date_time_init(2005, 2, 22, 10, 10, 10).next_month(1)
+    assert_equal date_time_init(2005, 4, 22, 10, 10, 10), date_time_init(2005, 2, 22, 10, 10, 10).next_month(2)
+    assert_equal date_time_init(2005, 3, 22, 10, 10, 10), date_time_init(2005, 2, 22, 10, 10, 10).next_month
+    assert_equal date_time_init(2005, 4, 22, 10, 10, 10), date_time_init(2005, 2, 22, 10, 10, 10).next_month.next_month
   end
 
   def test_next_month_on_31st
-    assert_equal date_time_init(2005,9,30,15,15,10), date_time_init(2005,8,31,15,15,10).next_month
+    assert_equal date_time_init(2005, 9, 30, 15, 15, 10), date_time_init(2005, 8, 31, 15, 15, 10).next_month
   end
 
   def test_next_quarter_on_31st
-    assert_equal date_time_init(2005,11,30,15,15,10), date_time_init(2005,8,31,15,15,10).next_quarter
+    assert_equal date_time_init(2005, 11, 30, 15, 15, 10), date_time_init(2005, 8, 31, 15, 15, 10).next_quarter
   end
 
   def test_next_year
-    assert_equal date_time_init(2006,6,5,10,10,10), date_time_init(2005,6,5,10,10,10).next_year
+    assert_equal date_time_init(2003, 6, 5, 10, 10, 10), date_time_init(2005, 6, 5, 10, 10, 10).next_year(-2)
+    assert_equal date_time_init(2004, 6, 5, 10, 10, 10), date_time_init(2005, 6, 5, 10, 10, 10).next_year(-1)
+    assert_equal date_time_init(2005, 6, 5, 10, 10, 10), date_time_init(2005, 6, 5, 10, 10, 10).next_year(0)
+    assert_equal date_time_init(2006, 6, 5, 10, 10, 10), date_time_init(2005, 6, 5, 10, 10, 10).next_year(1)
+    assert_equal date_time_init(2007, 6, 5, 10, 10, 10), date_time_init(2005, 6, 5, 10, 10, 10).next_year(2)
+    assert_equal date_time_init(2006, 6, 5, 10, 10, 10), date_time_init(2005, 6, 5, 10, 10, 10).next_year
+    assert_equal date_time_init(2007, 6, 5, 10, 10, 10), date_time_init(2005, 6, 5, 10, 10, 10).next_year.next_year
   end
 
   def test_prev_week
-    assert_equal date_time_init(2005,2,21,0,0,0),  date_time_init(2005,3,1,15,15,10).prev_week
-    assert_equal date_time_init(2005,2,22,0,0,0),  date_time_init(2005,3,1,15,15,10).prev_week(:tuesday)
-    assert_equal date_time_init(2005,2,25,0,0,0),  date_time_init(2005,3,1,15,15,10).prev_week(:friday)
-    assert_equal date_time_init(2006,10,30,0,0,0), date_time_init(2006,11,6,0,0,0).prev_week
-    assert_equal date_time_init(2006,11,15,0,0,0), date_time_init(2006,11,23,0,0,0).prev_week(:wednesday)
+    assert_equal date_time_init(2005, 2, 21, 0, 0, 0),  date_time_init(2005, 3, 1, 15, 15, 10).prev_week
+    assert_equal date_time_init(2005, 2, 22, 0, 0, 0),  date_time_init(2005, 3, 1, 15, 15, 10).prev_week(:tuesday)
+    assert_equal date_time_init(2005, 2, 25, 0, 0, 0),  date_time_init(2005, 3, 1, 15, 15, 10).prev_week(:friday)
+    assert_equal date_time_init(2006, 10, 30, 0, 0, 0), date_time_init(2006, 11, 6, 0, 0, 0).prev_week
+    assert_equal date_time_init(2006, 11, 15, 0, 0, 0), date_time_init(2006, 11, 23, 0, 0, 0).prev_week(:wednesday)
   end
 
   def test_prev_week_with_default_beginning_of_week
@@ -177,138 +207,182 @@ module DateAndTimeBehavior
   end
 
   def test_prev_week_at_same_time
-    assert_equal date_time_init(2005,2,21,15,15,10),  date_time_init(2005,3,1,15,15,10).prev_week(:monday, same_time: true)
-    assert_equal date_time_init(2005,2,22,15,15,10),  date_time_init(2005,3,1,15,15,10).prev_week(:tuesday, same_time: true)
-    assert_equal date_time_init(2005,2,25,15,15,10),  date_time_init(2005,3,1,15,15,10).prev_week(:friday, same_time: true)
-    assert_equal date_time_init(2006,10,30,0,0,0), date_time_init(2006,11,6,0,0,0).prev_week(:monday, same_time: true)
-    assert_equal date_time_init(2006,11,15,0,0,0), date_time_init(2006,11,23,0,0,0).prev_week(:wednesday, same_time: true)
+    assert_equal date_time_init(2005, 2, 21, 15, 15, 10),  date_time_init(2005, 3, 1, 15, 15, 10).prev_week(:monday, same_time: true)
+    assert_equal date_time_init(2005, 2, 22, 15, 15, 10),  date_time_init(2005, 3, 1, 15, 15, 10).prev_week(:tuesday, same_time: true)
+    assert_equal date_time_init(2005, 2, 25, 15, 15, 10),  date_time_init(2005, 3, 1, 15, 15, 10).prev_week(:friday, same_time: true)
+    assert_equal date_time_init(2006, 10, 30, 0, 0, 0), date_time_init(2006, 11, 6, 0, 0, 0).prev_week(:monday, same_time: true)
+    assert_equal date_time_init(2006, 11, 15, 0, 0, 0), date_time_init(2006, 11, 23, 0, 0, 0).prev_week(:wednesday, same_time: true)
   end
 
   def test_prev_weekday_on_wednesday
-    assert_equal date_time_init(2015,1,6,0,0,0), date_time_init(2015,1,7,0,0,0).prev_weekday
-    assert_equal date_time_init(2015,1,6,15,15,10), date_time_init(2015,1,7,15,15,10).prev_weekday
+    assert_equal date_time_init(2015, 1, 6, 0, 0, 0), date_time_init(2015, 1, 7, 0, 0, 0).prev_weekday
+    assert_equal date_time_init(2015, 1, 6, 15, 15, 10), date_time_init(2015, 1, 7, 15, 15, 10).prev_weekday
   end
 
   def test_prev_weekday_on_monday
-    assert_equal date_time_init(2015,1,2,0,0,0), date_time_init(2015,1,5,0,0,0).prev_weekday
-    assert_equal date_time_init(2015,1,2,15,15,10), date_time_init(2015,1,5,15,15,10).prev_weekday
+    assert_equal date_time_init(2015, 1, 2, 0, 0, 0), date_time_init(2015, 1, 5, 0, 0, 0).prev_weekday
+    assert_equal date_time_init(2015, 1, 2, 15, 15, 10), date_time_init(2015, 1, 5, 15, 15, 10).prev_weekday
   end
 
   def test_prev_weekday_on_sunday
-    assert_equal date_time_init(2015,1,2,0,0,0), date_time_init(2015,1,4,0,0,0).prev_weekday
-    assert_equal date_time_init(2015,1,2,15,15,10), date_time_init(2015,1,4,15,15,10).prev_weekday
+    assert_equal date_time_init(2015, 1, 2, 0, 0, 0), date_time_init(2015, 1, 4, 0, 0, 0).prev_weekday
+    assert_equal date_time_init(2015, 1, 2, 15, 15, 10), date_time_init(2015, 1, 4, 15, 15, 10).prev_weekday
+  end
+
+  def test_prev_month
+    assert_equal date_time_init(2005, 4, 22, 10, 10, 10), date_time_init(2005, 2, 22, 10, 10, 10).prev_month(-2)
+    assert_equal date_time_init(2005, 3, 22, 10, 10, 10), date_time_init(2005, 2, 22, 10, 10, 10).prev_month(-1)
+    assert_equal date_time_init(2005, 2, 22, 10, 10, 10), date_time_init(2005, 2, 22, 10, 10, 10).prev_month(0)
+    assert_equal date_time_init(2005, 1, 22, 10, 10, 10), date_time_init(2005, 2, 22, 10, 10, 10).prev_month(1)
+    assert_equal date_time_init(2004, 12, 22, 10, 10, 10), date_time_init(2005, 2, 22, 10, 10, 10).prev_month(2)
+    assert_equal date_time_init(2005, 1, 22, 10, 10, 10), date_time_init(2005, 2, 22, 10, 10, 10).prev_month
+    assert_equal date_time_init(2004, 12, 22, 10, 10, 10), date_time_init(2005, 2, 22, 10, 10, 10).prev_month.prev_month
   end
 
   def test_prev_month_on_31st
-    assert_equal date_time_init(2004,2,29,10,10,10), date_time_init(2004,3,31,10,10,10).prev_month
+    assert_equal date_time_init(2004, 2, 29, 10, 10, 10), date_time_init(2004, 3, 31, 10, 10, 10).prev_month
   end
 
   def test_prev_quarter_on_31st
-    assert_equal date_time_init(2004,2,29,10,10,10), date_time_init(2004,5,31,10,10,10).prev_quarter
+    assert_equal date_time_init(2004, 2, 29, 10, 10, 10), date_time_init(2004, 5, 31, 10, 10, 10).prev_quarter
   end
 
   def test_prev_year
-    assert_equal date_time_init(2004,6,5,10,10,10),  date_time_init(2005,6,5,10,10,10).prev_year
+    assert_equal date_time_init(2007, 6, 5, 10, 10, 10),  date_time_init(2005, 6, 5, 10, 10, 10).prev_year(-2)
+    assert_equal date_time_init(2006, 6, 5, 10, 10, 10),  date_time_init(2005, 6, 5, 10, 10, 10).prev_year(-1)
+    assert_equal date_time_init(2005, 6, 5, 10, 10, 10),  date_time_init(2005, 6, 5, 10, 10, 10).prev_year(0)
+    assert_equal date_time_init(2004, 6, 5, 10, 10, 10),  date_time_init(2005, 6, 5, 10, 10, 10).prev_year(1)
+    assert_equal date_time_init(2003, 6, 5, 10, 10, 10),  date_time_init(2005, 6, 5, 10, 10, 10).prev_year(2)
+    assert_equal date_time_init(2004, 6, 5, 10, 10, 10),  date_time_init(2005, 6, 5, 10, 10, 10).prev_year
+    assert_equal date_time_init(2003, 6, 5, 10, 10, 10),  date_time_init(2005, 6, 5, 10, 10, 10).prev_year.prev_year
+  end
+
+  def test_last_month_on_31st
+    assert_equal date_time_init(2004, 2, 29, 0, 0, 0), date_time_init(2004, 3, 31, 0, 0, 0).last_month
+  end
+
+  def test_last_year
+    assert_equal date_time_init(2004, 6, 5, 10, 0, 0), date_time_init(2005, 6, 5, 10, 0, 0).last_year
   end
 
   def test_days_to_week_start
-    assert_equal 0, date_time_init(2011,11,01,0,0,0).days_to_week_start(:tuesday)
-    assert_equal 1, date_time_init(2011,11,02,0,0,0).days_to_week_start(:tuesday)
-    assert_equal 2, date_time_init(2011,11,03,0,0,0).days_to_week_start(:tuesday)
-    assert_equal 3, date_time_init(2011,11,04,0,0,0).days_to_week_start(:tuesday)
-    assert_equal 4, date_time_init(2011,11,05,0,0,0).days_to_week_start(:tuesday)
-    assert_equal 5, date_time_init(2011,11,06,0,0,0).days_to_week_start(:tuesday)
-    assert_equal 6, date_time_init(2011,11,07,0,0,0).days_to_week_start(:tuesday)
-
-    assert_equal 3, date_time_init(2011,11,03,0,0,0).days_to_week_start(:monday)
-    assert_equal 3, date_time_init(2011,11,04,0,0,0).days_to_week_start(:tuesday)
-    assert_equal 3, date_time_init(2011,11,05,0,0,0).days_to_week_start(:wednesday)
-    assert_equal 3, date_time_init(2011,11,06,0,0,0).days_to_week_start(:thursday)
-    assert_equal 3, date_time_init(2011,11,07,0,0,0).days_to_week_start(:friday)
-    assert_equal 3, date_time_init(2011,11,8,0,0,0).days_to_week_start(:saturday)
-    assert_equal 3, date_time_init(2011,11,9,0,0,0).days_to_week_start(:sunday)
+    assert_equal 0, date_time_init(2011, 11, 01, 0, 0, 0).days_to_week_start(:tuesday)
+    assert_equal 1, date_time_init(2011, 11, 02, 0, 0, 0).days_to_week_start(:tuesday)
+    assert_equal 2, date_time_init(2011, 11, 03, 0, 0, 0).days_to_week_start(:tuesday)
+    assert_equal 3, date_time_init(2011, 11, 04, 0, 0, 0).days_to_week_start(:tuesday)
+    assert_equal 4, date_time_init(2011, 11, 05, 0, 0, 0).days_to_week_start(:tuesday)
+    assert_equal 5, date_time_init(2011, 11, 06, 0, 0, 0).days_to_week_start(:tuesday)
+    assert_equal 6, date_time_init(2011, 11, 07, 0, 0, 0).days_to_week_start(:tuesday)
+
+    assert_equal 3, date_time_init(2011, 11, 03, 0, 0, 0).days_to_week_start(:monday)
+    assert_equal 3, date_time_init(2011, 11, 04, 0, 0, 0).days_to_week_start(:tuesday)
+    assert_equal 3, date_time_init(2011, 11, 05, 0, 0, 0).days_to_week_start(:wednesday)
+    assert_equal 3, date_time_init(2011, 11, 06, 0, 0, 0).days_to_week_start(:thursday)
+    assert_equal 3, date_time_init(2011, 11, 07, 0, 0, 0).days_to_week_start(:friday)
+    assert_equal 3, date_time_init(2011, 11, 8, 0, 0, 0).days_to_week_start(:saturday)
+    assert_equal 3, date_time_init(2011, 11, 9, 0, 0, 0).days_to_week_start(:sunday)
   end
 
   def test_days_to_week_start_with_default_set
     with_bw_default(:friday) do
-      assert_equal 6, Time.local(2012,03,8,0,0,0).days_to_week_start
-      assert_equal 5, Time.local(2012,03,7,0,0,0).days_to_week_start
-      assert_equal 4, Time.local(2012,03,6,0,0,0).days_to_week_start
-      assert_equal 3, Time.local(2012,03,5,0,0,0).days_to_week_start
-      assert_equal 2, Time.local(2012,03,4,0,0,0).days_to_week_start
-      assert_equal 1, Time.local(2012,03,3,0,0,0).days_to_week_start
-      assert_equal 0, Time.local(2012,03,2,0,0,0).days_to_week_start
+      assert_equal 6, Time.local(2012, 03, 8, 0, 0, 0).days_to_week_start
+      assert_equal 5, Time.local(2012, 03, 7, 0, 0, 0).days_to_week_start
+      assert_equal 4, Time.local(2012, 03, 6, 0, 0, 0).days_to_week_start
+      assert_equal 3, Time.local(2012, 03, 5, 0, 0, 0).days_to_week_start
+      assert_equal 2, Time.local(2012, 03, 4, 0, 0, 0).days_to_week_start
+      assert_equal 1, Time.local(2012, 03, 3, 0, 0, 0).days_to_week_start
+      assert_equal 0, Time.local(2012, 03, 2, 0, 0, 0).days_to_week_start
     end
   end
 
   def test_beginning_of_week
-    assert_equal date_time_init(2005,1,31,0,0,0),  date_time_init(2005,2,4,10,10,10).beginning_of_week
-    assert_equal date_time_init(2005,11,28,0,0,0), date_time_init(2005,11,28,0,0,0).beginning_of_week #monday
-    assert_equal date_time_init(2005,11,28,0,0,0), date_time_init(2005,11,29,0,0,0).beginning_of_week #tuesday
-    assert_equal date_time_init(2005,11,28,0,0,0), date_time_init(2005,11,30,0,0,0).beginning_of_week #wednesday
-    assert_equal date_time_init(2005,11,28,0,0,0), date_time_init(2005,12,01,0,0,0).beginning_of_week #thursday
-    assert_equal date_time_init(2005,11,28,0,0,0), date_time_init(2005,12,02,0,0,0).beginning_of_week #friday
-    assert_equal date_time_init(2005,11,28,0,0,0), date_time_init(2005,12,03,0,0,0).beginning_of_week #saturday
-    assert_equal date_time_init(2005,11,28,0,0,0), date_time_init(2005,12,04,0,0,0).beginning_of_week #sunday
+    assert_equal date_time_init(2005, 1, 31, 0, 0, 0),  date_time_init(2005, 2, 4, 10, 10, 10).beginning_of_week
+    assert_equal date_time_init(2005, 11, 28, 0, 0, 0), date_time_init(2005, 11, 28, 0, 0, 0).beginning_of_week # monday
+    assert_equal date_time_init(2005, 11, 28, 0, 0, 0), date_time_init(2005, 11, 29, 0, 0, 0).beginning_of_week # tuesday
+    assert_equal date_time_init(2005, 11, 28, 0, 0, 0), date_time_init(2005, 11, 30, 0, 0, 0).beginning_of_week # wednesday
+    assert_equal date_time_init(2005, 11, 28, 0, 0, 0), date_time_init(2005, 12, 01, 0, 0, 0).beginning_of_week # thursday
+    assert_equal date_time_init(2005, 11, 28, 0, 0, 0), date_time_init(2005, 12, 02, 0, 0, 0).beginning_of_week # friday
+    assert_equal date_time_init(2005, 11, 28, 0, 0, 0), date_time_init(2005, 12, 03, 0, 0, 0).beginning_of_week # saturday
+    assert_equal date_time_init(2005, 11, 28, 0, 0, 0), date_time_init(2005, 12, 04, 0, 0, 0).beginning_of_week # sunday
   end
 
   def test_end_of_week
-    assert_equal date_time_init(2008,1,6,23,59,59,Rational(999999999, 1000)), date_time_init(2007,12,31,10,10,10).end_of_week
-    assert_equal date_time_init(2007,9,2,23,59,59,Rational(999999999, 1000)), date_time_init(2007,8,27,0,0,0).end_of_week #monday
-    assert_equal date_time_init(2007,9,2,23,59,59,Rational(999999999, 1000)), date_time_init(2007,8,28,0,0,0).end_of_week #tuesday
-    assert_equal date_time_init(2007,9,2,23,59,59,Rational(999999999, 1000)), date_time_init(2007,8,29,0,0,0).end_of_week #wednesday
-    assert_equal date_time_init(2007,9,2,23,59,59,Rational(999999999, 1000)), date_time_init(2007,8,30,0,0,0).end_of_week #thursday
-    assert_equal date_time_init(2007,9,2,23,59,59,Rational(999999999, 1000)), date_time_init(2007,8,31,0,0,0).end_of_week #friday
-    assert_equal date_time_init(2007,9,2,23,59,59,Rational(999999999, 1000)), date_time_init(2007,9,01,0,0,0).end_of_week #saturday
-    assert_equal date_time_init(2007,9,2,23,59,59,Rational(999999999, 1000)), date_time_init(2007,9,02,0,0,0).end_of_week #sunday
+    assert_equal date_time_init(2008, 1, 6, 23, 59, 59, Rational(999999999, 1000)), date_time_init(2007, 12, 31, 10, 10, 10).end_of_week
+    assert_equal date_time_init(2007, 9, 2, 23, 59, 59, Rational(999999999, 1000)), date_time_init(2007, 8, 27, 0, 0, 0).end_of_week # monday
+    assert_equal date_time_init(2007, 9, 2, 23, 59, 59, Rational(999999999, 1000)), date_time_init(2007, 8, 28, 0, 0, 0).end_of_week # tuesday
+    assert_equal date_time_init(2007, 9, 2, 23, 59, 59, Rational(999999999, 1000)), date_time_init(2007, 8, 29, 0, 0, 0).end_of_week # wednesday
+    assert_equal date_time_init(2007, 9, 2, 23, 59, 59, Rational(999999999, 1000)), date_time_init(2007, 8, 30, 0, 0, 0).end_of_week # thursday
+    assert_equal date_time_init(2007, 9, 2, 23, 59, 59, Rational(999999999, 1000)), date_time_init(2007, 8, 31, 0, 0, 0).end_of_week # friday
+    assert_equal date_time_init(2007, 9, 2, 23, 59, 59, Rational(999999999, 1000)), date_time_init(2007, 9, 01, 0, 0, 0).end_of_week # saturday
+    assert_equal date_time_init(2007, 9, 2, 23, 59, 59, Rational(999999999, 1000)), date_time_init(2007, 9, 02, 0, 0, 0).end_of_week # sunday
   end
 
   def test_end_of_month
-    assert_equal date_time_init(2005,3,31,23,59,59,Rational(999999999, 1000)), date_time_init(2005,3,20,10,10,10).end_of_month
-    assert_equal date_time_init(2005,2,28,23,59,59,Rational(999999999, 1000)), date_time_init(2005,2,20,10,10,10).end_of_month
-    assert_equal date_time_init(2005,4,30,23,59,59,Rational(999999999, 1000)), date_time_init(2005,4,20,10,10,10).end_of_month
+    assert_equal date_time_init(2005, 3, 31, 23, 59, 59, Rational(999999999, 1000)), date_time_init(2005, 3, 20, 10, 10, 10).end_of_month
+    assert_equal date_time_init(2005, 2, 28, 23, 59, 59, Rational(999999999, 1000)), date_time_init(2005, 2, 20, 10, 10, 10).end_of_month
+    assert_equal date_time_init(2005, 4, 30, 23, 59, 59, Rational(999999999, 1000)), date_time_init(2005, 4, 20, 10, 10, 10).end_of_month
   end
 
   def test_end_of_year
-    assert_equal date_time_init(2007,12,31,23,59,59,Rational(999999999, 1000)), date_time_init(2007,2,22,10,10,10).end_of_year
-    assert_equal date_time_init(2007,12,31,23,59,59,Rational(999999999, 1000)), date_time_init(2007,12,31,10,10,10).end_of_year
+    assert_equal date_time_init(2007, 12, 31, 23, 59, 59, Rational(999999999, 1000)), date_time_init(2007, 2, 22, 10, 10, 10).end_of_year
+    assert_equal date_time_init(2007, 12, 31, 23, 59, 59, Rational(999999999, 1000)), date_time_init(2007, 12, 31, 10, 10, 10).end_of_year
+  end
+
+  def test_next_occurring
+    assert_equal date_time_init(2017, 12, 18, 3, 14, 15), date_time_init(2017, 12, 14, 3, 14, 15).next_occurring(:monday)
+    assert_equal date_time_init(2017, 12, 19, 3, 14, 15), date_time_init(2017, 12, 14, 3, 14, 15).next_occurring(:tuesday)
+    assert_equal date_time_init(2017, 12, 20, 3, 14, 15), date_time_init(2017, 12, 14, 3, 14, 15).next_occurring(:wednesday)
+    assert_equal date_time_init(2017, 12, 21, 3, 14, 15), date_time_init(2017, 12, 14, 3, 14, 15).next_occurring(:thursday)
+    assert_equal date_time_init(2017, 12, 15, 3, 14, 15), date_time_init(2017, 12, 14, 3, 14, 15).next_occurring(:friday)
+    assert_equal date_time_init(2017, 12, 16, 3, 14, 15), date_time_init(2017, 12, 14, 3, 14, 15).next_occurring(:saturday)
+    assert_equal date_time_init(2017, 12, 17, 3, 14, 15), date_time_init(2017, 12, 14, 3, 14, 15).next_occurring(:sunday)
+  end
+
+  def test_prev_occurring
+    assert_equal date_time_init(2017, 12, 11, 3, 14, 15), date_time_init(2017, 12, 14, 3, 14, 15).prev_occurring(:monday)
+    assert_equal date_time_init(2017, 12, 12, 3, 14, 15), date_time_init(2017, 12, 14, 3, 14, 15).prev_occurring(:tuesday)
+    assert_equal date_time_init(2017, 12, 13, 3, 14, 15), date_time_init(2017, 12, 14, 3, 14, 15).prev_occurring(:wednesday)
+    assert_equal date_time_init(2017, 12,  7, 3, 14, 15), date_time_init(2017, 12, 14, 3, 14, 15).prev_occurring(:thursday)
+    assert_equal date_time_init(2017, 12,  8, 3, 14, 15), date_time_init(2017, 12, 14, 3, 14, 15).prev_occurring(:friday)
+    assert_equal date_time_init(2017, 12,  9, 3, 14, 15), date_time_init(2017, 12, 14, 3, 14, 15).prev_occurring(:saturday)
+    assert_equal date_time_init(2017, 12, 10, 3, 14, 15), date_time_init(2017, 12, 14, 3, 14, 15).prev_occurring(:sunday)
   end
 
   def test_monday_with_default_beginning_of_week_set
     with_bw_default(:saturday) do
-      assert_equal date_time_init(2012,9,17,0,0,0), date_time_init(2012,9,18,0,0,0).monday
+      assert_equal date_time_init(2012, 9, 17, 0, 0, 0), date_time_init(2012, 9, 18, 0, 0, 0).monday
     end
   end
 
   def test_sunday_with_default_beginning_of_week_set
     with_bw_default(:wednesday) do
-      assert_equal date_time_init(2012,9,23,23,59,59, Rational(999999999, 1000)), date_time_init(2012,9,19,0,0,0).sunday
+      assert_equal date_time_init(2012, 9, 23, 23, 59, 59, Rational(999999999, 1000)), date_time_init(2012, 9, 19, 0, 0, 0).sunday
     end
   end
 
   def test_on_weekend_on_saturday
-    assert date_time_init(2015,1,3,0,0,0).on_weekend?
-    assert date_time_init(2015,1,3,15,15,10).on_weekend?
+    assert date_time_init(2015, 1, 3, 0, 0, 0).on_weekend?
+    assert date_time_init(2015, 1, 3, 15, 15, 10).on_weekend?
   end
 
   def test_on_weekend_on_sunday
-    assert date_time_init(2015,1,4,0,0,0).on_weekend?
-    assert date_time_init(2015,1,4,15,15,10).on_weekend?
+    assert date_time_init(2015, 1, 4, 0, 0, 0).on_weekend?
+    assert date_time_init(2015, 1, 4, 15, 15, 10).on_weekend?
   end
 
   def test_on_weekend_on_monday
-    assert_not date_time_init(2015,1,5,0,0,0).on_weekend?
-    assert_not date_time_init(2015,1,5,15,15,10).on_weekend?
+    assert_not date_time_init(2015, 1, 5, 0, 0, 0).on_weekend?
+    assert_not date_time_init(2015, 1, 5, 15, 15, 10).on_weekend?
   end
 
   def test_on_weekday_on_sunday
-    assert_not date_time_init(2015,1,4,0,0,0).on_weekday?
-    assert_not date_time_init(2015,1,4,15,15,10).on_weekday?
+    assert_not date_time_init(2015, 1, 4, 0, 0, 0).on_weekday?
+    assert_not date_time_init(2015, 1, 4, 15, 15, 10).on_weekday?
   end
 
   def test_on_weekday_on_monday
-    assert date_time_init(2015,1,5,0,0,0).on_weekday?
-    assert date_time_init(2015,1,5,15,15,10).on_weekday?
+    assert date_time_init(2015, 1, 5, 0, 0, 0).on_weekday?
+    assert date_time_init(2015, 1, 5, 15, 15, 10).on_weekday?
   end
 
   def with_bw_default(bw = :monday)
diff --git a/activesupport/test/core_ext/date_and_time_compatibility_test.rb b/activesupport/test/core_ext/date_and_time_compatibility_test.rb
index 11cb1469da..266829a452 100644
--- a/activesupport/test/core_ext/date_and_time_compatibility_test.rb
+++ b/activesupport/test/core_ext/date_and_time_compatibility_test.rb
@@ -1,6 +1,8 @@
-require 'abstract_unit'
-require 'active_support/time'
-require 'time_zone_test_helpers'
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "active_support/time"
+require "time_zone_test_helpers"
 
 class DateAndTimeCompatibilityTest < ActiveSupport::TestCase
   include TimeZoneTestHelpers
@@ -10,37 +12,72 @@ class DateAndTimeCompatibilityTest < ActiveSupport::TestCase
     @date_time = DateTime.new(2016, 4, 23, 14, 11, 12, 0)
     @utc_offset = 3600
     @system_offset = -14400
-    @zone = ActiveSupport::TimeZone['London']
+    @zone = ActiveSupport::TimeZone["London"]
   end
 
   def test_time_to_time_preserves_timezone
     with_preserve_timezone(true) do
-      with_env_tz 'US/Eastern' do
-        time = Time.new(2016, 4, 23, 15, 11, 12, 3600).to_time
+      with_env_tz "US/Eastern" do
+        source = Time.new(2016, 4, 23, 15, 11, 12, 3600)
+        time = source.to_time
 
         assert_instance_of Time, time
         assert_equal @utc_time, time.getutc
         assert_equal @utc_offset, time.utc_offset
+        assert_equal source.object_id, time.object_id
       end
     end
   end
 
   def test_time_to_time_does_not_preserve_time_zone
     with_preserve_timezone(false) do
-      with_env_tz 'US/Eastern' do
-        time = Time.new(2016, 4, 23, 15, 11, 12, 3600).to_time
+      with_env_tz "US/Eastern" do
+        source = Time.new(2016, 4, 23, 15, 11, 12, 3600)
+        time = source.to_time
+
+        assert_instance_of Time, time
+        assert_equal @utc_time, time.getutc
+        assert_equal @system_offset, time.utc_offset
+        assert_not_equal source.object_id, time.object_id
+      end
+    end
+  end
+
+  def test_time_to_time_frozen_preserves_timezone
+    with_preserve_timezone(true) do
+      with_env_tz "US/Eastern" do
+        source = Time.new(2016, 4, 23, 15, 11, 12, 3600).freeze
+        time = source.to_time
+
+        assert_instance_of Time, time
+        assert_equal @utc_time, time.getutc
+        assert_equal @utc_offset, time.utc_offset
+        assert_equal source.object_id, time.object_id
+        assert_predicate time, :frozen?
+      end
+    end
+  end
+
+  def test_time_to_time_frozen_does_not_preserve_time_zone
+    with_preserve_timezone(false) do
+      with_env_tz "US/Eastern" do
+        source = Time.new(2016, 4, 23, 15, 11, 12, 3600).freeze
+        time = source.to_time
 
         assert_instance_of Time, time
         assert_equal @utc_time, time.getutc
         assert_equal @system_offset, time.utc_offset
+        assert_not_equal source.object_id, time.object_id
+        assert_not_predicate time, :frozen?
       end
     end
   end
 
   def test_datetime_to_time_preserves_timezone
     with_preserve_timezone(true) do
-      with_env_tz 'US/Eastern' do
-        time = DateTime.new(2016, 4, 23, 15, 11, 12, Rational(1,24)).to_time
+      with_env_tz "US/Eastern" do
+        source = DateTime.new(2016, 4, 23, 15, 11, 12, Rational(1, 24))
+        time = source.to_time
 
         assert_instance_of Time, time
         assert_equal @utc_time, time.getutc
@@ -51,27 +88,58 @@ class DateAndTimeCompatibilityTest < ActiveSupport::TestCase
 
   def test_datetime_to_time_does_not_preserve_time_zone
     with_preserve_timezone(false) do
-      with_env_tz 'US/Eastern' do
-        time = DateTime.new(2016, 4, 23, 15, 11, 12, Rational(1,24)).to_time
+      with_env_tz "US/Eastern" do
+        source = DateTime.new(2016, 4, 23, 15, 11, 12, Rational(1, 24))
+        time = source.to_time
+
+        assert_instance_of Time, time
+        assert_equal @utc_time, time.getutc
+        assert_equal @system_offset, time.utc_offset
+      end
+    end
+  end
+
+  def test_datetime_to_time_frozen_preserves_timezone
+    with_preserve_timezone(true) do
+      with_env_tz "US/Eastern" do
+        source = DateTime.new(2016, 4, 23, 15, 11, 12, Rational(1, 24)).freeze
+        time = source.to_time
+
+        assert_instance_of Time, time
+        assert_equal @utc_time, time.getutc
+        assert_equal @utc_offset, time.utc_offset
+        assert_not_predicate time, :frozen?
+      end
+    end
+  end
+
+  def test_datetime_to_time_frozen_does_not_preserve_time_zone
+    with_preserve_timezone(false) do
+      with_env_tz "US/Eastern" do
+        source = DateTime.new(2016, 4, 23, 15, 11, 12, Rational(1, 24)).freeze
+        time = source.to_time
 
         assert_instance_of Time, time
         assert_equal @utc_time, time.getutc
         assert_equal @system_offset, time.utc_offset
+        assert_not_predicate time, :frozen?
       end
     end
   end
 
   def test_twz_to_time_preserves_timezone
     with_preserve_timezone(true) do
-      with_env_tz 'US/Eastern' do
-        time = ActiveSupport::TimeWithZone.new(@utc_time, @zone).to_time
+      with_env_tz "US/Eastern" do
+        source = ActiveSupport::TimeWithZone.new(@utc_time, @zone)
+        time = source.to_time
 
         assert_instance_of Time, time
         assert_equal @utc_time, time.getutc
         assert_instance_of Time, time.getutc
         assert_equal @utc_offset, time.utc_offset
 
-        time = ActiveSupport::TimeWithZone.new(@date_time, @zone).to_time
+        source = ActiveSupport::TimeWithZone.new(@date_time, @zone)
+        time = source.to_time
 
         assert_instance_of Time, time
         assert_equal @date_time, time.getutc
@@ -83,15 +151,17 @@ class DateAndTimeCompatibilityTest < ActiveSupport::TestCase
 
   def test_twz_to_time_does_not_preserve_time_zone
     with_preserve_timezone(false) do
-      with_env_tz 'US/Eastern' do
-        time = ActiveSupport::TimeWithZone.new(@utc_time, @zone).to_time
+      with_env_tz "US/Eastern" do
+        source = ActiveSupport::TimeWithZone.new(@utc_time, @zone)
+        time = source.to_time
 
         assert_instance_of Time, time
         assert_equal @utc_time, time.getutc
         assert_instance_of Time, time.getutc
         assert_equal @system_offset, time.utc_offset
 
-        time = ActiveSupport::TimeWithZone.new(@date_time, @zone).to_time
+        source = ActiveSupport::TimeWithZone.new(@date_time, @zone)
+        time = source.to_time
 
         assert_instance_of Time, time
         assert_equal @date_time, time.getutc
@@ -101,10 +171,59 @@ class DateAndTimeCompatibilityTest < ActiveSupport::TestCase
     end
   end
 
+  def test_twz_to_time_frozen_preserves_timezone
+    with_preserve_timezone(true) do
+      with_env_tz "US/Eastern" do
+        source = ActiveSupport::TimeWithZone.new(@utc_time, @zone).freeze
+        time = source.to_time
+
+        assert_instance_of Time, time
+        assert_equal @utc_time, time.getutc
+        assert_instance_of Time, time.getutc
+        assert_equal @utc_offset, time.utc_offset
+        assert_not_predicate time, :frozen?
+
+        source = ActiveSupport::TimeWithZone.new(@date_time, @zone).freeze
+        time = source.to_time
+
+        assert_instance_of Time, time
+        assert_equal @date_time, time.getutc
+        assert_instance_of Time, time.getutc
+        assert_equal @utc_offset, time.utc_offset
+        assert_not_predicate time, :frozen?
+      end
+    end
+  end
+
+  def test_twz_to_time_frozen_does_not_preserve_time_zone
+    with_preserve_timezone(false) do
+      with_env_tz "US/Eastern" do
+        source = ActiveSupport::TimeWithZone.new(@utc_time, @zone).freeze
+        time = source.to_time
+
+        assert_instance_of Time, time
+        assert_equal @utc_time, time.getutc
+        assert_instance_of Time, time.getutc
+        assert_equal @system_offset, time.utc_offset
+        assert_not_predicate time, :frozen?
+
+        source = ActiveSupport::TimeWithZone.new(@date_time, @zone).freeze
+        time = source.to_time
+
+        assert_instance_of Time, time
+        assert_equal @date_time, time.getutc
+        assert_instance_of Time, time.getutc
+        assert_equal @system_offset, time.utc_offset
+        assert_not_predicate time, :frozen?
+      end
+    end
+  end
+
   def test_string_to_time_preserves_timezone
     with_preserve_timezone(true) do
-      with_env_tz 'US/Eastern' do
-        time = "2016-04-23T15:11:12+01:00".to_time
+      with_env_tz "US/Eastern" do
+        source = "2016-04-23T15:11:12+01:00"
+        time = source.to_time
 
         assert_instance_of Time, time
         assert_equal @utc_time, time.getutc
@@ -115,12 +234,41 @@ class DateAndTimeCompatibilityTest < ActiveSupport::TestCase
 
   def test_string_to_time_does_not_preserve_time_zone
     with_preserve_timezone(false) do
-      with_env_tz 'US/Eastern' do
-        time = "2016-04-23T15:11:12+01:00".to_time
+      with_env_tz "US/Eastern" do
+        source = "2016-04-23T15:11:12+01:00"
+        time = source.to_time
+
+        assert_instance_of Time, time
+        assert_equal @utc_time, time.getutc
+        assert_equal @system_offset, time.utc_offset
+      end
+    end
+  end
+
+  def test_string_to_time_frozen_preserves_timezone
+    with_preserve_timezone(true) do
+      with_env_tz "US/Eastern" do
+        source = "2016-04-23T15:11:12+01:00".freeze
+        time = source.to_time
+
+        assert_instance_of Time, time
+        assert_equal @utc_time, time.getutc
+        assert_equal @utc_offset, time.utc_offset
+        assert_not_predicate time, :frozen?
+      end
+    end
+  end
+
+  def test_string_to_time_frozen_does_not_preserve_time_zone
+    with_preserve_timezone(false) do
+      with_env_tz "US/Eastern" do
+        source = "2016-04-23T15:11:12+01:00".freeze
+        time = source.to_time
 
         assert_instance_of Time, time
         assert_equal @utc_time, time.getutc
         assert_equal @system_offset, time.utc_offset
+        assert_not_predicate time, :frozen?
       end
     end
   end
diff --git a/activesupport/test/core_ext/date_ext_test.rb b/activesupport/test/core_ext/date_ext_test.rb
index a7219eee31..23d17956df 100644
--- a/activesupport/test/core_ext/date_ext_test.rb
+++ b/activesupport/test/core_ext/date_ext_test.rb
@@ -1,22 +1,24 @@
-require 'abstract_unit'
-require 'active_support/time'
-require 'core_ext/date_and_time_behavior'
-require 'time_zone_test_helpers'
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "active_support/time"
+require "core_ext/date_and_time_behavior"
+require "time_zone_test_helpers"
 
 class DateExtCalculationsTest < ActiveSupport::TestCase
-  def date_time_init(year,month,day,*args)
-    Date.new(year,month,day)
+  def date_time_init(year, month, day, *args)
+    Date.new(year, month, day)
   end
 
   include DateAndTimeBehavior
   include TimeZoneTestHelpers
 
   def test_yesterday_in_calendar_reform
-    assert_equal Date.new(1582,10,4), Date.new(1582,10,15).yesterday
+    assert_equal Date.new(1582, 10, 4), Date.new(1582, 10, 15).yesterday
   end
 
   def test_tomorrow_in_calendar_reform
-    assert_equal Date.new(1582,10,15), Date.new(1582,10,4).tomorrow
+    assert_equal Date.new(1582, 10, 15), Date.new(1582, 10, 4).tomorrow
   end
 
   def test_to_s
@@ -47,7 +49,7 @@ class DateExtCalculationsTest < ActiveSupport::TestCase
   end
 
   def test_to_time
-    with_env_tz 'US/Eastern' do
+    with_env_tz "US/Eastern" do
       assert_equal Time, Date.new(2005, 2, 21).to_time.class
       assert_equal Time.local(2005, 2, 21), Date.new(2005, 2, 21).to_time
       assert_equal Time.local(2005, 2, 21).utc_offset, Date.new(2005, 2, 21).to_time.utc_offset
@@ -81,110 +83,102 @@ class DateExtCalculationsTest < ActiveSupport::TestCase
   end
 
   def test_change
-    assert_equal Date.new(2005, 2, 21), Date.new(2005, 2, 11).change(:day => 21)
-    assert_equal Date.new(2007, 5, 11), Date.new(2005, 2, 11).change(:year => 2007, :month => 5)
-    assert_equal Date.new(2006,2,22), Date.new(2005,2,22).change(:year => 2006)
-    assert_equal Date.new(2005,6,22), Date.new(2005,2,22).change(:month => 6)
+    assert_equal Date.new(2005, 2, 21), Date.new(2005, 2, 11).change(day: 21)
+    assert_equal Date.new(2007, 5, 11), Date.new(2005, 2, 11).change(year: 2007, month: 5)
+    assert_equal Date.new(2006, 2, 22), Date.new(2005, 2, 22).change(year: 2006)
+    assert_equal Date.new(2005, 6, 22), Date.new(2005, 2, 22).change(month: 6)
   end
 
   def test_sunday
-    assert_equal Date.new(2008,3,2), Date.new(2008,3,02).sunday
-    assert_equal Date.new(2008,3,2), Date.new(2008,2,29).sunday
+    assert_equal Date.new(2008, 3, 2), Date.new(2008, 3, 02).sunday
+    assert_equal Date.new(2008, 3, 2), Date.new(2008, 2, 29).sunday
   end
 
   def test_beginning_of_week_in_calendar_reform
-    assert_equal Date.new(1582,10,1), Date.new(1582,10,15).beginning_of_week #friday
+    assert_equal Date.new(1582, 10, 1), Date.new(1582, 10, 15).beginning_of_week # friday
   end
 
   def test_end_of_week_in_calendar_reform
-    assert_equal Date.new(1582,10,17), Date.new(1582,10,4).end_of_week #thursday
+    assert_equal Date.new(1582, 10, 17), Date.new(1582, 10, 4).end_of_week # thursday
   end
 
   def test_end_of_year
-    assert_equal Date.new(2008,12,31).to_s, Date.new(2008,2,22).end_of_year.to_s
+    assert_equal Date.new(2008, 12, 31).to_s, Date.new(2008, 2, 22).end_of_year.to_s
   end
 
   def test_end_of_month
-    assert_equal Date.new(2005,3,31), Date.new(2005,3,20).end_of_month
-    assert_equal Date.new(2005,2,28), Date.new(2005,2,20).end_of_month
-    assert_equal Date.new(2005,4,30), Date.new(2005,4,20).end_of_month
+    assert_equal Date.new(2005, 3, 31), Date.new(2005, 3, 20).end_of_month
+    assert_equal Date.new(2005, 2, 28), Date.new(2005, 2, 20).end_of_month
+    assert_equal Date.new(2005, 4, 30), Date.new(2005, 4, 20).end_of_month
   end
 
   def test_prev_year_in_leap_years
-    assert_equal Date.new(1999,2,28), Date.new(2000,2,29).prev_year
+    assert_equal Date.new(1999, 2, 28), Date.new(2000, 2, 29).prev_year
   end
 
   def test_prev_year_in_calendar_reform
-    assert_equal Date.new(1582,10,4), Date.new(1583,10,14).prev_year
-  end
-
-  def test_last_year
-    assert_equal Date.new(2004,6,5),  Date.new(2005,6,5).last_year
+    assert_equal Date.new(1582, 10, 4), Date.new(1583, 10, 14).prev_year
   end
 
   def test_last_year_in_leap_years
-    assert_equal Date.new(1999,2,28), Date.new(2000,2,29).last_year
+    assert_equal Date.new(1999, 2, 28), Date.new(2000, 2, 29).last_year
   end
 
   def test_last_year_in_calendar_reform
-    assert_equal Date.new(1582,10,4), Date.new(1583,10,14).last_year
+    assert_equal Date.new(1582, 10, 4), Date.new(1583, 10, 14).last_year
   end
 
   def test_next_year_in_leap_years
-    assert_equal Date.new(2001,2,28), Date.new(2000,2,29).next_year
+    assert_equal Date.new(2001, 2, 28), Date.new(2000, 2, 29).next_year
   end
 
   def test_next_year_in_calendar_reform
-    assert_equal Date.new(1582,10,4), Date.new(1581,10,10).next_year
+    assert_equal Date.new(1582, 10, 4), Date.new(1581, 10, 10).next_year
   end
 
   def test_advance
-    assert_equal Date.new(2006,2,28), Date.new(2005,2,28).advance(:years => 1)
-    assert_equal Date.new(2005,6,28), Date.new(2005,2,28).advance(:months => 4)
-    assert_equal Date.new(2005,3,21), Date.new(2005,2,28).advance(:weeks => 3)
-    assert_equal Date.new(2005,3,5), Date.new(2005,2,28).advance(:days => 5)
-    assert_equal Date.new(2012,9,28), Date.new(2005,2,28).advance(:years => 7, :months => 7)
-    assert_equal Date.new(2013,10,3), Date.new(2005,2,28).advance(:years => 7, :months => 19, :days => 5)
-    assert_equal Date.new(2013,10,17), Date.new(2005,2,28).advance(:years => 7, :months => 19, :weeks => 2, :days => 5)
-    assert_equal Date.new(2005,2,28), Date.new(2004,2,29).advance(:years => 1) #leap day plus one year
+    assert_equal Date.new(2006, 2, 28), Date.new(2005, 2, 28).advance(years: 1)
+    assert_equal Date.new(2005, 6, 28), Date.new(2005, 2, 28).advance(months: 4)
+    assert_equal Date.new(2005, 3, 21), Date.new(2005, 2, 28).advance(weeks: 3)
+    assert_equal Date.new(2005, 3, 5), Date.new(2005, 2, 28).advance(days: 5)
+    assert_equal Date.new(2012, 9, 28), Date.new(2005, 2, 28).advance(years: 7, months: 7)
+    assert_equal Date.new(2013, 10, 3), Date.new(2005, 2, 28).advance(years: 7, months: 19, days: 5)
+    assert_equal Date.new(2013, 10, 17), Date.new(2005, 2, 28).advance(years: 7, months: 19, weeks: 2, days: 5)
+    assert_equal Date.new(2005, 2, 28), Date.new(2004, 2, 29).advance(years: 1) # leap day plus one year
   end
 
   def test_advance_does_first_years_and_then_days
-    assert_equal Date.new(2012, 2, 29), Date.new(2011, 2, 28).advance(:years => 1, :days => 1)
+    assert_equal Date.new(2012, 2, 29), Date.new(2011, 2, 28).advance(years: 1, days: 1)
     # If day was done first we would jump to 2012-03-01 instead.
   end
 
   def test_advance_does_first_months_and_then_days
-    assert_equal Date.new(2010, 3, 29), Date.new(2010, 2, 28).advance(:months => 1, :days => 1)
+    assert_equal Date.new(2010, 3, 29), Date.new(2010, 2, 28).advance(months: 1, days: 1)
     # If day was done first we would jump to 2010-04-01 instead.
   end
 
   def test_advance_in_calendar_reform
-    assert_equal Date.new(1582,10,15), Date.new(1582,10,4).advance(:days => 1)
-    assert_equal Date.new(1582,10,4), Date.new(1582,10,15).advance(:days => -1)
+    assert_equal Date.new(1582, 10, 15), Date.new(1582, 10, 4).advance(days: 1)
+    assert_equal Date.new(1582, 10, 4), Date.new(1582, 10, 15).advance(days: -1)
     5.upto(14) do |day|
-      assert_equal Date.new(1582,10,4), Date.new(1582,9,day).advance(:months => 1)
-      assert_equal Date.new(1582,10,4), Date.new(1582,11,day).advance(:months => -1)
-      assert_equal Date.new(1582,10,4), Date.new(1581,10,day).advance(:years => 1)
-      assert_equal Date.new(1582,10,4), Date.new(1583,10,day).advance(:years => -1)
+      assert_equal Date.new(1582, 10, 4), Date.new(1582, 9, day).advance(months: 1)
+      assert_equal Date.new(1582, 10, 4), Date.new(1582, 11, day).advance(months: -1)
+      assert_equal Date.new(1582, 10, 4), Date.new(1581, 10, day).advance(years: 1)
+      assert_equal Date.new(1582, 10, 4), Date.new(1583, 10, day).advance(years: -1)
     end
   end
 
   def test_last_week
-    assert_equal Date.new(2005,5,9), Date.new(2005,5,17).last_week
-    assert_equal Date.new(2006,12,25), Date.new(2007,1,7).last_week
-    assert_equal Date.new(2010,2,12), Date.new(2010,2,19).last_week(:friday)
-    assert_equal Date.new(2010,2,13), Date.new(2010,2,19).last_week(:saturday)
-    assert_equal Date.new(2010,2,27), Date.new(2010,3,4).last_week(:saturday)
+    assert_equal Date.new(2005, 5, 9), Date.new(2005, 5, 17).last_week
+    assert_equal Date.new(2006, 12, 25), Date.new(2007, 1, 7).last_week
+    assert_equal Date.new(2010, 2, 12), Date.new(2010, 2, 19).last_week(:friday)
+    assert_equal Date.new(2010, 2, 13), Date.new(2010, 2, 19).last_week(:saturday)
+    assert_equal Date.new(2010, 2, 27), Date.new(2010, 3, 4).last_week(:saturday)
   end
 
   def test_next_week_in_calendar_reform
-    assert_equal Date.new(1582,10,15), Date.new(1582,9,30).next_week(:friday)
-    assert_equal Date.new(1582,10,18), Date.new(1582,10,4).next_week
-  end
-
-  def test_last_month_on_31st
-    assert_equal Date.new(2004, 2, 29), Date.new(2004, 3, 31).last_month
+    assert_equal Date.new(1582, 10, 15), Date.new(1582, 9, 30).next_week(:friday)
+    assert_equal Date.new(1582, 10, 18), Date.new(1582, 10, 4).next_week
   end
 
   def test_last_quarter_on_31st
@@ -196,7 +190,7 @@ class DateExtCalculationsTest < ActiveSupport::TestCase
   end
 
   def test_yesterday_constructor_when_zone_is_not_set
-    with_env_tz 'UTC' do
+    with_env_tz "UTC" do
       with_tz_default do
         assert_equal(Date.today - 1, Date.yesterday)
       end
@@ -204,8 +198,8 @@ class DateExtCalculationsTest < ActiveSupport::TestCase
   end
 
   def test_yesterday_constructor_when_zone_is_set
-    with_env_tz 'UTC' do
-      with_tz_default ActiveSupport::TimeZone['Eastern Time (US & Canada)'] do # UTC -5
+    with_env_tz "UTC" do
+      with_tz_default ActiveSupport::TimeZone["Eastern Time (US & Canada)"] do # UTC -5
         Time.stub(:now, Time.local(2000, 1, 1)) do
           assert_equal Date.new(1999, 12, 30), Date.yesterday
         end
@@ -218,7 +212,7 @@ class DateExtCalculationsTest < ActiveSupport::TestCase
   end
 
   def test_tomorrow_constructor_when_zone_is_not_set
-    with_env_tz 'UTC' do
+    with_env_tz "UTC" do
       with_tz_default do
         assert_equal(Date.today + 1, Date.tomorrow)
       end
@@ -226,8 +220,8 @@ class DateExtCalculationsTest < ActiveSupport::TestCase
   end
 
   def test_tomorrow_constructor_when_zone_is_set
-    with_env_tz 'UTC' do
-      with_tz_default ActiveSupport::TimeZone['Europe/Paris'] do # UTC +1
+    with_env_tz "UTC" do
+      with_tz_default ActiveSupport::TimeZone["Europe/Paris"] do # UTC +1
         Time.stub(:now, Time.local(1999, 12, 31, 23)) do
           assert_equal Date.new(2000, 1, 2), Date.tomorrow
         end
@@ -236,101 +230,101 @@ class DateExtCalculationsTest < ActiveSupport::TestCase
   end
 
   def test_since
-    assert_equal Time.local(2005,2,21,0,0,45), Date.new(2005,2,21).since(45)
+    assert_equal Time.local(2005, 2, 21, 0, 0, 45), Date.new(2005, 2, 21).since(45)
   end
 
   def test_since_when_zone_is_set
-    zone = ActiveSupport::TimeZone['Eastern Time (US & Canada)']
-    with_env_tz 'UTC' do
+    zone = ActiveSupport::TimeZone["Eastern Time (US & Canada)"]
+    with_env_tz "UTC" do
       with_tz_default zone do
-        assert_equal zone.local(2005,2,21,0,0,45), Date.new(2005,2,21).since(45)
-        assert_equal zone, Date.new(2005,2,21).since(45).time_zone
+        assert_equal zone.local(2005, 2, 21, 0, 0, 45), Date.new(2005, 2, 21).since(45)
+        assert_equal zone, Date.new(2005, 2, 21).since(45).time_zone
       end
     end
   end
 
   def test_ago
-    assert_equal Time.local(2005,2,20,23,59,15), Date.new(2005,2,21).ago(45)
+    assert_equal Time.local(2005, 2, 20, 23, 59, 15), Date.new(2005, 2, 21).ago(45)
   end
 
   def test_ago_when_zone_is_set
-    zone = ActiveSupport::TimeZone['Eastern Time (US & Canada)']
-    with_env_tz 'UTC' do
+    zone = ActiveSupport::TimeZone["Eastern Time (US & Canada)"]
+    with_env_tz "UTC" do
       with_tz_default zone do
-        assert_equal zone.local(2005,2,20,23,59,15), Date.new(2005,2,21).ago(45)
-        assert_equal zone, Date.new(2005,2,21).ago(45).time_zone
+        assert_equal zone.local(2005, 2, 20, 23, 59, 15), Date.new(2005, 2, 21).ago(45)
+        assert_equal zone, Date.new(2005, 2, 21).ago(45).time_zone
       end
     end
   end
 
   def test_beginning_of_day
-    assert_equal Time.local(2005,2,21,0,0,0), Date.new(2005,2,21).beginning_of_day
+    assert_equal Time.local(2005, 2, 21, 0, 0, 0), Date.new(2005, 2, 21).beginning_of_day
   end
 
   def test_middle_of_day
-    assert_equal Time.local(2005,2,21,12,0,0), Date.new(2005,2,21).middle_of_day
+    assert_equal Time.local(2005, 2, 21, 12, 0, 0), Date.new(2005, 2, 21).middle_of_day
   end
 
   def test_beginning_of_day_when_zone_is_set
-    zone = ActiveSupport::TimeZone['Eastern Time (US & Canada)']
-    with_env_tz 'UTC' do
+    zone = ActiveSupport::TimeZone["Eastern Time (US & Canada)"]
+    with_env_tz "UTC" do
       with_tz_default zone do
-        assert_equal zone.local(2005,2,21,0,0,0), Date.new(2005,2,21).beginning_of_day
-        assert_equal zone, Date.new(2005,2,21).beginning_of_day.time_zone
+        assert_equal zone.local(2005, 2, 21, 0, 0, 0), Date.new(2005, 2, 21).beginning_of_day
+        assert_equal zone, Date.new(2005, 2, 21).beginning_of_day.time_zone
       end
     end
   end
 
   def test_end_of_day
-    assert_equal Time.local(2005,2,21,23,59,59,Rational(999999999, 1000)), Date.new(2005,2,21).end_of_day
+    assert_equal Time.local(2005, 2, 21, 23, 59, 59, Rational(999999999, 1000)), Date.new(2005, 2, 21).end_of_day
   end
 
   def test_end_of_day_when_zone_is_set
-    zone = ActiveSupport::TimeZone['Eastern Time (US & Canada)']
-    with_env_tz 'UTC' do
+    zone = ActiveSupport::TimeZone["Eastern Time (US & Canada)"]
+    with_env_tz "UTC" do
       with_tz_default zone do
-        assert_equal zone.local(2005,2,21,23,59,59,Rational(999999999, 1000)), Date.new(2005,2,21).end_of_day
-        assert_equal zone, Date.new(2005,2,21).end_of_day.time_zone
+        assert_equal zone.local(2005, 2, 21, 23, 59, 59, Rational(999999999, 1000)), Date.new(2005, 2, 21).end_of_day
+        assert_equal zone, Date.new(2005, 2, 21).end_of_day.time_zone
       end
     end
   end
 
   def test_all_day
-    beginning_of_day = Time.local(2011,6,7,0,0,0)
-    end_of_day = Time.local(2011,6,7,23,59,59,Rational(999999999, 1000))
-    assert_equal beginning_of_day..end_of_day, Date.new(2011,6,7).all_day
+    beginning_of_day = Time.local(2011, 6, 7, 0, 0, 0)
+    end_of_day = Time.local(2011, 6, 7, 23, 59, 59, Rational(999999999, 1000))
+    assert_equal beginning_of_day..end_of_day, Date.new(2011, 6, 7).all_day
   end
 
   def test_all_day_when_zone_is_set
     zone = ActiveSupport::TimeZone["Hawaii"]
     with_env_tz "UTC" do
       with_tz_default zone do
-        beginning_of_day = zone.local(2011,6,7,0,0,0)
-        end_of_day = zone.local(2011,6,7,23,59,59,Rational(999999999, 1000))
-        assert_equal beginning_of_day..end_of_day, Date.new(2011,6,7).all_day
+        beginning_of_day = zone.local(2011, 6, 7, 0, 0, 0)
+        end_of_day = zone.local(2011, 6, 7, 23, 59, 59, Rational(999999999, 1000))
+        assert_equal beginning_of_day..end_of_day, Date.new(2011, 6, 7).all_day
       end
     end
   end
 
   def test_all_week
-    assert_equal Date.new(2011,6,6)..Date.new(2011,6,12), Date.new(2011,6,7).all_week
-    assert_equal Date.new(2011,6,5)..Date.new(2011,6,11), Date.new(2011,6,7).all_week(:sunday)
+    assert_equal Date.new(2011, 6, 6)..Date.new(2011, 6, 12), Date.new(2011, 6, 7).all_week
+    assert_equal Date.new(2011, 6, 5)..Date.new(2011, 6, 11), Date.new(2011, 6, 7).all_week(:sunday)
   end
 
   def test_all_month
-    assert_equal Date.new(2011,6,1)..Date.new(2011,6,30), Date.new(2011,6,7).all_month
+    assert_equal Date.new(2011, 6, 1)..Date.new(2011, 6, 30), Date.new(2011, 6, 7).all_month
   end
 
   def test_all_quarter
-    assert_equal Date.new(2011,4,1)..Date.new(2011,6,30), Date.new(2011,6,7).all_quarter
+    assert_equal Date.new(2011, 4, 1)..Date.new(2011, 6, 30), Date.new(2011, 6, 7).all_quarter
   end
 
   def test_all_year
-    assert_equal Date.new(2011,1,1)..Date.new(2011,12,31), Date.new(2011,6,7).all_year
+    assert_equal Date.new(2011, 1, 1)..Date.new(2011, 12, 31), Date.new(2011, 6, 7).all_year
   end
 
   def test_xmlschema
-    with_env_tz 'US/Eastern' do
+    with_env_tz "US/Eastern" do
       assert_match(/^1980-02-28T00:00:00-05:?00$/, Date.new(1980, 2, 28).xmlschema)
       assert_match(/^1980-06-28T00:00:00-04:?00$/, Date.new(1980, 6, 28).xmlschema)
       # these tests are only of interest on platforms where older dates #to_time fail over to DateTime
@@ -342,8 +336,8 @@ class DateExtCalculationsTest < ActiveSupport::TestCase
   end
 
   def test_xmlschema_when_zone_is_set
-    with_env_tz 'UTC' do
-      with_tz_default ActiveSupport::TimeZone['Eastern Time (US & Canada)'] do # UTC -5
+    with_env_tz "UTC" do
+      with_tz_default ActiveSupport::TimeZone["Eastern Time (US & Canada)"] do # UTC -5
         assert_match(/^1980-02-28T00:00:00-05:?00$/, Date.new(1980, 2, 28).xmlschema)
         assert_match(/^1980-06-28T00:00:00-04:?00$/, Date.new(1980, 6, 28).xmlschema)
       end
@@ -353,21 +347,21 @@ class DateExtCalculationsTest < ActiveSupport::TestCase
   def test_past
     Date.stub(:current, Date.new(2000, 1, 1)) do
       assert_equal true, Date.new(1999, 12, 31).past?
-      assert_equal false, Date.new(2000,1,1).past?
-      assert_equal false, Date.new(2000,1,2).past?
+      assert_equal false, Date.new(2000, 1, 1).past?
+      assert_equal false, Date.new(2000, 1, 2).past?
     end
   end
 
   def test_future
     Date.stub(:current, Date.new(2000, 1, 1)) do
       assert_equal false, Date.new(1999, 12, 31).future?
-      assert_equal false, Date.new(2000,1,1).future?
-      assert_equal true, Date.new(2000,1,2).future?
+      assert_equal false, Date.new(2000, 1, 1).future?
+      assert_equal true, Date.new(2000, 1, 2).future?
     end
   end
 
   def test_current_returns_date_today_when_zone_not_set
-    with_env_tz 'US/Central' do
+    with_env_tz "US/Central" do
       Time.stub(:now, Time.local(1999, 12, 31, 23)) do
         assert_equal Date.today, Date.current
       end
@@ -375,8 +369,8 @@ class DateExtCalculationsTest < ActiveSupport::TestCase
   end
 
   def test_current_returns_time_zone_today_when_zone_is_set
-    Time.zone = ActiveSupport::TimeZone['Eastern Time (US & Canada)']
-    with_env_tz 'US/Central' do
+    Time.zone = ActiveSupport::TimeZone["Eastern Time (US & Canada)"]
+    with_env_tz "US/Central" do
       assert_equal ::Time.zone.today, Date.current
     end
   ensure
@@ -384,9 +378,9 @@ class DateExtCalculationsTest < ActiveSupport::TestCase
   end
 
   def test_date_advance_should_not_change_passed_options_hash
-    options = { :years => 3, :months => 11, :days => 2 }
-    Date.new(2005,2,28).advance(options)
-    assert_equal({ :years => 3, :months => 11, :days => 2 }, options)
+    options = { years: 3, months: 11, days: 2 }
+    Date.new(2005, 2, 28).advance(options)
+    assert_equal({ years: 3, months: 11, days: 2 }, options)
   end
 end
 
@@ -395,6 +389,10 @@ class DateExtBehaviorTest < ActiveSupport::TestCase
     assert Date.new.acts_like_date?
   end
 
+  def test_blank?
+    assert_not Date.new.blank?
+  end
+
   def test_freeze_doesnt_clobber_memoized_instance_methods
     assert_nothing_raised do
       Date.today.freeze.inspect
@@ -407,4 +405,3 @@ class DateExtBehaviorTest < ActiveSupport::TestCase
     end
   end
 end
-
diff --git a/activesupport/test/core_ext/date_time_ext_test.rb b/activesupport/test/core_ext/date_time_ext_test.rb
index 306316efcd..f4c9dfcb25 100644
--- a/activesupport/test/core_ext/date_time_ext_test.rb
+++ b/activesupport/test/core_ext/date_time_ext_test.rb
@@ -1,11 +1,13 @@
-require 'abstract_unit'
-require 'active_support/time'
-require 'core_ext/date_and_time_behavior'
-require 'time_zone_test_helpers'
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "active_support/time"
+require "core_ext/date_and_time_behavior"
+require "time_zone_test_helpers"
 
 class DateTimeExtCalculationsTest < ActiveSupport::TestCase
-  def date_time_init(year,month,day,hour,minute,second,*args)
-    DateTime.civil(year,month,day,hour,minute,second)
+  def date_time_init(year, month, day, hour, minute, second, usec = 0)
+    DateTime.civil(year, month, day, hour, minute, second + (usec / 1000000))
   end
 
   include DateAndTimeBehavior
@@ -35,26 +37,26 @@ class DateTimeExtCalculationsTest < ActiveSupport::TestCase
   end
 
   def test_custom_date_format
-    Time::DATE_FORMATS[:custom] = '%Y%m%d%H%M%S'
-    assert_equal '20050221143000', DateTime.new(2005, 2, 21, 14, 30, 0).to_s(:custom)
+    Time::DATE_FORMATS[:custom] = "%Y%m%d%H%M%S"
+    assert_equal "20050221143000", DateTime.new(2005, 2, 21, 14, 30, 0).to_s(:custom)
     Time::DATE_FORMATS.delete(:custom)
   end
 
   def test_localtime
-    with_env_tz 'US/Eastern' do
+    with_env_tz "US/Eastern" do
       assert_instance_of Time, DateTime.new(2016, 3, 11, 15, 11, 12, 0).localtime
       assert_equal Time.local(2016, 3, 11, 10, 11, 12), DateTime.new(2016, 3, 11, 15, 11, 12, 0).localtime
       assert_equal Time.local(2016, 3, 21, 11, 11, 12), DateTime.new(2016, 3, 21, 15, 11, 12, 0).localtime
-      assert_equal Time.local(2016, 4, 1, 11, 11, 12), DateTime.new(2016, 4, 1, 16, 11, 12, Rational(1,24)).localtime
+      assert_equal Time.local(2016, 4, 1, 11, 11, 12), DateTime.new(2016, 4, 1, 16, 11, 12, Rational(1, 24)).localtime
     end
   end
 
   def test_getlocal
-    with_env_tz 'US/Eastern' do
+    with_env_tz "US/Eastern" do
       assert_instance_of Time, DateTime.new(2016, 3, 11, 15, 11, 12, 0).getlocal
       assert_equal Time.local(2016, 3, 11, 10, 11, 12), DateTime.new(2016, 3, 11, 15, 11, 12, 0).getlocal
       assert_equal Time.local(2016, 3, 21, 11, 11, 12), DateTime.new(2016, 3, 21, 15, 11, 12, 0).getlocal
-      assert_equal Time.local(2016, 4, 1, 11, 11, 12), DateTime.new(2016, 4, 1, 16, 11, 12, Rational(1,24)).getlocal
+      assert_equal Time.local(2016, 4, 1, 11, 11, 12), DateTime.new(2016, 4, 1, 16, 11, 12, Rational(1, 24)).getlocal
     end
   end
 
@@ -67,7 +69,7 @@ class DateTimeExtCalculationsTest < ActiveSupport::TestCase
   end
 
   def test_to_time
-    with_env_tz 'US/Eastern' do
+    with_env_tz "US/Eastern" do
       assert_instance_of Time, DateTime.new(2005, 2, 21, 10, 11, 12, 0).to_time
 
       if ActiveSupport.to_time_preserves_timezone
@@ -90,134 +92,136 @@ class DateTimeExtCalculationsTest < ActiveSupport::TestCase
   end
 
   def test_seconds_since_midnight
-    assert_equal 1,DateTime.civil(2005,1,1,0,0,1).seconds_since_midnight
-    assert_equal 60,DateTime.civil(2005,1,1,0,1,0).seconds_since_midnight
-    assert_equal 3660,DateTime.civil(2005,1,1,1,1,0).seconds_since_midnight
-    assert_equal 86399,DateTime.civil(2005,1,1,23,59,59).seconds_since_midnight
+    assert_equal 1, DateTime.civil(2005, 1, 1, 0, 0, 1).seconds_since_midnight
+    assert_equal 60, DateTime.civil(2005, 1, 1, 0, 1, 0).seconds_since_midnight
+    assert_equal 3660, DateTime.civil(2005, 1, 1, 1, 1, 0).seconds_since_midnight
+    assert_equal 86399, DateTime.civil(2005, 1, 1, 23, 59, 59).seconds_since_midnight
   end
 
   def test_seconds_until_end_of_day
-    assert_equal 0, DateTime.civil(2005,1,1,23,59,59).seconds_until_end_of_day
-    assert_equal 1, DateTime.civil(2005,1,1,23,59,58).seconds_until_end_of_day
-    assert_equal 60, DateTime.civil(2005,1,1,23,58,59).seconds_until_end_of_day
-    assert_equal 3660, DateTime.civil(2005,1,1,22,58,59).seconds_until_end_of_day
-    assert_equal 86399, DateTime.civil(2005,1,1,0,0,0).seconds_until_end_of_day
+    assert_equal 0, DateTime.civil(2005, 1, 1, 23, 59, 59).seconds_until_end_of_day
+    assert_equal 1, DateTime.civil(2005, 1, 1, 23, 59, 58).seconds_until_end_of_day
+    assert_equal 60, DateTime.civil(2005, 1, 1, 23, 58, 59).seconds_until_end_of_day
+    assert_equal 3660, DateTime.civil(2005, 1, 1, 22, 58, 59).seconds_until_end_of_day
+    assert_equal 86399, DateTime.civil(2005, 1, 1, 0, 0, 0).seconds_until_end_of_day
   end
 
   def test_beginning_of_day
-    assert_equal DateTime.civil(2005,2,4,0,0,0), DateTime.civil(2005,2,4,10,10,10).beginning_of_day
+    assert_equal DateTime.civil(2005, 2, 4, 0, 0, 0), DateTime.civil(2005, 2, 4, 10, 10, 10).beginning_of_day
   end
 
   def test_middle_of_day
-    assert_equal DateTime.civil(2005,2,4,12,0,0), DateTime.civil(2005,2,4,10,10,10).middle_of_day
+    assert_equal DateTime.civil(2005, 2, 4, 12, 0, 0), DateTime.civil(2005, 2, 4, 10, 10, 10).middle_of_day
   end
 
   def test_end_of_day
-    assert_equal DateTime.civil(2005,2,4,23,59,59), DateTime.civil(2005,2,4,10,10,10).end_of_day
+    assert_equal DateTime.civil(2005, 2, 4, 23, 59, Rational(59999999999, 1000000000)), DateTime.civil(2005, 2, 4, 10, 10, 10).end_of_day
   end
 
   def test_beginning_of_hour
-    assert_equal DateTime.civil(2005,2,4,19,0,0), DateTime.civil(2005,2,4,19,30,10).beginning_of_hour
+    assert_equal DateTime.civil(2005, 2, 4, 19, 0, 0), DateTime.civil(2005, 2, 4, 19, 30, 10).beginning_of_hour
   end
 
   def test_end_of_hour
-    assert_equal DateTime.civil(2005,2,4,19,59,59), DateTime.civil(2005,2,4,19,30,10).end_of_hour
+    assert_equal DateTime.civil(2005, 2, 4, 19, 59, Rational(59999999999, 1000000000)), DateTime.civil(2005, 2, 4, 19, 30, 10).end_of_hour
   end
 
   def test_beginning_of_minute
-    assert_equal DateTime.civil(2005,2,4,19,30,0), DateTime.civil(2005,2,4,19,30,10).beginning_of_minute
+    assert_equal DateTime.civil(2005, 2, 4, 19, 30, 0), DateTime.civil(2005, 2, 4, 19, 30, 10).beginning_of_minute
   end
 
   def test_end_of_minute
-    assert_equal DateTime.civil(2005,2,4,19,30,59), DateTime.civil(2005,2,4,19,30,10).end_of_minute
+    assert_equal DateTime.civil(2005, 2, 4, 19, 30, Rational(59999999999, 1000000000)), DateTime.civil(2005, 2, 4, 19, 30, 10).end_of_minute
   end
 
   def test_end_of_month
-    assert_equal DateTime.civil(2005,3,31,23,59,59), DateTime.civil(2005,3,20,10,10,10).end_of_month
-    assert_equal DateTime.civil(2005,2,28,23,59,59), DateTime.civil(2005,2,20,10,10,10).end_of_month
-    assert_equal DateTime.civil(2005,4,30,23,59,59), DateTime.civil(2005,4,20,10,10,10).end_of_month
-  end
-
-  def test_last_year
-    assert_equal DateTime.civil(2004,6,5,10),  DateTime.civil(2005,6,5,10,0,0).last_year
+    assert_equal DateTime.civil(2005, 3, 31, 23, 59, Rational(59999999999, 1000000000)), DateTime.civil(2005, 3, 20, 10, 10, 10).end_of_month
+    assert_equal DateTime.civil(2005, 2, 28, 23, 59, Rational(59999999999, 1000000000)), DateTime.civil(2005, 2, 20, 10, 10, 10).end_of_month
+    assert_equal DateTime.civil(2005, 4, 30, 23, 59, Rational(59999999999, 1000000000)), DateTime.civil(2005, 4, 20, 10, 10, 10).end_of_month
   end
 
   def test_ago
-    assert_equal DateTime.civil(2005,2,22,10,10,9),  DateTime.civil(2005,2,22,10,10,10).ago(1)
-    assert_equal DateTime.civil(2005,2,22,9,10,10),  DateTime.civil(2005,2,22,10,10,10).ago(3600)
-    assert_equal DateTime.civil(2005,2,20,10,10,10), DateTime.civil(2005,2,22,10,10,10).ago(86400*2)
-    assert_equal DateTime.civil(2005,2,20,9,9,45),   DateTime.civil(2005,2,22,10,10,10).ago(86400*2 + 3600 + 25)
+    assert_equal DateTime.civil(2005, 2, 22, 10, 10, 9),  DateTime.civil(2005, 2, 22, 10, 10, 10).ago(1)
+    assert_equal DateTime.civil(2005, 2, 22, 9, 10, 10),  DateTime.civil(2005, 2, 22, 10, 10, 10).ago(3600)
+    assert_equal DateTime.civil(2005, 2, 20, 10, 10, 10), DateTime.civil(2005, 2, 22, 10, 10, 10).ago(86400 * 2)
+    assert_equal DateTime.civil(2005, 2, 20, 9, 9, 45),   DateTime.civil(2005, 2, 22, 10, 10, 10).ago(86400 * 2 + 3600 + 25)
   end
 
   def test_since
-    assert_equal DateTime.civil(2005,2,22,10,10,11), DateTime.civil(2005,2,22,10,10,10).since(1)
-    assert_equal DateTime.civil(2005,2,22,11,10,10), DateTime.civil(2005,2,22,10,10,10).since(3600)
-    assert_equal DateTime.civil(2005,2,24,10,10,10), DateTime.civil(2005,2,22,10,10,10).since(86400*2)
-    assert_equal DateTime.civil(2005,2,24,11,10,35), DateTime.civil(2005,2,22,10,10,10).since(86400*2 + 3600 + 25)
-    assert_equal DateTime.civil(2005,2,22,10,10,11), DateTime.civil(2005,2,22,10,10,10).since(1.333)
-    assert_equal DateTime.civil(2005,2,22,10,10,12), DateTime.civil(2005,2,22,10,10,10).since(1.667)
+    assert_equal DateTime.civil(2005, 2, 22, 10, 10, 11), DateTime.civil(2005, 2, 22, 10, 10, 10).since(1)
+    assert_equal DateTime.civil(2005, 2, 22, 11, 10, 10), DateTime.civil(2005, 2, 22, 10, 10, 10).since(3600)
+    assert_equal DateTime.civil(2005, 2, 24, 10, 10, 10), DateTime.civil(2005, 2, 22, 10, 10, 10).since(86400 * 2)
+    assert_equal DateTime.civil(2005, 2, 24, 11, 10, 35), DateTime.civil(2005, 2, 22, 10, 10, 10).since(86400 * 2 + 3600 + 25)
+    assert_equal DateTime.civil(2005, 2, 22, 10, 10, 11), DateTime.civil(2005, 2, 22, 10, 10, 10).since(1.333)
+    assert_equal DateTime.civil(2005, 2, 22, 10, 10, 12), DateTime.civil(2005, 2, 22, 10, 10, 10).since(1.667)
   end
 
   def test_change
-    assert_equal DateTime.civil(2006,2,22,15,15,10), DateTime.civil(2005,2,22,15,15,10).change(:year => 2006)
-    assert_equal DateTime.civil(2005,6,22,15,15,10), DateTime.civil(2005,2,22,15,15,10).change(:month => 6)
-    assert_equal DateTime.civil(2012,9,22,15,15,10), DateTime.civil(2005,2,22,15,15,10).change(:year => 2012, :month => 9)
-    assert_equal DateTime.civil(2005,2,22,16),       DateTime.civil(2005,2,22,15,15,10).change(:hour => 16)
-    assert_equal DateTime.civil(2005,2,22,16,45),    DateTime.civil(2005,2,22,15,15,10).change(:hour => 16, :min => 45)
-    assert_equal DateTime.civil(2005,2,22,15,45),    DateTime.civil(2005,2,22,15,15,10).change(:min => 45)
+    assert_equal DateTime.civil(2006, 2, 22, 15, 15, 10), DateTime.civil(2005, 2, 22, 15, 15, 10).change(year: 2006)
+    assert_equal DateTime.civil(2005, 6, 22, 15, 15, 10), DateTime.civil(2005, 2, 22, 15, 15, 10).change(month: 6)
+    assert_equal DateTime.civil(2012, 9, 22, 15, 15, 10), DateTime.civil(2005, 2, 22, 15, 15, 10).change(year: 2012, month: 9)
+    assert_equal DateTime.civil(2005, 2, 22, 16),         DateTime.civil(2005, 2, 22, 15, 15, 10).change(hour: 16)
+    assert_equal DateTime.civil(2005, 2, 22, 16, 45),     DateTime.civil(2005, 2, 22, 15, 15, 10).change(hour: 16, min: 45)
+    assert_equal DateTime.civil(2005, 2, 22, 15, 45),     DateTime.civil(2005, 2, 22, 15, 15, 10).change(min: 45)
+
+    # datetime with non-zero offset
+    assert_equal DateTime.civil(2005, 2, 22, 15, 15, 10, Rational(-5, 24)), DateTime.civil(2005, 2, 22, 15, 15, 10, 0).change(offset: Rational(-5, 24))
 
     # datetime with fractions of a second
-    assert_equal DateTime.civil(2005,2,1,15,15,10.7), DateTime.civil(2005,2,22,15,15,10.7).change(:day => 1)
+    assert_equal DateTime.civil(2005, 2, 1, 15, 15, 10.7), DateTime.civil(2005, 2, 22, 15, 15, 10.7).change(day: 1)
+    assert_equal DateTime.civil(2005, 1, 2, 11, 22, Rational(33000008, 1000000)), DateTime.civil(2005, 1, 2, 11, 22, 33).change(usec: 8)
+    assert_equal DateTime.civil(2005, 1, 2, 11, 22, Rational(33000008, 1000000)), DateTime.civil(2005, 1, 2, 11, 22, 33).change(nsec: 8000)
+    assert_raise(ArgumentError) { DateTime.civil(2005, 1, 2, 11, 22, 0).change(usec: 1, nsec: 1) }
+    assert_raise(ArgumentError) { DateTime.civil(2005, 1, 2, 11, 22, 0).change(usec: 1000000) }
+    assert_raise(ArgumentError) { DateTime.civil(2005, 1, 2, 11, 22, 0).change(nsec: 1000000000) }
+    assert_nothing_raised { DateTime.civil(2005, 1, 2, 11, 22, 0).change(usec: 999999) }
+    assert_nothing_raised { DateTime.civil(2005, 1, 2, 11, 22, 0).change(nsec: 999999999) }
   end
 
   def test_advance
-    assert_equal DateTime.civil(2006,2,28,15,15,10),  DateTime.civil(2005,2,28,15,15,10).advance(:years => 1)
-    assert_equal DateTime.civil(2005,6,28,15,15,10),  DateTime.civil(2005,2,28,15,15,10).advance(:months => 4)
-    assert_equal DateTime.civil(2005,3,21,15,15,10),  DateTime.civil(2005,2,28,15,15,10).advance(:weeks => 3)
-    assert_equal DateTime.civil(2005,3,5,15,15,10),   DateTime.civil(2005,2,28,15,15,10).advance(:days => 5)
-    assert_equal DateTime.civil(2012,9,28,15,15,10),  DateTime.civil(2005,2,28,15,15,10).advance(:years => 7, :months => 7)
-    assert_equal DateTime.civil(2013,10,3,15,15,10),  DateTime.civil(2005,2,28,15,15,10).advance(:years => 7, :months => 19, :days => 5)
-    assert_equal DateTime.civil(2013,10,17,15,15,10), DateTime.civil(2005,2,28,15,15,10).advance(:years => 7, :months => 19, :weeks => 2, :days => 5)
-    assert_equal DateTime.civil(2001,12,27,15,15,10), DateTime.civil(2005,2,28,15,15,10).advance(:years => -3, :months => -2, :days => -1)
-    assert_equal DateTime.civil(2005,2,28,15,15,10),  DateTime.civil(2004,2,29,15,15,10).advance(:years => 1) #leap day plus one year
-    assert_equal DateTime.civil(2005,2,28,20,15,10),  DateTime.civil(2005,2,28,15,15,10).advance(:hours => 5)
-    assert_equal DateTime.civil(2005,2,28,15,22,10),  DateTime.civil(2005,2,28,15,15,10).advance(:minutes => 7)
-    assert_equal DateTime.civil(2005,2,28,15,15,19),  DateTime.civil(2005,2,28,15,15,10).advance(:seconds => 9)
-    assert_equal DateTime.civil(2005,2,28,20,22,19),  DateTime.civil(2005,2,28,15,15,10).advance(:hours => 5, :minutes => 7, :seconds => 9)
-    assert_equal DateTime.civil(2005,2,28,10,8,1),    DateTime.civil(2005,2,28,15,15,10).advance(:hours => -5, :minutes => -7, :seconds => -9)
-    assert_equal DateTime.civil(2013,10,17,20,22,19), DateTime.civil(2005,2,28,15,15,10).advance(:years => 7, :months => 19, :weeks => 2, :days => 5, :hours => 5, :minutes => 7, :seconds => 9)
+    assert_equal DateTime.civil(2006, 2, 28, 15, 15, 10),  DateTime.civil(2005, 2, 28, 15, 15, 10).advance(years: 1)
+    assert_equal DateTime.civil(2005, 6, 28, 15, 15, 10),  DateTime.civil(2005, 2, 28, 15, 15, 10).advance(months: 4)
+    assert_equal DateTime.civil(2005, 3, 21, 15, 15, 10),  DateTime.civil(2005, 2, 28, 15, 15, 10).advance(weeks: 3)
+    assert_equal DateTime.civil(2005, 3, 5, 15, 15, 10),   DateTime.civil(2005, 2, 28, 15, 15, 10).advance(days: 5)
+    assert_equal DateTime.civil(2012, 9, 28, 15, 15, 10),  DateTime.civil(2005, 2, 28, 15, 15, 10).advance(years: 7, months: 7)
+    assert_equal DateTime.civil(2013, 10, 3, 15, 15, 10),  DateTime.civil(2005, 2, 28, 15, 15, 10).advance(years: 7, months: 19, days: 5)
+    assert_equal DateTime.civil(2013, 10, 17, 15, 15, 10), DateTime.civil(2005, 2, 28, 15, 15, 10).advance(years: 7, months: 19, weeks: 2, days: 5)
+    assert_equal DateTime.civil(2001, 12, 27, 15, 15, 10), DateTime.civil(2005, 2, 28, 15, 15, 10).advance(years: -3, months: -2, days: -1)
+    assert_equal DateTime.civil(2005, 2, 28, 15, 15, 10),  DateTime.civil(2004, 2, 29, 15, 15, 10).advance(years: 1) # leap day plus one year
+    assert_equal DateTime.civil(2005, 2, 28, 20, 15, 10),  DateTime.civil(2005, 2, 28, 15, 15, 10).advance(hours: 5)
+    assert_equal DateTime.civil(2005, 2, 28, 15, 22, 10),  DateTime.civil(2005, 2, 28, 15, 15, 10).advance(minutes: 7)
+    assert_equal DateTime.civil(2005, 2, 28, 15, 15, 19),  DateTime.civil(2005, 2, 28, 15, 15, 10).advance(seconds: 9)
+    assert_equal DateTime.civil(2005, 2, 28, 20, 22, 19),  DateTime.civil(2005, 2, 28, 15, 15, 10).advance(hours: 5, minutes: 7, seconds: 9)
+    assert_equal DateTime.civil(2005, 2, 28, 10, 8, 1),    DateTime.civil(2005, 2, 28, 15, 15, 10).advance(hours: -5, minutes: -7, seconds: -9)
+    assert_equal DateTime.civil(2013, 10, 17, 20, 22, 19), DateTime.civil(2005, 2, 28, 15, 15, 10).advance(years: 7, months: 19, weeks: 2, days: 5, hours: 5, minutes: 7, seconds: 9)
   end
 
   def test_advance_partial_days
-    assert_equal DateTime.civil(2012,9,29,13,15,10),  DateTime.civil(2012,9,28,1,15,10).advance(:days => 1.5)
-    assert_equal DateTime.civil(2012,9,28,13,15,10),  DateTime.civil(2012,9,28,1,15,10).advance(:days => 0.5)
-    assert_equal DateTime.civil(2012,10,29,13,15,10), DateTime.civil(2012,9,28,1,15,10).advance(:days => 1.5, :months => 1)
+    assert_equal DateTime.civil(2012, 9, 29, 13, 15, 10),  DateTime.civil(2012, 9, 28, 1, 15, 10).advance(days: 1.5)
+    assert_equal DateTime.civil(2012, 9, 28, 13, 15, 10),  DateTime.civil(2012, 9, 28, 1, 15, 10).advance(days: 0.5)
+    assert_equal DateTime.civil(2012, 10, 29, 13, 15, 10), DateTime.civil(2012, 9, 28, 1, 15, 10).advance(days: 1.5, months: 1)
   end
 
   def test_advanced_processes_first_the_date_deltas_and_then_the_time_deltas
     # If the time deltas were processed first, the following datetimes would be advanced to 2010/04/01 instead.
-    assert_equal DateTime.civil(2010, 3, 29), DateTime.civil(2010, 2, 28, 23, 59, 59).advance(:months => 1, :seconds => 1)
-    assert_equal DateTime.civil(2010, 3, 29), DateTime.civil(2010, 2, 28, 23, 59).advance(:months => 1, :minutes => 1)
-    assert_equal DateTime.civil(2010, 3, 29), DateTime.civil(2010, 2, 28, 23).advance(:months => 1, :hours => 1)
-    assert_equal DateTime.civil(2010, 3, 29), DateTime.civil(2010, 2, 28, 22, 58, 59).advance(:months => 1, :hours => 1, :minutes => 1, :seconds => 1)
+    assert_equal DateTime.civil(2010, 3, 29), DateTime.civil(2010, 2, 28, 23, 59, 59).advance(months: 1, seconds: 1)
+    assert_equal DateTime.civil(2010, 3, 29), DateTime.civil(2010, 2, 28, 23, 59).advance(months: 1, minutes: 1)
+    assert_equal DateTime.civil(2010, 3, 29), DateTime.civil(2010, 2, 28, 23).advance(months: 1, hours: 1)
+    assert_equal DateTime.civil(2010, 3, 29), DateTime.civil(2010, 2, 28, 22, 58, 59).advance(months: 1, hours: 1, minutes: 1, seconds: 1)
   end
 
   def test_last_week
-    assert_equal DateTime.civil(2005,2,21), DateTime.civil(2005,3,1,15,15,10).last_week
-    assert_equal DateTime.civil(2005,2,22), DateTime.civil(2005,3,1,15,15,10).last_week(:tuesday)
-    assert_equal DateTime.civil(2005,2,25), DateTime.civil(2005,3,1,15,15,10).last_week(:friday)
-    assert_equal DateTime.civil(2006,10,30), DateTime.civil(2006,11,6,0,0,0).last_week
-    assert_equal DateTime.civil(2006,11,15), DateTime.civil(2006,11,23,0,0,0).last_week(:wednesday)
+    assert_equal DateTime.civil(2005, 2, 21), DateTime.civil(2005, 3, 1, 15, 15, 10).last_week
+    assert_equal DateTime.civil(2005, 2, 22), DateTime.civil(2005, 3, 1, 15, 15, 10).last_week(:tuesday)
+    assert_equal DateTime.civil(2005, 2, 25), DateTime.civil(2005, 3, 1, 15, 15, 10).last_week(:friday)
+    assert_equal DateTime.civil(2006, 10, 30), DateTime.civil(2006, 11, 6, 0, 0, 0).last_week
+    assert_equal DateTime.civil(2006, 11, 15), DateTime.civil(2006, 11, 23, 0, 0, 0).last_week(:wednesday)
   end
 
   def test_date_time_should_have_correct_last_week_for_leap_year
     assert_equal DateTime.civil(2016, 2, 29), DateTime.civil(2016, 3, 7).last_week
   end
 
-  def test_last_month_on_31st
-    assert_equal DateTime.civil(2004, 2, 29), DateTime.civil(2004, 3, 31).last_month
-  end
-
   def test_last_quarter_on_31st
     assert_equal DateTime.civil(2004, 2, 29), DateTime.civil(2004, 5, 31).last_quarter
   end
@@ -233,56 +237,56 @@ class DateTimeExtCalculationsTest < ActiveSupport::TestCase
 
   def test_today_with_offset
     Date.stub(:current, Date.new(2000, 1, 1)) do
-      assert_equal false, DateTime.civil(1999,12,31,23,59,59, Rational(-18000, 86400)).today?
-      assert_equal true,  DateTime.civil(2000,1,1,0,0,0, Rational(-18000, 86400)).today?
-      assert_equal true,  DateTime.civil(2000,1,1,23,59,59, Rational(-18000, 86400)).today?
-      assert_equal false, DateTime.civil(2000,1,2,0,0,0, Rational(-18000, 86400)).today?
+      assert_equal false, DateTime.civil(1999, 12, 31, 23, 59, 59, Rational(-18000, 86400)).today?
+      assert_equal true,  DateTime.civil(2000, 1, 1, 0, 0, 0, Rational(-18000, 86400)).today?
+      assert_equal true,  DateTime.civil(2000, 1, 1, 23, 59, 59, Rational(-18000, 86400)).today?
+      assert_equal false, DateTime.civil(2000, 1, 2, 0, 0, 0, Rational(-18000, 86400)).today?
     end
   end
 
   def test_today_without_offset
     Date.stub(:current, Date.new(2000, 1, 1)) do
-      assert_equal false, DateTime.civil(1999,12,31,23,59,59).today?
-      assert_equal true,  DateTime.civil(2000,1,1,0).today?
-      assert_equal true,  DateTime.civil(2000,1,1,23,59,59).today?
-      assert_equal false, DateTime.civil(2000,1,2,0).today?
+      assert_equal false, DateTime.civil(1999, 12, 31, 23, 59, 59).today?
+      assert_equal true,  DateTime.civil(2000, 1, 1, 0).today?
+      assert_equal true,  DateTime.civil(2000, 1, 1, 23, 59, 59).today?
+      assert_equal false, DateTime.civil(2000, 1, 2, 0).today?
     end
   end
 
   def test_past_with_offset
-    DateTime.stub(:current, DateTime.civil(2005,2,10,15,30,45, Rational(-18000, 86400))) do
-      assert_equal true,  DateTime.civil(2005,2,10,15,30,44, Rational(-18000, 86400)).past?
-      assert_equal false,  DateTime.civil(2005,2,10,15,30,45, Rational(-18000, 86400)).past?
-      assert_equal false,  DateTime.civil(2005,2,10,15,30,46, Rational(-18000, 86400)).past?
+    DateTime.stub(:current, DateTime.civil(2005, 2, 10, 15, 30, 45, Rational(-18000, 86400))) do
+      assert_equal true,  DateTime.civil(2005, 2, 10, 15, 30, 44, Rational(-18000, 86400)).past?
+      assert_equal false,  DateTime.civil(2005, 2, 10, 15, 30, 45, Rational(-18000, 86400)).past?
+      assert_equal false,  DateTime.civil(2005, 2, 10, 15, 30, 46, Rational(-18000, 86400)).past?
     end
   end
 
   def test_past_without_offset
-    DateTime.stub(:current, DateTime.civil(2005,2,10,15,30,45, Rational(-18000, 86400))) do
-      assert_equal true,  DateTime.civil(2005,2,10,20,30,44).past?
-      assert_equal false,  DateTime.civil(2005,2,10,20,30,45).past?
-      assert_equal false,  DateTime.civil(2005,2,10,20,30,46).past?
+    DateTime.stub(:current, DateTime.civil(2005, 2, 10, 15, 30, 45, Rational(-18000, 86400))) do
+      assert_equal true,  DateTime.civil(2005, 2, 10, 20, 30, 44).past?
+      assert_equal false,  DateTime.civil(2005, 2, 10, 20, 30, 45).past?
+      assert_equal false,  DateTime.civil(2005, 2, 10, 20, 30, 46).past?
     end
   end
 
   def test_future_with_offset
-    DateTime.stub(:current, DateTime.civil(2005,2,10,15,30,45, Rational(-18000, 86400))) do
-      assert_equal false,  DateTime.civil(2005,2,10,15,30,44, Rational(-18000, 86400)).future?
-      assert_equal false,  DateTime.civil(2005,2,10,15,30,45, Rational(-18000, 86400)).future?
-      assert_equal true,  DateTime.civil(2005,2,10,15,30,46, Rational(-18000, 86400)).future?
+    DateTime.stub(:current, DateTime.civil(2005, 2, 10, 15, 30, 45, Rational(-18000, 86400))) do
+      assert_equal false,  DateTime.civil(2005, 2, 10, 15, 30, 44, Rational(-18000, 86400)).future?
+      assert_equal false,  DateTime.civil(2005, 2, 10, 15, 30, 45, Rational(-18000, 86400)).future?
+      assert_equal true,  DateTime.civil(2005, 2, 10, 15, 30, 46, Rational(-18000, 86400)).future?
     end
   end
 
   def test_future_without_offset
-    DateTime.stub(:current, DateTime.civil(2005,2,10,15,30,45, Rational(-18000, 86400))) do
-      assert_equal false,  DateTime.civil(2005,2,10,20,30,44).future?
-      assert_equal false,  DateTime.civil(2005,2,10,20,30,45).future?
-      assert_equal true,  DateTime.civil(2005,2,10,20,30,46).future?
+    DateTime.stub(:current, DateTime.civil(2005, 2, 10, 15, 30, 45, Rational(-18000, 86400))) do
+      assert_equal false,  DateTime.civil(2005, 2, 10, 20, 30, 44).future?
+      assert_equal false,  DateTime.civil(2005, 2, 10, 20, 30, 45).future?
+      assert_equal true,  DateTime.civil(2005, 2, 10, 20, 30, 46).future?
     end
   end
 
   def test_current_returns_date_today_when_zone_is_not_set
-    with_env_tz 'US/Eastern' do
+    with_env_tz "US/Eastern" do
       Time.stub(:now, Time.local(1999, 12, 31, 23, 59, 59)) do
         assert_equal DateTime.new(1999, 12, 31, 23, 59, 59, Rational(-18000, 86400)), DateTime.current
       end
@@ -290,8 +294,8 @@ class DateTimeExtCalculationsTest < ActiveSupport::TestCase
   end
 
   def test_current_returns_time_zone_today_when_zone_is_set
-    Time.zone = ActiveSupport::TimeZone['Eastern Time (US & Canada)']
-    with_env_tz 'US/Eastern' do
+    Time.zone = ActiveSupport::TimeZone["Eastern Time (US & Canada)"]
+    with_env_tz "US/Eastern" do
       Time.stub(:now, Time.local(1999, 12, 31, 23, 59, 59)) do
         assert_equal DateTime.new(1999, 12, 31, 23, 59, 59, Rational(-18000, 86400)), DateTime.current
       end
@@ -305,7 +309,7 @@ class DateTimeExtCalculationsTest < ActiveSupport::TestCase
   end
 
   def test_current_with_time_zone
-    with_env_tz 'US/Eastern' do
+    with_env_tz "US/Eastern" do
       assert_kind_of DateTime, DateTime.current
     end
   end
@@ -318,6 +322,10 @@ class DateTimeExtCalculationsTest < ActiveSupport::TestCase
     assert DateTime.new.acts_like_time?
   end
 
+  def test_blank?
+    assert_not DateTime.new.blank?
+  end
+
   def test_utc?
     assert_equal true, DateTime.civil(2005, 2, 21, 10, 11, 12).utc?
     assert_equal true, DateTime.civil(2005, 2, 21, 10, 11, 12, 0).utc?
@@ -329,8 +337,8 @@ class DateTimeExtCalculationsTest < ActiveSupport::TestCase
     assert_equal 0, DateTime.civil(2005, 2, 21, 10, 11, 12).utc_offset
     assert_equal 0, DateTime.civil(2005, 2, 21, 10, 11, 12, 0).utc_offset
     assert_equal 21600, DateTime.civil(2005, 2, 21, 10, 11, 12, 0.25).utc_offset
-    assert_equal( -21600, DateTime.civil(2005, 2, 21, 10, 11, 12, -0.25).utc_offset )
-    assert_equal( -18000, DateTime.civil(2005, 2, 21, 10, 11, 12, Rational(-5, 24)).utc_offset )
+    assert_equal(-21600, DateTime.civil(2005, 2, 21, 10, 11, 12, -0.25).utc_offset)
+    assert_equal(-18000, DateTime.civil(2005, 2, 21, 10, 11, 12, Rational(-5, 24)).utc_offset)
   end
 
   def test_utc
@@ -343,15 +351,15 @@ class DateTimeExtCalculationsTest < ActiveSupport::TestCase
   end
 
   def test_formatted_offset_with_utc
-    assert_equal '+00:00', DateTime.civil(2000).formatted_offset
-    assert_equal '+0000', DateTime.civil(2000).formatted_offset(false)
-    assert_equal 'UTC', DateTime.civil(2000).formatted_offset(true, 'UTC')
+    assert_equal "+00:00", DateTime.civil(2000).formatted_offset
+    assert_equal "+0000", DateTime.civil(2000).formatted_offset(false)
+    assert_equal "UTC", DateTime.civil(2000).formatted_offset(true, "UTC")
   end
 
   def test_formatted_offset_with_local
     dt = DateTime.civil(2005, 2, 21, 10, 11, 12, Rational(-5, 24))
-    assert_equal '-05:00', dt.formatted_offset
-    assert_equal '-0500', dt.formatted_offset(false)
+    assert_equal "-05:00", dt.formatted_offset
+    assert_equal "-0500", dt.formatted_offset(false)
   end
 
   def test_compare_with_time
@@ -367,16 +375,16 @@ class DateTimeExtCalculationsTest < ActiveSupport::TestCase
   end
 
   def test_compare_with_time_with_zone
-    assert_equal  1, DateTime.civil(2000) <=> ActiveSupport::TimeWithZone.new( Time.utc(1999, 12, 31, 23, 59, 59), ActiveSupport::TimeZone['UTC'] )
-    assert_equal  0, DateTime.civil(2000) <=> ActiveSupport::TimeWithZone.new( Time.utc(2000, 1, 1, 0, 0, 0), ActiveSupport::TimeZone['UTC'] )
-    assert_equal(-1, DateTime.civil(2000) <=> ActiveSupport::TimeWithZone.new( Time.utc(2000, 1, 1, 0, 0, 1), ActiveSupport::TimeZone['UTC'] ))
+    assert_equal  1, DateTime.civil(2000) <=> ActiveSupport::TimeWithZone.new(Time.utc(1999, 12, 31, 23, 59, 59), ActiveSupport::TimeZone["UTC"])
+    assert_equal  0, DateTime.civil(2000) <=> ActiveSupport::TimeWithZone.new(Time.utc(2000, 1, 1, 0, 0, 0), ActiveSupport::TimeZone["UTC"])
+    assert_equal(-1, DateTime.civil(2000) <=> ActiveSupport::TimeWithZone.new(Time.utc(2000, 1, 1, 0, 0, 1), ActiveSupport::TimeZone["UTC"]))
   end
 
   def test_compare_with_string
     assert_equal   1, DateTime.civil(2000) <=> Time.utc(1999, 12, 31, 23, 59, 59).to_s
     assert_equal   0, DateTime.civil(2000) <=> Time.utc(2000, 1, 1, 0, 0, 0).to_s
-    assert_equal( -1, DateTime.civil(2000) <=> Time.utc(2000, 1, 1, 0, 0, 1).to_s)
-    assert_equal nil, DateTime.civil(2000) <=> "Invalid as Time"
+    assert_equal(-1, DateTime.civil(2000) <=> Time.utc(2000, 1, 1, 0, 0, 1).to_s)
+    assert_nil DateTime.civil(2000) <=> "Invalid as Time"
   end
 
   def test_compare_with_integer
@@ -399,27 +407,27 @@ class DateTimeExtCalculationsTest < ActiveSupport::TestCase
 
   def test_to_f
     assert_equal 946684800.0, DateTime.civil(2000).to_f
-    assert_equal 946684800.0, DateTime.civil(1999,12,31,19,0,0,Rational(-5,24)).to_f
-    assert_equal 946684800.5, DateTime.civil(1999,12,31,19,0,0.5,Rational(-5,24)).to_f
+    assert_equal 946684800.0, DateTime.civil(1999, 12, 31, 19, 0, 0, Rational(-5, 24)).to_f
+    assert_equal 946684800.5, DateTime.civil(1999, 12, 31, 19, 0, 0.5, Rational(-5, 24)).to_f
   end
 
   def test_to_i
     assert_equal 946684800, DateTime.civil(2000).to_i
-    assert_equal 946684800, DateTime.civil(1999,12,31,19,0,0,Rational(-5,24)).to_i
+    assert_equal 946684800, DateTime.civil(1999, 12, 31, 19, 0, 0, Rational(-5, 24)).to_i
   end
 
   def test_usec
     assert_equal 0, DateTime.civil(2000).usec
-    assert_equal 500000, DateTime.civil(2000, 1, 1, 0, 0, Rational(1,2)).usec
+    assert_equal 500000, DateTime.civil(2000, 1, 1, 0, 0, Rational(1, 2)).usec
   end
 
   def test_nsec
     assert_equal 0, DateTime.civil(2000).nsec
-    assert_equal 500000000, DateTime.civil(2000, 1, 1, 0, 0, Rational(1,2)).nsec
+    assert_equal 500000000, DateTime.civil(2000, 1, 1, 0, 0, Rational(1, 2)).nsec
   end
 
   def test_subsec
     assert_equal 0, DateTime.civil(2000).subsec
-    assert_equal Rational(1,2), DateTime.civil(2000, 1, 1, 0, 0, Rational(1,2)).subsec
+    assert_equal Rational(1, 2), DateTime.civil(2000, 1, 1, 0, 0, Rational(1, 2)).subsec
   end
 end
diff --git a/activesupport/test/core_ext/digest/uuid_test.rb b/activesupport/test/core_ext/digest/uuid_test.rb
index 08e0a1d6e1..94cb7d9418 100644
--- a/activesupport/test/core_ext/digest/uuid_test.rb
+++ b/activesupport/test/core_ext/digest/uuid_test.rb
@@ -1,5 +1,7 @@
-require 'abstract_unit'
-require 'active_support/core_ext/digest/uuid'
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "active_support/core_ext/digest/uuid"
 
 class DigestUUIDExt < ActiveSupport::TestCase
   def test_v3_uuids
@@ -18,7 +20,7 @@ class DigestUUIDExt < ActiveSupport::TestCase
 
   def test_invalid_hash_class
     assert_raise ArgumentError do
-      Digest::UUID.uuid_from_hash(Digest::SHA2, Digest::UUID::OID_NAMESPACE, '1.2.3')
+      Digest::UUID.uuid_from_hash(Digest::SHA2, Digest::UUID::OID_NAMESPACE, "1.2.3")
     end
   end
 end
diff --git a/activesupport/test/core_ext/duration_test.rb b/activesupport/test/core_ext/duration_test.rb
index 502e2811fa..4a02f27def 100644
--- a/activesupport/test/core_ext/duration_test.rb
+++ b/activesupport/test/core_ext/duration_test.rb
@@ -1,8 +1,10 @@
-require 'abstract_unit'
-require 'active_support/inflector'
-require 'active_support/time'
-require 'active_support/json'
-require 'time_zone_test_helpers'
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "active_support/inflector"
+require "active_support/time"
+require "active_support/json"
+require "time_zone_test_helpers"
 
 class DurationTest < ActiveSupport::TestCase
   include TimeZoneTestHelpers
@@ -21,7 +23,7 @@ class DurationTest < ActiveSupport::TestCase
   end
 
   def test_instance_of
-    assert 1.minute.instance_of?(Fixnum)
+    assert 1.minute.instance_of?(1.class)
     assert 2.days.instance_of?(ActiveSupport::Duration)
     assert !3.second.instance_of?(Numeric)
   end
@@ -29,14 +31,14 @@ class DurationTest < ActiveSupport::TestCase
   def test_threequals
     assert ActiveSupport::Duration === 1.day
     assert !(ActiveSupport::Duration === 1.day.to_i)
-    assert !(ActiveSupport::Duration === 'foo')
+    assert !(ActiveSupport::Duration === "foo")
   end
 
   def test_equals
     assert 1.day == 1.day
     assert 1.day == 1.day.to_i
     assert 1.day.to_i == 1.day
-    assert !(1.day == 'foo')
+    assert !(1.day == "foo")
   end
 
   def test_to_s
@@ -54,28 +56,30 @@ class DurationTest < ActiveSupport::TestCase
     assert !1.eql?(1.second)
     assert 1.minute.eql?(180.seconds - 2.minutes)
     assert !1.minute.eql?(60)
-    assert !1.minute.eql?('foo')
+    assert !1.minute.eql?("foo")
   end
 
   def test_inspect
-    assert_equal '0 seconds',                       0.seconds.inspect
-    assert_equal '1 month',                         1.month.inspect
-    assert_equal '1 month and 1 day',               (1.month + 1.day).inspect
-    assert_equal '6 months and -2 days',            (6.months - 2.days).inspect
-    assert_equal '10 seconds',                      10.seconds.inspect
-    assert_equal '10 years, 2 months, and 1 day',   (10.years + 2.months + 1.day).inspect
-    assert_equal '10 years, 2 months, and 1 day',   (10.years + 1.month  + 1.day + 1.month).inspect
-    assert_equal '10 years, 2 months, and 1 day',   (1.day + 10.years + 2.months).inspect
-    assert_equal '7 days',                          7.days.inspect
-    assert_equal '1 week',                          1.week.inspect
-    assert_equal '2 weeks',                         1.fortnight.inspect
+    assert_equal "0 seconds",                       0.seconds.inspect
+    assert_equal "1 month",                         1.month.inspect
+    assert_equal "1 month and 1 day",               (1.month + 1.day).inspect
+    assert_equal "6 months and -2 days",            (6.months - 2.days).inspect
+    assert_equal "10 seconds",                      10.seconds.inspect
+    assert_equal "10 years, 2 months, and 1 day",   (10.years + 2.months + 1.day).inspect
+    assert_equal "10 years, 2 months, and 1 day",   (10.years + 1.month  + 1.day + 1.month).inspect
+    assert_equal "10 years, 2 months, and 1 day",   (1.day + 10.years + 2.months).inspect
+    assert_equal "7 days",                          7.days.inspect
+    assert_equal "1 week",                          1.week.inspect
+    assert_equal "2 weeks",                         1.fortnight.inspect
+    assert_equal "0 seconds",                       (10 % 5.seconds).inspect
+    assert_equal "10 minutes",                      (10.minutes + 0.seconds).inspect
   end
 
   def test_inspect_locale
     current_locale = I18n.default_locale
     I18n.default_locale = :de
-    I18n.backend.store_translations(:de, { support: { array: { last_word_connector: ' und ' } } })
-    assert_equal '10 years, 1 month und 1 day', (10.years + 1.month  + 1.day).inspect
+    I18n.backend.store_translations(:de, support: { array: { last_word_connector: " und " } })
+    assert_equal "10 years, 1 month und 1 day", (10.years + 1.month + 1.day).inspect
   ensure
     I18n.default_locale = current_locale
   end
@@ -84,12 +88,81 @@ class DurationTest < ActiveSupport::TestCase
     assert_nothing_raised { Date.today - Date.today }
   end
 
+  def test_plus
+    assert_equal 2.seconds, 1.second + 1.second
+    assert_instance_of ActiveSupport::Duration, 1.second + 1.second
+    assert_equal 2.seconds, 1.second + 1
+    assert_instance_of ActiveSupport::Duration, 1.second + 1
+  end
+
+  def test_minus
+    assert_equal 1.second, 2.seconds - 1.second
+    assert_instance_of ActiveSupport::Duration, 2.seconds - 1.second
+    assert_equal 1.second, 2.seconds - 1
+    assert_instance_of ActiveSupport::Duration, 2.seconds - 1
+    assert_equal 1.second, 2 - 1.second
+    assert_instance_of ActiveSupport::Duration, 2.seconds - 1
+  end
+
+  def test_multiply
+    assert_equal 7.days, 1.day * 7
+    assert_instance_of ActiveSupport::Duration, 1.day * 7
+    assert_equal 86400, 1.day * 1.second
+  end
+
+  def test_divide
+    assert_equal 1.day, 7.days / 7
+    assert_instance_of ActiveSupport::Duration, 7.days / 7
+
+    assert_equal 1.hour, 1.day / 24
+    assert_instance_of ActiveSupport::Duration, 1.day / 24
+
+    assert_equal 24, 86400 / 1.hour
+    assert_kind_of Integer, 86400 / 1.hour
+
+    assert_equal 24, 1.day / 1.hour
+    assert_kind_of Integer, 1.day / 1.hour
+
+    assert_equal 1, 1.day / 1.day
+    assert_kind_of Integer, 1.day / 1.hour
+  end
+
+  def test_modulo
+    assert_equal 1.minute, 5.minutes % 120
+    assert_instance_of ActiveSupport::Duration, 5.minutes % 120
+
+    assert_equal 1.minute, 5.minutes % 2.minutes
+    assert_instance_of ActiveSupport::Duration, 5.minutes % 2.minutes
+
+    assert_equal 1.minute, 5.minutes % 120.seconds
+    assert_instance_of ActiveSupport::Duration, 5.minutes % 120.seconds
+
+    assert_equal 5.minutes, 5.minutes % 1.hour
+    assert_instance_of ActiveSupport::Duration, 5.minutes % 1.hour
+
+    assert_equal 1.day, 36.days % 604800
+    assert_instance_of ActiveSupport::Duration, 36.days % 604800
+
+    assert_equal 1.day, 36.days % 7.days
+    assert_instance_of ActiveSupport::Duration, 36.days % 7.days
+
+    assert_equal 800.seconds, 8000 % 1.hour
+    assert_instance_of ActiveSupport::Duration, 8000 % 1.hour
+
+    assert_equal 1.month, 13.months % 1.year
+    assert_instance_of ActiveSupport::Duration, 13.months % 1.year
+  end
+
+  def test_date_added_with_multiplied_duration
+    assert_equal Date.civil(2017, 1, 3), Date.civil(2017, 1, 1) + 1.day * 2
+  end
+
   def test_plus_with_time
     assert_equal 1 + 1.second, 1.second + 1, "Duration + Numeric should == Numeric + Duration"
   end
 
   def test_time_plus_duration_returns_same_time_datatype
-    twz = ActiveSupport::TimeWithZone.new(nil, ActiveSupport::TimeZone['Moscow'] , Time.utc(2016,4,28,00,45))
+    twz = ActiveSupport::TimeWithZone.new(nil, ActiveSupport::TimeZone["Moscow"], Time.utc(2016, 4, 28, 00, 45))
     now = Time.now.utc
     %w( second minute hour day week month year ).each do |unit|
       assert_equal((now + 1.send(unit)).class, Time, "Time + 1.#{unit} must be Time")
@@ -99,7 +172,7 @@ class DurationTest < ActiveSupport::TestCase
 
   def test_argument_error
     e = assert_raise ArgumentError do
-      1.second.ago('')
+      1.second.ago("")
     end
     assert_equal 'expected a time or date, got ""', e.message, "ensure ArgumentError is not being raised by dependencies.rb"
   end
@@ -149,54 +222,67 @@ class DurationTest < ActiveSupport::TestCase
 
   def test_since_and_ago_anchored_to_time_now_when_time_zone_is_not_set
     Time.zone = nil
-    with_env_tz 'US/Eastern' do
+    with_env_tz "US/Eastern" do
       Time.stub(:now, Time.local(2000)) do
         # since
         assert_not_instance_of ActiveSupport::TimeWithZone, 5.seconds.since
-        assert_equal Time.local(2000,1,1,0,0,5), 5.seconds.since
+        assert_equal Time.local(2000, 1, 1, 0, 0, 5), 5.seconds.since
         # ago
         assert_not_instance_of ActiveSupport::TimeWithZone, 5.seconds.ago
-        assert_equal Time.local(1999,12,31,23,59,55), 5.seconds.ago
+        assert_equal Time.local(1999, 12, 31, 23, 59, 55), 5.seconds.ago
       end
     end
   end
 
   def test_since_and_ago_anchored_to_time_zone_now_when_time_zone_is_set
-    Time.zone = ActiveSupport::TimeZone['Eastern Time (US & Canada)']
-    with_env_tz 'US/Eastern' do
+    Time.zone = ActiveSupport::TimeZone["Eastern Time (US & Canada)"]
+    with_env_tz "US/Eastern" do
       Time.stub(:now, Time.local(2000)) do
         # since
         assert_instance_of ActiveSupport::TimeWithZone, 5.seconds.since
-        assert_equal Time.utc(2000,1,1,0,0,5), 5.seconds.since.time
-        assert_equal 'Eastern Time (US & Canada)', 5.seconds.since.time_zone.name
+        assert_equal Time.utc(2000, 1, 1, 0, 0, 5), 5.seconds.since.time
+        assert_equal "Eastern Time (US & Canada)", 5.seconds.since.time_zone.name
         # ago
         assert_instance_of ActiveSupport::TimeWithZone, 5.seconds.ago
-        assert_equal Time.utc(1999,12,31,23,59,55), 5.seconds.ago.time
-        assert_equal 'Eastern Time (US & Canada)', 5.seconds.ago.time_zone.name
+        assert_equal Time.utc(1999, 12, 31, 23, 59, 55), 5.seconds.ago.time
+        assert_equal "Eastern Time (US & Canada)", 5.seconds.ago.time_zone.name
       end
     end
   ensure
     Time.zone = nil
   end
 
+  def test_before_and_afer
+    t = Time.local(2000)
+    assert_equal t + 1, 1.second.after(t)
+    assert_equal t - 1, 1.second.before(t)
+  end
+
+  def test_before_and_after_without_argument
+    Time.stub(:now, Time.local(2000)) do
+      assert_equal Time.now - 1.second, 1.second.before
+      assert_equal Time.now + 1.second, 1.second.after
+    end
+  end
+
   def test_adding_hours_across_dst_boundary
-    with_env_tz 'CET' do
-      assert_equal Time.local(2009,3,29,0,0,0) + 24.hours, Time.local(2009,3,30,1,0,0)
+    with_env_tz "CET" do
+      assert_equal Time.local(2009, 3, 29, 0, 0, 0) + 24.hours, Time.local(2009, 3, 30, 1, 0, 0)
     end
   end
 
   def test_adding_day_across_dst_boundary
-    with_env_tz 'CET' do
-      assert_equal Time.local(2009,3,29,0,0,0) + 1.day, Time.local(2009,3,30,0,0,0)
+    with_env_tz "CET" do
+      assert_equal Time.local(2009, 3, 29, 0, 0, 0) + 1.day, Time.local(2009, 3, 30, 0, 0, 0)
     end
   end
 
   def test_delegation_with_block_works
     counter = 0
     assert_nothing_raised do
-      1.minute.times {counter += 1}
+      1.minute.times { counter += 1 }
     end
-    assert_equal counter, 60
+    assert_equal 60, counter
   end
 
   def test_as_json
@@ -204,12 +290,16 @@ class DurationTest < ActiveSupport::TestCase
   end
 
   def test_to_json
-    assert_equal '172800', 2.days.to_json
+    assert_equal "172800", 2.days.to_json
   end
 
   def test_case_when
-    cased = case 1.day when 1.day then "ok" end
-    assert_equal cased, "ok"
+    cased = \
+      case 1.day
+      when 1.day
+        "ok"
+      end
+    assert_equal "ok", cased
   end
 
   def test_respond_to
@@ -233,6 +323,191 @@ class DurationTest < ActiveSupport::TestCase
     assert_equal(1, (61 <=> 1.minute))
   end
 
+  def test_implicit_coercion
+    assert_equal 2.days, 2 * 1.day
+    assert_instance_of ActiveSupport::Duration, 2 * 1.day
+    assert_equal Time.utc(2017, 1, 3), Time.utc(2017, 1, 1) + 2 * 1.day
+    assert_equal Date.civil(2017, 1, 3), Date.civil(2017, 1, 1) + 2 * 1.day
+  end
+
+  def test_scalar_coerce
+    scalar = ActiveSupport::Duration::Scalar.new(10)
+    assert_instance_of ActiveSupport::Duration::Scalar, 10 + scalar
+    assert_instance_of ActiveSupport::Duration, 10.seconds + scalar
+  end
+
+  def test_scalar_delegations
+    scalar = ActiveSupport::Duration::Scalar.new(10)
+    assert_kind_of Float, scalar.to_f
+    assert_kind_of Integer, scalar.to_i
+    assert_kind_of String, scalar.to_s
+  end
+
+  def test_scalar_unary_minus
+    scalar = ActiveSupport::Duration::Scalar.new(10)
+
+    assert_equal(-10, -scalar)
+    assert_instance_of ActiveSupport::Duration::Scalar, -scalar
+  end
+
+  def test_scalar_compare
+    scalar = ActiveSupport::Duration::Scalar.new(10)
+
+    assert_equal(1, scalar <=> 5)
+    assert_equal(0, scalar <=> 10)
+    assert_equal(-1, scalar <=> 15)
+    assert_nil(scalar <=> "foo")
+  end
+
+  def test_scalar_plus
+    scalar = ActiveSupport::Duration::Scalar.new(10)
+
+    assert_equal 20, 10 + scalar
+    assert_instance_of ActiveSupport::Duration::Scalar, 10 + scalar
+    assert_equal 20, scalar + 10
+    assert_instance_of ActiveSupport::Duration::Scalar, scalar + 10
+    assert_equal 20, 10.seconds + scalar
+    assert_instance_of ActiveSupport::Duration, 10.seconds + scalar
+    assert_equal 20, scalar + 10.seconds
+    assert_instance_of ActiveSupport::Duration, scalar + 10.seconds
+
+    exception = assert_raises(TypeError) do
+      scalar + "foo"
+    end
+
+    assert_equal "no implicit conversion of String into ActiveSupport::Duration::Scalar", exception.message
+  end
+
+  def test_scalar_plus_parts
+    scalar = ActiveSupport::Duration::Scalar.new(10)
+
+    assert_equal({ days: 1, seconds: 10 }, (scalar + 1.day).parts)
+    assert_equal({ days: -1, seconds: 10 }, (scalar + -1.day).parts)
+  end
+
+  def test_scalar_minus
+    scalar = ActiveSupport::Duration::Scalar.new(10)
+
+    assert_equal 10, 20 - scalar
+    assert_instance_of ActiveSupport::Duration::Scalar, 20 - scalar
+    assert_equal 5, scalar - 5
+    assert_instance_of ActiveSupport::Duration::Scalar, scalar - 5
+    assert_equal 10, 20.seconds - scalar
+    assert_instance_of ActiveSupport::Duration, 20.seconds - scalar
+    assert_equal 5, scalar - 5.seconds
+    assert_instance_of ActiveSupport::Duration, scalar - 5.seconds
+
+    assert_equal({ days: -1, seconds: 10 }, (scalar - 1.day).parts)
+    assert_equal({ days: 1, seconds: 10 }, (scalar - -1.day).parts)
+
+    exception = assert_raises(TypeError) do
+      scalar - "foo"
+    end
+
+    assert_equal "no implicit conversion of String into ActiveSupport::Duration::Scalar", exception.message
+  end
+
+  def test_scalar_minus_parts
+    scalar = ActiveSupport::Duration::Scalar.new(10)
+
+    assert_equal({ days: -1, seconds: 10 }, (scalar - 1.day).parts)
+    assert_equal({ days: 1, seconds: 10 }, (scalar - -1.day).parts)
+  end
+
+  def test_scalar_multiply
+    scalar = ActiveSupport::Duration::Scalar.new(5)
+
+    assert_equal 10, 2 * scalar
+    assert_instance_of ActiveSupport::Duration::Scalar, 2 * scalar
+    assert_equal 10, scalar * 2
+    assert_instance_of ActiveSupport::Duration::Scalar, scalar * 2
+    assert_equal 10, 2.seconds * scalar
+    assert_instance_of ActiveSupport::Duration, 2.seconds * scalar
+    assert_equal 10, scalar * 2.seconds
+    assert_instance_of ActiveSupport::Duration, scalar * 2.seconds
+
+    exception = assert_raises(TypeError) do
+      scalar * "foo"
+    end
+
+    assert_equal "no implicit conversion of String into ActiveSupport::Duration::Scalar", exception.message
+  end
+
+  def test_scalar_multiply_parts
+    scalar = ActiveSupport::Duration::Scalar.new(1)
+    assert_equal({ days: 2 }, (scalar * 2.days).parts)
+    assert_equal(172800, (scalar * 2.days).value)
+    assert_equal({ days: -2 }, (scalar * -2.days).parts)
+    assert_equal(-172800, (scalar * -2.days).value)
+  end
+
+  def test_scalar_divide
+    scalar = ActiveSupport::Duration::Scalar.new(10)
+
+    assert_equal 10, 100 / scalar
+    assert_instance_of ActiveSupport::Duration::Scalar, 100 / scalar
+    assert_equal 5, scalar / 2
+    assert_instance_of ActiveSupport::Duration::Scalar, scalar / 2
+    assert_equal 10, 100.seconds / scalar
+    assert_instance_of ActiveSupport::Duration, 100.seconds / scalar
+    assert_equal 5, scalar / 2.seconds
+    assert_kind_of Integer, scalar / 2.seconds
+
+    exception = assert_raises(TypeError) do
+      scalar / "foo"
+    end
+
+    assert_equal "no implicit conversion of String into ActiveSupport::Duration::Scalar", exception.message
+  end
+
+  def test_scalar_modulo
+    scalar = ActiveSupport::Duration::Scalar.new(10)
+
+    assert_equal 1, 31 % scalar
+    assert_instance_of ActiveSupport::Duration::Scalar, 31 % scalar
+    assert_equal 1, scalar % 3
+    assert_instance_of ActiveSupport::Duration::Scalar, scalar % 3
+    assert_equal 1, 31.seconds % scalar
+    assert_instance_of ActiveSupport::Duration, 31.seconds % scalar
+    assert_equal 1, scalar % 3.seconds
+    assert_instance_of ActiveSupport::Duration, scalar % 3.seconds
+
+    exception = assert_raises(TypeError) do
+      scalar % "foo"
+    end
+
+    assert_equal "no implicit conversion of String into ActiveSupport::Duration::Scalar", exception.message
+  end
+
+  def test_scalar_modulo_parts
+    scalar = ActiveSupport::Duration::Scalar.new(82800)
+    assert_equal({ hours: 1 }, (scalar % 2.hours).parts)
+    assert_equal(3600, (scalar % 2.hours).value)
+  end
+
+  def test_twelve_months_equals_one_year
+    assert_equal 12.months, 1.year
+  end
+
+  def test_thirty_days_does_not_equal_one_month
+    assert_not_equal 30.days, 1.month
+  end
+
+  def test_adding_one_month_maintains_day_of_month
+    (1..11).each do |month|
+      [1, 14, 28].each do |day|
+        assert_equal Date.civil(2016, month + 1, day), Date.civil(2016, month, day) + 1.month
+      end
+    end
+
+    assert_equal Date.civil(2017, 1, 1),  Date.civil(2016, 12, 1) + 1.month
+    assert_equal Date.civil(2017, 1, 14),  Date.civil(2016, 12, 14) + 1.month
+    assert_equal Date.civil(2017, 1, 28),  Date.civil(2016, 12, 28) + 1.month
+
+    assert_equal Date.civil(2015, 2, 28), Date.civil(2015, 1, 31) + 1.month
+    assert_equal Date.civil(2016, 2, 29), Date.civil(2016, 1, 31) + 1.month
+  end
+
   # ISO8601 string examples are taken from ISO8601 gem at https://github.com/arnau/ISO8601/blob/b93d466840/spec/iso8601/duration_spec.rb
   # published under the conditions of MIT license at https://github.com/arnau/ISO8601/blob/b93d466840/LICENSE
   #
@@ -260,7 +535,7 @@ class DurationTest < ActiveSupport::TestCase
   # WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 
   def test_iso8601_parsing_wrong_patterns_with_raise
-    invalid_patterns = ['', 'P', 'PT', 'P1YT', 'T', 'PW', 'P1Y1W', '~P1Y', '.P1Y', 'P1.5Y0.5M', 'P1.5Y1M', 'P1.5MT10.5S']
+    invalid_patterns = ["", "P", "PT", "P1YT", "T", "PW", "P1Y1W", "~P1Y", ".P1Y", "P1.5Y0.5M", "P1.5Y1M", "P1.5MT10.5S"]
     invalid_patterns.each do |pattern|
       assert_raise ActiveSupport::Duration::ISO8601Parser::ParsingError, pattern.inspect do
         ActiveSupport::Duration.parse(pattern)
@@ -270,15 +545,16 @@ class DurationTest < ActiveSupport::TestCase
 
   def test_iso8601_output
     expectations = [
-      ['P1Y',           1.year                           ],
-      ['P1W',           1.week                           ],
-      ['P1Y1M',         1.year + 1.month                 ],
-      ['P1Y1M1D',       1.year + 1.month + 1.day         ],
-      ['-P1Y1D',        -1.year - 1.day                  ],
-      ['P1Y-1DT-1S',    1.year - 1.day - 1.second        ], # Parts with different signs are exists in PostgreSQL interval datatype.
-      ['PT1S',          1.second                         ],
-      ['PT1.4S',        (1.4).seconds                    ],
-      ['P1Y1M1DT1H',    1.year + 1.month + 1.day + 1.hour],
+      ["P1Y",           1.year                           ],
+      ["P1W",           1.week                           ],
+      ["P1Y1M",         1.year + 1.month                 ],
+      ["P1Y1M1D",       1.year + 1.month + 1.day         ],
+      ["-P1Y1D",        -1.year - 1.day                  ],
+      ["P1Y-1DT-1S",    1.year - 1.day - 1.second        ], # Parts with different signs are exists in PostgreSQL interval datatype.
+      ["PT1S",          1.second                         ],
+      ["PT1.4S",        (1.4).seconds                    ],
+      ["P1Y1M1DT1H",    1.year + 1.month + 1.day + 1.hour],
+      ["PT0S",          0.minutes                        ],
     ]
     expectations.each do |expected_output, duration|
       assert_equal expected_output, duration.iso8601, expected_output.inspect
@@ -287,17 +563,17 @@ class DurationTest < ActiveSupport::TestCase
 
   def test_iso8601_output_precision
     expectations = [
-        [nil, 'P1Y1MT5.55S',  1.year + 1.month + (5.55).seconds ],
-        [0,   'P1Y1MT6S',     1.year + 1.month + (5.55).seconds ],
-        [1,   'P1Y1MT5.5S',   1.year + 1.month + (5.55).seconds ],
-        [2,   'P1Y1MT5.55S',  1.year + 1.month + (5.55).seconds ],
-        [3,   'P1Y1MT5.550S', 1.year + 1.month + (5.55).seconds ],
-        [nil, 'PT1S',         1.second                          ],
-        [2,   'PT1.00S',      1.second                          ],
-        [nil, 'PT1.4S',       (1.4).seconds                     ],
-        [0,   'PT1S',         (1.4).seconds                     ],
-        [1,   'PT1.4S',       (1.4).seconds                     ],
-        [5,   'PT1.40000S',   (1.4).seconds                     ],
+        [nil, "P1Y1MT8.55S",  1.year + 1.month + (8.55).seconds ],
+        [0,   "P1Y1MT9S",     1.year + 1.month + (8.55).seconds ],
+        [1,   "P1Y1MT8.6S",   1.year + 1.month + (8.55).seconds ],
+        [2,   "P1Y1MT8.55S",  1.year + 1.month + (8.55).seconds ],
+        [3,   "P1Y1MT8.550S", 1.year + 1.month + (8.55).seconds ],
+        [nil, "PT1S",         1.second                          ],
+        [2,   "PT1.00S",      1.second                          ],
+        [nil, "PT1.4S",       (1.4).seconds                     ],
+        [0,   "PT1S",         (1.4).seconds                     ],
+        [1,   "PT1.4S",       (1.4).seconds                     ],
+        [5,   "PT1.40000S",   (1.4).seconds                     ],
     ]
     expectations.each do |precision, expected_output, duration|
       assert_equal expected_output, duration.iso8601(precision: precision), expected_output.inspect
@@ -314,7 +590,64 @@ class DurationTest < ActiveSupport::TestCase
     time = Time.current
     patterns.each do |pattern|
       duration = ActiveSupport::Duration.parse(pattern)
-      assert_equal time+duration, time+ActiveSupport::Duration.parse(duration.iso8601), pattern.inspect
+      assert_equal time + duration, time + ActiveSupport::Duration.parse(duration.iso8601), pattern.inspect
+    end
+  end
+
+  def test_iso8601_parsing_across_spring_dst_boundary
+    with_env_tz eastern_time_zone do
+      with_tz_default "Eastern Time (US & Canada)" do
+        travel_to Time.utc(2016, 3, 11) do
+          assert_equal 604800, ActiveSupport::Duration.parse("P7D").to_i
+          assert_equal 604800, ActiveSupport::Duration.parse("P1W").to_i
+        end
+      end
     end
   end
+
+  def test_iso8601_parsing_across_autumn_dst_boundary
+    with_env_tz eastern_time_zone do
+      with_tz_default "Eastern Time (US & Canada)" do
+        travel_to Time.utc(2016, 11, 4) do
+          assert_equal 604800, ActiveSupport::Duration.parse("P7D").to_i
+          assert_equal 604800, ActiveSupport::Duration.parse("P1W").to_i
+        end
+      end
+    end
+  end
+
+  def test_iso8601_parsing_equivalence_with_numeric_extensions_over_long_periods
+    with_env_tz eastern_time_zone do
+      with_tz_default "Eastern Time (US & Canada)" do
+        assert_equal 3.months, ActiveSupport::Duration.parse("P3M")
+        assert_equal 3.months.to_i, ActiveSupport::Duration.parse("P3M").to_i
+        assert_equal 10.months, ActiveSupport::Duration.parse("P10M")
+        assert_equal 10.months.to_i, ActiveSupport::Duration.parse("P10M").to_i
+        assert_equal 3.years, ActiveSupport::Duration.parse("P3Y")
+        assert_equal 3.years.to_i, ActiveSupport::Duration.parse("P3Y").to_i
+        assert_equal 10.years, ActiveSupport::Duration.parse("P10Y")
+        assert_equal 10.years.to_i, ActiveSupport::Duration.parse("P10Y").to_i
+      end
+    end
+  end
+
+  def test_adding_durations_do_not_hold_prior_states
+    time = Time.parse("Nov 29, 2016")
+    # If the implementation adds and subtracts 3 months, the
+    # resulting date would have been in February so the day will
+    # change to the 29th.
+    d1 = 3.months - 3.months
+    d2 = 2.months - 2.months
+
+    assert_equal time + d1, time + d2
+  end
+
+  private
+    def eastern_time_zone
+      if Gem.win_platform?
+        "EST5EDT"
+      else
+        "America/New_York"
+      end
+    end
 end
diff --git a/activesupport/test/core_ext/enumerable_test.rb b/activesupport/test/core_ext/enumerable_test.rb
index 99c3236c35..8d71320931 100644
--- a/activesupport/test/core_ext/enumerable_test.rb
+++ b/activesupport/test/core_ext/enumerable_test.rb
@@ -1,6 +1,8 @@
-require 'abstract_unit'
-require 'active_support/core_ext/array'
-require 'active_support/core_ext/enumerable'
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "active_support/core_ext/array"
+require "active_support/core_ext/enumerable"
 
 Payment = Struct.new(:price)
 ExpandedPayment = Struct.new(:dollars, :cents)
@@ -22,7 +24,7 @@ class EnumerableTests < ActiveSupport::TestCase
     end
   end
 
-  def assert_typed_equal(e, v, cls, msg=nil)
+  def assert_typed_equal(e, v, cls, msg = nil)
     assert_kind_of(cls, v, msg)
     assert_equal(e, v, msg)
   end
@@ -33,8 +35,8 @@ class EnumerableTests < ActiveSupport::TestCase
     assert_equal 60, enum.sum { |i| i * 2 }
 
     enum = GenericEnumerable.new(%w(a b c))
-    assert_equal 'abc', enum.sum
-    assert_equal 'aabbcc', enum.sum { |i| i * 2 }
+    assert_equal "abc", enum.sum
+    assert_equal "aabbcc", enum.sum { |i| i * 2 }
 
     payments = GenericEnumerable.new([ Payment.new(5), Payment.new(15), Payment.new(10) ])
     assert_equal 30, payments.sum(&:price)
@@ -70,12 +72,12 @@ class EnumerableTests < ActiveSupport::TestCase
     sum = GenericEnumerable.new([1.quo(2), 1.quo(3)]).sum
     assert_typed_equal(5.quo(6), sum, Rational)
 
-    sum = GenericEnumerable.new([2.0, 3.0*Complex::I]).sum
+    sum = GenericEnumerable.new([2.0, 3.0 * Complex::I]).sum
     assert_typed_equal(Complex(2.0, 3.0), sum, Complex)
     assert_typed_equal(2.0, sum.real, Float)
     assert_typed_equal(3.0, sum.imag, Float)
 
-    sum = GenericEnumerable.new([1, 2]).sum(10) {|v| v * 2 }
+    sum = GenericEnumerable.new([1, 2]).sum(10) { |v| v * 2 }
     assert_typed_equal(16, sum, Integer)
   end
 
@@ -102,7 +104,7 @@ class EnumerableTests < ActiveSupport::TestCase
     assert_equal 10, (1..4).sum
     assert_equal 10, (1..4.5).sum
     assert_equal 6, (1...4).sum
-    assert_equal 'abc', ('a'..'c').sum
+    assert_equal "abc", ("a".."c").sum
     assert_equal 50_000_005_000_000, (0..10_000_000).sum
     assert_equal 0, (10..0).sum
     assert_equal 5, (10..0).sum(5)
@@ -120,8 +122,8 @@ class EnumerableTests < ActiveSupport::TestCase
     assert_equal 60, enum.sum { |i| i * 2 }
 
     enum = %w(a b c)
-    assert_equal 'abc', enum.sum
-    assert_equal 'aabbcc', enum.sum { |i| i * 2 }
+    assert_equal "abc", enum.sum
+    assert_equal "aabbcc", enum.sum { |i| i * 2 }
 
     payments = [ Payment.new(5), Payment.new(15), Payment.new(10) ]
     assert_equal 30, payments.sum(&:price)
@@ -157,12 +159,12 @@ class EnumerableTests < ActiveSupport::TestCase
     sum = [1.quo(2), 1.quo(3)].sum
     assert_typed_equal(5.quo(6), sum, Rational)
 
-    sum = [2.0, 3.0*Complex::I].sum
+    sum = [2.0, 3.0 * Complex::I].sum
     assert_typed_equal(Complex(2.0, 3.0), sum, Complex)
     assert_typed_equal(2.0, sum.real, Float)
     assert_typed_equal(3.0, sum.imag, Float)
 
-    sum = [1, 2].sum(10) {|v| v * 2 }
+    sum = [1, 2].sum(10) { |v| v * 2 }
     assert_typed_equal(16, sum, Integer)
   end
 
@@ -171,30 +173,28 @@ class EnumerableTests < ActiveSupport::TestCase
     assert_equal({ 5 => Payment.new(5), 15 => Payment.new(15), 10 => Payment.new(10) },
                  payments.index_by(&:price))
     assert_equal Enumerator, payments.index_by.class
-    if Enumerator.method_defined? :size
-      assert_equal nil, payments.index_by.size
-      assert_equal 42, (1..42).index_by.size
-    end
+    assert_nil payments.index_by.size
+    assert_equal 42, (1..42).index_by.size
     assert_equal({ 5 => Payment.new(5), 15 => Payment.new(15), 10 => Payment.new(10) },
                  payments.index_by.each(&:price))
   end
 
   def test_many
-    assert_equal false, GenericEnumerable.new([]         ).many?
-    assert_equal false, GenericEnumerable.new([ 1 ]      ).many?
-    assert_equal true,  GenericEnumerable.new([ 1, 2 ]   ).many?
-
-    assert_equal false, GenericEnumerable.new([]         ).many? {|x| x > 1 }
-    assert_equal false, GenericEnumerable.new([ 2 ]      ).many? {|x| x > 1 }
-    assert_equal false, GenericEnumerable.new([ 1, 2 ]   ).many? {|x| x > 1 }
-    assert_equal true,  GenericEnumerable.new([ 1, 2, 2 ]).many? {|x| x > 1 }
+    assert_equal false, GenericEnumerable.new([]).many?
+    assert_equal false, GenericEnumerable.new([ 1 ]).many?
+    assert_equal true,  GenericEnumerable.new([ 1, 2 ]).many?
+
+    assert_equal false, GenericEnumerable.new([]).many? { |x| x > 1 }
+    assert_equal false, GenericEnumerable.new([ 2 ]).many? { |x| x > 1 }
+    assert_equal false, GenericEnumerable.new([ 1, 2 ]).many? { |x| x > 1 }
+    assert_equal true,  GenericEnumerable.new([ 1, 2, 2 ]).many? { |x| x > 1 }
   end
 
   def test_many_iterates_only_on_what_is_needed
-    infinity = 1.0/0.0
+    infinity = 1.0 / 0.0
     very_long_enum = 0..infinity
     assert_equal true, very_long_enum.many?
-    assert_equal true, very_long_enum.many?{|x| x > 100}
+    assert_equal true, very_long_enum.many? { |x| x > 100 }
   end
 
   def test_exclude?
@@ -206,7 +206,7 @@ class EnumerableTests < ActiveSupport::TestCase
     assert_equal [1, 2, 4], GenericEnumerable.new((1..5).to_a).without(3, 5)
     assert_equal [1, 2, 4], (1..5).to_a.without(3, 5)
     assert_equal [1, 2, 4], (1..5).to_set.without(3, 5)
-    assert_equal({foo: 1, baz: 3}, {foo: 1, bar: 2, baz: 3}.without(:bar))
+    assert_equal({ foo: 1, baz: 3 }, { foo: 1, bar: 2, baz: 3 }.without(:bar))
   end
 
   def test_pluck
diff --git a/activesupport/test/core_ext/file_test.rb b/activesupport/test/core_ext/file_test.rb
index cde0132b97..23e3c277cc 100644
--- a/activesupport/test/core_ext/file_test.rb
+++ b/activesupport/test/core_ext/file_test.rb
@@ -1,5 +1,7 @@
-require 'abstract_unit'
-require 'active_support/core_ext/file'
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "active_support/core_ext/file"
 
 class AtomicWriteTest < ActiveSupport::TestCase
   def test_atomic_write_without_errors
diff --git a/activesupport/test/core_ext/hash/transform_keys_test.rb b/activesupport/test/core_ext/hash/transform_keys_test.rb
index 962d3a30b6..b9e41f7b25 100644
--- a/activesupport/test/core_ext/hash/transform_keys_test.rb
+++ b/activesupport/test/core_ext/hash/transform_keys_test.rb
@@ -1,62 +1,64 @@
-require 'abstract_unit'
-require 'active_support/core_ext/hash/keys'
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "active_support/core_ext/hash/keys"
 
 class TransformKeysTest < ActiveSupport::TestCase
   test "transform_keys returns a new hash with the keys computed from the block" do
-    original = { a: 'a', b: 'b' }
+    original = { a: "a", b: "b" }
     mapped = original.transform_keys { |k| "#{k}!".to_sym }
 
-    assert_equal({ a: 'a', b: 'b' }, original)
-    assert_equal({ a!: 'a', b!: 'b' }, mapped)
+    assert_equal({ a: "a", b: "b" }, original)
+    assert_equal({ a!: "a", b!: "b" }, mapped)
   end
 
   test "transform_keys! modifies the keys of the original" do
-    original = { a: 'a', b: 'b' }
+    original = { a: "a", b: "b" }
     mapped = original.transform_keys! { |k| "#{k}!".to_sym }
 
-    assert_equal({ a!: 'a', b!: 'b' }, original)
+    assert_equal({ a!: "a", b!: "b" }, original)
     assert_same original, mapped
   end
 
   test "transform_keys returns a sized Enumerator if no block is given" do
-    original = { a: 'a', b: 'b' }
+    original = { a: "a", b: "b" }
     enumerator = original.transform_keys
     assert_equal original.size, enumerator.size
     assert_equal Enumerator, enumerator.class
   end
 
   test "transform_keys! returns a sized Enumerator if no block is given" do
-    original = { a: 'a', b: 'b' }
+    original = { a: "a", b: "b" }
     enumerator = original.transform_keys!
     assert_equal original.size, enumerator.size
     assert_equal Enumerator, enumerator.class
   end
 
   test "transform_keys is chainable with Enumerable methods" do
-    original = { a: 'a', b: 'b' }
+    original = { a: "a", b: "b" }
     mapped = original.transform_keys.with_index { |k, i| [k, i].join.to_sym }
-    assert_equal({ a0: 'a', b1: 'b' }, mapped)
+    assert_equal({ a0: "a", b1: "b" }, mapped)
   end
 
   test "transform_keys! is chainable with Enumerable methods" do
-    original = { a: 'a', b: 'b' }
+    original = { a: "a", b: "b" }
     original.transform_keys!.with_index { |k, i| [k, i].join.to_sym }
-    assert_equal({ a0: 'a', b1: 'b' }, original)
+    assert_equal({ a0: "a", b1: "b" }, original)
   end
 
   test "transform_keys returns a Hash instance when self is inherited from Hash" do
     class HashDescendant < ::Hash
       def initialize(elements = nil)
         super(elements)
-        (elements || {}).each_pair{ |key, value| self[key] = value }
+        (elements || {}).each_pair { |key, value| self[key] = value }
       end
     end
 
-    original = HashDescendant.new({ a: 'a', b: 'b' })
+    original = HashDescendant.new(a: "a", b: "b")
     mapped = original.transform_keys { |k| "#{k}!".to_sym }
 
-    assert_equal({ a: 'a', b: 'b' }, original)
-    assert_equal({ a!: 'a', b!: 'b' }, mapped)
+    assert_equal({ a: "a", b: "b" }, original)
+    assert_equal({ a!: "a", b!: "b" }, mapped)
     assert_equal(::Hash, mapped.class)
   end
 end
diff --git a/activesupport/test/core_ext/hash/transform_values_test.rb b/activesupport/test/core_ext/hash/transform_values_test.rb
index 114022fbaf..d34b7fa7b9 100644
--- a/activesupport/test/core_ext/hash/transform_values_test.rb
+++ b/activesupport/test/core_ext/hash/transform_values_test.rb
@@ -1,75 +1,77 @@
-require 'abstract_unit'
-require 'active_support/core_ext/hash/indifferent_access'
-require 'active_support/core_ext/hash/transform_values'
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "active_support/core_ext/hash/indifferent_access"
+require "active_support/core_ext/hash/transform_values"
 
 class TransformValuesTest < ActiveSupport::TestCase
   test "transform_values returns a new hash with the values computed from the block" do
-    original = { a: 'a', b: 'b' }
-    mapped = original.transform_values { |v| v + '!' }
+    original = { a: "a", b: "b" }
+    mapped = original.transform_values { |v| v + "!" }
 
-    assert_equal({ a: 'a', b: 'b' }, original)
-    assert_equal({ a: 'a!', b: 'b!' }, mapped)
+    assert_equal({ a: "a", b: "b" }, original)
+    assert_equal({ a: "a!", b: "b!" }, mapped)
   end
 
   test "transform_values! modifies the values of the original" do
-    original = { a: 'a', b: 'b' }
-    mapped = original.transform_values! { |v| v + '!' }
+    original = { a: "a", b: "b" }
+    mapped = original.transform_values! { |v| v + "!" }
 
-    assert_equal({ a: 'a!', b: 'b!' }, original)
+    assert_equal({ a: "a!", b: "b!" }, original)
     assert_same original, mapped
   end
 
   test "indifferent access is still indifferent after mapping values" do
-    original = { a: 'a', b: 'b' }.with_indifferent_access
-    mapped = original.transform_values { |v| v + '!' }
+    original = { a: "a", b: "b" }.with_indifferent_access
+    mapped = original.transform_values { |v| v + "!" }
 
-    assert_equal 'a!', mapped[:a]
-    assert_equal 'a!', mapped['a']
+    assert_equal "a!", mapped[:a]
+    assert_equal "a!", mapped["a"]
   end
 
   # This is to be consistent with the behavior of Ruby's built in methods
   # (e.g. #select, #reject) as of 2.2
   test "default values do not persist during mapping" do
-    original = Hash.new('foo')
-    original[:a] = 'a'
-    mapped = original.transform_values { |v| v + '!' }
+    original = Hash.new("foo")
+    original[:a] = "a"
+    mapped = original.transform_values { |v| v + "!" }
 
-    assert_equal 'a!', mapped[:a]
+    assert_equal "a!", mapped[:a]
     assert_nil mapped[:b]
   end
 
   test "default procs do not persist after mapping" do
-    original = Hash.new { 'foo' }
-    original[:a] = 'a'
-    mapped = original.transform_values { |v| v + '!' }
+    original = Hash.new { "foo" }
+    original[:a] = "a"
+    mapped = original.transform_values { |v| v + "!" }
 
-    assert_equal 'a!', mapped[:a]
+    assert_equal "a!", mapped[:a]
     assert_nil mapped[:b]
   end
 
   test "transform_values returns a sized Enumerator if no block is given" do
-    original = { a: 'a', b: 'b' }
+    original = { a: "a", b: "b" }
     enumerator = original.transform_values
     assert_equal original.size, enumerator.size
     assert_equal Enumerator, enumerator.class
   end
 
   test "transform_values! returns a sized Enumerator if no block is given" do
-    original = { a: 'a', b: 'b' }
+    original = { a: "a", b: "b" }
     enumerator = original.transform_values!
     assert_equal original.size, enumerator.size
     assert_equal Enumerator, enumerator.class
   end
 
   test "transform_values is chainable with Enumerable methods" do
-    original = { a: 'a', b: 'b' }
+    original = { a: "a", b: "b" }
     mapped = original.transform_values.with_index { |v, i| [v, i].join }
-    assert_equal({ a: 'a0', b: 'b1' }, mapped)
+    assert_equal({ a: "a0", b: "b1" }, mapped)
   end
 
   test "transform_values! is chainable with Enumerable methods" do
-    original = { a: 'a', b: 'b' }
+    original = { a: "a", b: "b" }
     original.transform_values!.with_index { |v, i| [v, i].join }
-    assert_equal({ a: 'a0', b: 'b1' }, original)
+    assert_equal({ a: "a0", b: "b1" }, original)
   end
 end
diff --git a/activesupport/test/core_ext/hash_ext_test.rb b/activesupport/test/core_ext/hash_ext_test.rb
index e8099baa35..17952e9fc7 100644
--- a/activesupport/test/core_ext/hash_ext_test.rb
+++ b/activesupport/test/core_ext/hash_ext_test.rb
@@ -1,55 +1,32 @@
-require 'abstract_unit'
-require 'active_support/core_ext/hash'
-require 'bigdecimal'
-require 'active_support/core_ext/string/access'
-require 'active_support/ordered_hash'
-require 'active_support/core_ext/object/conversions'
-require 'active_support/core_ext/object/deep_dup'
-require 'active_support/inflections'
+# frozen_string_literal: true
 
-class HashExtTest < ActiveSupport::TestCase
-  class IndifferentHash < ActiveSupport::HashWithIndifferentAccess
-  end
-
-  class SubclassingArray < Array
-  end
-
-  class SubclassingHash < Hash
-  end
-
-  class NonIndifferentHash < Hash
-    def nested_under_indifferent_access
-      self
-    end
-  end
-
-  class HashByConversion
-    def initialize(hash)
-      @hash = hash
-    end
-
-    def to_hash
-      @hash
-    end
-  end
+require "abstract_unit"
+require "active_support/core_ext/hash"
+require "bigdecimal"
+require "active_support/core_ext/string/access"
+require "active_support/ordered_hash"
+require "active_support/core_ext/object/conversions"
+require "active_support/core_ext/object/deep_dup"
+require "active_support/inflections"
 
+class HashExtTest < ActiveSupport::TestCase
   def setup
-    @strings = { 'a' => 1, 'b' => 2 }
-    @nested_strings = { 'a' => { 'b' => { 'c' => 3 } } }
-    @symbols = { :a => 1, :b => 2 }
-    @nested_symbols = { :a => { :b => { :c => 3 } } }
-    @mixed = { :a => 1, 'b' => 2 }
-    @nested_mixed = { 'a' => { :b => { 'c' => 3 } } }
+    @strings = { "a" => 1, "b" => 2 }
+    @nested_strings = { "a" => { "b" => { "c" => 3 } } }
+    @symbols = { a: 1, b: 2 }
+    @nested_symbols = { a: { b: { c: 3 } } }
+    @mixed = { :a => 1, "b" => 2 }
+    @nested_mixed = { "a" => { b: { "c" => 3 } } }
     @integers = { 0 => 1, 1 => 2 }
-    @nested_integers = { 0 => { 1 => { 2 => 3} } }
+    @nested_integers = { 0 => { 1 => { 2 => 3 } } }
     @illegal_symbols = { [] => 3 }
-    @nested_illegal_symbols = { [] => { [] => 3} }
-    @upcase_strings = { 'A' => 1, 'B' => 2 }
-    @nested_upcase_strings = { 'A' => { 'B' => { 'C' => 3 } } }
-    @string_array_of_hashes = { 'a' => [ { 'b' => 2 }, { 'c' => 3 }, 4 ] }
-    @symbol_array_of_hashes = { :a => [ { :b => 2 }, { :c => 3 }, 4 ] }
-    @mixed_array_of_hashes = { :a => [ { :b => 2 }, { 'c' => 3 }, 4 ] }
-    @upcase_array_of_hashes = { 'A' => [ { 'B' => 2 }, { 'C' => 3 }, 4 ] }
+    @nested_illegal_symbols = { [] => { [] => 3 } }
+    @upcase_strings = { "A" => 1, "B" => 2 }
+    @nested_upcase_strings = { "A" => { "B" => { "C" => 3 } } }
+    @string_array_of_hashes = { "a" => [ { "b" => 2 }, { "c" => 3 }, 4 ] }
+    @symbol_array_of_hashes = { a: [ { b: 2 }, { c: 3 }, 4 ] }
+    @mixed_array_of_hashes = { a: [ { b: 2 }, { "c" => 3 }, 4 ] }
+    @upcase_array_of_hashes = { "A" => [ { "B" => 2 }, { "C" => 3 }, 4 ] }
   end
 
   def test_methods
@@ -75,59 +52,59 @@ class HashExtTest < ActiveSupport::TestCase
   end
 
   def test_transform_keys
-    assert_equal @upcase_strings, @strings.transform_keys{ |key| key.to_s.upcase }
-    assert_equal @upcase_strings, @symbols.transform_keys{ |key| key.to_s.upcase }
-    assert_equal @upcase_strings, @mixed.transform_keys{ |key| key.to_s.upcase }
+    assert_equal @upcase_strings, @strings.transform_keys { |key| key.to_s.upcase }
+    assert_equal @upcase_strings, @symbols.transform_keys { |key| key.to_s.upcase }
+    assert_equal @upcase_strings, @mixed.transform_keys { |key| key.to_s.upcase }
   end
 
   def test_transform_keys_not_mutates
     transformed_hash = @mixed.dup
-    transformed_hash.transform_keys{ |key| key.to_s.upcase }
+    transformed_hash.transform_keys { |key| key.to_s.upcase }
     assert_equal @mixed, transformed_hash
   end
 
   def test_deep_transform_keys
-    assert_equal @nested_upcase_strings, @nested_symbols.deep_transform_keys{ |key| key.to_s.upcase }
-    assert_equal @nested_upcase_strings, @nested_strings.deep_transform_keys{ |key| key.to_s.upcase }
-    assert_equal @nested_upcase_strings, @nested_mixed.deep_transform_keys{ |key| key.to_s.upcase }
-    assert_equal @upcase_array_of_hashes, @string_array_of_hashes.deep_transform_keys{ |key| key.to_s.upcase }
-    assert_equal @upcase_array_of_hashes, @symbol_array_of_hashes.deep_transform_keys{ |key| key.to_s.upcase }
-    assert_equal @upcase_array_of_hashes, @mixed_array_of_hashes.deep_transform_keys{ |key| key.to_s.upcase }
+    assert_equal @nested_upcase_strings, @nested_symbols.deep_transform_keys { |key| key.to_s.upcase }
+    assert_equal @nested_upcase_strings, @nested_strings.deep_transform_keys { |key| key.to_s.upcase }
+    assert_equal @nested_upcase_strings, @nested_mixed.deep_transform_keys { |key| key.to_s.upcase }
+    assert_equal @upcase_array_of_hashes, @string_array_of_hashes.deep_transform_keys { |key| key.to_s.upcase }
+    assert_equal @upcase_array_of_hashes, @symbol_array_of_hashes.deep_transform_keys { |key| key.to_s.upcase }
+    assert_equal @upcase_array_of_hashes, @mixed_array_of_hashes.deep_transform_keys { |key| key.to_s.upcase }
   end
 
   def test_deep_transform_keys_not_mutates
     transformed_hash = @nested_mixed.deep_dup
-    transformed_hash.deep_transform_keys{ |key| key.to_s.upcase }
+    transformed_hash.deep_transform_keys { |key| key.to_s.upcase }
     assert_equal @nested_mixed, transformed_hash
   end
 
   def test_transform_keys!
-    assert_equal @upcase_strings, @symbols.dup.transform_keys!{ |key| key.to_s.upcase }
-    assert_equal @upcase_strings, @strings.dup.transform_keys!{ |key| key.to_s.upcase }
-    assert_equal @upcase_strings, @mixed.dup.transform_keys!{ |key| key.to_s.upcase }
+    assert_equal @upcase_strings, @symbols.dup.transform_keys! { |key| key.to_s.upcase }
+    assert_equal @upcase_strings, @strings.dup.transform_keys! { |key| key.to_s.upcase }
+    assert_equal @upcase_strings, @mixed.dup.transform_keys! { |key| key.to_s.upcase }
   end
 
   def test_transform_keys_with_bang_mutates
     transformed_hash = @mixed.dup
-    transformed_hash.transform_keys!{ |key| key.to_s.upcase }
+    transformed_hash.transform_keys! { |key| key.to_s.upcase }
     assert_equal @upcase_strings, transformed_hash
-    assert_equal @mixed, { :a => 1, "b" => 2 }
+    assert_equal({ :a => 1, "b" => 2 }, @mixed)
   end
 
   def test_deep_transform_keys!
-    assert_equal @nested_upcase_strings, @nested_symbols.deep_dup.deep_transform_keys!{ |key| key.to_s.upcase }
-    assert_equal @nested_upcase_strings, @nested_strings.deep_dup.deep_transform_keys!{ |key| key.to_s.upcase }
-    assert_equal @nested_upcase_strings, @nested_mixed.deep_dup.deep_transform_keys!{ |key| key.to_s.upcase }
-    assert_equal @upcase_array_of_hashes, @string_array_of_hashes.deep_dup.deep_transform_keys!{ |key| key.to_s.upcase }
-    assert_equal @upcase_array_of_hashes, @symbol_array_of_hashes.deep_dup.deep_transform_keys!{ |key| key.to_s.upcase }
-    assert_equal @upcase_array_of_hashes, @mixed_array_of_hashes.deep_dup.deep_transform_keys!{ |key| key.to_s.upcase }
+    assert_equal @nested_upcase_strings, @nested_symbols.deep_dup.deep_transform_keys! { |key| key.to_s.upcase }
+    assert_equal @nested_upcase_strings, @nested_strings.deep_dup.deep_transform_keys! { |key| key.to_s.upcase }
+    assert_equal @nested_upcase_strings, @nested_mixed.deep_dup.deep_transform_keys! { |key| key.to_s.upcase }
+    assert_equal @upcase_array_of_hashes, @string_array_of_hashes.deep_dup.deep_transform_keys! { |key| key.to_s.upcase }
+    assert_equal @upcase_array_of_hashes, @symbol_array_of_hashes.deep_dup.deep_transform_keys! { |key| key.to_s.upcase }
+    assert_equal @upcase_array_of_hashes, @mixed_array_of_hashes.deep_dup.deep_transform_keys! { |key| key.to_s.upcase }
   end
 
   def test_deep_transform_keys_with_bang_mutates
     transformed_hash = @nested_mixed.deep_dup
-    transformed_hash.deep_transform_keys!{ |key| key.to_s.upcase }
+    transformed_hash.deep_transform_keys! { |key| key.to_s.upcase }
     assert_equal @nested_upcase_strings, transformed_hash
-    assert_equal @nested_mixed, { 'a' => { :b => { 'c' => 3 } } }
+    assert_equal({ "a" => { b: { "c" => 3 } } }, @nested_mixed)
   end
 
   def test_symbolize_keys
@@ -167,7 +144,7 @@ class HashExtTest < ActiveSupport::TestCase
     transformed_hash = @mixed.dup
     transformed_hash.deep_symbolize_keys!
     assert_equal @symbols, transformed_hash
-    assert_equal @mixed, { :a => 1, "b" => 2 }
+    assert_equal({ :a => 1, "b" => 2 }, @mixed)
   end
 
   def test_deep_symbolize_keys!
@@ -183,7 +160,7 @@ class HashExtTest < ActiveSupport::TestCase
     transformed_hash = @nested_mixed.deep_dup
     transformed_hash.deep_symbolize_keys!
     assert_equal @nested_symbols, transformed_hash
-    assert_equal @nested_mixed, { 'a' => { :b => { 'c' => 3 } } }
+    assert_equal({ "a" => { b: { "c" => 3 } } }, @nested_mixed)
   end
 
   def test_symbolize_keys_preserves_keys_that_cant_be_symbolized
@@ -243,7 +220,7 @@ class HashExtTest < ActiveSupport::TestCase
     transformed_hash = @mixed.dup
     transformed_hash.stringify_keys!
     assert_equal @strings, transformed_hash
-    assert_equal @mixed, { :a => 1, "b" => 2 }
+    assert_equal({ :a => 1, "b" => 2 }, @mixed)
   end
 
   def test_deep_stringify_keys!
@@ -259,497 +236,45 @@ class HashExtTest < ActiveSupport::TestCase
     transformed_hash = @nested_mixed.deep_dup
     transformed_hash.deep_stringify_keys!
     assert_equal @nested_strings, transformed_hash
-    assert_equal @nested_mixed, { 'a' => { :b => { 'c' => 3 } } }
-  end
-
-  def test_symbolize_keys_for_hash_with_indifferent_access
-    assert_instance_of Hash, @symbols.with_indifferent_access.symbolize_keys
-    assert_equal @symbols, @symbols.with_indifferent_access.symbolize_keys
-    assert_equal @symbols, @strings.with_indifferent_access.symbolize_keys
-    assert_equal @symbols, @mixed.with_indifferent_access.symbolize_keys
-  end
-
-  def test_deep_symbolize_keys_for_hash_with_indifferent_access
-    assert_instance_of Hash, @nested_symbols.with_indifferent_access.deep_symbolize_keys
-    assert_equal @nested_symbols, @nested_symbols.with_indifferent_access.deep_symbolize_keys
-    assert_equal @nested_symbols, @nested_strings.with_indifferent_access.deep_symbolize_keys
-    assert_equal @nested_symbols, @nested_mixed.with_indifferent_access.deep_symbolize_keys
-  end
-
-
-  def test_symbolize_keys_bang_for_hash_with_indifferent_access
-    assert_raise(NoMethodError) { @symbols.with_indifferent_access.dup.symbolize_keys! }
-    assert_raise(NoMethodError) { @strings.with_indifferent_access.dup.symbolize_keys! }
-    assert_raise(NoMethodError) { @mixed.with_indifferent_access.dup.symbolize_keys! }
-  end
-
-  def test_deep_symbolize_keys_bang_for_hash_with_indifferent_access
-    assert_raise(NoMethodError) { @nested_symbols.with_indifferent_access.deep_dup.deep_symbolize_keys! }
-    assert_raise(NoMethodError) { @nested_strings.with_indifferent_access.deep_dup.deep_symbolize_keys! }
-    assert_raise(NoMethodError) { @nested_mixed.with_indifferent_access.deep_dup.deep_symbolize_keys! }
-  end
-
-  def test_symbolize_keys_preserves_keys_that_cant_be_symbolized_for_hash_with_indifferent_access
-    assert_equal @illegal_symbols, @illegal_symbols.with_indifferent_access.symbolize_keys
-    assert_raise(NoMethodError) { @illegal_symbols.with_indifferent_access.dup.symbolize_keys! }
-  end
-
-  def test_deep_symbolize_keys_preserves_keys_that_cant_be_symbolized_for_hash_with_indifferent_access
-    assert_equal @nested_illegal_symbols, @nested_illegal_symbols.with_indifferent_access.deep_symbolize_keys
-    assert_raise(NoMethodError) { @nested_illegal_symbols.with_indifferent_access.deep_dup.deep_symbolize_keys! }
-  end
-
-  def test_symbolize_keys_preserves_integer_keys_for_hash_with_indifferent_access
-    assert_equal @integers, @integers.with_indifferent_access.symbolize_keys
-    assert_raise(NoMethodError) { @integers.with_indifferent_access.dup.symbolize_keys! }
-  end
-
-  def test_deep_symbolize_keys_preserves_integer_keys_for_hash_with_indifferent_access
-    assert_equal @nested_integers, @nested_integers.with_indifferent_access.deep_symbolize_keys
-    assert_raise(NoMethodError) { @nested_integers.with_indifferent_access.deep_dup.deep_symbolize_keys! }
-  end
-
-  def test_stringify_keys_for_hash_with_indifferent_access
-    assert_instance_of ActiveSupport::HashWithIndifferentAccess, @symbols.with_indifferent_access.stringify_keys
-    assert_equal @strings, @symbols.with_indifferent_access.stringify_keys
-    assert_equal @strings, @strings.with_indifferent_access.stringify_keys
-    assert_equal @strings, @mixed.with_indifferent_access.stringify_keys
-  end
-
-  def test_deep_stringify_keys_for_hash_with_indifferent_access
-    assert_instance_of ActiveSupport::HashWithIndifferentAccess, @nested_symbols.with_indifferent_access.deep_stringify_keys
-    assert_equal @nested_strings, @nested_symbols.with_indifferent_access.deep_stringify_keys
-    assert_equal @nested_strings, @nested_strings.with_indifferent_access.deep_stringify_keys
-    assert_equal @nested_strings, @nested_mixed.with_indifferent_access.deep_stringify_keys
-  end
-
-  def test_stringify_keys_bang_for_hash_with_indifferent_access
-    assert_instance_of ActiveSupport::HashWithIndifferentAccess, @symbols.with_indifferent_access.dup.stringify_keys!
-    assert_equal @strings, @symbols.with_indifferent_access.dup.stringify_keys!
-    assert_equal @strings, @strings.with_indifferent_access.dup.stringify_keys!
-    assert_equal @strings, @mixed.with_indifferent_access.dup.stringify_keys!
-  end
-
-  def test_deep_stringify_keys_bang_for_hash_with_indifferent_access
-    assert_instance_of ActiveSupport::HashWithIndifferentAccess, @nested_symbols.with_indifferent_access.dup.deep_stringify_keys!
-    assert_equal @nested_strings, @nested_symbols.with_indifferent_access.deep_dup.deep_stringify_keys!
-    assert_equal @nested_strings, @nested_strings.with_indifferent_access.deep_dup.deep_stringify_keys!
-    assert_equal @nested_strings, @nested_mixed.with_indifferent_access.deep_dup.deep_stringify_keys!
-  end
-
-  def test_nested_under_indifferent_access
-    foo = { "foo" => SubclassingHash.new.tap { |h| h["bar"] = "baz" } }.with_indifferent_access
-    assert_kind_of ActiveSupport::HashWithIndifferentAccess, foo["foo"]
-
-    foo = { "foo" => NonIndifferentHash.new.tap { |h| h["bar"] = "baz" } }.with_indifferent_access
-    assert_kind_of NonIndifferentHash, foo["foo"]
-
-    foo = { "foo" => IndifferentHash.new.tap { |h| h["bar"] = "baz" } }.with_indifferent_access
-    assert_kind_of IndifferentHash, foo["foo"]
-  end
-
-  def test_indifferent_assorted
-    @strings = @strings.with_indifferent_access
-    @symbols = @symbols.with_indifferent_access
-    @mixed   = @mixed.with_indifferent_access
-
-    assert_equal 'a', @strings.__send__(:convert_key, :a)
-
-    assert_equal 1, @strings.fetch('a')
-    assert_equal 1, @strings.fetch(:a.to_s)
-    assert_equal 1, @strings.fetch(:a)
-
-    hashes = { :@strings => @strings, :@symbols => @symbols, :@mixed => @mixed }
-    method_map = { :'[]' => 1, :fetch => 1, :values_at => [1],
-      :has_key? => true, :include? => true, :key? => true,
-      :member? => true }
-
-    hashes.each do |name, hash|
-      method_map.sort_by(&:to_s).each do |meth, expected|
-        assert_equal(expected, hash.__send__(meth, 'a'),
-                     "Calling #{name}.#{meth} 'a'")
-        assert_equal(expected, hash.__send__(meth, :a),
-                     "Calling #{name}.#{meth} :a")
-      end
-    end
-
-    assert_equal [1, 2], @strings.values_at('a', 'b')
-    assert_equal [1, 2], @strings.values_at(:a, :b)
-    assert_equal [1, 2], @symbols.values_at('a', 'b')
-    assert_equal [1, 2], @symbols.values_at(:a, :b)
-    assert_equal [1, 2], @mixed.values_at('a', 'b')
-    assert_equal [1, 2], @mixed.values_at(:a, :b)
-  end
-
-  def test_indifferent_reading
-    hash = HashWithIndifferentAccess.new
-    hash["a"] = 1
-    hash["b"] = true
-    hash["c"] = false
-    hash["d"] = nil
-
-    assert_equal 1, hash[:a]
-    assert_equal true, hash[:b]
-    assert_equal false, hash[:c]
-    assert_equal nil, hash[:d]
-    assert_equal nil, hash[:e]
-  end
-
-  def test_indifferent_reading_with_nonnil_default
-    hash = HashWithIndifferentAccess.new(1)
-    hash["a"] = 1
-    hash["b"] = true
-    hash["c"] = false
-    hash["d"] = nil
-
-    assert_equal 1, hash[:a]
-    assert_equal true, hash[:b]
-    assert_equal false, hash[:c]
-    assert_equal nil, hash[:d]
-    assert_equal 1, hash[:e]
-  end
-
-  def test_indifferent_writing
-    hash = HashWithIndifferentAccess.new
-    hash[:a] = 1
-    hash['b'] = 2
-    hash[3] = 3
-
-    assert_equal hash['a'], 1
-    assert_equal hash['b'], 2
-    assert_equal hash[:a], 1
-    assert_equal hash[:b], 2
-    assert_equal hash[3], 3
-  end
-
-  def test_indifferent_update
-    hash = HashWithIndifferentAccess.new
-    hash[:a] = 'a'
-    hash['b'] = 'b'
-
-    updated_with_strings = hash.update(@strings)
-    updated_with_symbols = hash.update(@symbols)
-    updated_with_mixed = hash.update(@mixed)
-
-    assert_equal updated_with_strings[:a], 1
-    assert_equal updated_with_strings['a'], 1
-    assert_equal updated_with_strings['b'], 2
-
-    assert_equal updated_with_symbols[:a], 1
-    assert_equal updated_with_symbols['b'], 2
-    assert_equal updated_with_symbols[:b], 2
-
-    assert_equal updated_with_mixed[:a], 1
-    assert_equal updated_with_mixed['b'], 2
-
-    assert [updated_with_strings, updated_with_symbols, updated_with_mixed].all? { |h| h.keys.size == 2 }
-  end
-
-  def test_update_with_to_hash_conversion
-    hash = HashWithIndifferentAccess.new
-    hash.update HashByConversion.new({ :a => 1 })
-    assert_equal hash['a'], 1
-  end
-
-  def test_indifferent_merging
-    hash = HashWithIndifferentAccess.new
-    hash[:a] = 'failure'
-    hash['b'] = 'failure'
-
-    other = { 'a' => 1, :b => 2 }
-
-    merged = hash.merge(other)
-
-    assert_equal HashWithIndifferentAccess, merged.class
-    assert_equal 1, merged[:a]
-    assert_equal 2, merged['b']
-
-    hash.update(other)
-
-    assert_equal 1, hash[:a]
-    assert_equal 2, hash['b']
-  end
-
-  def test_merge_with_to_hash_conversion
-    hash = HashWithIndifferentAccess.new
-    merged = hash.merge HashByConversion.new({ :a => 1 })
-    assert_equal merged['a'], 1
-  end
-
-  def test_indifferent_replace
-    hash = HashWithIndifferentAccess.new
-    hash[:a] = 42
-
-    replaced = hash.replace(b: 12)
-
-    assert hash.key?('b')
-    assert !hash.key?(:a)
-    assert_equal 12, hash[:b]
-    assert_same hash, replaced
-  end
-
-  def test_replace_with_to_hash_conversion
-    hash = HashWithIndifferentAccess.new
-    hash[:a] = 42
-
-    replaced = hash.replace(HashByConversion.new(b: 12))
-
-    assert hash.key?('b')
-    assert !hash.key?(:a)
-    assert_equal 12, hash[:b]
-    assert_same hash, replaced
-  end
-
-  def test_indifferent_merging_with_block
-    hash = HashWithIndifferentAccess.new
-    hash[:a] = 1
-    hash['b'] = 3
-
-    other = { 'a' => 4, :b => 2, 'c' => 10 }
-
-    merged = hash.merge(other) { |key, old, new| old > new ? old : new }
-
-    assert_equal HashWithIndifferentAccess, merged.class
-    assert_equal 4, merged[:a]
-    assert_equal 3, merged['b']
-    assert_equal 10, merged[:c]
-
-    other_indifferent = HashWithIndifferentAccess.new('a' => 9, :b => 2)
-
-    merged = hash.merge(other_indifferent) { |key, old, new| old + new }
-
-    assert_equal HashWithIndifferentAccess, merged.class
-    assert_equal 10, merged[:a]
-    assert_equal 5, merged[:b]
-  end
-
-  def test_indifferent_reverse_merging
-    hash = HashWithIndifferentAccess.new key: :old_value
-    hash.reverse_merge! key: :new_value
-    assert_equal :old_value, hash[:key]
-
-    hash = HashWithIndifferentAccess.new('some' => 'value', 'other' => 'value')
-    hash.reverse_merge!(:some => 'noclobber', :another => 'clobber')
-    assert_equal 'value', hash[:some]
-    assert_equal 'clobber', hash[:another]
-  end
-
-  def test_indifferent_deleting
-    get_hash = proc{ { :a => 'foo' }.with_indifferent_access }
-    hash = get_hash.call
-    assert_equal hash.delete(:a), 'foo'
-    assert_equal hash.delete(:a), nil
-    hash = get_hash.call
-    assert_equal hash.delete('a'), 'foo'
-    assert_equal hash.delete('a'), nil
-  end
-
-  def test_indifferent_select
-    hash = ActiveSupport::HashWithIndifferentAccess.new(@strings).select {|k,v| v == 1}
-
-    assert_equal({ 'a' => 1 }, hash)
-    assert_instance_of ActiveSupport::HashWithIndifferentAccess, hash
-  end
-
-  def test_indifferent_select_returns_enumerator
-    enum = ActiveSupport::HashWithIndifferentAccess.new(@strings).select
-    assert_instance_of Enumerator, enum
-  end
-
-  def test_indifferent_select_returns_a_hash_when_unchanged
-    hash = ActiveSupport::HashWithIndifferentAccess.new(@strings).select {|k,v| true}
-
-    assert_instance_of ActiveSupport::HashWithIndifferentAccess, hash
-  end
-
-  def test_indifferent_select_bang
-    indifferent_strings = ActiveSupport::HashWithIndifferentAccess.new(@strings)
-    indifferent_strings.select! {|k,v| v == 1}
-
-    assert_equal({ 'a' => 1 }, indifferent_strings)
-    assert_instance_of ActiveSupport::HashWithIndifferentAccess, indifferent_strings
-  end
-
-  def test_indifferent_reject
-    hash = ActiveSupport::HashWithIndifferentAccess.new(@strings).reject {|k,v| v != 1}
-
-    assert_equal({ 'a' => 1 }, hash)
-    assert_instance_of ActiveSupport::HashWithIndifferentAccess, hash
-  end
-
-  def test_indifferent_reject_returns_enumerator
-    enum = ActiveSupport::HashWithIndifferentAccess.new(@strings).reject
-    assert_instance_of Enumerator, enum
-  end
-
-  def test_indifferent_reject_bang
-    indifferent_strings = ActiveSupport::HashWithIndifferentAccess.new(@strings)
-    indifferent_strings.reject! {|k,v| v != 1}
-
-    assert_equal({ 'a' => 1 }, indifferent_strings)
-    assert_instance_of ActiveSupport::HashWithIndifferentAccess, indifferent_strings
-  end
-
-  def test_indifferent_to_hash
-    # Should convert to a Hash with String keys.
-    assert_equal @strings, @mixed.with_indifferent_access.to_hash
-
-    # Should preserve the default value.
-    mixed_with_default = @mixed.dup
-    mixed_with_default.default = '1234'
-    roundtrip = mixed_with_default.with_indifferent_access.to_hash
-    assert_equal @strings, roundtrip
-    assert_equal '1234', roundtrip.default
-
-    # Ensure nested hashes are not HashWithIndiffereneAccess
-    new_to_hash = @nested_mixed.with_indifferent_access.to_hash
-    assert_not new_to_hash.instance_of?(HashWithIndifferentAccess)
-    assert_not new_to_hash["a"].instance_of?(HashWithIndifferentAccess)
-    assert_not new_to_hash["a"]["b"].instance_of?(HashWithIndifferentAccess)
-  end
-
-  def test_lookup_returns_the_same_object_that_is_stored_in_hash_indifferent_access
-    hash = HashWithIndifferentAccess.new {|h, k| h[k] = []}
-    hash[:a] << 1
-
-    assert_equal [1], hash[:a]
-  end
-
-  def test_with_indifferent_access_has_no_side_effects_on_existing_hash
-    hash = {content: [{:foo => :bar, 'bar' => 'baz'}]}
-    hash.with_indifferent_access
-
-    assert_equal [:foo, "bar"], hash[:content].first.keys
-  end
-
-  def test_indifferent_hash_with_array_of_hashes
-    hash = { "urls" => { "url" => [ { "address" => "1" }, { "address" => "2" } ] }}.with_indifferent_access
-    assert_equal "1", hash[:urls][:url].first[:address]
-
-    hash = hash.to_hash
-    assert_not hash.instance_of?(HashWithIndifferentAccess)
-    assert_not hash["urls"].instance_of?(HashWithIndifferentAccess)
-    assert_not hash["urls"]["url"].first.instance_of?(HashWithIndifferentAccess)
-  end
-
-  def test_should_preserve_array_subclass_when_value_is_array
-    array = SubclassingArray.new
-    array << { "address" => "1" }
-    hash = { "urls" => { "url" => array }}.with_indifferent_access
-    assert_equal SubclassingArray, hash[:urls][:url].class
-  end
-
-  def test_should_preserve_array_class_when_hash_value_is_frozen_array
-    array = SubclassingArray.new
-    array << { "address" => "1" }
-    hash = { "urls" => { "url" => array.freeze }}.with_indifferent_access
-    assert_equal SubclassingArray, hash[:urls][:url].class
-  end
-
-  def test_stringify_and_symbolize_keys_on_indifferent_preserves_hash
-    h = HashWithIndifferentAccess.new
-    h[:first] = 1
-    h = h.stringify_keys
-    assert_equal 1, h['first']
-    h = HashWithIndifferentAccess.new
-    h['first'] = 1
-    h = h.symbolize_keys
-    assert_equal 1, h[:first]
-  end
-
-  def test_deep_stringify_and_deep_symbolize_keys_on_indifferent_preserves_hash
-    h = HashWithIndifferentAccess.new
-    h[:first] = 1
-    h = h.deep_stringify_keys
-    assert_equal 1, h['first']
-    h = HashWithIndifferentAccess.new
-    h['first'] = 1
-    h = h.deep_symbolize_keys
-    assert_equal 1, h[:first]
-  end
-
-  def test_to_options_on_indifferent_preserves_hash
-    h = HashWithIndifferentAccess.new
-    h['first'] = 1
-    h.to_options!
-    assert_equal 1, h['first']
-  end
-
-  def test_to_options_on_indifferent_preserves_works_as_hash_with_dup
-    h = HashWithIndifferentAccess.new({ a: { b: 'b' } })
-    dup = h.dup
-
-    dup[:a][:c] = 'c'
-    assert_equal 'c', h[:a][:c]
-  end
-
-  def test_indifferent_sub_hashes
-    h = {'user' => {'id' => 5}}.with_indifferent_access
-    ['user', :user].each {|user| [:id, 'id'].each {|id| assert_equal 5, h[user][id], "h[#{user.inspect}][#{id.inspect}] should be 5"}}
-
-    h = {:user => {:id => 5}}.with_indifferent_access
-    ['user', :user].each {|user| [:id, 'id'].each {|id| assert_equal 5, h[user][id], "h[#{user.inspect}][#{id.inspect}] should be 5"}}
-  end
-
-  def test_indifferent_duplication
-    # Should preserve default value
-    h = HashWithIndifferentAccess.new
-    h.default = '1234'
-    assert_equal h.default, h.dup.default
-
-    # Should preserve class for subclasses
-    h = IndifferentHash.new
-    assert_equal h.class, h.dup.class
-  end
-
-  def test_nested_dig_indifferent_access
-    skip if RUBY_VERSION < "2.3.0"
-    data = {"this" => {"views" => 1234}}.with_indifferent_access
-    assert_equal 1234, data.dig(:this, :views)
+    assert_equal({ "a" => { b: { "c" => 3 } } }, @nested_mixed)
   end
 
   def test_assert_valid_keys
     assert_nothing_raised do
-      { :failure => "stuff", :funny => "business" }.assert_valid_keys([ :failure, :funny ])
-      { :failure => "stuff", :funny => "business" }.assert_valid_keys(:failure, :funny)
+      { failure: "stuff", funny: "business" }.assert_valid_keys([ :failure, :funny ])
+      { failure: "stuff", funny: "business" }.assert_valid_keys(:failure, :funny)
     end
     # not all valid keys are required to be present
     assert_nothing_raised do
-      { :failure => "stuff", :funny => "business" }.assert_valid_keys([ :failure, :funny, :sunny ])
-      { :failure => "stuff", :funny => "business" }.assert_valid_keys(:failure, :funny, :sunny)
+      { failure: "stuff", funny: "business" }.assert_valid_keys([ :failure, :funny, :sunny ])
+      { failure: "stuff", funny: "business" }.assert_valid_keys(:failure, :funny, :sunny)
     end
 
     exception = assert_raise ArgumentError do
-      { :failore => "stuff", :funny => "business" }.assert_valid_keys([ :failure, :funny ])
+      { failore: "stuff", funny: "business" }.assert_valid_keys([ :failure, :funny ])
     end
     assert_equal "Unknown key: :failore. Valid keys are: :failure, :funny", exception.message
 
     exception = assert_raise ArgumentError do
-      { :failore => "stuff", :funny => "business" }.assert_valid_keys(:failure, :funny)
+      { failore: "stuff", funny: "business" }.assert_valid_keys(:failure, :funny)
     end
     assert_equal "Unknown key: :failore. Valid keys are: :failure, :funny", exception.message
 
     exception = assert_raise ArgumentError do
-      { :failore => "stuff", :funny => "business" }.assert_valid_keys([ :failure ])
+      { failore: "stuff", funny: "business" }.assert_valid_keys([ :failure ])
     end
     assert_equal "Unknown key: :failore. Valid keys are: :failure", exception.message
 
     exception = assert_raise ArgumentError do
-      { :failore => "stuff", :funny => "business" }.assert_valid_keys(:failure)
+      { failore: "stuff", funny: "business" }.assert_valid_keys(:failure)
     end
     assert_equal "Unknown key: :failore. Valid keys are: :failure", exception.message
   end
 
-  def test_assorted_keys_not_stringified
-    original = {Object.new => 2, 1 => 2, [] => true}
-    indiff = original.with_indifferent_access
-    assert(!indiff.keys.any? {|k| k.kind_of? String}, "A key was converted to a string!")
-  end
-
   def test_deep_merge
-    hash_1 = { :a => "a", :b => "b", :c => { :c1 => "c1", :c2 => "c2", :c3 => { :d1 => "d1" } } }
-    hash_2 = { :a => 1, :c => { :c1 => 2, :c3 => { :d2 => "d2" } } }
-    expected = { :a => 1, :b => "b", :c => { :c1 => 2, :c2 => "c2", :c3 => { :d1 => "d1", :d2 => "d2" } } }
+    hash_1 = { a: "a", b: "b", c: { c1: "c1", c2: "c2", c3: { d1: "d1" } } }
+    hash_2 = { a: 1, c: { c1: 2, c3: { d2: "d2" } } }
+    expected = { a: 1, b: "b", c: { c1: 2, c2: "c2", c3: { d1: "d1", d2: "d2" } } }
     assert_equal expected, hash_1.deep_merge(hash_2)
 
     hash_1.deep_merge!(hash_2)
@@ -757,60 +282,29 @@ class HashExtTest < ActiveSupport::TestCase
   end
 
   def test_deep_merge_with_block
-    hash_1 = { :a => "a", :b => "b", :c => { :c1 => "c1", :c2 => "c2", :c3 => { :d1 => "d1" } } }
-    hash_2 = { :a => 1, :c => { :c1 => 2, :c3 => { :d2 => "d2" } } }
-    expected = { :a => [:a, "a", 1], :b => "b", :c => { :c1 => [:c1, "c1", 2], :c2 => "c2", :c3 => { :d1 => "d1", :d2 => "d2" } } }
-    assert_equal(expected, hash_1.deep_merge(hash_2) { |k,o,n| [k, o, n] })
+    hash_1 = { a: "a", b: "b", c: { c1: "c1", c2: "c2", c3: { d1: "d1" } } }
+    hash_2 = { a: 1, c: { c1: 2, c3: { d2: "d2" } } }
+    expected = { a: [:a, "a", 1], b: "b", c: { c1: [:c1, "c1", 2], c2: "c2", c3: { d1: "d1", d2: "d2" } } }
+    assert_equal(expected, hash_1.deep_merge(hash_2) { |k, o, n| [k, o, n] })
 
-    hash_1.deep_merge!(hash_2) { |k,o,n| [k, o, n] }
+    hash_1.deep_merge!(hash_2) { |k, o, n| [k, o, n] }
     assert_equal expected, hash_1
   end
 
   def test_deep_merge_with_falsey_values
     hash_1 = { e: false }
-    hash_2 = { e: 'e' }
-    expected = { e: [:e, false, 'e'] }
+    hash_2 = { e: "e" }
+    expected = { e: [:e, false, "e"] }
     assert_equal(expected, hash_1.deep_merge(hash_2) { |k, o, n| [k, o, n] })
 
     hash_1.deep_merge!(hash_2) { |k, o, n| [k, o, n] }
     assert_equal expected, hash_1
   end
 
-  def test_deep_merge_on_indifferent_access
-    hash_1 = HashWithIndifferentAccess.new({ :a => "a", :b => "b", :c => { :c1 => "c1", :c2 => "c2", :c3 => { :d1 => "d1" } } })
-    hash_2 = HashWithIndifferentAccess.new({ :a => 1, :c => { :c1 => 2, :c3 => { :d2 => "d2" } } })
-    hash_3 = { :a => 1, :c => { :c1 => 2, :c3 => { :d2 => "d2" } } }
-    expected = { "a" => 1, "b" => "b", "c" => { "c1" => 2, "c2" => "c2", "c3" => { "d1" => "d1", "d2" => "d2" } } }
-    assert_equal expected, hash_1.deep_merge(hash_2)
-    assert_equal expected, hash_1.deep_merge(hash_3)
-
-    hash_1.deep_merge!(hash_2)
-    assert_equal expected, hash_1
-  end
-
-  def test_store_on_indifferent_access
-    hash = HashWithIndifferentAccess.new
-    hash.store(:test1, 1)
-    hash.store('test1', 11)
-    hash[:test2] = 2
-    hash['test2'] = 22
-    expected = { "test1" => 11, "test2" => 22 }
-    assert_equal expected, hash
-  end
-
-  def test_constructor_on_indifferent_access
-    hash = HashWithIndifferentAccess[:foo, 1]
-    assert_equal 1, hash[:foo]
-    assert_equal 1, hash['foo']
-    hash[:foo] = 3
-    assert_equal 3, hash[:foo]
-    assert_equal 3, hash['foo']
-  end
-
   def test_reverse_merge
-    defaults = { :a => "x", :b => "y", :c => 10 }.freeze
-    options  = { :a => 1, :b => 2 }
-    expected = { :a => 1, :b => 2, :c => 10 }
+    defaults = { d: 0, a: "x", b: "y", c: 10 }.freeze
+    options  = { a: 1, b: 2 }
+    expected = { d: 0, a: 1, b: 2, c: 10 }
 
     # Should merge defaults into options, creating a new hash.
     assert_equal expected, options.reverse_merge(defaults)
@@ -821,15 +315,33 @@ class HashExtTest < ActiveSupport::TestCase
     assert_equal expected, merged.reverse_merge!(defaults)
     assert_equal expected, merged
 
+    # Make the order consistent with the non-overwriting reverse merge.
+    assert_equal expected.keys, merged.keys
+
     # Should be an alias for reverse_merge!
     merged = options.dup
     assert_equal expected, merged.reverse_update(defaults)
     assert_equal expected, merged
   end
 
+  def test_with_defaults_aliases_reverse_merge
+    defaults = { a: "x", b: "y", c: 10 }.freeze
+    options  = { a: 1, b: 2 }
+    expected = { a: 1, b: 2, c: 10 }
+
+    # Should be an alias for reverse_merge
+    assert_equal expected, options.with_defaults(defaults)
+    assert_not_equal expected, options
+
+    # Should be an alias for reverse_merge!
+    merged = options.dup
+    assert_equal expected, merged.with_defaults!(defaults)
+    assert_equal expected, merged
+  end
+
   def test_slice
-    original = { :a => 'x', :b => 'y', :c => 10 }
-    expected = { :a => 'x', :b => 'y' }
+    original = { a: "x", b: "y", c: 10 }
+    expected = { a: "x", b: "y" }
 
     # Should return a new hash with only the given keys.
     assert_equal expected, original.slice(:a, :b)
@@ -837,15 +349,15 @@ class HashExtTest < ActiveSupport::TestCase
   end
 
   def test_slice_inplace
-    original = { :a => 'x', :b => 'y', :c => 10 }
-    expected = { :c => 10 }
+    original = { a: "x", b: "y", c: 10 }
+    expected = { c: 10 }
 
     # Should replace the hash with only the given keys.
     assert_equal expected, original.slice!(:a, :b)
   end
 
   def test_slice_with_an_array_key
-    original = { :a => 'x', :b => 'y', :c => 10, [:a, :b] => "an array key" }
+    original = { :a => "x", :b => "y", :c => 10, [:a, :b] => "an array key" }
     expected = { [:a, :b] => "an array key", :c => 10 }
 
     # Should return a new hash with only the given keys when given an array key.
@@ -854,53 +366,21 @@ class HashExtTest < ActiveSupport::TestCase
   end
 
   def test_slice_inplace_with_an_array_key
-    original = { :a => 'x', :b => 'y', :c => 10, [:a, :b] => "an array key" }
-    expected = { :a => 'x', :b => 'y' }
+    original = { :a => "x", :b => "y", :c => 10, [:a, :b] => "an array key" }
+    expected = { a: "x", b: "y" }
 
     # Should replace the hash with only the given keys when given an array key.
     assert_equal expected, original.slice!([:a, :b], :c)
   end
 
   def test_slice_with_splatted_keys
-    original = { :a => 'x', :b => 'y', :c => 10, [:a, :b] => "an array key" }
-    expected = { :a => 'x', :b => "y" }
+    original = { :a => "x", :b => "y", :c => 10, [:a, :b] => "an array key" }
+    expected = { a: "x", b: "y" }
 
     # Should grab each of the splatted keys.
     assert_equal expected, original.slice(*[:a, :b])
   end
 
-  def test_indifferent_slice
-    original = { :a => 'x', :b => 'y', :c => 10 }.with_indifferent_access
-    expected = { :a => 'x', :b => 'y' }.with_indifferent_access
-
-    [['a', 'b'], [:a, :b]].each do |keys|
-      # Should return a new hash with only the given keys.
-      assert_equal expected, original.slice(*keys), keys.inspect
-      assert_not_equal expected, original
-    end
-  end
-
-  def test_indifferent_slice_inplace
-    original = { :a => 'x', :b => 'y', :c => 10 }.with_indifferent_access
-    expected = { :c => 10 }.with_indifferent_access
-
-    [['a', 'b'], [:a, :b]].each do |keys|
-      # Should replace the hash with only the given keys.
-      copy = original.dup
-      assert_equal expected, copy.slice!(*keys)
-    end
-  end
-
-  def test_indifferent_slice_access_with_symbols
-    original = {'login' => 'bender', 'password' => 'shiny', 'stuff' => 'foo'}
-    original = original.with_indifferent_access
-
-    slice = original.slice(:login, :password)
-
-    assert_equal 'bender', slice[:login]
-    assert_equal 'bender', slice['login']
-  end
-
   def test_slice_bang_does_not_override_default
     hash = Hash.new(0)
     hash.update(a: 1, b: 2)
@@ -920,39 +400,27 @@ class HashExtTest < ActiveSupport::TestCase
   end
 
   def test_extract
-    original = {:a => 1, :b => 2, :c => 3, :d => 4}
-    expected = {:a => 1, :b => 2}
-    remaining = {:c => 3, :d => 4}
+    original = { a: 1, b: 2, c: 3, d: 4 }
+    expected = { a: 1, b: 2 }
+    remaining = { c: 3, d: 4 }
 
     assert_equal expected, original.extract!(:a, :b, :x)
     assert_equal remaining, original
   end
 
   def test_extract_nils
-    original = {:a => nil, :b => nil}
-    expected = {:a => nil}
+    original = { a: nil, b: nil }
+    expected = { a: nil }
     extracted = original.extract!(:a, :x)
 
     assert_equal expected, extracted
-    assert_equal nil, extracted[:a]
-    assert_equal nil, extracted[:x]
-  end
-
-  def test_indifferent_extract
-    original = {:a => 1, 'b' => 2, :c => 3, 'd' => 4}.with_indifferent_access
-    expected = {:a => 1, :b => 2}.with_indifferent_access
-    remaining = {:c => 3, :d => 4}.with_indifferent_access
-
-    [['a', 'b'], [:a, :b]].each do |keys|
-      copy = original.dup
-      assert_equal expected, copy.extract!(*keys)
-      assert_equal remaining, copy
-    end
+    assert_nil extracted[:a]
+    assert_nil extracted[:x]
   end
 
   def test_except
-    original = { :a => 'x', :b => 'y', :c => 10 }
-    expected = { :a => 'x', :b => 'y' }
+    original = { a: "x", b: "y", c: 10 }
+    expected = { a: "x", b: "y" }
 
     # Should return a new hash without the given keys.
     assert_equal expected, original.except(:c)
@@ -964,8 +432,8 @@ class HashExtTest < ActiveSupport::TestCase
   end
 
   def test_except_with_more_than_one_argument
-    original = { :a => 'x', :b => 'y', :c => 10 }
-    expected = { :a => 'x' }
+    original = { a: "x", b: "y", c: 10 }
+    expected = { a: "x" }
 
     assert_equal expected, original.except(:b, :c)
 
@@ -974,15 +442,15 @@ class HashExtTest < ActiveSupport::TestCase
   end
 
   def test_except_with_original_frozen
-    original = { :a => 'x', :b => 'y' }
+    original = { a: "x", b: "y" }
     original.freeze
     assert_nothing_raised { original.except(:a) }
 
-    assert_raise(RuntimeError) { original.except!(:a) }
+    assert_raise(frozen_error_class) { original.except!(:a) }
   end
 
   def test_except_does_not_delete_values_in_original
-    original = { :a => 'x', :b => 'y' }
+    original = { a: "x", b: "y" }
     assert_not_called(original, :delete) do
       original.except(:a)
     end
@@ -1018,73 +486,18 @@ class HashExtTest < ActiveSupport::TestCase
     assert_equal({}, h)
 
     h = @symbols.dup
-    assert_equal(nil, h.compact!)
+    assert_nil(h.compact!)
     assert_equal(@symbols, h)
   end
-
-  def test_new_with_to_hash_conversion
-    hash = HashWithIndifferentAccess.new(HashByConversion.new(a: 1))
-    assert hash.key?('a')
-    assert_equal 1, hash[:a]
-  end
-
-  def test_dup_with_default_proc
-    hash = HashWithIndifferentAccess.new
-    hash.default_proc = proc { |h, v| raise "walrus" }
-    assert_nothing_raised { hash.dup }
-  end
-
-  def test_dup_with_default_proc_sets_proc
-    hash = HashWithIndifferentAccess.new
-    hash.default_proc = proc { |h, k| k + 1 }
-    new_hash = hash.dup
-
-    assert_equal 3, new_hash[2]
-
-    new_hash.default = 2
-    assert_equal 2, new_hash[:non_existent]
-  end
-
-  def test_to_hash_with_raising_default_proc
-    hash = HashWithIndifferentAccess.new
-    hash.default_proc = proc { |h, k| raise "walrus" }
-
-    assert_nothing_raised { hash.to_hash }
-  end
-
-  def test_new_from_hash_copying_default_should_not_raise_when_default_proc_does
-    hash = Hash.new
-    hash.default_proc = proc { |h, k| raise "walrus" }
-
-    assert_deprecated { HashWithIndifferentAccess.new_from_hash_copying_default(hash) }
-  end
-
-  def test_new_with_to_hash_conversion_copies_default
-    normal_hash = Hash.new(3)
-    normal_hash[:a] = 1
-
-    hash = HashWithIndifferentAccess.new(HashByConversion.new(normal_hash))
-    assert_equal 1, hash[:a]
-    assert_equal 3, hash[:b]
-  end
-
-  def test_new_with_to_hash_conversion_copies_default_proc
-    normal_hash = Hash.new { 1 + 2 }
-    normal_hash[:a] = 1
-
-    hash = HashWithIndifferentAccess.new(HashByConversion.new(normal_hash))
-    assert_equal 1, hash[:a]
-    assert_equal 3, hash[:b]
-  end
 end
 
 class IWriteMyOwnXML
   def to_xml(options = {})
     options[:indent] ||= 2
-    xml = options[:builder] ||= Builder::XmlMarkup.new(:indent => options[:indent])
+    xml = options[:builder] ||= Builder::XmlMarkup.new(indent: options[:indent])
     xml.instruct! unless options[:skip_instruct]
     xml.level_one do
-      xml.tag!(:second_level, 'content')
+      xml.tag!(:second_level, "content")
     end
   end
 end
@@ -1097,139 +510,139 @@ class HashExtToParamTests < ActiveSupport::TestCase
   end
 
   def test_string_hash
-    assert_equal '', {}.to_param
-    assert_equal 'hello=world', { :hello => "world" }.to_param
-    assert_equal 'hello=10', { "hello" => 10 }.to_param
-    assert_equal 'hello=world&say_bye=true', {:hello => "world", "say_bye" => true}.to_param
+    assert_equal "", {}.to_param
+    assert_equal "hello=world", { hello: "world" }.to_param
+    assert_equal "hello=10", { "hello" => 10 }.to_param
+    assert_equal "hello=world&say_bye=true", { :hello => "world", "say_bye" => true }.to_param
   end
 
   def test_number_hash
-    assert_equal '10=20&30=40&50=60', {10 => 20, 30 => 40, 50 => 60}.to_param
+    assert_equal "10=20&30=40&50=60", { 10 => 20, 30 => 40, 50 => 60 }.to_param
   end
 
   def test_to_param_hash
-    assert_equal 'custom-1=param-1&custom2-1=param2-1', {ToParam.new('custom') => ToParam.new('param'), ToParam.new('custom2') => ToParam.new('param2')}.to_param
+    assert_equal "custom-1=param-1&custom2-1=param2-1", { ToParam.new("custom") => ToParam.new("param"), ToParam.new("custom2") => ToParam.new("param2") }.to_param
   end
 
   def test_to_param_hash_escapes_its_keys_and_values
-    assert_equal 'param+1=A+string+with+%2F+characters+%26+that+should+be+%3F+escaped', { 'param 1' => 'A string with / characters & that should be ? escaped' }.to_param
+    assert_equal "param+1=A+string+with+%2F+characters+%26+that+should+be+%3F+escaped", { "param 1" => "A string with / characters & that should be ? escaped" }.to_param
   end
 
   def test_to_param_orders_by_key_in_ascending_order
-    assert_equal 'a=2&b=1&c=0', Hash[*%w(b 1 c 0 a 2)].to_param
+    assert_equal "a=2&b=1&c=0", Hash[*%w(b 1 c 0 a 2)].to_param
   end
 end
 
 class HashToXmlTest < ActiveSupport::TestCase
   def setup
-    @xml_options = { :root => :person, :skip_instruct => true, :indent => 0 }
+    @xml_options = { root: :person, skip_instruct: true, indent: 0 }
   end
 
   def test_one_level
-    xml = { :name => "David", :street => "Paulina" }.to_xml(@xml_options)
+    xml = { name: "David", street: "Paulina" }.to_xml(@xml_options)
     assert_equal "<person>", xml.first(8)
-    assert xml.include?(%(<street>Paulina</street>))
-    assert xml.include?(%(<name>David</name>))
+    assert_includes xml, %(<street>Paulina</street>)
+    assert_includes xml, %(<name>David</name>)
   end
 
   def test_one_level_dasherize_false
-    xml = { :name => "David", :street_name => "Paulina" }.to_xml(@xml_options.merge(:dasherize => false))
+    xml = { name: "David", street_name: "Paulina" }.to_xml(@xml_options.merge(dasherize: false))
     assert_equal "<person>", xml.first(8)
-    assert xml.include?(%(<street_name>Paulina</street_name>))
-    assert xml.include?(%(<name>David</name>))
+    assert_includes xml, %(<street_name>Paulina</street_name>)
+    assert_includes xml, %(<name>David</name>)
   end
 
   def test_one_level_dasherize_true
-    xml = { :name => "David", :street_name => "Paulina" }.to_xml(@xml_options.merge(:dasherize => true))
+    xml = { name: "David", street_name: "Paulina" }.to_xml(@xml_options.merge(dasherize: true))
     assert_equal "<person>", xml.first(8)
-    assert xml.include?(%(<street-name>Paulina</street-name>))
-    assert xml.include?(%(<name>David</name>))
+    assert_includes xml, %(<street-name>Paulina</street-name>)
+    assert_includes xml, %(<name>David</name>)
   end
 
   def test_one_level_camelize_true
-    xml = { :name => "David", :street_name => "Paulina" }.to_xml(@xml_options.merge(:camelize => true))
+    xml = { name: "David", street_name: "Paulina" }.to_xml(@xml_options.merge(camelize: true))
     assert_equal "<Person>", xml.first(8)
-    assert xml.include?(%(<StreetName>Paulina</StreetName>))
-    assert xml.include?(%(<Name>David</Name>))
+    assert_includes xml, %(<StreetName>Paulina</StreetName>)
+    assert_includes xml, %(<Name>David</Name>)
   end
 
   def test_one_level_camelize_lower
-    xml = { :name => "David", :street_name => "Paulina" }.to_xml(@xml_options.merge(:camelize => :lower))
+    xml = { name: "David", street_name: "Paulina" }.to_xml(@xml_options.merge(camelize: :lower))
     assert_equal "<person>", xml.first(8)
-    assert xml.include?(%(<streetName>Paulina</streetName>))
-    assert xml.include?(%(<name>David</name>))
+    assert_includes xml, %(<streetName>Paulina</streetName>)
+    assert_includes xml, %(<name>David</name>)
   end
 
   def test_one_level_with_types
-    xml = { :name => "David", :street => "Paulina", :age => 26, :age_in_millis => 820497600000, :moved_on => Date.new(2005, 11, 15), :resident => :yes }.to_xml(@xml_options)
+    xml = { name: "David", street: "Paulina", age: 26, age_in_millis: 820497600000, moved_on: Date.new(2005, 11, 15), resident: :yes }.to_xml(@xml_options)
     assert_equal "<person>", xml.first(8)
-    assert xml.include?(%(<street>Paulina</street>))
-    assert xml.include?(%(<name>David</name>))
-    assert xml.include?(%(<age type="integer">26</age>))
-    assert xml.include?(%(<age-in-millis type="integer">820497600000</age-in-millis>))
-    assert xml.include?(%(<moved-on type="date">2005-11-15</moved-on>))
-    assert xml.include?(%(<resident type="symbol">yes</resident>))
+    assert_includes xml, %(<street>Paulina</street>)
+    assert_includes xml, %(<name>David</name>)
+    assert_includes xml, %(<age type="integer">26</age>)
+    assert_includes xml, %(<age-in-millis type="integer">820497600000</age-in-millis>)
+    assert_includes xml, %(<moved-on type="date">2005-11-15</moved-on>)
+    assert_includes xml, %(<resident type="symbol">yes</resident>)
   end
 
   def test_one_level_with_nils
-    xml = { :name => "David", :street => "Paulina", :age => nil }.to_xml(@xml_options)
+    xml = { name: "David", street: "Paulina", age: nil }.to_xml(@xml_options)
     assert_equal "<person>", xml.first(8)
-    assert xml.include?(%(<street>Paulina</street>))
-    assert xml.include?(%(<name>David</name>))
-    assert xml.include?(%(<age nil="true"/>))
+    assert_includes xml, %(<street>Paulina</street>)
+    assert_includes xml, %(<name>David</name>)
+    assert_includes xml, %(<age nil="true"/>)
   end
 
   def test_one_level_with_skipping_types
-    xml = { :name => "David", :street => "Paulina", :age => nil }.to_xml(@xml_options.merge(:skip_types => true))
+    xml = { name: "David", street: "Paulina", age: nil }.to_xml(@xml_options.merge(skip_types: true))
     assert_equal "<person>", xml.first(8)
-    assert xml.include?(%(<street>Paulina</street>))
-    assert xml.include?(%(<name>David</name>))
-    assert xml.include?(%(<age nil="true"/>))
+    assert_includes xml, %(<street>Paulina</street>)
+    assert_includes xml, %(<name>David</name>)
+    assert_includes xml, %(<age nil="true"/>)
   end
 
   def test_one_level_with_yielding
-    xml = { :name => "David", :street => "Paulina" }.to_xml(@xml_options) do |x|
+    xml = { name: "David", street: "Paulina" }.to_xml(@xml_options) do |x|
       x.creator("Rails")
     end
 
     assert_equal "<person>", xml.first(8)
-    assert xml.include?(%(<street>Paulina</street>))
-    assert xml.include?(%(<name>David</name>))
-    assert xml.include?(%(<creator>Rails</creator>))
+    assert_includes xml, %(<street>Paulina</street>)
+    assert_includes xml, %(<name>David</name>)
+    assert_includes xml, %(<creator>Rails</creator>)
   end
 
   def test_two_levels
-    xml = { :name => "David", :address => { :street => "Paulina" } }.to_xml(@xml_options)
+    xml = { name: "David", address: { street: "Paulina" } }.to_xml(@xml_options)
     assert_equal "<person>", xml.first(8)
-    assert xml.include?(%(<address><street>Paulina</street></address>))
-    assert xml.include?(%(<name>David</name>))
+    assert_includes xml, %(<address><street>Paulina</street></address>)
+    assert_includes xml, %(<name>David</name>)
   end
 
   def test_two_levels_with_second_level_overriding_to_xml
-    xml = { :name => "David", :address => { :street => "Paulina" }, :child => IWriteMyOwnXML.new }.to_xml(@xml_options)
+    xml = { name: "David", address: { street: "Paulina" }, child: IWriteMyOwnXML.new }.to_xml(@xml_options)
     assert_equal "<person>", xml.first(8)
-    assert xml.include?(%(<address><street>Paulina</street></address>))
-    assert xml.include?(%(<level_one><second_level>content</second_level></level_one>))
+    assert_includes xml, %(<address><street>Paulina</street></address>)
+    assert_includes xml, %(<level_one><second_level>content</second_level></level_one>)
   end
 
   def test_two_levels_with_array
-    xml = { :name => "David", :addresses => [{ :street => "Paulina" }, { :street => "Evergreen" }] }.to_xml(@xml_options)
+    xml = { name: "David", addresses: [{ street: "Paulina" }, { street: "Evergreen" }] }.to_xml(@xml_options)
     assert_equal "<person>", xml.first(8)
-    assert xml.include?(%(<addresses type="array"><address>))
-    assert xml.include?(%(<address><street>Paulina</street></address>))
-    assert xml.include?(%(<address><street>Evergreen</street></address>))
-    assert xml.include?(%(<name>David</name>))
+    assert_includes xml, %(<addresses type="array"><address>)
+    assert_includes xml, %(<address><street>Paulina</street></address>)
+    assert_includes xml, %(<address><street>Evergreen</street></address>)
+    assert_includes xml, %(<name>David</name>)
   end
 
   def test_three_levels_with_array
-    xml = { :name => "David", :addresses => [{ :streets => [ { :name => "Paulina" }, { :name => "Paulina" } ] } ] }.to_xml(@xml_options)
-    assert xml.include?(%(<addresses type="array"><address><streets type="array"><street><name>))
+    xml = { name: "David", addresses: [{ streets: [ { name: "Paulina" }, { name: "Paulina" } ] } ] }.to_xml(@xml_options)
+    assert_includes xml, %(<addresses type="array"><address><streets type="array"><street><name>)
   end
 
   def test_timezoned_attributes
     xml = {
-      :created_at => Time.utc(1999,2,2),
-      :local_created_at => Time.utc(1999,2,2).in_time_zone('Eastern Time (US & Canada)')
+      created_at: Time.utc(1999, 2, 2),
+      local_created_at: Time.utc(1999, 2, 2).in_time_zone("Eastern Time (US & Canada)")
     }.to_xml(@xml_options)
     assert_match %r{<created-at type=\"dateTime\">1999-02-02T00:00:00Z</created-at>}, xml
     assert_match %r{<local-created-at type=\"dateTime\">1999-02-01T19:00:00-05:00</local-created-at>}, xml
@@ -1268,17 +681,17 @@ class HashToXmlTest < ActiveSupport::TestCase
     EOT
 
     expected_topic_hash = {
-      :title => "The First Topic",
-      :author_name => "David",
-      :id => 1,
-      :approved => false,
-      :replies_count => 0,
-      :replies_close_in => 2592000000,
-      :written_on => Date.new(2003, 7, 16),
-      :viewed_at => Time.utc(2003, 7, 16, 9, 28),
-      :content => "Have a nice day",
-      :author_email_address => "david@loudthinking.com",
-      :parent_id => nil
+      title: "The First Topic",
+      author_name: "David",
+      id: 1,
+      approved: false,
+      replies_count: 0,
+      replies_close_in: 2592000000,
+      written_on: Date.new(2003, 7, 16),
+      viewed_at: Time.utc(2003, 7, 16, 9, 28),
+      content: "Have a nice day",
+      author_email_address: "david@loudthinking.com",
+      parent_id: nil
     }.stringify_keys
 
     assert_equal expected_topic_hash, Hash.from_xml(topics_xml)["topics"].first
@@ -1303,18 +716,18 @@ class HashToXmlTest < ActiveSupport::TestCase
     EOT
 
     expected_topic_hash = {
-      :title => "The First Topic",
-      :author_name => "David",
-      :id => 1,
-      :approved => true,
-      :replies_count => 0,
-      :replies_close_in => 2592000000,
-      :written_on => Date.new(2003, 7, 16),
-      :viewed_at => Time.utc(2003, 7, 16, 9, 28),
-      :author_email_address => "david@loudthinking.com",
-      :parent_id => nil,
-      :ad_revenue => BigDecimal("1.50"),
-      :optimum_viewing_angle => 135.0,
+      title: "The First Topic",
+      author_name: "David",
+      id: 1,
+      approved: true,
+      replies_count: 0,
+      replies_close_in: 2592000000,
+      written_on: Date.new(2003, 7, 16),
+      viewed_at: Time.utc(2003, 7, 16, 9, 28),
+      author_email_address: "david@loudthinking.com",
+      parent_id: nil,
+      ad_revenue: BigDecimal("1.50"),
+      optimum_viewing_angle: 135.0,
     }.stringify_keys
 
     assert_equal expected_topic_hash, Hash.from_xml(topic_xml)["topic"]
@@ -1333,12 +746,12 @@ class HashToXmlTest < ActiveSupport::TestCase
     EOT
 
     expected_topic_hash = {
-      :title      => nil,
-      :id         => nil,
-      :approved   => nil,
-      :written_on => nil,
-      :viewed_at  => nil,
-      :parent_id  => nil
+      title: nil,
+      id: nil,
+      approved: nil,
+      written_on: nil,
+      viewed_at: nil,
+      parent_id: nil
     }.stringify_keys
 
     assert_equal expected_topic_hash, Hash.from_xml(topic_xml)["topic"]
@@ -1377,17 +790,17 @@ class HashToXmlTest < ActiveSupport::TestCase
     EOT
 
     expected_topic_hash = {
-      :title => "The First Topic",
-      :author_name => "David",
-      :id => 1,
-      :approved => false,
-      :replies_count => 0,
-      :replies_close_in => 2592000000,
-      :written_on => Date.new(2003, 7, 16),
-      :viewed_at => Time.utc(2003, 7, 16, 9, 28),
-      :content => "Have a nice day",
-      :author_email_address => "david@loudthinking.com",
-      :parent_id => nil
+      title: "The First Topic",
+      author_name: "David",
+      id: 1,
+      approved: false,
+      replies_count: 0,
+      replies_close_in: 2592000000,
+      written_on: Date.new(2003, 7, 16),
+      viewed_at: Time.utc(2003, 7, 16, 9, 28),
+      content: "Have a nice day",
+      author_email_address: "david@loudthinking.com",
+      parent_id: nil
     }.stringify_keys
 
     assert_equal expected_topic_hash, Hash.from_xml(topics_xml)["topics"].first
@@ -1403,14 +816,14 @@ class HashToXmlTest < ActiveSupport::TestCase
     EOT
 
     expected_topic_hash = {
-      :id => "175756086",
-      :owner => "55569174@N00",
-      :secret => "0279bf37a1",
-      :server => "76",
-      :title => "Colored Pencil PhotoBooth Fun",
-      :ispublic => "1",
-      :isfriend => "0",
-      :isfamily => "0",
+      id: "175756086",
+      owner: "55569174@N00",
+      secret: "0279bf37a1",
+      server: "76",
+      title: "Colored Pencil PhotoBooth Fun",
+      ispublic: "1",
+      isfriend: "0",
+      isfamily: "0",
     }.stringify_keys
 
     assert_equal expected_topic_hash, Hash.from_xml(topic_xml)["rsp"]["photos"]["photo"]
@@ -1438,7 +851,7 @@ class HashToXmlTest < ActiveSupport::TestCase
         <posts type="array"></posts>
       </blog>
     XML
-    expected_blog_hash = {"blog" => {"posts" => []}}
+    expected_blog_hash = { "blog" => { "posts" => [] } }
     assert_equal expected_blog_hash, Hash.from_xml(blog_xml)
   end
 
@@ -1449,7 +862,7 @@ class HashToXmlTest < ActiveSupport::TestCase
         </posts>
       </blog>
     XML
-    expected_blog_hash = {"blog" => {"posts" => []}}
+    expected_blog_hash = { "blog" => { "posts" => [] } }
     assert_equal expected_blog_hash, Hash.from_xml(blog_xml)
   end
 
@@ -1461,7 +874,7 @@ class HashToXmlTest < ActiveSupport::TestCase
         </posts>
       </blog>
     XML
-    expected_blog_hash = {"blog" => {"posts" => ["a post"]}}
+    expected_blog_hash = { "blog" => { "posts" => ["a post"] } }
     assert_equal expected_blog_hash, Hash.from_xml(blog_xml)
   end
 
@@ -1474,7 +887,7 @@ class HashToXmlTest < ActiveSupport::TestCase
         </posts>
       </blog>
     XML
-    expected_blog_hash = {"blog" => {"posts" => ["a post", "another post"]}}
+    expected_blog_hash = { "blog" => { "posts" => ["a post", "another post"] } }
     assert_equal expected_blog_hash, Hash.from_xml(blog_xml)
   end
 
@@ -1486,12 +899,12 @@ class HashToXmlTest < ActiveSupport::TestCase
       </blog>
     XML
     hash = Hash.from_xml(blog_xml)
-    assert hash.has_key?('blog')
-    assert hash['blog'].has_key?('logo')
+    assert hash.has_key?("blog")
+    assert hash["blog"].has_key?("logo")
 
-    file = hash['blog']['logo']
-    assert_equal 'logo.png', file.original_filename
-    assert_equal 'image/png', file.content_type
+    file = hash["blog"]["logo"]
+    assert_equal "logo.png", file.original_filename
+    assert_equal "image/png", file.content_type
   end
 
   def test_file_from_xml_with_defaults
@@ -1501,9 +914,9 @@ class HashToXmlTest < ActiveSupport::TestCase
         </logo>
       </blog>
     XML
-    file = Hash.from_xml(blog_xml)['blog']['logo']
-    assert_equal 'untitled', file.original_filename
-    assert_equal 'application/octet-stream', file.content_type
+    file = Hash.from_xml(blog_xml)["blog"]["logo"]
+    assert_equal "untitled", file.original_filename
+    assert_equal "application/octet-stream", file.content_type
   end
 
   def test_tag_with_attrs_and_whitespace
@@ -1512,7 +925,7 @@ class HashToXmlTest < ActiveSupport::TestCase
       </blog>
     XML
     hash = Hash.from_xml(xml)
-    assert_equal "bacon is the best", hash['blog']['name']
+    assert_equal "bacon is the best", hash["blog"]["name"]
   end
 
   def test_empty_cdata_from_xml
@@ -1535,13 +948,13 @@ class HashToXmlTest < ActiveSupport::TestCase
     EOT
 
     expected_bacon_hash = {
-      :weight => 0.5,
-      :chunky => true,
-      :price => BigDecimal("12.50"),
-      :expires_at => Time.utc(2007,12,25,12,34,56),
-      :notes => "",
-      :illustration => "babe.png",
-      :caption => "That'll do, pig."
+      weight: 0.5,
+      chunky: true,
+      price: BigDecimal("12.50"),
+      expires_at: Time.utc(2007, 12, 25, 12, 34, 56),
+      notes: "",
+      illustration: "babe.png",
+      caption: "That'll do, pig."
     }.stringify_keys
 
     assert_equal expected_bacon_hash, Hash.from_xml(bacon_xml)["bacon"]
@@ -1557,8 +970,8 @@ class HashToXmlTest < ActiveSupport::TestCase
     EOT
 
     expected_product_hash = {
-      :weight => 0.5,
-      :image => {'type' => 'ProductImage', 'filename' => 'image.gif' },
+      weight: 0.5,
+      image: { "type" => "ProductImage", "filename" => "image.gif" },
     }.stringify_keys
 
     assert_equal expected_product_hash, Hash.from_xml(product_xml)["product"]
@@ -1581,81 +994,26 @@ class HashToXmlTest < ActiveSupport::TestCase
   end
 
   def test_from_xml_array_one
-    expected = { 'numbers' => { 'type' => 'Array', 'value' => '1' }}
+    expected = { "numbers" => { "type" => "Array", "value" => "1" } }
     assert_equal expected, Hash.from_xml('<numbers type="Array"><value>1</value></numbers>')
   end
 
   def test_from_xml_array_many
-    expected = { 'numbers' => { 'type' => 'Array', 'value' => [ '1', '2' ] }}
+    expected = { "numbers" => { "type" => "Array", "value" => [ "1", "2" ] } }
     assert_equal expected, Hash.from_xml('<numbers type="Array"><value>1</value><value>2</value></numbers>')
   end
 
   def test_from_trusted_xml_allows_symbol_and_yaml_types
-    expected = { 'product' => { 'name' => :value }}
+    expected = { "product" => { "name" => :value } }
     assert_equal expected, Hash.from_trusted_xml('<product><name type="symbol">value</name></product>')
     assert_equal expected, Hash.from_trusted_xml('<product><name type="yaml">:value</name></product>')
   end
 
-  def test_should_use_default_proc_for_unknown_key
-    hash_wia = HashWithIndifferentAccess.new { 1 +  2 }
-    assert_equal 3, hash_wia[:new_key]
-  end
-
-  def test_should_return_nil_if_no_key_is_supplied
-    hash_wia = HashWithIndifferentAccess.new { 1 +  2 }
-    assert_equal nil, hash_wia.default
-  end
-
-  def test_should_use_default_value_for_unknown_key
-    hash_wia = HashWithIndifferentAccess.new(3)
-    assert_equal 3, hash_wia[:new_key]
-  end
-
-  def test_should_use_default_value_if_no_key_is_supplied
-    hash_wia = HashWithIndifferentAccess.new(3)
-    assert_equal 3, hash_wia.default
-  end
-
-  def test_should_nil_if_no_default_value_is_supplied
-    hash_wia = HashWithIndifferentAccess.new
-    assert_nil hash_wia.default
-  end
-
-  def test_should_return_dup_for_with_indifferent_access
-    hash_wia = HashWithIndifferentAccess.new
-    assert_equal hash_wia, hash_wia.with_indifferent_access
-    assert_not_same hash_wia, hash_wia.with_indifferent_access
-  end
-
-  def test_allows_setting_frozen_array_values_with_indifferent_access
-    value = [1, 2, 3].freeze
-    hash = HashWithIndifferentAccess.new
-    hash[:key] = value
-    assert_equal hash[:key], value
-  end
-
-  def test_should_copy_the_default_value_when_converting_to_hash_with_indifferent_access
-    hash = Hash.new(3)
-    hash_wia = hash.with_indifferent_access
-    assert_equal 3, hash_wia.default
-  end
-
-  def test_should_copy_the_default_proc_when_converting_to_hash_with_indifferent_access
-    hash = Hash.new do
-      2 + 1
-    end
-    assert_equal 3, hash[:foo]
-
-    hash_wia = hash.with_indifferent_access
-    assert_equal 3, hash_wia[:foo]
-    assert_equal 3, hash_wia[:bar]
-  end
-
   # The XML builder seems to fail miserably when trying to tag something
   # with the same name as a Kernel method (throw, test, loop, select ...)
   def test_kernel_method_names_to_xml
-    hash     = { :throw => { :ball => 'red' } }
-    expected = '<person><throw><ball>red</ball></throw></person>'
+    hash     = { throw: { ball: "red" } }
+    expected = "<person><throw><ball>red</ball></throw></person>"
 
     assert_nothing_raised do
       assert_equal expected, hash.to_xml(@xml_options)
@@ -1670,30 +1028,30 @@ class HashToXmlTest < ActiveSupport::TestCase
 
   def test_escaping_to_xml
     hash = {
-      :bare_string        => 'First & Last Name',
-      :pre_escaped_string => 'First &amp; Last Name'
+      bare_string: "First & Last Name",
+      pre_escaped_string: "First &amp; Last Name"
     }.stringify_keys
 
-    expected_xml = '<person><bare-string>First &amp; Last Name</bare-string><pre-escaped-string>First &amp;amp; Last Name</pre-escaped-string></person>'
+    expected_xml = "<person><bare-string>First &amp; Last Name</bare-string><pre-escaped-string>First &amp;amp; Last Name</pre-escaped-string></person>"
     assert_equal expected_xml, hash.to_xml(@xml_options)
   end
 
   def test_unescaping_from_xml
-    xml_string = '<person><bare-string>First &amp; Last Name</bare-string><pre-escaped-string>First &amp;amp; Last Name</pre-escaped-string></person>'
+    xml_string = "<person><bare-string>First &amp; Last Name</bare-string><pre-escaped-string>First &amp;amp; Last Name</pre-escaped-string></person>"
     expected_hash = {
-      :bare_string        => 'First & Last Name',
-      :pre_escaped_string => 'First &amp; Last Name'
+      bare_string: "First & Last Name",
+      pre_escaped_string: "First &amp; Last Name"
     }.stringify_keys
-    assert_equal expected_hash, Hash.from_xml(xml_string)['person']
+    assert_equal expected_hash, Hash.from_xml(xml_string)["person"]
   end
 
   def test_roundtrip_to_xml_from_xml
     hash = {
-      :bare_string        => 'First & Last Name',
-      :pre_escaped_string => 'First &amp; Last Name'
+      bare_string: "First & Last Name",
+      pre_escaped_string: "First &amp; Last Name"
     }.stringify_keys
 
-    assert_equal hash, Hash.from_xml(hash.to_xml(@xml_options))['person']
+    assert_equal hash, Hash.from_xml(hash.to_xml(@xml_options))["person"]
   end
 
   def test_datetime_xml_type_with_utc_time
@@ -1702,7 +1060,7 @@ class HashToXmlTest < ActiveSupport::TestCase
         <alert_at type="datetime">2008-02-10T15:30:45Z</alert_at>
       </alert>
     XML
-    alert_at = Hash.from_xml(alert_xml)['alert']['alert_at']
+    alert_at = Hash.from_xml(alert_xml)["alert"]["alert_at"]
     assert alert_at.utc?
     assert_equal Time.utc(2008, 2, 10, 15, 30, 45), alert_at
   end
@@ -1713,7 +1071,7 @@ class HashToXmlTest < ActiveSupport::TestCase
         <alert_at type="datetime">2008-02-10T10:30:45-05:00</alert_at>
       </alert>
     XML
-    alert_at = Hash.from_xml(alert_xml)['alert']['alert_at']
+    alert_at = Hash.from_xml(alert_xml)["alert"]["alert_at"]
     assert alert_at.utc?
     assert_equal Time.utc(2008, 2, 10, 15, 30, 45), alert_at
   end
@@ -1724,7 +1082,7 @@ class HashToXmlTest < ActiveSupport::TestCase
         <alert_at type="datetime">2050-02-10T15:30:45Z</alert_at>
       </alert>
     XML
-    alert_at = Hash.from_xml(alert_xml)['alert']['alert_at']
+    alert_at = Hash.from_xml(alert_xml)["alert"]["alert_at"]
     assert alert_at.utc?
     assert_equal 2050,  alert_at.year
     assert_equal 2,     alert_at.month
@@ -1735,20 +1093,20 @@ class HashToXmlTest < ActiveSupport::TestCase
   end
 
   def test_to_xml_dups_options
-    options = {:skip_instruct => true}
+    options = { skip_instruct: true }
     {}.to_xml(options)
     # :builder, etc, shouldn't be added to options
-    assert_equal({:skip_instruct => true}, options)
+    assert_equal({ skip_instruct: true }, options)
   end
 
   def test_expansion_count_is_limited
     expected =
       case ActiveSupport::XmlMini.backend.name
-      when 'ActiveSupport::XmlMini_REXML';        RuntimeError
-      when 'ActiveSupport::XmlMini_Nokogiri';     Nokogiri::XML::SyntaxError
-      when 'ActiveSupport::XmlMini_NokogiriSAX';  RuntimeError
-      when 'ActiveSupport::XmlMini_LibXML';       LibXML::XML::Error
-      when 'ActiveSupport::XmlMini_LibXMLSAX';    LibXML::XML::Error
+      when "ActiveSupport::XmlMini_REXML";        RuntimeError
+      when "ActiveSupport::XmlMini_Nokogiri";     Nokogiri::XML::SyntaxError
+      when "ActiveSupport::XmlMini_NokogiriSAX";  RuntimeError
+      when "ActiveSupport::XmlMini_LibXML";       LibXML::XML::Error
+      when "ActiveSupport::XmlMini_LibXMLSAX";    LibXML::XML::Error
       end
 
     assert_raise expected do
diff --git a/activesupport/test/core_ext/integer_ext_test.rb b/activesupport/test/core_ext/integer_ext_test.rb
index 41736fb672..14169b084d 100644
--- a/activesupport/test/core_ext/integer_ext_test.rb
+++ b/activesupport/test/core_ext/integer_ext_test.rb
@@ -1,5 +1,7 @@
-require 'abstract_unit'
-require 'active_support/core_ext/integer'
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "active_support/core_ext/integer"
 
 class IntegerExtTest < ActiveSupport::TestCase
   PRIME = 22953686867719691230002707821868552601124472329079
@@ -19,12 +21,12 @@ class IntegerExtTest < ActiveSupport::TestCase
   def test_ordinalize
     # These tests are mostly just to ensure that the ordinalize method exists.
     # Its results are tested comprehensively in the inflector test cases.
-    assert_equal '1st', 1.ordinalize
-    assert_equal '8th', 8.ordinalize
+    assert_equal "1st", 1.ordinalize
+    assert_equal "8th", 8.ordinalize
   end
 
   def test_ordinal
-    assert_equal 'st', 1.ordinal
-    assert_equal 'th', 8.ordinal
+    assert_equal "st", 1.ordinal
+    assert_equal "th", 8.ordinal
   end
 end
diff --git a/activesupport/test/core_ext/kernel/concern_test.rb b/activesupport/test/core_ext/kernel/concern_test.rb
index 478a00d2d2..b40ff6a623 100644
--- a/activesupport/test/core_ext/kernel/concern_test.rb
+++ b/activesupport/test/core_ext/kernel/concern_test.rb
@@ -1,9 +1,11 @@
-require 'abstract_unit'
-require 'active_support/core_ext/kernel/concern'
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "active_support/core_ext/kernel/concern"
 
 class KernelConcernTest < ActiveSupport::TestCase
   def test_may_be_defined_at_toplevel
-    mod = ::TOPLEVEL_BINDING.eval 'concern(:ToplevelConcern) { }'
+    mod = ::TOPLEVEL_BINDING.eval "concern(:ToplevelConcern) { }"
     assert_equal mod, ::ToplevelConcern
     assert_kind_of ActiveSupport::Concern, ::ToplevelConcern
     assert_not Object.ancestors.include?(::ToplevelConcern), mod.ancestors.inspect
diff --git a/activesupport/test/core_ext/kernel_test.rb b/activesupport/test/core_ext/kernel_test.rb
index 503e6595cb..ef11e10af8 100644
--- a/activesupport/test/core_ext/kernel_test.rb
+++ b/activesupport/test/core_ext/kernel_test.rb
@@ -1,5 +1,7 @@
-require 'abstract_unit'
-require 'active_support/core_ext/kernel'
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "active_support/core_ext/kernel"
 
 class KernelTest < ActiveSupport::TestCase
   def test_silence_warnings
@@ -49,19 +51,3 @@ class KernelSuppressTest < ActiveSupport::TestCase
     suppress(LoadError, ArgumentError) { raise ArgumentError }
   end
 end
-
-class MockStdErr
-  attr_reader :output
-  def puts(message)
-    @output ||= []
-    @output << message
-  end
-
-  def info(message)
-    puts(message)
-  end
-
-  def write(message)
-    puts(message)
-  end
-end
diff --git a/activesupport/test/core_ext/load_error_test.rb b/activesupport/test/core_ext/load_error_test.rb
index b2a75a2bcc..41b11d0c33 100644
--- a/activesupport/test/core_ext/load_error_test.rb
+++ b/activesupport/test/core_ext/load_error_test.rb
@@ -1,26 +1,19 @@
-require 'abstract_unit'
-require 'active_support/core_ext/load_error'
+# frozen_string_literal: true
 
-
-class TestMissingSourceFile < ActiveSupport::TestCase
-  def test_it_is_deprecated
-    assert_deprecated do
-      MissingSourceFile.new
-    end
-  end
-end
+require "abstract_unit"
+require "active_support/core_ext/load_error"
 
 class TestLoadError < ActiveSupport::TestCase
   def test_with_require
-    assert_raise(LoadError) { require 'no_this_file_don\'t_exist' }
+    assert_raise(LoadError) { require "no_this_file_don't_exist" }
   end
   def test_with_load
-    assert_raise(LoadError) { load 'nor_does_this_one' }
+    assert_raise(LoadError) { load "nor_does_this_one" }
   end
   def test_path
-    begin load 'nor/this/one.rb'
+    begin load "nor/this/one.rb"
     rescue LoadError => e
-      assert_equal 'nor/this/one.rb', e.path
+      assert_equal "nor/this/one.rb", e.path
     end
   end
 end
diff --git a/activesupport/test/core_ext/marshal_test.rb b/activesupport/test/core_ext/marshal_test.rb
index 380f64c6fd..7ac051b4b1 100644
--- a/activesupport/test/core_ext/marshal_test.rb
+++ b/activesupport/test/core_ext/marshal_test.rb
@@ -1,6 +1,8 @@
-require 'abstract_unit'
-require 'active_support/core_ext/marshal'
-require 'dependencies_test_helpers'
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "active_support/core_ext/marshal"
+require "dependencies_test_helpers"
 
 class MarshalTest < ActiveSupport::TestCase
   include ActiveSupport::Testing::Isolation
@@ -12,13 +14,26 @@ class MarshalTest < ActiveSupport::TestCase
   end
 
   test "that Marshal#load still works" do
-    sanity_data = ["test", [1, 2, 3], {a: [1, 2, 3]}, ActiveSupport::TestCase]
+    sanity_data = ["test", [1, 2, 3], { a: [1, 2, 3] }, ActiveSupport::TestCase]
     sanity_data.each do |obj|
       dumped = Marshal.dump(obj)
       assert_equal Marshal.method(:load).super_method.call(dumped), Marshal.load(dumped)
     end
   end
 
+  test "that Marshal#load still works when passed a proc" do
+    example_string = "test"
+
+    example_proc = Proc.new do |o|
+      if o.is_a?(String)
+        o.capitalize!
+      end
+    end
+
+    dumped = Marshal.dump(example_string)
+    assert_equal Marshal.load(dumped, example_proc), "Test"
+  end
+
   test "that a missing class is autoloaded from string" do
     dumped = nil
     with_autoloading_fixtures do
diff --git a/activesupport/test/core_ext/module/anonymous_test.rb b/activesupport/test/core_ext/module/anonymous_test.rb
index cb556af772..606f22c9b5 100644
--- a/activesupport/test/core_ext/module/anonymous_test.rb
+++ b/activesupport/test/core_ext/module/anonymous_test.rb
@@ -1,5 +1,7 @@
-require 'abstract_unit'
-require 'active_support/core_ext/module/anonymous'
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "active_support/core_ext/module/anonymous"
 
 class AnonymousTest < ActiveSupport::TestCase
   test "an anonymous class or module are anonymous" do
@@ -11,4 +13,4 @@ class AnonymousTest < ActiveSupport::TestCase
     assert !Kernel.anonymous?
     assert !Object.anonymous?
   end
-end
\ No newline at end of file
+end
diff --git a/activesupport/test/core_ext/module/attr_internal_test.rb b/activesupport/test/core_ext/module/attr_internal_test.rb
index 2aea14cf2b..c2a28eced4 100644
--- a/activesupport/test/core_ext/module/attr_internal_test.rb
+++ b/activesupport/test/core_ext/module/attr_internal_test.rb
@@ -1,5 +1,7 @@
-require 'abstract_unit'
-require 'active_support/core_ext/module/attr_internal'
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "active_support/core_ext/module/attr_internal"
 
 class AttrInternalTest < ActiveSupport::TestCase
   def setup
@@ -10,44 +12,44 @@ class AttrInternalTest < ActiveSupport::TestCase
   def test_reader
     assert_nothing_raised { @target.attr_internal_reader :foo }
 
-    assert !@instance.instance_variable_defined?('@_foo')
+    assert !@instance.instance_variable_defined?("@_foo")
     assert_raise(NoMethodError) { @instance.foo = 1 }
 
-    @instance.instance_variable_set('@_foo', 1)
+    @instance.instance_variable_set("@_foo", 1)
     assert_nothing_raised { assert_equal 1, @instance.foo }
   end
 
   def test_writer
     assert_nothing_raised { @target.attr_internal_writer :foo }
 
-    assert !@instance.instance_variable_defined?('@_foo')
+    assert !@instance.instance_variable_defined?("@_foo")
     assert_nothing_raised { assert_equal 1, @instance.foo = 1 }
 
-    assert_equal 1, @instance.instance_variable_get('@_foo')
+    assert_equal 1, @instance.instance_variable_get("@_foo")
     assert_raise(NoMethodError) { @instance.foo }
   end
 
   def test_accessor
     assert_nothing_raised { @target.attr_internal :foo }
 
-    assert !@instance.instance_variable_defined?('@_foo')
+    assert !@instance.instance_variable_defined?("@_foo")
     assert_nothing_raised { assert_equal 1, @instance.foo = 1 }
 
-    assert_equal 1, @instance.instance_variable_get('@_foo')
+    assert_equal 1, @instance.instance_variable_get("@_foo")
     assert_nothing_raised { assert_equal 1, @instance.foo }
   end
 
   def test_naming_format
-    assert_equal '@_%s', Module.attr_internal_naming_format
-    assert_nothing_raised { Module.attr_internal_naming_format = '@abc%sdef' }
+    assert_equal "@_%s", Module.attr_internal_naming_format
+    assert_nothing_raised { Module.attr_internal_naming_format = "@abc%sdef" }
     @target.attr_internal :foo
 
-    assert !@instance.instance_variable_defined?('@_foo')
-    assert !@instance.instance_variable_defined?('@abcfoodef')
+    assert !@instance.instance_variable_defined?("@_foo")
+    assert !@instance.instance_variable_defined?("@abcfoodef")
     assert_nothing_raised { @instance.foo = 1 }
-    assert !@instance.instance_variable_defined?('@_foo')
-    assert @instance.instance_variable_defined?('@abcfoodef')
+    assert !@instance.instance_variable_defined?("@_foo")
+    assert @instance.instance_variable_defined?("@abcfoodef")
   ensure
-    Module.attr_internal_naming_format = '@_%s'
+    Module.attr_internal_naming_format = "@_%s"
   end
 end
diff --git a/activesupport/test/core_ext/module/attribute_accessor_per_thread_test.rb b/activesupport/test/core_ext/module/attribute_accessor_per_thread_test.rb
index a9fd878b80..e0fbd1002c 100644
--- a/activesupport/test/core_ext/module/attribute_accessor_per_thread_test.rb
+++ b/activesupport/test/core_ext/module/attribute_accessor_per_thread_test.rb
@@ -1,5 +1,7 @@
-require 'abstract_unit'
-require 'active_support/core_ext/module/attribute_accessors_per_thread'
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "active_support/core_ext/module/attribute_accessors_per_thread"
 
 class ModuleAttributeAccessorPerThreadTest < ActiveSupport::TestCase
   def setup
@@ -8,6 +10,12 @@ class ModuleAttributeAccessorPerThreadTest < ActiveSupport::TestCase
       thread_mattr_accessor :bar,  instance_writer: false
       thread_mattr_reader   :shaq, instance_reader: false
       thread_mattr_accessor :camp, instance_accessor: false
+
+      def self.name; "MyClass" end
+    end
+
+    @subclass = Class.new(@class) do
+      def self.name; "SubMyClass" end
     end
 
     @object = @class.new
@@ -57,23 +65,23 @@ class ModuleAttributeAccessorPerThreadTest < ActiveSupport::TestCase
   def test_values_should_not_bleed_between_threads
     threads = []
     threads << Thread.new do
-      @class.foo = 'things'
+      @class.foo = "things"
       sleep 1
-      assert_equal 'things', @class.foo
+      assert_equal "things", @class.foo
     end
 
     threads << Thread.new do
-      @class.foo = 'other things'
+      @class.foo = "other things"
       sleep 1
-      assert_equal 'other things', @class.foo      
+      assert_equal "other things", @class.foo
     end
-    
+
     threads << Thread.new do
-      @class.foo = 'really other things'
+      @class.foo = "really other things"
       sleep 1
-      assert_equal 'really other things', @class.foo      
+      assert_equal "really other things", @class.foo
     end
-    
+
     threads.each { |t| t.join }
   end
 
@@ -108,8 +116,18 @@ class ModuleAttributeAccessorPerThreadTest < ActiveSupport::TestCase
   end
 
   def test_should_return_same_value_by_class_or_instance_accessor
-    @class.foo = 'fries'
+    @class.foo = "fries"
 
     assert_equal @class.foo, @object.foo
   end
+
+  def test_should_not_affect_superclass_if_subclass_set_value
+    @class.foo = "super"
+    assert_equal "super", @class.foo
+    assert_nil @subclass.foo
+
+    @subclass.foo = "sub"
+    assert_equal "super", @class.foo
+    assert_equal "sub", @subclass.foo
+  end
 end
diff --git a/activesupport/test/core_ext/module/attribute_accessor_test.rb b/activesupport/test/core_ext/module/attribute_accessor_test.rb
index 0b0f3a2808..f1d6859a88 100644
--- a/activesupport/test/core_ext/module/attribute_accessor_test.rb
+++ b/activesupport/test/core_ext/module/attribute_accessor_test.rb
@@ -1,18 +1,27 @@
-require 'abstract_unit'
-require 'active_support/core_ext/module/attribute_accessors'
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "active_support/core_ext/module/attribute_accessors"
 
 class ModuleAttributeAccessorTest < ActiveSupport::TestCase
   def setup
     m = @module = Module.new do
       mattr_accessor :foo
-      mattr_accessor :bar, :instance_writer => false
-      mattr_reader   :shaq, :instance_reader => false
-      mattr_accessor :camp, :instance_accessor => false
+      mattr_accessor :bar, instance_writer: false
+      mattr_reader   :shaq, instance_reader: false
+      mattr_accessor :camp, instance_accessor: false
 
-      cattr_accessor(:defa) { 'default_accessor_value' }
-      cattr_reader(:defr) { 'default_reader_value' }
-      cattr_writer(:defw) { 'default_writer_value' }
+      cattr_accessor(:defa) { "default_accessor_value" }
+      cattr_reader(:defr) { "default_reader_value" }
+      cattr_writer(:defw) { "default_writer_value" }
+      cattr_accessor(:deff) { false }
       cattr_accessor(:quux) { :quux }
+
+      cattr_accessor :def_accessor, default: "default_accessor_value"
+      cattr_reader :def_reader, default: "default_reader_value"
+      cattr_writer :def_writer, default: "default_writer_value"
+      cattr_accessor :def_false, default: false
+      cattr_accessor(:def_priority, default: false) { :no_priority }
     end
     @class = Class.new
     @class.instance_eval { include m }
@@ -24,6 +33,21 @@ class ModuleAttributeAccessorTest < ActiveSupport::TestCase
     assert_nil @object.foo
   end
 
+  def test_mattr_default_keyword_arguments
+    assert_equal "default_accessor_value", @module.def_accessor
+    assert_equal "default_reader_value", @module.def_reader
+    assert_equal "default_writer_value", @module.class_variable_get(:@@def_writer)
+  end
+
+  def test_mattr_can_default_to_false
+    assert_equal false, @module.def_false
+    assert_equal false, @module.deff
+  end
+
+  def test_mattr_default_priority
+    assert_equal false, @module.def_priority
+  end
+
   def test_should_set_mattr_value
     @module.foo = :test
     assert_equal :test, @object.foo
@@ -86,14 +110,28 @@ class ModuleAttributeAccessorTest < ActiveSupport::TestCase
   end
 
   def test_should_use_default_value_if_block_passed
-    assert_equal 'default_accessor_value', @module.defa
-    assert_equal 'default_reader_value', @module.defr
-    assert_equal 'default_writer_value', @module.class_variable_get('@@defw')
+    assert_equal "default_accessor_value", @module.defa
+    assert_equal "default_reader_value", @module.defr
+    assert_equal "default_writer_value", @module.class_variable_get("@@defw")
   end
 
-  def test_should_not_invoke_default_value_block_multiple_times
+  def test_method_invocation_should_not_invoke_the_default_block
     count = 0
-    @module.cattr_accessor(:defcount){ count += 1 }
+
+    @module.cattr_accessor(:defcount) { count += 1 }
+
     assert_equal 1, count
+    assert_no_difference "count" do
+      @module.defcount
+    end
+  end
+
+  def test_declaring_multiple_attributes_at_once_invokes_the_block_multiple_times
+    count = 0
+
+    @module.cattr_accessor(:defn1, :defn2) { count += 1 }
+
+    assert_equal 1, @module.defn1
+    assert_equal 2, @module.defn2
   end
 end
diff --git a/activesupport/test/core_ext/module/attribute_aliasing_test.rb b/activesupport/test/core_ext/module/attribute_aliasing_test.rb
index 29c3053b47..187a0f4da2 100644
--- a/activesupport/test/core_ext/module/attribute_aliasing_test.rb
+++ b/activesupport/test/core_ext/module/attribute_aliasing_test.rb
@@ -1,5 +1,7 @@
-require 'abstract_unit'
-require 'active_support/core_ext/module/aliasing'
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "active_support/core_ext/module/aliasing"
 
 module AttributeAliasing
   class Content
@@ -52,8 +54,8 @@ class AttributeAliasingTest < ActiveSupport::TestCase
     assert_equal "No, really, this is not a joke.", e.Data
     assert e.Data?
 
-    e.Data = "Uppercased methods are teh suck"
-    assert_equal "Uppercased methods are teh suck", e.body
+    e.Data = "Uppercased methods are the suck"
+    assert_equal "Uppercased methods are the suck", e.body
     assert e.body?
   end
 end
diff --git a/activesupport/test/core_ext/module/concerning_test.rb b/activesupport/test/core_ext/module/concerning_test.rb
index 07d860b71c..192c3d5a9c 100644
--- a/activesupport/test/core_ext/module/concerning_test.rb
+++ b/activesupport/test/core_ext/module/concerning_test.rb
@@ -1,10 +1,12 @@
-require 'abstract_unit'
-require 'active_support/core_ext/module/concerning'
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "active_support/core_ext/module/concerning"
 
 class ModuleConcerningTest < ActiveSupport::TestCase
   def test_concerning_declares_a_concern_and_includes_it_immediately
-    klass = Class.new { concerning(:Foo) { } }
-    assert klass.ancestors.include?(klass::Foo), klass.ancestors.inspect
+    klass = Class.new { concerning(:Foo) {} }
+    assert_includes klass.ancestors, klass::Foo, klass.ancestors.inspect
   end
 end
 
@@ -21,13 +23,13 @@ class ModuleConcernTest < ActiveSupport::TestCase
     assert klass.const_defined?(:Baz, false)
     assert !ModuleConcernTest.const_defined?(:Baz)
     assert_kind_of ActiveSupport::Concern, klass::Baz
-    assert !klass.ancestors.include?(klass::Baz), klass.ancestors.inspect
+    assert_not_includes klass.ancestors, klass::Baz, klass.ancestors.inspect
 
     # Public method visibility by default
-    assert klass::Baz.public_instance_methods.map(&:to_s).include?('should_be_public')
+    assert_includes klass::Baz.public_instance_methods.map(&:to_s), "should_be_public"
 
     # Calls included hook
-    assert_equal 1, Class.new { include klass::Baz }.instance_variable_get('@foo')
+    assert_equal 1, Class.new { include klass::Baz }.instance_variable_get("@foo")
   end
 
   class Foo
diff --git a/activesupport/test/core_ext/module/introspection_test.rb b/activesupport/test/core_ext/module/introspection_test.rb
new file mode 100644
index 0000000000..76d3012239
--- /dev/null
+++ b/activesupport/test/core_ext/module/introspection_test.rb
@@ -0,0 +1,39 @@
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "active_support/core_ext/module/introspection"
+
+module ParentA
+  module B
+    module C; end
+    module FrozenC; end
+    FrozenC.freeze
+  end
+
+  module FrozenB; end
+  FrozenB.freeze
+end
+
+class IntrospectionTest < ActiveSupport::TestCase
+  def test_parent_name
+    assert_equal "ParentA", ParentA::B.parent_name
+    assert_equal "ParentA::B", ParentA::B::C.parent_name
+    assert_nil ParentA.parent_name
+  end
+
+  def test_parent_name_when_frozen
+    assert_equal "ParentA", ParentA::FrozenB.parent_name
+    assert_equal "ParentA::B", ParentA::B::FrozenC.parent_name
+  end
+
+  def test_parent
+    assert_equal ParentA::B, ParentA::B::C.parent
+    assert_equal ParentA, ParentA::B.parent
+    assert_equal Object, ParentA.parent
+  end
+
+  def test_parents
+    assert_equal [ParentA::B, ParentA, Object], ParentA::B::C.parents
+    assert_equal [ParentA, Object], ParentA::B.parents
+  end
+end
diff --git a/activesupport/test/core_ext/module/qualified_const_test.rb b/activesupport/test/core_ext/module/qualified_const_test.rb
deleted file mode 100644
index a3146cabe1..0000000000
--- a/activesupport/test/core_ext/module/qualified_const_test.rb
+++ /dev/null
@@ -1,118 +0,0 @@
-require 'abstract_unit'
-require 'active_support/core_ext/module/qualified_const'
-
-module QualifiedConstTestMod
-  X = false
-
-  module M
-    X = 1
-
-    class C
-      X = 2
-    end
-  end
-
-  module N
-    include M
-  end
-end
-
-class QualifiedConstTest < ActiveSupport::TestCase
-  test "Object.qualified_const_defined?" do
-    assert_deprecated do
-      assert Object.qualified_const_defined?("QualifiedConstTestMod")
-      assert !Object.qualified_const_defined?("NonExistingQualifiedConstTestMod")
-
-      assert Object.qualified_const_defined?("QualifiedConstTestMod::X")
-      assert !Object.qualified_const_defined?("QualifiedConstTestMod::Y")
-
-      assert Object.qualified_const_defined?("QualifiedConstTestMod::M::X")
-      assert !Object.qualified_const_defined?("QualifiedConstTestMod::M::Y")
-
-      if Module.method(:const_defined?).arity == 1
-        assert !Object.qualified_const_defined?("QualifiedConstTestMod::N::X")
-      else
-        assert Object.qualified_const_defined?("QualifiedConstTestMod::N::X")
-        assert !Object.qualified_const_defined?("QualifiedConstTestMod::N::X", false)
-        assert Object.qualified_const_defined?("QualifiedConstTestMod::N::X", true)
-      end
-    end
-  end
-
-  test "mod.qualified_const_defined?" do
-    assert_deprecated do
-      assert QualifiedConstTestMod.qualified_const_defined?("M")
-      assert !QualifiedConstTestMod.qualified_const_defined?("NonExistingM")
-
-      assert QualifiedConstTestMod.qualified_const_defined?("M::X")
-      assert !QualifiedConstTestMod.qualified_const_defined?("M::Y")
-
-      assert QualifiedConstTestMod.qualified_const_defined?("M::C::X")
-      assert !QualifiedConstTestMod.qualified_const_defined?("M::C::Y")
-
-      if Module.method(:const_defined?).arity == 1
-        assert !QualifiedConstTestMod.qualified_const_defined?("QualifiedConstTestMod::N::X")
-      else
-        assert QualifiedConstTestMod.qualified_const_defined?("N::X")
-        assert !QualifiedConstTestMod.qualified_const_defined?("N::X", false)
-        assert QualifiedConstTestMod.qualified_const_defined?("N::X", true)
-      end
-    end
-  end
-
-  test "qualified_const_get" do
-    assert_deprecated do
-      assert_equal false, Object.qualified_const_get("QualifiedConstTestMod::X")
-      assert_equal false, QualifiedConstTestMod.qualified_const_get("X")
-      assert_equal 1, QualifiedConstTestMod.qualified_const_get("M::X")
-      assert_equal 1, QualifiedConstTestMod.qualified_const_get("N::X")
-      assert_equal 2, QualifiedConstTestMod.qualified_const_get("M::C::X")
-
-      assert_raise(NameError) { QualifiedConstTestMod.qualified_const_get("M::C::Y")}
-    end
-  end
-
-  test "qualified_const_set" do
-    assert_deprecated do
-      begin
-        m = Module.new
-        assert_equal m, Object.qualified_const_set("QualifiedConstTestMod2", m)
-        assert_equal m, ::QualifiedConstTestMod2
-
-        # We are going to assign to existing constants on purpose, so silence warnings.
-        silence_warnings do
-          assert_equal true, QualifiedConstTestMod.qualified_const_set("QualifiedConstTestMod::X", true)
-          assert_equal true, QualifiedConstTestMod::X
-
-          assert_equal 10, QualifiedConstTestMod::M.qualified_const_set("X", 10)
-          assert_equal 10, QualifiedConstTestMod::M::X
-        end
-      ensure
-        silence_warnings do
-          QualifiedConstTestMod.qualified_const_set('QualifiedConstTestMod::X', false)
-          QualifiedConstTestMod::M.qualified_const_set('X', 1)
-        end
-      end
-    end
-  end
-
-  test "reject absolute paths" do
-    assert_deprecated do
-      assert_raise_with_message(NameError, "wrong constant name ::X") { Object.qualified_const_defined?("::X")}
-      assert_raise_with_message(NameError, "wrong constant name ::X") { Object.qualified_const_defined?("::X::Y")}
-
-      assert_raise_with_message(NameError, "wrong constant name ::X") { Object.qualified_const_get("::X")}
-      assert_raise_with_message(NameError, "wrong constant name ::X") { Object.qualified_const_get("::X::Y")}
-
-      assert_raise_with_message(NameError, "wrong constant name ::X") { Object.qualified_const_set("::X", nil)}
-      assert_raise_with_message(NameError, "wrong constant name ::X") { Object.qualified_const_set("::X::Y", nil)}
-    end
-  end
-
-  private
-
-  def assert_raise_with_message(expected_exception, expected_message, &block)
-    exception = assert_raise(expected_exception, &block)
-    assert_equal expected_message, exception.message
-  end
-end
diff --git a/activesupport/test/core_ext/module/reachable_test.rb b/activesupport/test/core_ext/module/reachable_test.rb
index 80eb31a5c4..097a72fa5b 100644
--- a/activesupport/test/core_ext/module/reachable_test.rb
+++ b/activesupport/test/core_ext/module/reachable_test.rb
@@ -1,15 +1,21 @@
-require 'abstract_unit'
-require 'active_support/core_ext/module/reachable'
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "active_support/core_ext/module/reachable"
 
 class AnonymousTest < ActiveSupport::TestCase
   test "an anonymous class or module is not reachable" do
-    assert !Module.new.reachable?
-    assert !Class.new.reachable?
+    assert_deprecated do
+      assert !Module.new.reachable?
+      assert !Class.new.reachable?
+    end
   end
 
   test "ordinary named classes or modules are reachable" do
-    assert Kernel.reachable?
-    assert Object.reachable?
+    assert_deprecated do
+      assert Kernel.reachable?
+      assert Object.reachable?
+    end
   end
 
   test "a named class or module whose constant has gone is not reachable" do
@@ -19,8 +25,10 @@ class AnonymousTest < ActiveSupport::TestCase
     self.class.send(:remove_const, :C)
     self.class.send(:remove_const, :M)
 
-    assert !c.reachable?
-    assert !m.reachable?
+    assert_deprecated do
+      assert !c.reachable?
+      assert !m.reachable?
+    end
   end
 
   test "a named class or module whose constants store different objects are not reachable" do
@@ -33,9 +41,11 @@ class AnonymousTest < ActiveSupport::TestCase
     eval "class C; end"
     eval "module M; end"
 
-    assert C.reachable?
-    assert M.reachable?
-    assert !c.reachable?
-    assert !m.reachable?
+    assert_deprecated do
+      assert C.reachable?
+      assert M.reachable?
+      assert !c.reachable?
+      assert !m.reachable?
+    end
   end
-end
\ No newline at end of file
+end
diff --git a/activesupport/test/core_ext/module/remove_method_test.rb b/activesupport/test/core_ext/module/remove_method_test.rb
index 0d684dc70e..8493be8d08 100644
--- a/activesupport/test/core_ext/module/remove_method_test.rb
+++ b/activesupport/test/core_ext/module/remove_method_test.rb
@@ -1,51 +1,52 @@
-require 'abstract_unit'
-require 'active_support/core_ext/module/remove_method'
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "active_support/core_ext/module/remove_method"
 
 module RemoveMethodTests
   class A
     def do_something
-      return 1
+      1
     end
 
     def do_something_protected
-      return 1
+      1
     end
     protected :do_something_protected
 
     def do_something_private
-      return 1
+      1
     end
     private :do_something_private
 
     class << self
       def do_something_else
-        return 2
+        2
       end
     end
   end
 end
 
 class RemoveMethodTest < ActiveSupport::TestCase
-
   def test_remove_method_from_an_object
-    RemoveMethodTests::A.class_eval{
-      self.remove_possible_method(:do_something)
+    RemoveMethodTests::A.class_eval {
+      remove_possible_method(:do_something)
     }
     assert !RemoveMethodTests::A.new.respond_to?(:do_something)
   end
 
   def test_remove_singleton_method_from_an_object
-    RemoveMethodTests::A.class_eval{
-      self.remove_possible_singleton_method(:do_something_else)
+    RemoveMethodTests::A.class_eval {
+      remove_possible_singleton_method(:do_something_else)
     }
     assert !RemoveMethodTests::A.respond_to?(:do_something_else)
   end
 
   def test_redefine_method_in_an_object
-    RemoveMethodTests::A.class_eval{
-      self.redefine_method(:do_something) { return 100 }
-      self.redefine_method(:do_something_protected) { return 100 }
-      self.redefine_method(:do_something_private) { return 100 }
+    RemoveMethodTests::A.class_eval {
+      redefine_method(:do_something) { return 100 }
+      redefine_method(:do_something_protected) { return 100 }
+      redefine_method(:do_something_private) { return 100 }
     }
     assert_equal 100, RemoveMethodTests::A.new.do_something
     assert_equal 100, RemoveMethodTests::A.new.send(:do_something_protected)
@@ -55,5 +56,4 @@ class RemoveMethodTest < ActiveSupport::TestCase
     assert RemoveMethodTests::A.protected_method_defined? :do_something_protected
     assert RemoveMethodTests::A.private_method_defined? :do_something_private
   end
-
 end
diff --git a/activesupport/test/core_ext/module_test.rb b/activesupport/test/core_ext/module_test.rb
index 566f29b470..e918823074 100644
--- a/activesupport/test/core_ext/module_test.rb
+++ b/activesupport/test/core_ext/module_test.rb
@@ -1,80 +1,63 @@
-require 'abstract_unit'
-require 'active_support/core_ext/module'
+# frozen_string_literal: true
 
-module One
-  Constant1 = "Hello World"
-  Constant2 = "What's up?"
-end
-
-class Ab
-  include One
-  Constant1 = "Hello World" # Will have different object id than One::Constant1
-  Constant3 = "Goodbye World"
-end
-
-module Yz
-  module Zy
-    class Cd
-      include One
-    end
-  end
-end
+require "abstract_unit"
+require "active_support/core_ext/module"
 
 Somewhere = Struct.new(:street, :city) do
   attr_accessor :name
 end
 
-class Someone < Struct.new(:name, :place)
-  delegate :street, :city, :to_f, :to => :place
-  delegate :name=, :to => :place, :prefix => true
-  delegate :upcase, :to => "place.city"
-  delegate :table_name, :to => :class
-  delegate :table_name, :to => :class, :prefix => true
+Someone = Struct.new(:name, :place) do
+  delegate :street, :city, :to_f, to: :place
+  delegate :name=, to: :place, prefix: true
+  delegate :upcase, to: "place.city"
+  delegate :table_name, to: :class
+  delegate :table_name, to: :class, prefix: true
 
   def self.table_name
-    'some_table'
+    "some_table"
   end
 
-  FAILED_DELEGATE_LINE = __LINE__ + 1
-  delegate :foo, :to => :place
+  self::FAILED_DELEGATE_LINE = __LINE__ + 1
+  delegate :foo, to: :place
 
-  FAILED_DELEGATE_LINE_2 = __LINE__ + 1
-  delegate :bar, :to => :place, :allow_nil => true
+  self::FAILED_DELEGATE_LINE_2 = __LINE__ + 1
+  delegate :bar, to: :place, allow_nil: true
 
   private
 
-  def private_name
-    "Private"
-  end
+    def private_name
+      "Private"
+    end
 end
 
-Invoice   = Struct.new(:client) do
-  delegate :street, :city, :name, :to => :client, :prefix => true
-  delegate :street, :city, :name, :to => :client, :prefix => :customer
+Invoice = Struct.new(:client) do
+  delegate :street, :city, :name, to: :client, prefix: true
+  delegate :street, :city, :name, to: :client, prefix: :customer
 end
 
-Project   = Struct.new(:description, :person) do
-  delegate :name, :to => :person, :allow_nil => true
-  delegate :to_f, :to => :description, :allow_nil => true
+Project = Struct.new(:description, :person) do
+  delegate :name, to: :person, allow_nil: true
+  delegate :to_f, to: :description, allow_nil: true
 end
 
 Developer = Struct.new(:client) do
-  delegate :name, :to => :client, :prefix => nil
+  delegate :name, to: :client, prefix: nil
 end
 
 Event = Struct.new(:case) do
-  delegate :foo, :to => :case
+  delegate :foo, to: :case
 end
 
 Tester = Struct.new(:client) do
-  delegate :name, :to => :client, :prefix => false
+  delegate :name, to: :client, prefix: false
 
   def foo; 1; end
 end
 
 Product = Struct.new(:name) do
-  delegate :name, :to => :manufacturer, :prefix => true
-  delegate :name, :to => :type, :prefix => true
+  delegate :name, to: :manufacturer, prefix: true
+  delegate :name, to: :type, prefix: true
 
   def manufacturer
     @manufacturer ||= begin
@@ -89,7 +72,23 @@ Product = Struct.new(:name) do
   end
 end
 
+module ExtraMissing
+  def method_missing(sym, *args)
+    if sym == :extra_missing
+      42
+    else
+      super
+    end
+  end
+
+  def respond_to_missing?(sym, priv = false)
+    sym == :extra_missing || super
+  end
+end
+
 DecoratedTester = Struct.new(:client) do
+  include ExtraMissing
+
   delegate_missing_to :client
 end
 
@@ -114,15 +113,15 @@ HasBlock = Struct.new(:block) do
 end
 
 class ParameterSet
-  delegate :[], :[]=, :to => :@params
+  delegate :[], :[]=, to: :@params
 
   def initialize
-    @params = {:foo => "bar"}
+    @params = { foo: "bar" }
   end
 end
 
 class Name
-  delegate :upcase, :to => :@full_name
+  delegate :upcase, to: :@full_name
 
   def initialize(first, last)
     @full_name = "#{first} #{last}"
@@ -132,8 +131,8 @@ end
 class SideEffect
   attr_reader :ints
 
-  delegate :to_i, :to => :shift, :allow_nil => true
-  delegate :to_s, :to => :shift
+  delegate :to_i, to: :shift, allow_nil: true
+  delegate :to_s, to: :shift
 
   def initialize
     @ints = [1, 2, 3]
@@ -180,8 +179,8 @@ class ModuleTest < ActiveSupport::TestCase
   end
 
   def test_delegation_to_class_method
-    assert_equal 'some_table', @david.table_name
-    assert_equal 'some_table', @david.class_table_name
+    assert_equal "some_table", @david.table_name
+    assert_equal "some_table", @david.class_table_name
   end
 
   def test_missing_delegation_target
@@ -189,7 +188,7 @@ class ModuleTest < ActiveSupport::TestCase
       Name.send :delegate, :nowhere
     end
     assert_raise(ArgumentError) do
-      Name.send :delegate, :noplace, :tos => :hollywood
+      Name.send :delegate, :noplace, tos: :hollywood
     end
   end
 
@@ -210,21 +209,21 @@ class ModuleTest < ActiveSupport::TestCase
 
   def test_delegation_prefix
     invoice = Invoice.new(@david)
-    assert_equal invoice.client_name, "David"
-    assert_equal invoice.client_street, "Paulina"
-    assert_equal invoice.client_city, "Chicago"
+    assert_equal "David", invoice.client_name
+    assert_equal "Paulina", invoice.client_street
+    assert_equal "Chicago", invoice.client_city
   end
 
   def test_delegation_custom_prefix
     invoice = Invoice.new(@david)
-    assert_equal invoice.customer_name, "David"
-    assert_equal invoice.customer_street, "Paulina"
-    assert_equal invoice.customer_city, "Chicago"
+    assert_equal "David", invoice.customer_name
+    assert_equal "Paulina", invoice.customer_street
+    assert_equal "Chicago", invoice.customer_city
   end
 
   def test_delegation_prefix_with_nil_or_false
-    assert_equal Developer.new(@david).name, "David"
-    assert_equal Tester.new(@david).name, "David"
+    assert_equal "David", Developer.new(@david).name
+    assert_equal "David", Tester.new(@david).name
   end
 
   def test_delegation_prefix_with_instance_variable
@@ -233,14 +232,14 @@ class ModuleTest < ActiveSupport::TestCase
         def initialize(client)
           @client = client
         end
-        delegate :name, :address, :to => :@client, :prefix => true
+        delegate :name, :address, to: :@client, prefix: true
       end
     end
   end
 
   def test_delegation_with_allow_nil
     rails = Project.new("Rails", Someone.new("David"))
-    assert_equal rails.name, "David"
+    assert_equal "David", rails.name
   end
 
   def test_delegation_with_allow_nil_and_nil_value
@@ -261,7 +260,7 @@ class ModuleTest < ActiveSupport::TestCase
 
   def test_delegation_with_allow_nil_and_nil_value_and_prefix
     Project.class_eval do
-      delegate :name, :to => :person, :allow_nil => true, :prefix => true
+      delegate :name, to: :person, allow_nil: true, prefix: true
     end
     rails = Project.new("Rails")
     assert_nil rails.person_name
@@ -290,7 +289,7 @@ class ModuleTest < ActiveSupport::TestCase
     assert_nothing_raised do
       Class.new(parent) do
         class << self
-          delegate :parent_method, :to => :superclass
+          delegate :parent_method, to: :superclass
         end
       end
     end
@@ -312,7 +311,7 @@ class ModuleTest < ActiveSupport::TestCase
   rescue NoMethodError => e
     file_and_line = "#{__FILE__}:#{Someone::FAILED_DELEGATE_LINE}"
     # We can't simply check the first line of the backtrace, because JRuby reports the call to __send__ in the backtrace.
-    assert e.backtrace.any?{|a| a.include?(file_and_line)},
+    assert e.backtrace.any? { |a| a.include?(file_and_line) },
            "[#{e.backtrace.inspect}] did not include [#{file_and_line}]"
   end
 
@@ -322,7 +321,7 @@ class ModuleTest < ActiveSupport::TestCase
   rescue NoMethodError => e
     file_and_line = "#{__FILE__}:#{Someone::FAILED_DELEGATE_LINE_2}"
     # We can't simply check the first line of the backtrace, because JRuby reports the call to __send__ in the backtrace.
-    assert e.backtrace.any?{|a| a.include?(file_and_line)},
+    assert e.backtrace.any? { |a| a.include?(file_and_line) },
            "[#{e.backtrace.inspect}] did not include [#{file_and_line}]"
   end
 
@@ -332,12 +331,12 @@ class ModuleTest < ActiveSupport::TestCase
     assert_equal 1, se.to_i
     assert_equal [2, 3], se.ints
 
-    assert_equal '2', se.to_s
+    assert_equal "2", se.to_s
     assert_equal [3], se.ints
   end
 
   def test_delegation_doesnt_mask_nested_no_method_error_on_nil_receiver
-    product = Product.new('Widget')
+    product = Product.new("Widget")
 
     # Nested NoMethodError is a different name from the delegation
     assert_raise(NoMethodError) { product.manufacturer_name }
@@ -351,15 +350,15 @@ class ModuleTest < ActiveSupport::TestCase
     assert has_block.hello?
   end
 
-  def test_delegate_to_missing_with_method
+  def test_delegate_missing_to_with_method
     assert_equal "David", DecoratedTester.new(@david).name
   end
 
-  def test_delegate_to_missing_with_reserved_methods
+  def test_delegate_missing_to_with_reserved_methods
     assert_equal "David", DecoratedReserved.new(@david).name
   end
 
-  def test_delegate_to_missing_does_not_delegate_to_private_methods
+  def test_delegate_missing_to_does_not_delegate_to_private_methods
     e = assert_raises(NoMethodError) do
       DecoratedReserved.new(@david).private_name
     end
@@ -367,7 +366,7 @@ class ModuleTest < ActiveSupport::TestCase
     assert_match(/undefined method `private_name' for/, e.message)
   end
 
-  def test_delegate_to_missing_does_not_delegate_to_fake_methods
+  def test_delegate_missing_to_does_not_delegate_to_fake_methods
     e = assert_raises(NoMethodError) do
       DecoratedReserved.new(@david).my_fake_method
     end
@@ -375,245 +374,70 @@ class ModuleTest < ActiveSupport::TestCase
     assert_match(/undefined method `my_fake_method' for/, e.message)
   end
 
-  def test_parent
-    assert_equal Yz::Zy, Yz::Zy::Cd.parent
-    assert_equal Yz, Yz::Zy.parent
-    assert_equal Object, Yz.parent
-  end
-
-  def test_parents
-    assert_equal [Yz::Zy, Yz, Object], Yz::Zy::Cd.parents
-    assert_equal [Yz, Object], Yz::Zy.parents
-  end
-
-  def test_local_constants
-    ActiveSupport::Deprecation.silence do
-      assert_equal %w(Constant1 Constant3), Ab.local_constants.sort.map(&:to_s)
-    end
-  end
-
-  def test_local_constants_is_deprecated
-    assert_deprecated { Ab.local_constants.sort.map(&:to_s) }
-  end
-end
-
-module BarMethodAliaser
-  def self.included(foo_class)
-    foo_class.class_eval do
-      include BarMethods
-      alias_method_chain :bar, :baz
-    end
-  end
-end
-
-module BarMethods
-  def bar_with_baz
-    bar_without_baz << '_with_baz'
-  end
-
-  def quux_with_baz!
-    quux_without_baz! << '_with_baz'
-  end
-
-  def quux_with_baz?
-    false
-  end
-
-  def quux_with_baz=(v)
-    send(:quux_without_baz=, v) << '_with_baz'
-  end
-
-  def duck_with_orange
-    duck_without_orange << '_with_orange'
-  end
-end
-
-class MethodAliasingTest < ActiveSupport::TestCase
-  def setup
-    Object.const_set :FooClassWithBarMethod, Class.new { def bar() 'bar' end }
-    @instance = FooClassWithBarMethod.new
-  end
-
-  def teardown
-    Object.instance_eval { remove_const :FooClassWithBarMethod }
-  end
-
-  def test_alias_method_chain_deprecated
-    assert_deprecated(/alias_method_chain/) do
-      Module.new do
-        def base
-        end
-
-        def base_with_deprecated
-        end
-
-        alias_method_chain :base, :deprecated
-      end
+  def test_delegate_missing_to_raises_delegation_error_if_target_nil
+    e = assert_raises(Module::DelegationError) do
+      DecoratedTester.new(nil).name
     end
-  end
-
-  def test_alias_method_chain
-    assert_deprecated(/alias_method_chain/) do
-      assert @instance.respond_to?(:bar)
-      feature_aliases = [:bar_with_baz, :bar_without_baz]
-
-      feature_aliases.each do |method|
-        assert !@instance.respond_to?(method)
-      end
-
-      assert_equal 'bar', @instance.bar
-
-      FooClassWithBarMethod.class_eval { include BarMethodAliaser }
 
-      feature_aliases.each do |method|
-        assert_respond_to @instance, method
-      end
-
-      assert_equal 'bar_with_baz', @instance.bar
-      assert_equal 'bar', @instance.bar_without_baz
-    end
+    assert_equal "name delegated to client, but client is nil", e.message
   end
 
-  def test_alias_method_chain_with_punctuation_method
-    assert_deprecated(/alias_method_chain/) do
-      FooClassWithBarMethod.class_eval do
-        def quux!; 'quux' end
-      end
-
-      assert !@instance.respond_to?(:quux_with_baz!)
-      FooClassWithBarMethod.class_eval do
-        include BarMethodAliaser
-        alias_method_chain :quux!, :baz
-      end
-      assert_respond_to @instance, :quux_with_baz!
+  def test_delegate_missing_to_affects_respond_to
+    assert DecoratedTester.new(@david).respond_to?(:name)
+    assert_not DecoratedTester.new(@david).respond_to?(:private_name)
+    assert_not DecoratedTester.new(@david).respond_to?(:my_fake_method)
 
-      assert_equal 'quux_with_baz', @instance.quux!
-      assert_equal 'quux', @instance.quux_without_baz!
-    end
+    assert DecoratedTester.new(@david).respond_to?(:name, true)
+    assert_not DecoratedTester.new(@david).respond_to?(:private_name, true)
+    assert_not DecoratedTester.new(@david).respond_to?(:my_fake_method, true)
   end
 
-  def test_alias_method_chain_with_same_names_between_predicates_and_bang_methods
-    assert_deprecated(/alias_method_chain/) do
-      FooClassWithBarMethod.class_eval do
-        def quux!; 'quux!' end
-        def quux?; true end
-        def quux=(v); 'quux=' end
-      end
-
-      assert !@instance.respond_to?(:quux_with_baz!)
-      assert !@instance.respond_to?(:quux_with_baz?)
-      assert !@instance.respond_to?(:quux_with_baz=)
+  def test_delegate_missing_to_respects_superclass_missing
+    assert_equal 42, DecoratedTester.new(@david).extra_missing
 
-      FooClassWithBarMethod.class_eval { include BarMethodAliaser }
-      assert_respond_to @instance, :quux_with_baz!
-      assert_respond_to @instance, :quux_with_baz?
-      assert_respond_to @instance, :quux_with_baz=
-
-
-      FooClassWithBarMethod.alias_method_chain :quux!, :baz
-      assert_equal 'quux!_with_baz', @instance.quux!
-      assert_equal 'quux!', @instance.quux_without_baz!
-
-      FooClassWithBarMethod.alias_method_chain :quux?, :baz
-      assert_equal false, @instance.quux?
-      assert_equal true,  @instance.quux_without_baz?
-
-      FooClassWithBarMethod.alias_method_chain :quux=, :baz
-      assert_equal 'quux=_with_baz', @instance.send(:quux=, 1234)
-      assert_equal 'quux=', @instance.send(:quux_without_baz=, 1234)
-    end
+    assert_respond_to DecoratedTester.new(@david), :extra_missing
   end
 
-  def test_alias_method_chain_with_feature_punctuation
-    assert_deprecated(/alias_method_chain/) do
-      FooClassWithBarMethod.class_eval do
-        def quux; 'quux' end
-        def quux?; 'quux?' end
-        include BarMethodAliaser
-        alias_method_chain :quux, :baz!
-      end
-
-      assert_nothing_raised do
-        assert_equal 'quux_with_baz', @instance.quux_with_baz!
-      end
-
-      assert_raise(NameError) do
-        FooClassWithBarMethod.alias_method_chain :quux?, :baz!
-      end
-    end
+  def test_delegate_with_case
+    event = Event.new(Tester.new)
+    assert_equal 1, event.foo
   end
 
-  def test_alias_method_chain_yields_target_and_punctuation
-    assert_deprecated(/alias_method_chain/) do
-      args = nil
-
-      FooClassWithBarMethod.class_eval do
-        def quux?; end
-        include BarMethods
-
-        FooClassWithBarMethod.alias_method_chain :quux?, :baz do |target, punctuation|
-          args = [target, punctuation]
-        end
+  def test_private_delegate
+    location = Class.new do
+      def initialize(place)
+        @place = place
       end
 
-      assert_not_nil args
-      assert_equal 'quux', args[0]
-      assert_equal '?', args[1]
+      private(*delegate(:street, :city, to: :@place))
     end
-  end
 
-  def test_alias_method_chain_preserves_private_method_status
-    assert_deprecated(/alias_method_chain/) do
-      FooClassWithBarMethod.class_eval do
-        def duck; 'duck' end
-        include BarMethodAliaser
-        private :duck
-        alias_method_chain :duck, :orange
-      end
+    place = location.new(Somewhere.new("Such street", "Sad city"))
 
-      assert_raise NoMethodError do
-        @instance.duck
-      end
+    assert_not place.respond_to?(:street)
+    assert_not place.respond_to?(:city)
 
-      assert_equal 'duck_with_orange', @instance.instance_eval { duck }
-      assert FooClassWithBarMethod.private_method_defined?(:duck)
-    end
+    assert place.respond_to?(:street, true) # Asking for private method
+    assert place.respond_to?(:city, true)
   end
 
-  def test_alias_method_chain_preserves_protected_method_status
-    assert_deprecated(/alias_method_chain/) do
-      FooClassWithBarMethod.class_eval do
-        def duck; 'duck' end
-        include BarMethodAliaser
-        protected :duck
-        alias_method_chain :duck, :orange
+  def test_private_delegate_prefixed
+    location = Class.new do
+      def initialize(place)
+        @place = place
       end
 
-      assert_raise NoMethodError do
-        @instance.duck
-      end
-
-      assert_equal 'duck_with_orange', @instance.instance_eval { duck }
-      assert FooClassWithBarMethod.protected_method_defined?(:duck)
+      private(*delegate(:street, :city, to: :@place, prefix: :the))
     end
-  end
 
-  def test_alias_method_chain_preserves_public_method_status
-    assert_deprecated(/alias_method_chain/) do
-      FooClassWithBarMethod.class_eval do
-        def duck; 'duck' end
-        include BarMethodAliaser
-        public :duck
-        alias_method_chain :duck, :orange
-      end
+    place = location.new(Somewhere.new("Such street", "Sad city"))
 
-      assert_equal 'duck_with_orange', @instance.duck
-      assert FooClassWithBarMethod.public_method_defined?(:duck)
-    end
-  end
+    assert_not place.respond_to?(:street)
+    assert_not place.respond_to?(:city)
 
-  def test_delegate_with_case
-    event = Event.new(Tester.new)
-    assert_equal 1, event.foo
+    assert_not place.respond_to?(:the_street)
+    assert place.respond_to?(:the_street, true)
+    assert_not place.respond_to?(:the_city)
+    assert place.respond_to?(:the_city, true)
   end
 end
diff --git a/activesupport/test/core_ext/name_error_test.rb b/activesupport/test/core_ext/name_error_test.rb
index 7525f80cf0..d1dace3713 100644
--- a/activesupport/test/core_ext/name_error_test.rb
+++ b/activesupport/test/core_ext/name_error_test.rb
@@ -1,5 +1,7 @@
-require 'abstract_unit'
-require 'active_support/core_ext/name_error'
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "active_support/core_ext/name_error"
 
 class NameErrorTest < ActiveSupport::TestCase
   def test_name_error_should_set_missing_name
diff --git a/activesupport/test/core_ext/numeric_ext_test.rb b/activesupport/test/core_ext/numeric_ext_test.rb
index 69c30a8a9e..4b9073da54 100644
--- a/activesupport/test/core_ext/numeric_ext_test.rb
+++ b/activesupport/test/core_ext/numeric_ext_test.rb
@@ -1,18 +1,20 @@
-require 'abstract_unit'
-require 'active_support/time'
-require 'active_support/core_ext/numeric'
-require 'active_support/core_ext/integer'
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "active_support/time"
+require "active_support/core_ext/numeric"
+require "active_support/core_ext/integer"
 
 class NumericExtTimeAndDateTimeTest < ActiveSupport::TestCase
   def setup
-    @now = Time.local(2005,2,10,15,30,45)
-    @dtnow = DateTime.civil(2005,2,10,15,30,45)
+    @now = Time.local(2005, 2, 10, 15, 30, 45)
+    @dtnow = DateTime.civil(2005, 2, 10, 15, 30, 45)
     @seconds = {
       1.minute   => 60,
       10.minutes => 600,
       1.hour + 15.minutes => 4500,
       2.days + 4.hours + 30.minutes => 189000,
-      5.years + 1.month + 1.fortnight => 161589600
+      5.years + 1.month + 1.fortnight => 161624106
     }
   end
 
@@ -23,53 +25,53 @@ class NumericExtTimeAndDateTimeTest < ActiveSupport::TestCase
   end
 
   def test_irregular_durations
-    assert_equal @now.advance(:days => 3000), 3000.days.since(@now)
-    assert_equal @now.advance(:months => 1), 1.month.since(@now)
-    assert_equal @now.advance(:months => -1), 1.month.until(@now)
-    assert_equal @now.advance(:years => 20), 20.years.since(@now)
-    assert_equal @dtnow.advance(:days => 3000), 3000.days.since(@dtnow)
-    assert_equal @dtnow.advance(:months => 1), 1.month.since(@dtnow)
-    assert_equal @dtnow.advance(:months => -1), 1.month.until(@dtnow)
-    assert_equal @dtnow.advance(:years => 20), 20.years.since(@dtnow)
+    assert_equal @now.advance(days: 3000), 3000.days.since(@now)
+    assert_equal @now.advance(months: 1), 1.month.since(@now)
+    assert_equal @now.advance(months: -1), 1.month.until(@now)
+    assert_equal @now.advance(years: 20), 20.years.since(@now)
+    assert_equal @dtnow.advance(days: 3000), 3000.days.since(@dtnow)
+    assert_equal @dtnow.advance(months: 1), 1.month.since(@dtnow)
+    assert_equal @dtnow.advance(months: -1), 1.month.until(@dtnow)
+    assert_equal @dtnow.advance(years: 20), 20.years.since(@dtnow)
   end
 
   def test_duration_addition
-    assert_equal @now.advance(:days => 1).advance(:months => 1), (1.day + 1.month).since(@now)
-    assert_equal @now.advance(:days => 7), (1.week + 5.seconds - 5.seconds).since(@now)
-    assert_equal @now.advance(:years => 2), (4.years - 2.years).since(@now)
-    assert_equal @dtnow.advance(:days => 1).advance(:months => 1), (1.day + 1.month).since(@dtnow)
-    assert_equal @dtnow.advance(:days => 7), (1.week + 5.seconds - 5.seconds).since(@dtnow)
-    assert_equal @dtnow.advance(:years => 2), (4.years - 2.years).since(@dtnow)
+    assert_equal @now.advance(days: 1).advance(months: 1), (1.day + 1.month).since(@now)
+    assert_equal @now.advance(days: 7), (1.week + 5.seconds - 5.seconds).since(@now)
+    assert_equal @now.advance(years: 2), (4.years - 2.years).since(@now)
+    assert_equal @dtnow.advance(days: 1).advance(months: 1), (1.day + 1.month).since(@dtnow)
+    assert_equal @dtnow.advance(days: 7), (1.week + 5.seconds - 5.seconds).since(@dtnow)
+    assert_equal @dtnow.advance(years: 2), (4.years - 2.years).since(@dtnow)
   end
 
   def test_time_plus_duration
     assert_equal @now + 8, @now + 8.seconds
     assert_equal @now + 22.9, @now + 22.9.seconds
-    assert_equal @now.advance(:days => 15), @now + 15.days
-    assert_equal @now.advance(:months => 1), @now + 1.month
+    assert_equal @now.advance(days: 15), @now + 15.days
+    assert_equal @now.advance(months: 1), @now + 1.month
     assert_equal @dtnow.since(8), @dtnow + 8.seconds
     assert_equal @dtnow.since(22.9), @dtnow + 22.9.seconds
-    assert_equal @dtnow.advance(:days => 15), @dtnow + 15.days
-    assert_equal @dtnow.advance(:months => 1), @dtnow + 1.month
+    assert_equal @dtnow.advance(days: 15), @dtnow + 15.days
+    assert_equal @dtnow.advance(months: 1), @dtnow + 1.month
   end
 
   def test_chaining_duration_operations
-    assert_equal @now.advance(:days => 2).advance(:months => -3), @now + 2.days - 3.months
-    assert_equal @now.advance(:days => 1).advance(:months => 2), @now + 1.day + 2.months
-    assert_equal @dtnow.advance(:days => 2).advance(:months => -3), @dtnow + 2.days - 3.months
-    assert_equal @dtnow.advance(:days => 1).advance(:months => 2), @dtnow + 1.day + 2.months
+    assert_equal @now.advance(days: 2).advance(months: -3), @now + 2.days - 3.months
+    assert_equal @now.advance(days: 1).advance(months: 2), @now + 1.day + 2.months
+    assert_equal @dtnow.advance(days: 2).advance(months: -3), @dtnow + 2.days - 3.months
+    assert_equal @dtnow.advance(days: 1).advance(months: 2), @dtnow + 1.day + 2.months
   end
 
   def test_duration_after_conversion_is_no_longer_accurate
-    assert_equal 30.days.to_i.seconds.since(@now), 1.month.to_i.seconds.since(@now)
-    assert_equal 365.25.days.to_f.seconds.since(@now), 1.year.to_f.seconds.since(@now)
-    assert_equal 30.days.to_i.seconds.since(@dtnow), 1.month.to_i.seconds.since(@dtnow)
-    assert_equal 365.25.days.to_f.seconds.since(@dtnow), 1.year.to_f.seconds.since(@dtnow)
+    assert_equal (1.year / 12).to_i.seconds.since(@now), 1.month.to_i.seconds.since(@now)
+    assert_equal 365.2425.days.to_f.seconds.since(@now), 1.year.to_f.seconds.since(@now)
+    assert_equal (1.year / 12).to_i.seconds.since(@dtnow), 1.month.to_i.seconds.since(@dtnow)
+    assert_equal 365.2425.days.to_f.seconds.since(@dtnow), 1.year.to_f.seconds.since(@dtnow)
   end
 
   def test_add_one_year_to_leap_day
-    assert_equal Time.utc(2005,2,28,15,15,10), Time.utc(2004,2,29,15,15,10) + 1.year
-    assert_equal DateTime.civil(2005,2,28,15,15,10), DateTime.civil(2004,2,29,15,15,10) + 1.year
+    assert_equal Time.utc(2005, 2, 28, 15, 15, 10), Time.utc(2004, 2, 29, 15, 15, 10) + 1.year
+    assert_equal DateTime.civil(2005, 2, 28, 15, 15, 10), DateTime.civil(2004, 2, 29, 15, 15, 10) + 1.year
   end
 end
 
@@ -83,16 +85,16 @@ class NumericExtDateTest < ActiveSupport::TestCase
     assert_equal @today >> 1, @today + 1.month
     assert_equal @today.to_time.since(1), @today + 1.second
     assert_equal @today.to_time.since(60), @today + 1.minute
-    assert_equal @today.to_time.since(60*60), @today + 1.hour
+    assert_equal @today.to_time.since(60 * 60), @today + 1.hour
   end
 
   def test_chaining_duration_operations
-    assert_equal @today.advance(:days => 2).advance(:months => -3), @today + 2.days - 3.months
-    assert_equal @today.advance(:days => 1).advance(:months => 2), @today + 1.day + 2.months
+    assert_equal @today.advance(days: 2).advance(months: -3), @today + 2.days - 3.months
+    assert_equal @today.advance(days: 1).advance(months: 2), @today + 1.day + 2.months
   end
 
   def test_add_one_year_to_leap_day
-    assert_equal Date.new(2005,2,28), Date.new(2004,2,29) + 1.year
+    assert_equal Date.new(2005, 2, 28), Date.new(2004, 2, 29) + 1.year
   end
 end
 
@@ -102,12 +104,12 @@ class NumericExtSizeTest < ActiveSupport::TestCase
     assert_equal 1024.kilobytes, 1.megabyte
     assert_equal 3584.0.kilobytes, 3.5.megabytes
     assert_equal 3584.0.megabytes, 3.5.gigabytes
-    assert_equal 1.kilobyte ** 4, 1.terabyte
+    assert_equal 1.kilobyte**4, 1.terabyte
     assert_equal 1024.kilobytes + 2.megabytes, 3.megabytes
     assert_equal 2.gigabytes / 4, 512.megabytes
     assert_equal 256.megabytes * 20 + 5.gigabytes, 10.gigabytes
-    assert_equal 1.kilobyte ** 5, 1.petabyte
-    assert_equal 1.kilobyte ** 6, 1.exabyte
+    assert_equal 1.kilobyte**5, 1.petabyte
+    assert_equal 1.kilobyte**6, 1.exabyte
   end
 
   def test_units_as_bytes_independently
@@ -154,53 +156,52 @@ class NumericExtFormattingTest < ActiveSupport::TestCase
   def test_to_s__phone
     assert_equal("555-1234", 5551234.to_s(:phone))
     assert_equal("800-555-1212", 8005551212.to_s(:phone))
-    assert_equal("(800) 555-1212", 8005551212.to_s(:phone, :area_code => true))
-    assert_equal("800 555 1212", 8005551212.to_s(:phone, :delimiter => " "))
-    assert_equal("(800) 555-1212 x 123", 8005551212.to_s(:phone, :area_code => true, :extension => 123))
-    assert_equal("800-555-1212", 8005551212.to_s(:phone, :extension => "  "))
-    assert_equal("555.1212", 5551212.to_s(:phone, :delimiter => '.'))
-    assert_equal("+1-800-555-1212", 8005551212.to_s(:phone, :country_code => 1))
-    assert_equal("+18005551212", 8005551212.to_s(:phone, :country_code => 1, :delimiter => ''))
+    assert_equal("(800) 555-1212", 8005551212.to_s(:phone, area_code: true))
+    assert_equal("800 555 1212", 8005551212.to_s(:phone, delimiter: " "))
+    assert_equal("(800) 555-1212 x 123", 8005551212.to_s(:phone, area_code: true, extension: 123))
+    assert_equal("800-555-1212", 8005551212.to_s(:phone, extension: "  "))
+    assert_equal("555.1212", 5551212.to_s(:phone, delimiter: "."))
+    assert_equal("+1-800-555-1212", 8005551212.to_s(:phone, country_code: 1))
+    assert_equal("+18005551212", 8005551212.to_s(:phone, country_code: 1, delimiter: ""))
     assert_equal("22-555-1212", 225551212.to_s(:phone))
-    assert_equal("+45-22-555-1212", 225551212.to_s(:phone, :country_code => 45))
+    assert_equal("+45-22-555-1212", 225551212.to_s(:phone, country_code: 45))
   end
 
   def test_to_s__currency
     assert_equal("$1,234,567,890.50", 1234567890.50.to_s(:currency))
     assert_equal("$1,234,567,890.51", 1234567890.506.to_s(:currency))
     assert_equal("-$1,234,567,890.50", -1234567890.50.to_s(:currency))
-    assert_equal("-$ 1,234,567,890.50", -1234567890.50.to_s(:currency, :format => "%u %n"))
-    assert_equal("($1,234,567,890.50)", -1234567890.50.to_s(:currency, :negative_format => "(%u%n)"))
-    assert_equal("$1,234,567,892", 1234567891.50.to_s(:currency, :precision => 0))
-    assert_equal("$1,234,567,890.5", 1234567890.50.to_s(:currency, :precision => 1))
-    assert_equal("&pound;1234567890,50", 1234567890.50.to_s(:currency, :unit => "&pound;", :separator => ",", :delimiter => ""))
+    assert_equal("-$ 1,234,567,890.50", -1234567890.50.to_s(:currency, format: "%u %n"))
+    assert_equal("($1,234,567,890.50)", -1234567890.50.to_s(:currency, negative_format: "(%u%n)"))
+    assert_equal("$1,234,567,892", 1234567891.50.to_s(:currency, precision: 0))
+    assert_equal("$1,234,567,890.5", 1234567890.50.to_s(:currency, precision: 1))
+    assert_equal("&pound;1234567890,50", 1234567890.50.to_s(:currency, unit: "&pound;", separator: ",", delimiter: ""))
   end
 
-
   def test_to_s__rounded
     assert_equal("-111.235", -111.2346.to_s(:rounded))
     assert_equal("111.235", 111.2346.to_s(:rounded))
-    assert_equal("31.83", 31.825.to_s(:rounded, :precision => 2))
-    assert_equal("111.23", 111.2346.to_s(:rounded, :precision => 2))
-    assert_equal("111.00", 111.to_s(:rounded, :precision => 2))
-    assert_equal("3268", (32.6751 * 100.00).to_s(:rounded, :precision => 0))
-    assert_equal("112", 111.50.to_s(:rounded, :precision => 0))
-    assert_equal("1234567892", 1234567891.50.to_s(:rounded, :precision => 0))
-    assert_equal("0", 0.to_s(:rounded, :precision => 0))
-    assert_equal("0.00100", 0.001.to_s(:rounded, :precision => 5))
-    assert_equal("0.001", 0.00111.to_s(:rounded, :precision => 3))
-    assert_equal("10.00", 9.995.to_s(:rounded, :precision => 2))
-    assert_equal("11.00", 10.995.to_s(:rounded, :precision => 2))
-    assert_equal("0.00", -0.001.to_s(:rounded, :precision => 2))
+    assert_equal("31.83", 31.825.to_s(:rounded, precision: 2))
+    assert_equal("111.23", 111.2346.to_s(:rounded, precision: 2))
+    assert_equal("111.00", 111.to_s(:rounded, precision: 2))
+    assert_equal("3268", (32.6751 * 100.00).to_s(:rounded, precision: 0))
+    assert_equal("112", 111.50.to_s(:rounded, precision: 0))
+    assert_equal("1234567892", 1234567891.50.to_s(:rounded, precision: 0))
+    assert_equal("0", 0.to_s(:rounded, precision: 0))
+    assert_equal("0.00100", 0.001.to_s(:rounded, precision: 5))
+    assert_equal("0.001", 0.00111.to_s(:rounded, precision: 3))
+    assert_equal("10.00", 9.995.to_s(:rounded, precision: 2))
+    assert_equal("11.00", 10.995.to_s(:rounded, precision: 2))
+    assert_equal("0.00", -0.001.to_s(:rounded, precision: 2))
   end
 
   def test_to_s__percentage
     assert_equal("100.000%", 100.to_s(:percentage))
-    assert_equal("100%", 100.to_s(:percentage, :precision => 0))
-    assert_equal("302.06%", 302.0574.to_s(:percentage, :precision => 2))
-    assert_equal("123.4%", 123.400.to_s(:percentage, :precision => 3, :strip_insignificant_zeros => true))
-    assert_equal("1.000,000%", 1000.to_s(:percentage, :delimiter => '.', :separator => ','))
-    assert_equal("1000.000  %", 1000.to_s(:percentage, :format => "%n  %"))
+    assert_equal("100%", 100.to_s(:percentage, precision: 0))
+    assert_equal("302.06%", 302.0574.to_s(:percentage, precision: 2))
+    assert_equal("123.4%", 123.400.to_s(:percentage, precision: 3, strip_insignificant_zeros: true))
+    assert_equal("1.000,000%", 1000.to_s(:percentage, delimiter: ".", separator: ","))
+    assert_equal("1000.000  %", 1000.to_s(:percentage, format: "%n  %"))
   end
 
   def test_to_s__delimited
@@ -216,207 +217,189 @@ class NumericExtFormattingTest < ActiveSupport::TestCase
   end
 
   def test_to_s__delimited__with_options_hash
-    assert_equal '12 345 678', 12345678.to_s(:delimited, :delimiter => ' ')
-    assert_equal '12,345,678-05', 12345678.05.to_s(:delimited, :separator => '-')
-    assert_equal '12.345.678,05', 12345678.05.to_s(:delimited, :separator => ',', :delimiter => '.')
-    assert_equal '12.345.678,05', 12345678.05.to_s(:delimited, :delimiter => '.', :separator => ',')
+    assert_equal "12 345 678", 12345678.to_s(:delimited, delimiter: " ")
+    assert_equal "12,345,678-05", 12345678.05.to_s(:delimited, separator: "-")
+    assert_equal "12.345.678,05", 12345678.05.to_s(:delimited, separator: ",", delimiter: ".")
+    assert_equal "12.345.678,05", 12345678.05.to_s(:delimited, delimiter: ".", separator: ",")
   end
 
-
   def test_to_s__rounded_with_custom_delimiter_and_separator
-    assert_equal '31,83',       31.825.to_s(:rounded, :precision => 2, :separator => ',')
-    assert_equal '1.231,83',    1231.825.to_s(:rounded, :precision => 2, :separator => ',', :delimiter => '.')
+    assert_equal "31,83",       31.825.to_s(:rounded, precision: 2, separator: ",")
+    assert_equal "1.231,83",    1231.825.to_s(:rounded, precision: 2, separator: ",", delimiter: ".")
   end
 
   def test_to_s__rounded__with_significant_digits
-    assert_equal "124000", 123987.to_s(:rounded, :precision => 3, :significant => true)
-    assert_equal "120000000", 123987876.to_s(:rounded, :precision => 2, :significant => true )
-    assert_equal "9775", 9775.to_s(:rounded, :precision => 4, :significant => true )
-    assert_equal "5.4", 5.3923.to_s(:rounded, :precision => 2, :significant => true )
-    assert_equal "5", 5.3923.to_s(:rounded, :precision => 1, :significant => true )
-    assert_equal "1", 1.232.to_s(:rounded, :precision => 1, :significant => true )
-    assert_equal "7", 7.to_s(:rounded, :precision => 1, :significant => true )
-    assert_equal "1", 1.to_s(:rounded, :precision => 1, :significant => true )
-    assert_equal "53", 52.7923.to_s(:rounded, :precision => 2, :significant => true )
-    assert_equal "9775.00", 9775.to_s(:rounded, :precision => 6, :significant => true )
-    assert_equal "5.392900", 5.3929.to_s(:rounded, :precision => 7, :significant => true )
-    assert_equal "0.0", 0.to_s(:rounded, :precision => 2, :significant => true )
-    assert_equal "0", 0.to_s(:rounded, :precision => 1, :significant => true )
-    assert_equal "0.0001", 0.0001.to_s(:rounded, :precision => 1, :significant => true )
-    assert_equal "0.000100", 0.0001.to_s(:rounded, :precision => 3, :significant => true )
-    assert_equal "0.0001", 0.0001111.to_s(:rounded, :precision => 1, :significant => true )
-    assert_equal "10.0", 9.995.to_s(:rounded, :precision => 3, :significant => true)
-    assert_equal "9.99", 9.994.to_s(:rounded, :precision => 3, :significant => true)
-    assert_equal "11.0", 10.995.to_s(:rounded, :precision => 3, :significant => true)
+    assert_equal "124000", 123987.to_s(:rounded, precision: 3, significant: true)
+    assert_equal "120000000", 123987876.to_s(:rounded, precision: 2, significant: true)
+    assert_equal "9775", 9775.to_s(:rounded, precision: 4, significant: true)
+    assert_equal "5.4", 5.3923.to_s(:rounded, precision: 2, significant: true)
+    assert_equal "5", 5.3923.to_s(:rounded, precision: 1, significant: true)
+    assert_equal "1", 1.232.to_s(:rounded, precision: 1, significant: true)
+    assert_equal "7", 7.to_s(:rounded, precision: 1, significant: true)
+    assert_equal "1", 1.to_s(:rounded, precision: 1, significant: true)
+    assert_equal "53", 52.7923.to_s(:rounded, precision: 2, significant: true)
+    assert_equal "9775.00", 9775.to_s(:rounded, precision: 6, significant: true)
+    assert_equal "5.392900", 5.3929.to_s(:rounded, precision: 7, significant: true)
+    assert_equal "0.0", 0.to_s(:rounded, precision: 2, significant: true)
+    assert_equal "0", 0.to_s(:rounded, precision: 1, significant: true)
+    assert_equal "0.0001", 0.0001.to_s(:rounded, precision: 1, significant: true)
+    assert_equal "0.000100", 0.0001.to_s(:rounded, precision: 3, significant: true)
+    assert_equal "0.0001", 0.0001111.to_s(:rounded, precision: 1, significant: true)
+    assert_equal "10.0", 9.995.to_s(:rounded, precision: 3, significant: true)
+    assert_equal "9.99", 9.994.to_s(:rounded, precision: 3, significant: true)
+    assert_equal "11.0", 10.995.to_s(:rounded, precision: 3, significant: true)
   end
 
   def test_to_s__rounded__with_strip_insignificant_zeros
-    assert_equal "9775.43", 9775.43.to_s(:rounded, :precision => 4, :strip_insignificant_zeros => true )
-    assert_equal "9775.2", 9775.2.to_s(:rounded, :precision => 6, :significant => true, :strip_insignificant_zeros => true )
-    assert_equal "0", 0.to_s(:rounded, :precision => 6, :significant => true, :strip_insignificant_zeros => true )
+    assert_equal "9775.43", 9775.43.to_s(:rounded, precision: 4, strip_insignificant_zeros: true)
+    assert_equal "9775.2", 9775.2.to_s(:rounded, precision: 6, significant: true, strip_insignificant_zeros: true)
+    assert_equal "0", 0.to_s(:rounded, precision: 6, significant: true, strip_insignificant_zeros: true)
   end
 
   def test_to_s__rounded__with_significant_true_and_zero_precision
     # Zero precision with significant is a mistake (would always return zero),
     # so we treat it as if significant was false (increases backwards compatibility for number_to_human_size)
-    assert_equal "124", 123.987.to_s(:rounded, :precision => 0, :significant => true)
-    assert_equal "12", 12.to_s(:rounded, :precision => 0, :significant => true )
+    assert_equal "124", 123.987.to_s(:rounded, precision: 0, significant: true)
+    assert_equal "12", 12.to_s(:rounded, precision: 0, significant: true)
   end
 
   def test_to_s__human_size
-    assert_equal '0 Bytes',   0.to_s(:human_size)
-    assert_equal '1 Byte',    1.to_s(:human_size)
-    assert_equal '3 Bytes',   3.14159265.to_s(:human_size)
-    assert_equal '123 Bytes', 123.0.to_s(:human_size)
-    assert_equal '123 Bytes', 123.to_s(:human_size)
-    assert_equal '1.21 KB',   1234.to_s(:human_size)
-    assert_equal '12.1 KB',   12345.to_s(:human_size)
-    assert_equal '1.18 MB',   1234567.to_s(:human_size)
-    assert_equal '1.15 GB',   1234567890.to_s(:human_size)
-    assert_equal '1.12 TB',   1234567890123.to_s(:human_size)
-    assert_equal '1.1 PB',    1234567890123456.to_s(:human_size)
-    assert_equal '1.07 EB',   1234567890123456789.to_s(:human_size)
-    assert_equal '1030 EB',   exabytes(1026).to_s(:human_size)
-    assert_equal '444 KB',    kilobytes(444).to_s(:human_size)
-    assert_equal '1020 MB',   megabytes(1023).to_s(:human_size)
-    assert_equal '3 TB',      terabytes(3).to_s(:human_size)
-    assert_equal '1.2 MB',    1234567.to_s(:human_size, :precision => 2)
-    assert_equal '3 Bytes',   3.14159265.to_s(:human_size, :precision => 4)
-    assert_equal '1 KB',      kilobytes(1.0123).to_s(:human_size, :precision => 2)
-    assert_equal '1.01 KB',   kilobytes(1.0100).to_s(:human_size, :precision => 4)
-    assert_equal '10 KB',     kilobytes(10.000).to_s(:human_size, :precision => 4)
-    assert_equal '1 Byte',    1.1.to_s(:human_size)
-    assert_equal '10 Bytes',  10.to_s(:human_size)
-  end
-
-  def test_to_s__human_size_with_si_prefix
-    assert_deprecated do
-      assert_equal '3 Bytes',    3.14159265.to_s(:human_size, :prefix => :si)
-      assert_equal '123 Bytes',  123.0.to_s(:human_size, :prefix => :si)
-      assert_equal '123 Bytes',  123.to_s(:human_size, :prefix => :si)
-      assert_equal '1.23 KB',    1234.to_s(:human_size, :prefix => :si)
-      assert_equal '12.3 KB',    12345.to_s(:human_size, :prefix => :si)
-      assert_equal '1.23 MB',    1234567.to_s(:human_size, :prefix => :si)
-      assert_equal '1.23 GB',    1234567890.to_s(:human_size, :prefix => :si)
-      assert_equal '1.23 TB',    1234567890123.to_s(:human_size, :prefix => :si)
-      assert_equal '1.23 PB',    1234567890123456.to_s(:human_size, :prefix => :si)
-      assert_equal '1.23 EB',    1234567890123456789.to_s(:human_size, :prefix => :si)
-    end
+    assert_equal "0 Bytes",   0.to_s(:human_size)
+    assert_equal "1 Byte",    1.to_s(:human_size)
+    assert_equal "3 Bytes",   3.14159265.to_s(:human_size)
+    assert_equal "123 Bytes", 123.0.to_s(:human_size)
+    assert_equal "123 Bytes", 123.to_s(:human_size)
+    assert_equal "1.21 KB",   1234.to_s(:human_size)
+    assert_equal "12.1 KB",   12345.to_s(:human_size)
+    assert_equal "1.18 MB",   1234567.to_s(:human_size)
+    assert_equal "1.15 GB",   1234567890.to_s(:human_size)
+    assert_equal "1.12 TB",   1234567890123.to_s(:human_size)
+    assert_equal "1.1 PB",    1234567890123456.to_s(:human_size)
+    assert_equal "1.07 EB",   1234567890123456789.to_s(:human_size)
+    assert_equal "1030 EB",   exabytes(1026).to_s(:human_size)
+    assert_equal "444 KB",    kilobytes(444).to_s(:human_size)
+    assert_equal "1020 MB",   megabytes(1023).to_s(:human_size)
+    assert_equal "3 TB",      terabytes(3).to_s(:human_size)
+    assert_equal "1.2 MB",    1234567.to_s(:human_size, precision: 2)
+    assert_equal "3 Bytes",   3.14159265.to_s(:human_size, precision: 4)
+    assert_equal "1 KB",      kilobytes(1.0123).to_s(:human_size, precision: 2)
+    assert_equal "1.01 KB",   kilobytes(1.0100).to_s(:human_size, precision: 4)
+    assert_equal "10 KB",     kilobytes(10.000).to_s(:human_size, precision: 4)
+    assert_equal "1 Byte",    1.1.to_s(:human_size)
+    assert_equal "10 Bytes",  10.to_s(:human_size)
   end
 
   def test_to_s__human_size_with_options_hash
-    assert_equal '1.2 MB',   1234567.to_s(:human_size, :precision => 2)
-    assert_equal '3 Bytes',  3.14159265.to_s(:human_size, :precision => 4)
-    assert_equal '1 KB',     kilobytes(1.0123).to_s(:human_size, :precision => 2)
-    assert_equal '1.01 KB',  kilobytes(1.0100).to_s(:human_size, :precision => 4)
-    assert_equal '10 KB',    kilobytes(10.000).to_s(:human_size, :precision => 4)
-    assert_equal '1 TB',     1234567890123.to_s(:human_size, :precision => 1)
-    assert_equal '500 MB',   524288000.to_s(:human_size, :precision=>3)
-    assert_equal '10 MB',    9961472.to_s(:human_size, :precision=>0)
-    assert_equal '40 KB',    41010.to_s(:human_size, :precision => 1)
-    assert_equal '40 KB',    41100.to_s(:human_size, :precision => 2)
-    assert_equal '1.0 KB',   kilobytes(1.0123).to_s(:human_size, :precision => 2, :strip_insignificant_zeros => false)
-    assert_equal '1.012 KB', kilobytes(1.0123).to_s(:human_size, :precision => 3, :significant => false)
-    assert_equal '1 KB',     kilobytes(1.0123).to_s(:human_size, :precision => 0, :significant => true) #ignores significant it precision is 0
+    assert_equal "1.2 MB",   1234567.to_s(:human_size, precision: 2)
+    assert_equal "3 Bytes",  3.14159265.to_s(:human_size, precision: 4)
+    assert_equal "1 KB",     kilobytes(1.0123).to_s(:human_size, precision: 2)
+    assert_equal "1.01 KB",  kilobytes(1.0100).to_s(:human_size, precision: 4)
+    assert_equal "10 KB",    kilobytes(10.000).to_s(:human_size, precision: 4)
+    assert_equal "1 TB",     1234567890123.to_s(:human_size, precision: 1)
+    assert_equal "500 MB",   524288000.to_s(:human_size, precision: 3)
+    assert_equal "10 MB",    9961472.to_s(:human_size, precision: 0)
+    assert_equal "40 KB",    41010.to_s(:human_size, precision: 1)
+    assert_equal "40 KB",    41100.to_s(:human_size, precision: 2)
+    assert_equal "1.0 KB",   kilobytes(1.0123).to_s(:human_size, precision: 2, strip_insignificant_zeros: false)
+    assert_equal "1.012 KB", kilobytes(1.0123).to_s(:human_size, precision: 3, significant: false)
+    assert_equal "1 KB",     kilobytes(1.0123).to_s(:human_size, precision: 0, significant: true) # ignores significant it precision is 0
   end
 
   def test_to_s__human_size_with_custom_delimiter_and_separator
-    assert_equal '1,01 KB',     kilobytes(1.0123).to_s(:human_size, :precision => 3, :separator => ',')
-    assert_equal '1,01 KB',     kilobytes(1.0100).to_s(:human_size, :precision => 4, :separator => ',')
-    assert_equal '1.000,1 TB',  terabytes(1000.1).to_s(:human_size, :precision => 5, :delimiter => '.', :separator => ',')
+    assert_equal "1,01 KB",     kilobytes(1.0123).to_s(:human_size, precision: 3, separator: ",")
+    assert_equal "1,01 KB",     kilobytes(1.0100).to_s(:human_size, precision: 4, separator: ",")
+    assert_equal "1.000,1 TB",  terabytes(1000.1).to_s(:human_size, precision: 5, delimiter: ".", separator: ",")
   end
 
   def test_number_to_human
-    assert_equal '-123', -123.to_s(:human)
-    assert_equal '-0.5', -0.5.to_s(:human)
-    assert_equal '0',   0.to_s(:human)
-    assert_equal '0.5', 0.5.to_s(:human)
-    assert_equal '123', 123.to_s(:human)
-    assert_equal '1.23 Thousand', 1234.to_s(:human)
-    assert_equal '12.3 Thousand', 12345.to_s(:human)
-    assert_equal '1.23 Million', 1234567.to_s(:human)
-    assert_equal '1.23 Billion', 1234567890.to_s(:human)
-    assert_equal '1.23 Trillion', 1234567890123.to_s(:human)
-    assert_equal '1.23 Quadrillion', 1234567890123456.to_s(:human)
-    assert_equal '1230 Quadrillion', 1234567890123456789.to_s(:human)
-    assert_equal '490 Thousand', 489939.to_s(:human, :precision => 2)
-    assert_equal '489.9 Thousand', 489939.to_s(:human, :precision => 4)
-    assert_equal '489 Thousand', 489000.to_s(:human, :precision => 4)
-    assert_equal '489.0 Thousand', 489000.to_s(:human, :precision => 4, :strip_insignificant_zeros => false)
-    assert_equal '1.2346 Million', 1234567.to_s(:human, :precision => 4, :significant => false)
-    assert_equal '1,2 Million', 1234567.to_s(:human, :precision => 1, :significant => false, :separator => ',')
-    assert_equal '1 Million', 1234567.to_s(:human, :precision => 0, :significant => true, :separator => ',') #significant forced to false
+    assert_equal "-123", -123.to_s(:human)
+    assert_equal "-0.5", -0.5.to_s(:human)
+    assert_equal "0",   0.to_s(:human)
+    assert_equal "0.5", 0.5.to_s(:human)
+    assert_equal "123", 123.to_s(:human)
+    assert_equal "1.23 Thousand", 1234.to_s(:human)
+    assert_equal "12.3 Thousand", 12345.to_s(:human)
+    assert_equal "1.23 Million", 1234567.to_s(:human)
+    assert_equal "1.23 Billion", 1234567890.to_s(:human)
+    assert_equal "1.23 Trillion", 1234567890123.to_s(:human)
+    assert_equal "1.23 Quadrillion", 1234567890123456.to_s(:human)
+    assert_equal "1230 Quadrillion", 1234567890123456789.to_s(:human)
+    assert_equal "490 Thousand", 489939.to_s(:human, precision: 2)
+    assert_equal "489.9 Thousand", 489939.to_s(:human, precision: 4)
+    assert_equal "489 Thousand", 489000.to_s(:human, precision: 4)
+    assert_equal "489.0 Thousand", 489000.to_s(:human, precision: 4, strip_insignificant_zeros: false)
+    assert_equal "1.2346 Million", 1234567.to_s(:human, precision: 4, significant: false)
+    assert_equal "1,2 Million", 1234567.to_s(:human, precision: 1, significant: false, separator: ",")
+    assert_equal "1 Million", 1234567.to_s(:human, precision: 0, significant: true, separator: ",") # significant forced to false
   end
 
   def test_number_to_human_with_custom_units
-    #Only integers
-    volume = {:unit => "ml", :thousand => "lt", :million => "m3"}
-    assert_equal '123 lt', 123456.to_s(:human, :units => volume)
-    assert_equal '12 ml', 12.to_s(:human, :units => volume)
-    assert_equal '1.23 m3', 1234567.to_s(:human, :units => volume)
-
-    #Including fractionals
-    distance = {:mili => "mm", :centi => "cm", :deci => "dm", :unit => "m", :ten => "dam", :hundred => "hm", :thousand => "km"}
-    assert_equal '1.23 mm', 0.00123.to_s(:human, :units => distance)
-    assert_equal '1.23 cm', 0.0123.to_s(:human, :units => distance)
-    assert_equal '1.23 dm', 0.123.to_s(:human, :units => distance)
-    assert_equal '1.23 m',  1.23.to_s(:human, :units => distance)
-    assert_equal '1.23 dam', 12.3.to_s(:human, :units => distance)
-    assert_equal '1.23 hm', 123.to_s(:human, :units => distance)
-    assert_equal '1.23 km', 1230.to_s(:human, :units => distance)
-    assert_equal '1.23 km', 1230.to_s(:human, :units => distance)
-    assert_equal '1.23 km', 1230.to_s(:human, :units => distance)
-    assert_equal '12.3 km', 12300.to_s(:human, :units => distance)
-
-    #The quantifiers don't need to be a continuous sequence
-    gangster = {:hundred => "hundred bucks", :million => "thousand quids"}
-    assert_equal '1 hundred bucks', 100.to_s(:human, :units => gangster)
-    assert_equal '25 hundred bucks', 2500.to_s(:human, :units => gangster)
-    assert_equal '25 thousand quids', 25000000.to_s(:human, :units => gangster)
-    assert_equal '12300 thousand quids', 12345000000.to_s(:human, :units => gangster)
-
-    #Spaces are stripped from the resulting string
-    assert_equal '4', 4.to_s(:human, :units => {:unit => "", :ten => 'tens '})
-    assert_equal '4.5  tens', 45.to_s(:human, :units => {:unit => "", :ten => ' tens   '})
+    # Only integers
+    volume = { unit: "ml", thousand: "lt", million: "m3" }
+    assert_equal "123 lt", 123456.to_s(:human, units: volume)
+    assert_equal "12 ml", 12.to_s(:human, units: volume)
+    assert_equal "1.23 m3", 1234567.to_s(:human, units: volume)
+
+    # Including fractionals
+    distance = { mili: "mm", centi: "cm", deci: "dm", unit: "m", ten: "dam", hundred: "hm", thousand: "km" }
+    assert_equal "1.23 mm", 0.00123.to_s(:human, units: distance)
+    assert_equal "1.23 cm", 0.0123.to_s(:human, units: distance)
+    assert_equal "1.23 dm", 0.123.to_s(:human, units: distance)
+    assert_equal "1.23 m",  1.23.to_s(:human, units: distance)
+    assert_equal "1.23 dam", 12.3.to_s(:human, units: distance)
+    assert_equal "1.23 hm", 123.to_s(:human, units: distance)
+    assert_equal "1.23 km", 1230.to_s(:human, units: distance)
+    assert_equal "1.23 km", 1230.to_s(:human, units: distance)
+    assert_equal "1.23 km", 1230.to_s(:human, units: distance)
+    assert_equal "12.3 km", 12300.to_s(:human, units: distance)
+
+    # The quantifiers don't need to be a continuous sequence
+    gangster = { hundred: "hundred bucks", million: "thousand quids" }
+    assert_equal "1 hundred bucks", 100.to_s(:human, units: gangster)
+    assert_equal "25 hundred bucks", 2500.to_s(:human, units: gangster)
+    assert_equal "25 thousand quids", 25000000.to_s(:human, units: gangster)
+    assert_equal "12300 thousand quids", 12345000000.to_s(:human, units: gangster)
+
+    # Spaces are stripped from the resulting string
+    assert_equal "4", 4.to_s(:human, units: { unit: "", ten: "tens " })
+    assert_equal "4.5  tens", 45.to_s(:human, units: { unit: "", ten: " tens   " })
   end
 
   def test_number_to_human_with_custom_format
-    assert_equal '123 times Thousand', 123456.to_s(:human, :format => "%n times %u")
-    volume = {:unit => "ml", :thousand => "lt", :million => "m3"}
-    assert_equal '123.lt', 123456.to_s(:human, :units => volume, :format => "%n.%u")
+    assert_equal "123 times Thousand", 123456.to_s(:human, format: "%n times %u")
+    volume = { unit: "ml", thousand: "lt", million: "m3" }
+    assert_equal "123.lt", 123456.to_s(:human, units: volume, format: "%n.%u")
   end
 
   def test_to_s__injected_on_proper_types
-    assert_equal '1.23 Thousand', 1230.to_s(:human)
-    assert_equal '1.23 Thousand', Float(1230).to_s(:human)
-    assert_equal '100000 Quadrillion', (100**10).to_s(:human)
-    assert_equal '1 Million', BigDecimal("1000010").to_s(:human)
-  end
-
-  def test_to_formatted_s_is_deprecated
-    assert_deprecated do
-      5551234.to_formatted_s(:phone)
-    end
+    assert_equal "1.23 Thousand", 1230.to_s(:human)
+    assert_equal "1.23 Thousand", Float(1230).to_s(:human)
+    assert_equal "100000 Quadrillion", (100**10).to_s(:human)
+    assert_equal "1 Million", BigDecimal("1000010").to_s(:human)
   end
 
   def test_to_s_with_invalid_formatter
-    assert_equal '123', 123.to_s(:invalid)
-    assert_equal '2.5', 2.5.to_s(:invalid)
-    assert_equal '100000000000000000000', (100**10).to_s(:invalid)
-    assert_equal '1000010.0', BigDecimal("1000010").to_s(:invalid)
+    assert_equal "123", 123.to_s(:invalid)
+    assert_equal "2.5", 2.5.to_s(:invalid)
+    assert_equal "100000000000000000000", (100**10).to_s(:invalid)
+    assert_equal "1000010.0", BigDecimal("1000010").to_s(:invalid)
   end
 
   def test_default_to_s
-    assert_equal '123', 123.to_s
-    assert_equal '1111011', 123.to_s(2)
+    assert_equal "123", 123.to_s
+    assert_equal "1111011", 123.to_s(2)
 
-    assert_equal '2.5', 2.5.to_s
+    assert_equal "2.5", 2.5.to_s
 
-    assert_equal '100000000000000000000', (100**10).to_s
-    assert_equal '1010110101111000111010111100010110101100011000100000000000000000000', (100**10).to_s(2)
+    assert_equal "100000000000000000000", (100**10).to_s
+    assert_equal "1010110101111000111010111100010110101100011000100000000000000000000", (100**10).to_s(2)
 
-    assert_equal '1000010.0', BigDecimal("1000010").to_s
-    assert_equal '10000 10.0', BigDecimal("1000010").to_s('5F')
+    assert_equal "1000010.0", BigDecimal("1000010").to_s
+    assert_equal "10000 10.0", BigDecimal("1000010").to_s("5F")
+
+    assert_raises TypeError do
+      1.to_s({})
+    end
   end
 
   def test_in_milliseconds
@@ -425,7 +408,6 @@ class NumericExtFormattingTest < ActiveSupport::TestCase
 
   # TODO: Remove positive and negative tests when we drop support to ruby < 2.3
   b = 2**64
-  b *= b until Bignum === b
 
   T_ZERO = b.coerce(0).first
   T_ONE  = b.coerce(1).first
@@ -455,8 +437,8 @@ class NumericExtFormattingTest < ActiveSupport::TestCase
     end.new
     assert_not_predicate(a, :positive?)
 
-    assert_predicate(1/2r, :positive?)
-    assert_not_predicate(-1/2r, :positive?)
+    assert_predicate(1 / 2r, :positive?)
+    assert_not_predicate(-1 / 2r, :positive?)
 
     assert_predicate(T_ONE, :positive?)
     assert_not_predicate(T_MONE, :positive?)
@@ -493,8 +475,8 @@ class NumericExtFormattingTest < ActiveSupport::TestCase
     end.new
     assert_not_predicate(a, :negative?)
 
-    assert_predicate(-1/2r, :negative?)
-    assert_not_predicate(1/2r, :negative?)
+    assert_predicate(-1 / 2r, :negative?)
+    assert_not_predicate(1 / 2r, :negative?)
 
     assert_not_predicate(T_ONE, :negative?)
     assert_predicate(T_MONE, :negative?)
diff --git a/activesupport/test/core_ext/object/acts_like_test.rb b/activesupport/test/core_ext/object/acts_like_test.rb
index e68b1d23cb..9f7b81f7fc 100644
--- a/activesupport/test/core_ext/object/acts_like_test.rb
+++ b/activesupport/test/core_ext/object/acts_like_test.rb
@@ -1,5 +1,7 @@
-require 'abstract_unit'
-require 'active_support/core_ext/object'
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "active_support/core_ext/object"
 
 class ObjectTests < ActiveSupport::TestCase
   class DuckTime
diff --git a/activesupport/test/core_ext/object/blank_test.rb b/activesupport/test/core_ext/object/blank_test.rb
index a142096993..749e59ec00 100644
--- a/activesupport/test/core_ext/object/blank_test.rb
+++ b/activesupport/test/core_ext/object/blank_test.rb
@@ -1,5 +1,7 @@
-require 'abstract_unit'
-require 'active_support/core_ext/object/blank'
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "active_support/core_ext/object/blank"
 
 class BlankTest < ActiveSupport::TestCase
   class EmptyTrue
@@ -14,8 +16,8 @@ class BlankTest < ActiveSupport::TestCase
     end
   end
 
-  BLANK = [ EmptyTrue.new, nil, false, '', '   ', "  \n\t  \r ", '　', "\u00a0", [], {} ]
-  NOT   = [ EmptyFalse.new, Object.new, true, 0, 1, 'a', [nil], { nil => 0 } ]
+  BLANK = [ EmptyTrue.new, nil, false, "", "   ", "  \n\t  \r ", "　", "\u00a0", [], {} ]
+  NOT   = [ EmptyFalse.new, Object.new, true, 0, 1, "a", [nil], { nil => 0 }, Time.now ]
 
   def test_blank
     BLANK.each { |v| assert_equal true, v.blank?,  "#{v.inspect} should be blank" }
@@ -28,7 +30,7 @@ class BlankTest < ActiveSupport::TestCase
   end
 
   def test_presence
-    BLANK.each { |v| assert_equal nil, v.presence, "#{v.inspect}.presence should return nil" }
+    BLANK.each { |v| assert_nil v.presence, "#{v.inspect}.presence should return nil" }
     NOT.each   { |v| assert_equal v,   v.presence, "#{v.inspect}.presence should return self" }
   end
 end
diff --git a/activesupport/test/core_ext/object/deep_dup_test.rb b/activesupport/test/core_ext/object/deep_dup_test.rb
index aa839201ea..2486592441 100644
--- a/activesupport/test/core_ext/object/deep_dup_test.rb
+++ b/activesupport/test/core_ext/object/deep_dup_test.rb
@@ -1,43 +1,44 @@
-require 'abstract_unit'
-require 'active_support/core_ext/object'
+# frozen_string_literal: true
 
-class DeepDupTest < ActiveSupport::TestCase
+require "abstract_unit"
+require "active_support/core_ext/object"
 
+class DeepDupTest < ActiveSupport::TestCase
   def test_array_deep_dup
     array = [1, [2, 3]]
     dup = array.deep_dup
     dup[1][2] = 4
-    assert_equal nil, array[1][2]
+    assert_nil array[1][2]
     assert_equal 4, dup[1][2]
   end
 
   def test_hash_deep_dup
-    hash = { :a => { :b => 'b' } }
+    hash = { a: { b: "b" } }
     dup = hash.deep_dup
-    dup[:a][:c] = 'c'
-    assert_equal nil, hash[:a][:c]
-    assert_equal 'c', dup[:a][:c]
+    dup[:a][:c] = "c"
+    assert_nil hash[:a][:c]
+    assert_equal "c", dup[:a][:c]
   end
 
   def test_array_deep_dup_with_hash_inside
-    array = [1, { :a => 2, :b => 3 } ]
+    array = [1, { a: 2, b: 3 } ]
     dup = array.deep_dup
     dup[1][:c] = 4
-    assert_equal nil, array[1][:c]
+    assert_nil array[1][:c]
     assert_equal 4, dup[1][:c]
   end
 
   def test_hash_deep_dup_with_array_inside
-    hash = { :a => [1, 2] }
+    hash = { a: [1, 2] }
     dup = hash.deep_dup
-    dup[:a][2] = 'c'
-    assert_equal nil, hash[:a][2]
-    assert_equal 'c', dup[:a][2]
+    dup[:a][2] = "c"
+    assert_nil hash[:a][2]
+    assert_equal "c", dup[:a][2]
   end
 
   def test_deep_dup_initialize
     zero_hash = Hash.new 0
-    hash = { :a => zero_hash }
+    hash = { a: zero_hash }
     dup = hash.deep_dup
     assert_equal 0, dup[:a][44]
   end
@@ -55,5 +56,4 @@ class DeepDupTest < ActiveSupport::TestCase
     dup = hash.deep_dup
     assert_equal 1, dup.keys.length
   end
-
 end
diff --git a/activesupport/test/core_ext/object/duplicable_test.rb b/activesupport/test/core_ext/object/duplicable_test.rb
index 042f5cfb34..b984becce3 100644
--- a/activesupport/test/core_ext/object/duplicable_test.rb
+++ b/activesupport/test/core_ext/object/duplicable_test.rb
@@ -1,19 +1,31 @@
-require 'abstract_unit'
-require 'bigdecimal'
-require 'active_support/core_ext/object/duplicable'
-require 'active_support/core_ext/numeric/time'
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "bigdecimal"
+require "active_support/core_ext/object/duplicable"
+require "active_support/core_ext/numeric/time"
 
 class DuplicableTest < ActiveSupport::TestCase
-  RAISE_DUP  = [nil, false, true, :symbol, 1, 2.3, method(:puts)]
-  ALLOW_DUP = ['1', Object.new, /foo/, [], {}, Time.now, Class.new, Module.new]
-  ALLOW_DUP << BigDecimal.new('4.56')
+  if RUBY_VERSION >= "2.5.0"
+    RAISE_DUP = [method(:puts)]
+    ALLOW_DUP = ["1", "symbol_from_string".to_sym, Object.new, /foo/, [], {}, Time.now, Class.new, Module.new, BigDecimal("4.56"), nil, false, true, 1, 2.3, Complex(1), Rational(1)]
+  elsif RUBY_VERSION >= "2.4.1"
+    RAISE_DUP = [method(:puts), Complex(1), Rational(1)]
+    ALLOW_DUP = ["1", "symbol_from_string".to_sym, Object.new, /foo/, [], {}, Time.now, Class.new, Module.new, BigDecimal("4.56"), nil, false, true, 1, 2.3]
+  elsif RUBY_VERSION >= "2.4.0"  # Due to 2.4.0 bug. This elsif cannot be removed unless we drop 2.4.0 support...
+    RAISE_DUP = [method(:puts), Complex(1), Rational(1), "symbol_from_string".to_sym]
+    ALLOW_DUP = ["1", Object.new, /foo/, [], {}, Time.now, Class.new, Module.new, BigDecimal("4.56"), nil, false, true, 1, 2.3]
+  else
+    RAISE_DUP = [nil, false, true, :symbol, 1, 2.3, method(:puts), Complex(1), Rational(1)]
+    ALLOW_DUP = ["1", Object.new, /foo/, [], {}, Time.now, Class.new, Module.new, BigDecimal("4.56")]
+  end
 
   def test_duplicable
     rubinius_skip "* Method#dup is allowed at the moment on Rubinius\n" \
                   "* https://github.com/rubinius/rubinius/issues/3089"
 
     RAISE_DUP.each do |v|
-      assert !v.duplicable?
+      assert !v.duplicable?, "#{ v.inspect } should not be duplicable"
       assert_raises(TypeError, v.class.name) { v.dup }
     end
 
diff --git a/activesupport/test/core_ext/object/inclusion_test.rb b/activesupport/test/core_ext/object/inclusion_test.rb
index 32d512eca3..52c21f2e8e 100644
--- a/activesupport/test/core_ext/object/inclusion_test.rb
+++ b/activesupport/test/core_ext/object/inclusion_test.rb
@@ -1,10 +1,12 @@
-require 'abstract_unit'
-require 'active_support/core_ext/object/inclusion'
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "active_support/core_ext/object/inclusion"
 
 class InTest < ActiveSupport::TestCase
   def test_in_array
-    assert 1.in?([1,2])
-    assert !3.in?([1,2])
+    assert 1.in?([1, 2])
+    assert !3.in?([1, 2])
   end
 
   def test_in_hash
@@ -25,7 +27,7 @@ class InTest < ActiveSupport::TestCase
   end
 
   def test_in_set
-    s = Set.new([1,2])
+    s = Set.new([1, 2])
     assert 1.in?(s)
     assert !3.in?(s)
   end
@@ -46,11 +48,11 @@ class InTest < ActiveSupport::TestCase
     assert !A.in?(A)
     assert !A.in?(D)
   end
-  
+
   def test_no_method_catching
     assert_raise(ArgumentError) { 1.in?(1) }
   end
-  
+
   def test_presence_in
     assert_equal "stuff", "stuff".presence_in(%w( lots of stuff ))
     assert_nil "stuff".presence_in(%w( lots of crap ))
diff --git a/activesupport/test/core_ext/object/instance_variables_test.rb b/activesupport/test/core_ext/object/instance_variables_test.rb
index 9f4c5dc4f1..a3d8daab5b 100644
--- a/activesupport/test/core_ext/object/instance_variables_test.rb
+++ b/activesupport/test/core_ext/object/instance_variables_test.rb
@@ -1,11 +1,13 @@
-require 'abstract_unit'
-require 'active_support/core_ext/object'
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "active_support/core_ext/object"
 
 class ObjectInstanceVariableTest < ActiveSupport::TestCase
   def setup
     @source, @dest = Object.new, Object.new
-    @source.instance_variable_set(:@bar, 'bar')
-    @source.instance_variable_set(:@baz, 'baz')
+    @source.instance_variable_set(:@bar, "bar")
+    @source.instance_variable_set(:@baz, "baz")
   end
 
   def test_instance_variable_names
@@ -13,19 +15,19 @@ class ObjectInstanceVariableTest < ActiveSupport::TestCase
   end
 
   def test_instance_values
-    assert_equal({'bar' => 'bar', 'baz' => 'baz'}, @source.instance_values)
+    assert_equal({ "bar" => "bar", "baz" => "baz" }, @source.instance_values)
   end
 
   def test_instance_exec_passes_arguments_to_block
-    assert_equal %w(hello goodbye), 'hello'.instance_exec('goodbye') { |v| [self, v] }
+    assert_equal %w(hello goodbye), "hello".dup.instance_exec("goodbye") { |v| [self, v] }
   end
 
   def test_instance_exec_with_frozen_obj
-    assert_equal %w(olleh goodbye), 'hello'.freeze.instance_exec('goodbye') { |v| [reverse, v] }
+    assert_equal %w(olleh goodbye), "hello".freeze.instance_exec("goodbye") { |v| [reverse, v] }
   end
 
   def test_instance_exec_nested
-    assert_equal %w(goodbye olleh bar), 'hello'.instance_exec('goodbye') { |arg|
-      [arg] + instance_exec('bar') { |v| [reverse, v] } }
+    assert_equal %w(goodbye olleh bar), "hello".dup.instance_exec("goodbye") { |arg|
+      [arg] + instance_exec("bar") { |v| [reverse, v] } }
   end
 end
diff --git a/activesupport/test/core_ext/object/json_cherry_pick_test.rb b/activesupport/test/core_ext/object/json_cherry_pick_test.rb
index 2f7ea3a497..22659a4050 100644
--- a/activesupport/test/core_ext/object/json_cherry_pick_test.rb
+++ b/activesupport/test/core_ext/object/json_cherry_pick_test.rb
@@ -1,4 +1,6 @@
-require 'abstract_unit'
+# frozen_string_literal: true
+
+require "abstract_unit"
 
 # These test cases were added to test that cherry-picking the json extensions
 # works correctly, primarily for dependencies problems reported in #16131. They
@@ -9,7 +11,7 @@ class JsonCherryPickTest < ActiveSupport::TestCase
   include ActiveSupport::Testing::Isolation
 
   def test_time_as_json
-    require_or_skip 'active_support/core_ext/object/json'
+    require_or_skip "active_support/core_ext/object/json"
 
     expected = Time.new(2004, 7, 25)
     actual   = Time.parse(expected.as_json)
@@ -18,7 +20,7 @@ class JsonCherryPickTest < ActiveSupport::TestCase
   end
 
   def test_date_as_json
-    require_or_skip 'active_support/core_ext/object/json'
+    require_or_skip "active_support/core_ext/object/json"
 
     expected = Date.new(2004, 7, 25)
     actual   = Date.parse(expected.as_json)
@@ -27,7 +29,7 @@ class JsonCherryPickTest < ActiveSupport::TestCase
   end
 
   def test_datetime_as_json
-    require_or_skip 'active_support/core_ext/object/json'
+    require_or_skip "active_support/core_ext/object/json"
 
     expected = DateTime.new(2004, 7, 25)
     actual   = DateTime.parse(expected.as_json)
diff --git a/activesupport/test/core_ext/object/json_gem_encoding_test.rb b/activesupport/test/core_ext/object/json_gem_encoding_test.rb
index 2cbb1d590f..4cdb6ed09f 100644
--- a/activesupport/test/core_ext/object/json_gem_encoding_test.rb
+++ b/activesupport/test/core_ext/object/json_gem_encoding_test.rb
@@ -1,6 +1,8 @@
-require 'abstract_unit'
-require 'json'
-require 'json/encoding_test_cases'
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "json"
+require "json/encoding_test_cases"
 
 # These test cases were added to test that we do not interfere with json gem's
 # output when the AS encoder is loaded, primarily for problems reported in
@@ -13,7 +15,7 @@ require 'json/encoding_test_cases'
 # we need to require this upfront to ensure we don't get a false failure, but
 # ideally we should just fix the BigDecimal core_ext to not change to_s without
 # arguments.
-require 'active_support/core_ext/big_decimal'
+require "active_support/core_ext/big_decimal"
 
 class JsonGemEncodingTest < ActiveSupport::TestCase
   include ActiveSupport::Testing::Isolation
@@ -48,7 +50,7 @@ class JsonGemEncodingTest < ActiveSupport::TestCase
         exception = e
       end
 
-      require_or_skip 'active_support/core_ext/object/json'
+      require_or_skip "active_support/core_ext/object/json"
 
       if exception
         assert_raises_with_message JSON::GeneratorError, e.message do
diff --git a/activesupport/test/core_ext/object/to_param_test.rb b/activesupport/test/core_ext/object/to_param_test.rb
index 30a7557dc2..612156bd99 100644
--- a/activesupport/test/core_ext/object/to_param_test.rb
+++ b/activesupport/test/core_ext/object/to_param_test.rb
@@ -1,5 +1,7 @@
-require 'abstract_unit'
-require 'active_support/core_ext/object/to_param'
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "active_support/core_ext/object/to_param"
 
 class ToParamTest < ActiveSupport::TestCase
   class CustomString < String
@@ -10,8 +12,8 @@ class ToParamTest < ActiveSupport::TestCase
 
   def test_object
     foo = Object.new
-    def foo.to_s; 'foo' end
-    assert_equal 'foo', foo.to_param
+    def foo.to_s; "foo" end
+    assert_equal "foo", foo.to_param
   end
 
   def test_nil
@@ -25,13 +27,13 @@ class ToParamTest < ActiveSupport::TestCase
 
   def test_array
     # Empty Array
-    assert_equal '', [].to_param
+    assert_equal "", [].to_param
 
     array = [1, 2, 3, 4]
     assert_equal "1/2/3/4", array.to_param
 
     # Array of different objects
-    array = [1, '3', { a: 1, b: 2 }, nil, true, false, CustomString.new('object')]
+    array = [1, "3", { a: 1, b: 2 }, nil, true, false, CustomString.new("object")]
     assert_equal "1/3/a=1&b=2//true/false/custom-object", array.to_param
   end
 end
diff --git a/activesupport/test/core_ext/object/to_query_test.rb b/activesupport/test/core_ext/object/to_query_test.rb
index 09cab3ed35..7593bcfa4d 100644
--- a/activesupport/test/core_ext/object/to_query_test.rb
+++ b/activesupport/test/core_ext/object/to_query_test.rb
@@ -1,82 +1,84 @@
-require 'abstract_unit'
-require 'active_support/ordered_hash'
-require 'active_support/core_ext/object/to_query'
-require 'active_support/core_ext/string/output_safety'
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "active_support/ordered_hash"
+require "active_support/core_ext/object/to_query"
+require "active_support/core_ext/string/output_safety"
 
 class ToQueryTest < ActiveSupport::TestCase
   def test_simple_conversion
-    assert_query_equal 'a=10', :a => 10
+    assert_query_equal "a=10", a: 10
   end
 
   def test_cgi_escaping
-    assert_query_equal 'a%3Ab=c+d', 'a:b' => 'c d'
+    assert_query_equal "a%3Ab=c+d", "a:b" => "c d"
   end
 
   def test_html_safe_parameter_key
-    assert_query_equal 'a%3Ab=c+d', 'a:b'.html_safe => 'c d'
+    assert_query_equal "a%3Ab=c+d", "a:b".html_safe => "c d"
   end
 
   def test_html_safe_parameter_value
-    assert_query_equal 'a=%5B10%5D', 'a' => '[10]'.html_safe
+    assert_query_equal "a=%5B10%5D", "a" => "[10]".html_safe
   end
 
   def test_nil_parameter_value
     empty = Object.new
     def empty.to_param; nil end
-    assert_query_equal 'a=', 'a' => empty
+    assert_query_equal "a=", "a" => empty
   end
 
   def test_nested_conversion
-    assert_query_equal 'person%5Blogin%5D=seckar&person%5Bname%5D=Nicholas',
-      :person => Hash[:login, 'seckar', :name, 'Nicholas']
+    assert_query_equal "person%5Blogin%5D=seckar&person%5Bname%5D=Nicholas",
+      person: Hash[:login, "seckar", :name, "Nicholas"]
   end
 
   def test_multiple_nested
-    assert_query_equal 'account%5Bperson%5D%5Bid%5D=20&person%5Bid%5D=10',
-      Hash[:account, {:person => {:id => 20}}, :person, {:id => 10}]
+    assert_query_equal "account%5Bperson%5D%5Bid%5D=20&person%5Bid%5D=10",
+      Hash[:account, { person: { id: 20 } }, :person, { id: 10 }]
   end
 
   def test_array_values
-    assert_query_equal 'person%5Bid%5D%5B%5D=10&person%5Bid%5D%5B%5D=20',
-      :person => {:id => [10, 20]}
+    assert_query_equal "person%5Bid%5D%5B%5D=10&person%5Bid%5D%5B%5D=20",
+      person: { id: [10, 20] }
   end
 
   def test_array_values_are_not_sorted
-    assert_query_equal 'person%5Bid%5D%5B%5D=20&person%5Bid%5D%5B%5D=10',
-      :person => {:id => [20, 10]}
+    assert_query_equal "person%5Bid%5D%5B%5D=20&person%5Bid%5D%5B%5D=10",
+      person: { id: [20, 10] }
   end
 
   def test_empty_array
-    assert_equal "person%5B%5D=", [].to_query('person')
+    assert_equal "person%5B%5D=", [].to_query("person")
   end
 
   def test_nested_empty_hash
-    assert_equal '',
+    assert_equal "",
       {}.to_query
-    assert_query_equal 'a=1&b%5Bc%5D=3',
-      { a: 1, b: { c: 3, d: {} } }
-    assert_query_equal '',
-      { a: {b: {c: {}}} }
-    assert_query_equal 'b%5Bc%5D=false&b%5Be%5D=&b%5Bf%5D=&p=12',
-      { p: 12, b: { c: false, e: nil, f: '' } }
-    assert_query_equal 'b%5Bc%5D=3&b%5Bf%5D=',
-      { b: { c: 3, k: {}, f: '' } }
-    assert_query_equal 'b=3',
-      {a: [], b: 3}
+    assert_query_equal "a=1&b%5Bc%5D=3",
+      a: 1, b: { c: 3, d: {} }
+    assert_query_equal "",
+      a: { b: { c: {} } }
+    assert_query_equal "b%5Bc%5D=false&b%5Be%5D=&b%5Bf%5D=&p=12",
+      p: 12, b: { c: false, e: nil, f: "" }
+    assert_query_equal "b%5Bc%5D=3&b%5Bf%5D=",
+      b: { c: 3, k: {}, f: "" }
+    assert_query_equal "b=3",
+      a: [], b: 3
   end
 
   def test_hash_with_namespace
-    hash = { name: 'Nakshay', nationality: 'Indian' }
-    assert_equal "user%5Bname%5D=Nakshay&user%5Bnationality%5D=Indian", hash.to_query('user')
+    hash = { name: "Nakshay", nationality: "Indian" }
+    assert_equal "user%5Bname%5D=Nakshay&user%5Bnationality%5D=Indian", hash.to_query("user")
   end
 
   def test_hash_sorted_lexicographically
-    hash = { type: 'human', name: 'Nakshay' }
+    hash = { type: "human", name: "Nakshay" }
     assert_equal "name=Nakshay&type=human", hash.to_query
   end
 
   private
     def assert_query_equal(expected, actual)
-      assert_equal expected.split('&'), actual.to_query.split('&')
+      assert_equal expected.split("&"), actual.to_query.split("&")
     end
 end
diff --git a/activesupport/test/core_ext/object/try_test.rb b/activesupport/test/core_ext/object/try_test.rb
index 25bf0207b8..fe68b24bf5 100644
--- a/activesupport/test/core_ext/object/try_test.rb
+++ b/activesupport/test/core_ext/object/try_test.rb
@@ -1,5 +1,7 @@
-require 'abstract_unit'
-require 'active_support/core_ext/object'
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "active_support/core_ext/object"
 
 class ObjectTryTest < ActiveSupport::TestCase
   def setup
@@ -15,7 +17,7 @@ class ObjectTryTest < ActiveSupport::TestCase
   def test_nonexisting_method_with_arguments
     method = :undefined_method
     assert !@string.respond_to?(method)
-    assert_nil @string.try(method, 'llo', 'y')
+    assert_nil @string.try(method, "llo", "y")
   end
 
   def test_nonexisting_method_bang
@@ -27,7 +29,7 @@ class ObjectTryTest < ActiveSupport::TestCase
   def test_nonexisting_method_with_arguments_bang
     method = :undefined_method
     assert !@string.respond_to?(method)
-    assert_raise(NoMethodError) { @string.try!(method, 'llo', 'y') }
+    assert_raise(NoMethodError) { @string.try!(method, "llo", "y") }
   end
 
   def test_valid_method
@@ -35,11 +37,11 @@ class ObjectTryTest < ActiveSupport::TestCase
   end
 
   def test_argument_forwarding
-    assert_equal 'Hey', @string.try(:sub, 'llo', 'y')
+    assert_equal "Hey", @string.try(:sub, "llo", "y")
   end
 
   def test_block_forwarding
-    assert_equal 'Hey', @string.try(:sub, 'llo') { |match| 'y' }
+    assert_equal "Hey", @string.try(:sub, "llo") { |match| "y" }
   end
 
   def test_nil_to_type
@@ -48,7 +50,7 @@ class ObjectTryTest < ActiveSupport::TestCase
   end
 
   def test_false_try
-    assert_equal 'false', false.try(:to_s)
+    assert_equal "false", false.try(:to_s)
   end
 
   def test_try_only_block
@@ -78,7 +80,7 @@ class ObjectTryTest < ActiveSupport::TestCase
       private
 
         def private_method
-          'private method'
+          "private method"
         end
     end
 
@@ -90,7 +92,7 @@ class ObjectTryTest < ActiveSupport::TestCase
       private
 
         def private_method
-          'private method'
+          "private method"
         end
     end
 
@@ -99,22 +101,22 @@ class ObjectTryTest < ActiveSupport::TestCase
 
   class Decorator < SimpleDelegator
     def delegator_method
-      'delegator method'
+      "delegator method"
     end
 
     def reverse
-      'overridden reverse'
+      "overridden reverse"
     end
 
     private
 
       def private_delegator_method
-        'private delegator method'
+        "private delegator method"
       end
   end
 
   def test_try_with_method_on_delegator
-    assert_equal 'delegator method', Decorator.new(@string).try(:delegator_method)
+    assert_equal "delegator method", Decorator.new(@string).try(:delegator_method)
   end
 
   def test_try_with_method_on_delegator_target
@@ -122,7 +124,7 @@ class ObjectTryTest < ActiveSupport::TestCase
   end
 
   def test_try_with_overridden_method_on_delegator
-    assert_equal 'overridden reverse', Decorator.new(@string).reverse
+    assert_equal "overridden reverse", Decorator.new(@string).reverse
   end
 
   def test_try_with_private_method_on_delegator
@@ -140,7 +142,7 @@ class ObjectTryTest < ActiveSupport::TestCase
       private
 
         def private_method
-          'private method'
+          "private method"
         end
     end
 
@@ -152,7 +154,7 @@ class ObjectTryTest < ActiveSupport::TestCase
       private
 
         def private_method
-          'private method'
+          "private method"
         end
     end
 
diff --git a/activesupport/test/core_ext/range_ext_test.rb b/activesupport/test/core_ext/range_ext_test.rb
index f28cebda3d..903c173e59 100644
--- a/activesupport/test/core_ext/range_ext_test.rb
+++ b/activesupport/test/core_ext/range_ext_test.rb
@@ -1,7 +1,9 @@
-require 'abstract_unit'
-require 'active_support/time'
-require 'active_support/core_ext/numeric'
-require 'active_support/core_ext/range'
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "active_support/time"
+require "active_support/core_ext/numeric"
+require "active_support/core_ext/range"
 
 class RangeTest < ActiveSupport::TestCase
   def test_to_s_from_dates
@@ -14,6 +16,11 @@ class RangeTest < ActiveSupport::TestCase
     assert_equal "BETWEEN '2005-12-10 15:30:00' AND '2005-12-10 17:30:00'", date_range.to_s(:db)
   end
 
+  def test_to_s_with_alphabets
+    alphabet_range = ("a".."z")
+    assert_equal "BETWEEN 'a' AND 'z'", alphabet_range.to_s(:db)
+  end
+
   def test_to_s_with_numeric
     number_range = (1..100)
     assert_equal "BETWEEN '1' AND '100'", number_range.to_s(:db)
@@ -66,15 +73,15 @@ class RangeTest < ActiveSupport::TestCase
   end
 
   def test_exclusive_end_should_not_include_identical_with_inclusive_end
-    assert !(1...10).include?(1..10)
+    assert_not_includes (1...10), 1..10
   end
 
   def test_should_not_include_overlapping_first
-    assert !(2..8).include?(1..3)
+    assert_not_includes (2..8), 1..3
   end
 
   def test_should_not_include_overlapping_last
-    assert !(2..8).include?(5..9)
+    assert_not_includes (2..8), 5..9
   end
 
   def test_should_include_identical_exclusive_with_floats
@@ -99,24 +106,27 @@ class RangeTest < ActiveSupport::TestCase
   end
 
   def test_each_on_time_with_zone
-    twz = ActiveSupport::TimeWithZone.new(nil, ActiveSupport::TimeZone['Eastern Time (US & Canada)'] , Time.utc(2006,11,28,10,30))
+    twz = ActiveSupport::TimeWithZone.new(nil, ActiveSupport::TimeZone["Eastern Time (US & Canada)"], Time.utc(2006, 11, 28, 10, 30))
     assert_raises TypeError do
       ((twz - 1.hour)..twz).each {}
     end
   end
 
   def test_step_on_time_with_zone
-    twz = ActiveSupport::TimeWithZone.new(nil, ActiveSupport::TimeZone['Eastern Time (US & Canada)'] , Time.utc(2006,11,28,10,30))
+    twz = ActiveSupport::TimeWithZone.new(nil, ActiveSupport::TimeZone["Eastern Time (US & Canada)"], Time.utc(2006, 11, 28, 10, 30))
     assert_raises TypeError do
       ((twz - 1.hour)..twz).step(1) {}
     end
   end
 
   def test_include_on_time_with_zone
-    twz = ActiveSupport::TimeWithZone.new(nil, ActiveSupport::TimeZone['Eastern Time (US & Canada)'] , Time.utc(2006,11,28,10,30))
-    assert_raises TypeError do
-      ((twz - 1.hour)..twz).include?(twz)
-    end
+    twz = ActiveSupport::TimeWithZone.new(nil, ActiveSupport::TimeZone["Eastern Time (US & Canada)"], Time.utc(2006, 11, 28, 10, 30))
+    assert ((twz - 1.hour)..twz).include?(twz)
+  end
+
+  def test_case_equals_on_time_with_zone
+    twz = ActiveSupport::TimeWithZone.new(nil, ActiveSupport::TimeZone["Eastern Time (US & Canada)"], Time.utc(2006, 11, 28, 10, 30))
+    assert ((twz - 1.hour)..twz) === twz
   end
 
   def test_date_time_with_each
diff --git a/activesupport/test/core_ext/regexp_ext_test.rb b/activesupport/test/core_ext/regexp_ext_test.rb
index c2398d31bd..5737bdafda 100644
--- a/activesupport/test/core_ext/regexp_ext_test.rb
+++ b/activesupport/test/core_ext/regexp_ext_test.rb
@@ -1,5 +1,7 @@
-require 'abstract_unit'
-require 'active_support/core_ext/regexp'
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "active_support/core_ext/regexp"
 
 class RegexpExtAccessTests < ActiveSupport::TestCase
   def test_multiline
@@ -7,4 +9,28 @@ class RegexpExtAccessTests < ActiveSupport::TestCase
     assert_equal false, //.multiline?
     assert_equal false, /(?m:)/.multiline?
   end
+
+  # Based on https://github.com/ruby/ruby/blob/trunk/test/ruby/test_regexp.rb.
+  def test_match_p
+    /back(...)/ =~ "backref"
+    # must match here, but not in a separate method, e.g., assert_send,
+    # to check if $~ is affected or not.
+    assert_equal false, //.match?(nil)
+    assert_equal true, //.match?("")
+    assert_equal true, /.../.match?(:abc)
+    assert_raise(TypeError) { /.../.match?(Object.new) }
+    assert_equal true, /b/.match?("abc")
+    assert_equal true, /b/.match?("abc", 1)
+    assert_equal true, /../.match?("abc", 1)
+    assert_equal true, /../.match?("abc", -2)
+    assert_equal false, /../.match?("abc", -4)
+    assert_equal false, /../.match?("abc", 4)
+    assert_equal true, /\z/.match?("")
+    assert_equal true, /\z/.match?("abc")
+    assert_equal true, /R.../.match?("Ruby")
+    assert_equal false, /R.../.match?("Ruby", 1)
+    assert_equal false, /P.../.match?("Ruby")
+    assert_equal "backref", $&
+    assert_equal "ref", $1
+  end
 end
diff --git a/activesupport/test/core_ext/secure_random_test.rb b/activesupport/test/core_ext/secure_random_test.rb
index dfacb7fe9f..7067fb524c 100644
--- a/activesupport/test/core_ext/secure_random_test.rb
+++ b/activesupport/test/core_ext/secure_random_test.rb
@@ -1,5 +1,7 @@
-require 'abstract_unit'
-require 'active_support/core_ext/securerandom'
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "active_support/core_ext/securerandom"
 
 class SecureRandomTest < ActiveSupport::TestCase
   def test_base58
diff --git a/activesupport/test/core_ext/string_ext_test.rb b/activesupport/test/core_ext/string_ext_test.rb
index d68a77680b..5c5abe9fd1 100644
--- a/activesupport/test/core_ext/string_ext_test.rb
+++ b/activesupport/test/core_ext/string_ext_test.rb
@@ -1,16 +1,19 @@
-require 'date'
-require 'abstract_unit'
-require 'inflector_test_cases'
-require 'constantize_test_cases'
-
-require 'active_support/inflector'
-require 'active_support/core_ext/string'
-require 'active_support/time'
-require 'active_support/core_ext/string/strip'
-require 'active_support/core_ext/string/output_safety'
-require 'active_support/core_ext/string/indent'
-require 'time_zone_test_helpers'
-require 'yaml'
+# frozen_string_literal: true
+
+require "date"
+require "abstract_unit"
+require "timeout"
+require "inflector_test_cases"
+require "constantize_test_cases"
+
+require "active_support/inflector"
+require "active_support/core_ext/string"
+require "active_support/time"
+require "active_support/core_ext/string/strip"
+require "active_support/core_ext/string/output_safety"
+require "active_support/core_ext/string/indent"
+require "time_zone_test_helpers"
+require "yaml"
 
 class StringInflectionsTest < ActiveSupport::TestCase
   include InflectorTestCases
@@ -18,12 +21,12 @@ class StringInflectionsTest < ActiveSupport::TestCase
   include TimeZoneTestHelpers
 
   def test_strip_heredoc_on_an_empty_string
-    assert_equal '', ''.strip_heredoc
+    assert_equal "", "".strip_heredoc
   end
 
   def test_strip_heredoc_on_a_string_with_no_lines
-    assert_equal 'x', 'x'.strip_heredoc
-    assert_equal 'x', '    x'.strip_heredoc
+    assert_equal "x", "x".strip_heredoc
+    assert_equal "x", "    x".strip_heredoc
   end
 
   def test_strip_heredoc_on_a_heredoc_with_no_margin
@@ -60,7 +63,7 @@ class StringInflectionsTest < ActiveSupport::TestCase
     assert_equal("blargles", "blargle".pluralize(2))
   end
 
-  test 'pluralize with count = 1 still returns new string' do
+  test "pluralize with count = 1 still returns new string" do
     name = "Kuldeep"
     assert_not_same name.pluralize(1), name
   end
@@ -77,6 +80,12 @@ class StringInflectionsTest < ActiveSupport::TestCase
     end
   end
 
+  def test_titleize_with_keep_id_suffix
+    MixtureToTitleCaseWithKeepIdSuffix.each do |before, titleized|
+      assert_equal(titleized, before.titleize(keep_id_suffix: true))
+    end
+  end
+
   def test_upcase_first
     assert_equal "What a Lovely Day", "what a Lovely Day".upcase_first
   end
@@ -96,7 +105,14 @@ class StringInflectionsTest < ActiveSupport::TestCase
   end
 
   def test_camelize_lower
-    assert_equal('capital', 'Capital'.camelize(:lower))
+    assert_equal("capital", "Capital".camelize(:lower))
+  end
+
+  def test_camelize_invalid_option
+    e = assert_raise ArgumentError do
+      "Capital".camelize(nil)
+    end
+    assert_equal("Invalid option, use either :upper or :lower.", e.message)
   end
 
   def test_dasherize
@@ -152,53 +168,37 @@ class StringInflectionsTest < ActiveSupport::TestCase
 
   def test_string_parameterized_normal
     StringToParameterized.each do |normal, slugged|
-      assert_equal(normal.parameterize, slugged)
+      assert_equal(slugged, normal.parameterize)
     end
   end
 
   def test_string_parameterized_normal_preserve_case
     StringToParameterizedPreserveCase.each do |normal, slugged|
-      assert_equal(normal.parameterize(preserve_case: true), slugged)
+      assert_equal(slugged, normal.parameterize(preserve_case: true))
     end
   end
 
   def test_string_parameterized_no_separator
     StringToParameterizeWithNoSeparator.each do |normal, slugged|
-      assert_equal(normal.parameterize(separator: ''), slugged)
-    end
-  end
-
-  def test_string_parameterized_no_separator_deprecated
-    StringToParameterizeWithNoSeparator.each do |normal, slugged|
-      assert_deprecated(/Passing the separator argument as a positional parameter is deprecated and will soon be removed. Use `separator: ''` instead./i) do
-        assert_equal(normal.parameterize(''), slugged)
-      end
+      assert_equal(slugged, normal.parameterize(separator: ""))
     end
   end
 
   def test_string_parameterized_no_separator_preserve_case
     StringToParameterizePreserveCaseWithNoSeparator.each do |normal, slugged|
-      assert_equal(normal.parameterize(separator: '', preserve_case: true), slugged)
+      assert_equal(slugged, normal.parameterize(separator: "", preserve_case: true))
     end
   end
 
   def test_string_parameterized_underscore
     StringToParameterizeWithUnderscore.each do |normal, slugged|
-      assert_equal(normal.parameterize(separator: '_'), slugged)
-    end
-  end
-
-  def test_string_parameterized_underscore_deprecated
-    StringToParameterizeWithUnderscore.each do |normal, slugged|
-      assert_deprecated(/Passing the separator argument as a positional parameter is deprecated and will soon be removed. Use `separator: '_'` instead./i) do
-        assert_equal(normal.parameterize('_'), slugged)
-      end
+      assert_equal(slugged, normal.parameterize(separator: "_"))
     end
   end
 
   def test_string_parameterized_underscore_preserve_case
-    StringToParameterizePreserceCaseWithUnderscore.each do |normal, slugged|
-      assert_equal(normal.parameterize(separator: '_', preserve_case: true), slugged)
+    StringToParameterizePreserveCaseWithUnderscore.each do |normal, slugged|
+      assert_equal(slugged, normal.parameterize(separator: "_", preserve_case: true))
     end
   end
 
@@ -214,31 +214,37 @@ class StringInflectionsTest < ActiveSupport::TestCase
     end
   end
 
+  def test_humanize_with_keep_id_suffix
+    UnderscoreToHumanWithKeepIdSuffix.each do |underscore, human|
+      assert_equal(human, underscore.humanize(keep_id_suffix: true))
+    end
+  end
+
   def test_humanize_with_html_escape
-    assert_equal 'Hello', ERB::Util.html_escape("hello").humanize
+    assert_equal "Hello", ERB::Util.html_escape("hello").humanize
   end
 
   def test_ord
-    assert_equal 97, 'a'.ord
-    assert_equal 97, 'abc'.ord
+    assert_equal 97, "a".ord
+    assert_equal 97, "abc".ord
   end
 
   def test_starts_ends_with_alias
     s = "hello"
-    assert s.starts_with?('h')
-    assert s.starts_with?('hel')
-    assert !s.starts_with?('el')
+    assert s.starts_with?("h")
+    assert s.starts_with?("hel")
+    assert !s.starts_with?("el")
 
-    assert s.ends_with?('o')
-    assert s.ends_with?('lo')
-    assert !s.ends_with?('el')
+    assert s.ends_with?("o")
+    assert s.ends_with?("lo")
+    assert !s.ends_with?("el")
   end
 
   def test_string_squish
     original = %{\u205f\u3000 A string surrounded by various unicode spaces,
-      with tabs(\t\t), newlines(\n\n), unicode nextlines(\u0085\u0085) and many spaces(  ). \u00a0\u2007}
+      with tabs(\t\t), newlines(\n\n), unicode nextlines(\u0085\u0085) and many spaces(  ). \u00a0\u2007}.dup
 
-    expected = "A string surrounded by various unicode spaces, " +
+    expected = "A string surrounded by various unicode spaces, " \
       "with tabs( ), newlines( ), unicode nextlines( ) and many spaces( )."
 
     # Make sure squish returns what we expect:
@@ -263,16 +269,16 @@ class StringInflectionsTest < ActiveSupport::TestCase
   end
 
   def test_truncate_with_omission_and_separator
-    assert_equal "Hello[...]", "Hello World!".truncate(10, :omission => "[...]")
-    assert_equal "Hello[...]", "Hello Big World!".truncate(13, :omission => "[...]", :separator => ' ')
-    assert_equal "Hello Big[...]", "Hello Big World!".truncate(14, :omission => "[...]", :separator => ' ')
-    assert_equal "Hello Big[...]", "Hello Big World!".truncate(15, :omission => "[...]", :separator => ' ')
+    assert_equal "Hello[...]", "Hello World!".truncate(10, omission: "[...]")
+    assert_equal "Hello[...]", "Hello Big World!".truncate(13, omission: "[...]", separator: " ")
+    assert_equal "Hello Big[...]", "Hello Big World!".truncate(14, omission: "[...]", separator: " ")
+    assert_equal "Hello Big[...]", "Hello Big World!".truncate(15, omission: "[...]", separator: " ")
   end
 
   def test_truncate_with_omission_and_regexp_separator
-    assert_equal "Hello[...]", "Hello Big World!".truncate(13, :omission => "[...]", :separator => /\s/)
-    assert_equal "Hello Big[...]", "Hello Big World!".truncate(14, :omission => "[...]", :separator => /\s/)
-    assert_equal "Hello Big[...]", "Hello Big World!".truncate(15, :omission => "[...]", :separator => /\s/)
+    assert_equal "Hello[...]", "Hello Big World!".truncate(13, omission: "[...]", separator: /\s/)
+    assert_equal "Hello Big[...]", "Hello Big World!".truncate(14, omission: "[...]", separator: /\s/)
+    assert_equal "Hello Big[...]", "Hello Big World!".truncate(15, omission: "[...]", separator: /\s/)
   end
 
   def test_truncate_words
@@ -281,33 +287,33 @@ class StringInflectionsTest < ActiveSupport::TestCase
   end
 
   def test_truncate_words_with_omission
-    assert_equal "Hello Big World!", "Hello Big World!".truncate_words(3, :omission => "[...]")
-    assert_equal "Hello Big[...]", "Hello Big World!".truncate_words(2, :omission => "[...]")
+    assert_equal "Hello Big World!", "Hello Big World!".truncate_words(3, omission: "[...]")
+    assert_equal "Hello Big[...]", "Hello Big World!".truncate_words(2, omission: "[...]")
   end
 
   def test_truncate_words_with_separator
-    assert_equal "Hello<br>Big<br>World!...", "Hello<br>Big<br>World!<br>".truncate_words(3, :separator => '<br>')
-    assert_equal "Hello<br>Big<br>World!", "Hello<br>Big<br>World!".truncate_words(3, :separator => '<br>')
-    assert_equal "Hello\n<br>Big...", "Hello\n<br>Big<br>Wide<br>World!".truncate_words(2, :separator => '<br>')
+    assert_equal "Hello<br>Big<br>World!...", "Hello<br>Big<br>World!<br>".truncate_words(3, separator: "<br>")
+    assert_equal "Hello<br>Big<br>World!", "Hello<br>Big<br>World!".truncate_words(3, separator: "<br>")
+    assert_equal "Hello\n<br>Big...", "Hello\n<br>Big<br>Wide<br>World!".truncate_words(2, separator: "<br>")
   end
 
   def test_truncate_words_with_separator_and_omission
-    assert_equal "Hello<br>Big<br>World![...]", "Hello<br>Big<br>World!<br>".truncate_words(3, :omission => "[...]", :separator => '<br>')
-    assert_equal "Hello<br>Big<br>World!", "Hello<br>Big<br>World!".truncate_words(3, :omission => "[...]", :separator => '<br>')
+    assert_equal "Hello<br>Big<br>World![...]", "Hello<br>Big<br>World!<br>".truncate_words(3, omission: "[...]", separator: "<br>")
+    assert_equal "Hello<br>Big<br>World!", "Hello<br>Big<br>World!".truncate_words(3, omission: "[...]", separator: "<br>")
   end
 
   def test_truncate_words_with_complex_string
     Timeout.timeout(10) do
       complex_string = "aa aa aaa aa aaa aaa aaa aa aaa aaa aaa aaa aaa aaa aaa aaa aaa aaa aaaa aaaaa aaaaa aaaaaa aa aa aa aaa aa  aaa aa aa aa aa a aaa aaa \n a aaa <<s"
-      assert_equal complex_string.truncate_words(80), complex_string
+      assert_equal complex_string, complex_string.truncate_words(80)
     end
   rescue Timeout::Error
     assert false
   end
 
   def test_truncate_multibyte
-    assert_equal "\354\225\204\353\246\254\353\236\221 \354\225\204\353\246\254 ...".force_encoding(Encoding::UTF_8),
-      "\354\225\204\353\246\254\353\236\221 \354\225\204\353\246\254 \354\225\204\353\235\274\353\246\254\354\230\244".force_encoding(Encoding::UTF_8).truncate(10)
+    assert_equal "\354\225\204\353\246\254\353\236\221 \354\225\204\353\246\254 ...".dup.force_encoding(Encoding::UTF_8),
+      "\354\225\204\353\246\254\353\236\221 \354\225\204\353\246\254 \354\225\204\353\235\274\353\246\254\354\230\244".dup.force_encoding(Encoding::UTF_8).truncate(10)
   end
 
   def test_truncate_should_not_be_html_safe
@@ -328,7 +334,7 @@ class StringInflectionsTest < ActiveSupport::TestCase
   end
 
   def test_remove!
-    original = "This is a very good day to die"
+    original = "This is a very good day to die".dup
     assert_equal "This is a good day to die", original.remove!(" very")
     assert_equal "This is a good day to die", original
     assert_equal "This is a good day", original.remove!(" to ", /die/)
@@ -355,7 +361,7 @@ class StringAccessTest < ActiveSupport::TestCase
 
   test "#at with Regex, returns the matching portion of the string" do
     assert_equal "lo", "hello".at(/lo/)
-    assert_equal nil, "hello".at(/nonexisting/)
+    assert_nil "hello".at(/nonexisting/)
   end
 
   test "#from with positive Integer, returns substring from the given position to the end" do
@@ -381,14 +387,14 @@ class StringAccessTest < ActiveSupport::TestCase
 
   test "#first returns the first character" do
     assert_equal "h", "hello".first
-    assert_equal 'x', 'x'.first
+    assert_equal "x", "x".first
   end
 
   test "#first with Integer, returns a substring from the beginning to position" do
     assert_equal "he", "hello".first(2)
     assert_equal "", "hello".first(0)
     assert_equal "hello", "hello".first(10)
-    assert_equal 'x', 'x'.first(4)
+    assert_equal "x", "x".first(4)
   end
 
   test "#first with Integer >= string length still returns a new string" do
@@ -399,14 +405,14 @@ class StringAccessTest < ActiveSupport::TestCase
 
   test "#last returns the last character" do
     assert_equal "o", "hello".last
-    assert_equal 'x', 'x'.last
+    assert_equal "x", "x".last
   end
 
   test "#last with Integer, returns a substring from the end to position" do
     assert_equal "llo", "hello".last(3)
     assert_equal "hello", "hello".last(10)
     assert_equal "", "hello".last(0)
-    assert_equal 'x', 'x'.last(4)
+    assert_equal "x", "x".last(4)
   end
 
   test "#last with Integer >= string length still returns a new string" do
@@ -633,14 +639,14 @@ end
 
 class StringBehaviourTest < ActiveSupport::TestCase
   def test_acts_like_string
-    assert 'Bambi'.acts_like_string?
+    assert "Bambi".acts_like_string?
   end
 end
 
 class CoreExtStringMultibyteTest < ActiveSupport::TestCase
-  UTF8_STRING = 'こにちわ'
-  ASCII_STRING = 'ohayo'.encode('US-ASCII')
-  EUC_JP_STRING = 'さよなら'.encode('EUC-JP')
+  UTF8_STRING = "こにちわ"
+  ASCII_STRING = "ohayo".encode("US-ASCII")
+  EUC_JP_STRING = "さよなら".encode("EUC-JP")
   INVALID_UTF8_STRING = "\270\236\010\210\245"
 
   def test_core_ext_adds_mb_chars
@@ -661,7 +667,7 @@ end
 
 class OutputSafetyTest < ActiveSupport::TestCase
   def setup
-    @string = "hello"
+    @string = "hello".dup
     @object = Class.new(Object) do
       def to_s
         "other"
@@ -726,18 +732,18 @@ class OutputSafetyTest < ActiveSupport::TestCase
   test "Prepending safe onto unsafe yields unsafe" do
     @string.prepend "other".html_safe
     assert !@string.html_safe?
-    assert_equal @string, "otherhello"
+    assert_equal "otherhello", @string
   end
 
   test "Prepending unsafe onto safe yields escaped safe" do
     other = "other".html_safe
     other.prepend "<foo>"
     assert other.html_safe?
-    assert_equal other, "&lt;foo&gt;other"
+    assert_equal "&lt;foo&gt;other", other
   end
 
   test "Concatting safe onto unsafe yields unsafe" do
-    @other_string = "other"
+    @other_string = "other".dup
 
     string = @string.html_safe
     @other_string.concat(string)
@@ -760,7 +766,7 @@ class OutputSafetyTest < ActiveSupport::TestCase
   end
 
   test "Concatting safe onto unsafe with << yields unsafe" do
-    @other_string = "other"
+    @other_string = "other".dup
     string = @string.html_safe
 
     @other_string << string
@@ -816,12 +822,12 @@ class OutputSafetyTest < ActiveSupport::TestCase
   test "Concatting an integer to safe always yields safe" do
     string = @string.html_safe
     string = string.concat(13)
-    assert_equal "hello".concat(13), string
+    assert_equal "hello".dup.concat(13), string
     assert string.html_safe?
   end
 
-  test 'emits normal string yaml' do
-    assert_equal 'foo'.to_yaml, 'foo'.html_safe.to_yaml(:foo => 1)
+  test "emits normal string yaml" do
+    assert_equal "foo".to_yaml, "foo".html_safe.to_yaml(foo: 1)
   end
 
   test "call to_param returns a normal string" do
@@ -832,7 +838,7 @@ class OutputSafetyTest < ActiveSupport::TestCase
 
   test "ERB::Util.html_escape should escape unsafe characters" do
     string = '<>&"\''
-    expected = '&lt;&gt;&amp;&quot;&#39;'
+    expected = "&lt;&gt;&amp;&quot;&#39;"
     assert_equal expected, ERB::Util.html_escape(string)
   end
 
@@ -848,7 +854,7 @@ class OutputSafetyTest < ActiveSupport::TestCase
   end
 
   test "ERB::Util.html_escape_once only escapes once" do
-    string = '1 < 2 &amp; 3'
+    string = "1 < 2 &amp; 3"
     escaped_string = "1 &lt; 2 &amp; 3"
 
     assert_equal escaped_string, ERB::Util.html_escape_once(string)
@@ -863,15 +869,16 @@ class OutputSafetyTest < ActiveSupport::TestCase
 end
 
 class StringExcludeTest < ActiveSupport::TestCase
-  test 'inverse of #include' do
-    assert_equal false, 'foo'.exclude?('o')
-    assert_equal true, 'foo'.exclude?('p')
+  test "inverse of #include" do
+    assert_equal false, "foo".exclude?("o")
+    assert_equal true, "foo".exclude?("p")
   end
 end
 
 class StringIndentTest < ActiveSupport::TestCase
-  test 'does not indent strings that only contain newlines (edge cases)' do
-    ['', "\n", "\n" * 7].each do |str|
+  test "does not indent strings that only contain newlines (edge cases)" do
+    ["", "\n", "\n" * 7].each do |string|
+      str = string.dup
       assert_nil str.indent!(8)
       assert_equal str, str.indent(8)
       assert_equal str, str.indent(1, "\t")
@@ -893,8 +900,8 @@ class StringIndentTest < ActiveSupport::TestCase
   # Nothing is said about existing indentation that mixes spaces and tabs, so
   # there is nothing to test.
 
-  test 'uses the indent char if passed' do
-    assert_equal <<EXPECTED, <<ACTUAL.indent(4, '.')
+  test "uses the indent char if passed" do
+    assert_equal <<EXPECTED, <<ACTUAL.indent(4, ".")
 ....  def some_method(x, y)
 ....    some_code
 ....  end
@@ -904,7 +911,7 @@ EXPECTED
   end
 ACTUAL
 
-    assert_equal <<EXPECTED, <<ACTUAL.indent(2, '&nbsp;')
+    assert_equal <<EXPECTED, <<ACTUAL.indent(2, "&nbsp;")
 &nbsp;&nbsp;&nbsp;&nbsp;def some_method(x, y)
 &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;some_code
 &nbsp;&nbsp;&nbsp;&nbsp;end
@@ -919,7 +926,7 @@ ACTUAL
     assert_equal " foo\n\n bar", "foo\n\nbar".indent(1)
   end
 
-  test 'indents blank lines if told so' do
+  test "indents blank lines if told so" do
     assert_equal " foo\n \n bar", "foo\n\nbar".indent(1, nil, true)
   end
 end
diff --git a/activesupport/test/core_ext/time_ext_test.rb b/activesupport/test/core_ext/time_ext_test.rb
index 1205797fac..01cf1938be 100644
--- a/activesupport/test/core_ext/time_ext_test.rb
+++ b/activesupport/test/core_ext/time_ext_test.rb
@@ -1,541 +1,546 @@
-require 'abstract_unit'
-require 'active_support/time'
-require 'core_ext/date_and_time_behavior'
-require 'time_zone_test_helpers'
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "active_support/time"
+require "core_ext/date_and_time_behavior"
+require "time_zone_test_helpers"
 
 class TimeExtCalculationsTest < ActiveSupport::TestCase
-  def date_time_init(year,month,day,hour,minute,second,usec=0)
-    Time.local(year,month,day,hour,minute,second,usec)
+  def date_time_init(year, month, day, hour, minute, second, usec = 0)
+    Time.local(year, month, day, hour, minute, second, usec)
   end
 
   include DateAndTimeBehavior
   include TimeZoneTestHelpers
 
   def test_seconds_since_midnight
-    assert_equal 1,Time.local(2005,1,1,0,0,1).seconds_since_midnight
-    assert_equal 60,Time.local(2005,1,1,0,1,0).seconds_since_midnight
-    assert_equal 3660,Time.local(2005,1,1,1,1,0).seconds_since_midnight
-    assert_equal 86399,Time.local(2005,1,1,23,59,59).seconds_since_midnight
-    assert_equal 60.00001,Time.local(2005,1,1,0,1,0,10).seconds_since_midnight
+    assert_equal 1, Time.local(2005, 1, 1, 0, 0, 1).seconds_since_midnight
+    assert_equal 60, Time.local(2005, 1, 1, 0, 1, 0).seconds_since_midnight
+    assert_equal 3660, Time.local(2005, 1, 1, 1, 1, 0).seconds_since_midnight
+    assert_equal 86399, Time.local(2005, 1, 1, 23, 59, 59).seconds_since_midnight
+    assert_equal 60.00001, Time.local(2005, 1, 1, 0, 1, 0, 10).seconds_since_midnight
   end
 
   def test_seconds_since_midnight_at_daylight_savings_time_start
-    with_env_tz 'US/Eastern' do
+    with_env_tz "US/Eastern" do
       # dt: US: 2005 April 3rd 2:00am ST => April 3rd 3:00am DT
-      assert_equal 2*3600-1, Time.local(2005,4,3,1,59,59).seconds_since_midnight, 'just before DST start'
-      assert_equal 2*3600+1, Time.local(2005,4,3,3, 0, 1).seconds_since_midnight, 'just after DST start'
+      assert_equal 2 * 3600 - 1, Time.local(2005, 4, 3, 1, 59, 59).seconds_since_midnight, "just before DST start"
+      assert_equal 2 * 3600 + 1, Time.local(2005, 4, 3, 3, 0, 1).seconds_since_midnight, "just after DST start"
     end
 
-    with_env_tz 'NZ' do
+    with_env_tz "NZ" do
       # dt: New Zealand: 2006 October 1st 2:00am ST => October 1st 3:00am DT
-      assert_equal 2*3600-1, Time.local(2006,10,1,1,59,59).seconds_since_midnight, 'just before DST start'
-      assert_equal 2*3600+1, Time.local(2006,10,1,3, 0, 1).seconds_since_midnight, 'just after DST start'
+      assert_equal 2 * 3600 - 1, Time.local(2006, 10, 1, 1, 59, 59).seconds_since_midnight, "just before DST start"
+      assert_equal 2 * 3600 + 1, Time.local(2006, 10, 1, 3, 0, 1).seconds_since_midnight, "just after DST start"
     end
   end
 
   def test_seconds_since_midnight_at_daylight_savings_time_end
-    with_env_tz 'US/Eastern' do
+    with_env_tz "US/Eastern" do
       # st: US: 2005 October 30th 2:00am DT => October 30th 1:00am ST
       # avoid setting a time between 1:00 and 2:00 since that requires specifying whether DST is active
-      assert_equal 1*3600-1, Time.local(2005,10,30,0,59,59).seconds_since_midnight, 'just before DST end'
-      assert_equal 3*3600+1, Time.local(2005,10,30,2, 0, 1).seconds_since_midnight, 'just after DST end'
+      assert_equal 1 * 3600 - 1, Time.local(2005, 10, 30, 0, 59, 59).seconds_since_midnight, "just before DST end"
+      assert_equal 3 * 3600 + 1, Time.local(2005, 10, 30, 2, 0, 1).seconds_since_midnight, "just after DST end"
 
       # now set a time between 1:00 and 2:00 by specifying whether DST is active
       # uses: Time.local( sec, min, hour, day, month, year, wday, yday, isdst, tz )
-      assert_equal 1*3600+30*60, Time.local(0,30,1,30,10,2005,0,0,true,ENV['TZ']).seconds_since_midnight, 'before DST end'
-      assert_equal 2*3600+30*60, Time.local(0,30,1,30,10,2005,0,0,false,ENV['TZ']).seconds_since_midnight, 'after DST end'
+      assert_equal 1 * 3600 + 30 * 60, Time.local(0, 30, 1, 30, 10, 2005, 0, 0, true, ENV["TZ"]).seconds_since_midnight, "before DST end"
+      assert_equal 2 * 3600 + 30 * 60, Time.local(0, 30, 1, 30, 10, 2005, 0, 0, false, ENV["TZ"]).seconds_since_midnight, "after DST end"
     end
 
-    with_env_tz 'NZ' do
+    with_env_tz "NZ" do
       # st: New Zealand: 2006 March 19th 3:00am DT => March 19th 2:00am ST
       # avoid setting a time between 2:00 and 3:00 since that requires specifying whether DST is active
-      assert_equal 2*3600-1, Time.local(2006,3,19,1,59,59).seconds_since_midnight, 'just before DST end'
-      assert_equal 4*3600+1, Time.local(2006,3,19,3, 0, 1).seconds_since_midnight, 'just after DST end'
+      assert_equal 2 * 3600 - 1, Time.local(2006, 3, 19, 1, 59, 59).seconds_since_midnight, "just before DST end"
+      assert_equal 4 * 3600 + 1, Time.local(2006, 3, 19, 3, 0, 1).seconds_since_midnight, "just after DST end"
 
       # now set a time between 2:00 and 3:00 by specifying whether DST is active
       # uses: Time.local( sec, min, hour, day, month, year, wday, yday, isdst, tz )
-      assert_equal 2*3600+30*60, Time.local(0,30,2,19,3,2006,0,0,true, ENV['TZ']).seconds_since_midnight, 'before DST end'
-      assert_equal 3*3600+30*60, Time.local(0,30,2,19,3,2006,0,0,false,ENV['TZ']).seconds_since_midnight, 'after DST end'
+      assert_equal 2 * 3600 + 30 * 60, Time.local(0, 30, 2, 19, 3, 2006, 0, 0, true, ENV["TZ"]).seconds_since_midnight, "before DST end"
+      assert_equal 3 * 3600 + 30 * 60, Time.local(0, 30, 2, 19, 3, 2006, 0, 0, false, ENV["TZ"]).seconds_since_midnight, "after DST end"
     end
   end
 
   def test_seconds_until_end_of_day
-    assert_equal 0, Time.local(2005,1,1,23,59,59).seconds_until_end_of_day
-    assert_equal 1, Time.local(2005,1,1,23,59,58).seconds_until_end_of_day
-    assert_equal 60, Time.local(2005,1,1,23,58,59).seconds_until_end_of_day
-    assert_equal 3660, Time.local(2005,1,1,22,58,59).seconds_until_end_of_day
-    assert_equal 86399, Time.local(2005,1,1,0,0,0).seconds_until_end_of_day
+    assert_equal 0, Time.local(2005, 1, 1, 23, 59, 59).seconds_until_end_of_day
+    assert_equal 1, Time.local(2005, 1, 1, 23, 59, 58).seconds_until_end_of_day
+    assert_equal 60, Time.local(2005, 1, 1, 23, 58, 59).seconds_until_end_of_day
+    assert_equal 3660, Time.local(2005, 1, 1, 22, 58, 59).seconds_until_end_of_day
+    assert_equal 86399, Time.local(2005, 1, 1, 0, 0, 0).seconds_until_end_of_day
   end
 
   def test_seconds_until_end_of_day_at_daylight_savings_time_start
-    with_env_tz 'US/Eastern' do
+    with_env_tz "US/Eastern" do
       # dt: US: 2005 April 3rd 2:00am ST => April 3rd 3:00am DT
-      assert_equal 21*3600, Time.local(2005,4,3,1,59,59).seconds_until_end_of_day, 'just before DST start'
-      assert_equal 21*3600-2, Time.local(2005,4,3,3,0,1).seconds_until_end_of_day, 'just after DST start'
+      assert_equal 21 * 3600, Time.local(2005, 4, 3, 1, 59, 59).seconds_until_end_of_day, "just before DST start"
+      assert_equal 21 * 3600 - 2, Time.local(2005, 4, 3, 3, 0, 1).seconds_until_end_of_day, "just after DST start"
     end
 
-    with_env_tz 'NZ' do
+    with_env_tz "NZ" do
       # dt: New Zealand: 2006 October 1st 2:00am ST => October 1st 3:00am DT
-      assert_equal 21*3600, Time.local(2006,10,1,1,59,59).seconds_until_end_of_day, 'just before DST start'
-      assert_equal 21*3600-2, Time.local(2006,10,1,3,0,1).seconds_until_end_of_day, 'just after DST start'
+      assert_equal 21 * 3600, Time.local(2006, 10, 1, 1, 59, 59).seconds_until_end_of_day, "just before DST start"
+      assert_equal 21 * 3600 - 2, Time.local(2006, 10, 1, 3, 0, 1).seconds_until_end_of_day, "just after DST start"
     end
   end
 
   def test_seconds_until_end_of_day_at_daylight_savings_time_end
-    with_env_tz 'US/Eastern' do
+    with_env_tz "US/Eastern" do
       # st: US: 2005 October 30th 2:00am DT => October 30th 1:00am ST
       # avoid setting a time between 1:00 and 2:00 since that requires specifying whether DST is active
-      assert_equal 24*3600, Time.local(2005,10,30,0,59,59).seconds_until_end_of_day, 'just before DST end'
-      assert_equal 22*3600-2, Time.local(2005,10,30,2,0,1).seconds_until_end_of_day, 'just after DST end'
+      assert_equal 24 * 3600, Time.local(2005, 10, 30, 0, 59, 59).seconds_until_end_of_day, "just before DST end"
+      assert_equal 22 * 3600 - 2, Time.local(2005, 10, 30, 2, 0, 1).seconds_until_end_of_day, "just after DST end"
 
       # now set a time between 1:00 and 2:00 by specifying whether DST is active
       # uses: Time.local( sec, min, hour, day, month, year, wday, yday, isdst, tz )
-      assert_equal 24*3600-30*60-1, Time.local(0,30,1,30,10,2005,0,0,true,ENV['TZ']).seconds_until_end_of_day, 'before DST end'
-      assert_equal 23*3600-30*60-1, Time.local(0,30,1,30,10,2005,0,0,false,ENV['TZ']).seconds_until_end_of_day, 'after DST end'
+      assert_equal 24 * 3600 - 30 * 60 - 1, Time.local(0, 30, 1, 30, 10, 2005, 0, 0, true, ENV["TZ"]).seconds_until_end_of_day, "before DST end"
+      assert_equal 23 * 3600 - 30 * 60 - 1, Time.local(0, 30, 1, 30, 10, 2005, 0, 0, false, ENV["TZ"]).seconds_until_end_of_day, "after DST end"
     end
 
-    with_env_tz 'NZ' do
+    with_env_tz "NZ" do
       # st: New Zealand: 2006 March 19th 3:00am DT => March 19th 2:00am ST
       # avoid setting a time between 2:00 and 3:00 since that requires specifying whether DST is active
-      assert_equal 23*3600, Time.local(2006,3,19,1,59,59).seconds_until_end_of_day, 'just before DST end'
-      assert_equal 21*3600-2, Time.local(2006,3,19,3,0,1).seconds_until_end_of_day, 'just after DST end'
+      assert_equal 23 * 3600, Time.local(2006, 3, 19, 1, 59, 59).seconds_until_end_of_day, "just before DST end"
+      assert_equal 21 * 3600 - 2, Time.local(2006, 3, 19, 3, 0, 1).seconds_until_end_of_day, "just after DST end"
 
       # now set a time between 2:00 and 3:00 by specifying whether DST is active
       # uses: Time.local( sec, min, hour, day, month, year, wday, yday, isdst, tz )
-      assert_equal 23*3600-30*60-1, Time.local(0,30,2,19,3,2006,0,0,true, ENV['TZ']).seconds_until_end_of_day, 'before DST end'
-      assert_equal 22*3600-30*60-1, Time.local(0,30,2,19,3,2006,0,0,false,ENV['TZ']).seconds_until_end_of_day, 'after DST end'
+      assert_equal 23 * 3600 - 30 * 60 - 1, Time.local(0, 30, 2, 19, 3, 2006, 0, 0, true, ENV["TZ"]).seconds_until_end_of_day, "before DST end"
+      assert_equal 22 * 3600 - 30 * 60 - 1, Time.local(0, 30, 2, 19, 3, 2006, 0, 0, false, ENV["TZ"]).seconds_until_end_of_day, "after DST end"
     end
   end
 
   def test_sec_fraction
-    time = Time.utc(2016, 4, 23, 0, 0, Rational(1,10000000000))
-    assert_equal Rational(1,10000000000), time.sec_fraction
+    time = Time.utc(2016, 4, 23, 0, 0, Rational(1, 10000000000))
+    assert_equal Rational(1, 10000000000), time.sec_fraction
 
     time = Time.utc(2016, 4, 23, 0, 0, 0.0000000001)
     assert_equal 0.0000000001.to_r, time.sec_fraction
 
-    time = Time.utc(2016, 4, 23, 0, 0, 0, Rational(1,10000))
-    assert_equal Rational(1,10000000000), time.sec_fraction
+    time = Time.utc(2016, 4, 23, 0, 0, 0, Rational(1, 10000))
+    assert_equal Rational(1, 10000000000), time.sec_fraction
 
     time = Time.utc(2016, 4, 23, 0, 0, 0, 0.0001)
     assert_equal 0.0001.to_r / 1000000, time.sec_fraction
   end
 
   def test_beginning_of_day
-    assert_equal Time.local(2005,2,4,0,0,0), Time.local(2005,2,4,10,10,10).beginning_of_day
-    with_env_tz 'US/Eastern' do
-      assert_equal Time.local(2006,4,2,0,0,0), Time.local(2006,4,2,10,10,10).beginning_of_day, 'start DST'
-      assert_equal Time.local(2006,10,29,0,0,0), Time.local(2006,10,29,10,10,10).beginning_of_day, 'ends DST'
+    assert_equal Time.local(2005, 2, 4, 0, 0, 0), Time.local(2005, 2, 4, 10, 10, 10).beginning_of_day
+    with_env_tz "US/Eastern" do
+      assert_equal Time.local(2006, 4, 2, 0, 0, 0), Time.local(2006, 4, 2, 10, 10, 10).beginning_of_day, "start DST"
+      assert_equal Time.local(2006, 10, 29, 0, 0, 0), Time.local(2006, 10, 29, 10, 10, 10).beginning_of_day, "ends DST"
     end
-    with_env_tz 'NZ' do
-      assert_equal Time.local(2006,3,19,0,0,0), Time.local(2006,3,19,10,10,10).beginning_of_day, 'ends DST'
-      assert_equal Time.local(2006,10,1,0,0,0), Time.local(2006,10,1,10,10,10).beginning_of_day, 'start DST'
+    with_env_tz "NZ" do
+      assert_equal Time.local(2006, 3, 19, 0, 0, 0), Time.local(2006, 3, 19, 10, 10, 10).beginning_of_day, "ends DST"
+      assert_equal Time.local(2006, 10, 1, 0, 0, 0), Time.local(2006, 10, 1, 10, 10, 10).beginning_of_day, "start DST"
     end
   end
 
   def test_middle_of_day
-    assert_equal Time.local(2005,2,4,12,0,0), Time.local(2005,2,4,10,10,10).middle_of_day
-    with_env_tz 'US/Eastern' do
-      assert_equal Time.local(2006,4,2,12,0,0), Time.local(2006,4,2,10,10,10).middle_of_day, 'start DST'
-      assert_equal Time.local(2006,10,29,12,0,0), Time.local(2006,10,29,10,10,10).middle_of_day, 'ends DST'
+    assert_equal Time.local(2005, 2, 4, 12, 0, 0), Time.local(2005, 2, 4, 10, 10, 10).middle_of_day
+    with_env_tz "US/Eastern" do
+      assert_equal Time.local(2006, 4, 2, 12, 0, 0), Time.local(2006, 4, 2, 10, 10, 10).middle_of_day, "start DST"
+      assert_equal Time.local(2006, 10, 29, 12, 0, 0), Time.local(2006, 10, 29, 10, 10, 10).middle_of_day, "ends DST"
     end
-    with_env_tz 'NZ' do
-      assert_equal Time.local(2006,3,19,12,0,0), Time.local(2006,3,19,10,10,10).middle_of_day, 'ends DST'
-      assert_equal Time.local(2006,10,1,12,0,0), Time.local(2006,10,1,10,10,10).middle_of_day, 'start DST'
+    with_env_tz "NZ" do
+      assert_equal Time.local(2006, 3, 19, 12, 0, 0), Time.local(2006, 3, 19, 10, 10, 10).middle_of_day, "ends DST"
+      assert_equal Time.local(2006, 10, 1, 12, 0, 0), Time.local(2006, 10, 1, 10, 10, 10).middle_of_day, "start DST"
     end
   end
 
   def test_beginning_of_hour
-    assert_equal Time.local(2005,2,4,19,0,0), Time.local(2005,2,4,19,30,10).beginning_of_hour
+    assert_equal Time.local(2005, 2, 4, 19, 0, 0), Time.local(2005, 2, 4, 19, 30, 10).beginning_of_hour
   end
 
   def test_beginning_of_minute
-    assert_equal Time.local(2005,2,4,19,30,0), Time.local(2005,2,4,19,30,10).beginning_of_minute
+    assert_equal Time.local(2005, 2, 4, 19, 30, 0), Time.local(2005, 2, 4, 19, 30, 10).beginning_of_minute
   end
 
   def test_end_of_day
-    assert_equal Time.local(2007,8,12,23,59,59,Rational(999999999, 1000)), Time.local(2007,8,12,10,10,10).end_of_day
-    with_env_tz 'US/Eastern' do
-      assert_equal Time.local(2007,4,2,23,59,59,Rational(999999999, 1000)), Time.local(2007,4,2,10,10,10).end_of_day, 'start DST'
-      assert_equal Time.local(2007,10,29,23,59,59,Rational(999999999, 1000)), Time.local(2007,10,29,10,10,10).end_of_day, 'ends DST'
+    assert_equal Time.local(2007, 8, 12, 23, 59, 59, Rational(999999999, 1000)), Time.local(2007, 8, 12, 10, 10, 10).end_of_day
+    with_env_tz "US/Eastern" do
+      assert_equal Time.local(2007, 4, 2, 23, 59, 59, Rational(999999999, 1000)), Time.local(2007, 4, 2, 10, 10, 10).end_of_day, "start DST"
+      assert_equal Time.local(2007, 10, 29, 23, 59, 59, Rational(999999999, 1000)), Time.local(2007, 10, 29, 10, 10, 10).end_of_day, "ends DST"
     end
-    with_env_tz 'NZ' do
-      assert_equal Time.local(2006,3,19,23,59,59,Rational(999999999, 1000)), Time.local(2006,3,19,10,10,10).end_of_day, 'ends DST'
-      assert_equal Time.local(2006,10,1,23,59,59,Rational(999999999, 1000)), Time.local(2006,10,1,10,10,10).end_of_day, 'start DST'
+    with_env_tz "NZ" do
+      assert_equal Time.local(2006, 3, 19, 23, 59, 59, Rational(999999999, 1000)), Time.local(2006, 3, 19, 10, 10, 10).end_of_day, "ends DST"
+      assert_equal Time.local(2006, 10, 1, 23, 59, 59, Rational(999999999, 1000)), Time.local(2006, 10, 1, 10, 10, 10).end_of_day, "start DST"
     end
-    with_env_tz 'Asia/Yekaterinburg' do
-      assert_equal Time.local(2015, 2, 8, 23, 59, 59, Rational(999999999, 1000)), Time.new(2015, 2, 8, 8, 0, 0, '+05:00').end_of_day
+    with_env_tz "Asia/Yekaterinburg" do
+      assert_equal Time.local(2015, 2, 8, 23, 59, 59, Rational(999999999, 1000)), Time.new(2015, 2, 8, 8, 0, 0, "+05:00").end_of_day
     end
   end
 
   def test_end_of_hour
-    assert_equal Time.local(2005,2,4,19,59,59,Rational(999999999, 1000)), Time.local(2005,2,4,19,30,10).end_of_hour
+    assert_equal Time.local(2005, 2, 4, 19, 59, 59, Rational(999999999, 1000)), Time.local(2005, 2, 4, 19, 30, 10).end_of_hour
   end
 
   def test_end_of_minute
-    assert_equal Time.local(2005,2,4,19,30,59,Rational(999999999, 1000)), Time.local(2005,2,4,19,30,10).end_of_minute
-  end
-
-  def test_last_year
-    assert_equal Time.local(2004,6,5,10),  Time.local(2005,6,5,10,0,0).last_year
+    assert_equal Time.local(2005, 2, 4, 19, 30, 59, Rational(999999999, 1000)), Time.local(2005, 2, 4, 19, 30, 10).end_of_minute
   end
 
   def test_ago
-    assert_equal Time.local(2005,2,22,10,10,9),  Time.local(2005,2,22,10,10,10).ago(1)
-    assert_equal Time.local(2005,2,22,9,10,10),  Time.local(2005,2,22,10,10,10).ago(3600)
-    assert_equal Time.local(2005,2,20,10,10,10), Time.local(2005,2,22,10,10,10).ago(86400*2)
-    assert_equal Time.local(2005,2,20,9,9,45),   Time.local(2005,2,22,10,10,10).ago(86400*2 + 3600 + 25)
+    assert_equal Time.local(2005, 2, 22, 10, 10, 9),  Time.local(2005, 2, 22, 10, 10, 10).ago(1)
+    assert_equal Time.local(2005, 2, 22, 9, 10, 10),  Time.local(2005, 2, 22, 10, 10, 10).ago(3600)
+    assert_equal Time.local(2005, 2, 20, 10, 10, 10), Time.local(2005, 2, 22, 10, 10, 10).ago(86400 * 2)
+    assert_equal Time.local(2005, 2, 20, 9, 9, 45),   Time.local(2005, 2, 22, 10, 10, 10).ago(86400 * 2 + 3600 + 25)
   end
 
   def test_daylight_savings_time_crossings_backward_start
-    with_env_tz 'US/Eastern' do
+    with_env_tz "US/Eastern" do
       # dt: US: 2005 April 3rd 4:18am
-      assert_equal Time.local(2005,4,2,3,18,0), Time.local(2005,4,3,4,18,0).ago(24.hours), 'dt-24.hours=>st'
-      assert_equal Time.local(2005,4,2,3,18,0), Time.local(2005,4,3,4,18,0).ago(86400), 'dt-86400=>st'
-      assert_equal Time.local(2005,4,2,3,18,0), Time.local(2005,4,3,4,18,0).ago(86400.seconds), 'dt-86400.seconds=>st'
+      assert_equal Time.local(2005, 4, 2, 3, 18, 0), Time.local(2005, 4, 3, 4, 18, 0).ago(24.hours), "dt-24.hours=>st"
+      assert_equal Time.local(2005, 4, 2, 3, 18, 0), Time.local(2005, 4, 3, 4, 18, 0).ago(86400), "dt-86400=>st"
+      assert_equal Time.local(2005, 4, 2, 3, 18, 0), Time.local(2005, 4, 3, 4, 18, 0).ago(86400.seconds), "dt-86400.seconds=>st"
 
-      assert_equal Time.local(2005,4,1,4,18,0), Time.local(2005,4,2,4,18,0).ago(24.hours), 'st-24.hours=>st'
-      assert_equal Time.local(2005,4,1,4,18,0), Time.local(2005,4,2,4,18,0).ago(86400), 'st-86400=>st'
-      assert_equal Time.local(2005,4,1,4,18,0), Time.local(2005,4,2,4,18,0).ago(86400.seconds), 'st-86400.seconds=>st'
+      assert_equal Time.local(2005, 4, 1, 4, 18, 0), Time.local(2005, 4, 2, 4, 18, 0).ago(24.hours), "st-24.hours=>st"
+      assert_equal Time.local(2005, 4, 1, 4, 18, 0), Time.local(2005, 4, 2, 4, 18, 0).ago(86400), "st-86400=>st"
+      assert_equal Time.local(2005, 4, 1, 4, 18, 0), Time.local(2005, 4, 2, 4, 18, 0).ago(86400.seconds), "st-86400.seconds=>st"
     end
-    with_env_tz 'NZ' do
+    with_env_tz "NZ" do
       # dt: New Zealand: 2006 October 1st 4:18am
-      assert_equal Time.local(2006,9,30,3,18,0), Time.local(2006,10,1,4,18,0).ago(24.hours), 'dt-24.hours=>st'
-      assert_equal Time.local(2006,9,30,3,18,0), Time.local(2006,10,1,4,18,0).ago(86400), 'dt-86400=>st'
-      assert_equal Time.local(2006,9,30,3,18,0), Time.local(2006,10,1,4,18,0).ago(86400.seconds), 'dt-86400.seconds=>st'
+      assert_equal Time.local(2006, 9, 30, 3, 18, 0), Time.local(2006, 10, 1, 4, 18, 0).ago(24.hours), "dt-24.hours=>st"
+      assert_equal Time.local(2006, 9, 30, 3, 18, 0), Time.local(2006, 10, 1, 4, 18, 0).ago(86400), "dt-86400=>st"
+      assert_equal Time.local(2006, 9, 30, 3, 18, 0), Time.local(2006, 10, 1, 4, 18, 0).ago(86400.seconds), "dt-86400.seconds=>st"
 
-      assert_equal Time.local(2006,9,29,4,18,0), Time.local(2006,9,30,4,18,0).ago(24.hours), 'st-24.hours=>st'
-      assert_equal Time.local(2006,9,29,4,18,0), Time.local(2006,9,30,4,18,0).ago(86400), 'st-86400=>st'
-      assert_equal Time.local(2006,9,29,4,18,0), Time.local(2006,9,30,4,18,0).ago(86400.seconds), 'st-86400.seconds=>st'
+      assert_equal Time.local(2006, 9, 29, 4, 18, 0), Time.local(2006, 9, 30, 4, 18, 0).ago(24.hours), "st-24.hours=>st"
+      assert_equal Time.local(2006, 9, 29, 4, 18, 0), Time.local(2006, 9, 30, 4, 18, 0).ago(86400), "st-86400=>st"
+      assert_equal Time.local(2006, 9, 29, 4, 18, 0), Time.local(2006, 9, 30, 4, 18, 0).ago(86400.seconds), "st-86400.seconds=>st"
     end
   end
 
   def test_daylight_savings_time_crossings_backward_end
-    with_env_tz 'US/Eastern' do
+    with_env_tz "US/Eastern" do
       # st: US: 2005 October 30th 4:03am
-      assert_equal Time.local(2005,10,29,5,3), Time.local(2005,10,30,4,3,0).ago(24.hours), 'st-24.hours=>dt'
-      assert_equal Time.local(2005,10,29,5,3), Time.local(2005,10,30,4,3,0).ago(86400), 'st-86400=>dt'
-      assert_equal Time.local(2005,10,29,5,3), Time.local(2005,10,30,4,3,0).ago(86400.seconds), 'st-86400.seconds=>dt'
+      assert_equal Time.local(2005, 10, 29, 5, 3), Time.local(2005, 10, 30, 4, 3, 0).ago(24.hours), "st-24.hours=>dt"
+      assert_equal Time.local(2005, 10, 29, 5, 3), Time.local(2005, 10, 30, 4, 3, 0).ago(86400), "st-86400=>dt"
+      assert_equal Time.local(2005, 10, 29, 5, 3), Time.local(2005, 10, 30, 4, 3, 0).ago(86400.seconds), "st-86400.seconds=>dt"
 
-      assert_equal Time.local(2005,10,28,4,3), Time.local(2005,10,29,4,3,0).ago(24.hours), 'dt-24.hours=>dt'
-      assert_equal Time.local(2005,10,28,4,3), Time.local(2005,10,29,4,3,0).ago(86400), 'dt-86400=>dt'
-      assert_equal Time.local(2005,10,28,4,3), Time.local(2005,10,29,4,3,0).ago(86400.seconds), 'dt-86400.seconds=>dt'
+      assert_equal Time.local(2005, 10, 28, 4, 3), Time.local(2005, 10, 29, 4, 3, 0).ago(24.hours), "dt-24.hours=>dt"
+      assert_equal Time.local(2005, 10, 28, 4, 3), Time.local(2005, 10, 29, 4, 3, 0).ago(86400), "dt-86400=>dt"
+      assert_equal Time.local(2005, 10, 28, 4, 3), Time.local(2005, 10, 29, 4, 3, 0).ago(86400.seconds), "dt-86400.seconds=>dt"
     end
-    with_env_tz 'NZ' do
+    with_env_tz "NZ" do
       # st: New Zealand: 2006 March 19th 4:03am
-      assert_equal Time.local(2006,3,18,5,3), Time.local(2006,3,19,4,3,0).ago(24.hours), 'st-24.hours=>dt'
-      assert_equal Time.local(2006,3,18,5,3), Time.local(2006,3,19,4,3,0).ago(86400), 'st-86400=>dt'
-      assert_equal Time.local(2006,3,18,5,3), Time.local(2006,3,19,4,3,0).ago(86400.seconds), 'st-86400.seconds=>dt'
+      assert_equal Time.local(2006, 3, 18, 5, 3), Time.local(2006, 3, 19, 4, 3, 0).ago(24.hours), "st-24.hours=>dt"
+      assert_equal Time.local(2006, 3, 18, 5, 3), Time.local(2006, 3, 19, 4, 3, 0).ago(86400), "st-86400=>dt"
+      assert_equal Time.local(2006, 3, 18, 5, 3), Time.local(2006, 3, 19, 4, 3, 0).ago(86400.seconds), "st-86400.seconds=>dt"
 
-      assert_equal Time.local(2006,3,17,4,3), Time.local(2006,3,18,4,3,0).ago(24.hours), 'dt-24.hours=>dt'
-      assert_equal Time.local(2006,3,17,4,3), Time.local(2006,3,18,4,3,0).ago(86400), 'dt-86400=>dt'
-      assert_equal Time.local(2006,3,17,4,3), Time.local(2006,3,18,4,3,0).ago(86400.seconds), 'dt-86400.seconds=>dt'
+      assert_equal Time.local(2006, 3, 17, 4, 3), Time.local(2006, 3, 18, 4, 3, 0).ago(24.hours), "dt-24.hours=>dt"
+      assert_equal Time.local(2006, 3, 17, 4, 3), Time.local(2006, 3, 18, 4, 3, 0).ago(86400), "dt-86400=>dt"
+      assert_equal Time.local(2006, 3, 17, 4, 3), Time.local(2006, 3, 18, 4, 3, 0).ago(86400.seconds), "dt-86400.seconds=>dt"
     end
   end
 
   def test_daylight_savings_time_crossings_backward_start_1day
-    with_env_tz 'US/Eastern' do
+    with_env_tz "US/Eastern" do
       # dt: US: 2005 April 3rd 4:18am
-      assert_equal Time.local(2005,4,2,4,18,0), Time.local(2005,4,3,4,18,0).ago(1.day), 'dt-1.day=>st'
-      assert_equal Time.local(2005,4,1,4,18,0), Time.local(2005,4,2,4,18,0).ago(1.day), 'st-1.day=>st'
+      assert_equal Time.local(2005, 4, 2, 4, 18, 0), Time.local(2005, 4, 3, 4, 18, 0).ago(1.day), "dt-1.day=>st"
+      assert_equal Time.local(2005, 4, 1, 4, 18, 0), Time.local(2005, 4, 2, 4, 18, 0).ago(1.day), "st-1.day=>st"
     end
-    with_env_tz 'NZ' do
+    with_env_tz "NZ" do
       # dt: New Zealand: 2006 October 1st 4:18am
-      assert_equal Time.local(2006,9,30,4,18,0), Time.local(2006,10,1,4,18,0).ago(1.day), 'dt-1.day=>st'
-      assert_equal Time.local(2006,9,29,4,18,0), Time.local(2006,9,30,4,18,0).ago(1.day), 'st-1.day=>st'
+      assert_equal Time.local(2006, 9, 30, 4, 18, 0), Time.local(2006, 10, 1, 4, 18, 0).ago(1.day), "dt-1.day=>st"
+      assert_equal Time.local(2006, 9, 29, 4, 18, 0), Time.local(2006, 9, 30, 4, 18, 0).ago(1.day), "st-1.day=>st"
     end
   end
 
   def test_daylight_savings_time_crossings_backward_end_1day
-    with_env_tz 'US/Eastern' do
+    with_env_tz "US/Eastern" do
       # st: US: 2005 October 30th 4:03am
-      assert_equal Time.local(2005,10,29,4,3), Time.local(2005,10,30,4,3,0).ago(1.day), 'st-1.day=>dt'
-      assert_equal Time.local(2005,10,28,4,3), Time.local(2005,10,29,4,3,0).ago(1.day), 'dt-1.day=>dt'
+      assert_equal Time.local(2005, 10, 29, 4, 3), Time.local(2005, 10, 30, 4, 3, 0).ago(1.day), "st-1.day=>dt"
+      assert_equal Time.local(2005, 10, 28, 4, 3), Time.local(2005, 10, 29, 4, 3, 0).ago(1.day), "dt-1.day=>dt"
     end
-    with_env_tz 'NZ' do
+    with_env_tz "NZ" do
       # st: New Zealand: 2006 March 19th 4:03am
-      assert_equal Time.local(2006,3,18,4,3), Time.local(2006,3,19,4,3,0).ago(1.day), 'st-1.day=>dt'
-      assert_equal Time.local(2006,3,17,4,3), Time.local(2006,3,18,4,3,0).ago(1.day), 'dt-1.day=>dt'
+      assert_equal Time.local(2006, 3, 18, 4, 3), Time.local(2006, 3, 19, 4, 3, 0).ago(1.day), "st-1.day=>dt"
+      assert_equal Time.local(2006, 3, 17, 4, 3), Time.local(2006, 3, 18, 4, 3, 0).ago(1.day), "dt-1.day=>dt"
     end
   end
 
   def test_since
-    assert_equal Time.local(2005,2,22,10,10,11), Time.local(2005,2,22,10,10,10).since(1)
-    assert_equal Time.local(2005,2,22,11,10,10), Time.local(2005,2,22,10,10,10).since(3600)
-    assert_equal Time.local(2005,2,24,10,10,10), Time.local(2005,2,22,10,10,10).since(86400*2)
-    assert_equal Time.local(2005,2,24,11,10,35), Time.local(2005,2,22,10,10,10).since(86400*2 + 3600 + 25)
+    assert_equal Time.local(2005, 2, 22, 10, 10, 11), Time.local(2005, 2, 22, 10, 10, 10).since(1)
+    assert_equal Time.local(2005, 2, 22, 11, 10, 10), Time.local(2005, 2, 22, 10, 10, 10).since(3600)
+    assert_equal Time.local(2005, 2, 24, 10, 10, 10), Time.local(2005, 2, 22, 10, 10, 10).since(86400 * 2)
+    assert_equal Time.local(2005, 2, 24, 11, 10, 35), Time.local(2005, 2, 22, 10, 10, 10).since(86400 * 2 + 3600 + 25)
     # when out of range of Time, returns a DateTime
-    assert_equal DateTime.civil(2038,1,20,11,59,59), Time.utc(2038,1,18,11,59,59).since(86400*2)
+    assert_equal DateTime.civil(2038, 1, 20, 11, 59, 59), Time.utc(2038, 1, 18, 11, 59, 59).since(86400 * 2)
   end
 
   def test_daylight_savings_time_crossings_forward_start
-    with_env_tz 'US/Eastern' do
+    with_env_tz "US/Eastern" do
       # st: US: 2005 April 2nd 7:27pm
-      assert_equal Time.local(2005,4,3,20,27,0), Time.local(2005,4,2,19,27,0).since(24.hours), 'st+24.hours=>dt'
-      assert_equal Time.local(2005,4,3,20,27,0), Time.local(2005,4,2,19,27,0).since(86400), 'st+86400=>dt'
-      assert_equal Time.local(2005,4,3,20,27,0), Time.local(2005,4,2,19,27,0).since(86400.seconds), 'st+86400.seconds=>dt'
+      assert_equal Time.local(2005, 4, 3, 20, 27, 0), Time.local(2005, 4, 2, 19, 27, 0).since(24.hours), "st+24.hours=>dt"
+      assert_equal Time.local(2005, 4, 3, 20, 27, 0), Time.local(2005, 4, 2, 19, 27, 0).since(86400), "st+86400=>dt"
+      assert_equal Time.local(2005, 4, 3, 20, 27, 0), Time.local(2005, 4, 2, 19, 27, 0).since(86400.seconds), "st+86400.seconds=>dt"
 
-      assert_equal Time.local(2005,4,4,19,27,0), Time.local(2005,4,3,19,27,0).since(24.hours), 'dt+24.hours=>dt'
-      assert_equal Time.local(2005,4,4,19,27,0), Time.local(2005,4,3,19,27,0).since(86400), 'dt+86400=>dt'
-      assert_equal Time.local(2005,4,4,19,27,0), Time.local(2005,4,3,19,27,0).since(86400.seconds), 'dt+86400.seconds=>dt'
+      assert_equal Time.local(2005, 4, 4, 19, 27, 0), Time.local(2005, 4, 3, 19, 27, 0).since(24.hours), "dt+24.hours=>dt"
+      assert_equal Time.local(2005, 4, 4, 19, 27, 0), Time.local(2005, 4, 3, 19, 27, 0).since(86400), "dt+86400=>dt"
+      assert_equal Time.local(2005, 4, 4, 19, 27, 0), Time.local(2005, 4, 3, 19, 27, 0).since(86400.seconds), "dt+86400.seconds=>dt"
     end
-    with_env_tz 'NZ' do
+    with_env_tz "NZ" do
       # st: New Zealand: 2006 September 30th 7:27pm
-      assert_equal Time.local(2006,10,1,20,27,0), Time.local(2006,9,30,19,27,0).since(24.hours), 'st+24.hours=>dt'
-      assert_equal Time.local(2006,10,1,20,27,0), Time.local(2006,9,30,19,27,0).since(86400), 'st+86400=>dt'
-      assert_equal Time.local(2006,10,1,20,27,0), Time.local(2006,9,30,19,27,0).since(86400.seconds), 'st+86400.seconds=>dt'
+      assert_equal Time.local(2006, 10, 1, 20, 27, 0), Time.local(2006, 9, 30, 19, 27, 0).since(24.hours), "st+24.hours=>dt"
+      assert_equal Time.local(2006, 10, 1, 20, 27, 0), Time.local(2006, 9, 30, 19, 27, 0).since(86400), "st+86400=>dt"
+      assert_equal Time.local(2006, 10, 1, 20, 27, 0), Time.local(2006, 9, 30, 19, 27, 0).since(86400.seconds), "st+86400.seconds=>dt"
 
-      assert_equal Time.local(2006,10,2,19,27,0), Time.local(2006,10,1,19,27,0).since(24.hours), 'dt+24.hours=>dt'
-      assert_equal Time.local(2006,10,2,19,27,0), Time.local(2006,10,1,19,27,0).since(86400), 'dt+86400=>dt'
-      assert_equal Time.local(2006,10,2,19,27,0), Time.local(2006,10,1,19,27,0).since(86400.seconds), 'dt+86400.seconds=>dt'
+      assert_equal Time.local(2006, 10, 2, 19, 27, 0), Time.local(2006, 10, 1, 19, 27, 0).since(24.hours), "dt+24.hours=>dt"
+      assert_equal Time.local(2006, 10, 2, 19, 27, 0), Time.local(2006, 10, 1, 19, 27, 0).since(86400), "dt+86400=>dt"
+      assert_equal Time.local(2006, 10, 2, 19, 27, 0), Time.local(2006, 10, 1, 19, 27, 0).since(86400.seconds), "dt+86400.seconds=>dt"
     end
   end
 
   def test_daylight_savings_time_crossings_forward_start_1day
-    with_env_tz 'US/Eastern' do
+    with_env_tz "US/Eastern" do
       # st: US: 2005 April 2nd 7:27pm
-      assert_equal Time.local(2005,4,3,19,27,0), Time.local(2005,4,2,19,27,0).since(1.day), 'st+1.day=>dt'
-      assert_equal Time.local(2005,4,4,19,27,0), Time.local(2005,4,3,19,27,0).since(1.day), 'dt+1.day=>dt'
+      assert_equal Time.local(2005, 4, 3, 19, 27, 0), Time.local(2005, 4, 2, 19, 27, 0).since(1.day), "st+1.day=>dt"
+      assert_equal Time.local(2005, 4, 4, 19, 27, 0), Time.local(2005, 4, 3, 19, 27, 0).since(1.day), "dt+1.day=>dt"
     end
-    with_env_tz 'NZ' do
+    with_env_tz "NZ" do
       # st: New Zealand: 2006 September 30th 7:27pm
-      assert_equal Time.local(2006,10,1,19,27,0), Time.local(2006,9,30,19,27,0).since(1.day), 'st+1.day=>dt'
-      assert_equal Time.local(2006,10,2,19,27,0), Time.local(2006,10,1,19,27,0).since(1.day), 'dt+1.day=>dt'
+      assert_equal Time.local(2006, 10, 1, 19, 27, 0), Time.local(2006, 9, 30, 19, 27, 0).since(1.day), "st+1.day=>dt"
+      assert_equal Time.local(2006, 10, 2, 19, 27, 0), Time.local(2006, 10, 1, 19, 27, 0).since(1.day), "dt+1.day=>dt"
     end
   end
 
   def test_daylight_savings_time_crossings_forward_start_tomorrow
-    with_env_tz 'US/Eastern' do
+    with_env_tz "US/Eastern" do
       # st: US: 2005 April 2nd 7:27pm
-      assert_equal Time.local(2005,4,3,19,27,0), Time.local(2005,4,2,19,27,0).tomorrow, 'st+1.day=>dt'
-      assert_equal Time.local(2005,4,4,19,27,0), Time.local(2005,4,3,19,27,0).tomorrow, 'dt+1.day=>dt'
+      assert_equal Time.local(2005, 4, 3, 19, 27, 0), Time.local(2005, 4, 2, 19, 27, 0).tomorrow, "st+1.day=>dt"
+      assert_equal Time.local(2005, 4, 4, 19, 27, 0), Time.local(2005, 4, 3, 19, 27, 0).tomorrow, "dt+1.day=>dt"
     end
-    with_env_tz 'NZ' do
+    with_env_tz "NZ" do
       # st: New Zealand: 2006 September 30th 7:27pm
-      assert_equal Time.local(2006,10,1,19,27,0), Time.local(2006,9,30,19,27,0).tomorrow, 'st+1.day=>dt'
-      assert_equal Time.local(2006,10,2,19,27,0), Time.local(2006,10,1,19,27,0).tomorrow, 'dt+1.day=>dt'
+      assert_equal Time.local(2006, 10, 1, 19, 27, 0), Time.local(2006, 9, 30, 19, 27, 0).tomorrow, "st+1.day=>dt"
+      assert_equal Time.local(2006, 10, 2, 19, 27, 0), Time.local(2006, 10, 1, 19, 27, 0).tomorrow, "dt+1.day=>dt"
     end
   end
 
   def test_daylight_savings_time_crossings_backward_start_yesterday
-    with_env_tz 'US/Eastern' do
+    with_env_tz "US/Eastern" do
       # st: US: 2005 April 2nd 7:27pm
-      assert_equal Time.local(2005,4,2,19,27,0), Time.local(2005,4,3,19,27,0).yesterday, 'dt-1.day=>st'
-      assert_equal Time.local(2005,4,3,19,27,0), Time.local(2005,4,4,19,27,0).yesterday, 'dt-1.day=>dt'
+      assert_equal Time.local(2005, 4, 2, 19, 27, 0), Time.local(2005, 4, 3, 19, 27, 0).yesterday, "dt-1.day=>st"
+      assert_equal Time.local(2005, 4, 3, 19, 27, 0), Time.local(2005, 4, 4, 19, 27, 0).yesterday, "dt-1.day=>dt"
     end
-    with_env_tz 'NZ' do
+    with_env_tz "NZ" do
       # st: New Zealand: 2006 September 30th 7:27pm
-      assert_equal Time.local(2006,9,30,19,27,0), Time.local(2006,10,1,19,27,0).yesterday, 'dt-1.day=>st'
-      assert_equal Time.local(2006,10,1,19,27,0), Time.local(2006,10,2,19,27,0).yesterday, 'dt-1.day=>dt'
+      assert_equal Time.local(2006, 9, 30, 19, 27, 0), Time.local(2006, 10, 1, 19, 27, 0).yesterday, "dt-1.day=>st"
+      assert_equal Time.local(2006, 10, 1, 19, 27, 0), Time.local(2006, 10, 2, 19, 27, 0).yesterday, "dt-1.day=>dt"
     end
   end
 
   def test_daylight_savings_time_crossings_forward_end
-    with_env_tz 'US/Eastern' do
+    with_env_tz "US/Eastern" do
       # dt: US: 2005 October 30th 12:45am
-      assert_equal Time.local(2005,10,30,23,45,0), Time.local(2005,10,30,0,45,0).since(24.hours), 'dt+24.hours=>st'
-      assert_equal Time.local(2005,10,30,23,45,0), Time.local(2005,10,30,0,45,0).since(86400), 'dt+86400=>st'
-      assert_equal Time.local(2005,10,30,23,45,0), Time.local(2005,10,30,0,45,0).since(86400.seconds), 'dt+86400.seconds=>st'
+      assert_equal Time.local(2005, 10, 30, 23, 45, 0), Time.local(2005, 10, 30, 0, 45, 0).since(24.hours), "dt+24.hours=>st"
+      assert_equal Time.local(2005, 10, 30, 23, 45, 0), Time.local(2005, 10, 30, 0, 45, 0).since(86400), "dt+86400=>st"
+      assert_equal Time.local(2005, 10, 30, 23, 45, 0), Time.local(2005, 10, 30, 0, 45, 0).since(86400.seconds), "dt+86400.seconds=>st"
 
-      assert_equal Time.local(2005,11, 1,0,45,0), Time.local(2005,10,31,0,45,0).since(24.hours), 'st+24.hours=>st'
-      assert_equal Time.local(2005,11, 1,0,45,0), Time.local(2005,10,31,0,45,0).since(86400), 'st+86400=>st'
-      assert_equal Time.local(2005,11, 1,0,45,0), Time.local(2005,10,31,0,45,0).since(86400.seconds), 'st+86400.seconds=>st'
+      assert_equal Time.local(2005, 11, 1, 0, 45, 0), Time.local(2005, 10, 31, 0, 45, 0).since(24.hours), "st+24.hours=>st"
+      assert_equal Time.local(2005, 11, 1, 0, 45, 0), Time.local(2005, 10, 31, 0, 45, 0).since(86400), "st+86400=>st"
+      assert_equal Time.local(2005, 11, 1, 0, 45, 0), Time.local(2005, 10, 31, 0, 45, 0).since(86400.seconds), "st+86400.seconds=>st"
     end
-    with_env_tz 'NZ' do
+    with_env_tz "NZ" do
       # dt: New Zealand: 2006 March 19th 1:45am
-      assert_equal Time.local(2006,3,20,0,45,0), Time.local(2006,3,19,1,45,0).since(24.hours), 'dt+24.hours=>st'
-      assert_equal Time.local(2006,3,20,0,45,0), Time.local(2006,3,19,1,45,0).since(86400), 'dt+86400=>st'
-      assert_equal Time.local(2006,3,20,0,45,0), Time.local(2006,3,19,1,45,0).since(86400.seconds), 'dt+86400.seconds=>st'
+      assert_equal Time.local(2006, 3, 20, 0, 45, 0), Time.local(2006, 3, 19, 1, 45, 0).since(24.hours), "dt+24.hours=>st"
+      assert_equal Time.local(2006, 3, 20, 0, 45, 0), Time.local(2006, 3, 19, 1, 45, 0).since(86400), "dt+86400=>st"
+      assert_equal Time.local(2006, 3, 20, 0, 45, 0), Time.local(2006, 3, 19, 1, 45, 0).since(86400.seconds), "dt+86400.seconds=>st"
 
-      assert_equal Time.local(2006,3,21,1,45,0), Time.local(2006,3,20,1,45,0).since(24.hours), 'st+24.hours=>st'
-      assert_equal Time.local(2006,3,21,1,45,0), Time.local(2006,3,20,1,45,0).since(86400), 'st+86400=>st'
-      assert_equal Time.local(2006,3,21,1,45,0), Time.local(2006,3,20,1,45,0).since(86400.seconds), 'st+86400.seconds=>st'
+      assert_equal Time.local(2006, 3, 21, 1, 45, 0), Time.local(2006, 3, 20, 1, 45, 0).since(24.hours), "st+24.hours=>st"
+      assert_equal Time.local(2006, 3, 21, 1, 45, 0), Time.local(2006, 3, 20, 1, 45, 0).since(86400), "st+86400=>st"
+      assert_equal Time.local(2006, 3, 21, 1, 45, 0), Time.local(2006, 3, 20, 1, 45, 0).since(86400.seconds), "st+86400.seconds=>st"
     end
   end
 
   def test_daylight_savings_time_crossings_forward_end_1day
-    with_env_tz 'US/Eastern' do
+    with_env_tz "US/Eastern" do
       # dt: US: 2005 October 30th 12:45am
-      assert_equal Time.local(2005,10,31,0,45,0), Time.local(2005,10,30,0,45,0).since(1.day), 'dt+1.day=>st'
-      assert_equal Time.local(2005,11, 1,0,45,0), Time.local(2005,10,31,0,45,0).since(1.day), 'st+1.day=>st'
+      assert_equal Time.local(2005, 10, 31, 0, 45, 0), Time.local(2005, 10, 30, 0, 45, 0).since(1.day), "dt+1.day=>st"
+      assert_equal Time.local(2005, 11, 1, 0, 45, 0), Time.local(2005, 10, 31, 0, 45, 0).since(1.day), "st+1.day=>st"
     end
-    with_env_tz 'NZ' do
+    with_env_tz "NZ" do
       # dt: New Zealand: 2006 March 19th 1:45am
-      assert_equal Time.local(2006,3,20,1,45,0), Time.local(2006,3,19,1,45,0).since(1.day), 'dt+1.day=>st'
-      assert_equal Time.local(2006,3,21,1,45,0), Time.local(2006,3,20,1,45,0).since(1.day), 'st+1.day=>st'
+      assert_equal Time.local(2006, 3, 20, 1, 45, 0), Time.local(2006, 3, 19, 1, 45, 0).since(1.day), "dt+1.day=>st"
+      assert_equal Time.local(2006, 3, 21, 1, 45, 0), Time.local(2006, 3, 20, 1, 45, 0).since(1.day), "st+1.day=>st"
     end
   end
 
   def test_daylight_savings_time_crossings_forward_end_tomorrow
-    with_env_tz 'US/Eastern' do
+    with_env_tz "US/Eastern" do
       # dt: US: 2005 October 30th 12:45am
-      assert_equal Time.local(2005,10,31,0,45,0), Time.local(2005,10,30,0,45,0).tomorrow, 'dt+1.day=>st'
-      assert_equal Time.local(2005,11, 1,0,45,0), Time.local(2005,10,31,0,45,0).tomorrow, 'st+1.day=>st'
+      assert_equal Time.local(2005, 10, 31, 0, 45, 0), Time.local(2005, 10, 30, 0, 45, 0).tomorrow, "dt+1.day=>st"
+      assert_equal Time.local(2005, 11, 1, 0, 45, 0), Time.local(2005, 10, 31, 0, 45, 0).tomorrow, "st+1.day=>st"
     end
-    with_env_tz 'NZ' do
+    with_env_tz "NZ" do
       # dt: New Zealand: 2006 March 19th 1:45am
-      assert_equal Time.local(2006,3,20,1,45,0), Time.local(2006,3,19,1,45,0).tomorrow, 'dt+1.day=>st'
-      assert_equal Time.local(2006,3,21,1,45,0), Time.local(2006,3,20,1,45,0).tomorrow, 'st+1.day=>st'
+      assert_equal Time.local(2006, 3, 20, 1, 45, 0), Time.local(2006, 3, 19, 1, 45, 0).tomorrow, "dt+1.day=>st"
+      assert_equal Time.local(2006, 3, 21, 1, 45, 0), Time.local(2006, 3, 20, 1, 45, 0).tomorrow, "st+1.day=>st"
     end
   end
 
   def test_daylight_savings_time_crossings_backward_end_yesterday
-    with_env_tz 'US/Eastern' do
+    with_env_tz "US/Eastern" do
       # dt: US: 2005 October 30th 12:45am
-      assert_equal Time.local(2005,10,30,0,45,0), Time.local(2005,10,31,0,45,0).yesterday, 'st-1.day=>dt'
-      assert_equal Time.local(2005,10, 31,0,45,0), Time.local(2005,11,1,0,45,0).yesterday, 'st-1.day=>st'
+      assert_equal Time.local(2005, 10, 30, 0, 45, 0), Time.local(2005, 10, 31, 0, 45, 0).yesterday, "st-1.day=>dt"
+      assert_equal Time.local(2005, 10, 31, 0, 45, 0), Time.local(2005, 11, 1, 0, 45, 0).yesterday, "st-1.day=>st"
     end
-    with_env_tz 'NZ' do
+    with_env_tz "NZ" do
       # dt: New Zealand: 2006 March 19th 1:45am
-      assert_equal Time.local(2006,3,19,1,45,0), Time.local(2006,3,20,1,45,0).yesterday, 'st-1.day=>dt'
-      assert_equal Time.local(2006,3,20,1,45,0), Time.local(2006,3,21,1,45,0).yesterday, 'st-1.day=>st'
+      assert_equal Time.local(2006, 3, 19, 1, 45, 0), Time.local(2006, 3, 20, 1, 45, 0).yesterday, "st-1.day=>dt"
+      assert_equal Time.local(2006, 3, 20, 1, 45, 0), Time.local(2006, 3, 21, 1, 45, 0).yesterday, "st-1.day=>st"
     end
   end
 
   def test_change
-    assert_equal Time.local(2006,2,22,15,15,10), Time.local(2005,2,22,15,15,10).change(:year => 2006)
-    assert_equal Time.local(2005,6,22,15,15,10), Time.local(2005,2,22,15,15,10).change(:month => 6)
-    assert_equal Time.local(2012,9,22,15,15,10), Time.local(2005,2,22,15,15,10).change(:year => 2012, :month => 9)
-    assert_equal Time.local(2005,2,22,16),       Time.local(2005,2,22,15,15,10).change(:hour => 16)
-    assert_equal Time.local(2005,2,22,16,45),    Time.local(2005,2,22,15,15,10).change(:hour => 16, :min => 45)
-    assert_equal Time.local(2005,2,22,15,45),    Time.local(2005,2,22,15,15,10).change(:min => 45)
-
-    assert_equal Time.local(2005,1,2, 5, 0, 0, 0), Time.local(2005,1,2,11,22,33,44).change(:hour => 5)
-    assert_equal Time.local(2005,1,2,11, 6, 0, 0), Time.local(2005,1,2,11,22,33,44).change(:min  => 6)
-    assert_equal Time.local(2005,1,2,11,22, 7, 0), Time.local(2005,1,2,11,22,33,44).change(:sec  => 7)
-    assert_equal Time.local(2005,1,2,11,22,33, 8), Time.local(2005,1,2,11,22,33,44).change(:usec => 8)
-    assert_equal Time.local(2005,1,2,11,22,33, 8), Time.local(2005,1,2,11,22,33,2).change(:nsec => 8000)
-    assert_raise(ArgumentError) { Time.local(2005,1,2,11,22,33, 8).change(:usec => 1, :nsec => 1) }
-    assert_nothing_raised { Time.new(2015, 5, 9, 10, 00, 00, '+03:00').change(nsec: 999999999) }
+    assert_equal Time.local(2006, 2, 22, 15, 15, 10), Time.local(2005, 2, 22, 15, 15, 10).change(year: 2006)
+    assert_equal Time.local(2005, 6, 22, 15, 15, 10), Time.local(2005, 2, 22, 15, 15, 10).change(month: 6)
+    assert_equal Time.local(2012, 9, 22, 15, 15, 10), Time.local(2005, 2, 22, 15, 15, 10).change(year: 2012, month: 9)
+    assert_equal Time.local(2005, 2, 22, 16),       Time.local(2005, 2, 22, 15, 15, 10).change(hour: 16)
+    assert_equal Time.local(2005, 2, 22, 16, 45),    Time.local(2005, 2, 22, 15, 15, 10).change(hour: 16, min: 45)
+    assert_equal Time.local(2005, 2, 22, 15, 45),    Time.local(2005, 2, 22, 15, 15, 10).change(min: 45)
+
+    assert_equal Time.local(2005, 1, 2, 5, 0, 0, 0), Time.local(2005, 1, 2, 11, 22, 33, 44).change(hour: 5)
+    assert_equal Time.local(2005, 1, 2, 11, 6, 0, 0), Time.local(2005, 1, 2, 11, 22, 33, 44).change(min: 6)
+    assert_equal Time.local(2005, 1, 2, 11, 22, 7, 0), Time.local(2005, 1, 2, 11, 22, 33, 44).change(sec: 7)
+    assert_equal Time.local(2005, 1, 2, 11, 22, 33, 8), Time.local(2005, 1, 2, 11, 22, 33, 44).change(usec: 8)
+    assert_equal Time.local(2005, 1, 2, 11, 22, 33, 8), Time.local(2005, 1, 2, 11, 22, 33, 2).change(nsec: 8000)
+    assert_raise(ArgumentError) { Time.local(2005, 1, 2, 11, 22, 33, 8).change(usec: 1, nsec: 1) }
+    assert_nothing_raised { Time.new(2015, 5, 9, 10, 00, 00, "+03:00").change(nsec: 999999999) }
   end
 
   def test_utc_change
-    assert_equal Time.utc(2006,2,22,15,15,10), Time.utc(2005,2,22,15,15,10).change(:year => 2006)
-    assert_equal Time.utc(2005,6,22,15,15,10), Time.utc(2005,2,22,15,15,10).change(:month => 6)
-    assert_equal Time.utc(2012,9,22,15,15,10), Time.utc(2005,2,22,15,15,10).change(:year => 2012, :month => 9)
-    assert_equal Time.utc(2005,2,22,16),       Time.utc(2005,2,22,15,15,10).change(:hour => 16)
-    assert_equal Time.utc(2005,2,22,16,45),    Time.utc(2005,2,22,15,15,10).change(:hour => 16, :min => 45)
-    assert_equal Time.utc(2005,2,22,15,45),    Time.utc(2005,2,22,15,15,10).change(:min => 45)
-    assert_equal Time.utc(2005,1,2,11,22,33,8), Time.utc(2005,1,2,11,22,33,2).change(:nsec => 8000)
+    assert_equal Time.utc(2006, 2, 22, 15, 15, 10), Time.utc(2005, 2, 22, 15, 15, 10).change(year: 2006)
+    assert_equal Time.utc(2005, 6, 22, 15, 15, 10), Time.utc(2005, 2, 22, 15, 15, 10).change(month: 6)
+    assert_equal Time.utc(2012, 9, 22, 15, 15, 10), Time.utc(2005, 2, 22, 15, 15, 10).change(year: 2012, month: 9)
+    assert_equal Time.utc(2005, 2, 22, 16),       Time.utc(2005, 2, 22, 15, 15, 10).change(hour: 16)
+    assert_equal Time.utc(2005, 2, 22, 16, 45),    Time.utc(2005, 2, 22, 15, 15, 10).change(hour: 16, min: 45)
+    assert_equal Time.utc(2005, 2, 22, 15, 45),    Time.utc(2005, 2, 22, 15, 15, 10).change(min: 45)
+    assert_equal Time.utc(2005, 1, 2, 11, 22, 33, 8), Time.utc(2005, 1, 2, 11, 22, 33, 2).change(nsec: 8000)
   end
 
   def test_offset_change
-    assert_equal Time.new(2006,2,22,15,15,10,"-08:00"), Time.new(2005,2,22,15,15,10,"-08:00").change(:year => 2006)
-    assert_equal Time.new(2005,6,22,15,15,10,"-08:00"), Time.new(2005,2,22,15,15,10,"-08:00").change(:month => 6)
-    assert_equal Time.new(2012,9,22,15,15,10,"-08:00"), Time.new(2005,2,22,15,15,10,"-08:00").change(:year => 2012, :month => 9)
-    assert_equal Time.new(2005,2,22,16,0,0,"-08:00"),   Time.new(2005,2,22,15,15,10,"-08:00").change(:hour => 16)
-    assert_equal Time.new(2005,2,22,16,45,0,"-08:00"),  Time.new(2005,2,22,15,15,10,"-08:00").change(:hour => 16, :min => 45)
-    assert_equal Time.new(2005,2,22,15,45,0,"-08:00"),  Time.new(2005,2,22,15,15,10,"-08:00").change(:min => 45)
-    assert_equal Time.new(2005,2,22,15,15,10,"-08:00"),  Time.new(2005,2,22,15,15,0,"-08:00").change(:sec => 10)
-    assert_equal 10, Time.new(2005,2,22,15,15,0,"-08:00").change(:usec => 10).usec
-    assert_equal 10, Time.new(2005,2,22,15,15,0,"-08:00").change(:nsec => 10).nsec
-    assert_raise(ArgumentError) { Time.new(2005, 2, 22, 15, 15, 45, "-08:00").change(:usec => 1000000) }
-    assert_raise(ArgumentError) { Time.new(2005, 2, 22, 15, 15, 45, "-08:00").change(:nsec => 1000000000) }
+    assert_equal Time.new(2006, 2, 22, 15, 15, 10, "-08:00"), Time.new(2005, 2, 22, 15, 15, 10, "-08:00").change(year: 2006)
+    assert_equal Time.new(2005, 6, 22, 15, 15, 10, "-08:00"), Time.new(2005, 2, 22, 15, 15, 10, "-08:00").change(month: 6)
+    assert_equal Time.new(2012, 9, 22, 15, 15, 10, "-08:00"), Time.new(2005, 2, 22, 15, 15, 10, "-08:00").change(year: 2012, month: 9)
+    assert_equal Time.new(2005, 2, 22, 16, 0, 0, "-08:00"),   Time.new(2005, 2, 22, 15, 15, 10, "-08:00").change(hour: 16)
+    assert_equal Time.new(2005, 2, 22, 16, 45, 0, "-08:00"),  Time.new(2005, 2, 22, 15, 15, 10, "-08:00").change(hour: 16, min: 45)
+    assert_equal Time.new(2005, 2, 22, 15, 45, 0, "-08:00"),  Time.new(2005, 2, 22, 15, 15, 10, "-08:00").change(min: 45)
+    assert_equal Time.new(2005, 2, 22, 15, 15, 10, "-08:00"),  Time.new(2005, 2, 22, 15, 15, 0, "-08:00").change(sec: 10)
+    assert_equal 10, Time.new(2005, 2, 22, 15, 15, 0, "-08:00").change(usec: 10).usec
+    assert_equal 10, Time.new(2005, 2, 22, 15, 15, 0, "-08:00").change(nsec: 10).nsec
+    assert_raise(ArgumentError) { Time.new(2005, 2, 22, 15, 15, 45, "-08:00").change(usec: 1000000) }
+    assert_raise(ArgumentError) { Time.new(2005, 2, 22, 15, 15, 45, "-08:00").change(nsec: 1000000000) }
+  end
+
+  def test_change_offset
+    assert_equal Time.new(2006, 2, 22, 15, 15, 10, "-08:00"), Time.new(2006, 2, 22, 15, 15, 10, "+01:00").change(offset: "-08:00")
+    assert_equal Time.new(2006, 2, 22, 15, 15, 10, -28800), Time.new(2006, 2, 22, 15, 15, 10, 3600).change(offset: -28800)
+    assert_raise(ArgumentError) { Time.new(2005, 2, 22, 15, 15, 45, "+01:00").change(usec: 1000000, offset: "-08:00") }
+    assert_raise(ArgumentError) { Time.new(2005, 2, 22, 15, 15, 45, "+01:00").change(nsec: 1000000000, offset: -28800) }
   end
 
   def test_advance
-    assert_equal Time.local(2006,2,28,15,15,10), Time.local(2005,2,28,15,15,10).advance(:years => 1)
-    assert_equal Time.local(2005,6,28,15,15,10), Time.local(2005,2,28,15,15,10).advance(:months => 4)
-    assert_equal Time.local(2005,3,21,15,15,10), Time.local(2005,2,28,15,15,10).advance(:weeks => 3)
-    assert_equal Time.local(2005,3,25,3,15,10), Time.local(2005,2,28,15,15,10).advance(:weeks => 3.5)
-    assert_in_delta Time.local(2005,3,26,12,51,10), Time.local(2005,2,28,15,15,10).advance(:weeks => 3.7), 1
-    assert_equal Time.local(2005,3,5,15,15,10), Time.local(2005,2,28,15,15,10).advance(:days => 5)
-    assert_equal Time.local(2005,3,6,3,15,10), Time.local(2005,2,28,15,15,10).advance(:days => 5.5)
-    assert_in_delta Time.local(2005,3,6,8,3,10), Time.local(2005,2,28,15,15,10).advance(:days => 5.7), 1
-    assert_equal Time.local(2012,9,28,15,15,10), Time.local(2005,2,28,15,15,10).advance(:years => 7, :months => 7)
-    assert_equal Time.local(2013,10,3,15,15,10), Time.local(2005,2,28,15,15,10).advance(:years => 7, :months => 19, :days => 5)
-    assert_equal Time.local(2013,10,17,15,15,10), Time.local(2005,2,28,15,15,10).advance(:years => 7, :months => 19, :weeks => 2, :days => 5)
-    assert_equal Time.local(2001,12,27,15,15,10), Time.local(2005,2,28,15,15,10).advance(:years => -3, :months => -2, :days => -1)
-    assert_equal Time.local(2005,2,28,15,15,10), Time.local(2004,2,29,15,15,10).advance(:years => 1) #leap day plus one year
-    assert_equal Time.local(2005,2,28,20,15,10), Time.local(2005,2,28,15,15,10).advance(:hours => 5)
-    assert_equal Time.local(2005,2,28,15,22,10), Time.local(2005,2,28,15,15,10).advance(:minutes => 7)
-    assert_equal Time.local(2005,2,28,15,15,19), Time.local(2005,2,28,15,15,10).advance(:seconds => 9)
-    assert_equal Time.local(2005,2,28,20,22,19), Time.local(2005,2,28,15,15,10).advance(:hours => 5, :minutes => 7, :seconds => 9)
-    assert_equal Time.local(2005,2,28,10,8,1), Time.local(2005,2,28,15,15,10).advance(:hours => -5, :minutes => -7, :seconds => -9)
-    assert_equal Time.local(2013,10,17,20,22,19), Time.local(2005,2,28,15,15,10).advance(:years => 7, :months => 19, :weeks => 2, :days => 5, :hours => 5, :minutes => 7, :seconds => 9)
+    assert_equal Time.local(2006, 2, 28, 15, 15, 10), Time.local(2005, 2, 28, 15, 15, 10).advance(years: 1)
+    assert_equal Time.local(2005, 6, 28, 15, 15, 10), Time.local(2005, 2, 28, 15, 15, 10).advance(months: 4)
+    assert_equal Time.local(2005, 3, 21, 15, 15, 10), Time.local(2005, 2, 28, 15, 15, 10).advance(weeks: 3)
+    assert_equal Time.local(2005, 3, 25, 3, 15, 10), Time.local(2005, 2, 28, 15, 15, 10).advance(weeks: 3.5)
+    assert_in_delta Time.local(2005, 3, 26, 12, 51, 10), Time.local(2005, 2, 28, 15, 15, 10).advance(weeks: 3.7), 1
+    assert_equal Time.local(2005, 3, 5, 15, 15, 10), Time.local(2005, 2, 28, 15, 15, 10).advance(days: 5)
+    assert_equal Time.local(2005, 3, 6, 3, 15, 10), Time.local(2005, 2, 28, 15, 15, 10).advance(days: 5.5)
+    assert_in_delta Time.local(2005, 3, 6, 8, 3, 10), Time.local(2005, 2, 28, 15, 15, 10).advance(days: 5.7), 1
+    assert_equal Time.local(2012, 9, 28, 15, 15, 10), Time.local(2005, 2, 28, 15, 15, 10).advance(years: 7, months: 7)
+    assert_equal Time.local(2013, 10, 3, 15, 15, 10), Time.local(2005, 2, 28, 15, 15, 10).advance(years: 7, months: 19, days: 5)
+    assert_equal Time.local(2013, 10, 17, 15, 15, 10), Time.local(2005, 2, 28, 15, 15, 10).advance(years: 7, months: 19, weeks: 2, days: 5)
+    assert_equal Time.local(2001, 12, 27, 15, 15, 10), Time.local(2005, 2, 28, 15, 15, 10).advance(years: -3, months: -2, days: -1)
+    assert_equal Time.local(2005, 2, 28, 15, 15, 10), Time.local(2004, 2, 29, 15, 15, 10).advance(years: 1) # leap day plus one year
+    assert_equal Time.local(2005, 2, 28, 20, 15, 10), Time.local(2005, 2, 28, 15, 15, 10).advance(hours: 5)
+    assert_equal Time.local(2005, 2, 28, 15, 22, 10), Time.local(2005, 2, 28, 15, 15, 10).advance(minutes: 7)
+    assert_equal Time.local(2005, 2, 28, 15, 15, 19), Time.local(2005, 2, 28, 15, 15, 10).advance(seconds: 9)
+    assert_equal Time.local(2005, 2, 28, 20, 22, 19), Time.local(2005, 2, 28, 15, 15, 10).advance(hours: 5, minutes: 7, seconds: 9)
+    assert_equal Time.local(2005, 2, 28, 10, 8, 1), Time.local(2005, 2, 28, 15, 15, 10).advance(hours: -5, minutes: -7, seconds: -9)
+    assert_equal Time.local(2013, 10, 17, 20, 22, 19), Time.local(2005, 2, 28, 15, 15, 10).advance(years: 7, months: 19, weeks: 2, days: 5, hours: 5, minutes: 7, seconds: 9)
   end
 
   def test_utc_advance
-    assert_equal Time.utc(2006,2,22,15,15,10), Time.utc(2005,2,22,15,15,10).advance(:years => 1)
-    assert_equal Time.utc(2005,6,22,15,15,10), Time.utc(2005,2,22,15,15,10).advance(:months => 4)
-    assert_equal Time.utc(2005,3,21,15,15,10), Time.utc(2005,2,28,15,15,10).advance(:weeks => 3)
-    assert_equal Time.utc(2005,3,25,3,15,10), Time.utc(2005,2,28,15,15,10).advance(:weeks => 3.5)
-    assert_in_delta Time.utc(2005,3,26,12,51,10), Time.utc(2005,2,28,15,15,10).advance(:weeks => 3.7), 1
-    assert_equal Time.utc(2005,3,5,15,15,10), Time.utc(2005,2,28,15,15,10).advance(:days => 5)
-    assert_equal Time.utc(2005,3,6,3,15,10), Time.utc(2005,2,28,15,15,10).advance(:days => 5.5)
-    assert_in_delta Time.utc(2005,3,6,8,3,10), Time.utc(2005,2,28,15,15,10).advance(:days => 5.7), 1
-    assert_equal Time.utc(2012,9,22,15,15,10), Time.utc(2005,2,22,15,15,10).advance(:years => 7, :months => 7)
-    assert_equal Time.utc(2013,10,3,15,15,10), Time.utc(2005,2,22,15,15,10).advance(:years => 7, :months => 19, :days => 11)
-    assert_equal Time.utc(2013,10,17,15,15,10), Time.utc(2005,2,28,15,15,10).advance(:years => 7, :months => 19, :weeks => 2, :days => 5)
-    assert_equal Time.utc(2001,12,27,15,15,10), Time.utc(2005,2,28,15,15,10).advance(:years => -3, :months => -2, :days => -1)
-    assert_equal Time.utc(2005,2,28,15,15,10), Time.utc(2004,2,29,15,15,10).advance(:years => 1) #leap day plus one year
-    assert_equal Time.utc(2005,2,28,20,15,10), Time.utc(2005,2,28,15,15,10).advance(:hours => 5)
-    assert_equal Time.utc(2005,2,28,15,22,10), Time.utc(2005,2,28,15,15,10).advance(:minutes => 7)
-    assert_equal Time.utc(2005,2,28,15,15,19), Time.utc(2005,2,28,15,15,10).advance(:seconds => 9)
-    assert_equal Time.utc(2005,2,28,20,22,19), Time.utc(2005,2,28,15,15,10).advance(:hours => 5, :minutes => 7, :seconds => 9)
-    assert_equal Time.utc(2005,2,28,10,8,1), Time.utc(2005,2,28,15,15,10).advance(:hours => -5, :minutes => -7, :seconds => -9)
-    assert_equal Time.utc(2013,10,17,20,22,19), Time.utc(2005,2,28,15,15,10).advance(:years => 7, :months => 19, :weeks => 2, :days => 5, :hours => 5, :minutes => 7, :seconds => 9)
+    assert_equal Time.utc(2006, 2, 22, 15, 15, 10), Time.utc(2005, 2, 22, 15, 15, 10).advance(years: 1)
+    assert_equal Time.utc(2005, 6, 22, 15, 15, 10), Time.utc(2005, 2, 22, 15, 15, 10).advance(months: 4)
+    assert_equal Time.utc(2005, 3, 21, 15, 15, 10), Time.utc(2005, 2, 28, 15, 15, 10).advance(weeks: 3)
+    assert_equal Time.utc(2005, 3, 25, 3, 15, 10), Time.utc(2005, 2, 28, 15, 15, 10).advance(weeks: 3.5)
+    assert_in_delta Time.utc(2005, 3, 26, 12, 51, 10), Time.utc(2005, 2, 28, 15, 15, 10).advance(weeks: 3.7), 1
+    assert_equal Time.utc(2005, 3, 5, 15, 15, 10), Time.utc(2005, 2, 28, 15, 15, 10).advance(days: 5)
+    assert_equal Time.utc(2005, 3, 6, 3, 15, 10), Time.utc(2005, 2, 28, 15, 15, 10).advance(days: 5.5)
+    assert_in_delta Time.utc(2005, 3, 6, 8, 3, 10), Time.utc(2005, 2, 28, 15, 15, 10).advance(days: 5.7), 1
+    assert_equal Time.utc(2012, 9, 22, 15, 15, 10), Time.utc(2005, 2, 22, 15, 15, 10).advance(years: 7, months: 7)
+    assert_equal Time.utc(2013, 10, 3, 15, 15, 10), Time.utc(2005, 2, 22, 15, 15, 10).advance(years: 7, months: 19, days: 11)
+    assert_equal Time.utc(2013, 10, 17, 15, 15, 10), Time.utc(2005, 2, 28, 15, 15, 10).advance(years: 7, months: 19, weeks: 2, days: 5)
+    assert_equal Time.utc(2001, 12, 27, 15, 15, 10), Time.utc(2005, 2, 28, 15, 15, 10).advance(years: -3, months: -2, days: -1)
+    assert_equal Time.utc(2005, 2, 28, 15, 15, 10), Time.utc(2004, 2, 29, 15, 15, 10).advance(years: 1) # leap day plus one year
+    assert_equal Time.utc(2005, 2, 28, 20, 15, 10), Time.utc(2005, 2, 28, 15, 15, 10).advance(hours: 5)
+    assert_equal Time.utc(2005, 2, 28, 15, 22, 10), Time.utc(2005, 2, 28, 15, 15, 10).advance(minutes: 7)
+    assert_equal Time.utc(2005, 2, 28, 15, 15, 19), Time.utc(2005, 2, 28, 15, 15, 10).advance(seconds: 9)
+    assert_equal Time.utc(2005, 2, 28, 20, 22, 19), Time.utc(2005, 2, 28, 15, 15, 10).advance(hours: 5, minutes: 7, seconds: 9)
+    assert_equal Time.utc(2005, 2, 28, 10, 8, 1), Time.utc(2005, 2, 28, 15, 15, 10).advance(hours: -5, minutes: -7, seconds: -9)
+    assert_equal Time.utc(2013, 10, 17, 20, 22, 19), Time.utc(2005, 2, 28, 15, 15, 10).advance(years: 7, months: 19, weeks: 2, days: 5, hours: 5, minutes: 7, seconds: 9)
   end
 
   def test_offset_advance
-    assert_equal Time.new(2006,2,22,15,15,10,'-08:00'), Time.new(2005,2,22,15,15,10,'-08:00').advance(:years => 1)
-    assert_equal Time.new(2005,6,22,15,15,10,'-08:00'), Time.new(2005,2,22,15,15,10,'-08:00').advance(:months => 4)
-    assert_equal Time.new(2005,3,21,15,15,10,'-08:00'), Time.new(2005,2,28,15,15,10,'-08:00').advance(:weeks => 3)
-    assert_equal Time.new(2005,3,25,3,15,10,'-08:00'), Time.new(2005,2,28,15,15,10,'-08:00').advance(:weeks => 3.5)
-    assert_in_delta Time.new(2005,3,26,12,51,10,'-08:00'), Time.new(2005,2,28,15,15,10,'-08:00').advance(:weeks => 3.7), 1
-    assert_equal Time.new(2005,3,5,15,15,10,'-08:00'), Time.new(2005,2,28,15,15,10,'-08:00').advance(:days => 5)
-    assert_equal Time.new(2005,3,6,3,15,10,'-08:00'), Time.new(2005,2,28,15,15,10,'-08:00').advance(:days => 5.5)
-    assert_in_delta Time.new(2005,3,6,8,3,10,'-08:00'), Time.new(2005,2,28,15,15,10,'-08:00').advance(:days => 5.7), 1
-    assert_equal Time.new(2012,9,22,15,15,10,'-08:00'), Time.new(2005,2,22,15,15,10,'-08:00').advance(:years => 7, :months => 7)
-    assert_equal Time.new(2013,10,3,15,15,10,'-08:00'), Time.new(2005,2,22,15,15,10,'-08:00').advance(:years => 7, :months => 19, :days => 11)
-    assert_equal Time.new(2013,10,17,15,15,10,'-08:00'), Time.new(2005,2,28,15,15,10,'-08:00').advance(:years => 7, :months => 19, :weeks => 2, :days => 5)
-    assert_equal Time.new(2001,12,27,15,15,10,'-08:00'), Time.new(2005,2,28,15,15,10,'-08:00').advance(:years => -3, :months => -2, :days => -1)
-    assert_equal Time.new(2005,2,28,15,15,10,'-08:00'), Time.new(2004,2,29,15,15,10,'-08:00').advance(:years => 1) #leap day plus one year
-    assert_equal Time.new(2005,2,28,20,15,10,'-08:00'), Time.new(2005,2,28,15,15,10,'-08:00').advance(:hours => 5)
-    assert_equal Time.new(2005,2,28,15,22,10,'-08:00'), Time.new(2005,2,28,15,15,10,'-08:00').advance(:minutes => 7)
-    assert_equal Time.new(2005,2,28,15,15,19,'-08:00'), Time.new(2005,2,28,15,15,10,'-08:00').advance(:seconds => 9)
-    assert_equal Time.new(2005,2,28,20,22,19,'-08:00'), Time.new(2005,2,28,15,15,10,'-08:00').advance(:hours => 5, :minutes => 7, :seconds => 9)
-    assert_equal Time.new(2005,2,28,10,8,1,'-08:00'), Time.new(2005,2,28,15,15,10,'-08:00').advance(:hours => -5, :minutes => -7, :seconds => -9)
-    assert_equal Time.new(2013,10,17,20,22,19,'-08:00'), Time.new(2005,2,28,15,15,10,'-08:00').advance(:years => 7, :months => 19, :weeks => 2, :days => 5, :hours => 5, :minutes => 7, :seconds => 9)
+    assert_equal Time.new(2006, 2, 22, 15, 15, 10, "-08:00"), Time.new(2005, 2, 22, 15, 15, 10, "-08:00").advance(years: 1)
+    assert_equal Time.new(2005, 6, 22, 15, 15, 10, "-08:00"), Time.new(2005, 2, 22, 15, 15, 10, "-08:00").advance(months: 4)
+    assert_equal Time.new(2005, 3, 21, 15, 15, 10, "-08:00"), Time.new(2005, 2, 28, 15, 15, 10, "-08:00").advance(weeks: 3)
+    assert_equal Time.new(2005, 3, 25, 3, 15, 10, "-08:00"), Time.new(2005, 2, 28, 15, 15, 10, "-08:00").advance(weeks: 3.5)
+    assert_in_delta Time.new(2005, 3, 26, 12, 51, 10, "-08:00"), Time.new(2005, 2, 28, 15, 15, 10, "-08:00").advance(weeks: 3.7), 1
+    assert_equal Time.new(2005, 3, 5, 15, 15, 10, "-08:00"), Time.new(2005, 2, 28, 15, 15, 10, "-08:00").advance(days: 5)
+    assert_equal Time.new(2005, 3, 6, 3, 15, 10, "-08:00"), Time.new(2005, 2, 28, 15, 15, 10, "-08:00").advance(days: 5.5)
+    assert_in_delta Time.new(2005, 3, 6, 8, 3, 10, "-08:00"), Time.new(2005, 2, 28, 15, 15, 10, "-08:00").advance(days: 5.7), 1
+    assert_equal Time.new(2012, 9, 22, 15, 15, 10, "-08:00"), Time.new(2005, 2, 22, 15, 15, 10, "-08:00").advance(years: 7, months: 7)
+    assert_equal Time.new(2013, 10, 3, 15, 15, 10, "-08:00"), Time.new(2005, 2, 22, 15, 15, 10, "-08:00").advance(years: 7, months: 19, days: 11)
+    assert_equal Time.new(2013, 10, 17, 15, 15, 10, "-08:00"), Time.new(2005, 2, 28, 15, 15, 10, "-08:00").advance(years: 7, months: 19, weeks: 2, days: 5)
+    assert_equal Time.new(2001, 12, 27, 15, 15, 10, "-08:00"), Time.new(2005, 2, 28, 15, 15, 10, "-08:00").advance(years: -3, months: -2, days: -1)
+    assert_equal Time.new(2005, 2, 28, 15, 15, 10, "-08:00"), Time.new(2004, 2, 29, 15, 15, 10, "-08:00").advance(years: 1) # leap day plus one year
+    assert_equal Time.new(2005, 2, 28, 20, 15, 10, "-08:00"), Time.new(2005, 2, 28, 15, 15, 10, "-08:00").advance(hours: 5)
+    assert_equal Time.new(2005, 2, 28, 15, 22, 10, "-08:00"), Time.new(2005, 2, 28, 15, 15, 10, "-08:00").advance(minutes: 7)
+    assert_equal Time.new(2005, 2, 28, 15, 15, 19, "-08:00"), Time.new(2005, 2, 28, 15, 15, 10, "-08:00").advance(seconds: 9)
+    assert_equal Time.new(2005, 2, 28, 20, 22, 19, "-08:00"), Time.new(2005, 2, 28, 15, 15, 10, "-08:00").advance(hours: 5, minutes: 7, seconds: 9)
+    assert_equal Time.new(2005, 2, 28, 10, 8, 1, "-08:00"), Time.new(2005, 2, 28, 15, 15, 10, "-08:00").advance(hours: -5, minutes: -7, seconds: -9)
+    assert_equal Time.new(2013, 10, 17, 20, 22, 19, "-08:00"), Time.new(2005, 2, 28, 15, 15, 10, "-08:00").advance(years: 7, months: 19, weeks: 2, days: 5, hours: 5, minutes: 7, seconds: 9)
   end
 
   def test_advance_with_nsec
     t = Time.at(0, Rational(108635108, 1000))
-    assert_equal t, t.advance(:months => 0)
+    assert_equal t, t.advance(months: 0)
   end
 
   def test_advance_gregorian_proleptic
-    assert_equal Time.local(1582,10,14,15,15,10), Time.local(1582,10,15,15,15,10).advance(:days => -1)
-    assert_equal Time.local(1582,10,15,15,15,10), Time.local(1582,10,14,15,15,10).advance(:days => 1)
-    assert_equal Time.local(1582,10,5,15,15,10), Time.local(1582,10,4,15,15,10).advance(:days => 1)
-    assert_equal Time.local(1582,10,4,15,15,10), Time.local(1582,10,5,15,15,10).advance(:days => -1)
+    assert_equal Time.local(1582, 10, 14, 15, 15, 10), Time.local(1582, 10, 15, 15, 15, 10).advance(days: -1)
+    assert_equal Time.local(1582, 10, 15, 15, 15, 10), Time.local(1582, 10, 14, 15, 15, 10).advance(days: 1)
+    assert_equal Time.local(1582, 10, 5, 15, 15, 10), Time.local(1582, 10, 4, 15, 15, 10).advance(days: 1)
+    assert_equal Time.local(1582, 10, 4, 15, 15, 10), Time.local(1582, 10, 5, 15, 15, 10).advance(days: -1)
   end
 
   def test_last_week
-    with_env_tz 'US/Eastern' do
-      assert_equal Time.local(2005,2,21), Time.local(2005,3,1,15,15,10).last_week
-      assert_equal Time.local(2005,2,22), Time.local(2005,3,1,15,15,10).last_week(:tuesday)
-      assert_equal Time.local(2005,2,25), Time.local(2005,3,1,15,15,10).last_week(:friday)
-      assert_equal Time.local(2006,10,30), Time.local(2006,11,6,0,0,0).last_week
-      assert_equal Time.local(2006,11,15), Time.local(2006,11,23,0,0,0).last_week(:wednesday)
+    with_env_tz "US/Eastern" do
+      assert_equal Time.local(2005, 2, 21), Time.local(2005, 3, 1, 15, 15, 10).last_week
+      assert_equal Time.local(2005, 2, 22), Time.local(2005, 3, 1, 15, 15, 10).last_week(:tuesday)
+      assert_equal Time.local(2005, 2, 25), Time.local(2005, 3, 1, 15, 15, 10).last_week(:friday)
+      assert_equal Time.local(2006, 10, 30), Time.local(2006, 11, 6, 0, 0, 0).last_week
+      assert_equal Time.local(2006, 11, 15), Time.local(2006, 11, 23, 0, 0, 0).last_week(:wednesday)
     end
   end
 
   def test_next_week_near_daylight_start
-    with_env_tz 'US/Eastern' do
-      assert_equal Time.local(2006,4,3), Time.local(2006,4,2,23,1,0).next_week, 'just crossed standard => daylight'
+    with_env_tz "US/Eastern" do
+      assert_equal Time.local(2006, 4, 3), Time.local(2006, 4, 2, 23, 1, 0).next_week, "just crossed standard => daylight"
     end
-    with_env_tz 'NZ' do
-      assert_equal Time.local(2006,10,2), Time.local(2006,10,1,23,1,0).next_week, 'just crossed standard => daylight'
+    with_env_tz "NZ" do
+      assert_equal Time.local(2006, 10, 2), Time.local(2006, 10, 1, 23, 1, 0).next_week, "just crossed standard => daylight"
     end
   end
 
   def test_next_week_near_daylight_end
-    with_env_tz 'US/Eastern' do
-      assert_equal Time.local(2006,10,30), Time.local(2006,10,29,23,1,0).next_week, 'just crossed daylight => standard'
+    with_env_tz "US/Eastern" do
+      assert_equal Time.local(2006, 10, 30), Time.local(2006, 10, 29, 23, 1, 0).next_week, "just crossed daylight => standard"
     end
-    with_env_tz 'NZ' do
-      assert_equal Time.local(2006,3,20), Time.local(2006,3,19,23,1,0).next_week, 'just crossed daylight => standard'
+    with_env_tz "NZ" do
+      assert_equal Time.local(2006, 3, 20), Time.local(2006, 3, 19, 23, 1, 0).next_week, "just crossed daylight => standard"
     end
   end
 
@@ -564,28 +569,33 @@ class TimeExtCalculationsTest < ActiveSupport::TestCase
   end
 
   def test_custom_date_format
-    Time::DATE_FORMATS[:custom] = '%Y%m%d%H%M%S'
-    assert_equal '20050221143000', Time.local(2005, 2, 21, 14, 30, 0).to_s(:custom)
+    Time::DATE_FORMATS[:custom] = "%Y%m%d%H%M%S"
+    assert_equal "20050221143000", Time.local(2005, 2, 21, 14, 30, 0).to_s(:custom)
     Time::DATE_FORMATS.delete(:custom)
   end
 
+  def test_rfc3339_with_fractional_seconds
+    time = Time.new(1999, 12, 31, 19, 0, Rational(1, 8), -18000)
+    assert_equal "1999-12-31T19:00:00.125-05:00", time.rfc3339(3)
+  end
+
   def test_to_date
     assert_equal Date.new(2005, 2, 21), Time.local(2005, 2, 21, 17, 44, 30).to_date
   end
 
   def test_to_datetime
     assert_equal Time.utc(2005, 2, 21, 17, 44, 30).to_datetime, DateTime.civil(2005, 2, 21, 17, 44, 30, 0)
-    with_env_tz 'US/Eastern' do
+    with_env_tz "US/Eastern" do
       assert_equal Time.local(2005, 2, 21, 17, 44, 30).to_datetime, DateTime.civil(2005, 2, 21, 17, 44, 30, Rational(Time.local(2005, 2, 21, 17, 44, 30).utc_offset, 86400))
     end
-    with_env_tz 'NZ' do
+    with_env_tz "NZ" do
       assert_equal Time.local(2005, 2, 21, 17, 44, 30).to_datetime, DateTime.civil(2005, 2, 21, 17, 44, 30, Rational(Time.local(2005, 2, 21, 17, 44, 30).utc_offset, 86400))
     end
     assert_equal ::Date::ITALY, Time.utc(2005, 2, 21, 17, 44, 30).to_datetime.start # use Ruby's default start value
   end
 
   def test_to_time
-    with_env_tz 'US/Eastern' do
+    with_env_tz "US/Eastern" do
       assert_equal Time, Time.local(2005, 2, 21, 17, 44, 30).to_time.class
       assert_equal Time.local(2005, 2, 21, 17, 44, 30), Time.local(2005, 2, 21, 17, 44, 30).to_time
       assert_equal Time.local(2005, 2, 21, 17, 44, 30).utc_offset, Time.local(2005, 2, 21, 17, 44, 30).to_time.utc_offset
@@ -650,82 +660,78 @@ class TimeExtCalculationsTest < ActiveSupport::TestCase
     end
   end
 
-  def test_last_month_on_31st
-    assert_equal Time.local(2004, 2, 29), Time.local(2004, 3, 31).last_month
-  end
-
   def test_xmlschema_is_available
     assert_nothing_raised { Time.now.xmlschema }
   end
 
   def test_today_with_time_local
     Date.stub(:current, Date.new(2000, 1, 1)) do
-      assert_equal false, Time.local(1999,12,31,23,59,59).today?
-      assert_equal true,  Time.local(2000,1,1,0).today?
-      assert_equal true,  Time.local(2000,1,1,23,59,59).today?
-      assert_equal false, Time.local(2000,1,2,0).today?
+      assert_equal false, Time.local(1999, 12, 31, 23, 59, 59).today?
+      assert_equal true,  Time.local(2000, 1, 1, 0).today?
+      assert_equal true,  Time.local(2000, 1, 1, 23, 59, 59).today?
+      assert_equal false, Time.local(2000, 1, 2, 0).today?
     end
   end
 
   def test_today_with_time_utc
     Date.stub(:current, Date.new(2000, 1, 1)) do
-      assert_equal false, Time.utc(1999,12,31,23,59,59).today?
-      assert_equal true,  Time.utc(2000,1,1,0).today?
-      assert_equal true,  Time.utc(2000,1,1,23,59,59).today?
-      assert_equal false, Time.utc(2000,1,2,0).today?
+      assert_equal false, Time.utc(1999, 12, 31, 23, 59, 59).today?
+      assert_equal true,  Time.utc(2000, 1, 1, 0).today?
+      assert_equal true,  Time.utc(2000, 1, 1, 23, 59, 59).today?
+      assert_equal false, Time.utc(2000, 1, 2, 0).today?
     end
   end
 
   def test_past_with_time_current_as_time_local
-    with_env_tz 'US/Eastern' do
-      Time.stub(:current, Time.local(2005,2,10,15,30,45)) do
-        assert_equal true,  Time.local(2005,2,10,15,30,44).past?
-        assert_equal false,  Time.local(2005,2,10,15,30,45).past?
-        assert_equal false,  Time.local(2005,2,10,15,30,46).past?
-        assert_equal true,  Time.utc(2005,2,10,20,30,44).past?
-        assert_equal false,  Time.utc(2005,2,10,20,30,45).past?
-        assert_equal false,  Time.utc(2005,2,10,20,30,46).past?
+    with_env_tz "US/Eastern" do
+      Time.stub(:current, Time.local(2005, 2, 10, 15, 30, 45)) do
+        assert_equal true,  Time.local(2005, 2, 10, 15, 30, 44).past?
+        assert_equal false,  Time.local(2005, 2, 10, 15, 30, 45).past?
+        assert_equal false,  Time.local(2005, 2, 10, 15, 30, 46).past?
+        assert_equal true,  Time.utc(2005, 2, 10, 20, 30, 44).past?
+        assert_equal false,  Time.utc(2005, 2, 10, 20, 30, 45).past?
+        assert_equal false,  Time.utc(2005, 2, 10, 20, 30, 46).past?
       end
     end
   end
 
   def test_past_with_time_current_as_time_with_zone
-    with_env_tz 'US/Eastern' do
-      twz = Time.utc(2005,2,10,15,30,45).in_time_zone('Central Time (US & Canada)')
+    with_env_tz "US/Eastern" do
+      twz = Time.utc(2005, 2, 10, 15, 30, 45).in_time_zone("Central Time (US & Canada)")
       Time.stub(:current, twz) do
-        assert_equal true,  Time.local(2005,2,10,10,30,44).past?
-        assert_equal false,  Time.local(2005,2,10,10,30,45).past?
-        assert_equal false,  Time.local(2005,2,10,10,30,46).past?
-        assert_equal true,  Time.utc(2005,2,10,15,30,44).past?
-        assert_equal false,  Time.utc(2005,2,10,15,30,45).past?
-        assert_equal false,  Time.utc(2005,2,10,15,30,46).past?
+        assert_equal true,  Time.local(2005, 2, 10, 10, 30, 44).past?
+        assert_equal false,  Time.local(2005, 2, 10, 10, 30, 45).past?
+        assert_equal false,  Time.local(2005, 2, 10, 10, 30, 46).past?
+        assert_equal true,  Time.utc(2005, 2, 10, 15, 30, 44).past?
+        assert_equal false,  Time.utc(2005, 2, 10, 15, 30, 45).past?
+        assert_equal false,  Time.utc(2005, 2, 10, 15, 30, 46).past?
       end
     end
   end
 
   def test_future_with_time_current_as_time_local
-    with_env_tz 'US/Eastern' do
-      Time.stub(:current, Time.local(2005,2,10,15,30,45)) do
-        assert_equal false,  Time.local(2005,2,10,15,30,44).future?
-        assert_equal false,  Time.local(2005,2,10,15,30,45).future?
-        assert_equal true,  Time.local(2005,2,10,15,30,46).future?
-        assert_equal false,  Time.utc(2005,2,10,20,30,44).future?
-        assert_equal false,  Time.utc(2005,2,10,20,30,45).future?
-        assert_equal true,  Time.utc(2005,2,10,20,30,46).future?
+    with_env_tz "US/Eastern" do
+      Time.stub(:current, Time.local(2005, 2, 10, 15, 30, 45)) do
+        assert_equal false,  Time.local(2005, 2, 10, 15, 30, 44).future?
+        assert_equal false,  Time.local(2005, 2, 10, 15, 30, 45).future?
+        assert_equal true,  Time.local(2005, 2, 10, 15, 30, 46).future?
+        assert_equal false,  Time.utc(2005, 2, 10, 20, 30, 44).future?
+        assert_equal false,  Time.utc(2005, 2, 10, 20, 30, 45).future?
+        assert_equal true,  Time.utc(2005, 2, 10, 20, 30, 46).future?
       end
     end
   end
 
   def test_future_with_time_current_as_time_with_zone
-    with_env_tz 'US/Eastern' do
-      twz = Time.utc(2005,2,10,15,30,45).in_time_zone('Central Time (US & Canada)')
+    with_env_tz "US/Eastern" do
+      twz = Time.utc(2005, 2, 10, 15, 30, 45).in_time_zone("Central Time (US & Canada)")
       Time.stub(:current, twz) do
-        assert_equal false,  Time.local(2005,2,10,10,30,44).future?
-        assert_equal false,  Time.local(2005,2,10,10,30,45).future?
-        assert_equal true,  Time.local(2005,2,10,10,30,46).future?
-        assert_equal false,  Time.utc(2005,2,10,15,30,44).future?
-        assert_equal false,  Time.utc(2005,2,10,15,30,45).future?
-        assert_equal true,  Time.utc(2005,2,10,15,30,46).future?
+        assert_equal false,  Time.local(2005, 2, 10, 10, 30, 44).future?
+        assert_equal false,  Time.local(2005, 2, 10, 10, 30, 45).future?
+        assert_equal true,  Time.local(2005, 2, 10, 10, 30, 46).future?
+        assert_equal false,  Time.utc(2005, 2, 10, 15, 30, 44).future?
+        assert_equal false,  Time.utc(2005, 2, 10, 15, 30, 45).future?
+        assert_equal true,  Time.utc(2005, 2, 10, 15, 30, 46).future?
       end
     end
   end
@@ -735,17 +741,17 @@ class TimeExtCalculationsTest < ActiveSupport::TestCase
   end
 
   def test_formatted_offset_with_utc
-    assert_equal '+00:00', Time.utc(2000).formatted_offset
-    assert_equal '+0000', Time.utc(2000).formatted_offset(false)
-    assert_equal 'UTC', Time.utc(2000).formatted_offset(true, 'UTC')
+    assert_equal "+00:00", Time.utc(2000).formatted_offset
+    assert_equal "+0000", Time.utc(2000).formatted_offset(false)
+    assert_equal "UTC", Time.utc(2000).formatted_offset(true, "UTC")
   end
 
   def test_formatted_offset_with_local
-    with_env_tz 'US/Eastern' do
-      assert_equal '-05:00', Time.local(2000).formatted_offset
-      assert_equal '-0500', Time.local(2000).formatted_offset(false)
-      assert_equal '-04:00', Time.local(2000, 7).formatted_offset
-      assert_equal '-0400', Time.local(2000, 7).formatted_offset(false)
+    with_env_tz "US/Eastern" do
+      assert_equal "-05:00", Time.local(2000).formatted_offset
+      assert_equal "-0500", Time.local(2000).formatted_offset(false)
+      assert_equal "-04:00", Time.local(2000, 7).formatted_offset
+      assert_equal "-0400", Time.local(2000, 7).formatted_offset(false)
     end
   end
 
@@ -762,16 +768,16 @@ class TimeExtCalculationsTest < ActiveSupport::TestCase
   end
 
   def test_compare_with_time_with_zone
-    assert_equal  1, Time.utc(2000) <=> ActiveSupport::TimeWithZone.new( Time.utc(1999, 12, 31, 23, 59, 59), ActiveSupport::TimeZone['UTC'] )
-    assert_equal  0, Time.utc(2000) <=> ActiveSupport::TimeWithZone.new( Time.utc(2000, 1, 1, 0, 0, 0), ActiveSupport::TimeZone['UTC'] )
-    assert_equal(-1, Time.utc(2000) <=> ActiveSupport::TimeWithZone.new( Time.utc(2000, 1, 1, 0, 0, 1), ActiveSupport::TimeZone['UTC'] ))
+    assert_equal  1, Time.utc(2000) <=> ActiveSupport::TimeWithZone.new(Time.utc(1999, 12, 31, 23, 59, 59), ActiveSupport::TimeZone["UTC"])
+    assert_equal  0, Time.utc(2000) <=> ActiveSupport::TimeWithZone.new(Time.utc(2000, 1, 1, 0, 0, 0), ActiveSupport::TimeZone["UTC"])
+    assert_equal(-1, Time.utc(2000) <=> ActiveSupport::TimeWithZone.new(Time.utc(2000, 1, 1, 0, 0, 1), ActiveSupport::TimeZone["UTC"]))
   end
 
   def test_compare_with_string
     assert_equal   1, Time.utc(2000) <=> Time.utc(1999, 12, 31, 23, 59, 59, 999).to_s
     assert_equal   0, Time.utc(2000) <=> Time.utc(2000, 1, 1, 0, 0, 0).to_s
-    assert_equal( -1, Time.utc(2000) <=> Time.utc(2000, 1, 1, 0, 0, 1, 0).to_s)
-    assert_equal nil, Time.utc(2000) <=> 'Invalid as Time'
+    assert_equal(-1, Time.utc(2000) <=> Time.utc(2000, 1, 1, 0, 0, 1, 0).to_s)
+    assert_nil Time.utc(2000) <=> "Invalid as Time"
   end
 
   def test_at_with_datetime
@@ -786,42 +792,42 @@ class TimeExtCalculationsTest < ActiveSupport::TestCase
   end
 
   def test_at_with_datetime_returns_local_time
-    with_env_tz 'US/Eastern' do
-      dt = DateTime.civil(2000, 1, 1, 0, 0, 0, '+0')
+    with_env_tz "US/Eastern" do
+      dt = DateTime.civil(2000, 1, 1, 0, 0, 0, "+0")
       assert_equal Time.local(1999, 12, 31, 19, 0, 0), Time.at(dt)
-      assert_equal 'EST', Time.at(dt).zone
+      assert_equal "EST", Time.at(dt).zone
       assert_equal(-18000, Time.at(dt).utc_offset)
 
       # Daylight savings
-      dt = DateTime.civil(2000, 7, 1, 1, 0, 0, '+1')
+      dt = DateTime.civil(2000, 7, 1, 1, 0, 0, "+1")
       assert_equal Time.local(2000, 6, 30, 20, 0, 0), Time.at(dt)
-      assert_equal 'EDT', Time.at(dt).zone
+      assert_equal "EDT", Time.at(dt).zone
       assert_equal(-14400, Time.at(dt).utc_offset)
     end
   end
 
   def test_at_with_time_with_zone
-    assert_equal Time.utc(2000, 1, 1, 0, 0, 0), Time.at(ActiveSupport::TimeWithZone.new(Time.utc(2000, 1, 1, 0, 0, 0), ActiveSupport::TimeZone['UTC']))
+    assert_equal Time.utc(2000, 1, 1, 0, 0, 0), Time.at(ActiveSupport::TimeWithZone.new(Time.utc(2000, 1, 1, 0, 0, 0), ActiveSupport::TimeZone["UTC"]))
 
     # Only test this if the underlying Time.at raises a TypeError
     begin
       Time.at_without_coercion(Time.now, 0)
     rescue TypeError
-      assert_raise(TypeError) { assert_equal(Time.utc(2000, 1, 1, 0, 0, 0), Time.at(ActiveSupport::TimeWithZone.new(Time.utc(2000, 1, 1, 0, 0, 0), ActiveSupport::TimeZone['UTC']), 0)) }
+      assert_raise(TypeError) { assert_equal(Time.utc(2000, 1, 1, 0, 0, 0), Time.at(ActiveSupport::TimeWithZone.new(Time.utc(2000, 1, 1, 0, 0, 0), ActiveSupport::TimeZone["UTC"]), 0)) }
     end
   end
 
   def test_at_with_time_with_zone_returns_local_time
-    with_env_tz 'US/Eastern' do
-      twz = ActiveSupport::TimeWithZone.new(Time.utc(2000, 1, 1, 0, 0, 0), ActiveSupport::TimeZone['London'])
+    with_env_tz "US/Eastern" do
+      twz = ActiveSupport::TimeWithZone.new(Time.utc(2000, 1, 1, 0, 0, 0), ActiveSupport::TimeZone["London"])
       assert_equal Time.local(1999, 12, 31, 19, 0, 0), Time.at(twz)
-      assert_equal 'EST', Time.at(twz).zone
+      assert_equal "EST", Time.at(twz).zone
       assert_equal(-18000, Time.at(twz).utc_offset)
 
       # Daylight savings
-      twz = ActiveSupport::TimeWithZone.new(Time.utc(2000, 7, 1, 0, 0, 0), ActiveSupport::TimeZone['London'])
+      twz = ActiveSupport::TimeWithZone.new(Time.utc(2000, 7, 1, 0, 0, 0), ActiveSupport::TimeZone["London"])
       assert_equal Time.local(2000, 6, 30, 20, 0, 0), Time.at(twz)
-      assert_equal 'EDT', Time.at(twz).zone
+      assert_equal "EDT", Time.at(twz).zone
       assert_equal(-14400, Time.at(twz).utc_offset)
     end
   end
@@ -831,33 +837,33 @@ class TimeExtCalculationsTest < ActiveSupport::TestCase
   end
 
   def test_at_with_utc_time
-    with_env_tz 'US/Eastern' do
+    with_env_tz "US/Eastern" do
       assert_equal Time.utc(2000), Time.at(Time.utc(2000))
-      assert_equal 'UTC', Time.at(Time.utc(2000)).zone
+      assert_equal "UTC", Time.at(Time.utc(2000)).zone
       assert_equal(0, Time.at(Time.utc(2000)).utc_offset)
     end
   end
 
   def test_at_with_local_time
-    with_env_tz 'US/Eastern' do
+    with_env_tz "US/Eastern" do
       assert_equal Time.local(2000), Time.at(Time.local(2000))
-      assert_equal 'EST', Time.at(Time.local(2000)).zone
+      assert_equal "EST", Time.at(Time.local(2000)).zone
       assert_equal(-18000, Time.at(Time.local(2000)).utc_offset)
 
       assert_equal Time.local(2000, 7, 1), Time.at(Time.local(2000, 7, 1))
-      assert_equal 'EDT', Time.at(Time.local(2000, 7, 1)).zone
+      assert_equal "EDT", Time.at(Time.local(2000, 7, 1)).zone
       assert_equal(-14400, Time.at(Time.local(2000, 7, 1)).utc_offset)
     end
   end
 
   def test_eql?
-    assert_equal true, Time.utc(2000).eql?( ActiveSupport::TimeWithZone.new(Time.utc(2000), ActiveSupport::TimeZone['UTC']) )
-    assert_equal true, Time.utc(2000).eql?( ActiveSupport::TimeWithZone.new(Time.utc(2000), ActiveSupport::TimeZone["Hawaii"]) )
-    assert_equal false,Time.utc(2000, 1, 1, 0, 0, 1).eql?( ActiveSupport::TimeWithZone.new(Time.utc(2000), ActiveSupport::TimeZone['UTC']) )
+    assert_equal true, Time.utc(2000).eql?(ActiveSupport::TimeWithZone.new(Time.utc(2000), ActiveSupport::TimeZone["UTC"]))
+    assert_equal true, Time.utc(2000).eql?(ActiveSupport::TimeWithZone.new(Time.utc(2000), ActiveSupport::TimeZone["Hawaii"]))
+    assert_equal false, Time.utc(2000, 1, 1, 0, 0, 1).eql?(ActiveSupport::TimeWithZone.new(Time.utc(2000), ActiveSupport::TimeZone["UTC"]))
   end
 
   def test_minus_with_time_with_zone
-    assert_equal  86_400.0, Time.utc(2000, 1, 2) - ActiveSupport::TimeWithZone.new( Time.utc(2000, 1, 1), ActiveSupport::TimeZone['UTC'] )
+    assert_equal  86_400.0, Time.utc(2000, 1, 2) - ActiveSupport::TimeWithZone.new(Time.utc(2000, 1, 1), ActiveSupport::TimeZone["UTC"])
   end
 
   def test_minus_with_datetime
@@ -865,7 +871,7 @@ class TimeExtCalculationsTest < ActiveSupport::TestCase
   end
 
   def test_time_created_with_local_constructor_cannot_represent_times_during_hour_skipped_by_dst
-    with_env_tz 'US/Eastern' do
+    with_env_tz "US/Eastern" do
       # On Apr 2 2006 at 2:00AM in US, clocks were moved forward to 3:00AM.
       # Therefore, 2AM EST doesn't exist for this date; Time.local fails over to 3:00AM EDT
       assert_equal Time.local(2006, 4, 2, 3), Time.local(2006, 4, 2, 2)
@@ -875,40 +881,71 @@ class TimeExtCalculationsTest < ActiveSupport::TestCase
 
   def test_case_equality
     assert Time === Time.utc(2000)
-    assert Time === ActiveSupport::TimeWithZone.new(Time.utc(2000), ActiveSupport::TimeZone['UTC'])
+    assert Time === ActiveSupport::TimeWithZone.new(Time.utc(2000), ActiveSupport::TimeZone["UTC"])
     assert Time === Class.new(Time).utc(2000)
     assert_equal false, Time === DateTime.civil(2000)
     assert_equal false, Class.new(Time) === Time.utc(2000)
-    assert_equal false, Class.new(Time) === ActiveSupport::TimeWithZone.new(Time.utc(2000), ActiveSupport::TimeZone['UTC'])
+    assert_equal false, Class.new(Time) === ActiveSupport::TimeWithZone.new(Time.utc(2000), ActiveSupport::TimeZone["UTC"])
   end
 
   def test_all_day
-    assert_equal Time.local(2011,6,7,0,0,0)..Time.local(2011,6,7,23,59,59,Rational(999999999, 1000)), Time.local(2011,6,7,10,10,10).all_day
+    assert_equal Time.local(2011, 6, 7, 0, 0, 0)..Time.local(2011, 6, 7, 23, 59, 59, Rational(999999999, 1000)), Time.local(2011, 6, 7, 10, 10, 10).all_day
   end
 
   def test_all_day_with_timezone
-    beginning_of_day = ActiveSupport::TimeWithZone.new(nil, ActiveSupport::TimeZone["Hawaii"], Time.local(2011,6,7,0,0,0))
-    end_of_day = ActiveSupport::TimeWithZone.new(nil, ActiveSupport::TimeZone["Hawaii"], Time.local(2011,6,7,23,59,59,Rational(999999999, 1000)))
+    beginning_of_day = ActiveSupport::TimeWithZone.new(nil, ActiveSupport::TimeZone["Hawaii"], Time.local(2011, 6, 7, 0, 0, 0))
+    end_of_day = ActiveSupport::TimeWithZone.new(nil, ActiveSupport::TimeZone["Hawaii"], Time.local(2011, 6, 7, 23, 59, 59, Rational(999999999, 1000)))
 
-    assert_equal beginning_of_day, ActiveSupport::TimeWithZone.new(Time.local(2011,6,7,10,10,10), ActiveSupport::TimeZone["Hawaii"]).all_day.begin
-    assert_equal end_of_day, ActiveSupport::TimeWithZone.new(Time.local(2011,6,7,10,10,10), ActiveSupport::TimeZone["Hawaii"]).all_day.end
+    assert_equal beginning_of_day, ActiveSupport::TimeWithZone.new(Time.local(2011, 6, 7, 10, 10, 10), ActiveSupport::TimeZone["Hawaii"]).all_day.begin
+    assert_equal end_of_day, ActiveSupport::TimeWithZone.new(Time.local(2011, 6, 7, 10, 10, 10), ActiveSupport::TimeZone["Hawaii"]).all_day.end
   end
 
   def test_all_week
-    assert_equal Time.local(2011,6,6,0,0,0)..Time.local(2011,6,12,23,59,59,Rational(999999999, 1000)), Time.local(2011,6,7,10,10,10).all_week
-    assert_equal Time.local(2011,6,5,0,0,0)..Time.local(2011,6,11,23,59,59,Rational(999999999, 1000)), Time.local(2011,6,7,10,10,10).all_week(:sunday)
+    assert_equal Time.local(2011, 6, 6, 0, 0, 0)..Time.local(2011, 6, 12, 23, 59, 59, Rational(999999999, 1000)), Time.local(2011, 6, 7, 10, 10, 10).all_week
+    assert_equal Time.local(2011, 6, 5, 0, 0, 0)..Time.local(2011, 6, 11, 23, 59, 59, Rational(999999999, 1000)), Time.local(2011, 6, 7, 10, 10, 10).all_week(:sunday)
   end
 
   def test_all_month
-    assert_equal Time.local(2011,6,1,0,0,0)..Time.local(2011,6,30,23,59,59,Rational(999999999, 1000)), Time.local(2011,6,7,10,10,10).all_month
+    assert_equal Time.local(2011, 6, 1, 0, 0, 0)..Time.local(2011, 6, 30, 23, 59, 59, Rational(999999999, 1000)), Time.local(2011, 6, 7, 10, 10, 10).all_month
   end
 
   def test_all_quarter
-    assert_equal Time.local(2011,4,1,0,0,0)..Time.local(2011,6,30,23,59,59,Rational(999999999, 1000)), Time.local(2011,6,7,10,10,10).all_quarter
+    assert_equal Time.local(2011, 4, 1, 0, 0, 0)..Time.local(2011, 6, 30, 23, 59, 59, Rational(999999999, 1000)), Time.local(2011, 6, 7, 10, 10, 10).all_quarter
   end
 
   def test_all_year
-    assert_equal Time.local(2011,1,1,0,0,0)..Time.local(2011,12,31,23,59,59,Rational(999999999, 1000)), Time.local(2011,6,7,10,10,10).all_year
+    assert_equal Time.local(2011, 1, 1, 0, 0, 0)..Time.local(2011, 12, 31, 23, 59, 59, Rational(999999999, 1000)), Time.local(2011, 6, 7, 10, 10, 10).all_year
+  end
+
+  def test_rfc3339_parse
+    time = Time.rfc3339("1999-12-31T19:00:00.125-05:00")
+
+    assert_equal 1999, time.year
+    assert_equal 12, time.month
+    assert_equal 31, time.day
+    assert_equal 19, time.hour
+    assert_equal 0, time.min
+    assert_equal 0, time.sec
+    assert_equal 125000, time.usec
+    assert_equal(-18000, time.utc_offset)
+
+    exception = assert_raises(ArgumentError) do
+      Time.rfc3339("1999-12-31")
+    end
+
+    assert_equal "invalid date", exception.message
+
+    exception = assert_raises(ArgumentError) do
+      Time.rfc3339("1999-12-31T19:00:00")
+    end
+
+    assert_equal "invalid date", exception.message
+
+    exception = assert_raises(ArgumentError) do
+      Time.rfc3339("foobar")
+    end
+
+    assert_equal "invalid date", exception.message
   end
 end
 
@@ -942,7 +979,7 @@ class TimeExtMarshalingTest < ActiveSupport::TestCase
   end
 
   def test_marshalling_preserves_fractional_seconds
-    t = Time.parse('00:00:00.500')
+    t = Time.parse("00:00:00.500")
     unmarshaled = Marshal.load(Marshal.dump(t))
     assert_equal t.to_f, unmarshaled.to_f
     assert_equal t, unmarshaled
diff --git a/activesupport/test/core_ext/time_with_zone_test.rb b/activesupport/test/core_ext/time_with_zone_test.rb
index d90714acdb..b25747eadb 100644
--- a/activesupport/test/core_ext/time_with_zone_test.rb
+++ b/activesupport/test/core_ext/time_with_zone_test.rb
@@ -1,15 +1,17 @@
-require 'abstract_unit'
-require 'active_support/time'
-require 'time_zone_test_helpers'
-require 'active_support/core_ext/string/strip'
-require 'yaml'
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "active_support/time"
+require "time_zone_test_helpers"
+require "active_support/core_ext/string/strip"
+require "yaml"
 
 class TimeWithZoneTest < ActiveSupport::TestCase
   include TimeZoneTestHelpers
 
   def setup
     @utc = Time.utc(2000, 1, 1, 0)
-    @time_zone = ActiveSupport::TimeZone['Eastern Time (US & Canada)']
+    @time_zone = ActiveSupport::TimeZone["Eastern Time (US & Canada)"]
     @twz = ActiveSupport::TimeWithZone.new(@utc, @time_zone)
     @dt_twz = ActiveSupport::TimeWithZone.new(@utc.to_datetime, @time_zone)
   end
@@ -29,25 +31,31 @@ class TimeWithZoneTest < ActiveSupport::TestCase
   end
 
   def test_in_time_zone
-    Time.use_zone 'Alaska' do
-      assert_equal ActiveSupport::TimeWithZone.new(@utc, ActiveSupport::TimeZone['Alaska']), @twz.in_time_zone
+    Time.use_zone "Alaska" do
+      assert_equal ActiveSupport::TimeWithZone.new(@utc, ActiveSupport::TimeZone["Alaska"]), @twz.in_time_zone
     end
   end
 
   def test_in_time_zone_with_argument
-    assert_equal ActiveSupport::TimeWithZone.new(@utc, ActiveSupport::TimeZone['Alaska']), @twz.in_time_zone('Alaska')
+    assert_equal ActiveSupport::TimeWithZone.new(@utc, ActiveSupport::TimeZone["Alaska"]), @twz.in_time_zone("Alaska")
   end
 
   def test_in_time_zone_with_new_zone_equal_to_old_zone_does_not_create_new_object
-    assert_equal @twz.object_id, @twz.in_time_zone(ActiveSupport::TimeZone['Eastern Time (US & Canada)']).object_id
+    assert_equal @twz.object_id, @twz.in_time_zone(ActiveSupport::TimeZone["Eastern Time (US & Canada)"]).object_id
   end
 
   def test_in_time_zone_with_bad_argument
-    assert_raise(ArgumentError) { @twz.in_time_zone('No such timezone exists') }
+    assert_raise(ArgumentError) { @twz.in_time_zone("No such timezone exists") }
     assert_raise(ArgumentError) { @twz.in_time_zone(-15.hours) }
     assert_raise(ArgumentError) { @twz.in_time_zone(Object.new) }
   end
 
+  def test_in_time_zone_with_ambiguous_time
+    with_env_tz "Europe/Moscow" do
+      assert_equal Time.utc(2014, 10, 25, 22, 0, 0), Time.local(2014, 10, 26, 1, 0, 0).in_time_zone("Moscow")
+    end
+  end
+
   def test_localtime
     assert_equal @twz.localtime, @twz.utc.getlocal
     assert_instance_of Time, @twz.localtime
@@ -57,26 +65,26 @@ class TimeWithZoneTest < ActiveSupport::TestCase
   def test_utc?
     assert_equal false, @twz.utc?
 
-    assert_equal true, ActiveSupport::TimeWithZone.new(Time.utc(2000), ActiveSupport::TimeZone['UTC']).utc?
-    assert_equal true, ActiveSupport::TimeWithZone.new(Time.utc(2000), ActiveSupport::TimeZone['Etc/UTC']).utc?
-    assert_equal true, ActiveSupport::TimeWithZone.new(Time.utc(2000), ActiveSupport::TimeZone['Universal']).utc?
-    assert_equal true, ActiveSupport::TimeWithZone.new(Time.utc(2000), ActiveSupport::TimeZone['UCT']).utc?
-    assert_equal true, ActiveSupport::TimeWithZone.new(Time.utc(2000), ActiveSupport::TimeZone['Etc/UCT']).utc?
-    assert_equal true, ActiveSupport::TimeWithZone.new(Time.utc(2000), ActiveSupport::TimeZone['Etc/Universal']).utc?
+    assert_equal true, ActiveSupport::TimeWithZone.new(Time.utc(2000), ActiveSupport::TimeZone["UTC"]).utc?
+    assert_equal true, ActiveSupport::TimeWithZone.new(Time.utc(2000), ActiveSupport::TimeZone["Etc/UTC"]).utc?
+    assert_equal true, ActiveSupport::TimeWithZone.new(Time.utc(2000), ActiveSupport::TimeZone["Universal"]).utc?
+    assert_equal true, ActiveSupport::TimeWithZone.new(Time.utc(2000), ActiveSupport::TimeZone["UCT"]).utc?
+    assert_equal true, ActiveSupport::TimeWithZone.new(Time.utc(2000), ActiveSupport::TimeZone["Etc/UCT"]).utc?
+    assert_equal true, ActiveSupport::TimeWithZone.new(Time.utc(2000), ActiveSupport::TimeZone["Etc/Universal"]).utc?
 
-    assert_equal false, ActiveSupport::TimeWithZone.new(Time.utc(2000), ActiveSupport::TimeZone['Africa/Abidjan']).utc?
-    assert_equal false, ActiveSupport::TimeWithZone.new(Time.utc(2000), ActiveSupport::TimeZone['Africa/Banjul']).utc?
-    assert_equal false, ActiveSupport::TimeWithZone.new(Time.utc(2000), ActiveSupport::TimeZone['Africa/Freetown']).utc?
-    assert_equal false, ActiveSupport::TimeWithZone.new(Time.utc(2000), ActiveSupport::TimeZone['GMT']).utc?
-    assert_equal false, ActiveSupport::TimeWithZone.new(Time.utc(2000), ActiveSupport::TimeZone['GMT0']).utc?
-    assert_equal false, ActiveSupport::TimeWithZone.new(Time.utc(2000), ActiveSupport::TimeZone['Greenwich']).utc?
-    assert_equal false, ActiveSupport::TimeWithZone.new(Time.utc(2000), ActiveSupport::TimeZone['Iceland']).utc?
-    assert_equal false, ActiveSupport::TimeWithZone.new(Time.utc(2000), ActiveSupport::TimeZone['Africa/Monrovia']).utc?
+    assert_equal false, ActiveSupport::TimeWithZone.new(Time.utc(2000), ActiveSupport::TimeZone["Africa/Abidjan"]).utc?
+    assert_equal false, ActiveSupport::TimeWithZone.new(Time.utc(2000), ActiveSupport::TimeZone["Africa/Banjul"]).utc?
+    assert_equal false, ActiveSupport::TimeWithZone.new(Time.utc(2000), ActiveSupport::TimeZone["Africa/Freetown"]).utc?
+    assert_equal false, ActiveSupport::TimeWithZone.new(Time.utc(2000), ActiveSupport::TimeZone["GMT"]).utc?
+    assert_equal false, ActiveSupport::TimeWithZone.new(Time.utc(2000), ActiveSupport::TimeZone["GMT0"]).utc?
+    assert_equal false, ActiveSupport::TimeWithZone.new(Time.utc(2000), ActiveSupport::TimeZone["Greenwich"]).utc?
+    assert_equal false, ActiveSupport::TimeWithZone.new(Time.utc(2000), ActiveSupport::TimeZone["Iceland"]).utc?
+    assert_equal false, ActiveSupport::TimeWithZone.new(Time.utc(2000), ActiveSupport::TimeZone["Africa/Monrovia"]).utc?
   end
 
   def test_formatted_offset
-    assert_equal '-05:00', @twz.formatted_offset
-    assert_equal '-04:00', ActiveSupport::TimeWithZone.new(Time.utc(2000, 6), @time_zone).formatted_offset #dst
+    assert_equal "-05:00", @twz.formatted_offset
+    assert_equal "-04:00", ActiveSupport::TimeWithZone.new(Time.utc(2000, 6), @time_zone).formatted_offset # dst
   end
 
   def test_dst?
@@ -85,12 +93,12 @@ class TimeWithZoneTest < ActiveSupport::TestCase
   end
 
   def test_zone
-    assert_equal 'EST', @twz.zone
-    assert_equal 'EDT', ActiveSupport::TimeWithZone.new(Time.utc(2000, 6), @time_zone).zone #dst
+    assert_equal "EST", @twz.zone
+    assert_equal "EDT", ActiveSupport::TimeWithZone.new(Time.utc(2000, 6), @time_zone).zone # dst
   end
 
   def test_nsec
-    local     = Time.local(2011,6,7,23,59,59,Rational(999999999, 1000))
+    local     = Time.local(2011, 6, 7, 23, 59, 59, Rational(999999999, 1000))
     with_zone = ActiveSupport::TimeWithZone.new(nil, ActiveSupport::TimeZone["Hawaii"], local)
 
     assert_equal local.nsec, with_zone.nsec
@@ -98,28 +106,28 @@ class TimeWithZoneTest < ActiveSupport::TestCase
   end
 
   def test_strftime
-    assert_equal '1999-12-31 19:00:00 EST -0500', @twz.strftime('%Y-%m-%d %H:%M:%S %Z %z')
+    assert_equal "1999-12-31 19:00:00 EST -0500", @twz.strftime("%Y-%m-%d %H:%M:%S %Z %z")
   end
 
   def test_strftime_with_escaping
-    assert_equal '%Z %z', @twz.strftime('%%Z %%z')
-    assert_equal '%EST %-0500', @twz.strftime('%%%Z %%%z')
+    assert_equal "%Z %z", @twz.strftime("%%Z %%z")
+    assert_equal "%EST %-0500", @twz.strftime("%%%Z %%%z")
   end
 
   def test_inspect
-    assert_equal 'Fri, 31 Dec 1999 19:00:00 EST -05:00', @twz.inspect
+    assert_equal "Fri, 31 Dec 1999 19:00:00 EST -05:00", @twz.inspect
   end
 
   def test_to_s
-    assert_equal '1999-12-31 19:00:00 -0500', @twz.to_s
+    assert_equal "1999-12-31 19:00:00 -0500", @twz.to_s
   end
 
   def test_to_formatted_s
-    assert_equal '1999-12-31 19:00:00 -0500', @twz.to_formatted_s
+    assert_equal "1999-12-31 19:00:00 -0500", @twz.to_formatted_s
   end
 
   def test_to_s_db
-    assert_equal '2000-01-01 00:00:00', @twz.to_s(:db)
+    assert_equal "2000-01-01 00:00:00", @twz.to_s(:db)
   end
 
   def test_xmlschema
@@ -144,6 +152,16 @@ class TimeWithZoneTest < ActiveSupport::TestCase
     assert_equal "1999-12-31T19:00:00-05:00", @twz.xmlschema(nil)
   end
 
+  def test_iso8601_with_fractional_seconds
+    @twz += Rational(1, 8)
+    assert_equal "1999-12-31T19:00:00.125-05:00", @twz.iso8601(3)
+  end
+
+  def test_rfc3339_with_fractional_seconds
+    @twz += Rational(1, 8)
+    assert_equal "1999-12-31T19:00:00.125-05:00", @twz.rfc3339(3)
+  end
+
   def test_to_yaml
     yaml = <<-EOF.strip_heredoc
       --- !ruby/object:ActiveSupport::TimeWithZone
@@ -166,7 +184,7 @@ class TimeWithZoneTest < ActiveSupport::TestCase
         time: 1999-12-31 19:00:00.000000000 Z
     EOF
 
-    assert_equal(yaml, { 'twz' => @twz }.to_yaml)
+    assert_equal(yaml, { "twz" => @twz }.to_yaml)
   end
 
   def test_yaml_load
@@ -191,11 +209,11 @@ class TimeWithZoneTest < ActiveSupport::TestCase
         time: 1999-12-31 19:00:00.000000000 Z
     EOF
 
-    assert_equal({ 'twz' => @twz }, YAML.load(yaml))
+    assert_equal({ "twz" => @twz }, YAML.load(yaml))
   end
 
   def test_httpdate
-    assert_equal 'Sat, 01 Jan 2000 00:00:00 GMT', @twz.httpdate
+    assert_equal "Sat, 01 Jan 2000 00:00:00 GMT", @twz.httpdate
   end
 
   def test_rfc2822
@@ -215,69 +233,69 @@ class TimeWithZoneTest < ActiveSupport::TestCase
   end
 
   def test_compare_with_time_with_zone
-    assert_equal  1, @twz <=> ActiveSupport::TimeWithZone.new( Time.utc(1999, 12, 31, 23, 59, 59), ActiveSupport::TimeZone['UTC'] )
-    assert_equal  0, @twz <=> ActiveSupport::TimeWithZone.new( Time.utc(2000, 1, 1, 0, 0, 0), ActiveSupport::TimeZone['UTC'] )
-    assert_equal(-1, @twz <=> ActiveSupport::TimeWithZone.new( Time.utc(2000, 1, 1, 0, 0, 1), ActiveSupport::TimeZone['UTC'] ))
+    assert_equal  1, @twz <=> ActiveSupport::TimeWithZone.new(Time.utc(1999, 12, 31, 23, 59, 59), ActiveSupport::TimeZone["UTC"])
+    assert_equal  0, @twz <=> ActiveSupport::TimeWithZone.new(Time.utc(2000, 1, 1, 0, 0, 0), ActiveSupport::TimeZone["UTC"])
+    assert_equal(-1, @twz <=> ActiveSupport::TimeWithZone.new(Time.utc(2000, 1, 1, 0, 0, 1), ActiveSupport::TimeZone["UTC"]))
   end
 
   def test_between?
-    assert @twz.between?(Time.utc(1999,12,31,23,59,59), Time.utc(2000,1,1,0,0,1))
-    assert_equal false, @twz.between?(Time.utc(2000,1,1,0,0,1), Time.utc(2000,1,1,0,0,2))
+    assert @twz.between?(Time.utc(1999, 12, 31, 23, 59, 59), Time.utc(2000, 1, 1, 0, 0, 1))
+    assert_equal false, @twz.between?(Time.utc(2000, 1, 1, 0, 0, 1), Time.utc(2000, 1, 1, 0, 0, 2))
   end
 
   def test_today
     Date.stub(:current, Date.new(2000, 1, 1)) do
-      assert_equal false, ActiveSupport::TimeWithZone.new( nil, @time_zone, Time.utc(1999,12,31,23,59,59) ).today?
-      assert_equal true, ActiveSupport::TimeWithZone.new( nil, @time_zone, Time.utc(2000,1,1,0) ).today?
-      assert_equal true, ActiveSupport::TimeWithZone.new( nil, @time_zone, Time.utc(2000,1,1,23,59,59) ).today?
-      assert_equal false, ActiveSupport::TimeWithZone.new( nil, @time_zone, Time.utc(2000,1,2,0) ).today?
+      assert_equal false, ActiveSupport::TimeWithZone.new(nil, @time_zone, Time.utc(1999, 12, 31, 23, 59, 59)).today?
+      assert_equal true, ActiveSupport::TimeWithZone.new(nil, @time_zone, Time.utc(2000, 1, 1, 0)).today?
+      assert_equal true, ActiveSupport::TimeWithZone.new(nil, @time_zone, Time.utc(2000, 1, 1, 23, 59, 59)).today?
+      assert_equal false, ActiveSupport::TimeWithZone.new(nil, @time_zone, Time.utc(2000, 1, 2, 0)).today?
     end
   end
 
   def test_past_with_time_current_as_time_local
-    with_env_tz 'US/Eastern' do
-      Time.stub(:current, Time.local(2005,2,10,15,30,45)) do
-        assert_equal true, ActiveSupport::TimeWithZone.new( nil, @time_zone, Time.local(2005,2,10,15,30,44)).past?
-        assert_equal false, ActiveSupport::TimeWithZone.new( nil, @time_zone, Time.local(2005,2,10,15,30,45)).past?
-        assert_equal false, ActiveSupport::TimeWithZone.new( nil, @time_zone, Time.local(2005,2,10,15,30,46)).past?
+    with_env_tz "US/Eastern" do
+      Time.stub(:current, Time.local(2005, 2, 10, 15, 30, 45)) do
+        assert_equal true, ActiveSupport::TimeWithZone.new(nil, @time_zone, Time.local(2005, 2, 10, 15, 30, 44)).past?
+        assert_equal false, ActiveSupport::TimeWithZone.new(nil, @time_zone, Time.local(2005, 2, 10, 15, 30, 45)).past?
+        assert_equal false, ActiveSupport::TimeWithZone.new(nil, @time_zone, Time.local(2005, 2, 10, 15, 30, 46)).past?
       end
     end
   end
 
   def test_past_with_time_current_as_time_with_zone
-    twz = ActiveSupport::TimeWithZone.new( nil, @time_zone, Time.local(2005,2,10,15,30,45) )
+    twz = ActiveSupport::TimeWithZone.new(nil, @time_zone, Time.local(2005, 2, 10, 15, 30, 45))
     Time.stub(:current, twz) do
-      assert_equal true, ActiveSupport::TimeWithZone.new( nil, @time_zone, Time.local(2005,2,10,15,30,44)).past?
-      assert_equal false, ActiveSupport::TimeWithZone.new( nil, @time_zone, Time.local(2005,2,10,15,30,45)).past?
-      assert_equal false, ActiveSupport::TimeWithZone.new( nil, @time_zone, Time.local(2005,2,10,15,30,46)).past?
+      assert_equal true, ActiveSupport::TimeWithZone.new(nil, @time_zone, Time.local(2005, 2, 10, 15, 30, 44)).past?
+      assert_equal false, ActiveSupport::TimeWithZone.new(nil, @time_zone, Time.local(2005, 2, 10, 15, 30, 45)).past?
+      assert_equal false, ActiveSupport::TimeWithZone.new(nil, @time_zone, Time.local(2005, 2, 10, 15, 30, 46)).past?
     end
   end
 
   def test_future_with_time_current_as_time_local
-    with_env_tz 'US/Eastern' do
-      Time.stub(:current, Time.local(2005,2,10,15,30,45)) do
-        assert_equal false, ActiveSupport::TimeWithZone.new( nil, @time_zone, Time.local(2005,2,10,15,30,44)).future?
-        assert_equal false, ActiveSupport::TimeWithZone.new( nil, @time_zone, Time.local(2005,2,10,15,30,45)).future?
-        assert_equal true, ActiveSupport::TimeWithZone.new( nil, @time_zone, Time.local(2005,2,10,15,30,46)).future?
+    with_env_tz "US/Eastern" do
+      Time.stub(:current, Time.local(2005, 2, 10, 15, 30, 45)) do
+        assert_equal false, ActiveSupport::TimeWithZone.new(nil, @time_zone, Time.local(2005, 2, 10, 15, 30, 44)).future?
+        assert_equal false, ActiveSupport::TimeWithZone.new(nil, @time_zone, Time.local(2005, 2, 10, 15, 30, 45)).future?
+        assert_equal true, ActiveSupport::TimeWithZone.new(nil, @time_zone, Time.local(2005, 2, 10, 15, 30, 46)).future?
       end
     end
   end
 
   def test_future_with_time_current_as_time_with_zone
-    twz = ActiveSupport::TimeWithZone.new( nil, @time_zone, Time.local(2005,2,10,15,30,45) )
+    twz = ActiveSupport::TimeWithZone.new(nil, @time_zone, Time.local(2005, 2, 10, 15, 30, 45))
     Time.stub(:current, twz) do
-      assert_equal false, ActiveSupport::TimeWithZone.new( nil, @time_zone, Time.local(2005,2,10,15,30,44)).future?
-      assert_equal false, ActiveSupport::TimeWithZone.new( nil, @time_zone, Time.local(2005,2,10,15,30,45)).future?
-      assert_equal true, ActiveSupport::TimeWithZone.new( nil, @time_zone, Time.local(2005,2,10,15,30,46)).future?
+      assert_equal false, ActiveSupport::TimeWithZone.new(nil, @time_zone, Time.local(2005, 2, 10, 15, 30, 44)).future?
+      assert_equal false, ActiveSupport::TimeWithZone.new(nil, @time_zone, Time.local(2005, 2, 10, 15, 30, 45)).future?
+      assert_equal true, ActiveSupport::TimeWithZone.new(nil, @time_zone, Time.local(2005, 2, 10, 15, 30, 46)).future?
     end
   end
 
   def test_eql?
     assert_equal true, @twz.eql?(@twz.dup)
     assert_equal true, @twz.eql?(Time.utc(2000))
-    assert_equal true, @twz.eql?( ActiveSupport::TimeWithZone.new(Time.utc(2000), ActiveSupport::TimeZone["Hawaii"]) )
-    assert_equal false, @twz.eql?( Time.utc(2000, 1, 1, 0, 0, 1) )
-    assert_equal false, @twz.eql?( DateTime.civil(1999, 12, 31, 23, 59, 59) )
+    assert_equal true, @twz.eql?(ActiveSupport::TimeWithZone.new(Time.utc(2000), ActiveSupport::TimeZone["Hawaii"]))
+    assert_equal false, @twz.eql?(Time.utc(2000, 1, 1, 0, 0, 1))
+    assert_equal false, @twz.eql?(DateTime.civil(1999, 12, 31, 23, 59, 59))
 
     other_twz = ActiveSupport::TimeWithZone.new(DateTime.now.utc, @time_zone)
     assert_equal true, other_twz.eql?(other_twz.dup)
@@ -289,117 +307,117 @@ class TimeWithZoneTest < ActiveSupport::TestCase
   end
 
   def test_plus_with_integer
-    assert_equal Time.utc(1999, 12, 31, 19, 0 ,5), (@twz + 5).time
+    assert_equal Time.utc(1999, 12, 31, 19, 0, 5), (@twz + 5).time
   end
 
   def test_plus_with_integer_when_self_wraps_datetime
     datetime = DateTime.civil(2000, 1, 1, 0)
     twz = ActiveSupport::TimeWithZone.new(datetime, @time_zone)
-    assert_equal DateTime.civil(1999, 12, 31, 19, 0 ,5), (twz + 5).time
+    assert_equal DateTime.civil(1999, 12, 31, 19, 0, 5), (twz + 5).time
   end
 
   def test_plus_when_crossing_time_class_limit
     twz = ActiveSupport::TimeWithZone.new(Time.utc(2038, 1, 19), @time_zone)
-    assert_equal [0, 0, 19, 19, 1, 2038], (twz + 86_400).to_a[0,6]
+    assert_equal [0, 0, 19, 19, 1, 2038], (twz + 86_400).to_a[0, 6]
   end
 
   def test_plus_with_duration
-    assert_equal Time.utc(2000, 1, 5, 19, 0 ,0), (@twz + 5.days).time
+    assert_equal Time.utc(2000, 1, 5, 19, 0, 0), (@twz + 5.days).time
   end
 
   def test_minus_with_integer
-    assert_equal Time.utc(1999, 12, 31, 18, 59 ,55), (@twz - 5).time
+    assert_equal Time.utc(1999, 12, 31, 18, 59, 55), (@twz - 5).time
   end
 
   def test_minus_with_integer_when_self_wraps_datetime
     datetime = DateTime.civil(2000, 1, 1, 0)
     twz = ActiveSupport::TimeWithZone.new(datetime, @time_zone)
-    assert_equal DateTime.civil(1999, 12, 31, 18, 59 ,55), (twz - 5).time
+    assert_equal DateTime.civil(1999, 12, 31, 18, 59, 55), (twz - 5).time
   end
 
   def test_minus_with_duration
-    assert_equal Time.utc(1999, 12, 26, 19, 0 ,0), (@twz - 5.days).time
+    assert_equal Time.utc(1999, 12, 26, 19, 0, 0), (@twz - 5.days).time
   end
 
   def test_minus_with_time
-    assert_equal  86_400.0,  ActiveSupport::TimeWithZone.new( Time.utc(2000, 1, 2), ActiveSupport::TimeZone['UTC'] ) - Time.utc(2000, 1, 1)
-    assert_equal  86_400.0,  ActiveSupport::TimeWithZone.new( Time.utc(2000, 1, 2), ActiveSupport::TimeZone['Hawaii'] ) - Time.utc(2000, 1, 1)
+    assert_equal  86_400.0,  ActiveSupport::TimeWithZone.new(Time.utc(2000, 1, 2), ActiveSupport::TimeZone["UTC"]) - Time.utc(2000, 1, 1)
+    assert_equal  86_400.0,  ActiveSupport::TimeWithZone.new(Time.utc(2000, 1, 2), ActiveSupport::TimeZone["Hawaii"]) - Time.utc(2000, 1, 1)
   end
 
   def test_minus_with_time_precision
-    assert_equal  86_399.999999998,  ActiveSupport::TimeWithZone.new( Time.utc(2000, 1, 2, 23, 59, 59, Rational(999999999, 1000)), ActiveSupport::TimeZone['UTC'] ) - Time.utc(2000, 1, 2, 0, 0, 0, Rational(1, 1000))
-    assert_equal  86_399.999999998,  ActiveSupport::TimeWithZone.new( Time.utc(2000, 1, 2, 23, 59, 59, Rational(999999999, 1000)), ActiveSupport::TimeZone['Hawaii'] ) - Time.utc(2000, 1, 2, 0, 0, 0, Rational(1, 1000))
+    assert_equal  86_399.999999998,  ActiveSupport::TimeWithZone.new(Time.utc(2000, 1, 2, 23, 59, 59, Rational(999999999, 1000)), ActiveSupport::TimeZone["UTC"]) - Time.utc(2000, 1, 2, 0, 0, 0, Rational(1, 1000))
+    assert_equal  86_399.999999998,  ActiveSupport::TimeWithZone.new(Time.utc(2000, 1, 2, 23, 59, 59, Rational(999999999, 1000)), ActiveSupport::TimeZone["Hawaii"]) - Time.utc(2000, 1, 2, 0, 0, 0, Rational(1, 1000))
   end
 
   def test_minus_with_time_with_zone
-    twz1 = ActiveSupport::TimeWithZone.new( Time.utc(2000, 1, 1), ActiveSupport::TimeZone['UTC'] )
-    twz2 = ActiveSupport::TimeWithZone.new( Time.utc(2000, 1, 2), ActiveSupport::TimeZone['UTC'] )
-    assert_equal  86_400.0,  twz2 - twz1
+    twz1 = ActiveSupport::TimeWithZone.new(Time.utc(2000, 1, 1), ActiveSupport::TimeZone["UTC"])
+    twz2 = ActiveSupport::TimeWithZone.new(Time.utc(2000, 1, 2), ActiveSupport::TimeZone["UTC"])
+    assert_equal 86_400.0,  twz2 - twz1
   end
 
   def test_minus_with_time_with_zone_precision
-    twz1 = ActiveSupport::TimeWithZone.new( Time.utc(2000, 1, 1, 0, 0, 0, Rational(1, 1000)), ActiveSupport::TimeZone['UTC'] )
-    twz2 = ActiveSupport::TimeWithZone.new( Time.utc(2000, 1, 1, 23, 59, 59, Rational(999999999, 1000)), ActiveSupport::TimeZone['UTC'] )
+    twz1 = ActiveSupport::TimeWithZone.new(Time.utc(2000, 1, 1, 0, 0, 0, Rational(1, 1000)), ActiveSupport::TimeZone["UTC"])
+    twz2 = ActiveSupport::TimeWithZone.new(Time.utc(2000, 1, 1, 23, 59, 59, Rational(999999999, 1000)), ActiveSupport::TimeZone["UTC"])
     assert_equal  86_399.999999998,  twz2 - twz1
   end
 
   def test_minus_with_datetime
-    assert_equal  86_400.0,  ActiveSupport::TimeWithZone.new( Time.utc(2000, 1, 2), ActiveSupport::TimeZone['UTC'] ) - DateTime.civil(2000, 1, 1)
+    assert_equal  86_400.0,  ActiveSupport::TimeWithZone.new(Time.utc(2000, 1, 2), ActiveSupport::TimeZone["UTC"]) - DateTime.civil(2000, 1, 1)
   end
 
   def test_minus_with_datetime_precision
-    assert_equal  86_399.999999999,  ActiveSupport::TimeWithZone.new( Time.utc(2000, 1, 1, 23, 59, 59, Rational(999999999, 1000)), ActiveSupport::TimeZone['UTC'] ) - DateTime.civil(2000, 1, 1)
+    assert_equal  86_399.999999999,  ActiveSupport::TimeWithZone.new(Time.utc(2000, 1, 1, 23, 59, 59, Rational(999999999, 1000)), ActiveSupport::TimeZone["UTC"]) - DateTime.civil(2000, 1, 1)
   end
 
   def test_minus_with_wrapped_datetime
-    assert_equal  86_400.0,  ActiveSupport::TimeWithZone.new( DateTime.civil(2000, 1, 2), ActiveSupport::TimeZone['UTC'] ) - Time.utc(2000, 1, 1)
-    assert_equal  86_400.0,  ActiveSupport::TimeWithZone.new( DateTime.civil(2000, 1, 2), ActiveSupport::TimeZone['UTC'] ) - DateTime.civil(2000, 1, 1)
+    assert_equal  86_400.0,  ActiveSupport::TimeWithZone.new(DateTime.civil(2000, 1, 2), ActiveSupport::TimeZone["UTC"]) - Time.utc(2000, 1, 1)
+    assert_equal  86_400.0,  ActiveSupport::TimeWithZone.new(DateTime.civil(2000, 1, 2), ActiveSupport::TimeZone["UTC"]) - DateTime.civil(2000, 1, 1)
   end
 
   def test_plus_and_minus_enforce_spring_dst_rules
-    utc = Time.utc(2006,4,2,6,59,59) # == Apr 2 2006 01:59:59 EST; i.e., 1 second before daylight savings start
+    utc = Time.utc(2006, 4, 2, 6, 59, 59) # == Apr 2 2006 01:59:59 EST; i.e., 1 second before daylight savings start
     twz = ActiveSupport::TimeWithZone.new(utc, @time_zone)
-    assert_equal Time.utc(2006,4,2,1,59,59), twz.time
+    assert_equal Time.utc(2006, 4, 2, 1, 59, 59), twz.time
     assert_equal false, twz.dst?
-    assert_equal 'EST', twz.zone
+    assert_equal "EST", twz.zone
     twz = twz + 1
-    assert_equal Time.utc(2006,4,2,3), twz.time # adding 1 sec springs forward to 3:00AM EDT
+    assert_equal Time.utc(2006, 4, 2, 3), twz.time # adding 1 sec springs forward to 3:00AM EDT
     assert_equal true, twz.dst?
-    assert_equal 'EDT', twz.zone
+    assert_equal "EDT", twz.zone
     twz = twz - 1 # subtracting 1 second takes goes back to 1:59:59AM EST
-    assert_equal Time.utc(2006,4,2,1,59,59), twz.time
+    assert_equal Time.utc(2006, 4, 2, 1, 59, 59), twz.time
     assert_equal false, twz.dst?
-    assert_equal 'EST', twz.zone
+    assert_equal "EST", twz.zone
   end
 
   def test_plus_and_minus_enforce_fall_dst_rules
-    utc = Time.utc(2006,10,29,5,59,59) # == Oct 29 2006 01:59:59 EST; i.e., 1 second before daylight savings end
+    utc = Time.utc(2006, 10, 29, 5, 59, 59) # == Oct 29 2006 01:59:59 EST; i.e., 1 second before daylight savings end
     twz = ActiveSupport::TimeWithZone.new(utc, @time_zone)
-    assert_equal Time.utc(2006,10,29,1,59,59), twz.time
+    assert_equal Time.utc(2006, 10, 29, 1, 59, 59), twz.time
     assert_equal true, twz.dst?
-    assert_equal 'EDT', twz.zone
+    assert_equal "EDT", twz.zone
     twz = twz + 1
-    assert_equal Time.utc(2006,10,29,1), twz.time # adding 1 sec falls back from 1:59:59 EDT to 1:00AM EST
+    assert_equal Time.utc(2006, 10, 29, 1), twz.time # adding 1 sec falls back from 1:59:59 EDT to 1:00AM EST
     assert_equal false, twz.dst?
-    assert_equal 'EST', twz.zone
+    assert_equal "EST", twz.zone
     twz = twz - 1
-    assert_equal Time.utc(2006,10,29,1,59,59), twz.time # subtracting 1 sec goes back to 1:59:59AM EDT
+    assert_equal Time.utc(2006, 10, 29, 1, 59, 59), twz.time # subtracting 1 sec goes back to 1:59:59AM EDT
     assert_equal true, twz.dst?
-    assert_equal 'EDT', twz.zone
+    assert_equal "EDT", twz.zone
   end
 
   def test_to_a
-    assert_equal [45, 30, 5, 1, 2, 2000, 2, 32, false, "HST"], ActiveSupport::TimeWithZone.new( Time.utc(2000, 2, 1, 15, 30, 45), ActiveSupport::TimeZone['Hawaii'] ).to_a
+    assert_equal [45, 30, 5, 1, 2, 2000, 2, 32, false, "HST"], ActiveSupport::TimeWithZone.new(Time.utc(2000, 2, 1, 15, 30, 45), ActiveSupport::TimeZone["Hawaii"]).to_a
   end
 
   def test_to_f
-    result = ActiveSupport::TimeWithZone.new( Time.utc(2000, 1, 1), ActiveSupport::TimeZone['Hawaii'] ).to_f
+    result = ActiveSupport::TimeWithZone.new(Time.utc(2000, 1, 1), ActiveSupport::TimeZone["Hawaii"]).to_f
     assert_equal 946684800.0, result
     assert_kind_of Float, result
   end
 
   def test_to_i
-    result = ActiveSupport::TimeWithZone.new( Time.utc(2000, 1, 1), ActiveSupport::TimeZone['Hawaii'] ).to_i
+    result = ActiveSupport::TimeWithZone.new(Time.utc(2000, 1, 1), ActiveSupport::TimeZone["Hawaii"]).to_i
     assert_equal 946684800, result
     assert_kind_of Integer, result
   end
@@ -411,33 +429,51 @@ class TimeWithZoneTest < ActiveSupport::TestCase
   end
 
   def test_to_r
-    result = ActiveSupport::TimeWithZone.new(Time.utc(2000, 1, 1), ActiveSupport::TimeZone['Hawaii']).to_r
+    result = ActiveSupport::TimeWithZone.new(Time.utc(2000, 1, 1), ActiveSupport::TimeZone["Hawaii"]).to_r
     assert_equal Rational(946684800, 1), result
     assert_kind_of Rational, result
   end
 
   def test_time_at
-    time = ActiveSupport::TimeWithZone.new(Time.utc(2000, 1, 1), ActiveSupport::TimeZone['Hawaii'])
+    time = ActiveSupport::TimeWithZone.new(Time.utc(2000, 1, 1), ActiveSupport::TimeZone["Hawaii"])
     assert_equal time, Time.at(time)
   end
 
-  def test_to_time
-    with_env_tz 'US/Eastern' do
-      assert_equal Time, @twz.to_time.class
-      assert_equal Time.local(1999, 12, 31, 19), @twz.to_time
-      assert_equal Time.local(1999, 12, 31, 19).utc_offset, @twz.to_time.utc_offset
+  def test_to_time_with_preserve_timezone
+    with_preserve_timezone(true) do
+      with_env_tz "US/Eastern" do
+        time = @twz.to_time
+
+        assert_equal Time, time.class
+        assert_equal time.object_id, @twz.to_time.object_id
+        assert_equal Time.local(1999, 12, 31, 19), time
+        assert_equal Time.local(1999, 12, 31, 19).utc_offset, time.utc_offset
+      end
+    end
+  end
+
+  def test_to_time_without_preserve_timezone
+    with_preserve_timezone(false) do
+      with_env_tz "US/Eastern" do
+        time = @twz.to_time
+
+        assert_equal Time, time.class
+        assert_equal time.object_id, @twz.to_time.object_id
+        assert_equal Time.local(1999, 12, 31, 19), time
+        assert_equal Time.local(1999, 12, 31, 19).utc_offset, time.utc_offset
+      end
     end
   end
 
   def test_to_date
     # 1 sec before midnight Jan 1 EST
-    assert_equal Date.new(1999, 12, 31), ActiveSupport::TimeWithZone.new( Time.utc(2000, 1, 1, 4, 59, 59), ActiveSupport::TimeZone['Eastern Time (US & Canada)'] ).to_date
+    assert_equal Date.new(1999, 12, 31), ActiveSupport::TimeWithZone.new(Time.utc(2000, 1, 1, 4, 59, 59), ActiveSupport::TimeZone["Eastern Time (US & Canada)"]).to_date
     # midnight Jan 1 EST
-    assert_equal Date.new(2000,  1,  1), ActiveSupport::TimeWithZone.new( Time.utc(2000, 1, 1, 5,  0,  0), ActiveSupport::TimeZone['Eastern Time (US & Canada)'] ).to_date
+    assert_equal Date.new(2000,  1,  1), ActiveSupport::TimeWithZone.new(Time.utc(2000, 1, 1, 5,  0,  0), ActiveSupport::TimeZone["Eastern Time (US & Canada)"]).to_date
     # 1 sec before midnight Jan 2 EST
-    assert_equal Date.new(2000,  1,  1), ActiveSupport::TimeWithZone.new( Time.utc(2000, 1, 2, 4, 59, 59), ActiveSupport::TimeZone['Eastern Time (US & Canada)'] ).to_date
+    assert_equal Date.new(2000,  1,  1), ActiveSupport::TimeWithZone.new(Time.utc(2000, 1, 2, 4, 59, 59), ActiveSupport::TimeZone["Eastern Time (US & Canada)"]).to_date
     # midnight Jan 2 EST
-    assert_equal Date.new(2000,  1,  2), ActiveSupport::TimeWithZone.new( Time.utc(2000, 1, 2, 5,  0,  0), ActiveSupport::TimeZone['Eastern Time (US & Canada)'] ).to_date
+    assert_equal Date.new(2000,  1,  2), ActiveSupport::TimeWithZone.new(Time.utc(2000, 1, 2, 5,  0,  0), ActiveSupport::TimeZone["Eastern Time (US & Canada)"]).to_date
   end
 
   def test_to_datetime
@@ -455,6 +491,10 @@ class TimeWithZoneTest < ActiveSupport::TestCase
     assert_equal false, ActiveSupport::TimeWithZone.new(DateTime.civil(2000), @time_zone).acts_like?(:date)
   end
 
+  def test_blank?
+    assert_not @twz.blank?
+  end
+
   def test_is_a
     assert_kind_of Time, @twz
     assert_kind_of Time, @twz
@@ -462,12 +502,12 @@ class TimeWithZoneTest < ActiveSupport::TestCase
   end
 
   def test_class_name
-    assert_equal 'Time', ActiveSupport::TimeWithZone.name
+    assert_equal "Time", ActiveSupport::TimeWithZone.name
   end
 
   def test_method_missing_with_time_return_value
     assert_instance_of ActiveSupport::TimeWithZone, @twz.months_since(1)
-    assert_equal Time.utc(2000, 1, 31, 19, 0 ,0), @twz.months_since(1).time
+    assert_equal Time.utc(2000, 1, 31, 19, 0, 0), @twz.months_since(1).time
   end
 
   def test_marshal_dump_and_load
@@ -475,19 +515,19 @@ class TimeWithZoneTest < ActiveSupport::TestCase
     mtime = Marshal.load(marshal_str)
     assert_equal Time.utc(2000, 1, 1, 0), mtime.utc
     assert mtime.utc.utc?
-    assert_equal ActiveSupport::TimeZone['Eastern Time (US & Canada)'], mtime.time_zone
+    assert_equal ActiveSupport::TimeZone["Eastern Time (US & Canada)"], mtime.time_zone
     assert_equal Time.utc(1999, 12, 31, 19), mtime.time
     assert mtime.time.utc?
     assert_equal @twz.inspect, mtime.inspect
   end
 
   def test_marshal_dump_and_load_with_tzinfo_identifier
-    twz = ActiveSupport::TimeWithZone.new(@utc, TZInfo::Timezone.get('America/New_York'))
+    twz = ActiveSupport::TimeWithZone.new(@utc, TZInfo::Timezone.get("America/New_York"))
     marshal_str = Marshal.dump(twz)
     mtime = Marshal.load(marshal_str)
     assert_equal Time.utc(2000, 1, 1, 0), mtime.utc
     assert mtime.utc.utc?
-    assert_equal 'America/New_York', mtime.time_zone.name
+    assert_equal "America/New_York", mtime.time_zone.name
     assert_equal Time.utc(1999, 12, 31, 19), mtime.time
     assert mtime.time.utc?
     assert_equal @twz.inspect, mtime.inspect
@@ -503,17 +543,19 @@ class TimeWithZoneTest < ActiveSupport::TestCase
     assert_nothing_raised do
       @twz.period
       @twz.time
+      @twz.to_datetime
+      @twz.to_time
     end
   end
 
   def test_method_missing_with_non_time_return_value
     time = @twz.time
-    def time.foo; 'bar'; end
-    assert_equal 'bar', @twz.foo
+    def time.foo; "bar"; end
+    assert_equal "bar", @twz.foo
   end
 
   def test_date_part_value_methods
-    twz = ActiveSupport::TimeWithZone.new(Time.utc(1999,12,31,19,18,17,500), @time_zone)
+    twz = ActiveSupport::TimeWithZone.new(Time.utc(1999, 12, 31, 19, 18, 17, 500), @time_zone)
     assert_not_called(twz, :method_missing) do
       assert_equal 1999, twz.year
       assert_equal 12, twz.month
@@ -533,19 +575,19 @@ class TimeWithZoneTest < ActiveSupport::TestCase
   end
 
   def test_usec_returns_sec_fraction_when_datetime_is_wrapped
-    twz = ActiveSupport::TimeWithZone.new(DateTime.civil(2000, 1, 1, 0, 0, Rational(1,2)), @time_zone)
+    twz = ActiveSupport::TimeWithZone.new(DateTime.civil(2000, 1, 1, 0, 0, Rational(1, 2)), @time_zone)
     assert_equal 500000, twz.usec
   end
 
   def test_nsec_returns_sec_fraction_when_datetime_is_wrapped
-    twz = ActiveSupport::TimeWithZone.new(DateTime.civil(2000, 1, 1, 0, 0, Rational(1,2)), @time_zone)
+    twz = ActiveSupport::TimeWithZone.new(DateTime.civil(2000, 1, 1, 0, 0, Rational(1, 2)), @time_zone)
     assert_equal 500000000, twz.nsec
   end
 
   def test_utc_to_local_conversion_saves_period_in_instance_variable
-    assert_nil @twz.instance_variable_get('@period')
+    assert_nil @twz.instance_variable_get("@period")
     @twz.time
-    assert_kind_of TZInfo::TimezonePeriod, @twz.instance_variable_get('@period')
+    assert_kind_of TZInfo::TimezonePeriod, @twz.instance_variable_get("@period")
   end
 
   def test_instance_created_with_local_time_returns_correct_utc_time
@@ -554,17 +596,17 @@ class TimeWithZoneTest < ActiveSupport::TestCase
   end
 
   def test_instance_created_with_local_time_enforces_spring_dst_rules
-    twz = ActiveSupport::TimeWithZone.new(nil, @time_zone, Time.utc(2006,4,2,2)) # first second of DST
-    assert_equal Time.utc(2006,4,2,3), twz.time # springs forward to 3AM
+    twz = ActiveSupport::TimeWithZone.new(nil, @time_zone, Time.utc(2006, 4, 2, 2)) # first second of DST
+    assert_equal Time.utc(2006, 4, 2, 3), twz.time # springs forward to 3AM
     assert_equal true, twz.dst?
-    assert_equal 'EDT', twz.zone
+    assert_equal "EDT", twz.zone
   end
 
   def test_instance_created_with_local_time_enforces_fall_dst_rules
-    twz = ActiveSupport::TimeWithZone.new(nil, @time_zone, Time.utc(2006,10,29,1)) # 1AM can be either DST or non-DST; we'll pick DST
-    assert_equal Time.utc(2006,10,29,1), twz.time
+    twz = ActiveSupport::TimeWithZone.new(nil, @time_zone, Time.utc(2006, 10, 29, 1)) # 1AM can be either DST or non-DST; we'll pick DST
+    assert_equal Time.utc(2006, 10, 29, 1), twz.time
     assert_equal true, twz.dst?
-    assert_equal 'EDT', twz.zone
+    assert_equal "EDT", twz.zone
   end
 
   def test_ruby_19_weekday_name_query_methods
@@ -575,42 +617,48 @@ class TimeWithZoneTest < ActiveSupport::TestCase
   end
 
   def test_utc_to_local_conversion_with_far_future_datetime
-    assert_equal [0,0,19,31,12,2049], ActiveSupport::TimeWithZone.new(DateTime.civil(2050), @time_zone).to_a[0,6]
+    assert_equal [0, 0, 19, 31, 12, 2049], ActiveSupport::TimeWithZone.new(DateTime.civil(2050), @time_zone).to_a[0, 6]
   end
 
   def test_local_to_utc_conversion_with_far_future_datetime
-    assert_equal DateTime.civil(2050).to_f, ActiveSupport::TimeWithZone.new(nil, @time_zone, DateTime.civil(2049,12,31,19)).to_f
+    assert_equal DateTime.civil(2050).to_f, ActiveSupport::TimeWithZone.new(nil, @time_zone, DateTime.civil(2049, 12, 31, 19)).to_f
   end
 
   def test_change
     assert_equal "Fri, 31 Dec 1999 19:00:00 EST -05:00", @twz.inspect
-    assert_equal "Mon, 31 Dec 2001 19:00:00 EST -05:00", @twz.change(:year => 2001).inspect
-    assert_equal "Wed, 31 Mar 1999 19:00:00 EST -05:00", @twz.change(:month => 3).inspect
-    assert_equal "Wed, 03 Mar 1999 19:00:00 EST -05:00", @twz.change(:month => 2).inspect
-    assert_equal "Wed, 15 Dec 1999 19:00:00 EST -05:00", @twz.change(:day => 15).inspect
-    assert_equal "Fri, 31 Dec 1999 06:00:00 EST -05:00", @twz.change(:hour => 6).inspect
-    assert_equal "Fri, 31 Dec 1999 19:15:00 EST -05:00", @twz.change(:min => 15).inspect
-    assert_equal "Fri, 31 Dec 1999 19:00:30 EST -05:00", @twz.change(:sec => 30).inspect
+    assert_equal "Mon, 31 Dec 2001 19:00:00 EST -05:00", @twz.change(year: 2001).inspect
+    assert_equal "Wed, 31 Mar 1999 19:00:00 EST -05:00", @twz.change(month: 3).inspect
+    assert_equal "Wed, 03 Mar 1999 19:00:00 EST -05:00", @twz.change(month: 2).inspect
+    assert_equal "Wed, 15 Dec 1999 19:00:00 EST -05:00", @twz.change(day: 15).inspect
+    assert_equal "Fri, 31 Dec 1999 06:00:00 EST -05:00", @twz.change(hour: 6).inspect
+    assert_equal "Fri, 31 Dec 1999 19:15:00 EST -05:00", @twz.change(min: 15).inspect
+    assert_equal "Fri, 31 Dec 1999 19:00:30 EST -05:00", @twz.change(sec: 30).inspect
+    assert_equal "Fri, 31 Dec 1999 19:00:00 HST -10:00", @twz.change(offset: "-10:00").inspect
+    assert_equal "Fri, 31 Dec 1999 19:00:00 HST -10:00", @twz.change(offset: -36000).inspect
+    assert_equal "Fri, 31 Dec 1999 19:00:00 HST -10:00", @twz.change(zone: "Hawaii").inspect
+    assert_equal "Fri, 31 Dec 1999 19:00:00 HST -10:00", @twz.change(zone: -10).inspect
+    assert_equal "Fri, 31 Dec 1999 19:00:00 HST -10:00", @twz.change(zone: -36000).inspect
+    assert_equal "Fri, 31 Dec 1999 19:00:00 HST -10:00", @twz.change(zone: "Pacific/Honolulu").inspect
   end
 
   def test_change_at_dst_boundary
-    twz = ActiveSupport::TimeWithZone.new(Time.at(1319936400).getutc, ActiveSupport::TimeZone['Madrid'])
-    assert_equal twz, twz.change(:min => 0)
+    twz = ActiveSupport::TimeWithZone.new(Time.at(1319936400).getutc, ActiveSupport::TimeZone["Madrid"])
+    assert_equal twz, twz.change(min: 0)
   end
 
   def test_round_at_dst_boundary
-    twz = ActiveSupport::TimeWithZone.new(Time.at(1319936400).getutc, ActiveSupport::TimeZone['Madrid'])
+    twz = ActiveSupport::TimeWithZone.new(Time.at(1319936400).getutc, ActiveSupport::TimeZone["Madrid"])
     assert_equal twz, twz.round
   end
 
   def test_advance
     assert_equal "Fri, 31 Dec 1999 19:00:00 EST -05:00", @twz.inspect
-    assert_equal "Mon, 31 Dec 2001 19:00:00 EST -05:00", @twz.advance(:years => 2).inspect
-    assert_equal "Fri, 31 Mar 2000 19:00:00 EST -05:00", @twz.advance(:months => 3).inspect
-    assert_equal "Tue, 04 Jan 2000 19:00:00 EST -05:00", @twz.advance(:days => 4).inspect
-    assert_equal "Sat, 01 Jan 2000 01:00:00 EST -05:00", @twz.advance(:hours => 6).inspect
-    assert_equal "Fri, 31 Dec 1999 19:15:00 EST -05:00", @twz.advance(:minutes => 15).inspect
-    assert_equal "Fri, 31 Dec 1999 19:00:30 EST -05:00", @twz.advance(:seconds => 30).inspect
+    assert_equal "Mon, 31 Dec 2001 19:00:00 EST -05:00", @twz.advance(years: 2).inspect
+    assert_equal "Fri, 31 Mar 2000 19:00:00 EST -05:00", @twz.advance(months: 3).inspect
+    assert_equal "Tue, 04 Jan 2000 19:00:00 EST -05:00", @twz.advance(days: 4).inspect
+    assert_equal "Sat, 01 Jan 2000 01:00:00 EST -05:00", @twz.advance(hours: 6).inspect
+    assert_equal "Fri, 31 Dec 1999 19:15:00 EST -05:00", @twz.advance(minutes: 15).inspect
+    assert_equal "Fri, 31 Dec 1999 19:00:30 EST -05:00", @twz.advance(seconds: 30).inspect
   end
 
   def test_beginning_of_year
@@ -675,6 +723,10 @@ class TimeWithZoneTest < ActiveSupport::TestCase
     assert_equal "Fri, 31 Dec 1999 19:00:01 EST -05:00", @twz.since(1).inspect
   end
 
+  def test_in
+    assert_equal "Fri, 31 Dec 1999 19:00:01 EST -05:00", @twz.in(1).inspect
+  end
+
   def test_ago
     assert_equal "Fri, 31 Dec 1999 18:59:59 EST -05:00", @twz.ago(1).inspect
   end
@@ -684,204 +736,262 @@ class TimeWithZoneTest < ActiveSupport::TestCase
   end
 
   def test_advance_1_year_from_leap_day
-    twz = ActiveSupport::TimeWithZone.new(nil, @time_zone, Time.utc(2004,2,29))
-    assert_equal "Mon, 28 Feb 2005 00:00:00 EST -05:00", twz.advance(:years => 1).inspect
+    twz = ActiveSupport::TimeWithZone.new(nil, @time_zone, Time.utc(2004, 2, 29))
+    assert_equal "Mon, 28 Feb 2005 00:00:00 EST -05:00", twz.advance(years: 1).inspect
     assert_equal "Mon, 28 Feb 2005 00:00:00 EST -05:00", twz.years_since(1).inspect
     assert_equal "Mon, 28 Feb 2005 00:00:00 EST -05:00", twz.since(1.year).inspect
+    assert_equal "Mon, 28 Feb 2005 00:00:00 EST -05:00", twz.in(1.year).inspect
     assert_equal "Mon, 28 Feb 2005 00:00:00 EST -05:00", (twz + 1.year).inspect
   end
 
   def test_advance_1_month_from_last_day_of_january
-    twz = ActiveSupport::TimeWithZone.new(nil, @time_zone, Time.utc(2005,1,31))
-    assert_equal "Mon, 28 Feb 2005 00:00:00 EST -05:00", twz.advance(:months => 1).inspect
+    twz = ActiveSupport::TimeWithZone.new(nil, @time_zone, Time.utc(2005, 1, 31))
+    assert_equal "Mon, 28 Feb 2005 00:00:00 EST -05:00", twz.advance(months: 1).inspect
     assert_equal "Mon, 28 Feb 2005 00:00:00 EST -05:00", twz.months_since(1).inspect
     assert_equal "Mon, 28 Feb 2005 00:00:00 EST -05:00", twz.since(1.month).inspect
+    assert_equal "Mon, 28 Feb 2005 00:00:00 EST -05:00", twz.in(1.month).inspect
     assert_equal "Mon, 28 Feb 2005 00:00:00 EST -05:00", (twz + 1.month).inspect
   end
 
   def test_advance_1_month_from_last_day_of_january_during_leap_year
-    twz = ActiveSupport::TimeWithZone.new(nil, @time_zone, Time.utc(2000,1,31))
-    assert_equal "Tue, 29 Feb 2000 00:00:00 EST -05:00", twz.advance(:months => 1).inspect
+    twz = ActiveSupport::TimeWithZone.new(nil, @time_zone, Time.utc(2000, 1, 31))
+    assert_equal "Tue, 29 Feb 2000 00:00:00 EST -05:00", twz.advance(months: 1).inspect
     assert_equal "Tue, 29 Feb 2000 00:00:00 EST -05:00", twz.months_since(1).inspect
     assert_equal "Tue, 29 Feb 2000 00:00:00 EST -05:00", twz.since(1.month).inspect
+    assert_equal "Tue, 29 Feb 2000 00:00:00 EST -05:00", twz.in(1.month).inspect
     assert_equal "Tue, 29 Feb 2000 00:00:00 EST -05:00", (twz + 1.month).inspect
   end
 
   def test_advance_1_month_into_spring_dst_gap
-    twz = ActiveSupport::TimeWithZone.new(nil, @time_zone, Time.utc(2006,3,2,2))
-    assert_equal "Sun, 02 Apr 2006 03:00:00 EDT -04:00", twz.advance(:months => 1).inspect
+    twz = ActiveSupport::TimeWithZone.new(nil, @time_zone, Time.utc(2006, 3, 2, 2))
+    assert_equal "Sun, 02 Apr 2006 03:00:00 EDT -04:00", twz.advance(months: 1).inspect
     assert_equal "Sun, 02 Apr 2006 03:00:00 EDT -04:00", twz.months_since(1).inspect
     assert_equal "Sun, 02 Apr 2006 03:00:00 EDT -04:00", twz.since(1.month).inspect
+    assert_equal "Sun, 02 Apr 2006 03:00:00 EDT -04:00", twz.in(1.month).inspect
     assert_equal "Sun, 02 Apr 2006 03:00:00 EDT -04:00", (twz + 1.month).inspect
   end
 
   def test_advance_1_second_into_spring_dst_gap
-    twz = ActiveSupport::TimeWithZone.new(nil, @time_zone, Time.utc(2006,4,2,1,59,59))
-    assert_equal "Sun, 02 Apr 2006 03:00:00 EDT -04:00", twz.advance(:seconds => 1).inspect
+    twz = ActiveSupport::TimeWithZone.new(nil, @time_zone, Time.utc(2006, 4, 2, 1, 59, 59))
+    assert_equal "Sun, 02 Apr 2006 03:00:00 EDT -04:00", twz.advance(seconds: 1).inspect
     assert_equal "Sun, 02 Apr 2006 03:00:00 EDT -04:00", (twz + 1).inspect
+    assert_equal "Sun, 02 Apr 2006 03:00:00 EDT -04:00", (twz + 1.second).inspect
     assert_equal "Sun, 02 Apr 2006 03:00:00 EDT -04:00", twz.since(1).inspect
     assert_equal "Sun, 02 Apr 2006 03:00:00 EDT -04:00", twz.since(1.second).inspect
-    assert_equal "Sun, 02 Apr 2006 03:00:00 EDT -04:00", (twz + 1.second).inspect
+    assert_equal "Sun, 02 Apr 2006 03:00:00 EDT -04:00", twz.in(1).inspect
+    assert_equal "Sun, 02 Apr 2006 03:00:00 EDT -04:00", twz.in(1.second).inspect
   end
 
   def test_advance_1_day_across_spring_dst_transition
-    twz = ActiveSupport::TimeWithZone.new(nil, @time_zone, Time.utc(2006,4,1,10,30))
+    twz = ActiveSupport::TimeWithZone.new(nil, @time_zone, Time.utc(2006, 4, 1, 10, 30))
     # In 2006, spring DST transition occurred Apr 2 at 2AM; this day was only 23 hours long
     # When we advance 1 day, we want to end up at the same time on the next day
-    assert_equal "Sun, 02 Apr 2006 10:30:00 EDT -04:00", twz.advance(:days => 1).inspect
+    assert_equal "Sun, 02 Apr 2006 10:30:00 EDT -04:00", twz.advance(days: 1).inspect
     assert_equal "Sun, 02 Apr 2006 10:30:00 EDT -04:00", twz.since(1.days).inspect
+    assert_equal "Sun, 02 Apr 2006 10:30:00 EDT -04:00", twz.in(1.days).inspect
     assert_equal "Sun, 02 Apr 2006 10:30:00 EDT -04:00", (twz + 1.days).inspect
     assert_equal "Sun, 02 Apr 2006 10:30:01 EDT -04:00", twz.since(1.days + 1.second).inspect
+    assert_equal "Sun, 02 Apr 2006 10:30:01 EDT -04:00", twz.in(1.days + 1.second).inspect
     assert_equal "Sun, 02 Apr 2006 10:30:01 EDT -04:00", (twz + 1.days + 1.second).inspect
   end
 
   def test_advance_1_day_across_spring_dst_transition_backwards
-    twz = ActiveSupport::TimeWithZone.new(nil, @time_zone, Time.utc(2006,4,2,10,30))
+    twz = ActiveSupport::TimeWithZone.new(nil, @time_zone, Time.utc(2006, 4, 2, 10, 30))
     # In 2006, spring DST transition occurred Apr 2 at 2AM; this day was only 23 hours long
     # When we advance back 1 day, we want to end up at the same time on the previous day
-    assert_equal "Sat, 01 Apr 2006 10:30:00 EST -05:00", twz.advance(:days => -1).inspect
+    assert_equal "Sat, 01 Apr 2006 10:30:00 EST -05:00", twz.advance(days: -1).inspect
     assert_equal "Sat, 01 Apr 2006 10:30:00 EST -05:00", twz.ago(1.days).inspect
     assert_equal "Sat, 01 Apr 2006 10:30:00 EST -05:00", (twz - 1.days).inspect
     assert_equal "Sat, 01 Apr 2006 10:30:01 EST -05:00", twz.ago(1.days - 1.second).inspect
   end
 
   def test_advance_1_day_expressed_as_number_of_seconds_minutes_or_hours_across_spring_dst_transition
-    twz = ActiveSupport::TimeWithZone.new(nil, @time_zone, Time.utc(2006,4,1,10,30))
+    twz = ActiveSupport::TimeWithZone.new(nil, @time_zone, Time.utc(2006, 4, 1, 10, 30))
     # In 2006, spring DST transition occurred Apr 2 at 2AM; this day was only 23 hours long
     # When we advance a specific number of hours, minutes or seconds, we want to advance exactly that amount
     assert_equal "Sun, 02 Apr 2006 11:30:00 EDT -04:00", (twz + 86400).inspect
     assert_equal "Sun, 02 Apr 2006 11:30:00 EDT -04:00", (twz + 86400.seconds).inspect
     assert_equal "Sun, 02 Apr 2006 11:30:00 EDT -04:00", twz.since(86400).inspect
     assert_equal "Sun, 02 Apr 2006 11:30:00 EDT -04:00", twz.since(86400.seconds).inspect
-    assert_equal "Sun, 02 Apr 2006 11:30:00 EDT -04:00", twz.advance(:seconds => 86400).inspect
+    assert_equal "Sun, 02 Apr 2006 11:30:00 EDT -04:00", twz.in(86400).inspect
+    assert_equal "Sun, 02 Apr 2006 11:30:00 EDT -04:00", twz.in(86400.seconds).inspect
+    assert_equal "Sun, 02 Apr 2006 11:30:00 EDT -04:00", twz.advance(seconds: 86400).inspect
     assert_equal "Sun, 02 Apr 2006 11:30:00 EDT -04:00", (twz + 1440.minutes).inspect
     assert_equal "Sun, 02 Apr 2006 11:30:00 EDT -04:00", twz.since(1440.minutes).inspect
-    assert_equal "Sun, 02 Apr 2006 11:30:00 EDT -04:00", twz.advance(:minutes => 1440).inspect
+    assert_equal "Sun, 02 Apr 2006 11:30:00 EDT -04:00", twz.in(1440.minutes).inspect
+    assert_equal "Sun, 02 Apr 2006 11:30:00 EDT -04:00", twz.advance(minutes: 1440).inspect
     assert_equal "Sun, 02 Apr 2006 11:30:00 EDT -04:00", (twz + 24.hours).inspect
     assert_equal "Sun, 02 Apr 2006 11:30:00 EDT -04:00", twz.since(24.hours).inspect
-    assert_equal "Sun, 02 Apr 2006 11:30:00 EDT -04:00", twz.advance(:hours => 24).inspect
+    assert_equal "Sun, 02 Apr 2006 11:30:00 EDT -04:00", twz.in(24.hours).inspect
+    assert_equal "Sun, 02 Apr 2006 11:30:00 EDT -04:00", twz.advance(hours: 24).inspect
   end
 
   def test_advance_1_day_expressed_as_number_of_seconds_minutes_or_hours_across_spring_dst_transition_backwards
-    twz = ActiveSupport::TimeWithZone.new(nil, @time_zone, Time.utc(2006,4,2,11,30))
+    twz = ActiveSupport::TimeWithZone.new(nil, @time_zone, Time.utc(2006, 4, 2, 11, 30))
     # In 2006, spring DST transition occurred Apr 2 at 2AM; this day was only 23 hours long
     # When we advance a specific number of hours, minutes or seconds, we want to advance exactly that amount
     assert_equal "Sat, 01 Apr 2006 10:30:00 EST -05:00", (twz - 86400).inspect
     assert_equal "Sat, 01 Apr 2006 10:30:00 EST -05:00", (twz - 86400.seconds).inspect
     assert_equal "Sat, 01 Apr 2006 10:30:00 EST -05:00", twz.ago(86400).inspect
     assert_equal "Sat, 01 Apr 2006 10:30:00 EST -05:00", twz.ago(86400.seconds).inspect
-    assert_equal "Sat, 01 Apr 2006 10:30:00 EST -05:00", twz.advance(:seconds => -86400).inspect
+    assert_equal "Sat, 01 Apr 2006 10:30:00 EST -05:00", twz.advance(seconds: -86400).inspect
     assert_equal "Sat, 01 Apr 2006 10:30:00 EST -05:00", (twz - 1440.minutes).inspect
     assert_equal "Sat, 01 Apr 2006 10:30:00 EST -05:00", twz.ago(1440.minutes).inspect
-    assert_equal "Sat, 01 Apr 2006 10:30:00 EST -05:00", twz.advance(:minutes => -1440).inspect
+    assert_equal "Sat, 01 Apr 2006 10:30:00 EST -05:00", twz.advance(minutes: -1440).inspect
     assert_equal "Sat, 01 Apr 2006 10:30:00 EST -05:00", (twz - 24.hours).inspect
     assert_equal "Sat, 01 Apr 2006 10:30:00 EST -05:00", twz.ago(24.hours).inspect
-    assert_equal "Sat, 01 Apr 2006 10:30:00 EST -05:00", twz.advance(:hours => -24).inspect
+    assert_equal "Sat, 01 Apr 2006 10:30:00 EST -05:00", twz.advance(hours: -24).inspect
   end
 
   def test_advance_1_day_across_fall_dst_transition
-    twz = ActiveSupport::TimeWithZone.new(nil, @time_zone, Time.utc(2006,10,28,10,30))
+    twz = ActiveSupport::TimeWithZone.new(nil, @time_zone, Time.utc(2006, 10, 28, 10, 30))
     # In 2006, fall DST transition occurred Oct 29 at 2AM; this day was 25 hours long
     # When we advance 1 day, we want to end up at the same time on the next day
-    assert_equal "Sun, 29 Oct 2006 10:30:00 EST -05:00", twz.advance(:days => 1).inspect
+    assert_equal "Sun, 29 Oct 2006 10:30:00 EST -05:00", twz.advance(days: 1).inspect
     assert_equal "Sun, 29 Oct 2006 10:30:00 EST -05:00", twz.since(1.days).inspect
+    assert_equal "Sun, 29 Oct 2006 10:30:00 EST -05:00", twz.in(1.days).inspect
     assert_equal "Sun, 29 Oct 2006 10:30:00 EST -05:00", (twz + 1.days).inspect
     assert_equal "Sun, 29 Oct 2006 10:30:01 EST -05:00", twz.since(1.days + 1.second).inspect
+    assert_equal "Sun, 29 Oct 2006 10:30:01 EST -05:00", twz.in(1.days + 1.second).inspect
     assert_equal "Sun, 29 Oct 2006 10:30:01 EST -05:00", (twz + 1.days + 1.second).inspect
   end
 
   def test_advance_1_day_across_fall_dst_transition_backwards
-    twz = ActiveSupport::TimeWithZone.new(nil, @time_zone, Time.utc(2006,10,29,10,30))
+    twz = ActiveSupport::TimeWithZone.new(nil, @time_zone, Time.utc(2006, 10, 29, 10, 30))
     # In 2006, fall DST transition occurred Oct 29 at 2AM; this day was 25 hours long
     # When we advance backwards 1 day, we want to end up at the same time on the previous day
-    assert_equal "Sat, 28 Oct 2006 10:30:00 EDT -04:00", twz.advance(:days => -1).inspect
+    assert_equal "Sat, 28 Oct 2006 10:30:00 EDT -04:00", twz.advance(days: -1).inspect
     assert_equal "Sat, 28 Oct 2006 10:30:00 EDT -04:00", twz.ago(1.days).inspect
     assert_equal "Sat, 28 Oct 2006 10:30:00 EDT -04:00", (twz - 1.days).inspect
     assert_equal "Sat, 28 Oct 2006 10:30:01 EDT -04:00", twz.ago(1.days - 1.second).inspect
   end
 
   def test_advance_1_day_expressed_as_number_of_seconds_minutes_or_hours_across_fall_dst_transition
-    twz = ActiveSupport::TimeWithZone.new(nil, @time_zone, Time.utc(2006,10,28,10,30))
+    twz = ActiveSupport::TimeWithZone.new(nil, @time_zone, Time.utc(2006, 10, 28, 10, 30))
     # In 2006, fall DST transition occurred Oct 29 at 2AM; this day was 25 hours long
     # When we advance a specific number of hours, minutes or seconds, we want to advance exactly that amount
     assert_equal "Sun, 29 Oct 2006 09:30:00 EST -05:00", (twz + 86400).inspect
     assert_equal "Sun, 29 Oct 2006 09:30:00 EST -05:00", (twz + 86400.seconds).inspect
     assert_equal "Sun, 29 Oct 2006 09:30:00 EST -05:00", twz.since(86400).inspect
     assert_equal "Sun, 29 Oct 2006 09:30:00 EST -05:00", twz.since(86400.seconds).inspect
-    assert_equal "Sun, 29 Oct 2006 09:30:00 EST -05:00", twz.advance(:seconds => 86400).inspect
+    assert_equal "Sun, 29 Oct 2006 09:30:00 EST -05:00", twz.in(86400).inspect
+    assert_equal "Sun, 29 Oct 2006 09:30:00 EST -05:00", twz.in(86400.seconds).inspect
+    assert_equal "Sun, 29 Oct 2006 09:30:00 EST -05:00", twz.advance(seconds: 86400).inspect
     assert_equal "Sun, 29 Oct 2006 09:30:00 EST -05:00", (twz + 1440.minutes).inspect
     assert_equal "Sun, 29 Oct 2006 09:30:00 EST -05:00", twz.since(1440.minutes).inspect
-    assert_equal "Sun, 29 Oct 2006 09:30:00 EST -05:00", twz.advance(:minutes => 1440).inspect
+    assert_equal "Sun, 29 Oct 2006 09:30:00 EST -05:00", twz.in(1440.minutes).inspect
+    assert_equal "Sun, 29 Oct 2006 09:30:00 EST -05:00", twz.advance(minutes: 1440).inspect
     assert_equal "Sun, 29 Oct 2006 09:30:00 EST -05:00", (twz + 24.hours).inspect
     assert_equal "Sun, 29 Oct 2006 09:30:00 EST -05:00", twz.since(24.hours).inspect
-    assert_equal "Sun, 29 Oct 2006 09:30:00 EST -05:00", twz.advance(:hours => 24).inspect
+    assert_equal "Sun, 29 Oct 2006 09:30:00 EST -05:00", twz.in(24.hours).inspect
+    assert_equal "Sun, 29 Oct 2006 09:30:00 EST -05:00", twz.advance(hours: 24).inspect
   end
 
   def test_advance_1_day_expressed_as_number_of_seconds_minutes_or_hours_across_fall_dst_transition_backwards
-    twz = ActiveSupport::TimeWithZone.new(nil, @time_zone, Time.utc(2006,10,29,9,30))
+    twz = ActiveSupport::TimeWithZone.new(nil, @time_zone, Time.utc(2006, 10, 29, 9, 30))
     # In 2006, fall DST transition occurred Oct 29 at 2AM; this day was 25 hours long
     # When we advance a specific number of hours, minutes or seconds, we want to advance exactly that amount
     assert_equal "Sat, 28 Oct 2006 10:30:00 EDT -04:00", (twz - 86400).inspect
     assert_equal "Sat, 28 Oct 2006 10:30:00 EDT -04:00", (twz - 86400.seconds).inspect
     assert_equal "Sat, 28 Oct 2006 10:30:00 EDT -04:00", twz.ago(86400).inspect
     assert_equal "Sat, 28 Oct 2006 10:30:00 EDT -04:00", twz.ago(86400.seconds).inspect
-    assert_equal "Sat, 28 Oct 2006 10:30:00 EDT -04:00", twz.advance(:seconds => -86400).inspect
+    assert_equal "Sat, 28 Oct 2006 10:30:00 EDT -04:00", twz.advance(seconds: -86400).inspect
     assert_equal "Sat, 28 Oct 2006 10:30:00 EDT -04:00", (twz - 1440.minutes).inspect
     assert_equal "Sat, 28 Oct 2006 10:30:00 EDT -04:00", twz.ago(1440.minutes).inspect
-    assert_equal "Sat, 28 Oct 2006 10:30:00 EDT -04:00", twz.advance(:minutes => -1440).inspect
+    assert_equal "Sat, 28 Oct 2006 10:30:00 EDT -04:00", twz.advance(minutes: -1440).inspect
     assert_equal "Sat, 28 Oct 2006 10:30:00 EDT -04:00", (twz - 24.hours).inspect
     assert_equal "Sat, 28 Oct 2006 10:30:00 EDT -04:00", twz.ago(24.hours).inspect
-    assert_equal "Sat, 28 Oct 2006 10:30:00 EDT -04:00", twz.advance(:hours => -24).inspect
+    assert_equal "Sat, 28 Oct 2006 10:30:00 EDT -04:00", twz.advance(hours: -24).inspect
+  end
+
+  def test_advance_1_week_across_spring_dst_transition
+    twz = ActiveSupport::TimeWithZone.new(nil, @time_zone, Time.utc(2006, 4, 1, 10, 30))
+    assert_equal "Sat, 08 Apr 2006 10:30:00 EDT -04:00", twz.advance(weeks: 1).inspect
+    assert_equal "Sat, 08 Apr 2006 10:30:00 EDT -04:00", twz.weeks_since(1).inspect
+    assert_equal "Sat, 08 Apr 2006 10:30:00 EDT -04:00", twz.since(1.week).inspect
+    assert_equal "Sat, 08 Apr 2006 10:30:00 EDT -04:00", twz.in(1.week).inspect
+    assert_equal "Sat, 08 Apr 2006 10:30:00 EDT -04:00", (twz + 1.week).inspect
+  end
+
+  def test_advance_1_week_across_spring_dst_transition_backwards
+    twz = ActiveSupport::TimeWithZone.new(nil, @time_zone, Time.utc(2006, 4, 8, 10, 30))
+    assert_equal "Sat, 01 Apr 2006 10:30:00 EST -05:00", twz.advance(weeks: -1).inspect
+    assert_equal "Sat, 01 Apr 2006 10:30:00 EST -05:00", twz.weeks_ago(1).inspect
+    assert_equal "Sat, 01 Apr 2006 10:30:00 EST -05:00", twz.ago(1.week).inspect
+    assert_equal "Sat, 01 Apr 2006 10:30:00 EST -05:00", (twz - 1.week).inspect
+  end
+
+  def test_advance_1_week_across_fall_dst_transition
+    twz = ActiveSupport::TimeWithZone.new(nil, @time_zone, Time.utc(2006, 10, 28, 10, 30))
+    assert_equal "Sat, 04 Nov 2006 10:30:00 EST -05:00", twz.advance(weeks: 1).inspect
+    assert_equal "Sat, 04 Nov 2006 10:30:00 EST -05:00", twz.weeks_since(1).inspect
+    assert_equal "Sat, 04 Nov 2006 10:30:00 EST -05:00", twz.since(1.week).inspect
+    assert_equal "Sat, 04 Nov 2006 10:30:00 EST -05:00", twz.in(1.week).inspect
+    assert_equal "Sat, 04 Nov 2006 10:30:00 EST -05:00", (twz + 1.week).inspect
+  end
+
+  def test_advance_1_week_across_fall_dst_transition_backwards
+    twz = ActiveSupport::TimeWithZone.new(nil, @time_zone, Time.utc(2006, 11, 4, 10, 30))
+    assert_equal "Sat, 28 Oct 2006 10:30:00 EDT -04:00", twz.advance(weeks: -1).inspect
+    assert_equal "Sat, 28 Oct 2006 10:30:00 EDT -04:00", twz.weeks_ago(1).inspect
+    assert_equal "Sat, 28 Oct 2006 10:30:00 EDT -04:00", twz.ago(1.week).inspect
+    assert_equal "Sat, 28 Oct 2006 10:30:00 EDT -04:00", (twz - 1.week).inspect
   end
 
   def test_advance_1_month_across_spring_dst_transition
-    twz = ActiveSupport::TimeWithZone.new(nil, @time_zone, Time.utc(2006,4,1,10,30))
-    assert_equal "Mon, 01 May 2006 10:30:00 EDT -04:00", twz.advance(:months => 1).inspect
+    twz = ActiveSupport::TimeWithZone.new(nil, @time_zone, Time.utc(2006, 4, 1, 10, 30))
+    assert_equal "Mon, 01 May 2006 10:30:00 EDT -04:00", twz.advance(months: 1).inspect
     assert_equal "Mon, 01 May 2006 10:30:00 EDT -04:00", twz.months_since(1).inspect
     assert_equal "Mon, 01 May 2006 10:30:00 EDT -04:00", twz.since(1.month).inspect
+    assert_equal "Mon, 01 May 2006 10:30:00 EDT -04:00", twz.in(1.month).inspect
     assert_equal "Mon, 01 May 2006 10:30:00 EDT -04:00", (twz + 1.month).inspect
   end
 
   def test_advance_1_month_across_spring_dst_transition_backwards
-    twz = ActiveSupport::TimeWithZone.new(nil, @time_zone, Time.utc(2006,5,1,10,30))
-    assert_equal "Sat, 01 Apr 2006 10:30:00 EST -05:00", twz.advance(:months => -1).inspect
+    twz = ActiveSupport::TimeWithZone.new(nil, @time_zone, Time.utc(2006, 5, 1, 10, 30))
+    assert_equal "Sat, 01 Apr 2006 10:30:00 EST -05:00", twz.advance(months: -1).inspect
     assert_equal "Sat, 01 Apr 2006 10:30:00 EST -05:00", twz.months_ago(1).inspect
     assert_equal "Sat, 01 Apr 2006 10:30:00 EST -05:00", twz.ago(1.month).inspect
     assert_equal "Sat, 01 Apr 2006 10:30:00 EST -05:00", (twz - 1.month).inspect
   end
 
   def test_advance_1_month_across_fall_dst_transition
-    twz = ActiveSupport::TimeWithZone.new(nil, @time_zone, Time.utc(2006,10,28,10,30))
-    assert_equal "Tue, 28 Nov 2006 10:30:00 EST -05:00", twz.advance(:months => 1).inspect
+    twz = ActiveSupport::TimeWithZone.new(nil, @time_zone, Time.utc(2006, 10, 28, 10, 30))
+    assert_equal "Tue, 28 Nov 2006 10:30:00 EST -05:00", twz.advance(months: 1).inspect
     assert_equal "Tue, 28 Nov 2006 10:30:00 EST -05:00", twz.months_since(1).inspect
     assert_equal "Tue, 28 Nov 2006 10:30:00 EST -05:00", twz.since(1.month).inspect
+    assert_equal "Tue, 28 Nov 2006 10:30:00 EST -05:00", twz.in(1.month).inspect
     assert_equal "Tue, 28 Nov 2006 10:30:00 EST -05:00", (twz + 1.month).inspect
   end
 
   def test_advance_1_month_across_fall_dst_transition_backwards
-    twz = ActiveSupport::TimeWithZone.new(nil, @time_zone, Time.utc(2006,11,28,10,30))
-    assert_equal "Sat, 28 Oct 2006 10:30:00 EDT -04:00", twz.advance(:months => -1).inspect
+    twz = ActiveSupport::TimeWithZone.new(nil, @time_zone, Time.utc(2006, 11, 28, 10, 30))
+    assert_equal "Sat, 28 Oct 2006 10:30:00 EDT -04:00", twz.advance(months: -1).inspect
     assert_equal "Sat, 28 Oct 2006 10:30:00 EDT -04:00", twz.months_ago(1).inspect
     assert_equal "Sat, 28 Oct 2006 10:30:00 EDT -04:00", twz.ago(1.month).inspect
     assert_equal "Sat, 28 Oct 2006 10:30:00 EDT -04:00", (twz - 1.month).inspect
   end
 
   def test_advance_1_year
-    twz = ActiveSupport::TimeWithZone.new(nil, @time_zone, Time.utc(2008,2,15,10,30))
-    assert_equal "Sun, 15 Feb 2009 10:30:00 EST -05:00", twz.advance(:years => 1).inspect
+    twz = ActiveSupport::TimeWithZone.new(nil, @time_zone, Time.utc(2008, 2, 15, 10, 30))
+    assert_equal "Sun, 15 Feb 2009 10:30:00 EST -05:00", twz.advance(years: 1).inspect
     assert_equal "Sun, 15 Feb 2009 10:30:00 EST -05:00", twz.years_since(1).inspect
+    assert_equal "Sun, 15 Feb 2009 10:30:00 EST -05:00", twz.since(1.year).inspect
+    assert_equal "Sun, 15 Feb 2009 10:30:00 EST -05:00", twz.in(1.year).inspect
     assert_equal "Sun, 15 Feb 2009 10:30:00 EST -05:00", (twz + 1.year).inspect
-    assert_equal "Thu, 15 Feb 2007 10:30:00 EST -05:00", twz.advance(:years => -1).inspect
+    assert_equal "Thu, 15 Feb 2007 10:30:00 EST -05:00", twz.advance(years: -1).inspect
     assert_equal "Thu, 15 Feb 2007 10:30:00 EST -05:00", twz.years_ago(1).inspect
     assert_equal "Thu, 15 Feb 2007 10:30:00 EST -05:00", (twz - 1.year).inspect
   end
 
   def test_advance_1_year_during_dst
-    twz = ActiveSupport::TimeWithZone.new(nil, @time_zone, Time.utc(2008,7,15,10,30))
-    assert_equal "Wed, 15 Jul 2009 10:30:00 EDT -04:00", twz.advance(:years => 1).inspect
+    twz = ActiveSupport::TimeWithZone.new(nil, @time_zone, Time.utc(2008, 7, 15, 10, 30))
+    assert_equal "Wed, 15 Jul 2009 10:30:00 EDT -04:00", twz.advance(years: 1).inspect
     assert_equal "Wed, 15 Jul 2009 10:30:00 EDT -04:00", twz.years_since(1).inspect
+    assert_equal "Wed, 15 Jul 2009 10:30:00 EDT -04:00", twz.since(1.year).inspect
+    assert_equal "Wed, 15 Jul 2009 10:30:00 EDT -04:00", twz.in(1.year).inspect
     assert_equal "Wed, 15 Jul 2009 10:30:00 EDT -04:00", (twz + 1.year).inspect
-    assert_equal "Sun, 15 Jul 2007 10:30:00 EDT -04:00", twz.advance(:years => -1).inspect
+    assert_equal "Sun, 15 Jul 2007 10:30:00 EDT -04:00", twz.advance(years: -1).inspect
     assert_equal "Sun, 15 Jul 2007 10:30:00 EDT -04:00", twz.years_ago(1).inspect
     assert_equal "Sun, 15 Jul 2007 10:30:00 EDT -04:00", (twz - 1.year).inspect
   end
@@ -909,13 +1019,13 @@ class TimeWithZoneMethodsForTimeAndDateTimeTest < ActiveSupport::TestCase
   end
 
   def test_in_time_zone
-    Time.use_zone 'Alaska' do
-      assert_equal 'Fri, 31 Dec 1999 15:00:00 AKST -09:00', @t.in_time_zone.inspect
-      assert_equal 'Fri, 31 Dec 1999 15:00:00 AKST -09:00', @dt.in_time_zone.inspect
+    Time.use_zone "Alaska" do
+      assert_equal "Fri, 31 Dec 1999 15:00:00 AKST -09:00", @t.in_time_zone.inspect
+      assert_equal "Fri, 31 Dec 1999 15:00:00 AKST -09:00", @dt.in_time_zone.inspect
     end
-    Time.use_zone 'Hawaii' do
-      assert_equal 'Fri, 31 Dec 1999 14:00:00 HST -10:00', @t.in_time_zone.inspect
-      assert_equal 'Fri, 31 Dec 1999 14:00:00 HST -10:00', @dt.in_time_zone.inspect
+    Time.use_zone "Hawaii" do
+      assert_equal "Fri, 31 Dec 1999 14:00:00 HST -10:00", @t.in_time_zone.inspect
+      assert_equal "Fri, 31 Dec 1999 14:00:00 HST -10:00", @dt.in_time_zone.inspect
     end
     Time.use_zone nil do
       assert_equal @t, @t.in_time_zone
@@ -925,20 +1035,20 @@ class TimeWithZoneMethodsForTimeAndDateTimeTest < ActiveSupport::TestCase
 
   def test_nil_time_zone
     Time.use_zone nil do
-      assert !@t.in_time_zone.respond_to?(:period), 'no period method'
-      assert !@dt.in_time_zone.respond_to?(:period), 'no period method'
+      assert !@t.in_time_zone.respond_to?(:period), "no period method"
+      assert !@dt.in_time_zone.respond_to?(:period), "no period method"
     end
   end
 
   def test_in_time_zone_with_argument
-    Time.use_zone 'Eastern Time (US & Canada)' do # Time.zone will not affect #in_time_zone(zone)
-      assert_equal 'Fri, 31 Dec 1999 15:00:00 AKST -09:00', @t.in_time_zone('Alaska').inspect
-      assert_equal 'Fri, 31 Dec 1999 15:00:00 AKST -09:00', @dt.in_time_zone('Alaska').inspect
-      assert_equal 'Fri, 31 Dec 1999 14:00:00 HST -10:00', @t.in_time_zone('Hawaii').inspect
-      assert_equal 'Fri, 31 Dec 1999 14:00:00 HST -10:00', @dt.in_time_zone('Hawaii').inspect
-      assert_equal 'Sat, 01 Jan 2000 00:00:00 UTC +00:00', @t.in_time_zone('UTC').inspect
-      assert_equal 'Sat, 01 Jan 2000 00:00:00 UTC +00:00', @dt.in_time_zone('UTC').inspect
-      assert_equal 'Fri, 31 Dec 1999 15:00:00 AKST -09:00', @t.in_time_zone(-9.hours).inspect
+    Time.use_zone "Eastern Time (US & Canada)" do # Time.zone will not affect #in_time_zone(zone)
+      assert_equal "Fri, 31 Dec 1999 15:00:00 AKST -09:00", @t.in_time_zone("Alaska").inspect
+      assert_equal "Fri, 31 Dec 1999 15:00:00 AKST -09:00", @dt.in_time_zone("Alaska").inspect
+      assert_equal "Fri, 31 Dec 1999 14:00:00 HST -10:00", @t.in_time_zone("Hawaii").inspect
+      assert_equal "Fri, 31 Dec 1999 14:00:00 HST -10:00", @dt.in_time_zone("Hawaii").inspect
+      assert_equal "Sat, 01 Jan 2000 00:00:00 UTC +00:00", @t.in_time_zone("UTC").inspect
+      assert_equal "Sat, 01 Jan 2000 00:00:00 UTC +00:00", @dt.in_time_zone("UTC").inspect
+      assert_equal "Fri, 31 Dec 1999 15:00:00 AKST -09:00", @t.in_time_zone(-9.hours).inspect
     end
   end
 
@@ -952,119 +1062,119 @@ class TimeWithZoneMethodsForTimeAndDateTimeTest < ActiveSupport::TestCase
   end
 
   def test_in_time_zone_with_time_local_instance
-    with_env_tz 'US/Eastern' do
+    with_env_tz "US/Eastern" do
       time = Time.local(1999, 12, 31, 19) # == Time.utc(2000)
-      assert_equal 'Fri, 31 Dec 1999 15:00:00 AKST -09:00', time.in_time_zone('Alaska').inspect
+      assert_equal "Fri, 31 Dec 1999 15:00:00 AKST -09:00", time.in_time_zone("Alaska").inspect
     end
   end
 
   def test_localtime
-    Time.zone = ActiveSupport::TimeZone['Eastern Time (US & Canada)']
+    Time.zone = ActiveSupport::TimeZone["Eastern Time (US & Canada)"]
     assert_equal @dt.in_time_zone.localtime, @dt.in_time_zone.utc.to_time.getlocal
   end
 
   def test_use_zone
-    Time.zone = 'Alaska'
-    Time.use_zone 'Hawaii' do
-      assert_equal ActiveSupport::TimeZone['Hawaii'], Time.zone
+    Time.zone = "Alaska"
+    Time.use_zone "Hawaii" do
+      assert_equal ActiveSupport::TimeZone["Hawaii"], Time.zone
     end
-    assert_equal ActiveSupport::TimeZone['Alaska'], Time.zone
+    assert_equal ActiveSupport::TimeZone["Alaska"], Time.zone
   end
 
   def test_use_zone_with_exception_raised
-    Time.zone = 'Alaska'
+    Time.zone = "Alaska"
     assert_raise RuntimeError do
-      Time.use_zone('Hawaii') { raise RuntimeError }
+      Time.use_zone("Hawaii") { raise RuntimeError }
     end
-    assert_equal ActiveSupport::TimeZone['Alaska'], Time.zone
+    assert_equal ActiveSupport::TimeZone["Alaska"], Time.zone
   end
 
   def test_use_zone_raises_on_invalid_timezone
-    Time.zone = 'Alaska'
+    Time.zone = "Alaska"
     assert_raise ArgumentError do
-      Time.use_zone("No such timezone exists") { }
+      Time.use_zone("No such timezone exists") {}
     end
-    assert_equal ActiveSupport::TimeZone['Alaska'], Time.zone
+    assert_equal ActiveSupport::TimeZone["Alaska"], Time.zone
   end
 
   def test_time_zone_getter_and_setter
-    Time.zone = ActiveSupport::TimeZone['Alaska']
-    assert_equal ActiveSupport::TimeZone['Alaska'], Time.zone
-    Time.zone = 'Alaska'
-    assert_equal ActiveSupport::TimeZone['Alaska'], Time.zone
+    Time.zone = ActiveSupport::TimeZone["Alaska"]
+    assert_equal ActiveSupport::TimeZone["Alaska"], Time.zone
+    Time.zone = "Alaska"
+    assert_equal ActiveSupport::TimeZone["Alaska"], Time.zone
     Time.zone = -9.hours
-    assert_equal ActiveSupport::TimeZone['Alaska'], Time.zone
+    assert_equal ActiveSupport::TimeZone["Alaska"], Time.zone
     Time.zone = nil
-    assert_equal nil, Time.zone
+    assert_nil Time.zone
   end
 
   def test_time_zone_getter_and_setter_with_zone_default_set
     old_zone_default = Time.zone_default
-    Time.zone_default = ActiveSupport::TimeZone['Alaska']
-    assert_equal ActiveSupport::TimeZone['Alaska'], Time.zone
-    Time.zone = ActiveSupport::TimeZone['Hawaii']
-    assert_equal ActiveSupport::TimeZone['Hawaii'], Time.zone
+    Time.zone_default = ActiveSupport::TimeZone["Alaska"]
+    assert_equal ActiveSupport::TimeZone["Alaska"], Time.zone
+    Time.zone = ActiveSupport::TimeZone["Hawaii"]
+    assert_equal ActiveSupport::TimeZone["Hawaii"], Time.zone
     Time.zone = nil
-    assert_equal ActiveSupport::TimeZone['Alaska'], Time.zone
+    assert_equal ActiveSupport::TimeZone["Alaska"], Time.zone
   ensure
     Time.zone_default = old_zone_default
   end
 
   def test_time_zone_setter_is_thread_safe
-    Time.use_zone 'Paris' do
-      t1 = Thread.new { Time.zone = 'Alaska' }.join
-      t2 = Thread.new { Time.zone = 'Hawaii' }.join
+    Time.use_zone "Paris" do
+      t1 = Thread.new { Time.zone = "Alaska" }.join
+      t2 = Thread.new { Time.zone = "Hawaii" }.join
       assert t1.stop?, "Thread 1 did not finish running"
       assert t2.stop?, "Thread 2 did not finish running"
-      assert_equal ActiveSupport::TimeZone['Paris'], Time.zone
-      assert_equal ActiveSupport::TimeZone['Alaska'], t1[:time_zone]
-      assert_equal ActiveSupport::TimeZone['Hawaii'], t2[:time_zone]
+      assert_equal ActiveSupport::TimeZone["Paris"], Time.zone
+      assert_equal ActiveSupport::TimeZone["Alaska"], t1[:time_zone]
+      assert_equal ActiveSupport::TimeZone["Hawaii"], t2[:time_zone]
     end
   end
 
   def test_time_zone_setter_with_tzinfo_timezone_object_wraps_in_rails_time_zone
-    tzinfo = TZInfo::Timezone.get('America/New_York')
+    tzinfo = TZInfo::Timezone.get("America/New_York")
     Time.zone = tzinfo
     assert_kind_of ActiveSupport::TimeZone, Time.zone
     assert_equal tzinfo, Time.zone.tzinfo
-    assert_equal 'America/New_York', Time.zone.name
+    assert_equal "America/New_York", Time.zone.name
     assert_equal(-18_000, Time.zone.utc_offset)
   end
 
   def test_time_zone_setter_with_tzinfo_timezone_identifier_does_lookup_and_wraps_in_rails_time_zone
-    Time.zone = 'America/New_York'
+    Time.zone = "America/New_York"
     assert_kind_of ActiveSupport::TimeZone, Time.zone
-    assert_equal 'America/New_York', Time.zone.tzinfo.name
-    assert_equal 'America/New_York', Time.zone.name
+    assert_equal "America/New_York", Time.zone.tzinfo.name
+    assert_equal "America/New_York", Time.zone.name
     assert_equal(-18_000, Time.zone.utc_offset)
   end
 
   def test_time_zone_setter_with_invalid_zone
-    assert_raise(ArgumentError){ Time.zone = "No such timezone exists" }
-    assert_raise(ArgumentError){ Time.zone = -15.hours }
-    assert_raise(ArgumentError){ Time.zone = Object.new }
+    assert_raise(ArgumentError) { Time.zone = "No such timezone exists" }
+    assert_raise(ArgumentError) { Time.zone = -15.hours }
+    assert_raise(ArgumentError) { Time.zone = Object.new }
   end
 
   def test_find_zone_without_bang_returns_nil_if_time_zone_can_not_be_found
-    assert_nil Time.find_zone('No such timezone exists')
+    assert_nil Time.find_zone("No such timezone exists")
     assert_nil Time.find_zone(-15.hours)
     assert_nil Time.find_zone(Object.new)
   end
 
   def test_find_zone_with_bang_raises_if_time_zone_can_not_be_found
-    assert_raise(ArgumentError) { Time.find_zone!('No such timezone exists') }
+    assert_raise(ArgumentError) { Time.find_zone!("No such timezone exists") }
     assert_raise(ArgumentError) { Time.find_zone!(-15.hours) }
     assert_raise(ArgumentError) { Time.find_zone!(Object.new) }
   end
 
   def test_time_zone_setter_with_find_zone_without_bang
-    assert_nil Time.zone = Time.find_zone('No such timezone exists')
+    assert_nil Time.zone = Time.find_zone("No such timezone exists")
     assert_nil Time.zone = Time.find_zone(-15.hours)
     assert_nil Time.zone = Time.find_zone(Object.new)
   end
 
   def test_current_returns_time_now_when_zone_not_set
-    with_env_tz 'US/Eastern' do
+    with_env_tz "US/Eastern" do
       Time.stub(:now, Time.local(2000)) do
         assert_equal false, Time.current.is_a?(ActiveSupport::TimeWithZone)
         assert_equal Time.local(2000), Time.current
@@ -1073,22 +1183,22 @@ class TimeWithZoneMethodsForTimeAndDateTimeTest < ActiveSupport::TestCase
   end
 
   def test_current_returns_time_zone_now_when_zone_set
-    Time.zone = ActiveSupport::TimeZone['Eastern Time (US & Canada)']
-    with_env_tz 'US/Eastern' do
+    Time.zone = ActiveSupport::TimeZone["Eastern Time (US & Canada)"]
+    with_env_tz "US/Eastern" do
       Time.stub(:now, Time.local(2000)) do
         assert_equal true, Time.current.is_a?(ActiveSupport::TimeWithZone)
-        assert_equal 'Eastern Time (US & Canada)', Time.current.time_zone.name
+        assert_equal "Eastern Time (US & Canada)", Time.current.time_zone.name
         assert_equal Time.utc(2000), Time.current.time
       end
     end
   end
 
   def test_time_in_time_zone_doesnt_affect_receiver
-    with_env_tz 'Europe/London' do
+    with_env_tz "Europe/London" do
       time = Time.local(2000, 7, 1)
-      time_with_zone = time.in_time_zone('Eastern Time (US & Canada)')
+      time_with_zone = time.in_time_zone("Eastern Time (US & Canada)")
       assert_equal Time.utc(2000, 6, 30, 23, 0, 0), time_with_zone
-      assert_not time.utc?, 'time expected to be local, but is UTC'
+      assert_not time.utc?, "time expected to be local, but is UTC"
     end
   end
 end
@@ -1101,11 +1211,11 @@ class TimeWithZoneMethodsForDate < ActiveSupport::TestCase
   end
 
   def test_in_time_zone
-    with_tz_default 'Alaska' do
-      assert_equal 'Sat, 01 Jan 2000 00:00:00 AKST -09:00', @d.in_time_zone.inspect
+    with_tz_default "Alaska" do
+      assert_equal "Sat, 01 Jan 2000 00:00:00 AKST -09:00", @d.in_time_zone.inspect
     end
-    with_tz_default 'Hawaii' do
-      assert_equal 'Sat, 01 Jan 2000 00:00:00 HST -10:00', @d.in_time_zone.inspect
+    with_tz_default "Hawaii" do
+      assert_equal "Sat, 01 Jan 2000 00:00:00 HST -10:00", @d.in_time_zone.inspect
     end
     with_tz_default nil do
       assert_equal @d.to_time, @d.in_time_zone
@@ -1114,16 +1224,16 @@ class TimeWithZoneMethodsForDate < ActiveSupport::TestCase
 
   def test_nil_time_zone
     with_tz_default nil do
-      assert !@d.in_time_zone.respond_to?(:period), 'no period method'
+      assert !@d.in_time_zone.respond_to?(:period), "no period method"
     end
   end
 
   def test_in_time_zone_with_argument
-    with_tz_default 'Eastern Time (US & Canada)' do # Time.zone will not affect #in_time_zone(zone)
-      assert_equal 'Sat, 01 Jan 2000 00:00:00 AKST -09:00', @d.in_time_zone('Alaska').inspect
-      assert_equal 'Sat, 01 Jan 2000 00:00:00 HST -10:00', @d.in_time_zone('Hawaii').inspect
-      assert_equal 'Sat, 01 Jan 2000 00:00:00 UTC +00:00', @d.in_time_zone('UTC').inspect
-      assert_equal 'Sat, 01 Jan 2000 00:00:00 AKST -09:00', @d.in_time_zone(-9.hours).inspect
+    with_tz_default "Eastern Time (US & Canada)" do # Time.zone will not affect #in_time_zone(zone)
+      assert_equal "Sat, 01 Jan 2000 00:00:00 AKST -09:00", @d.in_time_zone("Alaska").inspect
+      assert_equal "Sat, 01 Jan 2000 00:00:00 HST -10:00", @d.in_time_zone("Hawaii").inspect
+      assert_equal "Sat, 01 Jan 2000 00:00:00 UTC +00:00", @d.in_time_zone("UTC").inspect
+      assert_equal "Sat, 01 Jan 2000 00:00:00 AKST -09:00", @d.in_time_zone(-9.hours).inspect
     end
   end
 
@@ -1144,15 +1254,15 @@ class TimeWithZoneMethodsForString < ActiveSupport::TestCase
   end
 
   def test_in_time_zone
-    with_tz_default 'Alaska' do
-      assert_equal 'Sat, 01 Jan 2000 00:00:00 AKST -09:00', @s.in_time_zone.inspect
-      assert_equal 'Fri, 31 Dec 1999 15:00:00 AKST -09:00', @u.in_time_zone.inspect
-      assert_equal 'Fri, 31 Dec 1999 15:00:00 AKST -09:00', @z.in_time_zone.inspect
+    with_tz_default "Alaska" do
+      assert_equal "Sat, 01 Jan 2000 00:00:00 AKST -09:00", @s.in_time_zone.inspect
+      assert_equal "Fri, 31 Dec 1999 15:00:00 AKST -09:00", @u.in_time_zone.inspect
+      assert_equal "Fri, 31 Dec 1999 15:00:00 AKST -09:00", @z.in_time_zone.inspect
     end
-    with_tz_default 'Hawaii' do
-      assert_equal 'Sat, 01 Jan 2000 00:00:00 HST -10:00', @s.in_time_zone.inspect
-      assert_equal 'Fri, 31 Dec 1999 14:00:00 HST -10:00', @u.in_time_zone.inspect
-      assert_equal 'Fri, 31 Dec 1999 14:00:00 HST -10:00', @z.in_time_zone.inspect
+    with_tz_default "Hawaii" do
+      assert_equal "Sat, 01 Jan 2000 00:00:00 HST -10:00", @s.in_time_zone.inspect
+      assert_equal "Fri, 31 Dec 1999 14:00:00 HST -10:00", @u.in_time_zone.inspect
+      assert_equal "Fri, 31 Dec 1999 14:00:00 HST -10:00", @z.in_time_zone.inspect
     end
     with_tz_default nil do
       assert_equal @s.to_time, @s.in_time_zone
@@ -1163,26 +1273,26 @@ class TimeWithZoneMethodsForString < ActiveSupport::TestCase
 
   def test_nil_time_zone
     with_tz_default nil do
-      assert !@s.in_time_zone.respond_to?(:period), 'no period method'
-      assert !@u.in_time_zone.respond_to?(:period), 'no period method'
-      assert !@z.in_time_zone.respond_to?(:period), 'no period method'
+      assert !@s.in_time_zone.respond_to?(:period), "no period method"
+      assert !@u.in_time_zone.respond_to?(:period), "no period method"
+      assert !@z.in_time_zone.respond_to?(:period), "no period method"
     end
   end
 
   def test_in_time_zone_with_argument
-    with_tz_default 'Eastern Time (US & Canada)' do # Time.zone will not affect #in_time_zone(zone)
-      assert_equal 'Sat, 01 Jan 2000 00:00:00 AKST -09:00', @s.in_time_zone('Alaska').inspect
-      assert_equal 'Fri, 31 Dec 1999 15:00:00 AKST -09:00', @u.in_time_zone('Alaska').inspect
-      assert_equal 'Fri, 31 Dec 1999 15:00:00 AKST -09:00', @z.in_time_zone('Alaska').inspect
-      assert_equal 'Sat, 01 Jan 2000 00:00:00 HST -10:00', @s.in_time_zone('Hawaii').inspect
-      assert_equal 'Fri, 31 Dec 1999 14:00:00 HST -10:00', @u.in_time_zone('Hawaii').inspect
-      assert_equal 'Fri, 31 Dec 1999 14:00:00 HST -10:00', @z.in_time_zone('Hawaii').inspect
-      assert_equal 'Sat, 01 Jan 2000 00:00:00 UTC +00:00', @s.in_time_zone('UTC').inspect
-      assert_equal 'Sat, 01 Jan 2000 00:00:00 UTC +00:00', @u.in_time_zone('UTC').inspect
-      assert_equal 'Sat, 01 Jan 2000 00:00:00 UTC +00:00', @z.in_time_zone('UTC').inspect
-      assert_equal 'Sat, 01 Jan 2000 00:00:00 AKST -09:00', @s.in_time_zone(-9.hours).inspect
-      assert_equal 'Fri, 31 Dec 1999 15:00:00 AKST -09:00', @u.in_time_zone(-9.hours).inspect
-      assert_equal 'Fri, 31 Dec 1999 15:00:00 AKST -09:00', @z.in_time_zone(-9.hours).inspect
+    with_tz_default "Eastern Time (US & Canada)" do # Time.zone will not affect #in_time_zone(zone)
+      assert_equal "Sat, 01 Jan 2000 00:00:00 AKST -09:00", @s.in_time_zone("Alaska").inspect
+      assert_equal "Fri, 31 Dec 1999 15:00:00 AKST -09:00", @u.in_time_zone("Alaska").inspect
+      assert_equal "Fri, 31 Dec 1999 15:00:00 AKST -09:00", @z.in_time_zone("Alaska").inspect
+      assert_equal "Sat, 01 Jan 2000 00:00:00 HST -10:00", @s.in_time_zone("Hawaii").inspect
+      assert_equal "Fri, 31 Dec 1999 14:00:00 HST -10:00", @u.in_time_zone("Hawaii").inspect
+      assert_equal "Fri, 31 Dec 1999 14:00:00 HST -10:00", @z.in_time_zone("Hawaii").inspect
+      assert_equal "Sat, 01 Jan 2000 00:00:00 UTC +00:00", @s.in_time_zone("UTC").inspect
+      assert_equal "Sat, 01 Jan 2000 00:00:00 UTC +00:00", @u.in_time_zone("UTC").inspect
+      assert_equal "Sat, 01 Jan 2000 00:00:00 UTC +00:00", @z.in_time_zone("UTC").inspect
+      assert_equal "Sat, 01 Jan 2000 00:00:00 AKST -09:00", @s.in_time_zone(-9.hours).inspect
+      assert_equal "Fri, 31 Dec 1999 15:00:00 AKST -09:00", @u.in_time_zone(-9.hours).inspect
+      assert_equal "Fri, 31 Dec 1999 15:00:00 AKST -09:00", @z.in_time_zone(-9.hours).inspect
     end
   end
 
@@ -1197,4 +1307,10 @@ class TimeWithZoneMethodsForString < ActiveSupport::TestCase
     assert_raise(ArgumentError) { @u.in_time_zone(Object.new) }
     assert_raise(ArgumentError) { @z.in_time_zone(Object.new) }
   end
+
+  def test_in_time_zone_with_ambiguous_time
+    with_tz_default "Moscow" do
+      assert_equal Time.utc(2014, 10, 25, 22, 0, 0), "2014-10-26 01:00:00".in_time_zone
+    end
+  end
 end
diff --git a/activesupport/test/core_ext/uri_ext_test.rb b/activesupport/test/core_ext/uri_ext_test.rb
index 1694fe7e72..8816b0d392 100644
--- a/activesupport/test/core_ext/uri_ext_test.rb
+++ b/activesupport/test/core_ext/uri_ext_test.rb
@@ -1,6 +1,8 @@
-require 'abstract_unit'
-require 'uri'
-require 'active_support/core_ext/uri'
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "uri"
+require "active_support/core_ext/uri"
 
 class URIExtTest < ActiveSupport::TestCase
   def test_uri_decode_handle_multibyte
diff --git a/activesupport/test/current_attributes_test.rb b/activesupport/test/current_attributes_test.rb
new file mode 100644
index 0000000000..1669f08f68
--- /dev/null
+++ b/activesupport/test/current_attributes_test.rb
@@ -0,0 +1,105 @@
+# frozen_string_literal: true
+
+require "abstract_unit"
+
+class CurrentAttributesTest < ActiveSupport::TestCase
+  Person = Struct.new(:name, :time_zone)
+
+  class Current < ActiveSupport::CurrentAttributes
+    attribute :world, :account, :person, :request
+    delegate :time_zone, to: :person
+
+    resets { Time.zone = "UTC" }
+
+    def account=(account)
+      super
+      self.person = "#{account}'s person"
+    end
+
+    def person=(person)
+      super
+      Time.zone = person.try(:time_zone)
+    end
+
+    def request
+      "#{super} something"
+    end
+
+    def intro
+      "#{person.name}, in #{time_zone}"
+    end
+  end
+
+  setup do
+    @original_time_zone = Time.zone
+    Current.reset
+  end
+
+  teardown do
+    Time.zone = @original_time_zone
+  end
+
+  test "read and write attribute" do
+    Current.world = "world/1"
+    assert_equal "world/1", Current.world
+  end
+
+  test "read overwritten attribute method" do
+    Current.request = "request/1"
+    assert_equal "request/1 something", Current.request
+  end
+
+  test "set attribute via overwritten method" do
+    Current.account = "account/1"
+    assert_equal "account/1", Current.account
+    assert_equal "account/1's person", Current.person
+  end
+
+  test "set auxiliary class via overwritten method" do
+    Current.person = Person.new("David", "Central Time (US & Canada)")
+    assert_equal "Central Time (US & Canada)", Time.zone.name
+  end
+
+  test "resets auxiliary class via callback" do
+    Current.person = Person.new("David", "Central Time (US & Canada)")
+    assert_equal "Central Time (US & Canada)", Time.zone.name
+
+    Current.reset
+    assert_equal "UTC", Time.zone.name
+  end
+
+  test "set attribute only via scope" do
+    Current.world = "world/1"
+
+    Current.set(world: "world/2") do
+      assert_equal "world/2", Current.world
+    end
+
+    assert_equal "world/1", Current.world
+  end
+
+  test "set multiple attributes" do
+    Current.world = "world/1"
+    Current.account = "account/1"
+
+    Current.set(world: "world/2", account: "account/2") do
+      assert_equal "world/2", Current.world
+      assert_equal "account/2", Current.account
+    end
+
+    assert_equal "world/1", Current.world
+    assert_equal "account/1", Current.account
+  end
+
+  test "delegation" do
+    Current.person = Person.new("David", "Central Time (US & Canada)")
+    assert_equal "Central Time (US & Canada)", Current.time_zone
+    assert_equal "Central Time (US & Canada)", Current.instance.time_zone
+  end
+
+  test "all methods forward to the instance" do
+    Current.person = Person.new("David", "Central Time (US & Canada)")
+    assert_equal "David, in Central Time (US & Canada)", Current.intro
+    assert_equal "David, in Central Time (US & Canada)", Current.instance.intro
+  end
+end
diff --git a/activesupport/test/dependencies/check_warnings.rb b/activesupport/test/dependencies/check_warnings.rb
index 03c3dca1d6..f7d7d2dbc7 100644
--- a/activesupport/test/dependencies/check_warnings.rb
+++ b/activesupport/test/dependencies/check_warnings.rb
@@ -1,2 +1,4 @@
+# frozen_string_literal: true
+
 $check_warnings_load_count += 1
 $checked_verbose = $VERBOSE
diff --git a/activesupport/test/dependencies/conflict.rb b/activesupport/test/dependencies/conflict.rb
index e888b7b54c..aa22ec0b09 100644
--- a/activesupport/test/dependencies/conflict.rb
+++ b/activesupport/test/dependencies/conflict.rb
@@ -1 +1,3 @@
-Conflict = 1
\ No newline at end of file
+# frozen_string_literal: true
+
+Conflict = 1
diff --git a/activesupport/test/dependencies/cross_site_depender.rb b/activesupport/test/dependencies/cross_site_depender.rb
index a31015fc5e..3ddea7fc4b 100644
--- a/activesupport/test/dependencies/cross_site_depender.rb
+++ b/activesupport/test/dependencies/cross_site_depender.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class CrossSiteDepender
   CrossSiteDependency
-end
\ No newline at end of file
+end
diff --git a/activesupport/test/dependencies/mutual_one.rb b/activesupport/test/dependencies/mutual_one.rb
index 576eb31711..bb48fddd4d 100644
--- a/activesupport/test/dependencies/mutual_one.rb
+++ b/activesupport/test/dependencies/mutual_one.rb
@@ -1,4 +1,6 @@
+# frozen_string_literal: true
+
 $mutual_dependencies_count += 1
-require_dependency 'mutual_two'
-require_dependency 'mutual_two.rb'
-require_dependency 'mutual_two'
+require_dependency "mutual_two"
+require_dependency "mutual_two.rb"
+require_dependency "mutual_two"
diff --git a/activesupport/test/dependencies/mutual_two.rb b/activesupport/test/dependencies/mutual_two.rb
index fdbc2dcd84..ed354ed75e 100644
--- a/activesupport/test/dependencies/mutual_two.rb
+++ b/activesupport/test/dependencies/mutual_two.rb
@@ -1,4 +1,6 @@
+# frozen_string_literal: true
+
 $mutual_dependencies_count += 1
-require_dependency 'mutual_one.rb'
-require_dependency 'mutual_one'
-require_dependency 'mutual_one.rb'
+require_dependency "mutual_one.rb"
+require_dependency "mutual_one"
+require_dependency "mutual_one.rb"
diff --git a/activesupport/test/dependencies/raises_exception.rb b/activesupport/test/dependencies/raises_exception.rb
index dd745ac20e..67bfaabb3e 100644
--- a/activesupport/test/dependencies/raises_exception.rb
+++ b/activesupport/test/dependencies/raises_exception.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 $raises_exception_load_count += 1
-raise Exception, 'Loading me failed, so do not add to loaded or history.'
+raise Exception, "Loading me failed, so do not add to loaded or history."
 $raises_exception_load_count += 1
diff --git a/activesupport/test/dependencies/raises_exception_without_blame_file.rb b/activesupport/test/dependencies/raises_exception_without_blame_file.rb
index 4b2da6ff30..3a6533cd3a 100644
--- a/activesupport/test/dependencies/raises_exception_without_blame_file.rb
+++ b/activesupport/test/dependencies/raises_exception_without_blame_file.rb
@@ -1,4 +1,6 @@
-exception = Exception.new('I am not blamable!')
+# frozen_string_literal: true
+
+exception = Exception.new("I am not blamable!")
 class << exception
   undef_method(:blame_file!)
 end
diff --git a/activesupport/test/dependencies/requires_nonexistent0.rb b/activesupport/test/dependencies/requires_nonexistent0.rb
index 7e24b3916c..d09dbd2485 100644
--- a/activesupport/test/dependencies/requires_nonexistent0.rb
+++ b/activesupport/test/dependencies/requires_nonexistent0.rb
@@ -1 +1,3 @@
-require 'RMagickDontExistDude'
+# frozen_string_literal: true
+
+require "RMagickDontExistDude"
diff --git a/activesupport/test/dependencies/requires_nonexistent1.rb b/activesupport/test/dependencies/requires_nonexistent1.rb
index 41e6668164..ce96229172 100644
--- a/activesupport/test/dependencies/requires_nonexistent1.rb
+++ b/activesupport/test/dependencies/requires_nonexistent1.rb
@@ -1 +1,3 @@
-require_dependency 'requires_nonexistent0'
+# frozen_string_literal: true
+
+require_dependency "requires_nonexistent0"
diff --git a/activesupport/test/dependencies/service_one.rb b/activesupport/test/dependencies/service_one.rb
index f43bfea235..2a4a39144d 100644
--- a/activesupport/test/dependencies/service_one.rb
+++ b/activesupport/test/dependencies/service_one.rb
@@ -1,5 +1,7 @@
+# frozen_string_literal: true
+
 $loaded_service_one ||= 0
 $loaded_service_one += 1
 
 class ServiceOne
-end
\ No newline at end of file
+end
diff --git a/activesupport/test/dependencies/service_two.rb b/activesupport/test/dependencies/service_two.rb
index 5205a78bb8..29cd73cbcd 100644
--- a/activesupport/test/dependencies/service_two.rb
+++ b/activesupport/test/dependencies/service_two.rb
@@ -1,2 +1,4 @@
+# frozen_string_literal: true
+
 class ServiceTwo
-end
\ No newline at end of file
+end
diff --git a/activesupport/test/dependencies_test.rb b/activesupport/test/dependencies_test.rb
index 04e7b24d30..d636da46d2 100644
--- a/activesupport/test/dependencies_test.rb
+++ b/activesupport/test/dependencies_test.rb
@@ -1,7 +1,9 @@
-require 'abstract_unit'
-require 'pp'
-require 'active_support/dependencies'
-require 'dependencies_test_helpers'
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "pp"
+require "active_support/dependencies"
+require "dependencies_test_helpers"
 
 module ModuleWithMissing
   mattr_accessor :missing_count
@@ -29,18 +31,18 @@ class DependenciesTest < ActiveSupport::TestCase
 
   def test_depend_on_path
     expected = assert_raises(LoadError) do
-      Kernel.require 'omgwtfbbq'
+      Kernel.require "omgwtfbbq"
     end
 
     e = assert_raises(LoadError) do
-      ActiveSupport::Dependencies.depend_on 'omgwtfbbq'
+      ActiveSupport::Dependencies.depend_on "omgwtfbbq"
     end
     assert_equal expected.path, e.path
   end
 
   def test_require_dependency_accepts_an_object_which_implements_to_path
     o = Object.new
-    def o.to_path; 'dependencies/service_one'; end
+    def o.to_path; "dependencies/service_one"; end
     assert_nothing_raised {
       require_dependency o
     }
@@ -51,8 +53,8 @@ class DependenciesTest < ActiveSupport::TestCase
 
   def test_tracking_loaded_files
     with_loading do
-      require_dependency 'dependencies/service_one'
-      require_dependency 'dependencies/service_two'
+      require_dependency "dependencies/service_one"
+      require_dependency "dependencies/service_two"
       assert_equal 2, ActiveSupport::Dependencies.loaded.size
     end
   ensure
@@ -61,8 +63,8 @@ class DependenciesTest < ActiveSupport::TestCase
 
   def test_tracking_identical_loaded_files
     with_loading do
-      require_dependency 'dependencies/service_one'
-      require_dependency 'dependencies/service_one'
+      require_dependency "dependencies/service_one"
+      require_dependency "dependencies/service_one"
       assert_equal 1, ActiveSupport::Dependencies.loaded.size
     end
   ensure
@@ -75,16 +77,16 @@ class DependenciesTest < ActiveSupport::TestCase
 
   def test_dependency_which_raises_exception_isnt_added_to_loaded_set
     with_loading do
-      filename = 'dependencies/raises_exception'
+      filename = "dependencies/raises_exception"
       expanded = File.expand_path(filename)
       $raises_exception_load_count = 0
 
       5.times do |count|
-        e = assert_raise Exception, 'should have loaded dependencies/raises_exception which raises an exception' do
+        e = assert_raise Exception, "should have loaded dependencies/raises_exception which raises an exception" do
           require_dependency filename
         end
 
-        assert_equal 'Loading me failed, so do not add to loaded or history.', e.message
+        assert_equal "Loading me failed, so do not add to loaded or history.", e.message
         assert_equal count + 1, $raises_exception_load_count
 
         assert_not ActiveSupport::Dependencies.loaded.include?(expanded)
@@ -95,16 +97,16 @@ class DependenciesTest < ActiveSupport::TestCase
 
   def test_dependency_which_raises_doesnt_blindly_call_blame_file!
     with_loading do
-      filename = 'dependencies/raises_exception_without_blame_file'
+      filename = "dependencies/raises_exception_without_blame_file"
       assert_raises(Exception) { require_dependency filename }
     end
   end
 
   def test_warnings_should_be_enabled_on_first_load
-    with_loading 'dependencies' do
+    with_loading "dependencies" do
       old_warnings, ActiveSupport::Dependencies.warnings_on_first_load = ActiveSupport::Dependencies.warnings_on_first_load, true
       filename = "check_warnings"
-      expanded = File.expand_path("#{File.dirname(__FILE__)}/dependencies/#{filename}")
+      expanded = File.expand_path("dependencies/#{filename}", __dir__)
       $check_warnings_load_count = 0
 
       assert_not ActiveSupport::Dependencies.loaded.include?(expanded)
@@ -112,41 +114,41 @@ class DependenciesTest < ActiveSupport::TestCase
 
       silence_warnings { require_dependency filename }
       assert_equal 1, $check_warnings_load_count
-      assert_equal true, $checked_verbose, 'On first load warnings should be enabled.'
+      assert_equal true, $checked_verbose, "On first load warnings should be enabled."
 
-      assert ActiveSupport::Dependencies.loaded.include?(expanded)
+      assert_includes ActiveSupport::Dependencies.loaded, expanded
       ActiveSupport::Dependencies.clear
       assert_not ActiveSupport::Dependencies.loaded.include?(expanded)
-      assert ActiveSupport::Dependencies.history.include?(expanded)
+      assert_includes ActiveSupport::Dependencies.history, expanded
 
       silence_warnings { require_dependency filename }
       assert_equal 2, $check_warnings_load_count
-      assert_equal nil, $checked_verbose, 'After first load warnings should be left alone.'
+      assert_nil $checked_verbose, "After first load warnings should be left alone."
 
-      assert ActiveSupport::Dependencies.loaded.include?(expanded)
+      assert_includes ActiveSupport::Dependencies.loaded, expanded
       ActiveSupport::Dependencies.clear
       assert_not ActiveSupport::Dependencies.loaded.include?(expanded)
-      assert ActiveSupport::Dependencies.history.include?(expanded)
+      assert_includes ActiveSupport::Dependencies.history, expanded
 
       enable_warnings { require_dependency filename }
       assert_equal 3, $check_warnings_load_count
-      assert_equal true, $checked_verbose, 'After first load warnings should be left alone.'
+      assert_equal true, $checked_verbose, "After first load warnings should be left alone."
 
-      assert ActiveSupport::Dependencies.loaded.include?(expanded)
+      assert_includes ActiveSupport::Dependencies.loaded, expanded
       ActiveSupport::Dependencies.warnings_on_first_load = old_warnings
     end
   end
 
   def test_mutual_dependencies_dont_infinite_loop
-    with_loading 'dependencies' do
+    with_loading "dependencies" do
       $mutual_dependencies_count = 0
-      assert_nothing_raised { require_dependency 'mutual_one' }
+      assert_nothing_raised { require_dependency "mutual_one" }
       assert_equal 2, $mutual_dependencies_count
 
       ActiveSupport::Dependencies.clear
 
       $mutual_dependencies_count = 0
-      assert_nothing_raised { require_dependency 'mutual_two' }
+      assert_nothing_raised { require_dependency "mutual_two" }
       assert_equal 2, $mutual_dependencies_count
     end
   end
@@ -167,7 +169,7 @@ class DependenciesTest < ActiveSupport::TestCase
 
   def test_require_dependency_does_not_assume_any_particular_constant_is_defined
     with_autoloading_fixtures do
-      require_dependency 'typo'
+      require_dependency "typo"
       assert_equal 1, TypO
     end
   end
@@ -175,7 +177,7 @@ class DependenciesTest < ActiveSupport::TestCase
   # Regression, see https://github.com/rails/rails/issues/16468.
   def test_require_dependency_interaction_with_autoloading
     with_autoloading_fixtures do
-      require_dependency 'typo'
+      require_dependency "typo"
       assert_equal 1, TypO
 
       e = assert_raise(LoadError) { Typo }
@@ -253,7 +255,7 @@ class DependenciesTest < ActiveSupport::TestCase
     with_autoloading_fixtures do
       assert_kind_of Class, ClassFolder::ClassFolderSubclass
       assert_kind_of Class, ClassFolder
-      assert_equal 'indeed', ClassFolder::ClassFolderSubclass::ConstantInClassFolder
+      assert_equal "indeed", ClassFolder::ClassFolderSubclass::ConstantInClassFolder
     end
   ensure
     remove_constants(:ClassFolder)
@@ -271,7 +273,8 @@ class DependenciesTest < ActiveSupport::TestCase
 
   def test_raising_discards_autoloaded_constants
     with_autoloading_fixtures do
-      assert_raises(Exception, 'arbitray exception message') { RaisesArbitraryException }
+      e = assert_raises(Exception) { RaisesArbitraryException }
+      assert_equal("arbitrary exception message", e.message)
       assert_not defined?(A)
       assert_not defined?(RaisesArbitraryException)
     end
@@ -292,7 +295,7 @@ class DependenciesTest < ActiveSupport::TestCase
   end
 
   def test_doesnt_break_normal_require
-    path = File.expand_path("../autoloading_fixtures/load_path", __FILE__)
+    path = File.expand_path("autoloading_fixtures/load_path", __dir__)
     original_path = $:.dup
     $:.push(path)
     with_autoloading_fixtures do
@@ -311,7 +314,7 @@ class DependenciesTest < ActiveSupport::TestCase
   end
 
   def test_doesnt_break_normal_require_nested
-    path = File.expand_path("../autoloading_fixtures/load_path", __FILE__)
+    path = File.expand_path("autoloading_fixtures/load_path", __dir__)
     original_path = $:.dup
     $:.push(path)
 
@@ -331,12 +334,12 @@ class DependenciesTest < ActiveSupport::TestCase
   end
 
   def test_require_returns_true_when_file_not_yet_required
-    path = File.expand_path("../autoloading_fixtures/load_path", __FILE__)
+    path = File.expand_path("autoloading_fixtures/load_path", __dir__)
     original_path = $:.dup
     $:.push(path)
 
     with_loading do
-      assert_equal true, require('loaded_constant')
+      assert_equal true, require("loaded_constant")
     end
   ensure
     remove_constants(:LoadedConstant)
@@ -344,13 +347,13 @@ class DependenciesTest < ActiveSupport::TestCase
   end
 
   def test_require_returns_true_when_file_not_yet_required_even_when_no_new_constants_added
-    path = File.expand_path("../autoloading_fixtures/load_path", __FILE__)
+    path = File.expand_path("autoloading_fixtures/load_path", __dir__)
     original_path = $:.dup
     $:.push(path)
 
     with_loading do
       Object.module_eval "module LoadedConstant; end"
-      assert_equal true, require('loaded_constant')
+      assert_equal true, require("loaded_constant")
     end
   ensure
     remove_constants(:LoadedConstant)
@@ -358,13 +361,13 @@ class DependenciesTest < ActiveSupport::TestCase
   end
 
   def test_require_returns_false_when_file_already_required
-    path = File.expand_path("../autoloading_fixtures/load_path", __FILE__)
+    path = File.expand_path("autoloading_fixtures/load_path", __dir__)
     original_path = $:.dup
     $:.push(path)
 
     with_loading do
-      require 'loaded_constant'
-      assert_equal false, require('loaded_constant')
+      require "loaded_constant"
+      assert_equal false, require("loaded_constant")
     end
   ensure
     remove_constants(:LoadedConstant)
@@ -373,18 +376,18 @@ class DependenciesTest < ActiveSupport::TestCase
 
   def test_require_raises_load_error_when_file_not_found
     with_loading do
-      assert_raise(LoadError) { require 'this_file_dont_exist_dude' }
+      assert_raise(LoadError) { require "this_file_dont_exist_dude" }
     end
   end
 
   def test_load_returns_true_when_file_found
-    path = File.expand_path("../autoloading_fixtures/load_path", __FILE__)
+    path = File.expand_path("autoloading_fixtures/load_path", __dir__)
     original_path = $:.dup
     $:.push(path)
 
     with_loading do
-      assert_equal true, load('loaded_constant.rb')
-      assert_equal true, load('loaded_constant.rb')
+      assert_equal true, load("loaded_constant.rb")
+      assert_equal true, load("loaded_constant.rb")
     end
   ensure
     remove_constants(:LoadedConstant)
@@ -393,18 +396,21 @@ class DependenciesTest < ActiveSupport::TestCase
 
   def test_load_raises_load_error_when_file_not_found
     with_loading do
-      assert_raise(LoadError) { load 'this_file_dont_exist_dude.rb' }
+      assert_raise(LoadError) { load "this_file_dont_exist_dude.rb" }
     end
   end
 
-  def failing_test_access_thru_and_upwards_fails
-    with_autoloading_fixtures do
-      assert_not defined?(ModuleFolder)
-      assert_raise(NameError) { ModuleFolder::Object }
-      assert_raise(NameError) { ModuleFolder::NestedClass::Object }
+  # This raises only on 2.5.. (warns on ..2.4)
+  if RUBY_VERSION > "2.5"
+    def test_access_thru_and_upwards_fails
+      with_autoloading_fixtures do
+        assert_not defined?(ModuleFolder)
+        assert_raise(NameError) { ModuleFolder::Object }
+        assert_raise(NameError) { ModuleFolder::NestedClass::Object }
+      end
+    ensure
+      remove_constants(:ModuleFolder)
     end
-  ensure
-    remove_constants(:ModuleFolder)
   end
 
   def test_non_existing_const_raises_name_error_with_fully_qualified_name
@@ -429,38 +435,38 @@ class DependenciesTest < ActiveSupport::TestCase
   end
 
   def test_loadable_constants_for_path_should_handle_empty_autoloads
-    assert_equal [], ActiveSupport::Dependencies.loadable_constants_for_path('hello')
+    assert_equal [], ActiveSupport::Dependencies.loadable_constants_for_path("hello")
   end
 
   def test_loadable_constants_for_path_should_handle_relative_paths
-    fake_root = 'dependencies'
-    relative_root = File.dirname(__FILE__) + '/dependencies'
-    ['', '/'].each do |suffix|
+    fake_root = "dependencies"
+    relative_root = File.expand_path("dependencies", __dir__)
+    ["", "/"].each do |suffix|
       with_loading fake_root + suffix do
-        assert_equal ["A::B"], ActiveSupport::Dependencies.loadable_constants_for_path(relative_root + '/a/b')
+        assert_equal ["A::B"], ActiveSupport::Dependencies.loadable_constants_for_path(relative_root + "/a/b")
       end
     end
   end
 
   def test_loadable_constants_for_path_should_provide_all_results
-    fake_root = '/usr/apps/backpack'
-    with_loading fake_root, fake_root + '/lib' do
+    fake_root = "/usr/apps/backpack"
+    with_loading fake_root, fake_root + "/lib" do
       root = ActiveSupport::Dependencies.autoload_paths.first
-      assert_equal ["Lib::A::B", "A::B"], ActiveSupport::Dependencies.loadable_constants_for_path(root + '/lib/a/b')
+      assert_equal ["Lib::A::B", "A::B"], ActiveSupport::Dependencies.loadable_constants_for_path(root + "/lib/a/b")
     end
   end
 
   def test_loadable_constants_for_path_should_uniq_results
-    fake_root = '/usr/apps/backpack/lib'
-    with_loading fake_root, fake_root + '/' do
+    fake_root = "/usr/apps/backpack/lib"
+    with_loading fake_root, fake_root + "/" do
       root = ActiveSupport::Dependencies.autoload_paths.first
-      assert_equal ["A::B"], ActiveSupport::Dependencies.loadable_constants_for_path(root + '/a/b')
+      assert_equal ["A::B"], ActiveSupport::Dependencies.loadable_constants_for_path(root + "/a/b")
     end
   end
 
   def test_loadable_constants_with_load_path_without_trailing_slash
-    path = File.dirname(__FILE__) + '/autoloading_fixtures/class_folder/inline_class.rb'
-    with_loading 'autoloading_fixtures/class/' do
+    path = File.expand_path("autoloading_fixtures/class_folder/inline_class.rb", __dir__)
+    with_loading "autoloading_fixtures/class/" do
       assert_equal [], ActiveSupport::Dependencies.loadable_constants_for_path(path)
     end
   end
@@ -524,31 +530,30 @@ class DependenciesTest < ActiveSupport::TestCase
   end
 
   def test_file_search
-    with_loading 'dependencies' do
+    with_loading "dependencies" do
       root = ActiveSupport::Dependencies.autoload_paths.first
-      assert_equal nil, ActiveSupport::Dependencies.search_for_file('service_three')
-      assert_equal nil, ActiveSupport::Dependencies.search_for_file('service_three.rb')
-      assert_equal root + '/service_one.rb', ActiveSupport::Dependencies.search_for_file('service_one')
-      assert_equal root + '/service_one.rb', ActiveSupport::Dependencies.search_for_file('service_one.rb')
+      assert_nil ActiveSupport::Dependencies.search_for_file("service_three")
+      assert_nil ActiveSupport::Dependencies.search_for_file("service_three.rb")
+      assert_equal root + "/service_one.rb", ActiveSupport::Dependencies.search_for_file("service_one")
+      assert_equal root + "/service_one.rb", ActiveSupport::Dependencies.search_for_file("service_one.rb")
     end
   end
 
   def test_file_search_uses_first_in_load_path
-    with_loading 'dependencies', 'autoloading_fixtures' do
+    with_loading "dependencies", "autoloading_fixtures" do
       deps, autoload = ActiveSupport::Dependencies.autoload_paths
       assert_match %r/dependencies/, deps
       assert_match %r/autoloading_fixtures/, autoload
 
-      assert_equal deps + '/conflict.rb', ActiveSupport::Dependencies.search_for_file('conflict')
+      assert_equal deps + "/conflict.rb", ActiveSupport::Dependencies.search_for_file("conflict")
     end
-    with_loading 'autoloading_fixtures', 'dependencies' do
+    with_loading "autoloading_fixtures", "dependencies" do
       autoload, deps = ActiveSupport::Dependencies.autoload_paths
       assert_match %r/dependencies/, deps
       assert_match %r/autoloading_fixtures/, autoload
 
-      assert_equal autoload + '/conflict.rb', ActiveSupport::Dependencies.search_for_file('conflict')
+      assert_equal autoload + "/conflict.rb", ActiveSupport::Dependencies.search_for_file("conflict")
     end
-
   end
 
   def test_custom_const_missing_should_work
@@ -584,11 +589,11 @@ class DependenciesTest < ActiveSupport::TestCase
 
   def test_const_missing_in_anonymous_modules_raises_if_the_constant_belongs_to_Object
     with_autoloading_fixtures do
-      require_dependency 'em'
+      require_dependency "em"
 
       mod = Module.new
       e = assert_raise(NameError) { mod::EM }
-      assert_equal 'EM cannot be autoloaded from an anonymous class or module', e.message
+      assert_equal "EM cannot be autoloaded from an anonymous class or module", e.message
       assert_equal :EM, e.name
     end
   ensure
@@ -596,7 +601,7 @@ class DependenciesTest < ActiveSupport::TestCase
   end
 
   def test_removal_from_tree_should_be_detected
-    with_loading 'dependencies' do
+    with_loading "dependencies" do
       c = ServiceOne
       ActiveSupport::Dependencies.clear
       assert_not defined?(ServiceOne)
@@ -610,7 +615,7 @@ class DependenciesTest < ActiveSupport::TestCase
   end
 
   def test_references_should_work
-    with_loading 'dependencies' do
+    with_loading "dependencies" do
       c = ActiveSupport::Dependencies.reference("ServiceOne")
       service_one_first = ServiceOne
       assert_equal service_one_first, c.get("ServiceOne")
@@ -625,7 +630,7 @@ class DependenciesTest < ActiveSupport::TestCase
   end
 
   def test_constantize_shortcut_for_cached_constant_lookups
-    with_loading 'dependencies' do
+    with_loading "dependencies" do
       assert_equal ServiceOne, ActiveSupport::Dependencies.constantize("ServiceOne")
     end
   ensure
@@ -633,7 +638,7 @@ class DependenciesTest < ActiveSupport::TestCase
   end
 
   def test_nested_load_error_isnt_rescued
-    with_loading 'dependencies' do
+    with_loading "dependencies" do
       assert_raise(LoadError) do
         RequiresNonexistent1
       end
@@ -659,7 +664,7 @@ class DependenciesTest < ActiveSupport::TestCase
 
   def test_autoload_once_pathnames_do_not_add_to_autoloaded_constants
     with_autoloading_fixtures do
-      pathnames = ActiveSupport::Dependencies.autoload_paths.collect{|p| Pathname.new(p)}
+      pathnames = ActiveSupport::Dependencies.autoload_paths.collect { |p| Pathname.new(p) }
       ActiveSupport::Dependencies.autoload_paths = pathnames
       ActiveSupport::Dependencies.autoload_once_paths = pathnames
 
@@ -677,7 +682,7 @@ class DependenciesTest < ActiveSupport::TestCase
 
   def test_application_should_special_case_application_controller
     with_autoloading_fixtures do
-      require_dependency 'application'
+      require_dependency "application"
       assert_equal 10, ApplicationController
       assert ActiveSupport::Dependencies.autoloaded?(:ApplicationController)
     end
@@ -687,14 +692,14 @@ class DependenciesTest < ActiveSupport::TestCase
 
   def test_preexisting_constants_are_not_marked_as_autoloaded
     with_autoloading_fixtures do
-      require_dependency 'em'
+      require_dependency "em"
       assert ActiveSupport::Dependencies.autoloaded?(:EM)
       ActiveSupport::Dependencies.clear
     end
 
     Object.const_set :EM, Class.new
     with_autoloading_fixtures do
-      require_dependency 'em'
+      require_dependency "em"
       assert ! ActiveSupport::Dependencies.autoloaded?(:EM), "EM shouldn't be marked autoloaded!"
       ActiveSupport::Dependencies.clear
     end
@@ -756,15 +761,15 @@ class DependenciesTest < ActiveSupport::TestCase
   end
 
   def test_new_contants_in_without_constants
-    assert_equal [], (ActiveSupport::Dependencies.new_constants_in(Object) { })
-    assert ActiveSupport::Dependencies.constant_watch_stack.all? {|k,v| v.empty? }
+    assert_equal [], (ActiveSupport::Dependencies.new_constants_in(Object) {})
+    assert ActiveSupport::Dependencies.constant_watch_stack.all? { |k, v| v.empty? }
   end
 
   def test_new_constants_in_with_a_single_constant
     assert_equal ["Hello"], ActiveSupport::Dependencies.new_constants_in(Object) {
                               Object.const_set :Hello, 10
                             }.map(&:to_s)
-    assert ActiveSupport::Dependencies.constant_watch_stack.all? {|k,v| v.empty? }
+    assert ActiveSupport::Dependencies.constant_watch_stack.all? { |k, v| v.empty? }
   ensure
     remove_constants(:Hello)
   end
@@ -781,7 +786,7 @@ class DependenciesTest < ActiveSupport::TestCase
     end
 
     assert_equal ["OuterAfter", "OuterBefore"], outer.sort.map(&:to_s)
-    assert ActiveSupport::Dependencies.constant_watch_stack.all? {|k,v| v.empty? }
+    assert ActiveSupport::Dependencies.constant_watch_stack.all? { |k, v| v.empty? }
   ensure
     remove_constants(:OuterBefore, :Inner, :OuterAfter)
   end
@@ -800,7 +805,7 @@ class DependenciesTest < ActiveSupport::TestCase
       M.const_set :OuterAfter, 30
     end
     assert_equal ["M::OuterAfter", "M::OuterBefore"], outer.sort
-    assert ActiveSupport::Dependencies.constant_watch_stack.all? {|k,v| v.empty? }
+    assert ActiveSupport::Dependencies.constant_watch_stack.all? { |k, v| v.empty? }
   ensure
     remove_constants(:M)
   end
@@ -818,7 +823,7 @@ class DependenciesTest < ActiveSupport::TestCase
       M.const_set :OuterAfter, 30
     end
     assert_equal ["M::OuterAfter", "M::OuterBefore"], outer.sort
-    assert ActiveSupport::Dependencies.constant_watch_stack.all? {|k,v| v.empty? }
+    assert ActiveSupport::Dependencies.constant_watch_stack.all? { |k, v| v.empty? }
   ensure
     remove_constants(:M)
   end
@@ -841,7 +846,7 @@ class DependenciesTest < ActiveSupport::TestCase
       assert_not defined?(MultipleConstantFile)
       assert_not defined?(SiblingConstant)
 
-      require_dependency 'multiple_constant_file'
+      require_dependency "multiple_constant_file"
       assert defined?(MultipleConstantFile)
       assert defined?(SiblingConstant)
       assert ActiveSupport::Dependencies.autoloaded?(:MultipleConstantFile)
@@ -881,7 +886,7 @@ class DependenciesTest < ActiveSupport::TestCase
       assert_not defined?(ClassFolder::NestedClass)
       assert_not defined?(ClassFolder::SiblingClass)
 
-      require_dependency 'class_folder/nested_class'
+      require_dependency "class_folder/nested_class"
 
       assert defined?(ClassFolder::NestedClass)
       assert defined?(ClassFolder::SiblingClass)
@@ -959,7 +964,7 @@ class DependenciesTest < ActiveSupport::TestCase
         e = assert_raise NameError do
           ::RaisesNameError::FooBarBaz.object_id
         end
-        assert_equal 'uninitialized constant RaisesNameError::FooBarBaz', e.message
+        assert_equal "uninitialized constant RaisesNameError::FooBarBaz", e.message
         assert !defined?(::RaisesNameError), "::RaisesNameError is defined but it should have failed!"
       end
 
@@ -974,8 +979,8 @@ class DependenciesTest < ActiveSupport::TestCase
   end
 
   def test_remove_constant_handles_double_colon_at_start
-    Object.const_set 'DeleteMe', Module.new
-    DeleteMe.const_set 'OrMe', Module.new
+    Object.const_set "DeleteMe", Module.new
+    DeleteMe.const_set "OrMe", Module.new
     ActiveSupport::Dependencies.remove_constant "::DeleteMe::OrMe"
     assert_not defined?(DeleteMe::OrMe)
     assert defined?(DeleteMe)
@@ -986,9 +991,9 @@ class DependenciesTest < ActiveSupport::TestCase
   end
 
   def test_remove_constant_does_not_trigger_loading_autoloads
-    constant = 'ShouldNotBeAutoloaded'
+    constant = "ShouldNotBeAutoloaded"
     Object.class_eval do
-      autoload constant, File.expand_path('../autoloading_fixtures/should_not_be_required', __FILE__)
+      autoload constant, File.expand_path("autoloading_fixtures/should_not_be_required", __dir__)
     end
 
     assert_nil ActiveSupport::Dependencies.remove_constant(constant), "Kernel#autoload has been triggered by remove_constant"
@@ -1001,8 +1006,8 @@ class DependenciesTest < ActiveSupport::TestCase
     with_autoloading_fixtures do
       _ = ::A    # assignment to silence parse-time warning "possibly useless use of :: in void context"
       _ = ::A::B # assignment to silence parse-time warning "possibly useless use of :: in void context"
-      ActiveSupport::Dependencies.remove_constant('A')
-      ActiveSupport::Dependencies.remove_constant('A::B')
+      ActiveSupport::Dependencies.remove_constant("A")
+      ActiveSupport::Dependencies.remove_constant("A::B")
       assert_not defined?(A)
     end
   ensure
@@ -1036,10 +1041,9 @@ class DependenciesTest < ActiveSupport::TestCase
     remove_constants(:A)
   end
 
-
   def test_autoload_once_paths_should_behave_when_recursively_loading
     old_path = ActiveSupport::Dependencies.autoload_once_paths
-    with_loading 'dependencies', 'autoloading_fixtures' do
+    with_loading "dependencies", "autoloading_fixtures" do
       ActiveSupport::Dependencies.autoload_once_paths = [ActiveSupport::Dependencies.autoload_paths.last]
       assert_not defined?(CrossSiteDependency)
       assert_nothing_raised { CrossSiteDepender.nil? }
@@ -1060,13 +1064,13 @@ class DependenciesTest < ActiveSupport::TestCase
   end
 
   def test_load_and_require_stay_private
-    assert Object.private_methods.include?(:load)
-    assert Object.private_methods.include?(:require)
+    assert_includes Object.private_methods, :load
+    assert_includes Object.private_methods, :require
 
     ActiveSupport::Dependencies.unhook!
 
-    assert Object.private_methods.include?(:load)
-    assert Object.private_methods.include?(:require)
+    assert_includes Object.private_methods, :load
+    assert_includes Object.private_methods, :require
   ensure
     ActiveSupport::Dependencies.hook!
   end
diff --git a/activesupport/test/dependencies_test_helpers.rb b/activesupport/test/dependencies_test_helpers.rb
index e4d5197112..b54a7e70c8 100644
--- a/activesupport/test/dependencies_test_helpers.rb
+++ b/activesupport/test/dependencies_test_helpers.rb
@@ -1,7 +1,9 @@
+# frozen_string_literal: true
+
 module DependenciesTestHelpers
   def with_loading(*from)
     old_mechanism, ActiveSupport::Dependencies.mechanism = ActiveSupport::Dependencies.mechanism, :load
-    this_dir = File.dirname(__FILE__)
+    this_dir = __dir__
     parent_dir = File.dirname(this_dir)
     path_copy = $LOAD_PATH.dup
     $LOAD_PATH.unshift(parent_dir) unless $LOAD_PATH.include?(parent_dir)
@@ -17,7 +19,7 @@ module DependenciesTestHelpers
   end
 
   def with_autoloading_fixtures(&block)
-    with_loading 'autoloading_fixtures', &block
+    with_loading "autoloading_fixtures", &block
   end
 
   def remove_constants(*constants)
@@ -25,4 +27,4 @@ module DependenciesTestHelpers
       Object.send(:remove_const, constant) if Object.const_defined?(constant)
     end
   end
-end
\ No newline at end of file
+end
diff --git a/activesupport/test/deprecation/method_wrappers_test.rb b/activesupport/test/deprecation/method_wrappers_test.rb
index 9a4ca2b217..439e117c1d 100644
--- a/activesupport/test/deprecation/method_wrappers_test.rb
+++ b/activesupport/test/deprecation/method_wrappers_test.rb
@@ -1,17 +1,29 @@
-require 'abstract_unit'
-require 'active_support/deprecation'
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "active_support/deprecation"
 
 class MethodWrappersTest < ActiveSupport::TestCase
   def setup
     @klass = Class.new do
       def new_method; "abc" end
       alias_method :old_method, :new_method
+
+      protected
+
+        def new_protected_method; "abc" end
+        alias_method :old_protected_method, :new_protected_method
+
+      private
+
+        def new_private_method; "abc" end
+        alias_method :old_private_method, :new_private_method
     end
   end
 
   def test_deprecate_methods_warning_default
     warning = /old_method is deprecated and will be removed from Rails \d.\d \(use new_method instead\)/
-    ActiveSupport::Deprecation.deprecate_methods(@klass, :old_method => :new_method)
+    ActiveSupport::Deprecation.deprecate_methods(@klass, old_method: :new_method)
 
     assert_deprecated(warning) { assert_equal "abc", @klass.new.old_method }
   end
@@ -19,7 +31,7 @@ class MethodWrappersTest < ActiveSupport::TestCase
   def test_deprecate_methods_warning_with_optional_deprecator
     warning = /old_method is deprecated and will be removed from MyGem next-release \(use new_method instead\)/
     deprecator = ActiveSupport::Deprecation.new("next-release", "MyGem")
-    ActiveSupport::Deprecation.deprecate_methods(@klass, :old_method => :new_method, :deprecator => deprecator)
+    ActiveSupport::Deprecation.deprecate_methods(@klass, old_method: :new_method, deprecator: deprecator)
 
     assert_deprecated(warning, deprecator) { assert_equal "abc", @klass.new.old_method }
   end
@@ -27,8 +39,20 @@ class MethodWrappersTest < ActiveSupport::TestCase
   def test_deprecate_methods_warning_when_deprecated_with_custom_deprecator
     warning = /old_method is deprecated and will be removed from MyGem next-release \(use new_method instead\)/
     deprecator = ActiveSupport::Deprecation.new("next-release", "MyGem")
-    deprecator.deprecate_methods(@klass, :old_method => :new_method)
+    deprecator.deprecate_methods(@klass, old_method: :new_method)
 
     assert_deprecated(warning, deprecator) { assert_equal "abc", @klass.new.old_method }
   end
+
+  def test_deprecate_methods_protected_method
+    ActiveSupport::Deprecation.deprecate_methods(@klass, old_protected_method: :new_protected_method)
+
+    assert(@klass.protected_method_defined?(:old_protected_method))
+  end
+
+  def test_deprecate_methods_private_method
+    ActiveSupport::Deprecation.deprecate_methods(@klass, old_private_method: :new_private_method)
+
+    assert(@klass.private_method_defined?(:old_private_method))
+  end
 end
diff --git a/activesupport/test/deprecation/proxy_wrappers_test.rb b/activesupport/test/deprecation/proxy_wrappers_test.rb
index e4f0f0f7c2..2f866775f6 100644
--- a/activesupport/test/deprecation/proxy_wrappers_test.rb
+++ b/activesupport/test/deprecation/proxy_wrappers_test.rb
@@ -1,5 +1,7 @@
-require 'abstract_unit'
-require 'active_support/deprecation'
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "active_support/deprecation"
 
 class ProxyWrappersTest < ActiveSupport::TestCase
   Waffles     = false
diff --git a/activesupport/test/deprecation_test.rb b/activesupport/test/deprecation_test.rb
index dbde3d2e15..f2267a822f 100644
--- a/activesupport/test/deprecation_test.rb
+++ b/activesupport/test/deprecation_test.rb
@@ -1,22 +1,24 @@
-require 'abstract_unit'
-require 'active_support/testing/stream'
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "active_support/testing/stream"
 
 class Deprecatee
   def initialize
     @request = ActiveSupport::Deprecation::DeprecatedInstanceVariableProxy.new(self, :request)
-    @_request = 'there we go'
+    @_request = "there we go"
   end
   def request; @_request end
   def old_request; @request end
 
   def partially(foo = nil)
-    ActiveSupport::Deprecation.warn('calling with foo=nil is out') if foo.nil?
+    ActiveSupport::Deprecation.warn("calling with foo=nil is out") if foo.nil?
   end
 
   def not() 2 end
   def none() 1 end
   def one(a) a end
-  def multi(a,b,c) [a,b,c] end
+  def multi(a, b, c) [a, b, c] end
   deprecate :none, :one, :multi
 
   def a; end
@@ -24,7 +26,7 @@ class Deprecatee
   def c; end
   def d; end
   def e; end
-  deprecate :a, :b, :c => :e, :d => "you now need to do something extra for this one"
+  deprecate :a, :b, c: :e, d: "you now need to do something extra for this one"
 
   def f=(v); end
   deprecate :f=
@@ -32,9 +34,20 @@ class Deprecatee
   module B
     C = 1
   end
-  A = ActiveSupport::Deprecation::DeprecatedConstantProxy.new('Deprecatee::A', 'Deprecatee::B::C')
+  A = ActiveSupport::Deprecation::DeprecatedConstantProxy.new("Deprecatee::A", "Deprecatee::B::C")
 end
 
+class DeprecateeWithAccessor
+  include ActiveSupport::Deprecation::DeprecatedConstantAccessor
+
+  module B
+    C = 1
+  end
+  deprecate_constant "A", "DeprecateeWithAccessor::B::C"
+
+  class NewException < StandardError; end
+  deprecate_constant "OldException", "DeprecateeWithAccessor::NewException"
+end
 
 class DeprecationTest < ActiveSupport::TestCase
   include ActiveSupport::Testing::Stream
@@ -74,12 +87,12 @@ class DeprecationTest < ActiveSupport::TestCase
     end
 
     assert_deprecated(/multi is deprecated/) do
-      assert_equal [1,2,3], @dtc.multi(1,2,3)
+      assert_equal [1, 2, 3], @dtc.multi(1, 2, 3)
     end
   end
 
   def test_deprecate_object
-    deprecated_object = ActiveSupport::Deprecation::DeprecatedObjectProxy.new(Object.new, ':bomb:')
+    deprecated_object = ActiveSupport::Deprecation::DeprecatedObjectProxy.new(Object.new, ":bomb:")
     assert_deprecated(/:bomb:/) { deprecated_object.to_s }
   end
 
@@ -89,26 +102,28 @@ class DeprecationTest < ActiveSupport::TestCase
   end
 
   def test_several_behaviors
-    @a, @b = nil, nil
+    @a, @b, @c = nil, nil, nil
 
     ActiveSupport::Deprecation.behavior = [
-      Proc.new { |msg, callstack| @a = msg },
-      Proc.new { |msg, callstack| @b = msg }
+      lambda { |msg, callstack, horizon, gem| @a = msg },
+      lambda { |msg, callstack| @b = msg },
+      lambda { |*args| @c = args },
     ]
 
     @dtc.partially
     assert_match(/foo=nil/, @a)
     assert_match(/foo=nil/, @b)
+    assert_equal 4, @c.size
   end
 
   def test_raise_behaviour
     ActiveSupport::Deprecation.behavior = :raise
 
-    message   = 'Revise this deprecated stuff now!'
+    message   = "Revise this deprecated stuff now!"
     callstack = caller_locations
 
     e = assert_raise ActiveSupport::DeprecationException do
-      ActiveSupport::Deprecation.behavior.first.call(message, callstack)
+      ActiveSupport::Deprecation.behavior.first.call(message, callstack, "horizon", "gem")
     end
     assert_equal message, e.message
     assert_equal callstack.map(&:to_s), e.backtrace.map(&:to_s)
@@ -119,7 +134,7 @@ class DeprecationTest < ActiveSupport::TestCase
     behavior = ActiveSupport::Deprecation.behavior.first
 
     content = capture(:stderr) {
-      assert_nil behavior.call('Some error!', ['call stack!'])
+      assert_nil behavior.call("Some error!", ["call stack!"], "horizon", "gem")
     }
     assert_match(/Some error!/, content)
     assert_match(/call stack!/, content)
@@ -129,7 +144,7 @@ class DeprecationTest < ActiveSupport::TestCase
     ActiveSupport::Deprecation.behavior = :stderr
 
     content = capture(:stderr) {
-      ActiveSupport::Deprecation.warn('Instance error!', ['instance call stack!'])
+      ActiveSupport::Deprecation.warn("Instance error!", ["instance call stack!"])
     }
 
     assert_match(/Instance error!/, content)
@@ -141,16 +156,37 @@ class DeprecationTest < ActiveSupport::TestCase
     behavior = ActiveSupport::Deprecation.behavior.first
 
     stderr_output = capture(:stderr) {
-      assert_nil behavior.call('Some error!', ['call stack!'])
+      assert_nil behavior.call("Some error!", ["call stack!"], "horizon", "gem")
     }
     assert stderr_output.empty?
   end
 
+  def test_default_notify_behavior
+    ActiveSupport::Deprecation.behavior = :notify
+    behavior = ActiveSupport::Deprecation.behavior.first
+
+    begin
+      events = []
+      ActiveSupport::Notifications.subscribe("deprecation.my_gem_custom") { |_, **args|
+        events << args
+      }
+
+      assert_nil behavior.call("Some error!", ["call stack!"], "horizon", "MyGem::Custom")
+      assert_equal 1, events.size
+      assert_equal "Some error!", events.first[:message]
+      assert_equal ["call stack!"], events.first[:callstack]
+      assert_equal "horizon", events.first[:deprecation_horizon]
+      assert_equal "MyGem::Custom", events.first[:gem_name]
+    ensure
+      ActiveSupport::Notifications.unsubscribe("deprecation.my_gem_custom")
+    end
+  end
+
   def test_deprecated_instance_variable_proxy
     assert_not_deprecated { @dtc.request.size }
 
-    assert_deprecated('@request.size') { assert_equal @dtc.request.size, @dtc.old_request.size }
-    assert_deprecated('@request.to_s') { assert_equal @dtc.request.to_s, @dtc.old_request.to_s }
+    assert_deprecated("@request.size") { assert_equal @dtc.request.size, @dtc.old_request.size }
+    assert_deprecated("@request.to_s") { assert_equal @dtc.request.to_s, @dtc.old_request.to_s }
   end
 
   def test_deprecated_instance_variable_proxy_shouldnt_warn_on_inspect
@@ -159,10 +195,21 @@ class DeprecationTest < ActiveSupport::TestCase
 
   def test_deprecated_constant_proxy
     assert_not_deprecated { Deprecatee::B::C }
-    assert_deprecated('Deprecatee::A') { assert_equal Deprecatee::B::C, Deprecatee::A }
+    assert_deprecated("Deprecatee::A") { assert_equal Deprecatee::B::C, Deprecatee::A }
     assert_not_deprecated { assert_equal Deprecatee::B::C.class, Deprecatee::A.class }
   end
 
+  def test_deprecated_constant_accessor
+    assert_not_deprecated { DeprecateeWithAccessor::B::C }
+    assert_deprecated("DeprecateeWithAccessor::A") { assert_equal DeprecateeWithAccessor::B::C, DeprecateeWithAccessor::A }
+  end
+
+  def test_deprecated_constant_accessor_exception
+    raise DeprecateeWithAccessor::NewException.new("Test")
+  rescue DeprecateeWithAccessor::OldException => e
+    assert_kind_of DeprecateeWithAccessor::NewException, e
+  end
+
   def test_assert_deprecated_raises_when_method_not_deprecated
     assert_raises(Minitest::Assertion) { assert_deprecated { @dtc.not } }
   end
@@ -178,12 +225,12 @@ class DeprecationTest < ActiveSupport::TestCase
   end
 
   def test_assert_deprecated_matches_any_warning
-    assert_deprecated 'abc' do
-      ActiveSupport::Deprecation.warn 'abc'
-      ActiveSupport::Deprecation.warn 'def'
+    assert_deprecated "abc" do
+      ActiveSupport::Deprecation.warn "abc"
+      ActiveSupport::Deprecation.warn "def"
     end
   rescue Minitest::Assertion
-    flunk 'assert_deprecated should match any warning in block, not just the last one'
+    flunk "assert_deprecated should match any warning in block, not just the last one"
   end
 
   def test_assert_not_deprecated_returns_result_of_block
@@ -191,17 +238,17 @@ class DeprecationTest < ActiveSupport::TestCase
   end
 
   def test_assert_deprecated_returns_result_of_block
-    result = assert_deprecated('abc') do
-      ActiveSupport::Deprecation.warn 'abc'
+    result = assert_deprecated("abc") do
+      ActiveSupport::Deprecation.warn "abc"
       123
     end
     assert_equal 123, result
   end
 
   def test_assert_deprecated_warn_work_with_default_behavior
-    ActiveSupport::Deprecation.instance_variable_set('@behavior', nil)
-    assert_deprecated('abc') do
-      ActiveSupport::Deprecation.warn 'abc'
+    ActiveSupport::Deprecation.instance_variable_set("@behavior", nil)
+    assert_deprecated("abc") do
+      ActiveSupport::Deprecation.warn "abc"
     end
   end
 
@@ -280,12 +327,22 @@ class DeprecationTest < ActiveSupport::TestCase
   def test_deprecated_constant_with_deprecator_given
     deprecator = deprecator_with_messages
     klass = Class.new
-    klass.const_set(:OLD, ActiveSupport::Deprecation::DeprecatedConstantProxy.new('klass::OLD', 'Object', deprecator) )
+    klass.const_set(:OLD, ActiveSupport::Deprecation::DeprecatedConstantProxy.new("klass::OLD", "Object", deprecator))
     assert_difference("deprecator.messages.size") do
       klass::OLD.to_s
     end
   end
 
+  def test_deprecated_constant_with_custom_message
+    deprecator = deprecator_with_messages
+
+    klass = Class.new
+    klass.const_set(:OLD, ActiveSupport::Deprecation::DeprecatedConstantProxy.new("klass::OLD", "Object", deprecator, message: "foo"))
+
+    klass::OLD.to_s
+    assert_match "foo", deprecator.messages.last
+  end
+
   def test_deprecated_instance_variable_with_instance_deprecator
     deprecator = deprecator_with_messages
 
@@ -353,7 +410,7 @@ class DeprecationTest < ActiveSupport::TestCase
   end
 
   def test_custom_gem_name
-    deprecator = ActiveSupport::Deprecation.new('2.0', 'Custom')
+    deprecator = ActiveSupport::Deprecation.new("2.0", "Custom")
 
     deprecator.send(:deprecated_method_warning, :deprecated_method, "You are calling deprecated method").tap do |message|
       assert_match(/is deprecated and will be removed from Custom/, message)
@@ -364,11 +421,10 @@ class DeprecationTest < ActiveSupport::TestCase
     def deprecator_with_messages
       klass = Class.new(ActiveSupport::Deprecation)
       deprecator = klass.new
-      deprecator.behavior = Proc.new{|message, callstack| deprecator.messages << message}
+      deprecator.behavior = Proc.new { |message, callstack| deprecator.messages << message }
       def deprecator.messages
         @messages ||= []
       end
       deprecator
     end
-
 end
diff --git a/activesupport/test/descendants_tracker_test_cases.rb b/activesupport/test/descendants_tracker_test_cases.rb
index 69e046998e..1f8b4a8605 100644
--- a/activesupport/test/descendants_tracker_test_cases.rb
+++ b/activesupport/test/descendants_tracker_test_cases.rb
@@ -1,4 +1,6 @@
-require 'set'
+# frozen_string_literal: true
+
+require "set"
 
 module DescendantsTrackerTestCases
   class Parent
@@ -40,26 +42,26 @@ module DescendantsTrackerTestCases
     end
   end
 
-  protected
-
-  def assert_equal_sets(expected, actual)
-    assert_equal Set.new(expected), Set.new(actual)
-  end
+  private
 
-  def mark_as_autoloaded(*klasses)
-    # If ActiveSupport::Dependencies is not loaded, forget about autoloading.
-    # This allows using AS::DescendantsTracker without AS::Dependencies.
-    if defined? ActiveSupport::Dependencies
-      old_autoloaded = ActiveSupport::Dependencies.autoloaded_constants.dup
-      ActiveSupport::Dependencies.autoloaded_constants = klasses.map(&:name)
+    def assert_equal_sets(expected, actual)
+      assert_equal Set.new(expected), Set.new(actual)
     end
 
-    old_descendants = ActiveSupport::DescendantsTracker.class_eval("@@direct_descendants").dup
-    old_descendants.each { |k, v| old_descendants[k] = v.dup }
+    def mark_as_autoloaded(*klasses)
+      # If ActiveSupport::Dependencies is not loaded, forget about autoloading.
+      # This allows using AS::DescendantsTracker without AS::Dependencies.
+      if defined? ActiveSupport::Dependencies
+        old_autoloaded = ActiveSupport::Dependencies.autoloaded_constants.dup
+        ActiveSupport::Dependencies.autoloaded_constants = klasses.map(&:name)
+      end
 
-    yield
-  ensure
-    ActiveSupport::Dependencies.autoloaded_constants = old_autoloaded if defined? ActiveSupport::Dependencies
-    ActiveSupport::DescendantsTracker.class_eval("@@direct_descendants").replace(old_descendants)
-  end
+      old_descendants = ActiveSupport::DescendantsTracker.class_eval("@@direct_descendants").dup
+      old_descendants.each { |k, v| old_descendants[k] = v.dup }
+
+      yield
+    ensure
+      ActiveSupport::Dependencies.autoloaded_constants = old_autoloaded if defined? ActiveSupport::Dependencies
+      ActiveSupport::DescendantsTracker.class_eval("@@direct_descendants").replace(old_descendants)
+    end
 end
diff --git a/activesupport/test/descendants_tracker_with_autoloading_test.rb b/activesupport/test/descendants_tracker_with_autoloading_test.rb
index a2ae066a21..7c396b7c8e 100644
--- a/activesupport/test/descendants_tracker_with_autoloading_test.rb
+++ b/activesupport/test/descendants_tracker_with_autoloading_test.rb
@@ -1,7 +1,9 @@
-require 'abstract_unit'
-require 'active_support/descendants_tracker'
-require 'active_support/dependencies'
-require 'descendants_tracker_test_cases'
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "active_support/descendants_tracker"
+require "active_support/dependencies"
+require "descendants_tracker_test_cases"
 
 class DescendantsTrackerWithAutoloadingTest < ActiveSupport::TestCase
   include DescendantsTrackerTestCases
diff --git a/activesupport/test/descendants_tracker_without_autoloading_test.rb b/activesupport/test/descendants_tracker_without_autoloading_test.rb
index 00b449af51..f5c6a3045d 100644
--- a/activesupport/test/descendants_tracker_without_autoloading_test.rb
+++ b/activesupport/test/descendants_tracker_without_autoloading_test.rb
@@ -1,6 +1,8 @@
-require 'abstract_unit'
-require 'active_support/descendants_tracker'
-require 'descendants_tracker_test_cases'
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "active_support/descendants_tracker"
+require "descendants_tracker_test_cases"
 
 class DescendantsTrackerWithoutAutoloadingTest < ActiveSupport::TestCase
   include DescendantsTrackerTestCases
diff --git a/activesupport/test/digest_test.rb b/activesupport/test/digest_test.rb
new file mode 100644
index 0000000000..83ff2a8d83
--- /dev/null
+++ b/activesupport/test/digest_test.rb
@@ -0,0 +1,27 @@
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "openssl"
+
+class DigestTest < ActiveSupport::TestCase
+  class InvalidDigest; end
+  def test_with_default_hash_digest_class
+    assert_equal ::Digest::MD5.hexdigest("hello friend"), ActiveSupport::Digest.hexdigest("hello friend")
+  end
+
+  def test_with_custom_hash_digest_class
+    original_hash_digest_class = ActiveSupport::Digest.hash_digest_class
+
+    ActiveSupport::Digest.hash_digest_class = ::Digest::SHA1
+    digest = ActiveSupport::Digest.hexdigest("hello friend")
+
+    assert_equal 32, digest.length
+    assert_equal ::Digest::SHA1.hexdigest("hello friend")[0...32], digest
+  ensure
+    ActiveSupport::Digest.hash_digest_class = original_hash_digest_class
+  end
+
+  def test_should_raise_argument_error_if_custom_digest_is_missing_hexdigest_method
+    assert_raises(ArgumentError) { ActiveSupport::Digest.hash_digest_class = InvalidDigest }
+  end
+end
diff --git a/activesupport/test/encrypted_configuration_test.rb b/activesupport/test/encrypted_configuration_test.rb
new file mode 100644
index 0000000000..93ccf457de
--- /dev/null
+++ b/activesupport/test/encrypted_configuration_test.rb
@@ -0,0 +1,67 @@
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "active_support/encrypted_configuration"
+
+class EncryptedConfigurationTest < ActiveSupport::TestCase
+  setup do
+    @credentials_config_path = File.join(Dir.tmpdir, "credentials.yml.enc")
+
+    @credentials_key_path = File.join(Dir.tmpdir, "master.key")
+    File.write(@credentials_key_path, ActiveSupport::EncryptedConfiguration.generate_key)
+
+    @credentials = ActiveSupport::EncryptedConfiguration.new(
+      config_path: @credentials_config_path, key_path: @credentials_key_path,
+      env_key: "RAILS_MASTER_KEY", raise_if_missing_key: true
+    )
+  end
+
+  teardown do
+    FileUtils.rm_rf @credentials_config_path
+    FileUtils.rm_rf @credentials_key_path
+  end
+
+  test "reading configuration by env key" do
+    FileUtils.rm_rf @credentials_key_path
+
+    begin
+      ENV["RAILS_MASTER_KEY"] = ActiveSupport::EncryptedConfiguration.generate_key
+      @credentials.write({ something: { good: true, bad: false } }.to_yaml)
+
+      assert @credentials[:something][:good]
+      assert_not @credentials.dig(:something, :bad)
+      assert_nil @credentials.fetch(:nothing, nil)
+    ensure
+      ENV["RAILS_MASTER_KEY"] = nil
+    end
+  end
+
+  test "reading configuration by key file" do
+    @credentials.write({ something: { good: true } }.to_yaml)
+
+    assert @credentials.something[:good]
+  end
+
+  test "change configuration by key file" do
+    @credentials.write({ something: { good: true } }.to_yaml)
+    @credentials.change do |config_file|
+      config = YAML.load(config_file.read)
+      config_file.write config.merge(new: "things").to_yaml
+    end
+
+    assert @credentials.something[:good]
+    assert_equal "things", @credentials[:new]
+  end
+
+  test "raise error when writing an invalid format value" do
+    assert_raise(Psych::SyntaxError) do
+      @credentials.change do |config_file|
+        config_file.write "login: *login\n  username: dummy"
+      end
+    end
+  end
+
+  test "raises key error when accessing config via bang method" do
+    assert_raise(KeyError) { @credentials.something! }
+  end
+end
diff --git a/activesupport/test/encrypted_file_test.rb b/activesupport/test/encrypted_file_test.rb
new file mode 100644
index 0000000000..ba3bbef903
--- /dev/null
+++ b/activesupport/test/encrypted_file_test.rb
@@ -0,0 +1,59 @@
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "active_support/encrypted_file"
+
+class EncryptedFileTest < ActiveSupport::TestCase
+  setup do
+    @content = "One little fox jumped over the hedge"
+
+    @content_path = File.join(Dir.tmpdir, "content.txt.enc")
+
+    @key_path = File.join(Dir.tmpdir, "content.txt.key")
+    File.write(@key_path, ActiveSupport::EncryptedFile.generate_key)
+
+    @encrypted_file = ActiveSupport::EncryptedFile.new(
+      content_path: @content_path, key_path: @key_path, env_key: "CONTENT_KEY", raise_if_missing_key: true
+    )
+  end
+
+  teardown do
+    FileUtils.rm_rf @content_path
+    FileUtils.rm_rf @key_path
+  end
+
+  test "reading content by env key" do
+    FileUtils.rm_rf @key_path
+
+    begin
+      ENV["CONTENT_KEY"] = ActiveSupport::EncryptedFile.generate_key
+      @encrypted_file.write @content
+
+      assert_equal @content, @encrypted_file.read
+    ensure
+      ENV["CONTENT_KEY"] = nil
+    end
+  end
+
+  test "reading content by key file" do
+    @encrypted_file.write(@content)
+    assert_equal @content, @encrypted_file.read
+  end
+
+  test "change content by key file" do
+    @encrypted_file.write(@content)
+    @encrypted_file.change do |file|
+      file.write(file.read + " and went by the lake")
+    end
+
+    assert_equal "#{@content} and went by the lake", @encrypted_file.read
+  end
+
+  test "raise MissingKeyError when key is missing" do
+    assert_raise(ActiveSupport::EncryptedFile::MissingKeyError) do
+      ActiveSupport::EncryptedFile.new(
+        content_path: @content_path, key_path: "", env_key: "", raise_if_missing_key: true
+      ).read
+    end
+  end
+end
diff --git a/activesupport/test/evented_file_update_checker_test.rb b/activesupport/test/evented_file_update_checker_test.rb
index 2cb2d8167f..9b560f7f42 100644
--- a/activesupport/test/evented_file_update_checker_test.rb
+++ b/activesupport/test/evented_file_update_checker_test.rb
@@ -1,12 +1,15 @@
-require 'abstract_unit'
-require 'pathname'
-require 'file_update_checker_shared_tests'
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "pathname"
+require "file_update_checker_shared_tests"
 
 class EventedFileUpdateCheckerTest < ActiveSupport::TestCase
   include FileUpdateCheckerSharedTests
 
   def setup
-    skip if ENV['LISTEN'] == '0'
+    skip if ENV["LISTEN"] == "0"
+    require "listen"
     super
   end
 
@@ -30,18 +33,15 @@ class EventedFileUpdateCheckerTest < ActiveSupport::TestCase
     wait # wait for the events to fire
   end
 
-  def rm_f(files)
-    super
-    wait
-  end
+  test "notifies forked processes" do
+    jruby_skip "Forking not available on JRuby"
 
-  test 'notifies forked processes' do
     FileUtils.touch(tmpfiles)
 
-    checker = new_checker(tmpfiles) { }
+    checker = new_checker(tmpfiles) {}
     assert !checker.updated?
 
-    # Pipes used for flow controll across fork.
+    # Pipes used for flow control across fork.
     boot_reader,  boot_writer  = IO.pipe
     touch_reader, touch_writer = IO.pipe
 
@@ -87,33 +87,33 @@ class EventedFileUpdateCheckerPathHelperTest < ActiveSupport::TestCase
     @ph = ActiveSupport::EventedFileUpdateChecker::PathHelper.new
   end
 
-  test '#xpath returns the expanded path as a Pathname object' do
+  test "#xpath returns the expanded path as a Pathname object" do
     assert_equal pn(__FILE__).expand_path, @ph.xpath(__FILE__)
   end
 
-  test '#normalize_extension returns a bare extension as is' do
-    assert_equal 'rb', @ph.normalize_extension('rb')
+  test "#normalize_extension returns a bare extension as is" do
+    assert_equal "rb", @ph.normalize_extension("rb")
   end
 
-  test '#normalize_extension removes a leading dot' do
-    assert_equal 'rb', @ph.normalize_extension('.rb')
+  test "#normalize_extension removes a leading dot" do
+    assert_equal "rb", @ph.normalize_extension(".rb")
   end
 
-  test '#normalize_extension supports symbols' do
-    assert_equal 'rb', @ph.normalize_extension(:rb)
+  test "#normalize_extension supports symbols" do
+    assert_equal "rb", @ph.normalize_extension(:rb)
   end
 
-  test '#longest_common_subpath finds the longest common subpath, if there is one' do
+  test "#longest_common_subpath finds the longest common subpath, if there is one" do
     paths = %w(
       /foo/bar
       /foo/baz
       /foo/bar/baz/woo/zoo
     ).map { |path| pn(path) }
 
-    assert_equal pn('/foo'), @ph.longest_common_subpath(paths)
+    assert_equal pn("/foo"), @ph.longest_common_subpath(paths)
   end
 
-  test '#longest_common_subpath returns the root directory as an edge case' do
+  test "#longest_common_subpath returns the root directory as an edge case" do
     paths = %w(
       /foo/bar
       /foo/baz
@@ -121,30 +121,30 @@ class EventedFileUpdateCheckerPathHelperTest < ActiveSupport::TestCase
       /wadus
     ).map { |path| pn(path) }
 
-    assert_equal pn('/'), @ph.longest_common_subpath(paths)
+    assert_equal pn("/"), @ph.longest_common_subpath(paths)
   end
 
-  test '#longest_common_subpath returns nil for an empty collection' do
+  test "#longest_common_subpath returns nil for an empty collection" do
     assert_nil @ph.longest_common_subpath([])
   end
 
-  test '#existing_parent returns the most specific existing ascendant' do
+  test "#existing_parent returns the most specific existing ascendant" do
     wd = Pathname.getwd
 
     assert_equal wd, @ph.existing_parent(wd)
-    assert_equal wd, @ph.existing_parent(wd.join('non-existing/directory'))
-    assert_equal pn('/'), @ph.existing_parent(pn('/non-existing/directory'))
+    assert_equal wd, @ph.existing_parent(wd.join("non-existing/directory"))
+    assert_equal pn("/"), @ph.existing_parent(pn("/non-existing/directory"))
   end
 
-  test '#filter_out_descendants returns the same collection if there are no descendants (empty)' do
+  test "#filter_out_descendants returns the same collection if there are no descendants (empty)" do
     assert_equal [], @ph.filter_out_descendants([])
   end
 
-  test '#filter_out_descendants returns the same collection if there are no descendants (one)' do
-    assert_equal ['/foo'], @ph.filter_out_descendants(['/foo'])
+  test "#filter_out_descendants returns the same collection if there are no descendants (one)" do
+    assert_equal ["/foo"], @ph.filter_out_descendants(["/foo"])
   end
 
-  test '#filter_out_descendants returns the same collection if there are no descendants (several)' do
+  test "#filter_out_descendants returns the same collection if there are no descendants (several)" do
     paths = %w(
       /Rails.root/app/controllers
       /Rails.root/app/models
@@ -154,7 +154,7 @@ class EventedFileUpdateCheckerPathHelperTest < ActiveSupport::TestCase
     assert_equal paths, @ph.filter_out_descendants(paths)
   end
 
-  test '#filter_out_descendants filters out descendants preserving order' do
+  test "#filter_out_descendants filters out descendants preserving order" do
     paths = %w(
       /Rails.root/app/controllers
       /Rails.root/app/controllers/concerns
@@ -166,7 +166,7 @@ class EventedFileUpdateCheckerPathHelperTest < ActiveSupport::TestCase
     assert_equal paths.values_at(0, 2, 4), @ph.filter_out_descendants(paths)
   end
 
-  test '#filter_out_descendants works on path units' do
+  test "#filter_out_descendants works on path units" do
     paths = %w(
       /foo/bar
       /foo/barrrr
@@ -175,7 +175,7 @@ class EventedFileUpdateCheckerPathHelperTest < ActiveSupport::TestCase
     assert_equal paths, @ph.filter_out_descendants(paths)
   end
 
-  test '#filter_out_descendants deals correctly with the root directory' do
+  test "#filter_out_descendants deals correctly with the root directory" do
     paths = %w(
       /
       /foo
@@ -185,7 +185,7 @@ class EventedFileUpdateCheckerPathHelperTest < ActiveSupport::TestCase
     assert_equal paths.values_at(0), @ph.filter_out_descendants(paths)
   end
 
-  test '#filter_out_descendants preserves duplicates' do
+  test "#filter_out_descendants preserves duplicates" do
     paths = %w(
       /foo
       /foo/bar
diff --git a/activesupport/test/executor_test.rb b/activesupport/test/executor_test.rb
index d9b389461a..af441064dd 100644
--- a/activesupport/test/executor_test.rb
+++ b/activesupport/test/executor_test.rb
@@ -1,4 +1,6 @@
-require 'abstract_unit'
+# frozen_string_literal: true
+
+require "abstract_unit"
 
 class ExecutorTest < ActiveSupport::TestCase
   class DummyError < RuntimeError
@@ -21,7 +23,7 @@ class ExecutorTest < ActiveSupport::TestCase
     executor.to_run { @foo = true }
     executor.to_complete { result = @foo }
 
-    executor.wrap { }
+    executor.wrap {}
 
     assert result
   end
@@ -83,7 +85,7 @@ class ExecutorTest < ActiveSupport::TestCase
 
     executor.register_hook(hook)
 
-    executor.wrap { }
+    executor.wrap {}
 
     assert_equal :some_state, supplied_state
   end
@@ -103,9 +105,9 @@ class ExecutorTest < ActiveSupport::TestCase
 
     executor.register_hook(hook)
 
-    executor.wrap { }
+    executor.wrap {}
 
-    assert_equal nil, supplied_state
+    assert_nil supplied_state
   end
 
   def test_exception_skips_uninvoked_hook
@@ -127,7 +129,7 @@ class ExecutorTest < ActiveSupport::TestCase
     executor.register_hook(hook)
 
     assert_raises(DummyError) do
-      executor.wrap { }
+      executor.wrap {}
     end
 
     assert_equal :none, supplied_state
@@ -152,12 +154,69 @@ class ExecutorTest < ActiveSupport::TestCase
     end
 
     assert_raises(DummyError) do
-      executor.wrap { }
+      executor.wrap {}
     end
 
     assert_equal :some_state, supplied_state
   end
 
+  def test_hook_insertion_order
+    invoked = []
+    supplied_state = []
+
+    hook_class = Class.new do
+      attr_accessor :letter
+
+      define_method(:initialize) do |letter|
+        self.letter = letter
+      end
+
+      define_method(:run) do
+        invoked << :"run_#{letter}"
+        :"state_#{letter}"
+      end
+
+      define_method(:complete) do |state|
+        invoked << :"complete_#{letter}"
+        supplied_state << state
+      end
+    end
+
+    executor.register_hook(hook_class.new(:a))
+    executor.register_hook(hook_class.new(:b))
+    executor.register_hook(hook_class.new(:c), outer: true)
+    executor.register_hook(hook_class.new(:d))
+
+    executor.wrap {}
+
+    assert_equal [:run_c, :run_a, :run_b, :run_d, :complete_a, :complete_b, :complete_d, :complete_c], invoked
+    assert_equal [:state_a, :state_b, :state_d, :state_c], supplied_state
+  end
+
+  def test_class_serial_is_unaffected
+    skip if !defined?(RubyVM)
+
+    hook = Class.new do
+      define_method(:run) do
+        nil
+      end
+
+      define_method(:complete) do |state|
+        nil
+      end
+    end.new
+
+    executor.register_hook(hook)
+
+    before = RubyVM.stat(:class_serial)
+    executor.wrap {}
+    executor.wrap {}
+    executor.wrap {}
+    after = RubyVM.stat(:class_serial)
+
+    assert_equal before, after
+  end
+
   def test_separate_classes_can_wrap
     other_executor = Class.new(ActiveSupport::Executor)
 
diff --git a/activesupport/test/file_update_checker_shared_tests.rb b/activesupport/test/file_update_checker_shared_tests.rb
index 40ae0c7617..f8266dac06 100644
--- a/activesupport/test/file_update_checker_shared_tests.rb
+++ b/activesupport/test/file_update_checker_shared_tests.rb
@@ -1,4 +1,6 @@
-require 'fileutils'
+# frozen_string_literal: true
+
+require "fileutils"
 
 module FileUpdateCheckerSharedTests
   extend ActiveSupport::Testing::Declarative
@@ -22,8 +24,8 @@ module FileUpdateCheckerSharedTests
     end
   end
 
-  test 'should not execute the block if no paths are given' do
-    silence_warnings { require 'listen' }
+  test "should not execute the block if no paths are given" do
+    silence_warnings { require "listen" }
     i = 0
 
     checker = new_checker { i += 1 }
@@ -32,7 +34,7 @@ module FileUpdateCheckerSharedTests
     assert_equal 0, i
   end
 
-  test 'should not execute the block if no files change' do
+  test "should not execute the block if no files change" do
     i = 0
 
     FileUtils.touch(tmpfiles)
@@ -43,18 +45,19 @@ module FileUpdateCheckerSharedTests
     assert_equal 0, i
   end
 
-  test 'should execute the block once when files are created' do
+  test "should execute the block once when files are created" do
     i = 0
 
     checker = new_checker(tmpfiles) { i += 1 }
 
     touch(tmpfiles)
+    wait
 
     assert checker.execute_if_updated
     assert_equal 1, i
   end
 
-  test 'should execute the block once when files are modified' do
+  test "should execute the block once when files are modified" do
     i = 0
 
     FileUtils.touch(tmpfiles)
@@ -62,12 +65,13 @@ module FileUpdateCheckerSharedTests
     checker = new_checker(tmpfiles) { i += 1 }
 
     touch(tmpfiles)
+    wait
 
     assert checker.execute_if_updated
     assert_equal 1, i
   end
 
-  test 'should execute the block once when files are deleted' do
+  test "should execute the block once when files are deleted" do
     i = 0
 
     FileUtils.touch(tmpfiles)
@@ -75,25 +79,25 @@ module FileUpdateCheckerSharedTests
     checker = new_checker(tmpfiles) { i += 1 }
 
     rm_f(tmpfiles)
+    wait
 
     assert checker.execute_if_updated
     assert_equal 1, i
   end
 
-
-  test 'updated should become true when watched files are created' do
+  test "updated should become true when watched files are created" do
     i = 0
 
     checker = new_checker(tmpfiles) { i += 1 }
     assert !checker.updated?
 
     touch(tmpfiles)
+    wait
 
     assert checker.updated?
   end
 
-
-  test 'updated should become true when watched files are modified' do
+  test "updated should become true when watched files are modified" do
     i = 0
 
     FileUtils.touch(tmpfiles)
@@ -102,11 +106,12 @@ module FileUpdateCheckerSharedTests
     assert !checker.updated?
 
     touch(tmpfiles)
+    wait
 
     assert checker.updated?
   end
 
-  test 'updated should become true when watched files are deleted' do
+  test "updated should become true when watched files are deleted" do
     i = 0
 
     FileUtils.touch(tmpfiles)
@@ -115,11 +120,12 @@ module FileUpdateCheckerSharedTests
     assert !checker.updated?
 
     rm_f(tmpfiles)
+    wait
 
     assert checker.updated?
   end
 
-  test 'should be robust to handle files with wrong modified time' do
+  test "should be robust to handle files with wrong modified time" do
     i = 0
 
     FileUtils.touch(tmpfiles)
@@ -131,12 +137,13 @@ module FileUpdateCheckerSharedTests
     checker = new_checker(tmpfiles) { i += 1 }
 
     touch(tmpfiles[1..-1])
+    wait
 
     assert checker.execute_if_updated
     assert_equal 1, i
   end
 
-  test 'should return max_time for files with mtime = Time.at(0)' do
+  test "should return max_time for files with mtime = Time.at(0)" do
     i = 0
 
     FileUtils.touch(tmpfiles)
@@ -147,80 +154,87 @@ module FileUpdateCheckerSharedTests
     checker = new_checker(tmpfiles) { i += 1 }
 
     touch(tmpfiles[1..-1])
+    wait
 
     assert checker.execute_if_updated
     assert_equal 1, i
   end
 
-  test 'should cache updated result until execute' do
+  test "should cache updated result until execute" do
     i = 0
 
     checker = new_checker(tmpfiles) { i += 1 }
     assert !checker.updated?
 
     touch(tmpfiles)
+    wait
 
     assert checker.updated?
     checker.execute
     assert !checker.updated?
   end
 
-  test 'should execute the block if files change in a watched directory one extension' do
+  test "should execute the block if files change in a watched directory one extension" do
     i = 0
 
     checker = new_checker([], tmpdir => :rb) { i += 1 }
 
-    touch(tmpfile('foo.rb'))
+    touch(tmpfile("foo.rb"))
+    wait
 
     assert checker.execute_if_updated
     assert_equal 1, i
   end
 
-  test 'should execute the block if files change in a watched directory several extensions' do
+  test "should execute the block if files change in a watched directory several extensions" do
     i = 0
 
     checker = new_checker([], tmpdir => [:rb, :txt]) { i += 1 }
 
-    touch(tmpfile('foo.rb'))
+    touch(tmpfile("foo.rb"))
+    wait
 
     assert checker.execute_if_updated
     assert_equal 1, i
 
-    touch(tmpfile('foo.txt'))
+    touch(tmpfile("foo.txt"))
+    wait
 
     assert checker.execute_if_updated
     assert_equal 2, i
   end
 
-  test 'should not execute the block if the file extension is not watched' do
+  test "should not execute the block if the file extension is not watched" do
     i = 0
 
     checker = new_checker([], tmpdir => :txt) { i += 1 }
 
-    touch(tmpfile('foo.rb'))
+    touch(tmpfile("foo.rb"))
+    wait
 
     assert !checker.execute_if_updated
     assert_equal 0, i
   end
 
-  test 'does not assume files exist on instantiation' do
+  test "does not assume files exist on instantiation" do
     i = 0
 
-    non_existing = tmpfile('non_existing.rb')
+    non_existing = tmpfile("non_existing.rb")
     checker = new_checker([non_existing]) { i += 1 }
 
     touch(non_existing)
+    wait
 
     assert checker.execute_if_updated
     assert_equal 1, i
   end
 
-  test 'detects files in new subdirectories' do
+  test "detects files in new subdirectories" do
     i = 0
 
     checker = new_checker([], tmpdir => :rb) { i += 1 }
 
-    subdir = tmpfile('subdir')
+    subdir = tmpfile("subdir")
     mkdir(subdir)
     wait
 
@@ -228,33 +242,43 @@ module FileUpdateCheckerSharedTests
     assert_equal 0, i
 
     touch(File.join(subdir, "nested.rb"))
+    wait
 
     assert checker.execute_if_updated
     assert_equal 1, i
   end
 
-  test 'looked up extensions are inherited in subdirectories not listening to them' do
+  test "looked up extensions are inherited in subdirectories not listening to them" do
     i = 0
 
-    subdir = tmpfile('subdir')
+    subdir = tmpfile("subdir")
     mkdir(subdir)
 
     checker = new_checker([], tmpdir => :rb, subdir => :txt) { i += 1 }
 
-    touch(tmpfile('new.txt'))
+    touch(tmpfile("new.txt"))
+    wait
 
     assert !checker.execute_if_updated
     assert_equal 0, i
 
     # subdir does not look for Ruby files, but its parent tmpdir does.
     touch(File.join(subdir, "nested.rb"))
+    wait
 
     assert checker.execute_if_updated
     assert_equal 1, i
 
     touch(File.join(subdir, "nested.txt"))
+    wait
 
     assert checker.execute_if_updated
     assert_equal 2, i
   end
+
+  test "initialize raises an ArgumentError if no block given" do
+    assert_raise ArgumentError do
+      new_checker([])
+    end
+  end
 end
diff --git a/activesupport/test/file_update_checker_test.rb b/activesupport/test/file_update_checker_test.rb
index 752f7836cd..ec1df0df67 100644
--- a/activesupport/test/file_update_checker_test.rb
+++ b/activesupport/test/file_update_checker_test.rb
@@ -1,5 +1,7 @@
-require 'abstract_unit'
-require 'file_update_checker_shared_tests'
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "file_update_checker_shared_tests"
 
 class FileUpdateCheckerTest < ActiveSupport::TestCase
   include FileUpdateCheckerSharedTests
diff --git a/activesupport/test/fixtures/autoload/another_class.rb b/activesupport/test/fixtures/autoload/another_class.rb
index a240b3de41..cf38336cf8 100644
--- a/activesupport/test/fixtures/autoload/another_class.rb
+++ b/activesupport/test/fixtures/autoload/another_class.rb
@@ -1,2 +1,4 @@
+# frozen_string_literal: true
+
 class Fixtures::AnotherClass
-end
\ No newline at end of file
+end
diff --git a/activesupport/test/fixtures/autoload/some_class.rb b/activesupport/test/fixtures/autoload/some_class.rb
index 13b3c73ef5..ff25eb995e 100644
--- a/activesupport/test/fixtures/autoload/some_class.rb
+++ b/activesupport/test/fixtures/autoload/some_class.rb
@@ -1,2 +1,4 @@
+# frozen_string_literal: true
+
 class Fixtures::Autoload::SomeClass
-end
\ No newline at end of file
+end
diff --git a/activesupport/test/gzip_test.rb b/activesupport/test/gzip_test.rb
index 0e3cf3b429..05ce12fe86 100644
--- a/activesupport/test/gzip_test.rb
+++ b/activesupport/test/gzip_test.rb
@@ -1,5 +1,7 @@
-require 'abstract_unit'
-require 'active_support/core_ext/object/blank'
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "active_support/core_ext/object/blank"
 
 class GzipTest < ActiveSupport::TestCase
   def test_compress_should_decompress_to_the_same_value
@@ -13,14 +15,14 @@ class GzipTest < ActiveSupport::TestCase
   end
 
   def test_compress_should_return_a_binary_string
-    compressed = ActiveSupport::Gzip.compress('')
+    compressed = ActiveSupport::Gzip.compress("")
 
-    assert_equal Encoding.find('binary'), compressed.encoding
+    assert_equal Encoding.find("binary"), compressed.encoding
     assert !compressed.blank?, "a compressed blank string should not be blank"
   end
 
   def test_compress_should_return_gzipped_string_by_compression_level
-    source_string = "Hello World"*100
+    source_string = "Hello World" * 100
 
     gzipped_by_speed = ActiveSupport::Gzip.compress(source_string, Zlib::BEST_SPEED)
     assert_equal 1, Zlib::GzipReader.new(StringIO.new(gzipped_by_speed)).level
@@ -30,4 +32,14 @@ class GzipTest < ActiveSupport::TestCase
 
     assert_equal true, (gzipped_by_best_compression.bytesize < gzipped_by_speed.bytesize)
   end
+
+  def test_decompress_checks_crc
+    compressed = ActiveSupport::Gzip.compress("Hello World")
+    first_crc_byte_index = compressed.bytesize - 8
+    compressed.setbyte(first_crc_byte_index, compressed.getbyte(first_crc_byte_index) ^ 0xff)
+
+    assert_raises(Zlib::GzipFile::CRCError) do
+      ActiveSupport::Gzip.decompress(compressed)
+    end
+  end
 end
diff --git a/activesupport/test/hash_with_indifferent_access_test.rb b/activesupport/test/hash_with_indifferent_access_test.rb
new file mode 100644
index 0000000000..41d653fa59
--- /dev/null
+++ b/activesupport/test/hash_with_indifferent_access_test.rb
@@ -0,0 +1,803 @@
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "active_support/core_ext/hash"
+require "bigdecimal"
+require "active_support/core_ext/string/access"
+require "active_support/ordered_hash"
+require "active_support/core_ext/object/conversions"
+require "active_support/core_ext/object/deep_dup"
+require "active_support/inflections"
+
+class HashWithIndifferentAccessTest < ActiveSupport::TestCase
+  HashWithIndifferentAccess = ActiveSupport::HashWithIndifferentAccess
+
+  class IndifferentHash < ActiveSupport::HashWithIndifferentAccess
+  end
+
+  class SubclassingArray < Array
+  end
+
+  class SubclassingHash < Hash
+  end
+
+  class NonIndifferentHash < Hash
+    def nested_under_indifferent_access
+      self
+    end
+  end
+
+  class HashByConversion
+    def initialize(hash)
+      @hash = hash
+    end
+
+    def to_hash
+      @hash
+    end
+  end
+
+  def setup
+    @strings = { "a" => 1, "b" => 2 }
+    @nested_strings = { "a" => { "b" => { "c" => 3 } } }
+    @symbols = { a: 1, b: 2 }
+    @nested_symbols = { a: { b: { c: 3 } } }
+    @mixed = { :a => 1, "b" => 2 }
+    @nested_mixed = { "a" => { b: { "c" => 3 } } }
+    @integers = { 0 => 1, 1 => 2 }
+    @nested_integers = { 0 => { 1 => { 2 => 3 } } }
+    @illegal_symbols = { [] => 3 }
+    @nested_illegal_symbols = { [] => { [] => 3 } }
+  end
+
+  def test_symbolize_keys_for_hash_with_indifferent_access
+    assert_instance_of Hash, @symbols.with_indifferent_access.symbolize_keys
+    assert_equal @symbols, @symbols.with_indifferent_access.symbolize_keys
+    assert_equal @symbols, @strings.with_indifferent_access.symbolize_keys
+    assert_equal @symbols, @mixed.with_indifferent_access.symbolize_keys
+  end
+
+  def test_deep_symbolize_keys_for_hash_with_indifferent_access
+    assert_instance_of Hash, @nested_symbols.with_indifferent_access.deep_symbolize_keys
+    assert_equal @nested_symbols, @nested_symbols.with_indifferent_access.deep_symbolize_keys
+    assert_equal @nested_symbols, @nested_strings.with_indifferent_access.deep_symbolize_keys
+    assert_equal @nested_symbols, @nested_mixed.with_indifferent_access.deep_symbolize_keys
+  end
+
+  def test_symbolize_keys_bang_for_hash_with_indifferent_access
+    assert_raise(NoMethodError) { @symbols.with_indifferent_access.dup.symbolize_keys! }
+    assert_raise(NoMethodError) { @strings.with_indifferent_access.dup.symbolize_keys! }
+    assert_raise(NoMethodError) { @mixed.with_indifferent_access.dup.symbolize_keys! }
+  end
+
+  def test_deep_symbolize_keys_bang_for_hash_with_indifferent_access
+    assert_raise(NoMethodError) { @nested_symbols.with_indifferent_access.deep_dup.deep_symbolize_keys! }
+    assert_raise(NoMethodError) { @nested_strings.with_indifferent_access.deep_dup.deep_symbolize_keys! }
+    assert_raise(NoMethodError) { @nested_mixed.with_indifferent_access.deep_dup.deep_symbolize_keys! }
+  end
+
+  def test_symbolize_keys_preserves_keys_that_cant_be_symbolized_for_hash_with_indifferent_access
+    assert_equal @illegal_symbols, @illegal_symbols.with_indifferent_access.symbolize_keys
+    assert_raise(NoMethodError) { @illegal_symbols.with_indifferent_access.dup.symbolize_keys! }
+  end
+
+  def test_deep_symbolize_keys_preserves_keys_that_cant_be_symbolized_for_hash_with_indifferent_access
+    assert_equal @nested_illegal_symbols, @nested_illegal_symbols.with_indifferent_access.deep_symbolize_keys
+    assert_raise(NoMethodError) { @nested_illegal_symbols.with_indifferent_access.deep_dup.deep_symbolize_keys! }
+  end
+
+  def test_symbolize_keys_preserves_integer_keys_for_hash_with_indifferent_access
+    assert_equal @integers, @integers.with_indifferent_access.symbolize_keys
+    assert_raise(NoMethodError) { @integers.with_indifferent_access.dup.symbolize_keys! }
+  end
+
+  def test_deep_symbolize_keys_preserves_integer_keys_for_hash_with_indifferent_access
+    assert_equal @nested_integers, @nested_integers.with_indifferent_access.deep_symbolize_keys
+    assert_raise(NoMethodError) { @nested_integers.with_indifferent_access.deep_dup.deep_symbolize_keys! }
+  end
+
+  def test_stringify_keys_for_hash_with_indifferent_access
+    assert_instance_of ActiveSupport::HashWithIndifferentAccess, @symbols.with_indifferent_access.stringify_keys
+    assert_equal @strings, @symbols.with_indifferent_access.stringify_keys
+    assert_equal @strings, @strings.with_indifferent_access.stringify_keys
+    assert_equal @strings, @mixed.with_indifferent_access.stringify_keys
+  end
+
+  def test_deep_stringify_keys_for_hash_with_indifferent_access
+    assert_instance_of ActiveSupport::HashWithIndifferentAccess, @nested_symbols.with_indifferent_access.deep_stringify_keys
+    assert_equal @nested_strings, @nested_symbols.with_indifferent_access.deep_stringify_keys
+    assert_equal @nested_strings, @nested_strings.with_indifferent_access.deep_stringify_keys
+    assert_equal @nested_strings, @nested_mixed.with_indifferent_access.deep_stringify_keys
+  end
+
+  def test_stringify_keys_bang_for_hash_with_indifferent_access
+    assert_instance_of ActiveSupport::HashWithIndifferentAccess, @symbols.with_indifferent_access.dup.stringify_keys!
+    assert_equal @strings, @symbols.with_indifferent_access.dup.stringify_keys!
+    assert_equal @strings, @strings.with_indifferent_access.dup.stringify_keys!
+    assert_equal @strings, @mixed.with_indifferent_access.dup.stringify_keys!
+  end
+
+  def test_deep_stringify_keys_bang_for_hash_with_indifferent_access
+    assert_instance_of ActiveSupport::HashWithIndifferentAccess, @nested_symbols.with_indifferent_access.dup.deep_stringify_keys!
+    assert_equal @nested_strings, @nested_symbols.with_indifferent_access.deep_dup.deep_stringify_keys!
+    assert_equal @nested_strings, @nested_strings.with_indifferent_access.deep_dup.deep_stringify_keys!
+    assert_equal @nested_strings, @nested_mixed.with_indifferent_access.deep_dup.deep_stringify_keys!
+  end
+
+  def test_nested_under_indifferent_access
+    foo = { "foo" => SubclassingHash.new.tap { |h| h["bar"] = "baz" } }.with_indifferent_access
+    assert_kind_of ActiveSupport::HashWithIndifferentAccess, foo["foo"]
+
+    foo = { "foo" => NonIndifferentHash.new.tap { |h| h["bar"] = "baz" } }.with_indifferent_access
+    assert_kind_of NonIndifferentHash, foo["foo"]
+
+    foo = { "foo" => IndifferentHash.new.tap { |h| h["bar"] = "baz" } }.with_indifferent_access
+    assert_kind_of IndifferentHash, foo["foo"]
+  end
+
+  def test_indifferent_assorted
+    @strings = @strings.with_indifferent_access
+    @symbols = @symbols.with_indifferent_access
+    @mixed   = @mixed.with_indifferent_access
+
+    assert_equal "a", @strings.__send__(:convert_key, :a)
+
+    assert_equal 1, @strings.fetch("a")
+    assert_equal 1, @strings.fetch(:a.to_s)
+    assert_equal 1, @strings.fetch(:a)
+
+    hashes = { :@strings => @strings, :@symbols => @symbols, :@mixed => @mixed }
+    method_map = { '[]': 1, fetch: 1, values_at: [1],
+                   has_key?: true, include?: true, key?: true,
+                   member?: true }
+
+    hashes.each do |name, hash|
+      method_map.sort_by(&:to_s).each do |meth, expected|
+        assert_equal(expected, hash.__send__(meth, "a"),
+                     "Calling #{name}.#{meth} 'a'")
+        assert_equal(expected, hash.__send__(meth, :a),
+                     "Calling #{name}.#{meth} :a")
+      end
+    end
+
+    assert_equal [1, 2], @strings.values_at("a", "b")
+    assert_equal [1, 2], @strings.values_at(:a, :b)
+    assert_equal [1, 2], @symbols.values_at("a", "b")
+    assert_equal [1, 2], @symbols.values_at(:a, :b)
+    assert_equal [1, 2], @mixed.values_at("a", "b")
+    assert_equal [1, 2], @mixed.values_at(:a, :b)
+  end
+
+  def test_indifferent_fetch_values
+    skip unless Hash.method_defined?(:fetch_values)
+
+    @mixed = @mixed.with_indifferent_access
+
+    assert_equal [1, 2], @mixed.fetch_values("a", "b")
+    assert_equal [1, 2], @mixed.fetch_values(:a, :b)
+    assert_equal [1, 2], @mixed.fetch_values(:a, "b")
+    assert_equal [1, "c"], @mixed.fetch_values(:a, :c) { |key| key }
+    assert_raise(KeyError) { @mixed.fetch_values(:a, :c) }
+  end
+
+  def test_indifferent_reading
+    hash = HashWithIndifferentAccess.new
+    hash["a"] = 1
+    hash["b"] = true
+    hash["c"] = false
+    hash["d"] = nil
+
+    assert_equal 1, hash[:a]
+    assert_equal true, hash[:b]
+    assert_equal false, hash[:c]
+    assert_nil hash[:d]
+    assert_nil hash[:e]
+  end
+
+  def test_indifferent_reading_with_nonnil_default
+    hash = HashWithIndifferentAccess.new(1)
+    hash["a"] = 1
+    hash["b"] = true
+    hash["c"] = false
+    hash["d"] = nil
+
+    assert_equal 1, hash[:a]
+    assert_equal true, hash[:b]
+    assert_equal false, hash[:c]
+    assert_nil hash[:d]
+    assert_equal 1, hash[:e]
+  end
+
+  def test_indifferent_writing
+    hash = HashWithIndifferentAccess.new
+    hash[:a] = 1
+    hash["b"] = 2
+    hash[3] = 3
+
+    assert_equal 1, hash["a"]
+    assert_equal 2, hash["b"]
+    assert_equal 1, hash[:a]
+    assert_equal 2, hash[:b]
+    assert_equal 3, hash[3]
+  end
+
+  def test_indifferent_update
+    hash = HashWithIndifferentAccess.new
+    hash[:a] = "a"
+    hash["b"] = "b"
+
+    updated_with_strings = hash.update(@strings)
+    updated_with_symbols = hash.update(@symbols)
+    updated_with_mixed = hash.update(@mixed)
+
+    assert_equal 1, updated_with_strings[:a]
+    assert_equal 1, updated_with_strings["a"]
+    assert_equal 2, updated_with_strings["b"]
+
+    assert_equal 1, updated_with_symbols[:a]
+    assert_equal 2, updated_with_symbols["b"]
+    assert_equal 2, updated_with_symbols[:b]
+
+    assert_equal 1, updated_with_mixed[:a]
+    assert_equal 2, updated_with_mixed["b"]
+
+    assert [updated_with_strings, updated_with_symbols, updated_with_mixed].all? { |h| h.keys.size == 2 }
+  end
+
+  def test_update_with_to_hash_conversion
+    hash = HashWithIndifferentAccess.new
+    hash.update HashByConversion.new(a: 1)
+    assert_equal 1, hash["a"]
+  end
+
+  def test_indifferent_merging
+    hash = HashWithIndifferentAccess.new
+    hash[:a] = "failure"
+    hash["b"] = "failure"
+
+    other = { "a" => 1, :b => 2 }
+
+    merged = hash.merge(other)
+
+    assert_equal HashWithIndifferentAccess, merged.class
+    assert_equal 1, merged[:a]
+    assert_equal 2, merged["b"]
+
+    hash.update(other)
+
+    assert_equal 1, hash[:a]
+    assert_equal 2, hash["b"]
+  end
+
+  def test_merge_with_to_hash_conversion
+    hash = HashWithIndifferentAccess.new
+    merged = hash.merge HashByConversion.new(a: 1)
+    assert_equal 1, merged["a"]
+  end
+
+  def test_indifferent_replace
+    hash = HashWithIndifferentAccess.new
+    hash[:a] = 42
+
+    replaced = hash.replace(b: 12)
+
+    assert hash.key?("b")
+    assert !hash.key?(:a)
+    assert_equal 12, hash[:b]
+    assert_same hash, replaced
+  end
+
+  def test_replace_with_to_hash_conversion
+    hash = HashWithIndifferentAccess.new
+    hash[:a] = 42
+
+    replaced = hash.replace(HashByConversion.new(b: 12))
+
+    assert hash.key?("b")
+    assert !hash.key?(:a)
+    assert_equal 12, hash[:b]
+    assert_same hash, replaced
+  end
+
+  def test_indifferent_merging_with_block
+    hash = HashWithIndifferentAccess.new
+    hash[:a] = 1
+    hash["b"] = 3
+
+    other = { "a" => 4, :b => 2, "c" => 10 }
+
+    merged = hash.merge(other) { |key, old, new| old > new ? old : new }
+
+    assert_equal HashWithIndifferentAccess, merged.class
+    assert_equal 4, merged[:a]
+    assert_equal 3, merged["b"]
+    assert_equal 10, merged[:c]
+
+    other_indifferent = HashWithIndifferentAccess.new("a" => 9, :b => 2)
+
+    merged = hash.merge(other_indifferent) { |key, old, new| old + new }
+
+    assert_equal HashWithIndifferentAccess, merged.class
+    assert_equal 10, merged[:a]
+    assert_equal 5, merged[:b]
+  end
+
+  def test_indifferent_reverse_merging
+    hash = HashWithIndifferentAccess.new key: :old_value
+    hash.reverse_merge! key: :new_value
+    assert_equal :old_value, hash[:key]
+
+    hash = HashWithIndifferentAccess.new("some" => "value", "other" => "value")
+    hash.reverse_merge!(some: "noclobber", another: "clobber")
+    assert_equal "value", hash[:some]
+    assert_equal "clobber", hash[:another]
+  end
+
+  def test_indifferent_with_defaults_aliases_reverse_merge
+    hash = HashWithIndifferentAccess.new key: :old_value
+    actual = hash.with_defaults key: :new_value
+    assert_equal :old_value, actual[:key]
+
+    hash = HashWithIndifferentAccess.new key: :old_value
+    hash.with_defaults! key: :new_value
+    assert_equal :old_value, hash[:key]
+  end
+
+  def test_indifferent_deleting
+    get_hash = proc { { a: "foo" }.with_indifferent_access }
+    hash = get_hash.call
+    assert_equal "foo", hash.delete(:a)
+    assert_nil hash.delete(:a)
+    hash = get_hash.call
+    assert_equal "foo", hash.delete("a")
+    assert_nil hash.delete("a")
+  end
+
+  def test_indifferent_select
+    hash = ActiveSupport::HashWithIndifferentAccess.new(@strings).select { |k, v| v == 1 }
+
+    assert_equal({ "a" => 1 }, hash)
+    assert_instance_of ActiveSupport::HashWithIndifferentAccess, hash
+  end
+
+  def test_indifferent_select_returns_enumerator
+    enum = ActiveSupport::HashWithIndifferentAccess.new(@strings).select
+    assert_instance_of Enumerator, enum
+  end
+
+  def test_indifferent_select_returns_a_hash_when_unchanged
+    hash = ActiveSupport::HashWithIndifferentAccess.new(@strings).select { |k, v| true }
+
+    assert_instance_of ActiveSupport::HashWithIndifferentAccess, hash
+  end
+
+  def test_indifferent_select_bang
+    indifferent_strings = ActiveSupport::HashWithIndifferentAccess.new(@strings)
+    indifferent_strings.select! { |k, v| v == 1 }
+
+    assert_equal({ "a" => 1 }, indifferent_strings)
+    assert_instance_of ActiveSupport::HashWithIndifferentAccess, indifferent_strings
+  end
+
+  def test_indifferent_reject
+    hash = ActiveSupport::HashWithIndifferentAccess.new(@strings).reject { |k, v| v != 1 }
+
+    assert_equal({ "a" => 1 }, hash)
+    assert_instance_of ActiveSupport::HashWithIndifferentAccess, hash
+  end
+
+  def test_indifferent_reject_returns_enumerator
+    enum = ActiveSupport::HashWithIndifferentAccess.new(@strings).reject
+    assert_instance_of Enumerator, enum
+  end
+
+  def test_indifferent_reject_bang
+    indifferent_strings = ActiveSupport::HashWithIndifferentAccess.new(@strings)
+    indifferent_strings.reject! { |k, v| v != 1 }
+
+    assert_equal({ "a" => 1 }, indifferent_strings)
+    assert_instance_of ActiveSupport::HashWithIndifferentAccess, indifferent_strings
+  end
+
+  def test_indifferent_transform_keys
+    hash = ActiveSupport::HashWithIndifferentAccess.new(@strings).transform_keys { |k| k * 2 }
+
+    assert_equal({ "aa" => 1, "bb" => 2 }, hash)
+    assert_instance_of ActiveSupport::HashWithIndifferentAccess, hash
+  end
+
+  def test_indifferent_transform_keys_bang
+    indifferent_strings = ActiveSupport::HashWithIndifferentAccess.new(@strings)
+    indifferent_strings.transform_keys! { |k| k * 2 }
+
+    assert_equal({ "aa" => 1, "bb" => 2 }, indifferent_strings)
+    assert_instance_of ActiveSupport::HashWithIndifferentAccess, indifferent_strings
+  end
+
+  def test_indifferent_transform_values
+    hash = ActiveSupport::HashWithIndifferentAccess.new(@strings).transform_values { |v| v * 2 }
+
+    assert_equal({ "a" => 2, "b" => 4 }, hash)
+    assert_instance_of ActiveSupport::HashWithIndifferentAccess, hash
+  end
+
+  def test_indifferent_transform_values_bang
+    indifferent_strings = ActiveSupport::HashWithIndifferentAccess.new(@strings)
+    indifferent_strings.transform_values! { |v| v * 2 }
+
+    assert_equal({ "a" => 2, "b" => 4 }, indifferent_strings)
+    assert_instance_of ActiveSupport::HashWithIndifferentAccess, indifferent_strings
+  end
+
+  def test_indifferent_compact
+    hash_contain_nil_value = @strings.merge("z" => nil)
+    hash = ActiveSupport::HashWithIndifferentAccess.new(hash_contain_nil_value)
+    compacted_hash = hash.compact
+
+    assert_equal(@strings, compacted_hash)
+    assert_equal(hash_contain_nil_value, hash)
+    assert_instance_of ActiveSupport::HashWithIndifferentAccess, compacted_hash
+
+    empty_hash = ActiveSupport::HashWithIndifferentAccess.new
+    compacted_hash = empty_hash.compact
+
+    assert_equal compacted_hash, empty_hash
+
+    non_empty_hash = ActiveSupport::HashWithIndifferentAccess.new(foo: :bar)
+    compacted_hash = non_empty_hash.compact
+
+    assert_equal compacted_hash, non_empty_hash
+  end
+
+  def test_indifferent_to_hash
+    # Should convert to a Hash with String keys.
+    assert_equal @strings, @mixed.with_indifferent_access.to_hash
+
+    # Should preserve the default value.
+    mixed_with_default = @mixed.dup
+    mixed_with_default.default = "1234"
+    roundtrip = mixed_with_default.with_indifferent_access.to_hash
+    assert_equal @strings, roundtrip
+    assert_equal "1234", roundtrip.default
+
+    # Ensure nested hashes are not HashWithIndiffereneAccess
+    new_to_hash = @nested_mixed.with_indifferent_access.to_hash
+    assert_not new_to_hash.instance_of?(HashWithIndifferentAccess)
+    assert_not new_to_hash["a"].instance_of?(HashWithIndifferentAccess)
+    assert_not new_to_hash["a"]["b"].instance_of?(HashWithIndifferentAccess)
+  end
+
+  def test_lookup_returns_the_same_object_that_is_stored_in_hash_indifferent_access
+    hash = HashWithIndifferentAccess.new { |h, k| h[k] = [] }
+    hash[:a] << 1
+
+    assert_equal [1], hash[:a]
+  end
+
+  def test_with_indifferent_access_has_no_side_effects_on_existing_hash
+    hash = { content: [{ :foo => :bar, "bar" => "baz" }] }
+    hash.with_indifferent_access
+
+    assert_equal [:foo, "bar"], hash[:content].first.keys
+  end
+
+  def test_indifferent_hash_with_array_of_hashes
+    hash = { "urls" => { "url" => [ { "address" => "1" }, { "address" => "2" } ] } }.with_indifferent_access
+    assert_equal "1", hash[:urls][:url].first[:address]
+
+    hash = hash.to_hash
+    assert_not hash.instance_of?(HashWithIndifferentAccess)
+    assert_not hash["urls"].instance_of?(HashWithIndifferentAccess)
+    assert_not hash["urls"]["url"].first.instance_of?(HashWithIndifferentAccess)
+  end
+
+  def test_should_preserve_array_subclass_when_value_is_array
+    array = SubclassingArray.new
+    array << { "address" => "1" }
+    hash = { "urls" => { "url" => array } }.with_indifferent_access
+    assert_equal SubclassingArray, hash[:urls][:url].class
+  end
+
+  def test_should_preserve_array_class_when_hash_value_is_frozen_array
+    array = SubclassingArray.new
+    array << { "address" => "1" }
+    hash = { "urls" => { "url" => array.freeze } }.with_indifferent_access
+    assert_equal SubclassingArray, hash[:urls][:url].class
+  end
+
+  def test_stringify_and_symbolize_keys_on_indifferent_preserves_hash
+    h = HashWithIndifferentAccess.new
+    h[:first] = 1
+    h = h.stringify_keys
+    assert_equal 1, h["first"]
+    h = HashWithIndifferentAccess.new
+    h["first"] = 1
+    h = h.symbolize_keys
+    assert_equal 1, h[:first]
+  end
+
+  def test_deep_stringify_and_deep_symbolize_keys_on_indifferent_preserves_hash
+    h = HashWithIndifferentAccess.new
+    h[:first] = 1
+    h = h.deep_stringify_keys
+    assert_equal 1, h["first"]
+    h = HashWithIndifferentAccess.new
+    h["first"] = 1
+    h = h.deep_symbolize_keys
+    assert_equal 1, h[:first]
+  end
+
+  def test_to_options_on_indifferent_preserves_hash
+    h = HashWithIndifferentAccess.new
+    h["first"] = 1
+    h.to_options!
+    assert_equal 1, h["first"]
+  end
+
+  def test_to_options_on_indifferent_preserves_works_as_hash_with_dup
+    h = HashWithIndifferentAccess.new(a: { b: "b" })
+    dup = h.dup
+
+    dup[:a][:c] = "c"
+    assert_equal "c", h[:a][:c]
+  end
+
+  def test_indifferent_sub_hashes
+    h = { "user" => { "id" => 5 } }.with_indifferent_access
+    ["user", :user].each { |user| [:id, "id"].each { |id| assert_equal 5, h[user][id], "h[#{user.inspect}][#{id.inspect}] should be 5" } }
+
+    h = { user: { id: 5 } }.with_indifferent_access
+    ["user", :user].each { |user| [:id, "id"].each { |id| assert_equal 5, h[user][id], "h[#{user.inspect}][#{id.inspect}] should be 5" } }
+  end
+
+  def test_indifferent_duplication
+    # Should preserve default value
+    h = HashWithIndifferentAccess.new
+    h.default = "1234"
+    assert_equal h.default, h.dup.default
+
+    # Should preserve class for subclasses
+    h = IndifferentHash.new
+    assert_equal h.class, h.dup.class
+  end
+
+  def test_nested_dig_indifferent_access
+    skip if RUBY_VERSION < "2.3.0"
+    data = { "this" => { "views" => 1234 } }.with_indifferent_access
+    assert_equal 1234, data.dig(:this, :views)
+  end
+
+  def test_argless_default_with_existing_nil_key
+    h = Hash.new(:default).merge(nil => "defined").with_indifferent_access
+
+    assert_equal :default, h.default
+  end
+
+  def test_default_with_argument
+    h = Hash.new { 5 }.merge(1 => 2).with_indifferent_access
+
+    assert_equal 5, h.default(1)
+  end
+
+  def test_default_proc
+    h = ActiveSupport::HashWithIndifferentAccess.new { |hash, key| key }
+
+    assert_nil h.default
+    assert_equal "foo", h.default("foo")
+    assert_equal "foo", h.default(:foo)
+  end
+
+  def test_double_conversion_with_nil_key
+    h = { nil => "defined" }.with_indifferent_access.with_indifferent_access
+
+    assert_nil h[:undefined_key]
+  end
+
+  def test_assorted_keys_not_stringified
+    original = { Object.new => 2, 1 => 2, [] => true }
+    indiff = original.with_indifferent_access
+    assert(!indiff.keys.any? { |k| k.kind_of? String }, "A key was converted to a string!")
+  end
+
+  def test_deep_merge_on_indifferent_access
+    hash_1 = HashWithIndifferentAccess.new(a: "a", b: "b", c: { c1: "c1", c2: "c2", c3: { d1: "d1" } })
+    hash_2 = HashWithIndifferentAccess.new(a: 1, c: { c1: 2, c3: { d2: "d2" } })
+    hash_3 = { a: 1, c: { c1: 2, c3: { d2: "d2" } } }
+    expected = { "a" => 1, "b" => "b", "c" => { "c1" => 2, "c2" => "c2", "c3" => { "d1" => "d1", "d2" => "d2" } } }
+    assert_equal expected, hash_1.deep_merge(hash_2)
+    assert_equal expected, hash_1.deep_merge(hash_3)
+
+    hash_1.deep_merge!(hash_2)
+    assert_equal expected, hash_1
+  end
+
+  def test_store_on_indifferent_access
+    hash = HashWithIndifferentAccess.new
+    hash.store(:test1, 1)
+    hash.store("test1", 11)
+    hash[:test2] = 2
+    hash["test2"] = 22
+    expected = { "test1" => 11, "test2" => 22 }
+    assert_equal expected, hash
+  end
+
+  def test_constructor_on_indifferent_access
+    hash = HashWithIndifferentAccess[:foo, 1]
+    assert_equal 1, hash[:foo]
+    assert_equal 1, hash["foo"]
+    hash[:foo] = 3
+    assert_equal 3, hash[:foo]
+    assert_equal 3, hash["foo"]
+  end
+
+  def test_indifferent_slice
+    original = { a: "x", b: "y", c: 10 }.with_indifferent_access
+    expected = { a: "x", b: "y" }.with_indifferent_access
+
+    [["a", "b"], [:a, :b]].each do |keys|
+      # Should return a new hash with only the given keys.
+      assert_equal expected, original.slice(*keys), keys.inspect
+      assert_not_equal expected, original
+    end
+  end
+
+  def test_indifferent_slice_inplace
+    original = { a: "x", b: "y", c: 10 }.with_indifferent_access
+    expected = { c: 10 }.with_indifferent_access
+
+    [["a", "b"], [:a, :b]].each do |keys|
+      # Should replace the hash with only the given keys.
+      copy = original.dup
+      assert_equal expected, copy.slice!(*keys)
+    end
+  end
+
+  def test_indifferent_slice_access_with_symbols
+    original = { "login" => "bender", "password" => "shiny", "stuff" => "foo" }
+    original = original.with_indifferent_access
+
+    slice = original.slice(:login, :password)
+
+    assert_equal "bender", slice[:login]
+    assert_equal "bender", slice["login"]
+  end
+
+  def test_indifferent_extract
+    original = { :a => 1, "b" => 2, :c => 3, "d" => 4 }.with_indifferent_access
+    expected = { a: 1, b: 2 }.with_indifferent_access
+    remaining = { c: 3, d: 4 }.with_indifferent_access
+
+    [["a", "b"], [:a, :b]].each do |keys|
+      copy = original.dup
+      assert_equal expected, copy.extract!(*keys)
+      assert_equal remaining, copy
+    end
+  end
+
+  def test_new_with_to_hash_conversion
+    hash = HashWithIndifferentAccess.new(HashByConversion.new(a: 1))
+    assert hash.key?("a")
+    assert_equal 1, hash[:a]
+  end
+
+  def test_dup_with_default_proc
+    hash = HashWithIndifferentAccess.new
+    hash.default_proc = proc { |h, v| raise "walrus" }
+    assert_nothing_raised { hash.dup }
+  end
+
+  def test_dup_with_default_proc_sets_proc
+    hash = HashWithIndifferentAccess.new
+    hash.default_proc = proc { |h, k| k + 1 }
+    new_hash = hash.dup
+
+    assert_equal 3, new_hash[2]
+
+    new_hash.default = 2
+    assert_equal 2, new_hash[:non_existent]
+  end
+
+  def test_to_hash_with_raising_default_proc
+    hash = HashWithIndifferentAccess.new
+    hash.default_proc = proc { |h, k| raise "walrus" }
+
+    assert_nothing_raised { hash.to_hash }
+  end
+
+  def test_new_with_to_hash_conversion_copies_default
+    normal_hash = Hash.new(3)
+    normal_hash[:a] = 1
+
+    hash = HashWithIndifferentAccess.new(HashByConversion.new(normal_hash))
+    assert_equal 1, hash[:a]
+    assert_equal 3, hash[:b]
+  end
+
+  def test_new_with_to_hash_conversion_copies_default_proc
+    normal_hash = Hash.new { 1 + 2 }
+    normal_hash[:a] = 1
+
+    hash = HashWithIndifferentAccess.new(HashByConversion.new(normal_hash))
+    assert_equal 1, hash[:a]
+    assert_equal 3, hash[:b]
+  end
+
+  def test_inheriting_from_top_level_hash_with_indifferent_access_preserves_ancestors_chain
+    klass = Class.new(::HashWithIndifferentAccess)
+    assert_equal ActiveSupport::HashWithIndifferentAccess, klass.ancestors[1]
+  end
+
+  def test_inheriting_from_hash_with_indifferent_access_properly_dumps_ivars
+    klass = Class.new(::HashWithIndifferentAccess) do
+      def initialize(*)
+        @foo = "bar"
+        super
+      end
+    end
+
+    yaml_output = klass.new.to_yaml
+
+    # `hash-with-ivars` was introduced in 2.0.9 (https://git.io/vyUQW)
+    if Gem::Version.new(Psych::VERSION) >= Gem::Version.new("2.0.9")
+      assert_includes yaml_output, "hash-with-ivars"
+      assert_includes yaml_output, "@foo: bar"
+    else
+      assert_includes yaml_output, "hash"
+    end
+  end
+
+  def test_should_use_default_proc_for_unknown_key
+    hash_wia = HashWithIndifferentAccess.new { 1 + 2 }
+    assert_equal 3, hash_wia[:new_key]
+  end
+
+  def test_should_return_nil_if_no_key_is_supplied
+    hash_wia = HashWithIndifferentAccess.new { 1 + 2 }
+    assert_nil hash_wia.default
+  end
+
+  def test_should_use_default_value_for_unknown_key
+    hash_wia = HashWithIndifferentAccess.new(3)
+    assert_equal 3, hash_wia[:new_key]
+  end
+
+  def test_should_use_default_value_if_no_key_is_supplied
+    hash_wia = HashWithIndifferentAccess.new(3)
+    assert_equal 3, hash_wia.default
+  end
+
+  def test_should_nil_if_no_default_value_is_supplied
+    hash_wia = HashWithIndifferentAccess.new
+    assert_nil hash_wia.default
+  end
+
+  def test_should_return_dup_for_with_indifferent_access
+    hash_wia = HashWithIndifferentAccess.new
+    assert_equal hash_wia, hash_wia.with_indifferent_access
+    assert_not_same hash_wia, hash_wia.with_indifferent_access
+  end
+
+  def test_allows_setting_frozen_array_values_with_indifferent_access
+    value = [1, 2, 3].freeze
+    hash = HashWithIndifferentAccess.new
+    hash[:key] = value
+    assert_equal hash[:key], value
+  end
+
+  def test_should_copy_the_default_value_when_converting_to_hash_with_indifferent_access
+    hash = Hash.new(3)
+    hash_wia = hash.with_indifferent_access
+    assert_equal 3, hash_wia.default
+  end
+
+  def test_should_copy_the_default_proc_when_converting_to_hash_with_indifferent_access
+    hash = Hash.new do
+      2 + 1
+    end
+    assert_equal 3, hash[:foo]
+
+    hash_wia = hash.with_indifferent_access
+    assert_equal 3, hash_wia[:foo]
+    assert_equal 3, hash_wia[:bar]
+  end
+end
diff --git a/activesupport/test/i18n_test.rb b/activesupport/test/i18n_test.rb
index 3faa15e7fd..8ad9441f9d 100644
--- a/activesupport/test/i18n_test.rb
+++ b/activesupport/test/i18n_test.rb
@@ -1,6 +1,8 @@
-require 'abstract_unit'
-require 'active_support/time'
-require 'active_support/core_ext/array/conversions'
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "active_support/time"
+require "active_support/core_ext/array/conversions"
 
 class I18nTest < ActiveSupport::TestCase
   def setup
@@ -18,15 +20,15 @@ class I18nTest < ActiveSupport::TestCase
   end
 
   def test_date_localization_with_default_format
-    assert_equal @date.strftime("%Y-%m-%d"), I18n.localize(@date, :format => :default)
+    assert_equal @date.strftime("%Y-%m-%d"), I18n.localize(@date, format: :default)
   end
 
   def test_date_localization_with_short_format
-    assert_equal @date.strftime("%b %d"), I18n.localize(@date, :format => :short)
+    assert_equal @date.strftime("%b %d"), I18n.localize(@date, format: :short)
   end
 
   def test_date_localization_with_long_format
-    assert_equal @date.strftime("%B %d, %Y"), I18n.localize(@date, :format => :long)
+    assert_equal @date.strftime("%B %d, %Y"), I18n.localize(@date, format: :long)
   end
 
   def test_time_localization_should_use_default_format
@@ -34,15 +36,15 @@ class I18nTest < ActiveSupport::TestCase
   end
 
   def test_time_localization_with_default_format
-    assert_equal @time.strftime("%a, %d %b %Y %H:%M:%S %z"), I18n.localize(@time, :format => :default)
+    assert_equal @time.strftime("%a, %d %b %Y %H:%M:%S %z"), I18n.localize(@time, format: :default)
   end
 
   def test_time_localization_with_short_format
-    assert_equal @time.strftime("%d %b %H:%M"), I18n.localize(@time, :format => :short)
+    assert_equal @time.strftime("%d %b %H:%M"), I18n.localize(@time, format: :short)
   end
 
   def test_time_localization_with_long_format
-    assert_equal @time.strftime("%B %d, %Y %H:%M"), I18n.localize(@time, :format => :long)
+    assert_equal @time.strftime("%B %d, %Y %H:%M"), I18n.localize(@time, format: :long)
   end
 
   def test_day_names
@@ -66,39 +68,39 @@ class I18nTest < ActiveSupport::TestCase
   end
 
   def test_time_am
-    assert_equal 'am', I18n.translate(:'time.am')
+    assert_equal "am", I18n.translate(:'time.am')
   end
 
   def test_time_pm
-    assert_equal 'pm', I18n.translate(:'time.pm')
+    assert_equal "pm", I18n.translate(:'time.pm')
   end
 
   def test_words_connector
-    assert_equal ', ', I18n.translate(:'support.array.words_connector')
+    assert_equal ", ", I18n.translate(:'support.array.words_connector')
   end
 
   def test_two_words_connector
-    assert_equal ' and ', I18n.translate(:'support.array.two_words_connector')
+    assert_equal " and ", I18n.translate(:'support.array.two_words_connector')
   end
 
   def test_last_word_connector
-    assert_equal ', and ', I18n.translate(:'support.array.last_word_connector')
+    assert_equal ", and ", I18n.translate(:'support.array.last_word_connector')
   end
 
   def test_to_sentence
     default_two_words_connector = I18n.translate(:'support.array.two_words_connector')
     default_last_word_connector = I18n.translate(:'support.array.last_word_connector')
-    assert_equal 'a, b, and c', %w[a b c].to_sentence
-    I18n.backend.store_translations 'en', :support => { :array => { :two_words_connector => ' & ' } }
-    assert_equal 'a & b', %w[a b].to_sentence
-    I18n.backend.store_translations 'en', :support => { :array => { :last_word_connector => ' and ' } }
-    assert_equal 'a, b and c', %w[a b c].to_sentence
+    assert_equal "a, b, and c", %w[a b c].to_sentence
+    I18n.backend.store_translations "en", support: { array: { two_words_connector: " & " } }
+    assert_equal "a & b", %w[a b].to_sentence
+    I18n.backend.store_translations "en", support: { array: { last_word_connector: " and " } }
+    assert_equal "a, b and c", %w[a b c].to_sentence
   ensure
-    I18n.backend.store_translations 'en', :support => { :array => { :two_words_connector => default_two_words_connector } }
-    I18n.backend.store_translations 'en', :support => { :array => { :last_word_connector => default_last_word_connector } }
+    I18n.backend.store_translations "en", support: { array: { two_words_connector: default_two_words_connector } }
+    I18n.backend.store_translations "en", support: { array: { last_word_connector: default_last_word_connector } }
   end
 
   def test_to_sentence_with_empty_i18n_store
-    assert_equal 'a, b, and c', %w[a b c].to_sentence(locale: 'empty')
+    assert_equal "a, b, and c", %w[a b c].to_sentence(locale: "empty")
   end
 end
diff --git a/activesupport/test/inflector_test.rb b/activesupport/test/inflector_test.rb
index 06cd41c86d..0e3e576a70 100644
--- a/activesupport/test/inflector_test.rb
+++ b/activesupport/test/inflector_test.rb
@@ -1,8 +1,10 @@
-require 'abstract_unit'
-require 'active_support/inflector'
+# frozen_string_literal: true
 
-require 'inflector_test_cases'
-require 'constantize_test_cases'
+require "abstract_unit"
+require "active_support/inflector"
+
+require "inflector_test_cases"
+require "constantize_test_cases"
 
 class InflectorTest < ActiveSupport::TestCase
   include InflectorTestCases
@@ -31,6 +33,32 @@ class InflectorTest < ActiveSupport::TestCase
     assert_equal "", ActiveSupport::Inflector.pluralize("")
   end
 
+  test "uncountability of ascii word" do
+    word = "HTTP"
+    ActiveSupport::Inflector.inflections do |inflect|
+      inflect.uncountable word
+    end
+
+    assert_equal word, ActiveSupport::Inflector.pluralize(word)
+    assert_equal word, ActiveSupport::Inflector.singularize(word)
+    assert_equal ActiveSupport::Inflector.pluralize(word), ActiveSupport::Inflector.singularize(word)
+
+    ActiveSupport::Inflector.inflections.uncountables.pop
+  end
+
+  test "uncountability of non-ascii word" do
+    word = "猫"
+    ActiveSupport::Inflector.inflections do |inflect|
+      inflect.uncountable word
+    end
+
+    assert_equal word, ActiveSupport::Inflector.pluralize(word)
+    assert_equal word, ActiveSupport::Inflector.singularize(word)
+    assert_equal ActiveSupport::Inflector.pluralize(word), ActiveSupport::Inflector.singularize(word)
+
+    ActiveSupport::Inflector.inflections.uncountables.pop
+  end
+
   ActiveSupport::Inflector.inflections.uncountable.each do |word|
     define_method "test_uncountability_of_#{word}" do
       assert_equal word, ActiveSupport::Inflector.singularize(word)
@@ -80,7 +108,6 @@ class InflectorTest < ActiveSupport::TestCase
     end
   end
 
-
   def test_overwrite_previous_inflectors
     assert_equal("series", ActiveSupport::Inflector.singularize("series"))
     ActiveSupport::Inflector.inflections.singular "series", "serie"
@@ -94,6 +121,13 @@ class InflectorTest < ActiveSupport::TestCase
     end
   end
 
+  MixtureToTitleCaseWithKeepIdSuffix.each_with_index do |(before, titleized), index|
+    define_method "test_titleize_with_keep_id_suffix_mixture_to_title_case_#{index}" do
+      assert_equal(titleized, ActiveSupport::Inflector.titleize(before, keep_id_suffix: true),
+        "mixture to TitleCase with keep_id_suffix failed for #{before}")
+    end
+  end
+
   def test_camelize
     CamelToUnderscore.each do |camel, underscore|
       assert_equal(camel, ActiveSupport::Inflector.camelize(underscore))
@@ -101,11 +135,11 @@ class InflectorTest < ActiveSupport::TestCase
   end
 
   def test_camelize_with_lower_downcases_the_first_letter
-    assert_equal('capital', ActiveSupport::Inflector.camelize('Capital', false))
+    assert_equal("capital", ActiveSupport::Inflector.camelize("Capital", false))
   end
 
   def test_camelize_with_underscores
-    assert_equal("CamelCase", ActiveSupport::Inflector.camelize('Camel_Case'))
+    assert_equal("CamelCase", ActiveSupport::Inflector.camelize("Camel_Case"))
   end
 
   def test_acronyms
@@ -190,6 +224,12 @@ class InflectorTest < ActiveSupport::TestCase
     assert_equal("json_html_api", ActiveSupport::Inflector.underscore("JSONHTMLAPI"))
   end
 
+  def test_acronym_regexp_is_deprecated
+    assert_deprecated do
+      ActiveSupport::Inflector.inflections.acronym_regex
+    end
+  end
+
   def test_underscore
     CamelToUnderscore.each do |camel, underscore|
       assert_equal(underscore, ActiveSupport::Inflector.underscore(camel))
@@ -246,55 +286,27 @@ class InflectorTest < ActiveSupport::TestCase
     end
   end
 
-# FIXME: get following tests to pass on jruby, currently skipped
-#
-# Currently this fails because ActiveSupport::Multibyte::Unicode#tidy_bytes
-# required a specific Encoding::Converter(UTF-8 to UTF8-MAC) which unavailable on JRuby
-# causing our tests to error out.
-# related bug http://jira.codehaus.org/browse/JRUBY-7194
   def test_parameterize
-    jruby_skip "UTF-8 to UTF8-MAC Converter is unavailable"
     StringToParameterized.each do |some_string, parameterized_string|
       assert_equal(parameterized_string, ActiveSupport::Inflector.parameterize(some_string))
     end
   end
 
   def test_parameterize_and_normalize
-    jruby_skip "UTF-8 to UTF8-MAC Converter is unavailable"
     StringToParameterizedAndNormalized.each do |some_string, parameterized_string|
       assert_equal(parameterized_string, ActiveSupport::Inflector.parameterize(some_string))
     end
   end
 
   def test_parameterize_with_custom_separator
-    jruby_skip "UTF-8 to UTF8-MAC Converter is unavailable"
-    StringToParameterizeWithUnderscore.each do |some_string, parameterized_string|
-      assert_equal(parameterized_string, ActiveSupport::Inflector.parameterize(some_string, separator: '_'))
-    end
-  end
-
-  def test_parameterize_with_custom_separator_deprecated
-    jruby_skip "UTF-8 to UTF8-MAC Converter is unavailable"
     StringToParameterizeWithUnderscore.each do |some_string, parameterized_string|
-      assert_deprecated(/Passing the separator argument as a positional parameter is deprecated and will soon be removed. Use `separator: '_'` instead./i) do
-        assert_equal(parameterized_string, ActiveSupport::Inflector.parameterize(some_string, '_'))
-      end
+      assert_equal(parameterized_string, ActiveSupport::Inflector.parameterize(some_string, separator: "_"))
     end
   end
 
   def test_parameterize_with_multi_character_separator
-    jruby_skip "UTF-8 to UTF8-MAC Converter is unavailable"
     StringToParameterized.each do |some_string, parameterized_string|
-      assert_equal(parameterized_string.gsub('-', '__sep__'), ActiveSupport::Inflector.parameterize(some_string, separator: '__sep__'))
-    end
-  end
-
-  def test_parameterize_with_multi_character_separator_deprecated
-    jruby_skip "UTF-8 to UTF8-MAC Converter is unavailable"
-    StringToParameterized.each do |some_string, parameterized_string|
-      assert_deprecated(/Passing the separator argument as a positional parameter is deprecated and will soon be removed. Use `separator: '__sep__'` instead./i) do
-        assert_equal(parameterized_string.gsub('-', '__sep__'), ActiveSupport::Inflector.parameterize(some_string, '__sep__'))
-      end
+      assert_equal(parameterized_string.gsub("-", "__sep__"), ActiveSupport::Inflector.parameterize(some_string, separator: "__sep__"))
     end
   end
 
@@ -307,12 +319,12 @@ class InflectorTest < ActiveSupport::TestCase
 
   def test_classify_with_symbol
     assert_nothing_raised do
-      assert_equal 'FooBar', ActiveSupport::Inflector.classify(:foo_bars)
+      assert_equal "FooBar", ActiveSupport::Inflector.classify(:foo_bars)
     end
   end
 
   def test_classify_with_leading_schema_name
-    assert_equal 'FooBar', ActiveSupport::Inflector.classify('schema.foo_bar')
+    assert_equal "FooBar", ActiveSupport::Inflector.classify("schema.foo_bar")
   end
 
   def test_humanize
@@ -327,6 +339,12 @@ class InflectorTest < ActiveSupport::TestCase
     end
   end
 
+  def test_humanize_with_keep_id_suffix
+    UnderscoreToHumanWithKeepIdSuffix.each do |underscore, human|
+      assert_equal(human, ActiveSupport::Inflector.humanize(underscore, keep_id_suffix: true))
+    end
+  end
+
   def test_humanize_by_rule
     ActiveSupport::Inflector.inflections do |inflect|
       inflect.human(/_cnt$/i, '\1_count')
@@ -344,6 +362,19 @@ class InflectorTest < ActiveSupport::TestCase
     assert_equal("Col rpted bugs", ActiveSupport::Inflector.humanize("COL_rpted_bugs"))
   end
 
+  def test_humanize_with_acronyms
+    ActiveSupport::Inflector.inflections do |inflect|
+      inflect.acronym "LAX"
+      inflect.acronym "SFO"
+    end
+    assert_equal("LAX roundtrip to SFO", ActiveSupport::Inflector.humanize("LAX ROUNDTRIP TO SFO"))
+    assert_equal("LAX roundtrip to SFO", ActiveSupport::Inflector.humanize("LAX ROUNDTRIP TO SFO", capitalize: false))
+    assert_equal("LAX roundtrip to SFO", ActiveSupport::Inflector.humanize("lax roundtrip to sfo"))
+    assert_equal("LAX roundtrip to SFO", ActiveSupport::Inflector.humanize("lax roundtrip to sfo", capitalize: false))
+    assert_equal("LAX roundtrip to SFO", ActiveSupport::Inflector.humanize("Lax Roundtrip To Sfo"))
+    assert_equal("LAX roundtrip to SFO", ActiveSupport::Inflector.humanize("Lax Roundtrip To Sfo", capitalize: false))
+  end
+
   def test_constantize
     run_constantize_tests_on do |string|
       ActiveSupport::Inflector.constantize(string)
@@ -403,31 +434,38 @@ class InflectorTest < ActiveSupport::TestCase
 
   def test_inflector_locality
     ActiveSupport::Inflector.inflections(:es) do |inflect|
-      inflect.plural(/$/, 's')
-      inflect.plural(/z$/i, 'ces')
+      inflect.plural(/$/, "s")
+      inflect.plural(/z$/i, "ces")
+
+      inflect.singular(/s$/, "")
+      inflect.singular(/es$/, "")
 
-      inflect.singular(/s$/, '')
-      inflect.singular(/es$/, '')
+      inflect.irregular("el", "los")
 
-      inflect.irregular('el', 'los')
+      inflect.uncountable("agua")
     end
 
-    assert_equal('hijos', 'hijo'.pluralize(:es))
-    assert_equal('luces', 'luz'.pluralize(:es))
-    assert_equal('luzs', 'luz'.pluralize)
+    assert_equal("hijos", "hijo".pluralize(:es))
+    assert_equal("luces", "luz".pluralize(:es))
+    assert_equal("luzs", "luz".pluralize)
+
+    assert_equal("sociedad", "sociedades".singularize(:es))
+    assert_equal("sociedade", "sociedades".singularize)
 
-    assert_equal('sociedad', 'sociedades'.singularize(:es))
-    assert_equal('sociedade', 'sociedades'.singularize)
+    assert_equal("los", "el".pluralize(:es))
+    assert_equal("els", "el".pluralize)
 
-    assert_equal('los', 'el'.pluralize(:es))
-    assert_equal('els', 'el'.pluralize)
+    assert_equal("agua", "agua".pluralize(:es))
+    assert_equal("aguas", "agua".pluralize)
 
     ActiveSupport::Inflector.inflections(:es) { |inflect| inflect.clear }
 
     assert ActiveSupport::Inflector.inflections(:es).plurals.empty?
     assert ActiveSupport::Inflector.inflections(:es).singulars.empty?
+    assert ActiveSupport::Inflector.inflections(:es).uncountables.empty?
     assert !ActiveSupport::Inflector.inflections.plurals.empty?
     assert !ActiveSupport::Inflector.inflections.singulars.empty?
+    assert !ActiveSupport::Inflector.inflections.uncountables.empty?
   end
 
   def test_clear_all
@@ -435,7 +473,7 @@ class InflectorTest < ActiveSupport::TestCase
       # ensure any data is present
       inflect.plural(/(quiz)$/i, '\1zes')
       inflect.singular(/(database)s$/i, '\1')
-      inflect.uncountable('series')
+      inflect.uncountable("series")
       inflect.human("col_rpted_bugs", "Reported bugs")
 
       inflect.clear :all
@@ -452,7 +490,7 @@ class InflectorTest < ActiveSupport::TestCase
       # ensure any data is present
       inflect.plural(/(quiz)$/i, '\1zes')
       inflect.singular(/(database)s$/i, '\1')
-      inflect.uncountable('series')
+      inflect.uncountable("series")
       inflect.human("col_rpted_bugs", "Reported bugs")
 
       inflect.clear
@@ -526,12 +564,4 @@ class InflectorTest < ActiveSupport::TestCase
       end
     end
   end
-
-  def test_inflections_with_uncountable_words
-    ActiveSupport::Inflector.inflections do |inflect|
-      inflect.uncountable "HTTP"
-    end
-
-    assert_equal "HTTP", ActiveSupport::Inflector.pluralize("HTTP")
-  end
 end
diff --git a/activesupport/test/inflector_test_cases.rb b/activesupport/test/inflector_test_cases.rb
index c7dc1dadb6..689370cccf 100644
--- a/activesupport/test/inflector_test_cases.rb
+++ b/activesupport/test/inflector_test_cases.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module InflectorTestCases
   SingularToPlural = {
     "search"      => "searches",
@@ -128,10 +130,10 @@ module InflectorTestCases
   }
 
   SymbolToLowerCamel = {
-    :product                => 'product',
-    :special_guest          => 'specialGuest',
-    :application_controller => 'applicationController',
-    :area51_controller      => 'area51Controller'
+    product: "product",
+    special_guest: "specialGuest",
+    application_controller: "applicationController",
+    area51_controller: "area51Controller"
   }
 
   CamelToUnderscoreWithoutReverse = {
@@ -176,12 +178,12 @@ module InflectorTestCases
 
   StringToParameterizedPreserveCase = {
     "Donald E. Knuth"                     => "Donald-E-Knuth",
-    "Random text with *(bad)* characters" => "Random-text-with-bad-characters", 
-    "Allow_Under_Scores"                  => "Allow_Under_Scores", 
-    "Trailing bad characters!@#"          => "Trailing-bad-characters", 
-    "!@#Leading bad characters"           => "Leading-bad-characters", 
-    "Squeeze   separators"                => "Squeeze-separators", 
-    "Test with + sign"                    => "Test-with-sign", 
+    "Random text with *(bad)* characters" => "Random-text-with-bad-characters",
+    "Allow_Under_Scores"                  => "Allow_Under_Scores",
+    "Trailing bad characters!@#"          => "Trailing-bad-characters",
+    "!@#Leading bad characters"           => "Leading-bad-characters",
+    "Squeeze   separators"                => "Squeeze-separators",
+    "Test with + sign"                    => "Test-with-sign",
     "Test with malformed utf8 \xA9"       => "Test-with-malformed-utf8"
   }
 
@@ -199,11 +201,11 @@ module InflectorTestCases
   StringToParameterizePreserveCaseWithNoSeparator = {
     "Donald E. Knuth"                     => "DonaldEKnuth",
     "With-some-dashes"                    => "With-some-dashes",
-    "Random text with *(bad)* characters" => "Randomtextwithbadcharacters", 
-    "Trailing bad characters!@#"          => "Trailingbadcharacters", 
-    "!@#Leading bad characters"           => "Leadingbadcharacters", 
-    "Squeeze   separators"                => "Squeezeseparators", 
-    "Test with + sign"                    => "Testwithsign", 
+    "Random text with *(bad)* characters" => "Randomtextwithbadcharacters",
+    "Trailing bad characters!@#"          => "Trailingbadcharacters",
+    "!@#Leading bad characters"           => "Leadingbadcharacters",
+    "Squeeze   separators"                => "Squeezeseparators",
+    "Test with + sign"                    => "Testwithsign",
     "Test with malformed utf8 \xA9"       => "Testwithmalformedutf8"
   }
 
@@ -219,15 +221,15 @@ module InflectorTestCases
     "Test with malformed utf8 \251"       => "test_with_malformed_utf8"
   }
 
-  StringToParameterizePreserceCaseWithUnderscore = {
-    "Donald E. Knuth"                     => "Donald_E_Knuth", 
+  StringToParameterizePreserveCaseWithUnderscore = {
+    "Donald E. Knuth"                     => "Donald_E_Knuth",
     "Random text with *(bad)* characters" => "Random_text_with_bad_characters",
-    "With-some-dashes"                    => "With-some-dashes", 
-    "Allow_Under_Scores"                  => "Allow_Under_Scores", 
-    "Trailing bad characters!@#"          => "Trailing_bad_characters", 
-    "!@#Leading bad characters"           => "Leading_bad_characters", 
-    "Squeeze   separators"                => "Squeeze_separators", 
-    "Test with + sign"                    => "Test_with_sign", 
+    "With-some-dashes"                    => "With-some-dashes",
+    "Allow_Under_Scores"                  => "Allow_Under_Scores",
+    "Trailing bad characters!@#"          => "Trailing_bad_characters",
+    "!@#Leading bad characters"           => "Leading_bad_characters",
+    "Squeeze   separators"                => "Squeeze_separators",
+    "Test with + sign"                    => "Test_with_sign",
     "Test with malformed utf8 \xA9"       => "Test_with_malformed_utf8"
   }
 
@@ -237,15 +239,24 @@ module InflectorTestCases
     "Ops\331"                             => "opsu",
     "Ærøskøbing"                          => "aeroskobing",
     "Aßlar"                               => "asslar",
-    "Japanese: 日本語"                    => "japanese"
+    "Japanese: 日本語" => "japanese"
   }
 
   UnderscoreToHuman = {
-    'employee_salary' => 'Employee salary',
-    'employee_id'     => 'Employee',
-    'underground'     => 'Underground',
-    '_id'             => 'Id',
-    '_external_id'    => 'External'
+    "employee_salary" => "Employee salary",
+    "employee_id"     => "Employee",
+    "underground"     => "Underground",
+    "_id"             => "Id",
+    "_external_id"    => "External"
+  }
+
+  UnderscoreToHumanWithKeepIdSuffix = {
+    "this_is_a_string_ending_with_id" => "This is a string ending with id",
+    "employee_id"                => "Employee id",
+    "employee_id_something_else" => "Employee id something else",
+    "underground"               => "Underground",
+    "_id"                       => "Id",
+    "_external_id"              => "External id"
   }
 
   UnderscoreToHumanWithoutCapitalize = {
@@ -254,23 +265,30 @@ module InflectorTestCases
     "underground"     => "underground"
   }
 
+  MixtureToTitleCaseWithKeepIdSuffix = {
+    "this_is_a_string_ending_with_id" => "This Is A String Ending With Id",
+    "EmployeeId"                      => "Employee Id",
+    "Author Id"                       => "Author Id"
+  }
+
   MixtureToTitleCase = {
-    'active_record'         => 'Active Record',
-    'ActiveRecord'          => 'Active Record',
-    'action web service'    => 'Action Web Service',
-    'Action Web Service'    => 'Action Web Service',
-    'Action web service'    => 'Action Web Service',
-    'actionwebservice'      => 'Actionwebservice',
-    'Actionwebservice'      => 'Actionwebservice',
+    "active_record"         => "Active Record",
+    "ActiveRecord"          => "Active Record",
+    "action web service"    => "Action Web Service",
+    "Action Web Service"    => "Action Web Service",
+    "Action web service"    => "Action Web Service",
+    "actionwebservice"      => "Actionwebservice",
+    "Actionwebservice"      => "Actionwebservice",
     "david's code"          => "David's Code",
     "David's code"          => "David's Code",
     "david's Code"          => "David's Code",
     "sgt. pepper's"         => "Sgt. Pepper's",
     "i've just seen a face" => "I've Just Seen A Face",
     "maybe you'll be there" => "Maybe You'll Be There",
-    "¿por qué?"             => '¿Por Qué?',
+    "¿por qué?"             => "¿Por Qué?",
     "Fred’s"                => "Fred’s",
     "Fred`s"                => "Fred`s",
+    "this was 'fake news'"  => "This Was 'Fake News'",
     ActiveSupport::SafeBuffer.new("confirmation num") => "Confirmation Num"
   }
 
@@ -345,13 +363,13 @@ module InflectorTestCases
   }
 
   Irregularities = {
-    'person' => 'people',
-    'man'    => 'men',
-    'child'  => 'children',
-    'sex'    => 'sexes',
-    'move'   => 'moves',
-    'cow'    => 'kine', # Test inflections with different starting letters
-    'zombie' => 'zombies',
-    'genus'  => 'genera'
+    "person" => "people",
+    "man"    => "men",
+    "child"  => "children",
+    "sex"    => "sexes",
+    "move"   => "moves",
+    "cow"    => "kine", # Test inflections with different starting letters
+    "zombie" => "zombies",
+    "genus"  => "genera"
   }
 end
diff --git a/activesupport/test/json/decoding_test.rb b/activesupport/test/json/decoding_test.rb
index f2fc456f4b..8d9587f248 100644
--- a/activesupport/test/json/decoding_test.rb
+++ b/activesupport/test/json/decoding_test.rb
@@ -1,8 +1,13 @@
-require 'abstract_unit'
-require 'active_support/json'
-require 'active_support/time'
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "active_support/json"
+require "active_support/time"
+require "time_zone_test_helpers"
 
 class TestJSONDecoding < ActiveSupport::TestCase
+  include TimeZoneTestHelpers
+
   class Foo
     def self.json_create(object)
       "Foo"
@@ -10,72 +15,80 @@ class TestJSONDecoding < ActiveSupport::TestCase
   end
 
   TESTS = {
-    %q({"returnTo":{"\/categories":"\/"}})        => {"returnTo" => {"/categories" => "/"}},
-    %q({"return\\"To\\":":{"\/categories":"\/"}}) => {"return\"To\":" => {"/categories" => "/"}},
-    %q({"returnTo":{"\/categories":1}})          => {"returnTo" => {"/categories" => 1}},
-    %({"returnTo":[1,"a"]})                    => {"returnTo" => [1, "a"]},
-    %({"returnTo":[1,"\\"a\\",", "b"]})        => {"returnTo" => [1, "\"a\",", "b"]},
-    %({"a": "'", "b": "5,000"})                  => {"a" => "'", "b" => "5,000"},
-    %({"a": "a's, b's and c's", "b": "5,000"})   => {"a" => "a's, b's and c's", "b" => "5,000"},
+    %q({"returnTo":{"\/categories":"\/"}})        => { "returnTo" => { "/categories" => "/" } },
+    %q({"return\\"To\\":":{"\/categories":"\/"}}) => { "return\"To\":" => { "/categories" => "/" } },
+    %q({"returnTo":{"\/categories":1}}) => { "returnTo" => { "/categories" => 1 } },
+    %({"returnTo":[1,"a"]})                    => { "returnTo" => [1, "a"] },
+    %({"returnTo":[1,"\\"a\\",", "b"]})        => { "returnTo" => [1, "\"a\",", "b"] },
+    %({"a": "'", "b": "5,000"})                  => { "a" => "'", "b" => "5,000" },
+    %({"a": "a's, b's and c's", "b": "5,000"})   => { "a" => "a's, b's and c's", "b" => "5,000" },
     # multibyte
-    %({"matzue": "松江", "asakusa": "浅草"}) => {"matzue" => "松江", "asakusa" => "浅草"},
-    %({"a": "2007-01-01"})                       => {'a' => Date.new(2007, 1, 1)},
-    %({"a": "2007-01-01 01:12:34 Z"})            => {'a' => Time.utc(2007, 1, 1, 1, 12, 34)},
+    %({"matzue": "松江", "asakusa": "浅草"}) => { "matzue" => "松江", "asakusa" => "浅草" },
+    %({"a": "2007-01-01"})                       => { "a" => Date.new(2007, 1, 1) },
+    %({"a": "2007-01-01 01:12:34 Z"})            => { "a" => Time.utc(2007, 1, 1, 1, 12, 34) },
     %(["2007-01-01 01:12:34 Z"])                 => [Time.utc(2007, 1, 1, 1, 12, 34)],
     %(["2007-01-01 01:12:34 Z", "2007-01-01 01:12:35 Z"]) => [Time.utc(2007, 1, 1, 1, 12, 34), Time.utc(2007, 1, 1, 1, 12, 35)],
     # no time zone
-    %({"a": "2007-01-01 01:12:34"})              => {'a' => "2007-01-01 01:12:34"},
+    %({"a": "2007-01-01 01:12:34"})              => { "a" => Time.new(2007, 1, 1, 1, 12, 34, "-05:00") },
     # invalid date
-    %({"a": "1089-10-40"})                       => {'a' => "1089-10-40"},
+    %({"a": "1089-10-40"})                       => { "a" => "1089-10-40" },
     # xmlschema date notation
-    %({"a": "2009-08-10T19:01:02Z"})             => {'a' => Time.utc(2009, 8, 10, 19, 1, 2)},
-    %({"a": "2009-08-10T19:01:02+02:00"})        => {'a' => Time.utc(2009, 8, 10, 17, 1, 2)},
-    %({"a": "2009-08-10T19:01:02-05:00"})        => {'a' => Time.utc(2009, 8, 11, 00, 1, 2)},
+    %({"a": "2009-08-10T19:01:02"})              => { "a" => Time.new(2009, 8, 10, 19, 1, 2, "-04:00") },
+    %({"a": "2009-08-10T19:01:02Z"})             => { "a" => Time.utc(2009, 8, 10, 19, 1, 2) },
+    %({"a": "2009-08-10T19:01:02+02:00"})        => { "a" => Time.utc(2009, 8, 10, 17, 1, 2) },
+    %({"a": "2009-08-10T19:01:02-05:00"})        => { "a" => Time.utc(2009, 8, 11, 00, 1, 2) },
     # needs to be *exact*
-    %({"a": " 2007-01-01 01:12:34 Z "})          => {'a' => " 2007-01-01 01:12:34 Z "},
-    %({"a": "2007-01-01 : it's your birthday"})  => {'a' => "2007-01-01 : it's your birthday"},
+    %({"a": " 2007-01-01 01:12:34 Z "})          => { "a" => " 2007-01-01 01:12:34 Z " },
+    %({"a": "2007-01-01 : it's your birthday"})  => { "a" => "2007-01-01 : it's your birthday" },
     %([])    => [],
     %({})    => {},
-    %({"a":1})     => {"a" => 1},
-    %({"a": ""})    => {"a" => ""},
-    %({"a":"\\""}) => {"a" => "\""},
-    %({"a": null})  => {"a" => nil},
-    %({"a": true})  => {"a" => true},
-    %({"a": false}) => {"a" => false},
-    %q({"bad":"\\\\","trailing":""}) => {"bad" => "\\", "trailing" => ""},
-    %q({"a": "http:\/\/test.host\/posts\/1"}) => {"a" => "http://test.host/posts/1"},
-    %q({"a": "\u003cunicode\u0020escape\u003e"}) => {"a" => "<unicode escape>"},
-    %q({"a": "\\\\u0020skip double backslashes"}) => {"a" => "\\u0020skip double backslashes"},
-    %q({"a": "\u003cbr /\u003e"}) => {'a' => "<br />"},
-    %q({"b":["\u003ci\u003e","\u003cb\u003e","\u003cu\u003e"]}) => {'b' => ["<i>","<b>","<u>"]},
+    %({"a":1}) => { "a" => 1 },
+    %({"a": ""}) => { "a" => "" },
+    %({"a":"\\""}) => { "a" => "\"" },
+    %({"a": null})  => { "a" => nil },
+    %({"a": true})  => { "a" => true },
+    %({"a": false}) => { "a" => false },
+    '{"bad":"\\\\","trailing":""}' => { "bad" => "\\", "trailing" => "" },
+    %q({"a": "http:\/\/test.host\/posts\/1"}) => { "a" => "http://test.host/posts/1" },
+    %q({"a": "\u003cunicode\u0020escape\u003e"}) => { "a" => "<unicode escape>" },
+    '{"a": "\\\\u0020skip double backslashes"}' => { "a" => "\\u0020skip double backslashes" },
+    %q({"a": "\u003cbr /\u003e"}) => { "a" => "<br />" },
+    %q({"b":["\u003ci\u003e","\u003cb\u003e","\u003cu\u003e"]}) => { "b" => ["<i>", "<b>", "<u>"] },
     # test combination of dates and escaped or unicode encoded data in arrays
     %q([{"d":"1970-01-01", "s":"\u0020escape"},{"d":"1970-01-01", "s":"\u0020escape"}]) =>
-      [{'d' => Date.new(1970, 1, 1), 's' => ' escape'},{'d' => Date.new(1970, 1, 1), 's' => ' escape'}],
+      [{ "d" => Date.new(1970, 1, 1), "s" => " escape" }, { "d" => Date.new(1970, 1, 1), "s" => " escape" }],
     %q([{"d":"1970-01-01","s":"http:\/\/example.com"},{"d":"1970-01-01","s":"http:\/\/example.com"}]) =>
-      [{'d' => Date.new(1970, 1, 1), 's' => 'http://example.com'},
-       {'d' => Date.new(1970, 1, 1), 's' => 'http://example.com'}],
+      [{ "d" => Date.new(1970, 1, 1), "s" => "http://example.com" },
+       { "d" => Date.new(1970, 1, 1), "s" => "http://example.com" }],
     # tests escaping of "\n" char with Yaml backend
-    %q({"a":"\n"})  => {"a"=>"\n"},
-    %q({"a":"\u000a"}) => {"a"=>"\n"},
-    %q({"a":"Line1\u000aLine2"}) => {"a"=>"Line1\nLine2"},
+    %q({"a":"\n"}) => { "a" => "\n" },
+    %q({"a":"\u000a"}) => { "a" => "\n" },
+    %q({"a":"Line1\u000aLine2"}) => { "a" => "Line1\nLine2" },
     # prevent json unmarshalling
-    %q({"json_class":"TestJSONDecoding::Foo"}) => {"json_class"=>"TestJSONDecoding::Foo"},
+    '{"json_class":"TestJSONDecoding::Foo"}' => { "json_class" => "TestJSONDecoding::Foo" },
     # json "fragments" - these are invalid JSON, but ActionPack relies on this
-    %q("a string") => "a string",
-    %q(1.1) => 1.1,
-    %q(1) => 1,
-    %q(-1) => -1,
-    %q(true) => true,
-    %q(false) => false,
-    %q(null) => nil
+    '"a string"' => "a string",
+    "1.1" => 1.1,
+    "1" => 1,
+    "-1" => -1,
+    "true" => true,
+    "false" => false,
+    "null" => nil
   }
 
   TESTS.each_with_index do |(json, expected), index|
+    fail_message = "JSON decoding failed for #{json}"
+
     test "json decodes #{index}" do
-      with_parse_json_times(true) do
-        silence_warnings do
-          assert_equal expected, ActiveSupport::JSON.decode(json), "JSON decoding \
-          failed for #{json}"
+      with_tz_default "Eastern Time (US & Canada)" do
+        with_parse_json_times(true) do
+          silence_warnings do
+            if expected.nil?
+              assert_nil ActiveSupport::JSON.decode(json), fail_message
+            else
+              assert_equal expected, ActiveSupport::JSON.decode(json), fail_message
+            end
+          end
         end
       end
     end
@@ -83,7 +96,7 @@ class TestJSONDecoding < ActiveSupport::TestCase
 
   test "json decodes time json with time parsing disabled" do
     with_parse_json_times(false) do
-      expected = {"a" => "2007-01-01 01:12:34 Z"}
+      expected = { "a" => "2007-01-01 01:12:34 Z" }
       assert_equal expected, ActiveSupport::JSON.decode(%({"a": "2007-01-01 01:12:34 Z"}))
     end
   end
@@ -101,12 +114,11 @@ class TestJSONDecoding < ActiveSupport::TestCase
 
   private
 
-  def with_parse_json_times(value)
-    old_value = ActiveSupport.parse_json_times
-    ActiveSupport.parse_json_times = value
-    yield
-  ensure
-    ActiveSupport.parse_json_times = old_value
-  end
+    def with_parse_json_times(value)
+      old_value = ActiveSupport.parse_json_times
+      ActiveSupport.parse_json_times = value
+      yield
+    ensure
+      ActiveSupport.parse_json_times = old_value
+    end
 end
-
diff --git a/activesupport/test/json/encoding_test.rb b/activesupport/test/json/encoding_test.rb
index 5fc2e16336..340a2abf75 100644
--- a/activesupport/test/json/encoding_test.rb
+++ b/activesupport/test/json/encoding_test.rb
@@ -1,17 +1,23 @@
-require 'securerandom'
-require 'abstract_unit'
-require 'active_support/core_ext/string/inflections'
-require 'active_support/json'
-require 'active_support/time'
-require 'time_zone_test_helpers'
-require 'json/encoding_test_cases'
+# frozen_string_literal: true
+
+require "securerandom"
+require "abstract_unit"
+require "active_support/core_ext/string/inflections"
+require "active_support/core_ext/regexp"
+require "active_support/json"
+require "active_support/time"
+require "time_zone_test_helpers"
+require "json/encoding_test_cases"
 
 class TestJSONEncoding < ActiveSupport::TestCase
   include TimeZoneTestHelpers
 
   def sorted_json(json)
-    return json unless json =~ /^\{.*\}$/
-    '{' + json[1..-2].split(',').sort.join(',') + '}'
+    if json.start_with?("{") && json.end_with?("}")
+      "{" + json[1..-2].split(",").sort.join(",") + "}"
+    else
+      json
+    end
   end
 
   JSONTest::EncodingTestCases.constants.each do |class_tests|
@@ -19,8 +25,10 @@ class TestJSONEncoding < ActiveSupport::TestCase
       begin
         prev = ActiveSupport.use_standard_json_time_format
 
-        ActiveSupport.escape_html_entities_in_json  = class_tests !~ /^Standard/
-        ActiveSupport.use_standard_json_time_format = class_tests =~ /^Standard/
+        standard_class_tests = /Standard/.match?(class_tests)
+
+        ActiveSupport.escape_html_entities_in_json  = !standard_class_tests
+        ActiveSupport.use_standard_json_time_format = standard_class_tests
         JSONTest::EncodingTestCases.const_get(class_tests).each do |pair|
           assert_equal pair.last, sorted_json(ActiveSupport::JSON.encode(pair.first))
         end
@@ -41,12 +49,12 @@ class TestJSONEncoding < ActiveSupport::TestCase
   end
 
   def test_hash_encoding
-    assert_equal %({\"a\":\"b\"}), ActiveSupport::JSON.encode(:a => :b)
-    assert_equal %({\"a\":1}), ActiveSupport::JSON.encode('a' => 1)
-    assert_equal %({\"a\":[1,2]}), ActiveSupport::JSON.encode('a' => [1,2])
+    assert_equal %({\"a\":\"b\"}), ActiveSupport::JSON.encode(a: :b)
+    assert_equal %({\"a\":1}), ActiveSupport::JSON.encode("a" => 1)
+    assert_equal %({\"a\":[1,2]}), ActiveSupport::JSON.encode("a" => [1, 2])
     assert_equal %({"1":2}), ActiveSupport::JSON.encode(1 => 2)
 
-    assert_equal %({\"a\":\"b\",\"c\":\"d\"}), sorted_json(ActiveSupport::JSON.encode(:a => :b, :c => :d))
+    assert_equal %({\"a\":\"b\",\"c\":\"d\"}), sorted_json(ActiveSupport::JSON.encode(a: :b, c: :d))
   end
 
   def test_hash_keys_encoding
@@ -57,24 +65,24 @@ class TestJSONEncoding < ActiveSupport::TestCase
   end
 
   def test_utf8_string_encoded_properly
-    result = ActiveSupport::JSON.encode('€2.99')
+    result = ActiveSupport::JSON.encode("€2.99")
     assert_equal '"€2.99"', result
     assert_equal(Encoding::UTF_8, result.encoding)
 
-    result = ActiveSupport::JSON.encode('✎☺')
+    result = ActiveSupport::JSON.encode("✎☺")
     assert_equal '"✎☺"', result
     assert_equal(Encoding::UTF_8, result.encoding)
   end
 
   def test_non_utf8_string_transcodes
-    s = '二'.encode('Shift_JIS')
+    s = "二".encode("Shift_JIS")
     result = ActiveSupport::JSON.encode(s)
     assert_equal '"二"', result
     assert_equal Encoding::UTF_8, result.encoding
   end
 
   def test_wide_utf8_chars
-    w = '𠜎'
+    w = "𠜎"
     result = ActiveSupport::JSON.encode(w)
     assert_equal '"𠜎"', result
   end
@@ -83,33 +91,33 @@ class TestJSONEncoding < ActiveSupport::TestCase
     hash = { string: "𐒑" }
     json = ActiveSupport::JSON.encode(hash)
     decoded_hash = ActiveSupport::JSON.decode(json)
-    assert_equal "𐒑", decoded_hash['string']
+    assert_equal "𐒑", decoded_hash["string"]
   end
 
   def test_hash_key_identifiers_are_always_quoted
-    values = {0 => 0, 1 => 1, :_ => :_, "$" => "$", "a" => "a", :A => :A, :A0 => :A0, "A0B" => "A0B"}
+    values = { 0 => 0, 1 => 1, :_ => :_, "$" => "$", "a" => "a", :A => :A, :A0 => :A0, "A0B" => "A0B" }
     assert_equal %w( "$" "A" "A0" "A0B" "_" "a" "0" "1" ).sort, object_keys(ActiveSupport::JSON.encode(values))
   end
 
   def test_hash_should_allow_key_filtering_with_only
-    assert_equal %({"a":1}), ActiveSupport::JSON.encode({'a' => 1, :b => 2, :c => 3}, :only => 'a')
+    assert_equal %({"a":1}), ActiveSupport::JSON.encode({ "a" => 1, :b => 2, :c => 3 }, { only: "a" })
   end
 
   def test_hash_should_allow_key_filtering_with_except
-    assert_equal %({"b":2}), ActiveSupport::JSON.encode({'foo' => 'bar', :b => 2, :c => 3}, :except => ['foo', :c])
+    assert_equal %({"b":2}), ActiveSupport::JSON.encode({ "foo" => "bar", :b => 2, :c => 3 }, { except: ["foo", :c] })
   end
 
   def test_time_to_json_includes_local_offset
     with_standard_json_time_format(true) do
-      with_env_tz 'US/Eastern' do
-        assert_equal %("2005-02-01T15:15:10.000-05:00"), ActiveSupport::JSON.encode(Time.local(2005,2,1,15,15,10))
+      with_env_tz "US/Eastern" do
+        assert_equal %("2005-02-01T15:15:10.000-05:00"), ActiveSupport::JSON.encode(Time.local(2005, 2, 1, 15, 15, 10))
       end
     end
   end
 
   def test_hash_with_time_to_json
     with_standard_json_time_format(false) do
-      assert_equal '{"time":"2009/01/01 00:00:00 +0000"}', { :time => Time.utc(2009) }.to_json
+      assert_equal '{"time":"2009/01/01 00:00:00 +0000"}', { time: Time.utc(2009) }.to_json
     end
   end
 
@@ -117,8 +125,8 @@ class TestJSONEncoding < ActiveSupport::TestCase
     assert_nothing_raised do
       hash = {
         "CHI" => {
-          :display_name => "chicago",
-          :latitude => 123.234
+          display_name: "chicago",
+          latitude: 123.234
         }
       }
       ActiveSupport::JSON.encode(hash)
@@ -127,64 +135,64 @@ class TestJSONEncoding < ActiveSupport::TestCase
 
   def test_hash_like_with_options
     h = JSONTest::Hashlike.new
-    json = h.to_json :only => [:foo]
+    json = h.to_json only: [:foo]
 
-    assert_equal({"foo"=>"hello"}, JSON.parse(json))
+    assert_equal({ "foo" => "hello" }, JSON.parse(json))
   end
 
   def test_object_to_json_with_options
     obj = Object.new
     obj.instance_variable_set :@foo, "hello"
     obj.instance_variable_set :@bar, "world"
-    json = obj.to_json :only => ["foo"]
+    json = obj.to_json only: ["foo"]
 
-    assert_equal({"foo"=>"hello"}, JSON.parse(json))
+    assert_equal({ "foo" => "hello" }, JSON.parse(json))
   end
 
   def test_struct_to_json_with_options
     struct = Struct.new(:foo, :bar).new
     struct.foo = "hello"
     struct.bar = "world"
-    json = struct.to_json :only => [:foo]
+    json = struct.to_json only: [:foo]
 
-    assert_equal({"foo"=>"hello"}, JSON.parse(json))
+    assert_equal({ "foo" => "hello" }, JSON.parse(json))
   end
 
   def test_hash_should_pass_encoding_options_to_children_in_as_json
     person = {
-      :name => 'John',
-      :address => {
-        :city => 'London',
-        :country => 'UK'
+      name: "John",
+      address: {
+        city: "London",
+        country: "UK"
       }
     }
-    json = person.as_json :only => [:address, :city]
+    json = person.as_json only: [:address, :city]
 
-    assert_equal({ 'address' => { 'city' => 'London' }}, json)
+    assert_equal({ "address" => { "city" => "London" } }, json)
   end
 
   def test_hash_should_pass_encoding_options_to_children_in_to_json
     person = {
-      :name => 'John',
-      :address => {
-        :city => 'London',
-        :country => 'UK'
+      name: "John",
+      address: {
+        city: "London",
+        country: "UK"
       }
     }
-    json = person.to_json :only => [:address, :city]
+    json = person.to_json only: [:address, :city]
 
     assert_equal(%({"address":{"city":"London"}}), json)
   end
 
   def test_array_should_pass_encoding_options_to_children_in_as_json
     people = [
-      { :name => 'John', :address => { :city => 'London', :country => 'UK' }},
-      { :name => 'Jean', :address => { :city => 'Paris' , :country => 'France' }}
+      { name: "John", address: { city: "London", country: "UK" } },
+      { name: "Jean", address: { city: "Paris", country: "France" } }
     ]
-    json = people.as_json :only => [:address, :city]
+    json = people.as_json only: [:address, :city]
     expected = [
-      { 'address' => { 'city' => 'London' }},
-      { 'address' => { 'city' => 'Paris' }}
+      { "address" => { "city" => "London" } },
+      { "address" => { "city" => "Paris" } }
     ]
 
     assert_equal(expected, json)
@@ -192,20 +200,20 @@ class TestJSONEncoding < ActiveSupport::TestCase
 
   def test_array_should_pass_encoding_options_to_children_in_to_json
     people = [
-      { :name => 'John', :address => { :city => 'London', :country => 'UK' }},
-      { :name => 'Jean', :address => { :city => 'Paris' , :country => 'France' }}
+      { name: "John", address: { city: "London", country: "UK" } },
+      { name: "Jean", address: { city: "Paris", country: "France" } }
     ]
-    json = people.to_json :only => [:address, :city]
+    json = people.to_json only: [:address, :city]
 
     assert_equal(%([{"address":{"city":"London"}},{"address":{"city":"Paris"}}]), json)
   end
 
   People = Class.new(BasicObject) do
     include Enumerable
-    def initialize()
+    def initialize
       @people = [
-        { :name => 'John', :address => { :city => 'London', :country => 'UK' }},
-        { :name => 'Jean', :address => { :city => 'Paris' , :country => 'France' }}
+        { name: "John", address: { city: "London", country: "UK" } },
+        { name: "Jean", address: { city: "Paris", country: "France" } }
       ]
     end
     def each(*, &blk)
@@ -217,32 +225,32 @@ class TestJSONEncoding < ActiveSupport::TestCase
   end
 
   def test_enumerable_should_generate_json_with_as_json
-    json = People.new.as_json :only => [:address, :city]
+    json = People.new.as_json only: [:address, :city]
     expected = [
-      { 'address' => { 'city' => 'London' }},
-      { 'address' => { 'city' => 'Paris' }}
+      { "address" => { "city" => "London" } },
+      { "address" => { "city" => "Paris" } }
     ]
 
     assert_equal(expected, json)
   end
 
   def test_enumerable_should_generate_json_with_to_json
-    json = People.new.to_json :only => [:address, :city]
+    json = People.new.to_json only: [:address, :city]
     assert_equal(%([{"address":{"city":"London"}},{"address":{"city":"Paris"}}]), json)
   end
 
   def test_enumerable_should_pass_encoding_options_to_children_in_as_json
-    json = People.new.each.as_json :only => [:address, :city]
+    json = People.new.each.as_json only: [:address, :city]
     expected = [
-      { 'address' => { 'city' => 'London' }},
-      { 'address' => { 'city' => 'Paris' }}
+      { "address" => { "city" => "London" } },
+      { "address" => { "city" => "Paris" } }
     ]
 
     assert_equal(expected, json)
   end
 
   def test_enumerable_should_pass_encoding_options_to_children_in_to_json
-    json = People.new.each.to_json :only => [:address, :city]
+    json = People.new.each.to_json only: [:address, :city]
 
     assert_equal(%([{"address":{"city":"London"}},{"address":{"city":"Paris"}}]), json)
   end
@@ -250,7 +258,7 @@ class TestJSONEncoding < ActiveSupport::TestCase
   class CustomWithOptions
     attr_accessor :foo, :bar
 
-    def as_json(options={})
+    def as_json(options = {})
       options[:only] = %w(foo bar)
       super(options)
     end
@@ -261,9 +269,9 @@ class TestJSONEncoding < ActiveSupport::TestCase
     f.foo = "hello"
     f.bar = "world"
 
-    hash = {"foo" => f, "other_hash" => {"foo" => "other_foo", "test" => "other_test"}}
-    assert_equal({"foo"=>{"foo"=>"hello","bar"=>"world"},
-                  "other_hash" => {"foo"=>"other_foo","test"=>"other_test"}}, ActiveSupport::JSON.decode(hash.to_json))
+    hash = { "foo" => f, "other_hash" => { "foo" => "other_foo", "test" => "other_test" } }
+    assert_equal({ "foo" => { "foo" => "hello", "bar" => "world" },
+                  "other_hash" => { "foo" => "other_foo", "test" => "other_test" } }, ActiveSupport::JSON.decode(hash.to_json))
   end
 
   def test_array_to_json_should_not_keep_options_around
@@ -271,9 +279,9 @@ class TestJSONEncoding < ActiveSupport::TestCase
     f.foo = "hello"
     f.bar = "world"
 
-    array = [f, {"foo" => "other_foo", "test" => "other_test"}]
-    assert_equal([{"foo"=>"hello","bar"=>"world"},
-                  {"foo"=>"other_foo","test"=>"other_test"}], ActiveSupport::JSON.decode(array.to_json))
+    array = [f, { "foo" => "other_foo", "test" => "other_test" }]
+    assert_equal([{ "foo" => "hello", "bar" => "world" },
+                  { "foo" => "other_foo", "test" => "other_test" }], ActiveSupport::JSON.decode(array.to_json))
   end
 
   class OptionsTest
@@ -284,7 +292,7 @@ class TestJSONEncoding < ActiveSupport::TestCase
 
   def test_hash_as_json_without_options
     json = { foo: OptionsTest.new }.as_json
-    assert_equal({"foo" => :default}, json)
+    assert_equal({ "foo" => :default }, json)
   end
 
   def test_array_as_json_without_options
@@ -293,13 +301,12 @@ class TestJSONEncoding < ActiveSupport::TestCase
   end
 
   def test_struct_encoding
-    Struct.new('UserNameAndEmail', :name, :email)
-    Struct.new('UserNameAndDate', :name, :date)
-    Struct.new('Custom', :name, :sub)
-    user_email = Struct::UserNameAndEmail.new 'David', 'sample@example.com'
-    user_birthday = Struct::UserNameAndDate.new 'David', Date.new(2010, 01, 01)
-    custom = Struct::Custom.new 'David', user_birthday
-
+    Struct.new("UserNameAndEmail", :name, :email)
+    Struct.new("UserNameAndDate", :name, :date)
+    Struct.new("Custom", :name, :sub)
+    user_email = Struct::UserNameAndEmail.new "David", "sample@example.com"
+    user_birthday = Struct::UserNameAndDate.new "David", Date.new(2010, 01, 01)
+    custom = Struct::Custom.new "David", user_birthday
 
     json_strings = ""
     json_string_and_date = ""
@@ -311,20 +318,20 @@ class TestJSONEncoding < ActiveSupport::TestCase
       json_custom = custom.to_json
     end
 
-    assert_equal({"name" => "David",
+    assert_equal({ "name" => "David",
                   "sub" => {
                     "name" => "David",
-                    "date" => "2010-01-01" }}, ActiveSupport::JSON.decode(json_custom))
+                    "date" => "2010-01-01" } }, ActiveSupport::JSON.decode(json_custom))
 
-    assert_equal({"name" => "David", "email" => "sample@example.com"},
+    assert_equal({ "name" => "David", "email" => "sample@example.com" },
                  ActiveSupport::JSON.decode(json_strings))
 
-    assert_equal({"name" => "David", "date" => "2010-01-01"},
+    assert_equal({ "name" => "David", "date" => "2010-01-01" },
                  ActiveSupport::JSON.decode(json_string_and_date))
   end
 
   def test_nil_true_and_false_represented_as_themselves
-    assert_equal nil,   nil.as_json
+    assert_nil nil.as_json
     assert_equal true,  true.as_json
     assert_equal false, false.as_json
   end
@@ -336,7 +343,7 @@ class TestJSONEncoding < ActiveSupport::TestCase
       super
     end
 
-    def as_json(options={})
+    def as_json(options = {})
       @as_json_called = true
       super
     end
@@ -376,7 +383,7 @@ EXPECTED
 
   def test_twz_to_json_with_use_standard_json_time_format_config_set_to_false
     with_standard_json_time_format(false) do
-      zone = ActiveSupport::TimeZone['Eastern Time (US & Canada)']
+      zone = ActiveSupport::TimeZone["Eastern Time (US & Canada)"]
       time = ActiveSupport::TimeWithZone.new(Time.utc(2000), zone)
       assert_equal "\"1999/12/31 19:00:00 -0500\"", ActiveSupport::JSON.encode(time)
     end
@@ -384,7 +391,7 @@ EXPECTED
 
   def test_twz_to_json_with_use_standard_json_time_format_config_set_to_true
     with_standard_json_time_format(true) do
-      zone = ActiveSupport::TimeZone['Eastern Time (US & Canada)']
+      zone = ActiveSupport::TimeZone["Eastern Time (US & Canada)"]
       time = ActiveSupport::TimeWithZone.new(Time.utc(2000), zone)
       assert_equal "\"1999-12-31T19:00:00.000-05:00\"", ActiveSupport::JSON.encode(time)
     end
@@ -393,7 +400,7 @@ EXPECTED
   def test_twz_to_json_with_custom_time_precision
     with_standard_json_time_format(true) do
       with_time_precision(0) do
-        zone = ActiveSupport::TimeZone['Eastern Time (US & Canada)']
+        zone = ActiveSupport::TimeZone["Eastern Time (US & Canada)"]
         time = ActiveSupport::TimeWithZone.new(Time.utc(2000), zone)
         assert_equal "\"1999-12-31T19:00:00-05:00\"", ActiveSupport::JSON.encode(time)
       end
@@ -417,7 +424,7 @@ EXPECTED
   end
 
   def test_twz_to_json_when_wrapping_a_date_time
-    zone = ActiveSupport::TimeZone['Eastern Time (US & Canada)']
+    zone = ActiveSupport::TimeZone["Eastern Time (US & Canada)"]
     time = ActiveSupport::TimeWithZone.new(DateTime.new(2000), zone)
     assert_equal '"1999-12-31T19:00:00.000-05:00"', ActiveSupport::JSON.encode(time)
   end
@@ -427,7 +434,31 @@ EXPECTED
     assert_equal '"foo"', ActiveSupport::JSON.encode(exception)
   end
 
-  protected
+  class InfiniteNumber
+    def as_json(options = nil)
+      { "number" => Float::INFINITY }
+    end
+  end
+
+  def test_to_json_works_when_as_json_returns_infinite_number
+    assert_equal '{"number":null}', InfiniteNumber.new.to_json
+  end
+
+  class NaNNumber
+    def as_json(options = nil)
+      { "number" => Float::NAN }
+    end
+  end
+
+  def test_to_json_works_when_as_json_returns_NaN_number
+    assert_equal '{"number":null}', NaNNumber.new.to_json
+  end
+
+  def test_to_json_works_on_io_objects
+    assert_equal STDOUT.to_s.to_json, STDOUT.to_json
+  end
+
+  private
 
     def object_keys(json_object)
       json_object[1..-2].scan(/([^{}:,\s]+):/).flatten.sort
diff --git a/activesupport/test/json/encoding_test_cases.rb b/activesupport/test/json/encoding_test_cases.rb
index 0159ba8606..5a4700459f 100644
--- a/activesupport/test/json/encoding_test_cases.rb
+++ b/activesupport/test/json/encoding_test_cases.rb
@@ -1,4 +1,10 @@
-require 'bigdecimal'
+# frozen_string_literal: true
+
+require "bigdecimal"
+require "date"
+require "time"
+require "pathname"
+require "uri"
 
 module JSONTest
   class Foo
@@ -9,7 +15,7 @@ module JSONTest
 
   class Hashlike
     def to_hash
-      { :foo => "hello", :bar => "world" }
+      { foo: "hello", bar: "world" }
     end
   end
 
@@ -23,7 +29,7 @@ module JSONTest
     end
   end
 
-  class MyStruct < Struct.new(:name, :value)
+  MyStruct = Struct.new(:name, :value) do
     def initialize(*)
       @unused = "unused instance variable"
       super
@@ -36,23 +42,23 @@ module JSONTest
     NilTests      = [[ nil,   %(null)  ]]
     NumericTests  = [[ 1,     %(1)     ],
                      [ 2.5,   %(2.5)   ],
-                     [ 0.0/0.0,   %(null) ],
-                     [ 1.0/0.0,   %(null) ],
-                     [ -1.0/0.0,  %(null) ],
-                     [ BigDecimal('0.0')/BigDecimal('0.0'),  %(null) ],
-                     [ BigDecimal('2.5'), %("#{BigDecimal('2.5')}") ]]
+                     [ 0.0 / 0.0,   %(null) ],
+                     [ 1.0 / 0.0,   %(null) ],
+                     [ -1.0 / 0.0,  %(null) ],
+                     [ BigDecimal("0.0") / BigDecimal("0.0"),  %(null) ],
+                     [ BigDecimal("2.5"), %("#{BigDecimal('2.5')}") ]]
 
-    StringTests   = [[ 'this is the <string>',     %("this is the \\u003cstring\\u003e")],
+    StringTests   = [[ "this is the <string>",     %("this is the \\u003cstring\\u003e")],
                      [ 'a "string" with quotes & an ampersand', %("a \\"string\\" with quotes \\u0026 an ampersand") ],
-                     [ 'http://test.host/posts/1', %("http://test.host/posts/1")],
+                     [ "http://test.host/posts/1", %("http://test.host/posts/1")],
                      [ "Control characters: \x00\x01\x02\x03\x04\x05\x06\x07\x08\x09\x0a\x0b\x0c\x0d\x0e\x0f\x10\x11\x12\x13\x14\x15\x16\x17\x18\x19\x1a\x1b\x1c\x1d\x1e\x1f\u2028\u2029",
                        %("Control characters: \\u0000\\u0001\\u0002\\u0003\\u0004\\u0005\\u0006\\u0007\\b\\t\\n\\u000b\\f\\r\\u000e\\u000f\\u0010\\u0011\\u0012\\u0013\\u0014\\u0015\\u0016\\u0017\\u0018\\u0019\\u001a\\u001b\\u001c\\u001d\\u001e\\u001f\\u2028\\u2029") ]]
 
-    ArrayTests    = [[ ['a', 'b', 'c'],          %([\"a\",\"b\",\"c\"])        ],
-                     [ [1, 'a', :b, nil, false], %([1,\"a\",\"b\",null,false]) ]]
+    ArrayTests    = [[ ["a", "b", "c"],          %([\"a\",\"b\",\"c\"])        ],
+                     [ [1, "a", :b, nil, false], %([1,\"a\",\"b\",null,false]) ]]
 
-    HashTests     = [[ {foo: "bar"}, %({\"foo\":\"bar\"}) ],
-                     [ {1 => 1, 2 => 'a', 3 => :b, 4 => nil, 5 => false}, %({\"1\":1,\"2\":\"a\",\"3\":\"b\",\"4\":null,\"5\":false}) ]]
+    HashTests     = [[ { foo: "bar" }, %({\"foo\":\"bar\"}) ],
+                     [ { 1 => 1, 2 => "a", 3 => :b, 4 => nil, 5 => false }, %({\"1\":1,\"2\":\"a\",\"3\":\"b\",\"4\":null,\"5\":false}) ]]
 
     RangeTests    = [[ 1..2,     %("1..2")],
                      [ 1...2,    %("1...2")],
@@ -67,22 +73,26 @@ module JSONTest
     StructTests   = [[ MyStruct.new(:foo, "bar"), %({\"name\":\"foo\",\"value\":\"bar\"}) ],
                      [ MyStruct.new(nil, nil), %({\"name\":null,\"value\":null}) ]]
     CustomTests   = [[ Custom.new("custom"), '"custom"' ],
-                     [ Custom.new(nil), 'null' ],
+                     [ Custom.new(nil), "null" ],
                      [ Custom.new(:a), '"a"' ],
                      [ Custom.new([ :foo, "bar" ]), '["foo","bar"]' ],
-                     [ Custom.new({ :foo => "hello", :bar => "world" }), '{"bar":"world","foo":"hello"}' ],
+                     [ Custom.new(foo: "hello", bar: "world"), '{"bar":"world","foo":"hello"}' ],
                      [ Custom.new(Hashlike.new), '{"bar":"world","foo":"hello"}' ],
                      [ Custom.new(Custom.new(Custom.new(:a))), '"a"' ]]
 
     RegexpTests   = [[ /^a/, '"(?-mix:^a)"' ], [/^\w{1,2}[a-z]+/ix, '"(?ix-m:^\\\\w{1,2}[a-z]+)"']]
 
-    DateTests     = [[ Date.new(2005,2,1), %("2005/02/01") ]]
-    TimeTests     = [[ Time.utc(2005,2,1,15,15,10), %("2005/02/01 15:15:10 +0000") ]]
-    DateTimeTests = [[ DateTime.civil(2005,2,1,15,15,10), %("2005/02/01 15:15:10 +0000") ]]
+    URITests      = [[ URI.parse("http://example.com"), %("http://example.com") ]]
+
+    PathnameTests = [[ Pathname.new("lib/index.rb"), %("lib/index.rb") ]]
+
+    DateTests     = [[ Date.new(2005, 2, 1), %("2005/02/01") ]]
+    TimeTests     = [[ Time.utc(2005, 2, 1, 15, 15, 10), %("2005/02/01 15:15:10 +0000") ]]
+    DateTimeTests = [[ DateTime.civil(2005, 2, 1, 15, 15, 10), %("2005/02/01 15:15:10 +0000") ]]
 
-    StandardDateTests     = [[ Date.new(2005,2,1), %("2005-02-01") ]]
-    StandardTimeTests     = [[ Time.utc(2005,2,1,15,15,10), %("2005-02-01T15:15:10.000Z") ]]
-    StandardDateTimeTests = [[ DateTime.civil(2005,2,1,15,15,10), %("2005-02-01T15:15:10.000+00:00") ]]
-    StandardStringTests   = [[ 'this is the <string>', %("this is the <string>")]]
+    StandardDateTests     = [[ Date.new(2005, 2, 1), %("2005-02-01") ]]
+    StandardTimeTests     = [[ Time.utc(2005, 2, 1, 15, 15, 10), %("2005-02-01T15:15:10.000Z") ]]
+    StandardDateTimeTests = [[ DateTime.civil(2005, 2, 1, 15, 15, 10), %("2005-02-01T15:15:10.000+00:00") ]]
+    StandardStringTests   = [[ "this is the <string>", %("this is the <string>")]]
   end
 end
diff --git a/activesupport/test/key_generator_test.rb b/activesupport/test/key_generator_test.rb
index f7e8e9a795..a948cfbd8e 100644
--- a/activesupport/test/key_generator_test.rb
+++ b/activesupport/test/key_generator_test.rb
@@ -1,62 +1,79 @@
-require 'abstract_unit'
+# frozen_string_literal: true
+
+require "abstract_unit"
 
 begin
-  require 'openssl'
+  require "openssl"
   OpenSSL::PKCS5
 rescue LoadError, NameError
   $stderr.puts "Skipping KeyGenerator test: broken OpenSSL install"
 else
 
-require 'active_support/time'
-require 'active_support/json'
+  require "active_support/time"
+  require "active_support/json"
 
-class KeyGeneratorTest < ActiveSupport::TestCase
-  def setup
-    @secret    = SecureRandom.hex(64)
-    @generator = ActiveSupport::KeyGenerator.new(@secret, :iterations=>2)
-  end
+  class KeyGeneratorTest < ActiveSupport::TestCase
+    def setup
+      @secret    = SecureRandom.hex(64)
+      @generator = ActiveSupport::KeyGenerator.new(@secret, iterations: 2)
+    end
 
-  test "Generating a key of the default length" do
-    derived_key = @generator.generate_key("some_salt")
-    assert_kind_of String, derived_key
-    assert_equal OpenSSL::Digest::SHA1.new.block_length, derived_key.length, "Should have generated a key of the default size"
-  end
+    test "Generating a key of the default length" do
+      derived_key = @generator.generate_key("some_salt")
+      assert_kind_of String, derived_key
+      assert_equal 64, derived_key.length, "Should have generated a key of the default size"
+    end
 
-  test "Generating a key of an alternative length" do
-    derived_key = @generator.generate_key("some_salt", 32)
-    assert_kind_of String, derived_key
-    assert_equal 32, derived_key.length, "Should have generated a key of the right size"
-  end
-end
+    test "Generating a key of an alternative length" do
+      derived_key = @generator.generate_key("some_salt", 32)
+      assert_kind_of String, derived_key
+      assert_equal 32, derived_key.length, "Should have generated a key of the right size"
+    end
 
-class CachingKeyGeneratorTest < ActiveSupport::TestCase
-  def setup
-    @secret    = SecureRandom.hex(64)
-    @generator = ActiveSupport::KeyGenerator.new(@secret, :iterations=>2)
-    @caching_generator = ActiveSupport::CachingKeyGenerator.new(@generator)
-  end
+    test "Expected results" do
+      # For any given set of inputs, this method must continue to return
+      # the same output: if it changes, any existing values relying on a
+      # key would break.
 
-  test "Generating a cached key for same salt and key size" do
-    derived_key = @caching_generator.generate_key("some_salt", 32)
-    cached_key = @caching_generator.generate_key("some_salt", 32)
+      expected = "b129376f68f1ecae788d7433310249d65ceec090ecacd4c872a3a9e9ec78e055739be5cc6956345d5ae38e7e1daa66f1de587dc8da2bf9e8b965af4b3918a122"
+      assert_equal expected, ActiveSupport::KeyGenerator.new("0" * 64).generate_key("some_salt").unpack("H*").first
 
-    assert_equal derived_key, cached_key
-    assert_equal derived_key.object_id, cached_key.object_id
+      expected = "b129376f68f1ecae788d7433310249d65ceec090ecacd4c872a3a9e9ec78e055"
+      assert_equal expected, ActiveSupport::KeyGenerator.new("0" * 64).generate_key("some_salt", 32).unpack("H*").first
+
+      expected = "cbea7f7f47df705967dc508f4e446fd99e7797b1d70011c6899cd39bbe62907b8508337d678505a7dc8184e037f1003ba3d19fc5d829454668e91d2518692eae"
+      assert_equal expected, ActiveSupport::KeyGenerator.new("0" * 64, iterations: 2).generate_key("some_salt").unpack("H*").first
+    end
   end
 
-  test "Does not cache key for different salt" do
-    derived_key = @caching_generator.generate_key("some_salt", 32)
-    different_salt_key = @caching_generator.generate_key("other_salt", 32)
+  class CachingKeyGeneratorTest < ActiveSupport::TestCase
+    def setup
+      @secret    = SecureRandom.hex(64)
+      @generator = ActiveSupport::KeyGenerator.new(@secret, iterations: 2)
+      @caching_generator = ActiveSupport::CachingKeyGenerator.new(@generator)
+    end
 
-    assert_not_equal derived_key, different_salt_key
-  end
+    test "Generating a cached key for same salt and key size" do
+      derived_key = @caching_generator.generate_key("some_salt", 32)
+      cached_key = @caching_generator.generate_key("some_salt", 32)
+
+      assert_equal derived_key, cached_key
+      assert_equal derived_key.object_id, cached_key.object_id
+    end
 
-  test "Does not cache key for different length" do
-    derived_key = @caching_generator.generate_key("some_salt", 32)
-    different_length_key = @caching_generator.generate_key("some_salt", 64)
+    test "Does not cache key for different salt" do
+      derived_key = @caching_generator.generate_key("some_salt", 32)
+      different_salt_key = @caching_generator.generate_key("other_salt", 32)
 
-    assert_not_equal derived_key, different_length_key
+      assert_not_equal derived_key, different_salt_key
+    end
+
+    test "Does not cache key for different length" do
+      derived_key = @caching_generator.generate_key("some_salt", 32)
+      different_length_key = @caching_generator.generate_key("some_salt", 64)
+
+      assert_not_equal derived_key, different_length_key
+    end
   end
-end
 
 end
diff --git a/activesupport/test/lazy_load_hooks_test.rb b/activesupport/test/lazy_load_hooks_test.rb
index 7851634dbf..721d44d0c1 100644
--- a/activesupport/test/lazy_load_hooks_test.rb
+++ b/activesupport/test/lazy_load_hooks_test.rb
@@ -1,4 +1,6 @@
-require 'abstract_unit'
+# frozen_string_literal: true
+
+require "abstract_unit"
 
 class LazyLoadHooksTest < ActiveSupport::TestCase
   def test_basic_hook
@@ -18,6 +20,23 @@ class LazyLoadHooksTest < ActiveSupport::TestCase
     assert_equal 7, i
   end
 
+  def test_basic_hook_with_two_registrations_only_once
+    i = 0
+    block = proc { i += incr }
+    ActiveSupport.on_load(:basic_hook_with_two_once, run_once: true, &block)
+    ActiveSupport.on_load(:basic_hook_with_two_once) do
+      i += incr
+    end
+
+    ActiveSupport.on_load(:different_hook, run_once: true, &block)
+    ActiveSupport.run_load_hooks(:different_hook, FakeContext.new(2))
+    assert_equal 2, i
+    ActiveSupport.run_load_hooks(:basic_hook_with_two_once, FakeContext.new(2))
+    assert_equal 6, i
+    ActiveSupport.run_load_hooks(:basic_hook_with_two_once, FakeContext.new(5))
+    assert_equal 11, i
+  end
+
   def test_hook_registered_after_run
     i = 0
     ActiveSupport.run_load_hooks(:registered_after)
@@ -35,6 +54,15 @@ class LazyLoadHooksTest < ActiveSupport::TestCase
     assert_equal 7, i
   end
 
+  def test_hook_registered_after_run_with_two_registrations_only_once
+    i = 0
+    ActiveSupport.run_load_hooks(:registered_after_with_two_once, FakeContext.new(2))
+    ActiveSupport.run_load_hooks(:registered_after_with_two_once, FakeContext.new(5))
+    assert_equal 0, i
+    ActiveSupport.on_load(:registered_after_with_two_once, run_once: true) { i += incr }
+    assert_equal 2, i
+  end
+
   def test_hook_registered_interleaved_run_with_two_registrations
     i = 0
     ActiveSupport.run_load_hooks(:registered_interleaved_with_two, FakeContext.new(2))
@@ -45,6 +73,22 @@ class LazyLoadHooksTest < ActiveSupport::TestCase
     assert_equal 7, i
   end
 
+  def test_hook_registered_interleaved_run_with_two_registrations_once
+    i = 0
+    ActiveSupport
+      .run_load_hooks(:registered_interleaved_with_two_once, FakeContext.new(2))
+    assert_equal 0, i
+
+    ActiveSupport.on_load(:registered_interleaved_with_two_once, run_once: true) do
+      i += incr
+    end
+    assert_equal 2, i
+
+    ActiveSupport
+      .run_load_hooks(:registered_interleaved_with_two_once, FakeContext.new(5))
+    assert_equal 2, i
+  end
+
   def test_hook_receives_a_context
     i = 0
     ActiveSupport.on_load(:contextual) { i += incr }
@@ -63,7 +107,7 @@ class LazyLoadHooksTest < ActiveSupport::TestCase
 
   def test_hook_with_yield_true
     i = 0
-    ActiveSupport.on_load(:contextual_yield, :yield => true) do |obj|
+    ActiveSupport.on_load(:contextual_yield, yield: true) do |obj|
       i += obj.incr + incr_amt
     end
     assert_equal 0, i
@@ -75,7 +119,7 @@ class LazyLoadHooksTest < ActiveSupport::TestCase
     i = 0
     ActiveSupport.run_load_hooks(:contextual_yield_after, FakeContext.new(2))
     assert_equal 0, i
-    ActiveSupport.on_load(:contextual_yield_after, :yield => true) do |obj|
+    ActiveSupport.on_load(:contextual_yield_after, yield: true) do |obj|
       i += obj.incr + incr_amt
     end
     assert_equal 7, i
@@ -93,4 +137,4 @@ private
       @incr = incr
     end
   end
-end
\ No newline at end of file
+end
diff --git a/activesupport/test/load_paths_test.rb b/activesupport/test/load_paths_test.rb
deleted file mode 100644
index ac617a9fd8..0000000000
--- a/activesupport/test/load_paths_test.rb
+++ /dev/null
@@ -1,16 +0,0 @@
-require 'abstract_unit'
-
-class LoadPathsTest < ActiveSupport::TestCase
-  def test_uniq_load_paths
-    load_paths_count = $LOAD_PATH.inject({}) { |paths, path|
-      expanded_path = File.expand_path(path)
-      paths[expanded_path] ||= 0
-      paths[expanded_path] += 1
-      paths
-    }
-    load_paths_count[File.expand_path('../../lib', __FILE__)] -= 1
-
-    load_paths_count.select! { |k, v| v > 1 }
-    assert load_paths_count.empty?, load_paths_count.inspect
-  end
-end
diff --git a/activesupport/test/log_subscriber_test.rb b/activesupport/test/log_subscriber_test.rb
index 998a6887c5..2af9b1de30 100644
--- a/activesupport/test/log_subscriber_test.rb
+++ b/activesupport/test/log_subscriber_test.rb
@@ -1,5 +1,7 @@
-require 'abstract_unit'
-require 'active_support/log_subscriber/test_helper'
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "active_support/log_subscriber/test_helper"
 
 class MyLogSubscriber < ActiveSupport::LogSubscriber
   attr_reader :event
@@ -116,7 +118,7 @@ class SyncLogSubscriberTest < ActiveSupport::TestCase
     wait
 
     assert_equal 1, @logger.logged(:info).size
-    assert_equal 'some_event.my_log_subscriber', @logger.logged(:info).last
+    assert_equal "some_event.my_log_subscriber", @logger.logged(:info).last
 
     assert_equal 1, @logger.logged(:error).size
     assert_match 'Could not log "puke.my_log_subscriber" event. RuntimeError: puke', @logger.logged(:error).last
diff --git a/activesupport/test/logger_test.rb b/activesupport/test/logger_test.rb
index dfc5f3fdf4..5efbd10a7d 100644
--- a/activesupport/test/logger_test.rb
+++ b/activesupport/test/logger_test.rb
@@ -1,9 +1,11 @@
-require 'abstract_unit'
-require 'multibyte_test_helpers'
-require 'stringio'
-require 'fileutils'
-require 'tempfile'
-require 'concurrent/atomics'
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "multibyte_test_helpers"
+require "stringio"
+require "fileutils"
+require "tempfile"
+require "concurrent/atomics"
 
 class LoggerTest < ActiveSupport::TestCase
   include MultibyteTestHelpers
@@ -26,18 +28,18 @@ class LoggerTest < ActiveSupport::TestCase
   end
 
   def test_write_binary_data_to_existing_file
-    t = Tempfile.new ['development', 'log']
+    t = Tempfile.new ["development", "log"]
     t.binmode
-    t.write 'hi mom!'
+    t.write "hi mom!"
     t.close
 
-    f = File.open(t.path, 'w')
+    f = File.open(t.path, "w")
     f.binmode
 
     logger = Logger.new f
     logger.level = Logger::DEBUG
 
-    str = "\x80"
+    str = "\x80".dup
     str.force_encoding("ASCII-8BIT")
 
     logger.add Logger::DEBUG, str
@@ -47,15 +49,15 @@ class LoggerTest < ActiveSupport::TestCase
   end
 
   def test_write_binary_data_create_file
-    fname = File.join Dir.tmpdir, 'lol', 'rofl.log'
+    fname = File.join Dir.tmpdir, "lol", "rofl.log"
     FileUtils.mkdir_p File.dirname(fname)
-    f = File.open(fname, 'w')
+    f = File.open(fname, "w")
     f.binmode
 
     logger = Logger.new f
     logger.level = Logger::DEBUG
 
-    str = "\x80"
+    str = "\x80".dup
     str.force_encoding("ASCII-8BIT")
 
     logger.add Logger::DEBUG, str
@@ -67,7 +69,7 @@ class LoggerTest < ActiveSupport::TestCase
   def test_should_log_debugging_message_when_debugging
     @logger.level = Logger::DEBUG
     @logger.add(Logger::DEBUG, @message)
-    assert @output.string.include?(@message)
+    assert_includes @output.string, @message
   end
 
   def test_should_not_log_debug_messages_when_log_level_is_info
@@ -78,32 +80,32 @@ class LoggerTest < ActiveSupport::TestCase
 
   def test_should_add_message_passed_as_block_when_using_add
     @logger.level = Logger::INFO
-    @logger.add(Logger::INFO) {@message}
-    assert @output.string.include?(@message)
+    @logger.add(Logger::INFO) { @message }
+    assert_includes @output.string, @message
   end
 
   def test_should_add_message_passed_as_block_when_using_shortcut
     @logger.level = Logger::INFO
-    @logger.info {@message}
-    assert @output.string.include?(@message)
+    @logger.info { @message }
+    assert_includes @output.string, @message
   end
 
   def test_should_convert_message_to_string
     @logger.level = Logger::INFO
     @logger.info @integer_message
-    assert @output.string.include?(@integer_message.to_s)
+    assert_includes @output.string, @integer_message.to_s
   end
 
   def test_should_convert_message_to_string_when_passed_in_block
     @logger.level = Logger::INFO
-    @logger.info {@integer_message}
-    assert @output.string.include?(@integer_message.to_s)
+    @logger.info { @integer_message }
+    assert_includes @output.string, @integer_message.to_s
   end
 
   def test_should_not_evaluate_block_if_message_wont_be_logged
     @logger.level = Logger::INFO
     evaluated = false
-    @logger.add(Logger::DEBUG) {evaluated = true}
+    @logger.add(Logger::DEBUG) { evaluated = true }
     assert evaluated == false
   end
 
@@ -115,7 +117,7 @@ class LoggerTest < ActiveSupport::TestCase
 
   def test_should_know_if_its_loglevel_is_below_a_given_level
     Logger::Severity.constants.each do |level|
-      next if level.to_s == 'UNKNOWN'
+      next if level.to_s == "UNKNOWN"
       @logger.level = Logger::Severity.const_get(level) - 1
       assert @logger.send("#{level.downcase}?"), "didn't know if it was #{level.downcase}? or below"
     end
@@ -125,10 +127,10 @@ class LoggerTest < ActiveSupport::TestCase
     @logger.level = Logger::INFO
     @logger.info(UNICODE_STRING)
     @logger.info(BYTE_STRING)
-    assert @output.string.include?(UNICODE_STRING)
+    assert_includes @output.string, UNICODE_STRING
     byte_string = @output.string.dup
     byte_string.force_encoding("ASCII-8BIT")
-    assert byte_string.include?(BYTE_STRING)
+    assert_includes byte_string, BYTE_STRING
   end
 
   def test_silencing_everything_but_errors
@@ -138,7 +140,7 @@ class LoggerTest < ActiveSupport::TestCase
     end
 
     assert_not @output.string.include?("NOT THERE")
-    assert @output.string.include?("THIS IS HERE")
+    assert_includes @output.string, "THIS IS HERE"
   end
 
   def test_logger_silencing_works_for_broadcast
@@ -154,12 +156,12 @@ class LoggerTest < ActiveSupport::TestCase
       @logger.error "CORRECT ERROR"
     end
 
-    assert @output.string.include?("CORRECT DEBUG")
-    assert @output.string.include?("CORRECT ERROR")
+    assert_includes @output.string, "CORRECT DEBUG"
+    assert_includes @output.string, "CORRECT ERROR"
     assert_not @output.string.include?("FAILURE")
 
-    assert another_output.string.include?("CORRECT DEBUG")
-    assert another_output.string.include?("CORRECT ERROR")
+    assert_includes another_output.string, "CORRECT DEBUG"
+    assert_includes another_output.string, "CORRECT ERROR"
     assert_not another_output.string.include?("FAILURE")
   end
 
@@ -176,13 +178,13 @@ class LoggerTest < ActiveSupport::TestCase
       @logger.error "CORRECT ERROR"
     end
 
-    assert @output.string.include?("CORRECT DEBUG")
-    assert @output.string.include?("CORRECT ERROR")
+    assert_includes @output.string, "CORRECT DEBUG"
+    assert_includes @output.string, "CORRECT ERROR"
     assert_not @output.string.include?("FAILURE")
 
-    assert another_output.string.include?("CORRECT DEBUG")
-    assert another_output.string.include?("CORRECT ERROR")
-    assert another_output.string.include?("FAILURE")
+    assert_includes another_output.string, "CORRECT DEBUG"
+    assert_includes another_output.string, "CORRECT ERROR"
+    assert_includes another_output.string, "FAILURE"
     # We can't silence plain ruby Logger cause with thread safety
     # but at least we don't break it
   end
diff --git a/activesupport/test/message_encryptor_test.rb b/activesupport/test/message_encryptor_test.rb
index eb71369397..9edf07f762 100644
--- a/activesupport/test/message_encryptor_test.rb
+++ b/activesupport/test/message_encryptor_test.rb
@@ -1,7 +1,10 @@
-require 'abstract_unit'
-require 'openssl'
-require 'active_support/time'
-require 'active_support/json'
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "openssl"
+require "active_support/time"
+require "active_support/json"
+require_relative "metadata/shared_metadata_tests"
 
 class MessageEncryptorTest < ActiveSupport::TestCase
   class JSONSerializer
@@ -15,10 +18,10 @@ class MessageEncryptorTest < ActiveSupport::TestCase
   end
 
   def setup
-    @secret    = SecureRandom.hex(64)
-    @verifier  = ActiveSupport::MessageVerifier.new(@secret, :serializer => ActiveSupport::MessageEncryptor::NullSerializer)
+    @secret    = SecureRandom.random_bytes(32)
+    @verifier  = ActiveSupport::MessageVerifier.new(@secret, serializer: ActiveSupport::MessageEncryptor::NullSerializer)
     @encryptor = ActiveSupport::MessageEncryptor.new(@secret)
-    @data = { :some => "data", :now => Time.local(2010) }
+    @data = { some: "data", now: Time.local(2010) }
   end
 
   def test_encrypting_twice_yields_differing_cipher_text
@@ -48,11 +51,21 @@ class MessageEncryptorTest < ActiveSupport::TestCase
     assert_equal @data, @encryptor.decrypt_and_verify(message)
   end
 
+  def test_backwards_compat_for_64_bytes_key
+    # 64 bit key
+    secret = ["3942b1bf81e622559ed509e3ff274a780784fe9e75b065866bd270438c74da822219de3156473cc27df1fd590e4baf68c95eeb537b6e4d4c5a10f41635b5597e"].pack("H*")
+    # Encryptor with 32 bit key, 64 bit secret for verifier
+    encryptor = ActiveSupport::MessageEncryptor.new(secret[0..31], secret)
+    # Message generated with 64 bit key
+    message = "eHdGeExnZEwvMSt3U3dKaFl1WFo0TjVvYzA0eGpjbm5WSkt5MXlsNzhpZ0ZnbWhBWFlQZTRwaXE1bVJCS2oxMDZhYVp2dVN3V0lNZUlWQ3c2eVhQbnhnVjFmeVVubmhRKzF3WnZyWHVNMDg9LS1HSisyakJVSFlPb05ISzRMaXRzcFdBPT0=--831a1d54a3cda8a0658dc668a03dedcbce13b5ca"
+    assert_equal "data", encryptor.decrypt_and_verify(message)[:some]
+  end
+
   def test_alternative_serialization_method
     prev = ActiveSupport.use_standard_json_time_format
     ActiveSupport.use_standard_json_time_format = true
-    encryptor = ActiveSupport::MessageEncryptor.new(SecureRandom.hex(64), SecureRandom.hex(64), :serializer => JSONSerializer.new)
-    message = encryptor.encrypt_and_sign({ :foo => 123, 'bar' => Time.utc(2010) })
+    encryptor = ActiveSupport::MessageEncryptor.new(SecureRandom.random_bytes(32), SecureRandom.random_bytes(128), serializer: JSONSerializer.new)
+    message = encryptor.encrypt_and_sign(:foo => 123, "bar" => Time.utc(2010))
     exp = { "foo" => 123, "bar" => "2010-01-01T00:00:00.000Z" }
     assert_equal exp, encryptor.decrypt_and_verify(message)
   ensure
@@ -61,7 +74,7 @@ class MessageEncryptorTest < ActiveSupport::TestCase
 
   def test_message_obeys_strict_encoding
     bad_encoding_characters = "\n!@#"
-    message, iv = @encryptor.encrypt_and_sign("This is a very \n\nhumble string"+bad_encoding_characters)
+    message, iv = @encryptor.encrypt_and_sign("This is a very \n\nhumble string" + bad_encoding_characters)
 
     assert_not_decrypted("#{::Base64.encode64 message.to_s}--#{::Base64.encode64 iv.to_s}")
     assert_not_verified("#{::Base64.encode64 message.to_s}--#{::Base64.encode64 iv.to_s}")
@@ -70,23 +83,164 @@ class MessageEncryptorTest < ActiveSupport::TestCase
     assert_not_verified([iv,  message] * bad_encoding_characters)
   end
 
+  def test_aead_mode_encryption
+    encryptor = ActiveSupport::MessageEncryptor.new(@secret, cipher: "aes-256-gcm")
+    message = encryptor.encrypt_and_sign(@data)
+    assert_equal @data, encryptor.decrypt_and_verify(message)
+  end
+
+  def test_aead_mode_with_hmac_cbc_cipher_text
+    encryptor = ActiveSupport::MessageEncryptor.new(@secret, cipher: "aes-256-gcm")
+
+    assert_aead_not_decrypted(encryptor, "eHdGeExnZEwvMSt3U3dKaFl1WFo0TjVvYzA0eGpjbm5WSkt5MXlsNzhpZ0ZnbWhBWFlQZTRwaXE1bVJCS2oxMDZhYVp2dVN3V0lNZUlWQ3c2eVhQbnhnVjFmeVVubmhRKzF3WnZyWHVNMDg9LS1HSisyakJVSFlPb05ISzRMaXRzcFdBPT0=--831a1d54a3cda8a0658dc668a03dedcbce13b5ca")
+  end
+
+  def test_messing_with_aead_values_causes_failures
+    encryptor = ActiveSupport::MessageEncryptor.new(@secret, cipher: "aes-256-gcm")
+    text, iv, auth_tag = encryptor.encrypt_and_sign(@data).split("--")
+    assert_aead_not_decrypted(encryptor, [iv, text, auth_tag] * "--")
+    assert_aead_not_decrypted(encryptor, [munge(text), iv, auth_tag] * "--")
+    assert_aead_not_decrypted(encryptor, [text, munge(iv), auth_tag] * "--")
+    assert_aead_not_decrypted(encryptor, [text, iv, munge(auth_tag)] * "--")
+    assert_aead_not_decrypted(encryptor, [munge(text), munge(iv), munge(auth_tag)] * "--")
+    assert_aead_not_decrypted(encryptor, [text, iv] * "--")
+    assert_aead_not_decrypted(encryptor, [text, iv, auth_tag[0..-2]] * "--")
+  end
+
+  def test_backwards_compatibility_decrypt_previously_encrypted_messages_without_metadata
+    secret = "\xB7\xF0\xBCW\xB1\x18`\xAB\xF0\x81\x10\xA4$\xF44\xEC\xA1\xDC\xC1\xDDD\xAF\xA9\xB8\x14\xCD\x18\x9A\x99 \x80)"
+    encryptor = ActiveSupport::MessageEncryptor.new(secret, cipher: "aes-256-gcm")
+    encrypted_message = "9cVnFs2O3lL9SPvIJuxBOLS51nDiBMw=--YNI5HAfHEmZ7VDpl--ddFJ6tXA0iH+XGcCgMINYQ=="
+
+    assert_equal "Ruby on Rails", encryptor.decrypt_and_verify(encrypted_message)
+  end
+
+  def test_rotating_secret
+    old_message = ActiveSupport::MessageEncryptor.new(secrets[:old], cipher: "aes-256-gcm").encrypt_and_sign("old")
+
+    encryptor = ActiveSupport::MessageEncryptor.new(@secret, cipher: "aes-256-gcm")
+    encryptor.rotate secrets[:old]
+
+    assert_equal "old", encryptor.decrypt_and_verify(old_message)
+  end
+
+  def test_rotating_serializer
+    old_message = ActiveSupport::MessageEncryptor.new(secrets[:old], cipher: "aes-256-gcm", serializer: JSON).
+      encrypt_and_sign(ahoy: :hoy)
+
+    encryptor = ActiveSupport::MessageEncryptor.new(@secret, cipher: "aes-256-gcm", serializer: JSON)
+    encryptor.rotate secrets[:old]
+
+    assert_equal({ "ahoy" => "hoy" }, encryptor.decrypt_and_verify(old_message))
+  end
+
+  def test_rotating_aes_cbc_secrets
+    old_encryptor = ActiveSupport::MessageEncryptor.new(secrets[:old], "old sign", cipher: "aes-256-cbc")
+    old_message = old_encryptor.encrypt_and_sign("old")
+
+    encryptor = ActiveSupport::MessageEncryptor.new(@secret)
+    encryptor.rotate secrets[:old], "old sign", cipher: "aes-256-cbc"
+
+    assert_equal "old", encryptor.decrypt_and_verify(old_message)
+  end
+
+  def test_multiple_rotations
+    older_message = ActiveSupport::MessageEncryptor.new(secrets[:older], "older sign").encrypt_and_sign("older")
+    old_message = ActiveSupport::MessageEncryptor.new(secrets[:old], "old sign").encrypt_and_sign("old")
+
+    encryptor = ActiveSupport::MessageEncryptor.new(@secret)
+    encryptor.rotate secrets[:old], "old sign"
+    encryptor.rotate secrets[:older], "older sign"
+
+    assert_equal "new",   encryptor.decrypt_and_verify(encryptor.encrypt_and_sign("new"))
+    assert_equal "old",   encryptor.decrypt_and_verify(old_message)
+    assert_equal "older", encryptor.decrypt_and_verify(older_message)
+  end
+
+  def test_on_rotation_is_called_and_returns_modified_messages
+    older_message = ActiveSupport::MessageEncryptor.new(secrets[:older], "older sign").encrypt_and_sign(encoded: "message")
+
+    encryptor = ActiveSupport::MessageEncryptor.new(@secret)
+    encryptor.rotate secrets[:old]
+    encryptor.rotate secrets[:older], "older sign"
+
+    rotated = false
+    message = encryptor.decrypt_and_verify(older_message, on_rotation: proc { rotated = true })
+
+    assert_equal({ encoded: "message" }, message)
+    assert rotated
+  end
+
+  def test_with_rotated_metadata
+    old_message = ActiveSupport::MessageEncryptor.new(secrets[:old], cipher: "aes-256-gcm").
+      encrypt_and_sign("metadata", purpose: :rotation)
+
+    encryptor = ActiveSupport::MessageEncryptor.new(@secret, cipher: "aes-256-gcm")
+    encryptor.rotate secrets[:old]
+
+    assert_equal "metadata", encryptor.decrypt_and_verify(old_message, purpose: :rotation)
+  end
+
   private
+    def assert_aead_not_decrypted(encryptor, value)
+      assert_raise(ActiveSupport::MessageEncryptor::InvalidMessage) do
+        encryptor.decrypt_and_verify(value)
+      end
+    end
 
-  def assert_not_decrypted(value)
-    assert_raise(ActiveSupport::MessageEncryptor::InvalidMessage) do
-      @encryptor.decrypt_and_verify(@verifier.generate(value))
+    def assert_not_decrypted(value)
+      assert_raise(ActiveSupport::MessageEncryptor::InvalidMessage) do
+        @encryptor.decrypt_and_verify(@verifier.generate(value))
+      end
     end
-  end
 
-  def assert_not_verified(value)
-    assert_raise(ActiveSupport::MessageVerifier::InvalidSignature) do
-      @encryptor.decrypt_and_verify(value)
+    def assert_not_verified(value)
+      assert_raise(ActiveSupport::MessageVerifier::InvalidSignature) do
+        @encryptor.decrypt_and_verify(value)
+      end
     end
-  end
 
-  def munge(base64_string)
-    bits = ::Base64.strict_decode64(base64_string)
-    bits.reverse!
-    ::Base64.strict_encode64(bits)
+    def secrets
+      @secrets ||= Hash.new { |h, k| h[k] = SecureRandom.random_bytes(32) }
+    end
+
+    def munge(base64_string)
+      bits = ::Base64.strict_decode64(base64_string)
+      bits.reverse!
+      ::Base64.strict_encode64(bits)
+    end
+end
+
+class MessageEncryptorMetadataTest < ActiveSupport::TestCase
+  include SharedMessageMetadataTests
+
+  setup do
+    @secret    = SecureRandom.random_bytes(32)
+    @encryptor = ActiveSupport::MessageEncryptor.new(@secret, encryptor_options)
   end
+
+  private
+    def generate(message, **options)
+      @encryptor.encrypt_and_sign(message, options)
+    end
+
+    def parse(data, **options)
+      @encryptor.decrypt_and_verify(data, options)
+    end
+
+    def encryptor_options; end
+end
+
+class MessageEncryptorMetadataMarshalTest < MessageEncryptorMetadataTest
+  private
+    def encryptor_options
+      { serializer: Marshal }
+    end
+end
+
+class MessageEncryptorMetadataJSONTest < MessageEncryptorMetadataTest
+  private
+    def encryptor_options
+      { serializer: MessageEncryptorTest::JSONSerializer.new }
+    end
 end
diff --git a/activesupport/test/message_verifier_test.rb b/activesupport/test/message_verifier_test.rb
index 668d78492e..05d5c1cbc3 100644
--- a/activesupport/test/message_verifier_test.rb
+++ b/activesupport/test/message_verifier_test.rb
@@ -1,10 +1,12 @@
-require 'abstract_unit'
-require 'openssl'
-require 'active_support/time'
-require 'active_support/json'
+# frozen_string_literal: true
 
-class MessageVerifierTest < ActiveSupport::TestCase
+require "abstract_unit"
+require "openssl"
+require "active_support/time"
+require "active_support/json"
+require_relative "metadata/shared_metadata_tests"
 
+class MessageVerifierTest < ActiveSupport::TestCase
   class JSONSerializer
     def dump(value)
       ActiveSupport::JSON.encode(value)
@@ -17,7 +19,8 @@ class MessageVerifierTest < ActiveSupport::TestCase
 
   def setup
     @verifier = ActiveSupport::MessageVerifier.new("Hey, I'm a secret!")
-    @data = { :some => "data", :now => Time.local(2010) }
+    @data = { some: "data", now: Time.utc(2010) }
+    @secret = SecureRandom.random_bytes(32)
   end
 
   def test_valid_message
@@ -49,8 +52,8 @@ class MessageVerifierTest < ActiveSupport::TestCase
   def test_alternative_serialization_method
     prev = ActiveSupport.use_standard_json_time_format
     ActiveSupport.use_standard_json_time_format = true
-    verifier = ActiveSupport::MessageVerifier.new("Hey, I'm a secret!", :serializer => JSONSerializer.new)
-    message = verifier.generate({ :foo => 123, 'bar' => Time.utc(2010) })
+    verifier = ActiveSupport::MessageVerifier.new("Hey, I'm a secret!", serializer: JSONSerializer.new)
+    message = verifier.generate(:foo => 123, "bar" => Time.utc(2010))
     exp = { "foo" => 123, "bar" => "2010-01-01T00:00:00.000Z" }
     assert_equal exp, verifier.verified(message)
     assert_equal exp, verifier.verify(message)
@@ -81,6 +84,121 @@ class MessageVerifierTest < ActiveSupport::TestCase
     exception = assert_raise(ArgumentError) do
       ActiveSupport::MessageVerifier.new(nil)
     end
-    assert_equal exception.message, 'Secret should not be nil.'
+    assert_equal "Secret should not be nil.", exception.message
+  end
+
+  def test_backward_compatibility_messages_signed_without_metadata
+    signed_message = "BAh7BzoJc29tZUkiCWRhdGEGOgZFVDoIbm93SXU6CVRpbWUNIIAbgAAAAAAHOgtvZmZzZXRpADoJem9uZUkiCFVUQwY7BkY=--d03c52c91dfe4ccc5159417c660461bcce005e96"
+    assert_equal @data, @verifier.verify(signed_message)
+  end
+
+  def test_rotating_secret
+    old_message = ActiveSupport::MessageVerifier.new("old", digest: "SHA1").generate("old")
+
+    verifier = ActiveSupport::MessageVerifier.new(@secret, digest: "SHA1")
+    verifier.rotate "old"
+
+    assert_equal "old", verifier.verified(old_message)
   end
+
+  def test_multiple_rotations
+    old_message   = ActiveSupport::MessageVerifier.new("old", digest: "SHA256").generate("old")
+    older_message = ActiveSupport::MessageVerifier.new("older", digest: "SHA1").generate("older")
+
+    verifier = ActiveSupport::MessageVerifier.new(@secret, digest: "SHA512")
+    verifier.rotate "old",   digest: "SHA256"
+    verifier.rotate "older", digest: "SHA1"
+
+    assert_equal "new",   verifier.verified(verifier.generate("new"))
+    assert_equal "old",   verifier.verified(old_message)
+    assert_equal "older", verifier.verified(older_message)
+  end
+
+  def test_on_rotation_is_called_and_verified_returns_message
+    older_message = ActiveSupport::MessageVerifier.new("older", digest: "SHA1").generate(encoded: "message")
+
+    verifier = ActiveSupport::MessageVerifier.new(@secret, digest: "SHA512")
+    verifier.rotate "old",   digest: "SHA256"
+    verifier.rotate "older", digest: "SHA1"
+
+    rotated = false
+    message = verifier.verified(older_message, on_rotation: proc { rotated = true })
+
+    assert_equal({ encoded: "message" }, message)
+    assert rotated
+  end
+
+  def test_rotations_with_metadata
+    old_message = ActiveSupport::MessageVerifier.new("old").generate("old", purpose: :rotation)
+
+    verifier = ActiveSupport::MessageVerifier.new(@secret)
+    verifier.rotate "old"
+
+    assert_equal "old", verifier.verified(old_message, purpose: :rotation)
+  end
+end
+
+class MessageVerifierMetadataTest < ActiveSupport::TestCase
+  include SharedMessageMetadataTests
+
+  setup do
+    @verifier = ActiveSupport::MessageVerifier.new("Hey, I'm a secret!", verifier_options)
+  end
+
+  def test_verify_raises_when_purpose_differs
+    assert_raise(ActiveSupport::MessageVerifier::InvalidSignature) do
+      @verifier.verify(generate(data, purpose: "payment"), purpose: "shipping")
+    end
+  end
+
+  def test_verify_raises_when_expired
+    signed_message = generate(data, expires_in: 1.month)
+
+    travel 2.months
+    assert_raise(ActiveSupport::MessageVerifier::InvalidSignature) do
+      @verifier.verify(signed_message)
+    end
+  end
+
+  private
+    def generate(message, **options)
+      @verifier.generate(message, options)
+    end
+
+    def parse(message, **options)
+      @verifier.verified(message, options)
+    end
+
+    def verifier_options
+      Hash.new
+    end
+end
+
+class MessageVerifierMetadataMarshalTest < MessageVerifierMetadataTest
+  private
+    def verifier_options
+      { serializer: Marshal }
+    end
+end
+
+class MessageVerifierMetadataJSONTest < MessageVerifierMetadataTest
+  private
+    def verifier_options
+      { serializer: MessageVerifierTest::JSONSerializer.new }
+    end
+end
+
+class MessageEncryptorMetadataNullSerializerTest < MessageVerifierMetadataTest
+  private
+    def data
+      "string message"
+    end
+
+    def null_serializing?
+      true
+    end
+
+    def verifier_options
+      { serializer: ActiveSupport::MessageEncryptor::NullSerializer }
+    end
 end
diff --git a/activesupport/test/messages/rotation_configuration_test.rb b/activesupport/test/messages/rotation_configuration_test.rb
new file mode 100644
index 0000000000..2f6824ed21
--- /dev/null
+++ b/activesupport/test/messages/rotation_configuration_test.rb
@@ -0,0 +1,25 @@
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "active_support/messages/rotation_configuration"
+
+class MessagesRotationConfiguration < ActiveSupport::TestCase
+  def setup
+    @config = ActiveSupport::Messages::RotationConfiguration.new
+  end
+
+  def test_signed_configurations
+    @config.rotate :signed, "older secret", salt: "salt", digest: "SHA1"
+    @config.rotate :signed, "old secret", salt: "salt", digest: "SHA256"
+
+    assert_equal [
+      [ "older secret", salt: "salt", digest: "SHA1" ],
+      [ "old secret", salt: "salt", digest: "SHA256" ] ], @config.signed
+  end
+
+  def test_encrypted_configurations
+    @config.rotate :encrypted, "old raw key", cipher: "aes-256-gcm"
+
+    assert_equal [ [ "old raw key", cipher: "aes-256-gcm" ] ], @config.encrypted
+  end
+end
diff --git a/activesupport/test/metadata/shared_metadata_tests.rb b/activesupport/test/metadata/shared_metadata_tests.rb
new file mode 100644
index 0000000000..08bb0c648e
--- /dev/null
+++ b/activesupport/test/metadata/shared_metadata_tests.rb
@@ -0,0 +1,93 @@
+# frozen_string_literal: true
+
+module SharedMessageMetadataTests
+  def teardown
+    travel_back
+    super
+  end
+
+  def null_serializing?
+    false
+  end
+
+  def test_encryption_and_decryption_with_same_purpose
+    assert_equal data, parse(generate(data, purpose: "checkout"), purpose: "checkout")
+    assert_equal data, parse(generate(data))
+
+    string_message = "address: #23, main street"
+    assert_equal string_message, parse(generate(string_message, purpose: "shipping"), purpose: "shipping")
+  end
+
+  def test_verifies_array_when_purpose_matches
+    unless null_serializing?
+      data = [ "credit_card_no: 5012-6748-9087-5678", { "card_holder" => "Donald", "issued_on" => Time.local(2017) }, 12345 ]
+      assert_equal data, parse(generate(data, purpose: :registration), purpose: :registration)
+    end
+  end
+
+  def test_encryption_and_decryption_with_different_purposes_returns_nil
+    assert_nil parse(generate(data, purpose: "payment"), purpose: "sign up")
+    assert_nil parse(generate(data, purpose: "payment"))
+    assert_nil parse(generate(data), purpose: "sign up")
+  end
+
+  def test_purpose_using_symbols
+    assert_equal data, parse(generate(data, purpose: :checkout), purpose: :checkout)
+    assert_equal data, parse(generate(data, purpose: :checkout), purpose: "checkout")
+    assert_equal data, parse(generate(data, purpose: "checkout"), purpose: :checkout)
+  end
+
+  def test_passing_expires_at_sets_expiration_date
+    encrypted_message = generate(data, expires_at: 1.hour.from_now)
+
+    travel 59.minutes
+    assert_equal data, parse(encrypted_message)
+
+    travel 2.minutes
+    assert_nil parse(encrypted_message)
+  end
+
+  def test_set_relative_expiration_date_by_passing_expires_in
+    encrypted_message = generate(data, expires_in: 2.hours)
+
+    travel 1.hour
+    assert_equal data, parse(encrypted_message)
+
+    travel 1.hour + 1.second
+    assert_nil parse(encrypted_message)
+  end
+
+  def test_passing_expires_in_less_than_a_second_is_not_expired
+    freeze_time do
+      encrypted_message = generate(data, expires_in: 1.second)
+
+      travel 0.5.seconds
+      assert_equal data, parse(encrypted_message)
+
+      travel 1.second
+      assert_nil parse(encrypted_message)
+    end
+  end
+
+  def test_favor_expires_at_over_expires_in
+    payment_related_message = generate(data, purpose: "payment", expires_at: 2.year.from_now, expires_in: 1.second)
+
+    travel 1.year
+    assert_equal data, parse(payment_related_message, purpose: :payment)
+
+    travel 1.year + 1.day
+    assert_nil parse(payment_related_message, purpose: "payment")
+  end
+
+  def test_skip_expires_at_and_expires_in_to_disable_expiration_check
+    payment_related_message = generate(data, purpose: "payment")
+
+    travel 100.years
+    assert_equal data, parse(payment_related_message, purpose: "payment")
+  end
+
+  private
+    def data
+      { "credit_card_no" => "5012-6784-9087-5678", "card_holder" => { "name" => "Donald" } }
+    end
+end
diff --git a/activesupport/test/multibyte_chars_test.rb b/activesupport/test/multibyte_chars_test.rb
index c1e0b19248..f51fbe2671 100644
--- a/activesupport/test/multibyte_chars_test.rb
+++ b/activesupport/test/multibyte_chars_test.rb
@@ -1,6 +1,8 @@
-require 'abstract_unit'
-require 'multibyte_test_helpers'
-require 'active_support/core_ext/string/multibyte'
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "multibyte_test_helpers"
+require "active_support/core_ext/string/multibyte"
 
 class MultibyteCharsTest < ActiveSupport::TestCase
   include MultibyteTestHelpers
@@ -16,7 +18,7 @@ class MultibyteCharsTest < ActiveSupport::TestCase
   end
 
   def test_should_allow_method_calls_to_string
-    @chars.wrapped_string.singleton_class.class_eval { def __method_for_multibyte_testing; 'result'; end }
+    @chars.wrapped_string.singleton_class.class_eval { def __method_for_multibyte_testing; "result"; end }
 
     assert_nothing_raised do
       @chars.__method_for_multibyte_testing
@@ -27,14 +29,14 @@ class MultibyteCharsTest < ActiveSupport::TestCase
   end
 
   def test_forwarded_method_calls_should_return_new_chars_instance
-    @chars.wrapped_string.singleton_class.class_eval { def __method_for_multibyte_testing; 'result'; end }
+    @chars.wrapped_string.singleton_class.class_eval { def __method_for_multibyte_testing; "result"; end }
 
     assert_kind_of @proxy_class, @chars.__method_for_multibyte_testing
     assert_not_equal @chars.object_id, @chars.__method_for_multibyte_testing.object_id
   end
 
   def test_forwarded_bang_method_calls_should_return_the_original_chars_instance_when_result_is_not_nil
-    @chars.wrapped_string.singleton_class.class_eval { def __method_for_multibyte_testing!; 'result'; end }
+    @chars.wrapped_string.singleton_class.class_eval { def __method_for_multibyte_testing!; "result"; end }
 
     assert_kind_of @proxy_class, @chars.__method_for_multibyte_testing!
     assert_equal @chars.object_id, @chars.__method_for_multibyte_testing!.object_id
@@ -50,8 +52,8 @@ class MultibyteCharsTest < ActiveSupport::TestCase
     assert_equal BYTE_STRING.length, BYTE_STRING.mb_chars.length
   end
 
-  def test_forwarded_method_with_non_string_result_should_be_returned_vertabim
-    str = ''
+  def test_forwarded_method_with_non_string_result_should_be_returned_verbatim
+    str = "".dup
     str.singleton_class.class_eval { def __method_for_multibyte_testing_with_integer_result; 1; end }
     @chars.wrapped_string.singleton_class.class_eval { def __method_for_multibyte_testing_with_integer_result; 1; end }
 
@@ -59,15 +61,15 @@ class MultibyteCharsTest < ActiveSupport::TestCase
   end
 
   def test_should_concatenate
-    mb_a = 'a'.mb_chars
-    mb_b = 'b'.mb_chars
-    assert_equal 'ab', mb_a + 'b'
-    assert_equal 'ab', 'a' + mb_b
-    assert_equal 'ab', mb_a + mb_b
+    mb_a = "a".dup.mb_chars
+    mb_b = "b".dup.mb_chars
+    assert_equal "ab", mb_a + "b"
+    assert_equal "ab", "a" + mb_b
+    assert_equal "ab", mb_a + mb_b
 
-    assert_equal 'ab', mb_a << 'b'
-    assert_equal 'ab', 'a' << mb_b
-    assert_equal 'abb', mb_a << mb_b
+    assert_equal "ab", mb_a << "b"
+    assert_equal "ab", "a".dup << mb_b
+    assert_equal "abb", mb_a << mb_b
   end
 
   def test_consumes_utf8_strings
@@ -77,8 +79,8 @@ class MultibyteCharsTest < ActiveSupport::TestCase
   end
 
   def test_concatenation_should_return_a_proxy_class_instance
-    assert_equal ActiveSupport::Multibyte.proxy_class, ('a'.mb_chars + 'b').class
-    assert_equal ActiveSupport::Multibyte.proxy_class, ('a'.mb_chars << 'b').class
+    assert_equal ActiveSupport::Multibyte.proxy_class, ("a".mb_chars + "b").class
+    assert_equal ActiveSupport::Multibyte.proxy_class, ("a".dup.mb_chars << "b").class
   end
 
   def test_ascii_strings_are_treated_at_utf8_strings
@@ -86,10 +88,10 @@ class MultibyteCharsTest < ActiveSupport::TestCase
   end
 
   def test_concatenate_should_return_proxy_instance
-    assert(('a'.mb_chars + 'b').kind_of?(@proxy_class))
-    assert(('a'.mb_chars + 'b'.mb_chars).kind_of?(@proxy_class))
-    assert(('a'.mb_chars << 'b').kind_of?(@proxy_class))
-    assert(('a'.mb_chars << 'b'.mb_chars).kind_of?(@proxy_class))
+    assert(("a".mb_chars + "b").kind_of?(@proxy_class))
+    assert(("a".mb_chars + "b".mb_chars).kind_of?(@proxy_class))
+    assert(("a".dup.mb_chars << "b").kind_of?(@proxy_class))
+    assert(("a".dup.mb_chars << "b".mb_chars).kind_of?(@proxy_class))
   end
 
   def test_should_return_string_as_json
@@ -115,12 +117,12 @@ class MultibyteCharsUTF8BehaviourTest < ActiveSupport::TestCase
   %w{capitalize downcase lstrip reverse rstrip swapcase upcase}.each do |method|
     class_eval(<<-EOTESTS, __FILE__, __LINE__ + 1)
       def test_#{method}_bang_should_return_self_when_modifying_wrapped_string
-        chars = ' él piDió Un bUen café '
+        chars = ' él piDió Un bUen café '.dup
         assert_equal chars.object_id, chars.send("#{method}!").object_id
       end
 
       def test_#{method}_bang_should_change_wrapped_string
-        original = ' él piDió Un bUen café '
+        original = ' él piDió Un bUen café '.dup
         proxy = chars(original.dup)
         proxy.send("#{method}!")
         assert_not_equal original, proxy.to_s
@@ -133,7 +135,7 @@ class MultibyteCharsUTF8BehaviourTest < ActiveSupport::TestCase
   end
 
   def test_tidy_bytes_bang_should_change_wrapped_string
-    original = " Un bUen café \x92"
+    original = " Un bUen café \x92".dup
     proxy = chars(original.dup)
     proxy.tidy_bytes!
     assert_not_equal original, proxy.to_s
@@ -150,24 +152,24 @@ class MultibyteCharsUTF8BehaviourTest < ActiveSupport::TestCase
   end
 
   def test_string_methods_are_chainable
-    assert chars('').insert(0, '').kind_of?(ActiveSupport::Multibyte.proxy_class)
-    assert chars('').rjust(1).kind_of?(ActiveSupport::Multibyte.proxy_class)
-    assert chars('').ljust(1).kind_of?(ActiveSupport::Multibyte.proxy_class)
-    assert chars('').center(1).kind_of?(ActiveSupport::Multibyte.proxy_class)
-    assert chars('').rstrip.kind_of?(ActiveSupport::Multibyte.proxy_class)
-    assert chars('').lstrip.kind_of?(ActiveSupport::Multibyte.proxy_class)
-    assert chars('').strip.kind_of?(ActiveSupport::Multibyte.proxy_class)
-    assert chars('').reverse.kind_of?(ActiveSupport::Multibyte.proxy_class)
-    assert chars(' ').slice(0).kind_of?(ActiveSupport::Multibyte.proxy_class)
-    assert chars('').limit(0).kind_of?(ActiveSupport::Multibyte.proxy_class)
-    assert chars('').upcase.kind_of?(ActiveSupport::Multibyte.proxy_class)
-    assert chars('').downcase.kind_of?(ActiveSupport::Multibyte.proxy_class)
-    assert chars('').capitalize.kind_of?(ActiveSupport::Multibyte.proxy_class)
-    assert chars('').normalize.kind_of?(ActiveSupport::Multibyte.proxy_class)
-    assert chars('').decompose.kind_of?(ActiveSupport::Multibyte.proxy_class)
-    assert chars('').compose.kind_of?(ActiveSupport::Multibyte.proxy_class)
-    assert chars('').tidy_bytes.kind_of?(ActiveSupport::Multibyte.proxy_class)
-    assert chars('').swapcase.kind_of?(ActiveSupport::Multibyte.proxy_class)
+    assert chars("".dup).insert(0, "").kind_of?(ActiveSupport::Multibyte.proxy_class)
+    assert chars("").rjust(1).kind_of?(ActiveSupport::Multibyte.proxy_class)
+    assert chars("").ljust(1).kind_of?(ActiveSupport::Multibyte.proxy_class)
+    assert chars("").center(1).kind_of?(ActiveSupport::Multibyte.proxy_class)
+    assert chars("").rstrip.kind_of?(ActiveSupport::Multibyte.proxy_class)
+    assert chars("").lstrip.kind_of?(ActiveSupport::Multibyte.proxy_class)
+    assert chars("").strip.kind_of?(ActiveSupport::Multibyte.proxy_class)
+    assert chars("").reverse.kind_of?(ActiveSupport::Multibyte.proxy_class)
+    assert chars(" ").slice(0).kind_of?(ActiveSupport::Multibyte.proxy_class)
+    assert chars("").limit(0).kind_of?(ActiveSupport::Multibyte.proxy_class)
+    assert chars("").upcase.kind_of?(ActiveSupport::Multibyte.proxy_class)
+    assert chars("").downcase.kind_of?(ActiveSupport::Multibyte.proxy_class)
+    assert chars("").capitalize.kind_of?(ActiveSupport::Multibyte.proxy_class)
+    assert chars("").normalize.kind_of?(ActiveSupport::Multibyte.proxy_class)
+    assert chars("").decompose.kind_of?(ActiveSupport::Multibyte.proxy_class)
+    assert chars("").compose.kind_of?(ActiveSupport::Multibyte.proxy_class)
+    assert chars("").tidy_bytes.kind_of?(ActiveSupport::Multibyte.proxy_class)
+    assert chars("").swapcase.kind_of?(ActiveSupport::Multibyte.proxy_class)
   end
 
   def test_should_be_equal_to_the_wrapped_string
@@ -176,8 +178,8 @@ class MultibyteCharsUTF8BehaviourTest < ActiveSupport::TestCase
   end
 
   def test_should_not_be_equal_to_an_other_string
-    assert_not_equal @chars, 'other'
-    assert_not_equal 'other', @chars
+    assert_not_equal @chars, "other"
+    assert_not_equal "other", @chars
   end
 
   def test_sortability
@@ -195,29 +197,29 @@ class MultibyteCharsUTF8BehaviourTest < ActiveSupport::TestCase
   end
 
   def test_should_use_character_offsets_for_insert_offsets
-    assert_equal '', ''.mb_chars.insert(0, '')
-    assert_equal 'こわにちわ', @chars.insert(1, 'わ')
-    assert_equal 'こわわわにちわ', @chars.insert(2, 'わわ')
-    assert_equal 'わこわわわにちわ', @chars.insert(0, 'わ')
-    assert_equal 'わこわわわにちわ', @chars.wrapped_string
+    assert_equal "", "".dup.mb_chars.insert(0, "")
+    assert_equal "こわにちわ", @chars.insert(1, "わ")
+    assert_equal "こわわわにちわ", @chars.insert(2, "わわ")
+    assert_equal "わこわわわにちわ", @chars.insert(0, "わ")
+    assert_equal "わこわわわにちわ", @chars.wrapped_string
   end
 
   def test_insert_should_be_destructive
-    @chars.insert(1, 'わ')
-    assert_equal 'こわにちわ', @chars
+    @chars.insert(1, "わ")
+    assert_equal "こわにちわ", @chars
   end
 
   def test_insert_throws_index_error
-    assert_raise(IndexError) { @chars.insert(-12, 'わ')}
-    assert_raise(IndexError) { @chars.insert(12, 'わ') }
+    assert_raise(IndexError) { @chars.insert(-12, "わ") }
+    assert_raise(IndexError) { @chars.insert(12, "わ") }
   end
 
   def test_should_know_if_one_includes_the_other
-    assert @chars.include?('')
-    assert @chars.include?('ち')
-    assert @chars.include?('わ')
-    assert !@chars.include?('こちわ')
-    assert !@chars.include?('a')
+    assert_includes @chars, ""
+    assert_includes @chars, "ち"
+    assert_includes @chars, "わ"
+    assert_not_includes @chars, "こちわ"
+    assert_not_includes @chars, "a"
   end
 
   def test_include_raises_when_nil_is_passed
@@ -227,62 +229,62 @@ class MultibyteCharsUTF8BehaviourTest < ActiveSupport::TestCase
   end
 
   def test_index_should_return_character_offset
-    assert_nil @chars.index('u')
-    assert_equal 0, @chars.index('こに')
-    assert_equal 2, @chars.index('ち')
-    assert_equal 2, @chars.index('ち', -2)
-    assert_equal nil, @chars.index('ち', -1)
-    assert_equal 3, @chars.index('わ')
-    assert_equal 5, 'ééxééx'.mb_chars.index('x', 4)
+    assert_nil @chars.index("u")
+    assert_equal 0, @chars.index("こに")
+    assert_equal 2, @chars.index("ち")
+    assert_equal 2, @chars.index("ち", -2)
+    assert_nil @chars.index("ち", -1)
+    assert_equal 3, @chars.index("わ")
+    assert_equal 5, "ééxééx".mb_chars.index("x", 4)
   end
 
   def test_rindex_should_return_character_offset
-    assert_nil @chars.rindex('u')
-    assert_equal 1, @chars.rindex('に')
-    assert_equal 2, @chars.rindex('ち', -2)
-    assert_nil @chars.rindex('ち', -3)
-    assert_equal 6, 'Café périferôl'.mb_chars.rindex('é')
-    assert_equal 13, 'Café périferôl'.mb_chars.rindex(/\w/u)
+    assert_nil @chars.rindex("u")
+    assert_equal 1, @chars.rindex("に")
+    assert_equal 2, @chars.rindex("ち", -2)
+    assert_nil @chars.rindex("ち", -3)
+    assert_equal 6, "Café périferôl".mb_chars.rindex("é")
+    assert_equal 13, "Café périferôl".mb_chars.rindex(/\w/u)
   end
 
   def test_indexed_insert_should_take_character_offsets
-    @chars[2] = 'a'
-    assert_equal 'こにaわ', @chars
-    @chars[2] = 'ηη'
-    assert_equal 'こにηηわ', @chars
-    @chars[3, 2] = 'λλλ'
-    assert_equal 'こにηλλλ', @chars
+    @chars[2] = "a"
+    assert_equal "こにaわ", @chars
+    @chars[2] = "ηη"
+    assert_equal "こにηηわ", @chars
+    @chars[3, 2] = "λλλ"
+    assert_equal "こにηλλλ", @chars
     @chars[1, 0] = "λ"
-    assert_equal 'こλにηλλλ', @chars
+    assert_equal "こλにηλλλ", @chars
     @chars[4..6] = "ηη"
-    assert_equal 'こλにηηη', @chars
+    assert_equal "こλにηηη", @chars
     @chars[/ηη/] = "λλλ"
-    assert_equal 'こλにλλλη', @chars
+    assert_equal "こλにλλλη", @chars
     @chars[/(λλ)(.)/, 2] = "α"
-    assert_equal 'こλにλλαη', @chars
+    assert_equal "こλにλλαη", @chars
     @chars["α"] = "¢"
-    assert_equal 'こλにλλ¢η', @chars
+    assert_equal "こλにλλ¢η", @chars
     @chars["λλ"] = "ααα"
-    assert_equal 'こλにααα¢η', @chars
+    assert_equal "こλにααα¢η", @chars
   end
 
   def test_indexed_insert_should_raise_on_index_overflow
     before = @chars.to_s
-    assert_raise(IndexError) { @chars[10] = 'a' }
-    assert_raise(IndexError) { @chars[10, 4] = 'a' }
-    assert_raise(IndexError) { @chars[/ii/] = 'a' }
-    assert_raise(IndexError) { @chars[/()/, 10] = 'a' }
+    assert_raise(IndexError) { @chars[10] = "a" }
+    assert_raise(IndexError) { @chars[10, 4] = "a" }
+    assert_raise(IndexError) { @chars[/ii/] = "a" }
+    assert_raise(IndexError) { @chars[/()/, 10] = "a" }
     assert_equal before, @chars
   end
 
   def test_indexed_insert_should_raise_on_range_overflow
     before = @chars.to_s
-    assert_raise(RangeError) { @chars[10..12] = 'a' }
+    assert_raise(RangeError) { @chars[10..12] = "a" }
     assert_equal before, @chars
   end
 
   def test_rjust_should_raise_argument_errors_on_bad_arguments
-    assert_raise(ArgumentError) { @chars.rjust(10, '') }
+    assert_raise(ArgumentError) { @chars.rjust(10, "") }
     assert_raise(ArgumentError) { @chars.rjust }
   end
 
@@ -292,15 +294,15 @@ class MultibyteCharsUTF8BehaviourTest < ActiveSupport::TestCase
     assert_equal UNICODE_STRING, @chars.rjust(4)
     assert_equal " #{UNICODE_STRING}", @chars.rjust(5)
     assert_equal "   #{UNICODE_STRING}", @chars.rjust(7)
-    assert_equal "---#{UNICODE_STRING}", @chars.rjust(7, '-')
-    assert_equal "ααα#{UNICODE_STRING}", @chars.rjust(7, 'α')
-    assert_equal "aba#{UNICODE_STRING}", @chars.rjust(7, 'ab')
-    assert_equal "αηα#{UNICODE_STRING}", @chars.rjust(7, 'αη')
-    assert_equal "αηαη#{UNICODE_STRING}", @chars.rjust(8, 'αη')
+    assert_equal "---#{UNICODE_STRING}", @chars.rjust(7, "-")
+    assert_equal "ααα#{UNICODE_STRING}", @chars.rjust(7, "α")
+    assert_equal "aba#{UNICODE_STRING}", @chars.rjust(7, "ab")
+    assert_equal "αηα#{UNICODE_STRING}", @chars.rjust(7, "αη")
+    assert_equal "αηαη#{UNICODE_STRING}", @chars.rjust(8, "αη")
   end
 
   def test_ljust_should_raise_argument_errors_on_bad_arguments
-    assert_raise(ArgumentError) { @chars.ljust(10, '') }
+    assert_raise(ArgumentError) { @chars.ljust(10, "") }
     assert_raise(ArgumentError) { @chars.ljust }
   end
 
@@ -310,15 +312,15 @@ class MultibyteCharsUTF8BehaviourTest < ActiveSupport::TestCase
     assert_equal UNICODE_STRING, @chars.ljust(4)
     assert_equal "#{UNICODE_STRING} ", @chars.ljust(5)
     assert_equal "#{UNICODE_STRING}   ", @chars.ljust(7)
-    assert_equal "#{UNICODE_STRING}---", @chars.ljust(7, '-')
-    assert_equal "#{UNICODE_STRING}ααα", @chars.ljust(7, 'α')
-    assert_equal "#{UNICODE_STRING}aba", @chars.ljust(7, 'ab')
-    assert_equal "#{UNICODE_STRING}αηα", @chars.ljust(7, 'αη')
-    assert_equal "#{UNICODE_STRING}αηαη", @chars.ljust(8, 'αη')
+    assert_equal "#{UNICODE_STRING}---", @chars.ljust(7, "-")
+    assert_equal "#{UNICODE_STRING}ααα", @chars.ljust(7, "α")
+    assert_equal "#{UNICODE_STRING}aba", @chars.ljust(7, "ab")
+    assert_equal "#{UNICODE_STRING}αηα", @chars.ljust(7, "αη")
+    assert_equal "#{UNICODE_STRING}αηαη", @chars.ljust(8, "αη")
   end
 
   def test_center_should_raise_argument_errors_on_bad_arguments
-    assert_raise(ArgumentError) { @chars.center(10, '') }
+    assert_raise(ArgumentError) { @chars.center(10, "") }
     assert_raise(ArgumentError) { @chars.center }
   end
 
@@ -329,15 +331,15 @@ class MultibyteCharsUTF8BehaviourTest < ActiveSupport::TestCase
     assert_equal "#{UNICODE_STRING} ", @chars.center(5)
     assert_equal " #{UNICODE_STRING} ", @chars.center(6)
     assert_equal " #{UNICODE_STRING}  ", @chars.center(7)
-    assert_equal "--#{UNICODE_STRING}--", @chars.center(8, '-')
-    assert_equal "--#{UNICODE_STRING}---", @chars.center(9, '-')
-    assert_equal "αα#{UNICODE_STRING}αα", @chars.center(8, 'α')
-    assert_equal "αα#{UNICODE_STRING}ααα", @chars.center(9, 'α')
-    assert_equal "a#{UNICODE_STRING}ab", @chars.center(7, 'ab')
-    assert_equal "ab#{UNICODE_STRING}ab", @chars.center(8, 'ab')
-    assert_equal "abab#{UNICODE_STRING}abab", @chars.center(12, 'ab')
-    assert_equal "α#{UNICODE_STRING}αη", @chars.center(7, 'αη')
-    assert_equal "αη#{UNICODE_STRING}αη", @chars.center(8, 'αη')
+    assert_equal "--#{UNICODE_STRING}--", @chars.center(8, "-")
+    assert_equal "--#{UNICODE_STRING}---", @chars.center(9, "-")
+    assert_equal "αα#{UNICODE_STRING}αα", @chars.center(8, "α")
+    assert_equal "αα#{UNICODE_STRING}ααα", @chars.center(9, "α")
+    assert_equal "a#{UNICODE_STRING}ab", @chars.center(7, "ab")
+    assert_equal "ab#{UNICODE_STRING}ab", @chars.center(8, "ab")
+    assert_equal "abab#{UNICODE_STRING}abab", @chars.center(12, "ab")
+    assert_equal "α#{UNICODE_STRING}αη", @chars.center(7, "αη")
+    assert_equal "αη#{UNICODE_STRING}αη", @chars.center(8, "αη")
   end
 
   def test_lstrip_strips_whitespace_from_the_left_of_the_string
@@ -367,20 +369,20 @@ class MultibyteCharsUTF8BehaviourTest < ActiveSupport::TestCase
   end
 
   def test_size_returns_characters_instead_of_bytes
-    assert_equal 0, ''.mb_chars.size
+    assert_equal 0, "".mb_chars.size
     assert_equal 4, @chars.size
     assert_equal 4, @chars.length
     assert_equal 5, ASCII_STRING.mb_chars.size
   end
 
   def test_reverse_reverses_characters
-    assert_equal '', ''.mb_chars.reverse
-    assert_equal 'わちにこ', @chars.reverse
+    assert_equal "", "".mb_chars.reverse
+    assert_equal "わちにこ", @chars.reverse
   end
 
   def test_reverse_should_work_with_normalized_strings
-    str = 'bös'
-    reversed_str = 'söb'
+    str = "bös"
+    reversed_str = "söb"
     assert_equal chars(reversed_str).normalize(:kc), chars(str).normalize(:kc).reverse
     assert_equal chars(reversed_str).normalize(:c), chars(str).normalize(:c).reverse
     assert_equal chars(reversed_str).normalize(:d), chars(str).normalize(:d).reverse
@@ -390,45 +392,45 @@ class MultibyteCharsUTF8BehaviourTest < ActiveSupport::TestCase
   end
 
   def test_slice_should_take_character_offsets
-    assert_equal nil, ''.mb_chars.slice(0)
-    assert_equal 'こ', @chars.slice(0)
-    assert_equal 'わ', @chars.slice(3)
-    assert_equal nil, ''.mb_chars.slice(-1..1)
-    assert_equal nil, ''.mb_chars.slice(-1, 1)
-    assert_equal '', ''.mb_chars.slice(0..10)
-    assert_equal 'にちわ', @chars.slice(1..3)
-    assert_equal 'にちわ', @chars.slice(1, 3)
-    assert_equal 'こ', @chars.slice(0, 1)
-    assert_equal 'ちわ', @chars.slice(2..10)
-    assert_equal '', @chars.slice(4..10)
-    assert_equal 'に', @chars.slice(/に/u)
-    assert_equal 'にち', @chars.slice(/に./u)
-    assert_equal nil, @chars.slice(/unknown/u)
-    assert_equal 'にち', @chars.slice(/(にち)/u, 1)
-    assert_equal nil, @chars.slice(/(にち)/u, 2)
-    assert_equal nil, @chars.slice(7..6)
+    assert_nil "".mb_chars.slice(0)
+    assert_equal "こ", @chars.slice(0)
+    assert_equal "わ", @chars.slice(3)
+    assert_nil "".mb_chars.slice(-1..1)
+    assert_nil "".mb_chars.slice(-1, 1)
+    assert_equal "", "".mb_chars.slice(0..10)
+    assert_equal "にちわ", @chars.slice(1..3)
+    assert_equal "にちわ", @chars.slice(1, 3)
+    assert_equal "こ", @chars.slice(0, 1)
+    assert_equal "ちわ", @chars.slice(2..10)
+    assert_equal "", @chars.slice(4..10)
+    assert_equal "に", @chars.slice(/に/u)
+    assert_equal "にち", @chars.slice(/に./u)
+    assert_nil @chars.slice(/unknown/u)
+    assert_equal "にち", @chars.slice(/(にち)/u, 1)
+    assert_nil @chars.slice(/(にち)/u, 2)
+    assert_nil @chars.slice(7..6)
   end
 
   def test_slice_bang_returns_sliced_out_substring
-    assert_equal 'にち', @chars.slice!(1..2)
+    assert_equal "にち", @chars.slice!(1..2)
   end
 
   def test_slice_bang_returns_nil_on_out_of_bound_arguments
-    assert_equal nil, @chars.mb_chars.slice!(9..10)
+    assert_nil @chars.mb_chars.slice!(9..10)
   end
 
   def test_slice_bang_removes_the_slice_from_the_receiver
-    chars = 'úüù'.mb_chars
-    chars.slice!(0,2)
-    assert_equal 'ù', chars
+    chars = "úüù".dup.mb_chars
+    chars.slice!(0, 2)
+    assert_equal "ù", chars
   end
 
   def test_slice_bang_returns_nil_and_does_not_modify_receiver_if_out_of_bounds
-    string = 'úüù'
+    string = "úüù".dup
     chars = string.mb_chars
     assert_nil chars.slice!(4, 5)
-    assert_equal 'úüù', chars
-    assert_equal 'úüù', string
+    assert_equal "úüù", chars
+    assert_equal "úüù", string
   end
 
   def test_slice_should_throw_exceptions_on_invalid_arguments
@@ -442,48 +444,48 @@ class MultibyteCharsUTF8BehaviourTest < ActiveSupport::TestCase
   end
 
   def test_upcase_should_upcase_ascii_characters
-    assert_equal '', ''.mb_chars.upcase
-    assert_equal 'ABC', 'aBc'.mb_chars.upcase
+    assert_equal "", "".mb_chars.upcase
+    assert_equal "ABC", "aBc".mb_chars.upcase
   end
 
   def test_downcase_should_downcase_ascii_characters
-    assert_equal '', ''.mb_chars.downcase
-    assert_equal 'abc', 'aBc'.mb_chars.downcase
+    assert_equal "", "".mb_chars.downcase
+    assert_equal "abc", "aBc".mb_chars.downcase
   end
 
   def test_swapcase_should_swap_ascii_characters
-    assert_equal '', ''.mb_chars.swapcase
-    assert_equal 'AbC', 'aBc'.mb_chars.swapcase
+    assert_equal "", "".mb_chars.swapcase
+    assert_equal "AbC", "aBc".mb_chars.swapcase
   end
 
   def test_capitalize_should_work_on_ascii_characters
-    assert_equal '', ''.mb_chars.capitalize
-    assert_equal 'Abc', 'abc'.mb_chars.capitalize
+    assert_equal "", "".mb_chars.capitalize
+    assert_equal "Abc", "abc".mb_chars.capitalize
   end
 
   def test_titleize_should_work_on_ascii_characters
-    assert_equal '', ''.mb_chars.titleize
-    assert_equal 'Abc Abc', 'abc abc'.mb_chars.titleize
+    assert_equal "", "".mb_chars.titleize
+    assert_equal "Abc Abc", "abc abc".mb_chars.titleize
   end
 
   def test_respond_to_knows_which_methods_the_proxy_responds_to
-    assert ''.mb_chars.respond_to?(:slice) # Defined on Chars
-    assert ''.mb_chars.respond_to?(:capitalize!) # Defined on Chars
-    assert ''.mb_chars.respond_to?(:gsub) # Defined on String
-    assert !''.mb_chars.respond_to?(:undefined_method) # Not defined
+    assert "".mb_chars.respond_to?(:slice) # Defined on Chars
+    assert "".mb_chars.respond_to?(:capitalize!) # Defined on Chars
+    assert "".mb_chars.respond_to?(:gsub) # Defined on String
+    assert !"".mb_chars.respond_to?(:undefined_method) # Not defined
   end
 
   def test_method_works_for_proxyed_methods
-    assert_equal 'll', 'hello'.mb_chars.method(:slice).call(2..3) # Defined on Chars
-    chars = 'hello'.mb_chars
-    assert_equal 'Hello', chars.method(:capitalize!).call # Defined on Chars
-    assert_equal 'Hello', chars
-    assert_equal 'jello', 'hello'.mb_chars.method(:gsub).call(/h/, 'j') # Defined on String
-    assert_raise(NameError){ ''.mb_chars.method(:undefined_method) } # Not defined
+    assert_equal "ll", "hello".mb_chars.method(:slice).call(2..3) # Defined on Chars
+    chars = "hello".mb_chars
+    assert_equal "Hello", chars.method(:capitalize!).call # Defined on Chars
+    assert_equal "Hello", chars
+    assert_equal "jello", "hello".mb_chars.method(:gsub).call(/h/, "j") # Defined on String
+    assert_raise(NameError) { "".mb_chars.method(:undefined_method) } # Not defined
   end
 
   def test_acts_like_string
-    assert 'Bambi'.mb_chars.acts_like_string?
+    assert "Bambi".mb_chars.acts_like_string?
   end
 end
 
@@ -495,25 +497,25 @@ class MultibyteCharsExtrasTest < ActiveSupport::TestCase
 
   def test_upcase_should_be_unicode_aware
     assert_equal "АБВГД\0F", chars("аБвгд\0f").upcase
-    assert_equal 'こにちわ', chars('こにちわ').upcase
+    assert_equal "こにちわ", chars("こにちわ").upcase
   end
 
   def test_downcase_should_be_unicode_aware
     assert_equal "абвгд\0f", chars("аБвгд\0F").downcase
-    assert_equal 'こにちわ', chars('こにちわ').downcase
+    assert_equal "こにちわ", chars("こにちわ").downcase
   end
 
   def test_swapcase_should_be_unicode_aware
     assert_equal "аaéÜ\0f", chars("АAÉü\0F").swapcase
-    assert_equal 'こにちわ', chars('こにちわ').swapcase
+    assert_equal "こにちわ", chars("こにちわ").swapcase
   end
 
   def test_capitalize_should_be_unicode_aware
-    { 'аБвг аБвг' => 'Абвг абвг',
-      'аБвг АБВГ' => 'Абвг абвг',
-      'АБВГ АБВГ' => 'Абвг абвг',
-      '' => '' }.each do |f,t|
-        assert_equal t, chars(f).capitalize
+    { "аБвг аБвг" => "Абвг абвг",
+      "аБвг АБВГ" => "Абвг абвг",
+      "АБВГ АБВГ" => "Абвг абвг",
+      "" => "" }.each do |f, t|
+      assert_equal t, chars(f).capitalize
     end
   end
 
@@ -527,7 +529,7 @@ class MultibyteCharsExtrasTest < ActiveSupport::TestCase
   end
 
   def test_limit_should_not_break_on_blank_strings
-    example = chars('')
+    example = chars("")
     assert_equal example, example.limit(0)
     assert_equal example, example.limit(1)
   end
@@ -537,23 +539,23 @@ class MultibyteCharsExtrasTest < ActiveSupport::TestCase
     bytesize = UNICODE_STRING.bytesize
 
     assert_equal UNICODE_STRING, example.limit(bytesize)
-    assert_equal '', example.limit(0)
-    assert_equal '', example.limit(1)
-    assert_equal 'こ', example.limit(3)
-    assert_equal 'こに', example.limit(6)
-    assert_equal 'こに', example.limit(8)
-    assert_equal 'こにち', example.limit(9)
-    assert_equal 'こにちわ', example.limit(50)
+    assert_equal "", example.limit(0)
+    assert_equal "", example.limit(1)
+    assert_equal "こ", example.limit(3)
+    assert_equal "こに", example.limit(6)
+    assert_equal "こに", example.limit(8)
+    assert_equal "こにち", example.limit(9)
+    assert_equal "こにちわ", example.limit(50)
   end
 
   def test_limit_should_work_on_an_ascii_string
     ascii = chars(ASCII_STRING)
     assert_equal ASCII_STRING, ascii.limit(ASCII_STRING.length)
-    assert_equal '', ascii.limit(0)
-    assert_equal 'o', ascii.limit(1)
-    assert_equal 'oh', ascii.limit(2)
-    assert_equal 'ohay', ascii.limit(4)
-    assert_equal 'ohayo', ascii.limit(50)
+    assert_equal "", ascii.limit(0)
+    assert_equal "o", ascii.limit(1)
+    assert_equal "oh", ascii.limit(2)
+    assert_equal "ohay", ascii.limit(4)
+    assert_equal "ohayo", ascii.limit(50)
   end
 
   def test_limit_should_keep_under_the_specified_byte_limit
@@ -565,7 +567,7 @@ class MultibyteCharsExtrasTest < ActiveSupport::TestCase
 
   def test_composition_exclusion_is_set_up_properly
     # Normalization of DEVANAGARI LETTER QA breaks when composition exclusion isn't used correctly
-    qa = [0x915, 0x93c].pack('U*')
+    qa = [0x915, 0x93c].pack("U*")
     assert_equal qa, chars(qa).normalize(:c)
   end
 
@@ -575,7 +577,7 @@ class MultibyteCharsExtrasTest < ActiveSupport::TestCase
     [
       [0x0B47, 0x0300, 0x0B3E],
       [0x1100, 0x0300, 0x1161]
-    ].map { |c| c.pack('U*') }.each do |c|
+    ].map { |c| c.pack("U*") }.each do |c|
       assert_equal_codepoints c, chars(c).normalize(:c)
     end
   end
@@ -599,19 +601,19 @@ class MultibyteCharsExtrasTest < ActiveSupport::TestCase
       323 # COMBINING DOT BELOW
     ].pack("U*")
 
-    assert_equal_codepoints '', chars('').normalize
-    assert_equal_codepoints [44,105,106,328,323].pack("U*"), chars(comp_str).normalize(:kc).to_s
-    assert_equal_codepoints [44,307,328,323].pack("U*"), chars(comp_str).normalize(:c).to_s
-    assert_equal_codepoints [44,307,110,780,78,769].pack("U*"), chars(comp_str).normalize(:d).to_s
-    assert_equal_codepoints [44,105,106,110,780,78,769].pack("U*"), chars(comp_str).normalize(:kd).to_s
+    assert_equal_codepoints "", chars("").normalize
+    assert_equal_codepoints [44, 105, 106, 328, 323].pack("U*"), chars(comp_str).normalize(:kc).to_s
+    assert_equal_codepoints [44, 307, 328, 323].pack("U*"), chars(comp_str).normalize(:c).to_s
+    assert_equal_codepoints [44, 307, 110, 780, 78, 769].pack("U*"), chars(comp_str).normalize(:d).to_s
+    assert_equal_codepoints [44, 105, 106, 110, 780, 78, 769].pack("U*"), chars(comp_str).normalize(:kd).to_s
   end
 
   def test_should_compute_grapheme_length
     [
-      ['', 0],
-      ['abc', 3],
-      ['こにちわ', 4],
-      [[0x0924, 0x094D, 0x0930].pack('U*'), 2],
+      ["", 0],
+      ["abc", 3],
+      ["こにちわ", 4],
+      [[0x0924, 0x094D, 0x0930].pack("U*"), 2],
       # GB3
       [%w(cr lf), 1],
       # GB4
@@ -664,7 +666,6 @@ class MultibyteCharsExtrasTest < ActiveSupport::TestCase
   end
 
   def test_tidy_bytes_should_tidy_bytes
-
     single_byte_cases = {
       "\x21" => "!",   # Valid ASCII byte, low
       "\x41" => "A",   # Valid ASCII byte, mid
@@ -699,9 +700,9 @@ class MultibyteCharsExtrasTest < ActiveSupport::TestCase
     end
 
     byte_string = "\270\236\010\210\245"
-    tidy_string = [0xb8, 0x17e, 0x8, 0x2c6, 0xa5].pack('U*')
+    tidy_string = [0xb8, 0x17e, 0x8, 0x2c6, 0xa5].pack("U*")
     assert_equal_codepoints tidy_string, chars(byte_string).tidy_bytes
-    assert_nothing_raised { chars(byte_string).tidy_bytes.to_s.unpack('U*') }
+    assert_nothing_raised { chars(byte_string).tidy_bytes.to_s.unpack("U*") }
 
     # UTF-8 leading byte followed by too few continuation bytes
     assert_equal_codepoints "\xc3\xb0\xc2\xa5\xc2\xa4\x21", chars("\xf0\xa5\xa4\x21").tidy_bytes
@@ -720,16 +721,16 @@ class MultibyteCharsExtrasTest < ActiveSupport::TestCase
 
   private
 
-  def string_from_classes(classes)
-    # Characters from the character classes as described in UAX #29
-    character_from_class = {
-      :l => 0x1100, :v => 0x1160, :t => 0x11A8, :lv => 0xAC00, :lvt => 0xAC01, :cr => 0x000D, :lf => 0x000A,
-      :extend => 0x094D, :n => 0x64, :spacingmark => 0x0903, :r => 0x1F1E6, :control => 0x0001
-    }
-    classes.collect do |k|
-      character_from_class[k.intern]
-    end.pack('U*')
-  end
+    def string_from_classes(classes)
+      # Characters from the character classes as described in UAX #29
+      character_from_class = {
+        l: 0x1100, v: 0x1160, t: 0x11A8, lv: 0xAC00, lvt: 0xAC01, cr: 0x000D, lf: 0x000A,
+        extend: 0x094D, n: 0x64, spacingmark: 0x0903, r: 0x1F1E6, control: 0x0001
+      }
+      classes.collect do |k|
+        character_from_class[k.intern]
+      end.pack("U*")
+    end
 end
 
 class MultibyteInternalsTest < ActiveSupport::TestCase
diff --git a/activesupport/test/multibyte_conformance_test.rb b/activesupport/test/multibyte_conformance_test.rb
index 9fca47a985..748e8d16e1 100644
--- a/activesupport/test/multibyte_conformance_test.rb
+++ b/activesupport/test/multibyte_conformance_test.rb
@@ -1,34 +1,16 @@
-require 'abstract_unit'
-require 'multibyte_test_helpers'
+# frozen_string_literal: true
 
-require 'fileutils'
-require 'open-uri'
-require 'tmpdir'
+require "abstract_unit"
+require "multibyte_test_helpers"
 
-class MultibyteConformanceTest < ActiveSupport::TestCase
-  class Downloader
-    def self.download(from, to)
-      unless File.exist?(to)
-        unless File.exist?(File.dirname(to))
-          system "mkdir -p #{File.dirname(to)}"
-        end
-        open(from) do |source|
-          File.open(to, 'w') do |target|
-            source.each_line do |l|
-              target.write l
-            end
-          end
-        end
-      end
-      true
-    end
-  end
+require "fileutils"
+require "open-uri"
+require "tmpdir"
 
+class MultibyteConformanceTest < ActiveSupport::TestCase
   include MultibyteTestHelpers
 
-  UNIDATA_URL = "http://www.unicode.org/Public/#{ActiveSupport::Multibyte::Unicode::UNICODE_VERSION}/ucd"
-  UNIDATA_FILE = '/NormalizationTest.txt'
-  CACHE_DIR = "#{Dir.tmpdir}/cache/unicode_conformance"
+  UNIDATA_FILE = "/NormalizationTest.txt"
   FileUtils.mkdir_p(CACHE_DIR)
   RUN_P = begin
             Downloader.download(UNIDATA_URL + UNIDATA_FILE, CACHE_DIR + UNIDATA_FILE)
@@ -102,19 +84,19 @@ class MultibyteConformanceTest < ActiveSupport::TestCase
     end
   end
 
-  protected
+  private
     def each_line_of_norm_tests(&block)
-      File.open(File.join(CACHE_DIR, UNIDATA_FILE), 'r') do | f |
+      File.open(File.join(CACHE_DIR, UNIDATA_FILE), "r") do | f |
         until f.eof?
           line = f.gets.chomp!
-          next if (line.empty? || line =~ /^\#/)
+          next if line.empty? || line.start_with?("#")
 
           cols, comment = line.split("#")
           cols = cols.split(";").map(&:strip).reject(&:empty?)
           next unless cols.length == 5
 
           # codepoints are in hex in the test suite, pack wants them as integers
-          cols.map!{|c| c.split.map{|codepoint| codepoint.to_i(16)}.pack("U*") }
+          cols.map! { |c| c.split.map { |codepoint| codepoint.to_i(16) }.pack("U*") }
           cols << comment
 
           yield(*cols)
@@ -123,6 +105,6 @@ class MultibyteConformanceTest < ActiveSupport::TestCase
     end
 
     def inspect_codepoints(str)
-      str.to_s.unpack("U*").map{|cp| cp.to_s(16) }.join(' ')
+      str.to_s.unpack("U*").map { |cp| cp.to_s(16) }.join(" ")
     end
 end
diff --git a/activesupport/test/multibyte_grapheme_break_conformance_test.rb b/activesupport/test/multibyte_grapheme_break_conformance_test.rb
index 6e2f02abed..fac74cd80f 100644
--- a/activesupport/test/multibyte_grapheme_break_conformance_test.rb
+++ b/activesupport/test/multibyte_grapheme_break_conformance_test.rb
@@ -1,37 +1,23 @@
-# encoding: utf-8
+# frozen_string_literal: true
 
-require 'abstract_unit'
+require "abstract_unit"
+require "multibyte_test_helpers"
 
-require 'fileutils'
-require 'open-uri'
-require 'tmpdir'
+require "fileutils"
+require "open-uri"
+require "tmpdir"
 
 class MultibyteGraphemeBreakConformanceTest < ActiveSupport::TestCase
-  class Downloader
-    def self.download(from, to)
-      unless File.exist?(to)
-        $stderr.puts "Downloading #{from} to #{to}"
-        unless File.exist?(File.dirname(to))
-          system "mkdir -p #{File.dirname(to)}"
-        end
-        open(from) do |source|
-          File.open(to, 'w') do |target|
-            source.each_line do |l|
-              target.write l
-            end
-          end
-        end
-      end
-    end
-  end
+  include MultibyteTestHelpers
 
-  TEST_DATA_URL = "http://www.unicode.org/Public/#{ActiveSupport::Multibyte::Unicode::UNICODE_VERSION}/ucd/auxiliary"
-  TEST_DATA_FILE = '/GraphemeBreakTest.txt'
-  CACHE_DIR = "#{Dir.tmpdir}/cache/unicode_conformance"
+  UNIDATA_FILE = "/auxiliary/GraphemeBreakTest.txt"
+  RUN_P = begin
+            Downloader.download(UNIDATA_URL + UNIDATA_FILE, CACHE_DIR + UNIDATA_FILE)
+          rescue
+          end
 
   def setup
-    FileUtils.mkdir_p(CACHE_DIR)
-    Downloader.download(TEST_DATA_URL + TEST_DATA_FILE, CACHE_DIR + TEST_DATA_FILE)
+    skip "Unable to download test data" unless RUN_P
   end
 
   def test_breaks
@@ -42,24 +28,24 @@ class MultibyteGraphemeBreakConformanceTest < ActiveSupport::TestCase
     end
   end
 
-  protected
+  private
     def each_line_of_break_tests(&block)
       lines = 0
       max_test_lines = 0 # Don't limit below 21, because that's the header of the testfile
-      File.open(File.join(CACHE_DIR, TEST_DATA_FILE), 'r') do | f |
-        until f.eof? || (max_test_lines > 21 and lines > max_test_lines)
+      File.open(File.join(CACHE_DIR, UNIDATA_FILE), "r") do | f |
+        until f.eof? || (max_test_lines > 21 && lines > max_test_lines)
           lines += 1
           line = f.gets.chomp!
-          next if (line.empty? || line =~ /^\#/)
+          next if line.empty? || line.start_with?("#")
 
           cols, comment = line.split("#")
           # Cluster breaks are represented by ÷
-          clusters = cols.split("÷").map{|e| e.strip}.reject{|e| e.empty? }
+          clusters = cols.split("÷").map { |e| e.strip }.reject { |e| e.empty? }
           clusters = clusters.map do |cluster|
             # Codepoints within each cluster are separated by ×
-            codepoints = cluster.split("×").map{|e| e.strip}.reject{|e| e.empty? }
+            codepoints = cluster.split("×").map { |e| e.strip }.reject { |e| e.empty? }
             # codepoints are in hex in the test suite, pack wants them as integers
-            codepoints.map{|codepoint| codepoint.to_i(16)}
+            codepoints.map { |codepoint| codepoint.to_i(16) }
           end
 
           # The tests contain a solitary U+D800 <Non Private Use High
diff --git a/activesupport/test/multibyte_normalization_conformance_test.rb b/activesupport/test/multibyte_normalization_conformance_test.rb
index 0d31c9520f..1173a94e81 100644
--- a/activesupport/test/multibyte_normalization_conformance_test.rb
+++ b/activesupport/test/multibyte_normalization_conformance_test.rb
@@ -1,41 +1,24 @@
-# encoding: utf-8
+# frozen_string_literal: true
 
-require 'abstract_unit'
-require 'multibyte_test_helpers'
+require "abstract_unit"
+require "multibyte_test_helpers"
 
-require 'fileutils'
-require 'open-uri'
-require 'tmpdir'
+require "fileutils"
+require "open-uri"
+require "tmpdir"
 
 class MultibyteNormalizationConformanceTest < ActiveSupport::TestCase
-  class Downloader
-    def self.download(from, to)
-      unless File.exist?(to)
-        $stderr.puts "Downloading #{from} to #{to}"
-        unless File.exist?(File.dirname(to))
-          system "mkdir -p #{File.dirname(to)}"
-        end
-        open(from) do |source|
-          File.open(to, 'w') do |target|
-            source.each_line do |l|
-              target.write l
-            end
-          end
-        end
-      end
-    end
-  end
-
   include MultibyteTestHelpers
 
-  UNIDATA_URL = "http://www.unicode.org/Public/#{ActiveSupport::Multibyte::Unicode::UNICODE_VERSION}/ucd"
-  UNIDATA_FILE = '/NormalizationTest.txt'
-  CACHE_DIR = "#{Dir.tmpdir}/cache/unicode_conformance"
+  UNIDATA_FILE = "/NormalizationTest.txt"
+  RUN_P = begin
+            Downloader.download(UNIDATA_URL + UNIDATA_FILE, CACHE_DIR + UNIDATA_FILE)
+          rescue
+          end
 
   def setup
-    FileUtils.mkdir_p(CACHE_DIR)
-    Downloader.download(UNIDATA_URL + UNIDATA_FILE, CACHE_DIR + UNIDATA_FILE)
     @proxy = ActiveSupport::Multibyte::Chars
+    skip "Unable to download test data" unless RUN_P
   end
 
   def test_normalizations_C
@@ -100,22 +83,22 @@ class MultibyteNormalizationConformanceTest < ActiveSupport::TestCase
     end
   end
 
-  protected
+  private
     def each_line_of_norm_tests(&block)
       lines = 0
       max_test_lines = 0 # Don't limit below 38, because that's the header of the testfile
-      File.open(File.join(CACHE_DIR, UNIDATA_FILE), 'r') do | f |
-        until f.eof? || (max_test_lines > 38 and lines > max_test_lines)
+      File.open(File.join(CACHE_DIR, UNIDATA_FILE), "r") do | f |
+        until f.eof? || (max_test_lines > 38 && lines > max_test_lines)
           lines += 1
           line = f.gets.chomp!
-          next if (line.empty? || line =~ /^\#/)
+          next if line.empty? || line.start_with?("#")
 
           cols, comment = line.split("#")
-          cols = cols.split(";").map{|e| e.strip}.reject{|e| e.empty? }
+          cols = cols.split(";").map { |e| e.strip }.reject { |e| e.empty? }
           next unless cols.length == 5
 
           # codepoints are in hex in the test suite, pack wants them as integers
-          cols.map!{|c| c.split.map{|codepoint| codepoint.to_i(16)}.pack("U*") }
+          cols.map! { |c| c.split.map { |codepoint| codepoint.to_i(16) }.pack("U*") }
           cols << comment
 
           yield(*cols)
@@ -124,6 +107,6 @@ class MultibyteNormalizationConformanceTest < ActiveSupport::TestCase
     end
 
     def inspect_codepoints(str)
-      str.to_s.unpack("U*").map{|cp| cp.to_s(16) }.join(' ')
+      str.to_s.unpack("U*").map { |cp| cp.to_s(16) }.join(" ")
     end
 end
diff --git a/activesupport/test/multibyte_proxy_test.rb b/activesupport/test/multibyte_proxy_test.rb
index 360cf57302..ecedab2569 100644
--- a/activesupport/test/multibyte_proxy_test.rb
+++ b/activesupport/test/multibyte_proxy_test.rb
@@ -1,4 +1,6 @@
-require 'abstract_unit'
+# frozen_string_literal: true
+
+require "abstract_unit"
 
 class MultibyteProxyText < ActiveSupport::TestCase
   class AsciiOnlyEncoder
@@ -6,7 +8,7 @@ class MultibyteProxyText < ActiveSupport::TestCase
     alias to_s wrapped_string
 
     def initialize(string)
-      @wrapped_string = string.gsub(/[^\u0000-\u007F]/, '?')
+      @wrapped_string = string.gsub(/[^\u0000-\u007F]/, "?")
     end
   end
 
diff --git a/activesupport/test/multibyte_test_helpers.rb b/activesupport/test/multibyte_test_helpers.rb
index 58cf5488cd..f7cf993100 100644
--- a/activesupport/test/multibyte_test_helpers.rb
+++ b/activesupport/test/multibyte_test_helpers.rb
@@ -1,17 +1,41 @@
+# frozen_string_literal: true
+
 module MultibyteTestHelpers
-  UNICODE_STRING = 'こにちわ'.freeze
-  ASCII_STRING = 'ohayo'.freeze
-  BYTE_STRING = "\270\236\010\210\245".force_encoding("ASCII-8BIT").freeze
+  class Downloader
+    def self.download(from, to)
+      unless File.exist?(to)
+        unless File.exist?(File.dirname(to))
+          system "mkdir -p #{File.dirname(to)}"
+        end
+        open(from) do |source|
+          File.open(to, "w") do |target|
+            source.each_line do |l|
+              target.write l
+            end
+          end
+        end
+      end
+      true
+    end
+  end
+
+  UNIDATA_URL = "http://www.unicode.org/Public/#{ActiveSupport::Multibyte::Unicode::UNICODE_VERSION}/ucd"
+  CACHE_DIR = "#{Dir.tmpdir}/cache/unicode_conformance/#{ActiveSupport::Multibyte::Unicode::UNICODE_VERSION}"
+  FileUtils.mkdir_p(CACHE_DIR)
+
+  UNICODE_STRING = "こにちわ".freeze
+  ASCII_STRING = "ohayo".freeze
+  BYTE_STRING = "\270\236\010\210\245".dup.force_encoding("ASCII-8BIT").freeze
 
   def chars(str)
     ActiveSupport::Multibyte::Chars.new(str)
   end
 
   def inspect_codepoints(str)
-    str.to_s.unpack("U*").map{|cp| cp.to_s(16) }.join(' ')
+    str.to_s.unpack("U*").map { |cp| cp.to_s(16) }.join(" ")
   end
 
-  def assert_equal_codepoints(expected, actual, message=nil)
+  def assert_equal_codepoints(expected, actual, message = nil)
     assert_equal(inspect_codepoints(expected), inspect_codepoints(actual), message)
   end
 end
diff --git a/activesupport/test/multibyte_unicode_database_test.rb b/activesupport/test/multibyte_unicode_database_test.rb
index dd33641ec2..540a34493d 100644
--- a/activesupport/test/multibyte_unicode_database_test.rb
+++ b/activesupport/test/multibyte_unicode_database_test.rb
@@ -1,8 +1,8 @@
-require 'abstract_unit'
+# frozen_string_literal: true
 
+require "abstract_unit"
 
 class MultibyteUnicodeDatabaseTest < ActiveSupport::TestCase
-
   include ActiveSupport::Multibyte::Unicode
 
   def setup
diff --git a/activesupport/test/notifications/evented_notification_test.rb b/activesupport/test/notifications/evented_notification_test.rb
index f690ad43fc..4beb8194b9 100644
--- a/activesupport/test/notifications/evented_notification_test.rb
+++ b/activesupport/test/notifications/evented_notification_test.rb
@@ -1,4 +1,6 @@
-require 'abstract_unit'
+# frozen_string_literal: true
+
+require "abstract_unit"
 
 module ActiveSupport
   module Notifications
@@ -7,7 +9,7 @@ module ActiveSupport
         attr_reader :events
 
         def initialize
-          @events   = []
+          @events = []
         end
 
         def start(name, id, payload)
@@ -28,26 +30,26 @@ module ActiveSupport
       def test_evented_listener
         notifier = Fanout.new
         listener = Listener.new
-        notifier.subscribe 'hi', listener
-        notifier.start  'hi', 1, {}
-        notifier.start  'hi', 2, {}
-        notifier.finish 'hi', 2, {}
-        notifier.finish 'hi', 1, {}
+        notifier.subscribe "hi", listener
+        notifier.start  "hi", 1, {}
+        notifier.start  "hi", 2, {}
+        notifier.finish "hi", 2, {}
+        notifier.finish "hi", 1, {}
 
         assert_equal 4, listener.events.length
         assert_equal [
-          [:start, 'hi', 1, {}],
-          [:start, 'hi', 2, {}],
-          [:finish, 'hi', 2, {}],
-          [:finish, 'hi', 1, {}],
+          [:start, "hi", 1, {}],
+          [:start, "hi", 2, {}],
+          [:finish, "hi", 2, {}],
+          [:finish, "hi", 1, {}],
         ], listener.events
       end
 
       def test_evented_listener_no_events
         notifier = Fanout.new
         listener = Listener.new
-        notifier.subscribe 'hi', listener
-        notifier.start  'world', 1, {}
+        notifier.subscribe "hi", listener
+        notifier.start  "world", 1, {}
         assert_equal 0, listener.events.length
       end
 
@@ -55,31 +57,31 @@ module ActiveSupport
         notifier = Fanout.new
         listener = Listener.new
         notifier.subscribe nil, listener
-        notifier.start  'hello', 1, {}
-        notifier.start  'world', 1, {}
-        notifier.finish  'world', 1, {}
-        notifier.finish  'hello', 1, {}
+        notifier.start  "hello", 1, {}
+        notifier.start  "world", 1, {}
+        notifier.finish  "world", 1, {}
+        notifier.finish  "hello", 1, {}
 
         assert_equal 4, listener.events.length
         assert_equal [
-          [:start,  'hello', 1, {}],
-          [:start,  'world', 1, {}],
-          [:finish,  'world', 1, {}],
-          [:finish,  'hello', 1, {}],
+          [:start,  "hello", 1, {}],
+          [:start,  "world", 1, {}],
+          [:finish,  "world", 1, {}],
+          [:finish,  "hello", 1, {}],
         ], listener.events
       end
 
       def test_evented_listener_priority
         notifier = Fanout.new
         listener = ListenerWithTimedSupport.new
-        notifier.subscribe 'hi', listener
+        notifier.subscribe "hi", listener
 
-        notifier.start 'hi', 1, {}
-        notifier.finish 'hi', 1, {}
+        notifier.start "hi", 1, {}
+        notifier.finish "hi", 1, {}
 
         assert_equal [
-          [:start, 'hi', 1, {}],
-          [:finish, 'hi', 1, {}]
+          [:start, "hi", 1, {}],
+          [:finish, "hi", 1, {}]
         ], listener.events
       end
     end
diff --git a/activesupport/test/notifications/instrumenter_test.rb b/activesupport/test/notifications/instrumenter_test.rb
index f46e96f636..1d76c91d30 100644
--- a/activesupport/test/notifications/instrumenter_test.rb
+++ b/activesupport/test/notifications/instrumenter_test.rb
@@ -1,5 +1,7 @@
-require 'abstract_unit'
-require 'active_support/notifications/instrumenter'
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "active_support/notifications/instrumenter"
 
 module ActiveSupport
   module Notifications
@@ -22,11 +24,11 @@ module ActiveSupport
         super
         @notifier     = TestNotifier.new
         @instrumenter = Instrumenter.new @notifier
-        @payload      =  { :foo => Object.new }
+        @payload = { foo: Object.new }
       end
 
       def test_instrument
-        called  = false
+        called = false
         instrumenter.instrument("foo", payload) {
           called = true
         }
@@ -39,7 +41,7 @@ module ActiveSupport
         assert_equal 1, notifier.finishes.size
         name, _, payload = notifier.finishes.first
         assert_equal "awesome", name
-        assert_equal Hash[:result => 2], payload
+        assert_equal Hash[result: 2], payload
       end
 
       def test_start
diff --git a/activesupport/test/notifications_test.rb b/activesupport/test/notifications_test.rb
index 1cb17e6197..5cfbd60131 100644
--- a/activesupport/test/notifications_test.rb
+++ b/activesupport/test/notifications_test.rb
@@ -1,5 +1,7 @@
-require 'abstract_unit'
-require 'active_support/core_ext/module/delegation'
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "active_support/core_ext/module/delegation"
 
 module Notifications
   class TestCase < ActiveSupport::TestCase
@@ -31,7 +33,7 @@ module Notifications
       expected = [name, name]
 
       events   = []
-      callback = lambda {|*_| events << _.first}
+      callback = lambda { |*_| events << _.first }
       ActiveSupport::Notifications.subscribed(callback, name) do
         ActiveSupport::Notifications.instrument(name)
         ActiveSupport::Notifications.instrument(name2)
@@ -49,10 +51,10 @@ module Notifications
       old_notifier = ActiveSupport::Notifications.notifier
       ActiveSupport::Notifications.notifier = ActiveSupport::Notifications::Fanout.new
 
-      ActiveSupport::Notifications.subscribe('foo', TestSubscriber.new)
+      ActiveSupport::Notifications.subscribe("foo", TestSubscriber.new)
 
-      ActiveSupport::Notifications.instrument('foo') do
-        ActiveSupport::Notifications.subscribe('foo') {}
+      ActiveSupport::Notifications.instrument("foo") do
+        ActiveSupport::Notifications.subscribe("foo") {}
       end
     ensure
       ActiveSupport::Notifications.notifier = old_notifier
@@ -141,26 +143,26 @@ module Notifications
 
     def test_log_subscriber_with_string
       events = []
-      @notifier.subscribe('1') { |*args| events << args }
+      @notifier.subscribe("1") { |*args| events << args }
 
-      @notifier.publish '1'
-      @notifier.publish '1.a'
-      @notifier.publish 'a.1'
+      @notifier.publish "1"
+      @notifier.publish "1.a"
+      @notifier.publish "a.1"
       @notifier.wait
 
-      assert_equal [['1']], events
+      assert_equal [["1"]], events
     end
 
     def test_log_subscriber_with_pattern
       events = []
       @notifier.subscribe(/\d/) { |*args| events << args }
 
-      @notifier.publish '1'
-      @notifier.publish 'a.1'
-      @notifier.publish '1.a'
+      @notifier.publish "1"
+      @notifier.publish "a.1"
+      @notifier.publish "1.a"
       @notifier.wait
 
-      assert_equal [['1'], ['a.1'], ['1.a']], events
+      assert_equal [["1"], ["a.1"], ["1.a"]], events
     end
 
     def test_multiple_log_subscribers
@@ -188,7 +190,7 @@ module Notifications
   end
 
   class InstrumentationTest < TestCase
-    delegate :instrument, :to => ActiveSupport::Notifications
+    delegate :instrument, to: ActiveSupport::Notifications
 
     def test_instrument_returns_block_result
       assert_equal 2, instrument(:awesome) { 1 + 1 }
@@ -198,7 +200,7 @@ module Notifications
       assert_equal 2, instrument(:awesome) { |p| p[:result] = 1 + 1 }
       assert_equal 1, @events.size
       assert_equal :awesome, @events.first.name
-      assert_equal Hash[:result => 2], @events.first.payload
+      assert_equal Hash[result: 2], @events.first.payload
     end
 
     def test_instrumenter_exposes_its_id
@@ -206,24 +208,24 @@ module Notifications
     end
 
     def test_nested_events_can_be_instrumented
-      instrument(:awesome, :payload => "notifications") do
-        instrument(:wot, :payload => "child") do
+      instrument(:awesome, payload: "notifications") do
+        instrument(:wot, payload: "child") do
           1 + 1
         end
 
         assert_equal 1, @events.size
         assert_equal :wot, @events.first.name
-        assert_equal Hash[:payload => "child"], @events.first.payload
+        assert_equal Hash[payload: "child"], @events.first.payload
       end
 
       assert_equal 2, @events.size
       assert_equal :awesome, @events.last.name
-      assert_equal Hash[:payload => "notifications"], @events.last.payload
+      assert_equal Hash[payload: "notifications"], @events.last.payload
     end
 
     def test_instrument_publishes_when_exception_is_raised
       begin
-        instrument(:awesome, :payload => "notifications") do
+        instrument(:awesome, payload: "notifications") do
           raise "FAIL"
         end
       rescue RuntimeError => e
@@ -231,15 +233,15 @@ module Notifications
       end
 
       assert_equal 1, @events.size
-      assert_equal Hash[:payload => "notifications",
-        :exception => ["RuntimeError", "FAIL"], :exception_object => e], @events.last.payload
+      assert_equal Hash[payload: "notifications",
+        exception: ["RuntimeError", "FAIL"], exception_object: e], @events.last.payload
     end
 
     def test_event_is_pushed_even_without_block
-      instrument(:awesome, :payload => "notifications")
+      instrument(:awesome, payload: "notifications")
       assert_equal 1, @events.size
       assert_equal :awesome, @events.last.name
-      assert_equal Hash[:payload => "notifications"], @events.last.payload
+      assert_equal Hash[payload: "notifications"], @events.last.payload
     end
   end
 
@@ -254,8 +256,8 @@ module Notifications
     end
 
     def test_events_consumes_information_given_as_payload
-      event = event(:foo, Time.now, Time.now + 1, random_id, :payload => :bar)
-      assert_equal Hash[:payload => :bar], event.payload
+      event = event(:foo, Time.now, Time.now + 1, random_id, payload: :bar)
+      assert_equal Hash[payload: :bar], event.payload
     end
 
     def test_event_is_parent_based_on_children
@@ -273,7 +275,7 @@ module Notifications
       assert !not_child.parent_of?(parent)
     end
 
-    protected
+    private
       def random_id
         @random_id ||= SecureRandom.hex(10)
       end
diff --git a/activesupport/test/number_helper_i18n_test.rb b/activesupport/test/number_helper_i18n_test.rb
index e6925e9083..365fa96f4d 100644
--- a/activesupport/test/number_helper_i18n_test.rb
+++ b/activesupport/test/number_helper_i18n_test.rb
@@ -1,46 +1,49 @@
-require 'abstract_unit'
-require 'active_support/number_helper'
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "active_support/number_helper"
+require "active_support/core_ext/hash/keys"
 
 module ActiveSupport
   class NumberHelperI18nTest < ActiveSupport::TestCase
     include ActiveSupport::NumberHelper
 
     def setup
-      I18n.backend.store_translations 'ts',
-        :number => {
-        :format => { :precision => 3, :delimiter => ',', :separator => '.', :significant => false, :strip_insignificant_zeros => false },
-        :currency => { :format => { :unit => '&$', :format => '%u - %n', :negative_format => '(%u - %n)', :precision => 2 } },
-        :human => {
-          :format => {
-            :precision => 2,
-            :significant => true,
-            :strip_insignificant_zeros => true
+      I18n.backend.store_translations "ts",
+        number: {
+        format: { precision: 3, delimiter: ",", separator: ".", significant: false, strip_insignificant_zeros: false },
+        currency: { format: { unit: "&$", format: "%u - %n", negative_format: "(%u - %n)", precision: 2 } },
+        human: {
+          format: {
+            precision: 2,
+            significant: true,
+            strip_insignificant_zeros: true
           },
-          :storage_units => {
-            :format => "%n %u",
-            :units => {
-              :byte => "b",
-              :kb => "k"
+          storage_units: {
+            format: "%n %u",
+            units: {
+              byte: "b",
+              kb: "k"
             }
           },
-          :decimal_units => {
-            :format => "%n %u",
-            :units => {
-              :deci => {:one => "Tenth", :other => "Tenths"},
-              :unit =>  "u",
-              :ten => {:one => "Ten", :other => "Tens"},
-              :thousand => "t",
-              :million => "m",
-              :billion =>"b",
-              :trillion =>"t" ,
-              :quadrillion =>"q"
+          decimal_units: {
+            format: "%n %u",
+            units: {
+              deci: { one: "Tenth", other: "Tenths" },
+              unit: "u",
+              ten: { one: "Ten", other: "Tens" },
+              thousand: "t",
+              million: "m",
+              billion: "b",
+              trillion: "t",
+              quadrillion: "q"
             }
           }
         },
-        :percentage => { :format => {:delimiter => '', :precision => 2, :strip_insignificant_zeros => true} },
-        :precision => { :format => {:delimiter => '', :significant => true} }
+        percentage: { format: { delimiter: "", precision: 2, strip_insignificant_zeros: true } },
+        precision: { format: { delimiter: "", significant: true } }
       },
-      :custom_units_for_number_to_human => {:mili => "mm", :centi => "cm", :deci => "dm", :unit => "m", :ten => "dam", :hundred => "hm", :thousand => "km"}
+      custom_units_for_number_to_human: { mili: "mm", centi: "cm", deci: "dm", unit: "m", ten: "dam", hundred: "hm", thousand: "km" }
     end
 
     def teardown
@@ -48,101 +51,101 @@ module ActiveSupport
     end
 
     def test_number_to_i18n_currency
-      assert_equal("&$ - 10.00", number_to_currency(10, :locale => 'ts'))
-      assert_equal("(&$ - 10.00)", number_to_currency(-10, :locale => 'ts'))
-      assert_equal("-10.00 - &$", number_to_currency(-10, :locale => 'ts', :format => "%n - %u"))
+      assert_equal("&$ - 10.00", number_to_currency(10, locale: "ts"))
+      assert_equal("(&$ - 10.00)", number_to_currency(-10, locale: "ts"))
+      assert_equal("-10.00 - &$", number_to_currency(-10, locale: "ts", format: "%n - %u"))
     end
 
     def test_number_to_currency_with_empty_i18n_store
-      assert_equal("$10.00", number_to_currency(10, :locale => 'empty'))
-      assert_equal("-$10.00", number_to_currency(-10, :locale => 'empty'))
+      assert_equal("$10.00", number_to_currency(10, locale: "empty"))
+      assert_equal("-$10.00", number_to_currency(-10, locale: "empty"))
     end
 
     def test_locale_default_format_has_precedence_over_helper_defaults
-      I18n.backend.store_translations 'ts',
-        { :number => { :format => { :separator => ";" } } }
+      I18n.backend.store_translations "ts",
+        number: { format: { separator: ";" } }
 
-      assert_equal("&$ - 10;00", number_to_currency(10, :locale => 'ts'))
+      assert_equal("&$ - 10;00", number_to_currency(10, locale: "ts"))
     end
 
     def test_number_to_currency_without_currency_negative_format
-      I18n.backend.store_translations 'no_negative_format', :number => {
-        :currency => { :format => { :unit => '@', :format => '%n %u' } }
+      I18n.backend.store_translations "no_negative_format", number: {
+        currency: { format: { unit: "@", format: "%n %u" } }
       }
 
-      assert_equal("-10.00 @", number_to_currency(-10, :locale => 'no_negative_format'))
+      assert_equal("-10.00 @", number_to_currency(-10, locale: "no_negative_format"))
     end
 
     def test_number_with_i18n_precision
-      #Delimiter was set to ""
-      assert_equal("10000", number_to_rounded(10000, :locale => 'ts'))
+      # Delimiter was set to ""
+      assert_equal("10000", number_to_rounded(10000, locale: "ts"))
 
-      #Precision inherited and significant was set
-      assert_equal("1.00", number_to_rounded(1.0, :locale => 'ts'))
+      # Precision inherited and significant was set
+      assert_equal("1.00", number_to_rounded(1.0, locale: "ts"))
     end
 
     def test_number_with_i18n_precision_and_empty_i18n_store
-      assert_equal("123456789.123", number_to_rounded(123456789.123456789, :locale => 'empty'))
-      assert_equal("1.000", number_to_rounded(1.0000, :locale => 'empty'))
+      assert_equal("123456789.123", number_to_rounded(123456789.123456789, locale: "empty"))
+      assert_equal("1.000", number_to_rounded(1.0000, locale: "empty"))
     end
 
     def test_number_with_i18n_delimiter
-      #Delimiter "," and separator "."
-      assert_equal("1,000,000.234", number_to_delimited(1000000.234, :locale => 'ts'))
+      # Delimiter "," and separator "."
+      assert_equal("1,000,000.234", number_to_delimited(1000000.234, locale: "ts"))
     end
 
     def test_number_with_i18n_delimiter_and_empty_i18n_store
-      assert_equal("1,000,000.234", number_to_delimited(1000000.234, :locale => 'empty'))
+      assert_equal("1,000,000.234", number_to_delimited(1000000.234, locale: "empty"))
     end
 
     def test_number_to_i18n_percentage
       # to see if strip_insignificant_zeros is true
-      assert_equal("1%", number_to_percentage(1, :locale => 'ts'))
+      assert_equal("1%", number_to_percentage(1, locale: "ts"))
       # precision is 2, significant should be inherited
-      assert_equal("1.24%", number_to_percentage(1.2434, :locale => 'ts'))
+      assert_equal("1.24%", number_to_percentage(1.2434, locale: "ts"))
       # no delimiter
-      assert_equal("12434%", number_to_percentage(12434, :locale => 'ts'))
+      assert_equal("12434%", number_to_percentage(12434, locale: "ts"))
     end
 
     def test_number_to_i18n_percentage_and_empty_i18n_store
-      assert_equal("1.000%", number_to_percentage(1, :locale => 'empty'))
-      assert_equal("1.243%", number_to_percentage(1.2434, :locale => 'empty'))
-      assert_equal("12434.000%", number_to_percentage(12434, :locale => 'empty'))
+      assert_equal("1.000%", number_to_percentage(1, locale: "empty"))
+      assert_equal("1.243%", number_to_percentage(1.2434, locale: "empty"))
+      assert_equal("12434.000%", number_to_percentage(12434, locale: "empty"))
     end
 
     def test_number_to_i18n_human_size
-      #b for bytes and k for kbytes
-      assert_equal("2 k", number_to_human_size(2048, :locale => 'ts'))
-      assert_equal("42 b", number_to_human_size(42, :locale => 'ts'))
+      # b for bytes and k for kbytes
+      assert_equal("2 k", number_to_human_size(2048, locale: "ts"))
+      assert_equal("42 b", number_to_human_size(42, locale: "ts"))
     end
 
     def test_number_to_i18n_human_size_with_empty_i18n_store
-      assert_equal("2 KB", number_to_human_size(2048, :locale => 'empty'))
-      assert_equal("42 Bytes", number_to_human_size(42, :locale => 'empty'))
+      assert_equal("2 KB", number_to_human_size(2048, locale: "empty"))
+      assert_equal("42 Bytes", number_to_human_size(42, locale: "empty"))
     end
 
     def test_number_to_human_with_default_translation_scope
-      #Using t for thousand
-      assert_equal "2 t", number_to_human(2000, :locale => 'ts')
-      #Significant was set to true with precision 2, using b for billion
-      assert_equal "1.2 b", number_to_human(1234567890, :locale => 'ts')
-      #Using pluralization (Ten/Tens and Tenth/Tenths)
-      assert_equal "1 Tenth", number_to_human(0.1, :locale => 'ts')
-      assert_equal "1.3 Tenth", number_to_human(0.134, :locale => 'ts')
-      assert_equal "2 Tenths", number_to_human(0.2, :locale => 'ts')
-      assert_equal "1 Ten", number_to_human(10, :locale => 'ts')
-      assert_equal "1.2 Ten", number_to_human(12, :locale => 'ts')
-      assert_equal "2 Tens", number_to_human(20, :locale => 'ts')
+      # Using t for thousand
+      assert_equal "2 t", number_to_human(2000, locale: "ts")
+      # Significant was set to true with precision 2, using b for billion
+      assert_equal "1.2 b", number_to_human(1234567890, locale: "ts")
+      # Using pluralization (Ten/Tens and Tenth/Tenths)
+      assert_equal "1 Tenth", number_to_human(0.1, locale: "ts")
+      assert_equal "1.3 Tenth", number_to_human(0.134, locale: "ts")
+      assert_equal "2 Tenths", number_to_human(0.2, locale: "ts")
+      assert_equal "1 Ten", number_to_human(10, locale: "ts")
+      assert_equal "1.2 Ten", number_to_human(12, locale: "ts")
+      assert_equal "2 Tens", number_to_human(20, locale: "ts")
     end
 
     def test_number_to_human_with_empty_i18n_store
-      assert_equal "2 Thousand", number_to_human(2000, :locale => 'empty')
-      assert_equal "1.23 Billion", number_to_human(1234567890, :locale => 'empty')
+      assert_equal "2 Thousand", number_to_human(2000, locale: "empty")
+      assert_equal "1.23 Billion", number_to_human(1234567890, locale: "empty")
     end
 
     def test_number_to_human_with_custom_translation_scope
-      #Significant was set to true with precision 2, with custom translated units
-      assert_equal "4.3 cm", number_to_human(0.0432, :locale => 'ts', :units => :custom_units_for_number_to_human)
+      # Significant was set to true with precision 2, with custom translated units
+      assert_equal "4.3 cm", number_to_human(0.0432, locale: "ts", units: :custom_units_for_number_to_human)
     end
   end
 end
diff --git a/activesupport/test/number_helper_test.rb b/activesupport/test/number_helper_test.rb
index 074c872efc..16ccc5572c 100644
--- a/activesupport/test/number_helper_test.rb
+++ b/activesupport/test/number_helper_test.rb
@@ -1,11 +1,12 @@
-require 'abstract_unit'
-require 'active_support/number_helper'
-require 'active_support/core_ext/string/output_safety'
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "active_support/number_helper"
+require "active_support/core_ext/string/output_safety"
 
 module ActiveSupport
   module NumberHelper
     class NumberHelperTest < ActiveSupport::TestCase
-
       class TestClassWithInstanceNumberHelpers
         include ActiveSupport::NumberHelper
       end
@@ -46,17 +47,17 @@ module ActiveSupport
         [@instance_with_helpers, TestClassWithClassNumberHelpers, ActiveSupport::NumberHelper].each do |number_helper|
           assert_equal("555-1234", number_helper.number_to_phone(5551234))
           assert_equal("800-555-1212", number_helper.number_to_phone(8005551212))
-          assert_equal("(800) 555-1212", number_helper.number_to_phone(8005551212, {:area_code => true}))
-          assert_equal("", number_helper.number_to_phone("", {:area_code => true}))
-          assert_equal("800 555 1212", number_helper.number_to_phone(8005551212, {:delimiter => " "}))
-          assert_equal("(800) 555-1212 x 123", number_helper.number_to_phone(8005551212, {:area_code => true, :extension => 123}))
-          assert_equal("800-555-1212", number_helper.number_to_phone(8005551212, :extension => "  "))
-          assert_equal("555.1212", number_helper.number_to_phone(5551212, :delimiter => '.'))
+          assert_equal("(800) 555-1212", number_helper.number_to_phone(8005551212, area_code: true))
+          assert_equal("", number_helper.number_to_phone("", area_code: true))
+          assert_equal("800 555 1212", number_helper.number_to_phone(8005551212, delimiter: " "))
+          assert_equal("(800) 555-1212 x 123", number_helper.number_to_phone(8005551212, area_code: true, extension: 123))
+          assert_equal("800-555-1212", number_helper.number_to_phone(8005551212, extension: "  "))
+          assert_equal("555.1212", number_helper.number_to_phone(5551212, delimiter: "."))
           assert_equal("800-555-1212", number_helper.number_to_phone("8005551212"))
-          assert_equal("+1-800-555-1212", number_helper.number_to_phone(8005551212, :country_code => 1))
-          assert_equal("+18005551212", number_helper.number_to_phone(8005551212, :country_code => 1, :delimiter => ''))
+          assert_equal("+1-800-555-1212", number_helper.number_to_phone(8005551212, country_code: 1))
+          assert_equal("+18005551212", number_helper.number_to_phone(8005551212, country_code: 1, delimiter: ""))
           assert_equal("22-555-1212", number_helper.number_to_phone(225551212))
-          assert_equal("+45-22-555-1212", number_helper.number_to_phone(225551212, :country_code => 45))
+          assert_equal("+45-22-555-1212", number_helper.number_to_phone(225551212, country_code: 45))
           assert_equal("(755) 6123-4567", number_helper.number_to_phone(75561234567, pattern: /(\d{3,4})(\d{4})(\d{4})/, area_code: true))
           assert_equal("133-1234-5678", number_helper.number_to_phone(13312345678, pattern: /(\d{3})(\d{4})(\d{4})/))
         end
@@ -67,28 +68,28 @@ module ActiveSupport
           assert_equal("$1,234,567,890.50", number_helper.number_to_currency(1234567890.50))
           assert_equal("$1,234,567,890.51", number_helper.number_to_currency(1234567890.506))
           assert_equal("-$1,234,567,890.50", number_helper.number_to_currency(-1234567890.50))
-          assert_equal("-$ 1,234,567,890.50", number_helper.number_to_currency(-1234567890.50, {:format => "%u %n"}))
-          assert_equal("($1,234,567,890.50)", number_helper.number_to_currency(-1234567890.50, {:negative_format => "(%u%n)"}))
-          assert_equal("$1,234,567,892", number_helper.number_to_currency(1234567891.50, {:precision => 0}))
-          assert_equal("$1,234,567,890.5", number_helper.number_to_currency(1234567890.50, {:precision => 1}))
-          assert_equal("&pound;1234567890,50", number_helper.number_to_currency(1234567890.50, {:unit => "&pound;", :separator => ",", :delimiter => ""}))
+          assert_equal("-$ 1,234,567,890.50", number_helper.number_to_currency(-1234567890.50, format: "%u %n"))
+          assert_equal("($1,234,567,890.50)", number_helper.number_to_currency(-1234567890.50, negative_format: "(%u%n)"))
+          assert_equal("$1,234,567,892", number_helper.number_to_currency(1234567891.50, precision: 0))
+          assert_equal("$1,234,567,890.5", number_helper.number_to_currency(1234567890.50, precision: 1))
+          assert_equal("&pound;1234567890,50", number_helper.number_to_currency(1234567890.50, unit: "&pound;", separator: ",", delimiter: ""))
           assert_equal("$1,234,567,890.50", number_helper.number_to_currency("1234567890.50"))
-          assert_equal("1,234,567,890.50 K&#269;", number_helper.number_to_currency("1234567890.50", {:unit => "K&#269;", :format => "%n %u"}))
-          assert_equal("1,234,567,890.50 - K&#269;", number_helper.number_to_currency("-1234567890.50", {:unit => "K&#269;", :format => "%n %u", :negative_format => "%n - %u"}))
-          assert_equal("0.00", number_helper.number_to_currency(+0.0, {:unit => "", :negative_format => "(%n)"}))
+          assert_equal("1,234,567,890.50 K&#269;", number_helper.number_to_currency("1234567890.50", unit: "K&#269;", format: "%n %u"))
+          assert_equal("1,234,567,890.50 - K&#269;", number_helper.number_to_currency("-1234567890.50", unit: "K&#269;", format: "%n %u", negative_format: "%n - %u"))
+          assert_equal("0.00", number_helper.number_to_currency(+0.0, unit: "", negative_format: "(%n)"))
         end
       end
 
       def test_number_to_percentage
         [@instance_with_helpers, TestClassWithClassNumberHelpers, ActiveSupport::NumberHelper].each do |number_helper|
           assert_equal("100.000%", number_helper.number_to_percentage(100))
-          assert_equal("100%", number_helper.number_to_percentage(100, {:precision => 0}))
-          assert_equal("302.06%", number_helper.number_to_percentage(302.0574, {:precision => 2}))
+          assert_equal("100%", number_helper.number_to_percentage(100, precision: 0))
+          assert_equal("302.06%", number_helper.number_to_percentage(302.0574, precision: 2))
           assert_equal("100.000%", number_helper.number_to_percentage("100"))
           assert_equal("1000.000%", number_helper.number_to_percentage("1000"))
-          assert_equal("123.4%", number_helper.number_to_percentage(123.400, :precision => 3, :strip_insignificant_zeros => true))
-          assert_equal("1.000,000%", number_helper.number_to_percentage(1000, :delimiter => '.', :separator => ','))
-          assert_equal("1000.000  %", number_helper.number_to_percentage(1000, :format => "%n  %"))
+          assert_equal("123.4%", number_helper.number_to_percentage(123.400, precision: 3, strip_insignificant_zeros: true))
+          assert_equal("1.000,000%", number_helper.number_to_percentage(1000, delimiter: ".", separator: ","))
+          assert_equal("1000.000  %", number_helper.number_to_percentage(1000, format: "%n  %"))
           assert_equal("98a%", number_helper.number_to_percentage("98a"))
           assert_equal("NaN%", number_helper.number_to_percentage(Float::NAN))
           assert_equal("Inf%", number_helper.number_to_percentage(Float::INFINITY))
@@ -122,9 +123,9 @@ module ActiveSupport
 
       def test_to_delimited_with_options_hash
         [@instance_with_helpers, TestClassWithClassNumberHelpers, ActiveSupport::NumberHelper].each do |number_helper|
-          assert_equal '12 345 678', number_helper.number_to_delimited(12345678, :delimiter => ' ')
-          assert_equal '12,345,678-05', number_helper.number_to_delimited(12345678.05, :separator => '-')
-          assert_equal '12.345.678,05', number_helper.number_to_delimited(12345678.05, :separator => ',', :delimiter => '.')
+          assert_equal "12 345 678", number_helper.number_to_delimited(12345678, delimiter: " ")
+          assert_equal "12,345,678-05", number_helper.number_to_delimited(12345678.05, separator: "-")
+          assert_equal "12.345.678,05", number_helper.number_to_delimited(12345678.05, separator: ",", delimiter: ".")
         end
       end
 
@@ -132,77 +133,77 @@ module ActiveSupport
         [@instance_with_helpers, TestClassWithClassNumberHelpers, ActiveSupport::NumberHelper].each do |number_helper|
           assert_equal("-111.235", number_helper.number_to_rounded(-111.2346))
           assert_equal("111.235", number_helper.number_to_rounded(111.2346))
-          assert_equal("31.83", number_helper.number_to_rounded(31.825, :precision => 2))
-          assert_equal("111.23", number_helper.number_to_rounded(111.2346, :precision => 2))
-          assert_equal("111.00", number_helper.number_to_rounded(111, :precision => 2))
+          assert_equal("31.83", number_helper.number_to_rounded(31.825, precision: 2))
+          assert_equal("111.23", number_helper.number_to_rounded(111.2346, precision: 2))
+          assert_equal("111.00", number_helper.number_to_rounded(111, precision: 2))
           assert_equal("111.235", number_helper.number_to_rounded("111.2346"))
-          assert_equal("31.83", number_helper.number_to_rounded("31.825", :precision => 2))
-          assert_equal("3268", number_helper.number_to_rounded((32.6751 * 100.00), :precision => 0))
-          assert_equal("112", number_helper.number_to_rounded(111.50, :precision => 0))
-          assert_equal("1234567892", number_helper.number_to_rounded(1234567891.50, :precision => 0))
-          assert_equal("0", number_helper.number_to_rounded(0, :precision => 0))
-          assert_equal("0.00100", number_helper.number_to_rounded(0.001, :precision => 5))
-          assert_equal("0.001", number_helper.number_to_rounded(0.00111, :precision => 3))
-          assert_equal("10.00", number_helper.number_to_rounded(9.995, :precision => 2))
-          assert_equal("11.00", number_helper.number_to_rounded(10.995, :precision => 2))
-          assert_equal("0.00", number_helper.number_to_rounded(-0.001, :precision => 2))
-
-          assert_equal("111.23460000000000000000", number_helper.number_to_rounded(111.2346, :precision => 20))
-          assert_equal("111.23460000000000000000", number_helper.number_to_rounded(Rational(1112346, 10000), :precision => 20))
-          assert_equal("111.23460000000000000000", number_helper.number_to_rounded('111.2346', :precision => 20))
-          assert_equal("111.23460000000000000000", number_helper.number_to_rounded(BigDecimal(111.2346, Float::DIG), :precision => 20))
-          assert_equal("111.2346" + "0"*96, number_helper.number_to_rounded('111.2346', :precision => 100))
-          assert_equal("111.2346", number_helper.number_to_rounded(Rational(1112346, 10000), :precision => 4))
-          assert_equal('0.00', number_helper.number_to_rounded(Rational(0, 1), :precision => 2))
+          assert_equal("31.83", number_helper.number_to_rounded("31.825", precision: 2))
+          assert_equal("3268", number_helper.number_to_rounded((32.6751 * 100.00), precision: 0))
+          assert_equal("112", number_helper.number_to_rounded(111.50, precision: 0))
+          assert_equal("1234567892", number_helper.number_to_rounded(1234567891.50, precision: 0))
+          assert_equal("0", number_helper.number_to_rounded(0, precision: 0))
+          assert_equal("0.00100", number_helper.number_to_rounded(0.001, precision: 5))
+          assert_equal("0.001", number_helper.number_to_rounded(0.00111, precision: 3))
+          assert_equal("10.00", number_helper.number_to_rounded(9.995, precision: 2))
+          assert_equal("11.00", number_helper.number_to_rounded(10.995, precision: 2))
+          assert_equal("0.00", number_helper.number_to_rounded(-0.001, precision: 2))
+
+          assert_equal("111.23460000000000000000", number_helper.number_to_rounded(111.2346, precision: 20))
+          assert_equal("111.23460000000000000000", number_helper.number_to_rounded(Rational(1112346, 10000), precision: 20))
+          assert_equal("111.23460000000000000000", number_helper.number_to_rounded("111.2346", precision: 20))
+          assert_equal("111.23460000000000000000", number_helper.number_to_rounded(BigDecimal(111.2346, Float::DIG), precision: 20))
+          assert_equal("111.2346" + "0" * 96, number_helper.number_to_rounded("111.2346", precision: 100))
+          assert_equal("111.2346", number_helper.number_to_rounded(Rational(1112346, 10000), precision: 4))
+          assert_equal("0.00", number_helper.number_to_rounded(Rational(0, 1), precision: 2))
         end
       end
 
       def test_to_rounded_with_custom_delimiter_and_separator
         [@instance_with_helpers, TestClassWithClassNumberHelpers, ActiveSupport::NumberHelper].each do |number_helper|
-          assert_equal '31,83',       number_helper.number_to_rounded(31.825, :precision => 2, :separator => ',')
-          assert_equal '1.231,83',    number_helper.number_to_rounded(1231.825, :precision => 2, :separator => ',', :delimiter => '.')
+          assert_equal "31,83",       number_helper.number_to_rounded(31.825, precision: 2, separator: ",")
+          assert_equal "1.231,83",    number_helper.number_to_rounded(1231.825, precision: 2, separator: ",", delimiter: ".")
         end
       end
 
       def test_to_rounded_with_significant_digits
         [@instance_with_helpers, TestClassWithClassNumberHelpers, ActiveSupport::NumberHelper].each do |number_helper|
-          assert_equal "124000", number_helper.number_to_rounded(123987, :precision => 3, :significant => true)
-          assert_equal "120000000", number_helper.number_to_rounded(123987876, :precision => 2, :significant => true )
-          assert_equal "40000", number_helper.number_to_rounded("43523", :precision => 1, :significant => true )
-          assert_equal "9775", number_helper.number_to_rounded(9775, :precision => 4, :significant => true )
-          assert_equal "5.4", number_helper.number_to_rounded(5.3923, :precision => 2, :significant => true )
-          assert_equal "5", number_helper.number_to_rounded(5.3923, :precision => 1, :significant => true )
-          assert_equal "1", number_helper.number_to_rounded(1.232, :precision => 1, :significant => true )
-          assert_equal "7", number_helper.number_to_rounded(7, :precision => 1, :significant => true )
-          assert_equal "1", number_helper.number_to_rounded(1, :precision => 1, :significant => true )
-          assert_equal "53", number_helper.number_to_rounded(52.7923, :precision => 2, :significant => true )
-          assert_equal "9775.00", number_helper.number_to_rounded(9775, :precision => 6, :significant => true )
-          assert_equal "5.392900", number_helper.number_to_rounded(5.3929, :precision => 7, :significant => true )
-          assert_equal "0.0", number_helper.number_to_rounded(0, :precision => 2, :significant => true )
-          assert_equal "0", number_helper.number_to_rounded(0, :precision => 1, :significant => true )
-          assert_equal "0.0001", number_helper.number_to_rounded(0.0001, :precision => 1, :significant => true )
-          assert_equal "0.000100", number_helper.number_to_rounded(0.0001, :precision => 3, :significant => true )
-          assert_equal "0.0001", number_helper.number_to_rounded(0.0001111, :precision => 1, :significant => true )
-          assert_equal "10.0", number_helper.number_to_rounded(9.995, :precision => 3, :significant => true)
-          assert_equal "9.99", number_helper.number_to_rounded(9.994, :precision => 3, :significant => true)
-          assert_equal "11.0", number_helper.number_to_rounded(10.995, :precision => 3, :significant => true)
-
-          assert_equal "9775.0000000000000000", number_helper.number_to_rounded(9775, :precision => 20, :significant => true )
-          assert_equal "9775.0000000000000000", number_helper.number_to_rounded(9775.0, :precision => 20, :significant => true )
-          assert_equal "9775.0000000000000000", number_helper.number_to_rounded(Rational(9775, 1), :precision => 20, :significant => true )
-          assert_equal "97.750000000000000000", number_helper.number_to_rounded(Rational(9775, 100), :precision => 20, :significant => true )
-          assert_equal "9775.0000000000000000", number_helper.number_to_rounded(BigDecimal(9775), :precision => 20, :significant => true )
-          assert_equal "9775.0000000000000000", number_helper.number_to_rounded("9775", :precision => 20, :significant => true )
-          assert_equal "9775." + "0"*96, number_helper.number_to_rounded("9775", :precision => 100, :significant => true )
-          assert_equal("97.7", number_helper.number_to_rounded(Rational(9772, 100), :precision => 3, :significant => true))
+          assert_equal "124000", number_helper.number_to_rounded(123987, precision: 3, significant: true)
+          assert_equal "120000000", number_helper.number_to_rounded(123987876, precision: 2, significant: true)
+          assert_equal "40000", number_helper.number_to_rounded("43523", precision: 1, significant: true)
+          assert_equal "9775", number_helper.number_to_rounded(9775, precision: 4, significant: true)
+          assert_equal "5.4", number_helper.number_to_rounded(5.3923, precision: 2, significant: true)
+          assert_equal "5", number_helper.number_to_rounded(5.3923, precision: 1, significant: true)
+          assert_equal "1", number_helper.number_to_rounded(1.232, precision: 1, significant: true)
+          assert_equal "7", number_helper.number_to_rounded(7, precision: 1, significant: true)
+          assert_equal "1", number_helper.number_to_rounded(1, precision: 1, significant: true)
+          assert_equal "53", number_helper.number_to_rounded(52.7923, precision: 2, significant: true)
+          assert_equal "9775.00", number_helper.number_to_rounded(9775, precision: 6, significant: true)
+          assert_equal "5.392900", number_helper.number_to_rounded(5.3929, precision: 7, significant: true)
+          assert_equal "0.0", number_helper.number_to_rounded(0, precision: 2, significant: true)
+          assert_equal "0", number_helper.number_to_rounded(0, precision: 1, significant: true)
+          assert_equal "0.0001", number_helper.number_to_rounded(0.0001, precision: 1, significant: true)
+          assert_equal "0.000100", number_helper.number_to_rounded(0.0001, precision: 3, significant: true)
+          assert_equal "0.0001", number_helper.number_to_rounded(0.0001111, precision: 1, significant: true)
+          assert_equal "10.0", number_helper.number_to_rounded(9.995, precision: 3, significant: true)
+          assert_equal "9.99", number_helper.number_to_rounded(9.994, precision: 3, significant: true)
+          assert_equal "11.0", number_helper.number_to_rounded(10.995, precision: 3, significant: true)
+
+          assert_equal "9775.0000000000000000", number_helper.number_to_rounded(9775, precision: 20, significant: true)
+          assert_equal "9775.0000000000000000", number_helper.number_to_rounded(9775.0, precision: 20, significant: true)
+          assert_equal "9775.0000000000000000", number_helper.number_to_rounded(Rational(9775, 1), precision: 20, significant: true)
+          assert_equal "97.750000000000000000", number_helper.number_to_rounded(Rational(9775, 100), precision: 20, significant: true)
+          assert_equal "9775.0000000000000000", number_helper.number_to_rounded(BigDecimal(9775), precision: 20, significant: true)
+          assert_equal "9775.0000000000000000", number_helper.number_to_rounded("9775", precision: 20, significant: true)
+          assert_equal "9775." + "0" * 96, number_helper.number_to_rounded("9775", precision: 100, significant: true)
+          assert_equal("97.7", number_helper.number_to_rounded(Rational(9772, 100), precision: 3, significant: true))
         end
       end
 
       def test_to_rounded_with_strip_insignificant_zeros
         [@instance_with_helpers, TestClassWithClassNumberHelpers, ActiveSupport::NumberHelper].each do |number_helper|
-          assert_equal "9775.43", number_helper.number_to_rounded(9775.43, :precision => 4, :strip_insignificant_zeros => true )
-          assert_equal "9775.2", number_helper.number_to_rounded(9775.2, :precision => 6, :significant => true, :strip_insignificant_zeros => true )
-          assert_equal "0", number_helper.number_to_rounded(0, :precision => 6, :significant => true, :strip_insignificant_zeros => true )
+          assert_equal "9775.43", number_helper.number_to_rounded(9775.43, precision: 4, strip_insignificant_zeros: true)
+          assert_equal "9775.2", number_helper.number_to_rounded(9775.2, precision: 6, significant: true, strip_insignificant_zeros: true)
+          assert_equal "0", number_helper.number_to_rounded(0, precision: 6, significant: true, strip_insignificant_zeros: true)
         end
       end
 
@@ -210,156 +211,145 @@ module ActiveSupport
         [@instance_with_helpers, TestClassWithClassNumberHelpers, ActiveSupport::NumberHelper].each do |number_helper|
           # Zero precision with significant is a mistake (would always return zero),
           # so we treat it as if significant was false (increases backwards compatibility for number_to_human_size)
-          assert_equal "124", number_helper.number_to_rounded(123.987, :precision => 0, :significant => true)
-          assert_equal "12", number_helper.number_to_rounded(12, :precision => 0, :significant => true )
-          assert_equal "12", number_helper.number_to_rounded("12.3", :precision => 0, :significant => true )
+          assert_equal "124", number_helper.number_to_rounded(123.987, precision: 0, significant: true)
+          assert_equal "12", number_helper.number_to_rounded(12, precision: 0, significant: true)
+          assert_equal "12", number_helper.number_to_rounded("12.3", precision: 0, significant: true)
         end
       end
 
       def test_number_number_to_human_size
         [@instance_with_helpers, TestClassWithClassNumberHelpers, ActiveSupport::NumberHelper].each do |number_helper|
-          assert_equal '0 Bytes',   number_helper.number_to_human_size(0)
-          assert_equal '1 Byte',    number_helper.number_to_human_size(1)
-          assert_equal '3 Bytes',   number_helper.number_to_human_size(3.14159265)
-          assert_equal '123 Bytes', number_helper.number_to_human_size(123.0)
-          assert_equal '123 Bytes', number_helper.number_to_human_size(123)
-          assert_equal '1.21 KB',    number_helper.number_to_human_size(1234)
-          assert_equal '12.1 KB',   number_helper.number_to_human_size(12345)
-          assert_equal '1.18 MB',    number_helper.number_to_human_size(1234567)
-          assert_equal '1.15 GB',    number_helper.number_to_human_size(1234567890)
-          assert_equal '1.12 TB',    number_helper.number_to_human_size(1234567890123)
-          assert_equal '1.1 PB',   number_helper.number_to_human_size(1234567890123456)
-          assert_equal '1.07 EB',   number_helper.number_to_human_size(1234567890123456789)
-          assert_equal '1030 EB',   number_helper.number_to_human_size(exabytes(1026))
-          assert_equal '444 KB',    number_helper.number_to_human_size(kilobytes(444))
-          assert_equal '1020 MB',   number_helper.number_to_human_size(megabytes(1023))
-          assert_equal '3 TB',      number_helper.number_to_human_size(terabytes(3))
-          assert_equal '1.2 MB',   number_helper.number_to_human_size(1234567, :precision => 2)
-          assert_equal '3 Bytes',   number_helper.number_to_human_size(3.14159265, :precision => 4)
-          assert_equal '123 Bytes', number_helper.number_to_human_size('123')
-          assert_equal '1 KB',   number_helper.number_to_human_size(kilobytes(1.0123), :precision => 2)
-          assert_equal '1.01 KB',   number_helper.number_to_human_size(kilobytes(1.0100), :precision => 4)
-          assert_equal '10 KB',   number_helper.number_to_human_size(kilobytes(10.000), :precision => 4)
-          assert_equal '1 Byte',   number_helper.number_to_human_size(1.1)
-          assert_equal '10 Bytes', number_helper.number_to_human_size(10)
-        end
-      end
-
-      def test_number_to_human_size_with_si_prefix
-        assert_deprecated do
-          [@instance_with_helpers, TestClassWithClassNumberHelpers, ActiveSupport::NumberHelper].each do |number_helper|
-            assert_equal '3 Bytes',    number_helper.number_to_human_size(3.14159265, :prefix => :si)
-            assert_equal '123 Bytes',  number_helper.number_to_human_size(123.0, :prefix => :si)
-            assert_equal '123 Bytes',  number_helper.number_to_human_size(123, :prefix => :si)
-            assert_equal '1.23 KB',    number_helper.number_to_human_size(1234, :prefix => :si)
-            assert_equal '12.3 KB',    number_helper.number_to_human_size(12345, :prefix => :si)
-            assert_equal '1.23 MB',    number_helper.number_to_human_size(1234567, :prefix => :si)
-            assert_equal '1.23 GB',    number_helper.number_to_human_size(1234567890, :prefix => :si)
-            assert_equal '1.23 TB',    number_helper.number_to_human_size(1234567890123, :prefix => :si)
-            assert_equal '1.23 PB',    number_helper.number_to_human_size(1234567890123456, :prefix => :si)
-            assert_equal '1.23 EB',    number_helper.number_to_human_size(1234567890123456789, :prefix => :si)
-          end
+          assert_equal "0 Bytes",   number_helper.number_to_human_size(0)
+          assert_equal "1 Byte",    number_helper.number_to_human_size(1)
+          assert_equal "3 Bytes",   number_helper.number_to_human_size(3.14159265)
+          assert_equal "123 Bytes", number_helper.number_to_human_size(123.0)
+          assert_equal "123 Bytes", number_helper.number_to_human_size(123)
+          assert_equal "1.21 KB",    number_helper.number_to_human_size(1234)
+          assert_equal "12.1 KB",   number_helper.number_to_human_size(12345)
+          assert_equal "1.18 MB",    number_helper.number_to_human_size(1234567)
+          assert_equal "1.15 GB",    number_helper.number_to_human_size(1234567890)
+          assert_equal "1.12 TB",    number_helper.number_to_human_size(1234567890123)
+          assert_equal "1.1 PB",   number_helper.number_to_human_size(1234567890123456)
+          assert_equal "1.07 EB",   number_helper.number_to_human_size(1234567890123456789)
+          assert_equal "1030 EB",   number_helper.number_to_human_size(exabytes(1026))
+          assert_equal "444 KB",    number_helper.number_to_human_size(kilobytes(444))
+          assert_equal "1020 MB",   number_helper.number_to_human_size(megabytes(1023))
+          assert_equal "3 TB",      number_helper.number_to_human_size(terabytes(3))
+          assert_equal "1.2 MB",   number_helper.number_to_human_size(1234567, precision: 2)
+          assert_equal "3 Bytes",   number_helper.number_to_human_size(3.14159265, precision: 4)
+          assert_equal "123 Bytes", number_helper.number_to_human_size("123")
+          assert_equal "1 KB",   number_helper.number_to_human_size(kilobytes(1.0123), precision: 2)
+          assert_equal "1.01 KB",   number_helper.number_to_human_size(kilobytes(1.0100), precision: 4)
+          assert_equal "10 KB",   number_helper.number_to_human_size(kilobytes(10.000), precision: 4)
+          assert_equal "1 Byte",   number_helper.number_to_human_size(1.1)
+          assert_equal "10 Bytes", number_helper.number_to_human_size(10)
         end
       end
 
       def test_number_to_human_size_with_options_hash
         [@instance_with_helpers, TestClassWithClassNumberHelpers, ActiveSupport::NumberHelper].each do |number_helper|
-          assert_equal '1.2 MB',   number_helper.number_to_human_size(1234567, :precision => 2)
-          assert_equal '3 Bytes',   number_helper.number_to_human_size(3.14159265, :precision => 4)
-          assert_equal '1 KB',   number_helper.number_to_human_size(kilobytes(1.0123), :precision => 2)
-          assert_equal '1.01 KB',   number_helper.number_to_human_size(kilobytes(1.0100), :precision => 4)
-          assert_equal '10 KB',     number_helper.number_to_human_size(kilobytes(10.000), :precision => 4)
-          assert_equal '1 TB', number_helper.number_to_human_size(1234567890123, :precision => 1)
-          assert_equal '500 MB', number_helper.number_to_human_size(524288000, :precision=>3)
-          assert_equal '10 MB', number_helper.number_to_human_size(9961472, :precision=>0)
-          assert_equal '40 KB', number_helper.number_to_human_size(41010, :precision => 1)
-          assert_equal '40 KB', number_helper.number_to_human_size(41100, :precision => 2)
-          assert_equal '1.0 KB',   number_helper.number_to_human_size(kilobytes(1.0123), :precision => 2, :strip_insignificant_zeros => false)
-          assert_equal '1.012 KB',   number_helper.number_to_human_size(kilobytes(1.0123), :precision => 3, :significant => false)
-          assert_equal '1 KB',   number_helper.number_to_human_size(kilobytes(1.0123), :precision => 0, :significant => true) #ignores significant it precision is 0
+          assert_equal "1.2 MB",   number_helper.number_to_human_size(1234567, precision: 2)
+          assert_equal "3 Bytes",   number_helper.number_to_human_size(3.14159265, precision: 4)
+          assert_equal "1 KB",   number_helper.number_to_human_size(kilobytes(1.0123), precision: 2)
+          assert_equal "1.01 KB",   number_helper.number_to_human_size(kilobytes(1.0100), precision: 4)
+          assert_equal "10 KB",     number_helper.number_to_human_size(kilobytes(10.000), precision: 4)
+          assert_equal "1 TB", number_helper.number_to_human_size(1234567890123, precision: 1)
+          assert_equal "500 MB", number_helper.number_to_human_size(524288000, precision: 3)
+          assert_equal "10 MB", number_helper.number_to_human_size(9961472, precision: 0)
+          assert_equal "40 KB", number_helper.number_to_human_size(41010, precision: 1)
+          assert_equal "40 KB", number_helper.number_to_human_size(41100, precision: 2)
+          assert_equal "1.0 KB",   number_helper.number_to_human_size(kilobytes(1.0123), precision: 2, strip_insignificant_zeros: false)
+          assert_equal "1.012 KB",   number_helper.number_to_human_size(kilobytes(1.0123), precision: 3, significant: false)
+          assert_equal "1 KB",   number_helper.number_to_human_size(kilobytes(1.0123), precision: 0, significant: true) # ignores significant it precision is 0
         end
       end
 
       def test_number_to_human_size_with_custom_delimiter_and_separator
         [@instance_with_helpers, TestClassWithClassNumberHelpers, ActiveSupport::NumberHelper].each do |number_helper|
-          assert_equal '1,01 KB',     number_helper.number_to_human_size(kilobytes(1.0123), :precision => 3, :separator => ',')
-          assert_equal '1,01 KB',     number_helper.number_to_human_size(kilobytes(1.0100), :precision => 4, :separator => ',')
-          assert_equal '1.000,1 TB',  number_helper.number_to_human_size(terabytes(1000.1), :precision => 5, :delimiter => '.', :separator => ',')
+          assert_equal "1,01 KB",     number_helper.number_to_human_size(kilobytes(1.0123), precision: 3, separator: ",")
+          assert_equal "1,01 KB",     number_helper.number_to_human_size(kilobytes(1.0100), precision: 4, separator: ",")
+          assert_equal "1.000,1 TB",  number_helper.number_to_human_size(terabytes(1000.1), precision: 5, delimiter: ".", separator: ",")
         end
       end
 
       def test_number_to_human
         [@instance_with_helpers, TestClassWithClassNumberHelpers, ActiveSupport::NumberHelper].each do |number_helper|
-          assert_equal '-123', number_helper.number_to_human(-123)
-          assert_equal '-0.5', number_helper.number_to_human(-0.5)
-          assert_equal '0',   number_helper.number_to_human(0)
-          assert_equal '0.5', number_helper.number_to_human(0.5)
-          assert_equal '123', number_helper.number_to_human(123)
-          assert_equal '1.23 Thousand', number_helper.number_to_human(1234)
-          assert_equal '12.3 Thousand', number_helper.number_to_human(12345)
-          assert_equal '1.23 Million', number_helper.number_to_human(1234567)
-          assert_equal '1.23 Billion', number_helper.number_to_human(1234567890)
-          assert_equal '1.23 Trillion', number_helper.number_to_human(1234567890123)
-          assert_equal '1.23 Quadrillion', number_helper.number_to_human(1234567890123456)
-          assert_equal '1230 Quadrillion', number_helper.number_to_human(1234567890123456789)
-          assert_equal '490 Thousand', number_helper.number_to_human(489939, :precision => 2)
-          assert_equal '489.9 Thousand', number_helper.number_to_human(489939, :precision => 4)
-          assert_equal '489 Thousand', number_helper.number_to_human(489000, :precision => 4)
-          assert_equal '489.0 Thousand', number_helper.number_to_human(489000, :precision => 4, :strip_insignificant_zeros => false)
-          assert_equal '1.2346 Million', number_helper.number_to_human(1234567, :precision => 4, :significant => false)
-          assert_equal '1,2 Million', number_helper.number_to_human(1234567, :precision => 1, :significant => false, :separator => ',')
-          assert_equal '1 Million', number_helper.number_to_human(1234567, :precision => 0, :significant => true, :separator => ',') #significant forced to false
-          assert_equal '1 Million', number_helper.number_to_human(999999)
-          assert_equal '1 Billion', number_helper.number_to_human(999999999)
+          assert_equal "-123", number_helper.number_to_human(-123)
+          assert_equal "-0.5", number_helper.number_to_human(-0.5)
+          assert_equal "0",   number_helper.number_to_human(0)
+          assert_equal "0.5", number_helper.number_to_human(0.5)
+          assert_equal "123", number_helper.number_to_human(123)
+          assert_equal "1.23 Thousand", number_helper.number_to_human(1234)
+          assert_equal "12.3 Thousand", number_helper.number_to_human(12345)
+          assert_equal "1.23 Million", number_helper.number_to_human(1234567)
+          assert_equal "1.23 Billion", number_helper.number_to_human(1234567890)
+          assert_equal "1.23 Trillion", number_helper.number_to_human(1234567890123)
+          assert_equal "1.23 Quadrillion", number_helper.number_to_human(1234567890123456)
+          assert_equal "1230 Quadrillion", number_helper.number_to_human(1234567890123456789)
+          assert_equal "490 Thousand", number_helper.number_to_human(489939, precision: 2)
+          assert_equal "489.9 Thousand", number_helper.number_to_human(489939, precision: 4)
+          assert_equal "489 Thousand", number_helper.number_to_human(489000, precision: 4)
+          assert_equal "489.0 Thousand", number_helper.number_to_human(489000, precision: 4, strip_insignificant_zeros: false)
+          assert_equal "1.2346 Million", number_helper.number_to_human(1234567, precision: 4, significant: false)
+          assert_equal "1,2 Million", number_helper.number_to_human(1234567, precision: 1, significant: false, separator: ",")
+          assert_equal "1 Million", number_helper.number_to_human(1234567, precision: 0, significant: true, separator: ",") # significant forced to false
+          assert_equal "1 Million", number_helper.number_to_human(999999)
+          assert_equal "1 Billion", number_helper.number_to_human(999999999)
         end
       end
 
       def test_number_to_human_with_custom_units
         [@instance_with_helpers, TestClassWithClassNumberHelpers, ActiveSupport::NumberHelper].each do |number_helper|
-          #Only integers
-          volume = {:unit => "ml", :thousand => "lt", :million => "m3"}
-          assert_equal '123 lt', number_helper.number_to_human(123456, :units => volume)
-          assert_equal '12 ml', number_helper.number_to_human(12, :units => volume)
-          assert_equal '1.23 m3', number_helper.number_to_human(1234567, :units => volume)
-
-          #Including fractionals
-          distance = {:mili => "mm", :centi => "cm", :deci => "dm", :unit => "m", :ten => "dam", :hundred => "hm", :thousand => "km"}
-          assert_equal '1.23 mm', number_helper.number_to_human(0.00123, :units => distance)
-          assert_equal '1.23 cm', number_helper.number_to_human(0.0123, :units => distance)
-          assert_equal '1.23 dm', number_helper.number_to_human(0.123, :units => distance)
-          assert_equal '1.23 m', number_helper.number_to_human(1.23, :units => distance)
-          assert_equal '1.23 dam', number_helper.number_to_human(12.3, :units => distance)
-          assert_equal '1.23 hm', number_helper.number_to_human(123, :units => distance)
-          assert_equal '1.23 km', number_helper.number_to_human(1230, :units => distance)
-          assert_equal '1.23 km', number_helper.number_to_human(1230, :units => distance)
-          assert_equal '1.23 km', number_helper.number_to_human(1230, :units => distance)
-          assert_equal '12.3 km', number_helper.number_to_human(12300, :units => distance)
-
-          #The quantifiers don't need to be a continuous sequence
-          gangster = {:hundred => "hundred bucks", :million => "thousand quids"}
-          assert_equal '1 hundred bucks', number_helper.number_to_human(100, :units => gangster)
-          assert_equal '25 hundred bucks', number_helper.number_to_human(2500, :units => gangster)
-          assert_equal '25 thousand quids', number_helper.number_to_human(25000000, :units => gangster)
-          assert_equal '12300 thousand quids', number_helper.number_to_human(12345000000, :units => gangster)
-
-          #Spaces are stripped from the resulting string
-          assert_equal '4', number_helper.number_to_human(4, :units => {:unit => "", :ten => 'tens '})
-          assert_equal '4.5  tens', number_helper.number_to_human(45, :units => {:unit => "", :ten => ' tens   '})
+          # Only integers
+          volume = { unit: "ml", thousand: "lt", million: "m3" }
+          assert_equal "123 lt", number_helper.number_to_human(123456, units: volume)
+          assert_equal "12 ml", number_helper.number_to_human(12, units: volume)
+          assert_equal "1.23 m3", number_helper.number_to_human(1234567, units: volume)
+
+          # Including fractionals
+          distance = { mili: "mm", centi: "cm", deci: "dm", unit: "m", ten: "dam", hundred: "hm", thousand: "km" }
+          assert_equal "1.23 mm", number_helper.number_to_human(0.00123, units: distance)
+          assert_equal "1.23 cm", number_helper.number_to_human(0.0123, units: distance)
+          assert_equal "1.23 dm", number_helper.number_to_human(0.123, units: distance)
+          assert_equal "1.23 m", number_helper.number_to_human(1.23, units: distance)
+          assert_equal "1.23 dam", number_helper.number_to_human(12.3, units: distance)
+          assert_equal "1.23 hm", number_helper.number_to_human(123, units: distance)
+          assert_equal "1.23 km", number_helper.number_to_human(1230, units: distance)
+          assert_equal "1.23 km", number_helper.number_to_human(1230, units: distance)
+          assert_equal "1.23 km", number_helper.number_to_human(1230, units: distance)
+          assert_equal "12.3 km", number_helper.number_to_human(12300, units: distance)
+
+          # The quantifiers don't need to be a continuous sequence
+          gangster = { hundred: "hundred bucks", million: "thousand quids" }
+          assert_equal "1 hundred bucks", number_helper.number_to_human(100, units: gangster)
+          assert_equal "25 hundred bucks", number_helper.number_to_human(2500, units: gangster)
+          assert_equal "1000 hundred bucks", number_helper.number_to_human(100_000, units: gangster)
+          assert_equal "1 thousand quids", number_helper.number_to_human(999_999, units: gangster)
+          assert_equal "1 thousand quids", number_helper.number_to_human(1_000_000, units: gangster)
+          assert_equal "25 thousand quids", number_helper.number_to_human(25000000, units: gangster)
+          assert_equal "12300 thousand quids", number_helper.number_to_human(12345000000, units: gangster)
+
+          # Spaces are stripped from the resulting string
+          assert_equal "4", number_helper.number_to_human(4, units: { unit: "", ten: "tens " })
+          assert_equal "4.5  tens", number_helper.number_to_human(45, units: { unit: "", ten: " tens   " })
+
+          # Uses only the provided units and does not try to use larger ones
+          assert_equal "1000 kilometers", number_helper.number_to_human(1_000_000, units: { unit: "meter", thousand: "kilometers" })
         end
       end
 
       def test_number_to_human_with_custom_units_that_are_missing_the_needed_key
         [@instance_with_helpers, TestClassWithClassNumberHelpers, ActiveSupport::NumberHelper].each do |number_helper|
-          assert_equal '123', number_helper.number_to_human(123, units: { thousand: 'k'})
-          assert_equal '123', number_helper.number_to_human(123, units: {})
+          assert_equal "123", number_helper.number_to_human(123, units: { thousand: "k" })
+          assert_equal "123", number_helper.number_to_human(123, units: {})
         end
       end
 
       def test_number_to_human_with_custom_format
         [@instance_with_helpers, TestClassWithClassNumberHelpers, ActiveSupport::NumberHelper].each do |number_helper|
-          assert_equal '123 times Thousand', number_helper.number_to_human(123456, :format => "%n times %u")
-          volume = {:unit => "ml", :thousand => "lt", :million => "m3"}
-          assert_equal '123.lt', number_helper.number_to_human(123456, :units => volume, :format => "%n.%u")
+          assert_equal "123 times Thousand", number_helper.number_to_human(123456, format: "%n times %u")
+          volume = { unit: "ml", thousand: "lt", million: "m3" }
+          assert_equal "123.lt", number_helper.number_to_human(123456, units: volume, format: "%n.%u")
         end
       end
 
@@ -377,34 +367,34 @@ module ActiveSupport
 
       def test_number_helpers_do_not_mutate_options_hash
         [@instance_with_helpers, TestClassWithClassNumberHelpers, ActiveSupport::NumberHelper].each do |number_helper|
-          options = { 'raise' => true }
+          options = { "raise" => true }
 
           number_helper.number_to_phone(1, options)
-          assert_equal({ 'raise' => true }, options)
+          assert_equal({ "raise" => true }, options)
 
           number_helper.number_to_currency(1, options)
-          assert_equal({ 'raise' => true }, options)
+          assert_equal({ "raise" => true }, options)
 
           number_helper.number_to_percentage(1, options)
-          assert_equal({ 'raise' => true }, options)
+          assert_equal({ "raise" => true }, options)
 
           number_helper.number_to_delimited(1, options)
-          assert_equal({ 'raise' => true }, options)
+          assert_equal({ "raise" => true }, options)
 
           number_helper.number_to_rounded(1, options)
-          assert_equal({ 'raise' => true }, options)
+          assert_equal({ "raise" => true }, options)
 
           number_helper.number_to_human_size(1, options)
-          assert_equal({ 'raise' => true }, options)
+          assert_equal({ "raise" => true }, options)
 
           number_helper.number_to_human(1, options)
-          assert_equal({ 'raise' => true }, options)
+          assert_equal({ "raise" => true }, options)
         end
       end
 
       def test_number_helpers_should_return_non_numeric_param_unchanged
         [@instance_with_helpers, TestClassWithClassNumberHelpers, ActiveSupport::NumberHelper].each do |number_helper|
-          assert_equal("+1-x x 123", number_helper.number_to_phone("x", :country_code => 1, :extension => 123))
+          assert_equal("+1-x x 123", number_helper.number_to_phone("x", country_code: 1, extension: 123))
           assert_equal("x", number_helper.number_to_phone("x"))
           assert_equal("$x.", number_helper.number_to_currency("x."))
           assert_equal("$x", number_helper.number_to_currency("x"))
@@ -412,11 +402,10 @@ module ActiveSupport
           assert_equal("x", number_helper.number_to_delimited("x"))
           assert_equal("x.", number_helper.number_to_rounded("x."))
           assert_equal("x", number_helper.number_to_rounded("x"))
-          assert_equal "x", number_helper.number_to_human_size('x')
-          assert_equal "x", number_helper.number_to_human('x')
+          assert_equal "x", number_helper.number_to_human_size("x")
+          assert_equal "x", number_helper.number_to_human("x")
         end
       end
-
     end
   end
 end
diff --git a/activesupport/test/option_merger_test.rb b/activesupport/test/option_merger_test.rb
index 4c0364e68b..935e2aee63 100644
--- a/activesupport/test/option_merger_test.rb
+++ b/activesupport/test/option_merger_test.rb
@@ -1,13 +1,15 @@
-require 'abstract_unit'
-require 'active_support/core_ext/object/with_options'
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "active_support/core_ext/object/with_options"
 
 class OptionMergerTest < ActiveSupport::TestCase
   def setup
-    @options = {:hello => 'world'}
+    @options = { hello: "world" }
   end
 
   def test_method_with_options_merges_options_when_options_are_present
-    local_options = {:cool => true}
+    local_options = { cool: true }
 
     with_options(@options) do |o|
       assert_equal local_options, method_with_options(local_options)
@@ -24,7 +26,7 @@ class OptionMergerTest < ActiveSupport::TestCase
   end
 
   def test_method_with_options_allows_to_overwrite_options
-    local_options = {:hello => 'moon'}
+    local_options = { hello: "moon" }
     assert_equal @options.keys, local_options.keys
 
     with_options(@options) do |o|
@@ -40,34 +42,34 @@ class OptionMergerTest < ActiveSupport::TestCase
   end
 
   def test_nested_method_with_options_containing_hashes_merge
-    with_options :conditions => { :method => :get } do |outer|
-      outer.with_options :conditions => { :domain => "www" } do |inner|
-        expected = { :conditions => { :method => :get, :domain => "www" } }
+    with_options conditions: { method: :get } do |outer|
+      outer.with_options conditions: { domain: "www" } do |inner|
+        expected = { conditions: { method: :get, domain: "www" } }
         assert_equal expected, inner.method_with_options
       end
     end
   end
 
   def test_nested_method_with_options_containing_hashes_overwrite
-    with_options :conditions => { :method => :get, :domain => "www" } do |outer|
-      outer.with_options :conditions => { :method => :post } do |inner|
-        expected = { :conditions => { :method => :post, :domain => "www" } }
+    with_options conditions: { method: :get, domain: "www" } do |outer|
+      outer.with_options conditions: { method: :post } do |inner|
+        expected = { conditions: { method: :post, domain: "www" } }
         assert_equal expected, inner.method_with_options
       end
     end
   end
 
   def test_nested_method_with_options_containing_hashes_going_deep
-    with_options :html => { :class => "foo", :style => { :margin => 0, :display => "block" } } do |outer|
-      outer.with_options :html => { :title => "bar", :style => { :margin => "1em", :color => "#fff" } } do |inner|
-        expected = { :html => { :class => "foo", :title => "bar", :style => { :margin => "1em", :display => "block", :color => "#fff" } } }
+    with_options html: { class: "foo", style: { margin: 0, display: "block" } } do |outer|
+      outer.with_options html: { title: "bar", style: { margin: "1em", color: "#fff" } } do |inner|
+        expected = { html: { class: "foo", title: "bar", style: { margin: "1em", display: "block", color: "#fff" } } }
         assert_equal expected, inner.method_with_options
       end
     end
   end
 
   def test_nested_method_with_options_using_lambda
-    local_lambda = lambda { { :lambda => true } }
+    local_lambda = lambda { { lambda: true } }
     with_options(@options) do |o|
       assert_equal @options.merge(local_lambda.call),
         o.method_with_options(local_lambda).call
@@ -76,7 +78,7 @@ class OptionMergerTest < ActiveSupport::TestCase
 
   # Needed when counting objects with the ObjectSpace
   def test_option_merger_class_method
-    assert_equal ActiveSupport::OptionMerger, ActiveSupport::OptionMerger.new('', '').class
+    assert_equal ActiveSupport::OptionMerger, ActiveSupport::OptionMerger.new("", "").class
   end
 
   def test_option_merger_implicit_receiver
diff --git a/activesupport/test/ordered_hash_test.rb b/activesupport/test/ordered_hash_test.rb
index 460a61613e..c70d3b4c37 100644
--- a/activesupport/test/ordered_hash_test.rb
+++ b/activesupport/test/ordered_hash_test.rb
@@ -1,8 +1,10 @@
-require 'abstract_unit'
-require 'active_support/json'
-require 'active_support/core_ext/object/json'
-require 'active_support/core_ext/hash/indifferent_access'
-require 'active_support/core_ext/array/extract_options'
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "active_support/json"
+require "active_support/core_ext/object/json"
+require "active_support/core_ext/hash/indifferent_access"
+require "active_support/core_ext/array/extract_options"
 
 class OrderedHashTest < ActiveSupport::TestCase
   def setup
@@ -27,7 +29,7 @@ class OrderedHashTest < ActiveSupport::TestCase
   end
 
   def test_assignment
-    key, value = 'purple', '5422a8'
+    key, value = "purple", "5422a8"
 
     @ordered_hash[key] = value
     assert_equal @keys.length + 1, @ordered_hash.length
@@ -37,8 +39,8 @@ class OrderedHashTest < ActiveSupport::TestCase
   end
 
   def test_delete
-    key, value = 'white', 'ffffff'
-    bad_key = 'black'
+    key, value = "white", "ffffff"
+    bad_key = "black"
 
     @ordered_hash[key] = value
     assert_equal @keys.length + 1, @ordered_hash.length
@@ -60,22 +62,22 @@ class OrderedHashTest < ActiveSupport::TestCase
   end
 
   def test_has_key
-    assert_equal true, @ordered_hash.has_key?('blue')
-    assert_equal true, @ordered_hash.key?('blue')
-    assert_equal true, @ordered_hash.include?('blue')
-    assert_equal true, @ordered_hash.member?('blue')
+    assert_equal true, @ordered_hash.has_key?("blue")
+    assert_equal true, @ordered_hash.key?("blue")
+    assert_equal true, @ordered_hash.include?("blue")
+    assert_equal true, @ordered_hash.member?("blue")
 
-    assert_equal false, @ordered_hash.has_key?('indigo')
-    assert_equal false, @ordered_hash.key?('indigo')
-    assert_equal false, @ordered_hash.include?('indigo')
-    assert_equal false, @ordered_hash.member?('indigo')
+    assert_equal false, @ordered_hash.has_key?("indigo")
+    assert_equal false, @ordered_hash.key?("indigo")
+    assert_equal false, @ordered_hash.include?("indigo")
+    assert_equal false, @ordered_hash.member?("indigo")
   end
 
   def test_has_value
-    assert_equal true, @ordered_hash.has_value?('000099')
-    assert_equal true, @ordered_hash.value?('000099')
-    assert_equal false, @ordered_hash.has_value?('ABCABC')
-    assert_equal false, @ordered_hash.value?('ABCABC')
+    assert_equal true, @ordered_hash.has_value?("000099")
+    assert_equal true, @ordered_hash.value?("000099")
+    assert_equal false, @ordered_hash.has_value?("ABCABC")
+    assert_equal false, @ordered_hash.value?("ABCABC")
   end
 
   def test_each_key
@@ -94,13 +96,13 @@ class OrderedHashTest < ActiveSupport::TestCase
 
   def test_each
     values = []
-    assert_equal @ordered_hash, @ordered_hash.each {|key, value| values << value}
+    assert_equal @ordered_hash, @ordered_hash.each { |key, value| values << value }
     assert_equal @values, values
     assert_kind_of Enumerator, @ordered_hash.each
   end
 
   def test_each_with_index
-    @ordered_hash.each_with_index { |pair, index| assert_equal [@keys[index], @values[index]], pair}
+    @ordered_hash.each_with_index { |pair, index| assert_equal [@keys[index], @values[index]], pair }
   end
 
   def test_each_pair
@@ -127,24 +129,24 @@ class OrderedHashTest < ActiveSupport::TestCase
 
   def test_delete_if
     copy = @ordered_hash.dup
-    copy.delete('pink')
-    assert_equal copy, @ordered_hash.delete_if { |k, _| k == 'pink' }
-    assert !@ordered_hash.keys.include?('pink')
+    copy.delete("pink")
+    assert_equal copy, @ordered_hash.delete_if { |k, _| k == "pink" }
+    assert_not_includes @ordered_hash.keys, "pink"
   end
 
   def test_reject!
-    (copy = @ordered_hash.dup).delete('pink')
-    @ordered_hash.reject! { |k, _| k == 'pink' }
+    (copy = @ordered_hash.dup).delete("pink")
+    @ordered_hash.reject! { |k, _| k == "pink" }
     assert_equal copy, @ordered_hash
-    assert !@ordered_hash.keys.include?('pink')
+    assert_not_includes @ordered_hash.keys, "pink"
   end
 
   def test_reject
     copy = @ordered_hash.dup
-    new_ordered_hash = @ordered_hash.reject { |k, _| k == 'pink' }
+    new_ordered_hash = @ordered_hash.reject { |k, _| k == "pink" }
     assert_equal copy, @ordered_hash
-    assert !new_ordered_hash.keys.include?('pink')
-    assert @ordered_hash.keys.include?('pink')
+    assert_not_includes new_ordered_hash.keys, "pink"
+    assert_includes @ordered_hash.keys, "pink"
     assert_instance_of ActiveSupport::OrderedHash, new_ordered_hash
   end
 
@@ -154,19 +156,19 @@ class OrderedHashTest < ActiveSupport::TestCase
   end
 
   def test_merge
-    other_hash =  ActiveSupport::OrderedHash.new
-    other_hash['purple'] = '800080'
-    other_hash['violet'] = 'ee82ee'
+    other_hash = ActiveSupport::OrderedHash.new
+    other_hash["purple"] = "800080"
+    other_hash["violet"] = "ee82ee"
     merged = @ordered_hash.merge other_hash
     assert_equal merged.length, @ordered_hash.length + other_hash.length
-    assert_equal @keys + ['purple', 'violet'], merged.keys
+    assert_equal @keys + ["purple", "violet"], merged.keys
   end
 
   def test_merge_with_block
     hash = ActiveSupport::OrderedHash.new
     hash[:a] = 0
     hash[:b] = 0
-    merged = hash.merge(:b => 2, :c => 7) do |key, old_value, new_value|
+    merged = hash.merge(b: 2, c: 7) do |key, old_value, new_value|
       new_value + 1
     end
 
@@ -179,7 +181,7 @@ class OrderedHashTest < ActiveSupport::TestCase
     hash = ActiveSupport::OrderedHash.new
     hash[:a] = 0
     hash[:b] = 0
-    hash.merge!(:a => 1, :c => 7) do |key, old_value, new_value|
+    hash.merge!(a: 1, c: 7) do |key, old_value, new_value|
       new_value + 3
     end
 
@@ -191,7 +193,7 @@ class OrderedHashTest < ActiveSupport::TestCase
   def test_shift
     pair = @ordered_hash.shift
     assert_equal [@keys.first, @values.first], pair
-    assert !@ordered_hash.keys.include?(pair.first)
+    assert_not_includes @ordered_hash.keys, pair.first
   end
 
   def test_keys
@@ -201,7 +203,7 @@ class OrderedHashTest < ActiveSupport::TestCase
   end
 
   def test_inspect
-    assert @ordered_hash.inspect.include?(@hash.inspect)
+    assert_includes @ordered_hash.inspect, @hash.inspect
   end
 
   def test_json
@@ -211,7 +213,7 @@ class OrderedHashTest < ActiveSupport::TestCase
   end
 
   def test_alternate_initialization_with_splat
-    alternate = ActiveSupport::OrderedHash[1,2,3,4]
+    alternate = ActiveSupport::OrderedHash[1, 2, 3, 4]
     assert_kind_of ActiveSupport::OrderedHash, alternate
     assert_equal [1, 3], alternate.keys
   end
@@ -220,29 +222,29 @@ class OrderedHashTest < ActiveSupport::TestCase
     alternate = ActiveSupport::OrderedHash[ [
       [1, 2],
       [3, 4],
-      [ 'missing value' ]
+      [ "missing value" ]
     ]]
 
     assert_kind_of ActiveSupport::OrderedHash, alternate
-    assert_equal [1, 3, 'missing value'], alternate.keys
+    assert_equal [1, 3, "missing value"], alternate.keys
     assert_equal [2, 4, nil ], alternate.values
   end
 
   def test_alternate_initialization_raises_exception_on_odd_length_args
     assert_raises ArgumentError do
-      ActiveSupport::OrderedHash[1,2,3,4,5]
+      ActiveSupport::OrderedHash[1, 2, 3, 4, 5]
     end
   end
 
   def test_replace_updates_keys
-    @other_ordered_hash = ActiveSupport::OrderedHash[:black, '000000', :white, '000000']
+    @other_ordered_hash = ActiveSupport::OrderedHash[:black, "000000", :white, "000000"]
     original = @ordered_hash.replace(@other_ordered_hash)
     assert_same original, @ordered_hash
     assert_equal @other_ordered_hash.keys, @ordered_hash.keys
   end
 
   def test_nested_under_indifferent_access
-    flash = {:a => ActiveSupport::OrderedHash[:b, 1, :c, 2]}.with_indifferent_access
+    flash = { a: ActiveSupport::OrderedHash[:b, 1, :c, 2] }.with_indifferent_access
     assert_kind_of ActiveSupport::OrderedHash, flash[:a]
   end
 
@@ -295,17 +297,17 @@ class OrderedHashTest < ActiveSupport::TestCase
 
   def test_psych_serialize_tag
     yaml = Psych.dump(@ordered_hash)
-    assert_match '!omap', yaml
+    assert_match "!omap", yaml
   end
 
   def test_has_yaml_tag
     @ordered_hash[:array] = %w(a b c)
-    assert_match '!omap', YAML.dump(@ordered_hash)
+    assert_match "!omap", YAML.dump(@ordered_hash)
   end
 
   def test_update_sets_keys
     @updated_ordered_hash = ActiveSupport::OrderedHash.new
-    @updated_ordered_hash.update(:name => "Bob")
+    @updated_ordered_hash.update(name: "Bob")
     assert_equal [:name],  @updated_ordered_hash.keys
   end
 
diff --git a/activesupport/test/ordered_options_test.rb b/activesupport/test/ordered_options_test.rb
index 18767a3536..2c67bb02ac 100644
--- a/activesupport/test/ordered_options_test.rb
+++ b/activesupport/test/ordered_options_test.rb
@@ -1,5 +1,7 @@
-require 'abstract_unit'
-require 'active_support/ordered_options'
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "active_support/ordered_options"
 
 class OrderedOptionsTest < ActiveSupport::TestCase
   def test_usage
@@ -100,4 +102,17 @@ class OrderedOptionsTest < ActiveSupport::TestCase
     end
     assert_raises(KeyError) { a.non_existing_key! }
   end
+
+  def test_inheritable_options_with_bang
+    a = ActiveSupport::InheritableOptions.new(foo: :bar)
+
+    assert_nothing_raised { a.foo! }
+    assert_equal a.foo, a.foo!
+
+    assert_raises(KeyError) do
+      a.foo = nil
+      a.foo!
+    end
+    assert_raises(KeyError) { a.non_existing_key! }
+  end
 end
diff --git a/activesupport/test/reloader_test.rb b/activesupport/test/reloader_test.rb
index 958cb49993..3e4229eaf7 100644
--- a/activesupport/test/reloader_test.rb
+++ b/activesupport/test/reloader_test.rb
@@ -1,13 +1,18 @@
-require 'abstract_unit'
+# frozen_string_literal: true
+
+require "abstract_unit"
 
 class ReloaderTest < ActiveSupport::TestCase
   def test_prepare_callback
-    prepared = false
+    prepared = completed = false
     reloader.to_prepare { prepared = true }
+    reloader.to_complete { completed = true }
 
     assert !prepared
+    assert !completed
     reloader.prepare!
     assert prepared
+    assert !completed
 
     prepared = false
     reloader.wrap do
@@ -17,17 +22,26 @@ class ReloaderTest < ActiveSupport::TestCase
     assert !prepared
   end
 
+  def test_prepend_prepare_callback
+    i = 10
+    reloader.to_prepare { i += 1 }
+    reloader.to_prepare(prepend: true) { i = 0 }
+
+    reloader.prepare!
+    assert_equal 1, i
+  end
+
   def test_only_run_when_check_passes
     r = new_reloader { true }
     invoked = false
     r.to_run { invoked = true }
-    r.wrap { }
+    r.wrap {}
     assert invoked
 
     r = new_reloader { false }
     invoked = false
     r.to_run { invoked = true }
-    r.wrap { }
+    r.wrap {}
     assert !invoked
   end
 
@@ -39,7 +53,7 @@ class ReloaderTest < ActiveSupport::TestCase
     reloader.executor.to_run { called << :executor_run }
     reloader.executor.to_complete { called << :executor_complete }
 
-    reloader.wrap { }
+    reloader.wrap {}
     assert_equal [:executor_run, :reloader_run, :prepare, :reloader_complete, :executor_complete], called
 
     called = []
@@ -49,7 +63,7 @@ class ReloaderTest < ActiveSupport::TestCase
     reloader.check = lambda { false }
 
     called = []
-    reloader.wrap { }
+    reloader.wrap {}
     assert_equal [:executor_run, :executor_complete], called
 
     called = []
diff --git a/activesupport/test/rescuable_test.rb b/activesupport/test/rescuable_test.rb
index e42e6d2973..b1b8a25c5b 100644
--- a/activesupport/test/rescuable_test.rb
+++ b/activesupport/test/rescuable_test.rb
@@ -1,4 +1,6 @@
-require 'abstract_unit'
+# frozen_string_literal: true
+
+require "abstract_unit"
 
 class WraithAttack < StandardError
 end
@@ -24,12 +26,12 @@ class Stargate
 
   include ActiveSupport::Rescuable
 
-  rescue_from WraithAttack, :with => :sos_first
+  rescue_from WraithAttack, with: :sos_first
 
-  rescue_from WraithAttack, :with => :sos
+  rescue_from WraithAttack, with: :sos
 
-  rescue_from 'NuclearExplosion' do
-    @result = 'alldead'
+  rescue_from "NuclearExplosion" do
+    @result = "alldead"
   end
 
   rescue_from MadRonon do |e|
@@ -37,13 +39,15 @@ class Stargate
   end
 
   rescue_from WeirdError do
-    @result = 'weird'
+    @result = "weird"
   end
 
   def dispatch(method)
     send(method)
   rescue Exception => e
-    rescue_with_handler(e)
+    unless rescue_with_handler(e)
+      @result = "unhandled"
+    end
   end
 
   def attack
@@ -58,12 +62,32 @@ class Stargate
     raise MadRonon.new("dex")
   end
 
+  def crash
+    raise "unhandled RuntimeError"
+  end
+
+  def looped_crash
+    ex1 = StandardError.new("error 1")
+    ex2 = StandardError.new("error 2")
+    begin
+      begin
+        raise ex1
+      rescue
+        # sets the cause on ex2 to be ex1
+        raise ex2
+      end
+    rescue
+      # sets the cause on ex1 to be ex2
+      raise ex1
+    end
+  end
+
   def fall_back_to_cause
     # This exception is the cause and has a handler.
     ronanize
   rescue
     # This is the exception we'll handle that doesn't have a cause.
-    raise 'unhandled RuntimeError with a handleable cause'
+    raise "unhandled RuntimeError with a handleable cause"
   end
 
   def weird
@@ -77,11 +101,11 @@ class Stargate
   end
 
   def sos
-    @result = 'killed'
+    @result = "killed"
   end
 
   def sos_first
-    @result = 'sos_first'
+    @result = "sos_first"
   end
 end
 
@@ -90,14 +114,13 @@ class CoolStargate < Stargate
 
   include ActiveSupport::Rescuable
 
-  rescue_from CoolError, :with => :sos_cool_error
+  rescue_from CoolError, with: :sos_cool_error
 
   def sos_cool_error
-    @result = 'sos_cool_error'
+    @result = "sos_cool_error"
   end
 end
 
-
 class RescuableTest < ActiveSupport::TestCase
   def setup
     @stargate = Stargate.new
@@ -106,22 +129,22 @@ class RescuableTest < ActiveSupport::TestCase
 
   def test_rescue_from_with_method
     @stargate.dispatch :attack
-    assert_equal 'killed', @stargate.result
+    assert_equal "killed", @stargate.result
   end
 
   def test_rescue_from_with_block
     @stargate.dispatch :nuke
-    assert_equal 'alldead', @stargate.result
+    assert_equal "alldead", @stargate.result
   end
 
   def test_rescue_from_with_block_with_args
     @stargate.dispatch :ronanize
-    assert_equal 'dex', @stargate.result
+    assert_equal "dex", @stargate.result
   end
 
   def test_rescue_from_error_dispatchers_with_case_operator
     @stargate.dispatch :weird
-    assert_equal 'weird', @stargate.result
+    assert_equal "weird", @stargate.result
   end
 
   def test_rescues_defined_later_are_added_at_end_of_the_rescue_handlers_array
@@ -138,6 +161,16 @@ class RescuableTest < ActiveSupport::TestCase
 
   def test_rescue_falls_back_to_exception_cause
     @stargate.dispatch :fall_back_to_cause
-    assert_equal 'unhandled RuntimeError with a handleable cause', @stargate.result
+    assert_equal "dex", @stargate.result
+  end
+
+  def test_unhandled_exceptions
+    @stargate.dispatch(:crash)
+    assert_equal "unhandled", @stargate.result
+  end
+
+  def test_rescue_handles_loops_in_exception_cause_chain
+    @stargate.dispatch :looped_crash
+    assert_equal "unhandled", @stargate.result
   end
 end
diff --git a/activesupport/test/safe_buffer_test.rb b/activesupport/test/safe_buffer_test.rb
index 18fb6d2fbf..05c2fb59be 100644
--- a/activesupport/test/safe_buffer_test.rb
+++ b/activesupport/test/safe_buffer_test.rb
@@ -1,6 +1,8 @@
-require 'abstract_unit'
-require 'active_support/core_ext/string/inflections'
-require 'yaml'
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "active_support/core_ext/string/inflections"
+require "yaml"
 
 class SafeBufferTest < ActiveSupport::TestCase
   def setup
@@ -8,7 +10,7 @@ class SafeBufferTest < ActiveSupport::TestCase
   end
 
   def test_titleize
-    assert_equal 'Foo', "foo".html_safe.titleize
+    assert_equal "Foo", "foo".html_safe.titleize
   end
 
   test "Should look like a string" do
@@ -46,26 +48,26 @@ class SafeBufferTest < ActiveSupport::TestCase
   end
 
   test "Should be converted to_yaml" do
-    str  = 'hello!'
+    str  = "hello!"
     buf  = ActiveSupport::SafeBuffer.new str
     yaml = buf.to_yaml
 
     assert_match(/^--- #{str}/, yaml)
-    assert_equal 'hello!', YAML.load(yaml)
+    assert_equal "hello!", YAML.load(yaml)
   end
 
   test "Should work in nested to_yaml conversion" do
-    str  = 'hello!'
-    data = { 'str' => ActiveSupport::SafeBuffer.new(str) }
+    str  = "hello!"
+    data = { "str" => ActiveSupport::SafeBuffer.new(str) }
     yaml = YAML.dump data
-    assert_equal({'str' => str}, YAML.load(yaml))
+    assert_equal({ "str" => str }, YAML.load(yaml))
   end
 
   test "Should work with primitive-like-strings in to_yaml conversion" do
-    assert_equal 'true',  YAML.load(ActiveSupport::SafeBuffer.new('true').to_yaml)
-    assert_equal 'false', YAML.load(ActiveSupport::SafeBuffer.new('false').to_yaml)
-    assert_equal '1',     YAML.load(ActiveSupport::SafeBuffer.new('1').to_yaml)
-    assert_equal '1.1',   YAML.load(ActiveSupport::SafeBuffer.new('1.1').to_yaml)
+    assert_equal "true",  YAML.load(ActiveSupport::SafeBuffer.new("true").to_yaml)
+    assert_equal "false", YAML.load(ActiveSupport::SafeBuffer.new("false").to_yaml)
+    assert_equal "1",     YAML.load(ActiveSupport::SafeBuffer.new("1").to_yaml)
+    assert_equal "1.1",   YAML.load(ActiveSupport::SafeBuffer.new("1.1").to_yaml)
   end
 
   test "Should work with underscore" do
@@ -74,31 +76,31 @@ class SafeBufferTest < ActiveSupport::TestCase
   end
 
   test "Should not return safe buffer from gsub" do
-    altered_buffer = @buffer.gsub('', 'asdf')
-    assert_equal 'asdf', altered_buffer
+    altered_buffer = @buffer.gsub("", "asdf")
+    assert_equal "asdf", altered_buffer
     assert !altered_buffer.html_safe?
   end
 
   test "Should not return safe buffer from gsub!" do
-    @buffer.gsub!('', 'asdf')
-    assert_equal 'asdf', @buffer
+    @buffer.gsub!("", "asdf")
+    assert_equal "asdf", @buffer
     assert !@buffer.html_safe?
   end
 
   test "Should escape dirty buffers on add" do
     clean = "hello".html_safe
-    @buffer.gsub!('', '<>')
+    @buffer.gsub!("", "<>")
     assert_equal "hello&lt;&gt;", clean + @buffer
   end
 
   test "Should concat as a normal string when safe" do
     clean = "hello".html_safe
-    @buffer.gsub!('', '<>')
+    @buffer.gsub!("", "<>")
     assert_equal "<>hello", @buffer + clean
   end
 
   test "Should preserve html_safe? status on copy" do
-    @buffer.gsub!('', '<>')
+    @buffer.gsub!("", "<>")
     assert !@buffer.dup.html_safe?
   end
 
@@ -110,7 +112,7 @@ class SafeBufferTest < ActiveSupport::TestCase
   end
 
   test "Should raise an error when safe_concat is called on unsafe buffers" do
-    @buffer.gsub!('', '<>')
+    @buffer.gsub!("", "<>")
     assert_raise ActiveSupport::SafeBuffer::SafeConcatError do
       @buffer.safe_concat "BUSTED"
     end
@@ -121,22 +123,22 @@ class SafeBufferTest < ActiveSupport::TestCase
   end
 
   test "clone_empty returns an empty buffer" do
-    assert_equal '', ActiveSupport::SafeBuffer.new('foo').clone_empty
+    assert_equal "", ActiveSupport::SafeBuffer.new("foo").clone_empty
   end
 
   test "clone_empty keeps the original dirtyness" do
     assert @buffer.clone_empty.html_safe?
-    assert !@buffer.gsub!('', '').clone_empty.html_safe?
+    assert !@buffer.gsub!("", "").clone_empty.html_safe?
   end
 
   test "Should be safe when sliced if original value was safe" do
-    new_buffer = @buffer[0,0]
+    new_buffer = @buffer[0, 0]
     assert_not_nil new_buffer
     assert new_buffer.html_safe?, "should be safe"
   end
 
   test "Should continue unsafe on slice" do
-    x = 'foo'.html_safe.gsub!('f', '<script>alert("lolpwnd");</script>')
+    x = "foo".html_safe.gsub!("f", '<script>alert("lolpwnd");</script>')
 
     # calling gsub! makes the dirty flag true
     assert !x.html_safe?, "should not be safe"
@@ -148,33 +150,33 @@ class SafeBufferTest < ActiveSupport::TestCase
     assert !y.html_safe?, "should not be safe"
   end
 
-  test 'Should work with interpolation (array argument)' do
-    x = 'foo %s bar'.html_safe % ['qux']
-    assert_equal 'foo qux bar', x
+  test "Should work with interpolation (array argument)" do
+    x = "foo %s bar".html_safe % ["qux"]
+    assert_equal "foo qux bar", x
   end
 
-  test 'Should work with interpolation (hash argument)' do
-    x = 'foo %{x} bar'.html_safe % { x: 'qux' }
-    assert_equal 'foo qux bar', x
+  test "Should work with interpolation (hash argument)" do
+    x = "foo %{x} bar".html_safe % { x: "qux" }
+    assert_equal "foo qux bar", x
   end
 
-  test 'Should escape unsafe interpolated args' do
-    x = 'foo %{x} bar'.html_safe % { x: '<br/>' }
-    assert_equal 'foo &lt;br/&gt; bar', x
+  test "Should escape unsafe interpolated args" do
+    x = "foo %{x} bar".html_safe % { x: "<br/>" }
+    assert_equal "foo &lt;br/&gt; bar", x
   end
 
-  test 'Should not escape safe interpolated args' do
-    x = 'foo %{x} bar'.html_safe % { x: '<br/>'.html_safe }
-    assert_equal 'foo <br/> bar', x
+  test "Should not escape safe interpolated args" do
+    x = "foo %{x} bar".html_safe % { x: "<br/>".html_safe }
+    assert_equal "foo <br/> bar", x
   end
 
-  test 'Should interpolate to a safe string' do
-    x = 'foo %{x} bar'.html_safe % { x: 'qux' }
-    assert x.html_safe?, 'should be safe'
+  test "Should interpolate to a safe string" do
+    x = "foo %{x} bar".html_safe % { x: "qux" }
+    assert x.html_safe?, "should be safe"
   end
 
-  test 'Should not affect frozen objects when accessing characters' do
-    x = 'Hello'.html_safe
-    assert_equal x[/a/, 1], nil
+  test "Should not affect frozen objects when accessing characters" do
+    x = "Hello".html_safe
+    assert_nil x[/a/, 1]
   end
 end
diff --git a/activesupport/test/security_utils_test.rb b/activesupport/test/security_utils_test.rb
index 08d2e3baa6..0a607594a2 100644
--- a/activesupport/test/security_utils_test.rb
+++ b/activesupport/test/security_utils_test.rb
@@ -1,9 +1,22 @@
-require 'abstract_unit'
-require 'active_support/security_utils'
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "active_support/security_utils"
 
 class SecurityUtilsTest < ActiveSupport::TestCase
   def test_secure_compare_should_perform_string_comparison
-    assert ActiveSupport::SecurityUtils.secure_compare('a', 'a')
-    assert !ActiveSupport::SecurityUtils.secure_compare('a', 'b')
+    assert ActiveSupport::SecurityUtils.secure_compare("a", "a")
+    assert_not ActiveSupport::SecurityUtils.secure_compare("a", "b")
+  end
+
+  def test_fixed_length_secure_compare_should_perform_string_comparison
+    assert ActiveSupport::SecurityUtils.fixed_length_secure_compare("a", "a")
+    assert !ActiveSupport::SecurityUtils.fixed_length_secure_compare("a", "b")
+  end
+
+  def test_fixed_length_secure_compare_raise_on_length_mismatch
+    assert_raises(ArgumentError, "string length mismatch.") do
+      ActiveSupport::SecurityUtils.fixed_length_secure_compare("a", "ab")
+    end
   end
 end
diff --git a/activesupport/test/share_lock_test.rb b/activesupport/test/share_lock_test.rb
index acefa185a8..42fd5eefc1 100644
--- a/activesupport/test/share_lock_test.rb
+++ b/activesupport/test/share_lock_test.rb
@@ -1,6 +1,8 @@
-require 'abstract_unit'
-require 'concurrent/atomic/count_down_latch'
-require 'active_support/concurrency/share_lock'
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "concurrent/atomic/count_down_latch"
+require "active_support/concurrency/share_lock"
 
 class ShareLockTest < ActiveSupport::TestCase
   def setup
@@ -17,7 +19,7 @@ class ShareLockTest < ActiveSupport::TestCase
 
   def test_sharing_doesnt_block
     with_thread_waiting_in_lock_section(:sharing) do |sharing_thread_latch|
-      assert_threads_not_stuck(Thread.new {@lock.sharing {} })
+      assert_threads_not_stuck(Thread.new { @lock.sharing {} })
     end
   end
 
@@ -489,90 +491,90 @@ class ShareLockTest < ActiveSupport::TestCase
 
   private
 
-  module CustomAssertions
-    SUFFICIENT_TIMEOUT = 0.2
+    module CustomAssertions
+      SUFFICIENT_TIMEOUT = 0.2
 
-    private
+      private
 
-    def assert_threads_stuck_but_releasable_by_latch(threads, latch)
-      assert_threads_stuck threads
-      latch.count_down
-      assert_threads_not_stuck threads
-    end
+        def assert_threads_stuck_but_releasable_by_latch(threads, latch)
+          assert_threads_stuck threads
+          latch.count_down
+          assert_threads_not_stuck threads
+        end
 
-    def assert_threads_stuck(threads)
-      sleep(SUFFICIENT_TIMEOUT) # give threads time to do their business
-      assert(Array(threads).all? { |t| t.join(0.001).nil? })
-    end
+        def assert_threads_stuck(threads)
+          sleep(SUFFICIENT_TIMEOUT) # give threads time to do their business
+          assert(Array(threads).all? { |t| t.join(0.001).nil? })
+        end
 
-    def assert_threads_not_stuck(threads)
-      assert(Array(threads).all? { |t| t.join(SUFFICIENT_TIMEOUT) })
+        def assert_threads_not_stuck(threads)
+          assert(Array(threads).all? { |t| t.join(SUFFICIENT_TIMEOUT) })
+        end
     end
-  end
 
-  class CustomAssertionsTest < ActiveSupport::TestCase
-    include CustomAssertions
+    class CustomAssertionsTest < ActiveSupport::TestCase
+      include CustomAssertions
 
-    def setup
-      @latch = Concurrent::CountDownLatch.new
-      @thread = Thread.new { @latch.wait }
-    end
+      def setup
+        @latch = Concurrent::CountDownLatch.new
+        @thread = Thread.new { @latch.wait }
+      end
 
-    def teardown
-      @latch.count_down
-      @thread.join
-    end
+      def teardown
+        @latch.count_down
+        @thread.join
+      end
 
-    def test_happy_path
-      assert_threads_stuck_but_releasable_by_latch @thread, @latch
-    end
+      def test_happy_path
+        assert_threads_stuck_but_releasable_by_latch @thread, @latch
+      end
 
-    def test_detects_stuck_thread
-      assert_raises(Minitest::Assertion) do
-        assert_threads_not_stuck @thread
+      def test_detects_stuck_thread
+        assert_raises(Minitest::Assertion) do
+          assert_threads_not_stuck @thread
+        end
       end
-    end
 
-    def test_detects_free_thread
-      @latch.count_down
-      assert_raises(Minitest::Assertion) do
-        assert_threads_stuck @thread
+      def test_detects_free_thread
+        @latch.count_down
+        assert_raises(Minitest::Assertion) do
+          assert_threads_stuck @thread
+        end
       end
-    end
 
-    def test_detects_already_released
-      @latch.count_down
-      assert_raises(Minitest::Assertion) do
-        assert_threads_stuck_but_releasable_by_latch @thread, @latch
+      def test_detects_already_released
+        @latch.count_down
+        assert_raises(Minitest::Assertion) do
+          assert_threads_stuck_but_releasable_by_latch @thread, @latch
+        end
       end
-    end
 
-    def test_detects_remains_latched
-      another_latch = Concurrent::CountDownLatch.new
-      assert_raises(Minitest::Assertion) do
-        assert_threads_stuck_but_releasable_by_latch @thread, another_latch
+      def test_detects_remains_latched
+        another_latch = Concurrent::CountDownLatch.new
+        assert_raises(Minitest::Assertion) do
+          assert_threads_stuck_but_releasable_by_latch @thread, another_latch
+        end
       end
     end
-  end
 
-  include CustomAssertions
+    include CustomAssertions
 
-  def with_thread_waiting_in_lock_section(lock_section)
-    in_section      = Concurrent::CountDownLatch.new
-    section_release = Concurrent::CountDownLatch.new
+    def with_thread_waiting_in_lock_section(lock_section)
+      in_section      = Concurrent::CountDownLatch.new
+      section_release = Concurrent::CountDownLatch.new
 
-    stuck_thread = Thread.new do
-      @lock.send(lock_section) do
-        in_section.count_down
-        section_release.wait
+      stuck_thread = Thread.new do
+        @lock.send(lock_section) do
+          in_section.count_down
+          section_release.wait
+        end
       end
-    end
 
-    in_section.wait
+      in_section.wait
 
-    yield section_release
-  ensure
-    section_release.count_down
-    stuck_thread.join # clean up
-  end
+      yield section_release
+    ensure
+      section_release.count_down
+      stuck_thread.join # clean up
+    end
 end
diff --git a/activesupport/test/string_inquirer_test.rb b/activesupport/test/string_inquirer_test.rb
index a2ed577eb0..bf8f878a32 100644
--- a/activesupport/test/string_inquirer_test.rb
+++ b/activesupport/test/string_inquirer_test.rb
@@ -1,8 +1,10 @@
-require 'abstract_unit'
+# frozen_string_literal: true
+
+require "abstract_unit"
 
 class StringInquirerTest < ActiveSupport::TestCase
   def setup
-    @string_inquirer = ActiveSupport::StringInquirer.new('production')
+    @string_inquirer = ActiveSupport::StringInquirer.new("production")
   end
 
   def test_match
@@ -20,4 +22,25 @@ class StringInquirerTest < ActiveSupport::TestCase
   def test_respond_to
     assert_respond_to @string_inquirer, :development?
   end
+
+  def test_respond_to_fallback_to_string_respond_to
+    String.class_eval do
+      def respond_to_missing?(name, include_private = false)
+        (name == :bar) || super
+      end
+    end
+    str = ActiveSupport::StringInquirer.new("hello")
+
+    assert_respond_to str, :are_you_ready?
+    assert_respond_to str, :bar
+    assert_not_respond_to str, :nope
+
+  ensure
+    String.class_eval do
+      undef_method :respond_to_missing?
+      def respond_to_missing?(name, include_private = false)
+        super
+      end
+    end
+  end
 end
diff --git a/activesupport/test/subscriber_test.rb b/activesupport/test/subscriber_test.rb
index a88d8d9eba..6b012e43af 100644
--- a/activesupport/test/subscriber_test.rb
+++ b/activesupport/test/subscriber_test.rb
@@ -1,5 +1,7 @@
-require 'abstract_unit'
-require 'active_support/subscriber'
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "active_support/subscriber"
 
 class TestSubscriber < ActiveSupport::Subscriber
   attach_to :doodle
@@ -16,9 +18,9 @@ class TestSubscriber < ActiveSupport::Subscriber
 
   private
 
-  def private_party(event)
-    events << event
-  end
+    def private_party(event)
+      events << event
+    end
 end
 
 # Monkey patch subscriber to test that only one subscriber per method is added.
diff --git a/activesupport/test/tagged_logging_test.rb b/activesupport/test/tagged_logging_test.rb
index 917fa46c96..5fd6a6b316 100644
--- a/activesupport/test/tagged_logging_test.rb
+++ b/activesupport/test/tagged_logging_test.rb
@@ -1,6 +1,8 @@
-require 'abstract_unit'
-require 'active_support/logger'
-require 'active_support/tagged_logging'
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "active_support/logger"
+require "active_support/tagged_logging"
 
 class TaggedLoggingTest < ActiveSupport::TestCase
   class MyLogger < ::ActiveSupport::Logger
@@ -14,7 +16,7 @@ class TaggedLoggingTest < ActiveSupport::TestCase
     @logger = ActiveSupport::TaggedLogging.new(MyLogger.new(@output))
   end
 
-  test 'sets logger.formatter if missing and extends it with a tagging API' do
+  test "sets logger.formatter if missing and extends it with a tagging API" do
     logger = Logger.new(StringIO.new)
     assert_nil logger.formatter
     ActiveSupport::TaggedLogging.new(logger)
@@ -43,14 +45,14 @@ class TaggedLoggingTest < ActiveSupport::TestCase
   end
 
   test "push and pop tags directly" do
-    assert_equal %w(A B C), @logger.push_tags('A', ['B', '  ', ['C']])
-    @logger.info 'a'
+    assert_equal %w(A B C), @logger.push_tags("A", ["B", "  ", ["C"]])
+    @logger.info "a"
     assert_equal %w(C), @logger.pop_tags
-    @logger.info 'b'
+    @logger.info "b"
     assert_equal %w(B), @logger.pop_tags(1)
-    @logger.info 'c'
+    @logger.info "c"
     assert_equal [], @logger.clear_tags!
-    @logger.info 'd'
+    @logger.info "d"
     assert_equal "[A] [B] [C] a\n[A] [B] b\n[A] c\nd\n", @output.string
   end
 
diff --git a/activesupport/test/test_case_test.rb b/activesupport/test/test_case_test.rb
index 18228a2ac5..84e4953fe2 100644
--- a/activesupport/test/test_case_test.rb
+++ b/activesupport/test/test_case_test.rb
@@ -1,4 +1,6 @@
-require 'abstract_unit'
+# frozen_string_literal: true
+
+require "abstract_unit"
 
 class AssertDifferenceTest < ActiveSupport::TestCase
   def setup
@@ -20,21 +22,21 @@ class AssertDifferenceTest < ActiveSupport::TestCase
     assert_equal true, assert_not(false)
 
     e = assert_raises(Minitest::Assertion) { assert_not true }
-    assert_equal 'Expected true to be nil or false', e.message
+    assert_equal "Expected true to be nil or false", e.message
 
-    e = assert_raises(Minitest::Assertion) { assert_not true, 'custom' }
-    assert_equal 'custom', e.message
+    e = assert_raises(Minitest::Assertion) { assert_not true, "custom" }
+    assert_equal "custom", e.message
   end
 
   def test_assert_no_difference_pass
-    assert_no_difference '@object.num' do
+    assert_no_difference "@object.num" do
       # ...
     end
   end
 
   def test_assert_no_difference_fail
     error = assert_raises(Minitest::Assertion) do
-      assert_no_difference '@object.num' do
+      assert_no_difference "@object.num" do
         @object.increment
       end
     end
@@ -43,7 +45,7 @@ class AssertDifferenceTest < ActiveSupport::TestCase
 
   def test_assert_no_difference_with_message_fail
     error = assert_raises(Minitest::Assertion) do
-      assert_no_difference '@object.num', 'Object Changed' do
+      assert_no_difference "@object.num", "Object Changed" do
         @object.increment
       end
     end
@@ -51,13 +53,13 @@ class AssertDifferenceTest < ActiveSupport::TestCase
   end
 
   def test_assert_difference
-    assert_difference '@object.num', +1 do
+    assert_difference "@object.num", +1 do
       @object.increment
     end
   end
 
   def test_assert_difference_retval
-    incremented = assert_difference '@object.num', +1 do
+    incremented = assert_difference "@object.num", +1 do
       @object.increment
     end
 
@@ -65,40 +67,41 @@ class AssertDifferenceTest < ActiveSupport::TestCase
   end
 
   def test_assert_difference_with_implicit_difference
-    assert_difference '@object.num' do
+    assert_difference "@object.num" do
       @object.increment
     end
   end
 
   def test_arbitrary_expression
-    assert_difference '@object.num + 1', +2 do
+    assert_difference "@object.num + 1", +2 do
       @object.increment
       @object.increment
     end
   end
 
   def test_negative_differences
-    assert_difference '@object.num', -1 do
+    assert_difference "@object.num", -1 do
       @object.decrement
     end
   end
 
   def test_expression_is_evaluated_in_the_appropriate_scope
     silence_warnings do
-      local_scope = local_scope = 'foo'
-      assert_difference('local_scope; @object.num') { @object.increment }
+      local_scope = "foo"
+      local_scope = local_scope  # to suppress unused variable warning
+      assert_difference("local_scope; @object.num") { @object.increment }
     end
   end
 
   def test_array_of_expressions
-    assert_difference [ '@object.num', '@object.num + 1' ], +1 do
+    assert_difference [ "@object.num", "@object.num + 1" ], +1 do
       @object.increment
     end
   end
 
   def test_array_of_expressions_identify_failure
     assert_raises(Minitest::Assertion) do
-      assert_difference ['@object.num', '1 + 1'] do
+      assert_difference ["@object.num", "1 + 1"] do
         @object.increment
       end
     end
@@ -106,14 +109,136 @@ class AssertDifferenceTest < ActiveSupport::TestCase
 
   def test_array_of_expressions_identify_failure_when_message_provided
     assert_raises(Minitest::Assertion) do
-      assert_difference ['@object.num', '1 + 1'], 1, 'something went wrong' do
+      assert_difference ["@object.num", "1 + 1"], 1, "something went wrong" do
         @object.increment
       end
     end
   end
-end
 
-class AlsoDoingNothingTest < ActiveSupport::TestCase
+  def test_assert_changes_pass
+    assert_changes "@object.num" do
+      @object.increment
+    end
+  end
+
+  def test_assert_changes_pass_with_lambda
+    assert_changes -> { @object.num } do
+      @object.increment
+    end
+  end
+
+  def test_assert_changes_with_from_option
+    assert_changes "@object.num", from: 0 do
+      @object.increment
+    end
+  end
+
+  def test_assert_changes_with_from_option_with_wrong_value
+    assert_raises Minitest::Assertion do
+      assert_changes "@object.num", from: -1 do
+        @object.increment
+      end
+    end
+  end
+
+  def test_assert_changes_with_from_option_with_nil
+    error = assert_raises Minitest::Assertion do
+      assert_changes "@object.num", from: nil do
+        @object.increment
+      end
+    end
+    assert_equal "\"@object.num\" isn't nil", error.message
+  end
+
+  def test_assert_changes_with_to_option
+    assert_changes "@object.num", to: 1 do
+      @object.increment
+    end
+  end
+
+  def test_assert_changes_with_wrong_to_option
+    assert_raises Minitest::Assertion do
+      assert_changes "@object.num", to: 2 do
+        @object.increment
+      end
+    end
+  end
+
+  def test_assert_changes_with_from_option_and_to_option
+    assert_changes "@object.num", from: 0, to: 1 do
+      @object.increment
+    end
+  end
+
+  def test_assert_changes_with_from_and_to_options_and_wrong_to_value
+    assert_raises Minitest::Assertion do
+      assert_changes "@object.num", from: 0, to: 2 do
+        @object.increment
+      end
+    end
+  end
+
+  def test_assert_changes_works_with_any_object
+    # Silences: instance variable @new_object not initialized.
+    retval = silence_warnings do
+      assert_changes :@new_object, from: nil, to: 42 do
+        @new_object = 42
+      end
+    end
+
+    assert_equal 42, retval
+  end
+
+  def test_assert_changes_works_with_nil
+    oldval = @object
+
+    retval = assert_changes :@object, from: oldval, to: nil do
+      @object = nil
+    end
+
+    assert_nil retval
+  end
+
+  def test_assert_changes_with_to_and_case_operator
+    token = nil
+
+    assert_changes -> { token }, to: /\w{32}/ do
+      token = SecureRandom.hex
+    end
+  end
+
+  def test_assert_changes_with_to_and_from_and_case_operator
+    token = SecureRandom.hex
+
+    assert_changes -> { token }, from: /\w{32}/, to: /\w{32}/ do
+      token = SecureRandom.hex
+    end
+  end
+
+  def test_assert_changes_with_message
+    error = assert_raises Minitest::Assertion do
+      assert_changes "@object.num", "@object.num should 1", to: 1 do
+      end
+    end
+
+    assert_equal "@object.num should 1.\n\"@object.num\" didn't change to 1", error.message
+  end
+
+  def test_assert_no_changes_pass
+    assert_no_changes "@object.num" do
+      # ...
+    end
+  end
+
+  def test_assert_no_changes_with_message
+    error = assert_raises Minitest::Assertion do
+      assert_no_changes "@object.num", "@object.num should not change" do
+        @object.increment
+      end
+    end
+
+    assert_equal "@object.num should not change.\n\"@object.num\" did change to 1", error.message
+  end
 end
 
 # Setup and teardown callbacks.
@@ -133,7 +258,7 @@ class SetupAndTeardownTest < ActiveSupport::TestCase
   def teardown
   end
 
-  protected
+  private
 
     def reset_callback_record
       @called_back = []
@@ -158,7 +283,7 @@ class SubclassSetupAndTeardownTest < SetupAndTeardownTest
     assert_equal [:foo, :sentinel, :bar], self.class._teardown_callbacks.map(&:raw_filter)
   end
 
-  protected
+  private
     def bar
       @called_back << :bar
     end
@@ -170,7 +295,7 @@ end
 
 class TestCaseTaggedLoggingTest < ActiveSupport::TestCase
   def before_setup
-    require 'stringio'
+    require "stringio"
     @out = StringIO.new
     self.tagged_logger = ActiveSupport::TaggedLogging.new(Logger.new(@out))
     super
diff --git a/activesupport/test/testing/constant_lookup_test.rb b/activesupport/test/testing/constant_lookup_test.rb
index 0f16419c8b..37b7822950 100644
--- a/activesupport/test/testing/constant_lookup_test.rb
+++ b/activesupport/test/testing/constant_lookup_test.rb
@@ -1,5 +1,7 @@
-require 'abstract_unit'
-require 'dependencies_test_helpers'
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "dependencies_test_helpers"
 
 class Foo; end
 class Bar < Foo
@@ -69,7 +71,7 @@ class ConstantLookupTest < ActiveSupport::TestCase
   def test_does_not_swallow_exception_on_no_name_error_within_constant
     assert_raises(NameError) do
       with_autoloading_fixtures do
-        self.class.determine_constant_from_test_name('RaisesNameError')
+        self.class.determine_constant_from_test_name("RaisesNameError")
       end
     end
   end
diff --git a/activesupport/test/testing/file_fixtures_test.rb b/activesupport/test/testing/file_fixtures_test.rb
index 91b8a9071c..35be8f5206 100644
--- a/activesupport/test/testing/file_fixtures_test.rb
+++ b/activesupport/test/testing/file_fixtures_test.rb
@@ -1,12 +1,16 @@
-require 'abstract_unit'
+# frozen_string_literal: true
+
+require "abstract_unit"
+
+require "pathname"
 
 class FileFixturesTest < ActiveSupport::TestCase
-  self.file_fixture_path = File.expand_path("../../file_fixtures", __FILE__)
+  self.file_fixture_path = File.expand_path("../file_fixtures", __dir__)
 
   test "#file_fixture returns Pathname to file fixture" do
     path = file_fixture("sample.txt")
     assert_kind_of Pathname, path
-    assert_match %r{activesupport/test/file_fixtures/sample.txt$}, path.to_s
+    assert_match %r{.*/test/file_fixtures/sample\.txt$}, path.to_s
   end
 
   test "raises an exception when the fixture file does not exist" do
@@ -18,11 +22,11 @@ class FileFixturesTest < ActiveSupport::TestCase
 end
 
 class FileFixturesPathnameDirectoryTest < ActiveSupport::TestCase
-  self.file_fixture_path = Pathname.new(File.expand_path("../../file_fixtures", __FILE__))
+  self.file_fixture_path = Pathname.new(File.expand_path("../file_fixtures", __dir__))
 
   test "#file_fixture_path returns Pathname to file fixture" do
     path = file_fixture("sample.txt")
     assert_kind_of Pathname, path
-    assert_match %r{activesupport/test/file_fixtures/sample.txt$}, path.to_s
+    assert_match %r{.*/test/file_fixtures/sample\.txt$}, path.to_s
   end
 end
diff --git a/activesupport/test/testing/method_call_assertions_test.rb b/activesupport/test/testing/method_call_assertions_test.rb
index 3e5ba7c079..4af000bb7e 100644
--- a/activesupport/test/testing/method_call_assertions_test.rb
+++ b/activesupport/test/testing/method_call_assertions_test.rb
@@ -1,5 +1,7 @@
-require 'abstract_unit'
-require 'active_support/testing/method_call_assertions'
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "active_support/testing/method_call_assertions"
 
 class MethodCallAssertionsTest < ActiveSupport::TestCase
   include ActiveSupport::Testing::MethodCallAssertions
@@ -51,7 +53,7 @@ class MethodCallAssertionsTest < ActiveSupport::TestCase
 
   def test_assert_called_with_message
     error = assert_raises(Minitest::Assertion) do
-      assert_called(@object, :increment, 'dang it') do
+      assert_called(@object, :increment, "dang it") do
         # Call nothing...
       end
     end
diff --git a/activesupport/test/time_travel_test.rb b/activesupport/test/time_travel_test.rb
index 59c3e52c2f..9c2c635f43 100644
--- a/activesupport/test/time_travel_test.rb
+++ b/activesupport/test/time_travel_test.rb
@@ -1,20 +1,26 @@
-require 'abstract_unit'
-require 'active_support/core_ext/date_time'
-require 'active_support/core_ext/numeric/time'
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "active_support/core_ext/date_time"
+require "active_support/core_ext/numeric/time"
 
 class TimeTravelTest < ActiveSupport::TestCase
-  teardown do
-    travel_back
-  end
+  class TimeSubclass < ::Time; end
+  class DateSubclass < ::Date; end
+  class DateTimeSubclass < ::DateTime; end
 
   def test_time_helper_travel
     Time.stub(:now, Time.now) do
-      expected_time = Time.now + 1.day
-      travel 1.day
+      begin
+        expected_time = Time.now + 1.day
+        travel 1.day
 
-      assert_equal expected_time.to_s(:db), Time.now.to_s(:db)
-      assert_equal expected_time.to_date, Date.today
-      assert_equal expected_time.to_datetime.to_s(:db), DateTime.now.to_s(:db)
+        assert_equal expected_time.to_s(:db), Time.now.to_s(:db)
+        assert_equal expected_time.to_date, Date.today
+        assert_equal expected_time.to_datetime.to_s(:db), DateTime.now.to_s(:db)
+      ensure
+        travel_back
+      end
     end
   end
 
@@ -36,12 +42,16 @@ class TimeTravelTest < ActiveSupport::TestCase
 
   def test_time_helper_travel_to
     Time.stub(:now, Time.now) do
-      expected_time = Time.new(2004, 11, 24, 01, 04, 44)
-      travel_to expected_time
+      begin
+        expected_time = Time.new(2004, 11, 24, 01, 04, 44)
+        travel_to expected_time
 
-      assert_equal expected_time, Time.now
-      assert_equal Date.new(2004, 11, 24), Date.today
-      assert_equal expected_time.to_datetime, DateTime.now
+        assert_equal expected_time, Time.now
+        assert_equal Date.new(2004, 11, 24), Date.today
+        assert_equal expected_time.to_datetime, DateTime.now
+      ensure
+        travel_back
+      end
     end
   end
 
@@ -63,17 +73,69 @@ class TimeTravelTest < ActiveSupport::TestCase
 
   def test_time_helper_travel_back
     Time.stub(:now, Time.now) do
-      expected_time = Time.new(2004, 11, 24, 01, 04, 44)
+      begin
+        expected_time = Time.new(2004, 11, 24, 01, 04, 44)
 
-      travel_to expected_time
-      assert_equal expected_time, Time.now
-      assert_equal Date.new(2004, 11, 24), Date.today
-      assert_equal expected_time.to_datetime, DateTime.now
-      travel_back
+        travel_to expected_time
+        assert_equal expected_time, Time.now
+        assert_equal Date.new(2004, 11, 24), Date.today
+        assert_equal expected_time.to_datetime, DateTime.now
+        travel_back
 
-      assert_not_equal expected_time, Time.now
-      assert_not_equal Date.new(2004, 11, 24), Date.today
-      assert_not_equal expected_time.to_datetime, DateTime.now
+        assert_not_equal expected_time, Time.now
+        assert_not_equal Date.new(2004, 11, 24), Date.today
+        assert_not_equal expected_time.to_datetime, DateTime.now
+      ensure
+        travel_back
+      end
+    end
+  end
+
+  def test_time_helper_travel_to_with_nested_calls_with_blocks
+    Time.stub(:now, Time.now) do
+      outer_expected_time = Time.new(2004, 11, 24, 01, 04, 44)
+      inner_expected_time = Time.new(2004, 10, 24, 01, 04, 44)
+      travel_to outer_expected_time do
+        e = assert_raises(RuntimeError) do
+          travel_to(inner_expected_time) do
+            # noop
+          end
+        end
+        assert_match(/Calling `travel_to` with a block, when we have previously already made a call to `travel_to`, can lead to confusing time stubbing\./, e.message)
+      end
+    end
+  end
+
+  def test_time_helper_travel_to_with_nested_calls
+    Time.stub(:now, Time.now) do
+      outer_expected_time = Time.new(2004, 11, 24, 01, 04, 44)
+      inner_expected_time = Time.new(2004, 10, 24, 01, 04, 44)
+      travel_to outer_expected_time do
+        assert_nothing_raised do
+          travel_to(inner_expected_time)
+
+          assert_equal inner_expected_time, Time.now
+        end
+      end
+    end
+  end
+
+  def test_time_helper_travel_to_with_subsequent_calls
+    Time.stub(:now, Time.now) do
+      begin
+        initial_expected_time = Time.new(2004, 11, 24, 01, 04, 44)
+        subsequent_expected_time = Time.new(2004, 10, 24, 01, 04, 44)
+        assert_nothing_raised do
+          travel_to initial_expected_time
+          travel_to subsequent_expected_time
+
+          assert_equal subsequent_expected_time, Time.now
+
+          travel_back
+        end
+      ensure
+        travel_back
+      end
     end
   end
 
@@ -87,4 +149,41 @@ class TimeTravelTest < ActiveSupport::TestCase
       end
     end
   end
+
+  def test_time_helper_travel_with_time_subclass
+    assert_equal TimeSubclass, TimeSubclass.now.class
+    assert_equal DateSubclass, DateSubclass.today.class
+    assert_equal DateTimeSubclass, DateTimeSubclass.now.class
+
+    travel 1.day do
+      assert_equal TimeSubclass, TimeSubclass.now.class
+      assert_equal DateSubclass, DateSubclass.today.class
+      assert_equal DateTimeSubclass, DateTimeSubclass.now.class
+      assert_equal Time.now.to_s, TimeSubclass.now.to_s
+      assert_equal Date.today.to_s, DateSubclass.today.to_s
+      assert_equal DateTime.now.to_s, DateTimeSubclass.now.to_s
+    end
+  end
+
+  def test_time_helper_freeze_time
+    expected_time = Time.now
+    freeze_time
+    sleep(1)
+
+    assert_equal expected_time.to_s(:db), Time.now.to_s(:db)
+  ensure
+    travel_back
+  end
+
+  def test_time_helper_freeze_time_with_block
+    expected_time = Time.now
+
+    freeze_time do
+      sleep(1)
+
+      assert_equal expected_time.to_s(:db), Time.now.to_s(:db)
+    end
+
+    assert_operator expected_time.to_s(:db), :<, Time.now.to_s(:db)
+  end
 end
diff --git a/activesupport/test/time_zone_test.rb b/activesupport/test/time_zone_test.rb
index a15d5c6a0e..405c8f315b 100644
--- a/activesupport/test/time_zone_test.rb
+++ b/activesupport/test/time_zone_test.rb
@@ -1,25 +1,27 @@
-require 'abstract_unit'
-require 'active_support/time'
-require 'time_zone_test_helpers'
-require 'yaml'
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "active_support/time"
+require "time_zone_test_helpers"
+require "yaml"
 
 class TimeZoneTest < ActiveSupport::TestCase
   include TimeZoneTestHelpers
 
   def test_utc_to_local
-    zone = ActiveSupport::TimeZone['Eastern Time (US & Canada)']
+    zone = ActiveSupport::TimeZone["Eastern Time (US & Canada)"]
     assert_equal Time.utc(1999, 12, 31, 19), zone.utc_to_local(Time.utc(2000, 1)) # standard offset -0500
     assert_equal Time.utc(2000, 6, 30, 20), zone.utc_to_local(Time.utc(2000, 7)) # dst offset -0400
   end
 
   def test_local_to_utc
-    zone = ActiveSupport::TimeZone['Eastern Time (US & Canada)']
+    zone = ActiveSupport::TimeZone["Eastern Time (US & Canada)"]
     assert_equal Time.utc(2000, 1, 1, 5), zone.local_to_utc(Time.utc(2000, 1)) # standard offset -0500
     assert_equal Time.utc(2000, 7, 1, 4), zone.local_to_utc(Time.utc(2000, 7)) # dst offset -0400
   end
 
   def test_period_for_local
-    zone = ActiveSupport::TimeZone['Eastern Time (US & Canada)']
+    zone = ActiveSupport::TimeZone["Eastern Time (US & Canada)"]
     assert_instance_of TZInfo::TimezonePeriod, zone.period_for_local(Time.utc(2000))
   end
 
@@ -30,6 +32,12 @@ class TimeZoneTest < ActiveSupport::TestCase
     end
   end
 
+  def test_period_for_local_with_ambigiuous_time
+    zone = ActiveSupport::TimeZone["Moscow"]
+    period = zone.period_for_local(Time.utc(2015, 1, 1))
+    assert_equal period, zone.period_for_local(Time.utc(2014, 10, 26, 1, 0, 0))
+  end
+
   def test_from_integer_to_map
     assert_instance_of ActiveSupport::TimeZone, ActiveSupport::TimeZone[-28800] # PST
   end
@@ -39,7 +47,7 @@ class TimeZoneTest < ActiveSupport::TestCase
   end
 
   ActiveSupport::TimeZone.all.each do |zone|
-    name = zone.name.downcase.gsub(/[^a-z]/, '_')
+    name = zone.name.downcase.gsub(/[^a-z]/, "_")
     define_method("test_from_#{name}_to_map") do
       assert_instance_of ActiveSupport::TimeZone, ActiveSupport::TimeZone[zone.name]
     end
@@ -51,86 +59,83 @@ class TimeZoneTest < ActiveSupport::TestCase
   end
 
   def test_now
-    with_env_tz 'US/Eastern' do
-      zone = ActiveSupport::TimeZone['Eastern Time (US & Canada)'].dup
+    with_env_tz "US/Eastern" do
+      zone = ActiveSupport::TimeZone["Eastern Time (US & Canada)"].dup
       def zone.time_now; Time.local(2000); end
       assert_instance_of ActiveSupport::TimeWithZone, zone.now
-      assert_equal Time.utc(2000,1,1,5), zone.now.utc
+      assert_equal Time.utc(2000, 1, 1, 5), zone.now.utc
       assert_equal Time.utc(2000), zone.now.time
       assert_equal zone, zone.now.time_zone
     end
   end
 
   def test_now_enforces_spring_dst_rules
-    with_env_tz 'US/Eastern' do
-      zone = ActiveSupport::TimeZone['Eastern Time (US & Canada)'].dup
+    with_env_tz "US/Eastern" do
+      zone = ActiveSupport::TimeZone["Eastern Time (US & Canada)"].dup
       def zone.time_now
-        Time.local(2006,4,2,2) # 2AM springs forward to 3AM
+        Time.local(2006, 4, 2, 2) # 2AM springs forward to 3AM
       end
 
-      assert_equal Time.utc(2006,4,2,3), zone.now.time
+      assert_equal Time.utc(2006, 4, 2, 3), zone.now.time
       assert_equal true, zone.now.dst?
     end
   end
 
   def test_now_enforces_fall_dst_rules
-    with_env_tz 'US/Eastern' do
-      zone = ActiveSupport::TimeZone['Eastern Time (US & Canada)'].dup
+    with_env_tz "US/Eastern" do
+      zone = ActiveSupport::TimeZone["Eastern Time (US & Canada)"].dup
       def zone.time_now
         Time.at(1162098000) # equivalent to 1AM DST
       end
-      assert_equal Time.utc(2006,10,29,1), zone.now.time
+      assert_equal Time.utc(2006, 10, 29, 1), zone.now.time
       assert_equal true, zone.now.dst?
     end
   end
 
   def test_unknown_timezones_delegation_to_tzinfo
-    zone = ActiveSupport::TimeZone['America/Montevideo']
+    zone = ActiveSupport::TimeZone["America/Montevideo"]
     assert_equal ActiveSupport::TimeZone, zone.class
-    assert_equal zone.object_id, ActiveSupport::TimeZone['America/Montevideo'].object_id
+    assert_equal zone.object_id, ActiveSupport::TimeZone["America/Montevideo"].object_id
     assert_equal Time.utc(2010, 1, 31, 22), zone.utc_to_local(Time.utc(2010, 2)) # daylight saving offset -0200
     assert_equal Time.utc(2010, 3, 31, 21), zone.utc_to_local(Time.utc(2010, 4)) # standard offset -0300
   end
 
   def test_today
     travel_to(Time.utc(2000, 1, 1, 4, 59, 59)) # 1 sec before midnight Jan 1 EST
-    assert_equal Date.new(1999, 12, 31), ActiveSupport::TimeZone['Eastern Time (US & Canada)'].today
+    assert_equal Date.new(1999, 12, 31), ActiveSupport::TimeZone["Eastern Time (US & Canada)"].today
     travel_to(Time.utc(2000, 1, 1, 5)) # midnight Jan 1 EST
-    assert_equal Date.new(2000, 1, 1), ActiveSupport::TimeZone['Eastern Time (US & Canada)'].today
+    assert_equal Date.new(2000, 1, 1), ActiveSupport::TimeZone["Eastern Time (US & Canada)"].today
     travel_to(Time.utc(2000, 1, 2, 4, 59, 59)) # 1 sec before midnight Jan 2 EST
-    assert_equal Date.new(2000, 1, 1), ActiveSupport::TimeZone['Eastern Time (US & Canada)'].today
+    assert_equal Date.new(2000, 1, 1), ActiveSupport::TimeZone["Eastern Time (US & Canada)"].today
     travel_to(Time.utc(2000, 1, 2, 5)) # midnight Jan 2 EST
-    assert_equal Date.new(2000, 1, 2), ActiveSupport::TimeZone['Eastern Time (US & Canada)'].today
-    travel_back
+    assert_equal Date.new(2000, 1, 2), ActiveSupport::TimeZone["Eastern Time (US & Canada)"].today
   end
 
   def test_tomorrow
     travel_to(Time.utc(2000, 1, 1, 4, 59, 59)) # 1 sec before midnight Jan 1 EST
-    assert_equal Date.new(2000, 1, 1), ActiveSupport::TimeZone['Eastern Time (US & Canada)'].tomorrow
+    assert_equal Date.new(2000, 1, 1), ActiveSupport::TimeZone["Eastern Time (US & Canada)"].tomorrow
     travel_to(Time.utc(2000, 1, 1, 5)) # midnight Jan 1 EST
-    assert_equal Date.new(2000, 1, 2), ActiveSupport::TimeZone['Eastern Time (US & Canada)'].tomorrow
+    assert_equal Date.new(2000, 1, 2), ActiveSupport::TimeZone["Eastern Time (US & Canada)"].tomorrow
     travel_to(Time.utc(2000, 1, 2, 4, 59, 59)) # 1 sec before midnight Jan 2 EST
-    assert_equal Date.new(2000, 1, 2), ActiveSupport::TimeZone['Eastern Time (US & Canada)'].tomorrow
+    assert_equal Date.new(2000, 1, 2), ActiveSupport::TimeZone["Eastern Time (US & Canada)"].tomorrow
     travel_to(Time.utc(2000, 1, 2, 5)) # midnight Jan 2 EST
-    assert_equal Date.new(2000, 1, 3), ActiveSupport::TimeZone['Eastern Time (US & Canada)'].tomorrow
-    travel_back
+    assert_equal Date.new(2000, 1, 3), ActiveSupport::TimeZone["Eastern Time (US & Canada)"].tomorrow
   end
 
   def test_yesterday
     travel_to(Time.utc(2000, 1, 1, 4, 59, 59)) # 1 sec before midnight Jan 1 EST
-    assert_equal Date.new(1999, 12, 30), ActiveSupport::TimeZone['Eastern Time (US & Canada)'].yesterday
+    assert_equal Date.new(1999, 12, 30), ActiveSupport::TimeZone["Eastern Time (US & Canada)"].yesterday
     travel_to(Time.utc(2000, 1, 1, 5)) # midnight Jan 1 EST
-    assert_equal Date.new(1999, 12, 31), ActiveSupport::TimeZone['Eastern Time (US & Canada)'].yesterday
+    assert_equal Date.new(1999, 12, 31), ActiveSupport::TimeZone["Eastern Time (US & Canada)"].yesterday
     travel_to(Time.utc(2000, 1, 2, 4, 59, 59)) # 1 sec before midnight Jan 2 EST
-    assert_equal Date.new(1999, 12, 31), ActiveSupport::TimeZone['Eastern Time (US & Canada)'].yesterday
+    assert_equal Date.new(1999, 12, 31), ActiveSupport::TimeZone["Eastern Time (US & Canada)"].yesterday
     travel_to(Time.utc(2000, 1, 2, 5)) # midnight Jan 2 EST
-    assert_equal Date.new(2000, 1, 1), ActiveSupport::TimeZone['Eastern Time (US & Canada)'].yesterday
-    travel_back
+    assert_equal Date.new(2000, 1, 1), ActiveSupport::TimeZone["Eastern Time (US & Canada)"].yesterday
   end
 
   def test_travel_to_a_date
     with_env_tz do
-      Time.use_zone('Hawaii') do
+      Time.use_zone("Hawaii") do
         date = Date.new(2014, 2, 18)
         time = date.midnight
 
@@ -162,52 +167,57 @@ class TimeZoneTest < ActiveSupport::TestCase
 
   def test_local_with_old_date
     time = ActiveSupport::TimeZone["Hawaii"].local(1850, 2, 5, 15, 30, 45)
-    assert_equal [45,30,15,5,2,1850], time.to_a[0,6]
+    assert_equal [45, 30, 15, 5, 2, 1850], time.to_a[0, 6]
     assert_equal ActiveSupport::TimeZone["Hawaii"], time.time_zone
   end
 
   def test_local_enforces_spring_dst_rules
-    zone = ActiveSupport::TimeZone['Eastern Time (US & Canada)']
-    twz = zone.local(2006,4,2,1,59,59) # 1 second before DST start
-    assert_equal Time.utc(2006,4,2,1,59,59), twz.time
-    assert_equal Time.utc(2006,4,2,6,59,59), twz.utc
+    zone = ActiveSupport::TimeZone["Eastern Time (US & Canada)"]
+    twz = zone.local(2006, 4, 2, 1, 59, 59) # 1 second before DST start
+    assert_equal Time.utc(2006, 4, 2, 1, 59, 59), twz.time
+    assert_equal Time.utc(2006, 4, 2, 6, 59, 59), twz.utc
     assert_equal false, twz.dst?
-    assert_equal 'EST', twz.zone
-    twz2 = zone.local(2006,4,2,2) # 2AM does not exist because at 2AM, time springs forward to 3AM
-    assert_equal Time.utc(2006,4,2,3), twz2.time # twz is created for 3AM
-    assert_equal Time.utc(2006,4,2,7), twz2.utc
+    assert_equal "EST", twz.zone
+    twz2 = zone.local(2006, 4, 2, 2) # 2AM does not exist because at 2AM, time springs forward to 3AM
+    assert_equal Time.utc(2006, 4, 2, 3), twz2.time # twz is created for 3AM
+    assert_equal Time.utc(2006, 4, 2, 7), twz2.utc
     assert_equal true, twz2.dst?
-    assert_equal 'EDT', twz2.zone
-    twz3 = zone.local(2006,4,2,2,30) # 2:30AM does not exist because at 2AM, time springs forward to 3AM
-    assert_equal Time.utc(2006,4,2,3,30), twz3.time # twz is created for 3:30AM
-    assert_equal Time.utc(2006,4,2,7,30), twz3.utc
+    assert_equal "EDT", twz2.zone
+    twz3 = zone.local(2006, 4, 2, 2, 30) # 2:30AM does not exist because at 2AM, time springs forward to 3AM
+    assert_equal Time.utc(2006, 4, 2, 3, 30), twz3.time # twz is created for 3:30AM
+    assert_equal Time.utc(2006, 4, 2, 7, 30), twz3.utc
     assert_equal true, twz3.dst?
-    assert_equal 'EDT', twz3.zone
+    assert_equal "EDT", twz3.zone
   end
 
   def test_local_enforces_fall_dst_rules
     # 1AM during fall DST transition is ambiguous, it could be either DST or non-DST 1AM
     # Mirroring Time.local behavior, this method selects the DST time
-    zone = ActiveSupport::TimeZone['Eastern Time (US & Canada)']
-    twz = zone.local(2006,10,29,1)
-    assert_equal Time.utc(2006,10,29,1), twz.time
-    assert_equal Time.utc(2006,10,29,5), twz.utc
+    zone = ActiveSupport::TimeZone["Eastern Time (US & Canada)"]
+    twz = zone.local(2006, 10, 29, 1)
+    assert_equal Time.utc(2006, 10, 29, 1), twz.time
+    assert_equal Time.utc(2006, 10, 29, 5), twz.utc
     assert_equal true, twz.dst?
-    assert_equal 'EDT', twz.zone
+    assert_equal "EDT", twz.zone
+  end
+
+  def test_local_with_ambiguous_time
+    zone = ActiveSupport::TimeZone["Moscow"]
+    assert_equal Time.utc(2014, 10, 25, 22, 0, 0), zone.local(2014, 10, 26, 1, 0, 0)
   end
 
   def test_at
-    zone = ActiveSupport::TimeZone['Eastern Time (US & Canada)']
+    zone = ActiveSupport::TimeZone["Eastern Time (US & Canada)"]
     secs = 946684800.0
     twz = zone.at(secs)
-    assert_equal Time.utc(1999,12,31,19), twz.time
+    assert_equal Time.utc(1999, 12, 31, 19), twz.time
     assert_equal Time.utc(2000), twz.utc
     assert_equal zone, twz.time_zone
     assert_equal secs, twz.to_f
   end
 
   def test_at_with_old_date
-    zone = ActiveSupport::TimeZone['Eastern Time (US & Canada)']
+    zone = ActiveSupport::TimeZone["Eastern Time (US & Canada)"]
     secs = DateTime.civil(1850).to_f
     twz = zone.at(secs)
     assert_equal [1850, 1, 1, 0], [twz.utc.year, twz.utc.mon, twz.utc.day, twz.utc.hour]
@@ -215,10 +225,104 @@ class TimeZoneTest < ActiveSupport::TestCase
     assert_equal secs, twz.to_f
   end
 
+  def test_iso8601
+    zone = ActiveSupport::TimeZone["Eastern Time (US & Canada)"]
+    twz = zone.iso8601("1999-12-31T19:00:00")
+    assert_equal Time.utc(1999, 12, 31, 19), twz.time
+    assert_equal Time.utc(2000), twz.utc
+    assert_equal zone, twz.time_zone
+  end
+
+  def test_iso8601_with_fractional_seconds
+    zone = ActiveSupport::TimeZone["Eastern Time (US & Canada)"]
+    twz = zone.iso8601("1999-12-31T19:00:00.750")
+    assert_equal 750000, twz.time.usec
+    assert_equal Time.utc(1999, 12, 31, 19, 0, 0 + Rational(3, 4)), twz.time
+    assert_equal Time.utc(2000, 1, 1, 0, 0, 0 + Rational(3, 4)), twz.utc
+    assert_equal zone, twz.time_zone
+  end
+
+  def test_iso8601_with_zone
+    zone = ActiveSupport::TimeZone["Eastern Time (US & Canada)"]
+    twz = zone.iso8601("1999-12-31T14:00:00-10:00")
+    assert_equal Time.utc(1999, 12, 31, 19), twz.time
+    assert_equal Time.utc(2000), twz.utc
+    assert_equal zone, twz.time_zone
+  end
+
+  def test_iso8601_with_invalid_string
+    zone = ActiveSupport::TimeZone["Eastern Time (US & Canada)"]
+
+    exception = assert_raises(ArgumentError) do
+      zone.iso8601("foobar")
+    end
+
+    assert_equal "invalid date", exception.message
+  end
+
+  def test_iso8601_with_missing_time_components
+    zone = ActiveSupport::TimeZone["Eastern Time (US & Canada)"]
+    twz = zone.iso8601("1999-12-31")
+    assert_equal Time.utc(1999, 12, 31, 0, 0, 0), twz.time
+    assert_equal Time.utc(1999, 12, 31, 5, 0, 0), twz.utc
+    assert_equal zone, twz.time_zone
+  end
+
+  def test_iso8601_with_old_date
+    zone = ActiveSupport::TimeZone["Eastern Time (US & Canada)"]
+    twz = zone.iso8601("1883-12-31T19:00:00")
+    assert_equal [0, 0, 19, 31, 12, 1883], twz.to_a[0, 6]
+    assert_equal zone, twz.time_zone
+  end
+
+  def test_iso8601_far_future_date_with_time_zone_offset_in_string
+    zone = ActiveSupport::TimeZone["Eastern Time (US & Canada)"]
+    twz = zone.iso8601("2050-12-31T19:00:00-10:00") # i.e., 2050-01-01 05:00:00 UTC
+    assert_equal [0, 0, 0, 1, 1, 2051], twz.to_a[0, 6]
+    assert_equal zone, twz.time_zone
+  end
+
+  def test_iso8601_should_not_black_out_system_timezone_dst_jump
+    with_env_tz("EET") do
+      zone = ActiveSupport::TimeZone["Pacific Time (US & Canada)"]
+      twz = zone.iso8601("2012-03-25T03:29:00")
+      assert_equal [0, 29, 3, 25, 3, 2012], twz.to_a[0, 6]
+    end
+  end
+
+  def test_iso8601_should_black_out_app_timezone_dst_jump
+    with_env_tz("EET") do
+      zone = ActiveSupport::TimeZone["Pacific Time (US & Canada)"]
+      twz = zone.iso8601("2012-03-11T02:29:00")
+      assert_equal [0, 29, 3, 11, 3, 2012], twz.to_a[0, 6]
+    end
+  end
+
+  def test_iso8601_doesnt_use_local_dst
+    with_env_tz "US/Eastern" do
+      zone = ActiveSupport::TimeZone["UTC"]
+      twz = zone.iso8601("2013-03-10T02:00:00")
+      assert_equal Time.utc(2013, 3, 10, 2, 0, 0), twz.time
+    end
+  end
+
+  def test_iso8601_handles_dst_jump
+    with_env_tz "US/Eastern" do
+      zone = ActiveSupport::TimeZone["Eastern Time (US & Canada)"]
+      twz = zone.iso8601("2013-03-10T02:00:00")
+      assert_equal Time.utc(2013, 3, 10, 3, 0, 0), twz.time
+    end
+  end
+
+  def test_iso8601_with_ambiguous_time
+    zone = ActiveSupport::TimeZone["Moscow"]
+    assert_equal Time.utc(2014, 10, 25, 22, 0, 0), zone.parse("2014-10-26T01:00:00")
+  end
+
   def test_parse
-    zone = ActiveSupport::TimeZone['Eastern Time (US & Canada)']
-    twz = zone.parse('1999-12-31 19:00:00')
-    assert_equal Time.utc(1999,12,31,19), twz.time
+    zone = ActiveSupport::TimeZone["Eastern Time (US & Canada)"]
+    twz = zone.parse("1999-12-31 19:00:00")
+    assert_equal Time.utc(1999, 12, 31, 19), twz.time
     assert_equal Time.utc(2000), twz.utc
     assert_equal zone, twz.time_zone
   end
@@ -226,183 +330,321 @@ class TimeZoneTest < ActiveSupport::TestCase
   def test_parse_string_with_timezone
     (-11..13).each do |timezone_offset|
       zone = ActiveSupport::TimeZone[timezone_offset]
-      twz = zone.parse('1999-12-31 19:00:00')
+      twz = zone.parse("1999-12-31 19:00:00")
       assert_equal twz, zone.parse(twz.to_s)
     end
   end
 
   def test_parse_with_old_date
-    zone = ActiveSupport::TimeZone['Eastern Time (US & Canada)']
-    twz = zone.parse('1883-12-31 19:00:00')
-    assert_equal [0,0,19,31,12,1883], twz.to_a[0,6]
+    zone = ActiveSupport::TimeZone["Eastern Time (US & Canada)"]
+    twz = zone.parse("1883-12-31 19:00:00")
+    assert_equal [0, 0, 19, 31, 12, 1883], twz.to_a[0, 6]
     assert_equal zone, twz.time_zone
   end
 
   def test_parse_far_future_date_with_time_zone_offset_in_string
-    zone = ActiveSupport::TimeZone['Eastern Time (US & Canada)']
-    twz = zone.parse('2050-12-31 19:00:00 -10:00') # i.e., 2050-01-01 05:00:00 UTC
-    assert_equal [0,0,0,1,1,2051], twz.to_a[0,6]
+    zone = ActiveSupport::TimeZone["Eastern Time (US & Canada)"]
+    twz = zone.parse("2050-12-31 19:00:00 -10:00") # i.e., 2050-01-01 05:00:00 UTC
+    assert_equal [0, 0, 0, 1, 1, 2051], twz.to_a[0, 6]
     assert_equal zone, twz.time_zone
   end
 
   def test_parse_returns_nil_when_string_without_date_information_is_passed_in
-    zone = ActiveSupport::TimeZone['Eastern Time (US & Canada)']
-    assert_nil zone.parse('foobar')
-    assert_nil zone.parse('   ')
+    zone = ActiveSupport::TimeZone["Eastern Time (US & Canada)"]
+    assert_nil zone.parse("foobar")
+    assert_nil zone.parse("   ")
   end
 
   def test_parse_with_incomplete_date
-    zone = ActiveSupport::TimeZone['Eastern Time (US & Canada)']
-    zone.stub(:now, zone.local(1999,12,31)) do
-      twz = zone.parse('19:00:00')
-      assert_equal Time.utc(1999,12,31,19), twz.time
+    zone = ActiveSupport::TimeZone["Eastern Time (US & Canada)"]
+    zone.stub(:now, zone.local(1999, 12, 31)) do
+      twz = zone.parse("19:00:00")
+      assert_equal Time.utc(1999, 12, 31, 19), twz.time
     end
   end
 
   def test_parse_with_day_omitted
-    with_env_tz 'US/Eastern' do
-      zone = ActiveSupport::TimeZone['Eastern Time (US & Canada)']
-      assert_equal Time.local(2000, 2, 1), zone.parse('Feb', Time.local(2000, 1, 1))
-      assert_equal Time.local(2005, 2, 1), zone.parse('Feb 2005', Time.local(2000, 1, 1))
-      assert_equal Time.local(2005, 2, 2), zone.parse('2 Feb 2005', Time.local(2000, 1, 1))
+    with_env_tz "US/Eastern" do
+      zone = ActiveSupport::TimeZone["Eastern Time (US & Canada)"]
+      assert_equal Time.local(2000, 2, 1), zone.parse("Feb", Time.local(2000, 1, 1))
+      assert_equal Time.local(2005, 2, 1), zone.parse("Feb 2005", Time.local(2000, 1, 1))
+      assert_equal Time.local(2005, 2, 2), zone.parse("2 Feb 2005", Time.local(2000, 1, 1))
     end
   end
 
   def test_parse_should_not_black_out_system_timezone_dst_jump
-    with_env_tz('EET') do
-      zone = ActiveSupport::TimeZone['Pacific Time (US & Canada)']
-      twz = zone.parse('2012-03-25 03:29:00')
-      assert_equal [0, 29, 3, 25, 3, 2012], twz.to_a[0,6]
+    with_env_tz("EET") do
+      zone = ActiveSupport::TimeZone["Pacific Time (US & Canada)"]
+      twz = zone.parse("2012-03-25 03:29:00")
+      assert_equal [0, 29, 3, 25, 3, 2012], twz.to_a[0, 6]
     end
   end
 
   def test_parse_should_black_out_app_timezone_dst_jump
-    with_env_tz('EET') do
-      zone = ActiveSupport::TimeZone['Pacific Time (US & Canada)']
-      twz = zone.parse('2012-03-11 02:29:00')
-      assert_equal [0, 29, 3, 11, 3, 2012], twz.to_a[0,6]
+    with_env_tz("EET") do
+      zone = ActiveSupport::TimeZone["Pacific Time (US & Canada)"]
+      twz = zone.parse("2012-03-11 02:29:00")
+      assert_equal [0, 29, 3, 11, 3, 2012], twz.to_a[0, 6]
     end
   end
 
   def test_parse_with_missing_time_components
-    zone = ActiveSupport::TimeZone['Eastern Time (US & Canada)']
+    zone = ActiveSupport::TimeZone["Eastern Time (US & Canada)"]
     zone.stub(:now, zone.local(1999, 12, 31, 12, 59, 59)) do
-      twz = zone.parse('2012-12-01')
+      twz = zone.parse("2012-12-01")
       assert_equal Time.utc(2012, 12, 1), twz.time
     end
   end
 
   def test_parse_with_javascript_date
-    zone = ActiveSupport::TimeZone['Eastern Time (US & Canada)']
+    zone = ActiveSupport::TimeZone["Eastern Time (US & Canada)"]
     twz = zone.parse("Mon May 28 2012 00:00:00 GMT-0700 (PDT)")
     assert_equal Time.utc(2012, 5, 28, 7, 0, 0), twz.utc
   end
 
   def test_parse_doesnt_use_local_dst
-    with_env_tz 'US/Eastern' do
-      zone = ActiveSupport::TimeZone['UTC']
-      twz = zone.parse('2013-03-10 02:00:00')
+    with_env_tz "US/Eastern" do
+      zone = ActiveSupport::TimeZone["UTC"]
+      twz = zone.parse("2013-03-10 02:00:00")
       assert_equal Time.utc(2013, 3, 10, 2, 0, 0), twz.time
     end
   end
 
   def test_parse_handles_dst_jump
-    with_env_tz 'US/Eastern' do
-      zone = ActiveSupport::TimeZone['Eastern Time (US & Canada)']
-      twz = zone.parse('2013-03-10 02:00:00')
+    with_env_tz "US/Eastern" do
+      zone = ActiveSupport::TimeZone["Eastern Time (US & Canada)"]
+      twz = zone.parse("2013-03-10 02:00:00")
+      assert_equal Time.utc(2013, 3, 10, 3, 0, 0), twz.time
+    end
+  end
+
+  def test_parse_with_invalid_date
+    zone = ActiveSupport::TimeZone["UTC"]
+
+    exception = assert_raises(ArgumentError) do
+      zone.parse("9000")
+    end
+
+    assert_equal "argument out of range", exception.message
+  end
+
+  def test_parse_with_ambiguous_time
+    zone = ActiveSupport::TimeZone["Moscow"]
+    assert_equal Time.utc(2014, 10, 25, 22, 0, 0), zone.parse("2014-10-26 01:00:00")
+  end
+
+  def test_rfc3339
+    zone = ActiveSupport::TimeZone["Eastern Time (US & Canada)"]
+    twz = zone.rfc3339("1999-12-31T14:00:00-10:00")
+    assert_equal Time.utc(1999, 12, 31, 19), twz.time
+    assert_equal Time.utc(2000), twz.utc
+    assert_equal zone, twz.time_zone
+  end
+
+  def test_rfc3339_with_fractional_seconds
+    zone = ActiveSupport::TimeZone["Eastern Time (US & Canada)"]
+    twz = zone.iso8601("1999-12-31T14:00:00.750-10:00")
+    assert_equal 750000, twz.time.usec
+    assert_equal Time.utc(1999, 12, 31, 19, 0, 0 + Rational(3, 4)), twz.time
+    assert_equal Time.utc(2000, 1, 1, 0, 0, 0 + Rational(3, 4)), twz.utc
+    assert_equal zone, twz.time_zone
+  end
+
+  def test_rfc3339_with_missing_time
+    zone = ActiveSupport::TimeZone["Eastern Time (US & Canada)"]
+
+    exception = assert_raises(ArgumentError) do
+      zone.rfc3339("1999-12-31")
+    end
+
+    assert_equal "invalid date", exception.message
+  end
+
+  def test_rfc3339_with_missing_offset
+    zone = ActiveSupport::TimeZone["Eastern Time (US & Canada)"]
+
+    exception = assert_raises(ArgumentError) do
+      zone.rfc3339("1999-12-31T19:00:00")
+    end
+
+    assert_equal "invalid date", exception.message
+  end
+
+  def test_rfc3339_with_invalid_string
+    zone = ActiveSupport::TimeZone["Eastern Time (US & Canada)"]
+
+    exception = assert_raises(ArgumentError) do
+      zone.rfc3339("foobar")
+    end
+
+    assert_equal "invalid date", exception.message
+  end
+
+  def test_rfc3339_with_old_date
+    zone = ActiveSupport::TimeZone["Eastern Time (US & Canada)"]
+    twz = zone.rfc3339("1883-12-31T19:00:00-05:00")
+    assert_equal [0, 0, 19, 31, 12, 1883], twz.to_a[0, 6]
+    assert_equal zone, twz.time_zone
+  end
+
+  def test_rfc3339_far_future_date_with_time_zone_offset_in_string
+    zone = ActiveSupport::TimeZone["Eastern Time (US & Canada)"]
+    twz = zone.rfc3339("2050-12-31T19:00:00-10:00") # i.e., 2050-01-01 05:00:00 UTC
+    assert_equal [0, 0, 0, 1, 1, 2051], twz.to_a[0, 6]
+    assert_equal zone, twz.time_zone
+  end
+
+  def test_rfc3339_should_not_black_out_system_timezone_dst_jump
+    with_env_tz("EET") do
+      zone = ActiveSupport::TimeZone["Pacific Time (US & Canada)"]
+      twz = zone.rfc3339("2012-03-25T03:29:00-07:00")
+      assert_equal [0, 29, 3, 25, 3, 2012], twz.to_a[0, 6]
+    end
+  end
+
+  def test_rfc3339_should_black_out_app_timezone_dst_jump
+    with_env_tz("EET") do
+      zone = ActiveSupport::TimeZone["Pacific Time (US & Canada)"]
+      twz = zone.rfc3339("2012-03-11T02:29:00-08:00")
+      assert_equal [0, 29, 3, 11, 3, 2012], twz.to_a[0, 6]
+    end
+  end
+
+  def test_rfc3339_doesnt_use_local_dst
+    with_env_tz "US/Eastern" do
+      zone = ActiveSupport::TimeZone["UTC"]
+      twz = zone.rfc3339("2013-03-10T02:00:00Z")
+      assert_equal Time.utc(2013, 3, 10, 2, 0, 0), twz.time
+    end
+  end
+
+  def test_rfc3339_handles_dst_jump
+    with_env_tz "US/Eastern" do
+      zone = ActiveSupport::TimeZone["Eastern Time (US & Canada)"]
+      twz = zone.iso8601("2013-03-10T02:00:00-05:00")
       assert_equal Time.utc(2013, 3, 10, 3, 0, 0), twz.time
     end
   end
 
   def test_strptime
-    zone = ActiveSupport::TimeZone['Eastern Time (US & Canada)']
-    twz = zone.strptime('1999-12-31 12:00:00', '%Y-%m-%d %H:%M:%S')
-    assert_equal Time.utc(1999,12,31,17), twz
-    assert_equal Time.utc(1999,12,31,12), twz.time
-    assert_equal Time.utc(1999,12,31,17), twz.utc
+    zone = ActiveSupport::TimeZone["Eastern Time (US & Canada)"]
+    twz = zone.strptime("1999-12-31 12:00:00", "%Y-%m-%d %H:%M:%S")
+    assert_equal Time.utc(1999, 12, 31, 17), twz
+    assert_equal Time.utc(1999, 12, 31, 12), twz.time
+    assert_equal Time.utc(1999, 12, 31, 17), twz.utc
     assert_equal zone, twz.time_zone
   end
 
   def test_strptime_with_nondefault_time_zone
-    with_tz_default ActiveSupport::TimeZone['Pacific Time (US & Canada)'] do
-      zone = ActiveSupport::TimeZone['Eastern Time (US & Canada)']
-      twz = zone.strptime('1999-12-31 12:00:00', '%Y-%m-%d %H:%M:%S')
-      assert_equal Time.utc(1999,12,31,17), twz
-      assert_equal Time.utc(1999,12,31,12), twz.time
-      assert_equal Time.utc(1999,12,31,17), twz.utc
+    with_tz_default ActiveSupport::TimeZone["Pacific Time (US & Canada)"] do
+      zone = ActiveSupport::TimeZone["Eastern Time (US & Canada)"]
+      twz = zone.strptime("1999-12-31 12:00:00", "%Y-%m-%d %H:%M:%S")
+      assert_equal Time.utc(1999, 12, 31, 17), twz
+      assert_equal Time.utc(1999, 12, 31, 12), twz.time
+      assert_equal Time.utc(1999, 12, 31, 17), twz.utc
       assert_equal zone, twz.time_zone
     end
   end
 
   def test_strptime_with_explicit_time_zone_as_abbrev
-    zone = ActiveSupport::TimeZone['Eastern Time (US & Canada)']
-    twz = zone.strptime('1999-12-31 12:00:00 PST', '%Y-%m-%d %H:%M:%S %Z')
-    assert_equal Time.utc(1999,12,31,20), twz
-    assert_equal Time.utc(1999,12,31,15), twz.time
-    assert_equal Time.utc(1999,12,31,20), twz.utc
+    zone = ActiveSupport::TimeZone["Eastern Time (US & Canada)"]
+    twz = zone.strptime("1999-12-31 12:00:00 PST", "%Y-%m-%d %H:%M:%S %Z")
+    assert_equal Time.utc(1999, 12, 31, 20), twz
+    assert_equal Time.utc(1999, 12, 31, 15), twz.time
+    assert_equal Time.utc(1999, 12, 31, 20), twz.utc
     assert_equal zone, twz.time_zone
   end
 
   def test_strptime_with_explicit_time_zone_as_h_offset
-    zone = ActiveSupport::TimeZone['Eastern Time (US & Canada)']
-    twz = zone.strptime('1999-12-31 12:00:00 -08', '%Y-%m-%d %H:%M:%S %:::z')
-    assert_equal Time.utc(1999,12,31,20), twz
-    assert_equal Time.utc(1999,12,31,15), twz.time
-    assert_equal Time.utc(1999,12,31,20), twz.utc
+    zone = ActiveSupport::TimeZone["Eastern Time (US & Canada)"]
+    twz = zone.strptime("1999-12-31 12:00:00 -08", "%Y-%m-%d %H:%M:%S %:::z")
+    assert_equal Time.utc(1999, 12, 31, 20), twz
+    assert_equal Time.utc(1999, 12, 31, 15), twz.time
+    assert_equal Time.utc(1999, 12, 31, 20), twz.utc
     assert_equal zone, twz.time_zone
   end
 
   def test_strptime_with_explicit_time_zone_as_hm_offset
-    zone = ActiveSupport::TimeZone['Eastern Time (US & Canada)']
-    twz = zone.strptime('1999-12-31 12:00:00 -08:00', '%Y-%m-%d %H:%M:%S %:z')
-    assert_equal Time.utc(1999,12,31,20), twz
-    assert_equal Time.utc(1999,12,31,15), twz.time
-    assert_equal Time.utc(1999,12,31,20), twz.utc
+    zone = ActiveSupport::TimeZone["Eastern Time (US & Canada)"]
+    twz = zone.strptime("1999-12-31 12:00:00 -08:00", "%Y-%m-%d %H:%M:%S %:z")
+    assert_equal Time.utc(1999, 12, 31, 20), twz
+    assert_equal Time.utc(1999, 12, 31, 15), twz.time
+    assert_equal Time.utc(1999, 12, 31, 20), twz.utc
     assert_equal zone, twz.time_zone
   end
 
   def test_strptime_with_explicit_time_zone_as_hms_offset
-    zone = ActiveSupport::TimeZone['Eastern Time (US & Canada)']
-    twz = zone.strptime('1999-12-31 12:00:00 -08:00:00', '%Y-%m-%d %H:%M:%S %::z')
-    assert_equal Time.utc(1999,12,31,20), twz
-    assert_equal Time.utc(1999,12,31,15), twz.time
-    assert_equal Time.utc(1999,12,31,20), twz.utc
+    zone = ActiveSupport::TimeZone["Eastern Time (US & Canada)"]
+    twz = zone.strptime("1999-12-31 12:00:00 -08:00:00", "%Y-%m-%d %H:%M:%S %::z")
+    assert_equal Time.utc(1999, 12, 31, 20), twz
+    assert_equal Time.utc(1999, 12, 31, 15), twz.time
+    assert_equal Time.utc(1999, 12, 31, 20), twz.utc
     assert_equal zone, twz.time_zone
   end
 
   def test_strptime_with_almost_explicit_time_zone
-    zone = ActiveSupport::TimeZone['Eastern Time (US & Canada)']
-    twz = zone.strptime('1999-12-31 12:00:00 %Z', '%Y-%m-%d %H:%M:%S %%Z')
-    assert_equal Time.utc(1999,12,31,17), twz
-    assert_equal Time.utc(1999,12,31,12), twz.time
-    assert_equal Time.utc(1999,12,31,17), twz.utc
+    zone = ActiveSupport::TimeZone["Eastern Time (US & Canada)"]
+    twz = zone.strptime("1999-12-31 12:00:00 %Z", "%Y-%m-%d %H:%M:%S %%Z")
+    assert_equal Time.utc(1999, 12, 31, 17), twz
+    assert_equal Time.utc(1999, 12, 31, 12), twz.time
+    assert_equal Time.utc(1999, 12, 31, 17), twz.utc
     assert_equal zone, twz.time_zone
   end
 
   def test_strptime_with_day_omitted
-    with_env_tz 'US/Eastern' do
-      zone = ActiveSupport::TimeZone['Eastern Time (US & Canada)']
-      assert_equal Time.local(2000, 2, 1), zone.strptime('Feb', '%b', Time.local(2000, 1, 1))
-      assert_equal Time.local(2005, 2, 1), zone.strptime('Feb 2005', '%b %Y', Time.local(2000, 1, 1))
-      assert_equal Time.local(2005, 2, 2), zone.strptime('2 Feb 2005', '%e %b %Y', Time.local(2000, 1, 1))
+    with_env_tz "US/Eastern" do
+      zone = ActiveSupport::TimeZone["Eastern Time (US & Canada)"]
+      assert_equal Time.local(2000, 2, 1), zone.strptime("Feb", "%b", Time.local(2000, 1, 1))
+      assert_equal Time.local(2005, 2, 1), zone.strptime("Feb 2005", "%b %Y", Time.local(2000, 1, 1))
+      assert_equal Time.local(2005, 2, 2), zone.strptime("2 Feb 2005", "%e %b %Y", Time.local(2000, 1, 1))
     end
   end
 
+  def test_strptime_with_malformed_string
+    with_env_tz "US/Eastern" do
+      zone = ActiveSupport::TimeZone["Eastern Time (US & Canada)"]
+      assert_raise(ArgumentError) { zone.strptime("1999-12-31", "%Y/%m/%d") }
+    end
+  end
+
+  def test_strptime_with_timestamp_seconds
+    with_env_tz "US/Eastern" do
+      zone = ActiveSupport::TimeZone["Eastern Time (US & Canada)"]
+      time_str = "1470272280"
+      time = zone.strptime(time_str, "%s")
+      assert_equal Time.at(1470272280), time
+    end
+  end
+
+  def test_strptime_with_timestamp_milliseconds
+    with_env_tz "US/Eastern" do
+      zone = ActiveSupport::TimeZone["Eastern Time (US & Canada)"]
+      time_str = "1470272280000"
+      time = zone.strptime(time_str, "%Q")
+      assert_equal Time.at(1470272280), time
+    end
+  end
+
+  def test_strptime_with_ambiguous_time
+    zone = ActiveSupport::TimeZone["Moscow"]
+    assert_equal Time.utc(2014, 10, 25, 22, 0, 0), zone.strptime("2014-10-26 01:00:00", "%Y-%m-%d %H:%M:%S")
+  end
+
   def test_utc_offset_lazy_loaded_from_tzinfo_when_not_passed_in_to_initialize
-    tzinfo = TZInfo::Timezone.get('America/New_York')
+    tzinfo = TZInfo::Timezone.get("America/New_York")
     zone = ActiveSupport::TimeZone.create(tzinfo.name, nil, tzinfo)
-    assert_equal nil, zone.instance_variable_get('@utc_offset')
+    assert_nil zone.instance_variable_get("@utc_offset")
     assert_equal(-18_000, zone.utc_offset)
   end
 
   def test_utc_offset_is_not_cached_when_current_period_gets_stale
-    tz = ActiveSupport::TimeZone.create('Moscow')
+    tz = ActiveSupport::TimeZone.create("Moscow")
     travel_to(Time.utc(2014, 10, 25, 21)) do # 1 hour before TZ change
-      assert_equal 14400, tz.utc_offset, 'utc_offset should be initialized according to current_period'
+      assert_equal 14400, tz.utc_offset, "utc_offset should be initialized according to current_period"
     end
 
     travel_to(Time.utc(2014, 10, 25, 22)) do # after TZ change
-      assert_equal 10800, tz.utc_offset, 'utc_offset should not be cached when current_period gets stale'
+      assert_equal 10800, tz.utc_offset, "utc_offset should not be cached when current_period gets stale"
     end
   end
 
@@ -425,57 +667,64 @@ class TimeZoneTest < ActiveSupport::TestCase
   end
 
   def test_formatted_offset_positive
-    zone = ActiveSupport::TimeZone['New Delhi']
+    zone = ActiveSupport::TimeZone["New Delhi"]
     assert_equal "+05:30", zone.formatted_offset
     assert_equal "+0530", zone.formatted_offset(false)
   end
 
   def test_formatted_offset_negative
-    zone = ActiveSupport::TimeZone['Eastern Time (US & Canada)']
+    zone = ActiveSupport::TimeZone["Eastern Time (US & Canada)"]
     assert_equal "-05:00", zone.formatted_offset
     assert_equal "-0500", zone.formatted_offset(false)
   end
 
   def test_z_format_strings
-    zone = ActiveSupport::TimeZone['Tokyo']
+    zone = ActiveSupport::TimeZone["Tokyo"]
     twz = zone.now
-    assert_equal '+0900',     twz.strftime('%z')
-    assert_equal '+09:00',    twz.strftime('%:z')
-    assert_equal '+09:00:00', twz.strftime('%::z')
+    assert_equal "+0900",     twz.strftime("%z")
+    assert_equal "+09:00",    twz.strftime("%:z")
+    assert_equal "+09:00:00", twz.strftime("%::z")
   end
 
   def test_formatted_offset_zero
-    zone = ActiveSupport::TimeZone['London']
+    zone = ActiveSupport::TimeZone["London"]
     assert_equal "+00:00", zone.formatted_offset
-    assert_equal "UTC", zone.formatted_offset(true, 'UTC')
+    assert_equal "UTC", zone.formatted_offset(true, "UTC")
   end
 
   def test_zone_compare
-    zone1 = ActiveSupport::TimeZone['Central Time (US & Canada)'] # offset -0600
-    zone2 = ActiveSupport::TimeZone['Eastern Time (US & Canada)'] # offset -0500
+    zone1 = ActiveSupport::TimeZone["Central Time (US & Canada)"] # offset -0600
+    zone2 = ActiveSupport::TimeZone["Eastern Time (US & Canada)"] # offset -0500
     assert zone1 < zone2
     assert zone2 > zone1
     assert zone1 == zone1
   end
 
   def test_zone_match
-    zone = ActiveSupport::TimeZone['Eastern Time (US & Canada)']
+    zone = ActiveSupport::TimeZone["Eastern Time (US & Canada)"]
     assert zone =~ /Eastern/
     assert zone =~ /New_York/
     assert zone !~ /Nonexistent_Place/
   end
 
   def test_to_s
-    assert_equal "(GMT+05:30) New Delhi", ActiveSupport::TimeZone['New Delhi'].to_s
+    assert_equal "(GMT+05:30) New Delhi", ActiveSupport::TimeZone["New Delhi"].to_s
   end
 
   def test_all_sorted
     all = ActiveSupport::TimeZone.all
-    1.upto( all.length-1 ) do |i|
-      assert all[i-1] < all[i]
+    1.upto(all.length - 1) do |i|
+      assert all[i - 1] < all[i]
     end
   end
 
+  def test_all_uninfluenced_by_time_zone_lookups_delegated_to_tzinfo
+    ActiveSupport::TimeZone.clear
+    galapagos = ActiveSupport::TimeZone["Pacific/Galapagos"]
+    all_zones = ActiveSupport::TimeZone.all
+    assert_not_includes all_zones, galapagos
+  end
+
   def test_index
     assert_nil ActiveSupport::TimeZone["bogus"]
     assert_instance_of ActiveSupport::TimeZone, ActiveSupport::TimeZone["Central Time (US & Canada)"]
@@ -498,13 +747,17 @@ class TimeZoneTest < ActiveSupport::TestCase
   end
 
   def test_us_zones
-    assert ActiveSupport::TimeZone.us_zones.include?(ActiveSupport::TimeZone["Hawaii"])
-    assert !ActiveSupport::TimeZone.us_zones.include?(ActiveSupport::TimeZone["Kuala Lumpur"])
+    assert_includes ActiveSupport::TimeZone.us_zones, ActiveSupport::TimeZone["Hawaii"]
+    assert_not_includes ActiveSupport::TimeZone.us_zones, ActiveSupport::TimeZone["Kuala Lumpur"]
   end
 
   def test_country_zones
-    assert ActiveSupport::TimeZone.country_zones("ru").include?(ActiveSupport::TimeZone["Moscow"])
-    assert !ActiveSupport::TimeZone.country_zones(:ru).include?(ActiveSupport::TimeZone["Kuala Lumpur"])
+    assert_includes ActiveSupport::TimeZone.country_zones("ru"), ActiveSupport::TimeZone["Moscow"]
+    assert_not_includes ActiveSupport::TimeZone.country_zones(:ru), ActiveSupport::TimeZone["Kuala Lumpur"]
+  end
+
+  def test_country_zones_without_mappings
+    assert_includes ActiveSupport::TimeZone.country_zones(:sv), ActiveSupport::TimeZone["America/El_Salvador"]
   end
 
   def test_to_yaml
diff --git a/activesupport/test/time_zone_test_helpers.rb b/activesupport/test/time_zone_test_helpers.rb
index eb6f7d0f85..051703a781 100644
--- a/activesupport/test/time_zone_test_helpers.rb
+++ b/activesupport/test/time_zone_test_helpers.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module TimeZoneTestHelpers
   def with_tz_default(tz = nil)
     old_tz = Time.zone
@@ -7,11 +9,11 @@ module TimeZoneTestHelpers
     Time.zone = old_tz
   end
 
-  def with_env_tz(new_tz = 'US/Eastern')
-    old_tz, ENV['TZ'] = ENV['TZ'], new_tz
+  def with_env_tz(new_tz = "US/Eastern")
+    old_tz, ENV["TZ"] = ENV["TZ"], new_tz
     yield
   ensure
-    old_tz ? ENV['TZ'] = old_tz : ENV.delete('TZ')
+    old_tz ? ENV["TZ"] = old_tz : ENV.delete("TZ")
   end
 
   def with_preserve_timezone(value)
diff --git a/activesupport/test/transliterate_test.rb b/activesupport/test/transliterate_test.rb
index 378421fedd..7d19447598 100644
--- a/activesupport/test/transliterate_test.rb
+++ b/activesupport/test/transliterate_test.rb
@@ -1,5 +1,7 @@
-require 'abstract_unit'
-require 'active_support/inflector/transliterate'
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "active_support/inflector/transliterate"
 
 class TransliterateTest < ActiveSupport::TestCase
   def test_transliterate_should_not_change_ascii_chars
@@ -13,7 +15,7 @@ class TransliterateTest < ActiveSupport::TestCase
     # create string with range of Unicode's western characters with
     # diacritics, excluding the division and multiplication signs which for
     # some reason or other are floating in the middle of all the letters.
-    string = (0xC0..0x17E).to_a.reject {|c| [0xD7, 0xF7].include?(c)}.pack("U*")
+    string = (0xC0..0x17E).to_a.reject { |c| [0xD7, 0xF7].include?(c) }.pack("U*")
     string.each_char do |char|
       assert_match %r{^[a-zA-Z']*$}, ActiveSupport::Inflector.transliterate(char)
     end
@@ -21,7 +23,7 @@ class TransliterateTest < ActiveSupport::TestCase
 
   def test_transliterate_should_work_with_custom_i18n_rules_and_uncomposed_utf8
     char = [117, 776].pack("U*") # "ü" as ASCII "u" plus COMBINING DIAERESIS
-    I18n.backend.store_translations(:de, :i18n => {:transliterate => {:rule => {"ü" => "ue"}}})
+    I18n.backend.store_translations(:de, i18n: { transliterate: { rule: { "ü" => "ue" } } })
     default_locale, I18n.locale = I18n.locale, :de
     assert_equal "ue", ActiveSupport::Inflector.transliterate(char)
   ensure
@@ -31,4 +33,22 @@ class TransliterateTest < ActiveSupport::TestCase
   def test_transliterate_should_allow_a_custom_replacement_char
     assert_equal "a*b", ActiveSupport::Inflector.transliterate("a索b", "*")
   end
+
+  def test_transliterate_handles_empty_string
+    assert_equal "", ActiveSupport::Inflector.transliterate("")
+  end
+
+  def test_transliterate_handles_nil
+    exception = assert_raises ArgumentError do
+      ActiveSupport::Inflector.transliterate(nil)
+    end
+    assert_equal "Can only transliterate strings. Received NilClass", exception.message
+  end
+
+  def test_transliterate_handles_unknown_object
+    exception = assert_raises ArgumentError do
+      ActiveSupport::Inflector.transliterate(Object.new)
+    end
+    assert_equal "Can only transliterate strings. Received Object", exception.message
+  end
 end
diff --git a/activesupport/test/xml_mini/jdom_engine_test.rb b/activesupport/test/xml_mini/jdom_engine_test.rb
index ed4de8aba2..97a533aafb 100644
--- a/activesupport/test/xml_mini/jdom_engine_test.rb
+++ b/activesupport/test/xml_mini/jdom_engine_test.rb
@@ -1,37 +1,10 @@
-if RUBY_PLATFORM =~ /java/
-  require 'abstract_unit'
-  require 'active_support/xml_mini'
-  require 'active_support/core_ext/hash/conversions'
+# frozen_string_literal: true
 
+require_relative "xml_mini_engine_test"
 
-  class JDOMEngineTest < ActiveSupport::TestCase
-    include ActiveSupport
-
-    FILES_DIR = File.dirname(__FILE__) + '/../fixtures/xml'
-
-    def setup
-      @default_backend = XmlMini.backend
-      XmlMini.backend = 'JDOM'
-    end
-
-    def teardown
-      XmlMini.backend = @default_backend
-    end
-
-    def test_file_from_xml
-       hash = Hash.from_xml(<<-eoxml)
-         <blog>
-           <logo type="file" name="logo.png" content_type="image/png">
-           </logo>
-         </blog>
-       eoxml
-       assert hash.has_key?('blog')
-       assert hash['blog'].has_key?('logo')
-
-       file = hash['blog']['logo']
-       assert_equal 'logo.png', file.original_filename
-       assert_equal 'image/png', file.content_type
-    end
+XMLMiniEngineTest.run_with_platform("java") do
+  class JDOMEngineTest < XMLMiniEngineTest
+    FILES_DIR = File.expand_path("../fixtures/xml", __dir__)
 
     def test_not_allowed_to_expand_entities_to_files
       attack_xml = <<-EOT
@@ -40,7 +13,7 @@ if RUBY_PLATFORM =~ /java/
       ]>
       <member>x&a;</member>
       EOT
-      assert_equal 'x', Hash.from_xml(attack_xml)["member"]
+      assert_equal "x", Hash.from_xml(attack_xml)["member"]
     end
 
     def test_not_allowed_to_expand_parameter_entities_to_files
@@ -52,137 +25,29 @@ if RUBY_PLATFORM =~ /java/
       <member>x&a;</member>
       EOT
       assert_raise Java::OrgXmlSax::SAXParseException do
-        assert_equal 'x', Hash.from_xml(attack_xml)["member"]
+        assert_equal "x", Hash.from_xml(attack_xml)["member"]
       end
     end
 
-
     def test_not_allowed_to_load_external_doctypes
       attack_xml = <<-EOT
       <!DOCTYPE member SYSTEM "file://#{FILES_DIR}/jdom_doctype.dtd">
       <member>x&a;</member>
       EOT
-      assert_equal 'x', Hash.from_xml(attack_xml)["member"]
+      assert_equal "x", Hash.from_xml(attack_xml)["member"]
     end
 
-    def test_exception_thrown_on_expansion_attack
-      assert_raise Java::OrgXmlSax::SAXParseException do
-        attack_xml = <<-EOT
-      <!DOCTYPE member [
-        <!ENTITY a "&b;&b;&b;&b;&b;&b;&b;&b;&b;&b;">
-        <!ENTITY b "&c;&c;&c;&c;&c;&c;&c;&c;&c;&c;">
-        <!ENTITY c "&d;&d;&d;&d;&d;&d;&d;&d;&d;&d;">
-        <!ENTITY d "&e;&e;&e;&e;&e;&e;&e;&e;&e;&e;">
-        <!ENTITY e "&f;&f;&f;&f;&f;&f;&f;&f;&f;&f;">
-        <!ENTITY f "&g;&g;&g;&g;&g;&g;&g;&g;&g;&g;">
-        <!ENTITY g "xxxxxxxxxxxxxxxxxxxxxxxxxxxxxx">
-      ]>
-      <member>
-      &a;
-      </member>
-        EOT
-        Hash.from_xml(attack_xml)
+    private
+      def engine
+        "JDOM"
       end
-    end
-
-    def test_setting_JDOM_as_backend
-      XmlMini.backend = 'JDOM'
-      assert_equal XmlMini_JDOM, XmlMini.backend
-    end
-
-    def test_blank_returns_empty_hash
-      assert_equal({}, XmlMini.parse(nil))
-      assert_equal({}, XmlMini.parse(''))
-    end
-
-    def test_array_type_makes_an_array
-      assert_equal_rexml(<<-eoxml)
-      <blog>
-        <posts type="array">
-          <post>a post</post>
-          <post>another post</post>
-        </posts>
-      </blog>
-      eoxml
-    end
-
-    def test_one_node_document_as_hash
-      assert_equal_rexml(<<-eoxml)
-    <products/>
-      eoxml
-    end
-
-    def test_one_node_with_attributes_document_as_hash
-      assert_equal_rexml(<<-eoxml)
-    <products foo="bar"/>
-      eoxml
-    end
 
-    def test_products_node_with_book_node_as_hash
-      assert_equal_rexml(<<-eoxml)
-    <products>
-      <book name="awesome" id="12345" />
-    </products>
-      eoxml
-    end
-
-    def test_products_node_with_two_book_nodes_as_hash
-      assert_equal_rexml(<<-eoxml)
-    <products>
-      <book name="awesome" id="12345" />
-      <book name="america" id="67890" />
-    </products>
-      eoxml
-    end
-
-    def test_single_node_with_content_as_hash
-      assert_equal_rexml(<<-eoxml)
-      <products>
-        hello world
-      </products>
-      eoxml
-    end
-
-    def test_children_with_children
-      assert_equal_rexml(<<-eoxml)
-    <root>
-      <products>
-        <book name="america" id="67890" />
-      </products>
-    </root>
-      eoxml
-    end
-
-    def test_children_with_text
-      assert_equal_rexml(<<-eoxml)
-    <root>
-      <products>
-        hello everyone
-      </products>
-    </root>
-      eoxml
-    end
-
-    def test_children_with_non_adjacent_text
-      assert_equal_rexml(<<-eoxml)
-    <root>
-      good
-      <products>
-        hello everyone
-      </products>
-      morning
-    </root>
-      eoxml
-    end
+      def expansion_attack_error
+        Java::OrgXmlSax::SAXParseException
+      end
 
-    private
-      def assert_equal_rexml(xml)
-        parsed_xml = XmlMini.parse(xml)
-        hash = XmlMini.with_backend('REXML') { XmlMini.parse(xml) }
-        assert_equal(hash, parsed_xml)
+      def extended_engine?
+        false
       end
   end
-
-else
-  # don't run these test because we aren't running in JRuby
 end
diff --git a/activesupport/test/xml_mini/libxml_engine_test.rb b/activesupport/test/xml_mini/libxml_engine_test.rb
index a8df2e1f7b..3eef3946a3 100644
--- a/activesupport/test/xml_mini/libxml_engine_test.rb
+++ b/activesupport/test/xml_mini/libxml_engine_test.rb
@@ -1,204 +1,21 @@
-begin
-  require 'libxml'
-rescue LoadError
-  # Skip libxml tests
-else
-require 'abstract_unit'
-require 'active_support/xml_mini'
-require 'active_support/core_ext/hash/conversions'
+# frozen_string_literal: true
 
-class LibxmlEngineTest < ActiveSupport::TestCase
-  include ActiveSupport
+require_relative "xml_mini_engine_test"
 
-  def setup
-    @default_backend = XmlMini.backend
-    XmlMini.backend = 'LibXML'
-
-    LibXML::XML::Error.set_handler(&lambda { |error| }) #silence libxml, exceptions will do
-  end
-
-  def teardown
-    XmlMini.backend = @default_backend
-  end
-
-  def test_exception_thrown_on_expansion_attack
-    assert_raise LibXML::XML::Error do
-      attack_xml = %{<?xml version="1.0" encoding="UTF-8"?>
-      <!DOCTYPE member [
-        <!ENTITY a "&b;&b;&b;&b;&b;&b;&b;&b;&b;&b;">
-        <!ENTITY b "&c;&c;&c;&c;&c;&c;&c;&c;&c;&c;">
-        <!ENTITY c "&d;&d;&d;&d;&d;&d;&d;&d;&d;&d;">
-        <!ENTITY d "&e;&e;&e;&e;&e;&e;&e;&e;&e;&e;">
-        <!ENTITY e "&f;&f;&f;&f;&f;&f;&f;&f;&f;&f;">
-        <!ENTITY f "&g;&g;&g;&g;&g;&g;&g;&g;&g;&g;">
-        <!ENTITY g "xxxxxxxxxxxxxxxxxxxxxxxxxxxxxx">
-      ]>
-      <member>
-      &a;
-      </member>
-     }
-      Hash.from_xml(attack_xml)
+XMLMiniEngineTest.run_with_gem("libxml") do
+  class LibxmlEngineTest < XMLMiniEngineTest
+    def setup
+      super
+      LibXML::XML::Error.set_handler(&lambda { |error| }) # silence libxml, exceptions will do
     end
-  end
-
-  def test_setting_libxml_as_backend
-    XmlMini.backend = 'LibXML'
-    assert_equal XmlMini_LibXML, XmlMini.backend
-  end
-
-  def test_blank_returns_empty_hash
-    assert_equal({}, XmlMini.parse(nil))
-    assert_equal({}, XmlMini.parse(''))
-  end
-
-  def test_array_type_makes_an_array
-    assert_equal_rexml(<<-eoxml)
-      <blog>
-        <posts type="array">
-          <post>a post</post>
-          <post>another post</post>
-        </posts>
-      </blog>
-    eoxml
-  end
-
-  def test_one_node_document_as_hash
-    assert_equal_rexml(<<-eoxml)
-    <products/>
-    eoxml
-  end
-
-  def test_one_node_with_attributes_document_as_hash
-    assert_equal_rexml(<<-eoxml)
-    <products foo="bar"/>
-    eoxml
-  end
-
-  def test_products_node_with_book_node_as_hash
-    assert_equal_rexml(<<-eoxml)
-    <products>
-      <book name="awesome" id="12345" />
-    </products>
-    eoxml
-  end
-
-  def test_products_node_with_two_book_nodes_as_hash
-    assert_equal_rexml(<<-eoxml)
-    <products>
-      <book name="awesome" id="12345" />
-      <book name="america" id="67890" />
-    </products>
-    eoxml
-  end
-
-  def test_single_node_with_content_as_hash
-    assert_equal_rexml(<<-eoxml)
-      <products>
-        hello world
-      </products>
-    eoxml
-  end
-
-  def test_children_with_children
-    assert_equal_rexml(<<-eoxml)
-    <root>
-      <products>
-        <book name="america" id="67890" />
-      </products>
-    </root>
-    eoxml
-  end
 
-  def test_children_with_text
-    assert_equal_rexml(<<-eoxml)
-    <root>
-      <products>
-        hello everyone
-      </products>
-    </root>
-    eoxml
-  end
-
-  def test_children_with_non_adjacent_text
-    assert_equal_rexml(<<-eoxml)
-    <root>
-      good
-      <products>
-        hello everyone
-      </products>
-      morning
-    </root>
-    eoxml
-  end
+    private
+      def engine
+        "LibXML"
+      end
 
-  def test_parse_from_io
-    io = StringIO.new(<<-eoxml)
-    <root>
-      good
-      <products>
-        hello everyone
-      </products>
-      morning
-    </root>
-    eoxml
-    assert_equal_rexml(io)
+      def expansion_attack_error
+        LibXML::XML::Error
+      end
   end
-
-  def test_children_with_simple_cdata
-    assert_equal_rexml(<<-eoxml)
-    <root>
-      <products>
-         <![CDATA[cdatablock]]>
-      </products>
-    </root>
-    eoxml
-  end
-
-  def test_children_with_multiple_cdata
-    assert_equal_rexml(<<-eoxml)
-    <root>
-      <products>
-         <![CDATA[cdatablock1]]><![CDATA[cdatablock2]]>
-      </products>
-    </root>
-    eoxml
-  end
-
-  def test_children_with_text_and_cdata
-    assert_equal_rexml(<<-eoxml)
-    <root>
-      <products>
-        hello <![CDATA[cdatablock]]>
-        morning
-      </products>
-    </root>
-    eoxml
-  end
-
-  def test_children_with_blank_text
-    assert_equal_rexml(<<-eoxml)
-    <root>
-      <products>   </products>
-    </root>
-    eoxml
-  end
-
-  def test_children_with_blank_text_and_attribute
-    assert_equal_rexml(<<-eoxml)
-    <root>
-      <products type="file">   </products>
-    </root>
-    eoxml
-  end
-
-
-  private
-    def assert_equal_rexml(xml)
-      parsed_xml = XmlMini.parse(xml)
-      xml.rewind if xml.respond_to?(:rewind)
-      hash = XmlMini.with_backend('REXML') { XmlMini.parse(xml) }
-      assert_equal(hash, parsed_xml)
-    end
-end
-
 end
diff --git a/activesupport/test/xml_mini/libxmlsax_engine_test.rb b/activesupport/test/xml_mini/libxmlsax_engine_test.rb
index d6d90639e2..8e4a30a48e 100644
--- a/activesupport/test/xml_mini/libxmlsax_engine_test.rb
+++ b/activesupport/test/xml_mini/libxmlsax_engine_test.rb
@@ -1,195 +1,16 @@
-begin
-  require 'libxml'
-rescue LoadError
-  # Skip libxml tests
-else
-require 'abstract_unit'
-require 'active_support/xml_mini'
-require 'active_support/core_ext/hash/conversions'
+# frozen_string_literal: true
 
-class LibXMLSAXEngineTest < ActiveSupport::TestCase
-  include ActiveSupport
+require_relative "xml_mini_engine_test"
 
-  def setup
-    @default_backend = XmlMini.backend
-    XmlMini.backend = 'LibXMLSAX'
-  end
-
-  def teardown
-    XmlMini.backend = @default_backend
-  end
-
-  def test_exception_thrown_on_expansion_attack
-    assert_raise LibXML::XML::Error do
-      attack_xml = <<-EOT
-      <?xml version="1.0" encoding="UTF-8"?>
-      <!DOCTYPE member [
-        <!ENTITY a "&b;&b;&b;&b;&b;&b;&b;&b;&b;&b;">
-        <!ENTITY b "&c;&c;&c;&c;&c;&c;&c;&c;&c;&c;">
-        <!ENTITY c "&d;&d;&d;&d;&d;&d;&d;&d;&d;&d;">
-        <!ENTITY d "&e;&e;&e;&e;&e;&e;&e;&e;&e;&e;">
-        <!ENTITY e "&f;&f;&f;&f;&f;&f;&f;&f;&f;&f;">
-        <!ENTITY f "&g;&g;&g;&g;&g;&g;&g;&g;&g;&g;">
-        <!ENTITY g "xxxxxxxxxxxxxxxxxxxxxxxxxxxxxx">
-      ]>
-      <member>
-      &a;
-      </member>
-      EOT
-
-      Hash.from_xml(attack_xml)
-    end
-  end
-
-  def test_setting_libxml_as_backend
-    XmlMini.backend = 'LibXMLSAX'
-    assert_equal XmlMini_LibXMLSAX, XmlMini.backend
-  end
-
-  def test_blank_returns_empty_hash
-    assert_equal({}, XmlMini.parse(nil))
-    assert_equal({}, XmlMini.parse(''))
-  end
-
-  def test_array_type_makes_an_array
-    assert_equal_rexml(<<-eoxml)
-      <blog>
-        <posts type="array">
-          <post>a post</post>
-          <post>another post</post>
-        </posts>
-      </blog>
-    eoxml
-  end
-
-  def test_one_node_document_as_hash
-    assert_equal_rexml(<<-eoxml)
-    <products/>
-    eoxml
-  end
-
-  def test_one_node_with_attributes_document_as_hash
-    assert_equal_rexml(<<-eoxml)
-    <products foo="bar"/>
-    eoxml
-  end
-
-  def test_products_node_with_book_node_as_hash
-    assert_equal_rexml(<<-eoxml)
-    <products>
-      <book name="awesome" id="12345" />
-    </products>
-    eoxml
-  end
-
-  def test_products_node_with_two_book_nodes_as_hash
-    assert_equal_rexml(<<-eoxml)
-    <products>
-      <book name="awesome" id="12345" />
-      <book name="america" id="67890" />
-    </products>
-    eoxml
-  end
+XMLMiniEngineTest.run_with_gem("libxml") do
+  class LibXMLSAXEngineTest < XMLMiniEngineTest
+    private
+      def engine
+        "LibXMLSAX"
+      end
 
-  def test_single_node_with_content_as_hash
-    assert_equal_rexml(<<-eoxml)
-      <products>
-        hello world
-      </products>
-    eoxml
+      def expansion_attack_error
+        LibXML::XML::Error
+      end
   end
-
-  def test_children_with_children
-    assert_equal_rexml(<<-eoxml)
-    <root>
-      <products>
-        <book name="america" id="67890" />
-      </products>
-    </root>
-    eoxml
-  end
-
-  def test_children_with_text
-    assert_equal_rexml(<<-eoxml)
-    <root>
-      <products>
-        hello everyone
-      </products>
-    </root>
-    eoxml
-  end
-
-  def test_children_with_non_adjacent_text
-    assert_equal_rexml(<<-eoxml)
-    <root>
-      good
-      <products>
-        hello everyone
-      </products>
-      morning
-    </root>
-    eoxml
-  end
-
-  def test_parse_from_io
-    io = StringIO.new(<<-eoxml)
-    <root>
-      good
-      <products>
-        hello everyone
-      </products>
-      morning
-    </root>
-    eoxml
-    assert_equal_rexml(io)
-  end
-
-  def test_children_with_simple_cdata
-    assert_equal_rexml(<<-eoxml)
-    <root>
-      <products>
-         <![CDATA[cdatablock]]>
-      </products>
-    </root>
-    eoxml
-  end
-
-  def test_children_with_multiple_cdata
-    assert_equal_rexml(<<-eoxml)
-    <root>
-      <products>
-         <![CDATA[cdatablock1]]><![CDATA[cdatablock2]]>
-      </products>
-    </root>
-    eoxml
-  end
-
-  def test_children_with_text_and_cdata
-    assert_equal_rexml(<<-eoxml)
-    <root>
-      <products>
-        hello <![CDATA[cdatablock]]>
-        morning
-      </products>
-    </root>
-    eoxml
-  end
-
-  def test_children_with_blank_text
-    assert_equal_rexml(<<-eoxml)
-    <root>
-      <products>   </products>
-    </root>
-    eoxml
-  end
-
-  private
-    def assert_equal_rexml(xml)
-      parsed_xml = XmlMini.parse(xml)
-      xml.rewind if xml.respond_to?(:rewind)
-      hash = XmlMini.with_backend('REXML') { XmlMini.parse(xml) }
-      assert_equal(hash, parsed_xml)
-    end
-end
-
 end
diff --git a/activesupport/test/xml_mini/nokogiri_engine_test.rb b/activesupport/test/xml_mini/nokogiri_engine_test.rb
index 1314c9065a..f1584bcedf 100644
--- a/activesupport/test/xml_mini/nokogiri_engine_test.rb
+++ b/activesupport/test/xml_mini/nokogiri_engine_test.rb
@@ -1,215 +1,16 @@
-begin
-  require 'nokogiri'
-rescue LoadError
-  # Skip nokogiri tests
-else
-require 'abstract_unit'
-require 'active_support/xml_mini'
-require 'active_support/core_ext/hash/conversions'
+# frozen_string_literal: true
 
-class NokogiriEngineTest < ActiveSupport::TestCase
-  def setup
-    @default_backend = ActiveSupport::XmlMini.backend
-    ActiveSupport::XmlMini.backend = 'Nokogiri'
-  end
-
-  def teardown
-    ActiveSupport::XmlMini.backend = @default_backend
-  end
-
-  def test_file_from_xml
-    hash = Hash.from_xml(<<-eoxml)
-      <blog>
-        <logo type="file" name="logo.png" content_type="image/png">
-        </logo>
-      </blog>
-    eoxml
-    assert hash.has_key?('blog')
-    assert hash['blog'].has_key?('logo')
-
-    file = hash['blog']['logo']
-    assert_equal 'logo.png', file.original_filename
-    assert_equal 'image/png', file.content_type
-  end
-
-  def test_exception_thrown_on_expansion_attack
-    assert_raise Nokogiri::XML::SyntaxError do
-      attack_xml = <<-EOT
-      <?xml version="1.0" encoding="UTF-8"?>
-      <!DOCTYPE member [
-        <!ENTITY a "&b;&b;&b;&b;&b;&b;&b;&b;&b;&b;">
-        <!ENTITY b "&c;&c;&c;&c;&c;&c;&c;&c;&c;&c;">
-        <!ENTITY c "&d;&d;&d;&d;&d;&d;&d;&d;&d;&d;">
-        <!ENTITY d "&e;&e;&e;&e;&e;&e;&e;&e;&e;&e;">
-        <!ENTITY e "&f;&f;&f;&f;&f;&f;&f;&f;&f;&f;">
-        <!ENTITY f "&g;&g;&g;&g;&g;&g;&g;&g;&g;&g;">
-        <!ENTITY g "xxxxxxxxxxxxxxxxxxxxxxxxxxxxxx">
-      ]>
-      <member>
-      &a;
-      </member>
-      EOT
-      Hash.from_xml(attack_xml)
-    end
-  end
-
-  def test_setting_nokogiri_as_backend
-    ActiveSupport::XmlMini.backend = 'Nokogiri'
-    assert_equal ActiveSupport::XmlMini_Nokogiri, ActiveSupport::XmlMini.backend
-  end
-
-  def test_blank_returns_empty_hash
-    assert_equal({}, ActiveSupport::XmlMini.parse(nil))
-    assert_equal({}, ActiveSupport::XmlMini.parse(''))
-  end
-
-  def test_array_type_makes_an_array
-    assert_equal_rexml(<<-eoxml)
-      <blog>
-        <posts type="array">
-          <post>a post</post>
-          <post>another post</post>
-        </posts>
-      </blog>
-    eoxml
-  end
-
-  def test_one_node_document_as_hash
-    assert_equal_rexml(<<-eoxml)
-    <products/>
-    eoxml
-  end
-
-  def test_one_node_with_attributes_document_as_hash
-    assert_equal_rexml(<<-eoxml)
-    <products foo="bar"/>
-    eoxml
-  end
-
-  def test_products_node_with_book_node_as_hash
-    assert_equal_rexml(<<-eoxml)
-    <products>
-      <book name="awesome" id="12345" />
-    </products>
-    eoxml
-  end
-
-  def test_products_node_with_two_book_nodes_as_hash
-    assert_equal_rexml(<<-eoxml)
-    <products>
-      <book name="awesome" id="12345" />
-      <book name="america" id="67890" />
-    </products>
-    eoxml
-  end
-
-  def test_single_node_with_content_as_hash
-    assert_equal_rexml(<<-eoxml)
-      <products>
-        hello world
-      </products>
-    eoxml
-  end
+require_relative "xml_mini_engine_test"
 
-  def test_children_with_children
-    assert_equal_rexml(<<-eoxml)
-    <root>
-      <products>
-        <book name="america" id="67890" />
-      </products>
-    </root>
-    eoxml
-  end
-
-  def test_children_with_text
-    assert_equal_rexml(<<-eoxml)
-    <root>
-      <products>
-        hello everyone
-      </products>
-    </root>
-    eoxml
-  end
+XMLMiniEngineTest.run_with_gem("nokogiri") do
+  class NokogiriEngineTest < XMLMiniEngineTest
+    private
+      def engine
+        "Nokogiri"
+      end
 
-  def test_children_with_non_adjacent_text
-    assert_equal_rexml(<<-eoxml)
-    <root>
-      good
-      <products>
-        hello everyone
-      </products>
-      morning
-    </root>
-    eoxml
+      def expansion_attack_error
+        Nokogiri::XML::SyntaxError
+      end
   end
-
-  def test_parse_from_io
-    io = StringIO.new(<<-eoxml)
-    <root>
-      good
-      <products>
-        hello everyone
-      </products>
-      morning
-    </root>
-    eoxml
-    assert_equal_rexml(io)
-  end
-
-  def test_children_with_simple_cdata
-    assert_equal_rexml(<<-eoxml)
-    <root>
-      <products>
-         <![CDATA[cdatablock]]>
-      </products>
-    </root>
-    eoxml
-  end
-
-  def test_children_with_multiple_cdata
-    assert_equal_rexml(<<-eoxml)
-    <root>
-      <products>
-         <![CDATA[cdatablock1]]><![CDATA[cdatablock2]]>
-      </products>
-    </root>
-    eoxml
-  end
-
-  def test_children_with_text_and_cdata
-    assert_equal_rexml(<<-eoxml)
-    <root>
-      <products>
-        hello <![CDATA[cdatablock]]>
-        morning
-      </products>
-    </root>
-    eoxml
-  end
-
-  def test_children_with_blank_text
-    assert_equal_rexml(<<-eoxml)
-    <root>
-      <products>   </products>
-    </root>
-    eoxml
-  end
-
-  def test_children_with_blank_text_and_attribute
-    assert_equal_rexml(<<-eoxml)
-    <root>
-      <products type="file">   </products>
-    </root>
-    eoxml
-  end
-
-  private
-    def assert_equal_rexml(xml)
-      parsed_xml = ActiveSupport::XmlMini.parse(xml)
-      xml.rewind if xml.respond_to?(:rewind)
-      hash = ActiveSupport::XmlMini.with_backend('REXML') { ActiveSupport::XmlMini.parse(xml) }
-      assert_equal(hash, parsed_xml)
-    end
-end
-
 end
diff --git a/activesupport/test/xml_mini/nokogirisax_engine_test.rb b/activesupport/test/xml_mini/nokogirisax_engine_test.rb
index 7978a50921..f38a56e83b 100644
--- a/activesupport/test/xml_mini/nokogirisax_engine_test.rb
+++ b/activesupport/test/xml_mini/nokogirisax_engine_test.rb
@@ -1,216 +1,16 @@
-begin
-  require 'nokogiri'
-rescue LoadError
-  # Skip nokogiri tests
-else
-require 'abstract_unit'
-require 'active_support/xml_mini'
-require 'active_support/core_ext/hash/conversions'
+# frozen_string_literal: true
 
-class NokogiriSAXEngineTest < ActiveSupport::TestCase
-  def setup
-    @default_backend = ActiveSupport::XmlMini.backend
-    ActiveSupport::XmlMini.backend = 'NokogiriSAX'
-  end
-
-  def teardown
-    ActiveSupport::XmlMini.backend = @default_backend
-  end
-
-  def test_file_from_xml
-    hash = Hash.from_xml(<<-eoxml)
-      <blog>
-        <logo type="file" name="logo.png" content_type="image/png">
-        </logo>
-      </blog>
-    eoxml
-    assert hash.has_key?('blog')
-    assert hash['blog'].has_key?('logo')
-
-    file = hash['blog']['logo']
-    assert_equal 'logo.png', file.original_filename
-    assert_equal 'image/png', file.content_type
-  end
-
-  def test_exception_thrown_on_expansion_attack
-    assert_raise RuntimeError do
-      attack_xml = <<-EOT
-      <?xml version="1.0" encoding="UTF-8"?>
-      <!DOCTYPE member [
-        <!ENTITY a "&b;&b;&b;&b;&b;&b;&b;&b;&b;&b;">
-        <!ENTITY b "&c;&c;&c;&c;&c;&c;&c;&c;&c;&c;">
-        <!ENTITY c "&d;&d;&d;&d;&d;&d;&d;&d;&d;&d;">
-        <!ENTITY d "&e;&e;&e;&e;&e;&e;&e;&e;&e;&e;">
-        <!ENTITY e "&f;&f;&f;&f;&f;&f;&f;&f;&f;&f;">
-        <!ENTITY f "&g;&g;&g;&g;&g;&g;&g;&g;&g;&g;">
-        <!ENTITY g "xxxxxxxxxxxxxxxxxxxxxxxxxxxxxx">
-      ]>
-      <member>
-      &a;
-      </member>
-      EOT
-
-      Hash.from_xml(attack_xml)
-    end
-  end
-
-  def test_setting_nokogirisax_as_backend
-    ActiveSupport::XmlMini.backend = 'NokogiriSAX'
-    assert_equal ActiveSupport::XmlMini_NokogiriSAX, ActiveSupport::XmlMini.backend
-  end
+require_relative "xml_mini_engine_test"
 
-  def test_blank_returns_empty_hash
-    assert_equal({}, ActiveSupport::XmlMini.parse(nil))
-    assert_equal({}, ActiveSupport::XmlMini.parse(''))
-  end
-
-  def test_array_type_makes_an_array
-    assert_equal_rexml(<<-eoxml)
-      <blog>
-        <posts type="array">
-          <post>a post</post>
-          <post>another post</post>
-        </posts>
-      </blog>
-    eoxml
-  end
-
-  def test_one_node_document_as_hash
-    assert_equal_rexml(<<-eoxml)
-    <products/>
-    eoxml
-  end
-
-  def test_one_node_with_attributes_document_as_hash
-    assert_equal_rexml(<<-eoxml)
-    <products foo="bar"/>
-    eoxml
-  end
-
-  def test_products_node_with_book_node_as_hash
-    assert_equal_rexml(<<-eoxml)
-    <products>
-      <book name="awesome" id="12345" />
-    </products>
-    eoxml
-  end
-
-  def test_products_node_with_two_book_nodes_as_hash
-    assert_equal_rexml(<<-eoxml)
-    <products>
-      <book name="awesome" id="12345" />
-      <book name="america" id="67890" />
-    </products>
-    eoxml
-  end
+XMLMiniEngineTest.run_with_gem("nokogiri") do
+  class NokogiriSAXEngineTest < XMLMiniEngineTest
+    private
+      def engine
+        "NokogiriSAX"
+      end
 
-  def test_single_node_with_content_as_hash
-    assert_equal_rexml(<<-eoxml)
-      <products>
-        hello world
-      </products>
-    eoxml
+      def expansion_attack_error
+        RuntimeError
+      end
   end
-
-  def test_children_with_children
-    assert_equal_rexml(<<-eoxml)
-    <root>
-      <products>
-        <book name="america" id="67890" />
-      </products>
-    </root>
-    eoxml
-  end
-
-  def test_children_with_text
-    assert_equal_rexml(<<-eoxml)
-    <root>
-      <products>
-        hello everyone
-      </products>
-    </root>
-    eoxml
-  end
-
-  def test_children_with_non_adjacent_text
-    assert_equal_rexml(<<-eoxml)
-    <root>
-      good
-      <products>
-        hello everyone
-      </products>
-      morning
-    </root>
-    eoxml
-  end
-
-  def test_parse_from_io
-    io = StringIO.new(<<-eoxml)
-    <root>
-      good
-      <products>
-        hello everyone
-      </products>
-      morning
-    </root>
-    eoxml
-    assert_equal_rexml(io)
-  end
-
-  def test_children_with_simple_cdata
-    assert_equal_rexml(<<-eoxml)
-    <root>
-      <products>
-         <![CDATA[cdatablock]]>
-      </products>
-    </root>
-    eoxml
-  end
-
-  def test_children_with_multiple_cdata
-    assert_equal_rexml(<<-eoxml)
-    <root>
-      <products>
-         <![CDATA[cdatablock1]]><![CDATA[cdatablock2]]>
-      </products>
-    </root>
-    eoxml
-  end
-
-  def test_children_with_text_and_cdata
-    assert_equal_rexml(<<-eoxml)
-    <root>
-      <products>
-        hello <![CDATA[cdatablock]]>
-        morning
-      </products>
-    </root>
-    eoxml
-  end
-
-  def test_children_with_blank_text
-    assert_equal_rexml(<<-eoxml)
-    <root>
-      <products>   </products>
-    </root>
-    eoxml
-  end
-
-  def test_children_with_blank_text_and_attribute
-    assert_equal_rexml(<<-eoxml)
-    <root>
-      <products type="file">   </products>
-    </root>
-    eoxml
-  end
-
-  private
-    def assert_equal_rexml(xml)
-      parsed_xml = ActiveSupport::XmlMini.parse(xml)
-      xml.rewind if xml.respond_to?(:rewind)
-      hash = ActiveSupport::XmlMini.with_backend('REXML') { ActiveSupport::XmlMini.parse(xml) }
-      assert_equal(hash, parsed_xml)
-    end
-end
-
 end
diff --git a/activesupport/test/xml_mini/rexml_engine_test.rb b/activesupport/test/xml_mini/rexml_engine_test.rb
index 6e9ce7ac11..34bf81fa75 100644
--- a/activesupport/test/xml_mini/rexml_engine_test.rb
+++ b/activesupport/test/xml_mini/rexml_engine_test.rb
@@ -1,45 +1,27 @@
-require 'abstract_unit'
-require 'active_support/xml_mini'
+# frozen_string_literal: true
 
-class REXMLEngineTest < ActiveSupport::TestCase
-  def test_default_is_rexml
-    assert_equal ActiveSupport::XmlMini_REXML, ActiveSupport::XmlMini.backend
-  end
+require_relative "xml_mini_engine_test"
 
-  def test_set_rexml_as_backend
-    ActiveSupport::XmlMini.backend = 'REXML'
+class REXMLEngineTest < XMLMiniEngineTest
+  def test_default_is_rexml
     assert_equal ActiveSupport::XmlMini_REXML, ActiveSupport::XmlMini.backend
   end
 
-  def test_parse_from_io
-    ActiveSupport::XmlMini.backend = 'REXML'
-    io = StringIO.new(<<-eoxml)
-    <root>
-      good
-      <products>
-        hello everyone
-      </products>
-      morning
-    </root>
-    eoxml
-    hash = ActiveSupport::XmlMini.parse(io)
-    assert hash.has_key?('root')
-    assert hash['root'].has_key?('products')
-    assert_match "good", hash['root']['__content__']
-    products = hash['root']['products']    
-    assert products.has_key?("__content__")    
-    assert_match 'hello everyone', products['__content__']
-  end
-
   def test_parse_from_empty_string
-    ActiveSupport::XmlMini.backend = 'REXML'
     assert_equal({}, ActiveSupport::XmlMini.parse(""))
   end
 
   def test_parse_from_frozen_string
-    ActiveSupport::XmlMini.backend = 'REXML'
     xml_string = "<root></root>".freeze
-    assert_equal({"root" => {}}, ActiveSupport::XmlMini.parse(xml_string))
+    assert_equal({ "root" => {} }, ActiveSupport::XmlMini.parse(xml_string))
   end
 
+  private
+    def engine
+      "REXML"
+    end
+
+    def expansion_attack_error
+      RuntimeError
+    end
 end
diff --git a/activesupport/test/xml_mini/xml_mini_engine_test.rb b/activesupport/test/xml_mini/xml_mini_engine_test.rb
new file mode 100644
index 0000000000..5c4c28d9b7
--- /dev/null
+++ b/activesupport/test/xml_mini/xml_mini_engine_test.rb
@@ -0,0 +1,264 @@
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "active_support/xml_mini"
+require "active_support/core_ext/hash/conversions"
+
+class XMLMiniEngineTest < ActiveSupport::TestCase
+  def self.run_with_gem(gem_name)
+    require gem_name
+    yield
+  rescue LoadError
+    # Skip tests unless gem is available
+  end
+
+  def self.run_with_platform(platform_name)
+    yield if RUBY_PLATFORM.include?(platform_name)
+  end
+
+  def self.inherited(base)
+    base.include EngineTests
+    super
+  end
+
+  def setup
+    @default_backend = ActiveSupport::XmlMini.backend
+    ActiveSupport::XmlMini.backend = engine
+    super
+  end
+
+  def teardown
+    ActiveSupport::XmlMini.backend = @default_backend
+    super
+  end
+
+  module EngineTests
+    def test_file_from_xml
+      hash = Hash.from_xml(<<-eoxml)
+        <blog>
+          <logo type="file" name="logo.png" content_type="image/png">
+          </logo>
+        </blog>
+      eoxml
+      assert hash.key?("blog")
+      assert hash["blog"].key?("logo")
+
+      file = hash["blog"]["logo"]
+      assert_equal "logo.png", file.original_filename
+      assert_equal "image/png", file.content_type
+    end
+
+    def test_exception_thrown_on_expansion_attack
+      assert_raise expansion_attack_error do
+        Hash.from_xml(<<-eoxml)
+          <?xml version="1.0" encoding="UTF-8"?>
+          <!DOCTYPE member [
+            <!ENTITY a "&b;&b;&b;&b;&b;&b;&b;&b;&b;&b;">
+            <!ENTITY b "&c;&c;&c;&c;&c;&c;&c;&c;&c;&c;">
+            <!ENTITY c "&d;&d;&d;&d;&d;&d;&d;&d;&d;&d;">
+            <!ENTITY d "&e;&e;&e;&e;&e;&e;&e;&e;&e;&e;">
+            <!ENTITY e "&f;&f;&f;&f;&f;&f;&f;&f;&f;&f;">
+            <!ENTITY f "&g;&g;&g;&g;&g;&g;&g;&g;&g;&g;">
+            <!ENTITY g "xxxxxxxxxxxxxxxxxxxxxxxxxxxxxx">
+          ]>
+          <member>
+            &a;
+          </member>
+      eoxml
+      end
+    end
+
+    def test_setting_backend
+      assert_engine_class ActiveSupport::XmlMini.backend
+    end
+
+    def test_blank_returns_empty_hash
+      assert_equal({}, ActiveSupport::XmlMini.parse(nil))
+      assert_equal({}, ActiveSupport::XmlMini.parse(""))
+    end
+
+    def test_parse_from_frozen_string
+      xml_string = "<root/>".freeze
+      assert_equal({ "root" => {} }, ActiveSupport::XmlMini.parse(xml_string))
+    end
+
+    def test_array_type_makes_an_array
+      assert_equal_rexml(<<-eoxml)
+        <blog>
+          <posts type="array">
+            <post>a post</post>
+            <post>another post</post>
+          </posts>
+        </blog>
+      eoxml
+    end
+
+    def test_one_node_document_as_hash
+      assert_equal_rexml(<<-eoxml)
+        <products/>
+      eoxml
+    end
+
+    def test_one_node_with_attributes_document_as_hash
+      assert_equal_rexml(<<-eoxml)
+        <products foo="bar"/>
+      eoxml
+    end
+
+    def test_products_node_with_book_node_as_hash
+      assert_equal_rexml(<<-eoxml)
+        <products>
+          <book name="awesome" id="12345" />
+        </products>
+      eoxml
+    end
+
+    def test_products_node_with_two_book_nodes_as_hash
+      assert_equal_rexml(<<-eoxml)
+        <products>
+          <book name="awesome" id="12345" />
+          <book name="america" id="67890" />
+        </products>
+      eoxml
+    end
+
+    def test_single_node_with_content_as_hash
+      assert_equal_rexml(<<-eoxml)
+        <products>
+          hello world
+        </products>
+      eoxml
+    end
+
+    def test_children_with_children
+      assert_equal_rexml(<<-eoxml)
+        <root>
+          <products>
+            <book name="america" id="67890" />
+          </products>
+        </root>
+      eoxml
+    end
+
+    def test_children_with_text
+      assert_equal_rexml(<<-eoxml)
+        <root>
+          <products>
+            hello everyone
+          </products>
+        </root>
+      eoxml
+    end
+
+    def test_children_with_non_adjacent_text
+      assert_equal_rexml(<<-eoxml)
+        <root>
+          good
+          <products>
+            hello everyone
+          </products>
+          morning
+        </root>
+      eoxml
+    end
+
+    def test_parse_from_io
+      skip_unless_extended_engine
+
+      assert_equal_rexml(StringIO.new(<<-eoxml))
+        <root>
+          good
+          <products>
+            hello everyone
+          </products>
+          morning
+        </root>
+      eoxml
+    end
+
+    def test_children_with_simple_cdata
+      skip_unless_extended_engine
+
+      assert_equal_rexml(<<-eoxml)
+        <root>
+          <products>
+             <![CDATA[cdatablock]]>
+          </products>
+        </root>
+      eoxml
+    end
+
+    def test_children_with_multiple_cdata
+      skip_unless_extended_engine
+
+      assert_equal_rexml(<<-eoxml)
+        <root>
+          <products>
+             <![CDATA[cdatablock1]]><![CDATA[cdatablock2]]>
+          </products>
+        </root>
+      eoxml
+    end
+
+    def test_children_with_text_and_cdata
+      skip_unless_extended_engine
+
+      assert_equal_rexml(<<-eoxml)
+        <root>
+          <products>
+            hello <![CDATA[cdatablock]]>
+            morning
+          </products>
+        </root>
+      eoxml
+    end
+
+    def test_children_with_blank_text
+      skip_unless_extended_engine
+
+      assert_equal_rexml(<<-eoxml)
+        <root>
+          <products>   </products>
+        </root>
+      eoxml
+    end
+
+    def test_children_with_blank_text_and_attribute
+      skip_unless_extended_engine
+
+      assert_equal_rexml(<<-eoxml)
+        <root>
+          <products type="file">   </products>
+        </root>
+      eoxml
+    end
+
+    private
+      def engine
+        raise NotImplementedError
+      end
+
+      def assert_engine_class(actual)
+        assert_equal ActiveSupport.const_get("XmlMini_#{engine}"), actual
+      end
+
+      def assert_equal_rexml(xml)
+        parsed_xml = ActiveSupport::XmlMini.parse(xml)
+        xml.rewind if xml.respond_to?(:rewind)
+        hash = ActiveSupport::XmlMini.with_backend("REXML") { ActiveSupport::XmlMini.parse(xml) }
+        assert_equal(hash, parsed_xml)
+      end
+
+      def expansion_attack_error
+        raise NotImplementedError
+      end
+
+      def extended_engine?
+        true
+      end
+
+      def skip_unless_extended_engine
+        skip "#{engine} is not an extended engine" unless extended_engine?
+      end
+  end
+end
diff --git a/activesupport/test/xml_mini_test.rb b/activesupport/test/xml_mini_test.rb
index 55e8181b54..18a3f2ca66 100644
--- a/activesupport/test/xml_mini_test.rb
+++ b/activesupport/test/xml_mini_test.rb
@@ -1,9 +1,11 @@
-require 'abstract_unit'
-require 'active_support/xml_mini'
-require 'active_support/builder'
-require 'active_support/core_ext/hash'
-require 'active_support/core_ext/big_decimal'
-require 'yaml'
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "active_support/xml_mini"
+require "active_support/builder"
+require "active_support/core_ext/hash"
+require "active_support/core_ext/big_decimal"
+require "yaml"
 
 module XmlMiniTest
   class RenameKeyTest < ActiveSupport::TestCase
@@ -12,23 +14,23 @@ module XmlMiniTest
     end
 
     def test_rename_key_dasherizes_with_dasherize_true
-      assert_equal "my-key", ActiveSupport::XmlMini.rename_key("my_key", :dasherize => true)
+      assert_equal "my-key", ActiveSupport::XmlMini.rename_key("my_key", dasherize: true)
     end
 
     def test_rename_key_does_nothing_with_dasherize_false
-      assert_equal "my_key", ActiveSupport::XmlMini.rename_key("my_key", :dasherize => false)
+      assert_equal "my_key", ActiveSupport::XmlMini.rename_key("my_key", dasherize: false)
     end
 
     def test_rename_key_camelizes_with_camelize_true
-      assert_equal "MyKey", ActiveSupport::XmlMini.rename_key("my_key", :camelize => true)
+      assert_equal "MyKey", ActiveSupport::XmlMini.rename_key("my_key", camelize: true)
     end
 
     def test_rename_key_lower_camelizes_with_camelize_lower
-      assert_equal "myKey", ActiveSupport::XmlMini.rename_key("my_key", :camelize => :lower)
+      assert_equal "myKey", ActiveSupport::XmlMini.rename_key("my_key", camelize: :lower)
     end
 
     def test_rename_key_lower_camelizes_with_camelize_upper
-      assert_equal "MyKey", ActiveSupport::XmlMini.rename_key("my_key", :camelize => :upper)
+      assert_equal "MyKey", ActiveSupport::XmlMini.rename_key("my_key", camelize: :upper)
     end
 
     def test_rename_key_does_not_dasherize_leading_underscores
@@ -63,16 +65,16 @@ module XmlMiniTest
 
     def setup
       @xml = ActiveSupport::XmlMini
-      @options = {:skip_instruct => true, :builder => Builder::XmlMarkup.new}
+      @options = { skip_instruct: true, builder: Builder::XmlMarkup.new }
     end
 
     test "#to_tag accepts a callable object and passes options with the builder" do
-      @xml.to_tag(:some_tag, lambda {|o| o[:builder].br }, @options)
+      @xml.to_tag(:some_tag, lambda { |o| o[:builder].br }, @options)
       assert_xml "<br/>"
     end
 
     test "#to_tag accepts a callable object and passes options and tag name" do
-      @xml.to_tag(:tag, lambda {|o, t| o[:builder].b(t) }, @options)
+      @xml.to_tag(:tag, lambda { |o, t| o[:builder].b(t) }, @options)
       assert_xml "<b>tag</b>"
     end
 
@@ -92,58 +94,58 @@ module XmlMiniTest
     end
 
     test "#to_tag should use the type value in the options hash" do
-      @xml.to_tag(:b, "blue", @options.merge(type: 'color'))
-      assert_xml( "<b type=\"color\">blue</b>" )
+      @xml.to_tag(:b, "blue", @options.merge(type: "color"))
+      assert_xml("<b type=\"color\">blue</b>")
     end
 
     test "#to_tag accepts symbol types" do
       @xml.to_tag(:b, :name, @options)
-      assert_xml( "<b type=\"symbol\">name</b>" )
+      assert_xml("<b type=\"symbol\">name</b>")
     end
 
     test "#to_tag accepts boolean types" do
       @xml.to_tag(:b, true, @options)
-      assert_xml( "<b type=\"boolean\">true</b>")
+      assert_xml("<b type=\"boolean\">true</b>")
     end
 
     test "#to_tag accepts float types" do
       @xml.to_tag(:b, 3.14, @options)
-      assert_xml( "<b type=\"float\">3.14</b>")
+      assert_xml("<b type=\"float\">3.14</b>")
     end
 
     test "#to_tag accepts decimal types" do
-      @xml.to_tag(:b, ::BigDecimal.new("1.2"), @options)
-      assert_xml( "<b type=\"decimal\">1.2</b>")
+      @xml.to_tag(:b, BigDecimal("1.2"), @options)
+      assert_xml("<b type=\"decimal\">1.2</b>")
     end
 
     test "#to_tag accepts date types" do
-      @xml.to_tag(:b, Date.new(2001,2,3), @options)
-      assert_xml( "<b type=\"date\">2001-02-03</b>")
+      @xml.to_tag(:b, Date.new(2001, 2, 3), @options)
+      assert_xml("<b type=\"date\">2001-02-03</b>")
     end
 
     test "#to_tag accepts datetime types" do
-      @xml.to_tag(:b, DateTime.new(2001,2,3,4,5,6,'+7'), @options)
-      assert_xml( "<b type=\"dateTime\">2001-02-03T04:05:06+07:00</b>")
+      @xml.to_tag(:b, DateTime.new(2001, 2, 3, 4, 5, 6, "+7"), @options)
+      assert_xml("<b type=\"dateTime\">2001-02-03T04:05:06+07:00</b>")
     end
 
     test "#to_tag accepts time types" do
       @xml.to_tag(:b, Time.new(1993, 02, 24, 12, 0, 0, "+09:00"), @options)
-      assert_xml( "<b type=\"dateTime\">1993-02-24T12:00:00+09:00</b>")
+      assert_xml("<b type=\"dateTime\">1993-02-24T12:00:00+09:00</b>")
     end
 
     test "#to_tag accepts array types" do
       @xml.to_tag(:b, ["first_name", "last_name"], @options)
-      assert_xml( "<b type=\"array\"><b>first_name</b><b>last_name</b></b>" )
+      assert_xml("<b type=\"array\"><b>first_name</b><b>last_name</b></b>")
     end
 
     test "#to_tag accepts hash types" do
       @xml.to_tag(:b, { first_name: "Bob", last_name: "Marley" }, @options)
-      assert_xml( "<b><first-name>Bob</first-name><last-name>Marley</last-name></b>" )
+      assert_xml("<b><first-name>Bob</first-name><last-name>Marley</last-name></b>")
     end
 
     test "#to_tag should not add type when skip types option is set" do
       @xml.to_tag(:b, "Bob", @options.merge(skip_types: 1))
-      assert_xml( "<b>Bob</b>" )
+      assert_xml("<b>Bob</b>")
     end
 
     test "#to_tag should dasherize the space when passed a string with spaces as a key" do
@@ -233,62 +235,62 @@ module XmlMiniTest
     end
 
     def test_symbol
-      parser = @parsing['symbol']
-      assert_equal :symbol, parser.call('symbol')
+      parser = @parsing["symbol"]
+      assert_equal :symbol, parser.call("symbol")
       assert_equal :symbol, parser.call(:symbol)
       assert_equal :'123', parser.call(123)
-      assert_raises(ArgumentError) { parser.call(Date.new(2013,11,12,02,11)) }
+      assert_raises(ArgumentError) { parser.call(Date.new(2013, 11, 12, 02, 11)) }
     end
 
     def test_date
-      parser = @parsing['date']
-      assert_equal Date.new(2013,11,12), parser.call("2013-11-12T0211Z")
+      parser = @parsing["date"]
+      assert_equal Date.new(2013, 11, 12), parser.call("2013-11-12T0211Z")
       assert_raises(TypeError) { parser.call(1384190018) }
       assert_raises(ArgumentError) { parser.call("not really a date") }
     end
 
     def test_datetime
-      parser = @parsing['datetime']
-      assert_equal Time.new(2013,11,12,02,11,00,0), parser.call("2013-11-12T02:11:00Z")
-      assert_equal DateTime.new(2013,11,12), parser.call("2013-11-12T0211Z")
-      assert_equal DateTime.new(2013,11,12,02,11), parser.call("2013-11-12T02:11Z")
-      assert_equal DateTime.new(2013,11,12,02,11), parser.call("2013-11-12T11:11+9")
+      parser = @parsing["datetime"]
+      assert_equal Time.new(2013, 11, 12, 02, 11, 00, 0), parser.call("2013-11-12T02:11:00Z")
+      assert_equal DateTime.new(2013, 11, 12), parser.call("2013-11-12T0211Z")
+      assert_equal DateTime.new(2013, 11, 12, 02, 11), parser.call("2013-11-12T02:11Z")
+      assert_equal DateTime.new(2013, 11, 12, 02, 11), parser.call("2013-11-12T11:11+9")
       assert_raises(ArgumentError) { parser.call("1384190018") }
     end
 
     def test_integer
-      parser = @parsing['integer']
+      parser = @parsing["integer"]
       assert_equal 123, parser.call(123)
       assert_equal 123, parser.call(123.003)
       assert_equal 123, parser.call("123")
       assert_equal 0, parser.call("")
-      assert_raises(ArgumentError) { parser.call(Date.new(2013,11,12,02,11)) }
+      assert_raises(ArgumentError) { parser.call(Date.new(2013, 11, 12, 02, 11)) }
     end
 
     def test_float
-      parser = @parsing['float']
+      parser = @parsing["float"]
       assert_equal 123, parser.call("123")
       assert_equal 123.003, parser.call("123.003")
       assert_equal 123.0, parser.call("123,003")
       assert_equal 0.0, parser.call("")
       assert_equal 123, parser.call(123)
       assert_equal 123.05, parser.call(123.05)
-      assert_raises(ArgumentError) { parser.call(Date.new(2013,11,12,02,11)) }
+      assert_raises(ArgumentError) { parser.call(Date.new(2013, 11, 12, 02, 11)) }
     end
 
     def test_decimal
-      parser = @parsing['decimal']
+      parser = @parsing["decimal"]
       assert_equal 123, parser.call("123")
       assert_equal 123.003, parser.call("123.003")
       assert_equal 123.0, parser.call("123,003")
       assert_equal 0.0, parser.call("")
       assert_equal 123, parser.call(123)
       assert_raises(ArgumentError) { parser.call(123.04) }
-      assert_raises(ArgumentError) { parser.call(Date.new(2013,11,12,02,11)) }
+      assert_raises(ArgumentError) { parser.call(Date.new(2013, 11, 12, 02, 11)) }
     end
 
     def test_boolean
-      parser = @parsing['boolean']
+      parser = @parsing["boolean"]
       [1, true, "1"].each do |value|
         assert parser.call(value)
       end
@@ -299,13 +301,13 @@ module XmlMiniTest
     end
 
     def test_string
-      parser = @parsing['string']
+      parser = @parsing["string"]
       assert_equal "123", parser.call(123)
       assert_equal "123", parser.call("123")
       assert_equal "[]", parser.call("[]")
       assert_equal "[]", parser.call([])
       assert_equal "{}", parser.call({})
-      assert_raises(ArgumentError) { parser.call(Date.new(2013,11,12,02,11)) }
+      assert_raises(ArgumentError) { parser.call(Date.new(2013, 11, 12, 02, 11)) }
     end
 
     def test_yaml
@@ -316,14 +318,14 @@ product:
     description : Basketball
 YAML
       expected = {
-        "product"=> [
-          {"sku"=>"BL394D", "quantity"=>4, "description"=>"Basketball"}
+        "product" => [
+          { "sku" => "BL394D", "quantity" => 4, "description" => "Basketball" }
         ]
       }
-      parser = @parsing['yaml']
+      parser = @parsing["yaml"]
       assert_equal(expected, parser.call(yaml))
-      assert_equal({1 => 'test'}, parser.call({1 => 'test'}))
-      assert_equal({"1 => 'test'"=>nil}, parser.call("{1 => 'test'}"))
+      assert_equal({ 1 => "test" }, parser.call(1 => "test"))
+      assert_equal({ "1 => 'test'" => nil }, parser.call("{1 => 'test'}"))
     end
 
     def test_base64Binary_and_binary
@@ -341,12 +343,12 @@ in the continued and indefatigable generation of knowledge, exceeds the short
 vehemence of any carnal pleasure.
 EXPECTED
 
-      parser = @parsing['base64Binary']
-      assert_equal expected_base64.gsub(/\n/," ").strip, parser.call(base64)
+      parser = @parsing["base64Binary"]
+      assert_equal expected_base64.gsub(/\n/, " ").strip, parser.call(base64)
       parser.call("NON BASE64 INPUT")
 
-      parser = @parsing['binary']
-      assert_equal expected_base64.gsub(/\n/," ").strip, parser.call(base64, 'encoding' => 'base64')
+      parser = @parsing["binary"]
+      assert_equal expected_base64.gsub(/\n/, " ").strip, parser.call(base64, "encoding" => "base64")
       assert_equal "IGNORED INPUT", parser.call("IGNORED INPUT", {})
     end
   end
diff --git a/ci/qunit-selenium-runner.rb b/ci/qunit-selenium-runner.rb
new file mode 100644
index 0000000000..3a58377d77
--- /dev/null
+++ b/ci/qunit-selenium-runner.rb
@@ -0,0 +1,15 @@
+# frozen_string_literal: true
+
+require "qunit/selenium/test_runner"
+require "chromedriver/helper"
+
+driver_options = Selenium::WebDriver::Chrome::Options.new
+driver_options.add_argument("--headless")
+driver_options.add_argument("--disable-gpu")
+
+driver = ::Selenium::WebDriver.for(:chrome, options: driver_options)
+result = QUnit::Selenium::TestRunner.new(driver).open(ARGV[0], timeout: 60)
+driver.quit
+
+puts "Time: #{result.duration} seconds, Total: #{result.assertions[:total]}, Passed: #{result.assertions[:passed]}, Failed: #{result.assertions[:failed]}"
+exit(result.tests[:failed] > 0 ? 1 : 0)
diff --git a/ci/travis.rb b/ci/travis.rb
index b8891d6889..f521ef3cf6 100755
--- a/ci/travis.rb
+++ b/ci/travis.rb
@@ -1,8 +1,14 @@
 #!/usr/bin/env ruby
-require 'fileutils'
+# frozen_string_literal: true
+
+require "fileutils"
 include FileUtils
 
 commands = [
+  'mysql -e "create user rails@localhost;"',
+  'mysql -e "grant all privileges on activerecord_unittest.* to rails@localhost;"',
+  'mysql -e "grant all privileges on activerecord_unittest2.* to rails@localhost;"',
+  'mysql -e "grant all privileges on inexistent_activerecord_unittest.* to rails@localhost;"',
   'mysql -e "create database activerecord_unittest;"',
   'mysql -e "create database activerecord_unittest2;"',
   'psql  -c "create database activerecord_unittest;" -U postgres',
@@ -10,21 +16,22 @@ commands = [
 ]
 
 commands.each do |command|
-  system("#{command} > /dev/null 2>&1")
+  system(command, [1, 2] => File::NULL)
 end
 
 class Build
   MAP = {
-    'railties' => 'railties',
-    'ap'       => 'actionpack',
-    'am'       => 'actionmailer',
-    'amo'      => 'activemodel',
-    'as'       => 'activesupport',
-    'ar'       => 'activerecord',
-    'av'       => 'actionview',
-    'aj'       => 'activejob',
-    'ac'       => 'actioncable',
-    'guides'   => 'guides'
+    "railties" => "railties",
+    "ap"       => "actionpack",
+    "am"       => "actionmailer",
+    "amo"      => "activemodel",
+    "as"       => "activesupport",
+    "ar"       => "activerecord",
+    "av"       => "actionview",
+    "aj"       => "activejob",
+    "ac"       => "actioncable",
+    "ast"      => "activestorage",
+    "guides"   => "guides"
   }
 
   attr_reader :component, :options
@@ -36,8 +43,10 @@ class Build
 
   def run!(options = {})
     self.options.update(options)
+
     Dir.chdir(dir) do
       announce(heading)
+
       if guides?
         run_bug_report_templates
       else
@@ -55,41 +64,45 @@ class Build
     heading << "with #{adapter}" if activerecord?
     heading << "in isolation" if isolated?
     heading << "integration" if integration?
-    heading.join(' ')
+    heading.join(" ")
   end
 
   def tasks
     if activerecord?
       tasks = ["#{adapter}:#{'isolated_' if isolated?}test"]
       case adapter
-      when 'mysql2'
-        tasks.unshift 'db:mysql:rebuild'
-      when 'postgresql'
-        tasks.unshift 'db:postgresql:rebuild'
+      when "mysql2"
+        tasks.unshift "db:mysql:rebuild"
+      when "postgresql"
+        tasks.unshift "db:postgresql:rebuild"
       end
       tasks
     else
-      ["test", ('isolated' if isolated?), ('integration' if integration?)].compact.join(":")
+      ["test", ("isolated" if isolated?), ("integration" if integration?), ("ujs" if ujs?)].compact.join(":")
     end
   end
 
   def key
     key = [gem]
     key << adapter if activerecord?
-    key << 'isolated' if isolated?
-    key.join(':')
+    key << "isolated" if isolated?
+    key.join(":")
   end
 
   def activesupport?
-    gem == 'activesupport'
+    gem == "activesupport"
   end
 
   def activerecord?
-    gem == 'activerecord'
+    gem == "activerecord"
   end
 
   def guides?
-    gem == 'guides'
+    gem == "guides"
+  end
+
+  def ujs?
+    component.split(":").last == "ujs"
   end
 
   def isolated?
@@ -97,16 +110,16 @@ class Build
   end
 
   def integration?
-    component.split(':').last == 'integration'
+    component.split(":").last == "integration"
   end
 
   def gem
-    MAP[component.split(':').first]
+    MAP[component.split(":").first]
   end
   alias :dir :gem
 
   def adapter
-    component.split(':').last
+    component.split(":").last
   end
 
   def rake(*tasks)
@@ -122,39 +135,41 @@ class Build
     if activesupport? && !isolated?
       # There is a known issue with the listen tests that causes files to be
       # incorrectly GC'ed even when they are still in-use. The current solution
-      # is to only run them in isolation to avoid randomly failing our test suite.
-      { 'LISTEN' => '0' }
+      # is to only run them in isolation to avoid random failures of our test suite.
+      { "LISTEN" => "0" }
     else
       {}
     end
   end
 
   def run_bug_report_templates
-    Dir.glob('bug_report_templates/*.rb').all? do |file|
-      system(Gem.ruby, '-w', file)
+    Dir.glob("bug_report_templates/*.rb").all? do |file|
+      system(Gem.ruby, "-w", file)
     end
   end
 end
 
-if ENV['GEM']=='aj:integration'
-   ENV['QC_DATABASE_URL']  = 'postgres://postgres@localhost/active_jobs_qc_int_test'
-   ENV['QUE_DATABASE_URL'] = 'postgres://postgres@localhost/active_jobs_que_int_test'
+if ENV["GEM"] == "aj:integration"
+  ENV["QC_DATABASE_URL"]  = "postgres://postgres@localhost/active_jobs_qc_int_test"
+  ENV["QUE_DATABASE_URL"] = "postgres://postgres@localhost/active_jobs_que_int_test"
 end
 
 results = {}
 
-ENV['GEM'].split(',').each do |gem|
+ENV["GEM"].split(",").each do |gem|
   [false, true].each do |isolated|
-    next if ENV['TRAVIS_PULL_REQUEST'] && ENV['TRAVIS_PULL_REQUEST'] != 'false' && isolated
-    next if gem == 'railties' && isolated
-    next if gem == 'ac' && isolated
-    next if gem == 'ac:integration' && isolated
-    next if gem == 'aj:integration' && isolated
-    next if gem == 'guides' && isolated
-
-    build = Build.new(gem, :isolated => isolated)
+    next if ENV["TRAVIS_PULL_REQUEST"] && ENV["TRAVIS_PULL_REQUEST"] != "false" && isolated
+    next if RUBY_VERSION < "2.4" && isolated
+    next if gem == "railties" && isolated
+    next if gem == "ac" && isolated
+    next if gem == "ac:integration" && isolated
+    next if gem == "aj:integration" && isolated
+    next if gem == "guides" && isolated
+    next if gem == "av:ujs" && isolated
+    next if gem == "ast" && isolated
+
+    build = Build.new(gem, isolated: isolated)
     results[build.key] = build.run!
-
   end
 end
 
diff --git a/guides/CHANGELOG.md b/guides/CHANGELOG.md
index 2730d2dfea..518b6abfb3 100644
--- a/guides/CHANGELOG.md
+++ b/guides/CHANGELOG.md
@@ -1,2 +1,10 @@
+## Rails 5.2.0.beta2 (November 28, 2017) ##
 
-Please check [5-0-stable](https://github.com/rails/rails/blob/5-0-stable/guides/CHANGELOG.md) for previous changes.
+*   No changes.
+
+
+## Rails 5.2.0.beta1 (November 27, 2017) ##
+
+*   No changes.
+
+Please check [5-1-stable](https://github.com/rails/rails/blob/5-1-stable/guides/CHANGELOG.md) for previous changes.
diff --git a/guides/Rakefile b/guides/Rakefile
index 00577377d7..84e18e0972 100644
--- a/guides/Rakefile
+++ b/guides/Rakefile
@@ -1,38 +1,52 @@
-namespace :guides do
+# frozen_string_literal: true
 
+namespace :guides do
   desc 'Generate guides (for authors), use ONLY=foo to process just "foo.md"'
-  task :generate => 'generate:html'
+  task generate: "generate:html"
+
+  # Guides are written in UTF-8, but the environment may be configured for some
+  # other locale, these tasks are responsible for ensuring the default external
+  # encoding is UTF-8.
+  #
+  # Real use cases: Generation was reported to fail on a machine configured with
+  # GBK (Chinese). The docs server once got misconfigured somehow and had "C",
+  # which broke generation too.
+  task :encoding do
+    %w(LANG LANGUAGE LC_ALL).each do |env_var|
+      ENV[env_var] = "en_US.UTF-8"
+    end
+  end
 
   namespace :generate do
-
     desc "Generate HTML guides"
-    task :html do
+    task html: :encoding do
       ENV["WARNINGS"] = "1" # authors can't disable this
       ruby "rails_guides.rb"
     end
 
     desc "Generate .mobi file. The kindlegen executable must be in your PATH. You can get it for free from http://www.amazon.com/gp/feature.html?docId=1000765211"
-    task :kindle do
-      unless `kindlerb -v 2> /dev/null` =~ /kindlerb 0.1.1/
-        abort "Please `gem install kindlerb` and make sure you have `kindlegen` in your PATH"
+    task kindle: :encoding do
+      require "kindlerb"
+      unless Kindlerb.kindlegen_available?
+        abort "Please run `setupkindlerb` to install kindlegen"
       end
-      unless `convert` =~ /convert/  
-        abort "Please install ImageMagick`"
+      unless `convert` =~ /convert/
+        abort "Please install ImageMagick"
       end
-      ENV['KINDLE'] = '1'
-      Rake::Task['guides:generate:html'].invoke
+      ENV["KINDLE"] = "1"
+      Rake::Task["guides:generate:html"].invoke
     end
   end
 
   # Validate guides -------------------------------------------------------------------------
   desc 'Validate guides, use ONLY=foo to process just "foo.html"'
-  task :validate do
+  task validate: :encoding do
     ruby "w3c_validator.rb"
   end
 
   desc "Show help"
   task :help do
-    puts <<-help
+    puts <<HELP
 
 Guides are taken from the source directory, and the result goes into the
 output directory. Assets are stored under files, and copied to output/files as
@@ -45,8 +59,9 @@ All of these processes are handled via rake tasks, here's a full list of them:
 #{%x[rake -T]}
 Some arguments may be passed via environment variables:
 
-  WARNINGS=1
-    Internal links (anchors) are checked, also detects duplicated IDs.
+  RAILS_VERSION=tag
+    If guides are being generated for a specific Rails version set the Git tag
+    here, otherwise the current SHA1 is going to be used to generate edge guides.
 
   ALL=1
     Force generation of all guides.
@@ -64,16 +79,13 @@ Some arguments may be passed via environment variables:
     Use it when you want to generate translated guides in
     source/<GUIDES_LANGUAGE> folder (such as source/es)
 
-  EDGE=1
-    Indicate generated guides should be marked as edge.
-
 Examples:
-  $ rake guides:generate ALL=1
-  $ rake guides:generate EDGE=1
-  $ rake guides:generate:kindle EDGE=1
+  $ rake guides:generate ALL=1 RAILS_VERSION=v5.1.0
+  $ rake guides:generate ONLY=migrations
+  $ rake guides:generate:kindle
   $ rake guides:generate GUIDES_LANGUAGE=es
-    help
+HELP
   end
 end
 
-task :default => 'guides:help'
+task default: "guides:help"
diff --git a/guides/assets/images/belongs_to.png b/guides/assets/images/belongs_to.png
index 077d237e4e..2b8c1d52ea 100644
--- a/guides/assets/images/belongs_to.png
+++ b/guides/assets/images/belongs_to.png
diff --git a/guides/assets/images/getting_started/article_with_comments.png b/guides/assets/images/getting_started/article_with_comments.png
index c489e4c00e..3f16f3b280 100644
--- a/guides/assets/images/getting_started/article_with_comments.png
+++ b/guides/assets/images/getting_started/article_with_comments.png
diff --git a/guides/assets/images/getting_started/challenge.png b/guides/assets/images/getting_started/challenge.png
index 5b88a842b2..d05ef31bbe 100644
--- a/guides/assets/images/getting_started/challenge.png
+++ b/guides/assets/images/getting_started/challenge.png
diff --git a/guides/assets/images/getting_started/confirm_dialog.png b/guides/assets/images/getting_started/confirm_dialog.png
index 9755f581a6..ce65734e6c 100644
--- a/guides/assets/images/getting_started/confirm_dialog.png
+++ b/guides/assets/images/getting_started/confirm_dialog.png
diff --git a/guides/assets/images/getting_started/forbidden_attributes_for_new_article.png b/guides/assets/images/getting_started/forbidden_attributes_for_new_article.png
index 9f32c68472..50b178808e 100644
--- a/guides/assets/images/getting_started/forbidden_attributes_for_new_article.png
+++ b/guides/assets/images/getting_started/forbidden_attributes_for_new_article.png
diff --git a/guides/assets/images/getting_started/form_with_errors.png b/guides/assets/images/getting_started/form_with_errors.png
index 98bff37d4a..6eefd2885a 100644
--- a/guides/assets/images/getting_started/form_with_errors.png
+++ b/guides/assets/images/getting_started/form_with_errors.png
diff --git a/guides/assets/images/getting_started/index_action_with_edit_link.png b/guides/assets/images/getting_started/index_action_with_edit_link.png
index 0566a3ffde..a2a087a598 100644
--- a/guides/assets/images/getting_started/index_action_with_edit_link.png
+++ b/guides/assets/images/getting_started/index_action_with_edit_link.png
diff --git a/guides/assets/images/getting_started/new_article.png b/guides/assets/images/getting_started/new_article.png
index bd3ae4fa67..6edcc161b6 100644
--- a/guides/assets/images/getting_started/new_article.png
+++ b/guides/assets/images/getting_started/new_article.png
diff --git a/guides/assets/images/getting_started/rails_welcome.png b/guides/assets/images/getting_started/rails_welcome.png
index baccb11322..44f89ec8de 100644
--- a/guides/assets/images/getting_started/rails_welcome.png
+++ b/guides/assets/images/getting_started/rails_welcome.png
diff --git a/guides/assets/images/getting_started/routing_error_no_controller.png b/guides/assets/images/getting_started/routing_error_no_controller.png
index ed62862291..52150f0426 100644
--- a/guides/assets/images/getting_started/routing_error_no_controller.png
+++ b/guides/assets/images/getting_started/routing_error_no_controller.png
diff --git a/guides/assets/images/getting_started/show_action_for_articles.png b/guides/assets/images/getting_started/show_action_for_articles.png
index 4dad704f89..68837131f7 100644
--- a/guides/assets/images/getting_started/show_action_for_articles.png
+++ b/guides/assets/images/getting_started/show_action_for_articles.png
diff --git a/guides/assets/images/getting_started/template_is_missing_articles_new.png b/guides/assets/images/getting_started/template_is_missing_articles_new.png
index 4e636d09ff..a1603f5d28 100644
--- a/guides/assets/images/getting_started/template_is_missing_articles_new.png
+++ b/guides/assets/images/getting_started/template_is_missing_articles_new.png
diff --git a/guides/assets/images/getting_started/unknown_action_create_for_articles.png b/guides/assets/images/getting_started/unknown_action_create_for_articles.png
index fd20cd53dc..ec4758e085 100644
--- a/guides/assets/images/getting_started/unknown_action_create_for_articles.png
+++ b/guides/assets/images/getting_started/unknown_action_create_for_articles.png
diff --git a/guides/assets/images/getting_started/unknown_action_new_for_articles.png b/guides/assets/images/getting_started/unknown_action_new_for_articles.png
index e948a51e4a..f7e7464d61 100644
--- a/guides/assets/images/getting_started/unknown_action_new_for_articles.png
+++ b/guides/assets/images/getting_started/unknown_action_new_for_articles.png
diff --git a/guides/assets/images/habtm.png b/guides/assets/images/habtm.png
index b062bc73fe..7e508cc1a6 100644
--- a/guides/assets/images/habtm.png
+++ b/guides/assets/images/habtm.png
diff --git a/guides/assets/images/has_many.png b/guides/assets/images/has_many.png
index 79da2613d7..36ccf9f0f6 100644
--- a/guides/assets/images/has_many.png
+++ b/guides/assets/images/has_many.png
diff --git a/guides/assets/images/has_many_through.png b/guides/assets/images/has_many_through.png
index 858c898dc1..9e9caabd73 100644
--- a/guides/assets/images/has_many_through.png
+++ b/guides/assets/images/has_many_through.png
diff --git a/guides/assets/images/has_one.png b/guides/assets/images/has_one.png
index 93faa05b07..c29c6b9c59 100644
--- a/guides/assets/images/has_one.png
+++ b/guides/assets/images/has_one.png
diff --git a/guides/assets/images/has_one_through.png b/guides/assets/images/has_one_through.png
index 07dac1a27d..fdf13286c4 100644
--- a/guides/assets/images/has_one_through.png
+++ b/guides/assets/images/has_one_through.png
diff --git a/guides/assets/images/header_backdrop.png b/guides/assets/images/header_backdrop.png
index 72b030478f..81f4d91774 100644
--- a/guides/assets/images/header_backdrop.png
+++ b/guides/assets/images/header_backdrop.png
diff --git a/guides/assets/images/i18n/demo_html_safe.png b/guides/assets/images/i18n/demo_html_safe.png
index 9afa8ebec1..be75d4830e 100644
--- a/guides/assets/images/i18n/demo_html_safe.png
+++ b/guides/assets/images/i18n/demo_html_safe.png
diff --git a/guides/assets/images/i18n/demo_localized_pirate.png b/guides/assets/images/i18n/demo_localized_pirate.png
index bf8d0b558c..528cc27900 100644
--- a/guides/assets/images/i18n/demo_localized_pirate.png
+++ b/guides/assets/images/i18n/demo_localized_pirate.png
diff --git a/guides/assets/images/i18n/demo_translated_en.png b/guides/assets/images/i18n/demo_translated_en.png
index e887bfa306..bbb5e93c3a 100644
--- a/guides/assets/images/i18n/demo_translated_en.png
+++ b/guides/assets/images/i18n/demo_translated_en.png
diff --git a/guides/assets/images/i18n/demo_translated_pirate.png b/guides/assets/images/i18n/demo_translated_pirate.png
index aa5618a865..305fa93a14 100644
--- a/guides/assets/images/i18n/demo_translated_pirate.png
+++ b/guides/assets/images/i18n/demo_translated_pirate.png
diff --git a/guides/assets/images/i18n/demo_translation_missing.png b/guides/assets/images/i18n/demo_translation_missing.png
index 867aa7c42d..e9833ba307 100644
--- a/guides/assets/images/i18n/demo_translation_missing.png
+++ b/guides/assets/images/i18n/demo_translation_missing.png
diff --git a/guides/assets/images/i18n/demo_untranslated.png b/guides/assets/images/i18n/demo_untranslated.png
index 2ea6404822..2653abc491 100644
--- a/guides/assets/images/i18n/demo_untranslated.png
+++ b/guides/assets/images/i18n/demo_untranslated.png
diff --git a/guides/assets/images/icons/callouts/14.png b/guides/assets/images/icons/callouts/14.png
index 4274e6580a..dbde9ca749 100644
--- a/guides/assets/images/icons/callouts/14.png
+++ b/guides/assets/images/icons/callouts/14.png
diff --git a/guides/assets/images/icons/example.png b/guides/assets/images/icons/example.png
index de23c0aa87..a0e855befa 100644
--- a/guides/assets/images/icons/example.png
+++ b/guides/assets/images/icons/example.png
diff --git a/guides/assets/images/icons/home.png b/guides/assets/images/icons/home.png
index 24149d6e78..e70e164522 100644
--- a/guides/assets/images/icons/home.png
+++ b/guides/assets/images/icons/home.png
diff --git a/guides/assets/images/icons/important.png b/guides/assets/images/icons/important.png
index dafcf0f59e..bab53bf3aa 100644
--- a/guides/assets/images/icons/important.png
+++ b/guides/assets/images/icons/important.png
diff --git a/guides/assets/images/icons/next.png b/guides/assets/images/icons/next.png
index 355b329f5a..a158832725 100644
--- a/guides/assets/images/icons/next.png
+++ b/guides/assets/images/icons/next.png
diff --git a/guides/assets/images/icons/note.png b/guides/assets/images/icons/note.png
index 08d35a6f5c..62eec7845f 100644
--- a/guides/assets/images/icons/note.png
+++ b/guides/assets/images/icons/note.png
diff --git a/guides/assets/images/icons/prev.png b/guides/assets/images/icons/prev.png
index ea564c865e..8a96960422 100644
--- a/guides/assets/images/icons/prev.png
+++ b/guides/assets/images/icons/prev.png
diff --git a/guides/assets/images/icons/tip.png b/guides/assets/images/icons/tip.png
index d834e6d1bb..a5316d318f 100644
--- a/guides/assets/images/icons/tip.png
+++ b/guides/assets/images/icons/tip.png
diff --git a/guides/assets/images/icons/up.png b/guides/assets/images/icons/up.png
index 379f0045af..6cac818170 100644
--- a/guides/assets/images/icons/up.png
+++ b/guides/assets/images/icons/up.png
diff --git a/guides/assets/images/polymorphic.png b/guides/assets/images/polymorphic.png
index a3cbc4502a..d630db9e01 100644
--- a/guides/assets/images/polymorphic.png
+++ b/guides/assets/images/polymorphic.png
diff --git a/guides/assets/images/rails4_features.png b/guides/assets/images/rails4_features.png
index b3bd5ef69e..ac73f05cf7 100644
--- a/guides/assets/images/rails4_features.png
+++ b/guides/assets/images/rails4_features.png
diff --git a/guides/assets/images/session_fixation.png b/guides/assets/images/session_fixation.png
index ac3ab01614..e009484f09 100644
--- a/guides/assets/images/session_fixation.png
+++ b/guides/assets/images/session_fixation.png
diff --git a/guides/assets/images/tab_yellow.png b/guides/assets/images/tab_yellow.png
index 3ab1c56c4d..053c807d28 100644
--- a/guides/assets/images/tab_yellow.png
+++ b/guides/assets/images/tab_yellow.png
diff --git a/guides/assets/javascripts/guides.js b/guides/assets/javascripts/guides.js
index a9c7f0d016..e4d25dfb21 100644
--- a/guides/assets/javascripts/guides.js
+++ b/guides/assets/javascripts/guides.js
@@ -51,9 +51,3 @@ var guidesIndex = {
     window.location = url;
   }
 };
-
-// Disable autolink inside example code blocks of guides.
-$(document).ready(function() {
-  SyntaxHighlighter.defaults['auto-links'] = false;
-  SyntaxHighlighter.all();
-});
diff --git a/guides/assets/javascripts/syntaxhighlighter.js b/guides/assets/javascripts/syntaxhighlighter.js
new file mode 100644
index 0000000000..584aaed716
--- /dev/null
+++ b/guides/assets/javascripts/syntaxhighlighter.js
@@ -0,0 +1,20 @@
+/*!
+ * SyntaxHighlighter
+ * https://github.com/syntaxhighlighter/syntaxhighlighter
+ *
+ * SyntaxHighlighter is donationware. If you are using it, please donate.
+ * http://alexgorbatchev.com/SyntaxHighlighter/donate.html
+ *
+ * @version
+ * 4.0.1 (Sun, 03 Jul 2016 06:45:54 GMT)
+ *
+ * @copyright
+ * Copyright (C) 2004-2016 Alex Gorbatchev.
+ *
+ * @license
+ * Dual licensed under the MIT and GPL licenses.
+ */
+
+
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r=t[n];r.enumerable=r.enumerable||!1,r.configurable=!0,"value"in r&&(r.writable=!0),Object.defineProperty(e,r.key,r)}}return function(t,n,r){return n&&e(t.prototype,n),r&&e(t,r),t}}(),s=n(9),o=r(s),l=n(3),u=n(5);e.exports=function(){function e(){i(this,e)}return a(e,[{key:"getKeywords",value:function(e){var t=e.replace(/^\s+|\s+$/g,"").replace(/\s+/g,"|");return"\\b(?:"+t+")\\b"}},{key:"forHtmlScript",value:function(e){var t={end:e.right.source};e.eof&&(t.end="(?:(?:"+t.end+")|$)"),this.htmlScript={left:{regex:e.left,css:"script"},right:{regex:e.right,css:"script"},code:(0,l.XRegExp)("(?<left>"+e.left.source+")(?<code>.*?)(?<right>"+t.end+")","sgi")}}},{key:"getHtml",value:function(e){var t=arguments.length<=1||void 0===arguments[1]?{}:arguments[1],n=(0,u.applyRegexList)(e,this.regexList),r=new o["default"](e,n,t);return r.getHtml()}}]),e}()},function(e,t,n){"use strict";function r(){var e="break case catch class continue default delete do else enum export extends false  for from as function if implements import in instanceof interface let new null package private protected static return super switch this throw true try typeof var while with yield";this.regexList=[{regex:a.multiLineDoubleQuotedString,css:"string"},{regex:a.multiLineSingleQuotedString,css:"string"},{regex:a.singleLineCComments,css:"comments"},{regex:a.multiLineCComments,css:"comments"},{regex:/\s*#.*/gm,css:"preprocessor"},{regex:new RegExp(this.getKeywords(e),"gm"),css:"keyword"}],this.forHtmlScript(a.scriptScriptTags)}var i=n(22),a=n(3).commonRegExp;r.prototype=new i,r.aliases=["js","jscript","javascript","json"],e.exports=r},function(e,t,n){"use strict";function r(){var e="alias and BEGIN begin break case class def define_method defined do each else elsif END end ensure false for if in module new next nil not or raise redo rescue retry return self super then throw true undef unless until when while yield",t="Array Bignum Binding Class Continuation Dir Exception FalseClass File::Stat File Fixnum Fload Hash Integer IO MatchData Method Module NilClass Numeric Object Proc Range Regexp String Struct::TMS Symbol ThreadGroup Thread Time TrueClass";this.regexList=[{regex:a.singleLinePerlComments,css:"comments"},{regex:a.doubleQuotedString,css:"string"},{regex:a.singleQuotedString,css:"string"},{regex:/\b[A-Z0-9_]+\b/g,css:"constants"},{regex:/:[a-z][A-Za-z0-9_]*/g,css:"color2"},{regex:/(\$|@@|@)\w+/g,css:"variable bold"},{regex:new RegExp(this.getKeywords(e),"gm"),css:"keyword"},{regex:new RegExp(this.getKeywords(t),"gm"),css:"color1"}],this.forHtmlScript(a.aspScriptTags)}var i=n(22),a=n(3).commonRegExp;r.prototype=new i,r.aliases=["ruby","rails","ror","rb"],e.exports=r},function(e,t,n){"use strict";function r(){function e(e,t){var n=e[0],r=s.exec(n,s("(&lt;|<)[\\s\\/\\?!]*(?<name>[:\\w-\\.]+)","xg")),i=[];if(null!=e.attributes)for(var a,l=0,u=s("(?<name> [\\w:.-]+)\\s*=\\s*(?<value> \".*?\"|'.*?'|\\w+)","xg");null!=(a=s.exec(n,u,l));)i.push(new o(a.name,e.index+a.index,"color1")),i.push(new o(a.value,e.index+a.index+a[0].indexOf(a.value),"string")),l=a.index+a[0].length;return null!=r&&i.push(new o(r.name,e.index+r[0].indexOf(r.name),"keyword")),i}this.regexList=[{regex:s("(\\&lt;|<)\\!\\[[\\w\\s]*?\\[(.|\\s)*?\\]\\](\\&gt;|>)","gm"),css:"color2"},{regex:a.xmlComments,css:"comments"},{regex:s("(&lt;|<)[\\s\\/\\?!]*(\\w+)(?<attributes>.*?)[\\s\\/\\?]*(&gt;|>)","sg"),func:e}]}var i=n(22),a=n(3).commonRegExp,s=n(3).XRegExp,o=n(5).Match;r.prototype=new i,r.aliases=["xml","xhtml","xslt","html","plist"],e.exports=r},function(e,t,n){"use strict";function r(){var e="abs avg case cast coalesce convert count current_timestamp current_user day isnull left lower month nullif replace right session_user space substring sum system_user upper user year",t="absolute action add after alter as asc at authorization begin bigint binary bit by cascade char character check checkpoint close collate column commit committed connect connection constraint contains continue create cube current current_date current_time cursor database date deallocate dec decimal declare default delete desc distinct double drop dynamic else end end-exec escape except exec execute false fetch first float for force foreign forward free from full function global goto grant group grouping having hour ignore index inner insensitive insert instead int integer intersect into is isolation key last level load local max min minute modify move name national nchar next no numeric of off on only open option order out output partial password precision prepare primary prior privileges procedure public read real references relative repeatable restrict return returns revoke rollback rollup rows rule schema scroll second section select sequence serializable set size smallint static statistics table temp temporary then time timestamp to top transaction translation trigger true truncate uncommitted union unique update values varchar varying view when where with work",n="all and any between cross in join like not null or outer some";
+  this.regexList=[{regex:/--(.*)$/gm,css:"comments"},{regex:/\/\*([^\*][\s\S]*?)?\*\//gm,css:"comments"},{regex:a.multiLineDoubleQuotedString,css:"string"},{regex:a.multiLineSingleQuotedString,css:"string"},{regex:new RegExp(this.getKeywords(e),"gmi"),css:"color2"},{regex:new RegExp(this.getKeywords(n),"gmi"),css:"color1"},{regex:new RegExp(this.getKeywords(t),"gmi"),css:"keyword"}]}var i=n(22),a=n(3).commonRegExp;r.prototype=new i,r.aliases=["sql"],e.exports=r},function(e,t,n){"use strict";function r(){this.regexList=[]}var i=n(22);n(3).commonRegExp;r.prototype=new i,r.aliases=["text","plain"],e.exports=r},function(e,t,n){"use strict";"function"==typeof Symbol&&"symbol"==typeof Symbol.iterator?function(e){return typeof e}:function(e){return e&&"function"==typeof Symbol&&e.constructor===Symbol?"symbol":typeof e};!function(t,n){e.exports=n()}("domready",function(){var e,t=[],n=document,r=n.documentElement.doScroll,i="DOMContentLoaded",a=(r?/^loaded|^c/:/^loaded|^i|^c/).test(n.readyState);return a||n.addEventListener(i,e=function(){for(n.removeEventListener(i,e),a=1;e=t.shift();)e()}),function(e){a?setTimeout(e,0):t.push(e)}})},function(e,t){"use strict";Object.defineProperty(t,"__esModule",{value:!0});var n=t.string=function(e){return e.replace(/^([A-Z])/g,function(e,t){return t.toLowerCase()}).replace(/([A-Z])/g,function(e,t){return"-"+t.toLowerCase()})};t.object=function(e){var t={};return Object.keys(e).forEach(function(r){return t[n(r)]=e[r]}),t}},function(e,t,n){"use strict";function r(e){return e&&e.__esModule?e:{"default":e}}var i=n(1),a=r(i);window.SyntaxHighlighter=a["default"],"undefined"==typeof window.XRegExp&&(window.XRegExp=n(3).XRegExp)}]);
diff --git a/guides/assets/javascripts/syntaxhighlighter/shBrushAS3.js b/guides/assets/javascripts/syntaxhighlighter/shBrushAS3.js
deleted file mode 100644
index 8aa3ed2732..0000000000
--- a/guides/assets/javascripts/syntaxhighlighter/shBrushAS3.js
+++ /dev/null
@@ -1,59 +0,0 @@
-/**
- * SyntaxHighlighter
- * http://alexgorbatchev.com/SyntaxHighlighter
- *
- * SyntaxHighlighter is donationware. If you are using it, please donate.
- * http://alexgorbatchev.com/SyntaxHighlighter/donate.html
- *
- * @version
- * 3.0.83 (July 02 2010)
- * 
- * @copyright
- * Copyright (C) 2004-2010 Alex Gorbatchev.
- *
- * @license
- * Dual licensed under the MIT and GPL licenses.
- */
-;(function()
-{
-	// CommonJS
-	typeof(require) != 'undefined' ? SyntaxHighlighter = require('shCore').SyntaxHighlighter : null;
-
-	function Brush()
-	{
-		// Created by Peter Atoria @ http://iAtoria.com
-	
-		var inits 	 =  'class interface function package';
-	
-		var keywords =	'-Infinity ...rest Array as AS3 Boolean break case catch const continue Date decodeURI ' + 
-						'decodeURIComponent default delete do dynamic each else encodeURI encodeURIComponent escape ' + 
-						'extends false final finally flash_proxy for get if implements import in include Infinity ' + 
-						'instanceof int internal is isFinite isNaN isXMLName label namespace NaN native new null ' + 
-						'Null Number Object object_proxy override parseFloat parseInt private protected public ' + 
-						'return set static String super switch this throw true try typeof uint undefined unescape ' + 
-						'use void while with'
-						;
-	
-		this.regexList = [
-			{ regex: SyntaxHighlighter.regexLib.singleLineCComments,	css: 'comments' },		// one line comments
-			{ regex: SyntaxHighlighter.regexLib.multiLineCComments,		css: 'comments' },		// multiline comments
-			{ regex: SyntaxHighlighter.regexLib.doubleQuotedString,		css: 'string' },		// double quoted strings
-			{ regex: SyntaxHighlighter.regexLib.singleQuotedString,		css: 'string' },		// single quoted strings
-			{ regex: /\b([\d]+(\.[\d]+)?|0x[a-f0-9]+)\b/gi,				css: 'value' },			// numbers
-			{ regex: new RegExp(this.getKeywords(inits), 'gm'),			css: 'color3' },		// initializations
-			{ regex: new RegExp(this.getKeywords(keywords), 'gm'),		css: 'keyword' },		// keywords
-			{ regex: new RegExp('var', 'gm'),							css: 'variable' },		// variable
-			{ regex: new RegExp('trace', 'gm'),							css: 'color1' }			// trace
-			];
-	
-		this.forHtmlScript(SyntaxHighlighter.regexLib.scriptScriptTags);
-	};
-
-	Brush.prototype	= new SyntaxHighlighter.Highlighter();
-	Brush.aliases	= ['actionscript3', 'as3'];
-
-	SyntaxHighlighter.brushes.AS3 = Brush;
-
-	// CommonJS
-	typeof(exports) != 'undefined' ? exports.Brush = Brush : null;
-})();
diff --git a/guides/assets/javascripts/syntaxhighlighter/shBrushAppleScript.js b/guides/assets/javascripts/syntaxhighlighter/shBrushAppleScript.js
deleted file mode 100644
index d40bbd7dd2..0000000000
--- a/guides/assets/javascripts/syntaxhighlighter/shBrushAppleScript.js
+++ /dev/null
@@ -1,75 +0,0 @@
-/**
- * SyntaxHighlighter
- * http://alexgorbatchev.com/SyntaxHighlighter
- *
- * SyntaxHighlighter is donationware. If you are using it, please donate.
- * http://alexgorbatchev.com/SyntaxHighlighter/donate.html
- *
- * @version
- * 3.0.83 (July 02 2010)
- * 
- * @copyright
- * Copyright (C) 2004-2010 Alex Gorbatchev.
- *
- * @license
- * Dual licensed under the MIT and GPL licenses.
- */
-;(function()
-{
-	// CommonJS
-	typeof(require) != 'undefined' ? SyntaxHighlighter = require('shCore').SyntaxHighlighter : null;
-
-	function Brush()
-	{
-		// AppleScript brush by David Chambers
-		// http://davidchambersdesign.com/
-		var keywords   = 'after before beginning continue copy each end every from return get global in local named of set some that the then times to where whose with without';
-		var ordinals   = 'first second third fourth fifth sixth seventh eighth ninth tenth last front back middle';
-		var specials   = 'activate add alias AppleScript ask attachment boolean class constant delete duplicate empty exists false id integer list make message modal modified new no paragraph pi properties quit real record remove rest result reveal reverse run running save string true word yes';
-
-		this.regexList = [
-
-			{ regex: /(--|#).*$/gm,
-			    css: 'comments' },
-
-			{ regex: /\(\*(?:[\s\S]*?\(\*[\s\S]*?\*\))*[\s\S]*?\*\)/gm, // support nested comments
-			    css: 'comments' },
-
-			{ regex: /"[\s\S]*?"/gm,
-			    css: 'string' },
-
-			{ regex: /(?:,|:|¬|'s\b|\(|\)|\{|\}|«|\b\w*»)/g,
-			    css: 'color1' },
-
-			{ regex: /(-)?(\d)+(\.(\d)?)?(E\+(\d)+)?/g, // numbers
-			    css: 'color1' },
-
-			{ regex: /(?:&(amp;|gt;|lt;)?|=|� |>|<|≥|>=|≤|<=|\*|\+|-|\/|÷|\^)/g,
-			    css: 'color2' },
-
-			{ regex: /\b(?:and|as|div|mod|not|or|return(?!\s&)(ing)?|equals|(is(n't| not)? )?equal( to)?|does(n't| not) equal|(is(n't| not)? )?(greater|less) than( or equal( to)?)?|(comes|does(n't| not) come) (after|before)|is(n't| not)?( in)? (back|front) of|is(n't| not)? behind|is(n't| not)?( (in|contained by))?|does(n't| not) contain|contain(s)?|(start|begin|end)(s)? with|((but|end) )?(consider|ignor)ing|prop(erty)?|(a )?ref(erence)?( to)?|repeat (until|while|with)|((end|exit) )?repeat|((else|end) )?if|else|(end )?(script|tell|try)|(on )?error|(put )?into|(of )?(it|me)|its|my|with (timeout( of)?|transaction)|end (timeout|transaction))\b/g,
-			    css: 'keyword' },
-
-			{ regex: /\b\d+(st|nd|rd|th)\b/g, // ordinals
-			    css: 'keyword' },
-
-			{ regex: /\b(?:about|above|against|around|at|below|beneath|beside|between|by|(apart|aside) from|(instead|out) of|into|on(to)?|over|since|thr(ough|u)|under)\b/g,
-			    css: 'color3' },
-
-			{ regex: /\b(?:adding folder items to|after receiving|choose( ((remote )?application|color|folder|from list|URL))?|clipboard info|set the clipboard to|(the )?clipboard|entire contents|display(ing| (alert|dialog|mode))?|document( (edited|file|nib name))?|file( (name|type))?|(info )?for|giving up after|(name )?extension|quoted form|return(ed)?|second(?! item)(s)?|list (disks|folder)|text item(s| delimiters)?|(Unicode )?text|(disk )?item(s)?|((current|list) )?view|((container|key) )?window|with (data|icon( (caution|note|stop))?|parameter(s)?|prompt|properties|seed|title)|case|diacriticals|hyphens|numeric strings|punctuation|white space|folder creation|application(s( folder)?| (processes|scripts position|support))?|((desktop )?(pictures )?|(documents|downloads|favorites|home|keychain|library|movies|music|public|scripts|sites|system|users|utilities|workflows) )folder|desktop|Folder Action scripts|font(s| panel)?|help|internet plugins|modem scripts|(system )?preferences|printer descriptions|scripting (additions|components)|shared (documents|libraries)|startup (disk|items)|temporary items|trash|on server|in AppleTalk zone|((as|long|short) )?user name|user (ID|locale)|(with )?password|in (bundle( with identifier)?|directory)|(close|open for) access|read|write( permission)?|(g|s)et eof|using( delimiters)?|starting at|default (answer|button|color|country code|entr(y|ies)|identifiers|items|name|location|script editor)|hidden( answer)?|open(ed| (location|untitled))?|error (handling|reporting)|(do( shell)?|load|run|store) script|administrator privileges|altering line endings|get volume settings|(alert|boot|input|mount|output|set) volume|output muted|(fax|random )?number|round(ing)?|up|down|toward zero|to nearest|as taught in school|system (attribute|info)|((AppleScript( Studio)?|system) )?version|(home )?directory|(IPv4|primary Ethernet) address|CPU (type|speed)|physical memory|time (stamp|to GMT)|replacing|ASCII (character|number)|localized string|from table|offset|summarize|beep|delay|say|(empty|multiple) selections allowed|(of|preferred) type|invisibles|showing( package contents)?|editable URL|(File|FTP|News|Media|Web) [Ss]ervers|Telnet hosts|Directory services|Remote applications|waiting until completion|saving( (in|to))?|path (for|to( (((current|frontmost) )?application|resource))?)|POSIX (file|path)|(background|RGB) color|(OK|cancel) button name|cancel button|button(s)?|cubic ((centi)?met(re|er)s|yards|feet|inches)|square ((kilo)?met(re|er)s|miles|yards|feet)|(centi|kilo)?met(re|er)s|miles|yards|feet|inches|lit(re|er)s|gallons|quarts|(kilo)?grams|ounces|pounds|degrees (Celsius|Fahrenheit|Kelvin)|print( (dialog|settings))?|clos(e(able)?|ing)|(de)?miniaturized|miniaturizable|zoom(ed|able)|attribute run|action (method|property|title)|phone|email|((start|end)ing|home) page|((birth|creation|current|custom|modification) )?date|((((phonetic )?(first|last|middle))|computer|host|maiden|related) |nick)?name|aim|icq|jabber|msn|yahoo|address(es)?|save addressbook|should enable action|city|country( code)?|formatte(r|d address)|(palette )?label|state|street|zip|AIM [Hh]andle(s)?|my card|select(ion| all)?|unsaved|(alpha )?value|entr(y|ies)|group|(ICQ|Jabber|MSN) handle|person|people|company|department|icon image|job title|note|organization|suffix|vcard|url|copies|collating|pages (across|down)|request print time|target( printer)?|((GUI Scripting|Script menu) )?enabled|show Computer scripts|(de)?activated|awake from nib|became (key|main)|call method|of (class|object)|center|clicked toolbar item|closed|for document|exposed|(can )?hide|idle|keyboard (down|up)|event( (number|type))?|launch(ed)?|load (image|movie|nib|sound)|owner|log|mouse (down|dragged|entered|exited|moved|up)|move|column|localization|resource|script|register|drag (info|types)|resigned (active|key|main)|resiz(e(d)?|able)|right mouse (down|dragged|up)|scroll wheel|(at )?index|should (close|open( untitled)?|quit( after last window closed)?|zoom)|((proposed|screen) )?bounds|show(n)?|behind|in front of|size (mode|to fit)|update(d| toolbar item)?|was (hidden|miniaturized)|will (become active|close|finish launching|hide|miniaturize|move|open|quit|(resign )?active|((maximum|minimum|proposed) )?size|show|zoom)|bundle|data source|movie|pasteboard|sound|tool(bar| tip)|(color|open|save) panel|coordinate system|frontmost|main( (bundle|menu|window))?|((services|(excluded from )?windows) )?menu|((executable|frameworks|resource|scripts|shared (frameworks|support)) )?path|(selected item )?identifier|data|content(s| view)?|character(s)?|click count|(command|control|option|shift) key down|context|delta (x|y|z)|key( code)?|location|pressure|unmodified characters|types|(first )?responder|playing|(allowed|selectable) identifiers|allows customization|(auto saves )?configuration|visible|image( name)?|menu form representation|tag|user(-| )defaults|associated file name|(auto|needs) display|current field editor|floating|has (resize indicator|shadow)|hides when deactivated|level|minimized (image|title)|opaque|position|release when closed|sheet|title(d)?)\b/g,
-			    css: 'color3' },
-
-			{ regex: new RegExp(this.getKeywords(specials), 'gm'), css: 'color3' },
-			{ regex: new RegExp(this.getKeywords(keywords), 'gm'), css: 'keyword' },
-			{ regex: new RegExp(this.getKeywords(ordinals), 'gm'), css: 'keyword' }
-		];
-	};
-
-	Brush.prototype = new SyntaxHighlighter.Highlighter();
-	Brush.aliases = ['applescript'];
-
-	SyntaxHighlighter.brushes.AppleScript = Brush;
-
-	// CommonJS
-	typeof(exports) != 'undefined' ? exports.Brush = Brush : null;
-})();
diff --git a/guides/assets/javascripts/syntaxhighlighter/shBrushBash.js b/guides/assets/javascripts/syntaxhighlighter/shBrushBash.js
deleted file mode 100644
index 8c296969ff..0000000000
--- a/guides/assets/javascripts/syntaxhighlighter/shBrushBash.js
+++ /dev/null
@@ -1,59 +0,0 @@
-/**
- * SyntaxHighlighter
- * http://alexgorbatchev.com/SyntaxHighlighter
- *
- * SyntaxHighlighter is donationware. If you are using it, please donate.
- * http://alexgorbatchev.com/SyntaxHighlighter/donate.html
- *
- * @version
- * 3.0.83 (July 02 2010)
- * 
- * @copyright
- * Copyright (C) 2004-2010 Alex Gorbatchev.
- *
- * @license
- * Dual licensed under the MIT and GPL licenses.
- */
-;(function()
-{
-	// CommonJS
-	typeof(require) != 'undefined' ? SyntaxHighlighter = require('shCore').SyntaxHighlighter : null;
-
-	function Brush()
-	{
-		var keywords =	'if fi then elif else for do done until while break continue case function return in eq ne ge le';
-		var commands =  'alias apropos awk basename bash bc bg builtin bzip2 cal cat cd cfdisk chgrp chmod chown chroot' +
-						'cksum clear cmp comm command cp cron crontab csplit cut date dc dd ddrescue declare df ' +
-						'diff diff3 dig dir dircolors dirname dirs du echo egrep eject enable env ethtool eval ' +
-						'exec exit expand export expr false fdformat fdisk fg fgrep file find fmt fold format ' +
-						'free fsck ftp gawk getopts grep groups gzip hash head history hostname id ifconfig ' +
-						'import install join kill less let ln local locate logname logout look lpc lpr lprint ' +
-						'lprintd lprintq lprm ls lsof make man mkdir mkfifo mkisofs mknod more mount mtools ' +
-						'mv netstat nice nl nohup nslookup open op passwd paste pathchk ping popd pr printcap ' +
-						'printenv printf ps pushd pwd quota quotacheck quotactl ram rcp read readonly renice ' +
-						'remsync rm rmdir rsync screen scp sdiff sed select seq set sftp shift shopt shutdown ' +
-						'sleep sort source split ssh strace su sudo sum symlink sync tail tar tee test time ' +
-						'times touch top traceroute trap tr true tsort tty type ulimit umask umount unalias ' +
-						'uname unexpand uniq units unset unshar useradd usermod users uuencode uudecode v vdir ' +
-						'vi watch wc whereis which who whoami Wget xargs yes'
-						;
-
-		this.regexList = [
-			{ regex: /^#!.*$/gm,											css: 'preprocessor bold' },
-			{ regex: /\/[\w-\/]+/gm,										css: 'plain' },
-			{ regex: SyntaxHighlighter.regexLib.singleLinePerlComments,		css: 'comments' },		// one line comments
-			{ regex: SyntaxHighlighter.regexLib.doubleQuotedString,			css: 'string' },		// double quoted strings
-			{ regex: SyntaxHighlighter.regexLib.singleQuotedString,			css: 'string' },		// single quoted strings
-			{ regex: new RegExp(this.getKeywords(keywords), 'gm'),			css: 'keyword' },		// keywords
-			{ regex: new RegExp(this.getKeywords(commands), 'gm'),			css: 'functions' }		// commands
-			];
-	}
-
-	Brush.prototype	= new SyntaxHighlighter.Highlighter();
-	Brush.aliases	= ['bash', 'shell'];
-
-	SyntaxHighlighter.brushes.Bash = Brush;
-
-	// CommonJS
-	typeof(exports) != 'undefined' ? exports.Brush = Brush : null;
-})();
diff --git a/guides/assets/javascripts/syntaxhighlighter/shBrushCSharp.js b/guides/assets/javascripts/syntaxhighlighter/shBrushCSharp.js
deleted file mode 100644
index 079214efe1..0000000000
--- a/guides/assets/javascripts/syntaxhighlighter/shBrushCSharp.js
+++ /dev/null
@@ -1,65 +0,0 @@
-/**
- * SyntaxHighlighter
- * http://alexgorbatchev.com/SyntaxHighlighter
- *
- * SyntaxHighlighter is donationware. If you are using it, please donate.
- * http://alexgorbatchev.com/SyntaxHighlighter/donate.html
- *
- * @version
- * 3.0.83 (July 02 2010)
- * 
- * @copyright
- * Copyright (C) 2004-2010 Alex Gorbatchev.
- *
- * @license
- * Dual licensed under the MIT and GPL licenses.
- */
-;(function()
-{
-	// CommonJS
-	typeof(require) != 'undefined' ? SyntaxHighlighter = require('shCore').SyntaxHighlighter : null;
-
-	function Brush()
-	{
-		var keywords =	'abstract as base bool break byte case catch char checked class const ' +
-						'continue decimal default delegate do double else enum event explicit ' +
-						'extern false finally fixed float for foreach get goto if implicit in int ' +
-						'interface internal is lock long namespace new null object operator out ' +
-						'override params private protected public readonly ref return sbyte sealed set ' +
-						'short sizeof stackalloc static string struct switch this throw true try ' +
-						'typeof uint ulong unchecked unsafe ushort using virtual void while';
-
-		function fixComments(match, regexInfo)
-		{
-			var css = (match[0].indexOf("///") == 0)
-				? 'color1'
-				: 'comments'
-				;
-			
-			return [new SyntaxHighlighter.Match(match[0], match.index, css)];
-		}
-
-		this.regexList = [
-			{ regex: SyntaxHighlighter.regexLib.singleLineCComments,	func : fixComments },		// one line comments
-			{ regex: SyntaxHighlighter.regexLib.multiLineCComments,		css: 'comments' },			// multiline comments
-			{ regex: /@"(?:[^"]|"")*"/g,								css: 'string' },			// @-quoted strings
-			{ regex: SyntaxHighlighter.regexLib.doubleQuotedString,		css: 'string' },			// strings
-			{ regex: SyntaxHighlighter.regexLib.singleQuotedString,		css: 'string' },			// strings
-			{ regex: /^\s*#.*/gm,										css: 'preprocessor' },		// preprocessor tags like #region and #endregion
-			{ regex: new RegExp(this.getKeywords(keywords), 'gm'),		css: 'keyword' },			// c# keyword
-			{ regex: /\bpartial(?=\s+(?:class|interface|struct)\b)/g,	css: 'keyword' },			// contextual keyword: 'partial'
-			{ regex: /\byield(?=\s+(?:return|break)\b)/g,				css: 'keyword' }			// contextual keyword: 'yield'
-			];
-		
-		this.forHtmlScript(SyntaxHighlighter.regexLib.aspScriptTags);
-	};
-
-	Brush.prototype	= new SyntaxHighlighter.Highlighter();
-	Brush.aliases	= ['c#', 'c-sharp', 'csharp'];
-
-	SyntaxHighlighter.brushes.CSharp = Brush;
-
-	// CommonJS
-	typeof(exports) != 'undefined' ? exports.Brush = Brush : null;
-})();
-
diff --git a/guides/assets/javascripts/syntaxhighlighter/shBrushColdFusion.js b/guides/assets/javascripts/syntaxhighlighter/shBrushColdFusion.js
deleted file mode 100644
index 627dbb9b76..0000000000
--- a/guides/assets/javascripts/syntaxhighlighter/shBrushColdFusion.js
+++ /dev/null
@@ -1,100 +0,0 @@
-/**
- * SyntaxHighlighter
- * http://alexgorbatchev.com/SyntaxHighlighter
- *
- * SyntaxHighlighter is donationware. If you are using it, please donate.
- * http://alexgorbatchev.com/SyntaxHighlighter/donate.html
- *
- * @version
- * 3.0.83 (July 02 2010)
- * 
- * @copyright
- * Copyright (C) 2004-2010 Alex Gorbatchev.
- *
- * @license
- * Dual licensed under the MIT and GPL licenses.
- */
-;(function()
-{
-	// CommonJS
-	typeof(require) != 'undefined' ? SyntaxHighlighter = require('shCore').SyntaxHighlighter : null;
-
-	function Brush()
-	{
-		// Contributed by Jen
-		// http://www.jensbits.com/2009/05/14/coldfusion-brush-for-syntaxhighlighter-plus
-	
-		var funcs	=	'Abs ACos AddSOAPRequestHeader AddSOAPResponseHeader AjaxLink AjaxOnLoad ArrayAppend ArrayAvg ArrayClear ArrayDeleteAt ' + 
-						'ArrayInsertAt ArrayIsDefined ArrayIsEmpty ArrayLen ArrayMax ArrayMin ArraySet ArraySort ArraySum ArraySwap ArrayToList ' + 
-						'Asc ASin Atn BinaryDecode BinaryEncode BitAnd BitMaskClear BitMaskRead BitMaskSet BitNot BitOr BitSHLN BitSHRN BitXor ' + 
-						'Ceiling CharsetDecode CharsetEncode Chr CJustify Compare CompareNoCase Cos CreateDate CreateDateTime CreateObject ' + 
-						'CreateODBCDate CreateODBCDateTime CreateODBCTime CreateTime CreateTimeSpan CreateUUID DateAdd DateCompare DateConvert ' + 
-						'DateDiff DateFormat DatePart Day DayOfWeek DayOfWeekAsString DayOfYear DaysInMonth DaysInYear DE DecimalFormat DecrementValue ' + 
-						'Decrypt DecryptBinary DeleteClientVariable DeserializeJSON DirectoryExists DollarFormat DotNetToCFType Duplicate Encrypt ' + 
-						'EncryptBinary Evaluate Exp ExpandPath FileClose FileCopy FileDelete FileExists FileIsEOF FileMove FileOpen FileRead ' + 
-						'FileReadBinary FileReadLine FileSetAccessMode FileSetAttribute FileSetLastModified FileWrite Find FindNoCase FindOneOf ' + 
-						'FirstDayOfMonth Fix FormatBaseN GenerateSecretKey GetAuthUser GetBaseTagData GetBaseTagList GetBaseTemplatePath ' + 
-						'GetClientVariablesList GetComponentMetaData GetContextRoot GetCurrentTemplatePath GetDirectoryFromPath GetEncoding ' + 
-						'GetException GetFileFromPath GetFileInfo GetFunctionList GetGatewayHelper GetHttpRequestData GetHttpTimeString ' + 
-						'GetK2ServerDocCount GetK2ServerDocCountLimit GetLocale GetLocaleDisplayName GetLocalHostIP GetMetaData GetMetricData ' + 
-						'GetPageContext GetPrinterInfo GetProfileSections GetProfileString GetReadableImageFormats GetSOAPRequest GetSOAPRequestHeader ' + 
-						'GetSOAPResponse GetSOAPResponseHeader GetTempDirectory GetTempFile GetTemplatePath GetTickCount GetTimeZoneInfo GetToken ' + 
-						'GetUserRoles GetWriteableImageFormats Hash Hour HTMLCodeFormat HTMLEditFormat IIf ImageAddBorder ImageBlur ImageClearRect ' + 
-						'ImageCopy ImageCrop ImageDrawArc ImageDrawBeveledRect ImageDrawCubicCurve ImageDrawLine ImageDrawLines ImageDrawOval ' + 
-						'ImageDrawPoint ImageDrawQuadraticCurve ImageDrawRect ImageDrawRoundRect ImageDrawText ImageFlip ImageGetBlob ImageGetBufferedImage ' + 
-						'ImageGetEXIFTag ImageGetHeight ImageGetIPTCTag ImageGetWidth ImageGrayscale ImageInfo ImageNegative ImageNew ImageOverlay ImagePaste ' + 
-						'ImageRead ImageReadBase64 ImageResize ImageRotate ImageRotateDrawingAxis ImageScaleToFit ImageSetAntialiasing ImageSetBackgroundColor ' + 
-						'ImageSetDrawingColor ImageSetDrawingStroke ImageSetDrawingTransparency ImageSharpen ImageShear ImageShearDrawingAxis ImageTranslate ' + 
-						'ImageTranslateDrawingAxis ImageWrite ImageWriteBase64 ImageXORDrawingMode IncrementValue InputBaseN Insert Int IsArray IsBinary ' + 
-						'IsBoolean IsCustomFunction IsDate IsDDX IsDebugMode IsDefined IsImage IsImageFile IsInstanceOf IsJSON IsLeapYear IsLocalHost ' + 
-						'IsNumeric IsNumericDate IsObject IsPDFFile IsPDFObject IsQuery IsSimpleValue IsSOAPRequest IsStruct IsUserInAnyRole IsUserInRole ' + 
-						'IsUserLoggedIn IsValid IsWDDX IsXML IsXmlAttribute IsXmlDoc IsXmlElem IsXmlNode IsXmlRoot JavaCast JSStringFormat LCase Left Len ' + 
-						'ListAppend ListChangeDelims ListContains ListContainsNoCase ListDeleteAt ListFind ListFindNoCase ListFirst ListGetAt ListInsertAt ' + 
-						'ListLast ListLen ListPrepend ListQualify ListRest ListSetAt ListSort ListToArray ListValueCount ListValueCountNoCase LJustify Log ' + 
-						'Log10 LSCurrencyFormat LSDateFormat LSEuroCurrencyFormat LSIsCurrency LSIsDate LSIsNumeric LSNumberFormat LSParseCurrency LSParseDateTime ' + 
-						'LSParseEuroCurrency LSParseNumber LSTimeFormat LTrim Max Mid Min Minute Month MonthAsString Now NumberFormat ParagraphFormat ParseDateTime ' + 
-						'Pi PrecisionEvaluate PreserveSingleQuotes Quarter QueryAddColumn QueryAddRow QueryConvertForGrid QueryNew QuerySetCell QuotedValueList Rand ' + 
-						'Randomize RandRange REFind REFindNoCase ReleaseComObject REMatch REMatchNoCase RemoveChars RepeatString Replace ReplaceList ReplaceNoCase ' + 
-						'REReplace REReplaceNoCase Reverse Right RJustify Round RTrim Second SendGatewayMessage SerializeJSON SetEncoding SetLocale SetProfileString ' + 
-						'SetVariable Sgn Sin Sleep SpanExcluding SpanIncluding Sqr StripCR StructAppend StructClear StructCopy StructCount StructDelete StructFind ' + 
-						'StructFindKey StructFindValue StructGet StructInsert StructIsEmpty StructKeyArray StructKeyExists StructKeyList StructKeyList StructNew ' + 
-						'StructSort StructUpdate Tan TimeFormat ToBase64 ToBinary ToScript ToString Trim UCase URLDecode URLEncodedFormat URLSessionFormat Val ' + 
-						'ValueList VerifyClient Week Wrap Wrap WriteOutput XmlChildPos XmlElemNew XmlFormat XmlGetNodeType XmlNew XmlParse XmlSearch XmlTransform ' + 
-						'XmlValidate Year YesNoFormat';
-
-		var keywords =	'cfabort cfajaximport cfajaxproxy cfapplet cfapplication cfargument cfassociate cfbreak cfcache cfcalendar ' + 
-						'cfcase cfcatch cfchart cfchartdata cfchartseries cfcol cfcollection cfcomponent cfcontent cfcookie cfdbinfo ' + 
-						'cfdefaultcase cfdirectory cfdiv cfdocument cfdocumentitem cfdocumentsection cfdump cfelse cfelseif cferror ' + 
-						'cfexchangecalendar cfexchangeconnection cfexchangecontact cfexchangefilter cfexchangemail cfexchangetask ' + 
-						'cfexecute cfexit cffeed cffile cfflush cfform cfformgroup cfformitem cfftp cffunction cfgrid cfgridcolumn ' + 
-						'cfgridrow cfgridupdate cfheader cfhtmlhead cfhttp cfhttpparam cfif cfimage cfimport cfinclude cfindex ' + 
-						'cfinput cfinsert cfinterface cfinvoke cfinvokeargument cflayout cflayoutarea cfldap cflocation cflock cflog ' + 
-						'cflogin cfloginuser cflogout cfloop cfmail cfmailparam cfmailpart cfmenu cfmenuitem cfmodule cfNTauthenticate ' + 
-						'cfobject cfobjectcache cfoutput cfparam cfpdf cfpdfform cfpdfformparam cfpdfparam cfpdfsubform cfpod cfpop ' + 
-						'cfpresentation cfpresentationslide cfpresenter cfprint cfprocessingdirective cfprocparam cfprocresult ' + 
-						'cfproperty cfquery cfqueryparam cfregistry cfreport cfreportparam cfrethrow cfreturn cfsavecontent cfschedule ' + 
-						'cfscript cfsearch cfselect cfset cfsetting cfsilent cfslider cfsprydataset cfstoredproc cfswitch cftable ' + 
-						'cftextarea cfthread cfthrow cftimer cftooltip cftrace cftransaction cftree cftreeitem cftry cfupdate cfwddx ' + 
-						'cfwindow cfxml cfzip cfzipparam';
-
-		var operators =	'all and any between cross in join like not null or outer some';
-
-		this.regexList = [
-			{ regex: new RegExp('--(.*)$', 'gm'),						css: 'comments' },  // one line and multiline comments
-			{ regex: SyntaxHighlighter.regexLib.xmlComments,			css: 'comments' },    // single quoted strings
-			{ regex: SyntaxHighlighter.regexLib.doubleQuotedString,		css: 'string' },    // double quoted strings
-			{ regex: SyntaxHighlighter.regexLib.singleQuotedString,		css: 'string' },    // single quoted strings
-			{ regex: new RegExp(this.getKeywords(funcs), 'gmi'),		css: 'functions' }, // functions
-			{ regex: new RegExp(this.getKeywords(operators), 'gmi'),	css: 'color1' },    // operators and such
-			{ regex: new RegExp(this.getKeywords(keywords), 'gmi'),		css: 'keyword' }    // keyword
-			];
-	}
-
-	Brush.prototype	= new SyntaxHighlighter.Highlighter();
-	Brush.aliases	= ['coldfusion','cf'];
-	
-	SyntaxHighlighter.brushes.ColdFusion = Brush;
-
-	// CommonJS
-	typeof(exports) != 'undefined' ? exports.Brush = Brush : null;
-})();
diff --git a/guides/assets/javascripts/syntaxhighlighter/shBrushCpp.js b/guides/assets/javascripts/syntaxhighlighter/shBrushCpp.js
deleted file mode 100644
index 9f70d3aed6..0000000000
--- a/guides/assets/javascripts/syntaxhighlighter/shBrushCpp.js
+++ /dev/null
@@ -1,97 +0,0 @@
-/**
- * SyntaxHighlighter
- * http://alexgorbatchev.com/SyntaxHighlighter
- *
- * SyntaxHighlighter is donationware. If you are using it, please donate.
- * http://alexgorbatchev.com/SyntaxHighlighter/donate.html
- *
- * @version
- * 3.0.83 (July 02 2010)
- * 
- * @copyright
- * Copyright (C) 2004-2010 Alex Gorbatchev.
- *
- * @license
- * Dual licensed under the MIT and GPL licenses.
- */
-;(function()
-{
-	// CommonJS
-	typeof(require) != 'undefined' ? SyntaxHighlighter = require('shCore').SyntaxHighlighter : null;
-
-	function Brush()
-	{
-		// Copyright 2006 Shin, YoungJin
-	
-		var datatypes =	'ATOM BOOL BOOLEAN BYTE CHAR COLORREF DWORD DWORDLONG DWORD_PTR ' +
-						'DWORD32 DWORD64 FLOAT HACCEL HALF_PTR HANDLE HBITMAP HBRUSH ' +
-						'HCOLORSPACE HCONV HCONVLIST HCURSOR HDC HDDEDATA HDESK HDROP HDWP ' +
-						'HENHMETAFILE HFILE HFONT HGDIOBJ HGLOBAL HHOOK HICON HINSTANCE HKEY ' +
-						'HKL HLOCAL HMENU HMETAFILE HMODULE HMONITOR HPALETTE HPEN HRESULT ' +
-						'HRGN HRSRC HSZ HWINSTA HWND INT INT_PTR INT32 INT64 LANGID LCID LCTYPE ' +
-						'LGRPID LONG LONGLONG LONG_PTR LONG32 LONG64 LPARAM LPBOOL LPBYTE LPCOLORREF ' +
-						'LPCSTR LPCTSTR LPCVOID LPCWSTR LPDWORD LPHANDLE LPINT LPLONG LPSTR LPTSTR ' +
-						'LPVOID LPWORD LPWSTR LRESULT PBOOL PBOOLEAN PBYTE PCHAR PCSTR PCTSTR PCWSTR ' +
-						'PDWORDLONG PDWORD_PTR PDWORD32 PDWORD64 PFLOAT PHALF_PTR PHANDLE PHKEY PINT ' +
-						'PINT_PTR PINT32 PINT64 PLCID PLONG PLONGLONG PLONG_PTR PLONG32 PLONG64 POINTER_32 ' +
-						'POINTER_64 PSHORT PSIZE_T PSSIZE_T PSTR PTBYTE PTCHAR PTSTR PUCHAR PUHALF_PTR ' +
-						'PUINT PUINT_PTR PUINT32 PUINT64 PULONG PULONGLONG PULONG_PTR PULONG32 PULONG64 ' +
-						'PUSHORT PVOID PWCHAR PWORD PWSTR SC_HANDLE SC_LOCK SERVICE_STATUS_HANDLE SHORT ' +
-						'SIZE_T SSIZE_T TBYTE TCHAR UCHAR UHALF_PTR UINT UINT_PTR UINT32 UINT64 ULONG ' +
-						'ULONGLONG ULONG_PTR ULONG32 ULONG64 USHORT USN VOID WCHAR WORD WPARAM WPARAM WPARAM ' +
-						'char bool short int __int32 __int64 __int8 __int16 long float double __wchar_t ' +
-						'clock_t _complex _dev_t _diskfree_t div_t ldiv_t _exception _EXCEPTION_POINTERS ' +
-						'FILE _finddata_t _finddatai64_t _wfinddata_t _wfinddatai64_t __finddata64_t ' +
-						'__wfinddata64_t _FPIEEE_RECORD fpos_t _HEAPINFO _HFILE lconv intptr_t ' +
-						'jmp_buf mbstate_t _off_t _onexit_t _PNH ptrdiff_t _purecall_handler ' +
-						'sig_atomic_t size_t _stat __stat64 _stati64 terminate_function ' +
-						'time_t __time64_t _timeb __timeb64 tm uintptr_t _utimbuf ' +
-						'va_list wchar_t wctrans_t wctype_t wint_t signed';
-
-		var keywords =	'break case catch class const __finally __exception __try ' +
-						'const_cast continue private public protected __declspec ' +
-						'default delete deprecated dllexport dllimport do dynamic_cast ' +
-						'else enum explicit extern if for friend goto inline ' +
-						'mutable naked namespace new noinline noreturn nothrow ' +
-						'register reinterpret_cast return selectany ' +
-						'sizeof static static_cast struct switch template this ' +
-						'thread throw true false try typedef typeid typename union ' +
-						'using uuid virtual void volatile whcar_t while';
-					
-		var functions =	'assert isalnum isalpha iscntrl isdigit isgraph islower isprint' +
-						'ispunct isspace isupper isxdigit tolower toupper errno localeconv ' +
-						'setlocale acos asin atan atan2 ceil cos cosh exp fabs floor fmod ' +
-						'frexp ldexp log log10 modf pow sin sinh sqrt tan tanh jmp_buf ' +
-						'longjmp setjmp raise signal sig_atomic_t va_arg va_end va_start ' +
-						'clearerr fclose feof ferror fflush fgetc fgetpos fgets fopen ' +
-						'fprintf fputc fputs fread freopen fscanf fseek fsetpos ftell ' +
-						'fwrite getc getchar gets perror printf putc putchar puts remove ' +
-						'rename rewind scanf setbuf setvbuf sprintf sscanf tmpfile tmpnam ' +
-						'ungetc vfprintf vprintf vsprintf abort abs atexit atof atoi atol ' +
-						'bsearch calloc div exit free getenv labs ldiv malloc mblen mbstowcs ' +
-						'mbtowc qsort rand realloc srand strtod strtol strtoul system ' +
-						'wcstombs wctomb memchr memcmp memcpy memmove memset strcat strchr ' +
-						'strcmp strcoll strcpy strcspn strerror strlen strncat strncmp ' +
-						'strncpy strpbrk strrchr strspn strstr strtok strxfrm asctime ' +
-						'clock ctime difftime gmtime localtime mktime strftime time';
-
-		this.regexList = [
-			{ regex: SyntaxHighlighter.regexLib.singleLineCComments,	css: 'comments' },			// one line comments
-			{ regex: SyntaxHighlighter.regexLib.multiLineCComments,		css: 'comments' },			// multiline comments
-			{ regex: SyntaxHighlighter.regexLib.doubleQuotedString,		css: 'string' },			// strings
-			{ regex: SyntaxHighlighter.regexLib.singleQuotedString,		css: 'string' },			// strings
-			{ regex: /^ *#.*/gm,										css: 'preprocessor' },
-			{ regex: new RegExp(this.getKeywords(datatypes), 'gm'),		css: 'color1 bold' },
-			{ regex: new RegExp(this.getKeywords(functions), 'gm'),		css: 'functions bold' },
-			{ regex: new RegExp(this.getKeywords(keywords), 'gm'),		css: 'keyword bold' }
-			];
-	};
-
-	Brush.prototype	= new SyntaxHighlighter.Highlighter();
-	Brush.aliases	= ['cpp', 'c'];
-
-	SyntaxHighlighter.brushes.Cpp = Brush;
-
-	// CommonJS
-	typeof(exports) != 'undefined' ? exports.Brush = Brush : null;
-})();
diff --git a/guides/assets/javascripts/syntaxhighlighter/shBrushCss.js b/guides/assets/javascripts/syntaxhighlighter/shBrushCss.js
deleted file mode 100644
index 4297a9a648..0000000000
--- a/guides/assets/javascripts/syntaxhighlighter/shBrushCss.js
+++ /dev/null
@@ -1,91 +0,0 @@
-/**
- * SyntaxHighlighter
- * http://alexgorbatchev.com/SyntaxHighlighter
- *
- * SyntaxHighlighter is donationware. If you are using it, please donate.
- * http://alexgorbatchev.com/SyntaxHighlighter/donate.html
- *
- * @version
- * 3.0.83 (July 02 2010)
- * 
- * @copyright
- * Copyright (C) 2004-2010 Alex Gorbatchev.
- *
- * @license
- * Dual licensed under the MIT and GPL licenses.
- */
-;(function()
-{
-	// CommonJS
-	typeof(require) != 'undefined' ? SyntaxHighlighter = require('shCore').SyntaxHighlighter : null;
-
-	function Brush()
-	{
-		function getKeywordsCSS(str)
-		{
-			return '\\b([a-z_]|)' + str.replace(/ /g, '(?=:)\\b|\\b([a-z_\\*]|\\*|)') + '(?=:)\\b';
-		};
-	
-		function getValuesCSS(str)
-		{
-			return '\\b' + str.replace(/ /g, '(?!-)(?!:)\\b|\\b()') + '\:\\b';
-		};
-
-		var keywords =	'ascent azimuth background-attachment background-color background-image background-position ' +
-						'background-repeat background baseline bbox border-collapse border-color border-spacing border-style border-top ' +
-						'border-right border-bottom border-left border-top-color border-right-color border-bottom-color border-left-color ' +
-						'border-top-style border-right-style border-bottom-style border-left-style border-top-width border-right-width ' +
-						'border-bottom-width border-left-width border-width border bottom cap-height caption-side centerline clear clip color ' +
-						'content counter-increment counter-reset cue-after cue-before cue cursor definition-src descent direction display ' +
-						'elevation empty-cells float font-size-adjust font-family font-size font-stretch font-style font-variant font-weight font ' +
-						'height left letter-spacing line-height list-style-image list-style-position list-style-type list-style margin-top ' +
-						'margin-right margin-bottom margin-left margin marker-offset marks mathline max-height max-width min-height min-width orphans ' +
-						'outline-color outline-style outline-width outline overflow padding-top padding-right padding-bottom padding-left padding page ' +
-						'page-break-after page-break-before page-break-inside pause pause-after pause-before pitch pitch-range play-during position ' +
-						'quotes right richness size slope src speak-header speak-numeral speak-punctuation speak speech-rate stemh stemv stress ' +
-						'table-layout text-align top text-decoration text-indent text-shadow text-transform unicode-bidi unicode-range units-per-em ' +
-						'vertical-align visibility voice-family volume white-space widows width widths word-spacing x-height z-index';
-
-		var values =	'above absolute all always aqua armenian attr aural auto avoid baseline behind below bidi-override black blink block blue bold bolder '+
-						'both bottom braille capitalize caption center center-left center-right circle close-quote code collapse compact condensed '+
-						'continuous counter counters crop cross crosshair cursive dashed decimal decimal-leading-zero default digits disc dotted double '+
-						'embed embossed e-resize expanded extra-condensed extra-expanded fantasy far-left far-right fast faster fixed format fuchsia '+
-						'gray green groove handheld hebrew help hidden hide high higher icon inline-table inline inset inside invert italic '+
-						'justify landscape large larger left-side left leftwards level lighter lime line-through list-item local loud lower-alpha '+
-						'lowercase lower-greek lower-latin lower-roman lower low ltr marker maroon medium message-box middle mix move narrower '+
-						'navy ne-resize no-close-quote none no-open-quote no-repeat normal nowrap n-resize nw-resize oblique olive once open-quote outset '+
-						'outside overline pointer portrait pre print projection purple red relative repeat repeat-x repeat-y rgb ridge right right-side '+
-						'rightwards rtl run-in screen scroll semi-condensed semi-expanded separate se-resize show silent silver slower slow '+
-						'small small-caps small-caption smaller soft solid speech spell-out square s-resize static status-bar sub super sw-resize '+
-						'table-caption table-cell table-column table-column-group table-footer-group table-header-group table-row table-row-group teal '+
-						'text-bottom text-top thick thin top transparent tty tv ultra-condensed ultra-expanded underline upper-alpha uppercase upper-latin '+
-						'upper-roman url visible wait white wider w-resize x-fast x-high x-large x-loud x-low x-slow x-small x-soft xx-large xx-small yellow';
-
-		var fonts =		'[mM]onospace [tT]ahoma [vV]erdana [aA]rial [hH]elvetica [sS]ans-serif [sS]erif [cC]ourier mono sans serif';
-	
-		this.regexList = [
-			{ regex: SyntaxHighlighter.regexLib.multiLineCComments,		css: 'comments' },	// multiline comments
-			{ regex: SyntaxHighlighter.regexLib.doubleQuotedString,		css: 'string' },	// double quoted strings
-			{ regex: SyntaxHighlighter.regexLib.singleQuotedString,		css: 'string' },	// single quoted strings
-			{ regex: /\#[a-fA-F0-9]{3,6}/g,								css: 'value' },		// html colors
-			{ regex: /(-?\d+)(\.\d+)?(px|em|pt|\:|\%|)/g,				css: 'value' },		// sizes
-			{ regex: /!important/g,										css: 'color3' },	// !important
-			{ regex: new RegExp(getKeywordsCSS(keywords), 'gm'),		css: 'keyword' },	// keywords
-			{ regex: new RegExp(getValuesCSS(values), 'g'),				css: 'value' },		// values
-			{ regex: new RegExp(this.getKeywords(fonts), 'g'),			css: 'color1' }		// fonts
-			];
-
-		this.forHtmlScript({ 
-			left: /(&lt;|<)\s*style.*?(&gt;|>)/gi, 
-			right: /(&lt;|<)\/\s*style\s*(&gt;|>)/gi 
-			});
-	};
-
-	Brush.prototype	= new SyntaxHighlighter.Highlighter();
-	Brush.aliases	= ['css'];
-
-	SyntaxHighlighter.brushes.CSS = Brush;
-
-	// CommonJS
-	typeof(exports) != 'undefined' ? exports.Brush = Brush : null;
-})();
diff --git a/guides/assets/javascripts/syntaxhighlighter/shBrushDelphi.js b/guides/assets/javascripts/syntaxhighlighter/shBrushDelphi.js
deleted file mode 100644
index e1060d4468..0000000000
--- a/guides/assets/javascripts/syntaxhighlighter/shBrushDelphi.js
+++ /dev/null
@@ -1,55 +0,0 @@
-/**
- * SyntaxHighlighter
- * http://alexgorbatchev.com/SyntaxHighlighter
- *
- * SyntaxHighlighter is donationware. If you are using it, please donate.
- * http://alexgorbatchev.com/SyntaxHighlighter/donate.html
- *
- * @version
- * 3.0.83 (July 02 2010)
- * 
- * @copyright
- * Copyright (C) 2004-2010 Alex Gorbatchev.
- *
- * @license
- * Dual licensed under the MIT and GPL licenses.
- */
-;(function()
-{
-	// CommonJS
-	typeof(require) != 'undefined' ? SyntaxHighlighter = require('shCore').SyntaxHighlighter : null;
-
-	function Brush()
-	{
-		var keywords =	'abs addr and ansichar ansistring array as asm begin boolean byte cardinal ' +
-						'case char class comp const constructor currency destructor div do double ' +
-						'downto else end except exports extended false file finalization finally ' +
-						'for function goto if implementation in inherited int64 initialization ' +
-						'integer interface is label library longint longword mod nil not object ' +
-						'of on or packed pansichar pansistring pchar pcurrency pdatetime pextended ' +
-						'pint64 pointer private procedure program property pshortstring pstring ' +
-						'pvariant pwidechar pwidestring protected public published raise real real48 ' +
-						'record repeat set shl shortint shortstring shr single smallint string then ' +
-						'threadvar to true try type unit until uses val var varirnt while widechar ' +
-						'widestring with word write writeln xor';
-
-		this.regexList = [
-			{ regex: /\(\*[\s\S]*?\*\)/gm,								css: 'comments' },  	// multiline comments (* *)
-			{ regex: /{(?!\$)[\s\S]*?}/gm,								css: 'comments' },  	// multiline comments { }
-			{ regex: SyntaxHighlighter.regexLib.singleLineCComments,	css: 'comments' },  	// one line
-			{ regex: SyntaxHighlighter.regexLib.singleQuotedString,		css: 'string' },		// strings
-			{ regex: /\{\$[a-zA-Z]+ .+\}/g,								css: 'color1' },		// compiler Directives and Region tags
-			{ regex: /\b[\d\.]+\b/g,									css: 'value' },			// numbers 12345
-			{ regex: /\$[a-zA-Z0-9]+\b/g,								css: 'value' },			// numbers $F5D3
-			{ regex: new RegExp(this.getKeywords(keywords), 'gmi'),		css: 'keyword' }		// keyword
-			];
-	};
-
-	Brush.prototype	= new SyntaxHighlighter.Highlighter();
-	Brush.aliases	= ['delphi', 'pascal', 'pas'];
-
-	SyntaxHighlighter.brushes.Delphi = Brush;
-
-	// CommonJS
-	typeof(exports) != 'undefined' ? exports.Brush = Brush : null;
-})();
diff --git a/guides/assets/javascripts/syntaxhighlighter/shBrushDiff.js b/guides/assets/javascripts/syntaxhighlighter/shBrushDiff.js
deleted file mode 100644
index e9b14fc580..0000000000
--- a/guides/assets/javascripts/syntaxhighlighter/shBrushDiff.js
+++ /dev/null
@@ -1,41 +0,0 @@
-/**
- * SyntaxHighlighter
- * http://alexgorbatchev.com/SyntaxHighlighter
- *
- * SyntaxHighlighter is donationware. If you are using it, please donate.
- * http://alexgorbatchev.com/SyntaxHighlighter/donate.html
- *
- * @version
- * 3.0.83 (July 02 2010)
- * 
- * @copyright
- * Copyright (C) 2004-2010 Alex Gorbatchev.
- *
- * @license
- * Dual licensed under the MIT and GPL licenses.
- */
-;(function()
-{
-	// CommonJS
-	typeof(require) != 'undefined' ? SyntaxHighlighter = require('shCore').SyntaxHighlighter : null;
-
-	function Brush()
-	{
-		this.regexList = [
-			{ regex: /^\+\+\+.*$/gm,		css: 'color2' },
-			{ regex: /^\-\-\-.*$/gm,		css: 'color2' },
-			{ regex: /^\s.*$/gm,			css: 'color1' },
-			{ regex: /^@@.*@@$/gm,			css: 'variable' },
-			{ regex: /^\+[^\+]{1}.*$/gm,	css: 'string' },
-			{ regex: /^\-[^\-]{1}.*$/gm,	css: 'comments' }
-			];
-	};
-
-	Brush.prototype	= new SyntaxHighlighter.Highlighter();
-	Brush.aliases	= ['diff', 'patch'];
-
-	SyntaxHighlighter.brushes.Diff = Brush;
-
-	// CommonJS
-	typeof(exports) != 'undefined' ? exports.Brush = Brush : null;
-})();
diff --git a/guides/assets/javascripts/syntaxhighlighter/shBrushErlang.js b/guides/assets/javascripts/syntaxhighlighter/shBrushErlang.js
deleted file mode 100644
index 6ba7d9da87..0000000000
--- a/guides/assets/javascripts/syntaxhighlighter/shBrushErlang.js
+++ /dev/null
@@ -1,52 +0,0 @@
-/**
- * SyntaxHighlighter
- * http://alexgorbatchev.com/SyntaxHighlighter
- *
- * SyntaxHighlighter is donationware. If you are using it, please donate.
- * http://alexgorbatchev.com/SyntaxHighlighter/donate.html
- *
- * @version
- * 3.0.83 (July 02 2010)
- * 
- * @copyright
- * Copyright (C) 2004-2010 Alex Gorbatchev.
- *
- * @license
- * Dual licensed under the MIT and GPL licenses.
- */
-;(function()
-{
-	// CommonJS
-	typeof(require) != 'undefined' ? SyntaxHighlighter = require('shCore').SyntaxHighlighter : null;
-
-	function Brush()
-	{
-		// Contributed by Jean-Lou Dupont
-		// http://jldupont.blogspot.com/2009/06/erlang-syntax-highlighter.html  
-
-		// According to: http://erlang.org/doc/reference_manual/introduction.html#1.5
-		var keywords = 'after and andalso band begin bnot bor bsl bsr bxor '+
-			'case catch cond div end fun if let not of or orelse '+
-			'query receive rem try when xor'+
-			// additional
-			' module export import define';
-
-		this.regexList = [
-			{ regex: new RegExp("[A-Z][A-Za-z0-9_]+", 'g'), 			css: 'constants' },
-			{ regex: new RegExp("\\%.+", 'gm'), 						css: 'comments' },
-			{ regex: new RegExp("\\?[A-Za-z0-9_]+", 'g'), 				css: 'preprocessor' },
-			{ regex: new RegExp("[a-z0-9_]+:[a-z0-9_]+", 'g'), 			css: 'functions' },
-			{ regex: SyntaxHighlighter.regexLib.doubleQuotedString,		css: 'string' },
-			{ regex: SyntaxHighlighter.regexLib.singleQuotedString,		css: 'string' },
-			{ regex: new RegExp(this.getKeywords(keywords),	'gm'),		css: 'keyword' }
-			];
-	};
-
-	Brush.prototype	= new SyntaxHighlighter.Highlighter();
-	Brush.aliases	= ['erl', 'erlang'];
-
-	SyntaxHighlighter.brushes.Erland = Brush;
-
-	// CommonJS
-	typeof(exports) != 'undefined' ? exports.Brush = Brush : null;
-})();
diff --git a/guides/assets/javascripts/syntaxhighlighter/shBrushGroovy.js b/guides/assets/javascripts/syntaxhighlighter/shBrushGroovy.js
deleted file mode 100644
index 6ec5c18521..0000000000
--- a/guides/assets/javascripts/syntaxhighlighter/shBrushGroovy.js
+++ /dev/null
@@ -1,67 +0,0 @@
-/**
- * SyntaxHighlighter
- * http://alexgorbatchev.com/SyntaxHighlighter
- *
- * SyntaxHighlighter is donationware. If you are using it, please donate.
- * http://alexgorbatchev.com/SyntaxHighlighter/donate.html
- *
- * @version
- * 3.0.83 (July 02 2010)
- * 
- * @copyright
- * Copyright (C) 2004-2010 Alex Gorbatchev.
- *
- * @license
- * Dual licensed under the MIT and GPL licenses.
- */
-;(function()
-{
-	// CommonJS
-	typeof(require) != 'undefined' ? SyntaxHighlighter = require('shCore').SyntaxHighlighter : null;
-
-	function Brush()
-	{
-		// Contributed by Andres Almiray
-		// http://jroller.com/aalmiray/entry/nice_source_code_syntax_highlighter
-
-		var keywords =	'as assert break case catch class continue def default do else extends finally ' +
-						'if in implements import instanceof interface new package property return switch ' +
-						'throw throws try while public protected private static';
-		var types    =  'void boolean byte char short int long float double';
-		var constants = 'null';
-		var methods   = 'allProperties count get size '+
-						'collect each eachProperty eachPropertyName eachWithIndex find findAll ' +
-						'findIndexOf grep inject max min reverseEach sort ' +
-						'asImmutable asSynchronized flatten intersect join pop reverse subMap toList ' +
-						'padRight padLeft contains eachMatch toCharacter toLong toUrl tokenize ' +
-						'eachFile eachFileRecurse eachB yte eachLine readBytes readLine getText ' +
-						'splitEachLine withReader append encodeBase64 decodeBase64 filterLine ' +
-						'transformChar transformLine withOutputStream withPrintWriter withStream ' +
-						'withStreams withWriter withWriterAppend write writeLine '+
-						'dump inspect invokeMethod print println step times upto use waitForOrKill '+
-						'getText';
-
-		this.regexList = [
-			{ regex: SyntaxHighlighter.regexLib.singleLineCComments,				css: 'comments' },		// one line comments
-			{ regex: SyntaxHighlighter.regexLib.multiLineCComments,					css: 'comments' },		// multiline comments
-			{ regex: SyntaxHighlighter.regexLib.doubleQuotedString,					css: 'string' },		// strings
-			{ regex: SyntaxHighlighter.regexLib.singleQuotedString,					css: 'string' },		// strings
-			{ regex: /""".*"""/g,													css: 'string' },		// GStrings
-			{ regex: new RegExp('\\b([\\d]+(\\.[\\d]+)?|0x[a-f0-9]+)\\b', 'gi'),	css: 'value' },			// numbers
-			{ regex: new RegExp(this.getKeywords(keywords), 'gm'),					css: 'keyword' },		// goovy keyword
-			{ regex: new RegExp(this.getKeywords(types), 'gm'),						css: 'color1' },		// goovy/java type
-			{ regex: new RegExp(this.getKeywords(constants), 'gm'),					css: 'constants' },		// constants
-			{ regex: new RegExp(this.getKeywords(methods), 'gm'),					css: 'functions' }		// methods
-			];
-
-		this.forHtmlScript(SyntaxHighlighter.regexLib.aspScriptTags);
-	}
-
-	Brush.prototype	= new SyntaxHighlighter.Highlighter();
-	Brush.aliases	= ['groovy'];
-
-	SyntaxHighlighter.brushes.Groovy = Brush;
-
-	// CommonJS
-	typeof(exports) != 'undefined' ? exports.Brush = Brush : null;
-})();
diff --git a/guides/assets/javascripts/syntaxhighlighter/shBrushJScript.js b/guides/assets/javascripts/syntaxhighlighter/shBrushJScript.js
deleted file mode 100644
index ff98daba16..0000000000
--- a/guides/assets/javascripts/syntaxhighlighter/shBrushJScript.js
+++ /dev/null
@@ -1,52 +0,0 @@
-/**
- * SyntaxHighlighter
- * http://alexgorbatchev.com/SyntaxHighlighter
- *
- * SyntaxHighlighter is donationware. If you are using it, please donate.
- * http://alexgorbatchev.com/SyntaxHighlighter/donate.html
- *
- * @version
- * 3.0.83 (July 02 2010)
- * 
- * @copyright
- * Copyright (C) 2004-2010 Alex Gorbatchev.
- *
- * @license
- * Dual licensed under the MIT and GPL licenses.
- */
-;(function()
-{
-	// CommonJS
-	typeof(require) != 'undefined' ? SyntaxHighlighter = require('shCore').SyntaxHighlighter : null;
-
-	function Brush()
-	{
-		var keywords =	'break case catch continue ' +
-						'default delete do else false  ' +
-						'for function if in instanceof ' +
-						'new null return super switch ' +
-						'this throw true try typeof var while with'
-						;
-
-		var r = SyntaxHighlighter.regexLib;
-		
-		this.regexList = [
-			{ regex: r.multiLineDoubleQuotedString,					css: 'string' },			// double quoted strings
-			{ regex: r.multiLineSingleQuotedString,					css: 'string' },			// single quoted strings
-			{ regex: r.singleLineCComments,							css: 'comments' },			// one line comments
-			{ regex: r.multiLineCComments,							css: 'comments' },			// multiline comments
-			{ regex: /\s*#.*/gm,									css: 'preprocessor' },		// preprocessor tags like #region and #endregion
-			{ regex: new RegExp(this.getKeywords(keywords), 'gm'),	css: 'keyword' }			// keywords
-			];
-	
-		this.forHtmlScript(r.scriptScriptTags);
-	};
-
-	Brush.prototype	= new SyntaxHighlighter.Highlighter();
-	Brush.aliases	= ['js', 'jscript', 'javascript'];
-
-	SyntaxHighlighter.brushes.JScript = Brush;
-
-	// CommonJS
-	typeof(exports) != 'undefined' ? exports.Brush = Brush : null;
-})();
diff --git a/guides/assets/javascripts/syntaxhighlighter/shBrushJava.js b/guides/assets/javascripts/syntaxhighlighter/shBrushJava.js
deleted file mode 100644
index d692fd6382..0000000000
--- a/guides/assets/javascripts/syntaxhighlighter/shBrushJava.js
+++ /dev/null
@@ -1,57 +0,0 @@
-/**
- * SyntaxHighlighter
- * http://alexgorbatchev.com/SyntaxHighlighter
- *
- * SyntaxHighlighter is donationware. If you are using it, please donate.
- * http://alexgorbatchev.com/SyntaxHighlighter/donate.html
- *
- * @version
- * 3.0.83 (July 02 2010)
- * 
- * @copyright
- * Copyright (C) 2004-2010 Alex Gorbatchev.
- *
- * @license
- * Dual licensed under the MIT and GPL licenses.
- */
-;(function()
-{
-	// CommonJS
-	typeof(require) != 'undefined' ? SyntaxHighlighter = require('shCore').SyntaxHighlighter : null;
-
-	function Brush()
-	{
-		var keywords =	'abstract assert boolean break byte case catch char class const ' +
-						'continue default do double else enum extends ' +
-						'false final finally float for goto if implements import ' +
-						'instanceof int interface long native new null ' +
-						'package private protected public return ' +
-						'short static strictfp super switch synchronized this throw throws true ' +
-						'transient try void volatile while';
-
-		this.regexList = [
-			{ regex: SyntaxHighlighter.regexLib.singleLineCComments,	css: 'comments' },		// one line comments
-			{ regex: /\/\*([^\*][\s\S]*)?\*\//gm,						css: 'comments' },	 	// multiline comments
-			{ regex: /\/\*(?!\*\/)\*[\s\S]*?\*\//gm,					css: 'preprocessor' },	// documentation comments
-			{ regex: SyntaxHighlighter.regexLib.doubleQuotedString,		css: 'string' },		// strings
-			{ regex: SyntaxHighlighter.regexLib.singleQuotedString,		css: 'string' },		// strings
-			{ regex: /\b([\d]+(\.[\d]+)?|0x[a-f0-9]+)\b/gi,				css: 'value' },			// numbers
-			{ regex: /(?!\@interface\b)\@[\$\w]+\b/g,					css: 'color1' },		// annotation @anno
-			{ regex: /\@interface\b/g,									css: 'color2' },		// @interface keyword
-			{ regex: new RegExp(this.getKeywords(keywords), 'gm'),		css: 'keyword' }		// java keyword
-			];
-
-		this.forHtmlScript({
-			left	: /(&lt;|<)%[@!=]?/g, 
-			right	: /%(&gt;|>)/g 
-		});
-	};
-
-	Brush.prototype	= new SyntaxHighlighter.Highlighter();
-	Brush.aliases	= ['java'];
-
-	SyntaxHighlighter.brushes.Java = Brush;
-
-	// CommonJS
-	typeof(exports) != 'undefined' ? exports.Brush = Brush : null;
-})();
diff --git a/guides/assets/javascripts/syntaxhighlighter/shBrushJavaFX.js b/guides/assets/javascripts/syntaxhighlighter/shBrushJavaFX.js
deleted file mode 100644
index 1a150a6ad3..0000000000
--- a/guides/assets/javascripts/syntaxhighlighter/shBrushJavaFX.js
+++ /dev/null
@@ -1,58 +0,0 @@
-/**
- * SyntaxHighlighter
- * http://alexgorbatchev.com/SyntaxHighlighter
- *
- * SyntaxHighlighter is donationware. If you are using it, please donate.
- * http://alexgorbatchev.com/SyntaxHighlighter/donate.html
- *
- * @version
- * 3.0.83 (July 02 2010)
- * 
- * @copyright
- * Copyright (C) 2004-2010 Alex Gorbatchev.
- *
- * @license
- * Dual licensed under the MIT and GPL licenses.
- */
-;(function()
-{
-	// CommonJS
-	typeof(require) != 'undefined' ? SyntaxHighlighter = require('shCore').SyntaxHighlighter : null;
-
-	function Brush()
-	{
-		// Contributed by Patrick Webster
-		// http://patrickwebster.blogspot.com/2009/04/javafx-brush-for-syntaxhighlighter.html
-		var datatypes =	'Boolean Byte Character Double Duration '
-						+ 'Float Integer Long Number Short String Void'
-						;
-
-		var keywords = 'abstract after and as assert at before bind bound break catch class '
-						+ 'continue def delete else exclusive extends false finally first for from '
-						+ 'function if import in indexof init insert instanceof into inverse last '
-						+ 'lazy mixin mod nativearray new not null on or override package postinit '
-						+ 'protected public public-init public-read replace return reverse sizeof '
-						+ 'step super then this throw true try tween typeof var where while with '
-						+ 'attribute let private readonly static trigger'
-						;
-
-		this.regexList = [
-			{ regex: SyntaxHighlighter.regexLib.singleLineCComments,	css: 'comments' },
-			{ regex: SyntaxHighlighter.regexLib.multiLineCComments,		css: 'comments' },
-			{ regex: SyntaxHighlighter.regexLib.singleQuotedString,		css: 'string' },
-			{ regex: SyntaxHighlighter.regexLib.doubleQuotedString,		css: 'string' },
-			{ regex: /(-?\.?)(\b(\d*\.?\d+|\d+\.?\d*)(e[+-]?\d+)?|0x[a-f\d]+)\b\.?/gi, css: 'color2' },	// numbers
-			{ regex: new RegExp(this.getKeywords(datatypes), 'gm'),		css: 'variable' },	// datatypes
-			{ regex: new RegExp(this.getKeywords(keywords), 'gm'),		css: 'keyword' }
-		];
-		this.forHtmlScript(SyntaxHighlighter.regexLib.aspScriptTags);
-	};
-
-	Brush.prototype	= new SyntaxHighlighter.Highlighter();
-	Brush.aliases	= ['jfx', 'javafx'];
-
-	SyntaxHighlighter.brushes.JavaFX = Brush;
-
-	// CommonJS
-	typeof(exports) != 'undefined' ? exports.Brush = Brush : null;
-})();
diff --git a/guides/assets/javascripts/syntaxhighlighter/shBrushPerl.js b/guides/assets/javascripts/syntaxhighlighter/shBrushPerl.js
deleted file mode 100644
index d94a2e0ec5..0000000000
--- a/guides/assets/javascripts/syntaxhighlighter/shBrushPerl.js
+++ /dev/null
@@ -1,72 +0,0 @@
-/**
- * SyntaxHighlighter
- * http://alexgorbatchev.com/SyntaxHighlighter
- *
- * SyntaxHighlighter is donationware. If you are using it, please donate.
- * http://alexgorbatchev.com/SyntaxHighlighter/donate.html
- *
- * @version
- * 3.0.83 (July 02 2010)
- * 
- * @copyright
- * Copyright (C) 2004-2010 Alex Gorbatchev.
- *
- * @license
- * Dual licensed under the MIT and GPL licenses.
- */
-;(function()
-{
-	// CommonJS
-	typeof(require) != 'undefined' ? SyntaxHighlighter = require('shCore').SyntaxHighlighter : null;
-
-	function Brush()
-	{
-		// Contributed by David Simmons-Duffin and Marty Kube
-	
-		var funcs = 
-			'abs accept alarm atan2 bind binmode chdir chmod chomp chop chown chr ' + 
-			'chroot close closedir connect cos crypt defined delete each endgrent ' + 
-			'endhostent endnetent endprotoent endpwent endservent eof exec exists ' + 
-			'exp fcntl fileno flock fork format formline getc getgrent getgrgid ' + 
-			'getgrnam gethostbyaddr gethostbyname gethostent getlogin getnetbyaddr ' + 
-			'getnetbyname getnetent getpeername getpgrp getppid getpriority ' + 
-			'getprotobyname getprotobynumber getprotoent getpwent getpwnam getpwuid ' + 
-			'getservbyname getservbyport getservent getsockname getsockopt glob ' + 
-			'gmtime grep hex index int ioctl join keys kill lc lcfirst length link ' + 
-			'listen localtime lock log lstat map mkdir msgctl msgget msgrcv msgsnd ' + 
-			'oct open opendir ord pack pipe pop pos print printf prototype push ' + 
-			'quotemeta rand read readdir readline readlink readpipe recv rename ' + 
-			'reset reverse rewinddir rindex rmdir scalar seek seekdir select semctl ' + 
-			'semget semop send setgrent sethostent setnetent setpgrp setpriority ' + 
-			'setprotoent setpwent setservent setsockopt shift shmctl shmget shmread ' + 
-			'shmwrite shutdown sin sleep socket socketpair sort splice split sprintf ' + 
-			'sqrt srand stat study substr symlink syscall sysopen sysread sysseek ' + 
-			'system syswrite tell telldir time times tr truncate uc ucfirst umask ' + 
-			'undef unlink unpack unshift utime values vec wait waitpid warn write';
-    
-		var keywords =  
-			'bless caller continue dbmclose dbmopen die do dump else elsif eval exit ' +
-			'for foreach goto if import last local my next no our package redo ref ' + 
-			'require return sub tie tied unless untie until use wantarray while';
-    
-		this.regexList = [
-			{ regex: new RegExp('#[^!].*$', 'gm'),					css: 'comments' },
-			{ regex: new RegExp('^\\s*#!.*$', 'gm'),				css: 'preprocessor' }, // shebang
-			{ regex: SyntaxHighlighter.regexLib.doubleQuotedString,	css: 'string' },
-			{ regex: SyntaxHighlighter.regexLib.singleQuotedString,	css: 'string' },
-			{ regex: new RegExp('(\\$|@|%)\\w+', 'g'),				css: 'variable' },
-			{ regex: new RegExp(this.getKeywords(funcs), 'gmi'),	css: 'functions' },
-			{ regex: new RegExp(this.getKeywords(keywords), 'gm'),	css: 'keyword' }
-		    ];
-
-		this.forHtmlScript(SyntaxHighlighter.regexLib.phpScriptTags);
-	}
-
-	Brush.prototype	= new SyntaxHighlighter.Highlighter();
-	Brush.aliases		= ['perl', 'Perl', 'pl'];
-
-	SyntaxHighlighter.brushes.Perl = Brush;
-
-	// CommonJS
-	typeof(exports) != 'undefined' ? exports.Brush = Brush : null;
-})();
diff --git a/guides/assets/javascripts/syntaxhighlighter/shBrushPhp.js b/guides/assets/javascripts/syntaxhighlighter/shBrushPhp.js
deleted file mode 100644
index 95e6e4325b..0000000000
--- a/guides/assets/javascripts/syntaxhighlighter/shBrushPhp.js
+++ /dev/null
@@ -1,88 +0,0 @@
-/**
- * SyntaxHighlighter
- * http://alexgorbatchev.com/SyntaxHighlighter
- *
- * SyntaxHighlighter is donationware. If you are using it, please donate.
- * http://alexgorbatchev.com/SyntaxHighlighter/donate.html
- *
- * @version
- * 3.0.83 (July 02 2010)
- * 
- * @copyright
- * Copyright (C) 2004-2010 Alex Gorbatchev.
- *
- * @license
- * Dual licensed under the MIT and GPL licenses.
- */
-;(function()
-{
-	// CommonJS
-	typeof(require) != 'undefined' ? SyntaxHighlighter = require('shCore').SyntaxHighlighter : null;
-
-	function Brush()
-	{
-		var funcs	=	'abs acos acosh addcslashes addslashes ' +
-						'array_change_key_case array_chunk array_combine array_count_values array_diff '+
-						'array_diff_assoc array_diff_key array_diff_uassoc array_diff_ukey array_fill '+
-						'array_filter array_flip array_intersect array_intersect_assoc array_intersect_key '+
-						'array_intersect_uassoc array_intersect_ukey array_key_exists array_keys array_map '+
-						'array_merge array_merge_recursive array_multisort array_pad array_pop array_product '+
-						'array_push array_rand array_reduce array_reverse array_search array_shift '+
-						'array_slice array_splice array_sum array_udiff array_udiff_assoc '+
-						'array_udiff_uassoc array_uintersect array_uintersect_assoc '+
-						'array_uintersect_uassoc array_unique array_unshift array_values array_walk '+
-						'array_walk_recursive atan atan2 atanh base64_decode base64_encode base_convert '+
-						'basename bcadd bccomp bcdiv bcmod bcmul bindec bindtextdomain bzclose bzcompress '+
-						'bzdecompress bzerrno bzerror bzerrstr bzflush bzopen bzread bzwrite ceil chdir '+
-						'checkdate checkdnsrr chgrp chmod chop chown chr chroot chunk_split class_exists '+
-						'closedir closelog copy cos cosh count count_chars date decbin dechex decoct '+
-						'deg2rad delete ebcdic2ascii echo empty end ereg ereg_replace eregi eregi_replace error_log '+
-						'error_reporting escapeshellarg escapeshellcmd eval exec exit exp explode extension_loaded '+
-						'feof fflush fgetc fgetcsv fgets fgetss file_exists file_get_contents file_put_contents '+
-						'fileatime filectime filegroup fileinode filemtime fileowner fileperms filesize filetype '+
-						'floatval flock floor flush fmod fnmatch fopen fpassthru fprintf fputcsv fputs fread fscanf '+
-						'fseek fsockopen fstat ftell ftok getallheaders getcwd getdate getenv gethostbyaddr gethostbyname '+
-						'gethostbynamel getimagesize getlastmod getmxrr getmygid getmyinode getmypid getmyuid getopt '+
-						'getprotobyname getprotobynumber getrandmax getrusage getservbyname getservbyport gettext '+
-						'gettimeofday gettype glob gmdate gmmktime ini_alter ini_get ini_get_all ini_restore ini_set '+
-						'interface_exists intval ip2long is_a is_array is_bool is_callable is_dir is_double '+
-						'is_executable is_file is_finite is_float is_infinite is_int is_integer is_link is_long '+
-						'is_nan is_null is_numeric is_object is_readable is_real is_resource is_scalar is_soap_fault '+
-						'is_string is_subclass_of is_uploaded_file is_writable is_writeable mkdir mktime nl2br '+
-						'parse_ini_file parse_str parse_url passthru pathinfo print readlink realpath rewind rewinddir rmdir '+
-						'round str_ireplace str_pad str_repeat str_replace str_rot13 str_shuffle str_split '+
-						'str_word_count strcasecmp strchr strcmp strcoll strcspn strftime strip_tags stripcslashes '+
-						'stripos stripslashes stristr strlen strnatcasecmp strnatcmp strncasecmp strncmp strpbrk '+
-						'strpos strptime strrchr strrev strripos strrpos strspn strstr strtok strtolower strtotime '+
-						'strtoupper strtr strval substr substr_compare';
-
-		var keywords =	'abstract and array as break case catch cfunction class clone const continue declare default die do ' +
-						'else elseif enddeclare endfor endforeach endif endswitch endwhile extends final for foreach ' +
-						'function include include_once global goto if implements interface instanceof namespace new ' +
-						'old_function or private protected public return require require_once static switch ' +
-						'throw try use var while xor ';
-		
-		var constants	= '__FILE__ __LINE__ __METHOD__ __FUNCTION__ __CLASS__';
-
-		this.regexList = [
-			{ regex: SyntaxHighlighter.regexLib.singleLineCComments,	css: 'comments' },			// one line comments
-			{ regex: SyntaxHighlighter.regexLib.multiLineCComments,		css: 'comments' },			// multiline comments
-			{ regex: SyntaxHighlighter.regexLib.doubleQuotedString,		css: 'string' },			// double quoted strings
-			{ regex: SyntaxHighlighter.regexLib.singleQuotedString,		css: 'string' },			// single quoted strings
-			{ regex: /\$\w+/g,											css: 'variable' },			// variables
-			{ regex: new RegExp(this.getKeywords(funcs), 'gmi'),		css: 'functions' },			// common functions
-			{ regex: new RegExp(this.getKeywords(constants), 'gmi'),	css: 'constants' },			// constants
-			{ regex: new RegExp(this.getKeywords(keywords), 'gm'),		css: 'keyword' }			// keyword
-			];
-
-		this.forHtmlScript(SyntaxHighlighter.regexLib.phpScriptTags);
-	};
-
-	Brush.prototype	= new SyntaxHighlighter.Highlighter();
-	Brush.aliases	= ['php'];
-
-	SyntaxHighlighter.brushes.Php = Brush;
-
-	// CommonJS
-	typeof(exports) != 'undefined' ? exports.Brush = Brush : null;
-})();
diff --git a/guides/assets/javascripts/syntaxhighlighter/shBrushPlain.js b/guides/assets/javascripts/syntaxhighlighter/shBrushPlain.js
deleted file mode 100644
index 9f7d9e90c3..0000000000
--- a/guides/assets/javascripts/syntaxhighlighter/shBrushPlain.js
+++ /dev/null
@@ -1,33 +0,0 @@
-/**
- * SyntaxHighlighter
- * http://alexgorbatchev.com/SyntaxHighlighter
- *
- * SyntaxHighlighter is donationware. If you are using it, please donate.
- * http://alexgorbatchev.com/SyntaxHighlighter/donate.html
- *
- * @version
- * 3.0.83 (July 02 2010)
- * 
- * @copyright
- * Copyright (C) 2004-2010 Alex Gorbatchev.
- *
- * @license
- * Dual licensed under the MIT and GPL licenses.
- */
-;(function()
-{
-	// CommonJS
-	typeof(require) != 'undefined' ? SyntaxHighlighter = require('shCore').SyntaxHighlighter : null;
-
-	function Brush()
-	{
-	};
-
-	Brush.prototype	= new SyntaxHighlighter.Highlighter();
-	Brush.aliases	= ['text', 'plain'];
-
-	SyntaxHighlighter.brushes.Plain = Brush;
-
-	// CommonJS
-	typeof(exports) != 'undefined' ? exports.Brush = Brush : null;
-})();
diff --git a/guides/assets/javascripts/syntaxhighlighter/shBrushPowerShell.js b/guides/assets/javascripts/syntaxhighlighter/shBrushPowerShell.js
deleted file mode 100644
index 0be1752968..0000000000
--- a/guides/assets/javascripts/syntaxhighlighter/shBrushPowerShell.js
+++ /dev/null
@@ -1,74 +0,0 @@
-/**
- * SyntaxHighlighter
- * http://alexgorbatchev.com/SyntaxHighlighter
- *
- * SyntaxHighlighter is donationware. If you are using it, please donate.
- * http://alexgorbatchev.com/SyntaxHighlighter/donate.html
- *
- * @version
- * 3.0.83 (July 02 2010)
- * 
- * @copyright
- * Copyright (C) 2004-2010 Alex Gorbatchev.
- *
- * @license
- * Dual licensed under the MIT and GPL licenses.
- */
-;(function()
-{
-	// CommonJS
-	typeof(require) != 'undefined' ? SyntaxHighlighter = require('shCore').SyntaxHighlighter : null;
-
-	function Brush()
-	{
-		// Contributes by B.v.Zanten, Getronics
-		// http://confluence.atlassian.com/display/CONFEXT/New+Code+Macro
-
-		var keywords = 'Add-Content Add-History Add-Member Add-PSSnapin Clear(-Content)? Clear-Item ' +
-					'Clear-ItemProperty Clear-Variable Compare-Object ConvertFrom-SecureString Convert-Path ' +
-					'ConvertTo-Html ConvertTo-SecureString Copy(-Item)? Copy-ItemProperty Export-Alias ' +
-					'Export-Clixml Export-Console Export-Csv ForEach(-Object)? Format-Custom Format-List ' +
-					'Format-Table Format-Wide Get-Acl Get-Alias Get-AuthenticodeSignature Get-ChildItem Get-Command ' +
-					'Get-Content Get-Credential Get-Culture Get-Date Get-EventLog Get-ExecutionPolicy ' +
-					'Get-Help Get-History Get-Host Get-Item Get-ItemProperty Get-Location Get-Member ' +
-					'Get-PfxCertificate Get-Process Get-PSDrive Get-PSProvider Get-PSSnapin Get-Service ' +
-					'Get-TraceSource Get-UICulture Get-Unique Get-Variable Get-WmiObject Group-Object ' +
-					'Import-Alias Import-Clixml Import-Csv Invoke-Expression Invoke-History Invoke-Item ' +
-					'Join-Path Measure-Command Measure-Object Move(-Item)? Move-ItemProperty New-Alias ' +
-					'New-Item New-ItemProperty New-Object New-PSDrive New-Service New-TimeSpan ' +
-					'New-Variable Out-Default Out-File Out-Host Out-Null Out-Printer Out-String Pop-Location ' +
-					'Push-Location Read-Host Remove-Item Remove-ItemProperty Remove-PSDrive Remove-PSSnapin ' +
-					'Remove-Variable Rename-Item Rename-ItemProperty Resolve-Path Restart-Service Resume-Service ' +
-					'Select-Object Select-String Set-Acl Set-Alias Set-AuthenticodeSignature Set-Content ' +
-					'Set-Date Set-ExecutionPolicy Set-Item Set-ItemProperty Set-Location Set-PSDebug ' +
-					'Set-Service Set-TraceSource Set(-Variable)? Sort-Object Split-Path Start-Service ' +
-					'Start-Sleep Start-Transcript Stop-Process Stop-Service Stop-Transcript Suspend-Service ' +
-					'Tee-Object Test-Path Trace-Command Update-FormatData Update-TypeData Where(-Object)? ' +
-					'Write-Debug Write-Error Write(-Host)? Write-Output Write-Progress Write-Verbose Write-Warning';
-		var alias = 'ac asnp clc cli clp clv cpi cpp cvpa diff epal epcsv fc fl ' +
-					'ft fw gal gc gci gcm gdr ghy gi gl gm gp gps group gsv ' +
-					'gsnp gu gv gwmi iex ihy ii ipal ipcsv mi mp nal ndr ni nv oh rdr ' +
-					'ri rni rnp rp rsnp rv rvpa sal sasv sc select si sl sleep sort sp ' +
-					'spps spsv sv tee cat cd cp h history kill lp ls ' +
-					'mount mv popd ps pushd pwd r rm rmdir echo cls chdir del dir ' +
-					'erase rd ren type % \\?';
-
-		this.regexList = [
-			{ regex: /#.*$/gm,										css: 'comments' },  // one line comments
-			{ regex: /\$[a-zA-Z0-9]+\b/g,							css: 'value'   },   // variables $Computer1
-			{ regex: /\-[a-zA-Z]+\b/g,								css: 'keyword' },   // Operators    -not  -and  -eq
-			{ regex: SyntaxHighlighter.regexLib.doubleQuotedString,	css: 'string' },    // strings
-			{ regex: SyntaxHighlighter.regexLib.singleQuotedString,	css: 'string' },    // strings
-			{ regex: new RegExp(this.getKeywords(keywords), 'gmi'),	css: 'keyword' },
-			{ regex: new RegExp(this.getKeywords(alias), 'gmi'),	css: 'keyword' }
-		];
-	};
-
-	Brush.prototype	= new SyntaxHighlighter.Highlighter();
-	Brush.aliases	= ['powershell', 'ps'];
-
-	SyntaxHighlighter.brushes.PowerShell = Brush;
-
-	// CommonJS
-	typeof(exports) != 'undefined' ? exports.Brush = Brush : null;
-})();
diff --git a/guides/assets/javascripts/syntaxhighlighter/shBrushPython.js b/guides/assets/javascripts/syntaxhighlighter/shBrushPython.js
deleted file mode 100644
index ce77462975..0000000000
--- a/guides/assets/javascripts/syntaxhighlighter/shBrushPython.js
+++ /dev/null
@@ -1,64 +0,0 @@
-/**
- * SyntaxHighlighter
- * http://alexgorbatchev.com/SyntaxHighlighter
- *
- * SyntaxHighlighter is donationware. If you are using it, please donate.
- * http://alexgorbatchev.com/SyntaxHighlighter/donate.html
- *
- * @version
- * 3.0.83 (July 02 2010)
- * 
- * @copyright
- * Copyright (C) 2004-2010 Alex Gorbatchev.
- *
- * @license
- * Dual licensed under the MIT and GPL licenses.
- */
-;(function()
-{
-	// CommonJS
-	typeof(require) != 'undefined' ? SyntaxHighlighter = require('shCore').SyntaxHighlighter : null;
-
-	function Brush()
-	{
-		// Contributed by Gheorghe Milas and Ahmad Sherif
-	
-		var keywords =  'and assert break class continue def del elif else ' +
-						'except exec finally for from global if import in is ' +
-						'lambda not or pass print raise return try yield while';
-
-		var funcs = '__import__ abs all any apply basestring bin bool buffer callable ' +
-					'chr classmethod cmp coerce compile complex delattr dict dir ' +
-					'divmod enumerate eval execfile file filter float format frozenset ' +
-					'getattr globals hasattr hash help hex id input int intern ' +
-					'isinstance issubclass iter len list locals long map max min next ' +
-					'object oct open ord pow print property range raw_input reduce ' +
-					'reload repr reversed round set setattr slice sorted staticmethod ' +
-					'str sum super tuple type type unichr unicode vars xrange zip';
-
-		var special =  'None True False self cls class_';
-
-		this.regexList = [
-				{ regex: SyntaxHighlighter.regexLib.singleLinePerlComments, css: 'comments' },
-				{ regex: /^\s*@\w+/gm, 										css: 'decorator' },
-				{ regex: /(['\"]{3})([^\1])*?\1/gm, 						css: 'comments' },
-				{ regex: /"(?!")(?:\.|\\\"|[^\""\n])*"/gm, 					css: 'string' },
-				{ regex: /'(?!')(?:\.|(\\\')|[^\''\n])*'/gm, 				css: 'string' },
-				{ regex: /\+|\-|\*|\/|\%|=|==/gm, 							css: 'keyword' },
-				{ regex: /\b\d+\.?\w*/g, 									css: 'value' },
-				{ regex: new RegExp(this.getKeywords(funcs), 'gmi'),		css: 'functions' },
-				{ regex: new RegExp(this.getKeywords(keywords), 'gm'), 		css: 'keyword' },
-				{ regex: new RegExp(this.getKeywords(special), 'gm'), 		css: 'color1' }
-				];
-			
-		this.forHtmlScript(SyntaxHighlighter.regexLib.aspScriptTags);
-	};
-
-	Brush.prototype	= new SyntaxHighlighter.Highlighter();
-	Brush.aliases	= ['py', 'python'];
-
-	SyntaxHighlighter.brushes.Python = Brush;
-
-	// CommonJS
-	typeof(exports) != 'undefined' ? exports.Brush = Brush : null;
-})();
diff --git a/guides/assets/javascripts/syntaxhighlighter/shBrushRuby.js b/guides/assets/javascripts/syntaxhighlighter/shBrushRuby.js
deleted file mode 100644
index ff82130a7a..0000000000
--- a/guides/assets/javascripts/syntaxhighlighter/shBrushRuby.js
+++ /dev/null
@@ -1,55 +0,0 @@
-/**
- * SyntaxHighlighter
- * http://alexgorbatchev.com/SyntaxHighlighter
- *
- * SyntaxHighlighter is donationware. If you are using it, please donate.
- * http://alexgorbatchev.com/SyntaxHighlighter/donate.html
- *
- * @version
- * 3.0.83 (July 02 2010)
- * 
- * @copyright
- * Copyright (C) 2004-2010 Alex Gorbatchev.
- *
- * @license
- * Dual licensed under the MIT and GPL licenses.
- */
-;(function()
-{
-	// CommonJS
-	typeof(require) != 'undefined' ? SyntaxHighlighter = require('shCore').SyntaxHighlighter : null;
-
-	function Brush()
-	{
-		// Contributed by Erik Peterson.
-	
-		var keywords =	'alias and BEGIN begin break case class def define_method defined do each else elsif ' +
-						'END end ensure false for if in module new next nil not or raise redo rescue retry return ' +
-						'self super then throw true undef unless until when while yield';
-
-		var builtins =	'Array Bignum Binding Class Continuation Dir Exception FalseClass File::Stat File Fixnum Fload ' +
-						'Hash Integer IO MatchData Method Module NilClass Numeric Object Proc Range Regexp String Struct::TMS Symbol ' +
-						'ThreadGroup Thread Time TrueClass';
-
-		this.regexList = [
-			{ regex: SyntaxHighlighter.regexLib.singleLinePerlComments,	css: 'comments' },		// one line comments
-			{ regex: SyntaxHighlighter.regexLib.doubleQuotedString,		css: 'string' },		// double quoted strings
-			{ regex: SyntaxHighlighter.regexLib.singleQuotedString,		css: 'string' },		// single quoted strings
-			{ regex: /\b[A-Z0-9_]+\b/g,									css: 'constants' },		// constants
-			{ regex: /:[a-z][A-Za-z0-9_]*/g,							css: 'color2' },		// symbols
-			{ regex: /(\$|@@|@)\w+/g,									css: 'variable bold' },	// $global, @instance, and @@class variables
-			{ regex: new RegExp(this.getKeywords(keywords), 'gm'),		css: 'keyword' },		// keywords
-			{ regex: new RegExp(this.getKeywords(builtins), 'gm'),		css: 'color1' }			// builtins
-			];
-
-		this.forHtmlScript(SyntaxHighlighter.regexLib.aspScriptTags);
-	};
-
-	Brush.prototype	= new SyntaxHighlighter.Highlighter();
-	Brush.aliases	= ['ruby', 'rails', 'ror', 'rb'];
-
-	SyntaxHighlighter.brushes.Ruby = Brush;
-
-	// CommonJS
-	typeof(exports) != 'undefined' ? exports.Brush = Brush : null;
-})();
diff --git a/guides/assets/javascripts/syntaxhighlighter/shBrushSass.js b/guides/assets/javascripts/syntaxhighlighter/shBrushSass.js
deleted file mode 100644
index aa04da0996..0000000000
--- a/guides/assets/javascripts/syntaxhighlighter/shBrushSass.js
+++ /dev/null
@@ -1,94 +0,0 @@
-/**
- * SyntaxHighlighter
- * http://alexgorbatchev.com/SyntaxHighlighter
- *
- * SyntaxHighlighter is donationware. If you are using it, please donate.
- * http://alexgorbatchev.com/SyntaxHighlighter/donate.html
- *
- * @version
- * 3.0.83 (July 02 2010)
- * 
- * @copyright
- * Copyright (C) 2004-2010 Alex Gorbatchev.
- *
- * @license
- * Dual licensed under the MIT and GPL licenses.
- */
-;(function()
-{
-	// CommonJS
-	typeof(require) != 'undefined' ? SyntaxHighlighter = require('shCore').SyntaxHighlighter : null;
-
-	function Brush()
-	{
-		function getKeywordsCSS(str)
-		{
-			return '\\b([a-z_]|)' + str.replace(/ /g, '(?=:)\\b|\\b([a-z_\\*]|\\*|)') + '(?=:)\\b';
-		};
-	
-		function getValuesCSS(str)
-		{
-			return '\\b' + str.replace(/ /g, '(?!-)(?!:)\\b|\\b()') + '\:\\b';
-		};
-
-		var keywords =	'ascent azimuth background-attachment background-color background-image background-position ' +
-						'background-repeat background baseline bbox border-collapse border-color border-spacing border-style border-top ' +
-						'border-right border-bottom border-left border-top-color border-right-color border-bottom-color border-left-color ' +
-						'border-top-style border-right-style border-bottom-style border-left-style border-top-width border-right-width ' +
-						'border-bottom-width border-left-width border-width border bottom cap-height caption-side centerline clear clip color ' +
-						'content counter-increment counter-reset cue-after cue-before cue cursor definition-src descent direction display ' +
-						'elevation empty-cells float font-size-adjust font-family font-size font-stretch font-style font-variant font-weight font ' +
-						'height left letter-spacing line-height list-style-image list-style-position list-style-type list-style margin-top ' +
-						'margin-right margin-bottom margin-left margin marker-offset marks mathline max-height max-width min-height min-width orphans ' +
-						'outline-color outline-style outline-width outline overflow padding-top padding-right padding-bottom padding-left padding page ' +
-						'page-break-after page-break-before page-break-inside pause pause-after pause-before pitch pitch-range play-during position ' +
-						'quotes right richness size slope src speak-header speak-numeral speak-punctuation speak speech-rate stemh stemv stress ' +
-						'table-layout text-align top text-decoration text-indent text-shadow text-transform unicode-bidi unicode-range units-per-em ' +
-						'vertical-align visibility voice-family volume white-space widows width widths word-spacing x-height z-index';
-		
-		var values =	'above absolute all always aqua armenian attr aural auto avoid baseline behind below bidi-override black blink block blue bold bolder '+
-						'both bottom braille capitalize caption center center-left center-right circle close-quote code collapse compact condensed '+
-						'continuous counter counters crop cross crosshair cursive dashed decimal decimal-leading-zero digits disc dotted double '+
-						'embed embossed e-resize expanded extra-condensed extra-expanded fantasy far-left far-right fast faster fixed format fuchsia '+
-						'gray green groove handheld hebrew help hidden hide high higher icon inline-table inline inset inside invert italic '+
-						'justify landscape large larger left-side left leftwards level lighter lime line-through list-item local loud lower-alpha '+
-						'lowercase lower-greek lower-latin lower-roman lower low ltr marker maroon medium message-box middle mix move narrower '+
-						'navy ne-resize no-close-quote none no-open-quote no-repeat normal nowrap n-resize nw-resize oblique olive once open-quote outset '+
-						'outside overline pointer portrait pre print projection purple red relative repeat repeat-x repeat-y rgb ridge right right-side '+
-						'rightwards rtl run-in screen scroll semi-condensed semi-expanded separate se-resize show silent silver slower slow '+
-						'small small-caps small-caption smaller soft solid speech spell-out square s-resize static status-bar sub super sw-resize '+
-						'table-caption table-cell table-column table-column-group table-footer-group table-header-group table-row table-row-group teal '+
-						'text-bottom text-top thick thin top transparent tty tv ultra-condensed ultra-expanded underline upper-alpha uppercase upper-latin '+
-						'upper-roman url visible wait white wider w-resize x-fast x-high x-large x-loud x-low x-slow x-small x-soft xx-large xx-small yellow';
-		
-		var fonts =		'[mM]onospace [tT]ahoma [vV]erdana [aA]rial [hH]elvetica [sS]ans-serif [sS]erif [cC]ourier mono sans serif';
-		
-		var statements		= '!important !default';
-		var preprocessor	= '@import @extend @debug @warn @if @for @while @mixin @include';
-		
-		var r = SyntaxHighlighter.regexLib;
-		
-		this.regexList = [
-			{ regex: r.multiLineCComments,								css: 'comments' },		// multiline comments
-			{ regex: r.singleLineCComments,								css: 'comments' },		// singleline comments
-			{ regex: r.doubleQuotedString,								css: 'string' },		// double quoted strings
-			{ regex: r.singleQuotedString,								css: 'string' },		// single quoted strings
-			{ regex: /\#[a-fA-F0-9]{3,6}/g,								css: 'value' },			// html colors
-			{ regex: /\b(-?\d+)(\.\d+)?(px|em|pt|\:|\%|)\b/g,			css: 'value' },			// sizes
-			{ regex: /\$\w+/g,											css: 'variable' },		// variables
-			{ regex: new RegExp(this.getKeywords(statements), 'g'),		css: 'color3' },		// statements
-			{ regex: new RegExp(this.getKeywords(preprocessor), 'g'),	css: 'preprocessor' },	// preprocessor
-			{ regex: new RegExp(getKeywordsCSS(keywords), 'gm'),		css: 'keyword' },		// keywords
-			{ regex: new RegExp(getValuesCSS(values), 'g'),				css: 'value' },			// values
-			{ regex: new RegExp(this.getKeywords(fonts), 'g'),			css: 'color1' }			// fonts
-			];
-	};
-
-	Brush.prototype	= new SyntaxHighlighter.Highlighter();
-	Brush.aliases	= ['sass', 'scss'];
-
-	SyntaxHighlighter.brushes.Sass = Brush;
-
-	// CommonJS
-	typeof(exports) != 'undefined' ? exports.Brush = Brush : null;
-})();
diff --git a/guides/assets/javascripts/syntaxhighlighter/shBrushScala.js b/guides/assets/javascripts/syntaxhighlighter/shBrushScala.js
deleted file mode 100644
index 4b0b6f04d2..0000000000
--- a/guides/assets/javascripts/syntaxhighlighter/shBrushScala.js
+++ /dev/null
@@ -1,51 +0,0 @@
-/**
- * SyntaxHighlighter
- * http://alexgorbatchev.com/SyntaxHighlighter
- *
- * SyntaxHighlighter is donationware. If you are using it, please donate.
- * http://alexgorbatchev.com/SyntaxHighlighter/donate.html
- *
- * @version
- * 3.0.83 (July 02 2010)
- * 
- * @copyright
- * Copyright (C) 2004-2010 Alex Gorbatchev.
- *
- * @license
- * Dual licensed under the MIT and GPL licenses.
- */
-;(function()
-{
-	// CommonJS
-	typeof(require) != 'undefined' ? SyntaxHighlighter = require('shCore').SyntaxHighlighter : null;
-
-	function Brush()
-	{
-		// Contributed by Yegor Jbanov and David Bernard.
-	
-		var keywords =	'val sealed case def true trait implicit forSome import match object null finally super ' +
-						'override try lazy for var catch throw type extends class while with new final yield abstract ' +
-						'else do if return protected private this package false';
-
-		var keyops =	'[_:=><%#@]+';
-
-		this.regexList = [
-			{ regex: SyntaxHighlighter.regexLib.singleLineCComments,			css: 'comments' },	// one line comments
-			{ regex: SyntaxHighlighter.regexLib.multiLineCComments,				css: 'comments' },	// multiline comments
-			{ regex: SyntaxHighlighter.regexLib.multiLineSingleQuotedString,	css: 'string' },	// multi-line strings
-			{ regex: SyntaxHighlighter.regexLib.multiLineDoubleQuotedString,    css: 'string' },	// double-quoted string
-			{ regex: SyntaxHighlighter.regexLib.singleQuotedString,				css: 'string' },	// strings
-			{ regex: /0x[a-f0-9]+|\d+(\.\d+)?/gi,								css: 'value' },		// numbers
-			{ regex: new RegExp(this.getKeywords(keywords), 'gm'),				css: 'keyword' },	// keywords
-			{ regex: new RegExp(keyops, 'gm'),									css: 'keyword' }	// scala keyword
-			];
-	}
-
-	Brush.prototype	= new SyntaxHighlighter.Highlighter();
-	Brush.aliases	= ['scala'];
-
-	SyntaxHighlighter.brushes.Scala = Brush;
-
-	// CommonJS
-	typeof(exports) != 'undefined' ? exports.Brush = Brush : null;
-})();
diff --git a/guides/assets/javascripts/syntaxhighlighter/shBrushSql.js b/guides/assets/javascripts/syntaxhighlighter/shBrushSql.js
deleted file mode 100644
index 5c2cd8806f..0000000000
--- a/guides/assets/javascripts/syntaxhighlighter/shBrushSql.js
+++ /dev/null
@@ -1,66 +0,0 @@
-/**
- * SyntaxHighlighter
- * http://alexgorbatchev.com/SyntaxHighlighter
- *
- * SyntaxHighlighter is donationware. If you are using it, please donate.
- * http://alexgorbatchev.com/SyntaxHighlighter/donate.html
- *
- * @version
- * 3.0.83 (July 02 2010)
- * 
- * @copyright
- * Copyright (C) 2004-2010 Alex Gorbatchev.
- *
- * @license
- * Dual licensed under the MIT and GPL licenses.
- */
-;(function()
-{
-	// CommonJS
-	typeof(require) != 'undefined' ? SyntaxHighlighter = require('shCore').SyntaxHighlighter : null;
-
-	function Brush()
-	{
-		var funcs	=	'abs avg case cast coalesce convert count current_timestamp ' +
-						'current_user day isnull left lower month nullif replace right ' +
-						'session_user space substring sum system_user upper user year';
-
-		var keywords =	'absolute action add after alter as asc at authorization begin bigint ' +
-						'binary bit by cascade char character check checkpoint close collate ' +
-						'column commit committed connect connection constraint contains continue ' +
-						'create cube current current_date current_time cursor database date ' +
-						'deallocate dec decimal declare default delete desc distinct double drop ' +
-						'dynamic else end end-exec escape except exec execute false fetch first ' +
-						'float for force foreign forward free from full function global goto grant ' +
-						'group grouping having hour ignore index inner insensitive insert instead ' +
-						'int integer intersect into is isolation key last level load local max min ' +
-						'minute modify move name national nchar next no numeric of off on only ' +
-						'open option order out output partial password precision prepare primary ' +
-						'prior privileges procedure public read real references relative repeatable ' +
-						'restrict return returns revoke rollback rollup rows rule schema scroll ' +
-						'second section select sequence serializable set size smallint static ' +
-						'statistics table temp temporary then time timestamp to top transaction ' +
-						'translation trigger true truncate uncommitted union unique update values ' +
-						'varchar varying view when where with work';
-
-		var operators =	'all and any between cross in join like not null or outer some';
-
-		this.regexList = [
-			{ regex: /--(.*)$/gm,												css: 'comments' },			// one line and multiline comments
-			{ regex: SyntaxHighlighter.regexLib.multiLineDoubleQuotedString,	css: 'string' },			// double quoted strings
-			{ regex: SyntaxHighlighter.regexLib.multiLineSingleQuotedString,	css: 'string' },			// single quoted strings
-			{ regex: new RegExp(this.getKeywords(funcs), 'gmi'),				css: 'color2' },			// functions
-			{ regex: new RegExp(this.getKeywords(operators), 'gmi'),			css: 'color1' },			// operators and such
-			{ regex: new RegExp(this.getKeywords(keywords), 'gmi'),				css: 'keyword' }			// keyword
-			];
-	};
-
-	Brush.prototype	= new SyntaxHighlighter.Highlighter();
-	Brush.aliases	= ['sql'];
-
-	SyntaxHighlighter.brushes.Sql = Brush;
-
-	// CommonJS
-	typeof(exports) != 'undefined' ? exports.Brush = Brush : null;
-})();
-
diff --git a/guides/assets/javascripts/syntaxhighlighter/shBrushVb.js b/guides/assets/javascripts/syntaxhighlighter/shBrushVb.js
deleted file mode 100644
index be845dc0b3..0000000000
--- a/guides/assets/javascripts/syntaxhighlighter/shBrushVb.js
+++ /dev/null
@@ -1,56 +0,0 @@
-/**
- * SyntaxHighlighter
- * http://alexgorbatchev.com/SyntaxHighlighter
- *
- * SyntaxHighlighter is donationware. If you are using it, please donate.
- * http://alexgorbatchev.com/SyntaxHighlighter/donate.html
- *
- * @version
- * 3.0.83 (July 02 2010)
- * 
- * @copyright
- * Copyright (C) 2004-2010 Alex Gorbatchev.
- *
- * @license
- * Dual licensed under the MIT and GPL licenses.
- */
-;(function()
-{
-	// CommonJS
-	typeof(require) != 'undefined' ? SyntaxHighlighter = require('shCore').SyntaxHighlighter : null;
-
-	function Brush()
-	{
-		var keywords =	'AddHandler AddressOf AndAlso Alias And Ansi As Assembly Auto ' +
-						'Boolean ByRef Byte ByVal Call Case Catch CBool CByte CChar CDate ' +
-						'CDec CDbl Char CInt Class CLng CObj Const CShort CSng CStr CType ' +
-						'Date Decimal Declare Default Delegate Dim DirectCast Do Double Each ' +
-						'Else ElseIf End Enum Erase Error Event Exit False Finally For Friend ' +
-						'Function Get GetType GoSub GoTo Handles If Implements Imports In ' +
-						'Inherits Integer Interface Is Let Lib Like Long Loop Me Mod Module ' +
-						'MustInherit MustOverride MyBase MyClass Namespace New Next Not Nothing ' +
-						'NotInheritable NotOverridable Object On Option Optional Or OrElse ' +
-						'Overloads Overridable Overrides ParamArray Preserve Private Property ' +
-						'Protected Public RaiseEvent ReadOnly ReDim REM RemoveHandler Resume ' +
-						'Return Select Set Shadows Shared Short Single Static Step Stop String ' +
-						'Structure Sub SyncLock Then Throw To True Try TypeOf Unicode Until ' +
-						'Variant When While With WithEvents WriteOnly Xor';
-
-		this.regexList = [
-			{ regex: /'.*$/gm,										css: 'comments' },			// one line comments
-			{ regex: SyntaxHighlighter.regexLib.doubleQuotedString,	css: 'string' },			// strings
-			{ regex: /^\s*#.*$/gm,									css: 'preprocessor' },		// preprocessor tags like #region and #endregion
-			{ regex: new RegExp(this.getKeywords(keywords), 'gm'),	css: 'keyword' }			// vb keyword
-			];
-
-		this.forHtmlScript(SyntaxHighlighter.regexLib.aspScriptTags);
-	};
-
-	Brush.prototype	= new SyntaxHighlighter.Highlighter();
-	Brush.aliases	= ['vb', 'vbnet'];
-
-	SyntaxHighlighter.brushes.Vb = Brush;
-
-	// CommonJS
-	typeof(exports) != 'undefined' ? exports.Brush = Brush : null;
-})();
diff --git a/guides/assets/javascripts/syntaxhighlighter/shBrushXml.js b/guides/assets/javascripts/syntaxhighlighter/shBrushXml.js
deleted file mode 100644
index 69d9fd0b1f..0000000000
--- a/guides/assets/javascripts/syntaxhighlighter/shBrushXml.js
+++ /dev/null
@@ -1,69 +0,0 @@
-/**
- * SyntaxHighlighter
- * http://alexgorbatchev.com/SyntaxHighlighter
- *
- * SyntaxHighlighter is donationware. If you are using it, please donate.
- * http://alexgorbatchev.com/SyntaxHighlighter/donate.html
- *
- * @version
- * 3.0.83 (July 02 2010)
- * 
- * @copyright
- * Copyright (C) 2004-2010 Alex Gorbatchev.
- *
- * @license
- * Dual licensed under the MIT and GPL licenses.
- */
-;(function()
-{
-	// CommonJS
-	typeof(require) != 'undefined' ? SyntaxHighlighter = require('shCore').SyntaxHighlighter : null;
-
-	function Brush()
-	{
-		function process(match, regexInfo)
-		{
-			var constructor = SyntaxHighlighter.Match,
-				code = match[0],
-				tag = new XRegExp('(&lt;|<)[\\s\\/\\?]*(?<name>[:\\w-\\.]+)', 'xg').exec(code),
-				result = []
-				;
-		
-			if (match.attributes != null) 
-			{
-				var attributes,
-					regex = new XRegExp('(?<name> [\\w:\\-\\.]+)' +
-										'\\s*=\\s*' +
-										'(?<value> ".*?"|\'.*?\'|\\w+)',
-										'xg');
-
-				while ((attributes = regex.exec(code)) != null) 
-				{
-					result.push(new constructor(attributes.name, match.index + attributes.index, 'color1'));
-					result.push(new constructor(attributes.value, match.index + attributes.index + attributes[0].indexOf(attributes.value), 'string'));
-				}
-			}
-
-			if (tag != null)
-				result.push(
-					new constructor(tag.name, match.index + tag[0].indexOf(tag.name), 'keyword')
-				);
-
-			return result;
-		}
-	
-		this.regexList = [
-			{ regex: new XRegExp('(\\&lt;|<)\\!\\[[\\w\\s]*?\\[(.|\\s)*?\\]\\](\\&gt;|>)', 'gm'),			css: 'color2' },	// <![ ... [ ... ]]>
-			{ regex: SyntaxHighlighter.regexLib.xmlComments,												css: 'comments' },	// <!-- ... -->
-			{ regex: new XRegExp('(&lt;|<)[\\s\\/\\?]*(\\w+)(?<attributes>.*?)[\\s\\/\\?]*(&gt;|>)', 'sg'), func: process }
-		];
-	};
-
-	Brush.prototype	= new SyntaxHighlighter.Highlighter();
-	Brush.aliases	= ['xml', 'xhtml', 'xslt', 'html'];
-
-	SyntaxHighlighter.brushes.Xml = Brush;
-
-	// CommonJS
-	typeof(exports) != 'undefined' ? exports.Brush = Brush : null;
-})();
diff --git a/guides/assets/javascripts/syntaxhighlighter/shCore.js b/guides/assets/javascripts/syntaxhighlighter/shCore.js
deleted file mode 100644
index b47b645472..0000000000
--- a/guides/assets/javascripts/syntaxhighlighter/shCore.js
+++ /dev/null
@@ -1,17 +0,0 @@
-/**
- * SyntaxHighlighter
- * http://alexgorbatchev.com/SyntaxHighlighter
- *
- * SyntaxHighlighter is donationware. If you are using it, please donate.
- * http://alexgorbatchev.com/SyntaxHighlighter/donate.html
- *
- * @version
- * 3.0.83 (July 02 2010)
- * 
- * @copyright
- * Copyright (C) 2004-2010 Alex Gorbatchev.
- *
- * @license
- * Dual licensed under the MIT and GPL licenses.
- */
-eval(function(p,a,c,k,e,d){e=function(c){return(c<a?'':e(parseInt(c/a)))+((c=c%a)>35?String.fromCharCode(c+29):c.toString(36))};if(!''.replace(/^/,String)){while(c--){d[e(c)]=k[c]||e(c)}k=[function(e){return d[e]}];e=function(){return'\\w+'};c=1};while(c--){if(k[c]){p=p.replace(new RegExp('\\b'+e(c)+'\\b','g'),k[c])}}return p}('K M;I(M)1S 2U("2a\'t 4k M 4K 2g 3l 4G 4H");(6(){6 r(f,e){I(!M.1R(f))1S 3m("3s 15 4R");K a=f.1w;f=M(f.1m,t(f)+(e||""));I(a)f.1w={1m:a.1m,19:a.19?a.19.1a(0):N};H f}6 t(f){H(f.1J?"g":"")+(f.4s?"i":"")+(f.4p?"m":"")+(f.4v?"x":"")+(f.3n?"y":"")}6 B(f,e,a,b){K c=u.L,d,h,g;v=R;5K{O(;c--;){g=u[c];I(a&g.3r&&(!g.2p||g.2p.W(b))){g.2q.12=e;I((h=g.2q.X(f))&&h.P===e){d={3k:g.2b.W(b,h,a),1C:h};1N}}}}5v(i){1S i}5q{v=11}H d}6 p(f,e,a){I(3b.Z.1i)H f.1i(e,a);O(a=a||0;a<f.L;a++)I(f[a]===e)H a;H-1}M=6(f,e){K a=[],b=M.1B,c=0,d,h;I(M.1R(f)){I(e!==1d)1S 3m("2a\'t 5r 5I 5F 5B 5C 15 5E 5p");H r(f)}I(v)1S 2U("2a\'t W 3l M 59 5m 5g 5x 5i");e=e||"";O(d={2N:11,19:[],2K:6(g){H e.1i(g)>-1},3d:6(g){e+=g}};c<f.L;)I(h=B(f,c,b,d)){a.U(h.3k);c+=h.1C[0].L||1}Y I(h=n.X.W(z[b],f.1a(c))){a.U(h[0]);c+=h[0].L}Y{h=f.3a(c);I(h==="[")b=M.2I;Y I(h==="]")b=M.1B;a.U(h);c++}a=15(a.1K(""),n.Q.W(e,w,""));a.1w={1m:f,19:d.2N?d.19:N};H a};M.3v="1.5.0";M.2I=1;M.1B=2;K C=/\\$(?:(\\d\\d?|[$&`\'])|{([$\\w]+)})/g,w=/[^5h]+|([\\s\\S])(?=[\\s\\S]*\\1)/g,A=/^(?:[?*+]|{\\d+(?:,\\d*)?})\\??/,v=11,u=[],n={X:15.Z.X,1A:15.Z.1A,1C:1r.Z.1C,Q:1r.Z.Q,1e:1r.Z.1e},x=n.X.W(/()??/,"")[1]===1d,D=6(){K f=/^/g;n.1A.W(f,"");H!f.12}(),y=6(){K f=/x/g;n.Q.W("x",f,"");H!f.12}(),E=15.Z.3n!==1d,z={};z[M.2I]=/^(?:\\\\(?:[0-3][0-7]{0,2}|[4-7][0-7]?|x[\\29-26-f]{2}|u[\\29-26-f]{4}|c[A-3o-z]|[\\s\\S]))/;z[M.1B]=/^(?:\\\\(?:0(?:[0-3][0-7]{0,2}|[4-7][0-7]?)?|[1-9]\\d*|x[\\29-26-f]{2}|u[\\29-26-f]{4}|c[A-3o-z]|[\\s\\S])|\\(\\?[:=!]|[?*+]\\?|{\\d+(?:,\\d*)?}\\??)/;M.1h=6(f,e,a,b){u.U({2q:r(f,"g"+(E?"y":"")),2b:e,3r:a||M.1B,2p:b||N})};M.2n=6(f,e){K a=f+"/"+(e||"");H M.2n[a]||(M.2n[a]=M(f,e))};M.3c=6(f){H 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diff --git a/guides/assets/stylesheets/main.css b/guides/assets/stylesheets/main.css
index ed558e4793..b27776745a 100644
--- a/guides/assets/stylesheets/main.css
+++ b/guides/assets/stylesheets/main.css
@@ -16,7 +16,6 @@
 .large {font-size: larger;}
 .hide {display: none;}
 
-li ul, li ol { margin:0 1.5em; }
 ul, ol { margin: 0 1.5em 1.5em 1.5em; }
 
 ul { list-style-type: disc; }
@@ -295,6 +294,10 @@ a, a:link, a:visited {
 #mainCol a, #subCol a, #feature a {color: #980905;}
 #mainCol a code, #subCol a code, #feature a code {color: #980905;}
 
+#mainCol a.anchorlink, #mainCol a.anchorlink code {color: #333;}
+#mainCol a.anchorlink { text-decoration: none; }
+#mainCol a.anchorlink:hover { text-decoration: underline; }
+
 /* Navigation
 --------------------------------------- */
 
@@ -602,6 +605,8 @@ h6 {
   font-weight: normal;
 }
 
+#subCol li ul, li ol { margin:0 1.5em; }
+
 div.code_container {
   background: #EEE url(../images/tab_grey.gif) no-repeat left top;
   padding: 0.25em 1em 0.5em 48px;
diff --git a/guides/assets/stylesheets/responsive-tables.css b/guides/assets/stylesheets/responsive-tables.css
index f5fbcbf948..f5fbcbf948 100755..100644
--- a/guides/assets/stylesheets/responsive-tables.css
+++ b/guides/assets/stylesheets/responsive-tables.css
diff --git a/guides/assets/stylesheets/syntaxhighlighter/shCore.css b/guides/assets/stylesheets/syntaxhighlighter/shCore.css
index 34f6864a15..7e1e199343 100644
--- a/guides/assets/stylesheets/syntaxhighlighter/shCore.css
+++ b/guides/assets/stylesheets/syntaxhighlighter/shCore.css
@@ -33,7 +33,7 @@
   height: auto !important;
   left: auto !important;
   line-height: 1.1em !important;
-  margin: 0 !important;
+  margin: 0 0 0.5px 0 !important;
   outline: 0 !important;
   overflow: visible !important;
   padding: 0 !important;
diff --git a/guides/assets/stylesheets/syntaxhighlighter/shCoreDefault.css b/guides/assets/stylesheets/syntaxhighlighter/shCoreDefault.css
deleted file mode 100644
index 08f9e10e4e..0000000000
--- a/guides/assets/stylesheets/syntaxhighlighter/shCoreDefault.css
+++ /dev/null
@@ -1,328 +0,0 @@
-/**
- * SyntaxHighlighter
- * http://alexgorbatchev.com/SyntaxHighlighter
- *
- * SyntaxHighlighter is donationware. If you are using it, please donate.
- * http://alexgorbatchev.com/SyntaxHighlighter/donate.html
- *
- * @version
- * 3.0.83 (July 02 2010)
- * 
- * @copyright
- * Copyright (C) 2004-2010 Alex Gorbatchev.
- *
- * @license
- * Dual licensed under the MIT and GPL licenses.
- */
-.syntaxhighlighter a,
-.syntaxhighlighter div,
-.syntaxhighlighter code,
-.syntaxhighlighter table,
-.syntaxhighlighter table td,
-.syntaxhighlighter table tr,
-.syntaxhighlighter table tbody,
-.syntaxhighlighter table thead,
-.syntaxhighlighter table caption,
-.syntaxhighlighter textarea {
-  -moz-border-radius: 0 0 0 0 !important;
-  -webkit-border-radius: 0 0 0 0 !important;
-  background: none !important;
-  border: 0 !important;
-  bottom: auto !important;
-  float: none !important;
-  height: auto !important;
-  left: auto !important;
-  line-height: 1.1em !important;
-  margin: 0 !important;
-  outline: 0 !important;
-  overflow: visible !important;
-  padding: 0 !important;
-  position: static !important;
-  right: auto !important;
-  text-align: left !important;
-  top: auto !important;
-  vertical-align: baseline !important;
-  width: auto !important;
-  box-sizing: content-box !important;
-  font-family: "Consolas", "Bitstream Vera Sans Mono", "Courier New", Courier, monospace !important;
-  font-weight: normal !important;
-  font-style: normal !important;
-  font-size: 1em !important;
-  min-height: inherit !important;
-  min-height: auto !important;
-}
-
-.syntaxhighlighter {
-  width: 100% !important;
-  margin: 1em 0 1em 0 !important;
-  position: relative !important;
-  overflow: auto !important;
-  font-size: 1em !important;
-}
-.syntaxhighlighter.source {
-  overflow: hidden !important;
-}
-.syntaxhighlighter .bold {
-  font-weight: bold !important;
-}
-.syntaxhighlighter .italic {
-  font-style: italic !important;
-}
-.syntaxhighlighter .line {
-  white-space: pre !important;
-}
-.syntaxhighlighter table {
-  width: 100% !important;
-}
-.syntaxhighlighter table caption {
-  text-align: left !important;
-  padding: .5em 0 0.5em 1em !important;
-}
-.syntaxhighlighter table td.code {
-  width: 100% !important;
-}
-.syntaxhighlighter table td.code .container {
-  position: relative !important;
-}
-.syntaxhighlighter table td.code .container textarea {
-  box-sizing: border-box !important;
-  position: absolute !important;
-  left: 0 !important;
-  top: 0 !important;
-  width: 100% !important;
-  height: 100% !important;
-  border: none !important;
-  background: white !important;
-  padding-left: 1em !important;
-  overflow: hidden !important;
-  white-space: pre !important;
-}
-.syntaxhighlighter table td.gutter .line {
-  text-align: right !important;
-  padding: 0 0.5em 0 1em !important;
-}
-.syntaxhighlighter table td.code .line {
-  padding: 0 1em !important;
-}
-.syntaxhighlighter.nogutter td.code .container textarea, .syntaxhighlighter.nogutter td.code .line {
-  padding-left: 0em !important;
-}
-.syntaxhighlighter.show {
-  display: block !important;
-}
-.syntaxhighlighter.collapsed table {
-  display: none !important;
-}
-.syntaxhighlighter.collapsed .toolbar {
-  padding: 0.1em 0.8em 0em 0.8em !important;
-  font-size: 1em !important;
-  position: static !important;
-  width: auto !important;
-  height: auto !important;
-}
-.syntaxhighlighter.collapsed .toolbar span {
-  display: inline !important;
-  margin-right: 1em !important;
-}
-.syntaxhighlighter.collapsed .toolbar span a {
-  padding: 0 !important;
-  display: none !important;
-}
-.syntaxhighlighter.collapsed .toolbar span a.expandSource {
-  display: inline !important;
-}
-.syntaxhighlighter .toolbar {
-  position: absolute !important;
-  right: 1px !important;
-  top: 1px !important;
-  width: 11px !important;
-  height: 11px !important;
-  font-size: 10px !important;
-  z-index: 10 !important;
-}
-.syntaxhighlighter .toolbar span.title {
-  display: inline !important;
-}
-.syntaxhighlighter .toolbar a {
-  display: block !important;
-  text-align: center !important;
-  text-decoration: none !important;
-  padding-top: 1px !important;
-}
-.syntaxhighlighter .toolbar a.expandSource {
-  display: none !important;
-}
-.syntaxhighlighter.ie {
-  font-size: .9em !important;
-  padding: 1px 0 1px 0 !important;
-}
-.syntaxhighlighter.ie .toolbar {
-  line-height: 8px !important;
-}
-.syntaxhighlighter.ie .toolbar a {
-  padding-top: 0px !important;
-}
-.syntaxhighlighter.printing .line.alt1 .content,
-.syntaxhighlighter.printing .line.alt2 .content,
-.syntaxhighlighter.printing .line.highlighted .number,
-.syntaxhighlighter.printing .line.highlighted.alt1 .content,
-.syntaxhighlighter.printing .line.highlighted.alt2 .content {
-  background: none !important;
-}
-.syntaxhighlighter.printing .line .number {
-  color: #bbbbbb !important;
-}
-.syntaxhighlighter.printing .line .content {
-  color: black !important;
-}
-.syntaxhighlighter.printing .toolbar {
-  display: none !important;
-}
-.syntaxhighlighter.printing a {
-  text-decoration: none !important;
-}
-.syntaxhighlighter.printing .plain, .syntaxhighlighter.printing .plain a {
-  color: black !important;
-}
-.syntaxhighlighter.printing .comments, .syntaxhighlighter.printing .comments a {
-  color: #008200 !important;
-}
-.syntaxhighlighter.printing .string, .syntaxhighlighter.printing .string a {
-  color: blue !important;
-}
-.syntaxhighlighter.printing .keyword {
-  color: #006699 !important;
-  font-weight: bold !important;
-}
-.syntaxhighlighter.printing .preprocessor {
-  color: gray !important;
-}
-.syntaxhighlighter.printing .variable {
-  color: #aa7700 !important;
-}
-.syntaxhighlighter.printing .value {
-  color: #009900 !important;
-}
-.syntaxhighlighter.printing .functions {
-  color: #ff1493 !important;
-}
-.syntaxhighlighter.printing .constants {
-  color: #0066cc !important;
-}
-.syntaxhighlighter.printing .script {
-  font-weight: bold !important;
-}
-.syntaxhighlighter.printing .color1, .syntaxhighlighter.printing .color1 a {
-  color: gray !important;
-}
-.syntaxhighlighter.printing .color2, .syntaxhighlighter.printing .color2 a {
-  color: #ff1493 !important;
-}
-.syntaxhighlighter.printing .color3, .syntaxhighlighter.printing .color3 a {
-  color: red !important;
-}
-.syntaxhighlighter.printing .break, .syntaxhighlighter.printing .break a {
-  color: black !important;
-}
-
-.syntaxhighlighter {
-  background-color: white !important;
-}
-.syntaxhighlighter .line.alt1 {
-  background-color: white !important;
-}
-.syntaxhighlighter .line.alt2 {
-  background-color: white !important;
-}
-.syntaxhighlighter .line.highlighted.alt1, .syntaxhighlighter .line.highlighted.alt2 {
-  background-color: #e0e0e0 !important;
-}
-.syntaxhighlighter .line.highlighted.number {
-  color: black !important;
-}
-.syntaxhighlighter table caption {
-  color: black !important;
-}
-.syntaxhighlighter .gutter {
-  color: #afafaf !important;
-}
-.syntaxhighlighter .gutter .line {
-  border-right: 3px solid #6ce26c !important;
-}
-.syntaxhighlighter .gutter .line.highlighted {
-  background-color: #6ce26c !important;
-  color: white !important;
-}
-.syntaxhighlighter.printing .line .content {
-  border: none !important;
-}
-.syntaxhighlighter.collapsed {
-  overflow: visible !important;
-}
-.syntaxhighlighter.collapsed .toolbar {
-  color: blue !important;
-  background: white !important;
-  border: 1px solid #6ce26c !important;
-}
-.syntaxhighlighter.collapsed .toolbar a {
-  color: blue !important;
-}
-.syntaxhighlighter.collapsed .toolbar a:hover {
-  color: red !important;
-}
-.syntaxhighlighter .toolbar {
-  color: white !important;
-  background: #6ce26c !important;
-  border: none !important;
-}
-.syntaxhighlighter .toolbar a {
-  color: white !important;
-}
-.syntaxhighlighter .toolbar a:hover {
-  color: black !important;
-}
-.syntaxhighlighter .plain, .syntaxhighlighter .plain a {
-  color: black !important;
-}
-.syntaxhighlighter .comments, .syntaxhighlighter .comments a {
-  color: #008200 !important;
-}
-.syntaxhighlighter .string, .syntaxhighlighter .string a {
-  color: blue !important;
-}
-.syntaxhighlighter .keyword {
-  color: #006699 !important;
-}
-.syntaxhighlighter .preprocessor {
-  color: gray !important;
-}
-.syntaxhighlighter .variable {
-  color: #aa7700 !important;
-}
-.syntaxhighlighter .value {
-  color: #009900 !important;
-}
-.syntaxhighlighter .functions {
-  color: #ff1493 !important;
-}
-.syntaxhighlighter .constants {
-  color: #0066cc !important;
-}
-.syntaxhighlighter .script {
-  font-weight: bold !important;
-  color: #006699 !important;
-  background-color: none !important;
-}
-.syntaxhighlighter .color1, .syntaxhighlighter .color1 a {
-  color: gray !important;
-}
-.syntaxhighlighter .color2, .syntaxhighlighter .color2 a {
-  color: #ff1493 !important;
-}
-.syntaxhighlighter .color3, .syntaxhighlighter .color3 a {
-  color: red !important;
-}
-
-.syntaxhighlighter .keyword {
-  font-weight: bold !important;
-}
diff --git a/guides/assets/stylesheets/syntaxhighlighter/shCoreDjango.css b/guides/assets/stylesheets/syntaxhighlighter/shCoreDjango.css
deleted file mode 100644
index 1db1f70cb0..0000000000
--- a/guides/assets/stylesheets/syntaxhighlighter/shCoreDjango.css
+++ /dev/null
@@ -1,331 +0,0 @@
-/**
- * SyntaxHighlighter
- * http://alexgorbatchev.com/SyntaxHighlighter
- *
- * SyntaxHighlighter is donationware. If you are using it, please donate.
- * http://alexgorbatchev.com/SyntaxHighlighter/donate.html
- *
- * @version
- * 3.0.83 (July 02 2010)
- * 
- * @copyright
- * Copyright (C) 2004-2010 Alex Gorbatchev.
- *
- * @license
- * Dual licensed under the MIT and GPL licenses.
- */
-.syntaxhighlighter a,
-.syntaxhighlighter div,
-.syntaxhighlighter code,
-.syntaxhighlighter table,
-.syntaxhighlighter table td,
-.syntaxhighlighter table tr,
-.syntaxhighlighter table tbody,
-.syntaxhighlighter table thead,
-.syntaxhighlighter table caption,
-.syntaxhighlighter textarea {
-  -moz-border-radius: 0 0 0 0 !important;
-  -webkit-border-radius: 0 0 0 0 !important;
-  background: none !important;
-  border: 0 !important;
-  bottom: auto !important;
-  float: none !important;
-  height: auto !important;
-  left: auto !important;
-  line-height: 1.1em !important;
-  margin: 0 !important;
-  outline: 0 !important;
-  overflow: visible !important;
-  padding: 0 !important;
-  position: static !important;
-  right: auto !important;
-  text-align: left !important;
-  top: auto !important;
-  vertical-align: baseline !important;
-  width: auto !important;
-  box-sizing: content-box !important;
-  font-family: "Consolas", "Bitstream Vera Sans Mono", "Courier New", Courier, monospace !important;
-  font-weight: normal !important;
-  font-style: normal !important;
-  font-size: 1em !important;
-  min-height: inherit !important;
-  min-height: auto !important;
-}
-
-.syntaxhighlighter {
-  width: 100% !important;
-  margin: 1em 0 1em 0 !important;
-  position: relative !important;
-  overflow: auto !important;
-  font-size: 1em !important;
-}
-.syntaxhighlighter.source {
-  overflow: hidden !important;
-}
-.syntaxhighlighter .bold {
-  font-weight: bold !important;
-}
-.syntaxhighlighter .italic {
-  font-style: italic !important;
-}
-.syntaxhighlighter .line {
-  white-space: pre !important;
-}
-.syntaxhighlighter table {
-  width: 100% !important;
-}
-.syntaxhighlighter table caption {
-  text-align: left !important;
-  padding: .5em 0 0.5em 1em !important;
-}
-.syntaxhighlighter table td.code {
-  width: 100% !important;
-}
-.syntaxhighlighter table td.code .container {
-  position: relative !important;
-}
-.syntaxhighlighter table td.code .container textarea {
-  box-sizing: border-box !important;
-  position: absolute !important;
-  left: 0 !important;
-  top: 0 !important;
-  width: 100% !important;
-  height: 100% !important;
-  border: none !important;
-  background: white !important;
-  padding-left: 1em !important;
-  overflow: hidden !important;
-  white-space: pre !important;
-}
-.syntaxhighlighter table td.gutter .line {
-  text-align: right !important;
-  padding: 0 0.5em 0 1em !important;
-}
-.syntaxhighlighter table td.code .line {
-  padding: 0 1em !important;
-}
-.syntaxhighlighter.nogutter td.code .container textarea, .syntaxhighlighter.nogutter td.code .line {
-  padding-left: 0em !important;
-}
-.syntaxhighlighter.show {
-  display: block !important;
-}
-.syntaxhighlighter.collapsed table {
-  display: none !important;
-}
-.syntaxhighlighter.collapsed .toolbar {
-  padding: 0.1em 0.8em 0em 0.8em !important;
-  font-size: 1em !important;
-  position: static !important;
-  width: auto !important;
-  height: auto !important;
-}
-.syntaxhighlighter.collapsed .toolbar span {
-  display: inline !important;
-  margin-right: 1em !important;
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-.syntaxhighlighter.printing .value {
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-.syntaxhighlighter.printing .functions {
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-.syntaxhighlighter.printing .constants {
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-.syntaxhighlighter.printing .script {
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-.syntaxhighlighter.printing .color1, .syntaxhighlighter.printing .color1 a {
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-  color: red !important;
-}
-.syntaxhighlighter.printing .break, .syntaxhighlighter.printing .break a {
-  color: black !important;
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-
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-.syntaxhighlighter .line.alt2 {
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-.syntaxhighlighter .line.highlighted.number {
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-}
-.syntaxhighlighter table caption {
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-.syntaxhighlighter .gutter .line {
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-.syntaxhighlighter .gutter .line.highlighted {
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-  color: #0a2b1d !important;
-}
-.syntaxhighlighter.printing .line .content {
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-  background: black !important;
-  border: 1px solid #41a83e !important;
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-.syntaxhighlighter .toolbar a:hover {
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-}
-.syntaxhighlighter .plain, .syntaxhighlighter .plain a {
-  color: #f8f8f8 !important;
-}
-.syntaxhighlighter .comments, .syntaxhighlighter .comments a {
-  color: #336442 !important;
-}
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-  color: #9df39f !important;
-}
-.syntaxhighlighter .keyword {
-  color: #96dd3b !important;
-}
-.syntaxhighlighter .preprocessor {
-  color: #91bb9e !important;
-}
-.syntaxhighlighter .variable {
-  color: #ffaa3e !important;
-}
-.syntaxhighlighter .value {
-  color: #f7e741 !important;
-}
-.syntaxhighlighter .functions {
-  color: #ffaa3e !important;
-}
-.syntaxhighlighter .constants {
-  color: #e0e8ff !important;
-}
-.syntaxhighlighter .script {
-  font-weight: bold !important;
-  color: #96dd3b !important;
-  background-color: none !important;
-}
-.syntaxhighlighter .color1, .syntaxhighlighter .color1 a {
-  color: #eb939a !important;
-}
-.syntaxhighlighter .color2, .syntaxhighlighter .color2 a {
-  color: #91bb9e !important;
-}
-.syntaxhighlighter .color3, .syntaxhighlighter .color3 a {
-  color: #edef7d !important;
-}
-
-.syntaxhighlighter .comments {
-  font-style: italic !important;
-}
-.syntaxhighlighter .keyword {
-  font-weight: bold !important;
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diff --git a/guides/assets/stylesheets/syntaxhighlighter/shCoreEclipse.css b/guides/assets/stylesheets/syntaxhighlighter/shCoreEclipse.css
deleted file mode 100644
index a45de9fd8e..0000000000
--- a/guides/assets/stylesheets/syntaxhighlighter/shCoreEclipse.css
+++ /dev/null
@@ -1,339 +0,0 @@
-/**
- * SyntaxHighlighter
- * http://alexgorbatchev.com/SyntaxHighlighter
- *
- * SyntaxHighlighter is donationware. If you are using it, please donate.
- * http://alexgorbatchev.com/SyntaxHighlighter/donate.html
- *
- * @version
- * 3.0.83 (July 02 2010)
- * 
- * @copyright
- * Copyright (C) 2004-2010 Alex Gorbatchev.
- *
- * @license
- * Dual licensed under the MIT and GPL licenses.
- */
-.syntaxhighlighter a,
-.syntaxhighlighter div,
-.syntaxhighlighter code,
-.syntaxhighlighter table,
-.syntaxhighlighter table td,
-.syntaxhighlighter table tr,
-.syntaxhighlighter table tbody,
-.syntaxhighlighter table thead,
-.syntaxhighlighter table caption,
-.syntaxhighlighter textarea {
-  -moz-border-radius: 0 0 0 0 !important;
-  -webkit-border-radius: 0 0 0 0 !important;
-  background: none !important;
-  border: 0 !important;
-  bottom: auto !important;
-  float: none !important;
-  height: auto !important;
-  left: auto !important;
-  line-height: 1.1em !important;
-  margin: 0 !important;
-  outline: 0 !important;
-  overflow: visible !important;
-  padding: 0 !important;
-  position: static !important;
-  right: auto !important;
-  text-align: left !important;
-  top: auto !important;
-  vertical-align: baseline !important;
-  width: auto !important;
-  box-sizing: content-box !important;
-  font-family: "Consolas", "Bitstream Vera Sans Mono", "Courier New", Courier, monospace !important;
-  font-weight: normal !important;
-  font-style: normal !important;
-  font-size: 1em !important;
-  min-height: inherit !important;
-  min-height: auto !important;
-}
-
-.syntaxhighlighter {
-  width: 100% !important;
-  margin: 1em 0 1em 0 !important;
-  position: relative !important;
-  overflow: auto !important;
-  font-size: 1em !important;
-}
-.syntaxhighlighter.source {
-  overflow: hidden !important;
-}
-.syntaxhighlighter .bold {
-  font-weight: bold !important;
-}
-.syntaxhighlighter .italic {
-  font-style: italic !important;
-}
-.syntaxhighlighter .line {
-  white-space: pre !important;
-}
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-}
-.syntaxhighlighter table caption {
-  text-align: left !important;
-  padding: .5em 0 0.5em 1em !important;
-}
-.syntaxhighlighter table td.code {
-  width: 100% !important;
-}
-.syntaxhighlighter table td.code .container {
-  position: relative !important;
-}
-.syntaxhighlighter table td.code .container textarea {
-  box-sizing: border-box !important;
-  position: absolute !important;
-  left: 0 !important;
-  top: 0 !important;
-  width: 100% !important;
-  height: 100% !important;
-  border: none !important;
-  background: white !important;
-  padding-left: 1em !important;
-  overflow: hidden !important;
-  white-space: pre !important;
-}
-.syntaxhighlighter table td.gutter .line {
-  text-align: right !important;
-  padding: 0 0.5em 0 1em !important;
-}
-.syntaxhighlighter table td.code .line {
-  padding: 0 1em !important;
-}
-.syntaxhighlighter.nogutter td.code .container textarea, .syntaxhighlighter.nogutter td.code .line {
-  padding-left: 0em !important;
-}
-.syntaxhighlighter.show {
-  display: block !important;
-}
-.syntaxhighlighter.collapsed table {
-  display: none !important;
-}
-.syntaxhighlighter.collapsed .toolbar {
-  padding: 0.1em 0.8em 0em 0.8em !important;
-  font-size: 1em !important;
-  position: static !important;
-  width: auto !important;
-  height: auto !important;
-}
-.syntaxhighlighter.collapsed .toolbar span {
-  display: inline !important;
-  margin-right: 1em !important;
-}
-.syntaxhighlighter.collapsed .toolbar span a {
-  padding: 0 !important;
-  display: none !important;
-}
-.syntaxhighlighter.collapsed .toolbar span a.expandSource {
-  display: inline !important;
-}
-.syntaxhighlighter .toolbar {
-  position: absolute !important;
-  right: 1px !important;
-  top: 1px !important;
-  width: 11px !important;
-  height: 11px !important;
-  font-size: 10px !important;
-  z-index: 10 !important;
-}
-.syntaxhighlighter .toolbar span.title {
-  display: inline !important;
-}
-.syntaxhighlighter .toolbar a {
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-  text-decoration: none !important;
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-.syntaxhighlighter.ie {
-  font-size: .9em !important;
-  padding: 1px 0 1px 0 !important;
-}
-.syntaxhighlighter.ie .toolbar {
-  line-height: 8px !important;
-}
-.syntaxhighlighter.ie .toolbar a {
-  padding-top: 0px !important;
-}
-.syntaxhighlighter.printing .line.alt1 .content,
-.syntaxhighlighter.printing .line.alt2 .content,
-.syntaxhighlighter.printing .line.highlighted .number,
-.syntaxhighlighter.printing .line.highlighted.alt1 .content,
-.syntaxhighlighter.printing .line.highlighted.alt2 .content {
-  background: none !important;
-}
-.syntaxhighlighter.printing .line .number {
-  color: #bbbbbb !important;
-}
-.syntaxhighlighter.printing .line .content {
-  color: black !important;
-}
-.syntaxhighlighter.printing .toolbar {
-  display: none !important;
-}
-.syntaxhighlighter.printing a {
-  text-decoration: none !important;
-}
-.syntaxhighlighter.printing .plain, .syntaxhighlighter.printing .plain a {
-  color: black !important;
-}
-.syntaxhighlighter.printing .comments, .syntaxhighlighter.printing .comments a {
-  color: #008200 !important;
-}
-.syntaxhighlighter.printing .string, .syntaxhighlighter.printing .string a {
-  color: blue !important;
-}
-.syntaxhighlighter.printing .keyword {
-  color: #006699 !important;
-  font-weight: bold !important;
-}
-.syntaxhighlighter.printing .preprocessor {
-  color: gray !important;
-}
-.syntaxhighlighter.printing .variable {
-  color: #aa7700 !important;
-}
-.syntaxhighlighter.printing .value {
-  color: #009900 !important;
-}
-.syntaxhighlighter.printing .functions {
-  color: #ff1493 !important;
-}
-.syntaxhighlighter.printing .constants {
-  color: #0066cc !important;
-}
-.syntaxhighlighter.printing .script {
-  font-weight: bold !important;
-}
-.syntaxhighlighter.printing .color1, .syntaxhighlighter.printing .color1 a {
-  color: gray !important;
-}
-.syntaxhighlighter.printing .color2, .syntaxhighlighter.printing .color2 a {
-  color: #ff1493 !important;
-}
-.syntaxhighlighter.printing .color3, .syntaxhighlighter.printing .color3 a {
-  color: red !important;
-}
-.syntaxhighlighter.printing .break, .syntaxhighlighter.printing .break a {
-  color: black !important;
-}
-
-.syntaxhighlighter {
-  background-color: white !important;
-}
-.syntaxhighlighter .line.alt1 {
-  background-color: white !important;
-}
-.syntaxhighlighter .line.alt2 {
-  background-color: white !important;
-}
-.syntaxhighlighter .line.highlighted.alt1, .syntaxhighlighter .line.highlighted.alt2 {
-  background-color: #c3defe !important;
-}
-.syntaxhighlighter .line.highlighted.number {
-  color: white !important;
-}
-.syntaxhighlighter table caption {
-  color: black !important;
-}
-.syntaxhighlighter .gutter {
-  color: #787878 !important;
-}
-.syntaxhighlighter .gutter .line {
-  border-right: 3px solid #d4d0c8 !important;
-}
-.syntaxhighlighter .gutter .line.highlighted {
-  background-color: #d4d0c8 !important;
-  color: white !important;
-}
-.syntaxhighlighter.printing .line .content {
-  border: none !important;
-}
-.syntaxhighlighter.collapsed {
-  overflow: visible !important;
-}
-.syntaxhighlighter.collapsed .toolbar {
-  color: #3f5fbf !important;
-  background: white !important;
-  border: 1px solid #d4d0c8 !important;
-}
-.syntaxhighlighter.collapsed .toolbar a {
-  color: #3f5fbf !important;
-}
-.syntaxhighlighter.collapsed .toolbar a:hover {
-  color: #aa7700 !important;
-}
-.syntaxhighlighter .toolbar {
-  color: #a0a0a0 !important;
-  background: #d4d0c8 !important;
-  border: none !important;
-}
-.syntaxhighlighter .toolbar a {
-  color: #a0a0a0 !important;
-}
-.syntaxhighlighter .toolbar a:hover {
-  color: red !important;
-}
-.syntaxhighlighter .plain, .syntaxhighlighter .plain a {
-  color: black !important;
-}
-.syntaxhighlighter .comments, .syntaxhighlighter .comments a {
-  color: #3f5fbf !important;
-}
-.syntaxhighlighter .string, .syntaxhighlighter .string a {
-  color: #2a00ff !important;
-}
-.syntaxhighlighter .keyword {
-  color: #7f0055 !important;
-}
-.syntaxhighlighter .preprocessor {
-  color: #646464 !important;
-}
-.syntaxhighlighter .variable {
-  color: #aa7700 !important;
-}
-.syntaxhighlighter .value {
-  color: #009900 !important;
-}
-.syntaxhighlighter .functions {
-  color: #ff1493 !important;
-}
-.syntaxhighlighter .constants {
-  color: #0066cc !important;
-}
-.syntaxhighlighter .script {
-  font-weight: bold !important;
-  color: #7f0055 !important;
-  background-color: none !important;
-}
-.syntaxhighlighter .color1, .syntaxhighlighter .color1 a {
-  color: gray !important;
-}
-.syntaxhighlighter .color2, .syntaxhighlighter .color2 a {
-  color: #ff1493 !important;
-}
-.syntaxhighlighter .color3, .syntaxhighlighter .color3 a {
-  color: red !important;
-}
-
-.syntaxhighlighter .keyword {
-  font-weight: bold !important;
-}
-.syntaxhighlighter .xml .keyword {
-  color: #3f7f7f !important;
-  font-weight: normal !important;
-}
-.syntaxhighlighter .xml .color1, .syntaxhighlighter .xml .color1 a {
-  color: #7f007f !important;
-}
-.syntaxhighlighter .xml .string {
-  font-style: italic !important;
-  color: #2a00ff !important;
-}
diff --git a/guides/assets/stylesheets/syntaxhighlighter/shCoreEmacs.css b/guides/assets/stylesheets/syntaxhighlighter/shCoreEmacs.css
deleted file mode 100644
index 706c77a0a8..0000000000
--- a/guides/assets/stylesheets/syntaxhighlighter/shCoreEmacs.css
+++ /dev/null
@@ -1,324 +0,0 @@
-/**
- * SyntaxHighlighter
- * http://alexgorbatchev.com/SyntaxHighlighter
- *
- * SyntaxHighlighter is donationware. If you are using it, please donate.
- * http://alexgorbatchev.com/SyntaxHighlighter/donate.html
- *
- * @version
- * 3.0.83 (July 02 2010)
- * 
- * @copyright
- * Copyright (C) 2004-2010 Alex Gorbatchev.
- *
- * @license
- * Dual licensed under the MIT and GPL licenses.
- */
-.syntaxhighlighter a,
-.syntaxhighlighter div,
-.syntaxhighlighter code,
-.syntaxhighlighter table,
-.syntaxhighlighter table td,
-.syntaxhighlighter table tr,
-.syntaxhighlighter table tbody,
-.syntaxhighlighter table thead,
-.syntaxhighlighter table caption,
-.syntaxhighlighter textarea {
-  -moz-border-radius: 0 0 0 0 !important;
-  -webkit-border-radius: 0 0 0 0 !important;
-  background: none !important;
-  border: 0 !important;
-  bottom: auto !important;
-  float: none !important;
-  height: auto !important;
-  left: auto !important;
-  line-height: 1.1em !important;
-  margin: 0 !important;
-  outline: 0 !important;
-  overflow: visible !important;
-  padding: 0 !important;
-  position: static !important;
-  right: auto !important;
-  text-align: left !important;
-  top: auto !important;
-  vertical-align: baseline !important;
-  width: auto !important;
-  box-sizing: content-box !important;
-  font-family: "Consolas", "Bitstream Vera Sans Mono", "Courier New", Courier, monospace !important;
-  font-weight: normal !important;
-  font-style: normal !important;
-  font-size: 1em !important;
-  min-height: inherit !important;
-  min-height: auto !important;
-}
-
-.syntaxhighlighter {
-  width: 100% !important;
-  margin: 1em 0 1em 0 !important;
-  position: relative !important;
-  overflow: auto !important;
-  font-size: 1em !important;
-}
-.syntaxhighlighter.source {
-  overflow: hidden !important;
-}
-.syntaxhighlighter .bold {
-  font-weight: bold !important;
-}
-.syntaxhighlighter .italic {
-  font-style: italic !important;
-}
-.syntaxhighlighter .line {
-  white-space: pre !important;
-}
-.syntaxhighlighter table {
-  width: 100% !important;
-}
-.syntaxhighlighter table caption {
-  text-align: left !important;
-  padding: .5em 0 0.5em 1em !important;
-}
-.syntaxhighlighter table td.code {
-  width: 100% !important;
-}
-.syntaxhighlighter table td.code .container {
-  position: relative !important;
-}
-.syntaxhighlighter table td.code .container textarea {
-  box-sizing: border-box !important;
-  position: absolute !important;
-  left: 0 !important;
-  top: 0 !important;
-  width: 100% !important;
-  height: 100% !important;
-  border: none !important;
-  background: white !important;
-  padding-left: 1em !important;
-  overflow: hidden !important;
-  white-space: pre !important;
-}
-.syntaxhighlighter table td.gutter .line {
-  text-align: right !important;
-  padding: 0 0.5em 0 1em !important;
-}
-.syntaxhighlighter table td.code .line {
-  padding: 0 1em !important;
-}
-.syntaxhighlighter.nogutter td.code .container textarea, .syntaxhighlighter.nogutter td.code .line {
-  padding-left: 0em !important;
-}
-.syntaxhighlighter.show {
-  display: block !important;
-}
-.syntaxhighlighter.collapsed table {
-  display: none !important;
-}
-.syntaxhighlighter.collapsed .toolbar {
-  padding: 0.1em 0.8em 0em 0.8em !important;
-  font-size: 1em !important;
-  position: static !important;
-  width: auto !important;
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-}
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-  display: inline !important;
-  margin-right: 1em !important;
-}
-.syntaxhighlighter.collapsed .toolbar span a {
-  padding: 0 !important;
-  display: none !important;
-}
-.syntaxhighlighter.collapsed .toolbar span a.expandSource {
-  display: inline !important;
-}
-.syntaxhighlighter .toolbar {
-  position: absolute !important;
-  right: 1px !important;
-  top: 1px !important;
-  width: 11px !important;
-  height: 11px !important;
-  font-size: 10px !important;
-  z-index: 10 !important;
-}
-.syntaxhighlighter .toolbar span.title {
-  display: inline !important;
-}
-.syntaxhighlighter .toolbar a {
-  display: block !important;
-  text-align: center !important;
-  text-decoration: none !important;
-  padding-top: 1px !important;
-}
-.syntaxhighlighter .toolbar a.expandSource {
-  display: none !important;
-}
-.syntaxhighlighter.ie {
-  font-size: .9em !important;
-  padding: 1px 0 1px 0 !important;
-}
-.syntaxhighlighter.ie .toolbar {
-  line-height: 8px !important;
-}
-.syntaxhighlighter.ie .toolbar a {
-  padding-top: 0px !important;
-}
-.syntaxhighlighter.printing .line.alt1 .content,
-.syntaxhighlighter.printing .line.alt2 .content,
-.syntaxhighlighter.printing .line.highlighted .number,
-.syntaxhighlighter.printing .line.highlighted.alt1 .content,
-.syntaxhighlighter.printing .line.highlighted.alt2 .content {
-  background: none !important;
-}
-.syntaxhighlighter.printing .line .number {
-  color: #bbbbbb !important;
-}
-.syntaxhighlighter.printing .line .content {
-  color: black !important;
-}
-.syntaxhighlighter.printing .toolbar {
-  display: none !important;
-}
-.syntaxhighlighter.printing a {
-  text-decoration: none !important;
-}
-.syntaxhighlighter.printing .plain, .syntaxhighlighter.printing .plain a {
-  color: black !important;
-}
-.syntaxhighlighter.printing .comments, .syntaxhighlighter.printing .comments a {
-  color: #008200 !important;
-}
-.syntaxhighlighter.printing .string, .syntaxhighlighter.printing .string a {
-  color: blue !important;
-}
-.syntaxhighlighter.printing .keyword {
-  color: #006699 !important;
-  font-weight: bold !important;
-}
-.syntaxhighlighter.printing .preprocessor {
-  color: gray !important;
-}
-.syntaxhighlighter.printing .variable {
-  color: #aa7700 !important;
-}
-.syntaxhighlighter.printing .value {
-  color: #009900 !important;
-}
-.syntaxhighlighter.printing .functions {
-  color: #ff1493 !important;
-}
-.syntaxhighlighter.printing .constants {
-  color: #0066cc !important;
-}
-.syntaxhighlighter.printing .script {
-  font-weight: bold !important;
-}
-.syntaxhighlighter.printing .color1, .syntaxhighlighter.printing .color1 a {
-  color: gray !important;
-}
-.syntaxhighlighter.printing .color2, .syntaxhighlighter.printing .color2 a {
-  color: #ff1493 !important;
-}
-.syntaxhighlighter.printing .color3, .syntaxhighlighter.printing .color3 a {
-  color: red !important;
-}
-.syntaxhighlighter.printing .break, .syntaxhighlighter.printing .break a {
-  color: black !important;
-}
-
-.syntaxhighlighter {
-  background-color: black !important;
-}
-.syntaxhighlighter .line.alt1 {
-  background-color: black !important;
-}
-.syntaxhighlighter .line.alt2 {
-  background-color: black !important;
-}
-.syntaxhighlighter .line.highlighted.alt1, .syntaxhighlighter .line.highlighted.alt2 {
-  background-color: #2a3133 !important;
-}
-.syntaxhighlighter .line.highlighted.number {
-  color: white !important;
-}
-.syntaxhighlighter table caption {
-  color: #d3d3d3 !important;
-}
-.syntaxhighlighter .gutter {
-  color: #d3d3d3 !important;
-}
-.syntaxhighlighter .gutter .line {
-  border-right: 3px solid #990000 !important;
-}
-.syntaxhighlighter .gutter .line.highlighted {
-  background-color: #990000 !important;
-  color: black !important;
-}
-.syntaxhighlighter.printing .line .content {
-  border: none !important;
-}
-.syntaxhighlighter.collapsed {
-  overflow: visible !important;
-}
-.syntaxhighlighter.collapsed .toolbar {
-  color: #ebdb8d !important;
-  background: black !important;
-  border: 1px solid #990000 !important;
-}
-.syntaxhighlighter.collapsed .toolbar a {
-  color: #ebdb8d !important;
-}
-.syntaxhighlighter.collapsed .toolbar a:hover {
-  color: #ff7d27 !important;
-}
-.syntaxhighlighter .toolbar {
-  color: white !important;
-  background: #990000 !important;
-  border: none !important;
-}
-.syntaxhighlighter .toolbar a {
-  color: white !important;
-}
-.syntaxhighlighter .toolbar a:hover {
-  color: #9ccff4 !important;
-}
-.syntaxhighlighter .plain, .syntaxhighlighter .plain a {
-  color: #d3d3d3 !important;
-}
-.syntaxhighlighter .comments, .syntaxhighlighter .comments a {
-  color: #ff7d27 !important;
-}
-.syntaxhighlighter .string, .syntaxhighlighter .string a {
-  color: #ff9e7b !important;
-}
-.syntaxhighlighter .keyword {
-  color: aqua !important;
-}
-.syntaxhighlighter .preprocessor {
-  color: #aec4de !important;
-}
-.syntaxhighlighter .variable {
-  color: #ffaa3e !important;
-}
-.syntaxhighlighter .value {
-  color: #009900 !important;
-}
-.syntaxhighlighter .functions {
-  color: #81cef9 !important;
-}
-.syntaxhighlighter .constants {
-  color: #ff9e7b !important;
-}
-.syntaxhighlighter .script {
-  font-weight: bold !important;
-  color: aqua !important;
-  background-color: none !important;
-}
-.syntaxhighlighter .color1, .syntaxhighlighter .color1 a {
-  color: #ebdb8d !important;
-}
-.syntaxhighlighter .color2, .syntaxhighlighter .color2 a {
-  color: #ff7d27 !important;
-}
-.syntaxhighlighter .color3, .syntaxhighlighter .color3 a {
-  color: #aec4de !important;
-}
diff --git a/guides/assets/stylesheets/syntaxhighlighter/shCoreFadeToGrey.css b/guides/assets/stylesheets/syntaxhighlighter/shCoreFadeToGrey.css
deleted file mode 100644
index 6101eba51f..0000000000
--- a/guides/assets/stylesheets/syntaxhighlighter/shCoreFadeToGrey.css
+++ /dev/null
@@ -1,328 +0,0 @@
-/**
- * SyntaxHighlighter
- * http://alexgorbatchev.com/SyntaxHighlighter
- *
- * SyntaxHighlighter is donationware. If you are using it, please donate.
- * http://alexgorbatchev.com/SyntaxHighlighter/donate.html
- *
- * @version
- * 3.0.83 (July 02 2010)
- * 
- * @copyright
- * Copyright (C) 2004-2010 Alex Gorbatchev.
- *
- * @license
- * Dual licensed under the MIT and GPL licenses.
- */
-.syntaxhighlighter a,
-.syntaxhighlighter div,
-.syntaxhighlighter code,
-.syntaxhighlighter table,
-.syntaxhighlighter table td,
-.syntaxhighlighter table tr,
-.syntaxhighlighter table tbody,
-.syntaxhighlighter table thead,
-.syntaxhighlighter table caption,
-.syntaxhighlighter textarea {
-  -moz-border-radius: 0 0 0 0 !important;
-  -webkit-border-radius: 0 0 0 0 !important;
-  background: none !important;
-  border: 0 !important;
-  bottom: auto !important;
-  float: none !important;
-  height: auto !important;
-  left: auto !important;
-  line-height: 1.1em !important;
-  margin: 0 !important;
-  outline: 0 !important;
-  overflow: visible !important;
-  padding: 0 !important;
-  position: static !important;
-  right: auto !important;
-  text-align: left !important;
-  top: auto !important;
-  vertical-align: baseline !important;
-  width: auto !important;
-  box-sizing: content-box !important;
-  font-family: "Consolas", "Bitstream Vera Sans Mono", "Courier New", Courier, monospace !important;
-  font-weight: normal !important;
-  font-style: normal !important;
-  font-size: 1em !important;
-  min-height: inherit !important;
-  min-height: auto !important;
-}
-
-.syntaxhighlighter {
-  width: 100% !important;
-  margin: 1em 0 1em 0 !important;
-  position: relative !important;
-  overflow: auto !important;
-  font-size: 1em !important;
-}
-.syntaxhighlighter.source {
-  overflow: hidden !important;
-}
-.syntaxhighlighter .bold {
-  font-weight: bold !important;
-}
-.syntaxhighlighter .italic {
-  font-style: italic !important;
-}
-.syntaxhighlighter .line {
-  white-space: pre !important;
-}
-.syntaxhighlighter table {
-  width: 100% !important;
-}
-.syntaxhighlighter table caption {
-  text-align: left !important;
-  padding: .5em 0 0.5em 1em !important;
-}
-.syntaxhighlighter table td.code {
-  width: 100% !important;
-}
-.syntaxhighlighter table td.code .container {
-  position: relative !important;
-}
-.syntaxhighlighter table td.code .container textarea {
-  box-sizing: border-box !important;
-  position: absolute !important;
-  left: 0 !important;
-  top: 0 !important;
-  width: 100% !important;
-  height: 100% !important;
-  border: none !important;
-  background: white !important;
-  padding-left: 1em !important;
-  overflow: hidden !important;
-  white-space: pre !important;
-}
-.syntaxhighlighter table td.gutter .line {
-  text-align: right !important;
-  padding: 0 0.5em 0 1em !important;
-}
-.syntaxhighlighter table td.code .line {
-  padding: 0 1em !important;
-}
-.syntaxhighlighter.nogutter td.code .container textarea, .syntaxhighlighter.nogutter td.code .line {
-  padding-left: 0em !important;
-}
-.syntaxhighlighter.show {
-  display: block !important;
-}
-.syntaxhighlighter.collapsed table {
-  display: none !important;
-}
-.syntaxhighlighter.collapsed .toolbar {
-  padding: 0.1em 0.8em 0em 0.8em !important;
-  font-size: 1em !important;
-  position: static !important;
-  width: auto !important;
-  height: auto !important;
-}
-.syntaxhighlighter.collapsed .toolbar span {
-  display: inline !important;
-  margin-right: 1em !important;
-}
-.syntaxhighlighter.collapsed .toolbar span a {
-  padding: 0 !important;
-  display: none !important;
-}
-.syntaxhighlighter.collapsed .toolbar span a.expandSource {
-  display: inline !important;
-}
-.syntaxhighlighter .toolbar {
-  position: absolute !important;
-  right: 1px !important;
-  top: 1px !important;
-  width: 11px !important;
-  height: 11px !important;
-  font-size: 10px !important;
-  z-index: 10 !important;
-}
-.syntaxhighlighter .toolbar span.title {
-  display: inline !important;
-}
-.syntaxhighlighter .toolbar a {
-  display: block !important;
-  text-align: center !important;
-  text-decoration: none !important;
-  padding-top: 1px !important;
-}
-.syntaxhighlighter .toolbar a.expandSource {
-  display: none !important;
-}
-.syntaxhighlighter.ie {
-  font-size: .9em !important;
-  padding: 1px 0 1px 0 !important;
-}
-.syntaxhighlighter.ie .toolbar {
-  line-height: 8px !important;
-}
-.syntaxhighlighter.ie .toolbar a {
-  padding-top: 0px !important;
-}
-.syntaxhighlighter.printing .line.alt1 .content,
-.syntaxhighlighter.printing .line.alt2 .content,
-.syntaxhighlighter.printing .line.highlighted .number,
-.syntaxhighlighter.printing .line.highlighted.alt1 .content,
-.syntaxhighlighter.printing .line.highlighted.alt2 .content {
-  background: none !important;
-}
-.syntaxhighlighter.printing .line .number {
-  color: #bbbbbb !important;
-}
-.syntaxhighlighter.printing .line .content {
-  color: black !important;
-}
-.syntaxhighlighter.printing .toolbar {
-  display: none !important;
-}
-.syntaxhighlighter.printing a {
-  text-decoration: none !important;
-}
-.syntaxhighlighter.printing .plain, .syntaxhighlighter.printing .plain a {
-  color: black !important;
-}
-.syntaxhighlighter.printing .comments, .syntaxhighlighter.printing .comments a {
-  color: #008200 !important;
-}
-.syntaxhighlighter.printing .string, .syntaxhighlighter.printing .string a {
-  color: blue !important;
-}
-.syntaxhighlighter.printing .keyword {
-  color: #006699 !important;
-  font-weight: bold !important;
-}
-.syntaxhighlighter.printing .preprocessor {
-  color: gray !important;
-}
-.syntaxhighlighter.printing .variable {
-  color: #aa7700 !important;
-}
-.syntaxhighlighter.printing .value {
-  color: #009900 !important;
-}
-.syntaxhighlighter.printing .functions {
-  color: #ff1493 !important;
-}
-.syntaxhighlighter.printing .constants {
-  color: #0066cc !important;
-}
-.syntaxhighlighter.printing .script {
-  font-weight: bold !important;
-}
-.syntaxhighlighter.printing .color1, .syntaxhighlighter.printing .color1 a {
-  color: gray !important;
-}
-.syntaxhighlighter.printing .color2, .syntaxhighlighter.printing .color2 a {
-  color: #ff1493 !important;
-}
-.syntaxhighlighter.printing .color3, .syntaxhighlighter.printing .color3 a {
-  color: red !important;
-}
-.syntaxhighlighter.printing .break, .syntaxhighlighter.printing .break a {
-  color: black !important;
-}
-
-.syntaxhighlighter {
-  background-color: #121212 !important;
-}
-.syntaxhighlighter .line.alt1 {
-  background-color: #121212 !important;
-}
-.syntaxhighlighter .line.alt2 {
-  background-color: #121212 !important;
-}
-.syntaxhighlighter .line.highlighted.alt1, .syntaxhighlighter .line.highlighted.alt2 {
-  background-color: #2c2c29 !important;
-}
-.syntaxhighlighter .line.highlighted.number {
-  color: white !important;
-}
-.syntaxhighlighter table caption {
-  color: white !important;
-}
-.syntaxhighlighter .gutter {
-  color: #afafaf !important;
-}
-.syntaxhighlighter .gutter .line {
-  border-right: 3px solid #3185b9 !important;
-}
-.syntaxhighlighter .gutter .line.highlighted {
-  background-color: #3185b9 !important;
-  color: #121212 !important;
-}
-.syntaxhighlighter.printing .line .content {
-  border: none !important;
-}
-.syntaxhighlighter.collapsed {
-  overflow: visible !important;
-}
-.syntaxhighlighter.collapsed .toolbar {
-  color: #3185b9 !important;
-  background: black !important;
-  border: 1px solid #3185b9 !important;
-}
-.syntaxhighlighter.collapsed .toolbar a {
-  color: #3185b9 !important;
-}
-.syntaxhighlighter.collapsed .toolbar a:hover {
-  color: #d01d33 !important;
-}
-.syntaxhighlighter .toolbar {
-  color: white !important;
-  background: #3185b9 !important;
-  border: none !important;
-}
-.syntaxhighlighter .toolbar a {
-  color: white !important;
-}
-.syntaxhighlighter .toolbar a:hover {
-  color: #96daff !important;
-}
-.syntaxhighlighter .plain, .syntaxhighlighter .plain a {
-  color: white !important;
-}
-.syntaxhighlighter .comments, .syntaxhighlighter .comments a {
-  color: #696854 !important;
-}
-.syntaxhighlighter .string, .syntaxhighlighter .string a {
-  color: #e3e658 !important;
-}
-.syntaxhighlighter .keyword {
-  color: #d01d33 !important;
-}
-.syntaxhighlighter .preprocessor {
-  color: #435a5f !important;
-}
-.syntaxhighlighter .variable {
-  color: #898989 !important;
-}
-.syntaxhighlighter .value {
-  color: #009900 !important;
-}
-.syntaxhighlighter .functions {
-  color: #aaaaaa !important;
-}
-.syntaxhighlighter .constants {
-  color: #96daff !important;
-}
-.syntaxhighlighter .script {
-  font-weight: bold !important;
-  color: #d01d33 !important;
-  background-color: none !important;
-}
-.syntaxhighlighter .color1, .syntaxhighlighter .color1 a {
-  color: #ffc074 !important;
-}
-.syntaxhighlighter .color2, .syntaxhighlighter .color2 a {
-  color: #4a8cdb !important;
-}
-.syntaxhighlighter .color3, .syntaxhighlighter .color3 a {
-  color: #96daff !important;
-}
-
-.syntaxhighlighter .functions {
-  font-weight: bold !important;
-}
diff --git a/guides/assets/stylesheets/syntaxhighlighter/shCoreMDUltra.css b/guides/assets/stylesheets/syntaxhighlighter/shCoreMDUltra.css
deleted file mode 100644
index 2923ce7367..0000000000
--- a/guides/assets/stylesheets/syntaxhighlighter/shCoreMDUltra.css
+++ /dev/null
@@ -1,324 +0,0 @@
-/**
- * SyntaxHighlighter
- * http://alexgorbatchev.com/SyntaxHighlighter
- *
- * SyntaxHighlighter is donationware. If you are using it, please donate.
- * http://alexgorbatchev.com/SyntaxHighlighter/donate.html
- *
- * @version
- * 3.0.83 (July 02 2010)
- * 
- * @copyright
- * Copyright (C) 2004-2010 Alex Gorbatchev.
- *
- * @license
- * Dual licensed under the MIT and GPL licenses.
- */
-.syntaxhighlighter a,
-.syntaxhighlighter div,
-.syntaxhighlighter code,
-.syntaxhighlighter table,
-.syntaxhighlighter table td,
-.syntaxhighlighter table tr,
-.syntaxhighlighter table tbody,
-.syntaxhighlighter table thead,
-.syntaxhighlighter table caption,
-.syntaxhighlighter textarea {
-  -moz-border-radius: 0 0 0 0 !important;
-  -webkit-border-radius: 0 0 0 0 !important;
-  background: none !important;
-  border: 0 !important;
-  bottom: auto !important;
-  float: none !important;
-  height: auto !important;
-  left: auto !important;
-  line-height: 1.1em !important;
-  margin: 0 !important;
-  outline: 0 !important;
-  overflow: visible !important;
-  padding: 0 !important;
-  position: static !important;
-  right: auto !important;
-  text-align: left !important;
-  top: auto !important;
-  vertical-align: baseline !important;
-  width: auto !important;
-  box-sizing: content-box !important;
-  font-family: "Consolas", "Bitstream Vera Sans Mono", "Courier New", Courier, monospace !important;
-  font-weight: normal !important;
-  font-style: normal !important;
-  font-size: 1em !important;
-  min-height: inherit !important;
-  min-height: auto !important;
-}
-
-.syntaxhighlighter {
-  width: 100% !important;
-  margin: 1em 0 1em 0 !important;
-  position: relative !important;
-  overflow: auto !important;
-  font-size: 1em !important;
-}
-.syntaxhighlighter.source {
-  overflow: hidden !important;
-}
-.syntaxhighlighter .bold {
-  font-weight: bold !important;
-}
-.syntaxhighlighter .italic {
-  font-style: italic !important;
-}
-.syntaxhighlighter .line {
-  white-space: pre !important;
-}
-.syntaxhighlighter table {
-  width: 100% !important;
-}
-.syntaxhighlighter table caption {
-  text-align: left !important;
-  padding: .5em 0 0.5em 1em !important;
-}
-.syntaxhighlighter table td.code {
-  width: 100% !important;
-}
-.syntaxhighlighter table td.code .container {
-  position: relative !important;
-}
-.syntaxhighlighter table td.code .container textarea {
-  box-sizing: border-box !important;
-  position: absolute !important;
-  left: 0 !important;
-  top: 0 !important;
-  width: 100% !important;
-  height: 100% !important;
-  border: none !important;
-  background: white !important;
-  padding-left: 1em !important;
-  overflow: hidden !important;
-  white-space: pre !important;
-}
-.syntaxhighlighter table td.gutter .line {
-  text-align: right !important;
-  padding: 0 0.5em 0 1em !important;
-}
-.syntaxhighlighter table td.code .line {
-  padding: 0 1em !important;
-}
-.syntaxhighlighter.nogutter td.code .container textarea, .syntaxhighlighter.nogutter td.code .line {
-  padding-left: 0em !important;
-}
-.syntaxhighlighter.show {
-  display: block !important;
-}
-.syntaxhighlighter.collapsed table {
-  display: none !important;
-}
-.syntaxhighlighter.collapsed .toolbar {
-  padding: 0.1em 0.8em 0em 0.8em !important;
-  font-size: 1em !important;
-  position: static !important;
-  width: auto !important;
-  height: auto !important;
-}
-.syntaxhighlighter.collapsed .toolbar span {
-  display: inline !important;
-  margin-right: 1em !important;
-}
-.syntaxhighlighter.collapsed .toolbar span a {
-  padding: 0 !important;
-  display: none !important;
-}
-.syntaxhighlighter.collapsed .toolbar span a.expandSource {
-  display: inline !important;
-}
-.syntaxhighlighter .toolbar {
-  position: absolute !important;
-  right: 1px !important;
-  top: 1px !important;
-  width: 11px !important;
-  height: 11px !important;
-  font-size: 10px !important;
-  z-index: 10 !important;
-}
-.syntaxhighlighter .toolbar span.title {
-  display: inline !important;
-}
-.syntaxhighlighter .toolbar a {
-  display: block !important;
-  text-align: center !important;
-  text-decoration: none !important;
-  padding-top: 1px !important;
-}
-.syntaxhighlighter .toolbar a.expandSource {
-  display: none !important;
-}
-.syntaxhighlighter.ie {
-  font-size: .9em !important;
-  padding: 1px 0 1px 0 !important;
-}
-.syntaxhighlighter.ie .toolbar {
-  line-height: 8px !important;
-}
-.syntaxhighlighter.ie .toolbar a {
-  padding-top: 0px !important;
-}
-.syntaxhighlighter.printing .line.alt1 .content,
-.syntaxhighlighter.printing .line.alt2 .content,
-.syntaxhighlighter.printing .line.highlighted .number,
-.syntaxhighlighter.printing .line.highlighted.alt1 .content,
-.syntaxhighlighter.printing .line.highlighted.alt2 .content {
-  background: none !important;
-}
-.syntaxhighlighter.printing .line .number {
-  color: #bbbbbb !important;
-}
-.syntaxhighlighter.printing .line .content {
-  color: black !important;
-}
-.syntaxhighlighter.printing .toolbar {
-  display: none !important;
-}
-.syntaxhighlighter.printing a {
-  text-decoration: none !important;
-}
-.syntaxhighlighter.printing .plain, .syntaxhighlighter.printing .plain a {
-  color: black !important;
-}
-.syntaxhighlighter.printing .comments, .syntaxhighlighter.printing .comments a {
-  color: #008200 !important;
-}
-.syntaxhighlighter.printing .string, .syntaxhighlighter.printing .string a {
-  color: blue !important;
-}
-.syntaxhighlighter.printing .keyword {
-  color: #006699 !important;
-  font-weight: bold !important;
-}
-.syntaxhighlighter.printing .preprocessor {
-  color: gray !important;
-}
-.syntaxhighlighter.printing .variable {
-  color: #aa7700 !important;
-}
-.syntaxhighlighter.printing .value {
-  color: #009900 !important;
-}
-.syntaxhighlighter.printing .functions {
-  color: #ff1493 !important;
-}
-.syntaxhighlighter.printing .constants {
-  color: #0066cc !important;
-}
-.syntaxhighlighter.printing .script {
-  font-weight: bold !important;
-}
-.syntaxhighlighter.printing .color1, .syntaxhighlighter.printing .color1 a {
-  color: gray !important;
-}
-.syntaxhighlighter.printing .color2, .syntaxhighlighter.printing .color2 a {
-  color: #ff1493 !important;
-}
-.syntaxhighlighter.printing .color3, .syntaxhighlighter.printing .color3 a {
-  color: red !important;
-}
-.syntaxhighlighter.printing .break, .syntaxhighlighter.printing .break a {
-  color: black !important;
-}
-
-.syntaxhighlighter {
-  background-color: #222222 !important;
-}
-.syntaxhighlighter .line.alt1 {
-  background-color: #222222 !important;
-}
-.syntaxhighlighter .line.alt2 {
-  background-color: #222222 !important;
-}
-.syntaxhighlighter .line.highlighted.alt1, .syntaxhighlighter .line.highlighted.alt2 {
-  background-color: #253e5a !important;
-}
-.syntaxhighlighter .line.highlighted.number {
-  color: white !important;
-}
-.syntaxhighlighter table caption {
-  color: lime !important;
-}
-.syntaxhighlighter .gutter {
-  color: #38566f !important;
-}
-.syntaxhighlighter .gutter .line {
-  border-right: 3px solid #435a5f !important;
-}
-.syntaxhighlighter .gutter .line.highlighted {
-  background-color: #435a5f !important;
-  color: #222222 !important;
-}
-.syntaxhighlighter.printing .line .content {
-  border: none !important;
-}
-.syntaxhighlighter.collapsed {
-  overflow: visible !important;
-}
-.syntaxhighlighter.collapsed .toolbar {
-  color: #428bdd !important;
-  background: black !important;
-  border: 1px solid #435a5f !important;
-}
-.syntaxhighlighter.collapsed .toolbar a {
-  color: #428bdd !important;
-}
-.syntaxhighlighter.collapsed .toolbar a:hover {
-  color: lime !important;
-}
-.syntaxhighlighter .toolbar {
-  color: #aaaaff !important;
-  background: #435a5f !important;
-  border: none !important;
-}
-.syntaxhighlighter .toolbar a {
-  color: #aaaaff !important;
-}
-.syntaxhighlighter .toolbar a:hover {
-  color: #9ccff4 !important;
-}
-.syntaxhighlighter .plain, .syntaxhighlighter .plain a {
-  color: lime !important;
-}
-.syntaxhighlighter .comments, .syntaxhighlighter .comments a {
-  color: #428bdd !important;
-}
-.syntaxhighlighter .string, .syntaxhighlighter .string a {
-  color: lime !important;
-}
-.syntaxhighlighter .keyword {
-  color: #aaaaff !important;
-}
-.syntaxhighlighter .preprocessor {
-  color: #8aa6c1 !important;
-}
-.syntaxhighlighter .variable {
-  color: aqua !important;
-}
-.syntaxhighlighter .value {
-  color: #f7e741 !important;
-}
-.syntaxhighlighter .functions {
-  color: #ff8000 !important;
-}
-.syntaxhighlighter .constants {
-  color: yellow !important;
-}
-.syntaxhighlighter .script {
-  font-weight: bold !important;
-  color: #aaaaff !important;
-  background-color: none !important;
-}
-.syntaxhighlighter .color1, .syntaxhighlighter .color1 a {
-  color: red !important;
-}
-.syntaxhighlighter .color2, .syntaxhighlighter .color2 a {
-  color: yellow !important;
-}
-.syntaxhighlighter .color3, .syntaxhighlighter .color3 a {
-  color: #ffaa3e !important;
-}
diff --git a/guides/assets/stylesheets/syntaxhighlighter/shCoreMidnight.css b/guides/assets/stylesheets/syntaxhighlighter/shCoreMidnight.css
deleted file mode 100644
index e3733eed56..0000000000
--- a/guides/assets/stylesheets/syntaxhighlighter/shCoreMidnight.css
+++ /dev/null
@@ -1,324 +0,0 @@
-/**
- * SyntaxHighlighter
- * http://alexgorbatchev.com/SyntaxHighlighter
- *
- * SyntaxHighlighter is donationware. If you are using it, please donate.
- * http://alexgorbatchev.com/SyntaxHighlighter/donate.html
- *
- * @version
- * 3.0.83 (July 02 2010)
- * 
- * @copyright
- * Copyright (C) 2004-2010 Alex Gorbatchev.
- *
- * @license
- * Dual licensed under the MIT and GPL licenses.
- */
-.syntaxhighlighter a,
-.syntaxhighlighter div,
-.syntaxhighlighter code,
-.syntaxhighlighter table,
-.syntaxhighlighter table td,
-.syntaxhighlighter table tr,
-.syntaxhighlighter table tbody,
-.syntaxhighlighter table thead,
-.syntaxhighlighter table caption,
-.syntaxhighlighter textarea {
-  -moz-border-radius: 0 0 0 0 !important;
-  -webkit-border-radius: 0 0 0 0 !important;
-  background: none !important;
-  border: 0 !important;
-  bottom: auto !important;
-  float: none !important;
-  height: auto !important;
-  left: auto !important;
-  line-height: 1.1em !important;
-  margin: 0 !important;
-  outline: 0 !important;
-  overflow: visible !important;
-  padding: 0 !important;
-  position: static !important;
-  right: auto !important;
-  text-align: left !important;
-  top: auto !important;
-  vertical-align: baseline !important;
-  width: auto !important;
-  box-sizing: content-box !important;
-  font-family: "Consolas", "Bitstream Vera Sans Mono", "Courier New", Courier, monospace !important;
-  font-weight: normal !important;
-  font-style: normal !important;
-  font-size: 1em !important;
-  min-height: inherit !important;
-  min-height: auto !important;
-}
-
-.syntaxhighlighter {
-  width: 100% !important;
-  margin: 1em 0 1em 0 !important;
-  position: relative !important;
-  overflow: auto !important;
-  font-size: 1em !important;
-}
-.syntaxhighlighter.source {
-  overflow: hidden !important;
-}
-.syntaxhighlighter .bold {
-  font-weight: bold !important;
-}
-.syntaxhighlighter .italic {
-  font-style: italic !important;
-}
-.syntaxhighlighter .line {
-  white-space: pre !important;
-}
-.syntaxhighlighter table {
-  width: 100% !important;
-}
-.syntaxhighlighter table caption {
-  text-align: left !important;
-  padding: .5em 0 0.5em 1em !important;
-}
-.syntaxhighlighter table td.code {
-  width: 100% !important;
-}
-.syntaxhighlighter table td.code .container {
-  position: relative !important;
-}
-.syntaxhighlighter table td.code .container textarea {
-  box-sizing: border-box !important;
-  position: absolute !important;
-  left: 0 !important;
-  top: 0 !important;
-  width: 100% !important;
-  height: 100% !important;
-  border: none !important;
-  background: white !important;
-  padding-left: 1em !important;
-  overflow: hidden !important;
-  white-space: pre !important;
-}
-.syntaxhighlighter table td.gutter .line {
-  text-align: right !important;
-  padding: 0 0.5em 0 1em !important;
-}
-.syntaxhighlighter table td.code .line {
-  padding: 0 1em !important;
-}
-.syntaxhighlighter.nogutter td.code .container textarea, .syntaxhighlighter.nogutter td.code .line {
-  padding-left: 0em !important;
-}
-.syntaxhighlighter.show {
-  display: block !important;
-}
-.syntaxhighlighter.collapsed table {
-  display: none !important;
-}
-.syntaxhighlighter.collapsed .toolbar {
-  padding: 0.1em 0.8em 0em 0.8em !important;
-  font-size: 1em !important;
-  position: static !important;
-  width: auto !important;
-  height: auto !important;
-}
-.syntaxhighlighter.collapsed .toolbar span {
-  display: inline !important;
-  margin-right: 1em !important;
-}
-.syntaxhighlighter.collapsed .toolbar span a {
-  padding: 0 !important;
-  display: none !important;
-}
-.syntaxhighlighter.collapsed .toolbar span a.expandSource {
-  display: inline !important;
-}
-.syntaxhighlighter .toolbar {
-  position: absolute !important;
-  right: 1px !important;
-  top: 1px !important;
-  width: 11px !important;
-  height: 11px !important;
-  font-size: 10px !important;
-  z-index: 10 !important;
-}
-.syntaxhighlighter .toolbar span.title {
-  display: inline !important;
-}
-.syntaxhighlighter .toolbar a {
-  display: block !important;
-  text-align: center !important;
-  text-decoration: none !important;
-  padding-top: 1px !important;
-}
-.syntaxhighlighter .toolbar a.expandSource {
-  display: none !important;
-}
-.syntaxhighlighter.ie {
-  font-size: .9em !important;
-  padding: 1px 0 1px 0 !important;
-}
-.syntaxhighlighter.ie .toolbar {
-  line-height: 8px !important;
-}
-.syntaxhighlighter.ie .toolbar a {
-  padding-top: 0px !important;
-}
-.syntaxhighlighter.printing .line.alt1 .content,
-.syntaxhighlighter.printing .line.alt2 .content,
-.syntaxhighlighter.printing .line.highlighted .number,
-.syntaxhighlighter.printing .line.highlighted.alt1 .content,
-.syntaxhighlighter.printing .line.highlighted.alt2 .content {
-  background: none !important;
-}
-.syntaxhighlighter.printing .line .number {
-  color: #bbbbbb !important;
-}
-.syntaxhighlighter.printing .line .content {
-  color: black !important;
-}
-.syntaxhighlighter.printing .toolbar {
-  display: none !important;
-}
-.syntaxhighlighter.printing a {
-  text-decoration: none !important;
-}
-.syntaxhighlighter.printing .plain, .syntaxhighlighter.printing .plain a {
-  color: black !important;
-}
-.syntaxhighlighter.printing .comments, .syntaxhighlighter.printing .comments a {
-  color: #008200 !important;
-}
-.syntaxhighlighter.printing .string, .syntaxhighlighter.printing .string a {
-  color: blue !important;
-}
-.syntaxhighlighter.printing .keyword {
-  color: #006699 !important;
-  font-weight: bold !important;
-}
-.syntaxhighlighter.printing .preprocessor {
-  color: gray !important;
-}
-.syntaxhighlighter.printing .variable {
-  color: #aa7700 !important;
-}
-.syntaxhighlighter.printing .value {
-  color: #009900 !important;
-}
-.syntaxhighlighter.printing .functions {
-  color: #ff1493 !important;
-}
-.syntaxhighlighter.printing .constants {
-  color: #0066cc !important;
-}
-.syntaxhighlighter.printing .script {
-  font-weight: bold !important;
-}
-.syntaxhighlighter.printing .color1, .syntaxhighlighter.printing .color1 a {
-  color: gray !important;
-}
-.syntaxhighlighter.printing .color2, .syntaxhighlighter.printing .color2 a {
-  color: #ff1493 !important;
-}
-.syntaxhighlighter.printing .color3, .syntaxhighlighter.printing .color3 a {
-  color: red !important;
-}
-.syntaxhighlighter.printing .break, .syntaxhighlighter.printing .break a {
-  color: black !important;
-}
-
-.syntaxhighlighter {
-  background-color: #0f192a !important;
-}
-.syntaxhighlighter .line.alt1 {
-  background-color: #0f192a !important;
-}
-.syntaxhighlighter .line.alt2 {
-  background-color: #0f192a !important;
-}
-.syntaxhighlighter .line.highlighted.alt1, .syntaxhighlighter .line.highlighted.alt2 {
-  background-color: #253e5a !important;
-}
-.syntaxhighlighter .line.highlighted.number {
-  color: #38566f !important;
-}
-.syntaxhighlighter table caption {
-  color: #d1edff !important;
-}
-.syntaxhighlighter .gutter {
-  color: #afafaf !important;
-}
-.syntaxhighlighter .gutter .line {
-  border-right: 3px solid #435a5f !important;
-}
-.syntaxhighlighter .gutter .line.highlighted {
-  background-color: #435a5f !important;
-  color: #0f192a !important;
-}
-.syntaxhighlighter.printing .line .content {
-  border: none !important;
-}
-.syntaxhighlighter.collapsed {
-  overflow: visible !important;
-}
-.syntaxhighlighter.collapsed .toolbar {
-  color: #428bdd !important;
-  background: black !important;
-  border: 1px solid #435a5f !important;
-}
-.syntaxhighlighter.collapsed .toolbar a {
-  color: #428bdd !important;
-}
-.syntaxhighlighter.collapsed .toolbar a:hover {
-  color: #1dc116 !important;
-}
-.syntaxhighlighter .toolbar {
-  color: #d1edff !important;
-  background: #435a5f !important;
-  border: none !important;
-}
-.syntaxhighlighter .toolbar a {
-  color: #d1edff !important;
-}
-.syntaxhighlighter .toolbar a:hover {
-  color: #8aa6c1 !important;
-}
-.syntaxhighlighter .plain, .syntaxhighlighter .plain a {
-  color: #d1edff !important;
-}
-.syntaxhighlighter .comments, .syntaxhighlighter .comments a {
-  color: #428bdd !important;
-}
-.syntaxhighlighter .string, .syntaxhighlighter .string a {
-  color: #1dc116 !important;
-}
-.syntaxhighlighter .keyword {
-  color: #b43d3d !important;
-}
-.syntaxhighlighter .preprocessor {
-  color: #8aa6c1 !important;
-}
-.syntaxhighlighter .variable {
-  color: #ffaa3e !important;
-}
-.syntaxhighlighter .value {
-  color: #f7e741 !important;
-}
-.syntaxhighlighter .functions {
-  color: #ffaa3e !important;
-}
-.syntaxhighlighter .constants {
-  color: #e0e8ff !important;
-}
-.syntaxhighlighter .script {
-  font-weight: bold !important;
-  color: #b43d3d !important;
-  background-color: none !important;
-}
-.syntaxhighlighter .color1, .syntaxhighlighter .color1 a {
-  color: #f8bb00 !important;
-}
-.syntaxhighlighter .color2, .syntaxhighlighter .color2 a {
-  color: white !important;
-}
-.syntaxhighlighter .color3, .syntaxhighlighter .color3 a {
-  color: #ffaa3e !important;
-}
diff --git a/guides/assets/stylesheets/syntaxhighlighter/shCoreRDark.css b/guides/assets/stylesheets/syntaxhighlighter/shCoreRDark.css
deleted file mode 100644
index d09368384d..0000000000
--- a/guides/assets/stylesheets/syntaxhighlighter/shCoreRDark.css
+++ /dev/null
@@ -1,324 +0,0 @@
-/**
- * SyntaxHighlighter
- * http://alexgorbatchev.com/SyntaxHighlighter
- *
- * SyntaxHighlighter is donationware. If you are using it, please donate.
- * http://alexgorbatchev.com/SyntaxHighlighter/donate.html
- *
- * @version
- * 3.0.83 (July 02 2010)
- * 
- * @copyright
- * Copyright (C) 2004-2010 Alex Gorbatchev.
- *
- * @license
- * Dual licensed under the MIT and GPL licenses.
- */
-.syntaxhighlighter a,
-.syntaxhighlighter div,
-.syntaxhighlighter code,
-.syntaxhighlighter table,
-.syntaxhighlighter table td,
-.syntaxhighlighter table tr,
-.syntaxhighlighter table tbody,
-.syntaxhighlighter table thead,
-.syntaxhighlighter table caption,
-.syntaxhighlighter textarea {
-  -moz-border-radius: 0 0 0 0 !important;
-  -webkit-border-radius: 0 0 0 0 !important;
-  background: none !important;
-  border: 0 !important;
-  bottom: auto !important;
-  float: none !important;
-  height: auto !important;
-  left: auto !important;
-  line-height: 1.1em !important;
-  margin: 0 !important;
-  outline: 0 !important;
-  overflow: visible !important;
-  padding: 0 !important;
-  position: static !important;
-  right: auto !important;
-  text-align: left !important;
-  top: auto !important;
-  vertical-align: baseline !important;
-  width: auto !important;
-  box-sizing: content-box !important;
-  font-family: "Consolas", "Bitstream Vera Sans Mono", "Courier New", Courier, monospace !important;
-  font-weight: normal !important;
-  font-style: normal !important;
-  font-size: 1em !important;
-  min-height: inherit !important;
-  min-height: auto !important;
-}
-
-.syntaxhighlighter {
-  width: 100% !important;
-  margin: 1em 0 1em 0 !important;
-  position: relative !important;
-  overflow: auto !important;
-  font-size: 1em !important;
-}
-.syntaxhighlighter.source {
-  overflow: hidden !important;
-}
-.syntaxhighlighter .bold {
-  font-weight: bold !important;
-}
-.syntaxhighlighter .italic {
-  font-style: italic !important;
-}
-.syntaxhighlighter .line {
-  white-space: pre !important;
-}
-.syntaxhighlighter table {
-  width: 100% !important;
-}
-.syntaxhighlighter table caption {
-  text-align: left !important;
-  padding: .5em 0 0.5em 1em !important;
-}
-.syntaxhighlighter table td.code {
-  width: 100% !important;
-}
-.syntaxhighlighter table td.code .container {
-  position: relative !important;
-}
-.syntaxhighlighter table td.code .container textarea {
-  box-sizing: border-box !important;
-  position: absolute !important;
-  left: 0 !important;
-  top: 0 !important;
-  width: 100% !important;
-  height: 100% !important;
-  border: none !important;
-  background: white !important;
-  padding-left: 1em !important;
-  overflow: hidden !important;
-  white-space: pre !important;
-}
-.syntaxhighlighter table td.gutter .line {
-  text-align: right !important;
-  padding: 0 0.5em 0 1em !important;
-}
-.syntaxhighlighter table td.code .line {
-  padding: 0 1em !important;
-}
-.syntaxhighlighter.nogutter td.code .container textarea, .syntaxhighlighter.nogutter td.code .line {
-  padding-left: 0em !important;
-}
-.syntaxhighlighter.show {
-  display: block !important;
-}
-.syntaxhighlighter.collapsed table {
-  display: none !important;
-}
-.syntaxhighlighter.collapsed .toolbar {
-  padding: 0.1em 0.8em 0em 0.8em !important;
-  font-size: 1em !important;
-  position: static !important;
-  width: auto !important;
-  height: auto !important;
-}
-.syntaxhighlighter.collapsed .toolbar span {
-  display: inline !important;
-  margin-right: 1em !important;
-}
-.syntaxhighlighter.collapsed .toolbar span a {
-  padding: 0 !important;
-  display: none !important;
-}
-.syntaxhighlighter.collapsed .toolbar span a.expandSource {
-  display: inline !important;
-}
-.syntaxhighlighter .toolbar {
-  position: absolute !important;
-  right: 1px !important;
-  top: 1px !important;
-  width: 11px !important;
-  height: 11px !important;
-  font-size: 10px !important;
-  z-index: 10 !important;
-}
-.syntaxhighlighter .toolbar span.title {
-  display: inline !important;
-}
-.syntaxhighlighter .toolbar a {
-  display: block !important;
-  text-align: center !important;
-  text-decoration: none !important;
-  padding-top: 1px !important;
-}
-.syntaxhighlighter .toolbar a.expandSource {
-  display: none !important;
-}
-.syntaxhighlighter.ie {
-  font-size: .9em !important;
-  padding: 1px 0 1px 0 !important;
-}
-.syntaxhighlighter.ie .toolbar {
-  line-height: 8px !important;
-}
-.syntaxhighlighter.ie .toolbar a {
-  padding-top: 0px !important;
-}
-.syntaxhighlighter.printing .line.alt1 .content,
-.syntaxhighlighter.printing .line.alt2 .content,
-.syntaxhighlighter.printing .line.highlighted .number,
-.syntaxhighlighter.printing .line.highlighted.alt1 .content,
-.syntaxhighlighter.printing .line.highlighted.alt2 .content {
-  background: none !important;
-}
-.syntaxhighlighter.printing .line .number {
-  color: #bbbbbb !important;
-}
-.syntaxhighlighter.printing .line .content {
-  color: black !important;
-}
-.syntaxhighlighter.printing .toolbar {
-  display: none !important;
-}
-.syntaxhighlighter.printing a {
-  text-decoration: none !important;
-}
-.syntaxhighlighter.printing .plain, .syntaxhighlighter.printing .plain a {
-  color: black !important;
-}
-.syntaxhighlighter.printing .comments, .syntaxhighlighter.printing .comments a {
-  color: #008200 !important;
-}
-.syntaxhighlighter.printing .string, .syntaxhighlighter.printing .string a {
-  color: blue !important;
-}
-.syntaxhighlighter.printing .keyword {
-  color: #006699 !important;
-  font-weight: bold !important;
-}
-.syntaxhighlighter.printing .preprocessor {
-  color: gray !important;
-}
-.syntaxhighlighter.printing .variable {
-  color: #aa7700 !important;
-}
-.syntaxhighlighter.printing .value {
-  color: #009900 !important;
-}
-.syntaxhighlighter.printing .functions {
-  color: #ff1493 !important;
-}
-.syntaxhighlighter.printing .constants {
-  color: #0066cc !important;
-}
-.syntaxhighlighter.printing .script {
-  font-weight: bold !important;
-}
-.syntaxhighlighter.printing .color1, .syntaxhighlighter.printing .color1 a {
-  color: gray !important;
-}
-.syntaxhighlighter.printing .color2, .syntaxhighlighter.printing .color2 a {
-  color: #ff1493 !important;
-}
-.syntaxhighlighter.printing .color3, .syntaxhighlighter.printing .color3 a {
-  color: red !important;
-}
-.syntaxhighlighter.printing .break, .syntaxhighlighter.printing .break a {
-  color: black !important;
-}
-
-.syntaxhighlighter {
-  background-color: #1b2426 !important;
-}
-.syntaxhighlighter .line.alt1 {
-  background-color: #1b2426 !important;
-}
-.syntaxhighlighter .line.alt2 {
-  background-color: #1b2426 !important;
-}
-.syntaxhighlighter .line.highlighted.alt1, .syntaxhighlighter .line.highlighted.alt2 {
-  background-color: #323e41 !important;
-}
-.syntaxhighlighter .line.highlighted.number {
-  color: #b9bdb6 !important;
-}
-.syntaxhighlighter table caption {
-  color: #b9bdb6 !important;
-}
-.syntaxhighlighter .gutter {
-  color: #afafaf !important;
-}
-.syntaxhighlighter .gutter .line {
-  border-right: 3px solid #435a5f !important;
-}
-.syntaxhighlighter .gutter .line.highlighted {
-  background-color: #435a5f !important;
-  color: #1b2426 !important;
-}
-.syntaxhighlighter.printing .line .content {
-  border: none !important;
-}
-.syntaxhighlighter.collapsed {
-  overflow: visible !important;
-}
-.syntaxhighlighter.collapsed .toolbar {
-  color: #5ba1cf !important;
-  background: black !important;
-  border: 1px solid #435a5f !important;
-}
-.syntaxhighlighter.collapsed .toolbar a {
-  color: #5ba1cf !important;
-}
-.syntaxhighlighter.collapsed .toolbar a:hover {
-  color: #5ce638 !important;
-}
-.syntaxhighlighter .toolbar {
-  color: white !important;
-  background: #435a5f !important;
-  border: none !important;
-}
-.syntaxhighlighter .toolbar a {
-  color: white !important;
-}
-.syntaxhighlighter .toolbar a:hover {
-  color: #e0e8ff !important;
-}
-.syntaxhighlighter .plain, .syntaxhighlighter .plain a {
-  color: #b9bdb6 !important;
-}
-.syntaxhighlighter .comments, .syntaxhighlighter .comments a {
-  color: #878a85 !important;
-}
-.syntaxhighlighter .string, .syntaxhighlighter .string a {
-  color: #5ce638 !important;
-}
-.syntaxhighlighter .keyword {
-  color: #5ba1cf !important;
-}
-.syntaxhighlighter .preprocessor {
-  color: #435a5f !important;
-}
-.syntaxhighlighter .variable {
-  color: #ffaa3e !important;
-}
-.syntaxhighlighter .value {
-  color: #009900 !important;
-}
-.syntaxhighlighter .functions {
-  color: #ffaa3e !important;
-}
-.syntaxhighlighter .constants {
-  color: #e0e8ff !important;
-}
-.syntaxhighlighter .script {
-  font-weight: bold !important;
-  color: #5ba1cf !important;
-  background-color: none !important;
-}
-.syntaxhighlighter .color1, .syntaxhighlighter .color1 a {
-  color: #e0e8ff !important;
-}
-.syntaxhighlighter .color2, .syntaxhighlighter .color2 a {
-  color: white !important;
-}
-.syntaxhighlighter .color3, .syntaxhighlighter .color3 a {
-  color: #ffaa3e !important;
-}
diff --git a/guides/assets/stylesheets/syntaxhighlighter/shThemeDefault.css b/guides/assets/stylesheets/syntaxhighlighter/shThemeDefault.css
deleted file mode 100644
index 136541172d..0000000000
--- a/guides/assets/stylesheets/syntaxhighlighter/shThemeDefault.css
+++ /dev/null
@@ -1,117 +0,0 @@
-/**
- * SyntaxHighlighter
- * http://alexgorbatchev.com/SyntaxHighlighter
- *
- * SyntaxHighlighter is donationware. If you are using it, please donate.
- * http://alexgorbatchev.com/SyntaxHighlighter/donate.html
- *
- * @version
- * 3.0.83 (July 02 2010)
- * 
- * @copyright
- * Copyright (C) 2004-2010 Alex Gorbatchev.
- *
- * @license
- * Dual licensed under the MIT and GPL licenses.
- */
-.syntaxhighlighter {
-  background-color: white !important;
-}
-.syntaxhighlighter .line.alt1 {
-  background-color: white !important;
-}
-.syntaxhighlighter .line.alt2 {
-  background-color: white !important;
-}
-.syntaxhighlighter .line.highlighted.alt1, .syntaxhighlighter .line.highlighted.alt2 {
-  background-color: #e0e0e0 !important;
-}
-.syntaxhighlighter .line.highlighted.number {
-  color: black !important;
-}
-.syntaxhighlighter table caption {
-  color: black !important;
-}
-.syntaxhighlighter .gutter {
-  color: #afafaf !important;
-}
-.syntaxhighlighter .gutter .line {
-  border-right: 3px solid #6ce26c !important;
-}
-.syntaxhighlighter .gutter .line.highlighted {
-  background-color: #6ce26c !important;
-  color: white !important;
-}
-.syntaxhighlighter.printing .line .content {
-  border: none !important;
-}
-.syntaxhighlighter.collapsed {
-  overflow: visible !important;
-}
-.syntaxhighlighter.collapsed .toolbar {
-  color: blue !important;
-  background: white !important;
-  border: 1px solid #6ce26c !important;
-}
-.syntaxhighlighter.collapsed .toolbar a {
-  color: blue !important;
-}
-.syntaxhighlighter.collapsed .toolbar a:hover {
-  color: red !important;
-}
-.syntaxhighlighter .toolbar {
-  color: white !important;
-  background: #6ce26c !important;
-  border: none !important;
-}
-.syntaxhighlighter .toolbar a {
-  color: white !important;
-}
-.syntaxhighlighter .toolbar a:hover {
-  color: black !important;
-}
-.syntaxhighlighter .plain, .syntaxhighlighter .plain a {
-  color: black !important;
-}
-.syntaxhighlighter .comments, .syntaxhighlighter .comments a {
-  color: #008200 !important;
-}
-.syntaxhighlighter .string, .syntaxhighlighter .string a {
-  color: blue !important;
-}
-.syntaxhighlighter .keyword {
-  color: #006699 !important;
-}
-.syntaxhighlighter .preprocessor {
-  color: gray !important;
-}
-.syntaxhighlighter .variable {
-  color: #aa7700 !important;
-}
-.syntaxhighlighter .value {
-  color: #009900 !important;
-}
-.syntaxhighlighter .functions {
-  color: #ff1493 !important;
-}
-.syntaxhighlighter .constants {
-  color: #0066cc !important;
-}
-.syntaxhighlighter .script {
-  font-weight: bold !important;
-  color: #006699 !important;
-  background-color: none !important;
-}
-.syntaxhighlighter .color1, .syntaxhighlighter .color1 a {
-  color: gray !important;
-}
-.syntaxhighlighter .color2, .syntaxhighlighter .color2 a {
-  color: #ff1493 !important;
-}
-.syntaxhighlighter .color3, .syntaxhighlighter .color3 a {
-  color: red !important;
-}
-
-.syntaxhighlighter .keyword {
-  font-weight: bold !important;
-}
diff --git a/guides/assets/stylesheets/syntaxhighlighter/shThemeDjango.css b/guides/assets/stylesheets/syntaxhighlighter/shThemeDjango.css
deleted file mode 100644
index d8b4313433..0000000000
--- a/guides/assets/stylesheets/syntaxhighlighter/shThemeDjango.css
+++ /dev/null
@@ -1,120 +0,0 @@
-/**
- * SyntaxHighlighter
- * http://alexgorbatchev.com/SyntaxHighlighter
- *
- * SyntaxHighlighter is donationware. If you are using it, please donate.
- * http://alexgorbatchev.com/SyntaxHighlighter/donate.html
- *
- * @version
- * 3.0.83 (July 02 2010)
- * 
- * @copyright
- * Copyright (C) 2004-2010 Alex Gorbatchev.
- *
- * @license
- * Dual licensed under the MIT and GPL licenses.
- */
-.syntaxhighlighter {
-  background-color: #0a2b1d !important;
-}
-.syntaxhighlighter .line.alt1 {
-  background-color: #0a2b1d !important;
-}
-.syntaxhighlighter .line.alt2 {
-  background-color: #0a2b1d !important;
-}
-.syntaxhighlighter .line.highlighted.alt1, .syntaxhighlighter .line.highlighted.alt2 {
-  background-color: #233729 !important;
-}
-.syntaxhighlighter .line.highlighted.number {
-  color: white !important;
-}
-.syntaxhighlighter table caption {
-  color: #f8f8f8 !important;
-}
-.syntaxhighlighter .gutter {
-  color: #497958 !important;
-}
-.syntaxhighlighter .gutter .line {
-  border-right: 3px solid #41a83e !important;
-}
-.syntaxhighlighter .gutter .line.highlighted {
-  background-color: #41a83e !important;
-  color: #0a2b1d !important;
-}
-.syntaxhighlighter.printing .line .content {
-  border: none !important;
-}
-.syntaxhighlighter.collapsed {
-  overflow: visible !important;
-}
-.syntaxhighlighter.collapsed .toolbar {
-  color: #96dd3b !important;
-  background: black !important;
-  border: 1px solid #41a83e !important;
-}
-.syntaxhighlighter.collapsed .toolbar a {
-  color: #96dd3b !important;
-}
-.syntaxhighlighter.collapsed .toolbar a:hover {
-  color: white !important;
-}
-.syntaxhighlighter .toolbar {
-  color: white !important;
-  background: #41a83e !important;
-  border: none !important;
-}
-.syntaxhighlighter .toolbar a {
-  color: white !important;
-}
-.syntaxhighlighter .toolbar a:hover {
-  color: #ffe862 !important;
-}
-.syntaxhighlighter .plain, .syntaxhighlighter .plain a {
-  color: #f8f8f8 !important;
-}
-.syntaxhighlighter .comments, .syntaxhighlighter .comments a {
-  color: #336442 !important;
-}
-.syntaxhighlighter .string, .syntaxhighlighter .string a {
-  color: #9df39f !important;
-}
-.syntaxhighlighter .keyword {
-  color: #96dd3b !important;
-}
-.syntaxhighlighter .preprocessor {
-  color: #91bb9e !important;
-}
-.syntaxhighlighter .variable {
-  color: #ffaa3e !important;
-}
-.syntaxhighlighter .value {
-  color: #f7e741 !important;
-}
-.syntaxhighlighter .functions {
-  color: #ffaa3e !important;
-}
-.syntaxhighlighter .constants {
-  color: #e0e8ff !important;
-}
-.syntaxhighlighter .script {
-  font-weight: bold !important;
-  color: #96dd3b !important;
-  background-color: none !important;
-}
-.syntaxhighlighter .color1, .syntaxhighlighter .color1 a {
-  color: #eb939a !important;
-}
-.syntaxhighlighter .color2, .syntaxhighlighter .color2 a {
-  color: #91bb9e !important;
-}
-.syntaxhighlighter .color3, .syntaxhighlighter .color3 a {
-  color: #edef7d !important;
-}
-
-.syntaxhighlighter .comments {
-  font-style: italic !important;
-}
-.syntaxhighlighter .keyword {
-  font-weight: bold !important;
-}
diff --git a/guides/assets/stylesheets/syntaxhighlighter/shThemeEclipse.css b/guides/assets/stylesheets/syntaxhighlighter/shThemeEclipse.css
deleted file mode 100644
index 77377d9533..0000000000
--- a/guides/assets/stylesheets/syntaxhighlighter/shThemeEclipse.css
+++ /dev/null
@@ -1,128 +0,0 @@
-/**
- * SyntaxHighlighter
- * http://alexgorbatchev.com/SyntaxHighlighter
- *
- * SyntaxHighlighter is donationware. If you are using it, please donate.
- * http://alexgorbatchev.com/SyntaxHighlighter/donate.html
- *
- * @version
- * 3.0.83 (July 02 2010)
- * 
- * @copyright
- * Copyright (C) 2004-2010 Alex Gorbatchev.
- *
- * @license
- * Dual licensed under the MIT and GPL licenses.
- */
-.syntaxhighlighter {
-  background-color: white !important;
-}
-.syntaxhighlighter .line.alt1 {
-  background-color: white !important;
-}
-.syntaxhighlighter .line.alt2 {
-  background-color: white !important;
-}
-.syntaxhighlighter .line.highlighted.alt1, .syntaxhighlighter .line.highlighted.alt2 {
-  background-color: #c3defe !important;
-}
-.syntaxhighlighter .line.highlighted.number {
-  color: white !important;
-}
-.syntaxhighlighter table caption {
-  color: black !important;
-}
-.syntaxhighlighter .gutter {
-  color: #787878 !important;
-}
-.syntaxhighlighter .gutter .line {
-  border-right: 3px solid #d4d0c8 !important;
-}
-.syntaxhighlighter .gutter .line.highlighted {
-  background-color: #d4d0c8 !important;
-  color: white !important;
-}
-.syntaxhighlighter.printing .line .content {
-  border: none !important;
-}
-.syntaxhighlighter.collapsed {
-  overflow: visible !important;
-}
-.syntaxhighlighter.collapsed .toolbar {
-  color: #3f5fbf !important;
-  background: white !important;
-  border: 1px solid #d4d0c8 !important;
-}
-.syntaxhighlighter.collapsed .toolbar a {
-  color: #3f5fbf !important;
-}
-.syntaxhighlighter.collapsed .toolbar a:hover {
-  color: #aa7700 !important;
-}
-.syntaxhighlighter .toolbar {
-  color: #a0a0a0 !important;
-  background: #d4d0c8 !important;
-  border: none !important;
-}
-.syntaxhighlighter .toolbar a {
-  color: #a0a0a0 !important;
-}
-.syntaxhighlighter .toolbar a:hover {
-  color: red !important;
-}
-.syntaxhighlighter .plain, .syntaxhighlighter .plain a {
-  color: black !important;
-}
-.syntaxhighlighter .comments, .syntaxhighlighter .comments a {
-  color: #3f5fbf !important;
-}
-.syntaxhighlighter .string, .syntaxhighlighter .string a {
-  color: #2a00ff !important;
-}
-.syntaxhighlighter .keyword {
-  color: #7f0055 !important;
-}
-.syntaxhighlighter .preprocessor {
-  color: #646464 !important;
-}
-.syntaxhighlighter .variable {
-  color: #aa7700 !important;
-}
-.syntaxhighlighter .value {
-  color: #009900 !important;
-}
-.syntaxhighlighter .functions {
-  color: #ff1493 !important;
-}
-.syntaxhighlighter .constants {
-  color: #0066cc !important;
-}
-.syntaxhighlighter .script {
-  font-weight: bold !important;
-  color: #7f0055 !important;
-  background-color: none !important;
-}
-.syntaxhighlighter .color1, .syntaxhighlighter .color1 a {
-  color: gray !important;
-}
-.syntaxhighlighter .color2, .syntaxhighlighter .color2 a {
-  color: #ff1493 !important;
-}
-.syntaxhighlighter .color3, .syntaxhighlighter .color3 a {
-  color: red !important;
-}
-
-.syntaxhighlighter .keyword {
-  font-weight: bold !important;
-}
-.syntaxhighlighter .xml .keyword {
-  color: #3f7f7f !important;
-  font-weight: normal !important;
-}
-.syntaxhighlighter .xml .color1, .syntaxhighlighter .xml .color1 a {
-  color: #7f007f !important;
-}
-.syntaxhighlighter .xml .string {
-  font-style: italic !important;
-  color: #2a00ff !important;
-}
diff --git a/guides/assets/stylesheets/syntaxhighlighter/shThemeEmacs.css b/guides/assets/stylesheets/syntaxhighlighter/shThemeEmacs.css
deleted file mode 100644
index dae5053fea..0000000000
--- a/guides/assets/stylesheets/syntaxhighlighter/shThemeEmacs.css
+++ /dev/null
@@ -1,113 +0,0 @@
-/**
- * SyntaxHighlighter
- * http://alexgorbatchev.com/SyntaxHighlighter
- *
- * SyntaxHighlighter is donationware. If you are using it, please donate.
- * http://alexgorbatchev.com/SyntaxHighlighter/donate.html
- *
- * @version
- * 3.0.83 (July 02 2010)
- * 
- * @copyright
- * Copyright (C) 2004-2010 Alex Gorbatchev.
- *
- * @license
- * Dual licensed under the MIT and GPL licenses.
- */
-.syntaxhighlighter {
-  background-color: black !important;
-}
-.syntaxhighlighter .line.alt1 {
-  background-color: black !important;
-}
-.syntaxhighlighter .line.alt2 {
-  background-color: black !important;
-}
-.syntaxhighlighter .line.highlighted.alt1, .syntaxhighlighter .line.highlighted.alt2 {
-  background-color: #2a3133 !important;
-}
-.syntaxhighlighter .line.highlighted.number {
-  color: white !important;
-}
-.syntaxhighlighter table caption {
-  color: #d3d3d3 !important;
-}
-.syntaxhighlighter .gutter {
-  color: #d3d3d3 !important;
-}
-.syntaxhighlighter .gutter .line {
-  border-right: 3px solid #990000 !important;
-}
-.syntaxhighlighter .gutter .line.highlighted {
-  background-color: #990000 !important;
-  color: black !important;
-}
-.syntaxhighlighter.printing .line .content {
-  border: none !important;
-}
-.syntaxhighlighter.collapsed {
-  overflow: visible !important;
-}
-.syntaxhighlighter.collapsed .toolbar {
-  color: #ebdb8d !important;
-  background: black !important;
-  border: 1px solid #990000 !important;
-}
-.syntaxhighlighter.collapsed .toolbar a {
-  color: #ebdb8d !important;
-}
-.syntaxhighlighter.collapsed .toolbar a:hover {
-  color: #ff7d27 !important;
-}
-.syntaxhighlighter .toolbar {
-  color: white !important;
-  background: #990000 !important;
-  border: none !important;
-}
-.syntaxhighlighter .toolbar a {
-  color: white !important;
-}
-.syntaxhighlighter .toolbar a:hover {
-  color: #9ccff4 !important;
-}
-.syntaxhighlighter .plain, .syntaxhighlighter .plain a {
-  color: #d3d3d3 !important;
-}
-.syntaxhighlighter .comments, .syntaxhighlighter .comments a {
-  color: #ff7d27 !important;
-}
-.syntaxhighlighter .string, .syntaxhighlighter .string a {
-  color: #ff9e7b !important;
-}
-.syntaxhighlighter .keyword {
-  color: aqua !important;
-}
-.syntaxhighlighter .preprocessor {
-  color: #aec4de !important;
-}
-.syntaxhighlighter .variable {
-  color: #ffaa3e !important;
-}
-.syntaxhighlighter .value {
-  color: #009900 !important;
-}
-.syntaxhighlighter .functions {
-  color: #81cef9 !important;
-}
-.syntaxhighlighter .constants {
-  color: #ff9e7b !important;
-}
-.syntaxhighlighter .script {
-  font-weight: bold !important;
-  color: aqua !important;
-  background-color: none !important;
-}
-.syntaxhighlighter .color1, .syntaxhighlighter .color1 a {
-  color: #ebdb8d !important;
-}
-.syntaxhighlighter .color2, .syntaxhighlighter .color2 a {
-  color: #ff7d27 !important;
-}
-.syntaxhighlighter .color3, .syntaxhighlighter .color3 a {
-  color: #aec4de !important;
-}
diff --git a/guides/assets/stylesheets/syntaxhighlighter/shThemeFadeToGrey.css b/guides/assets/stylesheets/syntaxhighlighter/shThemeFadeToGrey.css
deleted file mode 100644
index 8fbd871fb5..0000000000
--- a/guides/assets/stylesheets/syntaxhighlighter/shThemeFadeToGrey.css
+++ /dev/null
@@ -1,117 +0,0 @@
-/**
- * SyntaxHighlighter
- * http://alexgorbatchev.com/SyntaxHighlighter
- *
- * SyntaxHighlighter is donationware. If you are using it, please donate.
- * http://alexgorbatchev.com/SyntaxHighlighter/donate.html
- *
- * @version
- * 3.0.83 (July 02 2010)
- * 
- * @copyright
- * Copyright (C) 2004-2010 Alex Gorbatchev.
- *
- * @license
- * Dual licensed under the MIT and GPL licenses.
- */
-.syntaxhighlighter {
-  background-color: #121212 !important;
-}
-.syntaxhighlighter .line.alt1 {
-  background-color: #121212 !important;
-}
-.syntaxhighlighter .line.alt2 {
-  background-color: #121212 !important;
-}
-.syntaxhighlighter .line.highlighted.alt1, .syntaxhighlighter .line.highlighted.alt2 {
-  background-color: #2c2c29 !important;
-}
-.syntaxhighlighter .line.highlighted.number {
-  color: white !important;
-}
-.syntaxhighlighter table caption {
-  color: white !important;
-}
-.syntaxhighlighter .gutter {
-  color: #afafaf !important;
-}
-.syntaxhighlighter .gutter .line {
-  border-right: 3px solid #3185b9 !important;
-}
-.syntaxhighlighter .gutter .line.highlighted {
-  background-color: #3185b9 !important;
-  color: #121212 !important;
-}
-.syntaxhighlighter.printing .line .content {
-  border: none !important;
-}
-.syntaxhighlighter.collapsed {
-  overflow: visible !important;
-}
-.syntaxhighlighter.collapsed .toolbar {
-  color: #3185b9 !important;
-  background: black !important;
-  border: 1px solid #3185b9 !important;
-}
-.syntaxhighlighter.collapsed .toolbar a {
-  color: #3185b9 !important;
-}
-.syntaxhighlighter.collapsed .toolbar a:hover {
-  color: #d01d33 !important;
-}
-.syntaxhighlighter .toolbar {
-  color: white !important;
-  background: #3185b9 !important;
-  border: none !important;
-}
-.syntaxhighlighter .toolbar a {
-  color: white !important;
-}
-.syntaxhighlighter .toolbar a:hover {
-  color: #96daff !important;
-}
-.syntaxhighlighter .plain, .syntaxhighlighter .plain a {
-  color: white !important;
-}
-.syntaxhighlighter .comments, .syntaxhighlighter .comments a {
-  color: #696854 !important;
-}
-.syntaxhighlighter .string, .syntaxhighlighter .string a {
-  color: #e3e658 !important;
-}
-.syntaxhighlighter .keyword {
-  color: #d01d33 !important;
-}
-.syntaxhighlighter .preprocessor {
-  color: #435a5f !important;
-}
-.syntaxhighlighter .variable {
-  color: #898989 !important;
-}
-.syntaxhighlighter .value {
-  color: #009900 !important;
-}
-.syntaxhighlighter .functions {
-  color: #aaaaaa !important;
-}
-.syntaxhighlighter .constants {
-  color: #96daff !important;
-}
-.syntaxhighlighter .script {
-  font-weight: bold !important;
-  color: #d01d33 !important;
-  background-color: none !important;
-}
-.syntaxhighlighter .color1, .syntaxhighlighter .color1 a {
-  color: #ffc074 !important;
-}
-.syntaxhighlighter .color2, .syntaxhighlighter .color2 a {
-  color: #4a8cdb !important;
-}
-.syntaxhighlighter .color3, .syntaxhighlighter .color3 a {
-  color: #96daff !important;
-}
-
-.syntaxhighlighter .functions {
-  font-weight: bold !important;
-}
diff --git a/guides/assets/stylesheets/syntaxhighlighter/shThemeMDUltra.css b/guides/assets/stylesheets/syntaxhighlighter/shThemeMDUltra.css
deleted file mode 100755
index f4db39cd83..0000000000
--- a/guides/assets/stylesheets/syntaxhighlighter/shThemeMDUltra.css
+++ /dev/null
@@ -1,113 +0,0 @@
-/**
- * SyntaxHighlighter
- * http://alexgorbatchev.com/SyntaxHighlighter
- *
- * SyntaxHighlighter is donationware. If you are using it, please donate.
- * http://alexgorbatchev.com/SyntaxHighlighter/donate.html
- *
- * @version
- * 3.0.83 (July 02 2010)
- * 
- * @copyright
- * Copyright (C) 2004-2010 Alex Gorbatchev.
- *
- * @license
- * Dual licensed under the MIT and GPL licenses.
- */
-.syntaxhighlighter {
-  background-color: #222222 !important;
-}
-.syntaxhighlighter .line.alt1 {
-  background-color: #222222 !important;
-}
-.syntaxhighlighter .line.alt2 {
-  background-color: #222222 !important;
-}
-.syntaxhighlighter .line.highlighted.alt1, .syntaxhighlighter .line.highlighted.alt2 {
-  background-color: #253e5a !important;
-}
-.syntaxhighlighter .line.highlighted.number {
-  color: white !important;
-}
-.syntaxhighlighter table caption {
-  color: lime !important;
-}
-.syntaxhighlighter .gutter {
-  color: #38566f !important;
-}
-.syntaxhighlighter .gutter .line {
-  border-right: 3px solid #435a5f !important;
-}
-.syntaxhighlighter .gutter .line.highlighted {
-  background-color: #435a5f !important;
-  color: #222222 !important;
-}
-.syntaxhighlighter.printing .line .content {
-  border: none !important;
-}
-.syntaxhighlighter.collapsed {
-  overflow: visible !important;
-}
-.syntaxhighlighter.collapsed .toolbar {
-  color: #428bdd !important;
-  background: black !important;
-  border: 1px solid #435a5f !important;
-}
-.syntaxhighlighter.collapsed .toolbar a {
-  color: #428bdd !important;
-}
-.syntaxhighlighter.collapsed .toolbar a:hover {
-  color: lime !important;
-}
-.syntaxhighlighter .toolbar {
-  color: #aaaaff !important;
-  background: #435a5f !important;
-  border: none !important;
-}
-.syntaxhighlighter .toolbar a {
-  color: #aaaaff !important;
-}
-.syntaxhighlighter .toolbar a:hover {
-  color: #9ccff4 !important;
-}
-.syntaxhighlighter .plain, .syntaxhighlighter .plain a {
-  color: lime !important;
-}
-.syntaxhighlighter .comments, .syntaxhighlighter .comments a {
-  color: #428bdd !important;
-}
-.syntaxhighlighter .string, .syntaxhighlighter .string a {
-  color: lime !important;
-}
-.syntaxhighlighter .keyword {
-  color: #aaaaff !important;
-}
-.syntaxhighlighter .preprocessor {
-  color: #8aa6c1 !important;
-}
-.syntaxhighlighter .variable {
-  color: aqua !important;
-}
-.syntaxhighlighter .value {
-  color: #f7e741 !important;
-}
-.syntaxhighlighter .functions {
-  color: #ff8000 !important;
-}
-.syntaxhighlighter .constants {
-  color: yellow !important;
-}
-.syntaxhighlighter .script {
-  font-weight: bold !important;
-  color: #aaaaff !important;
-  background-color: none !important;
-}
-.syntaxhighlighter .color1, .syntaxhighlighter .color1 a {
-  color: red !important;
-}
-.syntaxhighlighter .color2, .syntaxhighlighter .color2 a {
-  color: yellow !important;
-}
-.syntaxhighlighter .color3, .syntaxhighlighter .color3 a {
-  color: #ffaa3e !important;
-}
diff --git a/guides/assets/stylesheets/syntaxhighlighter/shThemeMidnight.css b/guides/assets/stylesheets/syntaxhighlighter/shThemeMidnight.css
deleted file mode 100644
index c49563cc9d..0000000000
--- a/guides/assets/stylesheets/syntaxhighlighter/shThemeMidnight.css
+++ /dev/null
@@ -1,113 +0,0 @@
-/**
- * SyntaxHighlighter
- * http://alexgorbatchev.com/SyntaxHighlighter
- *
- * SyntaxHighlighter is donationware. If you are using it, please donate.
- * http://alexgorbatchev.com/SyntaxHighlighter/donate.html
- *
- * @version
- * 3.0.83 (July 02 2010)
- * 
- * @copyright
- * Copyright (C) 2004-2010 Alex Gorbatchev.
- *
- * @license
- * Dual licensed under the MIT and GPL licenses.
- */
-.syntaxhighlighter {
-  background-color: #0f192a !important;
-}
-.syntaxhighlighter .line.alt1 {
-  background-color: #0f192a !important;
-}
-.syntaxhighlighter .line.alt2 {
-  background-color: #0f192a !important;
-}
-.syntaxhighlighter .line.highlighted.alt1, .syntaxhighlighter .line.highlighted.alt2 {
-  background-color: #253e5a !important;
-}
-.syntaxhighlighter .line.highlighted.number {
-  color: #38566f !important;
-}
-.syntaxhighlighter table caption {
-  color: #d1edff !important;
-}
-.syntaxhighlighter .gutter {
-  color: #afafaf !important;
-}
-.syntaxhighlighter .gutter .line {
-  border-right: 3px solid #435a5f !important;
-}
-.syntaxhighlighter .gutter .line.highlighted {
-  background-color: #435a5f !important;
-  color: #0f192a !important;
-}
-.syntaxhighlighter.printing .line .content {
-  border: none !important;
-}
-.syntaxhighlighter.collapsed {
-  overflow: visible !important;
-}
-.syntaxhighlighter.collapsed .toolbar {
-  color: #428bdd !important;
-  background: black !important;
-  border: 1px solid #435a5f !important;
-}
-.syntaxhighlighter.collapsed .toolbar a {
-  color: #428bdd !important;
-}
-.syntaxhighlighter.collapsed .toolbar a:hover {
-  color: #1dc116 !important;
-}
-.syntaxhighlighter .toolbar {
-  color: #d1edff !important;
-  background: #435a5f !important;
-  border: none !important;
-}
-.syntaxhighlighter .toolbar a {
-  color: #d1edff !important;
-}
-.syntaxhighlighter .toolbar a:hover {
-  color: #8aa6c1 !important;
-}
-.syntaxhighlighter .plain, .syntaxhighlighter .plain a {
-  color: #d1edff !important;
-}
-.syntaxhighlighter .comments, .syntaxhighlighter .comments a {
-  color: #428bdd !important;
-}
-.syntaxhighlighter .string, .syntaxhighlighter .string a {
-  color: #1dc116 !important;
-}
-.syntaxhighlighter .keyword {
-  color: #b43d3d !important;
-}
-.syntaxhighlighter .preprocessor {
-  color: #8aa6c1 !important;
-}
-.syntaxhighlighter .variable {
-  color: #ffaa3e !important;
-}
-.syntaxhighlighter .value {
-  color: #f7e741 !important;
-}
-.syntaxhighlighter .functions {
-  color: #ffaa3e !important;
-}
-.syntaxhighlighter .constants {
-  color: #e0e8ff !important;
-}
-.syntaxhighlighter .script {
-  font-weight: bold !important;
-  color: #b43d3d !important;
-  background-color: none !important;
-}
-.syntaxhighlighter .color1, .syntaxhighlighter .color1 a {
-  color: #f8bb00 !important;
-}
-.syntaxhighlighter .color2, .syntaxhighlighter .color2 a {
-  color: white !important;
-}
-.syntaxhighlighter .color3, .syntaxhighlighter .color3 a {
-  color: #ffaa3e !important;
-}
diff --git a/guides/assets/stylesheets/syntaxhighlighter/shThemeRDark.css b/guides/assets/stylesheets/syntaxhighlighter/shThemeRDark.css
deleted file mode 100644
index 6305a10e4e..0000000000
--- a/guides/assets/stylesheets/syntaxhighlighter/shThemeRDark.css
+++ /dev/null
@@ -1,113 +0,0 @@
-/**
- * SyntaxHighlighter
- * http://alexgorbatchev.com/SyntaxHighlighter
- *
- * SyntaxHighlighter is donationware. If you are using it, please donate.
- * http://alexgorbatchev.com/SyntaxHighlighter/donate.html
- *
- * @version
- * 3.0.83 (July 02 2010)
- * 
- * @copyright
- * Copyright (C) 2004-2010 Alex Gorbatchev.
- *
- * @license
- * Dual licensed under the MIT and GPL licenses.
- */
-.syntaxhighlighter {
-  background-color: #1b2426 !important;
-}
-.syntaxhighlighter .line.alt1 {
-  background-color: #1b2426 !important;
-}
-.syntaxhighlighter .line.alt2 {
-  background-color: #1b2426 !important;
-}
-.syntaxhighlighter .line.highlighted.alt1, .syntaxhighlighter .line.highlighted.alt2 {
-  background-color: #323e41 !important;
-}
-.syntaxhighlighter .line.highlighted.number {
-  color: #b9bdb6 !important;
-}
-.syntaxhighlighter table caption {
-  color: #b9bdb6 !important;
-}
-.syntaxhighlighter .gutter {
-  color: #afafaf !important;
-}
-.syntaxhighlighter .gutter .line {
-  border-right: 3px solid #435a5f !important;
-}
-.syntaxhighlighter .gutter .line.highlighted {
-  background-color: #435a5f !important;
-  color: #1b2426 !important;
-}
-.syntaxhighlighter.printing .line .content {
-  border: none !important;
-}
-.syntaxhighlighter.collapsed {
-  overflow: visible !important;
-}
-.syntaxhighlighter.collapsed .toolbar {
-  color: #5ba1cf !important;
-  background: black !important;
-  border: 1px solid #435a5f !important;
-}
-.syntaxhighlighter.collapsed .toolbar a {
-  color: #5ba1cf !important;
-}
-.syntaxhighlighter.collapsed .toolbar a:hover {
-  color: #5ce638 !important;
-}
-.syntaxhighlighter .toolbar {
-  color: white !important;
-  background: #435a5f !important;
-  border: none !important;
-}
-.syntaxhighlighter .toolbar a {
-  color: white !important;
-}
-.syntaxhighlighter .toolbar a:hover {
-  color: #e0e8ff !important;
-}
-.syntaxhighlighter .plain, .syntaxhighlighter .plain a {
-  color: #b9bdb6 !important;
-}
-.syntaxhighlighter .comments, .syntaxhighlighter .comments a {
-  color: #878a85 !important;
-}
-.syntaxhighlighter .string, .syntaxhighlighter .string a {
-  color: #5ce638 !important;
-}
-.syntaxhighlighter .keyword {
-  color: #5ba1cf !important;
-}
-.syntaxhighlighter .preprocessor {
-  color: #435a5f !important;
-}
-.syntaxhighlighter .variable {
-  color: #ffaa3e !important;
-}
-.syntaxhighlighter .value {
-  color: #009900 !important;
-}
-.syntaxhighlighter .functions {
-  color: #ffaa3e !important;
-}
-.syntaxhighlighter .constants {
-  color: #e0e8ff !important;
-}
-.syntaxhighlighter .script {
-  font-weight: bold !important;
-  color: #5ba1cf !important;
-  background-color: none !important;
-}
-.syntaxhighlighter .color1, .syntaxhighlighter .color1 a {
-  color: #e0e8ff !important;
-}
-.syntaxhighlighter .color2, .syntaxhighlighter .color2 a {
-  color: white !important;
-}
-.syntaxhighlighter .color3, .syntaxhighlighter .color3 a {
-  color: #ffaa3e !important;
-}
diff --git a/guides/bug_report_templates/action_controller_gem.rb b/guides/bug_report_templates/action_controller_gem.rb
index 604cf4be41..557b1d7bef 100644
--- a/guides/bug_report_templates/action_controller_gem.rb
+++ b/guides/bug_report_templates/action_controller_gem.rb
@@ -1,30 +1,34 @@
+# frozen_string_literal: true
+
 begin
-  require 'bundler/inline'
+  require "bundler/inline"
 rescue LoadError => e
-  $stderr.puts 'Bundler version 1.10 or later is required. Please update your Bundler'
+  $stderr.puts "Bundler version 1.10 or later is required. Please update your Bundler"
   raise e
 end
 
 gemfile(true) do
-  source 'https://rubygems.org'
+  source "https://rubygems.org"
+
+  git_source(:github) { |repo| "https://github.com/#{repo}.git" }
+
   # Activate the gem you are reporting the issue against.
-  gem 'rails', '5.0.0.rc1'
+  gem "rails", "5.1.0"
 end
 
-require 'rack/test'
-require 'action_controller/railtie'
+require "rack/test"
+require "action_controller/railtie"
 
 class TestApp < Rails::Application
-  config.root = File.dirname(__FILE__)
-  config.session_store :cookie_store, key: 'cookie_store_key'
-  secrets.secret_token    = 'secret_token'
-  secrets.secret_key_base = 'secret_key_base'
+  config.root = __dir__
+  config.session_store :cookie_store, key: "cookie_store_key"
+  secrets.secret_key_base = "secret_key_base"
 
   config.logger = Logger.new($stdout)
   Rails.logger  = config.logger
 
   routes.draw do
-    get '/' => 'test#index'
+    get "/" => "test#index"
   end
 end
 
@@ -32,11 +36,11 @@ class TestController < ActionController::Base
   include Rails.application.routes.url_helpers
 
   def index
-    render plain: 'Home'
+    render plain: "Home"
   end
 end
 
-require 'minitest/autorun'
+require "minitest/autorun"
 
 # Ensure backward compatibility with Minitest 4
 Minitest::Test = MiniTest::Unit::TestCase unless defined?(Minitest::Test)
@@ -45,7 +49,7 @@ class BugTest < Minitest::Test
   include Rack::Test::Methods
 
   def test_returns_success
-    get '/'
+    get "/"
     assert last_response.ok?
   end
 
diff --git a/guides/bug_report_templates/action_controller_master.rb b/guides/bug_report_templates/action_controller_master.rb
index 8322707495..ffd81c0079 100644
--- a/guides/bug_report_templates/action_controller_master.rb
+++ b/guides/bug_report_templates/action_controller_master.rb
@@ -1,28 +1,31 @@
+# frozen_string_literal: true
+
 begin
-  require 'bundler/inline'
+  require "bundler/inline"
 rescue LoadError => e
-  $stderr.puts 'Bundler version 1.10 or later is required. Please update your Bundler'
+  $stderr.puts "Bundler version 1.10 or later is required. Please update your Bundler"
   raise e
 end
 
 gemfile(true) do
-  source 'https://rubygems.org'
-  gem 'rails', github: 'rails/rails'
+  source "https://rubygems.org"
+
+  git_source(:github) { |repo| "https://github.com/#{repo}.git" }
+
+  gem "rails", github: "rails/rails"
 end
 
-require 'action_controller/railtie'
+require "action_controller/railtie"
 
 class TestApp < Rails::Application
-  config.root = File.dirname(__FILE__)
-  config.session_store :cookie_store, key: 'cookie_store_key'
-  secrets.secret_token    = 'secret_token'
-  secrets.secret_key_base = 'secret_key_base'
+  config.root = __dir__
+  secrets.secret_key_base = "secret_key_base"
 
   config.logger = Logger.new($stdout)
   Rails.logger  = config.logger
 
   routes.draw do
-    get '/' => 'test#index'
+    get "/" => "test#index"
   end
 end
 
@@ -30,18 +33,18 @@ class TestController < ActionController::Base
   include Rails.application.routes.url_helpers
 
   def index
-    render plain: 'Home'
+    render plain: "Home"
   end
 end
 
-require 'minitest/autorun'
-require 'rack/test'
+require "minitest/autorun"
+require "rack/test"
 
 class BugTest < Minitest::Test
   include Rack::Test::Methods
 
   def test_returns_success
-    get '/'
+    get "/"
     assert last_response.ok?
   end
 
diff --git a/guides/bug_report_templates/active_job_gem.rb b/guides/bug_report_templates/active_job_gem.rb
new file mode 100644
index 0000000000..013d1f8602
--- /dev/null
+++ b/guides/bug_report_templates/active_job_gem.rb
@@ -0,0 +1,37 @@
+# frozen_string_literal: true
+
+begin
+  require "bundler/inline"
+rescue LoadError => e
+  $stderr.puts "Bundler version 1.10 or later is required. Please update your Bundler"
+  raise e
+end
+
+gemfile(true) do
+  source "https://rubygems.org"
+
+  git_source(:github) { |repo| "https://github.com/#{repo}.git" }
+
+  # Activate the gem you are reporting the issue against.
+  gem "activejob", "5.1.0"
+end
+
+require "minitest/autorun"
+require "active_job"
+
+# Ensure backward compatibility with Minitest 4
+Minitest::Test = MiniTest::Unit::TestCase unless defined?(Minitest::Test)
+
+class BuggyJob < ActiveJob::Base
+  def perform
+    puts "performed"
+  end
+end
+
+class BuggyJobTest < ActiveJob::TestCase
+  def test_stuff
+    assert_enqueued_with(job: BuggyJob) do
+      BuggyJob.perform_later
+    end
+  end
+end
diff --git a/guides/bug_report_templates/active_job_master.rb b/guides/bug_report_templates/active_job_master.rb
new file mode 100644
index 0000000000..4bcee07607
--- /dev/null
+++ b/guides/bug_report_templates/active_job_master.rb
@@ -0,0 +1,36 @@
+# frozen_string_literal: true
+
+begin
+  require "bundler/inline"
+rescue LoadError => e
+  $stderr.puts "Bundler version 1.10 or later is required. Please update your Bundler"
+  raise e
+end
+
+gemfile(true) do
+  source "https://rubygems.org"
+
+  git_source(:github) { |repo| "https://github.com/#{repo}.git" }
+
+  gem "rails", github: "rails/rails"
+end
+
+require "active_job"
+require "minitest/autorun"
+
+# Ensure backward compatibility with Minitest 4
+Minitest::Test = MiniTest::Unit::TestCase unless defined?(Minitest::Test)
+
+class BuggyJob < ActiveJob::Base
+  def perform
+    puts "performed"
+  end
+end
+
+class BuggyJobTest < ActiveJob::TestCase
+  def test_stuff
+    assert_enqueued_with(job: BuggyJob) do
+      BuggyJob.perform_later
+    end
+  end
+end
diff --git a/guides/bug_report_templates/active_record_gem.rb b/guides/bug_report_templates/active_record_gem.rb
index d4ede4e2c1..921917fbe9 100644
--- a/guides/bug_report_templates/active_record_gem.rb
+++ b/guides/bug_report_templates/active_record_gem.rb
@@ -1,26 +1,31 @@
+# frozen_string_literal: true
+
 begin
-  require 'bundler/inline'
+  require "bundler/inline"
 rescue LoadError => e
-  $stderr.puts 'Bundler version 1.10 or later is required. Please update your Bundler'
+  $stderr.puts "Bundler version 1.10 or later is required. Please update your Bundler"
   raise e
 end
 
 gemfile(true) do
-  source 'https://rubygems.org'
+  source "https://rubygems.org"
+
+  git_source(:github) { |repo| "https://github.com/#{repo}.git" }
+
   # Activate the gem you are reporting the issue against.
-  gem 'activerecord', '5.0.0.rc1'
-  gem 'sqlite3'
+  gem "activerecord", "5.1.0"
+  gem "sqlite3"
 end
 
-require 'active_record'
-require 'minitest/autorun'
-require 'logger'
+require "active_record"
+require "minitest/autorun"
+require "logger"
 
 # Ensure backward compatibility with Minitest 4
 Minitest::Test = MiniTest::Unit::TestCase unless defined?(Minitest::Test)
 
 # This connection will do for database-independent bug reports.
-ActiveRecord::Base.establish_connection(adapter: 'sqlite3', database: ':memory:')
+ActiveRecord::Base.establish_connection(adapter: "sqlite3", database: ":memory:")
 ActiveRecord::Base.logger = Logger.new(STDOUT)
 
 ActiveRecord::Schema.define do
diff --git a/guides/bug_report_templates/active_record_master.rb b/guides/bug_report_templates/active_record_master.rb
index 6fd401bd50..914f04f51a 100644
--- a/guides/bug_report_templates/active_record_master.rb
+++ b/guides/bug_report_templates/active_record_master.rb
@@ -1,22 +1,27 @@
+# frozen_string_literal: true
+
 begin
-  require 'bundler/inline'
+  require "bundler/inline"
 rescue LoadError => e
-  $stderr.puts 'Bundler version 1.10 or later is required. Please update your Bundler'
+  $stderr.puts "Bundler version 1.10 or later is required. Please update your Bundler"
   raise e
 end
 
 gemfile(true) do
-  source 'https://rubygems.org'
-  gem 'rails', github: 'rails/rails'
-  gem 'sqlite3'
+  source "https://rubygems.org"
+
+  git_source(:github) { |repo| "https://github.com/#{repo}.git" }
+
+  gem "rails", github: "rails/rails"
+  gem "sqlite3"
 end
 
-require 'active_record'
-require 'minitest/autorun'
-require 'logger'
+require "active_record"
+require "minitest/autorun"
+require "logger"
 
 # This connection will do for database-independent bug reports.
-ActiveRecord::Base.establish_connection(adapter: 'sqlite3', database: ':memory:')
+ActiveRecord::Base.establish_connection(adapter: "sqlite3", database: ":memory:")
 ActiveRecord::Base.logger = Logger.new(STDOUT)
 
 ActiveRecord::Schema.define do
diff --git a/guides/bug_report_templates/active_record_migrations_gem.rb b/guides/bug_report_templates/active_record_migrations_gem.rb
new file mode 100644
index 0000000000..9002b8f428
--- /dev/null
+++ b/guides/bug_report_templates/active_record_migrations_gem.rb
@@ -0,0 +1,68 @@
+# frozen_string_literal: true
+
+begin
+  require "bundler/inline"
+rescue LoadError => e
+  $stderr.puts "Bundler version 1.10 or later is required. Please update your Bundler"
+  raise e
+end
+
+gemfile(true) do
+  source "https://rubygems.org"
+
+  git_source(:github) { |repo| "https://github.com/#{repo}.git" }
+
+  # Activate the gem you are reporting the issue against.
+  gem "activerecord", "5.1.0"
+  gem "sqlite3"
+end
+
+require "active_record"
+require "minitest/autorun"
+require "logger"
+
+# Ensure backward compatibility with Minitest 4
+Minitest::Test = MiniTest::Unit::TestCase unless defined?(Minitest::Test)
+
+# This connection will do for database-independent bug reports.
+ActiveRecord::Base.establish_connection(adapter: "sqlite3", database: ":memory:")
+ActiveRecord::Base.logger = Logger.new(STDOUT)
+
+ActiveRecord::Schema.define do
+  create_table :payments, force: true do |t|
+    t.decimal :amount, precision: 10, scale: 0, default: 0, null: false
+  end
+end
+
+class Payment < ActiveRecord::Base
+end
+
+class ChangeAmountToAddScale < ActiveRecord::Migration[5.1]
+  def change
+    reversible do |dir|
+      dir.up do
+        change_column :payments, :amount, :decimal, precision: 10, scale: 2, default: 0, null: false
+      end
+
+      dir.down do
+        change_column :payments, :amount, :decimal, precision: 10, scale: 0, default: 0, null: false
+      end
+    end
+  end
+end
+
+class BugTest < Minitest::Test
+  def test_migration_up
+    ChangeAmountToAddScale.migrate(:up)
+    Payment.reset_column_information
+
+    assert_equal "decimal(10,2)", Payment.columns.last.sql_type
+  end
+
+  def test_migration_down
+    ChangeAmountToAddScale.migrate(:down)
+    Payment.reset_column_information
+
+    assert_equal "decimal(10,0)", Payment.columns.last.sql_type
+  end
+end
diff --git a/guides/bug_report_templates/active_record_migrations_master.rb b/guides/bug_report_templates/active_record_migrations_master.rb
new file mode 100644
index 0000000000..194b093ac3
--- /dev/null
+++ b/guides/bug_report_templates/active_record_migrations_master.rb
@@ -0,0 +1,67 @@
+# frozen_string_literal: true
+
+begin
+  require "bundler/inline"
+rescue LoadError => e
+  $stderr.puts "Bundler version 1.10 or later is required. Please update your Bundler"
+  raise e
+end
+
+gemfile(true) do
+  source "https://rubygems.org"
+
+  git_source(:github) { |repo| "https://github.com/#{repo}.git" }
+
+  gem "rails", github: "rails/rails"
+  gem "sqlite3"
+end
+
+require "active_record"
+require "minitest/autorun"
+require "logger"
+
+# Ensure backward compatibility with Minitest 4
+Minitest::Test = MiniTest::Unit::TestCase unless defined?(Minitest::Test)
+
+# This connection will do for database-independent bug reports.
+ActiveRecord::Base.establish_connection(adapter: "sqlite3", database: ":memory:")
+ActiveRecord::Base.logger = Logger.new(STDOUT)
+
+ActiveRecord::Schema.define do
+  create_table :payments, force: true do |t|
+    t.decimal :amount, precision: 10, scale: 0, default: 0, null: false
+  end
+end
+
+class Payment < ActiveRecord::Base
+end
+
+class ChangeAmountToAddScale < ActiveRecord::Migration[5.2]
+  def change
+    reversible do |dir|
+      dir.up do
+        change_column :payments, :amount, :decimal, precision: 10, scale: 2, default: 0, null: false
+      end
+
+      dir.down do
+        change_column :payments, :amount, :decimal, precision: 10, scale: 0, default: 0, null: false
+      end
+    end
+  end
+end
+
+class BugTest < Minitest::Test
+  def test_migration_up
+    ChangeAmountToAddScale.migrate(:up)
+    Payment.reset_column_information
+
+    assert_equal "decimal(10,2)", Payment.columns.last.sql_type
+  end
+
+  def test_migration_down
+    ChangeAmountToAddScale.migrate(:down)
+    Payment.reset_column_information
+
+    assert_equal "decimal(10,0)", Payment.columns.last.sql_type
+  end
+end
diff --git a/guides/bug_report_templates/benchmark.rb b/guides/bug_report_templates/benchmark.rb
new file mode 100644
index 0000000000..046572148b
--- /dev/null
+++ b/guides/bug_report_templates/benchmark.rb
@@ -0,0 +1,54 @@
+# frozen_string_literal: true
+
+begin
+  require "bundler/inline"
+rescue LoadError => e
+  $stderr.puts "Bundler version 1.10 or later is required. Please update your Bundler"
+  raise e
+end
+
+gemfile(true) do
+  source "https://rubygems.org"
+
+  git_source(:github) { |repo| "https://github.com/#{repo}.git" }
+
+  gem "rails", github: "rails/rails"
+  gem "benchmark-ips"
+end
+
+require "active_support"
+require "active_support/core_ext/object/blank"
+
+# Your patch goes here.
+class String
+  def fast_blank?
+    true
+  end
+end
+
+# Enumerate some representative scenarios here.
+#
+# It is very easy to make an optimization that improves performance for a
+# specific scenario you care about but regresses on other common cases.
+# Therefore, you should test your change against a list of representative
+# scenarios. Ideally, they should be based on real-world scenarios extracted
+# from production applications.
+SCENARIOS = {
+  "Empty"            => "",
+  "Single Space"     => " ",
+  "Two Spaces"       => "  ",
+  "Mixed Whitspaces" => " \t\r\n",
+  "Very Long String" => " " * 100
+}
+
+SCENARIOS.each_pair do |name, value|
+  puts
+  puts " #{name} ".center(80, "=")
+  puts
+
+  Benchmark.ips do |x|
+    x.report("blank?")      { value.blank? }
+    x.report("fast_blank?") { value.fast_blank? }
+    x.compare!
+  end
+end
diff --git a/guides/bug_report_templates/generic_gem.rb b/guides/bug_report_templates/generic_gem.rb
index bb8af3be18..60e8322c2a 100644
--- a/guides/bug_report_templates/generic_gem.rb
+++ b/guides/bug_report_templates/generic_gem.rb
@@ -1,18 +1,23 @@
+# frozen_string_literal: true
+
 begin
-  require 'bundler/inline'
+  require "bundler/inline"
 rescue LoadError => e
-  $stderr.puts 'Bundler version 1.10 or later is required. Please update your Bundler'
+  $stderr.puts "Bundler version 1.10 or later is required. Please update your Bundler"
   raise e
 end
 
 gemfile(true) do
-  source 'https://rubygems.org'
+  source "https://rubygems.org"
+
+  git_source(:github) { |repo| "https://github.com/#{repo}.git" }
+
   # Activate the gem you are reporting the issue against.
-  gem 'activesupport', '5.0.0.rc1'
+  gem "activesupport", "5.1.0"
 end
 
-require 'active_support/core_ext/object/blank'
-require 'minitest/autorun'
+require "active_support/core_ext/object/blank"
+require "minitest/autorun"
 
 # Ensure backward compatibility with Minitest 4
 Minitest::Test = MiniTest::Unit::TestCase unless defined?(Minitest::Test)
diff --git a/guides/bug_report_templates/generic_master.rb b/guides/bug_report_templates/generic_master.rb
index 70cf931f34..727f428960 100644
--- a/guides/bug_report_templates/generic_master.rb
+++ b/guides/bug_report_templates/generic_master.rb
@@ -1,18 +1,23 @@
+# frozen_string_literal: true
+
 begin
-  require 'bundler/inline'
+  require "bundler/inline"
 rescue LoadError => e
-  $stderr.puts 'Bundler version 1.10 or later is required. Please update your Bundler'
+  $stderr.puts "Bundler version 1.10 or later is required. Please update your Bundler"
   raise e
 end
 
 gemfile(true) do
-  source 'https://rubygems.org'
-  gem 'rails', github: 'rails/rails'
+  source "https://rubygems.org"
+
+  git_source(:github) { |repo| "https://github.com/#{repo}.git" }
+
+  gem "rails", github: "rails/rails"
 end
 
-require 'active_support'
-require 'active_support/core_ext/object/blank'
-require 'minitest/autorun'
+require "active_support"
+require "active_support/core_ext/object/blank"
+require "minitest/autorun"
 
 class BugTest < Minitest::Test
   def test_stuff
diff --git a/guides/rails_guides.rb b/guides/rails_guides.rb
index 367ed0b12e..f2d4d6f647 100644
--- a/guides/rails_guides.rb
+++ b/guides/rails_guides.rb
@@ -1,17 +1,29 @@
-pwd = File.dirname(__FILE__)
-$:.unshift pwd
+# frozen_string_literal: true
 
-begin
-  # Guides generation in the Rails repo.
-  as_lib = File.join(pwd, "../activesupport/lib")
-  ap_lib = File.join(pwd, "../actionpack/lib")
+$:.unshift __dir__
 
-  $:.unshift as_lib if File.directory?(as_lib)
-  $:.unshift ap_lib if File.directory?(ap_lib)
-rescue LoadError
-  # Guides generation from gems.
-  gem "actionpack", '>= 3.0'
-end
+as_lib = File.expand_path("../activesupport/lib", __dir__)
+ap_lib = File.expand_path("../actionpack/lib", __dir__)
+av_lib = File.expand_path("../actionview/lib", __dir__)
+
+$:.unshift as_lib if File.directory?(as_lib)
+$:.unshift ap_lib if File.directory?(ap_lib)
+$:.unshift av_lib if File.directory?(av_lib)
 
 require "rails_guides/generator"
-RailsGuides::Generator.new.generate
+require "active_support/core_ext/object/blank"
+
+env_value = ->(name) { ENV[name].presence }
+env_flag  = ->(name) { "1" == env_value[name] }
+
+version = env_value["RAILS_VERSION"]
+edge    = `git rev-parse HEAD`.strip unless version
+
+RailsGuides::Generator.new(
+  edge:     edge,
+  version:  version,
+  all:      env_flag["ALL"],
+  only:     env_value["ONLY"],
+  kindle:   env_flag["KINDLE"],
+  language: env_value["GUIDES_LANGUAGE"]
+).generate
diff --git a/guides/rails_guides/generator.rb b/guides/rails_guides/generator.rb
index 7618fce2c8..7205f37be7 100644
--- a/guides/rails_guides/generator.rb
+++ b/guides/rails_guides/generator.rb
@@ -1,249 +1,208 @@
-# ---------------------------------------------------------------------------
-#
-# This script generates the guides. It can be invoked via the
-# guides:generate rake task within the guides directory.
-#
-# Guides are taken from the source directory, and the resulting HTML goes into the
-# output directory. Assets are stored under files, and copied to output/files as
-# part of the generation process.
-#
-# Some arguments may be passed via environment variables:
-#
-#   WARNINGS
-#     If you are writing a guide, please work always with WARNINGS=1. Users can
-#     generate the guides, and thus this flag is off by default.
-#
-#     Internal links (anchors) are checked. If a reference is broken levenshtein
-#     distance is used to suggest an existing one. This is useful since IDs are
-#     generated by Markdown from headers and thus edits alter them.
-#
-#     Also detects duplicated IDs. They happen if there are headers with the same
-#     text. Please do resolve them, if any, so guides are valid XHTML.
-#
-#   ALL
-#    Set to "1" to force the generation of all guides.
-#
-#   ONLY
-#     Use ONLY if you want to generate only one or a set of guides. Prefixes are
-#     enough:
-#
-#       # generates only association_basics.html
-#       ONLY=assoc ruby rails_guides.rb
-#
-#     Separate many using commas:
-#
-#       # generates only association_basics.html and migrations.html
-#       ONLY=assoc,migrations ruby rails_guides.rb
-#
-#     Note that if you are working on a guide generation will by default process
-#     only that one, so ONLY is rarely used nowadays.
-#
-#   GUIDES_LANGUAGE
-#     Use GUIDES_LANGUAGE when you want to generate translated guides in
-#     <tt>source/<GUIDES_LANGUAGE></tt> folder (such as <tt>source/es</tt>).
-#     Ignore it when generating English guides.
-#
-#   EDGE
-#     Set to "1" to indicate generated guides should be marked as edge. This
-#     inserts a badge and changes the preamble of the home page.
-#
-# ---------------------------------------------------------------------------
-
-require 'set'
-require 'fileutils'
-
-require 'active_support/core_ext/string/output_safety'
-require 'active_support/core_ext/object/blank'
-require 'action_controller'
-require 'action_view'
-
-require 'rails_guides/markdown'
-require 'rails_guides/indexer'
-require 'rails_guides/helpers'
-require 'rails_guides/levenshtein'
+# frozen_string_literal: true
+
+require "set"
+require "fileutils"
+
+require "active_support/core_ext/string/output_safety"
+require "active_support/core_ext/object/blank"
+require "action_controller"
+require "action_view"
+
+require "rails_guides/markdown"
+require "rails_guides/indexer"
+require "rails_guides/helpers"
+require "rails_guides/levenshtein"
 
 module RailsGuides
   class Generator
-    attr_reader :guides_dir, :source_dir, :output_dir, :edge, :warnings, :all
-
     GUIDES_RE = /\.(?:erb|md)\z/
 
-    def initialize(output=nil)
-      set_flags_from_environment
+    def initialize(edge:, version:, all:, only:, kindle:, language:)
+      @edge     = edge
+      @version  = version
+      @all      = all
+      @only     = only
+      @kindle   = kindle
+      @language = language
 
-      if kindle?
+      if @kindle
         check_for_kindlegen
         register_kindle_mime_types
       end
 
-      initialize_dirs(output)
+      initialize_dirs
       create_output_dir_if_needed
-    end
-
-    def set_flags_from_environment
-      @edge     = ENV['EDGE']     == '1'
-      @warnings = ENV['WARNINGS'] == '1'
-      @all      = ENV['ALL']      == '1'
-      @kindle   = ENV['KINDLE']   == '1'
-      @version  = ENV['RAILS_VERSION'] || 'local'
-      @lang     = ENV['GUIDES_LANGUAGE']
-    end
-
-    def register_kindle_mime_types
-      Mime::Type.register_alias("application/xml", :opf, %w(opf))
-      Mime::Type.register_alias("application/xml", :ncx, %w(ncx))
+      initialize_markdown_renderer
     end
 
     def generate
       generate_guides
       copy_assets
-      generate_mobi if kindle?
+      generate_mobi if @kindle
     end
 
     private
 
-    def kindle?
-      @kindle
-    end
+      def register_kindle_mime_types
+        Mime::Type.register_alias("application/xml", :opf, %w(opf))
+        Mime::Type.register_alias("application/xml", :ncx, %w(ncx))
+      end
 
-    def check_for_kindlegen
-      if `which kindlegen`.blank?
-        raise "Can't create a kindle version without `kindlegen`."
+      def check_for_kindlegen
+        if `which kindlegen`.blank?
+          raise "Can't create a kindle version without `kindlegen`."
+        end
       end
-    end
 
-    def generate_mobi
-      require 'rails_guides/kindle'
-      out = "#{output_dir}/kindlegen.out"
-      Kindle.generate(output_dir, mobi, out)
-      puts "(kindlegen log at #{out})."
-    end
+      def generate_mobi
+        require "rails_guides/kindle"
+        out = "#{@output_dir}/kindlegen.out"
+        Kindle.generate(@output_dir, mobi, out)
+        puts "(kindlegen log at #{out})."
+      end
 
-    def mobi
-      "ruby_on_rails_guides_#@version%s.mobi" % (@lang.present? ? ".#@lang" : '')
-    end
+      def mobi
+        mobi  = "ruby_on_rails_guides_#{@version || @edge[0, 7]}"
+        mobi += ".#{@language}" if @language
+        mobi += ".mobi"
+      end
 
-    def initialize_dirs(output)
-      @guides_dir = File.join(File.dirname(__FILE__), '..')
-      @source_dir = "#@guides_dir/source/#@lang"
-      @output_dir = if output
-        output
-      elsif kindle?
-        "#@guides_dir/output/kindle/#@lang"
-      else
-        "#@guides_dir/output/#@lang"
-      end.sub(%r</$>, '')
-    end
+      def initialize_dirs
+        @guides_dir = File.expand_path("..", __dir__)
 
-    def create_output_dir_if_needed
-      FileUtils.mkdir_p(output_dir)
-    end
+        @source_dir  = "#{@guides_dir}/source"
+        @source_dir += "/#{@language}" if @language
 
-    def generate_guides
-      guides_to_generate.each do |guide|
-        output_file = output_file_for(guide)
-        generate_guide(guide, output_file) if generate?(guide, output_file)
+        @output_dir  = "#{@guides_dir}/output"
+        @output_dir += "/kindle"       if @kindle
+        @output_dir += "/#{@language}" if @language
       end
-    end
 
-    def guides_to_generate
-      guides = Dir.entries(source_dir).grep(GUIDES_RE)
-
-      if kindle?
-        Dir.entries("#{source_dir}/kindle").grep(GUIDES_RE).map do |entry|
-          next if entry == 'KINDLE.md'
-          guides << "kindle/#{entry}"
-        end
+      def create_output_dir_if_needed
+        FileUtils.mkdir_p(@output_dir)
       end
 
-      ENV.key?('ONLY') ? select_only(guides) : guides
-    end
-
-    def select_only(guides)
-      prefixes = ENV['ONLY'].split(",").map(&:strip)
-      guides.select do |guide|
-        guide.start_with?('kindle'.freeze, *prefixes)
+      def initialize_markdown_renderer
+        Markdown::Renderer.edge    = @edge
+        Markdown::Renderer.version = @version
       end
-    end
 
-    def copy_assets
-      FileUtils.cp_r(Dir.glob("#{guides_dir}/assets/*"), output_dir)
-    end
-
-    def output_file_for(guide)
-      if guide.end_with?('.md')
-        guide.sub(/md\z/, 'html')
-      else
-        guide.sub(/\.erb\z/, '')
+      def generate_guides
+        guides_to_generate.each do |guide|
+          output_file = output_file_for(guide)
+          generate_guide(guide, output_file) if generate?(guide, output_file)
+        end
       end
-    end
 
-    def output_path_for(output_file)
-      File.join(output_dir, File.basename(output_file))
-    end
+      def guides_to_generate
+        guides = Dir.entries(@source_dir).grep(GUIDES_RE)
 
-    def generate?(source_file, output_file)
-      fin  = File.join(source_dir, source_file)
-      fout = output_path_for(output_file)
-      all || !File.exist?(fout) || File.mtime(fout) < File.mtime(fin)
-    end
+        if @kindle
+          Dir.entries("#{@source_dir}/kindle").grep(GUIDES_RE).map do |entry|
+            next if entry == "KINDLE.md"
+            guides << "kindle/#{entry}"
+          end
+        end
 
-    def generate_guide(guide, output_file)
-      output_path = output_path_for(output_file)
-      puts "Generating #{guide} as #{output_file}"
-      layout = kindle? ? 'kindle/layout' : 'layout'
+        @only ? select_only(guides) : guides
+      end
+
+      def select_only(guides)
+        prefixes = @only.split(",").map(&:strip)
+        guides.select do |guide|
+          guide.start_with?("kindle", *prefixes)
+        end
+      end
 
-      File.open(output_path, 'w') do |f|
-        view = ActionView::Base.new(source_dir, :edge => @edge, :version => @version, :mobi => "kindle/#{mobi}", :lang => @lang)
-        view.extend(Helpers)
+      def copy_assets
+        FileUtils.cp_r(Dir.glob("#{@guides_dir}/assets/*"), @output_dir)
+      end
 
-        if guide =~ /\.(\w+)\.erb$/
-          # Generate the special pages like the home.
-          # Passing a template handler in the template name is deprecated. So pass the file name without the extension.
-          result = view.render(:layout => layout, :formats => [$1], :file => $`)
+      def output_file_for(guide)
+        if guide.end_with?(".md")
+          guide.sub(/md\z/, "html")
         else
-          body = File.read(File.join(source_dir, guide))
-          result = RailsGuides::Markdown.new(view, layout).render(body)
-
-          warn_about_broken_links(result) if @warnings
+          guide.sub(/\.erb\z/, "")
         end
+      end
 
-        f.write(result)
+      def output_path_for(output_file)
+        File.join(@output_dir, File.basename(output_file))
       end
-    end
 
-    def warn_about_broken_links(html)
-      anchors = extract_anchors(html)
-      check_fragment_identifiers(html, anchors)
-    end
+      def generate?(source_file, output_file)
+        fin  = File.join(@source_dir, source_file)
+        fout = output_path_for(output_file)
+        @all || !File.exist?(fout) || File.mtime(fout) < File.mtime(fin)
+      end
 
-    def extract_anchors(html)
-      # Markdown generates headers with IDs computed from titles.
-      anchors = Set.new
-      html.scan(/<h\d\s+id="([^"]+)/).flatten.each do |anchor|
-        if anchors.member?(anchor)
-          puts "*** DUPLICATE ID: #{anchor}, please make sure that there're no headings with the same name at the same level."
-        else
-          anchors << anchor
+      def generate_guide(guide, output_file)
+        output_path = output_path_for(output_file)
+        puts "Generating #{guide} as #{output_file}"
+        layout = @kindle ? "kindle/layout" : "layout"
+
+        File.open(output_path, "w") do |f|
+          view = ActionView::Base.new(
+            @source_dir,
+            edge:     @edge,
+            version:  @version,
+            mobi:     "kindle/#{mobi}",
+            language: @language
+          )
+          view.extend(Helpers)
+
+          if guide =~ /\.(\w+)\.erb$/
+            # Generate the special pages like the home.
+            # Passing a template handler in the template name is deprecated. So pass the file name without the extension.
+            result = view.render(layout: layout, formats: [$1], file: $`)
+          else
+            body = File.read("#{@source_dir}/#{guide}")
+            result = RailsGuides::Markdown.new(
+              view:    view,
+              layout:  layout,
+              edge:    @edge,
+              version: @version
+            ).render(body)
+
+            warn_about_broken_links(result)
+          end
+
+          f.write(result)
         end
       end
 
-      # Footnotes.
-      anchors += Set.new(html.scan(/<p\s+class="footnote"\s+id="([^"]+)/).flatten)
-      anchors += Set.new(html.scan(/<sup\s+class="footnote"\s+id="([^"]+)/).flatten)
-      return anchors
-    end
+      def warn_about_broken_links(html)
+        anchors = extract_anchors(html)
+        check_fragment_identifiers(html, anchors)
+      end
 
-    def check_fragment_identifiers(html, anchors)
-      html.scan(/<a\s+href="#([^"]+)/).flatten.each do |fragment_identifier|
-        next if fragment_identifier == 'mainCol' # in layout, jumps to some DIV
-        unless anchors.member?(fragment_identifier)
-          guess = anchors.min { |a, b|
-            Levenshtein.distance(fragment_identifier, a) <=> Levenshtein.distance(fragment_identifier, b)
-          }
-          puts "*** BROKEN LINK: ##{fragment_identifier}, perhaps you meant ##{guess}."
+      def extract_anchors(html)
+        # Markdown generates headers with IDs computed from titles.
+        anchors = Set.new
+        html.scan(/<h\d\s+id="([^"]+)/).flatten.each do |anchor|
+          if anchors.member?(anchor)
+            puts "*** DUPLICATE ID: #{anchor}, please make sure that there're no headings with the same name at the same level."
+          else
+            anchors << anchor
+          end
+        end
+
+        # Footnotes.
+        anchors += Set.new(html.scan(/<p\s+class="footnote"\s+id="([^"]+)/).flatten)
+        anchors += Set.new(html.scan(/<sup\s+class="footnote"\s+id="([^"]+)/).flatten)
+        anchors
+      end
+
+      def check_fragment_identifiers(html, anchors)
+        html.scan(/<a\s+href="#([^"]+)/).flatten.each do |fragment_identifier|
+          next if fragment_identifier == "mainCol" # in layout, jumps to some DIV
+          unless anchors.member?(fragment_identifier)
+            guess = anchors.min { |a, b|
+              Levenshtein.distance(fragment_identifier, a) <=> Levenshtein.distance(fragment_identifier, b)
+            }
+            puts "*** BROKEN LINK: ##{fragment_identifier}, perhaps you meant ##{guess}."
+          end
         end
       end
-    end
   end
 end
diff --git a/guides/rails_guides/helpers.rb b/guides/rails_guides/helpers.rb
index 5bf73da16c..a6970fb90c 100644
--- a/guides/rails_guides/helpers.rb
+++ b/guides/rails_guides/helpers.rb
@@ -1,13 +1,15 @@
-require 'yaml'
+# frozen_string_literal: true
+
+require "yaml"
 
 module RailsGuides
   module Helpers
     def guide(name, url, options = {}, &block)
-      link = content_tag(:a, :href => url) { name }
+      link = content_tag(:a, href: url) { name }
       result = content_tag(:dt, link)
 
       if options[:work_in_progress]
-        result << content_tag(:dd, 'Work in progress', :class => 'work-in-progress')
+        result << content_tag(:dd, "Work in progress", class: "work-in-progress")
       end
 
       result << content_tag(:dd, capture(&block))
@@ -15,34 +17,34 @@ module RailsGuides
     end
 
     def documents_by_section
-      @documents_by_section ||= YAML.load_file(File.expand_path("../../source/#{@lang ? @lang + '/' : ''}documents.yaml", __FILE__))
+      @documents_by_section ||= YAML.load_file(File.expand_path("../source/#{@language ? @language + '/' : ''}documents.yaml", __dir__))
     end
 
     def documents_flat
-      documents_by_section.flat_map {|section| section['documents']}
+      documents_by_section.flat_map { |section| section["documents"] }
     end
 
     def finished_documents(documents)
-      documents.reject { |document| document['work_in_progress'] }
+      documents.reject { |document| document["work_in_progress"] }
     end
 
-    def docs_for_menu(position=nil)
+    def docs_for_menu(position = nil)
       if position.nil?
         documents_by_section
-      elsif position == 'L'
+      elsif position == "L"
         documents_by_section.to(3)
       else
         documents_by_section.from(4)
       end
     end
 
-    def author(name, nick, image = 'credits_pic_blank.gif', &block)
+    def author(name, nick, image = "credits_pic_blank.gif", &block)
       image = "images/#{image}"
 
-      result = tag(:img, :src => image, :class => 'left pic', :alt => name, :width => 91, :height => 91)
+      result = tag(:img, src: image, class: "left pic", alt: name, width: 91, height: 91)
       result << content_tag(:h3, name)
       result << content_tag(:p, capture(&block))
-      content_tag(:div, result, :class => 'clearfix', :id => nick)
+      content_tag(:div, result, class: "clearfix", id: nick)
     end
 
     def code(&block)
diff --git a/guides/rails_guides/indexer.rb b/guides/rails_guides/indexer.rb
index 89fbccbb1d..c707464cdf 100644
--- a/guides/rails_guides/indexer.rb
+++ b/guides/rails_guides/indexer.rb
@@ -1,5 +1,7 @@
-require 'active_support/core_ext/object/blank'
-require 'active_support/core_ext/string/inflections'
+# frozen_string_literal: true
+
+require "active_support/core_ext/object/blank"
+require "active_support/core_ext/string/inflections"
 
 module RailsGuides
   class Indexer
@@ -17,52 +19,52 @@ module RailsGuides
 
     private
 
-    def process(string, current_level=3, counters=[1])
-      s = StringScanner.new(string)
+      def process(string, current_level = 3, counters = [1])
+        s = StringScanner.new(string)
 
-      level_hash = {}
+        level_hash = {}
 
-      while !s.eos?
-        re = %r{^h(\d)(?:\((#.*?)\))?\s*\.\s*(.*)$}
-        s.match?(re)
-        if matched = s.matched
-          matched =~ re
-          level, idx, title = $1.to_i, $2, $3.strip
+        while !s.eos?
+          re = %r{^h(\d)(?:\((#.*?)\))?\s*\.\s*(.*)$}
+          s.match?(re)
+          if matched = s.matched
+            matched =~ re
+            level, idx, title = $1.to_i, $2, $3.strip
 
-          if level < current_level
-            # This is needed. Go figure.
-            return level_hash
-          elsif level == current_level
-            index = counters.join(".")
-            idx ||= '#' + title_to_idx(title)
+            if level < current_level
+              # This is needed. Go figure.
+              return level_hash
+            elsif level == current_level
+              index = counters.join(".")
+              idx ||= "#" + title_to_idx(title)
 
-            raise "Parsing Fail" unless @result.sub!(matched, "h#{level}(#{idx}). #{index} #{title}")
+              raise "Parsing Fail" unless @result.sub!(matched, "h#{level}(#{idx}). #{index} #{title}")
 
-            key = {
-              :title => title,
-              :id => idx
-            }
-            # Recurse
-            counters << 1
-            level_hash[key] = process(s.post_match, current_level + 1, counters)
-            counters.pop
+              key = {
+                title: title,
+                id: idx
+              }
+              # Recurse
+              counters << 1
+              level_hash[key] = process(s.post_match, current_level + 1, counters)
+              counters.pop
 
-            # Increment the current level
-            last = counters.pop
-            counters << last + 1
+              # Increment the current level
+              last = counters.pop
+              counters << last + 1
+            end
           end
+          s.getch
         end
-        s.getch
+        level_hash
       end
-      level_hash
-    end
 
-    def title_to_idx(title)
-      idx = title.strip.parameterize.sub(/^\d+/, '')
-      if warnings && idx.blank?
-        puts "BLANK ID: please put an explicit ID for section #{title}, as in h5(#my-id)"
+      def title_to_idx(title)
+        idx = title.strip.parameterize.sub(/^\d+/, "")
+        if warnings && idx.blank?
+          puts "BLANK ID: please put an explicit ID for section #{title}, as in h5(#my-id)"
+        end
+        idx
       end
-      idx
-    end
   end
 end
diff --git a/guides/rails_guides/kindle.rb b/guides/rails_guides/kindle.rb
index 081afcb09f..87a369a15a 100644
--- a/guides/rails_guides/kindle.rb
+++ b/guides/rails_guides/kindle.rb
@@ -1,26 +1,24 @@
 #!/usr/bin/env ruby
+# frozen_string_literal: true
 
-unless `which kindlerb` 
-  abort "Please gem install kindlerb"
-end
-
-require 'nokogiri'
-require 'fileutils'
-require 'yaml'
-require 'date'
+require "kindlerb"
+require "nokogiri"
+require "fileutils"
+require "yaml"
+require "date"
 
 module Kindle
   extend self
 
   def generate(output_dir, mobi_outfile, logfile)
     output_dir = File.absolute_path(output_dir)
-    Dir.chdir output_dir do 
+    Dir.chdir output_dir do
       puts "=> Using output dir: #{output_dir}"
       puts "=> Arranging html pages in document order"
       toc = File.read("toc.ncx")
-      doc = Nokogiri::XML(toc).xpath("//ncx:content", 'ncx' => "http://www.daisy.org/z3986/2005/ncx/")
-      html_pages = doc.select {|c| c[:src]}.map {|c| c[:src]}.uniq
-     
+      doc = Nokogiri::XML(toc).xpath("//ncx:content", "ncx" => "http://www.daisy.org/z3986/2005/ncx/")
+      html_pages = doc.select { |c| c[:src] }.map { |c| c[:src] }.uniq
+
       generate_front_matter(html_pages)
 
       generate_sections(html_pages)
@@ -28,35 +26,34 @@ module Kindle
       generate_document_metadata(mobi_outfile)
 
       puts "Creating MOBI document with kindlegen. This may take a while."
-      cmd = "kindlerb . > #{File.absolute_path logfile} 2>&1"
-      puts cmd
-      system(cmd)
-      puts "MOBI document generated at #{File.expand_path(mobi_outfile, output_dir)}"
+      if Kindlerb.run(output_dir)
+        puts "MOBI document generated at #{File.expand_path(mobi_outfile, output_dir)}"
+      end
     end
   end
 
   def generate_front_matter(html_pages)
     frontmatter = []
-    html_pages.delete_if {|x| 
+    html_pages.delete_if { |x|
       if x =~ /(toc|welcome|credits|copyright).html/
         frontmatter << x unless x =~ /toc/
         true
       end
     }
-    html = frontmatter.map {|x|
+    html = frontmatter.map { |x|
       Nokogiri::HTML(File.open(x)).at("body").inner_html
     }.join("\n")
 
     fdoc = Nokogiri::HTML(html)
     fdoc.search("h3").each do |h3|
-      h3.name = 'h4'
+      h3.name = "h4"
     end
-    fdoc.search("h2").each do |h2| 
-      h2.name = 'h3'
-      h2['id'] = h2.inner_text.gsub(/\s/, '-')
+    fdoc.search("h2").each do |h2|
+      h2.name = "h3"
+      h2["id"] = h2.inner_text.gsub(/\s/, "-")
     end
     add_head_section fdoc, "Front Matter"
-    File.open("frontmatter.html",'w') {|f| f.puts fdoc.to_html}
+    File.open("frontmatter.html", "w") { |f| f.puts fdoc.to_html }
     html_pages.unshift "frontmatter.html"
   end
 
@@ -65,20 +62,20 @@ module Kindle
     html_pages.each_with_index do |page, section_idx|
       FileUtils::mkdir_p("sections/%03d" % section_idx)
       doc = Nokogiri::HTML(File.open(page))
-      title = doc.at("title").inner_text.gsub("Ruby on Rails Guides: ", '')
-      title = page.capitalize.gsub('.html', '') if title.strip == ''
-      File.open("sections/%03d/_section.txt" % section_idx, 'w') {|f| f.puts title}
-      doc.xpath("//h3[@id]").each_with_index do |h3,item_idx|
+      title = doc.at("title").inner_text.gsub("Ruby on Rails Guides: ", "")
+      title = page.capitalize.gsub(".html", "") if title.strip == ""
+      File.open("sections/%03d/_section.txt" % section_idx, "w") { |f| f.puts title }
+      doc.xpath("//h3[@id]").each_with_index do |h3, item_idx|
         subsection = h3.inner_text
-        content = h3.xpath("./following-sibling::*").take_while {|x| x.name != "h3"}.map(&:to_html)
+        content = h3.xpath("./following-sibling::*").take_while { |x| x.name != "h3" }.map(&:to_html)
         item = Nokogiri::HTML(h3.to_html + content.join("\n"))
-        item_path = "sections/%03d/%03d.html" % [section_idx, item_idx] 
+        item_path = "sections/%03d/%03d.html" % [section_idx, item_idx]
         add_head_section(item, subsection)
         item.search("img").each do |img|
-          img['src'] = "#{Dir.pwd}/#{img['src']}"
+          img["src"] = "#{Dir.pwd}/#{img['src']}"
         end
-        item.xpath("//li/p").each {|p| p.swap(p.children); p.remove}
-        File.open(item_path, 'w') {|f| f.puts item.to_html}
+        item.xpath("//li/p").each { |p| p.swap(p.children); p.remove }
+        File.open(item_path, "w") { |f| f.puts item.to_html }
       end
     end
   end
@@ -87,21 +84,21 @@ module Kindle
     puts "=> Generating _document.yml"
     x = Nokogiri::XML(File.open("rails_guides.opf")).remove_namespaces!
     cover_jpg = "#{Dir.pwd}/images/rails_guides_kindle_cover.jpg"
-    cover_gif = cover_jpg.sub(/jpg$/, 'gif')
+    cover_gif = cover_jpg.sub(/jpg$/, "gif")
     puts `convert #{cover_jpg} #{cover_gif}`
     document = {
-      'doc_uuid' => x.at("package")['unique-identifier'],
-      'title' => x.at("title").inner_text.gsub(/\(.*$/, " v2"),
-      'publisher' => x.at("publisher").inner_text,
-      'author' => x.at("creator").inner_text,
-      'subject' => x.at("subject").inner_text,
-      'date' => x.at("date").inner_text,
-      'cover' => cover_gif,
-      'masthead' => nil,
-      'mobi_outfile' => mobi_outfile
+      "doc_uuid" => x.at("package")["unique-identifier"],
+      "title" => x.at("title").inner_text.gsub(/\(.*$/, " v2"),
+      "publisher" => x.at("publisher").inner_text,
+      "author" => x.at("creator").inner_text,
+      "subject" => x.at("subject").inner_text,
+      "date" => x.at("date").inner_text,
+      "cover" => cover_gif,
+      "masthead" => nil,
+      "mobi_outfile" => mobi_outfile
     }
     puts document.to_yaml
-    File.open("_document.yml", 'w'){|f| f.puts document.to_yaml}
+    File.open("_document.yml", "w") { |f| f.puts document.to_yaml }
   end
 
   def add_head_section(doc, title)
@@ -110,9 +107,9 @@ module Kindle
     title_node.content = title
     title_node.parent = head
     css = Nokogiri::XML::Node.new "link", doc
-    css['rel'] = 'stylesheet'
-    css['type'] = 'text/css'
-    css['href'] = "#{Dir.pwd}/stylesheets/kindle.css"
+    css["rel"] = "stylesheet"
+    css["type"] = "text/css"
+    css["href"] = "#{Dir.pwd}/stylesheets/kindle.css"
     css.parent = head
     doc.at("body").before head
   end
diff --git a/guides/rails_guides/levenshtein.rb b/guides/rails_guides/levenshtein.rb
index 049f633258..c48af797fa 100644
--- a/guides/rails_guides/levenshtein.rb
+++ b/guides/rails_guides/levenshtein.rb
@@ -1,8 +1,12 @@
+# frozen_string_literal: true
+
 module RailsGuides
   module Levenshtein
-    # This code is based directly on the Text gem implementation
+    # This code is based directly on the Text gem implementation.
+    # Copyright (c) 2006-2013 Paul Battley, Michael Neumann, Tim Fletcher.
+    #
     # Returns a value representing the "cost" of transforming str1 into str2
-    def self.distance str1, str2
+    def self.distance(str1, str2)
       s = str1
       t = str2
       n = s.length
@@ -18,12 +22,12 @@ module RailsGuides
       str2_codepoint_enumerable = str2.each_codepoint
 
       str1.each_codepoint.with_index do |char1, i|
-        e = i+1
+        e = i + 1
 
         str2_codepoint_enumerable.with_index do |char2, j|
           cost = (char1 == char2) ? 0 : 1
           x = [
-               d[j+1] + 1, # insertion
+               d[j + 1] + 1, # insertion
                e + 1,      # deletion
                d[j] + cost # substitution
               ].min
@@ -34,7 +38,7 @@ module RailsGuides
         d[m] = x
       end
 
-      return x
+      x
     end
   end
 end
diff --git a/guides/rails_guides/markdown.rb b/guides/rails_guides/markdown.rb
index 69c7cd5136..84f95eec68 100644
--- a/guides/rails_guides/markdown.rb
+++ b/guides/rails_guides/markdown.rb
@@ -1,15 +1,19 @@
-require 'redcarpet'
-require 'nokogiri'
-require 'rails_guides/markdown/renderer'
+# frozen_string_literal: true
+
+require "redcarpet"
+require "nokogiri"
+require "rails_guides/markdown/renderer"
 
 module RailsGuides
   class Markdown
-    def initialize(view, layout)
-      @view = view
-      @layout = layout
+    def initialize(view:, layout:, edge:, version:)
+      @view          = view
+      @layout        = layout
+      @edge          = edge
+      @version       = version
       @index_counter = Hash.new(0)
-      @raw_header = ''
-      @node_ids = {}
+      @raw_header    = ""
+      @node_ids      = {}
     end
 
     def render(body)
@@ -47,21 +51,21 @@ module RailsGuides
       def dom_id_text(text)
         escaped_chars = Regexp.escape('\\/`*_{}[]()#+-.!:,;|&<>^~=\'"')
 
-        text.downcase.gsub(/\?/, '-questionmark')
-                     .gsub(/!/, '-bang')
-                     .gsub(/[#{escaped_chars}]+/, ' ').strip
-                     .gsub(/\s+/, '-')
+        text.downcase.gsub(/\?/, "-questionmark")
+                     .gsub(/!/, "-bang")
+                     .gsub(/[#{escaped_chars}]+/, " ").strip
+                     .gsub(/\s+/, "-")
       end
 
       def engine
-        @engine ||= Redcarpet::Markdown.new(Renderer, {
+        @engine ||= Redcarpet::Markdown.new(Renderer,
           no_intra_emphasis: true,
           fenced_code_blocks: true,
           autolink: true,
           strikethrough: true,
           superscript: true,
           tables: true
-        })
+        )
       end
 
       def extract_raw_header_and_body
@@ -87,15 +91,15 @@ module RailsGuides
             doc.children.each do |node|
               if node.name =~ /^h[3-6]$/
                 case node.name
-                when 'h3'
+                when "h3"
                   hierarchy = [node]
                   @headings_for_index << [1, node, node.inner_html]
-                when 'h4'
+                when "h4"
                   hierarchy = hierarchy[0, 1] + [node]
                   @headings_for_index << [2, node, node.inner_html]
-                when 'h5'
+                when "h5"
                   hierarchy = hierarchy[0, 2] + [node]
-                when 'h6'
+                when "h6"
                   hierarchy = hierarchy[0, 3] + [node]
                 end
 
@@ -103,13 +107,17 @@ module RailsGuides
                 node.inner_html = "#{node_index(hierarchy)} #{node.inner_html}"
               end
             end
+
+            doc.css("h3, h4, h5, h6").each do |node|
+              node.inner_html = "<a class='anchorlink' href='##{node[:id]}'>#{node.inner_html}</a>"
+            end
           end.to_html
         end
       end
 
       def generate_index
         if @headings_for_index.present?
-          raw_index = ''
+          raw_index = ""
           @headings_for_index.each do |level, node, label|
             if level == 1
               raw_index += "1. [#{label}](##{node[:id]})\n"
@@ -119,7 +127,7 @@ module RailsGuides
           end
 
           @index = Nokogiri::HTML.fragment(engine.render(raw_index)).tap do |doc|
-            doc.at('ol')[:class] = 'chapters'
+            doc.at("ol")[:class] = "chapters"
           end.to_html
 
           @index = <<-INDEX.html_safe
@@ -159,7 +167,7 @@ module RailsGuides
         @view.content_for(:header_section) { @header }
         @view.content_for(:page_title) { @title }
         @view.content_for(:index_section) { @index }
-        @view.render(:layout => @layout, :text => @body)
+        @view.render(layout: @layout, html: @body.html_safe)
       end
   end
 end
diff --git a/guides/rails_guides/markdown/renderer.rb b/guides/rails_guides/markdown/renderer.rb
index 73ca600361..78820a7856 100644
--- a/guides/rails_guides/markdown/renderer.rb
+++ b/guides/rails_guides/markdown/renderer.rb
@@ -1,9 +1,9 @@
+# frozen_string_literal: true
+
 module RailsGuides
   class Markdown
     class Renderer < Redcarpet::Render::HTML
-      def initialize(options={})
-        super
-      end
+      cattr_accessor :edge, :version
 
       def block_code(code, language)
         <<-HTML
@@ -15,6 +15,16 @@ module RailsGuides
 HTML
       end
 
+      def link(url, title, content)
+        if url.start_with?("http://api.rubyonrails.org")
+          %(<a href="#{api_link(url)}">#{content}</a>)
+        elsif title
+          %(<a href="#{url}" title="#{title}">#{content}</a>)
+        else
+          %(<a href="#{url}">#{content}</a>)
+        end
+      end
+
       def header(text, header_level)
         # Always increase the heading level by 1, so we can use h1, h2 heading in the document
         header_level += 1
@@ -23,9 +33,11 @@ HTML
       end
 
       def paragraph(text)
-        if text =~ /^(TIP|IMPORTANT|CAUTION|WARNING|NOTE|INFO|TODO)[.:]/
+        if text =~ %r{^NOTE:\s+Defined\s+in\s+<code>(.*?)</code>\.?$}
+          %(<div class="note"><p>Defined in <code><a href="#{github_file_url($1)}">#{$1}</a></code>.</p></div>)
+        elsif text =~ /^(TIP|IMPORTANT|CAUTION|WARNING|NOTE|INFO|TODO)[.:]/
           convert_notes(text)
-        elsif text.include?('DO NOT READ THIS FILE ON GITHUB')
+        elsif text.include?("DO NOT READ THIS FILE ON GITHUB")
         elsif text =~ /^\[<sup>(\d+)\]:<\/sup> (.+)$/
           linkback = %(<a href="#footnote-#{$1}-ref"><sup>#{$1}</sup></a>)
           %(<p class="footnote" id="footnote-#{$1}">#{linkback} #{$2}</p>)
@@ -46,14 +58,14 @@ HTML
 
         def brush_for(code_type)
           case code_type
-            when 'ruby', 'sql', 'plain'
-              code_type
-            when 'erb', 'html+erb'
-              'ruby; html-script: true'
-            when 'html'
-              'xml' # HTML is understood, but there are .xml rules in the CSS
-            else
-              'plain'
+          when "ruby", "sql", "plain"
+            code_type
+          when "erb", "html+erb"
+            "ruby; html-script: true"
+          when "html"
+            "xml" # HTML is understood, but there are .xml rules in the CSS
+          else
+            "plain"
           end
         end
 
@@ -63,21 +75,49 @@ HTML
           #
           # It is important that we do not eat more than one newline
           # because formatting may be wrong otherwise. For example,
-          # if a bulleted list follows the first item is not rendered
+          # if a bulleted list follows, the first item is not rendered
           # as a list item, but as a paragraph starting with a plain
           # asterisk.
           body.gsub(/^(TIP|IMPORTANT|CAUTION|WARNING|NOTE|INFO|TODO)[.:](.*?)(\n(?=\n)|\Z)/m) do
-            css_class = case $1
-                        when 'CAUTION', 'IMPORTANT'
-                          'warning'
-                        when 'TIP'
-                          'info'
-                        else
-                          $1.downcase
-                        end
+            css_class = \
+              case $1
+              when "CAUTION", "IMPORTANT"
+                "warning"
+              when "TIP"
+                "info"
+              else
+                $1.downcase
+              end
             %(<div class="#{css_class}"><p>#{$2.strip}</p></div>)
           end
         end
+
+        def github_file_url(file_path)
+          tree = version || edge
+
+          root = file_path[%r{(\w+)/}, 1]
+          path = \
+            case root
+            when "abstract_controller", "action_controller", "action_dispatch"
+              "actionpack/lib/#{file_path}"
+            when /\A(action|active)_/
+              "#{root.sub("_", "")}/lib/#{file_path}"
+            else
+              file_path
+            end
+
+          "https://github.com/rails/rails/tree/#{tree}/#{path}"
+        end
+
+        def api_link(url)
+          if url =~ %r{http://api\.rubyonrails\.org/v\d+\.}
+            url
+          elsif edge
+            url.sub("api", "edgeapi")
+          else
+            url.sub(/(?<=\.org)/, "/#{version}")
+          end
+        end
     end
   end
 end
diff --git a/guides/source/2_2_release_notes.md b/guides/source/2_2_release_notes.md
index 79634d8760..ac5833e069 100644
--- a/guides/source/2_2_release_notes.md
+++ b/guides/source/2_2_release_notes.md
@@ -34,7 +34,7 @@ Documentation
 The internal documentation of Rails, in the form of code comments, has been improved in numerous places. In addition, the [Ruby on Rails Guides](http://guides.rubyonrails.org/) project is the definitive source for information on major Rails components. In its first official release, the Guides page includes:
 
 * [Getting Started with Rails](getting_started.html)
-* [Rails Database Migrations](migrations.html)
+* [Rails Database Migrations](active_record_migrations.html)
 * [Active Record Associations](association_basics.html)
 * [Active Record Query Interface](active_record_querying.html)
 * [Layouts and Rendering in Rails](layouts_and_rendering.html)
@@ -45,7 +45,6 @@ The internal documentation of Rails, in the form of code comments, has been impr
 * [A Guide to Testing Rails Applications](testing.html)
 * [Securing Rails Applications](security.html)
 * [Debugging Rails Applications](debugging_rails_applications.html)
-* [Performance Testing Rails Applications](performance_testing.html)
 * [The Basics of Creating Rails Plugins](plugins.html)
 
 All told, the Guides provide tens of thousands of words of guidance for beginning and intermediate Rails developers.
diff --git a/guides/source/2_3_release_notes.md b/guides/source/2_3_release_notes.md
index 06761b67bb..1020f4a8e7 100644
--- a/guides/source/2_3_release_notes.md
+++ b/guides/source/2_3_release_notes.md
@@ -10,7 +10,7 @@ Rails 2.3 delivers a variety of new and improved features, including pervasive R
 Application Architecture
 ------------------------
 
-There are two major changes in the architecture of Rails applications: complete integration of the [Rack](http://rack.github.io/) modular web server interface, and renewed support for Rails Engines.
+There are two major changes in the architecture of Rails applications: complete integration of the [Rack](https://rack.github.io/) modular web server interface, and renewed support for Rails Engines.
 
 ### Rack Integration
 
@@ -54,7 +54,7 @@ Documentation
 
 The [Ruby on Rails guides](http://guides.rubyonrails.org/) project has published several additional guides for Rails 2.3. In addition, a [separate site](http://edgeguides.rubyonrails.org/) maintains updated copies of the Guides for Edge Rails. Other documentation efforts include a relaunch of the [Rails wiki](http://newwiki.rubyonrails.org/) and early planning for a Rails Book.
 
-* More Information: [Rails Documentation Projects](http://weblog.rubyonrails.org/2009/1/15/rails-documentation-projects.)
+* More Information: [Rails Documentation Projects](http://weblog.rubyonrails.org/2009/1/15/rails-documentation-projects)
 
 Ruby 1.9.1 Support
 ------------------
@@ -231,7 +231,7 @@ Rails chooses between file, template, and action depending on whether there is a
 
 ### Application Controller Renamed
 
-If you're one of the people who has always been bothered by the special-case naming of `application.rb`, rejoice! It's been reworked to be application_controller.rb in Rails 2.3. In addition, there's a new rake task, `rake rails:update:application_controller` to do this automatically for you - and it will be run as part of the normal `rake rails:update` process.
+If you're one of the people who has always been bothered by the special-case naming of `application.rb`, rejoice! It's been reworked to be `application_controller.rb` in Rails 2.3. In addition, there's a new rake task, `rake rails:update:application_controller` to do this automatically for you - and it will be run as part of the normal `rake rails:update` process.
 
 * More Information:
     * [The Death of Application.rb](http://afreshcup.com/2008/11/17/rails-2x-the-death-of-applicationrb/)
@@ -304,7 +304,7 @@ Rails now keeps a per-request local cache of read from the remote cache stores,
 
 Rails can now provide localized views, depending on the locale that you have set. For example, suppose you have a `Posts` controller with a `show` action. By default, this will render `app/views/posts/show.html.erb`. But if you set `I18n.locale = :da`, it will render `app/views/posts/show.da.html.erb`. If the localized template isn't present, the undecorated version will be used. Rails also includes `I18n#available_locales` and `I18n::SimpleBackend#available_locales`, which return an array of the translations that are available in the current Rails project.
 
-In addition, you can use the same scheme to localize the rescue files in the `public` directory: `public/500.da.html` or `public/404.en.html` work, for example.
+In addition, you can use the same scheme to localize the rescue files in the public directory: `public/500.da.html` or `public/404.en.html` work, for example.
 
 ### Partial Scoping for Translations
 
diff --git a/guides/source/3_0_release_notes.md b/guides/source/3_0_release_notes.md
index 49d37ba489..f0e2cb3b63 100644
--- a/guides/source/3_0_release_notes.md
+++ b/guides/source/3_0_release_notes.md
@@ -88,7 +88,7 @@ $ cd myapp
 
 Rails now uses a `Gemfile` in the application root to determine the gems you require for your application to start. This `Gemfile` is processed by the [Bundler](https://github.com/bundler/bundler) which then installs all your dependencies. It can even install all the dependencies locally to your application so that it doesn't depend on the system gems.
 
-More information: - [bundler homepage](http://bundler.io/)
+More information: - [bundler homepage](https://bundler.io/)
 
 ### Living on the Edge
 
@@ -155,7 +155,7 @@ Documentation
 
 The documentation in the Rails tree is being updated with all the API changes, additionally, the [Rails Edge Guides](http://edgeguides.rubyonrails.org/) are being updated one by one to reflect the changes in Rails 3.0. The guides at [guides.rubyonrails.org](http://guides.rubyonrails.org/) however will continue to contain only the stable version of Rails (at this point, version 2.3.5, until 3.0 is released).
 
-More Information: - [Rails Documentation Projects](http://weblog.rubyonrails.org/2009/1/15/rails-documentation-projects.)
+More Information: - [Rails Documentation Projects](http://weblog.rubyonrails.org/2009/1/15/rails-documentation-projects)
 
 
 Internationalization
diff --git a/guides/source/3_1_release_notes.md b/guides/source/3_1_release_notes.md
index feee0f9920..17d4ac23b6 100644
--- a/guides/source/3_1_release_notes.md
+++ b/guides/source/3_1_release_notes.md
@@ -99,7 +99,7 @@ gem 'jquery-rails'
     # config.assets.manifest = YOUR_PATH
 
     # Precompile additional assets (application.js, application.css, and all non-JS/CSS are already added)
-    # config.assets.precompile `= %w( search.js )
+    # config.assets.precompile `= %w( admin.js admin.css )
 
 
     # Force all access to the app over SSL, use Strict-Transport-Security, and use secure cookies.
@@ -151,7 +151,7 @@ $ cd myapp
 
 Rails now uses a `Gemfile` in the application root to determine the gems you require for your application to start. This `Gemfile` is processed by the [Bundler](https://github.com/carlhuda/bundler) gem, which then installs all your dependencies. It can even install all the dependencies locally to your application so that it doesn't depend on the system gems.
 
-More information: - [bundler homepage](http://bundler.io/)
+More information: - [bundler homepage](https://bundler.io/)
 
 ### Living on the Edge
 
diff --git a/guides/source/3_2_release_notes.md b/guides/source/3_2_release_notes.md
index f16d509f77..ae6eb27f35 100644
--- a/guides/source/3_2_release_notes.md
+++ b/guides/source/3_2_release_notes.md
@@ -30,13 +30,13 @@ TIP: Note that Ruby 1.8.7 p248 and p249 have marshalling bugs that crash Rails.
 
 ### What to update in your apps
 
-* Update your Gemfile to depend on
+* Update your `Gemfile` to depend on
     * `rails = 3.2.0`
     * `sass-rails ~> 3.2.3`
     * `coffee-rails ~> 3.2.1`
     * `uglifier >= 1.0.3`
 
-* Rails 3.2 deprecates `vendor/plugins` and Rails 4.0 will remove them completely. You can start replacing these plugins by extracting them as gems and adding them in your Gemfile. If you choose not to make them gems, you can move them into, say, `lib/my_plugin/*` and add an appropriate initializer in `config/initializers/my_plugin.rb`.
+* Rails 3.2 deprecates `vendor/plugins` and Rails 4.0 will remove them completely. You can start replacing these plugins by extracting them as gems and adding them in your `Gemfile`. If you choose not to make them gems, you can move them into, say, `lib/my_plugin/*` and add an appropriate initializer in `config/initializers/my_plugin.rb`.
 
 * There are a couple of new configuration changes you'd want to add in `config/environments/development.rb`:
 
@@ -81,7 +81,7 @@ $ cd myapp
 
 Rails now uses a `Gemfile` in the application root to determine the gems you require for your application to start. This `Gemfile` is processed by the [Bundler](https://github.com/carlhuda/bundler) gem, which then installs all your dependencies. It can even install all the dependencies locally to your application so that it doesn't depend on the system gems.
 
-More information: [Bundler homepage](http://bundler.io/)
+More information: [Bundler homepage](https://bundler.io/)
 
 ### Living on the Edge
 
@@ -156,7 +156,7 @@ Railties
 
     will create indexes for `title` and `author` with the latter being a unique index. Some types such as decimal accept custom options. In the example, `price` will be a decimal column with precision and scale set to 7 and 2 respectively.
 
-* Turn gem has been removed from default Gemfile.
+* Turn gem has been removed from default `Gemfile`.
 
 * Remove old plugin generator `rails generate plugin` in favor of `rails plugin new` command.
 
@@ -295,7 +295,7 @@ Action Pack
     ```ruby
     @items.each do |item|
       content_tag_for(:li, item) do
-         Title: <%= item.title %>
+        Title: <%= item.title %>
       end
     end
     ```
diff --git a/guides/source/4_0_release_notes.md b/guides/source/4_0_release_notes.md
index 4615cf18e6..0921cd1979 100644
--- a/guides/source/4_0_release_notes.md
+++ b/guides/source/4_0_release_notes.md
@@ -36,7 +36,7 @@ $ cd myapp
 
 Rails now uses a `Gemfile` in the application root to determine the gems you require for your application to start. This `Gemfile` is processed by the [Bundler](https://github.com/carlhuda/bundler) gem, which then installs all your dependencies. It can even install all the dependencies locally to your application so that it doesn't depend on the system gems.
 
-More information: [Bundler homepage](http://bundler.io)
+More information: [Bundler homepage](https://bundler.io)
 
 ### Living on the Edge
 
@@ -60,13 +60,13 @@ Major Features
 ### Upgrade
 
 * **Ruby 1.9.3** ([commit](https://github.com/rails/rails/commit/a0380e808d3dbd2462df17f5d3b7fcd8bd812496)) - Ruby 2.0 preferred; 1.9.3+ required
-* **[New deprecation policy](http://www.youtube.com/watch?v=z6YgD6tVPQs)** - Deprecated features are warnings in Rails 4.0 and will be removed in Rails 4.1.
+* **[New deprecation policy](https://www.youtube.com/watch?v=z6YgD6tVPQs)** - Deprecated features are warnings in Rails 4.0 and will be removed in Rails 4.1.
 * **ActionPack page and action caching** ([commit](https://github.com/rails/rails/commit/b0a7068564f0c95e7ef28fc39d0335ed17d93e90)) - Page and action caching are extracted to a separate gem. Page and action caching requires too much manual intervention (manually expiring caches when the underlying model objects are updated). Instead, use Russian doll caching.
 * **ActiveRecord observers** ([commit](https://github.com/rails/rails/commit/ccecab3ba950a288b61a516bf9b6962e384aae0b)) - Observers are extracted to a separate gem. Observers are only needed for page and action caching, and can lead to spaghetti code.
 * **ActiveRecord session store** ([commit](https://github.com/rails/rails/commit/0ffe19056c8e8b2f9ae9d487b896cad2ce9387ad)) - The ActiveRecord session store is extracted to a separate gem. Storing sessions in SQL is costly. Instead, use cookie sessions, memcache sessions, or a custom session store.
 * **ActiveModel mass assignment protection** ([commit](https://github.com/rails/rails/commit/f8c9a4d3e88181cee644f91e1342bfe896ca64c6)) - Rails 3 mass assignment protection is deprecated. Instead, use strong parameters.
 * **ActiveResource** ([commit](https://github.com/rails/rails/commit/f1637bf2bb00490203503fbd943b73406e043d1d)) - ActiveResource is extracted to a separate gem. ActiveResource was not widely used.
-* **vendor/plugins removed** ([commit](https://github.com/rails/rails/commit/853de2bd9ac572735fa6cf59fcf827e485a231c3)) - Use a Gemfile to manage installed gems.
+* **vendor/plugins removed** ([commit](https://github.com/rails/rails/commit/853de2bd9ac572735fa6cf59fcf827e485a231c3)) - Use a `Gemfile` to manage installed gems.
 
 ### ActionPack
 
diff --git a/guides/source/4_1_release_notes.md b/guides/source/4_1_release_notes.md
index 6bf65757ec..2c5e665e33 100644
--- a/guides/source/4_1_release_notes.md
+++ b/guides/source/4_1_release_notes.md
@@ -274,7 +274,7 @@ for detailed changes.
 * The [Spring application
   preloader](https://github.com/rails/spring) is now installed
   by default for new applications. It uses the development group of
-  the Gemfile, so will not be installed in
+  the `Gemfile`, so will not be installed in
   production. ([Pull Request](https://github.com/rails/rails/pull/12958))
 
 * `BACKTRACE` environment variable to show unfiltered backtraces for test
diff --git a/guides/source/4_2_release_notes.md b/guides/source/4_2_release_notes.md
index a30bfc458a..7105df5634 100644
--- a/guides/source/4_2_release_notes.md
+++ b/guides/source/4_2_release_notes.md
@@ -179,7 +179,7 @@ change your code to use the explicit form (`render file: "foo/bar"`) instead.
 
 `respond_with` and the corresponding class-level `respond_to` have been moved
 to the [responders](https://github.com/plataformatec/responders) gem. Add
-`gem 'responders', '~> 2.0'` to your Gemfile to use it:
+`gem 'responders', '~> 2.0'` to your `Gemfile` to use it:
 
 ```ruby
 # app/controllers/users_controller.rb
@@ -368,7 +368,7 @@ Please refer to the [Changelog][railties] for detailed changes.
 
 ### Notable changes
 
-*   Introduced `web-console` in the default application Gemfile.
+*   Introduced `web-console` in the default application `Gemfile`.
     ([Pull Request](https://github.com/rails/rails/pull/11667))
 
 *   Added a `required` option to the model generator for associations.
diff --git a/guides/source/5_0_release_notes.md b/guides/source/5_0_release_notes.md
index 8bd2074e82..656838c6b8 100644
--- a/guides/source/5_0_release_notes.md
+++ b/guides/source/5_0_release_notes.md
@@ -49,13 +49,38 @@ client-side JavaScript framework and a server-side Ruby framework. You have
 access to your full domain model written with Active Record or your ORM of
 choice.
 
-See the [Active Cable Overview](action_cable_overview.html) guide for more
+See the [Action Cable Overview](action_cable_overview.html) guide for more
 information.
 
-### Rails API
-[Pull Request](https://github.com/rails/rails/pull/19832)
+### API Applications
 
-ToDo...
+Rails can now be used to create slimmed down API only applications.
+This is useful for creating and serving APIs similar to [Twitter](https://dev.twitter.com) or [GitHub](https://developer.github.com) API,
+that can be used to serve public facing, as well as, for custom applications.
+
+You can generate a new api Rails app using:
+
+```bash
+$ rails new my_api --api
+```
+
+This will do three main things:
+
+- Configure your application to start with a more limited set of middleware
+  than normal. Specifically, it will not include any middleware primarily useful
+  for browser applications (like cookies support) by default.
+- Make `ApplicationController` inherit from `ActionController::API` instead of
+  `ActionController::Base`. As with middleware, this will leave out any Action
+  Controller modules that provide functionalities primarily used by browser
+  applications.
+- Configure the generators to skip generating views, helpers and assets when
+  you generate a new resource.
+
+The application provides a base for APIs,
+that can then be [configured to pull in functionality](api_app.html) as suitable for the application's needs.
+
+See the [Using Rails for API-only Applications](api_app.html) guide for more
+information.
 
 ### Active Record attributes API
 
@@ -65,9 +90,10 @@ It also changes the behavior of values passed to `ActiveRecord::Base.where`, whi
 without having to rely on implementation details or monkey patching.
 
 Some things that you can achieve with this:
-* The type detected by Active Record can be overridden.
-* A default can also be provided.
-* Attributes do not need to be backed by a database column.
+
+- The type detected by Active Record can be overridden.
+- A default can also be provided.
+- Attributes do not need to be backed by a database column.
 
 ```ruby
 
@@ -99,14 +125,14 @@ store_listing.price_in_cents # => 10
 StoreListing.new.my_string # => "new default"
 StoreListing.new.my_default_proc # => 2015-05-30 11:04:48 -0600
 model = StoreListing.new(field_without_db_column: ["1", "2", "3"])
-model.attributes #=> {field_without_db_column: [1, 2, 3]}
+model.attributes # => {field_without_db_column: [1, 2, 3]}
 ```
 
 **Creating Custom Types:**
 
 You can define your own custom types, as long as they respond
-to the methods defined on the value type. The method +deserialize+ or
-+cast+ will be called on your type object, with raw input from the
+to the methods defined on the value type. The method `deserialize` or
+`cast` will be called on your type object, with raw input from the
 database or from your controllers. This is useful, for example, when doing custom conversion,
 like Money data.
 
@@ -114,7 +140,7 @@ like Money data.
 
 When `ActiveRecord::Base.where` is called, it will
 use the type defined by the model class to convert the value to SQL,
-calling +serialize+ on your type object.
+calling `serialize` on your type object.
 
 This gives the objects ability to specify, how to convert values when performing SQL queries.
 
@@ -124,15 +150,28 @@ The type of an attribute is given the opportunity to change how dirty
 tracking is performed.
 
 See its
-[documentation](http://api.rubyonrails.org/classes/ActiveRecord/Attributes/ClassMethods.html)
+[documentation](http://api.rubyonrails.org/v5.0.1/classes/ActiveRecord/Attributes/ClassMethods.html)
 for a detailed write up.
 
 
 ### Test Runner
-[Pull Request](https://github.com/rails/rails/pull/19216)
 
-ToDo...
+A new test runner has been introduced to enhance the capabilities of running tests from Rails.
+To use this test runner simply type `bin/rails test`.
 
+Test Runner is inspired from `RSpec`, `minitest-reporters`, `maxitest` and others.
+It includes some of these notable advancements:
+
+- Run a single test using line number of test.
+- Run multiple tests pinpointing to line number of tests.
+- Improved failure messages, which also add ease of re-running failed tests.
+- Fail fast using `-f` option, to stop tests immediately on occurrence of failure,
+instead of waiting for the suite to complete.
+- Defer test output until the end of a full test run using the `-d` option.
+- Complete exception backtrace output using `-b` option.
+- Integration with `Minitest` to allow options like `-s` for test seed data,
+`-n` for running specific test by name, `-v` for better verbose output and so forth.
+- Colored test output.
 
 Railties
 --------
@@ -167,13 +206,13 @@ Please refer to the [Changelog][railties] for detailed changes.
 
 *   Deprecated `config.static_cache_control` in favor of
     `config.public_file_server.headers`.
-    ([Pull Request](https://github.com/rails/rails/pull/22173))
+    ([Pull Request](https://github.com/rails/rails/pull/19135))
 
 *   Deprecated `config.serve_static_files` in favor of `config.public_file_server.enabled`.
     ([Pull Request](https://github.com/rails/rails/pull/22173))
 
 *   Deprecated the tasks in the `rails` task namespace in favor of the `app` namespace.
-    (e.g. `rails:update` and `rails:template` tasks is renamed to `app:update` and `app:template`.)
+    (e.g. `rails:update` and `rails:template` tasks are renamed to `app:update` and `app:template`.)
     ([Pull Request](https://github.com/rails/rails/pull/23439))
 
 ### Notable changes
@@ -203,7 +242,7 @@ Please refer to the [Changelog][railties] for detailed changes.
      [Pull Request](https://github.com/rails/rails/pull/22288))
 
 *   New applications are generated with the evented file system monitor enabled
-    on Linux and Mac OS X. The feature can be opted out by passing
+    on Linux and macOS. The feature can be opted out by passing
     `--skip-listen` to the generator.
     ([commit](https://github.com/rails/rails/commit/de6ad5665d2679944a9ee9407826ba88395a1003),
     [commit](https://github.com/rails/rails/commit/94dbc48887bf39c241ee2ce1741ee680d773f202))
@@ -219,7 +258,6 @@ Please refer to the [Changelog][railties] for detailed changes.
     Spring to watch additional common files.
     ([commit](https://github.com/rails/rails/commit/b04d07337fd7bc17e88500e9d6bcd361885a45f8))
 
-
 *   Added `--skip-action-mailer` to skip Action Mailer while generating new app.
     ([Pull Request](https://github.com/rails/rails/pull/18288))
 
@@ -229,6 +267,9 @@ Please refer to the [Changelog][railties] for detailed changes.
 *   Changed `_form.html.erb` generated by scaffold generator to use local variables.
     ([Pull Request](https://github.com/rails/rails/pull/13434))
 
+*   Disabled autoloading of classes in production environment.
+    ([commit](https://github.com/rails/rails/commit/a71350cae0082193ad8c66d65ab62e8bb0b7853b))
+
 Action Pack
 -----------
 
@@ -320,6 +361,15 @@ Please refer to the [Changelog][action-pack] for detailed changes.
 *   Deprecated `:controller` and `:action` path parameters.
     ([Pull Request](https://github.com/rails/rails/pull/23980))
 
+*   Deprecated env method on controller instances.
+    ([commit](https://github.com/rails/rails/commit/05934d24aff62d66fc62621aa38dae6456e276be))
+
+*   `ActionDispatch::ParamsParser` is deprecated and was removed from the
+    middleware stack. To configure the parameter parsers use
+    `ActionDispatch::Request.parameter_parsers=`.
+    ([commit](https://github.com/rails/rails/commit/38d2bf5fd1f3e014f2397898d371c339baa627b1),
+    [commit](https://github.com/rails/rails/commit/5ed38014811d4ce6d6f957510b9153938370173b))
+
 ### Notable changes
 
 *   Added `ActionController::Renderer` to render arbitrary templates
@@ -367,7 +417,7 @@ Please refer to the [Changelog][action-pack] for detailed changes.
     `ActionDispatch::IntegrationTest` instead.
     ([commit](https://github.com/rails/rails/commit/4414c5d1795e815b102571425974a8b1d46d932d))
 
-*   Rails will only generate "weak", instead of strong ETags.
+*   Rails generates weak ETags by default.
     ([Pull Request](https://github.com/rails/rails/pull/17573))
 
 *   Controller actions without an explicit `render` call and with no
@@ -382,11 +432,6 @@ Please refer to the [Changelog][action-pack] for detailed changes.
 *   Added request encoding and response parsing to integration tests.
     ([Pull Request](https://github.com/rails/rails/pull/21671))
 
-*   Update default rendering policies when the controller action did
-    not explicitly indicate a response.
-    ([Pull Request](https://github.com/rails/rails/pull/23827))
-
-
 *   Add `ActionController#helpers` to get access to the view context
     at the controller level.
     ([Pull Request](https://github.com/rails/rails/pull/24866))
@@ -394,6 +439,24 @@ Please refer to the [Changelog][action-pack] for detailed changes.
 *   Discarded flash messages get removed before storing into session.
     ([Pull Request](https://github.com/rails/rails/pull/18721))
 
+*   Added support for passing collection of records to `fresh_when` and
+    `stale?`.
+    ([Pull Request](https://github.com/rails/rails/pull/18374))
+
+*   `ActionController::Live` became an `ActiveSupport::Concern`. That
+    means it can't be just included in other modules without extending
+    them with `ActiveSupport::Concern` or `ActionController::Live`
+    won't take effect in production. Some people may be using another
+    module to include some special `Warden`/`Devise` authentication
+    failure handling code as well since the middleware can't catch a
+    `:warden` thrown by a spawned thread which is the case when using
+    `ActionController::Live`.
+    ([More details in this issue](https://github.com/rails/rails/issues/25581))
+
+*   Introduce `Response#strong_etag=` and `#weak_etag=` and analogous
+    options for `fresh_when` and `stale?`.
+    ([Pull Request](https://github.com/rails/rails/pull/24387))
+
 Action View
 -------------
 
@@ -413,13 +476,6 @@ Please refer to the [Changelog][action-view] for detailed changes.
     supported by I18n.
     ([Pull Request](https://github.com/rails/rails/pull/20019))
 
-### Deprecations
-
-*   Deprecated `datetime_field` and `datetime_field_tag` helpers.
-    Datetime input type was removed from HTML specification.
-    One can use `datetime_local_field` and `datetime_local_field_tag` instead.
-    ([Pull Request](https://github.com/rails/rails/pull/24385))
-
 ### Notable Changes
 
 *   Changed the default template handler from `ERB` to `Raw`.
@@ -439,6 +495,13 @@ Please refer to the [Changelog][action-view] for detailed changes.
 *   Partial template name no longer has to be a valid Ruby identifier.
     ([commit](https://github.com/rails/rails/commit/da9038e))
 
+*   The `datetime_tag` helper now generates an input tag with the type of
+    `datetime-local`.
+    ([Pull Request](https://github.com/rails/rails/pull/25469))
+
+*   Allow blocks while rendering with the `render partial:` helper.
+    ([Pull Request](https://github.com/rails/rails/pull/17974))
+
 Action Mailer
 -------------
 
@@ -524,8 +587,10 @@ Please refer to the [Changelog][active-record] for detailed changes.
     [activemodel-serializers-xml](https://github.com/rails/activemodel-serializers-xml)
     gem. ([Pull Request](https://github.com/rails/rails/pull/21161))
 
-*   Removed support for the legacy `mysql` database adapter from core. It will
-    live on in a separate gem for now, but most users should just use `mysql2`.
+*   Removed support for the legacy `mysql` database adapter from core. Most users should
+    be able to use `mysql2`. It will be converted to a separate gem when we find someone
+    to maintain it. ([Pull Request 1](https://github.com/rails/rails/pull/22642),
+    [Pull Request 2](https://github.com/rails/rails/pull/22715))
 
 *   Removed support for the `protected_attributes` gem.
     ([commit](https://github.com/rails/rails/commit/f4fbc0301021f13ae05c8e941c8efc4ae351fdf9))
@@ -536,6 +601,9 @@ Please refer to the [Changelog][active-record] for detailed changes.
 *   Removed support for `activerecord-deprecated_finders` gem.
     ([commit](https://github.com/rails/rails/commit/78dab2a8569408658542e462a957ea5a35aa4679))
 
+*   Removed `ActiveRecord::ConnectionAdapters::Column::TRUE_VALUES` constant.
+    ([commit](https://github.com/rails/rails/commit/a502703c3d2151d4d3b421b29fefdac5ad05df61))
+
 ### Deprecations
 
 *   Deprecated passing a class as a value in a query. Users should pass strings
@@ -597,6 +665,14 @@ Please refer to the [Changelog][active-record] for detailed changes.
     `use_transactional_tests` for more clarity.
     ([Pull Request](https://github.com/rails/rails/pull/19282))
 
+*   Deprecated passing a column to `ActiveRecord::Connection#quote`.
+    ([commit](https://github.com/rails/rails/commit/7bb620869725ad6de603f6a5393ee17df13aa96c))
+
+*   Added an option `end` to `find_in_batches` that complements the `start`
+    parameter to specify where to stop batch processing.
+    ([Pull Request](https://github.com/rails/rails/pull/12257))
+
+
 ### Notable changes
 
 *   Added a `foreign_key` option to `references` while creating the table.
@@ -631,9 +707,6 @@ Please refer to the [Changelog][active-record] for detailed changes.
     operator to combine WHERE or HAVING clauses.
     ([commit](https://github.com/rails/rails/commit/b0b37942d729b6bdcd2e3178eda7fa1de203b3d0))
 
-*   Added `:time` option added for `#touch`.
-    ([Pull Request](https://github.com/rails/rails/pull/18956))
-
 *   Added `ActiveRecord::Base.suppress` to prevent the receiver from being saved
     during the given block.
     ([Pull Request](https://github.com/rails/rails/pull/18910))
@@ -702,7 +775,7 @@ Please refer to the [Changelog][active-record] for detailed changes.
 
 *   Added prepared statements support to `mysql2` adapter, for mysql2 0.4.4+,
     Previously this was only supported on the deprecated `mysql` legacy adapter.
-    To enable, set `prepared_statements: true` in config/database.yml.
+    To enable, set `prepared_statements: true` in `config/database.yml`.
     ([Pull Request](https://github.com/rails/rails/pull/23461))
 
 *   Added ability to call `ActionRecord::Relation#update` on relation objects
@@ -719,6 +792,29 @@ Please refer to the [Changelog][active-record] for detailed changes.
 *   Added `:index_errors` option to add indexes to errors of nested attributes.
     ([Pull Request](https://github.com/rails/rails/pull/19686))
 
+*   Added support for bidirectional destroy dependencies.
+    ([Pull Request](https://github.com/rails/rails/pull/18548))
+
+*   Added support for `after_commit` callbacks in transactional tests.
+    ([Pull Request](https://github.com/rails/rails/pull/18458))
+
+*   Added `foreign_key_exists?` method to see if a foreign key exists on a table
+    or not.
+    ([Pull Request](https://github.com/rails/rails/pull/18662))
+
+*   Added `:time` option to `touch` method to touch records with different time
+    than the current time.
+    ([Pull Request](https://github.com/rails/rails/pull/18956))
+
+*   Change transaction callbacks to not swallow errors.
+    Before this change any errors raised inside a transaction callback
+    were getting rescued and printed in the logs, unless you used
+    the (newly deprecated) `raise_in_transactional_callbacks = true` option.
+
+    Now these errors are not rescued anymore and just bubble up, matching the
+    behavior of other callbacks.
+    ([commit](https://github.com/rails/rails/commit/07d3d402341e81ada0214f2cb2be1da69eadfe72))
+
 Active Model
 ------------
 
@@ -772,6 +868,9 @@ Please refer to the [Changelog][active-model] for detailed changes.
 *   Validate multiple contexts on `valid?` and `invalid?` at once.
     ([Pull Request](https://github.com/rails/rails/pull/21069))
 
+*   Change `validates_acceptance_of` to accept `true` as default value
+    apart from `1`.
+    ([Pull Request](https://github.com/rails/rails/pull/18439))
 
 Active Job
 -----------
@@ -873,8 +972,10 @@ Please refer to the [Changelog][active-support] for detailed changes.
     `ActiveSupport::Cache::MemCachedStore#escape_key`, and
     `ActiveSupport::Cache::FileStore#key_file_path`.
     Use `normalize_key` instead.
+    ([Pull Request](https://github.com/rails/rails/pull/22215),
+     [commit](https://github.com/rails/rails/commit/a8f773b0))
 
-    Deprecated `ActiveSupport::Cache::LocaleCache#set_cache_value` in favor of `write_cache_value`.
+*   Deprecated `ActiveSupport::Cache::LocaleCache#set_cache_value` in favor of `write_cache_value`.
     ([Pull Request](https://github.com/rails/rails/pull/22215))
 
 *   Deprecated passing arguments to `assert_nothing_raised`.
@@ -905,7 +1006,8 @@ Please refer to the [Changelog][active-support] for detailed changes.
 
 *   Added `#on_weekend?`, `#on_weekday?`, `#next_weekday`, `#prev_weekday` methods to `Date`,
     `Time`, and `DateTime`.
-    ([Pull Request](https://github.com/rails/rails/pull/18335))
+    ([Pull Request](https://github.com/rails/rails/pull/18335),
+     [Pull Request](https://github.com/rails/rails/pull/23687))
 
 *   Added `same_time` option to `#next_week` and `#prev_week` for `Date`, `Time`,
     and `DateTime`.
@@ -913,7 +1015,7 @@ Please refer to the [Changelog][active-support] for detailed changes.
 
 *   Added `#prev_day` and `#next_day` counterparts to `#yesterday` and
     `#tomorrow` for `Date`, `Time`, and `DateTime`.
-    ([Pull Request](httpshttps://github.com/rails/rails/pull/18335))
+    ([Pull Request](https://github.com/rails/rails/pull/18335))
 
 *   Added `SecureRandom.base58` for generation of random base58 strings.
     ([commit](https://github.com/rails/rails/commit/b1093977110f18ae0cafe56c3d99fc22a7d54d1b))
@@ -956,9 +1058,6 @@ Please refer to the [Changelog][active-support] for detailed changes.
 *   Added `Array#second_to_last` and `Array#third_to_last` methods.
     ([Pull Request](https://github.com/rails/rails/pull/23583))
 
-*   Added `#on_weekday?` method to `Date`, `Time`, and `DateTime`.
-    ([Pull Request](https://github.com/rails/rails/pull/23687))
-
 *   Publish `ActiveSupport::Executor` and `ActiveSupport::Reloader` APIs to allow
     components and libraries to manage, and participate in, the execution of
     application code, and the application reloading process.
@@ -967,6 +1066,13 @@ Please refer to the [Changelog][active-support] for detailed changes.
 *   `ActiveSupport::Duration` now supports ISO8601 formatting and parsing.
     ([Pull Request](https://github.com/rails/rails/pull/16917))
 
+*   `ActiveSupport::JSON.decode` now supports parsing ISO8601 local times when
+    `parse_json_times` is enabled.
+    ([Pull Request](https://github.com/rails/rails/pull/23011))
+
+*   `ActiveSupport::JSON.decode` now return `Date` objects for date strings.
+    ([Pull Request](https://github.com/rails/rails/pull/23011))
+
 *   Added ability to `TaggedLogging` to allow loggers to be instantiated multiple
     times so that they don't share tags with each other.
     ([Pull Request](https://github.com/rails/rails/pull/9065))
diff --git a/guides/source/5_1_release_notes.md b/guides/source/5_1_release_notes.md
new file mode 100644
index 0000000000..852d04b1f6
--- /dev/null
+++ b/guides/source/5_1_release_notes.md
@@ -0,0 +1,659 @@
+**DO NOT READ THIS FILE ON GITHUB, GUIDES ARE PUBLISHED ON http://guides.rubyonrails.org.**
+
+Ruby on Rails 5.1 Release Notes
+===============================
+
+Highlights in Rails 5.1:
+
+* Yarn Support
+* Optional Webpack support
+* jQuery no longer a default dependency
+* System tests
+* Encrypted secrets
+* Parameterized mailers
+* Direct & resolved routes
+* Unification of form_for and form_tag into form_with
+
+These release notes cover only the major changes. To learn about various bug
+fixes and changes, please refer to the change logs or check out the [list of
+commits](https://github.com/rails/rails/commits/5-1-stable) in the main Rails
+repository on GitHub.
+
+--------------------------------------------------------------------------------
+
+Upgrading to Rails 5.1
+----------------------
+
+If you're upgrading an existing application, it's a great idea to have good test
+coverage before going in. You should also first upgrade to Rails 5.0 in case you
+haven't and make sure your application still runs as expected before attempting
+an update to Rails 5.1. A list of things to watch out for when upgrading is
+available in the
+[Upgrading Ruby on Rails](upgrading_ruby_on_rails.html#upgrading-from-rails-5-0-to-rails-5-1)
+guide.
+
+
+Major Features
+--------------
+
+### Yarn Support
+
+[Pull Request](https://github.com/rails/rails/pull/26836)
+
+Rails 5.1 allows managing JavaScript dependencies
+from NPM via Yarn. This will make it easy to use libraries like React, VueJS
+or any other library from NPM world. The Yarn support is integrated with
+the asset pipeline so that all dependencies will work seamlessly with the
+Rails 5.1 app.
+
+### Optional Webpack support
+
+[Pull Request](https://github.com/rails/rails/pull/27288)
+
+Rails apps can integrate with [Webpack](https://webpack.js.org/), a JavaScript
+asset bundler, more easily using the new [Webpacker](https://github.com/rails/webpacker)
+gem. Use the `--webpack` flag when generating new applications to enable Webpack
+integration.
+
+This is fully compatible with the asset pipeline, which you can continue to use for
+images, fonts, sounds, and other assets. You can even have some JavaScript code
+managed by the asset pipeline, and other code processed via Webpack. All of this is managed
+by Yarn, which is enabled by default.
+
+### jQuery no longer a default dependency
+
+[Pull Request](https://github.com/rails/rails/pull/27113)
+
+jQuery was required by default in earlier versions of Rails to provide features
+like `data-remote`, `data-confirm` and other parts of Rails' Unobtrusive JavaScript
+offerings. It is no longer required, as the UJS has been rewritten to use plain,
+vanilla JavaScript. This code now ships inside of Action View as
+`rails-ujs`.
+
+You can still use jQuery if needed, but it is no longer required by default.
+
+### System tests
+
+[Pull Request](https://github.com/rails/rails/pull/26703)
+
+Rails 5.1 has baked-in support for writing Capybara tests, in the form of
+System tests. You no longer need to worry about configuring Capybara and
+database cleaning strategies for such tests. Rails 5.1 provides a wrapper
+for running tests in Chrome with additional features such as failure
+screenshots.
+
+### Encrypted secrets
+
+[Pull Request](https://github.com/rails/rails/pull/28038)
+
+Rails now allows management of application secrets in a secure way,
+inspired by the [sekrets](https://github.com/ahoward/sekrets) gem.
+
+Run `bin/rails secrets:setup` to setup a new encrypted secrets file. This will
+also generate a master key, which must be stored outside of the repository. The
+secrets themselves can then be safely checked into the revision control system,
+in an encrypted form.
+
+Secrets will be decrypted in production, using a key stored either in the
+`RAILS_MASTER_KEY` environment variable, or in a key file.
+
+### Parameterized mailers
+
+[Pull Request](https://github.com/rails/rails/pull/27825)
+
+Allows specifying common parameters used for all methods in a mailer class in
+order to share instance variables, headers and other common setup.
+
+``` ruby
+class InvitationsMailer < ApplicationMailer
+  before_action { @inviter, @invitee = params[:inviter], params[:invitee] }
+  before_action { @account = params[:inviter].account }
+
+  def account_invitation
+    mail subject: "#{@inviter.name} invited you to their Basecamp (#{@account.name})"
+  end
+end
+
+InvitationsMailer.with(inviter: person_a, invitee: person_b)
+                 .account_invitation.deliver_later
+```
+
+### Direct & resolved routes
+
+[Pull Request](https://github.com/rails/rails/pull/23138)
+
+Rails 5.1 adds two new methods, `resolve` and `direct`, to the routing
+DSL. The `resolve` method allows customizing polymorphic mapping of models.
+
+``` ruby
+resource :basket
+
+resolve("Basket") { [:basket] }
+```
+
+``` erb
+<%= form_for @basket do |form| %>
+  <!-- basket form -->
+<% end %>
+```
+
+This will generate the singular URL `/basket` instead of the usual `/baskets/:id`.
+
+The `direct` method allows creation of custom URL helpers.
+
+``` ruby
+direct(:homepage) { "http://www.rubyonrails.org" }
+
+>> homepage_url
+=> "http://www.rubyonrails.org"
+```
+
+The return value of the block must be a valid argument for the `url_for`
+method. So, you can pass a valid string URL, Hash, Array, an
+Active Model instance, or an Active Model class.
+
+``` ruby
+direct :commentable do |model|
+  [ model, anchor: model.dom_id ]
+end
+
+direct :main do
+  { controller: 'pages', action: 'index', subdomain: 'www' }
+end
+```
+
+### Unification of form_for and form_tag into form_with
+
+[Pull Request](https://github.com/rails/rails/pull/26976)
+
+Before Rails 5.1, there were two interfaces for handling HTML forms:
+`form_for` for model instances and `form_tag` for custom URLs.
+
+Rails 5.1 combines both of these interfaces with `form_with`, and
+can generate form tags based on URLs, scopes or models.
+
+Using just a URL:
+
+``` erb
+<%= form_with url: posts_path do |form| %>
+  <%= form.text_field :title %>
+<% end %>
+
+<%# Will generate %>
+
+<form action="/posts" method="post" data-remote="true">
+  <input type="text" name="title">
+</form>
+```
+
+Adding a scope prefixes the input field names:
+
+``` erb
+<%= form_with scope: :post, url: posts_path do |form| %>
+  <%= form.text_field :title %>
+<% end %>
+
+<%# Will generate %>
+
+<form action="/posts" method="post" data-remote="true">
+  <input type="text" name="post[title]">
+</form>
+```
+
+Using a model infers both the URL and scope:
+
+``` erb
+<%= form_with model: Post.new do |form| %>
+  <%= form.text_field :title %>
+<% end %>
+
+<%# Will generate %>
+
+<form action="/posts" method="post" data-remote="true">
+  <input type="text" name="post[title]">
+</form>
+```
+
+An existing model makes an update form and fills out field values:
+
+``` erb
+<%= form_with model: Post.first do |form| %>
+  <%= form.text_field :title %>
+<% end %>
+
+<%# Will generate %>
+
+<form action="/posts/1" method="post" data-remote="true">
+  <input type="hidden" name="_method" value="patch">
+  <input type="text" name="post[title]" value="<the title of the post>">
+</form>
+```
+
+Incompatibilities
+-----------------
+
+The following changes may require immediate action upon upgrade.
+
+### Transactional tests with multiple connections
+
+Transactional tests now wrap all Active Record connections in database
+transactions.
+
+When a test spawns additional threads, and those threads obtain database
+connections, those connections are now handled specially:
+
+The threads will share a single connection, which is inside the managed
+transaction. This ensures all threads see the database in the same
+state, ignoring the outermost transaction. Previously, such additional
+connections were unable to see the fixture rows, for example.
+
+When a thread enters a nested transaction, it will temporarily obtain
+exclusive use of the connection, to maintain isolation.
+
+If your tests currently rely on obtaining a separate,
+outside-of-transaction, connection in a spawned thread, you'll need to
+switch to more explicit connection management.
+
+If your tests spawn threads and those threads interact while also using
+explicit database transactions, this change may introduce a deadlock.
+
+The easy way to opt out of this new behavior is to disable transactional
+tests on any test cases it affects.
+
+Railties
+--------
+
+Please refer to the [Changelog][railties] for detailed changes.
+
+### Removals
+
+*   Remove deprecated `config.static_cache_control`.
+    ([commit](https://github.com/rails/rails/commit/c861decd44198f8d7d774ee6a74194d1ac1a5a13))
+
+*   Remove deprecated `config.serve_static_files`.
+    ([commit](https://github.com/rails/rails/commit/0129ca2eeb6d5b2ea8c6e6be38eeb770fe45f1fa))
+
+*   Remove deprecated file `rails/rack/debugger`.
+    ([commit](https://github.com/rails/rails/commit/7563bf7b46e6f04e160d664e284a33052f9804b8))
+
+*   Remove deprecated tasks: `rails:update`, `rails:template`, `rails:template:copy`,
+    `rails:update:configs` and `rails:update:bin`.
+    ([commit](https://github.com/rails/rails/commit/f7782812f7e727178e4a743aa2874c078b722eef))
+
+*   Remove deprecated `CONTROLLER` environment variable for `routes` task.
+    ([commit](https://github.com/rails/rails/commit/f9ed83321ac1d1902578a0aacdfe55d3db754219))
+
+*   Remove -j (--javascript) option from `rails new` command.
+    ([Pull Request](https://github.com/rails/rails/pull/28546))
+
+### Notable changes
+
+*   Added a shared section to `config/secrets.yml` that will be loaded for all
+    environments.
+    ([commit](https://github.com/rails/rails/commit/e530534265d2c32b5c5f772e81cb9002dcf5e9cf))
+
+*   The config file `config/secrets.yml` is now loaded in with all keys as symbols.
+    ([Pull Request](https://github.com/rails/rails/pull/26929))
+
+*   Removed jquery-rails from default stack. rails-ujs, which is shipped
+    with Action View, is included as default UJS adapter.
+    ([Pull Request](https://github.com/rails/rails/pull/27113))
+
+*   Add Yarn support in new apps with a yarn binstub and package.json.
+    ([Pull Request](https://github.com/rails/rails/pull/26836))
+
+*   Add Webpack support in new apps via the `--webpack` option, which will delegate
+    to the rails/webpacker gem.
+    ([Pull Request](https://github.com/rails/rails/pull/27288))
+
+*   Initialize Git repo when generating new app, if option `--skip-git` is not
+    provided.
+    ([Pull Request](https://github.com/rails/rails/pull/27632))
+
+*   Add encrypted secrets in `config/secrets.yml.enc`.
+    ([Pull Request](https://github.com/rails/rails/pull/28038))
+
+*   Display railtie class name in `rails initializers`.
+    ([Pull Request](https://github.com/rails/rails/pull/25257))
+
+Action Cable
+-----------
+
+Please refer to the [Changelog][action-cable] for detailed changes.
+
+### Notable changes
+
+*   Added support for `channel_prefix` to Redis and evented Redis adapters
+    in `cable.yml` to avoid name collisions when using the same Redis server
+    with multiple applications.
+    ([Pull Request](https://github.com/rails/rails/pull/27425))
+
+*   Add `ActiveSupport::Notifications` hook for broadcasting data.
+    ([Pull Request](https://github.com/rails/rails/pull/24988))
+
+Action Pack
+-----------
+
+Please refer to the [Changelog][action-pack] for detailed changes.
+
+### Removals
+
+*   Removed support for non-keyword arguments in `#process`, `#get`, `#post`,
+    `#patch`, `#put`, `#delete`, and `#head` for the `ActionDispatch::IntegrationTest`
+    and `ActionController::TestCase` classes.
+    ([Commit](https://github.com/rails/rails/commit/98b8309569a326910a723f521911e54994b112fb),
+    [Commit](https://github.com/rails/rails/commit/de9542acd56f60d281465a59eac11e15ca8b3323))
+
+*   Removed deprecated `ActionDispatch::Callbacks.to_prepare` and
+    `ActionDispatch::Callbacks.to_cleanup`.
+    ([Commit](https://github.com/rails/rails/commit/3f2b7d60a52ffb2ad2d4fcf889c06b631db1946b))
+
+*   Removed deprecated methods related to controller filters.
+    ([Commit](https://github.com/rails/rails/commit/d7be30e8babf5e37a891522869e7b0191b79b757))
+    
+*   Removed deprecated support to `:text` and `:nothing` in `render`.
+    ([Commit](https://github.com/rails/rails/commit/79a5ea9eadb4d43b62afacedc0706cbe88c54496), 
+    [Commit](https://github.com/rails/rails/commit/57e1c99a280bdc1b324936a690350320a1cd8111))
+
+*   Removed deprecated support for calling `HashWithIndifferentAccess` methods on `ActionController::Parameters`.
+    ([Commit](https://github.com/rails/rails/pull/26746/commits/7093ceb480ad6a0a91b511832dad4c6a86981b93))
+
+### Deprecations
+
+*   Deprecated `config.action_controller.raise_on_unfiltered_parameters`.
+    It doesn't have any effect in Rails 5.1.
+    ([Commit](https://github.com/rails/rails/commit/c6640fb62b10db26004a998d2ece98baede509e5))
+
+### Notable changes
+
+*   Added the `direct` and `resolve` methods to the routing DSL.
+    ([Pull Request](https://github.com/rails/rails/pull/23138))
+
+*   Added a new `ActionDispatch::SystemTestCase` class to write system tests in
+    your applications.
+    ([Pull Request](https://github.com/rails/rails/pull/26703))
+
+Action View
+-------------
+
+Please refer to the [Changelog][action-view] for detailed changes.
+
+### Removals
+
+*   Removed deprecated `#original_exception` in `ActionView::Template::Error`.
+    ([commit](https://github.com/rails/rails/commit/b9ba263e5aaa151808df058f5babfed016a1879f))
+
+*   Remove the option `encode_special_chars` misnomer from `strip_tags`.
+    ([Pull Request](https://github.com/rails/rails/pull/28061))
+
+### Deprecations
+
+*   Deprecated Erubis ERB handler in favor of Erubi.
+    ([Pull Request](https://github.com/rails/rails/pull/27757))
+
+### Notable changes
+
+*   Raw template handler (the default template handler in Rails 5) now outputs
+    HTML-safe strings.
+    ([commit](https://github.com/rails/rails/commit/1de0df86695f8fa2eeae6b8b46f9b53decfa6ec8))
+
+*   Change `datetime_field` and `datetime_field_tag` to generate `datetime-local`
+    fields.
+    ([Pull Request](https://github.com/rails/rails/pull/28061))
+
+*   New Builder-style syntax for HTML tags (`tag.div`, `tag.br`, etc.)
+    ([Pull Request](https://github.com/rails/rails/pull/25543))
+
+*   Add `form_with` to unify `form_tag` and `form_for` usage.
+    ([Pull Request](https://github.com/rails/rails/pull/26976))
+
+*   Add `check_parameters` option to `current_page?`.
+    ([Pull Request](https://github.com/rails/rails/pull/27549))
+
+Action Mailer
+-------------
+
+Please refer to the [Changelog][action-mailer] for detailed changes.
+
+### Notable changes
+
+*   Allowed setting custom content type when attachments are included
+    and body is set inline.
+    ([Pull Request](https://github.com/rails/rails/pull/27227))
+
+*   Allowed passing lambdas as values to the `default` method.
+    ([Commit](https://github.com/rails/rails/commit/1cec84ad2ddd843484ed40b1eb7492063ce71baf))
+
+*   Added support for parameterized invocation of mailers to share before filters and defaults
+    between different mailer actions.
+    ([Commit](https://github.com/rails/rails/commit/1cec84ad2ddd843484ed40b1eb7492063ce71baf))
+
+*   Passed the incoming arguments to the mailer action to `process.action_mailer` event under
+    an `args` key.
+    ([Pull Request](https://github.com/rails/rails/pull/27900))
+
+Active Record
+-------------
+
+Please refer to the [Changelog][active-record] for detailed changes.
+
+### Removals
+
+*   Removed support for passing arguments and block at the same time to
+    `ActiveRecord::QueryMethods#select`.
+    ([Commit](https://github.com/rails/rails/commit/4fc3366d9d99a0eb19e45ad2bf38534efbf8c8ce))
+
+*   Removed deprecated `activerecord.errors.messages.restrict_dependent_destroy.one` and
+    `activerecord.errors.messages.restrict_dependent_destroy.many` i18n scopes.
+    ([Commit](https://github.com/rails/rails/commit/00e3973a311))
+
+*   Removed deprecated force reload argument in singular and collection association readers.
+    ([Commit](https://github.com/rails/rails/commit/09cac8c67af))
+
+*   Removed deprecated support for passing a column to `#quote`.
+    ([Commit](https://github.com/rails/rails/commit/e646bad5b7c))
+
+*   Removed deprecated `name` arguments from `#tables`.
+    ([Commit](https://github.com/rails/rails/commit/d5be101dd02214468a27b6839ffe338cfe8ef5f3))
+
+*   Removed deprecated behavior of `#tables` and `#table_exists?` to return tables and views
+    to return only tables and not views.
+    ([Commit](https://github.com/rails/rails/commit/5973a984c369a63720c2ac18b71012b8347479a8))
+
+*   Removed deprecated `original_exception` argument in `ActiveRecord::StatementInvalid#initialize`
+    and `ActiveRecord::StatementInvalid#original_exception`.
+    ([Commit](https://github.com/rails/rails/commit/bc6c5df4699d3f6b4a61dd12328f9e0f1bd6cf46))
+
+*   Removed deprecated support of passing a class as a value in a query.
+    ([Commit](https://github.com/rails/rails/commit/b4664864c972463c7437ad983832d2582186e886))
+
+*   Removed deprecated support to query using commas on LIMIT.
+    ([Commit](https://github.com/rails/rails/commit/fc3e67964753fb5166ccbd2030d7382e1976f393))
+
+*   Removed deprecated `conditions` parameter from `#destroy_all`.
+    ([Commit](https://github.com/rails/rails/commit/d31a6d1384cd740c8518d0bf695b550d2a3a4e9b))
+
+*   Removed deprecated `conditions` parameter from `#delete_all`.
+    ([Commit](https://github.com/rails/rails/pull/27503/commits/e7381d289e4f8751dcec9553dcb4d32153bd922b))
+
+*   Removed deprecated method `#load_schema_for` in favor of `#load_schema`.
+    ([Commit](https://github.com/rails/rails/commit/419e06b56c3b0229f0c72d3e4cdf59d34d8e5545))
+
+*   Removed deprecated `#raise_in_transactional_callbacks` configuration.
+    ([Commit](https://github.com/rails/rails/commit/8029f779b8a1dd9848fee0b7967c2e0849bf6e07))
+
+*   Removed deprecated `#use_transactional_fixtures` configuration.
+    ([Commit](https://github.com/rails/rails/commit/3955218dc163f61c932ee80af525e7cd440514b3))
+
+### Deprecations
+
+*   Deprecated `error_on_ignored_order_or_limit` flag in favor of
+    `error_on_ignored_order`.
+    ([Commit](https://github.com/rails/rails/commit/451437c6f57e66cc7586ec966e530493927098c7))
+
+*   Deprecated `sanitize_conditions` in favor of `sanitize_sql`.
+    ([Pull Request](https://github.com/rails/rails/pull/25999))
+
+*   Deprecated `supports_migrations?` on connection adapters.
+    ([Pull Request](https://github.com/rails/rails/pull/28172))
+
+*   Deprecated `Migrator.schema_migrations_table_name`, use `SchemaMigration.table_name` instead.
+    ([Pull Request](https://github.com/rails/rails/pull/28351))
+
+*   Deprecated using `#quoted_id` in quoting and type casting.
+    ([Pull Request](https://github.com/rails/rails/pull/27962))
+
+*   Deprecated passing `default` argument to `#index_name_exists?`.
+    ([Pull Request](https://github.com/rails/rails/pull/26930))
+
+### Notable changes
+
+*   Change Default Primary Keys to BIGINT.
+    ([Pull Request](https://github.com/rails/rails/pull/26266))
+
+*   Virtual/generated column support for MySQL 5.7.5+ and MariaDB 5.2.0+.
+    ([Commit](https://github.com/rails/rails/commit/65bf1c60053e727835e06392d27a2fb49665484c))
+
+*   Added support for limits in batch processing.
+    ([Commit](https://github.com/rails/rails/commit/451437c6f57e66cc7586ec966e530493927098c7))
+
+*   Transactional tests now wrap all Active Record connections in database
+    transactions.
+    ([Pull Request](https://github.com/rails/rails/pull/28726))
+
+*   Skipped comments in the output of `mysqldump` command by default.
+    ([Pull Request](https://github.com/rails/rails/pull/23301))
+
+*   Fixed `ActiveRecord::Relation#count` to use Ruby's `Enumerable#count` for counting
+    records when a block is passed as argument instead of silently ignoring the
+    passed block.
+    ([Pull Request](https://github.com/rails/rails/pull/24203))
+
+*   Pass `"-v ON_ERROR_STOP=1"` flag with `psql` command to not suppress SQL errors.
+    ([Pull Request](https://github.com/rails/rails/pull/24773))
+
+*   Add `ActiveRecord::Base.connection_pool.stat`.
+    ([Pull Request](https://github.com/rails/rails/pull/26988))
+
+*   Inheriting directly from `ActiveRecord::Migration` raises an error.
+    Specify the Rails version for which the migration was written for.
+    ([Commit](https://github.com/rails/rails/commit/249f71a22ab21c03915da5606a063d321f04d4d3))
+
+*   An error is raised when `through` association has ambiguous reflection name.
+    ([Commit](https://github.com/rails/rails/commit/0944182ad7ed70d99b078b22426cbf844edd3f61))
+
+Active Model
+------------
+
+Please refer to the [Changelog][active-model] for detailed changes.
+
+### Removals
+
+*   Removed deprecated methods in `ActiveModel::Errors`.
+    ([commit](https://github.com/rails/rails/commit/9de6457ab0767ebab7f2c8bc583420fda072e2bd))
+
+*   Removed deprecated `:tokenizer` option in the length validator.
+    ([commit](https://github.com/rails/rails/commit/6a78e0ecd6122a6b1be9a95e6c4e21e10e429513))
+
+*   Remove deprecated behavior that halts callbacks when the return value is false.
+    ([commit](https://github.com/rails/rails/commit/3a25cdca3e0d29ee2040931d0cb6c275d612dffe))
+
+### Notable changes
+
+*   The original string assigned to a model attribute is no longer incorrectly
+    frozen.
+    ([Pull Request](https://github.com/rails/rails/pull/28729))
+
+Active Job
+-----------
+
+Please refer to the [Changelog][active-job] for detailed changes.
+
+### Removals
+
+*   Removed deprecated support to passing the adapter class to `.queue_adapter`.
+    ([commit](https://github.com/rails/rails/commit/d1fc0a5eb286600abf8505516897b96c2f1ef3f6))
+
+*   Removed deprecated `#original_exception` in `ActiveJob::DeserializationError`.
+    ([commit](https://github.com/rails/rails/commit/d861a1fcf8401a173876489d8cee1ede1cecde3b))
+
+### Notable changes
+
+*   Added declarative exception handling via `ActiveJob::Base.retry_on` and `ActiveJob::Base.discard_on`.
+    ([Pull Request](https://github.com/rails/rails/pull/25991))
+
+*   Yield the job instance so you have access to things like `job.arguments` on
+    the custom logic after retries fail.
+    ([commit](https://github.com/rails/rails/commit/a1e4c197cb12fef66530a2edfaeda75566088d1f))
+
+Active Support
+--------------
+
+Please refer to the [Changelog][active-support] for detailed changes.
+
+### Removals
+
+*   Removed the `ActiveSupport::Concurrency::Latch` class.
+    ([Commit](https://github.com/rails/rails/commit/0d7bd2031b4054fbdeab0a00dd58b1b08fb7fea6))
+
+*   Removed `halt_callback_chains_on_return_false`.
+    ([Commit](https://github.com/rails/rails/commit/4e63ce53fc25c3bc15c5ebf54bab54fa847ee02a))
+
+*   Removed deprecated behavior that halts callbacks when the return is false.
+    ([Commit](https://github.com/rails/rails/commit/3a25cdca3e0d29ee2040931d0cb6c275d612dffe))
+
+### Deprecations
+
+*   The top level `HashWithIndifferentAccess` class has been softly deprecated
+    in favor of the `ActiveSupport::HashWithIndifferentAccess` one.
+    ([Pull Request](https://github.com/rails/rails/pull/28157))
+
+*   Deprecated passing string to `:if` and `:unless` conditional options on `set_callback` and `skip_callback`.
+    ([Commit](https://github.com/rails/rails/commit/0952552))
+
+### Notable changes
+
+*   Fixed duration parsing and traveling to make it consistent across DST changes.
+    ([Commit](https://github.com/rails/rails/commit/8931916f4a1c1d8e70c06063ba63928c5c7eab1e),
+    [Pull Request](https://github.com/rails/rails/pull/26597))
+
+*   Updated Unicode to version 9.0.0.
+    ([Pull Request](https://github.com/rails/rails/pull/27822))
+
+*   Add Duration#before and #after as aliases for #ago and #since.
+    ([Pull Request](https://github.com/rails/rails/pull/27721))
+
+*   Added `Module#delegate_missing_to` to delegate method calls not
+    defined for the current object to a proxy object.
+    ([Pull Request](https://github.com/rails/rails/pull/23930))
+
+*   Added `Date#all_day` which returns a range representing the whole day
+    of the current date & time.
+    ([Pull Request](https://github.com/rails/rails/pull/24930))
+
+*   Introduced the `assert_changes` and `assert_no_changes` methods for tests.
+    ([Pull Request](https://github.com/rails/rails/pull/25393))
+
+*   The `travel` and `travel_to` methods now raise on nested calls.
+    ([Pull Request](https://github.com/rails/rails/pull/24890))
+
+*   Update `DateTime#change` to support usec and nsec.
+    ([Pull Request](https://github.com/rails/rails/pull/28242))
+
+Credits
+-------
+
+See the
+[full list of contributors to Rails](http://contributors.rubyonrails.org/) for
+the many people who spent many hours making Rails, the stable and robust
+framework it is. Kudos to all of them.
+
+[railties]:       https://github.com/rails/rails/blob/5-1-stable/railties/CHANGELOG.md
+[action-pack]:    https://github.com/rails/rails/blob/5-1-stable/actionpack/CHANGELOG.md
+[action-view]:    https://github.com/rails/rails/blob/5-1-stable/actionview/CHANGELOG.md
+[action-mailer]:  https://github.com/rails/rails/blob/5-1-stable/actionmailer/CHANGELOG.md
+[action-cable]:   https://github.com/rails/rails/blob/5-1-stable/actioncable/CHANGELOG.md
+[active-record]:  https://github.com/rails/rails/blob/5-1-stable/activerecord/CHANGELOG.md
+[active-model]:   https://github.com/rails/rails/blob/5-1-stable/activemodel/CHANGELOG.md
+[active-support]: https://github.com/rails/rails/blob/5-1-stable/activesupport/CHANGELOG.md
+[active-job]:     https://github.com/rails/rails/blob/5-1-stable/activejob/CHANGELOG.md
diff --git a/guides/source/5_2_release_notes.md b/guides/source/5_2_release_notes.md
new file mode 100644
index 0000000000..7481d8df08
--- /dev/null
+++ b/guides/source/5_2_release_notes.md
@@ -0,0 +1,211 @@
+**DO NOT READ THIS FILE ON GITHUB, GUIDES ARE PUBLISHED ON http://guides.rubyonrails.org.**
+
+Ruby on Rails 5.2 Release Notes
+===============================
+
+Highlights in Rails 5.2:
+
+* Active Storage
+* Redis Cache Store
+* HTTP/2 Early hints support
+* Credentials
+* Default Content Security Policy
+
+These release notes cover only the major changes. To learn about various bug
+fixes and changes, please refer to the change logs or check out the [list of
+commits](https://github.com/rails/rails/commits/5-2-stable) in the main Rails
+repository on GitHub.
+
+--------------------------------------------------------------------------------
+
+Upgrading to Rails 5.2
+----------------------
+
+If you're upgrading an existing application, it's a great idea to have good test
+coverage before going in. You should also first upgrade to Rails 5.1 in case you
+haven't and make sure your application still runs as expected before attempting
+an update to Rails 5.2.
+
+
+Major Features
+--------------
+
+### Active Storage
+
+[README](https://github.com/rails/rails/blob/d3893ec38ec61282c2598b01a298124356d6b35a/activestorage/README.md)
+
+### Redis Cache Store
+
+[Pull Request](https://github.com/rails/rails/pull/31134)
+
+
+### HTTP/2 Early hints support
+
+[Pull Request](https://github.com/rails/rails/pull/30744)
+
+
+### Credentials
+
+[Pull Request](https://github.com/rails/rails/pull/30067)
+
+
+### Default Content Security Policy
+
+[Pull Request](https://github.com/rails/rails/pull/31162)
+
+Incompatibilities
+-----------------
+
+ToDo
+
+Railties
+--------
+
+Please refer to the [Changelog][railties] for detailed changes.
+
+### Deprecations
+
+*   Deprecate `capify!` method in generators and templates.
+    ([Pull Request](https://github.com/rails/rails/pull/29493))
+
+*   Deprecated passing the environment's name as a regular argument to the
+    `rails dbconsole` and `rails console` commands.
+    ([Pull Request](https://github.com/rails/rails/pull/29358))
+
+*   Deprecated using subclass of `Rails::Application` to start the Rails server.
+    ([Pull Request](https://github.com/rails/rails/pull/30127))
+
+*   Deprecated `after_bundle` callback in Rails plugin templates.
+    ([Pull Request](https://github.com/rails/rails/pull/29446))
+
+### Notable changes
+
+ToDo
+
+Action Cable
+-----------
+
+Please refer to the [Changelog][action-cable] for detailed changes.
+
+### Notable changes
+
+ToDo
+
+Action Pack
+-----------
+
+Please refer to the [Changelog][action-pack] for detailed changes.
+
+### Removals
+
+ToDo
+
+### Deprecations
+
+ToDo
+
+### Notable changes
+
+ToDo
+
+Action View
+-------------
+
+Please refer to the [Changelog][action-view] for detailed changes.
+
+### Removals
+
+ToDo
+
+### Deprecations
+
+ToDo
+
+### Notable changes
+
+ToDo
+
+Action Mailer
+-------------
+
+Please refer to the [Changelog][action-mailer] for detailed changes.
+
+### Notable changes
+
+ToDo
+
+Active Record
+-------------
+
+Please refer to the [Changelog][active-record] for detailed changes.
+
+ToDo
+
+### Deprecations
+
+ToDo
+
+### Notable changes
+
+ToDo
+
+Active Model
+------------
+
+Please refer to the [Changelog][active-model] for detailed changes.
+
+### Removals
+
+ToDo
+
+### Notable changes
+
+ToDo
+
+Active Support
+--------------
+
+Please refer to the [Changelog][active-support] for detailed changes.
+
+### Removals
+
+ToDo
+
+### Deprecations
+
+ToDo
+
+### Notable changes
+
+ToDo
+
+Active Job
+-----------
+
+Please refer to the [Changelog][active-job] for detailed changes.
+
+### Removals
+
+ToDo
+
+### Notable changes
+
+ToDo
+
+Credits
+-------
+
+See the
+[full list of contributors to Rails](http://contributors.rubyonrails.org/) for
+the many people who spent many hours making Rails, the stable and robust
+framework it is. Kudos to all of them.
+
+[railties]:       https://github.com/rails/rails/blob/5-2-stable/railties/CHANGELOG.md
+[action-pack]:    https://github.com/rails/rails/blob/5-2-stable/actionpack/CHANGELOG.md
+[action-view]:    https://github.com/rails/rails/blob/5-2-stable/actionview/CHANGELOG.md
+[action-mailer]:  https://github.com/rails/rails/blob/5-2-stable/actionmailer/CHANGELOG.md
+[action-cable]:   https://github.com/rails/rails/blob/5-2-stable/actioncable/CHANGELOG.md
+[active-record]:  https://github.com/rails/rails/blob/5-2-stable/activerecord/CHANGELOG.md
+[active-model]:   https://github.com/rails/rails/blob/5-2-stable/activemodel/CHANGELOG.md
+[active-support]: https://github.com/rails/rails/blob/5-2-stable/activesupport/CHANGELOG.md
+[active-job]:     https://github.com/rails/rails/blob/5-2-stable/activejob/CHANGELOG.md
diff --git a/guides/source/_welcome.html.erb b/guides/source/_welcome.html.erb
index f50bcddbe7..6959f992aa 100644
--- a/guides/source/_welcome.html.erb
+++ b/guides/source/_welcome.html.erb
@@ -1,8 +1,8 @@
-<h2>Ruby on Rails Guides (<%= @edge ? @version[0, 7] : @version %>)</h2>
+<h2>Ruby on Rails Guides (<%= @edge ? @edge[0, 7] : @version %>)</h2>
 
 <% if @edge %>
 <p>
-  These are <b>Edge Guides</b>, based on the current <a href="https://github.com/rails/rails/tree/<%= @version %>">master</a> branch.
+  These are <b>Edge Guides</b>, based on <a href="https://github.com/rails/rails/tree/<%= @edge %>">master@<%= @edge[0, 7] %></a>.
 </p>
 <p>
   If you are looking for the ones for the stable version, please check
@@ -10,12 +10,14 @@
 </p>
 <% else %>
 <p>
-  These are the new guides for Rails 5.0 based on <a href="https://github.com/rails/rails/tree/<%= @version %>"><%= @version %></a>.
+  These are the new guides for Rails 5.1 based on <a href="https://github.com/rails/rails/tree/<%= @version %>"><%= @version %></a>.
   These guides are designed to make you immediately productive with Rails, and to help you understand how all of the pieces fit together.
 </p>
 <% end %>
 <p>
 The guides for earlier releases:
+<a href="http://guides.rubyonrails.org/v5.1/">Rails 5.1</a>,
+<a href="http://guides.rubyonrails.org/v5.0/">Rails 5.0</a>,
 <a href="http://guides.rubyonrails.org/v4.2/">Rails 4.2</a>,
 <a href="http://guides.rubyonrails.org/v4.1/">Rails 4.1</a>,
 <a href="http://guides.rubyonrails.org/v4.0/">Rails 4.0</a>,
diff --git a/guides/source/action_cable_overview.md b/guides/source/action_cable_overview.md
index 16aa9438a2..c250db2e0c 100644
--- a/guides/source/action_cable_overview.md
+++ b/guides/source/action_cable_overview.md
@@ -1,13 +1,19 @@
+**DO NOT READ THIS FILE ON GITHUB, GUIDES ARE PUBLISHED ON http://guides.rubyonrails.org.**
+
 Action Cable Overview
 =====================
 
-In this guide you will learn how Action Cable works and how to use WebSockets to
+In this guide, you will learn how Action Cable works and how to use WebSockets to
 incorporate real-time features into your Rails application.
 
 After reading this guide, you will know:
 
+* What Action Cable is and its integration backend and frontend
 * How to setup Action Cable
 * How to setup channels
+* Deployment and Architecture setup for running Action Cable
+
+--------------------------------------------------------------------------------
 
 Introduction
 ------------
@@ -58,10 +64,10 @@ module ApplicationCable
       self.current_user = find_verified_user
     end
 
-    protected
+    private
       def find_verified_user
-        if current_user = User.find_by(id: cookies.signed[:user_id])
-          current_user
+        if verified_user = User.find_by(id: cookies.encrypted[:user_id])
+          verified_user
         else
           reject_unauthorized_connection
         end
@@ -125,7 +131,7 @@ subscriptions based on an identifier sent by the cable consumer.
 # app/channels/chat_channel.rb
 class ChatChannel < ApplicationCable::Channel
   # Called when the consumer has successfully
-  # become a subscriber of this channel.
+  # become a subscriber to this channel.
   def subscribed
   end
 end
@@ -221,7 +227,7 @@ A *broadcasting* is a pub/sub link where anything transmitted by a publisher
 is routed directly to the channel subscribers who are streaming that named
 broadcasting. Each channel can be streaming zero or more broadcastings.
 
-Broadcastings are purely an online queue and time dependent. If a consumer is
+Broadcastings are purely an online queue and time-dependent. If a consumer is
 not streaming (subscribed to a given channel), they'll not get the broadcast
 should they connect later.
 
@@ -236,12 +242,12 @@ WebNotificationsChannel.broadcast_to(
 ```
 
 The `WebNotificationsChannel.broadcast_to` call places a message in the current
-subscription adapter (Redis by default)'s pubsub queue under a separate
-broadcasting name for each user. For a user with an ID of 1, the broadcasting
-name would be `web_notifications_1`.
+subscription adapter (by default `redis` for production and `async` for development and
+test environments)'s pubsub queue under a separate broadcasting name for each user.
+For a user with an ID of 1, the broadcasting name would be `web_notifications:1`.
 
 The channel has been instructed to stream everything that arrives at
-`web_notifications_1` directly to the client by invoking the `received`
+`web_notifications:1` directly to the client by invoking the `received`
 callback.
 
 ### Subscriptions
@@ -309,7 +315,7 @@ App.cable.subscriptions.create { channel: "ChatChannel", room: "Best Room" },
 ```ruby
 # Somewhere in your app this is called, perhaps
 # from a NewCommentJob.
-ChatChannel.broadcast_to(
+ActionCable.server.broadcast(
   "chat_#{room}",
   sent_by: 'Paul',
   body: 'This is a cool chat app.'
@@ -329,7 +335,7 @@ class ChatChannel < ApplicationCable::Channel
   end
 
   def receive(data)
-    ChatChannel.broadcast_to("chat_#{params[:room]}", data)
+    ActionCable.server.broadcast("chat_#{params[:room]}", data)
   end
 end
 ```
@@ -418,7 +424,7 @@ App.cable.subscriptions.create "AppearanceChannel",
   buttonSelector = "[data-behavior~=appear_away]"
 
   install: ->
-    $(document).on "page:change.appearance", =>
+    $(document).on "turbolinks:load.appearance", =>
       @appear()
 
     $(document).on "click.appearance", buttonSelector, =>
@@ -506,13 +512,13 @@ WebNotificationsChannel.broadcast_to(
 The `WebNotificationsChannel.broadcast_to` call places a message in the current
 subscription adapter's pubsub queue under a separate broadcasting name for each
 user. For a user with an ID of 1, the broadcasting name would be
-"web_notifications_1".
+`web_notifications:1`.
 
 The channel has been instructed to stream everything that arrives at
-"web_notifications_1" directly to the client by invoking the `received`
+`web_notifications:1` directly to the client by invoking the `received`
 callback. The data passed as argument is the hash sent as the second parameter
-to the server-side broadcast call, JSON encoded for the trip across the wire,
-and unpacked for the data argument arriving to `received`.
+to the server-side broadcast call, JSON encoded for the trip across the wire
+and unpacked for the data argument arriving as `received`.
 
 ### More Complete Examples
 
@@ -526,7 +532,7 @@ Action Cable has two required configurations: a subscription adapter and allowed
 ### Subscription Adapter
 
 By default, Action Cable looks for a configuration file in `config/cable.yml`.
-The file must specify an adapter and a URL for each Rails environment. See the
+The file must specify an adapter for each Rails environment. See the
 [Dependencies](#dependencies) section for additional information on adapters.
 
 ```yaml
@@ -539,13 +545,33 @@ test:
 production:
   adapter: redis
   url: redis://10.10.3.153:6381
+  channel_prefix: appname_production
 ```
+#### Adapter Configuration
+
+Below is a list of the subscription adapters available for end users.
+
+##### Async Adapter
+
+The async adapter is intended for development/testing and should not be used in production.
+
+##### Redis Adapter
+
+The Redis adapter requires users to provide a URL pointing to the Redis server.
+Additionally, a `channel_prefix` may be provided to avoid channel name collisions
+when using the same Redis server for multiple applications. See the [Redis PubSub documentation](https://redis.io/topics/pubsub#database-amp-scoping) for more details.
+
+##### PostgreSQL Adapter
+
+The PostgreSQL adapter uses Active Record's connection pool, and thus the
+application's `config/database.yml` database configuration, for its connection.
+This may change in the future. [#27214](https://github.com/rails/rails/issues/27214)
 
 ### Allowed Request Origins
 
 Action Cable will only accept requests from specified origins, which are
 passed to the server config as an array. The origins can be instances of
-strings or regular expressions, against which a check for match will be performed.
+strings or regular expressions, against which a check for the match will be performed.
 
 ```ruby
 config.action_cable.allowed_request_origins = ['http://rubyonrails.com', %r{http://ruby.*}]
@@ -569,11 +595,12 @@ environment configuration files.
 ### Other Configurations
 
 The other common option to configure is the log tags applied to the
-per-connection logger. Here's close to what we're using in Basecamp:
+per-connection logger. Here's an example that uses
+the user account id if available, else "no-account" while tagging:
 
 ```ruby
 config.action_cable.log_tags = [
-  -> request { request.env['bc.account_id'] || "no-account" },
+  -> request { request.env['user_account_id'] || "no-account" },
   :action_cable,
   -> request { request.uuid }
 ]
@@ -582,7 +609,7 @@ config.action_cable.log_tags = [
 For a full list of all configuration options, see the
 `ActionCable::Server::Configuration` class.
 
-Also note that your server must provide at least the same number of database
+Also, note that your server must provide at least the same number of database
 connections as you have workers. The default worker pool size is set to 4, so
 that means you have to make at least that available. You can change that in
 `config/database.yml` through the `pool` attribute.
@@ -643,8 +670,8 @@ authentication. You can see one way of doing that with Devise in this [article](
 ## Dependencies
 
 Action Cable provides a subscription adapter interface to process its
-pubsub internals. By default, asynchronous, inline, PostgreSQL, evented
-Redis, and non-evented Redis adapters are included. The default adapter
+pubsub internals. By default, asynchronous, inline, PostgreSQL, and Redis
+adapters are included. The default adapter
 in new Rails applications is the asynchronous (`async`) adapter.
 
 The Ruby side of things is built on top of [websocket-driver](https://github.com/faye/websocket-driver-ruby),
diff --git a/guides/source/action_controller_overview.md b/guides/source/action_controller_overview.md
index 58362fea58..6ecfb57db3 100644
--- a/guides/source/action_controller_overview.md
+++ b/guides/source/action_controller_overview.md
@@ -21,9 +21,9 @@ After reading this guide, you will know:
 What Does a Controller Do?
 --------------------------
 
-Action Controller is the C in MVC. After the router has determined which controller to use for a request, the controller is responsible for making sense of the request and producing the appropriate output. Luckily, Action Controller does most of the groundwork for you and uses smart conventions to make this as straightforward as possible.
+Action Controller is the C in [MVC](https://en.wikipedia.org/wiki/Model%E2%80%93view%E2%80%93controller). After the router has determined which controller to use for a request, the controller is responsible for making sense of the request, and producing the appropriate output. Luckily, Action Controller does most of the groundwork for you and uses smart conventions to make this as straightforward as possible.
 
-For most conventional [RESTful](http://en.wikipedia.org/wiki/Representational_state_transfer) applications, the controller will receive the request (this is invisible to you as the developer), fetch or save data from a model and use a view to create HTML output. If your controller needs to do things a little differently, that's not a problem, this is just the most common way for a controller to work.
+For most conventional [RESTful](https://en.wikipedia.org/wiki/Representational_state_transfer) applications, the controller will receive the request (this is invisible to you as the developer), fetch or save data from a model and use a view to create HTML output. If your controller needs to do things a little differently, that's not a problem, this is just the most common way for a controller to work.
 
 A controller can thus be thought of as a middleman between models and views. It makes the model data available to the view so it can display that data to the user, and it saves or updates user data to the model.
 
@@ -61,7 +61,7 @@ end
 
 The [Layouts & Rendering Guide](layouts_and_rendering.html) explains this in more detail.
 
-`ApplicationController` inherits from `ActionController::Base`, which defines a number of helpful methods. This guide will cover some of these, but if you're curious to see what's in there, you can see all of them in the API documentation or in the source itself.
+`ApplicationController` inherits from `ActionController::Base`, which defines a number of helpful methods. This guide will cover some of these, but if you're curious to see what's in there, you can see all of them in the [API documentation](http://api.rubyonrails.org/classes/ActionController.html) or in the source itself.
 
 Only public methods are callable as actions. It is a best practice to lower the visibility of methods (with `private` or `protected`) which are not intended to be actions, like auxiliary methods or filters.
 
@@ -258,6 +258,17 @@ scalar values, map the key to an empty array:
 params.permit(id: [])
 ```
 
+Sometimes it is not possible or convenient to declare the valid keys of
+a hash parameter or its internal structure. Just map to an empty hash:
+
+```ruby
+params.permit(preferences: {})
+```
+
+but be careful because this opens the door to arbitrary input. In this
+case, `permit` ensures values in the returned structure are permitted
+scalars and filters out anything else.
+
 To whitelist an entire hash of parameters, the `permit!` method can be
 used:
 
@@ -265,9 +276,10 @@ used:
 params.require(:log_entry).permit!
 ```
 
-This will mark the `:log_entry` parameters hash and any sub-hash of it as
-permitted. Extreme care should be taken when using `permit!`, as it
-will allow all current and future model attributes to be mass-assigned.
+This marks the `:log_entry` parameters hash and any sub-hash of it as
+permitted and does not check for permitted scalars, anything is accepted.
+Extreme care should be taken when using `permit!`, as it will allow all current
+and future model attributes to be mass-assigned.
 
 #### Nested Parameters
 
@@ -362,7 +374,7 @@ If your user sessions don't store critical data or don't need to be around for l
 
 Read more about session storage in the [Security Guide](security.html).
 
-If you need a different session storage mechanism, you can change it in the `config/initializers/session_store.rb` file:
+If you need a different session storage mechanism, you can change it in an initializer:
 
 ```ruby
 # Use the database for sessions instead of the cookie-based default,
@@ -371,7 +383,7 @@ If you need a different session storage mechanism, you can change it in the `con
 # Rails.application.config.session_store :active_record_store
 ```
 
-Rails sets up a session key (the name of the cookie) when signing the session data. These can also be changed in `config/initializers/session_store.rb`:
+Rails sets up a session key (the name of the cookie) when signing the session data. These can also be changed in an initializer:
 
 ```ruby
 # Be sure to restart your server when you modify this file.
@@ -385,34 +397,18 @@ You can also pass a `:domain` key and specify the domain name for the cookie:
 Rails.application.config.session_store :cookie_store, key: '_your_app_session', domain: ".example.com"
 ```
 
-Rails sets up (for the CookieStore) a secret key used for signing the session data. This can be changed in `config/secrets.yml`
+Rails sets up (for the CookieStore) a secret key used for signing the session data in `config/credentials.yml.enc`. This can be changed with `bin/rails credentials:edit`.
 
 ```ruby
-# Be sure to restart your server when you modify this file.
+# aws:
+#   access_key_id: 123
+#   secret_access_key: 345
 
-# Your secret key is used for verifying the integrity of signed cookies.
-# If you change this key, all old signed cookies will become invalid!
-
-# Make sure the secret is at least 30 characters and all random,
-# no regular words or you'll be exposed to dictionary attacks.
-# You can use `rails secret` to generate a secure secret key.
-
-# Make sure the secrets in this file are kept private
-# if you're sharing your code publicly.
-
-development:
-  secret_key_base: a75d...
-
-test:
-  secret_key_base: 492f...
-
-# Do not keep production secrets in the repository,
-# instead read values from the environment.
-production:
-  secret_key_base: <%= ENV["SECRET_KEY_BASE"] %>
+# Used as the base secret for all MessageVerifiers in Rails, including the one protecting cookies.
+secret_key_base: 492f...
 ```
 
-NOTE: Changing the secret when using the `CookieStore` will invalidate all existing sessions.
+NOTE: Changing the secret_key_base when using the `CookieStore` will invalidate all existing sessions.
 
 ### Accessing the Session
 
@@ -658,8 +654,8 @@ class UsersController < ApplicationController
     @users = User.all
     respond_to do |format|
       format.html # index.html.erb
-      format.xml  { render xml: @users}
-      format.json { render json: @users}
+      format.xml  { render xml: @users }
+      format.json { render json: @users }
     end
   end
 end
@@ -703,11 +699,14 @@ end
 
 Now, the `LoginsController`'s `new` and `create` actions will work as before without requiring the user to be logged in. The `:only` option is used to skip this filter only for these actions, and there is also an `:except` option which works the other way. These options can be used when adding filters too, so you can add a filter which only runs for selected actions in the first place.
 
+NOTE: Calling the same filter multiple times with different options will not work,
+since the last filter definition will overwrite the previous ones.
+
 ### After Filters and Around Filters
 
 In addition to "before" filters, you can also run filters after an action has been executed, or both before and after.
 
-"after" filters are similar to "before" filters, but because the action has already been run they have access to the response data that's about to be sent to the client. Obviously, "after" filters cannot stop the action from running.
+"after" filters are similar to "before" filters, but because the action has already been run they have access to the response data that's about to be sent to the client. Obviously, "after" filters cannot stop the action from running. Please note that "after" filters are executed only after a successful action, but not when an exception is raised in the request cycle.
 
 "around" filters are responsible for running their associated actions by yielding, similar to how Rack middlewares work.
 
@@ -785,9 +784,9 @@ The way this is done is to add a non-guessable token which is only known to your
 If you generate a form like this:
 
 ```erb
-<%= form_for @user do |f| %>
-  <%= f.text_field :username %>
-  <%= f.text_field :password %>
+<%= form_with model: @user, local: true do |form| %>
+  <%= form.text_field :username %>
+  <%= form.text_field :password %>
 <% end %>
 ```
 
@@ -1117,7 +1116,7 @@ Rails default exception handling displays a "500 Server Error" message for all e
 
 ### The Default 500 and 404 Templates
 
-By default a production application will render either a 404 or a 500 error message, in the development environment all unhandled exceptions are raised. These messages are contained in static HTML files in the `public` folder, in `404.html` and `500.html` respectively. You can customize these files to add some extra information and style, but remember that they are static HTML; i.e. you can't use ERB, SCSS, CoffeeScript, or layouts for them.
+By default a production application will render either a 404 or a 500 error message, in the development environment all unhandled exceptions are raised. These messages are contained in static HTML files in the public folder, in `404.html` and `500.html` respectively. You can customize these files to add some extra information and style, but remember that they are static HTML; i.e. you can't use ERB, SCSS, CoffeeScript, or layouts for them.
 
 ### `rescue_from`
 
@@ -1171,7 +1170,7 @@ class ClientsController < ApplicationController
 end
 ```
 
-WARNING: You shouldn't do `rescue_from Exception` or `rescue_from StandardError` unless you have a particular reason as it will cause serious side-effects (e.g. you won't be able to see exception details and tracebacks during development).
+WARNING: Using `rescue_from` with `Exception` or `StandardError` would cause serious side-effects as it prevents Rails from handling exceptions properly. As such, it is not recommended to do so unless there is a strong reason.
 
 NOTE: When running in the production environment, all
 `ActiveRecord::RecordNotFound` errors render the 404 error page. Unless you need
diff --git a/guides/source/action_mailer_basics.md b/guides/source/action_mailer_basics.md
index 7359438025..cb07781d1c 100644
--- a/guides/source/action_mailer_basics.md
+++ b/guides/source/action_mailer_basics.md
@@ -64,7 +64,7 @@ Rails. Mailers are conceptually similar to controllers, and so we get a mailer,
 a directory for views, and a test.
 
 If you didn't want to use a generator, you could create your own file inside of
-app/mailers, just make sure that it inherits from `ActionMailer::Base`:
+`app/mailers`, just make sure that it inherits from `ActionMailer::Base`:
 
 ```ruby
 class MyMailer < ActionMailer::Base
@@ -92,8 +92,8 @@ registered email address:
 class UserMailer < ApplicationMailer
   default from: 'notifications@example.com'
 
-  def welcome_email(user)
-    @user = user
+  def welcome_email
+    @user = params[:user]
     @url  = 'http://example.com/login'
     mail(to: @user.email, subject: 'Welcome to My Awesome Site')
   end
@@ -160,8 +160,8 @@ When you call the `mail` method now, Action Mailer will detect the two templates
 #### Calling the Mailer
 
 Mailers are really just another way to render a view. Instead of rendering a
-view and sending out the HTTP protocol, they are just sending it out through the
-email protocols instead. Due to this, it makes sense to just have your
+view and sending it over the HTTP protocol, they are just sending it out through
+the email protocols instead. Due to this, it makes sense to just have your
 controller tell the Mailer to send an email when a user is successfully created.
 
 Setting this up is painfully simple.
@@ -176,7 +176,7 @@ $ bin/rails db:migrate
 Now that we have a user model to play with, we will just edit the
 `app/controllers/users_controller.rb` make it instruct the `UserMailer` to deliver
 an email to the newly created user by editing the create action and inserting a
-call to `UserMailer.welcome_email` right after the user is successfully saved.
+call to `UserMailer.with(user: @user).welcome_email` right after the user is successfully saved.
 
 Action Mailer is nicely integrated with Active Job so you can send emails outside
 of the request-response cycle, so the user doesn't have to wait on it:
@@ -191,7 +191,7 @@ class UsersController < ApplicationController
     respond_to do |format|
       if @user.save
         # Tell the UserMailer to send a welcome email after save
-        UserMailer.welcome_email(@user).deliver_later
+        UserMailer.with(user: @user).welcome_email.deliver_later
 
         format.html { redirect_to(@user, notice: 'User was successfully created.') }
         format.json { render json: @user, status: :created, location: @user }
@@ -220,12 +220,17 @@ If you want to send emails right away (from a cronjob for example) just call
 class SendWeeklySummary
   def run
     User.find_each do |user|
-      UserMailer.weekly_summary(user).deliver_now
+      UserMailer.with(user: user).weekly_summary.deliver_now
     end
   end
 end
 ```
 
+Any key value pair passed to `with` just becomes the `params` for the mailer
+action. So `with(user: @user, account: @user.account)` makes `params[:user]` and
+`params[:account]` available in the mailer action. Just like controllers have
+params.
+
 The method `welcome_email` returns an `ActionMailer::MessageDelivery` object which
 can then just be told `deliver_now` or `deliver_later` to send itself out. The
 `ActionMailer::MessageDelivery` object is just a wrapper around a `Mail::Message`. If
@@ -331,7 +336,7 @@ with the addresses separated by commas.
 
 ```ruby
 class AdminMailer < ApplicationMailer
-  default to: Proc.new { Admin.pluck(:email) },
+  default to: -> { Admin.pluck(:email) },
           from: 'notification@example.com'
 
   def new_registration(user)
@@ -351,8 +356,8 @@ address when they receive the email. The trick to doing that is to format the
 email address in the format `"Full Name" <email>`.
 
 ```ruby
-def welcome_email(user)
-  @user = user
+def welcome_email
+  @user = params[:user]
   email_with_name = %("#{@user.name}" <#{@user.email}>)
   mail(to: email_with_name, subject: 'Welcome to My Awesome Site')
 end
@@ -372,8 +377,8 @@ To change the default mailer view for your action you do something like:
 class UserMailer < ApplicationMailer
   default from: 'notifications@example.com'
 
-  def welcome_email(user)
-    @user = user
+  def welcome_email
+    @user = params[:user]
     @url  = 'http://example.com/login'
     mail(to: @user.email,
          subject: 'Welcome to My Awesome Site',
@@ -394,13 +399,13 @@ templates or even render inline or text without using a template file:
 class UserMailer < ApplicationMailer
   default from: 'notifications@example.com'
 
-  def welcome_email(user)
-    @user = user
+  def welcome_email
+    @user = params[:user]
     @url  = 'http://example.com/login'
     mail(to: @user.email,
          subject: 'Welcome to My Awesome Site') do |format|
       format.html { render 'another_template' }
-      format.text { render text: 'Render text' }
+      format.text { render plain: 'Render text' }
     end
   end
 end
@@ -413,7 +418,7 @@ inside of Action Controller, so you can use all the same options, such as
 
 #### Caching mailer view
 
-You can do cache in mailer views like in application views using `cache` method.
+You can perform fragment caching in mailer views like in application views using the `cache` method.
 
 ```
 <% cache do %>
@@ -427,6 +432,9 @@ And in order to use this feature, you need to configure your application with th
   config.action_mailer.perform_caching = true
 ```
 
+Fragment caching is also supported in multipart emails.
+Read more about caching in the [Rails caching guide](caching_with_rails.html).
+
 ### Action Mailer Layouts
 
 Just like controller views, you can also have mailer layouts. The layout name
@@ -450,8 +458,8 @@ the format block to specify different layouts for different formats:
 
 ```ruby
 class UserMailer < ApplicationMailer
-  def welcome_email(user)
-    mail(to: user.email) do |format|
+  def welcome_email
+    mail(to: params[:user].email) do |format|
       format.html { render layout: 'my_layout' }
       format.text
     end
@@ -474,7 +482,7 @@ special URL that renders them. In the above example, the preview class for
 ```ruby
 class UserMailerPreview < ActionMailer::Preview
   def welcome_email
-    UserMailer.welcome_email(User.first)
+    UserMailer.with(user: User.first).welcome_email
   end
 end
 ```
@@ -525,7 +533,7 @@ By using the full URL, your links will now work in your emails.
 
 #### Generating URLs with `url_for`
 
-`url_for` generate full URL by default in templates.
+`url_for` generates a full URL by default in templates.
 
 If you did not configure the `:host` option globally make sure to pass it to
 `url_for`.
@@ -550,8 +558,9 @@ url helper.
 <%= user_url(@user, host: 'example.com') %>
 ```
 
-NOTE: non-`GET` links require [jQuery UJS](https://github.com/rails/jquery-ujs)
-and won't work in mailer templates. They will result in normal `GET` requests.
+NOTE: non-`GET` links require [rails-ujs](https://github.com/rails/rails/blob/master/actionview/app/assets/javascripts) or
+[jQuery UJS](https://github.com/rails/jquery-ujs), and won't work in mailer templates.
+They will result in normal `GET` requests.
 
 ### Adding images in Action Mailer Views
 
@@ -559,7 +568,7 @@ Unlike controllers, the mailer instance doesn't have any context about the
 incoming request so you'll need to provide the `:asset_host` parameter yourself.
 
 As the `:asset_host` usually is consistent across the application you can
-configure it globally in config/application.rb:
+configure it globally in `config/application.rb`:
 
 ```ruby
 config.action_mailer.asset_host = 'http://example.com'
@@ -574,7 +583,7 @@ Now you can display an image inside your email.
 ### Sending Multipart Emails
 
 Action Mailer will automatically send multipart emails if you have different
-templates for the same action. So, for our UserMailer example, if you have
+templates for the same action. So, for our `UserMailer` example, if you have
 `welcome_email.text.erb` and `welcome_email.html.erb` in
 `app/views/user_mailer`, Action Mailer will automatically send a multipart email
 with the HTML and text versions setup as different parts.
@@ -590,12 +599,12 @@ mailer action.
 
 ```ruby
 class UserMailer < ApplicationMailer
-  def welcome_email(user, company)
-    @user = user
+  def welcome_email
+    @user = params[:user]
     @url  = user_url(@user)
-    delivery_options = { user_name: company.smtp_user,
-                         password: company.smtp_password,
-                         address: company.smtp_host }
+    delivery_options = { user_name: params[:company].smtp_user,
+                         password: params[:company].smtp_password,
+                         address: params[:company].smtp_host }
     mail(to: @user.email,
          subject: "Please see the Terms and Conditions attached",
          delivery_method_options: delivery_options)
@@ -612,9 +621,9 @@ will default to `text/plain` otherwise.
 
 ```ruby
 class UserMailer < ApplicationMailer
-  def welcome_email(user, email_body)
-    mail(to: user.email,
-         body: email_body,
+  def welcome_email
+    mail(to: params[:user].email,
+         body: params[:email_body],
          content_type: "text/html",
          subject: "Already rendered!")
   end
@@ -673,24 +682,43 @@ Action Mailer allows for you to specify a `before_action`, `after_action` and
 * You could use a `before_action` to populate the mail object with defaults,
   delivery_method_options or insert default headers and attachments.
 
+```ruby
+class InvitationsMailer < ApplicationMailer
+  before_action { @inviter, @invitee = params[:inviter], params[:invitee] }
+  before_action { @account = params[:inviter].account }
+
+  default to:       -> { @invitee.email_address },
+          from:     -> { common_address(@inviter) },
+          reply_to: -> { @inviter.email_address_with_name }
+
+  def account_invitation
+    mail subject: "#{@inviter.name} invited you to their Basecamp (#{@account.name})"
+  end
+
+  def project_invitation
+    @project    = params[:project]
+    @summarizer = ProjectInvitationSummarizer.new(@project.bucket)
+
+    mail subject: "#{@inviter.name.familiar} added you to a project in Basecamp (#{@account.name})"
+  end
+end
+```
+
 * You could use an `after_action` to do similar setup as a `before_action` but
   using instance variables set in your mailer action.
 
 ```ruby
 class UserMailer < ApplicationMailer
+  before_action { @business, @user = params[:business], params[:user] }
+
   after_action :set_delivery_options,
                :prevent_delivery_to_guests,
                :set_business_headers
 
-  def feedback_message(business, user)
-    @business = business
-    @user = user
-    mail
+  def feedback_message
   end
 
-  def campaign_message(business, user)
-    @business = business
-    @user = user
+  def campaign_message
   end
 
   private
@@ -735,7 +763,7 @@ files (environment.rb, production.rb, etc...)
 |---------------|-------------|
 |`logger`|Generates information on the mailing run if available. Can be set to `nil` for no logging. Compatible with both Ruby's own `Logger` and `Log4r` loggers.|
 |`smtp_settings`|Allows detailed configuration for `:smtp` delivery method:<ul><li>`:address` - Allows you to use a remote mail server. Just change it from its default `"localhost"` setting.</li><li>`:port` - On the off chance that your mail server doesn't run on port 25, you can change it.</li><li>`:domain` - If you need to specify a HELO domain, you can do it here.</li><li>`:user_name` - If your mail server requires authentication, set the username in this setting.</li><li>`:password` - If your mail server requires authentication, set the password in this setting.</li><li>`:authentication` - If your mail server requires authentication, you need to specify the authentication type here. This is a symbol and one of `:plain` (will send the password in the clear), `:login` (will send password Base64 encoded) or `:cram_md5` (combines a Challenge/Response mechanism to exchange information and a cryptographic Message Digest 5 algorithm to hash important information)</li><li>`:enable_starttls_auto` - Detects if STARTTLS is enabled in your SMTP server and starts to use it. Defaults to `true`.</li><li>`:openssl_verify_mode` - When using TLS, you can set how OpenSSL checks the certificate. This is really useful if you need to validate a self-signed and/or a wildcard certificate. You can use the name of an OpenSSL verify constant ('none' or 'peer') or directly the constant (`OpenSSL::SSL::VERIFY_NONE` or `OpenSSL::SSL::VERIFY_PEER`).</li></ul>|
-|`sendmail_settings`|Allows you to override options for the `:sendmail` delivery method.<ul><li>`:location` - The location of the sendmail executable. Defaults to `/usr/sbin/sendmail`.</li><li>`:arguments` - The command line arguments to be passed to sendmail. Defaults to `-i -t`.</li></ul>|
+|`sendmail_settings`|Allows you to override options for the `:sendmail` delivery method.<ul><li>`:location` - The location of the sendmail executable. Defaults to `/usr/sbin/sendmail`.</li><li>`:arguments` - The command line arguments to be passed to sendmail. Defaults to `-i`.</li></ul>|
 |`raise_delivery_errors`|Whether or not errors should be raised if the email fails to be delivered. This only works if the external email server is configured for immediate delivery.|
 |`delivery_method`|Defines a delivery method. Possible values are:<ul><li>`:smtp` (default), can be configured by using `config.action_mailer.smtp_settings`.</li><li>`:sendmail`, can be configured by using `config.action_mailer.sendmail_settings`.</li><li>`:file`: save emails to files; can be configured by using `config.action_mailer.file_settings`.</li><li>`:test`: save emails to `ActionMailer::Base.deliveries` array.</li></ul>See [API docs](http://api.rubyonrails.org/classes/ActionMailer/Base.html) for more info.|
 |`perform_deliveries`|Determines whether deliveries are actually carried out when the `deliver` method is invoked on the Mail message. By default they are, but this can be turned off to help functional testing.|
@@ -756,7 +784,7 @@ config.action_mailer.delivery_method = :sendmail
 # Defaults to:
 # config.action_mailer.sendmail_settings = {
 #   location: '/usr/sbin/sendmail',
-#   arguments: '-i -t'
+#   arguments: '-i'
 # }
 config.action_mailer.perform_deliveries = true
 config.action_mailer.raise_delivery_errors = true
@@ -780,7 +808,8 @@ config.action_mailer.smtp_settings = {
   enable_starttls_auto: true  }
 ```
 Note: As of July 15, 2014, Google increased [its security measures](https://support.google.com/accounts/answer/6010255) and now blocks attempts from apps it deems less secure.
-You can change your gmail settings [here](https://www.google.com/settings/security/lesssecureapps) to allow the attempts or
+You can change your Gmail settings [here](https://www.google.com/settings/security/lesssecureapps) to allow the attempts. If your Gmail account has 2-factor authentication enabled,
+then you will need to set an [app password](https://myaccount.google.com/apppasswords) and use that instead of your regular password. Alternatively, you can
 use another ESP to send email by replacing 'smtp.gmail.com' above with the address of your provider.
 
 Mailer Testing
diff --git a/guides/source/action_view_overview.md b/guides/source/action_view_overview.md
index f68abbae3c..1cba5c6fb6 100644
--- a/guides/source/action_view_overview.md
+++ b/guides/source/action_view_overview.md
@@ -7,7 +7,7 @@ After reading this guide, you will know:
 
 * What Action View is and how to use it with Rails.
 * How best to use templates, partials, and layouts.
-* What helpers are provided by Action View and how to make your own.
+* What helpers are provided by Action View.
 * How to use localized views.
 
 --------------------------------------------------------------------------------
@@ -149,10 +149,10 @@ end
 
 #### Jbuilder
 [Jbuilder](https://github.com/rails/jbuilder) is a gem that's
-maintained by the Rails team and included in the default Rails Gemfile.
+maintained by the Rails team and included in the default Rails `Gemfile`.
 It's similar to Builder, but is used to generate JSON, instead of XML.
 
-If you don't have it, you can add the following to your Gemfile:
+If you don't have it, you can add the following to your `Gemfile`:
 
 ```ruby
 gem 'jbuilder'
@@ -254,12 +254,6 @@ as if we had written:
 <%= render partial: "product", locals: { product: @product } %>
 ```
 
-With the `as` option we can specify a different name for the local variable. For example, if we wanted it to be `item` instead of `product` we would do:
-
-```erb
-<%= render partial: "product", as: "item" %>
-```
-
 The `object` option can be used to directly specify which object is rendered into the partial; useful when the template's object is elsewhere (e.g. in a different instance variable or in a local variable).
 
 For example, instead of:
@@ -274,12 +268,18 @@ we would do:
 <%= render partial: "product", object: @item %>
 ```
 
-The `object` and `as` options can also be used together:
+With the `as` option we can specify a different name for the said local variable. For example, if we wanted it to be `item` instead of `product` we would do:
 
 ```erb
 <%= render partial: "product", object: @item, as: "item" %>
 ```
 
+This is equivalent to
+
+```erb
+<%= render partial: "product", locals: { item: @item } %>
+```
+
 #### Rendering Collections
 
 It is very common that a template will need to iterate over a collection and render a sub-template for each of the elements. This pattern has been implemented as a single method that accepts an array and renders a partial for each one of the elements in the array.
@@ -414,12 +414,12 @@ By default, Rails links to these assets on the current host in the public folder
 
 ```ruby
 config.action_controller.asset_host = "assets.example.com"
-image_tag("rails.png") # => <img src="http://assets.example.com/images/rails.png" alt="Rails" />
+image_tag("rails.png") # => <img src="http://assets.example.com/images/rails.png" />
 ```
 
 #### auto_discovery_link_tag
 
-Returns a link tag that browsers and feed readers can use to auto-detect an RSS or Atom feed.
+Returns a link tag that browsers and feed readers can use to auto-detect an RSS, Atom, or JSON feed.
 
 ```ruby
 auto_discovery_link_tag(:rss, "http://www.example.com/feed.rss", { title: "RSS Feed" }) # =>
@@ -453,7 +453,7 @@ image_url("edit.png") # => http://www.example.com/assets/edit.png
 Returns an HTML image tag for the source. The source can be a full path or a file that exists in your `app/assets/images` directory.
 
 ```ruby
-image_tag("icon.png") # => <img src="/assets/icon.png" alt="Icon" />
+image_tag("icon.png") # => <img src="/assets/icon.png" />
 ```
 
 #### javascript_include_tag
@@ -464,25 +464,6 @@ Returns an HTML script tag for each of the sources provided. You can pass in the
 javascript_include_tag "common" # => <script src="/assets/common.js"></script>
 ```
 
-If the application does not use the asset pipeline, to include the jQuery JavaScript library in your application, pass `:defaults` as the source. When using `:defaults`, if an `application.js` file exists in your `app/assets/javascripts` directory, it will be included as well.
-
-```ruby
-javascript_include_tag :defaults
-```
-
-You can also include all JavaScript files in the `app/assets/javascripts` directory using `:all` as the source.
-
-```ruby
-javascript_include_tag :all
-```
-
-You can also cache multiple JavaScript files into one file, which requires less HTTP connections to download and can better be compressed by gzip (leading to faster transfers). Caching will only happen if `ActionController::Base.perform_caching` is set to true (which is the case by default for the Rails production environment, but not for the development environment).
-
-```ruby
-javascript_include_tag :all, cache: true # =>
-  <script src="/javascripts/all.js"></script>
-```
-
 #### javascript_path
 
 Computes the path to a JavaScript asset in the `app/assets/javascripts` directory. If the source filename has no extension, `.js` will be appended. Full paths from the document root will be passed through. Used internally by `javascript_include_tag` to build the script path.
@@ -507,22 +488,9 @@ Returns a stylesheet link tag for the sources specified as arguments. If you don
 stylesheet_link_tag "application" # => <link href="/assets/application.css" media="screen" rel="stylesheet" />
 ```
 
-You can also include all styles in the stylesheet directory using `:all` as the source:
-
-```ruby
-stylesheet_link_tag :all
-```
-
-You can also cache multiple stylesheets into one file, which requires less HTTP connections and can better be compressed by gzip (leading to faster transfers). Caching will only happen if ActionController::Base.perform_caching is set to true (which is the case by default for the Rails production environment, but not for the development environment).
-
-```ruby
-stylesheet_link_tag :all, cache: true
-# => <link href="/assets/all.css" media="screen" rel="stylesheet" />
-```
-
 #### stylesheet_path
 
-Computes the path to a stylesheet asset in the `app/assets/stylesheets` directory. If the source filename has no extension, `.css` will be appended. Full paths from the document root will be passed through. Used internally by stylesheet_link_tag to build the stylesheet path.
+Computes the path to a stylesheet asset in the `app/assets/stylesheets` directory. If the source filename has no extension, `.css` will be appended. Full paths from the document root will be passed through. Used internally by `stylesheet_link_tag` to build the stylesheet path.
 
 ```ruby
 stylesheet_path "application" # => /assets/application.css
@@ -839,20 +807,22 @@ The core method of this helper, `form_for`, gives you the ability to create a fo
 The HTML generated for this would be:
 
 ```html
-<form action="/people/create" method="post">
-  <input id="person_first_name" name="person[first_name]" type="text" />
-  <input id="person_last_name" name="person[last_name]" type="text" />
-  <input name="commit" type="submit" value="Create" />
+<form class="new_person" id="new_person" action="/people" accept-charset="UTF-8" method="post">
+  <input name="utf8" type="hidden" value="&#x2713;" />
+  <input type="hidden" name="authenticity_token" value="lTuvBzs7ANygT0NFinXj98tfw3Emfm65wwYLbUvoWsK2pngccIQSUorM2C035M9dZswXgWTvKwFS8W5TVblpYw==" />
+  <input type="text" name="person[first_name]" id="person_first_name" />
+  <input type="text" name="person[last_name]" id="person_last_name" />
+  <input type="submit" name="commit" value="Create" data-disable-with="Create" />
 </form>
 ```
 
 The params object created when this form is submitted would look like:
 
 ```ruby
-{ "action" => "create", "controller" => "people", "person" => { "first_name" => "William", "last_name" => "Smith" } }
+{"utf8" => "✓", "authenticity_token" => "lTuvBzs7ANygT0NFinXj98tfw3Emfm65wwYLbUvoWsK2pngccIQSUorM2C035M9dZswXgWTvKwFS8W5TVblpYw==", "person" => {"first_name" => "William", "last_name" => "Smith"}, "commit" => "Create", "controller" => "people", "action" => "create"}
 ```
 
-The params hash has a nested person value, which can therefore be accessed with params[:person] in the controller.
+The params hash has a nested person value, which can therefore be accessed with `params[:person]` in the controller.
 
 #### check_box
 
@@ -1192,7 +1162,7 @@ Returns a string of option tags for pretty much any time zone in the world.
 Returns select and option tags for the given object and method, using `time_zone_options_for_select` to generate the list of option tags.
 
 ```ruby
-time_zone_select( "user", "time_zone")
+time_zone_select("user", "time_zone")
 ```
 
 #### date_field
@@ -1439,7 +1409,7 @@ Formats a number with the specified level of `precision`, which defaults to 3.
 
 ```ruby
 number_with_precision(111.2345)     # => 111.235
-number_with_precision(111.2345, 2)  # => 111.23
+number_with_precision(111.2345, precision: 2)  # => 111.23
 ```
 
 ### SanitizeHelper
@@ -1493,7 +1463,7 @@ strip_links('Blog: <a href="http://myblog.com/">Visit</a>.')
 #### strip_tags(html)
 
 Strips all HTML tags from the html, including comments.
-This uses the html-scanner tokenizer and so its HTML parsing ability is limited by that of html-scanner.
+This functionality is powered by the rails-html-sanitizer gem.
 
 ```ruby
 strip_tags("Strip <i>these</i> tags!")
diff --git a/guides/source/active_job_basics.md b/guides/source/active_job_basics.md
index c9f70dc87b..914ef2c327 100644
--- a/guides/source/active_job_basics.md
+++ b/guides/source/active_job_basics.md
@@ -34,8 +34,9 @@ Delayed Job and Resque. Picking your queuing backend becomes more of an operatio
 concern, then. And you'll be able to switch between them without having to rewrite
 your jobs.
 
-NOTE: Rails by default comes with an "immediate runner" queuing implementation.
-That means that each job that has been enqueued will run immediately.
+NOTE: Rails by default comes with an asynchronous queuing implementation that
+runs jobs with an in-process thread pool. Jobs will run asynchronously, but any
+jobs in the queue will be dropped upon restart.
 
 
 Creating a Job
@@ -109,11 +110,11 @@ That's it!
 Job Execution
 -------------
 
-For enqueuing and executing jobs in production you need to set up a queuing backend, 
+For enqueuing and executing jobs in production you need to set up a queuing backend,
 that is to say you need to decide for a 3rd-party queuing library that Rails should use.
 Rails itself only provides an in-process queuing system, which only keeps the jobs in RAM.
 If the process crashes or the machine is reset, then all outstanding jobs are lost with the
-default async back-end. This may be fine for smaller apps or non-critical jobs, but most
+default async backend. This may be fine for smaller apps or non-critical jobs, but most
 production apps will need to pick a persistent backend.
 
 ### Backends
@@ -161,6 +162,7 @@ Here is a noncomprehensive list of documentation:
 
 - [Sidekiq](https://github.com/mperham/sidekiq/wiki/Active-Job)
 - [Resque](https://github.com/resque/resque/wiki/ActiveJob)
+- [Sneakers](https://github.com/jondot/sneakers/wiki/How-To:-Rails-Background-Jobs-with-ActiveJob)
 - [Sucker Punch](https://github.com/brandonhilkert/sucker_punch#active-job)
 - [Queue Classic](https://github.com/QueueClassic/queue_classic#active-job)
 
@@ -259,40 +261,48 @@ backends you need to specify the queues to listen to.
 Callbacks
 ---------
 
-Active Job provides hooks during the life cycle of a job. Callbacks allow you to
-trigger logic during the life cycle of a job.
-
-### Available callbacks
-
-* `before_enqueue`
-* `around_enqueue`
-* `after_enqueue`
-* `before_perform`
-* `around_perform`
-* `after_perform`
-
-### Usage
+Active Job provides hooks to trigger logic during the life cycle of a job. Like
+other callbacks in Rails, you can implement the callbacks as ordinary methods
+and use a macro-style class method to register them as callbacks:
 
 ```ruby
 class GuestsCleanupJob < ApplicationJob
   queue_as :default
 
-  before_enqueue do |job|
-    # Do something with the job instance
-  end
-
-  around_perform do |job, block|
-    # Do something before perform
-    block.call
-    # Do something after perform
-  end
+  around_perform :around_cleanup
 
   def perform
     # Do something later
   end
+
+  private
+    def around_cleanup(job)
+      # Do something before perform
+      yield
+      # Do something after perform
+    end
+end
+```
+
+The macro-style class methods can also receive a block. Consider using this
+style if the code inside your block is so short that it fits in a single line.
+For example, you could send metrics for every job enqueued:
+
+```ruby
+class ApplicationJob
+  before_enqueue { |job| $statsd.increment "#{job.name.underscore}.enqueue" }
 end
 ```
 
+### Available callbacks
+
+* `before_enqueue`
+* `around_enqueue`
+* `after_enqueue`
+* `before_perform`
+* `around_perform`
+* `after_perform`
+
 
 Action Mailer
 ------------
@@ -309,6 +319,12 @@ UserMailer.welcome(@user).deliver_now
 UserMailer.welcome(@user).deliver_later
 ```
 
+NOTE: Using the asynchronous queue from a Rake task (for example, to
+send an email using `.deliver_later`) will generally not work because Rake will
+likely end, causing the in-process thread pool to be deleted, before any/all
+of the `.deliver_later` emails are processed. To avoid this problem, use
+`.deliver_now` or run a persistent queue in development.
+
 
 Internationalization
 --------------------
@@ -364,7 +380,7 @@ class GuestsCleanupJob < ApplicationJob
   queue_as :default
 
   rescue_from(ActiveRecord::RecordNotFound) do |exception|
-   # Do something with the exception
+    # Do something with the exception
   end
 
   def perform
@@ -373,6 +389,25 @@ class GuestsCleanupJob < ApplicationJob
 end
 ```
 
+### Retrying or Discarding failed jobs
+
+It's also possible to retry or discard a job if an exception is raised during execution.
+For example:
+
+```ruby
+class RemoteServiceJob < ApplicationJob
+  retry_on CustomAppException # defaults to 3s wait, 5 attempts
+
+  discard_on ActiveJob::DeserializationError
+
+  def perform(*args)
+    # Might raise CustomAppException or ActiveJob::DeserializationError
+  end
+end
+```
+
+To get more details see the API Documentation for [ActiveJob::Exceptions](http://api.rubyonrails.org/classes/ActiveJob/Exceptions/ClassMethods.html).
+
 ### Deserialization
 
 GlobalID allows serializing full Active Record objects passed to `#perform`.
diff --git a/guides/source/active_model_basics.md b/guides/source/active_model_basics.md
index e834aeadb1..ee0472621b 100644
--- a/guides/source/active_model_basics.md
+++ b/guides/source/active_model_basics.md
@@ -87,7 +87,7 @@ end
 ### Conversion
 
 If a class defines `persisted?` and `id` methods, then you can include the
-`ActiveModel::Conversion` module in that class and call the Rails conversion
+`ActiveModel::Conversion` module in that class, and call the Rails conversion
 methods on objects of that class.
 
 ```ruby
@@ -156,16 +156,17 @@ person.changed? # => false
 person.first_name = "First Name"
 person.first_name # => "First Name"
 
-# returns true if any of the attributes have unsaved changes, false otherwise.
+# returns true if any of the attributes have unsaved changes.
 person.changed? # => true
 
 # returns a list of attributes that have changed before saving.
 person.changed # => ["first_name"]
 
-# returns a hash of the attributes that have changed with their original values.
+# returns a Hash of the attributes that have changed with their original values.
 person.changed_attributes # => {"first_name"=>nil}
 
-# returns a hash of changes, with the attribute names as the keys, and the values will be an array of the old and new value for that field.
+# returns a Hash of changes, with the attribute names as the keys, and the
+# values as an array of the old and new values for that field.
 person.changes # => {"first_name"=>[nil, "First Name"]}
 ```
 
@@ -179,7 +180,7 @@ person.first_name # => "First Name"
 person.first_name_changed? # => true
 ```
 
-Track what was the previous value of the attribute.
+Track the previous value of the attribute.
 
 ```ruby
 # attr_name_was accessor
@@ -187,7 +188,7 @@ person.first_name_was # => nil
 ```
 
 Track both previous and current value of the changed attribute. Returns an array
-if changed, else returns nil.
+if changed, otherwise returns nil.
 
 ```ruby
 # attr_name_change
@@ -197,7 +198,7 @@ person.last_name_change # => nil
 
 ### Validations
 
-The `ActiveModel::Validations` module adds the ability to validate class objects
+The `ActiveModel::Validations` module adds the ability to validate objects
 like in Active Record.
 
 ```ruby
@@ -225,7 +226,7 @@ person.valid?                        # => raises ActiveModel::StrictValidationFa
 
 ### Naming
 
-`ActiveModel::Naming` adds a number of class methods which make the naming and routing
+`ActiveModel::Naming` adds a number of class methods which make naming and routing
 easier to manage. The module defines the `model_name` class method which
 will define a number of accessors using some `ActiveSupport::Inflector` methods.
 
@@ -248,7 +249,7 @@ Person.model_name.singular_route_key  # => "person"
 
 ### Model
 
-`ActiveModel::Model` adds the ability to a class to work with Action Pack and
+`ActiveModel::Model` adds the ability for a class to work with Action Pack and
 Action View right out of the box.
 
 ```ruby
@@ -293,7 +294,7 @@ objects.
 ### Serialization
 
 `ActiveModel::Serialization` provides basic serialization for your object.
-You need to declare an attributes hash which contains the attributes you want to
+You need to declare an attributes Hash which contains the attributes you want to
 serialize. Attributes must be strings, not symbols.
 
 ```ruby
@@ -308,7 +309,7 @@ class Person
 end
 ```
 
-Now you can access a serialized hash of your object using the `serializable_hash`.
+Now you can access a serialized Hash of your object using the `serializable_hash` method.
 
 ```ruby
 person = Person.new
@@ -319,13 +320,14 @@ person.serializable_hash   # => {"name"=>"Bob"}
 
 #### ActiveModel::Serializers
 
-Rails provides an `ActiveModel::Serializers::JSON` serializer.
-This module automatically include the `ActiveModel::Serialization`.
+Active Model also provides the `ActiveModel::Serializers::JSON` module
+for JSON serializing / deserializing. This module automatically includes the
+previously discussed `ActiveModel::Serialization` module.
 
 ##### ActiveModel::Serializers::JSON
 
-To use the `ActiveModel::Serializers::JSON` you only need to change from
-`ActiveModel::Serialization` to `ActiveModel::Serializers::JSON`.
+To use `ActiveModel::Serializers::JSON` you only need to change the
+module you are including from `ActiveModel::Serialization` to `ActiveModel::Serializers::JSON`.
 
 ```ruby
 class Person
@@ -339,7 +341,8 @@ class Person
 end
 ```
 
-With the `as_json` method you have a hash representing the model.
+The `as_json` method, similar to `serializable_hash`, provides a Hash representing
+the model.
 
 ```ruby
 person = Person.new
@@ -348,8 +351,8 @@ person.name = "Bob"
 person.as_json # => {"name"=>"Bob"}
 ```
 
-From a JSON string you define the attributes of the model.
-You need to have the `attributes=` method defined on your class:
+You can also define the attributes for a model from a JSON string.
+However, you need to define the `attributes=` method on your class:
 
 ```ruby
 class Person
@@ -369,7 +372,7 @@ class Person
 end
 ```
 
-Now it is possible to create an instance of person and set the attributes using `from_json`.
+Now it is possible to create an instance of `Person` and set attributes using `from_json`.
 
 ```ruby
 json = { name: 'Bob' }.to_json
@@ -389,8 +392,8 @@ class Person
 end
 ```
 
-With the `human_attribute_name` you can transform attribute names into a more
-human format. The human format is defined in your locale file.
+With the `human_attribute_name` method, you can transform attribute names into a
+more human-readable format. The human-readable format is defined in your locale file(s).
 
 * config/locales/app.pt-BR.yml
 
@@ -411,16 +414,15 @@ Person.human_attribute_name('name') # => "Nome"
 `ActiveModel::Lint::Tests` allows you to test whether an object is compliant with
 the Active Model API.
 
-* app/models/person.rb
+* `app/models/person.rb`
 
     ```ruby
     class Person
       include ActiveModel::Model
-
     end
     ```
 
-* test/models/person_test.rb
+* `test/models/person_test.rb`
 
     ```ruby
     require 'test_helper'
@@ -455,19 +457,19 @@ features out of the box.
 ### SecurePassword
 
 `ActiveModel::SecurePassword` provides a way to securely store any
-password in an encrypted form. On including this module, a
+password in an encrypted form. When you include this module, a
 `has_secure_password` class method is provided which defines
-an accessor named `password` with certain validations on it.
+a `password` accessor with certain validations on it.
 
 #### Requirements
 
 `ActiveModel::SecurePassword` depends on [`bcrypt`](https://github.com/codahale/bcrypt-ruby 'BCrypt'),
-so include this gem in your Gemfile to use `ActiveModel::SecurePassword` correctly.
+so include this gem in your `Gemfile` to use `ActiveModel::SecurePassword` correctly.
 In order to make this work, the model must have an accessor named `password_digest`.
 The `has_secure_password` will add the following validations on the `password` accessor:
 
 1. Password should be present.
-2. Password should be equal to its confirmation.
+2. Password should be equal to its confirmation (provided `password_confirmation` is passed along).
 3. The maximum length of a password is 72 (required by `bcrypt` on which ActiveModel::SecurePassword depends)
 
 #### Examples
@@ -493,6 +495,10 @@ person.valid? # => false
 person.password = person.password_confirmation = 'a' * 100
 person.valid? # => false
 
+# When only password is supplied with no password_confirmation.
+person.password = 'aditya'
+person.valid? # => true
+
 # When all validations are passed.
 person.password = person.password_confirmation = 'aditya'
 person.valid? # => true
diff --git a/guides/source/active_record_basics.md b/guides/source/active_record_basics.md
index d9e9466a33..9be9c6c7b7 100644
--- a/guides/source/active_record_basics.md
+++ b/guides/source/active_record_basics.md
@@ -20,7 +20,7 @@ After reading this guide, you will know:
 What is Active Record?
 ----------------------
 
-Active Record is the M in [MVC](http://en.wikipedia.org/wiki/Model%E2%80%93view%E2%80%93controller) - the
+Active Record is the M in [MVC](https://en.wikipedia.org/wiki/Model%E2%80%93view%E2%80%93controller) - the
 model - which is the layer of the system responsible for representing business
 data and logic. Active Record facilitates the creation and use of business
 objects whose data requires persistent storage to a database. It is an
@@ -38,7 +38,7 @@ object on how to write to and read from the database.
 
 ### Object Relational Mapping
 
-Object Relational Mapping, commonly referred to as its abbreviation ORM, is
+[Object Relational Mapping](https://en.wikipedia.org/wiki/Object-relational_mapping), commonly referred to as its abbreviation ORM, is
 a technique that connects the rich objects of an application to tables in
 a relational database management system. Using ORM, the properties and
 relationships of the objects in an application can be easily stored and
@@ -104,7 +104,7 @@ depending on the purpose of these columns.
   your models.
 * **Primary keys** - By default, Active Record will use an integer column named
   `id` as the table's primary key. When using [Active Record
-  Migrations](migrations.html) to create your tables, this column will be
+  Migrations](active_record_migrations.html) to create your tables, this column will be
   automatically created.
 
 There are also some optional column names that will add additional features
@@ -304,6 +304,17 @@ user = User.find_by(name: 'David')
 user.destroy
 ```
 
+If you'd like to delete several records in bulk, you may use `destroy_all`
+method:
+
+```ruby
+# find and delete all users named David
+User.where(name: 'David').destroy_all
+
+# delete all users
+User.destroy_all
+```
+
 Validations
 -----------
 
@@ -314,8 +325,8 @@ already in the database, follows a specific format and many more.
 
 Validation is a very important issue to consider when persisting to the database, so
 the methods `save` and `update` take it into account when
-running: they return `false` when validation fails and they didn't actually
-perform any operation on the database. All of these have a bang counterpart (that
+running: they return `false` when validation fails and they don't actually
+perform any operations on the database. All of these have a bang counterpart (that
 is, `save!` and `update!`), which are stricter in that
 they raise the exception `ActiveRecord::RecordInvalid` if validation fails.
 A quick example to illustrate:
@@ -374,4 +385,4 @@ and to roll it back, `rails db:rollback`.
 
 Note that the above code is database-agnostic: it will run in MySQL,
 PostgreSQL, Oracle and others. You can learn more about migrations in the
-[Active Record Migrations guide](migrations.html).
+[Active Record Migrations guide](active_record_migrations.html).
diff --git a/guides/source/active_record_callbacks.md b/guides/source/active_record_callbacks.md
index a7975c7772..630dafe632 100644
--- a/guides/source/active_record_callbacks.md
+++ b/guides/source/active_record_callbacks.md
@@ -36,7 +36,7 @@ class User < ApplicationRecord
 
   before_validation :ensure_login_has_a_value
 
-  protected
+  private
     def ensure_login_has_a_value
       if login.nil?
         self.login = email unless email.blank?
@@ -66,7 +66,7 @@ class User < ApplicationRecord
   # :on takes an array as well
   after_validation :set_location, on: [ :create, :update ]
 
-  protected
+  private
     def normalize_name
       self.name = name.downcase.titleize
     end
@@ -77,7 +77,7 @@ class User < ApplicationRecord
 end
 ```
 
-It is considered good practice to declare callback methods as protected or private. If left public, they can be called from outside of the model and violate the principle of object encapsulation.
+It is considered good practice to declare callback methods as private. If left public, they can be called from outside of the model and violate the principle of object encapsulation.
 
 Available Callbacks
 -------------------
@@ -117,6 +117,10 @@ Here is a list with all the available Active Record callbacks, listed in the sam
 
 WARNING. `after_save` runs both on create and update, but always _after_ the more specific callbacks `after_create` and `after_update`, no matter the order in which the macro calls were executed.
 
+NOTE: `before_destroy` callbacks should be placed before `dependent: :destroy`
+associations (or use the `prepend: true` option), to ensure they execute before
+the records are deleted by `dependent: :destroy`.
+
 ### `after_initialize` and `after_find`
 
 The `after_initialize` callback will be called whenever an Active Record object is instantiated, either by directly using `new` or when a record is loaded from the database. It can be useful to avoid the need to directly override your Active Record `initialize` method.
@@ -202,15 +206,14 @@ The following methods trigger callbacks:
 
 * `create`
 * `create!`
-* `decrement!`
 * `destroy`
 * `destroy!`
 * `destroy_all`
-* `increment!`
 * `save`
 * `save!`
 * `save(validate: false)`
 * `toggle!`
+* `touch`
 * `update_attribute`
 * `update`
 * `update!`
@@ -243,7 +246,6 @@ Just as with validations, it is also possible to skip callbacks by using the fol
 * `increment`
 * `increment_counter`
 * `toggle`
-* `touch`
 * `update_column`
 * `update_columns`
 * `update_all`
@@ -256,7 +258,11 @@ Halting Execution
 
 As you start registering new callbacks for your models, they will be queued for execution. This queue will include all your model's validations, the registered callbacks, and the database operation to be executed.
 
-The whole callback chain is wrapped in a transaction. If any _before_ callback method returns exactly `false` or raises an exception, the execution chain gets halted and a ROLLBACK is issued; _after_ callbacks can only accomplish that by raising an exception.
+The whole callback chain is wrapped in a transaction. If any callback raises an exception, the execution chain gets halted and a ROLLBACK is issued. To intentionally stop a chain use:
+
+```ruby
+throw :abort
+```
 
 WARNING. Any exception that is not `ActiveRecord::Rollback` or `ActiveRecord::RecordInvalid` will be re-raised by Rails after the callback chain is halted. Raising an exception other than `ActiveRecord::Rollback` or `ActiveRecord::RecordInvalid` may break code that does not expect methods like `save` and `update_attributes` (which normally try to return `true` or `false`) to raise an exception.
 
@@ -290,7 +296,7 @@ Article destroyed
 Conditional Callbacks
 ---------------------
 
-As with validations, we can also make the calling of a callback method conditional on the satisfaction of a given predicate. We can do this using the `:if` and `:unless` options, which can take a symbol, a string, a `Proc` or an `Array`. You may use the `:if` option when you want to specify under which conditions the callback **should** be called. If you want to specify the conditions under which the callback **should not** be called, then you may use the `:unless` option.
+As with validations, we can also make the calling of a callback method conditional on the satisfaction of a given predicate. We can do this using the `:if` and `:unless` options, which can take a symbol, a `Proc` or an `Array`. You may use the `:if` option when you want to specify under which conditions the callback **should** be called. If you want to specify the conditions under which the callback **should not** be called, then you may use the `:unless` option.
 
 ### Using `:if` and `:unless` with a `Symbol`
 
@@ -302,16 +308,6 @@ class Order < ApplicationRecord
 end
 ```
 
-### Using `:if` and `:unless` with a String
-
-You can also use a string that will be evaluated using `eval` and hence needs to contain valid Ruby code. You should use this option only when the string represents a really short condition:
-
-```ruby
-class Order < ApplicationRecord
-  before_save :normalize_card_number, if: "paid_with_card?"
-end
-```
-
 ### Using `:if` and `:unless` with a `Proc`
 
 Finally, it is possible to associate `:if` and `:unless` with a `Proc` object. This option is best suited when writing short validation methods, usually one-liners:
@@ -431,4 +427,33 @@ class PictureFile < ApplicationRecord
 end
 ```
 
-WARNING. The `after_commit` and `after_rollback` callbacks are guaranteed to be called for all models created, updated, or destroyed within a transaction block. If any exceptions are raised within one of these callbacks, they will be ignored so that they don't interfere with the other callbacks. As such, if your callback code could raise an exception, you'll need to rescue it and handle it appropriately within the callback.
+WARNING. The `after_commit` and `after_rollback` callbacks are called for all models created, updated, or destroyed within a transaction block. However, if an exception is raised within one of these callbacks, the exception will bubble up and any remaining `after_commit` or `after_rollback` methods will _not_ be executed. As such, if your callback code could raise an exception, you'll need to rescue it and handle it within the callback in order to allow other callbacks to run.
+
+WARNING. Using both `after_create_commit` and `after_update_commit` in the same model will only allow the last callback defined to take effect, and will override all others.
+
+```ruby
+class User < ApplicationRecord
+  after_create_commit :log_user_saved_to_db
+  after_update_commit :log_user_saved_to_db
+
+  private
+  def log_user_saved_to_db
+    puts 'User was saved to database'
+  end
+end
+
+# prints nothing
+>> @user = User.create
+
+# updating @user
+>> @user.save
+=> User was saved to database
+```
+
+To register callbacks for both create and update actions, use `after_commit` instead.
+
+```ruby
+class User < ApplicationRecord
+  after_commit :log_user_saved_to_db, on: [:create, :update]
+end
+```
diff --git a/guides/source/active_record_migrations.md b/guides/source/active_record_migrations.md
index f914122242..ab3af438f5 100644
--- a/guides/source/active_record_migrations.md
+++ b/guides/source/active_record_migrations.md
@@ -21,7 +21,7 @@ Migration Overview
 ------------------
 
 Migrations are a convenient way to
-[alter your database schema over time](http://en.wikipedia.org/wiki/Schema_migration)
+[alter your database schema over time](https://en.wikipedia.org/wiki/Schema_migration)
 in a consistent and easy way. They use a Ruby DSL so that you don't have to
 write SQL by hand, allowing your schema and changes to be database independent.
 
@@ -229,7 +229,7 @@ As always, what has been generated for you is just a starting point. You can add
 or remove from it as you see fit by editing the
 `db/migrate/YYYYMMDDHHMMSS_add_details_to_products.rb` file.
 
-Also, the generator accepts column type as `references`(also available as
+Also, the generator accepts column type as `references` (also available as
 `belongs_to`). For instance:
 
 ```bash
@@ -241,7 +241,7 @@ generates
 ```ruby
 class AddUserRefToProducts < ActiveRecord::Migration[5.0]
   def change
-    add_reference :products, :user, index: true, foreign_key: true
+    add_reference :products, :user, foreign_key: true
   end
 end
 ```
@@ -313,7 +313,7 @@ will produce a migration that looks like this
 class AddDetailsToProducts < ActiveRecord::Migration[5.0]
   def change
     add_column :products, :price, :decimal, precision: 5, scale: 2
-    add_reference :products, :supplier, polymorphic: true, index: true
+    add_reference :products, :supplier, polymorphic: true
   end
 end
 ```
@@ -353,8 +353,7 @@ create_table :products, options: "ENGINE=BLACKHOLE" do |t|
 end
 ```
 
-will append `ENGINE=BLACKHOLE` to the SQL statement used to create the table
-(when using MySQL or MariaDB, the default is `ENGINE=InnoDB`).
+will append `ENGINE=BLACKHOLE` to the SQL statement used to create the table.
 
 Also you can pass the `:comment` option with any description for the table
 that will be stored in database itself and can be viewed with database administration
@@ -467,6 +466,8 @@ the first time (i.e. on the date the migration is applied).
 Some adapters may support additional options; see the adapter specific API docs
 for further information.
 
+NOTE: `null` and `default` cannot be specified via command line.
+
 ### Foreign Keys
 
 While it's not required you might want to add foreign key constraints to
@@ -956,10 +957,10 @@ ActiveRecord::Schema.define(version: 20080906171750) do
 
   create_table "products", force: true do |t|
     t.string   "name"
-    t.text "description"
+    t.text     "description"
     t.datetime "created_at"
     t.datetime "updated_at"
-    t.string "part_number"
+    t.string   "part_number"
   end
 end
 ```
@@ -970,11 +971,11 @@ on. Because this is database-independent, it could be loaded into any database
 that Active Record supports. This could be very useful if you were to
 distribute an application that is able to run against multiple databases.
 
-There is however a trade-off: `db/schema.rb` cannot express database specific
-items such as triggers, stored procedures or check constraints. While in a
-migration you can execute custom SQL statements, the schema dumper cannot
-reconstitute those statements from the database. If you are using features like
-this, then you should set the schema format to `:sql`.
+NOTE: `db/schema.rb` cannot express database specific items such as triggers,
+sequences, stored procedures or check constraints, etc. Please note that while
+custom SQL statements can be run in migrations, these statements cannot be reconstituted
+by the schema dumper. If you are using features like this, then you
+should set the schema format to `:sql`.
 
 Instead of using Active Record's schema dumper, the database's structure will
 be dumped using a tool specific to the database (via the `db:structure:dump`
@@ -1018,10 +1019,10 @@ such features, the `execute` method can be used to execute arbitrary SQL.
 Migrations and Seed Data
 ------------------------
 
-The main purpose of Rails' migration feature is to issue commands that modify the 
-schema using a consistent process. Migrations can also be used 
-to add or modify data. This is useful in an existing database that can't be destroyed 
-and recreated, such as a production database. 
+The main purpose of Rails' migration feature is to issue commands that modify the
+schema using a consistent process. Migrations can also be used
+to add or modify data. This is useful in an existing database that can't be destroyed
+and recreated, such as a production database.
 
 ```ruby
 class AddInitialProducts < ActiveRecord::Migration[5.0]
@@ -1037,10 +1038,10 @@ class AddInitialProducts < ActiveRecord::Migration[5.0]
 end
 ```
 
-To add initial data after a database is created, Rails has a built-in 
-'seeds' feature that makes the process quick and easy. This is especially 
-useful when reloading the database frequently in development and test environments. 
-It's easy to get started with this feature: just fill up `db/seeds.rb` with some 
+To add initial data after a database is created, Rails has a built-in
+'seeds' feature that makes the process quick and easy. This is especially
+useful when reloading the database frequently in development and test environments.
+It's easy to get started with this feature: just fill up `db/seeds.rb` with some
 Ruby code, and run `rails db:seed`:
 
 ```ruby
diff --git a/guides/source/active_record_postgresql.md b/guides/source/active_record_postgresql.md
index d7e35490ef..58c61f0864 100644
--- a/guides/source/active_record_postgresql.md
+++ b/guides/source/active_record_postgresql.md
@@ -29,8 +29,8 @@ that are supported by the PostgreSQL adapter.
 
 ### Bytea
 
-* [type definition](http://www.postgresql.org/docs/current/static/datatype-binary.html)
-* [functions and operators](http://www.postgresql.org/docs/current/static/functions-binarystring.html)
+* [type definition](https://www.postgresql.org/docs/current/static/datatype-binary.html)
+* [functions and operators](https://www.postgresql.org/docs/current/static/functions-binarystring.html)
 
 ```ruby
 # db/migrate/20140207133952_create_documents.rb
@@ -49,8 +49,8 @@ Document.create payload: data
 
 ### Array
 
-* [type definition](http://www.postgresql.org/docs/current/static/arrays.html)
-* [functions and operators](http://www.postgresql.org/docs/current/static/functions-array.html)
+* [type definition](https://www.postgresql.org/docs/current/static/arrays.html)
+* [functions and operators](https://www.postgresql.org/docs/current/static/functions-array.html)
 
 ```ruby
 # db/migrate/20140207133952_create_books.rb
@@ -83,8 +83,8 @@ Book.where("array_length(ratings, 1) >= 3")
 
 ### Hstore
 
-* [type definition](http://www.postgresql.org/docs/current/static/hstore.html)
-* [functions and operators](http://www.postgresql.org/docs/current/static/hstore.html#AEN167712)
+* [type definition](https://www.postgresql.org/docs/current/static/hstore.html)
+* [functions and operators](https://www.postgresql.org/docs/current/static/hstore.html#AEN179902)
 
 NOTE: You need to enable the `hstore` extension to use hstore.
 
@@ -111,19 +111,24 @@ profile.settings = {"color" => "yellow", "resolution" => "1280x1024"}
 profile.save!
 
 Profile.where("settings->'color' = ?", "yellow")
-#=> #<ActiveRecord::Relation [#<Profile id: 1, settings: {"color"=>"yellow", "resolution"=>"1280x1024"}>]>
+# => #<ActiveRecord::Relation [#<Profile id: 1, settings: {"color"=>"yellow", "resolution"=>"1280x1024"}>]>
 ```
 
-### JSON
+### JSON and JSONB
 
-* [type definition](http://www.postgresql.org/docs/current/static/datatype-json.html)
-* [functions and operators](http://www.postgresql.org/docs/current/static/functions-json.html)
+* [type definition](https://www.postgresql.org/docs/current/static/datatype-json.html)
+* [functions and operators](https://www.postgresql.org/docs/current/static/functions-json.html)
 
 ```ruby
 # db/migrate/20131220144913_create_events.rb
+# ... for json datatype:
 create_table :events do |t|
   t.json 'payload'
 end
+# ... or for jsonb datatype:
+create_table :events do |t|
+  t.jsonb 'payload'
+end
 
 # app/models/event.rb
 class Event < ApplicationRecord
@@ -142,8 +147,8 @@ Event.where("payload->>'kind' = ?", "user_renamed")
 
 ### Range Types
 
-* [type definition](http://www.postgresql.org/docs/current/static/rangetypes.html)
-* [functions and operators](http://www.postgresql.org/docs/current/static/functions-range.html)
+* [type definition](https://www.postgresql.org/docs/current/static/rangetypes.html)
+* [functions and operators](https://www.postgresql.org/docs/current/static/functions-range.html)
 
 This type is mapped to Ruby [`Range`](http://www.ruby-doc.org/core-2.2.2/Range.html) objects.
 
@@ -177,7 +182,7 @@ event.ends_at # => Thu, 13 Feb 2014
 
 ### Composite Types
 
-* [type definition](http://www.postgresql.org/docs/current/static/rowtypes.html)
+* [type definition](https://www.postgresql.org/docs/current/static/rowtypes.html)
 
 Currently there is no special support for composite types. They are mapped to
 normal text columns:
@@ -217,7 +222,7 @@ contact.save!
 
 ### Enumerated Types
 
-* [type definition](http://www.postgresql.org/docs/current/static/datatype-enum.html)
+* [type definition](https://www.postgresql.org/docs/current/static/datatype-enum.html)
 
 Currently there is no special support for enumerated types. They are mapped as
 normal text columns:
@@ -255,7 +260,7 @@ article.status = "published"
 article.save!
 ```
 
-To add a new value before/after existing one you should use [ALTER TYPE](http://www.postgresql.org/docs/current/static/sql-altertype.html):
+To add a new value before/after existing one you should use [ALTER TYPE](https://www.postgresql.org/docs/current/static/sql-altertype.html):
 
 ```ruby
 # db/migrate/20150720144913_add_new_state_to_articles.rb
@@ -269,7 +274,7 @@ def up
 end
 ```
 
-NOTE: ENUM values can't be dropped currently. You can read why [here](http://www.postgresql.org/message-id/29F36C7C98AB09499B1A209D48EAA615B7653DBC8A@mail2a.alliedtesting.com).
+NOTE: ENUM values can't be dropped currently. You can read why [here](https://www.postgresql.org/message-id/29F36C7C98AB09499B1A209D48EAA615B7653DBC8A@mail2a.alliedtesting.com).
 
 Hint: to show all the values of the all enums you have, you should call this query in `bin/rails db` or `psql` console:
 
@@ -284,9 +289,9 @@ SELECT n.nspname AS enum_schema,
 
 ### UUID
 
-* [type definition](http://www.postgresql.org/docs/current/static/datatype-uuid.html)
-* [pgcrypto generator function](http://www.postgresql.org/docs/current/static/pgcrypto.html#AEN159361)
-* [uuid-ossp generator functions](http://www.postgresql.org/docs/current/static/uuid-ossp.html)
+* [type definition](https://www.postgresql.org/docs/current/static/datatype-uuid.html)
+* [pgcrypto generator function](https://www.postgresql.org/docs/current/static/pgcrypto.html#AEN182570)
+* [uuid-ossp generator functions](https://www.postgresql.org/docs/current/static/uuid-ossp.html)
 
 NOTE: You need to enable the `pgcrypto` (only PostgreSQL >= 9.4) or `uuid-ossp`
 extension to use uuid.
@@ -335,8 +340,8 @@ See [this section](#uuid-primary-keys) for more details on using UUIDs as primar
 
 ### Bit String Types
 
-* [type definition](http://www.postgresql.org/docs/current/static/datatype-bit.html)
-* [functions and operators](http://www.postgresql.org/docs/current/static/functions-bitstring.html)
+* [type definition](https://www.postgresql.org/docs/current/static/datatype-bit.html)
+* [functions and operators](https://www.postgresql.org/docs/current/static/functions-bitstring.html)
 
 ```ruby
 # db/migrate/20131220144913_create_users.rb
@@ -359,7 +364,7 @@ user.save!
 
 ### Network Address Types
 
-* [type definition](http://www.postgresql.org/docs/current/static/datatype-net-types.html)
+* [type definition](https://www.postgresql.org/docs/current/static/datatype-net-types.html)
 
 The types `inet` and `cidr` are mapped to Ruby
 [`IPAddr`](http://www.ruby-doc.org/stdlib-2.2.2/libdoc/ipaddr/rdoc/IPAddr.html)
@@ -394,7 +399,7 @@ macbook.address
 
 ### Geometric Types
 
-* [type definition](http://www.postgresql.org/docs/current/static/datatype-geometric.html)
+* [type definition](https://www.postgresql.org/docs/current/static/datatype-geometric.html)
 
 All geometric types, with the exception of `points` are mapped to normal text.
 A point is casted to an array containing `x` and `y` coordinates.
@@ -422,7 +427,7 @@ device = Device.create
 device.id # => "814865cd-5a1d-4771-9306-4268f188fe9e"
 ```
 
-NOTE: `uuid_generate_v4()` (from `uuid-ossp`) is assumed if no `:default` option was
+NOTE: `gen_random_uuid()` (from `pgcrypto`) is assumed if no `:default` option was
 passed to `create_table`.
 
 Full Text Search
@@ -452,7 +457,7 @@ Document.where("to_tsvector('english', title || ' ' || body) @@ to_tsquery(?)",
 Database Views
 --------------
 
-* [view creation](http://www.postgresql.org/docs/current/static/sql-createview.html)
+* [view creation](https://www.postgresql.org/docs/current/static/sql-createview.html)
 
 Imagine you need to work with a legacy database containing the following table:
 
diff --git a/guides/source/active_record_querying.md b/guides/source/active_record_querying.md
index 928ab43b3b..4e28e31a53 100644
--- a/guides/source/active_record_querying.md
+++ b/guides/source/active_record_querying.md
@@ -50,7 +50,7 @@ class Role < ApplicationRecord
 end
 ```
 
-Active Record will perform queries on the database for you and is compatible with most database systems, including MySQL, MariaDB, PostgreSQL and SQLite. Regardless of which database system you're using, the Active Record method format will always be the same.
+Active Record will perform queries on the database for you and is compatible with most database systems, including MySQL, MariaDB, PostgreSQL, and SQLite. Regardless of which database system you're using, the Active Record method format will always be the same.
 
 Retrieving Objects from the Database
 ------------------------------------
@@ -81,10 +81,9 @@ The methods are:
 * `reorder`
 * `reverse_order`
 * `select`
-* `distinct`
 * `where`
 
-All of the above methods return an instance of `ActiveRecord::Relation`.
+Finder methods that return a collection, such as `where` and `group`, return an instance of `ActiveRecord::Relation`.  Methods that find a single entity, such as `find` and `first`, return a single instance of the model.
 
 The primary operation of `Model.find(options)` can be summarized as:
 
@@ -119,7 +118,7 @@ You can also use this method to query for multiple objects. Call the `find` meth
 
 ```ruby
 # Find the clients with primary keys 1 and 10.
-client = Client.find([1, 10]) # Or even Client.find(1, 10)
+clients = Client.find([1, 10]) # Or even Client.find(1, 10)
 # => [#<Client id: 1, first_name: "Lifo">, #<Client id: 10, first_name: "Ryan">]
 ```
 
@@ -151,7 +150,7 @@ The `take` method returns `nil` if no record is found and no exception will be r
 You can pass in a numerical argument to the `take` method to return up to that number of results. For example
 
 ```ruby
-client = Client.take(2)
+clients = Client.take(2)
 # => [
 #   #<Client id: 1, first_name: "Lifo">,
 #   #<Client id: 220, first_name: "Sara">
@@ -190,7 +189,7 @@ If your [default scope](active_record_querying.html#applying-a-default-scope) co
 You can pass in a numerical argument to the `first` method to return up to that number of results. For example
 
 ```ruby
-client = Client.first(3)
+clients = Client.first(3)
 # => [
 #   #<Client id: 1, first_name: "Lifo">,
 #   #<Client id: 2, first_name: "Fifo">,
@@ -204,7 +203,7 @@ The SQL equivalent of the above is:
 SELECT * FROM clients ORDER BY clients.id ASC LIMIT 3
 ```
 
-On a collection that is ordered using `order`, `first` will return the first record ordered by the specified attribute for `order`. 
+On a collection that is ordered using `order`, `first` will return the first record ordered by the specified attribute for `order`.
 
 ```ruby
 client = Client.order(:first_name).first
@@ -241,7 +240,7 @@ If your [default scope](active_record_querying.html#applying-a-default-scope) co
 You can pass in a numerical argument to the `last` method to return up to that number of results. For example
 
 ```ruby
-client = Client.last(3)
+clients = Client.last(3)
 # => [
 #   #<Client id: 219, first_name: "James">,
 #   #<Client id: 220, first_name: "Sara">,
@@ -255,7 +254,7 @@ The SQL equivalent of the above is:
 SELECT * FROM clients ORDER BY clients.id DESC LIMIT 3
 ```
 
-On a collection that is ordered using `order`, `last` will return the last record ordered by the specified attribute for `order`. 
+On a collection that is ordered using `order`, `last` will return the last record ordered by the specified attribute for `order`.
 
 ```ruby
 client = Client.order(:first_name).last
@@ -314,7 +313,7 @@ We often need to iterate over a large set of records, as when we send a newslett
 This may appear straightforward:
 
 ```ruby
-# This is very inefficient when the users table has thousands of rows.
+# This may consume too much memory if the table is big.
 User.all.each do |user|
   NewsMailer.weekly(user).deliver_now
 end
@@ -328,7 +327,7 @@ TIP: The `find_each` and `find_in_batches` methods are intended for use in the b
 
 #### `find_each`
 
-The `find_each` method retrieves a batch of records and then yields _each_ record to the block individually as a model. In the following example, `find_each` will retrieve 1000 records (the current default for both `find_each` and `find_in_batches`) and then yield each record individually to the block as a model. This process is repeated until all of the records have been processed:
+The `find_each` method retrieves records in batches and then yields _each_ one to the block. In the following example, `find_each` retrieves users in batches of 1000 and yields them to the block one by one:
 
 ```ruby
 User.find_each do |user|
@@ -336,7 +335,9 @@ User.find_each do |user|
 end
 ```
 
-To add conditions to a `find_each` operation you can chain other Active Record methods such as `where`:
+This process is repeated, fetching more batches as needed, until all of the records have been processed.
+
+`find_each` works on model classes, as seen above, and also on relations:
 
 ```ruby
 User.where(weekly_subscriber: true).find_each do |user|
@@ -344,11 +345,16 @@ User.where(weekly_subscriber: true).find_each do |user|
 end
 ```
 
-##### Options for `find_each`
+as long as they have no ordering, since the method needs to force an order
+internally to iterate.
 
-The `find_each` method accepts most of the options allowed by the regular `find` method, except for `:order` and `:limit`, which are reserved for internal use by `find_each`.
+If an order is present in the receiver the behaviour depends on the flag
+`config.active_record.error_on_ignored_order`. If true, `ArgumentError` is
+raised, otherwise the order is ignored and a warning issued, which is the
+default. This can be overridden with the option `:error_on_ignore`, explained
+below.
 
-Three additional options, `:batch_size`, `:start` and `:finish`, are available as well.
+##### Options for `find_each`
 
 **`:batch_size`**
 
@@ -364,10 +370,10 @@ end
 
 By default, records are fetched in ascending order of the primary key, which must be an integer. The `:start` option allows you to configure the first ID of the sequence whenever the lowest ID is not the one you need. This would be useful, for example, if you wanted to resume an interrupted batch process, provided you saved the last processed ID as a checkpoint.
 
-For example, to send newsletters only to users with the primary key starting from 2000, and to retrieve them in batches of 5000:
+For example, to send newsletters only to users with the primary key starting from 2000:
 
 ```ruby
-User.find_each(start: 2000, batch_size: 5000) do |user|
+User.find_each(start: 2000) do |user|
   NewsMailer.weekly(user).deliver_now
 end
 ```
@@ -375,12 +381,12 @@ end
 **`:finish`**
 
 Similar to the `:start` option, `:finish` allows you to configure the last ID of the sequence whenever the highest ID is not the one you need.
-This would be useful, for example, if you wanted to run a batch process, using a subset of records based on `:start` and `:finish`
+This would be useful, for example, if you wanted to run a batch process using a subset of records based on `:start` and `:finish`.
 
-For example, to send newsletters only to users with the primary key starting from 2000 up to 10000 and to retrieve them in batches of 5000:
+For example, to send newsletters only to users with the primary key starting from 2000 up to 10000:
 
 ```ruby
-User.find_each(start: 2000, finish: 10000, batch_size: 5000) do |user|
+User.find_each(start: 2000, finish: 10000) do |user|
   NewsMailer.weekly(user).deliver_now
 end
 ```
@@ -389,20 +395,36 @@ Another example would be if you wanted multiple workers handling the same
 processing queue. You could have each worker handle 10000 records by setting the
 appropriate `:start` and `:finish` options on each worker.
 
+**`:error_on_ignore`**
+
+Overrides the application config to specify if an error should be raised when an
+order is present in the relation.
+
 #### `find_in_batches`
 
 The `find_in_batches` method is similar to `find_each`, since both retrieve batches of records. The difference is that `find_in_batches` yields _batches_ to the block as an array of models, instead of individually. The following example will yield to the supplied block an array of up to 1000 invoices at a time, with the final block containing any remaining invoices:
 
 ```ruby
-# Give add_invoices an array of 1000 invoices at a time
+# Give add_invoices an array of 1000 invoices at a time.
 Invoice.find_in_batches do |invoices|
   export.add_invoices(invoices)
 end
 ```
 
+`find_in_batches` works on model classes, as seen above, and also on relations:
+
+```ruby
+Invoice.pending.find_in_batches do |invoices|
+  pending_invoices_export.add_invoices(invoices)
+end
+```
+
+as long as they have no ordering, since the method needs to force an order
+internally to iterate.
+
 ##### Options for `find_in_batches`
 
-The `find_in_batches` method accepts the same `:batch_size`, `:start` and `:finish` options as `find_each`.
+The `find_in_batches` method accepts the same options as `find_each`.
 
 Conditions
 ----------
@@ -491,8 +513,6 @@ Article.where(author: author)
 Author.joins(:articles).where(articles: { author: author })
 ```
 
-NOTE: The values cannot be symbols. For example, you cannot do `Client.where(status: :active)`.
-
 #### Range Conditions
 
 ```ruby
@@ -535,6 +555,19 @@ In other words, this query can be generated by calling `where` with no argument,
 SELECT * FROM clients WHERE (clients.locked != 1)
 ```
 
+### OR Conditions
+
+`OR` conditions between two relations can be built by calling `or` on the first
+relation, and passing the second one as an argument.
+
+```ruby
+Client.where(locked: true).or(Client.where(orders_count: [1,3,5]))
+```
+
+```sql
+SELECT * FROM clients WHERE (clients.locked = 1 OR clients.orders_count IN (1,3,5))
+```
+
 Ordering
 --------
 
@@ -578,6 +611,7 @@ If you want to call `order` multiple times, subsequent orders will be appended t
 Client.order("orders_count ASC").order("created_at DESC")
 # SELECT * FROM clients ORDER BY orders_count ASC, created_at DESC
 ```
+WARNING: If you are using **MySQL 5.7.5** and above, then on selecting fields from a result set using methods like `select`, `pluck` and `ids`; the `order` method will raise an `ActiveRecord::StatementInvalid` exception unless the field(s) used in `order` clause are included in the select list. See the next section for selecting fields from the result set.
 
 Selecting Specific Fields
 -------------------------
@@ -767,7 +801,7 @@ The SQL that would be executed:
 SELECT * FROM articles WHERE id > 10 ORDER BY id DESC
 
 # Original query without `only`
-SELECT "articles".* FROM "articles" WHERE (id > 10) ORDER BY id desc LIMIT 20
+SELECT * FROM articles WHERE id > 10 ORDER BY id DESC LIMIT 20
 
 ```
 
@@ -786,14 +820,14 @@ Article.find(10).comments.reorder('name')
 The SQL that would be executed:
 
 ```sql
-SELECT * FROM articles WHERE id = 10
+SELECT * FROM articles WHERE id = 10 LIMIT 1
 SELECT * FROM comments WHERE article_id = 10 ORDER BY name
 ```
 
 In the case where the `reorder` clause is not used, the SQL executed would be:
 
 ```sql
-SELECT * FROM articles WHERE id = 10
+SELECT * FROM articles WHERE id = 10 LIMIT 1
 SELECT * FROM comments WHERE article_id = 10 ORDER BY posted_at DESC
 ```
 
@@ -990,13 +1024,13 @@ There are multiple ways to use the `joins` method.
 You can just supply the raw SQL specifying the `JOIN` clause to `joins`:
 
 ```ruby
-Author.joins("INNER JOIN posts ON posts.author_id = author.id AND posts.published = 't'")
+Author.joins("INNER JOIN posts ON posts.author_id = authors.id AND posts.published = 't'")
 ```
 
 This will result in the following SQL:
 
 ```sql
-SELECT clients.* FROM clients INNER JOIN posts ON posts.author_id = author.id AND posts.published = 't'
+SELECT authors.* FROM authors INNER JOIN posts ON posts.author_id = authors.id AND posts.published = 't'
 ```
 
 #### Using Array/Hash of Named Associations
@@ -1057,7 +1091,7 @@ This produces:
 
 ```sql
 SELECT articles.* FROM articles
-  INNER JOIN categories ON articles.category_id = categories.id
+  INNER JOIN categories ON categories.id = articles.category_id
   INNER JOIN comments ON comments.article_id = articles.id
 ```
 
@@ -1227,7 +1261,8 @@ articles, all the articles would still be loaded. By using `joins` (an INNER
 JOIN), the join conditions **must** match, otherwise no records will be
 returned.
 
-
+NOTE: If an association is eager loaded as part of a join, any fields from a custom select clause will not present be on the loaded models.
+This is because it is ambiguous whether they should appear on the parent record, or the child.
 
 Scopes
 ------
@@ -1357,8 +1392,9 @@ class Client < ApplicationRecord
 end
 ```
 
-NOTE: The `default_scope` is also applied while creating/building a record.
-It is not applied while updating a record. E.g.:
+NOTE: The `default_scope` is also applied while creating/building a record
+when the scope arguments are given as a `Hash`. It is not applied while
+updating a record. E.g.:
 
 ```ruby
 class Client < ApplicationRecord
@@ -1369,6 +1405,17 @@ Client.new          # => #<Client id: nil, active: true>
 Client.unscoped.new # => #<Client id: nil, active: nil>
 ```
 
+Be aware that, when given in the `Array` format, `default_scope` query arguments
+cannot be converted to a `Hash` for default attribute assignment. E.g.:
+
+```ruby
+class Client < ApplicationRecord
+  default_scope { where("active = ?", true) }
+end
+
+Client.new # => #<Client id: nil, active: nil>
+```
+
 ### Merging of scopes
 
 Just like `where` clauses scopes are merged using `AND` conditions.
@@ -1492,7 +1539,7 @@ Read the full documentation about enums
 Understanding The Method Chaining
 ---------------------------------
 
-The Active Record pattern implements [Method Chaining](http://en.wikipedia.org/wiki/Method_chaining),
+The Active Record pattern implements [Method Chaining](https://en.wikipedia.org/wiki/Method_chaining),
 which allow us to use multiple Active Record methods together in a simple and straightforward way.
 
 You can chain methods in a statement when the previous method called returns an
@@ -1520,7 +1567,7 @@ SELECT people.id, people.name, comments.text
 FROM people
 INNER JOIN comments
   ON comments.person_id = people.id
-WHERE comments.created_at = '2015-01-01'
+WHERE comments.created_at > '2015-01-01'
 ```
 
 ### Retrieving specific data from multiple tables
@@ -1665,10 +1712,10 @@ Client.find_by_sql("SELECT * FROM clients
 
 ### `select_all`
 
-`find_by_sql` has a close relative called `connection#select_all`. `select_all` will retrieve objects from the database using custom SQL just like `find_by_sql` but will not instantiate them. Instead, you will get an array of hashes where each hash indicates a record.
+`find_by_sql` has a close relative called `connection#select_all`. `select_all` will retrieve objects from the database using custom SQL just like `find_by_sql` but will not instantiate them. This method will return an instance of `ActiveRecord::Result` class and calling `to_hash` on this object would return you an array of hashes where each hash indicates a record.
 
 ```ruby
-Client.connection.select_all("SELECT first_name, created_at FROM clients WHERE id = '1'")
+Client.connection.select_all("SELECT first_name, created_at FROM clients WHERE id = '1'").to_hash
 # => [
 #   {"first_name"=>"Rafael", "created_at"=>"2012-11-10 23:23:45.281189"},
 #   {"first_name"=>"Eileen", "created_at"=>"2013-12-09 11:22:35.221282"}
@@ -1824,14 +1871,14 @@ All calculation methods work directly on a model:
 
 ```ruby
 Client.count
-# SELECT count(*) AS count_all FROM clients
+# SELECT COUNT(*) FROM clients
 ```
 
 Or on a relation:
 
 ```ruby
 Client.where(first_name: 'Ryan').count
-# SELECT count(*) AS count_all FROM clients WHERE (first_name = 'Ryan')
+# SELECT COUNT(*) FROM clients WHERE (first_name = 'Ryan')
 ```
 
 You can also use various finder methods on a relation for performing complex calculations:
@@ -1843,9 +1890,9 @@ Client.includes("orders").where(first_name: 'Ryan', orders: { status: 'received'
 Which will execute:
 
 ```sql
-SELECT count(DISTINCT clients.id) AS count_all FROM clients
-  LEFT OUTER JOIN orders ON orders.client_id = client.id WHERE
-  (clients.first_name = 'Ryan' AND orders.status = 'received')
+SELECT COUNT(DISTINCT clients.id) FROM clients
+  LEFT OUTER JOIN orders ON orders.client_id = clients.id
+  WHERE (clients.first_name = 'Ryan' AND orders.status = 'received')
 ```
 
 ### Count
@@ -1998,4 +2045,4 @@ following pointers may be helpful:
 
 * MariaDB: [EXPLAIN](https://mariadb.com/kb/en/mariadb/explain/)
 
-* PostgreSQL: [Using EXPLAIN](http://www.postgresql.org/docs/current/static/using-explain.html)
+* PostgreSQL: [Using EXPLAIN](https://www.postgresql.org/docs/current/static/using-explain.html)
diff --git a/guides/source/active_record_validations.md b/guides/source/active_record_validations.md
index 2737237c1a..e9157f3db1 100644
--- a/guides/source/active_record_validations.md
+++ b/guides/source/active_record_validations.md
@@ -290,7 +290,7 @@ You can also pass custom message via the `message` option.
 
 ```ruby
 class Person < ApplicationRecord
-  validates :terms_of_service, acceptance: true, message: 'must be abided'
+  validates :terms_of_service, acceptance: { message: 'must be abided' }
 end
 ```
 
@@ -490,9 +490,6 @@ If you set `:only_integer` to `true`, then it will use the
 regular expression to validate the attribute's value. Otherwise, it will try to
 convert the value to a number using `Float`.
 
-WARNING. Note that the regular expression above allows a trailing newline
-character.
-
 ```ruby
 class Player < ApplicationRecord
   validates :points, numericality: true
@@ -641,7 +638,7 @@ class Holiday < ApplicationRecord
     message: "should happen once per year" }
 end
 ```
-Should you wish to create a database constraint to prevent possible violations of a uniqueness validation using the `:scope` option, you must create a unique index on both columns in your database. See [the MySQL manual](http://dev.mysql.com/doc/refman/5.7/en/multiple-column-indexes.html) for more details about multiple column indexes or [the PostgreSQL manual](http://www.postgresql.org/docs/current/static/ddl-constraints.html) for examples of unique constraints that refer to a group of columns.
+Should you wish to create a database constraint to prevent possible violations of a uniqueness validation using the `:scope` option, you must create a unique index on both columns in your database. See [the MySQL manual](http://dev.mysql.com/doc/refman/5.7/en/multiple-column-indexes.html) for more details about multiple column indexes or [the PostgreSQL manual](https://www.postgresql.org/docs/current/static/ddl-constraints.html) for examples of unique constraints that refer to a group of columns.
 
 There is also a `:case_sensitive` option that you can use to define whether the
 uniqueness constraint will be case sensitive or not. This option defaults to
@@ -895,7 +892,7 @@ Conditional Validation
 
 Sometimes it will make sense to validate an object only when a given predicate
 is satisfied. You can do that by using the `:if` and `:unless` options, which
-can take a symbol, a string, a `Proc` or an `Array`. You may use the `:if`
+can take a symbol, a `Proc` or an `Array`. You may use the `:if`
 option when you want to specify when the validation **should** happen. If you
 want to specify when the validation **should not** happen, then you may use the
 `:unless` option.
@@ -916,18 +913,6 @@ class Order < ApplicationRecord
 end
 ```
 
-### Using a String with `:if` and `:unless`
-
-You can also use a string that will be evaluated using `eval` and needs to
-contain valid Ruby code. You should use this option only when the string
-represents a really short condition.
-
-```ruby
-class Person < ApplicationRecord
-  validates :surname, presence: true, if: "name.nil?"
-end
-```
-
 ### Using a Proc with `:if` and `:unless`
 
 Finally, it's possible to associate `:if` and `:unless` with a `Proc` object
@@ -968,7 +953,7 @@ should happen, an `Array` can be used. Moreover, you can apply both `:if` and
 ```ruby
 class Computer < ApplicationRecord
   validates :mouse, presence: true,
-                    if: ["market.retail?", :desktop?],
+                    if: [Proc.new  { |c| c.market.retail? }, :desktop?],
                     unless: Proc.new { |c| c.trackpad.present? }
 end
 ```
diff --git a/guides/source/active_storage_overview.md b/guides/source/active_storage_overview.md
new file mode 100644
index 0000000000..ec90e44358
--- /dev/null
+++ b/guides/source/active_storage_overview.md
@@ -0,0 +1,559 @@
+**DO NOT READ THIS FILE ON GITHUB, GUIDES ARE PUBLISHED ON http://guides.rubyonrails.org.**
+
+Active Storage Overview
+=======================
+
+This guide covers how to attach files to your Active Record models.
+
+After reading this guide, you will know:
+
+* How to attach one or many files to a record.
+* How to delete an attached file.
+* How to link to an attached file.
+* How to use variants to transform images.
+* How to generate an image representation of a non-image file, such as a PDF or a video.
+* How to send file uploads directly from browsers to a storage service,
+  bypassing your application servers.
+* How to clean up files stored during testing.
+* How to implement support for additional storage services.
+
+--------------------------------------------------------------------------------
+
+What is Active Storage?
+-----------------------
+
+Active Storage facilitates uploading files to a cloud storage service like
+Amazon S3, Google Cloud Storage, or Microsoft Azure Storage and attaching those
+files to Active Record objects. It comes with a local disk-based service for
+development and testing and supports mirroring files to subordinate services for
+backups and migrations.
+
+Using Active Storage, an application can transform image uploads with
+[ImageMagick](https://www.imagemagick.org), generate image representations of
+non-image uploads like PDFs and videos, and extract metadata from arbitrary
+files.
+
+## Setup
+
+Active Storage uses two tables in your application’s database named
+`active_storage_blobs` and `active_storage_attachments`. After upgrading your
+application to Rails 5.2, run `rails active_storage:install` to generate a
+migration that creates these tables. Use `rails db:migrate` to run the
+migration.
+
+You need not run `rails active_storage:install` in a new Rails 5.2 application:
+the migration is generated automatically.
+
+Declare Active Storage services in `config/storage.yml`. For each service your
+application uses, provide a name and the requisite configuration. The example
+below declares three services named `local`, `test`, and `amazon`:
+
+```yaml
+local:
+  service: Disk
+  root: <%= Rails.root.join("storage") %>
+
+test:
+  service: Disk
+  root: <%= Rails.root.join("tmp/storage") %>
+
+amazon:
+  service: S3
+  access_key_id: ""
+  secret_access_key: ""
+```
+
+Tell Active Storage which service to use by setting
+`Rails.application.config.active_storage.service`. Because each environment will
+likely use a different service, it is recommended to do this on a
+per-environment basis. To use the disk service from the previous example in the
+development environment, you would add the following to
+`config/environments/development.rb`:
+
+```ruby
+# Store files locally.
+config.active_storage.service = :local
+```
+
+To use the Amazon S3 service in production, you add the following to
+`config/environments/production.rb`:
+
+```ruby
+# Store files on Amazon S3.
+config.active_storage.service = :amazon
+```
+
+Continue reading for more information on the built-in service adapters (e.g.
+`Disk` and `S3`) and the configuration they require.
+
+### Disk Service
+
+Declare a Disk service in `config/storage.yml`:
+
+```yaml
+local:
+  service: Disk
+  root: <%= Rails.root.join("storage") %>
+```
+
+### Amazon S3 Service
+
+Declare an S3 service in `config/storage.yml`:
+
+```yaml
+amazon:
+  service: S3
+  access_key_id: ""
+  secret_access_key: ""
+  region: ""
+  bucket: ""
+```
+
+Add the [`aws-sdk-s3`](https://github.com/aws/aws-sdk-ruby) gem to your `Gemfile`:
+
+```ruby
+gem "aws-sdk-s3", require: false
+```
+
+### Microsoft Azure Storage Service
+
+Declare an Azure Storage service in `config/storage.yml`:
+
+```yaml
+azure:
+  service: AzureStorage
+  path: ""
+  storage_account_name: ""
+  storage_access_key: ""
+  container: ""
+```
+
+Add the [`azure-storage`](https://github.com/Azure/azure-storage-ruby) gem to your `Gemfile`:
+
+```ruby
+gem "azure-storage", require: false
+```
+
+### Google Cloud Storage Service
+
+Declare a Google Cloud Storage service in `config/storage.yml`:
+
+```yaml
+google:
+  service: GCS
+  credentials: <%= Rails.root.join("path/to/keyfile.json") %>
+  project: ""
+  bucket: ""
+```
+
+Optionally provide a Hash of credentials instead of a keyfile path:
+
+```yaml
+google:
+  service: GCS
+  credentials:
+    type: "service_account"
+    project_id: ""
+    private_key_id: <%= Rails.application.credentials.dig(:gcs, :private_key_id) %>
+    private_key: <%= Rails.application.credentials.dig(:gcs, :private_key) %>
+    client_email: ""
+    client_id: ""
+    auth_uri: "https://accounts.google.com/o/oauth2/auth"
+    token_uri: "https://accounts.google.com/o/oauth2/token"
+    auth_provider_x509_cert_url: "https://www.googleapis.com/oauth2/v1/certs"
+    client_x509_cert_url: ""
+  project: ""
+  bucket: ""
+```
+
+Add the [`google-cloud-storage`](https://github.com/GoogleCloudPlatform/google-cloud-ruby/tree/master/google-cloud-storage) gem to your `Gemfile`:
+
+```ruby
+gem "google-cloud-storage", "~> 1.3", require: false
+```
+
+### Mirror Service
+
+You can keep multiple services in sync by defining a mirror service. When a file
+is uploaded or deleted, it's done across all the mirrored services. Mirrored
+services can be used to facilitate a migration between services in production.
+You can start mirroring to the new service, copy existing files from the old
+service to the new, then go all-in on the new service. Define each of the
+services you'd like to use as described above and reference them from a mirrored
+service.
+
+```yaml
+s3_west_coast:
+  service: S3
+  access_key_id: ""
+  secret_access_key: ""
+  region: ""
+  bucket: ""
+
+s3_east_coast:
+  service: S3
+  access_key_id: ""
+  secret_access_key: ""
+  region: ""
+  bucket: ""
+
+production:
+  service: Mirror
+  primary: s3_east_coast
+  mirrors:
+    - s3_west_coast
+```
+
+NOTE: Files are served from the primary service.
+
+Attaching Files to Records
+--------------------------
+
+### `has_one_attached`
+
+The `has_one_attached` macro sets up a one-to-one mapping between records and
+files. Each record can have one file attached to it.
+
+For example, suppose your application has a `User` model. If you want each user to
+have an avatar, define the `User` model like this:
+
+```ruby
+class User < ApplicationRecord
+  has_one_attached :avatar
+end
+```
+
+You can create a user with an avatar:
+
+```ruby
+class SignupController < ApplicationController
+  def create
+    user = User.create!(user_params)
+    session[:user_id] = user.id
+    redirect_to root_path
+  end
+
+  private
+    def user_params
+      params.require(:user).permit(:email_address, :password, :avatar)
+    end
+end
+```
+
+Call `avatar.attach` to attach an avatar to an existing user:
+
+```ruby
+Current.user.avatar.attach(params[:avatar])
+```
+
+Call `avatar.attached?` to determine whether a particular user has an avatar:
+
+```ruby
+Current.user.avatar.attached?
+```
+
+### `has_many_attached`
+
+The `has_many_attached` macro sets up a one-to-many relationship between records
+and files. Each record can have many files attached to it.
+
+For example, suppose your application has a `Message` model. If you want each
+message to have many images, define the `Message` model like this:
+
+```ruby
+class Message < ApplicationRecord
+  has_many_attached :images
+end
+```
+
+You can create a message with images:
+
+```ruby
+class MessagesController < ApplicationController
+  def create
+    message = Message.create!(message_params)
+    redirect_to message
+  end
+
+  private
+    def message_params
+      params.require(:message).permit(:title, :content, images: [])
+    end
+end
+```
+
+Call `images.attach` to add new images to an existing message:
+
+```ruby
+@message.images.attach(params[:images])
+```
+
+Call `images.attached?` to determine whether a particular message has any images:
+
+```ruby
+@message.images.attached?
+```
+
+Removing Files
+--------------
+
+To remove an attachment from a model, call `purge` on the attachment. Removal
+can be done in the background if your application is setup to use Active Job.
+Purging deletes the blob and the file from the storage service.
+
+```ruby
+# Synchronously destroy the avatar and actual resource files.
+user.avatar.purge
+
+# Destroy the associated models and actual resource files async, via Active Job.
+user.avatar.purge_later
+```
+
+Linking to Files
+----------------
+
+Generate a permanent URL for the blob that points to the application. Upon
+access, a redirect to the actual service endpoint is returned. This indirection
+decouples the public URL from the actual one, and allows, for example, mirroring
+attachments in different services for high-availability. The redirection has an
+HTTP expiration of 5 min.
+
+```ruby
+url_for(user.avatar)
+```
+
+To create a download link, use the `rails_blob_{path|url}` helper. Using this
+helper allows you to set the disposition.
+
+```ruby
+rails_blob_path(user.avatar, disposition: "attachment")
+```
+
+Transforming Images
+-------------------
+
+To create variation of the image, call `variant` on the Blob.
+You can pass any [MiniMagick](https://github.com/minimagick/minimagick)
+supported transformation to the method.
+
+To enable variants, add `mini_magick` to your `Gemfile`:
+
+```ruby
+gem 'mini_magick'
+```
+
+When the browser hits the variant URL, Active Storage will lazy transform the
+original blob into the format you specified and redirect to its new service
+location.
+
+```erb
+<%= image_tag user.avatar.variant(resize: "100x100") %>
+```
+
+Previewing Files
+----------------
+
+Some non-image files can be previewed: that is, they can be presented as images.
+For example, a video file can be previewed by extracting its first frame. Out of
+the box, Active Storage supports previewing videos and PDF documents.
+
+```erb
+<ul>
+  <% @message.files.each do |file| %>
+    <li>
+      <%= image_tag file.preview(resize: "100x100>") %>
+    </li>
+  <% end %>
+</ul>
+```
+
+WARNING: Extracting previews requires third-party applications, `ffmpeg` for
+video and `mutool` for PDFs. These libraries are not provided by Rails. You must
+install them yourself to use the built-in previewers. Before you install and use
+third-party software, make sure you understand the licensing implications of
+doing so.
+
+Direct Uploads
+--------------
+
+Active Storage, with its included JavaScript library, supports uploading
+directly from the client to the cloud.
+
+### Direct upload installation
+
+1. Include `activestorage.js` in your application's JavaScript bundle.
+
+    Using the asset pipeline:
+
+    ```js
+    //= require activestorage
+
+    ```
+
+    Using the npm package:
+
+    ```js
+    import * as ActiveStorage from "activestorage"
+    ActiveStorage.start()
+    ```
+
+2. Annotate file inputs with the direct upload URL.
+
+    ```ruby
+    <%= form.file_field :attachments, multiple: true, direct_upload: true %>
+    ```
+3. That's it! Uploads begin upon form submission.
+
+### Direct upload JavaScript events
+
+| Event name | Event target | Event data (`event.detail`) | Description |
+| --- | --- | --- | --- |
+| `direct-uploads:start` | `<form>` | None | A form containing files for direct upload fields was submitted. |
+| `direct-upload:initialize` | `<input>` | `{id, file}` | Dispatched for every file after form submission. |
+| `direct-upload:start` | `<input>` | `{id, file}` | A direct upload is starting. |
+| `direct-upload:before-blob-request` | `<input>` | `{id, file, xhr}` | Before making a request to your application for direct upload metadata. |
+| `direct-upload:before-storage-request` | `<input>` | `{id, file, xhr}` | Before making a request to store a file. |
+| `direct-upload:progress` | `<input>` | `{id, file, progress}` | As requests to store files progress. |
+| `direct-upload:error` | `<input>` | `{id, file, error}` | An error occurred. An `alert` will display unless this event is canceled. |
+| `direct-upload:end` | `<input>` | `{id, file}` | A direct upload has ended. |
+| `direct-uploads:end` | `<form>` | None | All direct uploads have ended. |
+
+### Example
+
+You can use these events to show the progress of an upload.
+
+![direct-uploads](https://user-images.githubusercontent.com/5355/28694528-16e69d0c-72f8-11e7-91a7-c0b8cfc90391.gif)
+
+To show the uploaded files in a form:
+
+```js
+// direct_uploads.js
+
+addEventListener("direct-upload:initialize", event => {
+  const { target, detail } = event
+  const { id, file } = detail
+  target.insertAdjacentHTML("beforebegin", `
+    <div id="direct-upload-${id}" class="direct-upload direct-upload--pending">
+      <div id="direct-upload-progress-${id}" class="direct-upload__progress" style="width: 0%"></div>
+      <span class="direct-upload__filename">${file.name}</span>
+    </div>
+  `)
+})
+
+addEventListener("direct-upload:start", event => {
+  const { id } = event.detail
+  const element = document.getElementById(`direct-upload-${id}`)
+  element.classList.remove("direct-upload--pending")
+})
+
+addEventListener("direct-upload:progress", event => {
+  const { id, progress } = event.detail
+  const progressElement = document.getElementById(`direct-upload-progress-${id}`)
+  progressElement.style.width = `${progress}%`
+})
+
+addEventListener("direct-upload:error", event => {
+  event.preventDefault()
+  const { id, error } = event.detail
+  const element = document.getElementById(`direct-upload-${id}`)
+  element.classList.add("direct-upload--error")
+  element.setAttribute("title", error)
+})
+
+addEventListener("direct-upload:end", event => {
+  const { id } = event.detail
+  const element = document.getElementById(`direct-upload-${id}`)
+  element.classList.add("direct-upload--complete")
+})
+```
+
+Add styles:
+
+```css
+/* direct_uploads.css */
+
+.direct-upload {
+  display: inline-block;
+  position: relative;
+  padding: 2px 4px;
+  margin: 0 3px 3px 0;
+  border: 1px solid rgba(0, 0, 0, 0.3);
+  border-radius: 3px;
+  font-size: 11px;
+  line-height: 13px;
+}
+
+.direct-upload--pending {
+  opacity: 0.6;
+}
+
+.direct-upload__progress {
+  position: absolute;
+  top: 0;
+  left: 0;
+  bottom: 0;
+  opacity: 0.2;
+  background: #0076ff;
+  transition: width 120ms ease-out, opacity 60ms 60ms ease-in;
+  transform: translate3d(0, 0, 0);
+}
+
+.direct-upload--complete .direct-upload__progress {
+  opacity: 0.4;
+}
+
+.direct-upload--error {
+  border-color: red;
+}
+
+input[type=file][data-direct-upload-url][disabled] {
+  display: none;
+}
+```
+
+Discarding Files Stored During System Tests
+-------------------------------------------
+
+System tests clean up test data by rolling back a transaction. Because destroy
+is never called on an object, the attached files are never cleaned up. If you
+want to clear the files, you can do it in an `after_teardown` callback. Doing it
+here ensures that all connections created during the test are complete and
+you won't receive an error from Active Storage saying it can't find a file.
+
+```ruby
+class ApplicationSystemTestCase < ActionDispatch::SystemTestCase
+  driven_by :selenium, using: :chrome, screen_size: [1400, 1400]
+
+  def remove_uploaded_files
+    FileUtils.rm_rf("#{Rails.root}/storage_test")
+  end
+
+  def after_teardown
+    super
+    remove_uploaded_files
+  end
+end
+```
+
+If your system tests verify the deletion of a model with attachments and you're
+using Active Job, set your test environment to use the inline queue adapter so
+the purge job is executed immediately rather at an unknown time in the future.
+
+You may also want to use a separate service definition for the test environment
+so your tests don't delete the files you create during development.
+
+```ruby
+# Use inline job processing to make things happen immediately
+config.active_job.queue_adapter = :inline
+
+# Separate file storage in the test environment
+config.active_storage.service = :local_test
+```
+
+Implementing Support for Other Cloud Services
+---------------------------------------------
+
+If you need to support a cloud service other than these, you will need to
+implement the Service. Each service extends
+[`ActiveStorage::Service`](https://github.com/rails/rails/blob/master/activestorage/lib/active_storage/service.rb)
+by implementing the methods necessary to upload and download files to the cloud.
diff --git a/guides/source/active_support_core_extensions.md b/guides/source/active_support_core_extensions.md
index 565c87c4b5..8e2826bb85 100644
--- a/guides/source/active_support_core_extensions.md
+++ b/guides/source/active_support_core_extensions.md
@@ -135,36 +135,53 @@ NOTE: Defined in `active_support/core_ext/object/blank.rb`.
 
 ### `duplicable?`
 
-A few fundamental objects in Ruby are singletons. For example, in the whole life of a program the integer 1 refers always to the same instance:
+In Ruby 2.4 most objects can be duplicated via `dup` or `clone` except
+methods and certain numbers. Though Ruby 2.2 and 2.3 can't duplicate `nil`,
+`false`, `true`, and  symbols as well as instances `Float`, `Fixnum`,
+and `Bignum` instances.
 
 ```ruby
-1.object_id                 # => 3
-Math.cos(0).to_i.object_id  # => 3
+"foo".dup           # => "foo"
+"".dup              # => ""
+1.method(:+).dup    # => TypeError: allocator undefined for Method
+Complex(0).dup      # => TypeError: can't copy Complex
 ```
 
-Hence, there's no way these objects can be duplicated through `dup` or `clone`:
+Active Support provides `duplicable?` to query an object about this:
 
 ```ruby
-true.dup  # => TypeError: can't dup TrueClass
+"foo".duplicable?           # => true
+"".duplicable?              # => true
+Rational(1).duplicable?     # => false
+Complex(1).duplicable?      # => false
+1.method(:+).duplicable?    # => false
 ```
 
-Some numbers which are not singletons are not duplicable either:
+`duplicable?` matches Ruby's `dup` according to the Ruby version.
+
+So in 2.4:
 
 ```ruby
-0.0.clone        # => allocator undefined for Float
-(2**1024).clone  # => allocator undefined for Bignum
+nil.dup                 # => nil
+:my_symbol.dup          # => :my_symbol
+1.dup                   # => 1
+
+nil.duplicable?         # => true
+:my_symbol.duplicable?  # => true
+1.duplicable?           # => true
 ```
 
-Active Support provides `duplicable?` to programmatically query an object about this property:
+Whereas in 2.2 and 2.3:
 
 ```ruby
-"foo".duplicable? # => true
-"".duplicable?    # => true
-0.0.duplicable?   # => false
-false.duplicable? # => false
-```
+nil.dup                 # => TypeError: can't dup NilClass
+:my_symbol.dup          # => TypeError: can't dup Symbol
+1.dup                   # => TypeError: can't dup Fixnum
 
-By definition all objects are `duplicable?` except `nil`, `false`, `true`, symbols, numbers, class, module, and method objects.
+nil.duplicable?         # => false
+:my_symbol.duplicable?  # => false
+1.duplicable?           # => false
+```
 
 WARNING: Any class can disallow duplication by removing `dup` and `clone` or raising exceptions from them. Thus only `rescue` can tell whether a given arbitrary object is duplicable. `duplicable?` depends on the hard-coded list above, but it is much faster than `rescue`. Use it only if you know the hard-coded list is enough in your use case.
 
@@ -368,7 +385,7 @@ account.to_query('company[name]')
 
 so its output is ready to be used in a query string.
 
-Arrays return the result of applying `to_query` to each element with `_key_[]` as key, and join the result with "&":
+Arrays return the result of applying `to_query` to each element with `key[]` as key, and join the result with "&":
 
 ```ruby
 [3.4, -45.6].to_query('sample')
@@ -511,56 +528,6 @@ NOTE: Defined in `active_support/core_ext/object/inclusion.rb`.
 Extensions to `Module`
 ----------------------
 
-### `alias_method_chain`
-
-**This method is deprecated in favour of using Module#prepend.**
-
-Using plain Ruby you can wrap methods with other methods, that's called _alias chaining_.
-
-For example, let's say you'd like params to be strings in functional tests, as they are in real requests, but still want the convenience of assigning integers and other kind of values. To accomplish that you could wrap `ActionDispatch::IntegrationTest#process` this way in `test/test_helper.rb`:
-
-```ruby
-ActionDispatch::IntegrationTest.class_eval do
-  # save a reference to the original process method
-  alias_method :original_process, :process
-
-  # now redefine process and delegate to original_process
-  def process('GET', path, params: nil, headers: nil, env: nil, xhr: false)
-    params = Hash[*params.map {|k, v| [k, v.to_s]}.flatten]
-    original_process('GET', path, params: params)
-  end
-end
-```
-
-That's the method `get`, `post`, etc., delegate the work to.
-
-That technique has a risk, it could be the case that `:original_process` was taken. To try to avoid collisions people choose some label that characterizes what the chaining is about:
-
-```ruby
-ActionDispatch::IntegrationTest.class_eval do
-  def process_with_stringified_params(...)
-    params = Hash[*params.map {|k, v| [k, v.to_s]}.flatten]
-    process_without_stringified_params(method, path, params: params)
-  end
-  alias_method :process_without_stringified_params, :process
-  alias_method :process, :process_with_stringified_params
-end
-```
-
-The method `alias_method_chain` provides a shortcut for that pattern:
-
-```ruby
-ActionDispatch::IntegrationTest.class_eval do
-  def process_with_stringified_params(...)
-    params = Hash[*params.map {|k, v| [k, v.to_s]}.flatten]
-    process_without_stringified_params(method, path, params: params)
-  end
-  alias_method_chain :process, :stringified_params
-end
-```
-
-NOTE: Defined in `active_support/core_ext/module/aliasing.rb`.
-
 ### Attributes
 
 #### `alias_attribute`
@@ -667,7 +634,7 @@ NOTE: Defined in `active_support/core_ext/module/introspection.rb`.
 
 #### `parent_name`
 
-The `parent_name` method on a nested named module returns the fully-qualified name of the module that contains its corresponding constant:
+The `parent_name` method on a nested named module returns the fully qualified name of the module that contains its corresponding constant:
 
 ```ruby
 module X
@@ -707,44 +674,6 @@ M.parents       # => [X::Y, X, Object]
 
 NOTE: Defined in `active_support/core_ext/module/introspection.rb`.
 
-### Reachable
-
-A named module is reachable if it is stored in its corresponding constant. It means you can reach the module object via the constant.
-
-That is what ordinarily happens, if a module is called "M", the `M` constant exists and holds it:
-
-```ruby
-module M
-end
-
-M.reachable? # => true
-```
-
-But since constants and modules are indeed kind of decoupled, module objects can become unreachable:
-
-```ruby
-module M
-end
-
-orphan = Object.send(:remove_const, :M)
-
-# The module object is orphan now but it still has a name.
-orphan.name # => "M"
-
-# You cannot reach it via the constant M because it does not even exist.
-orphan.reachable? # => false
-
-# Let's define a module called "M" again.
-module M
-end
-
-# The constant M exists now again, and it stores a module
-# object called "M", but it is a new instance.
-orphan.reachable? # => false
-```
-
-NOTE: Defined in `active_support/core_ext/module/reachable.rb`.
-
 ### Anonymous
 
 A module may or may not have a name:
@@ -778,7 +707,6 @@ end
 
 m = Object.send(:remove_const, :M)
 
-m.reachable? # => false
 m.anonymous? # => false
 ```
 
@@ -788,6 +716,8 @@ NOTE: Defined in `active_support/core_ext/module/anonymous.rb`.
 
 ### Method Delegation
 
+#### `delegate`
+
 The macro `delegate` offers an easy way to forward methods.
 
 Let's imagine that users in some application have login information in the `User` model but name and other data in a separate `Profile` model:
@@ -870,13 +800,36 @@ In the previous example the macro generates `avatar_size` rather than `size`.
 
 NOTE: Defined in `active_support/core_ext/module/delegation.rb`
 
+#### `delegate_missing_to`
+
+Imagine you would like to delegate everything missing from the `User` object,
+to the `Profile` one. The `delegate_missing_to` macro lets you implement this
+in a breeze:
+
+```ruby
+class User < ApplicationRecord
+  has_one :profile
+
+  delegate_missing_to :profile
+end
+```
+
+The target can be anything callable within the object, e.g. instance variables,
+methods, constants, etc. Only the public methods of the target are delegated.
+
+NOTE: Defined in `active_support/core_ext/module/delegation.rb`.
+
 ### Redefining Methods
 
 There are cases where you need to define a method with `define_method`, but don't know whether a method with that name already exists. If it does, a warning is issued if they are enabled. No big deal, but not clean either.
 
 The method `redefine_method` prevents such a potential warning, removing the existing method before if needed.
 
-NOTE: Defined in `active_support/core_ext/module/remove_method.rb`
+You can also use `silence_redefinition_of_method` if you need to define
+the replacement method yourself (because you're using `delegate`, for
+example).
+
+NOTE: Defined in `active_support/core_ext/module/redefine_method.rb`.
 
 Extensions to `Class`
 ---------------------
@@ -939,8 +892,7 @@ The generation of the writer instance method can be prevented by setting the opt
 ```ruby
 module ActiveRecord
   class Base
-    class_attribute :table_name_prefix, instance_writer: false
-    self.table_name_prefix = ""
+    class_attribute :table_name_prefix, instance_writer: false, default: "my"
   end
 end
 ```
@@ -954,7 +906,8 @@ class A
   class_attribute :x, instance_reader: false
 end
 
-A.new.x = 1 # NoMethodError
+A.new.x = 1
+A.new.x # NoMethodError
 ```
 
 For convenience `class_attribute` also defines an instance predicate which is the double negation of what the instance reader returns. In the examples above it would be called `x?`.
@@ -963,7 +916,7 @@ When `:instance_reader` is `false`, the instance predicate returns a `NoMethodEr
 
 If you do not want the instance predicate, pass `instance_predicate: false` and it will not be defined.
 
-NOTE: Defined in `active_support/core_ext/class/attribute.rb`
+NOTE: Defined in `active_support/core_ext/class/attribute.rb`.
 
 #### `cattr_reader`, `cattr_writer`, and `cattr_accessor`
 
@@ -972,8 +925,7 @@ The macros `cattr_reader`, `cattr_writer`, and `cattr_accessor` are analogous to
 ```ruby
 class MysqlAdapter < AbstractAdapter
   # Generates class methods to access @@emulate_booleans.
-  cattr_accessor :emulate_booleans
-  self.emulate_booleans = true
+  cattr_accessor :emulate_booleans, default: true
 end
 ```
 
@@ -982,8 +934,7 @@ Instance methods are created as well for convenience, they are just proxies to t
 ```ruby
 module ActionView
   class Base
-    cattr_accessor :field_error_proc
-    @@field_error_proc = Proc.new{ ... }
+    cattr_accessor :field_error_proc, default: Proc.new { ... }
   end
 end
 ```
@@ -995,7 +946,7 @@ Also, you can pass a block to `cattr_*` to set up the attribute with a default v
 ```ruby
 class MysqlAdapter < AbstractAdapter
   # Generates class methods to access @@emulate_booleans with default value of true.
-  cattr_accessor(:emulate_booleans) { true }
+  cattr_accessor :emulate_booleans, default: true
 end
 ```
 
@@ -1723,7 +1674,7 @@ Specifically performs these transformations:
   * Capitalizes the first word.
 
 The capitalization of the first word can be turned off by setting the
-+:capitalize+ option to false (default is true).
+`:capitalize` option to false (default is true).
 
 ```ruby
 "name".humanize                         # => "Name"
@@ -1801,7 +1752,7 @@ The methods `to_date`, `to_time`, and `to_datetime` are basically convenience wr
 "2010-07-27 23:42:00".to_time(:local) # => 2010-07-27 23:42:00 +0200
 ```
 
-Default is `:utc`.
+Default is `:local`.
 
 Please refer to the documentation of `Date._parse` for further details.
 
@@ -1845,7 +1796,7 @@ NOTE: Defined in `active_support/core_ext/numeric/bytes.rb`.
 
 ### Time
 
-Enables the use of time calculations and declarations, like `45.minutes + 2.hours + 4.years`.
+Enables the use of time calculations and declarations, like `45.minutes + 2.hours + 4.weeks`.
 
 These methods use Time#advance for precise date calculations when using from_now, ago, etc.
 as well as adding or subtracting their results from a Time object. For example:
@@ -1854,14 +1805,16 @@ as well as adding or subtracting their results from a Time object. For example:
 # equivalent to Time.current.advance(months: 1)
 1.month.from_now
 
-# equivalent to Time.current.advance(years: 2)
-2.years.from_now
+# equivalent to Time.current.advance(weeks: 2)
+2.weeks.from_now
 
-# equivalent to Time.current.advance(months: 4, years: 5)
-(4.months + 5.years).from_now
+# equivalent to Time.current.advance(months: 4, weeks: 5)
+(4.months + 5.weeks).from_now
 ```
 
-NOTE: Defined in `active_support/core_ext/numeric/time.rb`
+WARNING. For other durations please refer to the time extensions to `Integer`.
+
+NOTE: Defined in `active_support/core_ext/numeric/time.rb`.
 
 ### Formatting
 
@@ -1996,6 +1949,28 @@ The method `ordinalize` returns the ordinal string corresponding to the receiver
 
 NOTE: Defined in `active_support/core_ext/integer/inflections.rb`.
 
+### Time
+
+Enables the use of time calculations and declarations, like `4.months + 5.years`.
+
+These methods use Time#advance for precise date calculations when using from_now, ago, etc.
+as well as adding or subtracting their results from a Time object. For example:
+
+```ruby
+# equivalent to Time.current.advance(months: 1)
+1.month.from_now
+
+# equivalent to Time.current.advance(years: 2)
+2.years.from_now
+
+# equivalent to Time.current.advance(months: 4, years: 5)
+(4.months + 5.years).from_now
+```
+
+WARNING. For other durations please refer to the time extensions to `Numeric`.
+
+NOTE: Defined in `active_support/core_ext/integer/time.rb`.
+
 Extensions to `BigDecimal`
 --------------------------
 ### `to_s`
@@ -2003,19 +1978,19 @@ Extensions to `BigDecimal`
 The method `to_s` provides a default specifier of "F". This means that a simple call to `to_s` will result in floating point representation instead of engineering notation:
 
 ```ruby
-BigDecimal.new(5.00, 6).to_s  # => "5.0"
+BigDecimal(5.00, 6).to_s       # => "5.0"
 ```
 
 and that symbol specifiers are also supported:
 
 ```ruby
-BigDecimal.new(5.00, 6).to_s(:db)  # => "5.0"
+BigDecimal(5.00, 6).to_s(:db)  # => "5.0"
 ```
 
 Engineering notation is still supported:
 
 ```ruby
-BigDecimal.new(5.00, 6).to_s("e")  # => "0.5E1"
+BigDecimal(5.00, 6).to_s("e")  # => "0.5E1"
 ```
 
 Extensions to `Enumerable`
@@ -2035,7 +2010,7 @@ Addition only assumes the elements respond to `+`:
 ```ruby
 [[1, 2], [2, 3], [3, 4]].sum    # => [1, 2, 2, 3, 3, 4]
 %w(foo bar baz).sum             # => "foobarbaz"
-{a: 1, b: 2, c: 3}.sum # => [:b, 2, :c, 3, :a, 1]
+{a: 1, b: 2, c: 3}.sum          # => [:b, 2, :c, 3, :a, 1]
 ```
 
 The sum of an empty collection is zero by default, but this is customizable:
@@ -2373,7 +2348,7 @@ This method is similar in purpose to `Kernel#Array`, but there are some differen
 
 * If the argument responds to `to_ary` the method is invoked. `Kernel#Array` moves on to try `to_a` if the returned value is `nil`, but `Array.wrap` returns an array with the argument as its single element right away.
 * If the returned value from `to_ary` is neither `nil` nor an `Array` object, `Kernel#Array` raises an exception, while `Array.wrap` does not, it just returns the value.
-* It does not call `to_a` on the argument, if the argument does not respond to +to_ary+ it returns an array with the argument as its single element.
+* It does not call `to_a` on the argument, if the argument does not respond to `to_ary` it returns an array with the argument as its single element.
 
 The last point is particularly worth comparing for some enumerables:
 
@@ -2660,7 +2635,7 @@ The method `transform_keys` accepts a block and returns a hash that has applied
 
 ```ruby
 {nil => nil, 1 => 1, a: :a}.transform_keys { |key| key.to_s.upcase }
-# => {"" => nil, "A" => :a, "1" => 1}
+# => {"" => nil, "1" => 1, "A" => :a}
 ```
 
 In case of key collision, one of the values will be chosen. The chosen value may not always be the same given the same hash:
@@ -2702,7 +2677,7 @@ The method `stringify_keys` returns a hash that has a stringified version of the
 
 ```ruby
 {nil => nil, 1 => 1, a: :a}.stringify_keys
-# => {"" => nil, "a" => :a, "1" => 1}
+# => {"" => nil, "1" => 1, "a" => :a}
 ```
 
 In case of key collision, one of the values will be chosen. The chosen value may not always be the same given the same hash:
@@ -2744,7 +2719,7 @@ The method `symbolize_keys` returns a hash that has a symbolized version of the
 
 ```ruby
 {nil => nil, 1 => 1, "a" => "a"}.symbolize_keys
-# => {1=>1, nil=>nil, :a=>"a"}
+# => {nil=>nil, 1=>1, :a=>"a"}
 ```
 
 WARNING. Note in the previous example only one key was symbolized.
@@ -2821,7 +2796,7 @@ Ruby has built-in support for taking slices out of strings and arrays. Active Su
 
 ```ruby
 {a: 1, b: 2, c: 3}.slice(:a, :c)
-# => {:c=>3, :a=>1}
+# => {:a=>1, :c=>3}
 
 {a: 1, b: 2, c: 3}.slice(:b, :X)
 # => {:b=>2} # non-existing keys are ignored
@@ -2915,6 +2890,24 @@ end
 
 NOTE: Defined in `active_support/core_ext/regexp.rb`.
 
+### `match?`
+
+Rails implements `Regexp#match?` for Ruby versions prior to 2.4:
+
+```ruby
+/oo/.match?('foo')    # => true
+/oo/.match?('bar')    # => false
+/oo/.match?('foo', 1) # => true
+```
+
+The backport has the same interface and lack of side-effects in the caller like
+not setting `$1` and friends, but it does not have the speed benefits. Its
+purpose is to be able to write 2.4 compatible code. Rails itself uses this
+predicate internally for example.
+
+Active Support defines `Regexp#match?` only if not present, so code running
+under 2.4 or later does run the original one and gets the performance boost.
+
 Extensions to `Range`
 ---------------------
 
@@ -2977,6 +2970,32 @@ Extensions to `Date`
 
 NOTE: All the following methods are defined in `active_support/core_ext/date/calculations.rb`.
 
+```ruby
+yesterday
+tomorrow
+beginning_of_week (at_beginning_of_week)
+end_of_week (at_end_of_week)
+monday
+sunday
+weeks_ago
+prev_week (last_week)
+next_week
+months_ago
+months_since
+beginning_of_month (at_beginning_of_month)
+end_of_month (at_end_of_month)
+last_month
+beginning_of_quarter (at_beginning_of_quarter)
+end_of_quarter (at_end_of_quarter)
+beginning_of_year (at_beginning_of_year)
+end_of_year (at_end_of_year)
+years_ago
+years_since
+last_year
+on_weekday?
+on_weekend?
+```
+
 INFO: The following calculation methods have edge cases in October 1582, since days 5..14 just do not exist. This guide does not document their behavior around those days for brevity, but it is enough to say that they do what you would expect. That is, `Date.new(1582, 10, 4).tomorrow` returns `Date.new(1582, 10, 15)` and so on. Please check `test/core_ext/date_ext_test.rb` in the Active Support test suite for expected behavior.
 
 #### `Date.current`
@@ -2987,68 +3006,6 @@ When making Date comparisons using methods which honor the user time zone, make
 
 #### Named dates
 
-##### `prev_year`, `next_year`
-
-In Ruby 1.9 `prev_year` and `next_year` return a date with the same day/month in the last or next year:
-
-```ruby
-d = Date.new(2010, 5, 8) # => Sat, 08 May 2010
-d.prev_year              # => Fri, 08 May 2009
-d.next_year              # => Sun, 08 May 2011
-```
-
-If date is the 29th of February of a leap year, you obtain the 28th:
-
-```ruby
-d = Date.new(2000, 2, 29) # => Tue, 29 Feb 2000
-d.prev_year               # => Sun, 28 Feb 1999
-d.next_year               # => Wed, 28 Feb 2001
-```
-
-`prev_year` is aliased to `last_year`.
-
-##### `prev_month`, `next_month`
-
-In Ruby 1.9 `prev_month` and `next_month` return the date with the same day in the last or next month:
-
-```ruby
-d = Date.new(2010, 5, 8) # => Sat, 08 May 2010
-d.prev_month             # => Thu, 08 Apr 2010
-d.next_month             # => Tue, 08 Jun 2010
-```
-
-If such a day does not exist, the last day of the corresponding month is returned:
-
-```ruby
-Date.new(2000, 5, 31).prev_month # => Sun, 30 Apr 2000
-Date.new(2000, 3, 31).prev_month # => Tue, 29 Feb 2000
-Date.new(2000, 5, 31).next_month # => Fri, 30 Jun 2000
-Date.new(2000, 1, 31).next_month # => Tue, 29 Feb 2000
-```
-
-`prev_month` is aliased to `last_month`.
-
-##### `prev_quarter`, `next_quarter`
-
-Same as `prev_month` and `next_month`. It returns the date with the same day in the previous or next quarter:
-
-```ruby
-t = Time.local(2010, 5, 8) # => Sat, 08 May 2010
-t.prev_quarter             # => Mon, 08 Feb 2010
-t.next_quarter             # => Sun, 08 Aug 2010
-```
-
-If such a day does not exist, the last day of the corresponding month is returned:
-
-```ruby
-Time.local(2000, 7, 31).prev_quarter  # => Sun, 30 Apr 2000
-Time.local(2000, 5, 31).prev_quarter  # => Tue, 29 Feb 2000
-Time.local(2000, 10, 31).prev_quarter # => Mon, 30 Oct 2000
-Time.local(2000, 11, 31).next_quarter # => Wed, 28 Feb 2001
-```
-
-`prev_quarter` is aliased to `last_quarter`.
-
 ##### `beginning_of_week`, `end_of_week`
 
 The methods `beginning_of_week` and `end_of_week` return the dates for the
@@ -3166,6 +3123,8 @@ Date.new(2012, 2, 29).years_ago(3)     # => Sat, 28 Feb 2009
 Date.new(2012, 2, 29).years_since(3)   # => Sat, 28 Feb 2015
 ```
 
+`last_year` is short-hand for `#years_ago(1)`.
+
 ##### `months_ago`, `months_since`
 
 The methods `months_ago` and `months_since` work analogously for months:
@@ -3182,6 +3141,8 @@ Date.new(2010, 4, 30).months_ago(2)    # => Sun, 28 Feb 2010
 Date.new(2009, 12, 31).months_since(2) # => Sun, 28 Feb 2010
 ```
 
+`last_month` is short-hand for `#months_ago(1)`.
+
 ##### `weeks_ago`
 
 The method `weeks_ago` works analogously for weeks:
@@ -3344,35 +3305,7 @@ WARNING: `DateTime` is not aware of DST rules and so some of these methods have
 
 NOTE: All the following methods are defined in `active_support/core_ext/date_time/calculations.rb`.
 
-The class `DateTime` is a subclass of `Date` so by loading `active_support/core_ext/date/calculations.rb` you inherit these methods and their aliases, except that they will always return datetimes:
-
-```ruby
-yesterday
-tomorrow
-beginning_of_week (at_beginning_of_week)
-end_of_week (at_end_of_week)
-monday
-sunday
-weeks_ago
-prev_week (last_week)
-next_week
-months_ago
-months_since
-beginning_of_month (at_beginning_of_month)
-end_of_month (at_end_of_month)
-prev_month (last_month)
-next_month
-beginning_of_quarter (at_beginning_of_quarter)
-end_of_quarter (at_end_of_quarter)
-beginning_of_year (at_beginning_of_year)
-end_of_year (at_end_of_year)
-years_ago
-years_since
-prev_year (last_year)
-next_year
-on_weekday?
-on_weekend?
-```
+The class `DateTime` is a subclass of `Date` so by loading `active_support/core_ext/date/calculations.rb` you inherit these methods and their aliases, except that they will always return datetimes.
 
 The following methods are reimplemented so you do **not** need to load `active_support/core_ext/date/calculations.rb` for these ones:
 
@@ -3520,8 +3453,6 @@ Extensions to `Time`
 
 NOTE: All the following methods are defined in `active_support/core_ext/time/calculations.rb`.
 
-Active Support adds to `Time` many of the methods available for `DateTime`:
-
 ```ruby
 past?
 today?
@@ -3533,6 +3464,8 @@ change
 advance
 ago
 since (in)
+prev_day
+next_day
 beginning_of_day (midnight, at_midnight, at_beginning_of_day)
 end_of_day
 beginning_of_hour (at_beginning_of_hour)
@@ -3548,15 +3481,17 @@ months_ago
 months_since
 beginning_of_month (at_beginning_of_month)
 end_of_month (at_end_of_month)
-prev_month (last_month)
+prev_month
 next_month
+last_month
 beginning_of_quarter (at_beginning_of_quarter)
 end_of_quarter (at_end_of_quarter)
 beginning_of_year (at_beginning_of_year)
 end_of_year (at_end_of_year)
 years_ago
 years_since
-prev_year (last_year)
+prev_year
+last_year
 next_year
 on_weekday?
 on_weekend?
@@ -3614,6 +3549,74 @@ now.all_year
 # => Fri, 01 Jan 2010 00:00:00 UTC +00:00..Fri, 31 Dec 2010 23:59:59 UTC +00:00
 ```
 
+#### `prev_day`, `next_day`
+
+In Ruby 1.9 `prev_day` and `next_day` return the date in the last or next day:
+
+```ruby
+d = Date.new(2010, 5, 8) # => Sat, 08 May 2010
+d.prev_day               # => Fri, 07 May 2010
+d.next_day               # => Sun, 09 May 2010
+```
+
+#### `prev_month`, `next_month`
+
+In Ruby 1.9 `prev_month` and `next_month` return the date with the same day in the last or next month:
+
+```ruby
+d = Date.new(2010, 5, 8) # => Sat, 08 May 2010
+d.prev_month             # => Thu, 08 Apr 2010
+d.next_month             # => Tue, 08 Jun 2010
+```
+
+If such a day does not exist, the last day of the corresponding month is returned:
+
+```ruby
+Date.new(2000, 5, 31).prev_month # => Sun, 30 Apr 2000
+Date.new(2000, 3, 31).prev_month # => Tue, 29 Feb 2000
+Date.new(2000, 5, 31).next_month # => Fri, 30 Jun 2000
+Date.new(2000, 1, 31).next_month # => Tue, 29 Feb 2000
+```
+
+#### `prev_year`, `next_year`
+
+In Ruby 1.9 `prev_year` and `next_year` return a date with the same day/month in the last or next year:
+
+```ruby
+d = Date.new(2010, 5, 8) # => Sat, 08 May 2010
+d.prev_year              # => Fri, 08 May 2009
+d.next_year              # => Sun, 08 May 2011
+```
+
+If date is the 29th of February of a leap year, you obtain the 28th:
+
+```ruby
+d = Date.new(2000, 2, 29) # => Tue, 29 Feb 2000
+d.prev_year               # => Sun, 28 Feb 1999
+d.next_year               # => Wed, 28 Feb 2001
+```
+
+#### `prev_quarter`, `next_quarter`
+
+`prev_quarter` and `next_quarter` return the date with the same day in the previous or next quarter:
+
+```ruby
+t = Time.local(2010, 5, 8) # => 2010-05-08 00:00:00 +0300
+t.prev_quarter             # => 2010-02-08 00:00:00 +0200
+t.next_quarter             # => 2010-08-08 00:00:00 +0300
+```
+
+If such a day does not exist, the last day of the corresponding month is returned:
+
+```ruby
+Time.local(2000, 7, 31).prev_quarter  # => 2000-04-30 00:00:00 +0300
+Time.local(2000, 5, 31).prev_quarter  # => 2000-02-29 00:00:00 +0200
+Time.local(2000, 10, 31).prev_quarter # => 2000-07-31 00:00:00 +0300
+Time.local(2000, 11, 31).next_quarter # => 2001-03-01 00:00:00 +0200
+```
+
+`prev_quarter` is aliased to `last_quarter`.
+
 ### Time Constructors
 
 Active Support defines `Time.current` to be `Time.zone.now` if there's a user time zone defined, with fallback to `Time.now`:
@@ -3637,7 +3640,7 @@ Durations can be added to and subtracted from time objects:
 now = Time.current
 # => Mon, 09 Aug 2010 23:20:05 UTC +00:00
 now + 1.year
-#  => Tue, 09 Aug 2011 23:21:11 UTC +00:00
+# => Tue, 09 Aug 2011 23:21:11 UTC +00:00
 now - 1.week
 # => Mon, 02 Aug 2010 23:21:11 UTC +00:00
 ```
@@ -3700,9 +3703,9 @@ Extensions to `NameError`
 
 Active Support adds `missing_name?` to `NameError`, which tests whether the exception was raised because of the name passed as argument.
 
-The name may be given as a symbol or string. A symbol is tested against the bare constant name, a string is against the fully-qualified constant name.
+The name may be given as a symbol or string. A symbol is tested against the bare constant name, a string is against the fully qualified constant name.
 
-TIP: A symbol can represent a fully-qualified constant name as in `:"ActiveRecord::Base"`, so the behavior for symbols is defined for convenience, not because it has to be that way technically.
+TIP: A symbol can represent a fully qualified constant name as in `:"ActiveRecord::Base"`, so the behavior for symbols is defined for convenience, not because it has to be that way technically.
 
 For example, when an action of `ArticlesController` is called Rails tries optimistically to use `ArticlesHelper`. It is OK that the helper module does not exist, so if an exception for that constant name is raised it should be silenced. But it could be the case that `articles_helper.rb` raises a `NameError` due to an actual unknown constant. That should be reraised. The method `missing_name?` provides a way to distinguish both cases:
 
diff --git a/guides/source/active_support_instrumentation.md b/guides/source/active_support_instrumentation.md
index 03af3cf819..11c4a8222a 100644
--- a/guides/source/active_support_instrumentation.md
+++ b/guides/source/active_support_instrumentation.md
@@ -197,6 +197,12 @@ INFO. Additional keys may be added by the caller.
 }
 ```
 
+### unpermitted_parameters.action_controller
+
+| Key     | Value            |
+| ------- | ---------------- |
+| `:keys` | Unpermitted keys |
+
 Action View
 -----------
 
@@ -226,17 +232,36 @@ Action View
 }
 ```
 
+### render_collection.action_view
+
+| Key           | Value                                 |
+| ------------- | ------------------------------------- |
+| `:identifier` | Full path to template                 |
+| `:count`      | Size of collection                    |
+| `:cache_hits` | Number of partials fetched from cache |
+
+`:cache_hits` is only included if the collection is rendered with `cached: true`.
+
+```ruby
+{
+  identifier: "/Users/adam/projects/notifications/app/views/posts/_post.html.erb",
+  count: 3,
+  cache_hits: 0
+}
+```
+
 Active Record
 ------------
 
 ### sql.active_record
 
-| Key              | Value                 |
-| ---------------- | --------------------- |
-| `:sql`           | SQL statement         |
-| `:name`          | Name of the operation |
-| `:connection_id` | `self.object_id`      |
-| `:binds`         | Bind parameters       |
+| Key              | Value                                    |
+| ---------------- | ---------------------------------------- |
+| `:sql`           | SQL statement                            |
+| `:name`          | Name of the operation                    |
+| `:connection_id` | `self.object_id`                         |
+| `:binds`         | Bind parameters                          |
+| `:cached`        | `true` is added when cached queries used |
 
 INFO. The adapters will add their own data as well.
 
@@ -285,7 +310,7 @@ Action Mailer
   mailer: "Notification",
   message_id: "4f5b5491f1774_181b23fc3d4434d38138e5@mba.local.mail",
   subject: "Rails Guides",
-  to: ["users@rails.com", "ddh@rails.com"],
+  to: ["users@rails.com", "dhh@rails.com"],
   from: ["me@rails.com"],
   date: Sat, 10 Mar 2012 14:18:09 +0100,
   mail: "..." # omitted for brevity
@@ -311,13 +336,29 @@ Action Mailer
   mailer: "Notification",
   message_id: "4f5b5491f1774_181b23fc3d4434d38138e5@mba.local.mail",
   subject: "Rails Guides",
-  to: ["users@rails.com", "ddh@rails.com"],
+  to: ["users@rails.com", "dhh@rails.com"],
   from: ["me@rails.com"],
   date: Sat, 10 Mar 2012 14:18:09 +0100,
   mail: "..." # omitted for brevity
 }
 ```
 
+### process.action_mailer
+
+| Key           | Value                    |
+| ------------- | ------------------------ |
+| `:mailer`     | Name of the mailer class |
+| `:action`     | The action               |
+| `:args`       | The arguments            |
+
+```ruby
+{
+  mailer: "Notification",
+  action: "welcome_email",
+  args: []
+}
+```
+
 Active Support
 --------------
 
@@ -431,6 +472,99 @@ Active Job
 | `:adapter`   | QueueAdapter object processing the job |
 | `:job`       | Job object                             |
 
+Action Cable
+------------
+
+### perform_action.action_cable
+
+| Key              | Value                     |
+| ---------------- | ------------------------- |
+| `:channel_class` | Name of the channel class |
+| `:action`        | The action                |
+| `:data`          | A hash of data            |
+
+### transmit.action_cable
+
+| Key              | Value                     |
+| ---------------- | ------------------------- |
+| `:channel_class` | Name of the channel class |
+| `:data`          | A hash of data            |
+| `:via`           | Via                       |
+
+### transmit_subscription_confirmation.action_cable
+
+| Key              | Value                     |
+| ---------------- | ------------------------- |
+| `:channel_class` | Name of the channel class |
+
+### transmit_subscription_rejection.action_cable
+
+| Key              | Value                     |
+| ---------------- | ------------------------- |
+| `:channel_class` | Name of the channel class |
+
+### broadcast.action_cable
+
+| Key             | Value                |
+| --------------- | -------------------- |
+| `:broadcasting` | A named broadcasting |
+| `:message`      | A hash of message    |
+| `:coder`        | The coder            |
+
+Active Storage
+--------------
+
+### service_upload.active_storage
+
+| Key          | Value                        |
+| ------------ | ---------------------------- |
+| `:key`       | Secure token                 |
+| `:service`   | Name of the service          |
+| `:checksum`  | Checksum to ensure integrity |
+
+### service_streaming_download.active_storage
+
+| Key          | Value               |
+| ------------ | ------------------- |
+| `:key`       | Secure token        |
+| `:service`   | Name of the service |
+
+### service_download.active_storage
+
+| Key          | Value               |
+| ------------ | ------------------- |
+| `:key`       | Secure token        |
+| `:service`   | Name of the service |
+
+### service_delete.active_storage
+
+| Key          | Value               |
+| ------------ | ------------------- |
+| `:key`       | Secure token        |
+| `:service`   | Name of the service |
+
+### service_delete_prefixed.active_storage
+
+| Key          | Value               |
+| ------------ | ------------------- |
+| `:prefix`    | Key prefix          |
+| `:service`   | Name of the service |
+
+### service_exist.active_storage
+
+| Key          | Value                       |
+| ------------ | --------------------------- |
+| `:key`       | Secure token                |
+| `:service`   | Name of the service         |
+| `:exist`     | File or blob exists or not  |
+
+### service_url.active_storage
+
+| Key          | Value               |
+| ------------ | ------------------- |
+| `:key`       | Secure token        |
+| `:service`   | Name of the service |
+| `:url`       | Generated url       |
 
 Railties
 --------
@@ -530,4 +664,4 @@ end
 ```
 
 You should follow Rails conventions when defining your own events. The format is: `event.library`.
-If you application is sending Tweets, you should create an event named `tweet.twitter`.
+If your application is sending Tweets, you should create an event named `tweet.twitter`.
diff --git a/guides/source/api_app.md b/guides/source/api_app.md
index f373d313cc..b4d90d31de 100644
--- a/guides/source/api_app.md
+++ b/guides/source/api_app.md
@@ -1,6 +1,5 @@
 **DO NOT READ THIS FILE ON GITHUB, GUIDES ARE PUBLISHED ON http://guides.rubyonrails.org.**
 
-
 Using Rails for API-only Applications
 =====================================
 
@@ -18,7 +17,7 @@ What is an API Application?
 
 Traditionally, when people said that they used Rails as an "API", they meant
 providing a programmatically accessible API alongside their web application.
-For example, GitHub provides [an API](http://developer.github.com) that you
+For example, GitHub provides [an API](https://developer.github.com) that you
 can use from your own custom clients.
 
 With the advent of client-side frameworks, more developers are using Rails to
@@ -66,9 +65,9 @@ Handled at the middleware layer:
   about the request environment, database queries, and basic performance
   information.
 - Security: Rails detects and thwarts [IP spoofing
-  attacks](http://en.wikipedia.org/wiki/IP_address_spoofing) and handles
+  attacks](https://en.wikipedia.org/wiki/IP_address_spoofing) and handles
   cryptographic signatures in a [timing
-  attack](http://en.wikipedia.org/wiki/Timing_attack) aware way. Don't know what
+  attack](https://en.wikipedia.org/wiki/Timing_attack) aware way. Don't know what
   an IP spoofing attack or a timing attack is? Exactly.
 - Parameter Parsing: Want to specify your parameters as JSON instead of as a
   URL-encoded String? No problem. Rails will decode the JSON for you and make
@@ -94,7 +93,7 @@ Handled at the Action Pack layer:
   means not having to spend time thinking about how to model your API in terms
   of HTTP.
 - URL Generation: The flip side of routing is URL generation. A good API based
-  on HTTP includes URLs (see [the GitHub Gist API](http://developer.github.com/v3/gists/)
+  on HTTP includes URLs (see [the GitHub Gist API](https://developer.github.com/v3/gists/)
   for an example).
 - Header and Redirection Responses: `head :no_content` and
   `redirect_to user_url(current_user)` come in handy. Sure, you could manually
@@ -206,10 +205,10 @@ An API application comes with the following middleware by default:
 - `ActiveSupport::Cache::Strategy::LocalCache::Middleware`
 - `Rack::Runtime`
 - `ActionDispatch::RequestId`
+- `ActionDispatch::RemoteIp`
 - `Rails::Rack::Logger`
 - `ActionDispatch::ShowExceptions`
 - `ActionDispatch::DebugExceptions`
-- `ActionDispatch::RemoteIp`
 - `ActionDispatch::Reloader`
 - `ActionDispatch::Callbacks`
 - `ActiveRecord::Migration::CheckPending`
@@ -360,7 +359,7 @@ middleware set, you can remove it with:
 config.middleware.delete ::Rack::Sendfile
 ```
 
-Keep in mind that removing these middleware will remove support for certain
+Keep in mind that removing these middlewares will remove support for certain
 features in Action Controller.
 
 Choosing Controller Modules
@@ -385,8 +384,9 @@ controller modules by default:
   hooks defined by Action Controller (see [the instrumentation
   guide](active_support_instrumentation.html#action-controller) for
 more information regarding this).
-- `ActionController::ParamsWrapper`: Wraps the parameters hash into a nested hash, 
+- `ActionController::ParamsWrapper`: Wraps the parameters hash into a nested hash,
   so that you don't have to specify root elements sending POST requests for instance.
+- `ActionController::Head`: Support for returning a response with no content, only headers
 
 Other plugins may add additional modules. You can get a list of all modules
 included into `ActionController::API` in the rails console:
@@ -394,12 +394,12 @@ included into `ActionController::API` in the rails console:
 ```bash
 $ bin/rails c
 >> ActionController::API.ancestors - ActionController::Metal.ancestors
-=> [ActionController::API, 
-    ActiveRecord::Railties::ControllerRuntime, 
-    ActionDispatch::Routing::RouteSet::MountedHelpers, 
-    ActionController::ParamsWrapper, 
-    ... , 
-    AbstractController::Rendering, 
+=> [ActionController::API,
+    ActiveRecord::Railties::ControllerRuntime,
+    ActionDispatch::Routing::RouteSet::MountedHelpers,
+    ActionController::ParamsWrapper,
+    ... ,
+    AbstractController::Rendering,
     ActionView::ViewPaths]
 ```
 
@@ -413,8 +413,10 @@ Some common modules you might want to add:
 
 - `AbstractController::Translation`: Support for the `l` and `t` localization
   and translation methods.
-- `ActionController::HttpAuthentication::Basic` (or `Digest` or `Token`): Support
-  for basic, digest or token HTTP authentication.
+- Support for basic, digest or token HTTP authentication:
+  * `ActionController::HttpAuthentication::Basic::ControllerMethods`,
+  * `ActionController::HttpAuthentication::Digest::ControllerMethods`,
+  * `ActionController::HttpAuthentication::Token::ControllerMethods`
 - `ActionView::Layouts`: Support for layouts when rendering.
 - `ActionController::MimeResponds`: Support for `respond_to`.
 - `ActionController::Cookies`: Support for `cookies`, which includes
diff --git a/guides/source/api_documentation_guidelines.md b/guides/source/api_documentation_guidelines.md
index 34b9c0d2ca..10b89433e7 100644
--- a/guides/source/api_documentation_guidelines.md
+++ b/guides/source/api_documentation_guidelines.md
@@ -16,7 +16,7 @@ RDoc
 ----
 
 The [Rails API documentation](http://api.rubyonrails.org) is generated with
-[RDoc](http://docs.seattlerb.org/rdoc/). To generate it, make sure you are
+[RDoc](https://ruby.github.io/rdoc/). To generate it, make sure you are
 in the rails root directory, run `bundle install` and execute:
 
 ```bash
@@ -26,9 +26,9 @@ in the rails root directory, run `bundle install` and execute:
 Resulting HTML files can be found in the ./doc/rdoc directory.
 
 Please consult the RDoc documentation for help with the
-[markup](http://docs.seattlerb.org/rdoc/RDoc/Markup.html),
+[markup](https://ruby.github.io/rdoc/RDoc/Markup.html),
 and also take into account these [additional
-directives](http://docs.seattlerb.org/rdoc/RDoc/Parser/Ruby.html).
+directives](https://ruby.github.io/rdoc/RDoc/Parser/Ruby.html).
 
 Wording
 -------
@@ -82,12 +82,12 @@ used. Instead of:
 English
 -------
 
-Please use American English (*color*, *center*, *modularize*, etc). See [a list of American and British English spelling differences here](http://en.wikipedia.org/wiki/American_and_British_English_spelling_differences).
+Please use American English (*color*, *center*, *modularize*, etc). See [a list of American and British English spelling differences here](https://en.wikipedia.org/wiki/American_and_British_English_spelling_differences).
 
 Oxford Comma
 ------------
 
-Please use the [Oxford comma](http://en.wikipedia.org/wiki/Serial_comma)
+Please use the [Oxford comma](https://en.wikipedia.org/wiki/Serial_comma)
 ("red, white, and blue", instead of "red, white and blue").
 
 Example Code
@@ -281,7 +281,7 @@ Methods created with `(module|class)_eval(STRING)` have a comment by their side
 
 ```ruby
 for severity in Severity.constants
-  class_eval <<-EOT, __FILE__, __LINE__
+  class_eval <<-EOT, __FILE__, __LINE__ + 1
     def #{severity.downcase}(message = nil, progname = nil, &block)  # def debug(message = nil, progname = nil, &block)
       add(#{severity}, message, progname, &block)                    #   add(DEBUG, message, progname, &block)
     end                                                              # end
@@ -333,10 +333,6 @@ As a contributor, it's important to think about whether this API is meant for en
 
 A class or module is marked with `:nodoc:` to indicate that all methods are internal API and should never be used directly.
 
-If you come across an existing `:nodoc:` you should tread lightly. Consider asking someone from the core team or author of the code before removing it. This should almost always happen through a pull request instead of the docrails project.
-
-A `:nodoc:` should never be added simply because a method or class is missing documentation. There may be an instance where an internal public method wasn't given a `:nodoc:` by mistake, for example when switching a method from private to public visibility. When this happens it should be discussed over a PR on a case-by-case basis and never committed directly to docrails.
-
 To summarize, the Rails team uses `:nodoc:` to mark publicly visible methods and classes for internal use; changes to the visibility of API should be considered carefully and discussed over a pull request first.
 
 Regarding the Rails Stack
@@ -354,7 +350,7 @@ into account, one such example is
 
 ```ruby
 # image_tag("icon.png")
-#   # => <img alt="Icon" src="/assets/icon.png" />
+#   # => <img src="/assets/icon.png" />
 ```
 
 Although the default behavior for `#image_tag` is to always return
diff --git a/guides/source/asset_pipeline.md b/guides/source/asset_pipeline.md
index e6631a513c..e6d5aed135 100644
--- a/guides/source/asset_pipeline.md
+++ b/guides/source/asset_pipeline.md
@@ -35,7 +35,7 @@ rails new appname --skip-sprockets
 ```
 
 Rails automatically adds the `sass-rails`, `coffee-rails` and `uglifier`
-gems to your Gemfile, which are used by Sprockets for asset compression:
+gems to your `Gemfile`, which are used by Sprockets for asset compression:
 
 ```ruby
 gem 'sass-rails'
@@ -44,8 +44,8 @@ gem 'coffee-rails'
 ```
 
 Using the `--skip-sprockets` option will prevent Rails from adding
-them to your Gemfile, so if you later want to enable
-the asset pipeline you will have to add those gems to your Gemfile. Also,
+them to your `Gemfile`, so if you later want to enable
+the asset pipeline you will have to add those gems to your `Gemfile`. Also,
 creating an application with the `--skip-sprockets` option will generate
 a slightly different `config/application.rb` file, with a require statement
 for the sprockets railtie that is commented-out. You will have to remove
@@ -65,7 +65,7 @@ config.assets.js_compressor = :uglifier
 ```
 
 NOTE: The `sass-rails` gem is automatically used for CSS compression if included
-in the Gemfile and no `config.assets.css_compressor` option is set.
+in the `Gemfile` and no `config.assets.css_compressor` option is set.
 
 
 ### Main Features
@@ -78,9 +78,9 @@ requests can mean faster loading for your application.
 Sprockets concatenates all JavaScript files into one master `.js` file and all
 CSS files into one master `.css` file. As you'll learn later in this guide, you
 can customize this strategy to group files any way you like. In production,
-Rails inserts an MD5 fingerprint into each filename so that the file is cached
-by the web browser. You can invalidate the cache by altering this fingerprint,
-which happens automatically whenever you change the file contents.
+Rails inserts an SHA256 fingerprint into each filename so that the file is
+cached by the web browser. You can invalidate the cache by altering this
+fingerprint, which happens automatically whenever you change the file contents.
 
 The second feature of the asset pipeline is asset minification or compression.
 For CSS files, this is done by removing whitespace and comments. For JavaScript,
@@ -106,7 +106,7 @@ or in web browsers) to keep their own copy of the content. When the content is
 updated, the fingerprint will change. This will cause the remote clients to
 request a new copy of the content. This is generally known as _cache busting_.
 
-The technique sprockets uses for fingerprinting is to insert a hash of the
+The technique Sprockets uses for fingerprinting is to insert a hash of the
 content into the name, usually at the end. For example a CSS file `global.css`
 
 ```
@@ -154,7 +154,7 @@ environments. You can enable or disable it in your configuration through the
 
 More reading:
 
-* [Optimize caching](http://code.google.com/speed/page-speed/docs/caching.html)
+* [Optimize caching](https://developers.google.com/speed/docs/insights/LeverageBrowserCaching)
 * [Revving Filenames: don't use querystring](http://www.stevesouders.com/blog/2008/08/23/revving-filenames-dont-use-querystring/)
 
 
@@ -181,7 +181,7 @@ When you generate a scaffold or a controller, Rails also generates a JavaScript
 file (or CoffeeScript file if the `coffee-rails` gem is in the `Gemfile`) and a
 Cascading Style Sheet file (or SCSS file if `sass-rails` is in the `Gemfile`)
 for that controller. Additionally, when generating a scaffold, Rails generates
-the file scaffolds.css (or scaffolds.scss if `sass-rails` is in the
+the file `scaffolds.css` (or `scaffolds.scss` if `sass-rails` is in the
 `Gemfile`.)
 
 For example, if you generate a `ProjectsController`, Rails will also add a new
@@ -202,12 +202,12 @@ will result in your assets being included more than once.
 
 WARNING: When using asset precompilation, you will need to ensure that your
 controller assets will be precompiled when loading them on a per page basis. By
-default .coffee and .scss files will not be precompiled on their own. See
+default `.coffee` and `.scss` files will not be precompiled on their own. See
 [Precompiling Assets](#precompiling-assets) for more information on how
 precompiling works.
 
 NOTE: You must have an ExecJS supported runtime in order to use CoffeeScript.
-If you are using Mac OS X or Windows, you have a JavaScript runtime installed in
+If you are using macOS or Windows, you have a JavaScript runtime installed in
 your operating system. Check [ExecJS](https://github.com/rails/execjs#readme) documentation to know all supported JavaScript runtimes.
 
 You can also disable generation of controller specific asset files by adding the
@@ -283,10 +283,10 @@ You can view the search path by inspecting
 `Rails.application.config.assets.paths` in the Rails console.
 
 Besides the standard `assets/*` paths, additional (fully qualified) paths can be
-added to the pipeline in `config/application.rb`. For example:
+added to the pipeline in `config/initializers/assets.rb`. For example:
 
 ```ruby
-config.assets.paths << Rails.root.join("lib", "videoplayer", "flash")
+Rails.application.config.assets.paths << Rails.root.join("lib", "videoplayer", "flash")
 ```
 
 Paths are traversed in the order they occur in the search path. By default,
@@ -335,7 +335,7 @@ an asset has been updated and if so loads it into the page:
 <%= javascript_include_tag "application", "data-turbolinks-track" => "reload" %>
 ```
 
-In regular views you can access images in the `public/assets/images` directory
+In regular views you can access images in the `app/assets/images` directory
 like this:
 
 ```erb
@@ -346,9 +346,9 @@ Provided that the pipeline is enabled within your application (and not disabled
 in the current environment context), this file is served by Sprockets. If a file
 exists at `public/assets/rails.png` it is served by the web server.
 
-Alternatively, a request for a file with an MD5 hash such as
-`public/assets/rails-af27b6a414e6da00003503148be9b409.png` is treated the same
-way. How these hashes are generated is covered in the [In
+Alternatively, a request for a file with an SHA256 hash such as
+`public/assets/rails-f90d8a84c707a8dc923fca1ca1895ae8ed0a09237f6992015fef1e11be77c023.png`
+is treated the same way. How these hashes are generated is covered in the [In
 Production](#in-production) section later on in this guide.
 
 Sprockets will also look through the paths specified in `config.assets.paths`,
@@ -383,7 +383,7 @@ it would make sense to have an image in one of the asset load paths, such as
 already available in `public/assets` as a fingerprinted file, then that path is
 referenced.
 
-If you want to use a [data URI](http://en.wikipedia.org/wiki/Data_URI_scheme) -
+If you want to use a [data URI](https://en.wikipedia.org/wiki/Data_URI_scheme) -
 a method of embedding the image data directly into the CSS file - you can use
 the `asset_data_uri` helper.
 
@@ -447,15 +447,15 @@ For example, a new Rails application includes a default
 
 ```js
 // ...
-//= require jquery
-//= require jquery_ujs
+//= require rails-ujs
+//= require turbolinks
 //= require_tree .
 ```
 
 In JavaScript files, Sprockets directives begin with `//=`. In the above case,
 the file is using the `require` and the `require_tree` directives. The `require`
 directive is used to tell Sprockets the files you wish to require. Here, you are
-requiring the files `jquery.js` and `jquery_ujs.js` that are available somewhere
+requiring the files `rails-ujs.js` and `turbolinks.js` that are available somewhere
 in the search path for Sprockets. You need not supply the extensions explicitly.
 Sprockets assumes you are requiring a `.js` file when done from within a `.js`
 file.
@@ -485,7 +485,7 @@ which contains these lines:
 
 Rails creates both `app/assets/javascripts/application.js` and
 `app/assets/stylesheets/application.css` regardless of whether the
---skip-sprockets option is used when creating a new rails application. This is
+--skip-sprockets option is used when creating a new Rails application. This is
 so you can easily add asset pipelining later if you like.
 
 The directives that work in JavaScript files also work in stylesheets
@@ -572,19 +572,18 @@ would generate this HTML:
 
 The `body` param is required by Sprockets.
 
-### Runtime Error Checking
+### Raise an Error When an Asset is Not Found
 
-By default the asset pipeline will check for potential errors in development mode during
-runtime. To disable this behavior you can set:
+If you are using sprockets-rails >= 3.2.0 you can configure what happens
+when an asset lookup is performed and nothing is found. If you turn off "asset fallback"
+then an error will be raised when an asset cannot be found.
 
 ```ruby
-config.assets.raise_runtime_errors = false
+config.assets.unknown_asset_fallback = false
 ```
 
-When this option is true, the asset pipeline will check if all the assets loaded
-in your application are included in the `config.assets.precompile` list.
-If `config.assets.digest` is also true, the asset pipeline will require that
-all requests for assets include digests.
+If "asset fallback" is enabled then when an asset cannot be found the path will be
+output instead and no error raised. The asset fallback behavior is enabled by default.
 
 ### Turning Digests Off
 
@@ -641,7 +640,7 @@ In the production environment Sprockets uses the fingerprinting scheme outlined
 above. By default Rails assumes assets have been precompiled and will be
 served as static assets by your web server.
 
-During the precompilation phase an MD5 is generated from the contents of the
+During the precompilation phase an SHA256 is generated from the contents of the
 compiled files, and inserted into the filenames as they are written to disk.
 These fingerprinted names are used by the Rails helpers in place of the manifest
 name.
@@ -724,28 +723,30 @@ If you have other manifests or individual stylesheets and JavaScript files to
 include, you can add them to the `precompile` array in `config/initializers/assets.rb`:
 
 ```ruby
-Rails.application.config.assets.precompile += ['admin.js', 'admin.css', 'swfObject.js']
+Rails.application.config.assets.precompile += %w( admin.js admin.css )
 ```
 
-NOTE. Always specify an expected compiled filename that ends with .js or .css,
+NOTE. Always specify an expected compiled filename that ends with `.js` or `.css`,
 even if you want to add Sass or CoffeeScript files to the precompile array.
 
-The task also generates a `manifest-md5hash.json` that contains a list with
-all your assets and their respective fingerprints. This is used by the Rails
-helper methods to avoid handing the mapping requests back to Sprockets. A
-typical manifest file looks like:
+The task also generates a `.sprockets-manifest-md5hash.json` (where `md5hash` is
+an MD5 hash) that contains a list with all your assets and their respective
+fingerprints. This is used by the Rails helper methods to avoid handing the
+mapping requests back to Sprockets. A typical manifest file looks like:
 
 ```ruby
-{"files":{"application-723d1be6cc741a3aabb1cec24276d681.js":{"logical_path":"application.js","mtime":"2013-07-26T22:55:03-07:00","size":302506,
-"digest":"723d1be6cc741a3aabb1cec24276d681"},"application-12b3c7dd74d2e9df37e7cbb1efa76a6d.css":{"logical_path":"application.css","mtime":"2013-07-26T22:54:54-07:00","size":1560,
-"digest":"12b3c7dd74d2e9df37e7cbb1efa76a6d"},"application-1c5752789588ac18d7e1a50b1f0fd4c2.css":{"logical_path":"application.css","mtime":"2013-07-26T22:56:17-07:00","size":1591,
-"digest":"1c5752789588ac18d7e1a50b1f0fd4c2"},"favicon-a9c641bf2b81f0476e876f7c5e375969.ico":{"logical_path":"favicon.ico","mtime":"2013-07-26T23:00:10-07:00","size":1406,
-"digest":"a9c641bf2b81f0476e876f7c5e375969"},"my_image-231a680f23887d9dd70710ea5efd3c62.png":{"logical_path":"my_image.png","mtime":"2013-07-26T23:00:27-07:00","size":6646,
-"digest":"231a680f23887d9dd70710ea5efd3c62"}},"assets":{"application.js":
-"application-723d1be6cc741a3aabb1cec24276d681.js","application.css":
-"application-1c5752789588ac18d7e1a50b1f0fd4c2.css",
-"favicon.ico":"favicona9c641bf2b81f0476e876f7c5e375969.ico","my_image.png":
-"my_image-231a680f23887d9dd70710ea5efd3c62.png"}}
+{"files":{"application-aee4be71f1288037ae78b997df388332edfd246471b533dcedaa8f9fe156442b.js":{"logical_path":"application.js","mtime":"2016-12-23T20:12:03-05:00","size":412383,
+"digest":"aee4be71f1288037ae78b997df388332edfd246471b533dcedaa8f9fe156442b","integrity":"sha256-ruS+cfEogDeueLmX3ziDMu39JGRxtTPc7aqPn+FWRCs="},
+"application-86a292b5070793c37e2c0e5f39f73bb387644eaeada7f96e6fc040a028b16c18.css":{"logical_path":"application.css","mtime":"2016-12-23T19:12:20-05:00","size":2994,
+"digest":"86a292b5070793c37e2c0e5f39f73bb387644eaeada7f96e6fc040a028b16c18","integrity":"sha256-hqKStQcHk8N+LA5fOfc7s4dkTq6tp/lub8BAoCixbBg="},
+"favicon-8d2387b8d4d32cecd93fa3900df0e9ff89d01aacd84f50e780c17c9f6b3d0eda.ico":{"logical_path":"favicon.ico","mtime":"2016-12-23T20:11:00-05:00","size":8629,
+"digest":"8d2387b8d4d32cecd93fa3900df0e9ff89d01aacd84f50e780c17c9f6b3d0eda","integrity":"sha256-jSOHuNTTLOzZP6OQDfDp/4nQGqzYT1DngMF8n2s9Dto="},
+"my_image-f4028156fd7eca03584d5f2fc0470df1e0dbc7369eaae638b2ff033f988ec493.png":{"logical_path":"my_image.png","mtime":"2016-12-23T20:10:54-05:00","size":23414,
+"digest":"f4028156fd7eca03584d5f2fc0470df1e0dbc7369eaae638b2ff033f988ec493","integrity":"sha256-9AKBVv1+ygNYTV8vwEcN8eDbxzaequY4sv8DP5iOxJM="}},
+"assets":{"application.js":"application-aee4be71f1288037ae78b997df388332edfd246471b533dcedaa8f9fe156442b.js",
+"application.css":"application-86a292b5070793c37e2c0e5f39f73bb387644eaeada7f96e6fc040a028b16c18.css",
+"favicon.ico":"favicon-8d2387b8d4d32cecd93fa3900df0e9ff89d01aacd84f50e780c17c9f6b3d0eda.ico",
+"my_image.png":"my_image-f4028156fd7eca03584d5f2fc0470df1e0dbc7369eaae638b2ff033f988ec493.png"}}
 ```
 
 The default location for the manifest is the root of the location specified in
@@ -837,7 +838,7 @@ config.assets.compile = true
 
 On the first request the assets are compiled and cached as outlined in
 development above, and the manifest names used in the helpers are altered to
-include the MD5 hash.
+include the SHA256 hash.
 
 Sprockets also sets the `Cache-Control` HTTP header to `max-age=31536000`. This
 signals all caches between your server and the client browser that this content
@@ -849,18 +850,18 @@ This mode uses more memory, performs more poorly than the default and is not
 recommended.
 
 If you are deploying a production application to a system without any
-pre-existing JavaScript runtimes, you may want to add one to your Gemfile:
+pre-existing JavaScript runtimes, you may want to add one to your `Gemfile`:
 
 ```ruby
 group :production do
-  gem 'therubyracer'
+  gem 'mini_racer'
 end
 ```
 
 ### CDNs
 
 CDN stands for [Content Delivery
-Network](http://en.wikipedia.org/wiki/Content_delivery_network), they are
+Network](https://en.wikipedia.org/wiki/Content_delivery_network), they are
 primarily designed to cache assets all over the world so that when a browser
 requests the asset, a cached copy will be geographically close to that browser.
 If you are serving assets directly from your Rails server in production, the
@@ -908,7 +909,7 @@ domain, you do not need to specify a protocol or "scheme" such as `http://` or
 that is generated will match how the webpage is accessed by default.
 
 You can also set this value through an [environment
-variable](http://en.wikipedia.org/wiki/Environment_variable) to make running a
+variable](https://en.wikipedia.org/wiki/Environment_variable) to make running a
 staging copy of your site easier:
 
 ```
@@ -1024,7 +1025,7 @@ to tell our CDN (and browser) that the asset is "public", that means any cache
 can store the request. Also we commonly want to set `max-age` which is how long
 the cache will store the object before invalidating the cache. The `max-age`
 value is set to seconds with a maximum possible value of `31536000` which is one
-year. You can do this in your rails application by setting
+year. You can do this in your Rails application by setting
 
 ```
 config.public_file_server.headers = {
@@ -1068,7 +1069,7 @@ Customizing the Pipeline
 ### CSS Compression
 
 One of the options for compressing CSS is YUI. The [YUI CSS
-compressor](http://yui.github.io/yuicompressor/css.html) provides
+compressor](https://yui.github.io/yuicompressor/css.html) provides
 minification.
 
 The following line enables YUI compression, and requires the `yui-compressor`
@@ -1089,7 +1090,7 @@ Possible options for JavaScript compression are `:closure`, `:uglifier` and
 `:yui`. These require the use of the `closure-compiler`, `uglifier` or
 `yui-compressor` gems, respectively.
 
-The default Gemfile includes [uglifier](https://github.com/lautis/uglifier).
+The default `Gemfile` includes [uglifier](https://github.com/lautis/uglifier).
 This gem wraps [UglifyJS](https://github.com/mishoo/UglifyJS) (written for
 NodeJS) in Ruby. It compresses your code by removing white space and comments,
 shortening local variable names, and performing other micro-optimizations such
@@ -1102,16 +1103,16 @@ config.assets.js_compressor = :uglifier
 ```
 
 NOTE: You will need an [ExecJS](https://github.com/rails/execjs#readme)
-supported runtime in order to use `uglifier`. If you are using Mac OS X or
+supported runtime in order to use `uglifier`. If you are using macOS or
 Windows you have a JavaScript runtime installed in your operating system.
 
 
 
 ### Serving GZipped version of assets
 
-By default, gzipped version of compiled assets will be generated, along 
-with the non-gzipped version of assets. Gzipped assets help reduce the transmission of 
-data over the wire. You can configure this by setting the `gzip` flag.
+By default, gzipped version of compiled assets will be generated, along with
+the non-gzipped version of assets. Gzipped assets help reduce the transmission
+of data over the wire. You can configure this by setting the `gzip` flag.
 
 ```ruby
 config.assets.gzip = false # disable gzipped assets generation
@@ -1214,35 +1215,25 @@ Sprockets.
 Making Your Library or Gem a Pre-Processor
 ------------------------------------------
 
-As Sprockets uses [Tilt](https://github.com/rtomayko/tilt) as a generic
-interface to different templating engines, your gem should just implement the
-Tilt template protocol. Normally, you would subclass `Tilt::Template` and
-reimplement the `prepare` method, which initializes your template, and the
-`evaluate` method, which returns the processed source. The original source is
-stored in `data`. Have a look at
-[`Tilt::Template`](https://github.com/rtomayko/tilt/blob/master/lib/tilt/template.rb)
-sources to learn more.
+Sprockets uses Processors, Transformers, Compressors, and Exporters to extend
+Sprockets functionality. Have a look at
+[Extending Sprockets](https://github.com/rails/sprockets/blob/master/guides/extending_sprockets.md)
+to learn more. Here we registered a preprocessor to add a comment to the end
+of text/css (`.css`) files.
 
 ```ruby
-module BangBang
-  class Template < ::Tilt::Template
-    def prepare
-      # Do any initialization here
-    end
-
-    # Adds a "!" to original template.
-    def evaluate(scope, locals, &block)
-      "#{data}!"
-    end
+module AddComment
+  def self.call(input)
+    { data: input[:data] + "/* Hello From my sprockets extension */" }
   end
 end
 ```
 
-Now that you have a `Template` class, it's time to associate it with an
-extension for template files:
+Now that you have a module that modifies the input data, it's time to register
+it as a preprocessor for your mime type.
 
 ```ruby
-Sprockets.register_engine '.bang', BangBang::Template
+Sprockets.register_preprocessor 'text/css', AddComment
 ```
 
 Upgrading from Old Versions of Rails
@@ -1291,7 +1282,7 @@ config.assets.digest = true
 
 # Precompile additional assets (application.js, application.css, and all
 # non-JS/CSS are already added)
-# config.assets.precompile += %w( search.js )
+# config.assets.precompile += %w( admin.js admin.css )
 ```
 
 Rails 4 and above no longer set default config values for Sprockets in `test.rb`, so
diff --git a/guides/source/association_basics.md b/guides/source/association_basics.md
index 3993fdb1dd..b5e236b790 100644
--- a/guides/source/association_basics.md
+++ b/guides/source/association_basics.md
@@ -154,7 +154,7 @@ case, the column definition might look like this:
 
 ```ruby
 create_table :accounts do |t|
-  t.belongs_to :supplier, index: true, unique: true, foreign_key: true
+  t.belongs_to :supplier, index: { unique: true }, foreign_key: true
   # ...
 end
 ```
@@ -387,7 +387,7 @@ The corresponding migration might look like this:
 class CreateSuppliers < ActiveRecord::Migration[5.0]
   def change
     create_table :suppliers do |t|
-      t.string  :name
+      t.string :name
       t.timestamps
     end
 
@@ -550,8 +550,8 @@ But what if you want to reload the cache, because data might have been changed b
 ```ruby
 author.books                 # retrieves books from the database
 author.books.size            # uses the cached copy of books
-author.books.reload.empty?    # discards the cached copy of books
-                                # and goes back to the database
+author.books.reload.empty?   # discards the cached copy of books
+                             # and goes back to the database
 ```
 
 ### Avoiding Name Collisions
@@ -582,14 +582,30 @@ class CreateBooks < ActiveRecord::Migration[5.0]
       t.string   :book_number
       t.integer  :author_id
     end
-
-    add_index :books, :author_id
   end
 end
 ```
 
 If you create an association some time after you build the underlying model, you need to remember to create an `add_column` migration to provide the necessary foreign key.
 
+It's a good practice to add an index on the foreign key to improve queries
+performance and a foreign key constraint to ensure referential data integrity:
+
+```ruby
+class CreateBooks < ActiveRecord::Migration[5.0]
+  def change
+    create_table :books do |t|
+      t.datetime :published_at
+      t.string   :book_number
+      t.integer  :author_id
+    end
+
+    add_index :books, :author_id
+    add_foreign_key :books, :authors
+  end
+end
+```
+
 #### Creating Join Tables for `has_and_belongs_to_many` Associations
 
 If you create a `has_and_belongs_to_many` association, you need to explicitly create the joining table. Unless the name of the join table is explicitly specified by using the `:join_table` option, Active Record creates the name by using the lexical book of the class names. So a join between author and book models will give the default join table name of "authors_books" because "a" outranks "b" in lexical ordering.
@@ -647,11 +663,11 @@ By default, associations look for objects only within the current module's scope
 module MyApplication
   module Business
     class Supplier < ApplicationRecord
-       has_one :account
+      has_one :account
     end
 
     class Account < ApplicationRecord
-       belongs_to :supplier
+      belongs_to :supplier
     end
   end
 end
@@ -663,13 +679,13 @@ This will work fine, because both the `Supplier` and the `Account` class are def
 module MyApplication
   module Business
     class Supplier < ApplicationRecord
-       has_one :account
+      has_one :account
     end
   end
 
   module Billing
     class Account < ApplicationRecord
-       belongs_to :supplier
+      belongs_to :supplier
     end
   end
 end
@@ -681,14 +697,14 @@ To associate a model with a model in a different namespace, you must specify the
 module MyApplication
   module Business
     class Supplier < ApplicationRecord
-       has_one :account,
+      has_one :account,
         class_name: "MyApplication::Billing::Account"
     end
   end
 
   module Billing
     class Account < ApplicationRecord
-       belongs_to :supplier,
+      belongs_to :supplier,
         class_name: "MyApplication::Business::Supplier"
     end
   end
@@ -709,55 +725,73 @@ class Book < ApplicationRecord
 end
 ```
 
-By default, Active Record doesn't know about the connection between these associations. This can lead to two copies of an object getting out of sync:
+Active Record will attempt to automatically identify that these two models share a bi-directional association based on the association name. In this way, Active Record will only load one copy of the `Author` object, making your application more efficient and preventing inconsistent data:
 
 ```ruby
 a = Author.first
 b = a.books.first
 a.first_name == b.author.first_name # => true
-a.first_name = 'Manny'
-a.first_name == b.author.first_name # => false
+a.first_name = 'David'
+a.first_name == b.author.first_name # => true
 ```
 
-This happens because `a` and `b.author` are two different in-memory representations of the same data, and neither one is automatically refreshed from changes to the other. Active Record provides the `:inverse_of` option so that you can inform it of these relations:
+Active Record supports automatic identification for most associations with standard names. However, Active Record will not automatically identify bi-directional associations that contain any of the following options:
+
+* `:conditions`
+* `:through`
+* `:polymorphic`
+* `:class_name`
+* `:foreign_key`
+
+For example, consider the following model declarations:
 
 ```ruby
 class Author < ApplicationRecord
-  has_many :books, inverse_of: :author
+  has_many :books
 end
 
 class Book < ApplicationRecord
-  belongs_to :author, inverse_of: :books
+  belongs_to :writer, class_name: 'Author', foreign_key: 'author_id'
 end
 ```
 
-With these changes, Active Record will only load one copy of the author object, preventing inconsistencies and making your application more efficient:
+Active Record will no longer automatically recognize the bi-directional association:
 
 ```ruby
 a = Author.first
 b = a.books.first
-a.first_name == b.author.first_name # => true
-a.first_name = 'Manny'
-a.first_name == b.author.first_name # => true
+a.first_name == b.writer.first_name # => true
+a.first_name = 'David'
+a.first_name == b.writer.first_name # => false
+```
+
+Active Record provides the `:inverse_of` option so you can explicitly declare bi-directional associations:
+
+```ruby
+class Author < ApplicationRecord
+  has_many :books, inverse_of: 'writer'
+end
+
+class Book < ApplicationRecord
+  belongs_to :writer, class_name: 'Author', foreign_key: 'author_id'
+end
 ```
 
-There are a few limitations to `inverse_of` support:
+By including the `:inverse_of` option in the `has_many` association declaration, Active Record will now recognize the bi-directional association:
+
+```ruby
+a = Author.first
+b = a.books.first
+a.first_name == b.writer.first_name # => true
+a.first_name = 'David'
+a.first_name == b.writer.first_name # => true
+```
+
+There are a few limitations to `:inverse_of` support:
 
 * They do not work with `:through` associations.
 * They do not work with `:polymorphic` associations.
 * They do not work with `:as` associations.
-* For `belongs_to` associations, `has_many` inverse associations are ignored.
-
-Every association will attempt to automatically find the inverse association
-and set the `:inverse_of` option heuristically (based on the association name).
-Most associations with standard names will be supported. However, associations
-that contain the following options will not have their inverses set
-automatically:
-
-* `:conditions`
-* `:through`
-* `:polymorphic`
-* `:foreign_key`
 
 Detailed Association Reference
 ------------------------------
@@ -777,6 +811,7 @@ When you declare a `belongs_to` association, the declaring class automatically g
 * `build_association(attributes = {})`
 * `create_association(attributes = {})`
 * `create_association!(attributes = {})`
+* `reload_association`
 
 In all of these methods, `association` is replaced with the symbol passed as the first argument to `belongs_to`. For example, given the declaration:
 
@@ -794,6 +829,7 @@ author=
 build_author
 create_author
 create_author!
+reload_author
 ```
 
 NOTE: When initializing a new `has_one` or `belongs_to` association you must use the `build_` prefix to build the association, rather than the `association.build` method that would be used for `has_many` or `has_and_belongs_to_many` associations. To create one, use the `create_` prefix.
@@ -806,10 +842,10 @@ The `association` method returns the associated object, if any. If no associated
 @author = @book.author
 ```
 
-If the associated object has already been retrieved from the database for this object, the cached version will be returned. To override this behavior (and force a database read), call `#reload` on the parent object.
+If the associated object has already been retrieved from the database for this object, the cached version will be returned. To override this behavior (and force a database read), call `#reload_association` on the parent object.
 
 ```ruby
-@author = @book.reload.author
+@author = @book.reload_author
 ```
 
 ##### `association=(associate)`
@@ -870,7 +906,7 @@ The `belongs_to` association supports these options:
 
 ##### `:autosave`
 
-If you set the `:autosave` option to `true`, Rails will save any loaded members and destroy members that are marked for destruction whenever you save the parent object.
+If you set the `:autosave` option to `true`, Rails will save any loaded association members and destroy members that are marked for destruction whenever you save the parent object. Setting `:autosave` to `false` is not the same as not setting the `:autosave` option. If the `:autosave` option is not present, then new associated objects will be saved, but updated associated objects will not be saved.
 
 ##### `:class_name`
 
@@ -926,19 +962,18 @@ class Author < ApplicationRecord
 end
 ```
 
-NOTE: You only need to specify the :counter_cache option on the `belongs_to`
+NOTE: You only need to specify the `:counter_cache` option on the `belongs_to`
 side of the association.
 
 Counter cache columns are added to the containing model's list of read-only attributes through `attr_readonly`.
 
 ##### `:dependent`
-Controls what happens to associated objects when their owner is destroyed:
+If you set the `:dependent` option to:
 
-* `:destroy` causes the associated objects to also be destroyed.
-* `:delete_all` causes the associated objects to be deleted directly from the database (callbacks are not executed).
-* `:nullify` causes the foreign keys to be set to `NULL` (callbacks are not executed).
-* `:restrict_with_exception` causes an exception to be raised if there are associated records.
-* `:restrict_with_error` causes an error to be added to the owner if there are associated objects.
+* `:destroy`, when the object is destroyed, `destroy` will be called on its
+associated objects.
+* `:delete`, when the object is destroyed, all its associated objects will be
+deleted directly from the database without calling their `destroy` method.
 
 WARNING: You should not specify this option on a `belongs_to` association that is connected with a `has_many` association on the other class. Doing so can lead to orphaned records in your database.
 
@@ -1007,7 +1042,7 @@ class Author < ApplicationRecord
 end
 ```
 
-In this case, saving or destroying an book will update the timestamp on the associated author. You can also specify a particular timestamp attribute to update:
+In this case, saving or destroying a book will update the timestamp on the associated author. You can also specify a particular timestamp attribute to update:
 
 ```ruby
 class Book < ApplicationRecord
@@ -1127,6 +1162,7 @@ When you declare a `has_one` association, the declaring class automatically gain
 * `build_association(attributes = {})`
 * `create_association(attributes = {})`
 * `create_association!(attributes = {})`
+* `reload_association`
 
 In all of these methods, `association` is replaced with the symbol passed as the first argument to `has_one`. For example, given the declaration:
 
@@ -1144,6 +1180,7 @@ account=
 build_account
 create_account
 create_account!
+reload_account
 ```
 
 NOTE: When initializing a new `has_one` or `belongs_to` association you must use the `build_` prefix to build the association, rather than the `association.build` method that would be used for `has_many` or `has_and_belongs_to_many` associations. To create one, use the `create_` prefix.
@@ -1156,10 +1193,10 @@ The `association` method returns the associated object, if any. If no associated
 @account = @supplier.account
 ```
 
-If the associated object has already been retrieved from the database for this object, the cached version will be returned. To override this behavior (and force a database read), call `#reload` on the parent object.
+If the associated object has already been retrieved from the database for this object, the cached version will be returned. To override this behavior (and force a database read), call `#reload_association` on the parent object.
 
 ```ruby
-@account = @supplier.reload.account
+@account = @supplier.reload_account
 ```
 
 ##### `association=(associate)`
@@ -1220,7 +1257,7 @@ Setting the `:as` option indicates that this is a polymorphic association. Polym
 
 ##### `:autosave`
 
-If you set the `:autosave` option to `true`, Rails will save any loaded members and destroy members that are marked for destruction whenever you save the parent object.
+If you set the `:autosave` option to `true`, Rails will save any loaded association members and destroy members that are marked for destruction whenever you save the parent object. Setting `:autosave` to `false` is not the same as not setting the `:autosave` option. If the `:autosave` option is not present, then new associated objects will be saved, but updated associated objects will not be saved.
 
 ##### `:class_name`
 
@@ -1383,7 +1420,7 @@ If either of these saves fails due to validation errors, then the assignment sta
 
 If the parent object (the one declaring the `has_one` association) is unsaved (that is, `new_record?` returns `true`) then the child objects are not saved. They will automatically when the parent object is saved.
 
-If you want to assign an object to a `has_one` association without saving the object, use the `association.build` method.
+If you want to assign an object to a `has_one` association without saving the object, use the `build_association` method.
 
 ### `has_many` Association Reference
 
@@ -1409,6 +1446,7 @@ When you declare a `has_many` association, the declaring class automatically gai
 * `collection.build(attributes = {}, ...)`
 * `collection.create(attributes = {})`
 * `collection.create!(attributes = {})`
+* `collection.reload`
 
 In all of these methods, `collection` is replaced with the symbol passed as the first argument to `has_many`, and `collection_singular` is replaced with the singularized version of that symbol. For example, given the declaration:
 
@@ -1437,11 +1475,12 @@ books.exists?(...)
 books.build(attributes = {}, ...)
 books.create(attributes = {})
 books.create!(attributes = {})
+books.reload
 ```
 
 ##### `collection`
 
-The `collection` method returns an array of all of the associated objects. If there are no associated objects, it returns an empty array.
+The `collection` method returns a Relation of all of the associated objects. If there are no associated objects, it returns an empty Relation.
 
 ```ruby
 @books = @author.books
@@ -1522,10 +1561,11 @@ The `collection.size` method returns the number of objects in the collection.
 
 ##### `collection.find(...)`
 
-The `collection.find` method finds objects within the collection. It uses the same syntax and options as `ActiveRecord::Base.find`.
+The `collection.find` method finds objects within the collection. It uses the same syntax and options as
+[`ActiveRecord::Base.find`](http://api.rubyonrails.org/classes/ActiveRecord/FinderMethods.html#method-i-find).
 
 ```ruby
-@available_books = @author.books.find(1)
+@available_book = @author.books.find(1)
 ```
 
 ##### `collection.where(...)`
@@ -1575,6 +1615,14 @@ The `collection.create` method returns a single or array of new objects of the a
 
 Does the same as `collection.create` above, but raises `ActiveRecord::RecordInvalid` if the record is invalid.
 
+##### `collection.reload`
+
+The `collection.reload` method returns a Relation of all of the associated objects, forcing a database read. If there are no associated objects, it returns an empty Relation.
+
+```ruby
+@books = @author.books.reload
+```
+
 #### Options for `has_many`
 
 While Rails uses intelligent defaults that will work well in most situations, there may be times when you want to customize the behavior of the `has_many` association reference. Such customizations can easily be accomplished by passing options when you create the association. For example, this association uses two such options:
@@ -1606,7 +1654,7 @@ Setting the `:as` option indicates that this is a polymorphic association, as di
 
 ##### `:autosave`
 
-If you set the `:autosave` option to `true`, Rails will save any loaded members and destroy members that are marked for destruction whenever you save the parent object.
+If you set the `:autosave` option to `true`, Rails will save any loaded association members and destroy members that are marked for destruction whenever you save the parent object. Setting `:autosave` to `false` is not the same as not setting the `:autosave` option. If the `:autosave` option is not present, then new associated objects will be saved, but updated associated objects will not be saved.
 
 ##### `:class_name`
 
@@ -1797,7 +1845,7 @@ The `limit` method lets you restrict the total number of objects that will be fe
 class Author < ApplicationRecord
   has_many :recent_books,
     -> { order('published_at desc').limit(100) },
-    class_name: "Book",
+    class_name: "Book"
 end
 ```
 
@@ -1841,7 +1889,7 @@ article   = Article.create(name: 'a1')
 person.articles << article
 person.articles << article
 person.articles.inspect # => [#<Article id: 5, name: "a1">, #<Article id: 5, name: "a1">]
-Reading.all.inspect  # => [#<Reading id: 12, person_id: 5, article_id: 5>, #<Reading id: 13, person_id: 5, article_id: 5>]
+Reading.all.inspect     # => [#<Reading id: 12, person_id: 5, article_id: 5>, #<Reading id: 13, person_id: 5, article_id: 5>]
 ```
 
 In the above case there are two readings and `person.articles` brings out both of
@@ -1860,7 +1908,7 @@ article   = Article.create(name: 'a1')
 person.articles << article
 person.articles << article
 person.articles.inspect # => [#<Article id: 7, name: "a1">]
-Reading.all.inspect  # => [#<Reading id: 16, person_id: 7, article_id: 7>, #<Reading id: 17, person_id: 7, article_id: 7>]
+Reading.all.inspect     # => [#<Reading id: 16, person_id: 7, article_id: 7>, #<Reading id: 17, person_id: 7, article_id: 7>]
 ```
 
 In the above case there are still two readings. However `person.articles` shows
@@ -1931,6 +1979,7 @@ When you declare a `has_and_belongs_to_many` association, the declaring class au
 * `collection.build(attributes = {})`
 * `collection.create(attributes = {})`
 * `collection.create!(attributes = {})`
+* `collection.reload`
 
 In all of these methods, `collection` is replaced with the symbol passed as the first argument to `has_and_belongs_to_many`, and `collection_singular` is replaced with the singularized version of that symbol. For example, given the declaration:
 
@@ -1959,6 +2008,7 @@ assemblies.exists?(...)
 assemblies.build(attributes = {}, ...)
 assemblies.create(attributes = {})
 assemblies.create!(attributes = {})
+assemblies.reload
 ```
 
 ##### Additional Column Methods
@@ -1970,7 +2020,7 @@ WARNING: The use of extra attributes on the join table in a `has_and_belongs_to_
 
 ##### `collection`
 
-The `collection` method returns an array of all of the associated objects. If there are no associated objects, it returns an empty array.
+The `collection` method returns a Relation of all of the associated objects. If there are no associated objects, it returns an empty Relation.
 
 ```ruby
 @assemblies = @part.assemblies
@@ -1994,11 +2044,9 @@ The `collection.delete` method removes one or more objects from the collection b
 @part.assemblies.delete(@assembly1)
 ```
 
-WARNING: This does not trigger callbacks on the join records.
-
 ##### `collection.destroy(object, ...)`
 
-The `collection.destroy` method removes one or more objects from the collection by running `destroy` on each record in the join table, including running callbacks. This does not destroy the objects.
+The `collection.destroy` method removes one or more objects from the collection by deleting records in the join table. This does not destroy the objects.
 
 ```ruby
 @part.assemblies.destroy(@assembly1)
@@ -2044,7 +2092,8 @@ The `collection.size` method returns the number of objects in the collection.
 
 ##### `collection.find(...)`
 
-The `collection.find` method finds objects within the collection. It uses the same syntax and options as `ActiveRecord::Base.find`. It also adds the additional condition that the object must be in the collection.
+The `collection.find` method finds objects within the collection. It uses the same syntax and options as
+[`ActiveRecord::Base.find`](http://api.rubyonrails.org/classes/ActiveRecord/FinderMethods.html#method-i-find).
 
 ```ruby
 @assembly = @part.assemblies.find(1)
@@ -2052,7 +2101,7 @@ The `collection.find` method finds objects within the collection. It uses the sa
 
 ##### `collection.where(...)`
 
-The `collection.where` method finds objects within the collection based on the conditions supplied but the objects are loaded lazily meaning that the database is queried only when the object(s) are accessed. It also adds the additional condition that the object must be in the collection.
+The `collection.where` method finds objects within the collection based on the conditions supplied but the objects are loaded lazily meaning that the database is queried only when the object(s) are accessed.
 
 ```ruby
 @new_assemblies = @part.assemblies.where("created_at > ?", 2.days.ago)
@@ -2084,6 +2133,14 @@ The `collection.create` method returns a new object of the associated type. This
 
 Does the same as `collection.create`, but raises `ActiveRecord::RecordInvalid` if the record is invalid.
 
+##### `collection.reload`
+
+The `collection.reload` method returns a Relation of all of the associated objects, forcing a database read. If there are no associated objects, it returns an empty Relation.
+
+```ruby
+@assemblies = @part.assemblies.reload
+```
+
 #### Options for `has_and_belongs_to_many`
 
 While Rails uses intelligent defaults that will work well in most situations, there may be times when you want to customize the behavior of the `has_and_belongs_to_many` association reference. Such customizations can easily be accomplished by passing options when you create the association. For example, this association uses two such options:
@@ -2121,7 +2178,7 @@ end
 
 ##### `:autosave`
 
-If you set the `:autosave` option to `true`, Rails will save any loaded members and destroy members that are marked for destruction whenever you save the parent object.
+If you set the `:autosave` option to `true`, Rails will save any loaded association members and destroy members that are marked for destruction whenever you save the parent object. Setting `:autosave` to `false` is not the same as not setting the `:autosave` option. If the `:autosave` option is not present, then new associated objects will be saved, but updated associated objects will not be saved.
 
 ##### `:class_name`
 
diff --git a/guides/source/autoloading_and_reloading_constants.md b/guides/source/autoloading_and_reloading_constants.md
index 61657023e7..dea87a18f8 100644
--- a/guides/source/autoloading_and_reloading_constants.md
+++ b/guides/source/autoloading_and_reloading_constants.md
@@ -330,11 +330,17 @@ its resolution next. Let's define *parent* to be that qualifying class or module
 object, that is, `Billing` in the example above. The algorithm for qualified
 constants goes like this:
 
-1. The constant is looked up in the parent and its ancestors.
+1. The constant is looked up in the parent and its ancestors. In Ruby >= 2.5,
+`Object` is skipped if present among the ancestors. `Kernel` and `BasicObject`
+are still checked though.
 
 2. If the lookup fails, `const_missing` is invoked in the parent. The default
 implementation of `const_missing` raises `NameError`, but it can be overridden.
 
+INFO. In Ruby < 2.5 `String::Hash` evaluates to `Hash` and the interpreter
+issues a warning: "toplevel constant Hash referenced by String::Hash". Starting
+with 2.5, `String::Hash` raises `NameError` because `Object` is skipped.
+
 As you see, this algorithm is simpler than the one for relative constants. In
 particular, the nesting plays no role here, and modules are not special-cased,
 if neither they nor their ancestors have the constants, `Object` is **not**
@@ -475,12 +481,21 @@ it is (edited):
 ```
 $ bin/rails r 'puts ActiveSupport::Dependencies.autoload_paths'
 .../app/assets
+.../app/channels
 .../app/controllers
+.../app/controllers/concerns
 .../app/helpers
+.../app/jobs
 .../app/mailers
 .../app/models
-.../app/controllers/concerns
 .../app/models/concerns
+.../activestorage/app/assets
+.../activestorage/app/controllers
+.../activestorage/app/javascript
+.../activestorage/app/jobs
+.../activestorage/app/models
+.../actioncable/app/assets
+.../actionview/app/assets
 .../test/mailers/previews
 ```
 
@@ -945,7 +960,7 @@ to work on some subclass, things get interesting.
 While working with `Polygon` you do not need to be aware of all its descendants,
 because anything in the table is by definition a polygon, but when working with
 subclasses Active Record needs to be able to enumerate the types it is looking
-for. Let’s see an example.
+for. Let's see an example.
 
 `Rectangle.all` only loads rectangles by adding a type constraint to the query:
 
@@ -954,7 +969,7 @@ SELECT "polygons".* FROM "polygons"
 WHERE "polygons"."type" IN ("Rectangle")
 ```
 
-Let’s introduce now a subclass of `Rectangle`:
+Let's introduce now a subclass of `Rectangle`:
 
 ```ruby
 # app/models/square.rb
@@ -969,7 +984,7 @@ SELECT "polygons".* FROM "polygons"
 WHERE "polygons"."type" IN ("Rectangle", "Square")
 ```
 
-But there’s a caveat here: How does Active Record know that the class `Square`
+But there's a caveat here: How does Active Record know that the class `Square`
 exists at all?
 
 Even if the file `app/models/square.rb` exists and defines the `Square` class,
@@ -983,20 +998,19 @@ WHERE "polygons"."type" IN ("Rectangle")
 That is not a bug, the query includes all *known* descendants of `Rectangle`.
 
 A way to ensure this works correctly regardless of the order of execution is to
-load the leaves of the tree by hand at the bottom of the file that defines the
-root class:
+manually load the direct subclasses at the bottom of the file that defines each
+intermediate class:
 
 ```ruby
-# app/models/polygon.rb
-class Polygon < ApplicationRecord
+# app/models/rectangle.rb
+class Rectangle < Polygon
 end
-require_dependency ‘square’
+require_dependency 'square'
 ```
 
-Only the leaves that are **at least grandchildren** need to be loaded this
-way. Direct subclasses do not need to be preloaded. If the hierarchy is
-deeper, intermediate classes will be autoloaded recursively from the bottom
-because their constant will appear in the class definitions as superclass.
+This needs to happen for every intermediate (non-root and non-leaf) class. The
+root class does not scope the query by type, and therefore does not necessarily
+have to know all its descendants.
 
 ### Autoloading and `require`
 
@@ -1041,7 +1055,7 @@ end
 
 The purpose of this setup would be that the application uses the class that
 corresponds to the environment via `AUTH_SERVICE`. In development mode
-`MockedAuthService` gets autoloaded when the initializer runs. Let’s suppose
+`MockedAuthService` gets autoloaded when the initializer runs. Let's suppose
 we do some requests, change its implementation, and hit the application again.
 To our surprise the changes are not reflected. Why?
 
@@ -1170,6 +1184,8 @@ end
 
 #### Qualified References
 
+WARNING. This gotcha is only possible in Ruby < 2.5.
+
 Given
 
 ```ruby
diff --git a/guides/source/caching_with_rails.md b/guides/source/caching_with_rails.md
index 6c734c1d78..780e69c146 100644
--- a/guides/source/caching_with_rails.md
+++ b/guides/source/caching_with_rails.md
@@ -32,7 +32,7 @@ Basic Caching
 This is an introduction to three types of caching techniques: page, action and
 fragment caching. By default Rails provides fragment caching. In order to use
 page and action caching you will need to add `actionpack-page_caching` and
-`actionpack-action_caching` to your Gemfile.
+`actionpack-action_caching` to your `Gemfile`.
 
 By default, caching is only enabled in your production environment. To play
 around with caching locally you'll want to enable caching in your local
@@ -175,10 +175,28 @@ class Game < ApplicationRecord
 end
 ```
 
-With `touch` set to true, any action which changes `updated_at` for a game
+With `touch` set to `true`, any action which changes `updated_at` for a game
 record will also change it for the associated product, thereby expiring the
 cache.
 
+### Shared Partial Caching
+
+It is possible to share partials and associated caching between files with different mime types. For example shared partial caching allows template writers to share a partial between HTML and JavaScript files. When templates are collected in the template resolver file paths they only include the template language extension and not the mime type. Because of this templates can be used for multiple mime types. Both HTML and JavaScript requests will respond to the following code:
+
+```ruby
+render(partial: 'hotels/hotel', collection: @hotels, cached: true)
+```
+
+Will load a file named `hotels/hotel.erb`.
+
+Another option is to include the full filename of the partial to render.
+
+```ruby
+render(partial: 'hotels/hotel.html.erb', collection: @hotels, cached: true)
+```
+
+Will load a file named `hotels/hotel.html.erb` in any file mime type, for example you could include this partial in a JavaScript file.
+
 ### Managing dependencies
 
 In order to correctly invalidate the cache, you need to properly define the
@@ -198,11 +216,11 @@ render "comments/comments"
 render 'comments/comments'
 render('comments/comments')
 
-render "header" => render("comments/header")
+render "header" translates to render("comments/header")
 
-render(@topic)         => render("topics/topic")
-render(topics)         => render("topics/topic")
-render(message.topics) => render("topics/topic")
+render(@topic)         translates to render("topics/topic")
+render(topics)         translates to render("topics/topic")
+render(message.topics) translates to render("topics/topic")
 ```
 
 On the other hand, some calls need to be changed to make caching work properly.
@@ -270,9 +288,9 @@ simply be explicit in a comment, like:
 
 Sometimes you need to cache a particular value or query result instead of caching view fragments. Rails' caching mechanism works great for storing __any__ kind of information.
 
-The most efficient way to implement low-level caching is using the `Rails.cache.fetch` method. This method does both reading and writing to the cache. When passed only a single argument, the key is fetched and value from the cache is returned. If a block is passed, the result of the block will be cached to the given key and the result is returned.
+The most efficient way to implement low-level caching is using the `Rails.cache.fetch` method. This method does both reading and writing to the cache. When passed only a single argument, the key is fetched and value from the cache is returned. If a block is passed, that block will be executed in the event of a cache miss. The return value of the block will be written to the cache under the given cache key, and that return value will be returned. In case of cache hit, the cached value will be returned without executing the block.
 
-Consider the following example. An application has a `Product` model with an instance method that looks up the product’s price on a competing website. The data returned by this method would be perfect for low-level caching:
+Consider the following example. An application has a `Product` model with an instance method that looks up the product's price on a competing website. The data returned by this method would be perfect for low-level caching:
 
 ```ruby
 class Product < ApplicationRecord
@@ -284,7 +302,7 @@ class Product < ApplicationRecord
 end
 ```
 
-NOTE: Notice that in this example we used the `cache_key` method, so the resulting cache-key will be something like `products/233-20140225082222765838000/competing_price`. `cache_key` generates a string based on the model’s `id` and `updated_at` attributes. This is a common convention and has the benefit of invalidating the cache whenever the product is updated. In general, when you use low-level caching for instance level information, you need to generate a cache key.
+NOTE: Notice that in this example we used the `cache_key` method, so the resulting cache key will be something like `products/233-20140225082222765838000/competing_price`. `cache_key` generates a string based on the model's `id` and `updated_at` attributes. This is a common convention and has the benefit of invalidating the cache whenever the product is updated. In general, when you use low-level caching for instance level information, you need to generate a cache key.
 
 ### SQL Caching
 
@@ -348,9 +366,9 @@ There are some common options used by all cache implementations. These can be pa
 
 * `:namespace` - This option can be used to create a namespace within the cache store. It is especially useful if your application shares a cache with other applications.
 
-* `:compress` - This option can be used to indicate that compression should be used in the cache. This can be useful for transferring large cache entries over a slow network.
+* `:compress` - Enabled by default. Compresses cache entries so more data can be stored in the same memory footprint, leading to fewer cache evictions and higher hit rates.
 
-* `:compress_threshold` - This option is used in conjunction with the `:compress` option to indicate a threshold under which cache entries should not be compressed. This defaults to 16 kilobytes.
+* `:compress_threshold` - Defaults to 1kB. Cache entries larger than this threshold, specified in bytes, are compressed.
 
 * `:expires_in` - This option sets an expiration time in seconds for the cache entry when it will be automatically removed from the cache.
 
@@ -381,12 +399,17 @@ config.cache_store = :memory_store, { size: 64.megabytes }
 ```
 
 If you're running multiple Ruby on Rails server processes (which is the case
-if you're using mongrel_cluster or Phusion Passenger), then your Rails server
+if you're using Phusion Passenger or puma clustered mode), then your Rails server
 process instances won't be able to share cache data with each other. This cache
 store is not appropriate for large application deployments. However, it can
 work well for small, low traffic sites with only a couple of server processes,
 as well as development and test environments.
 
+New Rails projects are configured to use this implementation in development environment by default.
+
+NOTE: Since processes will not share cache data when using `:memory_store`,
+it will not be possible to manually read, write or expire the cache via the Rails console.
+
 ### ActiveSupport::Cache::FileStore
 
 This cache store uses the file system to store entries. The path to the directory where the store files will be stored must be specified when initializing the cache.
@@ -396,14 +419,15 @@ config.cache_store = :file_store, "/path/to/cache/directory"
 ```
 
 With this cache store, multiple server processes on the same host can share a
-cache. The cache store is appropriate for low to medium traffic sites that are
+cache. This cache store is appropriate for low to medium traffic sites that are
 served off one or two hosts. Server processes running on different hosts could
 share a cache by using a shared file system, but that setup is not recommended.
 
 As the cache will grow until the disk is full, it is recommended to
 periodically clear out old entries.
 
-This is the default cache store implementation.
+This is the default cache store implementation (at `"#{root}/tmp/cache/"`) if
+no explicit `config.cache_store` is supplied.
 
 ### ActiveSupport::Cache::MemCacheStore
 
@@ -420,6 +444,53 @@ The `write` and `fetch` methods on this cache accept two additional options that
 config.cache_store = :mem_cache_store, "cache-1.example.com", "cache-2.example.com"
 ```
 
+### ActiveSupport::Cache::RedisCacheStore
+
+The Redis cache store takes advantage of Redis support for least-recently-used
+and least-frequently-used key eviction when it reaches max memory, allowing it
+to behave much like a Memcached cache server.
+
+Deployment note: Redis doesn't expire keys by default, so take care to use a
+dedicated Redis cache server. Don't fill up your persistent-Redis server with
+volatile cache data! Read the
+[Redis cache server setup guide](https://redis.io/topics/lru-cache) in detail.
+
+For an all-cache Redis server, set `maxmemory-policy` to an `allkeys` policy.
+Redis 4+ support least-frequently-used (`allkeys-lfu`) eviction, an excellent
+default choice. Redis 3 and earlier should use `allkeys-lru` for
+least-recently-used eviction.
+
+Set cache read and write timeouts relatively low. Regenerating a cached value
+is often faster than waiting more than a second to retrieve it. Both read and
+write timeouts default to 1 second, but may be set lower if your network is
+consistently low latency.
+
+Cache reads and writes never raise exceptions. They just return `nil` instead,
+behaving as if there was nothing in the cache. To gauge whether your cache is
+hitting exceptions, you may provide an `error_handler` to report to an
+exception gathering service. It must accept three keyword arguments: `method`,
+the cache store method that was originally called; `returning`, the value that
+was returned to the user, typically `nil`; and `exception`, the exception that
+was rescued.
+
+Putting it all together, a production Redis cache store may look something
+like this:
+
+```ruby
+cache_servers = %w[ "redis://cache-01:6379/0", "redis://cache-02:6379/0", … ],
+config.cache_store = :redis_cache_store, url: cache_servers,
+
+  connect_timeout: 30,  # Defaults to 20 seconds
+  read_timeout:    0.2, # Defaults to 1 second
+  write_timeout:   0.2, # Defaults to 1 second
+
+  error_handler: -> (method:, returning:, exception:) {
+    # Report errors to Sentry as warnings
+    Raven.capture_exception exception, level: 'warning",
+      tags: { method: method, returning: returning }
+  }
+```
+
 ### ActiveSupport::Cache::NullStore
 
 This cache store implementation is meant to be used only in development or test environments and it never stores anything. This can be very useful in development when you have code that interacts directly with `Rails.cache` but caching may interfere with being able to see the results of code changes. With this cache store, all `fetch` and `read` operations will result in a miss.
@@ -512,6 +583,30 @@ class ProductsController < ApplicationController
 end
 ```
 
+Sometimes we want to cache response, for example a static page, that never gets
+expired. To achieve this, we can use `http_cache_forever` helper and by doing
+so browser and proxies will cache it indefinitely.
+
+By default cached responses will be private, cached only on the user's web
+browser. To allow proxies to cache the response, set `public: true` to indicate
+that they can serve the cached response to all users.
+
+Using this helper, `last_modified` header is set to `Time.new(2011, 1, 1).utc`
+and `expires` header is set to a 100 years.
+
+WARNING: Use this method carefully as browser/proxy won't be able to invalidate
+the cached response unless browser cache is forcefully cleared.
+
+```ruby
+class HomeController < ApplicationController
+  def index
+    http_cache_forever(public: true) do
+      render
+    end
+  end
+end
+```
+
 ### Strong v/s Weak ETags
 
 Rails generates weak ETags by default. Weak ETags allow semantically equivalent
@@ -546,6 +641,20 @@ You can also set the strong ETag directly on the response.
   response.strong_etag = response.body # => "618bbc92e2d35ea1945008b42799b0e7"
 ```
 
+Caching in Development
+----------------------
+
+It's common to want to test the caching strategy of your application
+in development mode. Rails provides the rake task `dev:cache` to
+easily toggle caching on/off.
+
+```bash
+$ bin/rails dev:cache
+Development mode is now being cached.
+$ bin/rails dev:cache
+Development mode is no longer being cached.
+```
+
 References
 ----------
 
diff --git a/guides/source/command_line.md b/guides/source/command_line.md
index f766403228..648645af7c 100644
--- a/guides/source/command_line.md
+++ b/guides/source/command_line.md
@@ -63,7 +63,7 @@ With no further work, `rails server` will run our new shiny Rails app:
 $ cd commandsapp
 $ bin/rails server
 => Booting Puma
-=> Rails 5.0.0 application starting in development on http://0.0.0.0:3000
+=> Rails 5.1.0 application starting in development on http://0.0.0.0:3000
 => Run `rails server -h` for more startup options
 Puma starting in single mode...
 * Version 3.0.2 (ruby 2.3.0-p0), codename: Plethora of Penguin Pinatas
@@ -102,6 +102,7 @@ Please choose a generator below.
 
 Rails:
   assets
+  channel
   controller
   generator
   ...
@@ -209,7 +210,7 @@ Description:
     Create rails files for model generator.
 ```
 
-NOTE: For a list of available field types, refer to the [API documentation](http://api.rubyonrails.org/classes/ActiveRecord/ConnectionAdapters/TableDefinition.html#method-i-column) for the column method for the `TableDefinition` class.
+NOTE: For a list of available field types for the `type` parameter, refer to the [API documentation](http://api.rubyonrails.org/classes/ActiveRecord/ConnectionAdapters/SchemaStatements.html#method-i-add_column) for the add_column method for the `SchemaStatements` module. The `index` parameter generates a corresponding index for the column.
 
 But instead of generating a model directly (which we'll be doing later), let's set up a scaffold. A **scaffold** in Rails is a full set of model, database migration for that model, controller to manipulate it, views to view and manipulate the data, and a test suite for each of the above.
 
@@ -241,6 +242,8 @@ $ bin/rails generate scaffold HighScore game:string score:integer
     invoke    jbuilder
     create      app/views/high_scores/index.json.jbuilder
     create      app/views/high_scores/show.json.jbuilder
+    invoke  test_unit
+    create    test/system/high_scores_test.rb
     invoke  assets
     invoke    coffee
     create      app/assets/javascripts/high_scores.coffee
@@ -262,12 +265,12 @@ $ bin/rails db:migrate
 ==  CreateHighScores: migrated (0.0019s) ======================================
 ```
 
-INFO: Let's talk about unit tests. Unit tests are code that tests and makes assertions 
-about code. In unit testing, we take a little part of code, say a method of a model, 
-and test its inputs and outputs. Unit tests are your friend. The sooner you make 
-peace with the fact that your quality of life will drastically increase when you unit 
-test your code, the better. Seriously. Please visit 
-[the testing guide](http://guides.rubyonrails.org/testing.html) for an in-depth 
+INFO: Let's talk about unit tests. Unit tests are code that tests and makes assertions
+about code. In unit testing, we take a little part of code, say a method of a model,
+and test its inputs and outputs. Unit tests are your friend. The sooner you make
+peace with the fact that your quality of life will drastically increase when you unit
+test your code, the better. Seriously. Please visit
+[the testing guide](http://guides.rubyonrails.org/testing.html) for an in-depth
 look at unit testing.
 
 Let's see the interface Rails created for us.
@@ -287,14 +290,14 @@ INFO: You can also use the alias "c" to invoke the console: `rails c`.
 You can specify the environment in which the `console` command should operate.
 
 ```bash
-$ bin/rails console staging
+$ bin/rails console -e staging
 ```
 
 If you wish to test out some code without changing any data, you can do that by invoking `rails console --sandbox`.
 
 ```bash
 $ bin/rails console --sandbox
-Loading development environment in sandbox (Rails 5.0.0)
+Loading development environment in sandbox (Rails 5.1.0)
 Any modifications you make will be rolled back on exit
 irb(main):001:0>
 ```
@@ -407,8 +410,8 @@ db:fixtures:load                    Loads fixtures into the ...
 db:migrate                          Migrate the database ...
 db:migrate:status                   Display status of migrations
 db:rollback                         Rolls the schema back to ...
-db:schema:cache:clear               Clears a db/schema_cache.dump file
-db:schema:cache:dump                Creates a db/schema_cache.dump file
+db:schema:cache:clear               Clears a db/schema_cache.yml file
+db:schema:cache:dump                Creates a db/schema_cache.yml file
 db:schema:dump                      Creates a db/schema.rb file ...
 db:schema:load                      Loads a schema.rb file ...
 db:seed                             Loads the seed data ...
@@ -428,12 +431,12 @@ INFO: You can also use `bin/rails -T`  to get the list of tasks.
 ```bash
 $ bin/rails about
 About your application's environment
-Rails version             5.0.0
+Rails version             5.1.0
 Ruby version              2.2.2 (x86_64-linux)
 RubyGems version          2.4.6
-Rack version              1.6
+Rack version              2.0.1
 JavaScript Runtime        Node.js (V8)
-Middleware                Rack::Sendfile, ActionDispatch::Static, ActionDispatch::Executor, #<ActiveSupport::Cache::Strategy::LocalCache::Middleware:0x007ffd131a7c88>, Rack::Runtime, Rack::MethodOverride, ActionDispatch::RequestId, Rails::Rack::Logger, ActionDispatch::ShowExceptions, ActionDispatch::DebugExceptions, ActionDispatch::RemoteIp, ActionDispatch::Reloader, ActionDispatch::Callbacks, ActiveRecord::Migration::CheckPending, ActionDispatch::Cookies, ActionDispatch::Session::CookieStore, ActionDispatch::Flash, Rack::Head, Rack::ConditionalGet, Rack::ETag
+Middleware:               Rack::Sendfile, ActionDispatch::Static, ActionDispatch::Executor, ActiveSupport::Cache::Strategy::LocalCache::Middleware, Rack::Runtime, Rack::MethodOverride, ActionDispatch::RequestId, ActionDispatch::RemoteIp, Sprockets::Rails::QuietAssets, Rails::Rack::Logger, ActionDispatch::ShowExceptions, WebConsole::Middleware, ActionDispatch::DebugExceptions, ActionDispatch::Reloader, ActionDispatch::Callbacks, ActiveRecord::Migration::CheckPending, ActionDispatch::Cookies, ActionDispatch::Session::CookieStore, ActionDispatch::Flash, Rack::Head, Rack::ConditionalGet, Rack::ETag
 Application root          /home/foobar/commandsapp
 Environment               development
 Database adapter          sqlite3
@@ -497,7 +500,13 @@ app/models/article.rb:
 
 NOTE. When using specific annotations and custom annotations, the annotation name (FIXME, BUG etc) is not displayed in the output lines.
 
-By default, `rails notes` will look in the `app`, `config`, `db`, `lib` and `test` directories. If you would like to search other directories, you can provide them as a comma separated list in an environment variable `SOURCE_ANNOTATION_DIRECTORIES`.
+By default, `rails notes` will look in the `app`, `config`, `db`, `lib` and `test` directories. If you would like to search other directories, you can configure them using `config.annotations.register_directories` option.
+
+```ruby
+config.annotations.register_directories("spec", "vendor")
+```
+
+You can also provide them as a comma separated list in the environment variable `SOURCE_ANNOTATION_DIRECTORIES`.
 
 ```bash
 $ export SOURCE_ANNOTATION_DIRECTORIES='spec,vendor'
@@ -527,7 +536,8 @@ The `tmp:` namespaced tasks will help you clear and create the `Rails.root/tmp`
 
 * `rails tmp:cache:clear` clears `tmp/cache`.
 * `rails tmp:sockets:clear` clears `tmp/sockets`.
-* `rails tmp:clear` clears all cache and sockets files.
+* `rails tmp:screenshots:clear` clears `tmp/screenshots`.
+* `rails tmp:clear` clears all cache, sockets and screenshot files.
 * `rails tmp:create` creates tmp directories for cache, sockets and pids.
 
 ### Miscellaneous
@@ -635,17 +645,20 @@ $ cat config/database.yml
 # Configure Using Gemfile
 # gem 'pg'
 #
-development:
+default: &default
   adapter: postgresql
   encoding: unicode
+  # For details on connection pooling, see Rails configuration guide
+  # http://guides.rubyonrails.org/configuring.html#database-pooling
+  pool: <%= ENV.fetch("RAILS_MAX_THREADS") { 5 } %>
+
+development:
+  <<: *default
   database: gitapp_development
-  pool: 5
-  username: gitapp
-  password:
 ...
 ...
 ```
 
-It also generated some lines in our database.yml configuration corresponding to our choice of PostgreSQL for database.
+It also generated some lines in our `database.yml` configuration corresponding to our choice of PostgreSQL for database.
 
 NOTE. The only catch with using the SCM options is that you have to make your application's directory first, then initialize your SCM, then you can run the `rails new` command to generate the basis of your app.
diff --git a/guides/source/configuring.md b/guides/source/configuring.md
index b3d3b2c681..b1e472bb74 100644
--- a/guides/source/configuring.md
+++ b/guides/source/configuring.md
@@ -32,7 +32,7 @@ Configuring Rails Components
 
 In general, the work of configuring Rails means configuring the components of Rails, as well as configuring Rails itself. The configuration file `config/application.rb` and environment-specific configuration files (such as `config/environments/production.rb`) allow you to specify the various settings that you want to pass down to all of the components.
 
-For example, the `config/application.rb` file includes this setting:
+For example, you could add this setting to `config/application.rb` file:
 
 ```ruby
 config.time_zone = 'Central Time (US & Canada)'
@@ -71,7 +71,7 @@ These configuration methods are to be called on a `Rails::Railtie` object, such
 * `config.beginning_of_week` sets the default beginning of week for the
 application. Accepts a valid week day symbol (e.g. `:monday`).
 
-* `config.cache_store` configures which cache store to use for Rails caching. Options include one of the symbols `:memory_store`, `:file_store`, `:mem_cache_store`, `:null_store`, or an object that implements the cache API. Defaults to `:file_store` if the directory `tmp/cache` exists, and to `:memory_store` otherwise.
+* `config.cache_store` configures which cache store to use for Rails caching. Options include one of the symbols `:memory_store`, `:file_store`, `:mem_cache_store`, `:null_store`, or an object that implements the cache API. Defaults to `:file_store`.
 
 * `config.colorize_logging` specifies whether or not to use ANSI color codes when logging information. Defaults to `true`.
 
@@ -94,6 +94,8 @@ application. Accepts a valid week day symbol (e.g. `:monday`).
 
 * `config.eager_load_paths` accepts an array of paths from which Rails will eager load on boot if cache classes is enabled. Defaults to every folder in the `app` directory of the application.
 
+* `config.enable_dependency_loading`: when true, enables autoloading, even if the application is eager loaded and `config.cache_classes` is set as true. Defaults to false.
+
 * `config.encoding` sets up the application-wide encoding. Defaults to UTF-8.
 
 * `config.exceptions_app` sets the exceptions application invoked by the ShowException middleware when an exception happens. Defaults to `ActionDispatch::PublicExceptions.new(Rails.public_path)`.
@@ -106,9 +108,9 @@ application. Accepts a valid week day symbol (e.g. `:monday`).
 you don't want shown in the logs, such as passwords or credit card
 numbers. By default, Rails filters out passwords by adding `Rails.application.config.filter_parameters += [:password]` in `config/initializers/filter_parameter_logging.rb`. Parameters filter works by partial matching regular expression.
 
-* `config.force_ssl` forces all requests to be served over HTTPS by using the `ActionDispatch::SSL` middleware, and sets `config.action_mailer.default_url_options` to be `{ protocol: 'https' }`. This can be configured by setting `config.ssl_options` - see the [ActionDispatch::SSL documentation](http://edgeapi.rubyonrails.org/classes/ActionDispatch/SSL.html) for details.
+* `config.force_ssl` forces all requests to be served over HTTPS by using the `ActionDispatch::SSL` middleware, and sets `config.action_mailer.default_url_options` to be `{ protocol: 'https' }`. This can be configured by setting `config.ssl_options` - see the [ActionDispatch::SSL documentation](http://api.rubyonrails.org/classes/ActionDispatch/SSL.html) for details.
 
-* `config.log_formatter` defines the formatter of the Rails logger. This option defaults to an instance of `ActiveSupport::Logger::SimpleFormatter` for all modes except production, where it defaults to `Logger::Formatter`. If you are setting a value for `config.logger` you must manually pass the value of your formatter to your logger before it is wrapped in an `ActiveSupport::TaggedLogging` instance, Rails will not do it for you.
+* `config.log_formatter` defines the formatter of the Rails logger. This option defaults to an instance of `ActiveSupport::Logger::SimpleFormatter` for all modes. If you are setting a value for `config.logger` you must manually pass the value of your formatter to your logger before it is wrapped in an `ActiveSupport::TaggedLogging` instance, Rails will not do it for you.
 
 * `config.log_level` defines the verbosity of the Rails logger. This option
 defaults to `:debug` for all environments. The available log levels are: `:debug`,
@@ -129,18 +131,18 @@ defaults to `:debug` for all environments. The available log levels are: `:debug
 
     mylogger           = MyLogger.new(STDOUT)
     mylogger.formatter = config.log_formatter
-    config.logger = ActiveSupport::TaggedLogging.new(mylogger)
+    config.logger      = ActiveSupport::TaggedLogging.new(mylogger)
     ```
 
 * `config.middleware` allows you to configure the application's middleware. This is covered in depth in the [Configuring Middleware](#configuring-middleware) section below.
 
 * `config.reload_classes_only_on_change` enables or disables reloading of classes only when tracked files change. By default tracks everything on autoload paths and is set to `true`. If `config.cache_classes` is `true`, this option is ignored.
 
-* `secrets.secret_key_base` is used for specifying a key which allows sessions for the application to be verified against a known secure key to prevent tampering. Applications get `secrets.secret_key_base` initialized to a random key present in `config/secrets.yml`.
+* `secret_key_base` is used for specifying a key which allows sessions for the application to be verified against a known secure key to prevent tampering. Applications get a random generated key in test and development environments, other environments should set one in `config/credentials.yml.enc`.
 
 * `config.public_file_server.enabled` configures Rails to serve static files from the public directory. This option defaults to `true`, but in the production environment it is set to `false` because the server software (e.g. NGINX or Apache) used to run the application should serve static files instead. If you are running or testing your app in production mode using WEBrick (it is not recommended to use WEBrick in production) set the option to `true.` Otherwise, you won't be able to use page caching and request for files that exist under the public directory.
 
-* `config.session_store` is usually set up in `config/initializers/session_store.rb` and specifies what class to use to store the session. Possible values are `:cookie_store` which is the default, `:mem_cache_store`, and `:disabled`. The last one tells Rails not to deal with sessions. Custom session stores can also be specified:
+* `config.session_store` specifies what class to use to store the session. Possible values are `:cookie_store` which is the default, `:mem_cache_store`, and `:disabled`. The last one tells Rails not to deal with sessions. Defaults to a cookie store with application name as the session key. Custom session stores can also be specified:
 
     ```ruby
     config.session_store :my_custom_store
@@ -155,30 +157,34 @@ defaults to `:debug` for all environments. The available log levels are: `:debug
 * `config.assets.enabled` a flag that controls whether the asset
 pipeline is enabled. It is set to `true` by default.
 
-* `config.assets.raise_runtime_errors` Set this flag to `true` to enable additional runtime error checking. Recommended in `config/environments/development.rb` to minimize unexpected behavior when deploying to `production`.
-
 * `config.assets.css_compressor` defines the CSS compressor to use. It is set by default by `sass-rails`. The unique alternative value at the moment is `:yui`, which uses the `yui-compressor` gem.
 
 * `config.assets.js_compressor` defines the JavaScript compressor to use. Possible values are `:closure`, `:uglifier` and `:yui` which require the use of the `closure-compiler`, `uglifier` or `yui-compressor` gems respectively.
 
-* `config.assets.gzip` a flag that enables the creation of gzipped version of compiled assets, along with non-gzipped assets. Set to `true` by default.  
+* `config.assets.gzip` a flag that enables the creation of gzipped version of compiled assets, along with non-gzipped assets. Set to `true` by default.
 
 * `config.assets.paths` contains the paths which are used to look for assets. Appending paths to this configuration option will cause those paths to be used in the search for assets.
 
 * `config.assets.precompile` allows you to specify additional assets (other than `application.css` and `application.js`) which are to be precompiled when `rake assets:precompile` is run.
 
+* `config.assets.unknown_asset_fallback` allows you to modify the behavior of the asset pipeline when an asset is not in the pipeline, if you use sprockets-rails 3.2.0 or newer. Defaults to `true`.
+
 * `config.assets.prefix` defines the prefix where assets are served from. Defaults to `/assets`.
 
 * `config.assets.manifest` defines the full path to be used for the asset precompiler's manifest file. Defaults to a file named `manifest-<random>.json` in the `config.assets.prefix` directory within the public folder.
 
-* `config.assets.digest` enables the use of MD5 fingerprints in asset names. Set to `true` by default.
+* `config.assets.digest` enables the use of SHA256 fingerprints in asset names. Set to `true` by default.
 
 * `config.assets.debug` disables the concatenation and compression of assets. Set to `true` by default in `development.rb`.
 
+* `config.assets.version` is an option string that is used in SHA256 hash generation. This can be changed to force all files to be recompiled.
+
 * `config.assets.compile` is a boolean that can be used to turn on live Sprockets compilation in production.
 
 * `config.assets.logger` accepts a logger conforming to the interface of Log4r or the default Ruby `Logger` class. Defaults to the same configured at `config.logger`. Setting `config.assets.logger` to `false` will turn off served assets logging.
 
+* `config.assets.quiet` disables logging of assets requests. Set to `true` by default in `development.rb`.
+
 ### Configuring Generators
 
 Rails allows you to alter what generators are used with the `config.generators` method. This method takes a block:
@@ -296,6 +302,8 @@ All these configuration options are delegated to the `I18n` library.
 
     ```ruby
     config.i18n.fallbacks = { az: :tr, da: [:de, :en] }
+    #or
+    config.i18n.fallbacks.map = { az: :tr, da: [:de, :en] }
     ```
 
 ### Configuring Active Record
@@ -314,13 +322,17 @@ All these configuration options are delegated to the `I18n` library.
 
 * `config.active_record.schema_migrations_table_name` lets you set a string to be used as the name of the schema migrations table.
 
+* `config.active_record.internal_metadata_table_name` lets you set a string to be used as the name of the internal metadata table.
+
+* `config.active_record.protected_environments` lets you set an array of names of environments where destructive actions should be prohibited.
+
 * `config.active_record.pluralize_table_names` specifies whether Rails will look for singular or plural table names in the database. If set to `true` (the default), then the Customer class will use the `customers` table. If set to false, then the Customer class will use the `customer` table.
 
 * `config.active_record.default_timezone` determines whether to use `Time.local` (if set to `:local`) or `Time.utc` (if set to `:utc`) when pulling dates and times from the database. The default is `:utc`.
 
 * `config.active_record.schema_format` controls the format for dumping the database schema to a file. The options are `:ruby` (the default) for a database-independent version that depends on migrations, or `:sql` for a set of (potentially database-dependent) SQL statements.
 
-* `config.active_record.error_on_ignored_order_or_limit` specifies if an error should be raised if the order or limit of a query is ignored during a batch query. The options are `true` (raise error) or `false` (warn). Default is `false`.
+* `config.active_record.error_on_ignored_order` specifies if an error should be raised if the order of a query is ignored during a batch query. The options are `true` (raise error) or `false` (warn). Default is `false`.
 
 * `config.active_record.timestamped_migrations` controls whether migrations are numbered with serial integers or with timestamps. The default is `true`, to use timestamps, which are preferred if there are multiple developers working on the same application.
 
@@ -340,9 +352,9 @@ All these configuration options are delegated to the `I18n` library.
   `config/environments/production.rb` which is generated by Rails. The
   default value is `true` if this configuration is not set.
 
-* `config.active_record.dump_schemas` controls which database schemas will be dumped when calling db:structure:dump.
-  The options are `:schema_search_path` (the default) which dumps any schemas listed in schema_search_path,
-  `:all` which always dumps all schemas regardless of the schema_search_path,
+* `config.active_record.dump_schemas` controls which database schemas will be dumped when calling `db:structure:dump`.
+  The options are `:schema_search_path` (the default) which dumps any schemas listed in `schema_search_path`,
+  `:all` which always dumps all schemas regardless of the `schema_search_path`,
   or a string of comma separated schemas.
 
 * `config.active_record.belongs_to_required_by_default` is a boolean value and
@@ -352,19 +364,46 @@ All these configuration options are delegated to the `I18n` library.
 * `config.active_record.warn_on_records_fetched_greater_than` allows setting a
   warning threshold for query result size. If the number of records returned
   by a query exceeds the threshold, a warning is logged. This can be used to
-  identify queries which might be causing memory bloat.
+  identify queries which might be causing a memory bloat.
 
 * `config.active_record.index_nested_attribute_errors` allows errors for nested
-  has_many relationships to be displayed with an index as well as the error.
+  `has_many` relationships to be displayed with an index as well as the error.
   Defaults to `false`.
 
+* `config.active_record.use_schema_cache_dump` enables users to get schema cache information
+  from `db/schema_cache.yml` (generated by `bin/rails db:schema:cache:dump`), instead of
+  having to send a query to the database to get this information.
+  Defaults to `true`.
+
 The MySQL adapter adds one additional configuration option:
 
 * `ActiveRecord::ConnectionAdapters::Mysql2Adapter.emulate_booleans` controls whether Active Record will consider all `tinyint(1)` columns as booleans. Defaults to `true`.
 
+The SQLite3Adapter adapter adds one additional configuration option:
+
+* `ActiveRecord::ConnectionAdapters::SQLite3Adapter.represent_boolean_as_integer`
+indicates whether boolean values are stored in sqlite3 databases as 1 and 0 or
+'t' and 'f'. Leaving `ActiveRecord::ConnectionAdapters::SQLite3Adapter.represent_boolean_as_integer`
+set to false is deprecated. SQLite databases have used 't' and 'f' to serialize
+boolean values and must have old data converted to 1 and 0 (its native boolean
+serialization) before setting this flag to true. Conversion can be accomplished
+by setting up a Rake task which runs
+
+    ```ruby
+    ExampleModel.where("boolean_column = 't'").update_all(boolean_column: 1)
+    ExampleModel.where("boolean_column = 'f'").update_all(boolean_column: 0)
+    ```
+
+  for all models and all boolean columns, after which the flag must be set to true
+by adding the following to your `application.rb` file:
+
+    ```ruby
+    Rails.application.config.active_record.sqlite3.represent_boolean_as_integer = true
+    ```
+
 The schema dumper adds one additional configuration option:
 
-* `ActiveRecord::SchemaDumper.ignore_tables` accepts an array of tables that should _not_ be included in any generated schema file. This setting is ignored unless `config.active_record.schema_format == :ruby`.
+* `ActiveRecord::SchemaDumper.ignore_tables` accepts an array of tables that should _not_ be included in any generated schema file.
 
 ### Configuring Action Controller
 
@@ -388,6 +427,8 @@ The schema dumper adds one additional configuration option:
 
 * `config.action_controller.per_form_csrf_tokens` configures whether CSRF tokens are only valid for the method/action they were generated for.
 
+* `config.action_controller.default_protect_from_forgery` determines whether forgery protection is added on `ActionController:Base`. This is false by default, but enabled when loading defaults for Rails 5.2.
+
 * `config.action_controller.relative_url_root` can be used to tell Rails that you are [deploying to a subdirectory](configuring.html#deploy-to-a-subdirectory-relative-url-root). The default is `ENV['RAILS_RELATIVE_URL_ROOT']`.
 
 * `config.action_controller.permit_all_parameters` sets all the parameters for mass assignment to be permitted by default. The default value is `false`.
@@ -396,6 +437,22 @@ The schema dumper adds one additional configuration option:
 
 * `config.action_controller.always_permitted_parameters` sets a list of whitelisted parameters that are permitted by default. The default values are `['controller', 'action']`.
 
+* `config.action_controller.enable_fragment_cache_logging` determines whether to log fragment cache reads and writes in verbose format as follows:
+
+    ```
+    Read fragment views/v1/2914079/v1/2914079/recordings/70182313-20160225015037000000/d0bdf2974e1ef6d31685c3b392ad0b74 (0.6ms)
+    Rendered messages/_message.html.erb in 1.2 ms [cache hit]
+    Write fragment views/v1/2914079/v1/2914079/recordings/70182313-20160225015037000000/3b4e249ac9d168c617e32e84b99218b5 (1.1ms)
+    Rendered recordings/threads/_thread.html.erb in 1.5 ms [cache miss]
+    ```
+
+  By default it is set to `false` which results in following output:
+
+    ```
+    Rendered messages/_message.html.erb in 1.2 ms [cache hit]
+    Rendered recordings/threads/_thread.html.erb in 1.5 ms [cache miss]
+    ```
+
 ### Configuring Action Dispatch
 
 * `config.action_dispatch.session_store` sets the name of the store for session data. The default is `:cookie_store`; other valid options include `:active_record_store`, `:mem_cache_store` or the name of your own custom class.
@@ -425,10 +482,23 @@ to `'http authentication'`.
 Defaults to `'signed cookie'`.
 
 * `config.action_dispatch.encrypted_cookie_salt` sets the encrypted cookies salt
-value. Defaults to `'encrypted cookie'`.
+  value. Defaults to `'encrypted cookie'`.
 
 * `config.action_dispatch.encrypted_signed_cookie_salt` sets the signed
-encrypted cookies salt value. Defaults to `'signed encrypted cookie'`.
+  encrypted cookies salt value. Defaults to `'signed encrypted cookie'`.
+
+* `config.action_dispatch.authenticated_encrypted_cookie_salt` sets the
+  authenticated encrypted cookie salt. Defaults to `'authenticated encrypted
+  cookie'`.
+
+* `config.action_dispatch.encrypted_cookie_cipher` sets the cipher to be
+  used for encrypted cookies. This defaults to `"aes-256-gcm"`.
+
+* `config.action_dispatch.signed_cookie_digest` sets the digest to be
+  used for signed cookies. This defaults to `"SHA1"`.
+
+* `config.action_dispatch.cookies_rotations` allows rotating
+  secrets, ciphers, and digests for encrypted and signed cookies.
 
 * `config.action_dispatch.perform_deep_munge` configures whether `deep_munge`
   method should be performed on the parameters. See [Security Guide](security.html#unsafe-query-generation)
@@ -438,21 +508,23 @@ encrypted cookies salt value. Defaults to `'signed encrypted cookie'`.
 
   ```ruby
   config.action_dispatch.rescue_responses = {
-    'ActionController::RoutingError'              => :not_found,
-    'AbstractController::ActionNotFound'          => :not_found,
-    'ActionController::MethodNotAllowed'          => :method_not_allowed,
-    'ActionController::UnknownHttpMethod'         => :method_not_allowed,
-    'ActionController::NotImplemented'            => :not_implemented,
-    'ActionController::UnknownFormat'             => :not_acceptable,
-    'ActionController::InvalidAuthenticityToken'  => :unprocessable_entity,
-    'ActionController::InvalidCrossOriginRequest' => :unprocessable_entity,
-    'ActionDispatch::ParamsParser::ParseError'    => :bad_request,
-    'ActionController::BadRequest'                => :bad_request,
-    'ActionController::ParameterMissing'          => :bad_request,
-    'ActiveRecord::RecordNotFound'                => :not_found,
-    'ActiveRecord::StaleObjectError'              => :conflict,
-    'ActiveRecord::RecordInvalid'                 => :unprocessable_entity,
-    'ActiveRecord::RecordNotSaved'                => :unprocessable_entity
+    'ActionController::RoutingError'               => :not_found,
+    'AbstractController::ActionNotFound'           => :not_found,
+    'ActionController::MethodNotAllowed'           => :method_not_allowed,
+    'ActionController::UnknownHttpMethod'          => :method_not_allowed,
+    'ActionController::NotImplemented'             => :not_implemented,
+    'ActionController::UnknownFormat'              => :not_acceptable,
+    'ActionController::InvalidAuthenticityToken'   => :unprocessable_entity,
+    'ActionController::InvalidCrossOriginRequest'  => :unprocessable_entity,
+    'ActionDispatch::Http::Parameters::ParseError' => :bad_request,
+    'ActionController::BadRequest'                 => :bad_request,
+    'ActionController::ParameterMissing'           => :bad_request,
+    'Rack::QueryParser::ParameterTypeError'        => :bad_request,
+    'Rack::QueryParser::InvalidParameterError'     => :bad_request,
+    'ActiveRecord::RecordNotFound'                 => :not_found,
+    'ActiveRecord::StaleObjectError'               => :conflict,
+    'ActiveRecord::RecordInvalid'                  => :unprocessable_entity,
+    'ActiveRecord::RecordNotSaved'                 => :unprocessable_entity
   }
   ```
 
@@ -460,8 +532,6 @@ encrypted cookies salt value. Defaults to `'signed encrypted cookie'`.
 
 * `ActionDispatch::Callbacks.before` takes a block of code to run before the request.
 
-* `ActionDispatch::Callbacks.to_prepare` takes a block to run after `ActionDispatch::Callbacks.before`, but before the request. Runs for every request in `development` mode, but only once for `production` or environments with `cache_classes` set to `true`.
-
 * `ActionDispatch::Callbacks.after` takes a block of code to run after the request.
 
 ### Configuring Action View
@@ -506,10 +576,14 @@ encrypted cookies salt value. Defaults to `'signed encrypted cookie'`.
   error should be raised for missing translations.
 
 * `config.action_view.automatically_disable_submit_tag` determines whether
-  submit_tag should automatically disable on click, this defaults to `true`.
+  `submit_tag` should automatically disable on click, this defaults to `true`.
 
 * `config.action_view.debug_missing_translation` determines whether to wrap the missing translations key in a `<span>` tag or not. This defaults to `true`.
 
+* `config.action_view.form_with_generates_remote_forms` determines whether `form_with` generates remote forms or not. This defaults to `true`.
+
+* `config.action_view.form_with_generates_ids` determines whether `form_with` generates ids on inputs. This defaults to `true`.
+
 ### Configuring Action Mailer
 
 There are a number of settings available on `config.action_mailer`:
@@ -525,11 +599,11 @@ There are a number of settings available on `config.action_mailer`:
     * `:authentication` - If your mail server requires authentication, you need to specify the authentication type here. This is a symbol and one of `:plain`, `:login`, `:cram_md5`.
     * `:enable_starttls_auto` - Detects if STARTTLS is enabled in your SMTP server and starts to use it. It defaults to `true`.
     * `:openssl_verify_mode` - When using TLS, you can set how OpenSSL checks the certificate. This is useful if you need to validate a self-signed and/or a wildcard certificate. This can be one of the OpenSSL verify constants, `:none` or `:peer` -- or the constant directly `OpenSSL::SSL::VERIFY_NONE` or `OpenSSL::SSL::VERIFY_PEER`, respectively.
-    * `:ssl/:tls` - Enables the SMTP connection to use SMTP/TLS (SMTPS: SMTP over direct TLS connection).                                  
+    * `:ssl/:tls` - Enables the SMTP connection to use SMTP/TLS (SMTPS: SMTP over direct TLS connection).
 
 * `config.action_mailer.sendmail_settings` allows detailed configuration for the `sendmail` delivery method. It accepts a hash of options, which can include any of these options:
     * `:location` - The location of the sendmail executable. Defaults to `/usr/sbin/sendmail`.
-    * `:arguments` - The command line arguments. Defaults to `-i -t`.
+    * `:arguments` - The command line arguments. Defaults to `-i`.
 
 * `config.action_mailer.raise_delivery_errors` specifies whether to raise an error if email delivery cannot be completed. It defaults to `true`.
 
@@ -590,7 +664,7 @@ There are a few configuration options available in Active Support:
 
 * `config.active_support.bare` enables or disables the loading of `active_support/all` when booting Rails. Defaults to `nil`, which means `active_support/all` is loaded.
 
-* `config.active_support.test_order` sets the order that test cases are executed. Possible values are `:random` and `:sorted`. This option is set to `:random` in `config/environments/test.rb` in newly-generated applications. If you have an application that does not specify a `test_order`, it will default to `:sorted`, *until* Rails 5.0, when the default will become `:random`.
+* `config.active_support.test_order` sets the order in which the test cases are executed. Possible values are `:random` and `:sorted`. Defaults to `:random`.
 
 * `config.active_support.escape_html_entities_in_json` enables or disables the escaping of HTML entities in JSON serialization. Defaults to `true`.
 
@@ -598,8 +672,6 @@ There are a few configuration options available in Active Support:
 
 * `config.active_support.time_precision` sets the precision of JSON encoded time values. Defaults to `3`.
 
-* `ActiveSupport.halt_callback_chains_on_return_false` specifies whether Active Record and Active Model callback chains can be halted by returning `false` in a 'before' callback. When set to `false`, callback chains are halted only when explicitly done so with `throw(:abort)`. When set to `true`, callback chains are halted when a callback returns `false` (the previous behavior before Rails 5) and a deprecation warning is given. Defaults to `true` during the deprecation period. New Rails 5 apps generate an initializer file called `callback_terminator.rb` which sets the value to `false`. This file is *not* added when running `rails app:update`, so returning `false` will still work on older apps ported to Rails 5 and display a deprecation warning to prompt users to update their code.
-
 * `ActiveSupport::Logger.silencer` is set to `false` to disable the ability to silence logging in a block. The default is `true`.
 
 * `ActiveSupport::Cache::Store.logger` specifies the logger to use within cache store operations.
@@ -907,7 +979,7 @@ By default Rails ships with three environments: "development", "test", and "prod
 
 Imagine you have a server which mirrors the production environment but is only used for testing. Such a server is commonly called a "staging server". To define an environment called "staging" for this server, just create a file called `config/environments/staging.rb`. Please use the contents of any existing file in `config/environments` as a starting point and make the necessary changes from there.
 
-That environment is no different than the default ones, start a server with `rails server -e staging`, a console with `rails console staging`, `Rails.env.staging?` works, etc.
+That environment is no different than the default ones, start a server with `rails server -e staging`, a console with `rails console -e staging`, `Rails.env.staging?` works, etc.
 
 
 ### Deploy to a subdirectory (relative url root)
@@ -937,17 +1009,17 @@ Deploying your application using a reverse proxy has definite advantages over tr
 
 Many modern web servers can be used as a proxy server to balance third-party elements such as caching servers or application servers.
 
-One such application server you can use is [Unicorn](http://unicorn.bogomips.org/) to run behind a reverse proxy.
+One such application server you can use is [Unicorn](https://bogomips.org/unicorn/) to run behind a reverse proxy.
 
 In this case, you would need to configure the proxy server (NGINX, Apache, etc) to accept connections from your application server (Unicorn). By default Unicorn will listen for TCP connections on port 8080, but you can change the port or configure it to use sockets instead.
 
-You can find more information in the [Unicorn readme](http://unicorn.bogomips.org/README.html) and understand the [philosophy](http://unicorn.bogomips.org/PHILOSOPHY.html) behind it.
+You can find more information in the [Unicorn readme](https://bogomips.org/unicorn/README.html) and understand the [philosophy](https://bogomips.org/unicorn/PHILOSOPHY.html) behind it.
 
 Once you've configured the application server, you must proxy requests to it by configuring your web server appropriately. For example your NGINX config may include:
 
 ```
 upstream application_server {
-  server 0.0.0.0:8080
+  server 0.0.0.0:8080;
 }
 
 server {
@@ -969,7 +1041,7 @@ server {
 }
 ```
 
-Be sure to read the [NGINX documentation](http://nginx.org/en/docs/) for the most up-to-date information.
+Be sure to read the [NGINX documentation](https://nginx.org/en/docs/) for the most up-to-date information.
 
 
 Rails Environment Settings
@@ -991,7 +1063,7 @@ After loading the framework and any gems in your application, Rails turns to loa
 
 NOTE: You can use subfolders to organize your initializers if you like, because Rails will look into the whole file hierarchy from the initializers folder on down.
 
-TIP: If you have any ordering dependency in your initializers, you can control the load order through naming. Initializer files are loaded in alphabetical order by their path. For example, `01_critical.rb` will be loaded before `02_normal.rb`.
+TIP: While Rails supports numbering of initializer file names for load ordering purposes, a better technique is to place any code that need to load in a specific order within the same file. This reduces file name churn, makes dependencies more explicit, and can help surface new concepts within your application.
 
 Initialization events
 ---------------------
@@ -1155,7 +1227,7 @@ Below is a comprehensive list of all the initializers found in Rails in the orde
 
 * `finisher_hook`: Provides a hook for after the initialization of process of the application is complete, as well as running all the `config.after_initialize` blocks for the application, railties and engines.
 
-* `set_routes_reloader`: Configures Action Dispatch to reload the routes file using `ActionDispatch::Callbacks.to_prepare`.
+* `set_routes_reloader_hook`: Configures Action Dispatch to reload the routes file using `ActiveSupport::Callbacks.to_run`.
 
 * `disable_dependency_loading`: Disables the automatic dependency loading if the `config.eager_load` is set to `true`.
 
@@ -1172,7 +1244,7 @@ development:
   timeout: 5000
 ```
 
-Since the connection pooling is handled inside of Active Record by default, all application servers (Thin, mongrel, Unicorn etc.) should behave the same. The database connection pool is initially empty. As demand for connections increases it will create them until it reaches the connection pool limit.
+Since the connection pooling is handled inside of Active Record by default, all application servers (Thin, Puma, Unicorn etc.) should behave the same. The database connection pool is initially empty. As demand for connections increases it will create them until it reaches the connection pool limit.
 
 Any one request will check out a connection the first time it requires access to the database. At the end of the request it will check the connection back in. This means that the additional connection slot will be available again for the next request in the queue.
 
@@ -1193,21 +1265,25 @@ NOTE. If you are running in a multi-threaded environment, there could be a chanc
 Custom configuration
 --------------------
 
-You can configure your own code through the Rails configuration object with custom configuration. It works like this:
+You can configure your own code through the Rails configuration object with
+custom configuration under either the `config.x` namespace, or `config` directly.
+The key difference between these two is that you should be using `config.x` if you
+are defining _nested_ configuration (ex: `config.x.nested.nested.hi`), and just
+`config` for _single level_ configuration (ex: `config.hello`).
 
   ```ruby
-  config.payment_processing.schedule = :daily
-  config.payment_processing.retries  = 3
+  config.x.payment_processing.schedule = :daily
+  config.x.payment_processing.retries  = 3
   config.super_debugger = true
   ```
 
 These configuration points are then available through the configuration object:
 
   ```ruby
-  Rails.configuration.payment_processing.schedule # => :daily
-  Rails.configuration.payment_processing.retries  # => 3
-  Rails.configuration.super_debugger              # => true
-  Rails.configuration.super_debugger.not_set      # => nil
+  Rails.configuration.x.payment_processing.schedule # => :daily
+  Rails.configuration.x.payment_processing.retries  # => 3
+  Rails.configuration.x.payment_processing.not_set  # => nil
+  Rails.configuration.super_debugger                # => true
   ```
 
 You can also use `Rails::Application.config_for` to load whole configuration files:
@@ -1247,7 +1323,7 @@ know which pages it is allowed to index.
 
 Rails creates this file for you inside the `/public` folder. By default, it allows
 search engines to index all pages of your application. If you want to block
-indexing on all pages of you application, use this:
+indexing on all pages of your application, use this:
 
 ```
 User-agent: *
@@ -1266,14 +1342,14 @@ evented file system monitor to detect changes when `config.cache_classes` is
 
 ```ruby
 group :development do
-  gem 'listen', '~> 3.0.4'
+  gem 'listen', '>= 3.0.5', '< 3.2'
 end
 ```
 
 Otherwise, in every request Rails walks the application tree to check if
 anything has changed.
 
-On Linux and Mac OS X no additional gems are needed, but some are required
+On Linux and macOS no additional gems are needed, but some are required
 [for *BSD](https://github.com/guard/listen#on-bsd) and
 [for Windows](https://github.com/guard/listen#on-windows).
 
diff --git a/guides/source/contributing_to_ruby_on_rails.md b/guides/source/contributing_to_ruby_on_rails.md
index ba8d085f79..967c992c05 100644
--- a/guides/source/contributing_to_ruby_on_rails.md
+++ b/guides/source/contributing_to_ruby_on_rails.md
@@ -13,9 +13,9 @@ After reading this guide, you will know:
 * How to contribute to the Ruby on Rails documentation.
 * How to contribute to the Ruby on Rails code.
 
-Ruby on Rails is not "someone else's framework." Over the years, hundreds of people have contributed to Ruby on Rails ranging from a single character to massive architectural changes or significant documentation - all with the goal of making Ruby on Rails better for everyone. Even if you don't feel up to writing code or documentation yet, there are a variety of other ways that you can contribute, from reporting issues to testing patches.
+Ruby on Rails is not "someone else's framework." Over the years, thousands of people have contributed to Ruby on Rails ranging from a single character to massive architectural changes or significant documentation - all with the goal of making Ruby on Rails better for everyone. Even if you don't feel up to writing code or documentation yet, there are a variety of other ways that you can contribute, from reporting issues to testing patches.
 
-As mentioned in [Rails
+As mentioned in [Rails'
 README](https://github.com/rails/rails/blob/master/README.md), everyone interacting in Rails and its sub-projects' codebases, issue trackers, chat rooms, and mailing lists is expected to follow the Rails [code of conduct](http://rubyonrails.org/conduct/).
 
 --------------------------------------------------------------------------------
@@ -40,7 +40,9 @@ Then, don't get your hopes up! Unless you have a "Code Red, Mission Critical, th
 Having a way to reproduce your issue will be very helpful for others to help confirm, investigate and ultimately fix your issue. You can do this by providing an executable test case. To make this process easier, we have prepared several bug report templates for you to use as a starting point:
 
 * Template for Active Record (models, database) issues: [gem](https://github.com/rails/rails/blob/master/guides/bug_report_templates/active_record_gem.rb) / [master](https://github.com/rails/rails/blob/master/guides/bug_report_templates/active_record_master.rb)
+* Template for testing Active Record (migration) issues: [gem](https://github.com/rails/rails/blob/master/guides/bug_report_templates/active_record_migrations_gem.rb) / [master](https://github.com/rails/rails/blob/master/guides/bug_report_templates/active_record_migrations_master.rb)
 * Template for Action Pack (controllers, routing) issues: [gem](https://github.com/rails/rails/blob/master/guides/bug_report_templates/action_controller_gem.rb) / [master](https://github.com/rails/rails/blob/master/guides/bug_report_templates/action_controller_master.rb)
+* Template for Active Job issues: [gem](https://github.com/rails/rails/blob/master/guides/bug_report_templates/active_job_gem.rb) / [master](https://github.com/rails/rails/blob/master/guides/bug_report_templates/active_job_master.rb)
 * Generic template for other issues: [gem](https://github.com/rails/rails/blob/master/guides/bug_report_templates/generic_gem.rb) / [master](https://github.com/rails/rails/blob/master/guides/bug_report_templates/generic_master.rb)
 
 These templates include the boilerplate code to set up a test case against either a released version of Rails (`*_gem.rb`) or edge Rails (`*_master.rb`).
@@ -65,7 +67,7 @@ can expect it to be marked "invalid" as soon as it's reviewed.
 Sometimes, the line between 'bug' and 'feature' is a hard one to draw.
 Generally, a feature is anything that adds new behavior, while a bug is
 anything that causes incorrect behavior. Sometimes,
-the core team will have to make a judgement call. That said, the distinction
+the core team will have to make a judgment call. That said, the distinction
 generally just affects which release your patch will get in to; we love feature
 submissions! They just won't get backported to maintenance branches.
 
@@ -82,7 +84,9 @@ discussions new features require.
 Helping to Resolve Existing Issues
 ----------------------------------
 
-As a next step beyond reporting issues, you can help the core team resolve existing issues. If you check the [issues list](https://github.com/rails/rails/issues) in GitHub Issues, you'll find lots of issues already requiring attention. What can you do for these? Quite a bit, actually:
+As a next step beyond reporting issues, you can help the core team resolve existing ones by providing feedback about them. If you are new to Rails core development, that might be a great way to walk your first steps, you'll get familiar with the code base and the processes.
+
+If you check the [issues list](https://github.com/rails/rails/issues) in GitHub Issues, you'll find lots of issues already requiring attention. What can you do for these? Quite a bit, actually:
 
 ### Verifying Bug Reports
 
@@ -90,19 +94,19 @@ For starters, it helps just to verify bug reports. Can you reproduce the reporte
 
 If an issue is very vague, can you help narrow it down to something more specific? Maybe you can provide additional information to help reproduce a bug, or help by eliminating needless steps that aren't required to demonstrate the problem.
 
-If you find a bug report without a test, it's very useful to contribute a failing test. This is also a great way to get started exploring the source code: looking at the existing test files will teach you how to write more tests. New tests are best contributed in the form of a patch, as explained later on in the "Contributing to the Rails Code" section.
+If you find a bug report without a test, it's very useful to contribute a failing test. This is also a great way to get started exploring the source code: looking at the existing test files will teach you how to write more tests. New tests are best contributed in the form of a patch, as explained later on in the "[Contributing to the Rails Code](#contributing-to-the-rails-code)" section.
 
 Anything you can do to make bug reports more succinct or easier to reproduce helps folks trying to write code to fix those bugs - whether you end up writing the code yourself or not.
 
 ### Testing Patches
 
-You can also help out by examining pull requests that have been submitted to Ruby on Rails via GitHub. To apply someone's changes you need first to create a dedicated branch:
+You can also help out by examining pull requests that have been submitted to Ruby on Rails via GitHub. In order to apply someone's changes, you need to first create a dedicated branch:
 
 ```bash
 $ git checkout -b testing_branch
 ```
 
-Then you can use their remote branch to update your codebase. For example, let's say the GitHub user JohnSmith has forked and pushed to a topic branch "orange" located at https://github.com/JohnSmith/rails.
+Then, you can use their remote branch to update your codebase. For example, let's say the GitHub user JohnSmith has forked and pushed to a topic branch "orange" located at https://github.com/JohnSmith/rails.
 
 ```bash
 $ git remote add JohnSmith https://github.com/JohnSmith/rails.git
@@ -130,35 +134,24 @@ learn about Ruby on Rails, and the API, which serves as a reference.
 
 You can help improve the Rails guides by making them more coherent, consistent or readable, adding missing information, correcting factual errors, fixing typos, or bringing them up to date with the latest edge Rails.
 
-You can either open a pull request to [Rails](https://github.com/rails/rails) or
-ask the [Rails core team](http://rubyonrails.org/community/#core) for commit access on
-docrails if you contribute regularly.
-Please do not open pull requests in docrails, if you'd like to get feedback on your
-change, ask for it in [Rails](https://github.com/rails/rails) instead.
-
-Docrails is merged with master regularly, so you are effectively editing the Ruby on Rails documentation.
-
-If you are unsure of the documentation changes, you can create an issue in the [Rails](https://github.com/rails/rails/issues) issues tracker on GitHub.
+To do so, open a pull request to [Rails](https://github.com/rails/rails) on GitHub.
 
 When working with documentation, please take into account the [API Documentation Guidelines](api_documentation_guidelines.html) and the [Ruby on Rails Guides Guidelines](ruby_on_rails_guides_guidelines.html).
 
-NOTE: As explained earlier, ordinary code patches should have proper documentation coverage. Docrails is only used for isolated documentation improvements.
-
 NOTE: To help our CI servers you should add [ci skip] to your documentation commit message to skip build on that commit. Please remember to use it for commits containing only documentation changes.
 
-WARNING: Docrails has a very strict policy: no code can be touched whatsoever, no matter how trivial or small the change. Only RDoc and guides can be edited via docrails. Also, CHANGELOGs should never be edited in docrails.
-
 Translating Rails Guides
 ------------------------
 
-We are happy to have people volunteer to translate the Rails guides into their own language.
-If you want to translate the Rails guides in your own language, follows these steps:
+We are happy to have people volunteer to translate the Rails guides. Just follow these steps:
 
-* Fork the project (rails/rails).
+* Fork https://github.com/rails/rails.
 * Add a source folder for your own language, for example: *guides/source/it-IT* for Italian.
 * Copy the contents of *guides/source* into your own language directory and translate them.
 * Do NOT translate the HTML files, as they are automatically generated.
 
+Note that translations are not submitted to the Rails repository. As detailed above, your work happens in a fork. This is so because in practice documentation maintenance via patches is only sustainable in English.
+
 To generate the guides in HTML format cd into the *guides* directory then run (eg. for it-IT):
 
 ```bash
@@ -173,11 +166,11 @@ NOTE: The instructions are for Rails > 4. The Redcarpet Gem doesn't work with JR
 Translation efforts we know about (various versions):
 
 * **Italian**: [https://github.com/rixlabs/docrails](https://github.com/rixlabs/docrails)
-* **Spanish**: [http://wiki.github.com/gramos/docrails](http://wiki.github.com/gramos/docrails)
-* **Polish**: [https://github.com/apohllo/docrails/tree/master](https://github.com/apohllo/docrails/tree/master)
+* **Spanish**: [https://github.com/gramos/docrails/wiki](https://github.com/gramos/docrails/wiki)
+* **Polish**: [https://github.com/apohllo/docrails](https://github.com/apohllo/docrails)
 * **French** : [https://github.com/railsfrance/docrails](https://github.com/railsfrance/docrails)
 * **Czech** : [https://github.com/rubyonrails-cz/docrails/tree/czech](https://github.com/rubyonrails-cz/docrails/tree/czech)
-* **Turkish** : [https://github.com/ujk/docrails/tree/master](https://github.com/ujk/docrails/tree/master)
+* **Turkish** : [https://github.com/ujk/docrails](https://github.com/ujk/docrails)
 * **Korean** : [https://github.com/rorlakr/rails-guides](https://github.com/rorlakr/rails-guides)
 * **Simplified Chinese** : [https://github.com/ruby-china/guides](https://github.com/ruby-china/guides)
 * **Traditional Chinese** : [https://github.com/docrails-tw/guides](https://github.com/docrails-tw/guides)
@@ -193,7 +186,7 @@ To move on from submitting bugs to helping resolve existing issues or contributi
 
 #### The Easy Way
 
-The easiest and recommended way to get a development environment ready to hack is to use the [Rails development box](https://github.com/rails/rails-dev-box).
+The easiest and recommended way to get a development environment ready to hack is to use the [rails-dev-box](https://github.com/rails/rails-dev-box).
 
 #### The Hard Way
 
@@ -268,33 +261,24 @@ The above are guidelines - please use your best judgment in using them.
 
 ### Benchmark Your Code
 
-If your change has an impact on the performance of Rails, please use the
-[benchmark-ips](https://github.com/evanphx/benchmark-ips) gem to provide
-benchmark results for comparison.
-
-Here's an example of using benchmark-ips:
-
-```ruby
-require 'benchmark/ips'
-
-Benchmark.ips do |x|
-  x.report('addition') { 1 + 2 }
-  x.report('addition with send') { 1.send(:+, 2) }
-end
-```
-
-This will generate a report with the following information:
-
-```
-Calculating -------------------------------------
-            addition   132.013k i/100ms
-  addition with send   125.413k i/100ms
--------------------------------------------------
-            addition      9.677M (± 1.7%) i/s -     48.449M
-  addition with send      6.794M (± 1.1%) i/s -     33.987M
-```
-
-Please see the benchmark/ips [README](https://github.com/evanphx/benchmark-ips/blob/master/README.md) for more information.
+For changes that might have an impact on performance, please benchmark your
+code and measure the impact. Please share the benchmark script you used as well
+as the results. You should consider including this information in your commit
+message, which allows future contributors to easily verify your findings and
+determine if they are still relevant. (For example, future optimizations in the
+Ruby VM might render certain optimizations unnecessary.)
+
+It is very easy to make an optimization that improves performance for a
+specific scenario you care about but regresses on other common cases.
+Therefore, you should test your change against a list of representative
+scenarios. Ideally, they should be based on real-world scenarios extracted
+from production applications.
+
+You can use the [benchmark template](https://github.com/rails/rails/blob/master/guides/bug_report_templates/benchmark.rb)
+as a starting point. It includes the boilerplate code to setup a benchmark
+using the [benchmark-ips](https://github.com/evanphx/benchmark-ips) gem. The
+template is designed for testing relatively self-contained changes that can be
+inlined into the script.
 
 ### Running Tests
 
@@ -342,10 +326,12 @@ file.
 
 #### Testing Active Record
 
-First, create the databases you'll need. For MySQL and PostgreSQL,
-running the SQL statements `create database activerecord_unittest` and
-`create database activerecord_unittest2` is sufficient. This is not
-necessary for SQLite3.
+First, create the databases you'll need. You can find a list of the required
+table names, usernames, and passwords in `activerecord/test/config.example.yml`.
+
+For MySQL and PostgreSQL, running the SQL statements `create database
+activerecord_unittest` and `create database activerecord_unittest2` is
+sufficient. This is not necessary for SQLite3.
 
 This is how you run the Active Record test suite only for SQLite3:
 
@@ -423,16 +409,6 @@ examples or multiple paragraphs. Otherwise, it's best to make a new paragraph.
 
 Some changes require the dependencies to be upgraded. In these cases make sure you run `bundle update` to get the right version of the dependency and commit the `Gemfile.lock` file within your changes.
 
-### Sanity Check
-
-You should not be the only person who looks at the code before you submit it.
-If you know someone else who uses Rails, try asking them if they'll check out
-your work. If you don't know anyone else using Rails, try hopping into the IRC
-room or posting about your idea to the rails-core mailing list. Doing this in
-private before you push a patch out publicly is the "smoke test" for a patch:
-if you can't convince one other developer of the beauty of your code, you’re
-unlikely to convince the core team either.
-
 ### Commit Your Changes
 
 When you're happy with the code on your computer, you need to commit the changes to Git:
@@ -506,7 +482,7 @@ Navigate to the Rails [GitHub repository](https://github.com/rails/rails) and pr
 Add the new remote to your local repository on your local machine:
 
 ```bash
-$ git remote add mine https://github.com:<your user name>/rails.git
+$ git remote add mine https://github.com/<your user name>/rails.git
 ```
 
 Push to your remote:
@@ -580,7 +556,7 @@ is the open source life.
 
 If it's been over a week, and you haven't heard anything, you might want to try
 and nudge things along. You can use the [rubyonrails-core mailing
-list](http://groups.google.com/group/rubyonrails-core/) for this. You can also
+list](https://groups.google.com/forum/#!forum/rubyonrails-core) for this. You can also
 leave another comment on the pull request.
 
 While you're waiting for feedback on your pull request, open up a few other
@@ -677,7 +653,7 @@ $ git format-patch master --stdout > ~/my_changes.patch
 Switch over to the target branch and apply your changes:
 
 ```bash
-$ git checkout -b my_backport_branch 3-2-stable
+$ git checkout -b my_backport_branch 4-2-stable
 $ git apply ~/my_changes.patch
 ```
 
@@ -690,4 +666,4 @@ And then... think about your next contribution!
 Rails Contributors
 ------------------
 
-All contributions, either via master or docrails, get credit in [Rails Contributors](http://contributors.rubyonrails.org).
+All contributions get credit in [Rails Contributors](http://contributors.rubyonrails.org).
diff --git a/guides/source/credits.html.erb b/guides/source/credits.html.erb
index 511d76041b..5adbd12ac0 100644
--- a/guides/source/credits.html.erb
+++ b/guides/source/credits.html.erb
@@ -22,7 +22,7 @@ Ruby on Rails Guides: Credits
 <h3 class="section">Rails Guides Designers</h3>
 
 <%= author('Jason Zimdars', 'jz') do %>
-  Jason Zimdars is an experienced creative director and web designer who has lead UI and UX design for numerous websites and web applications. You can see more of his design and writing at <a href="http://www.thinkcage.com/">Thinkcage.com</a> or follow him on <a href="http://twitter.com/JZ">Twitter</a>.
+  Jason Zimdars is an experienced creative director and web designer who has lead UI and UX design for numerous websites and web applications. You can see more of his design and writing at <a href="http://www.thinkcage.com/">Thinkcage.com</a> or follow him on <a href="https://twitter.com/jasonzimdars">Twitter</a>.
 <% end %>
 
 <h3 class="section">Rails Guides Authors</h3>
@@ -32,7 +32,7 @@ Ruby on Rails Guides: Credits
 <% end %>
 
 <%= author('Oscar Del Ben', 'oscardelben', 'oscardelben.jpg') do %>
-Oscar Del Ben is a software engineer at <a href="http://www.wildfireapp.com/">Wildfire</a>. He's a regular open source contributor (<a href="https://github.com/oscardelben">GitHub account</a>) and tweets regularly at <a href="https://twitter.com/oscardelben">@oscardelben</a>.
+Oscar Del Ben is a software engineer at <a href="http://www.businessinsider.com/google-buys-wildfire-2012-8">Wildfire</a>. He's a regular open source contributor (<a href="https://github.com/oscardelben">GitHub account</a>) and tweets regularly at <a href="https://twitter.com/oscardelben">@oscardelben</a>.
   <% end %>
 
 <%= author('Frederick Cheung', 'fcheung') do %>
diff --git a/guides/source/debugging_rails_applications.md b/guides/source/debugging_rails_applications.md
index f0d0f9753a..07c78be3db 100644
--- a/guides/source/debugging_rails_applications.md
+++ b/guides/source/debugging_rails_applications.md
@@ -162,41 +162,41 @@ class ArticlesController < ApplicationController
   # ...
 
   def create
-    @article = Article.new(params[:article])
+    @article = Article.new(article_params)
     logger.debug "New article: #{@article.attributes.inspect}"
     logger.debug "Article should be valid: #{@article.valid?}"
 
     if @article.save
-      flash[:notice] =  'Article was successfully created.'
       logger.debug "The article was saved and now the user is going to be redirected..."
-      redirect_to(@article)
+      redirect_to @article, notice: 'Article was successfully created.'
     else
-      render action: "new"
+      render :new
     end
   end
 
   # ...
+
+  private
+    def article_params
+      params.require(:article).permit(:title, :body, :published)
+    end
 end
 ```
 
 Here's an example of the log generated when this controller action is executed:
 
 ```
-Processing ArticlesController#create (for 127.0.0.1 at 2008-09-08 11:52:54) [POST]
-  Session ID: BAh7BzoMY3NyZl9pZCIlMDY5MWU1M2I1ZDRjODBlMzkyMWI1OTg2NWQyNzViZjYiCmZsYXNoSUM6J0FjdGl
-vbkNvbnRyb2xsZXI6OkZsYXNoOjpGbGFzaEhhc2h7AAY6CkB1c2VkewA=--b18cd92fba90eacf8137e5f6b3b06c4d724596a4
-  Parameters: {"commit"=>"Create", "article"=>{"title"=>"Debugging Rails",
- "body"=>"I'm learning how to print in logs!!!", "published"=>"0"},
- "authenticity_token"=>"2059c1286e93402e389127b1153204e0d1e275dd", "action"=>"create", "controller"=>"articles"}
-New article: {"updated_at"=>nil, "title"=>"Debugging Rails", "body"=>"I'm learning how to print in logs!!!",
- "published"=>false, "created_at"=>nil}
+Started POST "/articles" for 127.0.0.1 at 2017-08-20 20:53:10 +0900
+Processing by ArticlesController#create as HTML
+  Parameters: {"utf8"=>"✓", "authenticity_token"=>"xhuIbSBFytHCE1agHgvrlKnSVIOGD6jltW2tO+P6a/ACjQ3igjpV4OdbsZjIhC98QizWH9YdKokrqxBCJrtoqQ==", "article"=>{"title"=>"Debugging Rails", "body"=>"I'm learning how to print in logs!!!", "published"=>"0"}, "commit"=>"Create Article"}
+New article: {"id"=>nil, "title"=>"Debugging Rails", "body"=>"I'm learning how to print in logs!!!", "published"=>false, "created_at"=>nil, "updated_at"=>nil}
 Article should be valid: true
-  Article Create (0.000443)   INSERT INTO "articles" ("updated_at", "title", "body", "published",
- "created_at") VALUES('2008-09-08 14:52:54', 'Debugging Rails',
- 'I''m learning how to print in logs!!!', 'f', '2008-09-08 14:52:54')
+   (0.1ms)  BEGIN
+  SQL (0.4ms)  INSERT INTO "articles" ("title", "body", "published", "created_at", "updated_at") VALUES ($1, $2, $3, $4, $5) RETURNING "id"  [["title", "Debugging Rails"], ["body", "I'm learning how to print in logs!!!"], ["published", "f"], ["created_at", "2017-08-20 11:53:10.010435"], ["updated_at", "2017-08-20 11:53:10.010435"]]
+   (0.3ms)  COMMIT
 The article was saved and now the user is going to be redirected...
-Redirected to # Article:0x20af760>
-Completed in 0.01224 (81 reqs/sec) | DB: 0.00044 (3%) | 302 Found [http://localhost/articles]
+Redirected to http://localhost:3000/articles/1
+Completed 302 Found in 4ms (ActiveRecord: 0.8ms)
 ```
 
 Adding extra logging like this makes it easy to search for unexpected or unusual behavior in your logs. If you add extra logging, be sure to make sensible use of log levels to avoid filling your production logs with useless trivia.
@@ -313,7 +313,7 @@ For example:
 
 ```bash
 => Booting Puma
-=> Rails 5.0.0 application starting in development on http://0.0.0.0:3000
+=> Rails 5.1.0 application starting in development on http://0.0.0.0:3000
 => Run `rails server -h` for more startup options
 Puma starting in single mode...
 * Version 3.4.0 (ruby 2.3.1-p112), codename: Owl Bowl Brawl
@@ -401,7 +401,7 @@ To see the previous ten lines you should type `list-` (or `l-`).
    7      byebug
    8      @articles = Article.find_recent
    9
-   10      respond_to do |format|
+   10     respond_to do |format|
 ```
 
 This way you can move inside the file and see the code above the line where you
@@ -445,11 +445,11 @@ then `backtrace` will supply the answer.
 --> #0  ArticlesController.index
       at /PathToProject/app/controllers/articles_controller.rb:8
     #1  ActionController::BasicImplicitRender.send_action(method#String, *args#Array)
-      at /PathToGems/actionpack-5.0.0/lib/action_controller/metal/basic_implicit_render.rb:4
+      at /PathToGems/actionpack-5.1.0/lib/action_controller/metal/basic_implicit_render.rb:4
     #2  AbstractController::Base.process_action(action#NilClass, *args#Array)
-      at /PathToGems/actionpack-5.0.0/lib/abstract_controller/base.rb:181
+      at /PathToGems/actionpack-5.1.0/lib/abstract_controller/base.rb:181
     #3  ActionController::Rendering.process_action(action, *args)
-      at /PathToGems/actionpack-5.0.0/lib/action_controller/metal/rendering.rb:30
+      at /PathToGems/actionpack-5.1.0/lib/action_controller/metal/rendering.rb:30
 ...
 ```
 
@@ -461,7 +461,7 @@ context.
 ```
 (byebug) frame 2
 
-[176, 185] in /PathToGems/actionpack-5.0.0/lib/abstract_controller/base.rb
+[176, 185] in /PathToGems/actionpack-5.1.0/lib/abstract_controller/base.rb
    176:       # is the intended way to override action dispatching.
    177:       #
    178:       # Notice that the first argument is the method to be dispatched
@@ -540,8 +540,8 @@ command later in this guide).
    7       byebug
    8       @articles = Article.find_recent
    9
-=> 10       respond_to do |format|
-   11         format.html # index.html.erb
+=> 10      respond_to do |format|
+   11        format.html # index.html.erb
    12        format.json { render json: @articles }
    13      end
    14    end
@@ -606,7 +606,6 @@ You can also inspect for an object method this way:
 @new_record = true
 @readonly = false
 @transaction_state = nil
-@txn = nil
 ```
 
 You can also use `display` to start watching variables. This is a good way of
@@ -677,13 +676,13 @@ Ruby instruction to be executed -- in this case, Active Support's `week` method.
 ```
 (byebug) step
 
-[49, 58] in /PathToGems/activesupport-5.0.0/lib/active_support/core_ext/numeric/time.rb
+[49, 58] in /PathToGems/activesupport-5.1.0/lib/active_support/core_ext/numeric/time.rb
    49:
    50:   # Returns a Duration instance matching the number of weeks provided.
    51:   #
    52:   #   2.weeks # => 14 days
    53:   def weeks
-=> 54:     ActiveSupport::Duration.new(self * 7.days, [[:days, self * 7]])
+=> 54:     ActiveSupport::Duration.weeks(self)
    55:   end
    56:   alias :week :weeks
    57:
@@ -946,16 +945,10 @@ development that will end your tailing of development.log. Have all information
 about your Rails app requests in the browser — in the Developer Tools panel.
 Provides insight to db/rendering/total times, parameter list, rendered views and
 more.
+* [Pry](https://github.com/pry/pry) An IRB alternative and runtime developer console.
 
 References
 ----------
 
-* [ruby-debug Homepage](http://bashdb.sourceforge.net/ruby-debug/home-page.html)
-* [debugger Homepage](https://github.com/cldwalker/debugger)
 * [byebug Homepage](https://github.com/deivid-rodriguez/byebug)
 * [web-console Homepage](https://github.com/rails/web-console)
-* [Article: Debugging a Rails application with ruby-debug](http://www.sitepoint.com/debug-rails-app-ruby-debug/)
-* [Ryan Bates' debugging ruby (revised) screencast](http://railscasts.com/episodes/54-debugging-ruby-revised)
-* [Ryan Bates' stack trace screencast](http://railscasts.com/episodes/24-the-stack-trace)
-* [Ryan Bates' logger screencast](http://railscasts.com/episodes/56-the-logger)
-* [Debugging with ruby-debug](http://bashdb.sourceforge.net/ruby-debug.html)
diff --git a/guides/source/development_dependencies_install.md b/guides/source/development_dependencies_install.md
index cc24e6f666..50274d700b 100644
--- a/guides/source/development_dependencies_install.md
+++ b/guides/source/development_dependencies_install.md
@@ -21,24 +21,25 @@ The easiest and recommended way to get a development environment ready to hack i
 The Hard Way
 ------------
 
-In case you can't use the Rails development box, see section below, these are the steps to manually build a development box for Ruby on Rails core development.
+In case you can't use the Rails development box, see the steps below to manually
+build a development box for Ruby on Rails core development.
 
 ### Install Git
 
-Ruby on Rails uses Git for source code control. The [Git homepage](http://git-scm.com/) has installation instructions. There are a variety of resources on the net that will help you get familiar with Git:
+Ruby on Rails uses Git for source code control. The [Git homepage](https://git-scm.com/) has installation instructions. There are a variety of resources on the net that will help you get familiar with Git:
 
-* [Try Git course](http://try.github.io/) is an interactive course that will teach you the basics.
-* The [official Documentation](http://git-scm.com/documentation) is pretty comprehensive and also contains some videos with the basics of Git.
-* [Everyday Git](http://schacon.github.io/git/everyday.html) will teach you just enough about Git to get by.
-* [GitHub](http://help.github.com) offers links to a variety of Git resources.
-* [Pro Git](http://git-scm.com/book) is an entire book about Git with a Creative Commons license.
+* [Try Git course](https://try.github.io/) is an interactive course that will teach you the basics.
+* The [official Documentation](https://git-scm.com/documentation) is pretty comprehensive and also contains some videos with the basics of Git.
+* [Everyday Git](https://schacon.github.io/git/everyday.html) will teach you just enough about Git to get by.
+* [GitHub](https://help.github.com/) offers links to a variety of Git resources.
+* [Pro Git](https://git-scm.com/book) is an entire book about Git with a Creative Commons license.
 
 ### Clone the Ruby on Rails Repository
 
 Navigate to the folder where you want the Ruby on Rails source code (it will create its own `rails` subdirectory) and run:
 
 ```bash
-$ git clone git://github.com/rails/rails.git
+$ git clone https://github.com/rails/rails.git
 $ cd rails
 ```
 
@@ -46,7 +47,7 @@ $ cd rails
 
 The test suite must pass with any submitted code. No matter whether you are writing a new patch, or evaluating someone else's, you need to be able to run the tests.
 
-Install first SQLite3 and its development files for the `sqlite3` gem. Mac OS X
+Install first SQLite3 and its development files for the `sqlite3` gem. On macOS
 users are done with:
 
 ```bash
@@ -62,7 +63,7 @@ $ sudo apt-get install sqlite3 libsqlite3-dev
 If you are on Fedora or CentOS, you're done with
 
 ```bash
-$ sudo yum install sqlite3 sqlite3-devel
+$ sudo yum install libsqlite3x libsqlite3x-devel
 ```
 
 If you are on Arch Linux, you will need to run:
@@ -79,7 +80,7 @@ For FreeBSD users, you're done with:
 
 Or compile the `databases/sqlite3` port.
 
-Get a recent version of [Bundler](http://bundler.io/)
+Get a recent version of [Bundler](https://bundler.io/)
 
 ```bash
 $ gem install bundler
@@ -96,7 +97,7 @@ This command will install all dependencies except the MySQL and PostgreSQL Ruby
 
 NOTE: If you would like to run the tests that use memcached, you need to ensure that you have it installed and running.
 
-You can use [Homebrew](http://brew.sh/) to install memcached on OS X:
+You can use [Homebrew](https://brew.sh/) to install memcached on macOS:
 
 ```bash
 $ brew install memcached
@@ -162,6 +163,10 @@ $ cd actionpack
 $ bundle exec ruby -Itest path/to/test.rb -n test_name
 ```
 
+### Railties Setup
+
+Some Railties tests depend on a JavaScript runtime environment, such as having [Node.js](https://nodejs.org/) installed.
+
 ### Active Record Setup
 
 Active Record's test suite runs three times: once for SQLite3, once for MySQL, and once for PostgreSQL. We are going to see now how to set up the environment for them.
@@ -177,7 +182,7 @@ The Active Record test suite requires a custom config file: `activerecord/test/c
 To be able to run the suite for MySQL and PostgreSQL we need their gems. Install
 first the servers, their client libraries, and their development files.
 
-On OS X, you can run:
+On macOS, you can run:
 
 ```bash
 $ brew install mysql
@@ -186,7 +191,7 @@ $ brew install postgresql
 
 Follow the instructions given by Homebrew to start these.
 
-In Ubuntu just run:
+On Ubuntu, just run:
 
 ```bash
 $ sudo apt-get install mysql-server libmysqlclient-dev
@@ -256,35 +261,118 @@ with your development account, on Linux or BSD, you just have to run:
 $ sudo -u postgres createuser --superuser $USER
 ```
 
-and for OS X:
+and for macOS:
 
 ```bash
 $ createuser --superuser $USER
 ```
 
-Then you need to create the test databases with
+Then, you need to create the test databases with:
 
 ```bash
 $ cd activerecord
 $ bundle exec rake db:postgresql:build
 ```
 
-It is possible to build databases for both PostgreSQL and MySQL with
+It is possible to build databases for both PostgreSQL and MySQL with:
 
 ```bash
 $ cd activerecord
 $ bundle exec rake db:create
 ```
 
-You can cleanup the databases using
+You can cleanup the databases using:
 
 ```bash
 $ cd activerecord
 $ bundle exec rake db:drop
 ```
 
-NOTE: Using the rake task to create the test databases ensures they have the correct character set and collation.
+NOTE: Using the Rake task to create the test databases ensures they have the correct character set and collation.
 
 NOTE: You'll see the following warning (or localized warning) during activating HStore extension in PostgreSQL 9.1.x or earlier: "WARNING: => is deprecated as an operator".
 
 If you're using another database, check the file `activerecord/test/config.yml` or `activerecord/test/config.example.yml` for default connection information. You can edit `activerecord/test/config.yml` to provide different credentials on your machine if you must, but obviously you should not push any such changes back to Rails.
+
+### Action Cable Setup
+
+Action Cable uses Redis as its default subscriptions adapter ([read more](action_cable_overview.html#broadcasting)). Thus, in order to have Action Cable's tests passing you need to install and have Redis running.
+
+#### Install Redis From Source
+
+Redis' documentation discourage installations with package managers as those are usually outdated. Installing from source and bringing the server up is straight forward and well documented on [Redis' documentation](https://redis.io/download#installation).
+
+#### Install Redis From Package Manager
+
+On macOS, you can run:
+
+```bash
+$ brew install redis
+```
+
+Follow the instructions given by Homebrew to start these.
+
+On Ubuntu, just run:
+
+```bash
+$ sudo apt-get install redis-server
+```
+
+On Fedora or CentOS (requires EPEL enabled), just run:
+
+```bash
+$ sudo yum install redis
+```
+
+If you are running Arch Linux, just run:
+
+```bash
+$ sudo pacman -S redis
+$ sudo systemctl start redis
+```
+
+FreeBSD users will have to run the following:
+
+```bash
+# portmaster databases/redis
+```
+
+### Active Storage Setup
+
+When working on Active Storage, it is important to note that you need to
+install its JavaScript dependencies while working on that section of the
+codebase. In order to install these dependencies, it is necessary to
+have Yarn, a Node.js package manager, available on your system. A
+prerequisite for installing this package manager is that
+[Node.js](https://nodejs.org) is installed.
+
+
+On macOS, you can run:
+
+```bash
+brew install yarn
+```
+
+On Ubuntu, you can run:
+
+```bash
+curl -sS https://dl.yarnpkg.com/debian/pubkey.gpg | sudo apt-key add -
+echo "deb https://dl.yarnpkg.com/debian/ stable main" | sudo tee /etc/apt/sources.list.d/yarn.list
+
+sudo apt-get update && sudo apt-get install yarn
+```
+
+On Fedora or CentOS, just run:
+
+```bash
+sudo wget https://dl.yarnpkg.com/rpm/yarn.repo -O /etc/yum.repos.d/yarn.repo
+
+sudo yum install yarn
+```
+
+Finally, after installing Yarn, you will need to run the following
+command inside of the `activestorage` directory to install the dependencies:
+
+```bash
+yarn install
+```
diff --git a/guides/source/documents.yaml b/guides/source/documents.yaml
index a06a53b250..5cddf79eeb 100644
--- a/guides/source/documents.yaml
+++ b/guides/source/documents.yaml
@@ -72,7 +72,7 @@
       url: active_support_core_extensions.html
       description: This guide documents the Ruby core extensions defined in Active Support.
     -
-      name: Rails Internationalization API
+      name: Rails Internationalization (I18n) API
       url: i18n.html
       description: This guide covers how to add internationalization to your applications. Your application will be able to translate content to different languages, change pluralization rules, use correct date formats for each country, and so on.
     -
@@ -84,10 +84,13 @@
       url: active_job_basics.html
       description: This guide provides you with all you need to get started creating, enqueuing, and executing background jobs.
     -
+      name: Active Storage Overview
+      url: active_storage_overview.html
+      description: This guide covers how to attach files to your Active Record models.
+    -
       name: Testing Rails Applications
-      work_in_progress: true
       url: testing.html
-      description: This is a rather comprehensive guide to the various testing facilities in Rails. It covers everything from 'What is a test?' to the testing APIs. Enjoy.
+      description: This is a rather comprehensive guide to the various testing facilities in Rails. It covers everything from 'What is a test?' to Integration Testing. Enjoy.
     -
       name: Securing Rails Applications
       url: security.html
@@ -101,11 +104,11 @@
       url: configuring.html
       description: This guide covers the basic configuration settings for a Rails application.
     -
-      name: Rails Command Line Tools and Rake Tasks
+      name: The Rails Command Line
       url: command_line.html
-      description: This guide covers the command line tools and rake tasks provided by Rails.
+      description: This guide covers the command line tools provided by Rails.
     -
-      name: Asset Pipeline
+      name: The Asset Pipeline
       url: asset_pipeline.html
       description: This guide documents the asset pipeline.
     -
@@ -131,11 +134,6 @@
       url: active_support_instrumentation.html
       description: This guide explains how to use the instrumentation API inside of Active Support to measure events inside of Rails and other Ruby code.
     -
-      name: Profiling Rails Applications
-      work_in_progress: true
-      url: profiling.html
-      description: This guide explains how to profile your Rails applications to improve performance.
-    -
       name: Using Rails for API-only Applications
       url: api_app.html
       description: This guide explains how to effectively use Rails to develop a JSON API application.
@@ -157,7 +155,7 @@
       url: rails_on_rack.html
       description: This guide covers Rails integration with Rack and interfacing with other Rack components.
     -
-      name: Creating and Customizing Rails Generators
+      name: Creating and Customizing Rails Generators & Templates
       url: generators.html
       description: This guide covers the process of adding a brand new generator to your extension or providing an alternative to an element of a built-in Rails generator (such as providing alternative test stubs for the scaffold generator).
     -
@@ -165,6 +163,11 @@
       url: engines.html
       description: This guide explains how to write a mountable engine.
       work_in_progress: true
+    -
+      name: Threading and Code Execution in Rails
+      url: threading_and_code_execution.html
+      description: This guide describes the considerations needed and tools available when working directly with concurrency in a Rails application.
+      work_in_progress: true
 -
   name: Contributing to Ruby on Rails
   documents:
@@ -184,7 +187,7 @@
   name: Maintenance Policy
   documents:
     -
-      name: Maintenance Policy
+      name: Maintenance Policy for Ruby on Rails
       url: maintenance_policy.html
       description: What versions of Ruby on Rails are currently supported, and when to expect new versions.
 -
@@ -195,10 +198,17 @@
       url: upgrading_ruby_on_rails.html
       description: This guide helps in upgrading applications to latest Ruby on Rails versions.
     -
+      name: Ruby on Rails 5.2 Release Notes
+      url: 5_2_release_notes.html
+      description: Release notes for Rails 5.2.
+    -
+      name: Ruby on Rails 5.1 Release Notes
+      url: 5_1_release_notes.html
+      description: Release notes for Rails 5.1.
+    -
       name: Ruby on Rails 5.0 Release Notes
       url: 5_0_release_notes.html
       description: Release notes for Rails 5.0.
-      work_in_progress: true
     -
       name: Ruby on Rails 4.2 Release Notes
       url: 4_2_release_notes.html
diff --git a/guides/source/engines.md b/guides/source/engines.md
index f9a37e45ac..8d81296fa5 100644
--- a/guides/source/engines.md
+++ b/guides/source/engines.md
@@ -14,6 +14,7 @@ After reading this guide, you will know:
 * How to build features for the engine.
 * How to hook the engine into an application.
 * How to override engine functionality in the application.
+* Avoid loading Rails frameworks with Load and Configuration Hooks
 
 --------------------------------------------------------------------------------
 
@@ -46,7 +47,7 @@ see how to hook it into an application.
 
 Engines can also be isolated from their host applications. This means that an
 application is able to have a path provided by a routing helper such as
-`articles_path` and use an engine also that provides a path also called
+`articles_path` and use an engine that also provides a path also called
 `articles_path`, and the two would not clash. Along with this, controllers, models
 and table names are also namespaced. You'll see how to do this later in this
 guide.
@@ -59,10 +60,10 @@ only be enhancing it, rather than changing it drastically.
 To see demonstrations of other engines, check out
 [Devise](https://github.com/plataformatec/devise), an engine that provides
 authentication for its parent applications, or
-[Forem](https://github.com/radar/forem), an engine that provides forum
+[Thredded](https://github.com/thredded/thredded), an engine that provides forum
 functionality. There's also [Spree](https://github.com/spree/spree) which
 provides an e-commerce platform, and
-[RefineryCMS](https://github.com/refinery/refinerycms), a CMS engine.
+[Refinery CMS](https://github.com/refinery/refinerycms), a CMS engine.
 
 Finally, engines would not have been possible without the work of James Adam,
 Piotr Sarnacki, the Rails Core Team, and a number of other people. If you ever
@@ -184,7 +185,7 @@ end
 By inheriting from the `Rails::Engine` class, this gem notifies Rails that
 there's an engine at the specified path, and will correctly mount the engine
 inside the application, performing tasks such as adding the `app` directory of
-the engine to the load path for models, mailers, controllers and views.
+the engine to the load path for models, mailers, controllers, and views.
 
 The `isolate_namespace` method here deserves special notice. This call is
 responsible for isolating the controllers, models, routes and other things into
@@ -345,6 +346,9 @@ invoke    test_unit
 create      test/controllers/blorgh/articles_controller_test.rb
 invoke    helper
 create      app/helpers/blorgh/articles_helper.rb
+invoke  test_unit
+create    test/application_system_test_case.rb
+create    test/system/articles_test.rb
 invoke  assets
 invoke    js
 create      app/assets/javascripts/blorgh/articles.js
@@ -533,12 +537,12 @@ directory at `app/views/blorgh/comments` and in it a new file called
 
 ```html+erb
 <h3>New comment</h3>
-<%= form_for [@article, @article.comments.build] do |f| %>
+<%= form_with(model: [@article, @article.comments.build], local: true) do |form| %>
   <p>
-    <%= f.label :text %><br>
-    <%= f.text_area :text %>
+    <%= form.label :text %><br>
+    <%= form.text_area :text %>
   </p>
-  <%= f.submit %>
+  <%= form.submit %>
 <% end %>
 ```
 
@@ -649,7 +653,7 @@ there isn't an application handy to test this out in, generate one using the
 $ rails new unicorn
 ```
 
-Usually, specifying the engine inside the Gemfile would be done by specifying it
+Usually, specifying the engine inside the `Gemfile` would be done by specifying it
 as a normal, everyday gem.
 
 ```ruby
@@ -779,8 +783,8 @@ added above the `title` field with this code:
 
 ```html+erb
 <div class="field">
-  <%= f.label :author_name %><br>
-  <%= f.text_field :author_name %>
+  <%= form.label :author_name %><br>
+  <%= form.text_field :author_name %>
 </div>
 ```
 
@@ -917,7 +921,7 @@ engine:
 mattr_accessor :author_class
 ```
 
-This method works like its brothers, `attr_accessor` and `cattr_accessor`, but
+This method works like its siblings, `attr_accessor` and `cattr_accessor`, but
 provides a setter and getter method on the module with the specified name. To
 use it, it must be referenced using `Blorgh.author_class`.
 
@@ -978,7 +982,7 @@ Blorgh.author_class = "User"
 WARNING: It's very important here to use the `String` version of the class,
 rather than the class itself. If you were to use the class, Rails would attempt
 to load that class and then reference the related table. This could lead to
-problems if the table wasn't already existing. Therefore, a `String` should be
+problems if the table didn't already exist. Therefore, a `String` should be
 used and then converted to a class using `constantize` in the engine later on.
 
 Go ahead and try to create a new article. You will see that it works exactly in the
@@ -1318,7 +1322,7 @@ engine.
 
 Assets within an engine work in an identical way to a full application. Because
 the engine class inherits from `Rails::Engine`, the application will know to
-look up assets in the engine's 'app/assets' and 'lib/assets' directories.
+look up assets in the engine's `app/assets` and `lib/assets` directories.
 
 Like all of the other components of an engine, the assets should be namespaced.
 This means that if you have an asset called `style.css`, it should be placed at
@@ -1357,14 +1361,14 @@ that only exists for your engine. In this case, the host application doesn't
 need to require `admin.css` or `admin.js`. Only the gem's admin layout needs
 these assets. It doesn't make sense for the host app to include
 `"blorgh/admin.css"` in its stylesheets. In this situation, you should
-explicitly define these assets for precompilation.  This tells sprockets to add
+explicitly define these assets for precompilation.  This tells Sprockets to add
 your engine assets when `bin/rails assets:precompile` is triggered.
 
 You can define assets for precompilation in `engine.rb`:
 
 ```ruby
 initializer "blorgh.assets.precompile" do |app|
-  app.config.assets.precompile += %w(admin.css admin.js)
+  app.config.assets.precompile += %w( admin.js admin.css )
 end
 ```
 
@@ -1410,3 +1414,115 @@ module MyEngine
   end
 end
 ```
+
+Active Support On Load Hooks
+----------------------------
+
+Active Support is the Ruby on Rails component responsible for providing Ruby language extensions, utilities, and other transversal utilities.
+
+Rails code can often be referenced on load of an application. Rails is responsible for the load order of these frameworks, so when you load frameworks, such as `ActiveRecord::Base`, prematurely you are violating an implicit contract your application has with Rails. Moreover, by loading code such as `ActiveRecord::Base` on boot of your application you are loading entire frameworks which may slow down your boot time and could cause conflicts with load order and boot of your application.
+
+On Load hooks are the API that allow you to hook into this initialization process without violating the load contract with Rails. This will also mitigate boot performance degradation and avoid conflicts.
+
+## What are `on_load` hooks?
+
+Since Ruby is a dynamic language, some code will cause different Rails frameworks to load. Take this snippet for instance:
+
+```ruby
+ActiveRecord::Base.include(MyActiveRecordHelper)
+```
+
+This snippet means that when this file is loaded, it will encounter `ActiveRecord::Base`. This encounter causes Ruby to look for the definition of that constant and will require it. This causes the entire Active Record framework to be loaded on boot.
+
+`ActiveSupport.on_load` is a mechanism that can be used to defer the loading of code until it is actually needed. The snippet above can be changed to:
+
+```ruby
+ActiveSupport.on_load(:active_record) { include MyActiveRecordHelper }
+```
+
+This new snippet will only include `MyActiveRecordHelper` when `ActiveRecord::Base` is loaded.
+
+## How does it work?
+
+In the Rails framework these hooks are called when a specific library is loaded. For example, when `ActionController::Base` is loaded, the `:action_controller_base` hook is called. This means that all `ActiveSupport.on_load` calls with `:action_controller_base` hooks will be called in the context of `ActionController::Base` (that means `self` will be an `ActionController::Base`).
+
+## Modifying code to use `on_load` hooks
+
+Modifying code is generally straightforward. If you have a line of code that refers to a Rails framework such as `ActiveRecord::Base` you can wrap that code in an `on_load` hook.
+
+### Example 1
+
+```ruby
+ActiveRecord::Base.include(MyActiveRecordHelper)
+```
+
+becomes
+
+```ruby
+ActiveSupport.on_load(:active_record) { include MyActiveRecordHelper } # self refers to ActiveRecord::Base here, so we can simply #include
+```
+
+### Example 2
+
+```ruby
+ActionController::Base.prepend(MyActionControllerHelper)
+```
+
+becomes
+
+```ruby
+ActiveSupport.on_load(:action_controller_base) { prepend MyActionControllerHelper } # self refers to ActionController::Base here, so we can simply #prepend
+```
+
+### Example 3
+
+```ruby
+ActiveRecord::Base.include_root_in_json = true
+```
+
+becomes
+
+```ruby
+ActiveSupport.on_load(:active_record) { self.include_root_in_json = true } # self refers to ActiveRecord::Base here
+```
+
+## Available Hooks
+
+These are the hooks you can use in your own code.
+
+To hook into the initialization process of one of the following classes use the available hook.
+
+| Class                             | Available Hooks                      |
+| --------------------------------- | ------------------------------------ |
+| `ActionCable`                     | `action_cable`                       |
+| `ActionController::API`           | `action_controller_api`              |
+| `ActionController::API`           | `action_controller`                  |
+| `ActionController::Base`          | `action_controller_base`             |
+| `ActionController::Base`          | `action_controller`                  |
+| `ActionController::TestCase`      | `action_controller_test_case`        |
+| `ActionDispatch::IntegrationTest` | `action_dispatch_integration_test`   |
+| `ActionDispatch::SystemTestCase`  | `action_dispatch_system_test_case`   |
+| `ActionMailer::Base`              | `action_mailer`                      |
+| `ActionMailer::TestCase`          | `action_mailer_test_case`            |
+| `ActionView::Base`                | `action_view`                        |
+| `ActionView::TestCase`            | `action_view_test_case`              |
+| `ActiveJob::Base`                 | `active_job`                         |
+| `ActiveJob::TestCase`             | `active_job_test_case`               |
+| `ActiveRecord::Base`              | `active_record`                      |
+| `ActiveSupport::TestCase`         | `active_support_test_case`           |
+| `i18n`                            | `i18n`                               |
+
+## Configuration hooks
+
+These are the available configuration hooks. They do not hook into any particular framework, but instead they run in context of the entire application.
+
+| Hook                   | Use Case                                                                           |
+| ---------------------- | ---------------------------------------------------------------------------------- |
+| `before_configuration` | First configurable block to run. Called before any initializers are run.           |
+| `before_initialize`    | Second configurable block to run. Called before frameworks initialize.             |
+| `before_eager_load`    | Third configurable block to run. Does not run if `config.eager_load` set to false. |
+| `after_initialize`     | Last configurable block to run. Called after frameworks initialize.                |
+
+### Example
+
+`config.before_configuration { puts 'I am called before any initializers' }`
diff --git a/guides/source/form_helpers.md b/guides/source/form_helpers.md
index 048fe190e8..53c567727f 100644
--- a/guides/source/form_helpers.md
+++ b/guides/source/form_helpers.md
@@ -1,7 +1,7 @@
 **DO NOT READ THIS FILE ON GITHUB, GUIDES ARE PUBLISHED ON http://guides.rubyonrails.org.**
 
-Form Helpers
-============
+Action View Form Helpers
+========================
 
 Forms in web applications are an essential interface for user input. However, form markup can quickly become tedious to write and maintain because of the need to handle form control naming and its numerous attributes. Rails does away with this complexity by providing view helpers for generating form markup. However, since these helpers have different use cases, developers need to know the differences between the helper methods before putting them to use.
 
@@ -164,7 +164,7 @@ make it easier for users to click the inputs.
 
 Other form controls worth mentioning are textareas, password fields,
 hidden fields, search fields, telephone fields, date fields, time fields,
-color fields, datetime fields, datetime-local fields, month fields, week fields,
+color fields, datetime-local fields, month fields, week fields,
 URL fields, email fields, number fields and range fields:
 
 ```erb
@@ -274,10 +274,12 @@ There are a few things to note here:
 The resulting HTML is:
 
 ```html
-<form accept-charset="UTF-8" action="/articles" method="post" class="nifty_form">
-  <input id="article_title" name="article[title]" type="text" />
-  <textarea id="article_body" name="article[body]" cols="60" rows="12"></textarea>
-  <input name="commit" type="submit" value="Create" />
+<form class="nifty_form" id="new_article" action="/articles" accept-charset="UTF-8" method="post">
+  <input name="utf8" type="hidden" value="&#x2713;" />
+  <input type="hidden" name="authenticity_token" value="NRkFyRWxdYNfUg7vYxLOp2SLf93lvnl+QwDWorR42Dp6yZXPhHEb6arhDOIWcqGit8jfnrPwL781/xlrzj63TA==" />
+  <input type="text" name="article[title]" id="article_title" />
+  <textarea name="article[body]" id="article_body" cols="60" rows="12"></textarea>
+  <input type="submit" name="commit" value="Create" data-disable-with="Create" />
 </form>
 ```
 
@@ -299,9 +301,11 @@ You can create a similar binding without actually creating `<form>` tags with th
 which produces the following output:
 
 ```html
-<form accept-charset="UTF-8" action="/people" class="new_person" id="new_person" method="post">
-  <input id="person_name" name="person[name]" type="text" />
-  <input id="contact_detail_phone_number" name="contact_detail[phone_number]" type="text" />
+<form class="new_person" id="new_person" action="/people" accept-charset="UTF-8" method="post">
+  <input name="utf8" type="hidden" value="&#x2713;" />
+  <input type="hidden" name="authenticity_token" value="bL13x72pldyDD8bgtkjKQakJCpd4A8JdXGbfksxBDHdf1uC0kCMqe2tvVdUYfidJt0fj3ihC4NxiVHv8GVYxJA==" />
+  <input type="text" name="person[name]" id="person_name" />
+  <input type="text" name="contact_detail[phone_number]" id="contact_detail_phone_number" />
 </form>
 ```
 
@@ -438,8 +442,6 @@ output:
 
 Whenever Rails sees that the internal value of an option being generated matches this value, it will add the `selected` attribute to that option.
 
-TIP: The second argument to `options_for_select` must be exactly equal to the desired internal value. In particular if the value is the integer `2` you cannot pass `"2"` to `options_for_select` - you must pass `2`. Be aware of values extracted from the `params` hash as they are all strings.
-
 WARNING: When `:include_blank` or `:prompt` are not present, `:include_blank` is forced true if the select attribute `required` is true, display `size` is one and `multiple` is not true.
 
 You can add arbitrary attributes to the options using hashes:
@@ -533,7 +535,7 @@ To leverage time zone support in Rails, you have to ask your users what time zon
 <%= time_zone_select(:person, :time_zone) %>
 ```
 
-There is also `time_zone_options_for_select` helper for a more manual (therefore more customizable) way of doing this. Read the API documentation to learn about the possible arguments for these two methods.
+There is also `time_zone_options_for_select` helper for a more manual (therefore more customizable) way of doing this. Read the [API documentation](http://api.rubyonrails.org/classes/ActionView/Helpers/FormOptionsHelper.html#method-i-time_zone_options_for_select) to learn about the possible arguments for these two methods.
 
 Rails _used_ to have a `country_select` helper for choosing countries, but this has been extracted to the [country_select plugin](https://github.com/stefanpenner/country_select). When using this, be aware that the exclusion or inclusion of certain names from the list can be somewhat controversial (and was the reason this functionality was extracted from Rails).
 
@@ -879,7 +881,7 @@ Active Record provides model level support via the `accepts_nested_attributes_fo
 
 ```ruby
 class Person < ApplicationRecord
-  has_many :addresses
+  has_many :addresses, inverse_of: :person
   accepts_nested_attributes_for :addresses
 end
 
@@ -918,7 +920,7 @@ When an association accepts nested attributes `fields_for` renders its block onc
 ```ruby
 def new
   @person = Person.new
-  2.times { @person.addresses.build}
+  2.times { @person.addresses.build }
 end
 ```
 
diff --git a/guides/source/generators.md b/guides/source/generators.md
index 32bbdc554a..b7b8262e4a 100644
--- a/guides/source/generators.md
+++ b/guides/source/generators.md
@@ -90,13 +90,15 @@ $ bin/rails generate generator initializer
       create  lib/generators/initializer/initializer_generator.rb
       create  lib/generators/initializer/USAGE
       create  lib/generators/initializer/templates
+      invoke  test_unit
+      create    test/lib/generators/initializer_generator_test.rb
 ```
 
 This is the generator just created:
 
 ```ruby
 class InitializerGenerator < Rails::Generators::NamedBase
-  source_root File.expand_path("../templates", __FILE__)
+  source_root File.expand_path('templates', __dir__)
 end
 ```
 
@@ -122,7 +124,7 @@ And now let's change the generator to copy this template when invoked:
 
 ```ruby
 class InitializerGenerator < Rails::Generators::NamedBase
-  source_root File.expand_path("../templates", __FILE__)
+  source_root File.expand_path('templates', __dir__)
 
   def copy_initializer_file
     copy_file "initializer.rb", "config/initializers/#{file_name}.rb"
@@ -197,6 +199,9 @@ $ bin/rails generate scaffold User name:string
       invoke    jbuilder
       create      app/views/users/index.json.jbuilder
       create      app/views/users/show.json.jbuilder
+      invoke  test_unit
+      create    test/application_system_test_case.rb
+      create    test/system/users_test.rb
       invoke  assets
       invoke    coffee
       create      app/assets/javascripts/users.coffee
@@ -208,7 +213,15 @@ $ bin/rails generate scaffold User name:string
 
 Looking at this output, it's easy to understand how generators work in Rails 3.0 and above. The scaffold generator doesn't actually generate anything, it just invokes others to do the work. This allows us to add/replace/remove any of those invocations. For instance, the scaffold generator invokes the scaffold_controller generator, which invokes erb, test_unit and helper generators. Since each generator has a single responsibility, they are easy to reuse, avoiding code duplication.
 
-Our first customization on the workflow will be to stop generating stylesheet, JavaScript and test fixture files for scaffolds. We can achieve that by changing our configuration to the following:
+If we want to avoid generating the default `app/assets/stylesheets/scaffolds.scss` file when scaffolding a new resource we can disable `scaffold_stylesheet`:
+
+```ruby
+  config.generators do |g|
+    g.scaffold_stylesheet false
+  end
+```
+
+The next customization on the workflow will be to stop generating stylesheet, JavaScript and test fixture files for scaffolds altogether. We can achieve that by changing our configuration to the following:
 
 ```ruby
 config.generators do |g|
@@ -230,6 +243,8 @@ $ bin/rails generate generator rails/my_helper
       create  lib/generators/rails/my_helper/my_helper_generator.rb
       create  lib/generators/rails/my_helper/USAGE
       create  lib/generators/rails/my_helper/templates
+      invoke  test_unit
+      create    test/lib/generators/rails/my_helper_generator_test.rb
 ```
 
 After that, we can delete both the `templates` directory and the `source_root`
@@ -407,6 +422,9 @@ $ bin/rails generate scaffold Comment body:text
       invoke    jbuilder
       create      app/views/comments/index.json.jbuilder
       create      app/views/comments/show.json.jbuilder
+      invoke  test_unit
+      create    test/application_system_test_case.rb
+      create    test/system/comments_test.rb
       invoke  assets
       invoke    coffee
       create      app/assets/javascripts/comments.coffee
@@ -418,7 +436,7 @@ Fallbacks allow your generators to have a single responsibility, increasing code
 Application Templates
 ---------------------
 
-Now that you've seen how generators can be used _inside_ an application, did you know they can also be used to _generate_ applications too? This kind of generator is referred as a "template". This is a brief overview of the Templates API. For detailed documentation see the [Rails Application Templates guide](rails_application_templates.html).
+Now that you've seen how generators can be used _inside_ an application, did you know they can also be used to _generate_ applications too? This kind of generator is referred to as a "template". This is a brief overview of the Templates API. For detailed documentation see the [Rails Application Templates guide](rails_application_templates.html).
 
 ```ruby
 gem "rspec-rails", group: "test"
@@ -451,6 +469,26 @@ $ rails new thud -m https://gist.github.com/radar/722911/raw/
 
 Whilst the final section of this guide doesn't cover how to generate the most awesome template known to man, it will take you through the methods available at your disposal so that you can develop it yourself. These same methods are also available for generators.
 
+Adding Command Line Arguments
+-----------------------------
+Rails generators can be easily modified to accept custom command line arguments. This functionality comes from [Thor](http://www.rubydoc.info/github/erikhuda/thor/master/Thor/Base/ClassMethods#class_option-instance_method):
+
+```
+class_option :scope, type: :string, default: 'read_products'
+```
+
+Now our generator can be invoked as follows:
+
+```bash
+rails generate initializer --scope write_products
+```
+
+The command line arguments are accessed through the `options` method inside the generator class. e.g:
+
+```ruby
+@scope = options['scope']
+```
+
 Generator methods
 -----------------
 
@@ -476,13 +514,13 @@ Available options are:
 Any additional options passed to this method are put on the end of the line:
 
 ```ruby
-gem "devise", git: "git://github.com/plataformatec/devise", branch: "master"
+gem "devise", git: "https://github.com/plataformatec/devise.git", branch: "master"
 ```
 
 The above code will put the following line into `Gemfile`:
 
 ```ruby
-gem "devise", git: "git://github.com/plataformatec/devise", branch: "master"
+gem "devise", git: "https://github.com/plataformatec/devise.git", branch: "master"
 ```
 
 ### `gem_group`
@@ -599,7 +637,7 @@ This method also takes a block:
 
 ```ruby
 lib "super_special.rb" do
-  puts "Super special!"
+  "puts 'Super special!'"
 end
 ```
 
@@ -608,7 +646,7 @@ end
 Creates a Rake file in the `lib/tasks` directory of the application.
 
 ```ruby
-rakefile "test.rake", "hello there"
+rakefile "test.rake", 'task(:hello) { puts "Hello, there" }'
 ```
 
 This method also takes a block:
@@ -661,14 +699,6 @@ Available options are:
 * `:env` - Specifies the environment in which to run this rake task.
 * `:sudo` - Whether or not to run this task using `sudo`. Defaults to `false`.
 
-### `capify!`
-
-Runs the `capify` command from Capistrano at the root of the application which generates Capistrano configuration.
-
-```ruby
-capify!
-```
-
 ### `route`
 
 Adds text to the `config/routes.rb` file:
diff --git a/guides/source/getting_started.md b/guides/source/getting_started.md
index 65fdd7ca0d..b007baea87 100644
--- a/guides/source/getting_started.md
+++ b/guides/source/getting_started.md
@@ -20,16 +20,7 @@ Guide Assumptions
 
 This guide is designed for beginners who want to get started with a Rails
 application from scratch. It does not assume that you have any prior experience
-with Rails. However, to get the most out of it, you need to have some
-prerequisites installed:
-
-* The [Ruby](https://www.ruby-lang.org/en/downloads) language version 2.2.2 or newer.
-* Right version of [Development Kit](http://rubyinstaller.org/downloads/), if you
-  are using Windows.
-* The [RubyGems](https://rubygems.org) packaging system, which is installed with
-  Ruby by default. To learn more about RubyGems, please read the
-  [RubyGems Guides](http://guides.rubygems.org).
-* A working installation of the [SQLite3 Database](https://www.sqlite.org).
+with Rails.
 
 Rails is a web application framework running on the Ruby programming language.
 If you have no prior experience with Ruby, you will find a very steep learning
@@ -46,7 +37,7 @@ development with Rails.
 What is Rails?
 --------------
 
-Rails is a web application development framework written in the Ruby language.
+Rails is a web application development framework written in the Ruby programming language.
 It is designed to make programming web applications easier by making assumptions
 about what every developer needs to get started. It allows you to write less
 code while accomplishing more than many other languages and frameworks.
@@ -68,7 +59,7 @@ The Rails philosophy includes two major guiding principles:
   again, our code is more maintainable, more extensible, and less buggy.
 * **Convention Over Configuration:** Rails has opinions about the best way to do many
   things in a web application, and defaults to this set of conventions, rather than
-  require that you specify every minutiae through endless configuration files.
+  require that you specify minutiae through endless configuration files.
 
 Creating a New Rails Project
 ----------------------------
@@ -86,7 +77,10 @@ your prompt will look something like `c:\source_code>`
 
 ### Installing Rails
 
-Open up a command line prompt. On Mac OS X open Terminal.app, on Windows choose
+Before you install Rails, you should check to make sure that your system has the
+proper prerequisites installed. These include Ruby and SQLite3.
+
+Open up a command line prompt. On macOS open Terminal.app, on Windows choose
 "Run" from your Start menu and type 'cmd.exe'. Any commands prefaced with a
 dollar sign `$` should be run in the command line. Verify that you have a
 current version of Ruby installed:
@@ -96,12 +90,19 @@ $ ruby -v
 ruby 2.3.1p112
 ```
 
+Rails requires Ruby version 2.2.2 or later. If the version number returned is
+less than that number, you'll need to install a fresh copy of Ruby.
+
 TIP: A number of tools exist to help you quickly install Ruby and Ruby
 on Rails on your system. Windows users can use [Rails Installer](http://railsinstaller.org),
-while Mac OS X users can use [Tokaido](https://github.com/tokaido/tokaidoapp).
+while macOS users can use [Tokaido](https://github.com/tokaido/tokaidoapp).
 For more installation methods for most Operating Systems take a look at
 [ruby-lang.org](https://www.ruby-lang.org/en/documentation/installation/).
 
+If you are working on Windows, you should also install the
+[Ruby Installer Development Kit](http://rubyinstaller.org/downloads/).
+
+You will also need an installation of the SQLite3 database.
 Many popular UNIX-like OSes ship with an acceptable version of SQLite3.
 On Windows, if you installed Rails through Rails Installer, you
 already have SQLite installed. Others can find installation instructions
@@ -127,7 +128,7 @@ run the following:
 $ rails --version
 ```
 
-If it says something like "Rails 5.0.0", you are ready to continue.
+If it says something like "Rails 5.1.1", you are ready to continue.
 
 ### Creating the Blog Application
 
@@ -148,6 +149,10 @@ This will create a Rails application called Blog in a `blog` directory and
 install the gem dependencies that are already mentioned in `Gemfile` using
 `bundle install`.
 
+NOTE: If you're using Windows Subsystem for Linux then there are currently some
+limitations on file system notifications that mean you should disable the `spring`
+and `listen` gems which you can do by running `rails new blog --skip-spring --skip-listen`.
+
 TIP: You can see all of the command line options that the Rails application
 builder accepts by running `rails new -h`.
 
@@ -167,17 +172,20 @@ of the files and folders that Rails created by default:
 |app/|Contains the controllers, models, views, helpers, mailers, channels, jobs and assets for your application. You'll focus on this folder for the remainder of this guide.|
 |bin/|Contains the rails script that starts your app and can contain other scripts you use to setup, update, deploy or run your application.|
 |config/|Configure your application's routes, database, and more. This is covered in more detail in [Configuring Rails Applications](configuring.html).|
-|config.ru|Rack configuration for Rack based servers used to start the application.|
+|config.ru|Rack configuration for Rack based servers used to start the application. For more information about Rack, see the [Rack website](https://rack.github.io/).|
 |db/|Contains your current database schema, as well as the database migrations.|
-|Gemfile<br>Gemfile.lock|These files allow you to specify what gem dependencies are needed for your Rails application. These files are used by the Bundler gem. For more information about Bundler, see the [Bundler website](http://bundler.io).|
+|Gemfile<br>Gemfile.lock|These files allow you to specify what gem dependencies are needed for your Rails application. These files are used by the Bundler gem. For more information about Bundler, see the [Bundler website](https://bundler.io).|
 |lib/|Extended modules for your application.|
 |log/|Application log files.|
+|package.json|This file allows you to specify what npm dependencies are needed for your Rails application. This file is used by Yarn. For more information about Yarn, see the [Yarn website](https://yarnpkg.com/lang/en/).|
 |public/|The only folder seen by the world as-is. Contains static files and compiled assets.|
-|Rakefile|This file locates and loads tasks that can be run from the command line. The task definitions are defined throughout the components of Rails. Rather than changing Rakefile, you should add your own tasks by adding files to the lib/tasks directory of your application.|
+|Rakefile|This file locates and loads tasks that can be run from the command line. The task definitions are defined throughout the components of Rails. Rather than changing `Rakefile`, you should add your own tasks by adding files to the `lib/tasks` directory of your application.|
 |README.md|This is a brief instruction manual for your application. You should edit this file to tell others what your application does, how to set it up, and so on.|
 |test/|Unit tests, fixtures, and other test apparatus. These are covered in [Testing Rails Applications](testing.html).|
 |tmp/|Temporary files (like cache and pid files).|
 |vendor/|A place for all third-party code. In a typical Rails application this includes vendored gems.|
+|.gitignore|This file tells git which files (or patterns) it should ignore. See [GitHub - Ignoring files](https://help.github.com/articles/ignoring-files) for more info about ignoring files.
+|.ruby-version|This file contains the default Ruby version.|
 
 Hello, Rails!
 -------------
@@ -201,8 +209,8 @@ folder directly to the Ruby interpreter e.g. `ruby bin\rails server`.
 TIP: Compiling CoffeeScript and JavaScript asset compression requires you
 have a JavaScript runtime available on your system, in the absence
 of a runtime you will see an `execjs` error during asset compilation.
-Usually Mac OS X and Windows come with a JavaScript runtime installed.
-Rails adds the `therubyracer` gem to the generated `Gemfile` in a
+Usually macOS and Windows come with a JavaScript runtime installed.
+Rails adds the `mini_racer` gem to the generated `Gemfile` in a
 commented line for new apps and you can uncomment if you need it.
 `therubyrhino` is the recommended runtime for JRuby users and is added by
 default to the `Gemfile` in apps generated under JRuby. You can investigate
@@ -216,7 +224,7 @@ your application in action, open a browser window and navigate to
 
 TIP: To stop the web server, hit Ctrl+C in the terminal window where it's
 running. To verify the server has stopped you should see your command prompt
-cursor again. For most UNIX-like systems including Mac OS X this will be a
+cursor again. For most UNIX-like systems including macOS this will be a
 dollar sign `$`. In development mode, Rails does not generally require you to
 restart the server; changes you make in files will be automatically picked up by
 the server.
@@ -299,14 +307,11 @@ Rails.application.routes.draw do
   get 'welcome/index'
 
   # For details on the DSL available within this file, see http://guides.rubyonrails.org/routing.html
-
-  # Serve websocket cable requests in-process
-  # mount ActionCable.server => '/cable'
 end
 ```
 
 This is your application's _routing file_ which holds entries in a special
-[DSL (domain-specific language)](http://en.wikipedia.org/wiki/Domain-specific_language)
+[DSL (domain-specific language)](https://en.wikipedia.org/wiki/Domain-specific_language)
 that tells Rails how to connect incoming requests to
 controllers and actions.
 Edit this file by adding the line of code `root 'welcome#index'`.
@@ -316,10 +321,6 @@ It should look something like the following:
 Rails.application.routes.draw do
   get 'welcome/index'
 
-  # For details on the DSL available within this file, see http://guides.rubyonrails.org/routing.html
-
-  # Serve websocket cable requests in-process
-  # mount ActionCable.server => '/cable'
   root 'welcome#index'
 end
 ```
@@ -356,6 +357,7 @@ resource. You need to add the _article resource_ to the
 
 ```ruby
 Rails.application.routes.draw do
+  get 'welcome/index'
 
   resources :articles
 
@@ -370,16 +372,17 @@ singular form `article` and makes meaningful use of the distinction.
 
 ```bash
 $ bin/rails routes
-      Prefix Verb   URI Pattern                  Controller#Action
-    articles GET    /articles(.:format)          articles#index
-             POST   /articles(.:format)          articles#create
- new_article GET    /articles/new(.:format)      articles#new
-edit_article GET    /articles/:id/edit(.:format) articles#edit
-     article GET    /articles/:id(.:format)      articles#show
-             PATCH  /articles/:id(.:format)      articles#update
-             PUT    /articles/:id(.:format)      articles#update
-             DELETE /articles/:id(.:format)      articles#destroy
-        root GET    /                            welcome#index
+       Prefix Verb   URI Pattern                  Controller#Action
+welcome_index GET    /welcome/index(.:format)     welcome#index
+     articles GET    /articles(.:format)          articles#index
+              POST   /articles(.:format)          articles#create
+  new_article GET    /articles/new(.:format)      articles#new
+ edit_article GET    /articles/:id/edit(.:format) articles#edit
+      article GET    /articles/:id(.:format)      articles#show
+              PATCH  /articles/:id(.:format)      articles#update
+              PUT    /articles/:id(.:format)      articles#update
+              DELETE /articles/:id(.:format)      articles#destroy
+         root GET    /                            welcome#index
 ```
 
 In the next section, you will add the ability to create new articles in your
@@ -462,7 +465,7 @@ available, Rails will raise an exception.
 In the above image, the bottom line has been truncated. Let's see what the full
 error message looks like:
 
->Missing template articles/new, application/new with {locale:[:en], formats:[:html], handlers:[:erb, :builder, :coffee]}. Searched in: * "/path/to/blog/app/views"
+>ArticlesController#new is missing a template for this request format and variant. request.formats: ["text/html"] request.variant: [] NOTE! For XHR/Ajax or API requests, this action would normally respond with 204 No Content: an empty white screen. Since you're loading it in a web browser, we assume that you expected to actually render a template, not… nothing, so we're showing an error to be extra-clear. If you expect 204 No Content, carry on. That's what you'll get from an XHR or API request. Give it a shot.
 
 That's quite a lot of text! Let's quickly go through and understand what each
 part of it means.
@@ -472,27 +475,24 @@ The first part identifies which template is missing. In this case, it's the
 then it will attempt to load a template called `application/new`. It looks for
 one here because the `ArticlesController` inherits from `ApplicationController`.
 
-The next part of the message contains a hash. The `:locale` key in this hash
-simply indicates which spoken language template should be retrieved. By default,
-this is the English - or "en" - template. The next key, `:formats` specifies the
-format of the template to be served in response. The default format is `:html`, and
-so Rails is looking for an HTML template. The final key, `:handlers`, is telling
-us what _template handlers_ could be used to render our template. `:erb` is most
-commonly used for HTML templates, `:builder` is used for XML templates, and
-`:coffee` uses CoffeeScript to build JavaScript templates.
-
-The final part of this message tells us where Rails has looked for the templates.
-Templates within a basic Rails application like this are kept in a single
-location, but in more complex applications it could be many different paths.
+The next part of the message contains `request.formats` which specifies
+the format of template to be served in response. It is set to `text/html` as we
+requested this page via browser, so Rails is looking for an HTML template.
+`request.variant` specifies what kind of physical devices would be served by
+the response and helps Rails determine which template to use in the response.
+It is empty because no information has been provided.
 
 The simplest template that would work in this case would be one located at
 `app/views/articles/new.html.erb`. The extension of this file name is important:
 the first extension is the _format_ of the template, and the second extension
-is the _handler_ that will be used. Rails is attempting to find a template
-called `articles/new` within `app/views` for the application. The format for
-this template can only be `html` and the handler must be one of `erb`,
-`builder` or `coffee`. Because you want to create a new HTML form, you will be
-using the `ERB` language which is designed to embed Ruby in HTML.
+is the _handler_ that will be used to render the template. Rails is attempting
+to find a template called `articles/new` within `app/views` for the
+application. The format for this template can only be `html` and the default
+handler for HTML is `erb`. Rails uses other handlers for other formats.
+`builder` handler is used to build XML templates and `coffee` handler uses
+CoffeeScript to build JavaScript templates. Since you want to create a new
+HTML form, you will be using the `ERB` language which is designed to embed Ruby
+in HTML.
 
 Therefore the file should be called `articles/new.html.erb` and needs to be
 located inside the `app/views` directory of the application.
@@ -512,36 +512,36 @@ harmoniously! It's time to create the form for a new article.
 
 To create a form within this template, you will use a *form
 builder*. The primary form builder for Rails is provided by a helper
-method called `form_for`. To use this method, add this code into
+method called `form_with`. To use this method, add this code into
 `app/views/articles/new.html.erb`:
 
 ```html+erb
-<%= form_for :article do |f| %>
+<%= form_with scope: :article, local: true do |form| %>
   <p>
-    <%= f.label :title %><br>
-    <%= f.text_field :title %>
+    <%= form.label :title %><br>
+    <%= form.text_field :title %>
   </p>
 
   <p>
-    <%= f.label :text %><br>
-    <%= f.text_area :text %>
+    <%= form.label :text %><br>
+    <%= form.text_area :text %>
   </p>
 
   <p>
-    <%= f.submit %>
+    <%= form.submit %>
   </p>
 <% end %>
 ```
 
-If you refresh the page now, you'll see the exact same form as in the example.
+If you refresh the page now, you'll see the exact same form from our example above.
 Building forms in Rails is really just that easy!
 
-When you call `form_for`, you pass it an identifying object for this
-form. In this case, it's the symbol `:article`. This tells the `form_for`
+When you call `form_with`, you pass it an identifying scope for this
+form. In this case, it's the symbol `:article`. This tells the `form_with`
 helper what this form is for. Inside the block for this method, the
-`FormBuilder` object - represented by `f` - is used to build two labels and two
+`FormBuilder` object - represented by `form` - is used to build two labels and two
 text fields, one each for the title and text of an article. Finally, a call to
-`submit` on the `f` object will create a submit button for the form.
+`submit` on the `form` object will create a submit button for the form.
 
 There's one problem with this form though. If you inspect the HTML that is
 generated, by viewing the source of the page, you will see that the `action`
@@ -550,15 +550,15 @@ this route goes to the very page that you're on right at the moment, and that
 route should only be used to display the form for a new article.
 
 The form needs to use a different URL in order to go somewhere else.
-This can be done quite simply with the `:url` option of `form_for`.
+This can be done quite simply with the `:url` option of `form_with`.
 Typically in Rails, the action that is used for new form submissions
 like this is called "create", and so the form should be pointed to that action.
 
-Edit the `form_for` line inside `app/views/articles/new.html.erb` to look like
+Edit the `form_with` line inside `app/views/articles/new.html.erb` to look like
 this:
 
 ```html+erb
-<%= form_for :article, url: articles_path do |f| %>
+<%= form_with scope: :article, url: articles_path, local: true do |form| %>
 ```
 
 In this example, the `articles_path` helper is passed to the `:url` option.
@@ -568,15 +568,16 @@ To see what Rails will do with this, we look back at the output of
 ```bash
 $ bin/rails routes
       Prefix Verb   URI Pattern                  Controller#Action
-    articles GET    /articles(.:format)          articles#index
-             POST   /articles(.:format)          articles#create
- new_article GET    /articles/new(.:format)      articles#new
-edit_article GET    /articles/:id/edit(.:format) articles#edit
-     article GET    /articles/:id(.:format)      articles#show
-             PATCH  /articles/:id(.:format)      articles#update
-             PUT    /articles/:id(.:format)      articles#update
-             DELETE /articles/:id(.:format)      articles#destroy
-        root GET    /                            welcome#index
+welcome_index GET    /welcome/index(.:format)     welcome#index
+     articles GET    /articles(.:format)          articles#index
+              POST   /articles(.:format)          articles#create
+  new_article GET    /articles/new(.:format)      articles#new
+ edit_article GET    /articles/:id/edit(.:format) articles#edit
+      article GET    /articles/:id(.:format)      articles#show
+              PATCH  /articles/:id(.:format)      articles#update
+              PUT    /articles/:id(.:format)      articles#update
+              DELETE /articles/:id(.:format)      articles#destroy
+         root GET    /                            welcome#index
 ```
 
 The `articles_path` helper tells Rails to point the form to the URI Pattern
@@ -595,6 +596,10 @@ familiar error:
 You now need to create the `create` action within the `ArticlesController` for
 this to work.
 
+NOTE: By default `form_with` submits forms using Ajax thereby skipping full page
+redirects. To make this guide easier to get into we've disabled that with
+`local: true` for now.
+
 ### Creating articles
 
 To make the "Unknown action" go away, you can define a `create` action within
@@ -611,9 +616,11 @@ class ArticlesController < ApplicationController
 end
 ```
 
-If you re-submit the form now, you'll see another familiar error: a template is
-missing. That's ok, we can ignore that for now. What the `create` action should
-be doing is saving our new article to the database.
+If you re-submit the form now, you may not see any change on the page. Don't worry!
+This is because Rails by default returns `204 No Content` response for an action if
+we don't specify what the response should be. We just added the `create` action
+but didn't specify anything about how the response should be. In this case, the
+`create` action should save our new article to the database.
 
 When a form is submitted, the fields of the form are sent to Rails as
 _parameters_. These parameters can then be referenced inside the controller
@@ -635,8 +642,7 @@ this situation, the only parameters that matter are the ones from the form.
 
 TIP: Ensure you have a firm grasp of the `params` method, as you'll use it fairly regularly. Let's consider an example URL: **http://www.example.com/?username=dhh&email=dhh@email.com**. In this URL, `params[:username]` would equal "dhh" and `params[:email]` would equal "dhh@email.com".
 
-If you re-submit the form one more time you'll now no longer get the missing
-template error. Instead, you'll see something that looks like the following:
+If you re-submit the form one more time, you'll see something that looks like the following:
 
 ```ruby
 <ActionController::Parameters {"title"=>"First Article!", "text"=>"This is my first article."} permitted: false>
@@ -703,8 +709,8 @@ in case you want to reverse it later. When you run this migration it will create
 an `articles` table with one string column and a text column. It also creates
 two timestamp fields to allow Rails to track article creation and update times.
 
-TIP: For more information about migrations, refer to [Rails Database Migrations]
-(migrations.html).
+TIP: For more information about migrations, refer to [Active Record Migrations]
+(active_record_migrations.html).
 
 At this point, you can use a bin/rails command to run the migration:
 
@@ -830,7 +836,7 @@ NOTE: A frequent practice is to place the standard CRUD actions in each
 controller in the following order: `index`, `show`, `new`, `edit`, `create`, `update`
 and `destroy`. You may use any order you choose, but keep in mind that these
 are public methods; as mentioned earlier in this guide, they must be placed
-before any private or protected method in the controller in order to work.
+before declaring `private` visibility in the controller.
 
 Given that, let's add the `show` action, as follows:
 
@@ -912,6 +918,7 @@ And then finally, add the view for this action, located at
   <tr>
     <th>Title</th>
     <th>Text</th>
+    <th></th>
   </tr>
 
   <% @articles.each do |article| %>
@@ -957,7 +964,7 @@ Now, add another link in `app/views/articles/new.html.erb`, underneath the
 form, to go back to the `index` action:
 
 ```erb
-<%= form_for :article, url: articles_path do |f| %>
+<%= form_with scope: :article, url: articles_path, local: true do |form| %>
   ...
 <% end %>
 
@@ -1068,7 +1075,7 @@ something went wrong. To do that, you'll modify
 `app/views/articles/new.html.erb` to check for error messages:
 
 ```html+erb
-<%= form_for :article, url: articles_path do |f| %>
+<%= form_with scope: :article, url: articles_path, local: true do |form| %>
 
   <% if @article.errors.any? %>
     <div id="error_explanation">
@@ -1085,17 +1092,17 @@ something went wrong. To do that, you'll modify
   <% end %>
 
   <p>
-    <%= f.label :title %><br>
-    <%= f.text_field :title %>
+    <%= form.label :title %><br>
+    <%= form.text_field :title %>
   </p>
 
   <p>
-    <%= f.label :text %><br>
-    <%= f.text_area :text %>
+    <%= form.label :text %><br>
+    <%= form.text_area :text %>
   </p>
 
   <p>
-    <%= f.submit %>
+    <%= form.submit %>
   </p>
 
 <% end %>
@@ -1158,9 +1165,9 @@ new articles. Create a file called `app/views/articles/edit.html.erb` and make
 it look as follows:
 
 ```html+erb
-<h1>Editing article</h1>
+<h1>Edit article</h1>
 
-<%= form_for :article, url: article_path(@article), method: :patch do |f| %>
+<%= form_with(model: @article, local: true) do |form| %>
 
   <% if @article.errors.any? %>
     <div id="error_explanation">
@@ -1177,17 +1184,17 @@ it look as follows:
   <% end %>
 
   <p>
-    <%= f.label :title %><br>
-    <%= f.text_field :title %>
+    <%= form.label :title %><br>
+    <%= form.text_field :title %>
   </p>
 
   <p>
-    <%= f.label :text %><br>
-    <%= f.text_area :text %>
+    <%= form.label :text %><br>
+    <%= form.text_area :text %>
   </p>
 
   <p>
-    <%= f.submit %>
+    <%= form.submit %>
   </p>
 
 <% end %>
@@ -1198,16 +1205,16 @@ it look as follows:
 This time we point the form to the `update` action, which is not defined yet
 but will be very soon.
 
-The `method: :patch` option tells Rails that we want this form to be submitted
+Passing the article object to the method, will automagically create url for submitting the edited article form.
+This option tells Rails that we want this form to be submitted
 via the `PATCH` HTTP method which is the HTTP method you're expected to use to
 **update** resources according to the REST protocol.
 
-The first parameter of `form_for` can be an object, say, `@article` which would
+The arguments to `form_with` could be model objects, say, `model: @article` which would
 cause the helper to fill in the form with the fields of the object. Passing in a
-symbol (`:article`) with the same name as the instance variable (`@article`)
-also automagically leads to the same behavior. This is what is happening here.
-More details can be found in [form_for documentation]
-(http://api.rubyonrails.org/classes/ActionView/Helpers/FormHelper.html#method-i-form_for).
+symbol scope (`scope: :article`) just creates the fields but without anything filled into them.
+More details can be found in [form_with documentation]
+(http://api.rubyonrails.org/classes/ActionView/Helpers/FormHelper.html#method-i-form_with).
 
 Next, we need to create the `update` action in
 `app/controllers/articles_controller.rb`.
@@ -1304,7 +1311,7 @@ Create a new file `app/views/articles/_form.html.erb` with the following
 content:
 
 ```html+erb
-<%= form_for @article do |f| %>
+<%= form_with model: @article, local: true do |form| %>
 
   <% if @article.errors.any? %>
     <div id="error_explanation">
@@ -1321,29 +1328,29 @@ content:
   <% end %>
 
   <p>
-    <%= f.label :title %><br>
-    <%= f.text_field :title %>
+    <%= form.label :title %><br>
+    <%= form.text_field :title %>
   </p>
 
   <p>
-    <%= f.label :text %><br>
-    <%= f.text_area :text %>
+    <%= form.label :text %><br>
+    <%= form.text_area :text %>
   </p>
 
   <p>
-    <%= f.submit %>
+    <%= form.submit %>
   </p>
 
 <% end %>
 ```
 
-Everything except for the `form_for` declaration remained the same.
-The reason we can use this shorter, simpler `form_for` declaration
+Everything except for the `form_with` declaration remained the same.
+The reason we can use this shorter, simpler `form_with` declaration
 to stand in for either of the other forms is that `@article` is a *resource*
 corresponding to a full set of RESTful routes, and Rails is able to infer
 which URI and method to use.
-For more information about this use of `form_for`, see [Resource-oriented style]
-(http://api.rubyonrails.org/classes/ActionView/Helpers/FormHelper.html#method-i-form_for-label-Resource-oriented+style).
+For more information about this use of `form_with`, see [Resource-oriented style]
+(http://api.rubyonrails.org/classes/ActionView/Helpers/FormHelper.html#method-i-form_with-label-Resource-oriented+style).
 
 Now, let's update the `app/views/articles/new.html.erb` view to use this new
 partial, rewriting it completely:
@@ -1490,14 +1497,14 @@ second argument, and then the options as another argument. The `method: :delete`
 and `data: { confirm: 'Are you sure?' }` options are used as HTML5 attributes so
 that when the link is clicked, Rails will first show a confirm dialog to the
 user, and then submit the link with method `delete`.  This is done via the
-JavaScript file `jquery_ujs` which is automatically included in your
+JavaScript file `rails-ujs` which is automatically included in your
 application's layout (`app/views/layouts/application.html.erb`) when you
 generated the application. Without this file, the confirmation dialog box won't
 appear.
 
 ![Confirm Dialog](images/getting_started/confirm_dialog.png)
 
-TIP: Learn more about jQuery Unobtrusive Adapter (jQuery UJS) on
+TIP: Learn more about Unobtrusive JavaScript on
 [Working With JavaScript in Rails](working_with_javascript_in_rails.html) guide.
 
 Congratulations, you can now create, show, list, update and destroy
@@ -1546,8 +1553,8 @@ You'll learn a little about associations in the next section of this guide.
 
 The (`:references`) keyword used in the bash command is a special data type for models.
 It creates a new column on your database table with the provided model name appended with an `_id`
-that can hold integer values. You can get a better understanding after analyzing the
-`db/schema.rb` file below.
+that can hold integer values. To get a better understanding, analyze the
+`db/schema.rb` file after running the migration.
 
 In addition to the model, Rails has also made a migration to create the
 corresponding database table:
@@ -1658,8 +1665,8 @@ This creates five files and one empty directory:
 | app/views/comments/                          | Views of the controller are stored here  |
 | test/controllers/comments_controller_test.rb | The test for the controller              |
 | app/helpers/comments_helper.rb               | A view helper file                       |
-| app/assets/javascripts/comment.coffee        | CoffeeScript for the controller          |
-| app/assets/stylesheets/comment.scss          | Cascading style sheet for the controller |
+| app/assets/javascripts/comments.coffee       | CoffeeScript for the controller          |
+| app/assets/stylesheets/comments.scss         | Cascading style sheet for the controller |
 
 Like with any blog, our readers will create their comments directly after
 reading the article, and once they have added their comment, will be sent back
@@ -1682,17 +1689,17 @@ So first, we'll wire up the Article show template
 </p>
 
 <h2>Add a comment:</h2>
-<%= form_for([@article, @article.comments.build]) do |f| %>
+<%= form_with(model: [ @article, @article.comments.build ], local: true) do |form| %>
   <p>
-    <%= f.label :commenter %><br>
-    <%= f.text_field :commenter %>
+    <%= form.label :commenter %><br>
+    <%= form.text_field :commenter %>
   </p>
   <p>
-    <%= f.label :body %><br>
-    <%= f.text_area :body %>
+    <%= form.label :body %><br>
+    <%= form.text_area :body %>
   </p>
   <p>
-    <%= f.submit %>
+    <%= form.submit %>
   </p>
 <% end %>
 
@@ -1701,7 +1708,7 @@ So first, we'll wire up the Article show template
 ```
 
 This adds a form on the `Article` show page that creates a new comment by
-calling the `CommentsController` `create` action. The `form_for` call here uses
+calling the `CommentsController` `create` action. The `form_with` call here uses
 an array, which will build a nested route, such as `/articles/1/comments`.
 
 Let's wire up the `create` in `app/controllers/comments_controller.rb`:
@@ -1763,17 +1770,17 @@ add that to the `app/views/articles/show.html.erb`.
 <% end %>
 
 <h2>Add a comment:</h2>
-<%= form_for([@article, @article.comments.build]) do |f| %>
+<%= form_with(model: [ @article, @article.comments.build ], local: true) do |form| %>
   <p>
-    <%= f.label :commenter %><br>
-    <%= f.text_field :commenter %>
+    <%= form.label :commenter %><br>
+    <%= form.text_field :commenter %>
   </p>
   <p>
-    <%= f.label :body %><br>
-    <%= f.text_area :body %>
+    <%= form.label :body %><br>
+    <%= form.text_area :body %>
   </p>
   <p>
-    <%= f.submit %>
+    <%= form.submit %>
   </p>
 <% end %>
 
@@ -1829,17 +1836,17 @@ following:
 <%= render @article.comments %>
 
 <h2>Add a comment:</h2>
-<%= form_for([@article, @article.comments.build]) do |f| %>
+<%= form_with(model: [ @article, @article.comments.build ], local: true) do |form| %>
   <p>
-    <%= f.label :commenter %><br>
-    <%= f.text_field :commenter %>
+    <%= form.label :commenter %><br>
+    <%= form.text_field :commenter %>
   </p>
   <p>
-    <%= f.label :body %><br>
-    <%= f.text_area :body %>
+    <%= form.label :body %><br>
+    <%= form.text_area :body %>
   </p>
   <p>
-    <%= f.submit %>
+    <%= form.submit %>
   </p>
 <% end %>
 
@@ -1859,17 +1866,17 @@ Let us also move that new comment section out to its own partial. Again, you
 create a file `app/views/comments/_form.html.erb` containing:
 
 ```html+erb
-<%= form_for([@article, @article.comments.build]) do |f| %>
+<%= form_with(model: [ @article, @article.comments.build ], local: true) do |form| %>
   <p>
-    <%= f.label :commenter %><br>
-    <%= f.text_field :commenter %>
+    <%= form.label :commenter %><br>
+    <%= form.text_field :commenter %>
   </p>
   <p>
-    <%= f.label :body %><br>
-    <%= f.text_area :body %>
+    <%= form.label :body %><br>
+    <%= form.text_area :body %>
   </p>
   <p>
-    <%= f.submit %>
+    <%= form.submit %>
   </p>
 <% end %>
 ```
diff --git a/guides/source/i18n.md b/guides/source/i18n.md
index f3802a142f..2b545e6b82 100644
--- a/guides/source/i18n.md
+++ b/guides/source/i18n.md
@@ -72,11 +72,13 @@ I18n.l Time.now
 There are also attribute readers and writers for the following attributes:
 
 ```ruby
-load_path         # Announce your custom translation files
-locale            # Get and set the current locale
-default_locale    # Get and set the default locale
-exception_handler # Use a different exception_handler
-backend           # Use a different backend
+load_path                 # Announce your custom translation files
+locale                    # Get and set the current locale
+default_locale            # Get and set the default locale
+available_locales         # Whitelist locales available for the application
+enforce_available_locales # Enforce locale whitelisting (true or false)
+exception_handler         # Use a different exception_handler
+backend                   # Use a different backend
 ```
 
 So, let's internationalize a simple Rails application from the ground up in the next chapters!
@@ -103,7 +105,7 @@ This means, that in the `:en` locale, the key _hello_ will map to the _Hello wor
 
 The I18n library will use **English** as a **default locale**, i.e. if a different locale is not set, `:en` will be used for looking up translations.
 
-NOTE: The i18n library takes a **pragmatic approach** to locale keys (after [some discussion](http://groups.google.com/group/rails-i18n/browse_thread/thread/14dede2c7dbe9470/80eec34395f64f3c?hl=en)), including only the _locale_ ("language") part, like `:en`, `:pl`, not the _region_ part, like `:en-US` or `:en-GB`, which are traditionally used for separating "languages" and "regional setting" or "dialects". Many international applications use only the "language" element of a locale such as `:cs`, `:th` or `:es` (for Czech, Thai and Spanish). However, there are also regional differences within different language groups that may be important. For instance, in the `:en-US` locale you would have $ as a currency symbol, while in `:en-GB`, you would have £. Nothing stops you from separating regional and other settings in this way: you just have to provide full "English - United Kingdom" locale in a `:en-GB` dictionary. Few gems such as [Globalize3](https://github.com/globalize/globalize) may help you implement it.
+NOTE: The i18n library takes a **pragmatic approach** to locale keys (after [some discussion](https://groups.google.com/forum/#!topic/rails-i18n/FN7eLH2-lHA)), including only the _locale_ ("language") part, like `:en`, `:pl`, not the _region_ part, like `:en-US` or `:en-GB`, which are traditionally used for separating "languages" and "regional setting" or "dialects". Many international applications use only the "language" element of a locale such as `:cs`, `:th` or `:es` (for Czech, Thai and Spanish). However, there are also regional differences within different language groups that may be important. For instance, in the `:en-US` locale you would have $ as a currency symbol, while in `:en-GB`, you would have £. Nothing stops you from separating regional and other settings in this way: you just have to provide full "English - United Kingdom" locale in a `:en-GB` dictionary. Few gems such as [Globalize3](https://github.com/globalize/globalize) may help you implement it.
 
 The **translations load path** (`I18n.load_path`) is an array of paths to files that will be loaded automatically. Configuring this path allows for customization of translations directory structure and file naming scheme.
 
@@ -124,6 +126,9 @@ The load path must be specified before any translations are looked up. To change
 # Where the I18n library should search for translation files
 I18n.load_path += Dir[Rails.root.join('lib', 'locale', '*.{rb,yml}')]
 
+# Whitelist locales available for the application
+I18n.available_locales = [:en, :pt]
+
 # Set default locale to something other than :en
 I18n.default_locale = :pt
 ```
@@ -166,7 +171,7 @@ def set_locale
   I18n.locale = extract_locale_from_tld || I18n.default_locale
 end
 
-# Get locale from top-level domain or return nil if such locale is not available
+# Get locale from top-level domain or return +nil+ if such locale is not available
 # You have to put something like:
 #   127.0.0.1 application.com
 #   127.0.0.1 application.it
@@ -305,10 +310,10 @@ In general, this approach is far less reliable than using the language header an
 
 #### Storing the Locale from the Session or Cookies
 
-WARNING: You may be tempted to store the chosen locale in a _session_ or a *cookie*. However, **do not do this**. The locale should be transparent and a part of the URL. This way you won't break people's basic assumptions about the web itself: if you send a URL to a friend, they should see the same page and content as you. A fancy word for this would be that you're being [*RESTful*](http://en.wikipedia.org/wiki/Representational_State_Transfer). Read more about the RESTful approach in [Stefan Tilkov's articles](http://www.infoq.com/articles/rest-introduction). Sometimes there are exceptions to this rule and those are discussed below.
+WARNING: You may be tempted to store the chosen locale in a _session_ or a *cookie*. However, **do not do this**. The locale should be transparent and a part of the URL. This way you won't break people's basic assumptions about the web itself: if you send a URL to a friend, they should see the same page and content as you. A fancy word for this would be that you're being [*RESTful*](https://en.wikipedia.org/wiki/Representational_State_Transfer). Read more about the RESTful approach in [Stefan Tilkov's articles](https://www.infoq.com/articles/rest-introduction). Sometimes there are exceptions to this rule and those are discussed below.
 
 Internationalization and Localization
------------------------------------
+-------------------------------------
 
 OK! Now you've initialized I18n support for your Ruby on Rails application and told it which locale to use and how to preserve it between requests.
 
@@ -366,7 +371,7 @@ end
 
 ```html+erb
 # app/views/home/index.html.erb
-<h1><%=t :hello_world %></h1>
+<h1><%= t :hello_world %></h1>
 <p><%= flash[:notice] %></p>
 ```
 
@@ -404,6 +409,35 @@ NOTE: You need to restart the server when you add new locale files.
 
 You may use YAML (`.yml`) or plain Ruby (`.rb`) files for storing your translations in SimpleStore. YAML is the preferred option among Rails developers. However, it has one big disadvantage. YAML is very sensitive to whitespace and special characters, so the application may not load your dictionary properly. Ruby files will crash your application on first request, so you may easily find what's wrong. (If you encounter any "weird issues" with YAML dictionaries, try putting the relevant portion of your dictionary into a Ruby file.)
 
+If your translations are stored in YAML files, certain keys must be escaped. They are:
+
+* true, on, yes
+* false, off, no
+
+Examples:
+
+```yaml
+# config/locales/en.yml
+en:
+  success:
+    'true':  'True!'
+    'on':    'On!'
+    'false': 'False!'
+  failure:
+    true:    'True!'
+    off:     'Off!'
+    false:   'False!'
+```
+
+```ruby
+I18n.t 'success.true'  # => 'True!'
+I18n.t 'success.on'    # => 'On!'
+I18n.t 'success.false' # => 'False!'
+I18n.t 'failure.false' # => Translation Missing
+I18n.t 'failure.off'   # => Translation Missing
+I18n.t 'failure.true'  # => Translation Missing
+```
+
 ### Passing Variables to Translations
 
 One key consideration for successfully internationalizing an application is to
@@ -468,7 +502,7 @@ OK! Now let's add a timestamp to the view, so we can demo the **date/time locali
 
 ```erb
 # app/views/home/index.html.erb
-<h1><%=t :hello_world %></h1>
+<h1><%= t :hello_world %></h1>
 <p><%= flash[:notice] %></p>
 <p><%= l Time.now, format: :short %></p>
 ```
@@ -667,12 +701,15 @@ end
 
 ### Pluralization
 
-In English there are only one singular and one plural form for a given string, e.g. "1 message" and "2 messages". Other languages ([Arabic](http://unicode.org/repos/cldr-tmp/trunk/diff/supplemental/language_plural_rules.html#ar), [Japanese](http://unicode.org/repos/cldr-tmp/trunk/diff/supplemental/language_plural_rules.html#ja), [Russian](http://unicode.org/repos/cldr-tmp/trunk/diff/supplemental/language_plural_rules.html#ru) and many more) have different grammars that have additional or fewer [plural forms](http://unicode.org/repos/cldr-tmp/trunk/diff/supplemental/language_plural_rules.html). Thus, the I18n API provides a flexible pluralization feature.
+In many languages — including English — there are only two forms, a singular and a plural, for
+a given string, e.g. "1 message" and "2 messages". Other languages ([Arabic](http://www.unicode.org/cldr/charts/latest/supplemental/language_plural_rules.html#ar), [Japanese](http://www.unicode.org/cldr/charts/latest/supplemental/language_plural_rules.html#ja), [Russian](http://www.unicode.org/cldr/charts/latest/supplemental/language_plural_rules.html#ru) and many more) have different grammars that have additional or fewer [plural forms](http://cldr.unicode.org/index/cldr-spec/plural-rules). Thus, the I18n API provides a flexible pluralization feature.
 
-The `:count` interpolation variable has a special role in that it both is interpolated to the translation and used to pick a pluralization from the translations according to the pluralization rules defined by CLDR:
+The `:count` interpolation variable has a special role in that it both is interpolated to the translation and used to pick a pluralization from the translations according to the pluralization rules defined in the
+pluralization backend. By default, only the English pluralization rules are applied.
 
 ```ruby
 I18n.backend.store_translations :en, inbox: {
+  zero: 'no messages', # optional
   one: 'one message',
   other: '%{count} messages'
 }
@@ -681,18 +718,39 @@ I18n.translate :inbox, count: 2
 
 I18n.translate :inbox, count: 1
 # => 'one message'
+
+I18n.translate :inbox, count: 0
+# => 'no messages'
 ```
 
 The algorithm for pluralizations in `:en` is as simple as:
 
 ```ruby
-entry[count == 1 ? 0 : 1]
+lookup_key = :zero if count == 0 && entry.has_key?(:zero)
+lookup_key ||= count == 1 ? :one : :other
+entry[lookup_key]
 ```
 
-I.e. the translation denoted as `:one` is regarded as singular, the other is used as plural (including the count being zero).
+The translation denoted as `:one` is regarded as singular, and the `:other` is used as plural. If the count is zero, and a `:zero` entry is present, then it will be used instead of `:other`.
 
 If the lookup for the key does not return a Hash suitable for pluralization, an `I18n::InvalidPluralizationData` exception is raised.
 
+#### Locale-specific rules
+
+The I18n gem provides a Pluralization backend that can be used to enable locale-specific rules. Include it
+to the Simple backend, then add the localized pluralization algorithms to translation store, as `i18n.plural.rule`.
+
+```ruby
+I18n::Backend::Simple.include(I18n::Backend::Pluralization)
+I18n.backend.store_translations :pt, i18n: { plural: { rule: lambda { |n| [0, 1].include?(n) ? :one : :other } } }
+I18n.backend.store_translations :pt, apples: { one: 'one or none', other: 'more than one' }
+
+I18n.t :apples, count: 0, locale: :pt
+# => 'one or none'
+```
+
+Alternatively, the separate gem [rails-i18n](https://github.com/svenfuchs/rails-i18n) can be used to provide a fuller set of locale-specific pluralization rules.
+
 ### Setting and Passing a Locale
 
 The locale can be either set pseudo-globally to `I18n.locale` (which uses `Thread.current` like, e.g., `Time.zone`) or can be passed as an option to `#translate` and `#localize`.
@@ -866,7 +924,7 @@ This way you can provide special translations for various error messages at diff
 
 #### Error Message Interpolation
 
-The translated model name, translated attribute name, and value are always available for interpolation.
+The translated model name, translated attribute name, and value are always available for interpolation as `model`, `attribute` and `value` respectively.
 
 So, for example, instead of the default error message `"cannot be blank"` you could use the attribute name like this : `"Please fill in your %{attribute}"`.
 
@@ -888,6 +946,7 @@ So, for example, instead of the default error message `"cannot be blank"` you co
 | inclusion    | -                         | :inclusion                | -             |
 | exclusion    | -                         | :exclusion                | -             |
 | associated   | -                         | :invalid                  | -             |
+| non-optional association | -             | :required                 | -             |
 | numericality | -                         | :not_a_number             | -             |
 | numericality | :greater_than             | :greater_than             | count         |
 | numericality | :greater_than_or_equal_to | :greater_than_or_equal_to | count         |
@@ -918,7 +977,7 @@ en:
 ```
 
 NOTE: In order to use this helper, you need to install [DynamicForm](https://github.com/joelmoss/dynamic_form)
-gem by adding this line to your Gemfile: `gem 'dynamic_form'`.
+gem by adding this line to your `Gemfile`: `gem 'dynamic_form'`.
 
 ### Translations for Action Mailer E-Mail Subjects
 
@@ -991,7 +1050,7 @@ The Simple backend shipped with Active Support allows you to store translations
 
 For example a Ruby Hash providing translations can look like this:
 
-```yaml
+```ruby
 {
   pt: {
     foo: {
@@ -1112,7 +1171,7 @@ Conclusion
 
 At this point you should have a good overview about how I18n support in Ruby on Rails works and are ready to start translating your project.
 
-If you want to discuss certain portions or have questions, please sign up to the [rails-i18n mailing list](http://groups.google.com/group/rails-i18n).
+If you want to discuss certain portions or have questions, please sign up to the [rails-i18n mailing list](https://groups.google.com/forum/#!forum/rails-i18n).
 
 
 Contributing to Rails I18n
@@ -1120,15 +1179,15 @@ Contributing to Rails I18n
 
 I18n support in Ruby on Rails was introduced in the release 2.2 and is still evolving. The project follows the good Ruby on Rails development tradition of evolving solutions in gems and real applications first, and only then cherry-picking the best-of-breed of most widely useful features for inclusion in the core.
 
-Thus we encourage everybody to experiment with new ideas and features in gems or other libraries and make them available to the community. (Don't forget to announce your work on our [mailing list](http://groups.google.com/group/rails-i18n!))
+Thus we encourage everybody to experiment with new ideas and features in gems or other libraries and make them available to the community. (Don't forget to announce your work on our [mailing list](https://groups.google.com/forum/#!forum/rails-i18n)!)
 
-If you find your own locale (language) missing from our [example translations data](https://github.com/svenfuchs/rails-i18n/tree/master/rails/locale) repository for Ruby on Rails, please [_fork_](https://github.com/guides/fork-a-project-and-submit-your-modifications) the repository, add your data and send a [pull request](https://github.com/guides/pull-requests).
+If you find your own locale (language) missing from our [example translations data](https://github.com/svenfuchs/rails-i18n/tree/master/rails/locale) repository for Ruby on Rails, please [_fork_](https://github.com/guides/fork-a-project-and-submit-your-modifications) the repository, add your data and send a [pull request](https://help.github.com/articles/about-pull-requests/).
 
 
 Resources
 ---------
 
-* [Google group: rails-i18n](http://groups.google.com/group/rails-i18n) - The project's mailing list.
+* [Google group: rails-i18n](https://groups.google.com/forum/#!forum/rails-i18n) - The project's mailing list.
 * [GitHub: rails-i18n](https://github.com/svenfuchs/rails-i18n) - Code repository and issue tracker for the rails-i18n project. Most importantly you can find lots of [example translations](https://github.com/svenfuchs/rails-i18n/tree/master/rails/locale) for Rails that should work for your application in most cases.
 * [GitHub: i18n](https://github.com/svenfuchs/i18n) - Code repository and issue tracker for the i18n gem.
 
@@ -1142,7 +1201,7 @@ Authors
 Footnotes
 ---------
 
-[^1]: Or, to quote [Wikipedia](http://en.wikipedia.org/wiki/Internationalization_and_localization): _"Internationalization is the process of designing a software application so that it can be adapted to various languages and regions without engineering changes. Localization is the process of adapting software for a specific region or language by adding locale-specific components and translating text."_
+[^1]: Or, to quote [Wikipedia](https://en.wikipedia.org/wiki/Internationalization_and_localization): _"Internationalization is the process of designing a software application so that it can be adapted to various languages and regions without engineering changes. Localization is the process of adapting software for a specific region or language by adding locale-specific components and translating text."_
 
 [^2]: Other backends might allow or require to use other formats, e.g. a GetText backend might allow to read GetText files.
 
diff --git a/guides/source/initialization.md b/guides/source/initialization.md
index 89e5346d86..c4f1df487b 100644
--- a/guides/source/initialization.md
+++ b/guides/source/initialization.md
@@ -16,7 +16,7 @@ After reading this guide, you will know:
 --------------------------------------------------------------------------------
 
 This guide goes through every method call that is
-required to boot up the Ruby on Rails stack for a default Rails 4
+required to boot up the Ruby on Rails stack for a default Rails
 application, explaining each part in detail along the way. For this
 guide, we will be focusing on what happens when you execute `rails server`
 to boot your app.
@@ -74,7 +74,7 @@ This file is as follows:
 
 ```ruby
 #!/usr/bin/env ruby
-APP_PATH = File.expand_path('../../config/application', __FILE__)
+APP_PATH = File.expand_path('../config/application', __dir__)
 require_relative '../config/boot'
 require 'rails/commands'
 ```
@@ -86,36 +86,36 @@ The `APP_PATH` constant will be used later in `rails/commands`. The `config/boot
 `config/boot.rb` contains:
 
 ```ruby
-ENV['BUNDLE_GEMFILE'] ||= File.expand_path('../../Gemfile', __FILE__)
+ENV['BUNDLE_GEMFILE'] ||= File.expand_path('../Gemfile', __dir__)
 
 require 'bundler/setup' # Set up gems listed in the Gemfile.
 ```
 
 In a standard Rails application, there's a `Gemfile` which declares all
 dependencies of the application. `config/boot.rb` sets
-`ENV['BUNDLE_GEMFILE']` to the location of this file. If the Gemfile
+`ENV['BUNDLE_GEMFILE']` to the location of this file. If the `Gemfile`
 exists, then `bundler/setup` is required. The require is used by Bundler to
 configure the load path for your Gemfile's dependencies.
 
 A standard Rails application depends on several gems, specifically:
 
+* actioncable
 * actionmailer
 * actionpack
 * actionview
+* activejob
 * activemodel
 * activerecord
+* activestorage
 * activesupport
-* activejob
 * arel
 * builder
 * bundler
-* erubis
+* erubi
 * i18n
 * mail
 * mime-types
 * rack
-* rack-cache
-* rack-mount
 * rack-test
 * rails
 * railties
@@ -131,7 +131,7 @@ Once `config/boot.rb` has finished, the next file that is required is
 `ARGV` array simply contains `server` which will be passed over:
 
 ```ruby
-ARGV << '--help' if ARGV.empty?
+require_relative "command"
 
 aliases = {
   "g"  => "generate",
@@ -146,33 +146,37 @@ aliases = {
 command = ARGV.shift
 command = aliases[command] || command
 
-require 'rails/commands/commands_tasks'
-
-Rails::CommandsTasks.new(ARGV).run_command!(command)
+Rails::Command.invoke command, ARGV
 ```
 
-TIP: As you can see, an empty ARGV list will make Rails show the help
-snippet.
-
 If we had used `s` rather than `server`, Rails would have used the `aliases`
 defined here to find the matching command.
 
-### `rails/commands/commands_tasks.rb`
+### `rails/command.rb`
 
-When one types a valid Rails command, `run_command!` a method of the same name
-is called. If Rails doesn't recognize the command, it tries to run a Rake task
-of the same name.
+When one types a Rails command, `invoke` tries to lookup a command for the given
+namespace and executes the command if found.
 
-```ruby
-COMMAND_WHITELIST = %w(plugin generate destroy console server dbconsole application runner new version help)
+If Rails doesn't recognize the command, it hands the reins over to Rake
+to run a task of the same name.
+
+As shown, `Rails::Command` displays the help output automatically if the `args`
+are empty.
 
-def run_command!(command)
-  command = parse_command(command)
+```ruby
+module Rails::Command
+  class << self
+    def invoke(namespace, args = [], **config)
+      namespace = namespace.to_s
+      namespace = "help" if namespace.blank? || HELP_MAPPINGS.include?(namespace)
+      namespace = "version" if %w( -v --version ).include? namespace
 
-  if COMMAND_WHITELIST.include?(command)
-    send(command)
-  else
-    run_rake_task(command)
+      if command = find_by_namespace(namespace)
+        command.perform(namespace, args, config)
+      else
+        find_by_namespace("rake").perform(namespace, args, config)
+      end
+    end
   end
 end
 ```
@@ -180,53 +184,39 @@ end
 With the `server` command, Rails will further run the following code:
 
 ```ruby
-def set_application_directory!
-  Dir.chdir(File.expand_path('../../', APP_PATH)) unless File.exist?(File.expand_path("config.ru"))
-end
-
-def server
-  set_application_directory!
-  require_command!("server")
-
-  Rails::Server.new.tap do |server|
-    # We need to require application after the server sets environment,
-    # otherwise the --environment option given to the server won't propagate.
-    require APP_PATH
-    Dir.chdir(Rails.application.root)
-    server.start
+module Rails
+  module Command
+    class ServerCommand < Base # :nodoc:
+      def perform
+        set_application_directory!
+
+        Rails::Server.new.tap do |server|
+          # Require application after server sets environment to propagate
+          # the --environment option.
+          require APP_PATH
+          Dir.chdir(Rails.application.root)
+          server.start
+        end
+      end
+    end
   end
 end
-
-def require_command!(command)
-  require "rails/commands/#{command}"
-end
 ```
 
 This file will change into the Rails root directory (a path two directories up
 from `APP_PATH` which points at `config/application.rb`), but only if the
-`config.ru` file isn't found. This then requires `rails/commands/server` which
-sets up the `Rails::Server` class.
-
-```ruby
-require 'fileutils'
-require 'optparse'
-require 'action_dispatch'
-require 'rails'
-
-module Rails
-  class Server < ::Rack::Server
-```
-
-`fileutils` and `optparse` are standard Ruby libraries which provide helper functions for working with files and parsing options.
+`config.ru` file isn't found. This then starts up the `Rails::Server` class.
 
 ### `actionpack/lib/action_dispatch.rb`
 
 Action Dispatch is the routing component of the Rails framework.
 It adds functionality like routing, session, and common middlewares.
 
-### `rails/commands/server.rb`
+### `rails/commands/server/server_command.rb`
 
-The `Rails::Server` class is defined in this file by inheriting from `Rack::Server`. When `Rails::Server.new` is called, this calls the `initialize` method in `rails/commands/server.rb`:
+The `Rails::Server` class is defined in this file by inheriting from
+`Rack::Server`. When `Rails::Server.new` is called, this calls the `initialize`
+method in `rails/commands/server/server_command.rb`:
 
 ```ruby
 def initialize(*)
@@ -252,7 +242,10 @@ end
 
 In this case, `options` will be `nil` so nothing happens in this method.
 
-After `super` has finished in `Rack::Server`, we jump back to `rails/commands/server.rb`. At this point, `set_environment` is called within the context of the `Rails::Server` object and this method doesn't appear to do much at first glance:
+After `super` has finished in `Rack::Server`, we jump back to
+`rails/commands/server/server_command.rb`. At this point, `set_environment`
+is called within the context of the `Rails::Server` object and this method
+doesn't appear to do much at first glance:
 
 ```ruby
 def set_environment
@@ -289,17 +282,15 @@ With the `default_options` set to this:
 
 ```ruby
 def default_options
-  environment  = ENV['RACK_ENV'] || 'development'
-  default_host = environment == 'development' ? 'localhost' : '0.0.0.0'
-
-  {
-    :environment => environment,
-    :pid         => nil,
-    :Port        => 9292,
-    :Host        => default_host,
-    :AccessLog   => [],
-    :config      => "config.ru"
-  }
+  super.merge(
+    Port:               ENV.fetch("PORT", 3000).to_i,
+    Host:               ENV.fetch("HOST", "localhost").dup,
+    DoNotReverseLookup: true,
+    environment:        (ENV["RAILS_ENV"] || ENV["RACK_ENV"] || "development").dup,
+    daemonize:          false,
+    caching:            nil,
+    pid:                Options::DEFAULT_PID_PATH,
+    restart_cmd:        restart_command)
 end
 ```
 
@@ -311,22 +302,25 @@ def opt_parser
 end
 ```
 
-The class **is** defined in `Rack::Server`, but is overwritten in `Rails::Server` to take different arguments. Its `parse!` method begins like this:
+The class **is** defined in `Rack::Server`, but is overwritten in
+`Rails::Server` to take different arguments. Its `parse!` method looks
+like this:
 
 ```ruby
 def parse!(args)
   args, options = args.dup, {}
 
-  opt_parser = OptionParser.new do |opts|
-    opts.banner = "Usage: rails server [mongrel, thin, etc] [options]"
-    opts.on("-p", "--port=port", Integer,
-            "Runs Rails on the specified port.", "Default: 3000") { |v| options[:Port] = v }
-  ...
+  option_parser(options).parse! args
+
+  options[:log_stdout] = options[:daemonize].blank? && (options[:environment] || Rails.env) == "development"
+  options[:server]     = args.shift
+  options
+end
 ```
 
 This method will set up keys for the `options` which Rails will then be
 able to use to determine how its server should run. After `initialize`
-has finished, we jump back into `rails/server` where `APP_PATH` (which was
+has finished, we jump back into the server command where `APP_PATH` (which was
 set earlier) is required.
 
 ### `config/application`
@@ -345,6 +339,7 @@ def start
   print_boot_information
   trap(:INT) { exit }
   create_tmp_directories
+  setup_dev_caching
   log_to_stdout if options[:log_stdout]
 
   super
@@ -352,7 +347,6 @@ def start
 end
 
 private
-
   def print_boot_information
     ...
     puts "=> Run `rails server -h` for more startup options"
@@ -364,21 +358,30 @@ private
     end
   end
 
+  def setup_dev_caching
+    if options[:environment] == "development"
+      Rails::DevCaching.enable_by_argument(options[:caching])
+    end
+  end
+
   def log_to_stdout
     wrapped_app # touch the app so the logger is set up
 
-    console = ActiveSupport::Logger.new($stdout)
+    console = ActiveSupport::Logger.new(STDOUT)
     console.formatter = Rails.logger.formatter
     console.level = Rails.logger.level
 
-    Rails.logger.extend(ActiveSupport::Logger.broadcast(console))
+    unless ActiveSupport::Logger.logger_outputs_to?(Rails.logger, STDOUT)
+      Rails.logger.extend(ActiveSupport::Logger.broadcast(console))
+    end
   end
 ```
 
 This is where the first output of the Rails initialization happens. This method
 creates a trap for `INT` signals, so if you `CTRL-C` the server, it will exit the
 process. As we can see from the code here, it will create the `tmp/cache`,
-`tmp/pids`, and `tmp/sockets` directories. It then calls `wrapped_app` which is
+`tmp/pids`, and `tmp/sockets` directories. It then enables caching in development
+if `rails server` is called with `--dev-caching`. Finally, it calls `wrapped_app` which is
 responsible for creating the Rack app, before creating and assigning an instance
 of `ActiveSupport::Logger`.
 
@@ -464,7 +467,7 @@ The `options[:config]` value defaults to `config.ru` which contains this:
 ```ruby
 # This file is used by Rack-based servers to start the application.
 
-require ::File.expand_path('../config/environment', __FILE__)
+require_relative 'config/environment'
 run <%= app_const %>
 ```
 
@@ -485,7 +488,7 @@ end
 The `initialize` method of `Rack::Builder` will take the block here and execute it within an instance of `Rack::Builder`. This is where the majority of the initialization process of Rails happens. The `require` line for `config/environment.rb` in `config.ru` is the first to run:
 
 ```ruby
-require ::File.expand_path('../config/environment', __FILE__)
+require_relative 'config/environment'
 ```
 
 ### `config/environment.rb`
@@ -495,7 +498,7 @@ This file is the common file required by `config.ru` (`rails server`) and Passen
 This file begins with requiring `config/application.rb`:
 
 ```ruby
-require File.expand_path('../application', __FILE__)
+require_relative 'application'
 ```
 
 ### `config/application.rb`
@@ -503,7 +506,7 @@ require File.expand_path('../application', __FILE__)
 This file requires `config/boot.rb`:
 
 ```ruby
-require File.expand_path('../boot', __FILE__)
+require_relative 'boot'
 ```
 
 But only if it hasn't been required before, which would be the case in `rails server`
@@ -534,11 +537,12 @@ require "rails"
   action_mailer/railtie
   active_job/railtie
   action_cable/engine
+  active_storage/engine
   rails/test_unit/railtie
   sprockets/railtie
 ).each do |railtie|
   begin
-    require "#{railtie}"
+    require railtie
   rescue LoadError
   end
 end
@@ -663,7 +667,7 @@ DEFAULT_OPTIONS = {
 }
 
 def self.run(app, options = {})
-  options  = DEFAULT_OPTIONS.merge(options)
+  options = DEFAULT_OPTIONS.merge(options)
 
   if options[:Verbose]
     app = Rack::CommonLogger.new(app, STDOUT)
diff --git a/guides/source/kindle/rails_guides.opf.erb b/guides/source/kindle/rails_guides.opf.erb
index 547abcbc19..63eeb007d7 100644
--- a/guides/source/kindle/rails_guides.opf.erb
+++ b/guides/source/kindle/rails_guides.opf.erb
@@ -5,7 +5,7 @@
   <meta name="cover" content="cover" />
   <dc-metadata xmlns:dc="http://purl.org/dc/elements/1.1/">
 
-  	<dc:title>Ruby on Rails Guides (<%= @version %>)</dc:title>
+       <dc:title>Ruby on Rails Guides (<%= @version || "master@#{@edge[0, 7]}" %>)</dc:title>
 
   	<dc:language>en-us</dc:language>
   	<dc:creator>Ruby on Rails</dc:creator>
diff --git a/guides/source/kindle/toc.html.erb b/guides/source/kindle/toc.html.erb
index f310edd3a1..0f4228ed6b 100644
--- a/guides/source/kindle/toc.html.erb
+++ b/guides/source/kindle/toc.html.erb
@@ -14,7 +14,7 @@ Ruby on Rails Guides
         <% if document['work_in_progress']%>(WIP)<% end %>
       </li>
     <% end %>
-  </ul>  
+  </ul>
 <% end %>
 <hr />
 <ul>
diff --git a/guides/source/layout.html.erb b/guides/source/layout.html.erb
index 9abb863da6..3981199e95 100644
--- a/guides/source/layout.html.erb
+++ b/guides/source/layout.html.erb
@@ -32,7 +32,7 @@
         <li class="more-info"><a href="http://weblog.rubyonrails.org/">Blog</a></li>
         <li class="more-info"><a href="http://guides.rubyonrails.org/">Guides</a></li>
         <li class="more-info"><a href="http://api.rubyonrails.org/">API</a></li>
-        <li class="more-info"><a href="http://stackoverflow.com/questions/tagged/ruby-on-rails">Ask for help</a></li>
+        <li class="more-info"><a href="https://stackoverflow.com/questions/tagged/ruby-on-rails">Ask for help</a></li>
         <li class="more-info"><a href="https://github.com/rails/rails">Contribute on GitHub</a></li>
       </ul>
     </div>
@@ -88,7 +88,7 @@
   <div id="container">
     <div class="wrapper">
       <div id="mainCol">
-        <%= yield.html_safe %>
+        <%= yield %>
 
         <h3>Feedback</h3>
         <p>
@@ -99,9 +99,9 @@
           To get started, you can read our <%= link_to 'documentation contributions', 'http://edgeguides.rubyonrails.org/contributing_to_ruby_on_rails.html#contributing-to-the-rails-documentation' %> section.
         </p>
         <p>
-          You may also find incomplete content, or stuff that is not up to date.
+          You may also find incomplete content or stuff that is not up to date.
           Please do add any missing documentation for master. Make sure to check
-          <%= link_to 'Edge Guides','http://edgeguides.rubyonrails.org' %> first to verify
+          <%= link_to 'Edge Guides', 'http://edgeguides.rubyonrails.org' %> first to verify
           if the issues are already fixed or not on the master branch.
           Check the <%= link_to 'Ruby on Rails Guides Guidelines', 'ruby_on_rails_guides_guidelines.html' %>
           for style and conventions.
@@ -111,7 +111,7 @@
           <%= link_to 'open an issue', 'https://github.com/rails/rails/issues' %>.
         </p>
         <p>And last but not least, any kind of discussion regarding Ruby on Rails
-          documentation is very welcome in the <%= link_to 'rubyonrails-docs mailing list', 'https://groups.google.com/forum/#!forum/rubyonrails-docs' %>.
+          documentation is very welcome on the <%= link_to 'rubyonrails-docs mailing list', 'https://groups.google.com/forum/#!forum/rubyonrails-docs' %>.
         </p>
       </div>
     </div>
@@ -127,13 +127,11 @@
   <script type="text/javascript" src="javascripts/jquery.min.js"></script>
   <script type="text/javascript" src="javascripts/responsive-tables.js"></script>
   <script type="text/javascript" src="javascripts/guides.js"></script>
-  <script type="text/javascript" src="javascripts/syntaxhighlighter/shCore.js"></script>
-  <script type="text/javascript" src="javascripts/syntaxhighlighter/shBrushRuby.js"></script>
-  <script type="text/javascript" src="javascripts/syntaxhighlighter/shBrushXml.js"></script>
-  <script type="text/javascript" src="javascripts/syntaxhighlighter/shBrushSql.js"></script>
-  <script type="text/javascript" src="javascripts/syntaxhighlighter/shBrushPlain.js"></script>
+  <script type="text/javascript" src="javascripts/syntaxhighlighter.js"></script>
   <script type="text/javascript">
-    SyntaxHighlighter.all();
+    syntaxhighlighterConfig = {
+      autoLinks: false,
+    };
     $(guidesIndex.bind);
   </script>
 </body>
diff --git a/guides/source/layouts_and_rendering.md b/guides/source/layouts_and_rendering.md
index 2722789c49..4d79b2db89 100644
--- a/guides/source/layouts_and_rendering.md
+++ b/guides/source/layouts_and_rendering.md
@@ -71,23 +71,25 @@ If we want to display the properties of all the books in our view, we can do so
 <h1>Listing Books</h1>
 
 <table>
-  <tr>
-    <th>Title</th>
-    <th>Summary</th>
-    <th></th>
-    <th></th>
-    <th></th>
-  </tr>
-
-<% @books.each do |book| %>
-  <tr>
-    <td><%= book.title %></td>
-    <td><%= book.content %></td>
-    <td><%= link_to "Show", book %></td>
-    <td><%= link_to "Edit", edit_book_path(book) %></td>
-    <td><%= link_to "Remove", book, method: :delete, data: { confirm: "Are you sure?" } %></td>
-  </tr>
-<% end %>
+  <thead>
+    <tr>
+      <th>Title</th>
+      <th>Content</th>
+      <th colspan="3"></th>
+    </tr>
+  </thead>
+
+  <tbody>
+    <% @books.each do |book| %>
+      <tr>
+        <td><%= book.title %></td>
+        <td><%= book.content %></td>
+        <td><%= link_to "Show", book %></td>
+        <td><%= link_to "Edit", edit_book_path(book) %></td>
+        <td><%= link_to "Destroy", book, method: :delete, data: { confirm: "Are you sure?" } %></td>
+      </tr>
+    <% end %>
+  </tbody>
 </table>
 
 <br>
@@ -221,7 +223,7 @@ service requests that are expecting something other than proper HTML.
 
 NOTE: By default, if you use the `:plain` option, the text is rendered without
 using the current layout. If you want Rails to put the text into the current
-layout, you need to add the `layout: true` option and use the `.txt.erb`
+layout, you need to add the `layout: true` option and use the `.text.erb`
 extension for the layout file.
 
 #### Rendering HTML
@@ -230,14 +232,14 @@ You can send an HTML string back to the browser by using the `:html` option to
 `render`:
 
 ```ruby
-render html: "<strong>Not Found</strong>".html_safe
+render html: helpers.tag.strong('Not Found')
 ```
 
 TIP: This is useful when you're rendering a small snippet of HTML code.
 However, you might want to consider moving it to a template file if the markup
 is complex.
 
-NOTE: When using `html:` option, HTML entities will be escaped if the string is not marked as HTML safe by using `html_safe` method.
+NOTE: When using `html:` option, HTML entities will be escaped if the string is not composed with `html_safe`-aware APIs.
 
 #### Rendering JSON
 
@@ -283,7 +285,7 @@ the response. Using `:plain` or `:html` might be more appropriate most of the
 time.
 
 NOTE: Unless overridden, your response returned from this render option will be
-`text/html`, as that is the default content type of Action Dispatch response.
+`text/plain`, as that is the default content type of Action Dispatch response.
 
 #### Options for `render`
 
@@ -379,6 +381,7 @@ Rails understands both numeric status codes and the corresponding symbols shown
 |                     | 415              | :unsupported_media_type          |
 |                     | 416              | :range_not_satisfiable           |
 |                     | 417              | :expectation_failed              |
+|                     | 421              | :misdirected_request             |
 |                     | 422              | :unprocessable_entity            |
 |                     | 423              | :locked                          |
 |                     | 424              | :failed_dependency               |
@@ -386,6 +389,7 @@ Rails understands both numeric status codes and the corresponding symbols shown
 |                     | 428              | :precondition_required           |
 |                     | 429              | :too_many_requests               |
 |                     | 431              | :request_header_fields_too_large |
+|                     | 451              | :unavailable_for_legal_reasons   |
 | **Server Error**    | 500              | :internal_server_error           |
 |                     | 501              | :not_implemented                 |
 |                     | 502              | :bad_gateway                     |
@@ -411,6 +415,8 @@ render formats: :xml
 render formats: [:json, :xml]
 ```
 
+If a template with the specified format does not exist an `ActionView::MissingTemplate` error is raised.
+
 #### Finding Layouts
 
 To find the current layout, Rails first looks for a file in `app/views/layouts` with the same base name as the controller. For example, rendering actions from the `PhotosController` class will use `app/views/layouts/photos.html.erb` (or `app/views/layouts/photos.builder`). If there is no such controller-specific layout, Rails will use `app/views/layouts/application.html.erb` or `app/views/layouts/application.builder`. If there is no `.erb` layout, Rails will use a `.builder` layout if one exists. Rails also provides several ways to more precisely assign specific layouts to individual controllers and actions.
@@ -630,6 +636,8 @@ to use in this case.
 redirect_back(fallback_location: root_path)
 ```
 
+NOTE: `redirect_to` and `redirect_back` do not halt and return immediately from method execution, but simply set HTTP responses. Statements occurring after them in a method will be executed. You can halt by an explicit `return` or some other halting mechanism, if needed.
+
 #### Getting a Different Redirect Status Code
 
 Rails uses HTTP status code 302, a temporary redirect, when you call `redirect_to`. If you'd like to use a different status code, perhaps 301, a permanent redirect, you can use the `:status` option:
@@ -749,7 +757,7 @@ When Rails renders a view as a response, it does so by combining the view with t
 
 ### Asset Tag Helpers
 
-Asset tag helpers provide methods for generating HTML that link views to feeds, JavaScript, stylesheets, images, videos and audios. There are six asset tag helpers available in Rails:
+Asset tag helpers provide methods for generating HTML that link views to feeds, JavaScript, stylesheets, images, videos, and audios. There are six asset tag helpers available in Rails:
 
 * `auto_discovery_link_tag`
 * `javascript_include_tag`
@@ -764,7 +772,7 @@ WARNING: The asset tag helpers do _not_ verify the existence of the assets at th
 
 #### Linking to Feeds with the `auto_discovery_link_tag`
 
-The `auto_discovery_link_tag` helper builds HTML that most browsers and feed readers can use to detect the presence of RSS or Atom feeds. It takes the type of the link (`:rss` or `:atom`), a hash of options that are passed through to url_for, and a hash of options for the tag:
+The `auto_discovery_link_tag` helper builds HTML that most browsers and feed readers can use to detect the presence of RSS, Atom, or JSON feeds. It takes the type of the link (`:rss`, `:atom`, or `:json`), a hash of options that are passed through to url_for, and a hash of options for the tag:
 
 ```erb
 <%= auto_discovery_link_tag(:rss, {action: "feed"},
@@ -1080,7 +1088,7 @@ definitions for several similar resources:
 * `shared/_search_filters.html.erb`
 
     ```html+erb
-    <%= form_for(@q) do |f| %>
+    <%= form_for(search) do |f| %>
       <h1>Search form:</h1>
       <fieldset>
         <%= yield f %>
@@ -1153,7 +1161,7 @@ To pass a local variable to a partial in only specific cases use the `local_assi
   <%= render article, full: true %>
   ```
 
-* `_articles.html.erb`
+* `_article.html.erb`
 
   ```erb
   <h2><%= article.title %></h2>
@@ -1167,7 +1175,7 @@ To pass a local variable to a partial in only specific cases use the `local_assi
 
 This way it is possible to use the partial without the need to declare all local variables.
 
-Every partial also has a local variable with the same name as the partial (minus the underscore). You can pass an object in to this local variable via the `:object` option:
+Every partial also has a local variable with the same name as the partial (minus the leading underscore). You can pass an object in to this local variable via the `:object` option:
 
 ```erb
 <%= render partial: "customer", object: @new_customer %>
@@ -1258,7 +1266,7 @@ You can also pass in arbitrary local variables to any partial you are rendering
 
 In this case, the partial will have access to a local variable `title` with the value "Products Page".
 
-TIP: Rails also makes a counter variable available within a partial called by the collection, named after the member of the collection followed by `_counter`. For example, if you're rendering `@products`, within the partial you can refer to `product_counter` to tell you how many times the partial has been rendered. This does not work in conjunction with the `as: :value` option.
+TIP: Rails also makes a counter variable available within a partial called by the collection, named after the title of the partial followed by `_counter`. For example, when rendering a collection `@products` the partial `_product.html.erb` can access the variable `product_counter` which indexes the number of times it has been rendered within the enclosing view.
 
 You can also specify a second partial to be rendered between instances of the main partial by using the `:spacer_template` option:
 
@@ -1278,7 +1286,7 @@ When rendering collections it is also possible to use the `:layout` option:
 <%= render partial: "product", collection: @products, layout: "special_layout" %>
 ```
 
-The layout will be rendered together with the partial for each item in the collection. The current object and object_counter variables will be available in the layout as well, the same way they do within the partial.
+The layout will be rendered together with the partial for each item in the collection. The current object and object_counter variables will be available in the layout as well, the same way they are within the partial.
 
 ### Using Nested Layouts
 
diff --git a/guides/source/maintenance_policy.md b/guides/source/maintenance_policy.md
index f99b6ebd31..1d6a4edb5b 100644
--- a/guides/source/maintenance_policy.md
+++ b/guides/source/maintenance_policy.md
@@ -44,7 +44,7 @@ from.
 In special situations, where someone from the Core Team agrees to support more series,
 they are included in the list of supported series.
 
-**Currently included series:** `5.0.Z`.
+**Currently included series:** `5.1.Z`.
 
 Security Issues
 ---------------
@@ -59,7 +59,7 @@ be built from 1.2.2, and then added to the end of 1-2-stable. This means that
 security releases are easy to upgrade to if you're running the latest version
 of Rails.
 
-**Currently included series:** `5.0.Z`, `4.2.Z`.
+**Currently included series:** `5.1.Z`, `5.0.Z`.
 
 Severe Security Issues
 ----------------------
@@ -68,7 +68,7 @@ For severe security issues we will provide new versions as above, and also the
 last major release series will receive patches and new versions. The
 classification of the security issue is judged by the core team.
 
-**Currently included series:** `5.0.Z`, `4.2.Z`.
+**Currently included series:** `5.1.Z`, `5.0.Z`, `4.2.Z`.
 
 Unsupported Release Series
 --------------------------
diff --git a/guides/source/nested_model_forms.md b/guides/source/nested_model_forms.md
deleted file mode 100644
index 71efa4b0d0..0000000000
--- a/guides/source/nested_model_forms.md
+++ /dev/null
@@ -1,230 +0,0 @@
-**DO NOT READ THIS FILE ON GITHUB, GUIDES ARE PUBLISHED ON http://guides.rubyonrails.org.**
-
-Rails Nested Model Forms
-========================
-
-Creating a form for a model _and_ its associations can become quite tedious. Therefore Rails provides helpers to assist in dealing with the complexities of generating these forms _and_ the required CRUD operations to create, update, and destroy associations.
-
-After reading this guide, you will know:
-
-* do stuff.
-
---------------------------------------------------------------------------------
-
-NOTE: This guide assumes the user knows how to use the [Rails form helpers](form_helpers.html) in general. Also, it's **not** an API reference. For a complete reference please visit [the Rails API documentation](http://api.rubyonrails.org/).
-
-
-Model setup
------------
-
-To be able to use the nested model functionality in your forms, the model will need to support some basic operations.
-
-First of all, it needs to define a writer method for the attribute that corresponds to the association you are building a nested model form for. The `fields_for` form helper will look for this method to decide whether or not a nested model form should be built.
-
-If the associated object is an array, a form builder will be yielded for each object, else only a single form builder will be yielded.
-
-Consider a Person model with an associated Address. When asked to yield a nested FormBuilder for the `:address` attribute, the `fields_for` form helper will look for a method on the Person instance named `address_attributes=`.
-
-### ActiveRecord::Base model
-
-For an ActiveRecord::Base model and association this writer method is commonly defined with the `accepts_nested_attributes_for` class method:
-
-#### has_one
-
-```ruby
-class Person < ApplicationRecord
-  has_one :address
-  accepts_nested_attributes_for :address
-end
-```
-
-#### belongs_to
-
-```ruby
-class Person < ApplicationRecord
-  belongs_to :firm
-  accepts_nested_attributes_for :firm
-end
-```
-
-#### has_many / has_and_belongs_to_many
-
-```ruby
-class Person < ApplicationRecord
-  has_many :projects
-  accepts_nested_attributes_for :projects
-end
-```
-
-NOTE: For greater detail on associations see [Active Record Associations](association_basics.html).
-For a complete reference on associations please visit the API documentation for [ActiveRecord::Associations::ClassMethods](http://api.rubyonrails.org/classes/ActiveRecord/Associations/ClassMethods.html).
-
-### Custom model
-
-As you might have inflected from this explanation, you _don't_ necessarily need an ActiveRecord::Base model to use this functionality. The following examples are sufficient to enable the nested model form behavior:
-
-#### Single associated object
-
-```ruby
-class Person
-  def address
-    Address.new
-  end
-
-  def address_attributes=(attributes)
-    # ...
-  end
-end
-```
-
-#### Association collection
-
-```ruby
-class Person
-  def projects
-    [Project.new, Project.new]
-  end
-
-  def projects_attributes=(attributes)
-    # ...
-  end
-end
-```
-
-NOTE: See (TODO) in the advanced section for more information on how to deal with the CRUD operations in your custom model.
-
-Views
------
-
-### Controller code
-
-A nested model form will _only_ be built if the associated object(s) exist. This means that for a new model instance you would probably want to build the associated object(s) first.
-
-Consider the following typical RESTful controller which will prepare a new Person instance and its `address` and `projects` associations before rendering the `new` template:
-
-```ruby
-class PeopleController < ApplicationController
-  def new
-    @person = Person.new
-    @person.build_address
-    2.times { @person.projects.build }
-  end
-
-  def create
-    @person = Person.new(params[:person])
-    if @person.save
-      # ...
-    end
-  end
-end
-```
-
-NOTE: Obviously the instantiation of the associated object(s) can become tedious and not DRY, so you might want to move that into the model itself. ActiveRecord::Base provides an `after_initialize` callback which is a good way to refactor this.
-
-### Form code
-
-Now that you have a model instance, with the appropriate methods and associated object(s), you can start building the nested model form.
-
-#### Standard form
-
-Start out with a regular RESTful form:
-
-```erb
-<%= form_for @person do |f| %>
-  <%= f.text_field :name %>
-<% end %>
-```
-
-This will generate the following html:
-
-```html
-<form action="/people" class="new_person" id="new_person" method="post">
-  <input id="person_name" name="person[name]" type="text" />
-</form>
-```
-
-#### Nested form for a single associated object
-
-Now add a nested form for the `address` association:
-
-```erb
-<%= form_for @person do |f| %>
-  <%= f.text_field :name %>
-
-  <%= f.fields_for :address do |af| %>
-    <%= af.text_field :street %>
-  <% end %>
-<% end %>
-```
-
-This generates:
-
-```html
-<form action="/people" class="new_person" id="new_person" method="post">
-  <input id="person_name" name="person[name]" type="text" />
-
-  <input id="person_address_attributes_street" name="person[address_attributes][street]" type="text" />
-</form>
-```
-
-Notice that `fields_for` recognized the `address` as an association for which a nested model form should be built by the way it has namespaced the `name` attribute.
-
-When this form is posted the Rails parameter parser will construct a hash like the following:
-
-```ruby
-{
-  "person" => {
-    "name" => "Eloy Duran",
-    "address_attributes" => {
-      "street" => "Nieuwe Prinsengracht"
-    }
-  }
-}
-```
-
-That's it. The controller will simply pass this hash on to the model from the `create` action. The model will then handle building the `address` association for you and automatically save it when the parent (`person`) is saved.
-
-#### Nested form for a collection of associated objects
-
-The form code for an association collection is pretty similar to that of a single associated object:
-
-```erb
-<%= form_for @person do |f| %>
-  <%= f.text_field :name %>
-
-  <%= f.fields_for :projects do |pf| %>
-    <%= pf.text_field :name %>
-  <% end %>
-<% end %>
-```
-
-Which generates:
-
-```html
-<form action="/people" class="new_person" id="new_person" method="post">
-  <input id="person_name" name="person[name]" type="text" />
-
-  <input id="person_projects_attributes_0_name" name="person[projects_attributes][0][name]" type="text" />
-  <input id="person_projects_attributes_1_name" name="person[projects_attributes][1][name]" type="text" />
-</form>
-```
-
-As you can see it has generated 2 `project name` inputs, one for each new `project` that was built in the controller's `new` action. Only this time the `name` attribute of the input contains a digit as an extra namespace. This will be parsed by the Rails parameter parser as:
-
-```ruby
-{
-  "person" => {
-    "name" => "Eloy Duran",
-    "projects_attributes" => {
-      "0" => { "name" => "Project 1" },
-      "1" => { "name" => "Project 2" }
-    }
-  }
-}
-```
-
-You can basically see the `projects_attributes` hash as an array of attribute hashes, one for each model instance.
-
-NOTE: The reason that `fields_for` constructed a hash instead of an array is that it won't work for any form nested deeper than one level deep.
-
-TIP: You _can_ however pass an array to the writer method generated by `accepts_nested_attributes_for` if you're using plain Ruby or some other API access. See (TODO) for more info and example.
diff --git a/guides/source/plugins.md b/guides/source/plugins.md
index 8f055f8fe3..15073af6be 100644
--- a/guides/source/plugins.md
+++ b/guides/source/plugins.md
@@ -30,7 +30,7 @@ Setup
 -----
 
 Currently, Rails plugins are built as gems, _gemified plugins_. They can be shared across
-different rails applications using RubyGems and Bundler if desired.
+different Rails applications using RubyGems and Bundler if desired.
 
 ### Generate a gemified plugin.
 
@@ -67,14 +67,14 @@ This will tell you that everything got generated properly and you are ready to s
 Extending Core Classes
 ----------------------
 
-This section will explain how to add a method to String that will be available anywhere in your rails application.
+This section will explain how to add a method to String that will be available anywhere in your Rails application.
 
 In this example you will add a method to String named `to_squawk`. To begin, create a new test file with a few assertions:
 
 ```ruby
 # yaffle/test/core_ext_test.rb
 
-require 'test_helper'
+require "test_helper"
 
 class CoreExtTest < ActiveSupport::TestCase
   def test_to_squawk_prepends_the_word_squawk
@@ -104,14 +104,16 @@ Finished in 0.003358s, 595.6483 runs/s, 297.8242 assertions/s.
 
 Great - now you are ready to start development.
 
-In `lib/yaffle.rb`, add `require 'yaffle/core_ext'`:
+In `lib/yaffle.rb`, add `require "yaffle/core_ext"`:
 
 ```ruby
 # yaffle/lib/yaffle.rb
 
-require 'yaffle/core_ext'
+require "yaffle/railtie"
+require "yaffle/core_ext"
 
 module Yaffle
+  # Your code goes here...
 end
 ```
 
@@ -120,7 +122,7 @@ Finally, create the `core_ext.rb` file and add the `to_squawk` method:
 ```ruby
 # yaffle/lib/yaffle/core_ext.rb
 
-String.class_eval do
+class String
   def to_squawk
     "squawk! #{self}".strip
   end
@@ -133,7 +135,7 @@ To test that your method does what it says it does, run the unit tests with `bin
   2 runs, 2 assertions, 0 failures, 0 errors, 0 skips
 ```
 
-To see this in action, change to the test/dummy directory, fire up a console and start squawking:
+To see this in action, change to the `test/dummy` directory, fire up a console and start squawking:
 
 ```bash
 $ bin/rails console
@@ -152,7 +154,7 @@ To begin, set up your files so that you have:
 ```ruby
 # yaffle/test/acts_as_yaffle_test.rb
 
-require 'test_helper'
+require "test_helper"
 
 class ActsAsYaffleTest < ActiveSupport::TestCase
 end
@@ -161,10 +163,12 @@ end
 ```ruby
 # yaffle/lib/yaffle.rb
 
-require 'yaffle/core_ext'
-require 'yaffle/acts_as_yaffle'
+require "yaffle/railtie"
+require "yaffle/core_ext"
+require "yaffle/acts_as_yaffle"
 
 module Yaffle
+  # Your code goes here...
 end
 ```
 
@@ -173,7 +177,6 @@ end
 
 module Yaffle
   module ActsAsYaffle
-    # your code will go here
   end
 end
 ```
@@ -189,7 +192,7 @@ To start out, write a failing test that shows the behavior you'd like:
 ```ruby
 # yaffle/test/acts_as_yaffle_test.rb
 
-require 'test_helper'
+require "test_helper"
 
 class ActsAsYaffleTest < ActiveSupport::TestCase
   def test_a_hickwalls_yaffle_text_field_should_be_last_squawk
@@ -234,7 +237,7 @@ Finished in 0.004812s, 831.2949 runs/s, 415.6475 assertions/s.
 
 This tells us that we don't have the necessary models (Hickwall and Wickwall) that we are trying to test.
 We can easily generate these models in our "dummy" Rails application by running the following commands from the
-test/dummy directory:
+`test/dummy` directory:
 
 ```bash
 $ cd test/dummy
@@ -276,12 +279,8 @@ module Yaffle
   module ActsAsYaffle
     extend ActiveSupport::Concern
 
-    included do
-    end
-
-    module ClassMethods
+    class_methods do
       def acts_as_yaffle(options = {})
-        # your code will go here
       end
     end
   end
@@ -335,13 +334,9 @@ module Yaffle
   module ActsAsYaffle
     extend ActiveSupport::Concern
 
-    included do
-    end
-
-    module ClassMethods
+    class_methods do
       def acts_as_yaffle(options = {})
-        cattr_accessor :yaffle_text_field
-        self.yaffle_text_field = (options[:yaffle_text_field] || :last_squawk).to_s
+        cattr_accessor :yaffle_text_field, default: (options[:yaffle_text_field] || :last_squawk).to_s
       end
     end
   end
@@ -364,14 +359,14 @@ When you run `bin/test`, you should see the tests all pass:
 
 ### Add an Instance Method
 
-This plugin will add a method named 'squawk' to any Active Record object that calls 'acts_as_yaffle'. The 'squawk'
+This plugin will add a method named 'squawk' to any Active Record object that calls `acts_as_yaffle`. The 'squawk'
 method will simply set the value of one of the fields in the database.
 
 To start out, write a failing test that shows the behavior you'd like:
 
 ```ruby
 # yaffle/test/acts_as_yaffle_test.rb
-require 'test_helper'
+require "test_helper"
 
 class ActsAsYaffleTest < ActiveSupport::TestCase
   def test_a_hickwalls_yaffle_text_field_should_be_last_squawk
@@ -397,7 +392,7 @@ end
 ```
 
 Run the test to make sure the last two tests fail with an error that contains "NoMethodError: undefined method `squawk'",
-then update 'acts_as_yaffle.rb' to look like this:
+then update `acts_as_yaffle.rb` to look like this:
 
 ```ruby
 # yaffle/lib/yaffle/acts_as_yaffle.rb
@@ -407,20 +402,14 @@ module Yaffle
     extend ActiveSupport::Concern
 
     included do
-    end
-
-    module ClassMethods
-      def acts_as_yaffle(options = {})
-        cattr_accessor :yaffle_text_field
-        self.yaffle_text_field = (options[:yaffle_text_field] || :last_squawk).to_s
-
-        include Yaffle::ActsAsYaffle::LocalInstanceMethods
+      def squawk(string)
+        write_attribute(self.class.yaffle_text_field, string.to_squawk)
       end
     end
 
-    module LocalInstanceMethods
-      def squawk(string)
-        write_attribute(self.class.yaffle_text_field, string.to_squawk)
+    class_methods do
+      def acts_as_yaffle(options = {})
+        cattr_accessor :yaffle_text_field, default: (options[:yaffle_text_field] || :last_squawk).to_s
       end
     end
   end
@@ -450,23 +439,23 @@ send("#{self.class.yaffle_text_field}=", string.to_squawk)
 Generators
 ----------
 
-Generators can be included in your gem simply by creating them in a lib/generators directory of your plugin. More information about
-the creation of generators can be found in the [Generators Guide](generators.html)
+Generators can be included in your gem simply by creating them in a `lib/generators` directory of your plugin. More information about
+the creation of generators can be found in the [Generators Guide](generators.html).
 
 Publishing Your Gem
 -------------------
 
 Gem plugins currently in development can easily be shared from any Git repository. To share the Yaffle gem with others, simply
-commit the code to a Git repository (like GitHub) and add a line to the Gemfile of the application in question:
+commit the code to a Git repository (like GitHub) and add a line to the `Gemfile` of the application in question:
 
 ```ruby
-gem 'yaffle', git: 'git://github.com/yaffle_watcher/yaffle.git'
+gem "yaffle", git: "https://github.com/rails/yaffle.git"
 ```
 
 After running `bundle install`, your gem functionality will be available to the application.
 
-When the gem is ready to be shared as a formal release, it can be published to [RubyGems](http://www.rubygems.org).
-For more information about publishing gems to RubyGems, see: [Creating and Publishing Your First Ruby Gem](http://blog.thepete.net/2010/11/creating-and-publishing-your-first-ruby.html).
+When the gem is ready to be shared as a formal release, it can be published to [RubyGems](https://rubygems.org).
+For more information about publishing gems to RubyGems, see: [Publishing your gem](http://guides.rubygems.org/publishing).
 
 RDoc Documentation
 ------------------
@@ -480,7 +469,7 @@ The first step is to update the README file with detailed information about how
 * How to add the functionality to the app (several examples of common use cases)
 * Warnings, gotchas or tips that might help users and save them time
 
-Once your README is solid, go through and add rdoc comments to all of the methods that developers will use. It's also customary to add '#:nodoc:' comments to those parts of the code that are not included in the public API.
+Once your README is solid, go through and add rdoc comments to all of the methods that developers will use. It's also customary to add `#:nodoc:` comments to those parts of the code that are not included in the public API.
 
 Once your comments are good to go, navigate to your plugin directory and run:
 
diff --git a/guides/source/profiling.md b/guides/source/profiling.md
deleted file mode 100644
index ce093f78ba..0000000000
--- a/guides/source/profiling.md
+++ /dev/null
@@ -1,16 +0,0 @@
-*DO NOT READ THIS FILE ON GITHUB, GUIDES ARE PUBLISHED ON http://guides.rubyonrails.org.**
-
-A Guide to Profiling Rails Applications
-=======================================
-
-This guide covers built-in mechanisms in Rails for profiling your application.
-
-After reading this guide, you will know:
-
-* Rails profiling terminology.
-* How to write benchmark tests for your application.
-* Other benchmarking approaches and plugins.
-
---------------------------------------------------------------------------------
-
-
diff --git a/guides/source/rails_application_templates.md b/guides/source/rails_application_templates.md
index 3e99ee7021..e087834a2f 100644
--- a/guides/source/rails_application_templates.md
+++ b/guides/source/rails_application_templates.md
@@ -277,6 +277,6 @@ relative paths to your template's location.
 
 ```ruby
 def source_paths
-  [File.expand_path(File.dirname(__FILE__))]
+  [__dir__]
 end
 ```
diff --git a/guides/source/rails_on_rack.md b/guides/source/rails_on_rack.md
index 8148f70c31..5718b9ddfc 100644
--- a/guides/source/rails_on_rack.md
+++ b/guides/source/rails_on_rack.md
@@ -20,9 +20,9 @@ Introduction to Rack
 
 Rack provides a minimal, modular and adaptable interface for developing web applications in Ruby. By wrapping HTTP requests and responses in the simplest way possible, it unifies and distills the API for web servers, web frameworks, and software in between (the so-called middleware) into a single method call.
 
-* [Rack API Documentation](http://rack.github.io/)
-
-Explaining Rack is not really in the scope of this guide. In case you are not familiar with Rack's basics, you should check out the [Resources](#resources) section below.
+Explaining how Rack works is not really in the scope of this guide. In case you
+are not familiar with Rack's basics, you should check out the [Resources](#resources)
+section below.
 
 Rails on Rack
 -------------
@@ -64,7 +64,7 @@ To use `rackup` instead of Rails' `rails server`, you can put the following insi
 
 ```ruby
 # Rails.root/config.ru
-require ::File.expand_path('../config/environment', __FILE__)
+require_relative 'config/environment'
 run Rails.application
 ```
 
@@ -74,7 +74,7 @@ And start the server:
 $ rackup config.ru
 ```
 
-To find out more about different `rackup` options:
+To find out more about different `rackup` options, you can run:
 
 ```bash
 $ rackup --help
@@ -89,7 +89,8 @@ Action Dispatcher Middleware Stack
 
 Many of Action Dispatcher's internal components are implemented as Rack middlewares. `Rails::Application` uses `ActionDispatch::MiddlewareStack` to combine various internal and external middlewares to form a complete Rails Rack application.
 
-NOTE: `ActionDispatch::MiddlewareStack` is Rails equivalent of `Rack::Builder`, but built for better flexibility and more features to meet Rails' requirements.
+NOTE: `ActionDispatch::MiddlewareStack` is Rails' equivalent of `Rack::Builder`,
+but is built for better flexibility and more features to meet Rails' requirements.
 
 ### Inspecting Middleware Stack
 
@@ -109,21 +110,23 @@ use ActiveSupport::Cache::Strategy::LocalCache::Middleware
 use Rack::Runtime
 use Rack::MethodOverride
 use ActionDispatch::RequestId
+use ActionDispatch::RemoteIp
+use Sprockets::Rails::QuietAssets
 use Rails::Rack::Logger
 use ActionDispatch::ShowExceptions
 use WebConsole::Middleware
 use ActionDispatch::DebugExceptions
-use ActionDispatch::RemoteIp
 use ActionDispatch::Reloader
 use ActionDispatch::Callbacks
 use ActiveRecord::Migration::CheckPending
 use ActionDispatch::Cookies
 use ActionDispatch::Session::CookieStore
 use ActionDispatch::Flash
+use ActionDispatch::ContentSecurityPolicy::Middleware
 use Rack::Head
 use Rack::ConditionalGet
 use Rack::ETag
-run Rails.application.routes
+run MyApp::Application.routes
 ```
 
 The default middlewares shown here (and some others) are each summarized in the [Internal Middlewares](#internal-middleware-stack) section, below.
@@ -181,7 +184,6 @@ $ bin/rails middleware
 (in /Users/lifo/Rails/blog)
 use ActionDispatch::Static
 use #<ActiveSupport::Cache::Strategy::LocalCache::Middleware:0x00000001c304c8>
-use Rack::Runtime
 ...
 run Rails.application.routes
 ```
@@ -238,9 +240,17 @@ Much of Action Controller's functionality is implemented as Middlewares. The fol
 
 * Makes a unique `X-Request-Id` header available to the response and enables the `ActionDispatch::Request#request_id` method.
 
+**`ActionDispatch::RemoteIp`**
+
+* Checks for IP spoofing attacks.
+
+**`Sprockets::Rails::QuietAssets`**
+
+* Suppresses logger output for asset requests.
+
 **`Rails::Rack::Logger`**
 
-* Notifies the logs that the request has began. After request is complete, flushes all the logs.
+* Notifies the logs that the request has begun. After the request is complete, flushes all the logs.
 
 **`ActionDispatch::ShowExceptions`**
 
@@ -250,10 +260,6 @@ Much of Action Controller's functionality is implemented as Middlewares. The fol
 
 * Responsible for logging exceptions and showing a debugging page in case the request is local.
 
-**`ActionDispatch::RemoteIp`**
-
-* Checks for IP spoofing attacks.
-
 **`ActionDispatch::Reloader`**
 
 * Provides prepare and cleanup callbacks, intended to assist with code reloading during development.
@@ -284,7 +290,7 @@ Much of Action Controller's functionality is implemented as Middlewares. The fol
 
 **`Rack::ConditionalGet`**
 
-* Adds support for "Conditional `GET`" so that server responds with nothing if page wasn't changed.
+* Adds support for "Conditional `GET`" so that server responds with nothing if the page wasn't changed.
 
 **`Rack::ETag`**
 
@@ -297,7 +303,7 @@ Resources
 
 ### Learning Rack
 
-* [Official Rack Website](http://rack.github.io)
+* [Official Rack Website](https://rack.github.io)
 * [Introducing Rack](http://chneukirchen.org/blog/archive/2007/02/introducing-rack.html)
 
 ### Understanding Middlewares
diff --git a/guides/source/routing.md b/guides/source/routing.md
index 756e0fefd7..efc0e32b56 100644
--- a/guides/source/routing.md
+++ b/guides/source/routing.md
@@ -47,7 +47,7 @@ get '/patients/:id', to: 'patients#show', as: 'patient'
 and your application contains this code in the controller:
 
 ```ruby
-@patient = Patient.find(17)
+@patient = Patient.find(params[:id])
 ```
 
 and this in the corresponding view:
@@ -142,16 +142,17 @@ Sometimes, you have a resource that clients always look up without referencing a
 get 'profile', to: 'users#show'
 ```
 
-Passing a `String` to `get` will expect a `controller#action` format, while passing a `Symbol` will map directly to an action but you must also specify the `controller:` to use:
+Passing a `String` to `to:` will expect a `controller#action` format. When using a `Symbol`, the `to:` option should be replaced with `action:`. When using a `String` without a `#`, the `to:` option should be replaced with `controller:`:
 
 ```ruby
-get 'profile', to: :show, controller: 'users'
+get 'profile', action: :show, controller: 'users'
 ```
 
 This resourceful route:
 
 ```ruby
 resource :geocoder
+resolve('Geocoder') { [:geocoder] }
 ```
 
 creates six different routes in your application, all mapping to the `Geocoders` controller:
@@ -175,14 +176,6 @@ A singular resourceful route generates these helpers:
 
 As with plural resources, the same helpers ending in `_url` will also include the host, port and path prefix.
 
-WARNING: A [long-standing bug](https://github.com/rails/rails/issues/1769) prevents `form_for` from working automatically with singular resources. As a workaround, specify the URL for the form directly, like so:
-
-```ruby
-form_for @geocoder, url: geocoder_path do |f|
-
-# snippet for brevity
-```
-
 ### Controller Namespaces and Routing
 
 You may wish to organize groups of controllers under a namespace. Most commonly, you might group a number of administrative controllers under an `Admin::` namespace. You would place these controllers under the `app/controllers/admin` directory, and you can group them together in your router:
@@ -425,7 +418,7 @@ resources :articles do
 end
 ```
 
-Also you can use them in any place that you want inside the routes, for example in a scope or namespace call:
+Also you can use them in any place that you want inside the routes, for example in a `scope` or `namespace` call:
 
 ```ruby
 namespace :articles do
@@ -491,7 +484,7 @@ resources :photos do
 end
 ```
 
-This will recognize `/photos/1/preview` with GET, and route to the `preview` action of `PhotosController`, with the resource id value passed in `params[:id]`. It will also create the `preview_photo_url` and `preview_photo_path` helpers.
+This will recognize `/photos/1/preview` with GET, and route to the `preview` action of `PhotosController`, with the resource id value passed in `params[:id]`. It will also create the `photo_preview_url` and `photo_preview_path` helpers.
 
 Within the block of member routes, each route name specifies the HTTP verb
 will be recognized. You can use `get`, `patch`, `put`, `post`, or `delete` here
@@ -545,7 +538,7 @@ TIP: If you find yourself adding many extra actions to a resourceful route, it's
 Non-Resourceful Routes
 ----------------------
 
-In addition to resource routing, Rails has powerful support for routing arbitrary URLs to actions. Here, you don't get groups of routes automatically generated by resourceful routing. Instead, you set up each route within your application separately.
+In addition to resource routing, Rails has powerful support for routing arbitrary URLs to actions. Here, you don't get groups of routes automatically generated by resourceful routing. Instead, you set up each route separately within your application.
 
 While you should usually use resourceful routing, there are still many places where the simpler routing is more appropriate. There's no need to try to shoehorn every last piece of your application into a resourceful framework if that's not a good fit.
 
@@ -553,29 +546,23 @@ In particular, simple routing makes it very easy to map legacy URLs to new Rails
 
 ### Bound Parameters
 
-When you set up a regular route, you supply a series of symbols that Rails maps to parts of an incoming HTTP request. Two of these symbols are special: `:controller` maps to the name of a controller in your application, and `:action` maps to the name of an action within that controller. For example, consider this route:
+When you set up a regular route, you supply a series of symbols that Rails maps to parts of an incoming HTTP request. For example, consider this route:
 
 ```ruby
-get ':controller(/:action(/:id))'
+get 'photos(/:id)', to: :display
 ```
 
-If an incoming request of `/photos/show/1` is processed by this route (because it hasn't matched any previous route in the file), then the result will be to invoke the `show` action of the `PhotosController`, and to make the final parameter `"1"` available as `params[:id]`. This route will also route the incoming request of `/photos` to `PhotosController#index`, since `:action` and `:id` are optional parameters, denoted by parentheses.
+If an incoming request of `/photos/1` is processed by this route (because it hasn't matched any previous route in the file), then the result will be to invoke the `display` action of the `PhotosController`, and to make the final parameter `"1"` available as `params[:id]`. This route will also route the incoming request of `/photos` to `PhotosController#display`, since `:id` is an optional parameter, denoted by parentheses.
 
 ### Dynamic Segments
 
-You can set up as many dynamic segments within a regular route as you like. Anything other than `:controller` or `:action` will be available to the action as part of `params`. If you set up this route:
+You can set up as many dynamic segments within a regular route as you like. Any segment will be available to the action as part of `params`. If you set up this route:
 
 ```ruby
-get ':controller/:action/:id/:user_id'
+get 'photos/:id/:user_id', to: 'photos#show'
 ```
 
-An incoming path of `/photos/show/1/2` will be dispatched to the `show` action of the `PhotosController`. `params[:id]` will be `"1"`, and `params[:user_id]` will be `"2"`.
-
-NOTE: You can't use `:namespace` or `:module` with a `:controller` path segment. If you need to do this then use a constraint on :controller that matches the namespace you require. e.g:
-
-```ruby
-get ':controller(/:action(/:id))', controller: /admin\/[^\/]+/
-```
+An incoming path of `/photos/1/2` will be dispatched to the `show` action of the `PhotosController`. `params[:id]` will be `"1"`, and `params[:user_id]` will be `"2"`.
 
 TIP: By default, dynamic segments don't accept dots - this is because the dot is used as a separator for formatted routes. If you need to use a dot within a dynamic segment, add a constraint that overrides this – for example, `id: /[^\/]+/` allows anything except a slash.
 
@@ -584,39 +571,39 @@ TIP: By default, dynamic segments don't accept dots - this is because the dot is
 You can specify static segments when creating a route by not prepending a colon to a fragment:
 
 ```ruby
-get ':controller/:action/:id/with_user/:user_id'
+get 'photos/:id/with_user/:user_id', to: 'photos#show'
 ```
 
-This route would respond to paths such as `/photos/show/1/with_user/2`. In this case, `params` would be `{ controller: 'photos', action: 'show', id: '1', user_id: '2' }`.
+This route would respond to paths such as `/photos/1/with_user/2`. In this case, `params` would be `{ controller: 'photos', action: 'show', id: '1', user_id: '2' }`.
 
 ### The Query String
 
 The `params` will also include any parameters from the query string. For example, with this route:
 
 ```ruby
-get ':controller/:action/:id'
+get 'photos/:id', to: 'photos#show'
 ```
 
-An incoming path of `/photos/show/1?user_id=2` will be dispatched to the `show` action of the `Photos` controller. `params` will be `{ controller: 'photos', action: 'show', id: '1', user_id: '2' }`.
+An incoming path of `/photos/1?user_id=2` will be dispatched to the `show` action of the `Photos` controller. `params` will be `{ controller: 'photos', action: 'show', id: '1', user_id: '2' }`.
 
 ### Defining Defaults
 
-You do not need to explicitly use the `:controller` and `:action` symbols within a route. You can supply them as defaults:
+You can define defaults in a route by supplying a hash for the `:defaults` option. This even applies to parameters that you do not specify as dynamic segments. For example:
 
 ```ruby
-get 'photos/:id', to: 'photos#show'
+get 'photos/:id', to: 'photos#show', defaults: { format: 'jpg' }
 ```
 
-With this route, Rails will match an incoming path of `/photos/12` to the `show` action of `PhotosController`.
+Rails would match `photos/12` to the `show` action of `PhotosController`, and set `params[:format]` to `"jpg"`.
 
-You can also define other defaults in a route by supplying a hash for the `:defaults` option. This even applies to parameters that you do not specify as dynamic segments. For example:
+You can also use `defaults` in a block format to define the defaults for multiple items:
 
 ```ruby
-get 'photos/:id', to: 'photos#show', defaults: { format: 'jpg' }
+defaults format: :json do
+  resources :photos
+end
 ```
 
-Rails would match `photos/12` to the `show` action of `PhotosController`, and set `params[:format]` to `"jpg"`.
-
 NOTE: You cannot override defaults via query parameters - this is for security reasons. The only defaults that can be overridden are dynamic segments via substitution in the URL path.
 
 ### Naming Routes
@@ -653,7 +640,7 @@ match 'photos', to: 'photos#show', via: :all
 
 NOTE: Routing both `GET` and `POST` requests to a single action has security implications. In general, you should avoid routing all verbs to an action unless you have a good reason to.
 
-NOTE: 'GET' in Rails won't check for CSRF token. You should never write to the database from 'GET' requests, for more information see the [security guide](security.html#csrf-countermeasures) on CSRF countermeasures.
+NOTE: `GET` in Rails won't check for CSRF token. You should never write to the database from `GET` requests, for more information see the [security guide](security.html#csrf-countermeasures) on CSRF countermeasures.
 
 ### Segment Constraints
 
@@ -821,14 +808,14 @@ NOTE: For the curious, `'articles#index'` actually expands out to `ArticlesContr
 
 If you specify a Rack application as the endpoint for a matcher, remember that
 the route will be unchanged in the receiving application. With the following
-route your Rack application should expect the route to be '/admin':
+route your Rack application should expect the route to be `/admin`:
 
 ```ruby
 match '/admin', to: AdminApp, via: :all
 ```
 
 If you would prefer to have your Rack application receive requests at the root
-path instead, use mount:
+path instead, use `mount`:
 
 ```ruby
 mount AdminApp, at: '/admin'
@@ -865,6 +852,49 @@ You can specify unicode character routes directly. For example:
 get 'こんにちは', to: 'welcome#index'
 ```
 
+### Direct routes
+
+You can create custom URL helpers directly. For example:
+
+```ruby
+direct :homepage do
+  "http://www.rubyonrails.org"
+end
+
+# >> homepage_url
+# => "http://www.rubyonrails.org"
+```
+
+The return value of the block must be a valid argument for the `url_for` method. So, you can pass a valid string URL, Hash, Array, an Active Model instance, or an Active Model class.
+
+```ruby
+direct :commentable do |model|
+  [ model, anchor: model.dom_id ]
+end
+
+direct :main do
+  { controller: 'pages', action: 'index', subdomain: 'www' }
+end
+```
+
+### Using `resolve`
+
+The `resolve` method allows customizing polymorphic mapping of models. For example:
+
+``` ruby
+resource :basket
+
+resolve("Basket") { [:basket] }
+```
+
+``` erb
+<%= form_for @basket do |form| %>
+  <!-- basket form -->
+<% end %>
+```
+
+This will generate the singular URL `/basket` instead of the usual `/baskets/:id`.
+
 Customizing Resourceful Routes
 ------------------------------
 
diff --git a/guides/source/ruby_on_rails_guides_guidelines.md b/guides/source/ruby_on_rails_guides_guidelines.md
index 50866350f8..de63e193f4 100644
--- a/guides/source/ruby_on_rails_guides_guidelines.md
+++ b/guides/source/ruby_on_rails_guides_guidelines.md
@@ -50,6 +50,48 @@ Use the same inline formatting as regular text:
 ##### The `:content_type` Option
 ```
 
+Linking to the API
+------------------
+
+Links to the API (`api.rubyonrails.org`) are processed by the guides generator in the following manner:
+
+Links that include a release tag are left untouched. For example
+
+```
+http://api.rubyonrails.org/v5.0.1/classes/ActiveRecord/Attributes/ClassMethods.html
+```
+
+is not modified.
+
+Please use these in release notes, since they should point to the corresponding version no matter the target being generated.
+
+If the link does not include a release tag and edge guides are being generated, the domain is replaced by `edgeapi.rubyonrails.org`. For example,
+
+```
+http://api.rubyonrails.org/classes/ActionDispatch/Response.html
+```
+
+becomes
+
+```
+http://edgeapi.rubyonrails.org/classes/ActionDispatch/Response.html
+```
+
+If the link does not include a release tag and release guides are being generated, the Rails version is injected. For example, if we are generating the guides for v5.1.0 the link
+
+```
+http://api.rubyonrails.org/classes/ActionDispatch/Response.html
+```
+
+becomes
+
+```
+http://api.rubyonrails.org/v5.1.0/classes/ActionDispatch/Response.html
+```
+
+Please don't link to `edgeapi.rubyonrails.org` manually.
+
+
 API Documentation Guidelines
 ----------------------------
 
@@ -97,8 +139,6 @@ By default, guides that have not been modified are not processed, so `ONLY` is r
 
 To force processing all the guides, pass `ALL=1`.
 
-It is also recommended that you work with `WARNINGS=1`. This detects duplicate IDs and warns about broken internal links.
-
 If you want to generate guides in a language other than English, you can keep them in a separate directory under `source` (eg. `source/es`) and use the `GUIDES_LANGUAGE` environment variable:
 
 ```
diff --git a/guides/source/security.md b/guides/source/security.md
index ca985134e6..916b1e32f8 100644
--- a/guides/source/security.md
+++ b/guides/source/security.md
@@ -1,7 +1,7 @@
 **DO NOT READ THIS FILE ON GITHUB, GUIDES ARE PUBLISHED ON http://guides.rubyonrails.org.**
 
-Ruby on Rails Security Guide
-============================
+Securing Rails Applications
+===========================
 
 This manual describes common security problems in web applications and how to avoid them with Rails.
 
@@ -52,7 +52,7 @@ User.find(session[:user_id])
 
 NOTE: _The session ID is a 32-character random hex string._
 
-The session ID is generated using `SecureRandom.hex` which generates a random hex string using platform specific methods (such as OpenSSL, /dev/urandom or Win32) for generating cryptographically secure random numbers. Currently it is not feasible to brute-force Rails' session IDs.
+The session ID is generated using `SecureRandom.hex` which generates a random hex string using platform specific methods (such as OpenSSL, /dev/urandom or Win32 CryptoAPI) for generating cryptographically secure random numbers. Currently it is not feasible to brute-force Rails' session IDs.
 
 ### Session Hijacking
 
@@ -85,39 +85,117 @@ This will also be a good idea, if you modify the structure of an object and old
 
 * _Critical data should not be stored in session_. If the user clears their cookies or closes the browser, they will be lost. And with a client-side session storage, the user can read the data.
 
-### Session Storage
+### Encrypted Session Storage
 
 NOTE: _Rails provides several storage mechanisms for the session hashes. The most important is `ActionDispatch::Session::CookieStore`._
 
-Rails 2 introduced a new default session storage, CookieStore. CookieStore saves the session hash directly in a cookie on the client-side. The server retrieves the session hash from the cookie and eliminates the need for a session ID. That will greatly increase the speed of the application, but it is a controversial storage option and you have to think about the security implications of it:
+The `CookieStore` saves the session hash directly in a cookie on the
+client-side. The server retrieves the session hash from the cookie and
+eliminates the need for a session ID. That will greatly increase the
+speed of the application, but it is a controversial storage option and
+you have to think about the security implications and storage
+limitations of it:
+
+* Cookies imply a strict size limit of 4kB. This is fine as you should
+  not store large amounts of data in a session anyway, as described
+  before. Storing the current user's database id in a session is common
+  practice.
+
+* Session cookies do not invalidate themselves and can be maliciously
+  reused. It may be a good idea to have your application invalidate old
+  session cookies using a stored timestamp.
+
+The `CookieStore` uses the
+[encrypted](http://api.rubyonrails.org/classes/ActionDispatch/Cookies/ChainedCookieJars.html#method-i-encrypted)
+cookie jar to provide a secure, encrypted location to store session
+data. Cookie-based sessions thus provide both integrity as well as
+confidentiality to their contents. The encryption key, as well as the
+verification key used for
+[signed](http://api.rubyonrails.org/classes/ActionDispatch/Cookies/ChainedCookieJars.html#method-i-signed)
+cookies, is derived from the `secret_key_base` configuration value.
+
+As of Rails 5.2 encrypted cookies and sessions are protected using AES
+GCM encryption. This form of encryption is a type of Authenticated
+Encryption and couples authentication and encryption in single step
+while also producing shorter ciphertexts as compared to other
+algorithms previously used. The key for cookies encrypted with AES GCM
+are derived using a salt value defined by the
+`config.action_dispatch.authenticated_encrypted_cookie_salt`
+configuration value.
+
+Prior to this version, encrypted cookies were secured using AES in CBC
+mode with HMAC using SHA1 for authentication. The keys for this type of
+encryption and for HMAC verification were derived via the salts defined
+by `config.action_dispatch.encrypted_cookie_salt` and
+`config.action_dispatch.encrypted_signed_cookie_salt` respectively.
+
+Prior to Rails version 4 in both versions 2 and 3, session cookies were
+protected using only HMAC verification. As such, these session cookies
+only provided integrity to their content because the actual session data
+was stored in plaintext encoded as base64. This is how `signed` cookies
+work in the current version of Rails. These kinds of cookies are still
+useful for protecting the integrity of certain client-stored data and
+information.
+
+__Do not use a trivial secret for the `secret_key_base`, i.e. a word
+from a dictionary, or one which is shorter than 30 characters! Instead
+use `rails secret` to generate secret keys!__
+
+It is also important to use different salt values for encrypted and
+signed cookies. Using the same value for different salt configuration
+values may lead to the same derived key being used for different
+security features which in turn may weaken the strength of the key.
+
+In test and development applications get a `secret_key_base` derived from the app name. Other environments must use a random key present in `config/credentials.yml.enc`, shown here in its decrypted state:
+
+    secret_key_base: 492f...
 
-* Cookies imply a strict size limit of 4kB. This is fine as you should not store large amounts of data in a session anyway, as described before. _Storing the current user's database id in a session is usually ok_.
+If you have received an application where the secret was exposed (e.g. an application whose source was shared), strongly consider changing the secret.
 
-* The client can see everything you store in a session, because it is stored in clear-text (actually Base64-encoded, so not encrypted). So, of course, _you don't want to store any secrets here_. To prevent session hash tampering, a digest is calculated from the session with a server-side secret (`secrets.secret_token`) and inserted into the end of the cookie.
+### Rotating Encrypted and Signed Cookies Configurations
 
-However, since Rails 4, the default store is EncryptedCookieStore. With
-EncryptedCookieStore the session is encrypted before being stored in a cookie.
-This prevents the user from accessing and tampering the content of the cookie.
-Thus the session becomes a more secure place to store data. The encryption is
-done using a server-side secret key `secrets.secret_key_base` stored in
-`config/secrets.yml`.
+Rotation is ideal for changing cookie configurations and ensuring old cookies
+aren't immediately invalid. Your users then have a chance to visit your site,
+get their cookie read with an old configuration and have it rewritten with the
+new change. The rotation can then be removed once you're comfortable enough
+users have had their chance to get their cookies upgraded.
 
-That means the security of this storage depends on this secret (and on the digest algorithm, which defaults to SHA1, for compatibility). So _don't use a trivial secret, i.e. a word from a dictionary, or one which is shorter than 30 characters, use `rails secret` instead_.
+It's possible to rotate the ciphers and digests used for encrypted and signed cookies.
 
-`secrets.secret_key_base` is used for specifying a key which allows sessions for the application to be verified against a known secure key to prevent tampering. Applications get `secrets.secret_key_base` initialized to a random key present in `config/secrets.yml`, e.g.:
+For instance to change the digest used for signed cookies from SHA1 to SHA256,
+you would first assign the new configuration value:
 
-    development:
-      secret_key_base: a75d...
+```ruby
+Rails.application.config.action_dispatch.signed_cookie_digest = "SHA256"
+```
 
-    test:
-      secret_key_base: 492f...
+Now add a rotation for the old SHA1 digest so existing cookies are
+seamlessly upgraded to the new SHA256 digest.
 
-    production:
-      secret_key_base: <%= ENV["SECRET_KEY_BASE"] %>
+```ruby
+Rails.application.config.action_dispatch.cookies_rotations.tap do |cookies|
+  cookies.rotate :signed, digest: "SHA1"
+end
+```
 
-Older versions of Rails use CookieStore, which uses `secret_token` instead of `secret_key_base` that is used by EncryptedCookieStore. Read the upgrade documentation for more information.
+Then any written signed cookies will be digested with SHA256. Old cookies
+that were written with SHA1 can still be read, and if accessed will be written
+with the new digest so they're upgraded and won't be invalid when you remove the
+rotation.
 
-If you have received an application where the secret was exposed (e.g. an application whose source was shared), strongly consider changing the secret.
+Once users with SHA1 digested signed cookies should no longer have a chance to
+have their cookies rewritten, remove the rotation.
+
+While you can setup as many rotations as you'd like it's not common to have many
+rotations going at any one time.
+
+For more details on key rotation with encrypted and signed messages as
+well as the various options the `rotate` method accepts, please refer to
+the
+[MessageEncryptor API](http://api.rubyonrails.org/classes/ActiveSupport/MessageEncryptor.html)
+and
+[MessageVerifier API](http://api.rubyonrails.org/classes/ActiveSupport/MessageVerifier.html)
+documentation.
 
 ### Replay Attacks for CookieStore Sessions
 
@@ -131,7 +209,7 @@ It works like this:
 * The user takes the cookie from the first step (which they previously copied) and replaces the current cookie in the browser.
 * The user has their original credit back.
 
-Including a nonce (a random value) in the session solves replay attacks. A nonce is valid only once, and the server has to keep track of all the valid nonces. It gets even more complicated if you have several application servers (mongrels). Storing nonces in a database table would defeat the entire purpose of CookieStore (avoiding accessing the database).
+Including a nonce (a random value) in the session solves replay attacks. A nonce is valid only once, and the server has to keep track of all the valid nonces. It gets even more complicated if you have several application servers. Storing nonces in a database table would defeat the entire purpose of CookieStore (avoiding accessing the database).
 
 The best _solution against it is not to store this kind of data in a session, but in the database_. In this case store the credit in the database and the logged_in_user_id in the session.
 
@@ -182,7 +260,7 @@ class Session < ApplicationRecord
 end
 ```
 
-The section about session fixation introduced the problem of maintained sessions. An attacker maintaining a session every five minutes can keep the session alive forever, although you are expiring sessions. A simple solution for this would be to add a created_at column to the sessions table. Now you can delete sessions that were created a long time ago. Use this line in the sweep method above:
+The section about session fixation introduced the problem of maintained sessions. An attacker maintaining a session every five minutes can keep the session alive forever, although you are expiring sessions. A simple solution for this would be to add a `created_at` column to the sessions table. Now you can delete sessions that were created a long time ago. Use this line in the sweep method above:
 
 ```ruby
 delete_all "updated_at < '#{time.ago.to_s(:db)}' OR
@@ -212,7 +290,7 @@ CSRF appears very rarely in CVE (Common Vulnerabilities and Exposures) - less th
 
 NOTE: _First, as is required by the W3C, use GET and POST appropriately. Secondly, a security token in non-GET requests will protect your application from CSRF._
 
-The HTTP protocol basically provides two main types of requests - GET and POST (and more, but they are not supported by most browsers). The World Wide Web Consortium (W3C) provides a checklist for choosing HTTP GET or POST:
+The HTTP protocol basically provides two main types of requests - GET and POST (DELETE, PUT, and PATCH should be used like POST). The World Wide Web Consortium (W3C) provides a checklist for choosing HTTP GET or POST:
 
 **Use GET if:**
 
@@ -224,7 +302,7 @@ The HTTP protocol basically provides two main types of requests - GET and POST (
 * The interaction _changes the state_ of the resource in a way that the user would perceive (e.g., a subscription to a service), or
 * The user is _held accountable for the results_ of the interaction.
 
-If your web application is RESTful, you might be used to additional HTTP verbs, such as PATCH, PUT or DELETE. Most of today's web browsers, however, do not support them - only GET and POST. Rails uses a hidden `_method` field to handle this barrier.
+If your web application is RESTful, you might be used to additional HTTP verbs, such as PATCH, PUT or DELETE. Some legacy web browsers, however, do not support them - only GET and POST. Rails uses a hidden `_method` field to handle these cases.
 
 _POST requests can be sent automatically, too_. In this example, the link www.harmless.com is shown as the destination in the browser's status bar. But it has actually dynamically created a new form that sends a POST request.
 
@@ -249,7 +327,7 @@ There are many other possibilities, like using a `<script>` tag to make a cross-
 
 Note: We can't distinguish a `<script>` tag's origin—whether it's a tag on your own site or on some other malicious site—so we must block all `<script>` across the board, even if it's actually a safe same-origin script served from your own site. In these cases, explicitly skip CSRF protection on actions that serve JavaScript meant for a `<script>` tag.
 
-To protect against all other forged requests, we introduce a _required security token_ that our site knows but other sites don't know. We include the security token in requests and verify it on the server. This is a one-liner in your application controller, and is the default for newly created rails applications:
+To protect against all other forged requests, we introduce a _required security token_ that our site knows but other sites don't know. We include the security token in requests and verify it on the server. This is a one-liner in your application controller, and is the default for newly created Rails applications:
 
 ```ruby
 protect_from_forgery with: :exception
@@ -257,13 +335,12 @@ protect_from_forgery with: :exception
 
 This will automatically include a security token in all forms and Ajax requests generated by Rails. If the security token doesn't match what was expected, an exception will be thrown.
 
-NOTE: By default, Rails includes jQuery and an [unobtrusive scripting adapter for
-jQuery](https://github.com/rails/jquery-ujs), which adds a header called
-`X-CSRF-Token` on every non-GET Ajax call made by jQuery with the security token.
-Without this header, non-GET Ajax requests won't be accepted by Rails. When using
-another library to make Ajax calls, it is necessary to add the security token as
-a default header for Ajax calls in your library. To get the token, have a look at
-`<meta name='csrf-token' content='THE-TOKEN'>` tag printed by
+NOTE: By default, Rails includes an [unobtrusive scripting adapter](https://github.com/rails/rails/blob/master/actionview/app/assets/javascripts),
+which adds a header called `X-CSRF-Token` with the security token on every non-GET
+Ajax call. Without this header, non-GET Ajax requests won't be accepted by Rails.
+When using another library to make Ajax calls, it is necessary to add the security
+token as a default header for Ajax calls in your library. To get the token, have
+a look at `<meta name='csrf-token' content='THE-TOKEN'>` tag printed by
 `<%= csrf_meta_tags %>` in your application view.
 
 It is common to use persistent cookies to store user information, with `cookies.permanent` for example. In this case, the cookies will not be cleared and the out of the box CSRF protection will not be effective. If you are using a different cookie store than the session for this information, you must handle what to do with it yourself:
@@ -287,7 +364,7 @@ Another class of security vulnerabilities surrounds the use of redirection and f
 
 WARNING: _Redirection in a web application is an underestimated cracker tool: Not only can the attacker forward the user to a trap web site, they may also create a self-contained attack._
 
-Whenever the user is allowed to pass (parts of) the URL for redirection, it is possibly vulnerable. The most obvious attack would be to redirect users to a fake web application which looks and feels exactly as the original one. This so-called phishing attack works by sending an unsuspicious link in an email to the users, injecting the link by XSS in the web application or putting the link into an external site. It is unsuspicious, because the link starts with the URL to the web application and the URL to the malicious site is hidden in the redirection parameter: http://www.example.com/site/redirect?to= www.attacker.com. Here is an example of a legacy action:
+Whenever the user is allowed to pass (parts of) the URL for redirection, it is possibly vulnerable. The most obvious attack would be to redirect users to a fake web application which looks and feels exactly as the original one. This so-called phishing attack works by sending an unsuspicious link in an email to the users, injecting the link by XSS in the web application or putting the link into an external site. It is unsuspicious, because the link starts with the URL to the web application and the URL to the malicious site is hidden in the redirection parameter: http://www.example.com/site/redirect?to=www.attacker.com. Here is an example of a legacy action:
 
 ```ruby
 def legacy
@@ -357,7 +434,7 @@ send_file('/var/www/uploads/' + params[:filename])
 Simply pass a file name like "../../../etc/passwd" to download the server's login information. A simple solution against this, is to _check that the requested file is in the expected directory_:
 
 ```ruby
-basename = File.expand_path(File.join(File.dirname(__FILE__), '../../files'))
+basename = File.expand_path('../../files', __dir__)
 filename = File.expand_path(File.join(basename, @file.public_filename))
 raise if basename !=
      File.expand_path(File.join(File.dirname(filename), '../../../'))
@@ -377,7 +454,7 @@ In 2007 there was the first tailor-made trojan which stole information from an I
 
 Having one single place in the admin interface or Intranet, where the input has not been sanitized, makes the entire application vulnerable. Possible exploits include stealing the privileged administrator's cookie, injecting an iframe to steal the administrator's password or installing malicious software through browser security holes to take over the administrator's computer.
 
-Refer to the Injection section for countermeasures against XSS. It is _recommended to use the SafeErb plugin_ also in an Intranet or administration interface.
+Refer to the Injection section for countermeasures against XSS.
 
 **CSRF** Cross-Site Request Forgery (CSRF), also known as Cross-Site Reference Forgery (XSRF), is a gigantic attack method, it allows the attacker to do everything the administrator or Intranet user may do. As you have already seen above how CSRF works, here are a few examples of what attackers can do in the Intranet or admin interface.
 
@@ -459,7 +536,7 @@ Depending on your web application, there may be more ways to hijack the user's a
 
 INFO: _A CAPTCHA is a challenge-response test to determine that the response is not generated by a computer. It is often used to protect registration forms from attackers and comment forms from automatic spam bots by asking the user to type the letters of a distorted image. This is the positive CAPTCHA, but there is also the negative CAPTCHA. The idea of a negative CAPTCHA is not for a user to prove that they are human, but reveal that a robot is a robot._
 
-A popular positive CAPTCHA API is [reCAPTCHA](http://recaptcha.net/) which displays two distorted images of words from old books. It also adds an angled line, rather than a distorted background and high levels of warping on the text as earlier CAPTCHAs did, because the latter were broken. As a bonus, using reCAPTCHA helps to digitize old books. [ReCAPTCHA](https://github.com/ambethia/recaptcha/) is also a Rails plug-in with the same name as the API.
+A popular positive CAPTCHA API is [reCAPTCHA](https://developers.google.com/recaptcha/) which displays two distorted images of words from old books. It also adds an angled line, rather than a distorted background and high levels of warping on the text as earlier CAPTCHAs did, because the latter were broken. As a bonus, using reCAPTCHA helps to digitize old books. [ReCAPTCHA](https://github.com/ambethia/recaptcha/) is also a Rails plug-in with the same name as the API.
 
 You will get two keys from the API, a public and a private key, which you have to put into your Rails environment. After that you can use the recaptcha_tags method in the view, and the verify_recaptcha method in the controller. Verify_recaptcha will return false if the validation fails.
 The problem with CAPTCHAs is that they have a negative impact on the user experience. Additionally, some visually impaired users have found certain kinds of distorted CAPTCHAs difficult to read. Still, positive CAPTCHAs are one of the best methods to prevent all kinds of bots from submitting forms.
@@ -615,7 +692,7 @@ The two dashes start a comment ignoring everything after it. So the query return
 Usually a web application includes access control. The user enters their login credentials and the web application tries to find the matching record in the users table. The application grants access when it finds a record. However, an attacker may possibly bypass this check with SQL injection. The following shows a typical database query in Rails to find the first record in the users table which matches the login credentials parameters supplied by the user.
 
 ```ruby
-User.first("login = '#{params[:name]}' AND password = '#{params[:password]}'")
+User.find_by("login = '#{params[:name]}' AND password = '#{params[:password]}'")
 ```
 
 If an attacker enters ' OR '1'='1 as the name, and ' OR '2'>'1 as the password, the resulting SQL query will be:
@@ -681,7 +758,7 @@ The most common entry points are message posts, user comments, and guest books,
 
 XSS attacks work like this: An attacker injects some code, the web application saves it and displays it on a page, later presented to a victim. Most XSS examples simply display an alert box, but it is more powerful than that. XSS can steal the cookie, hijack the session, redirect the victim to a fake website, display advertisements for the benefit of the attacker, change elements on the web site to get confidential information or install malicious software through security holes in the web browser.
 
-During the second half of 2007, there were 88 vulnerabilities reported in Mozilla browsers, 22 in Safari, 18 in IE, and 12 in Opera. The [Symantec Global Internet Security threat report](http://eval.symantec.com/mktginfo/enterprise/white_papers/b-whitepaper_internet_security_threat_report_xiii_04-2008.en-us.pdf) also documented 239 browser plug-in vulnerabilities in the last six months of 2007. [Mpack](http://pandalabs.pandasecurity.com/mpack-uncovered/) is a very active and up-to-date attack framework which exploits these vulnerabilities. For criminal hackers, it is very attractive to exploit an SQL-Injection vulnerability in a web application framework and insert malicious code in every textual table column. In April 2008 more than 510,000 sites were hacked like this, among them the British government, United Nations, and many more high targets.
+During the second half of 2007, there were 88 vulnerabilities reported in Mozilla browsers, 22 in Safari, 18 in IE, and 12 in Opera. The [Symantec Global Internet Security threat report](http://eval.symantec.com/mktginfo/enterprise/white_papers/b-whitepaper_internet_security_threat_report_xiii_04-2008.en-us.pdf) also documented 239 browser plug-in vulnerabilities in the last six months of 2007. [Mpack](http://pandalabs.pandasecurity.com/mpack-uncovered/) is a very active and up-to-date attack framework which exploits these vulnerabilities. For criminal hackers, it is very attractive to exploit an SQL-Injection vulnerability in a web application framework and insert malicious code in every textual table column. In April 2008 more than 510,000 sites were hacked like this, among them the British government, United Nations, and many more high profile targets.
 
 #### HTML/JavaScript Injection
 
@@ -762,7 +839,7 @@ s = sanitize(user_input, tags: tags, attributes: %w(href title))
 
 This allows only the given tags and does a good job, even against all kinds of tricks and malformed tags.
 
-As a second step, _it is good practice to escape all output of the application_, especially when re-displaying user input, which hasn't been input-filtered (as in the search form example earlier on). _Use `escapeHTML()` (or its alias `h()`) method_ to replace the HTML input characters &amp;, &quot;, &lt;, and &gt; by their uninterpreted representations in HTML (`&amp;`, `&quot;`, `&lt;`, and `&gt;`). However, it can easily happen that the programmer forgets to use it, so _it is recommended to use the SafeErb gem. SafeErb reminds you to escape strings from external sources.
+As a second step, _it is good practice to escape all output of the application_, especially when re-displaying user input, which hasn't been input-filtered (as in the search form example earlier on). _Use `escapeHTML()` (or its alias `h()`) method_ to replace the HTML input characters &amp;, &quot;, &lt;, and &gt; by their uninterpreted representations in HTML (`&amp;`, `&quot;`, `&lt;`, and `&gt;`).
 
 ##### Obfuscation and Encoding Injection
 
@@ -797,7 +874,7 @@ In December 2006, 34,000 actual user names and passwords were stolen in a [MySpa
 
 INFO: _CSS Injection is actually JavaScript injection, because some browsers (IE, some versions of Safari and others) allow JavaScript in CSS. Think twice about allowing custom CSS in your web application._
 
-CSS Injection is explained best by the well-known [MySpace Samy worm](http://namb.la/popular/tech.html). This worm automatically sent a friend request to Samy (the attacker) simply by visiting his profile. Within several hours he had over 1 million friend requests, which created so much traffic that MySpace went offline. The following is a technical explanation of that worm.
+CSS Injection is explained best by the well-known [MySpace Samy worm](https://samy.pl/popular/tech.html). This worm automatically sent a friend request to Samy (the attacker) simply by visiting his profile. Within several hours he had over 1 million friend requests, which created so much traffic that MySpace went offline. The following is a technical explanation of that worm.
 
 MySpace blocked many tags, but allowed CSS. So the worm's author put JavaScript into CSS like this:
 
@@ -965,7 +1042,7 @@ When `params[:token]` is one of: `[nil]`, `[nil, nil, ...]` or
 `['foo', nil]` it will bypass the test for `nil`, but `IS NULL` or
 `IN ('foo', NULL)` where clauses still will be added to the SQL query.
 
-To keep rails secure by default, `deep_munge` replaces some of the values with
+To keep Rails secure by default, `deep_munge` replaces some of the values with
 `nil`. Below table shows what the parameters look like based on `JSON` sent in
 request:
 
@@ -1019,34 +1096,40 @@ Here is a list of common headers:
 * **X-Content-Type-Options:** _'nosniff' in Rails by default_ - stops the browser from guessing the MIME type of a file.
 * **X-Content-Security-Policy:** [A powerful mechanism for controlling which sites certain content types can be loaded from](http://w3c.github.io/webappsec/specs/content-security-policy/csp-specification.dev.html)
 * **Access-Control-Allow-Origin:** Used to control which sites are allowed to bypass same origin policies and send cross-origin requests.
-* **Strict-Transport-Security:** [Used to control if the browser is allowed to only access a site over a secure connection](http://en.wikipedia.org/wiki/HTTP_Strict_Transport_Security)
+* **Strict-Transport-Security:** [Used to control if the browser is allowed to only access a site over a secure connection](https://en.wikipedia.org/wiki/HTTP_Strict_Transport_Security)
 
 Environmental Security
 ----------------------
 
 It is beyond the scope of this guide to inform you on how to secure your application code and environments. However, please secure your database configuration, e.g. `config/database.yml`, and your server-side secret, e.g. stored in `config/secrets.yml`. You may want to further restrict access, using environment-specific versions of these files and any others that may contain sensitive information.
 
-### Custom secrets
+### Custom credentials
+
+Rails generates a `config/credentials.yml.enc` to store third-party credentials
+within the repo. This is only viable because Rails encrypts the file with a master
+key that's generated into a version control ignored `config/master.key` — Rails
+will also look for that key in `ENV["RAILS_MASTER_KEY"]`. Rails also requires the
+key to boot in production, so the credentials can be read.
+
+To edit stored credentials use `bin/rails credentials:edit`.
 
-Rails generates a `config/secrets.yml`. By default, this file contains the
-application's `secret_key_base`, but it could also be used to store other
-secrets such as access keys for external APIs.
+By default, this file contains the application's
+`secret_key_base`, but it could also be used to store other credentials such as
+access keys for external APIs.
 
-The secrets added to this file are accessible via `Rails.application.secrets`.
-For example, with the following `config/secrets.yml`:
+The credentials added to this file are accessible via `Rails.application.credentials`.
+For example, with the following decrypted `config/credentials.yml.enc`:
 
-    development:
-      secret_key_base: 3b7cd727ee24e8444053437c36cc66c3
-      some_api_key: SOMEKEY
+    secret_key_base: 3b7cd727ee24e8444053437c36cc66c3
+    some_api_key: SOMEKEY
 
-`Rails.application.secrets.some_api_key` returns `SOMEKEY` in the development
-environment.
+`Rails.application.credentials.some_api_key` returns `SOMEKEY` in any environment.
 
 If you want an exception to be raised when some key is blank, use the bang
 version:
 
 ```ruby
-Rails.application.secrets.some_api_key! # => raises KeyError: key not found: :some_api_key
+Rails.application.credentials.some_api_key! # => raises KeyError: :some_api_key is blank
 ```
 
 Additional Resources
@@ -1054,6 +1137,7 @@ Additional Resources
 
 The security landscape shifts and it is important to keep up to date, because missing a new vulnerability can be catastrophic. You can find additional resources about (Rails) security here:
 
-* Subscribe to the Rails security [mailing list](http://groups.google.com/group/rubyonrails-security)
-* [Keep up to date on the other application layers](http://secunia.com/) (they have a weekly newsletter, too)
-* A [good security blog](https://www.owasp.org) including the [Cross-Site scripting Cheat Sheet](https://www.owasp.org/index.php/DOM_based_XSS_Prevention_Cheat_Sheet)
+* Subscribe to the Rails security [mailing list](https://groups.google.com/forum/#!forum/rubyonrails-security).
+* [Brakeman - Rails Security Scanner](https://brakemanscanner.org/) - To perform static security analysis for Rails applications.
+* [Keep up to date on the other application layers](http://secunia.com/) (they have a weekly newsletter, too).
+* A [good security blog](https://www.owasp.org) including the [Cross-Site scripting Cheat Sheet](https://www.owasp.org/index.php/DOM_based_XSS_Prevention_Cheat_Sheet).
diff --git a/guides/source/testing.md b/guides/source/testing.md
index 924a8a09f5..bf310cf2db 100644
--- a/guides/source/testing.md
+++ b/guides/source/testing.md
@@ -1,14 +1,14 @@
 **DO NOT READ THIS FILE ON GITHUB, GUIDES ARE PUBLISHED ON http://guides.rubyonrails.org.**
 
-A Guide to Testing Rails Applications
-=====================================
+Testing Rails Applications
+==========================
 
 This guide covers built-in mechanisms in Rails for testing your application.
 
 After reading this guide, you will know:
 
 * Rails testing terminology.
-* How to write unit, functional, and integration tests for your application.
+* How to write unit, functional, integration, and system tests for your application.
 * Other popular testing approaches and plugins.
 
 --------------------------------------------------------------------------------
@@ -18,7 +18,7 @@ Why Write Tests for your Rails Applications?
 
 Rails makes it super easy to write your tests. It starts by producing skeleton test code while you are creating your models and controllers.
 
-By simply running your Rails tests you can ensure your code adheres to the desired functionality even after some major code refactoring.
+By running your Rails tests you can ensure your code adheres to the desired functionality even after some major code refactoring.
 
 Rails tests can also simulate browser requests and thus you can test your application's response without having to test it through your browser.
 
@@ -33,16 +33,27 @@ Rails creates a `test` directory for you as soon as you create a Rails project u
 
 ```bash
 $ ls -F test
-controllers/    helpers/        mailers/        test_helper.rb
-fixtures/       integration/    models/
+controllers/           helpers/               mailers/               system/                test_helper.rb
+fixtures/              integration/           models/                application_system_test_case.rb
 ```
 
-The `models` directory is meant to hold tests for your models, the `controllers` directory is meant to hold tests for your controllers and the `integration` directory is meant to hold tests that involve any number of controllers interacting. There is also a directory for testing your mailers and one for testing view helpers.
+The `helpers`, `mailers`, and `models` directories are meant to hold tests for view helpers, mailers, and models, respectively. The `controllers` directory is meant to hold tests for controllers, routes, and views. The `integration` directory is meant to hold tests for interactions between controllers.
+
+The system test directory holds system tests, which are used for full browser
+testing of your application. System tests allow you to test your application
+the way your users experience it and help you test your JavaScript as well.
+System tests inherit from Capybara and perform in browser tests for your
+application.
 
 Fixtures are a way of organizing test data; they reside in the `fixtures` directory.
 
+A `jobs` directory will also be created when an associated test is first generated.
+
 The `test_helper.rb` file holds the default configuration for your tests.
 
+The `application_system_test_case.rb` holds the default configuration for your system
+tests.
+
 
 ### The Test Environment
 
@@ -112,7 +123,7 @@ def test_the_truth
 end
 ```
 
-However only the `test` macro allows a more readable test name. You can still use regular method definitions though.
+Although you can still use regular method definitions, using the `test` macro allows for a more readable test name.
 
 NOTE: The method name is generated by replacing spaces with underscores. The result does not need to be a valid Ruby identifier though, the name may contain punctuation characters etc. That's because in Ruby technically any string may be a method name. This may require use of `define_method` and `send` calls to function properly, but formally there's little restriction on the name.
 
@@ -146,18 +157,28 @@ Let us run this newly added test (where `6` is the number of line where the test
 
 ```bash
 $ bin/rails test test/models/article_test.rb:6
+Run options: --seed 44656
+
+# Running:
+
 F
 
-Finished tests in 0.044632s, 22.4054 tests/s, 22.4054 assertions/s.
+Failure:
+ArticleTest#test_should_not_save_article_without_title [/path/to/blog/test/models/article_test.rb:6]:
+Expected true to be nil or false
+
+
+bin/rails test test/models/article_test.rb:6
+
 
-  1) Failure:
-test_should_not_save_article_without_title(ArticleTest) [test/models/article_test.rb:6]:
-Failed assertion, no message given.
 
-1 tests, 1 assertions, 1 failures, 0 errors, 0 skips
+Finished in 0.023918s, 41.8090 runs/s, 41.8090 assertions/s.
+
+1 runs, 1 assertions, 1 failures, 0 errors, 0 skips
+
 ```
 
-In the output, `F` denotes a failure. You can see the corresponding trace shown under `1)` along with the name of the failing test. The next few lines contain the stack trace followed by a message that mentions the actual value and the expected value by the assertion. The default assertion messages provide just enough information to help pinpoint the error. To make the assertion failure message more readable, every assertion provides an optional message parameter, as shown here:
+In the output, `F` denotes a failure. You can see the corresponding trace shown under `Failure` along with the name of the failing test. The next few lines contain the stack trace followed by a message that mentions the actual value and the expected value by the assertion. The default assertion messages provide just enough information to help pinpoint the error. To make the assertion failure message more readable, every assertion provides an optional message parameter, as shown here:
 
 ```ruby
 test "should not save article without title" do
@@ -169,8 +190,8 @@ end
 Running this test shows the friendlier assertion message:
 
 ```bash
-  1) Failure:
-test_should_not_save_article_without_title(ArticleTest) [test/models/article_test.rb:6]:
+Failure:
+ArticleTest#test_should_not_save_article_without_title [/path/to/blog/test/models/article_test.rb:6]:
 Saved the article without a title
 ```
 
@@ -186,11 +207,15 @@ Now the test should pass. Let us verify by running the test again:
 
 ```bash
 $ bin/rails test test/models/article_test.rb:6
+Run options: --seed 31252
+
+# Running:
+
 .
 
-Finished tests in 0.047721s, 20.9551 tests/s, 20.9551 assertions/s.
+Finished in 0.027476s, 36.3952 runs/s, 36.3952 assertions/s.
 
-1 tests, 1 assertions, 0 failures, 0 errors, 0 skips
+1 runs, 1 assertions, 0 failures, 0 errors, 0 skips
 ```
 
 Now, if you noticed, we first wrote a test which fails for a desired
@@ -215,16 +240,25 @@ Now you can see even more output in the console from running the tests:
 
 ```bash
 $ bin/rails test test/models/article_test.rb
-E
+Run options: --seed 1808
+
+# Running:
 
-Finished tests in 0.030974s, 32.2851 tests/s, 0.0000 assertions/s.
+.E
 
-  1) Error:
-test_should_report_error(ArticleTest):
-NameError: undefined local variable or method `some_undefined_variable' for #<ArticleTest:0x007fe32e24afe0>
-    test/models/article_test.rb:10:in `block in <class:ArticleTest>'
+Error:
+ArticleTest#test_should_report_error:
+NameError: undefined local variable or method 'some_undefined_variable' for #<ArticleTest:0x007fee3aa71798>
+    test/models/article_test.rb:11:in 'block in <class:ArticleTest>'
 
-1 tests, 0 assertions, 0 failures, 1 errors, 0 skips
+
+bin/rails test test/models/article_test.rb:9
+
+
+
+Finished in 0.040609s, 49.2500 runs/s, 24.6250 assertions/s.
+
+2 runs, 1 assertions, 0 failures, 1 errors, 0 skips
 ```
 
 Notice the 'E' in the output. It denotes a test with error.
@@ -239,7 +273,7 @@ When a test fails you are presented with the corresponding backtrace. By default
 Rails filters that backtrace and will only print lines relevant to your
 application. This eliminates the framework noise and helps to focus on your
 code. However there are situations when you want to see the full
-backtrace. Simply set the `-b` (or `--backtrace`) argument to enable this behavior:
+backtrace. Set the `-b` (or `--backtrace`) argument to enable this behavior:
 
 ```bash
 $ bin/rails test -b test/models/article_test.rb
@@ -285,9 +319,10 @@ specify to make your test failure messages clearer.
 | `assert_not_includes( collection, obj, [msg] )`                  | Ensures that `obj` is not in `collection`.|
 | `assert_in_delta( expected, actual, [delta], [msg] )`            | Ensures that the numbers `expected` and `actual` are within `delta` of each other.|
 | `assert_not_in_delta( expected, actual, [delta], [msg] )`        | Ensures that the numbers `expected` and `actual` are not within `delta` of each other.|
+| `assert_in_epsilon ( expected, actual, [epsilon], [msg] )`       | Ensures that the numbers `expected` and `actual` have a relative error less than `epsilon`.|
+| `assert_not_in_epsilon ( expected, actual, [epsilon], [msg] )`   | Ensures that the numbers `expected` and `actual` don't have a relative error less than `epsilon`.|
 | `assert_throws( symbol, [msg] ) { block }`                       | Ensures that the given block throws the symbol.|
 | `assert_raises( exception1, exception2, ... ) { block }`         | Ensures that the given block raises one of the given exceptions.|
-| `assert_nothing_raised { block }`                                | Ensures that the given block doesn't raise any exceptions.|
 | `assert_instance_of( class, obj, [msg] )`                        | Ensures that `obj` is an instance of `class`.|
 | `assert_not_instance_of( class, obj, [msg] )`                    | Ensures that `obj` is not an instance of `class`.|
 | `assert_kind_of( class, obj, [msg] )`                            | Ensures that `obj` is an instance of `class` or is descending from it.|
@@ -298,7 +333,6 @@ specify to make your test failure messages clearer.
 | `assert_not_operator( obj1, operator, [obj2], [msg] )`           | Ensures that `obj1.operator(obj2)` is false.|
 | `assert_predicate ( obj, predicate, [msg] )`                     | Ensures that `obj.predicate` is true, e.g. `assert_predicate str, :empty?`|
 | `assert_not_predicate ( obj, predicate, [msg] )`                 | Ensures that `obj.predicate` is false, e.g. `assert_not_predicate str, :empty?`|
-| `assert_send( array, [msg] )`                                    | Ensures that executing the method listed in `array[1]` on the object in `array[0]` with the parameters of `array[2 and up]` is true, e.g. assert_send [@user, :full_name, 'Sam Smith']. This one is weird eh?|
 | `flunk( [msg] )`                                                 | Ensures failure. This is useful to explicitly mark a test that isn't finished yet.|
 
 The above are a subset of assertions that minitest supports. For an exhaustive &
@@ -318,6 +352,9 @@ Rails adds some custom assertions of its own to the `minitest` framework:
 | --------------------------------------------------------------------------------- | ------- |
 | [`assert_difference(expressions, difference = 1, message = nil) {...}`](http://api.rubyonrails.org/classes/ActiveSupport/Testing/Assertions.html#method-i-assert_difference) | Test numeric difference between the return value of an expression as a result of what is evaluated in the yielded block.|
 | [`assert_no_difference(expressions, message = nil, &block)`](http://api.rubyonrails.org/classes/ActiveSupport/Testing/Assertions.html#method-i-assert_no_difference) | Asserts that the numeric result of evaluating an expression is not changed before and after invoking the passed in block.|
+| [`assert_changes(expressions, message = nil, from:, to:, &block)`](http://api.rubyonrails.org/classes/ActiveSupport/Testing/Assertions.html#method-i-assert_changes) | Test that the result of evaluating an expression is changed after invoking the passed in block.|
+| [`assert_no_changes(expressions, message = nil, &block)`](http://api.rubyonrails.org/classes/ActiveSupport/Testing/Assertions.html#method-i-assert_no_changes) | Test the result of evaluating an expression is not changed after invoking the passed in block.|
+| [`assert_nothing_raised { block }`](http://api.rubyonrails.org/classes/ActiveSupport/Testing/Assertions.html#method-i-assert_nothing_raised) | Ensures that the given block doesn't raise any exceptions.|
 | [`assert_recognizes(expected_options, path, extras={}, message=nil)`](http://api.rubyonrails.org/classes/ActionDispatch/Assertions/RoutingAssertions.html#method-i-assert_recognizes) | Asserts that the routing of the given path was handled correctly and that the parsed options (given in the expected_options hash) match path. Basically, it asserts that Rails recognizes the route given by expected_options.|
 | [`assert_generates(expected_path, options, defaults={}, extras = {}, message=nil)`](http://api.rubyonrails.org/classes/ActionDispatch/Assertions/RoutingAssertions.html#method-i-assert_generates) | Asserts that the provided options can be used to generate the provided path. This is the inverse of assert_recognizes. The extras parameter is used to tell the request the names and values of additional request parameters that would be in a query string. The message parameter allows you to specify a custom error message for assertion failures.|
 | [`assert_response(type, message = nil)`](http://api.rubyonrails.org/classes/ActionDispatch/Assertions/ResponseAssertions.html#method-i-assert_response) | Asserts that the response comes with a specific status code. You can specify `:success` to indicate 200-299, `:redirect` to indicate 300-399, `:missing` to indicate 404, or `:error` to match the 500-599 range. You can also pass an explicit status number or its symbolic equivalent. For more information, see [full list of status codes](http://rubydoc.info/github/rack/rack/master/Rack/Utils#HTTP_STATUS_CODES-constant) and how their [mapping](http://rubydoc.info/github/rack/rack/master/Rack/Utils#SYMBOL_TO_STATUS_CODE-constant) works.|
@@ -332,8 +369,10 @@ All the basic assertions such as `assert_equal` defined in `Minitest::Assertions
 * [`ActiveSupport::TestCase`](http://api.rubyonrails.org/classes/ActiveSupport/TestCase.html)
 * [`ActionMailer::TestCase`](http://api.rubyonrails.org/classes/ActionMailer/TestCase.html)
 * [`ActionView::TestCase`](http://api.rubyonrails.org/classes/ActionView/TestCase.html)
-* [`ActionDispatch::IntegrationTest`](http://api.rubyonrails.org/classes/ActionDispatch/IntegrationTest.html)
 * [`ActiveJob::TestCase`](http://api.rubyonrails.org/classes/ActiveJob/TestCase.html)
+* [`ActionDispatch::IntegrationTest`](http://api.rubyonrails.org/classes/ActionDispatch/IntegrationTest.html)
+* [`ActionDispatch::SystemTestCase`](http://api.rubyonrails.org/classes/ActionDispatch/SystemTestCase.html)
+* [`Rails::Generators::TestCase`](http://api.rubyonrails.org/classes/Rails/Generators/TestCase.html)
 
 Each of these classes include `Minitest::Assertions`, allowing us to use all of the basic assertions in our tests.
 
@@ -342,17 +381,21 @@ documentation](http://docs.seattlerb.org/minitest).
 
 ### The Rails Test Runner
 
-We can run all of our tests at once by using the `rails test` command.
+We can run all of our tests at once by using the `bin/rails test` command.
 
-Or we can run a single test by passing the `rails test` command the filename containing the test cases.
+Or we can run a single test file by passing the `bin/rails test` command the filename containing the test cases.
 
 ```bash
 $ bin/rails test test/models/article_test.rb
-.
+Run options: --seed 1559
 
-Finished tests in 0.009262s, 107.9680 tests/s, 107.9680 assertions/s.
+# Running:
 
-1 tests, 1 assertions, 0 failures, 0 errors, 0 skips
+..
+
+Finished in 0.027034s, 73.9810 runs/s, 110.9715 assertions/s.
+
+2 runs, 3 assertions, 0 failures, 0 errors, 0 skips
 ```
 
 This will run all test methods from the test case.
@@ -362,6 +405,10 @@ You can also run a particular test method from the test case by providing the
 
 ```bash
 $ bin/rails test test/models/article_test.rb -n test_the_truth
+Run options: -n test_the_truth --seed 43583
+
+# Running:
+
 .
 
 Finished tests in 0.009064s, 110.3266 tests/s, 110.3266 assertions/s.
@@ -372,7 +419,7 @@ Finished tests in 0.009064s, 110.3266 tests/s, 110.3266 assertions/s.
 You can also run a test at a specific line by providing the line number.
 
 ```bash
-$ bin/rails test test/models/post_test.rb:44 # run specific test and line
+$ bin/rails test test/models/article_test.rb:6 # run specific test and line
 ```
 
 You can also run an entire directory of tests by providing the path to the directory.
@@ -381,6 +428,39 @@ You can also run an entire directory of tests by providing the path to the direc
 $ bin/rails test test/controllers # run all tests from specific directory
 ```
 
+The test runner also provides a lot of other features like failing fast, deferring test output
+at the end of test run and so on. Check the documentation of the test runner as follows:
+
+```bash
+$ bin/rails test -h
+minitest options:
+    -h, --help                       Display this help.
+    -s, --seed SEED                  Sets random seed. Also via env. Eg: SEED=n rake
+    -v, --verbose                    Verbose. Show progress processing files.
+    -n, --name PATTERN               Filter run on /regexp/ or string.
+        --exclude PATTERN            Exclude /regexp/ or string from run.
+
+Known extensions: rails, pride
+
+Usage: bin/rails test [options] [files or directories]
+You can run a single test by appending a line number to a filename:
+
+    bin/rails test test/models/user_test.rb:27
+
+You can run multiple files and directories at the same time:
+
+    bin/rails test test/controllers test/integration/login_test.rb
+
+By default test failures and errors are reported inline during a run.
+
+Rails options:
+    -w, --warnings                   Run with Ruby warnings enabled
+    -e, --environment                Run tests in the ENV environment
+    -b, --backtrace                  Show the complete backtrace
+    -d, --defer-output               Output test failures and errors after the test run
+    -f, --fail-fast                  Abort test run on first failure or error
+    -c, --[no-]color                 Enable color in the output
+```
 
 The Test Database
 -----------------
@@ -440,7 +520,7 @@ steve:
 
 Each fixture is given a name followed by an indented list of colon-separated key/value pairs. Records are typically separated by a blank line. You can place comments in a fixture file by using the # character in the first column.
 
-If you are working with [associations](/association_basics.html), you can simply
+If you are working with [associations](/association_basics.html), you can
 define a reference node between two different fixtures. Here's an example with
 a `belongs_to`/`has_many` association:
 
@@ -523,13 +603,199 @@ create  test/fixtures/articles.yml
 
 Model tests don't have their own superclass like `ActionMailer::TestCase` instead they inherit from [`ActiveSupport::TestCase`](http://api.rubyonrails.org/classes/ActiveSupport/TestCase.html).
 
+System Testing
+--------------
+
+System tests allow you to test user interactions with your application, running tests
+in either a real or a headless browser. System tests uses Capybara under the hood.
+
+For creating Rails system tests, you use the `test/system` directory in your
+application. Rails provides a generator to create a system test skeleton for you.
+
+```bash
+$ bin/rails generate system_test users
+      invoke test_unit
+      create test/system/users_test.rb
+```
+
+Here's what a freshly generated system test looks like:
+
+```ruby
+require "application_system_test_case"
+
+class UsersTest < ApplicationSystemTestCase
+  # test "visiting the index" do
+  #   visit users_url
+  #
+  #   assert_selector "h1", text: "Users"
+  # end
+end
+```
+
+By default, system tests are run with the Selenium driver, using the Chrome
+browser, and a screen size of 1400x1400. The next section explains how to
+change the default settings.
+
+### Changing the default settings
+
+Rails makes changing the default settings for system tests very simple. All
+the setup is abstracted away so you can focus on writing your tests.
+
+When you generate a new application or scaffold, an `application_system_test_case.rb` file
+is created in the test directory. This is where all the configuration for your
+system tests should live.
+
+If you want to change the default settings you can change what the system
+tests are "driven by". Say you want to change the driver from Selenium to
+Poltergeist. First add the `poltergeist` gem to your `Gemfile`. Then in your
+`application_system_test_case.rb` file do the following:
+
+```ruby
+require "test_helper"
+require "capybara/poltergeist"
+
+class ApplicationSystemTestCase < ActionDispatch::SystemTestCase
+  driven_by :poltergeist
+end
+```
+
+The driver name is a required argument for `driven_by`. The optional arguments
+that can be passed to `driven_by` are `:using` for the browser (this will only
+be used by Selenium), `:screen_size` to change the size of the screen for
+screenshots, and `:options` which can be used to set options supported by the
+driver.
+
+```ruby
+require "test_helper"
+
+class ApplicationSystemTestCase < ActionDispatch::SystemTestCase
+  driven_by :selenium, using: :firefox
+end
+```
+
+If you want to use a headless browser, you could use Headless Chrome or Headless Firefox by adding
+`headless_chrome` or `headless_firefox` in the `:using` argument.
+
+```ruby
+require "test_helper"
+
+class ApplicationSystemTestCase < ActionDispatch::SystemTestCase
+  driven_by :selenium, using: :headless_chrome
+end
+```
+
+If your Capybara configuration requires more setup than provided by Rails, this
+additional configuration could be added into the `application_system_test_case.rb`
+file.
+
+Please see [Capybara's documentation](https://github.com/teamcapybara/capybara#setup)
+for additional settings.
+
+### Screenshot Helper
+
+The `ScreenshotHelper` is a helper designed to capture screenshots of your tests.
+This can be helpful for viewing the browser at the point a test failed, or
+to view screenshots later for debugging.
+
+Two methods are provided: `take_screenshot` and `take_failed_screenshot`.
+`take_failed_screenshot` is automatically included in `after_teardown` inside
+Rails.
+
+The `take_screenshot` helper method can be included anywhere in your tests to
+take a screenshot of the browser.
+
+### Implementing a system test
+
+Now we're going to add a system test to our blog application. We'll demonstrate
+writing a system test by visiting the index page and creating a new blog article.
+
+If you used the scaffold generator, a system test skeleton was automatically
+created for you. If you didn't use the scaffold generator, start by creating a
+system test skeleton.
+
+```bash
+$ bin/rails generate system_test articles
+```
+
+It should have created a test file placeholder for us. With the output of the
+previous command you should see:
+
+```bash
+      invoke  test_unit
+      create    test/system/articles_test.rb
+```
+
+Now let's open that file and write our first assertion:
+
+```ruby
+require "application_system_test_case"
+
+class ArticlesTest < ApplicationSystemTestCase
+  test "viewing the index" do
+    visit articles_path
+    assert_selector "h1", text: "Articles"
+  end
+end
+```
+
+The test should see that there is an `h1` on the articles index page and pass.
+
+Run the system tests.
+
+```bash
+bin/rails test:system
+```
+
+NOTE: By default, running `bin/rails test` won't run your system tests.
+Make sure to run `bin/rails test:system` to actually run them.
+
+#### Creating articles system test
+
+Now let's test the flow for creating a new article in our blog.
+
+```ruby
+test "creating an article" do
+  visit articles_path
+
+  click_on "New Article"
+
+  fill_in "Title", with: "Creating an Article"
+  fill_in "Body", with: "Created this article successfully!"
+
+  click_on "Create Article"
+
+  assert_text "Creating an Article"
+end
+```
+
+The first step is to call `visit articles_path`. This will take the test to the
+articles index page.
+
+Then the `click_on "New Article"` will find the "New Article" button on the
+index page. This will redirect the browser to `/articles/new`.
+
+Then the test will fill in the title and body of the article with the specified
+text. Once the fields are filled in, "Create Article" is clicked on which will
+send a POST request to create the new article in the database.
+
+We will be redirected back to the the articles index page and there we assert
+that the text from the new article's title is on the articles index page.
+
+#### Taking it further
+
+The beauty of system testing is that it is similar to integration testing in
+that it tests the user's interaction with your controller, model, and view, but
+system testing is much more robust and actually tests your application as if
+a real user were using it. Going forward, you can test anything that the user
+themselves would do in your application such as commenting, deleting articles,
+publishing draft articles, etc.
 
 Integration Testing
 -------------------
 
 Integration tests are used to test how various parts of your application interact. They are generally used to test important workflows within our application.
 
-For creating Rails integration tests, we use the 'test/integration' directory for our application. Rails provides a generator to create an integration test skeleton for us.
+For creating Rails integration tests, we use the `test/integration` directory for our application. Rails provides a generator to create an integration test skeleton for us.
 
 ```bash
 $ bin/rails generate integration_test user_flows
@@ -537,7 +803,7 @@ $ bin/rails generate integration_test user_flows
       create  test/integration/user_flows_test.rb
 ```
 
-Here's what a freshly-generated integration test looks like:
+Here's what a freshly generated integration test looks like:
 
 ```ruby
 require 'test_helper'
@@ -675,7 +941,7 @@ each of the seven default actions, you can use the following command:
 $ bin/rails generate test_unit:scaffold article
 ...
 invoke  test_unit
-create test/controllers/articles_controller_test.rb
+create    test/controllers/articles_controller_test.rb
 ...
 ```
 
@@ -685,9 +951,8 @@ Let's take a look at one such test, `test_should_get_index` from the file `artic
 # articles_controller_test.rb
 class ArticlesControllerTest < ActionDispatch::IntegrationTest
   test "should get index" do
-    get '/articles'
+    get articles_url
     assert_response :success
-    assert_includes @response.body, 'Articles'
   end
 end
 ```
@@ -697,18 +962,13 @@ and also ensuring that the right response body has been generated.
 
 The `get` method kicks off the web request and populates the results into the `@response`. It can accept up to 6 arguments:
 
-* The action of the controller you are requesting.
-  This can be in the form of a string or a route (i.e. `articles_url`).
-
+* The URI of the controller action you are requesting.
+  This can be in the form of a string or a route helper (e.g. `articles_url`).
 * `params`: option with a hash of request parameters to pass into the action
   (e.g. query string parameters or article variables).
-
 * `headers`: for setting the headers that will be passed with the request.
-
 * `env`: for customizing the request environment as needed.
-
 * `xhr`: whether the request is Ajax request or not. Can be set to true for marking the request as Ajax.
-
 * `as`: for encoding the request with different content type. Supports `:json` by default.
 
 All of these keyword arguments are optional.
@@ -716,13 +976,13 @@ All of these keyword arguments are optional.
 Example: Calling the `:show` action, passing an `id` of 12 as the `params` and setting `HTTP_REFERER` header:
 
 ```ruby
-get :show, params: { id: 12 }, headers: { "HTTP_REFERER" => "http://example.com/home" }
+get article_url, params: { id: 12 }, headers: { "HTTP_REFERER" => "http://example.com/home" }
 ```
 
 Another example: Calling the `:update` action, passing an `id` of 12 as the `params` as an Ajax request.
 
 ```ruby
-get update_url, params: { id: 12 }, xhr: true
+patch article_url, params: { id: 12 }, xhr: true
 ```
 
 NOTE: If you try running `test_should_create_article` test from `articles_controller_test.rb` it will fail on account of the newly added model level validation and rightly so.
@@ -732,7 +992,7 @@ Let us modify `test_should_create_article` test in `articles_controller_test.rb`
 ```ruby
 test "should create article" do
   assert_difference('Article.count') do
-    post '/article', params: { article: { title: 'Some title' } }
+    post articles_url, params: { article: { body: 'Rails is awesome!', title: 'Hello Rails' } }
   end
 
   assert_redirected_to article_path(Article.last)
@@ -741,6 +1001,13 @@ end
 
 Now you can try running all the tests and they should pass.
 
+NOTE: If you followed the steps in the Basic Authentication section, you'll need to add the following to the `setup` block to get all the tests passing:
+
+```ruby
+request.headers['Authorization'] = ActionController::HttpAuthentication::Basic.
+  encode_credentials('dhh', 'secret')
+```
+
 ### Available Request Types for Functional Tests
 
 If you're familiar with the HTTP protocol, you'll know that `get` is a type of request. There are 6 request types supported in Rails functional tests:
@@ -763,7 +1030,7 @@ To test AJAX requests, you can specify the `xhr: true` option to `get`, `post`,
 
 ```ruby
 test "ajax request" do
-  article = articles(:first)
+  article = articles(:one)
   get article_url(article), xhr: true
 
   assert_equal 'hello world', @response.body
@@ -789,27 +1056,38 @@ cookies["are_good_for_u"]     cookies[:are_good_for_u]
 
 ### Instance Variables Available
 
-You also have access to three instance variables in your functional tests:
+You also have access to three instance variables in your functional tests, after a request is made:
 
 * `@controller` - The controller processing the request
 * `@request` - The request object
 * `@response` - The response object
 
+
+```ruby
+class ArticlesControllerTest < ActionDispatch::IntegrationTest
+  test "should get index" do
+    get articles_url
+
+    assert_equal "index", @controller.action_name
+    assert_equal "application/x-www-form-urlencoded", @request.media_type
+    assert_match "Articles", @response.body
+  end
+end
+```
+
 ### Setting Headers and CGI variables
 
-[HTTP headers](http://tools.ietf.org/search/rfc2616#section-5.3)
+[HTTP headers](https://tools.ietf.org/search/rfc2616#section-5.3)
 and
-[CGI variables](http://tools.ietf.org/search/rfc3875#section-4.1)
-can be set directly on the `@request` instance variable:
+[CGI variables](https://tools.ietf.org/search/rfc3875#section-4.1)
+can be passed as headers:
 
 ```ruby
 # setting an HTTP Header
-@request.headers["Accept"] = "text/plain, text/html"
-get articles_url # simulate the request with custom header
+get articles_url, headers: { "Content-Type": "text/plain" } # simulate the request with custom header
 
 # setting a CGI variable
-@request.headers["HTTP_REFERER"] = "http://example.com/home"
-post article_url # simulate the request with custom env variable
+get articles_url, headers: { "HTTP_REFERER": "http://example.com/home" } # simulate the request with custom env variable
 ```
 
 ### Testing `flash` notices
@@ -845,7 +1123,7 @@ F
 Finished in 0.114870s, 8.7055 runs/s, 34.8220 assertions/s.
 
   1) Failure:
-ArticlesControllerTest#test_should_create_article [/Users/zzak/code/bench/sharedapp/test/controllers/articles_controller_test.rb:16]:
+ArticlesControllerTest#test_should_create_article [/test/controllers/articles_controller_test.rb:16]:
 --- expected
 +++ actual
 @@ -1 +1 @@
@@ -894,7 +1172,7 @@ Let's write a test for the `:show` action:
 ```ruby
 test "should show article" do
   article = articles(:one)
-  get '/article', params: { id: article.id }
+  get article_url(article)
   assert_response :success
 end
 ```
@@ -920,7 +1198,7 @@ We can also add a test for updating an existing Article.
 test "should update article" do
   article = articles(:one)
 
-  patch '/article', params: { id: article.id, article: { title: "updated" } }
+  patch article_url(article), params: { article: { title: "updated" } }
 
   assert_redirected_to article_path(article)
   # Reload association to fetch updated data and assert that title is updated.
@@ -963,7 +1241,7 @@ class ArticlesControllerTest < ActionDispatch::IntegrationTest
   end
 
   test "should update article" do
-    patch '/article', params: { id: @article.id, article: { title: "updated" } }
+    patch article_url(@article), params: { article: { title: "updated" } }
 
     assert_redirected_to article_path(@article)
     # Reload association to fetch updated data and assert that title is updated.
@@ -981,11 +1259,11 @@ To avoid code duplication, you can add your own test helpers.
 Sign in helper can be a good example:
 
 ```ruby
-#test/test_helper.rb
+# test/test_helper.rb
 
 module SignInHelper
-  def sign_in(user)
-    session[:user_id] = user.id
+  def sign_in_as(user)
+    post sign_in_url(email: user.email, password: user.password)
   end
 end
 
@@ -1001,7 +1279,7 @@ class ProfileControllerTest < ActionDispatch::IntegrationTest
 
   test "should show profile" do
     # helper is now reusable from any controller test case
-    sign_in users(:david)
+    sign_in_as users(:david)
 
     get profile_url
     assert_response :success
@@ -1012,7 +1290,7 @@ end
 Testing Routes
 --------------
 
-Like everything else in your Rails application, you can test your routes.
+Like everything else in your Rails application, you can test your routes. Route tests reside in `test/controllers/` or are part of controller tests.
 
 NOTE: If your application has complex routes, Rails provides a number of useful helpers to test them.
 
@@ -1144,7 +1422,7 @@ In order to test that your mailer is working as expected, you can use unit tests
 
 For the purposes of unit testing a mailer, fixtures are used to provide an example of how the output _should_ look. Because these are example emails, and not Active Record data like the other fixtures, they are kept in their own subdirectory apart from the other fixtures. The name of the directory within `test/fixtures` directly corresponds to the name of the mailer. So, for a mailer named `UserMailer`, the fixtures should reside in `test/fixtures/user_mailer` directory.
 
-When you generated your mailer, the generator creates stub fixtures for each of the mailers actions. If you didn't use the generator, you'll have to create those files yourself.
+If you generated your mailer, the generator does not create stub fixtures for the mailers actions. You'll have to create those files yourself as described above.
 
 #### The Basic Test Case
 
@@ -1178,6 +1456,10 @@ variable. We then ensure that it was sent (the first assert), then, in the
 second batch of assertions, we ensure that the email does indeed contain what we
 expect. The helper `read_fixture` is used to read in the content from this file.
 
+NOTE: `email.body.to_s` is present when there's only one (HTML or text) part present.
+If the mailer provides both, you can test your fixture against specific parts
+with `email.text_part.body.to_s` or `email.html_part.body.to_s`.
+
 Here's the content of the `invite` fixture:
 
 ```
@@ -1216,7 +1498,7 @@ class UserControllerTest < ActionDispatch::IntegrationTest
 
     assert_equal "You have been invited by me@example.com", invite_email.subject
     assert_equal 'friend@example.com', invite_email.to[0]
-    assert_match(/Hi friend@example.com/, invite_email.body.to_s)
+    assert_match(/Hi friend@example\.com/, invite_email.body.to_s)
   end
 end
 ```
@@ -1244,7 +1526,7 @@ class BillingJobTest < ActiveJob::TestCase
 end
 ```
 
-This test is pretty simple and only asserts that the job get the work done
+This test is pretty simple and only asserts that the job got the work done
 as expected.
 
 By default, `ActiveJob::TestCase` will set the queue adapter to `:test` so that
@@ -1287,7 +1569,7 @@ Here is an example using the [`travel_to`](http://api.rubyonrails.org/classes/Ac
 user = User.create(name: 'Gaurish', activation_date: Date.new(2004, 10, 24))
 assert_not user.applicable_for_gifting?
 travel_to Date.new(2004, 11, 24) do
-  assert_equal Date.new(2004, 10, 24), user.activation_date # inside the travel_to block `Date.current` is mocked
+  assert_equal Date.new(2004, 10, 24), user.activation_date # inside the `travel_to` block `Date.current` is mocked
   assert user.applicable_for_gifting?
 end
 assert_equal Date.new(2004, 10, 24), user.activation_date # The change was visible only inside the `travel_to` block.
diff --git a/guides/source/threading_and_code_execution.md b/guides/source/threading_and_code_execution.md
new file mode 100644
index 0000000000..3d3d31b97e
--- /dev/null
+++ b/guides/source/threading_and_code_execution.md
@@ -0,0 +1,324 @@
+**DO NOT READ THIS FILE ON GITHUB, GUIDES ARE PUBLISHED ON http://guides.rubyonrails.org.**
+
+Threading and Code Execution in Rails
+=====================================
+
+After reading this guide, you will know:
+
+* What code Rails will automatically execute concurrently
+* How to integrate manual concurrency with Rails internals
+* How to wrap all application code
+* How to affect application reloading
+
+--------------------------------------------------------------------------------
+
+Automatic Concurrency
+---------------------
+
+Rails automatically allows various operations to be performed at the same time.
+
+When using a threaded web server, such as the default Puma, multiple HTTP
+requests will be served simultaneously, with each request provided its own
+controller instance.
+
+Threaded Active Job adapters, including the built-in Async, will likewise
+execute several jobs at the same time. Action Cable channels are managed this
+way too.
+
+These mechanisms all involve multiple threads, each managing work for a unique
+instance of some object (controller, job, channel), while sharing the global
+process space (such as classes and their configurations, and global variables).
+As long as your code doesn't modify any of those shared things, it can mostly
+ignore that other threads exist.
+
+The rest of this guide describes the mechanisms Rails uses to make it "mostly
+ignorable", and how extensions and applications with special needs can use them.
+
+Executor
+--------
+
+The Rails Executor separates application code from framework code: any time the
+framework invokes code you've written in your application, it will be wrapped by
+the Executor.
+
+The Executor consists of two callbacks: `to_run` and `to_complete`. The Run
+callback is called before the application code, and the Complete callback is
+called after.
+
+### Default callbacks
+
+In a default Rails application, the Executor callbacks are used to:
+
+* track which threads are in safe positions for autoloading and reloading
+* enable and disable the Active Record query cache
+* return acquired Active Record connections to the pool
+* constrain internal cache lifetimes
+
+Prior to Rails 5.0, some of these were handled by separate Rack middleware
+classes (such as `ActiveRecord::ConnectionAdapters::ConnectionManagement`), or
+directly wrapping code with methods like
+`ActiveRecord::Base.connection_pool.with_connection`. The Executor replaces
+these with a single more abstract interface.
+
+### Wrapping application code
+
+If you're writing a library or component that will invoke application code, you
+should wrap it with a call to the executor:
+
+```ruby
+Rails.application.executor.wrap do
+  # call application code here
+end
+```
+
+TIP: If you repeatedly invoke application code from a long-running process, you
+may want to wrap using the Reloader instead.
+
+Each thread should be wrapped before it runs application code, so if your
+application manually delegates work to other threads, such as via `Thread.new`
+or Concurrent Ruby features that use thread pools, you should immediately wrap
+the block:
+
+```ruby
+Thread.new do
+  Rails.application.executor.wrap do
+    # your code here
+  end
+end
+```
+
+NOTE: Concurrent Ruby uses a `ThreadPoolExecutor`, which it sometimes configures
+with an `executor` option. Despite the name, it is unrelated.
+
+The Executor is safely re-entrant; if it is already active on the current
+thread, `wrap` is a no-op.
+
+If it's impractical to wrap the application code in a block (for
+example, the Rack API makes this problematic), you can also use the `run!` /
+`complete!` pair:
+
+```ruby
+Thread.new do
+  execution_context = Rails.application.executor.run!
+  # your code here
+ensure
+  execution_context.complete! if execution_context
+end
+```
+
+### Concurrency
+
+The Executor will put the current thread into `running` mode in the Load
+Interlock. This operation will block temporarily if another thread is currently
+either autoloading a constant or unloading/reloading the application.
+
+Reloader
+--------
+
+Like the Executor, the Reloader also wraps application code. If the Executor is
+not already active on the current thread, the Reloader will invoke it for you,
+so you only need to call one. This also guarantees that everything the Reloader
+does, including all its callback invocations, occurs wrapped inside the
+Executor.
+
+```ruby
+Rails.application.reloader.wrap do
+  # call application code here
+end
+```
+
+The Reloader is only suitable where a long-running framework-level process
+repeatedly calls into application code, such as for a web server or job queue.
+Rails automatically wraps web requests and Active Job workers, so you'll rarely
+need to invoke the Reloader for yourself. Always consider whether the Executor
+is a better fit for your use case.
+
+### Callbacks
+
+Before entering the wrapped block, the Reloader will check whether the running
+application needs to be reloaded -- for example, because a model's source file has
+been modified. If it determines a reload is required, it will wait until it's
+safe, and then do so, before continuing. When the application is configured to
+always reload regardless of whether any changes are detected, the reload is
+instead performed at the end of the block.
+
+The Reloader also provides `to_run` and `to_complete` callbacks; they are
+invoked at the same points as those of the Executor, but only when the current
+execution has initiated an application reload. When no reload is deemed
+necessary, the Reloader will invoke the wrapped block with no other callbacks.
+
+### Class Unload
+
+The most significant part of the reloading process is the Class Unload, where
+all autoloaded classes are removed, ready to be loaded again. This will occur
+immediately before either the Run or Complete callback, depending on the
+`reload_classes_only_on_change` setting.
+
+Often, additional reloading actions need to be performed either just before or
+just after the Class Unload, so the Reloader also provides `before_class_unload`
+and `after_class_unload` callbacks.
+
+### Concurrency
+
+Only long-running "top level" processes should invoke the Reloader, because if
+it determines a reload is needed, it will block until all other threads have
+completed any Executor invocations.
+
+If this were to occur in a "child" thread, with a waiting parent inside the
+Executor, it would cause an unavoidable deadlock: the reload must occur before
+the child thread is executed, but it cannot be safely performed while the parent
+thread is mid-execution. Child threads should use the Executor instead.
+
+Framework Behavior
+------------------
+
+The Rails framework components use these tools to manage their own concurrency
+needs too.
+
+`ActionDispatch::Executor` and `ActionDispatch::Reloader` are Rack middlewares
+that wraps the request with a supplied Executor or Reloader, respectively. They
+are automatically included in the default application stack. The Reloader will
+ensure any arriving HTTP request is served with a freshly-loaded copy of the
+application if any code changes have occurred.
+
+Active Job also wraps its job executions with the Reloader, loading the latest
+code to execute each job as it comes off the queue.
+
+Action Cable uses the Executor instead: because a Cable connection is linked to
+a specific instance of a class, it's not possible to reload for every arriving
+websocket message. Only the message handler is wrapped, though; a long-running
+Cable connection does not prevent a reload that's triggered by a new incoming
+request or job. Instead, Action Cable uses the Reloader's `before_class_unload`
+callback to disconnect all its connections. When the client automatically
+reconnects, it will be speaking to the new version of the code.
+
+The above are the entry points to the framework, so they are responsible for
+ensuring their respective threads are protected, and deciding whether a reload
+is necessary. Other components only need to use the Executor when they spawn
+additional threads.
+
+### Configuration
+
+The Reloader only checks for file changes when `cache_classes` is false and
+`reload_classes_only_on_change` is true (which is the default in the
+`development` environment).
+
+When `cache_classes` is true (in `production`, by default), the Reloader is only
+a pass-through to the Executor.
+
+The Executor always has important work to do, like database connection
+management. When `cache_classes` and `eager_load` are both true (`production`),
+no autoloading or class reloading will occur, so it does not need the Load
+Interlock. If either of those are false (`development`), then the Executor will
+use the Load Interlock to ensure constants are only loaded when it is safe.
+
+Load Interlock
+--------------
+
+The Load Interlock allows autoloading and reloading to be enabled in a
+multi-threaded runtime environment.
+
+When one thread is performing an autoload by evaluating the class definition
+from the appropriate file, it is important no other thread encounters a
+reference to the partially-defined constant.
+
+Similarly, it is only safe to perform an unload/reload when no application code
+is in mid-execution: after the reload, the `User` constant, for example, may
+point to a different class. Without this rule, a poorly-timed reload would mean
+`User.new.class == User`, or even `User == User`, could be false.
+
+Both of these constraints are addressed by the Load Interlock. It keeps track of
+which threads are currently running application code, loading a class, or
+unloading autoloaded constants.
+
+Only one thread may load or unload at a time, and to do either, it must wait
+until no other threads are running application code. If a thread is waiting to
+perform a load, it doesn't prevent other threads from loading (in fact, they'll
+cooperate, and each perform their queued load in turn, before all resuming
+running together).
+
+### `permit_concurrent_loads`
+
+The Executor automatically acquires a `running` lock for the duration of its
+block, and autoload knows when to upgrade to a `load` lock, and switch back to
+`running` again afterwards.
+
+Other blocking operations performed inside the Executor block (which includes
+all application code), however, can needlessly retain the `running` lock. If
+another thread encounters a constant it must autoload, this can cause a
+deadlock.
+
+For example, assuming `User` is not yet loaded, the following will deadlock:
+
+```ruby
+Rails.application.executor.wrap do
+  th = Thread.new do
+    Rails.application.executor.wrap do
+      User # inner thread waits here; it cannot load
+           # User while another thread is running
+    end
+  end
+
+  th.join # outer thread waits here, holding 'running' lock
+end
+```
+
+To prevent this deadlock, the outer thread can `permit_concurrent_loads`. By
+calling this method, the thread guarantees it will not dereference any
+possibly-autoloaded constant inside the supplied block. The safest way to meet
+that promise is to put it as close as possible to the blocking call:
+
+```ruby
+Rails.application.executor.wrap do
+  th = Thread.new do
+    Rails.application.executor.wrap do
+      User # inner thread can acquire the load lock,
+           # load User, and continue
+    end
+  end
+
+  ActiveSupport::Dependencies.interlock.permit_concurrent_loads do
+    th.join # outer thread waits here, but has no lock
+  end
+end
+```
+
+Another example, using Concurrent Ruby:
+
+```ruby
+Rails.application.executor.wrap do
+  futures = 3.times.collect do |i|
+    Concurrent::Future.execute do
+      Rails.application.executor.wrap do
+        # do work here
+      end
+    end
+  end
+
+  values = ActiveSupport::Dependencies.interlock.permit_concurrent_loads do
+    futures.collect(&:value)
+  end
+end
+```
+
+
+### ActionDispatch::DebugLocks
+
+If your application is deadlocking and you think the Load Interlock may be
+involved, you can temporarily add the ActionDispatch::DebugLocks middleware to
+`config/application.rb`:
+
+```ruby
+config.middleware.insert_before Rack::Sendfile,
+                                  ActionDispatch::DebugLocks
+```
+
+If you then restart the application and re-trigger the deadlock condition,
+`/rails/locks` will show a summary of all threads currently known to the
+interlock, which lock level they are holding or awaiting, and their current
+backtrace.
+
+Generally a deadlock will be caused by the interlock conflicting with some other
+external lock or blocking I/O call. Once you find it, you can wrap it with
+`permit_concurrent_loads`.
+
diff --git a/guides/source/upgrading_ruby_on_rails.md b/guides/source/upgrading_ruby_on_rails.md
index 82080c4def..bb4ef26876 100644
--- a/guides/source/upgrading_ruby_on_rails.md
+++ b/guides/source/upgrading_ruby_on_rails.md
@@ -1,7 +1,7 @@
 **DO NOT READ THIS FILE ON GITHUB, GUIDES ARE PUBLISHED ON http://guides.rubyonrails.org.**
 
-A Guide for Upgrading Ruby on Rails
-===================================
+Upgrading Ruby on Rails
+=======================
 
 This guide provides steps to be followed when you upgrade your applications to a newer version of Ruby on Rails. These steps are also available in individual release guides.
 
@@ -27,7 +27,7 @@ The process should go as follows:
 3. Fix tests and deprecated features.
 4. Move to the latest patch version of the next minor version.
 
-Repeat this process until you reach your target Rails version. Each time you move versions, you will need to change the Rails version number in the Gemfile (and possibly other gem versions) and run `bundle update`. Then run the Update task mentioned below to update configuration files, then run your tests.
+Repeat this process until you reach your target Rails version. Each time you move versions, you will need to change the Rails version number in the `Gemfile` (and possibly other gem versions) and run `bundle update`. Then run the Update task mentioned below to update configuration files, then run your tests.
 
 You can find a list of all released Rails versions [here](https://rubygems.org/gems/rails/versions).
 
@@ -44,8 +44,8 @@ TIP: Ruby 1.8.7 p248 and p249 have marshaling bugs that crash Rails. Ruby Enterp
 
 ### The Update Task
 
-Rails provides the `app:update` task (`rails:update` on 4.2 and earlier). After updating the Rails version
-in the Gemfile, run this task.
+Rails provides the `app:update` task (`rake rails:update` on 4.2 and earlier). After updating the Rails version
+in the `Gemfile`, run this task.
 This will help you with the creation of new files and changes of old files in an
 interactive session.
 
@@ -65,17 +65,54 @@ Overwrite /myapp/config/application.rb? (enter "h" for help) [Ynaqdh]
 
 Don't forget to review the difference, to see if there were any unexpected changes.
 
+Upgrading from Rails 5.0 to Rails 5.1
+-------------------------------------
+
+For more information on changes made to Rails 5.1 please see the [release notes](5_1_release_notes.html).
+
+### Top-level `HashWithIndifferentAccess` is soft-deprecated
+
+If your application uses the the top-level `HashWithIndifferentAccess` class, you
+should slowly move your code to instead use `ActiveSupport::HashWithIndifferentAccess`.
+
+It is only soft-deprecated, which means that your code will not break at the
+moment and no deprecation warning will be displayed, but this constant will be
+removed in the future.
+
+Also, if you have pretty old YAML documents containing dumps of such objects,
+you may need to load and dump them again to make sure that they reference
+the right constant, and that loading them won't break in the future.
+
+### `application.secrets` now loaded with all keys as symbols
+
+If your application stores nested configuration in `config/secrets.yml`, all keys
+are now loaded as symbols, so access using strings should be changed.
+
+From:
+
+```ruby
+Rails.application.secrets[:smtp_settings]["address"]
+```
+
+To:
+
+```ruby
+Rails.application.secrets[:smtp_settings][:address]
+```
+
 Upgrading from Rails 4.2 to Rails 5.0
 -------------------------------------
 
-### Ruby 2.2.2+
+For more information on changes made to Rails 5.0 please see the [release notes](5_0_release_notes.html).
 
-From Ruby on Rails 5.0 onwards, Ruby 2.2.2+ is the only supported version. 
-Make sure you are on Ruby 2.2.2 version or greater, before you proceed. 
+### Ruby 2.2.2+ required
 
-### Active Record models now inherit from ApplicationRecord by default
+From Ruby on Rails 5.0 onwards, Ruby 2.2.2+ is the only supported Ruby version.
+Make sure you are on Ruby 2.2.2 version or greater, before you proceed.
 
-In Rails 4.2 an Active Record model inherits from `ActiveRecord::Base`. In Rails 5.0,
+### Active Record Models Now Inherit from ApplicationRecord by Default
+
+In Rails 4.2, an Active Record model inherits from `ActiveRecord::Base`. In Rails 5.0,
 all models inherit from `ApplicationRecord`.
 
 `ApplicationRecord` is a new superclass for all app models, analogous to app
@@ -83,7 +120,7 @@ controllers subclassing `ApplicationController` instead of
 `ActionController::Base`. This gives apps a single spot to configure app-wide
 model behavior.
 
-When upgrading from Rails 4.2 to Rails 5.0 you need to create an
+When upgrading from Rails 4.2 to Rails 5.0, you need to create an
 `application_record.rb` file in `app/models/` and add the following content:
 
 ```
@@ -92,7 +129,9 @@ class ApplicationRecord < ActiveRecord::Base
 end
 ```
 
-### Halting callback chains via `throw(:abort)`
+Then make sure that all your models inherit from it.
+
+### Halting Callback Chains via `throw(:abort)`
 
 In Rails 4.2, when a 'before' callback returns `false` in Active Record
 and Active Model, then the entire callback chain is halted. In other words,
@@ -117,12 +156,12 @@ halted the chain when any value was returned.
 
 See [#17227](https://github.com/rails/rails/pull/17227) for more details.
 
-### ActiveJob jobs now inherit from ApplicationJob by default
+### ActiveJob Now Inherits from ApplicationJob by Default
 
-In Rails 4.2 an ActiveJob inherits from `ActiveJob::Base`. In Rails 5.0 this
+In Rails 4.2, an Active Job inherits from `ActiveJob::Base`. In Rails 5.0, this
 behavior has changed to now inherit from `ApplicationJob`.
 
-When upgrading from Rails 4.2 to Rails 5.0 you need to create an
+When upgrading from Rails 4.2 to Rails 5.0, you need to create an
 `application_job.rb` file in `app/jobs/` and add the following content:
 
 ```
@@ -134,16 +173,249 @@ Then make sure that all your job classes inherit from it.
 
 See [#19034](https://github.com/rails/rails/pull/19034) for more details.
 
+### Rails Controller Testing
+
+#### Extraction of some helper methods to `rails-controller-testing`
+
+`assigns` and `assert_template` have been extracted to the `rails-controller-testing` gem. To
+continue using these methods in your controller tests, add `gem 'rails-controller-testing'` to
+your `Gemfile`.
+
+If you are using Rspec for testing, please see the extra configuration required in the gem's
+documentation.
+
+#### New behavior when uploading files
+
+If you are using `ActionDispatch::Http::UploadedFile` in your tests to
+upload files, you will need to change to use the similar `Rack::Test::UploadedFile`
+class instead.
+
+See [#26404](https://github.com/rails/rails/issues/26404) for more details.
+
+### Autoloading is Disabled After Booting in the Production Environment
+
+Autoloading is now disabled after booting in the production environment by
+default.
+
+Eager loading the application is part of the boot process, so top-level
+constants are fine and are still autoloaded, no need to require their files.
+
+Constants in deeper places only executed at runtime, like regular method bodies,
+are also fine because the file defining them will have been eager loaded while booting.
+
+For the vast majority of applications this change needs no action. But in the
+very rare event that your application needs autoloading while running in
+production mode, set `Rails.application.config.enable_dependency_loading` to
+true.
+
+### XML Serialization
+
+`ActiveModel::Serializers::Xml` has been extracted from Rails to the `activemodel-serializers-xml`
+gem. To continue using XML serialization in your application, add `gem 'activemodel-serializers-xml'`
+to your `Gemfile`.
+
+### Removed Support for Legacy `mysql` Database Adapter
+
+Rails 5 removes support for the legacy `mysql` database adapter. Most users should be able to
+use `mysql2` instead. It will be converted to a separate gem when we find someone to maintain
+it.
+
+### Removed Support for Debugger
+
+`debugger` is not supported by Ruby 2.2 which is required by Rails 5. Use `byebug` instead.
+
+### Use bin/rails for running tasks and tests
+
+Rails 5 adds the ability to run tasks and tests through `bin/rails` instead of rake. Generally
+these changes are in parallel with rake, but some were ported over altogether.
+
+To use the new test runner simply type `bin/rails test`.
+
+`rake dev:cache` is now `rails dev:cache`.
+
+Run `bin/rails` to see the list of commands available.
+
+### `ActionController::Parameters` No Longer Inherits from `HashWithIndifferentAccess`
+
+Calling `params` in your application will now return an object instead of a hash. If your
+parameters are already permitted, then you will not need to make any changes. If you are using `map`
+and other methods that depend on being able to read the hash regardless of `permitted?` you will
+need to upgrade your application to first permit and then convert to a hash.
+
+    params.permit([:proceed_to, :return_to]).to_h
+
+### `protect_from_forgery` Now Defaults to `prepend: false`
+
+`protect_from_forgery` defaults to `prepend: false` which means that it will be inserted into
+the callback chain at the point in which you call it in your application. If you want
+`protect_from_forgery` to always run first, then you should change your application to use
+`protect_from_forgery prepend: true`.
+
+### Default Template Handler is Now RAW
+
+Files without a template handler in their extension will be rendered using the raw handler.
+Previously Rails would render files using the ERB template handler.
+
+If you do not want your file to be handled via the raw handler, you should add an extension
+to your file that can be parsed by the appropriate template handler.
+
+### Added Wildcard Matching for Template Dependencies
+
+You can now use wildcard matching for your template dependencies. For example, if you were
+defining your templates as such:
+
+```erb
+<% # Template Dependency: recordings/threads/events/subscribers_changed %>
+<% # Template Dependency: recordings/threads/events/completed %>
+<% # Template Dependency: recordings/threads/events/uncompleted %>
+```
+
+You can now just call the dependency once with a wildcard.
+
+```erb
+<% # Template Dependency: recordings/threads/events/* %>
+```
+
+### `ActionView::Helpers::RecordTagHelper` moved to external gem (record_tag_helper)
+
+`content_tag_for` and `div_for` have been removed in favor of just using `content_tag`. To continue using the older methods, add the `record_tag_helper` gem to your `Gemfile`:
+
+```ruby
+gem 'record_tag_helper', '~> 1.0'
+```
+
+See [#18411](https://github.com/rails/rails/pull/18411) for more details.
+
+### Removed Support for `protected_attributes` Gem
+
+The `protected_attributes` gem is no longer supported in Rails 5.
+
+### Removed support for `activerecord-deprecated_finders` gem
+
+The `activerecord-deprecated_finders` gem is no longer supported in Rails 5.
+
+### `ActiveSupport::TestCase` Default Test Order is Now Random
+
+When tests are run in your application, the default order is now `:random`
+instead of `:sorted`. Use the following config option to set it back to `:sorted`.
+
+```ruby
+# config/environments/test.rb
+Rails.application.configure do
+  config.active_support.test_order = :sorted
+end
+```
+
+### `ActionController::Live` became a `Concern`
+
+If you include `ActionController::Live` in another module that is included in your controller, then you
+should also extend the module with `ActiveSupport::Concern`. Alternatively, you can use the `self.included` hook
+to include `ActionController::Live` directly to the controller once the `StreamingSupport` is included.
+
+This means that if your application used to have its own streaming module, the following code
+would break in production mode:
+
+```ruby
+# This is a work-around for streamed controllers performing authentication with Warden/Devise.
+# See https://github.com/plataformatec/devise/issues/2332
+# Authenticating in the router is another solution as suggested in that issue
+class StreamingSupport
+  include ActionController::Live # this won't work in production for Rails 5
+  # extend ActiveSupport::Concern # unless you uncomment this line.
+
+  def process(name)
+    super(name)
+  rescue ArgumentError => e
+    if e.message == 'uncaught throw :warden'
+      throw :warden
+    else
+      raise e
+    end
+  end
+end
+```
+
+### New Framework Defaults
+
+#### Active Record `belongs_to` Required by Default Option
+
+`belongs_to` will now trigger a validation error by default if the association is not present.
+
+This can be turned off per-association with `optional: true`.
+
+This default will be automatically configured in new applications. If existing application
+want to add this feature it will need to be turned on in an initializer.
+
+    config.active_record.belongs_to_required_by_default = true
+
+#### Per-form CSRF Tokens
+
+Rails 5 now supports per-form CSRF tokens to mitigate against code-injection attacks with forms
+created by JavaScript. With this option turned on, forms in your application will each have their
+own CSRF token that is specified to the action and method for that form.
+
+    config.action_controller.per_form_csrf_tokens = true
+
+#### Forgery Protection with Origin Check
+
+You can now configure your application to check if the HTTP `Origin` header should be checked
+against the site's origin as an additional CSRF defense. Set the following in your config to
+true:
+
+    config.action_controller.forgery_protection_origin_check = true
+
+#### Allow Configuration of Action Mailer Queue Name
+
+The default mailer queue name is `mailers`. This configuration option allows you to globally change
+the queue name. Set the following in your config:
+
+    config.action_mailer.deliver_later_queue_name = :new_queue_name
+
+#### Support Fragment Caching in Action Mailer Views
+
+Set `config.action_mailer.perform_caching` in your config to determine whether your Action Mailer views
+should support caching.
+
+    config.action_mailer.perform_caching = true
+
+#### Configure the Output of `db:structure:dump`
+
+If you're using `schema_search_path` or other PostgreSQL extensions, you can control how the schema is
+dumped. Set to `:all` to generate all dumps, or to `:schema_search_path` to generate from schema search path.
+
+    config.active_record.dump_schemas = :all
+
+#### Configure SSL Options to Enable HSTS with Subdomains
+
+Set the following in your config to enable HSTS when using subdomains:
+
+    config.ssl_options = { hsts: { subdomains: true } }
+
+#### Preserve Timezone of the Receiver
+
+When using Ruby 2.4, you can preserve the timezone of the receiver when calling `to_time`.
+
+    ActiveSupport.to_time_preserves_timezone = false
+
+### Changes with JSON/JSONB serialization
+
+In Rails 5.0, how JSON/JSONB attributes are serialized and deserialized changed. Now, if
+you set a column equal to a `String`, Active Record will no longer turn that string
+into a `Hash`, and will instead only return the string. This is not limited to code
+interacting with models, but also affects `:default` column settings in `db/schema.rb`.
+It is recommended that you do not set columns equal to a `String`, but pass a `Hash`
+instead, which will be converted to and from a JSON string automatically.
+
 Upgrading from Rails 4.1 to Rails 4.2
 -------------------------------------
 
 ### Web Console
 
-First, add `gem 'web-console', '~> 2.0'` to the `:development` group in your Gemfile and run `bundle install` (it won't have been included when you upgraded Rails). Once it's been installed, you can simply drop a reference to the console helper (i.e., `<%= console %>`) into any view you want to enable it for. A console will also be provided on any error page you view in your development environment.
+First, add `gem 'web-console', '~> 2.0'` to the `:development` group in your `Gemfile` and run `bundle install` (it won't have been included when you upgraded Rails). Once it's been installed, you can simply drop a reference to the console helper (i.e., `<%= console %>`) into any view you want to enable it for. A console will also be provided on any error page you view in your development environment.
 
 ### Responders
 
-`respond_with` and the class-level `respond_to` methods have been extracted to the `responders` gem. To use them, simply add `gem 'responders', '~> 2.0'` to your Gemfile. Calls to `respond_with` and `respond_to` (again, at the class level) will no longer work without having included the `responders` gem in your dependencies:
+`respond_with` and the class-level `respond_to` methods have been extracted to the `responders` gem. To use them, simply add `gem 'responders', '~> 2.0'` to your `Gemfile`. Calls to `respond_with` and `respond_to` (again, at the class level) will no longer work without having included the `responders` gem in your dependencies:
 
 ```ruby
 # app/controllers/users_controller.rb
@@ -287,7 +559,7 @@ Read the [gem's readme](https://github.com/rails/rails-html-sanitizer) for more
 The documentation for `PermitScrubber` and `TargetScrubber` explains how you
 can gain complete control over when and how elements should be stripped.
 
-If your application needs to use the old sanitizer implementation, include `rails-deprecated_sanitizer` in your Gemfile:
+If your application needs to use the old sanitizer implementation, include `rails-deprecated_sanitizer` in your `Gemfile`:
 
 ```ruby
 gem 'rails-deprecated_sanitizer'
@@ -345,7 +617,7 @@ migration DSL counterpart.
 
 The migration procedure is as follows:
 
-1. remove `gem "foreigner"` from the Gemfile.
+1. remove `gem "foreigner"` from the `Gemfile`.
 2. run `bundle install`.
 3. run `bin/rake db:schema:dump`.
 4. make sure that `db/schema.rb` contains every foreign key definition with
@@ -495,9 +767,9 @@ There are a few major changes related to JSON handling in Rails 4.1.
 MultiJSON has reached its [end-of-life](https://github.com/rails/rails/pull/10576)
 and has been removed from Rails.
 
-If your application currently depend on MultiJSON directly, you have a few options:
+If your application currently depends on MultiJSON directly, you have a few options:
 
-1. Add 'multi_json' to your Gemfile. Note that this might cease to work in the future
+1. Add 'multi_json' to your `Gemfile`. Note that this might cease to work in the future
 
 2. Migrate away from MultiJSON by using `obj.to_json`, and `JSON.parse(str)` instead.
 
@@ -538,7 +810,7 @@ part of the rewrite, the following features have been removed from the encoder:
 
 If your application depends on one of these features, you can get them back by
 adding the [`activesupport-json_encoder`](https://github.com/rails/activesupport-json_encoder)
-gem to your Gemfile.
+gem to your `Gemfile`.
 
 #### JSON representation of Time objects
 
@@ -834,7 +1106,7 @@ on the Rails blog.
 
 The errata for the `PATCH` verb [specifies that a 'diff' media type should be
 used with `PATCH`](http://www.rfc-editor.org/errata_search.php?rfc=5789). One
-such format is [JSON Patch](http://tools.ietf.org/html/rfc6902). While Rails
+such format is [JSON Patch](https://tools.ietf.org/html/rfc6902). While Rails
 does not support JSON Patch natively, it's easy enough to add support:
 
 ```
@@ -863,8 +1135,8 @@ full support for the last few changes in the specification.
 
 ### Gemfile
 
-Rails 4.0 removed the `assets` group from Gemfile. You'd need to remove that
-line from your Gemfile when upgrading. You should also update your application
+Rails 4.0 removed the `assets` group from `Gemfile`. You'd need to remove that
+line from your `Gemfile` when upgrading. You should also update your application
 file (in `config/application.rb`):
 
 ```ruby
@@ -875,7 +1147,7 @@ Bundler.require(*Rails.groups)
 
 ### vendor/plugins
 
-Rails 4.0 no longer supports loading plugins from `vendor/plugins`. You must replace any plugins by extracting them to gems and adding them to your Gemfile. If you choose not to make them gems, you can move them into, say, `lib/my_plugin/*` and add an appropriate initializer in `config/initializers/my_plugin.rb`.
+Rails 4.0 no longer supports loading plugins from `vendor/plugins`. You must replace any plugins by extracting them to gems and adding them to your `Gemfile`. If you choose not to make them gems, you can move them into, say, `lib/my_plugin/*` and add an appropriate initializer in `config/initializers/my_plugin.rb`.
 
 ### Active Record
 
@@ -942,7 +1214,7 @@ end
 
 ### Active Resource
 
-Rails 4.0 extracted Active Resource to its own gem. If you still need the feature you can add the [Active Resource gem](https://github.com/rails/activeresource) in your Gemfile.
+Rails 4.0 extracted Active Resource to its own gem. If you still need the feature you can add the [Active Resource gem](https://github.com/rails/activeresource) in your `Gemfile`.
 
 ### Active Model
 
@@ -979,7 +1251,7 @@ Please read [Pull Request #9978](https://github.com/rails/rails/pull/9978) for d
 
 * Rails 4.0 has deprecated `ActionController::Base.page_cache_extension` option. Use `ActionController::Base.default_static_extension` instead.
 
-* Rails 4.0 has removed Action and Page caching from Action Pack. You will need to add the `actionpack-action_caching` gem in order to use `caches_action` and the `actionpack-page_caching` to use `caches_pages` in your controllers.
+* Rails 4.0 has removed Action and Page caching from Action Pack. You will need to add the `actionpack-action_caching` gem in order to use `caches_action` and the `actionpack-page_caching` to use `caches_page` in your controllers.
 
 * Rails 4.0 has removed the XML parameters parser. You will need to add the `actionpack-xml_parser` gem if you require this feature.
 
@@ -1038,7 +1310,7 @@ get 'こんにちは', controller: 'welcome', action: 'index'
   get '/' => 'root#index'
 ```
 
-* Rails 4.0 has removed `ActionDispatch::BestStandardsSupport` middleware, `<!DOCTYPE html>` already triggers standards mode per http://msdn.microsoft.com/en-us/library/jj676915(v=vs.85).aspx and ChromeFrame header has been moved to `config.action_dispatch.default_headers`.
+* Rails 4.0 has removed `ActionDispatch::BestStandardsSupport` middleware, `<!DOCTYPE html>` already triggers standards mode per https://msdn.microsoft.com/en-us/library/jj676915(v=vs.85).aspx and ChromeFrame header has been moved to `config.action_dispatch.default_headers`.
 
 Remember you must also remove any references to the middleware from your application code, for example:
 
@@ -1070,6 +1342,10 @@ Also check your environment settings for `config.action_dispatch.best_standards_
 
 Rails 4.0 removes the `j` alias for `ERB::Util#json_escape` since `j` is already used for `ActionView::Helpers::JavaScriptHelper#escape_javascript`.
 
+#### Cache
+
+The caching method changed between Rails 3.x and 4.0. You should [change the cache namespace](http://guides.rubyonrails.org/caching_with_rails.html#activesupport-cache-store) and roll out with a cold cache.
+
 ### Helpers Loading Order
 
 The order in which helpers from more than one directory are loaded has changed in Rails 4.0. Previously, they were gathered and then sorted alphabetically. After upgrading to Rails 4.0, helpers will preserve the order of loaded directories and will be sorted alphabetically only within each directory. Unless you explicitly use the `helpers_path` parameter, this change will only impact the way of loading helpers from engines. If you rely on the ordering, you should check if correct methods are available after upgrade. If you would like to change the order in which engines are loaded, you can use `config.railties_order=` method.
@@ -1138,7 +1414,7 @@ config.active_record.mass_assignment_sanitizer = :strict
 
 ### vendor/plugins
 
-Rails 3.2 deprecates `vendor/plugins` and Rails 4.0 will remove them completely. While it's not strictly necessary as part of a Rails 3.2 upgrade, you can start replacing any plugins by extracting them to gems and adding them to your Gemfile. If you choose not to make them gems, you can move them into, say, `lib/my_plugin/*` and add an appropriate initializer in `config/initializers/my_plugin.rb`.
+Rails 3.2 deprecates `vendor/plugins` and Rails 4.0 will remove them completely. While it's not strictly necessary as part of a Rails 3.2 upgrade, you can start replacing any plugins by extracting them to gems and adding them to your `Gemfile`. If you choose not to make them gems, you can move them into, say, `lib/my_plugin/*` and add an appropriate initializer in `config/initializers/my_plugin.rb`.
 
 ### Active Record
 
@@ -1218,7 +1494,7 @@ config.assets.digest = true
 # config.assets.manifest = YOUR_PATH
 
 # Precompile additional assets (application.js, application.css, and all non-JS/CSS are already added)
-# config.assets.precompile += %w( search.js )
+# config.assets.precompile += %w( admin.js admin.css )
 
 # Force all access to the app over SSL, use Strict-Transport-Security, and use secure cookies.
 # config.force_ssl = true
diff --git a/guides/source/working_with_javascript_in_rails.md b/guides/source/working_with_javascript_in_rails.md
index c1dfcab6f3..c3dff1772c 100644
--- a/guides/source/working_with_javascript_in_rails.md
+++ b/guides/source/working_with_javascript_in_rails.md
@@ -24,11 +24,11 @@ In order to understand Ajax, you must first understand what a web browser does
 normally.
 
 When you type `http://localhost:3000` into your browser's address bar and hit
-'Go,' the browser (your 'client') makes a request to the server. It parses the
+'Go', the browser (your 'client') makes a request to the server. It parses the
 response, then fetches all associated assets, like JavaScript files,
 stylesheets and images. It then assembles the page. If you click a link, it
 does the same process: fetch the page, fetch the assets, put it all together,
-show you the results. This is called the 'request response cycle.'
+show you the results. This is called the 'request response cycle'.
 
 JavaScript can also make requests to the server, and parse the response. It
 also has the ability to update information on the page. Combining these two
@@ -57,7 +57,7 @@ will show you how Rails can help you write websites in this way, but it's
 all built on top of this fairly simple technique.
 
 Unobtrusive JavaScript
--------------------------------------
+----------------------
 
 Rails uses a technique called "Unobtrusive JavaScript" to handle attaching
 JavaScript to the DOM. This is generally considered to be a best-practice
@@ -139,7 +139,9 @@ JavaScript) in this style, and you can expect that many libraries will also
 follow this pattern.
 
 Built-in Helpers
-----------------------
+----------------
+
+### Remote elements
 
 Rails provides a bunch of view helper methods written in Ruby to assist you
 in generating HTML. Sometimes, you want to add a little Ajax to those elements,
@@ -149,18 +151,22 @@ Because of Unobtrusive JavaScript, the Rails "Ajax helpers" are actually in two
 parts: the JavaScript half and the Ruby half.
 
 Unless you have disabled the Asset Pipeline,
-[rails.js](https://github.com/rails/jquery-ujs/blob/master/src/rails.js)
+[rails-ujs](https://github.com/rails/rails/tree/master/actionview/app/assets/javascripts)
 provides the JavaScript half, and the regular Ruby view helpers add appropriate
 tags to your DOM.
 
-### form_for
+You can read below about the different events that are fired dealing with
+remote elements inside your application.
 
-[`form_for`](http://api.rubyonrails.org/classes/ActionView/Helpers/FormHelper.html#method-i-form_for)
-is a helper that assists with writing forms. `form_for` takes a `:remote`
-option. It works like this:
+#### form_with
+
+[`form_with`](http://api.rubyonrails.org/classes/ActionView/Helpers/FormHelper.html#method-i-form_with)
+is a helper that assists with writing forms. By default, `form_with` assumes that
+your form will be using Ajax. You can opt out of this behavior by
+passing the `:local` option `form_with`.
 
 ```erb
-<%= form_for(@article, remote: true) do |f| %>
+<%= form_with(model: @article) do |f| %>
   ...
 <% end %>
 ```
@@ -168,7 +174,7 @@ option. It works like this:
 This will generate the following HTML:
 
 ```html
-<form accept-charset="UTF-8" action="/articles" class="new_article" data-remote="true" id="new_article" method="post">
+<form action="/articles" accept-charset="UTF-8" method="post" data-remote="true">
   ...
 </form>
 ```
@@ -182,39 +188,21 @@ bind to the `ajax:success` event. On failure, use `ajax:error`. Check it out:
 
 ```coffeescript
 $(document).ready ->
-  $("#new_article").on("ajax:success", (e, data, status, xhr) ->
+  $("#new_article").on("ajax:success", (event) ->
+    [data, status, xhr] = event.detail
     $("#new_article").append xhr.responseText
-  ).on "ajax:error", (e, xhr, status, error) ->
+  ).on "ajax:error", (event) ->
     $("#new_article").append "<p>ERROR</p>"
 ```
 
 Obviously, you'll want to be a bit more sophisticated than that, but it's a
-start. You can see more about the events [in the jquery-ujs wiki](https://github.com/rails/jquery-ujs/wiki/ajax).
-
-### form_tag
-
-[`form_tag`](http://api.rubyonrails.org/classes/ActionView/Helpers/FormTagHelper.html#method-i-form_tag)
-is very similar to `form_for`. It has a `:remote` option that you can use like
-this:
-
-```erb
-<%= form_tag('/articles', remote: true) do %>
-  ...
-<% end %>
-```
-
-This will generate the following HTML:
-
-```html
-<form accept-charset="UTF-8" action="/articles" data-remote="true" method="post">
-  ...
-</form>
-```
+start.
 
-Everything else is the same as `form_for`. See its documentation for full
-details.
+NOTE: As of Rails 5.1 and the new `rails-ujs`, the parameters `data, status, xhr`
+have been bundled into `event.detail`. For information about the previously used
+`jquery-ujs` in Rails 5 and earlier, read the [`jquery-ujs` wiki](https://github.com/rails/jquery-ujs/wiki/ajax).
 
-### link_to
+#### link_to
 
 [`link_to`](http://api.rubyonrails.org/classes/ActionView/Helpers/UrlHelper.html#method-i-link_to)
 is a helper that assists with generating links. It has a `:remote` option you
@@ -230,7 +218,7 @@ which generates
 <a href="/articles/1" data-remote="true">an article</a>
 ```
 
-You can bind to the same Ajax events as `form_for`. Here's an example. Let's
+You can bind to the same Ajax events as `form_with`. Here's an example. Let's
 assume that we have a list of articles that can be deleted with just one
 click. We would generate some HTML like this:
 
@@ -242,11 +230,11 @@ and write some CoffeeScript like this:
 
 ```coffeescript
 $ ->
-  $("a[data-remote]").on "ajax:success", (e, data, status, xhr) ->
+  $("a[data-remote]").on "ajax:success", (event) ->
     alert "The article was deleted."
 ```
 
-### button_to
+#### button_to
 
 [`button_to`](http://api.rubyonrails.org/classes/ActionView/Helpers/UrlHelper.html#method-i-button_to) is a helper that helps you create buttons. It has a `:remote` option that you can call like this:
 
@@ -262,7 +250,148 @@ this generates
 </form>
 ```
 
-Since it's just a `<form>`, all of the information on `form_for` also applies.
+Since it's just a `<form>`, all of the information on `form_with` also applies.
+
+### Customize remote elements
+
+It is possible to customize the behavior of elements with a `data-remote`
+attribute without writing a line of JavaScript. You can specify extra `data-`
+attributes to accomplish this.
+
+#### `data-method`
+
+Activating hyperlinks always results in an HTTP GET request. However, if your
+application is [RESTful](https://en.wikipedia.org/wiki/Representational_State_Transfer),
+some links are in fact actions that change data on the server, and must be
+performed with non-GET requests. This attribute allows marking up such links
+with an explicit method such as "post", "put" or "delete".
+
+The way it works is that, when the link is activated, it constructs a hidden form
+in the document with the "action" attribute corresponding to "href" value of the
+link, and the method corresponding to `data-method` value, and submits that form.
+
+NOTE: Because submitting forms with HTTP methods other than GET and POST isn't
+widely supported across browsers, all other HTTP methods are actually sent over
+POST with the intended method indicated in the `_method` parameter. Rails
+automatically detects and compensates for this.
+
+#### `data-url` and `data-params`
+
+Certain elements of your page aren't actually referring to any URL, but you may want
+them to trigger Ajax calls. Specifying the `data-url` attribute along with
+the `data-remote` one will trigger an Ajax call to the given URL. You can also
+specify extra parameters through the `data-params` attribute.
+
+This can be useful to trigger an action on check-boxes for instance:
+
+```html
+<input type="checkbox" data-remote="true"
+    data-url="/update" data-params="id=10" data-method="put">
+```
+
+#### `data-type`
+
+It is also possible to define the Ajax `dataType` explicitly while performing
+requests for `data-remote` elements, by way of the `data-type` attribute.
+
+### Confirmations
+
+You can ask for an extra confirmation of the user by adding a `data-confirm`
+attribute on links and forms. The user will be presented a JavaScript `confirm()`
+dialog containing the attribute's text. If the user chooses to cancel, the action
+doesn't take place.
+
+Adding this attribute on links will trigger the dialog on click, and adding it
+on forms will trigger it on submit. For example:
+
+```erb
+<%= link_to "Dangerous zone", dangerous_zone_path,
+  data: { confirm: 'Are you sure?' } %>
+```
+
+This generates:
+
+```html
+<a href="..." data-confirm="Are you sure?">Dangerous zone</a>
+```
+
+The attribute is also allowed on form submit buttons. This allows you to customize
+the warning message depending on the button which was activated. In this case,
+you should **not** have `data-confirm` on the form itself.
+
+The default confirmation uses a JavaScript confirm dialog, but you can customize
+this by listening to the `confirm` event, which is fired just before the confirmation
+window appears to the user. To cancel this default confirmation, have the confirm
+handler to return `false`.
+
+### Automatic disabling
+
+It is also possible to automatically disable an input while the form is submitting
+by using the `data-disable-with` attribute. This is to prevent accidental
+double-clicks from the user, which could result in duplicate HTTP requests that
+the backend may not detect as such. The value of the attribute is the text that will
+become the new value of the button in its disabled state.
+
+This also works for links with `data-method` attribute.
+
+For example:
+
+```erb
+<%= form_with(model: @article.new) do |f| %>
+  <%= f.submit data: { "disable-with": "Saving..." } %>
+<%= end %>
+```
+
+This generates a form with:
+
+```html
+<input data-disable-with="Saving..." type="submit">
+```
+
+### Rails-ujs event handlers
+
+Rails 5.1 introduced rails-ujs and dropped jQuery as a dependency.
+As a result the Unobtrusive JavaScript (UJS) driver has been rewritten to operate without jQuery.
+These introductions cause small changes to `custom events` fired during the request:
+
+NOTE: Signature of calls to UJS's event handlers has changed.
+Unlike the version with jQuery, all custom events return only one parameter: `event`.
+In this parameter, there is an additional attribute `detail` which contains an array of extra parameters.
+
+| Event name          | Extra parameters (event.detail) | Fired                                                       |
+|---------------------|---------------------------------|-------------------------------------------------------------|
+| `ajax:before`       |                                 | Before the whole ajax business.                             |
+| `ajax:beforeSend`   | [xhr, options]                  | Before the request is sent.                                 |
+| `ajax:send`         | [xhr]                           | When the request is sent.                                   |
+| `ajax:stopped`      |                                 | When the request is stopped.                                |
+| `ajax:success`      | [response, status, xhr]         | After completion, if the response was a success.            |
+| `ajax:error`        | [response, status, xhr]         | After completion, if the response was an error.             |
+| `ajax:complete`     | [xhr, status]                   | After the request has been completed, no matter the outcome.|
+
+Example usage:
+
+```html
+document.body.addEventListener('ajax:success', function(event) {
+  var detail = event.detail;
+  var data = detail[0], status = detail[1],  xhr = detail[2];
+})
+```
+
+NOTE: As of Rails 5.1 and the new `rails-ujs`, the parameters `data, status, xhr`
+have been bundled into `event.detail`. For information about the previously used
+`jquery-ujs` in Rails 5 and earlier, read the [`jquery-ujs` wiki](https://github.com/rails/jquery-ujs/wiki/ajax).
+
+### Stoppable events
+
+If you stop `ajax:before` or `ajax:beforeSend` by returning false from the
+handler method, the Ajax request will never take place. The `ajax:before` event
+can manipulate form data before serialization and the
+`ajax:beforeSend` event is useful for adding custom request headers.
+
+If you stop the `ajax:aborted:file` event, the default behavior of allowing the
+browser to submit the form via normal means (i.e. non-Ajax submission) will be
+canceled and the form will not be submitted at all. This is useful for
+implementing your own Ajax file upload workaround.
 
 Server-Side Concerns
 --------------------
@@ -297,7 +426,7 @@ The index view (`app/views/users/index.html.erb`) contains:
 
 <br>
 
-<%= form_for(@user, remote: true) do |f| %>
+<%= form_with(model: @user) do |f| %>
   <%= f.label :name %><br>
   <%= f.text_field :name %>
   <%= f.submit %>
@@ -338,7 +467,7 @@ this:
   end
 ```
 
-Notice the format.js in the `respond_to` block; that allows the controller to
+Notice the `format.js` in the `respond_to` block: that allows the controller to
 respond to your Ajax request. You then have a corresponding
 `app/views/users/create.js.erb` view file that generates the actual JavaScript
 code that will be sent and executed on the client side.
@@ -355,7 +484,7 @@ which uses Ajax to speed up page rendering in most applications.
 
 ### How Turbolinks Works
 
-Turbolinks attaches a click handler to all `<a>` on the page. If your browser
+Turbolinks attaches a click handler to all `<a>` tags on the page. If your browser
 supports
 [PushState](https://developer.mozilla.org/en-US/docs/Web/Guide/API/DOM/Manipulating_the_browser_history#The_pushState%28%29_method),
 Turbolinks will make an Ajax request for the page, parse the response, and
@@ -363,7 +492,7 @@ replace the entire `<body>` of the page with the `<body>` of the response. It
 will then use PushState to change the URL to the correct one, preserving
 refresh semantics and giving you pretty URLs.
 
-The only thing you have to do to enable Turbolinks is have it in your Gemfile,
+The only thing you have to do to enable Turbolinks is have it in your `Gemfile`,
 and put `//= require turbolinks` in your JavaScript manifest, which is usually
 `app/assets/javascripts/application.js`.
 
@@ -385,7 +514,7 @@ $(document).ready ->
 ```
 
 However, because Turbolinks overrides the normal page loading process, the
-event that this relies on will not be fired. If you have code that looks like
+event that this relies upon will not be fired. If you have code that looks like
 this, you must change your code to do this instead:
 
 ```coffeescript
diff --git a/guides/w3c_validator.rb b/guides/w3c_validator.rb
index 71f044b9c4..f38b6c2639 100644
--- a/guides/w3c_validator.rb
+++ b/guides/w3c_validator.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 # ---------------------------------------------------------------------------
 #
 # This script validates the generated guides against the W3C Validator.
@@ -21,19 +23,19 @@
 #
 #     Separate many using commas:
 #
-#       # validates only association_basics.html and migrations.html
-#       rake guides:validate ONLY=assoc,migrations
+#       # validates only association_basics.html and command_line.html
+#       rake guides:validate ONLY=assoc,command
 #
 # ---------------------------------------------------------------------------
 
-require 'w3c_validators'
+require "w3c_validators"
 include W3CValidators
 
 module RailsGuides
   class Validator
-
     def validate
-      validator = MarkupValidator.new
+      # https://github.com/w3c-validators/w3c_validators/issues/25
+      validator = NuValidator.new
       STDOUT.sync = true
       errors_on_guides = {}
 
@@ -45,11 +47,11 @@ module RailsGuides
           next
         end
 
-        if results.validity
-          print "."
-        else
+        if results.errors.length > 0
           print "E"
           errors_on_guides[f] = results.errors
+        else
+          print "."
         end
       end
 
@@ -57,40 +59,39 @@ module RailsGuides
     end
 
     private
-    def guides_to_validate
-      guides = Dir["./output/*.html"]
-      guides.delete("./output/layout.html")
-      guides.delete("./output/_license.html")
-      guides.delete("./output/_welcome.html")
-      ENV.key?('ONLY') ? select_only(guides) : guides
-    end
+      def guides_to_validate
+        guides = Dir["./output/*.html"]
+        guides.delete("./output/layout.html")
+        guides.delete("./output/_license.html")
+        guides.delete("./output/_welcome.html")
+        ENV.key?("ONLY") ? select_only(guides) : guides
+      end
 
-    def select_only(guides)
-      prefixes = ENV['ONLY'].split(",").map(&:strip)
-      guides.select do |guide|
-        prefixes.any? {|p| guide.start_with?("./output/#{p}")}
+      def select_only(guides)
+        prefixes = ENV["ONLY"].split(",").map(&:strip)
+        guides.select do |guide|
+          prefixes.any? { |p| guide.start_with?("./output/#{p}") }
+        end
       end
-    end
 
-    def show_results(error_list)
-      if error_list.size == 0
-        puts "\n\nAll checked guides validate OK!"
-      else
-        error_summary = error_detail = ""
+      def show_results(error_list)
+        if error_list.size == 0
+          puts "\n\nAll checked guides validate OK!"
+        else
+          error_summary = error_detail = ""
 
-        error_list.each_pair do |name, errors|
-          error_summary += "\n  #{name}"
-          error_detail += "\n\n  #{name} has #{errors.size} validation error(s):\n"
-          errors.each do |error|
-            error_detail += "\n    "+error.to_s.delete("\n")
+          error_list.each_pair do |name, errors|
+            error_summary += "\n  #{name}"
+            error_detail += "\n\n  #{name} has #{errors.size} validation error(s):\n"
+            errors.each do |error|
+              error_detail += "\n    " + error.to_s.delete("\n")
+            end
           end
-        end
 
-        puts "\n\nThere are #{error_list.size} guides with validation errors:\n" + error_summary
-        puts "\nHere are the detailed errors for each guide:" + error_detail
+          puts "\n\nThere are #{error_list.size} guides with validation errors:\n" + error_summary
+          puts "\nHere are the detailed errors for each guide:" + error_detail
+        end
       end
-    end
-
   end
 end
 
diff --git a/rails.gemspec b/rails.gemspec
index 8f9cc181a0..4b57377871 100644
--- a/rails.gemspec
+++ b/rails.gemspec
@@ -1,33 +1,36 @@
-version = File.read(File.expand_path('../RAILS_VERSION', __FILE__)).strip
+# frozen_string_literal: true
+
+version = File.read(File.expand_path("RAILS_VERSION", __dir__)).strip
 
 Gem::Specification.new do |s|
   s.platform    = Gem::Platform::RUBY
-  s.name        = 'rails'
+  s.name        = "rails"
   s.version     = version
-  s.summary     = 'Full-stack web application framework.'
-  s.description = 'Ruby on Rails is a full-stack web framework optimized for programmer happiness and sustainable productivity. It encourages beautiful code by favoring convention over configuration.'
+  s.summary     = "Full-stack web application framework."
+  s.description = "Ruby on Rails is a full-stack web framework optimized for programmer happiness and sustainable productivity. It encourages beautiful code by favoring convention over configuration."
 
-  s.required_ruby_version     = '>= 2.2.2'
-  s.required_rubygems_version = '>= 1.8.11'
+  s.required_ruby_version     = ">= 2.2.2"
+  s.required_rubygems_version = ">= 1.8.11"
 
-  s.license = 'MIT'
+  s.license = "MIT"
 
-  s.author   = 'David Heinemeier Hansson'
-  s.email    = 'david@loudthinking.com'
-  s.homepage = 'http://rubyonrails.org'
+  s.author   = "David Heinemeier Hansson"
+  s.email    = "david@loudthinking.com"
+  s.homepage = "http://rubyonrails.org"
 
-  s.files = ['README.md']
+  s.files = ["README.md"]
 
-  s.add_dependency 'activesupport', version
-  s.add_dependency 'actionpack',    version
-  s.add_dependency 'actionview',    version
-  s.add_dependency 'activemodel',   version
-  s.add_dependency 'activerecord',  version
-  s.add_dependency 'actionmailer',  version
-  s.add_dependency 'activejob',     version
-  s.add_dependency 'actioncable',   version
-  s.add_dependency 'railties',      version
+  s.add_dependency "activesupport", version
+  s.add_dependency "actionpack",    version
+  s.add_dependency "actionview",    version
+  s.add_dependency "activemodel",   version
+  s.add_dependency "activerecord",  version
+  s.add_dependency "actionmailer",  version
+  s.add_dependency "activejob",     version
+  s.add_dependency "actioncable",   version
+  s.add_dependency "activestorage", version
+  s.add_dependency "railties",      version
 
-  s.add_dependency 'bundler',         '>= 1.3.0', '< 2.0'
-  s.add_dependency 'sprockets-rails', '>= 2.0.0'
+  s.add_dependency "bundler",         ">= 1.3.0"
+  s.add_dependency "sprockets-rails", ">= 2.0.0"
 end
diff --git a/railties/CHANGELOG.md b/railties/CHANGELOG.md
index 982385438b..70c0f5c67b 100644
--- a/railties/CHANGELOG.md
+++ b/railties/CHANGELOG.md
@@ -1,9 +1,164 @@
-*   Ensure `/rails/info` routes match in development for apps with a catch-all globbing route.
+## Rails 5.2.0.beta2 (November 28, 2017) ##
 
-    *Nicholas Firth-McCoy*
+*   No changes.
 
-*   Added a shared section to `config/secrets.yml` that will be loaded for all environments.
 
-    *DHH*
+## Rails 5.2.0.beta1 (November 27, 2017) ##
 
-Please check [5-0-stable](https://github.com/rails/rails/blob/5-0-stable/railties/CHANGELOG.md) for previous changes.
+*   Deprecate `after_bundle` callback in Rails plugin templates.
+
+    *Yuji Yaginuma*
+
+*   `rails new` and `rails plugin new` get `Active Storage` by default.
+     Add ability to skip `Active Storage` with `--skip-active-storage`
+     and do so automatically when `--skip-active-record` is used.
+
+    *bogdanvlviv*
+
+*   Gemfile for new apps: upgrade redis-rb from ~> 3.0 to 4.0.
+
+    *Jeremy Daer*
+
+*   Add `mini_magick` to default `Gemfile` as comment.
+
+    *Yoshiyuki Hirano*
+
+*   Derive `secret_key_base` from the app name in development and test environments.
+
+    Spares away needless secret configs.
+
+    *DHH*, *Kasper Timm Hansen*
+
+*   Support multiple versions arguments for `gem` method of Generators.
+
+    *Yoshiyuki Hirano*
+
+*   Add `--skip-yarn` option to the plugin generator.
+
+    *bogdanvlviv*
+
+*   Optimize routes indentation.
+
+    *Yoshiyuki Hirano*
+
+*   Optimize indentation for generator actions.
+
+    *Yoshiyuki Hirano*
+
+*   Skip unused components when running `bin/rails` in Rails plugin.
+
+    *Yoshiyuki Hirano*
+
+*   Add `git_source` to `Gemfile` for plugin generator.
+
+    *Yoshiyuki Hirano*
+
+*   Add `--skip-action-cable` option to the plugin generator.
+
+    *bogdanvlviv*
+
+*   Deprecate support of use `Rails::Application` subclass to start Rails server.
+
+    *Yuji Yaginuma*
+
+*   Add `ruby x.x.x` version to `Gemfile` and create `.ruby-version`
+    root file containing the current Ruby version when new Rails applications are
+    created.
+
+    *Alberto Almagro*
+
+*   Support `-` as a platform-agnostic way to run a script from stdin with
+    `rails runner`
+
+    *Cody Cutrer*
+
+*   Add `bootsnap` to default `Gemfile`.
+
+    *Burke Libbey*
+
+*   Properly expand shortcuts for environment's name running the `console`
+    and `dbconsole` commands.
+
+    *Robin Dupret*
+
+*   Passing the environment's name as a regular argument to the
+    `rails dbconsole` and `rails console` commands is deprecated.
+    The `-e` option should be used instead.
+
+    Previously:
+
+        $ bin/rails dbconsole production
+
+    Now:
+
+        $ bin/rails dbconsole -e production
+
+    *Robin Dupret*, *Kasper Timm Hansen*
+
+*   Allow passing a custom connection name to the `rails dbconsole`
+    command when using a 3-level database configuration.
+
+        $ bin/rails dbconsole -c replica
+
+    *Robin Dupret*, *Jeremy Daer*
+
+*   Skip unused components when running `bin/rails app:update`.
+
+    If the initial app generation skipped Action Cable, Active Record etc.,
+    the update task honors those skips too.
+
+    *Yuji Yaginuma*
+
+*   Make Rails' test runner work better with minitest plugins.
+
+    By demoting the Rails test runner to just another minitest plugin —
+    and thereby not eager loading it — we can co-exist much better with
+    other minitest plugins such as pride and minitest-focus.
+
+    *Kasper Timm Hansen*
+
+*   Load environment file in `dbconsole` command.
+
+    Fixes #29717.
+
+    *Yuji Yaginuma*
+
+*   Add `rails secrets:show` command.
+
+    *Yuji Yaginuma*
+
+*   Allow mounting the same engine several times in different locations.
+
+    Fixes #20204.
+
+    *David Rodríguez*
+
+*   Clear screenshot files in `tmp:clear` task.
+
+    *Yuji Yaginuma*
+
+*   Add `railtie.rb` to the plugin generator
+
+    *Tsukuru Tanimichi*
+
+*   Deprecate `capify!` method in generators and templates.
+
+    *Yuji Yaginuma*
+
+*   Allow irb options to be passed from `rails console` command.
+
+    Fixes #28988.
+
+    *Yuji Yaginuma*
+
+*   Added a shared section to `config/database.yml` that will be loaded for all environments.
+
+    *Pierre Schambacher*
+
+*   Namespace error pages' CSS selectors to stop the styles from bleeding into other pages
+    when using Turbolinks.
+
+    *Jan Krutisch*
+
+
+Please check [5-1-stable](https://github.com/rails/rails/blob/5-1-stable/railties/CHANGELOG.md) for previous changes.
diff --git a/railties/MIT-LICENSE b/railties/MIT-LICENSE
index 1f496cf280..cce00cbc3a 100644
--- a/railties/MIT-LICENSE
+++ b/railties/MIT-LICENSE
@@ -1,4 +1,4 @@
-Copyright (c) 2004-2016 David Heinemeier Hansson
+Copyright (c) 2004-2018 David Heinemeier Hansson
 
 Permission is hereby granted, free of charge, to any person obtaining
 a copy of this software and associated documentation files (the
diff --git a/railties/RDOC_MAIN.rdoc b/railties/RDOC_MAIN.rdoc
index ef9bbf3d7e..c70a9f0ba0 100644
--- a/railties/RDOC_MAIN.rdoc
+++ b/railties/RDOC_MAIN.rdoc
@@ -1,35 +1,50 @@
 == Welcome to \Rails
 
-\Rails is a web-application framework that includes everything needed to create
-database-backed web applications according to the {Model-View-Controller (MVC)}[http://en.wikipedia.org/wiki/Model-view-controller] pattern.
-
-Understanding the MVC pattern is key to understanding \Rails. MVC divides your application
-into three layers, each with a specific responsibility.
-
-The View layer is composed of "templates" that are responsible for providing
-appropriate representations of your application's resources. Templates
-can come in a variety of formats, but most view templates are \HTML with embedded Ruby
-code (.erb files).
-
-The Model layer represents your domain model (such as Account, Product, Person, Post)
-and encapsulates the business logic that is specific to your application. In \Rails,
-database-backed model classes are derived from ActiveRecord::Base. Active Record allows
-you to present the data from database rows as objects and embellish these data objects
-with business logic methods. Although most \Rails models are backed by a database, models
-can also be ordinary Ruby classes, or Ruby classes that implement a set of interfaces as
-provided by the ActiveModel module. You can read more about Active Record in its
-{README}[link:files/activerecord/README_rdoc.html].
-
-The Controller layer is responsible for handling incoming HTTP requests and providing a
-suitable response. Usually this means returning \HTML, but \Rails controllers can also
-generate XML, JSON, PDFs, mobile-specific views, and more. Controllers manipulate models
-and render view templates in order to generate the appropriate HTTP response.
-
-In \Rails, the Controller and View layers are handled together by Action Pack.
-These two layers are bundled in a single package due to their heavy interdependence.
-This is unlike the relationship between Active Record and Action Pack, which are
-independent. Each of these packages can be used independently outside of \Rails. You
-can read more about Action Pack in its {README}[link:files/actionpack/README_rdoc.html].
+\Rails is a web-application framework that includes everything needed to
+create database-backed web applications according to the
+{Model-View-Controller (MVC)}[http://en.wikipedia.org/wiki/Model-view-controller]
+pattern.
+
+Understanding the MVC pattern is key to understanding \Rails. MVC divides your
+application into three layers, each with a specific responsibility.
+
+The <em>Model layer</em> represents your domain model (such as Account, Product,
+Person, Post, etc.) and encapsulates the business logic that is specific to
+your application. In \Rails, database-backed model classes are derived from
+ActiveRecord::Base. Active Record allows you to present the data from
+database rows as objects and embellish these data objects with business logic
+methods. You can read more about Active Record in its {README}[link:files/activerecord/README_rdoc.html].
+Although most \Rails models are backed by a database, models can also be ordinary
+Ruby classes, or Ruby classes that implement a set of interfaces as provided by
+the Active Model module. You can read more about Active Model in its {README}[link:files/activemodel/README_rdoc.html].
+
+The <em>Controller layer</em> is responsible for handling incoming HTTP requests and
+providing a suitable response. Usually this means returning \HTML, but \Rails controllers
+can also generate XML, JSON, PDFs, mobile-specific views, and more. Controllers load and
+manipulate models, and render view templates in order to generate the appropriate HTTP response.
+In \Rails, incoming requests are routed by Action Dispatch to an appropriate controller, and
+controller classes are derived from ActionController::Base. Action Dispatch and Action Controller
+are bundled together in Action Pack. You can read more about Action Pack in its
+{README}[link:files/actionpack/README_rdoc.html].
+
+The <em>View layer</em> is composed of "templates" that are responsible for providing
+appropriate representations of your application's resources. Templates can
+come in a variety of formats, but most view templates are \HTML with embedded
+Ruby code (ERB files). Views are typically rendered to generate a controller response,
+or to generate the body of an email. In \Rails, View generation is handled by Action View.
+You can read more about Action View in its {README}[link:files/actionview/README_rdoc.html].
+
+Active Record, Active Model, Action Pack, and Action View can each be used independently outside \Rails.
+In addition to that, \Rails also comes with Action Mailer ({README}[link:files/actionmailer/README_rdoc.html]), a library
+to generate and send emails; Active Job ({README}[link:files/activejob/README_md.html]), a
+framework for declaring jobs and making them run on a variety of queueing
+backends; Action Cable ({README}[link:files/actioncable/README_md.html]), a framework to
+integrate WebSockets with a \Rails application;
+Active Storage ({README}[link:files/activestorage/README_md.html]), a library to attach cloud
+and local files to \Rails applications;
+and Active Support ({README}[link:files/activesupport/README_rdoc.html]), a collection
+of utility classes and standard library extensions that are useful for \Rails,
+and may also be used independently outside \Rails.
 
 == Getting Started
 
@@ -45,29 +60,32 @@ can read more about Action Pack in its {README}[link:files/actionpack/README_rdo
 
 3. Change directory to +myapp+ and start the web server:
 
-    $ cd myapp; rails server
+    $ cd myapp
+    $ rails server
 
    Run with <tt>--help</tt> or <tt>-h</tt> for options.
 
-4. Go to http://localhost:3000 and you'll see:
-
-    "Yay! You’re on Rails!"
+4. Go to <tt>http://localhost:3000</tt> and you'll see: "Yay! You’re on \Rails!"
 
 5. Follow the guidelines to start developing your application. You may find the following resources handy:
 
-* The \README file created within your application.
-* {Getting Started with \Rails}[http://guides.rubyonrails.org/getting_started.html].
-* {Ruby on \Rails Tutorial}[http://www.railstutorial.org/book].
-* {Ruby on \Rails Guides}[http://guides.rubyonrails.org].
-* {The API Documentation}[http://api.rubyonrails.org].
+   * The \README file created within your application.
+   * {Getting Started with \Rails}[http://guides.rubyonrails.org/getting_started.html].
+   * {Ruby on \Rails Guides}[http://guides.rubyonrails.org].
+   * {The API Documentation}[http://api.rubyonrails.org].
+   * {Ruby on \Rails Tutorial}[https://www.railstutorial.org/book].
 
 == Contributing
 
-We encourage you to contribute to Ruby on \Rails! Please check out the {Contributing to Rails
-guide}[http://edgeguides.rubyonrails.org/contributing_to_ruby_on_rails.html] for guidelines about how
-to proceed. {Join us}[http://contributors.rubyonrails.org]!
+We encourage you to contribute to Ruby on \Rails! Please check out the
+{Contributing to Ruby on \Rails guide}[http://guides.rubyonrails.org/contributing_to_ruby_on_rails.html] for guidelines about how to proceed. {Join us!}[http://contributors.rubyonrails.org]
+
+Trying to report a possible security vulnerability in \Rails? Please
+check out our {security policy}[http://rubyonrails.org/security/] for
+guidelines about how to proceed.
 
+Everyone interacting in \Rails and its sub-projects' codebases, issue trackers, chat rooms, and mailing lists is expected to follow the \Rails {code of conduct}[http://rubyonrails.org/conduct/].
 
 == License
 
-Ruby on \Rails is released under the {MIT License}[http://www.opensource.org/licenses/MIT].
+Ruby on \Rails is released under the {MIT License}[https://opensource.org/licenses/MIT].
diff --git a/railties/README.rdoc b/railties/README.rdoc
index a25658668c..2715ccac3f 100644
--- a/railties/README.rdoc
+++ b/railties/README.rdoc
@@ -23,7 +23,7 @@ Source code can be downloaded as part of the Rails project on GitHub
 
 Railties is released under the MIT license:
 
-* http://www.opensource.org/licenses/MIT
+* https://opensource.org/licenses/MIT
 
 == Support
 
@@ -38,4 +38,3 @@ Bug reports can be filed for the Ruby on Rails project here:
 Feature requests should be discussed on the rails-core mailing list here:
 
 * https://groups.google.com/forum/?fromgroups#!forum/rubyonrails-core
-
diff --git a/railties/Rakefile b/railties/Rakefile
index db23bbabaa..74615d2358 100644
--- a/railties/Rakefile
+++ b/railties/Rakefile
@@ -1,33 +1,78 @@
-require 'rake/testtask'
+# frozen_string_literal: true
 
-task :default => :test
+require "rake/testtask"
+
+task default: :test
 
 task :package
 
 desc "Run all unit tests"
-task :test => 'test:isolated'
+task test: "test:isolated"
 
 namespace :test do
   task :isolated do
+    dash_i = [
+      "test",
+      "lib",
+      "../activesupport/lib",
+      "../actionpack/lib",
+      "../actionview/lib",
+      "../activemodel/lib"
+    ].map { |dir| File.expand_path(dir, __dir__) }
+
+    dash_i.reverse_each do |x|
+      $:.unshift(x) unless $:.include?(x)
+    end
+    $-w = true
+
+    require "bundler/setup" unless defined?(Bundler)
+    require "active_support"
+
+    failing_files = []
+
     dirs = (ENV["TEST_DIR"] || ENV["TEST_DIRS"] || "**").split(",")
     test_files = dirs.map { |dir| "test/#{dir}/*_test.rb" }
     Dir[*test_files].each do |file|
-      next true if file.include?("fixtures")
-      dash_i = [
-        'test',
-        'lib',
-        "#{File.dirname(__FILE__)}/../activesupport/lib",
-        "#{File.dirname(__FILE__)}/../actionpack/lib",
-        "#{File.dirname(__FILE__)}/../activemodel/lib"
-      ]
-      ruby "-w", "-I#{dash_i.join ':'}", file
+      next true if file.start_with?("test/fixtures/")
+
+      fake_command = Shellwords.join([
+        FileUtils::RUBY,
+        "-w",
+        *dash_i.map { |dir| "-I#{Pathname.new(dir).relative_path_from(Pathname.pwd)}" },
+        file,
+      ])
+      puts fake_command
+
+      # We could run these in parallel, but pretty much all of the
+      # railties tests already run in parallel, so ¯\_(⊙︿⊙)_/¯
+      Process.waitpid fork {
+        ARGV.clear
+        Rake.application = nil
+
+        load file
+      }
+
+      unless $?.success?
+        failing_files << file
+      end
+    end
+
+    unless failing_files.empty?
+      puts
+      puts "Failed in:"
+      failing_files.each do |file|
+        puts "  #{file}"
+      end
+      puts
+
+      raise "Failure in isolated test runner"
     end
   end
 end
 
-Rake::TestTask.new('test:regular') do |t|
-  t.libs << 'test' << "#{File.dirname(__FILE__)}/../activesupport/lib"
-  t.pattern = 'test/**/*_test.rb'
+Rake::TestTask.new("test:regular") do |t|
+  t.libs << "test" << "#{__dir__}/../activesupport/lib"
+  t.pattern = "test/**/*_test.rb"
   t.warning = false
   t.verbose = true
   t.ruby_opts = ["--dev"] if defined?(JRUBY_VERSION)
diff --git a/railties/bin/test b/railties/bin/test
new file mode 100755
index 0000000000..c53377cc97
--- /dev/null
+++ b/railties/bin/test
@@ -0,0 +1,5 @@
+#!/usr/bin/env ruby
+# frozen_string_literal: true
+
+COMPONENT_ROOT = File.expand_path("..", __dir__)
+require_relative "../../tools/test"
diff --git a/railties/exe/rails b/railties/exe/rails
index 82c17cabce..79af4db6b6 100755
--- a/railties/exe/rails
+++ b/railties/exe/rails
@@ -1,9 +1,10 @@
 #!/usr/bin/env ruby
+# frozen_string_literal: true
 
-git_path = File.expand_path('../../../.git', __FILE__)
+git_path = File.expand_path("../../.git", __dir__)
 
 if File.exist?(git_path)
-  railties_path = File.expand_path('../../lib', __FILE__)
+  railties_path = File.expand_path("../lib", __dir__)
   $:.unshift(railties_path)
 end
 require "rails/cli"
diff --git a/railties/lib/minitest/rails_plugin.rb b/railties/lib/minitest/rails_plugin.rb
new file mode 100644
index 0000000000..6901b0bbc8
--- /dev/null
+++ b/railties/lib/minitest/rails_plugin.rb
@@ -0,0 +1,54 @@
+# frozen_string_literal: true
+
+require "active_support/core_ext/module/attribute_accessors"
+require "rails/test_unit/reporter"
+require "rails/test_unit/runner"
+
+module Minitest
+  class SuppressedSummaryReporter < SummaryReporter
+    # Disable extra failure output after a run if output is inline.
+    def aggregated_results(*)
+      super unless options[:output_inline]
+    end
+  end
+
+  def self.plugin_rails_options(opts, options)
+    Rails::TestUnit::Runner.attach_before_load_options(opts)
+
+    opts.on("-b", "--backtrace", "Show the complete backtrace") do
+      options[:full_backtrace] = true
+    end
+
+    opts.on("-d", "--defer-output", "Output test failures and errors after the test run") do
+      options[:output_inline] = false
+    end
+
+    opts.on("-f", "--fail-fast", "Abort test run on first failure or error") do
+      options[:fail_fast] = true
+    end
+
+    opts.on("-c", "--[no-]color", "Enable color in the output") do |value|
+      options[:color] = value
+    end
+
+    options[:color] = true
+    options[:output_inline] = true
+  end
+
+  # Owes great inspiration to test runner trailblazers like RSpec,
+  # minitest-reporters, maxitest and others.
+  def self.plugin_rails_init(options)
+    unless options[:full_backtrace] || ENV["BACKTRACE"]
+      # Plugin can run without Rails loaded, check before filtering.
+      Minitest.backtrace_filter = ::Rails.backtrace_cleaner if ::Rails.respond_to?(:backtrace_cleaner)
+    end
+
+    # Replace progress reporter for colors.
+    reporter.reporters.delete_if { |reporter| reporter.kind_of?(SummaryReporter) || reporter.kind_of?(ProgressReporter) }
+    reporter << SuppressedSummaryReporter.new(options[:io], options)
+    reporter << ::Rails::TestUnitReporter.new(options[:io], options)
+  end
+
+  # Backwardscompatibility with Rails 5.0 generated plugin test scripts
+  mattr_reader :run_via, default: {}
+end
diff --git a/railties/lib/rails.rb b/railties/lib/rails.rb
index fe789f3c2a..092105d502 100644
--- a/railties/lib/rails.rb
+++ b/railties/lib/rails.rb
@@ -1,18 +1,21 @@
-require 'rails/ruby_version_check'
+# frozen_string_literal: true
 
-require 'pathname'
+require "rails/ruby_version_check"
 
-require 'active_support'
-require 'active_support/dependencies/autoload'
-require 'active_support/core_ext/kernel/reporting'
-require 'active_support/core_ext/module/delegation'
-require 'active_support/core_ext/array/extract_options'
+require "pathname"
 
-require 'rails/application'
-require 'rails/version'
+require "active_support"
+require "active_support/dependencies/autoload"
+require "active_support/core_ext/kernel/reporting"
+require "active_support/core_ext/module/delegation"
+require "active_support/core_ext/array/extract_options"
+require "active_support/core_ext/object/blank"
 
-require 'active_support/railtie'
-require 'action_dispatch/railtie'
+require "rails/application"
+require "rails/version"
+
+require "active_support/railtie"
+require "action_dispatch/railtie"
 
 # UTF-8 is the default internal and external encoding.
 silence_warnings do
@@ -46,14 +49,14 @@ module Rails
 
     def backtrace_cleaner
       @backtrace_cleaner ||= begin
-        # Relies on Active Support, so we have to lazy load to postpone definition until AS has been loaded
-        require 'rails/backtrace_cleaner'
+        # Relies on Active Support, so we have to lazy load to postpone definition until Active Support has been loaded
+        require "rails/backtrace_cleaner"
         Rails::BacktraceCleaner.new
       end
     end
 
-    # Returns a Pathname object of the current rails project,
-    # otherwise it returns nil if there is no project:
+    # Returns a Pathname object of the current Rails project,
+    # otherwise it returns +nil+ if there is no project:
     #
     #   Rails.root
     #     # => #<Pathname:/Users/someuser/some/path/project>
@@ -67,7 +70,7 @@ module Rails
     #   Rails.env.development? # => true
     #   Rails.env.production? # => false
     def env
-      @_env ||= ActiveSupport::StringInquirer.new(ENV["RAILS_ENV"] || ENV["RACK_ENV"] || "development")
+      @_env ||= ActiveSupport::StringInquirer.new(ENV["RAILS_ENV"].presence || ENV["RACK_ENV"].presence || "development")
     end
 
     # Sets the Rails environment.
@@ -77,7 +80,7 @@ module Rails
       @_env = ActiveSupport::StringInquirer.new(environment)
     end
 
-    # Returns all rails groups for loading based on:
+    # Returns all Rails groups for loading based on:
     #
     # * The Rails environment;
     # * The environment variable RAILS_GROUPS;
@@ -86,8 +89,8 @@ module Rails
     #   groups assets: [:development, :test]
     #
     #   # Returns
-    #   # => [:default, :development, :assets] for Rails.env == "development"
-    #   # => [:default, :production]           for Rails.env == "production"
+    #   # => [:default, "development", :assets] for Rails.env == "development"
+    #   # => [:default, "production"]           for Rails.env == "production"
     def groups(*groups)
       hash = groups.extract_options!
       env = Rails.env
@@ -100,7 +103,7 @@ module Rails
     end
 
     # Returns a Pathname object of the public folder of the current
-    # rails project, otherwise it returns nil if there is no project:
+    # Rails project, otherwise it returns +nil+ if there is no project:
     #
     #   Rails.public_path
     #     # => #<Pathname:/Users/someuser/some/path/project/public>
diff --git a/railties/lib/rails/all.rb b/railties/lib/rails/all.rb
index 1a7f7855f1..f5dccd2381 100644
--- a/railties/lib/rails/all.rb
+++ b/railties/lib/rails/all.rb
@@ -1,7 +1,10 @@
-require 'rails'
+# frozen_string_literal: true
+
+require "rails"
 
 %w(
   active_record/railtie
+  active_storage/engine
   action_controller/railtie
   action_view/railtie
   action_mailer/railtie
diff --git a/railties/lib/rails/api/generator.rb b/railties/lib/rails/api/generator.rb
new file mode 100644
index 0000000000..3405560b74
--- /dev/null
+++ b/railties/lib/rails/api/generator.rb
@@ -0,0 +1,37 @@
+# frozen_string_literal: true
+
+require "sdoc"
+
+class RDoc::Generator::API < RDoc::Generator::SDoc # :nodoc:
+  RDoc::RDoc.add_generator self
+
+  def generate_class_tree_level(classes, visited = {})
+    # Only process core extensions on the first visit and remove
+    # Active Storage duplicated classes that are at the top level
+    # since they aren't nested under a definition of the `ActiveStorage` module.
+    if visited.empty?
+      classes = classes.reject { |klass| active_storage?(klass) }
+      core_exts, classes = classes.partition { |klass| core_extension?(klass) }
+
+      super.unshift([ "Core extensions", "", "", build_core_ext_subtree(core_exts, visited) ])
+    else
+      super
+    end
+  end
+
+  private
+    def build_core_ext_subtree(classes, visited)
+      classes.map do |klass|
+        [ klass.name, klass.document_self_or_methods ? klass.path : "", "",
+            generate_class_tree_level(klass.classes_and_modules, visited) ]
+      end
+    end
+
+    def core_extension?(klass)
+      klass.name != "ActiveSupport" && klass.in_files.any? { |file| file.absolute_name.include?("core_ext") }
+    end
+
+    def active_storage?(klass)
+      klass.name != "ActiveStorage" && klass.in_files.all? { |file| file.absolute_name.include?("active_storage") }
+    end
+end
diff --git a/railties/lib/rails/api/task.rb b/railties/lib/rails/api/task.rb
index d478bbf9e8..e7f0557584 100644
--- a/railties/lib/rails/api/task.rb
+++ b/railties/lib/rails/api/task.rb
@@ -1,33 +1,35 @@
-require 'rdoc/task'
+# frozen_string_literal: true
+
+require "rdoc/task"
+require "rails/api/generator"
 
 module Rails
   module API
     class Task < RDoc::Task
       RDOC_FILES = {
-        'activesupport' => {
-          :include => %w(
+        "activesupport" => {
+          include: %w(
             README.rdoc
             lib/active_support/**/*.rb
-          ),
-          :exclude => 'lib/active_support/vendor/*'
+          )
         },
 
-        'activerecord' => {
-          :include => %w(
+        "activerecord" => {
+          include: %w(
             README.rdoc
             lib/active_record/**/*.rb
           )
         },
 
-        'activemodel' => {
-          :include => %w(
+        "activemodel" => {
+          include: %w(
             README.rdoc
             lib/active_model/**/*.rb
           )
         },
 
-        'actionpack' => {
-          :include => %w(
+        "actionpack" => {
+          include: %w(
             README.rdoc
             lib/abstract_controller/**/*.rb
             lib/action_controller/**/*.rb
@@ -35,41 +37,53 @@ module Rails
           )
         },
 
-        'actionview' => {
-          :include => %w(
+        "actionview" => {
+          include: %w(
             README.rdoc
             lib/action_view/**/*.rb
           ),
-          :exclude => 'lib/action_view/vendor/*'
+          exclude: "lib/action_view/vendor/*"
         },
 
-        'actionmailer' => {
-          :include => %w(
+        "actionmailer" => {
+          include: %w(
             README.rdoc
             lib/action_mailer/**/*.rb
           )
         },
 
-        'activejob' => {
-          :include => %w(
+        "activejob" => {
+          include: %w(
             README.md
             lib/active_job/**/*.rb
           )
         },
 
-        'actioncable' => {
-          :include => %w(
+        "actioncable" => {
+          include: %w(
             README.md
             lib/action_cable/**/*.rb
           )
         },
 
-        'railties' => {
-          :include => %w(
+        "activestorage" => {
+          include: %w(
+            README.md
+            app/**/active_storage/**/*.rb
+            lib/active_storage/**/*.rb
+          )
+        },
+
+        "railties" => {
+          include: %w(
             README.rdoc
             lib/**/*.rb
           ),
-          :exclude => 'lib/rails/generators/rails/**/templates/**/*.rb'
+          exclude: %w(
+            lib/rails/generators/**/templates/**/*.rb
+            lib/rails/test_unit/*
+            lib/rails/api/generator.rb
+          )
         }
       }
 
@@ -80,7 +94,7 @@ module Rails
         # Be lazy computing stuff to have as light impact as possible to
         # the rest of tasks.
         before_running_rdoc do
-          load_and_configure_sdoc
+          configure_sdoc
           configure_rdoc_files
           setup_horo_variables
         end
@@ -91,20 +105,15 @@ module Rails
         # no-op
       end
 
-      def load_and_configure_sdoc
-        require 'sdoc'
-
-        self.title    = 'Ruby on Rails API'
+      def configure_sdoc
+        self.title    = "Ruby on Rails API"
         self.rdoc_dir = api_dir
 
-        options << '-m'  << api_main
-        options << '-e'  << 'UTF-8'
+        options << "-m"  << api_main
+        options << "-e"  << "UTF-8"
 
-        options << '-f'  << 'sdoc'
-        options << '-T'  << 'rails'
-      rescue LoadError
-        $stderr.puts %(Unable to load SDoc, please add\n\n    gem 'sdoc', require: false\n\nto the Gemfile.)
-        exit 1
+        options << "-f"  << "api"
+        options << "-T"  << "rails"
       end
 
       def configure_rdoc_files
@@ -121,22 +130,35 @@ module Rails
             rdoc_files.exclude("#{cdr}/#{pattern}")
           end
         end
+
+        # Only generate documentation for files that have been
+        # changed since the API was generated.
+        if Dir.exist?("doc/rdoc") && !ENV["ALL"]
+          last_generation = DateTime.rfc2822(File.open("doc/rdoc/created.rid", &:readline))
+
+          rdoc_files.keep_if do |file|
+            File.mtime(file).to_datetime > last_generation
+          end
+
+          # Nothing to do
+          exit(0) if rdoc_files.empty?
+        end
       end
 
       def setup_horo_variables
-        ENV['HORO_PROJECT_NAME']    = 'Ruby on Rails'
-        ENV['HORO_PROJECT_VERSION'] = rails_version
+        ENV["HORO_PROJECT_NAME"]    = "Ruby on Rails"
+        ENV["HORO_PROJECT_VERSION"] = rails_version
       end
 
       def api_main
-        component_root_dir('railties') + '/RDOC_MAIN.rdoc'
+        component_root_dir("railties") + "/RDOC_MAIN.rdoc"
       end
     end
 
     class RepoTask < Task
-      def load_and_configure_sdoc
+      def configure_sdoc
         super
-        options << '-g' # link to GitHub, SDoc flag
+        options << "-g" # link to GitHub, SDoc flag
       end
 
       def component_root_dir(component)
@@ -144,7 +166,7 @@ module Rails
       end
 
       def api_dir
-        'doc/rdoc'
+        "doc/rdoc"
       end
     end
 
@@ -156,7 +178,7 @@ module Rails
 
     class StableTask < RepoTask
       def rails_version
-        File.read('RAILS_VERSION').strip
+        File.read("RAILS_VERSION").strip
       end
     end
   end
diff --git a/railties/lib/rails/app_loader.rb b/railties/lib/rails/app_loader.rb
index af004d85bf..20eb75d95c 100644
--- a/railties/lib/rails/app_loader.rb
+++ b/railties/lib/rails/app_loader.rb
@@ -1,22 +1,35 @@
-require 'pathname'
-require 'rails/version'
+# frozen_string_literal: true
+
+require "pathname"
+require "rails/version"
 
 module Rails
   module AppLoader # :nodoc:
     extend self
 
     RUBY = Gem.ruby
-    EXECUTABLES = ['bin/rails', 'script/rails']
+    EXECUTABLES = ["bin/rails", "script/rails"]
     BUNDLER_WARNING = <<EOS
-Looks like your app's ./bin/rails is a stub that was generated by Bundler.
+Beginning in Rails 4, Rails ships with a `rails` binstub at ./bin/rails that
+should be used instead of the Bundler-generated `rails` binstub.
+
+If you are seeing this message, your binstub at ./bin/rails was generated by
+Bundler instead of Rails.
+
+You might need to regenerate your `rails` binstub locally and add it to source
+control:
+
+ rails app:update:bin           # Bear in mind this generates other binstubs
+                                # too that you may or may not want (like yarn)
 
-In Rails #{Rails::VERSION::MAJOR}, your app's bin/ directory contains executables that are versioned
-like any other source code, rather than stubs that are generated on demand.
+If you already have Rails binstubs in source control, you might be
+inadverently overwriting them during deployment by using bundle install
+with the --binstubs option.
 
-Here's how to upgrade:
+If your application was created prior to Rails 4, here's how to upgrade:
 
   bundle config --delete bin    # Turn off Bundler's stub generator
-  rails app:update:bin          # Use the new Rails 5 executables
+  rails app:update:bin          # Use the new Rails executables
   git add bin                   # Add bin/ to source control
 
 You may need to remove bin/ from your .gitignore as well.
@@ -39,21 +52,21 @@ EOS
           if contents =~ /(APP|ENGINE)_PATH/
             exec RUBY, exe, *ARGV
             break # non reachable, hack to be able to stub exec in the test suite
-          elsif exe.end_with?('bin/rails') && contents.include?('This file was generated by Bundler')
+          elsif exe.end_with?("bin/rails") && contents.include?("This file was generated by Bundler")
             $stderr.puts(BUNDLER_WARNING)
-            Object.const_set(:APP_PATH, File.expand_path('config/application', Dir.pwd))
-            require File.expand_path('../boot', APP_PATH)
-            require 'rails/commands'
+            Object.const_set(:APP_PATH, File.expand_path("config/application", Dir.pwd))
+            require File.expand_path("../boot", APP_PATH)
+            require "rails/commands"
             break
           end
         end
 
         # If we exhaust the search there is no executable, this could be a
         # call to generate a new application, so restore the original cwd.
-        Dir.chdir(original_cwd) and return if Pathname.new(Dir.pwd).root?
+        Dir.chdir(original_cwd) && return if Pathname.new(Dir.pwd).root?
 
         # Otherwise keep moving upwards in search of an executable.
-        Dir.chdir('..')
+        Dir.chdir("..")
       end
     end
 
diff --git a/railties/lib/rails/app_updater.rb b/railties/lib/rails/app_updater.rb
new file mode 100644
index 0000000000..a076d082d5
--- /dev/null
+++ b/railties/lib/rails/app_updater.rb
@@ -0,0 +1,34 @@
+# frozen_string_literal: true
+
+require "rails/generators"
+require "rails/generators/rails/app/app_generator"
+
+module Rails
+  class AppUpdater # :nodoc:
+    class << self
+      def invoke_from_app_generator(method)
+        app_generator.send(method)
+      end
+
+      def app_generator
+        @app_generator ||= begin
+          gen = Rails::Generators::AppGenerator.new ["rails"], generator_options, destination_root: Rails.root
+          File.exist?(Rails.root.join("config", "application.rb")) ? gen.send(:app_const) : gen.send(:valid_const?)
+          gen
+        end
+      end
+
+      private
+        def generator_options
+          options = { api: !!Rails.application.config.api_only, update: true }
+          options[:skip_active_record]  = !defined?(ActiveRecord::Railtie)
+          options[:skip_active_storage] = !defined?(ActiveStorage::Engine) || !defined?(ActiveRecord::Railtie)
+          options[:skip_action_mailer]  = !defined?(ActionMailer::Railtie)
+          options[:skip_action_cable]   = !defined?(ActionCable::Engine)
+          options[:skip_sprockets]      = !defined?(Sprockets::Railtie)
+          options[:skip_puma]           = !defined?(Puma)
+          options
+        end
+    end
+  end
+end
diff --git a/railties/lib/rails/application.rb b/railties/lib/rails/application.rb
index c383de3e06..a200a1005c 100644
--- a/railties/lib/rails/application.rb
+++ b/railties/lib/rails/application.rb
@@ -1,9 +1,14 @@
-require 'yaml'
-require 'active_support/core_ext/hash/keys'
-require 'active_support/core_ext/object/blank'
-require 'active_support/key_generator'
-require 'active_support/message_verifier'
-require 'rails/engine'
+# frozen_string_literal: true
+
+require "yaml"
+require "active_support/core_ext/hash/keys"
+require "active_support/core_ext/object/blank"
+require "active_support/key_generator"
+require "active_support/message_verifier"
+require "active_support/encrypted_configuration"
+require "active_support/deprecation"
+require "rails/engine"
+require "rails/secrets"
 
 module Rails
   # An Engine with the responsibility of coordinating the whole boot process.
@@ -72,21 +77,22 @@ module Rails
   # on one of the applications to create a copy of the application which shares
   # the configuration.
   #
-  # If you decide to define rake tasks, runners, or initializers in an
+  # If you decide to define Rake tasks, runners, or initializers in an
   # application other than +Rails.application+, then you must run them manually.
   class Application < Engine
-    autoload :Bootstrap,              'rails/application/bootstrap'
-    autoload :Configuration,          'rails/application/configuration'
-    autoload :DefaultMiddlewareStack, 'rails/application/default_middleware_stack'
-    autoload :Finisher,               'rails/application/finisher'
-    autoload :Railties,               'rails/engine/railties'
-    autoload :RoutesReloader,         'rails/application/routes_reloader'
+    autoload :Bootstrap,              "rails/application/bootstrap"
+    autoload :Configuration,          "rails/application/configuration"
+    autoload :DefaultMiddlewareStack, "rails/application/default_middleware_stack"
+    autoload :Finisher,               "rails/application/finisher"
+    autoload :Railties,               "rails/engine/railties"
+    autoload :RoutesReloader,         "rails/application/routes_reloader"
 
     class << self
       def inherited(base)
         super
         Rails.app_class = base
         add_lib_to_load_path!(find_root(base.called_from))
+        ActiveSupport.run_load_hooks(:before_configuration, base)
       end
 
       def instance
@@ -146,7 +152,6 @@ module Rails
     def run_load_hooks! # :nodoc:
       return self if @ran_load_hooks
       @ran_load_hooks = true
-      ActiveSupport.run_load_hooks(:before_configuration, self)
 
       @initial_variable_values.each do |variable_name, value|
         if INITIAL_VARIABLES.include?(variable_name)
@@ -168,12 +173,10 @@ module Rails
       # number of iterations selected based on consultation with the google security
       # team. Details at https://github.com/rails/rails/pull/6952#issuecomment-7661220
       @caching_key_generator ||=
-        if secrets.secret_key_base
-          unless secrets.secret_key_base.kind_of?(String)
-            raise ArgumentError, "`secret_key_base` for #{Rails.env} environment must be a type of String, change this value in `config/secrets.yml`"
-          end
-          key_generator = ActiveSupport::KeyGenerator.new(secrets.secret_key_base, iterations: 1000)
-          ActiveSupport::CachingKeyGenerator.new(key_generator)
+        if secret_key_base
+          ActiveSupport::CachingKeyGenerator.new(
+            ActiveSupport::KeyGenerator.new(secret_key_base, iterations: 1000)
+          )
         else
           ActiveSupport::LegacyKeyGenerator.new(secrets.secret_token)
         end
@@ -243,13 +246,11 @@ module Rails
     # will be used by middlewares and engines to configure themselves.
     def env_config
       @app_env_config ||= begin
-        validate_secret_key_config!
-
         super.merge(
           "action_dispatch.parameter_filter" => config.filter_parameters,
           "action_dispatch.redirect_filter" => config.filter_redirect,
           "action_dispatch.secret_token" => secrets.secret_token,
-          "action_dispatch.secret_key_base" => secrets.secret_key_base,
+          "action_dispatch.secret_key_base" => secret_key_base,
           "action_dispatch.show_exceptions" => config.action_dispatch.show_exceptions,
           "action_dispatch.show_detailed_exceptions" => config.consider_all_requests_local,
           "action_dispatch.logger" => Rails.logger,
@@ -259,14 +260,21 @@ module Rails
           "action_dispatch.signed_cookie_salt" => config.action_dispatch.signed_cookie_salt,
           "action_dispatch.encrypted_cookie_salt" => config.action_dispatch.encrypted_cookie_salt,
           "action_dispatch.encrypted_signed_cookie_salt" => config.action_dispatch.encrypted_signed_cookie_salt,
+          "action_dispatch.authenticated_encrypted_cookie_salt" => config.action_dispatch.authenticated_encrypted_cookie_salt,
+          "action_dispatch.use_authenticated_cookie_encryption" => config.action_dispatch.use_authenticated_cookie_encryption,
+          "action_dispatch.encrypted_cookie_cipher" => config.action_dispatch.encrypted_cookie_cipher,
+          "action_dispatch.signed_cookie_digest" => config.action_dispatch.signed_cookie_digest,
           "action_dispatch.cookies_serializer" => config.action_dispatch.cookies_serializer,
-          "action_dispatch.cookies_digest" => config.action_dispatch.cookies_digest
+          "action_dispatch.cookies_digest" => config.action_dispatch.cookies_digest,
+          "action_dispatch.cookies_rotations" => config.action_dispatch.cookies_rotations,
+          "action_dispatch.content_security_policy" => config.content_security_policy,
+          "action_dispatch.content_security_policy_report_only" => config.content_security_policy_report_only
         )
       end
     end
 
-    # If you try to define a set of rake tasks on the instance, these will get
-    # passed up to the rake tasks defined on the application's class.
+    # If you try to define a set of Rake tasks on the instance, these will get
+    # passed up to the Rake tasks defined on the application's class.
     def rake_tasks(&block)
       self.class.rake_tasks(&block)
     end
@@ -274,7 +282,7 @@ module Rails
     # Sends the initializers to the +initializer+ method defined in the
     # Rails::Initializable module. Each Rails::Application class has its own
     # set of initializers, as defined by the Initializable module.
-    def initializer(name, opts={}, &block)
+    def initializer(name, opts = {}, &block)
       self.class.initializer(name, opts, &block)
     end
 
@@ -317,7 +325,7 @@ module Rails
     # Rails application, you will need to add lib to $LOAD_PATH on your own in case
     # you need to load files in lib/ during the application configuration as well.
     def self.add_lib_to_load_path!(root) #:nodoc:
-      path = File.join root, 'lib'
+      path = File.join root, "lib"
       if File.exist?(path) && !$LOAD_PATH.include?(path)
         $LOAD_PATH.unshift(path)
       end
@@ -347,7 +355,7 @@ module Rails
 
     # Initialize the application passing the given group. By default, the
     # group is :default
-    def initialize!(group=:default) #:nodoc:
+    def initialize!(group = :default) #:nodoc:
       raise "Application has been already initialized." if @initialized
       run_initializers(group, self)
       @initialized = true
@@ -385,24 +393,21 @@ module Rails
     def secrets
       @secrets ||= begin
         secrets = ActiveSupport::OrderedOptions.new
-        yaml    = config.paths["config/secrets"].first
-
-        if File.exist?(yaml)
-          require "erb"
-
-          all_secrets    = YAML.load(ERB.new(IO.read(yaml)).result) || {}
-          shared_secrets = all_secrets['shared']
-          env_secrets    = all_secrets[Rails.env]
-
-          secrets.merge!(shared_secrets.symbolize_keys) if shared_secrets
-          secrets.merge!(env_secrets.symbolize_keys) if env_secrets
-        end
+        files = config.paths["config/secrets"].existent
+        files = files.reject { |path| path.end_with?(".enc") } unless config.read_encrypted_secrets
+        secrets.merge! Rails::Secrets.parse(files, env: Rails.env)
 
         # Fallback to config.secret_key_base if secrets.secret_key_base isn't set
         secrets.secret_key_base ||= config.secret_key_base
         # Fallback to config.secret_token if secrets.secret_token isn't set
         secrets.secret_token ||= config.secret_token
 
+        if secrets.secret_token.present?
+          ActiveSupport::Deprecation.warn(
+            "`secrets.secret_token` is deprecated in favor of `secret_key_base` and will be removed in Rails 6.0."
+          )
+        end
+
         secrets
       end
     end
@@ -411,6 +416,67 @@ module Rails
       @secrets = secrets
     end
 
+    # The secret_key_base is used as the input secret to the application's key generator, which in turn
+    # is used to create all MessageVerifiers/MessageEncryptors, including the ones that sign and encrypt cookies.
+    #
+    # In test and development, this is simply derived as a MD5 hash of the application's name.
+    #
+    # In all other environments, we look for it first in ENV["SECRET_KEY_BASE"],
+    # then credentials.secret_key_base, and finally secrets.secret_key_base. For most applications,
+    # the correct place to store it is in the encrypted credentials file.
+    def secret_key_base
+      if Rails.env.test? || Rails.env.development?
+        Digest::MD5.hexdigest self.class.name
+      else
+        validate_secret_key_base(
+          ENV["SECRET_KEY_BASE"] || credentials.secret_key_base || secrets.secret_key_base
+        )
+      end
+    end
+
+    # Decrypts the credentials hash as kept in +config/credentials.yml.enc+. This file is encrypted with
+    # the Rails master key, which is either taken from <tt>ENV["RAILS_MASTER_KEY"]</tt> or from loading
+    # +config/master.key+.
+    def credentials
+      @credentials ||= encrypted("config/credentials.yml.enc")
+    end
+
+    # Shorthand to decrypt any encrypted configurations or files.
+    #
+    # For any file added with <tt>bin/rails encrypted:edit</tt> call +read+ to decrypt
+    # the file with the master key.
+    # The master key is either stored in +config/master.key+ or <tt>ENV["RAILS_MASTER_KEY"]</tt>.
+    #
+    #   Rails.application.encrypted("config/mystery_man.txt.enc").read
+    #   # => "We've met before, haven't we?"
+    #
+    # It's also possible to interpret encrypted YAML files with +config+.
+    #
+    #   Rails.application.encrypted("config/credentials.yml.enc").config
+    #   # => { next_guys_line: "I don't think so. Where was it you think we met?" }
+    #
+    # Any top-level configs are also accessible directly on the return value:
+    #
+    #   Rails.application.encrypted("config/credentials.yml.enc").next_guys_line
+    #   # => "I don't think so. Where was it you think we met?"
+    #
+    # The files or configs can also be encrypted with a custom key. To decrypt with
+    # a key in the +ENV+, use:
+    #
+    #   Rails.application.encrypted("config/special_tokens.yml.enc", env_key: "SPECIAL_TOKENS")
+    #
+    # Or to decrypt with a file, that should be version control ignored, relative to +Rails.root+:
+    #
+    #   Rails.application.encrypted("config/special_tokens.yml.enc", key_path: "config/special_tokens.key")
+    def encrypted(path, key_path: "config/master.key", env_key: "RAILS_MASTER_KEY")
+      ActiveSupport::EncryptedConfiguration.new(
+        config_path: Rails.root.join(path),
+        key_path: Rails.root.join(key_path),
+        env_key: env_key,
+        raise_if_missing_key: config.require_master_key
+      )
+    end
+
     def to_app #:nodoc:
       self
     end
@@ -509,28 +575,27 @@ module Rails
       default_stack.build_stack
     end
 
-    def validate_secret_key_config! #:nodoc:
-      if secrets.secret_key_base.blank?
-        ActiveSupport::Deprecation.warn "You didn't set `secret_key_base`. " +
-          "Read the upgrade documentation to learn more about this new config option."
-
-        if secrets.secret_token.blank?
-          raise "Missing `secret_key_base` for '#{Rails.env}' environment, set this value in `config/secrets.yml`"
-        end
+    def validate_secret_key_base(secret_key_base)
+      if secret_key_base.is_a?(String) && secret_key_base.present?
+        secret_key_base
+      elsif secret_key_base
+        raise ArgumentError, "`secret_key_base` for #{Rails.env} environment must be a type of String`"
+      elsif secrets.secret_token.blank?
+        raise ArgumentError, "Missing `secret_key_base` for '#{Rails.env}' environment, set this string with `rails credentials:edit`"
       end
     end
 
     private
 
-    def build_request(env)
-      req = super
-      env["ORIGINAL_FULLPATH"] = req.fullpath
-      env["ORIGINAL_SCRIPT_NAME"] = req.script_name
-      req
-    end
+      def build_request(env)
+        req = super
+        env["ORIGINAL_FULLPATH"] = req.fullpath
+        env["ORIGINAL_SCRIPT_NAME"] = req.script_name
+        req
+      end
 
-    def build_middleware
-      config.app_middleware + super
-    end
+      def build_middleware
+        config.app_middleware + super
+      end
   end
 end
diff --git a/railties/lib/rails/application/bootstrap.rb b/railties/lib/rails/application/bootstrap.rb
index f615f22b26..e3c0759f95 100644
--- a/railties/lib/rails/application/bootstrap.rb
+++ b/railties/lib/rails/application/bootstrap.rb
@@ -1,7 +1,10 @@
-require 'fileutils'
-require 'active_support/notifications'
-require 'active_support/dependencies'
-require 'active_support/descendants_tracker'
+# frozen_string_literal: true
+
+require "fileutils"
+require "active_support/notifications"
+require "active_support/dependencies"
+require "active_support/descendants_tracker"
+require "rails/secrets"
 
 module Rails
   class Application
@@ -36,7 +39,7 @@ INFO
             FileUtils.mkdir_p File.dirname path
           end
 
-          f = File.open path, 'a'
+          f = File.open path, "a"
           f.binmode
           f.sync = config.autoflush_log # if true make sure every write flushes
 
@@ -48,8 +51,8 @@ INFO
           logger = ActiveSupport::TaggedLogging.new(ActiveSupport::Logger.new(STDERR))
           logger.level = ActiveSupport::Logger::WARN
           logger.warn(
-            "Rails Error: Unable to access log file. Please ensure that #{path} exists and is writable " +
-            "(ie, make it writable for user and group: chmod 0664 #{path}). " +
+            "Rails Error: Unable to access log file. Please ensure that #{path} exists and is writable " \
+            "(ie, make it writable for user and group: chmod 0664 #{path}). " \
             "The log level has been raised to WARN and the output directed to STDERR until the problem is fixed."
           )
           logger
@@ -77,6 +80,10 @@ INFO
       initializer :bootstrap_hook, group: :all do |app|
         ActiveSupport.run_load_hooks(:before_initialize, app)
       end
+
+      initializer :set_secrets_root, group: :all do
+        Rails::Secrets.root = root
+      end
     end
   end
 end
diff --git a/railties/lib/rails/application/configuration.rb b/railties/lib/rails/application/configuration.rb
index f415a20833..5d8d6740c8 100644
--- a/railties/lib/rails/application/configuration.rb
+++ b/railties/lib/rails/application/configuration.rb
@@ -1,10 +1,9 @@
-require 'active_support/core_ext/kernel/reporting'
-require 'active_support/file_update_checker'
-require 'rails/engine/configuration'
-require 'rails/source_annotation_extractor'
+# frozen_string_literal: true
 
-require 'active_support/deprecation'
-require 'active_support/core_ext/string/strip' # for strip_heredoc
+require "active_support/core_ext/kernel/reporting"
+require "active_support/file_update_checker"
+require "rails/engine/configuration"
+require "rails/source_annotation_extractor"
 
 module Rails
   class Application
@@ -16,73 +15,105 @@ module Rails
                     :railties_order, :relative_url_root, :secret_key_base, :secret_token,
                     :ssl_options, :public_file_server,
                     :session_options, :time_zone, :reload_classes_only_on_change,
-                    :beginning_of_week, :filter_redirect, :x
+                    :beginning_of_week, :filter_redirect, :x, :enable_dependency_loading,
+                    :read_encrypted_secrets, :log_level, :content_security_policy_report_only,
+                    :require_master_key
 
-      attr_writer :log_level
-      attr_reader :encoding, :api_only, :static_cache_control
+      attr_reader :encoding, :api_only
 
       def initialize(*)
         super
-        self.encoding = "utf-8"
-        @allow_concurrency               = nil
-        @consider_all_requests_local     = false
-        @filter_parameters               = []
-        @filter_redirect                 = []
-        @helpers_paths                   = []
-        @public_file_server              = ActiveSupport::OrderedOptions.new
-        @public_file_server.enabled      = true
-        @public_file_server.index_name   = "index"
-        @force_ssl                       = false
-        @ssl_options                     = {}
-        @session_store                   = :cookie_store
-        @session_options                 = {}
-        @time_zone                       = "UTC"
-        @beginning_of_week               = :monday
-        @log_level                       = nil
-        @generators                      = app_generators
-        @cache_store                     = [ :file_store, "#{root}/tmp/cache/" ]
-        @railties_order                  = [:all]
-        @relative_url_root               = ENV["RAILS_RELATIVE_URL_ROOT"]
-        @reload_classes_only_on_change   = true
-        @file_watcher                    = ActiveSupport::FileUpdateChecker
-        @exceptions_app                  = nil
-        @autoflush_log                   = true
-        @log_formatter                   = ActiveSupport::Logger::SimpleFormatter.new
-        @eager_load                      = nil
-        @secret_token                    = nil
-        @secret_key_base                 = nil
-        @api_only                        = false
-        @debug_exception_response_format = nil
-        @x                               = Custom.new
+        self.encoding                        = Encoding::UTF_8
+        @allow_concurrency                   = nil
+        @consider_all_requests_local         = false
+        @filter_parameters                   = []
+        @filter_redirect                     = []
+        @helpers_paths                       = []
+        @public_file_server                  = ActiveSupport::OrderedOptions.new
+        @public_file_server.enabled          = true
+        @public_file_server.index_name       = "index"
+        @force_ssl                           = false
+        @ssl_options                         = {}
+        @session_store                       = nil
+        @time_zone                           = "UTC"
+        @beginning_of_week                   = :monday
+        @log_level                           = :debug
+        @generators                          = app_generators
+        @cache_store                         = [ :file_store, "#{root}/tmp/cache/" ]
+        @railties_order                      = [:all]
+        @relative_url_root                   = ENV["RAILS_RELATIVE_URL_ROOT"]
+        @reload_classes_only_on_change       = true
+        @file_watcher                        = ActiveSupport::FileUpdateChecker
+        @exceptions_app                      = nil
+        @autoflush_log                       = true
+        @log_formatter                       = ActiveSupport::Logger::SimpleFormatter.new
+        @eager_load                          = nil
+        @secret_token                        = nil
+        @secret_key_base                     = nil
+        @api_only                            = false
+        @debug_exception_response_format     = nil
+        @x                                   = Custom.new
+        @enable_dependency_loading           = false
+        @read_encrypted_secrets              = false
+        @content_security_policy             = nil
+        @content_security_policy_report_only = false
+        @require_master_key                  = false
       end
 
-      def static_cache_control=(value)
-        ActiveSupport::Deprecation.warn <<-eow.strip_heredoc
-          `config.static_cache_control` is deprecated and will be removed in Rails 5.1.
-          Please use
-          `config.public_file_server.headers = { 'Cache-Control' => '#{value}' }`
-          instead.
-        eow
+      def load_defaults(target_version)
+        case target_version.to_s
+        when "5.0"
+          if respond_to?(:action_controller)
+            action_controller.per_form_csrf_tokens = true
+            action_controller.forgery_protection_origin_check = true
+          end
 
-        @static_cache_control = value
-      end
+          ActiveSupport.to_time_preserves_timezone = true
 
-      def serve_static_files
-        ActiveSupport::Deprecation.warn <<-eow.strip_heredoc
-          `config.serve_static_files` is deprecated and will be removed in Rails 5.1.
-          Please use `config.public_file_server.enabled` instead.
-        eow
+          if respond_to?(:active_record)
+            active_record.belongs_to_required_by_default = true
+          end
 
-        @public_file_server.enabled
-      end
+          self.ssl_options = { hsts: { subdomains: true } }
+        when "5.1"
+          load_defaults "5.0"
 
-      def serve_static_files=(value)
-        ActiveSupport::Deprecation.warn <<-eow.strip_heredoc
-          `config.serve_static_files` is deprecated and will be removed in Rails 5.1.
-          Please use `config.public_file_server.enabled = #{value}` instead.
-        eow
+          if respond_to?(:assets)
+            assets.unknown_asset_fallback = false
+          end
 
-        @public_file_server.enabled = value
+          if respond_to?(:action_view)
+            action_view.form_with_generates_remote_forms = true
+          end
+        when "5.2"
+          load_defaults "5.1"
+
+          if respond_to?(:active_record)
+            active_record.cache_versioning = true
+            # Remove the temporary load hook from SQLite3Adapter when this is removed
+            ActiveSupport.on_load(:active_record_sqlite3adapter) do
+              ActiveRecord::ConnectionAdapters::SQLite3Adapter.represent_boolean_as_integer = true
+            end
+          end
+
+          if respond_to?(:action_dispatch)
+            action_dispatch.use_authenticated_cookie_encryption = true
+          end
+
+          if respond_to?(:active_support)
+            active_support.use_authenticated_message_encryption = true
+          end
+
+          if respond_to?(:action_controller)
+            action_controller.default_protect_from_forgery = true
+          end
+
+          if respond_to?(:action_view)
+            action_view.form_with_generates_ids = true
+          end
+        else
+          raise "Unknown version #{target_version.to_s.inspect}"
+        end
       end
 
       def encoding=(value)
@@ -112,7 +143,7 @@ module Rails
         @paths ||= begin
           paths = super
           paths.add "config/database",    with: "config/database.yml"
-          paths.add "config/secrets",     with: "config/secrets.yml"
+          paths.add "config/secrets",     with: "config", glob: "secrets.yml{,.enc}"
           paths.add "config/environment", with: "config/environment.rb"
           paths.add "lib/templates"
           paths.add "log",                with: "log/#{Rails.env}.log"
@@ -125,7 +156,7 @@ module Rails
       end
 
       # Loads and returns the entire raw configuration of database from
-      # values stored in `config/database.yml`.
+      # values stored in <tt>config/database.yml</tt>.
       def database_configuration
         path = paths["config/database"].existent.first
         yaml = Pathname.new(path) if path
@@ -133,8 +164,15 @@ module Rails
         config = if yaml && yaml.exist?
           require "yaml"
           require "erb"
-          YAML.load(ERB.new(yaml.read).result) || {}
-        elsif ENV['DATABASE_URL']
+          loaded_yaml = YAML.load(ERB.new(yaml.read).result) || {}
+          shared = loaded_yaml.delete("shared")
+          if shared
+            loaded_yaml.each do |_k, values|
+              values.reverse_merge!(shared)
+            end
+          end
+          Hash.new(shared).merge(loaded_yaml)
+        elsif ENV["DATABASE_URL"]
           # Value from ENV['DATABASE_URL'] is set to default database connection
           # by Active Record.
           {}
@@ -151,46 +189,54 @@ module Rails
         raise e, "Cannot load `Rails.application.database_configuration`:\n#{e.message}", e.backtrace
       end
 
-      def log_level
-        @log_level ||= (Rails.env.production? ? :info : :debug)
-      end
-
       def colorize_logging
         ActiveSupport::LogSubscriber.colorize_logging
       end
 
       def colorize_logging=(val)
         ActiveSupport::LogSubscriber.colorize_logging = val
-        self.generators.colorize_logging = val
+        generators.colorize_logging = val
       end
 
-      def session_store(*args)
-        if args.empty?
-          case @session_store
-          when :disabled
-            nil
-          when :active_record_store
+      def session_store(new_session_store = nil, **options)
+        if new_session_store
+          if new_session_store == :active_record_store
             begin
               ActionDispatch::Session::ActiveRecordStore
             rescue NameError
               raise "`ActiveRecord::SessionStore` is extracted out of Rails into a gem. " \
                 "Please add `activerecord-session_store` to your Gemfile to use it."
             end
+          end
+
+          @session_store = new_session_store
+          @session_options = options || {}
+        else
+          case @session_store
+          when :disabled
+            nil
+          when :active_record_store
+            ActionDispatch::Session::ActiveRecordStore
           when Symbol
             ActionDispatch::Session.const_get(@session_store.to_s.camelize)
           else
             @session_store
           end
-        else
-          @session_store = args.shift
-          @session_options = args.shift || {}
         end
       end
 
+      def session_store? #:nodoc:
+        @session_store
+      end
+
       def annotations
         SourceAnnotationExtractor::Annotation
       end
 
+      def content_security_policy(&block)
+        @content_security_policy ||= ActionDispatch::ContentSecurityPolicy.new(&block)
+      end
+
       class Custom #:nodoc:
         def initialize
           @configurations = Hash.new
@@ -205,6 +251,10 @@ module Rails
             }
           end
         end
+
+        def respond_to_missing?(symbol, *)
+          true
+        end
       end
     end
   end
diff --git a/railties/lib/rails/application/default_middleware_stack.rb b/railties/lib/rails/application/default_middleware_stack.rb
index 381e548730..0e79ba7da0 100644
--- a/railties/lib/rails/application/default_middleware_stack.rb
+++ b/railties/lib/rails/application/default_middleware_stack.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module Rails
   class Application
     class DefaultMiddlewareStack
@@ -10,7 +12,7 @@ module Rails
       end
 
       def build_stack
-        ActionDispatch::MiddlewareStack.new.tap do |middleware|
+        ActionDispatch::MiddlewareStack.new do |middleware|
           if config.force_ssl
             middleware.use ::ActionDispatch::SSL, config.ssl_options
           end
@@ -19,7 +21,6 @@ module Rails
 
           if config.public_file_server.enabled
             headers = config.public_file_server.headers || {}
-            headers['Cache-Control'.freeze] = config.static_cache_control if config.static_cache_control
 
             middleware.use ::ActionDispatch::Static, paths["public"].first, index: config.public_file_server.index_name, headers: headers
           end
@@ -41,12 +42,11 @@ module Rails
           middleware.use ::Rack::Runtime
           middleware.use ::Rack::MethodOverride unless config.api_only
           middleware.use ::ActionDispatch::RequestId
+          middleware.use ::ActionDispatch::RemoteIp, config.action_dispatch.ip_spoofing_check, config.action_dispatch.trusted_proxies
 
-          # Must come after Rack::MethodOverride to properly log overridden methods
           middleware.use ::Rails::Rack::Logger, config.log_tags
           middleware.use ::ActionDispatch::ShowExceptions, show_exceptions_app
           middleware.use ::ActionDispatch::DebugExceptions, app, config.debug_exception_response_format
-          middleware.use ::ActionDispatch::RemoteIp, config.action_dispatch.ip_spoofing_check, config.action_dispatch.trusted_proxies
 
           unless config.cache_classes
             middleware.use ::ActionDispatch::Reloader, app.reloader
@@ -63,6 +63,10 @@ module Rails
             middleware.use ::ActionDispatch::Flash
           end
 
+          unless config.api_only
+            middleware.use ::ActionDispatch::ContentSecurityPolicy::Middleware
+          end
+
           middleware.use ::Rack::Head
           middleware.use ::Rack::ConditionalGet
           middleware.use ::Rack::ETag, "no-cache"
@@ -76,9 +80,9 @@ module Rails
           return unless rack_cache
 
           begin
-            require 'rack/cache'
+            require "rack/cache"
           rescue LoadError => error
-            error.message << ' Be sure to add rack-cache to your Gemfile'
+            error.message << " Be sure to add rack-cache to your Gemfile"
             raise
           end
 
diff --git a/railties/lib/rails/application/finisher.rb b/railties/lib/rails/application/finisher.rb
index 97dde9a3e9..c4b188aeee 100644
--- a/railties/lib/rails/application/finisher.rb
+++ b/railties/lib/rails/application/finisher.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module Rails
   class Application
     module Finisher
@@ -22,17 +24,25 @@ module Rails
       initializer :add_builtin_route do |app|
         if Rails.env.development?
           app.routes.prepend do
-            get '/rails/info/properties' => "rails/info#properties", internal: true
-            get '/rails/info/routes'     => "rails/info#routes", internal: true
-            get '/rails/info'            => "rails/info#index", internal: true
+            get "/rails/info/properties" => "rails/info#properties", internal: true
+            get "/rails/info/routes"     => "rails/info#routes", internal: true
+            get "/rails/info"            => "rails/info#index", internal: true
           end
 
           app.routes.append do
-            get '/'                      => "rails/welcome#index", internal: true
+            get "/"                      => "rails/welcome#index", internal: true
           end
         end
       end
 
+      # Setup default session store if not already set in config/application.rb
+      initializer :setup_default_session_store, before: :build_middleware_stack do |app|
+        unless app.config.session_store?
+          app_name = app.class.name ? app.railtie_name.chomp("_application") : ""
+          app.config.session_store :cookie_store, key: "_#{app_name}_session"
+        end
+      end
+
       initializer :build_middleware_stack do
         build_middleware_stack
       end
@@ -48,7 +58,7 @@ module Rails
       end
 
       # This needs to happen before eager load so it happens
-      # in exactly the same point regardless of config.cache_classes
+      # in exactly the same point regardless of config.eager_load
       initializer :run_prepare_callbacks do |app|
         app.reloader.prepare!
       end
@@ -116,8 +126,9 @@ module Rails
       # the hook are taken into account.
       initializer :set_routes_reloader_hook do |app|
         reloader = routes_reloader
+        reloader.eager_load = app.config.eager_load
         reloader.execute_if_updated
-        self.reloaders << reloader
+        reloaders << reloader
         app.reloader.to_run do
           # We configure #execute rather than #execute_if_updated because if
           # autoloaded constants are cleared we need to reload routes also in
@@ -153,7 +164,7 @@ module Rails
 
         if config.reload_classes_only_on_change
           reloader = config.file_watcher.new(*watchable_args, &callback)
-          self.reloaders << reloader
+          reloaders << reloader
 
           # Prepend this callback to have autoloaded constants cleared before
           # any other possible reloading, in case they need to autoload fresh
@@ -176,7 +187,7 @@ module Rails
 
       # Disable dependency loading during request cycle
       initializer :disable_dependency_loading do
-        if config.eager_load && config.cache_classes
+        if config.eager_load && config.cache_classes && !config.enable_dependency_loading
           ActiveSupport::Dependencies.unhook!
         end
       end
diff --git a/railties/lib/rails/application/routes_reloader.rb b/railties/lib/rails/application/routes_reloader.rb
index cf0a4e128f..2ef09b4162 100644
--- a/railties/lib/rails/application/routes_reloader.rb
+++ b/railties/lib/rails/application/routes_reloader.rb
@@ -1,14 +1,18 @@
+# frozen_string_literal: true
+
 require "active_support/core_ext/module/delegation"
 
 module Rails
   class Application
     class RoutesReloader
       attr_reader :route_sets, :paths
-      delegate :execute_if_updated, :execute, :updated?, to: :updater
+      attr_accessor :eager_load
+      delegate :updated?, to: :updater
 
       def initialize
         @paths      = []
         @route_sets = []
+        @eager_load = false
       end
 
       def reload!
@@ -19,6 +23,19 @@ module Rails
         revert
       end
 
+      def execute
+        ret = updater.execute
+        route_sets.each(&:eager_load!) if eager_load
+        ret
+      end
+
+      def execute_if_updated
+        if updated = updater.execute_if_updated
+          route_sets.each(&:eager_load!) if eager_load
+        end
+        updated
+      end
+
     private
 
       def updater
diff --git a/railties/lib/rails/application_controller.rb b/railties/lib/rails/application_controller.rb
index 618a09a5b3..fa8793d81a 100644
--- a/railties/lib/rails/application_controller.rb
+++ b/railties/lib/rails/application_controller.rb
@@ -1,16 +1,18 @@
+# frozen_string_literal: true
+
 class Rails::ApplicationController < ActionController::Base # :nodoc:
-  self.view_paths = File.expand_path('../templates', __FILE__)
-  layout 'application'
+  self.view_paths = File.expand_path("templates", __dir__)
+  layout "application"
 
-  protected
+  private
 
-  def require_local!
-    unless local_request?
-      render html: '<p>For security purposes, this information is only available to local requests.</p>'.html_safe, status: :forbidden
+    def require_local!
+      unless local_request?
+        render html: "<p>For security purposes, this information is only available to local requests.</p>".html_safe, status: :forbidden
+      end
     end
-  end
 
-  def local_request?
-    Rails.application.config.consider_all_requests_local || request.local?
-  end
+    def local_request?
+      Rails.application.config.consider_all_requests_local || request.local?
+    end
 end
diff --git a/railties/lib/rails/backtrace_cleaner.rb b/railties/lib/rails/backtrace_cleaner.rb
index 5276eb33c9..ae8db0f8ef 100644
--- a/railties/lib/rails/backtrace_cleaner.rb
+++ b/railties/lib/rails/backtrace_cleaner.rb
@@ -1,12 +1,14 @@
-require 'active_support/backtrace_cleaner'
+# frozen_string_literal: true
+
+require "active_support/backtrace_cleaner"
 
 module Rails
   class BacktraceCleaner < ActiveSupport::BacktraceCleaner
-    APP_DIRS_PATTERN = /^\/?(app|config|lib|test)/
+    APP_DIRS_PATTERN = /^\/?(app|config|lib|test|\(\w*\))/
     RENDER_TEMPLATE_PATTERN = /:in `_render_template_\w*'/
-    EMPTY_STRING = ''.freeze
-    SLASH        = '/'.freeze
-    DOT_SLASH    = './'.freeze
+    EMPTY_STRING = "".freeze
+    SLASH        = "/".freeze
+    DOT_SLASH    = "./".freeze
 
     def initialize
       super
@@ -16,7 +18,7 @@ module Rails
       add_filter { |line| line.sub(DOT_SLASH, SLASH) } # for tests
 
       add_gem_filters
-      add_silencer { |line| line !~ APP_DIRS_PATTERN }
+      add_silencer { |line| !APP_DIRS_PATTERN.match?(line) }
     end
 
     private
diff --git a/railties/lib/rails/cli.rb b/railties/lib/rails/cli.rb
index a8794bc0de..e56e604fdc 100644
--- a/railties/lib/rails/cli.rb
+++ b/railties/lib/rails/cli.rb
@@ -1,15 +1,19 @@
-require 'rails/app_loader'
+# frozen_string_literal: true
+
+require "rails/app_loader"
 
 # If we are inside a Rails application this method performs an exec and thus
 # the rest of this script is not run.
 Rails::AppLoader.exec_app
 
-require 'rails/ruby_version_check'
+require "rails/ruby_version_check"
 Signal.trap("INT") { puts; exit(1) }
 
-if ARGV.first == 'plugin'
+require "rails/command"
+
+if ARGV.first == "plugin"
   ARGV.shift
-  require 'rails/commands/plugin'
+  Rails::Command.invoke :plugin, ARGV
 else
-  require 'rails/commands/application'
+  Rails::Command.invoke :application, ARGV
 end
diff --git a/railties/lib/rails/code_statistics.rb b/railties/lib/rails/code_statistics.rb
index 7a8f42fe94..9c447c366f 100644
--- a/railties/lib/rails/code_statistics.rb
+++ b/railties/lib/rails/code_statistics.rb
@@ -1,16 +1,18 @@
-require 'rails/code_statistics_calculator'
-require 'active_support/core_ext/enumerable'
+# frozen_string_literal: true
 
-class CodeStatistics #:nodoc:
+require "rails/code_statistics_calculator"
+require "active_support/core_ext/enumerable"
 
-  TEST_TYPES = ['Controller tests',
-                'Helper tests',
-                'Model tests',
-                'Mailer tests',
-                'Job tests',
-                'Integration tests']
+class CodeStatistics #:nodoc:
+  TEST_TYPES = ["Controller tests",
+                "Helper tests",
+                "Model tests",
+                "Mailer tests",
+                "Job tests",
+                "Integration tests",
+                "System tests"]
 
-  HEADERS = {lines: ' Lines', code_lines: '   LOC', classes: 'Classes', methods: 'Methods'}
+  HEADERS = { lines: " Lines", code_lines: "   LOC", classes: "Classes", methods: "Methods" }
 
   def initialize(*pairs)
     @pairs      = pairs
@@ -33,7 +35,7 @@ class CodeStatistics #:nodoc:
 
   private
     def calculate_statistics
-      Hash[@pairs.map{|pair| [pair.first, calculate_directory_statistics(pair.last)]}]
+      Hash[@pairs.map { |pair| [pair.first, calculate_directory_statistics(pair.last)] }]
     end
 
     def calculate_directory_statistics(directory, pattern = /^(?!\.).*?\.(rb|js|coffee|rake)$/)
@@ -71,25 +73,25 @@ class CodeStatistics #:nodoc:
     end
 
     def width_for(label)
-      [@statistics.values.sum {|s| s.send(label) }.to_s.size, HEADERS[label].length].max
+      [@statistics.values.sum { |s| s.send(label) }.to_s.size, HEADERS[label].length].max
     end
 
     def print_header
       print_splitter
-      print '| Name                '
+      print "| Name                "
       HEADERS.each do |k, v|
         print " | #{v.rjust(width_for(k))}"
       end
-      puts ' | M/C | LOC/M |'
+      puts " | M/C | LOC/M |"
       print_splitter
     end
 
     def print_splitter
-      print '+----------------------'
+      print "+----------------------"
       HEADERS.each_key do |k|
         print "+#{'-' * (width_for(k) + 2)}"
       end
-      puts '+-----+-------+'
+      puts "+-----+-------+"
     end
 
     def print_line(name, statistics)
@@ -107,7 +109,7 @@ class CodeStatistics #:nodoc:
       code  = calculate_code
       tests = calculate_tests
 
-      puts "  Code LOC: #{code}     Test LOC: #{tests}     Code to Test Ratio: 1:#{sprintf("%.1f", tests.to_f/code)}"
+      puts "  Code LOC: #{code}     Test LOC: #{tests}     Code to Test Ratio: 1:#{sprintf("%.1f", tests.to_f / code)}"
       puts ""
     end
 end
diff --git a/railties/lib/rails/code_statistics_calculator.rb b/railties/lib/rails/code_statistics_calculator.rb
index fad13e8517..85f86bdbd0 100644
--- a/railties/lib/rails/code_statistics_calculator.rb
+++ b/railties/lib/rails/code_statistics_calculator.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class CodeStatisticsCalculator #:nodoc:
   attr_reader :lines, :code_lines, :classes, :methods
 
@@ -43,7 +45,7 @@ class CodeStatisticsCalculator #:nodoc:
 
   def add_by_file_path(file_path)
     File.open(file_path) do |f|
-      self.add_by_io(f, file_type(file_path))
+      add_by_io(f, file_type(file_path))
     end
   end
 
@@ -77,10 +79,10 @@ class CodeStatisticsCalculator #:nodoc:
 
   private
     def file_type(file_path)
-      if file_path.end_with? '_test.rb'
+      if file_path.end_with? "_test.rb"
         :minitest
       else
-        File.extname(file_path).sub(/\A\./, '').downcase.to_sym
+        File.extname(file_path).sub(/\A\./, "").downcase.to_sym
       end
     end
 end
diff --git a/railties/lib/rails/command.rb b/railties/lib/rails/command.rb
new file mode 100644
index 0000000000..812e846837
--- /dev/null
+++ b/railties/lib/rails/command.rb
@@ -0,0 +1,113 @@
+# frozen_string_literal: true
+
+require "active_support"
+require "active_support/dependencies/autoload"
+require "active_support/core_ext/enumerable"
+require "active_support/core_ext/object/blank"
+require "active_support/core_ext/hash/transform_values"
+
+require "thor"
+
+module Rails
+  module Command
+    extend ActiveSupport::Autoload
+
+    autoload :Behavior
+    autoload :Base
+
+    include Behavior
+
+    HELP_MAPPINGS = %w(-h -? --help)
+
+    class << self
+      def hidden_commands # :nodoc:
+        @hidden_commands ||= []
+      end
+
+      def environment # :nodoc:
+        ENV["RAILS_ENV"].presence || ENV["RACK_ENV"].presence || "development"
+      end
+
+      # Receives a namespace, arguments and the behavior to invoke the command.
+      def invoke(full_namespace, args = [], **config)
+        namespace = full_namespace = full_namespace.to_s
+
+        if char = namespace =~ /:(\w+)$/
+          command_name, namespace = $1, namespace.slice(0, char)
+        else
+          command_name = namespace
+        end
+
+        command_name, namespace = "help", "help" if command_name.blank? || HELP_MAPPINGS.include?(command_name)
+        command_name, namespace = "version", "version" if %w( -v --version ).include?(command_name)
+
+        command = find_by_namespace(namespace, command_name)
+        if command && command.all_commands[command_name]
+          command.perform(command_name, args, config)
+        else
+          find_by_namespace("rake").perform(full_namespace, args, config)
+        end
+      end
+
+      # Rails finds namespaces similar to Thor, it only adds one rule:
+      #
+      # Command names must end with "_command.rb". This is required because Rails
+      # looks in load paths and loads the command just before it's going to be used.
+      #
+      #   find_by_namespace :webrat, :rails, :integration
+      #
+      # Will search for the following commands:
+      #
+      #   "rails:webrat", "webrat:integration", "webrat"
+      #
+      # Notice that "rails:commands:webrat" could be loaded as well, what
+      # Rails looks for is the first and last parts of the namespace.
+      def find_by_namespace(namespace, command_name = nil) # :nodoc:
+        lookups = [ namespace ]
+        lookups << "#{namespace}:#{command_name}" if command_name
+        lookups.concat lookups.map { |lookup| "rails:#{lookup}" }
+
+        lookup(lookups)
+
+        namespaces = subclasses.index_by(&:namespace)
+        namespaces[(lookups & namespaces.keys).first]
+      end
+
+      # Returns the root of the Rails engine or app running the command.
+      def root
+        if defined?(ENGINE_ROOT)
+          Pathname.new(ENGINE_ROOT)
+        elsif defined?(APP_PATH)
+          Pathname.new(File.expand_path("../..", APP_PATH))
+        end
+      end
+
+      def print_commands # :nodoc:
+        sorted_groups.each { |b, n| print_list(b, n) }
+      end
+
+      def sorted_groups # :nodoc:
+        lookup!
+
+        groups = (subclasses - hidden_commands).group_by { |c| c.namespace.split(":").first }
+        groups.transform_values! { |commands| commands.flat_map(&:printing_commands).sort }
+
+        rails = groups.delete("rails")
+        [[ "rails", rails ]] + groups.sort.to_a
+      end
+
+      private
+        def command_type # :doc:
+          @command_type ||= "command"
+        end
+
+        def lookup_paths # :doc:
+          @lookup_paths ||= %w( rails/commands commands )
+        end
+
+        def file_lookup_paths # :doc:
+          @file_lookup_paths ||= [ "{#{lookup_paths.join(',')}}", "**", "*_command.rb" ]
+        end
+    end
+  end
+end
diff --git a/railties/lib/rails/command/actions.rb b/railties/lib/rails/command/actions.rb
new file mode 100644
index 0000000000..cbb743346b
--- /dev/null
+++ b/railties/lib/rails/command/actions.rb
@@ -0,0 +1,44 @@
+# frozen_string_literal: true
+
+module Rails
+  module Command
+    module Actions
+      # Change to the application's path if there is no <tt>config.ru</tt> file in current directory.
+      # This allows us to run <tt>rails server</tt> from other directories, but still get
+      # the main <tt>config.ru</tt> and properly set the <tt>tmp</tt> directory.
+      def set_application_directory!
+        Dir.chdir(File.expand_path("../..", APP_PATH)) unless File.exist?(File.expand_path("config.ru"))
+      end
+
+      def require_application_and_environment!
+        require ENGINE_PATH if defined?(ENGINE_PATH)
+
+        if defined?(APP_PATH)
+          require APP_PATH
+          Rails.application.require_environment!
+        end
+      end
+
+      if defined?(ENGINE_PATH)
+        def load_tasks
+          Rake.application.init("rails")
+          Rake.application.load_rakefile
+        end
+
+        def load_generators
+          engine = ::Rails::Engine.find(ENGINE_ROOT)
+          Rails::Generators.namespace = engine.railtie_namespace
+          engine.load_generators
+        end
+      else
+        def load_tasks
+          Rails.application.load_tasks
+        end
+
+        def load_generators
+          Rails.application.load_generators
+        end
+      end
+    end
+  end
+end
diff --git a/railties/lib/rails/command/base.rb b/railties/lib/rails/command/base.rb
new file mode 100644
index 0000000000..fa462ef7e9
--- /dev/null
+++ b/railties/lib/rails/command/base.rb
@@ -0,0 +1,157 @@
+# frozen_string_literal: true
+
+require "thor"
+require "erb"
+
+require "active_support/core_ext/string/filters"
+require "active_support/core_ext/string/inflections"
+
+require "rails/command/actions"
+
+module Rails
+  module Command
+    class Base < Thor
+      class Error < Thor::Error # :nodoc:
+      end
+
+      include Actions
+
+      class << self
+        # Returns true when the app is a Rails engine.
+        def engine?
+          defined?(ENGINE_ROOT)
+        end
+
+        # Tries to get the description from a USAGE file one folder above the command
+        # root.
+        def desc(usage = nil, description = nil, options = {})
+          if usage
+            super
+          else
+            @desc ||= ERB.new(File.read(usage_path)).result(binding) if usage_path
+          end
+        end
+
+        # Convenience method to get the namespace from the class name. It's the
+        # same as Thor default except that the Command at the end of the class
+        # is removed.
+        def namespace(name = nil)
+          if name
+            super
+          else
+            @namespace ||= super.chomp("_command").sub(/:command:/, ":")
+          end
+        end
+
+        # Convenience method to hide this command from the available ones when
+        # running rails command.
+        def hide_command!
+          Rails::Command.hidden_commands << self
+        end
+
+        def inherited(base) #:nodoc:
+          super
+
+          if base.name && base.name !~ /Base$/
+            Rails::Command.subclasses << base
+          end
+        end
+
+        def perform(command, args, config) # :nodoc:
+          if Rails::Command::HELP_MAPPINGS.include?(args.first)
+            command, args = "help", []
+          end
+
+          dispatch(command, args.dup, nil, config)
+        end
+
+        def printing_commands
+          namespaced_commands
+        end
+
+        def executable
+          "bin/rails #{command_name}"
+        end
+
+        # Use Rails' default banner.
+        def banner(*)
+          "#{executable} #{arguments.map(&:usage).join(' ')} [options]".squish
+        end
+
+        # Sets the base_name taking into account the current class namespace.
+        #
+        #   Rails::Command::TestCommand.base_name # => 'rails'
+        def base_name
+          @base_name ||= begin
+            if base = name.to_s.split("::").first
+              base.underscore
+            end
+          end
+        end
+
+        # Return command name without namespaces.
+        #
+        #   Rails::Command::TestCommand.command_name # => 'test'
+        def command_name
+          @command_name ||= begin
+            if command = name.to_s.split("::").last
+              command.chomp!("Command")
+              command.underscore
+            end
+          end
+        end
+
+        # Path to lookup a USAGE description in a file.
+        def usage_path
+          if default_command_root
+            path = File.join(default_command_root, "USAGE")
+            path if File.exist?(path)
+          end
+        end
+
+        # Default file root to place extra files a command might need, placed
+        # one folder above the command file.
+        #
+        # For a Rails::Command::TestCommand placed in <tt>rails/command/test_command.rb</tt>
+        # would return <tt>rails/test</tt>.
+        def default_command_root
+          path = File.expand_path(File.join("../commands", command_root_namespace), __dir__)
+          path if File.exist?(path)
+        end
+
+        private
+          # Allow the command method to be called perform.
+          def create_command(meth)
+            if meth == "perform"
+              alias_method command_name, meth
+            else
+              # Prevent exception about command without usage.
+              # Some commands define their documentation differently.
+              @usage ||= ""
+              @desc  ||= ""
+
+              super
+            end
+          end
+
+          def command_root_namespace
+            (namespace.split(":") - %w( rails )).first
+          end
+
+          def namespaced_commands
+            commands.keys.map do |key|
+              key == command_root_namespace ? key : "#{command_root_namespace}:#{key}"
+            end
+          end
+      end
+
+      def help
+        if command_name = self.class.command_name
+          self.class.command_help(shell, command_name)
+        else
+          super
+        end
+      end
+    end
+  end
+end
diff --git a/railties/lib/rails/command/behavior.rb b/railties/lib/rails/command/behavior.rb
new file mode 100644
index 0000000000..7a6dd28e1a
--- /dev/null
+++ b/railties/lib/rails/command/behavior.rb
@@ -0,0 +1,125 @@
+# frozen_string_literal: true
+
+require "active_support"
+
+module Rails
+  module Command
+    module Behavior #:nodoc:
+      extend ActiveSupport::Concern
+
+      class_methods do
+        # Remove the color from output.
+        def no_color!
+          Thor::Base.shell = Thor::Shell::Basic
+        end
+
+        # Track all command subclasses.
+        def subclasses
+          @subclasses ||= []
+        end
+
+        private
+
+          # This code is based directly on the Text gem implementation.
+          # Copyright (c) 2006-2013 Paul Battley, Michael Neumann, Tim Fletcher.
+          #
+          # Returns a value representing the "cost" of transforming str1 into str2.
+          def levenshtein_distance(str1, str2) # :doc:
+            s = str1
+            t = str2
+            n = s.length
+            m = t.length
+
+            return m if (0 == n)
+            return n if (0 == m)
+
+            d = (0..m).to_a
+            x = nil
+
+            # avoid duplicating an enumerable object in the loop
+            str2_codepoint_enumerable = str2.each_codepoint
+
+            str1.each_codepoint.with_index do |char1, i|
+              e = i + 1
+
+              str2_codepoint_enumerable.with_index do |char2, j|
+                cost = (char1 == char2) ? 0 : 1
+                x = [
+                     d[j + 1] + 1, # insertion
+                     e + 1,      # deletion
+                     d[j] + cost # substitution
+                    ].min
+                d[j] = e
+                e = x
+              end
+
+              d[m] = x
+            end
+
+            x
+          end
+
+          # Prints a list of generators.
+          def print_list(base, namespaces)
+            return if namespaces.empty?
+            puts "#{base.camelize}:"
+
+            namespaces.each do |namespace|
+              puts("  #{namespace}")
+            end
+
+            puts
+          end
+
+          # Receives namespaces in an array and tries to find matching generators
+          # in the load path.
+          def lookup(namespaces)
+            paths = namespaces_to_paths(namespaces)
+
+            paths.each do |raw_path|
+              lookup_paths.each do |base|
+                path = "#{base}/#{raw_path}_#{command_type}"
+
+                begin
+                  require path
+                  return
+                rescue LoadError => e
+                  raise unless e.message =~ /#{Regexp.escape(path)}$/
+                rescue Exception => e
+                  warn "[WARNING] Could not load #{command_type} #{path.inspect}. Error: #{e.message}.\n#{e.backtrace.join("\n")}"
+                end
+              end
+            end
+          end
+
+          # This will try to load any command in the load path to show in help.
+          def lookup!
+            $LOAD_PATH.each do |base|
+              Dir[File.join(base, *file_lookup_paths)].each do |path|
+                begin
+                  path = path.sub("#{base}/", "")
+                  require path
+                rescue Exception
+                  # No problem
+                end
+              end
+            end
+          end
+
+          # Convert namespaces to paths by replacing ":" for "/" and adding
+          # an extra lookup. For example, "rails:model" should be searched
+          # in both: "rails/model/model_generator" and "rails/model_generator".
+          def namespaces_to_paths(namespaces)
+            paths = []
+            namespaces.each do |namespace|
+              pieces = namespace.split(":")
+              paths << pieces.dup.push(pieces.last).join("/")
+              paths << pieces.join("/")
+            end
+            paths.uniq!
+            paths
+          end
+      end
+    end
+  end
+end
diff --git a/railties/lib/rails/command/environment_argument.rb b/railties/lib/rails/command/environment_argument.rb
new file mode 100644
index 0000000000..5dc98b113d
--- /dev/null
+++ b/railties/lib/rails/command/environment_argument.rb
@@ -0,0 +1,47 @@
+# frozen_string_literal: true
+
+require "active_support"
+
+module Rails
+  module Command
+    module EnvironmentArgument #:nodoc:
+      extend ActiveSupport::Concern
+
+      included do
+        argument :environment, optional: true, banner: "environment"
+
+        class_option :environment, aliases: "-e", type: :string,
+          desc: "Specifies the environment to run this console under (test/development/production)."
+      end
+
+      private
+        def extract_environment_option_from_argument
+          if environment
+            self.options = options.merge(environment: acceptable_environment(environment))
+
+            ActiveSupport::Deprecation.warn "Passing the environment's name as a " \
+                                            "regular argument is deprecated and "  \
+                                            "will be removed in the next Rails "   \
+                                            "version. Please, use the -e option "  \
+                                            "instead."
+          elsif options[:environment]
+            self.options = options.merge(environment: acceptable_environment(options[:environment]))
+          else
+            self.options = options.merge(environment: Rails::Command.environment)
+          end
+        end
+
+        def acceptable_environment(env = nil)
+          if available_environments.include? env
+            env
+          else
+            %w( production development test ).detect { |e| e =~ /^#{env}/ } || env
+          end
+        end
+
+        def available_environments
+          Dir["config/environments/*.rb"].map { |fname| File.basename(fname, ".*") }
+        end
+    end
+  end
+end
diff --git a/railties/lib/rails/command/helpers/editor.rb b/railties/lib/rails/command/helpers/editor.rb
new file mode 100644
index 0000000000..6191d97672
--- /dev/null
+++ b/railties/lib/rails/command/helpers/editor.rb
@@ -0,0 +1,35 @@
+# frozen_string_literal: true
+
+require "active_support/encrypted_file"
+
+module Rails
+  module Command
+    module Helpers
+      module Editor
+        private
+          def ensure_editor_available(command:)
+            if ENV["EDITOR"].to_s.empty?
+              say "No $EDITOR to open file in. Assign one like this:"
+              say ""
+              say %(EDITOR="mate --wait" #{command})
+              say ""
+              say "For editors that fork and exit immediately, it's important to pass a wait flag,"
+              say "otherwise the credentials will be saved immediately with no chance to edit."
+
+              false
+            else
+              true
+            end
+          end
+
+          def catch_editing_exceptions
+            yield
+          rescue Interrupt
+            say "Aborted changing file: nothing saved."
+          rescue ActiveSupport::EncryptedFile::MissingKeyError => error
+            say error.message
+          end
+      end
+    end
+  end
+end
diff --git a/railties/lib/rails/commands.rb b/railties/lib/rails/commands.rb
index 5a66b78a92..77961a0292 100644
--- a/railties/lib/rails/commands.rb
+++ b/railties/lib/rails/commands.rb
@@ -1,4 +1,6 @@
-ARGV << '--help' if ARGV.empty?
+# frozen_string_literal: true
+
+require "rails/command"
 
 aliases = {
   "g"  => "generate",
@@ -13,6 +15,4 @@ aliases = {
 command = ARGV.shift
 command = aliases[command] || command
 
-require 'rails/commands/commands_tasks'
-
-Rails::CommandsTasks.new(ARGV).run_command!(command)
+Rails::Command.invoke command, ARGV
diff --git a/railties/lib/rails/commands/application.rb b/railties/lib/rails/commands/application.rb
deleted file mode 100644
index c998e6b6a8..0000000000
--- a/railties/lib/rails/commands/application.rb
+++ /dev/null
@@ -1,17 +0,0 @@
-require 'rails/generators'
-require 'rails/generators/rails/app/app_generator'
-
-module Rails
-  module Generators
-    class AppGenerator # :nodoc:
-      # We want to exit on failure to be kind to other libraries
-      # This is only when accessing via CLI
-      def self.exit_on_failure?
-        true
-      end
-    end
-  end
-end
-
-args = Rails::Generators::ARGVScrubber.new(ARGV).prepare!
-Rails::Generators::AppGenerator.start args
diff --git a/railties/lib/rails/commands/application/application_command.rb b/railties/lib/rails/commands/application/application_command.rb
new file mode 100644
index 0000000000..f77553b830
--- /dev/null
+++ b/railties/lib/rails/commands/application/application_command.rb
@@ -0,0 +1,31 @@
+# frozen_string_literal: true
+
+require "rails/generators"
+require "rails/generators/rails/app/app_generator"
+
+module Rails
+  module Generators
+    class AppGenerator # :nodoc:
+      # We want to exit on failure to be kind to other libraries
+      # This is only when accessing via CLI
+      def self.exit_on_failure?
+        true
+      end
+    end
+  end
+
+  module Command
+    class ApplicationCommand < Base # :nodoc:
+      hide_command!
+
+      def help
+        perform # Punt help output to the generator.
+      end
+
+      def perform(*args)
+        Rails::Generators::AppGenerator.start \
+          Rails::Generators::ARGVScrubber.new(args).prepare!
+      end
+    end
+  end
+end
diff --git a/railties/lib/rails/commands/commands_tasks.rb b/railties/lib/rails/commands/commands_tasks.rb
deleted file mode 100644
index da3b9452d5..0000000000
--- a/railties/lib/rails/commands/commands_tasks.rb
+++ /dev/null
@@ -1,180 +0,0 @@
-require 'rails/commands/rake_proxy'
-
-module Rails
-  # This is a class which takes in a rails command and initiates the appropriate
-  # initiation sequence.
-  #
-  # Warning: This class mutates ARGV because some commands require manipulating
-  # it before they are run.
-  class CommandsTasks # :nodoc:
-    include Rails::RakeProxy
-
-    attr_reader :argv
-
-    HELP_MESSAGE = <<-EOT
-Usage: rails COMMAND [ARGS]
-
-The most common rails commands are:
- generate    Generate new code (short-cut alias: "g")
- console     Start the Rails console (short-cut alias: "c")
- server      Start the Rails server (short-cut alias: "s")
- test        Run tests (short-cut alias: "t")
- dbconsole   Start a console for the database specified in config/database.yml
-             (short-cut alias: "db")
- new         Create a new Rails application. "rails new my_app" creates a
-             new application called MyApp in "./my_app"
-
-All commands can be run with -h (or --help) for more information.
-
-In addition to those commands, there are:
-EOT
-
-    ADDITIONAL_COMMANDS = [
-      [ 'destroy', 'Undo code generated with "generate" (short-cut alias: "d")' ],
-      [ 'plugin new', 'Generates skeleton for developing a Rails plugin' ],
-      [ 'runner',
-        'Run a piece of code in the application environment (short-cut alias: "r")' ]
-    ]
-
-    COMMAND_WHITELIST = %w(plugin generate destroy console server dbconsole runner new version help test)
-
-    def initialize(argv)
-      @argv = argv
-    end
-
-    def run_command!(command)
-      command = parse_command(command)
-
-      if COMMAND_WHITELIST.include?(command)
-        send(command)
-      else
-        run_rake_task(command)
-      end
-    end
-
-    def plugin
-      require_command!("plugin")
-    end
-
-    def generate
-      generate_or_destroy(:generate)
-    end
-
-    def destroy
-      generate_or_destroy(:destroy)
-    end
-
-    def console
-      require_command!("console")
-      options = Rails::Console.parse_arguments(argv)
-
-      # RAILS_ENV needs to be set before config/application is required
-      ENV['RAILS_ENV'] = options[:environment] if options[:environment]
-
-      # shift ARGV so IRB doesn't freak
-      shift_argv!
-
-      require_application_and_environment!
-      Rails::Console.start(Rails.application, options)
-    end
-
-    def server
-      set_application_directory!
-      require_command!("server")
-
-      Rails::Server.new.tap do |server|
-        # We need to require application after the server sets environment,
-        # otherwise the --environment option given to the server won't propagate.
-        require APP_PATH
-        Dir.chdir(Rails.application.root)
-        server.start
-      end
-    end
-
-    def test
-      require_command!("test")
-    end
-
-    def dbconsole
-      require_command!("dbconsole")
-      Rails::DBConsole.start
-    end
-
-    def runner
-      require_command!("runner")
-    end
-
-    def new
-      if %w(-h --help).include?(argv.first)
-        require_command!("application")
-      else
-        exit_with_initialization_warning!
-      end
-    end
-
-    def version
-      argv.unshift '--version'
-      require_command!("application")
-    end
-
-    def help
-      write_help_message
-      write_commands ADDITIONAL_COMMANDS + formatted_rake_tasks
-    end
-
-    private
-
-      def exit_with_initialization_warning!
-        puts "Can't initialize a new Rails application within the directory of another, please change to a non-Rails directory first.\n"
-        puts "Type 'rails' for help."
-        exit(1)
-      end
-
-      def shift_argv!
-        argv.shift if argv.first && argv.first[0] != '-'
-      end
-
-      def require_command!(command)
-        require "rails/commands/#{command}"
-      end
-
-      def generate_or_destroy(command)
-        require 'rails/generators'
-        require_application_and_environment!
-        Rails.application.load_generators
-        require_command!(command)
-      end
-
-      # Change to the application's path if there is no config.ru file in current directory.
-      # This allows us to run `rails server` from other directories, but still get
-      # the main config.ru and properly set the tmp directory.
-      def set_application_directory!
-        Dir.chdir(File.expand_path('../../', APP_PATH)) unless File.exist?(File.expand_path("config.ru"))
-      end
-
-      def require_application_and_environment!
-        require APP_PATH
-        Rails.application.require_environment!
-      end
-
-      def write_help_message
-        puts HELP_MESSAGE
-      end
-
-      def write_commands(commands)
-        width = commands.map { |name, _| name.size }.max || 10
-        commands.each { |command| printf(" %-#{width}s   %s\n", *command) }
-      end
-
-      def parse_command(command)
-        case command
-        when '--version', '-v'
-          'version'
-        when '--help', '-h'
-          'help'
-        else
-          command
-        end
-      end
-  end
-end
diff --git a/railties/lib/rails/commands/console.rb b/railties/lib/rails/commands/console.rb
deleted file mode 100644
index ea5d20ea24..0000000000
--- a/railties/lib/rails/commands/console.rb
+++ /dev/null
@@ -1,68 +0,0 @@
-require 'optparse'
-require 'irb'
-require 'irb/completion'
-require 'rails/commands/console_helper'
-
-module Rails
-  class Console
-    include ConsoleHelper
-
-    class << self
-      def parse_arguments(arguments)
-        options = {}
-
-        OptionParser.new do |opt|
-          opt.banner = "Usage: rails console [environment] [options]"
-          opt.on('-s', '--sandbox', 'Rollback database modifications on exit.') { |v| options[:sandbox] = v }
-          opt.on("-e", "--environment=name", String,
-                  "Specifies the environment to run this console under (test/development/production).",
-                  "Default: development") { |v| options[:environment] = v.strip }
-          opt.parse!(arguments)
-        end
-
-        set_options_env(arguments, options)
-      end
-    end
-
-    attr_reader :options, :app, :console
-
-    def initialize(app, options={})
-      @app     = app
-      @options = options
-
-      app.sandbox = sandbox?
-      app.load_console
-
-      @console = app.config.console || IRB
-    end
-
-    def sandbox?
-      options[:sandbox]
-    end
-
-    def environment
-      options[:environment] ||= super
-    end
-    alias_method :environment?, :environment
-
-    def set_environment!
-      Rails.env = environment
-    end
-
-    def start
-      set_environment! if environment?
-
-      if sandbox?
-        puts "Loading #{Rails.env} environment in sandbox (Rails #{Rails.version})"
-        puts "Any modifications you make will be rolled back on exit"
-      else
-        puts "Loading #{Rails.env} environment (Rails #{Rails.version})"
-      end
-
-      if defined?(console::ExtendCommandBundle)
-        console::ExtendCommandBundle.include(Rails::ConsoleMethods)
-      end
-      console.start
-    end
-  end
-end
diff --git a/railties/lib/rails/commands/console/console_command.rb b/railties/lib/rails/commands/console/console_command.rb
new file mode 100644
index 0000000000..e35faa5b01
--- /dev/null
+++ b/railties/lib/rails/commands/console/console_command.rb
@@ -0,0 +1,100 @@
+# frozen_string_literal: true
+
+require "irb"
+require "irb/completion"
+
+require "rails/command/environment_argument"
+
+module Rails
+  class Console
+    module BacktraceCleaner
+      def filter_backtrace(bt)
+        if result = super
+          Rails.backtrace_cleaner.filter([result]).first
+        end
+      end
+    end
+
+    def self.start(*args)
+      new(*args).start
+    end
+
+    attr_reader :options, :app, :console
+
+    def initialize(app, options = {})
+      @app     = app
+      @options = options
+
+      app.sandbox = sandbox?
+      app.load_console
+
+      @console = app.config.console || IRB
+
+      if @console == IRB
+        IRB::WorkSpace.prepend(BacktraceCleaner)
+      end
+    end
+
+    def sandbox?
+      options[:sandbox]
+    end
+
+    def environment
+      options[:environment]
+    end
+    alias_method :environment?, :environment
+
+    def set_environment!
+      Rails.env = environment
+    end
+
+    def start
+      set_environment! if environment?
+
+      if sandbox?
+        puts "Loading #{Rails.env} environment in sandbox (Rails #{Rails.version})"
+        puts "Any modifications you make will be rolled back on exit"
+      else
+        puts "Loading #{Rails.env} environment (Rails #{Rails.version})"
+      end
+
+      if defined?(console::ExtendCommandBundle)
+        console::ExtendCommandBundle.include(Rails::ConsoleMethods)
+      end
+      console.start
+    end
+  end
+
+  module Command
+    class ConsoleCommand < Base # :nodoc:
+      include EnvironmentArgument
+
+      class_option :sandbox, aliases: "-s", type: :boolean, default: false,
+        desc: "Rollback database modifications on exit."
+
+      def initialize(args = [], local_options = {}, config = {})
+        console_options = []
+
+        # For the same behavior as OptionParser, leave only options after "--" in ARGV.
+        termination = local_options.find_index("--")
+        if termination
+          console_options = local_options[termination + 1..-1]
+          local_options = local_options[0...termination]
+        end
+
+        ARGV.replace(console_options)
+        super(args, local_options, config)
+      end
+
+      def perform
+        extract_environment_option_from_argument
+
+        # RAILS_ENV needs to be set before config/application is required.
+        ENV["RAILS_ENV"] = options[:environment]
+
+        require_application_and_environment!
+        Rails::Console.start(Rails.application, options)
+      end
+    end
+  end
+end
diff --git a/railties/lib/rails/commands/console_helper.rb b/railties/lib/rails/commands/console_helper.rb
deleted file mode 100644
index 8ee0b60012..0000000000
--- a/railties/lib/rails/commands/console_helper.rb
+++ /dev/null
@@ -1,34 +0,0 @@
-require 'active_support/concern'
-
-module Rails
-  module ConsoleHelper # :nodoc:
-    extend ActiveSupport::Concern
-
-    module ClassMethods
-      def start(*args)
-        new(*args).start
-      end
-      
-      private
-        def set_options_env(arguments, options)
-          if arguments.first && arguments.first[0] != '-'
-            env = arguments.first
-            if available_environments.include? env
-              options[:environment] = env
-            else
-              options[:environment] = %w(production development test).detect { |e| e =~ /^#{env}/ } || env
-            end
-          end
-          options
-        end
-
-        def available_environments
-          Dir['config/environments/*.rb'].map { |fname| File.basename(fname, '.*') }
-        end  
-    end
-
-    def environment
-      ENV["RAILS_ENV"] || ENV["RACK_ENV"] || "development"
-    end
-  end
-end
\ No newline at end of file
diff --git a/railties/lib/rails/commands/credentials/USAGE b/railties/lib/rails/commands/credentials/USAGE
new file mode 100644
index 0000000000..85877c71b7
--- /dev/null
+++ b/railties/lib/rails/commands/credentials/USAGE
@@ -0,0 +1,40 @@
+=== Storing Encrypted Credentials in Source Control
+
+The Rails `credentials` commands provide access to encrypted credentials,
+so you can safely store access tokens, database passwords, and the like
+safely inside the app without relying on a mess of ENVs.
+
+This also allows for atomic deploys: no need to coordinate key changes
+to get everything working as the keys are shipped with the code.
+
+=== Setup
+
+Applications after Rails 5.2 automatically have a basic credentials file generated
+that just contains the secret_key_base used by MessageVerifiers/MessageEncryptors, like the ones
+signing and encrypting cookies.
+
+For applications created prior to Rails 5.2, we'll automatically generate a new
+credentials file in `config/credentials.yml.enc` the first time you run `bin/rails credentials:edit`.
+If you didn't have a master key saved in `config/master.key`, that'll be created too.
+
+Don't lose this master key! Put it in a password manager your team can access.
+Should you lose it no one, including you, will be able to access any encrypted
+credentials.
+
+Don't commit the key! Add `config/master.key` to your source control's
+ignore file. If you use Git, Rails handles this for you.
+
+Rails also looks for the master key in `ENV["RAILS_MASTER_KEY"]`, if that's easier to manage.
+
+You could prepend that to your server's start command like this:
+
+   RAILS_MASTER_KEY="very-secret-and-secure" server.start
+
+=== Editing Credentials
+
+This will open a temporary file in `$EDITOR` with the decrypted contents to edit
+the encrypted credentials.
+
+When the temporary file is next saved the contents are encrypted and written to
+`config/credentials.yml.enc` while the file itself is destroyed to prevent credentials
+from leaking.
diff --git a/railties/lib/rails/commands/credentials/credentials_command.rb b/railties/lib/rails/commands/credentials/credentials_command.rb
new file mode 100644
index 0000000000..385d3976da
--- /dev/null
+++ b/railties/lib/rails/commands/credentials/credentials_command.rb
@@ -0,0 +1,79 @@
+# frozen_string_literal: true
+
+require "active_support"
+require "rails/command/helpers/editor"
+
+module Rails
+  module Command
+    class CredentialsCommand < Rails::Command::Base # :nodoc:
+      include Helpers::Editor
+
+      no_commands do
+        def help
+          say "Usage:\n  #{self.class.banner}"
+          say ""
+          say self.class.desc
+        end
+      end
+
+      def edit
+        require_application_and_environment!
+
+        ensure_editor_available(command: "bin/rails credentials:edit") || (return)
+        ensure_master_key_has_been_added
+        ensure_credentials_have_been_added
+
+        catch_editing_exceptions do
+          change_credentials_in_system_editor
+        end
+
+        say "New credentials encrypted and saved."
+      end
+
+      def show
+        require_application_and_environment!
+
+        say Rails.application.credentials.read.presence || missing_credentials_message
+      end
+
+      private
+        def ensure_master_key_has_been_added
+          master_key_generator.add_master_key_file
+          master_key_generator.ignore_master_key_file
+        end
+
+        def ensure_credentials_have_been_added
+          credentials_generator.add_credentials_file_silently
+        end
+
+        def change_credentials_in_system_editor
+          Rails.application.credentials.change do |tmp_path|
+            system("#{ENV["EDITOR"]} #{tmp_path}")
+          end
+        end
+
+
+        def master_key_generator
+          require "rails/generators"
+          require "rails/generators/rails/master_key/master_key_generator"
+
+          Rails::Generators::MasterKeyGenerator.new
+        end
+
+        def credentials_generator
+          require "rails/generators"
+          require "rails/generators/rails/credentials/credentials_generator"
+
+          Rails::Generators::CredentialsGenerator.new
+        end
+
+        def missing_credentials_message
+          if Rails.application.credentials.key.nil?
+            "Missing master key to decrypt credentials. See bin/rails credentials:help"
+          else
+            "No credentials have been added yet. Use bin/rails credentials:edit to change that."
+          end
+        end
+    end
+  end
+end
diff --git a/railties/lib/rails/commands/dbconsole.rb b/railties/lib/rails/commands/dbconsole.rb
deleted file mode 100644
index 2c36edfa3f..0000000000
--- a/railties/lib/rails/commands/dbconsole.rb
+++ /dev/null
@@ -1,173 +0,0 @@
-require 'erb'
-require 'yaml'
-require 'optparse'
-require 'rails/commands/console_helper'
-
-module Rails
-  class DBConsole
-    include ConsoleHelper
-
-    attr_reader :arguments
-
-    class << self
-      def parse_arguments(arguments)
-        options = {}
-
-        OptionParser.new do |opt|
-          opt.banner = "Usage: rails dbconsole [environment] [options]"
-          opt.on("-p", "--include-password", "Automatically provide the password from database.yml") do |v|
-            options['include_password'] = true
-          end
-
-          opt.on("--mode [MODE]", ['html', 'list', 'line', 'column'],
-            "Automatically put the sqlite3 database in the specified mode (html, list, line, column).") do |mode|
-              options['mode'] = mode
-          end
-
-          opt.on("--header") do |h|
-            options['header'] = h
-          end
-
-          opt.on("-h", "--help", "Show this help message.") do
-            puts opt
-            exit
-          end
-
-          opt.on("-e", "--environment=name", String,
-            "Specifies the environment to run this console under (test/development/production).",
-            "Default: development"
-          ) { |v| options[:environment] = v.strip }
-
-          opt.parse!(arguments)
-          abort opt.to_s unless (0..1).include?(arguments.size)
-        end
-
-        set_options_env(arguments, options)
-      end
-    end
-
-    def initialize(arguments = ARGV)
-      @arguments = arguments
-    end
-
-    def start
-      options = self.class.parse_arguments(arguments)
-      ENV['RAILS_ENV'] = options[:environment] || environment
-
-      case config["adapter"]
-      when /^(jdbc)?mysql/
-        args = {
-          'host'      => '--host',
-          'port'      => '--port',
-          'socket'    => '--socket',
-          'username'  => '--user',
-          'encoding'  => '--default-character-set',
-          'sslca'     => '--ssl-ca',
-          'sslcert'   => '--ssl-cert',
-          'sslcapath' => '--ssl-capath',
-          'sslcipher' => '--ssl-cipher',
-          'sslkey'    => '--ssl-key'
-        }.map { |opt, arg| "#{arg}=#{config[opt]}" if config[opt] }.compact
-
-        if config['password'] && options['include_password']
-          args << "--password=#{config['password']}"
-        elsif config['password'] && !config['password'].to_s.empty?
-          args << "-p"
-        end
-
-        args << config['database']
-
-        find_cmd_and_exec(['mysql', 'mysql5'], *args)
-
-      when /^postgres|^postgis/
-        ENV['PGUSER']     = config["username"] if config["username"]
-        ENV['PGHOST']     = config["host"] if config["host"]
-        ENV['PGPORT']     = config["port"].to_s if config["port"]
-        ENV['PGPASSWORD'] = config["password"].to_s if config["password"] && options['include_password']
-        find_cmd_and_exec('psql', config["database"])
-
-      when "sqlite3"
-        args = []
-
-        args << "-#{options['mode']}" if options['mode']
-        args << "-header" if options['header']
-        args << File.expand_path(config['database'], Rails.respond_to?(:root) ? Rails.root : nil)
-
-        find_cmd_and_exec('sqlite3', *args)
-
-      when "oracle", "oracle_enhanced"
-        logon = ""
-
-        if config['username']
-          logon = config['username']
-          logon << "/#{config['password']}" if config['password'] && options['include_password']
-          logon << "@#{config['database']}" if config['database']
-        end
-
-        find_cmd_and_exec('sqlplus', logon)
-
-      when "sqlserver"
-        args = []
-
-        args += ["-D", "#{config['database']}"] if config['database']
-        args += ["-U", "#{config['username']}"] if config['username']
-        args += ["-P", "#{config['password']}"] if config['password']
-
-        if config['host']
-          host_arg = "#{config['host']}"
-          host_arg << ":#{config['port']}" if config['port']
-          args += ["-S", host_arg]
-        end
-
-        find_cmd_and_exec("sqsh", *args)
-
-      else
-        abort "Unknown command-line client for #{config['database']}."
-      end
-    end
-
-    def config
-      @config ||= begin
-        if configurations[environment].blank?
-          raise ActiveRecord::AdapterNotSpecified, "'#{environment}' database is not configured. Available configuration: #{configurations.inspect}"
-        else
-          configurations[environment]
-        end
-      end
-    end
-
-    def environment
-      Rails.respond_to?(:env) ? Rails.env : super
-    end
-
-    protected
-      def configurations
-        require APP_PATH
-        ActiveRecord::Base.configurations = Rails.application.config.database_configuration
-        ActiveRecord::Base.configurations
-      end
-
-      def find_cmd_and_exec(commands, *args)
-        commands = Array(commands)
-
-        dirs_on_path = ENV['PATH'].to_s.split(File::PATH_SEPARATOR)
-        unless (ext = RbConfig::CONFIG['EXEEXT']).empty?
-          commands = commands.map{|cmd| "#{cmd}#{ext}"}
-        end
-
-        full_path_command = nil
-        found = commands.detect do |cmd|
-          dirs_on_path.detect do |path|
-            full_path_command = File.join(path, cmd)
-            File.file?(full_path_command) && File.executable?(full_path_command)
-          end
-        end
-
-        if found
-          exec full_path_command, *args
-        else
-          abort("Couldn't find database client: #{commands.join(', ')}. Check your $PATH and try again.")
-        end
-      end
-  end
-end
diff --git a/railties/lib/rails/commands/dbconsole/dbconsole_command.rb b/railties/lib/rails/commands/dbconsole/dbconsole_command.rb
new file mode 100644
index 0000000000..8df548b5de
--- /dev/null
+++ b/railties/lib/rails/commands/dbconsole/dbconsole_command.rb
@@ -0,0 +1,170 @@
+# frozen_string_literal: true
+
+require "rails/command/environment_argument"
+
+module Rails
+  class DBConsole
+    def self.start(*args)
+      new(*args).start
+    end
+
+    def initialize(options = {})
+      @options = options
+    end
+
+    def start
+      ENV["RAILS_ENV"] ||= @options[:environment] || environment
+
+      case config["adapter"]
+      when /^(jdbc)?mysql/
+        args = {
+          "host"      => "--host",
+          "port"      => "--port",
+          "socket"    => "--socket",
+          "username"  => "--user",
+          "encoding"  => "--default-character-set",
+          "sslca"     => "--ssl-ca",
+          "sslcert"   => "--ssl-cert",
+          "sslcapath" => "--ssl-capath",
+          "sslcipher" => "--ssl-cipher",
+          "sslkey"    => "--ssl-key"
+        }.map { |opt, arg| "#{arg}=#{config[opt]}" if config[opt] }.compact
+
+        if config["password"] && @options["include_password"]
+          args << "--password=#{config['password']}"
+        elsif config["password"] && !config["password"].to_s.empty?
+          args << "-p"
+        end
+
+        args << config["database"]
+
+        find_cmd_and_exec(["mysql", "mysql5"], *args)
+
+      when /^postgres|^postgis/
+        ENV["PGUSER"]     = config["username"] if config["username"]
+        ENV["PGHOST"]     = config["host"] if config["host"]
+        ENV["PGPORT"]     = config["port"].to_s if config["port"]
+        ENV["PGPASSWORD"] = config["password"].to_s if config["password"] && @options["include_password"]
+        find_cmd_and_exec("psql", config["database"])
+
+      when "sqlite3"
+        args = []
+
+        args << "-#{@options['mode']}" if @options["mode"]
+        args << "-header" if @options["header"]
+        args << File.expand_path(config["database"], Rails.respond_to?(:root) ? Rails.root : nil)
+
+        find_cmd_and_exec("sqlite3", *args)
+
+      when "oracle", "oracle_enhanced"
+        logon = ""
+
+        if config["username"]
+          logon = config["username"].dup
+          logon << "/#{config['password']}" if config["password"] && @options["include_password"]
+          logon << "@#{config['database']}" if config["database"]
+        end
+
+        find_cmd_and_exec("sqlplus", logon)
+
+      when "sqlserver"
+        args = []
+
+        args += ["-D", "#{config['database']}"] if config["database"]
+        args += ["-U", "#{config['username']}"] if config["username"]
+        args += ["-P", "#{config['password']}"] if config["password"]
+
+        if config["host"]
+          host_arg = "#{config['host']}".dup
+          host_arg << ":#{config['port']}" if config["port"]
+          args += ["-S", host_arg]
+        end
+
+        find_cmd_and_exec("sqsh", *args)
+
+      else
+        abort "Unknown command-line client for #{config['database']}."
+      end
+    end
+
+    def config
+      @config ||= begin
+        # We need to check whether the user passed the connection the
+        # first time around to show a consistent error message to people
+        # relying on 2-level database configuration.
+        if @options["connection"] && configurations[connection].blank?
+          raise ActiveRecord::AdapterNotSpecified, "'#{connection}' connection is not configured. Available configuration: #{configurations.inspect}"
+        elsif configurations[environment].blank? && configurations[connection].blank?
+          raise ActiveRecord::AdapterNotSpecified, "'#{environment}' database is not configured. Available configuration: #{configurations.inspect}"
+        else
+          configurations[environment].presence || configurations[connection]
+        end
+      end
+    end
+
+    def environment
+      Rails.respond_to?(:env) ? Rails.env : Rails::Command.environment
+    end
+
+    def connection
+      @options.fetch(:connection, "primary")
+    end
+
+    private
+      def configurations # :doc:
+        require APP_PATH
+        ActiveRecord::Base.configurations = Rails.application.config.database_configuration
+        ActiveRecord::Base.configurations
+      end
+
+      def find_cmd_and_exec(commands, *args) # :doc:
+        commands = Array(commands)
+
+        dirs_on_path = ENV["PATH"].to_s.split(File::PATH_SEPARATOR)
+        unless (ext = RbConfig::CONFIG["EXEEXT"]).empty?
+          commands = commands.map { |cmd| "#{cmd}#{ext}" }
+        end
+
+        full_path_command = nil
+        found = commands.detect do |cmd|
+          dirs_on_path.detect do |path|
+            full_path_command = File.join(path, cmd)
+            File.file?(full_path_command) && File.executable?(full_path_command)
+          end
+        end
+
+        if found
+          exec full_path_command, *args
+        else
+          abort("Couldn't find database client: #{commands.join(', ')}. Check your $PATH and try again.")
+        end
+      end
+  end
+
+  module Command
+    class DbconsoleCommand < Base # :nodoc:
+      include EnvironmentArgument
+
+      class_option :include_password, aliases: "-p", type: :boolean,
+        desc: "Automatically provide the password from database.yml"
+
+      class_option :mode, enum: %w( html list line column ), type: :string,
+        desc: "Automatically put the sqlite3 database in the specified mode (html, list, line, column)."
+
+      class_option :header, type: :boolean
+
+      class_option :connection, aliases: "-c", type: :string,
+        desc: "Specifies the connection to use."
+
+      def perform
+        extract_environment_option_from_argument
+
+        # RAILS_ENV needs to be set before config/application is required.
+        ENV["RAILS_ENV"] = options[:environment]
+
+        require_application_and_environment!
+        Rails::DBConsole.start(options)
+      end
+    end
+  end
+end
diff --git a/railties/lib/rails/commands/destroy.rb b/railties/lib/rails/commands/destroy.rb
deleted file mode 100644
index ce26cc3fde..0000000000
--- a/railties/lib/rails/commands/destroy.rb
+++ /dev/null
@@ -1,11 +0,0 @@
-require 'rails/generators'
-
-#if no argument/-h/--help is passed to rails destroy command, then
-#it generates the help associated.
-if [nil, "-h", "--help"].include?(ARGV.first)
-  Rails::Generators.help 'destroy'
-  exit
-end
-
-name = ARGV.shift
-Rails::Generators.invoke name, ARGV, behavior: :revoke, destination_root: Rails.root
diff --git a/railties/lib/rails/commands/destroy/destroy_command.rb b/railties/lib/rails/commands/destroy/destroy_command.rb
new file mode 100644
index 0000000000..dd432d28fd
--- /dev/null
+++ b/railties/lib/rails/commands/destroy/destroy_command.rb
@@ -0,0 +1,28 @@
+# frozen_string_literal: true
+
+require "rails/generators"
+
+module Rails
+  module Command
+    class DestroyCommand < Base # :nodoc:
+      no_commands do
+        def help
+          require_application_and_environment!
+          load_generators
+
+          Rails::Generators.help self.class.command_name
+        end
+      end
+
+      def perform(*)
+        generator = args.shift
+        return help unless generator
+
+        require_application_and_environment!
+        load_generators
+
+        Rails::Generators.invoke generator, args, behavior: :revoke, destination_root: Rails::Command.root
+      end
+    end
+  end
+end
diff --git a/railties/lib/rails/commands/encrypted/encrypted_command.rb b/railties/lib/rails/commands/encrypted/encrypted_command.rb
new file mode 100644
index 0000000000..912c453f09
--- /dev/null
+++ b/railties/lib/rails/commands/encrypted/encrypted_command.rb
@@ -0,0 +1,85 @@
+# frozen_string_literal: true
+
+require "pathname"
+require "active_support"
+require "rails/command/helpers/editor"
+
+module Rails
+  module Command
+    class EncryptedCommand < Rails::Command::Base # :nodoc:
+      include Helpers::Editor
+
+      class_option :key, aliases: "-k", type: :string,
+        default: "config/master.key", desc: "The Rails.root relative path to the encryption key"
+
+      no_commands do
+        def help
+          say "Usage:\n  #{self.class.banner}"
+          say ""
+        end
+      end
+
+      def edit(file_path)
+        require_application_and_environment!
+
+        ensure_editor_available(command: "bin/rails encrypted:edit") || (return)
+        ensure_encryption_key_has_been_added(options[:key])
+        ensure_encrypted_file_has_been_added(file_path, options[:key])
+
+        catch_editing_exceptions do
+          change_encrypted_file_in_system_editor(file_path, options[:key])
+        end
+
+        say "File encrypted and saved."
+      rescue ActiveSupport::MessageEncryptor::InvalidMessage
+        say "Couldn't decrypt #{file_path}. Perhaps you passed the wrong key?"
+      end
+
+      def show(file_path)
+        require_application_and_environment!
+        encrypted = Rails.application.encrypted(file_path, key_path: options[:key])
+
+        say encrypted.read.presence || missing_encrypted_message(key: encrypted.key, key_path: options[:key], file_path: file_path)
+      end
+
+      private
+        def ensure_encryption_key_has_been_added(key_path)
+          encryption_key_file_generator.add_key_file(key_path)
+          encryption_key_file_generator.ignore_key_file(key_path)
+        end
+
+        def ensure_encrypted_file_has_been_added(file_path, key_path)
+          encrypted_file_generator.add_encrypted_file_silently(file_path, key_path)
+        end
+
+        def change_encrypted_file_in_system_editor(file_path, key_path)
+          Rails.application.encrypted(file_path, key_path: key_path).change do |tmp_path|
+            system("#{ENV["EDITOR"]} #{tmp_path}")
+          end
+        end
+
+
+        def encryption_key_file_generator
+          require "rails/generators"
+          require "rails/generators/rails/encryption_key_file/encryption_key_file_generator"
+
+          Rails::Generators::EncryptionKeyFileGenerator.new
+        end
+
+        def encrypted_file_generator
+          require "rails/generators"
+          require "rails/generators/rails/encrypted_file/encrypted_file_generator"
+
+          Rails::Generators::EncryptedFileGenerator.new
+        end
+
+        def missing_encrypted_message(key:, key_path:, file_path:)
+          if key.nil?
+            "Missing '#{key_path}' to decrypt data. See bin/rails encrypted:help"
+          else
+            "File '#{file_path}' does not exist. Use bin/rails encrypted:edit #{file_path} to change that."
+          end
+        end
+    end
+  end
+end
diff --git a/railties/lib/rails/commands/generate.rb b/railties/lib/rails/commands/generate.rb
deleted file mode 100644
index 926c36b967..0000000000
--- a/railties/lib/rails/commands/generate.rb
+++ /dev/null
@@ -1,13 +0,0 @@
-require 'rails/generators'
-
-#if no argument/-h/--help is passed to rails generate command, then
-#it generates the help associated.
-if [nil, "-h", "--help"].include?(ARGV.first)
-  Rails::Generators.help 'generate'
-  exit
-end
-
-name = ARGV.shift
-
-root = defined?(ENGINE_ROOT) ? ENGINE_ROOT : Rails.root
-Rails::Generators.invoke name, ARGV, behavior: :invoke, destination_root: root
diff --git a/railties/lib/rails/commands/generate/generate_command.rb b/railties/lib/rails/commands/generate/generate_command.rb
new file mode 100644
index 0000000000..93d7a0ce3a
--- /dev/null
+++ b/railties/lib/rails/commands/generate/generate_command.rb
@@ -0,0 +1,30 @@
+# frozen_string_literal: true
+
+require "rails/generators"
+
+module Rails
+  module Command
+    class GenerateCommand < Base # :nodoc:
+      no_commands do
+        def help
+          require_application_and_environment!
+          load_generators
+
+          Rails::Generators.help self.class.command_name
+        end
+      end
+
+      def perform(*)
+        generator = args.shift
+        return help unless generator
+
+        require_application_and_environment!
+        load_generators
+
+        ARGV.shift
+
+        Rails::Generators.invoke generator, args, behavior: :invoke, destination_root: Rails::Command.root
+      end
+    end
+  end
+end
diff --git a/railties/lib/rails/commands/help/USAGE b/railties/lib/rails/commands/help/USAGE
new file mode 100644
index 0000000000..8eb98319d2
--- /dev/null
+++ b/railties/lib/rails/commands/help/USAGE
@@ -0,0 +1,16 @@
+The most common rails commands are:
+ generate     Generate new code (short-cut alias: "g")
+ console      Start the Rails console (short-cut alias: "c")
+ server       Start the Rails server (short-cut alias: "s")
+ test         Run tests except system tests (short-cut alias: "t")
+ test:system  Run system tests
+ dbconsole    Start a console for the database specified in config/database.yml
+              (short-cut alias: "db")
+<% unless engine? %>
+ new          Create a new Rails application. "rails new my_app" creates a
+              new application called MyApp in "./my_app"
+<% end %>
+
+All commands can be run with -h (or --help) for more information.
+In addition to those commands, there are:
+
diff --git a/railties/lib/rails/commands/help/help_command.rb b/railties/lib/rails/commands/help/help_command.rb
new file mode 100644
index 0000000000..8e5b4d68d3
--- /dev/null
+++ b/railties/lib/rails/commands/help/help_command.rb
@@ -0,0 +1,15 @@
+# frozen_string_literal: true
+
+module Rails
+  module Command
+    class HelpCommand < Base # :nodoc:
+      hide_command!
+
+      def help(*)
+        puts self.class.desc
+
+        Rails::Command.print_commands
+      end
+    end
+  end
+end
diff --git a/railties/lib/rails/commands/new/new_command.rb b/railties/lib/rails/commands/new/new_command.rb
new file mode 100644
index 0000000000..d73d64d899
--- /dev/null
+++ b/railties/lib/rails/commands/new/new_command.rb
@@ -0,0 +1,19 @@
+# frozen_string_literal: true
+
+module Rails
+  module Command
+    class NewCommand < Base # :nodoc:
+      no_commands do
+        def help
+          Rails::Command.invoke :application, [ "--help" ]
+        end
+      end
+
+      def perform(*)
+        puts "Can't initialize a new Rails application within the directory of another, please change to a non-Rails directory first.\n"
+        puts "Type 'rails' for help."
+        exit 1
+      end
+    end
+  end
+end
diff --git a/railties/lib/rails/commands/plugin.rb b/railties/lib/rails/commands/plugin.rb
deleted file mode 100644
index 52d8966ead..0000000000
--- a/railties/lib/rails/commands/plugin.rb
+++ /dev/null
@@ -1,23 +0,0 @@
-if ARGV.first != "new"
-  ARGV[0] = "--help"
-else
-  ARGV.shift
-  unless ARGV.delete("--no-rc")
-    customrc = ARGV.index{ |x| x.include?("--rc=") }
-    railsrc = if customrc
-                File.expand_path(ARGV.delete_at(customrc).gsub(/--rc=/, ""))
-              else
-                File.join(File.expand_path("~"), '.railsrc')
-              end
-    if File.exist?(railsrc)
-      extra_args_string = File.read(railsrc)
-      extra_args = extra_args_string.split(/\n+/).flat_map(&:split)
-      puts "Using #{extra_args.join(" ")} from #{railsrc}"
-      ARGV.insert(1, *extra_args)
-    end
-  end
-end
-
-require 'rails/generators'
-require 'rails/generators/rails/plugin/plugin_generator'
-Rails::Generators::PluginGenerator.start
diff --git a/railties/lib/rails/commands/plugin/plugin_command.rb b/railties/lib/rails/commands/plugin/plugin_command.rb
new file mode 100644
index 0000000000..2b192abf9b
--- /dev/null
+++ b/railties/lib/rails/commands/plugin/plugin_command.rb
@@ -0,0 +1,45 @@
+# frozen_string_literal: true
+
+module Rails
+  module Command
+    class PluginCommand < Base # :nodoc:
+      hide_command!
+
+      def help
+        run_plugin_generator %w( --help )
+      end
+
+      def self.banner(*) # :nodoc:
+        "#{executable} new [options]"
+      end
+
+      class_option :rc, type: :string, default: File.join("~", ".railsrc"),
+        desc: "Initialize the plugin command with previous defaults. Uses .railsrc in your home directory by default."
+
+      class_option :no_rc, desc: "Skip evaluating .railsrc."
+
+      def perform(type = nil, *plugin_args)
+        plugin_args << "--help" unless type == "new"
+
+        unless options.key?("no_rc") # Thor's not so indifferent access hash.
+          railsrc = File.expand_path(options[:rc])
+
+          if File.exist?(railsrc)
+            extra_args = File.read(railsrc).split(/\n+/).flat_map(&:split)
+            puts "Using #{extra_args.join(" ")} from #{railsrc}"
+            plugin_args.insert(1, *extra_args)
+          end
+        end
+
+        run_plugin_generator plugin_args
+      end
+
+      private
+        def run_plugin_generator(plugin_args)
+          require "rails/generators"
+          require "rails/generators/rails/plugin/plugin_generator"
+          Rails::Generators::PluginGenerator.start plugin_args
+        end
+    end
+  end
+end
diff --git a/railties/lib/rails/commands/rake/rake_command.rb b/railties/lib/rails/commands/rake/rake_command.rb
new file mode 100644
index 0000000000..535df0c430
--- /dev/null
+++ b/railties/lib/rails/commands/rake/rake_command.rb
@@ -0,0 +1,51 @@
+# frozen_string_literal: true
+
+module Rails
+  module Command
+    class RakeCommand < Base # :nodoc:
+      extend Rails::Command::Actions
+
+      namespace "rake"
+
+      class << self
+        def printing_commands
+          formatted_rake_tasks.map(&:first)
+        end
+
+        def perform(task, *)
+          require_rake
+
+          ARGV.unshift(task) # Prepend the task, so Rake knows how to run it.
+
+          Rake.application.standard_exception_handling do
+            Rake.application.init("rails")
+            Rake.application.load_rakefile
+            Rake.application.top_level
+          end
+        end
+
+        private
+          def rake_tasks
+            require_rake
+
+            return @rake_tasks if defined?(@rake_tasks)
+
+            require_application_and_environment!
+
+            Rake::TaskManager.record_task_metadata = true
+            Rake.application.instance_variable_set(:@name, "rails")
+            load_tasks
+            @rake_tasks = Rake.application.tasks.select(&:comment)
+          end
+
+          def formatted_rake_tasks
+            rake_tasks.map { |t| [ t.name_with_args, t.comment ] }
+          end
+
+          def require_rake
+            require "rake" # Defer booting Rake until we know it's needed.
+          end
+      end
+    end
+  end
+end
diff --git a/railties/lib/rails/commands/rake_proxy.rb b/railties/lib/rails/commands/rake_proxy.rb
deleted file mode 100644
index f7d5df6b2f..0000000000
--- a/railties/lib/rails/commands/rake_proxy.rb
+++ /dev/null
@@ -1,34 +0,0 @@
-require 'rake'
-require 'active_support'
-
-module Rails
-  module RakeProxy #:nodoc:
-    private
-      def run_rake_task(command)
-        ARGV.unshift(command) # Prepend the command, so Rake knows how to run it.
-
-        Rake.application.standard_exception_handling do
-          Rake.application.init('rails')
-          Rake.application.load_rakefile
-          Rake.application.top_level
-        end
-      end
-
-      def rake_tasks
-        return @rake_tasks if defined?(@rake_tasks)
-
-        ActiveSupport::Deprecation.silence do
-          require_application_and_environment!
-        end
-
-        Rake::TaskManager.record_task_metadata = true
-        Rake.application.instance_variable_set(:@name, 'rails')
-        Rails.application.load_tasks
-        @rake_tasks = Rake.application.tasks.select(&:comment)
-      end
-
-      def formatted_rake_tasks
-        rake_tasks.map { |t| [ t.name_with_args, t.comment ] }
-      end
-  end
-end
diff --git a/railties/lib/rails/commands/runner.rb b/railties/lib/rails/commands/runner.rb
deleted file mode 100644
index f9c183ac86..0000000000
--- a/railties/lib/rails/commands/runner.rb
+++ /dev/null
@@ -1,69 +0,0 @@
-require 'optparse'
-
-options = { environment: (ENV['RAILS_ENV'] || ENV['RACK_ENV'] || "development").dup }
-code_or_file = nil
-command = 'bin/rails runner'
-
-if ARGV.first.nil?
-  ARGV.push "-h"
-end
-
-ARGV.clone.options do |opts|
-  opts.banner = "Usage: rails runner [options] [<'Some.ruby(code)'> | <filename.rb>]"
-
-  opts.separator ""
-
-  opts.on("-e", "--environment=name", String,
-          "Specifies the environment for the runner to operate under (test/development/production).",
-          "Default: development") { |v| options[:environment] = v }
-
-  opts.separator ""
-
-  opts.on("-h", "--help",
-          "Show this help message.") { $stdout.puts opts; exit }
-
-    opts.separator ""
-    opts.separator "Examples: "
-
-    opts.separator "    rails runner 'puts Rails.env'"
-    opts.separator "        This runs the code `puts Rails.env` after loading the app"
-    opts.separator ""
-    opts.separator "    rails runner path/to/filename.rb"
-    opts.separator "        This runs the Ruby file located at `path/to/filename.rb` after loading the app"
-
-  if RbConfig::CONFIG['host_os'] !~ /mswin|mingw/
-    opts.separator ""
-    opts.separator "You can also use runner as a shebang line for your executables:"
-    opts.separator "    -------------------------------------------------------------"
-    opts.separator "    #!/usr/bin/env #{File.expand_path(command)}"
-    opts.separator ""
-    opts.separator "    Product.all.each { |p| p.price *= 2 ; p.save! }"
-    opts.separator "    -------------------------------------------------------------"
-  end
-
-  opts.order! { |o| code_or_file ||= o } rescue retry
-end
-
-ARGV.delete(code_or_file)
-
-ENV["RAILS_ENV"] = options[:environment]
-
-require APP_PATH
-Rails.application.require_environment!
-Rails.application.load_runner
-
-if code_or_file.nil?
-  $stderr.puts "Run '#{command} -h' for help."
-  exit 1
-elsif File.exist?(code_or_file)
-  $0 = code_or_file
-  Kernel.load code_or_file
-else
-  begin
-    eval(code_or_file, binding, __FILE__, __LINE__)
-  rescue SyntaxError, NameError
-    $stderr.puts "Please specify a valid ruby command or the path of a script to run."
-    $stderr.puts "Run '#{command} -h' for help."
-    exit 1
-  end
-end
diff --git a/railties/lib/rails/commands/runner/USAGE b/railties/lib/rails/commands/runner/USAGE
new file mode 100644
index 0000000000..24b60037f0
--- /dev/null
+++ b/railties/lib/rails/commands/runner/USAGE
@@ -0,0 +1,20 @@
+Examples:
+
+Run `puts Rails.env` after loading the app:
+
+  <%= executable %> 'puts Rails.env'
+
+Run the Ruby file located at `path/to/filename.rb` after loading the app:
+
+  <%= executable %> path/to/filename.rb
+
+Run the Ruby script read from stdin after loading the app:
+  <%= executable %> -
+
+<% unless Gem.win_platform? %>
+You can also use the runner command as a shebang line for your executables:
+
+  #!/usr/bin/env <%= File.expand_path(executable) %>
+
+  Product.all.each { |p| p.price *= 2 ; p.save! }
+<% end %>
diff --git a/railties/lib/rails/commands/runner/runner_command.rb b/railties/lib/rails/commands/runner/runner_command.rb
new file mode 100644
index 0000000000..30fbf04982
--- /dev/null
+++ b/railties/lib/rails/commands/runner/runner_command.rb
@@ -0,0 +1,53 @@
+# frozen_string_literal: true
+
+module Rails
+  module Command
+    class RunnerCommand < Base # :nodoc:
+      class_option :environment, aliases: "-e", type: :string,
+        default: Rails::Command.environment.dup,
+        desc: "The environment for the runner to operate under (test/development/production)"
+
+      no_commands do
+        def help
+          super
+          puts self.class.desc
+        end
+      end
+
+      def self.banner(*)
+        "#{super} [<'Some.ruby(code)'> | <filename.rb> | -]"
+      end
+
+      def perform(code_or_file = nil, *command_argv)
+        unless code_or_file
+          help
+          exit 1
+        end
+
+        ENV["RAILS_ENV"] = options[:environment]
+
+        require_application_and_environment!
+        Rails.application.load_runner
+
+        ARGV.replace(command_argv)
+
+        if code_or_file == "-"
+          eval($stdin.read, TOPLEVEL_BINDING, "stdin")
+        elsif File.exist?(code_or_file)
+          $0 = code_or_file
+          Kernel.load code_or_file
+        else
+          begin
+            eval(code_or_file, TOPLEVEL_BINDING, __FILE__, __LINE__)
+          rescue SyntaxError, NameError => error
+            $stderr.puts "Please specify a valid ruby command or the path of a script to run."
+            $stderr.puts "Run '#{self.class.executable} -h' for help."
+            $stderr.puts
+            $stderr.puts error
+            exit 1
+          end
+        end
+      end
+    end
+  end
+end
diff --git a/railties/lib/rails/commands/secrets/USAGE b/railties/lib/rails/commands/secrets/USAGE
new file mode 100644
index 0000000000..96e322fe91
--- /dev/null
+++ b/railties/lib/rails/commands/secrets/USAGE
@@ -0,0 +1,60 @@
+=== Storing Encrypted Secrets in Source Control
+
+The Rails `secrets` commands helps encrypting secrets to slim a production
+environment's `ENV` hash. It's also useful for atomic deploys: no need to
+coordinate key changes to get everything working as the keys are shipped
+with the code.
+
+=== Setup
+
+Run `bin/rails secrets:setup` to opt in and generate the `config/secrets.yml.key`
+and `config/secrets.yml.enc` files.
+
+The latter contains all the keys to be encrypted while the former holds the
+encryption key.
+
+Don't lose the key! Put it in a password manager your team can access.
+Should you lose it no one, including you, will be able to access any encrypted
+secrets.
+Don't commit the key! Add `config/secrets.yml.key` to your source control's
+ignore file. If you use Git, Rails handles this for you.
+
+Rails also looks for the key in `ENV["RAILS_MASTER_KEY"]` if that's easier to
+manage.
+
+You could prepend that to your server's start command like this:
+
+   RAILS_MASTER_KEY="im-the-master-now-hahaha" server.start
+
+
+The `config/secrets.yml.enc` has much the same format as `config/secrets.yml`:
+
+   production:
+     secret_key_base: so-secret-very-hidden-wow
+     payment_processing_gateway_key: much-safe-very-gaedwey-wow
+
+But that's where the similarities between `secrets.yml` and `secrets.yml.enc`
+end, e.g. no keys from `secrets.yml` will be moved to `secrets.yml.enc` and
+be encrypted.
+
+A `shared:` top level key is also supported such that any keys there is merged
+into the other environments.
+
+Additionally, Rails won't read encrypted secrets out of the box even if you have
+the key. Add this:
+
+   config.read_encrypted_secrets = true
+
+to the environment you'd like to read encrypted secrets. `bin/rails secrets:setup`
+inserts this into the production environment by default.
+
+=== Editing Secrets
+
+After `bin/rails secrets:setup`, run `bin/rails secrets:edit`.
+
+That command opens a temporary file in `$EDITOR` with the decrypted contents of
+`config/secrets.yml.enc` to edit the encrypted secrets.
+
+When the temporary file is next saved the contents are encrypted and written to
+`config/secrets.yml.enc` while the file itself is destroyed to prevent secrets
+from leaking.
diff --git a/railties/lib/rails/commands/secrets/secrets_command.rb b/railties/lib/rails/commands/secrets/secrets_command.rb
new file mode 100644
index 0000000000..a36ccf314c
--- /dev/null
+++ b/railties/lib/rails/commands/secrets/secrets_command.rb
@@ -0,0 +1,65 @@
+# frozen_string_literal: true
+
+require "active_support"
+require "rails/secrets"
+
+module Rails
+  module Command
+    class SecretsCommand < Rails::Command::Base # :nodoc:
+      no_commands do
+        def help
+          say "Usage:\n  #{self.class.banner}"
+          say ""
+          say self.class.desc
+        end
+      end
+
+      def setup
+        deprecate_in_favor_of_credentials_and_exit
+      end
+
+      def edit
+        if ENV["EDITOR"].to_s.empty?
+          say "No $EDITOR to open decrypted secrets in. Assign one like this:"
+          say ""
+          say %(EDITOR="mate --wait" bin/rails secrets:edit)
+          say ""
+          say "For editors that fork and exit immediately, it's important to pass a wait flag,"
+          say "otherwise the secrets will be saved immediately with no chance to edit."
+
+          return
+        end
+
+        require_application_and_environment!
+
+        Rails::Secrets.read_for_editing do |tmp_path|
+          system("#{ENV["EDITOR"]} #{tmp_path}")
+        end
+
+        say "New secrets encrypted and saved."
+      rescue Interrupt
+        say "Aborted changing encrypted secrets: nothing saved."
+      rescue Rails::Secrets::MissingKeyError => error
+        say error.message
+      rescue Errno::ENOENT => error
+        if error.message =~ /secrets\.yml\.enc/
+          deprecate_in_favor_of_credentials_and_exit
+        else
+          raise
+        end
+      end
+
+      def show
+        say Rails::Secrets.read
+      end
+
+      private
+        def deprecate_in_favor_of_credentials_and_exit
+          say "Encrypted secrets is deprecated in favor of credentials. Run:"
+          say "bin/rails credentials:help"
+
+          exit 1
+        end
+    end
+  end
+end
diff --git a/railties/lib/rails/commands/server.rb b/railties/lib/rails/commands/server.rb
deleted file mode 100644
index 7418dff18b..0000000000
--- a/railties/lib/rails/commands/server.rb
+++ /dev/null
@@ -1,139 +0,0 @@
-require 'fileutils'
-require 'optparse'
-require 'action_dispatch'
-require 'rails'
-require 'rails/dev_caching'
-
-module Rails
-  class Server < ::Rack::Server
-    class Options
-      DEFAULT_PID_PATH = File.expand_path("tmp/pids/server.pid").freeze
-
-      def parse!(args)
-        args, options = args.dup, {}
-
-        option_parser(options).parse! args
-
-        options[:log_stdout] = options[:daemonize].blank? && (options[:environment] || Rails.env) == "development"
-        options[:server]     = args.shift
-        options
-      end
-
-      private
-
-      def option_parser(options)
-        OptionParser.new do |opts|
-          opts.banner = "Usage: rails server [mongrel, thin etc] [options]"
-          opts.on("-p", "--port=port", Integer,
-                  "Runs Rails on the specified port.", "Default: 3000") { |v| options[:Port] = v }
-          opts.on("-b", "--binding=IP", String,
-                  "Binds Rails to the specified IP.", "Default: localhost") { |v| options[:Host] = v }
-          opts.on("-c", "--config=file", String,
-                  "Uses a custom rackup configuration.") { |v| options[:config] = v }
-          opts.on("-d", "--daemon", "Runs server as a Daemon.") { options[:daemonize] = true }
-          opts.on("-e", "--environment=name", String,
-                  "Specifies the environment to run this server under (test/development/production).",
-                  "Default: development") { |v| options[:environment] = v }
-          opts.on("-P", "--pid=pid", String,
-                  "Specifies the PID file.",
-                  "Default: tmp/pids/server.pid") { |v| options[:pid] = v }
-          opts.on("-C", "--[no-]dev-caching",
-                  "Specifies whether to perform caching in development.",
-                  "true or false") { |v| options[:caching] = v }
-
-          opts.separator ""
-
-          opts.on("-h", "--help", "Shows this help message.") { puts opts; exit }
-        end
-      end
-    end
-
-    def initialize(*)
-      super
-      set_environment
-    end
-
-    # TODO: this is no longer required but we keep it for the moment to support older config.ru files.
-    def app
-      @app ||= begin
-        app = super
-        app.respond_to?(:to_app) ? app.to_app : app
-      end
-    end
-
-    def opt_parser
-      Options.new
-    end
-
-    def set_environment
-      ENV["RAILS_ENV"] ||= options[:environment]
-    end
-
-    def start
-      print_boot_information
-      trap(:INT) { exit }
-      create_tmp_directories
-      setup_dev_caching
-      log_to_stdout if options[:log_stdout]
-
-      super
-    ensure
-      # The '-h' option calls exit before @options is set.
-      # If we call 'options' with it unset, we get double help banners.
-      puts 'Exiting' unless @options && options[:daemonize]
-    end
-
-    def middleware
-      Hash.new([])
-    end
-
-    def default_options
-      super.merge({
-        Port:               ENV.fetch('PORT', 3000).to_i,
-        DoNotReverseLookup: true,
-        environment:        (ENV['RAILS_ENV'] || ENV['RACK_ENV'] || "development").dup,
-        daemonize:          false,
-        caching:            nil,
-        pid:                Options::DEFAULT_PID_PATH,
-        restart_cmd:        restart_command
-      })
-    end
-
-    private
-
-      def setup_dev_caching
-        if options[:environment] == "development"
-          Rails::DevCaching.enable_by_argument(options[:caching])
-        end
-      end
-
-      def print_boot_information
-        url = "#{options[:SSLEnable] ? 'https' : 'http'}://#{options[:Host]}:#{options[:Port]}"
-        puts "=> Booting #{ActiveSupport::Inflector.demodulize(server)}"
-        puts "=> Rails #{Rails.version} application starting in #{Rails.env} on #{url}"
-        puts "=> Run `rails server -h` for more startup options"
-      end
-
-      def create_tmp_directories
-        %w(cache pids sockets).each do |dir_to_make|
-          FileUtils.mkdir_p(File.join(Rails.root, 'tmp', dir_to_make))
-        end
-      end
-
-      def log_to_stdout
-        wrapped_app # touch the app so the logger is set up
-
-        console = ActiveSupport::Logger.new(STDOUT)
-        console.formatter = Rails.logger.formatter
-        console.level = Rails.logger.level
-
-        unless ActiveSupport::Logger.logger_outputs_to?(Rails.logger, STDOUT)
-          Rails.logger.extend(ActiveSupport::Logger.broadcast(console))
-        end
-      end
-
-      def restart_command
-        "bin/rails server #{ARGV.join(' ')}"
-      end
-  end
-end
diff --git a/railties/lib/rails/commands/server/server_command.rb b/railties/lib/rails/commands/server/server_command.rb
new file mode 100644
index 0000000000..703ec59087
--- /dev/null
+++ b/railties/lib/rails/commands/server/server_command.rb
@@ -0,0 +1,249 @@
+# frozen_string_literal: true
+
+require "fileutils"
+require "optparse"
+require "action_dispatch"
+require "rails"
+require "active_support/deprecation"
+require "active_support/core_ext/string/filters"
+require "rails/dev_caching"
+
+module Rails
+  class Server < ::Rack::Server
+    class Options
+      def parse!(args)
+        Rails::Command::ServerCommand.new([], args).server_options
+      end
+    end
+
+    def initialize(options = nil)
+      @default_options = options || {}
+      super(@default_options)
+      set_environment
+    end
+
+    def app
+      @app ||= begin
+        app = super
+        if app.is_a?(Class)
+          ActiveSupport::Deprecation.warn(<<-MSG.squish)
+            Use `Rails::Application` subclass to start the server is deprecated and will be removed in Rails 6.0.
+            Please change `run #{app}` to `run Rails.application` in config.ru.
+          MSG
+        end
+        app.respond_to?(:to_app) ? app.to_app : app
+      end
+    end
+
+    def opt_parser
+      Options.new
+    end
+
+    def set_environment
+      ENV["RAILS_ENV"] ||= options[:environment]
+    end
+
+    def start
+      print_boot_information
+      trap(:INT) { exit }
+      create_tmp_directories
+      setup_dev_caching
+      log_to_stdout if options[:log_stdout]
+
+      super
+    ensure
+      # The '-h' option calls exit before @options is set.
+      # If we call 'options' with it unset, we get double help banners.
+      puts "Exiting" unless @options && options[:daemonize]
+    end
+
+    def middleware
+      Hash.new([])
+    end
+
+    def default_options
+      super.merge(@default_options)
+    end
+
+    private
+      def setup_dev_caching
+        if options[:environment] == "development"
+          Rails::DevCaching.enable_by_argument(options[:caching])
+        end
+      end
+
+      def print_boot_information
+        url = "on #{options[:SSLEnable] ? 'https' : 'http'}://#{options[:Host]}:#{options[:Port]}" unless use_puma?
+        puts "=> Booting #{ActiveSupport::Inflector.demodulize(server)}"
+        puts "=> Rails #{Rails.version} application starting in #{Rails.env} #{url}"
+        puts "=> Run `rails server -h` for more startup options"
+      end
+
+      def create_tmp_directories
+        %w(cache pids sockets).each do |dir_to_make|
+          FileUtils.mkdir_p(File.join(Rails.root, "tmp", dir_to_make))
+        end
+      end
+
+      def log_to_stdout
+        wrapped_app # touch the app so the logger is set up
+
+        console = ActiveSupport::Logger.new(STDOUT)
+        console.formatter = Rails.logger.formatter
+        console.level = Rails.logger.level
+
+        unless ActiveSupport::Logger.logger_outputs_to?(Rails.logger, STDOUT)
+          Rails.logger.extend(ActiveSupport::Logger.broadcast(console))
+        end
+      end
+
+      def restart_command
+        "bin/rails server #{ARGV.join(' ')}"
+      end
+
+      def use_puma?
+        server.to_s == "Rack::Handler::Puma"
+      end
+  end
+
+  module Command
+    class ServerCommand < Base # :nodoc:
+      DEFAULT_PORT = 3000
+      DEFAULT_PID_PATH = "tmp/pids/server.pid".freeze
+
+      class_option :port, aliases: "-p", type: :numeric,
+        desc: "Runs Rails on the specified port - defaults to 3000.", banner: :port
+      class_option :binding, aliases: "-b", type: :string,
+        desc: "Binds Rails to the specified IP - defaults to 'localhost' in development and '0.0.0.0' in other environments'.",
+        banner: :IP
+      class_option :config, aliases: "-c", type: :string, default: "config.ru",
+        desc: "Uses a custom rackup configuration.", banner: :file
+      class_option :daemon, aliases: "-d", type: :boolean, default: false,
+        desc: "Runs server as a Daemon."
+      class_option :environment, aliases: "-e", type: :string,
+        desc: "Specifies the environment to run this server under (development/test/production).", banner: :name
+      class_option :pid, aliases: "-P", type: :string, default: DEFAULT_PID_PATH,
+        desc: "Specifies the PID file."
+      class_option "dev-caching", aliases: "-C", type: :boolean, default: nil,
+        desc: "Specifies whether to perform caching in development."
+      class_option "restart", type: :boolean, default: nil, hide: true
+      class_option "early_hints", type: :boolean, default: nil, desc: "Enables HTTP/2 early hints."
+
+      def initialize(args = [], local_options = {}, config = {})
+        @original_options = local_options
+        super
+        @server = self.args.shift
+        @log_stdout = options[:daemon].blank? && (options[:environment] || Rails.env) == "development"
+      end
+
+      def perform
+        set_application_directory!
+        prepare_restart
+        Rails::Server.new(server_options).tap do |server|
+          # Require application after server sets environment to propagate
+          # the --environment option.
+          require APP_PATH
+          Dir.chdir(Rails.application.root)
+          server.start
+        end
+      end
+
+      no_commands do
+        def server_options
+          {
+            user_supplied_options: user_supplied_options,
+            server:                @server,
+            log_stdout:            @log_stdout,
+            Port:                  port,
+            Host:                  host,
+            DoNotReverseLookup:    true,
+            config:                options[:config],
+            environment:           environment,
+            daemonize:             options[:daemon],
+            pid:                   pid,
+            caching:               options["dev-caching"],
+            restart_cmd:           restart_command,
+            early_hints:           early_hints
+          }
+        end
+      end
+
+      private
+        def user_supplied_options
+          @user_supplied_options ||= begin
+            # Convert incoming options array to a hash of flags
+            #   ["-p3001", "-C", "--binding", "127.0.0.1"] # => {"-p"=>true, "-C"=>true, "--binding"=>true}
+            user_flag = {}
+            @original_options.each do |command|
+              if command.to_s.start_with?("--")
+                option = command.split("=")[0]
+                user_flag[option] = true
+              elsif command =~ /\A(-.)/
+                user_flag[Regexp.last_match[0]] = true
+              end
+            end
+
+            # Collect all options that the user has explicitly defined so we can
+            # differentiate them from defaults
+            user_supplied_options = []
+            self.class.class_options.select do |key, option|
+              if option.aliases.any? { |name| user_flag[name] } || user_flag["--#{option.name}"]
+                name = option.name.to_sym
+                case name
+                when :port
+                  name = :Port
+                when :binding
+                  name = :Host
+                when :"dev-caching"
+                  name = :caching
+                when :daemonize
+                  name = :daemon
+                end
+                user_supplied_options << name
+              end
+            end
+            user_supplied_options << :Host if ENV["HOST"]
+            user_supplied_options << :Port if ENV["PORT"]
+            user_supplied_options.uniq
+          end
+        end
+
+        def port
+          options[:port] || ENV.fetch("PORT", DEFAULT_PORT).to_i
+        end
+
+        def host
+          if options[:binding]
+            options[:binding]
+          else
+            default_host = environment == "development" ? "localhost" : "0.0.0.0"
+            ENV.fetch("HOST", default_host)
+          end
+        end
+
+        def environment
+          options[:environment] || Rails::Command.environment
+        end
+
+        def restart_command
+          "bin/rails server #{@server} #{@original_options.join(" ")} --restart"
+        end
+
+        def early_hints
+          options[:early_hints]
+        end
+
+        def pid
+          File.expand_path(options[:pid])
+        end
+
+        def self.banner(*)
+          "rails server [puma, thin etc] [options]"
+        end
+
+        def prepare_restart
+          FileUtils.rm_f(options[:pid]) if options[:restart]
+        end
+    end
+  end
+end
diff --git a/railties/lib/rails/commands/test.rb b/railties/lib/rails/commands/test.rb
deleted file mode 100644
index dd069f081f..0000000000
--- a/railties/lib/rails/commands/test.rb
+++ /dev/null
@@ -1,9 +0,0 @@
-require "rails/test_unit/minitest_plugin"
-
-if defined?(ENGINE_ROOT)
-  $: << File.expand_path('test', ENGINE_ROOT)
-else
-  $: << File.expand_path('../../test', APP_PATH)
-end
-
-exit Minitest.run(ARGV)
diff --git a/railties/lib/rails/commands/test/test_command.rb b/railties/lib/rails/commands/test/test_command.rb
new file mode 100644
index 0000000000..00ea9ac4a6
--- /dev/null
+++ b/railties/lib/rails/commands/test/test_command.rb
@@ -0,0 +1,37 @@
+# frozen_string_literal: true
+
+require "rails/command"
+require "rails/test_unit/runner"
+require "rails/test_unit/reporter"
+
+module Rails
+  module Command
+    class TestCommand < Base # :nodoc:
+      no_commands do
+        def help
+          say "Usage: #{Rails::TestUnitReporter.executable} [options] [files or directories]"
+          say ""
+          say "You can run a single test by appending a line number to a filename:"
+          say ""
+          say "    #{Rails::TestUnitReporter.executable} test/models/user_test.rb:27"
+          say ""
+          say "You can run multiple files and directories at the same time:"
+          say ""
+          say "    #{Rails::TestUnitReporter.executable} test/controllers test/integration/login_test.rb"
+          say ""
+          say "By default test failures and errors are reported inline during a run."
+          say ""
+
+          Minitest.run(%w(--help))
+        end
+      end
+
+      def perform(*)
+        $LOAD_PATH << Rails::Command.root.join("test").to_s
+
+        Rails::TestUnit::Runner.parse_options(ARGV)
+        Rails::TestUnit::Runner.run(ARGV)
+      end
+    end
+  end
+end
diff --git a/railties/lib/rails/commands/version/version_command.rb b/railties/lib/rails/commands/version/version_command.rb
new file mode 100644
index 0000000000..3e2112b6d4
--- /dev/null
+++ b/railties/lib/rails/commands/version/version_command.rb
@@ -0,0 +1,11 @@
+# frozen_string_literal: true
+
+module Rails
+  module Command
+    class VersionCommand < Base # :nodoc:
+      def perform
+        Rails::Command.invoke :application, [ "--version" ]
+      end
+    end
+  end
+end
diff --git a/railties/lib/rails/configuration.rb b/railties/lib/rails/configuration.rb
index 30eafd59f2..d3a54d9364 100644
--- a/railties/lib/rails/configuration.rb
+++ b/railties/lib/rails/configuration.rb
@@ -1,7 +1,9 @@
-require 'active_support/ordered_options'
-require 'active_support/core_ext/object'
-require 'rails/paths'
-require 'rails/rack'
+# frozen_string_literal: true
+
+require "active_support/ordered_options"
+require "active_support/core_ext/object"
+require "rails/paths"
+require "rails/rack"
 
 module Rails
   module Configuration
@@ -91,8 +93,8 @@ module Rails
       attr_reader :hidden_namespaces
 
       def initialize
-        @aliases = Hash.new { |h,k| h[k] = {} }
-        @options = Hash.new { |h,k| h[k] = {} }
+        @aliases = Hash.new { |h, k| h[k] = {} }
+        @options = Hash.new { |h, k| h[k] = {} }
         @fallbacks = {}
         @templates = []
         @colorize_logging = true
@@ -112,7 +114,7 @@ module Rails
       end
 
       def method_missing(method, *args)
-        method = method.to_s.sub(/=$/, '').to_sym
+        method = method.to_s.sub(/=$/, "").to_sym
 
         return @options[method] if args.empty?
 
diff --git a/railties/lib/rails/console/app.rb b/railties/lib/rails/console/app.rb
index 9ad77e0a80..c37583ce9a 100644
--- a/railties/lib/rails/console/app.rb
+++ b/railties/lib/rails/console/app.rb
@@ -1,11 +1,13 @@
-require 'active_support/all'
-require 'action_controller'
+# frozen_string_literal: true
+
+require "active_support/all"
+require "action_controller"
 
 module Rails
   module ConsoleMethods
     # reference the global "app" instance, created on demand. To recreate the
     # instance, pass a non-false value as the parameter.
-    def app(create=false)
+    def app(create = false)
       @app_integration_instance = nil if create
       @app_integration_instance ||= new_session do |sess|
         sess.host! "www.example.com"
@@ -27,7 +29,7 @@ module Rails
     end
 
     # reloads the environment
-    def reload!(print=true)
+    def reload!(print = true)
       puts "Reloading..." if print
       Rails.application.reloader.reload!
       true
diff --git a/railties/lib/rails/console/helpers.rb b/railties/lib/rails/console/helpers.rb
index a33f71dc5b..39fbc55606 100644
--- a/railties/lib/rails/console/helpers.rb
+++ b/railties/lib/rails/console/helpers.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module Rails
   module ConsoleMethods
     # Gets the helper methods available to the controller.
diff --git a/railties/lib/rails/dev_caching.rb b/railties/lib/rails/dev_caching.rb
index f2a53d6417..ff629b2527 100644
--- a/railties/lib/rails/dev_caching.rb
+++ b/railties/lib/rails/dev_caching.rb
@@ -1,27 +1,28 @@
-require 'fileutils'
+# frozen_string_literal: true
+
+require "fileutils"
 
 module Rails
   module DevCaching # :nodoc:
     class << self
-      FILE = 'tmp/caching-dev.txt'
+      FILE = "tmp/caching-dev.txt"
 
       def enable_by_file
-        FileUtils.mkdir_p('tmp')
+        FileUtils.mkdir_p("tmp")
 
         if File.exist?(FILE)
           delete_cache_file
-          puts 'Development mode is no longer being cached.'
+          puts "Development mode is no longer being cached."
         else
           create_cache_file
-          puts 'Development mode is now being cached.'
+          puts "Development mode is now being cached."
         end
 
-        FileUtils.touch 'tmp/restart.txt'
-        FileUtils.rm_f('tmp/pids/server.pid')
+        FileUtils.touch "tmp/restart.txt"
       end
 
       def enable_by_argument(caching)
-        FileUtils.mkdir_p('tmp')
+        FileUtils.mkdir_p("tmp")
 
         if caching
           create_cache_file
diff --git a/railties/lib/rails/engine.rb b/railties/lib/rails/engine.rb
index 9701409755..6a13a84108 100644
--- a/railties/lib/rails/engine.rb
+++ b/railties/lib/rails/engine.rb
@@ -1,8 +1,10 @@
-require 'rails/railtie'
-require 'rails/engine/railties'
-require 'active_support/core_ext/module/delegation'
-require 'pathname'
-require 'thread'
+# frozen_string_literal: true
+
+require "rails/railtie"
+require "rails/engine/railties"
+require "active_support/core_ext/module/delegation"
+require "pathname"
+require "thread"
 
 module Rails
   # <tt>Rails::Engine</tt> allows you to wrap a specific Rails application or subset of
@@ -40,7 +42,7 @@ module Rails
   #
   #   class MyEngine < Rails::Engine
   #     # Add a load path for this specific Engine
-  #     config.autoload_paths << File.expand_path("../lib/some/path", __FILE__)
+  #     config.autoload_paths << File.expand_path("lib/some/path", __dir__)
   #
   #     initializer "my_engine.add_middleware" do |app|
   #       app.middleware.use MyEngine::Middleware
@@ -109,7 +111,7 @@ module Rails
   #
   # == Endpoint
   #
-  # An engine can also be a rack application. It can be useful if you have a rack application that
+  # An engine can also be a Rack application. It can be useful if you have a Rack application that
   # you would like to wrap with +Engine+ and provide with some of the +Engine+'s features.
   #
   # To do that, use the +endpoint+ method:
@@ -128,7 +130,7 @@ module Rails
   #
   # == Middleware stack
   #
-  # As an engine can now be a rack endpoint, it can also have a middleware
+  # As an engine can now be a Rack endpoint, it can also have a middleware
   # stack. The usage is exactly the same as in <tt>Application</tt>:
   #
   #   module MyEngine
@@ -337,7 +339,7 @@ module Rails
   # == Loading priority
   #
   # In order to change engine's priority you can use +config.railties_order+ in the main application.
-  # It will affect the priority of loading views, helpers, assets and all the other files
+  # It will affect the priority of loading views, helpers, assets, and all the other files
   # related to engine or application.
   #
   #   # load Blog::Engine with highest priority, followed by application and other railties
@@ -380,7 +382,7 @@ module Rails
       def isolate_namespace(mod)
         engine_name(generate_railtie_name(mod.name))
 
-        self.routes.default_scope = { module: ActiveSupport::Inflector.underscore(mod.name) }
+        routes.default_scope = { module: ActiveSupport::Inflector.underscore(mod.name) }
         self.isolated = true
 
         unless mod.respond_to?(:railtie_namespace)
@@ -402,7 +404,7 @@ module Rails
             end
 
             unless mod.respond_to?(:railtie_routes_url_helpers)
-              define_method(:railtie_routes_url_helpers) {|include_path_helpers = true| railtie.routes.url_helpers(include_path_helpers) }
+              define_method(:railtie_routes_url_helpers) { |include_path_helpers = true| railtie.routes.url_helpers(include_path_helpers) }
             end
           end
         end
@@ -436,7 +438,7 @@ module Rails
 
     # Load console and invoke the registered hooks.
     # Check <tt>Rails::Railtie.console</tt> for more info.
-    def load_console(app=self)
+    def load_console(app = self)
       require "rails/console/app"
       require "rails/console/helpers"
       run_console_blocks(app)
@@ -445,14 +447,14 @@ module Rails
 
     # Load Rails runner and invoke the registered hooks.
     # Check <tt>Rails::Railtie.runner</tt> for more info.
-    def load_runner(app=self)
+    def load_runner(app = self)
       run_runner_blocks(app)
       self
     end
 
     # Load Rake, railties tasks and invoke the registered hooks.
     # Check <tt>Rails::Railtie.rake_tasks</tt> for more info.
-    def load_tasks(app=self)
+    def load_tasks(app = self)
       require "rake"
       run_tasks_blocks(app)
       self
@@ -460,7 +462,7 @@ module Rails
 
     # Load Rails generators and invoke the registered hooks.
     # Check <tt>Rails::Railtie.generators</tt> for more info.
-    def load_generators(app=self)
+    def load_generators(app = self)
       require "rails/generators"
       run_generators_blocks(app)
       Rails::Generators.configure!(app.config.generators)
@@ -499,7 +501,7 @@ module Rails
       paths["app/helpers"].existent
     end
 
-    # Returns the underlying rack application for this engine.
+    # Returns the underlying Rack application for this engine.
     def app
       @app || @app_build_lock.synchronize {
         @app ||= begin
@@ -549,7 +551,7 @@ module Rails
       load(seed_file) if seed_file
     end
 
-    # Add configured load paths to ruby load paths and remove duplicates.
+    # Add configured load paths to Ruby's load path, and remove duplicate entries.
     initializer :set_load_path, before: :bootstrap_hook do
       _all_load_paths.reverse_each do |path|
         $LOAD_PATH.unshift(path) if File.directory?(path)
@@ -573,7 +575,7 @@ module Rails
     end
 
     initializer :add_routing_paths do |app|
-      routing_paths = self.paths["config/routes.rb"].existent
+      routing_paths = paths["config/routes.rb"].existent
 
       if routes? || routing_paths.any?
         app.routes_reloader.paths.unshift(*routing_paths)
@@ -590,8 +592,8 @@ module Rails
     initializer :add_view_paths do
       views = paths["app/views"].existent
       unless views.empty?
-        ActiveSupport.on_load(:action_controller){ prepend_view_path(views) if respond_to?(:prepend_view_path) }
-        ActiveSupport.on_load(:action_mailer){ prepend_view_path(views) }
+        ActiveSupport.on_load(:action_controller) { prepend_view_path(views) if respond_to?(:prepend_view_path) }
+        ActiveSupport.on_load(:action_mailer) { prepend_view_path(views) }
       end
     end
 
@@ -619,7 +621,7 @@ module Rails
     end
 
     rake_tasks do
-      next if self.is_a?(Rails::Application)
+      next if is_a?(Rails::Application)
       next unless has_migrations?
 
       namespace railtie_name do
@@ -643,62 +645,61 @@ module Rails
 
     protected
 
-    def load_config_initializer(initializer)
-      ActiveSupport::Notifications.instrument('load_config_initializer.railties', initializer: initializer) do
-        load(initializer)
+      def run_tasks_blocks(*) #:nodoc:
+        super
+        paths["lib/tasks"].existent.sort.each { |ext| load(ext) }
       end
-    end
 
-    def run_tasks_blocks(*) #:nodoc:
-      super
-      paths["lib/tasks"].existent.sort.each { |ext| load(ext) }
-    end
-
-    def has_migrations? #:nodoc:
-      paths["db/migrate"].existent.any?
-    end
+    private
 
-    def self.find_root_with_flag(flag, root_path, default=nil) #:nodoc:
+      def load_config_initializer(initializer) # :doc:
+        ActiveSupport::Notifications.instrument("load_config_initializer.railties", initializer: initializer) do
+          load(initializer)
+        end
+      end
 
-      while root_path && File.directory?(root_path) && !File.exist?("#{root_path}/#{flag}")
-        parent = File.dirname(root_path)
-        root_path = parent != root_path && parent
+      def has_migrations?
+        paths["db/migrate"].existent.any?
       end
 
-      root = File.exist?("#{root_path}/#{flag}") ? root_path : default
-      raise "Could not find root path for #{self}" unless root
+      def self.find_root_with_flag(flag, root_path, default = nil) #:nodoc:
+        while root_path && File.directory?(root_path) && !File.exist?("#{root_path}/#{flag}")
+          parent = File.dirname(root_path)
+          root_path = parent != root_path && parent
+        end
 
-      Pathname.new File.realpath root
-    end
+        root = File.exist?("#{root_path}/#{flag}") ? root_path : default
+        raise "Could not find root path for #{self}" unless root
 
-    def default_middleware_stack #:nodoc:
-      ActionDispatch::MiddlewareStack.new
-    end
+        Pathname.new File.realpath root
+      end
 
-    def _all_autoload_once_paths #:nodoc:
-      config.autoload_once_paths
-    end
+      def default_middleware_stack
+        ActionDispatch::MiddlewareStack.new
+      end
 
-    def _all_autoload_paths #:nodoc:
-      @_all_autoload_paths ||= (config.autoload_paths + config.eager_load_paths + config.autoload_once_paths).uniq
-    end
+      def _all_autoload_once_paths
+        config.autoload_once_paths
+      end
 
-    def _all_load_paths #:nodoc:
-      @_all_load_paths ||= (config.paths.load_paths + _all_autoload_paths).uniq
-    end
+      def _all_autoload_paths
+        @_all_autoload_paths ||= (config.autoload_paths + config.eager_load_paths + config.autoload_once_paths).uniq
+      end
 
-    private
+      def _all_load_paths
+        @_all_load_paths ||= (config.paths.load_paths + _all_autoload_paths).uniq
+      end
 
-    def build_request(env)
-      env.merge!(env_config)
-      req = ActionDispatch::Request.new env
-      req.routes = routes
-      req.engine_script_name = req.script_name
-      req
-    end
+      def build_request(env)
+        env.merge!(env_config)
+        req = ActionDispatch::Request.new env
+        req.routes = routes
+        req.engine_script_name = req.script_name
+        req
+      end
 
-    def build_middleware
-      config.middleware
-    end
+      def build_middleware
+        config.middleware
+      end
   end
 end
diff --git a/railties/lib/rails/engine/commands.rb b/railties/lib/rails/engine/commands.rb
index 7bbd9ef744..05218640c6 100644
--- a/railties/lib/rails/engine/commands.rb
+++ b/railties/lib/rails/engine/commands.rb
@@ -1,14 +1,9 @@
-require 'rails/engine/commands_tasks'
+# frozen_string_literal: true
 
-ARGV << '--help' if ARGV.empty?
+unless defined?(APP_PATH)
+  if File.exist?(File.expand_path("test/dummy/config/application.rb", ENGINE_ROOT))
+    APP_PATH = File.expand_path("test/dummy/config/application", ENGINE_ROOT)
+  end
+end
 
-aliases = {
-  "g" => "generate",
-  "d" => "destroy",
-  "t" => "test"
-}
-
-command = ARGV.shift
-command = aliases[command] || command
-
-Rails::Engine::CommandsTasks.new(ARGV).run_command!(command)
+require "rails/commands"
diff --git a/railties/lib/rails/engine/commands_tasks.rb b/railties/lib/rails/engine/commands_tasks.rb
deleted file mode 100644
index fa3ee59b7d..0000000000
--- a/railties/lib/rails/engine/commands_tasks.rb
+++ /dev/null
@@ -1,116 +0,0 @@
-require 'rails/commands/rake_proxy'
-
-module Rails
-  class Engine
-    class CommandsTasks # :nodoc:
-      include Rails::RakeProxy
-
-      attr_reader :argv
-
-      HELP_MESSAGE = <<-EOT
-Usage: rails COMMAND [ARGS]
-
-The common Rails commands available for engines are:
- generate    Generate new code (short-cut alias: "g")
- destroy     Undo code generated with "generate" (short-cut alias: "d")
- test        Run tests (short-cut alias: "t")
-
-All commands can be run with -h for more information.
-
-If you want to run any commands that need to be run in context
-of the application, like `rails server` or `rails console`,
-you should do it from application's directory (typically test/dummy).
-
-In addition to those commands, there are:
-  EOT
-
-      COMMAND_WHITELIST = %w(generate destroy version help test)
-
-      def initialize(argv)
-        @argv = argv
-      end
-
-      def run_command!(command)
-        command = parse_command(command)
-
-        if COMMAND_WHITELIST.include?(command)
-          send(command)
-        else
-          run_rake_task(command)
-        end
-      end
-
-      def generate
-        generate_or_destroy(:generate)
-      end
-
-      def destroy
-        generate_or_destroy(:destroy)
-      end
-
-      def test
-        require_command!("test")
-      end
-
-      def version
-        argv.unshift '--version'
-        require_command!("application")
-      end
-
-      def help
-        write_help_message
-        write_commands(formatted_rake_tasks)
-      end
-
-      private
-
-        def require_command!(command)
-          require "rails/commands/#{command}"
-        end
-
-        def generate_or_destroy(command)
-          load_generators
-          require_command!(command)
-        end
-
-        def load_generators
-          require 'rails/generators'
-          require ENGINE_PATH
-
-          engine = ::Rails::Engine.find(ENGINE_ROOT)
-          Rails::Generators.namespace = engine.railtie_namespace
-          engine.load_generators
-        end
-
-        def write_help_message
-          puts HELP_MESSAGE
-        end
-
-        def write_commands(commands)
-          width = commands.map { |name, _| name.size }.max || 10
-          commands.each { |command| printf(" %-#{width}s   %s\n", *command) }
-        end
-
-        def parse_command(command)
-          case command
-          when '--version', '-v'
-            'version'
-          when '--help', '-h'
-            'help'
-          else
-            command
-          end
-        end
-
-        def rake_tasks
-          return @rake_tasks if defined?(@rake_tasks)
-
-          load_generators
-          Rake::TaskManager.record_task_metadata = true
-          Rake.application.init('rails')
-          Rake.application.load_rakefile
-          @rake_tasks = Rake.application.tasks.select(&:comment)
-        end
-    end
-  end
-end
diff --git a/railties/lib/rails/engine/configuration.rb b/railties/lib/rails/engine/configuration.rb
index 294d07446f..6bf0406b21 100644
--- a/railties/lib/rails/engine/configuration.rb
+++ b/railties/lib/rails/engine/configuration.rb
@@ -1,4 +1,6 @@
-require 'rails/railtie/configuration'
+# frozen_string_literal: true
+
+require "rails/railtie/configuration"
 
 module Rails
   class Engine
@@ -7,7 +9,7 @@ module Rails
       attr_accessor :middleware
       attr_writer :eager_load_paths, :autoload_once_paths, :autoload_paths
 
-      def initialize(root=nil)
+      def initialize(root = nil)
         super()
         @root = root
         @generators = app_generators.dup
diff --git a/railties/lib/rails/engine/railties.rb b/railties/lib/rails/engine/railties.rb
index 9969a1475d..052b74c880 100644
--- a/railties/lib/rails/engine/railties.rb
+++ b/railties/lib/rails/engine/railties.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module Rails
   class Engine < Railtie
     class Railties
diff --git a/railties/lib/rails/engine/updater.rb b/railties/lib/rails/engine/updater.rb
new file mode 100644
index 0000000000..be7a47124a
--- /dev/null
+++ b/railties/lib/rails/engine/updater.rb
@@ -0,0 +1,21 @@
+# frozen_string_literal: true
+
+require "rails/generators"
+require "rails/generators/rails/plugin/plugin_generator"
+
+module Rails
+  class Engine
+    class Updater
+      class << self
+        def generator
+          @generator ||= Rails::Generators::PluginGenerator.new ["plugin"],
+            { engine: true }, { destination_root: ENGINE_ROOT }
+        end
+
+        def run(action)
+          generator.send(action)
+        end
+      end
+    end
+  end
+end
diff --git a/railties/lib/rails/gem_version.rb b/railties/lib/rails/gem_version.rb
index 9c49e0655a..2cc861a1bd 100644
--- a/railties/lib/rails/gem_version.rb
+++ b/railties/lib/rails/gem_version.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module Rails
   # Returns the version of the currently loaded Rails as a <tt>Gem::Version</tt>
   def self.gem_version
@@ -6,9 +8,9 @@ module Rails
 
   module VERSION
     MAJOR = 5
-    MINOR = 1
+    MINOR = 2
     TINY  = 0
-    PRE   = "alpha"
+    PRE   = "beta2"
 
     STRING = [MAJOR, MINOR, TINY, PRE].compact.join(".")
   end
diff --git a/railties/lib/rails/generators.rb b/railties/lib/rails/generators.rb
index 330bd7ec5d..6c9c109f17 100644
--- a/railties/lib/rails/generators.rb
+++ b/railties/lib/rails/generators.rb
@@ -1,45 +1,51 @@
-activesupport_path = File.expand_path('../../../../activesupport/lib', __FILE__)
+# frozen_string_literal: true
+
+activesupport_path = File.expand_path("../../../activesupport/lib", __dir__)
 $:.unshift(activesupport_path) if File.directory?(activesupport_path) && !$:.include?(activesupport_path)
 
-require 'thor/group'
+require "thor/group"
+require "rails/command"
 
-require 'active_support'
-require 'active_support/core_ext/object/blank'
-require 'active_support/core_ext/kernel/singleton_class'
-require 'active_support/core_ext/array/extract_options'
-require 'active_support/core_ext/hash/deep_merge'
-require 'active_support/core_ext/module/attribute_accessors'
-require 'active_support/core_ext/string/inflections'
+require "active_support"
+require "active_support/core_ext/object/blank"
+require "active_support/core_ext/kernel/singleton_class"
+require "active_support/core_ext/array/extract_options"
+require "active_support/core_ext/hash/deep_merge"
+require "active_support/core_ext/module/attribute_accessors"
+require "active_support/core_ext/string/indent"
+require "active_support/core_ext/string/inflections"
 
 module Rails
   module Generators
-    autoload :Actions,         'rails/generators/actions'
-    autoload :ActiveModel,     'rails/generators/active_model'
-    autoload :Base,            'rails/generators/base'
-    autoload :Migration,       'rails/generators/migration'
-    autoload :NamedBase,       'rails/generators/named_base'
-    autoload :ResourceHelpers, 'rails/generators/resource_helpers'
-    autoload :TestCase,        'rails/generators/test_case'
+    include Rails::Command::Behavior
+
+    autoload :Actions,         "rails/generators/actions"
+    autoload :ActiveModel,     "rails/generators/active_model"
+    autoload :Base,            "rails/generators/base"
+    autoload :Migration,       "rails/generators/migration"
+    autoload :NamedBase,       "rails/generators/named_base"
+    autoload :ResourceHelpers, "rails/generators/resource_helpers"
+    autoload :TestCase,        "rails/generators/test_case"
 
     mattr_accessor :namespace
 
     DEFAULT_ALIASES = {
       rails: {
-        actions: '-a',
-        orm: '-o',
-        javascripts: '-j',
-        javascript_engine: '-je',
-        resource_controller: '-c',
-        scaffold_controller: '-c',
-        stylesheets: '-y',
-        stylesheet_engine: '-se',
-        scaffold_stylesheet: '-ss',
-        template_engine: '-e',
-        test_framework: '-t'
+        actions: "-a",
+        orm: "-o",
+        javascripts: "-j",
+        javascript_engine: "-je",
+        resource_controller: "-c",
+        scaffold_controller: "-c",
+        stylesheets: "-y",
+        stylesheet_engine: "-se",
+        scaffold_stylesheet: "-ss",
+        template_engine: "-e",
+        test_framework: "-t"
       },
 
       test_unit: {
-        fixture_replacement: '-r',
+        fixture_replacement: "-r",
       }
     }
 
@@ -59,340 +65,257 @@ module Rails
         stylesheets: true,
         stylesheet_engine: :css,
         scaffold_stylesheet: true,
-        test_framework: false,
+        system_tests: nil,
+        test_framework: nil,
         template_engine: :erb
       }
     }
 
-    def self.configure!(config) #:nodoc:
-      api_only! if config.api_only
-      no_color! unless config.colorize_logging
-      aliases.deep_merge! config.aliases
-      options.deep_merge! config.options
-      fallbacks.merge! config.fallbacks
-      templates_path.concat config.templates
-      templates_path.uniq!
-      hide_namespaces(*config.hidden_namespaces)
-    end
-
-    def self.templates_path #:nodoc:
-      @templates_path ||= []
-    end
-
-    def self.aliases #:nodoc:
-      @aliases ||= DEFAULT_ALIASES.dup
-    end
-
-    def self.options #:nodoc:
-      @options ||= DEFAULT_OPTIONS.dup
-    end
-
-    # Hold configured generators fallbacks. If a plugin developer wants a
-    # generator group to fallback to another group in case of missing generators,
-    # they can add a fallback.
-    #
-    # For example, shoulda is considered a test_framework and is an extension
-    # of test_unit. However, most part of shoulda generators are similar to
-    # test_unit ones.
-    #
-    # Shoulda then can tell generators to search for test_unit generators when
-    # some of them are not available by adding a fallback:
-    #
-    #   Rails::Generators.fallbacks[:shoulda] = :test_unit
-    def self.fallbacks
-      @fallbacks ||= {}
-    end
-
-    # Configure generators for API only applications. It basically hides
-    # everything that is usually browser related, such as assets and session
-    # migration generators, and completely disable helpers and assets
-    # so generators such as scaffold won't create them.
-    def self.api_only!
-      hide_namespaces "assets", "helper", "css", "js"
-
-      options[:rails].merge!(
-        api: true,
-        assets: false,
-        helper: false,
-        template_engine: nil
-      )
-
-      if ARGV.first == 'mailer'
-        options[:rails].merge!(template_engine: :erb)
+    class << self
+      def configure!(config) #:nodoc:
+        api_only! if config.api_only
+        no_color! unless config.colorize_logging
+        aliases.deep_merge! config.aliases
+        options.deep_merge! config.options
+        fallbacks.merge! config.fallbacks
+        templates_path.concat config.templates
+        templates_path.uniq!
+        hide_namespaces(*config.hidden_namespaces)
       end
-    end
-
-    # Remove the color from output.
-    def self.no_color!
-      Thor::Base.shell = Thor::Shell::Basic
-    end
 
-    # Track all generators subclasses.
-    def self.subclasses
-      @subclasses ||= []
-    end
-
-    # Rails finds namespaces similar to thor, it only adds one rule:
-    #
-    # Generators names must end with "_generator.rb". This is required because Rails
-    # looks in load paths and loads the generator just before it's going to be used.
-    #
-    #   find_by_namespace :webrat, :rails, :integration
-    #
-    # Will search for the following generators:
-    #
-    #   "rails:webrat", "webrat:integration", "webrat"
-    #
-    # Notice that "rails:generators:webrat" could be loaded as well, what
-    # Rails looks for is the first and last parts of the namespace.
-    def self.find_by_namespace(name, base=nil, context=nil) #:nodoc:
-      lookups = []
-      lookups << "#{base}:#{name}"    if base
-      lookups << "#{name}:#{context}" if context
-
-      unless base || context
-        unless name.to_s.include?(?:)
-          lookups << "#{name}:#{name}"
-          lookups << "rails:#{name}"
-        end
-        lookups << "#{name}"
+      def templates_path #:nodoc:
+        @templates_path ||= []
       end
 
-      lookup(lookups)
+      def aliases #:nodoc:
+        @aliases ||= DEFAULT_ALIASES.dup
+      end
 
-      namespaces = Hash[subclasses.map { |klass| [klass.namespace, klass] }]
+      def options #:nodoc:
+        @options ||= DEFAULT_OPTIONS.dup
+      end
 
-      lookups.each do |namespace|
-        klass = namespaces[namespace]
-        return klass if klass
+      # Hold configured generators fallbacks. If a plugin developer wants a
+      # generator group to fallback to another group in case of missing generators,
+      # they can add a fallback.
+      #
+      # For example, shoulda is considered a test_framework and is an extension
+      # of test_unit. However, most part of shoulda generators are similar to
+      # test_unit ones.
+      #
+      # Shoulda then can tell generators to search for test_unit generators when
+      # some of them are not available by adding a fallback:
+      #
+      #   Rails::Generators.fallbacks[:shoulda] = :test_unit
+      def fallbacks
+        @fallbacks ||= {}
       end
 
-      invoke_fallbacks_for(name, base) || invoke_fallbacks_for(context, name)
-    end
+      # Configure generators for API only applications. It basically hides
+      # everything that is usually browser related, such as assets and session
+      # migration generators, and completely disable helpers and assets
+      # so generators such as scaffold won't create them.
+      def api_only!
+        hide_namespaces "assets", "helper", "css", "js"
+
+        options[:rails].merge!(
+          api: true,
+          assets: false,
+          helper: false,
+          template_engine: nil
+        )
+
+        if ARGV.first == "mailer"
+          options[:rails].merge!(template_engine: :erb)
+        end
+      end
 
-    # Receives a namespace, arguments and the behavior to invoke the generator.
-    # It's used as the default entry point for generate, destroy and update
-    # commands.
-    def self.invoke(namespace, args=ARGV, config={})
-      names = namespace.to_s.split(':')
-      if klass = find_by_namespace(names.pop, names.any? && names.join(':'))
-        args << "--help" if args.empty? && klass.arguments.any?(&:required?)
-        klass.start(args, config)
-      else
-        options     = sorted_groups.flat_map(&:last)
-        suggestions = options.sort_by {|suggested| levenshtein_distance(namespace.to_s, suggested) }.first(3)
-        msg =  "Could not find generator '#{namespace}'. "
-        msg << "Maybe you meant #{ suggestions.map {|s| "'#{s}'"}.to_sentence(last_word_connector: " or ", locale: :en) }\n"
-        msg << "Run `rails generate --help` for more options."
-        puts msg
+      # Remove the color from output.
+      def no_color!
+        Thor::Base.shell = Thor::Shell::Basic
       end
-    end
 
-    # Returns an array of generator namespaces that are hidden.
-    # Generator namespaces may be hidden for a variety of reasons.
-    # Some are aliased such as "rails:migration" and can be
-    # invoked with the shorter "migration", others are private to other generators
-    # such as "css:scaffold".
-    def self.hidden_namespaces
-      @hidden_namespaces ||= begin
-        orm      = options[:rails][:orm]
-        test     = options[:rails][:test_framework]
-        template = options[:rails][:template_engine]
-        css      = options[:rails][:stylesheet_engine]
-
-        [
-          "rails",
-          "resource_route",
-          "#{orm}:migration",
-          "#{orm}:model",
-          "#{test}:controller",
-          "#{test}:helper",
-          "#{test}:integration",
-          "#{test}:mailer",
-          "#{test}:model",
-          "#{test}:scaffold",
-          "#{test}:view",
-          "#{test}:job",
-          "#{template}:controller",
-          "#{template}:scaffold",
-          "#{template}:mailer",
-          "#{css}:scaffold",
-          "#{css}:assets",
-          "css:assets",
-          "css:scaffold"
-        ]
+      # Returns an array of generator namespaces that are hidden.
+      # Generator namespaces may be hidden for a variety of reasons.
+      # Some are aliased such as "rails:migration" and can be
+      # invoked with the shorter "migration", others are private to other generators
+      # such as "css:scaffold".
+      def hidden_namespaces
+        @hidden_namespaces ||= begin
+          orm      = options[:rails][:orm]
+          test     = options[:rails][:test_framework]
+          template = options[:rails][:template_engine]
+          css      = options[:rails][:stylesheet_engine]
+
+          [
+            "rails",
+            "resource_route",
+            "#{orm}:migration",
+            "#{orm}:model",
+            "#{test}:controller",
+            "#{test}:helper",
+            "#{test}:integration",
+            "#{test}:system",
+            "#{test}:mailer",
+            "#{test}:model",
+            "#{test}:scaffold",
+            "#{test}:view",
+            "#{test}:job",
+            "#{template}:controller",
+            "#{template}:scaffold",
+            "#{template}:mailer",
+            "#{css}:scaffold",
+            "#{css}:assets",
+            "css:assets",
+            "css:scaffold"
+          ]
+        end
       end
-    end
 
-    class << self
       def hide_namespaces(*namespaces)
         hidden_namespaces.concat(namespaces)
       end
       alias hide_namespace hide_namespaces
-    end
 
-    # Show help message with available generators.
-    def self.help(command = 'generate')
-      puts "Usage: rails #{command} GENERATOR [args] [options]"
-      puts
-      puts "General options:"
-      puts "  -h, [--help]     # Print generator's options and usage"
-      puts "  -p, [--pretend]  # Run but do not make any changes"
-      puts "  -f, [--force]    # Overwrite files that already exist"
-      puts "  -s, [--skip]     # Skip files that already exist"
-      puts "  -q, [--quiet]    # Suppress status output"
-      puts
-      puts "Please choose a generator below."
-      puts
-
-      print_generators
-    end
+      # Show help message with available generators.
+      def help(command = "generate")
+        puts "Usage: rails #{command} GENERATOR [args] [options]"
+        puts
+        puts "General options:"
+        puts "  -h, [--help]     # Print generator's options and usage"
+        puts "  -p, [--pretend]  # Run but do not make any changes"
+        puts "  -f, [--force]    # Overwrite files that already exist"
+        puts "  -s, [--skip]     # Skip files that already exist"
+        puts "  -q, [--quiet]    # Suppress status output"
+        puts
+        puts "Please choose a generator below."
+        puts
 
-    def self.public_namespaces
-      lookup!
-      subclasses.map(&:namespace)
-    end
+        print_generators
+      end
 
-    def self.print_generators
-      sorted_groups.each { |b, n| print_list(b, n) }
-    end
+      def public_namespaces
+        lookup!
+        subclasses.map(&:namespace)
+      end
 
-    def self.sorted_groups
-      namespaces = public_namespaces
-      namespaces.sort!
-      groups = Hash.new { |h,k| h[k] = [] }
-      namespaces.each do |namespace|
-        base = namespace.split(':').first
-        groups[base] << namespace
+      def print_generators
+        sorted_groups.each { |b, n| print_list(b, n) }
       end
-      rails = groups.delete("rails")
-      rails.map! { |n| n.sub(/^rails:/, '') }
-      rails.delete("app")
-      rails.delete("plugin")
 
-      hidden_namespaces.each { |n| groups.delete(n.to_s) }
+      def sorted_groups
+        namespaces = public_namespaces
+        namespaces.sort!
 
-      [["rails", rails]] + groups.sort.to_a
-    end
+        groups = Hash.new { |h, k| h[k] = [] }
+        namespaces.each do |namespace|
+          base = namespace.split(":").first
+          groups[base] << namespace
+        end
 
-    protected
-
-      # This code is based directly on the Text gem implementation
-      # Returns a value representing the "cost" of transforming str1 into str2
-      def self.levenshtein_distance str1, str2
-        s = str1
-        t = str2
-        n = s.length
-        m = t.length
-
-        return m if (0 == n)
-        return n if (0 == m)
-
-        d = (0..m).to_a
-        x = nil
-
-        # avoid duplicating an enumerable object in the loop
-        str2_codepoint_enumerable = str2.each_codepoint
-
-        str1.each_codepoint.with_index do |char1, i|
-          e = i+1
-
-          str2_codepoint_enumerable.with_index do |char2, j|
-            cost = (char1 == char2) ? 0 : 1
-            x = [
-                 d[j+1] + 1, # insertion
-                 e + 1,      # deletion
-                 d[j] + cost # substitution
-                ].min
-            d[j] = e
-            e = x
-          end
+        rails = groups.delete("rails")
+        rails.map! { |n| n.sub(/^rails:/, "") }
+        rails.delete("app")
+        rails.delete("plugin")
+        rails.delete("encrypted_secrets")
+        rails.delete("credentials")
 
-          d[m] = x
-        end
+        hidden_namespaces.each { |n| groups.delete(n.to_s) }
 
-        x
+        [[ "rails", rails ]] + groups.sort.to_a
       end
 
-      # Prints a list of generators.
-      def self.print_list(base, namespaces) #:nodoc:
-        namespaces = namespaces.reject do |n|
-          hidden_namespaces.include?(n)
+      # Rails finds namespaces similar to Thor, it only adds one rule:
+      #
+      # Generators names must end with "_generator.rb". This is required because Rails
+      # looks in load paths and loads the generator just before it's going to be used.
+      #
+      #   find_by_namespace :webrat, :rails, :integration
+      #
+      # Will search for the following generators:
+      #
+      #   "rails:webrat", "webrat:integration", "webrat"
+      #
+      # Notice that "rails:generators:webrat" could be loaded as well, what
+      # Rails looks for is the first and last parts of the namespace.
+      def find_by_namespace(name, base = nil, context = nil) #:nodoc:
+        lookups = []
+        lookups << "#{base}:#{name}"    if base
+        lookups << "#{name}:#{context}" if context
+
+        unless base || context
+          unless name.to_s.include?(?:)
+            lookups << "#{name}:#{name}"
+            lookups << "rails:#{name}"
+          end
+          lookups << "#{name}"
         end
 
-        return if namespaces.empty?
-        puts "#{base.camelize}:"
+        lookup(lookups)
 
-        namespaces.each do |namespace|
-          puts("  #{namespace}")
+        namespaces = Hash[subclasses.map { |klass| [klass.namespace, klass] }]
+        lookups.each do |namespace|
+
+          klass = namespaces[namespace]
+          return klass if klass
         end
 
-        puts
+        invoke_fallbacks_for(name, base) || invoke_fallbacks_for(context, name)
       end
 
-      # Try fallbacks for the given base.
-      def self.invoke_fallbacks_for(name, base) #:nodoc:
-        return nil unless base && fallbacks[base.to_sym]
-        invoked_fallbacks = []
+      # Receives a namespace, arguments and the behavior to invoke the generator.
+      # It's used as the default entry point for generate, destroy and update
+      # commands.
+      def invoke(namespace, args = ARGV, config = {})
+        names = namespace.to_s.split(":")
+        if klass = find_by_namespace(names.pop, names.any? && names.join(":"))
+          args << "--help" if args.empty? && klass.arguments.any?(&:required?)
+          klass.start(args, config)
+        else
+          options     = sorted_groups.flat_map(&:last)
+          suggestions = options.sort_by { |suggested| levenshtein_distance(namespace.to_s, suggested) }.first(3)
+          suggestions.map! { |s| "'#{s}'" }
+          msg =  "Could not find generator '#{namespace}'. ".dup
+          msg << "Maybe you meant #{ suggestions[0...-1].join(', ')} or #{suggestions[-1]}\n"
+          msg << "Run `rails generate --help` for more options."
+          puts msg
+        end
+      end
 
-        Array(fallbacks[base.to_sym]).each do |fallback|
-          next if invoked_fallbacks.include?(fallback)
-          invoked_fallbacks << fallback
+      private
 
-          klass = find_by_namespace(name, fallback)
-          return klass if klass
+        def print_list(base, namespaces) # :doc:
+          namespaces = namespaces.reject { |n| hidden_namespaces.include?(n) }
+          super
         end
 
-        nil
-      end
+        # Try fallbacks for the given base.
+        def invoke_fallbacks_for(name, base)
+          return nil unless base && fallbacks[base.to_sym]
+          invoked_fallbacks = []
+
+          Array(fallbacks[base.to_sym]).each do |fallback|
+            next if invoked_fallbacks.include?(fallback)
+            invoked_fallbacks << fallback
 
-      # Receives namespaces in an array and tries to find matching generators
-      # in the load path.
-      def self.lookup(namespaces) #:nodoc:
-        paths = namespaces_to_paths(namespaces)
-
-        paths.each do |raw_path|
-          ["rails/generators", "generators"].each do |base|
-            path = "#{base}/#{raw_path}_generator"
-
-            begin
-              require path
-              return
-            rescue LoadError => e
-              raise unless e.message =~ /#{Regexp.escape(path)}$/
-            rescue Exception => e
-              warn "[WARNING] Could not load generator #{path.inspect}. Error: #{e.message}.\n#{e.backtrace.join("\n")}"
-            end
+            klass = find_by_namespace(name, fallback)
+            return klass if klass
           end
+
+          nil
         end
-      end
 
-      # This will try to load any generator in the load path to show in help.
-      def self.lookup! #:nodoc:
-        $LOAD_PATH.each do |base|
-          Dir[File.join(base, "{rails/generators,generators}", "**", "*_generator.rb")].each do |path|
-            begin
-              path = path.sub("#{base}/", "")
-              require path
-            rescue Exception
-              # No problem
-            end
-          end
+        def command_type # :doc:
+          @command_type ||= "generator"
         end
-      end
 
-      # Convert namespaces to paths by replacing ":" for "/" and adding
-      # an extra lookup. For example, "rails:model" should be searched
-      # in both: "rails/model/model_generator" and "rails/model_generator".
-      def self.namespaces_to_paths(namespaces) #:nodoc:
-        paths = []
-        namespaces.each do |namespace|
-          pieces = namespace.split(":")
-          paths << pieces.dup.push(pieces.last).join("/")
-          paths << pieces.join("/")
+        def lookup_paths # :doc:
+          @lookup_paths ||= %w( rails/generators generators )
         end
-        paths.uniq!
-        paths
-      end
+
+        def file_lookup_paths # :doc:
+          @file_lookup_paths ||= [ "{#{lookup_paths.join(',')}}", "**", "*_generator.rb" ]
+        end
+    end
   end
 end
diff --git a/railties/lib/rails/generators/actions.rb b/railties/lib/rails/generators/actions.rb
index c947c062fa..3362bf629a 100644
--- a/railties/lib/rails/generators/actions.rb
+++ b/railties/lib/rails/generators/actions.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module Rails
   module Generators
     module Actions
@@ -11,17 +13,22 @@ module Rails
       #
       #   gem "rspec", group: :test
       #   gem "technoweenie-restful-authentication", lib: "restful-authentication", source: "http://gems.github.com/"
-      #   gem "rails", "3.0", git: "git://github.com/rails/rails"
+      #   gem "rails", "3.0", git: "https://github.com/rails/rails"
+      #   gem "RedCloth", ">= 4.1.0", "< 4.2.0"
       def gem(*args)
         options = args.extract_options!
-        name, version = args
+        name, *versions = args
 
         # Set the message to be shown in logs. Uses the git repo if one is given,
         # otherwise use name (version).
         parts, message = [ quote(name) ], name.dup
-        if version ||= options.delete(:version)
-          parts   << quote(version)
-          message << " (#{version})"
+
+        if versions = versions.any? ? versions : options.delete(:version)
+          _versions = Array(versions)
+          _versions.each do |version|
+            parts << quote(version)
+          end
+          message << " (#{_versions.join(", ")})"
         end
         message = options[:git] if options[:git]
 
@@ -68,7 +75,7 @@ module Rails
       #   add_source "http://gems.github.com/" do
       #     gem "rspec-rails"
       #   end
-      def add_source(source, options={}, &block)
+      def add_source(source, options = {}, &block)
         log :source, source
 
         in_root do
@@ -96,17 +103,17 @@ module Rails
       #   environment(nil, env: "development") do
       #     "config.action_controller.asset_host = 'localhost:3000'"
       #   end
-      def environment(data=nil, options={})
-        sentinel = /class [a-z_:]+ < Rails::Application/i
-        env_file_sentinel = /Rails\.application\.configure do/
-        data = yield if !data && block_given?
+      def environment(data = nil, options = {})
+        sentinel = "class Application < Rails::Application\n"
+        env_file_sentinel = "Rails.application.configure do\n"
+        data ||= yield if block_given?
 
         in_root do
           if options[:env].nil?
-            inject_into_file 'config/application.rb', "\n    #{data}", after: sentinel, verbose: false
+            inject_into_file "config/application.rb", optimize_indentation(data, 4), after: sentinel, verbose: false
           else
             Array(options[:env]).each do |env|
-              inject_into_file "config/environments/#{env}.rb", "\n  #{data}", after: env_file_sentinel, verbose: false
+              inject_into_file "config/environments/#{env}.rb", optimize_indentation(data, 2), after: env_file_sentinel, verbose: false
             end
           end
         end
@@ -118,7 +125,7 @@ module Rails
       #   git :init
       #   git add: "this.file that.rb"
       #   git add: "onefile.rb", rm: "badfile.cxx"
-      def git(commands={})
+      def git(commands = {})
         if commands.is_a?(Symbol)
           run "git #{commands}"
         else
@@ -137,12 +144,13 @@ module Rails
       #   end
       #
       #   vendor("foreign.rb", "# Foreign code is fun")
-      def vendor(filename, data=nil, &block)
+      def vendor(filename, data = nil)
         log :vendor, filename
-        create_file("vendor/#{filename}", data, verbose: false, &block)
+        data ||= yield if block_given?
+        create_file("vendor/#{filename}", optimize_indentation(data), verbose: false)
       end
 
-      # Create a new file in the lib/ directory. Code can be specified
+      # Create a new file in the <tt>lib/</tt> directory. Code can be specified
       # in a block or a data string can be given.
       #
       #   lib("crypto.rb") do
@@ -150,9 +158,10 @@ module Rails
       #   end
       #
       #   lib("foreign.rb", "# Foreign code is fun")
-      def lib(filename, data=nil, &block)
+      def lib(filename, data = nil)
         log :lib, filename
-        create_file("lib/#{filename}", data, verbose: false, &block)
+        data ||= yield if block_given?
+        create_file("lib/#{filename}", optimize_indentation(data), verbose: false)
       end
 
       # Create a new +Rakefile+ with the provided code (either in a block or a string).
@@ -170,9 +179,10 @@ module Rails
       #   end
       #
       #   rakefile('seed.rake', 'puts "Planting seeds"')
-      def rakefile(filename, data=nil, &block)
+      def rakefile(filename, data = nil)
         log :rakefile, filename
-        create_file("lib/tasks/#{filename}", data, verbose: false, &block)
+        data ||= yield if block_given?
+        create_file("lib/tasks/#{filename}", optimize_indentation(data), verbose: false)
       end
 
       # Create a new initializer with the provided code (either in a block or a string).
@@ -188,9 +198,10 @@ module Rails
       #   end
       #
       #   initializer("api.rb", "API_KEY = '123456'")
-      def initializer(filename, data=nil, &block)
+      def initializer(filename, data = nil)
         log :initializer, filename
-        create_file("config/initializers/#{filename}", data, verbose: false, &block)
+        data ||= yield if block_given?
+        create_file("config/initializers/#{filename}", optimize_indentation(data), verbose: false)
       end
 
       # Generate something using a generator from Rails or a plugin.
@@ -210,16 +221,18 @@ module Rails
       #   rake("db:migrate")
       #   rake("db:migrate", env: "production")
       #   rake("gems:install", sudo: true)
-      def rake(command, options={})
+      #   rake("gems:install", capture: true)
+      def rake(command, options = {})
         execute_command :rake, command, options
       end
 
       # Runs the supplied rake task (invoked with 'rails ...')
       #
-      #   rails("db:migrate")
-      #   rails("db:migrate", env: "production")
-      #   rails("gems:install", sudo: true)
-      def rails_command(command, options={})
+      #   rails_command("db:migrate")
+      #   rails_command("db:migrate", env: "production")
+      #   rails_command("gems:install", sudo: true)
+      #   rails_command("gems:install", capture: true)
+      def rails_command(command, options = {})
         execute_command :rails, command, options
       end
 
@@ -227,6 +240,7 @@ module Rails
       #
       #   capify!
       def capify!
+        ActiveSupport::Deprecation.warn("`capify!` is deprecated and will be removed in the next version of Rails.")
         log :capify, ""
         in_root { run("#{extify(:capify)} .", verbose: false) }
       end
@@ -239,7 +253,7 @@ module Rails
         sentinel = /\.routes\.draw do\s*\n/m
 
         in_root do
-          inject_into_file 'config/routes.rb', "  #{routing_code}\n", { after: sentinel, verbose: false, force: false }
+          inject_into_file "config/routes.rb", optimize_indentation(routing_code, 2), after: sentinel, verbose: false, force: false
         end
       end
 
@@ -260,33 +274,36 @@ module Rails
         @after_bundle_callbacks << block
       end
 
-      protected
+      private
 
         # Define log for backwards compatibility. If just one argument is sent,
         # invoke say, otherwise invoke say_status. Differently from say and
         # similarly to say_status, this method respects the quiet? option given.
-        def log(*args)
+        def log(*args) # :doc:
           if args.size == 1
             say args.first.to_s unless options.quiet?
           else
-            args << (self.behavior == :invoke ? :green : :red)
+            args << (behavior == :invoke ? :green : :red)
             say_status(*args)
           end
         end
 
-
         # Runs the supplied command using either "rake ..." or "rails ..."
         # based on the executor parameter provided.
-        def execute_command(executor, command, options={})
+        def execute_command(executor, command, options = {}) # :doc:
           log executor, command
-          env  = options[:env] || ENV["RAILS_ENV"] || 'development'
-          sudo = options[:sudo] && RbConfig::CONFIG['host_os'] !~ /mswin|mingw/ ? 'sudo ' : ''
-          in_root { run("#{sudo}#{extify(executor)} #{command} RAILS_ENV=#{env}", verbose: false) }
+          env  = options[:env] || ENV["RAILS_ENV"] || "development"
+          sudo = options[:sudo] && !Gem.win_platform? ? "sudo " : ""
+          config = { verbose: false }
+
+          config.merge!(capture: options[:capture]) if options[:capture]
+
+          in_root { run("#{sudo}#{extify(executor)} #{command} RAILS_ENV=#{env}", config) }
         end
 
         # Add an extension to the given name based on the platform.
-        def extify(name)
-          if RbConfig::CONFIG['host_os'] =~ /mswin|mingw/
+        def extify(name) # :doc:
+          if Gem.win_platform?
             "#{name}.bat"
           else
             name
@@ -295,7 +312,7 @@ module Rails
 
         # Surround string with single quotes if there is no quotes.
         # Otherwise fall back to double quotes
-        def quote(value)
+        def quote(value) # :doc:
           return value.inspect unless value.is_a? String
 
           if value.include?("'")
@@ -304,6 +321,17 @@ module Rails
             "'#{value}'"
           end
         end
+
+        # Returns optimized string with indentation
+        def optimize_indentation(value, amount = 0) # :doc:
+          return "#{value}\n" unless value.is_a?(String)
+
+          if value.lines.size > 1
+            value.strip_heredoc.indent(amount)
+          else
+            "#{value.strip.indent(amount)}\n"
+          end
+        end
     end
   end
 end
diff --git a/railties/lib/rails/generators/actions/create_migration.rb b/railties/lib/rails/generators/actions/create_migration.rb
index 6c5b55466d..05bc242447 100644
--- a/railties/lib/rails/generators/actions/create_migration.rb
+++ b/railties/lib/rails/generators/actions/create_migration.rb
@@ -1,11 +1,12 @@
-require 'fileutils'
-require 'thor/actions'
+# frozen_string_literal: true
+
+require "fileutils"
+require "thor/actions"
 
 module Rails
   module Generators
     module Actions
       class CreateMigration < Thor::Actions::CreateFile #:nodoc:
-
         def migration_dir
           File.dirname(@destination)
         end
@@ -38,32 +39,32 @@ module Rails
         end
         alias :exists? :existing_migration
 
-        protected
+        private
 
-        def on_conflict_behavior
-          options = base.options.merge(config)
-          if identical?
-            say_status :identical, :blue, relative_existing_migration
-          elsif options[:force]
-            say_status :remove, :green, relative_existing_migration
-            say_status :create, :green
-            unless pretend?
-              ::FileUtils.rm_rf(existing_migration)
-              yield
+          def on_conflict_behavior # :doc:
+            options = base.options.merge(config)
+            if identical?
+              say_status :identical, :blue, relative_existing_migration
+            elsif options[:force]
+              say_status :remove, :green, relative_existing_migration
+              say_status :create, :green
+              unless pretend?
+                ::FileUtils.rm_rf(existing_migration)
+                yield
+              end
+            elsif options[:skip]
+              say_status :skip, :yellow
+            else
+              say_status :conflict, :red
+              raise Error, "Another migration is already named #{migration_file_name}: " \
+                "#{existing_migration}. Use --force to replace this migration " \
+                "or --skip to ignore conflicted file."
             end
-          elsif options[:skip]
-            say_status :skip, :yellow
-          else
-            say_status :conflict, :red
-            raise Error, "Another migration is already named #{migration_file_name}: " +
-              "#{existing_migration}. Use --force to replace this migration " +
-              "or --skip to ignore conflicted file."
           end
-        end
 
-        def say_status(status, color, message = relative_destination)
-          base.shell.say_status(status, message, color) if config[:verbose]
-        end
+          def say_status(status, color, message = relative_destination) # :doc:
+            base.shell.say_status(status, message, color) if config[:verbose]
+          end
       end
     end
   end
diff --git a/railties/lib/rails/generators/active_model.rb b/railties/lib/rails/generators/active_model.rb
index 6183944bb0..8df8eb2438 100644
--- a/railties/lib/rails/generators/active_model.rb
+++ b/railties/lib/rails/generators/active_model.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module Rails
   module Generators
     # ActiveModel is a class to be implemented by each ORM to allow Rails to
@@ -39,13 +41,13 @@ module Rails
       # GET edit
       # PATCH/PUT update
       # DELETE destroy
-      def self.find(klass, params=nil)
+      def self.find(klass, params = nil)
         "#{klass}.find(#{params})"
       end
 
       # GET new
       # POST create
-      def self.build(klass, params=nil)
+      def self.build(klass, params = nil)
         if params
           "#{klass}.new(#{params})"
         else
@@ -59,7 +61,7 @@ module Rails
       end
 
       # PATCH/PUT update
-      def update(params=nil)
+      def update(params = nil)
         "#{name}.update(#{params})"
       end
 
diff --git a/railties/lib/rails/generators/app_base.rb b/railties/lib/rails/generators/app_base.rb
index f0a3289563..400f954dcd 100644
--- a/railties/lib/rails/generators/app_base.rb
+++ b/railties/lib/rails/generators/app_base.rb
@@ -1,16 +1,18 @@
-require 'fileutils'
-require 'digest/md5'
-require 'active_support/core_ext/string/strip'
-require 'rails/version' unless defined?(Rails::VERSION)
-require 'open-uri'
-require 'uri'
-require 'rails/generators'
-require 'active_support/core_ext/array/extract_options'
+# frozen_string_literal: true
+
+require "fileutils"
+require "digest/md5"
+require "active_support/core_ext/string/strip"
+require "rails/version" unless defined?(Rails::VERSION)
+require "open-uri"
+require "uri"
+require "rails/generators"
+require "active_support/core_ext/array/extract_options"
 
 module Rails
   module Generators
     class AppBase < Base # :nodoc:
-      DATABASES = %w( mysql oracle postgresql sqlite3 frontbase ibm_db sqlserver )
+      DATABASES = %w( mysql postgresql sqlite3 oracle frontbase ibm_db sqlserver )
       JDBC_DATABASES = %w( jdbcmysql jdbcsqlite3 jdbcpostgresql jdbc )
       DATABASES.concat(JDBC_DATABASES)
 
@@ -24,72 +26,81 @@ module Rails
       end
 
       def self.add_shared_options_for(name)
-        class_option :template,           type: :string, aliases: '-m',
-                                          desc: "Path to some #{name} template (can be a filesystem path or URL)"
+        class_option :template,            type: :string, aliases: "-m",
+                                           desc: "Path to some #{name} template (can be a filesystem path or URL)"
+
+        class_option :database,            type: :string, aliases: "-d", default: "sqlite3",
+                                           desc: "Preconfigure for selected database (options: #{DATABASES.join('/')})"
+
+        class_option :skip_yarn,           type: :boolean, default: false,
+                                           desc: "Don't use Yarn for managing JavaScript dependencies"
+
+        class_option :skip_gemfile,        type: :boolean, default: false,
+                                           desc: "Don't create a Gemfile"
 
-        class_option :database,           type: :string, aliases: '-d', default: 'sqlite3',
-                                          desc: "Preconfigure for selected database (options: #{DATABASES.join('/')})"
+        class_option :skip_git,            type: :boolean, aliases: "-G", default: false,
+                                           desc: "Skip .gitignore file"
 
-        class_option :javascript,         type: :string, aliases: '-j', default: 'jquery',
-                                          desc: 'Preconfigure for selected JavaScript library'
+        class_option :skip_keeps,          type: :boolean, default: false,
+                                           desc: "Skip source control .keep files"
 
-        class_option :skip_gemfile,       type: :boolean, default: false,
-                                          desc: "Don't create a Gemfile"
+        class_option :skip_action_mailer,  type: :boolean, aliases: "-M",
+                                           default: false,
+                                           desc: "Skip Action Mailer files"
 
-        class_option :skip_bundle,        type: :boolean, aliases: '-B', default: false,
-                                          desc: "Don't run bundle install"
+        class_option :skip_active_record,  type: :boolean, aliases: "-O", default: false,
+                                           desc: "Skip Active Record files"
 
-        class_option :skip_git,           type: :boolean, aliases: '-G', default: false,
-                                          desc: 'Skip .gitignore file'
+        class_option :skip_active_storage, type: :boolean, default: false,
+                                           desc: "Skip Active Storage files"
 
-        class_option :skip_keeps,         type: :boolean, default: false,
-                                          desc: 'Skip source control .keep files'
+        class_option :skip_puma,           type: :boolean, aliases: "-P", default: false,
+                                           desc: "Skip Puma related files"
 
-        class_option :skip_action_mailer, type: :boolean, aliases: "-M",
-                                          default: false,
-                                          desc: "Skip Action Mailer files"
+        class_option :skip_action_cable,   type: :boolean, aliases: "-C", default: false,
+                                           desc: "Skip Action Cable files"
 
-        class_option :skip_active_record, type: :boolean, aliases: '-O', default: false,
-                                          desc: 'Skip Active Record files'
+        class_option :skip_sprockets,      type: :boolean, aliases: "-S", default: false,
+                                           desc: "Skip Sprockets files"
 
-        class_option :skip_puma,          type: :boolean, aliases: '-P', default: false,
-                                          desc: 'Skip Puma related files'
+        class_option :skip_spring,         type: :boolean, default: false,
+                                           desc: "Don't install Spring application preloader"
 
-        class_option :skip_action_cable,  type: :boolean, aliases: '-C', default: false,
-                                          desc: 'Skip Action Cable files'
+        class_option :skip_listen,         type: :boolean, default: false,
+                                           desc: "Don't generate configuration that depends on the listen gem"
 
-        class_option :skip_sprockets,     type: :boolean, aliases: '-S', default: false,
-                                          desc: 'Skip Sprockets files'
+        class_option :skip_coffee,         type: :boolean, default: false,
+                                           desc: "Don't use CoffeeScript"
 
-        class_option :skip_spring,        type: :boolean, default: false,
-                                          desc: "Don't install Spring application preloader"
+        class_option :skip_javascript,     type: :boolean, aliases: "-J", default: false,
+                                           desc: "Skip JavaScript files"
 
-        class_option :skip_listen,        type: :boolean, default: false,
-                                          desc: "Don't generate configuration that depends on the listen gem"
+        class_option :skip_turbolinks,     type: :boolean, default: false,
+                                           desc: "Skip turbolinks gem"
 
-        class_option :skip_javascript,    type: :boolean, aliases: '-J', default: false,
-                                          desc: 'Skip JavaScript files'
+        class_option :skip_test,           type: :boolean, aliases: "-T", default: false,
+                                           desc: "Skip test files"
 
-        class_option :skip_turbolinks,    type: :boolean, default: false,
-                                          desc: 'Skip turbolinks gem'
+        class_option :skip_system_test,    type: :boolean, default: false,
+                                           desc: "Skip system test files"
 
-        class_option :skip_test,          type: :boolean, aliases: '-T', default: false,
-                                          desc: 'Skip test files'
+        class_option :skip_bootsnap,       type: :boolean, default: false,
+                                           desc: "Skip bootsnap gem"
 
-        class_option :dev,                type: :boolean, default: false,
-                                          desc: "Setup the #{name} with Gemfile pointing to your Rails checkout"
+        class_option :dev,                 type: :boolean, default: false,
+                                           desc: "Setup the #{name} with Gemfile pointing to your Rails checkout"
 
-        class_option :edge,               type: :boolean, default: false,
-                                          desc: "Setup the #{name} with Gemfile pointing to Rails repository"
+        class_option :edge,                type: :boolean, default: false,
+                                           desc: "Setup the #{name} with Gemfile pointing to Rails repository"
 
-        class_option :rc,                 type: :string, default: nil,
-                                          desc: "Path to file containing extra configuration options for rails command"
+        class_option :rc,                  type: :string, default: nil,
+                                           desc: "Path to file containing extra configuration options for rails command"
 
-        class_option :no_rc,              type: :boolean, default: false,
-                                          desc: 'Skip loading of extra configuration options from .railsrc file'
+        class_option :no_rc,               type: :boolean, default: false,
+                                           desc: "Skip loading of extra configuration options from .railsrc file"
 
-        class_option :help,               type: :boolean, aliases: '-h', group: :rails,
-                                          desc: 'Show this help message and quit'
+        class_option :help,                type: :boolean, aliases: "-h", group: :rails,
+                                           desc: "Show this help message and quit"
       end
 
       def initialize(*args)
@@ -99,9 +110,9 @@ module Rails
         convert_database_option_for_jruby
       end
 
-    protected
+    private
 
-      def gemfile_entry(name, *args)
+      def gemfile_entry(name, *args) # :doc:
         options = args.extract_options!
         version = args.first
         github = options[:github]
@@ -117,11 +128,12 @@ module Rails
         self
       end
 
-      def gemfile_entries
+      def gemfile_entries # :doc:
         [rails_gemfile_entry,
          database_gemfile_entry,
          webserver_gemfile_entry,
          assets_gemfile_entry,
+         webpacker_gemfile_entry,
          javascript_gemfile_entry,
          jbuilder_gemfile_entry,
          psych_gemfile_entry,
@@ -129,13 +141,13 @@ module Rails
          @extra_entries].flatten.find_all(&@gem_filter)
       end
 
-      def add_gem_entry_filter
+      def add_gem_entry_filter # :doc:
         @gem_filter = lambda { |next_filter, entry|
           yield(entry) && next_filter.call(entry)
         }.curry[@gem_filter]
       end
 
-      def builder
+      def builder # :doc:
         @builder ||= begin
           builder_class = get_builder_class
           builder_class.include(ActionMethods)
@@ -143,62 +155,85 @@ module Rails
         end
       end
 
-      def build(meth, *args)
+      def build(meth, *args) # :doc:
         builder.send(meth, *args) if builder.respond_to?(meth)
       end
 
-      def create_root
+      def create_root # :doc:
         valid_const?
 
-        empty_directory '.'
+        empty_directory "."
         FileUtils.cd(destination_root) unless options[:pretend]
       end
 
-      def apply_rails_template
+      def apply_rails_template # :doc:
         apply rails_template if rails_template
       rescue Thor::Error, LoadError, Errno::ENOENT => e
         raise Error, "The template [#{rails_template}] could not be loaded. Error: #{e}"
       end
 
-      def set_default_accessors!
+      def set_default_accessors! # :doc:
         self.destination_root = File.expand_path(app_path, destination_root)
-        self.rails_template = case options[:template]
+        self.rails_template = \
+          case options[:template]
           when /^https?:\/\//
             options[:template]
           when String
             File.expand_path(options[:template], Dir.pwd)
           else
             options[:template]
-        end
+          end
       end
 
-      def database_gemfile_entry
+      def database_gemfile_entry # :doc:
         return [] if options[:skip_active_record]
         gem_name, gem_version = gem_for_database
         GemfileEntry.version gem_name, gem_version,
                             "Use #{options[:database]} as the database for Active Record"
       end
 
-      def webserver_gemfile_entry
+      def webserver_gemfile_entry # :doc:
         return [] if options[:skip_puma]
-        comment = 'Use Puma as the app server'
-        GemfileEntry.new('puma', '~> 3.0', comment)
+        comment = "Use Puma as the app server"
+        GemfileEntry.new("puma", "~> 3.11", comment)
       end
 
-      def include_all_railties?
-        options.values_at(:skip_active_record, :skip_action_mailer, :skip_test, :skip_sprockets, :skip_action_cable).none?
+      def include_all_railties? # :doc:
+        [
+          options.values_at(
+            :skip_active_record,
+            :skip_action_mailer,
+            :skip_test,
+            :skip_sprockets,
+            :skip_action_cable
+          ),
+          skip_active_storage?
+        ].flatten.none?
       end
 
-      def comment_if(value)
-        options[value] ? '# ' : ''
+      def comment_if(value) # :doc:
+        question = "#{value}?"
+
+        comment =
+          if respond_to?(question, true)
+            send(question)
+          else
+            options[value]
+          end
+
+        comment ? "# " : ""
       end
 
-      def keeps?
+      def keeps? # :doc:
         !options[:skip_keeps]
       end
 
-      def sqlite3?
-        !options[:skip_active_record] && options[:database] == 'sqlite3'
+      def sqlite3? # :doc:
+        !options[:skip_active_record] && options[:database] == "sqlite3"
+      end
+
+      def skip_active_storage? # :doc:
+        options[:skip_active_storage] || options[:skip_active_record]
       end
 
       class GemfileEntry < Struct.new(:name, :version, :comment, :options, :commented_out)
@@ -234,44 +269,41 @@ module Rails
       end
 
       def rails_gemfile_entry
-        dev_edge_common = [
-        ]
         if options.dev?
           [
-            GemfileEntry.path('rails', Rails::Generators::RAILS_DEV_PATH)
-          ] + dev_edge_common
+            GemfileEntry.path("rails", Rails::Generators::RAILS_DEV_PATH)
+          ]
         elsif options.edge?
           [
-            GemfileEntry.github('rails', 'rails/rails')
-          ] + dev_edge_common
+            GemfileEntry.github("rails", "rails/rails")
+          ]
         else
-          [GemfileEntry.version('rails',
+          [GemfileEntry.version("rails",
                             rails_version_specifier,
                             "Bundle edge Rails instead: gem 'rails', github: 'rails/rails'")]
         end
       end
 
       def rails_version_specifier(gem_version = Rails.gem_version)
-        if gem_version.prerelease?
-          next_series = gem_version
-          next_series = next_series.bump while next_series.segments.size > 2
-
-          [">= #{gem_version}", "< #{next_series}"]
-        elsif gem_version.segments.size == 3
+        if gem_version.segments.size == 3 || gem_version.release.segments.size == 3
+          # ~> 1.2.3
+          # ~> 1.2.3.pre4
           "~> #{gem_version}"
         else
+          # ~> 1.2.3, >= 1.2.3.4
+          # ~> 1.2.3, >= 1.2.3.4.pre5
           patch = gem_version.segments[0, 3].join(".")
           ["~> #{patch}", ">= #{gem_version}"]
         end
       end
 
       def gem_for_database
-        # %w( mysql oracle postgresql sqlite3 frontbase ibm_db sqlserver jdbcmysql jdbcsqlite3 jdbcpostgresql )
+        # %w( mysql postgresql sqlite3 oracle frontbase ibm_db sqlserver jdbcmysql jdbcsqlite3 jdbcpostgresql )
         case options[:database]
-        when "oracle"         then ["ruby-oci8", nil]
+        when "mysql"          then ["mysql2", ["~> 0.4.4"]]
         when "postgresql"     then ["pg", ["~> 0.18"]]
+        when "oracle"         then ["activerecord-oracle_enhanced-adapter", nil]
         when "frontbase"      then ["ruby-frontbase", nil]
-        when "mysql"          then ["mysql2", [">= 0.3.18", "< 0.5"]]
         when "sqlserver"      then ["activerecord-sqlserver-adapter", nil]
         when "jdbcmysql"      then ["activerecord-jdbcmysql-adapter", nil]
         when "jdbcsqlite3"    then ["activerecord-jdbcsqlite3-adapter", nil]
@@ -284,7 +316,6 @@ module Rails
       def convert_database_option_for_jruby
         if defined?(JRUBY_VERSION)
           case options[:database]
-          when "oracle"     then options[:database].replace "jdbc"
           when "postgresql" then options[:database].replace "jdbcpostgresql"
           when "mysql"      then options[:database].replace "jdbcmysql"
           when "sqlite3"    then options[:database].replace "jdbcsqlite3"
@@ -296,35 +327,43 @@ module Rails
         return [] if options[:skip_sprockets]
 
         gems = []
-        gems << GemfileEntry.github('sass-rails', 'rails/sass-rails', nil,
-                                     'Use SCSS for stylesheets')
+        gems << GemfileEntry.version("sass-rails", "~> 5.0",
+                                     "Use SCSS for stylesheets")
 
-        gems << GemfileEntry.version('uglifier',
-                                   '>= 1.3.0',
-                                   'Use Uglifier as compressor for JavaScript assets')
+        if !options[:skip_javascript]
+          gems << GemfileEntry.version("uglifier",
+                                     ">= 1.3.0",
+                                     "Use Uglifier as compressor for JavaScript assets")
+        end
 
         gems
       end
 
+      def webpacker_gemfile_entry
+        return [] unless options[:webpack]
+
+        comment = "Transpile app-like JavaScript. Read more: https://github.com/rails/webpacker"
+        GemfileEntry.new "webpacker", nil, comment
+      end
+
       def jbuilder_gemfile_entry
-        comment = 'Build JSON APIs with ease. Read more: https://github.com/rails/jbuilder'
-        GemfileEntry.new 'jbuilder', '~> 2.5', comment, {}, options[:api]
+        comment = "Build JSON APIs with ease. Read more: https://github.com/rails/jbuilder"
+        GemfileEntry.new "jbuilder", "~> 2.5", comment, {}, options[:api]
       end
 
       def coffee_gemfile_entry
-        GemfileEntry.github 'coffee-rails', 'rails/coffee-rails', nil, 'Use CoffeeScript for .coffee assets and views'
+        GemfileEntry.version "coffee-rails", "~> 4.2", "Use CoffeeScript for .coffee assets and views"
       end
 
       def javascript_gemfile_entry
         if options[:skip_javascript] || options[:skip_sprockets]
           []
         else
-          gems = [coffee_gemfile_entry, javascript_runtime_gemfile_entry]
-          gems << GemfileEntry.version("#{options[:javascript]}-rails", nil,
-                                       "Use #{options[:javascript]} as the JavaScript library")
+          gems = [javascript_runtime_gemfile_entry]
+          gems << coffee_gemfile_entry unless options[:skip_coffee]
 
           unless options[:skip_turbolinks]
-            gems << GemfileEntry.version("turbolinks", "~> 5.x",
+            gems << GemfileEntry.version("turbolinks", "~> 5",
              "Turbolinks makes navigating your web application faster. Read more: https://github.com/turbolinks/turbolinks")
           end
 
@@ -333,27 +372,29 @@ module Rails
       end
 
       def javascript_runtime_gemfile_entry
-        comment = 'See https://github.com/rails/execjs#readme for more supported runtimes'
+        comment = "See https://github.com/rails/execjs#readme for more supported runtimes"
         if defined?(JRUBY_VERSION)
-          GemfileEntry.version 'therubyrhino', nil, comment
+          GemfileEntry.version "therubyrhino", nil, comment
+        elsif RUBY_PLATFORM =~ /mingw|mswin/
+          GemfileEntry.version "duktape", nil, comment
         else
-          GemfileEntry.new 'therubyracer', nil, comment, { platforms: :ruby }, true
+          GemfileEntry.new "mini_racer", nil, comment, { platforms: :ruby }, true
         end
       end
 
       def psych_gemfile_entry
         return [] unless defined?(Rubinius)
 
-        comment = 'Use Psych as the YAML engine, instead of Syck, so serialized ' \
-                  'data can be read safely from different rubies (see http://git.io/uuLVag)'
-        GemfileEntry.new('psych', '~> 2.0', comment, platforms: :rbx)
+        comment = "Use Psych as the YAML engine, instead of Syck, so serialized " \
+                  "data can be read safely from different rubies (see http://git.io/uuLVag)"
+        GemfileEntry.new("psych", "~> 2.0", comment, platforms: :rbx)
       end
 
       def cable_gemfile_entry
         return [] if options[:skip_action_cable]
-        comment = 'Use Redis adapter to run Action Cable in production'
+        comment = "Use Redis adapter to run Action Cable in production"
         gems = []
-        gems << GemfileEntry.new("redis", '~> 3.0', comment, {}, true)
+        gems << GemfileEntry.new("redis", "~> 4.0", comment, {}, true)
         gems
       end
 
@@ -368,9 +409,9 @@ module Rails
         # We unset temporary bundler variables to load proper bundler and Gemfile.
         #
         # Thanks to James Tucker for the Gem tricks involved in this call.
-        _bundle_command = Gem.bin_path('bundler', 'bundle')
+        _bundle_command = Gem.bin_path("bundler", "bundle")
 
-        require 'bundler'
+        require "bundler"
         Bundler.with_clean_env do
           full_command = %Q["#{Gem.ruby}" "#{_bundle_command}" #{command}]
           if options[:quiet]
@@ -389,16 +430,31 @@ module Rails
         !options[:skip_spring] && !options.dev? && Process.respond_to?(:fork) && !RUBY_PLATFORM.include?("cygwin")
       end
 
+      def depends_on_system_test?
+        !(options[:skip_system_test] || options[:skip_test] || options[:api])
+      end
+
       def depend_on_listen?
         !options[:skip_listen] && os_supports_listen_out_of_the_box?
       end
 
+      def depend_on_bootsnap?
+        !options[:skip_bootsnap] && !options[:dev]
+      end
+
       def os_supports_listen_out_of_the_box?
-        RbConfig::CONFIG['host_os'] =~ /darwin|linux/
+        RbConfig::CONFIG["host_os"] =~ /darwin|linux/
       end
 
       def run_bundle
-        bundle_command('install') if bundle_install?
+        bundle_command("install") if bundle_install?
+      end
+
+      def run_webpack
+        if !(webpack = options[:webpack]).nil?
+          rails_command "webpacker:install"
+          rails_command "webpacker:install:#{webpack}" unless webpack == "webpack"
+        end
       end
 
       def generate_spring_binstubs
@@ -407,6 +463,16 @@ module Rails
         end
       end
 
+      def run_active_storage
+        unless skip_active_storage?
+          if bundle_install?
+            rails_command "active_storage:install", capture: options[:quiet]
+          else
+            log("Active Storage installation was skipped. Please run `bin/rails active_storage:install` to install Active Storage files.")
+          end
+        end
+      end
+
       def empty_directory_with_keep_file(destination, config = {})
         empty_directory(destination, config)
         keep_file(destination)
diff --git a/railties/lib/rails/generators/base.rb b/railties/lib/rails/generators/base.rb
index c72ec400a0..5523a3f659 100644
--- a/railties/lib/rails/generators/base.rb
+++ b/railties/lib/rails/generators/base.rb
@@ -1,5 +1,7 @@
+# frozen_string_literal: true
+
 begin
-  require 'thor/group'
+  require "thor/group"
 rescue LoadError
   puts "Thor is not available.\nIf you ran this command from a git checkout " \
        "of Rails, please make sure thor is installed,\nand run this command " \
@@ -16,18 +18,21 @@ module Rails
       include Thor::Actions
       include Rails::Generators::Actions
 
+      class_option :skip_namespace, type: :boolean, default: false,
+                                    desc: "Skip namespace (affects only isolated applications)"
+
       add_runtime_options!
       strict_args_position!
 
       # Returns the source root for this generator using default_source_root as default.
-      def self.source_root(path=nil)
+      def self.source_root(path = nil)
         @_source_root = path if path
         @_source_root ||= default_source_root
       end
 
       # Tries to get the description from a USAGE file one folder above the source
       # root otherwise uses a default description.
-      def self.desc(description=nil)
+      def self.desc(description = nil)
         return super if description
 
         @desc ||= if usage_path
@@ -40,15 +45,15 @@ module Rails
       # Convenience method to get the namespace from the class name. It's the
       # same as Thor default except that the Generator at the end of the class
       # is removed.
-      def self.namespace(name=nil)
+      def self.namespace(name = nil)
         return super if name
-        @namespace ||= super.sub(/_generator$/, '').sub(/:generators:/, ':')
+        @namespace ||= super.sub(/_generator$/, "").sub(/:generators:/, ":")
       end
 
       # Convenience method to hide this generator from the available ones when
       # running rails generator command.
       def self.hide!
-        Rails::Generators.hide_namespace self.namespace
+        Rails::Generators.hide_namespace(namespace)
       end
 
       # Invoke a generator based on the value supplied by the user to the
@@ -168,7 +173,7 @@ module Rails
         names.each do |name|
           unless class_options.key?(name)
             defaults = if options[:type] == :boolean
-              { }
+              {}
             elsif [true, false].include?(default_value_for_option(name, options))
               { banner: "" }
             else
@@ -195,7 +200,7 @@ module Rails
       end
 
       # Make class option aware of Rails::Generators.options and Rails::Generators.aliases.
-      def self.class_option(name, options={}) #:nodoc:
+      def self.class_option(name, options = {}) #:nodoc:
         options[:desc]    = "Indicates when to generate #{name.to_s.humanize.downcase}" unless options.key?(:desc)
         options[:aliases] = default_aliases_for_option(name, options)
         options[:default] = default_value_for_option(name, options)
@@ -208,14 +213,14 @@ module Rails
       def self.default_source_root
         return unless base_name && generator_name
         return unless default_generator_root
-        path = File.join(default_generator_root, 'templates')
+        path = File.join(default_generator_root, "templates")
         path if File.exist?(path)
       end
 
       # Returns the base root for a common set of generators. This is used to dynamically
       # guess the default source root.
       def self.base_root
-        File.dirname(__FILE__)
+        __dir__
       end
 
       # Cache source root and add lib/generators/base/generator/templates to
@@ -230,7 +235,7 @@ module Rails
           Rails::Generators.subclasses << base
 
           Rails::Generators.templates_path.each do |path|
-            if base.name.include?('::')
+            if base.name.include?("::")
               base.source_paths << File.join(path, base.base_name, base.generator_name)
             else
               base.source_paths << File.join(path, base.generator_name)
@@ -239,11 +244,11 @@ module Rails
         end
       end
 
-      protected
+      private
 
         # Check whether the given class names are already taken by user
         # application or Ruby on Rails.
-        def class_collisions(*class_names) #:nodoc:
+        def class_collisions(*class_names)
           return unless behavior == :invoke
 
           class_names.flatten.each do |class_name|
@@ -251,35 +256,69 @@ module Rails
             next if class_name.strip.empty?
 
             # Split the class from its module nesting
-            nesting = class_name.split('::')
+            nesting = class_name.split("::")
             last_name = nesting.pop
             last = extract_last_module(nesting)
 
             if last && last.const_defined?(last_name.camelize, false)
-              raise Error, "The name '#{class_name}' is either already used in your application " <<
-                           "or reserved by Ruby on Rails. Please choose an alternative and run "  <<
+              raise Error, "The name '#{class_name}' is either already used in your application " \
+                           "or reserved by Ruby on Rails. Please choose an alternative and run "  \
                            "this generator again."
             end
           end
         end
 
         # Takes in an array of nested modules and extracts the last module
-        def extract_last_module(nesting)
+        def extract_last_module(nesting) # :doc:
           nesting.inject(Object) do |last_module, nest|
             break unless last_module.const_defined?(nest, false)
             last_module.const_get(nest)
           end
         end
 
+        # Wrap block with namespace of current application
+        # if namespace exists and is not skipped
+        def module_namespacing(&block) # :doc:
+          content = capture(&block)
+          content = wrap_with_namespace(content) if namespaced?
+          concat(content)
+        end
+
+        def indent(content, multiplier = 2) # :doc:
+          spaces = " " * multiplier
+          content.each_line.map { |line| line.blank? ? line : "#{spaces}#{line}" }.join
+        end
+
+        def wrap_with_namespace(content) # :doc:
+          content = indent(content).chomp
+          "module #{namespace.name}\n#{content}\nend\n"
+        end
+
+        def namespace # :doc:
+          Rails::Generators.namespace
+        end
+
+        def namespaced? # :doc:
+          !options[:skip_namespace] && namespace
+        end
+
+        def namespace_dirs
+          @namespace_dirs ||= namespace.name.split("::").map(&:underscore)
+        end
+
+        def namespaced_path # :doc:
+          @namespaced_path ||= namespace_dirs.join("/")
+        end
+
         # Use Rails default banner.
-        def self.banner
-          "rails generate #{namespace.sub(/^rails:/,'')} #{self.arguments.map(&:usage).join(' ')} [options]".gsub(/\s+/, ' ')
+        def self.banner # :doc:
+          "rails generate #{namespace.sub(/^rails:/, '')} #{arguments.map(&:usage).join(' ')} [options]".gsub(/\s+/, " ")
         end
 
         # Sets the base_name taking into account the current class namespace.
-        def self.base_name
+        def self.base_name # :doc:
           @base_name ||= begin
-            if base = name.to_s.split('::').first
+            if base = name.to_s.split("::").first
               base.underscore
             end
           end
@@ -287,10 +326,10 @@ module Rails
 
         # Removes the namespaces and get the generator name. For example,
         # Rails::Generators::ModelGenerator will return "model" as generator name.
-        def self.generator_name
+        def self.generator_name # :doc:
           @generator_name ||= begin
-            if generator = name.to_s.split('::').last
-              generator.sub!(/Generator$/, '')
+            if generator = name.to_s.split("::").last
+              generator.sub!(/Generator$/, "")
               generator.underscore
             end
           end
@@ -298,21 +337,21 @@ module Rails
 
         # Returns the default value for the option name given doing a lookup in
         # Rails::Generators.options.
-        def self.default_value_for_option(name, options)
+        def self.default_value_for_option(name, options) # :doc:
           default_for_option(Rails::Generators.options, name, options, options[:default])
         end
 
         # Returns default aliases for the option name given doing a lookup in
         # Rails::Generators.aliases.
-        def self.default_aliases_for_option(name, options)
+        def self.default_aliases_for_option(name, options) # :doc:
           default_for_option(Rails::Generators.aliases, name, options, options[:aliases])
         end
 
         # Returns default for the option name given doing a lookup in config.
-        def self.default_for_option(config, name, options, default)
-          if generator_name and c = config[generator_name.to_sym] and c.key?(name)
+        def self.default_for_option(config, name, options, default) # :doc:
+          if generator_name && (c = config[generator_name.to_sym]) && c.key?(name)
             c[name]
-          elsif base_name and c = config[base_name.to_sym] and c.key?(name)
+          elsif base_name && (c = config[base_name.to_sym]) && c.key?(name)
             c[name]
           elsif config[:rails].key?(name)
             config[:rails][name]
@@ -331,7 +370,7 @@ module Rails
         def self.prepare_for_invocation(name, value) #:nodoc:
           return super unless value.is_a?(String) || value.is_a?(Symbol)
 
-          if value && constants = self.hooks[name]
+          if value && constants = hooks[name]
             value = name if TrueClass === value
             Rails::Generators.find_by_namespace(value, *constants)
           elsif klass = Rails::Generators.find_by_namespace(value)
@@ -343,7 +382,7 @@ module Rails
 
         # Small macro to add ruby as an option to the generator with proper
         # default value plus an instance helper method called shebang.
-        def self.add_shebang_option!
+        def self.add_shebang_option! # :doc:
           class_option :ruby, type: :string, aliases: "-r", default: Thor::Util.ruby_command,
                               desc: "Path to the Ruby binary of your choice", banner: "PATH"
 
@@ -361,7 +400,7 @@ module Rails
           }
         end
 
-        def self.usage_path
+        def self.usage_path # :doc:
           paths = [
             source_root && File.expand_path("../USAGE", source_root),
             default_generator_root && File.join(default_generator_root, "USAGE")
@@ -369,11 +408,10 @@ module Rails
           paths.compact.detect { |path| File.exist? path }
         end
 
-        def self.default_generator_root
+        def self.default_generator_root # :doc:
           path = File.expand_path(File.join(base_name, generator_name), base_root)
           path if File.exist?(path)
         end
-
     end
   end
 end
diff --git a/railties/lib/rails/generators/css/assets/assets_generator.rb b/railties/lib/rails/generators/css/assets/assets_generator.rb
index e4a305f4b3..f657d1e50f 100644
--- a/railties/lib/rails/generators/css/assets/assets_generator.rb
+++ b/railties/lib/rails/generators/css/assets/assets_generator.rb
@@ -1,12 +1,14 @@
+# frozen_string_literal: true
+
 require "rails/generators/named_base"
 
 module Css # :nodoc:
   module Generators # :nodoc:
     class AssetsGenerator < Rails::Generators::NamedBase # :nodoc:
-      source_root File.expand_path("../templates", __FILE__)
+      source_root File.expand_path("templates", __dir__)
 
       def copy_stylesheet
-        copy_file "stylesheet.css", File.join('app/assets/stylesheets', class_path, "#{file_name}.css")
+        copy_file "stylesheet.css", File.join("app/assets/stylesheets", class_path, "#{file_name}.css")
       end
     end
   end
diff --git a/railties/lib/rails/generators/css/scaffold/scaffold_generator.rb b/railties/lib/rails/generators/css/scaffold/scaffold_generator.rb
index cf534030f9..89c560f382 100644
--- a/railties/lib/rails/generators/css/scaffold/scaffold_generator.rb
+++ b/railties/lib/rails/generators/css/scaffold/scaffold_generator.rb
@@ -1,15 +1,17 @@
+# frozen_string_literal: true
+
 require "rails/generators/named_base"
 
 module Css # :nodoc:
   module Generators # :nodoc:
     class ScaffoldGenerator < Rails::Generators::NamedBase # :nodoc:
+      source_root Rails::Generators::ScaffoldGenerator.source_root
+
       # In order to allow the Sass generators to pick up the default Rails CSS and
       # transform it, we leave it in a standard location for the CSS stylesheet
       # generators to handle. For the simple, default case, just copy it over.
       def copy_stylesheet
-        dir = Rails::Generators::ScaffoldGenerator.source_root
-        file = File.join(dir, "scaffold.css")
-        create_file "app/assets/stylesheets/scaffold.css", File.read(file)
+        copy_file "scaffold.css", "app/assets/stylesheets/scaffold.css"
       end
     end
   end
diff --git a/railties/lib/rails/generators/erb.rb b/railties/lib/rails/generators/erb.rb
index 0755ac335c..ba20bcd32a 100644
--- a/railties/lib/rails/generators/erb.rb
+++ b/railties/lib/rails/generators/erb.rb
@@ -1,25 +1,27 @@
-require 'rails/generators/named_base'
+# frozen_string_literal: true
+
+require "rails/generators/named_base"
 
 module Erb # :nodoc:
   module Generators # :nodoc:
     class Base < Rails::Generators::NamedBase #:nodoc:
-      protected
+      private
 
-      def formats
-        [format]
-      end
+        def formats
+          [format]
+        end
 
-      def format
-        :html
-      end
+        def format
+          :html
+        end
 
-      def handler
-        :erb
-      end
+        def handler
+          :erb
+        end
 
-      def filename_with_extensions(name, format = self.format)
-        [name, format, handler].compact.join(".")
-      end
+        def filename_with_extensions(name, file_format = format)
+          [name, file_format, handler].compact.join(".")
+        end
     end
   end
 end
diff --git a/railties/lib/rails/generators/erb/controller/controller_generator.rb b/railties/lib/rails/generators/erb/controller/controller_generator.rb
index 94c1b835d1..8e13744b2a 100644
--- a/railties/lib/rails/generators/erb/controller/controller_generator.rb
+++ b/railties/lib/rails/generators/erb/controller/controller_generator.rb
@@ -1,4 +1,6 @@
-require 'rails/generators/erb'
+# frozen_string_literal: true
+
+require "rails/generators/erb"
 
 module Erb # :nodoc:
   module Generators # :nodoc:
diff --git a/railties/lib/rails/generators/erb/controller/templates/view.html.erb b/railties/lib/rails/generators/erb/controller/templates/view.html.erb.tt
index cd54d13d83..cd54d13d83 100644
--- a/railties/lib/rails/generators/erb/controller/templates/view.html.erb
+++ b/railties/lib/rails/generators/erb/controller/templates/view.html.erb.tt
diff --git a/railties/lib/rails/generators/erb/mailer/mailer_generator.rb b/railties/lib/rails/generators/erb/mailer/mailer_generator.rb
index 97f3657070..e2ea66415f 100644
--- a/railties/lib/rails/generators/erb/mailer/mailer_generator.rb
+++ b/railties/lib/rails/generators/erb/mailer/mailer_generator.rb
@@ -1,4 +1,6 @@
-require 'rails/generators/erb'
+# frozen_string_literal: true
+
+require "rails/generators/erb"
 
 module Erb # :nodoc:
   module Generators # :nodoc:
@@ -6,13 +8,13 @@ module Erb # :nodoc:
       argument :actions, type: :array, default: [], banner: "method method"
 
       def copy_view_files
-        view_base_path = File.join("app/views", class_path, file_name + '_mailer')
+        view_base_path = File.join("app/views", class_path, file_name + "_mailer")
         empty_directory view_base_path
 
-        if self.behavior == :invoke
+        if behavior == :invoke
           formats.each do |format|
-            layout_path = File.join('app/views/layouts', class_path, filename_with_extensions('mailer', format))
-            template filename_with_extensions(:layout, format), layout_path
+            layout_path = File.join("app/views/layouts", class_path, filename_with_extensions("mailer", format))
+            template filename_with_extensions(:layout, format), layout_path unless File.exist?(layout_path)
           end
         end
 
@@ -26,15 +28,15 @@ module Erb # :nodoc:
         end
       end
 
-      protected
+      private
 
-      def formats
-        [:text, :html]
-      end
+        def formats
+          [:text, :html]
+        end
 
-      def file_name
-        @_file_name ||= super.gsub(/_mailer/i, '')
-      end
+        def file_name
+          @_file_name ||= super.gsub(/_mailer/i, "")
+        end
     end
   end
 end
diff --git a/railties/lib/rails/generators/erb/mailer/templates/view.html.erb b/railties/lib/rails/generators/erb/mailer/templates/view.html.erb.tt
index b5045671b3..b5045671b3 100644
--- a/railties/lib/rails/generators/erb/mailer/templates/view.html.erb
+++ b/railties/lib/rails/generators/erb/mailer/templates/view.html.erb.tt
diff --git a/railties/lib/rails/generators/erb/mailer/templates/view.text.erb b/railties/lib/rails/generators/erb/mailer/templates/view.text.erb.tt
index 342285df19..342285df19 100644
--- a/railties/lib/rails/generators/erb/mailer/templates/view.text.erb
+++ b/railties/lib/rails/generators/erb/mailer/templates/view.text.erb.tt
diff --git a/railties/lib/rails/generators/erb/scaffold/scaffold_generator.rb b/railties/lib/rails/generators/erb/scaffold/scaffold_generator.rb
index c94829a0ae..2fc04e4094 100644
--- a/railties/lib/rails/generators/erb/scaffold/scaffold_generator.rb
+++ b/railties/lib/rails/generators/erb/scaffold/scaffold_generator.rb
@@ -1,5 +1,7 @@
-require 'rails/generators/erb'
-require 'rails/generators/resource_helpers'
+# frozen_string_literal: true
+
+require "rails/generators/erb"
+require "rails/generators/resource_helpers"
 
 module Erb # :nodoc:
   module Generators # :nodoc:
@@ -21,7 +23,7 @@ module Erb # :nodoc:
         end
       end
 
-    protected
+    private
 
       def available_views
         %w(index edit show new _form)
diff --git a/railties/lib/rails/generators/erb/scaffold/templates/_form.html.erb b/railties/lib/rails/generators/erb/scaffold/templates/_form.html.erb.tt
index 519b6c8603..518cb1121e 100644
--- a/railties/lib/rails/generators/erb/scaffold/templates/_form.html.erb
+++ b/railties/lib/rails/generators/erb/scaffold/templates/_form.html.erb.tt
@@ -1,4 +1,4 @@
-<%%= form_for(<%= singular_table_name %>) do |f| %>
+<%%= form_with(model: <%= model_resource_name %>, local: true) do |form| %>
   <%% if <%= singular_table_name %>.errors.any? %>
     <div id="error_explanation">
       <h2><%%= pluralize(<%= singular_table_name %>.errors.count, "error") %> prohibited this <%= singular_table_name %> from being saved:</h2>
@@ -14,21 +14,21 @@
 <% attributes.each do |attribute| -%>
   <div class="field">
 <% if attribute.password_digest? -%>
-    <%%= f.label :password %>
-    <%%= f.password_field :password %>
+    <%%= form.label :password %>
+    <%%= form.password_field :password %>
   </div>
 
   <div class="field">
-    <%%= f.label :password_confirmation %>
-    <%%= f.password_field :password_confirmation %>
+    <%%= form.label :password_confirmation %>
+    <%%= form.password_field :password_confirmation %>
 <% else -%>
-    <%%= f.label :<%= attribute.column_name %> %>
-    <%%= f.<%= attribute.field_type %> :<%= attribute.column_name %> %>
+    <%%= form.label :<%= attribute.column_name %> %>
+    <%%= form.<%= attribute.field_type %> :<%= attribute.column_name %> %>
 <% end -%>
   </div>
 
 <% end -%>
   <div class="actions">
-    <%%= f.submit %>
+    <%%= form.submit %>
   </div>
 <%% end %>
diff --git a/railties/lib/rails/generators/erb/scaffold/templates/edit.html.erb b/railties/lib/rails/generators/erb/scaffold/templates/edit.html.erb.tt
index 81329473d9..81329473d9 100644
--- a/railties/lib/rails/generators/erb/scaffold/templates/edit.html.erb
+++ b/railties/lib/rails/generators/erb/scaffold/templates/edit.html.erb.tt
diff --git a/railties/lib/rails/generators/erb/scaffold/templates/index.html.erb b/railties/lib/rails/generators/erb/scaffold/templates/index.html.erb.tt
index 5f4904fee1..e1ede7c713 100644
--- a/railties/lib/rails/generators/erb/scaffold/templates/index.html.erb
+++ b/railties/lib/rails/generators/erb/scaffold/templates/index.html.erb.tt
@@ -18,9 +18,9 @@
 <% attributes.reject(&:password_digest?).each do |attribute| -%>
         <td><%%= <%= singular_table_name %>.<%= attribute.name %> %></td>
 <% end -%>
-        <td><%%= link_to 'Show', <%= singular_table_name %> %></td>
-        <td><%%= link_to 'Edit', edit_<%= singular_table_name %>_path(<%= singular_table_name %>) %></td>
-        <td><%%= link_to 'Destroy', <%= singular_table_name %>, method: :delete, data: { confirm: 'Are you sure?' } %></td>
+        <td><%%= link_to 'Show', <%= model_resource_name %> %></td>
+        <td><%%= link_to 'Edit', edit_<%= singular_route_name %>_path(<%= singular_table_name %>) %></td>
+        <td><%%= link_to 'Destroy', <%= model_resource_name %>, method: :delete, data: { confirm: 'Are you sure?' } %></td>
       </tr>
     <%% end %>
   </tbody>
@@ -28,4 +28,4 @@
 
 <br>
 
-<%%= link_to 'New <%= singular_table_name.titleize %>', new_<%= singular_table_name %>_path %>
+<%%= link_to 'New <%= singular_table_name.titleize %>', new_<%= singular_route_name %>_path %>
diff --git a/railties/lib/rails/generators/erb/scaffold/templates/new.html.erb b/railties/lib/rails/generators/erb/scaffold/templates/new.html.erb.tt
index 9b2b2f4875..9b2b2f4875 100644
--- a/railties/lib/rails/generators/erb/scaffold/templates/new.html.erb
+++ b/railties/lib/rails/generators/erb/scaffold/templates/new.html.erb.tt
diff --git a/railties/lib/rails/generators/erb/scaffold/templates/show.html.erb b/railties/lib/rails/generators/erb/scaffold/templates/show.html.erb.tt
index 5e634153be..5e634153be 100644
--- a/railties/lib/rails/generators/erb/scaffold/templates/show.html.erb
+++ b/railties/lib/rails/generators/erb/scaffold/templates/show.html.erb.tt
diff --git a/railties/lib/rails/generators/generated_attribute.rb b/railties/lib/rails/generators/generated_attribute.rb
index 7e437e7344..2728459968 100644
--- a/railties/lib/rails/generators/generated_attribute.rb
+++ b/railties/lib/rails/generators/generated_attribute.rb
@@ -1,4 +1,6 @@
-require 'active_support/time'
+# frozen_string_literal: true
+
+require "active_support/time"
 
 module Rails
   module Generators
@@ -12,7 +14,7 @@ module Rails
 
       class << self
         def parse(column_definition)
-          name, type, has_index = column_definition.split(':')
+          name, type, has_index = column_definition.split(":")
 
           # if user provided "name:index" instead of "name:string:index"
           # type should be set blank so GeneratedAttribute's constructor
@@ -56,7 +58,7 @@ module Rails
         end
       end
 
-      def initialize(name, type=nil, index_type=false, attr_options={})
+      def initialize(name, type = nil, index_type = false, attr_options = {})
         @name           = name
         @type           = type || :string
         @has_index      = INDEX_OPTIONS.include?(index_type)
@@ -66,40 +68,40 @@ module Rails
 
       def field_type
         @field_type ||= case type
-          when :integer              then :number_field
-          when :float, :decimal      then :text_field
-          when :time                 then :time_select
-          when :datetime, :timestamp then :datetime_select
-          when :date                 then :date_select
-          when :text                 then :text_area
-          when :boolean              then :check_box
+                        when :integer              then :number_field
+                        when :float, :decimal      then :text_field
+                        when :time                 then :time_select
+                        when :datetime, :timestamp then :datetime_select
+                        when :date                 then :date_select
+                        when :text                 then :text_area
+                        when :boolean              then :check_box
           else
-            :text_field
+                          :text_field
         end
       end
 
       def default
         @default ||= case type
-          when :integer                     then 1
-          when :float                       then 1.5
-          when :decimal                     then "9.99"
-          when :datetime, :timestamp, :time then Time.now.to_s(:db)
-          when :date                        then Date.today.to_s(:db)
-          when :string                      then name == "type" ? "" : "MyString"
-          when :text                        then "MyText"
-          when :boolean                     then false
-          when :references, :belongs_to     then nil
+                     when :integer                     then 1
+                     when :float                       then 1.5
+                     when :decimal                     then "9.99"
+                     when :datetime, :timestamp, :time then Time.now.to_s(:db)
+                     when :date                        then Date.today.to_s(:db)
+                     when :string                      then name == "type" ? "" : "MyString"
+                     when :text                        then "MyText"
+                     when :boolean                     then false
+                     when :references, :belongs_to     then nil
           else
-            ""
+                       ""
         end
       end
 
       def plural_name
-        name.sub(/_id$/, '').pluralize
+        name.sub(/_id$/, "").pluralize
       end
 
       def singular_name
-        name.sub(/_id$/, '').singularize
+        name.sub(/_id$/, "").singularize
       end
 
       def human_name
@@ -127,11 +129,11 @@ module Rails
       end
 
       def polymorphic?
-        self.attr_options[:polymorphic]
+        attr_options[:polymorphic]
       end
 
       def required?
-        self.attr_options[:required]
+        attr_options[:required]
       end
 
       def has_index?
@@ -143,7 +145,7 @@ module Rails
       end
 
       def password_digest?
-        name == 'password' && type == :digest
+        name == "password" && type == :digest
       end
 
       def token?
@@ -151,7 +153,7 @@ module Rails
       end
 
       def inject_options
-        "".tap { |s| options_for_migration.each { |k,v| s << ", #{k}: #{v.inspect}" } }
+        "".dup.tap { |s| options_for_migration.each { |k, v| s << ", #{k}: #{v.inspect}" } }
       end
 
       def inject_index_options
diff --git a/railties/lib/rails/generators/js/assets/assets_generator.rb b/railties/lib/rails/generators/js/assets/assets_generator.rb
index 1e925b2cd2..9d32c666dc 100644
--- a/railties/lib/rails/generators/js/assets/assets_generator.rb
+++ b/railties/lib/rails/generators/js/assets/assets_generator.rb
@@ -1,12 +1,14 @@
+# frozen_string_literal: true
+
 require "rails/generators/named_base"
 
 module Js # :nodoc:
   module Generators # :nodoc:
     class AssetsGenerator < Rails::Generators::NamedBase # :nodoc:
-      source_root File.expand_path("../templates", __FILE__)
+      source_root File.expand_path("templates", __dir__)
 
       def copy_javascript
-        copy_file "javascript.js", File.join('app/assets/javascripts', class_path, "#{file_name}.js")
+        copy_file "javascript.js", File.join("app/assets/javascripts", class_path, "#{file_name}.js")
       end
     end
   end
diff --git a/railties/lib/rails/generators/migration.rb b/railties/lib/rails/generators/migration.rb
index 87f2e1d42b..1cbccfe461 100644
--- a/railties/lib/rails/generators/migration.rb
+++ b/railties/lib/rails/generators/migration.rb
@@ -1,5 +1,7 @@
-require 'active_support/concern'
-require 'rails/generators/actions/create_migration'
+# frozen_string_literal: true
+
+require "active_support/concern"
+require "rails/generators/actions/create_migration"
 
 module Rails
   module Generators
@@ -35,11 +37,11 @@ module Rails
       end
 
       def set_migration_assigns!(destination)
-        destination = File.expand_path(destination, self.destination_root)
+        destination = File.expand_path(destination, destination_root)
 
         migration_dir = File.dirname(destination)
         @migration_number     = self.class.next_migration_number(migration_dir)
-        @migration_file_name  = File.basename(destination, '.rb')
+        @migration_file_name  = File.basename(destination, ".rb")
         @migration_class_name = @migration_file_name.camelize
       end
 
@@ -52,16 +54,16 @@ module Rails
       #
       #   migration_template "migration.rb", "db/migrate/add_foo_to_bar.rb"
       def migration_template(source, destination, config = {})
-        source  = File.expand_path(find_in_source_paths(source.to_s))
+        source = File.expand_path(find_in_source_paths(source.to_s))
 
         set_migration_assigns!(destination)
-        context = instance_eval('binding')
+        context = instance_eval("binding")
 
         dir, base = File.split(destination)
-        numbered_destination = File.join(dir, ["%migration_number%", base].join('_'))
+        numbered_destination = File.join(dir, ["%migration_number%", base].join("_"))
 
         create_migration numbered_destination, nil, config do
-          ERB.new(::File.binread(source), nil, '-', '@output_buffer').result(context)
+          ERB.new(::File.binread(source), nil, "-", "@output_buffer").result(context)
         end
       end
     end
diff --git a/railties/lib/rails/generators/model_helpers.rb b/railties/lib/rails/generators/model_helpers.rb
index 42c646543e..50078404b3 100644
--- a/railties/lib/rails/generators/model_helpers.rb
+++ b/railties/lib/rails/generators/model_helpers.rb
@@ -1,4 +1,6 @@
-require 'rails/generators/active_model'
+# frozen_string_literal: true
+
+require "rails/generators/active_model"
 
 module Rails
   module Generators
@@ -8,7 +10,7 @@ module Rails
       mattr_accessor :skip_warn
 
       def self.included(base) #:nodoc:
-        base.class_option :force_plural, type: :boolean, default: false, desc: 'Forces the use of the given model name'
+        base.class_option :force_plural, type: :boolean, default: false, desc: "Forces the use of the given model name"
       end
 
       def initialize(args, *_options)
diff --git a/railties/lib/rails/generators/named_base.rb b/railties/lib/rails/generators/named_base.rb
index ee076eb711..98fcc95964 100644
--- a/railties/lib/rails/generators/named_base.rb
+++ b/railties/lib/rails/generators/named_base.rb
@@ -1,20 +1,19 @@
-require 'active_support/core_ext/module/introspection'
-require 'rails/generators/base'
-require 'rails/generators/generated_attribute'
+# frozen_string_literal: true
+
+require "rails/generators/base"
+require "rails/generators/generated_attribute"
 
 module Rails
   module Generators
     class NamedBase < Base
       argument :name, type: :string
-      class_option :skip_namespace, type: :boolean, default: false,
-                                    desc: "Skip namespace (affects only isolated applications)"
 
       def initialize(args, *options) #:nodoc:
         @inside_template = nil
         # Unfreeze name in case it's given as a frozen string
         args[0] = args[0].dup if args[0].is_a?(String) && args[0].frozen?
         super
-        assign_names!(self.name)
+        assign_names!(name)
         parse_attributes! if respond_to?(:attributes)
       end
 
@@ -28,182 +27,181 @@ module Rails
         end
 
         def js_template(source, destination)
-          template(source + '.js', destination + '.js')
+          template(source + ".js", destination + ".js")
         end
       end
 
+      # TODO Change this to private once we've dropped Ruby 2.2 support.
+      # Workaround for Ruby 2.2 "private attribute?" warning.
       protected
         attr_reader :file_name
 
+      private
+
         # FIXME: We are avoiding to use alias because a bug on thor that make
         # this method public and add it to the task list.
-        def singular_name
+        def singular_name # :doc:
           file_name
         end
 
-        # Wrap block with namespace of current application
-        # if namespace exists and is not skipped
-        def module_namespacing(&block)
-          content = capture(&block)
-          content = wrap_with_namespace(content) if namespaced?
-          concat(content)
-        end
-
-        def indent(content, multiplier = 2)
-          spaces = " " * multiplier
-          content.each_line.map {|line| line.blank? ? line : "#{spaces}#{line}" }.join
-        end
-
-        def wrap_with_namespace(content)
-          content = indent(content).chomp
-          "module #{namespace.name}\n#{content}\nend\n"
-        end
-
-        def inside_template
+        def inside_template # :doc:
           @inside_template = true
           yield
         ensure
           @inside_template = false
         end
 
-        def inside_template?
+        def inside_template? # :doc:
           @inside_template
         end
 
-        def namespace
-          Rails::Generators.namespace
+        def file_path # :doc:
+          @file_path ||= (class_path + [file_name]).join("/")
         end
 
-        def namespaced?
-          !options[:skip_namespace] && namespace
-        end
-
-        def file_path
-          @file_path ||= (class_path + [file_name]).join('/')
-        end
-
-        def class_path
+        def class_path # :doc:
           inside_template? || !namespaced? ? regular_class_path : namespaced_class_path
         end
 
-        def regular_class_path
+        def regular_class_path # :doc:
           @class_path
         end
 
-        def namespaced_file_path
-          @namespaced_file_path ||= namespaced_class_path.join("/")
-        end
-
-        def namespaced_class_path
-          @namespaced_class_path ||= [namespaced_path] + @class_path
-        end
-
-        def namespaced_path
-          @namespaced_path ||= namespace.name.split("::").first.underscore
+        def namespaced_class_path # :doc:
+          @namespaced_class_path ||= namespace_dirs + @class_path
         end
 
-        def class_name
-          (class_path + [file_name]).map!(&:camelize).join('::')
+        def class_name # :doc:
+          (class_path + [file_name]).map!(&:camelize).join("::")
         end
 
-        def human_name
+        def human_name # :doc:
           @human_name ||= singular_name.humanize
         end
 
-        def plural_name
+        def plural_name # :doc:
           @plural_name ||= singular_name.pluralize
         end
 
-        def i18n_scope
-          @i18n_scope ||= file_path.tr('/', '.')
+        def i18n_scope # :doc:
+          @i18n_scope ||= file_path.tr("/", ".")
         end
 
-        def table_name
+        def table_name # :doc:
           @table_name ||= begin
             base = pluralize_table_names? ? plural_name : singular_name
-            (class_path + [base]).join('_')
+            (class_path + [base]).join("_")
           end
         end
 
-        def uncountable?
+        def uncountable? # :doc:
           singular_name == plural_name
         end
 
-        def index_helper
-          uncountable? ? "#{plural_table_name}_index" : plural_table_name
+        def index_helper # :doc:
+          uncountable? ? "#{plural_route_name}_index" : plural_route_name
         end
 
-        def show_helper
-          "#{singular_table_name}_url(@#{singular_table_name})"
+        def show_helper # :doc:
+          "#{singular_route_name}_url(@#{singular_table_name})"
         end
 
-        def edit_helper
+        def edit_helper # :doc:
           "edit_#{show_helper}"
         end
 
-        def new_helper
-          "new_#{singular_table_name}_url"
+        def new_helper # :doc:
+          "new_#{singular_route_name}_url"
         end
 
-        def singular_table_name
+        def singular_table_name # :doc:
           @singular_table_name ||= (pluralize_table_names? ? table_name.singularize : table_name)
         end
 
-        def plural_table_name
+        def plural_table_name # :doc:
           @plural_table_name ||= (pluralize_table_names? ? table_name : table_name.pluralize)
         end
 
-        def plural_file_name
+        def plural_file_name # :doc:
           @plural_file_name ||= file_name.pluralize
         end
 
-        def fixture_file_name
+        def fixture_file_name # :doc:
           @fixture_file_name ||= (pluralize_table_names? ? plural_file_name : file_name)
         end
 
-        def route_url
-          @route_url ||= class_path.collect {|dname| "/" + dname }.join + "/" + plural_file_name
+        def route_url # :doc:
+          @route_url ||= class_path.collect { |dname| "/" + dname }.join + "/" + plural_file_name
         end
 
-        def url_helper_prefix
-          @url_helper_prefix ||= (class_path + [file_name]).join('_')
+        def url_helper_prefix # :doc:
+          @url_helper_prefix ||= (class_path + [file_name]).join("_")
         end
 
         # Tries to retrieve the application name or simply return application.
-        def application_name
+        def application_name # :doc:
           if defined?(Rails) && Rails.application
-            Rails.application.class.name.split('::').first.underscore
+            Rails.application.class.name.split("::").first.underscore
           else
             "application"
           end
         end
 
-        def assign_names!(name) #:nodoc:
-          @class_path = name.include?('/') ? name.split('/') : name.split('::')
+        def redirect_resource_name # :doc:
+          model_resource_name(prefix: "@")
+        end
+
+        def model_resource_name(prefix: "") # :doc:
+          resource_name = "#{prefix}#{singular_table_name}"
+          if options[:model_name]
+            "[#{controller_class_path.map { |name| ":" + name }.join(", ")}, #{resource_name}]"
+          else
+            resource_name
+          end
+        end
+
+        def singular_route_name # :doc:
+          if options[:model_name]
+            "#{controller_class_path.join('_')}_#{singular_table_name}"
+          else
+            singular_table_name
+          end
+        end
+
+        def plural_route_name # :doc:
+          if options[:model_name]
+            "#{controller_class_path.join('_')}_#{plural_table_name}"
+          else
+            plural_table_name
+          end
+        end
+
+        def assign_names!(name)
+          @class_path = name.include?("/") ? name.split("/") : name.split("::")
           @class_path.map!(&:underscore)
           @file_name = @class_path.pop
         end
 
         # Convert attributes array into GeneratedAttribute objects.
-        def parse_attributes! #:nodoc:
+        def parse_attributes!
           self.attributes = (attributes || []).map do |attr|
             Rails::Generators::GeneratedAttribute.parse(attr)
           end
         end
 
-        def attributes_names
+        def attributes_names # :doc:
           @attributes_names ||= attributes.each_with_object([]) do |a, names|
             names << a.column_name
-            names << 'password_confirmation' if a.password_digest?
+            names << "password_confirmation" if a.password_digest?
             names << "#{a.name}_type" if a.polymorphic?
           end
         end
 
-        def pluralize_table_names?
+        def pluralize_table_names? # :doc:
           !defined?(ActiveRecord::Base) || ActiveRecord::Base.pluralize_table_names
         end
 
-        def mountable_engine?
+        def mountable_engine? # :doc:
           defined?(ENGINE_ROOT) && namespaced?
         end
 
@@ -217,9 +215,9 @@ module Rails
         # If the generator is invoked with class name Admin, it will check for
         # the presence of "AdminDecorator".
         #
-        def self.check_class_collision(options={})
+        def self.check_class_collision(options = {}) # :doc:
           define_method :check_class_collision do
-            name = if self.respond_to?(:controller_class_name) # for ScaffoldBase
+            name = if respond_to?(:controller_class_name) # for ResourceHelpers
               controller_class_name
             else
               class_name
diff --git a/railties/lib/rails/generators/rails/app/app_generator.rb b/railties/lib/rails/generators/rails/app/app_generator.rb
index 448dce06af..bf4570db90 100644
--- a/railties/lib/rails/generators/rails/app/app_generator.rb
+++ b/railties/lib/rails/generators/rails/app/app_generator.rb
@@ -1,4 +1,6 @@
-require 'rails/generators/app_base'
+# frozen_string_literal: true
+
+require "rails/generators/app_base"
 
 module Rails
   module ActionMethods # :nodoc:
@@ -32,6 +34,14 @@ module Rails
   # This allows you to override entire operations, like the creation of the
   # Gemfile, README, or JavaScript files, without needing to know exactly
   # what those operations do so you can create another template action.
+  #
+  #  class CustomAppBuilder < Rails::AppBuilder
+  #    def test
+  #      @generator.gem "rspec-rails", group: [:development, :test]
+  #      run "bundle install"
+  #      generate "rspec:install"
+  #    end
+  #  end
   class AppBuilder
     def rakefile
       template "Rakefile"
@@ -41,6 +51,10 @@ module Rails
       copy_file "README.md", "README.md"
     end
 
+    def ruby_version
+      template "ruby-version", ".ruby-version"
+    end
+
     def gemfile
       template "Gemfile"
     end
@@ -53,14 +67,24 @@ module Rails
       template "gitignore", ".gitignore"
     end
 
+    def version_control
+      if !options[:skip_git] && !options[:pretend]
+        run "git init", capture: options[:quiet]
+      end
+    end
+
+    def package_json
+      template "package.json"
+    end
+
     def app
-      directory 'app'
+      directory "app"
 
-      keep_file  'app/assets/images'
-      empty_directory_with_keep_file 'app/assets/javascripts/channels' unless options[:skip_action_cable]
+      keep_file "app/assets/images"
+      empty_directory_with_keep_file "app/assets/javascripts/channels" unless options[:skip_action_cable]
 
-      keep_file  'app/controllers/concerns'
-      keep_file  'app/models/concerns'
+      keep_file  "app/controllers/concerns"
+      keep_file  "app/models/concerns"
     end
 
     def bin
@@ -70,6 +94,16 @@ module Rails
       chmod "bin", 0755 & ~File.umask, verbose: false
     end
 
+    def bin_when_updating
+      bin_yarn_exist = File.exist?("bin/yarn")
+
+      bin
+
+      if options[:api] && !bin_yarn_exist
+        remove_file "bin/yarn"
+      end
+    end
+
     def config
       empty_directory "config"
 
@@ -77,10 +111,10 @@ module Rails
         template "routes.rb"
         template "application.rb"
         template "environment.rb"
-        template "secrets.yml"
         template "cable.yml" unless options[:skip_action_cable]
         template "puma.rb"   unless options[:skip_puma]
         template "spring.rb" if spring_install?
+        template "storage.yml" unless skip_active_storage?
 
         directory "environments"
         directory "initializers"
@@ -89,25 +123,60 @@ module Rails
     end
 
     def config_when_updating
-      cookie_serializer_config_exist = File.exist?('config/initializers/cookies_serializer.rb')
-      action_cable_config_exist = File.exist?('config/cable.yml')
-      rack_cors_config_exist = File.exist?('config/initializers/cors.rb')
+      cookie_serializer_config_exist = File.exist?("config/initializers/cookies_serializer.rb")
+      action_cable_config_exist      = File.exist?("config/cable.yml")
+      active_storage_config_exist    = File.exist?("config/storage.yml")
+      rack_cors_config_exist         = File.exist?("config/initializers/cors.rb")
+      assets_config_exist            = File.exist?("config/initializers/assets.rb")
+      csp_config_exist               = File.exist?("config/initializers/content_security_policy.rb")
 
       config
 
-      gsub_file 'config/environments/development.rb', /^(\s+)config\.file_watcher/, '\1# config.file_watcher'
-
       unless cookie_serializer_config_exist
-        gsub_file 'config/initializers/cookies_serializer.rb', /json(?!,)/, 'marshal'
+        gsub_file "config/initializers/cookies_serializer.rb", /json(?!,)/, "marshal"
       end
 
-      unless action_cable_config_exist
-        template 'config/cable.yml'
+      if !options[:skip_action_cable] && !action_cable_config_exist
+        template "config/cable.yml"
+      end
+
+      if !skip_active_storage? && !active_storage_config_exist
+        template "config/storage.yml"
       end
 
       unless rack_cors_config_exist
-        remove_file 'config/initializers/cors.rb'
+        remove_file "config/initializers/cors.rb"
       end
+
+      if options[:api]
+        unless cookie_serializer_config_exist
+          remove_file "config/initializers/cookies_serializer.rb"
+        end
+
+        unless assets_config_exist
+          remove_file "config/initializers/assets.rb"
+        end
+
+        unless csp_config_exist
+          remove_file "config/initializers/content_security_policy.rb"
+        end
+      end
+    end
+
+    def master_key
+      return if options[:pretend] || options[:dummy_app]
+
+      require "rails/generators/rails/master_key/master_key_generator"
+      master_key_generator = Rails::Generators::MasterKeyGenerator.new([], quiet: options[:quiet])
+      master_key_generator.add_master_key_file_silently
+      master_key_generator.ignore_master_key_file_silently
+    end
+
+    def credentials
+      return if options[:pretend] || options[:dummy_app]
+
+      require "rails/generators/rails/credentials/credentials_generator"
+      Rails::Generators::CredentialsGenerator.new([], quiet: options[:quiet]).add_credentials_file_silently
     end
 
     def database_yml
@@ -119,29 +188,40 @@ module Rails
     end
 
     def lib
-      empty_directory 'lib'
-      empty_directory_with_keep_file 'lib/tasks'
-      empty_directory_with_keep_file 'lib/assets'
+      empty_directory "lib"
+      empty_directory_with_keep_file "lib/tasks"
+      empty_directory_with_keep_file "lib/assets"
     end
 
     def log
-      empty_directory_with_keep_file 'log'
+      empty_directory_with_keep_file "log"
     end
 
     def public_directory
       directory "public", "public", recursive: false
     end
 
+    def storage
+      empty_directory_with_keep_file "storage"
+      empty_directory_with_keep_file "tmp/storage"
+    end
+
     def test
-      empty_directory_with_keep_file 'test/fixtures'
-      empty_directory_with_keep_file 'test/fixtures/files'
-      empty_directory_with_keep_file 'test/controllers'
-      empty_directory_with_keep_file 'test/mailers'
-      empty_directory_with_keep_file 'test/models'
-      empty_directory_with_keep_file 'test/helpers'
-      empty_directory_with_keep_file 'test/integration'
-
-      template 'test/test_helper.rb'
+      empty_directory_with_keep_file "test/fixtures"
+      empty_directory_with_keep_file "test/fixtures/files"
+      empty_directory_with_keep_file "test/controllers"
+      empty_directory_with_keep_file "test/mailers"
+      empty_directory_with_keep_file "test/models"
+      empty_directory_with_keep_file "test/helpers"
+      empty_directory_with_keep_file "test/integration"
+
+      template "test/test_helper.rb"
+    end
+
+    def system_test
+      empty_directory_with_keep_file "test/system"
+
+      template "test/application_system_test_case.rb"
     end
 
     def tmp
@@ -151,28 +231,19 @@ module Rails
     end
 
     def vendor
-      vendor_javascripts
-      vendor_stylesheets
-    end
-
-    def vendor_javascripts
-      unless options[:skip_javascript]
-        empty_directory_with_keep_file 'vendor/assets/javascripts'
-      end
-    end
-
-    def vendor_stylesheets
-      empty_directory_with_keep_file 'vendor/assets/stylesheets'
+      empty_directory_with_keep_file "vendor"
     end
   end
 
   module Generators
     # We need to store the RAILS_DEV_PATH in a constant, otherwise the path
     # can change in Ruby 1.8.7 when we FileUtils.cd.
-    RAILS_DEV_PATH = File.expand_path("../../../../../..", File.dirname(__FILE__))
+    RAILS_DEV_PATH = File.expand_path("../../../../../..", __dir__)
     RESERVED_NAMES = %w[application destroy plugin runner test]
 
     class AppGenerator < AppBase # :nodoc:
+      WEBPACKS = %w( react vue angular elm )
+
       add_shared_options_for "application"
 
       # Add bin/rails options
@@ -182,20 +253,24 @@ module Rails
       class_option :api, type: :boolean,
                          desc: "Preconfigure smaller stack for API only apps"
 
+      class_option :skip_bundle, type: :boolean, aliases: "-B", default: false,
+                                 desc: "Don't run bundle install"
+
+      class_option :webpack, type: :string, default: nil,
+                             desc: "Preconfigure for app-like JavaScript with Webpack (options: #{WEBPACKS.join('/')})"
+
       def initialize(*args)
         super
 
-        unless app_path
-          raise Error, "Application name should be provided in arguments. For details run: rails --help"
-        end
-
         if !options[:skip_active_record] && !DATABASES.include?(options[:database])
           raise Error, "Invalid value for --database option. Supported for preconfiguration are: #{DATABASES.join(", ")}."
         end
 
-        # Force sprockets to be skipped when generating API only apps.
+        # Force sprockets and yarn to be skipped when generating API only apps.
         # Can't modify options hash as it's frozen by default.
-        self.options = options.merge(skip_sprockets: true, skip_javascript: true).freeze if options[:api]
+        if options[:api]
+          self.options = options.merge(skip_sprockets: true, skip_javascript: true, skip_yarn: true).freeze
+        end
       end
 
       public_task :set_default_accessors!
@@ -204,9 +279,12 @@ module Rails
       def create_root_files
         build(:readme)
         build(:rakefile)
+        build(:ruby_version)
         build(:configru)
-        build(:gitignore) unless options[:skip_git]
-        build(:gemfile)   unless options[:skip_gemfile]
+        build(:gitignore)   unless options[:skip_git]
+        build(:gemfile)     unless options[:skip_gemfile]
+        build(:version_control)
+        build(:package_json) unless options[:skip_yarn]
       end
 
       def create_app_files
@@ -217,6 +295,11 @@ module Rails
         build(:bin)
       end
 
+      def update_bin_files
+        build(:bin_when_updating)
+      end
+      remove_task :update_bin_files
+
       def create_config_files
         build(:config)
       end
@@ -226,6 +309,19 @@ module Rails
       end
       remove_task :update_config_files
 
+      def create_master_key
+        build(:master_key)
+      end
+
+      def create_credentials
+        build(:credentials)
+      end
+
+      def display_upgrade_guide_info
+        say "\nAfter this, check Rails upgrade guide at http://guides.rubyonrails.org/upgrading_ruby_on_rails.html for more details about upgrading your app."
+      end
+      remove_task :display_upgrade_guide_info
+
       def create_boot_file
         template "config/boot.rb"
       end
@@ -236,6 +332,7 @@ module Rails
       end
 
       def create_db_files
+        return if options[:skip_active_record]
         build(:db)
       end
 
@@ -251,10 +348,6 @@ module Rails
         build(:public_directory)
       end
 
-      def create_test_files
-        build(:test) unless options[:skip_test]
-      end
-
       def create_tmp_files
         build(:tmp)
       end
@@ -263,110 +356,132 @@ module Rails
         build(:vendor)
       end
 
+      def create_test_files
+        build(:test) unless options[:skip_test]
+      end
+
+      def create_system_test_files
+        build(:system_test) if depends_on_system_test?
+      end
+
+      def create_storage_files
+        build(:storage) unless skip_active_storage?
+      end
+
       def delete_app_assets_if_api_option
         if options[:api]
-          remove_dir 'app/assets'
-          remove_dir 'lib/assets'
-          remove_dir 'tmp/cache/assets'
-          remove_dir 'vendor/assets'
+          remove_dir "app/assets"
+          remove_dir "lib/assets"
+          remove_dir "tmp/cache/assets"
         end
       end
 
       def delete_app_helpers_if_api_option
         if options[:api]
-          remove_dir 'app/helpers'
-          remove_dir 'test/helpers'
+          remove_dir "app/helpers"
+          remove_dir "test/helpers"
         end
       end
 
       def delete_application_layout_file_if_api_option
         if options[:api]
-          remove_file 'app/views/layouts/application.html.erb'
+          remove_file "app/views/layouts/application.html.erb"
         end
       end
 
       def delete_public_files_if_api_option
         if options[:api]
-          remove_file 'public/404.html'
-          remove_file 'public/422.html'
-          remove_file 'public/500.html'
-          remove_file 'public/apple-touch-icon-precomposed.png'
-          remove_file 'public/apple-touch-icon.png'
-          remove_file 'public/favicon.ico'
+          remove_file "public/404.html"
+          remove_file "public/422.html"
+          remove_file "public/500.html"
+          remove_file "public/apple-touch-icon-precomposed.png"
+          remove_file "public/apple-touch-icon.png"
+          remove_file "public/favicon.ico"
         end
       end
 
       def delete_js_folder_skipping_javascript
         if options[:skip_javascript]
-          remove_dir 'app/assets/javascripts'
+          remove_dir "app/assets/javascripts"
         end
       end
 
       def delete_assets_initializer_skipping_sprockets
         if options[:skip_sprockets]
-          remove_file 'config/initializers/assets.rb'
+          remove_file "config/initializers/assets.rb"
         end
       end
 
       def delete_application_record_skipping_active_record
         if options[:skip_active_record]
-          remove_file 'app/models/application_record.rb'
+          remove_file "app/models/application_record.rb"
         end
       end
 
       def delete_action_mailer_files_skipping_action_mailer
         if options[:skip_action_mailer]
-          remove_file 'app/mailers/application_mailer.rb'
-          remove_file 'app/views/layouts/mailer.html.erb'
-          remove_file 'app/views/layouts/mailer.text.erb'
+          remove_file "app/views/layouts/mailer.html.erb"
+          remove_file "app/views/layouts/mailer.text.erb"
+          remove_dir "app/mailers"
+          remove_dir "test/mailers"
         end
       end
 
       def delete_action_cable_files_skipping_action_cable
         if options[:skip_action_cable]
-          remove_file 'config/cable.yml'
-          remove_file 'app/assets/javascripts/cable.js'
-          remove_dir 'app/channels'
+          remove_file "app/assets/javascripts/cable.js"
+          remove_dir "app/channels"
         end
       end
 
       def delete_non_api_initializers_if_api_option
         if options[:api]
-          remove_file 'config/initializers/session_store.rb'
-          remove_file 'config/initializers/cookies_serializer.rb'
+          remove_file "config/initializers/cookies_serializer.rb"
+          remove_file "config/initializers/content_security_policy.rb"
         end
       end
 
       def delete_api_initializers
         unless options[:api]
-          remove_file 'config/initializers/cors.rb'
+          remove_file "config/initializers/cors.rb"
         end
       end
 
+      def delete_new_framework_defaults
+        unless options[:update]
+          remove_file "config/initializers/new_framework_defaults_5_2.rb"
+        end
+      end
+
+      def delete_bin_yarn_if_skip_yarn_option
+        remove_file "bin/yarn" if options[:skip_yarn]
+      end
+
       def finish_template
         build(:leftovers)
       end
 
       public_task :apply_rails_template, :run_bundle
-      public_task :generate_spring_binstubs
+      public_task :run_webpack, :generate_spring_binstubs
+      public_task :run_active_storage
 
       def run_after_bundle_callbacks
         @after_bundle_callbacks.each(&:call)
       end
 
-    protected
-
       def self.banner
-        "rails new #{self.arguments.map(&:usage).join(' ')} [options]"
+        "rails new #{arguments.map(&:usage).join(' ')} [options]"
       end
 
+    private
+
       # Define file as an alias to create_file for backwards compatibility.
       def file(*args, &block)
         create_file(*args, &block)
       end
 
       def app_name
-        @app_name ||= (defined_app_const_base? ? defined_app_name : File.basename(destination_root)).tr('\\', '').tr(". ", "_")
+        @app_name ||= (defined_app_const_base? ? defined_app_name : File.basename(destination_root)).tr('\\', "").tr(". ", "_")
       end
 
       def defined_app_name
@@ -381,7 +496,7 @@ module Rails
       alias :defined_app_const_base? :defined_app_const_base
 
       def app_const_base
-        @app_const_base ||= defined_app_const_base || app_name.gsub(/\W/, '_').squeeze('_').camelize
+        @app_const_base ||= defined_app_const_base || app_name.gsub(/\W/, "_").squeeze("_").camelize
       end
       alias :camelized :app_const_base
 
@@ -401,10 +516,6 @@ module Rails
         end
       end
 
-      def app_secret
-        SecureRandom.hex(64)
-      end
-
       def mysql_socket
         @mysql_socket ||= [
           "/tmp/mysql.sock",                        # default
@@ -416,7 +527,7 @@ module Rails
           "/opt/local/var/run/mysql4/mysqld.sock",  # mac + darwinports + mysql4
           "/opt/local/var/run/mysql5/mysqld.sock",  # mac + darwinports + mysql5
           "/opt/lampp/var/mysql/mysql.sock"         # xampp for linux
-        ].find { |f| File.exist?(f) } unless RbConfig::CONFIG['host_os'] =~ /mswin|mingw/
+        ].find { |f| File.exist?(f) } unless Gem.win_platform?
       end
 
       def get_builder_class
@@ -444,14 +555,14 @@ module Rails
       end
 
       def self.default_rc_file
-        File.expand_path('~/.railsrc')
+        File.expand_path("~/.railsrc")
       end
 
       private
 
         def handle_version_request!(argument)
-          if ['--version', '-v'].include?(argument)
-            require 'rails/version'
+          if ["--version", "-v"].include?(argument)
+            require "rails/version"
             puts "Rails #{Rails::VERSION::STRING}"
             exit(0)
           end
@@ -461,20 +572,20 @@ module Rails
           if argument == "new"
             yield
           else
-            ['--help'] + argv.drop(1)
+            ["--help"] + argv.drop(1)
           end
         end
 
         def handle_rails_rc!(argv)
-          if argv.find { |arg| arg == '--no-rc' }
-            argv.reject { |arg| arg == '--no-rc' }
+          if argv.find { |arg| arg == "--no-rc" }
+            argv.reject { |arg| arg == "--no-rc" }
           else
             railsrc(argv) { |rc_argv, rc| insert_railsrc_into_argv!(rc_argv, rc) }
           end
         end
 
         def railsrc(argv)
-          if (customrc = argv.index{ |x| x.include?("--rc=") })
+          if (customrc = argv.index { |x| x.include?("--rc=") })
             fname = File.expand_path(argv[customrc].gsub(/--rc=/, ""))
             yield(argv.take(customrc) + argv.drop(customrc + 1), fname)
           else
diff --git a/railties/lib/rails/generators/rails/app/templates/Gemfile b/railties/lib/rails/generators/rails/app/templates/Gemfile.tt
index 86143ca1f1..23bb89f4ce 100644
--- a/railties/lib/rails/generators/rails/app/templates/Gemfile
+++ b/railties/lib/rails/generators/rails/app/templates/Gemfile.tt
@@ -1,5 +1,11 @@
 source 'https://rubygems.org'
+git_source(:github) { |repo| "https://github.com/#{repo}.git" }
 
+ruby <%= "'#{RUBY_VERSION}'" -%>
+
+<% unless gemfile_entries.first.comment -%>
+
+<% end -%>
 <% gemfile_entries.each do |gem| -%>
 <% if gem.comment -%>
 
@@ -14,10 +20,20 @@ source 'https://rubygems.org'
 
 # Use ActiveModel has_secure_password
 # gem 'bcrypt', '~> 3.1.7'
+<% unless skip_active_storage? -%>
+
+# Use ActiveStorage variant
+# gem 'mini_magick', '~> 4.8'
+<% end -%>
 
 # Use Capistrano for deployment
 # gem 'capistrano-rails', group: :development
 
+<% if depend_on_bootsnap? -%>
+# Reduces boot times through caching; required in config/boot.rb
+gem 'bootsnap', '>= 1.1.0', require: false
+
+<%- end -%>
 <%- if options.api? -%>
 # Use Rack CORS for handling Cross-Origin Resource Sharing (CORS), making cross-origin AJAX possible
 # gem 'rack-cors'
@@ -26,20 +42,20 @@ source 'https://rubygems.org'
 <% if RUBY_ENGINE == 'ruby' -%>
 group :development, :test do
   # Call 'byebug' anywhere in the code to stop execution and get a debugger console
-  gem 'byebug', platform: :mri
+  gem 'byebug', platforms: [:mri, :mingw, :x64_mingw]
 end
 
 group :development do
 <%- unless options.api? -%>
-  # Access an IRB console on exception pages or by using <%%= console %> anywhere in the code.
+  # Access an interactive console on exception pages or by calling 'console' anywhere in the code.
   <%- if options.dev? || options.edge? -%>
   gem 'web-console', github: 'rails/web-console'
   <%- else -%>
-  gem 'web-console'
+  gem 'web-console', '>= 3.3.0'
   <%- end -%>
 <%- end -%>
 <% if depend_on_listen? -%>
-  gem 'listen', '~> 3.0.5'
+  gem 'listen', '>= 3.0.5', '< 3.2'
 <% end -%>
 <% if spring_install? -%>
   # Spring speeds up development by keeping your application running in the background. Read more: https://github.com/rails/spring
@@ -49,6 +65,16 @@ group :development do
 <% end -%>
 <% end -%>
 end
+
+<%- if depends_on_system_test? -%>
+group :test do
+  # Adds support for Capybara system testing and selenium driver
+  gem 'capybara', '~> 2.15'
+  gem 'selenium-webdriver'
+  # Easy installation and use of chromedriver to run system tests with Chrome
+  gem 'chromedriver-helper'
+end
+<%- end -%>
 <% end -%>
 
 # Windows does not include zoneinfo files, so bundle the tzinfo-data gem
diff --git a/railties/lib/rails/generators/rails/app/templates/README.md b/railties/lib/rails/generators/rails/app/templates/README.md.tt
index 7db80e4ca1..7db80e4ca1 100644
--- a/railties/lib/rails/generators/rails/app/templates/README.md
+++ b/railties/lib/rails/generators/rails/app/templates/README.md.tt
diff --git a/railties/lib/rails/generators/rails/app/templates/Rakefile b/railties/lib/rails/generators/rails/app/templates/Rakefile.tt
index e85f913914..e85f913914 100644
--- a/railties/lib/rails/generators/rails/app/templates/Rakefile
+++ b/railties/lib/rails/generators/rails/app/templates/Rakefile.tt
diff --git a/railties/lib/rails/generators/rails/app/templates/app/assets/javascripts/application.js.tt b/railties/lib/rails/generators/rails/app/templates/app/assets/javascripts/application.js.tt
index c88426ec06..5183bcd256 100644
--- a/railties/lib/rails/generators/rails/app/templates/app/assets/javascripts/application.js.tt
+++ b/railties/lib/rails/generators/rails/app/templates/app/assets/javascripts/application.js.tt
@@ -1,8 +1,8 @@
 // This is a manifest file that'll be compiled into application.js, which will include all the files
 // listed below.
 //
-// Any JavaScript/Coffee file within this directory, lib/assets/javascripts, vendor/assets/javascripts,
-// or any plugin's vendor/assets/javascripts directory can be referenced here using a relative path.
+// Any JavaScript/Coffee file within this directory, lib/assets/javascripts, or any plugin's
+// vendor/assets/javascripts directory can be referenced here using a relative path.
 //
 // It's not advisable to add code directly here, but if you do, it'll appear at the bottom of the
 // compiled file. JavaScript code in this file should be added after the last require_* statement.
@@ -11,9 +11,11 @@
 // about supported directives.
 //
 <% unless options[:skip_javascript] -%>
-//= require <%= options[:javascript] %>
-//= require <%= options[:javascript] %>_ujs
-<% if gemfile_entries.any? { |m| m.name == "turbolinks" } -%>
+//= require rails-ujs
+<% unless skip_active_storage? -%>
+//= require activestorage
+<% end -%>
+<% unless options[:skip_turbolinks] -%>
 //= require turbolinks
 <% end -%>
 <% end -%>
diff --git a/railties/lib/rails/generators/rails/app/templates/app/assets/javascripts/cable.js b/railties/lib/rails/generators/rails/app/templates/app/assets/javascripts/cable.js.tt
index 71ee1e66de..739aa5f022 100644
--- a/railties/lib/rails/generators/rails/app/templates/app/assets/javascripts/cable.js
+++ b/railties/lib/rails/generators/rails/app/templates/app/assets/javascripts/cable.js.tt
@@ -1,5 +1,5 @@
 // Action Cable provides the framework to deal with WebSockets in Rails.
-// You can generate new channels where WebSocket features live using the rails generate channel command.
+// You can generate new channels where WebSocket features live using the `rails generate channel` command.
 //
 //= require action_cable
 //= require_self
diff --git a/railties/lib/rails/generators/rails/app/templates/app/assets/stylesheets/application.css.tt b/railties/lib/rails/generators/rails/app/templates/app/assets/stylesheets/application.css.tt
new file mode 100644
index 0000000000..d05ea0f511
--- /dev/null
+++ b/railties/lib/rails/generators/rails/app/templates/app/assets/stylesheets/application.css.tt
@@ -0,0 +1,15 @@
+/*
+ * This is a manifest file that'll be compiled into application.css, which will include all the files
+ * listed below.
+ *
+ * Any CSS and SCSS file within this directory, lib/assets/stylesheets, or any plugin's
+ * vendor/assets/stylesheets directory can be referenced here using a relative path.
+ *
+ * You're free to add application-wide styles to this file and they'll appear at the bottom of the
+ * compiled file so the styles you add here take precedence over styles defined in any other CSS/SCSS
+ * files in this directory. Styles in this file should be added after the last require_* statement.
+ * It is generally better to create a new file per style scope.
+ *
+ *= require_tree .
+ *= require_self
+ */
diff --git a/railties/lib/rails/generators/rails/app/templates/app/channels/application_cable/channel.rb.tt b/railties/lib/rails/generators/rails/app/templates/app/channels/application_cable/channel.rb.tt
new file mode 100644
index 0000000000..d672697283
--- /dev/null
+++ b/railties/lib/rails/generators/rails/app/templates/app/channels/application_cable/channel.rb.tt
@@ -0,0 +1,4 @@
+module ApplicationCable
+  class Channel < ActionCable::Channel::Base
+  end
+end
diff --git a/railties/lib/rails/generators/rails/app/templates/app/channels/application_cable/connection.rb.tt b/railties/lib/rails/generators/rails/app/templates/app/channels/application_cable/connection.rb.tt
new file mode 100644
index 0000000000..0ff5442f47
--- /dev/null
+++ b/railties/lib/rails/generators/rails/app/templates/app/channels/application_cable/connection.rb.tt
@@ -0,0 +1,4 @@
+module ApplicationCable
+  class Connection < ActionCable::Connection::Base
+  end
+end
diff --git a/railties/lib/rails/generators/rails/app/templates/app/controllers/application_controller.rb.tt b/railties/lib/rails/generators/rails/app/templates/app/controllers/application_controller.rb.tt
index 413354186d..938eff8ed0 100644
--- a/railties/lib/rails/generators/rails/app/templates/app/controllers/application_controller.rb.tt
+++ b/railties/lib/rails/generators/rails/app/templates/app/controllers/application_controller.rb.tt
@@ -1,5 +1,2 @@
-class ApplicationController < ActionController::<%= options[:api] ? "API" : "Base" %>
-<%- unless options[:api] -%>
-  protect_from_forgery with: :exception
-<%- end -%>
+class ApplicationController < ActionController::<%= options.api? ? "API" : "Base" %>
 end
diff --git a/railties/lib/rails/generators/rails/app/templates/app/helpers/application_helper.rb b/railties/lib/rails/generators/rails/app/templates/app/helpers/application_helper.rb.tt
index de6be7945c..de6be7945c 100644
--- a/railties/lib/rails/generators/rails/app/templates/app/helpers/application_helper.rb
+++ b/railties/lib/rails/generators/rails/app/templates/app/helpers/application_helper.rb.tt
diff --git a/railties/lib/rails/generators/rails/app/templates/app/jobs/application_job.rb b/railties/lib/rails/generators/rails/app/templates/app/jobs/application_job.rb.tt
index a009ace51c..a009ace51c 100644
--- a/railties/lib/rails/generators/rails/app/templates/app/jobs/application_job.rb
+++ b/railties/lib/rails/generators/rails/app/templates/app/jobs/application_job.rb.tt
diff --git a/railties/lib/rails/generators/rails/app/templates/app/mailers/application_mailer.rb b/railties/lib/rails/generators/rails/app/templates/app/mailers/application_mailer.rb.tt
index 286b2239d1..286b2239d1 100644
--- a/railties/lib/rails/generators/rails/app/templates/app/mailers/application_mailer.rb
+++ b/railties/lib/rails/generators/rails/app/templates/app/mailers/application_mailer.rb.tt
diff --git a/railties/lib/rails/generators/rails/app/templates/app/models/application_record.rb b/railties/lib/rails/generators/rails/app/templates/app/models/application_record.rb.tt
index 10a4cba84d..10a4cba84d 100644
--- a/railties/lib/rails/generators/rails/app/templates/app/models/application_record.rb
+++ b/railties/lib/rails/generators/rails/app/templates/app/models/application_record.rb.tt
diff --git a/railties/lib/rails/generators/rails/app/templates/app/views/layouts/application.html.erb.tt b/railties/lib/rails/generators/rails/app/templates/app/views/layouts/application.html.erb.tt
index d51f79bd49..5460155b3e 100644
--- a/railties/lib/rails/generators/rails/app/templates/app/views/layouts/application.html.erb.tt
+++ b/railties/lib/rails/generators/rails/app/templates/app/views/layouts/application.html.erb.tt
@@ -7,7 +7,7 @@
     <%- if options[:skip_javascript] -%>
     <%%= stylesheet_link_tag    'application', media: 'all' %>
     <%- else -%>
-      <%- if gemfile_entries.any? { |m| m.name == 'turbolinks' } -%>
+      <%- unless options[:skip_turbolinks] -%>
     <%%= stylesheet_link_tag    'application', media: 'all', 'data-turbolinks-track': 'reload' %>
     <%%= javascript_include_tag 'application', 'data-turbolinks-track': 'reload' %>
       <%- else -%>
diff --git a/railties/lib/rails/generators/rails/app/templates/bin/bundle b/railties/lib/rails/generators/rails/app/templates/bin/bundle
deleted file mode 100644
index 1123dcf501..0000000000
--- a/railties/lib/rails/generators/rails/app/templates/bin/bundle
+++ /dev/null
@@ -1,2 +0,0 @@
-ENV['BUNDLE_GEMFILE'] ||= File.expand_path('../../Gemfile', __FILE__)
-load Gem.bin_path('bundler', 'bundle')
diff --git a/railties/lib/rails/generators/rails/app/templates/config/boot.rb b/railties/lib/rails/generators/rails/app/templates/bin/bundle.tt
index 30f5120df6..a84f0afe47 100644
--- a/railties/lib/rails/generators/rails/app/templates/config/boot.rb
+++ b/railties/lib/rails/generators/rails/app/templates/bin/bundle.tt
@@ -1,3 +1,2 @@
 ENV['BUNDLE_GEMFILE'] ||= File.expand_path('../Gemfile', __dir__)
-
-require 'bundler/setup' # Set up gems listed in the Gemfile.
+load Gem.bin_path('bundler', 'bundle')
diff --git a/railties/lib/rails/generators/rails/app/templates/bin/rails b/railties/lib/rails/generators/rails/app/templates/bin/rails.tt
index 513a2e0183..513a2e0183 100644
--- a/railties/lib/rails/generators/rails/app/templates/bin/rails
+++ b/railties/lib/rails/generators/rails/app/templates/bin/rails.tt
diff --git a/railties/lib/rails/generators/rails/app/templates/bin/rake b/railties/lib/rails/generators/rails/app/templates/bin/rake.tt
index d14fc8395b..d14fc8395b 100644
--- a/railties/lib/rails/generators/rails/app/templates/bin/rake
+++ b/railties/lib/rails/generators/rails/app/templates/bin/rake.tt
diff --git a/railties/lib/rails/generators/rails/app/templates/bin/setup b/railties/lib/rails/generators/rails/app/templates/bin/setup.tt
index acae810c1a..233b5a1d95 100644
--- a/railties/lib/rails/generators/rails/app/templates/bin/setup
+++ b/railties/lib/rails/generators/rails/app/templates/bin/setup.tt
@@ -1,9 +1,8 @@
-require 'pathname'
 require 'fileutils'
 include FileUtils
 
 # path to your application root.
-APP_ROOT = Pathname.new File.expand_path('../../', __FILE__)
+APP_ROOT = File.expand_path('..', __dir__)
 
 def system!(*args)
   system(*args) || abort("\n== Command #{args} failed ==")
@@ -16,6 +15,12 @@ chdir APP_ROOT do
   puts '== Installing dependencies =='
   system! 'gem install bundler --conservative'
   system('bundle check') || system!('bundle install')
+<% unless options.skip_yarn? -%>
+
+  # Install JavaScript dependencies if using Yarn
+  # system('bin/yarn')
+<% end -%>
+<% unless options.skip_active_record? -%>
 
   # puts "\n== Copying sample files =="
   # unless File.exist?('config/database.yml')
@@ -24,6 +29,7 @@ chdir APP_ROOT do
 
   puts "\n== Preparing database =="
   system! 'bin/rails db:setup'
+<% end -%>
 
   puts "\n== Removing old logs and tempfiles =="
   system! 'bin/rails log:clear tmp:clear'
diff --git a/railties/lib/rails/generators/rails/app/templates/bin/update b/railties/lib/rails/generators/rails/app/templates/bin/update.tt
index 770a605fed..70cc71d83b 100644
--- a/railties/lib/rails/generators/rails/app/templates/bin/update
+++ b/railties/lib/rails/generators/rails/app/templates/bin/update.tt
@@ -1,9 +1,8 @@
-require 'pathname'
 require 'fileutils'
 include FileUtils
 
 # path to your application root.
-APP_ROOT = Pathname.new File.expand_path('../../', __FILE__)
+APP_ROOT = File.expand_path('..', __dir__)
 
 def system!(*args)
   system(*args) || abort("\n== Command #{args} failed ==")
@@ -16,9 +15,16 @@ chdir APP_ROOT do
   puts '== Installing dependencies =='
   system! 'gem install bundler --conservative'
   system('bundle check') || system!('bundle install')
+<% unless options.skip_yarn? -%>
+
+  # Install JavaScript dependencies if using Yarn
+  # system('bin/yarn')
+<% end -%>
+<% unless options.skip_active_record? -%>
 
   puts "\n== Updating database =="
   system! 'bin/rails db:migrate'
+<% end -%>
 
   puts "\n== Removing old logs and tempfiles =="
   system! 'bin/rails log:clear tmp:clear'
diff --git a/railties/lib/rails/generators/rails/app/templates/bin/yarn.tt b/railties/lib/rails/generators/rails/app/templates/bin/yarn.tt
new file mode 100644
index 0000000000..b4e4d95286
--- /dev/null
+++ b/railties/lib/rails/generators/rails/app/templates/bin/yarn.tt
@@ -0,0 +1,10 @@
+APP_ROOT = File.expand_path('..', __dir__)
+Dir.chdir(APP_ROOT) do
+  begin
+    exec "yarnpkg #{ARGV.join(' ')}"
+  rescue Errno::ENOENT
+    $stderr.puts "Yarn executable was not detected in the system."
+    $stderr.puts "Download Yarn at https://yarnpkg.com/en/docs/install"
+    exit 1
+  end
+end
diff --git a/railties/lib/rails/generators/rails/app/templates/config.ru b/railties/lib/rails/generators/rails/app/templates/config.ru.tt
index f7ba0b527b..f7ba0b527b 100644
--- a/railties/lib/rails/generators/rails/app/templates/config.ru
+++ b/railties/lib/rails/generators/rails/app/templates/config.ru.tt
diff --git a/railties/lib/rails/generators/rails/app/templates/config/application.rb b/railties/lib/rails/generators/rails/app/templates/config/application.rb.tt
index c0a0bd0a3e..9e03e86771 100644
--- a/railties/lib/rails/generators/rails/app/templates/config/application.rb
+++ b/railties/lib/rails/generators/rails/app/templates/config/application.rb.tt
@@ -8,6 +8,7 @@ require "rails"
 require "active_model/railtie"
 require "active_job/railtie"
 <%= comment_if :skip_active_record %>require "active_record/railtie"
+<%= comment_if :skip_active_storage %>require "active_storage/engine"
 require "action_controller/railtie"
 <%= comment_if :skip_action_mailer %>require "action_mailer/railtie"
 require "action_view/railtie"
@@ -22,15 +23,22 @@ Bundler.require(*Rails.groups)
 
 module <%= app_const_base %>
   class Application < Rails::Application
+    # Initialize configuration defaults for originally generated Rails version.
+    config.load_defaults <%= Rails::VERSION::STRING.to_f %>
+
     # Settings in config/environments/* take precedence over those specified here.
     # Application configuration should go into files in config/initializers
     # -- all .rb files in that directory are automatically loaded.
-<%- if options[:api] -%>
+<%- if options.api? -%>
 
     # Only loads a smaller set of middleware suitable for API only apps.
     # Middleware like session, flash, cookies can be added back manually.
     # Skip views, helpers and assets when generating a new resource.
     config.api_only = true
+<%- elsif !depends_on_system_test? -%>
+
+    # Don't generate system test files.
+    config.generators.system_tests = nil
 <%- end -%>
   end
 end
diff --git a/railties/lib/rails/generators/rails/app/templates/config/boot.rb.tt b/railties/lib/rails/generators/rails/app/templates/config/boot.rb.tt
new file mode 100644
index 0000000000..720d36a2a4
--- /dev/null
+++ b/railties/lib/rails/generators/rails/app/templates/config/boot.rb.tt
@@ -0,0 +1,10 @@
+ENV['BUNDLE_GEMFILE'] ||= File.expand_path('../Gemfile', __dir__)
+
+require 'bundler/setup' # Set up gems listed in the Gemfile.
+<% if depend_on_bootsnap? -%>
+require 'bootsnap/setup' # Speed up boot time by caching expensive operations.
+<%- end -%>
+
+if %w[s server c console].any? { |a| ARGV.include?(a) }
+  puts "=> Booting Rails"
+end
diff --git a/railties/lib/rails/generators/rails/app/templates/config/cable.yml b/railties/lib/rails/generators/rails/app/templates/config/cable.yml
deleted file mode 100644
index 0bbde6f74f..0000000000
--- a/railties/lib/rails/generators/rails/app/templates/config/cable.yml
+++ /dev/null
@@ -1,9 +0,0 @@
-development:
-  adapter: async
-
-test:
-  adapter: async
-
-production:
-  adapter: redis
-  url: redis://localhost:6379/1
diff --git a/railties/lib/rails/generators/rails/app/templates/config/cable.yml.tt b/railties/lib/rails/generators/rails/app/templates/config/cable.yml.tt
new file mode 100644
index 0000000000..8e53156c71
--- /dev/null
+++ b/railties/lib/rails/generators/rails/app/templates/config/cable.yml.tt
@@ -0,0 +1,10 @@
+development:
+  adapter: async
+
+test:
+  adapter: async
+
+production:
+  adapter: redis
+  url: <%%= ENV.fetch("REDIS_URL") { "redis://localhost:6379/1" } %>
+  channel_prefix: <%= app_name %>_production
diff --git a/railties/lib/rails/generators/rails/app/templates/config/databases/frontbase.yml b/railties/lib/rails/generators/rails/app/templates/config/databases/frontbase.yml.tt
index 917b52e535..917b52e535 100644
--- a/railties/lib/rails/generators/rails/app/templates/config/databases/frontbase.yml
+++ b/railties/lib/rails/generators/rails/app/templates/config/databases/frontbase.yml.tt
diff --git a/railties/lib/rails/generators/rails/app/templates/config/databases/ibm_db.yml b/railties/lib/rails/generators/rails/app/templates/config/databases/ibm_db.yml.tt
index d40117a27f..d40117a27f 100644
--- a/railties/lib/rails/generators/rails/app/templates/config/databases/ibm_db.yml
+++ b/railties/lib/rails/generators/rails/app/templates/config/databases/ibm_db.yml.tt
diff --git a/railties/lib/rails/generators/rails/app/templates/config/databases/jdbc.yml b/railties/lib/rails/generators/rails/app/templates/config/databases/jdbc.yml.tt
index 563be77710..563be77710 100644
--- a/railties/lib/rails/generators/rails/app/templates/config/databases/jdbc.yml
+++ b/railties/lib/rails/generators/rails/app/templates/config/databases/jdbc.yml.tt
diff --git a/railties/lib/rails/generators/rails/app/templates/config/databases/jdbcmysql.yml b/railties/lib/rails/generators/rails/app/templates/config/databases/jdbcmysql.yml.tt
index a2b2a64ba6..2a67bdca25 100644
--- a/railties/lib/rails/generators/rails/app/templates/config/databases/jdbcmysql.yml
+++ b/railties/lib/rails/generators/rails/app/templates/config/databases/jdbcmysql.yml.tt
@@ -1,4 +1,4 @@
-# MySQL. Versions 5.0 and up are supported.
+# MySQL. Versions 5.1.10 and up are supported.
 #
 # Install the MySQL driver:
 #   gem install activerecord-jdbcmysql-adapter
@@ -7,7 +7,7 @@
 # gem 'activerecord-jdbcmysql-adapter'
 #
 # And be sure to use new-style password hashing:
-#   http://dev.mysql.com/doc/refman/5.7/en/old-client.html
+#   https://dev.mysql.com/doc/refman/5.7/en/password-hashing.html
 #
 default: &default
   adapter: mysql
diff --git a/railties/lib/rails/generators/rails/app/templates/config/databases/jdbcpostgresql.yml b/railties/lib/rails/generators/rails/app/templates/config/databases/jdbcpostgresql.yml.tt
index 70df04079d..70df04079d 100644
--- a/railties/lib/rails/generators/rails/app/templates/config/databases/jdbcpostgresql.yml
+++ b/railties/lib/rails/generators/rails/app/templates/config/databases/jdbcpostgresql.yml.tt
diff --git a/railties/lib/rails/generators/rails/app/templates/config/databases/jdbcsqlite3.yml b/railties/lib/rails/generators/rails/app/templates/config/databases/jdbcsqlite3.yml.tt
index 371415e6a8..371415e6a8 100644
--- a/railties/lib/rails/generators/rails/app/templates/config/databases/jdbcsqlite3.yml
+++ b/railties/lib/rails/generators/rails/app/templates/config/databases/jdbcsqlite3.yml.tt
diff --git a/railties/lib/rails/generators/rails/app/templates/config/databases/mysql.yml b/railties/lib/rails/generators/rails/app/templates/config/databases/mysql.yml.tt
index d987cf303b..04afaa0596 100644
--- a/railties/lib/rails/generators/rails/app/templates/config/databases/mysql.yml
+++ b/railties/lib/rails/generators/rails/app/templates/config/databases/mysql.yml.tt
@@ -1,4 +1,4 @@
-# MySQL. Versions 5.0 and up are supported.
+# MySQL. Versions 5.1.10 and up are supported.
 #
 # Install the MySQL driver
 #   gem install mysql2
@@ -7,7 +7,7 @@
 #   gem 'mysql2'
 #
 # And be sure to use new-style password hashing:
-#   http://dev.mysql.com/doc/refman/5.7/en/old-client.html
+#   https://dev.mysql.com/doc/refman/5.7/en/password-hashing.html
 #
 default: &default
   adapter: mysql2
diff --git a/railties/lib/rails/generators/rails/app/templates/config/databases/oracle.yml b/railties/lib/rails/generators/rails/app/templates/config/databases/oracle.yml.tt
index d2499ea4fb..6da0601b24 100644
--- a/railties/lib/rails/generators/rails/app/templates/config/databases/oracle.yml
+++ b/railties/lib/rails/generators/rails/app/templates/config/databases/oracle.yml.tt
@@ -1,4 +1,4 @@
-# Oracle/OCI 8i, 9, 10g
+# Oracle/OCI 11g or higher recommended
 #
 # Requires Ruby/OCI8:
 #  https://github.com/kubo/ruby-oci8
@@ -17,7 +17,7 @@
 #  cursor_sharing: similar
 #
 default: &default
-  adapter: oracle
+  adapter: oracle_enhanced
   pool: <%%= ENV.fetch("RAILS_MAX_THREADS") { 5 } %>
   username: <%= app_name %>
   password:
@@ -45,7 +45,9 @@ test:
 # On Heroku and other platform providers, you may have a full connection URL
 # available as an environment variable. For example:
 #
-#   DATABASE_URL="oracle://myuser:mypass@localhost/somedatabase"
+#   DATABASE_URL="oracle-enhanced://myuser:mypass@localhost/somedatabase"
+#
+# Note that the adapter name uses a dash instead of an underscore.
 #
 # You can use this database configuration with:
 #
diff --git a/railties/lib/rails/generators/rails/app/templates/config/databases/postgresql.yml b/railties/lib/rails/generators/rails/app/templates/config/databases/postgresql.yml.tt
index bd5c0b10f6..145cfb7f74 100644
--- a/railties/lib/rails/generators/rails/app/templates/config/databases/postgresql.yml
+++ b/railties/lib/rails/generators/rails/app/templates/config/databases/postgresql.yml.tt
@@ -17,7 +17,7 @@
 default: &default
   adapter: postgresql
   encoding: unicode
-  # For details on connection pooling, see rails configuration guide
+  # For details on connection pooling, see Rails configuration guide
   # http://guides.rubyonrails.org/configuring.html#database-pooling
   pool: <%%= ENV.fetch("RAILS_MAX_THREADS") { 5 } %>
 
diff --git a/railties/lib/rails/generators/rails/app/templates/config/databases/sqlite3.yml b/railties/lib/rails/generators/rails/app/templates/config/databases/sqlite3.yml.tt
index 9510568124..9510568124 100644
--- a/railties/lib/rails/generators/rails/app/templates/config/databases/sqlite3.yml
+++ b/railties/lib/rails/generators/rails/app/templates/config/databases/sqlite3.yml.tt
diff --git a/railties/lib/rails/generators/rails/app/templates/config/databases/sqlserver.yml b/railties/lib/rails/generators/rails/app/templates/config/databases/sqlserver.yml.tt
index c223d6bc62..049de65f22 100644
--- a/railties/lib/rails/generators/rails/app/templates/config/databases/sqlserver.yml
+++ b/railties/lib/rails/generators/rails/app/templates/config/databases/sqlserver.yml.tt
@@ -1,4 +1,4 @@
-# SQL Server (2005 or higher recommended)
+# SQL Server (2012 or higher required)
 #
 # Install the adapters and driver
 #   gem install tiny_tds
@@ -8,29 +8,12 @@
 #   gem 'tiny_tds'
 #   gem 'activerecord-sqlserver-adapter'
 #
-# You should make sure freetds is configured correctly first.
-# freetds.conf contains host/port/protocol_versions settings.
-# http://freetds.schemamania.org/userguide/freetdsconf.htm
-#
-# A typical Microsoft server
-#   [mssql]
-#   host = mssqlserver.yourdomain.com
-#   port = 1433
-#   tds version = 7.1
-
-# If you can connect with "tsql -S servername", your basic FreeTDS installation is working.
-# 'man tsql' for more info
-# Set timeout to a larger number if valid queries against a live db fail
-#
 default: &default
   adapter: sqlserver
   encoding: utf8
-  pool: <%%= ENV.fetch("RAILS_MAX_THREADS") { 5 } %>
-  reconnect: false
-  username: <%= app_name %>
-  password:
-  timeout: 25
-  dataserver: from_freetds.conf
+  username: sa
+  password: <%%= ENV['SA_PASSWORD'] %>
+  host: localhost
 
 development:
   <<: *default
diff --git a/railties/lib/rails/generators/rails/app/templates/config/environment.rb b/railties/lib/rails/generators/rails/app/templates/config/environment.rb.tt
index 426333bb46..426333bb46 100644
--- a/railties/lib/rails/generators/rails/app/templates/config/environment.rb
+++ b/railties/lib/rails/generators/rails/app/templates/config/environment.rb.tt
diff --git a/railties/lib/rails/generators/rails/app/templates/config/environments/development.rb.tt b/railties/lib/rails/generators/rails/app/templates/config/environments/development.rb.tt
index f3ccf95045..a87649b50f 100644
--- a/railties/lib/rails/generators/rails/app/templates/config/environments/development.rb.tt
+++ b/railties/lib/rails/generators/rails/app/templates/config/environments/development.rb.tt
@@ -13,18 +13,24 @@ Rails.application.configure do
   config.consider_all_requests_local = true
 
   # Enable/disable caching. By default caching is disabled.
-  if Rails.root.join('tmp/caching-dev.txt').exist?
+  # Run rails dev:cache to toggle caching.
+  if Rails.root.join('tmp', 'caching-dev.txt').exist?
     config.action_controller.perform_caching = true
 
     config.cache_store = :memory_store
     config.public_file_server.headers = {
-      'Cache-Control' => 'public, max-age=172800'
+      'Cache-Control' => "public, max-age=#{2.days.to_i}"
     }
   else
     config.action_controller.perform_caching = false
 
     config.cache_store = :null_store
   end
+  <%- unless skip_active_storage? -%>
+
+  # Store uploaded files on the local file system (see config/storage.yml for options)
+  config.active_storage.service = :local
+  <%- end -%>
   <%- unless options.skip_action_mailer? -%>
 
   # Don't care if the mailer can't send.
@@ -40,6 +46,9 @@ Rails.application.configure do
   # Raise an error on page load if there are pending migrations.
   config.active_record.migration_error = :page_load
 
+  # Highlight code that triggered database queries in logs.
+  config.active_record.verbose_query_logs = true
+
   <%- end -%>
   <%- unless options.skip_sprockets? -%>
   # Debug mode disables concatenation and preprocessing of assets.
diff --git a/railties/lib/rails/generators/rails/app/templates/config/environments/production.rb.tt b/railties/lib/rails/generators/rails/app/templates/config/environments/production.rb.tt
index 363af05459..4c0f36db98 100644
--- a/railties/lib/rails/generators/rails/app/templates/config/environments/production.rb.tt
+++ b/railties/lib/rails/generators/rails/app/templates/config/environments/production.rb.tt
@@ -14,21 +14,29 @@ Rails.application.configure do
   config.consider_all_requests_local       = false
   config.action_controller.perform_caching = true
 
+  # Ensures that a master key has been made available in either ENV["RAILS_MASTER_KEY"]
+  # or in config/master.key. This key is used to decrypt credentials (and other encrypted files).
+  # config.require_master_key = true
+
   # Disable serving static files from the `/public` folder by default since
   # Apache or NGINX already handles this.
   config.public_file_server.enabled = ENV['RAILS_SERVE_STATIC_FILES'].present?
 
   <%- unless options.skip_sprockets? -%>
+  <%- if options.skip_javascript? -%>
+  # Compress CSS.
+  <%- else -%>
   # Compress JavaScripts and CSS.
   config.assets.js_compressor = :uglifier
+  <%- end -%>
   # config.assets.css_compressor = :sass
 
   # Do not fallback to assets pipeline if a precompiled asset is missed.
   config.assets.compile = false
 
   # `config.assets.precompile` and `config.assets.version` have moved to config/initializers/assets.rb
-  <%- end -%>
 
+  <%- end -%>
   # Enable serving of images, stylesheets, and JavaScripts from an asset server.
   # config.action_controller.asset_host = 'http://assets.example.com'
 
@@ -36,13 +44,18 @@ Rails.application.configure do
   # config.action_dispatch.x_sendfile_header = 'X-Sendfile' # for Apache
   # config.action_dispatch.x_sendfile_header = 'X-Accel-Redirect' # for NGINX
 
+  <%- unless skip_active_storage? -%>
+  # Store uploaded files on the local file system (see config/storage.yml for options)
+  config.active_storage.service = :local
+
+  <%- end -%>
   <%- unless options[:skip_action_cable] -%>
   # Mount Action Cable outside main process or domain
   # config.action_cable.mount_path = nil
   # config.action_cable.url = 'wss://example.com/cable'
   # config.action_cable.allowed_request_origins = [ 'http://example.com', /http:\/\/example.*/ ]
-  <%- end -%>
 
+  <%- end -%>
   # Force all access to the app over SSL, use Strict-Transport-Security, and use secure cookies.
   # config.force_ssl = true
 
@@ -59,14 +72,15 @@ Rails.application.configure do
   # Use a real queuing backend for Active Job (and separate queues per environment)
   # config.active_job.queue_adapter     = :resque
   # config.active_job.queue_name_prefix = "<%= app_name %>_#{Rails.env}"
+
   <%- unless options.skip_action_mailer? -%>
   config.action_mailer.perform_caching = false
 
   # Ignore bad email addresses and do not raise email delivery errors.
   # Set this to true and configure the email server for immediate delivery to raise delivery errors.
   # config.action_mailer.raise_delivery_errors = false
-  <%- end -%>
 
+  <%- end -%>
   # Enable locale fallbacks for I18n (makes lookups for any locale fall back to
   # the I18n.default_locale when a translation cannot be found).
   config.i18n.fallbacks = true
@@ -84,7 +98,7 @@ Rails.application.configure do
   if ENV["RAILS_LOG_TO_STDOUT"].present?
     logger           = ActiveSupport::Logger.new(STDOUT)
     logger.formatter = config.log_formatter
-    config.logger = ActiveSupport::TaggedLogging.new(logger)
+    config.logger    = ActiveSupport::TaggedLogging.new(logger)
   end
   <%- unless options.skip_active_record? -%>
 
diff --git a/railties/lib/rails/generators/rails/app/templates/config/environments/test.rb.tt b/railties/lib/rails/generators/rails/app/templates/config/environments/test.rb.tt
index 42fee3b036..ff4c89219a 100644
--- a/railties/lib/rails/generators/rails/app/templates/config/environments/test.rb.tt
+++ b/railties/lib/rails/generators/rails/app/templates/config/environments/test.rb.tt
@@ -15,7 +15,7 @@ Rails.application.configure do
   # Configure public file server for tests with Cache-Control for performance.
   config.public_file_server.enabled = true
   config.public_file_server.headers = {
-    'Cache-Control' => 'public, max-age=3600'
+    'Cache-Control' => "public, max-age=#{1.hour.to_i}"
   }
 
   # Show full error reports and disable caching.
@@ -27,6 +27,12 @@ Rails.application.configure do
 
   # Disable request forgery protection in test environment.
   config.action_controller.allow_forgery_protection = false
+
+  <%- unless skip_active_storage? -%>
+  # Store uploaded files on the local file system in a temporary directory
+  config.active_storage.service = :test
+
+  <%- end -%>
   <%- unless options.skip_action_mailer? -%>
   config.action_mailer.perform_caching = false
 
@@ -34,8 +40,8 @@ Rails.application.configure do
   # The :test delivery method accumulates sent emails in the
   # ActionMailer::Base.deliveries array.
   config.action_mailer.delivery_method = :test
-  <%- end -%>
 
+  <%- end -%>
   # Print deprecation notices to the stderr.
   config.active_support.deprecation = :stderr
 
diff --git a/railties/lib/rails/generators/rails/app/templates/config/initializers/application_controller_renderer.rb.tt b/railties/lib/rails/generators/rails/app/templates/config/initializers/application_controller_renderer.rb.tt
new file mode 100644
index 0000000000..89d2efab2b
--- /dev/null
+++ b/railties/lib/rails/generators/rails/app/templates/config/initializers/application_controller_renderer.rb.tt
@@ -0,0 +1,8 @@
+# Be sure to restart your server when you modify this file.
+
+# ActiveSupport::Reloader.to_prepare do
+#   ApplicationController.renderer.defaults.merge!(
+#     http_host: 'example.org',
+#     https: false
+#   )
+# end
diff --git a/railties/lib/rails/generators/rails/app/templates/config/initializers/assets.rb.tt b/railties/lib/rails/generators/rails/app/templates/config/initializers/assets.rb.tt
index 01ef3e6630..51196ae743 100644
--- a/railties/lib/rails/generators/rails/app/templates/config/initializers/assets.rb.tt
+++ b/railties/lib/rails/generators/rails/app/templates/config/initializers/assets.rb.tt
@@ -3,9 +3,14 @@
 # Version of your assets, change this if you want to expire all your assets.
 Rails.application.config.assets.version = '1.0'
 
-# Add additional assets to the asset load path
+# Add additional assets to the asset load path.
 # Rails.application.config.assets.paths << Emoji.images_path
+<%- unless options[:skip_yarn] -%>
+# Add Yarn node_modules folder to the asset load path.
+Rails.application.config.assets.paths << Rails.root.join('node_modules')
+<%- end -%>
 
 # Precompile additional assets.
-# application.js, application.css, and all non-JS/CSS in app/assets folder are already added.
-# Rails.application.config.assets.precompile += %w( search.js )
+# application.js, application.css, and all non-JS/CSS in the app/assets
+# folder are already added.
+# Rails.application.config.assets.precompile += %w( admin.js admin.css )
diff --git a/railties/lib/rails/generators/rails/app/templates/config/initializers/backtrace_silencers.rb b/railties/lib/rails/generators/rails/app/templates/config/initializers/backtrace_silencers.rb.tt
index 59385cdf37..59385cdf37 100644
--- a/railties/lib/rails/generators/rails/app/templates/config/initializers/backtrace_silencers.rb
+++ b/railties/lib/rails/generators/rails/app/templates/config/initializers/backtrace_silencers.rb.tt
diff --git a/railties/lib/rails/generators/rails/app/templates/config/initializers/content_security_policy.rb.tt b/railties/lib/rails/generators/rails/app/templates/config/initializers/content_security_policy.rb.tt
new file mode 100644
index 0000000000..656ded4069
--- /dev/null
+++ b/railties/lib/rails/generators/rails/app/templates/config/initializers/content_security_policy.rb.tt
@@ -0,0 +1,20 @@
+# Define an application-wide content security policy
+# For further information see the following documentation
+# https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Content-Security-Policy
+
+Rails.application.config.content_security_policy do |p|
+  p.default_src :self, :https
+  p.font_src    :self, :https, :data
+  p.img_src     :self, :https, :data
+  p.object_src  :none
+  p.script_src  :self, :https
+  p.style_src   :self, :https, :unsafe_inline
+
+  # Specify URI for violation reports
+  # p.report_uri "/csp-violation-report-endpoint"
+end
+
+# Report CSP violations to a specified URI
+# For further information see the following documentation:
+# https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Content-Security-Policy-Report-Only
+# Rails.application.config.content_security_policy_report_only = true
diff --git a/railties/lib/rails/generators/rails/app/templates/config/initializers/cookies_serializer.rb b/railties/lib/rails/generators/rails/app/templates/config/initializers/cookies_serializer.rb.tt
index 5a6a32d371..5a6a32d371 100644
--- a/railties/lib/rails/generators/rails/app/templates/config/initializers/cookies_serializer.rb
+++ b/railties/lib/rails/generators/rails/app/templates/config/initializers/cookies_serializer.rb.tt
diff --git a/railties/lib/rails/generators/rails/app/templates/config/initializers/cors.rb b/railties/lib/rails/generators/rails/app/templates/config/initializers/cors.rb.tt
index 3b1c1b5ed1..3b1c1b5ed1 100644
--- a/railties/lib/rails/generators/rails/app/templates/config/initializers/cors.rb
+++ b/railties/lib/rails/generators/rails/app/templates/config/initializers/cors.rb.tt
diff --git a/railties/lib/rails/generators/rails/app/templates/config/initializers/filter_parameter_logging.rb b/railties/lib/rails/generators/rails/app/templates/config/initializers/filter_parameter_logging.rb.tt
index 4a994e1e7b..4a994e1e7b 100644
--- a/railties/lib/rails/generators/rails/app/templates/config/initializers/filter_parameter_logging.rb
+++ b/railties/lib/rails/generators/rails/app/templates/config/initializers/filter_parameter_logging.rb.tt
diff --git a/railties/lib/rails/generators/rails/app/templates/config/initializers/inflections.rb b/railties/lib/rails/generators/rails/app/templates/config/initializers/inflections.rb.tt
index ac033bf9dc..ac033bf9dc 100644
--- a/railties/lib/rails/generators/rails/app/templates/config/initializers/inflections.rb
+++ b/railties/lib/rails/generators/rails/app/templates/config/initializers/inflections.rb.tt
diff --git a/railties/lib/rails/generators/rails/app/templates/config/initializers/mime_types.rb b/railties/lib/rails/generators/rails/app/templates/config/initializers/mime_types.rb.tt
index dc1899682b..dc1899682b 100644
--- a/railties/lib/rails/generators/rails/app/templates/config/initializers/mime_types.rb
+++ b/railties/lib/rails/generators/rails/app/templates/config/initializers/mime_types.rb.tt
diff --git a/railties/lib/rails/generators/rails/app/templates/config/initializers/new_framework_defaults.rb.tt b/railties/lib/rails/generators/rails/app/templates/config/initializers/new_framework_defaults.rb.tt
deleted file mode 100644
index 991963b65e..0000000000
--- a/railties/lib/rails/generators/rails/app/templates/config/initializers/new_framework_defaults.rb.tt
+++ /dev/null
@@ -1,34 +0,0 @@
-# Be sure to restart your server when you modify this file.
-#
-# This file contains migration options to ease your Rails 5.0 upgrade.
-#
-<%- if options[:update] -%>
-# Once upgraded flip defaults one by one to migrate to the new default.
-#
-<%- end -%>
-# Read the Rails 5.0 release notes for more info on each option.
-<%- unless options[:api] -%>
-
-# Enable per-form CSRF tokens. Previous versions had false.
-Rails.application.config.action_controller.per_form_csrf_tokens = <%= options[:update] ? false : true %>
-
-# Enable origin-checking CSRF mitigation. Previous versions had false.
-Rails.application.config.action_controller.forgery_protection_origin_check = <%= options[:update] ? false : true %>
-<%- end -%>
-
-# Make Ruby 2.4 preserve the timezone of the receiver when calling `to_time`.
-# Previous versions had false.
-ActiveSupport.to_time_preserves_timezone = <%= options[:update] ? false : true %>
-<%- unless options[:skip_active_record] -%>
-
-# Require `belongs_to` associations by default. Previous versions had false.
-Rails.application.config.active_record.belongs_to_required_by_default = <%= options[:update] ? false : true %>
-<%- end -%>
-
-# Do not halt callback chains when a callback returns false. Previous versions had true.
-ActiveSupport.halt_callback_chains_on_return_false = <%= options[:update] ? true : false %>
-<%- unless options[:update] -%>
-
-# Configure SSL options to enable HSTS with subdomains. Previous versions had false.
-Rails.application.config.ssl_options = { hsts: { subdomains: true } }
-<%- end -%>
diff --git a/railties/lib/rails/generators/rails/app/templates/config/initializers/new_framework_defaults_5_2.rb.tt b/railties/lib/rails/generators/rails/app/templates/config/initializers/new_framework_defaults_5_2.rb.tt
new file mode 100644
index 0000000000..ae665b960a
--- /dev/null
+++ b/railties/lib/rails/generators/rails/app/templates/config/initializers/new_framework_defaults_5_2.rb.tt
@@ -0,0 +1,27 @@
+# Be sure to restart your server when you modify this file.
+#
+# This file contains migration options to ease your Rails 5.2 upgrade.
+#
+# Once upgraded flip defaults one by one to migrate to the new default.
+#
+# Read the Guide for Upgrading Ruby on Rails for more info on each option.
+
+# Make Active Record use stable #cache_key alongside new #cache_version method.
+# This is needed for recyclable cache keys.
+# Rails.application.config.active_record.cache_versioning = true
+
+# Use AES-256-GCM authenticated encryption for encrypted cookies.
+# Existing cookies will be converted on read then written with the new scheme.
+# Rails.application.config.action_dispatch.use_authenticated_cookie_encryption = true
+
+# Use AES-256-GCM authenticated encryption as default cipher for encrypting messages
+# instead of AES-256-CBC, when use_authenticated_message_encryption is set to true.
+# Rails.application.config.active_support.use_authenticated_message_encryption = true
+
+# Add default protection from forgery to ActionController::Base instead of in
+# ApplicationController.
+# Rails.application.config.action_controller.default_protect_from_forgery = true
+
+# Store boolean values are in sqlite3 databases as 1 and 0 instead of 't' and
+# 'f' after migrating old data.
+# Rails.application.config.active_record.sqlite3.represent_boolean_as_integer = true
diff --git a/railties/lib/rails/generators/rails/app/templates/config/initializers/session_store.rb.tt b/railties/lib/rails/generators/rails/app/templates/config/initializers/session_store.rb.tt
deleted file mode 100644
index 2bb9b82c61..0000000000
--- a/railties/lib/rails/generators/rails/app/templates/config/initializers/session_store.rb.tt
+++ /dev/null
@@ -1,3 +0,0 @@
-# Be sure to restart your server when you modify this file.
-
-Rails.application.config.session_store :cookie_store, key: <%= "'_#{app_name}_session'" %>
diff --git a/railties/lib/rails/generators/rails/app/templates/config/locales/en.yml b/railties/lib/rails/generators/rails/app/templates/config/locales/en.yml
index 0653957166..decc5a8573 100644
--- a/railties/lib/rails/generators/rails/app/templates/config/locales/en.yml
+++ b/railties/lib/rails/generators/rails/app/templates/config/locales/en.yml
@@ -16,6 +16,16 @@
 #
 # This would use the information in config/locales/es.yml.
 #
+# The following keys must be escaped otherwise they will not be retrieved by
+# the default I18n backend:
+#
+# true, false, on, off, yes, no
+#
+# Instead, surround them with single quotes.
+#
+# en:
+#   'true': 'foo'
+#
 # To learn more, please read the Rails Internationalization guide
 # available at http://guides.rubyonrails.org/i18n.html.
 
diff --git a/railties/lib/rails/generators/rails/app/templates/config/puma.rb b/railties/lib/rails/generators/rails/app/templates/config/puma.rb.tt
index c7f311f811..a5eccf816b 100644
--- a/railties/lib/rails/generators/rails/app/templates/config/puma.rb
+++ b/railties/lib/rails/generators/rails/app/templates/config/puma.rb.tt
@@ -1,13 +1,13 @@
 # Puma can serve each request in a thread from an internal thread pool.
-# The `threads` method setting takes two numbers a minimum and maximum.
+# The `threads` method setting takes two numbers: a minimum and maximum.
 # Any libraries that use thread pools should be configured to match
 # the maximum value specified for Puma. Default is set to 5 threads for minimum
-# and maximum, this matches the default thread size of Active Record.
+# and maximum; this matches the default thread size of Active Record.
 #
-threads_count = ENV.fetch("RAILS_MAX_THREADS") { 5 }.to_i
+threads_count = ENV.fetch("RAILS_MAX_THREADS") { 5 }
 threads threads_count, threads_count
 
-# Specifies the `port` that Puma will listen on to receive requests, default is 3000.
+# Specifies the `port` that Puma will listen on to receive requests; default is 3000.
 #
 port        ENV.fetch("PORT") { 3000 }
 
@@ -26,22 +26,9 @@ environment ENV.fetch("RAILS_ENV") { "development" }
 # Use the `preload_app!` method when specifying a `workers` number.
 # This directive tells Puma to first boot the application and load code
 # before forking the application. This takes advantage of Copy On Write
-# process behavior so workers use less memory. If you use this option
-# you need to make sure to reconnect any threads in the `on_worker_boot`
-# block.
+# process behavior so workers use less memory.
 #
 # preload_app!
 
-# The code in the `on_worker_boot` will be called if you are using
-# clustered mode by specifying a number of `workers`. After each worker
-# process is booted this block will be run, if you are using `preload_app!`
-# option you will want to use this block to reconnect to any threads
-# or connections that may have been created at application boot, Ruby
-# cannot share connections between processes.
-#
-# on_worker_boot do
-#   ActiveRecord::Base.establish_connection if defined?(ActiveRecord)
-# end
-
 # Allow puma to be restarted by `rails restart` command.
 plugin :tmp_restart
diff --git a/railties/lib/rails/generators/rails/app/templates/config/routes.rb b/railties/lib/rails/generators/rails/app/templates/config/routes.rb.tt
index 787824f888..787824f888 100644
--- a/railties/lib/rails/generators/rails/app/templates/config/routes.rb
+++ b/railties/lib/rails/generators/rails/app/templates/config/routes.rb.tt
diff --git a/railties/lib/rails/generators/rails/app/templates/config/spring.rb.tt b/railties/lib/rails/generators/rails/app/templates/config/spring.rb.tt
new file mode 100644
index 0000000000..9fa7863f99
--- /dev/null
+++ b/railties/lib/rails/generators/rails/app/templates/config/spring.rb.tt
@@ -0,0 +1,6 @@
+%w[
+  .ruby-version
+  .rbenv-vars
+  tmp/restart.txt
+  tmp/caching-dev.txt
+].each { |path| Spring.watch(path) }
diff --git a/railties/lib/rails/generators/rails/app/templates/config/storage.yml.tt b/railties/lib/rails/generators/rails/app/templates/config/storage.yml.tt
new file mode 100644
index 0000000000..1c0cde0b09
--- /dev/null
+++ b/railties/lib/rails/generators/rails/app/templates/config/storage.yml.tt
@@ -0,0 +1,35 @@
+test:
+  service: Disk
+  root: <%%= Rails.root.join("tmp/storage") %>
+
+local:
+  service: Disk
+  root: <%%= Rails.root.join("storage") %>
+
+# Use rails credentials:edit to set the AWS secrets (as aws:access_key_id|secret_access_key)
+# amazon:
+#   service: S3
+#   access_key_id: <%%= Rails.application.credentials.dig(:aws, :access_key_id) %>
+#   secret_access_key: <%%= Rails.application.credentials.dig(:aws, :secret_access_key) %>
+#   region: us-east-1
+#   bucket: your_own_bucket
+
+# Remember not to checkin your GCS keyfile to a repository
+# google:
+#   service: GCS
+#   project: your_project
+#   credentials: <%%= Rails.root.join("path/to/gcs.keyfile") %>
+#   bucket: your_own_bucket
+
+# Use rails credentials:edit to set the Azure Storage secret (as azure_storage:storage_access_key)
+# microsoft:
+#   service: AzureStorage
+#   path: your_azure_storage_path
+#   storage_account_name: your_account_name
+#   storage_access_key: <%%= Rails.application.credentials.dig(:azure_storage, :storage_access_key) %>
+#   container: your_container_name
+
+# mirror:
+#   service: Mirror
+#   primary: local
+#   mirrors: [ amazon, google, microsoft ]
diff --git a/railties/lib/rails/generators/rails/app/templates/gitignore b/railties/lib/rails/generators/rails/app/templates/gitignore.tt
index 0e66cc4237..2cd8335aba 100644
--- a/railties/lib/rails/generators/rails/app/templates/gitignore
+++ b/railties/lib/rails/generators/rails/app/templates/gitignore.tt
@@ -21,5 +21,17 @@
 !/tmp/.keep
 <% end -%>
 
-# Ignore Byebug command history file.
+<% unless skip_active_storage? -%>
+# Ignore uploaded files in development
+/storage/*
+
+<% end -%>
+<% unless options.skip_yarn? -%>
+/node_modules
+/yarn-error.log
+
+<% end -%>
+<% unless options.api? -%>
+/public/assets
+<% end -%>
 .byebug_history
diff --git a/railties/lib/rails/generators/rails/app/templates/package.json.tt b/railties/lib/rails/generators/rails/app/templates/package.json.tt
new file mode 100644
index 0000000000..46db57dcbe
--- /dev/null
+++ b/railties/lib/rails/generators/rails/app/templates/package.json.tt
@@ -0,0 +1,5 @@
+{
+  "name": "<%= app_name %>",
+  "private": true,
+  "dependencies": {}
+}
diff --git a/railties/lib/rails/generators/rails/app/templates/public/404.html b/railties/lib/rails/generators/rails/app/templates/public/404.html
index b612547fc2..2be3af26fc 100644
--- a/railties/lib/rails/generators/rails/app/templates/public/404.html
+++ b/railties/lib/rails/generators/rails/app/templates/public/404.html
@@ -4,7 +4,7 @@
   <title>The page you were looking for doesn't exist (404)</title>
   <meta name="viewport" content="width=device-width,initial-scale=1">
   <style>
-  body {
+  .rails-default-error-page {
     background-color: #EFEFEF;
     color: #2E2F30;
     text-align: center;
@@ -12,13 +12,13 @@
     margin: 0;
   }
 
-  div.dialog {
+  .rails-default-error-page div.dialog {
     width: 95%;
     max-width: 33em;
     margin: 4em auto 0;
   }
 
-  div.dialog > div {
+  .rails-default-error-page div.dialog > div {
     border: 1px solid #CCC;
     border-right-color: #999;
     border-left-color: #999;
@@ -31,13 +31,13 @@
     box-shadow: 0 3px 8px rgba(50, 50, 50, 0.17);
   }
 
-  h1 {
+  .rails-default-error-page h1 {
     font-size: 100%;
     color: #730E15;
     line-height: 1.5em;
   }
 
-  div.dialog > p {
+  .rails-default-error-page div.dialog > p {
     margin: 0 0 1em;
     padding: 1em;
     background-color: #F7F7F7;
@@ -54,7 +54,7 @@
   </style>
 </head>
 
-<body>
+<body class="rails-default-error-page">
   <!-- This file lives in public/404.html -->
   <div class="dialog">
     <div>
diff --git a/railties/lib/rails/generators/rails/app/templates/public/422.html b/railties/lib/rails/generators/rails/app/templates/public/422.html
index a21f82b3bd..c08eac0d1d 100644
--- a/railties/lib/rails/generators/rails/app/templates/public/422.html
+++ b/railties/lib/rails/generators/rails/app/templates/public/422.html
@@ -4,7 +4,7 @@
   <title>The change you wanted was rejected (422)</title>
   <meta name="viewport" content="width=device-width,initial-scale=1">
   <style>
-  body {
+  .rails-default-error-page {
     background-color: #EFEFEF;
     color: #2E2F30;
     text-align: center;
@@ -12,13 +12,13 @@
     margin: 0;
   }
 
-  div.dialog {
+  .rails-default-error-page div.dialog {
     width: 95%;
     max-width: 33em;
     margin: 4em auto 0;
   }
 
-  div.dialog > div {
+  .rails-default-error-page div.dialog > div {
     border: 1px solid #CCC;
     border-right-color: #999;
     border-left-color: #999;
@@ -31,13 +31,13 @@
     box-shadow: 0 3px 8px rgba(50, 50, 50, 0.17);
   }
 
-  h1 {
+  .rails-default-error-page h1 {
     font-size: 100%;
     color: #730E15;
     line-height: 1.5em;
   }
 
-  div.dialog > p {
+  .rails-default-error-page div.dialog > p {
     margin: 0 0 1em;
     padding: 1em;
     background-color: #F7F7F7;
@@ -54,7 +54,7 @@
   </style>
 </head>
 
-<body>
+<body class="rails-default-error-page">
   <!-- This file lives in public/422.html -->
   <div class="dialog">
     <div>
diff --git a/railties/lib/rails/generators/rails/app/templates/public/500.html b/railties/lib/rails/generators/rails/app/templates/public/500.html
index 061abc587d..78a030af22 100644
--- a/railties/lib/rails/generators/rails/app/templates/public/500.html
+++ b/railties/lib/rails/generators/rails/app/templates/public/500.html
@@ -4,7 +4,7 @@
   <title>We're sorry, but something went wrong (500)</title>
   <meta name="viewport" content="width=device-width,initial-scale=1">
   <style>
-  body {
+  .rails-default-error-page {
     background-color: #EFEFEF;
     color: #2E2F30;
     text-align: center;
@@ -12,13 +12,13 @@
     margin: 0;
   }
 
-  div.dialog {
+  .rails-default-error-page div.dialog {
     width: 95%;
     max-width: 33em;
     margin: 4em auto 0;
   }
 
-  div.dialog > div {
+  .rails-default-error-page div.dialog > div {
     border: 1px solid #CCC;
     border-right-color: #999;
     border-left-color: #999;
@@ -31,13 +31,13 @@
     box-shadow: 0 3px 8px rgba(50, 50, 50, 0.17);
   }
 
-  h1 {
+  .rails-default-error-page h1 {
     font-size: 100%;
     color: #730E15;
     line-height: 1.5em;
   }
 
-  div.dialog > p {
+  .rails-default-error-page div.dialog > p {
     margin: 0 0 1em;
     padding: 1em;
     background-color: #F7F7F7;
@@ -54,7 +54,7 @@
   </style>
 </head>
 
-<body>
+<body class="rails-default-error-page">
   <!-- This file lives in public/500.html -->
   <div class="dialog">
     <div>
diff --git a/railties/lib/rails/generators/rails/app/templates/public/robots.txt b/railties/lib/rails/generators/rails/app/templates/public/robots.txt
index 3c9c7c01f3..37b576a4a0 100644
--- a/railties/lib/rails/generators/rails/app/templates/public/robots.txt
+++ b/railties/lib/rails/generators/rails/app/templates/public/robots.txt
@@ -1,5 +1 @@
 # See http://www.robotstxt.org/robotstxt.html for documentation on how to use the robots.txt file
-#
-# To ban all spiders from the entire site uncomment the next two lines:
-# User-agent: *
-# Disallow: /
diff --git a/railties/lib/rails/generators/rails/app/templates/ruby-version.tt b/railties/lib/rails/generators/rails/app/templates/ruby-version.tt
new file mode 100644
index 0000000000..c444f33b0f
--- /dev/null
+++ b/railties/lib/rails/generators/rails/app/templates/ruby-version.tt
@@ -0,0 +1 @@
+<%= RUBY_VERSION -%>
diff --git a/railties/lib/rails/generators/rails/app/templates/test/application_system_test_case.rb.tt b/railties/lib/rails/generators/rails/app/templates/test/application_system_test_case.rb.tt
new file mode 100644
index 0000000000..d19212abd5
--- /dev/null
+++ b/railties/lib/rails/generators/rails/app/templates/test/application_system_test_case.rb.tt
@@ -0,0 +1,5 @@
+require "test_helper"
+
+class ApplicationSystemTestCase < ActionDispatch::SystemTestCase
+  driven_by :selenium, using: :chrome, screen_size: [1400, 1400]
+end
diff --git a/railties/lib/rails/generators/rails/app/templates/test/test_helper.rb b/railties/lib/rails/generators/rails/app/templates/test/test_helper.rb.tt
index 87b8fe3516..52d68cc77c 100644
--- a/railties/lib/rails/generators/rails/app/templates/test/test_helper.rb
+++ b/railties/lib/rails/generators/rails/app/templates/test/test_helper.rb.tt
@@ -1,5 +1,5 @@
 ENV['RAILS_ENV'] ||= 'test'
-require File.expand_path('../../config/environment', __FILE__)
+require_relative '../config/environment'
 require 'rails/test_help'
 
 class ActiveSupport::TestCase
diff --git a/railties/lib/rails/generators/rails/application_record/application_record_generator.rb b/railties/lib/rails/generators/rails/application_record/application_record_generator.rb
new file mode 100644
index 0000000000..f6b6e76b1d
--- /dev/null
+++ b/railties/lib/rails/generators/rails/application_record/application_record_generator.rb
@@ -0,0 +1,9 @@
+# frozen_string_literal: true
+
+module Rails
+  module Generators
+    class ApplicationRecordGenerator < Base # :nodoc:
+      hook_for :orm, required: true, desc: "ORM to be invoked"
+    end
+  end
+end
diff --git a/railties/lib/rails/generators/rails/assets/assets_generator.rb b/railties/lib/rails/generators/rails/assets/assets_generator.rb
index 6f4b86e708..ffb695a1f3 100644
--- a/railties/lib/rails/generators/rails/assets/assets_generator.rb
+++ b/railties/lib/rails/generators/rails/assets/assets_generator.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module Rails
   module Generators
     class AssetsGenerator < NamedBase # :nodoc:
@@ -7,19 +9,19 @@ module Rails
       class_option :javascript_engine, desc: "Engine for JavaScripts"
       class_option :stylesheet_engine, desc: "Engine for Stylesheets"
 
-      protected
+      private
 
-      def asset_name
-        file_name
-      end
+        def asset_name
+          file_name
+        end
 
-      hook_for :javascript_engine do |javascript_engine|
-        invoke javascript_engine, [name] if options[:javascripts]
-      end
+        hook_for :javascript_engine do |javascript_engine|
+          invoke javascript_engine, [name] if options[:javascripts]
+        end
 
-      hook_for :stylesheet_engine do |stylesheet_engine|
-        invoke stylesheet_engine, [name] if options[:stylesheets]
-      end
+        hook_for :stylesheet_engine do |stylesheet_engine|
+          invoke stylesheet_engine, [name] if options[:stylesheets]
+        end
     end
   end
 end
diff --git a/railties/lib/rails/generators/rails/assets/templates/stylesheet.css b/railties/lib/rails/generators/rails/assets/templates/stylesheet.css
index 7594abf268..afad32db02 100644
--- a/railties/lib/rails/generators/rails/assets/templates/stylesheet.css
+++ b/railties/lib/rails/generators/rails/assets/templates/stylesheet.css
@@ -1,4 +1,4 @@
-/* 
+/*
   Place all the styles related to the matching controller here.
   They will automatically be included in application.css.
 */
diff --git a/railties/lib/rails/generators/rails/controller/controller_generator.rb b/railties/lib/rails/generators/rails/controller/controller_generator.rb
index 6c583e5811..6d45d6e8f8 100644
--- a/railties/lib/rails/generators/rails/controller/controller_generator.rb
+++ b/railties/lib/rails/generators/rails/controller/controller_generator.rb
@@ -1,22 +1,22 @@
+# frozen_string_literal: true
+
 module Rails
   module Generators
     class ControllerGenerator < NamedBase # :nodoc:
       argument :actions, type: :array, default: [], banner: "action action"
       class_option :skip_routes, type: :boolean, desc: "Don't add routes to config/routes.rb."
+      class_option :helper, type: :boolean
+      class_option :assets, type: :boolean
 
       check_class_collision suffix: "Controller"
 
       def create_controller_files
-        template 'controller.rb', File.join('app/controllers', class_path, "#{file_name}_controller.rb")
+        template "controller.rb", File.join("app/controllers", class_path, "#{file_name}_controller.rb")
       end
 
       def add_routes
-        unless options[:skip_routes]
-          actions.reverse_each do |action|
-            # route prepends two spaces onto the front of the string that is passed, this corrects that.
-            route generate_routing_code(action)[2..-1]
-          end
-        end
+        return if options[:skip_routes]
+        route generate_routing_code
       end
 
       hook_for :template_engine, :test_framework, :helper, :assets
@@ -24,35 +24,42 @@ module Rails
       private
 
         # This method creates nested route entry for namespaced resources.
-        # For eg. rails g controller foo/bar/baz index
+        # For eg. rails g controller foo/bar/baz index show
         # Will generate -
         # namespace :foo do
         #   namespace :bar do
         #     get 'baz/index'
+        #     get 'baz/show'
         #   end
         # end
-        def generate_routing_code(action)
-          depth = regular_class_path.length
+        def generate_routing_code
+          depth = 0
+          lines = []
+
           # Create 'namespace' ladder
           # namespace :foo do
           #   namespace :bar do
-          namespace_ladder = regular_class_path.each_with_index.map do |ns, i|
-            indent("  namespace :#{ns} do\n", i * 2)
-          end.join
+          regular_class_path.each do |ns|
+            lines << indent("namespace :#{ns} do\n", depth * 2)
+            depth += 1
+          end
 
           # Create route
           #     get 'baz/index'
-          route = indent(%{  get '#{file_name}/#{action}'\n}, depth * 2)
+          #     get 'baz/show'
+          actions.each do |action|
+            lines << indent(%{get '#{file_name}/#{action}'\n}, depth * 2)
+          end
 
           # Create `end` ladder
           #   end
           # end
-          end_ladder = (1..depth).reverse_each.map do |i|
-            indent("end\n", i * 2)
-          end.join
+          until depth.zero?
+            depth -= 1
+            lines << indent("end\n", depth * 2)
+          end
 
-          # Combine the 3 parts to generate complete route entry
-          namespace_ladder + route + end_ladder
+          lines.join
         end
     end
   end
diff --git a/railties/lib/rails/generators/rails/controller/templates/controller.rb b/railties/lib/rails/generators/rails/controller/templates/controller.rb.tt
index 633e0b3177..633e0b3177 100644
--- a/railties/lib/rails/generators/rails/controller/templates/controller.rb
+++ b/railties/lib/rails/generators/rails/controller/templates/controller.rb.tt
diff --git a/railties/lib/rails/generators/rails/credentials/credentials_generator.rb b/railties/lib/rails/generators/rails/credentials/credentials_generator.rb
new file mode 100644
index 0000000000..9103b1122e
--- /dev/null
+++ b/railties/lib/rails/generators/rails/credentials/credentials_generator.rb
@@ -0,0 +1,51 @@
+# frozen_string_literal: true
+
+require "rails/generators/base"
+require "rails/generators/rails/master_key/master_key_generator"
+require "active_support/encrypted_configuration"
+
+module Rails
+  module Generators
+    class CredentialsGenerator < Base
+      def add_credentials_file
+        unless credentials.content_path.exist?
+          template = credentials_template
+
+          say "Adding #{credentials.content_path} to store encrypted credentials."
+          say ""
+          say "The following content has been encrypted with the Rails master key:"
+          say ""
+          say template, :on_green
+          say ""
+
+          add_credentials_file_silently(template)
+
+          say "You can edit encrypted credentials with `bin/rails credentials:edit`."
+          say ""
+        end
+      end
+
+      def add_credentials_file_silently(template = nil)
+        unless credentials.content_path.exist?
+          credentials.write(credentials_template)
+        end
+      end
+
+      private
+        def credentials
+          ActiveSupport::EncryptedConfiguration.new(
+            config_path: "config/credentials.yml.enc",
+            key_path: "config/master.key",
+            env_key: "RAILS_MASTER_KEY",
+            raise_if_missing_key: true
+          )
+        end
+
+        def credentials_template
+          "# aws:\n#  access_key_id: 123\n#  secret_access_key: 345\n\n" +
+          "# Used as the base secret for all MessageVerifiers in Rails, including the one protecting cookies.\n" +
+          "secret_key_base: #{SecureRandom.hex(64)}"
+        end
+    end
+  end
+end
diff --git a/railties/lib/rails/generators/rails/encrypted_file/encrypted_file_generator.rb b/railties/lib/rails/generators/rails/encrypted_file/encrypted_file_generator.rb
new file mode 100644
index 0000000000..4ce2fc1d86
--- /dev/null
+++ b/railties/lib/rails/generators/rails/encrypted_file/encrypted_file_generator.rb
@@ -0,0 +1,38 @@
+# frozen_string_literal: true
+
+require "rails/generators/base"
+require "active_support/encrypted_file"
+
+module Rails
+  module Generators
+    class EncryptedFileGenerator < Base
+      def add_encrypted_file(file_path, key_path)
+        unless File.exist?(file_path)
+          say "Adding #{file_path} to store encrypted content."
+          say ""
+          say "The following content has been encrypted with the encryption key:"
+          say ""
+          say template, :on_green
+          say ""
+
+          add_encrypted_file_silently(file_path, key_path)
+
+          say "You can edit encrypted file with `bin/rails encrypted:edit #{file_path}`."
+          say ""
+        end
+      end
+
+      def add_encrypted_file_silently(file_path, key_path, template = encrypted_file_template)
+        unless File.exist?(file_path)
+          setup = { content_path: file_path, key_path: key_path, env_key: "RAILS_MASTER_KEY", raise_if_missing_key: true }
+          ActiveSupport::EncryptedFile.new(setup).write(template)
+        end
+      end
+
+      private
+        def encrypted_file_template
+          "# aws:\n#  access_key_id: 123\n#  secret_access_key: 345\n\n"
+        end
+    end
+  end
+end
diff --git a/railties/lib/rails/generators/rails/encryption_key_file/encryption_key_file_generator.rb b/railties/lib/rails/generators/rails/encryption_key_file/encryption_key_file_generator.rb
new file mode 100644
index 0000000000..a396a9661f
--- /dev/null
+++ b/railties/lib/rails/generators/rails/encryption_key_file/encryption_key_file_generator.rb
@@ -0,0 +1,57 @@
+# frozen_string_literal: true
+
+require "pathname"
+require "rails/generators/base"
+require "active_support/encrypted_file"
+
+module Rails
+  module Generators
+    class EncryptionKeyFileGenerator < Base
+      def add_key_file(key_path)
+        key_path = Pathname.new(key_path)
+
+        unless key_path.exist?
+          key = ActiveSupport::EncryptedFile.generate_key
+
+          log "Adding #{key_path} to store the encryption key: #{key}"
+          log ""
+          log "Save this in a password manager your team can access."
+          log ""
+          log "If you lose the key, no one, including you, can access anything encrypted with it."
+
+          log ""
+          add_key_file_silently(key_path, key)
+          log ""
+        end
+      end
+
+      def add_key_file_silently(key_path, key = nil)
+        create_file key_path, key || ActiveSupport::EncryptedFile.generate_key
+      end
+
+      def ignore_key_file(key_path, ignore: key_ignore(key_path))
+        if File.exist?(".gitignore")
+          unless File.read(".gitignore").include?(ignore)
+            log "Ignoring #{key_path} so it won't end up in Git history:"
+            log ""
+            append_to_file ".gitignore", ignore
+            log ""
+          end
+        else
+          log "IMPORTANT: Don't commit #{key_path}. Add this to your ignore file:"
+          log ignore, :on_green
+          log ""
+        end
+      end
+
+      def ignore_key_file_silently(key_path, ignore: key_ignore(key_path))
+        append_to_file ".gitignore", ignore if File.exist?(".gitignore")
+      end
+
+      private
+        def key_ignore(key_path)
+          [ "", "/#{key_path}", "" ].join("\n")
+        end
+    end
+  end
+end
diff --git a/railties/lib/rails/generators/rails/generator/generator_generator.rb b/railties/lib/rails/generators/rails/generator/generator_generator.rb
index 15d88f06ac..747acd68d1 100644
--- a/railties/lib/rails/generators/rails/generator/generator_generator.rb
+++ b/railties/lib/rails/generators/rails/generator/generator_generator.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module Rails
   module Generators
     class GeneratorGenerator < NamedBase # :nodoc:
@@ -7,12 +9,12 @@ module Rails
                                desc: "Namespace generator under lib/generators/name"
 
       def create_generator_files
-        directory '.', generator_dir
+        directory ".", generator_dir
       end
 
       hook_for :test_framework
 
-      protected
+      private
 
         def generator_dir
           if options[:namespace]
@@ -21,7 +23,6 @@ module Rails
             File.join("lib", "generators", regular_class_path)
           end
         end
-
     end
   end
 end
diff --git a/railties/lib/rails/generators/rails/generator/templates/%file_name%_generator.rb.tt b/railties/lib/rails/generators/rails/generator/templates/%file_name%_generator.rb.tt
index d0575772bc..178d5c3f9f 100644
--- a/railties/lib/rails/generators/rails/generator/templates/%file_name%_generator.rb.tt
+++ b/railties/lib/rails/generators/rails/generator/templates/%file_name%_generator.rb.tt
@@ -1,3 +1,3 @@
 class <%= class_name %>Generator < Rails::Generators::NamedBase
-  source_root File.expand_path('../templates', __FILE__)
+  source_root File.expand_path('templates', __dir__)
 end
diff --git a/railties/lib/rails/generators/rails/helper/helper_generator.rb b/railties/lib/rails/generators/rails/helper/helper_generator.rb
index 5ff38e4111..3837c10ca0 100644
--- a/railties/lib/rails/generators/rails/helper/helper_generator.rb
+++ b/railties/lib/rails/generators/rails/helper/helper_generator.rb
@@ -1,10 +1,12 @@
+# frozen_string_literal: true
+
 module Rails
   module Generators
     class HelperGenerator < NamedBase # :nodoc:
       check_class_collision suffix: "Helper"
 
       def create_helper_files
-        template 'helper.rb', File.join('app/helpers', class_path, "#{file_name}_helper.rb")
+        template "helper.rb", File.join("app/helpers", class_path, "#{file_name}_helper.rb")
       end
 
       hook_for :test_framework
diff --git a/railties/lib/rails/generators/rails/helper/templates/helper.rb b/railties/lib/rails/generators/rails/helper/templates/helper.rb.tt
index b4173151b4..b4173151b4 100644
--- a/railties/lib/rails/generators/rails/helper/templates/helper.rb
+++ b/railties/lib/rails/generators/rails/helper/templates/helper.rb.tt
diff --git a/railties/lib/rails/generators/rails/integration_test/integration_test_generator.rb b/railties/lib/rails/generators/rails/integration_test/integration_test_generator.rb
index 70770ddcb8..975dd8b90c 100644
--- a/railties/lib/rails/generators/rails/integration_test/integration_test_generator.rb
+++ b/railties/lib/rails/generators/rails/integration_test/integration_test_generator.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module Rails
   module Generators
     class IntegrationTestGenerator < NamedBase # :nodoc:
diff --git a/railties/lib/rails/generators/rails/master_key/master_key_generator.rb b/railties/lib/rails/generators/rails/master_key/master_key_generator.rb
new file mode 100644
index 0000000000..7f57340c11
--- /dev/null
+++ b/railties/lib/rails/generators/rails/master_key/master_key_generator.rb
@@ -0,0 +1,51 @@
+# frozen_string_literal: true
+
+require "pathname"
+require "rails/generators/base"
+require "rails/generators/rails/encryption_key_file/encryption_key_file_generator"
+require "active_support/encrypted_file"
+
+module Rails
+  module Generators
+    class MasterKeyGenerator < Base
+      MASTER_KEY_PATH = Pathname.new("config/master.key")
+
+      def add_master_key_file
+        unless MASTER_KEY_PATH.exist?
+          key = ActiveSupport::EncryptedFile.generate_key
+
+          log "Adding #{MASTER_KEY_PATH} to store the master encryption key: #{key}"
+          log ""
+          log "Save this in a password manager your team can access."
+          log ""
+          log "If you lose the key, no one, including you, can access anything encrypted with it."
+
+          log ""
+          add_master_key_file_silently(key)
+          log ""
+        end
+      end
+
+      def add_master_key_file_silently(key = nil)
+        key_file_generator.add_key_file_silently(MASTER_KEY_PATH, key)
+      end
+
+      def ignore_master_key_file
+        key_file_generator.ignore_key_file(MASTER_KEY_PATH, ignore: key_ignore)
+      end
+
+      def ignore_master_key_file_silently
+        key_file_generator.ignore_key_file_silently(MASTER_KEY_PATH, ignore: key_ignore)
+      end
+
+      private
+        def key_file_generator
+          EncryptionKeyFileGenerator.new([], options)
+        end
+
+        def key_ignore
+          [ "", "# Ignore master key for decrypting credentials and more.", "/#{MASTER_KEY_PATH}", "" ].join("\n")
+        end
+    end
+  end
+end
diff --git a/railties/lib/rails/generators/rails/migration/migration_generator.rb b/railties/lib/rails/generators/rails/migration/migration_generator.rb
index fca2a8fef4..c331c135e3 100644
--- a/railties/lib/rails/generators/rails/migration/migration_generator.rb
+++ b/railties/lib/rails/generators/rails/migration/migration_generator.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module Rails
   module Generators
     class MigrationGenerator < NamedBase # :nodoc:
diff --git a/railties/lib/rails/generators/rails/model/model_generator.rb b/railties/lib/rails/generators/rails/model/model_generator.rb
index ec78fd855d..de4de2cae2 100644
--- a/railties/lib/rails/generators/rails/model/model_generator.rb
+++ b/railties/lib/rails/generators/rails/model/model_generator.rb
@@ -1,4 +1,6 @@
-require 'rails/generators/model_helpers'
+# frozen_string_literal: true
+
+require "rails/generators/model_helpers"
 
 module Rails
   module Generators
diff --git a/railties/lib/rails/generators/rails/plugin/plugin_generator.rb b/railties/lib/rails/generators/rails/plugin/plugin_generator.rb
index 56efd35a95..a83c911806 100644
--- a/railties/lib/rails/generators/rails/plugin/plugin_generator.rb
+++ b/railties/lib/rails/generators/rails/plugin/plugin_generator.rb
@@ -1,6 +1,7 @@
-require 'active_support/core_ext/hash/slice'
+# frozen_string_literal: true
+
 require "rails/generators/rails/app/app_generator"
-require 'date'
+require "date"
 
 module Rails
   # The plugin builder allows you to override elements of the plugin
@@ -18,20 +19,20 @@ module Rails
     def app
       if mountable?
         if api?
-          directory 'app', exclude_pattern: %r{app/(views|helpers)}
+          directory "app", exclude_pattern: %r{app/(views|helpers)}
         else
-          directory 'app'
+          directory "app"
           empty_directory_with_keep_file "app/assets/images/#{namespaced_name}"
         end
       elsif full?
-        empty_directory_with_keep_file 'app/models'
-        empty_directory_with_keep_file 'app/controllers'
-        empty_directory_with_keep_file 'app/mailers'
+        empty_directory_with_keep_file "app/models"
+        empty_directory_with_keep_file "app/controllers"
+        empty_directory_with_keep_file "app/mailers"
 
         unless api?
           empty_directory_with_keep_file "app/assets/images/#{namespaced_name}"
-          empty_directory_with_keep_file 'app/helpers'
-          empty_directory_with_keep_file 'app/views'
+          empty_directory_with_keep_file "app/helpers"
+          empty_directory_with_keep_file "app/views"
         end
       end
     end
@@ -60,7 +61,12 @@ module Rails
       template "lib/%namespaced_name%.rb"
       template "lib/tasks/%namespaced_name%_tasks.rake"
       template "lib/%namespaced_name%/version.rb"
-      template "lib/%namespaced_name%/engine.rb" if engine?
+
+      if engine?
+        template "lib/%namespaced_name%/engine.rb"
+      else
+        template "lib/%namespaced_name%/railtie.rb"
+      end
     end
 
     def config
@@ -71,8 +77,8 @@ module Rails
       template "test/test_helper.rb"
       template "test/%namespaced_name%_test.rb"
       append_file "Rakefile", <<-EOF
-#{rakefile_test_tasks}
 
+#{rakefile_test_tasks}
 task default: :test
       EOF
       if engine?
@@ -81,16 +87,18 @@ task default: :test
     end
 
     PASSTHROUGH_OPTIONS = [
-      :skip_active_record, :skip_action_mailer, :skip_javascript, :database,
-      :javascript, :quiet, :pretend, :force, :skip
+      :skip_active_record, :skip_active_storage, :skip_action_mailer, :skip_javascript, :skip_action_cable, :skip_sprockets, :database,
+      :javascript, :skip_yarn, :api, :quiet, :pretend, :skip
     ]
 
     def generate_test_dummy(force = false)
-      opts = (options || {}).slice(*PASSTHROUGH_OPTIONS)
+      opts = (options.dup || {}).keep_if { |k, _| PASSTHROUGH_OPTIONS.map(&:to_s).include?(k) }
       opts[:force] = force
       opts[:skip_bundle] = true
-      opts[:api] = options.api?
       opts[:skip_listen] = true
+      opts[:skip_git] = true
+      opts[:skip_turbolinks] = true
+      opts[:dummy_app] = true
 
       invoke Rails::Generators::AppGenerator,
         [ File.expand_path(dummy_path, destination_root) ], opts
@@ -112,9 +120,7 @@ task default: :test
 
     def test_dummy_clean
       inside dummy_path do
-        remove_file ".gitignore"
         remove_file "db/seeds.rb"
-        remove_file "doc"
         remove_file "Gemfile"
         remove_file "lib/tasks"
         remove_file "public/robots.txt"
@@ -149,7 +155,7 @@ task default: :test
     end
 
     def bin(force = false)
-      bin_file = engine? ? 'bin/rails.tt' : 'bin/test.tt'
+      bin_file = engine? ? "bin/rails.tt" : "bin/test.tt"
       template bin_file, force: force do |content|
         "#{shebang}\n" + content
       end
@@ -161,7 +167,7 @@ task default: :test
 
       gemfile_in_app_path = File.join(rails_app_path, "Gemfile")
       if File.exist? gemfile_in_app_path
-        entry = "gem '#{name}', path: '#{relative_path}'"
+        entry = "\ngem '#{name}', path: '#{relative_path}'"
         append_file gemfile_in_app_path, entry
       end
     end
@@ -186,7 +192,7 @@ task default: :test
                                   desc: "Skip gemspec file"
 
       class_option :skip_gemfile_entry, type: :boolean, default: false,
-                                        desc: "If creating plugin in application's directory " +
+                                        desc: "If creating plugin in application's directory " \
                                                  "skip adding entry to Gemfile"
 
       class_option :api,          type: :boolean, default: false,
@@ -195,10 +201,6 @@ task default: :test
       def initialize(*args)
         @dummy_path = nil
         super
-
-        unless plugin_path
-          raise Error, "Plugin name should be provided in arguments. For details run: rails plugin new --help"
-        end
       end
 
       public_task :set_default_accessors!
@@ -258,9 +260,13 @@ task default: :test
         build(:leftovers)
       end
 
-      public_task :apply_rails_template, :run_bundle
+      public_task :apply_rails_template
 
       def run_after_bundle_callbacks
+        unless @after_bundle_callbacks.empty?
+          ActiveSupport::Deprecation.warn("`after_bundle` is deprecated and will be removed in the next version of Rails. ")
+        end
+
         @after_bundle_callbacks.each do |callback|
           callback.call
         end
@@ -270,8 +276,8 @@ task default: :test
         @name ||= begin
           # same as ActiveSupport::Inflector#underscore except not replacing '-'
           underscored = original_name.dup
-          underscored.gsub!(/([A-Z]+)([A-Z][a-z])/,'\1_\2')
-          underscored.gsub!(/([a-z\d])([A-Z])/,'\1_\2')
+          underscored.gsub!(/([A-Z]+)([A-Z][a-z])/, '\1_\2')
+          underscored.gsub!(/([a-z\d])([A-Z])/, '\1_\2')
           underscored.downcase!
 
           underscored
@@ -283,10 +289,10 @@ task default: :test
       end
 
       def namespaced_name
-        @namespaced_name ||= name.gsub('-', '/')
+        @namespaced_name ||= name.tr("-", "/")
       end
 
-    protected
+    private
 
       def create_dummy_app(path = nil)
         dummy_path(path) if path
@@ -304,7 +310,7 @@ task default: :test
       end
 
       def engine?
-        full? || mountable?
+        full? || mountable? || options[:engine]
       end
 
       def full?
@@ -320,7 +326,7 @@ task default: :test
       end
 
       def with_dummy_app?
-        options[:skip_test].blank? || options[:dummy_path] != 'test/dummy'
+        options[:skip_test].blank? || options[:dummy_path] != "test/dummy"
       end
 
       def api?
@@ -328,7 +334,7 @@ task default: :test
       end
 
       def self.banner
-        "rails plugin new #{self.arguments.map(&:usage).join(' ')} [options]"
+        "rails plugin new #{arguments.map(&:usage).join(' ')} [options]"
       end
 
       def original_name
@@ -340,7 +346,7 @@ task default: :test
       end
 
       def wrap_in_modules(unwrapped_code)
-        unwrapped_code = "#{unwrapped_code}".strip.gsub(/\s$\n/, '')
+        unwrapped_code = "#{unwrapped_code}".strip.gsub(/\s$\n/, "")
         modules.reverse.inject(unwrapped_code) do |content, mod|
           str = "module #{mod}\n"
           str += content.lines.map { |line| "  #{line}" }.join
@@ -357,7 +363,7 @@ task default: :test
       end
 
       def camelized
-        @camelized ||= name.gsub(/\W/, '_').squeeze('_').camelize
+        @camelized ||= name.gsub(/\W/, "_").squeeze("_").camelize
       end
 
       def author
@@ -415,7 +421,6 @@ task default: :test
 require 'rake/testtask'
 
 Rake::TestTask.new(:test) do |t|
-  t.libs << 'lib'
   t.libs << 'test'
   t.pattern = 'test/**/*_test.rb'
   t.verbose = false
@@ -437,12 +442,12 @@ end
       end
 
       def inside_application?
-        rails_app_path && app_path =~ /^#{rails_app_path}/
+        rails_app_path && destination_root.start_with?(rails_app_path.to_s)
       end
 
       def relative_path
         return unless inside_application?
-        app_path.sub(/^#{rails_app_path}\//, '')
+        app_path.sub(/^#{rails_app_path}\//, "")
       end
     end
   end
diff --git a/railties/lib/rails/generators/rails/plugin/templates/%name%.gemspec b/railties/lib/rails/generators/rails/plugin/templates/%name%.gemspec.tt
index d84d1aabdb..9a8c4bf098 100644
--- a/railties/lib/rails/generators/rails/plugin/templates/%name%.gemspec
+++ b/railties/lib/rails/generators/rails/plugin/templates/%name%.gemspec.tt
@@ -1,4 +1,4 @@
-$:.push File.expand_path("../lib", __FILE__)
+$:.push File.expand_path("lib", __dir__)
 
 # Maintain your gem's version:
 require "<%= namespaced_name %>/version"
diff --git a/railties/lib/rails/generators/rails/plugin/templates/Gemfile b/railties/lib/rails/generators/rails/plugin/templates/Gemfile.tt
index 22a4548ff2..290259b4db 100644
--- a/railties/lib/rails/generators/rails/plugin/templates/Gemfile
+++ b/railties/lib/rails/generators/rails/plugin/templates/Gemfile.tt
@@ -1,4 +1,5 @@
 source 'https://rubygems.org'
+git_source(:github) { |repo| "https://github.com/#{repo}.git" }
 
 <% if options[:skip_gemspec] -%>
 <%= '# ' if options.dev? || options.edge? -%>gem 'rails', '<%= Array(rails_version_specifier).join("', '") %>'
diff --git a/railties/lib/rails/generators/rails/plugin/templates/MIT-LICENSE b/railties/lib/rails/generators/rails/plugin/templates/MIT-LICENSE.tt
index ff2fb3ba4e..ff2fb3ba4e 100644
--- a/railties/lib/rails/generators/rails/plugin/templates/MIT-LICENSE
+++ b/railties/lib/rails/generators/rails/plugin/templates/MIT-LICENSE.tt
diff --git a/railties/lib/rails/generators/rails/plugin/templates/README.md b/railties/lib/rails/generators/rails/plugin/templates/README.md.tt
index 9d2b74416e..1632409bea 100644
--- a/railties/lib/rails/generators/rails/plugin/templates/README.md
+++ b/railties/lib/rails/generators/rails/plugin/templates/README.md.tt
@@ -25,4 +25,4 @@ $ gem install <%= name %>
 Contribution directions go here.
 
 ## License
-The gem is available as open source under the terms of the [MIT License](http://opensource.org/licenses/MIT).
+The gem is available as open source under the terms of the [MIT License](https://opensource.org/licenses/MIT).
diff --git a/railties/lib/rails/generators/rails/plugin/templates/Rakefile b/railties/lib/rails/generators/rails/plugin/templates/Rakefile.tt
index 383d2fb2d1..f3efe21cf1 100644
--- a/railties/lib/rails/generators/rails/plugin/templates/Rakefile
+++ b/railties/lib/rails/generators/rails/plugin/templates/Rakefile.tt
@@ -13,17 +13,16 @@ RDoc::Task.new(:rdoc) do |rdoc|
   rdoc.rdoc_files.include('README.md')
   rdoc.rdoc_files.include('lib/**/*.rb')
 end
-
 <% if engine? && !options[:skip_active_record] && with_dummy_app? -%>
-APP_RAKEFILE = File.expand_path("../<%= dummy_path -%>/Rakefile", __FILE__)
-load 'rails/tasks/engine.rake'
-<% end %>
 
+APP_RAKEFILE = File.expand_path("<%= dummy_path -%>/Rakefile", __dir__)
+load 'rails/tasks/engine.rake'
+<% end -%>
 <% if engine? -%>
-load 'rails/tasks/statistics.rake'
-<% end %>
 
+load 'rails/tasks/statistics.rake'
+<% end -%>
 <% unless options[:skip_gemspec] -%>
 
 require 'bundler/gem_tasks'
-<% end %>
+<% end -%>
diff --git a/railties/lib/rails/generators/rails/plugin/templates/bin/rails.tt b/railties/lib/rails/generators/rails/plugin/templates/bin/rails.tt
index 56e7925c6b..b3264509fc 100644
--- a/railties/lib/rails/generators/rails/plugin/templates/bin/rails.tt
+++ b/railties/lib/rails/generators/rails/plugin/templates/bin/rails.tt
@@ -1,12 +1,30 @@
 # This command will automatically be run when you run "rails" with Rails gems
 # installed from the root of your application.
 
-ENGINE_ROOT = File.expand_path('../..', __FILE__)
-ENGINE_PATH = File.expand_path('../../lib/<%= namespaced_name -%>/engine', __FILE__)
+ENGINE_ROOT = File.expand_path('..', __dir__)
+ENGINE_PATH = File.expand_path('../lib/<%= namespaced_name -%>/engine', __dir__)
+<% if with_dummy_app? -%>
+APP_PATH = File.expand_path('../<%= dummy_path -%>/config/application', __dir__)
+<% end -%>
 
 # Set up gems listed in the Gemfile.
-ENV['BUNDLE_GEMFILE'] ||= File.expand_path('../../Gemfile', __FILE__)
+ENV['BUNDLE_GEMFILE'] ||= File.expand_path('../Gemfile', __dir__)
 require 'bundler/setup' if File.exist?(ENV['BUNDLE_GEMFILE'])
 
+<% if include_all_railties? -%>
 require 'rails/all'
+<% else -%>
+require "rails"
+# Pick the frameworks you want:
+require "active_model/railtie"
+require "active_job/railtie"
+<%= comment_if :skip_active_record %>require "active_record/railtie"
+require "action_controller/railtie"
+<%= comment_if :skip_action_mailer %>require "action_mailer/railtie"
+require "action_view/railtie"
+require "active_storage/engine"
+<%= comment_if :skip_action_cable %>require "action_cable/engine"
+<%= comment_if :skip_sprockets %>require "sprockets/railtie"
+<%= comment_if :skip_test %>require "rails/test_unit/railtie"
+<% end -%>
 require 'rails/engine/commands'
diff --git a/railties/lib/rails/generators/rails/plugin/templates/bin/test.tt b/railties/lib/rails/generators/rails/plugin/templates/bin/test.tt
index 62b94618fd..8e7d321626 100644
--- a/railties/lib/rails/generators/rails/plugin/templates/bin/test.tt
+++ b/railties/lib/rails/generators/rails/plugin/templates/bin/test.tt
@@ -1,8 +1,4 @@
-$: << File.expand_path(File.expand_path('../../test', __FILE__))
+$: << File.expand_path("../test", __dir__)
 
-require 'bundler/setup'
-require 'rails/test_unit/minitest_plugin'
-
-Rails::TestUnitReporter.executable = 'bin/test'
-
-exit Minitest.run(ARGV)
+require "bundler/setup"
+require "rails/plugin/test"
diff --git a/railties/lib/rails/generators/rails/plugin/templates/config/routes.rb b/railties/lib/rails/generators/rails/plugin/templates/config/routes.rb.tt
index 154452bfe5..154452bfe5 100644
--- a/railties/lib/rails/generators/rails/plugin/templates/config/routes.rb
+++ b/railties/lib/rails/generators/rails/plugin/templates/config/routes.rb.tt
diff --git a/railties/lib/rails/generators/rails/plugin/templates/gitignore b/railties/lib/rails/generators/rails/plugin/templates/gitignore
deleted file mode 100644
index 54c78d7927..0000000000
--- a/railties/lib/rails/generators/rails/plugin/templates/gitignore
+++ /dev/null
@@ -1,9 +0,0 @@
-.bundle/
-log/*.log
-pkg/
-<% unless options[:skip_test] && options[:dummy_path] == 'test/dummy' -%>
-<%= dummy_path %>/db/*.sqlite3
-<%= dummy_path %>/db/*.sqlite3-journal
-<%= dummy_path %>/log/*.log
-<%= dummy_path %>/tmp/
-<% end -%>
diff --git a/railties/lib/rails/generators/rails/plugin/templates/gitignore.tt b/railties/lib/rails/generators/rails/plugin/templates/gitignore.tt
new file mode 100644
index 0000000000..7a68da5c4b
--- /dev/null
+++ b/railties/lib/rails/generators/rails/plugin/templates/gitignore.tt
@@ -0,0 +1,18 @@
+.bundle/
+log/*.log
+pkg/
+<% if with_dummy_app? -%>
+<% if sqlite3? -%>
+<%= dummy_path %>/db/*.sqlite3
+<%= dummy_path %>/db/*.sqlite3-journal
+<% end -%>
+<%= dummy_path %>/log/*.log
+<% unless options[:skip_yarn] -%>
+<%= dummy_path %>/node_modules/
+<%= dummy_path %>/yarn-error.log
+<% end -%>
+<% unless skip_active_storage? -%>
+<%= dummy_path %>/storage/
+<% end -%>
+<%= dummy_path %>/tmp/
+<% end -%>
diff --git a/railties/lib/rails/generators/rails/plugin/templates/lib/%namespaced_name%.rb b/railties/lib/rails/generators/rails/plugin/templates/lib/%namespaced_name%.rb.tt
index 40b1c4cee7..3285055eb7 100644
--- a/railties/lib/rails/generators/rails/plugin/templates/lib/%namespaced_name%.rb
+++ b/railties/lib/rails/generators/rails/plugin/templates/lib/%namespaced_name%.rb.tt
@@ -1,5 +1,7 @@
 <% if engine? -%>
 require "<%= namespaced_name %>/engine"
-
+<% else -%>
+require "<%= namespaced_name %>/railtie"
 <% end -%>
+
 <%= wrap_in_modules "# Your code goes here..." %>
diff --git a/railties/lib/rails/generators/rails/plugin/templates/lib/%namespaced_name%/engine.rb b/railties/lib/rails/generators/rails/plugin/templates/lib/%namespaced_name%/engine.rb.tt
index 8938770fc4..8938770fc4 100644
--- a/railties/lib/rails/generators/rails/plugin/templates/lib/%namespaced_name%/engine.rb
+++ b/railties/lib/rails/generators/rails/plugin/templates/lib/%namespaced_name%/engine.rb.tt
diff --git a/railties/lib/rails/generators/rails/plugin/templates/lib/%namespaced_name%/railtie.rb.tt b/railties/lib/rails/generators/rails/plugin/templates/lib/%namespaced_name%/railtie.rb.tt
new file mode 100644
index 0000000000..7bdf4ee5fb
--- /dev/null
+++ b/railties/lib/rails/generators/rails/plugin/templates/lib/%namespaced_name%/railtie.rb.tt
@@ -0,0 +1,5 @@
+<%= wrap_in_modules <<-rb.strip_heredoc
+  class Railtie < ::Rails::Railtie
+  end
+rb
+%>
diff --git a/railties/lib/rails/generators/rails/plugin/templates/lib/%namespaced_name%/version.rb b/railties/lib/rails/generators/rails/plugin/templates/lib/%namespaced_name%/version.rb.tt
index b08f4ef9ae..b08f4ef9ae 100644
--- a/railties/lib/rails/generators/rails/plugin/templates/lib/%namespaced_name%/version.rb
+++ b/railties/lib/rails/generators/rails/plugin/templates/lib/%namespaced_name%/version.rb.tt
diff --git a/railties/lib/rails/generators/rails/plugin/templates/lib/tasks/%namespaced_name%_tasks.rake b/railties/lib/rails/generators/rails/plugin/templates/lib/tasks/%namespaced_name%_tasks.rake.tt
index 88a2c4120f..88a2c4120f 100644
--- a/railties/lib/rails/generators/rails/plugin/templates/lib/tasks/%namespaced_name%_tasks.rake
+++ b/railties/lib/rails/generators/rails/plugin/templates/lib/tasks/%namespaced_name%_tasks.rake.tt
diff --git a/railties/lib/rails/generators/rails/plugin/templates/rails/application.rb b/railties/lib/rails/generators/rails/plugin/templates/rails/application.rb.tt
index d03b1be878..06ffe2f1ed 100644
--- a/railties/lib/rails/generators/rails/plugin/templates/rails/application.rb
+++ b/railties/lib/rails/generators/rails/plugin/templates/rails/application.rb.tt
@@ -3,15 +3,18 @@ require_relative 'boot'
 <% if include_all_railties? -%>
 require 'rails/all'
 <% else -%>
+require "rails"
 # Pick the frameworks you want:
+require "active_model/railtie"
+require "active_job/railtie"
 <%= comment_if :skip_active_record %>require "active_record/railtie"
+<%= comment_if :skip_active_storage %>require "active_storage/engine"
 require "action_controller/railtie"
-require "action_view/railtie"
 <%= comment_if :skip_action_mailer %>require "action_mailer/railtie"
-require "active_job/railtie"
+require "action_view/railtie"
 <%= comment_if :skip_action_cable %>require "action_cable/engine"
-<%= comment_if :skip_test %>require "rails/test_unit/railtie"
 <%= comment_if :skip_sprockets %>require "sprockets/railtie"
+<%= comment_if :skip_test %>require "rails/test_unit/railtie"
 <% end -%>
 
 Bundler.require(*Rails.groups)
diff --git a/railties/lib/rails/generators/rails/plugin/templates/rails/boot.rb b/railties/lib/rails/generators/rails/plugin/templates/rails/boot.rb.tt
index c9aef85d40..c9aef85d40 100644
--- a/railties/lib/rails/generators/rails/plugin/templates/rails/boot.rb
+++ b/railties/lib/rails/generators/rails/plugin/templates/rails/boot.rb.tt
diff --git a/railties/lib/rails/generators/rails/plugin/templates/rails/dummy_manifest.js b/railties/lib/rails/generators/rails/plugin/templates/rails/dummy_manifest.js.tt
index 8d21b2b6fb..03937cf8ff 100644
--- a/railties/lib/rails/generators/rails/plugin/templates/rails/dummy_manifest.js
+++ b/railties/lib/rails/generators/rails/plugin/templates/rails/dummy_manifest.js.tt
@@ -1,4 +1,3 @@
-
 <% unless api? -%>
 //= link_tree ../images
 <% end -%>
diff --git a/railties/lib/rails/generators/rails/plugin/templates/rails/engine_manifest.js b/railties/lib/rails/generators/rails/plugin/templates/rails/engine_manifest.js.tt
index 2f23844f5e..2f23844f5e 100644
--- a/railties/lib/rails/generators/rails/plugin/templates/rails/engine_manifest.js
+++ b/railties/lib/rails/generators/rails/plugin/templates/rails/engine_manifest.js.tt
diff --git a/railties/lib/rails/generators/rails/plugin/templates/rails/javascripts.js.tt b/railties/lib/rails/generators/rails/plugin/templates/rails/javascripts.js.tt
new file mode 100644
index 0000000000..f3d80c87f5
--- /dev/null
+++ b/railties/lib/rails/generators/rails/plugin/templates/rails/javascripts.js.tt
@@ -0,0 +1,16 @@
+// This is a manifest file that'll be compiled into application.js, which will include all the files
+// listed below.
+//
+// Any JavaScript/Coffee file within this directory, lib/assets/javascripts, vendor/assets/javascripts,
+// or any plugin's vendor/assets/javascripts directory can be referenced here using a relative path.
+//
+// It's not advisable to add code directly here, but if you do, it'll appear at the bottom of the
+// compiled file. JavaScript code in this file should be added after the last require_* statement.
+//
+// Read Sprockets README (https://github.com/rails/sprockets#sprockets-directives) for details
+// about supported directives.
+//
+<% unless skip_active_storage? -%>
+//= require activestorage
+<% end -%>
+//= require_tree .
diff --git a/railties/lib/rails/generators/rails/plugin/templates/rails/routes.rb b/railties/lib/rails/generators/rails/plugin/templates/rails/routes.rb.tt
index 694510edc0..694510edc0 100644
--- a/railties/lib/rails/generators/rails/plugin/templates/rails/routes.rb
+++ b/railties/lib/rails/generators/rails/plugin/templates/rails/routes.rb.tt
diff --git a/railties/lib/rails/generators/rails/plugin/templates/test/%namespaced_name%_test.rb b/railties/lib/rails/generators/rails/plugin/templates/test/%namespaced_name%_test.rb.tt
index 1ee05d7871..1ee05d7871 100644
--- a/railties/lib/rails/generators/rails/plugin/templates/test/%namespaced_name%_test.rb
+++ b/railties/lib/rails/generators/rails/plugin/templates/test/%namespaced_name%_test.rb.tt
diff --git a/railties/lib/rails/generators/rails/plugin/templates/test/application_system_test_case.rb.tt b/railties/lib/rails/generators/rails/plugin/templates/test/application_system_test_case.rb.tt
new file mode 100644
index 0000000000..d19212abd5
--- /dev/null
+++ b/railties/lib/rails/generators/rails/plugin/templates/test/application_system_test_case.rb.tt
@@ -0,0 +1,5 @@
+require "test_helper"
+
+class ApplicationSystemTestCase < ActionDispatch::SystemTestCase
+  driven_by :selenium, using: :chrome, screen_size: [1400, 1400]
+end
diff --git a/railties/lib/rails/generators/rails/plugin/templates/test/integration/navigation_test.rb b/railties/lib/rails/generators/rails/plugin/templates/test/integration/navigation_test.rb.tt
index f5d1ec2046..29e59d8407 100644
--- a/railties/lib/rails/generators/rails/plugin/templates/test/integration/navigation_test.rb
+++ b/railties/lib/rails/generators/rails/plugin/templates/test/integration/navigation_test.rb.tt
@@ -5,4 +5,3 @@ class NavigationTest < ActionDispatch::IntegrationTest
   #   assert true
   # end
 end
-
diff --git a/railties/lib/rails/generators/rails/plugin/templates/test/test_helper.rb b/railties/lib/rails/generators/rails/plugin/templates/test/test_helper.rb.tt
index a5eebcb19f..755d19ef5d 100644
--- a/railties/lib/rails/generators/rails/plugin/templates/test/test_helper.rb
+++ b/railties/lib/rails/generators/rails/plugin/templates/test/test_helper.rb.tt
@@ -1,11 +1,11 @@
 # Configure Rails Environment
 ENV["RAILS_ENV"] = "test"
 
-require File.expand_path("../../<%= options[:dummy_path] -%>/config/environment.rb", __FILE__)
+require_relative "<%= File.join('..', options[:dummy_path], 'config/environment') -%>"
 <% unless options[:skip_active_record] -%>
-ActiveRecord::Migrator.migrations_paths = [File.expand_path("../../<%= options[:dummy_path] -%>/db/migrate", __FILE__)]
+ActiveRecord::Migrator.migrations_paths = [File.expand_path("../<%= options[:dummy_path] -%>/db/migrate", __dir__)]
 <% if options[:mountable] -%>
-ActiveRecord::Migrator.migrations_paths << File.expand_path('../../db/migrate', __FILE__)
+ActiveRecord::Migrator.migrations_paths << File.expand_path('../db/migrate', __dir__)
 <% end -%>
 <% end -%>
 require "rails/test_help"
@@ -15,13 +15,16 @@ require "rails/test_help"
 Minitest.backtrace_filter = Minitest::BacktraceFilter.new
 
 <% unless engine? -%>
+require "rails/test_unit/reporter"
 Rails::TestUnitReporter.executable = 'bin/test'
 <% end -%>
 
+<% unless options[:skip_active_record] -%>
 # Load fixtures from the engine
 if ActiveSupport::TestCase.respond_to?(:fixture_path=)
-  ActiveSupport::TestCase.fixture_path = File.expand_path("../fixtures", __FILE__)
+  ActiveSupport::TestCase.fixture_path = File.expand_path("fixtures", __dir__)
   ActionDispatch::IntegrationTest.fixture_path = ActiveSupport::TestCase.fixture_path
   ActiveSupport::TestCase.file_fixture_path = ActiveSupport::TestCase.fixture_path + "/files"
   ActiveSupport::TestCase.fixtures :all
 end
+<% end -%>
diff --git a/railties/lib/rails/generators/rails/resource/USAGE b/railties/lib/rails/generators/rails/resource/USAGE
index e359cd574f..66d0ee546a 100644
--- a/railties/lib/rails/generators/rails/resource/USAGE
+++ b/railties/lib/rails/generators/rails/resource/USAGE
@@ -1,6 +1,6 @@
 Description:
     Stubs out a new resource including an empty model and controller suitable
-    for a restful, resource-oriented application. Pass the singular model name,
+    for a RESTful, resource-oriented application. Pass the singular model name,
     either CamelCased or under_scored, as the first argument, and an optional
     list of attribute pairs.
 
diff --git a/railties/lib/rails/generators/rails/resource/resource_generator.rb b/railties/lib/rails/generators/rails/resource/resource_generator.rb
index 3acf21df13..3ba25ef0fe 100644
--- a/railties/lib/rails/generators/rails/resource/resource_generator.rb
+++ b/railties/lib/rails/generators/rails/resource/resource_generator.rb
@@ -1,5 +1,7 @@
-require 'rails/generators/resource_helpers'
-require 'rails/generators/rails/model/model_generator'
+# frozen_string_literal: true
+
+require "rails/generators/resource_helpers"
+require "rails/generators/rails/model/model_generator"
 
 module Rails
   module Generators
diff --git a/railties/lib/rails/generators/rails/resource_route/resource_route_generator.rb b/railties/lib/rails/generators/rails/resource_route/resource_route_generator.rb
index 42705107ae..9a92991efe 100644
--- a/railties/lib/rails/generators/rails/resource_route/resource_route_generator.rb
+++ b/railties/lib/rails/generators/rails/resource_route/resource_route_generator.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module Rails
   module Generators
     class ResourceRouteGenerator < NamedBase # :nodoc:
@@ -15,37 +17,32 @@ module Rails
       def add_resource_route
         return if options[:actions].present?
 
-        # iterates over all namespaces and opens up blocks
-        regular_class_path.each_with_index do |namespace, index|
-          write("namespace :#{namespace} do", index + 1)
+        depth = 0
+        lines = []
+
+        # Create 'namespace' ladder
+        # namespace :foo do
+        #   namespace :bar do
+        regular_class_path.each do |ns|
+          lines << indent("namespace :#{ns} do\n", depth * 2)
+          depth += 1
         end
 
         # inserts the primary resource
-        write("resources :#{file_name.pluralize}", route_length + 1)
+        # Create route
+        #     resources 'products'
+        lines << indent(%{resources :#{file_name.pluralize}\n}, depth * 2)
 
-        # ends blocks
-        regular_class_path.each_index do |index|
-          write("end", route_length - index)
+        # Create `end` ladder
+        #   end
+        # end
+        until depth.zero?
+          depth -= 1
+          lines << indent("end\n", depth * 2)
         end
 
-        # route prepends two spaces onto the front of the string that is passed, this corrects that.
-        # Also it adds a \n to the end of each line, as route already adds that
-        # we need to correct that too.
-        route route_string[2..-2]
+        route lines.join
       end
-
-      private
-        def route_string
-          @route_string ||= ""
-        end
-
-        def write(str, indent)
-          route_string << "#{"  " * indent}#{str}\n"
-        end
-
-        def route_length
-          regular_class_path.length
-        end
     end
   end
 end
diff --git a/railties/lib/rails/generators/rails/scaffold/scaffold_generator.rb b/railties/lib/rails/generators/rails/scaffold/scaffold_generator.rb
index 17c32bfdb3..8beb7416c0 100644
--- a/railties/lib/rails/generators/rails/scaffold/scaffold_generator.rb
+++ b/railties/lib/rails/generators/rails/scaffold/scaffold_generator.rb
@@ -1,4 +1,6 @@
-require 'rails/generators/rails/resource/resource_generator'
+# frozen_string_literal: true
+
+require "rails/generators/rails/resource/resource_generator"
 
 module Rails
   module Generators
@@ -6,6 +8,7 @@ module Rails
       remove_hook_for :resource_controller
       remove_class_option :actions
 
+      class_option :api, type: :boolean
       class_option :stylesheets, type: :boolean, desc: "Generate Stylesheets"
       class_option :stylesheet_engine, desc: "Engine for Stylesheets"
       class_option :assets, type: :boolean
diff --git a/railties/lib/rails/generators/rails/scaffold_controller/USAGE b/railties/lib/rails/generators/rails/scaffold_controller/USAGE
index 8ba4c5ccbc..28f229510b 100644
--- a/railties/lib/rails/generators/rails/scaffold_controller/USAGE
+++ b/railties/lib/rails/generators/rails/scaffold_controller/USAGE
@@ -12,7 +12,7 @@ Description:
 Example:
     `rails generate scaffold_controller CreditCard`
 
-    Credit card controller with URLs like /credit_card/debit.
+    Credit card controller with URLs like /credit_cards.
         Controller: app/controllers/credit_cards_controller.rb
         Test:       test/controllers/credit_cards_controller_test.rb
         Views:      app/views/credit_cards/index.html.erb [...]
diff --git a/railties/lib/rails/generators/rails/scaffold_controller/scaffold_controller_generator.rb b/railties/lib/rails/generators/rails/scaffold_controller/scaffold_controller_generator.rb
index d0b8cad896..7030561a33 100644
--- a/railties/lib/rails/generators/rails/scaffold_controller/scaffold_controller_generator.rb
+++ b/railties/lib/rails/generators/rails/scaffold_controller/scaffold_controller_generator.rb
@@ -1,4 +1,6 @@
-require 'rails/generators/resource_helpers'
+# frozen_string_literal: true
+
+require "rails/generators/resource_helpers"
 
 module Rails
   module Generators
@@ -17,10 +19,14 @@ module Rails
 
       def create_controller_files
         template_file = options.api? ? "api_controller.rb" : "controller.rb"
-        template template_file, File.join('app/controllers', controller_class_path, "#{controller_file_name}_controller.rb")
+        template template_file, File.join("app/controllers", controller_class_path, "#{controller_file_name}_controller.rb")
+      end
+
+      hook_for :template_engine, as: :scaffold do |template_engine|
+        invoke template_engine unless options.api?
       end
 
-      hook_for :template_engine, :test_framework, as: :scaffold
+      hook_for :test_framework, as: :scaffold
 
       # Invoke the helper using the controller name (pluralized)
       hook_for :helper, as: :scaffold do |invoked|
diff --git a/railties/lib/rails/generators/rails/scaffold_controller/templates/api_controller.rb b/railties/lib/rails/generators/rails/scaffold_controller/templates/api_controller.rb.tt
index 400afec6dc..400afec6dc 100644
--- a/railties/lib/rails/generators/rails/scaffold_controller/templates/api_controller.rb
+++ b/railties/lib/rails/generators/rails/scaffold_controller/templates/api_controller.rb.tt
diff --git a/railties/lib/rails/generators/rails/scaffold_controller/templates/controller.rb b/railties/lib/rails/generators/rails/scaffold_controller/templates/controller.rb.tt
index 42b9e34274..05f1c2b2d3 100644
--- a/railties/lib/rails/generators/rails/scaffold_controller/templates/controller.rb
+++ b/railties/lib/rails/generators/rails/scaffold_controller/templates/controller.rb.tt
@@ -29,7 +29,7 @@ class <%= controller_class_name %>Controller < ApplicationController
     @<%= singular_table_name %> = <%= orm_class.build(class_name, "#{singular_table_name}_params") %>
 
     if @<%= orm_instance.save %>
-      redirect_to @<%= singular_table_name %>, notice: <%= "'#{human_name} was successfully created.'" %>
+      redirect_to <%= redirect_resource_name %>, notice: <%= "'#{human_name} was successfully created.'" %>
     else
       render :new
     end
@@ -38,7 +38,7 @@ class <%= controller_class_name %>Controller < ApplicationController
   # PATCH/PUT <%= route_url %>/1
   def update
     if @<%= orm_instance.update("#{singular_table_name}_params") %>
-      redirect_to @<%= singular_table_name %>, notice: <%= "'#{human_name} was successfully updated.'" %>
+      redirect_to <%= redirect_resource_name %>, notice: <%= "'#{human_name} was successfully updated.'" %>
     else
       render :edit
     end
diff --git a/railties/lib/rails/generators/rails/system_test/USAGE b/railties/lib/rails/generators/rails/system_test/USAGE
new file mode 100644
index 0000000000..f11a99e008
--- /dev/null
+++ b/railties/lib/rails/generators/rails/system_test/USAGE
@@ -0,0 +1,10 @@
+Description:
+    Stubs out a new system test. Pass the name of the test, either
+    CamelCased or under_scored, as an argument.
+
+    This generator invokes the current system tool, which defaults to
+    TestUnit.
+
+Example:
+    `rails generate system_test GeneralStories` creates a GeneralStories
+    system test in test/system/general_stories_test.rb
diff --git a/railties/lib/rails/generators/rails/system_test/system_test_generator.rb b/railties/lib/rails/generators/rails/system_test/system_test_generator.rb
new file mode 100644
index 0000000000..7169e1bd3b
--- /dev/null
+++ b/railties/lib/rails/generators/rails/system_test/system_test_generator.rb
@@ -0,0 +1,9 @@
+# frozen_string_literal: true
+
+module Rails
+  module Generators
+    class SystemTestGenerator < NamedBase # :nodoc:
+      hook_for :system_tests, as: :system
+    end
+  end
+end
diff --git a/railties/lib/rails/generators/rails/task/task_generator.rb b/railties/lib/rails/generators/rails/task/task_generator.rb
index 754824ca0c..b7290a7447 100644
--- a/railties/lib/rails/generators/rails/task/task_generator.rb
+++ b/railties/lib/rails/generators/rails/task/task_generator.rb
@@ -1,12 +1,13 @@
+# frozen_string_literal: true
+
 module Rails
   module Generators
     class TaskGenerator < NamedBase # :nodoc:
       argument :actions, type: :array, default: [], banner: "action action"
 
       def create_task_files
-        template 'task.rb', File.join('lib/tasks', "#{file_name}.rake")
+        template "task.rb", File.join("lib/tasks", "#{file_name}.rake")
       end
-
     end
   end
 end
diff --git a/railties/lib/rails/generators/rails/task/templates/task.rb b/railties/lib/rails/generators/rails/task/templates/task.rb.tt
index 1e3ed5f158..1e3ed5f158 100644
--- a/railties/lib/rails/generators/rails/task/templates/task.rb
+++ b/railties/lib/rails/generators/rails/task/templates/task.rb.tt
diff --git a/railties/lib/rails/generators/resource_helpers.rb b/railties/lib/rails/generators/resource_helpers.rb
index 9c2037783e..a146a8fda6 100644
--- a/railties/lib/rails/generators/resource_helpers.rb
+++ b/railties/lib/rails/generators/resource_helpers.rb
@@ -1,12 +1,13 @@
-require 'rails/generators/active_model'
-require 'rails/generators/model_helpers'
+# frozen_string_literal: true
+
+require "rails/generators/active_model"
+require "rails/generators/model_helpers"
 
 module Rails
   module Generators
     # Deal with controller names on scaffold and add some helpers to deal with
     # ActiveModel.
     module ResourceHelpers # :nodoc:
-
       def self.included(base) #:nodoc:
         base.include(Rails::Generators::ModelHelpers)
         base.class_option :model_name, type: :string, desc: "ModelName to be used"
@@ -18,16 +19,20 @@ module Rails
         controller_name = name
         if options[:model_name]
           self.name = options[:model_name]
-          assign_names!(self.name)
+          assign_names!(name)
         end
 
         assign_controller_names!(controller_name.pluralize)
       end
 
+      # TODO Change this to private once we've dropped Ruby 2.2 support.
+      # Workaround for Ruby 2.2 "private attribute?" warning.
       protected
 
         attr_reader :controller_name, :controller_file_name
 
+      private
+
         def controller_class_path
           if options[:model_name]
             @controller_class_path
@@ -38,25 +43,25 @@ module Rails
 
         def assign_controller_names!(name)
           @controller_name = name
-          @controller_class_path = name.include?('/') ? name.split('/') : name.split('::')
+          @controller_class_path = name.include?("/") ? name.split("/") : name.split("::")
           @controller_class_path.map!(&:underscore)
           @controller_file_name = @controller_class_path.pop
         end
 
         def controller_file_path
-          @controller_file_path ||= (controller_class_path + [controller_file_name]).join('/')
+          @controller_file_path ||= (controller_class_path + [controller_file_name]).join("/")
         end
 
         def controller_class_name
-          (controller_class_path + [controller_file_name]).map!(&:camelize).join('::')
+          (controller_class_path + [controller_file_name]).map!(&:camelize).join("::")
         end
 
         def controller_i18n_scope
-          @controller_i18n_scope ||= controller_file_path.tr('/', '.')
+          @controller_i18n_scope ||= controller_file_path.tr("/", ".")
         end
 
         # Loads the ORM::Generators::ActiveModel class. This class is responsible
-        # to tell scaffold entities how to generate an specific method for the
+        # to tell scaffold entities how to generate a specific method for the
         # ORM. Check Rails::Generators::ActiveModel for more information.
         def orm_class
           @orm_class ||= begin
@@ -74,7 +79,7 @@ module Rails
         end
 
         # Initialize ORM::Generators::ActiveModel to access instance methods.
-        def orm_instance(name=singular_table_name)
+        def orm_instance(name = singular_table_name)
           @orm_instance ||= orm_class.new(name)
         end
     end
diff --git a/railties/lib/rails/generators/test_case.rb b/railties/lib/rails/generators/test_case.rb
index 58592b4f8e..5c71bf0be9 100644
--- a/railties/lib/rails/generators/test_case.rb
+++ b/railties/lib/rails/generators/test_case.rb
@@ -1,8 +1,10 @@
-require 'rails/generators'
-require 'rails/generators/testing/behaviour'
-require 'rails/generators/testing/setup_and_teardown'
-require 'rails/generators/testing/assertions'
-require 'fileutils'
+# frozen_string_literal: true
+
+require "rails/generators"
+require "rails/generators/testing/behaviour"
+require "rails/generators/testing/setup_and_teardown"
+require "rails/generators/testing/assertions"
+require "fileutils"
 
 module Rails
   module Generators
@@ -14,7 +16,7 @@ module Rails
     #
     #   class AppGeneratorTest < Rails::Generators::TestCase
     #     tests AppGenerator
-    #     destination File.expand_path("../tmp", File.dirname(__FILE__))
+    #     destination File.expand_path("../tmp", __dir__)
     #   end
     #
     # If you want to ensure your destination root is clean before running each test,
@@ -22,7 +24,7 @@ module Rails
     #
     #   class AppGeneratorTest < Rails::Generators::TestCase
     #     tests AppGenerator
-    #     destination File.expand_path("../tmp", File.dirname(__FILE__))
+    #     destination File.expand_path("../tmp", __dir__)
     #     setup :prepare_destination
     #   end
     class TestCase < ActiveSupport::TestCase
@@ -30,7 +32,6 @@ module Rails
       include Rails::Generators::Testing::SetupAndTeardown
       include Rails::Generators::Testing::Assertions
       include FileUtils
-
     end
   end
 end
diff --git a/railties/lib/rails/generators/test_unit.rb b/railties/lib/rails/generators/test_unit.rb
index fe45c9e15d..1005ac557c 100644
--- a/railties/lib/rails/generators/test_unit.rb
+++ b/railties/lib/rails/generators/test_unit.rb
@@ -1,4 +1,6 @@
-require 'rails/generators/named_base'
+# frozen_string_literal: true
+
+require "rails/generators/named_base"
 
 module TestUnit # :nodoc:
   module Generators # :nodoc:
diff --git a/railties/lib/rails/generators/test_unit/controller/controller_generator.rb b/railties/lib/rails/generators/test_unit/controller/controller_generator.rb
index b5aa581769..1a9ac6bf2a 100644
--- a/railties/lib/rails/generators/test_unit/controller/controller_generator.rb
+++ b/railties/lib/rails/generators/test_unit/controller/controller_generator.rb
@@ -1,4 +1,6 @@
-require 'rails/generators/test_unit'
+# frozen_string_literal: true
+
+require "rails/generators/test_unit"
 
 module TestUnit # :nodoc:
   module Generators # :nodoc:
@@ -7,8 +9,8 @@ module TestUnit # :nodoc:
       check_class_collision suffix: "ControllerTest"
 
       def create_test_files
-        template 'functional_test.rb',
-                 File.join('test/controllers', class_path, "#{file_name}_controller_test.rb")
+        template "functional_test.rb",
+                 File.join("test/controllers", class_path, "#{file_name}_controller_test.rb")
       end
     end
   end
diff --git a/railties/lib/rails/generators/test_unit/controller/templates/functional_test.rb b/railties/lib/rails/generators/test_unit/controller/templates/functional_test.rb.tt
index ff41fef9e9..ff41fef9e9 100644
--- a/railties/lib/rails/generators/test_unit/controller/templates/functional_test.rb
+++ b/railties/lib/rails/generators/test_unit/controller/templates/functional_test.rb.tt
diff --git a/railties/lib/rails/generators/test_unit/generator/generator_generator.rb b/railties/lib/rails/generators/test_unit/generator/generator_generator.rb
index d7307398ce..19be4f2f51 100644
--- a/railties/lib/rails/generators/test_unit/generator/generator_generator.rb
+++ b/railties/lib/rails/generators/test_unit/generator/generator_generator.rb
@@ -1,4 +1,6 @@
-require 'rails/generators/test_unit'
+# frozen_string_literal: true
+
+require "rails/generators/test_unit"
 
 module TestUnit # :nodoc:
   module Generators # :nodoc:
@@ -9,10 +11,10 @@ module TestUnit # :nodoc:
                                desc: "Namespace generator under lib/generators/name"
 
       def create_generator_files
-        template 'generator_test.rb', File.join('test/lib/generators', class_path, "#{file_name}_generator_test.rb")
+        template "generator_test.rb", File.join("test/lib/generators", class_path, "#{file_name}_generator_test.rb")
       end
 
-    protected
+    private
 
       def generator_path
         if options[:namespace]
diff --git a/railties/lib/rails/generators/test_unit/generator/templates/generator_test.rb b/railties/lib/rails/generators/test_unit/generator/templates/generator_test.rb.tt
index a7f1fc4fba..a7f1fc4fba 100644
--- a/railties/lib/rails/generators/test_unit/generator/templates/generator_test.rb
+++ b/railties/lib/rails/generators/test_unit/generator/templates/generator_test.rb.tt
diff --git a/railties/lib/rails/generators/test_unit/helper/helper_generator.rb b/railties/lib/rails/generators/test_unit/helper/helper_generator.rb
index bde4e88915..77308dcf7d 100644
--- a/railties/lib/rails/generators/test_unit/helper/helper_generator.rb
+++ b/railties/lib/rails/generators/test_unit/helper/helper_generator.rb
@@ -1,4 +1,6 @@
-require 'rails/generators/test_unit'
+# frozen_string_literal: true
+
+require "rails/generators/test_unit"
 
 module TestUnit # :nodoc:
   module Generators # :nodoc:
diff --git a/railties/lib/rails/generators/test_unit/integration/integration_generator.rb b/railties/lib/rails/generators/test_unit/integration/integration_generator.rb
index e004835bd5..ae307c5cd9 100644
--- a/railties/lib/rails/generators/test_unit/integration/integration_generator.rb
+++ b/railties/lib/rails/generators/test_unit/integration/integration_generator.rb
@@ -1,4 +1,6 @@
-require 'rails/generators/test_unit'
+# frozen_string_literal: true
+
+require "rails/generators/test_unit"
 
 module TestUnit # :nodoc:
   module Generators # :nodoc:
@@ -6,7 +8,7 @@ module TestUnit # :nodoc:
       check_class_collision suffix: "Test"
 
       def create_test_files
-        template 'integration_test.rb', File.join('test/integration', class_path, "#{file_name}_test.rb")
+        template "integration_test.rb", File.join("test/integration", class_path, "#{file_name}_test.rb")
       end
     end
   end
diff --git a/railties/lib/rails/generators/test_unit/integration/templates/integration_test.rb b/railties/lib/rails/generators/test_unit/integration/templates/integration_test.rb.tt
index dea7e22196..118e0f1271 100644
--- a/railties/lib/rails/generators/test_unit/integration/templates/integration_test.rb
+++ b/railties/lib/rails/generators/test_unit/integration/templates/integration_test.rb.tt
@@ -1,7 +1,9 @@
 require 'test_helper'
 
+<% module_namespacing do -%>
 class <%= class_name %>Test < ActionDispatch::IntegrationTest
   # test "the truth" do
   #   assert true
   # end
 end
+<% end -%>
diff --git a/railties/lib/rails/generators/test_unit/job/job_generator.rb b/railties/lib/rails/generators/test_unit/job/job_generator.rb
index 566b61ca66..a99ce914c0 100644
--- a/railties/lib/rails/generators/test_unit/job/job_generator.rb
+++ b/railties/lib/rails/generators/test_unit/job/job_generator.rb
@@ -1,12 +1,14 @@
-require 'rails/generators/test_unit'
+# frozen_string_literal: true
+
+require "rails/generators/test_unit"
 
 module TestUnit # :nodoc:
   module Generators # :nodoc:
     class JobGenerator < Base # :nodoc:
-      check_class_collision suffix: 'JobTest'
+      check_class_collision suffix: "JobTest"
 
       def create_test_file
-        template 'unit_test.rb.erb', File.join('test/jobs', class_path, "#{file_name}_job_test.rb")
+        template "unit_test.rb", File.join("test/jobs", class_path, "#{file_name}_job_test.rb")
       end
     end
   end
diff --git a/railties/lib/rails/generators/test_unit/job/templates/unit_test.rb.erb b/railties/lib/rails/generators/test_unit/job/templates/unit_test.rb.tt
index f5351d0ec6..f5351d0ec6 100644
--- a/railties/lib/rails/generators/test_unit/job/templates/unit_test.rb.erb
+++ b/railties/lib/rails/generators/test_unit/job/templates/unit_test.rb.tt
diff --git a/railties/lib/rails/generators/test_unit/mailer/mailer_generator.rb b/railties/lib/rails/generators/test_unit/mailer/mailer_generator.rb
index 76a0b79654..610d47a729 100644
--- a/railties/lib/rails/generators/test_unit/mailer/mailer_generator.rb
+++ b/railties/lib/rails/generators/test_unit/mailer/mailer_generator.rb
@@ -1,4 +1,6 @@
-require 'rails/generators/test_unit'
+# frozen_string_literal: true
+
+require "rails/generators/test_unit"
 
 module TestUnit # :nodoc:
   module Generators # :nodoc:
@@ -10,16 +12,16 @@ module TestUnit # :nodoc:
       end
 
       def create_test_files
-        template "functional_test.rb", File.join('test/mailers', class_path, "#{file_name}_mailer_test.rb")
+        template "functional_test.rb", File.join("test/mailers", class_path, "#{file_name}_mailer_test.rb")
       end
 
       def create_preview_files
-        template "preview.rb", File.join('test/mailers/previews', class_path, "#{file_name}_mailer_preview.rb")
+        template "preview.rb", File.join("test/mailers/previews", class_path, "#{file_name}_mailer_preview.rb")
       end
 
-      protected
+      private
         def file_name
-          @_file_name ||= super.gsub(/_mailer/i, '')
+          @_file_name ||= super.gsub(/_mailer/i, "")
         end
     end
   end
diff --git a/railties/lib/rails/generators/test_unit/mailer/templates/functional_test.rb b/railties/lib/rails/generators/test_unit/mailer/templates/functional_test.rb.tt
index a2f2d30de5..a2f2d30de5 100644
--- a/railties/lib/rails/generators/test_unit/mailer/templates/functional_test.rb
+++ b/railties/lib/rails/generators/test_unit/mailer/templates/functional_test.rb.tt
diff --git a/railties/lib/rails/generators/test_unit/mailer/templates/preview.rb b/railties/lib/rails/generators/test_unit/mailer/templates/preview.rb.tt
index b063cbc47b..b063cbc47b 100644
--- a/railties/lib/rails/generators/test_unit/mailer/templates/preview.rb
+++ b/railties/lib/rails/generators/test_unit/mailer/templates/preview.rb.tt
diff --git a/railties/lib/rails/generators/test_unit/model/model_generator.rb b/railties/lib/rails/generators/test_unit/model/model_generator.rb
index 086588750e..02d7502592 100644
--- a/railties/lib/rails/generators/test_unit/model/model_generator.rb
+++ b/railties/lib/rails/generators/test_unit/model/model_generator.rb
@@ -1,9 +1,10 @@
-require 'rails/generators/test_unit'
+# frozen_string_literal: true
+
+require "rails/generators/test_unit"
 
 module TestUnit # :nodoc:
   module Generators # :nodoc:
     class ModelGenerator < Base # :nodoc:
-
       RESERVED_YAML_KEYWORDS = %w(y yes n no true false on off null)
 
       argument :attributes, type: :array, default: [], banner: "field:type field:type"
@@ -12,14 +13,14 @@ module TestUnit # :nodoc:
       check_class_collision suffix: "Test"
 
       def create_test_file
-        template 'unit_test.rb', File.join('test/models', class_path, "#{file_name}_test.rb")
+        template "unit_test.rb", File.join("test/models", class_path, "#{file_name}_test.rb")
       end
 
       hook_for :fixture_replacement
 
       def create_fixture_file
         if options[:fixture] && options[:fixture_replacement].nil?
-          template 'fixtures.yml', File.join('test/fixtures', class_path, "#{fixture_file_name}.yml")
+          template "fixtures.yml", File.join("test/fixtures", class_path, "#{fixture_file_name}.yml")
         end
       end
 
diff --git a/railties/lib/rails/generators/test_unit/model/templates/fixtures.yml b/railties/lib/rails/generators/test_unit/model/templates/fixtures.yml.tt
index 0681780c97..0681780c97 100644
--- a/railties/lib/rails/generators/test_unit/model/templates/fixtures.yml
+++ b/railties/lib/rails/generators/test_unit/model/templates/fixtures.yml.tt
diff --git a/railties/lib/rails/generators/test_unit/model/templates/unit_test.rb b/railties/lib/rails/generators/test_unit/model/templates/unit_test.rb.tt
index c9bc7d5b90..c9bc7d5b90 100644
--- a/railties/lib/rails/generators/test_unit/model/templates/unit_test.rb
+++ b/railties/lib/rails/generators/test_unit/model/templates/unit_test.rb.tt
diff --git a/railties/lib/rails/generators/test_unit/plugin/plugin_generator.rb b/railties/lib/rails/generators/test_unit/plugin/plugin_generator.rb
index b5d4f38444..0657bc2389 100644
--- a/railties/lib/rails/generators/test_unit/plugin/plugin_generator.rb
+++ b/railties/lib/rails/generators/test_unit/plugin/plugin_generator.rb
@@ -1,4 +1,6 @@
-require 'rails/generators/test_unit'
+# frozen_string_literal: true
+
+require "rails/generators/test_unit"
 
 module TestUnit # :nodoc:
   module Generators # :nodoc:
@@ -6,7 +8,7 @@ module TestUnit # :nodoc:
       check_class_collision suffix: "Test"
 
       def create_test_files
-        directory '.', 'test'
+        directory ".", "test"
       end
     end
   end
diff --git a/railties/lib/rails/generators/test_unit/scaffold/scaffold_generator.rb b/railties/lib/rails/generators/test_unit/scaffold/scaffold_generator.rb
index 0171da7cc7..b6c13b41ae 100644
--- a/railties/lib/rails/generators/test_unit/scaffold/scaffold_generator.rb
+++ b/railties/lib/rails/generators/test_unit/scaffold/scaffold_generator.rb
@@ -1,5 +1,7 @@
-require 'rails/generators/test_unit'
-require 'rails/generators/resource_helpers'
+# frozen_string_literal: true
+
+require "rails/generators/test_unit"
+require "rails/generators/resource_helpers"
 
 module TestUnit # :nodoc:
   module Generators # :nodoc:
@@ -11,18 +13,25 @@ module TestUnit # :nodoc:
       class_option :api, type: :boolean,
                          desc: "Generates API functional tests"
 
+      class_option :system_tests, type: :string,
+                         desc: "Skip system test files"
+
       argument :attributes, type: :array, default: [], banner: "field:type field:type"
 
       def create_test_files
         template_file = options.api? ? "api_functional_test.rb" : "functional_test.rb"
         template template_file,
                  File.join("test/controllers", controller_class_path, "#{controller_file_name}_controller_test.rb")
+
+        unless options.api? || options[:system_tests].nil?
+          template "system_test.rb", File.join("test/system", class_path, "#{file_name.pluralize}_test.rb")
+        end
       end
 
       def fixture_name
         @fixture_name ||=
           if mountable_engine?
-            "%s_%s" % [namespaced_path, table_name]
+            (namespace_dirs + [table_name]).join("_")
           else
             table_name
           end
@@ -30,16 +39,20 @@ module TestUnit # :nodoc:
 
       private
 
+        def attributes_string
+          attributes_hash.map { |k, v| "#{k}: #{v}" }.join(", ")
+        end
+
         def attributes_hash
-          return if attributes_names.empty?
+          return {} if attributes_names.empty?
 
           attributes_names.map do |name|
             if %w(password password_confirmation).include?(name) && attributes.any?(&:password_digest?)
-              "#{name}: 'secret'"
+              ["#{name}", "'secret'"]
             else
-              "#{name}: @#{singular_table_name}.#{name}"
+              ["#{name}", "@#{singular_table_name}.#{name}"]
             end
-          end.sort.join(', ')
+          end.sort.to_h
         end
     end
   end
diff --git a/railties/lib/rails/generators/test_unit/scaffold/templates/api_functional_test.rb b/railties/lib/rails/generators/test_unit/scaffold/templates/api_functional_test.rb.tt
index c469c188e6..f21861d8e6 100644
--- a/railties/lib/rails/generators/test_unit/scaffold/templates/api_functional_test.rb
+++ b/railties/lib/rails/generators/test_unit/scaffold/templates/api_functional_test.rb.tt
@@ -17,7 +17,7 @@ class <%= controller_class_name %>ControllerTest < ActionDispatch::IntegrationTe
 
   test "should create <%= singular_table_name %>" do
     assert_difference('<%= class_name %>.count') do
-      post <%= index_helper %>_url, params: { <%= "#{singular_table_name}: { #{attributes_hash} }" %> }, as: :json
+      post <%= index_helper %>_url, params: { <%= "#{singular_table_name}: { #{attributes_string} }" %> }, as: :json
     end
 
     assert_response 201
@@ -29,7 +29,7 @@ class <%= controller_class_name %>ControllerTest < ActionDispatch::IntegrationTe
   end
 
   test "should update <%= singular_table_name %>" do
-    patch <%= show_helper %>, params: { <%= "#{singular_table_name}: { #{attributes_hash} }" %> }, as: :json
+    patch <%= show_helper %>, params: { <%= "#{singular_table_name}: { #{attributes_string} }" %> }, as: :json
     assert_response 200
   end
 
diff --git a/railties/lib/rails/generators/test_unit/scaffold/templates/functional_test.rb b/railties/lib/rails/generators/test_unit/scaffold/templates/functional_test.rb.tt
index c33375b7b4..195d60be20 100644
--- a/railties/lib/rails/generators/test_unit/scaffold/templates/functional_test.rb
+++ b/railties/lib/rails/generators/test_unit/scaffold/templates/functional_test.rb.tt
@@ -22,7 +22,7 @@ class <%= controller_class_name %>ControllerTest < ActionDispatch::IntegrationTe
 
   test "should create <%= singular_table_name %>" do
     assert_difference('<%= class_name %>.count') do
-      post <%= index_helper %>_url, params: { <%= "#{singular_table_name}: { #{attributes_hash} }" %> }
+      post <%= index_helper %>_url, params: { <%= "#{singular_table_name}: { #{attributes_string} }" %> }
     end
 
     assert_redirected_to <%= singular_table_name %>_url(<%= class_name %>.last)
@@ -39,7 +39,7 @@ class <%= controller_class_name %>ControllerTest < ActionDispatch::IntegrationTe
   end
 
   test "should update <%= singular_table_name %>" do
-    patch <%= show_helper %>, params: { <%= "#{singular_table_name}: { #{attributes_hash} }" %> }
+    patch <%= show_helper %>, params: { <%= "#{singular_table_name}: { #{attributes_string} }" %> }
     assert_redirected_to <%= singular_table_name %>_url(<%= "@#{singular_table_name}" %>)
   end
 
diff --git a/railties/lib/rails/generators/test_unit/scaffold/templates/system_test.rb.tt b/railties/lib/rails/generators/test_unit/scaffold/templates/system_test.rb.tt
new file mode 100644
index 0000000000..f83f5a5c62
--- /dev/null
+++ b/railties/lib/rails/generators/test_unit/scaffold/templates/system_test.rb.tt
@@ -0,0 +1,49 @@
+require "application_system_test_case"
+
+<% module_namespacing do -%>
+class <%= class_name.pluralize %>Test < ApplicationSystemTestCase
+  setup do
+    @<%= singular_table_name %> = <%= fixture_name %>(:one)
+  end
+
+  test "visiting the index" do
+    visit <%= plural_table_name %>_url
+    assert_selector "h1", text: "<%= class_name.pluralize.titleize %>"
+  end
+
+  test "creating a <%= human_name %>" do
+    visit <%= plural_table_name %>_url
+    click_on "New <%= class_name.titleize %>"
+
+    <%- attributes_hash.each do |attr, value| -%>
+    fill_in "<%= attr.humanize.titleize %>", with: <%= value %>
+    <%- end -%>
+    click_on "Create <%= human_name %>"
+
+    assert_text "<%= human_name %> was successfully created"
+    click_on "Back"
+  end
+
+  test "updating a <%= human_name %>" do
+    visit <%= plural_table_name %>_url
+    click_on "Edit", match: :first
+
+    <%- attributes_hash.each do |attr, value| -%>
+    fill_in "<%= attr.humanize.titleize %>", with: <%= value %>
+    <%- end -%>
+    click_on "Update <%= human_name %>"
+
+    assert_text "<%= human_name %> was successfully updated"
+    click_on "Back"
+  end
+
+  test "destroying a <%= human_name %>" do
+    visit <%= plural_table_name %>_url
+    page.accept_confirm do
+      click_on "Destroy", match: :first
+    end
+
+    assert_text "<%= human_name %> was successfully destroyed"
+  end
+end
+<% end -%>
diff --git a/railties/lib/rails/generators/test_unit/system/system_generator.rb b/railties/lib/rails/generators/test_unit/system/system_generator.rb
new file mode 100644
index 0000000000..08504d4124
--- /dev/null
+++ b/railties/lib/rails/generators/test_unit/system/system_generator.rb
@@ -0,0 +1,19 @@
+# frozen_string_literal: true
+
+require "rails/generators/test_unit"
+
+module TestUnit # :nodoc:
+  module Generators # :nodoc:
+    class SystemGenerator < Base # :nodoc:
+      check_class_collision suffix: "Test"
+
+      def create_test_files
+        if !File.exist?(File.join("test/application_system_test_case.rb"))
+          template "application_system_test_case.rb", File.join("test", "application_system_test_case.rb")
+        end
+
+        template "system_test.rb", File.join("test/system", class_path, "#{file_name.pluralize}_test.rb")
+      end
+    end
+  end
+end
diff --git a/railties/lib/rails/generators/test_unit/system/templates/application_system_test_case.rb.tt b/railties/lib/rails/generators/test_unit/system/templates/application_system_test_case.rb.tt
new file mode 100644
index 0000000000..d19212abd5
--- /dev/null
+++ b/railties/lib/rails/generators/test_unit/system/templates/application_system_test_case.rb.tt
@@ -0,0 +1,5 @@
+require "test_helper"
+
+class ApplicationSystemTestCase < ActionDispatch::SystemTestCase
+  driven_by :selenium, using: :chrome, screen_size: [1400, 1400]
+end
diff --git a/railties/lib/rails/generators/test_unit/system/templates/system_test.rb.tt b/railties/lib/rails/generators/test_unit/system/templates/system_test.rb.tt
new file mode 100644
index 0000000000..b5ce2ba5c8
--- /dev/null
+++ b/railties/lib/rails/generators/test_unit/system/templates/system_test.rb.tt
@@ -0,0 +1,9 @@
+require "application_system_test_case"
+
+class <%= class_name.pluralize %>Test < ApplicationSystemTestCase
+  # test "visiting the index" do
+  #   visit <%= plural_table_name %>_url
+  #
+  #   assert_selector "h1", text: "<%= class_name %>"
+  # end
+end
diff --git a/railties/lib/rails/generators/testing/assertions.rb b/railties/lib/rails/generators/testing/assertions.rb
index 76758df86d..c4cff9090b 100644
--- a/railties/lib/rails/generators/testing/assertions.rb
+++ b/railties/lib/rails/generators/testing/assertions.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module Rails
   module Generators
     module Testing
@@ -29,10 +31,10 @@ module Rails
 
           contents.each do |content|
             case content
-              when String
-                assert_equal content, read
-              when Regexp
-                assert_match content, read
+            when String
+              assert_equal content, read
+            when Regexp
+              assert_match content, read
             end
           end
         end
@@ -113,7 +115,11 @@ module Rails
         #
         #   assert_field_default_value :string, "MyString"
         def assert_field_default_value(attribute_type, value)
-          assert_equal(value, create_generated_attribute(attribute_type).default)
+          if value.nil?
+            assert_nil(create_generated_attribute(attribute_type).default)
+          else
+            assert_equal(value, create_generated_attribute(attribute_type).default)
+          end
         end
       end
     end
diff --git a/railties/lib/rails/generators/testing/behaviour.rb b/railties/lib/rails/generators/testing/behaviour.rb
index 94b5e52224..6ab88bd59f 100644
--- a/railties/lib/rails/generators/testing/behaviour.rb
+++ b/railties/lib/rails/generators/testing/behaviour.rb
@@ -1,10 +1,12 @@
-require 'active_support/core_ext/class/attribute'
-require 'active_support/core_ext/module/delegation'
-require 'active_support/core_ext/hash/reverse_merge'
-require 'active_support/core_ext/kernel/reporting'
-require 'active_support/testing/stream'
-require 'active_support/concern'
-require 'rails/generators'
+# frozen_string_literal: true
+
+require "active_support/core_ext/class/attribute"
+require "active_support/core_ext/module/delegation"
+require "active_support/core_ext/hash/reverse_merge"
+require "active_support/core_ext/kernel/reporting"
+require "active_support/testing/stream"
+require "active_support/concern"
+require "rails/generators"
 
 module Rails
   module Generators
@@ -14,12 +16,12 @@ module Rails
         include ActiveSupport::Testing::Stream
 
         included do
-          class_attribute :destination_root, :current_path, :generator_class, :default_arguments
-
           # Generators frequently change the current path using +FileUtils.cd+.
           # So we need to store the path at file load and revert back to it after each test.
-          self.current_path = File.expand_path(Dir.pwd)
-          self.default_arguments = []
+          class_attribute :current_path, default: File.expand_path(Dir.pwd)
+          class_attribute :default_arguments, default: []
+          class_attribute :destination_root
+          class_attribute :generator_class
         end
 
         module ClassMethods
@@ -40,7 +42,7 @@ module Rails
 
           # Sets the destination of generator files:
           #
-          #   destination File.expand_path("../tmp", File.dirname(__FILE__))
+          #   destination File.expand_path("../tmp", __dir__)
           def destination(path)
             self.destination_root = path
           end
@@ -51,7 +53,7 @@ module Rails
         #
         #   class AppGeneratorTest < Rails::Generators::TestCase
         #     tests AppGenerator
-        #     destination File.expand_path("../tmp", File.dirname(__FILE__))
+        #     destination File.expand_path("../tmp", __dir__)
         #     setup :prepare_destination
         #
         #     test "database.yml is not created when skipping Active Record" do
@@ -62,48 +64,47 @@ module Rails
         #
         # You can provide a configuration hash as second argument. This method returns the output
         # printed by the generator.
-        def run_generator(args=self.default_arguments, config={})
+        def run_generator(args = default_arguments, config = {})
           capture(:stdout) do
-            args += ['--skip-bundle'] unless args.include? '--dev'
-            self.generator_class.start(args, config.reverse_merge(destination_root: destination_root))
+            args += ["--skip-bundle"] unless args.include? "--dev"
+            generator_class.start(args, config.reverse_merge(destination_root: destination_root))
           end
         end
 
         # Instantiate the generator.
-        def generator(args=self.default_arguments, options={}, config={})
-          @generator ||= self.generator_class.new(args, options, config.reverse_merge(destination_root: destination_root))
+        def generator(args = default_arguments, options = {}, config = {})
+          @generator ||= generator_class.new(args, options, config.reverse_merge(destination_root: destination_root))
         end
 
         # Create a Rails::Generators::GeneratedAttribute by supplying the
         # attribute type and, optionally, the attribute name:
         #
         #   create_generated_attribute(:string, 'name')
-        def create_generated_attribute(attribute_type, name = 'test', index = nil)
-          Rails::Generators::GeneratedAttribute.parse([name, attribute_type, index].compact.join(':'))
+        def create_generated_attribute(attribute_type, name = "test", index = nil)
+          Rails::Generators::GeneratedAttribute.parse([name, attribute_type, index].compact.join(":"))
         end
 
-        protected
+        private
 
-          def destination_root_is_set? # :nodoc:
+          def destination_root_is_set?
             raise "You need to configure your Rails::Generators::TestCase destination root." unless destination_root
           end
 
-          def ensure_current_path # :nodoc:
+          def ensure_current_path
             cd current_path
           end
 
           # Clears all files and directories in destination.
-          def prepare_destination
+          def prepare_destination # :doc:
             rm_rf(destination_root)
             mkdir_p(destination_root)
           end
 
-          def migration_file_name(relative) # :nodoc:
+          def migration_file_name(relative)
             absolute = File.expand_path(relative, destination_root)
-            dirname, file_name = File.dirname(absolute), File.basename(absolute).sub(/\.rb$/, '')
+            dirname, file_name = File.dirname(absolute), File.basename(absolute).sub(/\.rb$/, "")
             Dir.glob("#{dirname}/[0-9]*_*.rb").grep(/\d+_#{file_name}.rb$/).first
           end
-
       end
     end
   end
diff --git a/railties/lib/rails/generators/testing/setup_and_teardown.rb b/railties/lib/rails/generators/testing/setup_and_teardown.rb
index 73102a283f..4374aa5b8c 100644
--- a/railties/lib/rails/generators/testing/setup_and_teardown.rb
+++ b/railties/lib/rails/generators/testing/setup_and_teardown.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module Rails
   module Generators
     module Testing
diff --git a/railties/lib/rails/info.rb b/railties/lib/rails/info.rb
index 5909446b66..d8f361f524 100644
--- a/railties/lib/rails/info.rb
+++ b/railties/lib/rails/info.rb
@@ -1,12 +1,15 @@
+# frozen_string_literal: true
+
 require "cgi"
 
 module Rails
-  # This module helps build the runtime properties used to display in the
-  # Rails::InfoController responses. Including the active Rails version, Ruby
-  # version, Rack version, and so on.
+  # This module helps build the runtime properties that are displayed in
+  # Rails::InfoController responses. These include the active Rails version,
+  # Ruby version, Rack version, and so on.
   module Info
-    mattr_accessor :properties
-    class << (@@properties = [])
+    mattr_accessor :properties, default: []
+
+    class << @@properties
       def names
         map(&:first)
       end
@@ -38,64 +41,64 @@ module Rails
       alias inspect to_s
 
       def to_html
-        '<table>'.tap do |table|
+        "<table>".dup.tap do |table|
           properties.each do |(name, value)|
             table << %(<tr><td class="name">#{CGI.escapeHTML(name.to_s)}</td>)
             formatted_value = if value.kind_of?(Array)
-                  "<ul>" + value.map { |v| "<li>#{CGI.escapeHTML(v.to_s)}</li>" }.join + "</ul>"
-                else
-                  CGI.escapeHTML(value.to_s)
-                end
+              "<ul>" + value.map { |v| "<li>#{CGI.escapeHTML(v.to_s)}</li>" }.join + "</ul>"
+            else
+              CGI.escapeHTML(value.to_s)
+            end
             table << %(<td class="value">#{formatted_value}</td></tr>)
           end
-          table << '</table>'
+          table << "</table>"
         end
       end
     end
 
     # The Rails version.
-    property 'Rails version' do
+    property "Rails version" do
       Rails.version.to_s
     end
 
     # The Ruby version and platform, e.g. "2.0.0-p247 (x86_64-darwin12.4.0)".
-    property 'Ruby version' do
+    property "Ruby version" do
       "#{RUBY_VERSION}-p#{RUBY_PATCHLEVEL} (#{RUBY_PLATFORM})"
     end
 
     # The RubyGems version, if it's installed.
-    property 'RubyGems version' do
+    property "RubyGems version" do
       Gem::RubyGemsVersion
     end
 
-    property 'Rack version' do
+    property "Rack version" do
       ::Rack.release
     end
 
-    property 'JavaScript Runtime' do
+    property "JavaScript Runtime" do
       ExecJS.runtime.name
     end
 
-    property 'Middleware' do
+    property "Middleware" do
       Rails.configuration.middleware.map(&:inspect)
     end
 
     # The application's location on the filesystem.
-    property 'Application root' do
+    property "Application root" do
       File.expand_path(Rails.root)
     end
 
     # The current Rails environment (development, test, or production).
-    property 'Environment' do
+    property "Environment" do
       Rails.env
     end
 
     # The name of the database adapter for the current environment.
-    property 'Database adapter' do
-      ActiveRecord::Base.configurations[Rails.env]['adapter']
+    property "Database adapter" do
+      ActiveRecord::Base.configurations[Rails.env]["adapter"]
     end
 
-    property 'Database schema version' do
+    property "Database schema version" do
       ActiveRecord::Migrator.current_version rescue nil
     end
   end
diff --git a/railties/lib/rails/info_controller.rb b/railties/lib/rails/info_controller.rb
index 778105c5f7..b4f4a5922a 100644
--- a/railties/lib/rails/info_controller.rb
+++ b/railties/lib/rails/info_controller.rb
@@ -1,9 +1,11 @@
-require 'rails/application_controller'
-require 'action_dispatch/routing/inspector'
+# frozen_string_literal: true
+
+require "rails/application_controller"
+require "action_dispatch/routing/inspector"
 
 class Rails::InfoController < Rails::ApplicationController # :nodoc:
   prepend_view_path ActionDispatch::DebugExceptions::RESCUES_TEMPLATE_PATH
-  layout -> { request.xhr? ? false : 'application' }
+  layout -> { request.xhr? ? false : "application" }
 
   before_action :require_local!
 
@@ -13,7 +15,7 @@ class Rails::InfoController < Rails::ApplicationController # :nodoc:
 
   def properties
     @info = Rails::Info.to_html
-    @page_title = 'Properties'
+    @page_title = "Properties"
   end
 
   def routes
@@ -21,24 +23,24 @@ class Rails::InfoController < Rails::ApplicationController # :nodoc:
       path = URI.parser.escape path
       normalized_path = with_leading_slash path
       render json: {
-        exact: match_route {|it| it.match normalized_path },
-        fuzzy: match_route {|it| it.spec.to_s.match path }
+        exact: match_route { |it| it.match normalized_path },
+        fuzzy: match_route { |it| it.spec.to_s.match path }
       }
     else
       @routes_inspector = ActionDispatch::Routing::RoutesInspector.new(_routes.routes)
-      @page_title = 'Routes'
+      @page_title = "Routes"
     end
   end
 
   private
 
-  def match_route
-    _routes.routes.select {|route|
-      yield route.path
-    }.map {|route| route.path.spec.to_s }
-  end
+    def match_route
+      _routes.routes.select { |route|
+        yield route.path
+      }.map { |route| route.path.spec.to_s }
+    end
 
-  def with_leading_slash(path)
-    ('/' + path).squeeze('/')
-  end
+    def with_leading_slash(path)
+      ("/" + path).squeeze("/")
+    end
 end
diff --git a/railties/lib/rails/initializable.rb b/railties/lib/rails/initializable.rb
index 1a0b6d1e1a..5410e17153 100644
--- a/railties/lib/rails/initializable.rb
+++ b/railties/lib/rails/initializable.rb
@@ -1,4 +1,6 @@
-require 'tsort'
+# frozen_string_literal: true
+
+require "tsort"
 
 module Rails
   module Initializable
@@ -34,6 +36,10 @@ module Rails
         return self if @context
         Initializer.new(@name, context, @options, &block)
       end
+
+      def context_class
+        @context.class
+      end
     end
 
     class Collection < Array
@@ -49,7 +55,7 @@ module Rails
       end
     end
 
-    def run_initializers(group=:default, *args)
+    def run_initializers(group = :default, *args)
       return if instance_variable_defined?(:@ran)
       initializers.tsort_each do |initializer|
         initializer.run(*args) if initializer.belongs_to?(group)
diff --git a/railties/lib/rails/mailers_controller.rb b/railties/lib/rails/mailers_controller.rb
index 6143cf2dd9..66636e5d6b 100644
--- a/railties/lib/rails/mailers_controller.rb
+++ b/railties/lib/rails/mailers_controller.rb
@@ -1,4 +1,6 @@
-require 'rails/application_controller'
+# frozen_string_literal: true
+
+require "rails/application_controller"
 
 class Rails::MailersController < Rails::ApplicationController # :nodoc:
   prepend_view_path ActionDispatch::DebugExceptions::RESCUES_TEMPLATE_PATH
@@ -6,6 +8,8 @@ class Rails::MailersController < Rails::ApplicationController # :nodoc:
   before_action :require_local!, unless: :show_previews?
   before_action :find_preview, only: :preview
 
+  helper_method :part_query
+
   def index
     @previews = ActionMailer::Preview.all
     @page_title = "Mailer Previews"
@@ -14,12 +18,12 @@ class Rails::MailersController < Rails::ApplicationController # :nodoc:
   def preview
     if params[:path] == @preview.preview_name
       @page_title = "Mailer Previews for #{@preview.preview_name}"
-      render action: 'mailer'
+      render action: "mailer"
     else
       @email_action = File.basename(params[:path])
 
       if @preview.email_exists?(@email_action)
-        @email = @preview.call(@email_action)
+        @email = @preview.call(@email_action, params)
 
         if params[:part]
           part_type = Mime::Type.lookup(params[:part])
@@ -32,7 +36,7 @@ class Rails::MailersController < Rails::ApplicationController # :nodoc:
           end
         else
           @part = find_preferred_part(request.format, Mime[:html], Mime[:text])
-          render action: 'email', layout: false, formats: %w[html]
+          render action: "email", layout: false, formats: %w[html]
         end
       else
         raise AbstractController::ActionNotFound, "Email '#{@email_action}' not found in #{@preview.name}"
@@ -40,15 +44,15 @@ class Rails::MailersController < Rails::ApplicationController # :nodoc:
     end
   end
 
-  protected
-    def show_previews?
+  private
+    def show_previews? # :doc:
       ActionMailer::Base.show_previews
     end
 
-    def find_preview
+    def find_preview # :doc:
       candidates = []
-      params[:path].to_s.scan(%r{/|$}){ candidates << $` }
-      preview = candidates.detect{ |candidate| ActionMailer::Preview.exists?(candidate) }
+      params[:path].to_s.scan(%r{/|$}) { candidates << $` }
+      preview = candidates.detect { |candidate| ActionMailer::Preview.exists?(candidate) }
 
       if preview
         @preview = ActionMailer::Preview.find(preview)
@@ -57,23 +61,27 @@ class Rails::MailersController < Rails::ApplicationController # :nodoc:
       end
     end
 
-    def find_preferred_part(*formats)
+    def find_preferred_part(*formats) # :doc:
       formats.each do |format|
         if part = @email.find_first_mime_type(format)
           return part
         end
       end
 
-      if formats.any?{ |f| @email.mime_type == f }
+      if formats.any? { |f| @email.mime_type == f }
         @email
       end
     end
 
-    def find_part(format)
+    def find_part(format) # :doc:
       if part = @email.find_first_mime_type(format)
         part
       elsif @email.mime_type == format
         @email
       end
     end
+
+    def part_query(mime_type)
+      request.query_parameters.merge(part: mime_type).to_query
+    end
 end
diff --git a/railties/lib/rails/paths.rb b/railties/lib/rails/paths.rb
index e47616a87f..87222563fd 100644
--- a/railties/lib/rails/paths.rb
+++ b/railties/lib/rails/paths.rb
@@ -1,13 +1,15 @@
+# frozen_string_literal: true
+
 module Rails
   module Paths
     # This object is an extended hash that behaves as root of the <tt>Rails::Paths</tt> system.
     # It allows you to collect information about how you want to structure your application
-    # paths by a Hash like API. It requires you to give a physical path on initialization.
+    # paths through a Hash-like API. It requires you to give a physical path on initialization.
     #
     #   root = Root.new "/rails"
     #   root.add "app/controllers", eager_load: true
     #
-    # The command above creates a new root object and adds "app/controllers" as a path.
+    # The above command creates a new root object and adds "app/controllers" as a path.
     # This means we can get a <tt>Rails::Paths::Path</tt> object back like below:
     #
     #   path = root["app/controllers"]
@@ -30,7 +32,7 @@ module Rails
     #   root["config/routes"].inspect # => ["config/routes.rb"]
     #
     # The +add+ method accepts the following options as arguments:
-    # eager_load, autoload, autoload_once and glob.
+    # eager_load, autoload, autoload_once, and glob.
     #
     # Finally, the +Path+ object also provides a few helpers:
     #
@@ -45,7 +47,6 @@ module Rails
       attr_accessor :path
 
       def initialize(path)
-        @current = nil
         @path = path
         @root = {}
       end
@@ -180,7 +181,7 @@ module Rails
       end
 
       def extensions # :nodoc:
-        $1.split(',') if @glob =~ /\{([\S]+)\}/
+        $1.split(",") if @glob =~ /\{([\S]+)\}/
       end
 
       # Expands all paths against the root and return all unique values.
@@ -206,7 +207,14 @@ module Rails
 
       # Returns all expanded paths but only if they exist in the filesystem.
       def existent
-        expanded.select { |f| File.exist?(f) }
+        expanded.select do |f|
+          does_exist = File.exist?(f)
+
+          if !does_exist && File.symlink?(f)
+            raise "File #{f.inspect} is a symlink that does not point to a valid file"
+          end
+          does_exist
+        end
       end
 
       def existent_directories
diff --git a/railties/lib/rails/plugin/test.rb b/railties/lib/rails/plugin/test.rb
new file mode 100644
index 0000000000..18b6fd1757
--- /dev/null
+++ b/railties/lib/rails/plugin/test.rb
@@ -0,0 +1,9 @@
+# frozen_string_literal: true
+
+require "rails/test_unit/runner"
+require "rails/test_unit/reporter"
+
+Rails::TestUnitReporter.executable = "bin/test"
+
+Rails::TestUnit::Runner.parse_options(ARGV)
+Rails::TestUnit::Runner.run(ARGV)
diff --git a/railties/lib/rails/rack.rb b/railties/lib/rails/rack.rb
index a4c4527a72..579fb25cc4 100644
--- a/railties/lib/rails/rack.rb
+++ b/railties/lib/rails/rack.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module Rails
   module Rack
     autoload :Logger, "rails/rack/logger"
diff --git a/railties/lib/rails/rack/debugger.rb b/railties/lib/rails/rack/debugger.rb
deleted file mode 100644
index 1fde3db070..0000000000
--- a/railties/lib/rails/rack/debugger.rb
+++ /dev/null
@@ -1,3 +0,0 @@
-require 'active_support/deprecation'
-
-ActiveSupport::Deprecation.warn("This file is deprecated and will be removed in Rails 5.1 with no replacement.")
diff --git a/railties/lib/rails/rack/logger.rb b/railties/lib/rails/rack/logger.rb
index b63d3a58d2..ec5212ee76 100644
--- a/railties/lib/rails/rack/logger.rb
+++ b/railties/lib/rails/rack/logger.rb
@@ -1,8 +1,10 @@
-require 'active_support/core_ext/time/conversions'
-require 'active_support/core_ext/object/blank'
-require 'active_support/log_subscriber'
-require 'action_dispatch/http/request'
-require 'rack/body_proxy'
+# frozen_string_literal: true
+
+require "active_support/core_ext/time/conversions"
+require "active_support/core_ext/object/blank"
+require "active_support/log_subscriber"
+require "action_dispatch/http/request"
+require "rack/body_proxy"
 
 module Rails
   module Rack
@@ -27,54 +29,52 @@ module Rails
         end
       end
 
-    protected
+      private
 
-      def call_app(request, env)
-        instrumenter = ActiveSupport::Notifications.instrumenter
-        instrumenter.start 'request.action_dispatch', request: request
-        logger.info { started_request_message(request) }
-        resp = @app.call(env)
-        resp[2] = ::Rack::BodyProxy.new(resp[2]) { finish(request) }
-        resp
-      rescue Exception
-        finish(request)
-        raise
-      ensure
-        ActiveSupport::LogSubscriber.flush_all!
-      end
+        def call_app(request, env) # :doc:
+          instrumenter = ActiveSupport::Notifications.instrumenter
+          instrumenter.start "request.action_dispatch", request: request
+          logger.info { started_request_message(request) }
+          resp = @app.call(env)
+          resp[2] = ::Rack::BodyProxy.new(resp[2]) { finish(request) }
+          resp
+        rescue Exception
+          finish(request)
+          raise
+        ensure
+          ActiveSupport::LogSubscriber.flush_all!
+        end
 
-      # Started GET "/session/new" for 127.0.0.1 at 2012-09-26 14:51:42 -0700
-      def started_request_message(request)
-        'Started %s "%s" for %s at %s' % [
-          request.request_method,
-          request.filtered_path,
-          request.ip,
-          Time.now.to_default_s ]
-      end
+        # Started GET "/session/new" for 127.0.0.1 at 2012-09-26 14:51:42 -0700
+        def started_request_message(request) # :doc:
+          'Started %s "%s" for %s at %s' % [
+            request.request_method,
+            request.filtered_path,
+            request.ip,
+            Time.now.to_default_s ]
+        end
 
-      def compute_tags(request)
-        @taggers.collect do |tag|
-          case tag
-          when Proc
-            tag.call(request)
-          when Symbol
-            request.send(tag)
-          else
-            tag
+        def compute_tags(request) # :doc:
+          @taggers.collect do |tag|
+            case tag
+            when Proc
+              tag.call(request)
+            when Symbol
+              request.send(tag)
+            else
+              tag
+            end
           end
         end
-      end
 
-      private
-
-      def finish(request)
-        instrumenter = ActiveSupport::Notifications.instrumenter
-        instrumenter.finish 'request.action_dispatch', request: request
-      end
+        def finish(request)
+          instrumenter = ActiveSupport::Notifications.instrumenter
+          instrumenter.finish "request.action_dispatch", request: request
+        end
 
-      def logger
-        Rails.logger
-      end
+        def logger
+          Rails.logger
+        end
     end
   end
 end
diff --git a/railties/lib/rails/railtie.rb b/railties/lib/rails/railtie.rb
index 492c519222..88dd932370 100644
--- a/railties/lib/rails/railtie.rb
+++ b/railties/lib/rails/railtie.rb
@@ -1,7 +1,9 @@
-require 'rails/initializable'
-require 'active_support/inflector'
-require 'active_support/core_ext/module/introspection'
-require 'active_support/core_ext/module/delegation'
+# frozen_string_literal: true
+
+require "rails/initializable"
+require "active_support/inflector"
+require "active_support/core_ext/module/introspection"
+require "active_support/core_ext/module/delegation"
 
 module Rails
   # <tt>Rails::Railtie</tt> is the core of the Rails framework and provides
@@ -103,6 +105,9 @@ module Rails
   #     end
   #   end
   #
+  # Since filenames on the load path are shared across gems, be sure that files you load
+  # through a railtie have unique names.
+  #
   # == Application and Engine
   #
   # An engine is nothing more than a railtie with some initializers already set. And since
@@ -111,7 +116,7 @@ module Rails
   #
   # Be sure to look at the documentation of those specific classes for more information.
   class Railtie
-    autoload :Configuration, 'rails/railtie/configuration'
+    autoload :Configuration, "rails/railtie/configuration"
 
     include Initializable
 
@@ -132,27 +137,19 @@ module Rails
       end
 
       def rake_tasks(&blk)
-        @rake_tasks ||= []
-        @rake_tasks << blk if blk
-        @rake_tasks
+        register_block_for(:rake_tasks, &blk)
       end
 
       def console(&blk)
-        @load_console ||= []
-        @load_console << blk if blk
-        @load_console
+        register_block_for(:load_console, &blk)
       end
 
       def runner(&blk)
-        @load_runner ||= []
-        @load_runner << blk if blk
-        @load_runner
+        register_block_for(:runner, &blk)
       end
 
       def generators(&blk)
-        @generators ||= []
-        @generators << blk if blk
-        @generators
+        register_block_for(:generators, &blk)
       end
 
       def abstract_railtie?
@@ -170,10 +167,6 @@ module Rails
         @instance ||= new
       end
 
-      def respond_to_missing?(*args)
-        instance.respond_to?(*args) || super
-      end
-
       # Allows you to configure the railtie. This is the same method seen in
       # Railtie::Configurable, but this module is no longer required for all
       # subclasses of Railtie so we provide the class method here.
@@ -181,11 +174,15 @@ module Rails
         instance.configure(&block)
       end
 
-      protected
-        def generate_railtie_name(string) #:nodoc:
+      private
+        def generate_railtie_name(string)
           ActiveSupport::Inflector.underscore(string).tr("/", "_")
         end
 
+        def respond_to_missing?(name, _)
+          instance.respond_to?(name) || super
+        end
+
         # If the class method does not have a method, then send the method call
         # to the Railtie instance.
         def method_missing(name, *args, &block)
@@ -195,6 +192,16 @@ module Rails
             super
           end
         end
+
+        # receives an instance variable identifier, set the variable value if is
+        # blank and append given block to value, which will be used later in
+        # `#each_registered_block(type, &block)`
+        def register_block_for(type, &blk)
+          var_name = "@#{type}"
+          blocks = instance_variable_defined?(var_name) ? instance_variable_get(var_name) : instance_variable_set(var_name, [])
+          blocks << blk if blk
+          blocks
+        end
     end
 
     delegate :railtie_name, to: :class
@@ -222,31 +229,32 @@ module Rails
 
     protected
 
-    def run_console_blocks(app) #:nodoc:
-      each_registered_block(:console) { |block| block.call(app) }
-    end
+      def run_console_blocks(app) #:nodoc:
+        each_registered_block(:console) { |block| block.call(app) }
+      end
 
-    def run_generators_blocks(app) #:nodoc:
-      each_registered_block(:generators) { |block| block.call(app) }
-    end
+      def run_generators_blocks(app) #:nodoc:
+        each_registered_block(:generators) { |block| block.call(app) }
+      end
 
-    def run_runner_blocks(app) #:nodoc:
-      each_registered_block(:runner) { |block| block.call(app) }
-    end
+      def run_runner_blocks(app) #:nodoc:
+        each_registered_block(:runner) { |block| block.call(app) }
+      end
 
-    def run_tasks_blocks(app) #:nodoc:
-      extend Rake::DSL
-      each_registered_block(:rake_tasks) { |block| instance_exec(app, &block) }
-    end
+      def run_tasks_blocks(app) #:nodoc:
+        extend Rake::DSL
+        each_registered_block(:rake_tasks) { |block| instance_exec(app, &block) }
+      end
 
     private
 
-    def each_registered_block(type, &block)
-      klass = self.class
-      while klass.respond_to?(type)
-        klass.public_send(type).each(&block)
-        klass = klass.superclass
+      # run `&block` in every registered block in `#register_block_for`
+      def each_registered_block(type, &block)
+        klass = self.class
+        while klass.respond_to?(type)
+          klass.public_send(type).each(&block)
+          klass = klass.superclass
+        end
       end
-    end
   end
 end
diff --git a/railties/lib/rails/railtie/configurable.rb b/railties/lib/rails/railtie/configurable.rb
index 1572af0b2a..7f42fae10a 100644
--- a/railties/lib/rails/railtie/configurable.rb
+++ b/railties/lib/rails/railtie/configurable.rb
@@ -1,4 +1,6 @@
-require 'active_support/concern'
+# frozen_string_literal: true
+
+require "active_support/concern"
 
 module Rails
   class Railtie
@@ -9,7 +11,7 @@ module Rails
         delegate :config, to: :instance
 
         def inherited(base)
-          raise "You cannot inherit from a #{self.superclass.name} child"
+          raise "You cannot inherit from a #{superclass.name} child"
         end
 
         def instance
@@ -24,11 +26,11 @@ module Rails
           class_eval(&block)
         end
 
-        protected
+        private
 
-        def method_missing(*args, &block)
-          instance.send(*args, &block)
-        end
+          def method_missing(*args, &block)
+            instance.send(*args, &block)
+          end
       end
     end
   end
diff --git a/railties/lib/rails/railtie/configuration.rb b/railties/lib/rails/railtie/configuration.rb
index eb3b2d8ef4..70274b948c 100644
--- a/railties/lib/rails/railtie/configuration.rb
+++ b/railties/lib/rails/railtie/configuration.rb
@@ -1,4 +1,6 @@
-require 'rails/configuration'
+# frozen_string_literal: true
+
+require "rails/configuration"
 
 module Rails
   class Railtie
@@ -53,7 +55,7 @@ module Rails
         ActiveSupport.on_load(:before_configuration, yield: true, &block)
       end
 
-      # Third configurable block to run. Does not run if +config.cache_classes+
+      # Third configurable block to run. Does not run if +config.eager_load+
       # set to false.
       def before_eager_load(&block)
         ActiveSupport.on_load(:before_eager_load, yield: true, &block)
diff --git a/railties/lib/rails/ruby_version_check.rb b/railties/lib/rails/ruby_version_check.rb
index 67a19d8a94..76b6b80d28 100644
--- a/railties/lib/rails/ruby_version_check.rb
+++ b/railties/lib/rails/ruby_version_check.rb
@@ -1,4 +1,6 @@
-if RUBY_VERSION < '2.2.2' && RUBY_ENGINE == 'ruby'
+# frozen_string_literal: true
+
+if RUBY_VERSION < "2.2.2" && RUBY_ENGINE == "ruby"
   desc = defined?(RUBY_DESCRIPTION) ? RUBY_DESCRIPTION : "ruby #{RUBY_VERSION} (#{RUBY_RELEASE_DATE})"
   abort <<-end_message
 
diff --git a/railties/lib/rails/secrets.rb b/railties/lib/rails/secrets.rb
new file mode 100644
index 0000000000..30e3478c9b
--- /dev/null
+++ b/railties/lib/rails/secrets.rb
@@ -0,0 +1,106 @@
+# frozen_string_literal: true
+
+require "yaml"
+require "active_support/message_encryptor"
+require "active_support/core_ext/string/strip"
+
+module Rails
+  # Greatly inspired by Ara T. Howard's magnificent sekrets gem. 😘
+  class Secrets # :nodoc:
+    class MissingKeyError < RuntimeError
+      def initialize
+        super(<<-end_of_message.squish)
+          Missing encryption key to decrypt secrets with.
+          Ask your team for your master key and put it in ENV["RAILS_MASTER_KEY"]
+        end_of_message
+      end
+    end
+
+    @cipher = "aes-128-gcm"
+    @root = File # Wonky, but ensures `join` uses the current directory.
+
+    class << self
+      attr_writer :root
+
+      def parse(paths, env:)
+        paths.each_with_object(Hash.new) do |path, all_secrets|
+          require "erb"
+
+          secrets = YAML.load(ERB.new(preprocess(path)).result) || {}
+          all_secrets.merge!(secrets["shared"].deep_symbolize_keys) if secrets["shared"]
+          all_secrets.merge!(secrets[env].deep_symbolize_keys) if secrets[env]
+        end
+      end
+
+      def key
+        ENV["RAILS_MASTER_KEY"] || read_key_file || handle_missing_key
+      end
+
+      def encrypt(data)
+        encryptor.encrypt_and_sign(data)
+      end
+
+      def decrypt(data)
+        encryptor.decrypt_and_verify(data)
+      end
+
+      def read
+        decrypt(IO.binread(path))
+      end
+
+      def write(contents)
+        IO.binwrite("#{path}.tmp", encrypt(contents))
+        FileUtils.mv("#{path}.tmp", path)
+      end
+
+      def read_for_editing(&block)
+        writing(read, &block)
+      end
+
+      private
+        def handle_missing_key
+          raise MissingKeyError
+        end
+
+        def read_key_file
+          if File.exist?(key_path)
+            IO.binread(key_path).strip
+          end
+        end
+
+        def key_path
+          @root.join("config", "secrets.yml.key")
+        end
+
+        def path
+          @root.join("config", "secrets.yml.enc").to_s
+        end
+
+        def preprocess(path)
+          if path.end_with?(".enc")
+            decrypt(IO.binread(path))
+          else
+            IO.read(path)
+          end
+        end
+
+        def writing(contents)
+          tmp_file = "#{File.basename(path)}.#{Process.pid}"
+          tmp_path = File.join(Dir.tmpdir, tmp_file)
+          IO.binwrite(tmp_path, contents)
+
+          yield tmp_path
+
+          updated_contents = IO.binread(tmp_path)
+
+          write(updated_contents) if updated_contents != contents
+        ensure
+          FileUtils.rm(tmp_path) if File.exist?(tmp_path)
+        end
+
+        def encryptor
+          @encryptor ||= ActiveSupport::MessageEncryptor.new([ key ].pack("H*"), cipher: @cipher)
+        end
+    end
+  end
+end
diff --git a/railties/lib/rails/source_annotation_extractor.rb b/railties/lib/rails/source_annotation_extractor.rb
index 8dd87b6cc5..1db6c98537 100644
--- a/railties/lib/rails/source_annotation_extractor.rb
+++ b/railties/lib/rails/source_annotation_extractor.rb
@@ -1,9 +1,11 @@
+# frozen_string_literal: true
+
 # Implements the logic behind the rake tasks for annotations like
 #
-#   rake notes
-#   rake notes:optimize
+#   rails notes
+#   rails notes:optimize
 #
-# and friends. See <tt>rake -T notes</tt> and <tt>railties/lib/rails/tasks/annotations.rake</tt>.
+# and friends. See <tt>rails -T notes</tt> and <tt>railties/lib/rails/tasks/annotations.rake</tt>.
 #
 # Annotation objects are triplets <tt>:line</tt>, <tt>:tag</tt>, <tt>:text</tt> that
 # represent the line where the annotation lives, its tag, and its text. Note
@@ -13,9 +15,15 @@
 # start with the tag optionally followed by a colon. Everything up to the end
 # of the line (or closing ERB comment tag) is considered to be their text.
 class SourceAnnotationExtractor
-  class Annotation < Struct.new(:line, :tag, :text)
+  Annotation = Struct.new(:line, :tag, :text) do
     def self.directories
-      @@directories ||= %w(app config db lib test) + (ENV['SOURCE_ANNOTATION_DIRECTORIES'] || '').split(',')
+      @@directories ||= %w(app config db lib test) + (ENV["SOURCE_ANNOTATION_DIRECTORIES"] || "").split(",")
+    end
+
+    # Registers additional directories to be included
+    #   SourceAnnotationExtractor::Annotation.register_directories("spec", "another")
+    def self.register_directories(*dirs)
+      directories.push(*dirs)
     end
 
     def self.extensions
@@ -38,8 +46,8 @@ class SourceAnnotationExtractor
     #
     # If +options+ has a flag <tt>:tag</tt> the tag is shown as in the example above.
     # Otherwise the string contains just line and text.
-    def to_s(options={})
-      s = "[#{line.to_s.rjust(options[:indent])}] "
+    def to_s(options = {})
+      s = "[#{line.to_s.rjust(options[:indent])}] ".dup
       s << "[#{tag}] " if options[:tag]
       s << text
     end
@@ -60,7 +68,7 @@ class SourceAnnotationExtractor
   # See <tt>#find_in</tt> for a list of file extensions that will be taken into account.
   #
   # This class method is the single entry point for the rake tasks.
-  def self.enumerate(tag, options={})
+  def self.enumerate(tag, options = {})
     extractor = new(tag)
     dirs = options.delete(:dirs) || Annotation.directories
     extractor.display(extractor.find(dirs), options)
@@ -110,7 +118,7 @@ class SourceAnnotationExtractor
   # Otherwise it returns an empty hash.
   def extract_annotations_from(file, pattern)
     lineno = 0
-    result = File.readlines(file).inject([]) do |list, line|
+    result = File.readlines(file, encoding: Encoding::BINARY).inject([]) do |list, line|
       lineno += 1
       next list unless line =~ pattern
       list << Annotation.new(lineno, $1, $2)
@@ -120,7 +128,7 @@ class SourceAnnotationExtractor
 
   # Prints the mapping from filenames to annotations in +results+ ordered by filename.
   # The +options+ hash is passed to each annotation's +to_s+.
-  def display(results, options={})
+  def display(results, options = {})
     options[:indent] = results.flat_map { |f, a| a.map(&:line) }.max.to_s.size
     results.keys.sort.each do |file|
       puts "#{file}:"
diff --git a/railties/lib/rails/tasks.rb b/railties/lib/rails/tasks.rb
index d3e33584d7..2f644a20c9 100644
--- a/railties/lib/rails/tasks.rb
+++ b/railties/lib/rails/tasks.rb
@@ -1,4 +1,6 @@
-require 'rake'
+# frozen_string_literal: true
+
+require "rake"
 
 # Load Rails Rakefile extensions
 %w(
@@ -12,8 +14,9 @@ require 'rake'
   restart
   routes
   tmp
+  yarn
 ).tap { |arr|
-  arr << 'statistics' if Rake.application.current_scope.empty?
+  arr << "statistics" if Rake.application.current_scope.empty?
 }.each do |task|
   load "rails/tasks/#{task}.rake"
 end
diff --git a/railties/lib/rails/tasks/annotations.rake b/railties/lib/rails/tasks/annotations.rake
index 386ecf44be..93bc66e2db 100644
--- a/railties/lib/rails/tasks/annotations.rake
+++ b/railties/lib/rails/tasks/annotations.rake
@@ -1,4 +1,6 @@
-require 'rails/source_annotation_extractor'
+# frozen_string_literal: true
+
+require "rails/source_annotation_extractor"
 
 desc "Enumerate all annotations (use notes:optimize, :fixme, :todo for focus)"
 task :notes do
@@ -15,6 +17,6 @@ namespace :notes do
 
   desc "Enumerate a custom annotation, specify with ANNOTATION=CUSTOM"
   task :custom do
-    SourceAnnotationExtractor.enumerate ENV['ANNOTATION']
+    SourceAnnotationExtractor.enumerate ENV["ANNOTATION"]
   end
-end
\ No newline at end of file
+end
diff --git a/railties/lib/rails/tasks/dev.rake b/railties/lib/rails/tasks/dev.rake
index d2ceaacc0c..5aea6f7dc5 100644
--- a/railties/lib/rails/tasks/dev.rake
+++ b/railties/lib/rails/tasks/dev.rake
@@ -1,7 +1,9 @@
-require 'rails/dev_caching'
+# frozen_string_literal: true
+
+require "rails/dev_caching"
 
 namespace :dev do
-  desc 'Toggle development mode caching on/off'
+  desc "Toggle development mode caching on/off"
   task :cache do
     Rails::DevCaching.enable_by_file
   end
diff --git a/railties/lib/rails/tasks/engine.rake b/railties/lib/rails/tasks/engine.rake
index e678103f63..8d77904210 100644
--- a/railties/lib/rails/tasks/engine.rake
+++ b/railties/lib/rails/tasks/engine.rake
@@ -1,8 +1,21 @@
+# frozen_string_literal: true
+
 task "load_app" do
   namespace :app do
     load APP_RAKEFILE
+
+    desc "Update some initially generated files"
+    task update: [ "update:bin" ]
+
+    namespace :update do
+      require "rails/engine/updater"
+      # desc "Adds new executables to the engine bin/ directory"
+      task :bin do
+        Rails::Engine::Updater.run(:create_bin_files)
+      end
+    end
   end
-  task :environment => "app:environment"
+  task environment: "app:environment"
 
   if !defined?(ENGINE_ROOT) || !ENGINE_ROOT
     ENGINE_ROOT = find_engine_path(APP_RAKEFILE)
@@ -26,11 +39,11 @@ namespace :db do
   desc "Display status of migrations"
   app_task "migrate:status"
 
-  desc 'Create the database from config/database.yml for the current Rails.env (use db:create:all to create all databases in the config)'
+  desc "Create the database from config/database.yml for the current Rails.env (use db:create:all to create all databases in the config)"
   app_task "create"
   app_task "create:all"
 
-  desc 'Drops the database for the current Rails.env (use db:drop:all to drop all databases)'
+  desc "Drops the database for the current Rails.env (use db:drop:all to drop all databases)"
   app_task "drop"
   app_task "drop:all"
 
@@ -40,7 +53,7 @@ namespace :db do
   desc "Rolls the schema back to the previous version (specify steps w/ STEP=n)."
   app_task "rollback"
 
-  desc "Create a db/schema.rb file that can be portably used against any DB supported by Active Record"
+  desc "Create a db/schema.rb file that can be portably used against any database supported by Active Record"
   app_task "schema:dump"
 
   desc "Load a schema.rb file into the database"
@@ -49,7 +62,7 @@ namespace :db do
   desc "Load the seed data from db/seeds.rb"
   app_task "seed"
 
-  desc "Create the database, load the schema, and initialize with the seed data (use db:reset to also drop the db first)"
+  desc "Create the database, load the schema, and initialize with the seed data (use db:reset to also drop the database first)"
   app_task "setup"
 
   desc "Dump the database structure to an SQL file"
@@ -57,6 +70,9 @@ namespace :db do
 
   desc "Retrieves the current schema version number"
   app_task "version"
+
+  # desc 'Load the test schema'
+  app_task "test:prepare"
 end
 
 def find_engine_path(path)
@@ -65,7 +81,7 @@ def find_engine_path(path)
   if Rails::Engine.find(path)
     path
   else
-    find_engine_path(File.expand_path('..', path))
+    find_engine_path(File.expand_path("..", path))
   end
 end
 
diff --git a/railties/lib/rails/tasks/framework.rake b/railties/lib/rails/tasks/framework.rake
index 51d9daaaa9..7dfcd14bd0 100644
--- a/railties/lib/rails/tasks/framework.rake
+++ b/railties/lib/rails/tasks/framework.rake
@@ -1,24 +1,24 @@
-require 'active_support/deprecation'
+# frozen_string_literal: true
 
 namespace :app do
   desc "Update configs and some other initially generated files (or use just update:configs or update:bin)"
-  task update: [ "update:configs", "update:bin" ]
+  task update: [ "update:configs", "update:bin", "update:upgrade_guide_info" ]
 
   desc "Applies the template supplied by LOCATION=(/path/to/template) or URL"
   task template: :environment do
     template = ENV["LOCATION"]
     raise "No LOCATION value given. Please set LOCATION either as path to a file or a URL" if template.blank?
     template = File.expand_path(template) if template !~ %r{\A[A-Za-z][A-Za-z0-9+\-\.]*://}
-    require 'rails/generators'
-    require 'rails/generators/rails/app/app_generator'
-    generator = Rails::Generators::AppGenerator.new [Rails.root], {}, destination_root: Rails.root
+    require "rails/generators"
+    require "rails/generators/rails/app/app_generator"
+    generator = Rails::Generators::AppGenerator.new [Rails.root], {}, { destination_root: Rails.root }
     generator.apply template, verbose: false
   end
 
   namespace :templates do
     # desc "Copy all the templates from rails to the application directory for customization. Already existing local copies will be overwritten"
     task :copy do
-      generators_lib = File.expand_path("../../generators", __FILE__)
+      generators_lib = File.expand_path("../generators", __dir__)
       project_templates = "#{Rails.root}/lib/templates"
 
       default_templates = { "erb"   => %w{controller mailer scaffold},
@@ -38,46 +38,21 @@ namespace :app do
   end
 
   namespace :update do
-    class RailsUpdate
-      def self.invoke_from_app_generator(method)
-        app_generator.send(method)
-      end
-
-      def self.app_generator
-        @app_generator ||= begin
-          require 'rails/generators'
-          require 'rails/generators/rails/app/app_generator'
-          gen = Rails::Generators::AppGenerator.new ["rails"],
-                                                    { api: !!Rails.application.config.api_only, update: true },
-                                                    destination_root: Rails.root
-          File.exist?(Rails.root.join("config", "application.rb")) ?
-            gen.send(:app_const) : gen.send(:valid_const?)
-          gen
-        end
-      end
-    end
+    require "rails/app_updater"
 
     # desc "Update config/boot.rb from your current rails install"
     task :configs do
-      RailsUpdate.invoke_from_app_generator :create_boot_file
-      RailsUpdate.invoke_from_app_generator :update_config_files
+      Rails::AppUpdater.invoke_from_app_generator :create_boot_file
+      Rails::AppUpdater.invoke_from_app_generator :update_config_files
     end
 
     # desc "Adds new executables to the application bin/ directory"
     task :bin do
-      RailsUpdate.invoke_from_app_generator :create_bin_files
+      Rails::AppUpdater.invoke_from_app_generator :update_bin_files
     end
-  end
-end
 
-namespace :rails do
-  %i(update template templates:copy update:configs update:bin).each do |task_name|
-    task "#{task_name}" do
-      ActiveSupport::Deprecation.warn(<<-MSG.squish)
-        Running #{task_name} with the rails: namespace is deprecated in favor of app: namespace.
-        Run bin/rails app:#{task_name} instead.
-      MSG
-      Rake.application.invoke_task("app:#{task_name}")
+    task :upgrade_guide_info do
+      Rails::AppUpdater.invoke_from_app_generator :display_upgrade_guide_info
     end
   end
 end
diff --git a/railties/lib/rails/tasks/initializers.rake b/railties/lib/rails/tasks/initializers.rake
index 2968b5cb53..ae85cb0f86 100644
--- a/railties/lib/rails/tasks/initializers.rake
+++ b/railties/lib/rails/tasks/initializers.rake
@@ -1,6 +1,8 @@
+# frozen_string_literal: true
+
 desc "Print out all defined initializers in the order they are invoked by Rails."
 task initializers: :environment do
   Rails.application.initializers.tsort_each do |initializer|
-    puts initializer.name
+    puts "#{initializer.context_class}.#{initializer.name}"
   end
 end
diff --git a/railties/lib/rails/tasks/log.rake b/railties/lib/rails/tasks/log.rake
index 073f235ec5..e219277d23 100644
--- a/railties/lib/rails/tasks/log.rake
+++ b/railties/lib/rails/tasks/log.rake
@@ -1,9 +1,11 @@
+# frozen_string_literal: true
+
 namespace :log do
-  
-  ## 
+
+  ##
   # Truncates all/specified log files
-  # ENV['LOGS'] 
-  #   - defaults to standard environment log files i.e. 'development,test,production'
+  # ENV['LOGS']
+  #   - defaults to all environments log files i.e. 'development,test,production'
   #   - ENV['LOGS']=all truncates all files i.e. log/*.log
   #   - ENV['LOGS']='test,development' truncates only specified files
   desc "Truncates all/specified *.log files in log/ to zero bytes (specify which logs with LOGS=test,development)"
@@ -14,23 +16,27 @@ namespace :log do
   end
 
   def log_files
-    if ENV['LOGS'] == 'all'
+    if ENV["LOGS"] == "all"
       FileList["log/*.log"]
-    elsif ENV['LOGS']
-      log_files_to_truncate(ENV['LOGS'])
+    elsif ENV["LOGS"]
+      log_files_to_truncate(ENV["LOGS"])
     else
-      log_files_to_truncate("development,test,production")
+      log_files_to_truncate(all_environments.join(","))
     end
   end
 
   def log_files_to_truncate(envs)
-    envs.split(',')
+    envs.split(",")
         .map    { |file| "log/#{file.strip}.log" }
         .select { |file| File.exist?(file) }
   end
-  
+
   def clear_log_file(file)
     f = File.open(file, "w")
     f.close
   end
+
+  def all_environments
+    Dir["config/environments/*.rb"].map { |fname| File.basename(fname, ".*") }
+  end
 end
diff --git a/railties/lib/rails/tasks/middleware.rake b/railties/lib/rails/tasks/middleware.rake
index 31e961b483..3a7f86fdcb 100644
--- a/railties/lib/rails/tasks/middleware.rake
+++ b/railties/lib/rails/tasks/middleware.rake
@@ -1,4 +1,6 @@
-desc 'Prints out your Rack middleware stack'
+# frozen_string_literal: true
+
+desc "Prints out your Rack middleware stack"
 task middleware: :environment do
   Rails.configuration.middleware.each do |middleware|
     puts "use #{middleware.inspect}"
diff --git a/railties/lib/rails/tasks/misc.rake b/railties/lib/rails/tasks/misc.rake
index e6b13cc077..e7786aa622 100644
--- a/railties/lib/rails/tasks/misc.rake
+++ b/railties/lib/rails/tasks/misc.rake
@@ -1,16 +1,18 @@
-desc 'Generate a cryptographically secure secret key (this is typically used to generate a secret for cookie sessions).'
+# frozen_string_literal: true
+
+desc "Generate a cryptographically secure secret key (this is typically used to generate a secret for cookie sessions)."
 task :secret do
-  require 'securerandom'
+  require "securerandom"
   puts SecureRandom.hex(64)
 end
 
-desc 'List versions of all Rails frameworks and the environment'
+desc "List versions of all Rails frameworks and the environment"
 task about: :environment do
   puts Rails::Info
 end
 
 namespace :time do
-  desc 'List all time zones, list by two-letter country code (`rails time:zones[US]`), or list by UTC offset (`rails time:zones[-8]`)'
+  desc "List all time zones, list by two-letter country code (`rails time:zones[US]`), or list by UTC offset (`rails time:zones[-8]`)"
   task :zones, :country_or_offset do |t, args|
     zones, offset = ActiveSupport::TimeZone.all, nil
 
@@ -38,8 +40,8 @@ namespace :time do
 
     # desc 'Displays names of time zones recognized by the Rails TimeZone class with the same offset as the system local time'
     task :local do
-      require 'active_support'
-      require 'active_support/time'
+      require "active_support"
+      require "active_support/time"
 
       jan_offset = Time.now.beginning_of_year.utc_offset
       jul_offset = Time.now.beginning_of_year.change(month: 7).utc_offset
@@ -49,12 +51,12 @@ namespace :time do
     end
 
     # to find UTC -06:00 zones, OFFSET can be set to either -6, -6:00 or 21600
-    def build_time_zone_list(zones, offset = ENV['OFFSET'])
-      require 'active_support'
-      require 'active_support/time'
+    def build_time_zone_list(zones, offset = ENV["OFFSET"])
+      require "active_support"
+      require "active_support/time"
       if offset
         offset = if offset.to_s.match(/(\+|-)?(\d+):(\d+)/)
-          sign = $1 == '-' ? -1 : 1
+          sign = $1 == "-" ? -1 : 1
           hours, minutes = $2.to_f, $3.to_f
           ((hours * 3600) + (minutes.to_f * 60)) * sign
         elsif offset.to_f.abs <= 13
diff --git a/railties/lib/rails/tasks/restart.rake b/railties/lib/rails/tasks/restart.rake
index 3f98cbe51f..074e3e89a1 100644
--- a/railties/lib/rails/tasks/restart.rake
+++ b/railties/lib/rails/tasks/restart.rake
@@ -1,8 +1,9 @@
-desc 'Restart app by touching tmp/restart.txt'
+# frozen_string_literal: true
+
+desc "Restart app by touching tmp/restart.txt"
 task :restart do
   verbose(false) do
-    mkdir_p 'tmp'
-    touch 'tmp/restart.txt'
-    rm_f 'tmp/pids/server.pid'
+    mkdir_p "tmp"
+    touch "tmp/restart.txt"
   end
 end
diff --git a/railties/lib/rails/tasks/routes.rake b/railties/lib/rails/tasks/routes.rake
index ff7233cae9..403286d280 100644
--- a/railties/lib/rails/tasks/routes.rake
+++ b/railties/lib/rails/tasks/routes.rake
@@ -1,21 +1,14 @@
-require 'active_support/deprecation'
-require 'active_support/core_ext/string/strip' # for strip_heredoc
-require 'optparse'
+# frozen_string_literal: true
 
-desc 'Print out all defined routes in match order, with names. Target specific controller with -c option, or grep routes using -g option'
+require "optparse"
+
+desc "Print out all defined routes in match order, with names. Target specific controller with -c option, or grep routes using -g option"
 task routes: :environment do
   all_routes = Rails.application.routes.routes
-  require 'action_dispatch/routing/inspector'
+  require "action_dispatch/routing/inspector"
   inspector = ActionDispatch::Routing::RoutesInspector.new(all_routes)
-  if ARGV.any?{ |argv| argv.start_with? 'CONTROLLER' }
-    puts <<-eow.strip_heredoc
-      Passing `CONTROLLER` to `bin/rails routes` is deprecated and will be removed in Rails 5.1.
-      Please use `bin/rails routes -c controller_name` instead.
-    eow
-  end
 
   routes_filter = nil
-  routes_filter = { controller: ENV['CONTROLLER'] } if ENV['CONTROLLER']
 
   OptionParser.new do |opts|
     opts.banner = "Usage: rails routes [options]"
diff --git a/railties/lib/rails/tasks/statistics.rake b/railties/lib/rails/tasks/statistics.rake
index 3e40d3b037..594db91eec 100644
--- a/railties/lib/rails/tasks/statistics.rake
+++ b/railties/lib/rails/tasks/statistics.rake
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 # While global constants are bad, many 3rd party tools depend on this one (e.g
 # rspec-rails & cucumber-rails). So a deprecation warning is needed if we want
 # to remove it.
@@ -8,9 +10,8 @@ STATS_DIRECTORIES = [
   %w(Models             app/models),
   %w(Mailers            app/mailers),
   %w(Channels           app/channels),
-  %w(Javascripts        app/assets/javascripts),
+  %w(JavaScripts        app/assets/javascripts),
   %w(Libraries          lib/),
-  %w(Tasks              lib/tasks),
   %w(APIs               app/apis),
   %w(Controller\ tests  test/controllers),
   %w(Helper\ tests      test/helpers),
@@ -18,12 +19,13 @@ STATS_DIRECTORIES = [
   %w(Mailer\ tests      test/mailers),
   %w(Job\ tests         test/jobs),
   %w(Integration\ tests test/integration),
+  %w(System\ tests      test/system),
 ].collect do |name, dir|
   [ name, "#{File.dirname(Rake.application.rakefile_location)}/#{dir}" ]
 end.select { |name, dir| File.directory?(dir) }
 
 desc "Report code statistics (KLOCs, etc) from the application or engine"
 task :stats do
-  require 'rails/code_statistics'
+  require "rails/code_statistics"
   CodeStatistics.new(*STATS_DIRECTORIES).to_s
 end
diff --git a/railties/lib/rails/tasks/tmp.rake b/railties/lib/rails/tasks/tmp.rake
index c74a17a0ca..7340b41ee4 100644
--- a/railties/lib/rails/tasks/tmp.rake
+++ b/railties/lib/rails/tasks/tmp.rake
@@ -1,11 +1,13 @@
+# frozen_string_literal: true
+
 namespace :tmp do
-  desc "Clear cache and socket files from tmp/ (narrow w/ tmp:cache:clear, tmp:sockets:clear)"
-  task clear: ["tmp:cache:clear", "tmp:sockets:clear"]
+  desc "Clear cache, socket and screenshot files from tmp/ (narrow w/ tmp:cache:clear, tmp:sockets:clear, tmp:screenshots:clear)"
+  task clear: ["tmp:cache:clear", "tmp:sockets:clear", "tmp:screenshots:clear"]
 
-  tmp_dirs = [ 'tmp/cache',
-               'tmp/sockets',
-               'tmp/pids',
-               'tmp/cache/assets' ]
+  tmp_dirs = [ "tmp/cache",
+               "tmp/sockets",
+               "tmp/pids",
+               "tmp/cache/assets" ]
 
   tmp_dirs.each { |d| directory d }
 
@@ -15,21 +17,28 @@ namespace :tmp do
   namespace :cache do
     # desc "Clears all files and directories in tmp/cache"
     task :clear do
-      rm_rf Dir['tmp/cache/[^.]*'], verbose: false
+      rm_rf Dir["tmp/cache/[^.]*"], verbose: false
     end
   end
 
   namespace :sockets do
     # desc "Clears all files in tmp/sockets"
     task :clear do
-      rm Dir['tmp/sockets/[^.]*'], verbose: false
+      rm Dir["tmp/sockets/[^.]*"], verbose: false
     end
   end
 
   namespace :pids do
     # desc "Clears all files in tmp/pids"
     task :clear do
-      rm Dir['tmp/pids/[^.]*'], verbose: false
+      rm Dir["tmp/pids/[^.]*"], verbose: false
+    end
+  end
+
+  namespace :screenshots do
+    # desc "Clears all files in tmp/screenshots"
+    task :clear do
+      rm Dir["tmp/screenshots/[^.]*"], verbose: false
     end
   end
 end
diff --git a/railties/lib/rails/tasks/yarn.rake b/railties/lib/rails/tasks/yarn.rake
new file mode 100644
index 0000000000..48da7ffc51
--- /dev/null
+++ b/railties/lib/rails/tasks/yarn.rake
@@ -0,0 +1,13 @@
+# frozen_string_literal: true
+
+namespace :yarn do
+  desc "Install all JavaScript dependencies as specified via Yarn"
+  task :install do
+    system("./bin/yarn install --no-progress --production")
+  end
+end
+
+# Run Yarn prior to Sprockets assets precompilation, so dependencies are available for use.
+if Rake::Task.task_defined?("assets:precompile")
+  Rake::Task["assets:precompile"].enhance [ "yarn:install" ]
+end
diff --git a/railties/lib/rails/templates/rails/mailers/email.html.erb b/railties/lib/rails/templates/rails/mailers/email.html.erb
index fed96fbc85..89c1129f90 100644
--- a/railties/lib/rails/templates/rails/mailers/email.html.erb
+++ b/railties/lib/rails/templates/rails/mailers/email.html.erb
@@ -88,15 +88,18 @@
     <% unless @email.attachments.nil? || @email.attachments.empty? %>
       <dt>Attachments:</dt>
       <dd>
-        <%= @email.attachments.map { |a| a.respond_to?(:original_filename) ? a.original_filename : a.filename }.join(', ') %>
+        <% @email.attachments.each do |a| %>
+          <% filename = a.respond_to?(:original_filename) ? a.original_filename : a.filename %>
+          <%= link_to filename, "data:application/octet-stream;charset=utf-8;base64,#{Base64.encode64(a.body.to_s)}", download: filename %>
+        <% end %>
       </dd>
     <% end %>
 
     <% if @email.multipart? %>
       <dd>
         <select onchange="formatChanged(this);">
-          <option <%= request.format == Mime[:html] ? 'selected' : '' %> value="?part=text%2Fhtml">View as HTML email</option>
-          <option <%= request.format == Mime[:text] ? 'selected' : '' %> value="?part=text%2Fplain">View as plain-text email</option>
+          <option <%= request.format == Mime[:html] ? 'selected' : '' %> value="?<%= part_query('text/html') %>">View as HTML email</option>
+          <option <%= request.format == Mime[:text] ? 'selected' : '' %> value="?<%= part_query('text/plain') %>">View as plain-text email</option>
         </select>
       </dd>
     <% end %>
@@ -104,7 +107,7 @@
 </header>
 
 <% if @part && @part.mime_type %>
-  <iframe seamless name="messageBody" src="?part=<%= Rack::Utils.escape(@part.mime_type) %>"></iframe>
+  <iframe seamless name="messageBody" src="?<%= part_query(@part.mime_type) %>"></iframe>
 <% else %>
   <p>
     You are trying to preview an email that does not have any content.
diff --git a/railties/lib/rails/templates/rails/welcome/index.html.erb b/railties/lib/rails/templates/rails/welcome/index.html.erb
index 5cdb7e6a20..5a82bf913c 100644
--- a/railties/lib/rails/templates/rails/welcome/index.html.erb
+++ b/railties/lib/rails/templates/rails/welcome/index.html.erb
@@ -26,18 +26,28 @@
     p { font-family: monospace; }
 
     .container {
-      width: 960px;
+      max-width: 960px;
       margin: 0 auto 40px;
       overflow: hidden;
     }
 
-
     section {
       margin: 0 auto 2rem;
       padding: 1rem 0 0;
-      width: 700px;
       text-align: center;
     }
+
+    @media only screen and (max-width: 500px) {
+      h1 { font-size: 2rem; }
+
+      .version { font-size: 1.1rem; }
+    }
+
+    .welcome {
+      width: 600px;
+      max-width: 100%;
+      height: auto;
+    }
   </style>
 </head>
 
@@ -52,7 +62,7 @@
 
       <h1>Yay! You&rsquo;re on Rails!</h1>
 
-      <img alt="Welcome" width="600" height="350" 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" 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+      <img alt="Welcome" class="welcome" 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" />
 
       <p class="version">
         <strong>Rails version:</strong> <%= Rails.version %><br />
diff --git a/railties/lib/rails/test_help.rb b/railties/lib/rails/test_help.rb
index 5cc1b5b219..76c28ac85e 100644
--- a/railties/lib/rails/test_help.rb
+++ b/railties/lib/rails/test_help.rb
@@ -1,32 +1,38 @@
+# frozen_string_literal: true
+
 # Make double-sure the RAILS_ENV is not set to production,
 # so fixtures aren't loaded into that environment
 abort("Abort testing: Your Rails environment is running in production mode!") if Rails.env.production?
 
-require "rails/test_unit/minitest_plugin"
-require 'active_support/test_case'
-require 'action_controller'
-require 'action_controller/test_case'
-require 'action_dispatch/testing/integration'
-require 'rails/generators/test_case'
+require "active_support/test_case"
+require "action_controller"
+require "action_controller/test_case"
+require "action_dispatch/testing/integration"
+require "rails/generators/test_case"
 
-require 'active_support/testing/autorun'
+require "active_support/testing/autorun"
 
 if defined?(ActiveRecord::Base)
-  ActiveRecord::Migration.maintain_test_schema!
+  begin
+    ActiveRecord::Migration.maintain_test_schema!
+  rescue ActiveRecord::PendingMigrationError => e
+    puts e.to_s.strip
+    exit 1
+  end
 
-  class ActiveSupport::TestCase
-    include ActiveRecord::TestFixtures
-    self.fixture_path = "#{Rails.root}/test/fixtures/"
-    self.file_fixture_path = self.fixture_path + "files"
+  module ActiveSupport
+    class TestCase
+      include ActiveRecord::TestFixtures
+      self.fixture_path = "#{Rails.root}/test/fixtures/"
+      self.file_fixture_path = fixture_path + "files"
+    end
   end
 
   ActionDispatch::IntegrationTest.fixture_path = ActiveSupport::TestCase.fixture_path
-
-  def create_fixtures(*fixture_set_names, &block)
-    FixtureSet.create_fixtures(ActiveSupport::TestCase.fixture_path, fixture_set_names, {}, &block)
-  end
 end
 
+# :enddoc:
+
 class ActionController::TestCase
   def before_setup # :nodoc:
     @routes = Rails.application.routes
diff --git a/railties/lib/rails/test_unit/line_filtering.rb b/railties/lib/rails/test_unit/line_filtering.rb
index dd9732bb12..f8ca77fe4a 100644
--- a/railties/lib/rails/test_unit/line_filtering.rb
+++ b/railties/lib/rails/test_unit/line_filtering.rb
@@ -1,78 +1,13 @@
-require 'method_source'
+# frozen_string_literal: true
+
+require "rails/test_unit/runner"
 
 module Rails
   module LineFiltering # :nodoc:
     def run(reporter, options = {})
-      if options[:patterns] && options[:patterns].any? { |p| p =~ /:\d+/ }
-        options[:filter] = \
-          CompositeFilter.new(self, options[:filter], options[:patterns])
-      end
+      options[:filter] = Rails::TestUnit::Runner.compose_filter(self, options[:filter])
 
       super
     end
   end
-
-  class CompositeFilter # :nodoc:
-    attr_reader :named_filter
-
-    def initialize(runnable, filter, patterns)
-      @runnable = runnable
-      @named_filter = derive_named_filter(filter)
-      @filters = [ @named_filter, *derive_line_filters(patterns) ].compact
-    end
-
-    # Minitest uses === to find matching filters.
-    def ===(method)
-      @filters.any? { |filter| filter === method }
-    end
-
-    private
-      def derive_named_filter(filter)
-        if filter.respond_to?(:named_filter)
-          filter.named_filter
-        elsif filter =~ %r%/(.*)/% # Regexp filtering copied from Minitest.
-          Regexp.new $1
-        elsif filter.is_a?(String)
-          filter
-        end
-      end
-
-      def derive_line_filters(patterns)
-        patterns.flat_map do |file_and_line|
-          file, *lines = file_and_line.split(':')
-
-          if lines.empty?
-            Filter.new(@runnable, file, nil) if file
-          else
-            lines.map { |line| Filter.new(@runnable, file, line) }
-          end
-        end
-      end
-  end
-
-  class Filter # :nodoc:
-    def initialize(runnable, file, line)
-      @runnable, @file = runnable, File.expand_path(file)
-      @line = line.to_i if line
-    end
-
-    def ===(method)
-      return unless @runnable.method_defined?(method)
-
-      if @line
-        test_file, test_range = definition_for(@runnable.instance_method(method))
-        test_file == @file && test_range.include?(@line)
-      else
-        @runnable.instance_method(method).source_location.first == @file
-      end
-    end
-
-    private
-      def definition_for(method)
-        file, start_line = method.source_location
-        end_line = method.source.count("\n") + start_line - 1
-
-        return file, start_line..end_line
-      end
-  end
 end
diff --git a/railties/lib/rails/test_unit/minitest_plugin.rb b/railties/lib/rails/test_unit/minitest_plugin.rb
deleted file mode 100644
index 076ab536be..0000000000
--- a/railties/lib/rails/test_unit/minitest_plugin.rb
+++ /dev/null
@@ -1,98 +0,0 @@
-require "active_support/core_ext/module/attribute_accessors"
-require "rails/test_unit/reporter"
-require "rails/test_unit/test_requirer"
-require 'shellwords'
-
-module Minitest
-  class SuppressedSummaryReporter < SummaryReporter
-    # Disable extra failure output after a run if output is inline.
-    def aggregated_results
-      super unless options[:output_inline]
-    end
-  end
-
-  def self.plugin_rails_options(opts, options)
-    executable = ::Rails::TestUnitReporter.executable
-    opts.separator ""
-    opts.separator "Usage: #{executable} [options] [files or directories]"
-    opts.separator "You can run a single test by appending a line number to a filename:"
-    opts.separator ""
-    opts.separator "    #{executable} test/models/user_test.rb:27"
-    opts.separator ""
-    opts.separator "You can run multiple files and directories at the same time:"
-    opts.separator ""
-    opts.separator "    #{executable} test/controllers test/integration/login_test.rb"
-    opts.separator ""
-    opts.separator "By default test failures and errors are reported inline during a run."
-    opts.separator ""
-
-    opts.separator "Rails options:"
-    opts.on("-e", "--environment ENV",
-            "Run tests in the ENV environment") do |env|
-      options[:environment] = env.strip
-    end
-
-    opts.on("-b", "--backtrace",
-            "Show the complete backtrace") do
-      options[:full_backtrace] = true
-    end
-
-    opts.on("-d", "--defer-output",
-            "Output test failures and errors after the test run") do
-      options[:output_inline] = false
-    end
-
-    opts.on("-f", "--fail-fast",
-            "Abort test run on first failure or error") do
-      options[:fail_fast] = true
-    end
-
-    opts.on("-c", "--[no-]color",
-            "Enable color in the output") do |value|
-      options[:color] = value
-    end
-
-    options[:color] = true
-    options[:output_inline] = true
-    options[:patterns] = defined?(@rake_patterns) ? @rake_patterns : opts.order!
-  end
-
-  # Running several Rake tasks in a single command would trip up the runner,
-  # as the patterns would also contain the other Rake tasks.
-  def self.rake_run(patterns) # :nodoc:
-    @rake_patterns = patterns
-    passed = run(Shellwords.split(ENV['TESTOPTS'] || ''))
-    exit passed unless passed
-    passed
-  end
-
-  # Owes great inspiration to test runner trailblazers like RSpec,
-  # minitest-reporters, maxitest and others.
-  def self.plugin_rails_init(options)
-    self.run_with_rails_extension = true
-
-    ENV["RAILS_ENV"] = options[:environment] || "test"
-
-    ::Rails::TestRequirer.require_files(options[:patterns]) unless run_with_autorun
-
-    unless options[:full_backtrace] || ENV["BACKTRACE"]
-      # Plugin can run without Rails loaded, check before filtering.
-      Minitest.backtrace_filter = ::Rails.backtrace_cleaner if ::Rails.respond_to?(:backtrace_cleaner)
-    end
-
-    # Replace progress reporter for colors.
-    reporter.reporters.delete_if { |reporter| reporter.kind_of?(SummaryReporter) || reporter.kind_of?(ProgressReporter) }
-    reporter << SuppressedSummaryReporter.new(options[:io], options)
-    reporter << ::Rails::TestUnitReporter.new(options[:io], options)
-  end
-
-  mattr_accessor(:run_with_autorun)         { false }
-  mattr_accessor(:run_with_rails_extension) { false }
-end
-
-# Put Rails as the first plugin minitest initializes so other plugins
-# can override or replace our default reporter setup.
-# Since minitest only loads plugins if its extensions are empty we have
-# to call `load_plugins` first.
-Minitest.load_plugins
-Minitest.extensions.unshift 'rails'
diff --git a/railties/lib/rails/test_unit/railtie.rb b/railties/lib/rails/test_unit/railtie.rb
index 511cee33bd..42b6daa3d1 100644
--- a/railties/lib/rails/test_unit/railtie.rb
+++ b/railties/lib/rails/test_unit/railtie.rb
@@ -1,7 +1,9 @@
-require 'rails/test_unit/line_filtering'
+# frozen_string_literal: true
+
+require "rails/test_unit/line_filtering"
 
 if defined?(Rake.application) && Rake.application.top_level_tasks.grep(/^(default$|test(:|$))/).any?
-  ENV['RAILS_ENV'] ||= 'test'
+  ENV["RAILS_ENV"] ||= Rake.application.options.show_tasks ? "development" : "test"
 end
 
 module Rails
@@ -11,10 +13,13 @@ module Rails
                                    fixture_replacement: nil
 
       c.integration_tool :test_unit
+      c.system_tests :test_unit
     end
 
     initializer "test_unit.line_filtering" do
-      ActiveSupport::TestCase.extend Rails::LineFiltering
+      ActiveSupport.on_load(:active_support_test_case) {
+        ActiveSupport::TestCase.extend Rails::LineFiltering
+      }
     end
 
     rake_tasks do
diff --git a/railties/lib/rails/test_unit/reporter.rb b/railties/lib/rails/test_unit/reporter.rb
index 4086d5b731..7d3164f1eb 100644
--- a/railties/lib/rails/test_unit/reporter.rb
+++ b/railties/lib/rails/test_unit/reporter.rb
@@ -1,10 +1,11 @@
+# frozen_string_literal: true
+
 require "active_support/core_ext/class/attribute"
 require "minitest"
 
 module Rails
   class TestUnitReporter < Minitest::StatisticsReporter
-    class_attribute :executable
-    self.executable = "bin/rails test"
+    class_attribute :executable, default: "bin/rails test"
 
     def record(result)
       super
@@ -50,7 +51,7 @@ module Rails
     end
 
     def relative_path_for(file)
-      file.sub(/^#{app_root}\/?/, '')
+      file.sub(/^#{app_root}\/?/, "")
     end
 
     private
@@ -68,11 +69,16 @@ module Rails
 
       def format_rerun_snippet(result)
         location, line = result.method(result.name).source_location
-        "#{self.executable} #{relative_path_for(location)}:#{line}"
+        "#{executable} #{relative_path_for(location)}:#{line}"
       end
 
       def app_root
-        @app_root ||= defined?(ENGINE_ROOT) ? ENGINE_ROOT : Rails.root
+        @app_root ||=
+          if defined?(ENGINE_ROOT)
+            ENGINE_ROOT
+          elsif Rails.respond_to?(:root)
+            Rails.root
+          end
       end
 
       def colored_output?
diff --git a/railties/lib/rails/test_unit/runner.rb b/railties/lib/rails/test_unit/runner.rb
new file mode 100644
index 0000000000..de5744c662
--- /dev/null
+++ b/railties/lib/rails/test_unit/runner.rb
@@ -0,0 +1,143 @@
+# frozen_string_literal: true
+
+require "shellwords"
+require "method_source"
+require "rake/file_list"
+require "active_support/core_ext/module/attribute_accessors"
+
+module Rails
+  module TestUnit
+    class Runner
+      mattr_reader :filters, default: []
+
+      class << self
+        def attach_before_load_options(opts)
+          opts.on("--warnings", "-w", "Run with Ruby warnings enabled") {}
+          opts.on("-e", "--environment ENV", "Run tests in the ENV environment") {}
+        end
+
+        def parse_options(argv)
+          # Perform manual parsing and cleanup since option parser raises on unknown options.
+          env_index = argv.index("--environment") || argv.index("-e")
+          if env_index
+            argv.delete_at(env_index)
+            environment = argv.delete_at(env_index).strip
+          end
+          ENV["RAILS_ENV"] = environment || "test"
+
+          w_index = argv.index("--warnings") || argv.index("-w")
+          $VERBOSE = argv.delete_at(w_index) if w_index
+        end
+
+        def rake_run(argv = [])
+          ARGV.replace Shellwords.split(ENV["TESTOPTS"] || "")
+
+          run(argv)
+        end
+
+        def run(argv = [])
+          load_tests(argv)
+
+          require "active_support/testing/autorun"
+        end
+
+        def load_tests(argv)
+          patterns = extract_filters(argv)
+
+          tests = Rake::FileList[patterns.any? ? patterns : "test/**/*_test.rb"]
+          tests.exclude("test/system/**/*") if patterns.empty?
+
+          tests.to_a.each { |path| require File.expand_path(path) }
+        end
+
+        def compose_filter(runnable, filter)
+          if filters.any? { |_, lines| lines.any? }
+            CompositeFilter.new(runnable, filter, filters)
+          else
+            filter
+          end
+        end
+
+        private
+          def extract_filters(argv)
+            # Extract absolute and relative paths but skip -n /.*/ regexp filters.
+            argv.select { |arg| arg =~ %r%^/?\w+/% && !arg.end_with?("/") }.map do |path|
+              case
+              when path =~ /(:\d+)+$/
+                file, *lines = path.split(":")
+                filters << [ file, lines ]
+                file
+              when Dir.exist?(path)
+                "#{path}/**/*_test.rb"
+              else
+                filters << [ path, [] ]
+                path
+              end
+            end
+          end
+      end
+    end
+
+    class CompositeFilter # :nodoc:
+      attr_reader :named_filter
+
+      def initialize(runnable, filter, patterns)
+        @runnable = runnable
+        @named_filter = derive_named_filter(filter)
+        @filters = [ @named_filter, *derive_line_filters(patterns) ].compact
+      end
+
+      # Minitest uses === to find matching filters.
+      def ===(method)
+        @filters.any? { |filter| filter === method }
+      end
+
+      private
+        def derive_named_filter(filter)
+          if filter.respond_to?(:named_filter)
+            filter.named_filter
+          elsif filter =~ %r%/(.*)/% # Regexp filtering copied from Minitest.
+            Regexp.new $1
+          elsif filter.is_a?(String)
+            filter
+          end
+        end
+
+        def derive_line_filters(patterns)
+          patterns.flat_map do |file, lines|
+            if lines.empty?
+              Filter.new(@runnable, file, nil) if file
+            else
+              lines.map { |line| Filter.new(@runnable, file, line) }
+            end
+          end
+        end
+    end
+
+    class Filter # :nodoc:
+      def initialize(runnable, file, line)
+        @runnable, @file = runnable, File.expand_path(file)
+        @line = line.to_i if line
+      end
+
+      def ===(method)
+        return unless @runnable.method_defined?(method)
+
+        if @line
+          test_file, test_range = definition_for(@runnable.instance_method(method))
+          test_file == @file && test_range.include?(@line)
+        else
+          @runnable.instance_method(method).source_location.first == @file
+        end
+      end
+
+      private
+        def definition_for(method)
+          file, start_line = method.source_location
+          end_line = method.source.count("\n") + start_line - 1
+
+          return file, start_line..end_line
+        end
+    end
+  end
+end
diff --git a/railties/lib/rails/test_unit/test_requirer.rb b/railties/lib/rails/test_unit/test_requirer.rb
deleted file mode 100644
index 8b211ce130..0000000000
--- a/railties/lib/rails/test_unit/test_requirer.rb
+++ /dev/null
@@ -1,28 +0,0 @@
-require 'active_support/core_ext/object/blank'
-require 'rake/file_list'
-
-module Rails
-  class TestRequirer # :nodoc:
-    class << self
-      def require_files(patterns)
-        patterns = expand_patterns(patterns)
-
-        Rake::FileList[patterns.compact.presence || 'test/**/*_test.rb'].to_a.each do |file|
-          require File.expand_path(file)
-        end
-      end
-
-      private
-        def expand_patterns(patterns)
-          patterns.map do |arg|
-            arg = arg.gsub(/(:\d+)+?$/, '')
-            if Dir.exist?(arg)
-              "#{arg}/**/*_test.rb"
-            else
-              arg
-            end
-          end
-        end
-    end
-  end
-end
diff --git a/railties/lib/rails/test_unit/testing.rake b/railties/lib/rails/test_unit/testing.rake
index 41921e43f3..32ac27a135 100644
--- a/railties/lib/rails/test_unit/testing.rake
+++ b/railties/lib/rails/test_unit/testing.rake
@@ -1,18 +1,20 @@
-gem 'minitest'
-require 'minitest'
-require 'rails/test_unit/minitest_plugin'
+# frozen_string_literal: true
+
+gem "minitest"
+require "minitest"
+require "rails/test_unit/runner"
 
 task default: :test
 
-desc "Runs all tests in test folder"
+desc "Runs all tests in test folder except system ones"
 task :test do
   $: << "test"
-  pattern = if ENV.key?('TEST')
-               ENV['TEST']
-             else
-               "test"
-             end
-  Minitest.rake_run([pattern])
+
+  if ENV.key?("TEST")
+    Rails::TestUnit::Runner.rake_run([ENV["TEST"]])
+  else
+    Rails::TestUnit::Runner.rake_run
+  end
 end
 
 namespace :test do
@@ -21,30 +23,36 @@ namespace :test do
     # If used with Active Record, this task runs before the database schema is synchronized.
   end
 
-  task :run => %w[test]
+  task run: %w[test]
 
   desc "Run tests quickly, but also reset db"
-  task :db => %w[db:test:prepare test]
+  task db: %w[db:test:prepare test]
 
   ["models", "helpers", "controllers", "mailers", "integration", "jobs"].each do |name|
     task name => "test:prepare" do
       $: << "test"
-      Minitest.rake_run(["test/#{name}"])
+      Rails::TestUnit::Runner.rake_run(["test/#{name}"])
     end
   end
 
-  task :generators => "test:prepare" do
+  task generators: "test:prepare" do
+    $: << "test"
+    Rails::TestUnit::Runner.rake_run(["test/lib/generators"])
+  end
+
+  task units: "test:prepare" do
     $: << "test"
-    Minitest.rake_run(["test/lib/generators"])
+    Rails::TestUnit::Runner.rake_run(["test/models", "test/helpers", "test/unit"])
   end
 
-  task :units => "test:prepare" do
+  task functionals: "test:prepare" do
     $: << "test"
-    Minitest.rake_run(["test/models", "test/helpers", "test/unit"])
+    Rails::TestUnit::Runner.rake_run(["test/controllers", "test/mailers", "test/functional"])
   end
 
-  task :functionals => "test:prepare" do
+  desc "Run system tests only"
+  task system: "test:prepare" do
     $: << "test"
-    Minitest.rake_run(["test/controllers", "test/mailers", "test/functional"])
+    Rails::TestUnit::Runner.rake_run(["test/system"])
   end
 end
diff --git a/railties/lib/rails/version.rb b/railties/lib/rails/version.rb
index df351c4238..ba6763a572 100644
--- a/railties/lib/rails/version.rb
+++ b/railties/lib/rails/version.rb
@@ -1,4 +1,6 @@
-require_relative 'gem_version'
+# frozen_string_literal: true
+
+require_relative "gem_version"
 
 module Rails
   # Returns the version of the currently loaded Rails as a string.
diff --git a/railties/lib/rails/welcome_controller.rb b/railties/lib/rails/welcome_controller.rb
index de9cd18b01..5b84b57679 100644
--- a/railties/lib/rails/welcome_controller.rb
+++ b/railties/lib/rails/welcome_controller.rb
@@ -1,4 +1,6 @@
-require 'rails/application_controller'
+# frozen_string_literal: true
+
+require "rails/application_controller"
 
 class Rails::WelcomeController < Rails::ApplicationController # :nodoc:
   layout false
diff --git a/railties/railties.gemspec b/railties/railties.gemspec
index fa417816eb..4c665cd546 100644
--- a/railties/railties.gemspec
+++ b/railties/railties.gemspec
@@ -1,34 +1,41 @@
-version = File.read(File.expand_path('../../RAILS_VERSION', __FILE__)).strip
+# frozen_string_literal: true
+
+version = File.read(File.expand_path("../RAILS_VERSION", __dir__)).strip
 
 Gem::Specification.new do |s|
   s.platform    = Gem::Platform::RUBY
-  s.name        = 'railties'
+  s.name        = "railties"
   s.version     = version
-  s.summary     = 'Tools for creating, working with, and running Rails applications.'
-  s.description = 'Rails internals: application bootup, plugins, generators, and rake tasks.'
+  s.summary     = "Tools for creating, working with, and running Rails applications."
+  s.description = "Rails internals: application bootup, plugins, generators, and rake tasks."
+
+  s.required_ruby_version = ">= 2.2.2"
 
-  s.required_ruby_version = '>= 2.2.2'
+  s.license = "MIT"
 
-  s.license = 'MIT'
+  s.author   = "David Heinemeier Hansson"
+  s.email    = "david@loudthinking.com"
+  s.homepage = "http://rubyonrails.org"
 
-  s.author   = 'David Heinemeier Hansson'
-  s.email    = 'david@loudthinking.com'
-  s.homepage = 'http://rubyonrails.org'
+  s.files        = Dir["CHANGELOG.md", "README.rdoc", "MIT-LICENSE", "RDOC_MAIN.rdoc", "exe/**/*", "lib/**/{*,.[a-z]*}"]
+  s.require_path = "lib"
 
-  s.files        = Dir['CHANGELOG.md', 'README.rdoc', 'MIT-LICENSE', 'RDOC_MAIN.rdoc', 'exe/**/*', 'lib/**/{*,.[a-z]*}']
-  s.require_path = 'lib'
+  s.bindir      = "exe"
+  s.executables = ["rails"]
 
-  s.bindir      = 'exe'
-  s.executables = ['rails']
+  s.rdoc_options << "--exclude" << "."
 
-  s.rdoc_options << '--exclude' << '.'
+  s.metadata = {
+    "source_code_uri" => "https://github.com/rails/rails/tree/v#{version}/railties",
+    "changelog_uri"   => "https://github.com/rails/rails/blob/v#{version}/railties/CHANGELOG.md"
+  }
 
-  s.add_dependency 'activesupport', version
-  s.add_dependency 'actionpack',    version
+  s.add_dependency "activesupport", version
+  s.add_dependency "actionpack",    version
 
-  s.add_dependency 'rake', '>= 0.8.7'
-  s.add_dependency 'thor', '>= 0.18.1', '< 2.0'
-  s.add_dependency 'method_source'
+  s.add_dependency "rake", ">= 0.8.7"
+  s.add_dependency "thor", ">= 0.18.1", "< 2.0"
+  s.add_dependency "method_source"
 
-  s.add_development_dependency 'actionview', version
+  s.add_development_dependency "actionview", version
 end
diff --git a/railties/test/abstract_unit.rb b/railties/test/abstract_unit.rb
index 2a5a731fe2..b42f37d6b9 100644
--- a/railties/test/abstract_unit.rb
+++ b/railties/test/abstract_unit.rb
@@ -1,31 +1,32 @@
+# frozen_string_literal: true
+
 ENV["RAILS_ENV"] ||= "test"
 
-require 'stringio'
-require 'active_support/testing/autorun'
-require 'active_support/testing/stream'
-require 'fileutils'
+require "stringio"
+require "active_support/testing/autorun"
+require "active_support/testing/stream"
+require "fileutils"
 
-require 'active_support'
-require 'action_controller'
-require 'action_view'
-require 'rails/all'
+require "active_support"
+require "action_controller"
+require "action_view"
+require "rails/all"
 
 module TestApp
   class Application < Rails::Application
-    config.root = File.dirname(__FILE__)
-    secrets.secret_key_base = 'b3c631c314c0bbca50c1b2843150fe33'
+    config.root = __dir__
   end
 end
 
-# Skips the current run on Rubinius using Minitest::Assertions#skip
-def rubinius_skip(message = '')
-  skip message if RUBY_ENGINE == 'rbx'
-end
-# Skips the current run on JRuby using Minitest::Assertions#skip
-def jruby_skip(message = '')
-  skip message if defined?(JRUBY_VERSION)
-end
-
 class ActiveSupport::TestCase
   include ActiveSupport::Testing::Stream
+
+  # Skips the current run on Rubinius using Minitest::Assertions#skip
+  private def rubinius_skip(message = "")
+    skip message if RUBY_ENGINE == "rbx"
+  end
+  # Skips the current run on JRuby using Minitest::Assertions#skip
+  private def jruby_skip(message = "")
+    skip message if defined?(JRUBY_VERSION)
+  end
 end
diff --git a/railties/test/app_loader_test.rb b/railties/test/app_loader_test.rb
index 5946c8fd4c..bb556f1968 100644
--- a/railties/test/app_loader_test.rb
+++ b/railties/test/app_loader_test.rb
@@ -1,6 +1,8 @@
-require 'tmpdir'
-require 'abstract_unit'
-require 'rails/app_loader'
+# frozen_string_literal: true
+
+require "tmpdir"
+require "abstract_unit"
+require "rails/app_loader"
 
 class AppLoaderTest < ActiveSupport::TestCase
   def loader
@@ -17,7 +19,7 @@ class AppLoaderTest < ActiveSupport::TestCase
     end
   end
 
-  def write(filename, contents=nil)
+  def write(filename, contents = nil)
     FileUtils.mkdir_p(File.dirname(filename))
     File.write(filename, contents)
   end
@@ -27,12 +29,12 @@ class AppLoaderTest < ActiveSupport::TestCase
   end
 
   setup do
-    @tmp = Dir.mktmpdir('railties-rails-loader-test-suite')
+    @tmp = Dir.mktmpdir("railties-rails-loader-test-suite")
     @cwd = Dir.pwd
     Dir.chdir(@tmp)
   end
 
-  ['bin', 'script'].each do |script_dir|
+  ["bin", "script"].each do |script_dir|
     exe = "#{script_dir}/rails"
 
     test "is not in a Rails application if #{exe} is not found in the current or parent directories" do
@@ -47,7 +49,7 @@ class AppLoaderTest < ActiveSupport::TestCase
       assert !loader.exec_app
     end
 
-    ['APP_PATH', 'ENGINE_PATH'].each do |keyword|
+    ["APP_PATH", "ENGINE_PATH"].each do |keyword|
       test "is in a Rails application if #{exe} exists and contains #{keyword}" do
         write exe, keyword
 
@@ -66,7 +68,7 @@ class AppLoaderTest < ActiveSupport::TestCase
         write "foo/bar/#{exe}"
         write "foo/#{exe}", keyword
 
-        Dir.chdir('foo/bar')
+        Dir.chdir("foo/bar")
 
         loader.exec_app
 
diff --git a/railties/test/application/asset_debugging_test.rb b/railties/test/application/asset_debugging_test.rb
index bcb6aff0d7..e56c7b958e 100644
--- a/railties/test/application/asset_debugging_test.rb
+++ b/railties/test/application/asset_debugging_test.rb
@@ -1,5 +1,7 @@
-require 'isolation/abstract_unit'
-require 'rack/test'
+# frozen_string_literal: true
+
+require "isolation/abstract_unit"
+require "rack/test"
 
 module ApplicationTests
   class AssetDebuggingTest < ActiveSupport::TestCase
@@ -7,10 +9,7 @@ module ApplicationTests
     include Rack::Test::Methods
 
     def setup
-      # FIXME: shush Sass warning spam, not relevant to testing Railties
-      Kernel.silence_warnings do
-        build_app(initializers: true)
-      end
+      build_app(initializers: true)
 
       app_file "app/assets/javascripts/application.js", "//= require_tree ."
       app_file "app/assets/javascripts/xmlhr.js", "function f1() { alert(); }"
@@ -28,24 +27,16 @@ module ApplicationTests
       RUBY
 
       ENV["RAILS_ENV"] = "production"
-
-      boot_rails
     end
 
     def teardown
       teardown_app
     end
 
-    # FIXME: shush Sass warning spam, not relevant to testing Railties
-    def get(*)
-      Kernel.silence_warnings { super }
-    end
-
     test "assets are concatenated when debug is off and compile is off either if debug_assets param is provided" do
       # config.assets.debug and config.assets.compile are false for production environment
       ENV["RAILS_ENV"] = "production"
-      output = Dir.chdir(app_path){ `bin/rails assets:precompile --trace 2>&1` }
-      assert $?.success?, output
+      rails "assets:precompile", "--trace"
 
       # Load app env
       app "production"
@@ -53,7 +44,7 @@ module ApplicationTests
       class ::PostsController < ActionController::Base ; end
 
       # the debug_assets params isn't used if compile is off
-      get '/posts?debug_assets=true'
+      get "/posts?debug_assets=true"
       assert_match(/<script src="\/assets\/application-([0-z]+)\.js"><\/script>/, last_response.body)
       assert_no_match(/<script src="\/assets\/xmlhr-([0-z]+)\.js"><\/script>/, last_response.body)
     end
@@ -66,9 +57,106 @@ module ApplicationTests
 
       class ::PostsController < ActionController::Base ; end
 
-      get '/posts?debug_assets=true'
+      get "/posts?debug_assets=true"
       assert_match(/<script src="\/assets\/application(\.self)?-([0-z]+)\.js\?body=1"><\/script>/, last_response.body)
       assert_match(/<script src="\/assets\/xmlhr(\.self)?-([0-z]+)\.js\?body=1"><\/script>/, last_response.body)
     end
+
+    test "public path and tag methods are not over-written by the asset pipeline" do
+      contents = "doesnotexist"
+      cases = {
+        asset_path:             %r{/#{contents}},
+        image_path:             %r{/images/#{contents}},
+        video_path:             %r{/videos/#{contents}},
+        audio_path:             %r{/audios/#{contents}},
+        font_path:              %r{/fonts/#{contents}},
+        javascript_path:        %r{/javascripts/#{contents}},
+        stylesheet_path:        %r{/stylesheets/#{contents}},
+        image_tag:              %r{<img src="/images/#{contents}"},
+        favicon_link_tag:       %r{<link rel="shortcut icon" type="image/x-icon" href="/images/#{contents}" />},
+        stylesheet_link_tag:    %r{<link rel="stylesheet" media="screen" href="/stylesheets/#{contents}.css" />},
+        javascript_include_tag: %r{<script src="/javascripts/#{contents}.js">},
+        audio_tag:              %r{<audio src="/audios/#{contents}"></audio>},
+        video_tag:              %r{<video src="/videos/#{contents}"></video>}
+      }
+
+      cases.each do |(view_method, tag_match)|
+        app_file "app/views/posts/index.html.erb", "<%= #{view_method} '#{contents}', skip_pipeline: true %>"
+
+        app "development"
+
+        class ::PostsController < ActionController::Base ; end
+
+        get "/posts?debug_assets=true"
+
+        body = last_response.body
+        assert_match(tag_match, body, "Expected `#{view_method}` to produce a match to #{tag_match}, but did not: #{body}")
+      end
+    end
+
+    test "public url methods are not over-written by the asset pipeline" do
+      contents = "doesnotexist"
+      cases = {
+        asset_url:       %r{http://example.org/#{contents}},
+        image_url:       %r{http://example.org/images/#{contents}},
+        video_url:       %r{http://example.org/videos/#{contents}},
+        audio_url:       %r{http://example.org/audios/#{contents}},
+        font_url:        %r{http://example.org/fonts/#{contents}},
+        javascript_url:  %r{http://example.org/javascripts/#{contents}},
+        stylesheet_url:  %r{http://example.org/stylesheets/#{contents}},
+      }
+
+      cases.each do |(view_method, tag_match)|
+        app_file "app/views/posts/index.html.erb", "<%= #{view_method} '#{contents}', skip_pipeline: true %>"
+
+        app "development"
+
+        class ::PostsController < ActionController::Base ; end
+
+        get "/posts?debug_assets=true"
+
+        body = last_response.body
+        assert_match(tag_match, body, "Expected `#{view_method}` to produce a match to #{tag_match}, but did not: #{body}")
+      end
+    end
+
+    test "{ skip_pipeline: true } does not use the asset pipeline" do
+      cases = {
+        /\/assets\/application-.*.\.js/ => {},
+        /application.js/                => { skip_pipeline: true },
+      }
+      cases.each do |(tag_match, options_hash)|
+        app_file "app/views/posts/index.html.erb", "<%= asset_path('application.js', #{options_hash}) %>"
+
+        app "development"
+
+        class ::PostsController < ActionController::Base ; end
+
+        get "/posts?debug_assets=true"
+
+        body = last_response.body.strip
+        assert_match(tag_match, body, "Expected `asset_path` with `#{options_hash}` to produce a match to #{tag_match}, but did not: #{body}")
+      end
+    end
+
+    test "public_compute_asset_path does not use the asset pipeline" do
+      cases = {
+        compute_asset_path:        /\/assets\/application-.*.\.js/,
+        public_compute_asset_path: /application.js/,
+      }
+
+      cases.each do |(view_method, tag_match)|
+        app_file "app/views/posts/index.html.erb", "<%= #{ view_method } 'application.js' %>"
+
+        app "development"
+
+        class ::PostsController < ActionController::Base ; end
+
+        get "/posts?debug_assets=true"
+
+        body = last_response.body.strip
+        assert_match(tag_match, body, "Expected `#{view_method}` to produce a match to #{ tag_match }, but did not: #{ body }")
+      end
+    end
   end
 end
diff --git a/railties/test/application/assets_test.rb b/railties/test/application/assets_test.rb
index 9e8531b482..0d3262d6f6 100644
--- a/railties/test/application/assets_test.rb
+++ b/railties/test/application/assets_test.rb
@@ -1,6 +1,8 @@
-require 'isolation/abstract_unit'
-require 'rack/test'
-require 'active_support/json'
+# frozen_string_literal: true
+
+require "isolation/abstract_unit"
+require "rack/test"
+require "active_support/json"
 
 module ApplicationTests
   class AssetsTest < ActiveSupport::TestCase
@@ -9,7 +11,6 @@ module ApplicationTests
 
     def setup
       build_app(initializers: true)
-      boot_rails
     end
 
     def teardown
@@ -36,7 +37,7 @@ module ApplicationTests
 
     def clean_assets!
       quietly do
-        assert Dir.chdir(app_path) { system('bin/rails assets:clobber') }
+        assert Dir.chdir(app_path) { system("bin/rails assets:clobber") }
       end
     end
 
@@ -53,7 +54,7 @@ module ApplicationTests
       app_file "app/assets/images/rails.png", "notactuallyapng"
       app_file "app/assets/javascripts/demo.js.erb", "a = <%= image_path('rails.png').inspect %>;"
 
-      app_file 'config/routes.rb', <<-RUBY
+      app_file "config/routes.rb", <<-RUBY
         Rails.application.routes.draw do
           get '*path', to: lambda { |env| [200, { "Content-Type" => "text/html" }, ["Not an asset"]] }
         end
@@ -61,10 +62,7 @@ module ApplicationTests
 
       add_to_env_config "development", "config.assets.digest = false"
 
-      # FIXME: shush Sass warning spam, not relevant to testing Railties
-      Kernel.silence_warnings do
-        require "#{app_path}/config/environment"
-      end
+      require "#{app_path}/config/environment"
 
       get "/assets/demo.js"
       assert_equal 'a = "/assets/rails.png";', last_response.body.strip
@@ -111,8 +109,8 @@ module ApplicationTests
       eoruby
 
       precompile! \
-        RAILS_ENV: 'production',
-        DATABASE_URL: 'postgresql://baduser:badpass@127.0.0.1/dbname'
+        RAILS_ENV: "production",
+        DATABASE_URL: "postgresql://baduser:badpass@127.0.0.1/dbname"
 
       files = Dir["#{app_path}/public/assets/application-*.js"]
       files << Dir["#{app_path}/public/assets/foo/application-*.js"].first
@@ -177,19 +175,19 @@ module ApplicationTests
       assert_file_exists("#{app_path}/public/assets/something/index-*.js")
     end
 
-    test 'precompile use assets defined in app env config' do
-      add_to_env_config 'production', 'config.assets.precompile = [ "something.js" ]'
-      app_file 'app/assets/javascripts/something.js.erb', 'alert();'
+    test "precompile use assets defined in app env config" do
+      add_to_env_config "production", 'config.assets.precompile = [ "something.js" ]'
+      app_file "app/assets/javascripts/something.js.erb", "alert();"
 
-      precompile! RAILS_ENV: 'production'
+      precompile! RAILS_ENV: "production"
 
       assert_file_exists("#{app_path}/public/assets/something-*.js")
     end
 
-    test 'sprockets cache is not shared between environments' do
+    test "sprockets cache is not shared between environments" do
       app_file "app/assets/images/rails.png", "notactuallyapng"
-      app_file "app/assets/stylesheets/application.css.erb", "<%= asset_path('rails.png') %>"
-      add_to_env_config 'production', 'config.assets.prefix = "production_assets"'
+      app_file "app/assets/stylesheets/application.css.erb", "body { background: '<%= asset_path('rails.png') %>'; }"
+      add_to_env_config "production", 'config.assets.prefix = "production_assets"'
 
       precompile!
 
@@ -198,7 +196,7 @@ module ApplicationTests
       file = Dir["#{app_path}/public/assets/application-*.css"].first
       assert_match(/assets\/rails-([0-z]+)\.png/, File.read(file))
 
-      precompile! RAILS_ENV: 'production'
+      precompile! RAILS_ENV: "production"
 
       assert_file_exists("#{app_path}/public/production_assets/application-*.css")
 
@@ -206,17 +204,17 @@ module ApplicationTests
       assert_match(/production_assets\/rails-([0-z]+)\.png/, File.read(file))
     end
 
-    test 'precompile use assets defined in app config and reassigned in app env config' do
+    test "precompile use assets defined in app config and reassigned in app env config" do
       add_to_config 'config.assets.precompile = [ "something_manifest.js" ]'
-      add_to_env_config 'production', 'config.assets.precompile += [ "another_manifest.js" ]'
+      add_to_env_config "production", 'config.assets.precompile += [ "another_manifest.js" ]'
 
-      app_file 'app/assets/config/something_manifest.js', '//= link something.js'
-      app_file 'app/assets/config/another_manifest.js', '//= link another.js'
+      app_file "app/assets/config/something_manifest.js", "//= link something.js"
+      app_file "app/assets/config/another_manifest.js", "//= link another.js"
 
-      app_file 'app/assets/javascripts/something.js.erb', 'alert();'
-      app_file 'app/assets/javascripts/another.js.erb', 'alert();'
+      app_file "app/assets/javascripts/something.js.erb", "alert();"
+      app_file "app/assets/javascripts/another.js.erb", "alert();"
 
-      precompile! RAILS_ENV: 'production'
+      precompile! RAILS_ENV: "production"
 
       assert_file_exists("#{app_path}/public/assets/something_manifest-*.js")
       assert_file_exists("#{app_path}/public/assets/something-*.js")
@@ -262,7 +260,7 @@ module ApplicationTests
       app_file "app/assets/javascripts/application.js", "alert();"
       add_to_env_config "production", "config.public_file_server.enabled = true"
 
-      precompile! RAILS_ENV: 'production'
+      precompile! RAILS_ENV: "production"
 
       manifest = Dir["#{app_path}/public/assets/.sprockets-manifest-*.json"].first
       assets = ActiveSupport::JSON.decode(File.read(manifest))
@@ -293,7 +291,7 @@ module ApplicationTests
 
       app_file "app/assets/stylesheets/application.css.erb", "p { background-image: url(<%= asset_path('rails.png') %>) }"
 
-      precompile! RAILS_ENV: 'production'
+      precompile! RAILS_ENV: "production"
 
       manifest = Dir["#{app_path}/public/assets/.sprockets-manifest-*.json"].first
       assets = ActiveSupport::JSON.decode(File.read(manifest))
@@ -311,7 +309,7 @@ module ApplicationTests
       app_file "app/assets/images/rails.png", "notactuallyapng"
       app_file "app/assets/stylesheets/application.css.erb", "p { background-image: url(<%= asset_path('rails.png') %>) }"
 
-      precompile! RAILS_ENV: 'production'
+      precompile! RAILS_ENV: "production"
 
       file = Dir["#{app_path}/public/assets/application-*.css"].first
       assert_match(/\/assets\/rails-([0-z]+)\.png/, File.read(file))
@@ -376,16 +374,16 @@ module ApplicationTests
       class ::OmgController < ActionController::Base
         def index
           flash[:cool_story] = true
-          render text: "ok"
+          render plain: "ok"
         end
       end
 
       get "/omg"
-      assert_equal 'ok', last_response.body
+      assert_equal "ok", last_response.body
 
       get "/assets/demo.js"
       assert_match "alert()", last_response.body
-      assert_equal nil, last_response.headers["Set-Cookie"]
+      assert_nil last_response.headers["Set-Cookie"]
     end
 
     test "files in any assets/ directories are not added to Sprockets" do
@@ -409,7 +407,7 @@ module ApplicationTests
       app_with_assets_in_view
 
       # config.assets.debug and config.assets.compile are false for production environment
-      precompile! RAILS_ENV: 'production'
+      precompile! RAILS_ENV: "production"
 
       # Load app env
       app "production"
@@ -417,7 +415,7 @@ module ApplicationTests
       class ::PostsController < ActionController::Base ; end
 
       # the debug_assets params isn't used if compile is off
-      get '/posts?debug_assets=true'
+      get "/posts?debug_assets=true"
       assert_match(/<script src="\/assets\/application-([0-z]+)\.js"><\/script>/, last_response.body)
       assert_no_match(/<script src="\/assets\/xmlhr-([0-z]+)\.js"><\/script>/, last_response.body)
     end
@@ -476,9 +474,9 @@ module ApplicationTests
 
       class ::PostsController < ActionController::Base; end
 
-      get '/posts', {}, {'HTTPS'=>'off'}
+      get "/posts", {}, { "HTTPS" => "off" }
       assert_match('src="http://example.com/assets/application.self.js', last_response.body)
-      get '/posts', {}, {'HTTPS'=>'on'}
+      get "/posts", {}, { "HTTPS" => "on" }
       assert_match('src="https://example.com/assets/application.self.js', last_response.body)
     end
 
@@ -508,16 +506,16 @@ module ApplicationTests
 
     private
 
-    def app_with_assets_in_view
-      app_file "app/assets/javascripts/application.js", "//= require_tree ."
-      app_file "app/assets/javascripts/xmlhr.js", "function f1() { alert(); }"
-      app_file "app/views/posts/index.html.erb", "<%= javascript_include_tag 'application' %>"
+      def app_with_assets_in_view
+        app_file "app/assets/javascripts/application.js", "//= require_tree ."
+        app_file "app/assets/javascripts/xmlhr.js", "function f1() { alert(); }"
+        app_file "app/views/posts/index.html.erb", "<%= javascript_include_tag 'application' %>"
 
-      app_file "config/routes.rb", <<-RUBY
+        app_file "config/routes.rb", <<-RUBY
         Rails.application.routes.draw do
           get '/posts', :to => "posts#index"
         end
       RUBY
-    end
+      end
   end
 end
diff --git a/railties/test/application/bin_setup_test.rb b/railties/test/application/bin_setup_test.rb
index ba700df1d6..54934dbe24 100644
--- a/railties/test/application/bin_setup_test.rb
+++ b/railties/test/application/bin_setup_test.rb
@@ -1,4 +1,6 @@
-require 'isolation/abstract_unit'
+# frozen_string_literal: true
+
+require "isolation/abstract_unit"
 
 module ApplicationTests
   class BinSetupTest < ActiveSupport::TestCase
@@ -14,16 +16,16 @@ module ApplicationTests
 
     def test_bin_setup
       Dir.chdir(app_path) do
-        app_file 'db/schema.rb', <<-RUBY
+        app_file "db/schema.rb", <<-RUBY
           ActiveRecord::Schema.define(version: 20140423102712) do
             create_table(:articles) {}
           end
         RUBY
 
-        list_tables = lambda { `bin/rails runner 'p ActiveRecord::Base.connection.tables'`.strip }
+        list_tables = lambda { rails("runner", "p ActiveRecord::Base.connection.tables").strip }
         File.write("log/test.log", "zomg!")
 
-        assert_equal '[]', list_tables.call
+        assert_equal "[]", list_tables.call
         assert_equal 5, File.size("log/test.log")
         assert_not File.exist?("tmp/restart.txt")
         `bin/setup 2>&1`
@@ -35,9 +37,13 @@ module ApplicationTests
 
     def test_bin_setup_output
       Dir.chdir(app_path) do
-        app_file 'db/schema.rb', ""
+        app_file "db/schema.rb", ""
 
         output = `bin/setup 2>&1`
+
+        # Ignore line that's only output by Bundler < 1.14
+        output.sub!(/^Resolving dependencies\.\.\.\n/, "")
+
         assert_equal(<<-OUTPUT, output)
 == Installing dependencies ==
 The Gemfile's dependencies are satisfied
diff --git a/railties/test/application/configuration/custom_test.rb b/railties/test/application/configuration/custom_test.rb
index 28b3b2f2d6..05b17b4a7a 100644
--- a/railties/test/application/configuration/custom_test.rb
+++ b/railties/test/application/configuration/custom_test.rb
@@ -1,20 +1,20 @@
-require 'isolation/abstract_unit'
+# frozen_string_literal: true
+
+require "isolation/abstract_unit"
 
 module ApplicationTests
   module ConfigurationTests
     class CustomTest < ActiveSupport::TestCase
       def setup
         build_app
-        boot_rails
         FileUtils.rm_rf("#{app_path}/config/environments")
       end
 
       def teardown
         teardown_app
-        FileUtils.rm_rf(new_app) if File.directory?(new_app)
       end
 
-      test 'access custom configuration point' do
+      test "access custom configuration point" do
         add_to_config <<-RUBY
           config.x.payment_processing.schedule = :daily
           config.x.payment_processing.retries  = 3
@@ -29,23 +29,16 @@ module ApplicationTests
         assert_equal 3, x.payment_processing.retries
         assert_equal true, x.super_debugger
         assert_equal false, x.hyper_debugger
-        assert_equal nil, x.nil_debugger
+        assert_nil x.nil_debugger
         assert_nil x.i_do_not_exist.zomg
+
+        # test that custom configuration responds to all messages
+        assert_equal true, x.respond_to?(:i_do_not_exist)
+        assert_kind_of Method, x.method(:i_do_not_exist)
+        assert_kind_of ActiveSupport::OrderedOptions, x.i_do_not_exist
       end
 
       private
-        def new_app
-          File.expand_path("#{app_path}/../new_app")
-        end
-
-        def copy_app
-          FileUtils.cp_r(app_path, new_app)
-        end
-
-        def app
-          @app ||= Rails.application
-        end
-
         def require_environment
           require "#{app_path}/config/environment"
         end
diff --git a/railties/test/application/configuration_test.rb b/railties/test/application/configuration_test.rb
index 7ec25aeca1..907eb4fa58 100644
--- a/railties/test/application/configuration_test.rb
+++ b/railties/test/application/configuration_test.rb
@@ -1,6 +1,8 @@
+# frozen_string_literal: true
+
 require "isolation/abstract_unit"
-require 'rack/test'
-require 'env_helpers'
+require "rack/test"
+require "env_helpers"
 
 class ::MyMailInterceptor
   def self.delivering_email(email); email; end
@@ -34,25 +36,21 @@ module ApplicationTests
       FileUtils.cp_r(app_path, new_app)
     end
 
-    def app(env = 'development')
+    def app(env = "development")
       @app ||= begin
-        ENV['RAILS_ENV'] = env
+        ENV["RAILS_ENV"] = env
 
-        # FIXME: shush Sass warning spam, not relevant to testing Railties
-        Kernel.silence_warnings do
-          require "#{app_path}/config/environment"
-        end
+        require "#{app_path}/config/environment"
 
         Rails.application
       ensure
-        ENV.delete 'RAILS_ENV'
+        ENV.delete "RAILS_ENV"
       end
     end
 
     def setup
       build_app
-      boot_rails
-      supress_default_config
+      suppress_default_config
     end
 
     def teardown
@@ -60,7 +58,7 @@ module ApplicationTests
       FileUtils.rm_rf(new_app) if File.directory?(new_app)
     end
 
-    def supress_default_config
+    def suppress_default_config
       FileUtils.mv("#{app_path}/config/environments", "#{app_path}/config/__environments__")
     end
 
@@ -75,7 +73,19 @@ module ApplicationTests
       switch_env "RAILS_ENV", nil do
         Rails.env = "development"
         assert_equal "development", Rails.env
-        assert_nil ENV['RAILS_ENV']
+        assert_nil ENV["RAILS_ENV"]
+      end
+    end
+
+    test "Rails.env falls back to development if RAILS_ENV is blank and RACK_ENV is nil" do
+      with_rails_env("") do
+        assert_equal "development", Rails.env
+      end
+    end
+
+    test "Rails.env falls back to development if RACK_ENV is blank and RAILS_ENV is nil" do
+      with_rack_env("") do
+        assert_equal "development", Rails.env
       end
     end
 
@@ -83,7 +93,7 @@ module ApplicationTests
       restore_default_config
 
       with_rails_env "development" do
-        app 'development'
+        app "development"
         assert Rails.application.config.log_tags.blank?
       end
     end
@@ -92,13 +102,13 @@ module ApplicationTests
       restore_default_config
 
       with_rails_env "production" do
-        app 'production'
+        app "production"
         assert_equal [:request_id], Rails.application.config.log_tags
       end
     end
 
     test "lib dir is on LOAD_PATH during config" do
-      app_file 'lib/my_logger.rb', <<-RUBY
+      app_file "lib/my_logger.rb", <<-RUBY
         require "logger"
         class MyLogger < ::Logger
         end
@@ -108,9 +118,9 @@ module ApplicationTests
         config.logger = MyLogger.new STDOUT
       RUBY
 
-      app 'development'
+      app "development"
 
-      assert_equal 'MyLogger', Rails.application.config.logger.class.name
+      assert_equal "MyLogger", Rails.application.config.logger.class.name
     end
 
     test "a renders exception on pending migration" do
@@ -120,7 +130,7 @@ module ApplicationTests
         config.action_dispatch.show_exceptions  = true
       RUBY
 
-      app_file 'db/migrate/20140708012246_create_user.rb', <<-RUBY
+      app_file "db/migrate/20140708012246_create_user.rb", <<-RUBY
         class CreateUser < ActiveRecord::Migration::Current
           def change
             create_table :users
@@ -128,7 +138,7 @@ module ApplicationTests
         end
       RUBY
 
-      app 'development'
+      app "development"
 
       ActiveRecord::Migrator.migrations_paths = ["#{app_path}/db/migrate"]
 
@@ -157,31 +167,29 @@ module ApplicationTests
     end
 
     test "Rails.application is nil until app is initialized" do
-      require 'rails'
+      require "rails"
       assert_nil Rails.application
-      app 'development'
+      app "development"
       assert_equal AppTemplate::Application.instance, Rails.application
     end
 
     test "Rails.application responds to all instance methods" do
-      app 'development'
-      assert_respond_to Rails.application, :routes_reloader
+      app "development"
       assert_equal Rails.application.routes_reloader, AppTemplate::Application.routes_reloader
     end
 
     test "Rails::Application responds to paths" do
-      app 'development'
-      assert_respond_to AppTemplate::Application, :paths
+      app "development"
       assert_equal ["#{app_path}/app/views"], AppTemplate::Application.paths["app/views"].expanded
     end
 
     test "the application root is set correctly" do
-      app 'development'
+      app "development"
       assert_equal Pathname.new(app_path), Rails.application.root
     end
 
     test "the application root can be seen from the application singleton" do
-      app 'development'
+      app "development"
       assert_equal Pathname.new(app_path), AppTemplate::Application.root
     end
 
@@ -193,7 +201,7 @@ module ApplicationTests
 
       use_frameworks []
 
-      app 'development'
+      app "development"
 
       assert_equal Pathname.new(new_app), Rails.application.root
     end
@@ -204,7 +212,7 @@ module ApplicationTests
       use_frameworks []
 
       Dir.chdir("#{app_path}") do
-        app 'development'
+        app "development"
         assert_equal Pathname.new("#{app_path}"), Rails.application.root
       end
     end
@@ -214,7 +222,7 @@ module ApplicationTests
         config.root = "#{app_path}"
       RUBY
 
-      app 'development'
+      app "development"
 
       assert_instance_of Pathname, Rails.root
     end
@@ -224,28 +232,89 @@ module ApplicationTests
         config.paths["public"] = "somewhere"
       RUBY
 
-      app 'development'
+      app "development"
 
       assert_instance_of Pathname, Rails.public_path
     end
 
+    test "does not eager load controller actions in development" do
+      app_file "app/controllers/posts_controller.rb", <<-RUBY
+        class PostsController < ActionController::Base
+          def index;end
+          def show;end
+        end
+      RUBY
+
+      app "development"
+
+      assert_nil PostsController.instance_variable_get(:@action_methods)
+    end
+
+    test "eager loads controller actions in production" do
+      app_file "app/controllers/posts_controller.rb", <<-RUBY
+        class PostsController < ActionController::Base
+          def index;end
+          def show;end
+        end
+      RUBY
+
+      add_to_config <<-RUBY
+        config.eager_load = true
+        config.cache_classes = true
+      RUBY
+
+      app "production"
+
+      assert_equal %w(index show).to_set, PostsController.instance_variable_get(:@action_methods)
+    end
+
+    test "does not eager load mailer actions in development" do
+      app_file "app/mailers/posts_mailer.rb", <<-RUBY
+        class PostsMailer < ActionMailer::Base
+          def noop_email;end
+        end
+      RUBY
+
+      app "development"
+
+      assert_nil PostsMailer.instance_variable_get(:@action_methods)
+    end
+
+    test "eager loads mailer actions in production" do
+      app_file "app/mailers/posts_mailer.rb", <<-RUBY
+        class PostsMailer < ActionMailer::Base
+          def noop_email;end
+        end
+      RUBY
+
+      add_to_config <<-RUBY
+        config.eager_load = true
+        config.cache_classes = true
+      RUBY
+
+      app "production"
+
+      assert_equal %w(noop_email).to_set, PostsMailer.instance_variable_get(:@action_methods)
+    end
+
     test "initialize an eager loaded, cache classes app" do
       add_to_config <<-RUBY
         config.eager_load = true
         config.cache_classes = true
       RUBY
 
-      app 'development'
+      app "development"
 
       assert_equal :require, ActiveSupport::Dependencies.mechanism
     end
 
     test "application is always added to eager_load namespaces" do
-      app 'development'
+      app "development"
       assert_includes Rails.application.config.eager_load_namespaces, AppTemplate::Application
     end
 
     test "the application can be eager loaded even when there are no frameworks" do
+      FileUtils.rm_rf("#{app_path}/app/jobs/application_job.rb")
       FileUtils.rm_rf("#{app_path}/app/models/application_record.rb")
       FileUtils.rm_rf("#{app_path}/app/mailers/application_mailer.rb")
       FileUtils.rm_rf("#{app_path}/config/environments")
@@ -257,7 +326,7 @@ module ApplicationTests
       use_frameworks []
 
       assert_nothing_raised do
-        app 'development'
+        app "development"
       end
     end
 
@@ -269,18 +338,18 @@ module ApplicationTests
       RUBY
 
       assert_nothing_raised do
-        app 'development'
+        app "development"
       end
     end
 
     test "filter_parameters should be able to set via config.filter_parameters in an initializer" do
-      app_file 'config/initializers/filter_parameters_logging.rb', <<-RUBY
+      app_file "config/initializers/filter_parameters_logging.rb", <<-RUBY
         Rails.application.config.filter_parameters += [ :password, :foo, 'bar' ]
       RUBY
 
-      app 'development'
+      app "development"
 
-      assert_equal [:password, :foo, 'bar'], Rails.application.env_config['action_dispatch.parameter_filter']
+      assert_equal [:password, :foo, "bar"], Rails.application.env_config["action_dispatch.parameter_filter"]
     end
 
     test "config.to_prepare is forwarded to ActionDispatch" do
@@ -294,7 +363,7 @@ module ApplicationTests
 
       assert !$prepared
 
-      app 'development'
+      app "development"
 
       get "/"
       assert $prepared
@@ -306,7 +375,7 @@ module ApplicationTests
     end
 
     test "skipping config.encoding still results in 'utf-8' as the default" do
-      app 'development'
+      app "development"
       assert_utf8
     end
 
@@ -315,7 +384,7 @@ module ApplicationTests
         config.encoding = "utf-8"
       RUBY
 
-      app 'development'
+      app "development"
       assert_utf8
     end
 
@@ -324,7 +393,7 @@ module ApplicationTests
         config.paths["public"] = "somewhere"
       RUBY
 
-      app 'development'
+      app "development"
       assert_equal Pathname.new(app_path).join("somewhere"), Rails.public_path
     end
 
@@ -332,7 +401,7 @@ module ApplicationTests
       restore_default_config
 
       with_rails_env "production" do
-        app 'production'
+        app "production"
         assert_not app.config.public_file_server.enabled
       end
     end
@@ -342,7 +411,7 @@ module ApplicationTests
 
       with_rails_env "production" do
         switch_env "RAILS_SERVE_STATIC_FILES", "1" do
-          app 'production'
+          app "production"
           assert app.config.public_file_server.enabled
         end
       end
@@ -353,7 +422,7 @@ module ApplicationTests
 
       with_rails_env "production" do
         switch_env "RAILS_LOG_TO_STDOUT", "1" do
-          app 'production'
+          app "production"
           assert ActiveSupport::Logger.logger_outputs_to?(app.config.logger, STDOUT)
         end
       end
@@ -364,139 +433,133 @@ module ApplicationTests
 
       with_rails_env "production" do
         switch_env "RAILS_SERVE_STATIC_FILES", " " do
-          app 'production'
+          app "production"
           assert_not app.config.public_file_server.enabled
         end
       end
     end
 
-    test "config.serve_static_files is deprecated" do
-      make_basic_app do |application|
-        assert_deprecated do
-          application.config.serve_static_files = true
-        end
-
-        assert application.config.public_file_server.enabled
-      end
-    end
-
-    test "config.static_cache_control is deprecated" do
-      make_basic_app do |application|
-        assert_deprecated do
-          application.config.static_cache_control = "public, max-age=60"
-        end
-
-        assert_equal application.config.static_cache_control, "public, max-age=60"
-      end
-    end
-
     test "Use key_generator when secret_key_base is set" do
       make_basic_app do |application|
-        application.secrets.secret_key_base = 'b3c631c314c0bbca50c1b2843150fe33'
+        application.secrets.secret_key_base = "b3c631c314c0bbca50c1b2843150fe33"
         application.config.session_store :disabled
       end
 
       class ::OmgController < ActionController::Base
         def index
           cookies.signed[:some_key] = "some_value"
-          render text: cookies[:some_key]
+          render plain: cookies[:some_key]
         end
       end
 
       get "/"
 
-      secret = app.key_generator.generate_key('signed cookie')
+      secret = app.key_generator.generate_key("signed cookie")
       verifier = ActiveSupport::MessageVerifier.new(secret)
-      assert_equal 'some_value', verifier.verify(last_response.body)
+      assert_equal "some_value", verifier.verify(last_response.body)
     end
 
     test "application verifier can be used in the entire application" do
       make_basic_app do |application|
-        application.secrets.secret_key_base = 'b3c631c314c0bbca50c1b2843150fe33'
+        application.secrets.secret_key_base = "b3c631c314c0bbca50c1b2843150fe33"
         application.config.session_store :disabled
       end
 
       message = app.message_verifier(:sensitive_value).generate("some_value")
 
-      assert_equal 'some_value', Rails.application.message_verifier(:sensitive_value).verify(message)
+      assert_equal "some_value", Rails.application.message_verifier(:sensitive_value).verify(message)
 
-      secret = app.key_generator.generate_key('sensitive_value')
+      secret = app.key_generator.generate_key("sensitive_value")
       verifier = ActiveSupport::MessageVerifier.new(secret)
-      assert_equal 'some_value', verifier.verify(message)
+      assert_equal "some_value", verifier.verify(message)
     end
 
     test "application message verifier can be used when the key_generator is ActiveSupport::LegacyKeyGenerator" do
-      app_file 'config/initializers/secret_token.rb', <<-RUBY
+      app_file "config/initializers/secret_token.rb", <<-RUBY
+        Rails.application.credentials.secret_key_base = nil
         Rails.application.config.secret_token = "b3c631c314c0bbca50c1b2843150fe33"
       RUBY
-      app_file 'config/secrets.yml', <<-YAML
-        development:
-          secret_key_base:
-      YAML
 
-      app 'development'
+      app "production"
 
-      assert_equal app.env_config['action_dispatch.key_generator'], Rails.application.key_generator
-      assert_equal app.env_config['action_dispatch.key_generator'].class, ActiveSupport::LegacyKeyGenerator
+      assert_kind_of ActiveSupport::LegacyKeyGenerator, Rails.application.key_generator
       message = app.message_verifier(:sensitive_value).generate("some_value")
-      assert_equal 'some_value', Rails.application.message_verifier(:sensitive_value).verify(message)
+      assert_equal "some_value", Rails.application.message_verifier(:sensitive_value).verify(message)
     end
 
-    test "warns when secrets.secret_key_base is blank and config.secret_token is set" do
-      app_file 'config/initializers/secret_token.rb', <<-RUBY
+    test "config.secret_token is deprecated" do
+      app_file "config/initializers/secret_token.rb", <<-RUBY
         Rails.application.config.secret_token = "b3c631c314c0bbca50c1b2843150fe33"
       RUBY
-      app_file 'config/secrets.yml', <<-YAML
-        development:
-          secret_key_base:
-      YAML
 
-      app 'development'
+      app "production"
 
-      assert_deprecated(/You didn't set `secret_key_base`./) do
-        app.env_config
+      assert_deprecated(/secret_token/) do
+        app.secrets
       end
     end
 
-    test "raise when secrets.secret_key_base is not a type of string" do
-      app_file 'config/secrets.yml', <<-YAML
-        development:
-          secret_key_base: 123
+    test "secrets.secret_token is deprecated" do
+      app_file "config/secrets.yml", <<-YAML
+        production:
+          secret_token: "b3c631c314c0bbca50c1b2843150fe33"
       YAML
 
-      app 'development'
+      app "production"
+
+      assert_deprecated(/secret_token/) do
+        app.secrets
+      end
+    end
+
+
+    test "raises when secret_key_base is blank" do
+      app_file "config/initializers/secret_token.rb", <<-RUBY
+        Rails.application.credentials.secret_key_base = nil
+      RUBY
+
+      error = assert_raise(ArgumentError) do
+        app "production"
+      end
+      assert_match(/Missing `secret_key_base`./, error.message)
+    end
+
+    test "raise when secret_key_base is not a type of string" do
+      add_to_config <<-RUBY
+        Rails.application.credentials.secret_key_base = 123
+      RUBY
 
       assert_raise(ArgumentError) do
-        app.key_generator
+        app "production"
       end
     end
 
     test "prefer secrets.secret_token over config.secret_token" do
-      app_file 'config/initializers/secret_token.rb', <<-RUBY
+      app_file "config/initializers/secret_token.rb", <<-RUBY
         Rails.application.config.secret_token = ""
       RUBY
-      app_file 'config/secrets.yml', <<-YAML
+      app_file "config/secrets.yml", <<-YAML
         development:
           secret_token: 3b7cd727ee24e8444053437c36cc66c3
       YAML
 
-      app 'development'
+      app "development"
 
-      assert_equal '3b7cd727ee24e8444053437c36cc66c3', app.secrets.secret_token
+      assert_equal "3b7cd727ee24e8444053437c36cc66c3", app.secrets.secret_token
     end
 
     test "application verifier can build different verifiers" do
       make_basic_app do |application|
-        application.secrets.secret_key_base = 'b3c631c314c0bbca50c1b2843150fe33'
+        application.credentials.secret_key_base = "b3c631c314c0bbca50c1b2843150fe33"
         application.config.session_store :disabled
       end
 
       default_verifier = app.message_verifier(:sensitive_value)
       text_verifier = app.message_verifier(:text)
 
-      message = text_verifier.generate('some_value')
+      message = text_verifier.generate("some_value")
 
-      assert_equal 'some_value', text_verifier.verify(message)
+      assert_equal "some_value", text_verifier.verify(message)
       assert_raises ActiveSupport::MessageVerifier::InvalidSignature do
         default_verifier.verify(message)
       end
@@ -506,135 +569,150 @@ module ApplicationTests
     end
 
     test "secrets.secret_key_base is used when config/secrets.yml is present" do
-      app_file 'config/secrets.yml', <<-YAML
+      app_file "config/secrets.yml", <<-YAML
         development:
           secret_key_base: 3b7cd727ee24e8444053437c36cc66c3
       YAML
 
-      app 'development'
-      assert_equal '3b7cd727ee24e8444053437c36cc66c3', app.secrets.secret_key_base
+      app "development"
+      assert_equal "3b7cd727ee24e8444053437c36cc66c3", app.secrets.secret_key_base
     end
 
     test "secret_key_base is copied from config to secrets when not set" do
       remove_file "config/secrets.yml"
-      app_file 'config/initializers/secret_token.rb', <<-RUBY
+      app_file "config/initializers/secret_token.rb", <<-RUBY
         Rails.application.config.secret_key_base = "3b7cd727ee24e8444053437c36cc66c3"
       RUBY
 
-      app 'development'
-      assert_equal '3b7cd727ee24e8444053437c36cc66c3', app.secrets.secret_key_base
+      app "development"
+      assert_equal "3b7cd727ee24e8444053437c36cc66c3", app.secrets.secret_key_base
     end
 
     test "config.secret_token over-writes a blank secrets.secret_token" do
-      app_file 'config/initializers/secret_token.rb', <<-RUBY
+      app_file "config/initializers/secret_token.rb", <<-RUBY
         Rails.application.config.secret_token = "b3c631c314c0bbca50c1b2843150fe33"
       RUBY
-      app_file 'config/secrets.yml', <<-YAML
+      app_file "config/secrets.yml", <<-YAML
         development:
           secret_key_base:
           secret_token:
       YAML
 
-      app 'development'
+      app "development"
 
-      assert_equal 'b3c631c314c0bbca50c1b2843150fe33', app.secrets.secret_token
-      assert_equal 'b3c631c314c0bbca50c1b2843150fe33', app.config.secret_token
+      assert_equal "b3c631c314c0bbca50c1b2843150fe33", app.secrets.secret_token
+      assert_equal "b3c631c314c0bbca50c1b2843150fe33", app.config.secret_token
     end
 
     test "custom secrets saved in config/secrets.yml are loaded in app secrets" do
-      app_file 'config/secrets.yml', <<-YAML
+      app_file "config/secrets.yml", <<-YAML
         development:
           secret_key_base: 3b7cd727ee24e8444053437c36cc66c3
           aws_access_key_id: myamazonaccesskeyid
           aws_secret_access_key: myamazonsecretaccesskey
       YAML
 
-      app 'development'
+      app "development"
 
-      assert_equal 'myamazonaccesskeyid', app.secrets.aws_access_key_id
-      assert_equal 'myamazonsecretaccesskey', app.secrets.aws_secret_access_key
+      assert_equal "myamazonaccesskeyid", app.secrets.aws_access_key_id
+      assert_equal "myamazonsecretaccesskey", app.secrets.aws_secret_access_key
     end
 
     test "shared secrets saved in config/secrets.yml are loaded in app secrets" do
-      app_file 'config/secrets.yml', <<-YAML
+      app_file "config/secrets.yml", <<-YAML
         shared:
           api_key: 3b7cd727
       YAML
 
-      app 'development'
+      app "development"
 
-      assert_equal '3b7cd727', app.secrets.api_key
+      assert_equal "3b7cd727", app.secrets.api_key
     end
 
     test "shared secrets will yield to environment specific secrets" do
-      app_file 'config/secrets.yml', <<-YAML
+      app_file "config/secrets.yml", <<-YAML
         shared:
           api_key: 3b7cd727
-        
+
         development:
           api_key: abc12345
       YAML
 
-      app 'development'
+      app "development"
 
-      assert_equal 'abc12345', app.secrets.api_key
+      assert_equal "abc12345", app.secrets.api_key
     end
 
     test "blank config/secrets.yml does not crash the loading process" do
-      app_file 'config/secrets.yml', <<-YAML
+      app_file "config/secrets.yml", <<-YAML
       YAML
 
-      app 'development'
+      app "development"
 
       assert_nil app.secrets.not_defined
     end
 
     test "config.secret_key_base over-writes a blank secrets.secret_key_base" do
-      app_file 'config/initializers/secret_token.rb', <<-RUBY
+      app_file "config/initializers/secret_token.rb", <<-RUBY
         Rails.application.config.secret_key_base = "iaminallyoursecretkeybase"
       RUBY
-      app_file 'config/secrets.yml', <<-YAML
+      app_file "config/secrets.yml", <<-YAML
         development:
           secret_key_base:
       YAML
 
-      app 'development'
+      app "development"
 
       assert_equal "iaminallyoursecretkeybase", app.secrets.secret_key_base
     end
 
     test "uses ActiveSupport::LegacyKeyGenerator as app.key_generator when secrets.secret_key_base is blank" do
-      app_file 'config/initializers/secret_token.rb', <<-RUBY
+      app_file "config/initializers/secret_token.rb", <<-RUBY
+        Rails.application.credentials.secret_key_base = nil
         Rails.application.config.secret_token = "b3c631c314c0bbca50c1b2843150fe33"
       RUBY
-      app_file 'config/secrets.yml', <<-YAML
-        development:
-          secret_key_base:
-      YAML
 
-      app 'development'
+      app "production"
 
-      assert_equal 'b3c631c314c0bbca50c1b2843150fe33', app.config.secret_token
-      assert_equal nil, app.secrets.secret_key_base
-      assert_equal app.key_generator.class, ActiveSupport::LegacyKeyGenerator
+      assert_equal "b3c631c314c0bbca50c1b2843150fe33", app.config.secret_token
+      assert_nil app.credentials.secret_key_base
+      assert_kind_of ActiveSupport::LegacyKeyGenerator, app.key_generator
     end
 
-    test "uses ActiveSupport::LegacyKeyGenerator with config.secret_token as app.key_generator when secrets.secret_key_base is blank" do
-      app_file 'config/initializers/secret_token.rb', <<-RUBY
-        Rails.application.config.secret_token = ""
-      RUBY
-      app_file 'config/secrets.yml', <<-YAML
+    test "that nested keys are symbolized the same as parents for hashes more than one level deep" do
+      app_file "config/secrets.yml", <<-YAML
         development:
-          secret_key_base:
+          smtp_settings:
+            address: "smtp.example.com"
+            user_name: "postmaster@example.com"
+            password: "697361616320736c6f616e2028656c6f7265737429"
       YAML
 
-      app 'development'
+      app "development"
 
-      assert_equal '', app.config.secret_token
-      assert_equal nil, app.secrets.secret_key_base
-      assert_raise ArgumentError, /\AA secret is required/ do
-        app.key_generator
+      assert_equal "697361616320736c6f616e2028656c6f7265737429", app.secrets.smtp_settings[:password]
+    end
+
+    test "require_master_key aborts app boot when missing key" do
+      skip "can't run without fork" unless Process.respond_to?(:fork)
+
+      remove_file "config/master.key"
+      add_to_config "config.require_master_key = true"
+
+      error = capture(:stderr) do
+        Process.wait(Process.fork { app "development" })
       end
+
+      assert_equal 1, $?.exitstatus
+      assert_match(/Missing.*RAILS_MASTER_KEY/, error)
+    end
+
+    test "credentials does not raise error when require_master_key is false and master key does not exist" do
+      remove_file "config/master.key"
+      add_to_config "config.require_master_key = false"
+      app "development"
+
+      assert_not app.credentials.secret_key_base
     end
 
     test "protect from forgery is the default in a new app" do
@@ -651,7 +729,7 @@ module ApplicationTests
     end
 
     test "default form builder specified as a string" do
-      app_file 'config/initializers/form_builder.rb', <<-RUBY
+      app_file "config/initializers/form_builder.rb", <<-RUBY
       class CustomFormBuilder < ActionView::Helpers::FormBuilder
         def text_field(attribute, *args)
           label(attribute) + super(attribute, *args)
@@ -660,15 +738,14 @@ module ApplicationTests
       Rails.configuration.action_view.default_form_builder = "CustomFormBuilder"
       RUBY
 
-      app_file 'app/models/post.rb', <<-RUBY
+      app_file "app/models/post.rb", <<-RUBY
       class Post
         include ActiveModel::Model
         attr_accessor :name
       end
       RUBY
 
-
-      app_file 'app/controllers/posts_controller.rb', <<-RUBY
+      app_file "app/controllers/posts_controller.rb", <<-RUBY
       class PostsController < ApplicationController
         def index
           render inline: "<%= begin; form_for(Post.new) {|f| f.text_field(:name)}; rescue => e; e.to_s; end %>"
@@ -682,14 +759,136 @@ module ApplicationTests
         end
       RUBY
 
-      app 'development'
+      app "development"
 
       get "/posts"
       assert_match(/label/, last_response.body)
     end
 
+    test "form_with can be configured with form_with_generates_ids" do
+      app_file "config/initializers/form_builder.rb", <<-RUBY
+      Rails.configuration.action_view.form_with_generates_ids = false
+      RUBY
+
+      app_file "app/models/post.rb", <<-RUBY
+      class Post
+        include ActiveModel::Model
+        attr_accessor :name
+      end
+      RUBY
+
+      app_file "app/controllers/posts_controller.rb", <<-RUBY
+      class PostsController < ApplicationController
+        def index
+          render inline: "<%= begin; form_with(model: Post.new) {|f| f.text_field(:name)}; rescue => e; e.to_s; end %>"
+        end
+      end
+      RUBY
+
+      add_to_config <<-RUBY
+        routes.prepend do
+          resources :posts
+        end
+      RUBY
+
+      app "development"
+
+      get "/posts"
+
+      assert_no_match(/id=('|")post_name('|")/, last_response.body)
+    end
+
+    test "form_with outputs ids by default" do
+      app_file "app/models/post.rb", <<-RUBY
+      class Post
+        include ActiveModel::Model
+        attr_accessor :name
+      end
+      RUBY
+
+      app_file "app/controllers/posts_controller.rb", <<-RUBY
+      class PostsController < ApplicationController
+        def index
+          render inline: "<%= begin; form_with(model: Post.new) {|f| f.text_field(:name)}; rescue => e; e.to_s; end %>"
+        end
+      end
+      RUBY
+
+      add_to_config <<-RUBY
+        routes.prepend do
+          resources :posts
+        end
+      RUBY
+
+      app "development"
+
+      get "/posts"
+
+      assert_match(/id=('|")post_name('|")/, last_response.body)
+    end
+
+    test "form_with can be configured with form_with_generates_remote_forms" do
+      app_file "config/initializers/form_builder.rb", <<-RUBY
+      Rails.configuration.action_view.form_with_generates_remote_forms = false
+      RUBY
+
+      app_file "app/models/post.rb", <<-RUBY
+      class Post
+        include ActiveModel::Model
+        attr_accessor :name
+      end
+      RUBY
+
+      app_file "app/controllers/posts_controller.rb", <<-RUBY
+      class PostsController < ApplicationController
+        def index
+          render inline: "<%= begin; form_with(model: Post.new) {|f| f.text_field(:name)}; rescue => e; e.to_s; end %>"
+        end
+      end
+      RUBY
+
+      add_to_config <<-RUBY
+        routes.prepend do
+          resources :posts
+        end
+      RUBY
+
+      app "development"
+
+      get "/posts"
+      assert_no_match(/data-remote/, last_response.body)
+    end
+
+    test "form_with generates remote forms by default" do
+      app_file "app/models/post.rb", <<-RUBY
+      class Post
+        include ActiveModel::Model
+        attr_accessor :name
+      end
+      RUBY
+
+      app_file "app/controllers/posts_controller.rb", <<-RUBY
+      class PostsController < ApplicationController
+        def index
+          render inline: "<%= begin; form_with(model: Post.new) {|f| f.text_field(:name)}; rescue => e; e.to_s; end %>"
+        end
+      end
+      RUBY
+
+      add_to_config <<-RUBY
+        routes.prepend do
+          resources :posts
+        end
+      RUBY
+
+      app "development"
+
+      get "/posts"
+      assert_match(/data-remote/, last_response.body)
+    end
+
     test "default method for update can be changed" do
-      app_file 'app/models/post.rb', <<-RUBY
+      app_file "app/models/post.rb", <<-RUBY
       class Post
         include ActiveModel::Model
         def to_key; [1]; end
@@ -699,14 +898,14 @@ module ApplicationTests
 
       token = "cf50faa3fe97702ca1ae"
 
-      app_file 'app/controllers/posts_controller.rb', <<-RUBY
+      app_file "app/controllers/posts_controller.rb", <<-RUBY
       class PostsController < ApplicationController
         def show
           render inline: "<%= begin; form_for(Post.new) {}; rescue => e; e.to_s; end %>"
         end
 
         def update
-          render text: "update"
+          render plain: "update"
         end
 
         private
@@ -721,7 +920,7 @@ module ApplicationTests
         end
       RUBY
 
-      app 'development'
+      app "development"
 
       params = { authenticity_token: token }
 
@@ -743,7 +942,7 @@ module ApplicationTests
 
     test "request forgery token param can be changed" do
       make_basic_app do |application|
-        application.config.action_controller.request_forgery_protection_token = '_xsrf_token_here'
+        application.config.action_controller.request_forgery_protection_token = "_xsrf_token_here"
       end
 
       class ::OmgController < ActionController::Base
@@ -774,12 +973,12 @@ module ApplicationTests
         config.action_mailer.interceptors = MyMailInterceptor
       RUBY
 
-      app 'development'
+      app "development"
 
       require "mail"
       _ = ActionMailer::Base
 
-      assert_equal [::MyMailInterceptor], ::Mail.send(:class_variable_get, "@@delivery_interceptors")
+      assert_equal [::MyMailInterceptor], ::Mail.class_variable_get(:@@delivery_interceptors)
     end
 
     test "registers multiple interceptors with ActionMailer" do
@@ -787,12 +986,12 @@ module ApplicationTests
         config.action_mailer.interceptors = [MyMailInterceptor, "MyOtherMailInterceptor"]
       RUBY
 
-      app 'development'
+      app "development"
 
       require "mail"
       _ = ActionMailer::Base
 
-      assert_equal [::MyMailInterceptor, ::MyOtherMailInterceptor], ::Mail.send(:class_variable_get, "@@delivery_interceptors")
+      assert_equal [::MyMailInterceptor, ::MyOtherMailInterceptor], ::Mail.class_variable_get(:@@delivery_interceptors)
     end
 
     test "registers preview interceptors with ActionMailer" do
@@ -800,7 +999,7 @@ module ApplicationTests
         config.action_mailer.preview_interceptors = MyPreviewMailInterceptor
       RUBY
 
-      app 'development'
+      app "development"
 
       require "mail"
       _ = ActionMailer::Base
@@ -813,7 +1012,7 @@ module ApplicationTests
         config.action_mailer.preview_interceptors = [MyPreviewMailInterceptor, "MyOtherPreviewMailInterceptor"]
       RUBY
 
-      app 'development'
+      app "development"
 
       require "mail"
       _ = ActionMailer::Base
@@ -822,11 +1021,11 @@ module ApplicationTests
     end
 
     test "default preview interceptor can be removed" do
-      app_file 'config/initializers/preview_interceptors.rb', <<-RUBY
+      app_file "config/initializers/preview_interceptors.rb", <<-RUBY
         ActionMailer::Base.preview_interceptors.delete(ActionMailer::InlinePreviewInterceptor)
       RUBY
 
-      app 'development'
+      app "development"
 
       require "mail"
       _ = ActionMailer::Base
@@ -839,12 +1038,12 @@ module ApplicationTests
         config.action_mailer.observers = MyMailObserver
       RUBY
 
-      app 'development'
+      app "development"
 
       require "mail"
       _ = ActionMailer::Base
 
-      assert_equal [::MyMailObserver], ::Mail.send(:class_variable_get, "@@delivery_notification_observers")
+      assert_equal [::MyMailObserver], ::Mail.class_variable_get(:@@delivery_notification_observers)
     end
 
     test "registers multiple observers with ActionMailer" do
@@ -852,12 +1051,12 @@ module ApplicationTests
         config.action_mailer.observers = [MyMailObserver, "MyOtherMailObserver"]
       RUBY
 
-      app 'development'
+      app "development"
 
       require "mail"
       _ = ActionMailer::Base
 
-      assert_equal [::MyMailObserver, ::MyOtherMailObserver], ::Mail.send(:class_variable_get, "@@delivery_notification_observers")
+      assert_equal [::MyMailObserver, ::MyOtherMailObserver], ::Mail.class_variable_get(:@@delivery_notification_observers)
     end
 
     test "allows setting the queue name for the ActionMailer::DeliveryJob" do
@@ -865,12 +1064,12 @@ module ApplicationTests
         config.action_mailer.deliver_later_queue_name = 'test_default'
       RUBY
 
-      app 'development'
+      app "development"
 
       require "mail"
       _ = ActionMailer::Base
 
-      assert_equal 'test_default', ActionMailer::Base.send(:class_variable_get, "@@deliver_later_queue_name")
+      assert_equal "test_default", ActionMailer::Base.class_variable_get(:@@deliver_later_queue_name)
     end
 
     test "valid timezone is setup correctly" do
@@ -879,7 +1078,7 @@ module ApplicationTests
         config.time_zone = "Wellington"
       RUBY
 
-      app 'development'
+      app "development"
 
       assert_equal "Wellington", Rails.application.config.time_zone
     end
@@ -891,7 +1090,7 @@ module ApplicationTests
       RUBY
 
       assert_raise(ArgumentError) do
-        app 'development'
+        app "development"
       end
     end
 
@@ -901,7 +1100,7 @@ module ApplicationTests
         config.beginning_of_week = :wednesday
       RUBY
 
-      app 'development'
+      app "development"
 
       assert_equal :wednesday, Rails.application.config.beginning_of_week
     end
@@ -913,15 +1112,15 @@ module ApplicationTests
       RUBY
 
       assert_raise(ArgumentError) do
-        app 'development'
+        app "development"
       end
     end
 
     test "config.action_view.cache_template_loading with cache_classes default" do
       add_to_config "config.cache_classes = true"
 
-      app 'development'
-      require 'action_view/base'
+      app "development"
+      require "action_view/base"
 
       assert_equal true, ActionView::Resolver.caching?
     end
@@ -929,8 +1128,8 @@ module ApplicationTests
     test "config.action_view.cache_template_loading without cache_classes default" do
       add_to_config "config.cache_classes = false"
 
-      app 'development'
-      require 'action_view/base'
+      app "development"
+      require "action_view/base"
 
       assert_equal false, ActionView::Resolver.caching?
     end
@@ -941,8 +1140,8 @@ module ApplicationTests
         config.action_view.cache_template_loading = false
       RUBY
 
-      app 'development'
-      require 'action_view/base'
+      app "development"
+      require "action_view/base"
 
       assert_equal false, ActionView::Resolver.caching?
     end
@@ -953,8 +1152,8 @@ module ApplicationTests
         config.action_view.cache_template_loading = true
       RUBY
 
-      app 'development'
-      require 'action_view/base'
+      app "development"
+      require "action_view/base"
 
       assert_equal true, ActionView::Resolver.caching?
     end
@@ -964,11 +1163,11 @@ module ApplicationTests
       add_to_env_config "development", "config.cache_classes = false"
 
       # These requires are to emulate an engine loading Action View before the application
-      require 'action_view'
-      require 'action_view/railtie'
-      require 'action_view/base'
+      require "action_view"
+      require "action_view/railtie"
+      require "action_view/base"
 
-      app 'development'
+      app "development"
 
       assert_equal false, ActionView::Resolver.caching?
     end
@@ -980,20 +1179,20 @@ module ApplicationTests
 
       class ::OmgController < ActionController::Base
         def index
-          render text: env["action_dispatch.show_exceptions"]
+          render plain: request.env["action_dispatch.show_exceptions"]
         end
       end
 
       get "/"
-      assert_equal 'true', last_response.body
+      assert_equal "true", last_response.body
     end
 
     test "config.action_controller.wrap_parameters is set in ActionController::Base" do
-      app_file 'config/initializers/wrap_parameters.rb', <<-RUBY
+      app_file "config/initializers/wrap_parameters.rb", <<-RUBY
         ActionController::Base.wrap_parameters format: [:json]
       RUBY
 
-      app_file 'app/models/post.rb', <<-RUBY
+      app_file "app/models/post.rb", <<-RUBY
       class Post
         def self.attribute_names
           %w(title)
@@ -1001,16 +1200,16 @@ module ApplicationTests
       end
       RUBY
 
-      app_file 'app/controllers/application_controller.rb', <<-RUBY
+      app_file "app/controllers/application_controller.rb", <<-RUBY
       class ApplicationController < ActionController::Base
         protect_from_forgery with: :reset_session # as we are testing API here
       end
       RUBY
 
-      app_file 'app/controllers/posts_controller.rb', <<-RUBY
+      app_file "app/controllers/posts_controller.rb", <<-RUBY
       class PostsController < ApplicationController
         def create
-          render text: params[:post].inspect
+          render plain: params[:post].inspect
         end
       end
       RUBY
@@ -1021,17 +1220,17 @@ module ApplicationTests
         end
       RUBY
 
-      app 'development'
+      app "development"
 
       post "/posts.json", '{ "title": "foo", "name": "bar" }', "CONTENT_TYPE" => "application/json"
       assert_equal '<ActionController::Parameters {"title"=>"foo"} permitted: false>', last_response.body
     end
 
     test "config.action_controller.permit_all_parameters = true" do
-      app_file 'app/controllers/posts_controller.rb', <<-RUBY
+      app_file "app/controllers/posts_controller.rb", <<-RUBY
       class PostsController < ActionController::Base
         def create
-          render text: params[:post].permitted? ? "permitted" : "forbidden"
+          render plain: params[:post].permitted? ? "permitted" : "forbidden"
         end
       end
       RUBY
@@ -1043,17 +1242,17 @@ module ApplicationTests
         config.action_controller.permit_all_parameters = true
       RUBY
 
-      app 'development'
+      app "development"
 
-      post "/posts", {post: {"title" =>"zomg"}}
-      assert_equal 'permitted', last_response.body
+      post "/posts", post: { "title" => "zomg" }
+      assert_equal "permitted", last_response.body
     end
 
     test "config.action_controller.action_on_unpermitted_parameters = :raise" do
-      app_file 'app/controllers/posts_controller.rb', <<-RUBY
+      app_file "app/controllers/posts_controller.rb", <<-RUBY
       class PostsController < ActionController::Base
         def create
-          render text: params.require(:post).permit(:name)
+          render plain: params.require(:post).permit(:name)
         end
       end
       RUBY
@@ -1065,16 +1264,23 @@ module ApplicationTests
         config.action_controller.action_on_unpermitted_parameters = :raise
       RUBY
 
-      app 'development'
+      app "development"
+
+      force_lazy_load_hooks { ActionController::Base }
+      force_lazy_load_hooks { ActionController::API }
 
       assert_equal :raise, ActionController::Parameters.action_on_unpermitted_parameters
 
-      post "/posts", {post: {"title" =>"zomg"}}
+      post "/posts", post: { "title" => "zomg" }
       assert_match "We're sorry, but something went wrong", last_response.body
     end
 
     test "config.action_controller.always_permitted_parameters are: controller, action by default" do
-      app 'development'
+      app "development"
+
+      force_lazy_load_hooks { ActionController::Base }
+      force_lazy_load_hooks { ActionController::API }
+
       assert_equal %w(controller action), ActionController::Parameters.always_permitted_parameters
     end
 
@@ -1083,16 +1289,19 @@ module ApplicationTests
         config.action_controller.always_permitted_parameters = %w( controller action format )
       RUBY
 
-      app 'development'
+      app "development"
+
+      force_lazy_load_hooks { ActionController::Base }
+      force_lazy_load_hooks { ActionController::API }
 
       assert_equal %w( controller action format ), ActionController::Parameters.always_permitted_parameters
     end
 
-    test "config.action_controller.always_permitted_parameters = ['controller','action','format'] does not raise exeception" do
-      app_file 'app/controllers/posts_controller.rb', <<-RUBY
+    test "config.action_controller.always_permitted_parameters = ['controller','action','format'] does not raise exception" do
+      app_file "app/controllers/posts_controller.rb", <<-RUBY
       class PostsController < ActionController::Base
         def create
-          render text: params.permit(post: [:title])
+          render plain: params.permit(post: [:title])
         end
       end
       RUBY
@@ -1105,32 +1314,87 @@ module ApplicationTests
         config.action_controller.action_on_unpermitted_parameters = :raise
       RUBY
 
-      app 'development'
+      app "development"
+
+      force_lazy_load_hooks { ActionController::Base }
+      force_lazy_load_hooks { ActionController::API }
 
       assert_equal :raise, ActionController::Parameters.action_on_unpermitted_parameters
 
-      post "/posts", {post: {"title" =>"zomg"}, format: "json"}
+      post "/posts", post: { "title" => "zomg" }, format: "json"
       assert_equal 200, last_response.status
     end
 
-    test "config.action_controller.action_on_unpermitted_parameters is :log by default on development" do
-      app 'development'
+    test "config.action_controller.action_on_unpermitted_parameters is :log by default in development" do
+      app "development"
+
+      force_lazy_load_hooks { ActionController::Base }
+      force_lazy_load_hooks { ActionController::API }
 
       assert_equal :log, ActionController::Parameters.action_on_unpermitted_parameters
     end
 
-    test "config.action_controller.action_on_unpermitted_parameters is :log by default on test" do
-      app 'test'
+    test "config.action_controller.action_on_unpermitted_parameters is :log by default in test" do
+      app "test"
+
+      force_lazy_load_hooks { ActionController::Base }
+      force_lazy_load_hooks { ActionController::API }
 
       assert_equal :log, ActionController::Parameters.action_on_unpermitted_parameters
     end
 
-    test "config.action_controller.action_on_unpermitted_parameters is false by default on production" do
-      app 'production'
+    test "config.action_controller.action_on_unpermitted_parameters is false by default in production" do
+      app "production"
+
+      force_lazy_load_hooks { ActionController::Base }
+      force_lazy_load_hooks { ActionController::API }
 
       assert_equal false, ActionController::Parameters.action_on_unpermitted_parameters
     end
 
+    test "config.action_controller.default_protect_from_forgery is true by default" do
+      app "development"
+
+      assert_equal true, ActionController::Base.default_protect_from_forgery
+      assert_includes ActionController::Base.__callbacks[:process_action].map(&:filter), :verify_authenticity_token
+    end
+
+    test "config.action_controller.permit_all_parameters can be configured in an initializer" do
+      app_file "config/initializers/permit_all_parameters.rb", <<-RUBY
+        Rails.application.config.action_controller.permit_all_parameters = true
+      RUBY
+
+      app "development"
+
+      force_lazy_load_hooks { ActionController::Base }
+      force_lazy_load_hooks { ActionController::API }
+      assert_equal true, ActionController::Parameters.permit_all_parameters
+    end
+
+    test "config.action_controller.always_permitted_parameters can be configured in an initializer" do
+      app_file "config/initializers/always_permitted_parameters.rb", <<-RUBY
+        Rails.application.config.action_controller.always_permitted_parameters = []
+      RUBY
+
+      app "development"
+
+      force_lazy_load_hooks { ActionController::Base }
+      force_lazy_load_hooks { ActionController::API }
+      assert_equal [], ActionController::Parameters.always_permitted_parameters
+    end
+
+    test "config.action_controller.action_on_unpermitted_parameters can be configured in an initializer" do
+      app_file "config/initializers/action_on_unpermitted_parameters.rb", <<-RUBY
+        Rails.application.config.action_controller.action_on_unpermitted_parameters = :raise
+      RUBY
+
+      app "development"
+
+      force_lazy_load_hooks { ActionController::Base }
+      force_lazy_load_hooks { ActionController::API }
+      assert_equal :raise, ActionController::Parameters.action_on_unpermitted_parameters
+    end
+
     test "config.action_dispatch.ignore_accept_header" do
       make_basic_app do |application|
         application.config.action_dispatch.ignore_accept_header = true
@@ -1139,28 +1403,27 @@ module ApplicationTests
       class ::OmgController < ActionController::Base
         def index
           respond_to do |format|
-            format.html { render text: "HTML" }
-            format.xml { render text: "XML" }
+            format.html { render plain: "HTML" }
+            format.xml { render plain: "XML" }
           end
         end
       end
 
-      get "/", {}, "HTTP_ACCEPT" => "application/xml"
-      assert_equal 'HTML', last_response.body
+      get "/", {}, { "HTTP_ACCEPT" => "application/xml" }
+      assert_equal "HTML", last_response.body
 
-      get "/", { format: :xml }, "HTTP_ACCEPT" => "application/xml"
-      assert_equal 'XML', last_response.body
+      get "/", { format: :xml }, { "HTTP_ACCEPT" => "application/xml" }
+      assert_equal "XML", last_response.body
     end
 
     test "Rails.application#env_config exists and include some existing parameters" do
       make_basic_app
 
-      assert_respond_to app, :env_config
-      assert_equal      app.env_config['action_dispatch.parameter_filter'],  app.config.filter_parameters
-      assert_equal      app.env_config['action_dispatch.show_exceptions'],   app.config.action_dispatch.show_exceptions
-      assert_equal      app.env_config['action_dispatch.logger'],            Rails.logger
-      assert_equal      app.env_config['action_dispatch.backtrace_cleaner'], Rails.backtrace_cleaner
-      assert_equal      app.env_config['action_dispatch.key_generator'],     Rails.application.key_generator
+      assert_equal      app.env_config["action_dispatch.parameter_filter"],  app.config.filter_parameters
+      assert_equal      app.env_config["action_dispatch.show_exceptions"],   app.config.action_dispatch.show_exceptions
+      assert_equal      app.env_config["action_dispatch.logger"],            Rails.logger
+      assert_equal      app.env_config["action_dispatch.backtrace_cleaner"], Rails.backtrace_cleaner
+      assert_equal      app.env_config["action_dispatch.key_generator"],     Rails.application.key_generator
     end
 
     test "config.colorize_logging default is true" do
@@ -1180,11 +1443,28 @@ module ApplicationTests
     end
 
     test "config.session_store with :active_record_store without activerecord-session_store gem" do
-      assert_raise RuntimeError, /activerecord-session_store/ do
+      e = assert_raise RuntimeError do
         make_basic_app do |application|
           application.config.session_store :active_record_store
         end
       end
+      assert_match(/activerecord-session_store/, e.message)
+    end
+
+    test "default session store initializer does not overwrite the user defined session store even if it is disabled" do
+      make_basic_app do |application|
+        application.config.session_store :disabled
+      end
+
+      assert_nil app.config.session_store
+    end
+
+    test "default session store initializer sets session store to cookie store" do
+      session_options = { key: "_myapp_session", cookie_only: true }
+      make_basic_app
+
+      assert_equal ActionDispatch::Session::CookieStore, app.config.session_store
+      assert_equal session_options, app.config.session_options
     end
 
     test "config.log_level with custom logger" do
@@ -1205,17 +1485,23 @@ module ApplicationTests
     test "config.active_record.dump_schema_after_migration is false on production" do
       build_app
 
-      app 'production'
+      app "production"
 
       assert_not ActiveRecord::Base.dump_schema_after_migration
     end
 
-    test "config.active_record.dump_schema_after_migration is true by default on development" do
-      app 'development'
+    test "config.active_record.dump_schema_after_migration is true by default in development" do
+      app "development"
 
       assert ActiveRecord::Base.dump_schema_after_migration
     end
 
+    test "config.active_record.verbose_query_logs is false by default in development" do
+      app "development"
+
+      assert_not ActiveRecord::Base.verbose_query_logs
+    end
+
     test "config.annotations wrapping SourceAnnotationExtractor::Annotation class" do
       make_basic_app do |application|
         application.config.annotations.register_extensions("coffee") do |tag|
@@ -1237,12 +1523,12 @@ module ApplicationTests
         end
       RUBY
 
-      app 'development'
+      app "development"
       assert_not Rails.configuration.ran_block
 
-      require 'rake'
-      require 'rake/testtask'
-      require 'rdoc/task'
+      require "rake"
+      require "rake/testtask"
+      require "rdoc/task"
 
       Rails.application.load_tasks
       assert Rails.configuration.ran_block
@@ -1259,7 +1545,7 @@ module ApplicationTests
         end
       RUBY
 
-      app 'development'
+      app "development"
       assert_not Rails.configuration.ran_block
 
       Rails.application.load_generators
@@ -1277,7 +1563,7 @@ module ApplicationTests
         end
       RUBY
 
-      app 'development'
+      app "development"
       assert_not Rails.configuration.ran_block
 
       Rails.application.load_console
@@ -1295,7 +1581,7 @@ module ApplicationTests
         end
       RUBY
 
-      app 'development'
+      app "development"
       assert_not Rails.configuration.ran_block
 
       Rails.application.load_runner
@@ -1303,7 +1589,7 @@ module ApplicationTests
     end
 
     test "loading the first existing database configuration available" do
-      app_file 'config/environments/development.rb', <<-RUBY
+      app_file "config/environments/development.rb", <<-RUBY
 
       Rails.application.configure do
         config.paths.add 'config/database', with: 'config/nonexistent.yml'
@@ -1311,44 +1597,78 @@ module ApplicationTests
         end
       RUBY
 
-      app 'development'
+      app "development"
 
       assert_kind_of Hash, Rails.application.config.database_configuration
     end
 
-    test 'raises with proper error message if no database configuration found' do
+    test "raises with proper error message if no database configuration found" do
       FileUtils.rm("#{app_path}/config/database.yml")
-      app 'development'
       err = assert_raises RuntimeError do
+        app "development"
         Rails.application.config.database_configuration
       end
-      assert_match 'config/database', err.message
+      assert_match "config/database", err.message
     end
 
-    test 'config.action_mailer.show_previews defaults to true in development' do
-      app 'development'
+    test "loads database.yml using shared keys" do
+      app_file "config/database.yml", <<-YAML
+        shared:
+          username: bobby
+          adapter: sqlite3
+
+        development:
+          database: 'dev_db'
+      YAML
+
+      app "development"
+
+      ar_config = Rails.application.config.database_configuration
+      assert_equal "sqlite3", ar_config["development"]["adapter"]
+      assert_equal "bobby",   ar_config["development"]["username"]
+      assert_equal "dev_db",  ar_config["development"]["database"]
+    end
+
+    test "loads database.yml using shared keys for undefined environments" do
+      app_file "config/database.yml", <<-YAML
+        shared:
+          username: bobby
+          adapter: sqlite3
+          database: 'dev_db'
+      YAML
+
+      app "development"
+
+      ar_config = Rails.application.config.database_configuration
+      assert_equal "sqlite3", ar_config["development"]["adapter"]
+      assert_equal "bobby",   ar_config["development"]["username"]
+      assert_equal "dev_db",  ar_config["development"]["database"]
+    end
+
+    test "config.action_mailer.show_previews defaults to true in development" do
+      app "development"
 
       assert Rails.application.config.action_mailer.show_previews
     end
 
-    test 'config.action_mailer.show_previews defaults to false in production' do
-      app 'production'
+    test "config.action_mailer.show_previews defaults to false in production" do
+      app "production"
 
       assert_equal false, Rails.application.config.action_mailer.show_previews
     end
 
-    test 'config.action_mailer.show_previews can be set in the configuration file' do
+    test "config.action_mailer.show_previews can be set in the configuration file" do
       add_to_config <<-RUBY
         config.action_mailer.show_previews = true
       RUBY
 
-      app 'production'
+      app "production"
 
       assert_equal true, Rails.application.config.action_mailer.show_previews
     end
 
     test "config_for loads custom configuration from yaml files" do
-      app_file 'config/custom.yml', <<-RUBY
+      app_file "config/custom.yml", <<-RUBY
       development:
         key: 'custom key'
       RUBY
@@ -1357,13 +1677,13 @@ module ApplicationTests
         config.my_custom_config = config_for('custom')
       RUBY
 
-      app 'development'
+      app "development"
 
-      assert_equal 'custom key', Rails.application.config.my_custom_config['key']
+      assert_equal "custom key", Rails.application.config.my_custom_config["key"]
     end
 
     test "config_for uses the Pathname object if it is provided" do
-      app_file 'config/custom.yml', <<-RUBY
+      app_file "config/custom.yml", <<-RUBY
       development:
         key: 'custom key'
       RUBY
@@ -1372,9 +1692,9 @@ module ApplicationTests
         config.my_custom_config = config_for(Pathname.new(Rails.root.join("config/custom.yml")))
       RUBY
 
-      app 'development'
+      app "development"
 
-      assert_equal 'custom key', Rails.application.config.my_custom_config['key']
+      assert_equal "custom key", Rails.application.config.my_custom_config["key"]
     end
 
     test "config_for raises an exception if the file does not exist" do
@@ -1383,14 +1703,14 @@ module ApplicationTests
       RUBY
 
       exception = assert_raises(RuntimeError) do
-        app 'development'
+        app "development"
       end
 
       assert_equal "Could not load configuration. No such file - #{app_path}/config/custom.yml", exception.message
     end
 
     test "config_for without the environment configured returns an empty hash" do
-      app_file 'config/custom.yml', <<-RUBY
+      app_file "config/custom.yml", <<-RUBY
       test:
         key: 'custom key'
       RUBY
@@ -1399,26 +1719,72 @@ module ApplicationTests
         config.my_custom_config = config_for('custom')
       RUBY
 
-      app 'development'
+      app "development"
 
       assert_equal({}, Rails.application.config.my_custom_config)
     end
 
     test "config_for with empty file returns an empty hash" do
-      app_file 'config/custom.yml', <<-RUBY
+      app_file "config/custom.yml", <<-RUBY
       RUBY
 
       add_to_config <<-RUBY
         config.my_custom_config = config_for('custom')
       RUBY
 
-      app 'development'
+      app "development"
 
       assert_equal({}, Rails.application.config.my_custom_config)
     end
 
+    test "default SQLite3Adapter.represent_boolean_as_integer for 5.1 is false" do
+      remove_from_config '.*config\.load_defaults.*\n'
+      add_to_top_of_config <<-RUBY
+        config.load_defaults 5.1
+      RUBY
+      app_file "app/models/post.rb", <<-RUBY
+        class Post < ActiveRecord::Base
+        end
+      RUBY
+
+      app "development"
+      force_lazy_load_hooks { Post }
+
+      assert_not ActiveRecord::ConnectionAdapters::SQLite3Adapter.represent_boolean_as_integer
+    end
+
+    test "default SQLite3Adapter.represent_boolean_as_integer for new installs is true" do
+      app_file "app/models/post.rb", <<-RUBY
+        class Post < ActiveRecord::Base
+        end
+      RUBY
+
+      app "development"
+      force_lazy_load_hooks { Post }
+
+      assert ActiveRecord::ConnectionAdapters::SQLite3Adapter.represent_boolean_as_integer
+    end
+
+    test "represent_boolean_as_integer should be able to set via config.active_record.sqlite3.represent_boolean_as_integer" do
+      remove_from_config '.*config\.load_defaults.*\n'
+
+      app_file "config/initializers/new_framework_defaults_5_2.rb", <<-RUBY
+        Rails.application.config.active_record.sqlite3.represent_boolean_as_integer = true
+      RUBY
+
+      app_file "app/models/post.rb", <<-RUBY
+        class Post < ActiveRecord::Base
+        end
+      RUBY
+
+      app "development"
+      force_lazy_load_hooks { Post }
+
+      assert ActiveRecord::ConnectionAdapters::SQLite3Adapter.represent_boolean_as_integer
+    end
+
     test "config_for containing ERB tags should evaluate" do
-      app_file 'config/custom.yml', <<-RUBY
+      app_file "config/custom.yml", <<-RUBY
       development:
         key: <%= 'custom key' %>
       RUBY
@@ -1427,13 +1793,13 @@ module ApplicationTests
         config.my_custom_config = config_for('custom')
       RUBY
 
-      app 'development'
+      app "development"
 
-      assert_equal 'custom key', Rails.application.config.my_custom_config['key']
+      assert_equal "custom key", Rails.application.config.my_custom_config["key"]
     end
 
     test "config_for with syntax error show a more descriptive exception" do
-      app_file 'config/custom.yml', <<-RUBY
+      app_file "config/custom.yml", <<-RUBY
       development:
         key: foo:
       RUBY
@@ -1443,14 +1809,14 @@ module ApplicationTests
       RUBY
 
       exception = assert_raises(RuntimeError) do
-        app 'development'
+        app "development"
       end
 
-      assert_match 'YAML syntax error occurred while parsing', exception.message
+      assert_match "YAML syntax error occurred while parsing", exception.message
     end
 
     test "config_for allows overriding the environment" do
-      app_file 'config/custom.yml', <<-RUBY
+      app_file "config/custom.yml", <<-RUBY
         test:
           key: 'walrus'
         production:
@@ -1462,11 +1828,11 @@ module ApplicationTests
       RUBY
       require "#{app_path}/config/environment"
 
-      assert_equal 'unicorn', Rails.application.config.my_custom_config['key']
+      assert_equal "unicorn", Rails.application.config.my_custom_config["key"]
     end
 
     test "api_only is false by default" do
-      app 'development'
+      app "development"
       refute Rails.application.config.api_only
     end
 
@@ -1474,7 +1840,7 @@ module ApplicationTests
       add_to_config <<-RUBY
         config.api_only = true
       RUBY
-      app 'development'
+      app "development"
 
       Rails.application.load_generators
       assert Rails.configuration.api_only
@@ -1484,7 +1850,7 @@ module ApplicationTests
       add_to_config <<-RUBY
         config.api_only = true
       RUBY
-      app 'development'
+      app "development"
 
       assert_equal :api, Rails.configuration.debug_exception_response_format
     end
@@ -1494,15 +1860,57 @@ module ApplicationTests
         config.api_only = true
       RUBY
 
-      app_file 'config/environments/development.rb', <<-RUBY
+      app_file "config/environments/development.rb", <<-RUBY
       Rails.application.configure do
         config.debug_exception_response_format = :default
       end
       RUBY
 
-      app 'development'
+      app "development"
 
       assert_equal :default, Rails.configuration.debug_exception_response_format
     end
+
+    test "controller force_ssl declaration can be used even if session_store is disabled" do
+      make_basic_app do |application|
+        application.config.session_store :disabled
+      end
+
+      class ::OmgController < ActionController::Base
+        force_ssl
+
+        def index
+          render plain: "Yay! You're on Rails!"
+        end
+      end
+
+      get "/"
+
+      assert_equal 301, last_response.status
+      assert_equal "https://example.org/", last_response.location
+    end
+
+    test "config.active_support.hash_digest_class is Digest::MD5 by default" do
+      app "development"
+
+      assert_equal Digest::MD5, ActiveSupport::Digest.hash_digest_class
+    end
+
+    test "config.active_support.hash_digest_class can be configured" do
+      app_file "config/environments/development.rb", <<-RUBY
+      Rails.application.configure do
+        config.active_support.hash_digest_class = Digest::SHA1
+      end
+      RUBY
+
+      app "development"
+
+      assert_equal Digest::SHA1, ActiveSupport::Digest.hash_digest_class
+    end
+
+    private
+      def force_lazy_load_hooks
+        yield # Tasty clarifying sugar, homie! We only need to reference a constant to load it.
+      end
   end
 end
diff --git a/railties/test/application/console_test.rb b/railties/test/application/console_test.rb
index ea68e63f8f..13164f49c2 100644
--- a/railties/test/application/console_test.rb
+++ b/railties/test/application/console_test.rb
@@ -1,11 +1,13 @@
-require 'isolation/abstract_unit'
+# frozen_string_literal: true
+
+require "isolation/abstract_unit"
+require "console_helpers"
 
 class ConsoleTest < ActiveSupport::TestCase
   include ActiveSupport::Testing::Isolation
 
   def setup
     build_app
-    boot_rails
   end
 
   def teardown
@@ -30,7 +32,7 @@ class ConsoleTest < ActiveSupport::TestCase
   end
 
   def test_app_can_access_path_helper_method
-    app_file 'config/routes.rb', <<-RUBY
+    app_file "config/routes.rb", <<-RUBY
       Rails.application.routes.draw do
         get 'foo', to: 'foo#index'
       end
@@ -38,7 +40,7 @@ class ConsoleTest < ActiveSupport::TestCase
 
     load_environment
     console_session = irb_context.app
-    assert_equal '/foo', console_session.foo_path
+    assert_equal "/foo", console_session.foo_path
   end
 
   def test_new_session_should_return_integration_session
@@ -89,22 +91,19 @@ class ConsoleTest < ActiveSupport::TestCase
     helper = irb_context.helper
     assert_not_nil helper
     assert_instance_of ActionView::Base, helper
-    assert_equal 'Once upon a time in a world...',
-      helper.truncate('Once upon a time in a world far far away')
+    assert_equal "Once upon a time in a world...",
+      helper.truncate("Once upon a time in a world far far away")
   end
 end
 
-begin
-  require "pty"
-rescue LoadError
-end
-
 class FullStackConsoleTest < ActiveSupport::TestCase
+  include ConsoleHelpers
+
   def setup
-    skip "PTY unavailable" unless defined?(PTY) && PTY.respond_to?(:open)
+    skip "PTY unavailable" unless available_pty?
 
     build_app
-    app_file 'app/models/post.rb', <<-CODE
+    app_file "app/models/post.rb", <<-CODE
       class Post < ActiveRecord::Base
       end
     CODE
@@ -117,48 +116,43 @@ class FullStackConsoleTest < ActiveSupport::TestCase
     teardown_app
   end
 
-  def assert_output(expected, timeout = 1)
-    timeout = Time.now + timeout
-
-    output = ""
-    until output.include?(expected) || Time.now > timeout
-      if IO.select([@master], [], [], 0.1)
-        output << @master.read(1)
-      end
-    end
-
-    assert output.include?(expected), "#{expected.inspect} expected, but got:\n\n#{output}"
-  end
-
   def write_prompt(command, expected_output = nil)
     @master.puts command
-    assert_output command
-    assert_output expected_output if expected_output
-    assert_output "> "
+    assert_output command, @master
+    assert_output expected_output, @master if expected_output
+    assert_output "> ", @master
   end
 
-  def spawn_console
+  def spawn_console(options)
     Process.spawn(
-      "#{app_path}/bin/rails console --sandbox",
+      "#{app_path}/bin/rails console #{options}",
       in: @slave, out: @slave, err: @slave
     )
 
-    assert_output "> ", 30
+    assert_output "> ", @master, 30
   end
 
   def test_sandbox
-    spawn_console
+    spawn_console("--sandbox")
 
     write_prompt "Post.count", "=> 0"
     write_prompt "Post.create"
     write_prompt "Post.count", "=> 1"
     @master.puts "quit"
 
-    spawn_console
+    spawn_console("--sandbox")
 
     write_prompt "Post.count", "=> 0"
     write_prompt "Post.transaction { Post.create; raise }"
     write_prompt "Post.count", "=> 0"
     @master.puts "quit"
   end
+
+  def test_environment_option_and_irb_option
+    spawn_console("test -- --verbose")
+
+    write_prompt "a = 1", "a = 1"
+    write_prompt "puts Rails.env", "puts Rails.env\r\ntest"
+    @master.puts "quit"
+  end
 end
diff --git a/railties/test/application/content_security_policy_test.rb b/railties/test/application/content_security_policy_test.rb
new file mode 100644
index 0000000000..97f2957c33
--- /dev/null
+++ b/railties/test/application/content_security_policy_test.rb
@@ -0,0 +1,197 @@
+# frozen_string_literal: true
+
+require "isolation/abstract_unit"
+require "rack/test"
+
+module ApplicationTests
+  class ContentSecurityPolicyTest < ActiveSupport::TestCase
+    include ActiveSupport::Testing::Isolation
+    include Rack::Test::Methods
+
+    def setup
+      build_app
+    end
+
+    def teardown
+      teardown_app
+    end
+
+    test "default content security policy is empty" do
+      controller :pages, <<-RUBY
+        class PagesController < ApplicationController
+          def index
+            render html: "<h1>Welcome to Rails!</h1>"
+          end
+        end
+      RUBY
+
+      app_file "config/routes.rb", <<-RUBY
+        Rails.application.routes.draw do
+          root to: "pages#index"
+        end
+      RUBY
+
+      app("development")
+
+      get "/"
+      assert_equal ";", last_response.headers["Content-Security-Policy"]
+    end
+
+    test "global content security policy in an initializer" do
+      controller :pages, <<-RUBY
+        class PagesController < ApplicationController
+          def index
+            render html: "<h1>Welcome to Rails!</h1>"
+          end
+        end
+      RUBY
+
+      app_file "config/initializers/content_security_policy.rb", <<-RUBY
+        Rails.application.config.content_security_policy do |p|
+          p.default_src :self, :https
+        end
+      RUBY
+
+      app_file "config/routes.rb", <<-RUBY
+        Rails.application.routes.draw do
+          root to: "pages#index"
+        end
+      RUBY
+
+      app("development")
+
+      get "/"
+      assert_policy "default-src 'self' https:;"
+    end
+
+    test "global report only content security policy in an initializer" do
+      controller :pages, <<-RUBY
+        class PagesController < ApplicationController
+          def index
+            render html: "<h1>Welcome to Rails!</h1>"
+          end
+        end
+      RUBY
+
+      app_file "config/initializers/content_security_policy.rb", <<-RUBY
+        Rails.application.config.content_security_policy do |p|
+          p.default_src :self, :https
+        end
+
+        Rails.application.config.content_security_policy_report_only = true
+      RUBY
+
+      app_file "config/routes.rb", <<-RUBY
+        Rails.application.routes.draw do
+          root to: "pages#index"
+        end
+      RUBY
+
+      app("development")
+
+      get "/"
+      assert_policy "default-src 'self' https:;", report_only: true
+    end
+
+    test "override content security policy in a controller" do
+      controller :pages, <<-RUBY
+        class PagesController < ApplicationController
+          content_security_policy do |p|
+            p.default_src "https://example.com"
+          end
+
+          def index
+            render html: "<h1>Welcome to Rails!</h1>"
+          end
+        end
+      RUBY
+
+      app_file "config/initializers/content_security_policy.rb", <<-RUBY
+        Rails.application.config.content_security_policy do |p|
+          p.default_src :self, :https
+        end
+      RUBY
+
+      app_file "config/routes.rb", <<-RUBY
+        Rails.application.routes.draw do
+          root to: "pages#index"
+        end
+      RUBY
+
+      app("development")
+
+      get "/"
+      assert_policy "default-src https://example.com;"
+    end
+
+    test "override content security policy to report only in a controller" do
+      controller :pages, <<-RUBY
+        class PagesController < ApplicationController
+          content_security_policy_report_only
+
+          def index
+            render html: "<h1>Welcome to Rails!</h1>"
+          end
+        end
+      RUBY
+
+      app_file "config/initializers/content_security_policy.rb", <<-RUBY
+        Rails.application.config.content_security_policy do |p|
+          p.default_src :self, :https
+        end
+      RUBY
+
+      app_file "config/routes.rb", <<-RUBY
+        Rails.application.routes.draw do
+          root to: "pages#index"
+        end
+      RUBY
+
+      app("development")
+
+      get "/"
+      assert_policy "default-src 'self' https:;", report_only: true
+    end
+
+    test "global content security policy added to rack app" do
+      app_file "config/initializers/content_security_policy.rb", <<-RUBY
+        Rails.application.config.content_security_policy do |p|
+          p.default_src :self, :https
+        end
+      RUBY
+
+      app_file "config/routes.rb", <<-RUBY
+        Rails.application.routes.draw do
+
+          app = ->(env) {
+            [200, { "Content-Type" => "text/html" }, ["<p>Hello, World!</p>"]]
+          }
+
+          root to: app
+        end
+      RUBY
+
+      app("development")
+
+      get "/"
+      assert_policy "default-src 'self' https:;"
+    end
+
+    private
+
+      def assert_policy(expected, report_only: false)
+        assert_equal 200, last_response.status
+
+        if report_only
+          expected_header = "Content-Security-Policy-Report-Only"
+          unexpected_header = "Content-Security-Policy"
+        else
+          expected_header = "Content-Security-Policy"
+          unexpected_header = "Content-Security-Policy-Report-Only"
+        end
+
+        assert_nil last_response.headers[unexpected_header]
+        assert_equal expected, last_response.headers[expected_header]
+      end
+  end
+end
diff --git a/railties/test/application/current_attributes_integration_test.rb b/railties/test/application/current_attributes_integration_test.rb
new file mode 100644
index 0000000000..146e96facc
--- /dev/null
+++ b/railties/test/application/current_attributes_integration_test.rb
@@ -0,0 +1,88 @@
+# frozen_string_literal: true
+
+require "isolation/abstract_unit"
+require "rack/test"
+
+class CurrentAttributesIntegrationTest < ActiveSupport::TestCase
+  include ActiveSupport::Testing::Isolation
+  include Rack::Test::Methods
+
+  setup do
+    build_app
+
+    app_file "app/models/current.rb", <<-RUBY
+      class Current < ActiveSupport::CurrentAttributes
+        attribute :customer
+
+        resets { Time.zone = "UTC" }
+
+        def customer=(customer)
+          super
+          Time.zone = customer.try(:time_zone)
+        end
+      end
+    RUBY
+
+    app_file "app/models/customer.rb", <<-RUBY
+      class Customer < Struct.new(:name)
+        def time_zone
+          "Copenhagen"
+        end
+      end
+    RUBY
+
+    app_file "config/routes.rb", <<-RUBY
+      Rails.application.routes.draw do
+        get "/customers/:action", controller: :customers
+      end
+    RUBY
+
+    app_file "app/controllers/customers_controller.rb", <<-RUBY
+      class CustomersController < ApplicationController
+        layout false
+
+        def set_current_customer
+          Current.customer = Customer.new("david")
+          render :index
+        end
+
+        def set_no_customer
+          render :index
+        end
+      end
+    RUBY
+
+    app_file "app/views/customers/index.html.erb", <<-RUBY
+      <%= Current.customer.try(:name) || 'noone' %>,<%= Time.zone.name %>
+    RUBY
+
+    require "#{app_path}/config/environment"
+  end
+
+  teardown :teardown_app
+
+  test "current customer is assigned and cleared" do
+    get "/customers/set_current_customer"
+    assert_equal 200, last_response.status
+    assert_match(/david,Copenhagen/, last_response.body)
+
+    get "/customers/set_no_customer"
+    assert_equal 200, last_response.status
+    assert_match(/noone,UTC/, last_response.body)
+  end
+
+  test "resets after execution" do
+    assert_nil Current.customer
+    assert_equal "UTC", Time.zone.name
+
+    Rails.application.executor.wrap do
+      Current.customer = Customer.new("david")
+
+      assert_equal "david", Current.customer.name
+      assert_equal "Copenhagen", Time.zone.name
+    end
+
+    assert_nil Current.customer
+    assert_equal "UTC", Time.zone.name
+  end
+end
diff --git a/railties/test/application/dbconsole_test.rb b/railties/test/application/dbconsole_test.rb
new file mode 100644
index 0000000000..8eb293c179
--- /dev/null
+++ b/railties/test/application/dbconsole_test.rb
@@ -0,0 +1,74 @@
+# frozen_string_literal: true
+
+require "isolation/abstract_unit"
+require "console_helpers"
+
+module ApplicationTests
+  class DBConsoleTest < ActiveSupport::TestCase
+    include ActiveSupport::Testing::Isolation
+    include ConsoleHelpers
+
+    def setup
+      skip "PTY unavailable" unless available_pty?
+
+      build_app
+    end
+
+    def teardown
+      teardown_app
+    end
+
+    def test_use_value_defined_in_environment_file_in_database_yml
+      app_file "config/database.yml", <<-YAML
+        development:
+           database: <%= Rails.application.config.database %>
+           adapter: sqlite3
+           pool: <%= ENV.fetch("RAILS_MAX_THREADS") { 5 } %>
+           timeout: 5000
+      YAML
+
+      app_file "config/environments/development.rb", <<-RUBY
+        Rails.application.configure do
+          config.database = "db/development.sqlite3"
+        end
+      RUBY
+
+      master, slave = PTY.open
+      spawn_dbconsole(slave)
+      assert_output("sqlite>", master)
+    ensure
+      master.puts ".exit"
+    end
+
+    def test_respect_environment_option
+      app_file "config/database.yml", <<-YAML
+        default: &default
+          adapter: sqlite3
+          pool: <%= ENV.fetch("RAILS_MAX_THREADS") { 5 } %>
+          timeout: 5000
+
+        development:
+          <<: *default
+          database: db/development.sqlite3
+
+        production:
+          <<: *default
+          database: db/production.sqlite3
+      YAML
+
+      master, slave = PTY.open
+      spawn_dbconsole(slave, "-e production")
+      assert_output("sqlite>", master)
+
+      master.puts "pragma database_list;"
+      assert_output("production.sqlite3", master)
+    ensure
+      master.puts ".exit"
+    end
+
+    private
+      def spawn_dbconsole(fd, options = nil)
+        Process.spawn("#{app_path}/bin/rails dbconsole #{options}", in: fd, out: fd, err: fd)
+      end
+  end
+end
diff --git a/railties/test/application/generators_test.rb b/railties/test/application/generators_test.rb
index 644af0e737..e5e557d204 100644
--- a/railties/test/application/generators_test.rb
+++ b/railties/test/application/generators_test.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require "isolation/abstract_unit"
 
 module ApplicationTests
@@ -6,7 +8,6 @@ module ApplicationTests
 
     def setup
       build_app
-      boot_rails
     end
 
     def teardown
@@ -30,7 +31,7 @@ module ApplicationTests
     end
 
     test "allow running plugin new generator inside Rails app directory" do
-      FileUtils.cd(rails_root){ `ruby bin/rails plugin new vendor/plugins/bukkits` }
+      rails "plugin", "new", "vendor/plugins/bukkits"
       assert File.exist?(File.join(rails_root, "vendor/plugins/bukkits/test/dummy/config/application.rb"))
     end
 
@@ -114,7 +115,7 @@ module ApplicationTests
     test "generators with string and hash for options should generate symbol keys" do
       with_bare_config do |c|
         c.generators do |g|
-          g.orm    'data_mapper', migration: false
+          g.orm    "data_mapper", migration: false
         end
 
         expected = {
@@ -135,10 +136,10 @@ module ApplicationTests
       require "#{app_path}/config/environment"
       Rails.application.load_generators
 
-      assert Rails::Generators.hidden_namespaces.include?("assets")
-      assert Rails::Generators.hidden_namespaces.include?("helper")
-      assert Rails::Generators.hidden_namespaces.include?("js")
-      assert Rails::Generators.hidden_namespaces.include?("css")
+      assert_includes Rails::Generators.hidden_namespaces, "assets"
+      assert_includes Rails::Generators.hidden_namespaces, "helper"
+      assert_includes Rails::Generators.hidden_namespaces, "js"
+      assert_includes Rails::Generators.hidden_namespaces, "css"
       assert Rails::Generators.options[:rails][:api]
       assert_equal false, Rails::Generators.options[:rails][:assets]
       assert_equal false, Rails::Generators.options[:rails][:helper]
@@ -166,9 +167,36 @@ module ApplicationTests
         config.api_only = true
       RUBY
 
-      FileUtils.cd(rails_root){ `bin/rails generate mailer notifier foo` }
+      rails "generate", "mailer", "notifier", "foo"
       assert File.exist?(File.join(rails_root, "app/views/notifier_mailer/foo.text.erb"))
       assert File.exist?(File.join(rails_root, "app/views/notifier_mailer/foo.html.erb"))
     end
+
+    test "ARGV is mutated as expected" do
+      require "#{app_path}/config/environment"
+      require "rails/command"
+      Rails::Command.const_set("APP_PATH", "rails/all")
+
+      FileUtils.cd(rails_root) do
+        ARGV = ["mailer", "notifier", "foo"]
+        Rails::Command.const_set("ARGV", ARGV)
+        quietly { Rails::Command.invoke :generate, ARGV }
+
+        assert_equal ["notifier", "foo"], ARGV
+      end
+
+      Rails::Command.send(:remove_const, "APP_PATH")
+    end
+
+    test "help does not show hidden namespaces and hidden commands" do
+      FileUtils.cd(rails_root) do
+        output = rails("generate", "--help")
+        assert_no_match "active_record:migration", output
+        assert_no_match "credentials", output
+
+        output = rails("destroy", "--help")
+        assert_no_match "active_record:migration", output
+      end
+    end
   end
 end
diff --git a/railties/test/application/help_test.rb b/railties/test/application/help_test.rb
new file mode 100644
index 0000000000..f728fc3b85
--- /dev/null
+++ b/railties/test/application/help_test.rb
@@ -0,0 +1,25 @@
+# frozen_string_literal: true
+
+require "isolation/abstract_unit"
+
+class HelpTest < ActiveSupport::TestCase
+  include ActiveSupport::Testing::Isolation
+
+  def setup
+    build_app
+  end
+
+  def teardown
+    teardown_app
+  end
+
+  test "command works" do
+    output = rails("help")
+    assert_match "The most common rails commands are", output
+  end
+
+  test "short-cut alias works" do
+    output = rails("-h")
+    assert_match "The most common rails commands are", output
+  end
+end
diff --git a/railties/test/application/initializers/frameworks_test.rb b/railties/test/application/initializers/frameworks_test.rb
index 44209a52f7..d2b77bd015 100644
--- a/railties/test/application/initializers/frameworks_test.rb
+++ b/railties/test/application/initializers/frameworks_test.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require "isolation/abstract_unit"
 
 module ApplicationTests
@@ -6,7 +8,6 @@ module ApplicationTests
 
     def setup
       build_app
-      boot_rails
       FileUtils.rm_rf "#{app_path}/config/environments"
     end
 
@@ -129,7 +130,7 @@ module ApplicationTests
         end
       RUBY
 
-      require 'rack/test'
+      require "rack/test"
       extend Rack::Test::Methods
 
       get "/foo/included_helpers"
@@ -161,10 +162,10 @@ module ApplicationTests
         end
       RUBY
 
-      require 'rack/test'
+      require "rack/test"
       extend Rack::Test::Methods
 
-      get 'omg/show'
+      get "omg/show"
       assert_equal '{"omg":"omg"}', last_response.body
     end
 
@@ -176,7 +177,7 @@ module ApplicationTests
     end
 
     test "assignment config.encoding to default_charset" do
-      charset = 'Shift_JIS'
+      charset = "Shift_JIS"
       add_to_config "config.encoding = '#{charset}'"
       require "#{app_path}/config/environment"
       assert_equal charset, ActionDispatch::Response.default_charset
@@ -186,7 +187,7 @@ module ApplicationTests
     test "if there's no config.active_support.bare, all of ActiveSupport is required" do
       use_frameworks []
       require "#{app_path}/config/environment"
-      assert_nothing_raised { [1,2,3].sample }
+      assert_nothing_raised { [1, 2, 3].sample }
     end
 
     test "config.active_support.bare does not require all of ActiveSupport" do
@@ -204,41 +205,35 @@ module ApplicationTests
     test "active_record extensions are applied to ActiveRecord" do
       add_to_config "config.active_record.table_name_prefix = 'tbl_'"
       require "#{app_path}/config/environment"
-      assert_equal 'tbl_', ActiveRecord::Base.table_name_prefix
+      assert_equal "tbl_", ActiveRecord::Base.table_name_prefix
     end
 
     test "database middleware doesn't initialize when activerecord is not in frameworks" do
       use_frameworks []
       require "#{app_path}/config/environment"
-      assert_nil defined?(ActiveRecord::Base)
+      assert !defined?(ActiveRecord::Base) || ActiveRecord.autoload?(:Base)
     end
 
     test "use schema cache dump" do
-      Dir.chdir(app_path) do
-        `rails generate model post title:string;
-         bin/rails db:migrate db:schema:cache:dump`
-      end
+      rails %w(generate model post title:string)
+      rails %w(db:migrate db:schema:cache:dump)
       require "#{app_path}/config/environment"
       ActiveRecord::Base.connection.drop_table("posts") # force drop posts table for test.
-      assert ActiveRecord::Base.connection.schema_cache.tables("posts")
+      assert ActiveRecord::Base.connection.schema_cache.data_sources("posts")
     end
 
     test "expire schema cache dump" do
-      Dir.chdir(app_path) do
-        `rails generate model post title:string;
-         bin/rails db:migrate db:schema:cache:dump db:rollback`
-      end
-      silence_warnings {
-        require "#{app_path}/config/environment"
-        assert !ActiveRecord::Base.connection.schema_cache.tables("posts")
-      }
+      rails %w(generate model post title:string)
+      rails %w(db:migrate db:schema:cache:dump db:rollback)
+      require "#{app_path}/config/environment"
+      assert !ActiveRecord::Base.connection.schema_cache.data_sources("posts")
     end
 
     test "active record establish_connection uses Rails.env if DATABASE_URL is not set" do
       begin
         require "#{app_path}/config/environment"
         orig_database_url = ENV.delete("DATABASE_URL")
-        orig_rails_env, Rails.env = Rails.env, 'development'
+        orig_rails_env, Rails.env = Rails.env, "development"
         ActiveRecord::Base.establish_connection
         assert ActiveRecord::Base.connection
         assert_match(/#{ActiveRecord::Base.configurations[Rails.env]['database']}/, ActiveRecord::Base.connection_config[:database])
@@ -253,7 +248,7 @@ module ApplicationTests
       begin
         require "#{app_path}/config/environment"
         orig_database_url = ENV.delete("DATABASE_URL")
-        orig_rails_env, Rails.env = Rails.env, 'development'
+        orig_rails_env, Rails.env = Rails.env, "development"
         database_url_db_name = "db/database_url_db.sqlite3"
         ENV["DATABASE_URL"] = "sqlite3:#{database_url_db_name}"
         ActiveRecord::Base.establish_connection
@@ -265,5 +260,13 @@ module ApplicationTests
         Rails.env = orig_rails_env if orig_rails_env
       end
     end
+
+    test "connections checked out during initialization are returned to the pool" do
+      app_file "config/initializers/active_record.rb", <<-RUBY
+        ActiveRecord::Base.connection
+      RUBY
+      require "#{app_path}/config/environment"
+      assert !ActiveRecord::Base.connection_pool.active_connection?
+    end
   end
 end
diff --git a/railties/test/application/initializers/hooks_test.rb b/railties/test/application/initializers/hooks_test.rb
index b2cea0a8e1..1e130c2f9e 100644
--- a/railties/test/application/initializers/hooks_test.rb
+++ b/railties/test/application/initializers/hooks_test.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require "isolation/abstract_unit"
 
 module ApplicationTests
@@ -6,7 +8,6 @@ module ApplicationTests
 
     def setup
       build_app
-      boot_rails
       FileUtils.rm_rf "#{app_path}/config/environments"
     end
 
@@ -32,7 +33,7 @@ module ApplicationTests
       RUBY
 
       require "#{app_path}/config/environment"
-      assert_equal [1,2,3], $initialization_callbacks
+      assert_equal [1, 2, 3], $initialization_callbacks
     end
 
     test "hooks block works correctly with eager_load" do
@@ -47,7 +48,7 @@ module ApplicationTests
       RUBY
 
       require "#{app_path}/config/environment"
-      assert_equal [1,2,3,4], $initialization_callbacks
+      assert_equal [1, 2, 3, 4], $initialization_callbacks
     end
 
     test "after_initialize runs after frameworks have been initialized" do
@@ -58,7 +59,7 @@ module ApplicationTests
 
       require "#{app_path}/config/environment"
       assert $activerecord_configurations
-      assert $activerecord_configurations['development']
+      assert $activerecord_configurations["development"]
     end
 
     test "after_initialize happens after to_prepare in development" do
diff --git a/railties/test/application/initializers/i18n_test.rb b/railties/test/application/initializers/i18n_test.rb
index 0f9bb41053..8058052771 100644
--- a/railties/test/application/initializers/i18n_test.rb
+++ b/railties/test/application/initializers/i18n_test.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require "isolation/abstract_unit"
 
 module ApplicationTests
@@ -6,7 +8,6 @@ module ApplicationTests
 
     def setup
       build_app
-      boot_rails
       FileUtils.rm_rf "#{app_path}/config/environments"
       require "rails/all"
     end
@@ -31,7 +32,7 @@ module ApplicationTests
     end
 
     def assert_no_fallbacks
-      assert !I18n.backend.class.included_modules.include?(I18n::Backend::Fallbacks)
+      assert_not_includes I18n.backend.class.included_modules, I18n::Backend::Fallbacks
     end
 
     # Locales
@@ -63,8 +64,8 @@ module ApplicationTests
         "#{app_path}/config/locales/en.yml", "#{app_path}/config/another_locale.yml"
       ], Rails.application.config.i18n.load_path
 
-      assert I18n.load_path.include?("#{app_path}/config/locales/en.yml")
-      assert I18n.load_path.include?("#{app_path}/config/another_locale.yml")
+      assert_includes I18n.load_path, "#{app_path}/config/locales/en.yml"
+      assert_includes I18n.load_path, "#{app_path}/config/another_locale.yml"
     end
 
     test "load_path is populated before eager loaded models" do
@@ -77,19 +78,19 @@ en:
   foo: "1"
       YAML
 
-      app_file 'app/models/foo.rb', <<-RUBY
+      app_file "app/models/foo.rb", <<-RUBY
         class Foo < ActiveRecord::Base
           @foo = I18n.t(:foo)
         end
       RUBY
 
-      app_file 'config/routes.rb', <<-RUBY
+      app_file "config/routes.rb", <<-RUBY
         Rails.application.routes.draw do
           get '/i18n',   :to => lambda { |env| [200, {}, [Foo.instance_variable_get('@foo')]] }
         end
       RUBY
 
-      require 'rack/test'
+      require "rack/test"
       extend Rack::Test::Methods
       load_app
 
@@ -107,13 +108,13 @@ en:
   foo: "1"
       YAML
 
-      app_file 'config/routes.rb', <<-RUBY
+      app_file "config/routes.rb", <<-RUBY
         Rails.application.routes.draw do
           get '/i18n',   :to => lambda { |env| [200, {}, [I18n.t(:foo)]] }
         end
       RUBY
 
-      require 'rack/test'
+      require "rack/test"
       extend Rack::Test::Methods
       load_app
 
@@ -142,13 +143,13 @@ en:
   foo: "1"
       YAML
 
-      app_file 'config/routes.rb', <<-RUBY
+      app_file "config/routes.rb", <<-RUBY
         Rails.application.routes.draw do
           get '/i18n',   :to => lambda { |env| [200, {}, [I18n.t(:foo)]] }
         end
       RUBY
 
-      require 'rack/test'
+      require "rack/test"
       extend Rack::Test::Methods
       load_app
 
@@ -178,13 +179,13 @@ en:
   foo: "1"
       YAML
 
-      app_file 'config/routes.rb', <<-RUBY
+      app_file "config/routes.rb", <<-RUBY
         Rails.application.routes.draw do
           get '/i18n',   :to => lambda { |env| [200, {}, [I18n.load_path.inspect]] }
         end
       RUBY
 
-      require 'rack/test'
+      require "rack/test"
       extend Rack::Test::Methods
       load_app
 
@@ -215,7 +216,7 @@ fr:
     test "config.i18n.fallbacks = true initializes I18n.fallbacks with default settings" do
       I18n::Railtie.config.i18n.fallbacks = true
       load_app
-      assert I18n.backend.class.included_modules.include?(I18n::Backend::Fallbacks)
+      assert_includes I18n.backend.class.included_modules, I18n::Backend::Fallbacks
       assert_fallbacks de: [:de, :en]
     end
 
@@ -223,7 +224,7 @@ fr:
       I18n::Railtie.config.i18n.fallbacks = true
       I18n::Railtie.config.i18n.backend = Class.new(I18n::Backend::Simple).new
       load_app
-      assert I18n.backend.class.included_modules.include?(I18n::Backend::Fallbacks)
+      assert_includes I18n.backend.class.included_modules, I18n::Backend::Fallbacks
       assert_fallbacks de: [:de, :en]
     end
 
@@ -234,7 +235,7 @@ fr:
     end
 
     test "config.i18n.fallbacks.map = { :ca => :'es-ES' } initializes fallbacks with a mapping ca => es-ES" do
-      I18n::Railtie.config.i18n.fallbacks.map = { :ca => :'es-ES' }
+      I18n::Railtie.config.i18n.fallbacks.map = { ca: :'es-ES' }
       load_app
       assert_fallbacks ca: [:ca, :"es-ES", :es, :en]
     end
@@ -246,13 +247,13 @@ fr:
     end
 
     test "[shortcut] config.i18n.fallbacks = [{ :ca => :'es-ES' }] initializes fallbacks with a mapping ca => es-ES" do
-      I18n::Railtie.config.i18n.fallbacks.map = { :ca => :'es-ES' }
+      I18n::Railtie.config.i18n.fallbacks = [{ ca: :'es-ES' }]
       load_app
       assert_fallbacks ca: [:ca, :"es-ES", :es, :en]
     end
 
     test "[shortcut] config.i18n.fallbacks = [:'en-US', { :ca => :'es-ES' }] initializes fallbacks with the given arguments" do
-      I18n::Railtie.config.i18n.fallbacks = [:'en-US', { :ca => :'es-ES' }]
+      I18n::Railtie.config.i18n.fallbacks = [:'en-US', { ca: :'es-ES' }]
       load_app
       assert_fallbacks ca: [:ca, :"es-ES", :es, :'en-US', :en]
     end
diff --git a/railties/test/application/initializers/load_path_test.rb b/railties/test/application/initializers/load_path_test.rb
index cd05956356..78cd4776d6 100644
--- a/railties/test/application/initializers/load_path_test.rb
+++ b/railties/test/application/initializers/load_path_test.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require "isolation/abstract_unit"
 
 module ApplicationTests
@@ -6,7 +8,6 @@ module ApplicationTests
 
     def setup
       build_app
-      boot_rails
       FileUtils.rm_rf "#{app_path}/config/environments"
     end
 
@@ -20,7 +21,7 @@ module ApplicationTests
       RUBY
 
       require "#{app_path}/config/environment"
-      assert $:.include?("#{app_path}/app/models")
+      assert_includes $:, "#{app_path}/app/models"
     end
 
     test "initializing an application allows to load code on lib path inside application class definition" do
@@ -37,7 +38,7 @@ module ApplicationTests
         require "#{app_path}/config/environment"
       end
 
-      assert $:.include?("#{app_path}/lib")
+      assert_includes $:, "#{app_path}/lib"
     end
 
     test "initializing an application eager load any path under app" do
diff --git a/railties/test/application/initializers/notifications_test.rb b/railties/test/application/initializers/notifications_test.rb
index 95655b74cf..c65c955734 100644
--- a/railties/test/application/initializers/notifications_test.rb
+++ b/railties/test/application/initializers/notifications_test.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require "isolation/abstract_unit"
 
 module ApplicationTests
@@ -6,7 +8,6 @@ module ApplicationTests
 
     def setup
       build_app
-      boot_rails
     end
 
     def teardown
@@ -31,6 +32,7 @@ module ApplicationTests
 
       logger = ActiveSupport::LogSubscriber::TestHelper::MockLogger.new
       ActiveRecord::Base.logger = logger
+      ActiveRecord::Base.verbose_query_logs = false
 
       # Mimic Active Record notifications
       instrument "sql.active_record", name: "SQL", sql: "SHOW tables"
@@ -40,17 +42,17 @@ module ApplicationTests
       assert_match(/SHOW tables/, logger.logged(:debug).last)
     end
 
-    test 'rails load_config_initializer event is instrumented' do
-      app_file 'config/initializers/foo.rb', ''
+    test "rails load_config_initializer event is instrumented" do
+      app_file "config/initializers/foo.rb", ""
 
       events = []
       callback = ->(*_) { events << _ }
-      ActiveSupport::Notifications.subscribed(callback, 'load_config_initializer.railties') do
+      ActiveSupport::Notifications.subscribed(callback, "load_config_initializer.railties") do
         app
       end
 
       assert_equal %w[load_config_initializer.railties], events.map(&:first)
-      assert_includes events.first.last[:initializer], 'config/initializers/foo.rb'
+      assert_includes events.first.last[:initializer], "config/initializers/foo.rb"
     end
   end
 end
diff --git a/railties/test/application/integration_test_case_test.rb b/railties/test/application/integration_test_case_test.rb
index d106d5159a..c08761092b 100644
--- a/railties/test/application/integration_test_case_test.rb
+++ b/railties/test/application/integration_test_case_test.rb
@@ -1,12 +1,14 @@
-require 'isolation/abstract_unit'
+# frozen_string_literal: true
+
+require "isolation/abstract_unit"
+require "env_helpers"
 
 module ApplicationTests
   class IntegrationTestCaseTest < ActiveSupport::TestCase
-    include ActiveSupport::Testing::Isolation
+    include ActiveSupport::Testing::Isolation, EnvHelpers
 
     setup do
       build_app
-      boot_rails
     end
 
     teardown do
@@ -14,9 +16,9 @@ module ApplicationTests
     end
 
     test "resets Action Mailer test deliveries" do
-      script('generate mailer BaseMailer welcome')
+      rails "generate", "mailer", "BaseMailer", "welcome"
 
-      app_file 'test/integration/mailer_integration_test.rb', <<-RUBY
+      app_file "test/integration/mailer_integration_test.rb", <<-RUBY
         require 'test_helper'
 
         class MailerIntegrationTest < ActionDispatch::IntegrationTest
@@ -38,8 +40,36 @@ module ApplicationTests
         end
       RUBY
 
-      output = Dir.chdir(app_path) { `bin/rails test 2>&1` }
-      assert_equal 0, $?.to_i, output
+      with_rails_env("test") { rails("db:migrate") }
+      output = rails("test")
+      assert_match(/0 failures, 0 errors/, output)
+    end
+  end
+
+  class IntegrationTestDefaultApp < ActiveSupport::TestCase
+    include ActiveSupport::Testing::Isolation, EnvHelpers
+
+    setup do
+      build_app
+    end
+
+    teardown do
+      teardown_app
+    end
+
+    test "app method of integration tests returns test_app by default" do
+      app_file "test/integration/default_app_test.rb", <<-RUBY
+        require 'test_helper'
+
+        class DefaultAppIntegrationTest < ActionDispatch::IntegrationTest
+          def test_app_returns_action_dispatch_test_app_by_default
+            assert_equal ActionDispatch.test_app, app
+          end
+        end
+      RUBY
+
+      with_rails_env("test") { rails("db:migrate") }
+      output = rails("test")
       assert_match(/0 failures, 0 errors/, output)
     end
   end
diff --git a/railties/test/application/loading_test.rb b/railties/test/application/loading_test.rb
index efb21ae473..de1e240fd3 100644
--- a/railties/test/application/loading_test.rb
+++ b/railties/test/application/loading_test.rb
@@ -1,11 +1,12 @@
-require 'isolation/abstract_unit'
+# frozen_string_literal: true
+
+require "isolation/abstract_unit"
 
 class LoadingTest < ActiveSupport::TestCase
   include ActiveSupport::Testing::Isolation
 
   def setup
     build_app
-    boot_rails
   end
 
   def teardown
@@ -26,11 +27,11 @@ class LoadingTest < ActiveSupport::TestCase
     require "#{rails_root}/config/environment"
     setup_ar!
 
-    p = Post.create(title: 'omg')
+    p = Post.create(title: "omg")
     assert_equal 1, Post.count
-    assert_equal 'omg', p.title
+    assert_equal "omg", p.title
     p = Post.first
-    assert_equal 'omg', p.title
+    assert_equal "omg", p.title
   end
 
   test "concerns in app are autoloaded" do
@@ -103,24 +104,24 @@ class LoadingTest < ActiveSupport::TestCase
       end
     MODEL
 
-    app_file 'config/routes.rb', <<-RUBY
+    app_file "config/routes.rb", <<-RUBY
       Rails.application.routes.draw do
         get '/load',   to: lambda { |env| [200, {}, Post.all] }
         get '/unload', to: lambda { |env| [200, {}, []] }
       end
     RUBY
 
-    require 'rack/test'
+    require "rack/test"
     extend Rack::Test::Methods
 
     require "#{rails_root}/config/environment"
     setup_ar!
 
-    assert_equal [ActiveRecord::SchemaMigration, ActiveRecord::InternalMetadata], ActiveRecord::Base.descendants
+    assert_equal [ActiveStorage::Blob, ActiveStorage::Attachment, ActiveRecord::SchemaMigration, ActiveRecord::InternalMetadata].collect(&:to_s).sort, ActiveRecord::Base.descendants.collect(&:to_s).sort
     get "/load"
-    assert_equal [ActiveRecord::SchemaMigration, ActiveRecord::InternalMetadata, Post], ActiveRecord::Base.descendants
+    assert_equal [ActiveStorage::Blob, ActiveStorage::Attachment, ActiveRecord::SchemaMigration, ActiveRecord::InternalMetadata, Post].collect(&:to_s).sort, ActiveRecord::Base.descendants.collect(&:to_s).sort
     get "/unload"
-    assert_equal [ActiveRecord::SchemaMigration, ActiveRecord::InternalMetadata], ActiveRecord::Base.descendants
+    assert_equal [ActiveStorage::Blob, ActiveStorage::Attachment, ActiveRecord::SchemaMigration, ActiveRecord::InternalMetadata].collect(&:to_s).sort, ActiveRecord::Base.descendants.collect(&:to_s).sort
   end
 
   test "initialize cant be called twice" do
@@ -133,7 +134,7 @@ class LoadingTest < ActiveSupport::TestCase
       config.cache_classes = false
     RUBY
 
-    app_file 'config/routes.rb', <<-RUBY
+    app_file "config/routes.rb", <<-RUBY
       Rails.application.routes.draw do
         get '/c', to: lambda { |env| [200, {"Content-Type" => "text/plain"}, [User.counter.to_s]] }
       end
@@ -145,7 +146,7 @@ class LoadingTest < ActiveSupport::TestCase
       end
     MODEL
 
-    require 'rack/test'
+    require "rack/test"
     extend Rack::Test::Methods
 
     require "#{rails_root}/config/environment"
@@ -174,7 +175,7 @@ class LoadingTest < ActiveSupport::TestCase
       end
     RUBY
 
-    app_file 'config/routes.rb', <<-RUBY
+    app_file "config/routes.rb", <<-RUBY
       Rails.application.routes.draw do
         get '/c', to: lambda { |env| [200, {"Content-Type" => "text/plain"}, [User.counter.to_s]] }
       end
@@ -186,7 +187,7 @@ class LoadingTest < ActiveSupport::TestCase
       end
     MODEL
 
-    require 'rack/test'
+    require "rack/test"
     extend Rack::Test::Methods
 
     require "#{rails_root}/config/environment"
@@ -209,7 +210,7 @@ class LoadingTest < ActiveSupport::TestCase
       config.cache_classes = false
     RUBY
 
-    app_file 'config/routes.rb', <<-RUBY
+    app_file "config/routes.rb", <<-RUBY
       $counter ||= 0
       Rails.application.routes.draw do
         get '/c', to: lambda { |env| User.name; [200, {"Content-Type" => "text/plain"}, [$counter.to_s]] }
@@ -222,7 +223,7 @@ class LoadingTest < ActiveSupport::TestCase
       end
     MODEL
 
-    require 'rack/test'
+    require "rack/test"
     extend Rack::Test::Methods
 
     require "#{rails_root}/config/environment"
@@ -241,7 +242,7 @@ class LoadingTest < ActiveSupport::TestCase
       config.cache_classes = false
     RUBY
 
-    app_file 'config/routes.rb', <<-RUBY
+    app_file "config/routes.rb", <<-RUBY
       $counter ||= 1
       $counter  *= 2
       Rails.application.routes.draw do
@@ -255,7 +256,7 @@ class LoadingTest < ActiveSupport::TestCase
       end
     MODEL
 
-    require 'rack/test'
+    require "rack/test"
     extend Rack::Test::Methods
 
     require "#{rails_root}/config/environment"
@@ -274,7 +275,7 @@ class LoadingTest < ActiveSupport::TestCase
       config.cache_classes = false
     RUBY
 
-    app_file 'config/routes.rb', <<-RUBY
+    app_file "config/routes.rb", <<-RUBY
       Rails.application.routes.draw do
         get '/title', to: lambda { |env| [200, {"Content-Type" => "text/plain"}, [Post.new.title]] }
         get '/body',  to: lambda { |env| [200, {"Content-Type" => "text/plain"}, [Post.new.body]] }
@@ -286,7 +287,7 @@ class LoadingTest < ActiveSupport::TestCase
       end
     MODEL
 
-    require 'rack/test'
+    require "rack/test"
     extend Rack::Test::Methods
 
     app_file "db/migrate/1_create_posts.rb", <<-MIGRATION
@@ -299,7 +300,7 @@ class LoadingTest < ActiveSupport::TestCase
       end
     MIGRATION
 
-    Dir.chdir(app_path) { `rake db:migrate`}
+    rails("db:migrate")
     require "#{rails_root}/config/environment"
 
     get "/title"
@@ -313,7 +314,7 @@ class LoadingTest < ActiveSupport::TestCase
       end
     MIGRATION
 
-    Dir.chdir(app_path) { `rake db:migrate` }
+    rails("db:migrate")
 
     get "/body"
     assert_equal "BODY", last_response.body
@@ -341,11 +342,11 @@ class LoadingTest < ActiveSupport::TestCase
 
     require "#{rails_root}/config/environment"
 
-    require 'rack/test'
+    require "rack/test"
     extend Rack::Test::Methods
 
-    get '/omg/show'
-    assert_equal 'OK', last_response.body
+    get "/omg/show"
+    assert_equal "OK", last_response.body
   end
 
   def test_initialize_can_be_called_at_any_time
@@ -358,15 +359,15 @@ class LoadingTest < ActiveSupport::TestCase
     assert Rails.application.initialized?
   end
 
-  protected
+  private
 
-  def setup_ar!
-    ActiveRecord::Base.establish_connection(adapter: "sqlite3", database: ":memory:")
-    ActiveRecord::Migration.verbose = false
-    ActiveRecord::Schema.define(version: 1) do
-      create_table :posts do |t|
-        t.string :title
+    def setup_ar!
+      ActiveRecord::Base.establish_connection(adapter: "sqlite3", database: ":memory:")
+      ActiveRecord::Migration.verbose = false
+      ActiveRecord::Schema.define(version: 1) do
+        create_table :posts do |t|
+          t.string :title
+        end
       end
     end
-  end
 end
diff --git a/railties/test/application/mailer_previews_test.rb b/railties/test/application/mailer_previews_test.rb
index 643d876a26..4e77cece1b 100644
--- a/railties/test/application/mailer_previews_test.rb
+++ b/railties/test/application/mailer_previews_test.rb
@@ -1,6 +1,8 @@
-require 'isolation/abstract_unit'
-require 'rack/test'
-require 'base64'
+# frozen_string_literal: true
+
+require "isolation/abstract_unit"
+require "rack/test"
+require "base64"
 
 module ApplicationTests
   class MailerPreviewsTest < ActiveSupport::TestCase
@@ -9,7 +11,6 @@ module ApplicationTests
 
     def setup
       build_app
-      boot_rails
     end
 
     def teardown
@@ -28,10 +29,10 @@ module ApplicationTests
       assert_equal 404, last_response.status
     end
 
-    test "/rails/mailers is accessible with correct configuraiton" do
+    test "/rails/mailers is accessible with correct configuration" do
       add_to_config "config.action_mailer.show_previews = true"
       app("production")
-      get "/rails/mailers", {}, {"REMOTE_ADDR" => "4.2.42.42"}
+      get "/rails/mailers", {}, { "REMOTE_ADDR" => "4.2.42.42" }
       assert_equal 200, last_response.status
     end
 
@@ -54,7 +55,7 @@ module ApplicationTests
     end
 
     test "mailer previews are loaded from the default preview_path" do
-      mailer 'notifier', <<-RUBY
+      mailer "notifier", <<-RUBY
         class Notifier < ActionMailer::Base
           default from: "from@example.com"
 
@@ -64,11 +65,11 @@ module ApplicationTests
         end
       RUBY
 
-      text_template 'notifier/foo', <<-RUBY
+      text_template "notifier/foo", <<-RUBY
         Hello, World!
       RUBY
 
-      mailer_preview 'notifier', <<-RUBY
+      mailer_preview "notifier", <<-RUBY
         class NotifierPreview < ActionMailer::Preview
           def foo
             Notifier.foo
@@ -76,7 +77,7 @@ module ApplicationTests
         end
       RUBY
 
-      app('development')
+      app("development")
 
       get "/rails/mailers"
       assert_match '<h3><a href="/rails/mailers/notifier">Notifier</a></h3>', last_response.body
@@ -86,7 +87,7 @@ module ApplicationTests
     test "mailer previews are loaded from a custom preview_path" do
       add_to_config "config.action_mailer.preview_path = '#{app_path}/lib/mailer_previews'"
 
-      mailer 'notifier', <<-RUBY
+      mailer "notifier", <<-RUBY
         class Notifier < ActionMailer::Base
           default from: "from@example.com"
 
@@ -96,11 +97,11 @@ module ApplicationTests
         end
       RUBY
 
-      text_template 'notifier/foo', <<-RUBY
+      text_template "notifier/foo", <<-RUBY
         Hello, World!
       RUBY
 
-      app_file 'lib/mailer_previews/notifier_preview.rb', <<-RUBY
+      app_file "lib/mailer_previews/notifier_preview.rb", <<-RUBY
         class NotifierPreview < ActionMailer::Preview
           def foo
             Notifier.foo
@@ -108,7 +109,7 @@ module ApplicationTests
         end
       RUBY
 
-      app('development')
+      app("development")
 
       get "/rails/mailers"
       assert_match '<h3><a href="/rails/mailers/notifier">Notifier</a></h3>', last_response.body
@@ -116,12 +117,12 @@ module ApplicationTests
     end
 
     test "mailer previews are reloaded across requests" do
-      app('development')
+      app("development")
 
       get "/rails/mailers"
       assert_no_match '<h3><a href="/rails/mailers/notifier">Notifier</a></h3>', last_response.body
 
-      mailer 'notifier', <<-RUBY
+      mailer "notifier", <<-RUBY
         class Notifier < ActionMailer::Base
           default from: "from@example.com"
 
@@ -131,11 +132,11 @@ module ApplicationTests
         end
       RUBY
 
-      text_template 'notifier/foo', <<-RUBY
+      text_template "notifier/foo", <<-RUBY
         Hello, World!
       RUBY
 
-      mailer_preview 'notifier', <<-RUBY
+      mailer_preview "notifier", <<-RUBY
         class NotifierPreview < ActionMailer::Preview
           def foo
             Notifier.foo
@@ -146,7 +147,7 @@ module ApplicationTests
       get "/rails/mailers"
       assert_match '<h3><a href="/rails/mailers/notifier">Notifier</a></h3>', last_response.body
 
-      remove_file 'test/mailers/previews/notifier_preview.rb'
+      remove_file "test/mailers/previews/notifier_preview.rb"
       sleep(1)
 
       get "/rails/mailers"
@@ -154,7 +155,7 @@ module ApplicationTests
     end
 
     test "mailer preview actions are added and removed" do
-      mailer 'notifier', <<-RUBY
+      mailer "notifier", <<-RUBY
         class Notifier < ActionMailer::Base
           default from: "from@example.com"
 
@@ -164,11 +165,11 @@ module ApplicationTests
         end
       RUBY
 
-      text_template 'notifier/foo', <<-RUBY
+      text_template "notifier/foo", <<-RUBY
         Hello, World!
       RUBY
 
-      mailer_preview 'notifier', <<-RUBY
+      mailer_preview "notifier", <<-RUBY
         class NotifierPreview < ActionMailer::Preview
           def foo
             Notifier.foo
@@ -176,14 +177,14 @@ module ApplicationTests
         end
       RUBY
 
-      app('development')
+      app("development")
 
       get "/rails/mailers"
       assert_match '<h3><a href="/rails/mailers/notifier">Notifier</a></h3>', last_response.body
       assert_match '<li><a href="/rails/mailers/notifier/foo">foo</a></li>', last_response.body
       assert_no_match '<li><a href="/rails/mailers/notifier/bar">bar</a></li>', last_response.body
 
-      mailer 'notifier', <<-RUBY
+      mailer "notifier", <<-RUBY
         class Notifier < ActionMailer::Base
           default from: "from@example.com"
 
@@ -197,15 +198,15 @@ module ApplicationTests
         end
       RUBY
 
-      text_template 'notifier/foo', <<-RUBY
+      text_template "notifier/foo", <<-RUBY
         Hello, World!
       RUBY
 
-      text_template 'notifier/bar', <<-RUBY
+      text_template "notifier/bar", <<-RUBY
         Goodbye, World!
       RUBY
 
-      mailer_preview 'notifier', <<-RUBY
+      mailer_preview "notifier", <<-RUBY
         class NotifierPreview < ActionMailer::Preview
           def foo
             Notifier.foo
@@ -224,7 +225,7 @@ module ApplicationTests
       assert_match '<li><a href="/rails/mailers/notifier/foo">foo</a></li>', last_response.body
       assert_match '<li><a href="/rails/mailers/notifier/bar">bar</a></li>', last_response.body
 
-      mailer 'notifier', <<-RUBY
+      mailer "notifier", <<-RUBY
         class Notifier < ActionMailer::Base
           default from: "from@example.com"
 
@@ -234,9 +235,9 @@ module ApplicationTests
         end
       RUBY
 
-      remove_file 'app/views/notifier/bar.text.erb'
+      remove_file "app/views/notifier/bar.text.erb"
 
-      mailer_preview 'notifier', <<-RUBY
+      mailer_preview "notifier", <<-RUBY
         class NotifierPreview < ActionMailer::Preview
           def foo
             Notifier.foo
@@ -255,12 +256,12 @@ module ApplicationTests
     test "mailer previews are reloaded from a custom preview_path" do
       add_to_config "config.action_mailer.preview_path = '#{app_path}/lib/mailer_previews'"
 
-      app('development')
+      app("development")
 
       get "/rails/mailers"
       assert_no_match '<h3><a href="/rails/mailers/notifier">Notifier</a></h3>', last_response.body
 
-      mailer 'notifier', <<-RUBY
+      mailer "notifier", <<-RUBY
         class Notifier < ActionMailer::Base
           default from: "from@example.com"
 
@@ -270,11 +271,11 @@ module ApplicationTests
         end
       RUBY
 
-      text_template 'notifier/foo', <<-RUBY
+      text_template "notifier/foo", <<-RUBY
         Hello, World!
       RUBY
 
-      app_file 'lib/mailer_previews/notifier_preview.rb', <<-RUBY
+      app_file "lib/mailer_previews/notifier_preview.rb", <<-RUBY
         class NotifierPreview < ActionMailer::Preview
           def foo
             Notifier.foo
@@ -285,7 +286,7 @@ module ApplicationTests
       get "/rails/mailers"
       assert_match '<h3><a href="/rails/mailers/notifier">Notifier</a></h3>', last_response.body
 
-      remove_file 'lib/mailer_previews/notifier_preview.rb'
+      remove_file "lib/mailer_previews/notifier_preview.rb"
       sleep(1)
 
       get "/rails/mailers"
@@ -293,14 +294,14 @@ module ApplicationTests
     end
 
     test "mailer preview not found" do
-      app('development')
+      app("development")
       get "/rails/mailers/notifier"
       assert last_response.not_found?
       assert_match "Mailer preview &#39;notifier&#39; not found", last_response.body
     end
 
     test "mailer preview email not found" do
-      mailer 'notifier', <<-RUBY
+      mailer "notifier", <<-RUBY
         class Notifier < ActionMailer::Base
           default from: "from@example.com"
 
@@ -310,11 +311,11 @@ module ApplicationTests
         end
       RUBY
 
-      text_template 'notifier/foo', <<-RUBY
+      text_template "notifier/foo", <<-RUBY
         Hello, World!
       RUBY
 
-      mailer_preview 'notifier', <<-RUBY
+      mailer_preview "notifier", <<-RUBY
         class NotifierPreview < ActionMailer::Preview
           def foo
             Notifier.foo
@@ -322,7 +323,7 @@ module ApplicationTests
         end
       RUBY
 
-      app('development')
+      app("development")
 
       get "/rails/mailers/notifier/bar"
       assert last_response.not_found?
@@ -330,7 +331,7 @@ module ApplicationTests
     end
 
     test "mailer preview NullMail" do
-      mailer 'notifier', <<-RUBY
+      mailer "notifier", <<-RUBY
         class Notifier < ActionMailer::Base
           default from: "from@example.com"
 
@@ -340,7 +341,7 @@ module ApplicationTests
         end
       RUBY
 
-      mailer_preview 'notifier', <<-RUBY
+      mailer_preview "notifier", <<-RUBY
         class NotifierPreview < ActionMailer::Preview
           def foo
             Notifier.foo
@@ -348,7 +349,7 @@ module ApplicationTests
         end
       RUBY
 
-      app('development')
+      app("development")
 
       get "/rails/mailers/notifier/foo"
       assert_match "You are trying to preview an email that does not have any content.", last_response.body
@@ -356,7 +357,7 @@ module ApplicationTests
     end
 
     test "mailer preview email part not found" do
-      mailer 'notifier', <<-RUBY
+      mailer "notifier", <<-RUBY
         class Notifier < ActionMailer::Base
           default from: "from@example.com"
 
@@ -366,11 +367,11 @@ module ApplicationTests
         end
       RUBY
 
-      text_template 'notifier/foo', <<-RUBY
+      text_template "notifier/foo", <<-RUBY
         Hello, World!
       RUBY
 
-      mailer_preview 'notifier', <<-RUBY
+      mailer_preview "notifier", <<-RUBY
         class NotifierPreview < ActionMailer::Preview
           def foo
             Notifier.foo
@@ -378,7 +379,7 @@ module ApplicationTests
         end
       RUBY
 
-      app('development')
+      app("development")
 
       get "/rails/mailers/notifier/foo?part=text%2Fhtml"
       assert last_response.not_found?
@@ -386,7 +387,7 @@ module ApplicationTests
     end
 
     test "message header uses full display names" do
-      mailer 'notifier', <<-RUBY
+      mailer "notifier", <<-RUBY
         class Notifier < ActionMailer::Base
           default from: "Ruby on Rails <core@rubyonrails.org>"
 
@@ -397,11 +398,11 @@ module ApplicationTests
         end
       RUBY
 
-      text_template 'notifier/foo', <<-RUBY
+      text_template "notifier/foo", <<-RUBY
         Hello, World!
       RUBY
 
-      mailer_preview 'notifier', <<-RUBY
+      mailer_preview "notifier", <<-RUBY
         class NotifierPreview < ActionMailer::Preview
           def foo
             Notifier.foo
@@ -409,7 +410,7 @@ module ApplicationTests
         end
       RUBY
 
-      app('development')
+      app("development")
 
       get "/rails/mailers/notifier/foo"
       assert_equal 200, last_response.status
@@ -419,7 +420,7 @@ module ApplicationTests
     end
 
     test "part menu selects correct option" do
-      mailer 'notifier', <<-RUBY
+      mailer "notifier", <<-RUBY
         class Notifier < ActionMailer::Base
           default from: "from@example.com"
 
@@ -429,15 +430,15 @@ module ApplicationTests
         end
       RUBY
 
-      html_template 'notifier/foo', <<-RUBY
+      html_template "notifier/foo", <<-RUBY
         <p>Hello, World!</p>
       RUBY
 
-      text_template 'notifier/foo', <<-RUBY
+      text_template "notifier/foo", <<-RUBY
         Hello, World!
       RUBY
 
-      mailer_preview 'notifier', <<-RUBY
+      mailer_preview "notifier", <<-RUBY
         class NotifierPreview < ActionMailer::Preview
           def foo
             Notifier.foo
@@ -445,7 +446,7 @@ module ApplicationTests
         end
       RUBY
 
-      app('development')
+      app("development")
 
       get "/rails/mailers/notifier/foo.html"
       assert_equal 200, last_response.status
@@ -457,7 +458,7 @@ module ApplicationTests
     end
 
     test "mailer previews create correct links when loaded on a subdirectory" do
-      mailer 'notifier', <<-RUBY
+      mailer "notifier", <<-RUBY
         class Notifier < ActionMailer::Base
           default from: "from@example.com"
 
@@ -467,11 +468,11 @@ module ApplicationTests
         end
       RUBY
 
-      text_template 'notifier/foo', <<-RUBY
+      text_template "notifier/foo", <<-RUBY
         Hello, World!
       RUBY
 
-      mailer_preview 'notifier', <<-RUBY
+      mailer_preview "notifier", <<-RUBY
         class NotifierPreview < ActionMailer::Preview
           def foo
             Notifier.foo
@@ -479,17 +480,68 @@ module ApplicationTests
         end
       RUBY
 
-      app('development')
+      app("development")
 
-      get "/rails/mailers", {}, 'SCRIPT_NAME' => '/my_app'
+      get "/rails/mailers", {}, { "SCRIPT_NAME" => "/my_app" }
       assert_match '<h3><a href="/my_app/rails/mailers/notifier">Notifier</a></h3>', last_response.body
       assert_match '<li><a href="/my_app/rails/mailers/notifier/foo">foo</a></li>', last_response.body
     end
 
+    test "mailer preview receives query params" do
+      mailer "notifier", <<-RUBY
+        class Notifier < ActionMailer::Base
+          default from: "from@example.com"
+
+          def foo(name)
+            @name = name
+            mail to: "to@example.org"
+          end
+        end
+      RUBY
+
+      html_template "notifier/foo", <<-RUBY
+        <p>Hello, <%= @name %>!</p>
+      RUBY
+
+      text_template "notifier/foo", <<-RUBY
+        Hello, <%= @name %>!
+      RUBY
+
+      mailer_preview "notifier", <<-RUBY
+        class NotifierPreview < ActionMailer::Preview
+          def foo
+            Notifier.foo(params[:name] || "World")
+          end
+        end
+      RUBY
+
+      app("development")
+
+      get "/rails/mailers/notifier/foo.txt"
+      assert_equal 200, last_response.status
+      assert_match '<iframe seamless name="messageBody" src="?part=text%2Fplain">', last_response.body
+      assert_match '<option selected value="?part=text%2Fplain">', last_response.body
+      assert_match '<option  value="?part=text%2Fhtml">', last_response.body
+
+      get "/rails/mailers/notifier/foo?part=text%2Fplain"
+      assert_equal 200, last_response.status
+      assert_match %r[Hello, World!], last_response.body
+
+      get "/rails/mailers/notifier/foo.html?name=Ruby"
+      assert_equal 200, last_response.status
+      assert_match '<iframe seamless name="messageBody" src="?name=Ruby&amp;part=text%2Fhtml">', last_response.body
+      assert_match '<option selected value="?name=Ruby&amp;part=text%2Fhtml">', last_response.body
+      assert_match '<option  value="?name=Ruby&amp;part=text%2Fplain">', last_response.body
+
+      get "/rails/mailers/notifier/foo?name=Ruby&part=text%2Fhtml"
+      assert_equal 200, last_response.status
+      assert_match %r[<p>Hello, Ruby!</p>], last_response.body
+    end
+
     test "plain text mailer preview with attachment" do
       image_file "pixel.png", "iVBORw0KGgoAAAANSUhEUgAAAAEAAAABAQMAAAAl21bKAAAAA1BMVEWzIioca/JlAAAACklEQVQI12NgAAAAAgAB4iG8MwAAAABJRU5ErkJgggo="
 
-      mailer 'notifier', <<-RUBY
+      mailer "notifier", <<-RUBY
         class Notifier < ActionMailer::Base
           default from: "from@example.com"
 
@@ -500,11 +552,11 @@ module ApplicationTests
         end
       RUBY
 
-      text_template 'notifier/foo', <<-RUBY
+      text_template "notifier/foo", <<-RUBY
         Hello, World!
       RUBY
 
-      mailer_preview 'notifier', <<-RUBY
+      mailer_preview "notifier", <<-RUBY
         class NotifierPreview < ActionMailer::Preview
           def foo
             Notifier.foo
@@ -512,7 +564,7 @@ module ApplicationTests
         end
       RUBY
 
-      app('development')
+      app("development")
 
       get "/rails/mailers/notifier/foo"
       assert_equal 200, last_response.status
@@ -526,7 +578,7 @@ module ApplicationTests
     test "multipart mailer preview with attachment" do
       image_file "pixel.png", "iVBORw0KGgoAAAANSUhEUgAAAAEAAAABAQMAAAAl21bKAAAAA1BMVEWzIioca/JlAAAACklEQVQI12NgAAAAAgAB4iG8MwAAAABJRU5ErkJgggo="
 
-      mailer 'notifier', <<-RUBY
+      mailer "notifier", <<-RUBY
         class Notifier < ActionMailer::Base
           default from: "from@example.com"
 
@@ -537,15 +589,15 @@ module ApplicationTests
         end
       RUBY
 
-      text_template 'notifier/foo', <<-RUBY
+      text_template "notifier/foo", <<-RUBY
         Hello, World!
       RUBY
 
-      html_template 'notifier/foo', <<-RUBY
+      html_template "notifier/foo", <<-RUBY
         <p>Hello, World!</p>
       RUBY
 
-      mailer_preview 'notifier', <<-RUBY
+      mailer_preview "notifier", <<-RUBY
         class NotifierPreview < ActionMailer::Preview
           def foo
             Notifier.foo
@@ -553,7 +605,7 @@ module ApplicationTests
         end
       RUBY
 
-      app('development')
+      app("development")
 
       get "/rails/mailers/notifier/foo"
       assert_equal 200, last_response.status
@@ -571,7 +623,7 @@ module ApplicationTests
     test "multipart mailer preview with inline attachment" do
       image_file "pixel.png", "iVBORw0KGgoAAAANSUhEUgAAAAEAAAABAQMAAAAl21bKAAAAA1BMVEWzIioca/JlAAAACklEQVQI12NgAAAAAgAB4iG8MwAAAABJRU5ErkJgggo="
 
-      mailer 'notifier', <<-RUBY
+      mailer "notifier", <<-RUBY
         class Notifier < ActionMailer::Base
           default from: "from@example.com"
 
@@ -582,16 +634,16 @@ module ApplicationTests
         end
       RUBY
 
-      text_template 'notifier/foo', <<-RUBY
+      text_template "notifier/foo", <<-RUBY
         Hello, World!
       RUBY
 
-      html_template 'notifier/foo', <<-RUBY
+      html_template "notifier/foo", <<-RUBY
         <p>Hello, World!</p>
         <%= image_tag attachments['pixel.png'].url %>
       RUBY
 
-      mailer_preview 'notifier', <<-RUBY
+      mailer_preview "notifier", <<-RUBY
         class NotifierPreview < ActionMailer::Preview
           def foo
             Notifier.foo
@@ -599,7 +651,7 @@ module ApplicationTests
         end
       RUBY
 
-      app('development')
+      app("development")
 
       get "/rails/mailers/notifier/foo"
       assert_equal 200, last_response.status
@@ -616,7 +668,7 @@ module ApplicationTests
     end
 
     test "multipart mailer preview with attached email" do
-      mailer 'notifier', <<-RUBY
+      mailer "notifier", <<-RUBY
         class Notifier < ActionMailer::Base
           default from: "from@example.com"
 
@@ -641,15 +693,15 @@ module ApplicationTests
         end
       RUBY
 
-      text_template 'notifier/foo', <<-RUBY
+      text_template "notifier/foo", <<-RUBY
         Hello, World!
       RUBY
 
-      html_template 'notifier/foo', <<-RUBY
+      html_template "notifier/foo", <<-RUBY
         <p>Hello, World!</p>
       RUBY
 
-      mailer_preview 'notifier', <<-RUBY
+      mailer_preview "notifier", <<-RUBY
         class NotifierPreview < ActionMailer::Preview
           def foo
             Notifier.foo
@@ -657,7 +709,7 @@ module ApplicationTests
         end
       RUBY
 
-      app('development')
+      app("development")
 
       get "/rails/mailers/notifier/foo"
       assert_equal 200, last_response.status
@@ -672,6 +724,40 @@ module ApplicationTests
       assert_match %r[<p>Hello, World!</p>], last_response.body
     end
 
+    test "multipart mailer preview with empty parts" do
+      mailer "notifier", <<-RUBY
+        class Notifier < ActionMailer::Base
+          default from: "from@example.com"
+
+          def foo
+            mail to: "to@example.org"
+          end
+        end
+      RUBY
+
+      text_template "notifier/foo", <<-RUBY
+      RUBY
+
+      html_template "notifier/foo", <<-RUBY
+      RUBY
+
+      mailer_preview "notifier", <<-RUBY
+        class NotifierPreview < ActionMailer::Preview
+          def foo
+            Notifier.foo
+          end
+        end
+      RUBY
+
+      app("development")
+
+      get "/rails/mailers/notifier/foo?part=text/plain"
+      assert_equal 200, last_response.status
+
+      get "/rails/mailers/notifier/foo?part=text/html"
+      assert_equal 200, last_response.status
+    end
+
     private
       def build_app
         super
@@ -695,7 +781,7 @@ module ApplicationTests
       end
 
       def image_file(name, contents)
-        app_file("public/images/#{name}", Base64.strict_decode64(contents), 'wb')
+        app_file("public/images/#{name}", Base64.strict_decode64(contents), "wb")
       end
   end
 end
diff --git a/railties/test/application/middleware/cache_test.rb b/railties/test/application/middleware/cache_test.rb
index c951dabd6c..9822ec563d 100644
--- a/railties/test/application/middleware/cache_test.rb
+++ b/railties/test/application/middleware/cache_test.rb
@@ -1,4 +1,6 @@
-require 'isolation/abstract_unit'
+# frozen_string_literal: true
+
+require "isolation/abstract_unit"
 
 module ApplicationTests
   class CacheTest < ActiveSupport::TestCase
@@ -6,8 +8,7 @@ module ApplicationTests
 
     def setup
       build_app
-      boot_rails
-      require 'rack/test'
+      require "rack/test"
       extend Rack::Test::Methods
     end
 
@@ -20,7 +21,7 @@ module ApplicationTests
         class ExpiresController < ApplicationController
           def expires_header
             expires_in 10, public: !params[:private]
-            render text: SecureRandom.hex(16)
+            render plain: SecureRandom.hex(16)
           end
 
           def expires_etag
@@ -33,18 +34,18 @@ module ApplicationTests
           end
 
           def keeps_if_modified_since
-            render :text => request.headers['If-Modified-Since']
+            render plain: request.headers['If-Modified-Since']
           end
         private
           def render_conditionally(headers)
             if stale?(headers.merge(public: !params[:private]))
-              render text: SecureRandom.hex(16)
+              render plain: SecureRandom.hex(16)
             end
           end
         end
       RUBY
 
-      app_file 'config/routes.rb', <<-RUBY
+      app_file "config/routes.rb", <<-RUBY
         Rails.application.routes.draw do
           get ':controller(/:action)'
         end
@@ -55,7 +56,7 @@ module ApplicationTests
       simple_controller
       expected = "Wed, 30 May 1984 19:43:31 GMT"
 
-      get "/expires/keeps_if_modified_since", {}, "HTTP_IF_MODIFIED_SINCE" => expected
+      get "/expires/keeps_if_modified_since", {}, { "HTTP_IF_MODIFIED_SINCE" => expected }
 
       assert_equal 200, last_response.status
       assert_equal expected, last_response.body, "cache should have kept If-Modified-Since"
@@ -66,12 +67,12 @@ module ApplicationTests
       app("development")
 
       get "/expires/expires_header"
-      assert_nil last_response.headers['X-Rack-Cache']
+      assert_nil last_response.headers["X-Rack-Cache"]
 
       body = last_response.body
 
       get "/expires/expires_header"
-      assert_nil last_response.headers['X-Rack-Cache']
+      assert_nil last_response.headers["X-Rack-Cache"]
       assert_not_equal body, last_response.body
     end
 
@@ -118,12 +119,12 @@ module ApplicationTests
       assert_equal "miss, store", last_response.headers["X-Rack-Cache"]
       assert_equal "public", last_response.headers["Cache-Control"]
 
-      body = last_response.body
       etag = last_response.headers["ETag"]
 
-      get "/expires/expires_etag", {}, "If-None-Match" => etag
+      get "/expires/expires_etag", {}, { "HTTP_IF_NONE_MATCH" => etag }
       assert_equal "stale, valid, store", last_response.headers["X-Rack-Cache"]
-      assert_equal body,                  last_response.body
+      assert_equal 304, last_response.status
+      assert_equal "", last_response.body
     end
 
     def test_cache_works_with_etags_private
@@ -138,7 +139,7 @@ module ApplicationTests
       body = last_response.body
       etag = last_response.headers["ETag"]
 
-      get "/expires/expires_etag", {private: true}, "If-None-Match" => etag
+      get "/expires/expires_etag", { private: true }, { "HTTP_IF_NONE_MATCH" => etag }
       assert_equal     "miss", last_response.headers["X-Rack-Cache"]
       assert_not_equal body,   last_response.body
     end
@@ -152,12 +153,12 @@ module ApplicationTests
       assert_equal "miss, store", last_response.headers["X-Rack-Cache"]
       assert_equal "public", last_response.headers["Cache-Control"]
 
-      body = last_response.body
       last = last_response.headers["Last-Modified"]
 
-      get "/expires/expires_last_modified", {}, "If-Modified-Since" => last
+      get "/expires/expires_last_modified", {}, { "HTTP_IF_MODIFIED_SINCE" => last }
       assert_equal "stale, valid, store", last_response.headers["X-Rack-Cache"]
-      assert_equal body,                  last_response.body
+      assert_equal 304, last_response.status
+      assert_equal "", last_response.body
     end
 
     def test_cache_works_with_last_modified_private
@@ -172,7 +173,7 @@ module ApplicationTests
       body = last_response.body
       last = last_response.headers["Last-Modified"]
 
-      get "/expires/expires_last_modified", {private: true}, "If-Modified-Since" => last
+      get "/expires/expires_last_modified", { private: true }, { "HTTP_IF_MODIFIED_SINCE" => last }
       assert_equal     "miss", last_response.headers["X-Rack-Cache"]
       assert_not_equal body,   last_response.body
     end
diff --git a/railties/test/application/middleware/cookies_test.rb b/railties/test/application/middleware/cookies_test.rb
index bbb7627be9..ecb4ee3446 100644
--- a/railties/test/application/middleware/cookies_test.rb
+++ b/railties/test/application/middleware/cookies_test.rb
@@ -1,8 +1,12 @@
-require 'isolation/abstract_unit'
+# frozen_string_literal: true
+
+require "isolation/abstract_unit"
+require "rack/test"
 
 module ApplicationTests
   class CookiesTest < ActiveSupport::TestCase
     include ActiveSupport::Testing::Isolation
+    include Rack::Test::Methods
 
     def new_app
       File.expand_path("#{app_path}/../new_app")
@@ -10,38 +14,180 @@ module ApplicationTests
 
     def setup
       build_app
-      boot_rails
       FileUtils.rm_rf("#{app_path}/config/environments")
     end
 
+    def app
+      Rails.application
+    end
+
     def teardown
       teardown_app
       FileUtils.rm_rf(new_app) if File.directory?(new_app)
     end
 
-    test 'always_write_cookie is true by default in development' do
-      require 'rails'
-      Rails.env = 'development'
+    test "always_write_cookie is true by default in development" do
+      require "rails"
+      Rails.env = "development"
       require "#{app_path}/config/environment"
       assert_equal true, ActionDispatch::Cookies::CookieJar.always_write_cookie
     end
 
-    test 'always_write_cookie is false by default in production' do
-      require 'rails'
-      Rails.env = 'production'
+    test "always_write_cookie is false by default in production" do
+      require "rails"
+      Rails.env = "production"
       require "#{app_path}/config/environment"
       assert_equal false, ActionDispatch::Cookies::CookieJar.always_write_cookie
     end
 
-    test 'always_write_cookie can be overridden' do
+    test "always_write_cookie can be overridden" do
       add_to_config <<-RUBY
         config.action_dispatch.always_write_cookie = false
       RUBY
 
-      require 'rails'
-      Rails.env = 'development'
+      require "rails"
+      Rails.env = "development"
       require "#{app_path}/config/environment"
       assert_equal false, ActionDispatch::Cookies::CookieJar.always_write_cookie
     end
+
+    test "signed cookies with SHA512 digest and rotated out SHA256 and SHA1 digests" do
+      app_file "config/routes.rb", <<-RUBY
+        Rails.application.routes.draw do
+          get  ':controller(/:action)'
+          post ':controller(/:action)'
+        end
+      RUBY
+
+      controller :foo, <<-RUBY
+        class FooController < ActionController::Base
+          protect_from_forgery with: :null_session
+
+          def write_raw_cookie_sha1
+            cookies[:signed_cookie] = TestVerifiers.sha1.generate("signed cookie")
+            head :ok
+          end
+
+          def write_raw_cookie_sha256
+            cookies[:signed_cookie] = TestVerifiers.sha256.generate("signed cookie")
+            head :ok
+          end
+
+          def read_signed
+            render plain: cookies.signed[:signed_cookie].inspect
+          end
+
+          def read_raw_cookie
+            render plain: cookies[:signed_cookie]
+          end
+        end
+      RUBY
+
+      add_to_config <<-RUBY
+        sha1_secret   = Rails.application.key_generator.generate_key("sha1")
+        sha256_secret = Rails.application.key_generator.generate_key("sha256")
+
+        ::TestVerifiers = Class.new do
+          class_attribute :sha1, default: ActiveSupport::MessageVerifier.new(sha1_secret, digest: "SHA1")
+          class_attribute :sha256, default: ActiveSupport::MessageVerifier.new(sha256_secret, digest: "SHA256")
+        end
+
+        config.action_dispatch.signed_cookie_digest = "SHA512"
+        config.action_dispatch.signed_cookie_salt = "sha512 salt"
+
+        config.action_dispatch.cookies_rotations.tap do |cookies|
+          cookies.rotate :signed, sha1_secret,   digest: "SHA1"
+          cookies.rotate :signed, sha256_secret, digest: "SHA256"
+        end
+      RUBY
+
+      require "#{app_path}/config/environment"
+
+      verifier_sha512 = ActiveSupport::MessageVerifier.new(app.key_generator.generate_key("sha512 salt"), digest: :SHA512)
+
+      get "/foo/write_raw_cookie_sha1"
+      get "/foo/read_signed"
+      assert_equal "signed cookie".inspect, last_response.body
+
+      get "/foo/read_raw_cookie"
+      assert_equal "signed cookie", verifier_sha512.verify(last_response.body)
+
+      get "/foo/write_raw_cookie_sha256"
+      get "/foo/read_signed"
+      assert_equal "signed cookie".inspect, last_response.body
+
+      get "/foo/read_raw_cookie"
+      assert_equal "signed cookie", verifier_sha512.verify(last_response.body)
+    end
+
+    test "encrypted cookies rotating multiple encryption keys" do
+      app_file "config/routes.rb", <<-RUBY
+        Rails.application.routes.draw do
+          get  ':controller(/:action)'
+          post ':controller(/:action)'
+        end
+      RUBY
+
+      controller :foo, <<-RUBY
+        class FooController < ActionController::Base
+          protect_from_forgery with: :null_session
+
+          def write_raw_cookie_one
+            cookies[:encrypted_cookie] = TestEncryptors.first_gcm.encrypt_and_sign("encrypted cookie")
+            head :ok
+          end
+
+          def write_raw_cookie_two
+            cookies[:encrypted_cookie] = TestEncryptors.second_gcm.encrypt_and_sign("encrypted cookie")
+            head :ok
+          end
+
+          def read_encrypted
+            render plain: cookies.encrypted[:encrypted_cookie].inspect
+          end
+
+          def read_raw_cookie
+            render plain: cookies[:encrypted_cookie]
+          end
+        end
+      RUBY
+
+      add_to_config <<-RUBY
+        first_secret  = Rails.application.key_generator.generate_key("first", 32)
+        second_secret = Rails.application.key_generator.generate_key("second", 32)
+
+        ::TestEncryptors = Class.new do
+          class_attribute :first_gcm,  default: ActiveSupport::MessageEncryptor.new(first_secret, cipher: "aes-256-gcm")
+          class_attribute :second_gcm, default: ActiveSupport::MessageEncryptor.new(second_secret, cipher: "aes-256-gcm")
+        end
+
+        config.action_dispatch.use_authenticated_cookie_encryption = true
+        config.action_dispatch.encrypted_cookie_cipher = "aes-256-gcm"
+        config.action_dispatch.authenticated_encrypted_cookie_salt = "salt"
+
+        config.action_dispatch.cookies_rotations.tap do |cookies|
+          cookies.rotate :encrypted, first_secret
+          cookies.rotate :encrypted, second_secret
+        end
+      RUBY
+
+      require "#{app_path}/config/environment"
+
+      encryptor = ActiveSupport::MessageEncryptor.new(app.key_generator.generate_key("salt", 32), cipher: "aes-256-gcm")
+
+      get "/foo/write_raw_cookie_one"
+      get "/foo/read_encrypted"
+      assert_equal "encrypted cookie".inspect, last_response.body
+
+      get "/foo/read_raw_cookie"
+      assert_equal "encrypted cookie", encryptor.decrypt_and_verify(last_response.body)
+
+      get "/foo/write_raw_cookie_sha256"
+      get "/foo/read_encrypted"
+      assert_equal "encrypted cookie".inspect, last_response.body
+
+      get "/foo/read_raw_cookie"
+      assert_equal "encrypted cookie", encryptor.decrypt_and_verify(last_response.body)
+    end
   end
 end
diff --git a/railties/test/application/middleware/exceptions_test.rb b/railties/test/application/middleware/exceptions_test.rb
index 639b01b562..2d659ade8d 100644
--- a/railties/test/application/middleware/exceptions_test.rb
+++ b/railties/test/application/middleware/exceptions_test.rb
@@ -1,5 +1,7 @@
-require 'isolation/abstract_unit'
-require 'rack/test'
+# frozen_string_literal: true
+
+require "isolation/abstract_unit"
+require "rack/test"
 
 module ApplicationTests
   class MiddlewareExceptionsTest < ActiveSupport::TestCase
@@ -8,7 +10,6 @@ module ApplicationTests
 
     def setup
       build_app
-      boot_rails
     end
 
     def teardown
@@ -70,7 +71,7 @@ module ApplicationTests
 
       app.config.action_dispatch.show_exceptions = true
 
-      get '/foo'
+      get "/foo"
       assert_equal 500, last_response.status
     end
 
@@ -78,7 +79,7 @@ module ApplicationTests
       app.config.action_dispatch.show_exceptions = false
 
       assert_raise(ActionController::RoutingError) do
-        get '/foo'
+        get "/foo"
       end
     end
 
@@ -86,7 +87,7 @@ module ApplicationTests
       app.config.action_dispatch.show_exceptions = true
 
       assert_nothing_raised do
-        get '/foo'
+        get "/foo"
         assert_match "The page you were looking for doesn't exist.", last_response.body
       end
     end
@@ -96,11 +97,25 @@ module ApplicationTests
       app.config.consider_all_requests_local = true
 
       assert_nothing_raised do
-        get '/foo'
+        get "/foo"
         assert_match "No route matches", last_response.body
       end
     end
 
+    test "routing to a nonexistent controller when action_dispatch.show_exceptions and consider_all_requests_local are set shows diagnostics" do
+      app_file "config/routes.rb", <<-RUBY
+        Rails.application.routes.draw do
+          resources :articles
+        end
+      RUBY
+
+      app.config.action_dispatch.show_exceptions = true
+      app.config.consider_all_requests_local = true
+
+      get "/articles"
+      assert_match "<title>Action Controller: Exception caught</title>", last_response.body
+    end
+
     test "displays diagnostics message when exception raised in template that contains UTF-8" do
       controller :foo, <<-RUBY
         class FooController < ActionController::Base
@@ -112,12 +127,12 @@ module ApplicationTests
       app.config.action_dispatch.show_exceptions = true
       app.config.consider_all_requests_local = true
 
-      app_file 'app/views/foo/index.html.erb', <<-ERB
+      app_file "app/views/foo/index.html.erb", <<-ERB
         <% raise 'boooom' %>
         ✓測試テスト시험
       ERB
 
-      get '/foo', :utf8 => '✓'
+      get "/foo", utf8: "✓"
       assert_match(/boooom/, last_response.body)
       assert_match(/測試テスト시험/, last_response.body)
     end
diff --git a/railties/test/application/middleware/remote_ip_test.rb b/railties/test/application/middleware/remote_ip_test.rb
index 37bd8a25c1..83cf8a27f7 100644
--- a/railties/test/application/middleware/remote_ip_test.rb
+++ b/railties/test/application/middleware/remote_ip_test.rb
@@ -1,6 +1,8 @@
-require 'ipaddr'
-require 'isolation/abstract_unit'
-require 'active_support/key_generator'
+# frozen_string_literal: true
+
+require "ipaddr"
+require "isolation/abstract_unit"
+require "active_support/key_generator"
 
 module ApplicationTests
   class RemoteIpTest < ActiveSupport::TestCase
@@ -9,8 +11,8 @@ module ApplicationTests
     def remote_ip(env = {})
       remote_ip = nil
       env = Rack::MockRequest.env_for("/").merge(env).merge!(
-        'action_dispatch.show_exceptions' => false,
-        'action_dispatch.key_generator'   => ActiveSupport::LegacyKeyGenerator.new('b3c631c314c0bbca50c1b2843150fe33')
+        "action_dispatch.show_exceptions" => false,
+        "action_dispatch.key_generator"   => ActiveSupport::LegacyKeyGenerator.new("b3c631c314c0bbca50c1b2843150fe33")
       )
 
       endpoint = Proc.new do |e|
@@ -69,7 +71,7 @@ module ApplicationTests
 
     test "the user can set trusted proxies with an IPAddr argument" do
       make_basic_app do |app|
-        app.config.action_dispatch.trusted_proxies = IPAddr.new('4.2.42.0/24')
+        app.config.action_dispatch.trusted_proxies = IPAddr.new("4.2.42.0/24")
       end
 
       assert_equal "1.1.1.1", remote_ip("REMOTE_ADDR" => "1.1.1.1", "HTTP_X_FORWARDED_FOR" => "10.0.0.0,4.2.42.42")
diff --git a/railties/test/application/middleware/sendfile_test.rb b/railties/test/application/middleware/sendfile_test.rb
index be86f1a3b8..9def3a0ce7 100644
--- a/railties/test/application/middleware/sendfile_test.rb
+++ b/railties/test/application/middleware/sendfile_test.rb
@@ -1,4 +1,6 @@
-require 'isolation/abstract_unit'
+# frozen_string_literal: true
+
+require "isolation/abstract_unit"
 
 module ApplicationTests
   class SendfileTest < ActiveSupport::TestCase
@@ -6,7 +8,6 @@ module ApplicationTests
 
     def setup
       build_app
-      boot_rails
       FileUtils.rm_rf "#{app_path}/config/environments"
     end
 
@@ -14,10 +15,6 @@ module ApplicationTests
       teardown_app
     end
 
-    def app
-      @app ||= Rails.application
-    end
-
     define_method :simple_controller do
       class ::OmgController < ActionController::Base
         def index
@@ -49,7 +46,7 @@ module ApplicationTests
 
     test "config.action_dispatch.x_sendfile_header is sent to Rack::Sendfile" do
       make_basic_app do |app|
-        app.config.action_dispatch.x_sendfile_header = 'X-Lighttpd-Send-File'
+        app.config.action_dispatch.x_sendfile_header = "X-Lighttpd-Send-File"
       end
 
       simple_controller
@@ -60,7 +57,7 @@ module ApplicationTests
 
     test "files handled by ActionDispatch::Static are handled by Rack::Sendfile" do
       make_basic_app do |app|
-        app.config.action_dispatch.x_sendfile_header = 'X-Sendfile'
+        app.config.action_dispatch.x_sendfile_header = "X-Sendfile"
         app.config.public_file_server.enabled = true
         app.paths["public"] = File.join(rails_root, "public")
       end
diff --git a/railties/test/application/middleware/session_test.rb b/railties/test/application/middleware/session_test.rb
index 85e7761727..a17988235a 100644
--- a/railties/test/application/middleware/session_test.rb
+++ b/railties/test/application/middleware/session_test.rb
@@ -1,5 +1,7 @@
-require 'isolation/abstract_unit'
-require 'rack/test'
+# frozen_string_literal: true
+
+require "isolation/abstract_unit"
+require "rack/test"
 
 module ApplicationTests
   class MiddlewareSessionTest < ActiveSupport::TestCase
@@ -8,7 +10,6 @@ module ApplicationTests
 
     def setup
       build_app
-      boot_rails
       FileUtils.rm_rf "#{app_path}/config/environments"
     end
 
@@ -54,7 +55,7 @@ module ApplicationTests
     end
 
     test "session is empty and isn't saved on unverified request when using :null_session protect method" do
-      app_file 'config/routes.rb', <<-RUBY
+      app_file "config/routes.rb", <<-RUBY
         Rails.application.routes.draw do
           get  ':controller(/:action)'
           post ':controller(/:action)'
@@ -71,7 +72,7 @@ module ApplicationTests
           end
 
           def read_session
-            render text: session[:foo].inspect
+            render plain: session[:foo].inspect
           end
         end
       RUBY
@@ -82,20 +83,20 @@ module ApplicationTests
 
       require "#{app_path}/config/environment"
 
-      get '/foo/write_session'
-      get '/foo/read_session'
-      assert_equal '1', last_response.body
+      get "/foo/write_session"
+      get "/foo/read_session"
+      assert_equal "1", last_response.body
 
-      post '/foo/read_session'               # Read session using POST request without CSRF token
-      assert_equal 'nil', last_response.body # Stored value shouldn't be accessible
+      post "/foo/read_session"               # Read session using POST request without CSRF token
+      assert_equal "nil", last_response.body # Stored value shouldn't be accessible
 
-      post '/foo/write_session' # Write session using POST request without CSRF token
-      get '/foo/read_session'   # Session shouldn't be changed
-      assert_equal '1', last_response.body
+      post "/foo/write_session" # Write session using POST request without CSRF token
+      get "/foo/read_session"   # Session shouldn't be changed
+      assert_equal "1", last_response.body
     end
 
     test "cookie jar is empty and isn't saved on unverified request when using :null_session protect method" do
-      app_file 'config/routes.rb', <<-RUBY
+      app_file "config/routes.rb", <<-RUBY
         Rails.application.routes.draw do
           get  ':controller(/:action)'
           post ':controller(/:action)'
@@ -112,7 +113,7 @@ module ApplicationTests
           end
 
           def read_cookie
-            render text: cookies[:foo].inspect
+            render plain: cookies[:foo].inspect
           end
         end
       RUBY
@@ -123,20 +124,20 @@ module ApplicationTests
 
       require "#{app_path}/config/environment"
 
-      get '/foo/write_cookie'
-      get '/foo/read_cookie'
+      get "/foo/write_cookie"
+      get "/foo/read_cookie"
       assert_equal '"1"', last_response.body
 
-      post '/foo/read_cookie'                # Read cookie using POST request without CSRF token
-      assert_equal 'nil', last_response.body # Stored value shouldn't be accessible
+      post "/foo/read_cookie"                # Read cookie using POST request without CSRF token
+      assert_equal "nil", last_response.body # Stored value shouldn't be accessible
 
-      post '/foo/write_cookie' # Write cookie using POST request without CSRF token
-      get '/foo/read_cookie'   # Cookie shouldn't be changed
+      post "/foo/write_cookie" # Write cookie using POST request without CSRF token
+      get "/foo/read_cookie"   # Cookie shouldn't be changed
       assert_equal '"1"', last_response.body
     end
 
     test "session using encrypted cookie store" do
-      app_file 'config/routes.rb', <<-RUBY
+      app_file "config/routes.rb", <<-RUBY
         Rails.application.routes.draw do
           get ':controller(/:action)'
         end
@@ -150,38 +151,43 @@ module ApplicationTests
           end
 
           def read_session
-            render text: session[:foo]
+            render plain: session[:foo]
           end
 
           def read_encrypted_cookie
-            render text: cookies.encrypted[:_myapp_session]['foo']
+            render plain: cookies.encrypted[:_myapp_session]['foo']
           end
 
           def read_raw_cookie
-            render text: cookies[:_myapp_session]
+            render plain: cookies[:_myapp_session]
           end
         end
       RUBY
 
+      add_to_config <<-RUBY
+        # Enable AEAD cookies
+        config.action_dispatch.use_authenticated_cookie_encryption = true
+      RUBY
+
       require "#{app_path}/config/environment"
 
-      get '/foo/write_session'
-      get '/foo/read_session'
-      assert_equal '1', last_response.body
+      get "/foo/write_session"
+      get "/foo/read_session"
+      assert_equal "1", last_response.body
 
-      get '/foo/read_encrypted_cookie'
-      assert_equal '1', last_response.body
+      get "/foo/read_encrypted_cookie"
+      assert_equal "1", last_response.body
 
-      secret = app.key_generator.generate_key('encrypted cookie')
-      sign_secret = app.key_generator.generate_key('signed encrypted cookie')
-      encryptor = ActiveSupport::MessageEncryptor.new(secret, sign_secret)
+      cipher = "aes-256-gcm"
+      secret = app.key_generator.generate_key("authenticated encrypted cookie")
+      encryptor = ActiveSupport::MessageEncryptor.new(secret[0, ActiveSupport::MessageEncryptor.key_len(cipher)], cipher: cipher)
 
-      get '/foo/read_raw_cookie'
-      assert_equal 1, encryptor.decrypt_and_verify(last_response.body)['foo']
+      get "/foo/read_raw_cookie"
+      assert_equal 1, encryptor.decrypt_and_verify(last_response.body)["foo"]
     end
 
     test "session upgrading signature to encryption cookie store works the same way as encrypted cookie store" do
-      app_file 'config/routes.rb', <<-RUBY
+      app_file "config/routes.rb", <<-RUBY
         Rails.application.routes.draw do
           get ':controller(/:action)'
         end
@@ -195,42 +201,45 @@ module ApplicationTests
           end
 
           def read_session
-            render text: session[:foo]
+            render plain: session[:foo]
           end
 
           def read_encrypted_cookie
-            render text: cookies.encrypted[:_myapp_session]['foo']
+            render plain: cookies.encrypted[:_myapp_session]['foo']
           end
 
           def read_raw_cookie
-            render text: cookies[:_myapp_session]
+            render plain: cookies[:_myapp_session]
           end
         end
       RUBY
 
       add_to_config <<-RUBY
         secrets.secret_token = "3b7cd727ee24e8444053437c36cc66c4"
+
+        # Enable AEAD cookies
+        config.action_dispatch.use_authenticated_cookie_encryption = true
       RUBY
 
       require "#{app_path}/config/environment"
 
-      get '/foo/write_session'
-      get '/foo/read_session'
-      assert_equal '1', last_response.body
+      get "/foo/write_session"
+      get "/foo/read_session"
+      assert_equal "1", last_response.body
 
-      get '/foo/read_encrypted_cookie'
-      assert_equal '1', last_response.body
+      get "/foo/read_encrypted_cookie"
+      assert_equal "1", last_response.body
 
-      secret = app.key_generator.generate_key('encrypted cookie')
-      sign_secret = app.key_generator.generate_key('signed encrypted cookie')
-      encryptor = ActiveSupport::MessageEncryptor.new(secret, sign_secret)
+      cipher = "aes-256-gcm"
+      secret = app.key_generator.generate_key("authenticated encrypted cookie")
+      encryptor = ActiveSupport::MessageEncryptor.new(secret[0, ActiveSupport::MessageEncryptor.key_len(cipher)], cipher: cipher)
 
-      get '/foo/read_raw_cookie'
-      assert_equal 1, encryptor.decrypt_and_verify(last_response.body)['foo']
+      get "/foo/read_raw_cookie"
+      assert_equal 1, encryptor.decrypt_and_verify(last_response.body)["foo"]
     end
 
     test "session upgrading signature to encryption cookie store upgrades session to encrypted mode" do
-      app_file 'config/routes.rb', <<-RUBY
+      app_file "config/routes.rb", <<-RUBY
         Rails.application.routes.draw do
           get ':controller(/:action)'
         end
@@ -250,46 +259,119 @@ module ApplicationTests
           end
 
           def read_session
-            render text: session[:foo]
+            render plain: session[:foo]
           end
 
           def read_encrypted_cookie
-            render text: cookies.encrypted[:_myapp_session]['foo']
+            render plain: cookies.encrypted[:_myapp_session]['foo']
           end
 
           def read_raw_cookie
-            render text: cookies[:_myapp_session]
+            render plain: cookies[:_myapp_session]
           end
         end
       RUBY
 
       add_to_config <<-RUBY
         secrets.secret_token = "3b7cd727ee24e8444053437c36cc66c4"
+
+        # Enable AEAD cookies
+        config.action_dispatch.use_authenticated_cookie_encryption = true
       RUBY
 
       require "#{app_path}/config/environment"
 
-      get '/foo/write_raw_session'
-      get '/foo/read_session'
-      assert_equal '1', last_response.body
+      get "/foo/write_raw_session"
+      get "/foo/read_session"
+      assert_equal "1", last_response.body
 
-      get '/foo/write_session'
-      get '/foo/read_session'
-      assert_equal '2', last_response.body
+      get "/foo/write_session"
+      get "/foo/read_session"
+      assert_equal "2", last_response.body
 
-      get '/foo/read_encrypted_cookie'
-      assert_equal '2', last_response.body
+      get "/foo/read_encrypted_cookie"
+      assert_equal "2", last_response.body
 
-      secret = app.key_generator.generate_key('encrypted cookie')
-      sign_secret = app.key_generator.generate_key('signed encrypted cookie')
-      encryptor = ActiveSupport::MessageEncryptor.new(secret, sign_secret)
+      cipher = "aes-256-gcm"
+      secret = app.key_generator.generate_key("authenticated encrypted cookie")
+      encryptor = ActiveSupport::MessageEncryptor.new(secret[0, ActiveSupport::MessageEncryptor.key_len(cipher)], cipher: cipher)
 
-      get '/foo/read_raw_cookie'
-      assert_equal 2, encryptor.decrypt_and_verify(last_response.body)['foo']
+      get "/foo/read_raw_cookie"
+      assert_equal 2, encryptor.decrypt_and_verify(last_response.body)["foo"]
+    end
+
+    test "session upgrading from AES-CBC-HMAC encryption to AES-GCM encryption" do
+      app_file "config/routes.rb", <<-RUBY
+        Rails.application.routes.draw do
+          get ':controller(/:action)'
+        end
+      RUBY
+
+      controller :foo, <<-RUBY
+        class FooController < ActionController::Base
+          def write_raw_session
+            # AES-256-CBC with SHA1 HMAC
+            # {"session_id"=>"1965d95720fffc123941bdfb7d2e6870", "foo"=>1}
+            cookies[:_myapp_session] = "TlgrdS85aUpDd1R2cDlPWlR6K0FJeGExckwySjZ2Z0pkR3d2QnRObGxZT25aalJWYWVvbFVLcHF4d0VQVDdSaFF2QjFPbG9MVjJzeWp3YjcyRUlKUUU2ZlR4bXlSNG9ZUkJPRUtld0E3dVU9LS0xNDZXbGpRZ3NjdW43N2haUEZJSUNRPT0=--3639b5ce54c09495cfeaae928cd5634e0c4b2e96"
+            head :ok
+          end
+
+          def write_session
+            session[:foo] = session[:foo] + 1
+            head :ok
+          end
+
+          def read_session
+            render plain: session[:foo]
+          end
+
+          def read_encrypted_cookie
+            render plain: cookies.encrypted[:_myapp_session]['foo']
+          end
+
+          def read_raw_cookie
+            render plain: cookies[:_myapp_session]
+          end
+        end
+      RUBY
+
+      add_to_config <<-RUBY
+        # Use a static key
+        Rails.application.credentials.secret_key_base = "known key base"
+
+        # Enable AEAD cookies
+        config.action_dispatch.use_authenticated_cookie_encryption = true
+      RUBY
+
+      begin
+        old_rails_env, ENV["RAILS_ENV"] = ENV["RAILS_ENV"], "production"
+
+        require "#{app_path}/config/environment"
+
+        get "/foo/write_raw_session"
+        get "/foo/read_session"
+        assert_equal "1", last_response.body
+
+        get "/foo/write_session"
+        get "/foo/read_session"
+        assert_equal "2", last_response.body
+
+        get "/foo/read_encrypted_cookie"
+        assert_equal "2", last_response.body
+
+        cipher = "aes-256-gcm"
+        secret = app.key_generator.generate_key("authenticated encrypted cookie")
+        encryptor = ActiveSupport::MessageEncryptor.new(secret[0, ActiveSupport::MessageEncryptor.key_len(cipher)], cipher: cipher)
+
+        get "/foo/read_raw_cookie"
+        assert_equal 2, encryptor.decrypt_and_verify(last_response.body)["foo"]
+      ensure
+        ENV["RAILS_ENV"] = old_rails_env
+      end
     end
 
     test "session upgrading legacy signed cookies to new signed cookies" do
-      app_file 'config/routes.rb', <<-RUBY
+      app_file "config/routes.rb", <<-RUBY
         Rails.application.routes.draw do
           get ':controller(/:action)'
         end
@@ -309,45 +391,51 @@ module ApplicationTests
           end
 
           def read_session
-            render text: session[:foo]
+            render plain: session[:foo]
           end
 
           def read_signed_cookie
-            render text: cookies.signed[:_myapp_session]['foo']
+            render plain: cookies.signed[:_myapp_session]['foo']
           end
 
           def read_raw_cookie
-            render text: cookies[:_myapp_session]
+            render plain: cookies[:_myapp_session]
           end
         end
       RUBY
 
       add_to_config <<-RUBY
         secrets.secret_token = "3b7cd727ee24e8444053437c36cc66c4"
-        secrets.secret_key_base = nil
+        Rails.application.credentials.secret_key_base = nil
       RUBY
 
-      require "#{app_path}/config/environment"
+      begin
+        old_rails_env, ENV["RAILS_ENV"] = ENV["RAILS_ENV"], "production"
+
+        require "#{app_path}/config/environment"
 
-      get '/foo/write_raw_session'
-      get '/foo/read_session'
-      assert_equal '1', last_response.body
+        get "/foo/write_raw_session"
+        get "/foo/read_session"
+        assert_equal "1", last_response.body
 
-      get '/foo/write_session'
-      get '/foo/read_session'
-      assert_equal '2', last_response.body
+        get "/foo/write_session"
+        get "/foo/read_session"
+        assert_equal "2", last_response.body
 
-      get '/foo/read_signed_cookie'
-      assert_equal '2', last_response.body
+        get "/foo/read_signed_cookie"
+        assert_equal "2", last_response.body
 
-      verifier = ActiveSupport::MessageVerifier.new(app.secrets.secret_token)
+        verifier = ActiveSupport::MessageVerifier.new(app.secrets.secret_token)
 
-      get '/foo/read_raw_cookie'
-      assert_equal 2, verifier.verify(last_response.body)['foo']
+        get "/foo/read_raw_cookie"
+        assert_equal 2, verifier.verify(last_response.body)["foo"]
+      ensure
+        ENV["RAILS_ENV"] = old_rails_env
+      end
     end
 
-    test 'calling reset_session on request does not trigger an error for API apps' do
-      add_to_config 'config.api_only = true'
+    test "calling reset_session on request does not trigger an error for API apps" do
+      add_to_config "config.api_only = true"
 
       controller :test, <<-RUBY
         class TestController < ApplicationController
@@ -358,7 +446,7 @@ module ApplicationTests
         end
       RUBY
 
-      app_file 'config/routes.rb', <<-RUBY
+      app_file "config/routes.rb", <<-RUBY
         Rails.application.routes.draw do
           get '/dump_flash' => "test#dump_flash"
         end
@@ -366,12 +454,18 @@ module ApplicationTests
 
       require "#{app_path}/config/environment"
 
-      get '/dump_flash'
+      get "/dump_flash"
 
       assert_equal 200, last_response.status
-      assert_equal 'It worked!', last_response.body
+      assert_equal "It worked!", last_response.body
 
-      refute Rails.application.middleware.include?(ActionDispatch::Flash)
+      assert_not_includes Rails.application.middleware, ActionDispatch::Flash
+    end
+
+    test "cookie_only is set to true even if user tries to overwrite it" do
+      add_to_config "config.session_store :cookie_store, key: '_myapp_session', cookie_only: false"
+      require "#{app_path}/config/environment"
+      assert app.config.session_options[:cookie_only], "Expected cookie_only to be set to true"
     end
   end
 end
diff --git a/railties/test/application/middleware/static_test.rb b/railties/test/application/middleware/static_test.rb
index 1246e20d94..0977042cfe 100644
--- a/railties/test/application/middleware/static_test.rb
+++ b/railties/test/application/middleware/static_test.rb
@@ -1,5 +1,7 @@
-require 'isolation/abstract_unit'
-require 'rack/test'
+# frozen_string_literal: true
+
+require "isolation/abstract_unit"
+require "rack/test"
 
 module ApplicationTests
   class MiddlewareStaticTest < ActiveSupport::TestCase
@@ -18,17 +20,17 @@ module ApplicationTests
     # Regression test to #8907
     # See https://github.com/rails/rails/commit/9cc82b77196d21a5c7021f6dca59ab9b2b158a45#commitcomment-2416514
     test "doesn't set Cache-Control header when it is nil" do
-      app_file "public/foo.html", 'static'
+      app_file "public/foo.html", "static"
 
       require "#{app_path}/config/environment"
 
-      get 'foo'
+      get "foo"
 
-      assert_not last_response.headers.has_key?('Cache-Control'), "Cache-Control should not be set"
+      assert_not last_response.headers.has_key?("Cache-Control"), "Cache-Control should not be set"
     end
 
     test "headers for static files are configurable" do
-      app_file "public/about.html", 'static'
+      app_file "public/about.html", "static"
       add_to_config <<-CONFIG
         config.public_file_server.headers = {
           "Access-Control-Allow-Origin" => "http://rubyonrails.org",
@@ -38,19 +40,19 @@ module ApplicationTests
 
       require "#{app_path}/config/environment"
 
-      get '/about.html'
+      get "/about.html"
 
-      assert_equal 'http://rubyonrails.org', last_response.headers["Access-Control-Allow-Origin"]
-      assert_equal 'public, max-age=60',     last_response.headers["Cache-Control"]
+      assert_equal "http://rubyonrails.org", last_response.headers["Access-Control-Allow-Origin"]
+      assert_equal "public, max-age=60",     last_response.headers["Cache-Control"]
     end
 
     test "public_file_server.index_name defaults to 'index'" do
       app_file "public/index.html", "/index.html"
-      
+
       require "#{app_path}/config/environment"
 
-      get '/'
-      
+      get "/"
+
       assert_equal "/index.html\n", last_response.body
     end
 
@@ -60,7 +62,7 @@ module ApplicationTests
 
       require "#{app_path}/config/environment"
 
-      get '/'
+      get "/"
 
       assert_equal "/other-index.html\n", last_response.body
     end
diff --git a/railties/test/application/middleware_test.rb b/railties/test/application/middleware_test.rb
index 7a86a96e19..d59384e982 100644
--- a/railties/test/application/middleware_test.rb
+++ b/railties/test/application/middleware_test.rb
@@ -1,4 +1,6 @@
-require 'isolation/abstract_unit'
+# frozen_string_literal: true
+
+require "isolation/abstract_unit"
 
 module ApplicationTests
   class MiddlewareTest < ActiveSupport::TestCase
@@ -6,7 +8,6 @@ module ApplicationTests
 
     def setup
       build_app
-      boot_rails
       FileUtils.rm_rf "#{app_path}/config/environments"
     end
 
@@ -31,16 +32,17 @@ module ApplicationTests
         "Rack::Runtime",
         "Rack::MethodOverride",
         "ActionDispatch::RequestId",
-        "Rails::Rack::Logger", # must come after Rack::MethodOverride to properly log overridden methods
+        "ActionDispatch::RemoteIp",
+        "Rails::Rack::Logger",
         "ActionDispatch::ShowExceptions",
         "ActionDispatch::DebugExceptions",
-        "ActionDispatch::RemoteIp",
         "ActionDispatch::Reloader",
         "ActionDispatch::Callbacks",
         "ActiveRecord::Migration::CheckPending",
         "ActionDispatch::Cookies",
         "ActionDispatch::Session::CookieStore",
         "ActionDispatch::Flash",
+        "ActionDispatch::ContentSecurityPolicy::Middleware",
         "Rack::Head",
         "Rack::ConditionalGet",
         "Rack::ETag"
@@ -59,10 +61,10 @@ module ApplicationTests
         "ActiveSupport::Cache::Strategy::LocalCache",
         "Rack::Runtime",
         "ActionDispatch::RequestId",
-        "Rails::Rack::Logger", # must come after Rack::MethodOverride to properly log overridden methods
+        "ActionDispatch::RemoteIp",
+        "Rails::Rack::Logger",
         "ActionDispatch::ShowExceptions",
         "ActionDispatch::DebugExceptions",
-        "ActionDispatch::RemoteIp",
         "ActionDispatch::Reloader",
         "ActionDispatch::Callbacks",
         "Rack::Head",
@@ -71,10 +73,41 @@ module ApplicationTests
       ], middleware
     end
 
+    test "middleware dependencies" do
+      boot!
+
+      # The following array-of-arrays describes dependencies between
+      # middlewares: the first item in each list depends on the
+      # remaining items (and therefore must occur later in the
+      # middleware stack).
+
+      dependencies = [
+        # Logger needs a fully "corrected" request environment
+        %w(Rails::Rack::Logger Rack::MethodOverride ActionDispatch::RequestId ActionDispatch::RemoteIp),
+
+        # Serving public/ doesn't invoke user code, so it should skip
+        # locks etc
+        %w(ActionDispatch::Executor ActionDispatch::Static),
+
+        # Errors during reload must be reported
+        %w(ActionDispatch::Reloader ActionDispatch::ShowExceptions ActionDispatch::DebugExceptions),
+
+        # Outright dependencies
+        %w(ActionDispatch::Static Rack::Sendfile),
+        %w(ActionDispatch::Flash ActionDispatch::Session::CookieStore),
+        %w(ActionDispatch::Session::CookieStore ActionDispatch::Cookies),
+      ]
+
+      require "tsort"
+      sorted = TSort.tsort((middleware | dependencies.flatten).method(:each),
+                           lambda { |n, &b| dependencies.each { |m, *ds| ds.each(&b) if m == n } })
+      assert_equal sorted, middleware
+    end
+
     test "Rack::Cache is not included by default" do
       boot!
 
-      assert !middleware.include?("Rack::Cache"), "Rack::Cache is not included in the default stack unless you set config.action_dispatch.rack_cache"
+      assert_not_includes middleware, "Rack::Cache", "Rack::Cache is not included in the default stack unless you set config.action_dispatch.rack_cache"
     end
 
     test "Rack::Cache is present when action_dispatch.rack_cache is set" do
@@ -82,7 +115,7 @@ module ApplicationTests
 
       boot!
 
-      assert middleware.include?("Rack::Cache")
+      assert_includes middleware, "Rack::Cache"
     end
 
     test "ActiveRecord::Migration::CheckPending is present when active_record.migration_error is set to :page_load" do
@@ -90,27 +123,27 @@ module ApplicationTests
 
       boot!
 
-      assert middleware.include?("ActiveRecord::Migration::CheckPending")
+      assert_includes middleware, "ActiveRecord::Migration::CheckPending"
     end
 
     test "ActionDispatch::SSL is present when force_ssl is set" do
       add_to_config "config.force_ssl = true"
       boot!
-      assert middleware.include?("ActionDispatch::SSL")
+      assert_includes middleware, "ActionDispatch::SSL"
     end
 
     test "ActionDispatch::SSL is configured with options when given" do
       add_to_config "config.force_ssl = true"
-      add_to_config "config.ssl_options = { host: 'example.com' }"
+      add_to_config "config.ssl_options = { redirect: { host: 'example.com' } }"
       boot!
 
-      assert_equal [{host: 'example.com'}], Rails.application.middleware.first.args
+      assert_equal [{ redirect: { host: "example.com" } }], Rails.application.middleware.first.args
     end
 
     test "removing Active Record omits its middleware" do
       use_frameworks []
       boot!
-      assert !middleware.include?("ActiveRecord::Migration::CheckPending")
+      assert_not_includes middleware, "ActiveRecord::Migration::CheckPending"
     end
 
     test "includes executor" do
@@ -140,20 +173,20 @@ module ApplicationTests
     test "removes static asset server if public_file_server.enabled is disabled" do
       add_to_config "config.public_file_server.enabled = false"
       boot!
-      assert !middleware.include?("ActionDispatch::Static")
+      assert_not_includes middleware, "ActionDispatch::Static"
     end
 
     test "can delete a middleware from the stack" do
       add_to_config "config.middleware.delete ActionDispatch::Static"
       boot!
-      assert !middleware.include?("ActionDispatch::Static")
+      assert_not_includes middleware, "ActionDispatch::Static"
     end
 
     test "can delete a middleware from the stack even if insert_before is added after delete" do
       add_to_config "config.middleware.delete Rack::Runtime"
       add_to_config "config.middleware.insert_before(Rack::Runtime, Rack::Config)"
       boot!
-      assert middleware.include?("Rack::Config")
+      assert_includes middleware, "Rack::Config"
       assert_not middleware.include?("Rack::Runtime")
     end
 
@@ -161,21 +194,21 @@ module ApplicationTests
       add_to_config "config.middleware.delete Rack::Runtime"
       add_to_config "config.middleware.insert_after(Rack::Runtime, Rack::Config)"
       boot!
-      assert middleware.include?("Rack::Config")
+      assert_includes middleware, "Rack::Config"
       assert_not middleware.include?("Rack::Runtime")
     end
 
     test "includes exceptions middlewares even if action_dispatch.show_exceptions is disabled" do
       add_to_config "config.action_dispatch.show_exceptions = false"
       boot!
-      assert middleware.include?("ActionDispatch::ShowExceptions")
-      assert middleware.include?("ActionDispatch::DebugExceptions")
+      assert_includes middleware, "ActionDispatch::ShowExceptions"
+      assert_includes middleware, "ActionDispatch::DebugExceptions"
     end
 
     test "removes ActionDispatch::Reloader if cache_classes is true" do
       add_to_config "config.cache_classes = true"
       boot!
-      assert !middleware.include?("ActionDispatch::Reloader")
+      assert_not_includes middleware, "ActionDispatch::Reloader"
     end
 
     test "use middleware" do
@@ -191,10 +224,10 @@ module ApplicationTests
       assert_equal "Rack::Config", middleware.second
     end
 
-    test 'unshift middleware' do
-      add_to_config 'config.middleware.unshift Rack::Config'
+    test "unshift middleware" do
+      add_to_config "config.middleware.unshift Rack::Config"
       boot!
-      assert_equal 'Rack::Config', middleware.first
+      assert_equal "Rack::Config", middleware.first
     end
 
     test "Rails.cache does not respond to middleware" do
@@ -216,7 +249,7 @@ module ApplicationTests
 
     test "can't change middleware after it's built" do
       boot!
-      assert_raise RuntimeError do
+      assert_raise frozen_error_class do
         app.config.middleware.use Rack::Config
       end
     end
@@ -228,9 +261,9 @@ module ApplicationTests
       class ::OmgController < ActionController::Base
         def index
           if params[:nothing]
-            render text: ""
+            render plain: ""
           else
-            render text: "OMG"
+            render plain: "OMG"
           end
         end
       end
@@ -240,23 +273,23 @@ module ApplicationTests
       get "/"
       assert_equal 200, last_response.status
       assert_equal "OMG", last_response.body
-      assert_equal "text/html; charset=utf-8", last_response.headers["Content-Type"]
+      assert_equal "text/plain; charset=utf-8", last_response.headers["Content-Type"]
       assert_equal "max-age=0, private, must-revalidate", last_response.headers["Cache-Control"]
       assert_equal etag, last_response.headers["Etag"]
 
-      get "/", {}, "HTTP_IF_NONE_MATCH" => etag
+      get "/", {}, { "HTTP_IF_NONE_MATCH" => etag }
       assert_equal 304, last_response.status
       assert_equal "", last_response.body
-      assert_equal nil, last_response.headers["Content-Type"]
+      assert_nil last_response.headers["Content-Type"]
       assert_equal "max-age=0, private, must-revalidate", last_response.headers["Cache-Control"]
       assert_equal etag, last_response.headers["Etag"]
 
       get "/?nothing=true"
       assert_equal 200, last_response.status
       assert_equal "", last_response.body
-      assert_equal "text/html; charset=utf-8", last_response.headers["Content-Type"]
+      assert_equal "text/plain; charset=utf-8", last_response.headers["Content-Type"]
       assert_equal "no-cache", last_response.headers["Cache-Control"]
-      assert_equal nil, last_response.headers["Etag"]
+      assert_nil last_response.headers["Etag"]
     end
 
     test "ORIGINAL_FULLPATH is passed to env" do
diff --git a/railties/test/application/multiple_applications_test.rb b/railties/test/application/multiple_applications_test.rb
index f2770a9cb4..d6c81c1fe2 100644
--- a/railties/test/application/multiple_applications_test.rb
+++ b/railties/test/application/multiple_applications_test.rb
@@ -1,4 +1,6 @@
-require 'isolation/abstract_unit'
+# frozen_string_literal: true
+
+require "isolation/abstract_unit"
 
 module ApplicationTests
   class MultipleApplicationsTest < ActiveSupport::TestCase
@@ -6,9 +8,8 @@ module ApplicationTests
 
     def setup
       build_app(initializers: true)
-      boot_rails
       require "#{rails_root}/config/environment"
-      Rails.application.config.some_setting = 'something_or_other'
+      Rails.application.config.some_setting = "something_or_other"
     end
 
     def teardown
@@ -88,9 +89,9 @@ module ApplicationTests
       require "#{app_path}/config/environment"
 
       assert_equal 0, run_count, "The count should stay at zero without any calls to the rake tasks"
-      require 'rake'
-      require 'rake/testtask'
-      require 'rdoc/task'
+      require "rake"
+      require "rake/testtask"
+      require "rdoc/task"
       Rails.application.load_tasks
       assert_equal 2, run_count, "Calling a rake task should result in two increments to the count"
     end
diff --git a/railties/test/application/paths_test.rb b/railties/test/application/paths_test.rb
index 4029984ce9..0abc5cc9aa 100644
--- a/railties/test/application/paths_test.rb
+++ b/railties/test/application/paths_test.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require "isolation/abstract_unit"
 
 module ApplicationTests
@@ -6,7 +8,6 @@ module ApplicationTests
 
     def setup
       build_app
-      boot_rails
       FileUtils.rm_rf("#{app_path}/config/environments")
       app_file "config/environments/development.rb", ""
       add_to_config <<-RUBY
@@ -56,9 +57,9 @@ module ApplicationTests
 
     test "booting up Rails yields a list of paths that are eager" do
       eager_load = @paths.eager_load
-      assert eager_load.include?(root("app/controllers"))
-      assert eager_load.include?(root("app/helpers"))
-      assert eager_load.include?(root("app/models"))
+      assert_includes eager_load, root("app/controllers")
+      assert_includes eager_load, root("app/helpers")
+      assert_includes eager_load, root("app/models")
     end
 
     test "environments has a glob equal to the current environment" do
diff --git a/railties/test/application/per_request_digest_cache_test.rb b/railties/test/application/per_request_digest_cache_test.rb
index dfe3fc9354..e9bc91785c 100644
--- a/railties/test/application/per_request_digest_cache_test.rb
+++ b/railties/test/application/per_request_digest_cache_test.rb
@@ -1,9 +1,11 @@
-require 'isolation/abstract_unit'
-require 'rack/test'
-require 'minitest/mock'
+# frozen_string_literal: true
 
-require 'action_view'
-require 'active_support/testing/method_call_assertions'
+require "isolation/abstract_unit"
+require "rack/test"
+require "minitest/mock"
+
+require "action_view"
+require "active_support/testing/method_call_assertions"
 
 class PerRequestDigestCacheTest < ActiveSupport::TestCase
   include ActiveSupport::Testing::Isolation
@@ -12,22 +14,26 @@ class PerRequestDigestCacheTest < ActiveSupport::TestCase
 
   setup do
     build_app
-    add_to_config 'config.consider_all_requests_local = true'
+    add_to_config "config.consider_all_requests_local = true"
 
-    app_file 'app/models/customer.rb', <<-RUBY
+    app_file "app/models/customer.rb", <<-RUBY
       class Customer < Struct.new(:name, :id)
         extend ActiveModel::Naming
         include ActiveModel::Conversion
+
+        def cache_key
+          [ name, id ].join("/")
+        end
       end
     RUBY
 
-    app_file 'config/routes.rb', <<-RUBY
+    app_file "config/routes.rb", <<-RUBY
       Rails.application.routes.draw do
         resources :customers, only: :index
       end
     RUBY
 
-    app_file 'app/controllers/customers_controller.rb', <<-RUBY
+    app_file "app/controllers/customers_controller.rb", <<-RUBY
       class CustomersController < ApplicationController
         self.perform_caching = true
 
@@ -37,7 +43,7 @@ class PerRequestDigestCacheTest < ActiveSupport::TestCase
       end
     RUBY
 
-    app_file 'app/views/customers/_customer.html.erb', <<-RUBY
+    app_file "app/views/customers/_customer.html.erb", <<-RUBY
       <% cache customer do %>
         <%= customer.name %>
       <% end %>
@@ -49,17 +55,17 @@ class PerRequestDigestCacheTest < ActiveSupport::TestCase
   teardown :teardown_app
 
   test "digests are reused when rendering the same template twice" do
-    get '/customers'
+    get "/customers"
     assert_equal 200, last_response.status
 
     values = ActionView::LookupContext::DetailsKey.digest_caches.first.values
-    assert_equal [ '8ba099b7749542fe765ff34a6824d548' ], values
+    assert_equal [ "8ba099b7749542fe765ff34a6824d548" ], values
     assert_equal %w(david dingus), last_response.body.split.map(&:strip)
   end
 
   test "template digests are cleared before a request" do
     assert_called(ActionView::LookupContext::DetailsKey, :clear) do
-      get '/customers'
+      get "/customers"
       assert_equal 200, last_response.status
     end
   end
diff --git a/railties/test/application/rack/logger_test.rb b/railties/test/application/rack/logger_test.rb
index 0082ec9cd2..d949a48366 100644
--- a/railties/test/application/rack/logger_test.rb
+++ b/railties/test/application/rack/logger_test.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require "isolation/abstract_unit"
 require "active_support/log_subscriber/test_helper"
 require "rack/test"
@@ -41,13 +43,13 @@ module ApplicationTests
       end
 
       test "logger logs HTTP verb override" do
-        post "/", _method: 'put'
+        post "/", _method: "put"
         wait
         assert_match 'Started PUT "/"', logs
       end
 
       test "logger logs HEAD requests" do
-        post "/", _method: 'head'
+        post "/", _method: "head"
         wait
         assert_match 'Started HEAD "/"', logs
       end
diff --git a/railties/test/application/rackup_test.rb b/railties/test/application/rackup_test.rb
index 49ac9fc66c..383f18a7da 100644
--- a/railties/test/application/rackup_test.rb
+++ b/railties/test/application/rackup_test.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require "isolation/abstract_unit"
 
 module ApplicationTests
@@ -12,14 +14,13 @@ module ApplicationTests
 
     def setup
       build_app
-      boot_rails
     end
 
     def teardown
       teardown_app
     end
 
-    test "rails app is present" do
+    test "Rails app is present" do
       assert File.exist?(app_path("config"))
     end
 
@@ -37,7 +38,7 @@ module ApplicationTests
 
     test "the config object is available on the application object" do
       rackup
-      assert_equal 'UTC', Rails.application.config.time_zone
+      assert_equal "UTC", Rails.application.config.time_zone
     end
   end
 end
diff --git a/railties/test/application/rake/dbs_test.rb b/railties/test/application/rake/dbs_test.rb
index cee9db5535..5b4c42c189 100644
--- a/railties/test/application/rake/dbs_test.rb
+++ b/railties/test/application/rake/dbs_test.rb
@@ -1,5 +1,6 @@
+# frozen_string_literal: true
+
 require "isolation/abstract_unit"
-require "active_support/core_ext/string/strip"
 
 module ApplicationTests
   module RakeTests
@@ -8,7 +9,6 @@ module ApplicationTests
 
       def setup
         build_app
-        boot_rails
         FileUtils.rm_rf("#{app_path}/config/environments")
       end
 
@@ -21,48 +21,63 @@ module ApplicationTests
       end
 
       def set_database_url
-        ENV['DATABASE_URL'] = "sqlite3:#{database_url_db_name}"
+        ENV["DATABASE_URL"] = "sqlite3:#{database_url_db_name}"
         # ensure it's using the DATABASE_URL
         FileUtils.rm_rf("#{app_path}/config/database.yml")
       end
 
-      def db_create_and_drop(expected_database)
+      def db_create_and_drop(expected_database, environment_loaded: true)
         Dir.chdir(app_path) do
-          output = `bin/rails db:create`
+          output = rails("db:create")
           assert_match(/Created database/, output)
           assert File.exist?(expected_database)
-          assert_equal expected_database, ActiveRecord::Base.connection_config[:database]
-          output = `bin/rails db:drop`
+          assert_equal expected_database, ActiveRecord::Base.connection_config[:database] if environment_loaded
+          output = rails("db:drop")
           assert_match(/Dropped database/, output)
           assert !File.exist?(expected_database)
         end
       end
 
-      test 'db:create and db:drop without database url' do
+      test "db:create and db:drop without database url" do
         require "#{app_path}/config/environment"
-        db_create_and_drop ActiveRecord::Base.configurations[Rails.env]['database']
+        db_create_and_drop ActiveRecord::Base.configurations[Rails.env]["database"]
       end
 
-      test 'db:create and db:drop with database url' do
+      test "db:create and db:drop with database url" do
         require "#{app_path}/config/environment"
         set_database_url
         db_create_and_drop database_url_db_name
       end
 
+      test "db:create and db:drop respect environment setting" do
+        app_file "config/database.yml", <<-YAML
+          development:
+            database: <%= Rails.application.config.database %>
+            adapter: sqlite3
+        YAML
+
+        app_file "config/environments/development.rb", <<-RUBY
+          Rails.application.configure do
+            config.database = "db/development.sqlite3"
+          end
+        RUBY
+
+        db_create_and_drop "db/development.sqlite3", environment_loaded: false
+      end
+
       def with_database_existing
         Dir.chdir(app_path) do
           set_database_url
-          `bin/rails db:create`
+          rails "db:create"
           yield
-          `bin/rails db:drop`
+          rails "db:drop"
         end
       end
 
-      test 'db:create failure because database exists' do
+      test "db:create failure because database exists" do
         with_database_existing do
-          output = `bin/rails db:create 2>&1`
+          output = rails("db:create")
           assert_match(/already exists/, output)
-          assert_equal 0, $?.exitstatus
         end
       end
 
@@ -75,26 +90,37 @@ module ApplicationTests
         end
       end
 
-      test 'db:create failure because bad permissions' do
+      test "db:create failure because bad permissions" do
         with_bad_permissions do
-          output = `bin/rails db:create 2>&1`
+          output = rails("db:create", allow_failure: true)
           assert_match(/Couldn't create database/, output)
           assert_equal 1, $?.exitstatus
         end
       end
 
-      test 'db:drop failure because database does not exist' do
-        Dir.chdir(app_path) do
-          output = `bin/rails db:drop:_unsafe --trace 2>&1`
-          assert_match(/does not exist/, output)
+      test "db:create works when schema cache exists and database does not exist" do
+        use_postgresql
+
+        begin
+          rails %w(db:create db:migrate db:schema:cache:dump)
+
+          rails "db:drop"
+          rails "db:create"
           assert_equal 0, $?.exitstatus
+        ensure
+          rails "db:drop" rescue nil
         end
       end
 
-      test 'db:drop failure because bad permissions' do
+      test "db:drop failure because database does not exist" do
+        output = rails("db:drop:_unsafe", "--trace")
+        assert_match(/does not exist/, output)
+      end
+
+      test "db:drop failure because bad permissions" do
         with_database_existing do
           with_bad_permissions do
-            output = `bin/rails db:drop 2>&1`
+            output = rails("db:drop", allow_failure: true)
             assert_match(/Couldn't drop/, output)
             assert_equal 1, $?.exitstatus
           end
@@ -102,21 +128,19 @@ module ApplicationTests
       end
 
       def db_migrate_and_status(expected_database)
-        Dir.chdir(app_path) do
-          `bin/rails generate model book title:string;
-           bin/rails db:migrate`
-          output = `bin/rails db:migrate:status`
-          assert_match(%r{database:\s+\S*#{Regexp.escape(expected_database)}}, output)
-          assert_match(/up\s+\d{14}\s+Create books/, output)
-        end
+        rails "generate", "model", "book", "title:string"
+        rails "db:migrate"
+        output = rails("db:migrate:status")
+        assert_match(%r{database:\s+\S*#{Regexp.escape(expected_database)}}, output)
+        assert_match(/up\s+\d{14}\s+Create books/, output)
       end
 
-      test 'db:migrate and db:migrate:status without database_url' do
+      test "db:migrate and db:migrate:status without database_url" do
         require "#{app_path}/config/environment"
-        db_migrate_and_status ActiveRecord::Base.configurations[Rails.env]['database']
+        db_migrate_and_status ActiveRecord::Base.configurations[Rails.env]["database"]
       end
 
-      test 'db:migrate and db:migrate:status with database_url' do
+      test "db:migrate and db:migrate:status with database_url" do
         require "#{app_path}/config/environment"
         set_database_url
         db_migrate_and_status database_url_db_name
@@ -124,170 +148,176 @@ module ApplicationTests
 
       def db_schema_dump
         Dir.chdir(app_path) do
-          `bin/rails generate model book title:string;
-           bin/rails db:migrate db:schema:dump`
+          rails "generate", "model", "book", "title:string"
+          rails "db:migrate", "db:schema:dump"
           schema_dump = File.read("db/schema.rb")
           assert_match(/create_table \"books\"/, schema_dump)
         end
       end
 
-      test 'db:schema:dump without database_url' do
+      test "db:schema:dump without database_url" do
         db_schema_dump
       end
 
-      test 'db:schema:dump with database_url' do
+      test "db:schema:dump with database_url" do
         set_database_url
         db_schema_dump
       end
 
       def db_fixtures_load(expected_database)
         Dir.chdir(app_path) do
-          `bin/rails generate model book title:string;
-           bin/rails db:migrate db:fixtures:load`
+          rails "generate", "model", "book", "title:string"
+          rails "db:migrate", "db:fixtures:load"
           assert_match expected_database, ActiveRecord::Base.connection_config[:database]
           require "#{app_path}/app/models/book"
           assert_equal 2, Book.count
         end
       end
 
-      test 'db:fixtures:load without database_url' do
+      test "db:fixtures:load without database_url" do
         require "#{app_path}/config/environment"
-        db_fixtures_load ActiveRecord::Base.configurations[Rails.env]['database']
+        db_fixtures_load ActiveRecord::Base.configurations[Rails.env]["database"]
       end
 
-      test 'db:fixtures:load with database_url' do
+      test "db:fixtures:load with database_url" do
         require "#{app_path}/config/environment"
         set_database_url
         db_fixtures_load database_url_db_name
       end
 
-      test 'db:fixtures:load with namespaced fixture' do
+      test "db:fixtures:load with namespaced fixture" do
         require "#{app_path}/config/environment"
-        Dir.chdir(app_path) do
-          `bin/rails generate model admin::book title:string;
-           bin/rails db:migrate db:fixtures:load`
-          require "#{app_path}/app/models/admin/book"
-          assert_equal 2, Admin::Book.count
-        end
+
+        rails "generate", "model", "admin::book", "title:string"
+        rails "db:migrate", "db:fixtures:load"
+        require "#{app_path}/app/models/admin/book"
+        assert_equal 2, Admin::Book.count
       end
 
       def db_structure_dump_and_load(expected_database)
         Dir.chdir(app_path) do
-          `bin/rails generate model book title:string;
-           bin/rails db:migrate db:structure:dump`
+          rails "generate", "model", "book", "title:string"
+          rails "db:migrate", "db:structure:dump"
           structure_dump = File.read("db/structure.sql")
-          assert_match(/CREATE TABLE \"books\"/, structure_dump)
-          `bin/rails environment db:drop db:structure:load`
+          assert_match(/CREATE TABLE (?:IF NOT EXISTS )?\"books\"/, structure_dump)
+          rails "environment", "db:drop", "db:structure:load"
           assert_match expected_database, ActiveRecord::Base.connection_config[:database]
           require "#{app_path}/app/models/book"
-          #if structure is not loaded correctly, exception would be raised
+          # if structure is not loaded correctly, exception would be raised
           assert_equal 0, Book.count
         end
       end
 
-      test 'db:structure:dump and db:structure:load without database_url' do
+      test "db:structure:dump and db:structure:load without database_url" do
         require "#{app_path}/config/environment"
-        db_structure_dump_and_load ActiveRecord::Base.configurations[Rails.env]['database']
+        db_structure_dump_and_load ActiveRecord::Base.configurations[Rails.env]["database"]
       end
 
-      test 'db:structure:dump and db:structure:load with database_url' do
+      test "db:structure:dump and db:structure:load with database_url" do
         require "#{app_path}/config/environment"
         set_database_url
         db_structure_dump_and_load database_url_db_name
       end
 
-      test 'db:structure:dump does not dump schema information when no migrations are used' do
-        Dir.chdir(app_path) do
-          # create table without migrations
-          `bin/rails runner 'ActiveRecord::Base.connection.create_table(:posts) {|t| t.string :title }'`
+      test "db:structure:dump and db:structure:load set ar_internal_metadata" do
+        require "#{app_path}/config/environment"
+        db_structure_dump_and_load ActiveRecord::Base.configurations[Rails.env]["database"]
 
-          stderr_output = capture(:stderr) { `bin/rails db:structure:dump` }
-          assert_empty stderr_output
-          structure_dump = File.read("db/structure.sql")
-          assert_match(/CREATE TABLE \"posts\"/, structure_dump)
-        end
+        assert_equal "test", rails("runner", "-e", "test", "puts ActiveRecord::InternalMetadata[:environment]").strip
+        assert_equal "development", rails("runner", "puts ActiveRecord::InternalMetadata[:environment]").strip
       end
 
-      test 'db:schema:load and db:structure:load do not purge the existing database' do
-        Dir.chdir(app_path) do
-          `bin/rails runner 'ActiveRecord::Base.connection.create_table(:posts) {|t| t.string :title }'`
+      test "db:structure:dump does not dump schema information when no migrations are used" do
+        # create table without migrations
+        rails "runner", "ActiveRecord::Base.connection.create_table(:posts) {|t| t.string :title }"
 
-          app_file 'db/schema.rb', <<-RUBY
-            ActiveRecord::Schema.define(version: 20140423102712) do
-              create_table(:comments) {}
-            end
-          RUBY
+        stderr_output = capture(:stderr) { rails("db:structure:dump", stderr: true, allow_failure: true) }
+        assert_empty stderr_output
+        structure_dump = File.read("#{app_path}/db/structure.sql")
+        assert_match(/CREATE TABLE (?:IF NOT EXISTS )?\"posts\"/, structure_dump)
+      end
 
-          list_tables = lambda { `bin/rails runner 'p ActiveRecord::Base.connection.tables'`.strip }
+      test "db:schema:load and db:structure:load do not purge the existing database" do
+        rails "runner", "ActiveRecord::Base.connection.create_table(:posts) {|t| t.string :title }"
 
-          assert_equal '["posts"]', list_tables[]
-          `bin/rails db:schema:load`
-          assert_equal '["posts", "comments", "schema_migrations", "ar_internal_metadata"]', list_tables[]
+        app_file "db/schema.rb", <<-RUBY
+          ActiveRecord::Schema.define(version: 20140423102712) do
+            create_table(:comments) {}
+          end
+        RUBY
 
-          app_file 'db/structure.sql', <<-SQL
-            CREATE TABLE "users" ("id" INTEGER PRIMARY KEY AUTOINCREMENT NOT NULL, "name" varchar(255));
-          SQL
+        list_tables = lambda { rails("runner", "p ActiveRecord::Base.connection.tables").strip }
 
-          `bin/rails db:structure:load`
-          assert_equal '["posts", "comments", "schema_migrations", "ar_internal_metadata", "users"]', list_tables[]
-        end
+        assert_equal '["posts"]', list_tables[]
+        rails "db:schema:load"
+        assert_equal '["posts", "comments", "schema_migrations", "ar_internal_metadata"]', list_tables[]
+
+        app_file "db/structure.sql", <<-SQL
+          CREATE TABLE "users" ("id" INTEGER PRIMARY KEY AUTOINCREMENT NOT NULL, "name" varchar(255));
+        SQL
+
+        rails "db:structure:load"
+        assert_equal '["posts", "comments", "schema_migrations", "ar_internal_metadata", "users"]', list_tables[]
       end
 
       test "db:schema:load with inflections" do
-        Dir.chdir(app_path) do
-          app_file 'config/initializers/inflection.rb', <<-RUBY
-            ActiveSupport::Inflector.inflections do |inflect|
-              inflect.irregular 'goose', 'geese'
-            end
-          RUBY
-          app_file 'config/initializers/primary_key_table_name.rb', <<-RUBY
-            ActiveRecord::Base.primary_key_prefix_type = :table_name
-          RUBY
-          app_file 'db/schema.rb', <<-RUBY
-            ActiveRecord::Schema.define(version: 20140423102712) do
-              create_table("goose".pluralize) do |t|
-                t.string :name
-              end
+        app_file "config/initializers/inflection.rb", <<-RUBY
+          ActiveSupport::Inflector.inflections do |inflect|
+            inflect.irregular 'goose', 'geese'
+          end
+        RUBY
+        app_file "config/initializers/primary_key_table_name.rb", <<-RUBY
+          ActiveRecord::Base.primary_key_prefix_type = :table_name
+        RUBY
+        app_file "db/schema.rb", <<-RUBY
+          ActiveRecord::Schema.define(version: 20140423102712) do
+            create_table("goose".pluralize) do |t|
+              t.string :name
             end
-          RUBY
+          end
+        RUBY
 
-          `bin/rails db:schema:load`
+        rails "db:schema:load"
 
-          tables = `bin/rails runner 'p ActiveRecord::Base.connection.tables'`.strip
-          assert_match(/"geese"/, tables)
+        tables = rails("runner", "p ActiveRecord::Base.connection.tables").strip
+        assert_match(/"geese"/, tables)
 
-          columns = `bin/rails runner 'p ActiveRecord::Base.connection.columns("geese").map(&:name)'`.strip
-          assert_equal columns, '["gooseid", "name"]'
-        end
+        columns = rails("runner", "p ActiveRecord::Base.connection.columns('geese').map(&:name)").strip
+        assert_equal columns, '["gooseid", "name"]'
+      end
+
+      test "db:schema:load fails if schema.rb doesn't exist yet" do
+        stderr_output = capture(:stderr) { rails("db:schema:load", stderr: true, allow_failure: true) }
+        assert_match(/Run `rails db:migrate` to create it/, stderr_output)
       end
 
       def db_test_load_structure
         Dir.chdir(app_path) do
-          `bin/rails generate model book title:string;
-           bin/rails db:migrate db:structure:dump db:test:load_structure`
+          rails "generate", "model", "book", "title:string"
+          rails "db:migrate", "db:structure:dump", "db:test:load_structure"
           ActiveRecord::Base.configurations = Rails.application.config.database_configuration
           ActiveRecord::Base.establish_connection :test
           require "#{app_path}/app/models/book"
-          #if structure is not loaded correctly, exception would be raised
+          # if structure is not loaded correctly, exception would be raised
           assert_equal 0, Book.count
-          assert_match ActiveRecord::Base.configurations['test']['database'],
+          assert_match ActiveRecord::Base.configurations["test"]["database"],
             ActiveRecord::Base.connection_config[:database]
         end
       end
 
-      test 'db:test:load_structure without database_url' do
+      test "db:test:load_structure without database_url" do
         require "#{app_path}/config/environment"
         db_test_load_structure
       end
 
-      test 'db:setup loads schema and seeds database' do
+      test "db:setup loads schema and seeds database" do
         begin
           @old_rails_env = ENV["RAILS_ENV"]
           @old_rack_env = ENV["RACK_ENV"]
           ENV.delete "RAILS_ENV"
           ENV.delete "RACK_ENV"
 
-          app_file 'db/schema.rb', <<-RUBY
+          app_file "db/schema.rb", <<-RUBY
             ActiveRecord::Schema.define(version: "1") do
               create_table :users do |t|
                 t.string :name
@@ -295,19 +325,56 @@ module ApplicationTests
             end
           RUBY
 
-          app_file 'db/seeds.rb', <<-RUBY
+          app_file "db/seeds.rb", <<-RUBY
             puts ActiveRecord::Base.connection_config[:database]
           RUBY
 
-          Dir.chdir(app_path) do
-            database_path = `bin/rails db:setup`
-            assert_equal "development.sqlite3", File.basename(database_path.strip)
-          end
+          database_path = rails("db:setup")
+          assert_equal "development.sqlite3", File.basename(database_path.strip)
         ensure
           ENV["RAILS_ENV"] = @old_rails_env
           ENV["RACK_ENV"] = @old_rack_env
         end
       end
+
+      test "db:setup sets ar_internal_metadata" do
+        app_file "db/schema.rb", ""
+        rails "db:setup"
+
+        test_environment = lambda { rails("runner", "-e", "test", "puts ActiveRecord::InternalMetadata[:environment]").strip }
+        development_environment = lambda { rails("runner", "puts ActiveRecord::InternalMetadata[:environment]").strip }
+
+        assert_equal "test", test_environment.call
+        assert_equal "development", development_environment.call
+
+        app_file "db/structure.sql", ""
+        app_file "config/initializers/enable_sql_schema_format.rb", <<-RUBY
+          Rails.application.config.active_record.schema_format = :sql
+        RUBY
+
+        rails "db:setup"
+
+        assert_equal "test", test_environment.call
+        assert_equal "development", development_environment.call
+      end
+
+      test "db:test:prepare sets test ar_internal_metadata" do
+        app_file "db/schema.rb", ""
+        rails "db:test:prepare"
+
+        test_environment = lambda { rails("runner", "-e", "test", "puts ActiveRecord::InternalMetadata[:environment]").strip }
+
+        assert_equal "test", test_environment.call
+
+        app_file "db/structure.sql", ""
+        app_file "config/initializers/enable_sql_schema_format.rb", <<-RUBY
+          Rails.application.config.active_record.schema_format = :sql
+        RUBY
+
+        rails "db:test:prepare"
+
+        assert_equal "test", test_environment.call
+      end
     end
   end
 end
diff --git a/railties/test/application/rake/dev_test.rb b/railties/test/application/rake/dev_test.rb
index 2330ad3535..66e1ac9d99 100644
--- a/railties/test/application/rake/dev_test.rb
+++ b/railties/test/application/rake/dev_test.rb
@@ -1,4 +1,6 @@
-require 'isolation/abstract_unit'
+# frozen_string_literal: true
+
+require "isolation/abstract_unit"
 
 module ApplicationTests
   module RakeTests
@@ -13,29 +15,33 @@ module ApplicationTests
         teardown_app
       end
 
-      test 'dev:cache creates file and outputs message' do
+      test "dev:cache creates file and outputs message" do
         Dir.chdir(app_path) do
-          output = `rails dev:cache`
-          assert File.exist?('tmp/caching-dev.txt')
+          output = rails("dev:cache")
+          assert File.exist?("tmp/caching-dev.txt")
           assert_match(/Development mode is now being cached/, output)
         end
       end
 
-      test 'dev:cache deletes file and outputs message' do
+      test "dev:cache deletes file and outputs message" do
         Dir.chdir(app_path) do
-          `rails dev:cache` # Create caching file.
-          output = `rails dev:cache` # Delete caching file.
-          assert_not File.exist?('tmp/caching-dev.txt')
+          rails "dev:cache" # Create caching file.
+          output = rails("dev:cache") # Delete caching file.
+          assert_not File.exist?("tmp/caching-dev.txt")
           assert_match(/Development mode is no longer being cached/, output)
         end
       end
 
-      test 'dev:cache removes server.pid also' do
+      test "dev:cache touches tmp/restart.txt" do
         Dir.chdir(app_path) do
-          FileUtils.mkdir_p("tmp/pids")
-          FileUtils.touch("tmp/pids/server.pid")
-          `rails dev:cache`
-          assert_not File.exist?("tmp/pids/server.pid")
+          rails "dev:cache"
+          assert File.exist?("tmp/restart.txt")
+
+          prev_mtime = File.mtime("tmp/restart.txt")
+          sleep(1)
+          rails "dev:cache"
+          curr_mtime = File.mtime("tmp/restart.txt")
+          assert_not_equal prev_mtime, curr_mtime
         end
       end
     end
diff --git a/railties/test/application/rake/framework_test.rb b/railties/test/application/rake/framework_test.rb
index ec57af79f6..644b1924b5 100644
--- a/railties/test/application/rake/framework_test.rb
+++ b/railties/test/application/rake/framework_test.rb
@@ -1,5 +1,6 @@
+# frozen_string_literal: true
+
 require "isolation/abstract_unit"
-require "active_support/core_ext/string/strip"
 
 module ApplicationTests
   module RakeTests
@@ -8,7 +9,6 @@ module ApplicationTests
 
       def setup
         build_app
-        boot_rails
         FileUtils.rm_rf("#{app_path}/config/environments")
       end
 
@@ -17,14 +17,14 @@ module ApplicationTests
       end
 
       def load_tasks
-        require 'rake'
-        require 'rdoc/task'
-        require 'rake/testtask'
+        require "rake"
+        require "rdoc/task"
+        require "rake/testtask"
 
         Rails.application.load_tasks
       end
 
-      test 'requiring the rake task should not define method .app_generator on Object' do
+      test "requiring the rake task should not define method .app_generator on Object" do
         require "#{app_path}/config/environment"
 
         load_tasks
@@ -34,7 +34,7 @@ module ApplicationTests
         end
       end
 
-      test 'requiring the rake task should not define method .invoke_from_app_generator on Object' do
+      test "requiring the rake task should not define method .invoke_from_app_generator on Object" do
         require "#{app_path}/config/environment"
 
         load_tasks
diff --git a/railties/test/application/rake/log_test.rb b/railties/test/application/rake/log_test.rb
new file mode 100644
index 0000000000..678f26db26
--- /dev/null
+++ b/railties/test/application/rake/log_test.rb
@@ -0,0 +1,35 @@
+# frozen_string_literal: true
+
+require "isolation/abstract_unit"
+
+module ApplicationTests
+  module RakeTests
+    class LogTest < ActiveSupport::TestCase
+      include ActiveSupport::Testing::Isolation
+
+      def setup
+        build_app
+      end
+
+      def teardown
+        teardown_app
+      end
+
+      test "log:clear clear all environments log files by default" do
+        Dir.chdir(app_path) do
+          File.open("config/environments/staging.rb", "w")
+
+          File.write("log/staging.log", "staging")
+          File.write("log/test.log", "test")
+          File.write("log/dummy.log", "dummy")
+
+          rails "log:clear"
+
+          assert_equal 0, File.size("log/test.log")
+          assert_equal 0, File.size("log/staging.log")
+          assert_equal 5, File.size("log/dummy.log")
+        end
+      end
+    end
+  end
+end
diff --git a/railties/test/application/rake/migrations_test.rb b/railties/test/application/rake/migrations_test.rb
index 7e2519ae5a..788f9160d6 100644
--- a/railties/test/application/rake/migrations_test.rb
+++ b/railties/test/application/rake/migrations_test.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require "isolation/abstract_unit"
 
 module ApplicationTests
@@ -5,7 +7,6 @@ module ApplicationTests
     class RakeMigrationsTest < ActiveSupport::TestCase
       def setup
         build_app
-        boot_rails
         FileUtils.rm_rf("#{app_path}/config/environments")
       end
 
@@ -13,211 +14,421 @@ module ApplicationTests
         teardown_app
       end
 
-      test 'running migrations with given scope' do
-        Dir.chdir(app_path) do
-          `bin/rails generate model user username:string password:string`
+      test "running migrations with given scope" do
+        rails "generate", "model", "user", "username:string", "password:string"
 
-          app_file "db/migrate/01_a_migration.bukkits.rb", <<-MIGRATION
-            class AMigration < ActiveRecord::Migration::Current
-            end
-          MIGRATION
+        app_file "db/migrate/01_a_migration.bukkits.rb", <<-MIGRATION
+          class AMigration < ActiveRecord::Migration::Current
+          end
+        MIGRATION
 
-          output = `bin/rails db:migrate SCOPE=bukkits`
-          assert_no_match(/create_table\(:users\)/, output)
-          assert_no_match(/CreateUsers/, output)
-          assert_no_match(/add_column\(:users, :email, :string\)/, output)
+        output = rails("db:migrate", "SCOPE=bukkits")
+        assert_no_match(/create_table\(:users\)/, output)
+        assert_no_match(/CreateUsers/, output)
+        assert_no_match(/add_column\(:users, :email, :string\)/, output)
 
-          assert_match(/AMigration: migrated/, output)
+        assert_match(/AMigration: migrated/, output)
 
-          output = `bin/rails db:migrate SCOPE=bukkits VERSION=0`
-          assert_no_match(/drop_table\(:users\)/, output)
-          assert_no_match(/CreateUsers/, output)
-          assert_no_match(/remove_column\(:users, :email\)/, output)
+        output = rails("db:migrate", "SCOPE=bukkits", "VERSION=0")
+        assert_no_match(/drop_table\(:users\)/, output)
+        assert_no_match(/CreateUsers/, output)
+        assert_no_match(/remove_column\(:users, :email\)/, output)
 
-          assert_match(/AMigration: reverted/, output)
-        end
+        assert_match(/AMigration: reverted/, output)
       end
 
-      test 'model and migration generator with change syntax' do
-        Dir.chdir(app_path) do
-          `bin/rails generate model user username:string password:string;
-           bin/rails generate migration add_email_to_users email:string`
-
-           output = `bin/rails db:migrate`
-           assert_match(/create_table\(:users\)/, output)
-           assert_match(/CreateUsers: migrated/, output)
-           assert_match(/add_column\(:users, :email, :string\)/, output)
-           assert_match(/AddEmailToUsers: migrated/, output)
-
-           output = `bin/rails db:rollback STEP=2`
-           assert_match(/drop_table\(:users\)/, output)
-           assert_match(/CreateUsers: reverted/, output)
-           assert_match(/remove_column\(:users, :email, :string\)/, output)
-           assert_match(/AddEmailToUsers: reverted/, output)
-        end
+      test "migrate with specified VERSION in different formats" do
+        app_file "db/migrate/01_one_migration.rb", <<-MIGRATION
+          class OneMigration < ActiveRecord::Migration::Current
+          end
+        MIGRATION
+
+        app_file "db/migrate/02_two_migration.rb", <<-MIGRATION
+          class TwoMigration < ActiveRecord::Migration::Current
+          end
+        MIGRATION
+
+        app_file "db/migrate/03_three_migration.rb", <<-MIGRATION
+          class ThreeMigration < ActiveRecord::Migration::Current
+          end
+        MIGRATION
+
+        rails "db:migrate"
+
+        output = rails("db:migrate:status")
+        assert_match(/up\s+001\s+One migration/, output)
+        assert_match(/up\s+002\s+Two migration/, output)
+        assert_match(/up\s+003\s+Three migration/, output)
+
+        rails "db:migrate", "VERSION=01_one_migration.rb"
+        output = rails("db:migrate:status")
+        assert_match(/up\s+001\s+One migration/, output)
+        assert_match(/down\s+002\s+Two migration/, output)
+        assert_match(/down\s+003\s+Three migration/, output)
+
+        rails "db:migrate", "VERSION=3"
+        output = rails("db:migrate:status")
+        assert_match(/up\s+001\s+One migration/, output)
+        assert_match(/up\s+002\s+Two migration/, output)
+        assert_match(/up\s+003\s+Three migration/, output)
+
+        rails "db:migrate", "VERSION=001"
+        output = rails("db:migrate:status")
+        assert_match(/up\s+001\s+One migration/, output)
+        assert_match(/down\s+002\s+Two migration/, output)
+        assert_match(/down\s+003\s+Three migration/, output)
+      end
+
+      test "migration with empty version" do
+        app_file "db/migrate/01_one_migration.rb", <<-MIGRATION
+          class OneMigration < ActiveRecord::Migration::Current
+          end
+        MIGRATION
+
+        app_file "db/migrate/02_two_migration.rb", <<-MIGRATION
+          class TwoMigration < ActiveRecord::Migration::Current
+          end
+        MIGRATION
+
+        rails("db:migrate", "VERSION=")
+
+        output = rails("db:migrate:status")
+        assert_match(/up\s+001\s+One migration/, output)
+        assert_match(/up\s+002\s+Two migration/, output)
+
+        output = rails("db:migrate:redo", "VERSION=", allow_failure: true)
+        assert_match(/Empty VERSION provided/, output)
+
+        output = rails("db:migrate:up", "VERSION=", allow_failure: true)
+        assert_match(/VERSION is required/, output)
+
+        output = rails("db:migrate:up", allow_failure: true)
+        assert_match(/VERSION is required/, output)
+
+        output = rails("db:migrate:down", "VERSION=", allow_failure: true)
+        assert_match(/VERSION is required - To go down one migration, use db:rollback/, output)
+
+        output = rails("db:migrate:down", allow_failure: true)
+        assert_match(/VERSION is required - To go down one migration, use db:rollback/, output)
+
+        output = rails("db:migrate:status")
+        assert_match(/up\s+001\s+One migration/, output)
+        assert_match(/up\s+002\s+Two migration/, output)
+      end
+
+      test "migration with 0 version" do
+        app_file "db/migrate/01_one_migration.rb", <<-MIGRATION
+          class OneMigration < ActiveRecord::Migration::Current
+          end
+        MIGRATION
+
+        app_file "db/migrate/02_two_migration.rb", <<-MIGRATION
+          class TwoMigration < ActiveRecord::Migration::Current
+          end
+        MIGRATION
+
+        rails "db:migrate"
+
+        output = rails("db:migrate:status")
+        assert_match(/up\s+001\s+One migration/, output)
+        assert_match(/up\s+002\s+Two migration/, output)
+
+        rails "db:migrate", "VERSION=0"
+
+        output = rails("db:migrate:status")
+        assert_match(/down\s+001\s+One migration/, output)
+        assert_match(/down\s+002\s+Two migration/, output)
       end
 
-      test 'migration status when schema migrations table is not present' do
-        output = Dir.chdir(app_path){ `bin/rails db:migrate:status 2>&1` }
+      test "model and migration generator with change syntax" do
+        rails "generate", "model", "user", "username:string", "password:string"
+        rails "generate", "migration", "add_email_to_users", "email:string"
+
+        output = rails("db:migrate")
+        assert_match(/create_table\(:users\)/, output)
+        assert_match(/CreateUsers: migrated/, output)
+        assert_match(/add_column\(:users, :email, :string\)/, output)
+        assert_match(/AddEmailToUsers: migrated/, output)
+
+        output = rails("db:rollback", "STEP=2")
+        assert_match(/drop_table\(:users\)/, output)
+        assert_match(/CreateUsers: reverted/, output)
+        assert_match(/remove_column\(:users, :email, :string\)/, output)
+        assert_match(/AddEmailToUsers: reverted/, output)
+      end
+
+      test "migration status when schema migrations table is not present" do
+        output = rails("db:migrate:status", allow_failure: true)
         assert_equal "Schema migrations table does not exist yet.\n", output
       end
 
-      test 'test migration status' do
+      test "migration status" do
+        rails "generate", "model", "user", "username:string", "password:string"
+        rails "generate", "migration", "add_email_to_users", "email:string"
+        rails "db:migrate"
+
+        output = rails("db:migrate:status")
+
+        assert_match(/up\s+\d{14}\s+Create users/, output)
+        assert_match(/up\s+\d{14}\s+Add email to users/, output)
+
+        rails "db:rollback", "STEP=1"
+        output = rails("db:migrate:status")
+
+        assert_match(/up\s+\d{14}\s+Create users/, output)
+        assert_match(/down\s+\d{14}\s+Add email to users/, output)
+      end
+
+      test "migration status without timestamps" do
+        add_to_config("config.active_record.timestamped_migrations = false")
+
+        rails "generate", "model", "user", "username:string", "password:string"
+        rails "generate", "migration", "add_email_to_users", "email:string"
+        rails "db:migrate"
+
+        output = rails("db:migrate:status")
+
+        assert_match(/up\s+\d{3,}\s+Create users/, output)
+        assert_match(/up\s+\d{3,}\s+Add email to users/, output)
+
+        rails "db:rollback", "STEP=1"
+        output = rails("db:migrate:status")
+
+        assert_match(/up\s+\d{3,}\s+Create users/, output)
+        assert_match(/down\s+\d{3,}\s+Add email to users/, output)
+      end
+
+      test "migration status after rollback and redo" do
+        rails "generate", "model", "user", "username:string", "password:string"
+        rails "generate", "migration", "add_email_to_users", "email:string"
+        rails "db:migrate"
+
+        output = rails("db:migrate:status")
+
+        assert_match(/up\s+\d{14}\s+Create users/, output)
+        assert_match(/up\s+\d{14}\s+Add email to users/, output)
+
+        rails "db:rollback", "STEP=2"
+        output = rails("db:migrate:status")
+
+        assert_match(/down\s+\d{14}\s+Create users/, output)
+        assert_match(/down\s+\d{14}\s+Add email to users/, output)
+
+        rails "db:migrate:redo"
+        output = rails("db:migrate:status")
+
+        assert_match(/up\s+\d{14}\s+Create users/, output)
+        assert_match(/up\s+\d{14}\s+Add email to users/, output)
+      end
+
+      test "migration status after rollback and forward" do
+        rails "generate", "model", "user", "username:string", "password:string"
+        rails "generate", "migration", "add_email_to_users", "email:string"
+        rails "db:migrate"
+
+        output = rails("db:migrate:status")
+
+        assert_match(/up\s+\d{14}\s+Create users/, output)
+        assert_match(/up\s+\d{14}\s+Add email to users/, output)
+
+        rails "db:rollback", "STEP=2"
+        output = rails("db:migrate:status")
+
+        assert_match(/down\s+\d{14}\s+Create users/, output)
+        assert_match(/down\s+\d{14}\s+Add email to users/, output)
+
+        rails "db:forward", "STEP=2"
+        output = rails("db:migrate:status")
+
+        assert_match(/up\s+\d{14}\s+Create users/, output)
+        assert_match(/up\s+\d{14}\s+Add email to users/, output)
+      end
+
+      test "raise error on any move when current migration does not exist" do
         Dir.chdir(app_path) do
-          `bin/rails generate model user username:string password:string;
-           bin/rails generate migration add_email_to_users email:string;
-           bin/rails db:migrate`
+          rails "generate", "model", "user", "username:string", "password:string"
+          rails "generate", "migration", "add_email_to_users", "email:string"
+          rails "db:migrate"
+          `rm db/migrate/*email*.rb`
 
-          output = `bin/rails db:migrate:status`
+          output = rails("db:migrate:status")
+          assert_match(/up\s+\d{14}\s+Create users/, output)
+          assert_match(/up\s+\d{14}\s+\** NO FILE \**/, output)
+
+          output = rails("db:rollback", allow_failure: true)
+          assert_match(/rails aborted!/, output)
+          assert_match(/ActiveRecord::UnknownMigrationVersionError:/, output)
+          assert_match(/No migration with version number\s\d{14}\./, output)
 
+          output = rails("db:migrate:status")
           assert_match(/up\s+\d{14}\s+Create users/, output)
-          assert_match(/up\s+\d{14}\s+Add email to users/, output)
+          assert_match(/up\s+\d{14}\s+\** NO FILE \**/, output)
 
-          `bin/rails db:rollback STEP=1`
-          output = `bin/rails db:migrate:status`
+          output = rails("db:forward", allow_failure: true)
+          assert_match(/rails aborted!/, output)
+          assert_match(/ActiveRecord::UnknownMigrationVersionError:/, output)
+          assert_match(/No migration with version number\s\d{14}\./, output)
 
+          output = rails("db:migrate:status")
           assert_match(/up\s+\d{14}\s+Create users/, output)
-          assert_match(/down\s+\d{14}\s+Add email to users/, output)
+          assert_match(/up\s+\d{14}\s+\** NO FILE \**/, output)
         end
       end
 
-      test 'migration status without timestamps' do
-        add_to_config('config.active_record.timestamped_migrations = false')
+      test "raise error on any move when target migration does not exist" do
+        app_file "db/migrate/01_one_migration.rb", <<-MIGRATION
+          class OneMigration < ActiveRecord::Migration::Current
+          end
+        MIGRATION
 
-        Dir.chdir(app_path) do
-          `bin/rails generate model user username:string password:string;
-           bin/rails generate migration add_email_to_users email:string;
-           bin/rails db:migrate`
+        app_file "db/migrate/02_two_migration.rb", <<-MIGRATION
+          class TwoMigration < ActiveRecord::Migration::Current
+          end
+        MIGRATION
 
-          output = `bin/rails db:migrate:status`
+        rails "db:migrate"
 
-          assert_match(/up\s+\d{3,}\s+Create users/, output)
-          assert_match(/up\s+\d{3,}\s+Add email to users/, output)
+        output = rails("db:migrate:status")
+        assert_match(/up\s+001\s+One migration/, output)
+        assert_match(/up\s+002\s+Two migration/, output)
 
-          `bin/rails db:rollback STEP=1`
-          output = `bin/rails db:migrate:status`
+        output = rails("db:migrate", "VERSION=3", allow_failure: true)
+        assert_match(/rails aborted!/, output)
+        assert_match(/ActiveRecord::UnknownMigrationVersionError:/, output)
+        assert_match(/No migration with version number 3/, output)
 
-          assert_match(/up\s+\d{3,}\s+Create users/, output)
-          assert_match(/down\s+\d{3,}\s+Add email to users/, output)
-        end
+        output = rails("db:migrate:status")
+        assert_match(/up\s+001\s+One migration/, output)
+        assert_match(/up\s+002\s+Two migration/, output)
       end
 
-      test 'test migration status after rollback and redo' do
-        Dir.chdir(app_path) do
-          `bin/rails generate model user username:string password:string;
-           bin/rails generate migration add_email_to_users email:string;
-           bin/rails db:migrate`
+      test "raise error on any move when VERSION has invalid format" do
+        output = rails("db:migrate", "VERSION=unknown", allow_failure: true)
+        assert_match(/rails aborted!/, output)
+        assert_match(/Invalid format of target version/, output)
 
-           output = `bin/rails db:migrate:status`
+        output = rails("db:migrate", "VERSION=0.1.11", allow_failure: true)
+        assert_match(/rails aborted!/, output)
+        assert_match(/Invalid format of target version/, output)
 
-           assert_match(/up\s+\d{14}\s+Create users/, output)
-           assert_match(/up\s+\d{14}\s+Add email to users/, output)
+        output = rails("db:migrate", "VERSION=1.1.11", allow_failure: true)
+        assert_match(/rails aborted!/, output)
+        assert_match(/Invalid format of target version/, output)
 
-           `bin/rails db:rollback STEP=2`
-           output = `bin/rails db:migrate:status`
+        output = rails("db:migrate", "VERSION='0 '", allow_failure: true)
+        assert_match(/rails aborted!/, output)
+        assert_match(/Invalid format of target version/, output)
 
-           assert_match(/down\s+\d{14}\s+Create users/, output)
-           assert_match(/down\s+\d{14}\s+Add email to users/, output)
+        output = rails("db:migrate", "VERSION=1.", allow_failure: true)
+        assert_match(/rails aborted!/, output)
+        assert_match(/Invalid format of target version/, output)
 
-           `bin/rails db:migrate:redo`
-           output = `bin/rails db:migrate:status`
+        output = rails("db:migrate", "VERSION=1_", allow_failure: true)
+        assert_match(/rails aborted!/, output)
+        assert_match(/Invalid format of target version/, output)
 
-           assert_match(/up\s+\d{14}\s+Create users/, output)
-           assert_match(/up\s+\d{14}\s+Add email to users/, output)
-        end
+        output = rails("db:migrate", "VERSION=1_name", allow_failure: true)
+        assert_match(/rails aborted!/, output)
+        assert_match(/Invalid format of target version/, output)
+
+        output = rails("db:migrate:redo", "VERSION=unknown", allow_failure: true)
+        assert_match(/rails aborted!/, output)
+        assert_match(/Invalid format of target version/, output)
+
+        output = rails("db:migrate:up", "VERSION=unknown", allow_failure: true)
+        assert_match(/rails aborted!/, output)
+        assert_match(/Invalid format of target version/, output)
+
+        output = rails("db:migrate:down", "VERSION=unknown", allow_failure: true)
+        assert_match(/rails aborted!/, output)
+        assert_match(/Invalid format of target version/, output)
       end
 
-      test 'migration status after rollback and redo without timestamps' do
-        add_to_config('config.active_record.timestamped_migrations = false')
+      test "migration status after rollback and redo without timestamps" do
+        add_to_config("config.active_record.timestamped_migrations = false")
 
-        Dir.chdir(app_path) do
-          `bin/rails generate model user username:string password:string;
-           bin/rails generate migration add_email_to_users email:string;
-           bin/rails db:migrate`
+        rails "generate", "model", "user", "username:string", "password:string"
+        rails "generate", "migration", "add_email_to_users", "email:string"
+        rails "db:migrate"
 
-           output = `bin/rails db:migrate:status`
+        output = rails("db:migrate:status")
 
-           assert_match(/up\s+\d{3,}\s+Create users/, output)
-           assert_match(/up\s+\d{3,}\s+Add email to users/, output)
+        assert_match(/up\s+\d{3,}\s+Create users/, output)
+        assert_match(/up\s+\d{3,}\s+Add email to users/, output)
 
-           `bin/rails db:rollback STEP=2`
-           output = `bin/rails db:migrate:status`
+        rails "db:rollback", "STEP=2"
+        output = rails("db:migrate:status")
 
-           assert_match(/down\s+\d{3,}\s+Create users/, output)
-           assert_match(/down\s+\d{3,}\s+Add email to users/, output)
+        assert_match(/down\s+\d{3,}\s+Create users/, output)
+        assert_match(/down\s+\d{3,}\s+Add email to users/, output)
 
-           `bin/rails db:migrate:redo`
-           output = `bin/rails db:migrate:status`
+        rails "db:migrate:redo"
+        output = rails("db:migrate:status")
 
-           assert_match(/up\s+\d{3,}\s+Create users/, output)
-           assert_match(/up\s+\d{3,}\s+Add email to users/, output)
-        end
+        assert_match(/up\s+\d{3,}\s+Create users/, output)
+        assert_match(/up\s+\d{3,}\s+Add email to users/, output)
       end
 
-      test 'running migrations with not timestamp head migration files' do
-        Dir.chdir(app_path) do
-
-          app_file "db/migrate/1_one_migration.rb", <<-MIGRATION
-            class OneMigration < ActiveRecord::Migration::Current
-            end
-          MIGRATION
+      test "running migrations with not timestamp head migration files" do
+        app_file "db/migrate/1_one_migration.rb", <<-MIGRATION
+          class OneMigration < ActiveRecord::Migration::Current
+          end
+        MIGRATION
 
-          app_file "db/migrate/02_two_migration.rb", <<-MIGRATION
-            class TwoMigration < ActiveRecord::Migration::Current
-            end
-          MIGRATION
+        app_file "db/migrate/02_two_migration.rb", <<-MIGRATION
+          class TwoMigration < ActiveRecord::Migration::Current
+          end
+        MIGRATION
 
-          `bin/rails db:migrate`
+        rails "db:migrate"
 
-           output = `bin/rails db:migrate:status`
+        output = rails("db:migrate:status")
 
-           assert_match(/up\s+001\s+One migration/, output)
-           assert_match(/up\s+002\s+Two migration/, output)
-        end
+        assert_match(/up\s+001\s+One migration/, output)
+        assert_match(/up\s+002\s+Two migration/, output)
       end
 
-      test 'schema generation when dump_schema_after_migration is set' do
-        add_to_config('config.active_record.dump_schema_after_migration = false')
+      test "schema generation when dump_schema_after_migration is set" do
+        add_to_config("config.active_record.dump_schema_after_migration = false")
 
         Dir.chdir(app_path) do
-          `bin/rails generate model book title:string`
-          output = `bin/rails generate model author name:string`
+          rails "generate", "model", "book", "title:string"
+          output = rails("generate", "model", "author", "name:string")
           version = output =~ %r{[^/]+db/migrate/(\d+)_create_authors\.rb} && $1
 
-          `bin/rails db:migrate db:rollback db:forward db:migrate:up db:migrate:down VERSION=#{version}`
+          rails "db:migrate", "db:rollback", "db:forward", "db:migrate:up", "db:migrate:down", "VERSION=#{version}"
           assert !File.exist?("db/schema.rb"), "should not dump schema when configured not to"
         end
 
-        add_to_config('config.active_record.dump_schema_after_migration = true')
+        add_to_config("config.active_record.dump_schema_after_migration = true")
 
         Dir.chdir(app_path) do
-          `bin/rails generate model reviews book_id:integer`
-          `bin/rails db:migrate`
+          rails "generate", "model", "reviews", "book_id:integer"
+          rails "db:migrate"
 
           structure_dump = File.read("db/schema.rb")
           assert_match(/create_table "reviews"/, structure_dump)
         end
       end
 
-      test 'default schema generation after migration' do
+      test "default schema generation after migration" do
         Dir.chdir(app_path) do
-          `bin/rails generate model book title:string;
-           bin/rails db:migrate`
+          rails "generate", "model", "book", "title:string"
+          rails "db:migrate"
 
           structure_dump = File.read("db/schema.rb")
           assert_match(/create_table "books"/, structure_dump)
         end
       end
 
-      test 'test migration status migrated file is deleted' do
+      test "migration status migrated file is deleted" do
         Dir.chdir(app_path) do
-          `bin/rails generate model user username:string password:string;
-           bin/rails generate migration add_email_to_users email:string;
-           bin/rails db:migrate
-           rm db/migrate/*email*.rb`
+          rails "generate", "model", "user", "username:string", "password:string"
+          rails "generate", "migration", "add_email_to_users", "email:string"
+          rails "db:migrate"
+          `rm db/migrate/*email*.rb`
 
-          output = `bin/rails db:migrate:status`
-          File.write('test.txt', output)
+          output = rails("db:migrate:status")
 
           assert_match(/up\s+\d{14}\s+Create users/, output)
           assert_match(/up\s+\d{14}\s+\** NO FILE \**/, output)
diff --git a/railties/test/application/rake/notes_test.rb b/railties/test/application/rake/notes_test.rb
index 50def9beb0..8e9fe9b6b4 100644
--- a/railties/test/application/rake/notes_test.rb
+++ b/railties/test/application/rake/notes_test.rb
@@ -1,5 +1,7 @@
+# frozen_string_literal: true
+
 require "isolation/abstract_unit"
-require 'rails/source_annotation_extractor'
+require "rails/source_annotation_extractor"
 
 module ApplicationTests
   module RakeTests
@@ -17,15 +19,15 @@ module ApplicationTests
         teardown_app
       end
 
-      test 'notes finds notes for certain file_types' do
+      test "notes finds notes for certain file_types" do
         app_file "app/views/home/index.html.erb", "<% # TODO: note in erb %>"
         app_file "app/assets/javascripts/application.js", "// TODO: note in js"
         app_file "app/assets/stylesheets/application.css", "// TODO: note in css"
         app_file "app/controllers/application_controller.rb", 1000.times.map { "" }.join("\n") << "# TODO: note in ruby"
         app_file "lib/tasks/task.rake", "# TODO: note in rake"
-        app_file 'app/views/home/index.html.builder', '# TODO: note in builder'
-        app_file 'config/locales/en.yml', '# TODO: note in yml'
-        app_file 'config/locales/en.yaml', '# TODO: note in yaml'
+        app_file "app/views/home/index.html.builder", "# TODO: note in builder"
+        app_file "config/locales/en.yml", "# TODO: note in yml"
+        app_file "config/locales/en.yaml", "# TODO: note in yaml"
         app_file "app/views/home/index.ruby", "# TODO: note in ruby"
 
         run_rake_notes do |output, lines|
@@ -43,7 +45,7 @@ module ApplicationTests
         end
       end
 
-      test 'notes finds notes in default directories' do
+      test "notes finds notes in default directories" do
         app_file "app/controllers/some_controller.rb", "# TODO: note in app directory"
         app_file "config/initializers/some_initializer.rb", "# TODO: note in config directory"
         app_file "db/some_seeds.rb", "# TODO: note in db directory"
@@ -65,7 +67,7 @@ module ApplicationTests
         end
       end
 
-      test 'notes finds notes in custom directories' do
+      test "notes finds notes in custom directories" do
         app_file "app/controllers/some_controller.rb", "# TODO: note in app directory"
         app_file "config/initializers/some_initializer.rb", "# TODO: note in config directory"
         app_file "db/some_seeds.rb", "# TODO: note in db directory"
@@ -88,9 +90,10 @@ module ApplicationTests
         end
       end
 
-      test 'custom rake task finds specific notes in specific directories' do
+      test "custom rake task finds specific notes in specific directories" do
         app_file "app/controllers/some_controller.rb", "# TODO: note in app directory"
-        app_file "lib/some_file.rb", "# OPTIMIZE: note in lib directory\n" << "# FIXME: note in lib directory"
+        app_file "lib/some_file.rb", "# OPTIMIZE: note in lib directory\n" \
+          "# FIXME: note in lib directory"
         app_file "test/some_test.rb", 1000.times.map { "" }.join("\n") << "# TODO: note in test directory"
 
         app_file "lib/tasks/notes_custom.rake", <<-EOS
@@ -113,7 +116,7 @@ module ApplicationTests
         end
       end
 
-      test 'register a new extension' do
+      test "register a new extension" do
         add_to_config "config.assets.precompile = []"
         add_to_config %q{ config.annotations.register_extensions("scss", "sass") { |annotation| /\/\/\s*(#{annotation}):?\s*(.*)$/ } }
         app_file "app/assets/stylesheets/application.css.scss", "// TODO: note in scss"
@@ -126,32 +129,43 @@ module ApplicationTests
         end
       end
 
+      test "register additional directories" do
+        app_file "spec/spec_helper.rb", "# TODO: note in spec"
+        app_file "spec/models/user_spec.rb", "# TODO: note in model spec"
+        add_to_config ' config.annotations.register_directories("spec") '
+
+        run_rake_notes do |output, lines|
+          assert_match(/note in spec/, output)
+          assert_match(/note in model spec/, output)
+          assert_equal 2, lines.size
+        end
+      end
+
       private
 
-      def run_rake_notes(command = 'bin/rails notes')
-        boot_rails
-        load_tasks
+        def run_rake_notes(command = "bin/rails notes")
+          boot_rails
+          load_tasks
 
-        Dir.chdir(app_path) do
-          output = `#{command}`
-          lines  = output.scan(/\[([0-9\s]+)\]\s/).flatten
+          Dir.chdir(app_path) do
+            output = `#{command}`
+            lines  = output.scan(/\[([0-9\s]+)\]\s/).flatten
 
-          yield output, lines
+            yield output, lines
+          end
         end
-      end
 
-      def load_tasks
-        require 'rake'
-        require 'rdoc/task'
-        require 'rake/testtask'
+        def load_tasks
+          require "rake"
+          require "rdoc/task"
+          require "rake/testtask"
 
-        Rails.application.load_tasks
-      end
+          Rails.application.load_tasks
+        end
 
-      def boot_rails
-        super
-        require "#{app_path}/config/environment"
-      end
+        def boot_rails
+          require "#{app_path}/config/environment"
+        end
     end
   end
 end
diff --git a/railties/test/application/rake/restart_test.rb b/railties/test/application/rake/restart_test.rb
index 30f662a9be..8614560bf2 100644
--- a/railties/test/application/rake/restart_test.rb
+++ b/railties/test/application/rake/restart_test.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require "isolation/abstract_unit"
 
 module ApplicationTests
@@ -7,40 +9,30 @@ module ApplicationTests
 
       def setup
         build_app
-        boot_rails
       end
 
       def teardown
         teardown_app
       end
 
-      test 'rake restart touches tmp/restart.txt' do
+      test "rails restart touches tmp/restart.txt" do
         Dir.chdir(app_path) do
-          `rake restart`
+          rails "restart"
           assert File.exist?("tmp/restart.txt")
 
           prev_mtime = File.mtime("tmp/restart.txt")
           sleep(1)
-          `rake restart`
+          rails "restart"
           curr_mtime = File.mtime("tmp/restart.txt")
           assert_not_equal prev_mtime, curr_mtime
         end
       end
 
-      test 'rake restart should work even if tmp folder does not exist' do
-        Dir.chdir(app_path) do
-          FileUtils.remove_dir('tmp')
-          `rake restart`
-          assert File.exist?('tmp/restart.txt')
-        end
-      end
-
-      test 'rake restart removes server.pid also' do
+      test "rails restart should work even if tmp folder does not exist" do
         Dir.chdir(app_path) do
-          FileUtils.mkdir_p("tmp/pids")
-          FileUtils.touch("tmp/pids/server.pid")
-          `rake restart`
-          assert_not File.exist?("tmp/pids/server.pid")
+          FileUtils.remove_dir("tmp")
+          rails "restart"
+          assert File.exist?("tmp/restart.txt")
         end
       end
     end
diff --git a/railties/test/application/rake/tmp_test.rb b/railties/test/application/rake/tmp_test.rb
new file mode 100644
index 0000000000..048fd7adcc
--- /dev/null
+++ b/railties/test/application/rake/tmp_test.rb
@@ -0,0 +1,43 @@
+# frozen_string_literal: true
+
+require "isolation/abstract_unit"
+
+module ApplicationTests
+  module RakeTests
+    class TmpTest < ActiveSupport::TestCase
+      include ActiveSupport::Testing::Isolation
+
+      def setup
+        build_app
+      end
+
+      def teardown
+        teardown_app
+      end
+
+      test "tmp:clear clear cache, socket and screenshot files" do
+        Dir.chdir(app_path) do
+          FileUtils.mkdir_p("tmp/cache")
+          FileUtils.touch("tmp/cache/cache_file")
+
+          FileUtils.mkdir_p("tmp/sockets")
+          FileUtils.touch("tmp/sockets/socket_file")
+
+          FileUtils.mkdir_p("tmp/screenshots")
+          FileUtils.touch("tmp/screenshots/fail.png")
+
+          rails "tmp:clear"
+
+          assert_not File.exist?("tmp/cache/cache_file")
+          assert_not File.exist?("tmp/sockets/socket_file")
+          assert_not File.exist?("tmp/screenshots/fail.png")
+        end
+      end
+
+      test "tmp:clear should work if folder missing" do
+        FileUtils.remove_dir("#{app_path}/tmp")
+        rails "tmp:clear"
+      end
+    end
+  end
+end
diff --git a/railties/test/application/rake_test.rb b/railties/test/application/rake_test.rb
index badb9ecdd6..5a6404bd0a 100644
--- a/railties/test/application/rake_test.rb
+++ b/railties/test/application/rake_test.rb
@@ -1,13 +1,15 @@
+# frozen_string_literal: true
+
 require "isolation/abstract_unit"
+require "env_helpers"
 require "active_support/core_ext/string/strip"
 
 module ApplicationTests
   class RakeTest < ActiveSupport::TestCase
-    include ActiveSupport::Testing::Isolation
+    include ActiveSupport::Testing::Isolation, EnvHelpers
 
     def setup
       build_app
-      boot_rails
     end
 
     def teardown
@@ -25,20 +27,20 @@ module ApplicationTests
     end
 
     test "task is protected when previous migration was production" do
-      Dir.chdir(app_path) do
-        output = `bin/rails generate model product name:string;
-         env RAILS_ENV=production bin/rails db:create db:migrate;
-         env RAILS_ENV=production bin/rails db:test:prepare test 2>&1`
+      with_rails_env "production" do
+        rails "generate", "model", "product", "name:string"
+        rails "db:create", "db:migrate"
+        output = rails("db:test:prepare", allow_failure: true)
 
         assert_match(/ActiveRecord::ProtectedEnvironmentError/, output)
       end
     end
 
     def test_not_protected_when_previous_migration_was_not_production
-      Dir.chdir(app_path) do
-        output = `bin/rails generate model product name:string;
-         env RAILS_ENV=test bin/rails db:create db:migrate;
-         env RAILS_ENV=test bin/rails db:test:prepare test 2>&1`
+      with_rails_env "test" do
+        rails "generate", "model", "product", "name:string"
+        rails "db:create", "db:migrate"
+        output = rails("db:test:prepare", "test")
 
         refute_match(/ActiveRecord::ProtectedEnvironmentError/, output)
       end
@@ -55,7 +57,7 @@ module ApplicationTests
         Rails.application.initialize!
       RUBY
 
-      assert_match("SuperMiddleware", Dir.chdir(app_path){ `bin/rails middleware` })
+      assert_match("SuperMiddleware", rails("middleware"))
     end
 
     def test_initializers_are_executed_in_rake_tasks
@@ -70,7 +72,7 @@ module ApplicationTests
         end
       RUBY
 
-      output = Dir.chdir(app_path){ `bin/rails do_nothing` }
+      output = rails("do_nothing")
       assert_match "Doing something...", output
     end
 
@@ -83,7 +85,7 @@ module ApplicationTests
         end
       RUBY
 
-      app_file 'app/models/hello.rb', <<-RUBY
+      app_file "app/models/hello.rb", <<-RUBY
         class Hello
           def world
             puts 'Hello world'
@@ -91,35 +93,34 @@ module ApplicationTests
         end
       RUBY
 
-      output = Dir.chdir(app_path) { `bin/rails do_nothing` }
-      assert_match 'Hello world', output
+      output = rails("do_nothing")
+      assert_match "Hello world", output
     end
 
     def test_should_not_eager_load_model_for_rake
       add_to_config <<-RUBY
         rake_tasks do
           task do_nothing: :environment do
+            puts 'There is nothing'
           end
         end
       RUBY
 
-      add_to_env_config 'production', <<-RUBY
+      add_to_env_config "production", <<-RUBY
         config.eager_load = true
       RUBY
 
-      app_file 'app/models/hello.rb', <<-RUBY
+      app_file "app/models/hello.rb", <<-RUBY
         raise 'should not be pre-required for rake even eager_load=true'
       RUBY
 
-      Dir.chdir(app_path) do
-        assert system('bin/rails do_nothing RAILS_ENV=production'),
-               'should not be pre-required for rake even eager_load=true'
-      end
+      output = rails("do_nothing", "RAILS_ENV=production")
+      assert_match "There is nothing", output
     end
 
     def test_code_statistics_sanity
-      assert_match "Code LOC: 26     Test LOC: 0     Code to Test Ratio: 1:0.0",
-        Dir.chdir(app_path) { `bin/rails stats` }
+      assert_match "Code LOC: 25     Test LOC: 0     Code to Test Ratio: 1:0.0",
+        rails("stats")
     end
 
     def test_rails_routes_calls_the_route_inspector
@@ -129,49 +130,36 @@ module ApplicationTests
         end
       RUBY
 
-      output = Dir.chdir(app_path){ `bin/rails routes` }
-      assert_equal "Prefix Verb URI Pattern     Controller#Action\n  cart GET  /cart(.:format) cart#show\n", output
-    end
-
-    def test_rails_routes_with_controller_environment
-      app_file "config/routes.rb", <<-RUBY
-        Rails.application.routes.draw do
-          get '/cart', to: 'cart#show'
-          get '/basketball', to: 'basketball#index'
-        end
-      RUBY
-
-      output = Dir.chdir(app_path){ `bin/rails routes CONTROLLER=cart` }
-      assert_equal ["Passing `CONTROLLER` to `bin/rails routes` is deprecated and will be removed in Rails 5.1.",
-                    "Please use `bin/rails routes -c controller_name` instead.",
-                    "Prefix Verb URI Pattern     Controller#Action",
-                    "  cart GET  /cart(.:format) cart#show\n"].join("\n"), output
-
-      output = Dir.chdir(app_path){ `bin/rails routes -c cart` }
-      assert_equal "Prefix Verb URI Pattern     Controller#Action\n  cart GET  /cart(.:format) cart#show\n", output
+      output = rails("routes")
+      assert_equal <<-MESSAGE.strip_heredoc, output
+                              Prefix Verb URI Pattern                                                                       Controller#Action
+                                cart GET  /cart(.:format)                                                                   cart#show
+                  rails_service_blob GET  /rails/active_storage/blobs/:signed_id/*filename(.:format)                        active_storage/blobs#show
+                rails_blob_variation GET  /rails/active_storage/variants/:signed_blob_id/:variation_key/*filename(.:format) active_storage/variants#show
+                  rails_blob_preview GET  /rails/active_storage/previews/:signed_blob_id/:variation_key/*filename(.:format) active_storage/previews#show
+                  rails_disk_service GET  /rails/active_storage/disk/:encoded_key/*filename(.:format)                       active_storage/disk#show
+           update_rails_disk_service PUT  /rails/active_storage/disk/:encoded_token(.:format)                               active_storage/disk#update
+                rails_direct_uploads POST /rails/active_storage/direct_uploads(.:format)                                    active_storage/direct_uploads#create
+      MESSAGE
     end
 
-    def test_rails_routes_with_namespaced_controller_environment
+    def test_singular_resource_output_in_rake_routes
       app_file "config/routes.rb", <<-RUBY
         Rails.application.routes.draw do
-          namespace :admin do
-            resource :post
-          end
+          resource :post
         end
       RUBY
-      expected_output = ["         Prefix Verb   URI Pattern                Controller#Action",
-                         "     admin_post POST   /admin/post(.:format)      admin/posts#create",
-                         " new_admin_post GET    /admin/post/new(.:format)  admin/posts#new",
-                         "edit_admin_post GET    /admin/post/edit(.:format) admin/posts#edit",
-                         "                GET    /admin/post(.:format)      admin/posts#show",
-                         "                PATCH  /admin/post(.:format)      admin/posts#update",
-                         "                PUT    /admin/post(.:format)      admin/posts#update",
-                         "                DELETE /admin/post(.:format)      admin/posts#destroy\n"].join("\n")
 
-      output = Dir.chdir(app_path){ `bin/rails routes -c Admin::PostController` }
-      assert_equal expected_output, output
+      expected_output = ["   Prefix Verb   URI Pattern          Controller#Action",
+                         " new_post GET    /post/new(.:format)  posts#new",
+                         "edit_post GET    /post/edit(.:format) posts#edit",
+                         "     post GET    /post(.:format)      posts#show",
+                         "          PATCH  /post(.:format)      posts#update",
+                         "          PUT    /post(.:format)      posts#update",
+                         "          DELETE /post(.:format)      posts#destroy",
+                         "          POST   /post(.:format)      posts#create\n"].join("\n")
 
-      output = Dir.chdir(app_path){ `bin/rails routes -c PostController` }
+      output = rails("routes", "-c", "PostController")
       assert_equal expected_output, output
     end
 
@@ -184,13 +172,24 @@ module ApplicationTests
         end
       RUBY
 
-      output = Dir.chdir(app_path){ `bin/rails routes -g show` }
-      assert_equal "Prefix Verb URI Pattern     Controller#Action\n  cart GET  /cart(.:format) cart#show\n", output
+      output = rails("routes", "-g", "show")
+      assert_equal <<-MESSAGE.strip_heredoc, output
+                              Prefix Verb URI Pattern                                                                       Controller#Action
+                                cart GET  /cart(.:format)                                                                   cart#show
+                  rails_service_blob GET  /rails/active_storage/blobs/:signed_id/*filename(.:format)                        active_storage/blobs#show
+                rails_blob_variation GET  /rails/active_storage/variants/:signed_blob_id/:variation_key/*filename(.:format) active_storage/variants#show
+                  rails_blob_preview GET  /rails/active_storage/previews/:signed_blob_id/:variation_key/*filename(.:format) active_storage/previews#show
+                  rails_disk_service GET  /rails/active_storage/disk/:encoded_key/*filename(.:format)                       active_storage/disk#show
+      MESSAGE
 
-      output = Dir.chdir(app_path){ `bin/rails routes -g POST` }
-      assert_equal "Prefix Verb URI Pattern     Controller#Action\n       POST /cart(.:format) cart#create\n", output
+      output = rails("routes", "-g", "POST")
+      assert_equal <<-MESSAGE.strip_heredoc, output
+                              Prefix Verb URI Pattern                                    Controller#Action
+                                     POST /cart(.:format)                                cart#create
+                rails_direct_uploads POST /rails/active_storage/direct_uploads(.:format) active_storage/direct_uploads#create
+      MESSAGE
 
-      output = Dir.chdir(app_path){ `bin/rails routes -g basketballs` }
+      output = rails("routes", "-g", "basketballs")
       assert_equal "     Prefix Verb URI Pattern            Controller#Action\n" \
                    "basketballs GET  /basketballs(.:format) basketball#index\n", output
     end
@@ -203,28 +202,54 @@ module ApplicationTests
         end
       RUBY
 
-      output = Dir.chdir(app_path){ `bin/rails routes -c cart` }
+      output = rails("routes", "-c", "cart")
       assert_equal "Prefix Verb URI Pattern     Controller#Action\n  cart GET  /cart(.:format) cart#show\n", output
 
-      output = Dir.chdir(app_path){ `bin/rails routes -c Cart` }
+      output = rails("routes", "-c", "Cart")
       assert_equal "Prefix Verb URI Pattern     Controller#Action\n  cart GET  /cart(.:format) cart#show\n", output
 
-      output = Dir.chdir(app_path){ `bin/rails routes -c CartController` }
+      output = rails("routes", "-c", "CartController")
       assert_equal "Prefix Verb URI Pattern     Controller#Action\n  cart GET  /cart(.:format) cart#show\n", output
     end
 
-    def test_rails_routes_displays_message_when_no_routes_are_defined
+    def test_rails_routes_with_namespaced_controller_search_key
       app_file "config/routes.rb", <<-RUBY
         Rails.application.routes.draw do
+          namespace :admin do
+            resource :post
+          end
         end
       RUBY
+      expected_output = ["         Prefix Verb   URI Pattern                Controller#Action",
+                         " new_admin_post GET    /admin/post/new(.:format)  admin/posts#new",
+                         "edit_admin_post GET    /admin/post/edit(.:format) admin/posts#edit",
+                         "     admin_post GET    /admin/post(.:format)      admin/posts#show",
+                         "                PATCH  /admin/post(.:format)      admin/posts#update",
+                         "                PUT    /admin/post(.:format)      admin/posts#update",
+                         "                DELETE /admin/post(.:format)      admin/posts#destroy",
+                         "                POST   /admin/post(.:format)      admin/posts#create\n"].join("\n")
 
-      assert_equal <<-MESSAGE.strip_heredoc, Dir.chdir(app_path){ `bin/rails routes` }
-        You don't have any routes defined!
+      output = rails("routes", "-c", "Admin::PostController")
+      assert_equal expected_output, output
 
-        Please add some routes in config/routes.rb.
+      output = rails("routes", "-c", "PostController")
+      assert_equal expected_output, output
+    end
 
-        For more information about routes, see the Rails guide: http://guides.rubyonrails.org/routing.html.
+    def test_rails_routes_displays_message_when_no_routes_are_defined
+      app_file "config/routes.rb", <<-RUBY
+        Rails.application.routes.draw do
+        end
+      RUBY
+
+      assert_equal <<-MESSAGE.strip_heredoc, rails("routes")
+                              Prefix Verb URI Pattern                                                                       Controller#Action
+                  rails_service_blob GET  /rails/active_storage/blobs/:signed_id/*filename(.:format)                        active_storage/blobs#show
+                rails_blob_variation GET  /rails/active_storage/variants/:signed_blob_id/:variation_key/*filename(.:format) active_storage/variants#show
+                  rails_blob_preview GET  /rails/active_storage/previews/:signed_blob_id/:variation_key/*filename(.:format) active_storage/previews#show
+                  rails_disk_service GET  /rails/active_storage/disk/:encoded_key/*filename(.:format)                       active_storage/disk#show
+           update_rails_disk_service PUT  /rails/active_storage/disk/:encoded_token(.:format)                               active_storage/disk#update
+                rails_direct_uploads POST /rails/active_storage/direct_uploads(.:format)                                    active_storage/direct_uploads#create
       MESSAGE
     end
 
@@ -235,8 +260,18 @@ module ApplicationTests
         end
       RUBY
 
-      output = Dir.chdir(app_path){ `bin/rake --rakefile Rakefile routes` }
-      assert_equal "Prefix Verb URI Pattern     Controller#Action\n  cart GET  /cart(.:format) cart#show\n", output
+      output = Dir.chdir(app_path) { `bin/rake --rakefile Rakefile routes` }
+
+      assert_equal <<-MESSAGE.strip_heredoc, output
+                              Prefix Verb URI Pattern                                                                       Controller#Action
+                                cart GET  /cart(.:format)                                                                   cart#show
+                  rails_service_blob GET  /rails/active_storage/blobs/:signed_id/*filename(.:format)                        active_storage/blobs#show
+                rails_blob_variation GET  /rails/active_storage/variants/:signed_blob_id/:variation_key/*filename(.:format) active_storage/variants#show
+                  rails_blob_preview GET  /rails/active_storage/previews/:signed_blob_id/:variation_key/*filename(.:format) active_storage/previews#show
+                  rails_disk_service GET  /rails/active_storage/disk/:encoded_key/*filename(.:format)                       active_storage/disk#show
+           update_rails_disk_service PUT  /rails/active_storage/disk/:encoded_token(.:format)                               active_storage/disk#update
+                rails_direct_uploads POST /rails/active_storage/direct_uploads(.:format)                                    active_storage/direct_uploads#create
+      MESSAGE
     end
 
     def test_logger_is_flushed_when_exiting_production_rake_tasks
@@ -248,44 +283,37 @@ module ApplicationTests
         end
       RUBY
 
-      output = Dir.chdir(app_path){ `bin/rails log_something RAILS_ENV=production && cat log/production.log` }
-      assert_match "Sample log message", output
+      rails "log_something", "RAILS_ENV=production"
+      assert_match "Sample log message", File.read("#{app_path}/log/production.log")
     end
 
     def test_loading_specific_fixtures
-      Dir.chdir(app_path) do
-        `bin/rails generate model user username:string password:string;
-         bin/rails generate model product name:string;
-         bin/rails db:migrate`
-      end
+      rails "generate", "model", "user", "username:string", "password:string"
+      rails "generate", "model", "product", "name:string"
+      rails "db:migrate"
 
       require "#{rails_root}/config/environment"
 
       # loading a specific fixture
-      errormsg = Dir.chdir(app_path) { `bin/rails db:fixtures:load FIXTURES=products` }
-      assert $?.success?, errormsg
+      rails "db:fixtures:load", "FIXTURES=products"
 
       assert_equal 2, ::AppTemplate::Application::Product.count
       assert_equal 0, ::AppTemplate::Application::User.count
     end
 
     def test_loading_only_yml_fixtures
-      Dir.chdir(app_path) do
-        `bin/rails db:migrate`
-      end
+      rails "db:migrate"
 
       app_file "test/fixtures/products.csv", ""
 
       require "#{rails_root}/config/environment"
-      errormsg = Dir.chdir(app_path) { `bin/rails db:fixtures:load` }
-      assert $?.success?, errormsg
+      rails "db:fixtures:load"
     end
 
     def test_scaffold_tests_pass_by_default
-      output = Dir.chdir(app_path) do
-        `bin/rails generate scaffold user username:string password:string;
-         RAILS_ENV=test bin/rails db:migrate test`
-      end
+      rails "generate", "scaffold", "user", "username:string", "password:string"
+      with_rails_env("test") { rails("db:migrate") }
+      output = rails("test")
 
       assert_match(/7 runs, 9 assertions, 0 failures, 0 errors/, output)
       assert_no_match(/Errors running/, output)
@@ -301,92 +329,68 @@ module ApplicationTests
         end
       RUBY
 
-      output = Dir.chdir(app_path) do
-        `bin/rails generate scaffold user username:string password:string;
-         RAILS_ENV=test bin/rails db:migrate test`
-      end
+      rails "generate", "scaffold", "user", "username:string", "password:string"
+      with_rails_env("test") { rails("db:migrate") }
+      output = rails("test")
 
       assert_match(/5 runs, 7 assertions, 0 failures, 0 errors/, output)
       assert_no_match(/Errors running/, output)
     end
 
     def test_scaffold_with_references_columns_tests_pass_by_default
-      output = Dir.chdir(app_path) do
-        `bin/rails generate model Product;
-         bin/rails generate model Cart;
-         bin/rails generate scaffold LineItems product:references cart:belongs_to;
-         RAILS_ENV=test bin/rails db:migrate test`
-      end
+      rails "generate", "model", "Product"
+      rails "generate", "model", "Cart"
+      rails "generate", "scaffold", "LineItems", "product:references", "cart:belongs_to"
+      with_rails_env("test") { rails("db:migrate") }
+      output = rails("test")
 
       assert_match(/7 runs, 9 assertions, 0 failures, 0 errors/, output)
       assert_no_match(/Errors running/, output)
     end
 
-    def test_db_test_clone_when_using_sql_format
-      add_to_config "config.active_record.schema_format = :sql"
-      output = Dir.chdir(app_path) do
-        `bin/rails generate scaffold user username:string;
-         bin/rails db:migrate;
-         bin/rails db:test:clone 2>&1 --trace`
-      end
-      assert_match(/Execute db:test:clone_structure/, output)
-    end
-
     def test_db_test_prepare_when_using_sql_format
       add_to_config "config.active_record.schema_format = :sql"
-      output = Dir.chdir(app_path) do
-        `bin/rails generate scaffold user username:string;
-         bin/rails db:migrate;
-         bin/rails db:test:prepare 2>&1 --trace`
-      end
+      rails "generate", "scaffold", "user", "username:string"
+      rails "db:migrate"
+      output = rails("db:test:prepare", "--trace")
       assert_match(/Execute db:test:load_structure/, output)
     end
 
     def test_rake_dump_structure_should_respect_db_structure_env_variable
-      Dir.chdir(app_path) do
-        # ensure we have a schema_migrations table to dump
-        `bin/rails db:migrate db:structure:dump SCHEMA=db/my_structure.sql`
-      end
-      assert File.exist?(File.join(app_path, 'db', 'my_structure.sql'))
+      # ensure we have a schema_migrations table to dump
+      rails "db:migrate", "db:structure:dump", "SCHEMA=db/my_structure.sql"
+      assert File.exist?(File.join(app_path, "db", "my_structure.sql"))
     end
 
     def test_rake_dump_structure_should_be_called_twice_when_migrate_redo
       add_to_config "config.active_record.schema_format = :sql"
 
-      output = Dir.chdir(app_path) do
-        `bin/rails g model post title:string;
-         bin/rails db:migrate:redo 2>&1 --trace;`
-      end
+      rails "g", "model", "post", "title:string"
+      output = rails("db:migrate:redo", "--trace")
 
       # expect only Invoke db:structure:dump (first_time)
       assert_no_match(/^\*\* Invoke db:structure:dump\s+$/, output)
     end
 
     def test_rake_dump_schema_cache
-      Dir.chdir(app_path) do
-        `bin/rails generate model post title:string;
-         bin/rails generate model product name:string;
-         bin/rails db:migrate db:schema:cache:dump`
-      end
-      assert File.exist?(File.join(app_path, 'db', 'schema_cache.dump'))
+      rails "generate", "model", "post", "title:string"
+      rails "generate", "model", "product", "name:string"
+      rails "db:migrate", "db:schema:cache:dump"
+      assert File.exist?(File.join(app_path, "db", "schema_cache.yml"))
     end
 
     def test_rake_clear_schema_cache
-      Dir.chdir(app_path) do
-        `bin/rails db:schema:cache:dump db:schema:cache:clear`
-      end
-      assert !File.exist?(File.join(app_path, 'db', 'schema_cache.dump'))
+      rails "db:schema:cache:dump", "db:schema:cache:clear"
+      assert !File.exist?(File.join(app_path, "db", "schema_cache.yml"))
     end
 
     def test_copy_templates
-      Dir.chdir(app_path) do
-        `bin/rails app:templates:copy`
-        %w(controller mailer scaffold).each do |dir|
-          assert File.exist?(File.join(app_path, 'lib', 'templates', 'erb', dir))
-        end
-        %w(controller helper scaffold_controller assets).each do |dir|
-          assert File.exist?(File.join(app_path, 'lib', 'templates', 'rails', dir))
-        end
+      rails "app:templates:copy"
+      %w(controller mailer scaffold).each do |dir|
+        assert File.exist?(File.join(app_path, "lib", "templates", "erb", dir))
+      end
+      %w(controller helper scaffold_controller assets).each do |dir|
+        assert File.exist?(File.join(app_path, "lib", "templates", "rails", dir))
       end
     end
 
@@ -394,18 +398,8 @@ module ApplicationTests
       app_file "config/initializers/dummy.rb", "puts 'Hello, World!'"
       app_file "template.rb", ""
 
-      output = Dir.chdir(app_path) do
-        `bin/rails app:template LOCATION=template.rb`
-      end
-
+      output = rails("app:template", "LOCATION=template.rb")
       assert_match(/Hello, World!/, output)
     end
-
-    def test_tmp_clear_should_work_if_folder_missing
-      FileUtils.remove_dir("#{app_path}/tmp")
-      errormsg = Dir.chdir(app_path) { `bin/rails tmp:clear` }
-      assert_predicate $?, :success?
-      assert_empty errormsg
-    end
   end
 end
diff --git a/railties/test/application/rendering_test.rb b/railties/test/application/rendering_test.rb
index b01febd768..3724886c54 100644
--- a/railties/test/application/rendering_test.rb
+++ b/railties/test/application/rendering_test.rb
@@ -1,5 +1,7 @@
-require 'isolation/abstract_unit'
-require 'rack/test'
+# frozen_string_literal: true
+
+require "isolation/abstract_unit"
+require "rack/test"
 
 module ApplicationTests
   class RoutingTest < ActiveSupport::TestCase
@@ -8,7 +10,6 @@ module ApplicationTests
 
     def setup
       build_app
-      boot_rails
     end
 
     def teardown
@@ -16,13 +17,13 @@ module ApplicationTests
     end
 
     test "Unknown format falls back to HTML template" do
-      app_file 'config/routes.rb', <<-RUBY
+      app_file "config/routes.rb", <<-RUBY
         Rails.application.routes.draw do
           get 'pages/:id', to: 'pages#show'
         end
       RUBY
 
-      app_file 'app/controllers/pages_controller.rb', <<-RUBY
+      app_file "app/controllers/pages_controller.rb", <<-RUBY
         class PagesController < ApplicationController
           layout false
 
@@ -31,14 +32,14 @@ module ApplicationTests
         end
       RUBY
 
-      app_file 'app/views/pages/show.html.erb', <<-RUBY
+      app_file "app/views/pages/show.html.erb", <<-RUBY
         <%= params[:id] %>
       RUBY
 
-      get '/pages/foo'
+      get "/pages/foo"
       assert_equal 200, last_response.status
 
-      get '/pages/foo.bar'
+      get "/pages/foo.bar"
       assert_equal 200, last_response.status
     end
   end
diff --git a/railties/test/application/routing_test.rb b/railties/test/application/routing_test.rb
index 93847c7aa9..bec038fb51 100644
--- a/railties/test/application/routing_test.rb
+++ b/railties/test/application/routing_test.rb
@@ -1,5 +1,7 @@
-require 'isolation/abstract_unit'
-require 'rack/test'
+# frozen_string_literal: true
+
+require "isolation/abstract_unit"
+require "rack/test"
 
 module ApplicationTests
   class RoutingTest < ActiveSupport::TestCase
@@ -8,7 +10,6 @@ module ApplicationTests
 
     def setup
       build_app
-      boot_rails
     end
 
     def teardown
@@ -61,24 +62,24 @@ module ApplicationTests
     test "root takes precedence over internal welcome controller" do
       app("development")
 
-      assert_welcome get('/')
+      assert_welcome get("/")
 
       controller :foo, <<-RUBY
         class FooController < ApplicationController
           def index
-            render text: "foo"
+            render plain: "foo"
           end
         end
       RUBY
 
-      app_file 'config/routes.rb', <<-RUBY
+      app_file "config/routes.rb", <<-RUBY
         Rails.application.routes.draw do
           root to: "foo#index"
         end
       RUBY
 
-      get '/'
-      assert_equal 'foo', last_response.body
+      get "/"
+      assert_equal "foo", last_response.body
     end
 
     test "rails/welcome in production" do
@@ -108,8 +109,8 @@ module ApplicationTests
     test "simple controller" do
       simple_controller
 
-      get '/foo'
-      assert_equal 'foo', last_response.body
+      get "/foo"
+      assert_equal "foo", last_response.body
     end
 
     test "simple controller with helper" do
@@ -121,7 +122,7 @@ module ApplicationTests
         end
       RUBY
 
-      app_file 'app/helpers/bar_helper.rb', <<-RUBY
+      app_file "app/helpers/bar_helper.rb", <<-RUBY
         module BarHelper
           def foo_or_bar?
             "bar"
@@ -129,18 +130,18 @@ module ApplicationTests
         end
       RUBY
 
-      app_file 'config/routes.rb', <<-RUBY
+      app_file "config/routes.rb", <<-RUBY
         Rails.application.routes.draw do
           get ':controller(/:action)'
         end
       RUBY
 
-      get '/foo'
-      assert_equal 'bar', last_response.body
+      get "/foo"
+      assert_equal "bar", last_response.body
     end
 
     test "mount rack app" do
-      app_file 'config/routes.rb', <<-RUBY
+      app_file "config/routes.rb", <<-RUBY
         Rails.application.routes.draw do
           mount lambda { |env| [200, {}, [env["PATH_INFO"]]] }, at: "/blog"
           # The line below is required because mount sometimes
@@ -149,35 +150,35 @@ module ApplicationTests
         end
       RUBY
 
-      get '/blog/archives'
-      assert_equal '/archives', last_response.body
+      get "/blog/archives"
+      assert_equal "/archives", last_response.body
     end
 
     test "mount named rack app" do
       controller :foo, <<-RUBY
         class FooController < ApplicationController
           def index
-            render text: my_blog_path
+            render plain: my_blog_path
           end
         end
       RUBY
 
-      app_file 'config/routes.rb', <<-RUBY
+      app_file "config/routes.rb", <<-RUBY
         Rails.application.routes.draw do
           mount lambda { |env| [200, {}, [env["PATH_INFO"]]] }, at: "/blog", as: "my_blog"
           get '/foo' => 'foo#index'
         end
       RUBY
 
-      get '/foo'
-      assert_equal '/blog', last_response.body
+      get "/foo"
+      assert_equal "/blog", last_response.body
     end
 
     test "multiple controllers" do
       controller :foo, <<-RUBY
         class FooController < ApplicationController
           def index
-            render text: "foo"
+            render plain: "foo"
           end
         end
       RUBY
@@ -185,59 +186,59 @@ module ApplicationTests
       controller :bar, <<-RUBY
         class BarController < ActionController::Base
           def index
-            render text: "bar"
+            render plain: "bar"
           end
         end
       RUBY
 
-      app_file 'config/routes.rb', <<-RUBY
+      app_file "config/routes.rb", <<-RUBY
         Rails.application.routes.draw do
           get ':controller(/:action)'
         end
       RUBY
 
-      get '/foo'
-      assert_equal 'foo', last_response.body
+      get "/foo"
+      assert_equal "foo", last_response.body
 
-      get '/bar'
-      assert_equal 'bar', last_response.body
+      get "/bar"
+      assert_equal "bar", last_response.body
     end
 
     test "nested controller" do
-      controller 'foo', <<-RUBY
+      controller "foo", <<-RUBY
         class FooController < ApplicationController
           def index
-            render text: "foo"
+            render plain: "foo"
           end
         end
       RUBY
 
-      controller 'admin/foo', <<-RUBY
+      controller "admin/foo", <<-RUBY
         module Admin
           class FooController < ApplicationController
             def index
-              render text: "admin::foo"
+              render plain: "admin::foo"
             end
           end
         end
       RUBY
 
-      app_file 'config/routes.rb', <<-RUBY
+      app_file "config/routes.rb", <<-RUBY
         Rails.application.routes.draw do
           get 'admin/foo', to: 'admin/foo#index'
           get 'foo', to: 'foo#index'
         end
       RUBY
 
-      get '/foo'
-      assert_equal 'foo', last_response.body
+      get "/foo"
+      assert_equal "foo", last_response.body
 
-      get '/admin/foo'
-      assert_equal 'admin::foo', last_response.body
+      get "/admin/foo"
+      assert_equal "admin::foo", last_response.body
     end
 
     test "routes appending blocks" do
-      app_file 'config/routes.rb', <<-RUBY
+      app_file "config/routes.rb", <<-RUBY
         Rails.application.routes.draw do
           get ':controller/:action'
         end
@@ -249,60 +250,108 @@ module ApplicationTests
         end
       R
 
-      app 'development'
+      app "development"
 
-      get '/win'
-      assert_equal 'WIN', last_response.body
+      get "/win"
+      assert_equal "WIN", last_response.body
 
-      app_file 'config/routes.rb', <<-R
+      app_file "config/routes.rb", <<-R
         Rails.application.routes.draw do
           get 'lol' => 'hello#index'
         end
       R
 
-      get '/win'
-      assert_equal 'WIN', last_response.body
+      get "/win"
+      assert_equal "WIN", last_response.body
     end
 
-    {"development" => "baz", "production" => "bar"}.each do |mode, expected|
+    {
+      "development" => ["baz", "http://www.apple.com", "/dashboard"],
+      "production"  => ["bar", "http://www.microsoft.com", "/profile"]
+    }.each do |mode, (expected_action, expected_url, expected_mapping)|
       test "reloads routes when configuration is changed in #{mode}" do
         controller :foo, <<-RUBY
           class FooController < ApplicationController
             def bar
-              render text: "bar"
+              render plain: "bar"
             end
 
             def baz
-              render text: "baz"
+              render plain: "baz"
+            end
+
+            def custom
+              render plain: custom_url
+            end
+
+            def mapping
+              render plain: url_for(User.new)
             end
           end
         RUBY
 
-        app_file 'config/routes.rb', <<-RUBY
+        app_file "app/models/user.rb", <<-RUBY
+          class User
+            extend ActiveModel::Naming
+            include ActiveModel::Conversion
+
+            def self.model_name
+              @_model_name ||= ActiveModel::Name.new(self.class, nil, "User")
+            end
+
+            def persisted?
+              false
+            end
+          end
+        RUBY
+
+        app_file "config/routes.rb", <<-RUBY
           Rails.application.routes.draw do
             get 'foo', to: 'foo#bar'
+            get 'custom', to: 'foo#custom'
+            get 'mapping', to: 'foo#mapping'
+
+            direct(:custom) { "http://www.microsoft.com" }
+            resolve("User") { "/profile" }
           end
         RUBY
 
         app(mode)
 
-        get '/foo'
-        assert_equal 'bar', last_response.body
+        get "/foo"
+        assert_equal "bar", last_response.body
 
-        app_file 'config/routes.rb', <<-RUBY
+        get "/custom"
+        assert_equal "http://www.microsoft.com", last_response.body
+
+        get "/mapping"
+        assert_equal "/profile", last_response.body
+
+        app_file "config/routes.rb", <<-RUBY
           Rails.application.routes.draw do
             get 'foo', to: 'foo#baz'
+            get 'custom', to: 'foo#custom'
+            get 'mapping', to: 'foo#mapping'
+
+            direct(:custom) { "http://www.apple.com" }
+            resolve("User") { "/dashboard" }
           end
         RUBY
 
         sleep 0.1
 
-        get '/foo'
-        assert_equal expected, last_response.body
+        get "/foo"
+        assert_equal expected_action, last_response.body
+
+        get "/custom"
+        assert_equal expected_url, last_response.body
+
+        get "/mapping"
+        assert_equal expected_mapping, last_response.body
       end
     end
 
-    test 'routes are loaded just after initialization' do
+    test "routes are loaded just after initialization" do
       require "#{app_path}/config/application"
 
       # Create the rack app just inside after initialize callback
@@ -310,17 +359,17 @@ module ApplicationTests
         ::InitializeRackApp = lambda { |env| [200, {}, ["InitializeRackApp"]] }
       end
 
-      app_file 'config/routes.rb', <<-RUBY
+      app_file "config/routes.rb", <<-RUBY
         Rails.application.routes.draw do
           get 'foo', to: ::InitializeRackApp
         end
       RUBY
 
-      get '/foo'
+      get "/foo"
       assert_equal "InitializeRackApp", last_response.body
     end
 
-    test 'reload_routes! is part of Rails.application API' do
+    test "reload_routes! is part of Rails.application API" do
       app("development")
       assert_nothing_raised do
         Rails.application.reload_routes!
@@ -328,36 +377,44 @@ module ApplicationTests
     end
 
     def test_root_path
-      app('development')
+      app("development")
 
       controller :foo, <<-RUBY
         class FooController < ApplicationController
           def index
-            render :text => "foo"
+            render plain: "foo"
           end
         end
       RUBY
 
-      app_file 'config/routes.rb', <<-RUBY
+      app_file "config/routes.rb", <<-RUBY
         Rails.application.routes.draw do
           get 'foo', :to => 'foo#index'
           root :to => 'foo#index'
         end
       RUBY
 
-      remove_file 'public/index.html'
+      remove_file "public/index.html"
 
-      get '/'
-      assert_equal 'foo', last_response.body
+      get "/"
+      assert_equal "foo", last_response.body
     end
 
-    test 'routes are added and removed when reloading' do
-      app('development')
+    test "routes are added and removed when reloading" do
+      app("development")
 
       controller :foo, <<-RUBY
         class FooController < ApplicationController
           def index
-            render text: "foo"
+            render plain: "foo"
+          end
+
+          def custom
+            render plain: custom_url
+          end
+
+          def mapping
+            render plain: url_for(User.new)
           end
         end
       RUBY
@@ -365,45 +422,74 @@ module ApplicationTests
       controller :bar, <<-RUBY
         class BarController < ApplicationController
           def index
-            render text: "bar"
+            render plain: "bar"
+          end
+        end
+      RUBY
+
+      app_file "app/models/user.rb", <<-RUBY
+        class User
+          extend ActiveModel::Naming
+          include ActiveModel::Conversion
+
+          def self.model_name
+            @_model_name ||= ActiveModel::Name.new(self.class, nil, "User")
+          end
+
+          def persisted?
+            false
           end
         end
       RUBY
 
-      app_file 'config/routes.rb', <<-RUBY
+      app_file "config/routes.rb", <<-RUBY
         Rails.application.routes.draw do
           get 'foo', to: 'foo#index'
         end
       RUBY
 
-      get '/foo'
-      assert_equal 'foo', last_response.body
-      assert_equal '/foo', Rails.application.routes.url_helpers.foo_path
+      get "/foo"
+      assert_equal "foo", last_response.body
+      assert_equal "/foo", Rails.application.routes.url_helpers.foo_path
 
-      get '/bar'
+      get "/bar"
       assert_equal 404, last_response.status
       assert_raises NoMethodError do
-        assert_equal '/bar', Rails.application.routes.url_helpers.bar_path
+        assert_equal "/bar", Rails.application.routes.url_helpers.bar_path
       end
 
-      app_file 'config/routes.rb', <<-RUBY
+      app_file "config/routes.rb", <<-RUBY
         Rails.application.routes.draw do
           get 'foo', to: 'foo#index'
           get 'bar', to: 'bar#index'
+
+          get 'custom', to: 'foo#custom'
+          direct(:custom) { 'http://www.apple.com' }
+
+          get 'mapping', to: 'foo#mapping'
+          resolve('User') { '/profile' }
         end
       RUBY
 
       Rails.application.reload_routes!
 
-      get '/foo'
-      assert_equal 'foo', last_response.body
-      assert_equal '/foo', Rails.application.routes.url_helpers.foo_path
+      get "/foo"
+      assert_equal "foo", last_response.body
+      assert_equal "/foo", Rails.application.routes.url_helpers.foo_path
+
+      get "/bar"
+      assert_equal "bar", last_response.body
+      assert_equal "/bar", Rails.application.routes.url_helpers.bar_path
 
-      get '/bar'
-      assert_equal 'bar', last_response.body
-      assert_equal '/bar', Rails.application.routes.url_helpers.bar_path
+      get "/custom"
+      assert_equal "http://www.apple.com", last_response.body
+      assert_equal "http://www.apple.com", Rails.application.routes.url_helpers.custom_url
 
-      app_file 'config/routes.rb', <<-RUBY
+      get "/mapping"
+      assert_equal "/profile", last_response.body
+      assert_equal "/profile", Rails.application.routes.url_helpers.polymorphic_path(User.new)
+
+      app_file "config/routes.rb", <<-RUBY
         Rails.application.routes.draw do
           get 'foo', to: 'foo#index'
         end
@@ -411,24 +497,36 @@ module ApplicationTests
 
       Rails.application.reload_routes!
 
-      get '/foo'
-      assert_equal 'foo', last_response.body
-      assert_equal '/foo', Rails.application.routes.url_helpers.foo_path
+      get "/foo"
+      assert_equal "foo", last_response.body
+      assert_equal "/foo", Rails.application.routes.url_helpers.foo_path
+
+      get "/bar"
+      assert_equal 404, last_response.status
+      assert_raises NoMethodError do
+        assert_equal "/bar", Rails.application.routes.url_helpers.bar_path
+      end
+
+      get "/custom"
+      assert_equal 404, last_response.status
+      assert_raises NoMethodError do
+        assert_equal "http://www.apple.com", Rails.application.routes.url_helpers.custom_url
+      end
 
-      get '/bar'
+      get "/mapping"
       assert_equal 404, last_response.status
       assert_raises NoMethodError do
-        assert_equal '/bar', Rails.application.routes.url_helpers.bar_path
+        assert_equal "/profile", Rails.application.routes.url_helpers.polymorphic_path(User.new)
       end
     end
 
-    test 'named routes are cleared when reloading' do
-      app('development')
+    test "named routes are cleared when reloading" do
+      app("development")
 
       controller :foo, <<-RUBY
         class FooController < ApplicationController
           def index
-            render text: "foo"
+            render plain: "foo"
           end
         end
       RUBY
@@ -436,63 +534,149 @@ module ApplicationTests
       controller :bar, <<-RUBY
         class BarController < ApplicationController
           def index
-            render text: "bar"
+            render plain: "bar"
+          end
+        end
+      RUBY
+
+      app_file "app/models/user.rb", <<-RUBY
+        class User
+          extend ActiveModel::Naming
+          include ActiveModel::Conversion
+
+          def self.model_name
+            @_model_name ||= ActiveModel::Name.new(self.class, nil, "User")
+          end
+
+          def persisted?
+            false
           end
         end
       RUBY
 
-      app_file 'config/routes.rb', <<-RUBY
+      app_file "config/routes.rb", <<-RUBY
         Rails.application.routes.draw do
           get ':locale/foo', to: 'foo#index', as: 'foo'
+          get 'users', to: 'foo#users', as: 'users'
+          direct(:microsoft) { 'http://www.microsoft.com' }
+          resolve('User') { '/profile' }
         end
       RUBY
 
-      get '/en/foo'
-      assert_equal 'foo', last_response.body
-      assert_equal '/en/foo', Rails.application.routes.url_helpers.foo_path(:locale => 'en')
+      get "/en/foo"
+      assert_equal "foo", last_response.body
+      assert_equal "/en/foo", Rails.application.routes.url_helpers.foo_path(locale: "en")
+      assert_equal "http://www.microsoft.com", Rails.application.routes.url_helpers.microsoft_url
+      assert_equal "/profile", Rails.application.routes.url_helpers.polymorphic_path(User.new)
 
-      app_file 'config/routes.rb', <<-RUBY
+      app_file "config/routes.rb", <<-RUBY
         Rails.application.routes.draw do
           get ':locale/bar', to: 'bar#index', as: 'foo'
+          get 'users', to: 'foo#users', as: 'users'
+          direct(:apple) { 'http://www.apple.com' }
         end
       RUBY
 
       Rails.application.reload_routes!
 
-      get '/en/foo'
+      get "/en/foo"
       assert_equal 404, last_response.status
 
-      get '/en/bar'
-      assert_equal 'bar', last_response.body
-      assert_equal '/en/bar', Rails.application.routes.url_helpers.foo_path(:locale => 'en')
+      get "/en/bar"
+      assert_equal "bar", last_response.body
+      assert_equal "/en/bar", Rails.application.routes.url_helpers.foo_path(locale: "en")
+      assert_equal "http://www.apple.com", Rails.application.routes.url_helpers.apple_url
+      assert_equal "/users", Rails.application.routes.url_helpers.polymorphic_path(User.new)
+
+      assert_raises NoMethodError do
+        assert_equal "http://www.microsoft.com", Rails.application.routes.url_helpers.microsoft_url
+      end
     end
 
-    test 'resource routing with irregular inflection' do
-      app_file 'config/initializers/inflection.rb', <<-RUBY
+    test "resource routing with irregular inflection" do
+      app_file "config/initializers/inflection.rb", <<-RUBY
         ActiveSupport::Inflector.inflections do |inflect|
           inflect.irregular 'yazi', 'yazilar'
         end
       RUBY
 
-      app_file 'config/routes.rb', <<-RUBY
+      app_file "config/routes.rb", <<-RUBY
         Rails.application.routes.draw do
           resources :yazilar
         end
       RUBY
 
-      controller 'yazilar', <<-RUBY
+      controller "yazilar", <<-RUBY
         class YazilarController < ApplicationController
           def index
-            render text: 'yazilar#index'
+            render plain: 'yazilar#index'
           end
         end
       RUBY
 
-      get '/yazilars'
+      get "/yazilars"
       assert_equal 404, last_response.status
 
-      get '/yazilar'
+      get "/yazilar"
       assert_equal 200, last_response.status
     end
+
+    test "reloading routes removes methods and doesn't undefine them" do
+      app_file "config/routes.rb", <<-RUBY
+        Rails.application.routes.draw do
+          get '/url', to: 'url#index'
+        end
+      RUBY
+
+      app_file "app/models/url_helpers.rb", <<-RUBY
+        module UrlHelpers
+          def foo_path
+            "/foo"
+          end
+        end
+      RUBY
+
+      app_file "app/models/context.rb", <<-RUBY
+        class Context
+          include UrlHelpers
+          include Rails.application.routes.url_helpers
+        end
+      RUBY
+
+      controller "url", <<-RUBY
+        class UrlController < ApplicationController
+          def index
+            context = Context.new
+            render plain: context.foo_path
+          end
+        end
+      RUBY
+
+      get "/url"
+      assert_equal "/foo", last_response.body
+
+      app_file "config/routes.rb", <<-RUBY
+        Rails.application.routes.draw do
+          get '/url', to: 'url#index'
+          get '/bar', to: 'foo#index', as: 'foo'
+        end
+      RUBY
+
+      Rails.application.reload_routes!
+
+      get "/url"
+      assert_equal "/bar", last_response.body
+
+      app_file "config/routes.rb", <<-RUBY
+        Rails.application.routes.draw do
+          get '/url', to: 'url#index'
+        end
+      RUBY
+
+      Rails.application.reload_routes!
+
+      get "/url"
+      assert_equal "/foo", last_response.body
+    end
   end
 end
diff --git a/railties/test/application/runner_test.rb b/railties/test/application/runner_test.rb
index 9f15ce5e85..aa5d495c97 100644
--- a/railties/test/application/runner_test.rb
+++ b/railties/test/application/runner_test.rb
@@ -1,5 +1,7 @@
-require 'isolation/abstract_unit'
-require 'env_helpers'
+# frozen_string_literal: true
+
+require "isolation/abstract_unit"
+require "env_helpers"
 
 module ApplicationTests
   class RunnerTest < ActiveSupport::TestCase
@@ -8,7 +10,6 @@ module ApplicationTests
 
     def setup
       build_app
-      boot_rails
 
       # Lets create a model so we have something to play with
       app_file "app/models/user.rb", <<-MODEL
@@ -25,15 +26,20 @@ module ApplicationTests
     end
 
     def test_should_include_runner_in_shebang_line_in_help_without_option
-      assert_match "/rails runner", Dir.chdir(app_path) { `bin/rails runner` }
+      assert_match "/rails runner", rails("runner", allow_failure: true)
     end
 
     def test_should_include_runner_in_shebang_line_in_help
-      assert_match "/rails runner", Dir.chdir(app_path) { `bin/rails runner --help` }
+      assert_match "/rails runner", rails("runner", "--help")
     end
 
     def test_should_run_ruby_statement
-      assert_match "42", Dir.chdir(app_path) { `bin/rails runner "puts User.count"` }
+      assert_match "42", rails("runner", "puts User.count")
+    end
+
+    def test_should_set_argv_when_running_code
+      output = rails("runner", "puts ARGV.join(',')", "--foo", "a1", "-b", "a2", "a3", "--moo")
+      assert_equal "--foo,a1,-b,a2,a3,--moo", output.chomp
     end
 
     def test_should_run_file
@@ -41,7 +47,16 @@ module ApplicationTests
       puts User.count
       SCRIPT
 
-      assert_match "42", Dir.chdir(app_path) { `bin/rails runner "bin/count_users.rb"` }
+      assert_match "42", rails("runner", "bin/count_users.rb")
+    end
+
+    def test_no_minitest_loaded_in_production_mode
+      app_file "bin/print_features.rb", <<-SCRIPT
+      p $LOADED_FEATURES.grep(/minitest/)
+      SCRIPT
+      assert_match "[]", Dir.chdir(app_path) {
+        `RAILS_ENV=production bin/rails runner "bin/print_features.rb"`
+      }
     end
 
     def test_should_set_dollar_0_to_file
@@ -49,7 +64,7 @@ module ApplicationTests
       puts $0
       SCRIPT
 
-      assert_match "bin/dollar0.rb", Dir.chdir(app_path) { `bin/rails runner "bin/dollar0.rb"` }
+      assert_match "bin/dollar0.rb", rails("runner", "bin/dollar0.rb")
     end
 
     def test_should_set_dollar_program_name_to_file
@@ -57,7 +72,23 @@ module ApplicationTests
       puts $PROGRAM_NAME
       SCRIPT
 
-      assert_match "bin/program_name.rb", Dir.chdir(app_path) { `bin/rails runner "bin/program_name.rb"` }
+      assert_match "bin/program_name.rb", rails("runner", "bin/program_name.rb")
+    end
+
+    def test_passes_extra_args_to_file
+      app_file "bin/program_name.rb", <<-SCRIPT
+      p ARGV
+      SCRIPT
+
+      assert_match %w( a b ).to_s, rails("runner", "bin/program_name.rb", "a", "b")
+    end
+
+    def test_should_run_stdin
+      app_file "bin/count_users.rb", <<-SCRIPT
+      puts User.count
+      SCRIPT
+
+      assert_match "42", Dir.chdir(app_path) { `cat bin/count_users.rb | bin/rails runner -` }
     end
 
     def test_with_hook
@@ -67,33 +98,47 @@ module ApplicationTests
         end
       RUBY
 
-      assert_match "true", Dir.chdir(app_path) { `bin/rails runner "puts Rails.application.config.ran"` }
+      assert_match "true", rails("runner", "puts Rails.application.config.ran")
     end
 
     def test_default_environment
-      assert_match "development", Dir.chdir(app_path) { `bin/rails runner "puts Rails.env"` }
+      assert_match "development", rails("runner", "puts Rails.env")
     end
 
     def test_runner_detects_syntax_errors
-      Dir.chdir(app_path) { `bin/rails runner "puts 'hello world" 2>&1` }
-      refute $?.success? 
+      output = rails("runner", "puts 'hello world", allow_failure: true)
+      assert_not $?.success?
+      assert_match "unterminated string meets end of file", output
     end
 
     def test_runner_detects_bad_script_name
-      Dir.chdir(app_path) { `bin/rails runner "iuiqwiourowe" 2>&1` }
-      refute $?.success? 
+      output = rails("runner", "iuiqwiourowe", allow_failure: true)
+      assert_not $?.success?
+      assert_match "undefined local variable or method `iuiqwiourowe' for", output
     end
 
     def test_environment_with_rails_env
       with_rails_env "production" do
-        assert_match "production", Dir.chdir(app_path) { `bin/rails runner "puts Rails.env"` }
+        assert_match "production", rails("runner", "puts Rails.env")
       end
     end
 
     def test_environment_with_rack_env
       with_rack_env "production" do
-        assert_match "production", Dir.chdir(app_path) { `bin/rails runner "puts Rails.env"` }
+        assert_match "production", rails("runner", "puts Rails.env")
+      end
+    end
+
+    def test_can_call_same_name_class_as_defined_in_thor
+      app_file "app/models/task.rb", <<-MODEL
+      class Task
+        def self.count
+          42
+        end
       end
+      MODEL
+
+      assert_match "42", rails("runner", "puts Task.count")
     end
   end
 end
diff --git a/railties/test/application/server_test.rb b/railties/test/application/server_test.rb
new file mode 100644
index 0000000000..a6093b5733
--- /dev/null
+++ b/railties/test/application/server_test.rb
@@ -0,0 +1,66 @@
+# frozen_string_literal: true
+
+require "isolation/abstract_unit"
+require "console_helpers"
+require "rails/command"
+require "rails/commands/server/server_command"
+
+module ApplicationTests
+  class ServerTest < ActiveSupport::TestCase
+    include ActiveSupport::Testing::Isolation
+    include ConsoleHelpers
+
+    def setup
+      build_app
+    end
+
+    def teardown
+      teardown_app
+    end
+
+    test "deprecate support of older `config.ru`" do
+      remove_file "config.ru"
+      app_file "config.ru", <<-RUBY
+        require_relative 'config/environment'
+        run AppTemplate::Application
+      RUBY
+
+      server = Rails::Server.new(config: "#{app_path}/config.ru")
+      server.app
+
+      log = File.read(Rails.application.config.paths["log"].first)
+      assert_match(/DEPRECATION WARNING: Use `Rails::Application` subclass to start the server is deprecated/, log)
+    end
+
+    test "restart rails server with custom pid file path" do
+      skip "PTY unavailable" unless available_pty?
+
+      File.open("#{app_path}/config/boot.rb", "w") do |f|
+        f.puts "ENV['BUNDLE_GEMFILE'] = '#{Bundler.default_gemfile.to_s}'"
+        f.puts "require 'bundler/setup'"
+      end
+
+      master, slave = PTY.open
+      pid = nil
+
+      begin
+        pid = Process.spawn("#{app_path}/bin/rails server -P tmp/dummy.pid", in: slave, out: slave, err: slave)
+        assert_output("Listening", master)
+
+        rails("restart")
+
+        assert_output("Restarting", master)
+        assert_output("Inherited", master)
+      ensure
+        kill(pid) if pid
+      end
+    end
+
+    private
+      def kill(pid)
+        Process.kill("TERM", pid)
+        Process.wait(pid)
+      rescue Errno::ESRCH
+      end
+  end
+end
diff --git a/railties/test/application/test_runner_test.rb b/railties/test/application/test_runner_test.rb
index 08759ab5a4..a01325fdb8 100644
--- a/railties/test/application/test_runner_test.rb
+++ b/railties/test/application/test_runner_test.rb
@@ -1,6 +1,8 @@
-require 'isolation/abstract_unit'
-require 'active_support/core_ext/string/strip'
-require 'env_helpers'
+# frozen_string_literal: true
+
+require "isolation/abstract_unit"
+require "active_support/core_ext/string/strip"
+require "env_helpers"
 
 module ApplicationTests
   class TestRunnerTest < ActiveSupport::TestCase
@@ -15,32 +17,56 @@ module ApplicationTests
       teardown_app
     end
 
+    def test_run_via_backwardscompatibility
+      require "minitest/rails_plugin"
+
+      assert_nothing_raised do
+        Minitest.run_via[:ruby] = true
+      end
+
+      assert Minitest.run_via[:ruby]
+    end
+
     def test_run_single_file
-      create_test_file :models, 'foo'
-      create_test_file :models, 'bar'
+      create_test_file :models, "foo"
+      create_test_file :models, "bar"
       assert_match "1 runs, 1 assertions, 0 failures", run_test_command("test/models/foo_test.rb")
     end
 
+    def test_run_single_file_with_absolute_path
+      create_test_file :models, "foo"
+      create_test_file :models, "bar"
+      assert_match "1 runs, 1 assertions, 0 failures", run_test_command("#{app_path}/test/models/foo_test.rb")
+    end
+
     def test_run_multiple_files
-      create_test_file :models,  'foo'
-      create_test_file :models,  'bar'
+      create_test_file :models,  "foo"
+      create_test_file :models,  "bar"
       assert_match "2 runs, 2 assertions, 0 failures", run_test_command("test/models/foo_test.rb test/models/bar_test.rb")
     end
 
+    def test_run_multiple_files_with_absolute_paths
+      create_test_file :models,  "foo"
+      create_test_file :controllers,  "foobar_controller"
+      create_test_file :models, "bar"
+
+      assert_match "2 runs, 2 assertions, 0 failures", run_test_command("#{app_path}/test/models/foo_test.rb #{app_path}/test/controllers/foobar_controller_test.rb")
+    end
+
     def test_run_file_with_syntax_error
-      app_file 'test/models/error_test.rb', <<-RUBY
+      app_file "test/models/error_test.rb", <<-RUBY
         require 'test_helper'
         def; end
       RUBY
 
-      error = capture(:stderr) { run_test_command('test/models/error_test.rb') }
+      error = capture(:stderr) { run_test_command("test/models/error_test.rb", stderr: true) }
       assert_match "syntax error", error
     end
 
     def test_run_models
-      create_test_file :models, 'foo'
-      create_test_file :models, 'bar'
-      create_test_file :controllers, 'foobar_controller'
+      create_test_file :models, "foo"
+      create_test_file :models, "bar"
+      create_test_file :controllers, "foobar_controller"
       run_test_command("test/models").tap do |output|
         assert_match "FooTest", output
         assert_match "BarTest", output
@@ -49,9 +75,9 @@ module ApplicationTests
     end
 
     def test_run_helpers
-      create_test_file :helpers, 'foo_helper'
-      create_test_file :helpers, 'bar_helper'
-      create_test_file :controllers, 'foobar_controller'
+      create_test_file :helpers, "foo_helper"
+      create_test_file :helpers, "bar_helper"
+      create_test_file :controllers, "foobar_controller"
       run_test_command("test/helpers").tap do |output|
         assert_match "FooHelperTest", output
         assert_match "BarHelperTest", output
@@ -60,12 +86,12 @@ module ApplicationTests
     end
 
     def test_run_units
-      skip "we no longer have the concept of unit tests. Just different directories..."
-      create_test_file :models, 'foo'
-      create_test_file :helpers, 'bar_helper'
-      create_test_file :unit, 'baz_unit'
-      create_test_file :controllers, 'foobar_controller'
-      run_test_units_command.tap do |output|
+      create_test_file :models, "foo"
+      create_test_file :helpers, "bar_helper"
+      create_test_file :unit, "baz_unit"
+      create_test_file :controllers, "foobar_controller"
+
+      rails("test:units").tap do |output|
         assert_match "FooTest", output
         assert_match "BarHelperTest", output
         assert_match "BazUnitTest", output
@@ -74,9 +100,9 @@ module ApplicationTests
     end
 
     def test_run_controllers
-      create_test_file :controllers, 'foo_controller'
-      create_test_file :controllers, 'bar_controller'
-      create_test_file :models, 'foo'
+      create_test_file :controllers, "foo_controller"
+      create_test_file :controllers, "bar_controller"
+      create_test_file :models, "foo"
       run_test_command("test/controllers").tap do |output|
         assert_match "FooControllerTest", output
         assert_match "BarControllerTest", output
@@ -85,9 +111,9 @@ module ApplicationTests
     end
 
     def test_run_mailers
-      create_test_file :mailers, 'foo_mailer'
-      create_test_file :mailers, 'bar_mailer'
-      create_test_file :models, 'foo'
+      create_test_file :mailers, "foo_mailer"
+      create_test_file :mailers, "bar_mailer"
+      create_test_file :models, "foo"
       run_test_command("test/mailers").tap do |output|
         assert_match "FooMailerTest", output
         assert_match "BarMailerTest", output
@@ -96,9 +122,9 @@ module ApplicationTests
     end
 
     def test_run_jobs
-      create_test_file :jobs, 'foo_job'
-      create_test_file :jobs, 'bar_job'
-      create_test_file :models, 'foo'
+      create_test_file :jobs, "foo_job"
+      create_test_file :jobs, "bar_job"
+      create_test_file :models, "foo"
       run_test_command("test/jobs").tap do |output|
         assert_match "FooJobTest", output
         assert_match "BarJobTest", output
@@ -107,12 +133,12 @@ module ApplicationTests
     end
 
     def test_run_functionals
-      skip "we no longer have the concept of functional tests. Just different directories..."
-      create_test_file :mailers, 'foo_mailer'
-      create_test_file :controllers, 'bar_controller'
-      create_test_file :functional, 'baz_functional'
-      create_test_file :models, 'foo'
-      run_test_functionals_command.tap do |output|
+      create_test_file :mailers, "foo_mailer"
+      create_test_file :controllers, "bar_controller"
+      create_test_file :functional, "baz_functional"
+      create_test_file :models, "foo"
+
+      rails("test:functionals").tap do |output|
         assert_match "FooMailerTest", output
         assert_match "BarControllerTest", output
         assert_match "BazFunctionalTest", output
@@ -121,8 +147,8 @@ module ApplicationTests
     end
 
     def test_run_integration
-      create_test_file :integration, 'foo_integration'
-      create_test_file :models, 'foo'
+      create_test_file :integration, "foo_integration"
+      create_test_file :models, "foo"
       run_test_command("test/integration").tap do |output|
         assert_match "FooIntegration", output
         assert_match "1 runs, 1 assertions, 0 failures", output
@@ -132,14 +158,14 @@ module ApplicationTests
     def test_run_all_suites
       suites = [:models, :helpers, :unit, :controllers, :mailers, :functional, :integration, :jobs]
       suites.each { |suite| create_test_file suite, "foo_#{suite}" }
-      run_test_command('') .tap do |output|
+      run_test_command("") .tap do |output|
         suites.each { |suite| assert_match "Foo#{suite.to_s.camelize}Test", output }
         assert_match "8 runs, 8 assertions, 0 failures", output
       end
     end
 
     def test_run_named_test
-      app_file 'test/unit/chu_2_koi_test.rb', <<-RUBY
+      app_file "test/unit/chu_2_koi_test.rb", <<-RUBY
         require 'test_helper'
 
         class Chu2KoiTest < ActiveSupport::TestCase
@@ -153,14 +179,14 @@ module ApplicationTests
         end
       RUBY
 
-      run_test_command('-n test_rikka test/unit/chu_2_koi_test.rb').tap do |output|
+      run_test_command("-n test_rikka test/unit/chu_2_koi_test.rb").tap do |output|
         assert_match "Rikka", output
         assert_no_match "Sanae", output
       end
     end
 
     def test_run_matched_test
-      app_file 'test/unit/chu_2_koi_test.rb', <<-RUBY
+      app_file "test/unit/chu_2_koi_test.rb", <<-RUBY
         require 'test_helper'
 
         class Chu2KoiTest < ActiveSupport::TestCase
@@ -174,7 +200,7 @@ module ApplicationTests
         end
       RUBY
 
-      run_test_command('-n /rikka/ test/unit/chu_2_koi_test.rb').tap do |output|
+      run_test_command("-n /rikka/ test/unit/chu_2_koi_test.rb").tap do |output|
         assert_match "Rikka", output
         assert_no_match "Sanae", output
       end
@@ -195,14 +221,14 @@ module ApplicationTests
     def test_run_with_model
       skip "These feel a bit odd. Not sure we should keep supporting them."
       create_model_with_fixture
-      create_fixture_test 'models', 'user'
+      create_fixture_test "models", "user"
       assert_match "3 users", run_task(["test models/user"])
       assert_match "3 users", run_task(["test app/models/user.rb"])
     end
 
     def test_run_different_environment_using_env_var
       skip "no longer possible. Running tests in a different environment should be explicit"
-      app_file 'test/unit/env_test.rb', <<-RUBY
+      app_file "test/unit/env_test.rb", <<-RUBY
         require 'test_helper'
 
         class EnvTest < ActiveSupport::TestCase
@@ -212,14 +238,14 @@ module ApplicationTests
         end
       RUBY
 
-      ENV['RAILS_ENV'] = 'development'
-      assert_match "development", run_test_command('test/unit/env_test.rb')
+      ENV["RAILS_ENV"] = "development"
+      assert_match "development", run_test_command("test/unit/env_test.rb")
     end
 
     def test_run_in_test_environment_by_default
       create_env_test
 
-      assert_match "Current Environment: test", run_test_command('test/unit/env_test.rb')
+      assert_match "Current Environment: test", run_test_command("test/unit/env_test.rb")
     end
 
     def test_run_different_environment
@@ -231,27 +257,39 @@ module ApplicationTests
 
     def test_generated_scaffold_works_with_rails_test
       create_scaffold
-      assert_match "0 failures, 0 errors, 0 skips", run_test_command('')
+      assert_match "0 failures, 0 errors, 0 skips", run_test_command("")
     end
 
     def test_generated_controller_works_with_rails_test
       create_controller
-      assert_match "0 failures, 0 errors, 0 skips", run_test_command('')
+      assert_match "0 failures, 0 errors, 0 skips", run_test_command("")
     end
 
     def test_run_multiple_folders
-      create_test_file :models, 'account'
-      create_test_file :controllers, 'accounts_controller'
+      create_test_file :models, "account"
+      create_test_file :controllers, "accounts_controller"
+
+      run_test_command("test/models test/controllers").tap do |output|
+        assert_match "AccountTest", output
+        assert_match "AccountsControllerTest", output
+        assert_match "2 runs, 2 assertions, 0 failures, 0 errors, 0 skips", output
+      end
+    end
 
-      run_test_command('test/models test/controllers').tap do |output|
-        assert_match 'AccountTest', output
-        assert_match 'AccountsControllerTest', output
-        assert_match '2 runs, 2 assertions, 0 failures, 0 errors, 0 skips', output
+    def test_run_multiple_folders_with_absolute_paths
+      create_test_file :models, "account"
+      create_test_file :controllers, "accounts_controller"
+      create_test_file :helpers, "foo_helper"
+
+      run_test_command("#{app_path}/test/models #{app_path}/test/controllers").tap do |output|
+        assert_match "AccountTest", output
+        assert_match "AccountsControllerTest", output
+        assert_match "2 runs, 2 assertions, 0 failures, 0 errors, 0 skips", output
       end
     end
 
     def test_run_with_ruby_command
-      app_file 'test/models/post_test.rb', <<-RUBY
+      app_file "test/models/post_test.rb", <<-RUBY
         require 'test_helper'
 
         class PostTest < ActiveSupport::TestCase
@@ -264,15 +302,15 @@ module ApplicationTests
 
       Dir.chdir(app_path) do
         `ruby -Itest test/models/post_test.rb`.tap do |output|
-          assert_match 'PostTest', output
-          assert_no_match 'is already defined in', output
+          assert_match "PostTest", output
+          assert_no_match "is already defined in", output
         end
       end
     end
 
     def test_mix_files_and_line_filters
-      create_test_file :models, 'account'
-      app_file 'test/models/post_test.rb', <<-RUBY
+      create_test_file :models, "account"
+      app_file "test/models/post_test.rb", <<-RUBY
         require 'test_helper'
 
         class PostTest < ActiveSupport::TestCase
@@ -287,15 +325,15 @@ module ApplicationTests
         end
       RUBY
 
-      run_test_command('test/models/account_test.rb test/models/post_test.rb:4').tap do |output|
-        assert_match 'AccountTest', output
-        assert_match 'PostTest', output
-        assert_match '2 runs, 2 assertions', output
+      run_test_command("test/models/account_test.rb test/models/post_test.rb:4").tap do |output|
+        assert_match "AccountTest", output
+        assert_match "PostTest", output
+        assert_match "2 runs, 2 assertions", output
       end
     end
 
     def test_more_than_one_line_filter
-      app_file 'test/models/post_test.rb', <<-RUBY
+      app_file "test/models/post_test.rb", <<-RUBY
         require 'test_helper'
 
         class PostTest < ActiveSupport::TestCase
@@ -309,21 +347,21 @@ module ApplicationTests
             assert true
           end
 
-          test "test line filter does not run this" do
+          test "line filter does not run this" do
             assert true
           end
         end
       RUBY
 
-      run_test_command('test/models/post_test.rb:4:9').tap do |output|
-        assert_match 'PostTest:FirstFilter', output
-        assert_match 'PostTest:SecondFilter', output
-        assert_match '2 runs, 2 assertions', output
+      run_test_command("test/models/post_test.rb:4:9").tap do |output|
+        assert_match "PostTest:FirstFilter", output
+        assert_match "PostTest:SecondFilter", output
+        assert_match "2 runs, 2 assertions", output
       end
     end
 
     def test_more_than_one_line_filter_with_multiple_files
-      app_file 'test/models/account_test.rb', <<-RUBY
+      app_file "test/models/account_test.rb", <<-RUBY
         require 'test_helper'
 
         class AccountTest < ActiveSupport::TestCase
@@ -343,7 +381,7 @@ module ApplicationTests
         end
       RUBY
 
-      app_file 'test/models/post_test.rb', <<-RUBY
+      app_file "test/models/post_test.rb", <<-RUBY
         require 'test_helper'
 
         class PostTest < ActiveSupport::TestCase
@@ -363,27 +401,27 @@ module ApplicationTests
         end
       RUBY
 
-      run_test_command('test/models/account_test.rb:4:9 test/models/post_test.rb:4:9').tap do |output|
-        assert_match 'AccountTest:FirstFilter', output
-        assert_match 'AccountTest:SecondFilter', output
-        assert_match 'PostTest:FirstFilter', output
-        assert_match 'PostTest:SecondFilter', output
-        assert_match '4 runs, 4 assertions', output
+      run_test_command("test/models/account_test.rb:4:9 test/models/post_test.rb:4:9").tap do |output|
+        assert_match "AccountTest:FirstFilter", output
+        assert_match "AccountTest:SecondFilter", output
+        assert_match "PostTest:FirstFilter", output
+        assert_match "PostTest:SecondFilter", output
+        assert_match "4 runs, 4 assertions", output
       end
     end
 
     def test_multiple_line_filters
-      create_test_file :models, 'account'
-      create_test_file :models, 'post'
+      create_test_file :models, "account"
+      create_test_file :models, "post"
 
-      run_test_command('test/models/account_test.rb:4 test/models/post_test.rb:4').tap do |output|
-        assert_match 'AccountTest', output
-        assert_match 'PostTest', output
+      run_test_command("test/models/account_test.rb:4 test/models/post_test.rb:4").tap do |output|
+        assert_match "AccountTest", output
+        assert_match "PostTest", output
       end
     end
 
     def test_line_filters_trigger_only_one_runnable
-      app_file 'test/models/post_test.rb', <<-RUBY
+      app_file "test/models/post_test.rb", <<-RUBY
         require 'test_helper'
 
         class PostTest < ActiveSupport::TestCase
@@ -400,14 +438,14 @@ module ApplicationTests
       RUBY
 
       # Pass seed guaranteeing failure.
-      run_test_command('test/models/post_test.rb:4 --seed 30410').tap do |output|
-        assert_no_match 'ran second runnable', output
-        assert_match '1 runs, 1 assertions', output
+      run_test_command("test/models/post_test.rb:4 --seed 30410").tap do |output|
+        assert_no_match "ran second runnable", output
+        assert_match "1 runs, 1 assertions", output
       end
     end
 
     def test_line_filter_with_minitest_string_filter
-      app_file 'test/models/post_test.rb', <<-RUBY
+      app_file "test/models/post_test.rb", <<-RUBY
         require 'test_helper'
 
         class PostTest < ActiveSupport::TestCase
@@ -423,128 +461,264 @@ module ApplicationTests
         end
       RUBY
 
-      run_test_command('test/models/post_test.rb:4 -n test_by_name').tap do |output|
-        assert_match 'by line', output
-        assert_match 'by name', output
-        assert_match '2 runs, 2 assertions', output
+      run_test_command("test/models/post_test.rb:4 -n test_by_name").tap do |output|
+        assert_match "by line", output
+        assert_match "by name", output
+        assert_match "2 runs, 2 assertions", output
       end
     end
 
     def test_shows_filtered_backtrace_by_default
       create_backtrace_test
 
-      assert_match 'Rails::BacktraceCleaner', run_test_command('test/unit/backtrace_test.rb')
+      assert_match "Rails::BacktraceCleaner", run_test_command("test/unit/backtrace_test.rb")
     end
 
     def test_backtrace_option
       create_backtrace_test
 
-      assert_match 'Minitest::BacktraceFilter', run_test_command('test/unit/backtrace_test.rb -b')
-      assert_match 'Minitest::BacktraceFilter',
-        run_test_command('test/unit/backtrace_test.rb --backtrace')
+      assert_match "Minitest::BacktraceFilter", run_test_command("test/unit/backtrace_test.rb -b")
+      assert_match "Minitest::BacktraceFilter",
+        run_test_command("test/unit/backtrace_test.rb --backtrace")
     end
 
     def test_show_full_backtrace_using_backtrace_environment_variable
       create_backtrace_test
 
-      switch_env 'BACKTRACE', 'true' do
-        assert_match 'Minitest::BacktraceFilter', run_test_command('test/unit/backtrace_test.rb')
+      switch_env "BACKTRACE", "true" do
+        assert_match "Minitest::BacktraceFilter", run_test_command("test/unit/backtrace_test.rb")
       end
     end
 
     def test_run_app_without_rails_loaded
       # Simulate a real Rails app boot.
-      app_file 'config/boot.rb', <<-RUBY
-        ENV['BUNDLE_GEMFILE'] ||= File.expand_path('../../Gemfile', __FILE__)
+      app_file "config/boot.rb", <<-RUBY
+        ENV['BUNDLE_GEMFILE'] ||= File.expand_path('../Gemfile', __dir__)
 
         require 'bundler/setup' # Set up gems listed in the Gemfile.
       RUBY
 
-      assert_match '0 runs, 0 assertions', run_test_command('')
+      assert_match "0 runs, 0 assertions", run_test_command("")
     end
 
     def test_output_inline_by_default
-      create_test_file :models, 'post', pass: false
+      create_test_file :models, "post", pass: false
 
-      output = run_test_command('test/models/post_test.rb')
+      output = run_test_command("test/models/post_test.rb")
       expect = %r{Running:\n\nPostTest\nF\n\nFailure:\nPostTest#test_truth \[[^\]]+test/models/post_test.rb:6\]:\nwups!\n\nbin/rails test test/models/post_test.rb:4\n\n\n\n}
       assert_match expect, output
     end
 
     def test_only_inline_failure_output
-      create_test_file :models, 'post', pass: false
+      create_test_file :models, "post", pass: false
 
-      output = run_test_command('test/models/post_test.rb')
-      assert_match %r{Finished in.*\n\n1 runs, 1 assertions}, output
+      output = run_test_command("test/models/post_test.rb")
+      assert_match %r{Finished in.*\n1 runs, 1 assertions}, output
     end
 
     def test_fail_fast
-      create_test_file :models, 'post', pass: false
+      create_test_file :models, "post", pass: false
 
       assert_match(/Interrupt/,
-        capture(:stderr) { run_test_command('test/models/post_test.rb --fail-fast') })
+        capture(:stderr) { run_test_command("test/models/post_test.rb --fail-fast", stderr: true) })
     end
 
     def test_raise_error_when_specified_file_does_not_exist
-      error = capture(:stderr) { run_test_command('test/not_exists.rb') }
+      error = capture(:stderr) { run_test_command("test/not_exists.rb", stderr: true) }
       assert_match(%r{cannot load such file.+test/not_exists\.rb}, error)
     end
 
     def test_pass_TEST_env_on_rake_test
-      create_test_file :models, 'account'
-      create_test_file :models, 'post', pass: false
+      create_test_file :models, "account"
+      create_test_file :models, "post", pass: false
       # This specifically verifies TEST for backwards compatibility with rake test
       # as bin/rails test already supports running tests from a single file more cleanly.
-      output =  Dir.chdir(app_path) { `bin/rake test TEST=test/models/post_test.rb` }
+      output = Dir.chdir(app_path) { `bin/rake test TEST=test/models/post_test.rb` }
 
       assert_match "PostTest", output, "passing TEST= should run selected test"
       assert_no_match "AccountTest", output, "passing TEST= should only run selected test"
-      assert_match '1 runs, 1 assertions', output
+      assert_match "1 runs, 1 assertions", output
     end
 
     def test_pass_rake_options
-      create_test_file :models, 'account'
-      output =  Dir.chdir(app_path) { `bin/rake --rakefile Rakefile --trace=stdout test` }
+      create_test_file :models, "account"
+      output = Dir.chdir(app_path) { `bin/rake --rakefile Rakefile --trace=stdout test` }
 
-      assert_match '1 runs, 1 assertions', output
-      assert_match 'Execute test', output
+      assert_match "1 runs, 1 assertions", output
+      assert_match "Execute test", output
     end
 
     def test_rails_db_create_all_restores_db_connection
-      create_test_file :models, 'account'
-      output =  Dir.chdir(app_path) { `bin/rails db:create:all db:migrate && echo ".tables" | rails dbconsole` }
+      create_test_file :models, "account"
+      rails "db:create:all", "db:migrate"
+      output = Dir.chdir(app_path) { `echo ".tables" | rails dbconsole` }
       assert_match "ar_internal_metadata", output, "tables should be dumped"
     end
 
     def test_rails_db_create_all_restores_db_connection_after_drop
-      create_test_file :models, 'account'
-      Dir.chdir(app_path) { `bin/rails db:create:all` } # create all to avoid warnings
-      output =  Dir.chdir(app_path) { `bin/rails db:drop:all db:create:all db:migrate && echo ".tables" | rails dbconsole` }
+      create_test_file :models, "account"
+      rails "db:create:all" # create all to avoid warnings
+      rails "db:drop:all", "db:create:all", "db:migrate"
+      output = Dir.chdir(app_path) { `echo ".tables" | rails dbconsole` }
       assert_match "ar_internal_metadata", output, "tables should be dumped"
     end
 
     def test_rake_passes_TESTOPTS_to_minitest
-      create_test_file :models, 'account'
-      output =  Dir.chdir(app_path) { `bin/rake test TESTOPTS=-v` }
+      create_test_file :models, "account"
+      output = Dir.chdir(app_path) { `bin/rake test TESTOPTS=-v` }
       assert_match "AccountTest#test_truth", output, "passing TEST= should run selected test"
     end
 
+    def test_running_with_ruby_gets_test_env_by_default
+      # Subshells inherit `ENV`, so we need to ensure `RAILS_ENV` is set to
+      # nil before we run the tests in the test app.
+      re, ENV["RAILS_ENV"] = ENV["RAILS_ENV"], nil
+
+      file = create_test_for_env("test")
+      results = Dir.chdir(app_path) {
+        `ruby -Ilib:test #{file}`.each_line.map { |line| JSON.parse line }
+      }
+      assert_equal 1, results.length
+      failures = results.first["failures"]
+      flunk(failures.first) unless failures.empty?
+
+    ensure
+      ENV["RAILS_ENV"] = re
+    end
+
+    def test_running_with_ruby_can_set_env_via_cmdline
+      # Subshells inherit `ENV`, so we need to ensure `RAILS_ENV` is set to
+      # nil before we run the tests in the test app.
+      re, ENV["RAILS_ENV"] = ENV["RAILS_ENV"], nil
+
+      file = create_test_for_env("development")
+      results = Dir.chdir(app_path) {
+        `RAILS_ENV=development ruby -Ilib:test #{file}`.each_line.map { |line| JSON.parse line }
+      }
+      assert_equal 1, results.length
+      failures = results.first["failures"]
+      flunk(failures.first) unless failures.empty?
+
+    ensure
+      ENV["RAILS_ENV"] = re
+    end
+
     def test_rake_passes_multiple_TESTOPTS_to_minitest
-      create_test_file :models, 'account'
-      output =  Dir.chdir(app_path) { `bin/rake test TESTOPTS='-v --seed=1234'` }
+      create_test_file :models, "account"
+      output = Dir.chdir(app_path) { `bin/rake test TESTOPTS='-v --seed=1234'` }
       assert_match "AccountTest#test_truth", output, "passing TEST= should run selected test"
       assert_match "seed=1234", output, "passing TEST= should run selected test"
     end
 
+    def test_rake_runs_multiple_test_tasks
+      create_test_file :models, "account"
+      create_test_file :controllers, "accounts_controller"
+      output = Dir.chdir(app_path) { `bin/rake test:models test:controllers TESTOPTS='-v'` }
+      assert_match "AccountTest#test_truth", output
+      assert_match "AccountsControllerTest#test_truth", output
+    end
+
+    def test_rake_db_and_test_tasks_parses_args_correctly
+      create_test_file :models, "account"
+      output = Dir.chdir(app_path) { `bin/rake db:migrate test:models TESTOPTS='-v' && echo ".tables" | rails dbconsole` }
+      assert_match "AccountTest#test_truth", output
+      assert_match "ar_internal_metadata", output
+    end
+
+    def test_warnings_option
+      app_file "test/models/warnings_test.rb", <<-RUBY
+        require 'test_helper'
+        def test_warnings
+          a = 1
+        end
+      RUBY
+      assert_match(/warning: assigned but unused variable/,
+        capture(:stderr) { run_test_command("test/models/warnings_test.rb -w", stderr: true) })
+    end
+
+    def test_reset_sessions_before_rollback_on_system_tests
+      app_file "test/system/reset_session_before_rollback_test.rb", <<-RUBY
+        require "application_system_test_case"
+
+        class ResetSessionBeforeRollbackTest < ApplicationSystemTestCase
+          def teardown_fixtures
+            puts "rollback"
+            super
+          end
+
+          Capybara.singleton_class.prepend(Module.new do
+            def reset_sessions!
+              puts "reset sessions"
+              super
+            end
+          end)
+
+          test "dummy" do
+          end
+        end
+      RUBY
+
+      run_test_command("test/system/reset_session_before_rollback_test.rb").tap do |output|
+        assert_match "reset sessions\nrollback", output
+        assert_match "1 runs, 0 assertions, 0 failures, 0 errors, 0 skips", output
+      end
+    end
+
+    def test_system_tests_are_not_run_with_the_default_test_command
+      app_file "test/system/dummy_test.rb", <<-RUBY
+        require "application_system_test_case"
+
+        class DummyTest < ApplicationSystemTestCase
+          test "something" do
+            assert true
+          end
+        end
+      RUBY
+
+      run_test_command("").tap do |output|
+        assert_match "0 runs, 0 assertions, 0 failures, 0 errors, 0 skips", output
+      end
+    end
+
+    def test_system_tests_are_not_run_through_rake_test
+      app_file "test/system/dummy_test.rb", <<-RUBY
+        require "application_system_test_case"
+
+        class DummyTest < ApplicationSystemTestCase
+          test "something" do
+            assert true
+          end
+        end
+      RUBY
+
+      output = Dir.chdir(app_path) { `bin/rake test` }
+      assert_match "0 runs, 0 assertions, 0 failures, 0 errors, 0 skips", output
+    end
+
+    def test_system_tests_are_run_through_rake_test_when_given_in_TEST
+      app_file "test/system/dummy_test.rb", <<-RUBY
+        require "application_system_test_case"
+
+        class DummyTest < ApplicationSystemTestCase
+          test "something" do
+            assert true
+          end
+        end
+      RUBY
+
+      output = Dir.chdir(app_path) { `bin/rake test TEST=test/system/dummy_test.rb` }
+      assert_match "1 runs, 1 assertions, 0 failures, 0 errors, 0 skips", output
+    end
+
     private
-      def run_test_command(arguments = 'test/unit/test_test.rb')
-        Dir.chdir(app_path) { `bin/rails t #{arguments}` }
+      def run_test_command(arguments = "test/unit/test_test.rb", **opts)
+        rails "t", *Shellwords.split(arguments), allow_failure: true, **opts
       end
 
       def create_model_with_fixture
-        script 'generate model user name:string'
+        rails "generate", "model", "user", "name:string"
 
-        app_file 'test/fixtures/users.yml', <<-YAML.strip_heredoc
+        app_file "test/fixtures/users.yml", <<-YAML.strip_heredoc
           vampire:
             id: 1
             name: Koyomi Araragi
@@ -559,7 +733,7 @@ module ApplicationTests
         run_migration
       end
 
-      def create_fixture_test(path = :unit, name = 'test')
+      def create_fixture_test(path = :unit, name = "test")
         app_file "test/#{path}/#{name}_test.rb", <<-RUBY
           require 'test_helper'
 
@@ -572,7 +746,7 @@ module ApplicationTests
       end
 
       def create_backtrace_test
-        app_file 'test/unit/backtrace_test.rb', <<-RUBY
+        app_file "test/unit/backtrace_test.rb", <<-RUBY
           require 'test_helper'
 
           class BacktraceTest < ActiveSupport::TestCase
@@ -584,10 +758,49 @@ module ApplicationTests
       end
 
       def create_schema
-        app_file 'db/schema.rb', ''
+        app_file "db/schema.rb", ""
+      end
+
+      def create_test_for_env(env)
+        app_file "test/models/environment_test.rb", <<-RUBY
+          require 'test_helper'
+          class JSONReporter < Minitest::AbstractReporter
+            def record(result)
+              puts JSON.dump(klass: result.class.name,
+                             name: result.name,
+                             failures: result.failures,
+                             assertions: result.assertions,
+                             time: result.time)
+            end
+          end
+
+          def Minitest.plugin_json_reporter_init(opts)
+            Minitest.reporter.reporters.clear
+            Minitest.reporter.reporters << JSONReporter.new
+          end
+
+          Minitest.extensions << "rails"
+          Minitest.extensions << "json_reporter"
+
+          # Minitest uses RubyGems to find plugins, and since RubyGems
+          # doesn't know about the Rails installation we're pointing at,
+          # Minitest won't require the Rails minitest plugin when we run
+          # these integration tests.  So we have to manually require the
+          # Minitest plugin here.
+          require 'minitest/rails_plugin'
+
+          class EnvironmentTest < ActiveSupport::TestCase
+            def test_environment
+              test_db = ActiveRecord::Base.configurations[#{env.dump}]["database"]
+              db_file = ActiveRecord::Base.connection_config[:database]
+              assert_match(test_db, db_file)
+              assert_equal #{env.dump}, ENV["RAILS_ENV"]
+            end
+          end
+        RUBY
       end
 
-      def create_test_file(path = :unit, name = 'test', pass: true)
+      def create_test_file(path = :unit, name = "test", pass: true)
         app_file "test/#{path}/#{name}_test.rb", <<-RUBY
           require 'test_helper'
 
@@ -601,7 +814,7 @@ module ApplicationTests
       end
 
       def create_env_test
-        app_file 'test/unit/env_test.rb', <<-RUBY
+        app_file "test/unit/env_test.rb", <<-RUBY
           require 'test_helper'
 
           class EnvTest < ActiveSupport::TestCase
@@ -613,17 +826,17 @@ module ApplicationTests
       end
 
       def create_scaffold
-        script 'generate scaffold user name:string'
-        Dir.chdir(app_path) { File.exist?('app/models/user.rb') }
+        rails "generate", "scaffold", "user", "name:string"
+        assert File.exist?("#{app_path}/app/models/user.rb")
         run_migration
       end
 
       def create_controller
-        script 'generate controller admin/dashboard index'
+        rails "generate", "controller", "admin/dashboard", "index"
       end
 
       def run_migration
-        Dir.chdir(app_path) { `bin/rails db:migrate` }
+        rails "db:migrate"
       end
   end
 end
diff --git a/railties/test/application/test_test.rb b/railties/test/application/test_test.rb
index 85b003fce9..0a51e98656 100644
--- a/railties/test/application/test_test.rb
+++ b/railties/test/application/test_test.rb
@@ -1,4 +1,6 @@
-require 'isolation/abstract_unit'
+# frozen_string_literal: true
+
+require "isolation/abstract_unit"
 
 module ApplicationTests
   class TestTest < ActiveSupport::TestCase
@@ -6,15 +8,14 @@ module ApplicationTests
 
     def setup
       build_app
-      boot_rails
     end
 
     def teardown
       teardown_app
     end
 
-    test "truth" do
-      app_file 'test/unit/foo_test.rb', <<-RUBY
+    test "simple successful test" do
+      app_file "test/unit/foo_test.rb", <<-RUBY
         require 'test_helper'
 
         class FooTest < ActiveSupport::TestCase
@@ -24,20 +25,52 @@ module ApplicationTests
         end
       RUBY
 
-      assert_successful_test_run 'unit/foo_test.rb'
+      assert_successful_test_run "unit/foo_test.rb"
+    end
+
+    test "after_run" do
+      app_file "test/unit/foo_test.rb", <<-RUBY
+        require 'test_helper'
+
+        Minitest.after_run { puts "WORLD" }
+        Minitest.after_run { puts "HELLO" }
+
+        class FooTest < ActiveSupport::TestCase
+          def test_truth
+            assert true
+          end
+        end
+      RUBY
+
+      result = assert_successful_test_run "unit/foo_test.rb"
+      assert_equal ["HELLO", "WORLD"], result.scan(/HELLO|WORLD/) # only once and in correct order
+    end
+
+    test "simple failed test" do
+      app_file "test/unit/foo_test.rb", <<-RUBY
+        require 'test_helper'
+
+        class FooTest < ActiveSupport::TestCase
+          def test_truth
+            assert false
+          end
+        end
+      RUBY
+
+      assert_unsuccessful_run "unit/foo_test.rb", "Failure:\nFooTest#test_truth"
     end
 
     test "integration test" do
-      controller 'posts', <<-RUBY
+      controller "posts", <<-RUBY
         class PostsController < ActionController::Base
         end
       RUBY
 
-      app_file 'app/views/posts/index.html.erb', <<-HTML
+      app_file "app/views/posts/index.html.erb", <<-HTML
         Posts#index
       HTML
 
-      app_file 'test/integration/posts_test.rb', <<-RUBY
+      app_file "test/integration/posts_test.rb", <<-RUBY
         require 'test_helper'
 
         class PostsTest < ActionDispatch::IntegrationTest
@@ -49,11 +82,11 @@ module ApplicationTests
         end
       RUBY
 
-      assert_successful_test_run 'integration/posts_test.rb'
+      assert_successful_test_run "integration/posts_test.rb"
     end
 
     test "enable full backtraces on test failures" do
-      app_file 'test/unit/failing_test.rb', <<-RUBY
+      app_file "test/unit/failing_test.rb", <<-RUBY
         require 'test_helper'
 
         class FailingTest < ActiveSupport::TestCase
@@ -63,16 +96,16 @@ module ApplicationTests
         end
       RUBY
 
-      output = run_test_file('unit/failing_test.rb', env: { "BACKTRACE" => "1" })
+      output = run_test_file("unit/failing_test.rb", env: { "BACKTRACE" => "1" })
       assert_match %r{test/unit/failing_test\.rb}, output
       assert_match %r{test/unit/failing_test\.rb:4}, output
     end
 
     test "ruby schema migrations" do
-      output  = script('generate model user name:string')
+      output  = rails("generate", "model", "user", "name:string")
       version = output.match(/(\d+)_create_users\.rb/)[1]
 
-      app_file 'test/models/user_test.rb', <<-RUBY
+      app_file "test/models/user_test.rb", <<-RUBY
         require 'test_helper'
 
         class UserTest < ActiveSupport::TestCase
@@ -81,11 +114,11 @@ module ApplicationTests
           end
         end
       RUBY
-      app_file 'db/schema.rb', ''
+      app_file "db/schema.rb", ""
 
       assert_unsuccessful_run "models/user_test.rb", "Migrations are pending"
 
-      app_file 'db/schema.rb', <<-RUBY
+      app_file "db/schema.rb", <<-RUBY
         ActiveRecord::Schema.define(version: #{version}) do
           create_table :users do |t|
             t.string :name
@@ -93,7 +126,7 @@ module ApplicationTests
         end
       RUBY
 
-      app_file 'config/initializers/disable_maintain_test_schema.rb', <<-RUBY
+      app_file "config/initializers/disable_maintain_test_schema.rb", <<-RUBY
         Rails.application.config.active_record.maintain_test_schema = false
       RUBY
 
@@ -101,15 +134,15 @@ module ApplicationTests
 
       File.delete "#{app_path}/config/initializers/disable_maintain_test_schema.rb"
 
-      result = assert_successful_test_run('models/user_test.rb')
-      assert !result.include?("create_table(:users)")
+      result = assert_successful_test_run("models/user_test.rb")
+      assert_not_includes result, "create_table(:users)"
     end
 
     test "sql structure migrations" do
-      output  = script('generate model user name:string')
+      output  = rails("generate", "model", "user", "name:string")
       version = output.match(/(\d+)_create_users\.rb/)[1]
 
-      app_file 'test/models/user_test.rb', <<-RUBY
+      app_file "test/models/user_test.rb", <<-RUBY
         require 'test_helper'
 
         class UserTest < ActiveSupport::TestCase
@@ -119,21 +152,21 @@ module ApplicationTests
         end
       RUBY
 
-      app_file 'db/structure.sql', ''
-      app_file 'config/initializers/enable_sql_schema_format.rb', <<-RUBY
+      app_file "db/structure.sql", ""
+      app_file "config/initializers/enable_sql_schema_format.rb", <<-RUBY
         Rails.application.config.active_record.schema_format = :sql
       RUBY
 
       assert_unsuccessful_run "models/user_test.rb", "Migrations are pending"
 
-      app_file 'db/structure.sql', <<-SQL
+      app_file "db/structure.sql", <<-SQL
         CREATE TABLE "schema_migrations" ("version" varchar(255) NOT NULL);
         CREATE UNIQUE INDEX "unique_schema_migrations" ON "schema_migrations" ("version");
         CREATE TABLE "users" ("id" INTEGER PRIMARY KEY AUTOINCREMENT NOT NULL, "name" varchar(255));
         INSERT INTO schema_migrations (version) VALUES ('#{version}');
       SQL
 
-      app_file 'config/initializers/disable_maintain_test_schema.rb', <<-RUBY
+      app_file "config/initializers/disable_maintain_test_schema.rb", <<-RUBY
         Rails.application.config.active_record.maintain_test_schema = false
       RUBY
 
@@ -141,14 +174,14 @@ module ApplicationTests
 
       File.delete "#{app_path}/config/initializers/disable_maintain_test_schema.rb"
 
-      assert_successful_test_run('models/user_test.rb')
+      assert_successful_test_run("models/user_test.rb")
     end
 
     test "sql structure migrations when adding column to existing table" do
-      output_1  = script('generate model user name:string')
+      output_1  = rails("generate", "model", "user", "name:string")
       version_1 = output_1.match(/(\d+)_create_users\.rb/)[1]
 
-      app_file 'test/models/user_test.rb', <<-RUBY
+      app_file "test/models/user_test.rb", <<-RUBY
         require 'test_helper'
         class UserTest < ActiveSupport::TestCase
           test "user" do
@@ -157,23 +190,23 @@ module ApplicationTests
         end
       RUBY
 
-      app_file 'config/initializers/enable_sql_schema_format.rb', <<-RUBY
+      app_file "config/initializers/enable_sql_schema_format.rb", <<-RUBY
         Rails.application.config.active_record.schema_format = :sql
       RUBY
 
-      app_file 'db/structure.sql', <<-SQL
+      app_file "db/structure.sql", <<-SQL
         CREATE TABLE "schema_migrations" ("version" varchar(255) NOT NULL);
         CREATE UNIQUE INDEX "unique_schema_migrations" ON "schema_migrations" ("version");
         CREATE TABLE "users" ("id" INTEGER PRIMARY KEY AUTOINCREMENT NOT NULL, "name" varchar(255));
         INSERT INTO schema_migrations (version) VALUES ('#{version_1}');
       SQL
 
-      assert_successful_test_run('models/user_test.rb')
+      assert_successful_test_run("models/user_test.rb")
 
-      output_2  = script('generate migration add_email_to_users')
+      output_2  = rails("generate", "migration", "add_email_to_users")
       version_2 = output_2.match(/(\d+)_add_email_to_users\.rb/)[1]
 
-      app_file 'test/models/user_test.rb', <<-RUBY
+      app_file "test/models/user_test.rb", <<-RUBY
         require 'test_helper'
 
         class UserTest < ActiveSupport::TestCase
@@ -183,7 +216,7 @@ module ApplicationTests
         end
       RUBY
 
-      app_file 'db/structure.sql', <<-SQL
+      app_file "db/structure.sql", <<-SQL
         CREATE TABLE "schema_migrations" ("version" varchar(255) NOT NULL);
         CREATE UNIQUE INDEX "unique_schema_migrations" ON "schema_migrations" ("version");
         CREATE TABLE "users" ("id" INTEGER PRIMARY KEY AUTOINCREMENT NOT NULL, "name" varchar(255), "email" varchar(255));
@@ -191,17 +224,17 @@ module ApplicationTests
         INSERT INTO schema_migrations (version) VALUES ('#{version_2}');
       SQL
 
-      assert_successful_test_run('models/user_test.rb')
+      assert_successful_test_run("models/user_test.rb")
     end
 
     # TODO: would be nice if we could detect the schema change automatically.
     # For now, the user has to synchronize the schema manually.
     # This test-case serves as a reminder for this use-case.
     test "manually synchronize test schema after rollback" do
-      output  = script('generate model user name:string')
+      output  = rails("generate", "model", "user", "name:string")
       version = output.match(/(\d+)_create_users\.rb/)[1]
 
-      app_file 'test/models/user_test.rb', <<-RUBY
+      app_file "test/models/user_test.rb", <<-RUBY
         require 'test_helper'
 
         class UserTest < ActiveSupport::TestCase
@@ -210,7 +243,7 @@ module ApplicationTests
           end
         end
       RUBY
-      app_file 'db/schema.rb', <<-RUBY
+      app_file "db/schema.rb", <<-RUBY
         ActiveRecord::Schema.define(version: #{version}) do
           create_table :users do |t|
             t.string :name
@@ -221,7 +254,7 @@ module ApplicationTests
       assert_successful_test_run "models/user_test.rb"
 
       # Simulate `db:rollback` + edit of the migration file + `db:migrate`
-      app_file 'db/schema.rb', <<-RUBY
+      app_file "db/schema.rb", <<-RUBY
         ActiveRecord::Schema.define(version: #{version}) do
           create_table :users do |t|
             t.string :name
@@ -232,7 +265,7 @@ module ApplicationTests
 
       assert_successful_test_run "models/user_test.rb"
 
-      Dir.chdir(app_path) { `bin/rails db:test:prepare` }
+      rails "db:test:prepare"
 
       assert_unsuccessful_run "models/user_test.rb", <<-ASSERTION
 Expected: ["id", "name"]
@@ -241,10 +274,10 @@ Expected: ["id", "name"]
     end
 
     test "hooks for plugins" do
-      output  = script('generate model user name:string')
+      output  = rails("generate", "model", "user", "name:string")
       version = output.match(/(\d+)_create_users\.rb/)[1]
 
-      app_file 'lib/tasks/hooks.rake', <<-RUBY
+      app_file "lib/tasks/hooks.rake", <<-RUBY
         task :before_hook do
           has_user_table = ActiveRecord::Base.connection.table_exists?('users')
           puts "before: " + has_user_table.to_s
@@ -259,7 +292,7 @@ Expected: ["id", "name"]
           Rake::Task[:after_hook].invoke
         end
       RUBY
-      app_file 'test/models/user_test.rb', <<-RUBY
+      app_file "test/models/user_test.rb", <<-RUBY
         require 'test_helper'
         class UserTest < ActiveSupport::TestCase
           test "user" do
@@ -269,7 +302,7 @@ Expected: ["id", "name"]
       RUBY
 
       # Simulate `db:migrate`
-      app_file 'db/schema.rb', <<-RUBY
+      app_file "db/schema.rb", <<-RUBY
         ActiveRecord::Schema.define(version: #{version}) do
           create_table :users do |t|
             t.string :name
@@ -290,7 +323,7 @@ Expected: ["id", "name"]
       def assert_unsuccessful_run(name, message)
         result = run_test_file(name)
         assert_not_equal 0, $?.to_i
-        assert result.include?(message)
+        assert_includes result, message
         result
       end
 
@@ -301,7 +334,7 @@ Expected: ["id", "name"]
       end
 
       def run_test_file(name, options = {})
-        Dir.chdir(app_path) { `bin/rails test "#{app_path}/test/#{name}" 2>&1` }
+        rails "test", "#{app_path}/test/#{name}", allow_failure: true
       end
   end
 end
diff --git a/railties/test/application/url_generation_test.rb b/railties/test/application/url_generation_test.rb
index 894e18cb39..f22b9fda3d 100644
--- a/railties/test/application/url_generation_test.rb
+++ b/railties/test/application/url_generation_test.rb
@@ -1,4 +1,6 @@
-require 'isolation/abstract_unit'
+# frozen_string_literal: true
+
+require "isolation/abstract_unit"
 
 module ApplicationTests
   class UrlGenerationTest < ActiveSupport::TestCase
@@ -9,13 +11,11 @@ module ApplicationTests
     end
 
     test "it works" do
-      boot_rails
       require "rails"
       require "action_controller/railtie"
       require "action_view/railtie"
 
       class MyApp < Rails::Application
-        secrets.secret_key_base = "3b7cd727ee24e8444053437c36cc66c4"
         config.session_store :cookie_store, key: "_myapp_session"
         config.active_support.deprecation = :log
         config.eager_load = false
@@ -28,7 +28,7 @@ module ApplicationTests
 
       class ::OmgController < ::ApplicationController
         def index
-          render text: omg_path
+          render plain: omg_path
         end
       end
 
@@ -36,7 +36,7 @@ module ApplicationTests
         get "/" => "omg#index", as: :omg
       end
 
-      require 'rack/test'
+      require "rack/test"
       extend Rack::Test::Methods
 
       get "/"
@@ -44,12 +44,11 @@ module ApplicationTests
     end
 
     def test_routes_know_the_relative_root
-      boot_rails
       require "rails"
       require "action_controller/railtie"
       require "action_view/railtie"
 
-      relative_url = '/hello'
+      relative_url = "/hello"
       ENV["RAILS_RELATIVE_URL_ROOT"] = relative_url
       app = Class.new(Rails::Application)
       assert_equal relative_url, app.routes.relative_url_root
diff --git a/railties/test/application/version_test.rb b/railties/test/application/version_test.rb
new file mode 100644
index 0000000000..ae85cf8f05
--- /dev/null
+++ b/railties/test/application/version_test.rb
@@ -0,0 +1,26 @@
+# frozen_string_literal: true
+
+require "isolation/abstract_unit"
+require "rails/gem_version"
+
+class VersionTest < ActiveSupport::TestCase
+  include ActiveSupport::Testing::Isolation
+
+  def setup
+    build_app
+  end
+
+  def teardown
+    teardown_app
+  end
+
+  test "command works" do
+    output = rails("version")
+    assert_equal "Rails #{Rails.gem_version}\n", output
+  end
+
+  test "short-cut alias works" do
+    output = rails("-v")
+    assert_equal "Rails #{Rails.gem_version}\n", output
+  end
+end
diff --git a/railties/test/backtrace_cleaner_test.rb b/railties/test/backtrace_cleaner_test.rb
index 2dd74f8fd1..70917ba20b 100644
--- a/railties/test/backtrace_cleaner_test.rb
+++ b/railties/test/backtrace_cleaner_test.rb
@@ -1,24 +1,34 @@
-require 'abstract_unit'
-require 'rails/backtrace_cleaner'
+# frozen_string_literal: true
 
-class BacktraceCleanerVendorGemTest < ActiveSupport::TestCase
+require "abstract_unit"
+require "rails/backtrace_cleaner"
+
+class BacktraceCleanerTest < ActiveSupport::TestCase
   def setup
     @cleaner = Rails::BacktraceCleaner.new
   end
 
   test "should format installed gems correctly" do
-    @backtrace = [ "#{Gem.path[0]}/gems/nosuchgem-1.2.3/lib/foo.rb" ]
-    @result = @cleaner.clean(@backtrace, :all)
-    assert_equal "nosuchgem (1.2.3) lib/foo.rb", @result[0]
+    backtrace = [ "#{Gem.path[0]}/gems/nosuchgem-1.2.3/lib/foo.rb" ]
+    result = @cleaner.clean(backtrace, :all)
+    assert_equal "nosuchgem (1.2.3) lib/foo.rb", result[0]
   end
 
   test "should format installed gems not in Gem.default_dir correctly" do
-    @target_dir = Gem.path.detect { |p| p != Gem.default_dir }
+    target_dir = Gem.path.detect { |p| p != Gem.default_dir }
     # skip this test if default_dir is the only directory on Gem.path
-    if @target_dir
-      @backtrace = [ "#{@target_dir}/gems/nosuchgem-1.2.3/lib/foo.rb" ]
-      @result = @cleaner.clean(@backtrace, :all)
-      assert_equal "nosuchgem (1.2.3) lib/foo.rb", @result[0]
+    if target_dir
+      backtrace = [ "#{target_dir}/gems/nosuchgem-1.2.3/lib/foo.rb" ]
+      result = @cleaner.clean(backtrace, :all)
+      assert_equal "nosuchgem (1.2.3) lib/foo.rb", result[0]
     end
   end
+
+  test "should consider traces from irb lines as User code" do
+    backtrace = [ "from (irb):1",
+                  "from /Path/to/rails/railties/lib/rails/commands/console.rb:77:in `start'",
+                  "from bin/rails:4:in `<main>'" ]
+    result = @cleaner.clean(backtrace, :all)
+    assert_equal "from (irb):1", result[0]
+  end
 end
diff --git a/railties/test/code_statistics_calculator_test.rb b/railties/test/code_statistics_calculator_test.rb
index cecc3908b3..51917de2e0 100644
--- a/railties/test/code_statistics_calculator_test.rb
+++ b/railties/test/code_statistics_calculator_test.rb
@@ -1,12 +1,14 @@
-require 'abstract_unit'
-require 'rails/code_statistics_calculator'
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "rails/code_statistics_calculator"
 
 class CodeStatisticsCalculatorTest < ActiveSupport::TestCase
   def setup
     @code_statistics_calculator = CodeStatisticsCalculator.new
   end
 
-  test 'calculate statistics using #add_by_file_path' do
+  test "calculate statistics using #add_by_file_path" do
     code = <<-RUBY
       def foo
         puts 'foo'
@@ -14,7 +16,7 @@ class CodeStatisticsCalculatorTest < ActiveSupport::TestCase
       end
     RUBY
 
-    temp_file 'stats.rb', code do |path|
+    temp_file "stats.rb", code do |path|
       @code_statistics_calculator.add_by_file_path path
 
       assert_equal 4, @code_statistics_calculator.lines
@@ -24,7 +26,7 @@ class CodeStatisticsCalculatorTest < ActiveSupport::TestCase
     end
   end
 
-  test 'count number of methods in MiniTest file' do
+  test "count number of methods in Minitest file" do
     code = <<-RUBY
       class FooTest < ActionController::TestCase
         test 'expectation' do
@@ -37,13 +39,13 @@ class CodeStatisticsCalculatorTest < ActiveSupport::TestCase
       end
     RUBY
 
-    temp_file 'foo_test.rb', code do |path|
+    temp_file "foo_test.rb", code do |path|
       @code_statistics_calculator.add_by_file_path path
       assert_equal 2, @code_statistics_calculator.methods
     end
   end
 
-  test 'add statistics to another using #add' do
+  test "add statistics to another using #add" do
     code_statistics_calculator_1 = CodeStatisticsCalculator.new(1, 2, 3, 4)
     @code_statistics_calculator.add(code_statistics_calculator_1)
 
@@ -52,7 +54,7 @@ class CodeStatisticsCalculatorTest < ActiveSupport::TestCase
     assert_equal 3, @code_statistics_calculator.classes
     assert_equal 4, @code_statistics_calculator.methods
 
-    code_statistics_calculator_2 =  CodeStatisticsCalculator.new(2, 3, 4, 5)
+    code_statistics_calculator_2 = CodeStatisticsCalculator.new(2, 3, 4, 5)
     @code_statistics_calculator.add(code_statistics_calculator_2)
 
     assert_equal 3, @code_statistics_calculator.lines
@@ -61,7 +63,7 @@ class CodeStatisticsCalculatorTest < ActiveSupport::TestCase
     assert_equal 9, @code_statistics_calculator.methods
   end
 
-  test 'accumulate statistics using #add_by_io' do
+  test "accumulate statistics using #add_by_io" do
     code_statistics_calculator_1 = CodeStatisticsCalculator.new(1, 2, 3, 4)
     @code_statistics_calculator.add(code_statistics_calculator_1)
 
@@ -82,7 +84,7 @@ class CodeStatisticsCalculatorTest < ActiveSupport::TestCase
     assert_equal 6, @code_statistics_calculator.methods
   end
 
-  test 'calculate number of Ruby methods' do
+  test "calculate number of Ruby methods" do
     code = <<-'CODE'
       def foo
         puts 'foo'
@@ -101,7 +103,7 @@ class CodeStatisticsCalculatorTest < ActiveSupport::TestCase
     assert_equal 3, @code_statistics_calculator.methods
   end
 
-  test 'calculate Ruby LOCs' do
+  test "calculate Ruby LOCs" do
     code = <<-'CODE'
       def foo
         puts 'foo'
@@ -119,7 +121,7 @@ class CodeStatisticsCalculatorTest < ActiveSupport::TestCase
     assert_equal 5, @code_statistics_calculator.code_lines
   end
 
-  test 'calculate number of Ruby classes' do
+  test "calculate number of Ruby classes" do
     code = <<-'CODE'
       class Foo < Bar
         def foo
@@ -138,7 +140,7 @@ class CodeStatisticsCalculatorTest < ActiveSupport::TestCase
     assert_equal 2, @code_statistics_calculator.classes
   end
 
-  test 'skip Ruby comments' do
+  test "skip Ruby comments" do
     code = <<-'CODE'
 =begin
       class Foo
@@ -160,7 +162,7 @@ class CodeStatisticsCalculatorTest < ActiveSupport::TestCase
     assert_equal 0, @code_statistics_calculator.methods
   end
 
-  test 'calculate number of JS methods' do
+  test "calculate number of JS methods" do
     code = <<-'CODE'
       function foo(x, y, z) {
         doX();
@@ -179,7 +181,7 @@ class CodeStatisticsCalculatorTest < ActiveSupport::TestCase
     assert_equal 3, @code_statistics_calculator.methods
   end
 
-  test 'calculate JS LOCs' do
+  test "calculate JS LOCs" do
     code = <<-'CODE'
       function foo()
         alert('foo');
@@ -196,7 +198,7 @@ class CodeStatisticsCalculatorTest < ActiveSupport::TestCase
     assert_equal 4, @code_statistics_calculator.code_lines
   end
 
-  test 'skip JS comments' do
+  test "skip JS comments" do
     code = <<-'CODE'
       /*
        * var f = function () {
@@ -216,7 +218,7 @@ class CodeStatisticsCalculatorTest < ActiveSupport::TestCase
     assert_equal 0, @code_statistics_calculator.methods
   end
 
-  test 'calculate number of CoffeeScript methods' do
+  test "calculate number of CoffeeScript methods" do
     code = <<-'CODE'
       square = (x) -> x * x
 
@@ -235,7 +237,7 @@ class CodeStatisticsCalculatorTest < ActiveSupport::TestCase
     assert_equal 4, @code_statistics_calculator.methods
   end
 
-  test 'calculate CoffeeScript LOCs' do
+  test "calculate CoffeeScript LOCs" do
     code = <<-'CODE'
       # Assignment:
       number   = 42
@@ -256,7 +258,7 @@ class CodeStatisticsCalculatorTest < ActiveSupport::TestCase
     assert_equal 3, @code_statistics_calculator.code_lines
   end
 
-  test 'calculate number of CoffeeScript classes' do
+  test "calculate number of CoffeeScript classes" do
     code = <<-'CODE'
       class Animal
         constructor: (@name) ->
@@ -277,7 +279,7 @@ class CodeStatisticsCalculatorTest < ActiveSupport::TestCase
     assert_equal 2, @code_statistics_calculator.classes
   end
 
-  test 'skip CoffeeScript comments' do
+  test "skip CoffeeScript comments" do
     code = <<-'CODE'
 ###
 class Animal
@@ -299,7 +301,7 @@ class Animal
     assert_equal 0, @code_statistics_calculator.methods
   end
 
-  test 'count rake tasks' do
+  test "count rake tasks" do
     code = <<-'CODE'
       task :test_task do
         puts 'foo'
@@ -317,7 +319,7 @@ class Animal
 
   private
     def temp_file(name, content)
-      dir = File.expand_path '../fixtures/tmp', __FILE__
+      dir = File.expand_path "fixtures/tmp", __dir__
       path = "#{dir}/#{name}"
 
       FileUtils.mkdir_p dir
diff --git a/railties/test/code_statistics_test.rb b/railties/test/code_statistics_test.rb
index 4d80901217..7ad1ac3094 100644
--- a/railties/test/code_statistics_test.rb
+++ b/railties/test/code_statistics_test.rb
@@ -1,10 +1,12 @@
-require 'abstract_unit'
-require 'rails/code_statistics'
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "rails/code_statistics"
 
 class CodeStatisticsTest < ActiveSupport::TestCase
   def setup
-    @tmp_path = File.expand_path(File.join(File.dirname(__FILE__), 'fixtures', 'tmp'))
-    @dir_js   = File.join(@tmp_path, 'lib.js')
+    @tmp_path = File.expand_path("fixtures/tmp", __dir__)
+    @dir_js   = File.join(@tmp_path, "lib.js")
     FileUtils.mkdir_p(@dir_js)
   end
 
@@ -12,22 +14,21 @@ class CodeStatisticsTest < ActiveSupport::TestCase
     FileUtils.rm_rf(@tmp_path)
   end
 
-  test 'ignores directories that happen to have source files extensions' do
+  test "ignores directories that happen to have source files extensions" do
     assert_nothing_raised do
-      @code_statistics = CodeStatistics.new(['tmp dir', @tmp_path])
+      @code_statistics = CodeStatistics.new(["tmp dir", @tmp_path])
     end
   end
 
-  test 'ignores hidden files' do
-    File.write File.join(@tmp_path, '.example.rb'), <<-CODE
+  test "ignores hidden files" do
+    File.write File.join(@tmp_path, ".example.rb"), <<-CODE
       def foo
         puts 'foo'
       end
     CODE
 
     assert_nothing_raised do
-      CodeStatistics.new(['hidden file', @tmp_path])
+      CodeStatistics.new(["hidden file", @tmp_path])
     end
   end
-
 end
diff --git a/railties/test/command/base_test.rb b/railties/test/command/base_test.rb
new file mode 100644
index 0000000000..a49ae8aae7
--- /dev/null
+++ b/railties/test/command/base_test.rb
@@ -0,0 +1,13 @@
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "rails/command"
+require "rails/commands/generate/generate_command"
+require "rails/commands/secrets/secrets_command"
+
+class Rails::Command::BaseTest < ActiveSupport::TestCase
+  test "printing commands" do
+    assert_equal %w(generate), Rails::Command::GenerateCommand.printing_commands
+    assert_equal %w(secrets:setup secrets:edit secrets:show), Rails::Command::SecretsCommand.printing_commands
+  end
+end
diff --git a/railties/test/commands/console_test.rb b/railties/test/commands/console_test.rb
index de0cf0ba9e..45ab8d87ff 100644
--- a/railties/test/commands/console_test.rb
+++ b/railties/test/commands/console_test.rb
@@ -1,6 +1,9 @@
-require 'abstract_unit'
-require 'env_helpers'
-require 'rails/commands/console'
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "env_helpers"
+require "rails/command"
+require "rails/commands/console/console_command"
 
 class Rails::ConsoleTest < ActiveSupport::TestCase
   include EnvHelpers
@@ -40,14 +43,13 @@ class Rails::ConsoleTest < ActiveSupport::TestCase
   def test_start_with_sandbox
     start ["--sandbox"]
 
-
     assert app.console.started?
     assert app.sandbox
     assert_match(/Loading \w+ environment in sandbox \(Rails/, output)
   end
 
   def test_console_with_environment
-    start ["-e production"]
+    start ["-e", "production"]
     assert_match(/\sproduction\s/, output)
   end
 
@@ -64,52 +66,73 @@ class Rails::ConsoleTest < ActiveSupport::TestCase
   end
 
   def test_default_environment_with_rails_env
-    with_rails_env 'special-production' do
+    with_rails_env "special-production" do
       start
       assert_match(/\sspecial-production\s/, output)
     end
   end
 
   def test_default_environment_with_rack_env
-    with_rack_env 'production' do
+    with_rack_env "production" do
       start
       assert_match(/\sproduction\s/, output)
     end
   end
 
   def test_e_option
-    start ['-e', 'special-production']
+    start ["-e", "special-production"]
     assert_match(/\sspecial-production\s/, output)
   end
 
+  def test_e_option_is_properly_expanded
+    start ["-e", "prod"]
+    assert_match(/\sproduction\s/, output)
+  end
+
   def test_environment_option
-    start ['--environment=special-production']
+    start ["--environment=special-production"]
     assert_match(/\sspecial-production\s/, output)
   end
 
   def test_rails_env_is_production_when_first_argument_is_p
-    start ['p']
-    assert_match(/\sproduction\s/, output)
+    assert_deprecated do
+      start ["p"]
+      assert_match(/\sproduction\s/, output)
+    end
   end
 
   def test_rails_env_is_test_when_first_argument_is_t
-    start ['t']
-    assert_match(/\stest\s/, output)
+    assert_deprecated do
+      start ["t"]
+      assert_match(/\stest\s/, output)
+    end
   end
 
   def test_rails_env_is_development_when_argument_is_d
-    start ['d']
-    assert_match(/\sdevelopment\s/, output)
+    assert_deprecated do
+      start ["d"]
+      assert_match(/\sdevelopment\s/, output)
+    end
   end
 
   def test_rails_env_is_dev_when_argument_is_dev_and_dev_env_is_present
-    stubbed_console = Class.new(Rails::Console) do
-      def available_environments
-        ['dev']
+    Rails::Command::ConsoleCommand.class_eval do
+      alias_method :old_environments, :available_environments
+
+      define_method :available_environments do
+        ["dev"]
       end
     end
-    options = stubbed_console.parse_arguments(['dev'])
-    assert_match('dev', options[:environment])
+
+    assert_deprecated do
+      assert_match("dev", parse_arguments(["dev"])[:environment])
+    end
+  ensure
+    Rails::Command::ConsoleCommand.class_eval do
+      undef_method :available_environments
+      alias_method :available_environments, :old_environments
+      undef_method :old_environments
+    end
   end
 
   attr_reader :output
@@ -117,38 +140,40 @@ class Rails::ConsoleTest < ActiveSupport::TestCase
 
   private
 
-  def start(argv = [])
-    rails_console = Rails::Console.new(app, parse_arguments(argv))
-    @output = capture(:stdout) { rails_console.start }
-  end
+    def start(argv = [])
+      rails_console = Rails::Console.new(app, parse_arguments(argv))
+      @output = capture(:stdout) { rails_console.start }
+    end
 
-  def app
-    @app ||= build_app(FakeConsole)
-  end
+    def app
+      @app ||= build_app(FakeConsole)
+    end
 
-  def build_app(console)
-    mocked_console = Class.new do
-      attr_reader :sandbox, :console
+    def build_app(console)
+      mocked_console = Class.new do
+        attr_reader :sandbox, :console
 
-      def initialize(console)
-        @console = console
-      end
+        def initialize(console)
+          @console = console
+        end
 
-      def config
-        self
-      end
+        def config
+          self
+        end
 
-      def sandbox=(arg)
-        @sandbox = arg
-      end
+        def sandbox=(arg)
+          @sandbox = arg
+        end
 
-      def load_console
+        def load_console
+        end
       end
+      mocked_console.new(console)
     end
-    mocked_console.new(console)
-  end
 
-  def parse_arguments(args)
-    Rails::Console.parse_arguments(args)
-  end
+    def parse_arguments(args)
+      command = Rails::Command::ConsoleCommand.new([], args)
+      command.send(:extract_environment_option_from_argument)
+      command.options
+    end
 end
diff --git a/railties/test/commands/credentials_test.rb b/railties/test/commands/credentials_test.rb
new file mode 100644
index 0000000000..7c464b3fde
--- /dev/null
+++ b/railties/test/commands/credentials_test.rb
@@ -0,0 +1,74 @@
+# frozen_string_literal: true
+
+require "isolation/abstract_unit"
+require "env_helpers"
+require "rails/command"
+require "rails/commands/credentials/credentials_command"
+
+class Rails::Command::CredentialsCommandTest < ActiveSupport::TestCase
+  include ActiveSupport::Testing::Isolation, EnvHelpers
+
+  setup { build_app }
+
+  teardown { teardown_app }
+
+  test "edit without editor gives hint" do
+    run_edit_command(editor: "").tap do |output|
+      assert_match "No $EDITOR to open file in", output
+      assert_match "bin/rails credentials:edit", output
+    end
+  end
+
+  test "edit credentials" do
+    # Run twice to ensure credentials can be reread after first edit pass.
+    2.times do
+      assert_match(/access_key_id: 123/, run_edit_command)
+    end
+  end
+
+  test "edit command does not add master key to gitignore when already exist" do
+    run_edit_command
+
+    Dir.chdir(app_path) do
+      gitignore = File.read(".gitignore")
+      assert_equal 1, gitignore.scan(%r|config/master\.key|).length
+    end
+  end
+
+  test "edit command does not overwrite by default if credentials already exists" do
+    run_edit_command(editor: "eval echo api_key: abc >")
+    assert_match(/api_key: abc/, run_show_command)
+
+    run_edit_command
+    assert_match(/api_key: abc/, run_show_command)
+  end
+
+  test "show credentials" do
+    assert_match(/access_key_id: 123/, run_show_command)
+  end
+
+  test "show command raise error when require_master_key is specified and key does not exist" do
+    remove_file "config/master.key"
+    add_to_config "config.require_master_key = true"
+
+    assert_match(/Missing encryption key to decrypt file with/, run_show_command(allow_failure: true))
+  end
+
+  test "show command does not raise error when require_master_key is false and master key does not exist" do
+    remove_file "config/master.key"
+    add_to_config "config.require_master_key = false"
+
+    assert_match(/Missing master key to decrypt credentials/, run_show_command)
+  end
+
+  private
+    def run_edit_command(editor: "cat")
+      switch_env("EDITOR", editor) do
+        rails "credentials:edit"
+      end
+    end
+
+    def run_show_command(**options)
+      rails "credentials:show", **options
+    end
+end
diff --git a/railties/test/commands/dbconsole_test.rb b/railties/test/commands/dbconsole_test.rb
index a5aa6c14a2..6ad96b28c7 100644
--- a/railties/test/commands/dbconsole_test.rb
+++ b/railties/test/commands/dbconsole_test.rb
@@ -1,30 +1,31 @@
-require 'abstract_unit'
-require 'minitest/mock'
-require 'rails/commands/dbconsole'
-
-class Rails::DBConsoleTest < ActiveSupport::TestCase
+# frozen_string_literal: true
 
+require "abstract_unit"
+require "minitest/mock"
+require "rails/command"
+require "rails/commands/dbconsole/dbconsole_command"
 
+class Rails::DBConsoleTest < ActiveSupport::TestCase
   def setup
-    Rails::DBConsole.const_set('APP_PATH', 'rails/all')
+    Rails::DBConsole.const_set("APP_PATH", "rails/all")
   end
 
   def teardown
-    Rails::DBConsole.send(:remove_const, 'APP_PATH')
-    %w[PGUSER PGHOST PGPORT PGPASSWORD DATABASE_URL].each{|key| ENV.delete(key)}
+    Rails::DBConsole.send(:remove_const, "APP_PATH")
+    %w[PGUSER PGHOST PGPORT PGPASSWORD DATABASE_URL].each { |key| ENV.delete(key) }
   end
 
   def test_config_with_db_config_only
     config_sample = {
-      "test"=> {
-        "adapter"=> "sqlite3",
-        "host"=> "localhost",
-        "port"=> "9000",
-        "database"=> "foo_test",
-        "user"=> "foo",
-        "password"=> "bar",
-        "pool"=> "5",
-        "timeout"=> "3000"
+      "test" => {
+        "adapter" => "sqlite3",
+        "host" => "localhost",
+        "port" => "9000",
+        "database" => "foo_test",
+        "user" => "foo",
+        "password" => "bar",
+        "pool" => "5",
+        "timeout" => "3000"
       }
     }
     app_db_config(config_sample) do
@@ -41,7 +42,7 @@ class Rails::DBConsoleTest < ActiveSupport::TestCase
   end
 
   def test_config_with_database_url_only
-    ENV['DATABASE_URL'] = 'postgresql://foo:bar@localhost:9000/foo_test?pool=5&timeout=3000'
+    ENV["DATABASE_URL"] = "postgresql://foo:bar@localhost:9000/foo_test?pool=5&timeout=3000"
     expected = {
       "adapter"  => "postgresql",
       "host"     => "localhost",
@@ -60,7 +61,7 @@ class Rails::DBConsoleTest < ActiveSupport::TestCase
 
   def test_config_choose_database_url_if_exists
     host = "database-url-host.com"
-    ENV['DATABASE_URL'] = "postgresql://foo:bar@#{host}:9000/foo_test?pool=5&timeout=3000"
+    ENV["DATABASE_URL"] = "postgresql://foo:bar@#{host}:9000/foo_test?pool=5&timeout=3000"
     sample_config = {
       "test" => {
         "adapter"  => "postgresql",
@@ -81,144 +82,197 @@ class Rails::DBConsoleTest < ActiveSupport::TestCase
   def test_env
     assert_equal "test", Rails::DBConsole.new.environment
 
-    ENV['RAILS_ENV'] = nil
-    ENV['RACK_ENV'] = nil
+    ENV["RAILS_ENV"] = nil
+    ENV["RACK_ENV"] = nil
 
     Rails.stub(:respond_to?, false) do
       assert_equal "development", Rails::DBConsole.new.environment
 
-      ENV['RACK_ENV'] = "rack_env"
+      ENV["RACK_ENV"] = "rack_env"
       assert_equal "rack_env", Rails::DBConsole.new.environment
 
-      ENV['RAILS_ENV'] = "rails_env"
+      ENV["RAILS_ENV"] = "rails_env"
       assert_equal "rails_env", Rails::DBConsole.new.environment
     end
   ensure
-    ENV['RAILS_ENV'] = "test"
-    ENV['RACK_ENV'] = nil
+    ENV["RAILS_ENV"] = "test"
+    ENV["RACK_ENV"] = nil
   end
 
   def test_rails_env_is_development_when_argument_is_dev
-    Rails::DBConsole.stub(:available_environments, ['development', 'test']) do
-      options = Rails::DBConsole.send(:parse_arguments, ['dev'])
-      assert_match('development', options[:environment])
+    assert_deprecated do
+      stub_available_environments([ "development", "test" ]) do
+        assert_match("development", parse_arguments([ "dev" ])[:environment])
+      end
+    end
+  end
+
+  def test_rails_env_is_development_when_environment_option_is_dev
+    stub_available_environments([ "development", "test" ]) do
+      assert_match("development", parse_arguments([ "-e", "dev" ])[:environment])
     end
   end
 
   def test_rails_env_is_dev_when_argument_is_dev_and_dev_env_is_present
-    Rails::DBConsole.stub(:available_environments, ['dev']) do
-      options = Rails::DBConsole.send(:parse_arguments, ['dev'])
-      assert_match('dev', options[:environment])
+    assert_deprecated do
+      stub_available_environments([ "dev" ]) do
+        assert_match("dev", parse_arguments([ "dev" ])[:environment])
+      end
     end
   end
 
   def test_mysql
-    start(adapter: 'mysql2', database: 'db')
+    start(adapter: "mysql2", database: "db")
     assert !aborted
-    assert_equal [%w[mysql mysql5], 'db'], dbconsole.find_cmd_and_exec_args
+    assert_equal [%w[mysql mysql5], "db"], dbconsole.find_cmd_and_exec_args
   end
 
   def test_mysql_full
-    start(adapter: 'mysql2', database: 'db', host: 'locahost', port: 1234, socket: 'socket', username: 'user', password: 'qwerty', encoding: 'UTF-8')
+    start(adapter: "mysql2", database: "db", host: "locahost", port: 1234, socket: "socket", username: "user", password: "qwerty", encoding: "UTF-8")
     assert !aborted
-    assert_equal [%w[mysql mysql5], '--host=locahost', '--port=1234', '--socket=socket', '--user=user', '--default-character-set=UTF-8', '-p', 'db'], dbconsole.find_cmd_and_exec_args
+    assert_equal [%w[mysql mysql5], "--host=locahost", "--port=1234", "--socket=socket", "--user=user", "--default-character-set=UTF-8", "-p", "db"], dbconsole.find_cmd_and_exec_args
   end
 
   def test_mysql_include_password
-    start({adapter: 'mysql2', database: 'db', username: 'user', password: 'qwerty'}, ['-p'])
+    start({ adapter: "mysql2", database: "db", username: "user", password: "qwerty" }, ["-p"])
     assert !aborted
-    assert_equal [%w[mysql mysql5], '--user=user', '--password=qwerty', 'db'], dbconsole.find_cmd_and_exec_args
+    assert_equal [%w[mysql mysql5], "--user=user", "--password=qwerty", "db"], dbconsole.find_cmd_and_exec_args
   end
 
   def test_postgresql
-    start(adapter: 'postgresql', database: 'db')
+    start(adapter: "postgresql", database: "db")
     assert !aborted
-    assert_equal ['psql', 'db'], dbconsole.find_cmd_and_exec_args
+    assert_equal ["psql", "db"], dbconsole.find_cmd_and_exec_args
   end
 
   def test_postgresql_full
-    start(adapter: 'postgresql', database: 'db', username: 'user', password: 'q1w2e3', host: 'host', port: 5432)
+    start(adapter: "postgresql", database: "db", username: "user", password: "q1w2e3", host: "host", port: 5432)
     assert !aborted
-    assert_equal ['psql', 'db'], dbconsole.find_cmd_and_exec_args
-    assert_equal 'user', ENV['PGUSER']
-    assert_equal 'host', ENV['PGHOST']
-    assert_equal '5432', ENV['PGPORT']
-    assert_not_equal 'q1w2e3', ENV['PGPASSWORD']
+    assert_equal ["psql", "db"], dbconsole.find_cmd_and_exec_args
+    assert_equal "user", ENV["PGUSER"]
+    assert_equal "host", ENV["PGHOST"]
+    assert_equal "5432", ENV["PGPORT"]
+    assert_not_equal "q1w2e3", ENV["PGPASSWORD"]
   end
 
   def test_postgresql_include_password
-    start({adapter: 'postgresql', database: 'db', username: 'user', password: 'q1w2e3'}, ['-p'])
+    start({ adapter: "postgresql", database: "db", username: "user", password: "q1w2e3" }, ["-p"])
     assert !aborted
-    assert_equal ['psql', 'db'], dbconsole.find_cmd_and_exec_args
-    assert_equal 'user', ENV['PGUSER']
-    assert_equal 'q1w2e3', ENV['PGPASSWORD']
+    assert_equal ["psql", "db"], dbconsole.find_cmd_and_exec_args
+    assert_equal "user", ENV["PGUSER"]
+    assert_equal "q1w2e3", ENV["PGPASSWORD"]
   end
 
   def test_sqlite3
-    start(adapter: 'sqlite3', database: 'db.sqlite3')
+    start(adapter: "sqlite3", database: "db.sqlite3")
     assert !aborted
-    assert_equal ['sqlite3', Rails.root.join('db.sqlite3').to_s], dbconsole.find_cmd_and_exec_args
+    assert_equal ["sqlite3", Rails.root.join("db.sqlite3").to_s], dbconsole.find_cmd_and_exec_args
   end
 
   def test_sqlite3_mode
-    start({adapter: 'sqlite3', database: 'db.sqlite3'}, ['--mode', 'html'])
+    start({ adapter: "sqlite3", database: "db.sqlite3" }, ["--mode", "html"])
     assert !aborted
-    assert_equal ['sqlite3', '-html', Rails.root.join('db.sqlite3').to_s], dbconsole.find_cmd_and_exec_args
+    assert_equal ["sqlite3", "-html", Rails.root.join("db.sqlite3").to_s], dbconsole.find_cmd_and_exec_args
   end
 
   def test_sqlite3_header
-    start({adapter: 'sqlite3', database: 'db.sqlite3'}, ['--header'])
-    assert_equal ['sqlite3', '-header', Rails.root.join('db.sqlite3').to_s], dbconsole.find_cmd_and_exec_args
+    start({ adapter: "sqlite3", database: "db.sqlite3" }, ["--header"])
+    assert_equal ["sqlite3", "-header", Rails.root.join("db.sqlite3").to_s], dbconsole.find_cmd_and_exec_args
   end
 
   def test_sqlite3_db_absolute_path
-    start(adapter: 'sqlite3', database: '/tmp/db.sqlite3')
+    start(adapter: "sqlite3", database: "/tmp/db.sqlite3")
     assert !aborted
-    assert_equal ['sqlite3', '/tmp/db.sqlite3'], dbconsole.find_cmd_and_exec_args
+    assert_equal ["sqlite3", "/tmp/db.sqlite3"], dbconsole.find_cmd_and_exec_args
   end
 
   def test_sqlite3_db_without_defined_rails_root
     Rails.stub(:respond_to?, false) do
-      start(adapter: 'sqlite3', database: 'config/db.sqlite3')
+      start(adapter: "sqlite3", database: "config/db.sqlite3")
       assert !aborted
-      assert_equal ['sqlite3', Rails.root.join('../config/db.sqlite3').to_s], dbconsole.find_cmd_and_exec_args
+      assert_equal ["sqlite3", Rails.root.join("../config/db.sqlite3").to_s], dbconsole.find_cmd_and_exec_args
     end
   end
 
   def test_oracle
-    start(adapter: 'oracle', database: 'db', username: 'user', password: 'secret')
+    start(adapter: "oracle", database: "db", username: "user", password: "secret")
     assert !aborted
-    assert_equal ['sqlplus', 'user@db'], dbconsole.find_cmd_and_exec_args
+    assert_equal ["sqlplus", "user@db"], dbconsole.find_cmd_and_exec_args
   end
 
   def test_oracle_include_password
-    start({adapter: 'oracle', database: 'db', username: 'user', password: 'secret'}, ['-p'])
+    start({ adapter: "oracle", database: "db", username: "user", password: "secret" }, ["-p"])
     assert !aborted
-    assert_equal ['sqlplus', 'user/secret@db'], dbconsole.find_cmd_and_exec_args
+    assert_equal ["sqlplus", "user/secret@db"], dbconsole.find_cmd_and_exec_args
+  end
+
+  def test_sqlserver
+    start(adapter: "sqlserver", database: "db", username: "user", password: "secret", host: "localhost", port: 1433)
+    assert_not aborted
+    assert_equal ["sqsh", "-D", "db", "-U", "user", "-P", "secret", "-S", "localhost:1433"], dbconsole.find_cmd_and_exec_args
   end
 
   def test_unknown_command_line_client
-    start(adapter: 'unknown', database: 'db')
+    start(adapter: "unknown", database: "db")
     assert aborted
     assert_match(/Unknown command-line client for db/, output)
   end
 
+  def test_primary_is_automatically_picked_with_3_level_configuration
+    sample_config = {
+      "test" => {
+        "primary" => {
+          "adapter" => "postgresql"
+        }
+      }
+    }
+
+    app_db_config(sample_config) do
+      assert_equal "postgresql", Rails::DBConsole.new.config["adapter"]
+    end
+  end
+
+  def test_specifying_a_custom_connection_and_environment
+    stub_available_environments(["development"]) do
+      dbconsole = parse_arguments(["-c", "custom", "-e", "development"])
+
+      assert_equal "development", dbconsole[:environment]
+      assert_equal "custom", dbconsole.connection
+    end
+  end
+
+  def test_specifying_a_missing_connection
+    app_db_config({}) do
+      e = assert_raises(ActiveRecord::AdapterNotSpecified) do
+        Rails::Command.invoke(:dbconsole, ["-c", "i_do_not_exist"])
+      end
+
+      assert_includes e.message, "'i_do_not_exist' connection is not configured."
+    end
+  end
+
+  def test_specifying_a_missing_environment
+    app_db_config({}) do
+      e = assert_raises(ActiveRecord::AdapterNotSpecified) do
+        Rails::Command.invoke(:dbconsole)
+      end
+
+      assert_includes e.message, "'test' database is not configured."
+    end
+  end
+
   def test_print_help_short
     stdout = capture(:stdout) do
-      start({}, ['-h'])
+      Rails::Command.invoke(:dbconsole, ["-h"])
     end
-    assert aborted
-    assert_equal '', output
-    assert_match(/Usage:.*dbconsole/, stdout)
+    assert_match(/bin\/rails dbconsole \[environment\]/, stdout)
   end
 
   def test_print_help_long
     stdout = capture(:stdout) do
-      start({}, ['--help'])
+      Rails::Command.invoke(:dbconsole, ["--help"])
     end
-    assert aborted
-    assert_equal '', output
-    assert_match(/Usage:.*dbconsole/, stdout)
+    assert_match(/bin\/rails dbconsole \[environment\]/, stdout)
   end
 
   attr_reader :aborted, :output
@@ -226,39 +280,76 @@ class Rails::DBConsoleTest < ActiveSupport::TestCase
 
   private
 
-  def app_db_config(results)
-    Rails.application.config.stub(:database_configuration, results || {}) do
-      yield
+    def app_db_config(results)
+      Rails.application.config.stub(:database_configuration, results || {}) do
+        yield
+      end
     end
-  end
 
-  def dbconsole
-    @dbconsole ||= Class.new(Rails::DBConsole) do
-      attr_reader :find_cmd_and_exec_args
+    def make_dbconsole
+      Class.new(Rails::DBConsole) do
+        attr_reader :find_cmd_and_exec_args
 
-      def find_cmd_and_exec(*args)
-        @find_cmd_and_exec_args = args
+        def find_cmd_and_exec(*args)
+          @find_cmd_and_exec_args = args
+        end
       end
-    end.new(nil)
-  end
+    end
+
+    attr_reader :dbconsole
 
-  def start(config = {}, argv = [])
-    dbconsole.stub(:config, config.stringify_keys) do
-      dbconsole.stub(:arguments, argv) do
-        capture_abort { dbconsole.start }
+    def start(config = {}, argv = [])
+      @dbconsole = make_dbconsole.new(parse_arguments(argv))
+      @dbconsole.stub(:config, config.stringify_keys) do
+        capture_abort { @dbconsole.start }
       end
     end
-  end
 
-  def capture_abort
-    @aborted = false
-    @output = capture(:stderr) do
-      begin
-        yield
-      rescue SystemExit
-        @aborted = true
+    def capture_abort
+      @aborted = false
+      @output = capture(:stderr) do
+        begin
+          yield
+        rescue SystemExit
+          @aborted = true
+        end
       end
     end
-  end
 
+    def stub_available_environments(environments)
+      Rails::Command::DbconsoleCommand.class_eval do
+        alias_method :old_environments, :available_environments
+
+        define_method :available_environments do
+          environments
+        end
+      end
+
+      yield
+    ensure
+      Rails::Command::DbconsoleCommand.class_eval do
+        undef_method :available_environments
+        alias_method :available_environments, :old_environments
+        undef_method :old_environments
+      end
+    end
+
+    def parse_arguments(args)
+      Rails::Command::DbconsoleCommand.class_eval do
+        alias_method :old_perform, :perform
+        define_method(:perform) do
+          extract_environment_option_from_argument
+
+          options
+        end
+      end
+
+      Rails::Command.invoke(:dbconsole, args)
+    ensure
+      Rails::Command::DbconsoleCommand.class_eval do
+        undef_method :perform
+        alias_method :perform, :old_perform
+        undef_method :old_perform
+      end
+    end
 end
diff --git a/railties/test/commands/encrypted_test.rb b/railties/test/commands/encrypted_test.rb
new file mode 100644
index 0000000000..6647dcc902
--- /dev/null
+++ b/railties/test/commands/encrypted_test.rb
@@ -0,0 +1,94 @@
+# frozen_string_literal: true
+
+require "isolation/abstract_unit"
+require "env_helpers"
+require "rails/command"
+require "rails/commands/encrypted/encrypted_command"
+
+class Rails::Command::EncryptedCommandTest < ActiveSupport::TestCase
+  include ActiveSupport::Testing::Isolation, EnvHelpers
+
+  setup :build_app
+  teardown :teardown_app
+
+  test "edit without editor gives hint" do
+    run_edit_command("config/tokens.yml.enc", editor: "").tap do |output|
+      assert_match "No $EDITOR to open file in", output
+      assert_match "bin/rails encrypted:edit", output
+    end
+  end
+
+  test "edit encrypted file" do
+    # Run twice to ensure file can be reread after first edit pass.
+    2.times do
+      assert_match(/access_key_id: 123/, run_edit_command("config/tokens.yml.enc"))
+    end
+  end
+
+  test "edit command does not add master key to gitignore when already exist" do
+    run_edit_command("config/tokens.yml.enc")
+
+    Dir.chdir(app_path) do
+      assert_match "/config/master.key", File.read(".gitignore")
+    end
+  end
+
+  test "edit encrypts file with custom key" do
+    run_edit_command("config/tokens.yml.enc", key: "config/tokens.key")
+
+    Dir.chdir(app_path) do
+      assert File.exist?("config/tokens.yml.enc")
+      assert File.exist?("config/tokens.key")
+
+      assert_match "/config/tokens.key", File.read(".gitignore")
+    end
+
+    assert_match(/access_key_id: 123/, run_edit_command("config/tokens.yml.enc", key: "config/tokens.key"))
+  end
+
+  test "show encrypted file with custom key" do
+    run_edit_command("config/tokens.yml.enc", key: "config/tokens.key")
+
+    assert_match(/access_key_id: 123/, run_show_command("config/tokens.yml.enc", key: "config/tokens.key"))
+  end
+
+  test "show command raise error when require_master_key is specified and key does not exist" do
+    add_to_config "config.require_master_key = true"
+
+    assert_match(/Missing encryption key to decrypt file with/,
+      run_show_command("config/tokens.yml.enc", key: "unexist.key", allow_failure: true))
+  end
+
+  test "show command does not raise error when require_master_key is false and master key does not exist" do
+    remove_file "config/master.key"
+    add_to_config "config.require_master_key = false"
+
+    assert_match(/Missing 'config\/master\.key' to decrypt data/, run_show_command("config/tokens.yml.enc"))
+  end
+
+  test "won't corrupt encrypted file when passed wrong key" do
+    run_edit_command("config/tokens.yml.enc", key: "config/tokens.key")
+
+    assert_match "passed the wrong key",
+      run_edit_command("config/tokens.yml.enc", allow_failure: true)
+
+    assert_match(/access_key_id: 123/, run_show_command("config/tokens.yml.enc", key: "config/tokens.key"))
+  end
+
+  private
+    def run_edit_command(file, key: nil, editor: "cat", **options)
+      switch_env("EDITOR", editor) do
+        rails "encrypted:edit", prepare_args(file, key), **options
+      end
+    end
+
+    def run_show_command(file, key: nil, **options)
+      rails "encrypted:show", prepare_args(file, key), **options
+    end
+
+    def prepare_args(file, key)
+      args = [ file ]
+      args.push("--key", key) if key
+      args
+    end
+end
diff --git a/railties/test/commands/secrets_test.rb b/railties/test/commands/secrets_test.rb
new file mode 100644
index 0000000000..6b9f284a0c
--- /dev/null
+++ b/railties/test/commands/secrets_test.rb
@@ -0,0 +1,77 @@
+# frozen_string_literal: true
+
+require "isolation/abstract_unit"
+require "env_helpers"
+require "rails/command"
+require "rails/commands/secrets/secrets_command"
+
+class Rails::Command::SecretsCommandTest < ActiveSupport::TestCase
+  include ActiveSupport::Testing::Isolation, EnvHelpers
+
+  setup :build_app
+  teardown :teardown_app
+
+  test "edit without editor gives hint" do
+    assert_match "No $EDITOR to open decrypted secrets in", run_edit_command(editor: "")
+  end
+
+  test "encrypted secrets are deprecated when using credentials" do
+    assert_match "Encrypted secrets is deprecated", run_setup_command
+    assert_equal 1, $?.exitstatus
+    assert_not File.exist?("config/secrets.yml.enc")
+  end
+
+  test "encrypted secrets are deprecated when running edit without setup" do
+    assert_match "Encrypted secrets is deprecated", run_setup_command
+    assert_equal 1, $?.exitstatus
+    assert_not File.exist?("config/secrets.yml.enc")
+  end
+
+  test "encrypted secrets are deprecated for 5.1 config/secrets.yml apps" do
+    Dir.chdir(app_path) do
+      FileUtils.rm("config/credentials.yml.enc")
+      FileUtils.touch("config/secrets.yml")
+
+      assert_match "Encrypted secrets is deprecated", run_setup_command
+      assert_equal 1, $?.exitstatus
+      assert_not File.exist?("config/secrets.yml.enc")
+    end
+  end
+
+  test "edit secrets" do
+    prevent_deprecation
+
+    # Run twice to ensure encrypted secrets can be reread after first edit pass.
+    2.times do
+      assert_match(/external_api_key: 1466aac22e6a869134be3d09b9e89232fc2c2289/, run_edit_command)
+    end
+  end
+
+  test "show secrets" do
+    prevent_deprecation
+
+    assert_match(/external_api_key: 1466aac22e6a869134be3d09b9e89232fc2c2289/, run_show_command)
+  end
+
+  private
+    def prevent_deprecation
+      Dir.chdir(app_path) do
+        File.write("config/secrets.yml.key", "f731758c639da2604dfb6bf3d1025de8")
+        File.write("config/secrets.yml.enc", "sEB0mHxDbeP1/KdnMk00wyzPFACl9K6t0cZWn5/Mfx/YbTHvnI07vrneqHg9kaH3wOS7L6pIQteu1P077OtE4BSx/ZRc/sgQPHyWu/tXsrfHqnPNpayOF/XZqizE91JacSFItNMWpuPsp9ynbzz+7cGhoB1S4aPNIU6u0doMrzdngDbijsaAFJmsHIQh6t/QHoJx--8aMoE0PvUWmw1Iqz--ldFqnM/K0g9k17M8PKoN/Q==")
+      end
+    end
+
+    def run_edit_command(editor: "cat")
+      switch_env("EDITOR", editor) do
+        rails "secrets:edit", allow_failure: true
+      end
+    end
+
+    def run_show_command
+      rails "secrets:show", allow_failure: true
+    end
+
+    def run_setup_command
+      rails "secrets:setup", allow_failure: true
+    end
+end
diff --git a/railties/test/commands/server_test.rb b/railties/test/commands/server_test.rb
index 38a1605d1f..33715ea75f 100644
--- a/railties/test/commands/server_test.rb
+++ b/railties/test/commands/server_test.rb
@@ -1,115 +1,204 @@
-require 'abstract_unit'
-require 'env_helpers'
-require 'rails/commands/server'
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "env_helpers"
+require "rails/command"
+require "rails/commands/server/server_command"
 
 class Rails::ServerTest < ActiveSupport::TestCase
   include EnvHelpers
 
   def test_environment_with_server_option
-    args    = ["thin", "-e", "production"]
-    options = Rails::Server::Options.new.parse!(args)
-    assert_equal 'production', options[:environment]
-    assert_equal 'thin', options[:server]
+    args = ["thin", "-e", "production"]
+    options = parse_arguments(args)
+    assert_equal "production", options[:environment]
+    assert_equal "thin", options[:server]
   end
 
   def test_environment_without_server_option
-    args    = ["-e", "production"]
-    options = Rails::Server::Options.new.parse!(args)
-    assert_equal 'production', options[:environment]
+    args = ["-e", "production"]
+    options = parse_arguments(args)
+    assert_equal "production", options[:environment]
     assert_nil options[:server]
   end
 
+  def test_daemon_with_option
+    args = ["-d"]
+    options = parse_arguments(args)
+    assert_equal true, options[:daemonize]
+  end
+
+  def test_daemon_without_option
+    args = []
+    options = parse_arguments(args)
+    assert_equal false, options[:daemonize]
+  end
+
   def test_server_option_without_environment
-    args    = ["thin"]
-    options = Rails::Server::Options.new.parse!(args)
-    assert_nil options[:environment]
-    assert_equal 'thin', options[:server]
+    args = ["thin"]
+    with_rack_env nil do
+      with_rails_env nil do
+        options = parse_arguments(args)
+        assert_equal "development",  options[:environment]
+        assert_equal "thin", options[:server]
+      end
+    end
   end
 
   def test_environment_with_rails_env
     with_rack_env nil do
-      with_rails_env 'production' do
-        server = Rails::Server.new
-        assert_equal 'production', server.options[:environment]
+      with_rails_env "production" do
+        options = parse_arguments
+        assert_equal "production", options[:environment]
       end
     end
   end
 
   def test_environment_with_rack_env
     with_rails_env nil do
-      with_rack_env 'production' do
-        server = Rails::Server.new
-        assert_equal 'production', server.options[:environment]
+      with_rack_env "production" do
+        options = parse_arguments
+        assert_equal "production", options[:environment]
       end
     end
   end
 
   def test_environment_with_port
     switch_env "PORT", "1234" do
-      server = Rails::Server.new
-      assert_equal 1234, server.options[:Port]
+      options = parse_arguments
+      assert_equal 1234, options[:Port]
+    end
+  end
+
+  def test_environment_with_host
+    switch_env "HOST", "1.2.3.4" do
+      options = parse_arguments
+      assert_equal "1.2.3.4", options[:Host]
     end
   end
 
   def test_caching_without_option
     args = []
-    options = Rails::Server::Options.new.parse!(args)
-    merged_options = Rails::Server.new.default_options.merge(options)
-    assert_equal nil, merged_options[:caching]
+    options = parse_arguments(args)
+    assert_nil options[:caching]
   end
 
   def test_caching_with_option
     args = ["--dev-caching"]
-    options = Rails::Server::Options.new.parse!(args)
+    options = parse_arguments(args)
     assert_equal true, options[:caching]
 
     args = ["--no-dev-caching"]
-    options = Rails::Server::Options.new.parse!(args)
+    options = parse_arguments(args)
     assert_equal false, options[:caching]
   end
 
+  def test_early_hints_with_option
+    args = ["--early-hints"]
+    options = parse_arguments(args)
+    assert_equal true, options[:early_hints]
+  end
+
+  def test_early_hints_is_nil_by_default
+    args = []
+    options = parse_arguments(args)
+    assert_nil options[:early_hints]
+  end
+
   def test_log_stdout
     with_rack_env nil do
       with_rails_env nil do
         args    = []
-        options = Rails::Server::Options.new.parse!(args)
+        options = parse_arguments(args)
         assert_equal true, options[:log_stdout]
 
         args    = ["-e", "development"]
-        options = Rails::Server::Options.new.parse!(args)
+        options = parse_arguments(args)
         assert_equal true, options[:log_stdout]
 
         args    = ["-e", "production"]
-        options = Rails::Server::Options.new.parse!(args)
+        options = parse_arguments(args)
         assert_equal false, options[:log_stdout]
 
-        with_rack_env 'development' do
+        with_rack_env "development" do
           args    = []
-          options = Rails::Server::Options.new.parse!(args)
+          options = parse_arguments(args)
           assert_equal true, options[:log_stdout]
         end
 
-        with_rack_env 'production' do
+        with_rack_env "production" do
           args    = []
-          options = Rails::Server::Options.new.parse!(args)
+          options = parse_arguments(args)
           assert_equal false, options[:log_stdout]
         end
 
-        with_rails_env 'development' do
+        with_rails_env "development" do
           args    = []
-          options = Rails::Server::Options.new.parse!(args)
+          options = parse_arguments(args)
           assert_equal true, options[:log_stdout]
         end
 
-        with_rails_env 'production' do
+        with_rails_env "production" do
           args    = []
-          options = Rails::Server::Options.new.parse!(args)
+          options = parse_arguments(args)
           assert_equal false, options[:log_stdout]
         end
       end
     end
   end
 
+  def test_host
+    with_rails_env "development" do
+      options = parse_arguments([])
+      assert_equal "localhost", options[:Host]
+    end
+
+    with_rails_env "production" do
+      options = parse_arguments([])
+      assert_equal "0.0.0.0", options[:Host]
+    end
+
+    with_rails_env "development" do
+      args = ["-b", "127.0.0.1"]
+      options = parse_arguments(args)
+      assert_equal "127.0.0.1", options[:Host]
+    end
+  end
+
+  def test_argument_precedence_over_environment_variable
+    switch_env "PORT", "1234" do
+      args = ["-p", "5678"]
+      options = parse_arguments(args)
+      assert_equal 5678, options[:Port]
+    end
+
+    switch_env "PORT", "1234" do
+      args = ["-p", "3000"]
+      options = parse_arguments(args)
+      assert_equal 3000, options[:Port]
+    end
+
+    switch_env "HOST", "1.2.3.4" do
+      args = ["-b", "127.0.0.1"]
+      options = parse_arguments(args)
+      assert_equal "127.0.0.1", options[:Host]
+    end
+  end
+
+  def test_records_user_supplied_options
+    server_options = parse_arguments(["-p", 3001])
+    assert_equal [:Port], server_options[:user_supplied_options]
+
+    server_options = parse_arguments(["--port", 3001])
+    assert_equal [:Port], server_options[:user_supplied_options]
+
+    server_options = parse_arguments(["-p3001", "-C", "--binding", "127.0.0.1"])
+    assert_equal [:Port, :Host, :caching], server_options[:user_supplied_options]
+
+    server_options = parse_arguments(["--port=3001"])
+    assert_equal [:Port], server_options[:user_supplied_options]
+  end
+
   def test_default_options
     server = Rails::Server.new
     old_default_options = server.default_options
@@ -121,15 +210,19 @@ class Rails::ServerTest < ActiveSupport::TestCase
 
   def test_restart_command_contains_customized_options
     original_args = ARGV.dup
-    args = ["-p", "4567"]
+    args = %w(-p 4567 -b 127.0.0.1 -c dummy_config.ru -d -e test -P tmp/server.pid -C)
     ARGV.replace args
 
-    options = Rails::Server::Options.new.parse! args
-    server = Rails::Server.new options
-    expected = "bin/rails server -p 4567"
+    options = parse_arguments(args)
+    expected = "bin/rails server  -p 4567 -b 127.0.0.1 -c dummy_config.ru -d -e test -P tmp/server.pid -C --restart"
 
-    assert_equal expected, server.default_options[:restart_cmd]
+    assert_equal expected, options[:restart_cmd]
   ensure
     ARGV.replace original_args
   end
+
+  private
+    def parse_arguments(args = [])
+      Rails::Command::ServerCommand.new([], args).server_options
+    end
 end
diff --git a/railties/test/configuration/middleware_stack_proxy_test.rb b/railties/test/configuration/middleware_stack_proxy_test.rb
index d5072614cf..bc72b7f0c9 100644
--- a/railties/test/configuration/middleware_stack_proxy_test.rb
+++ b/railties/test/configuration/middleware_stack_proxy_test.rb
@@ -1,8 +1,10 @@
-require 'active_support'
-require 'active_support/testing/autorun'
-require 'rails/configuration'
-require 'active_support/test_case'
-require 'minitest/mock'
+# frozen_string_literal: true
+
+require "active_support"
+require "active_support/testing/autorun"
+require "rails/configuration"
+require "active_support/test_case"
+require "minitest/mock"
 
 module Rails
   module Configuration
@@ -50,12 +52,12 @@ module Rails
 
       private
 
-      def assert_playback(msg_name, args)
-        mock = Minitest::Mock.new
-        mock.expect :send, nil, [msg_name, args]
-        @stack.merge_into(mock)
-        mock.verify
-      end
+        def assert_playback(msg_name, args)
+          mock = Minitest::Mock.new
+          mock.expect :send, nil, [msg_name, args]
+          @stack.merge_into(mock)
+          mock.verify
+        end
     end
   end
 end
diff --git a/railties/test/console_helpers.rb b/railties/test/console_helpers.rb
new file mode 100644
index 0000000000..8350fce5ee
--- /dev/null
+++ b/railties/test/console_helpers.rb
@@ -0,0 +1,25 @@
+# frozen_string_literal: true
+
+begin
+  require "pty"
+rescue LoadError
+end
+
+module ConsoleHelpers
+  def assert_output(expected, io, timeout = 10)
+    timeout = Time.now + timeout
+
+    output = "".dup
+    until output.include?(expected) || Time.now > timeout
+      if IO.select([io], [], [], 0.1)
+        output << io.read(1)
+      end
+    end
+
+    assert_includes output, expected, "#{expected.inspect} expected, but got:\n\n#{output}"
+  end
+
+  def available_pty?
+    defined?(PTY) && PTY.respond_to?(:open)
+  end
+end
diff --git a/railties/test/engine/commands_test.rb b/railties/test/engine/commands_test.rb
new file mode 100644
index 0000000000..aeb64d445b
--- /dev/null
+++ b/railties/test/engine/commands_test.rb
@@ -0,0 +1,80 @@
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "console_helpers"
+
+class Rails::Engine::CommandsTest < ActiveSupport::TestCase
+  include ConsoleHelpers
+
+  def setup
+    @destination_root = Dir.mktmpdir("bukkits")
+    Dir.chdir(@destination_root) { `bundle exec rails plugin new bukkits --mountable` }
+  end
+
+  def teardown
+    FileUtils.rm_rf(@destination_root)
+  end
+
+  def test_help_command_work_inside_engine
+    output = capture(:stderr) do
+      Dir.chdir(plugin_path) { `bin/rails --help` }
+    end
+    assert_no_match "NameError", output
+  end
+
+  def test_runner_command_work_inside_engine
+    output = capture(:stdout) do
+      Dir.chdir(plugin_path) { system("bin/rails runner 'puts Rails.env'") }
+    end
+
+    assert_equal "test", output.strip
+  end
+
+  def test_console_command_work_inside_engine
+    skip "PTY unavailable" unless available_pty?
+
+    master, slave = PTY.open
+    spawn_command("console", slave)
+    assert_output(">", master)
+  ensure
+    master.puts "quit"
+  end
+
+  def test_dbconsole_command_work_inside_engine
+    skip "PTY unavailable" unless available_pty?
+
+    master, slave = PTY.open
+    spawn_command("dbconsole", slave)
+    assert_output("sqlite>", master)
+  ensure
+    master.puts ".exit"
+  end
+
+  def test_server_command_work_inside_engine
+    skip "PTY unavailable" unless available_pty?
+
+    master, slave = PTY.open
+    pid = spawn_command("server", slave)
+    assert_output("Listening on", master)
+  ensure
+    kill(pid)
+  end
+
+  private
+    def plugin_path
+      "#{@destination_root}/bukkits"
+    end
+
+    def spawn_command(command, fd)
+      Process.spawn(
+        "#{plugin_path}/bin/rails #{command}",
+        in: fd, out: fd, err: fd
+      )
+    end
+
+    def kill(pid)
+      Process.kill("TERM", pid)
+      Process.wait(pid)
+    rescue Errno::ESRCH
+    end
+end
diff --git a/railties/test/engine/test_test.rb b/railties/test/engine/test_test.rb
new file mode 100644
index 0000000000..18af85a0aa
--- /dev/null
+++ b/railties/test/engine/test_test.rb
@@ -0,0 +1,31 @@
+# frozen_string_literal: true
+
+require "abstract_unit"
+
+class Rails::Engine::TestTest < ActiveSupport::TestCase
+  setup do
+    @destination_root = Dir.mktmpdir("bukkits")
+    Dir.chdir(@destination_root) { `bundle exec rails plugin new bukkits --mountable` }
+  end
+
+  teardown do
+    FileUtils.rm_rf(@destination_root)
+  end
+
+  test "automatically synchronize test schema" do
+    Dir.chdir(plugin_path) do
+      # In order to confirm that migration files are loaded, generate multiple migration files.
+      `bin/rails generate model user name:string;
+       bin/rails generate model todo name:string;
+       RAILS_ENV=development bin/rails db:migrate`
+
+      output = `bin/rails test test/models/bukkits/user_test.rb`
+      assert_includes(output, "0 runs, 0 assertions, 0 failures, 0 errors, 0 skips")
+    end
+  end
+
+  private
+    def plugin_path
+      "#{@destination_root}/bukkits"
+    end
+end
diff --git a/railties/test/engine_test.rb b/railties/test/engine_test.rb
index f46fb748f5..4bd8a07085 100644
--- a/railties/test/engine_test.rb
+++ b/railties/test/engine_test.rb
@@ -1,4 +1,6 @@
-require 'abstract_unit'
+# frozen_string_literal: true
+
+require "abstract_unit"
 
 class EngineTest < ActiveSupport::TestCase
   test "reports routes as available only if they're actually present" do
diff --git a/railties/test/env_helpers.rb b/railties/test/env_helpers.rb
index 330fe150ca..336832b867 100644
--- a/railties/test/env_helpers.rb
+++ b/railties/test/env_helpers.rb
@@ -1,30 +1,32 @@
-require 'rails'
+# frozen_string_literal: true
+
+require "rails"
 
 module EnvHelpers
   private
 
-  def with_rails_env(env)
-    Rails.instance_variable_set :@_env, nil
-    switch_env 'RAILS_ENV', env do
-      switch_env 'RACK_ENV', nil do
-        yield
+    def with_rails_env(env)
+      Rails.instance_variable_set :@_env, nil
+      switch_env "RAILS_ENV", env do
+        switch_env "RACK_ENV", nil do
+          yield
+        end
       end
     end
-  end
 
-  def with_rack_env(env)
-    Rails.instance_variable_set :@_env, nil
-    switch_env 'RACK_ENV', env do
-      switch_env 'RAILS_ENV', nil do
-        yield
+    def with_rack_env(env)
+      Rails.instance_variable_set :@_env, nil
+      switch_env "RACK_ENV", env do
+        switch_env "RAILS_ENV", nil do
+          yield
+        end
       end
     end
-  end
 
-  def switch_env(key, value)
-    old, ENV[key] = ENV[key], value
-    yield
-  ensure
-    ENV[key] = old
-  end
+    def switch_env(key, value)
+      old, ENV[key] = ENV[key], value
+      yield
+    ensure
+      ENV[key] = old
+    end
 end
diff --git a/railties/test/fixtures/about_yml_plugins/bad_about_yml/about.yml b/railties/test/fixtures/about_yml_plugins/bad_about_yml/about.yml
deleted file mode 100644
index fe80872a16..0000000000
--- a/railties/test/fixtures/about_yml_plugins/bad_about_yml/about.yml
+++ /dev/null
@@ -1 +0,0 @@
-# an empty YAML file - any content in here seems to get parsed as a string
\ No newline at end of file
diff --git a/railties/test/fixtures/about_yml_plugins/bad_about_yml/init.rb b/railties/test/fixtures/about_yml_plugins/bad_about_yml/init.rb
deleted file mode 100644
index d4262f8971..0000000000
--- a/railties/test/fixtures/about_yml_plugins/bad_about_yml/init.rb
+++ /dev/null
@@ -1 +0,0 @@
-# intentionally empty
\ No newline at end of file
diff --git a/railties/test/fixtures/about_yml_plugins/plugin_without_about_yml/init.rb b/railties/test/fixtures/about_yml_plugins/plugin_without_about_yml/init.rb
deleted file mode 100644
index d4262f8971..0000000000
--- a/railties/test/fixtures/about_yml_plugins/plugin_without_about_yml/init.rb
+++ /dev/null
@@ -1 +0,0 @@
-# intentionally empty
\ No newline at end of file
diff --git a/railties/test/fixtures/lib/create_test_dummy_template.rb b/railties/test/fixtures/lib/create_test_dummy_template.rb
index e4378bbd1a..b9eb6a912d 100644
--- a/railties/test/fixtures/lib/create_test_dummy_template.rb
+++ b/railties/test/fixtures/lib/create_test_dummy_template.rb
@@ -1 +1,3 @@
+# frozen_string_literal: true
+
 create_dummy_app("spec/dummy")
diff --git a/railties/test/fixtures/lib/generators/active_record/fixjour_generator.rb b/railties/test/fixtures/lib/generators/active_record/fixjour_generator.rb
index a7d079a1bc..f196971f20 100644
--- a/railties/test/fixtures/lib/generators/active_record/fixjour_generator.rb
+++ b/railties/test/fixtures/lib/generators/active_record/fixjour_generator.rb
@@ -1,4 +1,6 @@
-require 'rails/generators/active_record'
+# frozen_string_literal: true
+
+require "rails/generators/active_record"
 
 module ActiveRecord
   module Generators
diff --git a/railties/test/fixtures/lib/generators/fixjour_generator.rb b/railties/test/fixtures/lib/generators/fixjour_generator.rb
index ef3e9edbed..22197835a8 100644
--- a/railties/test/fixtures/lib/generators/fixjour_generator.rb
+++ b/railties/test/fixtures/lib/generators/fixjour_generator.rb
@@ -1,2 +1,4 @@
+# frozen_string_literal: true
+
 class FixjourGenerator < Rails::Generators::NamedBase
 end
diff --git a/railties/test/fixtures/lib/generators/model_generator.rb b/railties/test/fixtures/lib/generators/model_generator.rb
index 9098a8a354..3009472c3d 100644
--- a/railties/test/fixtures/lib/generators/model_generator.rb
+++ b/railties/test/fixtures/lib/generators/model_generator.rb
@@ -1 +1,3 @@
-raise "I should never be loaded"
\ No newline at end of file
+# frozen_string_literal: true
+
+raise "I should never be loaded"
diff --git a/railties/test/fixtures/lib/generators/usage_template/usage_template_generator.rb b/railties/test/fixtures/lib/generators/usage_template/usage_template_generator.rb
index 078b0f9412..5a847a8bd2 100644
--- a/railties/test/fixtures/lib/generators/usage_template/usage_template_generator.rb
+++ b/railties/test/fixtures/lib/generators/usage_template/usage_template_generator.rb
@@ -1,5 +1,7 @@
-require 'rails/generators'
+# frozen_string_literal: true
+
+require "rails/generators"
 
 class UsageTemplateGenerator < Rails::Generators::Base
-  source_root File.expand_path("templates", File.dirname(__FILE__))
+  source_root File.expand_path("templates", __dir__)
 end
diff --git a/railties/test/fixtures/lib/rails/generators/foobar/foobar_generator.rb b/railties/test/fixtures/lib/rails/generators/foobar/foobar_generator.rb
index d1de8c56fa..159843866c 100644
--- a/railties/test/fixtures/lib/rails/generators/foobar/foobar_generator.rb
+++ b/railties/test/fixtures/lib/rails/generators/foobar/foobar_generator.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module Foobar
   class FoobarGenerator < Rails::Generators::Base
   end
diff --git a/railties/test/fixtures/lib/template.rb b/railties/test/fixtures/lib/template.rb
index c14a1a8784..44083c25e8 100644
--- a/railties/test/fixtures/lib/template.rb
+++ b/railties/test/fixtures/lib/template.rb
@@ -1 +1,3 @@
+# frozen_string_literal: true
+
 say "It works from file!"
diff --git a/railties/test/generators/actions_test.rb b/railties/test/generators/actions_test.rb
index 3b2b3c37d0..f421207025 100644
--- a/railties/test/generators/actions_test.rb
+++ b/railties/test/generators/actions_test.rb
@@ -1,6 +1,8 @@
-require 'generators/generators_test_helper'
-require 'rails/generators/rails/app/app_generator'
-require 'env_helpers'
+# frozen_string_literal: true
+
+require "generators/generators_test_helper"
+require "rails/generators/rails/app/app_generator"
+require "env_helpers"
 
 class ActionsTest < Rails::Generators::TestCase
   include GeneratorsTestHelper
@@ -19,98 +21,105 @@ class ActionsTest < Rails::Generators::TestCase
   end
 
   def test_invoke_other_generator_with_shortcut
-    action :invoke, 'model', ['my_model']
-    assert_file 'app/models/my_model.rb', /MyModel/
+    action :invoke, "model", ["my_model"]
+    assert_file "app/models/my_model.rb", /MyModel/
   end
 
   def test_invoke_other_generator_with_full_namespace
-    action :invoke, 'rails:model', ['my_model']
-    assert_file 'app/models/my_model.rb', /MyModel/
+    action :invoke, "rails:model", ["my_model"]
+    assert_file "app/models/my_model.rb", /MyModel/
   end
 
   def test_create_file_should_write_data_to_file_path
-    action :create_file, 'lib/test_file.rb', 'heres test data'
-    assert_file 'lib/test_file.rb', 'heres test data'
+    action :create_file, "lib/test_file.rb", "heres test data"
+    assert_file "lib/test_file.rb", "heres test data"
   end
 
   def test_create_file_should_write_block_contents_to_file_path
-    action(:create_file, 'lib/test_file.rb'){ 'heres block data' }
-    assert_file 'lib/test_file.rb', 'heres block data'
+    action(:create_file, "lib/test_file.rb") { "heres block data" }
+    assert_file "lib/test_file.rb", "heres block data"
   end
 
   def test_add_source_adds_source_to_gemfile
     run_generator
-    action :add_source, 'http://gems.github.com'
-    assert_file 'Gemfile', /source 'http:\/\/gems\.github\.com'/
+    action :add_source, "http://gems.github.com"
+    assert_file "Gemfile", /source 'http:\/\/gems\.github\.com'/
   end
 
   def test_add_source_with_block_adds_source_to_gemfile_with_gem
     run_generator
-    action :add_source, 'http://gems.github.com' do
-      gem 'rspec-rails'
+    action :add_source, "http://gems.github.com" do
+      gem "rspec-rails"
     end
-    assert_file 'Gemfile', /source 'http:\/\/gems\.github\.com' do\n  gem 'rspec-rails'\nend/
+    assert_file "Gemfile", /source 'http:\/\/gems\.github\.com' do\n  gem 'rspec-rails'\nend/
   end
 
   def test_add_source_with_block_adds_source_to_gemfile_after_gem
     run_generator
-    action :gem, 'will-paginate'
-    action :add_source, 'http://gems.github.com' do
-      gem 'rspec-rails'
+    action :gem, "will-paginate"
+    action :add_source, "http://gems.github.com" do
+      gem "rspec-rails"
     end
-    assert_file 'Gemfile', /gem 'will-paginate'\nsource 'http:\/\/gems\.github\.com' do\n  gem 'rspec-rails'\nend/
+    assert_file "Gemfile", /gem 'will-paginate'\nsource 'http:\/\/gems\.github\.com' do\n  gem 'rspec-rails'\nend/
   end
 
   def test_gem_should_put_gem_dependency_in_gemfile
     run_generator
-    action :gem, 'will-paginate'
-    assert_file 'Gemfile', /gem 'will\-paginate'/
+    action :gem, "will-paginate"
+    assert_file "Gemfile", /gem 'will\-paginate'/
   end
 
   def test_gem_with_version_should_include_version_in_gemfile
     run_generator
-
-    action :gem, 'rspec', '>=2.0.0.a5'
-
-    assert_file 'Gemfile', /gem 'rspec', '>=2.0.0.a5'/
+    action :gem, "rspec", ">= 2.0.0.a5"
+    action :gem, "RedCloth", ">= 4.1.0", "< 4.2.0"
+    action :gem, "nokogiri", version: ">= 1.4.2"
+    action :gem, "faker", version: [">= 0.1.0", "< 0.3.0"]
+
+    assert_file "Gemfile" do |content|
+      assert_match(/gem 'rspec', '>= 2\.0\.0\.a5'/, content)
+      assert_match(/gem 'RedCloth', '>= 4\.1\.0', '< 4\.2\.0'/, content)
+      assert_match(/gem 'nokogiri', '>= 1\.4\.2'/, content)
+      assert_match(/gem 'faker', '>= 0\.1\.0', '< 0\.3\.0'/, content)
+    end
   end
 
   def test_gem_should_insert_on_separate_lines
     run_generator
 
-    File.open('Gemfile', 'a') {|f| f.write('# Some content...') }
+    File.open("Gemfile", "a") { |f| f.write("# Some content...") }
 
-    action :gem, 'rspec'
-    action :gem, 'rspec-rails'
+    action :gem, "rspec"
+    action :gem, "rspec-rails"
 
-    assert_file 'Gemfile', /^gem 'rspec'$/
-    assert_file 'Gemfile', /^gem 'rspec-rails'$/
+    assert_file "Gemfile", /^gem 'rspec'$/
+    assert_file "Gemfile", /^gem 'rspec-rails'$/
   end
 
   def test_gem_should_include_options
     run_generator
 
-    action :gem, 'rspec', github: 'dchelimsky/rspec', tag: '1.2.9.rc1'
+    action :gem, "rspec", github: "dchelimsky/rspec", tag: "1.2.9.rc1"
 
-    assert_file 'Gemfile', /gem 'rspec', github: 'dchelimsky\/rspec', tag: '1\.2\.9\.rc1'/
+    assert_file "Gemfile", /gem 'rspec', github: 'dchelimsky\/rspec', tag: '1\.2\.9\.rc1'/
   end
 
   def test_gem_with_non_string_options
     run_generator
 
-    action :gem, 'rspec', require: false
-    action :gem, 'rspec-rails', group: [:development, :test]
+    action :gem, "rspec", require: false
+    action :gem, "rspec-rails", group: [:development, :test]
 
-    assert_file 'Gemfile', /^gem 'rspec', require: false$/
-    assert_file 'Gemfile', /^gem 'rspec-rails', group: \[:development, :test\]$/
+    assert_file "Gemfile", /^gem 'rspec', require: false$/
+    assert_file "Gemfile", /^gem 'rspec-rails', group: \[:development, :test\]$/
   end
 
   def test_gem_falls_back_to_inspect_if_string_contains_single_quote
     run_generator
 
-    action :gem, 'rspec', ">=2.0'0"
+    action :gem, "rspec", ">=2.0'0"
 
-    assert_file 'Gemfile', /^gem 'rspec', ">=2\.0'0"$/
+    assert_file "Gemfile", /^gem 'rspec', ">=2\.0'0"$/
   end
 
   def test_gem_works_even_if_frozen_string_is_passed_as_argument
@@ -118,115 +127,175 @@ class ActionsTest < Rails::Generators::TestCase
 
     action :gem, "frozen_gem".freeze, "1.0.0".freeze
 
-    assert_file 'Gemfile', /^gem 'frozen_gem', '1.0.0'$/
+    assert_file "Gemfile", /^gem 'frozen_gem', '1.0.0'$/
   end
 
   def test_gem_group_should_wrap_gems_in_a_group
     run_generator
 
     action :gem_group, :development, :test do
-      gem 'rspec-rails'
+      gem "rspec-rails"
     end
 
     action :gem_group, :test do
-      gem 'fakeweb'
+      gem "fakeweb"
     end
 
-    assert_file 'Gemfile', /\ngroup :development, :test do\n  gem 'rspec-rails'\nend\n\ngroup :test do\n  gem 'fakeweb'\nend/
+    assert_file "Gemfile", /\ngroup :development, :test do\n  gem 'rspec-rails'\nend\n\ngroup :test do\n  gem 'fakeweb'\nend/
   end
 
   def test_environment_should_include_data_in_environment_initializer_block
     run_generator
     autoload_paths = 'config.autoload_paths += %w["#{Rails.root}/app/extras"]'
     action :environment, autoload_paths
-    assert_file 'config/application.rb', /  class Application < Rails::Application\n    #{Regexp.escape(autoload_paths)}/
+    assert_file "config/application.rb", /  class Application < Rails::Application\n    #{Regexp.escape(autoload_paths)}\n/
   end
 
   def test_environment_should_include_data_in_environment_initializer_block_with_env_option
     run_generator
     autoload_paths = 'config.autoload_paths += %w["#{Rails.root}/app/extras"]'
-    action :environment, autoload_paths, env: 'development'
-    assert_file "config/environments/development.rb", /Rails\.application\.configure do\n  #{Regexp.escape(autoload_paths)}/
+    action :environment, autoload_paths, env: "development"
+    assert_file "config/environments/development.rb", /Rails\.application\.configure do\n  #{Regexp.escape(autoload_paths)}\n/
   end
 
   def test_environment_with_block_should_include_block_contents_in_environment_initializer_block
     run_generator
 
     action :environment do
-      _ = '# This wont be added'# assignment to silence parse-time warning "unused literal ignored"
-      '# This will be added'
+      _ = "# This wont be added"# assignment to silence parse-time warning "unused literal ignored"
+      "# This will be added"
     end
 
-    assert_file 'config/application.rb' do |content|
+    assert_file "config/application.rb" do |content|
       assert_match(/# This will be added/, content)
       assert_no_match(/# This wont be added/, content)
     end
   end
 
+  def test_environment_with_block_should_include_block_contents_with_multiline_data_in_environment_initializer_block
+    run_generator
+    data = <<-RUBY
+      config.encoding = "utf-8"
+      config.time_zone = "UTC"
+    RUBY
+    action(:environment) { data }
+    assert_file "config/application.rb", /  class Application < Rails::Application\n#{Regexp.escape(data.strip_heredoc.indent(4))}/
+  end
+
+  def test_environment_should_include_block_contents_with_multiline_data_in_environment_initializer_block_with_env_option
+    run_generator
+    data = <<-RUBY
+      config.encoding = "utf-8"
+      config.time_zone = "UTC"
+    RUBY
+    action(:environment, nil, env: "development") { data }
+    assert_file "config/environments/development.rb", /Rails\.application\.configure do\n#{Regexp.escape(data.strip_heredoc.indent(2))}/
+  end
+
   def test_git_with_symbol_should_run_command_using_git_scm
-    assert_called_with(generator, :run, ['git init']) do
+    assert_called_with(generator, :run, ["git init"]) do
       action :git, :init
     end
   end
 
   def test_git_with_hash_should_run_each_command_using_git_scm
     assert_called_with(generator, :run, [ ["git rm README"], ["git add ."] ]) do
-      action :git, rm: 'README', add: '.'
+      action :git, rm: "README", add: "."
     end
   end
 
   def test_vendor_should_write_data_to_file_in_vendor
-    action :vendor, 'vendor_file.rb', '# vendor data'
-    assert_file 'vendor/vendor_file.rb', '# vendor data'
+    action :vendor, "vendor_file.rb", "# vendor data"
+    assert_file "vendor/vendor_file.rb", "# vendor data\n"
+  end
+
+  def test_vendor_should_write_data_to_file_with_block_in_vendor
+    code = <<-RUBY
+      puts "one"
+      puts "two"
+      puts "three"
+    RUBY
+    action(:vendor, "vendor_file.rb") { code }
+    assert_file "vendor/vendor_file.rb", code.strip_heredoc
   end
 
   def test_lib_should_write_data_to_file_in_lib
-    action :lib, 'my_library.rb', 'class MyLibrary'
-    assert_file 'lib/my_library.rb', 'class MyLibrary'
+    action :lib, "my_library.rb", "class MyLibrary"
+    assert_file "lib/my_library.rb", "class MyLibrary\n"
+  end
+
+  def test_lib_should_write_data_to_file_with_block_in_lib
+    code = <<-RUBY
+      class MyLib
+        MY_CONSTANT = 123
+      end
+    RUBY
+    action(:lib, "my_library.rb") { code }
+    assert_file "lib/my_library.rb", code.strip_heredoc
   end
 
   def test_rakefile_should_write_date_to_file_in_lib_tasks
-    action :rakefile, 'myapp.rake', 'task run: [:environment]'
-    assert_file 'lib/tasks/myapp.rake', 'task run: [:environment]'
+    action :rakefile, "myapp.rake", "task run: [:environment]"
+    assert_file "lib/tasks/myapp.rake", "task run: [:environment]\n"
+  end
+
+  def test_rakefile_should_write_date_to_file_with_block_in_lib_tasks
+    code = <<-RUBY
+      task rock: :environment do
+        puts "Rockin'"
+      end
+    RUBY
+    action(:rakefile, "myapp.rake") { code }
+    assert_file "lib/tasks/myapp.rake", code.strip_heredoc
   end
 
   def test_initializer_should_write_date_to_file_in_config_initializers
-    action :initializer, 'constants.rb', 'MY_CONSTANT = 42'
-    assert_file 'config/initializers/constants.rb', 'MY_CONSTANT = 42'
+    action :initializer, "constants.rb", "MY_CONSTANT = 42"
+    assert_file "config/initializers/constants.rb", "MY_CONSTANT = 42\n"
+  end
+
+  def test_initializer_should_write_date_to_file_with_block_in_config_initializers
+    code = <<-RUBY
+      MyLib.configure do |config|
+        config.value = 123
+      end
+    RUBY
+    action(:initializer, "constants.rb") { code }
+    assert_file "config/initializers/constants.rb", code.strip_heredoc
   end
 
   def test_generate_should_run_script_generate_with_argument_and_options
-    assert_called_with(generator, :run_ruby_script, ['bin/rails generate model MyModel', verbose: false]) do
-      action :generate, 'model', 'MyModel'
+    assert_called_with(generator, :run_ruby_script, ["bin/rails generate model MyModel", verbose: false]) do
+      action :generate, "model", "MyModel"
     end
   end
 
   def test_rails_should_run_rake_command_with_default_env
     assert_called_with(generator, :run, ["rake log:clear RAILS_ENV=development", verbose: false]) do
       with_rails_env nil do
-        action :rake, 'log:clear'
+        action :rake, "log:clear"
       end
     end
   end
 
   def test_rails_with_env_option_should_run_rake_command_in_env
-    assert_called_with(generator, :run, ['rake log:clear RAILS_ENV=production', verbose: false]) do
-      action :rake, 'log:clear', env: 'production'
+    assert_called_with(generator, :run, ["rake log:clear RAILS_ENV=production", verbose: false]) do
+      action :rake, "log:clear", env: "production"
     end
   end
 
   test "rails command with RAILS_ENV variable should run rake command in env" do
-    assert_called_with(generator, :run, ['rake log:clear RAILS_ENV=production', verbose: false]) do
+    assert_called_with(generator, :run, ["rake log:clear RAILS_ENV=production", verbose: false]) do
       with_rails_env "production" do
-        action :rake, 'log:clear'
+        action :rake, "log:clear"
       end
     end
   end
 
   test "env option should win over RAILS_ENV variable when running rake" do
-    assert_called_with(generator, :run, ['rake log:clear RAILS_ENV=production', verbose: false]) do
+    assert_called_with(generator, :run, ["rake log:clear RAILS_ENV=production", verbose: false]) do
       with_rails_env "staging" do
-        action :rake, 'log:clear', env: 'production'
+        action :rake, "log:clear", env: "production"
       end
     end
   end
@@ -234,7 +303,15 @@ class ActionsTest < Rails::Generators::TestCase
   test "rails command with sudo option should run rake command with sudo" do
     assert_called_with(generator, :run, ["sudo rake log:clear RAILS_ENV=development", verbose: false]) do
       with_rails_env nil do
-        action :rake, 'log:clear', sudo: true
+        action :rake, "log:clear", sudo: true
+      end
+    end
+  end
+
+  test "rake command with capture option should run rake command with capture" do
+    assert_called_with(generator, :run, ["rake log:clear RAILS_ENV=development", verbose: false, capture: true]) do
+      with_rails_env nil do
+        action :rake, "log:clear", capture: true
       end
     end
   end
@@ -242,29 +319,29 @@ class ActionsTest < Rails::Generators::TestCase
   test "rails command should run rails_command with default env" do
     assert_called_with(generator, :run, ["rails log:clear RAILS_ENV=development", verbose: false]) do
       with_rails_env nil do
-        action :rails_command, 'log:clear'
+        action :rails_command, "log:clear"
       end
     end
   end
 
   test "rails command with env option should run rails_command with same env" do
-    assert_called_with(generator, :run, ['rails log:clear RAILS_ENV=production', verbose: false]) do
-      action :rails_command, 'log:clear', env: 'production'
+    assert_called_with(generator, :run, ["rails log:clear RAILS_ENV=production", verbose: false]) do
+      action :rails_command, "log:clear", env: "production"
     end
   end
 
   test "rails command with RAILS_ENV variable should run rails_command in env" do
-    assert_called_with(generator, :run, ['rails log:clear RAILS_ENV=production', verbose: false]) do
+    assert_called_with(generator, :run, ["rails log:clear RAILS_ENV=production", verbose: false]) do
       with_rails_env "production" do
-        action :rails_command, 'log:clear'
+        action :rails_command, "log:clear"
       end
     end
   end
 
   def test_env_option_should_win_over_rails_env_variable_when_running_rails
-    assert_called_with(generator, :run, ['rails log:clear RAILS_ENV=production', verbose: false]) do
+    assert_called_with(generator, :run, ["rails log:clear RAILS_ENV=production", verbose: false]) do
       with_rails_env "staging" do
-        action :rails_command, 'log:clear', env: 'production'
+        action :rails_command, "log:clear", env: "production"
       end
     end
   end
@@ -272,27 +349,38 @@ class ActionsTest < Rails::Generators::TestCase
   test "rails command with sudo option should run rails_command with sudo" do
     assert_called_with(generator, :run, ["sudo rails log:clear RAILS_ENV=development", verbose: false]) do
       with_rails_env nil do
-        action :rails_command, 'log:clear', sudo: true
+        action :rails_command, "log:clear", sudo: true
+      end
+    end
+  end
+
+  test "rails command with capture option should run rails_command with capture" do
+    assert_called_with(generator, :run, ["rails log:clear RAILS_ENV=development", verbose: false, capture: true]) do
+      with_rails_env nil do
+        action :rails_command, "log:clear", capture: true
       end
     end
   end
 
   def test_capify_should_run_the_capify_command
-    assert_called_with(generator, :run, ['capify .', verbose: false]) do
-      action :capify!
+    content = capture(:stderr) do
+      assert_called_with(generator, :run, ["capify .", verbose: false]) do
+        action :capify!
+      end
     end
+    assert_match(/DEPRECATION WARNING: `capify!` is deprecated/, content)
   end
 
   def test_route_should_add_data_to_the_routes_block_in_config_routes
     run_generator
     route_command = "route '/login', controller: 'sessions', action: 'new'"
     action :route, route_command
-    assert_file 'config/routes.rb', /#{Regexp.escape(route_command)}/
+    assert_file "config/routes.rb", /#{Regexp.escape(route_command)}/
   end
 
   def test_route_should_be_idempotent
     run_generator
-    route_path = File.expand_path('config/routes.rb', destination_root)
+    route_path = File.expand_path("config/routes.rb", destination_root)
 
     # runs first time, not asserting
     action :route, "root 'welcome#index'"
@@ -312,8 +400,8 @@ class ActionsTest < Rails::Generators::TestCase
     content = File.read(route_path)
 
     # Remove all of the comments and blank lines from the routes file
-    content.gsub!(/^  \#.*\n/, '')
-    content.gsub!(/^\n/, '')
+    content.gsub!(/^  \#.*\n/, "")
+    content.gsub!(/^\n/, "")
 
     File.open(route_path, "wb") { |file| file.write(content) }
 
@@ -369,10 +457,9 @@ F
     assert_equal("", action(:log, :yes, "YES"))
   end
 
-  protected
+  private
 
     def action(*args, &block)
-      capture(:stdout){ generator.send(*args, &block) }
+      capture(:stdout) { generator.send(*args, &block) }
     end
-
 end
diff --git a/railties/test/generators/api_app_generator_test.rb b/railties/test/generators/api_app_generator_test.rb
index 92779452e1..4815cf6362 100644
--- a/railties/test/generators/api_app_generator_test.rb
+++ b/railties/test/generators/api_app_generator_test.rb
@@ -1,11 +1,13 @@
-require 'generators/generators_test_helper'
-require 'rails/generators/rails/app/app_generator'
+# frozen_string_literal: true
+
+require "generators/generators_test_helper"
+require "rails/generators/rails/app/app_generator"
 
 class ApiAppGeneratorTest < Rails::Generators::TestCase
   include GeneratorsTestHelper
   tests Rails::Generators::AppGenerator
 
-  arguments [destination_root, '--api']
+  arguments [destination_root, "--api"]
 
   def setup
     Rails.application = TestApp::Application
@@ -33,27 +35,26 @@ class ApiAppGeneratorTest < Rails::Generators::TestCase
   def test_api_modified_files
     run_generator
 
+    assert_file ".gitignore" do |content|
+      assert_no_match(/\/public\/assets/, content)
+    end
+
     assert_file "Gemfile" do |content|
       assert_no_match(/gem 'coffee-rails'/, content)
-      assert_no_match(/gem 'jquery-rails'/, content)
       assert_no_match(/gem 'sass-rails'/, content)
       assert_no_match(/gem 'web-console'/, content)
+      assert_no_match(/gem 'capybara'/, content)
+      assert_no_match(/gem 'selenium-webdriver'/, content)
       assert_match(/# gem 'jbuilder'/, content)
+      assert_match(/# gem 'rack-cors'/, content)
     end
 
-    assert_file "config/application.rb" do |content|
-      assert_match(/config.api_only = true/, content)
-    end
-
-    assert_file "config/initializers/cors.rb"
-
-    assert_file "config/initializers/wrap_parameters.rb"
-
+    assert_file "config/application.rb", /config\.api_only = true/
     assert_file "app/controllers/application_controller.rb", /ActionController::API/
   end
 
   def test_generator_if_skip_action_cable_is_given
-    run_generator [destination_root, "--skip-action-cable"]
+    run_generator [destination_root, "--api", "--skip-action-cable"]
     assert_file "config/application.rb", /#\s+require\s+["']action_cable\/engine["']/
     assert_no_file "config/cable.yml"
     assert_no_file "app/channels"
@@ -62,62 +63,104 @@ class ApiAppGeneratorTest < Rails::Generators::TestCase
     end
   end
 
-  def test_generator_skips_per_form_csrf_token_and_origin_check_configs_for_api_apps
+  def test_app_update_does_not_generate_unnecessary_config_files
     run_generator
 
-    assert_file "config/initializers/new_framework_defaults.rb" do |initializer_content|
-      assert_no_match(/per_form_csrf_tokens/, initializer_content)
-      assert_no_match(/forgery_protection_origin_check/, initializer_content)
-    end
+    generator = Rails::Generators::AppGenerator.new ["rails"],
+      { api: true, update: true }, { destination_root: destination_root, shell: @shell }
+    quietly { generator.send(:update_config_files) }
+
+    assert_no_file "config/initializers/cookies_serializer.rb"
+    assert_no_file "config/initializers/assets.rb"
+    assert_no_file "config/initializers/content_security_policy.rb"
   end
 
-  private
+  def test_app_update_does_not_generate_unnecessary_bin_files
+    run_generator
 
-  def default_files
-    files = %W(
-      .gitignore
-      Gemfile
-      Rakefile
-      config.ru
-      app/controllers
-      app/mailers
-      app/models
-      app/views/layouts/mailer.html.erb
-      app/views/layouts/mailer.text.erb
-      config/environments
-      config/initializers
-      config/locales
-      db
-      lib
-      lib/tasks
-      log
-      test/fixtures
-      test/controllers
-      test/integration
-      test/models
-      tmp
-      vendor
-    )
-    files.concat %w(bin/bundle bin/rails bin/rake)
-    files
-  end
+    generator = Rails::Generators::AppGenerator.new ["rails"],
+      { api: true, update: true }, { destination_root: destination_root, shell: @shell }
+    quietly { generator.send(:update_bin_files) }
 
-  def skipped_files
-    %w(app/assets
-       app/helpers
-       app/views/layouts/application.html.erb
-       config/initializers/assets.rb
-       config/initializers/cookies_serializer.rb
-       config/initializers/session_store.rb
-       lib/assets
-       vendor/assets
-       test/helpers
-       tmp/cache/assets
-       public/404.html
-       public/422.html
-       public/500.html
-       public/apple-touch-icon-precomposed.png
-       public/apple-touch-icon.png
-       public/favicon.ico)
+    assert_no_file "bin/yarn"
   end
+
+  private
+
+    def default_files
+      %w(.gitignore
+        .ruby-version
+        README.md
+        Gemfile
+        Rakefile
+        config.ru
+        app/channels
+        app/controllers
+        app/mailers
+        app/models
+        app/views/layouts
+        app/views/layouts/mailer.html.erb
+        app/views/layouts/mailer.text.erb
+        bin/bundle
+        bin/rails
+        bin/rake
+        bin/setup
+        bin/update
+        config/application.rb
+        config/boot.rb
+        config/cable.yml
+        config/environment.rb
+        config/environments
+        config/environments/development.rb
+        config/environments/production.rb
+        config/environments/test.rb
+        config/initializers
+        config/initializers/application_controller_renderer.rb
+        config/initializers/backtrace_silencers.rb
+        config/initializers/cors.rb
+        config/initializers/filter_parameter_logging.rb
+        config/initializers/inflections.rb
+        config/initializers/mime_types.rb
+        config/initializers/wrap_parameters.rb
+        config/locales
+        config/locales/en.yml
+        config/puma.rb
+        config/routes.rb
+        config/credentials.yml.enc
+        config/spring.rb
+        config/storage.yml
+        db
+        db/seeds.rb
+        lib
+        lib/tasks
+        log
+        test/fixtures
+        test/controllers
+        test/integration
+        test/models
+        tmp
+        vendor
+      )
+    end
+
+    def skipped_files
+      %w(app/assets
+         app/helpers
+         app/views/layouts/application.html.erb
+         bin/yarn
+         config/initializers/assets.rb
+         config/initializers/cookies_serializer.rb
+         config/initializers/content_security_policy.rb
+         lib/assets
+         test/helpers
+         tmp/cache/assets
+         public/404.html
+         public/422.html
+         public/500.html
+         public/apple-touch-icon-precomposed.png
+         public/apple-touch-icon.png
+         public/favicon.ico
+         package.json
+      )
+    end
 end
diff --git a/railties/test/generators/app_generator_test.rb b/railties/test/generators/app_generator_test.rb
index 058308aa13..fcb515c606 100644
--- a/railties/test/generators/app_generator_test.rb
+++ b/railties/test/generators/app_generator_test.rb
@@ -1,39 +1,83 @@
-require 'generators/generators_test_helper'
-require 'rails/generators/rails/app/app_generator'
-require 'generators/shared_generator_tests'
+# frozen_string_literal: true
+
+require "generators/generators_test_helper"
+require "rails/generators/rails/app/app_generator"
+require "generators/shared_generator_tests"
 
 DEFAULT_APP_FILES = %w(
   .gitignore
+  .ruby-version
   README.md
   Gemfile
   Rakefile
   config.ru
+  app/assets/config/manifest.js
+  app/assets/images
   app/assets/javascripts
+  app/assets/javascripts/application.js
+  app/assets/javascripts/cable.js
+  app/assets/javascripts/channels
   app/assets/stylesheets
-  app/assets/images
+  app/assets/stylesheets/application.css
+  app/channels/application_cable/channel.rb
+  app/channels/application_cable/connection.rb
   app/controllers
+  app/controllers/application_controller.rb
   app/controllers/concerns
   app/helpers
+  app/helpers/application_helper.rb
   app/mailers
+  app/mailers/application_mailer.rb
   app/models
+  app/models/application_record.rb
   app/models/concerns
   app/jobs
+  app/jobs/application_job.rb
   app/views/layouts
+  app/views/layouts/application.html.erb
+  app/views/layouts/mailer.html.erb
+  app/views/layouts/mailer.text.erb
   bin/bundle
   bin/rails
   bin/rake
   bin/setup
+  bin/update
+  bin/yarn
+  config/application.rb
+  config/boot.rb
+  config/cable.yml
+  config/environment.rb
   config/environments
+  config/environments/development.rb
+  config/environments/production.rb
+  config/environments/test.rb
   config/initializers
+  config/initializers/application_controller_renderer.rb
+  config/initializers/assets.rb
+  config/initializers/backtrace_silencers.rb
+  config/initializers/cookies_serializer.rb
+  config/initializers/content_security_policy.rb
+  config/initializers/filter_parameter_logging.rb
+  config/initializers/inflections.rb
+  config/initializers/mime_types.rb
+  config/initializers/wrap_parameters.rb
   config/locales
-  config/cable.yml
+  config/locales/en.yml
   config/puma.rb
+  config/routes.rb
+  config/credentials.yml.enc
   config/spring.rb
+  config/storage.yml
   db
+  db/seeds.rb
   lib
   lib/tasks
   lib/assets
   log
+  package.json
+  public
+  storage
+  test/application_system_test_case.rb
   test/test_helper.rb
   test/fixtures
   test/fixtures/files
@@ -42,13 +86,12 @@ DEFAULT_APP_FILES = %w(
   test/helpers
   test/mailers
   test/integration
+  test/system
   vendor
-  vendor/assets
-  vendor/assets/stylesheets
-  vendor/assets/javascripts
   tmp
   tmp/cache
   tmp/cache/assets
+  tmp/storage
 )
 
 class AppGeneratorTest < Rails::Generators::TestCase
@@ -62,6 +105,15 @@ class AppGeneratorTest < Rails::Generators::TestCase
     ::DEFAULT_APP_FILES
   end
 
+  def test_skip_bundle
+    assert_not_called(generator([destination_root], skip_bundle: true), :bundle_command) do
+      quietly { generator.invoke_all }
+      # skip_bundle is only about running bundle install, ensure the Gemfile is still
+      # generated.
+      assert_file "Gemfile"
+    end
+  end
+
   def test_assets
     run_generator
 
@@ -77,7 +129,7 @@ class AppGeneratorTest < Rails::Generators::TestCase
   end
 
   def test_invalid_application_name_raises_an_error
-    content = capture(:stderr){ run_generator [File.join(destination_root, "43-things")] }
+    content = capture(:stderr) { run_generator [File.join(destination_root, "43-things")] }
     assert_equal "Invalid application name 43-things. Please give a name which does not start with numbers.\n", content
   end
 
@@ -88,12 +140,12 @@ class AppGeneratorTest < Rails::Generators::TestCase
   end
 
   def test_application_new_exits_with_non_zero_code_on_invalid_application_name
-    quietly { system 'rails new test --no-rc' }
+    quietly { system "rails new test --no-rc" }
     assert_equal false, $?.success?
   end
 
   def test_application_new_exits_with_message_and_non_zero_code_when_generating_inside_existing_rails_directory
-    app_root = File.join(destination_root, 'myfirstapp')
+    app_root = File.join(destination_root, "myfirstapp")
     run_generator [app_root]
     output = nil
     Dir.chdir(app_root) do
@@ -104,7 +156,7 @@ class AppGeneratorTest < Rails::Generators::TestCase
   end
 
   def test_application_new_show_help_message_inside_existing_rails_directory
-    app_root = File.join(destination_root, 'myfirstapp')
+    app_root = File.join(destination_root, "myfirstapp")
     run_generator [app_root]
     output = Dir.chdir(app_root) do
       `rails new --help`
@@ -131,20 +183,18 @@ class AppGeneratorTest < Rails::Generators::TestCase
         generator.send(:app_const)
         quietly { generator.send(:update_config_files) }
         assert_file "myapp_moved/config/environment.rb", /Rails\.application\.initialize!/
-        assert_file "myapp_moved/config/initializers/session_store.rb", /_myapp_session/
       end
     end
   end
 
-  def test_rails_update_generates_correct_session_key
-    app_root = File.join(destination_root, 'myapp')
+  def test_app_update_generates_correct_session_key
+    app_root = File.join(destination_root, "myapp")
     run_generator [app_root]
 
     stub_rails_application(app_root) do
       generator = Rails::Generators::AppGenerator.new ["rails"], [], destination_root: app_root, shell: @shell
       generator.send(:app_const)
       quietly { generator.send(:update_config_files) }
-      assert_file "myapp/config/initializers/session_store.rb", /_myapp_session/
     end
   end
 
@@ -157,71 +207,69 @@ class AppGeneratorTest < Rails::Generators::TestCase
   def test_new_application_not_include_api_initializers
     run_generator
 
-    assert_no_file 'config/initializers/cors.rb'
+    assert_no_file "config/initializers/cors.rb"
+  end
+
+  def test_new_application_doesnt_need_defaults
+    assert_no_file "config/initializers/new_framework_defaults_5_2.rb"
   end
 
-  def test_rails_update_keep_the_cookie_serializer_if_it_is_already_configured
-    app_root = File.join(destination_root, 'myapp')
+  def test_new_application_load_defaults
+    app_root = File.join(destination_root, "myfirstapp")
     run_generator [app_root]
+    output = nil
 
-    stub_rails_application(app_root) do
-      generator = Rails::Generators::AppGenerator.new ["rails"], [], destination_root: app_root, shell: @shell
-      generator.send(:app_const)
-      quietly { generator.send(:update_config_files) }
-      assert_file("#{app_root}/config/initializers/cookies_serializer.rb", /Rails\.application\.config\.action_dispatch\.cookies_serializer = :json/)
+    Dir.chdir(app_root) do
+      output = `./bin/rails r "puts Rails.application.config.assets.unknown_asset_fallback"`
     end
+
+    assert_equal "false\n", output
   end
 
-  def test_rails_update_set_the_cookie_serializer_to_marshal_if_it_is_not_already_configured
-    app_root = File.join(destination_root, 'myapp')
+  def test_app_update_keep_the_cookie_serializer_if_it_is_already_configured
+    app_root = File.join(destination_root, "myapp")
     run_generator [app_root]
 
-    FileUtils.rm("#{app_root}/config/initializers/cookies_serializer.rb")
-
     stub_rails_application(app_root) do
       generator = Rails::Generators::AppGenerator.new ["rails"], [], destination_root: app_root, shell: @shell
       generator.send(:app_const)
       quietly { generator.send(:update_config_files) }
-      assert_file("#{app_root}/config/initializers/cookies_serializer.rb",
-                  /Valid options are :json, :marshal, and :hybrid\.\nRails\.application\.config\.action_dispatch\.cookies_serializer = :marshal/)
+      assert_file("#{app_root}/config/initializers/cookies_serializer.rb", /Rails\.application\.config\.action_dispatch\.cookies_serializer = :json/)
     end
   end
 
-  def test_rails_update_dont_set_file_watcher
-    app_root = File.join(destination_root, 'myapp')
+  def test_app_update_set_the_cookie_serializer_to_marshal_if_it_is_not_already_configured
+    app_root = File.join(destination_root, "myapp")
     run_generator [app_root]
 
+    FileUtils.rm("#{app_root}/config/initializers/cookies_serializer.rb")
+
     stub_rails_application(app_root) do
       generator = Rails::Generators::AppGenerator.new ["rails"], [], destination_root: app_root, shell: @shell
       generator.send(:app_const)
       quietly { generator.send(:update_config_files) }
-      assert_file "#{app_root}/config/environments/development.rb" do |content|
-        assert_match(/# config.file_watcher/, content)
-      end
+      assert_file("#{app_root}/config/initializers/cookies_serializer.rb",
+                  /Valid options are :json, :marshal, and :hybrid\.\nRails\.application\.config\.action_dispatch\.cookies_serializer = :marshal/)
     end
   end
 
-  def test_rails_update_does_not_create_new_framework_defaults_by_default
-    app_root = File.join(destination_root, 'myapp')
+  def test_app_update_create_new_framework_defaults
+    app_root = File.join(destination_root, "myapp")
     run_generator [app_root]
 
-    FileUtils.rm("#{app_root}/config/initializers/new_framework_defaults.rb")
+    assert_no_file "#{app_root}/config/initializers/new_framework_defaults_5_2.rb"
 
     stub_rails_application(app_root) do
-      generator = Rails::Generators::AppGenerator.new ["rails"], { update: true }, destination_root: app_root, shell: @shell
+      generator = Rails::Generators::AppGenerator.new ["rails"], { update: true }, { destination_root: app_root, shell: @shell }
       generator.send(:app_const)
       quietly { generator.send(:update_config_files) }
 
-      assert_file "#{app_root}/config/initializers/new_framework_defaults.rb" do |content|
-        assert_match(/ActiveSupport\.halt_callback_chains_on_return_false = true/, content)
-        assert_match(/Rails\.application\.config.active_record\.belongs_to_required_by_default = false/, content)
-        assert_no_match(/Rails\.application\.config\.ssl_options/, content)
-      end
+      assert_file "#{app_root}/config/initializers/new_framework_defaults_5_2.rb"
     end
   end
 
-  def test_rails_update_does_not_create_rack_cors
-    app_root = File.join(destination_root, 'myapp')
+  def test_app_update_does_not_create_rack_cors
+    app_root = File.join(destination_root, "myapp")
     run_generator [app_root]
 
     stub_rails_application(app_root) do
@@ -232,8 +280,8 @@ class AppGeneratorTest < Rails::Generators::TestCase
     end
   end
 
-  def test_rails_update_does_not_remove_rack_cors_if_already_present
-    app_root = File.join(destination_root, 'myapp')
+  def test_app_update_does_not_remove_rack_cors_if_already_present
+    app_root = File.join(destination_root, "myapp")
     run_generator [app_root]
 
     FileUtils.touch("#{app_root}/config/initializers/cors.rb")
@@ -246,6 +294,96 @@ class AppGeneratorTest < Rails::Generators::TestCase
     end
   end
 
+  def test_app_update_does_not_generate_action_cable_contents_when_skip_action_cable_is_given
+    app_root = File.join(destination_root, "myapp")
+    run_generator [app_root, "--skip-action-cable"]
+
+    FileUtils.cd(app_root) do
+      quietly { system("bin/rails app:update") }
+    end
+
+    assert_no_file "#{app_root}/config/cable.yml"
+    assert_file "#{app_root}/config/environments/production.rb" do |content|
+      assert_no_match(/config\.action_cable/, content)
+    end
+  end
+
+  def test_active_storage_mini_magick_gem
+    run_generator
+    assert_file "Gemfile", /^# gem 'mini_magick'/
+  end
+
+  def test_active_storage_install
+    command_check = -> command, _ do
+      @binstub_called ||= 0
+      case command
+      when "active_storage:install"
+        @binstub_called += 1
+        assert_equal 1, @binstub_called, "active_storage:install expected to be called once, but was called #{@binstub_called} times"
+      end
+    end
+
+    generator.stub :rails_command, command_check do
+      generator.stub :bundle_command, nil do
+        quietly { generator.invoke_all }
+      end
+    end
+  end
+
+  def test_app_update_does_not_generate_active_storage_contents_when_skip_active_storage_is_given
+    app_root = File.join(destination_root, "myapp")
+    run_generator [app_root, "--skip-active-storage"]
+
+    FileUtils.cd(app_root) do
+      quietly { system("bin/rails app:update") }
+    end
+
+    assert_file "#{app_root}/config/environments/development.rb" do |content|
+      assert_no_match(/config\.active_storage/, content)
+    end
+
+    assert_file "#{app_root}/config/environments/production.rb" do |content|
+      assert_no_match(/config\.active_storage/, content)
+    end
+
+    assert_file "#{app_root}/config/environments/test.rb" do |content|
+      assert_no_match(/config\.active_storage/, content)
+    end
+
+    assert_no_file "#{app_root}/config/storage.yml"
+
+    assert_file "#{app_root}/Gemfile" do |content|
+      assert_no_match(/gem 'mini_magick'/, content)
+    end
+  end
+
+  def test_app_update_does_not_generate_active_storage_contents_when_skip_active_record_is_given
+    app_root = File.join(destination_root, "myapp")
+    run_generator [app_root, "--skip-active-record"]
+
+    FileUtils.cd(app_root) do
+      quietly { system("bin/rails app:update") }
+    end
+
+    assert_file "#{app_root}/config/environments/development.rb" do |content|
+      assert_no_match(/config\.active_storage/, content)
+    end
+
+    assert_file "#{app_root}/config/environments/production.rb" do |content|
+      assert_no_match(/config\.active_storage/, content)
+    end
+
+    assert_file "#{app_root}/config/environments/test.rb" do |content|
+      assert_no_match(/config\.active_storage/, content)
+    end
+
+    assert_no_file "#{app_root}/config/storage.yml"
+
+    assert_file "#{app_root}/Gemfile" do |content|
+      assert_no_match(/gem 'mini_magick'/, content)
+    end
+  end
+
   def test_application_names_are_not_singularized
     run_generator [File.join(destination_root, "hats")]
     assert_file "hats/config/environment.rb", /Rails\.application\.initialize!/
@@ -254,7 +392,7 @@ class AppGeneratorTest < Rails::Generators::TestCase
   def test_gemfile_has_no_whitespace_errors
     run_generator
     absolute = File.expand_path("Gemfile", destination_root)
-    File.open(absolute, 'r') do |f|
+    File.open(absolute, "r") do |f|
       f.each_line do |line|
         assert_no_match %r{/^[ \t]+$/}, line
       end
@@ -277,7 +415,7 @@ class AppGeneratorTest < Rails::Generators::TestCase
     if defined?(JRUBY_VERSION)
       assert_gem "activerecord-jdbcmysql-adapter"
     else
-      assert_gem "mysql2", "'>= 0.3.18', '< 0.5'"
+      assert_gem "mysql2", "'~> 0.4.4'"
     end
   end
 
@@ -329,23 +467,9 @@ class AppGeneratorTest < Rails::Generators::TestCase
     end
   end
 
-  def test_generator_without_skips
-    run_generator
-    assert_file "config/application.rb", /\s+require\s+["']rails\/all["']/
-    assert_file "config/environments/development.rb" do |content|
-      assert_match(/config\.action_mailer\.raise_delivery_errors = false/, content)
-    end
-    assert_file "config/environments/test.rb" do |content|
-      assert_match(/config\.action_mailer\.delivery_method = :test/, content)
-    end
-    assert_file "config/environments/production.rb" do |content|
-      assert_match(/# config\.action_mailer\.raise_delivery_errors = false/, content)
-    end
-  end
-
   def test_generator_defaults_to_puma_version
     run_generator [destination_root]
-    assert_gem "puma", "'~> 3.0'"
+    assert_gem "puma", "'~> 3.11'"
   end
 
   def test_generator_if_skip_puma_is_given
@@ -356,111 +480,78 @@ class AppGeneratorTest < Rails::Generators::TestCase
     end
   end
 
-  def test_generator_if_skip_active_record_is_given
-    run_generator [destination_root, "--skip-active-record"]
-    assert_no_file "config/database.yml"
-    assert_no_file "app/models/application_record.rb"
-    assert_file "config/application.rb", /#\s+require\s+["']active_record\/railtie["']/
-    assert_file "test/test_helper.rb" do |helper_content|
-      assert_no_match(/fixtures :all/, helper_content)
-    end
+  def test_generator_has_assets_gems
+    run_generator
 
-    assert_file "config/initializers/new_framework_defaults.rb" do |initializer_content|
-      assert_no_match(/belongs_to_required_by_default/, initializer_content)
-    end
+    assert_gem "sass-rails"
+    assert_gem "uglifier"
   end
 
-  def test_generator_if_skip_action_mailer_is_given
-    run_generator [destination_root, "--skip-action-mailer"]
-    assert_file "config/application.rb", /#\s+require\s+["']action_mailer\/railtie["']/
-    assert_file "config/environments/development.rb" do |content|
-      assert_no_match(/config\.action_mailer/, content)
-    end
-    assert_file "config/environments/test.rb" do |content|
-      assert_no_match(/config\.action_mailer/, content)
-    end
-    assert_file "config/environments/production.rb" do |content|
-      assert_no_match(/config\.action_mailer/, content)
-    end
+  def test_action_cable_redis_gems
+    run_generator
+    assert_file "Gemfile", /^# gem 'redis'/
   end
 
-  def test_generator_has_assets_gems
-    run_generator
+  def test_generator_if_skip_test_is_given
+    run_generator [destination_root, "--skip-test"]
 
-    assert_gem 'sass-rails'
-    assert_gem 'uglifier'
-  end
+    assert_file "config/application.rb", /#\s+require\s+["']rails\/test_unit\/railtie["']/
 
-  def test_generator_if_skip_sprockets_is_given
-    run_generator [destination_root, "--skip-sprockets"]
-    assert_no_file "config/initializers/assets.rb"
-    assert_file "config/application.rb" do |content|
-      assert_match(/#\s+require\s+["']sprockets\/railtie["']/, content)
-    end
     assert_file "Gemfile" do |content|
-      assert_no_match(/jquery-rails/, content)
-      assert_no_match(/sass-rails/, content)
-      assert_no_match(/uglifier/, content)
-      assert_no_match(/coffee-rails/, content)
-    end
-    assert_file "config/environments/development.rb" do |content|
-      assert_no_match(/config\.assets\.debug = true/, content)
-    end
-    assert_file "config/environments/production.rb" do |content|
-      assert_no_match(/config\.assets\.digest = true/, content)
-      assert_no_match(/config\.assets\.js_compressor = :uglifier/, content)
-      assert_no_match(/config\.assets\.css_compressor = :sass/, content)
+      assert_no_match(/capybara/, content)
+      assert_no_match(/selenium-webdriver/, content)
+      assert_no_match(/chromedriver-helper/, content)
     end
+
+    assert_no_directory("test")
   end
 
-  def test_generator_if_skip_action_cable_is_given
-    run_generator [destination_root, "--skip-action-cable"]
-    assert_file "config/application.rb", /#\s+require\s+["']action_cable\/engine["']/
-    assert_no_file "config/cable.yml"
-    assert_no_file "app/assets/javascripts/cable.js"
-    assert_no_file "app/channels"
+  def test_generator_if_skip_system_test_is_given
+    run_generator [destination_root, "--skip-system-test"]
     assert_file "Gemfile" do |content|
-      assert_no_match(/redis/, content)
+      assert_no_match(/capybara/, content)
+      assert_no_match(/selenium-webdriver/, content)
+      assert_no_match(/chromedriver-helper/, content)
     end
+
+    assert_directory("test")
+
+    assert_no_directory("test/system")
   end
 
-  def test_action_cable_redis_gems
-    run_generator
-    assert_file "Gemfile", /^# gem 'redis'/
+  def test_does_not_generate_system_test_files_if_skip_system_test_is_given
+    run_generator [destination_root, "--skip-system-test"]
+
+    Dir.chdir(destination_root) do
+      quietly { `./bin/rails g scaffold User` }
+
+      assert_no_file("test/application_system_test_case.rb")
+      assert_no_file("test/system/users_test.rb")
+    end
   end
 
   def test_inclusion_of_javascript_runtime
     run_generator
     if defined?(JRUBY_VERSION)
       assert_gem "therubyrhino"
+    elsif RUBY_PLATFORM =~ /mingw|mswin/
+      assert_gem "duktape"
     else
-      assert_file "Gemfile", /# gem 'therubyracer', platforms: :ruby/
+      assert_file "Gemfile", /# gem 'mini_racer', platforms: :ruby/
     end
   end
 
-  def test_jquery_is_the_default_javascript_library
+  def test_rails_ujs_is_the_default_ujs_library
     run_generator
     assert_file "app/assets/javascripts/application.js" do |contents|
-      assert_match %r{^//= require jquery}, contents
-      assert_match %r{^//= require jquery_ujs}, contents
-    end
-    assert_gem "jquery-rails"
-  end
-
-  def test_other_javascript_libraries
-    run_generator [destination_root, '-j', 'prototype']
-    assert_file "app/assets/javascripts/application.js" do |contents|
-      assert_match %r{^//= require prototype}, contents
-      assert_match %r{^//= require prototype_ujs}, contents
+      assert_match %r{^//= require rails-ujs}, contents
     end
-    assert_gem "prototype-rails"
   end
 
   def test_javascript_is_skipped_if_required
     run_generator [destination_root, "--skip-javascript"]
 
     assert_no_file "app/assets/javascripts"
-    assert_no_file "vendor/assets/javascripts"
 
     assert_file "app/views/layouts/application.html.erb" do |contents|
       assert_match(/stylesheet_link_tag\s+'application', media: 'all' %>/, contents)
@@ -469,13 +560,26 @@ class AppGeneratorTest < Rails::Generators::TestCase
 
     assert_file "Gemfile" do |content|
       assert_no_match(/coffee-rails/, content)
-      assert_no_match(/jquery-rails/, content)
+      assert_no_match(/uglifier/, content)
+    end
+
+    assert_file "config/environments/production.rb" do |content|
+      assert_no_match(/config\.assets\.js_compressor = :uglifier/, content)
+    end
+  end
+
+  def test_coffeescript_is_skipped_if_required
+    run_generator [destination_root, "--skip-coffee"]
+
+    assert_file "Gemfile" do |content|
+      assert_no_match(/coffee-rails/, content)
+      assert_match(/uglifier/, content)
     end
   end
 
   def test_inclusion_of_jbuilder
     run_generator
-    assert_gem 'jbuilder'
+    assert_gem "jbuilder"
   end
 
   def test_inclusion_of_a_debugger
@@ -485,13 +589,13 @@ class AppGeneratorTest < Rails::Generators::TestCase
         assert_no_match(/byebug/, content)
       end
     else
-      assert_gem 'byebug'
+      assert_gem "byebug"
     end
   end
 
   def test_inclusion_of_listen_related_configuration_by_default
     run_generator
-    if RbConfig::CONFIG['host_os'] =~ /darwin|linux/
+    if RbConfig::CONFIG["host_os"] =~ /darwin|linux/
       assert_listen_related_configuration
     else
       assert_no_listen_related_configuration
@@ -499,17 +603,17 @@ class AppGeneratorTest < Rails::Generators::TestCase
   end
 
   def test_non_inclusion_of_listen_related_configuration_if_skip_listen
-    run_generator [destination_root, '--skip-listen']
+    run_generator [destination_root, "--skip-listen"]
     assert_no_listen_related_configuration
   end
 
   def test_evented_file_update_checker_config
     run_generator
-    assert_file 'config/environments/development.rb' do |content|
-      if RbConfig::CONFIG['host_os'] =~ /darwin|linux/
-        assert_match(/^\s*config.file_watcher = ActiveSupport::EventedFileUpdateChecker/, content)
+    assert_file "config/environments/development.rb" do |content|
+      if RbConfig::CONFIG["host_os"] =~ /darwin|linux/
+        assert_match(/^\s*config\.file_watcher = ActiveSupport::EventedFileUpdateChecker/, content)
       else
-        assert_match(/^\s*# config.file_watcher = ActiveSupport::EventedFileUpdateChecker/, content)
+        assert_match(/^\s*# config\.file_watcher = ActiveSupport::EventedFileUpdateChecker/, content)
       end
     end
   end
@@ -536,47 +640,33 @@ class AppGeneratorTest < Rails::Generators::TestCase
   end
 
   def test_file_is_added_for_backwards_compatibility
-    action :file, 'lib/test_file.rb', 'heres test data'
-    assert_file 'lib/test_file.rb', 'heres test data'
-  end
-
-  def test_tests_are_removed_from_frameworks_if_skip_test_is_given
-    run_generator [destination_root, "--skip-test"]
-    assert_file "config/application.rb", /#\s+require\s+["']rails\/test_unit\/railtie["']/
-  end
-
-  def test_no_active_record_or_tests_if_skips_given
-    run_generator [destination_root, "--skip-test", "--skip-active-record"]
-    assert_file "config/application.rb", /#\s+require\s+["']rails\/test_unit\/railtie["']/
-    assert_file "config/application.rb", /#\s+require\s+["']active_record\/railtie["']/
-    assert_file "config/application.rb", /\s+require\s+["']active_job\/railtie["']/
-  end
-
-  def test_new_hash_style
-    run_generator
-    assert_file "config/initializers/session_store.rb" do |file|
-      assert_match(/config.session_store :cookie_store, key: '_.+_session'/, file)
-    end
+    action :file, "lib/test_file.rb", "heres test data"
+    assert_file "lib/test_file.rb", "heres test data"
   end
 
   def test_pretend_option
     output = run_generator [File.join(destination_root, "myapp"), "--pretend"]
     assert_no_match(/run  bundle install/, output)
+    assert_no_match(/run  git init/, output)
+  end
+
+  def test_quiet_option
+    output = run_generator [File.join(destination_root, "myapp"), "--quiet"]
+    assert_empty output
   end
 
   def test_application_name_with_spaces
     path = File.join(destination_root, "foo bar")
 
     # This also applies to MySQL apps but not with SQLite
-    run_generator [path, "-d", 'postgresql']
+    run_generator [path, "-d", "postgresql"]
 
     assert_file "foo bar/config/database.yml", /database: foo_bar_development/
-    assert_file "foo bar/config/initializers/session_store.rb", /key: '_foo_bar/
   end
 
   def test_web_console
     run_generator
-    assert_gem 'web-console'
+    assert_gem "web-console"
   end
 
   def test_web_console_with_dev_option
@@ -584,7 +674,7 @@ class AppGeneratorTest < Rails::Generators::TestCase
 
     assert_file "Gemfile" do |content|
       assert_match(/gem 'web-console',\s+github: 'rails\/web-console'/, content)
-      assert_no_match(/\Agem 'web-console'\z/, content)
+      assert_no_match(/\Agem 'web-console', '>= 3\.3\.0'\z/, content)
     end
   end
 
@@ -593,13 +683,28 @@ class AppGeneratorTest < Rails::Generators::TestCase
 
     assert_file "Gemfile" do |content|
       assert_match(/gem 'web-console',\s+github: 'rails\/web-console'/, content)
-      assert_no_match(/\Agem 'web-console'\z/, content)
+      assert_no_match(/\Agem 'web-console', '>= 3\.3\.0'\z/, content)
     end
   end
 
+  def test_generation_runs_bundle_install
+    assert_generates_with_bundler
+  end
+
+  def test_dev_option
+    assert_generates_with_bundler dev: true
+    rails_path = File.expand_path("../../..", Rails.root)
+    assert_file "Gemfile", /^gem\s+["']rails["'],\s+path:\s+["']#{Regexp.escape(rails_path)}["']$/
+  end
+
+  def test_edge_option
+    assert_generates_with_bundler edge: true
+    assert_file "Gemfile", %r{^gem\s+["']rails["'],\s+github:\s+["']#{Regexp.escape("rails/rails")}["']$}
+  end
+
   def test_spring
     run_generator
-    assert_gem 'spring'
+    assert_gem "spring"
   end
 
   def test_spring_binstubs
@@ -608,9 +713,9 @@ class AppGeneratorTest < Rails::Generators::TestCase
       @binstub_called ||= 0
 
       case command
-      when 'install'
+      when "install"
         # Called when running bundle, we just want to stub it so nothing to do here.
-      when 'exec spring binstub --all'
+      when "exec spring binstub --all"
         @binstub_called += 1
         assert_equal 1, @binstub_called, "exec spring binstub --all expected to be called once, but was called #{@install_called} times."
       end
@@ -635,7 +740,7 @@ class AppGeneratorTest < Rails::Generators::TestCase
   def test_skip_spring
     run_generator [destination_root, "--skip-spring"]
 
-    assert_no_file 'config/spring.rb'
+    assert_no_file "config/spring.rb"
     assert_file "Gemfile" do |content|
       assert_no_match(/spring/, content)
     end
@@ -649,6 +754,45 @@ class AppGeneratorTest < Rails::Generators::TestCase
     end
   end
 
+  def test_webpack_option
+    command_check = -> command, *_ do
+      @called ||= 0
+      if command == "webpacker:install"
+        @called += 1
+        assert_equal 1, @called, "webpacker:install expected to be called once, but was called #{@called} times."
+      end
+    end
+
+    generator([destination_root], webpack: "webpack").stub(:rails_command, command_check) do
+      generator.stub :bundle_command, nil do
+        quietly { generator.invoke_all }
+      end
+    end
+
+    assert_gem "webpacker"
+  end
+
+  def test_webpack_option_with_js_framework
+    command_check = -> command, *_ do
+      case command
+      when "webpacker:install"
+        @webpacker ||= 0
+        @webpacker += 1
+        assert_equal 1, @webpacker, "webpacker:install expected to be called once, but was called #{@webpacker} times."
+      when "webpacker:install:react"
+        @react ||= 0
+        @react += 1
+        assert_equal 1, @react, "webpacker:install:react expected to be called once, but was called #{@react} times."
+      end
+    end
+
+    generator([destination_root], webpack: "react").stub(:rails_command, command_check) do
+      generator.stub :bundle_command, nil do
+        quietly { generator.invoke_all }
+      end
+    end
+  end
+
   def test_generator_if_skip_turbolinks_is_given
     run_generator [destination_root, "--skip-turbolinks"]
 
@@ -663,28 +807,51 @@ class AppGeneratorTest < Rails::Generators::TestCase
     end
   end
 
-  def test_gitignore_when_sqlite3
+  def test_bootsnap
     run_generator
 
-    assert_file '.gitignore' do |content|
-      assert_match(/sqlite3/, content)
+    assert_gem "bootsnap"
+    assert_file "config/boot.rb" do |content|
+      assert_match(/require 'bootsnap\/setup'/, content)
+    end
+  end
+
+  def test_skip_bootsnap
+    run_generator [destination_root, "--skip-bootsnap"]
+
+    assert_file "Gemfile" do |content|
+      assert_no_match(/bootsnap/, content)
+    end
+    assert_file "config/boot.rb" do |content|
+      assert_no_match(/require 'bootsnap\/setup'/, content)
     end
   end
 
-  def test_gitignore_when_no_active_record
-    run_generator [destination_root, '--skip-active-record']
+  def test_bootsnap_with_dev_option
+    run_generator [destination_root, "--dev"]
 
-    assert_file '.gitignore' do |content|
-      assert_no_match(/sqlite/i, content)
+    assert_file "Gemfile" do |content|
+      assert_no_match(/bootsnap/, content)
+    end
+    assert_file "config/boot.rb" do |content|
+      assert_no_match(/require 'bootsnap\/setup'/, content)
     end
   end
 
-  def test_gitignore_when_non_sqlite3_db
-    run_generator([destination_root, "-d", "mysql"])
+  def test_inclusion_of_ruby_version
+    run_generator
 
-    assert_file '.gitignore' do |content|
-      assert_no_match(/sqlite/i, content)
+    assert_file "Gemfile" do |content|
+      assert_match(/ruby '#{RUBY_VERSION}'/, content)
     end
+    assert_file ".ruby-version" do |content|
+      assert_match(/#{RUBY_VERSION}/, content)
+    end
+  end
+
+  def test_version_control_initializes_git_repo
+    run_generator [destination_root]
+    assert_directory ".git"
   end
 
   def test_create_keeps
@@ -704,7 +871,6 @@ class AppGeneratorTest < Rails::Generators::TestCase
       test/helpers
       test/integration
       tmp
-      vendor/assets/stylesheets
     )
     folders_with_keep.each do |folder|
       assert_file("#{folder}/.keep")
@@ -713,7 +879,7 @@ class AppGeneratorTest < Rails::Generators::TestCase
 
   def test_psych_gem
     run_generator
-    gem_regex = /gem 'psych',\s+'~> 2.0',\s+platforms: :rbx/
+    gem_regex = /gem 'psych',\s+'~> 2\.0',\s+platforms: :rbx/
 
     assert_file "Gemfile" do |content|
       if defined?(Rubinius)
@@ -725,18 +891,18 @@ class AppGeneratorTest < Rails::Generators::TestCase
   end
 
   def test_after_bundle_callback
-    path = 'http://example.org/rails_template'
-    template = %{ after_bundle { run 'echo ran after_bundle' } }
+    path = "http://example.org/rails_template"
+    template = %{ after_bundle { run 'echo ran after_bundle' } }.dup
     template.instance_eval "def read; self; end" # Make the string respond to read
 
     check_open = -> *args do
-      assert_equal [ path, 'Accept' => 'application/x-thor-template' ], args
+      assert_equal [ path, "Accept" => "application/x-thor-template" ], args
       template
     end
 
-    sequence = ['install', 'exec spring binstub --all', 'echo ran after_bundle']
-      @sequence_step ||= 0
-    ensure_bundler_first = -> command do
+    sequence = ["git init", "install", "exec spring binstub --all", "active_storage:install", "echo ran after_bundle"]
+    @sequence_step ||= 0
+    ensure_bundler_first = -> command, options = nil do
       assert_equal sequence[@sequence_step], command, "commands should be called in sequence #{sequence}"
       @sequence_step += 1
     end
@@ -744,51 +910,87 @@ class AppGeneratorTest < Rails::Generators::TestCase
     generator([destination_root], template: path).stub(:open, check_open, template) do
       generator.stub(:bundle_command, ensure_bundler_first) do
         generator.stub(:run, ensure_bundler_first) do
-          quietly { generator.invoke_all }
+          generator.stub(:rails_command, ensure_bundler_first) do
+            quietly { generator.invoke_all }
+          end
         end
       end
     end
 
-    assert_equal 3, @sequence_step
+    assert_equal 5, @sequence_step
   end
 
-  protected
+  def test_gitignore
+    run_generator
 
-  def stub_rails_application(root)
-    Rails.application.config.root = root
-    Rails.application.class.stub(:name, "Myapp") do
-      yield
+    assert_file ".gitignore" do |content|
+      assert_match(/config\/master\.key/, content)
     end
   end
 
-  def action(*args, &block)
-    capture(:stdout) { generator.send(*args, &block) }
+  def test_system_tests_directory_generated
+    run_generator
+
+    assert_file("test/system/.keep")
+    assert_directory("test/system")
   end
 
-  def assert_gem(gem, constraint = nil)
-    if constraint
-      assert_file "Gemfile", /^\s*gem\s+["']#{gem}["'], #{constraint}$*/
-    else
-      assert_file "Gemfile", /^\s*gem\s+["']#{gem}["']$*/
+  private
+    def stub_rails_application(root)
+      Rails.application.config.root = root
+      Rails.application.class.stub(:name, "Myapp") do
+        yield
+      end
     end
-  end
 
-  def assert_listen_related_configuration
-    assert_gem 'listen'
-    assert_gem 'spring-watcher-listen'
+    def action(*args, &block)
+      capture(:stdout) { generator.send(*args, &block) }
+    end
 
-    assert_file 'config/environments/development.rb' do |content|
-      assert_match(/^\s*config.file_watcher = ActiveSupport::EventedFileUpdateChecker/, content)
+    def assert_gem(gem, constraint = nil)
+      if constraint
+        assert_file "Gemfile", /^\s*gem\s+["']#{gem}["'], #{constraint}$*/
+      else
+        assert_file "Gemfile", /^\s*gem\s+["']#{gem}["']$*/
+      end
+    end
+
+    def assert_listen_related_configuration
+      assert_gem "listen"
+      assert_gem "spring-watcher-listen"
+
+      assert_file "config/environments/development.rb" do |content|
+        assert_match(/^\s*config\.file_watcher = ActiveSupport::EventedFileUpdateChecker/, content)
+      end
     end
-  end
 
-  def assert_no_listen_related_configuration
-    assert_file 'Gemfile' do |content|
-      assert_no_match(/listen/, content)
+    def assert_no_listen_related_configuration
+      assert_file "Gemfile" do |content|
+        assert_no_match(/listen/, content)
+      end
+
+      assert_file "config/environments/development.rb" do |content|
+        assert_match(/^\s*# config\.file_watcher = ActiveSupport::EventedFileUpdateChecker/, content)
+      end
     end
 
-    assert_file 'config/environments/development.rb' do |content|
-      assert_match(/^\s*# config.file_watcher = ActiveSupport::EventedFileUpdateChecker/, content)
+    def assert_generates_with_bundler(options = {})
+      generator([destination_root], options)
+
+      command_check = -> command do
+        @install_called ||= 0
+
+        case command
+        when "install"
+          @install_called += 1
+          assert_equal 1, @install_called, "install expected to be called once, but was called #{@install_called} times"
+        when "exec spring binstub --all"
+          # Called when running tests with spring, let through unscathed.
+        end
+      end
+
+      generator.stub :bundle_command, command_check do
+        quietly { generator.invoke_all }
+      end
     end
-  end
 end
diff --git a/railties/test/generators/application_record_generator_test.rb b/railties/test/generators/application_record_generator_test.rb
new file mode 100644
index 0000000000..2c0aa7211b
--- /dev/null
+++ b/railties/test/generators/application_record_generator_test.rb
@@ -0,0 +1,16 @@
+# frozen_string_literal: true
+
+require "generators/generators_test_helper"
+require "rails/generators/rails/application_record/application_record_generator"
+
+class ApplicationRecordGeneratorTest < Rails::Generators::TestCase
+  include GeneratorsTestHelper
+
+  def test_application_record_skeleton_is_created
+    run_generator
+    assert_file "app/models/application_record.rb" do |record|
+      assert_match(/class ApplicationRecord < ActiveRecord::Base/, record)
+      assert_match(/self\.abstract_class = true/, record)
+    end
+  end
+end
diff --git a/railties/test/generators/argv_scrubber_test.rb b/railties/test/generators/argv_scrubber_test.rb
index 31e07bc8da..9ef61dc978 100644
--- a/railties/test/generators/argv_scrubber_test.rb
+++ b/railties/test/generators/argv_scrubber_test.rb
@@ -1,7 +1,9 @@
-require 'active_support/test_case'
-require 'active_support/testing/autorun'
-require 'rails/generators/rails/app/app_generator'
-require 'tempfile'
+# frozen_string_literal: true
+
+require "active_support/test_case"
+require "active_support/testing/autorun"
+require "rails/generators/rails/app/app_generator"
+require "tempfile"
 
 module Rails
   module Generators
@@ -11,7 +13,7 @@ module Rails
       # *must* act this way, I just want to prevent regressions.
 
       def test_version
-        ['-v', '--version'].each do |str|
+        ["-v", "--version"].each do |str|
           scrubber = ARGVScrubber.new [str]
           output    = nil
           exit_code = nil
@@ -26,37 +28,37 @@ module Rails
       end
 
       def test_default_help
-        argv = ['zomg', 'how', 'are', 'you']
+        argv = ["zomg", "how", "are", "you"]
         scrubber = ARGVScrubber.new argv
         args = scrubber.prepare!
-        assert_equal ['--help'] + argv.drop(1), args
+        assert_equal ["--help"] + argv.drop(1), args
       end
 
       def test_prepare_returns_args
-        scrubber = ARGVScrubber.new ['hi mom']
+        scrubber = ARGVScrubber.new ["hi mom"]
         args = scrubber.prepare!
-        assert_equal '--help', args.first
+        assert_equal "--help", args.first
       end
 
       def test_no_mutations
-        scrubber = ARGVScrubber.new ['hi mom'].freeze
+        scrubber = ARGVScrubber.new ["hi mom"].freeze
         args = scrubber.prepare!
-        assert_equal '--help', args.first
+        assert_equal "--help", args.first
       end
 
       def test_new_command_no_rc
         scrubber = Class.new(ARGVScrubber) {
           def self.default_rc_file
-            File.join(Dir.tmpdir, 'whatever')
+            File.join(Dir.tmpdir, "whatever")
           end
-        }.new ['new']
+        }.new ["new"]
         args = scrubber.prepare!
         assert_equal [], args
       end
 
       def test_new_homedir_rc
-        file = Tempfile.new 'myrcfile'
-        file.puts '--hello-world'
+        file = Tempfile.new "myrcfile"
+        file.puts "--hello-world"
         file.flush
 
         message = nil
@@ -65,10 +67,10 @@ module Rails
             file.path
           end
           define_method(:puts) { |msg| message = msg }
-        }.new ['new']
+        }.new ["new"]
         args = scrubber.prepare!
-        assert_equal ['--hello-world'], args
-        assert_match 'hello-world', message
+        assert_equal ["--hello-world"], args
+        assert_match "hello-world", message
         assert_match file.path, message
       ensure
         file.close
@@ -76,33 +78,32 @@ module Rails
       end
 
       def test_rc_whitespace_separated
-        file = Tempfile.new 'myrcfile'
-        file.puts '--hello --world'
+        file = Tempfile.new "myrcfile"
+        file.puts "--hello --world"
         file.flush
 
-        message = nil
         scrubber = Class.new(ARGVScrubber) {
-          define_method(:puts) { |msg| message = msg }
-        }.new ['new', "--rc=#{file.path}"]
+          define_method(:puts) { |msg| }
+        }.new ["new", "--rc=#{file.path}"]
         args = scrubber.prepare!
-        assert_equal ['--hello', '--world'], args
+        assert_equal ["--hello", "--world"], args
       ensure
         file.close
         file.unlink
       end
 
       def test_new_rc_option
-        file = Tempfile.new 'myrcfile'
-        file.puts '--hello-world'
+        file = Tempfile.new "myrcfile"
+        file.puts "--hello-world"
         file.flush
 
         message = nil
         scrubber = Class.new(ARGVScrubber) {
           define_method(:puts) { |msg| message = msg }
-        }.new ['new', "--rc=#{file.path}"]
+        }.new ["new", "--rc=#{file.path}"]
         args = scrubber.prepare!
-        assert_equal ['--hello-world'], args
-        assert_match 'hello-world', message
+        assert_equal ["--hello-world"], args
+        assert_match "hello-world", message
         assert_match file.path, message
       ensure
         file.close
@@ -110,14 +111,14 @@ module Rails
       end
 
       def test_new_rc_option_and_custom_options
-        file = Tempfile.new 'myrcfile'
-        file.puts '--hello'
-        file.puts '--world'
+        file = Tempfile.new "myrcfile"
+        file.puts "--hello"
+        file.puts "--world"
         file.flush
 
         scrubber = Class.new(ARGVScrubber) {
           define_method(:puts) { |msg| }
-        }.new ['new', 'tenderapp', '--love', "--rc=#{file.path}"]
+        }.new ["new", "tenderapp", "--love", "--rc=#{file.path}"]
 
         args = scrubber.prepare!
         assert_equal ["tenderapp", "--hello", "--world", "--love"], args
@@ -127,7 +128,7 @@ module Rails
       end
 
       def test_no_rc
-        scrubber = ARGVScrubber.new ['new', '--no-rc']
+        scrubber = ARGVScrubber.new ["new", "--no-rc"]
         args = scrubber.prepare!
         assert_equal [], args
       end
diff --git a/railties/test/generators/assets_generator_test.rb b/railties/test/generators/assets_generator_test.rb
index a2b94f2e50..3cec41dbf8 100644
--- a/railties/test/generators/assets_generator_test.rb
+++ b/railties/test/generators/assets_generator_test.rb
@@ -1,5 +1,7 @@
-require 'generators/generators_test_helper'
-require 'rails/generators/rails/assets/assets_generator'
+# frozen_string_literal: true
+
+require "generators/generators_test_helper"
+require "rails/generators/rails/assets/assets_generator"
 
 class AssetsGeneratorTest < Rails::Generators::TestCase
   include GeneratorsTestHelper
diff --git a/railties/test/generators/channel_generator_test.rb b/railties/test/generators/channel_generator_test.rb
index e3edde681f..e238197eba 100644
--- a/railties/test/generators/channel_generator_test.rb
+++ b/railties/test/generators/channel_generator_test.rb
@@ -1,12 +1,14 @@
-require 'generators/generators_test_helper'
-require 'rails/generators/channel/channel_generator'
+# frozen_string_literal: true
+
+require "generators/generators_test_helper"
+require "rails/generators/channel/channel_generator"
 
 class ChannelGeneratorTest < Rails::Generators::TestCase
   include GeneratorsTestHelper
   tests Rails::Generators::ChannelGenerator
 
   def test_application_cable_skeleton_is_created
-    run_generator ['books']
+    run_generator ["books"]
 
     assert_file "app/channels/application_cable/channel.rb" do |cable|
       assert_match(/module ApplicationCable\n  class Channel < ActionCable::Channel::Base\n/, cable)
@@ -18,19 +20,19 @@ class ChannelGeneratorTest < Rails::Generators::TestCase
   end
 
   def test_channel_is_created
-    run_generator ['chat']
+    run_generator ["chat"]
 
     assert_file "app/channels/chat_channel.rb" do |channel|
       assert_match(/class ChatChannel < ApplicationCable::Channel/, channel)
     end
 
     assert_file "app/assets/javascripts/channels/chat.js" do |channel|
-      assert_match(/App.chat = App.cable.subscriptions.create\("ChatChannel/, channel)
+      assert_match(/App\.chat = App\.cable\.subscriptions\.create\("ChatChannel/, channel)
     end
   end
 
   def test_channel_with_multiple_actions_is_created
-    run_generator ['chat', 'speak', 'mute']
+    run_generator ["chat", "speak", "mute"]
 
     assert_file "app/channels/chat_channel.rb" do |channel|
       assert_match(/class ChatChannel < ApplicationCable::Channel/, channel)
@@ -39,14 +41,14 @@ class ChannelGeneratorTest < Rails::Generators::TestCase
     end
 
     assert_file "app/assets/javascripts/channels/chat.js" do |channel|
-      assert_match(/App.chat = App.cable.subscriptions.create\("ChatChannel/, channel)
+      assert_match(/App\.chat = App\.cable\.subscriptions\.create\("ChatChannel/, channel)
       assert_match(/,\n\n  speak/, channel)
       assert_match(/,\n\n  mute: function\(\) \{\n    return this\.perform\('mute'\);\n  \}\n\}\);/, channel)
     end
   end
 
   def test_channel_asset_is_not_created_when_skip_assets_is_passed
-    run_generator ['chat', '--skip-assets']
+    run_generator ["chat", "--skip-assets"]
 
     assert_file "app/channels/chat_channel.rb" do |channel|
       assert_match(/class ChatChannel < ApplicationCable::Channel/, channel)
@@ -56,16 +58,16 @@ class ChannelGeneratorTest < Rails::Generators::TestCase
   end
 
   def test_cable_js_is_created_if_not_present_already
-    run_generator ['chat']
+    run_generator ["chat"]
     FileUtils.rm("#{destination_root}/app/assets/javascripts/cable.js")
-    run_generator ['camp']
+    run_generator ["camp"]
 
     assert_file "app/assets/javascripts/cable.js"
   end
 
   def test_channel_on_revoke
-    run_generator ['chat']
-    run_generator ['chat'], behavior: :revoke
+    run_generator ["chat"]
+    run_generator ["chat"], behavior: :revoke
 
     assert_no_file "app/channels/chat_channel.rb"
     assert_no_file "app/assets/javascripts/channels/chat.js"
diff --git a/railties/test/generators/controller_generator_test.rb b/railties/test/generators/controller_generator_test.rb
index 1351151afb..a3218951a6 100644
--- a/railties/test/generators/controller_generator_test.rb
+++ b/railties/test/generators/controller_generator_test.rb
@@ -1,5 +1,7 @@
-require 'generators/generators_test_helper'
-require 'rails/generators/rails/controller/controller_generator'
+# frozen_string_literal: true
+
+require "generators/generators_test_helper"
+require "rails/generators/rails/controller/controller_generator"
 
 class ControllerGeneratorTest < Rails::Generators::TestCase
   include GeneratorsTestHelper
@@ -19,7 +21,7 @@ class ControllerGeneratorTest < Rails::Generators::TestCase
 
   def test_check_class_collision
     Object.send :const_set, :ObjectController, Class.new
-    content = capture(:stderr){ run_generator ["object"] }
+    content = capture(:stderr) { run_generator ["object"] }
     assert_match(/The name 'ObjectController' is either already used in your application or reserved/, content)
   ensure
     Object.send :remove_const, :ObjectController
@@ -65,7 +67,7 @@ class ControllerGeneratorTest < Rails::Generators::TestCase
 
   def test_add_routes
     run_generator
-    assert_file "config/routes.rb", /get 'account\/foo'/, /get 'account\/bar'/
+    assert_file "config/routes.rb", /^  get 'account\/foo'/, /^  get 'account\/bar'/
   end
 
   def test_skip_routes
@@ -100,4 +102,11 @@ class ControllerGeneratorTest < Rails::Generators::TestCase
       assert_match(/^  namespace :admin do\n    get 'dashboard\/index'\n  end$/, route)
     end
   end
+
+  def test_namespaced_routes_with_multiple_actions_are_created_in_routes
+    run_generator ["admin/dashboard", "index", "show"]
+    assert_file "config/routes.rb" do |route|
+      assert_match(/^  namespace :admin do\n    get 'dashboard\/index'\n    get 'dashboard\/show'\n  end$/, route)
+    end
+  end
 end
diff --git a/railties/test/generators/create_migration_test.rb b/railties/test/generators/create_migration_test.rb
index e16a77479a..3cb7fd6baa 100644
--- a/railties/test/generators/create_migration_test.rb
+++ b/railties/test/generators/create_migration_test.rb
@@ -1,5 +1,7 @@
-require 'generators/generators_test_helper'
-require 'rails/generators/rails/migration/migration_generator'
+# frozen_string_literal: true
+
+require "generators/generators_test_helper"
+require "rails/generators/rails/migration/migration_generator"
 
 class CreateMigrationTest < Rails::Generators::TestCase
   include GeneratorsTestHelper
@@ -19,12 +21,12 @@ class CreateMigrationTest < Rails::Generators::TestCase
   end
 
   def create_migration(destination_path = default_destination_path, config = {}, generator_options = {}, &block)
-    migration_name = File.basename(destination_path, '.rb')
+    migration_name = File.basename(destination_path, ".rb")
     generator([migration_name], generator_options)
     generator.set_migration_assigns!(destination_path)
 
     dir, base = File.split(destination_path)
-    timestamped_destination_path = File.join(dir, ["%migration_number%", base].join('_'))
+    timestamped_destination_path = File.join(dir, ["%migration_number%", base].join("_"))
 
     @migration = Rails::Generators::Actions::CreateMigration.new(generator, timestamped_destination_path, block || "contents", config)
   end
@@ -46,7 +48,7 @@ class CreateMigrationTest < Rails::Generators::TestCase
   def test_invoke
     create_migration
 
-    assert_match(/create  db\/migrate\/1_create_articles.rb\n/, invoke!)
+    assert_match(/create  db\/migrate\/1_create_articles\.rb\n/, invoke!)
     assert_file @migration.destination
   end
 
@@ -67,7 +69,7 @@ class CreateMigrationTest < Rails::Generators::TestCase
     migration_exists!
     create_migration
 
-    assert_match(/identical  db\/migrate\/1_create_articles.rb\n/, invoke!)
+    assert_match(/identical  db\/migrate\/1_create_articles\.rb\n/, invoke!)
     assert @migration.identical?
   end
 
@@ -84,8 +86,8 @@ class CreateMigrationTest < Rails::Generators::TestCase
     create_migration(dest, force: true) { "different content" }
 
     stdout = invoke!
-    assert_match(/remove  db\/migrate\/1_migration.rb\n/, stdout)
-    assert_match(/create  db\/migrate\/2_migration.rb\n/, stdout)
+    assert_match(/remove  db\/migrate\/1_migration\.rb\n/, stdout)
+    assert_match(/create  db\/migrate\/2_migration\.rb\n/, stdout)
     assert_file @migration.destination
     assert_no_file @existing_migration.destination
   end
@@ -97,8 +99,8 @@ class CreateMigrationTest < Rails::Generators::TestCase
     end
 
     stdout = invoke!
-    assert_match(/remove  db\/migrate\/1_create_articles.rb\n/, stdout)
-    assert_match(/create  db\/migrate\/2_create_articles.rb\n/, stdout)
+    assert_match(/remove  db\/migrate\/1_create_articles\.rb\n/, stdout)
+    assert_match(/create  db\/migrate\/2_create_articles\.rb\n/, stdout)
     assert_no_file @migration.destination
   end
 
@@ -106,7 +108,7 @@ class CreateMigrationTest < Rails::Generators::TestCase
     migration_exists!
     create_migration(default_destination_path, {}, { skip: true }) { "different content" }
 
-    assert_match(/skip  db\/migrate\/2_create_articles.rb\n/, invoke!)
+    assert_match(/skip  db\/migrate\/2_create_articles\.rb\n/, invoke!)
     assert_no_file @migration.destination
   end
 
@@ -114,7 +116,7 @@ class CreateMigrationTest < Rails::Generators::TestCase
     migration_exists!
     create_migration
 
-    assert_match(/remove  db\/migrate\/1_create_articles.rb\n/, revoke!)
+    assert_match(/remove  db\/migrate\/1_create_articles\.rb\n/, revoke!)
     assert_no_file @existing_migration.destination
   end
 
@@ -122,13 +124,13 @@ class CreateMigrationTest < Rails::Generators::TestCase
     migration_exists!
     create_migration(default_destination_path, {}, { pretend: true })
 
-    assert_match(/remove  db\/migrate\/1_create_articles.rb\n/, revoke!)
+    assert_match(/remove  db\/migrate\/1_create_articles\.rb\n/, revoke!)
     assert_file @existing_migration.destination
   end
 
   def test_revoke_when_no_exists
     create_migration
 
-    assert_match(/remove  db\/migrate\/1_create_articles.rb\n/, revoke!)
+    assert_match(/remove  db\/migrate\/1_create_articles\.rb\n/, revoke!)
   end
 end
diff --git a/railties/test/generators/generated_attribute_test.rb b/railties/test/generators/generated_attribute_test.rb
index ee7c009305..c6f7bdeda1 100644
--- a/railties/test/generators/generated_attribute_test.rb
+++ b/railties/test/generators/generated_attribute_test.rb
@@ -1,5 +1,7 @@
-require 'generators/generators_test_helper'
-require 'rails/generators/generated_attribute'
+# frozen_string_literal: true
+
+require "generators/generators_test_helper"
+require "rails/generators/generated_attribute"
 
 class GeneratedAttributeTest < Rails::Generators::TestCase
   include GeneratorsTestHelper
@@ -51,7 +53,7 @@ class GeneratedAttributeTest < Rails::Generators::TestCase
   end
 
   def test_default_value_is_decimal
-    assert_field_default_value :decimal, '9.99'
+    assert_field_default_value :decimal, "9.99"
   end
 
   def test_default_value_is_datetime
@@ -65,7 +67,7 @@ class GeneratedAttributeTest < Rails::Generators::TestCase
   end
 
   def test_default_value_is_string
-    assert_field_default_value :string, 'MyString'
+    assert_field_default_value :string, "MyString"
   end
 
   def test_default_value_for_type
@@ -74,7 +76,7 @@ class GeneratedAttributeTest < Rails::Generators::TestCase
   end
 
   def test_default_value_is_text
-    assert_field_default_value :text, 'MyText'
+    assert_field_default_value :text, "MyText"
   end
 
   def test_default_value_is_boolean
@@ -89,14 +91,14 @@ class GeneratedAttributeTest < Rails::Generators::TestCase
 
   def test_default_value_is_empty_string
     %w(foo bar baz).each do |attribute_type|
-      assert_field_default_value attribute_type, ''
+      assert_field_default_value attribute_type, ""
     end
   end
 
   def test_human_name
     assert_equal(
-      'Full name',
-      create_generated_attribute(:string, 'full_name').human_name
+      "Full name",
+      create_generated_attribute(:string, "full_name").human_name
     )
   end
 
@@ -125,21 +127,21 @@ class GeneratedAttributeTest < Rails::Generators::TestCase
   end
 
   def test_blank_type_defaults_to_string_raises_exception
-    assert_equal :string, create_generated_attribute(nil, 'title').type
-    assert_equal :string, create_generated_attribute("", 'title').type
+    assert_equal :string, create_generated_attribute(nil, "title").type
+    assert_equal :string, create_generated_attribute("", "title").type
   end
 
   def test_handles_index_names_for_references
-    assert_equal "post", create_generated_attribute('string', 'post').index_name
-    assert_equal "post_id", create_generated_attribute('references', 'post').index_name
-    assert_equal "post_id", create_generated_attribute('belongs_to', 'post').index_name
-    assert_equal ["post_id", "post_type"], create_generated_attribute('references{polymorphic}', 'post').index_name
+    assert_equal "post", create_generated_attribute("string", "post").index_name
+    assert_equal "post_id", create_generated_attribute("references", "post").index_name
+    assert_equal "post_id", create_generated_attribute("belongs_to", "post").index_name
+    assert_equal ["post_id", "post_type"], create_generated_attribute("references{polymorphic}", "post").index_name
   end
 
   def test_handles_column_names_for_references
-    assert_equal "post", create_generated_attribute('string', 'post').column_name
-    assert_equal "post_id", create_generated_attribute('references', 'post').column_name
-    assert_equal "post_id", create_generated_attribute('belongs_to', 'post').column_name
+    assert_equal "post", create_generated_attribute("string", "post").column_name
+    assert_equal "post_id", create_generated_attribute("references", "post").column_name
+    assert_equal "post_id", create_generated_attribute("belongs_to", "post").column_name
   end
 
   def test_parse_required_attribute_with_index
diff --git a/railties/test/generators/generator_generator_test.rb b/railties/test/generators/generator_generator_test.rb
index dcfeaaa8e0..eaa964cabc 100644
--- a/railties/test/generators/generator_generator_test.rb
+++ b/railties/test/generators/generator_generator_test.rb
@@ -1,5 +1,7 @@
-require 'generators/generators_test_helper'
-require 'rails/generators/rails/generator/generator_generator'
+# frozen_string_literal: true
+
+require "generators/generators_test_helper"
+require "rails/generators/rails/generator/generator_generator"
 
 class GeneratorGeneratorTest < Rails::Generators::TestCase
   include GeneratorsTestHelper
@@ -12,7 +14,7 @@ class GeneratorGeneratorTest < Rails::Generators::TestCase
       lib/generators/awesome
       lib/generators/awesome/USAGE
       lib/generators/awesome/templates
-    ).each{ |path| assert_file path }
+    ).each { |path| assert_file path }
 
     assert_file "lib/generators/awesome/awesome_generator.rb",
                 /class AwesomeGenerator < Rails::Generators::NamedBase/
@@ -28,7 +30,7 @@ class GeneratorGeneratorTest < Rails::Generators::TestCase
       lib/generators/rails/awesome
       lib/generators/rails/awesome/USAGE
       lib/generators/rails/awesome/templates
-    ).each{ |path| assert_file path }
+    ).each { |path| assert_file path }
 
     assert_file "lib/generators/rails/awesome/awesome_generator.rb",
                 /class Rails::AwesomeGenerator < Rails::Generators::NamedBase/
@@ -44,7 +46,7 @@ class GeneratorGeneratorTest < Rails::Generators::TestCase
       lib/generators/
       lib/generators/USAGE
       lib/generators/templates
-    ).each{ |path| assert_file path }
+    ).each { |path| assert_file path }
 
     assert_file "lib/generators/awesome_generator.rb",
                 /class AwesomeGenerator < Rails::Generators::NamedBase/
@@ -60,7 +62,7 @@ class GeneratorGeneratorTest < Rails::Generators::TestCase
       lib/generators/rails
       lib/generators/rails/USAGE
       lib/generators/rails/templates
-    ).each{ |path| assert_file path }
+    ).each { |path| assert_file path }
 
     assert_file "lib/generators/rails/awesome_generator.rb",
                 /class Rails::AwesomeGenerator < Rails::Generators::NamedBase/
diff --git a/railties/test/generators/generator_test.rb b/railties/test/generators/generator_test.rb
index 8ef44a8dcb..5f7daf5ac3 100644
--- a/railties/test/generators/generator_test.rb
+++ b/railties/test/generators/generator_test.rb
@@ -1,6 +1,8 @@
-require 'active_support/test_case'
-require 'active_support/testing/autorun'
-require 'rails/generators/app_base'
+# frozen_string_literal: true
+
+require "active_support/test_case"
+require "active_support/testing/autorun"
+require "rails/generators/app_base"
 
 module Rails
   module Generators
@@ -20,47 +22,47 @@ module Rails
       end
 
       def test_construction
-        klass     = make_builder_class
-        assert klass.start(['new', 'blah'])
+        klass = make_builder_class
+        assert klass.start(["new", "blah"])
       end
 
       def test_add_gem
         klass = make_builder_class
-        generator = klass.start(['new', 'blah'])
-        generator.gemfile_entry 'tenderlove'
-        assert_includes generator.gemfile_entries.map(&:name), 'tenderlove'
+        generator = klass.start(["new", "blah"])
+        generator.gemfile_entry "tenderlove"
+        assert_includes generator.gemfile_entries.map(&:name), "tenderlove"
       end
 
       def test_add_gem_with_version
         klass = make_builder_class
-        generator = klass.start(['new', 'blah'])
-        generator.gemfile_entry 'tenderlove', '2.0.0'
+        generator = klass.start(["new", "blah"])
+        generator.gemfile_entry "tenderlove", "2.0.0"
         assert generator.gemfile_entries.find { |gfe|
-          gfe.name == 'tenderlove' && gfe.version == '2.0.0'
+          gfe.name == "tenderlove" && gfe.version == "2.0.0"
         }
       end
 
       def test_add_github_gem
         klass = make_builder_class
-        generator = klass.start(['new', 'blah'])
-        generator.gemfile_entry 'tenderlove', github: 'hello world'
+        generator = klass.start(["new", "blah"])
+        generator.gemfile_entry "tenderlove", github: "hello world"
         assert generator.gemfile_entries.find { |gfe|
-          gfe.name == 'tenderlove' && gfe.options[:github] == 'hello world'
+          gfe.name == "tenderlove" && gfe.options[:github] == "hello world"
         }
       end
 
       def test_add_path_gem
         klass = make_builder_class
-        generator = klass.start(['new', 'blah'])
-        generator.gemfile_entry 'tenderlove', path: 'hello world'
+        generator = klass.start(["new", "blah"])
+        generator.gemfile_entry "tenderlove", path: "hello world"
         assert generator.gemfile_entries.find { |gfe|
-          gfe.name == 'tenderlove' && gfe.options[:path] == 'hello world'
+          gfe.name == "tenderlove" && gfe.options[:path] == "hello world"
         }
       end
 
       def test_filter
         klass     = make_builder_class
-        generator = klass.start(['new', 'blah'])
+        generator = klass.start(["new", "blah"])
         gems      = generator.gemfile_entries
         generator.add_gem_entry_filter { |gem|
           gem.name != gems.first.name
@@ -70,7 +72,7 @@ module Rails
 
       def test_two_filters
         klass     = make_builder_class
-        generator = klass.start(['new', 'blah'])
+        generator = klass.start(["new", "blah"])
         gems      = generator.gemfile_entries
         generator.add_gem_entry_filter { |gem|
           gem.name != gems.first.name
@@ -83,17 +85,17 @@ module Rails
 
       def test_recommended_rails_versions
         klass     = make_builder_class
-        generator = klass.start(['new', 'blah'])
+        generator = klass.start(["new", "blah"])
 
         specifier_for = -> v { generator.send(:rails_version_specifier, Gem::Version.new(v)) }
 
-        assert_equal '~> 4.1.13', specifier_for['4.1.13']
-        assert_equal ['>= 4.1.6.rc1', '< 4.2'], specifier_for['4.1.6.rc1']
-        assert_equal ['~> 4.1.7', '>= 4.1.7.1'], specifier_for['4.1.7.1']
-        assert_equal ['~> 4.1.7', '>= 4.1.7.1.2'], specifier_for['4.1.7.1.2']
-        assert_equal ['>= 4.1.7.1.rc2', '< 4.2'], specifier_for['4.1.7.1.rc2']
-        assert_equal ['>= 4.2.0.beta1', '< 4.3'], specifier_for['4.2.0.beta1']
-        assert_equal ['>= 5.0.0.beta1', '< 5.1'], specifier_for['5.0.0.beta1']
+        assert_equal "~> 4.1.13", specifier_for["4.1.13"]
+        assert_equal "~> 4.1.6.rc1", specifier_for["4.1.6.rc1"]
+        assert_equal ["~> 4.1.7", ">= 4.1.7.1"], specifier_for["4.1.7.1"]
+        assert_equal ["~> 4.1.7", ">= 4.1.7.1.2"], specifier_for["4.1.7.1.2"]
+        assert_equal ["~> 4.1.7", ">= 4.1.7.1.rc2"], specifier_for["4.1.7.1.rc2"]
+        assert_equal "~> 4.2.0.beta1", specifier_for["4.2.0.beta1"]
+        assert_equal "~> 5.0.0.beta1", specifier_for["5.0.0.beta1"]
       end
     end
   end
diff --git a/railties/test/generators/generators_test_helper.rb b/railties/test/generators/generators_test_helper.rb
index b19a5a7144..ad2a55f496 100644
--- a/railties/test/generators/generators_test_helper.rb
+++ b/railties/test/generators/generators_test_helper.rb
@@ -1,15 +1,17 @@
-require 'abstract_unit'
-require 'active_support/core_ext/module/remove_method'
-require 'active_support/testing/stream'
-require 'active_support/testing/method_call_assertions'
-require 'rails/generators'
-require 'rails/generators/test_case'
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "active_support/core_ext/module/remove_method"
+require "active_support/testing/stream"
+require "active_support/testing/method_call_assertions"
+require "rails/generators"
+require "rails/generators/test_case"
 
 module Rails
   class << self
     remove_possible_method :root
     def root
-      @root ||= Pathname.new(File.expand_path('../../fixtures', __FILE__))
+      @root ||= Pathname.new(File.expand_path("../fixtures", __dir__))
     end
   end
 end
@@ -20,9 +22,9 @@ Rails.application.config.generators.templates = [File.join(Rails.root, "lib", "t
 # Rails.application.config.generators to Rails::Generators
 Rails.application.load_generators
 
-require 'active_record'
-require 'action_dispatch'
-require 'action_view'
+require "active_record"
+require "action_dispatch"
+require "action_view"
 
 module GeneratorsTestHelper
   include ActiveSupport::Testing::Stream
@@ -34,17 +36,16 @@ module GeneratorsTestHelper
       setup :prepare_destination
 
       begin
-        base.tests Rails::Generators.const_get(base.name.sub(/Test$/, ''))
+        base.tests Rails::Generators.const_get(base.name.sub(/Test$/, ""))
       rescue
       end
     end
   end
 
   def copy_routes
-    routes = File.expand_path("../../../lib/rails/generators/rails/app/templates/config/routes.rb", __FILE__)
+    routes = File.expand_path("../../lib/rails/generators/rails/app/templates/config/routes.rb.tt", __dir__)
     destination = File.join(destination_root, "config")
     FileUtils.mkdir_p(destination)
-    FileUtils.cp routes, destination
+    FileUtils.cp routes, File.join(destination, "routes.rb")
   end
-
 end
diff --git a/railties/test/generators/helper_generator_test.rb b/railties/test/generators/helper_generator_test.rb
index add04f21a4..4cdb6adf82 100644
--- a/railties/test/generators/helper_generator_test.rb
+++ b/railties/test/generators/helper_generator_test.rb
@@ -1,5 +1,7 @@
-require 'generators/generators_test_helper'
-require 'rails/generators/rails/helper/helper_generator'
+# frozen_string_literal: true
+
+require "generators/generators_test_helper"
+require "rails/generators/rails/helper/helper_generator"
 
 ObjectHelper = Class.new
 AnotherObjectHelperTest = Class.new
@@ -14,7 +16,7 @@ class HelperGeneratorTest < Rails::Generators::TestCase
   end
 
   def test_check_class_collision
-    content = capture(:stderr){ run_generator ["object"] }
+    content = capture(:stderr) { run_generator ["object"] }
     assert_match(/The name 'ObjectHelper' is either already used in your application or reserved/, content)
   end
 
diff --git a/railties/test/generators/integration_test_generator_test.rb b/railties/test/generators/integration_test_generator_test.rb
index d05ed76d24..82791f1a27 100644
--- a/railties/test/generators/integration_test_generator_test.rb
+++ b/railties/test/generators/integration_test_generator_test.rb
@@ -1,12 +1,18 @@
-require 'generators/generators_test_helper'
-require 'rails/generators/rails/integration_test/integration_test_generator'
+# frozen_string_literal: true
+
+require "generators/generators_test_helper"
+require "rails/generators/rails/integration_test/integration_test_generator"
 
 class IntegrationTestGeneratorTest < Rails::Generators::TestCase
   include GeneratorsTestHelper
-  arguments %w(integration)
 
   def test_integration_test_skeleton_is_created
-    run_generator
+    run_generator %w(integration)
     assert_file "test/integration/integration_test.rb", /class IntegrationTest < ActionDispatch::IntegrationTest/
   end
+
+  def test_namespaced_integration_test_skeleton_is_created
+    run_generator %w(iguchi/integration)
+    assert_file "test/integration/iguchi/integration_test.rb", /class Iguchi::IntegrationTest < ActionDispatch::IntegrationTest/
+  end
 end
diff --git a/railties/test/generators/job_generator_test.rb b/railties/test/generators/job_generator_test.rb
index dbff0ab704..13276fac65 100644
--- a/railties/test/generators/job_generator_test.rb
+++ b/railties/test/generators/job_generator_test.rb
@@ -1,5 +1,7 @@
-require 'generators/generators_test_helper'
-require 'rails/generators/job/job_generator'
+# frozen_string_literal: true
+
+require "generators/generators_test_helper"
+require "rails/generators/job/job_generator"
 
 class JobGeneratorTest < Rails::Generators::TestCase
   include GeneratorsTestHelper
diff --git a/railties/test/generators/mailer_generator_test.rb b/railties/test/generators/mailer_generator_test.rb
index 6a4951840d..ddac6e1a1e 100644
--- a/railties/test/generators/mailer_generator_test.rb
+++ b/railties/test/generators/mailer_generator_test.rb
@@ -1,5 +1,7 @@
-require 'generators/generators_test_helper'
-require 'rails/generators/mailer/mailer_generator'
+# frozen_string_literal: true
+
+require "generators/generators_test_helper"
+require "rails/generators/mailer/mailer_generator"
 
 class MailerGeneratorTest < Rails::Generators::TestCase
   include GeneratorsTestHelper
@@ -9,13 +11,13 @@ class MailerGeneratorTest < Rails::Generators::TestCase
     run_generator
     assert_file "app/mailers/notifier_mailer.rb" do |mailer|
       assert_match(/class NotifierMailer < ApplicationMailer/, mailer)
-      assert_no_match(/default from: "from@example.com"/, mailer)
+      assert_no_match(/default from: "from@example\.com"/, mailer)
       assert_no_match(/layout :mailer_notifier/, mailer)
     end
 
-    assert_file 'app/mailers/application_mailer.rb' do |mailer|
+    assert_file "app/mailers/application_mailer.rb" do |mailer|
       assert_match(/class ApplicationMailer < ActionMailer::Base/, mailer)
-      assert_match(/default from: 'from@example.com'/, mailer)
+      assert_match(/default from: 'from@example\.com'/, mailer)
       assert_match(/layout 'mailer'/, mailer)
     end
   end
@@ -30,7 +32,7 @@ class MailerGeneratorTest < Rails::Generators::TestCase
 
   def test_check_class_collision
     Object.send :const_set, :NotifierMailer, Class.new
-    content = capture(:stderr){ run_generator }
+    content = capture(:stderr) { run_generator }
     assert_match(/The name 'NotifierMailer' is either already used in your application or reserved/, content)
   ensure
     Object.send :remove_const, :NotifierMailer
@@ -48,18 +50,18 @@ class MailerGeneratorTest < Rails::Generators::TestCase
       assert_match(/class NotifierMailerPreview < ActionMailer::Preview/, preview)
       assert_match(/\# Preview this email at http:\/\/localhost\:3000\/rails\/mailers\/notifier_mailer\/foo/, preview)
       assert_instance_method :foo, preview do |foo|
-        assert_match(/NotifierMailer.foo/, foo)
+        assert_match(/NotifierMailer\.foo/, foo)
       end
       assert_match(/\# Preview this email at http:\/\/localhost\:3000\/rails\/mailers\/notifier_mailer\/bar/, preview)
       assert_instance_method :bar, preview do |bar|
-        assert_match(/NotifierMailer.bar/, bar)
+        assert_match(/NotifierMailer\.bar/, bar)
       end
     end
   end
 
   def test_check_test_class_collision
     Object.send :const_set, :NotifierMailerTest, Class.new
-    content = capture(:stderr){ run_generator }
+    content = capture(:stderr) { run_generator }
     assert_match(/The name 'NotifierMailerTest' is either already used in your application or reserved/, content)
   ensure
     Object.send :remove_const, :NotifierMailerTest
@@ -67,7 +69,7 @@ class MailerGeneratorTest < Rails::Generators::TestCase
 
   def test_check_preview_class_collision
     Object.send :const_set, :NotifierMailerPreview, Class.new
-    content = capture(:stderr){ run_generator }
+    content = capture(:stderr) { run_generator }
     assert_match(/The name 'NotifierMailerPreview' is either already used in your application or reserved/, content)
   ensure
     Object.send :remove_const, :NotifierMailerPreview
@@ -137,12 +139,12 @@ class MailerGeneratorTest < Rails::Generators::TestCase
 
     assert_file "app/mailers/notifier_mailer.rb" do |mailer|
       assert_instance_method :foo, mailer do |foo|
-        assert_match(/mail to: "to@example.org"/, foo)
+        assert_match(/mail to: "to@example\.org"/, foo)
         assert_match(/@greeting = "Hi"/, foo)
       end
 
       assert_instance_method :bar, mailer do |bar|
-        assert_match(/mail to: "to@example.org"/, bar)
+        assert_match(/mail to: "to@example\.org"/, bar)
         assert_match(/@greeting = "Hi"/, bar)
       end
     end
diff --git a/railties/test/generators/migration_generator_test.rb b/railties/test/generators/migration_generator_test.rb
index 46154b7db2..88a939a55a 100644
--- a/railties/test/generators/migration_generator_test.rb
+++ b/railties/test/generators/migration_generator_test.rb
@@ -1,5 +1,7 @@
-require 'generators/generators_test_helper'
-require 'rails/generators/rails/migration/migration_generator'
+# frozen_string_literal: true
+
+require "generators/generators_test_helper"
+require "rails/generators/rails/migration/migration_generator"
 
 class MigrationGeneratorTest < Rails::Generators::TestCase
   include GeneratorsTestHelper
@@ -17,7 +19,7 @@ class MigrationGeneratorTest < Rails::Generators::TestCase
       run_generator [migration]
       file_name = migration_file_name "db/migrate/#{migration}.rb"
 
-      File.basename(file_name).split('_').first
+      File.basename(file_name).split("_").first
     end
 
     assert_not_equal first_migration_number, second_migration_number
@@ -48,6 +50,17 @@ class MigrationGeneratorTest < Rails::Generators::TestCase
     end
   end
 
+  def test_add_migration_with_table_having_from_in_title
+    migration = "add_email_address_to_blacklisted_from_campaign"
+    run_generator [migration, "email_address:string"]
+
+    assert_migration "db/migrate/#{migration}.rb" do |content|
+      assert_method :change, content do |change|
+        assert_match(/add_column :blacklisted_from_campaigns, :email_address, :string/, change)
+      end
+    end
+  end
+
   def test_remove_migration_with_indexed_attribute
     migration = "remove_title_body_from_posts"
     run_generator [migration, "title:string:index", "body:text"]
@@ -73,6 +86,17 @@ class MigrationGeneratorTest < Rails::Generators::TestCase
     end
   end
 
+  def test_remove_migration_with_table_having_to_in_title
+    migration = "remove_email_address_from_sent_to_user"
+    run_generator [migration, "email_address:string"]
+
+    assert_migration "db/migrate/#{migration}.rb" do |content|
+      assert_method :change, content do |change|
+        assert_match(/remove_column :sent_to_users, :email_address, :string/, change)
+      end
+    end
+  end
+
   def test_remove_migration_with_references_options
     migration = "remove_references_from_books"
     run_generator [migration, "author:belongs_to", "distributor:references{polymorphic}"]
@@ -204,8 +228,8 @@ class MigrationGeneratorTest < Rails::Generators::TestCase
     assert_migration "db/migrate/#{migration}.rb" do |content|
       assert_method :change, content do |change|
         assert_match(/create_join_table :artists, :musics/, change)
-        assert_match(/# t.index \[:artist_id, :music_id\]/, change)
-        assert_match(/  t.index \[:music_id, :artist_id\], unique: true/, change)
+        assert_match(/# t\.index \[:artist_id, :music_id\]/, change)
+        assert_match(/  t\.index \[:music_id, :artist_id\], unique: true/, change)
       end
     end
   end
@@ -248,7 +272,7 @@ class MigrationGeneratorTest < Rails::Generators::TestCase
   def test_migration_with_singular_table_name
     with_singular_table_name do
       migration = "add_title_body_to_post"
-      run_generator [migration, 'title:string']
+      run_generator [migration, "title:string"]
       assert_migration "db/migrate/#{migration}.rb" do |content|
         assert_method :change, content do |change|
           assert_match(/add_column :post, :title, :string/, change)
@@ -265,8 +289,8 @@ class MigrationGeneratorTest < Rails::Generators::TestCase
       assert_migration "db/migrate/#{migration}.rb" do |content|
         assert_method :change, content do |change|
           assert_match(/create_join_table :artist, :music/, change)
-          assert_match(/# t.index \[:artist_id, :music_id\]/, change)
-          assert_match(/  t.index \[:music_id, :artist_id\], unique: true/, change)
+          assert_match(/# t\.index \[:artist_id, :music_id\]/, change)
+          assert_match(/  t\.index \[:music_id, :artist_id\], unique: true/, change)
         end
       end
     end
@@ -309,6 +333,17 @@ class MigrationGeneratorTest < Rails::Generators::TestCase
     end
   end
 
+  def test_add_migration_to_configured_path
+    old_paths = Rails.application.config.paths["db/migrate"]
+    Rails.application.config.paths.add "db/migrate", with: "db2/migrate"
+
+    migration = "migration_in_custom_path"
+    run_generator [migration]
+    assert_migration "db2/migrate/#{migration}.rb", /.*/
+  ensure
+    Rails.application.config.paths["db/migrate"] = old_paths
+  end
+
   private
 
     def with_singular_table_name
diff --git a/railties/test/generators/model_generator_test.rb b/railties/test/generators/model_generator_test.rb
index 6b30c40476..516aa0704f 100644
--- a/railties/test/generators/model_generator_test.rb
+++ b/railties/test/generators/model_generator_test.rb
@@ -1,19 +1,13 @@
-require 'generators/generators_test_helper'
-require 'rails/generators/rails/model/model_generator'
-require 'active_support/core_ext/string/strip'
+# frozen_string_literal: true
+
+require "generators/generators_test_helper"
+require "rails/generators/rails/model/model_generator"
+require "active_support/core_ext/string/strip"
 
 class ModelGeneratorTest < Rails::Generators::TestCase
   include GeneratorsTestHelper
   arguments %w(Account name:string age:integer)
 
-   def test_application_record_skeleton_is_created
-     run_generator
-     assert_file "app/models/application_record.rb" do |record|
-       assert_match(/class ApplicationRecord < ActiveRecord::Base/, record)
-       assert_match(/self.abstract_class = true/, record)
-     end
-   end
-
   def test_help_shows_invoked_generators_options
     content = run_generator ["--help"]
     assert_match(/ActiveRecord options:/, content)
@@ -43,17 +37,6 @@ class ModelGeneratorTest < Rails::Generators::TestCase
     assert_no_migration "db/migrate/create_accounts.rb"
   end
 
-  def test_model_with_existent_application_record
-    mkdir_p "#{destination_root}/app/models"
-    touch "#{destination_root}/app/models/application_record.rb"
-
-    Dir.chdir(destination_root) do
-      run_generator ["account"]
-    end
-
-    assert_file "app/models/account.rb", /class Account < ApplicationRecord/
-  end
-
   def test_plural_names_are_singularized
     content = run_generator ["accounts".freeze]
     assert_file "app/models/account.rb", /class Account < ApplicationRecord/
@@ -212,14 +195,25 @@ class ModelGeneratorTest < Rails::Generators::TestCase
   def test_migration_without_timestamps
     ActiveRecord::Base.timestamped_migrations = false
     run_generator ["account"]
-    assert_file  "db/migrate/001_create_accounts.rb", /class CreateAccounts < ActiveRecord::Migration\[[0-9.]+\]/
+    assert_file "db/migrate/001_create_accounts.rb", /class CreateAccounts < ActiveRecord::Migration\[[0-9.]+\]/
 
     run_generator ["project"]
-    assert_file  "db/migrate/002_create_projects.rb", /class CreateProjects < ActiveRecord::Migration\[[0-9.]+\]/
+    assert_file "db/migrate/002_create_projects.rb", /class CreateProjects < ActiveRecord::Migration\[[0-9.]+\]/
   ensure
     ActiveRecord::Base.timestamped_migrations = true
   end
 
+  def test_migration_with_configured_path
+    old_paths = Rails.application.config.paths["db/migrate"]
+    Rails.application.config.paths.add "db/migrate", with: "db2/migrate"
+
+    run_generator
+
+    assert_migration "db2/migrate/create_accounts.rb", /class CreateAccounts < ActiveRecord::Migration\[[0-9.]+\]/
+  ensure
+    Rails.application.config.paths["db/migrate"] = old_paths
+  end
+
   def test_model_with_references_attribute_generates_belongs_to_associations
     run_generator ["product", "name:string", "supplier:references"]
     assert_file "app/models/product.rb", /belongs_to :supplier/
@@ -242,7 +236,7 @@ class ModelGeneratorTest < Rails::Generators::TestCase
 
   def test_migration_with_timestamps
     run_generator
-    assert_migration "db/migrate/create_accounts.rb", /t.timestamps/
+    assert_migration "db/migrate/create_accounts.rb", /t\.timestamps/
   end
 
   def test_migration_timestamps_are_skipped
@@ -250,7 +244,7 @@ class ModelGeneratorTest < Rails::Generators::TestCase
 
     assert_migration "db/migrate/create_accounts.rb" do |m|
       assert_method :change, m do |up|
-        assert_no_match(/t.timestamps/, up)
+        assert_no_match(/t\.timestamps/, up)
       end
     end
   end
@@ -258,24 +252,24 @@ class ModelGeneratorTest < Rails::Generators::TestCase
   def test_migration_is_skipped_with_skip_option
     run_generator
     output = run_generator ["Account", "--skip"]
-    assert_match %r{skip\s+db/migrate/\d+_create_accounts.rb}, output
+    assert_match %r{skip\s+db/migrate/\d+_create_accounts\.rb}, output
   end
 
   def test_migration_is_ignored_as_identical_with_skip_option
     run_generator ["Account"]
     output = run_generator ["Account", "--skip"]
-    assert_match %r{identical\s+db/migrate/\d+_create_accounts.rb}, output
+    assert_match %r{identical\s+db/migrate/\d+_create_accounts\.rb}, output
   end
 
   def test_migration_is_skipped_on_skip_behavior
     run_generator
     output = run_generator ["Account"], behavior: :skip
-    assert_match %r{skip\s+db/migrate/\d+_create_accounts.rb}, output
+    assert_match %r{skip\s+db/migrate/\d+_create_accounts\.rb}, output
   end
 
   def test_migration_error_is_not_shown_on_revoke
     run_generator
-    error = capture(:stderr){ run_generator ["Account"], behavior: :revoke }
+    error = capture(:stderr) { run_generator ["Account"], behavior: :revoke }
     assert_no_match(/Another migration is already named create_accounts/, error)
   end
 
@@ -300,7 +294,7 @@ class ModelGeneratorTest < Rails::Generators::TestCase
 
     assert_file "test/fixtures/accounts.yml", /name: MyString/, /age: 1/
     assert_generated_fixture("test/fixtures/accounts.yml",
-                             {"one"=>{"name"=>"MyString", "age"=>1}, "two"=>{"name"=>"MyString", "age"=>1}})
+                             "one" => { "name" => "MyString", "age" => 1 }, "two" => { "name" => "MyString", "age" => 1 })
   end
 
   def test_fixtures_use_the_references_ids
@@ -308,7 +302,7 @@ class ModelGeneratorTest < Rails::Generators::TestCase
 
     assert_file "test/fixtures/line_items.yml", /product: one\n  cart: one/
     assert_generated_fixture("test/fixtures/line_items.yml",
-                             {"one"=>{"product"=>"one", "cart"=>"one"}, "two"=>{"product"=>"two", "cart"=>"two"}})
+                             "one" => { "product" => "one", "cart" => "one" }, "two" => { "product" => "two", "cart" => "two" })
   end
 
   def test_fixtures_use_the_references_ids_and_type
@@ -316,15 +310,15 @@ class ModelGeneratorTest < Rails::Generators::TestCase
 
     assert_file "test/fixtures/line_items.yml", /product: one\n  product_type: Product\n  cart: one/
     assert_generated_fixture("test/fixtures/line_items.yml",
-                             {"one"=>{"product"=>"one", "product_type"=>"Product", "cart"=>"one"},
-                              "two"=>{"product"=>"two", "product_type"=>"Product", "cart"=>"two"}})
+                             "one" => { "product" => "one", "product_type" => "Product", "cart" => "one" },
+                              "two" => { "product" => "two", "product_type" => "Product", "cart" => "two" })
   end
 
   def test_fixtures_respect_reserved_yml_keywords
     run_generator ["LineItem", "no:integer", "Off:boolean", "ON:boolean"]
 
     assert_generated_fixture("test/fixtures/line_items.yml",
-                             {"one"=>{"no"=>1, "Off"=>false, "ON"=>false}, "two"=>{"no"=>1, "Off"=>false, "ON"=>false}})
+                             "one" => { "no" => 1, "Off" => false, "ON" => false }, "two" => { "no" => 1, "Off" => false, "ON" => false })
   end
 
   def test_fixture_is_skipped
@@ -343,13 +337,13 @@ class ModelGeneratorTest < Rails::Generators::TestCase
     ActiveRecord::Base.pluralize_table_names = false
     run_generator
     assert_generated_fixture("test/fixtures/account.yml",
-                             {"one"=>{"name"=>"MyString", "age"=>1}, "two"=>{"name"=>"MyString", "age"=>1}})
+                             "one" => { "name" => "MyString", "age" => 1 }, "two" => { "name" => "MyString", "age" => 1 })
   ensure
     ActiveRecord::Base.pluralize_table_names = original_pluralize_table_name
   end
 
   def test_check_class_collision
-    content = capture(:stderr){ run_generator ["object"] }
+    content = capture(:stderr) { run_generator ["object"] }
     assert_match(/The name 'Object' is either already used in your application or reserved/, content)
   end
 
diff --git a/railties/test/generators/named_base_test.rb b/railties/test/generators/named_base_test.rb
index 291f5e06c3..4e61b660d7 100644
--- a/railties/test/generators/named_base_test.rb
+++ b/railties/test/generators/named_base_test.rb
@@ -1,84 +1,108 @@
-require 'generators/generators_test_helper'
-require 'rails/generators/rails/scaffold_controller/scaffold_controller_generator'
+# frozen_string_literal: true
+
+require "generators/generators_test_helper"
+require "rails/generators/rails/scaffold_controller/scaffold_controller_generator"
 
 class NamedBaseTest < Rails::Generators::TestCase
   include GeneratorsTestHelper
   tests Rails::Generators::ScaffoldControllerGenerator
 
   def test_named_generator_with_underscore
-    g = generator ['line_item']
-    assert_name g, 'line_item',  :name
+    g = generator ["line_item"]
+    assert_name g, "line_item",  :name
     assert_name g, %w(),         :class_path
-    assert_name g, 'LineItem',   :class_name
-    assert_name g, 'line_item',  :file_path
-    assert_name g, 'line_item',  :file_name
-    assert_name g, 'Line item',  :human_name
-    assert_name g, 'line_item',  :singular_name
-    assert_name g, 'line_items', :plural_name
-    assert_name g, 'line_item',  :i18n_scope
-    assert_name g, 'line_items', :table_name
+    assert_name g, "LineItem",   :class_name
+    assert_name g, "line_item",  :file_path
+    assert_name g, "line_item",  :file_name
+    assert_name g, "Line item",  :human_name
+    assert_name g, "line_item",  :singular_name
+    assert_name g, "line_items", :plural_name
+    assert_name g, "line_item",  :i18n_scope
+    assert_name g, "line_items", :table_name
   end
 
   def test_named_generator_attributes
-    g = generator ['admin/foo']
-    assert_name g, 'admin/foo',  :name
+    g = generator ["admin/foo"]
+    assert_name g, "admin/foo",  :name
     assert_name g, %w(admin),    :class_path
-    assert_name g, 'Admin::Foo', :class_name
-    assert_name g, 'admin/foo',  :file_path
-    assert_name g, 'foo',        :file_name
-    assert_name g, 'Foo',        :human_name
-    assert_name g, 'foo',        :singular_name
-    assert_name g, 'foos',       :plural_name
-    assert_name g, 'admin.foo',  :i18n_scope
-    assert_name g, 'admin_foos', :table_name
+    assert_name g, "Admin::Foo", :class_name
+    assert_name g, "admin/foo",  :file_path
+    assert_name g, "foo",        :file_name
+    assert_name g, "Foo",        :human_name
+    assert_name g, "foo",        :singular_name
+    assert_name g, "foos",       :plural_name
+    assert_name g, "admin.foo",  :i18n_scope
+    assert_name g, "admin_foos", :table_name
+    assert_name g, "admin/foos", :controller_name
+    assert_name g, %w(admin),     :controller_class_path
+    assert_name g, "Admin::Foos", :controller_class_name
+    assert_name g, "admin/foos",  :controller_file_path
+    assert_name g, "foos",        :controller_file_name
+    assert_name g, "admin.foos",  :controller_i18n_scope
+    assert_name g, "admin_foo",  :singular_route_name
+    assert_name g, "admin_foos", :plural_route_name
+    assert_name g, "@admin_foo", :redirect_resource_name
+    assert_name g, "admin_foo",  :model_resource_name
+    assert_name g, "admin_foos", :index_helper
   end
 
   def test_named_generator_attributes_as_ruby
-    g = generator ['Admin::Foo']
-    assert_name g, 'Admin::Foo', :name
+    g = generator ["Admin::Foo"]
+    assert_name g, "Admin::Foo", :name
     assert_name g, %w(admin),    :class_path
-    assert_name g, 'Admin::Foo', :class_name
-    assert_name g, 'admin/foo',  :file_path
-    assert_name g, 'foo',        :file_name
-    assert_name g, 'foo',        :singular_name
-    assert_name g, 'Foo',        :human_name
-    assert_name g, 'foos',       :plural_name
-    assert_name g, 'admin.foo',  :i18n_scope
-    assert_name g, 'admin_foos', :table_name
+    assert_name g, "Admin::Foo", :class_name
+    assert_name g, "admin/foo",  :file_path
+    assert_name g, "foo",        :file_name
+    assert_name g, "foo",        :singular_name
+    assert_name g, "Foo",        :human_name
+    assert_name g, "foos",       :plural_name
+    assert_name g, "admin.foo",  :i18n_scope
+    assert_name g, "admin_foos", :table_name
+    assert_name g, "Admin::Foos", :controller_name
+    assert_name g, %w(admin),     :controller_class_path
+    assert_name g, "Admin::Foos", :controller_class_name
+    assert_name g, "admin/foos",  :controller_file_path
+    assert_name g, "foos",        :controller_file_name
+    assert_name g, "admin.foos",  :controller_i18n_scope
+    assert_name g, "admin_foo",  :singular_route_name
+    assert_name g, "admin_foos", :plural_route_name
+    assert_name g, "@admin_foo", :redirect_resource_name
+    assert_name g, "admin_foo",  :model_resource_name
+    assert_name g, "admin_foos", :index_helper
   end
 
   def test_named_generator_attributes_without_pluralized
     original_pluralize_table_names = ActiveRecord::Base.pluralize_table_names
     ActiveRecord::Base.pluralize_table_names = false
 
-    g = generator ['admin/foo']
-    assert_name g, 'admin_foo', :table_name
+    g = generator ["admin/foo"]
+    assert_name g, "admin_foo", :table_name
   ensure
     ActiveRecord::Base.pluralize_table_names = original_pluralize_table_names
   end
 
-  def test_scaffold_plural_names
-    g = generator ['admin/foo']
-    assert_name g, 'admin/foos',  :controller_name
+  def test_namespaced_scaffold_plural_names
+    g = generator ["admin/foo"]
+    assert_name g, "admin/foos",  :controller_name
     assert_name g, %w(admin),     :controller_class_path
-    assert_name g, 'Admin::Foos', :controller_class_name
-    assert_name g, 'admin/foos',  :controller_file_path
-    assert_name g, 'foos',        :controller_file_name
-    assert_name g, 'admin.foos',  :controller_i18n_scope
+    assert_name g, "Admin::Foos", :controller_class_name
+    assert_name g, "admin/foos",  :controller_file_path
+    assert_name g, "foos",        :controller_file_name
+    assert_name g, "admin.foos",  :controller_i18n_scope
   end
 
-  def test_scaffold_plural_names_as_ruby
-    g = generator ['Admin::Foo']
-    assert_name g, 'Admin::Foos', :controller_name
+  def test_namespaced_scaffold_plural_names_as_ruby
+    g = generator ["Admin::Foo"]
+    assert_name g, "Admin::Foos", :controller_name
     assert_name g, %w(admin),     :controller_class_path
-    assert_name g, 'Admin::Foos', :controller_class_name
-    assert_name g, 'admin/foos',  :controller_file_path
-    assert_name g, 'foos',        :controller_file_name
-    assert_name g, 'admin.foos',  :controller_i18n_scope
+    assert_name g, "Admin::Foos", :controller_class_name
+    assert_name g, "admin/foos",  :controller_file_path
+    assert_name g, "foos",        :controller_file_name
+    assert_name g, "admin.foos",  :controller_i18n_scope
   end
 
   def test_application_name
-    g = generator ['Admin::Foo']
+    g = generator ["Admin::Foo"]
     Rails.stub(:application, Object.new) do
       assert_name g, "object", :application_name
     end
@@ -89,49 +113,62 @@ class NamedBaseTest < Rails::Generators::TestCase
   end
 
   def test_index_helper
-    g = generator ['Post']
-    assert_name g, 'posts', :index_helper
+    g = generator ["Post"]
+    assert_name g, "posts", :index_helper
   end
 
   def test_index_helper_to_pluralize_once
-    g = generator ['Stadium']
-    assert_name g, 'stadia', :index_helper
+    g = generator ["Stadium"]
+    assert_name g, "stadia", :index_helper
   end
 
   def test_index_helper_with_uncountable
-    g = generator ['Sheep']
-    assert_name g, 'sheep_index', :index_helper
+    g = generator ["Sheep"]
+    assert_name g, "sheep_index", :index_helper
   end
 
   def test_hide_namespace
-    g = generator ['Hidden']
-    g.class.stub(:namespace, 'hidden') do
-      assert !Rails::Generators.hidden_namespaces.include?('hidden')
+    g = generator ["Hidden"]
+    g.class.stub(:namespace, "hidden") do
+      assert_not_includes Rails::Generators.hidden_namespaces, "hidden"
       g.class.hide!
-      assert Rails::Generators.hidden_namespaces.include?('hidden')
+      assert_includes Rails::Generators.hidden_namespaces, "hidden"
     end
   end
 
   def test_scaffold_plural_names_with_model_name_option
-    g = generator ['Admin::Foo'], model_name: 'User'
-    assert_name g, 'user',        :singular_name
-    assert_name g, 'User',        :name
-    assert_name g, 'user',        :file_path
-    assert_name g, 'User',        :class_name
-    assert_name g, 'user',        :file_name
-    assert_name g, 'User',        :human_name
-    assert_name g, 'users',       :plural_name
-    assert_name g, 'user',        :i18n_scope
-    assert_name g, 'users',       :table_name
-    assert_name g, 'Admin::Foos', :controller_name
+    g = generator ["Admin::Foo"], model_name: "User"
+    assert_name g, "user",        :singular_name
+    assert_name g, "User",        :name
+    assert_name g, "user",        :file_path
+    assert_name g, "User",        :class_name
+    assert_name g, "user",        :file_name
+    assert_name g, "User",        :human_name
+    assert_name g, "users",       :plural_name
+    assert_name g, "user",        :i18n_scope
+    assert_name g, "users",       :table_name
+    assert_name g, "Admin::Foos", :controller_name
     assert_name g, %w(admin),     :controller_class_path
-    assert_name g, 'Admin::Foos', :controller_class_name
-    assert_name g, 'admin/foos',  :controller_file_path
-    assert_name g, 'foos',        :controller_file_name
-    assert_name g, 'admin.foos',  :controller_i18n_scope
+    assert_name g, "Admin::Foos", :controller_class_name
+    assert_name g, "admin/foos",  :controller_file_path
+    assert_name g, "foos",        :controller_file_name
+    assert_name g, "admin.foos",  :controller_i18n_scope
+    assert_name g, "admin_user",  :singular_route_name
+    assert_name g, "admin_users", :plural_route_name
+    assert_name g, "[:admin, @user]", :redirect_resource_name
+    assert_name g, "[:admin, user]",  :model_resource_name
+    assert_name g, "admin_users", :index_helper
+  end
+
+  def test_scaffold_plural_names
+    g = generator ["User"]
+    assert_name g, "@user", :redirect_resource_name
+    assert_name g, "user",  :model_resource_name
+    assert_name g, "user",  :singular_route_name
+    assert_name g, "users", :plural_route_name
   end
 
-  protected
+  private
 
     def assert_name(generator, value, method)
       assert_equal value, generator.send(method)
diff --git a/railties/test/generators/namespaced_generators_test.rb b/railties/test/generators/namespaced_generators_test.rb
index 902c340321..4b75a31f17 100644
--- a/railties/test/generators/namespaced_generators_test.rb
+++ b/railties/test/generators/namespaced_generators_test.rb
@@ -1,8 +1,11 @@
-require 'generators/generators_test_helper'
-require 'rails/generators/rails/controller/controller_generator'
-require 'rails/generators/rails/model/model_generator'
-require 'rails/generators/mailer/mailer_generator'
-require 'rails/generators/rails/scaffold/scaffold_generator'
+# frozen_string_literal: true
+
+require "generators/generators_test_helper"
+require "rails/generators/rails/controller/controller_generator"
+require "rails/generators/rails/model/model_generator"
+require "rails/generators/mailer/mailer_generator"
+require "rails/generators/rails/scaffold/scaffold_generator"
+require "rails/generators/rails/application_record/application_record_generator"
 
 class NamespacedGeneratorTestCase < Rails::Generators::TestCase
   include GeneratorsTestHelper
@@ -149,7 +152,7 @@ class NamespacedMailerGeneratorTest < NamespacedGeneratorTestCase
     assert_file "app/mailers/test_app/notifier_mailer.rb" do |mailer|
       assert_match(/module TestApp/, mailer)
       assert_match(/class NotifierMailer < ApplicationMailer/, mailer)
-      assert_no_match(/default from: "from@example.com"/, mailer)
+      assert_no_match(/default from: "from@example\.com"/, mailer)
     end
   end
 
@@ -421,3 +424,13 @@ class NamespacedScaffoldGeneratorTest < NamespacedGeneratorTestCase
                 /module TestApp\n  class Admin::RolesControllerTest < ActionDispatch::IntegrationTest/
   end
 end
+
+class NamespacedApplicationRecordGeneratorTest < NamespacedGeneratorTestCase
+  include GeneratorsTestHelper
+  tests Rails::Generators::ApplicationRecordGenerator
+
+  def test_adds_namespace_to_application_record
+    run_generator
+    assert_file "app/models/test_app/application_record.rb", /module TestApp/, /  class ApplicationRecord < ActiveRecord::Base/
+  end
+end
diff --git a/railties/test/generators/orm_test.rb b/railties/test/generators/orm_test.rb
index 88ae930554..6eaf2fbfd3 100644
--- a/railties/test/generators/orm_test.rb
+++ b/railties/test/generators/orm_test.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require "generators/generators_test_helper"
 require "rails/generators/rails/scaffold_controller/scaffold_controller_generator"
 
diff --git a/railties/test/generators/plugin_generator_test.rb b/railties/test/generators/plugin_generator_test.rb
index 5dd4cce28a..fc7584c175 100644
--- a/railties/test/generators/plugin_generator_test.rb
+++ b/railties/test/generators/plugin_generator_test.rb
@@ -1,6 +1,9 @@
-require 'generators/generators_test_helper'
-require 'rails/generators/rails/plugin/plugin_generator'
-require 'generators/shared_generator_tests'
+# frozen_string_literal: true
+
+require "generators/generators_test_helper"
+require "rails/generators/rails/plugin/plugin_generator"
+require "generators/shared_generator_tests"
+require "rails/engine/updater"
 
 DEFAULT_PLUGIN_FILES = %w(
   .gitignore
@@ -23,23 +26,27 @@ class PluginGeneratorTest < Rails::Generators::TestCase
   destination File.join(Rails.root, "tmp/bukkits")
   arguments [destination_root]
 
+  def application_path
+    "#{destination_root}/test/dummy"
+  end
+
   # brings setup, teardown, and some tests
   include SharedGeneratorTests
 
   def test_invalid_plugin_name_raises_an_error
-    content = capture(:stderr){ run_generator [File.join(destination_root, "my_plugin-31fr-extension")] }
+    content = capture(:stderr) { run_generator [File.join(destination_root, "my_plugin-31fr-extension")] }
     assert_equal "Invalid plugin name my_plugin-31fr-extension. Please give a name which does not contain a namespace starting with numeric characters.\n", content
 
-    content = capture(:stderr){ run_generator [File.join(destination_root, "things4.3")] }
+    content = capture(:stderr) { run_generator [File.join(destination_root, "things4.3")] }
     assert_equal "Invalid plugin name things4.3. Please give a name which uses only alphabetic, numeric, \"_\" or \"-\" characters.\n", content
 
-    content = capture(:stderr){ run_generator [File.join(destination_root, "43things")] }
+    content = capture(:stderr) { run_generator [File.join(destination_root, "43things")] }
     assert_equal "Invalid plugin name 43things. Please give a name which does not start with numbers.\n", content
 
-    content = capture(:stderr){ run_generator [File.join(destination_root, "plugin")] }
+    content = capture(:stderr) { run_generator [File.join(destination_root, "plugin")] }
     assert_equal "Invalid plugin name plugin. Please give a name which does not match one of the reserved rails words: application, destroy, plugin, runner, test\n", content
 
-    content = capture(:stderr){ run_generator [File.join(destination_root, "Digest")] }
+    content = capture(:stderr) { run_generator [File.join(destination_root, "Digest")] }
     assert_equal "Invalid plugin name Digest, constant Digest is already in use. Please choose another plugin name.\n", content
   end
 
@@ -47,7 +54,7 @@ class PluginGeneratorTest < Rails::Generators::TestCase
     run_generator [File.join(destination_root, "hyphenated-name")]
     assert_no_file "hyphenated-name/lib/hyphenated-name.rb"
     assert_no_file "hyphenated-name/lib/hyphenated_name.rb"
-    assert_file "hyphenated-name/lib/hyphenated/name.rb", /module Hyphenated\n  module Name\n    # Your code goes here...\n  end\nend/
+    assert_file "hyphenated-name/lib/hyphenated/name.rb", /module Hyphenated\n  module Name\n    # Your code goes here\.\.\.\n  end\nend/
   end
 
   def test_correct_file_in_lib_folder_of_camelcase_plugin_name
@@ -62,14 +69,28 @@ class PluginGeneratorTest < Rails::Generators::TestCase
     assert_no_file "config/routes.rb"
     assert_no_file "app/assets/config/bukkits_manifest.js"
     assert_file "test/test_helper.rb" do |content|
-      assert_match(/require.+test\/dummy\/config\/environment/, content)
+      assert_match(/require_relative.+test\/dummy\/config\/environment/, content)
       assert_match(/ActiveRecord::Migrator\.migrations_paths.+test\/dummy\/db\/migrate/, content)
       assert_match(/Minitest\.backtrace_filter = Minitest::BacktraceFilter\.new/, content)
       assert_match(/Rails::TestUnitReporter\.executable = 'bin\/test'/, content)
     end
+    assert_file "lib/bukkits/railtie.rb", /module Bukkits\n  class Railtie < ::Rails::Railtie\n  end\nend/
+    assert_file "lib/bukkits.rb", /require "bukkits\/railtie"/
     assert_file "test/bukkits_test.rb", /assert_kind_of Module, Bukkits/
-    assert_file 'bin/test'
-    assert_no_file 'bin/rails'
+    assert_file "bin/test"
+    assert_no_file "bin/rails"
+  end
+
+  def test_generating_in_full_mode_with_almost_of_all_skip_options
+    run_generator [destination_root, "--full", "-M", "-O", "-C", "-S", "-T"]
+    assert_file "bin/rails" do |content|
+      assert_no_match(/\s+require\s+["']rails\/all["']/, content)
+    end
+    assert_file "bin/rails", /#\s+require\s+["']active_record\/railtie["']/
+    assert_file "bin/rails", /#\s+require\s+["']action_mailer\/railtie["']/
+    assert_file "bin/rails", /#\s+require\s+["']action_cable\/engine["']/
+    assert_file "bin/rails", /#\s+require\s+["']sprockets\/railtie["']/
+    assert_file "bin/rails", /#\s+require\s+["']rails\/test_unit\/railtie["']/
   end
 
   def test_generating_test_files_in_full_mode
@@ -79,8 +100,13 @@ class PluginGeneratorTest < Rails::Generators::TestCase
     assert_file "test/integration/navigation_test.rb", /ActionDispatch::IntegrationTest/
   end
 
+  def test_inclusion_of_git_source
+    run_generator [destination_root]
+    assert_file "Gemfile", /git_source/
+  end
+
   def test_inclusion_of_a_debugger
-    run_generator [destination_root, '--full']
+    run_generator [destination_root, "--full"]
     if defined?(JRUBY_VERSION) || RUBY_ENGINE == "rbx"
       assert_file "Gemfile" do |content|
         assert_no_match(/byebug/, content)
@@ -94,15 +120,19 @@ class PluginGeneratorTest < Rails::Generators::TestCase
     run_generator [destination_root, "-T", "--full"]
 
     assert_no_directory "test/integration/"
-    assert_no_file "test"
+    assert_no_directory "test"
     assert_file "Rakefile" do |contents|
       assert_no_match(/APP_RAKEFILE/, contents)
     end
+    assert_file "bin/rails" do |contents|
+      assert_no_match(/APP_PATH/, contents)
+    end
   end
 
   def test_generating_adds_dummy_app_rake_tasks_without_unit_test_files
-    run_generator [destination_root, "-T", "--mountable", '--dummy-path', 'my_dummy_app']
+    run_generator [destination_root, "-T", "--mountable", "--dummy-path", "my_dummy_app"]
     assert_file "Rakefile", /APP_RAKEFILE/
+    assert_file "bin/rails", /APP_PATH/
   end
 
   def test_generating_adds_dummy_app_without_javascript_and_assets_deps
@@ -123,8 +153,8 @@ class PluginGeneratorTest < Rails::Generators::TestCase
   def test_ensure_that_test_dummy_can_be_generated_from_a_template
     FileUtils.cd(Rails.root)
     run_generator([destination_root, "-m", "lib/create_test_dummy_template.rb", "--skip-test"])
-    assert_file "spec/dummy"
-    assert_no_file "test"
+    assert_directory "spec/dummy"
+    assert_no_directory "test"
   end
 
   def test_database_entry_is_generated_for_sqlite3_by_default_in_full_mode
@@ -143,63 +173,40 @@ class PluginGeneratorTest < Rails::Generators::TestCase
     run_generator [destination_root, "--skip-active-record"]
 
     assert_file "bukkits.gemspec" do |contents|
-      assert_no_match(/s.add_development_dependency "sqlite3"/, contents)
+      assert_no_match(/s\.add_development_dependency "sqlite3"/, contents)
     end
   end
 
-  def test_app_generator_without_skips
-    run_generator
-    assert_file "test/dummy/config/application.rb", /\s+require\s+["']rails\/all["']/
-    assert_file "test/dummy/config/environments/development.rb" do |content|
-      assert_match(/config\.action_mailer\.raise_delivery_errors = false/, content)
-    end
-    assert_file "test/dummy/config/environments/test.rb" do |content|
-      assert_match(/config\.action_mailer\.delivery_method = :test/, content)
-    end
-    assert_file "test/dummy/config/environments/production.rb" do |content|
-      assert_match(/# config\.action_mailer\.raise_delivery_errors = false/, content)
-    end
-  end
-
-  def test_active_record_is_removed_from_frameworks_if_skip_active_record_is_given
-    run_generator [destination_root, "--skip-active-record"]
-    assert_file "test/dummy/config/application.rb", /#\s+require\s+["']active_record\/railtie["']/
-  end
-
   def test_ensure_that_skip_active_record_option_is_passed_to_app_generator
     run_generator [destination_root, "--skip_active_record"]
-    assert_no_file "test/dummy/config/database.yml"
     assert_file "test/test_helper.rb" do |contents|
       assert_no_match(/ActiveRecord/, contents)
     end
   end
 
-  def test_action_mailer_is_removed_from_frameworks_if_skip_action_mailer_is_given
-    run_generator [destination_root, "--skip-action-mailer"]
-    assert_file "test/dummy/config/application.rb", /#\s+require\s+["']action_mailer\/railtie["']/
-    assert_file "test/dummy/config/environments/development.rb" do |content|
-      assert_no_match(/config\.action_mailer/, content)
-    end
-    assert_file "test/dummy/config/environments/test.rb" do |content|
-      assert_no_match(/config\.action_mailer/, content)
-    end
-    assert_file "test/dummy/config/environments/production.rb" do |content|
-      assert_no_match(/config\.action_mailer/, content)
-    end
-  end
-
   def test_ensure_that_database_option_is_passed_to_app_generator
     run_generator [destination_root, "--database", "postgresql"]
     assert_file "test/dummy/config/database.yml", /postgres/
   end
 
-  def test_generation_runs_bundle_install_with_full_and_mountable
-    result = run_generator [destination_root, "--mountable", "--full", "--dev"]
-    assert_match(/run  bundle install/, result)
-    assert $?.success?, "Command failed: #{result}"
-    assert_file "#{destination_root}/Gemfile.lock" do |contents|
-      assert_match(/bukkits/, contents)
-    end
+  def test_generation_runs_bundle_install
+    assert_generates_without_bundler
+  end
+
+  def test_dev_option
+    assert_generates_without_bundler(dev: true)
+    rails_path = File.expand_path("../../..", Rails.root)
+    assert_file "Gemfile", /^gem\s+["']rails["'],\s+path:\s+["']#{Regexp.escape(rails_path)}["']$/
+  end
+
+  def test_edge_option
+    assert_generates_without_bundler(edge: true)
+    assert_file "Gemfile", %r{^gem\s+["']rails["'],\s+github:\s+["']#{Regexp.escape("rails/rails")}["']$}
+  end
+
+  def test_generation_does_not_run_bundle_install_with_full_and_mountable
+    assert_generates_without_bundler(mountable: true, full: true, dev: true)
+    assert_no_file "#{destination_root}/Gemfile.lock"
   end
 
   def test_skipping_javascripts_without_mountable_option
@@ -225,21 +232,21 @@ class PluginGeneratorTest < Rails::Generators::TestCase
   def test_ensure_that_tests_work
     run_generator
     FileUtils.cd destination_root
-    quietly { system 'bundle install' }
+    quietly { system "bundle install" }
     assert_match(/1 runs, 1 assertions, 0 failures, 0 errors/, `bin/test 2>&1`)
   end
 
   def test_ensure_that_tests_works_in_full_mode
     run_generator [destination_root, "--full", "--skip_active_record"]
     FileUtils.cd destination_root
-    quietly { system 'bundle install' }
+    quietly { system "bundle install" }
     assert_match(/1 runs, 1 assertions, 0 failures, 0 errors/, `bundle exec rake test 2>&1`)
   end
 
   def test_ensure_that_migration_tasks_work_with_mountable_option
     run_generator [destination_root, "--mountable"]
     FileUtils.cd destination_root
-    quietly { system 'bundle install' }
+    quietly { system "bundle install" }
     output = `bin/rails db:migrate 2>&1`
     assert $?.success?, "Command failed: #{output}"
   end
@@ -254,7 +261,7 @@ class PluginGeneratorTest < Rails::Generators::TestCase
     assert_file "app/views"
     assert_file "app/helpers"
     assert_file "app/mailers"
-    assert_file "bin/rails"
+    assert_file "bin/rails", /\s+require\s+["']rails\/all["']/
     assert_file "config/routes.rb", /Rails.application.routes.draw do/
     assert_file "lib/bukkits/engine.rb", /module Bukkits\n  class Engine < ::Rails::Engine\n  end\nend/
     assert_file "lib/bukkits.rb", /require "bukkits\/engine"/
@@ -274,7 +281,7 @@ class PluginGeneratorTest < Rails::Generators::TestCase
     assert_file "hyphenated-name/config/routes.rb",              /Rails.application.routes.draw do/
     assert_file "hyphenated-name/lib/hyphenated/name/engine.rb", /module Hyphenated\n  module Name\n    class Engine < ::Rails::Engine\n    end\n  end\nend/
     assert_file "hyphenated-name/lib/hyphenated/name.rb",        /require "hyphenated\/name\/engine"/
-    assert_file "hyphenated-name/bin/rails",                     /\.\.\/\.\.\/lib\/hyphenated\/name\/engine/
+    assert_file "hyphenated-name/bin/rails",                     /\.\.\/lib\/hyphenated\/name\/engine/
   end
 
   def test_creating_engine_with_hyphenated_and_underscored_name_in_full_mode
@@ -288,14 +295,14 @@ class PluginGeneratorTest < Rails::Generators::TestCase
     assert_file "my_hyphenated-name/app/helpers"
     assert_file "my_hyphenated-name/app/mailers"
     assert_file "my_hyphenated-name/bin/rails"
-    assert_file "my_hyphenated-name/config/routes.rb",              /Rails.application.routes.draw do/
+    assert_file "my_hyphenated-name/config/routes.rb",              /Rails\.application\.routes\.draw do/
     assert_file "my_hyphenated-name/lib/my_hyphenated/name/engine.rb", /module MyHyphenated\n  module Name\n    class Engine < ::Rails::Engine\n    end\n  end\nend/
     assert_file "my_hyphenated-name/lib/my_hyphenated/name.rb",        /require "my_hyphenated\/name\/engine"/
-    assert_file "my_hyphenated-name/bin/rails",                     /\.\.\/\.\.\/lib\/my_hyphenated\/name\/engine/
+    assert_file "my_hyphenated-name/bin/rails",                     /\.\.\/lib\/my_hyphenated\/name\/engine/
   end
 
   def test_being_quiet_while_creating_dummy_application
-    assert_no_match(/create\s+config\/application.rb/, run_generator)
+    assert_no_match(/create\s+config\/application\.rb/, run_generator)
   end
 
   def test_create_mountable_application_with_mountable_option
@@ -303,13 +310,13 @@ class PluginGeneratorTest < Rails::Generators::TestCase
     assert_file "app/assets/javascripts/bukkits"
     assert_file "app/assets/stylesheets/bukkits"
     assert_file "app/assets/images/bukkits"
-    assert_file "config/routes.rb", /Bukkits::Engine.routes.draw do/
+    assert_file "config/routes.rb", /Bukkits::Engine\.routes\.draw do/
     assert_file "lib/bukkits/engine.rb", /isolate_namespace Bukkits/
     assert_file "test/dummy/config/routes.rb", /mount Bukkits::Engine => "\/bukkits"/
     assert_file "app/controllers/bukkits/application_controller.rb", /module Bukkits\n  class ApplicationController < ActionController::Base/
     assert_file "app/models/bukkits/application_record.rb", /module Bukkits\n  class ApplicationRecord < ActiveRecord::Base/
     assert_file "app/jobs/bukkits/application_job.rb", /module Bukkits\n  class ApplicationJob < ActiveJob::Base/
-    assert_file "app/mailers/bukkits/application_mailer.rb", /module Bukkits\n  class ApplicationMailer < ActionMailer::Base\n    default from: 'from@example.com'\n    layout 'mailer'\n/
+    assert_file "app/mailers/bukkits/application_mailer.rb", /module Bukkits\n  class ApplicationMailer < ActionMailer::Base\n    default from: 'from@example\.com'\n    layout 'mailer'\n/
     assert_file "app/helpers/bukkits/application_helper.rb", /module Bukkits\n  module ApplicationHelper/
     assert_file "app/views/layouts/bukkits/application.html.erb" do |contents|
       assert_match "<title>Bukkits</title>", contents
@@ -322,7 +329,7 @@ class PluginGeneratorTest < Rails::Generators::TestCase
       assert_match(/ActionDispatch::IntegrationTest\.fixture_path = ActiveSupport::TestCase\.fixture_pat/, content)
       assert_no_match(/Rails::TestUnitReporter\.executable = 'bin\/test'/, content)
     end
-    assert_no_file 'bin/test'
+    assert_no_file "bin/test"
   end
 
   def test_create_mountable_application_with_mountable_option_and_hypenated_name
@@ -330,15 +337,15 @@ class PluginGeneratorTest < Rails::Generators::TestCase
     assert_file "hyphenated-name/app/assets/javascripts/hyphenated/name"
     assert_file "hyphenated-name/app/assets/stylesheets/hyphenated/name"
     assert_file "hyphenated-name/app/assets/images/hyphenated/name"
-    assert_file "hyphenated-name/config/routes.rb",                                          /Hyphenated::Name::Engine.routes.draw do/
-    assert_file "hyphenated-name/lib/hyphenated/name/version.rb",                            /module Hyphenated\n  module Name\n    VERSION = '0.1.0'\n  end\nend/
+    assert_file "hyphenated-name/config/routes.rb",                                          /Hyphenated::Name::Engine\.routes\.draw do/
+    assert_file "hyphenated-name/lib/hyphenated/name/version.rb",                            /module Hyphenated\n  module Name\n    VERSION = '0\.1\.0'\n  end\nend/
     assert_file "hyphenated-name/lib/hyphenated/name/engine.rb",                             /module Hyphenated\n  module Name\n    class Engine < ::Rails::Engine\n      isolate_namespace Hyphenated::Name\n    end\n  end\nend/
     assert_file "hyphenated-name/lib/hyphenated/name.rb",                                    /require "hyphenated\/name\/engine"/
     assert_file "hyphenated-name/test/dummy/config/routes.rb",                               /mount Hyphenated::Name::Engine => "\/hyphenated-name"/
     assert_file "hyphenated-name/app/controllers/hyphenated/name/application_controller.rb", /module Hyphenated\n  module Name\n    class ApplicationController < ActionController::Base\n      protect_from_forgery with: :exception\n    end\n  end\nend\n/
     assert_file "hyphenated-name/app/models/hyphenated/name/application_record.rb",          /module Hyphenated\n  module Name\n    class ApplicationRecord < ActiveRecord::Base\n      self\.abstract_class = true\n    end\n  end\nend/
     assert_file "hyphenated-name/app/jobs/hyphenated/name/application_job.rb",               /module Hyphenated\n  module Name\n    class ApplicationJob < ActiveJob::Base/
-    assert_file "hyphenated-name/app/mailers/hyphenated/name/application_mailer.rb",         /module Hyphenated\n  module Name\n    class ApplicationMailer < ActionMailer::Base\n      default from: 'from@example.com'\n      layout 'mailer'\n    end\n  end\nend/
+    assert_file "hyphenated-name/app/mailers/hyphenated/name/application_mailer.rb",         /module Hyphenated\n  module Name\n    class ApplicationMailer < ActionMailer::Base\n      default from: 'from@example\.com'\n      layout 'mailer'\n    end\n  end\nend/
     assert_file "hyphenated-name/app/helpers/hyphenated/name/application_helper.rb",         /module Hyphenated\n  module Name\n    module ApplicationHelper\n    end\n  end\nend/
     assert_file "hyphenated-name/app/views/layouts/hyphenated/name/application.html.erb" do |contents|
       assert_match "<title>Hyphenated name</title>", contents
@@ -352,15 +359,15 @@ class PluginGeneratorTest < Rails::Generators::TestCase
     assert_file "my_hyphenated-name/app/assets/javascripts/my_hyphenated/name"
     assert_file "my_hyphenated-name/app/assets/stylesheets/my_hyphenated/name"
     assert_file "my_hyphenated-name/app/assets/images/my_hyphenated/name"
-    assert_file "my_hyphenated-name/config/routes.rb",                                             /MyHyphenated::Name::Engine.routes.draw do/
-    assert_file "my_hyphenated-name/lib/my_hyphenated/name/version.rb",                            /module MyHyphenated\n  module Name\n    VERSION = '0.1.0'\n  end\nend/
+    assert_file "my_hyphenated-name/config/routes.rb",                                             /MyHyphenated::Name::Engine\.routes\.draw do/
+    assert_file "my_hyphenated-name/lib/my_hyphenated/name/version.rb",                            /module MyHyphenated\n  module Name\n    VERSION = '0\.1\.0'\n  end\nend/
     assert_file "my_hyphenated-name/lib/my_hyphenated/name/engine.rb",                             /module MyHyphenated\n  module Name\n    class Engine < ::Rails::Engine\n      isolate_namespace MyHyphenated::Name\n    end\n  end\nend/
     assert_file "my_hyphenated-name/lib/my_hyphenated/name.rb",                                    /require "my_hyphenated\/name\/engine"/
     assert_file "my_hyphenated-name/test/dummy/config/routes.rb",                                  /mount MyHyphenated::Name::Engine => "\/my_hyphenated-name"/
     assert_file "my_hyphenated-name/app/controllers/my_hyphenated/name/application_controller.rb", /module MyHyphenated\n  module Name\n    class ApplicationController < ActionController::Base\n      protect_from_forgery with: :exception\n    end\n  end\nend\n/
     assert_file "my_hyphenated-name/app/models/my_hyphenated/name/application_record.rb",          /module MyHyphenated\n  module Name\n    class ApplicationRecord < ActiveRecord::Base\n      self\.abstract_class = true\n    end\n  end\nend/
     assert_file "my_hyphenated-name/app/jobs/my_hyphenated/name/application_job.rb",               /module MyHyphenated\n  module Name\n    class ApplicationJob < ActiveJob::Base/
-    assert_file "my_hyphenated-name/app/mailers/my_hyphenated/name/application_mailer.rb",         /module MyHyphenated\n  module Name\n    class ApplicationMailer < ActionMailer::Base\n      default from: 'from@example.com'\n      layout 'mailer'\n    end\n  end\nend/
+    assert_file "my_hyphenated-name/app/mailers/my_hyphenated/name/application_mailer.rb",         /module MyHyphenated\n  module Name\n    class ApplicationMailer < ActionMailer::Base\n      default from: 'from@example\.com'\n      layout 'mailer'\n    end\n  end\nend/
     assert_file "my_hyphenated-name/app/helpers/my_hyphenated/name/application_helper.rb",         /module MyHyphenated\n  module Name\n    module ApplicationHelper\n    end\n  end\nend/
     assert_file "my_hyphenated-name/app/views/layouts/my_hyphenated/name/application.html.erb" do |contents|
       assert_match "<title>My hyphenated name</title>", contents
@@ -374,15 +381,15 @@ class PluginGeneratorTest < Rails::Generators::TestCase
     assert_file "deep-hyphenated-name/app/assets/javascripts/deep/hyphenated/name"
     assert_file "deep-hyphenated-name/app/assets/stylesheets/deep/hyphenated/name"
     assert_file "deep-hyphenated-name/app/assets/images/deep/hyphenated/name"
-    assert_file "deep-hyphenated-name/config/routes.rb",                                               /Deep::Hyphenated::Name::Engine.routes.draw do/
-    assert_file "deep-hyphenated-name/lib/deep/hyphenated/name/version.rb",                            /module Deep\n  module Hyphenated\n    module Name\n      VERSION = '0.1.0'\n    end\n  end\nend/
+    assert_file "deep-hyphenated-name/config/routes.rb",                                               /Deep::Hyphenated::Name::Engine\.routes\.draw do/
+    assert_file "deep-hyphenated-name/lib/deep/hyphenated/name/version.rb",                            /module Deep\n  module Hyphenated\n    module Name\n      VERSION = '0\.1\.0'\n    end\n  end\nend/
     assert_file "deep-hyphenated-name/lib/deep/hyphenated/name/engine.rb",                             /module Deep\n  module Hyphenated\n    module Name\n      class Engine < ::Rails::Engine\n        isolate_namespace Deep::Hyphenated::Name\n      end\n    end\n  end\nend/
     assert_file "deep-hyphenated-name/lib/deep/hyphenated/name.rb",                                    /require "deep\/hyphenated\/name\/engine"/
     assert_file "deep-hyphenated-name/test/dummy/config/routes.rb",                                    /mount Deep::Hyphenated::Name::Engine => "\/deep-hyphenated-name"/
     assert_file "deep-hyphenated-name/app/controllers/deep/hyphenated/name/application_controller.rb", /module Deep\n  module Hyphenated\n    module Name\n      class ApplicationController < ActionController::Base\n        protect_from_forgery with: :exception\n      end\n    end\n  end\nend\n/
     assert_file "deep-hyphenated-name/app/models/deep/hyphenated/name/application_record.rb",          /module Deep\n  module Hyphenated\n    module Name\n      class ApplicationRecord < ActiveRecord::Base\n        self\.abstract_class = true\n      end\n    end\n  end\nend/
     assert_file "deep-hyphenated-name/app/jobs/deep/hyphenated/name/application_job.rb",               /module Deep\n  module Hyphenated\n    module Name\n      class ApplicationJob < ActiveJob::Base/
-    assert_file "deep-hyphenated-name/app/mailers/deep/hyphenated/name/application_mailer.rb",         /module Deep\n  module Hyphenated\n    module Name\n      class ApplicationMailer < ActionMailer::Base\n        default from: 'from@example.com'\n        layout 'mailer'\n      end\n    end\n  end\nend/
+    assert_file "deep-hyphenated-name/app/mailers/deep/hyphenated/name/application_mailer.rb",         /module Deep\n  module Hyphenated\n    module Name\n      class ApplicationMailer < ActionMailer::Base\n        default from: 'from@example\.com'\n        layout 'mailer'\n      end\n    end\n  end\nend/
     assert_file "deep-hyphenated-name/app/helpers/deep/hyphenated/name/application_helper.rb",         /module Deep\n  module Hyphenated\n    module Name\n      module ApplicationHelper\n      end\n    end\n  end\nend/
     assert_file "deep-hyphenated-name/app/views/layouts/deep/hyphenated/name/application.html.erb" do |contents|
       assert_match "<title>Deep hyphenated name</title>", contents
@@ -393,15 +400,16 @@ class PluginGeneratorTest < Rails::Generators::TestCase
 
   def test_creating_gemspec
     run_generator
-    assert_file "bukkits.gemspec", /s.name\s+= "bukkits"/
-    assert_file "bukkits.gemspec", /s.files = Dir\["\{app,config,db,lib\}\/\*\*\/\*", "MIT-LICENSE", "Rakefile", "README\.md"\]/
-    assert_file "bukkits.gemspec", /s.version\s+ = Bukkits::VERSION/
+    assert_file "bukkits.gemspec", /s\.name\s+= "bukkits"/
+    assert_file "bukkits.gemspec", /s\.files = Dir\["\{app,config,db,lib\}\/\*\*\/\*", "MIT-LICENSE", "Rakefile", "README\.md"\]/
+    assert_file "bukkits.gemspec", /s\.version\s+ = Bukkits::VERSION/
   end
 
   def test_usage_of_engine_commands
     run_generator [destination_root, "--full"]
-    assert_file "bin/rails", /ENGINE_PATH = File.expand_path\('..\/..\/lib\/bukkits\/engine', __FILE__\)/
-    assert_file "bin/rails", /ENGINE_ROOT = File.expand_path\('..\/..', __FILE__\)/
+    assert_file "bin/rails", /ENGINE_PATH = File\.expand_path\('\.\.\/lib\/bukkits\/engine', __dir__\)/
+    assert_file "bin/rails", /ENGINE_ROOT = File\.expand_path\('\.\.', __dir__\)/
+    assert_file "bin/rails", %r|APP_PATH = File\.expand_path\('\.\./test/dummy/config/application', __dir__\)|
     assert_file "bin/rails", /require 'rails\/all'/
     assert_file "bin/rails", /require 'rails\/engine\/commands'/
   end
@@ -417,7 +425,7 @@ class PluginGeneratorTest < Rails::Generators::TestCase
     assert_file "spec/dummy/config/application.rb"
     assert_no_file "test/dummy"
     assert_file "test/test_helper.rb" do |content|
-      assert_match(/require.+spec\/dummy\/config\/environment/, content)
+      assert_match(/require_relative.+spec\/dummy\/config\/environment/, content)
       assert_match(/ActiveRecord::Migrator\.migrations_paths.+spec\/dummy\/db\/migrate/, content)
     end
   end
@@ -428,18 +436,17 @@ class PluginGeneratorTest < Rails::Generators::TestCase
     assert_file "spec/fake/config/application.rb"
     assert_no_file "test/dummy"
     assert_file "test/test_helper.rb" do |content|
-      assert_match(/require.+spec\/fake\/config\/environment/, content)
+      assert_match(/require_relative.+spec\/fake\/config\/environment/, content)
       assert_match(/ActiveRecord::Migrator\.migrations_paths.+spec\/fake\/db\/migrate/, content)
     end
   end
 
   def test_creating_dummy_without_tests_but_with_dummy_path
     run_generator [destination_root, "--dummy_path", "spec/dummy", "--skip-test"]
-    assert_file "spec/dummy"
-    assert_file "spec/dummy/config/application.rb"
-    assert_no_file "test"
-    assert_no_file "test/test_helper.rb"
-    assert_file '.gitignore' do |contents|
+    assert_directory "spec/dummy"
+    assert_file "spec/dummy/config/application.rb", /#\s+require\s+["']rails\/test_unit\/railtie["']/
+    assert_no_directory "test"
+    assert_file ".gitignore" do |contents|
       assert_match(/spec\/dummy/, contents)
     end
   end
@@ -447,8 +454,8 @@ class PluginGeneratorTest < Rails::Generators::TestCase
   def test_dummy_appplication_skip_listen_by_default
     run_generator
 
-    assert_file 'test/dummy/config/environments/development.rb' do |contents|
-      assert_match(/^\s*# config.file_watcher = ActiveSupport::EventedFileUpdateChecker/, contents)
+    assert_file "test/dummy/config/environments/development.rb" do |contents|
+      assert_match(/^\s*# config\.file_watcher = ActiveSupport::EventedFileUpdateChecker/, contents)
     end
   end
 
@@ -462,22 +469,24 @@ class PluginGeneratorTest < Rails::Generators::TestCase
 
   def test_unnecessary_files_are_not_generated_in_dummy_application
     run_generator
-    assert_no_file 'test/dummy/.gitignore'
-    assert_no_file 'test/dummy/db/seeds.rb'
-    assert_no_file 'test/dummy/Gemfile'
-    assert_no_file 'test/dummy/public/robots.txt'
-    assert_no_file 'test/dummy/README.md'
-    assert_no_directory 'test/dummy/lib/tasks'
-    assert_no_directory 'test/dummy/doc'
-    assert_no_directory 'test/dummy/test'
-    assert_no_directory 'test/dummy/vendor'
+    assert_no_file "test/dummy/.gitignore"
+    assert_no_file "test/dummy/db/seeds.rb"
+    assert_no_file "test/dummy/Gemfile"
+    assert_no_file "test/dummy/public/robots.txt"
+    assert_no_file "test/dummy/README.md"
+    assert_no_file "test/dummy/config/master.key"
+    assert_no_file "test/dummy/config/credentials.yml.enc"
+    assert_no_directory "test/dummy/lib/tasks"
+    assert_no_directory "test/dummy/test"
+    assert_no_directory "test/dummy/vendor"
+    assert_no_directory "test/dummy/.git"
   end
 
   def test_skipping_test_files
     run_generator [destination_root, "--skip-test"]
-    assert_no_file "test"
-    assert_file '.gitignore' do |contents|
-      assert_no_match(/test\dummy/, contents)
+    assert_no_directory "test"
+    assert_file ".gitignore" do |contents|
+      assert_no_match(/test\/dummy/, contents)
     end
   end
 
@@ -485,10 +494,9 @@ class PluginGeneratorTest < Rails::Generators::TestCase
     run_generator [destination_root, "--skip-gemspec"]
     assert_no_file "bukkits.gemspec"
     assert_file "Gemfile" do |contents|
-      assert_no_match('gemspec', contents)
+      assert_no_match("gemspec", contents)
       assert_match(/gem 'rails'/, contents)
       assert_match_sqlite3(contents)
-      assert_no_match(/# gem "jquery-rails"/, contents)
     end
   end
 
@@ -496,7 +504,7 @@ class PluginGeneratorTest < Rails::Generators::TestCase
     run_generator [destination_root, "--skip-gemspec", "--full"]
     assert_no_file "bukkits.gemspec"
     assert_file "Gemfile" do |contents|
-      assert_no_match('gemspec', contents)
+      assert_no_match("gemspec", contents)
       assert_match(/gem 'rails'/, contents)
       assert_match_sqlite3(contents)
     end
@@ -505,21 +513,37 @@ class PluginGeneratorTest < Rails::Generators::TestCase
   def test_creating_plugin_in_app_directory_adds_gemfile_entry
     # simulate application existence
     gemfile_path = "#{Rails.root}/Gemfile"
-    Object.const_set('APP_PATH', Rails.root)
+    Object.const_set("APP_PATH", Rails.root)
     FileUtils.touch gemfile_path
+    File.write(gemfile_path, "#foo")
 
     run_generator
 
-    assert_file gemfile_path, /gem 'bukkits', path: 'tmp\/bukkits'/
+    assert_file gemfile_path, /^gem 'bukkits', path: 'tmp\/bukkits'/
   ensure
-    Object.send(:remove_const, 'APP_PATH')
+    Object.send(:remove_const, "APP_PATH")
+    FileUtils.rm gemfile_path
+  end
+
+  def test_creating_plugin_only_specify_plugin_name_in_app_directory_adds_gemfile_entry
+    # simulate application existence
+    gemfile_path = "#{Rails.root}/Gemfile"
+    Object.const_set("APP_PATH", Rails.root)
+    FileUtils.touch gemfile_path
+
+    FileUtils.cd(destination_root)
+    run_generator ["bukkits"]
+
+    assert_file gemfile_path, /gem 'bukkits', path: 'bukkits'/
+  ensure
+    Object.send(:remove_const, "APP_PATH")
     FileUtils.rm gemfile_path
   end
 
   def test_skipping_gemfile_entry
     # simulate application existence
     gemfile_path = "#{Rails.root}/Gemfile"
-    Object.const_set('APP_PATH', Rails.root)
+    Object.const_set("APP_PATH", Rails.root)
     FileUtils.touch gemfile_path
 
     run_generator [destination_root, "--skip-gemfile-entry"]
@@ -528,7 +552,7 @@ class PluginGeneratorTest < Rails::Generators::TestCase
       assert_no_match(/gem 'bukkits', path: 'tmp\/bukkits'/, contents)
     end
   ensure
-    Object.send(:remove_const, 'APP_PATH')
+    Object.send(:remove_const, "APP_PATH")
     FileUtils.rm gemfile_path
   end
 
@@ -569,7 +593,7 @@ class PluginGeneratorTest < Rails::Generators::TestCase
     name = "TODO: Write your name"
     email = "TODO: Write your email address"
 
-    run_generator [destination_root, '--skip-git']
+    run_generator [destination_root, "--skip-git"]
     assert_file "MIT-LICENSE" do |contents|
       assert_match name, contents
     end
@@ -580,8 +604,8 @@ class PluginGeneratorTest < Rails::Generators::TestCase
   end
 
   def test_skipping_useless_folders_generation_for_api_engines
-    ['--full', '--mountable'].each do |option|
-      run_generator [destination_root, option, '--api']
+    ["--full", "--mountable"].each do |option|
+      run_generator [destination_root, option, "--api"]
 
       assert_no_directory "app/assets"
       assert_no_directory "app/helpers"
@@ -592,7 +616,7 @@ class PluginGeneratorTest < Rails::Generators::TestCase
   end
 
   def test_application_controller_parent_for_mountable_api_plugins
-    run_generator [destination_root, '--mountable', '--api']
+    run_generator [destination_root, "--mountable", "--api"]
 
     assert_file "app/controllers/bukkits/application_controller.rb" do |content|
       assert_match "ApplicationController < ActionController::API", content
@@ -600,16 +624,15 @@ class PluginGeneratorTest < Rails::Generators::TestCase
   end
 
   def test_dummy_api_application_for_api_plugins
-    run_generator [destination_root, '--api']
+    run_generator [destination_root, "--api"]
 
     assert_file "test/dummy/config/application.rb" do |content|
       assert_match "config.api_only = true", content
     end
   end
 
-
   def test_api_generators_configuration_for_api_engines
-    run_generator [destination_root, '--full', '--api']
+    run_generator [destination_root, "--full", "--api"]
 
     assert_file "lib/bukkits/engine.rb" do |content|
       assert_match "config.generators.api_only = true", content
@@ -617,7 +640,7 @@ class PluginGeneratorTest < Rails::Generators::TestCase
   end
 
   def test_scaffold_generator_for_mountable_api_plugins
-    run_generator [destination_root, '--mountable', '--api']
+    run_generator [destination_root, "--mountable", "--api"]
 
     capture(:stdout) do
       `#{destination_root}/bin/rails g scaffold article`
@@ -634,7 +657,7 @@ class PluginGeneratorTest < Rails::Generators::TestCase
   end
 
   def test_model_with_existent_application_record_in_mountable_engine
-    run_generator [destination_root, '--mountable']
+    run_generator [destination_root, "--mountable"]
     capture(:stdout) do
       `#{destination_root}/bin/rails g model article`
     end
@@ -642,22 +665,8 @@ class PluginGeneratorTest < Rails::Generators::TestCase
     assert_file "app/models/bukkits/article.rb", /class Article < ApplicationRecord/
   end
 
-  def test_generate_application_record_when_does_not_exist_in_mountable_engine
-    run_generator [destination_root, '--mountable']
-    FileUtils.rm "#{destination_root}/app/models/bukkits/application_record.rb"
-    capture(:stdout) do
-      `#{destination_root}/bin/rails g model article`
-    end
-
-    assert_file "#{destination_root}/app/models/bukkits/application_record.rb" do |record|
-      assert_match(/module Bukkits/, record)
-      assert_match(/class ApplicationRecord < ActiveRecord::Base/, record)
-      assert_match(/self.abstract_class = true/, record)
-    end
-  end
-
   def test_generate_application_mailer_when_does_not_exist_in_mountable_engine
-    run_generator [destination_root, '--mountable']
+    run_generator [destination_root, "--mountable"]
     FileUtils.rm "#{destination_root}/app/mailers/bukkits/application_mailer.rb"
     capture(:stdout) do
       `#{destination_root}/bin/rails g mailer User`
@@ -670,7 +679,7 @@ class PluginGeneratorTest < Rails::Generators::TestCase
   end
 
   def test_generate_mailer_layouts_when_does_not_exist_in_mountable_engine
-    run_generator [destination_root, '--mountable']
+    run_generator [destination_root, "--mountable"]
     capture(:stdout) do
       `#{destination_root}/bin/rails g mailer User`
     end
@@ -685,7 +694,7 @@ class PluginGeneratorTest < Rails::Generators::TestCase
   end
 
   def test_generate_application_job_when_does_not_exist_in_mountable_engine
-    run_generator [destination_root, '--mountable']
+    run_generator [destination_root, "--mountable"]
     FileUtils.rm "#{destination_root}/app/jobs/bukkits/application_job.rb"
     capture(:stdout) do
       `#{destination_root}/bin/rails g job refresh_counters`
@@ -697,48 +706,85 @@ class PluginGeneratorTest < Rails::Generators::TestCase
     end
   end
 
+  def test_app_update_generates_bin_file
+    run_generator [destination_root, "--mountable"]
+
+    Object.const_set("ENGINE_ROOT", destination_root)
+    FileUtils.rm("#{destination_root}/bin/rails")
+
+    quietly { Rails::Engine::Updater.run(:create_bin_files) }
+
+    assert_file "#{destination_root}/bin/rails" do |content|
+      assert_match(%r|APP_PATH = File\.expand_path\('\.\./test/dummy/config/application', __dir__\)|, content)
+    end
+  ensure
+    Object.send(:remove_const, "ENGINE_ROOT")
+  end
+
   def test_after_bundle_callback
-    path = 'http://example.org/rails_template'
-    template = %{ after_bundle { run 'echo ran after_bundle' } }
+    path = "http://example.org/rails_template"
+    template = %{ after_bundle { run "echo ran after_bundle" } }.dup
     template.instance_eval "def read; self; end" # Make the string respond to read
 
     check_open = -> *args do
-      assert_equal [ path, 'Accept' => 'application/x-thor-template' ], args
+      assert_equal [ path, "Accept" => "application/x-thor-template" ], args
       template
     end
 
-    sequence = ['install', 'echo ran after_bundle']
+    sequence = ["echo ran after_bundle"]
     @sequence_step ||= 0
     ensure_bundler_first = -> command do
       assert_equal sequence[@sequence_step], command, "commands should be called in sequence #{sequence}"
       @sequence_step += 1
     end
 
+    content = nil
     generator([destination_root], template: path).stub(:open, check_open, template) do
       generator.stub(:bundle_command, ensure_bundler_first) do
         generator.stub(:run, ensure_bundler_first) do
-          quietly { generator.invoke_all }
+          silence_stream($stdout) do
+            content = capture(:stderr) { generator.invoke_all }
+          end
         end
       end
     end
 
-    assert_equal 2, @sequence_step
+    assert_equal 1, @sequence_step
+    assert_match(/DEPRECATION WARNING: `after_bundle` is deprecated/, content)
   end
 
-protected
-  def action(*args, &block)
-    silence(:stdout){ generator.send(*args, &block) }
-  end
+  private
 
-  def default_files
-    ::DEFAULT_PLUGIN_FILES
-  end
+    def action(*args, &block)
+      silence(:stdout) { generator.send(*args, &block) }
+    end
 
-  def assert_match_sqlite3(contents)
-    if defined?(JRUBY_VERSION)
-      assert_match(/group :development do\n  gem 'activerecord-jdbcsqlite3-adapter'\nend/, contents)
-    else
-      assert_match(/group :development do\n  gem 'sqlite3'\nend/, contents)
+    def default_files
+      ::DEFAULT_PLUGIN_FILES
+    end
+
+    def assert_match_sqlite3(contents)
+      if defined?(JRUBY_VERSION)
+        assert_match(/group :development do\n  gem 'activerecord-jdbcsqlite3-adapter'\nend/, contents)
+      else
+        assert_match(/group :development do\n  gem 'sqlite3'\nend/, contents)
+      end
+    end
+
+    def assert_generates_without_bundler(options = {})
+      generator([destination_root], options)
+
+      command_check = -> command do
+        case command
+        when "install"
+          flunk "install expected to not be called"
+        when "exec spring binstub --all"
+          # Called when running tests with spring, let through unscathed.
+        end
+      end
+
+      generator.stub :bundle_command, command_check do
+        quietly { generator.invoke_all }
+      end
     end
-  end
 end
diff --git a/railties/test/generators/plugin_test_helper.rb b/railties/test/generators/plugin_test_helper.rb
index 96c1b1d31f..528f8d88f9 100644
--- a/railties/test/generators/plugin_test_helper.rb
+++ b/railties/test/generators/plugin_test_helper.rb
@@ -1,5 +1,7 @@
-require 'abstract_unit'
-require 'tmpdir'
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "tmpdir"
 
 module PluginTestHelper
   def create_test_file(name, pass: true)
@@ -15,7 +17,7 @@ module PluginTestHelper
     RUBY
   end
 
-  def plugin_file(path, contents, mode: 'w')
+  def plugin_file(path, contents, mode: "w")
     FileUtils.mkdir_p File.dirname("#{plugin_path}/#{path}")
     File.open("#{plugin_path}/#{path}", mode) do |f|
       f.puts contents
diff --git a/railties/test/generators/plugin_test_runner_test.rb b/railties/test/generators/plugin_test_runner_test.rb
index ef6359fece..89c3f1e496 100644
--- a/railties/test/generators/plugin_test_runner_test.rb
+++ b/railties/test/generators/plugin_test_runner_test.rb
@@ -1,12 +1,14 @@
-require 'generators/plugin_test_helper'
+# frozen_string_literal: true
+
+require "generators/plugin_test_helper"
 
 class PluginTestRunnerTest < ActiveSupport::TestCase
   include PluginTestHelper
 
   def setup
-    @destination_root = Dir.mktmpdir('bukkits')
+    @destination_root = Dir.mktmpdir("bukkits")
     Dir.chdir(@destination_root) { `bundle exec rails plugin new bukkits --skip-bundle` }
-    plugin_file 'test/dummy/db/schema.rb', ''
+    plugin_file "test/dummy/db/schema.rb", ""
   end
 
   def teardown
@@ -14,20 +16,20 @@ class PluginTestRunnerTest < ActiveSupport::TestCase
   end
 
   def test_run_single_file
-    create_test_file 'foo'
-    create_test_file 'bar'
+    create_test_file "foo"
+    create_test_file "bar"
     assert_match "1 runs, 1 assertions, 0 failures", run_test_command("test/foo_test.rb")
   end
 
   def test_run_multiple_files
-    create_test_file 'foo'
-    create_test_file 'bar'
+    create_test_file "foo"
+    create_test_file "bar"
     assert_match "2 runs, 2 assertions, 0 failures", run_test_command("test/foo_test.rb test/bar_test.rb")
   end
 
   def test_mix_files_and_line_filters
-    create_test_file 'account'
-    plugin_file 'test/post_test.rb', <<-RUBY
+    create_test_file "account"
+    plugin_file "test/post_test.rb", <<-RUBY
       require 'test_helper'
 
       class PostTest < ActiveSupport::TestCase
@@ -42,50 +44,73 @@ class PluginTestRunnerTest < ActiveSupport::TestCase
       end
     RUBY
 
-    run_test_command('test/account_test.rb test/post_test.rb:4').tap do |output|
-      assert_match 'AccountTest', output
-      assert_match 'PostTest', output
-      assert_match '2 runs, 2 assertions', output
+    run_test_command("test/account_test.rb test/post_test.rb:4").tap do |output|
+      assert_match "AccountTest", output
+      assert_match "PostTest", output
+      assert_match "2 runs, 2 assertions", output
     end
   end
 
   def test_multiple_line_filters
-    create_test_file 'account'
-    create_test_file 'post'
+    create_test_file "account"
+    create_test_file "post"
 
-    run_test_command('test/account_test.rb:4 test/post_test.rb:4').tap do |output|
-      assert_match 'AccountTest', output
-      assert_match 'PostTest', output
+    run_test_command("test/account_test.rb:4 test/post_test.rb:4").tap do |output|
+      assert_match "AccountTest", output
+      assert_match "PostTest", output
     end
   end
 
   def test_output_inline_by_default
-    create_test_file 'post', pass: false
+    create_test_file "post", pass: false
 
-    output = run_test_command('test/post_test.rb')
+    output = run_test_command("test/post_test.rb")
     expect = %r{Running:\n\nPostTest\nF\n\nFailure:\nPostTest#test_truth \[[^\]]+test/post_test.rb:6\]:\nwups!\n\nbin/test (/private)?#{plugin_path}/test/post_test.rb:4}
     assert_match expect, output
   end
 
   def test_only_inline_failure_output
-    create_test_file 'post', pass: false
+    create_test_file "post", pass: false
 
-    output = run_test_command('test/post_test.rb')
-    assert_match %r{Finished in.*\n\n1 runs, 1 assertions}, output
+    output = run_test_command("test/post_test.rb")
+    assert_match %r{Finished in.*\n1 runs, 1 assertions}, output
   end
 
   def test_fail_fast
-    create_test_file 'post', pass: false
+    create_test_file "post", pass: false
 
     assert_match(/Interrupt/,
-      capture(:stderr) { run_test_command('test/post_test.rb --fail-fast') })
+      capture(:stderr) { run_test_command("test/post_test.rb --fail-fast") })
   end
 
   def test_raise_error_when_specified_file_does_not_exist
-    error = capture(:stderr) { run_test_command('test/not_exists.rb') }
+    error = capture(:stderr) { run_test_command("test/not_exists.rb") }
     assert_match(%r{cannot load such file.+test/not_exists\.rb}, error)
   end
 
+  def test_executed_only_once
+    create_test_file "foo"
+    result = run_test_command("test/foo_test.rb")
+    assert_equal 1, result.scan(/1 runs, 1 assertions, 0 failures/).length
+  end
+
+  def test_warnings_option
+    plugin_file "test/models/warnings_test.rb", <<-RUBY
+      require 'test_helper'
+      def test_warnings
+        a = 1
+      end
+    RUBY
+    assert_match(/warning: assigned but unused variable/,
+      capture(:stderr) { run_test_command("test/models/warnings_test.rb -w") })
+  end
+
+  def test_run_rake_test
+    create_test_file "foo"
+    result = Dir.chdir(plugin_path) { `rake test TEST=test/foo_test.rb` }
+    assert_match "1 runs, 1 assertions, 0 failures", result
+  end
+
   private
     def plugin_path
       "#{@destination_root}/bukkits"
diff --git a/railties/test/generators/resource_generator_test.rb b/railties/test/generators/resource_generator_test.rb
index 53dcfc4024..63a2cd3869 100644
--- a/railties/test/generators/resource_generator_test.rb
+++ b/railties/test/generators/resource_generator_test.rb
@@ -1,5 +1,7 @@
-require 'generators/generators_test_helper'
-require 'rails/generators/rails/resource/resource_generator'
+# frozen_string_literal: true
+
+require "generators/generators_test_helper"
+require "rails/generators/rails/resource/resource_generator"
 
 class ResourceGeneratorTest < Rails::Generators::TestCase
   include GeneratorsTestHelper
diff --git a/railties/test/generators/scaffold_controller_generator_test.rb b/railties/test/generators/scaffold_controller_generator_test.rb
index 736ff0b41f..fd5aa817b4 100644
--- a/railties/test/generators/scaffold_controller_generator_test.rb
+++ b/railties/test/generators/scaffold_controller_generator_test.rb
@@ -1,5 +1,7 @@
-require 'generators/generators_test_helper'
-require 'rails/generators/rails/scaffold_controller/scaffold_controller_generator'
+# frozen_string_literal: true
+
+require "generators/generators_test_helper"
+require "rails/generators/rails/scaffold_controller/scaffold_controller_generator"
 
 module Unknown
   module Generators
@@ -172,6 +174,29 @@ class ScaffoldControllerGeneratorTest < Rails::Generators::TestCase
       assert_instance_method :index, content do |m|
         assert_match("@users = User.all", m)
       end
+
+      assert_instance_method :create, content do |m|
+        assert_match("redirect_to [:admin, @user]", m)
+      end
+
+      assert_instance_method :update, content do |m|
+        assert_match("redirect_to [:admin, @user]", m)
+      end
+    end
+
+    assert_file "app/views/admin/users/index.html.erb" do |content|
+      assert_match("'Show', [:admin, user]", content)
+      assert_match("'Edit', edit_admin_user_path(user)", content)
+      assert_match("'Destroy', [:admin, user]", content)
+      assert_match("'New User', new_admin_user_path", content)
+    end
+
+    assert_file "app/views/admin/users/new.html.erb" do |content|
+      assert_match("'Back', admin_users_path", content)
+    end
+
+    assert_file "app/views/admin/users/_form.html.erb" do |content|
+      assert_match("model: [:admin, user]", content)
     end
   end
 
@@ -182,6 +207,7 @@ class ScaffoldControllerGeneratorTest < Rails::Generators::TestCase
 
     Dir.chdir(engine_path) do
       quietly { `bin/rails g controller dashboard foo` }
+      quietly { `bin/rails db:migrate RAILS_ENV=test` }
       assert_match(/2 runs, 2 assertions, 0 failures, 0 errors/, `bin/rails test 2>&1`)
     end
   end
@@ -193,6 +219,7 @@ class ScaffoldControllerGeneratorTest < Rails::Generators::TestCase
 
     Dir.chdir(engine_path) do
       quietly { `bin/rails g controller dashboard foo` }
+      quietly { `bin/rails db:migrate RAILS_ENV=test` }
       assert_match(/2 runs, 2 assertions, 0 failures, 0 errors/, `bin/rails test 2>&1`)
     end
   end
@@ -230,6 +257,12 @@ class ScaffoldControllerGeneratorTest < Rails::Generators::TestCase
         assert_match(/@user\.destroy/, m)
       end
     end
+
+    assert_no_file "app/views/users/index.html.erb"
+    assert_no_file "app/views/users/edit.html.erb"
+    assert_no_file "app/views/users/show.html.erb"
+    assert_no_file "app/views/users/new.html.erb"
+    assert_no_file "app/views/users/_form.html.erb"
   end
 
   def test_api_controller_tests
diff --git a/railties/test/generators/scaffold_generator_test.rb b/railties/test/generators/scaffold_generator_test.rb
index bd69906b9d..29426cd99f 100644
--- a/railties/test/generators/scaffold_generator_test.rb
+++ b/railties/test/generators/scaffold_generator_test.rb
@@ -1,5 +1,7 @@
-require 'generators/generators_test_helper'
-require 'rails/generators/rails/scaffold/scaffold_generator'
+# frozen_string_literal: true
+
+require "generators/generators_test_helper"
+require "rails/generators/rails/scaffold/scaffold_generator"
 
 class ScaffoldGeneratorTest < Rails::Generators::TestCase
   include GeneratorsTestHelper
@@ -62,6 +64,14 @@ class ScaffoldGeneratorTest < Rails::Generators::TestCase
       assert_match(/patch product_line_url\(@product_line\), params: \{ product_line: \{ product_id: @product_line\.product_id, title: @product_line\.title, user_id: @product_line\.user_id \} \}/, test)
     end
 
+    # System tests
+    assert_file "test/system/product_lines_test.rb" do |test|
+      assert_match(/class ProductLinesTest < ApplicationSystemTestCase/, test)
+      assert_match(/visit product_lines_url/, test)
+      assert_match(/fill_in "Title", with: @product_line\.title/, test)
+      assert_match(/assert_text "Product line was successfully updated"/, test)
+    end
+
     # Views
     assert_no_file "app/views/layouts/product_lines.html.erb"
 
@@ -74,8 +84,8 @@ class ScaffoldGeneratorTest < Rails::Generators::TestCase
     end
 
     assert_file "app/views/product_lines/_form.html.erb" do |test|
-      assert_match 'product_line', test
-      assert_no_match '@product_line', test
+      assert_match "product_line", test
+      assert_no_match "@product_line", test
     end
 
     # Helpers
@@ -141,6 +151,9 @@ class ScaffoldGeneratorTest < Rails::Generators::TestCase
       assert_no_match(/assert_redirected_to/, test)
     end
 
+    # System tests
+    assert_no_file "test/system/product_lines_test.rb"
+
     # Views
     assert_no_file "app/views/layouts/product_lines.html.erb"
 
@@ -168,6 +181,16 @@ class ScaffoldGeneratorTest < Rails::Generators::TestCase
     end
   end
 
+  def test_system_tests_without_attributes
+    run_generator ["product_line"]
+
+    assert_file "test/system/product_lines_test.rb" do |content|
+      assert_match(/class ProductLinesTest < ApplicationSystemTestCase/, content)
+      assert_match(/test "visiting the index"/, content)
+      assert_no_match(/fill_in/, content)
+    end
+  end
+
   def test_scaffold_on_revoke
     run_generator
     run_generator ["product_line"], behavior: :revoke
@@ -187,6 +210,9 @@ class ScaffoldGeneratorTest < Rails::Generators::TestCase
     assert_no_file "app/controllers/product_lines_controller.rb"
     assert_no_file "test/controllers/product_lines_controller_test.rb"
 
+    # System tests
+    assert_no_file "test/system/product_lines_test.rb"
+
     # Views
     assert_no_file "app/views/product_lines"
     assert_no_file "app/views/layouts/product_lines.html.erb"
@@ -252,8 +278,18 @@ class ScaffoldGeneratorTest < Rails::Generators::TestCase
     assert_file "test/controllers/admin/roles_controller_test.rb",
                 /class Admin::RolesControllerTest < ActionDispatch::IntegrationTest/
 
+    assert_file "test/system/admin/roles_test.rb",
+                /class Admin::RolesTest < ApplicationSystemTestCase/
+
     # Views
-    %w(index edit new show _form).each do |view|
+    assert_file "app/views/admin/roles/index.html.erb" do |content|
+      assert_match("'Show', admin_role", content)
+      assert_match("'Edit', edit_admin_role_path(admin_role)", content)
+      assert_match("'Destroy', admin_role", content)
+      assert_match("'New Admin Role', new_admin_role_path", content)
+    end
+
+    %w(edit new show _form).each do |view|
       assert_file "app/views/admin/roles/#{view}.html.erb"
     end
     assert_no_file "app/views/layouts/admin/roles.html.erb"
@@ -269,7 +305,7 @@ class ScaffoldGeneratorTest < Rails::Generators::TestCase
 
   def test_scaffold_with_namespace_on_revoke
     run_generator [ "admin/role", "name:string", "description:string" ]
-    run_generator [ "admin/role" ], :behavior => :revoke
+    run_generator [ "admin/role" ], behavior: :revoke
 
     # Model
     assert_file "app/models/admin.rb" # ( should not be remove )
@@ -287,6 +323,9 @@ class ScaffoldGeneratorTest < Rails::Generators::TestCase
     assert_no_file "app/controllers/admin/roles_controller.rb"
     assert_no_file "test/controllers/admin/roles_controller_test.rb"
 
+    # System tests
+    assert_no_file "test/system/admin/roles_test.rb"
+
     # Views
     assert_no_file "app/views/admin/roles"
     assert_no_file "app/views/layouts/admin/roles.html.erb"
@@ -310,7 +349,7 @@ class ScaffoldGeneratorTest < Rails::Generators::TestCase
     end
     File.open(route_path, "wb") { |file| file.write(content) }
 
-    run_generator ["product_line"], :behavior => :revoke
+    run_generator ["product_line"], behavior: :revoke
 
     assert_file "config/routes.rb", /\.routes\.draw do\s*\|map\|\s*$/
   end
@@ -322,13 +361,13 @@ class ScaffoldGeneratorTest < Rails::Generators::TestCase
     content = File.read(route_path)
 
     # Remove all of the comments and blank lines from the routes file
-    content.gsub!(/^  \#.*\n/, '')
-    content.gsub!(/^\n/, '')
+    content.gsub!(/^  \#.*\n/, "")
+    content.gsub!(/^\n/, "")
 
     File.open(route_path, "wb") { |file| file.write(content) }
     assert_file "config/routes.rb", /\.routes\.draw do\n  resources :product_lines\nend\n\z/
 
-    run_generator ["product_line"], :behavior => :revoke
+    run_generator ["product_line"], behavior: :revoke
 
     assert_file "config/routes.rb", /\.routes\.draw do\nend\n\z/
   end
@@ -432,8 +471,8 @@ class ScaffoldGeneratorTest < Rails::Generators::TestCase
     end
 
     assert_file "app/views/accounts/_form.html.erb" do |content|
-      assert_match(/^\W{4}<%= f\.text_field :name %>/, content)
-      assert_match(/^\W{4}<%= f\.text_field :currency_id %>/, content)
+      assert_match(/^\W{4}<%= form\.text_field :name %>/, content)
+      assert_match(/^\W{4}<%= form\.text_field :currency_id %>/, content)
     end
   end
 
@@ -456,8 +495,8 @@ class ScaffoldGeneratorTest < Rails::Generators::TestCase
     end
 
     assert_file "app/views/users/_form.html.erb" do |content|
-      assert_match(/<%= f\.password_field :password %>/, content)
-      assert_match(/<%= f\.password_field :password_confirmation %>/, content)
+      assert_match(/<%= form\.password_field :password %>/, content)
+      assert_match(/<%= form\.password_field :password_confirmation %>/, content)
     end
 
     assert_file "app/views/users/index.html.erb" do |content|
@@ -473,6 +512,11 @@ class ScaffoldGeneratorTest < Rails::Generators::TestCase
       assert_match(/password_confirmation: 'secret'/, content)
     end
 
+    assert_file "test/system/users_test.rb" do |content|
+      assert_match(/fill_in "Password", with: 'secret'/, content)
+      assert_match(/fill_in "Password Confirmation", with: 'secret'/, content)
+    end
+
     assert_file "test/fixtures/users.yml" do |content|
       assert_match(/password_digest: <%= BCrypt::Password.create\('secret'\) %>/, content)
     end
@@ -492,6 +536,26 @@ class ScaffoldGeneratorTest < Rails::Generators::TestCase
     end
   end
 
+  def test_scaffold_tests_pass_by_default_inside_namespaced_mountable_engine
+    Dir.chdir(destination_root) { `bundle exec rails plugin new bukkits-admin --mountable` }
+
+    engine_path = File.join(destination_root, "bukkits-admin")
+
+    Dir.chdir(engine_path) do
+      quietly do
+        `bin/rails g scaffold User name:string age:integer;
+        bin/rails db:migrate`
+      end
+
+      assert_file "bukkits-admin/app/controllers/bukkits/admin/users_controller.rb" do |content|
+        assert_match(/module Bukkits::Admin/, content)
+        assert_match(/class UsersController < ApplicationController/, content)
+      end
+
+      assert_match(/8 runs, 10 assertions, 0 failures, 0 errors/, `bin/rails test 2>&1`)
+    end
+  end
+
   def test_scaffold_tests_pass_by_default_inside_full_engine
     Dir.chdir(destination_root) { `bundle exec rails plugin new bukkits --full` }
 
@@ -533,4 +597,63 @@ class ScaffoldGeneratorTest < Rails::Generators::TestCase
       assert_match(/6 runs, 8 assertions, 0 failures, 0 errors/, `bin/rails test 2>&1`)
     end
   end
+
+  def test_scaffold_on_invoke_inside_mountable_engine
+    Dir.chdir(destination_root) { `bundle exec rails plugin new bukkits --mountable` }
+    engine_path = File.join(destination_root, "bukkits")
+
+    Dir.chdir(engine_path) do
+      quietly { `bin/rails generate scaffold User name:string age:integer` }
+
+      assert File.exist?("app/models/bukkits/user.rb")
+      assert File.exist?("test/models/bukkits/user_test.rb")
+      assert File.exist?("test/fixtures/bukkits/users.yml")
+
+      assert File.exist?("app/controllers/bukkits/users_controller.rb")
+      assert File.exist?("test/controllers/bukkits/users_controller_test.rb")
+
+      assert File.exist?("test/system/bukkits/users_test.rb")
+
+      assert File.exist?("app/views/bukkits/users/index.html.erb")
+      assert File.exist?("app/views/bukkits/users/edit.html.erb")
+      assert File.exist?("app/views/bukkits/users/show.html.erb")
+      assert File.exist?("app/views/bukkits/users/new.html.erb")
+      assert File.exist?("app/views/bukkits/users/_form.html.erb")
+
+      assert File.exist?("app/helpers/bukkits/users_helper.rb")
+
+      assert File.exist?("app/assets/javascripts/bukkits/users.js")
+      assert File.exist?("app/assets/stylesheets/bukkits/users.css")
+    end
+  end
+
+  def test_scaffold_on_revoke_inside_mountable_engine
+    Dir.chdir(destination_root) { `bundle exec rails plugin new bukkits --mountable` }
+    engine_path = File.join(destination_root, "bukkits")
+
+    Dir.chdir(engine_path) do
+      quietly { `bin/rails generate scaffold User name:string age:integer` }
+      quietly { `bin/rails destroy scaffold User` }
+
+      assert_not File.exist?("app/models/bukkits/user.rb")
+      assert_not File.exist?("test/models/bukkits/user_test.rb")
+      assert_not File.exist?("test/fixtures/bukkits/users.yml")
+
+      assert_not File.exist?("app/controllers/bukkits/users_controller.rb")
+      assert_not File.exist?("test/controllers/bukkits/users_controller_test.rb")
+
+      assert_not File.exist?("test/system/bukkits/users_test.rb")
+
+      assert_not File.exist?("app/views/bukkits/users/index.html.erb")
+      assert_not File.exist?("app/views/bukkits/users/edit.html.erb")
+      assert_not File.exist?("app/views/bukkits/users/show.html.erb")
+      assert_not File.exist?("app/views/bukkits/users/new.html.erb")
+      assert_not File.exist?("app/views/bukkits/users/_form.html.erb")
+
+      assert_not File.exist?("app/helpers/bukkits/users_helper.rb")
+
+      assert_not File.exist?("app/assets/javascripts/bukkits/users.js")
+      assert_not File.exist?("app/assets/stylesheets/bukkits/users.css")
+    end
+  end
 end
diff --git a/railties/test/generators/shared_generator_tests.rb b/railties/test/generators/shared_generator_tests.rb
index e83d54890a..29528825b8 100644
--- a/railties/test/generators/shared_generator_tests.rb
+++ b/railties/test/generators/shared_generator_tests.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 #
 # Tests, setup, and teardown common to the application and plugin generator suites.
 #
@@ -5,7 +7,7 @@ module SharedGeneratorTests
   def setup
     Rails.application = TestApp::Application
     super
-    Rails::Generators::AppGenerator.instance_variable_set('@desc', nil)
+    Rails::Generators::AppGenerator.instance_variable_set("@desc", nil)
 
     Kernel::silence_warnings do
       Thor::Base.shell.send(:attr_accessor, :always_force)
@@ -16,47 +18,27 @@ module SharedGeneratorTests
 
   def teardown
     super
-    Rails::Generators::AppGenerator.instance_variable_set('@desc', nil)
+    Rails::Generators::AppGenerator.instance_variable_set("@desc", nil)
     Rails.application = TestApp::Application.instance
   end
 
+  def application_path
+    destination_root
+  end
+
   def test_skeleton_is_created
     run_generator
 
     default_files.each { |path| assert_file path }
   end
 
-  def assert_generates_with_bundler(options = {})
-    generator([destination_root], options)
-
-    command_check = -> command do
-      @install_called ||= 0
-
-      case command
-      when 'install'
-        @install_called += 1
-        assert_equal 1, @install_called, "install expected to be called once, but was called #{@install_called} times"
-      when 'exec spring binstub --all'
-        # Called when running tests with spring, let through unscathed.
-      end
-    end
-
-    generator.stub :bundle_command, command_check do
-      quietly { generator.invoke_all }
-    end
-  end
-
-  def test_generation_runs_bundle_install
-    assert_generates_with_bundler
-  end
-
   def test_plugin_new_generate_pretend
     run_generator ["testapp", "--pretend"]
-    default_files.each{ |path| assert_no_file File.join("testapp",path) }
+    default_files.each { |path| assert_no_file File.join("testapp", path) }
   end
 
   def test_invalid_database_option_raises_an_error
-    content = capture(:stderr){ run_generator([destination_root, "-d", "unknown"]) }
+    content = capture(:stderr) { run_generator([destination_root, "-d", "unknown"]) }
     assert_match(/Invalid value for \-\-database option/, content)
   end
 
@@ -68,15 +50,15 @@ module SharedGeneratorTests
   def test_name_collision_raises_an_error
     reserved_words = %w[application destroy plugin runner test]
     reserved_words.each do |reserved|
-      content = capture(:stderr){ run_generator [File.join(destination_root, reserved)] }
-      assert_match(/Invalid \w+ name #{reserved}. Please give a name which does not match one of the reserved rails words: application, destroy, plugin, runner, test\n/, content)
+      content = capture(:stderr) { run_generator [File.join(destination_root, reserved)] }
+      assert_match(/Invalid \w+ name #{reserved}\. Please give a name which does not match one of the reserved rails words: application, destroy, plugin, runner, test\n/, content)
     end
   end
 
   def test_name_raises_an_error_if_name_already_used_constant
     %w{ String Hash Class Module Set Symbol }.each do |ruby_class|
-      content = capture(:stderr){ run_generator [File.join(destination_root, ruby_class)] }
-      assert_match(/Invalid \w+ name #{ruby_class}, constant #{ruby_class} is already in use. Please choose another \w+ name.\n/, content)
+      content = capture(:stderr) { run_generator [File.join(destination_root, ruby_class)] }
+      assert_match(/Invalid \w+ name #{ruby_class}, constant #{ruby_class} is already in use\. Please choose another \w+ name\.\n/, content)
     end
   end
 
@@ -92,7 +74,7 @@ module SharedGeneratorTests
 
   def test_template_raises_an_error_with_invalid_path
     quietly do
-      content = capture(:stderr){ run_generator([destination_root, "-m", "non/existent/path"]) }
+      content = capture(:stderr) { run_generator([destination_root, "-m", "non/existent/path"]) }
 
       assert_match(/The template \[.*\] could not be loaded/, content)
       assert_match(/non\/existent\/path/, content)
@@ -101,58 +83,284 @@ module SharedGeneratorTests
 
   def test_template_is_executed_when_supplied_an_https_path
     path = "https://gist.github.com/josevalim/103208/raw/"
-    template = %{ say "It works!" }
+    template = %{ say "It works!" }.dup
     template.instance_eval "def read; self; end" # Make the string respond to read
 
     check_open = -> *args do
-      assert_equal [ path, 'Accept' => 'application/x-thor-template' ], args
+      assert_equal [ path, "Accept" => "application/x-thor-template" ], args
       template
     end
 
     generator([destination_root], template: path).stub(:open, check_open, template) do
-      quietly { assert_match(/It works!/, capture(:stdout) { generator.invoke_all }) }
+      generator.stub :bundle_command, nil do
+        quietly { assert_match(/It works!/, capture(:stdout) { generator.invoke_all }) }
+      end
     end
   end
 
-  def test_dev_option
-    assert_generates_with_bundler dev: true
-    rails_path = File.expand_path('../../..', Rails.root)
-    assert_file 'Gemfile', /^gem\s+["']rails["'],\s+path:\s+["']#{Regexp.escape(rails_path)}["']$/
+  def test_skip_gemfile
+    assert_not_called(generator([destination_root], skip_gemfile: true), :bundle_command) do
+      quietly { generator.invoke_all }
+      assert_no_file "Gemfile"
+    end
   end
 
-  def test_edge_option
-    assert_generates_with_bundler edge: true
-    assert_file 'Gemfile', %r{^gem\s+["']rails["'],\s+github:\s+["']#{Regexp.escape("rails/rails")}["']$}
+  def test_skip_git
+    run_generator [destination_root, "--skip-git", "--full"]
+    assert_no_file(".gitignore")
+    assert_no_directory(".git")
   end
 
-  def test_skip_gemfile
-    assert_not_called(generator([destination_root], skip_gemfile: true), :bundle_command) do
-      quietly { generator.invoke_all }
-      assert_no_file 'Gemfile'
+  def test_skip_keeps
+    run_generator [destination_root, "--skip-keeps", "--full"]
+
+    assert_file ".gitignore" do |content|
+      assert_no_match(/\.keep/, content)
     end
+
+    assert_no_file("app/models/concerns/.keep")
   end
 
-  def test_skip_bundle
-    assert_not_called(generator([destination_root], skip_bundle: true), :bundle_command) do
-      quietly { generator.invoke_all }
-      # skip_bundle is only about running bundle install, ensure the Gemfile is still
-      # generated.
-      assert_file 'Gemfile'
+  def test_default_frameworks_are_required_when_others_are_removed
+    run_generator [
+      destination_root,
+      "--skip-active-record",
+      "--skip-active-storage",
+      "--skip-action-mailer",
+      "--skip-action-cable",
+      "--skip-sprockets"
+    ]
+
+    assert_file "#{application_path}/config/application.rb", /^require\s+["']rails["']/
+    assert_file "#{application_path}/config/application.rb", /^require\s+["']active_model\/railtie["']/
+    assert_file "#{application_path}/config/application.rb", /^require\s+["']active_job\/railtie["']/
+    assert_file "#{application_path}/config/application.rb", /^# require\s+["']active_record\/railtie["']/
+    assert_file "#{application_path}/config/application.rb", /^# require\s+["']active_storage\/engine["']/
+    assert_file "#{application_path}/config/application.rb", /^require\s+["']action_controller\/railtie["']/
+    assert_file "#{application_path}/config/application.rb", /^# require\s+["']action_mailer\/railtie["']/
+    assert_file "#{application_path}/config/application.rb", /^require\s+["']action_view\/railtie["']/
+    assert_file "#{application_path}/config/application.rb", /^# require\s+["']action_cable\/engine["']/
+    assert_file "#{application_path}/config/application.rb", /^# require\s+["']sprockets\/railtie["']/
+    assert_file "#{application_path}/config/application.rb", /^require\s+["']rails\/test_unit\/railtie["']/
+  end
+
+  def test_generator_without_skips
+    run_generator
+    assert_file "#{application_path}/config/application.rb", /\s+require\s+["']rails\/all["']/
+    assert_file "#{application_path}/config/environments/development.rb" do |content|
+      assert_match(/config\.action_mailer\.raise_delivery_errors = false/, content)
+    end
+    assert_file "#{application_path}/config/environments/test.rb" do |content|
+      assert_match(/config\.action_mailer\.delivery_method = :test/, content)
+    end
+    assert_file "#{application_path}/config/environments/production.rb" do |content|
+      assert_match(/# config\.action_mailer\.raise_delivery_errors = false/, content)
+      assert_match(/^  # config\.require_master_key = true/, content)
     end
   end
 
-  def test_skip_git
-    run_generator [destination_root, '--skip-git', '--full']
-    assert_no_file('.gitignore')
+  def test_gitignore_when_sqlite3
+    run_generator
+
+    assert_file ".gitignore" do |content|
+      assert_match(/sqlite3/, content)
+    end
   end
 
-  def test_skip_keeps
-    run_generator [destination_root, '--skip-keeps', '--full']
+  def test_gitignore_when_non_sqlite3_db
+    run_generator([destination_root, "-d", "mysql"])
 
-    assert_file '.gitignore' do |content|
-      assert_no_match(/\.keep/, content)
+    assert_file ".gitignore" do |content|
+      assert_no_match(/sqlite/i, content)
+    end
+  end
+
+  def test_generator_if_skip_active_record_is_given
+    run_generator [destination_root, "--skip-active-record"]
+    assert_no_directory "#{application_path}/db/"
+    assert_no_file "#{application_path}/config/database.yml"
+    assert_no_file "#{application_path}/app/models/application_record.rb"
+    assert_file "#{application_path}/config/application.rb", /#\s+require\s+["']active_record\/railtie["']/
+    assert_file "test/test_helper.rb" do |helper_content|
+      assert_no_match(/fixtures :all/, helper_content)
+    end
+    assert_file "#{application_path}/bin/setup" do |setup_content|
+      assert_no_match(/db:setup/, setup_content)
+    end
+    assert_file "#{application_path}/bin/update" do |update_content|
+      assert_no_match(/db:migrate/, update_content)
+    end
+    assert_file ".gitignore" do |content|
+      assert_no_match(/sqlite/i, content)
+    end
+  end
+
+  def test_generator_for_active_storage
+    run_generator
+
+    assert_file "#{application_path}/app/assets/javascripts/application.js" do |content|
+      assert_match(/^\/\/= require activestorage/, content)
+    end
+
+    assert_file "#{application_path}/config/environments/development.rb" do |content|
+      assert_match(/config\.active_storage/, content)
+    end
+
+    assert_file "#{application_path}/config/environments/production.rb" do |content|
+      assert_match(/config\.active_storage/, content)
+    end
+
+    assert_file "#{application_path}/config/environments/test.rb" do |content|
+      assert_match(/config\.active_storage/, content)
+    end
+
+    assert_file "#{application_path}/config/storage.yml"
+    assert_directory "#{application_path}/storage"
+    assert_directory "#{application_path}/tmp/storage"
+
+    assert_file ".gitignore" do |content|
+      assert_match(/\/storage\//, content)
+    end
+  end
+
+  def test_generator_if_skip_active_storage_is_given
+    run_generator [destination_root, "--skip-active-storage"]
+
+    assert_file "#{application_path}/config/application.rb", /#\s+require\s+["']active_storage\/engine["']/
+
+    assert_file "#{application_path}/app/assets/javascripts/application.js" do |content|
+      assert_no_match(/^\/\/= require activestorage/, content)
+    end
+
+    assert_file "#{application_path}/config/environments/development.rb" do |content|
+      assert_no_match(/config\.active_storage/, content)
+    end
+
+    assert_file "#{application_path}/config/environments/production.rb" do |content|
+      assert_no_match(/config\.active_storage/, content)
+    end
+
+    assert_file "#{application_path}/config/environments/test.rb" do |content|
+      assert_no_match(/config\.active_storage/, content)
+    end
+
+    assert_no_file "#{application_path}/config/storage.yml"
+    assert_no_directory "#{application_path}/db/migrate"
+    assert_no_directory "#{application_path}/storage"
+    assert_no_directory "#{application_path}/tmp/storage"
+
+    assert_file ".gitignore" do |content|
+      assert_no_match(/\/storage\//, content)
+    end
+  end
+
+  def test_generator_does_not_generate_active_storage_contents_if_skip_active_record_is_given
+    run_generator [destination_root, "--skip-active-record"]
+
+    assert_file "#{application_path}/config/application.rb", /#\s+require\s+["']active_storage\/engine["']/
+
+    assert_file "#{application_path}/app/assets/javascripts/application.js" do |content|
+      assert_no_match(/^\/\/= require activestorage/, content)
+    end
+
+    assert_file "#{application_path}/config/environments/development.rb" do |content|
+      assert_no_match(/config\.active_storage/, content)
+    end
+
+    assert_file "#{application_path}/config/environments/production.rb" do |content|
+      assert_no_match(/config\.active_storage/, content)
+    end
+
+    assert_file "#{application_path}/config/environments/test.rb" do |content|
+      assert_no_match(/config\.active_storage/, content)
+    end
+
+    assert_no_file "#{application_path}/config/storage.yml"
+    assert_no_directory "#{application_path}/db/migrate"
+    assert_no_directory "#{application_path}/storage"
+    assert_no_directory "#{application_path}/tmp/storage"
+
+    assert_file ".gitignore" do |content|
+      assert_no_match(/\/storage\//, content)
+    end
+  end
+
+  def test_generator_if_skip_action_mailer_is_given
+    run_generator [destination_root, "--skip-action-mailer"]
+    assert_file "#{application_path}/config/application.rb", /#\s+require\s+["']action_mailer\/railtie["']/
+    assert_file "#{application_path}/config/environments/development.rb" do |content|
+      assert_no_match(/config\.action_mailer/, content)
+    end
+    assert_file "#{application_path}/config/environments/test.rb" do |content|
+      assert_no_match(/config\.action_mailer/, content)
+    end
+    assert_file "#{application_path}/config/environments/production.rb" do |content|
+      assert_no_match(/config\.action_mailer/, content)
+    end
+    assert_no_directory "#{application_path}/app/mailers"
+    assert_no_directory "#{application_path}/test/mailers"
+  end
+
+  def test_generator_if_skip_action_cable_is_given
+    run_generator [destination_root, "--skip-action-cable"]
+    assert_file "#{application_path}/config/application.rb", /#\s+require\s+["']action_cable\/engine["']/
+    assert_no_file "#{application_path}/config/cable.yml"
+    assert_no_file "#{application_path}/app/assets/javascripts/cable.js"
+    assert_no_directory "#{application_path}/app/assets/javascripts/channels"
+    assert_no_directory "#{application_path}/app/channels"
+    assert_file "Gemfile" do |content|
+      assert_no_match(/redis/, content)
+    end
+  end
+
+  def test_generator_if_skip_sprockets_is_given
+    run_generator [destination_root, "--skip-sprockets"]
+
+    assert_no_file "#{application_path}/config/initializers/assets.rb"
+
+    assert_file "#{application_path}/config/application.rb", /#\s+require\s+["']sprockets\/railtie["']/
+
+    assert_file "Gemfile" do |content|
+      assert_no_match(/sass-rails/, content)
+      assert_no_match(/uglifier/, content)
+      assert_no_match(/coffee-rails/, content)
     end
 
-    assert_no_file('app/models/concerns/.keep')
+    assert_file "#{application_path}/config/environments/development.rb" do |content|
+      assert_no_match(/config\.assets\.debug/, content)
+    end
+
+    assert_file "#{application_path}/config/environments/production.rb" do |content|
+      assert_no_match(/config\.assets\.digest/, content)
+      assert_no_match(/config\.assets\.js_compressor/, content)
+      assert_no_match(/config\.assets\.css_compressor/, content)
+      assert_no_match(/config\.assets\.compile/, content)
+    end
+  end
+
+  def test_generator_for_yarn
+    run_generator
+    assert_file "#{application_path}/package.json", /dependencies/
+    assert_file "#{application_path}/config/initializers/assets.rb", /node_modules/
+
+    assert_file ".gitignore" do |content|
+      assert_match(/node_modules/, content)
+      assert_match(/yarn-error\.log/, content)
+    end
+  end
+
+  def test_generator_for_yarn_skipped
+    run_generator([destination_root, "--skip-yarn"])
+    assert_no_file "#{application_path}/package.json"
+    assert_no_file "#{application_path}/bin/yarn"
+
+    assert_file "#{application_path}/config/initializers/assets.rb" do |content|
+      assert_no_match(/node_modules/, content)
+    end
+
+    assert_file ".gitignore" do |content|
+      assert_no_match(/node_modules/, content)
+      assert_no_match(/yarn-error\.log/, content)
+    end
   end
 end
diff --git a/railties/test/generators/system_test_generator_test.rb b/railties/test/generators/system_test_generator_test.rb
new file mode 100644
index 0000000000..efa70a050b
--- /dev/null
+++ b/railties/test/generators/system_test_generator_test.rb
@@ -0,0 +1,19 @@
+# frozen_string_literal: true
+
+require "generators/generators_test_helper"
+require "rails/generators/rails/system_test/system_test_generator"
+
+class SystemTestGeneratorTest < Rails::Generators::TestCase
+  include GeneratorsTestHelper
+  arguments %w(user)
+
+  def test_system_test_skeleton_is_created
+    run_generator
+    assert_file "test/system/users_test.rb", /class UsersTest < ApplicationSystemTestCase/
+  end
+
+  def test_namespaced_system_test_skeleton_is_created
+    run_generator %w(admin/user)
+    assert_file "test/system/admin/users_test.rb", /class Admin::UsersTest < ApplicationSystemTestCase/
+  end
+end
diff --git a/railties/test/generators/task_generator_test.rb b/railties/test/generators/task_generator_test.rb
index d5bd44b9db..5f162919d8 100644
--- a/railties/test/generators/task_generator_test.rb
+++ b/railties/test/generators/task_generator_test.rb
@@ -1,5 +1,7 @@
-require 'generators/generators_test_helper'
-require 'rails/generators/rails/task/task_generator'
+# frozen_string_literal: true
+
+require "generators/generators_test_helper"
+require "rails/generators/rails/task/task_generator"
 
 class TaskGeneratorTest < Rails::Generators::TestCase
   include GeneratorsTestHelper
@@ -15,10 +17,10 @@ class TaskGeneratorTest < Rails::Generators::TestCase
   end
 
   def test_task_on_revoke
-    task_path = 'lib/tasks/feeds.rake'
+    task_path = "lib/tasks/feeds.rake"
     run_generator
     assert_file task_path
-    run_generator ['feeds'], behavior: :revoke
+    run_generator ["feeds"], behavior: :revoke
     assert_no_file task_path
   end
 end
diff --git a/railties/test/generators/test_runner_in_engine_test.rb b/railties/test/generators/test_runner_in_engine_test.rb
index d37e261fbb..0e15b5e388 100644
--- a/railties/test/generators/test_runner_in_engine_test.rb
+++ b/railties/test/generators/test_runner_in_engine_test.rb
@@ -1,12 +1,14 @@
-require 'generators/plugin_test_helper'
+# frozen_string_literal: true
+
+require "generators/plugin_test_helper"
 
 class TestRunnerInEngineTest < ActiveSupport::TestCase
   include PluginTestHelper
 
   def setup
-    @destination_root = Dir.mktmpdir('bukkits')
+    @destination_root = Dir.mktmpdir("bukkits")
     Dir.chdir(@destination_root) { `bundle exec rails plugin new bukkits --full --skip-bundle` }
-    plugin_file 'test/dummy/db/schema.rb', ''
+    plugin_file "test/dummy/db/schema.rb", ""
   end
 
   def teardown
@@ -14,10 +16,10 @@ class TestRunnerInEngineTest < ActiveSupport::TestCase
   end
 
   def test_rerun_snippet_is_relative_path
-    create_test_file 'post', pass: false
+    create_test_file "post", pass: false
 
-    output = run_test_command('test/post_test.rb')
-    expect = %r{Running:\n\nPostTest\nF\n\nFailure:\nPostTest#test_truth \[[^\]]+test/post_test.rb:6\]:\nwups!\n\nbin/rails test test/post_test.rb:4}
+    output = run_test_command("test/post_test.rb")
+    expect = %r{Running:\n\nPostTest\nF\n\nFailure:\nPostTest#test_truth \[[^\]]+test/post_test\.rb:6\]:\nwups!\n\nbin/rails test test/post_test\.rb:4}
     assert_match expect, output
   end
 
diff --git a/railties/test/generators_test.rb b/railties/test/generators_test.rb
index 291415858c..1735804664 100644
--- a/railties/test/generators_test.rb
+++ b/railties/test/generators_test.rb
@@ -1,6 +1,8 @@
-require 'generators/generators_test_helper'
-require 'rails/generators/rails/model/model_generator'
-require 'rails/generators/test_unit/model/model_generator'
+# frozen_string_literal: true
+
+require "generators/generators_test_helper"
+require "rails/generators/rails/model/model_generator"
+require "rails/generators/test_unit/model/model_generator"
 
 class GeneratorsTest < Rails::Generators::TestCase
   include GeneratorsTestHelper
@@ -15,7 +17,7 @@ class GeneratorsTest < Rails::Generators::TestCase
   end
 
   def test_simple_invoke
-    assert File.exist?(File.join(@path, 'generators', 'model_generator.rb'))
+    assert File.exist?(File.join(@path, "generators", "model_generator.rb"))
     assert_called_with(TestUnit::Generators::ModelGenerator, :start, [["Account"], {}]) do
       Rails::Generators.invoke("test_unit:model", ["Account"])
     end
@@ -23,32 +25,45 @@ class GeneratorsTest < Rails::Generators::TestCase
 
   def test_invoke_when_generator_is_not_found
     name = :unknown
-    output = capture(:stdout){ Rails::Generators.invoke name }
+    output = capture(:stdout) { Rails::Generators.invoke name }
     assert_match "Could not find generator '#{name}'", output
     assert_match "`rails generate --help`", output
   end
 
   def test_generator_suggestions
     name = :migrationz
-    output = capture(:stdout){ Rails::Generators.invoke name }
+    output = capture(:stdout) { Rails::Generators.invoke name }
     assert_match "Maybe you meant 'migration'", output
   end
 
+  def test_generator_suggestions_except_en_locale
+    orig_available_locales = I18n.available_locales
+    orig_default_locale = I18n.default_locale
+    I18n.available_locales = :ja
+    I18n.default_locale = :ja
+    name = :tas
+    output = capture(:stdout) { Rails::Generators.invoke name }
+    assert_match "Maybe you meant 'task', 'job' or", output
+  ensure
+    I18n.available_locales = orig_available_locales
+    I18n.default_locale = orig_default_locale
+  end
+
   def test_generator_multiple_suggestions
     name = :tas
-    output = capture(:stdout){ Rails::Generators.invoke name }
+    output = capture(:stdout) { Rails::Generators.invoke name }
     assert_match "Maybe you meant 'task', 'job' or", output
   end
 
   def test_help_when_a_generator_with_required_arguments_is_invoked_without_arguments
-    output = capture(:stdout){ Rails::Generators.invoke :model, [] }
+    output = capture(:stdout) { Rails::Generators.invoke :model, [] }
     assert_match(/Description:/, output)
   end
 
   def test_should_give_higher_preference_to_rails_generators
-    assert File.exist?(File.join(@path, 'generators', 'model_generator.rb'))
+    assert File.exist?(File.join(@path, "generators", "model_generator.rb"))
     assert_called_with(Rails::Generators::ModelGenerator, :start, [["Account"], {}]) do
-      warnings = capture(:stderr){ Rails::Generators.invoke :model, ["Account"] }
+      warnings = capture(:stderr) { Rails::Generators.invoke :model, ["Account"] }
       assert warnings.empty?
     end
   end
@@ -108,14 +123,14 @@ class GeneratorsTest < Rails::Generators::TestCase
   def test_invoke_with_nested_namespaces
     model_generator = Minitest::Mock.new
     model_generator.expect(:start, nil, [["Account"], {}])
-    assert_called_with(Rails::Generators, :find_by_namespace, ['namespace', 'my:awesome'], returns: model_generator) do
-      Rails::Generators.invoke 'my:awesome:namespace', ["Account"]
+    assert_called_with(Rails::Generators, :find_by_namespace, ["namespace", "my:awesome"], returns: model_generator) do
+      Rails::Generators.invoke "my:awesome:namespace", ["Account"]
     end
     model_generator.verify
   end
 
   def test_rails_generators_help_with_builtin_information
-    output = capture(:stdout){ Rails::Generators.help }
+    output = capture(:stdout) { Rails::Generators.help }
     assert_match(/Rails:/, output)
     assert_match(/^  model$/, output)
     assert_match(/^  scaffold_controller$/, output)
@@ -123,19 +138,19 @@ class GeneratorsTest < Rails::Generators::TestCase
   end
 
   def test_rails_generators_help_does_not_include_app_nor_plugin_new
-    output = capture(:stdout){ Rails::Generators.help }
-    assert_no_match(/app/, output)
+    output = capture(:stdout) { Rails::Generators.help }
+    assert_no_match(/app\W/, output)
     assert_no_match(/[^:]plugin/, output)
   end
 
   def test_rails_generators_with_others_information
-    output = capture(:stdout){ Rails::Generators.help }
+    output = capture(:stdout) { Rails::Generators.help }
     assert_match(/Fixjour:/, output)
     assert_match(/^  fixjour$/, output)
   end
 
   def test_rails_generators_does_not_show_active_record_hooks
-    output = capture(:stdout){ Rails::Generators.help }
+    output = capture(:stdout) { Rails::Generators.help }
     assert_match(/ActiveRecord:/, output)
     assert_match(/^  active_record:fixjour$/, output)
   end
@@ -200,7 +215,7 @@ class GeneratorsTest < Rails::Generators::TestCase
 
     self.class.class_eval(<<-end_eval, __FILE__, __LINE__ + 1)
       class WithOptionsGenerator < Rails::Generators::Base
-        class_option :generate, :default => true
+        class_option :generate, default: true, type: :boolean
       end
     end_eval
 
@@ -214,7 +229,7 @@ class GeneratorsTest < Rails::Generators::TestCase
 
     # Create template
     mkdir_p(File.dirname(template))
-    File.open(template, 'w'){ |f| f.write "empty" }
+    File.open(template, "w") { |f| f.write "empty" }
 
     capture(:stdout) do
       Rails::Generators.invoke :model, ["user"], destination_root: destination_root
@@ -229,18 +244,18 @@ class GeneratorsTest < Rails::Generators::TestCase
 
   def test_source_paths_for_not_namespaced_generators
     mspec = Rails::Generators.find_by_namespace :fixjour
-    assert mspec.source_paths.include?(File.join(Rails.root, "lib", "templates", "fixjour"))
+    assert_includes mspec.source_paths, File.join(Rails.root, "lib", "templates", "fixjour")
   end
 
   def test_usage_with_embedded_ruby
-    require File.expand_path("fixtures/lib/generators/usage_template/usage_template_generator", File.dirname(__FILE__))
-    output = capture(:stdout) { Rails::Generators.invoke :usage_template, ['--help'] }
+    require_relative "fixtures/lib/generators/usage_template/usage_template_generator"
+    output = capture(:stdout) { Rails::Generators.invoke :usage_template, ["--help"] }
     assert_match(/:: 2 ::/, output)
   end
 
   def test_hide_namespace
-    assert !Rails::Generators.hidden_namespaces.include?("special:namespace")
+    assert_not_includes Rails::Generators.hidden_namespaces, "special:namespace"
     Rails::Generators.hide_namespace("special:namespace")
-    assert Rails::Generators.hidden_namespaces.include?("special:namespace")
+    assert_includes Rails::Generators.hidden_namespaces, "special:namespace"
   end
 end
diff --git a/railties/test/initializable_test.rb b/railties/test/initializable_test.rb
index ed9573453b..59fee245f9 100644
--- a/railties/test/initializable_test.rb
+++ b/railties/test/initializable_test.rb
@@ -1,8 +1,9 @@
-require 'abstract_unit'
-require 'rails/initializable'
+# frozen_string_literal: true
 
-module InitializableTests
+require "abstract_unit"
+require "rails/initializable"
 
+module InitializableTests
   class Foo
     include Rails::Initializable
     attr_accessor :foo, :bar
@@ -174,6 +175,11 @@ module InitializableTests
         end
       end
     end
+
+    test "Initializer provides context's class name" do
+      foo = Foo.new
+      assert_equal foo.class, foo.initializers.first.context_class
+    end
   end
 
   class BeforeAfter < ActiveSupport::TestCase
@@ -215,8 +221,8 @@ module InitializableTests
   class WithArgsTest < ActiveSupport::TestCase
     test "running initializers with args" do
       $with_arg = nil
-      WithArgs.new.run_initializers(:default, 'foo')
-      assert_equal 'foo', $with_arg
+      WithArgs.new.run_initializers(:default, "foo")
+      assert_equal "foo", $with_arg
     end
   end
 
diff --git a/railties/test/isolation/abstract_unit.rb b/railties/test/isolation/abstract_unit.rb
index e427614dfa..6568a356d6 100644
--- a/railties/test/isolation/abstract_unit.rb
+++ b/railties/test/isolation/abstract_unit.rb
@@ -1,32 +1,35 @@
+# frozen_string_literal: true
+
 # Note:
 # It is important to keep this file as light as possible
 # the goal for tests that require this is to test booting up
-# rails from an empty state, so anything added here could
+# Rails from an empty state, so anything added here could
 # hide potential failures
 #
 # It is also good to know what is the bare minimum to get
 # Rails booted up.
-require 'fileutils'
+require "fileutils"
 
-require 'bundler/setup' unless defined?(Bundler)
-require 'active_support'
-require 'active_support/testing/autorun'
-require 'active_support/testing/stream'
-require 'active_support/test_case'
+require "bundler/setup" unless defined?(Bundler)
+require "active_support"
+require "active_support/testing/autorun"
+require "active_support/testing/stream"
+require "active_support/test_case"
 
-RAILS_FRAMEWORK_ROOT = File.expand_path("#{File.dirname(__FILE__)}/../../..")
+RAILS_FRAMEWORK_ROOT = File.expand_path("../../..", __dir__)
 
 # These files do not require any others and are needed
 # to run the tests
 require "active_support/core_ext/object/blank"
 require "active_support/testing/isolation"
 require "active_support/core_ext/kernel/reporting"
-require 'tmpdir'
+require "tmpdir"
+require "rails/secrets"
 
 module TestHelpers
   module Paths
     def app_template_path
-      File.join Dir.tmpdir, 'app_template'
+      File.join Dir.tmpdir, "app_template"
     end
 
     def tmp_path(*args)
@@ -53,10 +56,7 @@ module TestHelpers
       @app ||= begin
         ENV["RAILS_ENV"] = env
 
-        # FIXME: shush Sass warning spam, not relevant to testing Railties
-        Kernel.silence_warnings do
-          require "#{app_path}/config/environment"
-        end
+        require "#{app_path}/config/environment"
 
         Rails.application
       end
@@ -65,8 +65,8 @@ module TestHelpers
     end
 
     def extract_body(response)
-      "".tap do |body|
-        response[2].each {|chunk| body << chunk }
+      "".dup.tap do |body|
+        response[2].each { |chunk| body << chunk }
       end
     end
 
@@ -78,34 +78,17 @@ module TestHelpers
       resp = Array(resp)
 
       assert_equal 200, resp[0]
-      assert_match 'text/html', resp[1]["Content-Type"]
-      assert_match 'charset=utf-8', resp[1]["Content-Type"]
+      assert_match "text/html", resp[1]["Content-Type"]
+      assert_match "charset=utf-8", resp[1]["Content-Type"]
       assert extract_body(resp).match(/Yay! You.*re on Rails!/)
     end
-
-    def assert_success(resp)
-      assert_equal 202, resp[0]
-    end
-
-    def assert_missing(resp)
-      assert_equal 404, resp[0]
-    end
-
-    def assert_header(key, value, resp)
-      assert_equal value, resp[1][key.to_s]
-    end
-
-    def assert_body(expected, resp)
-      assert_equal expected, extract_body(resp)
-    end
   end
 
   module Generation
     # Build an application by invoking the generator and going through the whole stack.
     def build_app(options = {})
-      @prev_rails_env = ENV['RAILS_ENV']
-      ENV['RAILS_ENV']       =   "development"
-      ENV['SECRET_KEY_BASE'] ||= SecureRandom.hex(16)
+      @prev_rails_env = ENV["RAILS_ENV"]
+      ENV["RAILS_ENV"] = "development"
 
       FileUtils.rm_rf(app_path)
       FileUtils.cp_r(app_template_path, app_path)
@@ -117,14 +100,9 @@ module TestHelpers
         end
       end
 
-      gemfile_path = "#{app_path}/Gemfile"
-      if options[:gemfile].blank? && File.exist?(gemfile_path)
-        File.delete gemfile_path
-      end
-
       routes = File.read("#{app_path}/config/routes.rb")
-      if routes =~ /(\n\s*end\s*)\Z/
-        File.open("#{app_path}/config/routes.rb", 'w') do |f|
+      if routes =~ /(\n\s*end\s*)\z/
+        File.open("#{app_path}/config/routes.rb", "w") do |f|
           f.puts $` + "\nActiveSupport::Deprecation.silence { match ':controller(/:action(/:id))(.:format)', via: :all }\n" + $1
         end
       end
@@ -158,7 +136,8 @@ module TestHelpers
     end
 
     def teardown_app
-      ENV['RAILS_ENV'] = @prev_rails_env if @prev_rails_env
+      ENV["RAILS_ENV"] = @prev_rails_env if @prev_rails_env
+      FileUtils.rm_rf(tmp_path)
     end
 
     # Make a very basic app, without creating the whole directory structure.
@@ -167,11 +146,11 @@ module TestHelpers
       require "rails"
       require "action_controller/railtie"
       require "action_view/railtie"
-      require 'action_dispatch/middleware/flash'
 
-      @app = Class.new(Rails::Application)
+      @app = Class.new(Rails::Application) do
+        def self.name; "RailtiesTestApp"; end
+      end
       @app.config.eager_load = false
-      @app.secrets.secret_key_base = "3b7cd727ee24e8444053437c36cc66c4"
       @app.config.session_store :cookie_store, key: "_myapp_session"
       @app.config.active_support.deprecation = :log
       @app.config.active_support.test_order = :random
@@ -184,7 +163,7 @@ module TestHelpers
         get "/" => "omg#index"
       end
 
-      require 'rack/test'
+      require "rack/test"
       extend ::Rack::Test::Methods
     end
 
@@ -192,12 +171,12 @@ module TestHelpers
       controller :foo, <<-RUBY
         class FooController < ApplicationController
           def index
-            render text: "foo"
+            render plain: "foo"
           end
         end
       RUBY
 
-      app_file 'config/routes.rb', <<-RUBY
+      app_file "config/routes.rb", <<-RUBY
         Rails.application.routes.draw do
           get ':controller(/:action)'
         end
@@ -214,7 +193,7 @@ module TestHelpers
       def write(file, string)
         path = "#{@path}/#{file}"
         FileUtils.mkdir_p(File.dirname(path))
-        File.open(path, "w") {|f| f.puts string }
+        File.open(path, "w") { |f| f.puts string }
       end
 
       def delete(file)
@@ -227,10 +206,10 @@ module TestHelpers
       FileUtils.mkdir_p(dir)
 
       app = File.readlines("#{app_path}/config/application.rb")
-      app.insert(2, "$:.unshift(\"#{dir}/lib\")")
-      app.insert(3, "require #{name.inspect}")
+      app.insert(4, "$:.unshift(\"#{dir}/lib\")")
+      app.insert(5, "require #{name.inspect}")
 
-      File.open("#{app_path}/config/application.rb", 'r+') do |f|
+      File.open("#{app_path}/config/application.rb", "r+") do |f|
         f.puts app
       end
 
@@ -239,16 +218,92 @@ module TestHelpers
       end
     end
 
-    def script(script)
-      Dir.chdir(app_path) do
-        `#{Gem.ruby} #{app_path}/bin/rails #{script}`
+    # Invoke a bin/rails command inside the app
+    #
+    # allow_failure:: true to return normally if the command exits with
+    #   a non-zero status. By default, this method will raise.
+    # stderr:: true to pass STDERR output straight to the "real" STDERR.
+    #   By default, the STDERR and STDOUT of the process will be
+    #   combined in the returned string.
+    def rails(*args, allow_failure: false, stderr: false)
+      args = args.flatten
+      fork = true
+
+      command = "bin/rails #{Shellwords.join args}#{' 2>&1' unless stderr}"
+
+      # Don't fork if the environment has disabled it
+      fork = false if ENV["NO_FORK"]
+
+      # Don't fork if the runtime isn't able to
+      fork = false if !Process.respond_to?(:fork)
+
+      # Don't fork if we're re-invoking minitest
+      fork = false if args.first == "t" || args.grep(/\Atest(:|\z)/).any?
+
+      if fork
+        out_read, out_write = IO.pipe
+        if stderr
+          err_read, err_write = IO.pipe
+        else
+          err_write = out_write
+        end
+
+        pid = fork do
+          out_read.close
+          err_read.close if err_read
+
+          $stdin.reopen(File::NULL, "r")
+          $stdout.reopen(out_write)
+          $stderr.reopen(err_write)
+
+          at_exit do
+            case $!
+            when SystemExit
+              exit! $!.status
+            when nil
+              exit! 0
+            else
+              err_write.puts "#{$!.class}: #{$!}"
+              exit! 1
+            end
+          end
+
+          Rails.instance_variable_set :@_env, nil
+
+          $-v = $-w = false
+          Dir.chdir app_path unless Dir.pwd == app_path
+
+          ARGV.replace(args)
+          load "./bin/rails"
+
+          exit! 0
+        end
+
+        out_write.close
+
+        if err_read
+          err_write.close
+
+          $stderr.write err_read.read
+        end
+
+        output = out_read.read
+
+        Process.waitpid pid
+
+      else
+        output = `cd #{app_path}; #{command}`
       end
+
+      raise "rails command failed (#{$?.exitstatus}): #{command}\n#{output}" unless allow_failure || $?.success?
+
+      output
     end
 
     def add_to_top_of_config(str)
       environment = File.read("#{app_path}/config/application.rb")
       if environment =~ /(Rails::Application\s*)/
-        File.open("#{app_path}/config/application.rb", 'w') do |f|
+        File.open("#{app_path}/config/application.rb", "w") do |f|
           f.puts $` + $1 + "\n#{str}\n" + $'
         end
       end
@@ -256,8 +311,8 @@ module TestHelpers
 
     def add_to_config(str)
       environment = File.read("#{app_path}/config/application.rb")
-      if environment =~ /(\n\s*end\s*end\s*)\Z/
-        File.open("#{app_path}/config/application.rb", 'w') do |f|
+      if environment =~ /(\n\s*end\s*end\s*)\z/
+        File.open("#{app_path}/config/application.rb", "w") do |f|
           f.puts $` + "\n#{str}\n" + $1
         end
       end
@@ -265,8 +320,8 @@ module TestHelpers
 
     def add_to_env_config(env, str)
       environment = File.read("#{app_path}/config/environments/#{env}.rb")
-      if environment =~ /(\n\s*end\s*)\Z/
-        File.open("#{app_path}/config/environments/#{env}.rb", 'w') do |f|
+      if environment =~ /(\n\s*end\s*)\z/
+        File.open("#{app_path}/config/environments/#{env}.rb", "w") do |f|
           f.puts $` + "\n#{str}\n" + $1
         end
       end
@@ -282,15 +337,17 @@ module TestHelpers
 
     def remove_from_file(file, str)
       contents = File.read(file)
-      contents.sub!(/#{str}/, '')
+      contents.sub!(/#{str}/, "")
       File.write(file, contents)
     end
 
-    def app_file(path, contents, mode = 'w')
-      FileUtils.mkdir_p File.dirname("#{app_path}/#{path}")
-      File.open("#{app_path}/#{path}", mode) do |f|
+    def app_file(path, contents, mode = "w")
+      file_name = "#{app_path}/#{path}"
+      FileUtils.mkdir_p File.dirname(file_name)
+      File.open(file_name, mode) do |f|
         f.puts contents
       end
+      file_name
     end
 
     def remove_file(path)
@@ -302,16 +359,28 @@ module TestHelpers
     end
 
     def use_frameworks(arr)
-      to_remove = [:actionmailer, :activerecord] - arr
+      to_remove = [:actionmailer, :activerecord, :activestorage, :activejob] - arr
 
       if to_remove.include?(:activerecord)
-        remove_from_config 'config.active_record.*'
+        remove_from_config "config.active_record.*"
       end
 
-      $:.reject! {|path| path =~ %r'/(#{to_remove.join('|')})/' }
+      $:.reject! { |path| path =~ %r'/(#{to_remove.join('|')})/' }
     end
 
-    def boot_rails
+    def use_postgresql
+      File.open("#{app_path}/config/database.yml", "w") do |f|
+        f.puts <<-YAML
+        default: &default
+          adapter: postgresql
+          pool: 5
+          database: railties_test
+        development:
+          <<: *default
+        test:
+          <<: *default
+        YAML
+      end
     end
   end
 end
@@ -322,7 +391,9 @@ class ActiveSupport::TestCase
   include TestHelpers::Generation
   include ActiveSupport::Testing::Stream
 
-  self.test_order = :sorted
+  def frozen_error_class
+    Object.const_defined?(:FrozenError) ? FrozenError : RuntimeError
+  end
 end
 
 # Create a scope and build a fixture rails app
@@ -334,7 +405,28 @@ Module.new do
   FileUtils.mkdir(app_template_path)
 
   `#{Gem.ruby} #{RAILS_FRAMEWORK_ROOT}/railties/exe/rails new #{app_template_path} --skip-gemfile --skip-listen --no-rc`
-  File.open("#{app_template_path}/config/boot.rb", 'w') do |f|
+  File.open("#{app_template_path}/config/boot.rb", "w") do |f|
     f.puts "require 'rails/all'"
   end
+
+  # Fake 'Bundler.require' -- we run using the repo's Gemfile, not an
+  # app-specific one: we don't want to require every gem that lists.
+  contents = File.read("#{app_template_path}/config/application.rb")
+  contents.sub!(/^Bundler\.require.*/, "%w(turbolinks).each { |r| require r }")
+  File.write("#{app_template_path}/config/application.rb", contents)
+
+  require "rails"
+
+  require "active_model"
+  require "active_job"
+  require "active_record"
+  require "action_controller"
+  require "action_mailer"
+  require "action_view"
+  require "active_storage"
+  require "action_cable"
+  require "sprockets"
+
+  require "action_view/helpers"
+  require "action_dispatch/routing/route_set"
 end unless defined?(RAILS_ISOLATED_ENGINE)
diff --git a/railties/test/json_params_parsing_test.rb b/railties/test/json_params_parsing_test.rb
new file mode 100644
index 0000000000..65ad9673ff
--- /dev/null
+++ b/railties/test/json_params_parsing_test.rb
@@ -0,0 +1,51 @@
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "action_dispatch"
+require "active_record"
+
+class JsonParamsParsingTest < ActionDispatch::IntegrationTest
+  def test_prevent_null_query
+    # Make sure we have data to find
+    klass = Class.new(ActiveRecord::Base) do
+      def self.name; "Foo"; end
+      establish_connection adapter: "sqlite3", database: ":memory:"
+      connection.create_table "foos" do |t|
+        t.string :title
+        t.timestamps null: false
+      end
+    end
+    klass.create
+    assert klass.first
+
+    app = ->(env) {
+      request = ActionDispatch::Request.new env
+      params = ActionController::Parameters.new request.parameters
+      if params[:t]
+        klass.find_by_title(params[:t])
+      else
+        nil
+      end
+    }
+
+    assert_nil app.call(make_env("t" => nil))
+    assert_nil app.call(make_env("t" => [nil]))
+
+    [[[nil]], [[[nil]]]].each do |data|
+      assert_nil app.call(make_env("t" => data))
+    end
+  ensure
+    klass.connection.drop_table("foos")
+  end
+
+  private
+    def make_env(json)
+      data = JSON.dump json
+      content_length = data.length
+      {
+        "CONTENT_LENGTH" => content_length,
+        "CONTENT_TYPE"   => "application/json",
+        "rack.input"     => StringIO.new(data)
+      }
+    end
+end
diff --git a/railties/test/path_generation_test.rb b/railties/test/path_generation_test.rb
index a16adc72a6..849b183b37 100644
--- a/railties/test/path_generation_test.rb
+++ b/railties/test/path_generation_test.rb
@@ -1,6 +1,8 @@
-require 'abstract_unit'
-require 'active_support/core_ext/object/with_options'
-require 'active_support/core_ext/object/json'
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "active_support/core_ext/object/with_options"
+require "active_support/core_ext/object/json"
 
 class PathGenerationTest < ActiveSupport::TestCase
   attr_reader :app
@@ -30,7 +32,7 @@ class PathGenerationTest < ActiveSupport::TestCase
     end
 
     def make_request(env)
-      Request.new super, self.url_helpers, @block
+      Request.new(super, url_helpers, @block)
     end
   end
 
@@ -38,11 +40,11 @@ class PathGenerationTest < ActiveSupport::TestCase
     host = uri_or_host.host unless path
     path ||= uri_or_host.path
 
-    params = {'PATH_INFO'      => path,
-              'REQUEST_METHOD' => method,
-              'HTTP_HOST'      => host }
+    params = { "PATH_INFO" => path,
+              "REQUEST_METHOD" => method,
+              "HTTP_HOST"      => host }
 
-    params['SCRIPT_NAME'] = script_name if script_name
+    params["SCRIPT_NAME"] = script_name if script_name
 
     status, headers, body = app.call(params)
     new_body = []
@@ -56,12 +58,14 @@ class PathGenerationTest < ActiveSupport::TestCase
     Rails.logger    = Logger.new nil
 
     app = Class.new(Rails::Application) {
+      def self.name; "ScriptNameTestApp"; end
+
       attr_accessor :controller
+
       def initialize
         super
         app = self
         @routes = TestSet.new ->(c) { app.controller = c }
-        secrets.secret_key_base = "foo"
         secrets.secret_token = "foo"
       end
       def app; routes; end
@@ -72,11 +76,11 @@ class PathGenerationTest < ActiveSupport::TestCase
 
     url = URI("http://example.org/blogs")
 
-    send_request(url, 'GET', nil, '/FOO')
-    assert_equal '/FOO/blogs', app.instance.controller.blogs_path
+    send_request(url, "GET", nil, "/FOO")
+    assert_equal "/FOO/blogs", app.instance.controller.blogs_path
 
-    send_request(url, 'GET', nil)
-    assert_equal '/blogs', app.instance.controller.blogs_path
+    send_request(url, "GET", nil)
+    assert_equal "/blogs", app.instance.controller.blogs_path
   ensure
     Rails.logger = original_logger
   end
diff --git a/railties/test/paths_test.rb b/railties/test/paths_test.rb
index 96b54c7264..854b4448a4 100644
--- a/railties/test/paths_test.rb
+++ b/railties/test/paths_test.rb
@@ -1,6 +1,8 @@
-require 'abstract_unit'
-require 'rails/paths'
-require 'minitest/mock'
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "rails/paths"
+require "minitest/mock"
 
 class PathsTest < ActiveSupport::TestCase
   def setup
@@ -103,7 +105,7 @@ class PathsTest < ActiveSupport::TestCase
       @root.add "app", with: "/app"
       @root["app"].autoload_once!
       assert @root["app"].autoload_once?
-      assert @root.autoload_once.include?(@root["app"].expanded.first)
+      assert_includes @root.autoload_once, @root["app"].expanded.first
     end
   end
 
@@ -114,14 +116,14 @@ class PathsTest < ActiveSupport::TestCase
 
     @root["app"].skip_autoload_once!
     assert !@root["app"].autoload_once?
-    assert !@root.autoload_once.include?(@root["app"].expanded.first)
+    assert_not_includes @root.autoload_once, @root["app"].expanded.first
   end
 
   test "it is possible to add a path without assignment and specify it should be loaded only once" do
     File.stub(:exist?, true) do
       @root.add "app", with: "/app", autoload_once: true
       assert @root["app"].autoload_once?
-      assert @root.autoload_once.include?("/app")
+      assert_includes @root.autoload_once, "/app"
     end
   end
 
@@ -129,8 +131,8 @@ class PathsTest < ActiveSupport::TestCase
     File.stub(:exist?, true) do
       @root.add "app", with: ["/app", "/app2"], autoload_once: true
       assert @root["app"].autoload_once?
-      assert @root.autoload_once.include?("/app")
-      assert @root.autoload_once.include?("/app2")
+      assert_includes @root.autoload_once, "/app"
+      assert_includes @root.autoload_once, "/app2"
     end
   end
 
@@ -139,7 +141,7 @@ class PathsTest < ActiveSupport::TestCase
       @root["app"] = "/app"
       @root["app"].autoload_once!
       @root["app"].autoload_once!
-      assert_equal 1, @root.autoload_once.select {|p| p == @root["app"].expanded.first }.size
+      assert_equal 1, @root.autoload_once.select { |p| p == @root["app"].expanded.first }.size
     end
   end
 
@@ -157,7 +159,7 @@ class PathsTest < ActiveSupport::TestCase
       @root["app"] = "/app"
       @root["app"].eager_load!
       assert @root["app"].eager_load?
-      assert @root.eager_load.include?(@root["app"].to_a.first)
+      assert_includes @root.eager_load, @root["app"].to_a.first
     end
   end
 
@@ -168,14 +170,14 @@ class PathsTest < ActiveSupport::TestCase
 
     @root["app"].skip_eager_load!
     assert !@root["app"].eager_load?
-    assert !@root.eager_load.include?(@root["app"].to_a.first)
+    assert_not_includes @root.eager_load, @root["app"].to_a.first
   end
 
   test "it is possible to add a path without assignment and mark it as eager" do
     File.stub(:exist?, true) do
       @root.add "app", with: "/app", eager_load: true
       assert @root["app"].eager_load?
-      assert @root.eager_load.include?("/app")
+      assert_includes @root.eager_load, "/app"
     end
   end
 
@@ -183,8 +185,8 @@ class PathsTest < ActiveSupport::TestCase
     File.stub(:exist?, true) do
       @root.add "app", with: ["/app", "/app2"], eager_load: true
       assert @root["app"].eager_load?
-      assert @root.eager_load.include?("/app")
-      assert @root.eager_load.include?("/app2")
+      assert_includes @root.eager_load, "/app"
+      assert_includes @root.eager_load, "/app2"
     end
   end
 
@@ -193,8 +195,8 @@ class PathsTest < ActiveSupport::TestCase
       @root.add "app", with: "/app", eager_load: true, autoload_once: true
       assert @root["app"].eager_load?
       assert @root["app"].autoload_once?
-      assert @root.eager_load.include?("/app")
-      assert @root.autoload_once.include?("/app")
+      assert_includes @root.eager_load, "/app"
+      assert_includes @root.autoload_once, "/app"
     end
   end
 
@@ -203,7 +205,7 @@ class PathsTest < ActiveSupport::TestCase
       @root["app"] = "/app"
       @root["app"].eager_load!
       @root["app"].eager_load!
-      assert_equal 1, @root.eager_load.select {|p| p == @root["app"].expanded.first }.size
+      assert_equal 1, @root.eager_load.select { |p| p == @root["app"].expanded.first }.size
     end
   end
 
@@ -274,3 +276,23 @@ class PathsTest < ActiveSupport::TestCase
     end
   end
 end
+
+class PathsIntegrationTest < ActiveSupport::TestCase
+  test "A failed symlink is still a valid file" do
+    Dir.mktmpdir do |dir|
+      Dir.chdir(dir) do
+        FileUtils.mkdir_p("foo")
+        File.symlink("foo/doesnotexist.rb", "foo/bar.rb")
+        assert_equal true, File.symlink?("foo/bar.rb")
+
+        root = Rails::Paths::Root.new("foo")
+        root.add "bar.rb"
+
+        exception = assert_raises(RuntimeError) do
+          root["bar.rb"].existent
+        end
+        assert_match File.expand_path("foo/bar.rb"), exception.message
+      end
+    end
+  end
+end
diff --git a/railties/test/rack_logger_test.rb b/railties/test/rack_logger_test.rb
index fcc79b57fb..e47f30d5b6 100644
--- a/railties/test/rack_logger_test.rb
+++ b/railties/test/rack_logger_test.rb
@@ -1,8 +1,10 @@
-require 'abstract_unit'
-require 'active_support/testing/autorun'
-require 'active_support/test_case'
-require 'rails/rack/logger'
-require 'logger'
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "active_support/testing/autorun"
+require "active_support/test_case"
+require "rails/rack/logger"
+require "logger"
 
 module Rails
   module Rack
@@ -20,7 +22,7 @@ module Rails
         def development?; false; end
       end
 
-      class Subscriber < Struct.new(:starts, :finishes)
+      Subscriber = Struct.new(:starts, :finishes) do
         def initialize(starts = [], finishes = [])
           super
         end
@@ -39,7 +41,7 @@ module Rails
       def setup
         @subscriber = Subscriber.new
         @notifier = ActiveSupport::Notifications.notifier
-        @subscription = notifier.subscribe 'request.action_dispatch', subscriber
+        @subscription = notifier.subscribe "request.action_dispatch", subscriber
       end
 
       def teardown
@@ -47,11 +49,11 @@ module Rails
       end
 
       def test_notification
-        logger = TestLogger.new { }
+        logger = TestLogger.new {}
 
-        assert_difference('subscriber.starts.length') do
-          assert_difference('subscriber.finishes.length') do
-            logger.call('REQUEST_METHOD' => 'GET').last.close
+        assert_difference("subscriber.starts.length") do
+          assert_difference("subscriber.finishes.length") do
+            logger.call("REQUEST_METHOD" => "GET").last.close
           end
         end
       end
@@ -62,10 +64,10 @@ module Rails
           raise NotImplementedError
         end
 
-        assert_difference('subscriber.starts.length') do
-          assert_difference('subscriber.finishes.length') do
+        assert_difference("subscriber.starts.length") do
+          assert_difference("subscriber.finishes.length") do
             assert_raises(NotImplementedError) do
-              logger.call 'REQUEST_METHOD' => 'GET'
+              logger.call "REQUEST_METHOD" => "GET"
             end
           end
         end
diff --git a/railties/test/rails_info_controller_test.rb b/railties/test/rails_info_controller_test.rb
index 2e10d63599..878a238f8d 100644
--- a/railties/test/rails_info_controller_test.rb
+++ b/railties/test/rails_info_controller_test.rb
@@ -1,4 +1,6 @@
-require 'abstract_unit'
+# frozen_string_literal: true
+
+require "abstract_unit"
 
 module ActionController
   class Base
@@ -11,8 +13,8 @@ class InfoControllerTest < ActionController::TestCase
 
   def setup
     Rails.application.routes.draw do
-      get '/rails/info/properties' => "rails/info#properties"
-      get '/rails/info/routes'     => "rails/info#routes"
+      get "/rails/info/properties" => "rails/info#properties"
+      get "/rails/info/routes"     => "rails/info#routes"
     end
     @routes = Rails.application.routes
 
@@ -30,7 +32,7 @@ class InfoControllerTest < ActionController::TestCase
   test "info controller renders an error message when request was forbidden" do
     @request.env["REMOTE_ADDR"] = "example.org"
     get :properties
-    assert_select 'p'
+    assert_select "p"
   end
 
   test "info controller allows requests when all requests are considered local" do
@@ -45,7 +47,7 @@ class InfoControllerTest < ActionController::TestCase
 
   test "info controller renders a table with properties" do
     get :properties
-    assert_select 'table'
+    assert_select "table"
   end
 
   test "info controller renders with routes" do
@@ -54,29 +56,29 @@ class InfoControllerTest < ActionController::TestCase
   end
 
   test "info controller returns exact matches" do
-    exact_count = -> { JSON(response.body)['exact'].size }
+    exact_count = -> { JSON(response.body)["exact"].size }
 
-    get :routes, params: { path: 'rails/info/route' }
-    assert exact_count.call == 0, 'should not match incomplete routes'
+    get :routes, params: { path: "rails/info/route" }
+    assert exact_count.call == 0, "should not match incomplete routes"
 
-    get :routes, params: { path: 'rails/info/routes' }
-    assert exact_count.call == 1, 'should match complete routes'
+    get :routes, params: { path: "rails/info/routes" }
+    assert exact_count.call == 1, "should match complete routes"
 
-    get :routes, params: { path: 'rails/info/routes.html' }
-    assert exact_count.call == 1, 'should match complete routes with optional parts'
+    get :routes, params: { path: "rails/info/routes.html" }
+    assert exact_count.call == 1, "should match complete routes with optional parts"
   end
 
   test "info controller returns fuzzy matches" do
-    fuzzy_count = -> { JSON(response.body)['fuzzy'].size }
+    fuzzy_count = -> { JSON(response.body)["fuzzy"].size }
 
-    get :routes, params: { path: 'rails/info' }
-    assert fuzzy_count.call == 2, 'should match incomplete routes'
+    get :routes, params: { path: "rails/info" }
+    assert fuzzy_count.call == 2, "should match incomplete routes"
 
-    get :routes, params: { path: 'rails/info/routes' }
-    assert fuzzy_count.call == 1, 'should match complete routes'
+    get :routes, params: { path: "rails/info/routes" }
+    assert fuzzy_count.call == 1, "should match complete routes"
 
-    get :routes, params: { path: 'rails/info/routes.html' }
-    assert fuzzy_count.call == 0, 'should match optional parts of route literally'
+    get :routes, params: { path: "rails/info/routes.html" }
+    assert fuzzy_count.call == 0, "should match optional parts of route literally"
   end
 
   test "internal routes do not have a default params[:internal] value" do
diff --git a/railties/test/rails_info_test.rb b/railties/test/rails_info_test.rb
index 92e4af25b5..43b60b9144 100644
--- a/railties/test/rails_info_test.rb
+++ b/railties/test/rails_info_test.rb
@@ -1,60 +1,49 @@
-require 'abstract_unit'
+# frozen_string_literal: true
 
-unless defined?(Rails) && defined?(Rails::Info)
-  module Rails
-    class Info; end
-  end
-end
-
-require "active_support/core_ext/kernel/reporting"
+require "abstract_unit"
 
 class InfoTest < ActiveSupport::TestCase
-  def setup
-    Rails.send :remove_const, :Info
-    silence_warnings { load 'rails/info.rb' }
-  end
-
   def test_property_with_block_swallows_exceptions_and_ignores_property
     assert_nothing_raised do
       Rails::Info.module_eval do
-        property('Bogus') {raise}
+        property("Bogus") { raise }
       end
     end
-    assert !property_defined?('Bogus')
+    assert !property_defined?("Bogus")
   end
 
   def test_property_with_string
     Rails::Info.module_eval do
-      property 'Hello', 'World'
+      property "Hello", "World"
     end
-    assert_property 'Hello', 'World'
+    assert_property "Hello", "World"
   end
 
   def test_property_with_block
     Rails::Info.module_eval do
-      property('Goodbye') {'World'}
+      property("Goodbye") { "World" }
     end
-    assert_property 'Goodbye', 'World'
+    assert_property "Goodbye", "World"
   end
 
   def test_rails_version
-    assert_property 'Rails version',
-      File.read(File.realpath('../../../RAILS_VERSION', __FILE__)).chomp
+    assert_property "Rails version",
+      File.read(File.realpath("../../RAILS_VERSION", __dir__)).chomp
   end
 
   def test_html_includes_middleware
     Rails::Info.module_eval do
-      property 'Middleware', ['Rack::Lock', 'Rack::Static']
+      property "Middleware", ["Rack::Lock", "Rack::Static"]
     end
 
     html = Rails::Info.to_html
-    assert html.include?('<tr><td class="name">Middleware</td>')
-    properties.value_for('Middleware').each do |value|
-      assert html.include?("<li>#{CGI.escapeHTML(value)}</li>")
+    assert_includes html, '<tr><td class="name">Middleware</td>'
+    properties.value_for("Middleware").each do |value|
+      assert_includes html, "<li>#{CGI.escapeHTML(value)}</li>"
     end
   end
 
-  protected
+  private
     def properties
       Rails::Info.properties
     end
diff --git a/railties/test/railties/engine_test.rb b/railties/test/railties/engine_test.rb
index fb8a7656d0..339a56c34f 100644
--- a/railties/test/railties/engine_test.rb
+++ b/railties/test/railties/engine_test.rb
@@ -1,10 +1,11 @@
+# frozen_string_literal: true
+
 require "isolation/abstract_unit"
 require "stringio"
 require "rack/test"
 
 module RailtiesTest
   class EngineTest < ActiveSupport::TestCase
-
     include ActiveSupport::Testing::Isolation
     include Rack::Test::Methods
 
@@ -28,17 +29,19 @@ module RailtiesTest
     end
 
     def boot_rails
-      super
       require "#{app_path}/config/environment"
     end
 
+    def migrations
+      migration_root = File.expand_path(ActiveRecord::Migrator.migrations_paths.first, app_path)
+      ActiveRecord::Migrator.migrations(migration_root)
+    end
+
     test "serving sprocket's assets" do
       @plugin.write "app/assets/javascripts/engine.js.erb", "<%= :alert %>();"
       add_to_env_config "development", "config.assets.digest = false"
 
       boot_rails
-      require 'rack/test'
-      extend Rack::Test::Methods
 
       get "/assets/engine.js"
       assert_match "alert()", last_response.body
@@ -84,35 +87,36 @@ module RailtiesTest
         end
       RUBY
 
-      add_to_config "ActiveRecord::Base.timestamped_migrations = false"
-
       boot_rails
 
       Dir.chdir(app_path) do
+        # Install Active Storage migration file first so as not to affect test.
+        `bundle exec rake active_storage:install`
         output = `bundle exec rake bukkits:install:migrations`
 
-        assert File.exist?("#{app_path}/db/migrate/2_create_users.bukkits.rb")
-        assert File.exist?("#{app_path}/db/migrate/3_add_last_name_to_users.bukkits.rb")
-        assert_match(/Copied migration 2_create_users.bukkits.rb from bukkits/, output)
-        assert_match(/Copied migration 3_add_last_name_to_users.bukkits.rb from bukkits/, output)
-        assert_match(/NOTE: Migration 3_create_sessions.rb from bukkits has been skipped/, output)
-        assert_equal 3, Dir["#{app_path}/db/migrate/*.rb"].length
-
-        output = `bundle exec rake railties:install:migrations`.split("\n")
+        ["CreateUsers", "AddLastNameToUsers", "CreateSessions"].each do |migration_name|
+          assert migrations.detect { |migration| migration.name == migration_name }
+        end
+        assert_match(/Copied migration \d+_create_users\.bukkits\.rb from bukkits/, output)
+        assert_match(/Copied migration \d+_add_last_name_to_users\.bukkits\.rb from bukkits/, output)
+        assert_match(/NOTE: Migration \d+_create_sessions\.rb from bukkits has been skipped/, output)
 
-        assert_no_match(/2_create_users/, output.join("\n"))
+        migrations_count = Dir["#{app_path}/db/migrate/*.rb"].length
 
-        bukkits_migration_order = output.index(output.detect{|o| /NOTE: Migration 3_create_sessions.rb from bukkits has been skipped/ =~ o })
-        assert_not_nil bukkits_migration_order, "Expected migration to be skipped"
+        assert_equal migrations.length, migrations_count
 
-        migrations_count = Dir["#{app_path}/db/migrate/*.rb"].length
-        `bundle exec rake railties:install:migrations`
+        output = `bundle exec rake railties:install:migrations`.split("\n")
 
         assert_equal migrations_count, Dir["#{app_path}/db/migrate/*.rb"].length
+
+        assert_no_match(/\d+_create_users/, output.join("\n"))
+
+        bukkits_migration_order = output.index(output.detect { |o| /NOTE: Migration \d+_create_sessions\.rb from bukkits has been skipped/ =~ o })
+        assert_not_nil bukkits_migration_order, "Expected migration to be skipped"
       end
     end
 
-    test 'respects the order of railties when installing migrations' do
+    test "respects the order of railties when installing migrations" do
       @blog = engine "blog" do |plugin|
         plugin.write "lib/blog.rb", <<-RUBY
           module Blog
@@ -137,10 +141,10 @@ module RailtiesTest
       boot_rails
 
       Dir.chdir(app_path) do
-        output  = `bundle exec rake railties:install:migrations`.split("\n")
+        output = `bundle exec rake railties:install:migrations`.split("\n")
 
-        assert_match(/Copied migration \d+_create_users.bukkits.rb from bukkits/, output.first)
-        assert_match(/Copied migration \d+_create_blogs.blog_engine.rb from blog_engine/, output.last)
+        assert_match(/Copied migration \d+_create_users\.bukkits\.rb from bukkits/, output.first)
+        assert_match(/Copied migration \d+_create_blogs\.blog_engine\.rb from blog_engine/, output.second)
       end
     end
 
@@ -173,10 +177,12 @@ module RailtiesTest
       boot_rails
 
       Dir.chdir(app_path) do
-        output  = `bundle exec rake railties:install:migrations`.split("\n")
+        # Install Active Storage migration file first so as not to affect test.
+        `bundle exec rake active_storage:install`
+        output = `bundle exec rake railties:install:migrations`.split("\n")
 
-        assert_match(/Copied migration \d+_create_users.core_engine.rb from core_engine/, output.first)
-        assert_match(/Copied migration \d+_create_keys.api_engine.rb from api_engine/, output.last)
+        assert_match(/Copied migration \d+_create_users\.core_engine\.rb from core_engine/, output.first)
+        assert_match(/Copied migration \d+_create_keys\.api_engine\.rb from api_engine/, output.second)
       end
     end
 
@@ -205,19 +211,22 @@ module RailtiesTest
 
       Dir.chdir(@plugin.path) do
         output = `bundle exec rake app:bukkits:install:migrations`
-        assert File.exist?("#{app_path}/db/migrate/0_add_first_name_to_users.bukkits.rb")
-        assert_match(/Copied migration 0_add_first_name_to_users.bukkits.rb from bukkits/, output)
-        assert_equal 1, Dir["#{app_path}/db/migrate/*.rb"].length
+
+        migration_with_engine_path = migrations.detect { |migration| migration.name == "AddFirstNameToUsers" }
+        assert migration_with_engine_path
+        assert_match(/\/db\/migrate\/\d+_add_first_name_to_users\.bukkits\.rb/, migration_with_engine_path.filename)
+        assert_match(/Copied migration \d+_add_first_name_to_users\.bukkits\.rb from bukkits/, output)
+        assert_equal migrations.length, Dir["#{app_path}/db/migrate/*.rb"].length
       end
     end
 
     test "no rake task without migrations" do
       boot_rails
-      require 'rake'
-      require 'rdoc/task'
-      require 'rake/testtask'
+      require "rake"
+      require "rdoc/task"
+      require "rake/testtask"
       Rails.application.load_tasks
-      assert !Rake::Task.task_defined?('bukkits:install:migrations')
+      assert !Rake::Task.task_defined?("bukkits:install:migrations")
     end
 
     test "puts its lib directory on load path" do
@@ -322,8 +331,6 @@ module RailtiesTest
       RUBY
 
       boot_rails
-      require 'rack/test'
-      extend Rack::Test::Methods
 
       get "/sprokkit"
       assert_equal "I am a Sprokkit", last_response.body
@@ -333,7 +340,7 @@ module RailtiesTest
       controller "foo", <<-RUBY
         class FooController < ActionController::Base
           def index
-            render :text => "foo"
+            render plain: "foo"
           end
         end
       RUBY
@@ -347,7 +354,7 @@ module RailtiesTest
       @plugin.write "app/controllers/bar_controller.rb", <<-RUBY
         class BarController < ActionController::Base
           def index
-            render :text => "bar"
+            render plain: "bar"
           end
         end
       RUBY
@@ -360,14 +367,12 @@ module RailtiesTest
       RUBY
 
       boot_rails
-      require 'rack/test'
-      extend Rack::Test::Methods
 
-      get '/foo'
-      assert_equal 'foo', last_response.body
+      get "/foo"
+      assert_equal "foo", last_response.body
 
-      get '/bar'
-      assert_equal 'bar', last_response.body
+      get "/bar"
+      assert_equal "bar", last_response.body
     end
 
     test "rake tasks lib tasks are loaded" do
@@ -379,9 +384,9 @@ module RailtiesTest
       RUBY
 
       boot_rails
-      require 'rake'
-      require 'rdoc/task'
-      require 'rake/testtask'
+      require "rake"
+      require "rdoc/task"
+      require "rake/testtask"
       Rails.application.load_tasks
       Rake::Task[:foo].invoke
       assert $executed
@@ -392,18 +397,18 @@ module RailtiesTest
         config.i18n.load_path << "#{app_path}/app/locales/en.yml"
       RUBY
 
-      app_file 'app/locales/en.yml', <<-YAML
+      app_file "app/locales/en.yml", <<-YAML
 en:
   bar: "1"
 YAML
 
-      app_file 'config/locales/en.yml', <<-YAML
+      app_file "config/locales/en.yml", <<-YAML
 en:
   foo: "2"
   bar: "2"
 YAML
 
-      @plugin.write 'config/locales/en.yml', <<-YAML
+      @plugin.write "config/locales/en.yml", <<-YAML
 en:
   foo: "3"
 YAML
@@ -444,14 +449,12 @@ YAML
       @plugin.write "app/controllers/admin/foo/bar_controller.rb", <<-RUBY
         class Admin::Foo::BarController < ApplicationController
           def index
-            render text: "Rendered from namespace"
+            render plain: "Rendered from namespace"
           end
         end
       RUBY
 
       boot_rails
-      require 'rack/test'
-      extend Rack::Test::Methods
 
       get "/admin/foo/bar"
       assert_equal 200, last_response.status
@@ -513,7 +516,7 @@ YAML
 
       def call(env)
         response = @app.call(env)
-        response[2].each(&:upcase!)
+        response[2] = response[2].collect(&:upcase)
         response
       end
     end
@@ -546,7 +549,7 @@ YAML
       controller "foo", <<-RUBY
         class FooController < ActionController::Base
           def index
-            render text: params[:username]
+            render plain: params[:username]
           end
         end
       RUBY
@@ -637,11 +640,11 @@ YAML
 
       env = Rack::MockRequest.env_for("/")
       Bukkits::Engine.call(env)
-      assert_equal Bukkits::Engine.routes, env['action_dispatch.routes']
+      assert_equal Bukkits::Engine.routes, env["action_dispatch.routes"]
 
       env = Rack::MockRequest.env_for("/")
       Rails.application.call(env)
-      assert_equal Rails.application.routes, env['action_dispatch.routes']
+      assert_equal Rails.application.routes, env["action_dispatch.routes"]
     end
 
     test "isolated engine should include only its own routes and helpers" do
@@ -710,7 +713,7 @@ YAML
           end
 
           def show
-            render text: foo_path
+            render plain: foo_path
           end
 
           def from_app
@@ -722,7 +725,7 @@ YAML
           end
 
           def polymorphic_path_without_namespace
-            render text: polymorphic_path(Post.new)
+            render plain: polymorphic_path(Post.new)
           end
         end
       RUBY
@@ -845,7 +848,7 @@ YAML
       @plugin.write "app/controllers/bukkits/awesome/foo_controller.rb", <<-RUBY
         class Bukkits::Awesome::FooController < ActionController::Base
           def index
-            render :text => "ok"
+            render plain: "ok"
           end
         end
       RUBY
@@ -892,7 +895,17 @@ YAML
         end
       RUBY
 
-      add_to_config "isolate_namespace AppTemplate"
+      engine "loaded_first" do |plugin|
+        plugin.write "lib/loaded_first.rb", <<-RUBY
+          module AppTemplate
+            module LoadedFirst
+              class Engine < ::Rails::Engine
+                isolate_namespace(AppTemplate)
+              end
+            end
+          end
+        RUBY
+      end
 
       app_file "config/routes.rb", <<-RUBY
         Rails.application.routes.draw do end
@@ -900,7 +913,7 @@ YAML
 
       boot_rails
 
-      assert_equal AppTemplate.railtie_namespace, AppTemplate::Engine
+      assert_equal AppTemplate::LoadedFirst::Engine, AppTemplate.railtie_namespace
     end
 
     test "properly reload routes" do
@@ -967,14 +980,14 @@ YAML
       boot_rails
 
       app_generators = Rails.application.config.generators.options[:rails]
-      assert_equal :mongoid  , app_generators[:orm]
-      assert_equal :liquid   , app_generators[:template_engine]
+      assert_equal :mongoid, app_generators[:orm]
+      assert_equal :liquid, app_generators[:template_engine]
       assert_equal :test_unit, app_generators[:test_framework]
 
       generators = Bukkits::Engine.config.generators.options[:rails]
       assert_equal :data_mapper, generators[:orm]
-      assert_equal :haml      , generators[:template_engine]
-      assert_equal :rspec     , generators[:test_framework]
+      assert_equal :haml, generators[:template_engine]
+      assert_equal :rspec, generators[:test_framework]
     end
 
     test "engine should get default generators with ability to overwrite them" do
@@ -990,10 +1003,10 @@ YAML
 
       generators = Bukkits::Engine.config.generators.options[:rails]
       assert_equal :active_record, generators[:orm]
-      assert_equal :rspec        , generators[:test_framework]
+      assert_equal :rspec, generators[:test_framework]
 
       app_generators = Rails.application.config.generators.options[:rails]
-      assert_equal :test_unit    , app_generators[:test_framework]
+      assert_equal :test_unit, app_generators[:test_framework]
     end
 
     test "do not create table_name_prefix method if it already exists" do
@@ -1028,7 +1041,7 @@ YAML
 
       # check expanding paths
       engine_dir = @plugin.path.chomp("/").split("/").last
-      engine_path = File.join(@plugin.path, '..', engine_dir)
+      engine_path = File.join(@plugin.path, "..", engine_dir)
       assert_equal Bukkits::Engine.instance, Rails::Engine.find(engine_path)
     end
 
@@ -1230,13 +1243,12 @@ YAML
                 fullpath: \#{request.fullpath}
                 path: \#{request.path}
               TEXT
-              render text: text
+              render plain: text
             end
           end
         end
       RUBY
 
-
       app_file "config/routes.rb", <<-RUBY
         Rails.application.routes.draw do
           mount Bukkits::Engine => "/"
@@ -1268,7 +1280,7 @@ YAML
       app_file "app/controllers/bar_controller.rb", <<-RUBY
         class BarController < ApplicationController
           def index
-            render text: bukkits.bukkit_path
+            render plain: bukkits.bukkit_path
           end
         end
       RUBY
@@ -1286,22 +1298,21 @@ YAML
         end
       RUBY
 
-
       @plugin.write "app/controllers/bukkits/bukkit_controller.rb", <<-RUBY
         class Bukkits::BukkitController < ActionController::Base
           def index
-            render text: main_app.bar_path
+            render plain: main_app.bar_path
           end
         end
       RUBY
 
       boot_rails
 
-      get("/bukkits/bukkit", {}, {'SCRIPT_NAME' => '/foo'})
-      assert_equal '/foo/bar', last_response.body
+      get("/bukkits/bukkit", {}, { "SCRIPT_NAME" => "/foo" })
+      assert_equal "/foo/bar", last_response.body
 
-      get("/bar", {}, {'SCRIPT_NAME' => '/foo'})
-      assert_equal '/foo/bukkits/bukkit', last_response.body
+      get("/bar", {}, { "SCRIPT_NAME" => "/foo" })
+      assert_equal "/foo/bukkits/bukkit", last_response.body
     end
 
     test "paths are properly generated when application is mounted at sub-path and relative_url_root is set" do
@@ -1318,7 +1329,7 @@ YAML
       app_file "app/controllers/bar_controller.rb", <<-RUBY
         class BarController < ApplicationController
           def index
-            render text: bukkits.bukkit_path
+            render plain: bukkits.bukkit_path
           end
         end
       RUBY
@@ -1339,18 +1350,148 @@ YAML
       @plugin.write "app/controllers/bukkits/bukkit_controller.rb", <<-RUBY
         class Bukkits::BukkitController < ActionController::Base
           def index
-            render text: main_app.bar_path
+            render plain: main_app.bar_path
+          end
+        end
+      RUBY
+
+      boot_rails
+
+      get("/bukkits/bukkit", {}, { "SCRIPT_NAME" => "/foo" })
+      assert_equal "/foo/bar", last_response.body
+
+      get("/bar", {}, { "SCRIPT_NAME" => "/foo" })
+      assert_equal "/foo/bukkits/bukkit", last_response.body
+    end
+
+    test "isolated engine can be mounted under multiple static locations" do
+      app_file "app/controllers/foos_controller.rb", <<-RUBY
+        class FoosController < ApplicationController
+          def through_fruits
+            render plain: fruit_bukkits.posts_path
+          end
+
+          def through_vegetables
+            render plain: vegetable_bukkits.posts_path
+          end
+        end
+      RUBY
+
+      app_file "config/routes.rb", <<-RUBY
+        Rails.application.routes.draw do
+          scope "/fruits" do
+            mount Bukkits::Engine => "/bukkits", as: :fruit_bukkits
+          end
+
+          scope "/vegetables" do
+            mount Bukkits::Engine => "/bukkits", as: :vegetable_bukkits
+          end
+
+          get "/through_fruits" => "foos#through_fruits"
+          get "/through_vegetables" => "foos#through_vegetables"
+        end
+      RUBY
+
+      @plugin.write "config/routes.rb", <<-RUBY
+        Bukkits::Engine.routes.draw do
+          resources :posts, only: :index
+        end
+      RUBY
+
+      boot_rails
+
+      get("/through_fruits")
+      assert_equal "/fruits/bukkits/posts", last_response.body
+
+      get("/through_vegetables")
+      assert_equal "/vegetables/bukkits/posts", last_response.body
+    end
+
+    test "isolated engine can be mounted under multiple dynamic locations" do
+      app_file "app/controllers/foos_controller.rb", <<-RUBY
+        class FoosController < ApplicationController
+          def through_fruits
+            render plain: fruit_bukkits.posts_path(fruit_id: 1)
+          end
+
+          def through_vegetables
+            render plain: vegetable_bukkits.posts_path(vegetable_id: 1)
+          end
+        end
+      RUBY
+
+      app_file "config/routes.rb", <<-RUBY
+        Rails.application.routes.draw do
+          resources :fruits do
+            mount Bukkits::Engine => "/bukkits"
+          end
+
+          resources :vegetables do
+            mount Bukkits::Engine => "/bukkits"
+          end
+
+          get "/through_fruits" => "foos#through_fruits"
+          get "/through_vegetables" => "foos#through_vegetables"
+        end
+      RUBY
+
+      @plugin.write "config/routes.rb", <<-RUBY
+        Bukkits::Engine.routes.draw do
+          resources :posts, only: :index
+        end
+      RUBY
+
+      boot_rails
+
+      get("/through_fruits")
+      assert_equal "/fruits/1/bukkits/posts", last_response.body
+
+      get("/through_vegetables")
+      assert_equal "/vegetables/1/bukkits/posts", last_response.body
+    end
+
+    test "route helpers resolve script name correctly when called with different script name from current one" do
+      @plugin.write "app/controllers/posts_controller.rb", <<-RUBY
+        class PostsController < ActionController::Base
+          def index
+            render plain: fruit_bukkits.posts_path(fruit_id: 2)
           end
         end
       RUBY
 
+      app_file "config/routes.rb", <<-RUBY
+        Rails.application.routes.draw do
+          resources :fruits do
+            mount Bukkits::Engine => "/bukkits"
+          end
+        end
+      RUBY
+
+      @plugin.write "config/routes.rb", <<-RUBY
+        Bukkits::Engine.routes.draw do
+          resources :posts, only: :index
+        end
+      RUBY
+
       boot_rails
 
-      get("/bukkits/bukkit", {}, {'SCRIPT_NAME' => '/foo'})
-      assert_equal '/foo/bar', last_response.body
+      get("/fruits/1/bukkits/posts")
+      assert_equal "/fruits/2/bukkits/posts", last_response.body
+    end
 
-      get("/bar", {}, {'SCRIPT_NAME' => '/foo'})
-      assert_equal '/foo/bukkits/bukkit', last_response.body
+    test "active_storage:install task works within engine" do
+      @plugin.write "Rakefile", <<-RUBY
+        APP_RAKEFILE = '#{app_path}/Rakefile'
+        load 'rails/tasks/engine.rake'
+      RUBY
+
+      Dir.chdir(@plugin.path) do
+        output = `bundle exec rake app:active_storage:install`
+        assert $?.success?, output
+
+        active_storage_migration = migrations.detect { |migration| migration.name == "CreateActiveStorageTables" }
+        assert active_storage_migration
+      end
     end
 
   private
diff --git a/railties/test/railties/generators_test.rb b/railties/test/railties/generators_test.rb
index b85e16c040..8383cb3050 100644
--- a/railties/test/railties/generators_test.rb
+++ b/railties/test/railties/generators_test.rb
@@ -1,7 +1,9 @@
+# frozen_string_literal: true
+
 RAILS_ISOLATED_ENGINE = true
 require "isolation/abstract_unit"
 
-require 'generators/generators_test_helper'
+require "generators/generators_test_helper"
 require "rails/generators/test_case"
 
 module RailtiesTests
@@ -9,7 +11,7 @@ module RailtiesTests
     include ActiveSupport::Testing::Isolation
 
     def destination_root
-      tmp_path 'foo_bar'
+      tmp_path "foo_bar"
     end
 
     def tmp_path(*args)
@@ -18,7 +20,7 @@ module RailtiesTests
     end
 
     def engine_path
-      tmp_path('foo_bar')
+      tmp_path("foo_bar")
     end
 
     def bundled_rails(cmd)
@@ -29,7 +31,7 @@ module RailtiesTests
       `#{Gem.ruby} #{RAILS_FRAMEWORK_ROOT}/railties/exe/rails #{cmd}`
     end
 
-    def build_engine(is_mountable=false)
+    def build_engine(is_mountable = false)
       FileUtils.rm_rf(engine_path)
       FileUtils.mkdir_p(engine_path)
 
@@ -39,7 +41,7 @@ module RailtiesTests
 
       Dir.chdir(engine_path) do
         File.open("Gemfile", "w") do |f|
-          f.write <<-GEMFILE.gsub(/^ {12}/, '')
+          f.write <<-GEMFILE.gsub(/^ {12}/, "")
             source "https://rubygems.org"
 
             gem 'rails', path: '#{RAILS_FRAMEWORK_ROOT}'
diff --git a/railties/test/railties/mounted_engine_test.rb b/railties/test/railties/mounted_engine_test.rb
index fb2071c7c3..48f0fbc80f 100644
--- a/railties/test/railties/mounted_engine_test.rb
+++ b/railties/test/railties/mounted_engine_test.rb
@@ -1,10 +1,12 @@
-require 'isolation/abstract_unit'
+# frozen_string_literal: true
+
+require "isolation/abstract_unit"
 
 module ApplicationTests
   class ApplicationRoutingTest < ActiveSupport::TestCase
-     require 'rack/test'
-     include Rack::Test::Methods
-     include ActiveSupport::Testing::Isolation
+    require "rack/test"
+    include Rack::Test::Methods
+    include ActiveSupport::Testing::Isolation
 
     def setup
       build_app
@@ -15,7 +17,7 @@ module ApplicationTests
       @plugin = engine "blog"
       @metrics_plugin = engine "metrics"
 
-      app_file 'config/routes.rb', <<-RUBY
+      app_file "config/routes.rb", <<-RUBY
         Rails.application.routes.draw do
           mount Weblog::Engine, :at => '/', :as => 'weblog'
           resources :posts
@@ -34,7 +36,6 @@ module ApplicationTests
         end
       RUBY
 
-
       @simple_plugin.write "lib/weblog.rb", <<-RUBY
         module Weblog
           class Engine < ::Rails::Engine
@@ -51,7 +52,7 @@ module ApplicationTests
       @simple_plugin.write "app/controllers/weblogs_controller.rb", <<-RUBY
         class WeblogsController < ActionController::Base
           def index
-            render text: request.url
+            render plain: request.url
           end
         end
       RUBY
@@ -75,7 +76,7 @@ module ApplicationTests
         module Metrics
           class GeneratingController < ActionController::Base
             def generate_blog_route
-              render text: blog.post_path(1)
+              render plain: blog.post_path(1)
             end
 
             def generate_blog_route_in_view
@@ -112,6 +113,7 @@ module ApplicationTests
       @plugin.write "config/routes.rb", <<-RUBY
         Blog::Engine.routes.draw do
           resources :posts
+          get '/different_context', to: 'posts#different_context'
           get '/generate_application_route', to: 'posts#generate_application_route'
           get '/application_route_in_view', to: 'posts#application_route_in_view'
           get '/engine_polymorphic_path', to: 'posts#engine_polymorphic_path'
@@ -123,14 +125,18 @@ module ApplicationTests
         module Blog
           class PostsController < ActionController::Base
             def index
-              render text: blog.post_path(1)
+              render plain: blog.post_path(1)
+            end
+
+            def different_context
+              render plain: blog.post_path(1, user: "ada")
             end
 
             def generate_application_route
               path = main_app.url_for(controller: "/main",
                                  action: "index",
                                  only_path: true)
-              render text: path
+              render plain: path
             end
 
             def application_route_in_view
@@ -138,11 +144,11 @@ module ApplicationTests
             end
 
             def engine_polymorphic_path
-              render text: polymorphic_path(Post.new)
+              render plain: polymorphic_path(Post.new)
             end
 
             def engine_asset_path
-              render inline: "<%= asset_path 'images/foo.png' %>"
+              render inline: "<%= asset_path 'images/foo.png', skip_pipeline: true %>"
             end
           end
         end
@@ -151,7 +157,7 @@ module ApplicationTests
       app_file "app/controllers/application_generating_controller.rb", <<-RUBY
         class ApplicationGeneratingController < ActionController::Base
           def engine_route
-            render text: blog.posts_path
+            render plain: blog.posts_path
           end
 
           def engine_route_in_view
@@ -159,7 +165,7 @@ module ApplicationTests
           end
 
           def weblog_engine_route
-            render text: weblog.weblogs_path
+            render plain: weblog.weblogs_path
           end
 
           def weblog_engine_route_in_view
@@ -167,20 +173,18 @@ module ApplicationTests
           end
 
           def url_for_engine_route
-            render text: blog.url_for(controller: "blog/posts", action: "index", user: "john", only_path: true)
+            render plain: blog.url_for(controller: "blog/posts", action: "index", user: "john", only_path: true)
           end
 
           def polymorphic_route
-            render text: polymorphic_url([blog, Blog::Post.new])
+            render plain: polymorphic_url([blog, Blog::Post.new])
           end
 
           def application_polymorphic_path
-            render text: polymorphic_path(Blog::Post.new)
+            render plain: polymorphic_path(Blog::Post.new)
           end
         end
       RUBY
-
-      boot_rails
     end
 
     def teardown
@@ -199,8 +203,12 @@ module ApplicationTests
       get "/john/blog/posts"
       assert_equal "/john/blog/posts/1", last_response.body
 
+      # test generating engine route from engine with a different context
+      get "/john/blog/different_context"
+      assert_equal "/ada/blog/posts/1", last_response.body
+
       # test generating engine's route from engine with default_url_options
-      get "/john/blog/posts", {}, 'SCRIPT_NAME' => "/foo"
+      get "/john/blog/posts", {}, { "SCRIPT_NAME" => "/foo" }
       assert_equal "/foo/john/blog/posts/1", last_response.body
 
       # test generating engine's route from application
@@ -214,10 +222,10 @@ module ApplicationTests
       assert_equal "/john/blog/posts", last_response.body
 
       # test generating engine's route from application with default_url_options
-      get "/engine_route", {}, 'SCRIPT_NAME' => "/foo"
+      get "/engine_route", {}, { "SCRIPT_NAME" => "/foo" }
       assert_equal "/foo/anonymous/blog/posts", last_response.body
 
-      get "/url_for_engine_route", {}, 'SCRIPT_NAME' => "/foo"
+      get "/url_for_engine_route", {}, { "SCRIPT_NAME" => "/foo" }
       assert_equal "/foo/john/blog/posts", last_response.body
 
       # test generating application's route from engine
@@ -229,21 +237,20 @@ module ApplicationTests
 
       # test generating engine's route from other engine
       get "/metrics/generate_blog_route"
-      assert_equal '/anonymous/blog/posts/1', last_response.body
+      assert_equal "/anonymous/blog/posts/1", last_response.body
 
       get "/metrics/generate_blog_route_in_view"
-      assert_equal '/anonymous/blog/posts/1', last_response.body
+      assert_equal "/anonymous/blog/posts/1", last_response.body
 
       # test generating engine's route from other engine with default_url_options
-      get "/metrics/generate_blog_route", {}, 'SCRIPT_NAME' => '/foo'
-      assert_equal '/foo/anonymous/blog/posts/1', last_response.body
-
-      get "/metrics/generate_blog_route_in_view", {}, 'SCRIPT_NAME' => '/foo'
-      assert_equal '/foo/anonymous/blog/posts/1', last_response.body
+      get "/metrics/generate_blog_route", {}, { "SCRIPT_NAME" => "/foo" }
+      assert_equal "/foo/anonymous/blog/posts/1", last_response.body
 
+      get "/metrics/generate_blog_route_in_view", {}, { "SCRIPT_NAME" => "/foo" }
+      assert_equal "/foo/anonymous/blog/posts/1", last_response.body
 
       # test generating application's route from engine with default_url_options
-      get "/someone/blog/generate_application_route", {}, 'SCRIPT_NAME' => '/foo'
+      get "/someone/blog/generate_application_route", {}, { "SCRIPT_NAME" => "/foo" }
       assert_equal "/foo/", last_response.body
 
       # test polymorphic routes
diff --git a/railties/test/railties/railtie_test.rb b/railties/test/railties/railtie_test.rb
index 5042d628cf..359ab0fdae 100644
--- a/railties/test/railties/railtie_test.rb
+++ b/railties/test/railties/railtie_test.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require "isolation/abstract_unit"
 
 module RailtiesTest
@@ -6,7 +8,6 @@ module RailtiesTest
 
     def setup
       build_app
-      boot_rails
       FileUtils.rm_rf("#{app_path}/config/environments")
       require "rails/all"
     end
@@ -80,6 +81,13 @@ module RailtiesTest
       assert_equal app_path, $before_configuration
     end
 
+    test "before_configuration callbacks run as soon as the application constant inherits from Rails::Application" do
+      $before_configuration = false
+      class Foo < Rails::Railtie ; config.before_configuration { $before_configuration = true } ; end
+      class Application < Rails::Application ; end
+      assert $before_configuration
+    end
+
     test "railtie can add after_initialize callbacks" do
       $after_initialize = false
       class Foo < Rails::Railtie ; config.after_initialize { $after_initialize = true } ; end
@@ -100,9 +108,9 @@ module RailtiesTest
       require "#{app_path}/config/environment"
 
       assert !$ran_block
-      require 'rake'
-      require 'rake/testtask'
-      require 'rdoc/task'
+      require "rake"
+      require "rake/testtask"
+      require "rdoc/task"
 
       Rails.application.load_tasks
       assert $ran_block
@@ -124,12 +132,12 @@ module RailtiesTest
       require "#{app_path}/config/environment"
 
       assert_equal [], $ran_block
-      require 'rake'
-      require 'rake/testtask'
-      require 'rdoc/task'
+      require "rake"
+      require "rake/testtask"
+      require "rdoc/task"
 
       Rails.application.load_tasks
-      assert $ran_block.include?("my_tie")
+      assert_includes $ran_block, "my_tie"
     end
 
     test "generators block is executed when MyApp.load_generators is called" do
@@ -197,8 +205,8 @@ module RailtiesTest
     test "we can change our environment if we want to" do
       begin
         original_env = Rails.env
-        Rails.env = 'foo'
-        assert_equal('foo', Rails.env)
+        Rails.env = "foo"
+        assert_equal("foo", Rails.env)
       ensure
         Rails.env = original_env
         assert_equal(original_env, Rails.env)
diff --git a/railties/test/secrets_test.rb b/railties/test/secrets_test.rb
new file mode 100644
index 0000000000..06877bc76a
--- /dev/null
+++ b/railties/test/secrets_test.rb
@@ -0,0 +1,178 @@
+# frozen_string_literal: true
+
+require "isolation/abstract_unit"
+require "rails/secrets"
+
+class Rails::SecretsTest < ActiveSupport::TestCase
+  include ActiveSupport::Testing::Isolation
+
+  setup :build_app
+  teardown :teardown_app
+
+  test "setting read to false skips parsing" do
+    run_secrets_generator do
+      Rails::Secrets.write(<<-end_of_secrets)
+        production:
+          yeah_yeah: lets-walk-in-the-cool-evening-light
+      end_of_secrets
+
+      add_to_env_config("production", "config.read_encrypted_secrets = false")
+      app("production")
+
+      assert_not Rails.application.secrets.yeah_yeah
+    end
+  end
+
+  test "raises when reading secrets without a key" do
+    run_secrets_generator do
+      FileUtils.rm("config/secrets.yml.key")
+
+      assert_raises Rails::Secrets::MissingKeyError do
+        Rails::Secrets.key
+      end
+    end
+  end
+
+  test "reading with ENV variable" do
+    run_secrets_generator do
+      begin
+        old_key = ENV["RAILS_MASTER_KEY"]
+        ENV["RAILS_MASTER_KEY"] = IO.binread("config/secrets.yml.key").strip
+        FileUtils.rm("config/secrets.yml.key")
+
+        assert_match "# production:\n#   external_api_key:", Rails::Secrets.read
+      ensure
+        ENV["RAILS_MASTER_KEY"] = old_key
+      end
+    end
+  end
+
+  test "reading from key file" do
+    run_secrets_generator do
+      File.binwrite("config/secrets.yml.key", "00112233445566778899aabbccddeeff")
+
+      assert_equal "00112233445566778899aabbccddeeff", Rails::Secrets.key
+    end
+  end
+
+  test "editing" do
+    run_secrets_generator do
+      decrypted_path = nil
+
+      Rails::Secrets.read_for_editing do |tmp_path|
+        decrypted_path = tmp_path
+
+        assert_match(/# production:\n#   external_api_key/, File.read(tmp_path))
+
+        File.write(tmp_path, "Empty streets, empty nights. The Downtown Lights.")
+      end
+
+      assert_not File.exist?(decrypted_path)
+      assert_equal "Empty streets, empty nights. The Downtown Lights.", Rails::Secrets.read
+    end
+  end
+
+  test "merging secrets with encrypted precedence" do
+    run_secrets_generator do
+      File.write("config/secrets.yml", <<-end_of_secrets)
+        production:
+          yeah_yeah: lets-go-walking-down-this-empty-street
+      end_of_secrets
+
+      Rails::Secrets.write(<<-end_of_secrets)
+        production:
+          yeah_yeah: lets-walk-in-the-cool-evening-light
+      end_of_secrets
+
+      add_to_env_config("production", "config.read_encrypted_secrets = true")
+      app("production")
+
+      assert_equal "lets-walk-in-the-cool-evening-light", Rails.application.secrets.yeah_yeah
+    end
+  end
+
+  test "refer secrets inside env config" do
+    run_secrets_generator do
+      Rails::Secrets.write(<<-end_of_yaml)
+        production:
+          some_secret: yeah yeah
+      end_of_yaml
+
+      add_to_env_config "production", <<-end_of_config
+        config.dereferenced_secret = Rails.application.secrets.some_secret
+      end_of_config
+
+      app("production")
+
+      assert_equal "yeah yeah", Rails.application.config.dereferenced_secret
+    end
+  end
+
+  test "do not update secrets.yml.enc when secretes do not change" do
+    run_secrets_generator do
+      Rails::Secrets.read_for_editing do |tmp_path|
+        File.write(tmp_path, "Empty streets, empty nights. The Downtown Lights.")
+      end
+
+      FileUtils.cp("config/secrets.yml.enc", "config/secrets.yml.enc.bk")
+
+      Rails::Secrets.read_for_editing do |tmp_path|
+        File.write(tmp_path, "Empty streets, empty nights. The Downtown Lights.")
+      end
+
+      assert_equal File.read("config/secrets.yml.enc.bk"), File.read("config/secrets.yml.enc")
+    end
+  end
+
+  test "can read secrets written in binary" do
+    run_secrets_generator do
+      secrets = <<-end_of_secrets
+        production:
+          api_key: 00112233445566778899aabbccddeeff…
+      end_of_secrets
+
+      Rails::Secrets.write(secrets.dup.force_encoding(Encoding::ASCII_8BIT))
+
+      Rails::Secrets.read_for_editing do |tmp_path|
+        assert_match(/production:\n\s*api_key: 00112233445566778899aabbccddeeff…\n/, File.read(tmp_path))
+      end
+
+      app("production")
+
+      assert_equal "00112233445566778899aabbccddeeff…", Rails.application.secrets.api_key
+    end
+  end
+
+  test "can read secrets written in non-binary" do
+    run_secrets_generator do
+      secrets = <<-end_of_secrets
+        production:
+          api_key: 00112233445566778899aabbccddeeff…
+      end_of_secrets
+
+      Rails::Secrets.write(secrets)
+
+      Rails::Secrets.read_for_editing do |tmp_path|
+        assert_equal(secrets.dup.force_encoding(Encoding::ASCII_8BIT), IO.binread(tmp_path))
+      end
+
+      app("production")
+
+      assert_equal "00112233445566778899aabbccddeeff…", Rails.application.secrets.api_key
+    end
+  end
+
+  private
+    def run_secrets_generator
+      Dir.chdir(app_path) do
+        File.write("config/secrets.yml.key", "f731758c639da2604dfb6bf3d1025de8")
+        File.write("config/secrets.yml.enc", "sEB0mHxDbeP1/KdnMk00wyzPFACl9K6t0cZWn5/Mfx/YbTHvnI07vrneqHg9kaH3wOS7L6pIQteu1P077OtE4BSx/ZRc/sgQPHyWu/tXsrfHqnPNpayOF/XZqizE91JacSFItNMWpuPsp9ynbzz+7cGhoB1S4aPNIU6u0doMrzdngDbijsaAFJmsHIQh6t/QHoJx--8aMoE0PvUWmw1Iqz--ldFqnM/K0g9k17M8PKoN/Q==")
+
+        add_to_config <<-RUBY
+          config.read_encrypted_secrets = true
+        RUBY
+
+        yield
+      end
+    end
+end
diff --git a/railties/test/test_unit/reporter_test.rb b/railties/test/test_unit/reporter_test.rb
index 0d64b48550..ad852d0f35 100644
--- a/railties/test/test_unit/reporter_test.rb
+++ b/railties/test/test_unit/reporter_test.rb
@@ -1,6 +1,8 @@
-require 'abstract_unit'
-require 'rails/test_unit/reporter'
-require 'minitest/mock'
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "rails/test_unit/reporter"
+require "minitest/mock"
 
 class TestUnitReporterTest < ActiveSupport::TestCase
   class ExampleTest < Minitest::Test
@@ -16,7 +18,7 @@ class TestUnitReporterTest < ActiveSupport::TestCase
     @reporter.record(failed_test)
     @reporter.report
 
-    assert_match %r{^bin/rails test .*test/test_unit/reporter_test.rb:\d+$}, @output.string
+    assert_match %r{^bin/rails test .*test/test_unit/reporter_test\.rb:\d+$}, @output.string
     assert_rerun_snippet_count 1
   end
 
@@ -33,7 +35,7 @@ class TestUnitReporterTest < ActiveSupport::TestCase
     @reporter.record(passing_test)
     @reporter.record(skipped_test)
     @reporter.report
-    assert_no_match 'Failed tests:', @output.string
+    assert_no_match "Failed tests:", @output.string
     assert_rerun_snippet_count 0
   end
 
@@ -52,7 +54,7 @@ class TestUnitReporterTest < ActiveSupport::TestCase
       @reporter.record(failed_test)
       @reporter.report
 
-      assert_match %r{^bin/test .*test/test_unit/reporter_test.rb:\d+$}, @output.string
+      assert_match %r{^bin/test .*test/test_unit/reporter_test\.rb:\d+$}, @output.string
     ensure
       Rails::TestUnitReporter.executable = original_executable
     end
@@ -62,7 +64,7 @@ class TestUnitReporterTest < ActiveSupport::TestCase
     @reporter.record(failed_test)
     @reporter.report
 
-    expect = %r{\AF\n\nFailure:\nTestUnitReporterTest::ExampleTest#woot \[[^\]]+\]:\nboo\n\nbin/rails test test/test_unit/reporter_test.rb:\d+\n\n\z}
+    expect = %r{\AF\n\nFailure:\nTestUnitReporterTest::ExampleTest#woot \[[^\]]+\]:\nboo\n\nbin/rails test test/test_unit/reporter_test\.rb:\d+\n\n\z}
     assert_match expect, @output.string
   end
 
@@ -70,7 +72,7 @@ class TestUnitReporterTest < ActiveSupport::TestCase
     @reporter.record(errored_test)
     @reporter.report
 
-    expect = %r{\AE\n\nError:\nTestUnitReporterTest::ExampleTest#woot:\nArgumentError: wups\n    No backtrace\n\nbin/rails test .*test/test_unit/reporter_test.rb:\d+\n\n\z}
+    expect = %r{\AE\n\nError:\nTestUnitReporterTest::ExampleTest#woot:\nArgumentError: wups\n    \n\nbin/rails test .*test/test_unit/reporter_test\.rb:\d+\n\n\z}
     assert_match expect, @output.string
   end
 
@@ -79,7 +81,7 @@ class TestUnitReporterTest < ActiveSupport::TestCase
     verbose.record(skipped_test)
     verbose.report
 
-    expect = %r{\ATestUnitReporterTest::ExampleTest#woot = 10\.00 s = S\n\n\nSkipped:\nTestUnitReporterTest::ExampleTest#woot \[[^\]]+\]:\nskipchurches, misstemples\n\nbin/rails test test/test_unit/reporter_test.rb:\d+\n\n\z}
+    expect = %r{\ATestUnitReporterTest::ExampleTest#woot = 10\.00 s = S\n\n\nSkipped:\nTestUnitReporterTest::ExampleTest#woot \[[^\]]+\]:\nskipchurches, misstemples\n\nbin/rails test test/test_unit/reporter_test\.rb:\d+\n\n\z}
     assert_match expect, @output.string
   end
 
@@ -87,7 +89,7 @@ class TestUnitReporterTest < ActiveSupport::TestCase
     @reporter.record(failed_test)
     @reporter.report
 
-    assert_no_match 'Failed tests:', @output.string
+    assert_no_match "Failed tests:", @output.string
   end
 
   test "fail fast interrupts run on failure" do
@@ -100,7 +102,7 @@ class TestUnitReporterTest < ActiveSupport::TestCase
     rescue Interrupt
       interrupt_raised = true
     ensure
-      assert interrupt_raised, 'Expected Interrupt to be raised.'
+      assert interrupt_raised, "Expected Interrupt to be raised."
     end
   end
 
@@ -114,7 +116,7 @@ class TestUnitReporterTest < ActiveSupport::TestCase
     rescue Interrupt
       interrupt_raised = true
     ensure
-      assert interrupt_raised, 'Expected Interrupt to be raised.'
+      assert interrupt_raised, "Expected Interrupt to be raised."
     end
   end
 
@@ -122,7 +124,7 @@ class TestUnitReporterTest < ActiveSupport::TestCase
     fail_fast = Rails::TestUnitReporter.new @output, fail_fast: true
 
     fail_fast.record(skipped_test)
-    assert_no_match 'Failed tests:', @output.string
+    assert_no_match "Failed tests:", @output.string
   end
 
   test "outputs colored passing results" do
@@ -150,44 +152,47 @@ class TestUnitReporterTest < ActiveSupport::TestCase
       colored = Rails::TestUnitReporter.new @output, color: true, output_inline: true
       colored.record(errored_test)
 
-      expected = %r{\e\[31mE\e\[0m\n\n\e\[31mError:\nTestUnitReporterTest::ExampleTest#woot:\nArgumentError: wups\n    No backtrace\n\e\[0m}
+      expected = %r{\e\[31mE\e\[0m\n\n\e\[31mError:\nTestUnitReporterTest::ExampleTest#woot:\nArgumentError: wups\n    \n\e\[0m}
       assert_match expected, @output.string
     end
   end
 
   private
-  def assert_rerun_snippet_count(snippet_count)
-    assert_equal snippet_count, @output.string.scan(%r{^bin/rails test }).size
-  end
+    def assert_rerun_snippet_count(snippet_count)
+      assert_equal snippet_count, @output.string.scan(%r{^bin/rails test }).size
+    end
 
-  def failed_test
-    ft = ExampleTest.new(:woot)
-    ft.failures << begin
-                     raise Minitest::Assertion, "boo"
-                   rescue Minitest::Assertion => e
-                     e
-                   end
-    ft
-  end
+    def failed_test
+      ft = ExampleTest.new(:woot)
+      ft.failures << begin
+                       raise Minitest::Assertion, "boo"
+                     rescue Minitest::Assertion => e
+                       e
+                     end
+      ft
+    end
 
-  def errored_test
-    et = ExampleTest.new(:woot)
-    et.failures << Minitest::UnexpectedError.new(ArgumentError.new("wups"))
-    et
-  end
+    def errored_test
+      error = ArgumentError.new("wups")
+      error.set_backtrace([ "some_test.rb:4" ])
 
-  def passing_test
-    ExampleTest.new(:woot)
-  end
+      et = ExampleTest.new(:woot)
+      et.failures << Minitest::UnexpectedError.new(error)
+      et
+    end
 
-  def skipped_test
-    st = ExampleTest.new(:woot)
-    st.failures << begin
-                     raise Minitest::Skip, "skipchurches, misstemples"
-                   rescue Minitest::Assertion => e
-                     e
-                   end
-    st.time = 10
-    st
-  end
+    def passing_test
+      ExampleTest.new(:woot)
+    end
+
+    def skipped_test
+      st = ExampleTest.new(:woot)
+      st.failures << begin
+                       raise Minitest::Skip, "skipchurches, misstemples"
+                     rescue Minitest::Assertion => e
+                       e
+                     end
+      st.time = 10
+      st
+    end
 end
diff --git a/railties/test/version_test.rb b/railties/test/version_test.rb
index f270d8f0c9..17a024fe7f 100644
--- a/railties/test/version_test.rb
+++ b/railties/test/version_test.rb
@@ -1,4 +1,6 @@
-require 'abstract_unit'
+# frozen_string_literal: true
+
+require "abstract_unit"
 
 class VersionTest < ActiveSupport::TestCase
   def test_rails_version_returns_a_string
diff --git a/tasks/release.rb b/tasks/release.rb
index 4a1ed04478..6ff06f3c4a 100644
--- a/tasks/release.rb
+++ b/tasks/release.rb
@@ -1,12 +1,27 @@
-FRAMEWORKS = %w( activesupport activemodel activerecord actionview actionpack activejob actionmailer actioncable railties )
+# frozen_string_literal: true
 
-root    = File.expand_path('../../', __FILE__)
+FRAMEWORKS = %w( activesupport activemodel activerecord actionview actionpack activejob actionmailer actioncable activestorage railties )
+FRAMEWORK_NAMES = Hash.new { |h, k| k.split(/(?<=active|action)/).map(&:capitalize).join(" ") }
+
+root    = File.expand_path("..", __dir__)
 version = File.read("#{root}/RAILS_VERSION").strip
 tag     = "v#{version}"
 
 directory "pkg"
 
-(FRAMEWORKS + ['rails']).each do |framework|
+# This "npm-ifies" the current version number
+# With npm, versions such as "5.0.0.rc1" or "5.0.0.beta1.1" are not compliant with its
+# versioning system, so they must be transformed to "5.0.0-rc1" and "5.0.0-beta1-1" respectively.
+
+# "5.0.1"     --> "5.0.1"
+# "5.0.1.1"   --> "5.0.1-1" *
+# "5.0.0.rc1" --> "5.0.0-rc1"
+#
+# * This makes it a prerelease. That's bad, but we haven't come up with
+# a better solution at the moment.
+npm_version = version.gsub(/\./).with_index { |s, i| i >= 2 ? "-" : s }
+
+(FRAMEWORKS + ["rails"]).each do |framework|
   namespace framework do
     gem     = "pkg/#{framework}-#{version}.gem"
     gemspec = "#{framework}.gemspec"
@@ -27,7 +42,7 @@ directory "pkg"
       file = Dir[glob].first
       ruby = File.read(file)
 
-      major, minor, tiny, pre = version.split('.', 4)
+      major, minor, tiny, pre = version.split(".", 4)
       pre = pre ? pre.inspect : "nil"
 
       ruby.gsub!(/^(\s*)MAJOR(\s*)= .*?$/, "\\1MAJOR = #{major}")
@@ -42,34 +57,15 @@ directory "pkg"
       ruby.gsub!(/^(\s*)PRE(\s*)= .*?$/, "\\1PRE   = #{pre}")
       raise "Could not insert PRE in #{file}" unless $1
 
-      File.open(file, 'w') { |f| f.write ruby }
+      File.open(file, "w") { |f| f.write ruby }
 
-      if File.exist?("#{framework}/package.json")
+      require "json"
+      if File.exist?("#{framework}/package.json") && JSON.parse(File.read("#{framework}/package.json"))["version"] != npm_version
         Dir.chdir("#{framework}") do
-          # This "npm-ifies" the current version
-          # With npm, versions such as "5.0.0.rc1" or "5.0.0.beta1.1" are not compliant with its
-          # versioning system, so they must be transformed to "5.0.0-rc1" and "5.0.0-beta1-1" respectively.
-
-          # In essence, the code below runs through all "."s that appear in the version,
-          # and checks to see if their index in the version string is greater than or equal to 2,
-          # and if so, it will change the "." to a "-".
-
-          # Sample version transformations:
-          # irb(main):001:0> version = "5.0.1.1"
-          # => "5.0.1.1"
-          # irb(main):002:0> version.gsub(/\./).with_index { |s, i| i >= 2 ? '-' : s }
-          # => "5.0.1-1"
-          # irb(main):003:0> version = "5.0.0.rc1"
-          # => "5.0.0.rc1"
-          # irb(main):004:0> version.gsub(/\./).with_index { |s, i| i >= 2 ? '-' : s }
-          # => "5.0.0-rc1"
-          version = version.gsub(/\./).with_index { |s, i| i >= 2 ? '-' : s }
-
-          # Check if npm is installed, and raise an error if not
-          if sh 'which npm'
-            sh "npm version #{version} --no-git-tag-version"
+          if sh "which npm"
+            sh "npm version #{npm_version} --no-git-tag-version"
           else
-            raise 'You must have npm installed to release Rails.'
+            raise "You must have npm installed to release Rails."
           end
         end
       end
@@ -77,51 +73,59 @@ directory "pkg"
 
     task gem => %w(update_versions pkg) do
       cmd = ""
-      cmd << "cd #{framework} && " unless framework == "rails"
-      cmd << "bundle exec rake package && " unless framework == "rails"
-      cmd << "gem build #{gemspec} && mv #{framework}-#{version}.gem #{root}/pkg/"
+      cmd += "cd #{framework} && " unless framework == "rails"
+      cmd += "bundle exec rake package && " unless framework == "rails"
+      cmd += "gem build #{gemspec} && mv #{framework}-#{version}.gem #{root}/pkg/"
       sh cmd
     end
 
-    task :build => [:clean, gem]
-    task :install => :build do
+    task build: [:clean, gem]
+    task install: :build do
       sh "gem install --pre #{gem}"
     end
 
-    task :push => :build do
+    task push: :build do
       sh "gem push #{gem}"
-      sh "npm publish" if File.exist?("#{framework}/package.json")
+
+      if File.exist?("#{framework}/package.json")
+        Dir.chdir("#{framework}") do
+          npm_tag = version =~ /[a-z]/ ? "pre" : "latest"
+          sh "npm publish --tag #{npm_tag}"
+        end
+      end
     end
   end
 end
 
 namespace :changelog do
   task :header do
-    (FRAMEWORKS + ['guides']).each do |fw|
-      require 'date'
-      fname = File.join fw, 'CHANGELOG.md'
-
-      header = "## Rails #{version} (#{Date.today.strftime('%B %d, %Y')}) ##\n\n*   No changes.\n\n\n"
-      contents = header + File.read(fname)
-      File.open(fname, 'wb') { |f| f.write contents }
+    (FRAMEWORKS + ["guides"]).each do |fw|
+      require "date"
+      fname = File.join fw, "CHANGELOG.md"
+      current_contents = File.read(fname)
+
+      header = "## Rails #{version} (#{Date.today.strftime('%B %d, %Y')}) ##\n\n"
+      header += "*   No changes.\n\n\n" if current_contents =~ /\A##/
+      contents = header + current_contents
+      File.open(fname, "wb") { |f| f.write contents }
     end
   end
 
   task :release_date do
-    (FRAMEWORKS + ['guides']).each do |fw|
-      require 'date'
+    (FRAMEWORKS + ["guides"]).each do |fw|
+      require "date"
       replace = "## Rails #{version} (#{Date.today.strftime('%B %d, %Y')}) ##\n"
-      fname = File.join fw, 'CHANGELOG.md'
+      fname = File.join fw, "CHANGELOG.md"
 
       contents = File.read(fname).sub(/^(## Rails .*)\n/, replace)
-      File.open(fname, 'wb') { |f| f.write contents }
+      File.open(fname, "wb") { |f| f.write contents }
     end
   end
 
   task :release_summary do
-    (FRAMEWORKS + ['guides']).each do |fw|
+    (FRAMEWORKS + ["guides"]).each do |fw|
       puts "## #{fw}"
-      fname    = File.join fw, 'CHANGELOG.md'
+      fname    = File.join fw, "CHANGELOG.md"
       contents = File.readlines fname
       contents.shift
       changes = []
@@ -133,35 +137,63 @@ namespace :changelog do
 end
 
 namespace :all do
-  task :build           => FRAMEWORKS.map { |f| "#{f}:build"           } + ['rails:build']
-  task :update_versions => FRAMEWORKS.map { |f| "#{f}:update_versions" } + ['rails:update_versions']
-  task :install         => FRAMEWORKS.map { |f| "#{f}:install"         } + ['rails:install']
-  task :push            => FRAMEWORKS.map { |f| "#{f}:push"            } + ['rails:push']
+  task build: FRAMEWORKS.map { |f| "#{f}:build"           } + ["rails:build"]
+  task update_versions: FRAMEWORKS.map { |f| "#{f}:update_versions" } + ["rails:update_versions"]
+  task install: FRAMEWORKS.map { |f| "#{f}:install"         } + ["rails:install"]
+  task push: FRAMEWORKS.map { |f| "#{f}:push"            } + ["rails:push"]
 
   task :ensure_clean_state do
-    unless `git status -s | grep -v 'RAILS_VERSION\\|CHANGELOG\\|Gemfile.lock'`.strip.empty?
+    unless `git status -s | grep -v 'RAILS_VERSION\\|CHANGELOG\\|Gemfile.lock\\|package.json\\|version.rb\\|tasks/release.rb'`.strip.empty?
       abort "[ABORTING] `git status` reports a dirty tree. Make sure all changes are committed"
     end
 
-    unless ENV['SKIP_TAG'] || `git tag | grep '^#{tag}$'`.strip.empty?
+    unless ENV["SKIP_TAG"] || `git tag | grep '^#{tag}$'`.strip.empty?
       abort "[ABORTING] `git tag` shows that #{tag} already exists. Has this version already\n"\
             "           been released? Git tagging can be skipped by setting SKIP_TAG=1"
     end
   end
 
+  task verify: :install do
+    app_name = "pkg/verify-#{version}-#{Time.now.to_i}"
+    sh "rails _#{version}_ new #{app_name} --skip-bundle" # Generate with the right version.
+    cd app_name
+
+    # Replace the generated gemfile entry with the exact version.
+    File.write("Gemfile", File.read("Gemfile").sub(/^gem 'rails.*/, "gem 'rails', '#{version}'"))
+    sh "bundle"
+
+    sh "rails generate scaffold user name admin:boolean && rails db:migrate"
+
+    puts "Booting a Rails server. Verify the release by:"
+    puts
+    puts "- Seeing the correct release number on the root page"
+    puts "- Viewing /users"
+    puts "- Creating a user"
+    puts "- Updating a user (e.g. disable the admin flag)"
+    puts "- Deleting a user on /users"
+    puts "- Whatever else you want."
+    begin
+      sh "rails server"
+    rescue Interrupt
+      # Server passes along interrupt. Prevent halting verify task.
+    end
+  end
+
   task :bundle do
-    sh 'bundle check'
+    sh "bundle check"
   end
 
   task :commit do
-    File.open('pkg/commit_message.txt', 'w') do |f|
-      f.puts "# Preparing for #{version} release\n"
-      f.puts
-      f.puts "# UNCOMMENT THE LINE ABOVE TO APPROVE THIS COMMIT"
-    end
+    unless `git status -s`.strip.empty?
+      File.open("pkg/commit_message.txt", "w") do |f|
+        f.puts "# Preparing for #{version} release\n"
+        f.puts
+        f.puts "# UNCOMMENT THE LINE ABOVE TO APPROVE THIS COMMIT"
+      end
 
-    sh "git add . && git commit --verbose --template=pkg/commit_message.txt"
-    rm_f "pkg/commit_message.txt"
+      sh "git add . && git commit --verbose --template=pkg/commit_message.txt"
+      rm_f "pkg/commit_message.txt"
+    end
   end
 
   task :tag do
@@ -169,7 +201,52 @@ namespace :all do
     sh "git push --tags"
   end
 
-  task :prep_release => %w(ensure_clean_state build)
+  task prep_release: %w(ensure_clean_state build bundle commit)
+
+  task release: %w(prep_release tag push)
+end
+
+module Announcement
+  class Version
+    def initialize(version)
+      @version, @gem_version = version, Gem::Version.new(version)
+    end
+
+    def to_s
+      @version
+    end
+
+    def previous
+      @gem_version.segments[0, 3].tap { |v| v[2] -= 1 }.join(".")
+    end
+
+    def major_or_security?
+      @gem_version.segments[2].zero? || @gem_version.segments[3].is_a?(Integer)
+    end
+
+    def rc?
+      @version =~ /rc/
+    end
+  end
+end
+
+task :announce do
+  Dir.chdir("pkg/") do
+    versions = ENV["VERSIONS"] ? ENV["VERSIONS"].split(",") : [ version ]
+    versions = versions.sort.map { |v| Announcement::Version.new(v) }
+
+    raise "Only valid for patch releases" if versions.any?(&:major_or_security?)
 
-  task :release => %w(ensure_clean_state build bundle commit tag push)
+    if versions.any?(&:rc?)
+      require "date"
+      future_date = Date.today + 5
+      future_date += 1 while future_date.saturday? || future_date.sunday?
+
+      github_user = `git config github.user`.chomp
+    end
+
+    require "erb"
+    template = File.read("../tasks/release_announcement_draft.erb")
+    puts ERB.new(template, nil, "<>").result(binding)
+  end
 end
diff --git a/tasks/release_announcement_draft.erb b/tasks/release_announcement_draft.erb
new file mode 100644
index 0000000000..3dbb8c053f
--- /dev/null
+++ b/tasks/release_announcement_draft.erb
@@ -0,0 +1,38 @@
+Hi everyone,
+
+I am happy to announce that Rails <%= versions.join(" and ") %> <%= versions.size > 1 ? "have" : "has" %> been released.
+
+<% if future_date %>
+If no regressions are found, expect the final release on <%= future_date.strftime("%A, %B %-d, %Y") %>.
+If you find one, please open an [issue on GitHub](https://github.com/rails/rails/issues/new)
+<%= "and mention me (@#{github_user}) on it, " unless github_user.empty? %>so that we can fix it before the final release.
+<% end %>
+<% versions.each do |version| %>
+
+## CHANGES since <%= version.previous %>
+
+To view the changes for each gem, please read the changelogs on GitHub:
+  <% FRAMEWORKS.sort.each do |framework| %>
+<%= "* [#{FRAMEWORK_NAMES[framework]} CHANGELOG](https://github.com/rails/rails/blob/v#{version}/#{framework}/CHANGELOG.md)" %>
+  <% end %>
+
+*Full listing*
+
+To see the full list of changes, [check out all the commits on
+GitHub](https://github.com/rails/rails/compare/v<%= "#{version.previous}...v#{version}" %>).
+  <% end %>
+## SHA-256
+
+If you'd like to verify that your gem is the same as the one I've uploaded,
+please use these SHA-256 hashes.
+
+<% versions.each do |version| %>
+Here are the checksums for <%= version %>:
+
+```
+$ shasum -a 256 *-<%= version %>.gem
+<%= `shasum -a 256 *-#{version}.gem` %>
+```
+
+<% end %>
+As always, huge thanks to the many contributors who helped with this release.
diff --git a/tools/README.md b/tools/README.md
index b2e7e4b0ae..f133b27128 100644
--- a/tools/README.md
+++ b/tools/README.md
@@ -6,3 +6,5 @@ They aren't used by Rails apps directly.
   * `console` drops you in irb and loads local Rails repos
   * `profile` profiles `Kernel#require` to help reduce startup time
   * `line_statistics` provides CodeTools module and LineStatistics class to count lines
+  * `test` is loaded by every major component of Rails to simplify testing, for example:
+    `cd ./actioncable; bin/test ./path/to/actioncable_test_with_line_number.rb:5`
diff --git a/tools/console b/tools/console
index 98a848ff6b..ee08e22502 100755
--- a/tools/console
+++ b/tools/console
@@ -1,9 +1,11 @@
 #!/usr/bin/env ruby
-require 'bundler'
+# frozen_string_literal: true
+
+require "bundler"
 Bundler.setup
 
-require 'rails/all'
-require 'active_support/all'
-require 'irb'
-require 'irb/completion'
+require "rails/all"
+require "active_support/all"
+require "irb"
+require "irb/completion"
 IRB.start
diff --git a/tools/profile b/tools/profile
index 191e73b3dd..6fb571f43b 100755
--- a/tools/profile
+++ b/tools/profile
@@ -1,21 +1,23 @@
 #!/usr/bin/env ruby
+# frozen_string_literal: true
+
 # Profile require calls giving information about the time and the files that are called
 # when loading the provided file.
 #
 # Example:
 #   tools/profile activesupport/lib/active_support.rb [ruby-prof mode] [ruby-prof printer]
-ENV['NO_RELOAD'] ||= '1'
-ENV['RAILS_ENV'] ||= 'development'
+ENV["NO_RELOAD"] ||= "1"
+ENV["RAILS_ENV"] ||= "development"
 
 module CodeTools
   class Profiler
     Error = Class.new(StandardError)
 
     attr_reader :path, :mode
-    def initialize(path, mode=nil)
+    def initialize(path, mode = nil)
       assert_ruby_file_exists(path)
       @path, @mode = path, mode
-      require 'benchmark'
+      require "benchmark"
     end
 
     def profile_requires
@@ -23,7 +25,7 @@ module CodeTools
       before_rss = `ps -o rss= -p #{Process.pid}`.to_i
 
       if mode
-        require 'ruby-prof'
+        require "ruby-prof"
         RubyProf.measure_mode = RubyProf.const_get(mode.upcase)
         RubyProf.start
       else
@@ -43,13 +45,13 @@ module CodeTools
         elsif RubyProf.const_defined?(:CallStackPrinter)
           filename = "#{File.basename(path, '.rb')}.#{mode}.html"
           puts "RubyProf outputting to #{filename}"
-          File.open(filename, 'w') do |out|
+          File.open(filename, "w") do |out|
             RubyProf::CallStackPrinter.new(results).print(out)
           end
         else
           filename = "#{File.basename(path, '.rb')}.#{mode}.callgrind"
           puts "RubyProf outputting to #{filename}"
-          File.open(filename, 'w') do |out|
+          File.open(filename, "w") do |out|
             RubyProf::CallTreePrinter.new(results).print(out)
           end
         end
@@ -57,7 +59,7 @@ module CodeTools
 
       RequireProfiler.stats.each do |file, depth, sec|
         if sec
-          puts "%8.1f ms  %s%s" % [sec * 1000, ' ' * depth, file]
+          puts "%8.1f ms  %s%s" % [sec * 1000, " " * depth, file]
         else
           puts "#{' ' * (13 + depth)}#{file}"
         end
@@ -67,51 +69,51 @@ module CodeTools
 
     private
 
-    def assert_ruby_file_exists(path)
-      fail Error.new("No such file") unless File.exist?(path)
-      fail Error.new("#{path} is a directory") if File.directory?(path)
-      ruby_extension = File.extname(path) == '.rb'
-      ruby_executable = File.open(path, 'rb') {|f| f.readline } =~ [/\A#!.*ruby/]
-      fail Error.new("Not a ruby file") unless ruby_extension or ruby_executable
-    end
+      def assert_ruby_file_exists(path)
+        fail Error.new("No such file") unless File.exist?(path)
+        fail Error.new("#{path} is a directory") if File.directory?(path)
+        ruby_extension = File.extname(path) == ".rb"
+        ruby_executable = File.open(path, "rb") { |f| f.readline } =~ [/\A#!.*ruby/]
+        fail Error.new("Not a ruby file") unless ruby_extension || ruby_executable
+      end
 
-    module RequireProfiler
-      private
-      def require(file, *args) RequireProfiler.profile(file) { super } end
-      def load(file, *args) RequireProfiler.profile(file) { super } end
+      module RequireProfiler
+        private
+          def require(file, *args) RequireProfiler.profile(file) { super } end
+          def load(file, *args) RequireProfiler.profile(file) { super } end
 
-      @depth, @stats = 0, []
-      class << self
-        attr_accessor :depth
-        attr_accessor :stats
+          @depth, @stats = 0, []
+          class << self
+            attr_accessor :depth
+            attr_accessor :stats
 
-        def profile(file)
-          stats << [file, depth]
-          self.depth += 1
-          result = nil
-          elapsed = Benchmark.realtime { result = yield }
-          self.depth -= 1
-          stats.pop if stats.last.first == file
-          stats << [file, depth, elapsed] if result
-          result
-        end
+            def profile(file)
+              stats << [file, depth]
+              self.depth += 1
+              result = nil
+              elapsed = Benchmark.realtime { result = yield }
+              self.depth -= 1
+              stats.pop if stats.last.first == file
+              stats << [file, depth, elapsed] if result
+              result
+            end
+          end
       end
-    end
   end
 end
 # ruby-prof printer name causes the third arg to be sent :classify
 #   which is probably overkill if you already know the name of the ruby-prof
 #   printer you want to use, e.g. Graph
 begin
-  require 'active_support/inflector'
-  require 'active_support/core_ext/string/inflections'
+  require "active_support/inflector"
+  require "active_support/core_ext/string/inflections"
 rescue LoadError
   STDERR.puts $!.message
   class String
     # File activesupport/lib/active_support/inflector/methods.rb, line 150
     def classify
       # strip out any leading schema name
-      camelize(self.sub(/.*\./, ''))
+      camelize(sub(/.*\./, ""))
     end
     # File activesupport/lib/active_support/inflector/methods.rb, line 68
     def camelize(uppercase_first_letter = true)
@@ -121,7 +123,7 @@ rescue LoadError
       else
         string = string.sub(/^(?:(?=\b|[A-Z_])|\w)/) { |match| match.downcase }
       end
-      string.gsub(/(?:_|(\/))([a-z\d]*)/) { "#{$1}#{$2.capitalize}" }.gsub('/', '::')
+      string.gsub(/(?:_|(\/))([a-z\d]*)/) { "#{$1}#{$2.capitalize}" }.gsub("/", "::")
     end
   end
 end
diff --git a/tools/test.rb b/tools/test.rb
index 62e0faa3db..1fd3ee30eb 100644
--- a/tools/test.rb
+++ b/tools/test.rb
@@ -1,15 +1,26 @@
+# frozen_string_literal: true
+
 $: << File.expand_path("test", COMPONENT_ROOT)
 
-require 'bundler'
+require "bundler"
 Bundler.setup
 
-require "rails/test_unit/minitest_plugin"
+require "rails/test_unit/runner"
+require "rails/test_unit/reporter"
+require "rails/test_unit/line_filtering"
+require "active_support"
+require "active_support/test_case"
 
-module Rails
-  # Necessary to get rerun-snippts working.
-  def self.root
+class << Rails
+  # Necessary to get rerun-snippets working.
+  def root
     @root ||= Pathname.new(COMPONENT_ROOT)
   end
+  alias __root root
 end
 
+ActiveSupport::TestCase.extend Rails::LineFiltering
 Rails::TestUnitReporter.executable = "bin/test"
+
+Rails::TestUnit::Runner.parse_options(ARGV)
+Rails::TestUnit::Runner.run(ARGV)
diff --git a/version.rb b/version.rb
index 9c49e0655a..2cc861a1bd 100644
--- a/version.rb
+++ b/version.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module Rails
   # Returns the version of the currently loaded Rails as a <tt>Gem::Version</tt>
   def self.gem_version
@@ -6,9 +8,9 @@ module Rails
 
   module VERSION
     MAJOR = 5
-    MINOR = 1
+    MINOR = 2
     TINY  = 0
-    PRE   = "alpha"
+    PRE   = "beta2"
 
     STRING = [MAJOR, MINOR, TINY, PRE].compact.join(".")
   end